Effects of growth hormone treatment in adults with Prader-Willi syndrome.

OBJECTIVE: Since limited data exist on adults with Prader-Willi syndrome (PWS) and growth hormone (GH) treatment, we report our experience on the effects of treatment for one year on body composition, physical activity, strength and energy expenditure, diet, general chemistry and endocrine data with quality of life measures. DESIGN: We studied 11 adults with PWS (6F:5M; average age=32 yrs) over a 2 year period with GH treatment during the first year only. Electrolytes, IGF-I, glucose, thyroid, insulin, lipids, body composition, physical activity and strength, diet, energy expenditure and quality of life data were collected and analyzed statistically using linear modeling at baseline, at 12 months following GH therapy and at 24 months after treatment cessation for 12 months. RESULTS: Total lean muscle mass was significantly increased (p<0.05) during GH treatment along with moderate-vigorous physical activity and plasma IGF-I and HDL levels, but returned to near baseline after treatment. Percent body fat decreased during the 12 months of GH treatment but increased after treatment. CONCLUSIONS: Previously reported beneficial effects of GH treatment in children with PWS were found in our adults regarding body composition, physical activity and plasma HDL and IGF-I levels. Several beneficial effects diminished to near baseline after cessation of GH treatment for 12 months supporting the continuation of treatment in PWS into adulthood and possibly adults not previously treated during childhood.

Small rat islets are superior to large islets in in vitro function and in transplantation outcomes.

Barriers to the use of islet transplantation as a practical treatment for diabetes include the limited number of available donor pancreata. This project was designed to determine whether the size of the islet could influence the success rate of islet transplantations in rats. Islets from adult rats were divided into two groups containing small (diameter <125 microm) or large (diameter >150 microm) islets. An average pancreas yielded three times more small islets than large. Smaller islets were approximately 20% more viable, with large islets containing a scattered pattern of necrotic and apoptotic cells or central core cell death. Small islets in culture consumed twice as much oxygen as large islets when normalized for the same islet equivalents. In static incubation, small islets released three times more insulin under basal conditions than did large islets. During exposure to high glucose conditions, the small islets released four times more insulin than the same islet equivalencies of large islets, and five times more insulin was released by the small islets in response to glucose and depolarization with K+. Most importantly, the small islets were far superior to large islets when transplanted into diabetic animals. When marginal islet equivalencies were used for renal subcapsular transplantation, large islets failed to produce euglycemia in any recipient rats, whereas small islets were successful 80% of the time. The results indicate that small islets are superior to large islets in in vitro testing and for transplantation into the kidney capsule of diabetic rats.

CD40/154 blockade and rejection of islet allografts in the streptozotocin and autoimmune diabetic rat.

Islet transplantation in children with autoimmune diabetes will require immunosuppression that has minimal toxicity and side-effects, and overcomes the barrier of autoimmunity. Since antibodies directed against the CD40/154 co-stimulatory pathway may meet these criteria, we have tested the ability of hamster antirat CD154 (AH.F5, Biogen) to prevent rejection of renal subcapsular islet allografts in streptozotocin (STZ) or autoimmune (AUTO) diabetic diabetes-resistant biobreeding (DRBB) rats. STZ diabetic rats that received anti-CD154 at 15 mg/kg per dose but not 10 mg/kg per dose did not have evidence of rejection until about 80-120 d post-transplantation, by which time antibody concentrations had returned to undetectable levels. Rats retreated with anti-CD154 before recurrence of diabetes had a prolonged period of disease-free survival. Most of these rats had recurrence following a spleen cell challenge. In contrast, AUTO diabetic DRBB rats treated with anti-CD154 had recurrence of diabetes between 7 and 12 d following transplantation of the Dark Agouti (DA) islets. In a separate set, AUTO diabetic rats that received a simultaneous islet isograft, islet allograft and thyroid allograft had focal accumulation of lymphocytes at the periphery of the isograft, while the islet and thyroid allografts had diffuse infiltration with lymphocytes and destruction of tissue with no residual staining for glucagon. Therefore, autoimmunity adds an additional barrier to islet allotransplantation that is not overcome with CD40/154 blockade in an animal model that closely parallels autoimmune diabetes in humans. The results indicate the importance of testing regimen of islet transplantation in animal models of autoimmune diabetes.

Anti-CD154 (CD40L) prevents recurrence of diabetes in islet isografts in the DR-BB rat.

Islet transplantation for the treatment of autoimmune diabetes is more difficult because of the additional barrier presented by the autoimmunity. We tested the ability of hamster anti-rat CD154 to prevent recurrence of diabetes in renal subcapsular islet isografts in DR-BB (RT1uu) rats with established autoimmune diabetes. Experimental animals with established diabetes received intravenous injections of 15 mg/kg anti-CD154 on a specified schedule starting 2 days before renal subcapsular transplantation of an islet isograft. Control animals received either saline or hamster IgG. Plasma glucose levels >250 mg/dl over 3 days were used to indicate the recurrence of diabetes. Rats that received saline (n = 5) or control antibody (n = 3) had a recurrence of diabetes 6-11 days after transplantation. Histological examination of islet isografts from these rats showed complete destruction of the insulin-producing portion of the isograft with residual cells positive for glucagon. Recipient rats that received anti-CD154 at the 15-mg/kg dosage (n = 6) did not have a recurrence of diabetes for 308-461 days after transplantation. Islet isografts removed from the rats showed low levels of insulin immunoreactivity, high levels of insulin mRNA, and focal infiltration with lymphocytes but no evidence of islet destruction. Mean peak antibody concentration was 266 microg/ml and returned to undetectable levels by 67-88 days after transplantation. Rats that received anti-CD154 starting at 4-7 days after transplantation had a recurrence of diabetes within 11 days of the isotransplantation. Therefore, anti-CD154 as the sole immunomodulator prevented the recurrence of diabetes in islet isografts in rats with established autoimmune diabetes. This suggests that CD40/CD154 blockade is effective in preventing the insulitis or the effector phase of autoimmune diabetes.

Growth during and after a trial of growth hormone releasing hormone 1-29 in children with idiopathic short stature or growth hormone neurosecretory dysfunction.

The growth promoting effects of once nightly subcutaneous injections of growth hormone releasing hormone (GHRH) 1-29 (30 microg/kg) for 6 months were studied in 16 slowly growing prepubertal children with idiopathic short stature (ISS; Group 1) and 8 similar children with growth hormone neurosecretory dysfunction (GHND; Group 2). Each child underwent endogenous growth hormone evaluation using both pharmacological and physiological testing; each had stimulated values > 10 microg/l and were subsequently placed into one of two groups based on pooled 12-hour overnight GH of < or > or = 3 microg/l. Each patient was followed every three months for one year. There were no significant differences in the two groups throughout the study with the exception of the endogenous GH levels. Both groups responded to GHRH therapy with similar significant increases in their rates of growth. Although a subset of patients (6 of 21) continued to grow at a rate significantly greater than the pre-therapy rate of growth, overall rates of growth were not significantly different from the pre-therapy growth rates 6 months following the discontinuation of GHRH treatment. We conclude that GHRH 1-29, given in the doses provided, leads to similar changes in growth rates in short, slowly growing children who are GH sufficient and those with GHND. Despite prior reports to the contrary, GHND patients do not experience a sustained increased in growth rate upon discontinuation of GHRH.

Growth hormone therapy of Turner's syndrome: beneficial effect on adult height.

OBJECTIVE: To carry out a multicenter, prospective, randomized trial of human growth hormone (GH), alone or in combination with oxandrolone (OX), in patients with Turner's syndrome (TS). METHODS: In an initial phase lasting 12 to 24 months, 70 girls with TS, verified by karyotype, were randomly assigned to one of four groups: (1) observation, (2) OX, (3) GH, or (4) GH plus OX. After completion of the first phase, group 3 subjects continued to receive GH only. All other subjects were treated with GH plus OX. Subjects were followed up until attainment of adult height and/or cessation of treatment. Data from this trial were compared with growth characteristics of 25 American historical subjects with TS (matched for age, height, parental target height, and karyotype) who never received either GH or androgens. RESULTS: Of the 70 subjects enrolled, 60 completed the clinical trial. The 17 subjects receiving GH alone all completed the trial and reached a height of 150.4+/-5.5 cm (mean +/- SD), 8.4+/-4.5 cm taller than their mean projected adult height at enrollment (95% confidence interval [CI]: 6.3 to 10.6 cm). The 43 subjects receiving GH plus OX attained a mean height of 152.1+/-5.9 cm, 10.3+/-4.7 cm taller than their mean projected adult height (95% CI: 8.9 to 11.7 cm). The historical control subjects had a mean adult height of 144.2+/-6.0 cm, precisely matching their original projected adult height of 144.2+/-6.1 cm. CONCLUSIONS: GH, either alone or in combination with OX, is capable of stimulating short-term growth and augmenting adult height in girls with TS. With early diagnosis and initiation of treatment, an adult height of more than 150 cm is a reasonable goal for most girls with TS.

Prevalence of hypertension in patients with type II diabetes in referral versus primary care clinics.

We compared the prevalence of hypertension in patients with non-insulin-dependent diabetes mellitus (NIDDM) in referral and primary care practices using definitions of The Fifth Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC-V), while controlling for other risk factors such as hypertension, obesity, smoking, and age. Patients (n = 1443) were enrolled consecutively from a large referral practice at the Jackson Diabetes Center and four primary care clinics in the vicinity. Blood pressures were measured at three clinic visits after a 5-min rest in a sitting position using a standard clinical sphygmomanometer. Charts were reviewed to determine diabetes duration, insulin usage, height, weight, smoking history, use of antihypertensive and oral hypoglycemic medications, socioeconomic status, and race. Patients were classified as hypertensive based on JNC-V definitions or if they were on antihypertensive medication. Hypertension was termed uncontrolled if blood pressure was JNC-V Stage 2 or higher while on antihypertensive medication. Seventy-eight percent of referral clinic and 55% of primary care clinic patients had either JNC-V State 1 or higher hypertension or were on antihypertensive medication. Actual blood pressures indicated that more patients had JNC-V Stage 1 (mild) or higher hypertension in referral compared to primary care clinics (62% versus 48% p = 0.01) but fewer had JNC-V Stage 2 or higher (moderate-severe) hypertension (12% versus 19% p = 0.002). Patients seen in the referral clinic were significantly more likely to have greater age, greater duration of diabetes, higher insulin dosage, longer smoking history, antihypertensive medication, and live outside the metropolitan area. By logistic regression, the odds of hypertension were significantly increased with age (OR 1.51/decade), BMI greater than 27 (OR 2.17), diabetes duration (OR 1.04/year), and insulin dosage (OR 1.74/U/kg). Current smoking and attending a referral clinic were not significantly related. The odds of moderate-severe hypertension were significantly increased with age (OR 1.23/ decade), decreased by attending a referral clinic (OR 0.45), and not significantly related to other confounders in the model. The prevalence of hypertension among patients with NIDDM was higher in referral than primary care clinics. The higher prevalence in the referral practice can be accounted for by the greater severity of associated risk factors in the referral practice patients; however, most patients will be diagnosed and treated for hypertension prior to referral. More patients in the referral practice were on hypertensive medication, which lowered the stage or severity of hypertension but still not to the normal range. The results suggest that the primary detection of hypertension in patients with type II diabetes resides with the primary care physician. Management of hypertension will require both a delineation and acceptance of responsibilities between the primary care physician and diabetes specialists.

Synthetic strategies for the preparation of precursor polymers and of microcapsules suitable for cellular entrapment by polyelectrolyte complexation of those polymers.

The production of microcapsules suitable for the entrapment of mammalian cell by means of polyelectrolyte complexation has, of a necessity, led to the development of novel strategies for the preparation of relatively bioinert polymers which complex efficiently under unique conditions to produce a mechanically resilient membrane with efficient transport properties. In this communication we relate a brief overview of capsule-membrane forming systems for the immunoisolation (or potential immunoisolation) of mammalian cells, which are based upon the complexation of polyelectrolyte (PE) polymers; with emphasis on precursor synthesis and relationships between precursor polymer structure and capsule membrane stability.

Psychosocial adjustment and the role of functional status for children with asthma.

This study examined the psychosocial adjustment of children with asthma compared to children with diabetes, with cancer, and healthy children and the role of functional status in psychosocial adjustment. The total sample included 100 children, aged 8-16 years, (mean = 11.5 years), consisting of 48 boys and 52 girls. Children with asthma scored significantly higher on measures of affective adjustment (depression and internalizing behavior), significantly lower on self-esteem, and evidenced significantly greater functional impairment. Children with cancer missed significantly more school days. After controlling for functional status, no significant differences remained in affective adjustment but absences remained significantly higher for the children with cancer.

Failure of nonimmunogenic islet allografts to induce donor-specific immunological unresponsiveness [corrected].

Highly purified perinatal rat islets, isolated by a nonenzymic in vitro culture technique, have been successfully transplanted across complete MHC barriers without immunosuppression. Acceptance of these allogeneically transplanted islets is hypothesized to result from an absence of antigen presenting cells (APCs) within the islets. This study was designed to examine the effects of organ transplantation and cyclosporine (CsA) therapy on the development of immunological unresponsiveness in recipients receiving a graft of culture-isolated islets. Kidneys were successfully allotransplanted into unilaterally nephrectomized rats, across a complete MHC barrier (Rt1lv1 to Rt1u) using CsA therapy initiated on the day of transplantation (7.5 mg/kg, orally for 14 days). Remaining native kidneys were removed 14 days following renal allotransplantation. Limited mononuclear cell (MNC) infiltrates were observed in biopsies of renal allografts, taken 30 days posttransplant, but failure of the renal allograft was not observed. Animals bearing established renal allografts (n = 10) received allografts of approximately 200 highly purified perinatal islets (ACl, n = 5; F-344, n = 5), transplanted to the kidney subcapsule of the established renal allograft at least 30 days following renal allotransplantation (at least 16 days following termination of CsA). Islet allografts were not rejected, and, as expected, did not initiate rejection of the renal allograft. Similar results were observed in renal allograft recipients rendered diabetic by a single injection of streptozotocin (STZ, 65 mg/kg, n = 5) and receiving islet allografts of sufficient mass (approximately 1200-1400 islets) to reverse STZ-induced hyperglycemia. Further, neither islet nor renal allografts were rejected following challenge by 1 x 10(7) donor-strain dendritic cells (DCs).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical diagnoses of children with extremely short stature and their response to growth hormone.

This study was undertaken to determine the prevalence of clinical diagnoses in a group of children with extremely short stature (standard deviation score for height, < -2.5) and to determine whether the classification might help in predicting response to human growth hormone (hGH) treatment. We classified 49 children referred consecutively to our outpatient clinic for evaluation of short stature with heights < -2.5 standard deviation score and bone ages < 9 years for girls or < 10 years for boys (to avoid an effect of puberty on the response to hGH). The diagnostic categories were growth hormone (GH) deficiency, constitutional delay, familial short stature, and primordial short stature. After referral, Turner syndrome was diagnosed in two children. The remaining 47 children were classified according to primary criteria, considered essential for the diagnosis, and secondary criteria, considered necessary but of lesser importance. There were five children, four children, no children, and one child classified, respectively, with GH deficiency, constitutional delay, familial short stature, and primordial short stature by using the most rigorous definitions of the diagnoses. There was significant overlap in the diagnoses other than GH deficiency. Growth hormone deficiency defined by the primary criterion of peak stimulated GH values < 5 micrograms/L was the most definitive. Of the 47 children, 7 were classified as GH deficient by this criterion and 5 were classified as GH deficient by the primary and secondary criteria. The mean pretreatment growth rate (3.1 +/- 1.9 cm/yr) of the group with stimulated GH values < 5 micrograms/L was significantly less than that in the other groups (4.2 +/- 1.5 cm/yr). The mean growth rate of the children with GH deficiency during treatment with hGH was greater than that in the other groups and was 3.4 times greater than the pretreatment growth rate. The mean growth rate of children in the other groups during hGH treatment was twofold greater than the pretreatment growth rate. We conclude that except for GH deficiency, children with an extreme degree of short stature are not easily classified by standard diagnostic criteria, and that most short children have a positive response to hGH therapy regardless of the diagnosis; therefore a specific clinical diagnosis should not be used to exclude children from hGH therapy.

Ambulatory blood pressure in type I diabetes mellitus. Comparison to presence of incipient nephropathy in adolescents and young adults.

AMBP measurements were obtained at 20-min intervals during the day and at 60-min intervals during the night in 38 adolescents and young adults (12-25 yr old) with type I diabetes, and in 36 healthy, nondiabetic control subjects of comparable age. The group of patients with elevated AER (greater than 15 micrograms/min) had higher mean 24-h sBP, dBP, and BPB (defined as the prevalence of systolic readings greater than 130 mm Hg or diastolic readings greater than 85 mm Hg) compared with both the group of patients with type I diabetes and AER less than 15, and the control group. The normal diurnal variation in BP and BPB was observed in the control group and the group with type I diabetes and AER less than 15, whereas the nocturnal decrease observed in the group with type I diabetes and AER greater than 15 was not statistically significant. Elevations in AMBP of the patient group with AER greater than 15 were reflected in random BP measurements. Even though the mean random BP measurements of all groups were within the normal range for age, the mean random sBP and dBP of the type I diabetes patients with AER greater than 15 was higher than both the control group and the group with type I diabetes and AER less than 15. The GFR, determined by the clearance of 99Tc-DTPA, was associated negatively with measures of AMBP and AER in the group with AER greater than 15.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased islet allograft survival after extended culture by a mechanism other than depletion of donor APCs. Lack of correlation between the elimination of donor MHC class II-positive accessory cells and increased transplantability.

Neonatal rat islets derived by nonenzymic (in vitro) isolation procedures from the Fischer-344 (F-344, Rt1lv1) strain have been shown to be freely transplantable across complete MHC barriers without the use of any form of immunosuppression. However, islets obtained by in vitro isolation from some donor strains, such as the ACI, retain a degree of immunogenicity upon transplantation. This study examined the immunogenic nature of these neonatal ACI islets, and correlated this with the presence of a residual population of MHC class II-positive antigen presenting cells within the islets. In addition, further reduction of immunogenicity of isolated neonatal ACI islets by extension of the culture period was examined. Islets were obtained from neonatal ACI donors by culture-isolation and placed in secondary culture for either 2 days (10 day total culture period, standard culture) or 42 days (50 day total culture period, extended culture). Standard-culture ACI islets were rejected 33% to 100% of the time in five different recipient strains (depending on recipient strain). Compared with control grafts of fresh pancreatic fragments, rejection rates were significantly lower in two strain combinations (ACI to BUF, P = 0.044 and ACI to F-344, P = 0.028), and for all recipient strains combined (P less than 0.001). Extended-culture ACI islets survived significantly longer in all five recipient strains tested (ACI to BN, P = 0.024; ACI to BUF, P = 0.005; ACI to LEW, P = 0.004; ACI to F-344, P = 0.008 and ACI to WF, P = 0.024) and for all strains combined (P less than 0.001). No MHC class II-positive cells were detected upon examination of sectioned neonatal ACI islets using peroxidase immunocytochemistry (OX-6 antigen) in either the standard-culture or extended-culture groups. These results suggest that the increased survival of grafts of extended culture ACI islets is due to a mechanism other than the elimination of class II-positive APCs from the islets. Although possible down-regulation of MHC class II expression on residual APCs during the culture process may make identification of these cells difficult, alternative mechanisms such as the down-regulation of MHC class I antigen, resulting in the reduction of available donor target, or the existence of an accessory cell that is not constitutively MHC class II-positive, may be responsible for this increased graft survival.

Long-term treatment with growth hormone of children with short stature and normal growth hormone secretion.

Children with short stature but normal growth rate and/or normal growth hormone response to sleep and secretagogues were treated with recombinant methionyl human growth hormone, 0.3 mg/kg per week. In each year of treatment, about 80% of the subjects maintained an increase in growth rate greater than the defined limit (greater than 1 cm/yr above pretreatment growth rate) for continuation of human growth hormone treatment. Comparison of the group that continued to respond to human growth hormone with the group that did not maintain an accelerated growth rate did not reveal differences in bone age delay, sleep or secretagogue-stimulated human growth hormone secretion, degree of short stature either absolute or relative to target height, and somatomedin C concentration before or after initiation of therapy. The group that failed to respond to the human growth hormone treatment in the first year of treatment was younger and had a higher pretreatment growth rate. Review of the longitudinal growth curves revealed five patterns of response to human growth hormone treatment: (1) failure to increase growth rate in two subjects with height SD scores within 1 SD of target height, (2) failure to increase growth rate in five subjects with height SD scores greater than 1 SD less than the target height, (3) acceleration in growth rate in three subjects that was not maintained until achievement of a height within 1 SD of the target height, (4) acceleration of growth rate in five subjects that was maintained until achievement of a height within 1 SD of the target height, and (5) acceleration in growth rate that was maintained during the 3 years of treatment in 15 subjects who had not attained a height within 1 SD of the target height. We conclude that human growth hormone treatment of some but not all short children with "normal" growth hormone secretion will result in sustained acceleration of growth rate and attainment of prepubertal heights that are closer to but do not exceed their genetic height potential. A clinical trial of human growth hormone may be necessary to determine which subjects will benefit from the treatment.

The role of disease duration and hypertension in albumin excretion of type I diabetes mellitus.

The objective of this study was to examine the relationship between blood pressure, albumin excretion, and renal function in patients with type I diabetes mellitus. The study design was as follows: nonselected consecutive patients with type I diabetes mellitus were divided into three groups by level of albumin excretion rate (AER): less than 20 micrograms/min, 20 to 200 micrograms/min, and greater than 200 micrograms/min. The setting for the study was an outpatient diabetic clinic in a tertiary referral center. There were 166 patients studied: 53% men, 47% women, 86% white, 17% treated for hypertension. Seventy-six percent had an AER less than 20 micrograms/min, 18% had an AER of 20 to 200 micrograms/min, and 6% had an AER of greater than 200 micrograms/min. Glycosylated hemoglobin did not differ between groups. AER was increased with age and disease duration (P less than 0.005 by analysis of variance) after 10 yr of disease. Serum creatinine (P less than 0.005) and systolic (P less than 0.005) and diastolic (P less than 0.01) blood pressures were also increased with AER. Serum creatinine and blood pressure were found to be increased in parallel after 10 yr of disease, but both remained within the normal range overall. A comparison of individual blood pressures in patients not taking antihypertensive drugs (N = 138) with age-related blood pressures of nondiabetic subjects revealed increased systolic and diastolic blood pressures at all ages. Group comparison demonstrated a significant link between increased AER and serum creatinine (declining renal function) and increased blood pressure after a latent period of 10 yr. Blood pressure appears to be increased from the earliest age in diabetes compared with healthy populations.(ABSTRACT TRUNCATED AT 250 WORDS)