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1.
J Vis Exp ; (192)2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36912517

RESUMO

Mycoplasma pneumoniae is a cell wall-deficient prokaryote, mainly known to colonize the human respiratory tract and to be endemic, with epidemic peaks every 6 years, in older children and young adults. Diagnosis of M. pneumoniae is challenging because of the fastidious nature of the pathogen and the possibility of asymptomatic carriage. Laboratory diagnosis of M. pneumoniae infection based on antibody titration in the serum samples of patients remains the most practiced method. Because of the potential problem of immunological cross-reactivity with the use of polyclonal serum for M. pneumoniae, an antigen-capture enzyme-linked immunosorbent assay (ELISA) has been developed to improve the specificity of serological diagnosis. ELISA plates are coated with M. pneumoniae polyclonal antibodies, raised in rabbits and rendered specific after adsorption against a panel of heterologous bacteria that share antigens with M. pneumoniae species and/or are known to colonize the respiratory tract. The reacted M. pneumoniae homologous antigens are then specifically recognized by their corresponding antibodies in the serum samples. Further optimization of the physicochemical parameters to which the antigen-capture ELISA is subjected led to a highly specific, sensitive, and reproducible ELISA.


Assuntos
Anticorpos Antibacterianos , Mycoplasma pneumoniae , Criança , Animais , Humanos , Coelhos , Anticorpos Antibacterianos/análise , Ensaio de Imunoadsorção Enzimática/métodos , Antígenos de Bactérias , Imunoglobulina M
2.
Microorganisms ; 10(7)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35889084

RESUMO

Antimicrobial resistance (AMR) studies of Mycoplasma bovis have generally focused on specific loci versus using a genome-wide association study (GWAS) approach. A GWAS approach, using two different models, was applied to 194 Mycoplasma bovis genomes. Both a fixed effects linear model (FEM) and a linear mixed model (LMM) identified associations between nucleotide variants (NVs) and antimicrobial susceptibility testing (AST) phenotypes. The AMR phenotypes represented fluoroquinolones, tetracyclines, phenicols, and macrolides. Both models identified known and novel NVs associated (Bonferroni adjusted p < 0.05) with AMR. Fluoroquinolone resistance was associated with multiple NVs, including previously identified mutations in gyrA and parC. NVs in the 30S ribosomal protein 16S were associated with tetracycline resistance, whereas NVs in 5S rRNA, 23S rRNA, and 50S ribosomal proteins were associated with phenicol and macrolide resistance. For all antimicrobial classes, resistance was associated with NVs in genes coding for ABC transporters and other membrane proteins, tRNA-ligases, peptidases, and transposases, suggesting a NV-based multifactorial model of AMR in M. bovis. This study was the largest collection of North American M. bovis isolates used with a GWAS for the sole purpose of identifying novel and non-antimicrobial-target NVs associated with AMR.

3.
Saudi Med J ; 43(7): 755-759, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35830998

RESUMO

OBJECTIVES: To determine the prevalence and characterize prostate cancer (PC) cases in Aseer, Saudi Arabia. METHODS: This study involved 883 patients who consulted physicians in Aseer Central Hospital, Abha, Saudi Arabia, for prostate issues between the years 2008-2018. All patients underwent digital rectal examination and measurement of their serum prostate-specific antigen levels. For patients who presented abnormal digital rectal examination findings and elevated prostate-specific antigen levels, prostate biopsies were recommended. Specimens were histopathologically examined to differentiate between malignant and benign tumors. RESULTS: Among the 883 included patients, 132 (15%) underwent a prostate biopsy and were found to have a tumor. Histopathological examination confirmed malignancy (PC) in 77 (8.7%) patients. The absolute majority of the patients diagnosed with PC (96%) were aged >60 years and almost all of them (92%) were found to have a high prostate-specific antigen level of >4 ng/ml. CONCLUSION: Prostate cancer appears to be a serious disease in Aseer, Saudi Arabia. Further studies aimed at determining the causes of this type of cancer and understanding its mechanisms are warranted.


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Biópsia , Humanos , Masculino , Prevalência , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/epidemiologia , Arábia Saudita/epidemiologia
4.
J Oncol ; 2021: 9986550, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34373693

RESUMO

More than one million new cancer cases occur worldwide every year. Although many clinical trials are applied and recent diagnostic tools are employed, curing cancer disease is still a great challenge for mankind. Heredity and epigenetics are the main risk factors often related to cancer. Although, the infectious etiological role in carcinogenesis was also theorized. By establishing chronic infection and inflammation in their hosts, several microorganisms were suggested to cause cell transformation. Of these suspicious microorganisms, mycoplasmas were well regarded because of their intimate parasitism with host cells, as well as their silent and insidious role during infections. This assumption has opened many questions about the real role played by mycoplasmas in oncogenesis. Herein, we presented a sum up of many studies among the hundreds which had addressed the Mycoplasma-cancer topic over the past 50 years. Research studies in this field have first started by approving the mycoplasmas malignancy potential. Indeed, using animal models and in vitro experiments in various cell lines from human and other mammalians, many mycoplasmas were proven to cause varied modifications leading to cell transformation. Moreover, many studies have looked upon the Mycoplasma-cancer subject from an epidemiological point of view. Diverse techniques were used to assess the mycoplasmas prevalence in patients with cancer from different countries. Not less than 10 Mycoplasma species were detected in the context of at least 15 cancer types affecting the brain, the breast, the lymphatic system, and different organs in the genitourinary, respiratory, gastrointestinal, and urinary tracts. Based on these revelations, one should concede that detection of mycoplasmas often linked to ''wolf in sheep's clothing" is not a coincidence and might have a role in cancer. Thorough investigations are needed to better elucidate this role. This would have a substantial impact on the improvement of cancer diagnosis and its prevention.

5.
Infect Agent Cancer ; 16(1): 6, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472649

RESUMO

BACKGROUND: The etiology of prostate cancer (PCa) is multiple and complex. Among the causes recently cited are chronic infections engendered by microorganisms that often go unnoticed. A typical illustration of such a case is infection due to mollicutes bacteria. Generally known by their lurking nature, urogenital mollicutes are the most incriminated in PCa. This study was thus carried out in an attempt to establish the presence of these mollicutes by PCR in biopsies of confirmed PCa patients and to evaluate their prevalence. METHODS: A total of 105 Formalin-Fixed Paraffin-Embedded prostate tissues collected from 50 patients suffering from PCa and 55 with benign prostate hyperplasia were subjected to PCR amplification targeting species-specific genes of 5 urogenital mollicutes species, Mycoplasma genitalium, M. hominis, M. fermentans, Ureaplasma parvum, and U. urealyticum. PCR products were then sequenced to confirm species identification. Results significance was statistically assessed using Chi-square and Odds ratio tests. RESULTS: PCR amplification showed no positive results for M. genitalium, M. hominis, and M. fermentans in all tested patients. Strikingly, Ureaplasma spp. were detected among 30% (15/50) of PCa patients. Nucleotide sequencing further confirmed the identified ureaplasma species, which were distributed as follows: 7 individuals with only U. parvum, 5 with only U. urealyticum, and 3 co-infection cases. Association of the two ureaplasma species with PCa cases proved statistically significant (P < 0.05), and found to represent a risk factor. Of note, Ureaplasma spp. were mostly identified in patients aged 60 and above with prostatic specific antigen (PSA) level > 4 ng/ml and an invasive malignant prostate tumor (Gleason score 8-10). CONCLUSIONS: This study uncovered a significant association of Ureaplasma spp. with PCa arguing in favour of their potential involvement in this condition. Yet, this finding, though statistically supported, warrants a thorough investigation at a much larger scale.

6.
Genome Announc ; 4(3)2016 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-27313300

RESUMO

Mycoplasma meleagridis and Mycoplasma gallinarum are bacteria that affect birds, but little is known about the genetic basis of their interaction with chickens and other poultry. Here, we sequenced the genomes of M. meleagridis strain MM_26B8_IPT and M. gallinarum strain Mgn_IPT, both isolated from chickens showing respiratory symptoms, poor growth, reduction in hatchability, and loss of production.

7.
PLoS One ; 11(3): e0152171, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27010566

RESUMO

Mycoplasma meleagridis infection is widespread in turkeys, causing poor growth and feathering, airsacculitis, osteodystrophy, and reduction in hatchability. Like most mycoplasma species, M. meleagridis is characterized by its inability to synthesize purine and pyrimidine nucleotides de novo. Consistent with this intrinsic deficiency, we here report the cloning, expression, and characterization of a M. meleagridis gene sequence encoding a major surface nuclease, referred to as Mm19. Mm19 consists of a 1941-bp ORF encoding a 646-amino-acid polypeptide with a predicted molecular mass of 74,825 kDa. BLASTP analysis revealed a significant match with the catalytic/dimerization domain of type II restriction enzymes of the RE_AlwI superfamily. This finding is consistent with the genomic location of Mm19 sequence, which dispalys characteristics of a typical type II restriction-modification locus. Like intact M. meleagridis cells, the E. coli-expressed Mm19 fusion product was found to exhibit a nuclease activity against plasmid DNA, double-stranded DNA, single-stranded DNA, and RNA. The Mm19-associated nuclease activity was consistently enhanced with Mg2+ divalent cations, a hallmark of type II restriction enzymes. A rabbit hyperimmune antiserum raised against the bacterially expressed Mm19 strongly reacted with M. meleagridis intact cells and fully neutralized the surface-bound nuclease activity. Collectively, the results show that M. meleagridis expresses a strong surface-bound nuclease activity, which is the product of a single gene sequence that is related to the RE_AlwI superfamily of endonucleases.


Assuntos
Proteínas de Bactérias/metabolismo , Endonucleases/metabolismo , Mycoplasma meleagridis/metabolismo , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Escherichia coli/genética , Soros Imunes , Mycoplasma meleagridis/enzimologia , Coelhos
8.
Genome Announc ; 3(3)2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25999574

RESUMO

Mycoplasma meleagridis is a prominent turkey bacterial pathogen associated with airsacculitis and reproductive disorders. Notwithstanding the economic losses caused by M. meleagridis, its genome has still not been sequenced. For a better understanding of its genetic background and pathogenicity mechanisms, we sequenced the genome of M. meleagridis type strain ATCC 25294.

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