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Effect of Radiofrequency Radiation from Telecommunication Base Stations on Microbial Diversity and Antibiotic Resistance

DOI:10.4314/jasem.v18i4.16
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Eliajh Adebayo at Ladoke Akintola University of Technology
Eliajh Adebayo
Adeyemi Ojutalayo Adeeyo at University of Venda
Adeyemi Ojutalayo Adeeyo
Abiodun Ayanfemi Ayandele at Ladoke Akintola University of Technology
Abiodun Ayanfemi Ayandele
Ola Iyabo at Ladoke Akintola University of Technology
Ola Iyabo
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We aimed to investigate the effects of radiofrequency radiation from telecommunication on bacteria diversity and antibiotic sensitivity of surrounding bacteria micro-flora. In all cases of bacteria isolated, results indicated that radiation majorly influen ces and selected bacteria of specific morphology (rod-like, gram positive and spore formers) belonging to the genera Bacillus, Clostridium, Corynebacterium and Sporosarcina. Spore formation have been associated with prevention of DNA damage, this suggest t hat radiation may imposes stress detrimental to various non-spore forming, gram negative bacteria of nonrod morphology. The antibiotic resistance pattern indicated resistance above 50% in three of the ten common antibiotics tested with the highest of 96% recorded against zinnacef, followed by amoxicillin (70%) and ampiclox (56%). The highest resistance recorded was attributed to Bacillus spp while lowest resistance was recorded in Corynebacterium. The two largest groups of isolates; Bacillus and Clostridium have been reported as human pathogens and found to be multidrug resistant.
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JASEM ISSN 1119-8362
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J A S E M .
OURNAL OF PPLIED CIENCE AND NVIRONMENTAL ANAGEMENT
J. Appl. Sci. Environ. Manage. December, 2014
Vol. 18 (4) 669 - 674
Full-text Available Online at
www.ajol.info and
www.bioline.org.br/ja
Effect of Radiofrequency Radiation from Telecommunication Base Stations on
Microbial Diversity and Antibiotic Resistance
E.A, ADEBAYO1; A.O, ADEEYO*1; A.A, AYANDELE1 I.O, OMOMOWO1
1 Department of Pure and Applied Biology, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Nigeria
eaadebayo@lautech.edu.ng; firstrebby@gmail.com, lizdeley@yahoo.com and olaiyabo@yahoo.com
*Corresponding author: A.O ADEEYO. E-Mail: firstrebby@gmail.com
ABSTRACT: We aimed to investigate the effects of radiofrequency radiation from
telecommunication on bacteria diversity and antibiotic sensitivity of surrounding bacteria
micro-flora. In all cases of bacteria isolated, results indicated that radiation majorly influences
and selected bacteria of specific morphology (rod-like, gram positive and spore formers)
belonging to the genera Bacillus, Clostridium, Corynebacterium and Sporosarcina. Spore
formation have been associated with prevention of DNA damage, this suggest that radiation
may imposes stress detrimental to various non-spore forming, gram negative bacteria of non-
rod morphology. The antibiotic resistance pattern indicated resistance above 50% in three of
the ten common antibiotics tested with the highest of 96% recorded against zinnacef, followed
by amoxicillin (70%) and ampiclox (56%). The highest resistance recorded was attributed to
Bacillus spp while lowest resistance was recorded in Corynebacterium. The two largest
groups of isolates; Bacillus and Clostridium have been reported as human pathogens and
found to be multidrug resistant. © JASEM
http://dx.doi.org/10.4314/jasem.v18i4.16
Introduction:
Before the 1990’s radiofrequencies were mainly from
a few radio and television transmitters, located in
remote areas and/or very high places. Since the
introduction of wireless telecommunication in the
1990’s the rollout of phone networks has caused a
massive increase in electromagnetic pollution in
cities and the countryside (Firstenberg, 1997; Galeev,
2000). Multiple sources of mobile communication
result in chronic exposure of a significant part of life
(and man) to microwaves at non-thermal levels
(Belyaev, 2005). In recent years, life has been
chronically exposed to microwaves and RFR
(Radiofrequency radiation) signals from various
sources, including Global system for mobile
communication (GSM) and UMTS/3G wireless
phones and base stations, Wireless Local Area
Networks (WLAN), Wireless Personal Area
Networks such as Bluetooth (WPAN), and DECT
(Digital Enhanced (former European) Cordless
Telecommunications) that are erected
indiscriminately without studies of environmental
impact assessments.
The effects of RFR on the biological functions of
living organisms represent an emerging area of
interest with respect to environmental influences on
human health. In latest years, several studies have
been performed to verify direct effects exerted by
such radiations on cell functions. Although results
have been somewhat controversial, a variety of cell
responses have been observed involving proliferation
and differentiation (Huang et al., 2006; Lisi et al.,
2006; Lisi et al., 2008; Vianale et al., 2008; Schwartz
et al., 2008; Foleti et al., 2009), gene expression
(Piacentini et al., 2008; Goodman et al., 2009),
modulation of the membrane receptors functionality
(Jia et al., 2007; Ke at al., 2008; De-Mattei et al.,
2009), apoptosis, alteration in ion homeostasis
(Grassi et al., 2004; Lisi et al., 2006; Iorio et al.,
2011 ), and free radicals generation (Simk, 2007; Di-
Loreto et al., 2009). Bacteria have also been used in
the studies with radiofrequency radiation (Straˇs´ak,
et al., 2005; Fojt et al., 2004; Babushkina et al.,
2005; Justo et al., 2006; Gaafar et al., 2006; Cellini et
al., 2008; Gaafar et al., 2008; Fojt., 2009; Belyaev,
2011; Inhan-Garip et al., 2011, Giorgi et al., 2011).
In particular, it has been demonstrated that radiation
can negatively (Straˇs´ak, et al., 2005; Fojt et al.,
2004; Justo et al., 2006) or positively (Gaafar et al.,
2006; Cellini et al., 2008; Belyaev, 2011) affect
functional parameters (cell growth and viability) and
bacteria antibiotic sensitivity depending on physical
parameters of the electromagnetic field (frequency
and magnetic flux density) applied, the time of the
exposure, and/or the type of bacteria cells used. The
possibility of an effect evoked by RFR on bacterial
distribution and antibiotic resistance deserves special
Effect of Radiofrequency Radiation from Telecommunication Base Stations on Microbial Diversity and Antibiotic Resistance 670
E.A, ADEBAYO1; A.O, ADEEYO*1; A.A, AYANDELE1; I.O, OMOMOWO1
attention in light of the risk that antimicrobial
resistance poses to public health. Bacteria are
becoming increasingly resistant to almost all
presently available antibiotics and this aspect is
becoming a worldwide problem of highest
significance (Levi, 2001; Bush et al., 2011).
According to these considerations, the study of
effects of RFR on bacteria is essential not only for
investigation of environmental stress influences on
biological systems, but also to explore the antibiotic
resistance pattern associated for possibility of
controlling bacteria in the environment or in clinical
laboratories. We have therefore attempted to
investigate the possible influence of RFR on bacteria
distribution and antibiotic resistance on surrounding
bacteria micro-flora of telecommunication base
stations located around Ladoke Akintola University
of Technology, Ogbomoso, Oyo State, Nigeria.
MATERIALS AND METHODS
Sample collection: Soil samples were collected from
telecommunication base station located around
Ladoke Akintola University of Technology,
Ogbomoso, Oyo State, Nigeria. These were collected
between 0 and 100ft (0, 10, 40, 70 and 100ft) from
the foot of 3 base stations. Soil samples were
aseptically transferred to the laboratory for microbial
analysis.
Isolation of organisms: 1 g of each soil samples was
weighed into 10 ml of sterile distilled water.
Subsequent transfer of 1 ml into 9 ml of sterile
distilled water was engaged for serial dilution of the
prepared samples followed by plating out on nutrient
agar using pour plate techniques. The cultures were
incubated at 37oC for 24 h from where pure cultures
were prepared based on bacteria morphology using
the streaking out method.
Biochemical characterization and identification of
pure cultures: Pure bacterial cultures were identified
on the basis of grams reaction, morphology and
biochemical reactions including sugar hydrolysis,
catalase, oxidase, urease, indole, citrate utilization,
methyl red, nitrate reduction and voges proskaeur
tests. The organisms isolated were then characterized
according to the taxonomic scheme of Buchanan and
Gibbons (1974).
Antibiotic susceptibility tests: Susceptibility of
purified bacterial cultures to a set of ten antimicrobial
substances was assessed by disk diffusion on
Mueller-Hinton agar plates according to the Clinical
and Laboratory Standards Institute guidelines (CLSI,
2007). After incubation, for 24 h at 37oC, the sizes of
zones of inhibitions were measured and interpreted
by comparing with the standard antibiotic sensitivity
chart to determine their resistant patterns. Resistance
was calculated according to the method of Adebayo
et al. (2012).
Antimicrobial agents: Antibiotics used include
Pefloxacin (PEF), Gentamycin (CN), Ampiclox
(APX), Zinnacef (Z), Amoxicillin (AM), Rocephin
(R), Ciprofloxacin (CPX), Streptomycin (S), Septrin
(SXT), and Erythromycin (E) and were purchased
through Labtrade Chemicals, Nigeria.
RESULTS AND DISCUSSION:
The result of microbial diversity and prevalence
around telecommunication base stations studied is
indicated in Table 1. A total of 27 bacteria isolates
belonging to four genera were identified. Result show
a high occurrence of Bacillus spp (78 %), followed
by Clostridium spp (11 %), Corynebacterium
striatum (7 %) and Sporosarcina ureae (4 %) with
the lowest distribution. Result indicated that RFR
majorly influences and selected bacteria of specific
morphology (rod-like, gram positive and spore
formers) around the three telecommunication base
stations sampled. Radiation effect seems to favour
majorly the growth of Bacillus spp between the
distance of 0 and 100ft with occasional presence of
Corynebacterium striatum, Sporosarcina ureae and
Clostridium tertium at 10, and 70ft from the base
station. Spore formation has been associated with
prevention of DNA damage and this suggests that
radiation may impose stress detrimental to various
non-spore forming, gram negative bacteria of non-rod
shape. The presence of limited genera which are
mostly spore formers showed that these groups
survived because of their ability to form spores which
protected them from the negative effect of radiation
while others are probably eliminated. Rifat et al.
(2010) reported Rhizobium, Bradyrhizobium,
Azorhizobium, Allorhizobium, Sinorhizobium,
Mesorhizobium, Azospirillum, Enterobacter,
Klebsiella, and Pseudomonas spp as symbiotic and
free living beneficial groups of bacteria commonly
encountered in the soil and have potential to
contribute to sustainable plant growth. However none
of these were isolated. The depletion of such nitrogen
fixing bacteria will likely lead to soil infertility as
such organism cannot protect themselves from the
effect of radiation. This may invariably lead to
reduction in yield and productivity of food crops in
such environment. Previous report have implicated
the ability of radiation to induce changes of cell
growth and antibiotic sensitivity in bacteria strains
(Grossman et al., 1992; Stansell et al., 2001;
Effect of Radiofrequency Radiation from Telecommunication Base Stations on Microbial Diversity and Antibiotic Resistance 671
E.A, ADEBAYO1; A.O, ADEEYO*1; A.A, AYANDELE1; I.O, OMOMOWO1
Table 1: Diversity and prevalence of bacteria isolates from Telecommunication
base stations in LAUTECH.
Isolates
Gram reaction
Shape
Spore formation
Bacillus spp
Positive
Rods
Spore formers
Clostridium spp
Positive
Rods
Spore formers
Corynebacterium striatum
Positive
Rods
Non-Spore
formers
Sporosarcina ureae
Positive
cocci
Spore formers
Fojt et al., 2004; Justo et al., 2006; Fojt et al., 2007;
Fojt et al., 2009). It has been found that viability of
different types of bacteria (Escherichia coli,
Leclercia adecarboxylata, and Staphylococcus
aureus) was affected after exposure to an RFR (Fojt
et al., 2004). RFR have been reported to be lethal in
Paracoccus denitrificans, but without changes in
denitrification activity (Fojt et al., 2009). While RFR
as reported in this work is attributed to influencing
the presence of majorly rod-shaped bacteria, Fojt et
al. (2008) do not observe any change in bacterial
morphology after short period of exposure to RFR
suggesting that the radiation selected and caused
survival of bacteria with specific shape and adaptive
feature in the environment rather than causing a
shape change in such organism. On the contrary, it
has been demonstrated that short-term exposure RFR
with a sinusoidal waveform of amplitude ranging
from 0.1 to 1mT and frequency of 50 Hz affected
morphology of cultured E. coli ATCC 700926
(Cellini et al., 2008).
The antibiotic resistant patterns of various bacteria
isolated are indicated In Table 2 and Figure 1.
Antibiotic resistance among the radiofrequency
radiation resistant bacteria indicated that resistance
was above 50% in three of the ten common
antibiotics tested. Among the twenty seven isolates,
26 (96%) were resistant to zinnacef, 19 (70%) to
amoxicillin, 15 (56%) to ampiclox, 5 (19%) to
pefloxacin and gentamycin respectively, 3 (11%) to
erythromycin, 2 (7%) to rocephin and septrin and 1
(4%) to streptomycin and ciprofloxacin. With respect
to the ten antibiotics used, Bacillus spp has resistance
to all (100%) antibiotics used, Clostridium spp was
resistant to four (40 %) while Corynebacterium
striatum and Sporosarcina ureae were resistant to
two (20% resistant) each, among the ten antibiotic
used. Highest resistance was recorded in Bacillus spp
while lowest resistance was recorded in
Corynebacterium. The two largest groups of isolates
of Bacillus and Clostridium have been reported as
human pathogens and found to be multidrug resistant
(Conner-kerr et al., 1998). Bacillus circulans and
Clostridium septicum have been
Table 2: Antibiotic resistant pattern in radiofrequency radiation resistant bacteria Isolated from LAUTECH.
Isolates
Antibiotics with proportion and percentage bacteria resistance
Number
PEF
CN
APX
Z
AM
R
CPX
S
SXT
E
Bacillus spp
21
5
4
11
20
16
2
1
1
2
3
Clostridium spp
3
0
1
1
3
2
0
0
0
0
0
Corynebacterium
striatum
2
0
0
2
2
0
0
0
0
0
0
Sporosarcina ureae
1
0
0
1
1
1
0
0
0
0
0
Total
27
5(19%)
5(19%)
15(56%)
26(96%)
19(70%)
2(7%)
1(4%)
1(4%)
2(7%)
3(11%)
Pefloxacin (PEF), Gentamycin (CN), Ampiclox (APX), Zinnacef (Z), Amoxicillin (AM), Rocephin (R),
Ciprofloxacin (CPX), Streptomycin (S), Septrin (SXT), and Erythromycin (E)
Effect of Radiofrequency Radiation from Telecommunication Base Stations on Microbial Diversity and Antibiotic Resistance 672
E.A, ADEBAYO1; A.O, ADEEYO*1; A.A, AYANDELE1; I.O, OMOMOWO1
Fig 1: Percentage resistance to antibiotics among bacteria strains isolated
Pefloxacin (PEF), Gentamycin (CN), Ampiclox (APX), Zinnacef (Z), Amoxicillin (AM), Rocephin (R),
Ciprofloxacin (CPX), Streptomycin (S), Septrin (SXT), and Erythromycin (E)
associated with gas gangrene which is highly fatal
and may result into death in less than 24 h (Katlic,
1980). Clostridium septicum is highly pathogenic in
immune-compromised individuals, Corynebacterium
striatum have been implicated in endocarditis,
bacteremia and catheter infections (Coyle et al.,
1990). Bacillus cereus causes food poisoning,
diarrhea, severe nausea and vomiting (McKillip,
2000). Bacillus circulans is a pathogen incriminated
in human infection such as septicemia, mixed
abscesses and wound infection. Antibiotic resistance
increases in the environment as they replicate their
genetic materials; this means that resistance can
spread from one species of bacteria to the other
enabling it to develop multiple resistances to different
classes of antibiotics. Electromagnetic fields have
been reported in acquisition of resistance to
Cephalosporins (Cefuroxime and Ceftazidime) (Fojt
et al., 2007; Cellini et al., 2008). Justo et al. (2006)
reported that cell growth could be altered (stimulated
or inhibited) under magnetic field effects. Exposure
of bacteria to radiation have been reported to cause
changes in the growth characteristic, morphology,
structural properties of proteins, and the sensitivity
and resistance to certain antibiotics such as
amoxicillin, nalidixic acid, and erythromycin (Gaafar
et al., 2006; Gaafar et al., 2008). These results were
in agreement with the work of Stansell et al. (2001)
who found that moderate intensity static fields were
able affect antibiotic sensitivity and resistance of
bacteria. Furthermore, Belyaev (2011) showed that
RFR, under specific conditions of exposure
(frequency ranging from 8.5Hz to 9 Hz; 0.021mT),
acted as a nontoxic but cell-growth stimulating agent
on E. coli GE499. Again, the exposure of E. coli HB-
101 to radiation produced a stimulation of cell
growth (Babushkina et al., 2005). By contrast,
Grosman et al. (1992) found that static magnetic
fields ranging from 0.5 to 4.0 T had no significant
influence on the growth rate and antibiotic sensitivity
of E. coli and Staphylococcus aureus. A direct
comparison of these studies with results obtained in
this work may be difficult because of the dissimilar
experimental procedures employed. It is well known
that the effects of radiation generally depend on both
physical and biological parameters, including field
signal characteristics (frequency, amplitude, wave
shape, etc.), duration of exposure, cell metabolic
state, genotype, and how long cells are allowed to
grow before, during, and after exposure.
This work which aimed to investigate the effects of
Radiofrequency radiation from telecommunication
base stations on bacteria diversity and antibiotic
resistance of surrounding bacteria micro-flora have
shown that radiation influences and selected bacteria
of specific morphology (rod-like and gram positive),
imposes stress detrimental to various non-spore
forming, gram negative bacteria of non-rod
morphology and possibly may contribute to antibiotic
resistance. Further research in this area is advised
with the possibility of development of necessary
hazard control measures for the protection of the
environment from outbreak of antibiotic resistant
organisms.
0
20
40
60
80
100
120
PEF
CN
APX
Z
AM
R
CPX
S
SXT
E
PERCENTAGE RESISTANCE
ANTIBIOTICS TESTED
Bacillus spp
Clostridium spp
Corynebacterium
striatum
Sporosarcina ureae
Effect of Radiofrequency Radiation from Telecommunication Base Stations on Microbial Diversity and Antibiotic Resistance 673
E.A, ADEBAYO1; A.O, ADEEYO*1; A.A, AYANDELE1; I.O, OMOMOWO1
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... Several opportunistic bacterial pathogens with multidrug resistance were identified in the area of telecommunication stations [Adebayo et al., 2015]. Research in this area seems to be of big interest and mandatory in order to improve the measures of protection assessment against the occurrence of antibiotic-resistant organisms in the environment. ...
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  • Aug 2021
The hazardous consequences of electromagnetic field (EMF) exposure represent a public health concern. Common sources of EMF include smartphones and wireless fidelity (Wi-Fi). The aim of our study is to assess whether exposure to Wi-Fi radiofrequency radiation influences the pathogenic traits of carbapenem-resistant Klebsiella pneumoniae. The susceptibility to antibiotics was evaluated by the determination of minimum inhibitory concentrations (MIC). In this study, K. pneumoniae showed a non-linear response to treatments with Colistin and Gentamycin following different Wi-Fi exposure periods. Transmission electron microscopy revealed morphological changes in the bacterial cell membrane within 24 h of Wi-Fi exposure. Crystal violet quantification and quantitative real-time polymerase chain reaction showed that the ability to form biofilms was greater in Wi-Fi exposed K. pnemoniae when compared to control. Moreover, higher levels of bcsA, mrkA, and luxS messenger RNAs were observed. Our data suggest that Wi-Fi exposure can influence bacteria in a stressful way, leading to an alteration in their antibiotic susceptibility, morphological changes, and cumulative biofilm formation. © 2021 Bioelectromagnetics Society.
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... Many studies reported that mobile phone radiation (MPR) is a highly biological stressor that negatively affect all livestock's health by an oxidative stress (Nazıroğlu et al., 2013), these surrounding electromagnetic radiation (EMR) that compulsorily produced from using of technologies in all fields especially its application and networking even in farm management, subjecting our environment to huge source of EMR which in turn affect human health (Adebayo et al., 2014), domestic animals (Ebrahimi et al., 2018;Everaert and Bauwens, 2007;Hässig et al., 2014), (Wenzel et al., 2002) noted the abnormal behavior in cattle such as lying, pasture and ruminating behaviors as daily behavior profile, also there are the other notable effects recorded in poultry as embryo mortality especially between 9 th and 12 th days of incubation (Batellier et al., 2008), chicks myocardium pathological changes, DNA damage and increased mortality (Ye et al., 2016), these impacted effect also included the wild livestock in form of animal populations decline and deterioration (Balmori, 2009). The biological analyses to these effects explained various effects include anxiety-like behaviors and oxidative stress (Shehu et al., 2016) so a number of studies have concerned to EMR hazards, reported that EMR affects mainly the brain causing neural damage (Hussein et al., 2016), disturbed permeability of blood-brain barrier BBB (Sirav and Seyhan, 2016;Sırav and Seyhan, 2016), affected memory performance (Brzozek et al., 2018), Increasing incidence of the carcinogenic potentiality especially the heart and brain tumors (Falcioni et al., 2018), disturbed urogenital function (Türedi et al., 2017), decreasing the reproductive capacity of both males (Gautam et al., 2019) and females (Shahin et al., 2017), induced hormonal disturbance (Asl et al., 2019;Stephen et al., 2019) and liver damage (Moradpour et al., 2020). ...
THE DELETERIOUS EFFECTS OF MOBILE PHONE RADIATION (900 MHZ) ON BEHAVIOR PROFILE OF MICE: THE EFFECT OF ALTERNATIVE THERAPY IN NEUROPROTECTION
Article
Full-text available
  • Jan 2021
The cognition is a very critical process even for animals, enables them to recognize each other, their owner, feeding space requirement and help them in the vital behaviors as mate choice, foraging, on the other hand, the surrounded mobile phone radiation (MPR)and its increased application even for animal farms management and feeding can radiate inside the farms leading to the threaten animals’ health especially vital organs so this will reflect negatively on the farm income. Our study aimed to evaluate the effect of some famous historical architectural shapes on cognitive state and spatial memory impairment induced by effects of the mobile phone radiation, (900 MHz) for 8 weeks and possibility to create healthy and high efficient architectural farm designs. Thirty-two (32) Swiss Albino male mice were randomly divided into 8 groups (n = 8), they housed in 4 cages with various shapes. Group I & II housed in a traditional cage, Group I served as a control which did not subject to a mobile phone but groups (II-IV) are exposed to mobile phone radiations. Our result revealed that these changes in architectural shapes as housing in pyramid shape can induce positive effects on cognitive state and spatial memory impairment induced by MPR, it also retains the antioxidant capacity total antioxidant (TAC), malondialdehyde (MDA) and nitric oxide (NO), reduced glutathione (GSH), catalase (CAT) plus it alleviate the neurodegenerative effect of MPR on hippocampus and cortex in histopathology, it concluded that housing under pyramidal architectural shape may have a positive effect on cognition and spatial memory impairment induced by the hazard of electromagnetic waves and this study can be useful for architects and advised to be used in the creation of healthy architecture buildings for either human or animal farms.
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... In latest decade uses of technologies in all fields are increasingly day after day, especially the use of mobile phones, its application and networking that subjecting our environment to huge source of electromagnetic radiation (EMR) that in turn negatively affect human health (Adebayo et al., 2015), so number of studies have concerned to report EMR hazard effects and displayed that EMR affect mainly brain causing nerve cell damage (Salford et al., 2003), altering blood-brain barrier permeability (S1rav and Seyhan, 2016), impaired memory performance (Ahmadi et al., 2018), deterioration in behavioral and cognitive processesin both humans and prolonged exposure of animals (Cassel et al., 2004;Söderqvist et al., 2015;Zhao et al., 2012), Increasing incidence of the heart and brain tumors (Falcioni et al., 2018;Finnie et al., 2006) but also due to its oxidizing effects can impair oxidant and antioxidant balance (Irmak et al., 2002), decreasethe reproductive capacity (Chavdoula et al., 2010), hormonal disturbance (Yüksel et al., 2016;Lin et al., 2018) and hepatic damage (Qi et al., 2015). ...
THE HEPATOTOXIC EFFECTS OF MOBILE PHONE RADIATION (900 MHZ) ON MALE MICE AND THE HEPATOPROTECTIVE POTENTIALS OF ARCHITECTURAL SHAPES OF CAGES
Article
Full-text available
  • Dec 2020
Advances in technology, industry, economy and researches forced all people to continuous use of rapidly increased application of microwave (MW) radiation especially Wireless communication systems that is used daily in telecommunication, on line learning, medicine and even for animal farms management, these radiation uses always happen inside the buildings such as houses, schools, hospitals, offices, farms and public places leading to the threaten people's and animals' health especially vital organs and so this will reflect negatively on investment. Our study aimed to evaluate the possibility of new trends in hepatoprotection by potentiality of some famous historical architectural shapes as a physical protector against the harmful effects of the mobile phone radiation MPR, (900 MHz) for 8 weeks and to create healthy and high efficient architectural environments. Thirty-six (36) Swiss Albino male mice were randomly divided into 6 groups (n = 6), they housed in 6 cages with various shapes to assess the hepatoprotective effects of against MPR. Group I & II housed in a traditional cage, Group I served as a control which did not subjected to mobile phone but groups (II-VI) are exposed to mobile phone radiations. Our result revealed that these changes in architectural shapes (especially pyramid, bio-geometry and hexagonal shapes) can decreased the elevated hepatic enzymes either serum transaminases (ALT, AST) or alkaline phosphatase (ALP) in comparison to positive control groups and also restore the antioxidant capacity (total antioxidant (TAC), malondialdehyde (MDA) and nitric oxide (NO), reduced glutathione (GSH), catalase (CAT) plus retain the normal hepatic architecture in histopathology, it concluded that some specific architectural shapes may protect the liver from hazard of electromagnetic waves and this study can be useful for architects and advised to be used in the creation of healthy architecture buildings for either human or animal farms.
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... In latest decade uses of technologies in all fields are increasingly day after day, especially the use of mobile phones, its application and networking that subjecting our environment to huge source of electromagnetic radiation (EMR) that in turn negatively affect human health (Adebayo et al., 2015), so number of studies have concerned to report EMR hazard effects and displayed that EMR affect mainly brain causing nerve cell damage (Salford et al., 2003), altering blood-brain barrier permeability (S1rav and Seyhan, 2016), impaired memory performance (Ahmadi et al., 2018), deterioration in behavioral and cognitive processesin both humans and prolonged exposure of animals (Cassel et al., 2004;Söderqvist et al., 2015;Zhao et al., 2012), Increasing incidence of the heart and brain tumors (Falcioni et al., 2018;Finnie et al., 2006) but also due to its oxidizing effects can impair oxidant and antioxidant balance (Irmak et al., 2002), decreasethe reproductive capacity (Chavdoula et al., 2010), hormonal disturbance (Yüksel et al., 2016;Lin et al., 2018) and hepatic damage (Qi et al., 2015). ...
THE HEPATOTOXIC EFFECTS OF MOBILE PHONE RADIATION (900 MHZ) ON MALE MICE AND THE HEPATOPROTECTIVE POTENTIALS OF ARCHITECTURAL SHAPES OF CAGES
Article
Full-text available
  • Dec 2020
Advances in technology, industry, economy and researches forced all people to continuous use of rapidly increased application of microwave (MW) radiation especially Wireless communication systems that is used daily in telecommunication, on line learning, medicine and even for animal farms management, these radiation uses always happen inside the buildings such as houses, schools, hospitals, offices, farms and public places leading to the threaten people's and animals' health especially vital organs and so this will reflect negatively on investment. Our study aimed to evaluate the possibility of new trends in hepatoprotection by potentiality of some famous historical architectural shapes as a physical protector against the harmful effects of the mobile phone radiation MPR, (900 MHz) for 8 weeks and to create healthy and high efficient architectural environments. Thirty-six (36) Swiss Albino male mice were randomly divided into 6 groups (n = 6), they housed in 6 cages with various shapes to assess the hepatoprotective effects of against MPR. Group I & II housed in a traditional cage, Group I served as a control which did not subjected to mobile phone but groups (II-VI) are exposed to mobile phone radiations. Our result revealed that these changes in architectural shapes (especially pyramid, bio-geometry and hexagonal shapes) can decreased the elevated hepatic enzymes either serum transaminases (ALT, AST) or alkaline phosphatase (ALP) in comparison to positive control groups and also restore the antioxidant capacity (total antioxidant (TAC), malondialdehyde (MDA) and nitric oxide (NO), reduced glutathione (GSH), catalase (CAT) plus retain the normal hepatic architecture in histopathology, it concluded that some specific architectural shapes may protect the liver from hazard of electromagnetic waves and this study can be useful for architects and advised to be used in the creation of healthy architecture buildings for either human or animal farms.
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... -Besides plants, soil microflora is considerably affected by mobile phone radiofrequency radiations. A report was published on variations in microbial diversity and antibiotic resistance in microbes in response to RF radiations from telecommunication base stations (Adebayo et al., 2014). In this study it was reported that radiations create stress for non-sporulating, gram negative bacteria inducing them to form spores to prevent DNA damage. ...
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... Crude extracts of G. latifolium and Z. zanthoxyloides eluted by ethyl acetate and chloroform and freeze dried were prepared into solutions of different concentrations ranging between 25 and 500 mg/ml by dissolving appropriate amount of crystallised extracts in sterile deionised water. About 20 ml of extract solution corresponding to a range of (0.5 mg -10 mg) was then transferred on sterile 6 mm diameter sterile paper discs prior to antimicrobial sensitivity testing by disc diffusion method as described by (Adebayo et al., 2014;Lateef and Adeeyo, 2015). Briefly, 1 to 2 colonies of each bacteria culture were introduced into nutrient broth, and incubated at 37°C for 24 hrs. ...
Antimicrobial Potencies of Selected Native African Herbs against Water Mi‐ crobes
Article
Full-text available
  • Mar 2020
Antimicrobial potencies of some selected native Africa herbs
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... Moreover, there are indications that electromagnetic radiation could have a bio-physical effect on various animal and human organs. The organ exposure to electromagnetic radiation has shown that there are histological, hematological and histochemical changes which differ from normal [22][23][24]. In order to block the undesired EM radiation, one has to understand the electrical properties and EM behavior of structural materials. ...
Electrical Conductivity and Electromagnetic Shielding Effectiveness of Bio-Composites
Article
Full-text available
  • Mar 2020
In this paper, the electrical conductivity and electromagnetic shielding effectiveness of two bio-composites are studied by experimental testing and numerical models. Two monolithic composites with partly bio-based content were manufactured. The first bio-composite is made of a carbon fiber fabric prepreg and a partly bio-based (rosin) epoxy resin (CF/Rosin). The second bio-composite is a combination of prepregs of carbon fiber fabric/epoxy resin and flax fiber fabric/epoxy resin (CF-Flax/Epoxy). A single line infusion process was used prior to the curing step in the autoclave. Both variants are exemplary for the possibility of introducing bio-based materials in high performance CFRP. In-plane and out-of-plane electrical conductivity tests were conducted according to Airbus standards AITM2 0064 and AITM2 0065, respectively. Electromagnetic shielding effectiveness tests were conducted based on the standard ASTM D 4935-10. Materials were prepared at the German Aerospace Center (DLR), while characterization tests were conducted at the University of Patras. In addition to the tests, numerical models of representative volume elements were developed, using the DIGIMAT software, to predict the electrical conductivity of the two bio-composites. The preliminary numerical results show a good agreement with the experimental results.
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... Crude extracts of G. latifolium and Z. zanthoxyloides eluted by ethyl acetate and chloroform and freeze dried were prepared into solutions of different concentrations ranging between 25 and 500 mg/ml by dissolving appropriate amount of crystallised extracts in sterile deionised water. About 20 ml of extract solution corresponding to a range of (0.5 mg -10 mg) was then transferred on sterile 6 mm diameter sterile paper discs prior to antimicrobial sensitivity testing by disc diffusion method as described by (Adebayo et al., 2014;Lateef and Adeeyo, 2015). Briefly, 1 to 2 colonies of each bacteria culture were introduced into nutrient broth, and incubated at 37°C for 24 hrs. ...
Antimicrobial Potencies of Selected Native African Herbs against Water Microbes
Article
Full-text available
  • Mar 2020
Purpose Phyto-active components of Zanthoxylum zanthoxyloides and Gongronema latifolium was investigated against water microbial contaminants for possible novel antimicrobial usage in water treatment. Method Crude ethyl acetate and chloroform fractions of Zanthoxylum zanthoxyloides and Gongronema latifolium were prepared and screened for antimicrobial and phytochemical profiles using standard methods. Results Crude extracts of the different plant examined selectively comprise saponins, tannins, reducing sugars, anthraquinones, flavonoids, terpenoids, phlobatanins and alkaloids. All plant extracts showed broad spectrum antibiosis against E. coli, P. aeruginosa, Klebsiella sp, S. pneumoniae and B. cereus, as well as A. niger, A. flavus, Trichoderma sp and Candida sp. Chloroform extracts compared well than ethyl acetate extracts. Conclusion This work represents the first report to direct the possible application of Zanthoxylum zanthoxyloides and Gongronema latifolium to potential application in water. Overall results revealed that antimicrobial activities are dose and plant dependent. Noteworthy is the comparatively greater antimicrobial activity of crude extracts over commercial antibiotics used at the concentration of extracts tested. These plants can therefore serve as a potent source of natural water disinfectant.
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... It has been well established that exposure to RF-MWs can make microorganisms resistant to antibiotics. (Adebayo et al. 2014;Taheri et al. 2017;Mortazavi 2018). There is no gainsaying that this adaptive phenomenon constitutes a very serious potential threat to human health. ...
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... The prolonged EMF exposure resulted in major effects in K. pneumonia before they reach an adaptation stage 5 . Some bacteria with resistance to multidrugs were detected in the vicinity of telecommunication stations 28 . Furthermore, the microbial growth of human skin microbiota was disrupted after exposure to radiofrequency EMF (RF-EMF) 29 . ...
Global gene expression analysis of Escherichia coli K-12 DH5α after exposure to 2.4 GHz wireless fidelity radiation
Article
Full-text available
  • Oct 2019
This study investigated the non-thermal effects of Wi-Fi radiofrequency radiation of 2.4 GHz on global gene expression in Escherichia coli K-12 DH5α. High-throughput RNA-sequencing of 2.4 GHz exposed and non-exposed bacteria revealed that 101 genes were differentially expressed (DEGs) at P ≤ 0.05. The up-regulated genes were 52 while the down-regulated ones were 49. QRT-PCR analysis of pgaD, fliC, cheY, malP, malZ, motB, alsC, alsK, appB and appX confirmed the RNA-seq results. About 7% of DEGs are involved in cellular component organization, 6% in response to stress stimulus, 6% in biological regulation, 6% in localization, 5% in locomotion and 3% in cell adhesion. Database for annotation, visualization and integrated discovery (DAVID) functional clustering revealed that DEGs with high enrichment score included genes for localization of cell, locomotion, chemotaxis, response to external stimulus and cell adhesion. Kyoto encyclopedia of genes and genomes (KEGG) pathways analysis showed that the pathways for flagellar assembly, chemotaxis and two-component system were affected. Go enrichment analysis indicated that the up-regulated DEGs are involved in metabolic pathways, transposition, response to stimuli, motility, chemotaxis and cell adhesion. The down-regulated DEGs are associated with metabolic pathways and localization of ions and organic molecules. Therefore, the exposure of E. coli DH5α to Wi-Fi radiofrequency radiation for 5 hours influenced several bacterial cellular and metabolic processes.
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Non-thermal Biological Effects of Microwaves
Article
Full-text available
  • Jan 2005
The aim of this paper is to overview the diverse biological effects of non-thermal microwaves (NT MWs) and complex dependence of these effects on various physical and biological parameters. Besides dependencies on frequency and modulation, the available data suggest dependencies of the NT MW effects on intermittence and coherence time of exposure, polarization, static magnetic filed, electromagnetic stray field, genotype, gender, physiological and individual factors, cell density during of exposure and indicate that duration of exposure may be not less important than power density (PD) for the NT MW effects. Further evaluation of these dependencies are needed for understanding the mechanisms by which NT MWs affect biological systems, planning in vivo and epidemiological studies, developing medical treatments, setting safety standards, and minimizing the adverse effects of MWs from mobile communication.
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Antibiotic resistance pattern of isolated bacterial from salads
Article
Full-text available
  • Oct 2012
The antibiotic resistance pattern of bacterial isolates from salad samples sold in a re-known food industry in different parts of Nigeria was investigated. A total of twenty-five bacterial isolates of six genera were encountered in the following proportion: Pseudomonas spp. (36%), Bacillus spp. (24%); Escherichia coli (16%), Proteus spp. (12%), Enterobacter spp. (8%) and Aeromonas hydrophila (4%). The antibiotic resistance pattern of the isolates revealed that resistance to eleven of the twelve antibiotic tested were above 50%. Streptomycin (44%) was the only antibiotic with resistance rate below this range. Resistance to Augmentin was the highest (96%), followed by Cotrimoxazole (92%) and Nitrofurantoin (88%). The results suggest the need for intensive surveillance of isolates throughout salad production continuum to prevent food-borne infections and also to detect emerging antimicrobial resistance phenotypes.
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Soil beneficial bacteria and their role in plant growth promotion: A Review
Article
Full-text available
Soil bacteria are very important in biogeochemical cycles and have been used for crop production for decades. Plant–bacterial interactions in the rhizosphere are the determinants of plant health and soil fertility. Free-living soil bacteria beneficial to plant growth, usually referred to as plant growth promoting rhizobacteria (PGPR), are capable of promoting plant growth by colonizing the plant root. PGPR are also termed plant health promoting rhizobacteria (PHPR) or nodule promoting rhizobacteria (NPR). These are associated with the rhizosphere, which is an important soil ecological environment for plant–microbe interactions. Symbiotic nitrogen-fixing bacteria include the cyanobacteria of the genera Rhizobium, Bradyrhizobium, Azorhizobium, Allorhizobium, Sinorhizobium and Mesorhizobium. Free-living nitrogen-fixing bacteria or associative nitrogen fixers, for example bacteria belonging to the species Azospirillum, Enterobacter, Klebsiella and Pseudomonas, have been shown to attach to the root and efficiently colonize root surfaces. PGPR have the potential to contribute to sustainable plant growth promotion. Generally, PGPR function in three different ways: synthesizing particular compounds for the plants, facilitating the uptake of certain nutrients from the soil, and lessening or preventing the plants from diseases. Plant growth promotion and development can be facilitated both directly and indirectly. Indirect plant growth promotion includes the prevention of the deleterious effects of phytopathogenic organisms. This can be achieved by the production of siderophores, i.e. small metal-binding molecules. Biological control of soil-borne plant pathogens and the synthesis of antibiotics have also been reported in several bacterial species. Another mechanism by which PGPR can inhibit phytopathogens is the production of hydrogen cyanide (HCN) and/or fungal cell wall degrading enzymes, e.g., chitinase and ß-1,3-glucanase. Direct plant growth promotion includes symbiotic and non-symbiotic PGPR which function through production of plant hormones such as auxins, cytokinins, gibberellins, ethylene and abscisic acid. Production of indole-3-ethanol or indole-3-acetic acid (IAA), the compounds belonging to auxins, have been reported for several bacterial genera. Some PGPR function as a sink for 1-aminocyclopropane-1-carboxylate (ACC), the immediate precursor of ethylene in higher plants, by hydrolyzing it into α-ketobutyrate and ammonia, and in this way promote root growth by lowering indigenous ethylene levels in the micro-rhizo environment. PGPR also help in solubilization of mineral phosphates and other nutrients, enhance resistance to stress, stabilize soil aggregates, and improve soil structure and organic matter content. PGPR retain more soil organic N, and other nutrients in the plant–soil system, thus reducing the need for fertilizer N and P and enhancing release of the nutrients.
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Essay: Tackling antibiotic resistance
Article
Full-text available
  • Nov 2011
The development and spread of antibiotic resistance in bacteria is a universal threat to both humans and animals that is generally not preventable but can nevertheless be controlled, and it must be tackled in the most effective ways possible. To explore how the problem of antibiotic resistance might best be addressed, a group of 30 scientists from academia and industry gathered at the Banbury Conference Centre in Cold Spring Harbor, New York, USA, from 16 to 18 May 2011. From these discussions there emerged a priority list of steps that need to be taken to resolve this global crisis.
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The effect of electromagnetic field on protein molecular structure of E. coli and its pathogenesis
Article
  • Jan 2008
Effects of electromagnetic field 50 Hz frequency and strength 2 mT on each of growth characteristics and pathogenicity of E. coli cells have been studied. Also, the changes in the molecular structure of water soluble protein (WSP) extracted from E. coli bacteria exposed to demonstrated magnetic field were investigated through measuring each of their dielectric relaxation in the frequency range 1 kHz → 4 MHz at 4±0.05 ºC and molecular weight distribution using SDS polyacrylamide gel electrophoresis. In addition the absorption spectra of the WSP were measured at wavelength range 300-350 nm. Equal volumes of E. coli suspension were exposed to magnetic field for different periods. Most effective periods, namely of 6 and 16 h, were chosen for all our experimental studies (direct and late effect - 2 h). The results indicated that there are pronounced changes in the growth characteristic curve, where suppressive effect was observed on the cell growth. Number of cells at stationary phase markedly decreased after exposure period of 6 h, but there was a slight increase in the cells number at stationary phase after an exposure period of 16 h. Further, more remarkable changes happened in the molecular structure of extracted protein molecules after exposure periods, 6 and 16 h such as average molecular radii, shape, relaxation time and dielectric increment. Also, there were sharp decreases in the number of protein bands and in their protein amount after an exposure period of 6 h. However, after an exposure period of 16 h, number of protein bands and protein amount increased relative to the unexposed cells. Mortality rate recorded after injection with E. coli suspension exposed to 6 h was 40%, but after an exposure period of 16 h it was 80%.
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The Influence of Alternating Magnetic Field on Escherichia coli Bacterial Cells
Article
  • Aug 2005
The effect of a low-frequency alternating magnetic field on the properties of E. coli bacterial cells in an aqueous medium have been studied in vitro. The experiments were performed with a daily grown culture of E. coli HB-101 cells obtained in a liquid LB medium. The samples were prepared by means of turbidity-controlled serial dilutions and then grown on a bactoagar. It is established that E. coli colonies grown upon exposure of a monolayer of cells in the alternating magnetic field had a smaller average diameter than the colonies not treated in the field. The number of cell colonies was increased, which indicated that the treatment of E. coli cells in a low-frequency magnetic field produced stimulation of the cell growth.
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Effect of extremely low frequency magnetic field exposure on DNA transposition in relation to frequency, wave shape and exposure time
Article
To examine the effect of extremely low frequency magnetic field (ELF-MF) exposure on transposon (Tn) mobility in relation to the exposure time, the frequency and the wave shape of the field applied. Two Escherichia coli model systems were used: (1) Cells unable to express β-galactosidase (LacZ(-)), containing a mini-transposon Tn10 element able to give ability to express β-galactosidase (LacZ(+)) upon its transposition; therefore in these cells transposition activity can be evaluated by analysing LacZ(+) clones; (2) cells carrying Fertility plasmid (F(+)), and a Tn5 element located on the chromosome; therefore in these cells transposition activity can be estimated by a bacterial conjugation assay. Cells were exposed to sinusoidal (SiMF) or pulsed-square wave (PMF) magnetic fields of various frequencies (20, 50, 75 Hz) and for different exposure times (15 and 90 min). Both mini-Tn10 and Tn5 transposition decreased under SiMF and increased under PMF, as compared to sham exposure control. No significant difference was found between frequencies and between exposure times. ELF-MF exposure affects transposition activity and the effects critically depend on the wave shape of the field, but not on the frequency and the exposure time, at least in the range observed.
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Toxicity and SOS-response to ELF magnetic fields and nalidixic acid in E. coli cells
Article
Extremely low-frequency magnetic fields (ELF-MF) have previously been shown to affect conformation of chromatin and cell proliferation. Possible genotoxic and carcinogenic effects of ELF-MF have also been discussed and tested. In this study, we analysed the effect of ELF-MF on chromatin conformation in E. coli GE499 cells by the anomalous viscosity time-dependence (AVTD) technique. Possible genotoxic effects of the specific combination of static and ELF-MF, which has been proven to affect chromatin conformation, were investigated by a clonogenic assay, by assessing cell-growth kinetics, and by analysis of the SOS-response by means of inducible recA-lacZ fusion-gene products and the β-galactosidase assay. The genotoxic agent nalidixic acid (NAL) was used as a positive control and in combination with ELF-MF. Nalidixic acid at 3-30μg/ml decreased the AVTD peaks and induced a cytotoxic effect. In contrast to NAL, ELF-MF fields increased AVTD, stimulated cell growth, and increased cloning efficiency. These effects depended on the frequency within the range of 7-11Hz. While NAL induced an SOS-response, exposure to ELF-MF did not induce the recA-lacZ fusion-gene product. Exposure to ELF-MF did not modify the genotoxic effects of NAL either. All together, the data show that ELF-MF, under specific conditions of exposure, acted as a non-toxic but cell-growth stimulating agent.
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