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1.
Artículo en Inglés | MEDLINE | ID: mdl-38989592

RESUMEN

Background: Coxiella burnetii, an obligate intracellular bacterium, is the etiological agent of Q fever in humans and one of the causes of abortion in small ruminants. Although coxiellosis is considered an exotic disease, there are a few reports in Mexico. Methods: The objective of this work was to determine the presence of C. burnetii DNA in vaginal samples from sheep that presented abortion and ram semen. A total of 180 vaginal exudate samples and 20 semen samples were obtained from five Central and Southern States of Mexico. Total DNA was extracted from vaginal swabs and C. burnetii was identified by PCR amplification and sequencing of the IS1111 insertion sequence. Results and Conclusion: In total, 110 (110/180) vaginal samples and 12 (12/20) semen samples were positive for C. burnetii. This is the first report of C. burnetii in sheep that aborted and in ram semen in Mexico.

2.
J Infect Dev Ctries ; 18(6): 978-981, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38990993

RESUMEN

INTRODUCTION: Mycetoma is a chronic granulomatous inflammatory disease of the subcutaneous tissue, which affects deep structures and bone. Most cases of actinomycetoma are caused by members of the genus Nocardia. CASE PRESENTATION: Here we report the case of a 43-year-old male who presented a disseminated mycetoma on the forearm, chest and neck, characterized by enlarged and erythematous lesions through which seropurulent material drains, and numerous atrophic scars. Molecular identification was performed by 16S gene amplification and sequencing. Nocardia mexicana was identified with 100% identity. Trimethoprim-sulfamethoxazole, diaminodiphenyl sulfone and amikacin was a successful treatment after 6 months. CONCLUSIONS: Nocardia mexicana is a rare organism that causes mycetoma. We report a case of extensive mycetoma on the forearm with spread to the neck and thorax associated with manipulation of the mouth of a calf.


Asunto(s)
Antibacterianos , Antebrazo , Micetoma , Cuello , Nocardiosis , Nocardia , ARN Ribosómico 16S , Tórax , Humanos , Masculino , Adulto , Nocardia/aislamiento & purificación , Nocardia/genética , Micetoma/microbiología , Micetoma/tratamiento farmacológico , Micetoma/diagnóstico , Nocardiosis/microbiología , Nocardiosis/tratamiento farmacológico , Nocardiosis/diagnóstico , Antebrazo/microbiología , Antebrazo/patología , Tórax/diagnóstico por imagen , Tórax/microbiología , Cuello/patología , Antibacterianos/uso terapéutico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Resultado del Tratamiento , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Amicacina/uso terapéutico , ADN Ribosómico/genética , ADN Ribosómico/química
3.
Artículo en Inglés | MEDLINE | ID: mdl-38747851

RESUMEN

Microsporum canis, one of the most widespread dermatophytes worldwide, is a zoonotic microorganism that transmits infection from reservoirs such as cats and dogs to humans. This microorganism is associated with Tinea corporis and other clinical manifestations; however, few studies have used genetic surveillance to determine and characterize the process of zoonotic transmission. In this study, we show a clear example of zoonotic transmission from a cat to an intrafamilial environment, where it caused Tinea corporis by infection with M. canis. Molecular characterization using the b-tubulin gene and Random Amplified Polymorphic DNA analysis made it possible to determine that the six isolates of M. canis obtained in this study belonged to the same genetic variant or clone responsible for reservoir-reservoir or reservoir-human transmission.


Asunto(s)
Enfermedades de los Gatos , Microsporum , Tiña , Zoonosis , Microsporum/aislamiento & purificación , Microsporum/genética , Microsporum/clasificación , Gatos/microbiología , Animales , Tiña/microbiología , Tiña/transmisión , Tiña/veterinaria , Enfermedades de los Gatos/microbiología , Enfermedades de los Gatos/transmisión , Zoonosis/microbiología , Zoonosis/transmisión , Mascotas/microbiología , Humanos , Perros , Técnica del ADN Polimorfo Amplificado Aleatorio , Masculino , Femenino , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/transmisión , ADN de Hongos/genética
4.
Vet Res Commun ; 48(1): 49-60, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37490241

RESUMEN

Salmonella's virulence genes are located in two regions known as Salmonella pathogenicity islands 1 and 2 (SPI-1 and SPI-2). SPI-1 allows the bacteria to invade the intestine, while SPI-2 is important for intracellular survival and replication, although it is also necessary for intestinal disease. The aim of this study was to evaluate the effect of the deletion of SPI-1 or SPI-2 genes on the intestinal and systemic salmonellosis using the avian model. Groups of chickens were orally infected with 1010 Colony-Forming Units (CFU) of S. Typhimurium SL1344 WT strain, as well as mutants ∆SPI-1 or ∆SPI-2. At different times post-infection, 5 chickens from each group were euthanized and examined postmortem. Cecum and liver were taken from each chicken for determination of CFU's, histopathological analysis and immunochemistry. Bacterial colonies were recovered from the liver and cecum samples infected with WT strain, while in the cultures from the organs infected with the mutant strains no colonies were recovered or were drastically affected in the ability to survive. In histopathological analysis, the WT strain produced lesions in liver and ceca, and it was detected by immunohistochemistry throughout the course of the infection. On the other hand, organs of chickens infected with ∆SPI-1 or ∆SPI-2 showed attenuated lesions and the immunohistochemistry revealed less bacteria compared to the WT strain. Taken together, our results show the importance of SPI-1 and SPI-2 genes for the complete intestinal and systemic disease in an in vivo avian model.


Asunto(s)
Pollos , Péptidos y Proteínas de Señalización Intercelular , Salmonelosis Animal , Animales , Pollos/genética , Islas Genómicas/genética , Intestinos , Salmonella/genética , Proteínas Bacterianas/genética
5.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1559119

RESUMEN

ABSTRACT Microsporum canis, one of the most widespread dermatophytes worldwide, is a zoonotic microorganism that transmits infection from reservoirs such as cats and dogs to humans. This microorganism is associated with Tinea corporis and other clinical manifestations; however, few studies have used genetic surveillance to determine and characterize the process of zoonotic transmission. In this study, we show a clear example of zoonotic transmission from a cat to an intrafamilial environment, where it caused Tinea corporis by infection with M. canis. Molecular characterization using the b-tubulin gene and Random Amplified Polymorphic DNA analysis made it possible to determine that the six isolates of M. canis obtained in this study belonged to the same genetic variant or clone responsible for reservoir-reservoir or reservoir-human transmission.

6.
Antibiotics (Basel) ; 12(12)2023 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-38136747

RESUMEN

Chromoblastomycosis is a chronic granulomatous mycosis of the skin and subcutaneous tissue caused by traumatic inoculation with dematiaceous fungi. This disease primarily affects agricultural workers, who are mostly men. We present a case of chromoblastomycosis in a 63-year-old male farmer patient with dermatosis over 50 years of evolution, with warty, erythematous, and scaly plaques that predominate on the left hemithorax. Direct examination with potassium hydroxide (KOH) revealed numerous fumagoid cells. Amplification and sequencing of the internal transcribed spacer (ITS) and translation elongation factor 1-alpha (TEF-1a) gene revealed that chromoblastomycosis was caused by Cladosporium cladosporioides. The chromoblastomycosis was treated with itraconazole and fluconazole without any improvement, and amphotericin B was administered with partial improvement.

7.
Jpn J Infect Dis ; 75(4): 427-430, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35354704

RESUMEN

The causative agents of leprosy are Mycobacterium leprae and M. lepromatosis. Mycobacterium lepromatosis was found in 2008 to cause diffuse lepromatous leprosy in Mexican patients. This study aimed to identify M. leprae and M. lepromatosis in paraffin-embedded skin samples from Caribbean patients with leprosy. A total of six skin samples were obtained from the Dominican Republic. All cases presented the multibacillary form; five were nodular lepromatous leprosy, and one was borderline lepromatous leprosy. All patients received multidrug therapy. Molecular identification was achieved using the M. leprae-specific repetitive element for M. leprae and the hemN gene for M. lepromatosis. Mycobacterium leprae was identified in two lepromatous leprosy cases, and one borderline lepromatous leprosy case; M. lepromatosis was found in one nodular lepromatous leprosy case. Both Mycobacterium species were present in two nodular lepromatous leprosy cases. This is the first report of M. lepromatosis in the Dominican Republic.


Asunto(s)
Lepra Lepromatosa , Lepra , República Dominicana , Quimioterapia Combinada , Humanos , Leprostáticos/uso terapéutico , Mycobacterium , Mycobacterium leprae/genética
8.
J Mycol Med ; 32(1): 101204, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34598111

RESUMEN

Chromoblastomycosis is a chronic subcutaneous mycosis caused by traumatic inoculation of dematiaceous fungi especially in tropical and subtropical areas. Cyphellophora genus include melanized fungi reported as etiological agents of skin and nail infections. We report a 60-year-old male from the south of Mexico with a 40-year history of chromoblastomycosis caused by Cyphellophora laciniata. The isolated fungus was identified by sequencing of the internal transcribed spacer region of rDNA. The patient was treated with itraconazole and cryosurgery with unsatisfactory results.


Asunto(s)
Ascomicetos , Cromoblastomicosis , Antifúngicos/uso terapéutico , Ascomicetos/genética , Cromoblastomicosis/diagnóstico , Cromoblastomicosis/tratamiento farmacológico , Cromoblastomicosis/microbiología , Humanos , Itraconazol/uso terapéutico , Masculino , Persona de Mediana Edad
9.
J Mycol Med ; 31(2): 101114, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33684836

RESUMEN

Chromoblastomycosis is a chronic subcutaneous fungal infection caused by melanized fungi. It is usually an occupational mycosis affecting people in rural areas in tropical and subtropical regions. We present two cases of chromoblastomycosis in Mexican farmers, characterized by skin verrucous plaques. Direct examination with KOH 10% showed the presence of muriform cells. The fungal isolation was carried out in Sabouraud dextrose agar and molecular identification was achieved by 18S-ITS1-5.8S-ITS2-28S rRNA gene amplification and sequencing. Fonsecaeamonophora was identified in both cases. A therapy with itraconazole and terbinafine was used with a partial favorable response. However, patients did not return for medical examination after 4 months. The current status of the patients is unknown. We reported the first two cases of chromoblastomycosis caused by F. monophora in Mexico.


Asunto(s)
Antifúngicos/farmacología , Cromoblastomicosis/diagnóstico , Fonsecaea/efectos de los fármacos , Fonsecaea/genética , Piel/microbiología , Adulto , Anciano , Antifúngicos/uso terapéutico , Cromoblastomicosis/tratamiento farmacológico , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Agricultores , Fonsecaea/clasificación , Fonsecaea/patogenicidad , Humanos , Masculino , México , Pruebas de Sensibilidad Microbiana , Análisis de Secuencia de ADN , Piel/patología
10.
Braz J Microbiol ; 52(2): 1029-1036, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33580865

RESUMEN

Bovine mastitis, an inflammation of the mammary gland of dairy cattle, is the most prevalent disease causing economically important losses, reduced milk production, early culling, veterinary expenses, and higher death rates. Bovine mastitis infections are the main cause for the use of antibiotics; however, the emergence of multidrug-resistant bacteria and the poor or nil response to antibiotics has become a critical global health problem. The goal of this study was the characterization of bacterial infections associated with clinical bovine mastitis. All the isolates were multidrug-resistant and were negative for the production of extended spectrum ß-lactamases. However, all isolates were identified as carbapenemase-producing organisms by the Carba NP test. The carbapenemase identified was the product of the KPC-2 gene. The isolates were identified as Klebsiella pneumoniae and contained virulence genes for fimbriae, lipopolysaccharides, nitrogen starvation genes, and siderophores. Sixty-nine percent of the KPC-2-producing isolates had the same plasmid profile, although the genetic mobilization of resistance by bacterial conjugation was unsuccessful. The carbapenemase corresponded to the plasmid-borne KPC-2 gene identified by Southern blot hybridization. The assay showed a positive signal in the 90 kb (69% of the isolates), 165 kb (31% of the isolates), and 130 kb (6% of the isolates) plasmids. The IncFIIy and IncFIIk replicons were detected among these K. pneumoniae isolates. The PFGE and MLST analysis showed that all of the isolates are comprised by two clones (A and B) belonging to Sequence Type 258. This is the first report of K. pneumoniae producing carbapenemase KPC-2 isolated from bovine mastitis.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Infecciones por Klebsiella/veterinaria , Klebsiella pneumoniae/aislamiento & purificación , Mastitis Bovina/microbiología , beta-Lactamasas/metabolismo , Animales , Antibacterianos/farmacología , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/enzimología , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Bovinos , Farmacorresistencia Bacteriana Múltiple , Femenino , Genotipo , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/enzimología , Klebsiella pneumoniae/genética , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Virulencia/genética , beta-Lactamasas/genética
11.
Braz J Microbiol ; 51(4): 2009-2014, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32897511

RESUMEN

Using molecular and whole-genome sequencing tools, we investigated colistin-resistant Escherichia coli isolates from wild sea lions. Two unrelated E. coli colistin-resistant isolates, ST8259 and ST4218, were identified, both belonging to the B2 phylogroup and different serotypes. Polymorphisms in PmrA, PmrB, and PhoQ proteins were identified, and the role of PmrB and PhoQ in contributing to colistin resistance was determined by complementation assays. However, the mutations characterized in the present study are not involved in colistin resistance, which have been described in E. coli isolates from clinical settings. Therefore, the acquired mutations in pmrB and phoQ genes in resistance to colistin in bacteria related to marine environment animals are different. This work contributes to the surveillance and characterization of colistin resistance in Escherichia coli obtained from animals from aquatic environments.


Asunto(s)
Antibacterianos/farmacología , Colistina/farmacología , Escherichia coli/clasificación , Escherichia coli/efectos de los fármacos , Genoma Bacteriano , Leones Marinos/microbiología , Animales , Animales Salvajes/microbiología , Farmacorresistencia Bacteriana Múltiple/genética , Proteínas de Escherichia coli/genética , Pruebas de Sensibilidad Microbiana , Serogrupo , Secuenciación Completa del Genoma
12.
J Bacteriol ; 202(11)2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-32205462

RESUMEN

While alternating between insects and mammals during its life cycle, Yersinia pestis, the flea-transmitted bacterium that causes plague, regulates its gene expression appropriately to adapt to these two physiologically disparate host environments. In fleas competent to transmit Y. pestis, low-GC-content genes y3555, y3551, and y3550 are highly transcribed, suggesting that these genes have a highly prioritized role in flea infection. Here, we demonstrate that y3555, y3551, and y3550 are transcribed as part of a single polycistronic mRNA comprising the y3555, y3554, y3553, y355x, y3551, and y3550 genes. Additionally, y355x-y3551-y3550 compose another operon, while y3550 can be also transcribed as a monocistronic mRNA. The expression of these genes is induced by hyperosmotic salinity stress, which serves as an explicit environmental stimulus that initiates transcriptional activity from the predicted y3550 promoter. Y3555 has homology to pyridoxal 5'-phosphate (PLP)-dependent aromatic aminotransferases, while Y3550 and Y3551 are homologous to the Rid protein superfamily (YjgF/YER057c/UK114) members that forestall damage caused by reactive intermediates formed during PLP-dependent enzymatic activity. We demonstrate that y3551 specifically encodes an archetypal RidA protein with 2-aminoacrylate deaminase activity but Y3550 lacks Rid deaminase function. Heterologous expression of y3555 generates a critical aspartate requirement in a Salmonella entericaaspC mutant, while its in vitro expression, and specifically its heterologous coexpression with y3550, enhances the growth rate of an Escherichia coli ΔaspC ΔtyrB mutant in a defined minimal amino acid-supplemented medium. Our data suggest that the y3555, y3551, and y3550 genes operate cooperatively to optimize aromatic amino acid metabolism and are induced under conditions of hyperosmotic salinity stress.IMPORTANCE Distinct gene repertoires are expressed during Y. pestis infection of its flea and mammalian hosts. The functions of many of these genes remain predicted or unknown, necessitating their characterization, as this may provide a better understanding of Y. pestis specialized biological adaptations to the discrete environments of its two hosts. This study provides functional context to adjacently clustered horizontally acquired genes predominantly expressed in the flea host by deciphering their fundamental processes with regard to (i) transcriptional organization, (ii) transcription activation signals, and (iii) biochemical function. Our data support a role for these genes in osmoadaptation and aromatic amino acid metabolism, highlighting these as preferential processes by which Y. pestis gene expression is modulated during flea infection.


Asunto(s)
Aminoácidos Aromáticos/metabolismo , Siphonaptera/microbiología , Yersinia pestis/metabolismo , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Transferencia de Gen Horizontal , Operón , Yersinia pestis/genética , Yersinia pestis/crecimiento & desarrollo
14.
Dis Aquat Organ ; 137(2): 125-130, 2019 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-31854330

RESUMEN

Francisellosis is a disease caused by different species of the bacterial genus Francisella and has been diagnosed in a wide variety of animals, including fish. Francisellosis in fish is characterized by the development of non-specific clinical signs as well as the presence of numerous granulomas in several organs (mainly spleen and kidney). Ten neon jewel cichlids Hemichromis bimaculatus were submitted for diagnosis from a farm located in Morelos, Mexico. Gross examination, wet preparations, cytology, histopathology and PCR were performed. Affected fish showed lethargy, erratic swimming, imbalance and gasping. At the post mortem examination, multiple granulomas were observed in the kidney and spleen. Microscopically, granulomatous inflammation was observed in several organs. Species-specific PCR assay using DNA from the affected tissues of H. bimaculatus as a template demonstrated the presence of F. noatunensis subsp. orientalis (Fno) by amplifying a hypothetical protein gene of the Fno species. The end diagnosis of francisellosis is important for Mexican ornamental aquaculture, since it is necessary to implement measures for treatment, prevention, control and diagnosis. This is the first report of francisellosis in the neon jewel cichlid.


Asunto(s)
Cíclidos , Enfermedades de los Peces , Francisella , Infecciones por Bacterias Gramnegativas , Animales , Brotes de Enfermedades , México
15.
Front Microbiol ; 6: 956, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26441890

RESUMEN

Yersinia pestis, responsible for causing fulminant plague, has evolved clonally from the enteric pathogen, Y. pseudotuberculosis, which in contrast, causes a relatively benign enteric illness. An ~97% nucleotide identity over 75% of their shared protein coding genes is maintained between these two pathogens, leaving much conjecture regarding the molecular determinants responsible for producing these vastly different disease etiologies, host preferences and transmission routes. One idea is that coordinated production of distinct factors required for host adaptation and virulence in response to specific environmental cues could contribute to the distinct pathogenicity distinguishing these two species. Small non-coding RNAs that direct posttranscriptional regulation have recently been identified as key molecules that may provide such timeous expression of appropriate disease enabling factors. Here the burgeoning field of small non-coding regulatory RNAs in Yersinia pathogenesis is reviewed from the viewpoint of adaptive colonization, virulence and divergent evolution of these pathogens.

16.
Vet J ; 170(3): 359-63, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16266850

RESUMEN

Nasal swab samples from clinically healthy California sea lions pups (Zalophus californianus) from six different reproductive rookeries in the Gulf of California were collected to determine the type and frequency of the representative aerobic bacterial microflora of their nasal mucosa. A total of 114 samples were examined and 100 bacterial isolates were identified and typified by microbiological and biochemical standard tests. Fifty four isolates corresponded to Gram positive bacteria (54%) and 46 isolates to Gram negative bacteria (46%). Fifteen bacterial genera were identified, including Micrococcus, Arcanobacterium, Corynebacterium, Moraxella, Neisseria, Escherichia, Kurthia, Acinetobacter, Staphylococcus, Brevibacillus, Bacillus, Klebsiella, Stenotrophomonas, Pseudomonas and Aeromonas. The most frequently isolated genera were Moraxella (24%), Micrococcus (18%), and Corynebacterium (15%). These results show the presence in the nasal cavity of sea lions of several microorganisms. Although considered part of the normal microflora, they may also be opportunistic pathogens for their hosts and may act as a potential natural sentinel of environmental changes.


Asunto(s)
Bacterias Aerobias/aislamiento & purificación , Cavidad Nasal/microbiología , Leones Marinos , Animales , Animales Recién Nacidos
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