Background
Due to the SARS-CoV2 pandemic, medical face masks are widely recommended for a large number of individuals and long durations. The effect of wearing a surgical and a FFP2/N95 face mask on ...cardiopulmonary exercise capacity has not been systematically reported.
Methods
This prospective cross-over study quantitated the effects of wearing no mask (nm), a surgical mask (sm) and a FFP2/N95 mask (ffpm) in 12 healthy males (age 38.1 ± 6.2 years, BMI 24.5 ± 2.0 kg/m
2
). The 36 tests were performed in randomized order. The cardiopulmonary and metabolic responses were monitored by ergo-spirometry and impedance cardiography. Ten domains of comfort/discomfort of wearing a mask were assessed by questionnaire.
Results
The pulmonary function parameters were significantly lower with mask (forced expiratory volume: 5.6 ± 1.0 vs 5.3 ± 0.8 vs 6.1 ± 1.0 l/s with sm, ffpm and nm, respectively;
p
= 0.001; peak expiratory flow: 8.7 ± 1.4 vs 7.5 ± 1.1 vs 9.7 ± 1.6 l/s;
p
< 0.001). The maximum power was 269 ± 45, 263 ± 42 and 277 ± 46 W with sm, ffpm and nm, respectively;
p
= 0.002; the ventilation was significantly reduced with both face masks (131 ± 28 vs 114 ± 23 vs 99 ± 19 l/m;
p
< 0.001). Peak blood lactate response was reduced with mask. Cardiac output was similar with and without mask. Participants reported consistent and marked discomfort wearing the masks, especially ffpm.
Conclusion
Ventilation, cardiopulmonary exercise capacity and comfort are reduced by surgical masks and highly impaired by FFP2/N95 face masks in healthy individuals. These data are important for recommendations on wearing face masks at work or during physical exercise.
Abstract
There is increasing evidence of cardiac involvement post-SARS-CoV-2 infections in symptomatic as well as in oligo- and asymptomatic athletes. This study aimed to characterize the possible ...early effects of SARS-CoV-2 infections on myocardial morphology and cardiopulmonary function in athletes. Eight male elite handball players (27 ± 3.5 y) with past SARS-CoV-2 infection were compared with four uninfected teammates (22 ± 2.6 y). Infected athletes were examined 19 ± 7 days after the first positive PCR test. Echocardiographic assessment of the global longitudinal strain under resting conditions was not significantly changed (− 17.7% vs. − 18.1%). However, magnetic resonance imaging showed minor signs of acute inflammation/oedema in all infected athletes (T2-mapping: + 4.1 ms,
p
= 0.034) without reaching the Lake-Louis criteria. Spiroergometric analysis showed a significant reduction in VO2max (− 292 ml/min, − 7.0%), oxygen pulse (− 2.4 ml/beat, − 10.4%), and respiratory minute volume (VE) (− 18.9 l/min, − 13.8%) in athletes with a history of SARS-CoV2 infection (
p
< 0.05, respectively). The parameters were unchanged in the uninfected teammates. SARS-CoV2 infection caused impairment of cardiopulmonary performance during physical effort in elite athletes. It seems reasonable to screen athletes after SARS-CoV2 infection with spiroergometry to identify performance limitations and to guide the return to competition.
It is increasingly being appreciated that GABAA receptor subtypes, through their specific regional, cellular and subcellular localization, are linked to distinct neuronal circuits and consequently ...serve distinct functions. GABAA receptor subtype-selective drugs are therefore expected to provide novel pharmacological profiles. Receptors containing the alpha1 subunit mediate sedation and serve as targets for sedative hypnotics. Agonists selective for alpha2- and/or alpha3-containing GABAA receptors have been shown to provide anxiolysis without sedation in preclinical models, whereas inverse agonists selective for alpha5-containing GABAA receptors provide memory enhancement. Agonists selective for alpha3-containing GABAA receptors might be suitable for the treatment of deficits in sensorimotor processing in psychiatric disorders. Thus, a new pharmacology based on GABAA receptor subtype-specific actions is emerging.
Perforation of the colon is considered to be one of the most serious complications of flexible endoscopy. The over-the-scope clip system (OTSC) has previously been shown to close small colonic ...perforations effectively. The aim of this randomized controlled porcine study was to compare acute closure strengths between the novel 11-mm over-the-scope-clip and surgical closure for large colonic perforations.
In 24 anesthetized domestic pigs, an 18-mm sigmoid perforation was created endoscopically using a needle knife and dilating balloon. The animals were randomly assigned to undergo either open surgical repair (n = 12) or endoscopic closure using the OTSC system (n = 12). Pressurized leak tests were performed during necropsy.
Mean time to perform the incision in the sigmoid colon and obtain peritoneal access was 5.5 minutes (range 3-12; SD +/- 2.5). Mean time for endoscopic closure was 6.8 minutes (range 3-14; SD +/- 3). At necropsy, all OTSC and surgical closures demonstrated complete sealing of colotomy sites. In one case peritoneum and in a second case adjacent small intestine were found incorporated into the OTSC closure. No other complications occurred. Pressurized leak tests revealed a mean burst pressure of 62.8 mmHg (range 18-112; SD 35.7) for OTSC closures and 67.4 mmHg (range 30-90; SD 19) for sutured closure. No significant differences in burst pressures were noted between the OTSC closures and surgical repair.
Closure of acute perforations using the OTSC system is comparable to surgical closure in a nonsurvival porcine model.
A new benzodiazepine pharmacology Möhler, H; Fritschy, J M; Rudolph, U
The Journal of pharmacology and experimental therapeutics
300, Številka:
1
Journal Article
Recenzirano
Classical benzodiazepine drugs are in wide clinical use as anxiolytics, hypnotics, anticonvulsants, and muscle relaxants. They act by enhancing the gamma-aminobutyric acid(A) (GABA(A)) receptor ...function in the central nervous system. The pharmacological relevance of the multitude of structurally diverse GABA(A) receptor subtypes has only recently been identified. Based on an in vivo point mutation strategy, alpha(1)-GABA(A) receptors were found to mediate sedation, anterograde amnesia, and part of the seizure protection, whereas alpha(2)-GABA(A) receptors, but not alpha(3)-receptors, mediate anxiolysis. Rational drug targeting to specific receptor subtypes has now become possible. Only restricted neuronal networks will be modulated by the new subtype-selective drugs. Promising new anxiolytics have already been developed. A new pharmacology of the benzodiazepine site is on the horizon.
Surgical interventions like skin incisions trigger withdrawal reflexes which require motor neurones and local circuit interneurones in the spinal ventral horn. This region plays a key role in ...mediating immobilizing properties of the GABAergic anaesthetic propofol. However, it is unclear how propofol modulates GABA(A) receptors in the spinal ventral horn and whether tonic or phasic inhibition is involved.
Organotypic spinal cord tissue slices were prepared from mice. Whole-cell recordings were performed for quantifying effects of propofol on GABA(A) receptor-mediated phasic transmission and tonic conductance.
Propofol increased GABAergic phasic transmission by a prolongation of the decay time constant in a concentration-dependent manner. The amount of the charge transferred per inhibitory post-synaptic current, described by the area under the curve, was significantly augmented by 1 µM propofol (P<0.01). A GABA(A) receptor-mediated tonic current was not induced by 1 µM propofol but at a concentration of 5 µM (P<0.05).
Propofol depresses ventral horn interneurones predominantly by phasic rather than by tonic GABA(A) receptor-mediated inhibition. However, the present results suggest that the involvement of a tonic inhibition might contribute to the efficacy of propofol to depress nociceptive reflexes at high concentrations of the anaesthetic.
This paper outlines the preliminary investigation of a pilot-scale constructed wetland, in which three native plant species (
Scirpus littoralis
,
Cyperus involucratus
and
Posidoniaceae
) are ...utilized, for the treatment of shrimp farm effluents. The experimental results show good TKN and TAN removal efficiency rates (41–63 and 41–61%), compared to the figures for COD, BOD and TP being moderate (19–31, 22–37 and 32–41%). In greater detail, the removal efficiency rates slightly increased during the first 30 days of the operation before declining when the HLR was increased. This study is a part of a project that aims to reduce the water consumption of current shrimp cultures in the Mekong Delta region in Vietnam. The results of this study indicate that the model can be upscaled in the next phase. Finally, to obtain treated wastewater at higher safety level, additional modules, such as membrane filtration or adsorption, might be installed.
In mammals, olfactory bulb granule cells (GCs) are generated throughout life in the subventricular zone. GABAergic inputs onto newborn neurons likely regulate their maturation, but the details of ...this process remain still elusive. Here, we investigated the differentiation, synaptic integration, and survival of adult-born GCs when their afferent GABAergic inputs are challenged by conditional gene targeting. Migrating GC precursors were targeted with Cre-eGFP-expressing lentiviral vectors in mice with a floxed gene encoding the GABA(A) receptor α2-subunit (i.e., Gabra2). Ablation of the α2-subunit did not affect GC survival but dramatically delayed their maturation. We found a reduction in postsynaptic α2-subunit and gephyrin clusters accompanied by a decrease in the frequency and amplitude of GABAergic postsynaptic currents beginning ∼14 d post-injection (dpi). In addition, mutant cells exhibited altered dendritic branching and spine density. Spine loss appeared with mislocation of glutamatergic synapses on dendritic shafts and a reduction of spontaneous glutamatergic postsynaptic currents, underscoring the relevance of afferent GABAergic transmission for a proper synaptic integration of newborn GCs. To test the role of GABAergic signaling during much early stages of GC maturation, we used a genetic strategy to selectively inactivate Gabra2 in precursor cells of the subventricular zone. In these mice, labeling of newborn GCs with eGFP lentiviruses revealed similar morphological alterations as seen on delayed Gabra2 inactivation in migrating neuroblasts, with reduced dendritic branching and spine density at 7 dpi. Collectively, these results emphasize the critical role of GABAergic synaptic signaling for structural maturation of adult-born GCs and formation of glutamatergic synapses.
The province of Thai Binh in Vietnam has undergone a recent rapid industrialization and urbanization phase. The living standards of the locality and better economic climate are achieved, yet at the ...expense of a certain risk of pollution of the environment. With the goal of sustainable development, the environmental situation of the region was regularly investigated by corresponding authorities. Additionally, it was researched to figure out new methods to monitor these qualities in an efficient and cost-effective manner. In this study, aimed at being used as indicators for the pollution level of the environment of the region, the levels of heavy metals along the coastal area of the province of Thai Binh in Vietnam were assessed, being compared with the results of other studies and regulation standards worldwide. After that, the baseline levels of heavy metals were established for this region, which can help future environment studies and decision-making by authorities. Furthermore, the results were evaluated using principal component analysis and linear regression analysis. The results identify possible accumulation of several heavy metals in the past, such as Se, Hg, Cu and Zn. Furthermore, several locations with particularly high levels of heavy metals were pointed out, particularly in terms of Se and Hg.
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