Effect of storage duration, storage temperature, and diluent on the viability and fertility of fresh ram sperm

Cervical artificial insemination (AI) in sheep with fresh semen yields a much higher pregnancy rate than when frozen-thawed semen is used, and consequently frozen semen is only acceptable for laparoscopic insemination. The short life span of fresh semen is a major constraint on the use of AI in genetic improvement programs for sheep. The main objective of this study was to examine the effects of storage conditions on viability and fertilization ability of fresh ram (Ovis aries) semen up to 72 h postcollection. Experiment 1 was designed to evaluate the effect of diluent type (standard skim milk, AndroMed, OviPro, and INRA 96) and storage temperature (5 °C and 15 °C) on the motility and viability of fresh ram semen. Storage temperature, irrespective of diluent, had a significant effect on both motility and viability. Storage at 5 °C maintained acceptable motility and viability up to 72 h compared with that of storage at 15 °C. In Experiment 2, the penetrating ability of fresh ram semen, diluted in either skim milk, AndroMed, or INRA 96, was assessed using artificial mucus. Flat capillary tubes containing artificial mucus were suspended in 250 μL semen at a sperm concentration of 20 × 10⁶/mL. Semen was stored at 5 °C and tested after 6, 24, 48, and 72 h. There was a significant diluent by time interaction. In Experiment 3, the fertilizing ability of fresh ram semen stored at 5 °C was evaluated in vitro. Fresh semen (diluted in either skim milk, AndroMed, or INRA 96) was added to matured ewe oocytes at 6, 24, or 72 h after semen collection. Cleavage rate was recorded at 48 h postinsemination, and blastocyst development was recorded on Days 6 to 9. There was a significant treatment effect on cleavage and blastocyst rates; insemination of semen stored for 24 h resulted in higher rates than those for storage at 72 h. In Experiment 4, the fertilizing ability of fresh ram semen was evaluated in vivo. Semen was diluted in INRA 96, stored at 5 °C, and used to inseminate ewes on the day of collection or at 24, 48, and 72 h postcollection. Multiparous ewes were cervically inseminated at a synchronized estrus. Fertility rate decreased linearly (P < 0.001) up to 72 h after semen collection.     

Investigation of the Booroola (FecB) and Inverdale (FecX(I)) mutations in 21 prolific breeds and strains of sheep sampled in 13 countries

Twenty-one of the world's prolific sheep breeds and strains were tested for the presence of the FecB mutation of BMPR1B and the FecX(I) mutation of BMP15. The breeds studied were Romanov (2 strains), Finn (2 strains), East Friesian, Teeswater, Blueface Leicester, Hu, Han, D'Man, Chios, Mountain Sheep (three breeds), German Whiteheaded Mutton, Lleyn, Loa, Galician, Barbados Blackbelly (pure and crossbred) and St. Croix. The FecB mutation was found in two breeds, Hu and Han from China, but not in any of the other breeds. The 12 Hu sheep sampled were all homozygous carriers of FecB (FecB(B)/FecB(B)) whereas the sample of 12 Han sheep included all three genotypes (FecB(B)/FecB(B), FecB(B)/FecB+, FecB+/FecB+) at frequencies of 0.33, 0.58 and 0.08, respectively. There was no evidence of FecX(I) in any of the breeds sampled.     

High Uptake of Systematic HIV Counseling and Testing and TB Symptom Screening at a Primary Care Clinic in South Africa

Background

Timely diagnosis and treatment of tuberculosis (TB) and HIV is important to reduce morbidity and mortality, and break the cycle of ongoing transmission.

Methods

We performed an implementation research study to develop a model for systematic TB symptom screening and HIV counseling and testing (HCT) for all adult clients at a primary care clinic and prospectively evaluate the 6-month coverage and yield, and 18-month sustainability at a primary care clinic in Johannesburg, South Africa.

Results

During the first 6 months, 26,515 visits occurred among 12,078 adults. The proportion of adults aware of their HIV status was 43.7% at the start of the first visit, increased to 84.6% at the end of the first visit, and to 90% at end of any visit during the first 6 months. During these 6 months, 1042 clients were newly diagnosed with HIV. HIV prevalence was 22.9% among those newly tested, and 58.9% among all adult clinic clients. High coverage of systematic HCT was sustained across all 18 months. Coverage of systematic HIV-stratified TB symptom screening during first 6-months was also high (89.6%) but only 35.0% of those symptomatic were screened by sputum. During these 6-months, 90 clients had a positive Xpert MTB/RIF assay, corresponding to a TB prevalence of 0.4% among all 23,534 clients TB symptom-screened and 2.8% among the 3,284 clients with a positive TB symptom screen. The initial high coverage of TB symptom screening was not sustained, with coverage of TB symptom screening dropping after the first six months to 70% and assessment by sputum dropping to 15%.

Conclusion

Routine, systematic HCT and HIV-stratified TB symptom screening is feasible at primary care level. Systematic HCT doubled the proportion of clients with known HIV status. While HCT was sustainable, coverage of systematic TB screening dropped significantly after the first 6 months of implementation.     

Semisynthetic preparation of amentoflavone: A negative modulator at GABA(A) receptors

Amentoflavone is found in a number of plants with medicinal properties, including Ginkgo biloba and Hypericum perforatum (St. John's Wort). We have developed a rapid and economic semi-synthetic preparation of amentoflavone from biflavones isolated from autumnal Ginkgo biloba leaves. Several studies have shown that amentoflavone binds to benzodiazepine receptors. Using two electrode voltage-clamp methodology, amentoflavone has been shown to be a negative modulator of GABA at GABA(A) alpha(1)beta(2)gamma(2L) receptors expressed in Xenopus laevis oocytes This action appears to be independent of the flumazenil-sensitive benzodiazepine modulatory sites on the GABA(A) receptor.     

Substituted azaquinazolinones as modulators of GHSr-1a for the treatment of type II diabetes and obesity

Substituted azaquinazolinones were identified as antagonists of the GHSr-1A receptor for the treatment of type II diabetes and obesity. Optimisation for potency and LogD lead to the identification of orally bioavailable, potent antagonists with improved selectivity over hERG.     

Proinflammatory cytokine secretion is suppressed by TMEM16A or CFTR channel activity in human cystic fibrosis bronchial epithelia

Cystic fibrosis (CF) is caused by the functional expression defect of the CF transmembrane conductance regulator (CFTR) chloride channel at the apical plasma membrane. Impaired bacterial clearance and hyperactive innate immune response are hallmarks of the CF lung disease, yet the existence of and mechanism accounting for the innate immune defect that occurs before infection remain controversial. Inducible expression of either CFTR or the calcium-activated chloride channel TMEM16A attenuated the proinflammatory cytokines interleukin-6 (IL-6), IL-8, and CXCL1/2 in two human respiratory epithelial models under air–liquid but not liquid–liquid interface culture. Expression of wild-type but not the inactive G551D-CFTR indicates that secretion of the chemoattractant IL-8 is inversely proportional to CFTR channel activity in cftr^{∆F508/∆F508} immortalized and primary human bronchial epithelia. Similarly, direct but not P2Y receptor–mediated activation of TMEM16A attenuates IL-8 secretion in respiratory epithelia. Thus augmented proinflammatory cytokine secretion caused by defective anion transport at the apical membrane may contribute to the excessive and persistent lung inflammation in CF and perhaps in other respiratory diseases associated with documented down-regulation of CFTR (e.g., chronic obstructive pulmonary disease). Direct pharmacological activation of TMEM16A offers a potential therapeutic strategy to reduce the inflammation of CF airway epithelia.     

Electrogenic, K+-dependent chloride transport in locust hindgut

Potassium chloride is the major salt recycled in most insect secretory systems. Ion and water reabsorption occur in the rectum by active transport of Cl- and largely passive movement of K+. Both these processes are stimulated several fold by a neuropeptide hormone acting via cyclic AMP (cAMP). This Cl- transport process was investigated by using intracellular ion-sensitive microelectrodes, radiotracer flux measurements, voltage clamping, ion substitutions and inhibitors. the mucosal entry step for Cl- is energy-requiring and highly-selective, and is stimulated directly by cAMP and luminal K+. Under some experimental conditions, measured electrochemical potentials for cations across the mucosal membrane are too small to drive C;- entry by NaCl or KCl cotransport mechanisms; moreover, net 36Cl- flux is independent of the apical Na+ potential. Similarly no evidence for a HCO3- -Cl- exchange was obtained. We conclude that Cl- transport in locust gut is different from mechanisms currently proposed for vertebrate tissues.     

The Flavonoid Glycosides, Myricitrin, Gossypin and Naringin Exert Anxiolytic Action in Mice

The consumption of flavonoid-rich foods, in particular fruits and vegetables, has been epidemiologically associated with a reduced risk of heart disease, neurodegenerative disease, cancer and other chronic diseases. Flavonoid glycosides, the main class of flavonoids, have been shown to exert CNS-mediated activities, particularly as sedative-hypnotics, analgesics or both, nevertheless no studies have evaluated these agents in anxiety. This study assessed the potential anxiolytic effect of three flavonoid glycosides, myrcitrin, naringin and gossypin, in the elevated plus maze test (EPM). Myricitrin (1 mg/kg) was effective on the EPM showing a clear anxiolytic effect with no signs of sedation. However, higher doses showed possible sedative and myorelaxation effects. Gossypin and naringin both shared a similar profile, with low doses (1 mg/kg) inducing a robust anxiolytic effect which diminished with increasing doses of the flavonoids. Higher doses of these two flavonoids showed a dramatic increase in the open arm exploration accompanied by a decrease in locomotor activity. Hence, naringin (30 mg/kg) and gossypin (30 mg/kg) induce both anxiolytic and sedative effects. These results suggest that flavonoid glycosides have the potential to exert a range of CNS-mediated biological activities.