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11.
The effect of insulin and insulin deficiency on the transport and metabolism of glucose by rat small intestine 总被引:3,自引:0,他引:3
1. Insulin deficiency induced by anti-insulin serum or streptozotocin increased glucose absorption, as measured in everted sacs of rat upper ileum incubated for 30 min with oxygenated Krebs-Henseleit bicarbonate medium.2. Everted sacs prepared from the terminal ileum of insulin-deficient rats were able to accumulate glucose against a concentration gradient (i.e. development of active glucose transport).3. In experimental diabetes induced by streptozotocin, everted sacs of upper ileum showed increased 3-methyl glucose active transport, and sacs of terminal ileum showed development of 3-methyl glucose active transport.4. Lactic acid formation during the absorption of both glucose and 3-methyl glucose was increased approximately twofold in everted sacs of insulin-deficient animals.5. Insulin added at 100 mu./ml. to the incubating media of everted sacs prepared from insulin-deficient rats did not result in a reduction of glucose absorption or reverse the other effects.6. Fluoride (5 x 10(-3)M) added to the serosal and mucosal media of sacs of terminal ileum prepared from insulin-deficient rats decreased [(14)C]CO(2) formation from [U-(14)C]glucose and lactate formation during glucose absorption, but was unable to reverse the effect of insulin deficiency on glucose active transport.7. The effects of insulin deficiency induced by streptozotocin were more striking than those induced by anti-insulin serum.8. Everted sacs prepared from rats starved for 3 days showed increased glucose active transport accompanied by diminished conversion of [U-(14)C]glucose to [(14)C]CO(2).9. The possible role of hexokinase is discussed in relation to these findings. 相似文献
12.
Endothelin receptor expression in human decidua 总被引:3,自引:1,他引:3
Kohnen G; Campbell S; Irvine GA; Church HJ; MacLachlan F; Titterington M; Cameron IT 《Molecular human reproduction》1998,4(2):185-193
The endothelins are signalling peptides that act via two receptors, ET(A)
and ET(B). In the human endometrium, endothelin receptors have been
demonstrated in glands and stroma and have been shown to vary during the
course of the menstrual cycle. The present study was undertaken to
determine whether or not expression of endothelin receptors changes during
pregnancy or after administration of exogenous progestagens. The expression
of the receptors was correlated with the appearance of basement membrane
components during decidualization of the endometrial stroma. Decidual
specimens (n = 15) were obtained during the first trimester of pregnancy
and 10 at term. Sixteen pairs of endometrial biopsies were obtained from
women with menorrhagia before and after exposure to exogenous progestagens.
A total of 15 hysterectomy specimens were used as controls for the
expression of stromal basement membrane proteins in the absence of
decidualization. Autoradiography was carried out with selective ligands for
ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of
ligand binding was then compared with the distribution of laminin alpha2
light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and
collagen IV were expressed in stromal decidual cells in the first trimester
of pregnancy. ET(B) was also found on endometrial glandular epithelium.
Quantitative macro-autoradiography and multiple regression analysis
demonstrated a highly significant positive correlation (P < 0.001)
between expression of ET(B) and laminin alpha2 light chain. In the third
trimester qualitative examination suggested a reduction of ET(A) in the
stroma. Progestagen-induced decidua exhibited a similar pattern to that
found in first trimester decidua. This study has demonstrated up-regulation
of ET(B) during the progesterone- dependent process of decidualization and
suggests a paracrine or autocrine role for endothelins in the decidua.
相似文献
13.
Comer MT Andrew AC Leese HJ Trejdosiewicz LK Southgate J 《Journal of clinical pathology》1999,52(5):355-357
BACKGROUND: The assessment of neoplastic disease in gynaecological histopathology can be complicated by the high incidence of metaplasia seen in tissues of the female genital tract. There is a need to identify specific tissue markers which can be applied in routine histopathological practice. AIM: To examine the clinical potential of a monoclonal antibody, LhS28, which reacts with basal bodies of ciliated epithelial cells. METHODS: A panel of normal and pathological gynaecological tissues was processed and labelled with LhS28. RESULTS: LhS28 immunoreactivity was found in the normal Fallopian tube where it was confined to ciliated rather than secretory epithelial cells. In the remaining specimens, LhS28 was associated exclusively with ciliated cells in tubal metaplasias of the cervix and endometrium and in benign serous lined inclusion cysts. CONCLUSIONS: LhS28 may be a valuable marker for identifying metaplasia of tubal type and may find application in distinguishing tubal metaplasia from low grade cervical glandular intraepithelial neoplasia. 相似文献
14.
Induction of a differentiated ciliated cell phenotype in primary cultures of Fallopian tube epithelium 总被引:5,自引:1,他引:5
Human Fallopian tubal epithelial cells in culture lose morphological
features associated with the epithelium in situ and the extent to which
they retain their in-vivo phenotype or function is unknown. In order to
address this question, immunocytochemical markers were identified which
distinguish secretory (HMFG2+, LhS28-) from ciliated (HMFG2-, LhS28+)
epithelial cells in tissue sections of Fallopian tube. These markers were
used to analyse the phenotype of tubal cells in vitro. Primary cultures of
human tubal epithelial cells were seeded onto glass and grown to confluence
before addition of oestradiol-17beta. In the absence of hormone, tubal
epithelial cells expressed cytokeratins and nuclear receptors for oestrogen
and progesterone and adopted a homogeneous (HMFG2+, LhS28-) secretory cell
phenotype. Following the addition of oestradiol-17beta, a proportion of
cells became positive for LhS28. The induction of a ciliated epithelial
cell phenotype was confirmed by scanning electron microscopy, where on
permeable collagen membranes, approximately one-third of tubal epithelial
cells became ciliated in the presence of oestradiol-17beta. We suggest that
in vitro, tubal epithelial cells adopt an immature secretory-like phenotype
and that oestrogen can induce differentiation to a ciliated epithelial cell
phenotype.
相似文献
15.
Clinical profiling of recombinant follicle stimulating hormone (rFSH; Puregon): relationship between serum FSH and efficacy 总被引:9,自引:0,他引:9
Single-dose and multiple-rising dose studies of recombinantfollicle stimulating hormone (rFSH) in hypogonadotrophic maleand female volunteers demonstrated that the rate of FSH absorptionafter i.m. injection is higher in men than in women. In theabsence of endogenous FSH, a correlation between serum FSH andbody weight became apparent. The elimination half-life of rFSHwas not different between the sexes and was comparable withurinary FSH. However, the in-vitro bio:immuno ratio of serumFSH was significantly higher after the administration of rFSHthan after urinary FSH. When rFSH was administered daily witha fixed dose, steady state levels were reached within 3-5 days.Serum FSH concentrations increased in a dose-dependent mannerwhen the daily dose was increased weekly over 3 weeks from 75to 225 IU. In hypogonadotrophic women, rFSH induced normal folliculargrowth whereas oestrogen synthesis was impaired. In women pituitarysuppressed by a high-dose oral contraceptive, the daily administrationof 150 IU rFSH for 1 week induced more and larger antral folliclesthan the same regimen with urinary FSH, whereas the serum immunoactiveFSH concentrations measured 24 h after each dosing were similar.It is concluded that even though equal or lower serum immunoactiveFSH concentrations were obtained following the administrationof rFSH compared with urinary FSH, circulating bioactivity FSHconcentrations were higher. Therefore, the conventional ideathat serum immunoreactive FSH correlates positively with themagnitude of the ovarian response should be reconsidered. 相似文献
16.
Houghton FD Hawkhead JA Humpherson PG Hogg JE Balen AH Rutherford AJ Leese HJ 《Human reproduction (Oxford, England)》2002,17(4):999-1005
BACKGROUND: IVF is limited by low success rates and a confounding high multiple birth rate contributing to prematurity, increased neonatal mortality and child handicap. These problems could be overcome if single embryos of known developmental competence could be selected for transfer on day 2/3 of development, but current methods, which rely on morphological appearance, are poor predictors of viability. METHODS: We have measured non-invasively the depletion/appearance (i.e. turnover) of a physiological mixture of 18 amino acids by single human embryos during in-vitro culture using high performance liquid chromatography. RESULTS: From the time of transfer (day 2/3), embryos with future competence to develop to the blastocyst stage (day 5/6) exhibit amino acid flux patterns distinct from those of embryos with similar morphological appearance which arrest. Significantly, the profiles of Ala, Arg, Gln, Met and Asn flux predict blastocyst potentiality at >95%. The amino acid most consistently depleted throughout development by those embryos which form blastocysts was leucine. Of the amino acids which were produced, the most striking was alanine, which appeared in increasing amounts throughout development. CONCLUSIONS: Non-invasive amino acid profiling has the potential to select developmentally competent single embryos for transfer, thereby increasing the success rate and eliminating multiple births in IVF. 相似文献
17.
18.
Richard D Neal Victoria L Allgar Nasreen Ali Brenda Leese Phil Heywood Gill Proctor Joyce Evans 《The British journal of general practice》2007,57(536):212-219
BACKGROUND: Very few studies have reported cancer outcomes of patients referred through different routes, despite the prominence of current UK cancer urgent referral guidance. AIM: This study aimed to compare outcomes of cancer patients referred through the urgent referral guidance with those who were not, with respect to stage at diagnosis, survival, and delays in diagnosis. Design of study: Analysis of hospital records. SETTING: One hospital trust in England. METHOD: The records of 889 patients diagnosed in 2000-2001 with one of four types of cancer were analysed: 409 with lung cancer; 239 with colorectal cancer; 146 with prostate cancer; and 95 with ovarian cancer. Outcome measures were diagnostic stage, survival, referral and secondary care delays. RESULTS: For lung cancer, urgent referrals had more advanced TNM (tumor, node, metastasis) stage than patients diagnosed through other routes (P = 0.035) and poorer survival (P = 0.020). There was no difference in stage or survival for the other cancers. For each cancer, a higher proportion of urgent referrals was seen within 2 weeks. Secondary care delays for lung and colorectal cancer were shorter for inter-specialty referrals. CONCLUSION: For patients with lung cancer, the guidance appears to be prioritising those in the more advanced stages of disease. This was not the case for the other three cancers. Referral delays were shorter for patients urgently referred, as is the intention of the guidance. The avoidance of delays in outpatient diagnostics probably accounts for shorter secondary care delays for inter-specialty referrals. 相似文献
19.
Houghton F.D.; Hawkhead J.A.; Humpherson P.G.; Hogg J.E.; Balen A.H.; Rutherford A.J.; Leese H.J. 《Human reproduction (Oxford, England)》2003,18(8):1756-1757
Non-invasive amino acid turnover predicts human embryo developmentalcapacity By F.D.Houghton, J.A.Hawkhead, P.G.Humpherson, J.E.Hogg, A.H.Balen,A.J.Rutherford and H.J.Leese Hum. Reprod., 17, 9991005, 2002 Errors have been found in the above paper and the correctionsare given below. Due to a calculation error, the amino acid values presentedfor 17 of the 18 amino 相似文献
20.
C J Falliers M L Brandon E Buchman J T Connell R Dockhorn P T Leese J Miller S I Wasserman J M Zeterberg R Altman 《Annals of allergy》1991,66(3):257-262
The efficacy and safety of cetirizine were evaluated in 419 patients with seasonal allergic rhinitis. Using a 4-way, double-blind randomization schedule, patients were given a 1-week course of once daily cetirizine (5, 10, or 20 mg) or placebo. Patient and physician efficacy ratings corresponded, indicating superiority of cetirizine to placebo (P less than .05) in reducing symptom severity scores for sneezing, rhinorrhea, ocular pruritus, nasal pruritus, watering of the eyes, and redness of the eyes. All cetirizine doses achieved higher efficacy ratings (72.7%, 79.2%, and 75.7%, respectively) than placebo (52.9%; P less than .05) by the physician's global assessment. Cetirizine was well tolerated, with sedation being the most common adverse experience, increasing in frequency at higher doses. A dose-response relationship was evident for selected symptoms, and the once daily 5-mg dose was found to be an effective minimum dose. 相似文献