Search

A history of cancer, opportunistic infections, shock, low hemoglobin levels, and resistance to therapy were risk factors for death in a study of 80 HIV patients with bacterial infections in the bloodstream. Intravenous catheters were the cause of the infection in 45% and 30% died from the infection.

A seventh blind test of crystal structure prediction has been organized by the Cambridge Crystallographic Data Centre. The results are presented in two parts, with this second part focusing on methods for ranking crystal structures in order of stability. The exercise involved standardized sets of structures seeded from a range of structure generation methods. Participants from 22 groups applied several periodic DFT-D methods, machine learned potentials, force fields derived from empirical data or quantum chemical calculations, and various combinations of the above. In addition, one non-energy-based scoring function was used. Results showed that periodic DFT-D methods overall agreed with experimental data within expected error margins, while one machine learned model, applying system-specific AIMnet potentials, agreed with experiment in many cases demonstrating promise as an efficient alternative to DFT-based methods. For target XXXII, a consensus was reached across periodic DFT methods, with consistently high predicted energies of experimental forms relative to the global minimum (above 4 kJ mol -1 at both low and ambient temperatures) suggesting a more stable polymorph is likely not yet observed. The calculation of free energies at ambient temperatures offered improvement of predictions only in some cases (for targets XXVII and XXXI). Several avenues for future research have been suggested, highlighting the need for greater efficiency considering the vast amounts of resources utilized in many cases., (open access.)

A seventh blind test of crystal structure prediction was organized by the Cambridge Crystallographic Data Centre featuring seven target systems of varying complexity: a silicon and iodine-containing molecule, a copper coordination complex, a near-rigid molecule, a cocrystal, a polymorphic small agrochemical, a highly flexible polymorphic drug candidate, and a polymorphic morpholine salt. In this first of two parts focusing on structure generation methods, many crystal structure prediction (CSP) methods performed well for the small but flexible agrochemical compound, successfully reproducing the experimentally observed crystal structures, while few groups were successful for the systems of higher complexity. A powder X-ray diffraction (PXRD) assisted exercise demonstrated the use of CSP in successfully determining a crystal structure from a low-quality PXRD pattern. The use of CSP in the prediction of likely cocrystal stoichiometry was also explored, demonstrating multiple possible approaches. Crystallographic disorder emerged as an important theme throughout the test as both a challenge for analysis and a major achievement where two groups blindly predicted the existence of disorder for the first time. Additionally, large-scale comparisons of the sets of predicted crystal structures also showed that some methods yield sets that largely contain the same crystal structures., (open access.)

Background: His-bundle pacing (HBP) has emerged as a promising technique to avoid pacing complications associated with dyssynchrony from right ventricular pacing, but data are limited to experienced operators and centres. We aimed to evaluate the implementation and outcomes of an HBP program in an Australian setting., Methods: Data were retrospectively collected on 140 consecutive HBP procedures attempted at three centres from March 2018 to September 2019. The cohort was divided into three groups (early: procedures 1-47, middle: 48-94, late: 95-140) to determine changes in procedural success in relation to operator experience., Results: Median age was 76 years (IQR 68-80 yrs); 69% were male. Atrial fibrillation was present in 59%, left ventricular ejection fraction (LVEF) ≤40% in 25%, and left and right bundle branch blocks present in 23% and 16% respectively, and atrioventricular (AV) block was present in 26%. Overall procedural success was 87%, median implant threshold 0.8V@1 ms, and QRS duration improved in 64% of procedures. Procedural success (early 83%, middle 89%, late 89%, p=0.58) was not different, while median procedural time (early 98 mins, middle 83 mins, late 70 mins, p<0.001) improved across operator experience groups. Lower success rates were identified for patients with AV block (73% vs. 92%, p<0.01), a previous device (69% vs. 89%, p=0.02), moderate-severe TR (69% vs. 88%, p=0.04), and when right-sided access was required (25% vs. 89%, p<0.01)., Conclusions: His-bundle pacing is a feasible procedure with continued improvement in procedural measures of success after an early learning period. The presence of AV block, a previous device, significant tricuspid regurgitation, or right-sided access may affect procedural success., (Copyright © 2020 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

The rich landscape of enantiotropically related polymorphic forms and their solid-state phase transitions of dl-2-aminoheptanoic acid (dl-AHE) has been explored using a range of complementary characterization techniques, and is largely exemplary of the polymorphic behavior of linear aliphatic amino acids. As many as five new polymorphic forms were found, connected by four fully reversible solid-state phase transitions. Two low temperature forms were refined in a high Z ' crystal structure, which is a new phenomenon for linear aliphatic amino acids. All five structures consist of two-dimensional hydrogen-bonded bilayers interconnected by weak van der Waals interactions. The single-crystal-to-single-crystal phase transitions involve shifts of bilayers and/or conformational changes in the aliphatic chain. Compared to two similar phase transitions of the related amino acid dl-norleucine, the enthalpies of transition and NMR chemical shift differences are notably smaller in dl-aminoheptanoic acid. This is explained to be a result of both the nature of the conformational changes and the increased chain length, weakening the interactions between the bilayers., Competing Interests: The authors declare no competing financial interest.

Little research has examined differences in HIV stigma versus MSM stigma and the role of these stigmas in depression for HIV-positive Latino and African American men who have sex with men (MSM), subgroups disproportionately impacted by HIV in the US. MSM stigma, HIV stigma, depression, stress and social support were examined among HIV-positive Latino (n = 100) and African American (n = 99) MSM patients at five HIV clinics in Los Angeles County, California. In multiple regression models, Latino MSM had higher HIV stigma scores (p = 0.002) but lower MSM stigma scores (p < 0.001) compared to African American MSM. General support and stress were associated with HIV stigma (p < 0.001), but not MSM stigma. Both HIV stigma (p < 0.0001) and MSM stigma (p < 0.0001) were associated with depression. These data underscore the differences in experienced stigma for Latino and African American MSM and can be used to shape effective stigma reduction programs and behavioral counseling.

Abstract HIV-infected patients frequently experience depression, drug use, and unstable housing but are often unable to access supportive services to manage these challenges. Data on barriers to needed supportive services are critical to improving patient access. Data from the Medical Monitoring Project (MMP), a national supplemental surveillance system for HIV-infected persons in care, was used to examine barriers to support service use and factors associated with need and unmet need for services. Interview data for 333 patients in care in 2007 and 2008 in Los Angeles County (LAC) showed that 71% (n=236) reported needing at least one supportive service and of these, 35% (n=83) reported at least one unmet need for services (46% Latino; 25% white; 83% male; 92% 30+; 77% gay/bisexual; 40% response rate). The main reasons that supportive services were not accessed included lack of information (47%; do not know where to go or who to call); an agency barrier (33%; system too confusing, wait list too long); or a financial/practical barrier (18%; too expensive, transportation problems). In a logistic regression that included all participants (n=333), African Americans (OR=3.1, 95% CI: 1.1-8.7) and those with incomes less than $10,000 were more likely to have service needs (odds ratio [OR]=3.5; 95% confidence interval [CI]: 1.3-9.3). Among those with at least one service need (n=236), those who were gay or bisexual were more likely to report at least one unmet service need (OR=2.8; 95% CI: 1.3-6.1). Disparities were found for need and unmet need for supportive services by race/ethnicity; income and sexual orientation. The reported reasons that services were not obtained suggest needed improvements in information dissemination on availability and location of HIV support services and more streamlined delivery of services.

Limited research has examined the role that social support, stress, stigma and HIV disclosure play in retention in HIV care for African Americans and Latinos. Among 398 Latino and African American men who have sex with men (MSM) and women, the major predictor of retention in HIV care was disclosure of HIV status to more social network members (OR = 1.5; 95% CI: 1.1, 1.9). Among those who had disclosed (n = 334), female gender (OR = 1.8, 95% CI: 1.1, 3.1) and disclosure of HIV status to more network members (OR = 1.5, 95% CI: 1.1, 1.9) was associated with retention in HIV care. General stress was associated with retention in care (OR = 1.2; 95% CI: 1.1, 1.3) for African American MSM who had disclosed. More MSM-stigma was associated with poorer retention (OR = 0.9; 95% CI: 0.8, 0.9) for Latino MSM. Interventions that help patients safely disclose their HIV status to more social network members may improve HIV care retention as would social network counseling for Latino MSM to reduce MSM-stigma.

Social support and stress have been poorly characterized for persons with HIV, particularly for racial/ethnic minorities. To address this gap, data on general and HIV-specific support and stress and social network characteristics were collected for 399 African American and Latino women and men who have sex with men (MSM) in Los Angeles County. African American (mean = 41; SD = 17) and Latina (mean = 40; SD = 19) women reported the highest general support. Stress was also highest for Latina women (mean = 18; SD = 11) and higher compared to Latino and African American MSM. African American and Latina women reported receiving most of their social support and stress from family members, while African American and Latino MSM received their support and stress from friends and providers. Finally, Latina and African American women disclosed their HIV status to more network members and received more HIV-specific support compared to MSM. Interventions are needed to help Latino and African American MSM enhance their support networks to manage a stigmatized illness.

The authors evaluated the impact of short-term intensive instruction by mental health professionals on police officers' attitudes toward the mentally ill and on their ability to distinguish between mental illness and other behavior. Compared with a control group who did not receive the special training the 80 officers showed increased interest in and sympathy for psychiatric problems.