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Objective(s)

To compare the clinical pregnancy rates between intrauterine insemination (IUI) simultaneously or 34–36 h following hCG injection in gonadotropin-stimulated IUI cycles.

Study design

Randomized, prospective, controlled, study conducted in a university infertility clinic. Of 923 infertile couples, 220 couples with unexplained infertility or mild male factor infertility were included to the study. Before ovarian stimulation patients were randomized into two groups: IUI at 34–36 h after hCG injection (group I) (n = 106) and IUI simultaneously with hCG administration (group II) (n = 98). The primary outcome was clinical pregnancy rates.

Results

There was no significant difference between the groups according to baseline patient and cycle characteristics. Clinical pregnancy rates were 9.4% and 12.2% in group I and group II, respectively (p = 0.523). Although group II had better outcomes there was no statistically significant difference in clinical pregnancy rates between the different timing methods: IUI simultaneously with hCG versus IUI at 34–36 h after hCG (odds ratio (OR) = 1.35, 95% CI 0.53–3.42).

Conclusion(s)

There is no difference in simultaneous use of hCG injection compared to cycles in which IUI is performed after 34–36 h following hCG injection. Prospective randomized trials with larger sample sizes or meta-analyses are required.  相似文献   
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Neuromusculoskeletal (physical) frailty is an aging-attributable biomedical issue of extremely high import, from both public health and individual perspectives. Yet, it is rarely studied in nonhuman research subjects and very rarely studied in animals with extended longevity. In an effort to address this relatively neglected area, we have conducted a longitudinal investigation of the neuromusculoskeletal healthspan in mice with two senescence-slowing interventions: growth hormone (GH) resistance, produced by GH receptor “knockout” (GHR-KO), and caloric restriction (CR). We report marked improvements in the retention of strength, balance, and motor coordination by the longevity-conferring GHR/BP gene disruption, CR regimen, or a combination of the two. Specifically, GHR-KO mice exhibit superior grip strength, balance, and motor coordination at middle age, and CR mice display superior grip strength at middle age. The advantageous effects established by middle-age are more pronounced in old-age, and these robust alterations are, generally, not gender-specific. Thus, we show that genetic and/or dietary interventions that engender longevity are also beneficial for the retention of neuromusculoskeletal health and functionality. The translational knowledge to be gained from subsequent molecular or histological investigations of these models of preserved functionality and decelerated senescence is potentially relevant to the efforts to reduce the specter of fear, falls, fracture, and frailty in the elderly.  相似文献   
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Context: The fruit of Terminalia chebula Retz. (Combretaceae) has been used for several therapeutic purposes in Thai folk medicines. Currently, the ethanol extracts containing antioxidant compounds have shown the ability to promote collagen synthesis.

Objective: This purpose of this work was to study the effects of the ethanol extract from T. chebula fruit on the inhibition of cutaneous photodamage.

Materials and methods: The viability of human skin fibroblasts after incubation with T. chebula at concentration 0.5–50?μg/mL for 24, 48 and 72?h was assessed by using sodium 3′-[(phenyl-amino)-carbonyl]-3,4,tetrazolium-bis(4-methoxy-6-notro)benzene-sulphonic acid hydrate (XTT). The levels of type I procollagen and matrix metalloproteinases (MMP)-1 and MMP-13 produced by UVB-irradiated fibroblasts were determined by ELISA. Skin thickness and collagen content caused by long-term UVB irradiation in male ICR mice were determined from haematoxylin and eosin stained tissue sections and spectrophotometric measurement of hydroxyproline.

Results: The extract (0.5–50?μg/mL) had no effect on cell viability or morphology of the human fibroblasts. In vitro studies showed that the T. chebula extract reduced the UVB-induced MMP-1 and MMP-13 expression, whereas an increased production of type I procollagen was observed. In a UVB-irradiated animal model, male ICR mice with hair shaved were chronically exposed to UVB which lead to epidermal thickness and loss of hydroxyproline. However, these effects were fully prevented by the topical application of the T. chebula ethanol extract.

Discussion and conclusion: These data suggested that the T. chebula ethanol fruit extract is an efficacious pharmaceutical protectant of skin against photodamage.  相似文献   
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Cell cycle regulation and the NF-κB pathway in cancer cells are important in mediating resistance to 5-Fluorouracil (5-FU). Pentagamavunon-1 (PGV-1), a curcumin analog, is known to exhibit stronger growth inhibitory effects than curcumin itself in several cancer cells. In this study, we evaluated the potency of PGV-1 in combination with 5-FU in WiDr colon cancer cells. In MTT assays, PGV-1 did not only exhibit stronger growth inhibitory effects than both 5-FU and curcumin, but also enhanced the cytotoxicity of 5-FU. Flow cytometry demonstrated that single treatments with PGV-1 and 5-FU resulted in different effects on cell cycle profiles. PGV-1 induced G2/M arrest while 5-FU caused S-phase arrest at low concentration (1 μM) and G1-phase arrest at high concentration (100 μM). Interestingly, the combination of 5-FU and PGV-1 enhanced cell accumulation in S-phase. Although a single treatment with either 5-FU or PGV-1 increased cyclin D1 at the protein level, the combination treatment resulted in significant suppression. In addition, PGV-1 inhibited activation of NF-κB and suppressed the expression of cyclooxygenase-2, an NF-κB downstream protein. In conclusion, PGV-1 increased the cytotoxic effect of 5-FU on WiDr cells through inhibition of NF-κB activation.  相似文献   
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