Dynamics of childhood obesity in Hong Kong throughout the COVID-19 pandemic before and after the school closures: a 3-year longitudinal study.

OBJECTIVE: This study is to evaluate if there is any difference in the balance between incidence of and remission from overweight/obesity in Hong Kong school-age children before and during the COVID-19 pandemic over three years. METHODS: This is a retrospective longitudinal study that involved children aged 6-16 years from a database of the School Physical Fitness Award Scheme. RESULTS: 2765 students were longitudinally followed up for two years. The prevalence of childhood overweight/obesity was increased between the 2019 and 2021 academic years (P < 0.001). During the COVID-19 pandemic, the rate of obesity remission significantly reduced by 7.9 % (P = 0.003), at a background of a plateau of obesity among children and adolescents. CONCLUSIONS: Our study provides evidence on the impact of school closure and home confinement as a standard infection control measure for the prevention of COVID-19, which are likely to break the balance between incidence of and remission from childhood obesity.

The Griffiths Development Scales-Chinese (GDS-C): A cross-cultural comparison of developmental trajectories between Chinese and British children.

BACKGROUND: The Griffiths Mental Development Scales (GMDS) are used in many countries to assess the development of children from birth to 8 years. There is a need for accurate and culturally appropriate developmental assessment tools for Chinese children. Here, we adapted the GMDS for use in Chinese children and compare the developmental trajectories between Chinese and British children. METHODS: Children with typical development were recruited from 7 urban cities in China between 2009 and 2013. The Griffiths Mental Development Scales-Chinese (GDS-C) were adapted and used to assess the development of urban Chinese children. Developmental curves were computed for 6 subscales using learning management system methods and compare against the British curves from the Griffiths Mental Development Scales-Extended Revised (GMDS-ER). RESULTS: The GDS-C were used to assess the developmental status of 815 Chinese children. Plots of the 1st, 5th, 10th, 25th, 50th, 75th, 90th, 95th, and 99th percentiles, and full percentile tables were obtained, which showed similar trends to data from the British GMDS-ER. CONCLUSIONS: The Chinese developmental curves obtained from the GDS-C showed similarities and differences to the developmental curves from the British GMDS-ER. The development of urban Chinese children should be assessed with the culturally appropriate GDS-C.

Purification and characterization of alpha- and beta-benincasins, arginine/glutamate-rich peptides with translation-inhibiting activity from wax gourd seeds.

Two peptides, with a molecular mass of about 11 kDa and an N-terminal sequence abundant in arginine and glutamine residues, were isolated from wax gourd seeds. The isolation protocol included affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on Mono-S and gel filtration on Superdex 75. The peptides, designated alpha- and beta-benincasins, inhibited cell-free translation in a rabbit reticulocyte lysate system with an IC(50) of 20 and 320 pM, respectively. Alpha-benincasin exhibited weak antifungal activity toward Coprinus comatus and Physalospora piricola but not toward Mycosphaerella arachidicola.

Purification and characterization of moschins, arginine-glutamate-rich proteins with translation-inhibiting activity from brown pumpkin (Cucurbita moschata) seeds.

From fresh brown pumpkin seeds, two proteins with a molecular mass of 12kDa and an N-terminal sequence rich in arginine and glutamate residues were obtained. The protein designated alpha-moschin closely resembled the fruitfly programmed-cell death gene product and the protein designated beta-moschin demonstrated striking similarity to prepro 2S albumin in N-terminal sequence. alpha- and beta-moschins inhibited translation in the rabbit reticulocyte lysate system with an IC(50) of 17 microM and 300nM, respectively.

Isolation and characterization of luffacylin, a ribosome inactivating peptide with anti-fungal activity from sponge gourd (Luffa cylindrica) seeds.

A purification scheme involving ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, and ion exchange chromatography on CM-Sepharose and Mono S was employed to isolate a peptide with a molecular weight of 7.8kDa from sponge gourd seeds. The peptide, which was designated luffacylin, exhibited an N-terminal sequence with pronounced resemblance to that of the 6.5kDa arginine-glutamate rich polypeptide previously isolated from sponge gourd seeds. Luffacylin inhibited translation in a rabbit reticulocyte lysate system with an IC(50) of 140pM and reacted positively in the N-glycosidase assay for ribosome inactivating proteins. Luffacylin exerted anti-fungal activity against Mycosphaerella arachidicola and Fusarium oxysporum.

Purification and characterization of charantin, a napin-like ribosome-inactivating peptide from bitter gourd (Momordica charantia) seeds.

A peptide designated charantin, with a molecular mass of 9.7 kDa, was isolated from bitter gourd seeds. The procedure comprised affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on Mono S and gel filtration on Superdex 75. The N-terminal sequence of charantin exhibited marked similarity to that of the 7.8-kDa napin-like peptide previously isolated from bitter gourd seeds. Charantin inhibited cell-free translation in a rabbit reticulocyte lysate system with an IC50 of 400 nm, a potency lower than that of the previously reported small ribosome-inactivating protein gamma-momorcharin (IC50 = 55 nm) which also exhibited an abundance of arginine and glutamate/glutamine residues. Charantin reacted positively in the N-glycosidase assay, yielding a band similar to that formed by the small ribosome-inactivating proteins gamma-momorcharin and luffin S.

The structural specificity of carbohydrate in the initiation of rat sperm motility.

Mammalian spermatozoa are stored in the cauda epididymis (CE) in a quiescent state and become motile when diluted with seminal plasma upon ejaculation. The structural specificity of a variety of sugars and sugar derivatives as diluents that are capable of initiating a transition of CE spermatozoa from the quiescent to the actively motile state was examined. It was found that monosaccharides, except those containing less than five-carbon skeletons, were good motility initiators; a trisaccharide tested showed reduced activity. The initiation activity was also independent of the structural stereospecificity and the nutritional value of the sugar. Based on these observations, a mechanism involving a receptor which handles sugar transport or sugar recognition in a transport process is proposed to be responsible for generating a signal that triggers CE spermatozoal motility.

Gossypol inhibits Ehrlich ascites tumor cell proliferation.

Neutral gossypol solution injected peritoneally into NMRI mice preimplanted with Ehrlich ascites tumour cell, at a dose of 25-100 micrograms/mouse per day, lengthened the number of survival days of the hosts. This gossypol effect on tumour cell proliferation is concentration dependent. The optimum dose is 100 micrograms. However, at too high a dose, the gossypol caused a body weight loss and the death of the tumour-bearing mice.

Effect of gossypol on boar spermatozoal adenosine triphosphate metabolism.

The effect of gossypol on boar spermatozoal adenosine triphosphate (ATP) metabolism was investigated. Gossypol has little effect on the activities of the total spermatozoal ATPase, the spermatozoal flagellar ATPase, and the mitochondrial fragment ATPase. The membrane ATPase, being exceedingly low, has not been considered for its susceptibility toward gossypol. Gossypol uncouples spermatozoal oxidative phosphorylation. A biphasic response (stimulation at low concentration and inhibition at high concentration) has been noticed in anaerobic lactate production and hypotonically treated spermatozoal mitochondrial ATPase activity. The ATP content, either under aerobic or anaerobic condition was reduced by gossypol with the reduction threshold of ATP more sensitive in the latter. The reduction of ATP follows two different reaction kinetics in which it is stabilized at moderate gossypol concentrations but progresses along with time at high concentrations. Since the drop in motility is more sensitive than the drop in ATP content and since the flagellar ATPase is not significantly inhibited by gossypol, a motility controlling component that is more sensitive to gossypol antimotility inhibition is proposed.

[Cottonseed--a source of vaginal contraceptive (author's transl)]. / La graine de coton a l'origine d'une contraception vaginale.

PIP: The antifertility effect of the cottonseed oil, gossypol, had been first observed in China, where it was administered orally to over 40,000 healthy males, with an effectiveness of 99%. The authors of this study have tried gossypol as a vaginal contraceptive. Gossypol acetic acid was dissolved in 0.5 N NaOH, and then diluted. The solution obtained was added to a similar volume of seminal liquid, and sperm motility was carefully measured. The immobilization of spermatozoa was total. The same results were obtained with seminal liquid from rats. One added advantage of vaginal administration of gossypol would be its lubricating quality.^ieng

Gossypol uncoupling of respiratory chain and oxidative phosphorylation in ejaculated boar spermatozoa.

Gossypol, a promising male contraceptive isolated from cottonseed oil, inhibits spermatozoal motility. This antimotility effect accompanies a biphasic change in the spermatozoal respiratory rate: a stimulation at low concentrations and an inhibition at high concentrations. With various respiratory inhibitors, gossypol was shown to take effect by the uncoupling of the respiratory chain and the oxidative phosphorylation. The implication of this uncoupling action in the strategy of producing an ideal gossypol-like male contraceptive is discussed.

Cottonseed oil as a vaginal contraceptive.

The effect of gossypol acetic acid an cottonseed oil emulsion on human spermatozoal motility was tested. Contrary to a recent report [Waller et al. (1980): Contraception 22:183-187] that gossypol acetic acid is harmless to human spermatozoal motility in vitro, 10-3 M gossypol acetic acid completely abolished spermatozoal motility. This discrepancy might have stemmed from an oversight in the gossypol solubility. Cottonseed oil emulsion also exhibited spermatozoal motility inhibition. The applicability of this natural low toxicity cottonseed oil as vaginal contraceptive was explored

PIP: Gossypol has been shown to be an effective oral male contraceptive. This paper examines the effect of gossypol acetic acid and cottonseed oil buffer emulsion on human spermatozoal motility. Gossypol solution was prepared as described. Equal volumes of human semen and test solutions were mixed thoroughly for spermatozoal motility microscopic examination. A photographic tracking method described in an earlier paper was used to measure progressive spermatozoal motility. A slight but reproducible stimulation in spermatozoal activity was observed at low gossypol acetic acid concentrations (10-5M). Increased motility was observed throughout the experiment. At 10-3M gossypol concentration, complete abolition of spermatozoal motility occurred; at this concentration, the preparation contained minute crystals of gossypol acetic acid. Similar results were seen with rat epididymis spermatozoa. Spermatozoal progressive motility was completely abolished by cottonseed oil, either as saturated emulsion or 5 times diluted, and independent of whether or not solid kernel particles were present in the emulsion. An effective uncoupler of oxidative phosphorylation, gossypol reduces spermatozoal adenosine triphosphate content and thus reduces motility as observed in boar, human, and rat spermatozoa. As a 5-fold diluted sample of cottonseed oil showed significant spermatozoal antimotility activity, and cottonseed oil has little side effects and is economical to use, use of this natural oil as a contraceptive for vaginal application should be investigated.

Variations of gossypol susceptibility in rat spermatozoa during spermatogenesis.

Sperm collected at two epididymal regions from various rat groups force-fed with gossypol were assayed for their ATP levels and motilities to examine their response to the antifertility effect of gossypol, a yellowish polyphenolic pigment from cottonseed oil. Rats receiving gossypol administration for 2 weeks began to show a proportional decrease in spermatozoal ATP content and motility and this antifertility effect deepened with time. Recovery from the gossypol-induced ATP decrease also developed at 2 weeks after the removal of gossypol administration. This rapid development of both the inhibitory and the recovery effects in a normal 53-day spermatogenic process might have stemmed from a change of susceptibility to gossypol inhibition during spermatogenesis. A model showing a more susceptible middle stage in spermatogenesis is proposed.