Serological Evidence of Borrelia Burgdorferi Infection in Mexican Patients with Facial Palsy.

BACKGROUND: Facial palsy is the most frequent manifestation of neuroborreliosis in the United States, Europe, and Asia, whereas in Mexico, its frequency is unknown. OBJECTIVE: We aimed to determine the frequency of Borrelia spp. infection in patients with acute facial palsy in Mexico. MATERIALS AND METHODS: In this cross-sectional, referral hospital-based survey, 191 patients with facial palsy were selected and clinical and epidemiologic data recorded. IgM and IgG serum antibodies to Borrelia burgdorferi were tested by enzyme-linked immunosorbent assay (ELISA) and confirmed by Western-Blot (WB). IgM and IgG antibodies against the herpes viruses HSV-1, HSV-2, cytomegalovirus, and Epstein-Barr virus were tested by ELISA. RESULTS: 71 patients (37%) tested positive by ELISA to either Borrelia spp. or the herpes viruses. Of 25 patients (13%) who tested positive for B. burgdorferi by ELISA, 23 (12%) were confirmed by WB; 14 had IgM and 9 had IgG antibodies. Among the 14 IgM-WB positive patients, two cases recognized antigens of B. burgdorferi sensu stricto (s.s.), 10 of Borrelia garinii and 2 of B. afzelii, whereas all 9 IgG-WB positive were reactive against B. burgdorferi s.s. 14 patients had facial palsy in addition to other clinical data compatible with Lyme borreliosis. Patients infected with B. burgdorferi s.s. had a longer recovery time and a significantly higher risk (odds ratio 4.4, 95% confidence interval 1.5-12.9) of recurrent facial palsy than patients infected with other Borrelia genospecies. CONCLUSIONS: Borrelia infection is frequent in facial palsy patients in Mexico, with B. burgdorferi s.s. and B. garinii being the most frequent causative species.

In vivo expression of Helicobacter pylori virulence genes in patients with gastritis, ulcer, and gastric cancer.

The best-studied Helicobacter pylori virulence factor associated with development of peptic ulcer disease or gastric cancer (GC) rather than asymptomatic nonatrophic gastritis (NAG) is the cag pathogenicity island (cagPAI), which encodes a type IV secretion system (T4SS) that injects the CagA oncoprotein into host epithelial cells. Here we used real-time reverse transcription-PCR (RT-PCR) to measure the in vivo expression of genes on the cagPAI and of other virulence genes in patients with NAG, duodenal ulcer (DU), or GC. In vivo expression of H. pylori virulence genes was greater overall in gastric biopsy specimens of patients with GC than in those of patients with NAG or DU. However, since in vitro expression of cagA was not greater in H. pylori strains from patients with GC than in those from patients with NAG or DU, increased expression in GC in vivo is likely a result of environmental conditions in the gastric mucosa, though it may in turn cause more severe pathology. Increased expression of virulence genes in GC may represent a stress response to elevated pH or other environmental conditions in the stomach of patients with GC, which may be less hospitable to H. pylori colonization than the acidic environment in patients with NAG or DU.

About possible medications to treat SARS-CoV-2 infection, which causes COVID-19: is there any hope? / Sobre posibles medicamentos para tratar la infección por SARS-CoV-2, causante de la COVID-19: ¿hay alguna esperanza?

To date, there is no treatment for patients infected with SARS-CoV-2. Several studies are being carried out in several countries and some have yielded promising results; however, still no effective treatment has been identified to combat COVID-19, one of the most serious threats humanity has suffered in the last 100 years.

Hasta el día de hoy no se cuenta con un tratamiento para los pacientes infectados con SARS-CoV-2. Se están llevando a cabo estudios en varios países y algunos han arrojado resultados prometedores; sin embargo, aún no se ha logrado identificar un tratamiento efectivo para combatir la COVID-19, una de las amenazas más serias que ha sufrido la humanidad en los últimos 100 años.

[What is the origin of SARS-CoV-2?] / ¿Cuál es el origen del SARS-CoV-2?

Every time a pandemic occurs, dozens of theories emerge to attribute the origin of the event to different facts. The COVID-19 pandemic that has hit virtually all the globe has been no exception. What is known so far about the origin of the virus that causes COVID 19? The first investigations on the origin of this disease have determined that it is a new type of virus, the origin of which is most likely zoonotic.

Cada vez que se produce una pandemia surgen decenas de teorías que atribuyen el origen de los acontecimientos a distintos hechos. La pandemia de COVID-19 que ha azotado a prácticamente todo el mundo no ha sido la excepción. ¿Qué se sabe hasta ahora sobre el origen del virus causante de COVID-19? Las primeras investigaciones sobre el origen de esta enfermedad han determinado que se trata de un nuevo tipo de virus, cuyo origen muy probablemente sea de tipo zoonótico.

Expression changes of BIK in breast cancer tissues of different histological subtypes.

OBJECTIVE: The objective of the study was to determine the expression levels of BIK in breast cancer (BC) tissues of different histological subtype and to delve into the participation of BIK in this type of cancer. MATERIALS AND METHODS: BIK and p-BIK (the phosphorylated form) protein expressions were tested by immunohistochemistry in BC tissue microarrays (Tumoral [n = 90] and adjacent [n = 40] tissues). RESULTS: The data revealed an overexpression of BIK in invasive ductal (Grades I, IIA, and IIB) and in lobular (Grades IIA and IIB) carcinomas compared to their respective adjacent tissues. By contrast, canalicular carcinoma (Grades I and IIB) and phyllodes tumors had very low expression levels of BIK. Only levels of p-BIK were shown to be increased in invasive ductal carcinoma (Grades I, IIA, and IIB). Meanwhile, quantitative polymerase chain reaction analysis showed lower BIK levels in MCF-10A and MCF-7 cells than in MDA-MB-231 and human mammary epithelial cells. In agreement with this, BIK protein was shown to be overexpressed in MDA-MB 231 relative to MCF-7 cells. CONCLUSIONS: Our results showed an association between BIK expression and the BC tumor subtype under study, which could be related to different BIK functions in the BC subtypes.

OBJETIVO: Determinar el grado de expresión de BIK en tejidos de cáncer de mama de diferente subtipo histológico para ahondar en la participación de BIK en este tipo de cancer. MÉTODO: Por medio de inmunohistoquímica se determinó la expresión de BIK y de su forma fosforilada (p-BIK) en microarreglos de tejidos (tumores [n = 90] y tejidos adyacentes [n = 40]) y líneas celulares. RESULTADOS: Los datos mostraron una sobreexpresión de BIK en los carcinomas de tipo ductal invasivo (grados I, IIA y IIB) y lobular (grados IIA y IIB) con respecto a sus tejidos adyacentes respectivos. En contraste, el carcinoma canalicular (grados I y IIB) y los tumores filoides mostraron una baja expresión de BIK en relación con sus tejidos adyacentes respectivos. El análisis de la qPCR mostró una menor expresión de BIK en las células MCF-10A y MCF-7 en comparación con las células MDA-MB-231 y HMEC. En concordancia con esto, la expresión proteica de BIK fue mayor en las células MDA-MB 231 que en las células MCF-7. CONCLUSIÓN: Nuestros resultados mostraron una asociación entre la expresión de BIK y el subtipo tumoral en estudio, lo cual sugiere una función diferencial de BIK en el cáncer de mama.

Immunological markers and Helicobacter pylori in patients with stomach cancer: Expression and correlation.

Programmed death-ligand 1 (PD-L1) and ICOS-L (also referred to as B7 homolog 1 and 2, respectively) modulate the immune inflammatory response. The aim of the present study was to examine the expression levels of these inflammatory mediators in two groups of patients with an Helicobacter pylori (H. pylori) infection; patients with and without gastric cancer. The association between bacterial virulence factors, CagA and VacA, was also examined, as well as their correlation with the inflammatory profile. Endoscopy analysis indicated that 18 patients suffered from cancer and 28 patients suffered from other gastric pathologies. PCR and reverse transcription-quantitative PCR were used to analyze gastric biopsies and determine the expression levels of the inflammatory modulators PD-L1 and ICOS-L, transcription factors, cytokines and other genes associated with inflammation and pathogenicity. All 46 patients were determined positive for markers of H. pylori. Patients with stomach cancer had lower levels of ICOS-L (P<0.05) and GATA3 (P<0.01), a negative correlation between CagA and IL-17 (P<0.05), a positive correlation between CagA and IL-10 (P<0.05), a negative correlation between vacA-m1 and retinoid orphan receptor γt (RORγt) (P<0.001), and a positive correlation between RORγt and ICOS-L (P<0.001). The reduced levels of ICOS-L and GATA3 along with the negative correlation between CagA and IL-17, and between vacA-m1 and RORγt were all associated with an increased risk of gastric cancer in the present cohort.

Resource utilization and costs of treating severe rotavirus diarrhea in young Mexican children from the health care provider perspective.

BACKGROUND: Rotavirus is the most common cause of severe diarrhea in infants. The economic costs of treating severe rotavirus can be quite significant and are important to include in any evaluation of prevention programs. The aim of this study was to determine utilization of health care resources and costs incurred due to severe diarrhea associated with rotavirus infection in Mexican children < 5 years of age. MATERIAL AND METHODS: The costs of rotavirus infection evaluated in this observational study consisted of hospital, emergency room care and out-patient visit expenses at three hospitals of the Mexican Institute of Social Security throughout 1999-2000. Service costs were estimated from costs of care for rotavirus versus non-rotavirus diarrhea obtained through a follow-up study data of 383 children and administrative records. RESULTS: Diarrhea cases due to rotavirus infection comprised 36% of the sample. Participants with rotavirus diarrhea spent an average of 3.2 days in the hospital, 5.9 hours in the emergency room, and had 1.3 visits to an outpatient physician's office. Some differences in the consumption of health care were found between rotavirus and non-rotavirus diarrhea cases, although the mean costs of rotavirus and nonrotavirus cases were not significantly different. The mean cost per case of severe rotavirus diarrhea was estimated to be US $936. The total cost of treating severe rotavirus diarrhea, including 5,955 rotavirus hospitalizations for 2004, was estimated at US $5.5 million. CONCLUSION: Health care costs due to treatment for severe rotavirus diarrhea are a significant economic burden to the Mexican Social Security system.

Effect of the flavonoid quercetin on inflammation and lipid peroxidation induced by Helicobacter pylori in gastric mucosa of guinea pig.

BACKGROUND: Helicobacter pylori infection induces an inflammatory response in the gastric mucosa. Activation of polymorphonuclear leukocytes can produce oxidative damage to gastric tissue through intermediary radicals of oxygen and nitrogen. Vegetable extracts containing polyphenols of the flavonoid family have antibacterial activity, and the flavonoid quercetin possesses anti-H. pylori activity in vitro. The aim of this study was to analyze the effect of oral administration of pure quercetin on inflammation and lipid peroxidation induced by H. pylori in the gastric mucosa of the guinea pig. METHODS: Sixty days after oral infection with H. pylori guinea pigs received 200 mg/kg of quercetin daily by mouth for 15 days. The infiltration index of inflammatory cells and bacterial density in both the pyloric antrum and corpus were histologically determined by myeloperoxidase histochemistry, hematoxylin-eosin, and modified Giemsa stains. The lipid hydroperoxide content was assessed by the orange xylenol spectrophotometric method. RESULTS: Quercetin significantly reduced the infiltration index of mononuclear cell and bacterial colonization in the pyloric antrum and corpus. In the antrum of infected quercetin-treated animals, a significant diminution of neutrophil leukocyte infiltration was observed compared with the infected nonquercetin-treated animals. In the antrum, the lipid hydroperoxide concentration was significantly decreased in infected animals treated with quercetin, whereas in the corpus no significant differences were observed. CONCLUSIONS: Our results indicate that in vivo oral quercetin administration decreases H. pylori infection in the gastric mucosa and reduces both the inflammatory response and lipid peroxidation.

Helicobacter pylori-CagA seropositivity and nitrite and ascorbic acid food intake as predictors for gastric cancer.

A hospital-based case-control study was carried out between 1994 and 1996 to evaluate the risk of gastric cancer (GC) according to Helicobacter pylori-CagA (+) seropositivity, nitrite and ascorbic acid intake. Three geographical areas of Mexico were selected on the basis of their contrasting dietary patterns and H. pylori seroprevalence. Nitrite and ascorbic acid consumption were estimated by interview among 211 cases and 454 matched controls. Serum antibodies against IgG H. pylori and CagA were detected by immunosorbent assays. The adjusted risk for GC was significantly higher among CagA+ subjects compared with those that were CagA negative (Odds Ratio (OR)=2.04 95% Confidence Interval (CI) 1.37-3.02 P for trend P < 0.001), this effect remained significant among diffuse GC cases (OR 2.05 95% CI 1.25-3-36). No significant effects due to nitrite and ascorbic consumption or interactions of these nutrients with CagA seropositivity were detected. Seropositivity to H. pylori CagA+ strains may be an independent factor for diffuse GC in Mexico.

Análisis in silico de proteínas potencialmente involucradas en la biogénesis de fimbrias en Helicobacter pylori / In silico analysis of proteins potentially involved in fimbrial biogenesis in Helicobacter pylori

Introducción. La colonización e infección crónica por Helicobacter pylori es el factor de mayor contribución al desarrollo de cáncer gástrico. Se ha descrito un gran repertorio de adhesinas que contribuyen a la adaptación específica de la bacteria al nicho gástrico y, para H. pylori , al igual que en otras bacterias patógenas, la formación de biopelícula es fundamental en la supervivencia a ambientes no favorables. Las fimbrias o pili tipo IV son responsables de la adhesión de diversas bacterias patógenas ( Escherichia coli , Pseudomonas aeruginosa y Vibrio cholerae) a distintas superficies. El objetivo de este trabajo fue identificar y analizar genes que pudieran codificar para proteínas involucradas en la biogénesis de fimbrias en H. pylori y caracterizar su expresión durante la formación de biopelícula. Métodos. Se emplearon herramientas bioinformáticas y moleculares, tales como la base de datos del NCBI para la búsqueda de secuencias de proteínas relacionadas con la biogénesis de fimbrias, así como la herramienta de PSI BLAST. Los alineamientos múltiples se realizaron con el programa T-COFFEE y HMMER. La predicción de las estructuras secundarias se realizó con ANTHEPROT y las estructuras terciarias se predijeron con el programa I-TASSER. Resultados. Se identificaron dos homólogos, jhp0257 y HP0272, de la proteína PilN de Campylobacter rectus y Xilella fastidiosa , la cual es parte de la maquinaria del ensamble de la fimbria tipo IV. Asimismo, las proteínas jhp0887 y HP0953 presentaron homología a nivel del péptido señal de PilA de P. aeruginosa , y la proteína HP0953 se sobreexpresó durante la formación de la biopelícula. Conclusiones. H. pylori posee proteínas homólogas a las proteínas de familias fimbriales, específicamente PilN y PilA, que ensamblan fimbria tipo IV en otras bacterias. Esta última tiene un nivel de expresión mayor durante la etapa inicial del proceso de formación de biopelícula.

Background. Colonization and chronic infection with Helicobacter pylori is the major contributing factor to the development of gastric cancer. A large repertoire of adhesins has been described that contribute to the adaptation of bacteria to a specific gastric niche. As in other pathogenic bacteria, H. pylori biofilm formation is central to survival on unfavorable environments. Type IV pili or fimbriae are responsible for the adhesion of many pathogenic bacteria (e.g., Escherichia coli, Pseudomonas aeruginosa and Vibrio cholerae ) to various surfaces. The aim of this study was to identify and analyze genes that might encode proteins involved in the biogenesis of fimbriae on H. pylori and characterize their expression during biofilm formation. Methods. PSI BLAST, bioinformatics and molecular tools were used as well as the NCBI database search for sequences related to protein biogenesis of fimbriae. Multiple alignments were performed using the HMMer and T-COFFEE programs. The secondary structure prediction was performed with ANTHEPROT and the tertiary structures were predicted with the I-Tasser. Results. We identified two counterparts-jhp0257 and HP0272-from protein of Campylobacter rectus and PilN Xilella fastidiosa , which is part of the machinery of assembly type IV fimbria. Similarly, proteins jhp0887 and HP0953 show homology from peptide PilA level of P. aeruginosa , and the HP0953 protein is overexpressed during the formation of the biofilm. Conclusions. H. pylori possesses proteins homologous to fimbrial protein families, specifically PilN and PilA, which join type IV fimbriae in other bacteria. The latter has a higher expression level during the initial stage of the formation of biofilm.

Del proteoma humano a la medicina transfuncional personalizada / From human proteome to cross-functional personalized medicine

Actualmente, se ha dado una revolución tecnológica en la medicina personalizada. En esta nueva fase de la proteómica, la prioridad es la apreciación de los valores y virtudes del ser humano. Por esto, no debemos olvidar que las dos razones principales de la medicina personalizada son el reconocimiento de la dignidad de la persona y el diagnóstico y el tratamiento hecho a la medida para cada paciente, se deben tomar en cuenta el trasfondo social y el entorno ambiental a la par de los genes y las proteínas.

Personalized medicine has led the technological revolution in proteomics into a new phase where appreciation of the values and virtues of the human being are paramount. Thus we must not forget that the two main reason for personalized medicine are both acknowledgment of the person's dignity and a tailored diagnosis and treatment of each patient, taking into account not only genes and proteins but also the person's social background and environment.

[Exposure to group B Streptococcus among Mexican women in reproductive age]. / Exposición a Estreptococo del grupo B en mujeres mexicanas en edad reproductiva.

OBJECTIVE: To assess the prevalence of IgG antibodies against Group B streptococci (GBS) among women of reproductive age in Mexico. MATERIAL AND METHODS: Serum specimens were drawn from 15 to 40 year-old women, representative of all regions and socioeconomic levels of the country. The sample was randomly selected from Banco Nacional de Sueros (National Sera Bank); serum samples were collected during a national seroepidemiologic survey conducted in 1987-1988. The assays for standardization and for evaluation of seroprevalence were carried out at the Hospital de Pediatría del Centro Médico Nacional Siglo XXI (Children's Hospital) Instituto Mexicano del Seguro Social (IMSS) (Mexican Institute of Social Security) from January to November 1995. IgG antibodies against group B antigen were studied with an enzyme-linked immunosorbent assay (ELISA) developed in our lab. Group B antigen was produced and purified from the reference strain GBS 110. RESULTS: A total of 2669 serum samples were studied; 2405 were positive to anti-group B antigen IgG antibodies, for a seroprevalence of 90.2%. No differences in prevalence were found among the different age groups or among the different states of the country. CONCLUSIONS: The high seroprevalence of antibodies against GBS suggests that young women in Mexico are commonly exposed to GBS infection.

Exposición a Estreptococo del grupo B en mujeres mexicanas en edad reproductiva / Exposure to group B Streptococcus among Mexican women in reproductive age

OBJECTIVE: To assess the prevalence of IgG antibodies against Group B streptococci (GBS) among women of reproductive age in Mexico. MATERIAL AND METHODS: Serum specimens were drawn from 15 to 40 year-old women, representative of all regions and socioeconomic levels of the country. The sample was randomly selected from Banco Nacional de Sueros (National Sera Bank); serum samples were collected during a national seroepidemiologic survey conducted in 1987-1988. The assays for standardization and for evaluation of seroprevalence were carried out at the Hospital de PediatrÝa del Centro MÚdico Nacional Siglo XXI (Children's Hospital) Instituto Mexicano del Seguro Social (IMSS) (Mexican Institute of Social Security) from January to November 1995. IgG antibodies against group B antigen were studied with an enzyme-linked immunosorbent assay (ELISA) developed in our lab. Group B antigen was produced and purified from the reference strain GBS 110. RESULTS: A total of 2669 serum samples were studied; 2405 were positive to anti-group B antigen IgG antibodies, for a seroprevalence of 90.2. No differences in prevalence were found among the different age groups or among the different states of the country. CONCLUSIONS: The high seroprevalence of antibodies against GBS suggests that young women in Mexico are commonly exposed to GBS infection.

Producción de toxinas A y B por cepas de Clostridium difficile aisladas de lactantes y adultos / Production of A and B toxins by Clostridium difficile strains isolated from infants and adults

En este estudio se pretendió definir si existe alguna diferencia en el potencial toxígeno de cepas de Clostridium difficile aisladas de lactantes comparadas con cepas aisladas de adultos. Se analizan las cepas aisladas para producción de toxina a utilizando la prueba de asa intestinal de conejo y un ensayo inmunoenzimático, y para la toxína B, ensayos en cultivo de tejidos. Se encontró que las cepas toxígenas fueron menos frecuentes entre los aislamientos de lactantes (6 de 16) que entre los aislamientos de adultos (5 de 6). Estos resultados sugieren que las cepas no productoras, así como las poco productoras, son más frecuentes entre los lactantes

Posible producción de dos citotoxinas por una cepa de Escherichia coli / Possible production of 2 cytotoxins by a strain of Escherichia coli

Las citotoxinas VT y "Shiga-like" juegan un papel importante en la diarrea provocada por algunas cepas enteropatógenas de E. coli. Existe confusión acerca de que si estas dos actividades se deben a una sola toxina. Se empleó la cepa H30 de E. coli perteneciente al grupo 026 en la cual se describieron las dos actividades mediante una cinética de crecimiento tomando muestras a diferentes intervalos para observar su correlación con la actividad citotóxica, tanto en sobrenadante de cultivo como en lisado celular, probándola en cultivos de tejidos de células Hela y fibroblastos de ratón. Encontramos que en el sobrenadante la actividad citotóxica aparece en la fase logarítmica de crecimiento, mientras que la actividad en el lisado aparece hasta la fase estacionaria. Pensamos que se trata de dos citotoxinas diferentes producidas por la misma cepa, aunque es necesario profundizar en esta línea de trabajo

Secretion antigens of mycobacterium tuberculosis: A comparison between a reference strain and seven wild isolates

Background. This study was carried out with the aim of detecting possible differences between proteins secreted by fresh wild isolates of Mycrobacterium tuberculosis and from a reference strain of this microorganism, H37Rv TMCC 102. Materials and Methods. This reference strain of M tuberculosis has been in our laboratory for over 10 years, where it has been maintained by serial subcultures in PBY and Lo-wenstein-Jensen media. Patterns of protein secretion and recognition by sera derive from both tuberculosis patients and normal individuals were analysed by electrophoresis and Western blotting. Results. No major qualitative differences were observed among the several strains studied with respect to protein patterns or recognition of these proteins by test sera. Normal sera were found to react with almost all antigens recognized by tuberculosis sera, but with less intensity. However, a small protein of 14.5 kDa, secreted by both the wild and reference strain of M. tuberculosis, was recognized by 32 of the 40 tuberculous patient sera tested (80 percent), and was not recognized by any of the 40 serum samples derived from healthy individuals. Conclusions. This small protein seems to be a potentially important antigen for the serological diagnosis of tuberculosis and/or for use in the follow-up patients who received treatment