Oncologists' responsibility, comfort, and knowledge managing hyperglycemia in patients with cancer undergoing chemotherapy: a cross sectional study.

PURPOSE: To assess oncologists' responsibility, comfort, and knowledge managing hyperglycemia in patients undergoing chemotherapy. METHODS: In this cross-sectional study, a questionnaire collected oncologists' perceptions about professionals responsible for managing hyperglycemia during chemotherapy; comfort (score range 12-120); and knowledge (score range 0-16). Descriptive statistics were calculated including Student t-tests and one-way ANOVA for mean score differences. Multivariable linear regression identified predictors of comfort and knowledge scores. RESULTS: Respondents (N = 229) were 67.7% men, 91.3% White and mean age 52.1 years. Oncologists perceived endocrinologists/diabetologists and primary care physicians as those responsible for managing hyperglycemia during chemotherapy, and most frequently referred to these clinicians. Reasons for referral included lack of time to manage hyperglycemia (62.4%), belief that patients would benefit from referral to an alternative provider clinician (54.1%), and not perceiving hyperglycemia management in their scope of practice (52.4%). The top-3 barriers to patient referral were long wait times for primary care (69.9%) and endocrinology (68.1%) visits, and patient's provider outside of the oncologist's institution (52.8%). The top-3 barriers to treating hyperglycemia were lack of knowledge about when to start insulin, how to adjust insulin, and what insulin type works best. Women (ß = 1.67, 95% CI: 0.16, 3.18) and oncologists in suburban areas (ß = 6.98, 95% CI: 2.53, 11.44) had higher comfort scores than their respective counterparts; oncologists working in practices with > 10 oncologists had lower comfort scores (ß = -2.75, 95% CI: -4.96, -0.53) than those in practices with ≤ 10. No significant predictors were identified for knowledge. CONCLUSION: Oncologists expected endocrinology or primary care clinicians to manage hyperglycemia during chemotherapy, but long wait times were among the top barriers cited when referring patients. New models that provide prompt and coordinated care are needed.

Cystic fibrosis-related diabetes: The patient perspective.

Cystic fibrosis-related diabetes (CFRD) affects nearly 20% of adolescents and 40-50% of adults. However, the impact on patients and their families is poorly understood. Here, we examine how patients perceive CFRD and identify gaps in our understanding of the patient experience. Despite its relatively high prevalence, data suggest that many individuals are not aware of the possibility of developing CFRD or compare it to other types of diabetes. Annual oral glucose tolerance testing (OGTT) may serve as an opportunity to provide education and prepare individuals for the possibility of developing abnormalities in glucose tolerance. Many cite lack of awareness of CFRD as the most difficult part of the diagnosis. While factors such as older age and a strong support system promote acceptance, most individuals view the diagnosis negatively and struggle to balance the demands of diabetes with other obligations, including airway clearance, nebulizer therapies, supplementation nutrition, and administration of vitamins and medications. Relatively few people with CFRD monitor their blood glucoses consistently, which is attributed to time constraints or an attempt to avoid pain. In addition, many feel that they are not prone to hypoglycemia and are not concerned with long-term complications, anticipating that they will succumb to their pulmonary disease before these become problematic. The adolescent period presents unique challenges for adherence as children work to develop autonomy. Factors that promote CFRD adherence include incorporating management into daily CF routines and the support of knowledgeable providers to help develop an individualized approach to management. Diabetes technology has the potential to reduce treatment burden and improve glycemic control, but data in CFRD are limited, and additional study is needed. Given that CFRD is associated with a decline in health-related quality of life, it is critical that providers understand patients' perspectives and address gaps in understanding and barriers to management.

Growth failure and treatment in cystic fibrosis.

Poor growth has long been a characteristic feature of cystic fibrosis (CF) and is significantly linked to lung function and overall health status. Improvements in pulmonary and nutrition care for patients with cystic fibrosis (CF) have resulted in better growth outcomes; however, height gains have not paralleled the improvements in weight in children with CF, and patients with more severe CF mutations remain significantly more affected. Many factors affect the growth hormone-IGF-1 axis and the growth plate of the long bones, including the chronic inflammatory state associated with CF. There are also increasing data on the direct effects of CFTR on bone and implications for CFTR modulators in attaining optimal growth. Treatments aimed at improving growth in CF are also reviewed here.

Updates in vitamin D therapy in cystic fibrosis.

PURPOSE OF REVIEW: To summarize recent developments the role of vitamin D and treatment of vitamin D deficiency in cystic fibrosis. RECENT FINDINGS: Although treatment of low vitamin D levels continues to be important for optimizing bone health in cystic fibrosis, increasing data on the extraskeletal effects of vitamin D are becoming available. Exploratory studies of vitamin D in modulation of respiratory and intestinal microbiomes, and the influence of vitamin D on the metabolomic signature of cystic fibrosis, suggest expanded roles for vitamin D in cystic fibrosis disease and treatment. SUMMARY: Emerging developments in cystic fibrosis regarding therapeutics and effects of vitamin D on bone health, inflammation, microbiome, and the metabolome are summarized.

Insulin sensitizers in adolescents with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is the most common disorder of androgen excess in women of reproductive age. The diagnosis of PCOS can be more challenging in adolescents than in adult women given significant overlap between normal puberty and the signs of PCOS, including acne, menstrual irregularity, and polycystic ovarian morphology. Optimal treatments for adult women with PCOS vary depending on patient risk factors and reproductive goals, but mainly include hormonal contraception and insulin sensitizers. There is continued interest in targeting the intrinsic insulin resistance that contributes to metabolic and hormonal derangements associated with PCOS. The vast majority of published data on insulin sensitizing PCOS treatments are reported in adult women; these have included weight loss, metformin, thiazolidinediones, and the inositols. Furthermore, there is also a small but growing body of evidence in support of the use of insulin sensitizers in adolescents, with or without oral contraceptives. Discussion of the available treatments, including benefits, potential side effects, and incorporation of patient and family preferences is critical in developing a plan of care aimed at achieving patient-important improvements in PCOS signs and symptoms while addressing the longer-term cardiometabolic risks associated with the syndrome.

Sex hormone-binding globulin and type 2 diabetes mellitus.

Sex hormone-binding globulin (SHBG) has emerged as one of the multiple genetic and environmental factors that potentially contribute to the pathophysiology of type 2 diabetes mellitus (T2DM). In addition to epidemiologic studies demonstrating a consistent relationship between decreased levels of serum SHBG and incident T2DM, recent genetic studies also reveal that transmission of specific polymorphisms in the SHBG gene influence the risk of T2DM. At the molecular level, the multiple interactions between SHBG and its receptors in various target tissues suggest physiologic roles for SHBG that are more complex than the simple transport of sex hormones in serum. Taken together, these data provide support for an expanded role of SHBG in the pathophysiology of insulin resistance and T2DM.

Comparison of monoclonal antibodies to estradiol obtained from structurally different immunogens.

The immunization procedure and immunogen characteristics required to optimize the production of anti-steroid monoclonal antibodies have been studied. Five different estradiol-bovine serum albumin conjugates were tested for immunizing mice, as were two different immunization protocols (high and low dose) and the effect of varying the myeloma/spleen cell ratio for cell fusion. Antibody-producing hybridomas, obtained using the spleens of 9 high anti-steroid titre mice, were detected by RIA and EIA. The latter method was less specific than the former for higher affinity anti-estrogen antibodies. All the immunogens elicited anti-estrogen antibodies and the efficiency appeared related to the steroid density on the immunogen rather than the chemical nature of the derivative or the immunization and fusion protocols. Thirty-six anti-estrogen producing hybridomas were detected. Comparison showed that all the immunogens elicited antibodies in a wide range of affinities and specificities. None of the antibodies recognized corticosteroids or progesterone. Cross reactions with testosterone and other estrogens were not clearly related to the nature of the immunogen except that estradiol coupled to the BSA via its carbon 17 yielded antibodies specific for steroids with a non-derivatized phenolic A-ring.

Murine monoclonal antibody against aldosterone: production, characterization and use for enzymoimmunoassay.

Hybridomas secreting monoclonal antibodies to aldosterone were obtained by fusion of myeloma cells and spleen cells from Balb/c mice immunized with aldosterone-3-carboxylmethyloxime-bovine serum albumin. A monoclonal antibody was purified from ascites fluid and characterized. An affinity constant of 1.61 x 10(9) M-1 has been measured and no cross-reactivity with tetrahydroaldosterone (THA), cortisol, cortisone, corticosterone, deoxycorticosterone (DOC), dehydroepiandrosterone (DHA), progesterone and estrone, could be detected. A peroxidase conjugated-antibody (1.5 mole of enzyme per mole of antibody) was obtained and used for microwell enzyme immunoassay and Immun-Blot assay. The high affinity and specificity of this antibody should make the direct determination of aldosterone in biological fluids possible at concentrations as low as 5 x 10(-10) M.

Purification of cachectin, a lipoprotein lipase-suppressing hormone secreted by endotoxin-induced RAW 264.7 cells.

Previous studies have indicated that endotoxin and other bacterial and protozoal products can stimulate macrophages to produce a factor that can suppress the activity of the enzyme lipoprotein lipase (LPL), in vivo and in vitro. In the present report we describe the purification of this factor, cachectin, to apparent homogeneity from the conditioned medium of endotoxin-stimulated RAW 264.7 cells. The isolated protein has an isoelectric point of 4.7 and a subunit molecular weight of 17,000. Although cachectin's isoelectric point and molecular weight are similar to those described for interleukin 1, pure cachectin has no leukocyte-activating factor (LAF) activity. Cachectin at a concentration of 10(-11) M has the ability to suppress the LPL activity of the 3T3-L1 adipocyte cell line by 80%. Binding studies using radio-labeled cachectin and 3T3-L1 adipocytes and C2 myotubules revealed approximately 10(4) high-affinity receptors per cell on both cell types (Ka, 3 X 10(9]. Cachectin receptors were also present on liver membranes but were absent on erythrocytes and lymphocytes. The isolation of cachectin and characterization of its receptor should facilitate further investigations into the role of cachectin and other macrophage mediators in the metabolic derangements that occur during infection and cachexia.

Lipopolysaccharide-treated RAW 264.7 cells produce a mediator that inhibits lipoprotein lipase in 3T3-L1 cells.

RAW 264.7 cells upon stimulation with lipopolysaccharide secrete a protein mediator(s) that suppresses lipoprotein lipase activity in differentiated 3T3-L1 cells. The mediator(s), which is absent from unstimulated culture supernatants, is nondialyzable and thermolabile. Preliminary characterization suggests that this mediator(s) may be the same as that previously found in medium from lipopolysaccharide-treated thioglycollate-elicited mouse peritoneal macrophage cultures.

Weight loss associated with an endotoxin-induced mediator from peritoneal macrophages: the role of cachectin (tumor necrosis factor).

Endotoxin-induced cells of the reticuloendothelial system were shown to produce mediator(s) that evoke a state of cachexia in recipient animals. The factor(s) responsible were assayed in endotoxin-resistant (C3H/HeJ) mice, which were injected with dialyzed conditioned medium obtained from lipopolysaccharide-induced peritoneal macrophages. The mice exhibited weight loss and anorexia, and they died if sufficient quantities of medium were administered. The syndrome was reversible if injections were discontinued. Endotoxin alone did not produce this effect, and no gross pathologic lesions were discernable in the treated animals. In this model system, cachexia appears to result from the action of soluble macromolecules produced by activated macrophages in vitro. Cachectin (murine tumor necrosis factor) is thought to play a central role in this phenomenon.

Effect of arsenical drugs on glutathione metabolism of Litomosoides carinii.

Despite centuries of therapeutic use, the mechanism of action of arsenicals against various diseases remains unknown. Because of the known inhibition of sulfhydryl-containing enzymes by arsenicals, we investigated the possibility that the anti-filarial effects of arsenical drugs might be exerted specifically through impairment of parasite thiol metabolism. We find: (1) arsenicals readily inhibit glutathione reductase of Litomosoides carinii but have little effect upon mammalian enzyme. (2) Administration of Melarsen B to filaria-infected gerbils causes decreases in filarial - but not host - glutathione reductase and reduced glutathione. (3) Such in vivo treatment does not, however, acutely affect parasite energy (ATP) metabolism. These results support the proposition that arsenicals may act through preferential interference with parasite thiol metabolism. The much greater susceptibility of parasite glutathione reductase to inhibition by arsenicals suggests that this enzyme may be a useful point of attack for new drugs.