Rafael Alis

Cortical neurons are specified during embryonic development but often only acquire their mature properties at relatively late stages of postnatal development. This delay in terminal differentiation is particularly prominent for fast-spiking parvalbumin-expressing (PV+) interneurons, which play critical roles in regulating the function of the cerebral cortex. We found that the maturation of PV+ interneurons is triggered by neuronal activity and mediated by the transcriptional cofactor peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α). Developmental loss of PGC-1α prevents PV+ interneurons from acquiring unique structural, electrophysiological, synaptic, and metabolic features and disrupts their diversification into distinct subtypes. PGC-1α exerts its function as a master regulator of the differentiation of PV+ interneurons by directly controlling gene expression through a transcriptional complex that includes ERRγ and Mef2c. Our results uncover a molecular switch that translates neural activity into a specific transcriptional program promoting the maturation of PV+ interneurons at the appropriate developmental stage.

We aimed to evaluate the utility of a submaximal heart rate recovery (HRR) test to monitor changes in cardiac fitness after aerobic training. Twenty healthy subjects were assigned to a control (n=10) or a training (n=10) group. Subjects in the training group performed 8 weeks of bicycle training, followed by 8 weeks of detraining. HRR was assessed after exercises at 65% and 80% HRmax. The HRR test was performed at weeks 0 (W0), 4 (W4), 8 (W8) and 16 (W16) in the training group and at W0 and W8 in the control group. HRR indices changed in response to training and detraining. Absolute HR recovery at 60, 120 and 180 seconds after exercise increased at both exercise intensities at W8 of training (p0.05, W16 vs. W0). Time constants of fast HRR recovery (<1 min) changed with training (p0.05, W16 vs. W0), but only at 65% HRmax. At the end of the 3-minute recovery period, the predicted HR value (A0) and the HR recovered (Amax) from the mono-exponential analysis changed with training (p0.05. W16 vs. W0). We conclude that this novel submaximal HRR test is highly sensitive for monitoring cardiac fitness during training and detraining in healthy people. Since this test is simple, inexpensive, and the data are reliable and easy to analyze, we hope that it may be of interest to the sports science community.

Objective: To report on 2 patients with alcoholic cirrhosis who were treated with transjugular intrahepatic portosystemic shunt (TIPS) placement. Clinical Presentation and Intervention: The 2 patients had a history of alcoholic cirrhosis, and TIPS surgery was performed on them. In both cases, 4 months after TIPS placement, proteinuria was observed along with histological alterations characteristic of immune complex membranoproliferative glomerulonephritis (MPGN). Conclusion: The TIPS in one patient was successful without immediate complications, while the other patient was referred for a combined liver-kidney transplant. In both cases, immune complex MPGN might have developed after TIPS placement probably due to a reduced immune complex clearance.

Article: Alpha-amylase serum levels in professional soccer players are not related with physical fitness - The Journal of Sports Medicine and Physical Fitness 2017 March;57(3):214-8 - Minerva Medica - Journals

Myostatin (MSTN) and α-actinin-3 (ACTN3) genes are potentially associated with preservation of muscle mass and oxidative capacity, respectively. To explore the possible role of these genes in exceptional longevity (EL), the allele/genotype frequency distribution of two polymorphisms in MSTN (rs1805086, K153R) and ACTN3 (rs1815739, R577X) was studied in Japanese centenarians of both sexes (n = 742) and healthy controls (n = 814). The rs1805086 R-allele (theoretically associated with muscle mass preservation at the expense of oxidative capacity) was virtually absent in the two groups, where genotype distributions were virtually identical. Likewise, no differences in allele (p = 0.838 (women); p = 0.193 (men); p = 0.587 (both sexes)) or genotype distribution were found between groups for ACTN3 rs1815739 (p = 0.975 (women), p = 0.136 (men), p = 0.752 (both sexes)). Of note, however, the frequency of the rs1805086 R-allele observed here is the lowest been reported to date whereas that of the ‘highly oxidative/efficient’ rs1815739 XX genotype in Japanese male centenarians (33.3%) or supercentenarians of both sexes (≥110 years) are the highest (32.6%), for a non-American population. No definite conclusions can be inferred in relation to EL owing to its lack of association with both rs1815739 and rs1805086. However, it cannot be excluded that these gene variants could eventually be related to a “healthy” metabolic phenotype in the Japanese population. Further research might determine if such metabolic profile is among the factors that can potentially predispose these individuals to live longer than Caucasians and what genetic variants might be actually involved.

In this reported clinical case, a healthy and well-trained male subject [aged 37 years, maximal oxygen uptake (V[Combining Dot Above]O2max) 64 mL·kg−1·min−1] ran for 23 hours and 35 minutes covering 160 km (6.7 km/h average running speed). The analysis of hematological and biochemical parameters 3 days before the event, just after termination of exercise, and after 24 and 48 hours of recovery revealed important changes on muscle and liver function, and hemolysis. The analysis of urine sediments showed an increment of red and white blood cells filtrations, compatible with transient nephritis. After 48 hours, most of these alterations were recovered. Physicians and health professionals who monitor such athletic events should be aware that these athletes could exhibit transient symptoms compatible with severe pathologies and diseases, although the genesis of these blood and urinary abnormalities are attributable to transient physiological adaptations rather to pathological status.