Effects of insulin-like growth factor-1 on the mRNA expression of estradiol receptors, steroidogenic enzymes, and steroid production in bovine follicles

Insulin-like growth factor-1 (IGF-1) plays a crucial role in follicular growth and stimulates steroid hormone production in bovine follicles. Steroid hormones are synthesized through the actions of steroidogenic enzymes, specifically STAR, CYP11A1, HSD3B, and CYP19A1 in both theca cells (TCs) and granulosa cells (GCs), under the influence of gonadotropins. Particularly, estradiol 17β (E2) assumes a central role in follicular development and selection by activating estrogen receptors β (ESR2) in GCs. We assessed ESR2 mRNA expression in GCs of developing follicles and investigated the impact of IGF-1 on the mRNA expression of ESR2, CYP19A1, FSHR, and LHCGR, STAR, CYP11A1, and HSD17B in cultured GCs and TCs, respectively. Additionally, we assessed the influence of IGF-1 on androstenedione (A4), progesterone (P4), and testosterone (T) production in TCs. Small-sized follicles (< 6 mm) exhibited the highest levels of ESR2 mRNA expression, whereas medium-sized follicles (7-8 mm) displayed higher levels than large-sized follicles (≥ 9 mm) (P < 0.05). IGF-1 increased the mRNA expression of ESR2, CYP19A1, and FSHR in GCs of follicles of both sizes, except for FSHR mRNA in medium-sized follicles (P < 0.05). IGF-1 significantly elevated mRNA expression of LHCGR, STAR, CYP11A1, and CYP17B in TCs of small- and medium-sized follicles (P < 0.05). Moreover, IGF-1 augmented the production of A4 and P4 but had no impact on T production in TCs of small- and medium-sized follicles. Taken together, our findings indicate that IGF-1 upregulates steroidogenic enzymes and steroid hormone production, underscoring the crucial role of IGF-1 in follicle development and selection.

Inequities in the deployment of COVID-19 vaccine in the WHO Eastern Mediterranean Region, 2020-2021

The WHO Eastern Mediterranean Region (EMR) is characterised by a large range in routine immunisation coverage. We reviewed progress in access, deployment efforts, and use of COVID-19 vaccines in the EMR to identify bottlenecks and propose recommendations. We compiled and analysed data reported to WHO regarding the number of vaccines provided emergency use authorisation (EUA) in each country, the number of vaccine doses allocated and delivered by COVAX, the number of vaccine doses received bilaterally, the date of initiation of vaccination, vaccine usage rate and overall vaccination coverage. In June-July and October-November 2021, we conducted two rounds of a regional survey to assess vaccine acceptance and calculated the weighted proportion of individuals who would get vaccinated once a vaccine is available and recommended. We stratified the analysis according to four groups based on their participation status in COVAX, from the highest to lowest income, that is, (1) fully self-financing high-income countries (group 1), (2) fully self-financing upper middle-income countries (group 2), (3) Advance Market Commitment (AMC) countries not eligible to receive Gavi support (group 3) and (4) AMC countries eligible for Gavi support (group 4). As of 31 December 2021, the median number of vaccines provided with EUA was 6 for group 1, 11 for group 2, 8 for group 3 and 9 for group 4. On the same date, COVAX had delivered 179 793 310 doses to EMR countries. Vaccination started on 10 December 2020 in group 1, on 13 December 2020 in group 2, on 30 December 2020 in group 3 and on 20 January 2021 in group 4. The regional acceptance survey (first round) pointed to higher vaccine acceptance in group 1 (96%), than in others, including group 2 (73.9%), group 3 (78.8%) and group 4 (79.3%), with identical patterns in the second round (98%, 78%, 84% and 76%), respectively. Usage of vaccine allocated by COVAX to participating countries was 89% in group 1, 75% in group 2, 78% in group 3 and 42% in group 4. The full dose and partial dose coverage decreased with the income groups of countries, from 70% and 6% in group 1, to 43% and 8% in group 2, to 33% and 11% in group 3, and 20% and 8% in group 4. All 22 EMR countries introduced COVID-19 vaccines by 21 April 2021, but with major inequities in coverage. Additional efforts are needed to address the determinants of unequal vaccine coverage at all stages of the result chain to improve vaccine equity.

[Blood-transmitted viral infections among haemophiliacs in Tunisia]

In this work, we proposed to evaluate prevalences of hepatitis B and C viruses and Parvovirus B19 among 70 Tunisian haemophiliacs treated with clotting factors imported from Europe and/or locally produced cryoprecipitate; among them 6 (8.6%) are known HIV positive patients. HBs antigen, anti-HBc antibodies and anti-Parvovirus B19 antibodies were detected in 7.1%, 52.9% and 91.8%, respectively. HCV prevalence, defined as positive ELISA with positive Immunoblot and/or PCR was 50.0%. Prevalences of these viral infections in haemophiliacs are higher than prevalences detected among general population and in the control group of the study. HCV infection is less frequent in haemophiliacs born after 1985, the year of introduction of the inactivation procedures in the production of coagulation factors concentrates; it decreases more considerably after 1994, date of introduction of systematic screening of HCV among blood donors. In contrast, despite the inactivation of the factors concentrates and the systematic screening of the blood donations against HBs antigen, since 1973, the risk of HBV infection contamination remains high in the Tunisian haemophiliacs. The introduction in 1995 of hepatitis B vaccination in the national schedule of new-born vaccination may resolve in the future the problem of HBV infection in haemophiliacs and in the other categories of the Tunisian population.

Augmentation of protein synthesis and degradation by poor dietary amino acid balance in European sea bass (Dicentrarchus labrax)

Sea bass fry were fed a fixed ration of one of six isonitrogenous diets differing in essential amino acid balance or physical and chemical state of the protein source (Hydrolysate vs. intact protein) to induce different growth rates. The reference diet was based on fish meal, whereas the other diets contained fish protein hydrolysate, greaves meal (i.e., defatted collagen meal) or hydrolyzed feather meal added at 30 or 50% of crude protein at the expense of fish meal protein. Digestibility as well as fractional rate of whole-body protein synthesis was assessed. Whole-body protein synthesis was determined for each group of fish using a single injection of flooding dose of tritiated phenylalanine. Protein digestibility of the diets varied only by 5.5%. Specific growth rate and fractional protein specific growth rate, i.e., fractional protein accretion, were higher in fish fed the reference diet than in those fed the diets in which 50% of fish meal protein had been replaced by greaves or hydrolyzed feather meal protein. Compared with the reference group, whole-body protein synthesis was higher in fish fed these latter diets as well as in those fed the diet containing 30% greaves meal protein. The fractional protein accretion to fractional protein synthesis ratio, i.e., the efficiency of protein deposition, was lower in fish fed poorer dietary amino acid balance than in the reference group. The substitution of fish protein hydrolysate for intact fish protein led to a similar, though less pronounced phenomenon: nonsignificant increase in protein synthesis accompanied by significant increase in protein degradation.(ABSTRACT TRUNCATED AT 250 WORDS)