Pericardial tamponade: a new perspective on echocardiographic features and application of a prediction score.

Few clinical decision rules have been used to guide clinical management and predict outcomes in patients with pericardial tamponade. The objectives of this study are to identify the echocardiographic features associated with adverse outcomes in patients with pericardial effusions requiring pericardiocentesis and to apply a previously described four-point clinical and echocardiographic score to predict clinical outcomes over 24-hr, 30-day, and 1-year intervals. We performed a retrospective cohort review of patients who had transthoracic echocardiogram (TTE) performed and underwent pericardiocentesis within 48 h of emergency department presentation at two large tertiary care institutions. We constructed different stepwise logistic regression models and examined the associations of TTE characteristics and clinical features with ICU admission, hospital length of stay (h-LOS), and survival. The data set was then employed against a previously proposed scoring system to predict factors associated with clinical outcomes over 24 hr, 30 days, and 1 year. Two hundred thirty-nine patients were included in the final analysis. Echocardiographic characteristics of patients with pericardial tamponade who underwent pericardiocentesis are as follows: 69.1% right ventricular (RV) diastolic collapse, 62.3% exaggerated mitral valve (MV) inflow velocities, 56.4% inferior vena cava (IVC) plethora, and 53.4% right atrial (RA) systolic collapse. Increase in systolic blood pressure and increased variation in MV inflow velocity were associated with reduced ICU admission [OR: 0.94 (CI 0.90, 0.99), 0.28 (CI 0.09, 0.89), respectively]. In addition, a history of malignancy increased the length of hospital stay by about 3.89 days (CI 1.43-6.35, p < 0.01) and prior pericardiocentesis history was associated with 4.82-day increase in hospital stay (CI 1.19-8.45, p = 0.01). In utilizing the previously published prediction score, we found no statistically significant correlation in predicting survival. RV diastolic collapse and exaggerated MV inflow velocity were the most common echocardiographic findings in patients requiring pericardiocentesis. Contrary to prior studies, exaggerated MV inflow velocity was associated with reduced ICU admission. In addition, a previously described prediction score did not correlate with decreased survival in this cohort.

Indoor air pollution from secondhand tobacco smoke, solid fuels, and kerosene in homes with active tuberculosis disease in South Africa.

OBJECTIVES: Secondhand tobacco smoke (SHS), use of solid fuels, and kerosene may play an important role in perpetuating the tuberculosis (TB) epidemic. The purpose of this study was to explore the prevalence of household air pollution (HAP) from these sources in homes of someone with TB in a high HIV-prevalence setting. A convenience sample of homes and household members participating in an ongoing active case-finding study in Matlosana district townships surrounding Klerksdorp, South Africa were included. RESULTS: We found a high prevalence of air pollution from SHS, solid fuels, and kerosene among individuals in homes with a case of prevalent active TB disease in Klerksdorp, South Africa. Adults in 40% of homes reported a daily smoker in the home, and 70% of homes had detectable air nicotine. In homes with a history of previous TB (prior to but not including the index case) as compared to those without previous TB, both SHS (83% vs. 65%, respectively) and solid/kerosene fuel use for more than 1 h/day (27% vs. 21%, respectively) were more prevalent. Larger studies are needed to estimate the risk of TB from these types of air pollution in HIV infected individuals and settings with high HIV prevalence.

Insights into species divergence and the evolution of hermaphroditism from fertile interspecies hybrids of Caenorhabditis nematodes.

The architecture of both phenotypic variation and reproductive isolation are important problems in evolutionary genetics. The nematode genus Caenorhabditis includes both gonochoristic (male/female) and androdioecious (male/hermaprodite) species. However, the natural genetic variants distinguishing reproductive mode remain unknown, and nothing is known about the genetic basis of postzygotic isolation in the genus. Here we describe the hybrid genetics of the first Caenorhabditis species pair capable of producing fertile hybrid progeny, the gonochoristic Caenorhabditis sp. 9 and the androdioecious C. briggsae. Though many interspecies F(1) arrest during embryogenesis, a viable subset develops into fertile females and sterile males. Reciprocal parental crosses reveal asymmetry in male-specific viability, female fertility, and backcross viability. Selfing and spermatogenesis are extremely rare in XX F(1), and almost all hybrid self-progeny are inviable. Consistent with this, F(1) females do not express male-specific molecular germline markers. We also investigated three approaches to producing hybrid hermaphrodites. A dominant mutagenesis screen for self-fertile F(1) hybrids was unsuccessful. Polyploid F(1) hybrids with increased C. briggsae genomic material did show elevated rates of selfing, but selfed progeny were mostly inviable. Finally, the use of backcrosses to render the hybrid genome partial homozygous for C. briggsae alleles did not increase the incidence of selfing or spermatogenesis relative to the F(1) generation. These hybrid animals were genotyped at 23 loci, and significant segregation distortion (biased against C. briggsae) was detected at 13 loci. This, combined with an absence of productive hybrid selfing, prevents formulation of simple hypotheses about the genetic architecture of hermaphroditism. In the near future, this hybrid system will likely be fruitful for understanding the genetics of reproductive isolation in Caenorhabditis.