Reproduction and thermoregulation in Peromyscus: Effects of chronic short days

Seven groups of laboratory reared Connecticut P. leucopus were exposed to a 9L:15D photoperiod for either 6, 9, 12, 20, 25, 32, or 36 weeks. An eighth group was maintained on 16L:8D. During the final 6 weeks all mice were cold exposed (13°C). Substantial reproductive regression occurred in females following 6 weeks exposure to 9L:15D relative to 16L:8D animals. In males, a slight decrease in testicular weight occurred following 6 weeks on 9L:15D; this effect was pronounced by 9 weeks, along with a decrease in seminal vesicle weight. Reproductive recrudescence occurred in females by week 32 and in males by week 36. Between 10 and 12 weeks on 9L:15D mice exhibited increases in nesting, incidence of daily torpor, and presence of the winter molt. These increases persisted through 36 weeks on 9L:15D. An increase in the interscapular brown fat pad occurred between 12 and 25 weeks. Reproductive and thermoregulatory characters respond differently to prolonged exposure to a short day photoperiod in this species.     

Autoradiographic localization of kappa opiate receptors in CNS taste and feeding areas

Recent evidence suggests that kappa opiate receptors may play a key role in the regulation of appetite. Such evidence implies that kappa receptors might be localized within specific brain areas known to regulate ingestive behaviors. On the basis of this implication we employed an in vitro film autoradiographic technique using 3H-ethylketocyclazozine as ligand to identify putative kappa receptors within CNS "taste" nuclei and surrounding areas. Coronal cryostat sections of rat brain were incubated with ligand in the presence of D-Ala2, D-Leu5-enkephalin (DADLE) and morphine, apposed to LKB Ultrofilm for 60 days, processed and kappa receptor densities evaluated with the aid of a hand held photometer and video image analyzer. Highest kappa receptor densities were found within various gustatory and feeding sites including the rostral pole of the nucleus of the solitary tract, parabrachial nuclei, ventral posterior and medial portions of the thalamus, medial hypothalamus, medial nuclei of the amygdala and bed nucleus of the stria terminalis. Various other midline and medial limbic areas also showed significant kappa densities.     

Kidney transplant program waitlisting rate as a metric to assess transplant access

Kidney transplant program performance in the United States is commonly measured by posttransplant outcomes. Inclusion of pretransplant measures could provide a more comprehensive assessment of transplant program performance and necessary information for patient decision-making. In this study, we propose a new metric, the waitlisting rate, defined as the ratio of patients who are waitlisted in a center relative to the person-years referred for evaluation to a program. Furthermore, we standardize the waitlisting rate relative to the state average in Georgia, North Carolina, and South Carolina. The new metric was used as a proof-of-concept to assess transplant-program access compared to the existing transplant rate metric. The study cohorts were defined by linking 2017 United States Renal Data System (USRDS) data with transplant-program referral data from the Southeastern United States between January 1, 2012 and December 31, 2016. Waitlisting rate varied across the 9 Southeastern transplant programs, ranging from 10 to 22 events per 100 patient-years, whereas the program-specific waitlisting rate ratio ranged between 0.76 and 1.33. Program-specific waitlisting rate ratio was uncorrelated with the transplant rate ratio (r = −.15, 95% CI, −0.83 to 0.57). Findings warrant collection of national data on early transplant steps, such as referral, for a more comprehensive assessment of transplant program performance and pretransplant access.     

Public discourse and policy change: Absence of harm from increased oversight and transparency in OPO performance

The Centers for Medicare and Medicaid Services announced changes to the Final Rule for organ procurement organizations (OPOs) in November 2020, after a 23-month period of public debate. One concern among transplant stakeholders was that public focus on OPO underperformance would harm deceased donation. Using CDC-WONDER data, we studied whether donation performance dropped during the era of public debate about OPO reform (December 2018–February 2020). Overall OPO performance as measured relative to cause, age, and location-consistent deaths rose by 12.3% in 2019, compared to a median annual change of 2.5% 2009–2019. Organ recoveries exceeded seasonally adjusted forecasts by 4.2% in the first half of 2019, by 8.1% following the Executive Order issuing a mandate for OPO metric reform, and by 14.1% between the Notice of Public Rule Making and the onset of COVID-19-related systemic disruptions. We describe changes in donor phenotype in the period of increased performance; improvement was greatest for older and donation after cardiac death (DCD) donors, and among decedents who did not have a drug-related mechanism of death. In summary, performance during an era of intense public debate and proposed regulatory changes yielded 692 additional donors over expectations, and no detriment to organ donation was observed.     

Triplications of chromosome 1p36.3, including the genes GABRD and SKI,are associated with a developmental disorder and a facial gestalt

Triplication of chromosomal region 1p36.3 is a rare genomic rearrangement. In this report, we delineate the phenotypic spectrum associated with 1p36.3 triplications. We describe four patients with microtriplications of variable size, but with a strong phenotypic overlap, and compare them to previously described patients with an isolated triplication or duplication of this region. The 1p36.3 triplication syndrome is associated with a distinct phenotype, characterized by global developmental delay, moderate intellectual disability, seizures, behavioral problems, and specific facial dysmorphic features, including ptosis, hypertelorism, and arched eyebrows. The de novo occurrence of these microtriplications demonstrates the reduced reproductive fitness associated with this genotype, in contrast to 1p36.3 duplications which are mostly inherited and can be associated with similar facial features but with a less severe developmental phenotype. The shared triplicated region encompasses four disease-related genes of which GABRD and SKI are most likely to contribute to the phenotype.     

The Low-Grade Lymphomas

The lymphomas comprise a spectrum of diseases with vast variation in histologic appearance, presentation and natural history, and response to therapy. At one end of the spectrum are the low-grade lymphomas (LGLs), indolent malignancies characterized by paradox. Despite an exceedingly low growth fraction, the LGLs are usually extensive at presentation, and yet they rarely involve privileged sites, such as cortical bone or central nervous system, and rarely destroy adjacent tissue. They are exquisitely responsive to many different therapeutic interventions, but responses to most agents are transient and similar. Finally, although survival of most LGL patients is measured in years, the course of the disease is punctuated by both transient and long-term responses to treatment, and also by spontaneous regression and transformation to more aggressive lymphomas in the absence of therapy, rendering the evaluation of the true impact of treatment quite difficult. The focus of this review is on the management of the LGLs, in particular the role of radiotherapy.     

Comparison of ambulatory and inpatient experiences in five specialties

This study compared medical student evaluations of ambulatory and inpatient components of third-year clerkships in internal medicine, obstetrics/gynaecology, paediatrics, psychiatry, and surgery. Seventy-two students completed evaluation questionnaires at the conclusion of each of five clerkships over 12 months. Although ambulatory and inpatient evaluations were comparable across all five specialties in several areas, ambulatory education was rated more favorably in scheduling, clear definition of student roles and responsibilities, appropriate supervision, timely and constructive feedback, being welcomed, and working in a non-threatening environment.Student feedback thus implied that ambulatory experiences were comparable to, or better than, inpatient experiences and suggests areas for improving clinical education in inpatient settings.     

Drinking water source and chlorination byproducts in Iowa. III. Risk of brain cancer.

The authors conducted a population-based case-control study in Iowa of 375 brain cancer patients and 2,434 controls. A postal questionnaire was used to gather information on lifetime residential history, sources of drinking water, beverage intake, and other potential risk factors. Exposure to chlorination byproducts in drinking water was estimated by combining questionnaire data with historical information from water utilities and trihalomethane levels in recent samples. The analysis included 291 cases (77.6%) and 1,983 controls (81.5%), for whom water quality information was available for at least 70% of lifetime years. Proxies represented 74.4% of cases. The mean number and mean duration of places of residence were comparable between direct and proxy respondents, suggesting little contribution to bias. After multivariate adjustment, odds ratios for brain cancer were 1.0, 1.1, 1.6, and 1.3 for exposure to chlorinated surface water of 0, 1-19, 20-39, and > or =40 years (p trend = 0.1). Among men, odds ratios were 1.0, 1.3, 1.7, and 2.5 (p trend = 0.04), and among women, 1.0, 1.0, 1.6, and 0.7 (p trend = 0.7)). Similar findings were found with estimates of average lifetime level of trihalomethanes. The association was stronger among men with above-median tap water consumption. These observations deserve further attention, especially in view of increasing glioma rates.     

The social class determinants of income inequality and social cohesion.

The authors argue that Wilkinson's model omits important variables (social class) that make it vulnerable to biases due to model mis-specification. Furthermore, the culture of inequality hypothesis unnecessarily "psychopathologizes" the relatively deprived while omitting social determinants of disease related to production (environmental and occupational hazards) and the capacity of the relatively deprived for collective action. In addition, the hypothesis that being "disrespected" is a fundamental determinant of violence has already been refuted. Shying away from social mechanisms such as exploitation, workplace domination, or classist ideology might avoid conflict but reduce the income inequality model to a set of useful, but simple and wanting associations. Using a nonrecursive structural equation model that tests for reciprocal effects, the authors show that working-class position is negatively associated with social cohesion but positively associated with union membership. Thus, current indicators of social cohesion use middle-class standards for collective action that working-class communities are unlikely to meet. An erroneous characterization of working-class communities as noncohesive could be used to justify paternalistic or punitive social policies. These criticisms should not detract from an acknowledgment of Wilkinson's investigations as a leading empirical contribution to reviving social epidemiology at the end of the century.