Hakan Aydogan

Publications of Hakan Aydogan

• Staphylococcal cassette chromosome mec (SCCmec) characterization and panton-valentine leukocidin gene occurrence for methicillin-resistant Staphylococcus aureus in Turkey, from 2003 to 2006.

  Authors: Abdullah Kilic, Aylin Guclu, Zeynep Senses, Orhan Bedir, Hakan Aydogan, A Basustaoglu

  Antonie van Leeuwenhoek. 09/2008;

  Methicillin-resistant Staphylococcus aureus (MRSA) cause serious community-acquired and nosocomial diseases all over the world. We determined the SCCmec types and occurrence of the PVL gene by usingMethicillin-resistant Staphylococcus aureus (MRSA) cause serious community-acquired and nosocomial diseases all over the world. We determined the SCCmec types and occurrence of the PVL gene by using TaqMan real-time PCR method, and correlated these with phenotypic antibiotic susceptibility patterns for MRSA strains collected from Gulhane Military Medical Academy Hospital (GMMAH) during 4 years study period. To our knowledge, this is the first report from Turkey of molecular SCCmec typing analysis of MRSA stains. A total of 385 clinical MRSA isolates collected in the clinical and Microbiology Laboratory at GMMAH between 2003 and 2006 were included in the study. Overall, SCCmec types-I, II, III, IV, V, nontypeable and PVL occurrence were detected in 11 (2.8%), 3 (0.8%), 316 (82.1%), 20 (5.1%), 20 (5.1%), 15 (3.9%) and 5 (1.3%) isolates, respectively. A total of 330 (85.5%) were SCCmec-I/II/III and 40 (10.3%) were SCCmec IV/V. SCCmec-I/II/III isolates were recovered more from patients with serious infections in surgical departments especially those with intensive care units than the SCCmec-IV/V isolates (chi(2) = 13.560, P < 0.001). SCCmec-I/II/III MRSA strains were predominantly recovered from blood stream (53.0%, P = 0.014), while SCCmec-IV/V strains were predominately isolated from skin and soft tissue and abscess (55.0%, P < 0.001). The PVL gene was detected in 10.0% of SCCmec-IV/V isolates in contrast to 0.3% in SCCmec-I/II/III (chi(2) = 25.164, P < 0.001). SCCmec-I/II/III MRSA strains were more resistant to clindamycin (chi(2) = 5.078, P = 0.024), amoxicillin-clavulanate (chi(2) = 84.912, P < 0.001), erythromycin (chi(2) = 4.651, P = 0.031), gentamicin (chi(2) = 24.869, P < 0.001), and rifampin (chi(2) = 18.878, P < 0.001) than SCCmec-IV/V MRSA strains. This data indicates that SCCmec-III MRSA strains that do not carry the PVL gene are the predominant MRSA strains in our hospital setting in Ankara, capital of Turkey and that SCCmec-I/II/III MRSA strains may cause serious infections in surgical departments especially those with intensive care units.

• Molecular characterization of methicillin-resistant Staphylococcus aureus nasal isolates from Turkey.

  Authors: Abdullah Kilic, Gurkan Mert, Zeynep Senses, Orhan Bedir, Hakan Aydogan, A Basustaoglu, Peter Appelbaum

  Antonie van Leeuwenhoek. 09/2008;

  Methicillin-resistant Staphylococcus aureus (MRSA) colonize most frequently in the anterior nares of the nose and cause serious infections all over the world. The aim of this study was to determineMethicillin-resistant Staphylococcus aureus (MRSA) colonize most frequently in the anterior nares of the nose and cause serious infections all over the world. The aim of this study was to determine the nasal carriage rate of S. aureus and MRSA strains in Turkish elementary school children. We also analyzed molecular characterizations of MRSA strains by using pulse field gel electrophoresis (PFGE), multi locus sequence typing (MLST), staphylococcal chromosomal cassette mec (SCCmec) typing, and detection of the Panton-valentine leucocidin (PVL) gene. The nasal swabs were obtained from 4,050 children during a 4 month period in Ankara. In vitro antimicrobial susceptibility testing to 1 mug oxacillin and 30 mug cefoxitin was determined by a disk diffusion method. We found that the 1,001 of 4,050 (24.7%) children were colonized with S. aureus. Three S. aureus strains were resistant to oxacillin and cefoxitin. The rate of MRSA among all children was 0.07%. The MRSA strains revealed three different PFGE pattern. All MRSA isolates by harbored the SCCmec type IV element, but not the PVL gene. The two MRSA isolate belonged to sequence type (ST) 30, whereas the other one was a unique type. The results of this study demonstrated that S. aureus nasal carriage rate was consistent with previous studies. However, MRSA carriage rate was low. This study also indicated that the ST30-type IV without PVL gene MRSA clone may be expected to spread in Turkish community.

• Acinetobacter septicus sp. nov. association with a nosocomial outbreak of bacteremia in a neonatal intensive care unit.

  Authors: Abdullah Kilic, Haijing Li, Alexander Mellmann, Ahmet C Basustaoglu, Mustafa Kul, Zeynep Senses, Hakan Aydogan, Charles W Stratton, Dag Harmsen, Yi-Wei Tang

  Journal of clinical microbiology. 04/2008; 46(3):902-8.

  Acinetobacter species other than Acinetobacter baumannii have rarely been reported to be associated with nosocomial outbreaks of bloodstream infections. Within a period of 1 week, sevenAcinetobacter species other than Acinetobacter baumannii have rarely been reported to be associated with nosocomial outbreaks of bloodstream infections. Within a period of 1 week, seven Acinetobacter-like isolates were recovered from peripheral blood and catheter specimens of five patients at a neonatal intensive care unit (NICU) in a tertiary hospital in Turkey. All five patients had placement of central venous catheters and had received total parenteral nutrition before the onset of bacteremia. Two of the five patients died. Medical devices, tap water, aerators, water samples, various surfaces, intravenous fluids, and the hands of health care workers in the NICU were sampled and were culture negative for the bacterium. All seven of the isolates had identical biochemical reactions, antimicrobial susceptibility results, and pulsed-field gel electrophoresis patterns, indicating a clonal nosocomial outbreak. A panel of standard biochemical reaction profiles and three phenotypic commercial identification systems failed to identify these isolates. Phenotypically, the isolate differed from Acinetobacter ursingii by its hemolysis on sheep blood agar and its negative citrate utilization. Sequences of the full 16S rRNA gene, which contained at least three different gene copies with polymorphic sequences between nucleotide positions 70 and 206, were determined from the first recovered isolate. The complete 1,529- to 1,531-bp 16S rRNA gene sequences and partial 801-bp rpoB gene sequences had similarities of 99.5% and 97.2%, respectively, to an A. ursingii isolate. The DNA-DNA similarities of the strain against the type strain of A. ursingii were 64.7 and 68.7%, which were lower than the recommended threshold value of 70% for the definition of bacterial species. These data indicate that a novel Acinetobacter organism caused the nosocomial outbreak of bacteremia in the NICU unit. We propose the designation of Acinetobacter septicus sp. nov. for these isolates, with isolate AK001 as the type strain.

• Nosocomial outbreak of Sphingomonas paucimobilis bacteremia in a hemato/oncology unit.

  Authors: Abdullah Kilic, Zeynep Senses, A Emin Kurekci, Hakan Aydogan, Kenan Sener, Erol Kismet, A Celal Basustaoglu

  Japanese journal of infectious diseases. 12/2007; 60(6):394-6.

  Nosocomial Sphingomonas paucimobilis infections can arise from contaminated water and the contaminated hands of hospital staff. Within a 1-month period, we isolated six S. paucimobilis strains,Nosocomial Sphingomonas paucimobilis infections can arise from contaminated water and the contaminated hands of hospital staff. Within a 1-month period, we isolated six S. paucimobilis strains, including four from blood cultures of four patients and two from hospital environment specimens including tap water and a bathtub in a hemato/oncology unit. We described here these strains' molecular epidemiological analyses by pulsed-field gel electrophoresis (PFGE) and antibiotic susceptibilities by E-test. Although clinical and environmental isolates yielded three different antibiotic resistances and PFGE patterns, all four clinical strains had an identical pattern by both methods. Thus, the isolated clinical strain clone could be traced neither to health care workers nor to environmental samples. It was concluded that S. paucimobilis strains can cause outbreaks in hemato/oncology units. We did not demonstrate genetic relatedness between clinical and environmental isolates by PFGE, but did find PFGE a useful identification technique for epidemiological investigation.

• Comparative sporicidal effects of disinfectants after release of a biological agent.

  Authors: Levent Kenar, Mesut Ortatatli, Hakan Yaren, Turan Karayilanoglu, Hakan Aydogan

  Military medicine. 07/2007; 172(6):616-21.

  Because of spore formation, Bacillus anthracis is considered the most resistant biological warfare agent known. The present study aimed to assess and compare well-known decontamination routes toBecause of spore formation, Bacillus anthracis is considered the most resistant biological warfare agent known. The present study aimed to assess and compare well-known decontamination routes to inactivate the spores on daily-use environmental tools contaminated previously. To simulate the agent, Bacillus atrophaeus was used. Various environmental samples (such as tile, fabric clothing, wood, protective suit, glass, paper, soil, water, plastic, and metal) that may be contaminated after a biological incident were used as test carriers and inoculated with B. atrophaeus. Sodium hypochlorite, free chlorine, autoclaving, ethylene oxide, hydrogen peroxide, ultraviolet irradiation, and boiling decontaminated the samples. Glutaraldehyde (2%) and free chlorine solution (10,000 mg/L) were also found to be effective in decontaminating the samples and are recommended as alternatives to the use of sodium hypochlorite solution. Soil, tile, paper, and metal were determined to be the most difficult materials to decontaminate. It was concluded that 5% hypochlorite adjusted with acetic acid might also be used for decontamination. Decontamination strategies to reduce contamination of the environment by biological warfare agents need to be applied to mitigate the number of victims, in terms of prominent characteristics like cost-effectiveness and user-friendliness.

• Augmentation mentoplasty with diced high-density porous polyethylene.

  Authors: Ali Gürlek, Cemal Frat, Hakan Aydogan, Mehmet Celik, Ayşe Ersöz-Oztürk, Hdr Klnç

  Plastic and reconstructive surgery. 03/2007; 119(2):684-91.

  BACKGROUND: Augmentation mentoplasty is a common procedure, applied especially in conjunction with rhinoplasty. Although various materials have been used for this procedure, diced high-density porousBACKGROUND: Augmentation mentoplasty is a common procedure, applied especially in conjunction with rhinoplasty. Although various materials have been used for this procedure, diced high-density porous polyethylene (Medpor) has not been used so far. The purpose of this study was to evaluate the use of diced high-density porous polyethylene in chin augmentation. METHODS: A subperiosteal pocket is prepared through submental incision. A high-density porous polyethylene block is diced into 1 x 1.5-mm pieces, to be placed into the subperiosteal pocket as much as needed by wrapping into oxidized cellulose (Surgicel). Immediately after the incision is closed, shaping with external massage is performed and an external bandage is applied. RESULTS: This procedure was performed in 20 patients, in addition to rhinoplasty, with a mean follow-up of 14 months (range, 8 to 20 months). Five to 14 mm of augmentation was achieved. There were no complications, except for early seroma formation in three patients, which required aspiration by syringe. It is easy to give shape to diced high-density porous polyethylene by means of massage 3 weeks after surgery. CONCLUSIONS: Diced high-density porous polyethylene in augmentation mentoplasty is cheap, easy to insert, and moldable by external massage, and has flexibility in conforming to the shape of the mandible. It also avoids all the disadvantages of monobloc implants, allowing postoperative ingrowth of fibrous tissues, precluding late displacement, and giving a natural feel to the reconstructed area.

• Beneficial effects of caffeic acid phenethyl ester (CAPE) on the ischaemia-reperfusion injury in rat skin flaps.

  Authors: Hakan Aydogan, Ali Gurlek, Hakan Parlakpinar, Ibrahim Askar, Aysun Bay Karabulut, Nilay Aydogan, Alpay Fariz, Ahmet Acet

  Journal of plastic, reconstructive & aesthetic surgery : JPRAS. 01/2007; 60(5):563-8.

  Reperfusion injury is a phenomenon that occurs when tissues are subjected to ischaemia for a variable period of time, after which they are reperfused. Many factors have been implicated in the causeReperfusion injury is a phenomenon that occurs when tissues are subjected to ischaemia for a variable period of time, after which they are reperfused. Many factors have been implicated in the cause of reperfusion injury including free radicals and neutrophils. Caffeic acid (3,4-dihydroxycinnamic acid) phenethyl ester (CAPE) is an active component of propolis from honeybee; it has anti-inflammatory and immunomodulatory properties, and protective effects against ischaemia-reperfusion (I/R) injury. We investigated the effects of CAPE on the survival of skin flaps in the rat. Eighteen Wistar rats were used, and randomly divided into three groups (n=6 rats each group): the control group (Group 1), ethanol group (Group 2), and CAPE group (Group 3). A caudally based rectangular flap, 3x10 cm in size, was elevated on the back of the rat, according to the method described by Khouri and colleagues. The flap was sutured back into its original place. In the control group, saline 0.2 ml/day was given intraperitoneally (i.p.). Five percent ethanol 0.2 ml/day was administered i.p. in the ethanol group, and CAPE 50 micromol/kg/day i.p. in the CAPE group. To observe the effects of CAPE, levels of malondialdehyde (MDA), nitric oxide (NO), glutathione (GSH), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) were measured from extracted skin tissue. Flap viability was evaluated seven days after the initial operation, measuring necrotic areas of flaps and total flap areas. MDA and NO levels were significantly decreased in CAPE group; and however, GSH, GSH-Px, and SOD enzyme activities were significantly increased in CAPE group. We believed that the CAPE had beneficial effects to improve the survival of skin flaps since it has antioxidative and anti-inflammatory properties, and protective effects against I/R injury.

• Evaluation of the BacT/ALERT and BACTEC 9240 automated blood culture systems for growth time of Brucella species in a Turkish tertiary hospital.

  Authors: Mehmet Baysallar, Hakan Aydogan, Abdullah Kilic, Ayten Kucukkaraaslan, Zeynep Senses, Levent Doganci

  Medical science monitor : international medical journal of experimental and clinical research. 08/2006; 12(7):BR235-8.

  BACKGROUND: The isolation of Brucella species from blood may be achieved by using classic culture techniques, but detection of the organism is difficult due to its slow growth. The time-to-detectionBACKGROUND: The isolation of Brucella species from blood may be achieved by using classic culture techniques, but detection of the organism is difficult due to its slow growth. The time-to-detection of Brucella can take up to 30 days using the Castaneda blood culture method. Automated blood culture systems have reduced the growth time of Brucella. MATERIAL/METHODS: In this report we would like to contribute our experience on detection time in the isolation of Brucella species from 33,039 blood culture sets using BacT/ALERT between 1995 and 2000 (13 isolates) and thereafter using both the BACTEC and BacT/ALERT systems (17 isolates). RESULTS: Thirty Brucella spp. (17 by both systems and 13 by BacT/ALERT only) were isolated from 33,039 blood culture sets between 1995 and 2002. Brucellae were recovered between 1.8 and 3.7 days (mean: 2.5 days) in the BacT/ALERT blood culture system and between 2.1 and 3.8 days (mean: 2.8 days) in BACTEC 9240 system. CONCLUSIONS: We concluded that the mean time-to-detection could be <or=3 days, which is considered rapid enough for starting appropriate evidence-based treatment in an endemic setting.

• Clinical presentations of chlamydial and non-chlamydial reactive arthritis.

  Authors: Ahmet Ozgül, Ismail Dede, Mehmet Ali Taskaynatan, Hakan Aydogan, Tunç Alp Kalyon

  Rheumatology international. 08/2006; 26(10):879-85.

  The aim of this study was to investigate the triggering micro-organisms and the clinical as well as laboratory differences between Chlamydial and non-chlamydial reactive arthritis (ReA) in aThe aim of this study was to investigate the triggering micro-organisms and the clinical as well as laboratory differences between Chlamydial and non-chlamydial reactive arthritis (ReA) in a prospective study on 98 patients with acute/subacute arthritis. An inciting organism was found in 42 patients. Eighteen of these were chlamydial. Fifty-seven percent of all ReA patients were carriers for HLA-B27, which increased to 67% in the chlamydial group. Chlamydial ReA patients had more urethritis (P<0.05) with a longer period between arthritis and inciting infection, significantly lower CRP levels, and involved joint counts (P<0.05). Additionally, sacroiliitis was more frequent besides extra-articular manifestations in chlamydial ReA group. This study shows that chlamydial ReA differs in some points from non-chlamydial ReA, which in turn may affect the evaluation of an arthritic patient. ReA due to chlamydia more frequently encompasses a monoarticular or oligoarticular clinical picture with predominant distal extremity involvement. Non-chlamydial ReA presents higher joint counts and may involve upper extremity joints.

• The protective effect of melatonin on ischemia-reperfusion injury in the groin (inferior epigastric) flap model in rats.

  Authors: Ali Gurlek, Mehmet Celik, Hakan Parlakpinar, Hakan Aydogan, Aysun Bay Karabulut

  Journal of pineal research. 06/2006; 40(4):312-7.

  Inadequate blood perfusion and ischemia-reperfusion (I/R) injury in the surgical skin flap are believed to be the major factors that cause harmful changes within the tissue and vasculature, resultingInadequate blood perfusion and ischemia-reperfusion (I/R) injury in the surgical skin flap are believed to be the major factors that cause harmful changes within the tissue and vasculature, resulting in flap necrosis. Reactive oxygen radical species (ROS), in part, are believed to play an important role in this injury. Melatonin, in many physiological conditions, has been shown to have direct and indirect antioxidative effects and free-radical-scavenging properties. Therefore, it may have a beneficial effect on I/R-induced flap injury. In this study, the possible protective effects of melatonin were investigated in I/R injury of rat epigastric (axial pattern) flaps. Ischemia was achieved for 12 h by occlusion of inferior epigastric artery. Melatonin or vehicle was administered 1 h before flap elevation and was continued for 6 days after ischemia. I/R injury elevated malondialdehyde (MDA), an end product of lipid peroxidation, and nitric oxide (NO) levels while the glutathione (GSH) content was reduced. Myeloperoxidase (MPO) activity, which is known to be related to tissue neutrophil accumulation, was found to be statistically higher in the I/R group when compared with the sham group. Administration of melatonin significantly decreased MDA, NO and MPO levels and elevated the GSH content. Moreover, melatonin reduced the flap necrosis area, which was determined using a planimetric method. In conclusion, melatonin, a potent scavenger of free radicals, plays a major role in preventing the inferior epigastric arterial I/R-induced flap necrosis, based on planimetric flap survival and biochemical results. The beneficial effects of melatonin in I/R injury implies the involvement of free radicals in flap damage.

• Rapid and quantitative detection of Crimean-Congo hemorrhagic fever virus by one-step real-time reverse transcriptase-PCR.

  Authors: Mehmet Yapar, Hakan Aydogan, Alaaddin Pahsa, Bulent A Besirbellioglu, Hurrem Bodur, Ahmet C Basustaoglu, Cakir Guney, Ismail Y Avci, Kenan Sener, Mohammad H Abu Setteh, Ayhan Kubar

  Japanese journal of infectious diseases. 01/2006; 58(6):358-62.

  In this article, the development of a new TaqMan-based one-step real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assay for detection and quantification of Crimean-Congo hemorrhagicIn this article, the development of a new TaqMan-based one-step real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assay for detection and quantification of Crimean-Congo hemorrhagic fever virus (CCHFV) RNA is described. Selected oligos targeting the highly conserved S region of CCHFV were designed by using our oligo design and analysis software, Oligoware 1.0. None of the primer sequences showed genomic cross-reactivity with other viruses or cells in a BLAST (NCBI) search analysis. The sensitivity and specificity of the primers and the probe were tested using 18 serum samples from patients from East Anatolian who were suspected of having CCHFV, including 2 samples that had already been confirmed to be positive for CCHFV. Among the 16 previously unconfirmed samples, 5 were positive by TaqMan-based one-step real-time RT-PCR and 1 was positive by non-nested RT-PCR, and these results were confirmed with DNA sequencing analysis. The 2 previously confirmed CCHFV RNA samples were also positive by both TaqMan-based one-step real-time RT-PCR and non-nested RT-PCR tests. To ensure the quantitative reproducibility of TaqMan-based one-step real-time RT-PCR, the procedure was repeated several times and the same results were obtained (SD = 0.84 [maximum value]). The developed assay was able to sensitively quantify the concentration of CCHFV RNA, which ranged from 10(2) to 10(7) copies/ml per reaction, using plasmid standards generated from the CCHFV RNA (correlation coefficiency = 0.989). The results of the one-step real-time RT-PCR assay were more sensitive than those of the non-nested RT-PCR assay. It can be concluded that our one-step real-time RT-PCR assay is a reliable, reproducible, specific, sensitive and simple tool for the detection and quantification of CCHFV.

• Two cases of Ralstonia pickettii bacteremias in a pediatric oncology unit requiring removal of the Port-A-Caths.

  Authors: Erol Kismet, Abdullah Avni Atay, Erkan Demirkaya, Halil Ibrahim Aydin, Hakan Aydogan, Vedat Koseoglu, Erdal Gokcay

  Journal of pediatric hematology/oncology : official journal of the American Society of Pediatric Hematology/Oncology. 02/2005; 27(1):37-8.

  Ralstonia pickettii is an aerobic, gram-negative bacterium causing bacteremia following the use of contaminated saline vials, respiratory therapy solutions, skin disinfectants, blood culture mediums,Ralstonia pickettii is an aerobic, gram-negative bacterium causing bacteremia following the use of contaminated saline vials, respiratory therapy solutions, skin disinfectants, blood culture mediums, and water supplies. It is rarely associated with human infections. The authors report two cases of R. pickettii bacteremia in patients with Port-A-Caths that could be treated only by removal of the ports.

• Effect of mesalazine, metronidazole and gentamicin on bacterial translocation in experimental colitis.

  Authors: Cengizhan Yigitler, Bulent Gulec, Hakan Aydogan, Ayhan Ozcan, Metin Kilinc, Taner Yigit, Orhan Kozak, Mesut Pekcan

  Journal of gastroenterology and hepatology. 11/2004; 19(10):1179-86.

  BACKGROUND AND AIM: In inflammatory bowel disease it has been established that enteric microorganisms are present in the final stage of the active inflammatory process. The purpose of the presentBACKGROUND AND AIM: In inflammatory bowel disease it has been established that enteric microorganisms are present in the final stage of the active inflammatory process. The purpose of the present study was to investigate the effects of mesalazine, and metronidazole-gentamicin combination, on bacterial translocation in an animal colitis model. METHODS: Fifty rats were stratified into five groups. The control group (group NC) was given only 2 mL saline enema and the remaining four groups were given 2 mL acetic acid enema. Group CC was the diseased control group. The treatment regimens started on the fifth day: mesalazine enema in group MesC, metronidazole-gentamicin in group MGC, and mesalazine + metronidazole + gentamicin in group MesMGC. After death on day 10, 2.5-cm colonic segments from all groups were weighed separately. In all rats, histopathological scoring was done, and samples from feces, blood, liver and spleen underwent microbiological analyses. RESULTS: For all diseased rats, both mean weight loss and colonic segment weight/bodyweight ratio was significantly higher than that in the sham group. As compared with other groups, body and colonic segment changes as well as histopathological scoring in rats receiving mesalazine enema either solely or in combination with the antibiotics were lower. No bacterial growth was found in the blood, liver and spleen of the rats in the control group while enteric bacteria, mainly Escherichia coli (35%) were the most common bacteria translocated to that in the latter. Antibiotic combination, alone or in combination with mesalazine was effective in reducing the bacterial translocation while mesalazine administration did not properly influence its regression. CONCLUSIONS: Gram-negative enteric bacteria, predominantly E. coli, was the most common bacteria isolated in bacterial translocation occurring in acetic acid-induced colitis. This trial showed that mesalazine alone did not incorporate the reduction of infectious events, despite its beneficial effect on inflammatory changes in experimental colitis. Metronidazole and gentamicin combination given intraperitoneally was more effective than topical mesalazine in decreasing bacterial translocation.

• Linezolid and quinupristin/dalfopristin resistance in vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus prior to clinical use in Turkey.

  Authors: Mehmet Baysallar, Abdullah Kilic, Hakan Aydogan, Feriha Cilli, Levent Doganci

  International journal of antimicrobial agents. 06/2004; 23(5):510-2.

  The aim of this study was to determine the in vitro antimicrobial activity of recently licensed quinupristin/dalfopristin and linezolid which have not yet been in clinical use in Turkey againstThe aim of this study was to determine the in vitro antimicrobial activity of recently licensed quinupristin/dalfopristin and linezolid which have not yet been in clinical use in Turkey against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) strains isolated from various clinical specimens by using the Etest. The results showed that all MRSA strains were fully susceptible to both the new compounds. All strains were inhibited by 1 mg/l quinupristin/dalfopristin (mode MIC 0.38 mg/l) and by 3 mg/l linezolid (mode MIC 1.5 mg/l). Four strains of Enterococcus faecium showed an increase of resistance of 2-3 mg/l to quinupristin/dalfopristin (susceptible mode MIC 0.38 mg/l). With linezolid, all strains except two fell within the range 0.75-2.0 mg/l.

• Protective effect of melatonin on random pattern skin flap necrosis in pinealectomized rat.

  Authors: Ali Gurlek, Hakan Aydogan, Hakan Parlakpinar, Aysun Bay Karabulut, Mehmet Celik, Nurzen Sezgin, Ahmet Acet

  Journal of pineal research. 02/2004; 36(1):58-63.

  Random pattern skin flaps are still widely used in plastic surgery. However, necrosis in the distal portion resulting from ischemia is a serious problem, increasing the cost of treatment andRandom pattern skin flaps are still widely used in plastic surgery. However, necrosis in the distal portion resulting from ischemia is a serious problem, increasing the cost of treatment and hospitalization. Free oxygen radicals and increased neutrophil accumulation play an important role in tissue injury and may lead to partial or complete flap necrosis. To enhance skin flap viability, a variety of pharmacological agents have been intensively investigated. The aim of this study is to test the effects of melatonin, the chief secretory product of the pineal gland and a highly effective antioxidant, on random pattern skin flap survival in rats. Herein, to investigate the physiological and pharmacological role of melatonin on dorsal skin flap survival. Pharmacological (0.4, 4 and 40 mg/kg) levels of melatonin were given intraperitoneally (i.p.). For this, pinealectomized (Px) and sham operated (non-Px) rats were used. The effects of melatonin on levels of malondialdehyde (MDA), nitric oxide (NO), glutathione (GSH) and the activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were measured in the skin flap. The ratio of skin flap necrosis was compared among the experimental groups by using planimetry. MDA and NO levels were found to be higher in Px than non-Px rats; while GSH levels and GSH-Px, and SOD activities were reduced. Melatonin administration to Px rats reduced MDA and NO levels and increased GSH, GSH-Px, SOD levels. Melatonin also reduced the ratio of flap necrosis determined by using planimetry and supported through the photography. In conclusion, these results show that both physiological and pharmacological concentrations of melatonin improve skin flap viability.

• The effect of antibiotic and probiotic combination therapy on secondary pancreatic infections and oxidative stress parameters in experimental acute necrotizing pancreatitis.

  Authors: Sedat Akyol, M Refik Mas, Bilgin Comert, Umit Ateskan, Mehmet Yasar, Hakan Aydogan, Salih Deveci, Cemal Akay, Nuket Mas, Nuran Yener, I Hakki Kocar

  Pancreas. 06/2003; 26(4):363-7.

  INTRODUCTION: Ciprofloxacin and meropenem have effects on intestinal bacteria that are responsible for pancreatic infection, and on the basis of recent data it has been argued that probiotics,INTRODUCTION: Ciprofloxacin and meropenem have effects on intestinal bacteria that are responsible for pancreatic infection, and on the basis of recent data it has been argued that probiotics, especially those used in the food industry, could improve efforts to prevent and treat secondary pancreatic infections by inhibiting bacterial translocation. AIMS: To evaluate the effects of probiotic treatment alone or in combination with early administration of two different antibiotics on serum amylase, pancreatic histopathology, bacterial translocation, and oxidative markers. METHODOLOGY: Acute pancreatitis was induced in rats with 3% sodium taurocholate (1 mL/kg intraductally), except in group VI (sham group). After the stabilization period, the rats were divided into seven groups (n = 20) randomly. At hour 6 after injection, group I rats received probiotic Saccharomyces boulardii (25 mg/d orally q.d.), group II received meropenem (60 mg/kg intraperitoneally b.i.d.), group III received ciprofloxacin (40 mg/kg intraperitoneally b.i.d.), group IV received the same dose of probiotic plus meropenem, and group V received probiotic plus ciprofloxacin. Treatment was not given to group VI (sham group) and group VII (pancreatitis group). At hour 48 after induction, specimens were collected. RESULTS AND CONCLUSION: Although histopathologic scores in treatment groups were found to be lower than in group VII, the difference was statistically significant only in group V (p < 0.001). In evaluation of oxidative stress, we found that MDA levels decreased and SOD levels increased in treatment groups in comparison with levels in group VII. Probiotic treatment alone reduced bacterial translocation. Probiotic-antibiotic combination therapy was shown to improve histopathologic scores and oxidative parameters.

• The role of inducible nitric oxide synthase inhibitor, meropenem, and taurine in experimental acute necrotizing pancreatitis.

  Authors: Mustafa Ozturk, Mehmet Refik Mas, Mehmet Yasar, Cemal Akay, Hakan Aydogan, Salih Deveci, Bilgin Comert, Ismail Simsek, Nuket Mas, Ismail Hakki Kocar

  Pancreas. 06/2003; 26(4):357-62.

  INTRODUCTION: Translocation of bacteria from the gut is one of the most important factors in the development of septic complications and mortality in acute pancreatitis. AIMS: To investigate whetherINTRODUCTION: Translocation of bacteria from the gut is one of the most important factors in the development of septic complications and mortality in acute pancreatitis. AIMS: To investigate whether S-methylisothiourea (SMT), taurine (TAU), and meropenem (MER) could effect bacterial translocation and the course of acute necrotizing pancreatitis. METHODOLOGY: Seventy male Sprague-Dawley rats were studied. Rats were randomly allocated into seven groups. Acute pancreatitis was induced in group II (MER), group III (TAU), group IV (TAU + MER), group V (TAU + SMT), group VI (TAU + MER + SMT), and group VII (positive control) by retrograde injection of taurocholate into the common biliopancreatic duct. Group I rats (sham) received normal saline infusion into the common biliopancreatic duct as negative control. Rats were treated with drug combinations intraperitoneally for 48 hours after induction of pancreatitis. At the 48th hour of induction, all animals were killed, and specimens were collected. RESULTS: Bacterial translocation to peritoneum and pancreas in groups treated with MER were lower than in the other groups. Pancreatic tissue GSHpx and SOD levels were higher in all groups in comparison with levels in group VII. Pancreatic tissue MDA levels were also lower in all treatment groups except group II. The most favorable results were obtained in group VI (TAU + MER + SMT). Also, the lowest pathologic score between the groups in which acute pancreatitis developed was obtained in group VI. CONCLUSIONS: Addition of TAU and SMT to the treatment protocol for acute pancreatitis seems to improve the pathologic score and oxidative stress parameters. Also, antibiotherapy with MER decreases the risk of bacterial translocation.

• The use of lower turbinate bone grafts in the treatment of saddle nose deformities.

  Authors: Ali Gurlek, Ibrahim Askar, Bilge T Bilen, Hakan Aydogan, Alpay Fariz, Nezih Alaybeyoglu

  Aesthetic plastic surgery. 26(6):407-12.

  Saddle nose reconstruction is based on the use of support grafts to manage aesthetic and functional problems. Bone (calvarial, iliac crest, costal, nasal hump, ulnar, and heterogeneous origin),Saddle nose reconstruction is based on the use of support grafts to manage aesthetic and functional problems. Bone (calvarial, iliac crest, costal, nasal hump, ulnar, and heterogeneous origin), cartilage (septal, costal, heterogeneous), and synthetic materials (silicon, silastic, polyethylene) were used as support grafts. Three patients have been included in this study to define the surgical management and long-term aesthetic and functional results of patients undergoing rhinoplasty with support grafts for a saddle nose deformity. Open rhinoplasty was employed. Both the lower turbinates were excised and the bone dissected from the soft tissues in two cases and in one case, only mucosa was removed. The amount of support needed was measured by using bone wax. The bone was used shaped in layers, according to the defect, and sutured to each other by vycril suture, and wrapped around by surgicell. The graft was then inserted in its place and fixed with external prolene sutures. Results were satisfactory in both function and aesthetics. Ten to 16-month follow-ups had no complications. Saddle nose surgery basically requires the use of a support graft to repair the nasal dorsum. A lower turbinate bone graft procedure has some advantages: it is cheap and safe, it is ready to use and not time-consuming, there is no donor area and no additional donor site morbidity, and it enlarges the airway and the passage to prevent nasal airway obstruction.

• Effects of different corticosteroids on edema and ecchymosis in open rhinoplasty.

  Authors: Ali Gurlek, Alpay Fariz, Hakan Aydogan, Ayse Ersoz-Ozturk, Ahmet T Eren

  Aesthetic plastic surgery. 30(2):150-4.

  A double-blind, randomized trial with placebo control was planned to evaluate the effects of corticosteroids (betamethasone, dexamethasone, methylprednisolone) in approximately equivalent doses (8 mgA double-blind, randomized trial with placebo control was planned to evaluate the effects of corticosteroids (betamethasone, dexamethasone, methylprednisolone) in approximately equivalent doses (8 mg dexamethasone/day), and to compare their effects with that of tenoxicam, an antiinflammatory drug, on both the edema and ecchymosis in open rhinoplasty with osteotomies. For this study, 40 patients were divided randomly into five groups of 8 patients each, which received, respectively, betamethasone (group 1), dexamethasone (group 2), methylprednisolone (group 3), tenoxicam (group 4), and placebo (group 5). Open rhinoplasty with osteotomies was performed by the same surgeon with the patient under general anesthesia. Drugs were administered just before the induction of anesthesia and continued for 3 days. Only acetaminophen was used to control postoperative analgesia. Digital photographs of each patient were taken on postoperative days 1, 3, and 7. Scoring was performed separately for eyelid swelling and ecchymosis by three observers independently using a graded scale from 0 to 4. No statistically significant differences existed among the five groups in terms of age, sex, duration of surgery, amount of bleeding, and intravenous fluid administration during the surgery. On postoperative days 1, 3, and 7, no differences in the levels of ecchymosis or edema among the steroid groups, the tenoxicam group, and the control groups were observed. In conclusion, the authors observed no significant differences among the different kinds of steroids administered in equivalent doses (8 mg dexamethasone/day). Steroids used in these doses were not effective in preventing or reducing edema and ecchymosis after open rhinoplasty with osteotomies. Tenoxicam also was not effective. No complications caused by the use of steroids were observed during the 6-month follow-up period.

• Correction of the crooked nose using custom-made high-density porous polyethylene extended spreader grafts.

  Authors: Ali Gürlek, Ayse Ersoz-Ozturk, Mehmet Celik, Cemal Firat, Serkan Aslan, Hakan Aydogan

  Aesthetic plastic surgery. 30(2):141-9.

  Correction of the crooked or deviated nose, a complex cosmetic and functional problem, is a big challenge for the rhinoplasty surgeon. Although corrections using a wide range of surgical techniquesCorrection of the crooked or deviated nose, a complex cosmetic and functional problem, is a big challenge for the rhinoplasty surgeon. Although corrections using a wide range of surgical techniques to straighten the nose and maximize nasal function have been proposed, recurrence is very common because of cartilage memory and scar contracture. Therefore, to prevent recurrence and to maintain the correction of the septum, a permanent support that is stable and strong, with the ability to maintain its given shape after placement on one or both sides of the septum, is needed. For this purpose, the authors planned to use a pair of custom-made high-density porous polyethylene (HDPP) extended spreader grafts. In this study, the concept and technique of HDPP, composed of a nonresorbable alloplastic material for correction of the crooked nose, and the authors' experience using it, are presented. Currently, HDPP is readily available on the market as a thin plain sheet (0.85 x 38 x 50 mm) that can be cut to an appropriate size for spreader grafts. Ingrowths of fibrous tissue inside and around HDPP stabilize the upper lateral cartilages and septum in their new corrected position and maintain the corrected/straightened position. This material was used in 20 patients with crooked noses (9 with C-type and 11 with S-type noses). During a mean follow-up period of 18 months (range, 8-30 months), there were no complications, recurrences, or extrusions. Functional evaluation was performed using a visual analog scale before surgery and 6 months after surgery. Patients were asked to score their nasal breathing on a scale ranging from 0 to 100. The mean preoperative value was 32.50% +/- 11.18%, and the postoperative value was 88.75% +/- 8.71%. In conclusion, the use of custom-made HDPP extended spreader grafts is a safe, effective, reliable, and permanent method for correction of the crooked nose. In the long term, the authors believe that custom-made HDPP extended spreader grafts provide functional recovery and increased strength against further trauma or forces of scar contracture, and have the ability to prevent recurrence attributable to cartilage memory.