Effects of melatonin on testicular function in adult male mice under different photoperiods.

Photoperiod is an important environmental factor affecting animal physiological function. Melatonin is an endogenous hormone that plays an important role in circadian and seasonal (or cyclical) rhythms and seasonal reproduction in mammals. To investigate the effects of melatonin on the reproductive performance of adult male mice under different photoperiods, sixty mice were randomly allotted to six groups: control (Light Dark, 12 L:12 D), control plus melatonin (MLD, 12 L:12 D), 24-hour continuous light (LL, 24 L:0 D), 24-hour continuous light plus melatonin (MLL 24 L:0 D), constant darkness (DD, 0 L:24 D), and constant darkness plus melatonin (MDD, 0 L:24 D). Normal saline (100 µL) was injected into the LD, LL, and DD groups at noon each day; the MLD, MLL, and MDD groups were injected with melatonin (1 mg/mL; 2 mg/kg·body weigh). After 24 hours of prolonged light exposure, testis morphology decreased, convoluted seminiferous tubules became sparse, the diameter of convoluted seminiferous tubules decreased, and the level of sex hormones decreased. After the administration of exogenous melatonin, testicular morphology and sex hormone levels decreased in the MLD group under normal light conditions. In the MLL group, the testicular tissue morphology returned to normal, the diameter of convoluted tubules increased, the hormone levels of LH (Luteinizing hormone) and MTL (melatonin) significantly increased (P<0.05), and th0e gene expressions of LHß and Mtnr1A (Melatonin receptors 1A) increased. There was almost no difference in the MDD group under continuous darkness. In conclusion, melatonin can damage the reproductive performance of male mice under normal light conditions, while exogenous melatonin can alleviate and protect the testicular injury of male mice under continuous light conditions.

Dexmedetomidine Leads to the Mitigation of Myocardial Ischemia/Reperfusion-Induced Acute Lung Injury in Diabetic Rats Via Modulation of Hypoxia-Inducible Factor-1α

ABSTRACT Introduction: The objective of this study is to investigate the protective mechanism of dexmedetomidine (Dex) in myocardial ischemia/reperfusion (MIR)-induced acute lung injury (ALI) of diabetic rats by inhibiting hypoxia-inducible factor-1α (HIF-1α). Methods: Initially, healthy male Sprague Dawley rats were treated with streptozocin to induce diabetes. Then, three weeks after the induction, Dex or lentiviral vector (LV)-HIF-1α was injected into the rats 30 minutes prior to the MIR modeling. After four weeks, lung tissues were harvested for pathological changes observation and the wet/dry weight (W/D) ratio determination. Afterwards, oxidative stress indicators and pro-inflammatory factors were measured. In addition, HIF-1α expression was assessed by immunohistochemistry and western blot analysis. Results: Dex could suppress inflammatory cell infiltration, improve lung tissue structure, reduce pathological score and the W/D ratio, and block oxidative stress and inflammatory response in MIR-induced ALI of diabetic rats. Besides, Dex could also inhibit HIF-1α expression. Moreover, Dex + LV-HIF-1α reversed the protective role of Dex on diabetic MIR-induced ALI. Conclusion: Our study has made it clear that Dex inhibited the upregulation of HIF-1α in diabetic MIR-induced ALI, and thus protect lung functions by quenching the accumulation of oxygen radical and reducing lung inflammatory response.

Dexmedetomidine Leads to the Mitigation of Myocardial Ischemia/Reperfusion-Induced Acute Lung Injury in Diabetic Rats Via Modulation of Hypoxia-Inducible Factor-1α.

INTRODUCTION: The objective of this study is to investigate the protective mechanism of dexmedetomidine (Dex) in myocardial ischemia/reperfusion (MIR)-induced acute lung injury (ALI) of diabetic rats by inhibiting hypoxia-inducible factor-1α (HIF-1α). METHODS: Initially, healthy male Sprague Dawley rats were treated with streptozocin to induce diabetes. Then, three weeks after the induction, Dex or lentiviral vector (LV)-HIF-1α was injected into the rats 30 minutes prior to the MIR modeling. After four weeks, lung tissues were harvested for pathological changes observation and the wet/dry weight (W/D) ratio determination. Afterwards, oxidative stress indicators and pro-inflammatory factors were measured. In addition, HIF-1α expression was assessed by immunohistochemistry and western blot analysis. RESULTS: Dex could suppress inflammatory cell infiltration, improve lung tissue structure, reduce pathological score and the W/D ratio, and block oxidative stress and inflammatory response in MIR-induced ALI of diabetic rats. Besides, Dex could also inhibit HIF-1α expression. Moreover, Dex + LV-HIF-1α reversed the protective role of Dex on diabetic MIR-induced ALI. CONCLUSION: Our study has made it clear that Dex inhibited the upregulation of HIF-1α in diabetic MIR-induced ALI, and thus protect lung functions by quenching the accumulation of oxygen radical and reducing lung inflammatory response.

Effects of melatonin on testicular function in adult male mice under different photoperiods

Photoperiod is an important environmental factor affecting animal physiological function. Melatonin is an endogenous hormone that plays an important role in circadian and seasonal (or cyclical) rhythms and seasonal reproduction in mammals. To investigate the effects of melatonin on the reproductive performance of adult male mice under different photoperiods, sixty mice were randomly allotted to six groups: control (Light Dark, 12 L:12 D), control plus melatonin (MLD, 12 L:12 D), 24-hour continuous light (LL, 24 L:0 D), 24-hour continuous light plus melatonin (MLL 24 L:0 D), constant darkness (DD, 0 L:24 D), and constant darkness plus melatonin (MDD, 0 L:24 D). Normal saline (100 µL) was injected into the LD, LL, and DD groups at noon each day; the MLD, MLL, and MDD groups were injected with melatonin (1 mg/mL; 2 mg/kg·body weigh). After 24 hours of prolonged light exposure, testis morphology decreased, convoluted seminiferous tubules became sparse, the diameter of convoluted seminiferous tubules decreased, and the level of sex hormones decreased. After the administration of exogenous melatonin, testicular morphology and sex hormone levels decreased in the MLD group under normal light conditions. In the MLL group, the testicular tissue morphology returned to normal, the diameter of convoluted tubules increased, the hormone levels of LH (Luteinizing hormone) and MTL (melatonin) significantly increased (P<0.05), and th0e gene expressions of LHß and Mtnr1A (Melatonin receptors 1A) increased. There was almost no difference in the MDD group under continuous darkness. In conclusion, melatonin can damage the reproductive performance of male mice under normal light conditions, while exogenous melatonin can alleviate and protect the testicular injury of male mice under continuous light conditions.(AU)

Short Tandem Repeats in plants: genomic distribution and function prediction

BACKGROUND: Short Tandem repeats (STRs) existed as popular elements in both eukaryotic and prokaryotic genomes. RESULTS: In this study, we analyzed the characteristics, distributions, and motif features of STRs within whole-genomes of 140 plant species. The results showed that STR density was negatively correlated with the genome size. Hexanucleotide repeat was the most abundant type of STRs. The distribution of algae shows a preference different from that of other plants. By analyzing GC contents of STRs and genome, it was concluded that STR motif was influenced by GC contents. Analysis of the long STRs in genome (length 1000 bp) found that dicots have the more long STRs. For STR types, di- and tri-nucleotide accounted for the highest proportion. Analyzing and designing long STRs in CDS (length 500 bp) was to verify the role of long STRs in Gossypium hirsutum TM-1 and Solanum tuberosum. By comparing the long STRs found in Fragaria x ananassa with other species, some evolutionary characteristics of the long STRs were obtained. CONCLUSIONS: We got the characteristics, distribution, and motif features of STRs in the whole genome of 140 plants and obtained some evolutionary characteristics of long STRs. The study provides useful insights into STR preference, characteristics, and distribution in plants.

Abdomen agudo quirúrgico en embarazadas / Surgical acute abdomen during pregnancy

Se presenta una revisión de 52 casos de abdomen agudo no obstétricos durante el embarazado, ocurridos en los servicios de maternidad, urgencia y cirugía del Hospital Barros Luco Trudeau. La frecuencia fue de 1 por 2700 partos, siendo la causa más importante la apendicitis aguda (59,6 por ciento) con una frecuencia de 1 por 3500 partos, seguida por los quistes anexiales complicados (17,3 por ciento) y colecistitis aguda (7,7 por ciento). Ocurrió con más frecuencia en el tercer trimestre del embarazo (44,2 por ciento). El porcentaje total de pérdidas feto-neonatales fue de 22,2 por ciento, y 31,8 por ciento cuando se asoció a peritonitis apendicular. La mortalidad materna fue cero. El diagnóstico diferencial más frecuente con apendicitis aguda fue pielonefritis aguda (41,7 por ciento). Concluimos que la apendicitis aguda es la causa más frecuente de abdomen agudo durante el embarazo y el pronóstico perinatal está dado por el tiempo de evolución y los riesgos de perforación y peritonitis