Disturbances in the IgG Antibody Profile in HIV-Exposed Uninfected Infants Associated with Maternal Factors.

Over the last 20 years, the incidence of vertical HIV transmission has decreased from 25%-42% to less than 1%. Although there are no signs of infection, the health of HIV-exposed uninfected (HEU) infants is notoriously affected during the first months of life, with opportunistic infections being the most common disease. Some studies have reported effects on the vertical transfer of antibodies, but little is known about the subclass distribution of these antibodies. We proposed to evaluate the total IgG concentration and its subclasses in HIV+ mothers and HEU pairs and to determine which maternal factors condition their levels. In this study, plasma from 69 HEU newborns, their mothers, and 71 control pairs was quantified via immunoassays for each IgG isotype. Furthermore, we followed the antibody profile of HEUs throughout the first year of life. We showed that mothers present an antibody profile characterized by high concentrations of IgG1 and IgG3 but reduced IgG2, and HEU infants are born with an IgG subclass profile similar to that of their maternal pair. Interestingly, this passively transferred profile could remain influenced even during their own antibody production in HEU infants, depending on maternal conditions such as CD4+ T-cell counts and maternal antiretroviral treatment. Our findings indicate that HEU infants exhibit an altered IgG subclass profile influenced by maternal factors, potentially contributing to their increased susceptibility to infections.

Genotipificación del virus del papiloma humano en mujeres embarazadas VPH positivas / Genotyping of human papillomavirus in HPV-positive pregnant women

Resumen Antecedentes: Las embarazadas infectadas por el virus del papiloma humano presentan condiciones médicas que influyen en el curso de la enfermedad y pueden potenciar la posibilidad de transmisión vertical. Objetivo: Identificar los genotipos del virus del papiloma humano más frecuentes en mujeres embarazadas. Método: Estudio retrospectivo, observacional y descriptivo. Se emplearon muestras de raspado cervical. La extracción de material genético se hizo por la técnica de fenol-cloroformo y se amplificó empleando iniciadores universales MY09/MY11. Las muestras positivas se genotipificaron con un kit que detecta 37 genotipos diferentes. Resultados: Se identificaron 341 genotipos. Los más frecuentes fueron 16 (10.3%), 52 (8.8%) y 59 (8.6%). En el 75.9% la detección fue con un genotipo y en el 42.7% se detectaron infecciones múltiples. Conclusiones: Es sabido que la infección por virus del papiloma humano en mujeres embarazadas raramente evolucionará a lesiones invasivas. Se deberán considerar tanto las posibles complicaciones obstétricas a corto y largo plazo, así como las posibles repercusiones en la salud del recién nacido. La detección elevada del genotipo 16 sugiere un seguimiento estrecho para considerar un abordaje óptimo posterior a la gestación.

Abstract Background: Pregnant women infected with human papillomavirus have medical conditions that influence the course of the disease and can increase the possibility of vertical transmission. Objective: To identify the most common human papillomavirus genotypes in pregnant women. Method: Retrospective, observational and descriptive study. Cervical scraping samples were used. The extraction of genetic material was done by the phenol-chloroform technique and was amplified using universal primers MY09/MY11. Positive samples were genotyped with a kit that detects 37 different genotypes. Results: Three hundred forty-one genotypes were identified. The most frequent were 16 (10.3%), 52 (8.8%), and 59 (8.6%). In 75.9% the detection was with one genotype and in 42.7% multiple infections were detected. Conclusions: It is known that human papillomavirus infection in pregnant women will rarely evolve to invasive lesions. Both possible short- and long-term obstetric complications, as well as possible repercussions on the health of the newborn, should be considered. The high detection of genotype 16 suggests close follow-up to consider an optimal post-pregnancy approach.

Effect of Oropharyngeal Administration of Colostrum in Premature Newborns ≤32 Weeks of Gestation on the Immune Response and Neonatal Morbidity: A Double-Blind Randomized Clinical Trial.

Introduction: The mother's colostrum carries immunological components, such as cytokines and immunoglobulins (Igs), derived from the maternal circulation with bacteriostatic properties. Objective: The objective of this study was to evaluate the effect of oropharyngeal administration of colostrum (OPAC) vs. placebo in the first 4 days of life in premature newborns ≤32 weeks of gestation on serum Ig concentration, neonatal morbidity, and total days of hospitalization. Hypothesis: The OPAC increases serum Igs and decreases morbidity and total days of hospitalization. Materials and Methods: A double-blind randomized controlled trial was carried out. Participants were randomly assigned to one of the two groups, namely, group 1: placebo (P) (n = 50) and group 2: colostrum (C) (n = 46). A blood sample was obtained at baseline and 7 and 28 days of life to quantify immunoglobulin G (IgG), immunoglobulin A (IgA), and IgM. Results: The C group showed an increase in serum IgA on day 28 expressed as median and [interquartile range]; C: 25 [12-35] vs. P: 11 [8-18], p < 0.001. There were no significant differences in neonatal morbidity. Newborns in the colostrum group showed the completed enteral feeding earlier (days), C: 13.9 ± 7 vs. P: 17.4 ± 8.4, p < 0.04; they reached the birth weight earlier, C: 10.9 ± 2.8 vs. P: 12.9 ± 4, p < 0.01, and had less days of hospitalization, C: 60.2 ± 33.8 vs. P: 77.2 ± 47.3, p < 0.04. Neonatal mortality was lower in the colostrum group than the placebo group 0% vs. 12%, respectively, without a statistical difference (p = 0.06). Conclusion: In premature newborns ≤32 weeks of gestation, the OPAC within 4 days after birth increases serum IgA concentration at day 28 compared to placebo. Similarly, OPAC decreased the days to complete enteral feeding and reach the birth weight and total days of hospitalization. Clinical Trial Registration: [https://clinicaltrials.gov/ct2/show/NCT03578341], identifier: [NCT03578341].

Impaired T helper cell responses in human immunodeficiency virus-exposed uninfected newborns.

INTRODUCTION: HIV-exposed uninfected (HEU) newborns suffer from higher risks of opportunistic infections during the first months of life compared to HIV-unexposed uninfected (HUU) newborns. Alterations in thymic mass, amounts of T helper (Th) cells, T-cell receptor diversity, and activation markers have been found in HEU newborns, suggesting alterations in T cell ontogeny and differentiation. However, little is known about the ability of these cells to produce specialized Th responses from CD4+ T cells. METHOD: To characterize the Th cell profile, we evaluated the frequency of Th1 (CD183+ CD194- CD196- /CXCR3+ CCR4- CCR6- ), Th2 (CD183- CD194+ CD196- /CXCR3- CCR4+ CCR6- ), Th17 (CD183- CD194+ CD196+ /CXCR3- CCR4+ CCR6+ ), and CD4+ CD25++ blood T-cell phenotypes in 50 HEU and 25 HUU newborns. Early activation markers on CD4+ T cells and the Th cytokine profile produced from mononuclear cells under polyclonal T cell stimulation were also studied. Additionally, we probed the ability of CD4+ T cells to differentiate into interferon (IFN)-γ-producing Th1 CD4+ T cells in vitro. RESULTS: Lower percentages of differentiated Th1 , Th2 , Th17, and CD4+ CD25++ T cells were found in blood from HEU newborns than in blood from HUU newborns. However, polyclonally stimulated Th cells showed a similar ability to express CD69 and CD279 but produced less secreted interleukin (IL)-2 and IL-4. Interestingly, under Th1 differentiation conditions, the percentages of CD4+ IFN-γ+ T cells and soluble IFN-γ were higher in HEU newborns than in HUU newborns. CONCLUSION: HEU neonates are born with reduced proportions of differentiated Th1 /Th2 /Th17 and CD4+ CD25++ T cells, but the intrinsic abilities of CD4+ T cells to acquire a Th1 profile are not affected by the adverse maternal milieu during development.

Utility of two DNA extraction methods using formalin-fixed paraffin-embedded tissues in identifying congenital cytomegalovirus infection by polymerase chain reaction.

Formalin-fixed paraffin-embedded (FFPE) tissues are a source of biological material for molecular studies; several methods to extract DNA from FFPE tissues have been reported. This process is challenging because of formaldehyde-induced cross-linking between proteins and DNA as well as molecule fragmentation when unbuffered formalin is used for fixation. Here, 2 methods for DNA extraction from FFPE tissues, based on a chelating resin and silica membrane columns, were modified and compared in their capacity to detect human cytomegalovirus (HCMV) in congenital infections. Both methods were tested on 121 samples of brain, lung, spleen, and liver derived from 36 deceased preterm newborns. Twelve patients were selected, and UL55 and UL75 HCMV genes were detected by polymerase chain reaction in 16/36 samples. These 2 methods represent a useful tool for DNA recovery from FFPE tissues and HCMV molecular identification with the advantage of low cost, minimal steps, minimal sample use, being solvent-free, and being easy to implement in the laboratory.

Characterization of CD127- CD25++ Treg from human colostrum.

PROBLEM: Breastfeeding's influence on the tolerance to environmental antigens is essential for short- and long-term homeostasis for children. Colostrum is rich in leucocytes, but it is unknown whether regulatory T cells (Treg) account for part of this cell population. METHOD OF STUDY: Frequencies of CD127-  CD25++ Treg and levels of immunoregulatory-associated cell markers were determined in colostrum and were compared with autologous blood cells. In addition, we evaluated whether the birth conditions can affect these features. RESULTS: Higher frequencies of CD127 - CD25++ Treg cells expressing Foxp3 and CD45RO were observed in the colostrum. The cells' CD25, CD152, CD279, and TGF-ß expression levels were greater than those in autologous blood cells. In addition, the CD279 and TGF-ß expressions of colostrum CD127-  CD25++ Treg cells were influenced by gestational age and delivery mode. CONCLUSION: The higher proportion of these cells with a function-associated phenotype may reflect certain tolerogenic effects of breastmilk on newborns and infants, contributing to immune system homeostasis.

Microbiological comparison of blood culture and amplification of 16S rDNA methods in combination with DGGE for detection of neonatal sepsis in blood samples.

It is estimated that 15% of all newborns admitted to the neonatal intensive care unit (NICU) for suspected sepsis receive multiple broad-spectrum antibiotics without pathogen identification. The gold standard for bacterial sepsis detection is blood culture, but the sensitivity of this method is very low. Recently, amplification and analysis of the 16S ribosomal DNA (rDNA) bacterial gene in combination with denaturing gradient gel electrophoresis (DGGE) has proven to be a useful approach for identifying bacteria that are difficult to isolate by standard culture methods. The main goal of this study was to compare two methods used to identify bacteria associated with neonatal sepsis: blood culture and broad range 16S rDNA-DGGE. Twenty-two blood samples were obtained from newborns with (n = 15) or without (n = 7) signs and symptoms of sepsis. Blood samples were screened to identify pathogenic bacteria with two different methods: (1) bacteriological culture and (2) amplification of the variable V3 region of 16S rDNA-DGGE. Blood culture analysis was positive in 40%, whereas 16S rDNA-DGGE was positive in 87% of neonatal sepsis cases. All 16S rDNA-DGGE positive samples were associated with some other signs of neonatal sepsis. CONCLUSION: Our study shows that the molecular approach with 16S rDNA-DGGE identifies twofold more pathogenic bacteria than bacteriological culture, including complex bacterial communities associated with the development of bacterial sepsis in neonates. What is Known: • Neonatal sepsis affects 2.3% of birth in the NICU with a high mortality risk. • Evidence supports the use of molecular methods as an alternative to blood culture for identification of bacterial associated neonatal sepsis. What is New: • The DGGE gel is a good methodological approach for the identification of bacterial in neonatal blood samples. • This study describes the pattern of electrophoretic mobility obtained by DGGE gels and allows to determine the type of bacteria associated in the development of neonatal sepsis.

Genotipificación del virus del papiloma humano en mujeres que asisten a un hospital gineco-obstétrico de tercer nivel de la Ciudad de México / Genotyping of human papillomavirus in women attending a third-level of gynecological-obstetric hospital in Mexico City

Objetivo: Determinar la frecuencia de infección por el virus del papiloma humano en pacientes que acudieron a un hospital de tercer nivel de atención en la Ciudad de México. Método: Se realizó un estudio prospectivo, transversal y descriptivo que incluyó 65 mujeres entre 15 a 46 años que asistieron a consulta para atención gineco-obstétrica. A todas las participantes se les tomó una muestra cervical para la detección/genotipificación del papiloma virus mediante la prueba Linear Array HPV Genotyping Test in vitro® (Roche Molecular Systems, Inc., Branchburg, NJ). Resultados: Un total de 36 (55,4%) pacientes resultaron positivas al virus, en las que se identificaron 65 genotipos virales tanto en infección única (38,9%) como en infección por múltiples (61,1%) genotipos. El 29,2% de los genotipos identificados, fueron de alto riesgo. Los genotipos de alto riesgo más frecuentes fueron: VPH52 y 51; mientras que los genotipos de bajo riesgo más comunes fueron: VPH6 y 53. Un tercio de las pacientes con infección mostraron al menos un genotipo de alto riesgo. Conclusión: En este estudio, se observó una frecuencia relativamente baja de genotipos de alto riesgo del virus del papiloma humano, sin embargo se identificó un porcentaje importante de co-infección por múltiples genotipos. Por esta razón, se considera necesario dar seguimiento a mediano y largo plazo para monitorear la evolución de la infección.

Objective: To identify which are the most frequent genotypes of human papilloma virus among a group of gynecologic-obstetric patients at tertiary care hospital in Mexico City. Method: A prospective and descriptive cross-sectional study was carried out among a group of 65 women, aged 15-46 years, receiving gynecological-obstetric care. Cervical specimens were taken from all participants for direct HPV detection/ genotyping by means of a Linear Array HPV Genotyping Test in vitro® (Roche Molecular Systems, Inc., Branchburg, NJ). Results: Virus detection was achieved in 36 patients (55.4%), with a total of 65 genotypes, either as single (38.9%) or multiple-genotype (61.1%) infections. High risk genotypes accounted for only 29.2% of all genotype. The most frequent high risk genotypes were HPV52 and 51, while HPV6 and 53 were the most frequent low risk ones. At least one high risk genotype was present in one third of infected patients. Conclusion: The relative low frequency of oncogenic human papilloma virus genotypes among the women in this study was observed, however a significant percentage of co-infection with multiple genotypes were identified. Thus, mid- to long-term follow up might be necessary for those patients to monitor the evolution of the infection.

In vitro secretion profiles of interleukin (IL)-1beta, IL-6, IL-8, IL-10, and TNF alpha after selective infection with Escherichia coli in human fetal membranes.

BACKGROUND: Chorioamniotic membranes infection is a pathologic condition in which an abnormal secretion of proinflammatory cytokines halts fetal immune tolerance. The aim of the present study was to evaluate the functional response of human chorioamniotic membranes, as well as the individual contribution of the amnion and choriodecidua after stimulation with Escherichia coli, a pathogen associated with preterm labor. METHODS: Explants of chorioamniotic membranes from 10 women (37-40 weeks of gestation) were mounted and cultured in a Transwell system, which allowed us to test the amnion and choriodecidua compartments independently. Escherichia coli (1 x 10 6 CFU/mL) was added to either the amniotic or the choriodecidual regions or both; after a 24-h incubation, the secretion of IL-1beta, IL-6, TNFalpha, IL-8, and IL-10 in both compartments was measured using a specific ELISA. Data were analyzed by Kruskal-Wallis one-way analysis of variance. RESULTS: After stimulation with Escherichia coli, the choriodecidua compartment showed an increase in the secretion of IL-1beta (21-fold), IL-6 (2-fold), IL-8 (6-fold), and IL-10 (37-fold), regardless of which side of the membrane was stimulated; TNFalpha secretion augmented (22-fold) also but only when the stimulus was applied simultaneously to both sides. When the amnion was stimulated directly, the level of IL-1beta (13-fold) rose significantly; however, the increase in IL-8 secretion was larger (20-fold), regardless of the primary site of infection. TNFalpha secretion in the amnion compartment rose markedly only when Escherichia coli was simultaneously applied to both sides. CONCLUSION: Selective stimulation of fetal membranes with Escherichia coli results in a differential production of IL-1beta, IL-6, TNFalpha, IL-8, and IL-10. These tissues were less responsive when the amnion side was stimulated. This is in agreement with the hypothesis that the choriodecidua may play a primary role during an ascending intrauterine infection, being the main barrier to progression of the infection into the amniotic cavity. Therefore, the tissue-specific capacities for the secretion of these immune modulators could be a determining factor for the degree of severity of the inflammation process in fetal membranes.

Evidence of in vitro differential secretion of 72 and 92 kDa type IV collagenases after selective exposure to lipopolysaccharide in human fetal membranes.

Premature rupture of chorioamniotic membranes complicated with intrauterine infection has been associated to degradation of extracellular matrix (ECM), which could explain local morphological changes. We used a culture system in which the chorioamniotic membranes form two independent chambers, allowing for the selective stimulation of either the amnion (AMN) and/or the choriodecidua (CHD) regions. Lipopolysaccharide (500 ng/ml) was added to the AMN and/or the CHD; secretions and gelatinolytic activity of matrix metalloproteinase (MMP)-2 and MMP-9 were measured in both compartments by enzyme-linked immunosorbent assay (ELISA) and zymography. Secretions of TIMP-1, TIMP-2 and TIMP-4 were measured by ELISA. Both metalloproteinases were immunolocalized in tissue sections. All stimulation modalities induced a similar proMMP-2 and proMMP-9 secretion pattern in the CHD with concentrations of 2.49 ng/ml and 90.91 pg/ml, respectively; the AMN showed no significant changes. The active forms of both enzymes did not change with any stimulation modality. TIMP-1, TIMP-2 and TIMP-4 secretions remained without significant changes (P = 0.41). ECM degradation and structural disarrangement were evident after stimulation. Secretion of proMMP-2 and proMMP-9 mainly in the CHD, presence of active forms associated to the tissue and minor changes in TIMPs secretion could favor ECM degradation and explain the weakening and thinning associated with the pathological rupture of chorioamniotic membranes.

Resistance of uropathogenic bacteria to first-line antibiotics in mexico city: A multicenter susceptibility analysis.

UNLABELLED: Abstract. BACKGROUND: Growing antibiotic resistance demands the constant reassessment of antimicrobial efficacy, particularly in countries with wide antibiotic abuse, where higher resistance prevalence is often found. Knowledge of resistance trends is particularly important when prescribing antibiotics empirically, as is usually the case for urinary tract infections (UTIs). Currently, in Mexico City, ampicillin, cotrimoxazole (trimethoprim/sulfamethoxazole), and ciprofloxacin are used as "first-line" antibiotic treatment for UTI. OBJECTIVE: The aim of this study was to analyze the resistance of bacterial isolates to antibiotics, with a focus on first-line antibiotics, in Mexican pediatric patients and sexually active or pregnant female outpatients. METHODS: In this multicenter susceptibility analysis, bacterial isolates from urine samples collected from pediatric patients and sexually-active or pregnant female outpatients presenting with acute, uncomplicated UTIs in Mexico City from January 2006 through June 2006, were included in the study. Samples were tested for susceptibility to 10 antibiotics by the disk-diffusion method. RESULTS: Four-hundred and seventeen bacterial isolates were derived from sexually active or pregnant female outpatients (324 Escherichia coli) and pediatric patients (93 Klebsiella pneumoniae). We found a high prevalence of resistance towards the drugs used as "first-line" when treating UTIs: ampicillin, cotrimoxazole, and ciprofloxacin (79%, 60%, and 24% resistance, respectively). Ninety-eight percent of K pneumoniae isolates were resistant to ampicillin, whereas 66% of the E coli isolates were resistant to cotrimoxazole. Resistance towards third-generation cephalosporins was also high (6%-8% of E coli and 10%-28% of K pneumoniae). This was possibly caused by chromosomal ß-lactamases, as 30% of all isolates were also resistant to amoxicillin/clavulanate. In contrast, 98% of the E coli isolates and 84% of the K pneumoniae strains (96% of all isolates) were found to be susceptible to nitrofurantoin, which has been in clinical use for much longer than most other drugs in this study. CONCLUSION: In these urine samples from laboratories in Mexico City, resistance of K pneumoniae and E coli isolates to first-line treatment (ampicillin, cotrimoxazole, or ciprofloxacin) of UTI was high, whereas most E coli and K pneumoniae isolates were susceptible to nitrofurantoin and the fourth-generation cephalosporin cefepime. (Curr Ther Res Clin Exp. 2007;68:120-126) Copyright © 2007 Excerpta Medica, Inc.

[High prevalence of group B Streptococcus colonization in Mexican pregnant women]. / Elevada prevalencia de colonización por Streptococcus del grupo B en mujeres mexicanas embarazadas.

OBJECTIVE: To determine the prevalence of group B Streptococcus (GBS) colonization in two anatomical sites in Mexican women of childbearing age, as well as the associated risk factors. PATIENTS AND METHOD: A retrospective cohort analysis was made with two groups of women between 14 and 44 years old. We formed two groups of 72 women; one had a recent positive group B Streptococcus culture and the other, paired by age and culture date, had a negative culture of the same bacterium. All of them answered a validated questionnaire and two rectal swabs were obtained and cultured for isolation of group B Streptococcus. RESULTS: Prevalence of GBS colonization was 18% for two anatomical sites (heavy colonization), and 37% for one anatomical site; the overall prevalence was 54.9%. Three or more sexual partners increased by 4-fold the risk of heavy GBS colonization (p < 0.01). In this study 49 (34%) women were pregnant, 26 (53%) of them were colonized by GBS and 7 (14.3%) were heavy colonized. CONCLUSIONS: Prevalence of GBS during pregnancy in Mexican women was higher than the reported previously, even in developed countries. Risk of colonization increased by 4-fold with a history of three or more sexual partners.

Interacción de cepas verocitotóxicas de Escherichia coli y rotavirus en un brote de diarrea en becerros / Interaction of Escherichia coli verocytotoxin strains and rotavirus in an outbreak of calves diarrhoea

Se estudió un brote de diarrea hemorrágica en becerros de 1 a 20 días de edad, de curso agudo, con edema gastrointestinal, signos nerviosos y sin respuesta al tratamiento con antibióticos. Se realizaron estudios parasitológicos, bacteriológicos e identificación de rotavirus. Se determinó en las cepas de Escherichia coli aisladas la capacidad de producir citotoxinas sobre células vero. El 63.7 por ciento de las cepas aisladas de E.coli resultaron verocitotóxicas (productoras de toxina vero o de toxina shiga, Stx), estas cepas se aislaron del 86.5 por ciento de los animales afectados. En 24 por ciento de estos animales se determinó la presencia de rotavirus mediante electroforesis en PAGE. Se encontraron variaciones en la movilidad electroforética de las bandas. Todos los casos con identificación de rotavirus correspondieron con la presencia de cepas de Escherichia coli productoras de toxina siga (STEC) en el intestino. El porcentaje de riesgo calculado, de presentar infección con rotavirus atribuible a la infección con E.coli STX, fue de 100, no existió, en cambio, riesgo de presentar cepas STX si se presentaba una infección primaria con rotavirus. Los datos sugieren que las cepas citotóxicas son agentes primarios de infección y toxemia neonatal en bovinos; a la vez, se refuerza el probable papel de los bovinos como reservorios de cepas citotóxicas que afectan al humano y determinan el síndrome urémico hemolítico.

Perfil clínico-microbiológico de la infección urinaria por Staphylococcus en pacientes ginecoobstétricas / Clinico-microbiological profile of urinary infection by Staphylococcus in gyneco-obstetrical patients

Las entrobacterias son los microorganismos que con mayor frecuencia se encuantran involucrados en la etiología de la infección urinaria (IVU).Los cocos Gram positivos también son causa de IVU, especialmente el Staphylococcus saprophyticus. Para conocer el compprtamiento clínico y microbiológico de las IVU por Staphyloccus en pacientes gineco-obstétricas, realizamos un estudio prospectivo de los casos identificados en el Instituto Nacional de Perinatología en el período de Enero a julio de 1992. Se diagnosticaron 32 casos, de los cuales 19 correspondieron a cistouretritis, 12 a bacteriuria asintomática y uno a pielonefritis. Veitinueve de los aislamientos correspondieron a Staphylococcus coagulasa negativos (SCN), de estos el staphylococcus epidermidis fue el más recuperado. El 82.7 por ciento de las cepas de SCN fueron productoras de slime. El patrón de sensibilidad antimicrobiana mostró un porcentaje bajo la resistencia para la mayoría de los antimicrobianos probados, con excepción de penicilina sódica y gentamicina.