10 research outputs found

    Hypoxia Is Not a Main Stress When Mycobacterium tuberculosis Is in a Dormancy-Like Long-Chain Fatty Acid Environment

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    The capacity of Mycobacterium tuberculosis (Mtb) to sense, respond and adapt to a variable and hostile environment within the host makes it one of the most successful human pathogens. During different stages of infection, Mtb is surrounded by a plethora of lipid molecules and current evidence points out the relevance of fatty acids during the infectious process. In this study, we have compared the transcriptional response of Mtb to hypoxia in cultures supplemented with a mix of even long-chain fatty acids or dextrose as main carbon sources. Using RNA sequencing, we have identified differential expressed genes in early and late hypoxia, defined according to the in vitro Wayne and Hayes model, and compared the results with the exponential phase of growth in both carbon sources. We show that the number of genes over-expressed in the lipid medium was quite low in both, early and late hypoxia, relative to conditions including dextrose, with the exception of transcripts of stable and non-coding RNAs, which were more expressed in the fatty acid medium. We found that sigB and sigE were over-expressed in the early phase of hypoxia, confirming their pivotal role in early adaptation to low oxygen concentration independently of the carbon source. A drastic contrast was found with the transcriptional regulatory factors at early hypoxia. Only 2 transcriptional factors were over-expressed in early hypoxia in the lipid medium compared to 37 that were over-expressed in the dextrose medium. Instead of Rv0081, known to be the central regulator of hypoxia in dextrose, Rv2745c (ClgR), seems to play a main role in hypoxia in the fatty acid medium. The low level of genes associated to the stress-response during their adaptation to hypoxia in fatty acids, suggests that this lipid environment makes hypoxia a less stressful condition for the tubercle bacilli. Taken all together, these results indicate that the presence of lipid molecules shapes the metabolic response of Mtb to an adaptive state for different stresses within the host, including hypoxia. This fact could explain the success of Mtb to establish long-term survival during latent infection

    The Immune Response in Adipocytes and Their Susceptibility to Infection: A Possible Relationship with Infectobesity

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    The current obesity pandemic has been expanding in both developing and developed countries. This suggests that the factors contributing to this condition need to be reconsidered since some new factors are arising as etiological causes of this disease. Moreover, recent clinical and experimental findings have shown an association between the progress of obesity and some infections, and the functions of adipose tissues, which involve cell metabolism and adipokine release, among others. Furthermore, it has recently been reported that adipocytes could either be reservoirs for these pathogens or play an active role in this process. In addition, there is abundant evidence indicating that during obesity, the immune system is exacerbated, suggesting an increased susceptibility of the patient to the development of several forms of illness or death. Thus, there could be a relationship between infection as a trigger for an increase in adipose cells and the impact on the metabolism that contributes to the development of obesity. In this review, we describe the findings concerning the role of adipose tissue as a mediator in the immune response as well as the possible role of adipocytes as infection targets, with both roles constituting a possible cause of obesity

    Association between 25-OH Vitamin D Deficiency and COVID-19 Severity in Pregnant Women

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    Evidence from studies in the general population suggests an association between vitamin D insufficiency/deficiency and COVID-19 susceptibility and disease severity. The present study was performed on 165 third-trimester pregnant women at the time of delivery. Seventy-nine women tested negative for SARS-CoV-2. From 86 women testing positive, 32 were asymptomatic, 44 presented a mild form of the disease, and 10 experienced severe symptoms. Serum 25-OH vitamin D levels were measured on blood samples collected on admission. Low vitamin D levels were detected in symptomatic but not asymptomatic COVID-19 patients compared to healthy women (p = 0.0227). In addition, 20 (45.4%) pregnant women in the mild COVID-19 group and 6 (60%) in the severe group were vitamin D deficient (p = 0.030). On the other hand, lasso regression analysis showed that 25-OH vitamin D deficiency is an independent predictor of severe COVID-19 with an odds ratio (OR) of 5.81 (95% CI: 1.108–30.541; p = 0.037). These results show the relationship between vitamin D deficiency in pregnant women and the severity of COVID-19 infection and support the recommendation to supplement with vitamin D to avoid worse COVID-19 outcomes during pregnancy

    Collateral Damage in the Placenta during Viral Infection in Pregnancy: A Possible Mechanism for Vertical Transmission and an Adverse Pregnancy Outcome

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    In mammals, the placenta is a connection between a mother and a new developing organism. This tissue has a protective function against some microorganisms, transports nutrients, and exchanges gases and excretory substances between the mother and the fetus. Placental tissue is mainly composed of chorionic villi functional units called trophoblasts (cytotrophoblasts, the syncytiotrophoblast, and extravillous trophoblasts). However, some viruses have developed mechanisms that help them invade the placenta, causing various conditions such as necrosis, poor perfusion, and membrane rupture which, in turn, can impact the development of the fetus and put the mother’s health at risk. In this study, we collected the most relevant information about viral infection during pregnancy which can affect both the mother and the fetus, leading to an increase in the probability of vertical transmission. Knowing these mechanisms could be relevant for new research in the maternal–fetal context and may provide options for new therapeutic targets and biomarkers in fetal prognosis

    Phenotypic and Genotypic Drug Resistance of <i>Mycobacterium tuberculosis</i> Strains Isolated from HIV-Infected Patients from a Third-Level Public Hospital in Mexico

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    Background: Drug-resistant tuberculosis (TB) is associated with higher mortality rates in patients with human immunodeficiency virus (HIV). In Mexico, the number of deaths due to TB among the HIV-positive population has tripled in recent years. Methods: Ninety-three Mycobacterium tuberculosis strains isolated from the same number of HIV-infected patients treated in a public hospital in Mexico City were studied to determine the drug resistance to first- and second-line anti-TB drugs and to identify the mutations associated with the resistance. Results: Of the 93 patients, 82.7% were new TB cases, 86% were male, and 73% had extrapulmonary TB. Most patients (94%) with a CD4 T-lymphocyte count 3 were associated with extrapulmonary TB (p 350 cells/mm3 were associated with pulmonary TB (p = 0.0011). Eighty-two strains were pan-susceptible, four mono-resistant, four poly-resistant, two multidrug-resistant, and one was extensively drug-resistant. In the rifampicin-resistant strains, rpoB S531L was the mutation most frequently identified, whereas the inhA C15T and katG S315T1 mutations were present in isoniazid-resistant strains. The extensively drug-resistant strain also contained the mutation gyrA D94A. Conclusions: These data highlight the need to promptly diagnose the drug resistance of M. tuberculosis among all HIV-infected patients by systematically offering access to first- and second-line drug susceptibility testing and to tailor the treatment regimen based on the resistance patterns to reduce the number of deaths in HIV-infected patients

    Prevalence of Depression, Anxiety, and Perceived Stress in Postpartum Mexican Women during the COVID-19 Lockdown

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    The COVID-19 lockdown represents a new challenge for mental health researchers and clinical practitioners. This cross-sectional study aimed to investigate the prevalence of depression, anxiety, and perceived stress in postpartum Mexican women. The study included 293, 4–12-week postpartum women over the age of 18. The Edinburgh Postpartum Depression Scale (EPDS), Trait-State Trait Anxiety Inventory (T-STAI), and Ten Perceived Stress Scale (PSS-10), which are all questionnaires validated for the Mexican population, were applied using a web-based online survey. Prevalence and 95% confidence intervals (CIs) were calculated. The mean ± standard deviation (SD) of the maternal age was 29.9 ± 6.3 years; the EPDS score: 11 ± 6, T-STAI score: 41.7 ± 12.3, and PSS-10 score: 17.1 ± 7. The prevalence (95% CI) of the postpartum depression symptoms was 39.2% (34–45%), trait anxiety symptoms were found among 46.1% (32–43%) of the participants, and moderate and high perceived stress were in 58% (52–64) and 10.9% (7.8–15) of the participants, respectively. The prevalence of depressive symptoms, generalized anxiety, and perceived stress was higher among postpartum Mexican women during the COVID-19 outbreak than before the lockdown. Our findings highlight the importance of monitoring perinatal mental health during pandemics and the need to design effective psychologic interventions for these patients

    Impact of Pre-Gestational BMI and Gestational Weight Gain on Fetal Development Outcomes in Adolescent Pregnant Women

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    Background. Gestational weight gain (GWG) constitutes an essential aspect of the gestational process. Due to factors such as pregestational body mass index (BMI), nutritional intake, level of physical activity, and psychological aspects, the recommended GWG may not be achieved, leading to adverse neonatal outcomes. Adolescents, due to their physiological and mental developmental stage, are at a higher risk of inappropriate GWG. Our aim is to highlight the importance of GWG in our population and to determine the correlation with perinatal outcomes. Methods. Pregnant adolescents who attended a tertiary care institution for prenatal care were included; maternal data such as preBMI and GWG were used to determine maternal and neonatal outcomes using the chi-square test and OR determination. Results. A total of 202 adolescent pregnant patients were included, comprising those with inadequate GWG (n = 70), adequate GWG (n = 85), and excessive GWG (n = 47). A statistically significant association was found between low BMI and inadequate GWG. Patients with inadequate GWG demonstrated a correlation with IUGR and low birth weight, while patients with excessive GWG gave birth to macrosomic neonates. Conclusion. We concluded that previous habits play a significant role in determining weight gain throughout pregnancy. GWG has a direct impact on neonatal growth and development

    Compartmentalized Innate Immune Response of Human Fetal Membranes against <i>Escherichia coli</i> Choriodecidual Infection

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    An infectious process into the uterine cavity represents a major endangered condition that compromises the immune privilege of the maternal–fetal unit and increases the risk for preterm birth (PTB) and premature rupture of membranes (PROM). Fetal membranes are active secretors of antimicrobial peptides (AMP), which limit bacterial growth, such as Escherichia coli. Nevertheless, the antibacterial responses displayed by chorioamniotic membranes against a choriodecidual E. coli infection have been briefly studied. The objective of this research was to characterize the profile of synthesis, activity, and spatial distribution of a broad panel of AMPs produced by fetal membranes in response to E. coli choriodecidual infection. Term human chorioamniotic membranes were mounted in a two independent compartment model in which the choriodecidual region was infected with live E. coli (1 × 105 CFU/mL). Amnion and choriodecidual AMP tissue levels and TNF-α and IL-1β secretion were measured by the enzyme-linked immunosorbent assay. The passage of bacterium through fetal membranes and their effect on structural continuity was followed for 24 h. Our results showed that E. coli infection caused a progressive mechanical disruption of the chorioamniotic membranes and an activated inflammatory environment. After the challenge, the amnion quickly (2–4 h) induced production of human beta defensins (HBD)-1, HBD-2, and LL-37. Afterwards (8–24 h), the amnion significantly produced HBD-1, HBD-2, HNP-1-3, S100A7, sPLA2, and elafin, whereas the choriodecidua induced LL-37 synthesis. Therefore, we noticed a temporal- and tissue-specific pattern regulation of the synthesis of AMPs by infected fetal membranes. However, fetal membranes were not able to contain the collagen degradation or the bacterial growth and migration despite the battery of produced AMPs, which deeply increases the risk for PTB and PROM. The mixture of recombinant HBDs at low concentrations resulted in increased bactericidal activity compared to each HBD alone in vitro, encouraging further research to study AMP combinations that may offer synergy to control drug-resistant infections in the perinatal period

    COVID-19 Infection in Pregnancy: PCR Cycle Thresholds, Placental Pathology, and Perinatal Outcomes

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    (1) This study aimed to evaluate characteristics, perinatal outcomes, and placental pathology of pregnant women with or without SARS-CoV-2 infection in the context of maternal PCR cycle threshold (CT) values. (2) This was a retrospective case-control study in a third-level health center in Mexico City with universal screening by RT-qPCR. The association of COVID-19 manifestations, preeclampsia, and preterm birth with maternal variables and CT values were assessed by logistic regression models and decision trees. (3) Accordingly, 828 and 298 women had a negative and positive test, respectively. Of those positive, only 2.6% of them presented mild to moderate symptoms. Clinical characteristics between both groups of women were similar. No associations between CT values were found for maternal features, such as pre-gestational BMI, age, and symptomatology. A significantly higher percentage of placental fibrinoid was seen with women with low CTs (&lt;25; p &lt; 0.01). Regarding perinatal outcomes, preeclampsia was found to be significantly associated with symptomatology but not with risk factors or CT values (p &lt; 0.01, aOR = 14.72). Moreover, 88.9% of women diagnosed with COVID-19 at &lt;35 gestational weeks and symptomatic developed preeclampsia. (4) The data support strong guidance for pregnancies with SARS-CoV-2 infection, in particular preeclampsia and placental pathology, which need further investigation
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