Decorticated Momordica charantia seeds were extracted and processed by a method which was developed originally for the purification of insect and annelid insulins. Essentially, the method entailed HCl--ethanol extraction, neutralization with NH4OH, gel filtration on Sephadex G-50, ion exchange chromatography on CM Sepharose CL-6B and desalting on Sephadex G-10. Of the seven fractions collected, three fractions were obtained with antilipolytic and lipogenic activities in isolated adipocytes and one fraction with only lipogenic activity. The data indicate that molecules with insulin-like bioactivity are present in Momordica charantia seeds. 相似文献
The effect of the KCNQ channel blockers XE991, chromanol 293B and linopirdine, was studied on voltage-dependent K+ currents in smooth muscle cells dissociated freshly from mouse portal vein (mPV) and isometric tension recordings from whole mPV. Voltage clamp experiments showed XE991 inhibited an outward current in a concentration-dependent manner with an IC50 of 5.8 microM. Block was voltage independent. Chromanol 293B and linopirdine also blocked the voltage-dependent K+ current but were less potent than XE991. At least two components--a linear (I(linear)) and an outward relaxation (I(out))--contributed to the XE991-sensitive conductance. XE991-sensitive currents were sustained at all test potentials and XE991 inhibited the enhanced holding current at -60 mV produced by bathing cells in an external solution containing 36 mM KCl. Current clamp experiments in the perforated-patch configuration showed XE991 and linopirdine depolarised the resting membrane potential and augmented the evoked response in a concentration-dependent manner. In functional experiments the spontaneous contractile activity of the mPV was increased significantly by XE991 and linopirdine. The stimulatory effect of XE991 was not affected by the presence of 4-AP, glibenclamide nor paxilline. These data provide evidence for an important role for KCNQ channels in governing cellular excitability in mPV smooth muscle cells. 相似文献
OBJECTIVE: To evaluate expectation and knowledge on obstetric ultrasound examination in the first and second trimester in a Chinese population. METHOD: A cross-sectional survey was conducted in a university obstetric clinic in Hong Kong. Chinese pregnant women who underwent the first trimester early scan sessions, or the second trimester anomaly scan sessions were invited to complete a self-administered questionnaire, which contained items on their knowledge, expectation, and sociodemographic characteristics. RESULTS: In all 276 eligible pregnant women (117 in the first trimester and 159 in the second trimester) were recruited. Although 249 women (90.2%) claimed they understood the indication of the ultrasound examination, only 93 of them were correct (33.7%). The median perceived overall-detection rate for structural abnormalities was 66.5%. Living in Hong Kong for more than 7 years was significantly associated with higher knowledge level and expectation from ultrasound examination. Attaining tertiary education level was also significantly associated with higher knowledge level. Over 90% of the pregnant women studied wished to know the fetal gender from the anomaly scan examination. CONCLUSION: Knowledge of Chinese pregnant women on ultrasound was generally unsatisfactory. Understanding their limitation of knowledge and expectations helps to devise appropriate education in the local setting. 相似文献
Early secretory and endoplasmic reticulum (ER)-localized proteins that are terminally misfolded or misassembled are degraded by a ubiquitin- and proteasome-mediated process known as ER-associated degradation (ERAD). Protozoan pathogens, including the causative agents of malaria, toxoplasmosis, trypanosomiasis, and leishmaniasis, contain a minimal ERAD network relative to higher eukaryotic cells, and, because of this, we observe that the malaria parasite Plasmodium falciparum is highly sensitive to the inhibition of components of this protein quality control system. Inhibitors that specifically target a putative protease component of ERAD, signal peptide peptidase (SPP), have high selectivity and potency for P. falciparum. By using a variety of methodologies, we validate that SPP inhibitors target P. falciparum SPP in parasites, disrupt the protein’s ability to facilitate degradation of unstable proteins, and inhibit its proteolytic activity. These compounds also show low nanomolar activity against liver-stage malaria parasites and are also equipotent against a panel of pathogenic protozoan parasites. Collectively, these data suggest ER quality control as a vulnerability of protozoan parasites, and that SPP inhibition may represent a suitable transmission blocking antimalarial strategy and potential pan-protozoan drug target. 相似文献
Accumulating evidence suggests that presence of macrophages in the tumor microenvironment add to the invasive and tumor-promoting hallmarks of cancer cells by secreting angiogenic and growth factors. RKIP is a known metastasis suppressor and interferes with several steps of metastasis. However, the mechanistic underpinnings of its function as a broad metastasis suppressor remain poorly understood. Here, we establish a novel pathway for RKIP regulation of metastasis inhibition through the negative regulation of RANTES/CCL5 thereby limiting tumor macrophage infiltration and inhibition of angiogenesis. Using a combination of loss- and gain-of-function approaches, we show that RKIP hinders breast cancer cell invasion by inhibiting expression of the CC chemokine CCL5 in vitro. We also show that the expression levels of RKIP and CCL5 are inversely correlated among clinical human breast cancer samples. Using a mouse allograft breast cancer transplantation model, we highlight that ectopic expression of RKIP significantly decreases tumor vasculature, macrophage infiltration and lung metastases. Mechanistically, we demonstrate that the inhibition of the CCL5 expression is the cause of the observed effects resulting from RKIP expression. Taken together, our results underscore the significance of RKIP as important negative regulator of tumor microenvironment. 相似文献
Objectives: To compare indicators relating to aging and health among veterans and non-veterans, and identify factors associated with subjective wellbeing (SWB) of older New Zealand veterans.
Methods: Self-reported data were obtained from participants in a longitudinal cohort study of New Zealand older adults. Responses from 352 veterans and 1500 non-veterans (age range of 55–86 and gender matched) were selected as a comparison group on indicators related to health and aging. The association of these indicators with veterans’ SWB were assessed using hierarchical regression.
Results: Apart from being older, smoking more, and having more chronic conditions, veterans did not differ from non-veterans on indicators of health and wellbeing. Mental health, physical health, purpose in life, housing satisfaction, and capabilities (choice and freedom) accounted for a significant amount of variance in veterans’ SWB.
Conclusion: Our results suggest that older veterans do not differ greatly on indices of health and aging from their non-veteran peers. Results support previous findings that lower mental and physical health is associated with lower SWB for veterans. Building upon prior findings, the current results demonstrate that interventions focusing on enhancing a sense of purpose in life, supporting one's capability to achieve, and strengthening social and physical environment through social connectedness, may serve as protective factors for SWB in veterans. 相似文献