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1.
Genomic constructs comprising the ovine β-lactoglobulin gene are expressed in a position-independent manner in the mammary gland of transgenic mice. In some lines however, constitutive low-level transgene expression was detected in all other tissues. This ectopic expression presumably represents a position-dependent phenomenon since it was observed in only a proportion (40%) of the lines generated. Different lines of BLG transgenic mice displayed similar temporal patterns of ectopic expression. This pattern differed from that of BLG in the mammary gland. These data imply that the DNA elements that direct position-independent expression of β-lactoglobulin transgenes in the mammary gland do not have the ability to insulate them from position effects in other tissues. Furthermore, the relatively high frequency and constitutive nature of ectopic expression suggests that transgene integration may not be totally random.  相似文献   

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《Endocrine practice》2008,14(6):757-763
ObjectiveTo review the underlying causes of pituitary lesions, a rational approach to their diagnosis, and therapeutic options.MethodsThe types of pituitary lesions and their clinical manifestations are reviewed, and treatment strategies and long-term follow-up are discussed.ResultsA pituitary adenoma is quite common and poses a challenge to the clinician to determine the clinical significance, the appropriate diagnosis, the need for treatment, and the appropriate therapy or therapies. The treatment of a pituitary adenoma depends on the type of tumor; a prolactinoma is treated medically with a dopamine agonist drug, and other lesions are usually treated by transsphenoidal surgical removal. Replacement of a deficient hormone or hormones is necessary for optimal functioning. Some patients require more than one treatment, including surgical intervention, replacement of a hormone or hormones, medications to lower hormone hypersecretion to normal (for prolactinoma, acromegaly, or Cushing disease), pituitary radiation therapy (optimally with focused irradiation such as the Gamma Knife or LINEAC), and, in the situation of persistent Cushing disease, bilateral adrenalectomy as a last resort. Lifelong monitoring is necessary for all these patients.ConclusionThe goal is to decrease the mass effect of the adenoma, to restore normal pituitary function, and to suppress hormone hypersecretion. Achievement of this goal necessitates the cooperation and interdisciplinary efforts of several medical specialties. (Endocr Pract. 2008;14:757-763)  相似文献   

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Genetically modified mice have been widely used in the field of β-cell research. However, analysis of results gathered using genetically modified organisms should be interpreted carefully as the results may be confounded by several factors. Here, we showed the ectopic serotonin (5-HT) production in β-cells of RIP-CreMgn, MIP-GFP, and MIP-Cre/ERT mice. These mice contained a human growth hormone (hGH) cassette to enhance transgene expression and hGH expression and Stat5 phosphorylation were detected in pancreatic islets of these mice. The expression level of tryptophan hydroxylase 1 (Tph1) was upregulated in pancreatic islets of transgenic mice with an hGH cassette but not in transgenic mice without an hGH cassette. Ectopic 5-HT production was not observed in β-cell-specific prolactin receptor (Prlr) knockout mice or Stat5 knockout mice crossed with RIP-CreMgn. We further confirmed that 5-HT production in β-cells of several transgenic mice was induced by hGH expression followed by the activation of the Prlr-Stat5-Tph1 pathway. These findings indicate that results obtained using transgenic mice containing the hGH cassette should be interpreted with care.  相似文献   

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The relative regulatory roles of the pituitary gonadotropins, luteinizing hormone and follicle stimulating hormone in the spermatogonial proliferation has been studied using specific antibodies against these hormones in the immature rats. Immunoneutralization of lu teinizing hormone for 7 days resulted in significant reduction in tetraploid cells and total absence of haploid cells,while there was a relative increase in the diploid population. This was also accomopanied by a decrease in spermatogonial proliferation as indicated by a decrease in [3H] thymidine incorpor-ation into DNA by purified spermatogonia. Administration of follicle stimulating hormone a/s for 7 days also caused a significant decrease in the rate of spermatogonial proliferation. Withdrawal of follicle stimulating hormone led to a significant reduction in tetraploid and haploid cells. However interestingly,it failed to totally abolish the appearance of these cells. Administration of testosterone (3 mg/day/rat) for 2 days along with the gonadotropin a/s could partially reverse the effect on spermatogonial proliferation. It is concluded that (i) both luteinizing hormone and follicle stimulating hormone are involved in spermatogonial proliferation, (ii) lack of testosterone consequent of the neutralization of luteinizing hormone prevented the entry of spermatogonial cells into meiosis, (iii) testosterone may be involved in spermatogonia] proliferation providing a mitotic signal and (v) both follicle stimulating hormone and testosterone act synergistically and lack of any one of the hormones results in impairment of spermatogonial proliferation. A part of the data was presented at the 16th International Congress of Biochemistry and Molecular Biology, New Delhi, September 1994.  相似文献   

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lsd (lysergic acid diethylamide) is a powerful bio-active substance related to serotonin in structure. Its actions generally affect autonomic, sensory and psychological functions. Autonomic stimulation is varied. Sensory responses are usually visual, involving heightened and distorted color perception and fusion of sensory impressions. Psychological responses include a feeling that a unique experience is occurring; feelings of depersonalization; pronounced fluctuation of mood; time and space distortions; autistic phenomena; fluctuation of aggressive drives (usually reduction); and spontaneous reoccurrence of the lsd experience.The subjective responses can be related to three basic phenomena: (1) expectation; (2) loss of characteristic modes of perceptual and cognitive patterning; and (3) hypersuggestibility.The major adverse reactions are: (1) chronic drug dependence including subsequent personality changes and depressive reactions; and (2) acute ego dissolution. These reactions usually occur in already emotionally ill people. Most of these users fall into two groups, those with unresolved identity problems and those with severe ego abnormality. The majority of adverse reactions are of the chronic drug dependence type and are usually seen in adolescents and young adults who have not negotiated the age-appropriate tasks of forming and integrating the various identities that are the composite of their life experiences.lsd helps alleviate these stresses via some of its psychological properties as discussed. It also provides a nidus for the formation of a subculture where goals for social, sexual and vocational achievement are lower and idiosyncratic modes of adaptation are better tolerated. A smaller group of users who have serious reactions such as psychosis, rage reactions, homicidal and suicidal ideation are usually found to have preexisting ego abnormality such as ambulatory schizophrenia, chronic impulse disorders and borderline states. Although adverse reactions most often appear to be related to pre-morbid psychopathology, this is not invariably so. Further, there is as yet no reliable method to determine who will have an adverse reaction and what the nature of that reaction will be.  相似文献   

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Data concerning the presence in the central nervous system of the anterior and intermediate lobe hormones ACTH, beta-lipotropin, alpha-melanocyte stimulating hormone, beta-endorphin, prolactin, growth hormone, gonadotrophic hormone, and thyrotropin stimulating hormone are reviewed. Available evidence for the ACTH-lipotropin family of peptides indicates that synthesis can occur in brain as well as in pituitary. Although behavioral effects have been described for some of these peptides and their fragments (ACTH, alpha-MSH, beta-endorphin, prolactin), the physiological relevance and the mechanisms of such effects, the nature of the biosynthetic pathways involved, and the factors regulating the brain concentrations of these peptides remain to be explored.  相似文献   

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Primary Sjo¨gren's syndrome(p SS) is a systemic autoimmune disease with exocrine gland dysfunction and multi-organ involvement. Recent progress in understanding the pathogenesis of p SS offers an opportunity to find new biomarkers for the diagnosis and assessment of disease activity. Screening noninvasive biomarkers from the saliva and tears has significant potential. The need for specific and sensitive biomarker candidates in p SS is significant. This review aims to summarize recent advances in the identification of biomarkers of Sjo¨gren syndrome, trying to identify reliable, sensitive, and specific biomarkers that can be used to guide treatment decisions.  相似文献   

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Twenty-two patients with Sjögren''s syndrome uncomplicated by a connective tissue disorder, 31 with Sjögren''s syndrome complicated by rheumatoid arthritis, and 21 with rheumatoid arthritis alone were studied with particular reference to changes in the ears and in the upper respiratory and digestive tracts.Epistaxis, soreness and dryness of the throat, dysphagia, and hoarseness were common symptoms, and rhinitis sicca and postcricoid narrowing were not uncommon features of the Sjögren groups. Oesophagoscopy in one patient revealed a web identical to that found in Paterson/Brown Kelly syndrome; none of the patients, however, had an iron-deficiency anaemia or koilonychia. There was an increased frequency of deafness in all groups, and the deafness tended to be conductive in the Sjögren groups and sensorineural in the rheumatoid arthritis group.  相似文献   

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《Anaerobe》2001,7(3):151-158
Papillon LeFèvre Syndrome, or PLS, was first described over 70 years ago. It is characterised by severe periodontal disease, typically leading to loss of teeth by adolescence, combined with palmoplantar hyperkeratosis. The fact that it is associated with consanguinity in particular ethnic groups suggests that genotype may contribute to the aetiology of this syndrome. Microbiological studies have been hampered by the rareness of the condition which makes prospective studies virtually impossible to perform. Numerous studies on small groups of patients, sometimes single cases, together suggest an association of recognised periodontal pathogens with PLS. Actinobacillus actinomycetemcomitans has been especially linked to PLS and raised levels of antibody to A.a. have been measured in some PLS patients, though not others. Porphyromonas gingivalis and Prevotella intermedia have also been detected in plaque samples from PLS, using monoclonal antibodies. Many other species have also been associated with PLS following culture and identification, as well as use of probes. Treatment has been attempted by eradication of periodontal pathogens so that teeth can erupt into a ‘safe’ environment. Successful treatment has needed intensive treatment and monitoring and good oral hygiene as well as thorough antibiotic therapy of patient, family members and even pets. Recently a Cathepsin C genotype has been strongly linked to PLS. However, this gene cannot account for all features of PLS and we can speculate that additional genes must be involved. It is concluded that PLS results from a combination of host and bacterial factors, including recessive human gene(s) associated with consanguinity, specific periodontal pathogens and lack of thorough oral hygiene. It is also believed that the human genetic component may merit examination as a ‘host factor’ in other bacterial infections.  相似文献   

13.
The availability and efficacy of prostaglandin (PG) F2 alpha and E series analogues has prompted their frequent use for pregnancy interruption. In the course of evaluating our experience with PGs for interrupting early first trimester gestations, we became increasingly impressed by the absence of any with extrauterine pregnancy. A review of 63 reports encompassing 2,965 patients whose pregnancies were less than 8 weeks' gestational age dating from the last menstrual period and who were similarly treated yielded only 2 cases of ectopic pregnancy. When compared with the generally accepted ectopic gestation rates of the order of 1 in 200 pregnancies, this frequency of 1 in 1,483 is unexpectedly low. Preselection does not appear to explain this impressive discrepancy. If the observation proves correct, it implies that PGs have some form of therapeutic effect in eradicating extrauterine pregnancy by nonoperative means. The implications are obvious in terms of its potential therapeutic benefits.  相似文献   

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Syndromic conditions with overgrowth as the cardinal clinical sign are a relevant problem in human genetics and pediatrics. Overgrowth is defined as a length/height of more than two standard deviations above the mean, i.e. a body length above the 97th centile. Overgrowth syndromes relevant in the clinical daily routine of the geneticist or pediatrician are described here: Marfan, Beckwith-Wiedemann, Sotos, Weaver, Simpson-Golabi-Behmel and Proteus syndromes. The characteristic clinical signs, diagnostic criteria, molecular bases, modes of inheritance, prevention programs—where necessary—as well as differential diagnoses are presented here.  相似文献   

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The lack of a pituitary imaging agent combined with the considerable clinical value for such an agent prompted an examination of 3H-spiroperidol (3HSp). Spiroperidol was selected for initial evaluation based on its high affinity for D2 receptors which are known to be present in the pituitary. A time course study of 3HSp concentration in rat pituitary and other tissues was conducted. Pituitary activity levels were found to be constant from 5 min to 4 h and were about 8 times levels in corpus striatum at 1 h. Blocking studies with (+)-butaclamol and with unlabelled spiroperidol suggested the existence of both a D2 receptor mediated binding localization and a second uptake which is postulated to be an internalization process. Further studies involving ultracentrifugation of pituitary homogenates resulted in evidence for association of 3HSp with dense subcellular particles. 3HSp thus appears to be internalized by pituitary cells.  相似文献   

17.
A receptor for angiostatin was identified on the surface of endothelial cells as F1–F0 ATP synthase (Moser et al., 1999). Proc. Natl. Acad. Sci. U.S.A. 96, 2811–2816. This ectopic ATP synthase catalyzes ATP synthesis and is inhibited by angiostatin over a wide pH range. Endothelial cells grown at normal pH suffer no ill effects from this angiostatin-mediated inhibition of ATP synthase, whereas endothelial cells grown at low, tumor-like extracellular pH cannot maintain a normal intracellular pH and die. Angiostatin inhibits both ATP synthesis and ATP hydrolysis (Moser et al., 2001) and interferes with intracellular pH regulation (Wahl and Grant, 2002; Wahl et al., 2002). Although angiostatin administered intravenously is cleared from the circulation in a matter of minutes, angiostatin-mimetics that are more stable have potential for clinical application. An angiostatin-mimetic activity has recently been observed using a polyclonal antibody against the β catalytic subunit of ATP synthase. In order to explore the mechanism of action of angiostatin and its mimetics, further work needs to be done to evaluate clinical applicability, specificity, and contraindications for this class of therapeutics.  相似文献   

18.
Handling is a source of stress for farm bred blue foxes. The influence of handling during the late gestation period on the pituitary–adrenal axis was studied in 10-day old male and female blue foxes. Cortisol and progesterone were measured by radioimmunoassay in the plasma, adrenal homogenates, and in vitro incubates from animals of both sexes. Adrenals were incubated in vitro in the absence or presence of ACTH. In addition, the adrenal weight and plasma concentration of ACTH were assessed. In cubs of both sexes, the adrenal weight was decreased after prenatal stress treatment. The plasma concentration of progesterone and the adrenal cortisol in vitro production were elevated in the prenatally stressed female cubs, as compared to the control, along with the adrenal progesterone in vitro production in prenatally stressed male cubs. The adrenal cortisol and progesterone content and plasma ACTH and cortisol concentrations were not affected by prenatal stress. In conclusion, the results of this study suggest that the prenatal stress induced by handling pregnant vixens can affect the pituitary–adrenal axis in neonatal offspring, this effect being more pronounced in female cubs.  相似文献   

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This article reviews the relationship between metabolic syndrome (MetS) and nephrolithiasis, as well as the clinical implications for patients with this dual diagnosis. MetS, estimated to affect 25% of adults in the United States, is associated with a fivefold increase in the risk of developing diabetes, a doubling of the risk of acquiring cardiovascular disease, and an increase in overall mortality. Defined as a syndrome, MetS is recognized clinically by numerous constitutive traits, including abdominal obesity, hypertension, dyslipidemia (elevated triglycerides, low high-density lipoprotein cholesterol), and hyperglycemia. Urologic complications of MetS include a 30% higher risk of nephrolithiasis, with an increased percentage of uric acid nephrolithiasis in the setting of hyperuricemia, hyperuricosuria, low urine pH, and low urinary volume. Current American Urological Association and European Association of Urology guidelines suggest investigating the etiology of nephrolithiasis in affected individuals; however, there is no specific goal of treating MetS as part of the medical management. Weight loss and exercise, the main lifestyle treatments of MetS, counter abdominal obesity and insulin resistance and reduce the incidence of cardiovascular events and the development of diabetes. These recommendations may offer a beneficial adjunctive treatment option for nephrolithiasis complicated by MetS. Although definitive therapeutic recommendations must await further studies, it seems both reasonable and justifiable for the urologist, as part of a multidisciplinary team, to recommend these important lifestyle changes to patients with both conditions. These recommendations should accompany the currently accepted management of nephrolithiasis.Key words: Nephrolithiasis, Metabolic syndrome, Uric acid nephrolithiasisMetabolic syndrome (MetS), as defined by the National Cholesterol Education Program and the Adult Treatment Panel III in 2001 (and updated in 2005), represents a growing medical problem affecting more than 22% of US adults.14 It is associated with an almost fivefold increase in the risk of developing diabetes and a doubling of the risk of acquiring cardiovascular disease.5 MetS is a clinical disorder defined by the presence of at least three of the following criteria: central obesity (abdominal girth > 102 cm [40 in] men and > 88 cm [35 in] women), low high-density lipoprotein (HDL) cholesterol (< 40 mg/dL in men and < 50 mg/dL in women), hypertriglyceridemia (> 150 mg/dL), hypertension (blood pressure > 130/85 mm Hg), and elevated fasting glucose (> 100 mg/dL).2,4 The development of MetS appears to result from a complex interaction of genetics, phenotypic visceral fat accumulation (central obesity), insulin resistance, and sedentary behavior.5,6 Beyond cardiometabolic risks, MetS has a wide range of long-term complications, including nonalcoholic fatty liver disease, polycystic ovarian syndrome, obstructive sleep apnea, hypogonadism, lipodystrophy, microvascular disease, and chronic renal disease.6 An important urologic complication of MetS, not routinely cited, is nephrolithiasis.68Nephrolithiasis continues to be a major cause of morbidity and healthcare spending.9 A history of kidney stones is approximately twice as common in individuals with three criteria for MetS and three times as common in those with five criteria for MetS, as compared with those with none.10 These trends were confirmed in a large-scale, nationwide study of 30,448 Japanese patients with urolithiasis, who demonstrated that MetS was associated with a significantly increased risk of hypercalciuria, hyperuricosuria, hyperoxaluria, and hypocitraturia, independent of age and sex.11 Additionally, patients with a history of nephrolithiasis are significantly more likely to have multiple risk factors for cardiovascular disease, premature atherosclerosis, and cardiovascular events.10,12,13 It is unknown whether this is primarily a reflection of factors associated with nephrolithiasis, such as obesity, hypertension, or glucose intolerance/diabetes, or due to components of MetS, such as insulin resistance.14 The current American Urological Association (AUA) guidelines on the medical management of kidney stones suggests a need for future research on advising patients to exercise and lose weight, but does not make definitive recommendations on these lifestyle changes.15  相似文献   

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