Induction of glucose-regulated protein 78 in rat uterine glandular epithelium during uterine sensitization for the decidual cell reaction.
Endometrial receptivity for implantation and sensitization for decidualization in rodents is a transient state under the control of the ovarian steroids estrogen and progesterone. It is unclear, however, what molecular events mediate the onset of uterine receptivity. Messenger RNA differential display was performed on endometrial RNA from ovariectomized rats differentially sensitized for decidualization. Maximally sensitized uteri were at the equivalent of Day 5 of pseudopregnancy, and temporally nonsensitized uteri at Day 4 or 6; hormonally nonsensitized uteri were from animals on Day 5 treated with low or high doses of estradiol on Day 4. A cDNA with endometrial expression restricted to maximally sensitized uteri was isolated, cloned, and sequenced. The cDNA matched the sequence for glucose-regulated protein 78 (GRP78), a heat shock 70-related protein that resides in the lumen of the endoplasmic reticulum (ER) and has roles in several cellular processes including multimeric protein assembly, the degradation of proteins, and the storage and regulation of ER luminal calcium. Northern blot analysis indicated a dramatic increase in GRP78 mRNA levels restricted to the sensitized, Day 5 endometrium, suggesting a role in the onset of the sensitized phase. In situ hybridization and immunohistochemistry experiments localized the up-regulation of GRP78 within the receptive endometrium to the glandular epithelium. (+info)
Avoidance of solidification of sesame oil at low temperature by self-interesterification with immobilized lipase.
To reduce the freezing point of sesame oil, the lipase-catalyzed interesterification of sesame oil in a solvent free system was studied. The lipase was immobilized on Celite and refined sesame oil was used as the only substrate for the reaction. After interesterification, the oil did not solidify at 0 degrees C even after 24 h, and even longer storage at 2-4 degrees C did not result in solidification. The change of physical behavior was investigated with a differential scanning calorimeter and X-ray diffraction, and reduction in the thermodynamic and crystallographic stability of the interesterified oil was demonstrated. The change in triacylglycerol species composition after the reaction was analyzed, showing that content of trisaturated acylglycerol was decreased. (+info)
Estradiol modulates long-term synaptic depression in female rat hippocampus.
Fluctuating estradiol levels in the adult, female rat modify the anatomical and functional organization of the hippocampal CA1 region. When systemic levels of estradiol are low, e.g., on estrus or in ovariectomized (OVX) rats, long-term synaptic potentiation is difficult to induce in vivo. However, little is known about the role of this ovarian hormone in long-term synaptic depression. Using multiple conditioning paradigms, we assess the magnitude of long-term depression (LTD) at CA3-CA1 synapses in vitro from adult, ovariectomized rats as a function of systemic estradiol replacement. In hippocampal slices from control OVX rats with low levels of estradiol, a low-frequency (2 Hz), asynchronous conditioning stimulation protocol does not produce LTD at 1 h postconditioning. However, this same protocol induces robust LTD in slices from estradiol-treated OVX rats. When the conditioning frequency is increased to 4 Hz, slices from both groups of rats show robust LTD in vitro. At an even higher conditioning frequency (10 Hz), the 2-Hz-based observations are reversed; no consistent changes in synaptic transmission are observed in slices from estradiol-treated OVX rats, but those from control rats (OVX + oil) show robust LTD. Thus estradiol reduces the frequency threshold for LTD induction at the CA3-CA1 synapses. Further, regardless of the conditioning frequency employed, where robust LTD is seen, its induction depends on normally functioning N-methyl-D-aspartate (NMDA) receptors during conditioning. The shift in conditioning frequency needed to elicit LTD is consistent with a decrease in NMDA receptor activation with decreasing estradiol levels. (+info)
Corn and sesame oils increase serum gamma-tocopherol concentrations in healthy Swedish women.
We studied the effects of dietary intervention with three vegetable oils (Linola, corn or sesame oil, all good sources of gamma-tocopherol) on absolute and relative concentrations of alpha- and gamma-tocopherol in human serum. The oils contained only small amounts of linolenic acid but varying amounts of oleic and linoleic acids, and they had different concentrations of alpha-tocopherol. Forty healthy female students (mean age 26 y) were randomly assigned to one of three groups and consumed a diet that contained one of the three oils for 4 wk. Refined oils were distributed as ingredients in specially prepared buns, in margarine or as dressing. Serum tocopherols, serum lipoproteins and plasma malondialdehyde concentrations were measured. The gamma-tocopherol concentrations normalized to serum lipids increased significantly in the corn and sesame oil groups (P < 0.01), and the alpha-/gamma-tocopherol ratios decreased significantly from baseline concentrations in all groups (P < 0.05). The alpha-tocopherol concentrations did not change during the diet period in any of the three groups. Serum cholesterol, serum apolipoprotein B and plasma malondialdehyde concentrations decreased significantly only in the Linola oil group (P < 0.05). These data show that a moderately modified natural diet that contains both alpha- and gamma-tocopherol increases the serum gamma-tocopherol concentration in healthy women without affecting the serum alpha-tocopherol concentration. (+info)
Effects of olive, corn, sesame or peanut oil on the body weights and reproductive organ weights of immature male and female rats.
Olive, corn, sesame or peanut oil which have been used as vehicles in the immature rat uterotrophic assay or Hershberger assay, for detection of endocrine disrupting effects of environmental chemicals, was administered to ten immature female rats by subcutaneous injection from postnatal day (PND) 21 for 3 or 7 days, and each oil was also administered to ten male rats from PND 21 for 7 and 10 days. The body weights, and the weights of sex and sex accessory organs in female and male rats were measured. There were no significant differences in body weights of female rats between each oil group and the control group, while the body weight of male rats in the group given peanut or olive oil was significantly increased from 8 or 9 days after administration. There were no changes in the sex and sex accessory organ weights of female or male rats related to the endocrine disrupters. The results of the body weights and organ weights demonstrate that each oil is a suitable vehicle for the immature rat uterotrophic assay. However, each oil is suggested to be unsuitable for the Hershberger assay, because the analysis of changes of sex accessory organ weights in this assay might be confused by the increased body weights. (+info)
Evaluating the role of alternative therapy in burn wound management: randomized trial comparing moist exposed burn ointment with conventional methods in the management of patients with second-degree burns.
CONTEXT: Moist exposed burn ointment (MEBO), from China, has been said to revolutionize burn management. OBJECTIVE: Our study was conducted to compare MEBO with conventional management (C) with respect to the rate of wound healing, antibacterial and analgesic effect, and hospital costs. DESIGN: This is a prospective, randomized, controlled clinical trial conducted between 1 March 1997 and 24 October 1998. SETTING: The trial was conducted in a specialized burn facility located in a tertiary referral hospital in a developed and industrialized island-state in Southeast Asia. PATIENTS: We randomly assigned 115 consecutive patients between the ages of 12 and 80 who had partial-thickness thermal burns covering less than 40% of body surface area (BSA) to receive either MEBO or C. Fifty-seven patients were assigned to MEBO and 58 patients to C. The latter group received twice-daily dressing changes; MEBO patients received MEBO every 4 hours. MAIN OUTCOME MEASURES: Patients were hospitalized until 75% BSA had healed. BSA was determined by visual inspection and charted on Lund and Browder charts regularly. Wound healing rate, bacterial infection rate, pain score, and hospitalization costs were recorded. RESULTS: The median time to 75% healing was 17.0 and 20.0 days with MEBO and C, respectively (HR = 0.67, 95% CI = 0.41-1.11, P =.11), suggesting similar efficacy between the 2 modalities. Bacterial infection rates were similar between the 2 groups (HR = 1.10, 95% CI = 0.59-2.03, P =.76). MEBO imparted a greater analgesic effect in the first 5 days of therapy and reduced hospital costs by 8%. CONCLUSIONS: MEBO is as effective as conventional management but is not the panacea for all burn wounds. The use of MEBO eases the management of face and neck burns and facilitates early institution of occupational therapy in hand burns. It confers better pain relief such that fewer opiates are used during the first 5 days after burn injury. (+info)
Steroleosin, a sterol-binding dehydrogenase in seed oil bodies.
Besides abundant oleosin, three minor proteins, Sop 1, 2, and 3, are present in sesame (Sesamum indicum) oil bodies. The gene encoding Sop1, named caleosin for its calcium-binding capacity, has recently been cloned. In this study, Sop2 gene was obtained by immunoscreening, and it was subsequently confirmed by amino acid partial sequencing and immunological recognition of its overexpressed protein in Escherichia coli. Immunological cross recognition implies that Sop2 exists in seed oil bodies of diverse species. Along with oleosin and caleosin genes, Sop2 gene was transcribed in maturing seeds where oil bodies are actively assembled. Sequence analysis reveals that Sop2, tentatively named steroleosin, possesses a hydrophobic anchoring segment preceding a soluble domain homologous to sterol-binding dehydrogenases/reductases involved in signal transduction in diverse organisms. Three-dimensional structure of the soluble domain was predicted via homology modeling. The structure forms a seven-stranded parallel beta-sheet with the active site, S-(12X)-Y-(3X)-K, between an NADPH and a sterol-binding subdomain. Sterol-coupling dehydrogenase activity was demonstrated in the overexpressed soluble domain of steroleosin as well as in purified oil bodies. Southern hybridization suggests that one steroleosin gene and certain homologous genes may be present in the sesame genome. Comparably, eight hypothetical steroleosin-like proteins are present in the Arabidopsis genome with a conserved NADPH-binding subdomain, but a divergent sterol-binding subdomain. It is indicated that steroleosin-like proteins may represent a class of dehydrogenases/reductases that are involved in plant signal transduction regulated by various sterols. (+info)
Dietary sesame seed and its lignans inhibit 2,7,8-trimethyl- 2(2'-carboxyethyl)-6-hydroxychroman excretion into urine of rats fed gamma-tocopherol.
We showed previously that dietary sesame seed and its lignans elevate the tocopherol concentration in rats. To clarify their effect on tocopherol metabolism, we determined in this study the urinary excretion of 2,7,8-trimethyl-2(2'-carboxyethyl)-6-hydroxychroman (gamma-CEHC), a gamma-tocopherol metabolite, in rats fed sesame seed or its lignans. Rats were fed diets with or without sesame seed for 28 d in Experiment 1, and for 1, 3 and 7 d in Experiment 2. On d 28, dietary sesame seed elevated (P < 0.05) gamma-tocopherol concentrations in liver, kidney, brain and serum, and decreased (P < 0.05) urinary excretion of gamma-CEHC. The excretion was completely inhibited by feeding sesame seed on d 1 and 3. In Experiment 3, the effects of dietary sesamin and sesaminol (major lignans in sesame seed) or ketoconazole (a selective inhibitor of cytochrome P(450) (CYP)3A on urinary excretion of gamma-CEHC in rats fed gamma-tocopherol were examined. The urinary gamma-CEHC in rats fed sesamin or sesaminol was markedly lower than in rats fed gamma-tocopherol alone (P < 0.05). Dietary ketoconazole also inhibited (P < 0.05) urinary excretion of gamma-CEHC, and elevated (P < 0.05) gamma-tocopherol concentrations in tissues and serum of rats fed gamma-tocopherol. These data suggest that sesame seed and its lignans elevate gamma-tocopherol concentration due to the inhibition of CYP3A-dependent metabolism of gamma-tocopherol. (+info)