A highly virulent variant of HIV-1 circulating in the Netherlands

We discovered a highly virulent variant of subtype-B HIV-1 in the Netherlands. One hundred nine individuals with this variant had a 0.54 to 0.74 log₁₀ increase (i.e., a ~3.5-fold to 5.5-fold increase) in viral load compared with, and exhibited CD4 cell decline twice as fast as, 6604 individuals with other subtype-B strains. Without treatment, advanced HIV-CD4 cell counts below 350 cells per cubic millimeter, with long-term clinical consequences-is expected to be reached, on average, 9 months after diagnosis for individuals in their thirties with this variant. Age, sex, suspected mode of transmission, and place of birth for the aforementioned 109 individuals were typical for HIV-positive people in the Netherlands, which suggests that the increased virulence is attributable to the viral strain. Genetic sequence analysis suggests that this variant arose in the 1990s from de novo mutation, not recombination, with increased transmissibility and an unfamiliar molecular mechanism of virulence.

Single Shot Characterization of High Transformer Ratio Wakefields in Nonlinear Plasma Acceleration

Plasma wakefields can enable very high accelerating gradients for frontier high energy particle accelerators, in excess of 10  GeV/m. To overcome limits on single stage acceleration, specially shaped drive beams can be used in both linear and nonlinear plasma wakefield accelerators (PWFA), to increase the transformer ratio, implying that the drive beam deceleration is minimized relative to acceleration obtained in the wake. In this Letter, we report the results of a nonlinear PWFA, high transformer ratio experiment using high-charge, longitudinally asymmetric drive beams in a plasma cell. An emittance exchange process is used to generate variable drive current profiles, in conjunction with a long (multiple plasma wavelength) witness beam. The witness beam is energy modulated by the wakefield, yielding a response that contains detailed spectral information in a single-shot measurement. Using these methods, we generate a variety of beam profiles and characterize the wakefields, directly observing transformer ratios up to R=7.8. Furthermore, a spectrally based reconstruction technique, validated by 3D particle-in-cell simulations, is introduced to obtain the drive beam current profile from the decelerating wake data.

Bariatric fellowship positively influences early outcomes for laparoscopic Roux-en-Y gastric bypass surgery over seven years of independent practice

Introduction Laparoscopic Roux-en-Y gastric bypass (LRYGB) is technically demanding and has an associated learning curve. We published previously that bariatric fellowship reduces the learning curve of primary LRYGB and improves patient outcomes after one year of independent practice. However, the long-term effect of fellowship is unknown. We therefore aimed to compare the 30-day outcomes of LRYGB between the first year of a surgeon's independent practice with the subsequent six years. Materials and methods A prospective database of patients undergoing primary LRYGB under a single surgeon from March 2010 until February 2017 was analysed. Two groups were studied: first year (< 1 year) and the subsequent six years (≥ 1 year) of independent practice. Patient demographics, length of hospital stay, conversion to open surgery, perioperative complications and mortality were compared. Results Among 279 eligible patients, 74 (26.5%) were in the < 1 year group and 205 (73.5%) in ≥ 1 year group. The preoperative risk scores, American Society of Anesthesiologists (ASA) grade, P = 0.00; obesity surgery mortality risk score (OS-MRS), P = 0.04) were significantly higher in ≥ 1 year group. There was no significant difference in perioperative outcomes (length of stay, P = 0.38; total complications, P = 0.20; readmissions, P = 1.00; reoperations, P = 0.60) between the two groups. Conclusions Bariatric fellowship reduces the learning curve for LRYGB and helps to achieve excellent outcomes in the first and subsequent years of independent practice. The higher risk profile of ≥ 1 year group did not equate to an increase in complications, suggesting that experience and standardisation may help in handling complex cases. To our knowledge, this represents the only such study in the literature.

The challenge of mastitis

The process of lactation and feeding, referred to by some as the final stage of labour is remarkably successful. This phase of infant care has been subjected to considerable evolutionary pressure since the earliest mammals, reptiles and birds diversified. It has allowed thousands of species to occupy a vast range of ecological niches. Yet a significant complication of breast feeding remains inflammation of the lactating tissue: the pathology of mastitis. Mastitis rarely develops outside lactation, although it may affect individuals at any age in relation to congenital lesions such as duct ectasia, chronic disseminated infections such as tuberculosis, or during granulomatous, autoimmune or malignant processes. The immunology and consequences of mastitis as well as its impact on vertical transmission of infection require careful examination.

Striae formation in two HIV-positive persons receiving protease inhibitors

Steroidal side effects such as "buffalo hump" and visceral abdominal fat accumulation have been reported in association with protease inhibitors. We report two cases of severe disfiguring striae formation in patients with HIV who recently started indinavir therapy. These changes occurred within 3 months of starting treatment.

Neurodegeneration induced by MoMuLV-ts1 and increased expression of Fas and TNF-alpha in the central nervous system

Infection of neonatal mice with ts1, the neuropathogenic mutant of the Moloney murine leukemia virus, results in motor neuronal death in the brainstem and the spinal cord, with gliosis and demyelination, but no inflammatory cell infiltration into the CNS. To evaluate the possible mechanism(s) of ts1-induced neuropathogenesis, we measured CNS expression of cytokines and cell death-related genes in ts1-infected mice with neurological signs and compared with control uninfected mice. In the brainstem, the expression of Fas and tumor necrosis factor alpha (TNF-alpha) was increased in the ts1-infected mice. Both TNF-alpha and Fas were detected in astrocytes, and Fas was also detected in neurons in the brainstem. Some TNF-alpha-immunolabeled cells also appeared to be microglial cells. Most Fas-positive cells, including astrocytes and neurons, showed cytoplasmic vacuolization and other degenerative changes. In addition, Fas ligand-immunolabeled cells were also detected in sites where spongiform degeneration occurred. This study suggests that neural cell death in ts1-induced neurodegeneration is likely due to Fas- and TNF-alpha-mediated cell death mechanisms.

The American Stop Smoking Intervention Study for cancer prevention: an overview

The American Stop Smoking Intervention Study (ASSIST) is a programme to implement proven interventions in 17 states across the United States. ASSIST applies all that we have learned in 10 years of research on tobacco use prevention and control. The goal of this seven-year project is to reduce the prevalence of smoking and cigarette consumption in the ASSIST states. The scientific basis for ASSIST is described, followed by a general description of the project and its current status in the 17 targeted states.

Promoting worksite smoking control policies and actions: the Community Intervention Trial for Smoking Cessation (COMMIT) experience. The COMMIT Research Group

BACKGROUND

As an important aspect of the COMMIT trial, worksite smoking-control consultations and supports were provided to employers in 11 diverse, moderate-sized communities. After a 4-year intervention period (1989-1992), impacts on worksite policies, support resources for smokers, and employee perceptions were assessed in these communities and in 11 matched Comparison communities.

METHODS

Data from two surveys are reported here. In each of the 22 COMMIT communities, a sample of worksites within each of four size strata were surveyed to determine worksite policies, activities, and resources regarding smoking. Data from employees were obtained from independent community-wide surveys of community residents.

RESULTS

Overall, 44% of the worksites surveyed reported having smoke-free policies, with no differences between Intervention and Comparison communities. Thirty-seven percent of Intervention community work-sites reported offering smoking cessation resources or assistance for employees during the period of the study, compared to 31% of Comparison community worksites (P = 0.04). Employees in Intervention communities, relative to those in Comparison communities, reported greater awareness of stop-smoking resources, but equivalent increases in worksite smoking bans.

CONCLUSION

Although the level of worksite smoking-cessation activities was higher in Intervention than in Comparison communities, there remains a substantial need to increase the level of such activities and to integrate such activities with restrictive smoking policies.

Chickenpox pneumonia: experience with antiviral treatment

Of 13 patients with chickenpox pneumonia (12 of them adults) treated during 1979-87, 10 received antiviral drugs--nine acyclovir and one vidarabine. Three died despite intensive treatment. Serious secondary infections occurred in six cases. There were no clear indications that antiviral treatment altered the natural history of the condition. Acyclovir may at present be used too late in the course of chickenpox pneumonia to alter its outcome.