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1.
Int J Mol Sci ; 25(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338795

RESUMO

The protection of the neonate against pathogens depends largely on the antibodies transferred placentally from the mother; for this reason, maternal vaccination against emerging viruses, such as SARS-CoV-2, is of vital importance. Knowing some of the immunogenic factors that could alter the placental transfer of antibodies could aid in understanding the immune response and neonatal protection after maternal vaccination. In this study, we analyzed the efficiency of the placental transfer of binding and neutralizing antibodies, as well as some factors that could alter the passive immune response, such as the trimester of gestation at the time of immunization, the number of doses received by the mother and the type of vaccine. Binding IgG antibodies were detected by ELISA, and the detection of neutralizing antibodies was carried out using flow cytometry. Our results show efficient transfer rates (>1), which are higher when maternal vaccination occurs during the third trimester of gestation. Antibodies are detectable in mothers and their neonates after 12 months of maternal immunization, suggesting than the vaccination against COVID-19 before and during pregnancy in the Mexican population induces a lasting neutralizing response in mothers and their newborns.


Assuntos
Anticorpos Neutralizantes , COVID-19 , Recém-Nascido , Gravidez , Feminino , Humanos , Vacinas contra COVID-19 , SARS-CoV-2 , COVID-19/prevenção & controle , Placenta , Vacinação , Mães , Anticorpos Antivirais
2.
Life (Basel) ; 13(11)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-38004249

RESUMO

Coccidioidomycosis, caused by Coccidioides immitis and C. posadasii, causes significant morbidity and mortality, both in immunocompetent and immunocompromised people, mainly in endemic areas. The present work analyzed its epidemiology, diagnostic methods, and treatment by reviewing clinical cases published from 1950 to 2021. Fifty-nine articles were included, corresponding to 275 clinical cases. The results showed a higher incidence of coccidioidomycosis in the male gender than the female gender. The most affected age group was 31-40 years, and the most reported clinical presentation was disseminated with greater involvement in cutaneous and subcutaneous tissue, followed by the CNS, bone system, and peritoneum. The species most frequently reported was C. immitis. The most used treatment was azoles, followed by their combination with amphotericin B, monotherapy with amphotericin B, and alternative medicine. This work shows that epidemiological data outside the USA are still scarce. Serological tests are the preferred diagnostic method in daily medical practice, and cultures remain the gold standard. The treatment for coccidioidomycosis is ketoconazole and amphotericin B, individually or in combination.

3.
Microorganisms ; 11(11)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38004780

RESUMO

Brachybacterium conglomeratum, traditionally considered an environmental bacterium, has recently garnered attention for its potential involvement in human health. While prior research hinted at its pathogenic role in humans, our study aims to determine its prevalence and associations in diverse clinical contexts. We examined vaginal swabs from three distinct patient groups: patients with low-grade squamous intraepithelial lesions (LSIL), patients with cervicovaginal infections, and patients with a history of precancerous lesions undergoing follow-up. B. conglomeratum was present in all three patient groups, with the highest prevalence observed in the LSIL group. Statistically significant associations were primarily identified in the LSIL group, where B. conglomeratum was present in 60% of cases. Notably, the LSIL group exhibited coinfections with multiple high-risk oncogenotypes of human papillomavirus (HPV), suggesting potential synergistic effects, and understanding these microbial relationships and their influence on viral persistence, particularly with HPV, holds promise for mitigating HPV-related carcinogenesis. Furthermore, Gardnerella vaginalis and Atopobium vaginae were frequently detected in this group, along with Ureaplasma parvum as the predominant sexually transmitted bacterium. In all cases, B. conglomeratum was found in association with these microorganisms rather than as a sole pathogen. This coexistence underscores the intricate microbial interactions within cervicovaginal infections and precancerous lesions. This study marks the first report of B. conglomeratum prevalence in women with these clinical conditions.

4.
Pathogens ; 12(8)2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37623981

RESUMO

HIV-associated hemophagocytic lymphohistiocytosis (HLH) is mainly due to infections caused by viruses, fungi, and, to a lesser extent, bacteria, often with fatal results. Case presentation: A 15-year-old pediatric patient from another institution was admitted to our hospital with a fever of unknown origin (FUO). Clinical analysis and laboratory studies diagnosed HIV infection. The approach to an FUO in a patient with AIDS is much more complex due to the search for common etiologies and opportunistic infections. In this case, disseminated histoplasmosis, pulmonary tuberculosis, pneumocystosis, and ehrlichiosis were diagnosed, prompting an urgent and comprehensive approach to prevent mortality. Due to the multiple infections, HLH was triggered. An early intervention with trimethoprim (TMP)-sulfamethoxazole (SMX), liposomal amphotericin B, doxycycline, and quadruple antiphimic therapy to suppress infections, in conjunction with the early administration of HLH treatment, favored the survival of this patient.

5.
J Fungi (Basel) ; 9(4)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37108916

RESUMO

Dermatophytes are fungi included in the genera Trichophyton, Microsporum, Epidermophyton, Nannizzia, Paraphyton, Lophophyton, and Arthroderma. Molecular techniques have contributed to faster and more precise identification, allowing significant advances in phylogenetic studies. This work aimed to identify clinical isolates of dermatophytes through phenotypic (macro- and micromorphology and conidia size) and genotypic methods (sequences of ITS regions, genes of ß tubulin (BT2), and elongation factor α (Tef-1α)) and determine the phylogenetic relationships between isolates. Ninety-four dermatophyte isolates from Costa Rica, Guatemala, Honduras, Mexico, and the Dominican Republic were studied. The isolates presented macro- and micromorphology and conidia size described for the genera Trichophyton, Microsporum, and Epidermophyton. Genotypic analysis classified the isolates into the genera Trichophyton (63.8%), Nannizzia (25.5%), Arthroderma (9.6%), and Epidermophyton (1.1%). The most frequent species were T. rubrum (26 isolates, 27.6%), T. interdigitale (26 isolates, 27.6%), and N. incurvata (11 isolates, 11.7%), N. gypsea and A. otae (nine isolates, 9.6%), among others. The genotypic methods clarified the taxonomic status of closely related species. For instance, the ITS and BT2 markers of T. rubrum/T. violaceum did not differ but the Tef-1α gene did. On the other hand, the three markers differed in T. equinum/T. tonsurans. Therefore, the ITS, BT2, and Tef-1α genes are useful for typing in phylogenetic analyses of dermatophytes, with Tef-1α being the most informative locus. It should be noted that isolate MM-474 was identified as T. tonsurans when using ITS and Tef-1α, but when using BT2, it was identified as T. rubrum. On the other hand, no significant difference was found when comparing the methods for constructing phylogenies, as the topologies were similar.

6.
Transl Oncol ; 33: 101680, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37121177

RESUMO

Tumor cells grow in three-dimensional (3D) channels-like structures denoted as vasculogenic mimicry (VM), which provides a route for nutrients and oxygen acquisition. VM is activated by hypoxia and associated with metastasis and poor prognosis. MetastamiRs are microRNAs regulating metastasis, however, if they control VM in breast cancer remains poorly understood. The aim of this study was to evaluate the expression of VM-associated microRNAs in tumors of metastatic breast cancer patients. Firstly, we constructed microRNAs/mRNAs coregulation networks using expression data from TCGA databases. Dozens of microRNAs regulating genes involved in VM and metastasis were found. Of these, we selected 10 microRNAs for further characterization. The presence of VM in histological samples from patients with or without metastasis was evaluated using CD31-/PAS+ immunophenotyping. Remarkably, data showed that VM was significantly increased in tumors from patients with metastasis in comparison with no-metastatic group. Gene expression analysis indicated that miR-145, miR-142-3p, miR-31, miR-148a, miR-200b-3p and miR-526b were downregulated in primary tumors from patients with metastatic disease and positive for VM. Moreover, modulated microRNAs showed a predictive clinical value in overall survival in a cohort (n=1262) of breast cancer patients. Of these, we evaluated the role of miR-145 in formation of hypoxia-induced 3D channels-like using an in vitro model that recapitulates the early stages of VM. Data showed that miR-145 mimics was able to abolish the VM development in both metastatic Hs578t and MDA-MB-231 breast cancer cells. In conclusion, manipulation of miR-145 levels may represent a therapeutic approach in metastatic breast cancer patients that developed VM.

7.
Nutrients ; 14(22)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36432504

RESUMO

Gestational diabetes (GD), pre-gestational diabetes (PD), and pre-eclampsia (PE) are morbidities affecting gestational health which have been associated with dysbiosis of the mother's gut microbiota. This study aimed to assess the extent of change in the gut microbiota diversity, short-chain fatty acids (SCFA) production, and fecal metabolites profile in a sample of Mexican women affected by these disorders. Fecal samples were collected from women with GD, PD, or PE in the third trimester of pregnancy, along with clinical and biochemical data. Gut microbiota was characterized by high-throughput DNA sequencing of V3-16S rRNA gene libraries; SCFA and metabolites were measured by High-Pressure Liquid Chromatography (HPLC) and (Fourier Transform Ion Cyclotron Mass Spectrometry (FT-ICR MS), respectively, in extracts prepared from feces. Although the results for fecal microbiota did not show statistically significant differences in alfa diversity for GD, PD, and PE concerning controls, there was a difference in beta diversity for GD versus CO, and a high abundance of Proteobacteria, followed by Firmicutes and Bacteroidota among gestational health conditions. DESeq2 analysis revealed bacterial genera associated with each health condition; the Spearman's correlation analyses showed selected anthropometric, biochemical, dietary, and SCFA metadata associated with specific bacterial abundances, and although the HPLC did not show relevant differences in SCFA content among the studied groups, FT-ICR MS disclosed the presence of interesting metabolites of complex phenolic, valeric, arachidic, and caprylic acid nature. The major conclusion of our work is that GD, PD, and PE are associated with fecal bacterial microbiota profiles, with distinct predictive metagenomes.


Assuntos
Diabetes Gestacional , Microbioma Gastrointestinal , Pré-Eclâmpsia , Gravidez , Humanos , Feminino , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/análise , Disbiose/microbiologia , Fezes/microbiologia , Ácidos Graxos Voláteis/metabolismo , Bactérias
8.
Diagnostics (Basel) ; 12(11)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36428893

RESUMO

The COVID-19 pandemic has been a main concern over the last two years and has become one of the most important crises in the history of human health. Today, there is still a need for affordable and reliable diagnostic tests for massive disease monitoring. Previously, a set of highly specific DNA-aptamers (C7/C9) binding to the SARS-CoV-2 Spike (S) protein were isolated but its performance in clinical samples remained to be tested. Here, 242 samples were collected through three different methods and subjected to florescence-linked aptamer assays (FLAA) based on C7/C9 aptamers through two readout protocols. Then, a step-by-step statistical approach which included agreement tests, proportion comparisons and binomial and multinomial logistic regressions was used to predict optimal conditions for the novel C7/C9 FLAA test. RTqPCR threshold cycles, symptoms onset and processing time were influential factors on FLAA test results. Naturally occurring mutations on S were also detected and analyzed. Aminoacidic substitutions D614G and T732A appeared relevant for aptamer recognition although further studies are necessary. The methodology presented here is the first step to determine the performance and diagnosis across a range of clinical contexts and it might serve as a base for a complete analysis applicable to other designs of new diagnostic tests.

9.
Appl Microbiol Biotechnol ; 106(23): 7905-7916, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36342507

RESUMO

The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been one of the most catastrophic diseases observed in recent years. It has reported nearly 550 million cases worldwide, with more than 6.35 million deaths. In Mexico, an increased incidence and mortality of this disease were observed, where the immune response has been involved in the magnitude and severity. A critical version of the disease is accompanied by hyperinflammatory responses, with cytokine and defective cellular responses. A detailed understanding of the role of molecules and cells in the immune response during COVID-19 disease may help to generate effective protection mechanisms, improving those we already have. Here we analyzed blood samples obtained from patients at the Hospital Regional de Alta Especialidad de Ixtapaluca (HRAEI), Mexico, which were classified according to living guidance for clinical management of COVID-19 by the World Health Organization: asymptomatic, mild, severe, and critical disease. We observed increased interleukin (IL)-6 levels and a T-CD8+ and T-CD4+ cell reduction correlated with the critical disease version. Importantly, here, we described a significant reduction of CD11b+CD45highCD14low monocytes during severe disease, which displayed a non-classical profile, expressing IL-10, transforming growth factor (TGF)-ß, and indoleamine 2,3-dioxygenase (IDO)1 molecule. Moreover, CD11b+CD45highCD14low monocytes obtained from infected one-dose vaccinated patients (Pfizer® vaccine) who suffered minimal symptoms showed simultaneously a dual classical and no-classical profile expressing pro- and anti-inflammatory cytokines. These results suggest that blood monocytes expressing a dual pro- and anti-inflammatory profile might be a predictive marker for protection in the Mexican population during COVID-19 disease. KEY POINTS : • Exacerbated immune response is associated with COVID-19 severe disease. • Dual monocyte activation profile is crucial for predicting protection during COVID-19. • Vaccination is crucial to induce the dual activation profile in monocytes.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Pandemias/prevenção & controle , Monócitos/metabolismo , México , Citocinas/metabolismo
10.
Pathogens ; 11(11)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36364979

RESUMO

COVID-19-associated pulmonary aspergillosis (CAPA) has had a high incidence. In addition, it has been associated with prolonged hospital stays, as well as several predisposing risk factors, such as fungal factors (nosocomial organism, the size of the conidia, and the ability of the Aspergillus spp. of colonizing the respiratory tract), environmental factors (remodeling in hospitals, use of air conditioning and negative pressure in intensive care units), comorbidities, and immunosuppressive therapies. In addition to these factors, SARS-CoV-2 per se is associated with significant dysfunction of the patient's immune system, involving both innate and acquired immunity, with reduced CD4+ and CD8+ T cell counts and cytokine storm. Therefore, this review aims to identify the factors influencing the fungus so that coinfection with SARS-CoV-2 can occur. In addition, we analyze the predisposing factors in the fungus, host, and the immune response alteration due to the pathogenicity of SARS-CoV-2 that causes the development of CAPA.

11.
Vaccines (Basel) ; 10(3)2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35335046

RESUMO

As a result of the COVID-19 pandemic, various joint efforts have been made to support the creation of vaccines. Different projects have been under development, of which some are in the clinical evaluation stage and others in are in phase III with positive results. The aim of this paper was to describe the current situation of the development and production of vaccines available to the population to facilitate future research and continue developing and proposing ideas for the benefit of the population. So, we carried out a systematic review using databases such as PubMed, ScienceDirect, SciELO, and MEDLINE, including keywords such as "vaccines," "COVID-19," and "SARS-CoV-2". We reviewed the development and production of the anti-COVID vaccine and its different platforms, the background leading to the massive development of these substances, and the most basic immune aspects for a better understanding of their physiological activity and the immune response in those who receive the vaccine. We also analyzed immunization effects in populations with any medical or physiological conditions (such as immunosuppression, people with comorbidities, and pregnancy), as well as the response to immunization with heterologous vaccines and the hybrid immunity (the combination of natural immunity to SARS-CoV-2 with immunity generated by the vaccine). Likewise, we address the current situation in Mexico and its role in managing the vaccination process against SARS-CoV-2 at the national and international levels. There are still many clinical and molecular aspects to be described, such as the duration of active immunity and the development of immunological memory, to mention some of the most important ones. However, due to the short time since the global vaccination roll-out and that it has been progressive (not counting children and people with medical conditions), it is premature to say whether a second vaccination schedule will be necessary for the near future. Thus, it is essential to continue with health measures.

12.
Microorganisms ; 10(2)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35208828

RESUMO

Systemic candidiasis is a frequent opportunistic mycosis that can be life-threatening. Its main etiological agent is Candida albicans; however, the isolation of non-albicans Candida species has been increasing. Some of these species exhibit greater resistance to antifungals, so the rapid and specific identification of yeasts is crucial for a timely diagnosis and optimal treatment of patients. Multiple molecular assays have been developed, based mainly on polymerase chain reaction (PCR), showing high specificity and sensitivity to detect and identify Candida spp. Nevertheless, its application in diagnosis has been limited due to specialized infrastructure or methodological complexity. The objective of this study was to develop a PCR assay that detects and identifies some of the most common pathogenic Candida species and evaluate their diagnostic utility in blood samples and bronchial lavage. A pair of oligonucleotides was designed, CandF and CandR, based on sequence analysis of the 18S-ITS1-5.8S-ITS2-28S region of the rDNA of Candida spp., deposited in GenBank. The designed oligonucleotides identified C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. krusei/Pichia kudriazevii, C. guilliermondii/Meyerozyma guilliermondii, C. lusitaniae/Clavispora lusitaniae, and C. dubliniensis using simplex PCR based on the amplicon size, showing a detection limit of 10 pg/µL of DNA or 103 yeasts/mL. Based on cultures as the gold standard, it was determined that the sensitivity (73.9%), specificity (96.3%), and the positive (94.4%) and negative (81.2%) predictive values of the PCR assay with the designed oligonucleotides justify their reliable use in diagnosis.

13.
Fam Pract ; 39(3): 515-518, 2022 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34910137

RESUMO

BACKGROUND: We aimed to describe the use of drugs with apparent efficacy in ambulatory patients with confirmed COVID-19 and the relationship of Google Trends searches with prescriptions and the total number of COVID-19 cases in Mexico City. METHODS: Between March 2020 and February 2021, we surveyed 350 patients confirmed to have COVID-19 across 3 hospitals in Mexico City for their ambulatory prescriptions. We analysed the correlation between prescription patterns of 4 drugs with apparent efficacy against COVID-19, Google Trends searches for these drugs, and the overall number of confirmed COVID-19 cases in Mexico City. RESULTS: We included 350 patients, of whom 59% were women with a median age of 38 years (interquartile range, 29-51), and 72% had a bachelor's degree or higher. There were ambulatory medical prescriptions in 172 (49%) patients, and self-prescriptions were reported in 99 (28%) patients. The prescription rate was high for hydroxychloroquine/azithromycin (19%) and dexamethasone (25%). There was a decrease in the prescription of hydroxychloroquine (P < 0.001) and a strong positive correlation between hydroxychloroquine (r = 0.66; 95% confidence interval, 0.11-0.90; P = 0.02) prescription and online searches for hydroxychloroquine. There was a strong positive correlation between online searches for azithromycin, dexamethasone, ivermectin, and vitamin D and the number of confirmed COVID-19 cases. CONCLUSIONS: During the COVID-19 pandemic, there was a high proportion of prescriptions for hydroxychloroquine/azithromycin and dexamethasone despite their unproven efficacy. Analysis of Google Trends showed a strong correlation between the overall number of confirmed COVID-19 cases and searches for such drugs, suggesting a higher rate of prescriptions. Analysis of online searches could thus help to actively survey public health behaviours in the future.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Adulto , Azitromicina , COVID-19/epidemiologia , Dexametasona , Prescrições de Medicamentos , Feminino , Humanos , Hidroxicloroquina/uso terapêutico , Masculino , México/epidemiologia , Pacientes Ambulatoriais , Pandemias , SARS-CoV-2
14.
J Fungi (Basel) ; 7(7)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34356935

RESUMO

The physiopathologic characteristics of COVID-19 (high levels of inflammatory cytokines and T-cell reduction) promote fungal colonization and infection, which can go unnoticed because the symptoms in both diseases are very similar. The objective of this work was to study the current epidemiology of systemic mycosis in COVID-19 times. A literature search on the subject (January 2020-February 2021) was performed in PubMed, Embase, Cochrane Library, and LILACS without language restrictions. Demographic data, etiological agent, risk factors, diagnostic methods, antifungal treatment, and fatality rate were considered. Eighty nine publications were found on co-infection by COVID-19 and pneumocystosis, candidiasis, aspergillosis, mucormycosis, coccidioidomycosis, or histoplasmosis. In general, the co-infections occurred in males over the age of 40 with immunosuppression caused by various conditions. Several species were identified in candidiasis and aspergillosis co-infections. For diagnosis, diverse methods were used, from microbiological to molecular. Most patients received antifungals; however, the fatality rates were 11-100%. The latter may result because the clinical picture is usually attributed exclusively to SARS-CoV-2, preventing a clinical suspicion for mycosis. Diagnostic tests also have limitations beginning with sampling. Therefore, in the remainder of the pandemic, these diagnostic limitations must be overcome to achieve a better patient prognosis.

15.
Rev Iberoam Micol ; 38(3): 119-124, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33839018

RESUMO

BACKGROUND: The molecular reclassification of the order Trichosporonales placed the medically relevant Trichosporon species into three genera of the family Trichosporonaceae: Cutaneotrichosporon, Trichosporon, and Apiotrichum. From the clinical and epidemiological standpoint, it is important to identify any species of the family Trichosporonaceae because they present different antifungal susceptibility profiles. In Mexico, little is known about trichosporonosis etiology because the fungi are identified through phenotypic methods. AIMS: To identify at a molecular level 12 yeast isolates morfologically compatible with Trichosporon, obtained from patients with superficial infections. METHODS: The yeast isolates were obtained from patients with white piedra, onychomycosis, and hand and foot dermatomycosis, and were identified morphologically and genotypically (sequencing of the IGS1 region and phylogenetic analysis using the Maximum Likelihood Method). The phylogenetic analysis included 40 yeast sequences from the order Trichosporonales and one from Cryptococcus neoformans as outgroup. RESULTS: Based on the molecular analysis, we identified three (25%) Trichosporon inkin isolates, two (16.7%) Trichosporon asteroides, two (16.7%) Cutaneotrichosporon mucoides, and one each (8.3%) of Trichosporon aquatile, Trichosporon asahii, Apiotrichum montevideense, Cutaneotrichosporon cutaneum, and Cutaneotrichosporon jirovecii. CONCLUSIONS: The molecular characterization of the isolates showed a broad diversity of species within the order Trichosporonales, particularly among onychomycosis. It is essential to identify these yeasts at the species level to delve into their epidemiology.


Assuntos
Cryptococcus neoformans , Trichosporon , Basidiomycota , Humanos , Filogenia , Trichosporon/genética
16.
Antibiotics (Basel) ; 9(9)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887362

RESUMO

Since Candida auris integrates strains resistant to multiple antifungals, research has been conducted focused on knowing which molecular mechanisms are involved. This review aims to summarize the results obtained in some of these studies. A search was carried out by consulting websites and online databases. The analysis indicates that most C. auris strains show higher resistance to fluconazole, followed by amphotericin B, and less resistance to 5-fluorocytosine and caspofungin. In C. auris, antifungal resistance to amphotericin B has been linked to an overexpression of several mutated ERG genes that lead to reduced ergosterol levels; fluconazole resistance is mostly explained by mutations identified in the ERG11 gene, as well as a higher number of copies of this gene and the overexpression of efflux pumps. For 5-fluorocytosine, it is hypothesized that the resistance is due to mutations in the FCY2, FCY1, and FUR1 genes. Resistance to caspofungin has been associated with a mutation in the FKS1 gene. Finally, resistance to each antifungal is closely related to the type of clade to which the strain belongs.

17.
Microorganisms ; 8(5)2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32397318

RESUMO

The CSP (cell surface protein) microsatellite marker is useful for typing Aspergillus fumigatus isolates and determining relationships at the subpopulation level because it has shown high discriminatory power. In the present study, 90 A. fumigatus isolates from Mexico (MX), Argentina (AR), France (FR), and Peru (PE) were identified through a phylogenetic analysis using the benA gene fragment and were typed with the CSP microsatellite, and the types were identified using the nomenclature recommended in the literature. Genetic variability was analyzed through haplotype diversity, nucleotide diversity, polymorphic sites, and nucleotide differences between pairs of sequences. The population structure was evaluated using the Tajima's D statistic. No new CSP types were recorded in the MX, FR, and PE isolates, while in the AR isolates, two new CSP types were identified (t25 and t26). The most common CSP types in the studied populations were t01, t02, t03, and t04A; these results are consistent with findings in other countries. In addition, the genetic diversity parameters we obtained revealed that the greatest genetic diversity was found in the MX population, followed by AR and FR. No population structure was identified among the isolates studied.

18.
Braz J Infect Dis ; 23(5): 322-330, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31539511

RESUMO

At present, there is no standardized marker that is routinely used in clinical laboratories to diagnose coccidioidomycosis. Thus, the goals of this study were to obtain a sequence characterized amplified region (SCAR) marker for the identification of Coccidioides spp., evaluate its specificity and sensitivity in fungal DNA-spiked blood and sputum samples, and compare it with previously described molecular markers. Specific amplified fragment length polymorphism (AFLP) amplicons for Coccidioides immitis and Coccidioides posadasii were cloned into the vector pGEM® -T Easy vector and sequenced to develop a SCAR marker. Oligonucleotides were designed to identify Coccidioides spp. by polymerase chain reaction (PCR), and the specificity and sensitivity of these oligonucleotides were tested with the DNA from related pathogens. The specificity and sensitivity of the SCAR marker was evaluated with blood and sputum samples spiked with Coccidioides DNA and compared with other previously described markers (621, GAC2, and Ag2/PRA). In addition, the conditions for its use were established using biological samples. A specific marker named SCAR300 was obtained to identify Coccidioides spp. that exhibited good sensitivity and specificity. The results showed that all of the markers tested in this study can identify Coccidioides spp. However, the SCAR300 and 621 markers were the most sensitive, whereas the SCAR300 marker was the most specific. Thus, the SCAR300 marker is a useful tool to identify Coccidioides spp.


Assuntos
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Coccidioides/genética , Coccidioidomicose/diagnóstico , DNA Fúngico/genética , Sequência de Bases , Coccidioides/classificação , Coccidioides/isolamento & purificação , Coccidioidomicose/microbiologia , Humanos , Reação em Cadeia da Polimerase , Polimorfismo Genético , Sensibilidade e Especificidade
19.
Rev Inst Med Trop Sao Paulo ; 61: e37, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31411267

RESUMO

Candida glabrata complex includes three species identified through molecular biology methods: C. glabrata sensu stricto , C. nivariensis and C. bracarensis . In Mexico, the phenotypic methods are still used in the diagnosis; therefore, the presence of C. nivariensis and C. bracarensis among clinical isolates is still unknown. The aim of this study was to evaluate the utility of a multiplex PCR for the identification of the C. glabrata species complex. DNA samples from 92 clinical isolates that were previously identified through phenotypic characteristics as C. glabrata were amplified by four oligonucleotides (UNI-5.8S, GLA-f, BRA-f, and NIV-f) that generate amplicons of 397, 293 and 223-bp corresponding to C. glabrata sensu stricto , C. nivariensis , and C. bracarensis , respectively. The amplicon sequences were used to perform a phylogenetic analysis through the Maximum Likelihood method (MEGA6), including strains and reference sequences of species belonging to C. glabrata complex. In addition, recombination and linkage disequilibrium were estimated (DnaSP version 5.0) for C. glabrata sensu stricto isolate s . Eighty-eight isolates generated a 397-bp fragment and only in one isolate a 223-bp amplicon was observed. In the phylogenetic tree, the sequences of 397-bp were grouped with C. glabrata reference sequences , and the sequence of 223-bp was grouped with C. bracarensis reference sequences, corroborating the PCR identification. The number of recombination events for the isolates of C. glabrata sensu stricto was zero, suggesting a clonal population structure. Three isolates that did not amplify any of the expected fragments were identified as Saccharomyces cerevisiae through the sequencing of the D1/D2 domain region within the 28S rDNA gene. The multiplex PCR is a fast, cost-effective and reliable tool that can be used in clinical laboratories to identify C. glabrata complex species.


Assuntos
Candida glabrata/genética , Candidíase/microbiologia , DNA Fúngico/genética , Técnicas de Tipagem Micológica/métodos , Candida glabrata/isolamento & purificação , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Feminino , Humanos , Masculino , México , Reação em Cadeia da Polimerase Multiplex , Filogenia , Análise de Sequência de DNA
20.
Infect Genet Evol ; 75: 103960, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31325612

RESUMO

The Candida haemulonii species complex and other phylogenetically related species, such as Candida auris, are emerging pathogens. The C. haemulonii complex comprises C. haemulonii, C. haemulonii var. vulnera, and Candida duobushaemulonii species. The correct identification of this fungal complex is clinically and epidemiologically relevant; however, conventional identification methods are currently inadequate. In this study, we report the molecular reidentification of two clinical isolates: isolate 553 that was recovered from a patient with total dystrophic onychomycosis and isolate 77-18 from a patient with mucocutaneous candidiasis. Both patients had diabetes mellitus as baseline disease. These isolates were initially identified as C. haemulonii by the VITEK® 2 system but were later determined to be C. duobushaemulonii based on the amplification and sequencing of a 115-bp fragment of the region of 26S rDNA. The isolates were resistant to fluconazole, and only isolate 553 was resistant to amphotericin B. Patients showed clinical and mycological cure after treatment with itraconazole. The clinical and microbiological data of these two cases of superficial candidiasis caused by C. duobushaemulonii, along with previous reports about infections with the C. haemulonii complex species, suggest that patients with diabetes mellitus are highly susceptible to infection with these fungi. Therefore, for diagnosing candidiasis in patients with diabetes mellitus, yeasts must be identified at the species level, and antifungal susceptibility testing must be carried out for adequate treatment.


Assuntos
Antifúngicos/farmacologia , Candida/classificação , Candidíase/microbiologia , Dermatomicoses/microbiologia , Adulto , Idoso , Candida/genética , Candidíase/tratamento farmacológico , Dermatomicoses/tratamento farmacológico , Farmacorresistência Fúngica , Humanos , Masculino , Especificidade da Espécie
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