RESUMEN

Ureaplasma urealyticum and Mycoplasma hominis are among the most prevalent sexually transmitted infections proposed to induce urogenital inflammation and impair sperm quality. However, the topic remains controversial since contradictory findings have been reported. Herein, we performed a comprehensive analysis of U. urealyticum and M. hominis urogenital infections and their association with urogenital inflammation (i.e., leukocyte subsets and inflammatory cytokines in semen,) and sperm quality parameters in a cohort of men with couple's primary infertility undergoing initial infertility evaluation or with lower urinary tract symptoms and no infertility-related complaints. Overall, U. urealyticum and M. hominis infection was detected in 17.0% and 23.6% of patients, respectively, whereas the coinfection was detected in 3.8% of patients only. Remarkably, similar infection frequencies were found in the different patient subpopulations analyzed. Moreover, infections were associated with elevated semen levels of TNF, IL-1ß, and IL-6 and/or increased counts of total leukocytes and their subsets, including CD4 and CD8 T lymphocytes and neutrophils. In addition, M. hominis infection and the coinfection with U. urealyticum were associated with impairments in sperm quality variables. Our results indicate that U. urealyticum and M. hominis male urogenital infections induce urogenital inflammation and decrease sperm quality, thus impairing male fertility potential. Screening for U. urealyticum and M. hominis infections and performing a comprehensive analysis of different leukocyte subsets and inflammatory cytokines in semen may be clinically helpful in the diagnosis and follow-up of male urogenital infection.

Asunto(s)

Coinfección , Infecciones Urinarias , Humanos , Masculino , Semen , Ureaplasma urealyticum , Mycoplasma hominis , Espermatozoides

RESUMEN

We report two novel genosensors for the quantification of SARS-CoV-2 nucleic acid using glassy carbon electrodes modified with a biocapture nanoplatform made of multi-walled carbon nanotubes (MWCNTs) non-covalently functionalized with avidin (Av) as a support of the biotinylated-DNA probes. One of the genosensors was based on impedimetric transduction offering a non-labelled and non-amplified detection of SARS-CoV-2 nucleic acid through the increment of [Fe(CN)6]3-/4- charge transfer resistance. This biosensor presented an excellent analytical performance, with a linear range of 1.0 × 10-18 M - 1.0 × 10-11 M, a sensitivity of (5.8 ± 0.6) x 102 Ω M-1 (r2 = 0.994), detection and quantification limits of 0.33 aM and 1.0 aM, respectively; and reproducibilities of 5.4% for 1.0 × 10-15 M target using the same MWCNTs-Av-bDNAp nanoplatform, and 6.9% for 1.0 × 10-15 M target using 3 different nanoplatforms. The other genosensor was based on a sandwich hybridization scheme and amperometric transduction using the streptavidin(Strep)-biotinylated horseradish peroxidase (bHRP)/hydrogen peroxide/hydroquinone (HQ) system. This genosensor allowed an extremely sensitive quantification of the SARS-CoV-2 nucleic acid, with a linear range of 1.0 × 10-20 M - 1.0 × 10-17 M, detection limit at zM level, and a reproducibility of 11% for genosensors prepared with the same MWCNTs-Av-bDNAp1 nanoplatform. As a proof-of-concept, and considering the extremely high sensitivity, the genosensor was challenged with highly diluted samples obtained from SARS-CoV-2 RNA PCR amplification.

RESUMEN

Chlamydia trachomatis is the most common sexually transmitted bacterial pathogen in humans and a frequent cause of asymptomatic, persistent infections leading to serious complications, particularly in young women. Chlamydia displays a unique obligate intracellular lifestyle involving the infectious elementary body and the replicative reticulate body. In the presence of stressors such as gamma-interferon (IFNγ) or beta-lactam antibiotics, C. trachomatis undergoes an interruption in its replication cycle and enters a viable but non-cultivable state. Upon removal of the stressors, surviving C. trachomatis resume cell division and developmental transitions. In this report, we describe a genetic screen to identify C. trachomatis mutants with defects in recovery from IFNγ- and/or penicillin-induced stress and characterized a chemically derived C. trachomatis mutant strain that exhibited a significant decrease in recovery from IFNγ- but not penicillin-induced stress. Through lateral gene transfer and targeted insertional gene inactivation we identified ptr, encoding a predicted protease, as a gene required for recovery from IFNγ-induced stress. A C. trachomatis LGV-L2 ptr-null strain displayed reduced generation of infectious progeny and impaired genome replication upon removal of IFNγ. This defect was restored by introducing a wild type copy of ptr on a plasmid, indicating that Ptr is required for a rapid growth upon removal of IFNγ. Ptr was expressed throughout the developmental cycle and localized to the inclusion lumen. Overall, our findings indicate that the putative secreted protease Ptr is required for C. trachomatis to specifically recover from IFNγ- but not penicillin-induced stress.

RESUMEN

c-Jun is a member of the early mammalian transcriptional regulators belonging to the AP-1 family, which participates in a wide range of cellular processes such as proliferation, apoptosis, tumorigenesis, and differentiation. Despite its established role in cell survival upon stress, its participation in the stress response induced by bacterial infections has been poorly investigated. To study the potential role of c-Jun in this context we choose the widely studied α-toxin produced by Staphylococcus aureus, a pore-forming toxin that is a critical virulence factor in the pathogenesis of these bacteria. We analyzed the effect of α-toxin treatment in the activation, expression, and protein levels of c-Jun in A549 lung epithelial cells. Furthermore, we explored the role of c-Jun in the cellular fate after exposure to α-toxin. Our results show that staphylococcal α-toxin per se is able to activate c-Jun by inducing phosphorylation of its Serine 73 residue. Silencing of the JNK (c-Jun N-terminal Kinase) signaling pathway abrogated most of this activation. On the contrary, silencing of the ERK (Extracellular Signal-Regulated Kinase) pathway exacerbated this response. Intriguingly, while the exposure to α-toxin induced a marked increase in the levels of c-Jun transcripts, c-Jun protein levels noticeably decreased in the same time-frame as a consequence of active proteolytic degradation through the proteasome-dependent pathway. In addition, we established that c-Jun promoted cell survival when cells were challenged with α-toxin. Similarly, c-Jun phosphorylation was also induced in cells upon intoxication with the cytolysin produced by Vibrio cholerae in a JNK-dependent manner, suggesting that c-Jun-JNK axis would be a conserved responsive cellular pathway to pore-forming toxins. This study contributes to understanding the role of the multifaceted c-Jun proto-oncoprotein in cell response to bacterial pore-forming toxins, positioning it as a relevant component of the complex early machinery mounted to deal with staphylococcal infections.

Asunto(s)

Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/toxicidad , Células Epiteliales/efectos de los fármacos , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/toxicidad , Pulmón/efectos de los fármacos , Proteínas Proto-Oncogénicas c-jun/metabolismo , Células A549 , Anexina A5/farmacología , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Perforina , Fosforilación , Propidio/farmacología , Complejo de la Endopetidasa Proteasomal/metabolismo , Transducción de Señal , Staphylococcus aureus/metabolismo , Vibrio cholerae/metabolismo

RESUMEN

A correction to this article has been published and is linked from the HTML version of this paper. The error has not been fixed in the paper.

RESUMEN

Chlamydia trachomatis is the most prevalent sexually transmitted bacterial infection. However, whether Chlamydia trachomatis has a negative impact on sperm quality and male fertility is still controversial. Herein, we report the effects on sperm quality of the in vitro exposure of spermatozoa to Chlamydia trachomatis, and also the effects of male genital infection on male fertility using an animal model. Human and mouse sperm were obtained from healthy donors and cauda epididimys from C57BL/6 mice, respectively. Highly motile human or mouse spermatozoa were in vitro exposed to C. trachomatis (serovar E or LGV) or C. muridarum, respectively. Then, sperm quality parameters were analyzed. Moreover, male fertility of Chlamydia muridarum infected male C57BL/6 mice was assessed. Human or murine sperm in vitro exposed to increasing bacterial concentrations or soluble factors from C. trachomatis or C. muridarum, respectively, did not show differences in sperm motility and viability, apoptosis, mitochondrial membrane potential, DNA fragmentation, ROS production and lipid peroxidation levels, when compared with control sperm (p > 0.05). Moreover, no differences in fertility parameters (potency, fecundity, fertility index, pre- and post-implantation loss) were observed between control and infected males. In conclusion, our results indicate that Chlamydia spp. neither directly exerts deleterious effects on spermatozoa nor impairs male fertility.

Asunto(s)

Infecciones por Chlamydia/complicaciones , Infecciones por Chlamydia/patología , Chlamydia trachomatis/patogenicidad , Fertilidad , Infecciones del Sistema Genital/complicaciones , Infecciones del Sistema Genital/patología , Espermatozoides/fisiología , Animales , Movimiento Celular , Supervivencia Celular , Chlamydia muridarum/patogenicidad , Modelos Animales de Enfermedad , Humanos , Peroxidación de Lípido , Masculino , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno/metabolismo

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) burden is increasing worldwide in hospitals [healthcare-associated (HA)-MRSA] and in communities [community-associated (CA)-MRSA]. However, the impact of CA-MRSA within hospitals remains limited, particularly in Latin America. A countrywide representative survey of S. aureus infections was performed in Argentina by analyzing 591 clinical isolates from 66 hospitals in a prospective cross-sectional, multicenter study (Nov-2009). This work involved healthcare-onset infections-(HAHO, >48 hospitalization hours) and community-onset (CO) infections [including both, infections (HACO) in patients with healthcare-associated risk-factors (HRFs) and infections (CACO) in those without HRFs]. MRSA strains were genetically typed as CA-MRSA and HA-MRSA genotypes (CA-MRSAG and HA-MRSAG) by SCCmec- and spa-typing, PFGE, MLST and virulence genes profile by PCR. Considering all isolates, 63% were from CO-infections and 55% were MRSA [39% CA-MRSAG and 16% HA-MRSAG]. A significantly higher MRSA proportion among CO- than HAHO-S. aureus infections was detected (58% vs 49%); mainly in children (62% vs 43%). The CA-MRSAG/HA-MRSAG have accounted for 16%/33% of HAHO-, 39%/13% of HACO- and 60.5%/0% of CACO-infections. Regarding the epidemiological associations identified in multivariate models for patients with healthcare-onset CA-MRSAG infections, CA-MRSAG behave like HA-MRSAG within hospitals but children were the highest risk group for healthcare-onset CA-MRSAG infections. Most CA-MRSAG belonged to two major clones: PFGE-type N-ST30-SCCmecIVc-t019-PVL(+) and PFGE-type I-ST5-IV-SCCmecIVa-t311-PVL(+) (45% each). The ST5-IV-PVL(+)/ST30-IV-PVL(+) clones have caused 31%/33% of all infections, 20%/4% of HAHO-, 43%/23% of HACO- and 35%/60% of CACO- infections, with significant differences by age groups (children/adults) and geographical regions. Importantly, an isolate belonging to USA300-0114-(ST8-SCCmecIVa-spat008-PVL(+)-ACME(+)) was detected for the first time in Argentina. Most of HA-MRSAG (66%) were related to the Cordobes/Chilean clone-(PFGE-type A-ST5-SCCmecI-t149) causing 18% of all infections (47% of HAHO- and 13% of HACO-infections). Results strongly suggest that the CA-MRSA clone ST5-IV-PVL(+) has begun to spread within hospitals, replacing the traditional Cordobes/Chilean-HA-MRSA clone ST5-I-PVL(-), mainly in children. Importantly, a growing MRSA reservoir in the community was associated with spreading of two CA-MRSA clones: ST5-IV-PVL(+), mainly in children with HRFs, and ST30-IV-PVL(+) in adults without HRFs. This is the first nationwide study in Argentina providing information about the molecular and clinical epidemiology of CA-MRSA, particularly within hospitals, which is essential for designing effective control measures in this country and worldwide.

Asunto(s)

Infecciones Comunitarias Adquiridas/microbiología , Infección Hospitalaria/microbiología , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Argentina , Niño , Preescolar , Análisis por Conglomerados , Estudios Transversales , Femenino , Genotipo , Hospitales , Humanos , Lactante , Recién Nacido , Masculino , Staphylococcus aureus Resistente a Meticilina/genética , Persona de Mediana Edad , Tipificación Molecular , Estudios Prospectivos , Factores de Virulencia/genética , Adulto Joven

RESUMEN

Epidemiological surveillance for community-associated methicillin-resistant Staphylococcus aureus revealed prevalences of 33% and 13% in pediatric and adult patients, respectively, in Cordoba, Argentina, in 2005. This study describes for the first time the emergence and dissemination of the sequence type 5 (ST5) lineage as the most prevalent clone (89%) (pulsed-field gel electrophoresis type I-ST5-staphylococcal cassette chromosome type IVa-spa type 311) harboring the Panton-Valentine leukocidin and enterotoxin A genes.

Asunto(s)

Toxinas Bacterianas/biosíntesis , Infecciones Comunitarias Adquiridas/microbiología , Exotoxinas/biosíntesis , Leucocidinas/biosíntesis , Resistencia a la Meticilina , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Argentina/epidemiología , Técnicas de Tipificación Bacteriana , Niño , Preescolar , Análisis por Conglomerados , Infecciones Comunitarias Adquiridas/epidemiología , Infección Hospitalaria/microbiología , Dermatoglifia del ADN , ADN Bacteriano/genética , Electroforesis en Gel de Campo Pulsado , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/clasificación

RESUMEN

Vibrio cholerae is the causative agent of cholera in humans. In addition to the criticalvirulence factors cholera toxin and toxin coregulated pilus, V. cholerae secretes V.cholerae cytolysin (VCC), a pore-forming exotoxin able to induce cell lysis and extensivevacuolation. We have shown that this vacuolation is related to the activation of autophagyin response to VCC action. Furthermore, we found that the autophagic pathway wasrequired to protect cells upon VCC intoxication. Based on additional data presented here,we propose a model aimed to explain the mechanism of cell protection. We postulatethat VCC-induced autophagic vacuoles, which display features of multivesicular bodies and enclose the toxin, are implicated in cell defense through VCC degradation involvingfusion with lysosomes.

Asunto(s)

Autofagia/fisiología , Glicoproteínas de Membrana/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Vibrio cholerae/fisiología , Animales , Células CHO , Células CACO-2 , Supervivencia Celular/fisiología , Cricetinae , Cricetulus , Humanos , Lisosomas/metabolismo , Glicoproteínas de Membrana/ultraestructura , Modelos Biológicos , Perforina , Proteínas Citotóxicas Formadoras de Poros/ultraestructura , Vacuolas/metabolismo , Vacuolas/ultraestructura , Vibrio cholerae/patogenicidad

RESUMEN

Since 1999, a new, epidemic, methicillin-resistant Staphylococcus aureus (MRSA) strain, named the "Cordobes clone," has emerged in Argentina and coexists with the pandemic Brazilian clone. The purpose of this study was to determine the stability over time of the new clone and to investigate its evolutionary relationship with epidemic international MRSA lineages and with other MRSA and methicillin-susceptible S. aureus (MSSA) major clones distributed in this region. One hundred three MRSA isolates recovered in 2001 from Cordoba, Argentina, hospitals and 31 MSSA strains collected from 1999 to 2002 were analyzed by their antibiotic resistance patterns, phage typing, and pulsed-field gel electrophoresis. Additionally, representative members of most MRSA defined genotypes (A, B, C, E, K, and I) were characterized by multilocus sequence typing (MLST) and spaA and SCCmec typing. The most prevalent MSSA pulsotypes were also analyzed by MLST. Our results support the displacement of the Brazilian clone (sequence type [ST] 239, spaA type WGKAOMQ, SCCmec type IIIA) by the Cordobes clone (ST5, spaA type TIMEMDMGMGMK, SCCmec type I) in the hospital environment. MRSA and MSSA isolates shared only ST5. The data support the origin of the Cordobes clone as a member of a lineage that includes the pediatric and New York/Japan international clones and that is genetically related to the British EMRSA-3 strain. Interestingly, the pediatric clone, isolated from most community-acquired infections in Cordoba, was characterized by ST100, a single-locus variant of ST5 and a new variant of SCCmec type related to SCCmec type IVc.

Asunto(s)

Infecciones Comunitarias Adquiridas/microbiología , Infección Hospitalaria/microbiología , Evolución Molecular , Resistencia a la Meticilina/genética , Staphylococcus aureus/genética , Antibacterianos/farmacología , Argentina/epidemiología , Técnicas de Tipificación Bacteriana , Hospitales , Humanos , Meticilina/farmacología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación

RESUMEN

The gene bla(CARB-9) was located in the Vibrio cholerae super-integron, but in a different location relative to bla(CARB-7). CARB-9 (pI 5.2) conferred beta-lactam MICs four to eight times lower than those conferred by CARB-7, differing at Ambler's positions V97I, L124F, and T228K. Comparison of the genetic environments of all reported bla(CARB) genes indicated that the CARB enzymes constitute a family of cassette-encoded beta-lactamases.

Asunto(s)

Penicilinasa/genética , Vibrio cholerae/enzimología , Vibrio cholerae/genética , beta-Lactamasas/genética , Secuencia de Aminoácidos , Argentina , Datos de Secuencia Molecular , Penicilinasa/clasificación , Secuencias Repetitivas de Aminoácido , beta-Lactamasas/clasificación , beta-Lactamasas/metabolismo