Location on chromosome 15 of the gene defect causing Marfan syndrome

BACKGROUND. Marfan syndrome, "the founding member" of the heritable disorders of connective tissue, is a common autosomal dominant disorder with highly variable clinical manifestations in the skeletal, ocular, and cardiovascular systems. The fundamental defect leading to this disease has escaped definition despite decades of research efforts by several groups of investigators. METHODS AND RESULTS. Using linkage analyses with polymorphic markers of the human genome, we mapped the genetic defect to chromosome 15 in five families with Marfan syndrome. With three polymorphic markers we obtained definitive proof of linkage in these families (lod score = 3.92, theta = 0.0 +/- 0.11). The most probable location of the gene for the disease is currently D15S45 (lod score = 3.32, theta = 0.0 +/- 0.12). CONCLUSIONS. The chromosomal localization of the mutation in Marfan syndrome is a first step toward the isolation and characterization of the defective gene and serves as a diagnostic test in families in which cosegregation of these markers with the disease has been confirmed.     

Potential impact of the COVID-19 pandemic on the national and regional incidence,epidemiology and diagnostic testing of chlamydia and gonorrhoea in Sweden, 2020

The COVID-19 pandemic has challenged the societies and health care systems globally, and resulted in many social and physical distancing restrictions to limit the spread of SARS-CoV-2. These restrictions have also likely affected the frequency of intimate contacts and the spread of sexually transmitted infections (STIs). Compared to most other countries, Sweden especially in Spring-Autumn 2020 pursued mainly milder voluntary, that is, not mandatory enforced by laws, recommended restrictions and the impacts of these on society and spread of STIs remain largely unknown. We describe the potential impact of the COVID-19 pandemic on the national and regional incidence, epidemiology and diagnostic testing of chlamydia and gonorrhoea in Sweden in 2020. Compared to 2019, we found a significant decrease in incidence of chlamydia (?4.5%) and gonorrhoea (?17.5%), and in diagnostic testing (?10.5% for chlamydia, ?9.4% for gonorrhoea) in 2020. However, the decrease in chlamydia incidence, which has mainly been decreasing in the last 10 years, was not significant when compared with the average incidence in 2017–2019. The largest decrease in national incidence of both infections was observed among young and heterosexual patients, however, some Swedish regions showed an increased incidence, particularly of chlamydia. Increased “internet-based self-sampling” testing approach partly compensated for a decreased attendance at STI clinics. Studies, including sexual behaviour, prevention, reasons for attending STI health care, STIs in different anatomical sites and management of STIs, are required to elucidate the impact of COVID-19-associated social and physical distancing restrictions on sexual activity and the incidence and epidemiology of chlamydia and gonorrhoea in Sweden.     

The feasibility of alcohol screening and interventions in emergency care: a comparison of primary and specialised health care settings

Background: Implementation of alcohol screening and brief intervention in emergency departments is inadequate and the evidence base more mixed than in primary health care (PHC). This comparison study investigates the feasibility of alcohol screening and interventions by nurses in emergency departments, seven based in PHC and two in specialised health care clinics. The aim is to analyse barriers to implementation in these two contexts.

Methods: A questionnaire was used among emergency nurses in the Kymenlaakso hospital district in Finland. The response rate was 71% (N?=?112; PHC clinics n?=?42; specialised clinics n?=?38). The statistical differences in responses were analysed using the χ² test. Open-ended questions were analysed qualitatively.

Results: The nurses in specialised clinics treated patients with alcohol-attributable conditions/traumas more often than the nurses in PHC did (p?p?p?Conclusions: The results indicate an intervention paradox in the emergency care setting: compared to nurses in PHC clinics, nurses in specialised health care clinics work more often with intoxicated patients but they are less willing to implement alcohol screening and interventions. The findings highlight the need for institutional-level support in addition to capacity building among nurses.     

Regional glucose uptake and protein synthesis in isolated perfused rat hearts immediately after training and later

Summary The effect of 10 weeks of running training and termination of training on the regional distribution of cardiac glucose uptake and protein synthesis were studied in isolated perfused hearts in male rats. The left ventricular glucose uptake in hearts from sedentary rats was 1.87±0.14 mol/min per g protein (mean ± SE), being about 30% higher in the subendocardial than in the subepicardial layer (p<0.05). The gradient of left ventricular glucose uptake was similar to the controls in the rats retired from training, but was absent in the trained animals. The altered transmural glucose uptake probably reflects differences in the adaptive response of various myocardial muscle layers to a long-term intermittent increase in cardiac work load. Phenylalanine incorporation was evenly distributed through the left ventricle in all the groups, but was lowered in the left and right ventricles of the trained rats. Phenylalanine incorporation returned to the control level 5 weeks after the cessation of training.     

Physical exercise increases adult hippocampal neurogenesis in male rats provided it is aerobic and sustained

Key points

• Aerobic exercise, such as running, enhances adult hippocampal neurogenesis (AHN) in rodents.
• Little is known about the effects of high‐intensity interval training (HIT) or of purely anaerobic resistance training on AHN.
• Here, compared with a sedentary lifestyle, we report a very modest effect of HIT and no effect of resistance training on AHN in adult male rats.
• We found the most AHN in rats that were selectively bred for an innately high response to aerobic exercise that also run voluntarily and increase maximal running capacity.
• Our results confirm that sustained aerobic exercise is key in improving AHN.

Abstract

Aerobic exercise, such as running, has positive effects on brain structure and function, such as adult hippocampal neurogenesis (AHN) and learning. Whether high‐intensity interval training (HIT), referring to alternating short bouts of very intense anaerobic exercise with recovery periods, or anaerobic resistance training (RT) has similar effects on AHN is unclear. In addition, individual genetic variation in the overall response to physical exercise is likely to play a part in the effects of exercise on AHN but is less well studied. Recently, we developed polygenic rat models that gain differentially for running capacity in response to aerobic treadmill training. Here, we subjected these low‐response trainer (LRT) and high‐response trainer (HRT) adult male rats to various forms of physical exercise for 6–8 weeks and examined the effects on AHN. Compared with sedentary animals, the highest number of doublecortin‐positive hippocampal cells was observed in HRT rats that ran voluntarily on a running wheel, whereas HIT on the treadmill had a smaller, statistically non‐significant effect on AHN. Adult hippocampal neurogenesis was elevated in both LRT and HRT rats that underwent endurance training on a treadmill compared with those that performed RT by climbing a vertical ladder with weights, despite their significant gain in strength. Furthermore, RT had no effect on proliferation (Ki67), maturation (doublecortin) or survival (bromodeoxyuridine) of new adult‐born hippocampal neurons in adult male Sprague–Dawley rats. Our results suggest that physical exercise promotes AHN most effectively if the exercise is aerobic and sustained, especially when accompanied by a heightened genetic predisposition for response to physical exercise.

Abbreviations

AHN

adult hippocampal neurogenesis

BDNF

brain‐derived neurotrophic factor

BrdU

bromodeoxyuridine

HIT

high‐intensity interval training

HRT

high‐response trainer

LRT

low‐response trainer

RW

running wheel

Sed

sedentary

TBS

Tris‐buffered saline

V˙O2max

maximal oxygen uptake