Elucidating virus-host interactions responsible for HIV-1 transmission is important for advancing HIV-1 prevention strategies. To this end, single genome amplification (SGA) and sequencing of HIV-1 within the context of a model of random virus evolution has made possible for the first time an unambiguous identification of transmitted/founder viruses and a precise estimation of their numbers. Here, we applied this approach to HIV-1 env analyses in a cohort of acutely infected men who have sex with men (MSM) and found that a high proportion (10 of 28; 36%) had been productively infected by more than one virus. In subjects with multivariant transmission, the minimum number of transmitted viruses ranged from 2 to 10 with viral recombination leading to rapid and extensive genetic shuffling among virus lineages. A combined analysis of these results, together with recently published findings based on identical SGA methods in largely heterosexual (HSX) cohorts, revealed a significantly higher frequency of multivariant transmission in MSM than in HSX [19 of 50 subjects (38%) versus 34 of 175 subjects (19%); Fisher's exact p = 0.008]. To further evaluate the SGA strategy for identifying transmitted/founder viruses, we analyzed 239 overlapping 5′ and 3′ half genome or env-only sequences from plasma viral RNA (vRNA) and blood mononuclear cell DNA in an MSM subject who had a particularly well-documented virus exposure history 3–6 days before symptom onset and 14–17 days before peak plasma viremia (47,600,000 vRNA molecules/ml). All 239 sequences coalesced to a single transmitted/founder virus genome in a time frame consistent with the clinical history, and a molecular clone of this genome encoded replication competent virus in accord with model predictions. Higher multiplicity of HIV-1 infection in MSM compared with HSX is consistent with the demonstrably higher epidemiological risk of virus acquisition in MSM and could indicate a greater challenge for HIV-1 vaccines than previously recognized.

These findings further articulate that breast cancer subtypes differ not only in tumor characteristics but also in their metastatic behavior, thus raising the possibility that this knowledge could potentially be used in determining the appropriate strategy for follow-up of patients with newly diagnosed breast cancer.

Recent studies indicate that sexual transmission of human immunodeficiency virus type 1 (HIV-1) generally results from productive infection by only one virus, a finding attributable to the mucosal barrier. Surprisingly, a recent study of injection drug users (IDUs) from St. Petersburg, Russia, also found most subjects to be acutely infected by a single virus. Here, we show by single-genome amplification and sequencing in a different IDU cohort that 60% of IDU subjects were infected by more than one virus, including one subject who was acutely infected by at least 16 viruses. Multivariant transmission was more common in IDUs than in heterosexuals (60% versus 19%; odds ratio, 6.14; 95% confidence interval [CI], 1.37 to 31.27; P ‫؍‬ 0.008). These findings highlight the diversity in HIV-1 infection risks among different IDU cohorts and the challenges faced by vaccines in protecting against this mode of infection.Elucidation of virus-host interactions during and immediately following the transmission event is one of the great challenges and opportunities in human immunodeficiency virus (HIV)/AIDS prevention research (14-16, 31, 34, 45). Recent innovations involving single-genome amplification (SGA), direct amplicon sequencing, and phylogenetic inference based on a model of random virus evolution (18)(19)(20)43) have allowed for the identification of transmitted/founder viruses that actually cross from donor to recipient, leading to productive HIV type 1 (HIV-1) infection. Our laboratory and others have made the surprising finding that HIV-1 transmission results from productive infection by a single transmitted/founder virus (or virally infected cell) in ϳ80% of HIV-infected heterosexuals and in ϳ60% of HIV-infected men who have sex with men (MSM) (1,13,18,24). These studies thus provided a precise quantitative estimate for the long-recognized genetic bottleneck in HIV-1 transmission (6, 11-13, 17, 25, 28, 30, 35, 38, 42, 47-49) and a plausible explanation for the low acquisition rate per coital act and for graded infection risks associated with different exposure routes and behaviors (15,36).In contrast to sexual transmission of HIV-1, virus transmission resulting from injection drug use has received relatively little attention (2, 3, 29, 42) despite the fact that injection drug use-associated transmission accounts for as many as 10% of new infections globally (26, 46). We hypothesized that SGA strategies developed for identifying transmitted/founder viruses following mucosal acquisition are applicable to deciphering transmission events following intravenous inoculation and that, due to the absence of a mucosal barrier, injection drug users (IDUs) exhibit a higher frequency of multiple-variant transmission and a wider range in numbers of transmitted viruses than do acutely infected heterosexual subjects. We obtained evidence in support of these hypotheses from the simian immunodeficiency virus (SIV)-Indian rhesus macaque infection model, where we showed that discrete low-diversity viral lineages emanating from singl...

Objectives We sought to evaluate predictors of stroke on LVAD from data available prior to implantation, and quantify stroke-related morbidity and mortality Background Stroke is a major complication after LVAD. Pre-implant factors that influence stroke are not well understood. Methods We evaluated all patients in the INTERMACS registry who were implanted with continuous-flow LVADs from May 1, 2012 to March 31, 2015. Preoperative risk factors for stroke, and stroke incidence, morbidity, and mortality were analyzed. Results During the study period, 7112 patients underwent CF LVAD placement. Median follow-up was 9.79 months (range 0.02–34.96 months). Of all patients, 752 (10.57%) had at least one stroke, with an incidence rate of 0.123 strokes per patient-year. 447 (51.38%) strokes were ischemic and 423 (48.62%) were hemorrhagic. Patients with hemorrhagic stroke had worse survival than those with ischemic strokes (30-day survival 45.3% vs. 80.7, p <0.001). Of patients with a first stroke, 13% had a second stroke. Pre-implant predictors of stroke were female gender (HR 1.51, 95% CI 1.25–1.82, p <0.001), pre-implant systolic blood pressure (HR 1.01, 95% CI 1.00–1.01, p = 0.002), heparin-induced thrombocytopenia (HIT) (HR 3.68, 95% CI 1.60–8.47, p = 0.002), intra-aortic balloon pump (IABP) (HR 1.21, 95% CI 1.01–1.46, p = 0.043), and primary cardiac diagnosis (ischemic/other/unknown) (p = 0.040). Conclusion Despite improvements in LVAD technology, stroke-related morbidity and mortality is substantial. Further investigation is necessary to decrease the risk of this devastating complication.

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To determine whether early coagulopathy affects the mortality associated with severe civilian pediatric trauma, trauma patients < 18 years of age admitted to a pediatric intensive care unit from 2001 to 2010 were evaluated. Patients with burns, primary asphyxiation, preexisting bleeding diathesis, lack of coagulation studies or transferred from other hospitals > 24 hours after injury were excluded. Age, gender, race, mechanism of injury, initial systolic blood pressure (SBP), Glasgow Coma Scale (GCS) score, Injury Severity Score (ISS), prothrombin time (PT), partial thromboplastin time (PTT), platelet count and International Normalized Ratio (INR) were recorded. An arterial or venous blood gas was performed, if clinically indicated. Coagulopathy was defined as an INR > 1.2. The primary outcome was in-hospital mortality. Secondary outcomes were lengths of ICU and hospital stay. Eight hundred three patients were included in the study. Overall mortality was 13.4%. The incidence of age-adjusted hypotension was 5.4%. Early coagulopathy was observed in 37.9% of patients. High ISS and/or hypotension were associated with early coagulopathy and higher mortality. Early coagulopathy was associated with a modest increase in mortality in pediatric trauma patients without traumatic brain injury (TBI). In contrast, the combination of TBI and early coagulopathy was associated with a four-fold increase in mortality in this patient population. Early coagulopathy is an independent predictor of mortality in civilian pediatric patients with severe trauma. The increase in mortality was particularly significant in patients with TBI either isolated or combined with other injuries, suggesting that a rapid correction of this coagulopathy could substantially decrease the mortality after TBI in pediatric trauma patients.

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Background-Inotrope use in heart failure treatment was associated with improved symptoms, but worse survival in clinical trials. However, these studies predated use of modern heart failure therapies. This study evaluates contemporary outcomes on long-term inotropes. Methods and Results-We collected baseline and postinotrope data on 197 patients discharged on inotropes between January 2007 and March 2013. Baseline characteristics, hemodynamic and clinical changes on inotropes, and survival were evaluated. Patients initiated on inotropes had refractory heart failure, with median baseline New York Heart Association class IV, cardiac index of 1.7 L/min per m 2 , pulmonary capillary wedge pressure of 25.6 mm Hg, and left ventricular ejection fraction of 18.7%. Inotropes were used in patients listed for transplant or scheduled for left ventricular assist device (LVAD; 60 patients), in patients being evaluated for LVAD/transplant (20 patients), for stabilization pending cardiac resynchronization therapy/percutaneous coronary intervention (4 patients), in patients who were offered LVAD but chose inotropes (15 patients), and for palliation (98 patients). Milrinone was used in 84.8% and dobutamine in 15.2%. At the end of the study, 68 patients had died, 24 were weaned off inotropes, 23 were transplanted, 32 received LVADs, and 50 remained on inotropes. Patients who received inotropes for palliation or those who preferred inotropes over LVAD had median survival of 9.0 months (interquartile range, 3.1-37.1 months), actuarial 1-year survival of 47.6%, and 2-year survival of 38.4%. Of 60 patients who were placed on inotropes as a bridge to transplant/LVAD, 55 were successfully maintained on inotropes until transplant/LVAD. Conclusions-Survival on inotropes for patients who are not candidates for transplant/LVAD is modestly better than previously reported, but remains poor. Inotropes are effective as a bridge to transplant/LVAD. (Circ Heart Fail.