Increased Protein with Decreased Carbohydrate Intake Reduces Postprandial Blood Glucose Levels in Women with Gestational Diabetes: The iPRO Study.

Introduction: There is an urgent need to establish an evidence base for recommendations regarding proportions of macronutrients for optimized nutritional management of gestational diabetes mellitus (GDM). Our study compared isocaloric diets in women with GDM that differed in protein and carbohydrate content with fats held constant. We hypothesized that the glucose area under the curve (AUC) would be lower with the higher protein/lower carbohydrate diet. Research Design and Methods: This study used a random order crossover design within a controlled research unit environment. Nineteen women were randomized to treatment, with 12 participants completing both arms of the study. Blood sampling occurred preprandially and at t = 30, 60, 120, and 180" relative to meals. Inclusion criteria were confirmed diet-controlled GDMA1, singleton gestation, and with no pre-existing medical comorbidities. Mean gestational age at entrance to study = 32 (±1.76) weeks. Mean prepregnant body mass index of participants = 28.7 (±5.3) kg/m2 Participants were randomly assigned initially to either an increased protein/low carbohydrate (iPRO30%/CHO35%) diet or a lower protein/higher carbohydrate (LPRO15%/CHO50%) diet for a 36 hour inpatient stay on the research unit. All meals and snacks were prepared in a metabolic kitchen. After a 3-7 day washout period, participants were randomized to the opposite treatment. Results: On day 2 (with confirmed overnight fasting), the average 3-hour pre- through postprandial glucose AUC was lower in iPRO30%/CHO35% treatment arm (17395.20 ± 2493.47 vs. 19172.47 ± 3484.31, p = 0.01). Conclusion: This study is the first to demonstrate that a higher protein, lower carbohydrate meal, especially at breakfast, can result in lower postprandial blood glucose values in women with gestational diabetes. A lack of statistically significant differences at other collection time points could have been due to several factors, but most likely due to small sample size. Longer term outcomes of a higher protein diet, including maternal glycemic control, nitrogen balance, and impact on fetal growth outcomes, are needed.

Change in the immunophenotype of a somatotroph adenoma resulting in gigantism.

BACKGROUND: Examining the pathologic progression of a pituitary adenoma from the point of a prepubescent child to an adult with gigantism affords us an opportunity to consider why patients may develop secretory or functioning tumors and raises questions about whether therapeutic interventions and surveillance strategies could be made to avoid irreversible phenotypic changes. CASE DESCRIPTION: A patient underwent a sublabial transsphenoidal resection for a clinically non-functioning macroadenoma in 1999. He underwent radiation treatment and was transiently given growth hormone (GH) supplementation as an adolescent. His growth rapidly traversed several percentiles and he was found to have elevated GH levels. The patient became symptomatic and was taken for a second neurosurgical procedure. Pathology and immunohistochemical staining demonstrated a significantly higher proportion of somatotroph cells and dense granularity; he was diagnosed with a functional somatotroph adenoma. CONCLUSIONS: While it is likely that the described observations reflect the manifestations of a functional somatotroph adenoma in development, it is possible that pubertal growth, GH supplementation, its removal, or radiation therapy contributed to the described endocrine and pathologic changes.

Tear osmolarity and dry eye symptoms in diabetics.

PURPOSE: To assess the relationship between tear osmolarity and dry eye symptoms in patients with diabetes. PATIENTS AND METHODS: Fifty patients with diabetes were enrolled. Demographic information and past medical history were recorded. Symptoms were assessed using the ocular surface disease index (OSDI). Tear osmolarity of each eye was measured with the TearLab® Osmolarity System. RESULTS: The majority of the subjects were female (76%), African American (56%), and/or had a diagnosis of type 2 diabetes (82%). The mean ± standard deviation (SD) for age was 54.6±13.4, and maximum tear osmolarity was 304.6±12.7 mOsm/L. Men had higher osmolarity than women (mean ± standard error (SE) 311.8±4.0 mOsm/L versus 302.3±1.9 mOsm/L, P=0.02). Age, race, use of artificial tears, years of diabetes, and hemoglobin A1c did not have a statistically significant association with tear osmolarity. Longer duration of diabetes was associated with lower (less severe) OSDI scores (r=-0.35, P=0.01). Higher tear osmolarity was associated with lower (less severe) OSDI scores (r=-0.29, P=0.04). CONCLUSION: Approximately half of the diabetic subjects in our study had elevated tear osmolarity, and half of our population also reported symptoms consistent with dry eye disease. However, the two were slightly inversely related in that those with higher osmolarity reported fewer symptoms. Subjects with a longer duration of diabetes also reported fewer dry eye symptoms. Therefore, health care providers should be aware that patients who are most likely to have ocular surface disease, including those with long-standing diabetes, may not experience symptoms and seek care in a timely manner.

Clinical review: The human experience with ghrelin administration.

CONTEXT: Ghrelin is an endogenous stimulator of GH and is implicated in a number of physiological processes. Clinical trials have been performed in a variety of patient populations, but there is no comprehensive review of the beneficial and adverse consequences of ghrelin administration to humans. EVIDENCE ACQUISITION: PubMed was utilized, and the reference list of each article was screened. We included 121 published articles in which ghrelin was administered to humans. EVIDENCE SYNTHESIS: Ghrelin has been administered as an infusion or a bolus in a variety of doses to 1850 study participants, including healthy participants and patients with obesity, prior gastrectomy, cancer, pituitary disease, diabetes mellitus, eating disorders, and other conditions. There is strong evidence that ghrelin stimulates appetite and increases circulating GH, ACTH, cortisol, prolactin, and glucose across varied patient populations. There is a paucity of evidence regarding the effects of ghrelin on LH, FSH, TSH, insulin, lipolysis, body composition, cardiac function, pulmonary function, the vasculature, and sleep. Adverse effects occurred in 20% of participants, with a predominance of flushing and gastric rumbles and a mild degree of severity. The few serious adverse events occurred in patients with advanced illness and were not clearly attributable to ghrelin. Route of administration may affect the pattern of adverse effects. CONCLUSIONS: Existing literature supports the short-term safety of ghrelin administration and its efficacy as an appetite stimulant in diverse patient populations. There is some evidence to suggest that ghrelin has wider ranging therapeutic effects, although these areas require further investigation.

Hopping of a single hole in hexakis[4-(1,1,2-triphenyl-ethenyl)phenyl]benzene cation radical through the hexaphenylbenzene propeller.

A versatile synthesis of a dendritic structure (5) is described in which six tetraphenylethylene moieties are connected to a central benzene ring in such a way that one of the phenyl rings of each tetraphenylethylene is also part of the propeller of the hexaphenylbenzene core. Observation of multiple oxidation waves in its cyclovoltammogram as well as an intense charge-resonance transition in the near-IR region in its cation radical spectrum suggests that a single hole delocalizes via electron transfer over six identical redox-active centers. [structure--see text]

Synthesis and isolation of polytrityl cations by utilizing hexaphenylbenzene and tetraphenylmethane scaffolds.

The successful isolation of stable (and soluble) hexa- and tetratrityl cations based on hexaphenylbenzene and tetraphenylmethane scaffold has been accomplished by using readily available starting materials. These robust polytrityl cations can be isolated in crystalline form and stored indefinitely at 0 degrees C. Their structures have been established by (1)H/(13)C NMR spectroscopy and by UV-vis spectroscopy. The structures of these polytrityl cations were further confirmed by quantitative transformations to the reduced (poly)triphenylmethyl derivatives by hydride transfer from triethylsilane, cycloheptatriene, or a borane-dimethyl sulfide complex.

A practical one-pot synthesis of soluble hexa-peri-hexabenzocoronene and isolation of its cation-radical salt.

A simple and practical synthesis of soluble hexa-peri-hexabenzocoronene (HBC) from readily available hexaphenylbenzene (HPB) is described. In this simple procedure, the substitution of the free para positions of the propeller-shaped HPB with tert-butyl groups and the oxidative cyclodehydrogenation to planar HBC is achieved in a one-pot reaction using ferric chloride both as a Lewis acid catalyst and as an oxidant in excellent yields. The ready availability of HBC allows the isolation of its pure cation-radical salt using a variety of chemical oxidants such as antimony pentachloride and triethyloxonium and nitrosonium hexachloroantimonate salts.

A remarkably efficient synthesis of pure cis-stilbenoid hydrocarbons using trans-dibromoalkenes via palladium catalysis.

A remarkably versatile synthesis of cis-stilbenoid hydrocarbons containing highly functionalized phenyl groups is developed via an efficient palladium-catalyzed coupling of aryl Grignard reagents with trans-1,2-dibromoalkenes (generally obtained via bromination of the corresponding dialkylacetylenes) in tetrahydrofuran.