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1.
We have evaluated the effect of oral administration of arginine chlorhydrate on the growth hormone response to growth hormone releasing hormone in a group of nine short prepubertal children (six boys and four girls). Arginine chlorhydrate 10 g, administered orally 60 min before an i.v. bolus injection of growth hormone releasing hormone 1-29, 1 microgram/kg, significantly enhanced the growth hormone response to the neuropeptide, confirming the results of previous studies which used the i.v. route. Furthermore, our data strengthen the view that the effects of arginine chlorhydrate on growth hormone secretion are mediated by inhibition of endogenous somatostatin release.  相似文献   

2.
Subjects ranging in age from 50 to 89 years old, either with or without dementia were studied by both ELISA for anti-human T-cell lymphotropic virus type I (HTLV-I) gag 100-130 antibody and by cranial CT in order to clarify the relationship between HTLV-I infection and dementia. The frequency of anti-HTLV-I antibody was found to be significantly higher in the patients with dementia (24/130, 18.5%) than in those without dementia (11/139, 7.9%) (P=0.0169). Among the various types of dementia, HTLV-I seropositivity was found to be significantly associated with vascular dementia (11/48, 23%) (P=0.0087), but not with Alzheimer type dementia. In addition, HTLV-I seropositivity was also associated with Babinski sign, and the severity of cerebral infarction, ventricular dilatation and periventricular lucency on CT. The presence of HTLV-I therefore appears to be one of the risk factors for vascular dementia in HTLV-I endemic areas.  相似文献   

3.
The effect of GH administration was evaluated over 2 yr in 50 short, prepubertal, non-GH deficient children born small for gestational age, who had been randomly allocated to a group receiving no treatment or daily sc GH treatment at a dose of 0.2 or 0.3 IU/kg. At the start of the study, mean age was 5.2 yr, bone age was 4.0 yr, height SDS was -3.5, height velocity SDS was -0.8, weight SDS was -2.7, and body mass index SDS was -1.9. Catch-up growth was observed in none of the untreated and all of the treated children. The response to GH treatment included a near doubling of growth velocity and of weight gain and a mean height increment of more than 2 SDS. GH treatment was associated with a distinct acceleration of bone maturation. The differences between the growth responses evoked by the two GH doses were minor. The prepubertal GH-induced catch-up growth was associated with elevated serum concentrations of insulin, insulin-like growth factor-I, insulin-like growth factor binding protein-3, and osteocalcin, whereas insulin-like growth factor-II levels remained unaltered. GH treatment was well tolerated. In conclusion, high-dose GH administration over 2 yr is emerging as a potential therapy to increase the short stature that results from insufficient catch-up growth in young children born small for gestational age. The long-term impact of this approach remains to be delineated.  相似文献   

4.
OBJECTIVE: To study the influence of continuous administration of heparin on platelet function in intensive care patients. DESIGN: Prospective, serial investigation. SETTING: Clinical investigation on a surgical and neurosurgical intensive care unit in a university hospital. PATIENTS: The study included 45 patients: 15 postoperative with patients sepsis (Acute Physiology and Chronic Health Evaluation II score between 15 and 25), 15 trauma patients (Injury Severity Score 15 to 25), and 15 neurosurgical patients. INTERVENTIONS: Management of the patients was carried out according to the guidelines for modern intensive care therapy. Sepsis and trauma patients received standard (unfractionated) heparin continuously [aim: an activated partial thromboplastin time (aPTT) approximately 2.0 times normal value; sepsis-heparin and trauma-heparin patients], whereas neurosurgical patients received no heparin (neurosurgical patients). MEASUREMENTS AND RESULTS: From arterial blood samples, platelet aggregation was measured by the turbidimetric method. Platelet aggregation was induced by adenosine diphosphate (ADP; 2.0 mumol/l), collagen (10 micrograms/ml), and epinephrine (25 mumol/l). Measurements were carried out on the day of diagnosis of sepsis or 12 h after hemodynamic stabilization (trauma and neurosurgery patients) (baseline) and during the next 5 days at 12.00 noon. Standard coagulation parameters [platelet count and fibrinogen and antithrombin III (AT III) plasma concentrations] were also monitored. Heparin 4-10 U/kg per h (mean dose: approximately 500 U/h) was necessary to reach an aPTT of about 2.0 times normal. Platelet count was highest in the neurosurgical patients, but it did not decrease after heparin administration to the trauma and sepsis patients. AT III and fibrinogen plasma levels were similar in the three groups of patients. In the sepsis group, platelet aggregation variables decreased significantly (e.g., epinephrine-induced maximum platelet aggregation:-45 relative % from baseline value). Platelet function recovered during the study and even exceeded baseline values (e.g., ADP-induced maximum platelet aggregation: +42.5 relative % from baseline value). Continuous heparinization did not blunt this increase of platelet aggregation variables. In the heparinized trauma patients, platelet aggregation variables remained almost stable and were no different to platelet aggregation data in the untreated neurosurgical patients. CONCLUSIONS: Continuous administration of heparin with an average dose of approximately 500 U/h did not negatively influence platelet function in the trauma patients. Recovery from reduced platelet function in the sepsis group was not affected by continuous heparinization. Thus, continuous heparinization with this dose appears to be safe with regard to platelet function in the intensive care patient.  相似文献   

5.
Macrophages are important constituents of the immune system by exerting phagocytosis on invading pathogens as well as secreting various immunoregulatory factors. Generation of human macrophage hybridoma has not been possible so far due to the lack of an appropriate fusion partner cell line. In the present study, an 8'-azaguanine resistant cell line, termed HL-60R, was established by drug selection of the promyelocytic cell line HL-60. This novel cell line showed resistance to high concentrations of 8'-azaguanine and was sensitive to aminopterin. These characteristics make it suitable for serving as a potential fusion partner cell line in the development of macrophage hybridoma. Cell-surface analysis by FACS revealed that HL-60R cells per se do not express MHC-class II molecules or the macrophage marker, CD11b. PEG-mediated fusion of HL-60R was performed with PBMC-derived human macrophages. Fluorescence labelling of ex vivo isolated macrophages prior to fusion and subsequent FACS analysis showed that PEG-4000 is a more effective fusion agent than PEG-1500. The generation of this novel fusion partner cell line opens the possibility for development of human macrophage hybridoma or other cell lines from myelocytic origin. Such hybridoma clones will not only enable a more convenient study of these cell but will also provide an excellent host site for the proper production and expression of various recombinant proteins from myelocytic origin in vitro.  相似文献   

6.
The authors present the methodology and the results of a trial of 3D-reconstruction of the fibrous frame of the rotator cuff taken from high resolution MRI. The accuracy of the method used is discussed. A precise reconstruction of the soft tissues is possible and provides an interesting model to study the mechanical role of the rotator cuff muscles. An example of biomechanical application of the 3D images is given.  相似文献   

7.
8.
OBJECTIVE: To find out whether leptin can attenuate hypometabolic torpor-like states of metabolic rate (MR) in adult lean animals, as it attenuates the morning suppression of thermoregulatory thermogenesis in suckling-age rat pups. DESIGN: Leptin effects on MR and food intake were studied in mice aged 4-7 months, in which a high incidence of exaggerated circadian reductions of MR had been induced by chronic food-restriction and, for comparison, in free-feeding mice. PROTOCOL: Continuous recordings of MR, for a group of seven mice maintained at an ambient temperature of 24 degrees C, while they were repeatedly-with pauses of at least six days-treated for three consecutive days with either recombinant murine leptin (20, 200 or 600 pmol x g(-1) x d[-1]) or saline. RESULTS: Leptin treatment caused dose-dependent 5-15% increases in energy expenditure by moderating the decreases in MR during the circadian minima, without affecting either the MR during the circadian maxima or food intake. Similar treatment of free-feeding mice caused dose-dependent decreases of food intake without changing MR. CONCLUSION: Leptin controls thermoregulatory energy expenditure when food supplies are scarce and changes food intake, rather than energy expenditure, when food is abundant.  相似文献   

9.
The effects of growth hormone (GH) therapy on biochemical markers of bone turnover were investigated in 11 short prepubertal children without GH deficiency by measuring serum osteocalcin, a marker for bone formation, and urinary concentrations of pyridinium cross-linked amino acids of collagen (PCL), and the peptide-bound pyridinoline residue N-telopeptide (NT), which are specific markers for bone resorption. GH treatment for three months increased bone turnover in this group of children: urinary PCL concentrations increased from 69 +/- 6.2 to 114 +/- 9.3 nmol/mmol Cr (p < 0.01), and urinary NT levels increased from 512 +/- 65 to 766 +/- 74 pmol BCE/mumol Cr (p = 0.058). Serum osteocalcin concentrations increased from 13.64 +/- 2.57 ng/ml to 26.45 +/- 1.39 ng/ml (p < 0.01). The increment in 12-hour urinary concentrations of PCL was highly correlated with the increment in 12-hour urinary NT levels (r = 0.92, p < 0.01). Stepwise multiple regression analysis revealed that the urinary concentrations of NT after 3 months of GH therapy were the best predictor of growth after 12 months of treatment (r = 0.78, F = 7.9, p = 0.037).  相似文献   

10.
Four estrous beagles were inseminated with 1 x 10(8) sperm into both the right and left uterine horns, and the uterine horn and oviduct on one side were removed under anesthesia after 7 hr and 24 hr, respectively. The lumen of the uterine horns and oviducts was flushed with canine capacitation medium (CCM), and movement of the sperm in CCM was assessed by phase-contrast microscopy. In a second experiment, ejaculated sperm obtained from 5 normal beagles was incubated in CCM supplemented with oviductal flush fluid (OF-CCM) at 38 degrees C with 5% CO2 in air. Motility of sperm, and percentages of hyperactivated sperm (%HA) and acrosome-reacted sperm (%AR) among freely swimming (FS) sperm were investigated until 24 hr after the start of incubation. After 7 hr of incubation the sperm was coincubated with canine oocytes in OF-CCM for 2 hr, and the number of zona pellucida-binding (zona-binding) sperm was then counted. The %HA among the sperm in the oviductal flush fluid both 7 hr (mean +/- S.E.; 15.0 +/- 2.4%) and 24 hr (77.5 +/- 5.2%) after intrauterine insemination were significantly higher than in the uterine flush fluid (P < 0.05, 0.01, respectively). The motility and %HA among FS-sperm in OF-CCM were higher than in the control medium without oviductal fluid. However, there was no difference in the %AR between OF-CCM and control medium. The number of zona-binding sperm in OF-CCM (8 +/- 1) was significantly greater than in control medium (5 +/- 1) (P < 0.05). These results suggest that oviductal fluid in the estrous bitch maintains sperm motility and induces sperm capacitation.  相似文献   

11.
FSH has four asparagine-linked oligosaccharides with variable sialic acid contents, so that FSH is not a single molecule, but a heterogeneous group of isoforms. These isoforms differ in their biological properties and their distribution changes in various physiological states, allowing the modulation of FSH activity. Recombinant human (h) FSH has been produced in Chinese hamster ovary cells and has an isoform profile similar to those of both pituitary FSH standard and purified urinary FSH. These FSH preparations, however, do not contain the full spectrum of FSH isoforms found in the circulation. Production of recombinant hFSH in a cell line with a different pattern of glycosylation could broaden its isoform profile and potentially alter its biological activity. Thus, we transfected human embryonal kidney cells (293) with the human alpha and FSH beta genes to produce recombinant hFSH (hFSH-293) and determined its biological activity in a rat granulosa cell bioassay. Although hFSH-293 was immunologically indistinguishable from pituitary FSH standard, its biological potency was 3- to 6-fold higher than those of two different pituitary FSH standards. To investigate this increased potency, we separated the isoforms of hFSH-293 by chromatofocusing and determined their biological potencies in the rat granulosa cell bioassay. The isoform profile of hFSH-293 demonstrated a greater number of basic isoforms than that of pituitary FSH standard. Several of these basic isoforms exhibited enhanced in vitro biological potency, accounting for the increased biological potency of hFSH-293. This pattern of high in vitro biological activity and more basic isoforms is analogous to the FSH circulating during GnRH stimulation, pubertal induction, and ovulation.  相似文献   

12.
The purpose of this preliminary study was to evaluate tooth formation in children with idiopathic short stature, before and during treatment with recombinant growth hormone (rhGH). Twenty-nine short-statured children ages 6 to 13 years were assigned into two treatment groups, an "experimental" group (n = 18), which received rhGH, and a "control" group (n = 11), which was observed for 1 year before commencing rhGH treatment. Clinical and radiographic records were obtained at the initial, year 1, and year 2 visits. Tooth formation and stature were assessed by calculating Z-scores, appropriate for the age and gender of each child. Delta-Z scores, which measure the change in Z-score over time, were also calculated between annual visits. Height was measured and recorded every 3 months, and Z-score statural norms for age and gender were derived from the 1977 National Center for Health Services national probability sampling. Tooth formation standards were derived from Moorrees et al. A matched control sample for tooth development was derived from untreated children. Tooth formation was initially delayed although the degree of reduction in stature exceeded the initial degree of delay in tooth formation. During this 2-year study, rhGH therapy had a significant influence on acceleration or gain in stature, but did not have a significant influence on tooth formation.  相似文献   

13.
Tuberculosis of the cervical spine is rare, comprising 3-5% of cases of tuberculosis of the spine. Eight patients with tuberculosis of the cervical spine seen during 1989-1992 were reviewed. They all presented with neck pain. The 4 children presented with a kyphotic deformity. In all the children the disease was extensive, with a large prevertebral abscess formation, while in the adults it was localised to one or two motion segments. Cord compression was present in 4 of the 8 patients. All the patients were treated with antituberculosis drugs and 6 underwent surgery. There was full neurological recovery in all patients. The kyphosis was improved though not fully corrected. There was a problem in stabilisation of severe involvement of the body and dens of C2. Surgery seems to play a major role in the treatment of tuberculosis of the cervical spine.  相似文献   

14.
The introduction of human growth hormone (GH) prepared by recombinant DNA technology has resulted in increased numbers of children and adults receiving treatment. This trend has led to questions concerning the safety of GH, particularly when used for indications other than GH deficiency. This review discusses the effects of GH on fluid, lipid, and carbohydrate metabolism; the risk of intracranial hypertension or pseudotumor cerebri; the effects on the skeletal system; the risk of malignancy; and the effects on the immune system. At present, GH treatment appears to be safe, although long-term follow-up of GH-treated patients is necessary.  相似文献   

15.
Carbon sources that can be converted to acetate were added to the growth medium of Escherichia coli wild-type cells. Cells responded with an increased cell division rate. The addition of acetate also caused a decreased synthesis of flagella. Mutants in phosphotransacetylase, which are incapable of synthesizing acetyl phosphate, and mutants in the osmoregulator OmpR divided at a lower rate than did wild-type cells. The mutants did not increase their cell division rate upon the addition of serine, as observed for wild-type cells. These data are consistent with the idea that the previously described effect of serine upon the cell division rate is mediated by acetyl phosphate and phosphorylation of OmpR.  相似文献   

16.
It is not known whether a short loop feedback mechanism for the regulation of LH exists in sheep. This study on ovariectomized ewes investigated whether a bolus injection (10, 1, and 0.1 microg LH or 1 microg BSA; n 4) or a 3-h continuous infusion of exogenous LH (100 or 1 ng/min; n = 7) into the third ventricle through a permanent indwelling cannula could influence the activity of the GnRH pulse generator, as determined by measurement of endogenous LH secretion. To assess the potential for involvement in a LH short loop feedback system and to estimate the level of LH in the hypothalamic milieu, the concentrations of LH in the peripheral circulation, portal circulation, and third ventricle were measured during an estradiol-induced preovulatory LH surge (n = 4). Neither the bolus nor continuous administration of LH into the third ventricle had any effect on the mean interpulse interval, nadir, pulse amplitude, or circulating level of systemic LH. Furthermore, despite portal LH concentrations being more than 20-fold higher than jugular LH concentrations, LH levels in third ventricular cerebrospinal fluid remained barely detectable and did not reflect dynamic secretory events in the peripheral or hypothalamo-hypophyseal portal blood. These data demonstrate that in ewes, little pituitary LH reaches the third ventricle, and the small amount that does is unable to affect peripheral gonadotropin release. Our study suggests, therefore, that a short loop feedback system for LH does not exist in the ewe.  相似文献   

17.
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19.
To estimate the incidence of low growth hormone (GH) concentration in children and adolescents with idiopathic short stature, overnight GH levels were measured in 167 subjects. The results were compared with data from 132 normal children of similar pubertal stage, bone age, or body mass index. The majority of short children had normal overnight GH concentrations in a distribution not significantly different from that observed in normal children. However, in 6% of children grouped by pubertal stage and in 13% of children grouped by bone age, overnight GH levels were below the 95% confidence limits of normal. The overnight GH levels were above normal in 6%. The observed frequencies of both low and high GH levels were significantly greater than expected (P < 0.001). However, when body mass index was included in the analysis, only 5% of the children had low GH measures, and only 4% had high GH measures (both not significant). This frequency of low overnight GH levels in short children is considerably less than that reported by others. Thus, these data do not support the hypothesis that a deficiency of spontaneous GH secretion is a common cause of short stature. We conclude that standard GH stimulation tests, despite their limitations, remain the best definitive test of GH secretion. Subsequent overnight GH studies may be useful, however, in selected clinical settings such as previous cranial irradiation or other central nervous system disorder.  相似文献   

20.
One copper-silver ionization system was sequentially installed onto the hot-water recirculation lines of two hospital buildings colonized with Legionella pneumophila, serogroup 1. A third building with the same water supply and also colonized with Legionella served as a control. Four weeks after activation of the system, distal site positivity for Legionella in the first test building dropped to zero. After operating for 16 weeks, the system was disconnected and installed onto the second test building. Twelve weeks of disinfection reduced the distal site positivity for Legionella in the second test building to zero. Legionella recolonization did not occur in the first test building for 6-12 weeks and in the second test building for 8-12 weeks after inactivation of the system. The control building remained Legionella-positive throughout the experimental period. A significantly higher copper concentration was found in the biofilm taken from a sampling device than in that from water. This is likely to be the reason that the copper-silver ionization system had the residual effect of preventing early recolonization. Our study raises the possibility that one copper-silver unit could be rotated among several buildings to maintain a Legionella-free environment. Such an approach may be cost-effective for buildings housing individuals at low risk for contracting legionnaires' disease.  相似文献   

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