Causal analysis of fetal death in high-risk pregnancies.

OBJECTIVES: To determine the causes of fetal death among the stillbirths using two classification systems from 22 weeks of gestation in a period of three years in high-risk pregnancies. This is a retrospective observational study. METHODS: The National Institute of Perinatal Health in Mexico City is a Level 3 care referral center attending high-risk pregnancies from throughout the country. The population consisted of patients with fetal death during a three-year period. Between January 2016 and December 2018, all stillbirths were examined in the Pathology Department by a pathologist and a medical geneticist. Stillbirth was defined as a fetal death occurring after 22 weeks of gestation. RESULTS: Main outcome measures: Causal analysis of fetal death using the International Statistical Classification of Disease and Related Health Problems-Perinatal Mortality (ICD-PM) and initial causes of fetal death (INCODE) classification systems. A total of 297 stillborn neonates were studied. The distribution of gestational age in antepartum stillbirths (55.2%) showed a bimodal curve, 36% occurred between 24 and 27 weeks and 32% between 32 and 36 weeks. In comparison, the majority (86%) of intrapartum deaths (44.8%) were less than 28 weeks of gestation. Of the 273 women enrolled, 93 (34%) consented to a complete fetal autopsy. The INCODE system showed a present cause in 42%, a possible cause in 54% and a probable cause in 93% of patients. CONCLUSIONS: The principal causes of antepartum death were fetal abnormalities and pathologic placental conditions and the principal causes of intrapartum death were complications of pregnancy which caused a premature labor and infections.

Endemic and Epidemic Human Alphavirus Infections in Eastern Panama: An Analysis of Population-Based Cross-Sectional Surveys.

Madariaga virus (MADV) has recently been associated with severe human disease in Panama, where the closely related Venezuelan equine encephalitis virus (VEEV) also circulates. In June 2017, a fatal MADV infection was confirmed in a community of Darien Province. We conducted a cross-sectional outbreak investigation with human and mosquito collections in July 2017, where sera were tested for alphavirus antibodies and viral RNA. In addition, by applying a catalytic, force-of-infection (FOI) statistical model to two serosurveys from Darien Province in 2012 and 2017, we investigated whether endemic or epidemic alphavirus transmission occurred historically. In 2017, MADV and VEEV IgM seroprevalences were 1.6% and 4.4%, respectively; IgG antibody prevalences were MADV: 13.2%, VEEV: 16.8%, Una virus (UNAV): 16.0%, and Mayaro virus: 1.1%. Active viral circulation was not detected. Evidence of MADV and UNAV infection was found near households, raising questions about its vectors and enzootic transmission cycles. Insomnia was associated with MADV and VEEV infections, depression symptoms were associated with MADV, and dizziness with VEEV and UNAV. Force-of-infection analyses suggest endemic alphavirus transmission historically, with recent increased human exposure to MADV and VEEV in Aruza and Mercadeo, respectively. The lack of additional neurological cases suggests that severe MADV and VEEV infections occur only rarely. Our results indicate that over the past five decades, alphavirus infections have occurred at low levels in eastern Panama, but that MADV and VEEV infections have recently increased-potentially during the past decade. Endemic infections and outbreaks of MADV and VEEV appear to differ spatially in some locations of eastern Panama.

Implementation of bamboo and monkey-pot traps for the sampling cavity-breeding mosquitoes in Darién, Panama.

Despite the importance of Aedes, Haemagogus and Sabethes in the transmission of yellow fever virus (YFV) and the public health impacts of recent YFV epidemics in the Americas, relatively little has been reported on the biology and ecology of these vectors. Many Aedes, Haemagogus and Sabethes spp. in the American tropics inhabit and develop in the forest canopy and are difficult to sample with conventional entomological surveillance methods. We tested the utility of two previously developed phytotelmata-style oviposition traps (bamboo Guadua angustifolia) and (monkey-pot Lecythis minor), for collecting immature forms of these mosquitoes in a forest near the community of Aruza Abajo, Darién Province, Panama. Our results showed distribution of mosquito species emerging from the two types of traps was found to be significantly different (X2 = 210.23; df = 14; P < 0.001), with significantly greater numbers of Sabethes (Peytonulus) aurescens (Lutz) and Sabethes (Peytonulus) undosus (Coquillett) emerging from the bamboo traps. More females of Sabethes (Sabethes) cyaneus (Fabricius) were captured in the monkey-pot traps, although the difference was not significant. No differences were observed in the average time to emergence for the two traps. These results suggest that various phytotelmata-style traps, including monkey-pot and bamboo, could be used to improve entomological surveillance of YFV vectors in the American tropic.

Autophagy, Inflammation, and Metabolism (AIM) Center in its second year.

The NIH-funded center for autophagy research named Autophagy, Inflammation, and Metabolism (AIM) Center of Biomedical Research Excellence, located at the University of New Mexico Health Science Center is now completing its second year as a working center with a mission to promote autophagy research locally, nationally, and internationally. The center has thus far supported a cadre of 6 junior faculty (mentored PIs; mPIs) at a near-R01 level of funding. Two mPIs have graduated by obtaining their independent R01 funding and 3 of the remaining 4 have won significant funding from NIH in the form of R21 and R56 awards. The first year and a half of setting up the center has been punctuated by completion of renovations and acquisition and upgrades for equipment supporting autophagy, inflammation and metabolism studies. The scientific cores usage, and the growth of new studies is promoted through pilot grants and several types of enablement initiatives. The intent to cultivate AIM as a scholarly hub for autophagy and related studies is manifested in its Vibrant Campus Initiative, and the Tuesday AIM Seminar series, as well as by hosting a major scientific event, the 2019 AIM symposium, with nearly one third of the faculty from the International Council of Affiliate Members being present and leading sessions, giving talks, and conducting workshop activities. These and other events are often videostreamed for a worldwide scientific audience, and information about events at AIM and elsewhere are disseminated on Twitter and can be followed on the AIM web site. AIM intends to invigorate research on overlapping areas between autophagy, inflammation and metabolism with a number of new initiatives to promote metabolomic research. With the turnover of mPIs as they obtain their independent funding, new junior faculty are recruited and appointed as mPIs. All these activities are in keeping with AIM's intention to enable the next generation of autophagy researchers and help anchor, disseminate, and convey the depth and excitement of the autophagy field.

Hepatitis B infection of the liver in chronic hepatitis C without detectable hepatitis B virus DNA in serum.

Hepatitis B virus (HBV) DNA may persist in the liver in the absence of serum HBV-DNA after a self-limited acute hepatitis B. This may also occur in patients with chronic hepatitis C virus (HCV) infection but its prevalence and its impact on liver histology is unknown. HBV-DNA was tested by polymerase chain reaction (PCR) and by in situ hybridisation in liver biopsies from 98 patients with chronic hepatitis C who were hepatitis B surface antigen negative and serum HBV-DNA negative by PCR. HBV-DNA resulted positive in the liver of 37/98 (37.7%) patients without serum HBV-DNA. To test whether these patients had serum HBV-DNA levels under the detection limit of the PCR assay used in this study (50 copies/ml), PCR products in which HBV-DNA was undetectable after visualization of agarose gels were analysed by dot-blot hybridisation. With this method, HBV-DNA was positive in serum of 12/37 patients with liver HBV-DNA. Thus, 25/98 (25.5%) patients have HBV-DNA detectable only in liver. This was confirmed by in situ hybridisation, the percentage of infected hepatocytes ranging from 0.1% to 12%. In patients in whom the HCV infection was shorter than 20 years, HBV infected patients had higher (P = 0.01) fibrosis score (1.64 +/- 1.21) than HBV negative cases (0.53 +/- 0.66). In conclusion, a significant proportion of patients with chronic HCV infection have HBV-DNA in the liver in the absence of viral DNA in serum. The impact of this finding on liver histology deserves further research.

Distribution of hepatitis B virus in the liver of chronic hepatitis C patients with occult hepatitis B virus infection.

Although occult hepatitis B virus (HBV) infection (HBV-DNA in serum in the absence of hepatitis B surface antigen [HBsAg]) is common in chronic hepatitis C, its characteristics are not well known. In this work, the presence of HBV-DNA (by polymerase chain reaction; PCR) and its distribution (by in situ hybridization) in liver biopsies and peripheral blood mononuclear cells (PBMCs) from 32 patients with chronic hepatitis C and occult HBV infection and in 20 HBsAg chronic carriers were determined. The results showed that serum HBV-DNA levels were statistically lower (P = 0.001) in patients with occult HBV infection than in HBsAg chronic carriers. The HBV infection pattern in liver cells was identical between patients with occult HBV infection and those with chronic hepatitis B. However, the mean percentage of HBV-infected hepatocytes was significantly lower (P = 0.001) in patients with occult HBV infection (5 +/- 4.44%) than in HBsAg chronic carriers (17.99 +/- 11.58%). All patients with chronic hepatitis B have HBV-DNA in their PBMCs while this occurred in 50% of the cases with occult HBV infection. In conclusion, patients with occult HBV infection have a low number of HBV-infected hepatocytes and this fact could explain the lack of HBsAg detection and low viremia levels found in these cases.

TT virus replicates in stimulated but not in nonstimulated peripheral blood mononuclear cells.

TT virus (TTV) is an unenveloped, single-stranded, circular-DNA virus which resembles members of the Circoviridae, that is commonly found in humans and which lacks pathological consequences for the infected host. TTV replication has been demonstrated in bone marrow cells but not in peripheral blood mononuclear cells (PBMC), suggesting that hematopoietic cells must be activated to support TTV replication. To test this hypothesis, PBMC from two naturally TTV-infected individuals and from two healthy TTV-DNA negative donors infected in vitro with a TTV-DNA-positive serum were cultured in the presence (stimulated) or absence (unstimulated) of phytohemagglutinin, lipopolysaccharide, and interleukin-2. TTV-DNA was detected in both stimulated and unstimulated PBMC. However, TTV-DNA replicative intermediates and mRNA were detected only in stimulated PBMC. Furthermore, TTV-DNA and mRNA were detected in PBMC from two TTV negative donors reinfected with supernatants from TTV-infected stimulated cells but not when using culture supernatants from unstimulated cells. These results demonstrate that TTV replicates in PBMC only when stimulated.