Roberto Meyer

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Verified

Roberto verified their affiliation via an institutional email.

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• PhD, Full Professor
• Professor (Full) at Federal University of Bahia

Multiple Myeloma (MM) is a cytogenetically heterogeneous clonal plasma cell proliferative disease whose diagnosis is supported by analyses on histological slides of bone marrow aspirate. In summary, experts use a labor-intensive methodology to compute the ratio between plasma cells and non-plasma cells. Therefore, the key aspect of the methodology...

Caseous lymphadenitis can be diagnosed using serological tests, mainly the enzyme-linked immunosorbent assay (ELISA). In this work, we evaluated interferon-gamma production in goats infected and not infected with Corynebacterium pseudotuberculosis, correlating it with the ELISA diagnostic test and analyzing the cellular and humoral responses, respe...

A caprinocultura é um importante segmento no agronegócio. Porém, existem alguns entraves na produção que causam graves prejuízos, dentre eles, patógenos responsáveis por doenças persistentes, o C. pseudotuberculosis - agente etiológico da linfadenite caseosa. Para analisar a infecção da doença, 18 (dezoito) caprinos da raça Canindé foram divididos...

Introduction: Corynebacterium pseudotuberculosis is an intracellular facultative bacterium that affects macrophages, causing caseous lymphadenitis in goats and sheep. This disease is characterised by the formation of granulomas and results in significant economic losses for farmers of goats and sheep around the world. Phagosome maturation is essent...

The pathogenesis of acute myeloid leukemia (AML) involves mutations in genes such as FLT3 and NPM1 , which are also associated with the prognosis of the disease. The immune system influences disease progression, but the mechanisms underlying the interaction between the immune system and AML are not clear. In this study, the profiles of lymphocytes...

The pandemic caused by the SARS-CoV-2 virus has represented a global challenge with a significant impact on public health since its emergence in 2019. Understanding the interactions between this virus and the human immune system is essential for the development of new strategies more effective therapies and diagnoses. This study aimed to predict ep...

Multiple Myeloma (MM) is a hematological malignancy characterized by the clonal proliferation of plasma cells within the bone marrow. Diagnosing MM presents considerable challenges, involving the identification of plasma cells in cytology examinations on hematological slides. At present, this is still a time-consuming manual task and has high labor...

A linfadenite caseosa (LC), cujo agente Corynebacterium pseudotuberculosis é o responsável por desenvolver um processo infeccioso em ovino e caprinos, com consequentes perdas econômicas a cadeia produtiva. Os estados do Nordeste assumem o maior número de casos de prevalência, em virtude de concentrar os maiores rebanhos de pequenos ruminantes do pa...

Corynebacterium pseudotuberculosis is a gram-positive bacterium and is the etiologic agent of caseous lymphadenitis (CL) in small ruminants. This disease is characterized by the development of encapsulated granulomas in visceral and superficial lymph nodes, and its clinical treatment is refractory to antibiotic therapy. An important virulence facto...

There are few reports of Trypanosoma in snakes, as well as little information about its pathogenicity in these animals. Thus, the present study aimed to characterize Trypanosoma found in Boa constrictor snakes, to verify the influence of the parasitism on hematological and clinical biochemistry parameters, and to perform a phylogenetic study of the...

Following the COVID-19 pandemic, it's crucial to understand the relationship between immune responses and clinical results, which also underpins interdisciplinary educational discussions. This study goes beyond standard medical evaluation, linking clinical medicine to sociodemography, genetics, and education, emphasizing the importance of an interc...

Background: The growing contact between men and wild animals, caused by the increase in the population in urban centers and the destruction of the habitat of these animals, has been leading to a greater circulation of pathogens between humans and wildlife. Chelonoidis carbonaria, a tortoise found throughout South America, is one of the animals most...

The aim of the study was to evaluate the association between salivary anti-Porphyromonas gingivalis IgA antibodies and the leprosy reaction. The levels of salivary anti - P. gingivalis IgA antibodies, together with salivary flow and pH were measured in individuals diagnosed with leprosy and associated with the development of the leprosy reaction. S...

Identifying individuals and factors associated with severe cases of COVID-19 is crucial as the pandemic continues to spread globally. Effective biomarkers for predicting severe cases are essential for optimizing clinical management, therapy, and preventing unfavorable outcomes. This exploratory observational study aimed to investigate the expressio...

10621 Background: The identification of BRCA1 and BRCA2 genes mutations are of paramount importance in the treatment and follow-up of hereditary cancer patients. When a pathogenic variant (PV) is identified in one of these genes, the surveillance for new primary tumors becomes individualized. When a pathogenic mutation is identified other family me...

Caseous lymphadenitis (CLA), an infectious disease caused by Corynebacterium pseudotuberculosis in small ruminants, is highly prevalent worldwide. Economic losses have already been associated with the disease, and little is known about the host–pathogen relationship associated with the disease. The present study aimed to perform a metabolomic study...

Background and Aims: Hepatitis Delta virus (HDV) genotype 3 is responsible for outbreaks of fulminant hepatitis in Northeastern South America. This study investigates if systemic inflammatory molecules are differentially expressed in patients with advanced fibrosis chronically infected with Hepatitis Delta virusgenotype 3(HDV-3). Methods: Sixty-one...

Dental cements are widely used in the clinical routine, specifically for root canal sealing. Within this context, it is expected that these materials present antimicrobial activity, since it would help in the prevention of apical and periapical infections. The present study aimed to comparatively verify the antimicrobial activity of four dental cem...

Candida haemulonii is an emergent infectious pathogen that affects human presenting comorbidities and/or immunodepression. Little is known about other possible hosts. For the first time, this fungus was found causing a cutaneous infection in a snake, Boa constrictor, characterized by scale opacity and several ulcerative lesions. This C. haemulonii...

Background: The high structural similarity between the Zika virus (ZIKV) and other flaviviruses, such as Dengue Virus (DENV), complicates the identification of the infecting virus due to the occurrence of cross-reactions in serological assays. This phenomenon has increased the demand for more specific antigens for immunodiagnostic applications. M...

Introduction and Objectives: Hepatitis E is an infection caused by the E virus (HEV) with the fecal-oral transmission. The spectrum of the disease varies from acute form to chronic evolution. There are few studies in the rural region of Bahia State. This study aimed to study the seroprevalence of hepatitis E in a city in a rural region in Brazil. M...

Background: Candida spp. is the main fungal genus related to infections in humans, and its treatment has become a challenge due to the production of biofilm and its resistance/multi-resistance profile to conventional antifungals. Antimicrobial photodynamic therapy stands out as a treatment characterized by a broad spectrum of antimicrobial action,...

Staphylococcal A and streptococcal G proteins are widely used in immunoassays when specific immunological reagents are unavailable, such as for wild animals. The affinity of bacterial proteins A and G to the immunoglobulins of seven Brazilian mammals were tested, including black-tufted marmoset (Callithrix penicillata, n = 5), golden-bellied capuch...

Introduction: Hepatitis E virus infection can lead to severe liver disease and unregulated hepatitis in patients with a history of previous chronic liver disease of different etiologies. Objective: To determine the seroprevalence of hepatitis E in untreated carriers of hepatitis C virus, hepatitis B virus, autoimmune hepatitis and in patients with...

Caseous lymphadenitis (CLA), an infectious disease caused by Corynebacterium pseudotuberculosis in goats and sheep, is highly prevalent worldwide and is characterized by economic losses in small ruminant production. Currently available techniques for clinical and laboratory diagnosis of the disease lack market availability and/or sensitivity, and t...

Human adipose tissue-derived stem cells (hASC) secretome display various therapeutically relevant effects in regenerative medicine, such as induction of angiogenesis and tissue repair. The benefits of hASC secretome are primarily orchestrated by trophic factors that mediate autocrine and paracrine effects in host cells. However, the composition and...

Objective: To characterize the immunophenotypic profile of acute leukemias in the population of the state of Bahia, Brazil. Methods: This is a descriptive, retrospective study. From 2014 to 2018, 796 new cases of acute leukemia were evaluated. The data were obtained from analysis of reports and records of tests performed by flow cytometry immuno...

Caseous lymphadenitis (CLA) is a disease that affects small ruminants, and the best way to prevent its spread on a herd is through immunoprophylaxis. Thus, we aimed to evaluate the MBP:PLD:CP40 fusion protein as a new CLA immunogen. The fusion protein was constructed by combining Corynebacterium pseudotuberculosis PLD and CP40 proteins with maltose...

Corynebacterium pseudotuberculosis é o agente causador da linfadenite caseosa (LC), uma doença infecciosa, granulomatosa, crônica e debilitante que acomete diversos animais, entre eles, caprinos, ovinos, bovinos, equinos, camelídeos e, mais raramente, seres humanos. O grupo denominado CMNR, composto por bactérias dos gêneros Corynebacterium, Mycoba...

The P22 ELISA was recently developed for the serodiagnosis of animal tuberculosis. Herein, the stability of the P22 antigen in different presentations and storage conditions, and the cross-reactivity with Corynebacterium pseudotuberculosis infection in small ruminants were evaluated. For the stability assay, serum samples from cows, sheep, goats, a...

The aim of the study was to evaluate the association between salivary anti- Porphyromonas gingivalis IgA antibodies and the leprosy reaction. The levels of salivary anti - P. gingivalis IgA antibodies, together with salivary flow and pH were measured in individuals diagnosed with leprosy and associated with the development of the leprosy reaction....

Corynebacterium pseudotuberculosis é o agente etiológico da linfadenite caseosa (LC), uma doença infecciosa crônica que afeta ovinos e caprinos. Numerosos testes sorológicos foram desenvolvidos para detectar a doença, sendo o Ensaio Imunoenzimático (ELISA) um dos mais utilizados devido às suas vantagens de sensibilidade e especificidade. O presente...

Corynebacterium pseudotuberculosis is a bacillus that causes caseous lymphadenitis in small ruminants, leading to great losses to rural producers; thus, an efficient diagnosis is necessary for using disease control measures. This study aimed to evaluate the antigenic potential of four C. pseudotuberculosis recombinant proteins (rSodC, rPknG, rNanH,...

In this study, we investigated the capacity of the recombinant proteins SpaC, NanH, SodC, and PLD of C. pseudotuberculosis to trigger protective humoral and cellular immune responses against experimentally induced C. pseudotuberculosis infection in sheep. The antigens were produced in a heterologous system and were purified by affinity chromatograp...

A linfadenite caseosa, é uma doença crônica infecciosa de pequenos ruminantes, caprinos e ovinos, causadora de grandes perdas econômicas, caracterizada pela formação de granulomas subcutâneosz e em órgãos internos cujo agente etiológico é Corynebacterium pseudotuberculosis, bacilo Gram-positivo, patógeno intracelular facultativo de fagócitos, relac...

Background l-Glutamine (l-GLN) is the most abundant amino acid in the human body. In hypercatabolic conditions, supplementation with l-GLN improves immunological function. Among the immune cells, the lymphocytes are the largest consumers of l-GLN in a catabolic disease state. Here, we evaluated the efect of l-GLN treatment on the expression of T an...

Corynebacterium pseudotuberculosis é o agente causador da linfadenite caseosa dos caprinos e ovinos, enfermidade associada a perdas econômicas diretas no setor pecuário. Além de ter um curso crônico, o seu tratamento com antibióticos é inviável e não existem vacinas eficazes disponíveis no mercado. Neste experimento, foram utilizadas condições de c...

Introduction: The therapy with radioisotopes is widely used, its beginnings were focused on thyroid pathologies treatments. Over the years, the radiopharmaceuticals and/or radioisotopes have had their usage increased, to be used on painful bone metastasis. Material and Methods: A bibliographic search was conducted in the major health Science basis...

Purpose There is a paucity of data on the spectrum and prevalence of pathogenic variants among women of African ancestry in the Northeast region of Brazil. Methods We performed BROCA panel sequencing to identify inherited loss-of-function variants in breast cancer susceptibility genes among 292 Brazilian women referred to a single institution canc...

e22522 Background: The Oncogenetics service at the Federal University of Bahia was implemented in 2007 and since then has been offering pre- and post-test genetic counseling for cancer susceptibility genes, mainly tumors associated with King's syndrome in the population of the state of Bahia. This is a mixed population of about 80% of African ances...

Viral hepatitis are still considered as public health problems. Hepatitis caused by HAV and HEV, spread by enteric transmission are, acute infections associated with precarious basic sanitation, inappropriate hygiene and consumption of contaminated food. Hepatitis caused by HBV and HCV viruses transmitted by parenteral /sexual route are associated...

Corynebacterium pseudotuberculosis is the etiological agent of caseous lymphadenitis. The main clinical sign of this disease is the development of granulomas, especially in small ruminants; however, the pathways that are involved in the formation and maintenance of these granulomas are unknown. Cytokines and chemokines are responsible for the migra...

Candida spp. resistant to commercially available antifungals are often isolated from patients with oral candidiasis, a situation that points to the need for the development of new therapies. Thus, we evaluated the activity of Fusarium oxysporum-based silver nanoparticles (AgNPs) on Candida spp. isolated from denture stomatitis lesions. Candida isol...

Corynebacterium pseudotuberculosis is a facultative intracellular pathogen that uses various mechanisms to survive within macrophages. In phagocytosis, this survival can be attributed to the ability to inhibit phagosome-lysosome fusion. In this fusion, some proteins, including Rabs GTPases, are involved in the maturation process and are responsible...

Caseous Lymphadenitis (CLA) is a chronic disease that affects also small ruminants. CLA is caused by Corynebacterium pseudotuberculosis and is responsible for high economic losses due to the formation of superficial and visceral granulomas, the latter is considered as asymptomatic CLA causing high levels of dissemination. Several vaccination strate...

Background Oral candidiasis is an opportunistic disease caused by fungi of the Candida genus. The occurrence of Candida spp. resistance to the commercial antifungal drugs points to the search for alternative treatments. Propolis has been successfully used in the treatment of infectious diseases for centuries. It has been proposed that an ultrasound...

Purpose: There is a paucity of data on the spectrum and prevalence of pathogenic variants among women of African ancestry in the Northeast region of Brazil. Methods: We performed BROCA panel sequencing to identify inherited loss-of-function variants in breast cancer susceptibility genes among 292 Brazilian women referred to a single institution can...

SARS-COV-2 is the virus responsible for COVID-19 being declared a pandemic in March 2020 by the World Health Organization due the rapid spread representing a global health crisis. The disease is characterized by a wide clinical spectrum ranging from asymptomatic forms until severe viral pneumonia, which can to evolve to severe acute respiratory syn...

The production of small ruminants is an important economic activity of the brazilian Northeast, but some diseases have a high prevalence in this region, such as caseous lymphadenitis (CL), caused by Corynebacterium pseudotuberculosis. The treatment of CL is often ineffective, which justifies the search of new active principles from plants, mainly o...

Corynebacterium pseudotuberculosis is the etiological agent of caseous lymphadenitis in small ruminants, a chronic disease characterized by the development of granulomas in superficial and visceral lymph nodes as well as in several organs. An important characteristic of the infection with this bacterium is the formation of a biofilm and the absence...

Introduction Hepatitis A virus (HAV) is a hepatotrophic virus of fecal-oral transmission. Occupational exposure in the health area is not considered a risk of HAV contagion. Adults are more likely to develop fulminant hepatitis. In Brazil, those over 20 years of age have a high prevalence of anti-HAV antibodies (IgGHAV). Objective To study the pre...

Recombinant proteins are generally fused with solubility enhancer tags to improve the folding and solubility of the target protein of interest. However, the fusion protein strategy usually requires expensive proteases to perform in vitro proteolysis and additional chromatographic steps to obtain tag‐free recombinant proteins. Expression systems bas...

The COVID-19 pandemic, originating in China, has spread across the world, with serious proportions in populations and public health. Systemic lesions in those infected generate cascading changes affecting different organs. Osteonecrosis is a bone pathology, of different etiologies, common throughout the world, which directs the hip to a disabling c...

Corynebacterium pseudotuberculosis, a facultative intracellular pathogen, causes caseous lymphadenitis, a disease of veterinary importance in small ruminants. In order to reduce the economic losses caused by the disease, an effective prophylactic measure is necessary. We adopted an immunoinformatic approach to evaluate the immunological profile of...

Lipophosphoglycan (LPG), when used as an ELISA target, confers high specificity and sensitivity to the detection of Leishmania infantum antibodies in dogs. Glycoconjugates are economically viable because the yield is very high after extraction/purification. In addition, they are very stable, which allows their use in point-of-care testing without s...

TLL is a malignant and aggressive leukemia whose survival time is limited. It is known that 5% of individuals infected with HTLV-1, after many years of latency, may develop this disease. The mechanisms by which the evolution of clinical conditions occurs are unknown, and in Brazil there are few studies about ATLL, this some important themes will be...

Recombinant proteins are generally fused with solubility enhancer tags to improve target protein folding and solubility. However, the fusion protein strategy usually requires the use of expensive proteases to perform in vitro proteolysis and additional chromatography steps to obtain tag-free recombinant proteins. Expression systems based on intrace...

Caseous lymphadenitis (CLA) is a chronic disease that affects small ruminants and causes economic losses in the associated breeding system. The causative agent of CLA is Corynebacterium pseudotuberculosis, a Gram-positive bacterium that exhibits tropism for external and internal lymph nodes and induces abscess formation in the host. Bacterial commu...

ATLL is a malignant and aggressive leukemia whose survival time is limited. It is known that 5% of individuals infected with HTLV-1, after many years of latency, may develop this disease. The mechanisms by which the evolution of clinical conditions occurs are unknown, and in Brazil there are few studies about ATLL, this some important themes will b...

Introduction: Hepatitis A Virus (HAV) is a hepatotrophic virus with oral-fecal transmission. Occupational exposition to the virus is not common in the health practice and this way of contagious is not considered as a risk of infection. Adults have more probability to have fulminate clinical manifestations and in Brazil, the most of population older...

The genus Klebsiella comprises species that cause nosocomial and community-acquired infections. A dataset was created to compile the sequence type (ST) and capsule type (K-locus) information predicted for 172 worldwide isolates of Klebsiella spp. whose complete genomes could be retrieved from the GenBank (NCBI) repository. The dataset also includes...

p> Introdução: Este estudo trata do controle de qualidade do radiofármaco utilizado em estudos de PET-CT para diagnóstico e/ou estadiamento de pacientes acometidos pelo câncer de próstata. Objetivo: Avaliar a qualidade do radiofármaco PSMA-11, marcado com uso de gerador de Ge⁶⁸-Ga⁶⁸ itinerante. Método: Análise do aspecto visua...

Despite the economic and zoonotic relevance of caseous lymphadenitis, a competent immunoprophylaxis tool is still necessary. Here, we evaluated two putative virulence factors of Corynebacterium pseudotuberculosis, rNanH, and rPknG, as recombinant subunit vaccines in a murine model against the infection by C. pseudotuberculosis. Three groups of ten...

The emergence of community acquired infections increases the public health concern on K. pneumoniae and closely related bacteria among which antimicrobial resistance spreads. We report a multidrug-resistant K. pneumoniae isolate, B31, of a patient infected in the community and admitted to an intensive care unit in Northeast Brazil. Antimicrobial su...

The potential use of bone marrow mesenchymal stromal cells (BM-MSCs) for the treatment of osteonecrosis in sickle cell disease (SCD) patients is increasing. However, convenient BM-MSC quantification and functional property assays are critical factors for cell-based therapies yet to be optimized. This study was designed to quantify the MSC populatio...

The Antillean manatee (Trichechus manatus manatus) can be found along the Brazilian northern and northeastern coasts. Previous studies on the clinical biochemistry of these animals were conducted in North America and the Caribbean, whereas little is known regarding these parameters in South American manatee populations. Accordingly, the objective o...

Caseous lymphadenitis (CL) is a chronic infectious disease that affects sheep and goats. Many serological tests have been developed to detect the disease; one of the most widely used is the enzyme-linked immunosorbent assay (ELISA), due to its advantages, which include acceptable cost-effectiveness, applicability, sensitivity and specificity. ELISA...

Recent evidence suggests that abnormalities involving CD4+T lymphocytes are associated with the pathophysiology of osteonecrosis (ON); however, few studies have addressed the CD4+T cells in ON related to sickle cell disease (SCD/ON). In addition, T cells producing multiple cytokines simultaneously are often present in the inflammatory milieu and ma...

Objective To determine the association between the presence of periodontal pathogens and low birthweight. Methods This observational and case-control study consisted of mothers of infants weighing <2,500g (Group A), and mothers of newborns weighing ≥2,500g (Group B), born at Hospital da Mulher in Feira de Santana (BA), Brazil. A semi-structured qu...

Caseous lymphadenitis (CL) is a chronic infectious disease that affects sheep and goats. Many serological tests have been developed to detect the disease; one of the most widely used is the enzyme-linked immunosorbent assay (ELISA), due to its advantages. ELISA formulations using recombinant proteins can exhibit significant sensitivity and specific...

Caseous lymphadenitis (CL) is a chronic infectious disease that affects sheep and goats. Many serological tests have been developed to detect the disease; one of the most widely used is the enzyme-linked immunosorbent assay (ELISA), due to its advantages. ELISA formulations using recombinant proteins can exhibit significant sensitivity and specific...

Caseous lymphadenitis (CL) is a chronic infectious disease that affects sheep and goats. Many serological tests have been developed to detect the disease; one of the most widely used is the enzyme-linked immunosorbent assay (ELISA), due to its advantages, which include acceptable cost-effectiveness, applicability, sensitivity and specificity. ELISA...

Caseous lymphadenitis (CL) is a chronic infectious disease that affects sheep and goats. Many serological tests have been developed to detect the disease; one of the most widely used is the enzyme-linked immunosorbent assay (ELISA), due to its advantages. ELISA formulations using recombinant proteins can exhibit significant sensitivity and specific...

Caseous lymphadenitis (CLA) is an infectious disease caused by Corynebacterium pseudotuberculosis in small ruminants and is characterized by the development of granulomas in the lymph nodes, spleen, liver, and lungs. Although little is known about the host-pathogen relationship of this bacterium, it was previously reported that the pathogen’s lipid...

Leptospirosis, a disease that occurs worldwide, especially in tropical regions, is caused by bacteria of the genus Leptospira and affects mammals, amphibians, and reptiles. Boa constrictor snakes are commonly found in Atlantic rainforest fragments in peri-urban areas, which indicates a greater possibility of the contact of these animals with humans...

The Ixodidae family comprises ticks that are hematophagous ectoparasites and are considered vectors of several hemoparasites from the Anaplasmataceae family and the genus Hepatozoon, Babesia, and Rickettsia. These ectoparasites parasitize domestic and wild animals belonging to several vertebrate groups. Ticks are highly adapted to different biomes...

A resistência do Rhipicephalus (Boophilus) microplus a acaricidas é uma preocupação. Avaliamos uma população isolada do semi-árido brasileiro durante um período de cinco anos. Variações significativas na eficácia dos acaricidas estudados foram correlacionadas com padrões históricos de uso, que variaram significativamente ao longo do período.

Blood typing techniques have been improved to ensure greater safety for transfusion procedures. Typification for the DEA 1 antigen through flow cytometry should offer more reliability to routine immunohematology in donor and recipient dogs. Currently, the DEA 1 group is starting to be an autosomal dominant allelic system with the DEA 1 negative typ...

Introduction: Periodontitis is a multifactorial disease, characterized by an inflammatory response of the periodontal tissues to a dysbiotic biofilm in the subgingival surface. The presence of keystone pathogens, such as Porphyromonas gingivalis, is one of the main causes of dysbiosis, although the host response is preponderant in the beginning and...

Clinical mycoses treatment is associated with issues such as negative side effects, high cost, prolonged treatment, and resistant strain selection. Malassezia pachydermatis is the most frequently isolated yeast in cases of canine otitis and dermatitis. The number of fungal strains exhibiting primary resistance to several drugs in vitro is increasin...