The burden of heat-related mortality attributable to recent human-induced climate change.

Climate change affects human health; however, there have been no large-scale, systematic efforts to quantify the heat-related human health impacts that have already occurred due to climate change. Here, we use empirical data from 732 locations in 43 countries to estimate the mortality burdens associated with the additional heat exposure that has resulted from recent human-induced warming, during the period 1991-2018. Across all study countries, we find that 37.0% (range 20.5-76.3%) of warm-season heat-related deaths can be attributed to anthropogenic climate change and that increased mortality is evident on every continent. Burdens varied geographically but were of the order of dozens to hundreds of deaths per year in many locations. Our findings support the urgent need for more ambitious mitigation and adaptation strategies to minimize the public health impacts of climate change.

Seasonality of suicide: a multi-country multi-community observational study.

AIMS: We aimed to investigate the heterogeneity of seasonal suicide patterns among multiple geographically, demographically and socioeconomically diverse populations. METHODS: Weekly time-series data of suicide counts for 354 communities in 12 countries during 1986-2016 were analysed. Two-stage analysis was performed. In the first stage, a generalised linear model, including cyclic splines, was used to estimate seasonal patterns of suicide for each community. In the second stage, the community-specific seasonal patterns were combined for each country using meta-regression. In addition, the community-specific seasonal patterns were regressed onto community-level socioeconomic, demographic and environmental indicators using meta-regression. RESULTS: We observed seasonal patterns in suicide, with the counts peaking in spring and declining to a trough in winter in most of the countries. However, the shape of seasonal patterns varied among countries from bimodal to unimodal seasonality. The amplitude of seasonal patterns (i.e. the peak/trough relative risk) also varied from 1.47 (95% confidence interval [CI]: 1.33-1.62) to 1.05 (95% CI: 1.01-1.1) among 12 countries. The subgroup difference in the seasonal pattern also varied over countries. In some countries, larger amplitude was shown for females and for the elderly population (≥65 years of age) than for males and for younger people, respectively. The subperiod difference also varied; some countries showed increasing seasonality while others showed a decrease or little change. Finally, the amplitude was larger for communities with colder climates, higher proportions of elderly people and lower unemployment rates (p-values < 0.05). CONCLUSIONS: Despite the common features of a spring peak and a winter trough, seasonal suicide patterns were largely heterogeneous in shape, amplitude, subgroup differences and temporal changes among different populations, as influenced by climate, demographic and socioeconomic conditions. Our findings may help elucidate the underlying mechanisms of seasonal suicide patterns and aid in improving the design of population-specific suicide prevention programmes based on these patterns.

Exhaust ventilation in attached garages improves residential indoor air quality.

Previous research has shown that indoor benzene levels in homes with attached garages are higher than homes without attached garages. Exhaust ventilation in attached garages is one possible intervention to reduce these concentrations. To evaluate the effectiveness of this intervention, a randomized crossover study was conducted in 33 Ottawa homes in winter 2014. VOCs including benzene, toluene, ethylbenzene, and xylenes, nitrogen dioxide, carbon monoxide, and air exchange rates were measured over four 48-hour periods when a garage exhaust fan was turned on or off. A blower door test conducted in each garage was used to determine the required exhaust fan flow rate to provide a depressurization of 5 Pa in each garage relative to the home. When corrected for ambient concentrations, the fan decreased geometric mean indoor benzene concentrations from 1.04 to 0.40 µg/m3 , or by 62% (P<.05). The garage exhaust fan also significantly reduced outdoor-corrected geometric mean indoor concentrations of other pollutants, including toluene (53%), ethylbenzene (47%), m,p-xylene (45%), o-xylene (43%), and carbon monoxide (23%) (P<.05) while having no impact on the home air exchange rate. This study provides evidence that mechanical exhaust ventilation in attached garages can reduce indoor concentrations of pollutants originating from within attached garages.

Muscle growth in young horses: Effects of age, cytokines, and growth factors.

Success as equine athletes requires proper muscle growth in young horses. Muscle hypertrophy occurs through protein synthesis and the contribution of muscle satellite cells, which can be stimulated or inhibited by cytokines and growth factors present during exercise and growth. The hypotheses of this study were that 1) the LM area in young horses would increase over 1 yr, and 2) specific cytokines and growth factors (IL-1ß, IL-6, tumor necrosis factor [TNF]-α, IGF-I, and fibroblast growth factor [FGF]-2) would alter proliferation and differentiation of satellite cells isolated from young horses. Fourteen horses were divided into 3 age groups: weanlings ( = 5), yearlings to 2 yr olds ( = 4), and 3 to 4 yr olds ( = 5). The area, height, and subcutaneous fat depth of the LM were measured using ultrasonography, and BW and BCS were taken in October (Fall1), April (Spring), and October of the following year (Fall2). Satellite cells obtained from 10-d-old foals ( = 4) were cultured in the presence of IL-6, IL-1ß, TNF-α, IGF-I, or FGF-2 before evaluation of proliferation and differentiation. Data were analyzed using PROC MIXED in SAS. Body weight increased from Fall1 to Spring in weanlings ( < 0.001) and increased in all horses from Spring to Fall2 ( ≤ 0.02). Area and height of the LM increased over time ( < 0.001) and with increasing age group of horse ( ≤ 0.03), although there was no interaction of time and age ( > 0.61). There was a significant increase in LM area in all animals from Spring to Fall2 ( < 0.001) but not from Fall1 to Spring. Interleukin-6 and TNF-α decreased satellite cell proliferation by 14.9 and 11.5%, respectively ( ≤ 0.01). Interleukin-6 increased fusion 6.2%, whereas TNF-α decreased fusion 8.7% compared with control cells ( ≤ 0.001). Interleukin-1ß had no effect on proliferation ( = 0.32) but tended to decrease fusion ( = 0.06). Satellite cell proliferation was increased 28.8 and 73.0% by IGF-I and FGF-2, respectively ( < 0.0001). Differentiation was decreased 13.1% in the presence of FGF-2 but increased 3.5% in the presence of IGF-I ( ≤ 0.01). In summary, the LM area increases over the course of a year in young horses with the most growth occurring in summer. By stimulating or inhibiting proliferation and differentiation of satellite cells, IL-6, TNF-α, IL-1ß, IGF-I, and FGF-2 may alter muscle growth in young horses, thereby impacting athletic potential.

HORSE SPECIES SYMPOSIUM: The aging horse: Effects of inflammation on muscle satellite cells.

With improvements in care, the equine population is living longer, remaining active, and competing at increasingly older ages. Both advancing age and exercise result in increased concentrations of circulating and local cytokines, including IL-1ß, IL-6, and tumor necrosis factor-α. Athletic endeavors in the aged horse may further increase the proinflammatory environment in muscle, decreasing the ability to react appropriately to exercise. Poor response to exercise limits the athletic ability of geriatric horses, thus reducing their useful life span and potentially increasing the risk of injury. Satellite cells are muscle stem cells that reside adjacent to muscle fibers in skeletal muscle and are at least partially responsible for maintenance of muscle mass and muscle hypertrophy. In the adult animal, these cells normally exist in a quiescent state, becoming active, proliferating, and differentiating in response to specific stimuli. Growth factors and cytokines present during hypertrophy and following exercise affect satellite cell activity. Whereas the specific effects of cytokines on equine satellite cells are not well established, cytokines can influence satellite cell and myoblast proliferation and differentiation both positively and negatively. Understanding the effects of cytokines on equine satellite cell function will provide insight into the mechanisms responsible for the poor response to exercise in the aged horse. The proinflammatory environment in aged horses may inhibit exercise induced satellite cell activity, thereby diminishing exercise-induced hypertrophy. As more horses are surviving and competing into their 20s, more research is required to understand the response of these animals to exercise during normal aging.

Clinical and dermoscopic changes in common melanocytic nevi in school children: the Framingham school nevus study.

BACKGROUND: Nevi are potential precursors of malignant melanoma and are important risk factors for the development of the disease. Childhood may be a critical time for the formation and evolution of nevi. OBJECTIVES: To document the development of new nevi and to document the clinical and dermoscopic changes in index nevi in school children during a 1-year follow-up. METHODS: Digital photographs and dermoscopic images of the back of subjects were compared at baseline and 1-year follow-up to assess changes in nevi counts and in clinical and dermoscopic features of index nevi. RESULTS: Overall participation rate was 81% (42/52). 56.4% of study participants were found to have an increased number of nevi at 1-year follow-up. All nevi were small and clinically insignificant. Fifty percent of study participants were found to have dermoscopic changes in their index nevi at 1-year follow-up. Eighty-five percent of these changes were classified as subtle and 15.0% as obvious. CONCLUSIONS: A significant portion of students developed new nevi over the course of 1 year. Most index nevi remained stable in pattern and structure. Benign dermoscopic changes occurred in 50.0% of index nevi. However, none of the dermoscopically changed nevi revealed any major changes and the overall nevus pattern remained unchanged. The relevance of these changes is uncertain and further follow-up may elucidate their significance.

[Role of vitamin deficiency in pancytopenia in Djibouti. Findings in a series of 81 consectutive patients]. / Place des étiologies carentielles dans les pancytopénies à Djibouti a propos de 81 patients consécutifs.

The purpose of this study of patients with pancytopenia in Republic of Djibouti was to identify etiologic factors and attempt to define diagnostic and therapeutic strategies adapted to local conditions. Clinical, biological and radiological assessment was performed in 81 patients hospitalized for pancytopenia. There were 56 men and 25 women. Mean hemoglobin, leukocyte and platelet rates were 56,5 +/- 22,7 g/l, 2,1 +/- 0,7.g/l and 56,2 +/- 24,7 g/l respectively. Vitamin deficiency was the most common cause of pancytopenia (49%), followed by hypersplenism (9%), HIV infection (6%) and leishmaniasis (6%). Vitamin-deficient patients had significantly more severe anemia and thrombopenia and significantly higher mean corpuscular volume than patients with pancytopenia related to other causes. Hemoglobin rate lower than 40 g/L and platelet rate lower than 35 G/L showed a positive predictive values of 90% and 100% respectively for a vitamin deficient pancytopenia. Vitamin deficiency is the most frequent etiology of pancytopenia and causes the most severe cytopenia in Djibouti. Rapid vitamin supplementation after minimal etiologic assessment including a myelogram is an effective treatment strategy for this public health problem.

Factors associated with residual breast cancer after re-excision for close or positive margins.

BACKGROUND: Successful breast conservation surgery (BCS) requires complete tumor excision. Margin status of the initial specimen determines the need for additional surgery. We explored factors associated with residual cancer (RC) upon follow-up surgery in patients with close, positive, or undetermined margins following BCS. METHODS: A retrospective analysis of 276 patients with initial close, positive, or undetermined margins who underwent re-excision (RE) or mastectomy was conducted. All initial excisions were intended as definitive procedures. Chi-square analysis was used to identify factors that may predict RC. RESULTS: Of 276 patients, 87 had close, 168 had positive, and 21 had undetermined margins on initial excision. Of this group, 63% (175/276) had RC upon RE or mastectomy. Of positive-margin patients, 68% had RC, compared with 53% of close-margin and 67% of undetermined-margin patients (P = .006). Tumors >/=2 cm were more often associated with RC than smaller tumors (70.8% vs. 56.5%; P = .07). This association was strongest in positive-margin patients (P = .04). High tumor grade was associated with RC in all groups. RC linearly increased with the number of involved margins (P = .02). Specimen inking with multiple colors was associated with decreased risk of RC (P = .004). CONCLUSIONS: Over half of patients with involved or undetermined margins had RC upon RE or mastectomy. Positive and undetermined margins were more often associated with RC than close margins. Larger tumor size was associated with RC in patients with positive. Increasing tumor grade suggests a greater chance of detecting RC in all groups. Multiple involved margins led to a greater risk of RC.

Weight loss, dysphagia, and outcome in advanced dementia.

There has been much debate on the value and risks of long-term enteral feeding in patients with advanced dementia. A retrospective study was carried out on 47 patients with a primary diagnosis of dementia who died over a two-year period. All were inpatients in a nursing home or skilled nursing facility. Marked weight loss and dysphagia occurring in a specific pattern were found to be associated with death from pneumonia. These clinical features probably imply failure of basic homeostatic mechanisms. Patients showing this clinical pattern may be less likely to show benefits from long-term enteral feeding.

Postoperative adhesion formation after ovarian wedge resection with and without ovarian reconstruction in the rabbit.

A rabbit model was used to examine adhesion formation after ovarian wedge resection with and without reapproximation of the ovarian cortex. A wedge resection was completed on one ovary with a scalpel, and the ovarian cortex was reapproximated using microsurgical technique. In the contralateral ovary, a wedge resection was performed using the Nd:YAG laser and the cortex was left to heal by secondary intention. A second laparotomy was performed and the adhesion scores were compared between the two adnexa. In 17 of 19 rabbits, the adhesion score was greater on the side where ovarian reconstruction had been performed. No difference was noted in adhesion scores when, in our preliminary studies presented herein, laser and scalpel wedge resections were both followed by reapproximation of the cortex. These data have ramifications for conservative ovarian surgery performed both at laparotomy and laparoscopy.