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Biomedical subjects

M Genel

Publications and source records attributed to M Genel.

At least 55 records · Page 3Linked to original sources
PubMed1984

The effect of small but sustained elevations in circulating growth hormone on fuel metabolism in growth hormone deficiency.

Although growth hormone (GH) concentrations are not always pathologically elevated in patients with acromegaly, it has been suggested that the metabolic and somatic consequences of this condition may be due to a loss of the normal episodic secretion of GH. To examine the effects of maintaining modest but constant levels of circulating GH, we administered continuous subcutaneous infusions of growth hormone (CSIGH) to eight previously untreated GH-deficient children (6-19 yr). CSIGH given for 90 h in doses equivalent to the standard dose for replacement therapy, raised mean serum GH levels from less than 3.0 to 5.9 +/- 1.0 ng/ml. In comparison, 24-h mean GH levels in five normal adolescents averaged 10.1 +/- 1.5 ng/ml. As expected, however, normals showed much more variability in GH concentration. The constant elevations in serum GH levels achieved with CSIGH produced significant impairment of oral glucose tolerance. During CSIGH, plasma glucose concentrations 60-120 min after oral glucose loading were 30-40 mg/dl higher than corresponding pre-infusion values (P less than 0.01). This impairment of oral glucose tolerance during CSIGH occurred despite a doubling of the area under the insulin/time curve after oral glucose (P less than 0.02 versus pre-infusion area). Indeed, plasma insulin levels after oral glucose in patients on CSIGH exceeded those observed in normal controls, suggesting that CSIGH had induced a degree of insulin resistance. There was a transient increase in plasma free fatty acid levels on the first day of CSIGH. Somatomedin-C concentration remained unchanged in four of six patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Acromegaly↗
PubMed1982

Presence of H-Y antigen in patients with Ullrich-Turner syndrome and X-chromosome rearrangements.

Cells from eight of ten patients with gonadal dysgenesis and an isochromosome for the long arm of X, (i(Xq)), have been found to be H-Y antigen-positive, using an assay that employs rat antiserum and Raji cells. In addition, two patients with del(Xq) were also found to be H-Y antigen-positive, whereas four patients in whom only a 45,X line was detected were H-Y antigen-negative. These findings suggest that the X chromosome plays a role in the expression of H-Y antigen in the absence of a Y chromosome. Since our patients with i(Xq) show no evidence of testicular differentiation, it is clear that there is not enough H-Y antigen on these patients' cells to direct the development of a testis. These findings are consistent with the view that the normal functioning of genes on the X and the Y chromosomes is necessary for testicular organogenesis to occur.

Chromosome Deletion↗
PubMed1982

Effect of intensive insulin treatment on linear growth in the young diabetic patient.

Although impaired growth is a well-recognized complication of uncontrolled diabetes, it has not been established whether less severe metabolic derangements commonly seen with conventional treatment adversely affected growth potential. To examine this question, growth velocity was measured in nine type 1 diabetic patients (age 14 +/- 3 years) before and after six months of intensive insulin treatment either with the insulin pump or with multiple injections, which lowered mean plasma glucose concentration from 270 +/- 96 to 105 +/- 55 mg/dl and total glycosylated hemoglobin from 12.4 +/- 3.0 to 8.4 +/- 1.5% (mean +/- SD). During conventional treatment, growth velocity (5.3 +/- 2.2 cm/year) was within the range of normal despite elevations in plasma glucose concentrations. However, growth velocity increased sharply during intensive treatment (to 9.4 +/- 3.9 cm/year, P less than 0.005), reaching values in excess of normal in seven patients. The increase in growth velocity observed during intensive treatment was associated with a twofold rise in plasma somatomedin-C values. Skeletal maturation, previously normal or slightly delayed, did not advance excessively. These data indicate that the metabolic changes accompanying intensive treatment may enhance growth in diabetic children, even in those with apparently normal growth velocity during conventional therapy.

Adolescent↗
PubMed1982

Influence of long-term insulin infusion pump treatment of type I diabetes on diabetic retinopathy.

Isolated case reports have suggested short-term beneficial effects of subcutaneous insulin infusion pump treatment on background and proliferative diabetic retinopathy. To evaluate this question further, 30 eyes of 15 Type I diabetic patients were evaluated prospectively before and after 11--23 months (mean 18.1 months) of pump treatment. In each patient plasma glucose and total glycosylated hemoglobin fell to normal or near normal levels. The ten eyes without diabetic retinopathy at entry remained without. Four of 20 eyes with diabetic retinopathy at entry advanced by modified Early Treatment Diabetic Retinopathy Study (ETDRS) classification, including one eye that progressed from background to proliferative diabetic retinopathy. No eyes with diabetic retinopathy improved their modified ETDRS classification. One eye progressed to blindness; no other eye lost vision. Six eyes had laser treatment prior to insulin pump treatment; four of these and two more required laser during pump treatment. Two eyes had vitreous hemorrhages prior to pump treatment; one of these and four others hemorrhaged during pump treatment. No eyes with diabetic retinopathy showed regression of microvascular changes. The data suggest prolonged restoration of near normal glucose metabolism with the insulin pump does not reverse established diabetic retinopathy. Whether pump treatment slows the progression, or prevents the development, of diabetic retinopathy remains to be established.

Adolescent↗
PubMed1982

Catecholamine-thyroid hormone interactions: II. Thyroid hormone and platelet MAO activity in patients with thyroid disorders.

Platelet monoamine oxidase (MAO) activity and serum thyroxine indices were determined in 62 children and adolescents currently undergoing medical treatment for various thyroid disorders. The platelet MAO activity of these patients was similar to that of control and contrast groups previously reported, and there were no differences when patients were grouped according to specific thyroid disorders. Estimated free thyroxine and total thyroxine levels were generally in the upper normal or slightly elevated range and were not significantly related to MAO activity.

Adolescent↗
PubMed1982

Cognitive and emotional functioning in hypopituitary short-statured children.

Eleven children with documented growth hormone deficiency were studied to assess their cognitive and emotional functioning and their academic achievement before and after 1 year of human growth hormone replacement therapy. Standardized personality and intelligence measures were used, and records of school achievement, as well as developmental and family history from parents, were obtained. Although some subjects in this group were coping with problems other than their short stature (e.g., other medical and psychosocial problems), their intelligence and academic achievement were found to be positively correlated with socioeconomic status and independent of the condition of hypopituitarism. This study supports others that have found these children vulnerable to problems of emotional adjustment in middle and late childhood. Because of the heterogeneity of the group, findings must be interpreted cautiously. However, the consistent finding of disturbance in visual-motor integration is thought to be significant and demonstrates the need for further research that will examine possible neurological sequelae of long-term growth hormone deficiency.

Adaptation, Psychological↗
PubMed1981

Insulin-infusion-pump treatment of diabetes: influence of improved metabolic control on plasma somatomedin levels.

We examined whether changes in somatomedin accompany those seen in glucose and growth hormone during treatment with the insulin-infusion pump. somatomedin levels in eight insulin-dependent diabetics (13 to 29 years of age) were measured before and after 16 weeks of outpatient insulin-pump treatment, which lowered mean glucose from 245 +/- 21 to 100 +/- 5 mg per deciliter and total glycosylated hemoglobin from 16.2 +/- 1.2 to 9.7 +/- 0.3 per cent (mean +/- S.E.M.). During conventional insulin therapy, both total somatomedin and somatomedin C were within the normal range, despite elevations in growth hormone. Pump treatment resulted in a 70 to 75 per cent increase in both total somatomedin and somatomedin C (P less than 0.05) and a fall in growth-hormone concentrations. In the two growing adolescents, growth velocity doubled during 13 to 15 months of pump treatment. Our data suggest that the improved insulin delivery or metabolic control increases somatomedin levels despite a decrease in growth hormone. Thus, insulin-pump treatment may be useful in optimizing growth in diabetic children.

Adolescent↗
PubMed1981

H-Y antigen negative patients with testicular tissue and 46,XY karyotype.

H-Y antigen could not be detected on lymphocytes from two male pseudohermaphrodites with 46,XY karyotypes and testicular tissue. One of the patients had additional assays performed on fibroblasts grown from the skin, and the gonadal ridge--these were also negative. The H-Y antiserum was raised in rats, with Raji cells the target of cytotoxicity tests. In these patients. the substance that promoted testicular differentiation does not have serologic H-Y antigen detectable by the assay used. It appears that H-Y antigen that is commonly measured in neutralization reactions may not be the only form of testicular organizing factor present.

Adolescent↗
PubMed1981

Juvenile rheumatoid arthritis in children with diabetes mellitus.

Seven children with insulin-dependent diabetes mellitus were found to have juvenile rheumatoid arthritis; six of these children had the polyarticular form of the disease. All six had positive serology (rheumatoid factor and/or antinuclear antibody) and clinical or serologic evidence of autoimmune diseases usually ascribed to the thyrogastric cluster. Five expressed HLA antigens associated with increased risk for both diabetes and rheumatoid arthritis in adults. Evidence of B cell hyperactivity and impaired T cell response was found in some, but immunoregulatory function was normal in all. The association of these two diseases may be the result of factors other than chance alone, and may be more common than previously suspected.

Adolescent↗
PubMed1981

Ultrasound examination of pubertal girls and of patients with gonadal dysgenesis.

Girls with hypogonadism caused by hypothalamic lesions or chromosomal abnormalities need accurate pelvic exams to delinate pelvic structures. This work presents an evaluation of the usefulness of ultrasound examination of the pelvis in females with aberrant sexual development. Girls with these problems often need multiple pelvic examinations to monitor their uterine response to hormone therapy. Thirty-two patients with a variety of abnormalities including Mullerian agenesis and hypothalamic hypogonadism as well as patients with abnormal karyotype commonly associated with gonadal dysgenesis and male pseudohermaphrodism were studied. Repeat ultrasound scans were performed to quantitate uterine response to therapy. Ovarian visualization was usually possible, even in prepuberal girls. Following some patients at risk for gonadal tumors may be possible using repeat ultrasound examinations. The cooperation of the patients as well as of their families was gratifying, and the girls appeared to be more relaxed during ultrasound examination than during a pelvic examination.

Adolescent↗
PubMed1981

Hereditary ectodermal dysplasia, olivopontocerebellar degeneration, short stature, and hypogonadism.

Two teenaged children born of normal parents in a consanguineous family had evidence of abnormal neurological, endocrine, and ectodermal development. They had mental retardation, hearing loss, ocular dysmetria, hyperreflexia, and ataxia consistent with olivopontocerebellar degeneration. They had hypogonadotrophic hypogonadism and extremely short stature despite normal serum growth hormone and somatomedin-C. There was also hypodontia with peg shaped teeth and mid-face hypoplasia. This syndrome of hypoplasia of mid-lind structures appeared to be inherited as an autosomal recessive trait.

Adolescent↗
PubMed1981

Efficacy of the insulin pump in the home treatment of pregnant diabetics.

The efficacy and feasibility of the insulin infusion pump in pregnancy were examined in seven class D to FR diabetics, maintained on the pump at home from 10 to 29 wk gestation until delivery. An improvement in glucose control was achieved within the first month and sustained to term. Home monitoring demonstrated a fall in mean blood glucose levels from 135 mg/dl range 98-175, prepump) to 104 mg/dl (range 84-120) and a 25-30% reduction in standard deviations during pump treatment. Furthermore, glycosylated hemoglobin levels were normalized in each patient. During periodic inpatient evaluations, mean 24-h plasma glucose levels were slightly, but not significantly, lower after pump treatment (97 vs 86 mg/dl). However, glycemic excursions were strikingly diminished; MAGE values and standard deviations fell by 45% and 34%, respectively. The total daily insulin dose required at the start of pump treatment was 31% less than the conventional dose used before the pump (P less than 0.002). Thereafter the insulin dose increased by approximately 2.5 U/wk, with the basal infusion remaining at 40% of the total dose throughout the pregnancy. All infants were born at term, had no macrosomia or neonatal problems, and had normal intravenous glucose tolerance tests at 2 h of age. We conclude that the insulin infusion pump, managed at home, is a highly efficient way to achieve normal or near-normal glucose levels in the pregnant diabetic.

Adult↗
PubMed1980

H-Y antigen in X,i(Xq) gonadal dysgenesis: evidence of X-linked genes in testicular differentiation.

Three years ago, we detected H-Y antigen in the white blood cells of a phenotypic female with several of the stigmata of Turner's syndrome, and the mosaic karyotype: 45,X/46,X,i(Xq). We surmised at the time that the isochromosome, i(Xq), may have contained occult Y-Chromosome-derived material. We have now confirmed the presence of H-Y in this patient and we have obtained evidence for the presence of H-Y in four of five other similar patients, all of whom are notable for carrying at least a single cell line with the karyotype 46,Xi(Xq). Although we cannot categorically exclude the presence of Y-chromosomal genes in the cells of these patients, there is no cytogenetic evidence of structural rearrangement involving the Y in any of the cases. Expression of H-Y structural genes are X-situated, or alternatively that they are autosomal and X-regulated. It would follow that the H-Y+ cellular phenotype per se is not a valid marker for the Y-chromosome, and that H-Y genes that have been mapped to the pericentric region of the Y may be regulatory.

Adolescent↗
PubMed1980

Outpatient treatment of juvenile-onset diabetes with a preprogrammed portable subcutaneous insulin infusion system.

Seven patients with juvenile-onset, insulin-dependent diabetes (aged 13 to 32 years) were continuously treated for 12 to 32 weeks while out of the hospital in their usual environment with a portable, battery-powered infusion pump which delivers insulin subcutaneously in basal (between-meal) doses with pulse dose increments before meals. Mean blood glucose levels (237 +/- 28 mg/dl during conventional insulin therapy) fell to 105 +/- 5 mg/dl after four weeks of pump treatment (p less than 0.01) and were maintained at 80 to 104 mg/dl as pump treatment was continued beyond eight weeks. Glycosylated hemoglobin levels (16.0 +/- 1.5 per cent before pump therapy) also fell within two weeks (p less than 0.01) reaching normal values (9.9 +/- 0.3) after eight weeks of pump therapy. Mean plasma cholesterol and triglyceride levels were elevated during conventional therapy and fell to normal after pump treatment. After the first month of pump treatment, only minor adjustments in insulin dose (less than 5 per cent of total daily dose) were made. No episode of mechanical pump failure occurred during the 1,110 patient-days of treatment. Overinsulinization and underinsulinization due to human error were relatively rare (four and six episodes, respectively) and failed to result in symptoms of hypo- or hyperglycemia. All patients performed their usual home, work or school activities during pump treatment. We conclude that normalization or near normalization of blood glucose levels can be achieved with a portable subcutaneous insulin infusion system when continuously used to treat patients with juvenile-onset, insulin-dependent diabetes outside the hospital for three to eight months.

Adolescent↗
PubMed1980

XY gonadal dysgenesis associated with the congenital nephrotic syndrome.

The occurrence of a nephrotic syndrome in a female infant with a 46,XY karyotype is reported. The internal genitalia were female but a microscopic region of immature testicular tissue was present in 1 of 2 streak gonads. The relationship of this child's abnormal genital differentiation to her renal disease is discussed in the light of reported cases of infantile nephritis and Wilms' tumor in male pseudohermaphrodites. It is suggested that a common teratogen operating on the embryonic urogenital ridge may cause both genital and renal anomalies.

Female↗