Measurement protocols and determinants of peak oxygen consumption in adults with Down syndrome: a systematic review.

This systematic review aimed to provide an overview of test protocols used to measure peak oxygen uptake (VO2peak) in adults with Down syndrome (DS) and to determine how generalisable the outcomes are for the entire population of adults with DS by describing the sample characteristics of these studies and their impact on VO2peak. A literature search (PROSPERO CRD42022309560) was performed (18 July 2023) using the following databases: PubMed, CINAHL, APA PsycINFO, Web of Science, Embase and SPORTDiscus. For articles to be included, they had to be peer-reviewed pubications, reporting VO2peak or VO2max for individuals with DS separately, with a sample of n ≥ 5 and a mean age ≥18 years. Systematic reviews and meta-analyses were excluded but their reference lists were searched for additional papers to include. Studies were evaluated for risk of bias following the guidelines of Kmet et al. The results were summarised with frequency statistics. Forty-three studies were included in this systematic review. Sample sizes of included adults with DS ranged from n = 4-226, with a total of n = 1498 adults with DS being included. Most studies (29/43) used the same standardised maximal exercise treadmill protocol to measure VO2peak in adults with DS, and 33 out of 43 studies used at least one objective criterion to determine a valid maximal effort. Participants were predominantly male, under 40 years old, and overweight or obese. Additionally, the diversity of study samples was lacking or not reported. The most widely used, standardised, maximal exercise test treadmill protocol is recommended for future use in research and practice, including objective criteria to determine valid maximal effort. The current study samples are not representative of the population of adults with DS in terms of sex, age and diverse backgrounds and therefore likely overestimate VO2peak of this population.

Feasibility of extracts of common Philippine succulents as ultrasound acoustic gel alternatives

@#<p style="text-align: justify;"><strong>Background.</strong> Ultrasound remains to be an ideal imaging tool for the diagnosis of various conditions in the body. However, the cost and unavailability of the commercial acoustic gel continue to hamper the tool's diagnostic value in low-resource communities.</p><p style="text-align: justify;"><strong>Objectives.</strong> The study aims to investigate the feasibility of extracts of common Philippine succulents as ultrasound acoustic gel, based on image quality parameters, organoleptic characteristics, spreadability, pH, and viscosity.</p><p style="text-align: justify;"><strong>Methods.</strong> Aloe Vera, common houseleek, burro's tail, snake plant, echeveria, crown of thorns, panda plant, and jade plant were extracted and filtered before subjecting them for a physical evaluation. The evaluation analyzed the organoleptic characteristics, spreadability, pH, and viscosity of the formulated gels. The commercial acoustic gel was used as the reference gel. Three experienced ultrasonographers blindly evaluated a total of 243 images obtained using the formulated gels based on four image quality parameters.</p><p style="text-align: justify;"><strong>Results.</strong> The formulated gels had optimal appearance, texture, homogeneity, and pH value. However, all of the extracts had a lower viscosity than the commercial reference gel. The extract obtained from the burro's tail exhibited the highest viscosity among the tested extracts. There was no significant difference in the image quality parameters among the commercial and formulated gels.</p><p style="text-align: justify;"><strong>Conclusion.</strong> The extracts obtained from the succulents are feasible as an acoustic gel for ultrasound imaging based on the physical and image quality analyses. The tested plants are readily available and easy to produce compared to commercial acoustic gel.</p>

Comparison of antimicrobial substantivity of root canal irrigants in instrumented root canals up to 72 h: an in vitro study.

Disinfection of the root canal system is one of the primary aims of root canal treatment. This can be achieved through the use of various antimicrobial agents in the form of irrigants and medicaments. The antimicrobial substantivity of 2% chlorhexidine gluconate, 1% povidone iodine, 2.5% hydrogen peroxide followed by 2% sodium hypochlorite, and 2% sodium hypochlorite alone as irrigants was assessed in instrumented root canals. 2% chlorhexidine showed antimicrobial substantivity lasting up to 72 h, followed by 1% povidone iodine, and 2% sodium hypochlorite. Thus 2% chlorhexidine should be used as a final rinse irrigant in endodontic treatment protocols.

Long-latency spinal reflexes in humans.

Stretching human muscles with a mechanical device gave rise to multiple peaks in the rectified and averaged electromyogram. In the first dorsal interosseous the latency of the first peak (M1) was 32.4 +/- 2.4 ms (SD) and the latency of the second peak (M2) was 55.1 +/- 11.3 ms, in both cases measured from the time of the stimulus to the take-off point of the peak. Often a third peak (M3) was seen, having a considerably longer latency. The origin of peak M1 was considered to be in the stretch reflex arc because of its latency and its invariable association with muscle movement. Peak M2 was due to stimulation of afferent terminals in the skin and/or subcutaneous tissues by the mechanical device producing the muscle stretch. The conduction velocity of the pathway involved in the generation of the M1 component is the same as that for M2. This implies that central processing in the spinal cord delays the M2 response. The M2 mechanism does not involve a transcortical (long-loop) pathway because in foot muscles the M1-M2 delay remains the same as is found for hand muscles, although M1 latency is prolonged (to 39.4 +/- 6.2 ms for extensor digitorum longus). This indicates that there is not time for M2 impulses to traverse a pathway any longer than that passing to and from the spinal cord.

Neuropathy in tetanus.

Thirty-four cases of severe tetanus were studied. On clinical examination weakness and sensory loss compatible with peripheral neuropathy was found in 27. The pattern was usually asymmetrical, the commonest nerves affected being ulnar, median and lateral popliteal, although occasionally circumflex, musculocutaneous, femoral and facial nerves were also involved. Electrophysiological studies showed spontaneous activity resembling denervation potentials, diphasic and positive sharp waves. In some muscles there was also activity resembling spontaneous firing of motor units. Motor and sensory conduction velocities in the affected nerves were moderately reduced and the amplitude of sensory potentials was also reduced. No conduction was found in 11 nerves in 8 patients on initial studies, but 4 out of 7 nerves that could be studied showed rapid recovery. Although most of the nerves in the rest of the patients showed clinical recovery, conduction velocities showed improvement most often when examined about 10 weeks after the onset of trismus. The clinical and electrophysiological evidence suggests the involvement of peripheral nerves in severe tetanus. Serum neuritis, hypersensitivity reaction to tetanus toxoid or drug-induced neuropathy have been ruled out.

Cephalic tetanus: demonstration of a dual lesion.

A clinical and electrophysiological study of 15 cases of cephalic tetanus is reported. This condition is a form of local tetanus which commonly follows an injury to the face or head. It is characterised by muscle paralysis which is maximal close to the site of injury, while spasm is evident at mroe distant sites. As muscle paralysis improves with time it is succeeded by spasm. It is argued that paralysis is due to high local concentrations of toxin in the brainstem while lesser concentrations cause spasm by abolishing inhibition. Electrophysiological studies indicate that paralysis is of lower motor neurone type with denervation potentials, hyperirritability, loss of motor units, and marginally increased distal latencies being the features recorded.