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Objectives: This paper evaluates the association between psychological problems and cancer workup in children aged less than 20 and their parents. Assessment of the potential psychological stress in these children and their parents has been inadequately studied in the past. Methods: A retrospective cohort study of anxiety or depression among children and the parents of children undergoing cancer workup, based on Deseret Mutual Benefit Administrators (DMBA) claims data and corresponding enrollment files for dependent children aged less than 20, from 1998 to 2002 in the United States and Canada. Results: Less than 20% of cancer workups are followed by cancer diagnosis and treatment. Children with a 'cancer workup only' are 89% more likely to experience anxiety/depression than are children without a cancer-related claim; that is, the rate per 100,000 person-years of anxiety/depression is 7,222 for children with a cancer workup only compared with 3,824 for children without a cancer-related claim. Mothers of children with cancer workup are 37% more likely to experience anxiety/depression. Children are significantly more likely to experience anxiety/depression if one or both of their parents experience anxiety/depression. The increased risk is influenced by whether the child experiences both cancer workup and treatment (359% higher), by cancer workup only (308% higher), and by no cancer workup or treatment (295% higher). Finally, the rate of anxiety/depression among children with cancer workup and their mothers was significantly lower in homes with more children. Conclusions: A cancer workup alone is sufficient to significantly increase the risk of anxiety/depression in children undergoing cancer workup and in their parents. The ability of a child undergoing a cancer workup to cope is influenced by the mental health of their parents. More children in the home are protective against anxiety/depression in children undergoing cancer workup and in their mothers. [ABSTRACT FROM AUTHOR]

Objectives Cases of hypophosphataemia (often coincident with renal dysfunction) have been reported in HIV-infected patients taking tenofovir disoproxil fumarate (TDF), but randomized placebo-controlled trials of HIV-infected persons with normal baseline renal function have found a comparable incidence of hypophosphataemia in the TDF and placebo groups. We assessed the incidence of grade 2 and higher hypophosphataemia in the HIV Outpatient Study (HOPS). Methods We analysed a prospective cohort of patients who initiated either a TDF-containing highly active antiretroviral therapy (HAART) regimen [TDF-exposed (TDF+) group; n=165] or a TDF-sparing HAART regimen [TDF-unexposed (TDF–) group; n=90], and who had normal baseline phosphate and creatinine values. Results The TDF+and TDF−groups had comparable median follow-up times (10.9 vs 8.8 months, respectively; P=0.18) and number of phosphate measurements (median=3 for both) and were similar on most clinical and demographic factors. During follow up, 12.7% of TDF+vs 6.7% of TDF−patients developed grade 2 hypophosphataemia (2.0–2.4 mg/dL), and 2.4% of TDF+patients vs 0% of TDF−patients developed grade 3 hypophosphataemia (1.0–1.9 mg/dL); none developed grade 4 hypophosphataemia (<1.0 mg/dL). The incidence of grade 2 or higher hypophosphataemia was 16.7 per 100 person-years among TDF+patients vs 8.0 per 100 person-years among TDF−patients ( P=0.11). Conclusions The incidence of hypophosphataemia was somewhat elevated in HOPS patients who took TDF-containing HAART compared with those who took TDF-sparing HAART during the first 1 to 2 years of observation, but the difference was not statistically significant. Longer follow-up of a larger population is needed to determine if this trend towards an association achieves statistical significance and to evaluate the clinical consequences of hypophosphataemia. [ABSTRACT FROM AUTHOR]

Coadministration of didanosine (ddI) and tenofovir (TDF) results in increased ddI serum concentrations, which may lead to increased risk of ddI-associated toxicities. To evaluate the safety and tolerability of ddI/TDF, we performed a retrospective cohort analysis of patients seen in the HIV Outpatient Study, an ongoing dynamic cohort study of HIV-infected persons in clinical care. Study subjects were those who received at least 14 days of combined ddI/TDF before October 2003. Of 260 subjects who received ddI/TDF-based antiretroviral therapy, 155 (60%) received high-dose ddI (400 mg daily dose) and 105 (40%) received low-dose ddI (100-250 mg daily). Forty-two of the high-dose ddI recipients were later switched to low-dose ddI. The median time of observation for those on high-dose ddI only was 5 months, high-dose ddI switched to low-dose ddI was 16 months, and low-dose ddI only was 5 months (p < 0.05). Discontinuations because of toxicity were more frequent on high-dose ddI regimens (34/155, 22%) than on low-dose ddI regimens (9/105, 9%) (unadjusted odds ratio [OR(unadj)] 3.0, 95% confidence interval [95% CI] 1.30-7.09; p = 0.007). Among subjects without preexisting peripheral neuropathy, 12 (12%) of 101 subjects ever on high-dose ddI regimens had treatment-emergent peripheral neuropathy compared to 2 (4%) of 55 subjects on low-dose ddI regimens (OR(unadj) 3.57; 95% CI, 0.72-24.1; p = 0.14). Among patients without a history of pancreatitis, 6 (4%) of 153 subjects developed pancreatitis after starting high-dose ddI regimens, compared to none of the 103 subjects on low-dose ddI regimens (OR(adj) and 95% CIs undefined; p = 0.08). Severe laboratory abnormalities of creatinine, phosphorous, and bicarbonate were not different between the groups. A summary variable for any event--discontinuation for toxicity, treatment- emergent adverse event or abnormal laboratory values--indicated that 44 (28%) of 155 of those on high-dose ddI versus 13 (12%) of 105 on low-dose ddI developed any event (OR(unadj) 2.81; 95% CI, 1.36-5.86; p = 0.004). In conclusion, high-dose ddI/TDF-based therapy was more frequently associated with drug-related toxicity, adverse events, and treatment discontinuation than low-dose ddI/TDF regimens; low-dose ddI with TDF was generally well tolerated in these HIV-infected persons. [ABSTRACT FROM AUTHOR]

Remarkable advances in protocol development have been achieved to manufacture insulin-secreting islets from human pluripotent stem cells (hPSCs). Distinct from current approaches, we devised a tunable strategy to generate islet spheroids enriched for major islet cell types by incorporating PDX1+ cell budding morphogenesis into staged differentiation. In this process that appears to mimic normal islet morphogenesis, the differentiating islet spheroids organize with endocrine cells that are intermingled or arranged in a core-mantle architecture, accompanied with functional heterogeneity. Through in vitro modelling of human pancreas development, we illustrate the importance of PDX1 and the requirement for EphB3/4 signaling in eliciting cell budding morphogenesis. Using this new approach, we model Mitchell-Riley syndrome with RFX6 knockout hPSCs illustrating unexpected morphogenesis defects in the differentiation towards islet cells. The tunable differentiation system and stem cell-derived islet models described in this work may facilitate addressing fundamental questions in islet biology and probing human pancreas diseases., (© 2024. The Author(s).)

Background: Diabetes is a disease affecting over 500 million people globally due to insulin insufficiency or insensitivity. For individuals with type 1 diabetes, pancreatic islet transplantation can help regulate their blood glucose levels. However, the scarcity of cadaveric donor islets limits the number of people that could receive this therapy. To address this issue, human pluripotent stem cells offer a potentially unlimited source for generating insulin-producing cells through directed differentiation. Several protocols have been developed to make stem cell-derived insulin-producing cells. However, there is a lack of knowledge regarding the bioprocess parameters associated with these differentiation protocols and how they can be utilized to increase the cell yield., Methods: We investigated various bioprocess parameters and quality target product profiles that may influence the differentiation pipeline using a seven-stage protocol in a scalable manner with CellSTACKs and vertical wheel bioreactors (PBS-Minis)., Results: Cells maintained > 80% viability through all stages of differentiation and appropriately expressed stage-specific markers. During the initial four stages leading up to the development of pancreatic progenitors, there was an increase in cell numbers. Following pancreatic progenitor stage, there was a gradual decrease in the percentage of proliferative cells, as determined by Ki67 positivity, and a significant loss of cells during the period of endocrine differentiation. By minimizing the occurrence of aggregate fusion, we were able to enhance cell yield during the later stages of differentiation. We suggest that glucose utilization and lactate production are cell quality attributes that should be considered during the characterization of insulin-producing cells derived from stem cells. Our findings also revealed a gradual metabolic shift from glycolysis, during the initial four stages of pancreatic progenitor formation, to oxidative phosphorylation later on during endocrine differentiation. Furthermore, the resulting insulin-producing cells exhibited a response to several secretagogues, including high glucose., Conclusion: This study demonstrates process parameters such as glucose consumption and lactate production rates that may be used to facilitate the scalable manufacture of stem cell-derived insulin-producing cells., (© 2023. The Author(s).)

Introduction: Human pluripotent stem cells (hPSCs) provide many opportunities for application in regenerative medicine due to their ability to differentiate into cells from all three germ layers, proliferate indefinitely, and replace damaged or dysfunctional cells. However, such cell replacement therapies require the economical generation of clinically relevant cell numbers. Whereas culturing hPSCs as a two-dimensional monolayer is widely used and relatively simple to perform, their culture as suspended three-dimensional aggregates may enable more economical production in large-scale stirred tank bioreactors. To be more relevant to this biomanufacturing, bench-scale differentiation studies should be initiated from aggregated hPSC cultures. Methods: We compared five available bench-scale platforms for generating undifferentiated cell aggregates of human embryonic stem cells (hESCs) using AggreWell™ plates, low attachment plates on an orbital shaker, roller bottles, spinner flasks, and vertical-wheel bioreactors (PBS-Minis). Thereafter, we demonstrated the incorporation of an hPSC aggregation step prior to directed differentiation to pancreatic progenitors and endocrine cells. Results and discussion: The AggreWell™ system had the highest aggregation yield. The initial cell concentrations had an impact on the size of aggregates generated when using AggreWell™ plates as well as in roller bottles. However, aggregates made with low attachment plates, spinner flasks and PBS-Minis were similar regardless of the initial cell number. Aggregate morphology was compact and relatively homogenously distributed in all platforms except for the roller bottles. The size of aggregates formed in PBS-Minis was modulated by the agitation rate during the aggregation. In all cell culture platforms, the net growth rate of cells in 3D aggregates was lower (range: -0.01-0.022 h -1 ) than cells growing as a monolayer (range: 0.039-0.045 h -1 ). Overall, this study describes operating ranges that yield high-quality undifferentiated hESC aggregates using several of the most commonly used bench-scale cell culture platforms. In all of these systems, methods were identified to obtain PSC aggregates with greater than 70% viability, and mean diameters between 60 and 260 mm. Finally, we showed the capacity of hPSC aggregates formed with PBS-Minis to differentiate into viable pancreatic progenitors and endocrine cell types., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Iworima, Baker, Piret and Kieffer.)

Differentiation of human pluripotent stem cells (hPSCs) into insulin-secreting beta cells provides material for investigating beta cell function and diabetes treatment. However, challenges remain in obtaining stem cell-derived beta cells that adequately mimic native human beta cells. Building upon previous studies, hPSC-derived islet cells have been generated to create a protocol with improved differentiation outcomes and consistency. The protocol described here utilizes a pancreatic progenitor kit during Stages 1-4, followed by a protocol modified from a paper previously published in 2014 (termed "R-protocol" hereafter) during Stages 5-7. Detailed procedures for using the pancreatic progenitor kit and 400 µm diameter microwell plates to generate pancreatic progenitor clusters, R-protocol for endocrine differentiation in a 96-well static suspension format, and in vitro characterization and functional evaluation of hPSC-derived islets, are included. The complete protocol takes 1 week for initial hPSC expansion followed by ~5 weeks to obtain insulin-producing hPSC islets. Personnel with basic stem cell culture techniques and training in biological assays can reproduce this protocol.

Regular use of continuous glucose monitoring (CGM) in type 1 diabetes management increases the achievement of glycemic targets and reduces health care utilization, specifically emergency department (ED) visits. This retrospective chart review examined the effects of CGM use in patients with type 1 diabetes in a pediatric ED. Use of CGM was associated with several differences in patient management in the ED. This work is a first step toward development of guidelines for the appropriate use of CGM in the pediatric ED. In the future, CGM use in type 1 diabetes may lead to reduced ED-specific health care costs., Competing Interests: No potential conflicts of interest relevant to this article were reported., (© 2023 by the American Diabetes Association.)

The generation of functional β-cells from human pluripotent stem cells (hPSCs) for cell replacement therapy and disease modeling of diabetes is being investigated by many groups. We have developed a protocol to harvest and aggregate hPSC-derived pancreatic progenitors generated using a commercially available kit into near uniform spheroids and to further differentiate the cells toward an endocrine cell fate in suspension culture. Using a static suspension culture platform, we could generate a high percentage of insulin-expressing, glucose-responsive cells. We identified FGF7 as a soluble factor promoting aggregate survival with no inhibitory effect on endocrine gene expression. Notch inhibition of pancreatic progenitor cells during aggregation improved endocrine cell induction in vitro and improved graft function following implantation and further differentiation in mice. Thus we provide an approach to promote endocrine formation from kit-derived pancreatic progenitors, either through extended culture or post implant., (© 2023. The Author(s).)

Orbital shaker-based suspension culture systems have been in widespread use for differentiating human pluripotent stem cell (hPSC)-derived pancreatic progenitors toward islet-like clusters during endocrine induction stages. However, reproducibility between experiments is hampered by variable degrees of cell loss in shaking cultures, which contributes to variable differentiation efficiencies. Here, we describe a 96-well-based static suspension culture method for differentiation of pancreatic progenitors into hPSC-islets. Compared with shaking culture, this static 3D culture system induces similar islet gene expression profiles during differentiation processes but significantly reduces cell loss and improves cell viability of endocrine clusters. This static culture method results in more reproducible and efficient generation of glucose-responsive, insulin-secreting hPSC-islets. The successful differentiation and well-to-well consistency in 96-well plates also provides a proof of principle that the static 3D culture system can serve as a platform for small-scale compound screening experiments as well as facilitating further protocol development., Competing Interests: T.J.K. was an employee of ViaCyte during the preparation of this manuscript., (© 2023 The Author(s).)

Few studies have examined the differentiation of human embryonic stem cell (hESC)-derived pancreatic endoderm cells (PECs) in different implantation sites. Here, we investigate the influence of implantation site and recipient sex on the differentiation of hESC-derived PECs in vivo. Male and female mice were implanted with 5 × 106 hESC-derived PECs under the kidney capsule, in the gonadal fat pad, or subcutaneously within macroencapsulation (TheraCyte) devices. PECs implanted within TheraCyte devices developed glucose-stimulated human C-peptide secretion faster than cells implanted under the kidney capsule or in the gonadal fat pad. Interestingly, hESC-derived PECs implanted under the kidney capsule in females developed glucose-stimulated human C-peptide faster than in males and secreted higher levels of arginine-stimulated glucagon and glucagon-like peptide 1 than other implantation sites. Furthermore, hESC-derived grafts collected from the kidney capsule and gonadal fat pad sites displayed a mix of endocrine and ductal cells as well as contained cysts, whereas TheraCyte device grafts displayed mostly endocrine cells and cysts were not observed. Here we demonstrate that the macroencapsulated subcutaneous site and the female recipient can promote faster differentiation of hESC-derived PECs to endocrine cells in mice., Article Highlights: Few studies have directly compared the differentiation of human embryonic stem cell-derived progenitors in different implantation sites in male and female recipients. We investigated whether the site of implantation and/or the sex of the recipient influenced the differentiation of pancreatic progenitors in vivo in mice. Mice implanted with cells in macroencapsulation devices contained fewer off-target structures and developed stimulated insulin release faster than other implant sites, while females implanted with cells under the kidney capsule developed stimulated insulin release before males. Macroencapsulation devices reduced the formation of off-target cells from human embryonic stem cell-derived progenitors, a useful characteristic for clinical applications., (© 2023 by the American Diabetes Association.)

Up to 6% of diabetes has a monogenic cause including mutations in the insulin gene, and patients are candidates for a gene therapy. Using a mouse model of permanent neonatal diabetes, we assessed the efficacy of an adeno-associated virus (AAV)-mediated gene therapy. We used AAVs with a rat insulin 1 promoter (Ins1) regulating a human insulin gene (INS; AAV Ins1-INS) or native mouse insulin 1 (Ins1; AAV Ins-Ins1) to deliver an insulin gene to β-cells of constitutive insulin null mice (Ins1-/-Ins2-/-) and adult inducible insulin-deficient mice [Ins1-/-Ins2f/f PdxCreER and Ins1-/-Ins2f/f mice administered AAV Ins1-Cre)]. Although AAV Ins1-INS could successfully infect and confer insulin expression to β-cells, insulin null β-cells had a prohormone processing defect. Secretion of abundant proinsulin transiently reversed diabetes. We reattempted therapy with AAV Ins1-Ins1, but Ins1-/-Ins2-/- β-cells still had a processing defect of both replaced Ins1 and pro-islet amyloid polypeptide (proIAPP). In adult inducible models, β-cells that lost insulin expression developed a processing defect that resulted in impaired proIAPP processing and elevated circulating proIAPP, and cells infected with AAV Ins1-Ins1 to rescue insulin expression secreted proinsulin. We assessed the subcellular localization of prohormone convertase 1/3 (PC1/3) and detected defective sorting of PC1/3 to glycogen-containing vacuoles and retention in the endoplasmic reticulum as a potential mechanism underlying defective processing. We provide evidence that persistent production of endogenous proinsulin within β-cells is necessary for β-cells to be able to properly store and process proinsulin., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

miRNAs have crucial functions in many biological processes and are candidate biomarkers of disease. Here, we show that miR-216a is a conserved, pancreas-specific miRNA with important roles in pancreatic islet and acinar cells. Deletion of miR-216a in mice leads to a reduction in islet size, β-cell mass, and insulin levels. Single-cell RNA sequencing reveals a subpopulation of β-cells with upregulated acinar cell markers under a high-fat diet. miR-216a is induced by TGF-β signaling, and inhibition of miR-216a increases apoptosis and decreases cell proliferation in pancreatic cells. Deletion of miR-216a in the pancreatic cancer-prone mouse line Kras G12D ;Ptf1a CreER reduces the propensity of pancreatic cancer precursor lesions. Notably, circulating miR-216a levels are elevated in both mice and humans with pancreatic cancer. Collectively, our study gives insights into how β-cell mass and acinar cell growth are modulated by a pancreas-specific miRNA and also suggests miR-216a as a potential biomarker for diagnosis of pancreatic diseases., Competing Interests: The authors declare no competing interests., (© 2021 The Author(s).)

Although innate immunity is linked to metabolic health, the effect of leptin signaling in cells from the innate immune system on glucose homeostasis has not been thoroughly investigated. We generated two mouse models using Cre-lox methodology to determine the effect of myeloid cell-specific leptin receptor (Lepr) reconstitution and Lepr knockdown on in vivo glucose metabolism. Male mice with myeloid cell-specific Lepr reconstitution (Lyz2Cre + Lepr loxTB/loxTB ) had better glycemic control as they aged compared to male mice with whole-body transcriptional blockade of Lepr (Lyz2Cre - Lepr loxTB/loxTB ). In contrast, Lyz2Cre + Lepr loxTB/loxTB females only had a trend for diminished hyperglycemia after a prolonged fast. During glucose tolerance tests, Lyz2Cre + Lepr loxTB/loxTB males had a mildly improved plasma glucose profile compared to Cre - controls while Lyz2Cre + Lepr loxTB/loxTB females had a similar glucose excursion to their Cre - controls. Myeloid cell-specific Lepr knockdown (Lyz2Cre + Lepr flox/flox ) did not significantly alter body weight, blood glucose, insulin sensitivity, or glucose tolerance in males or females. Expression of the cytokine interleukin 10 (anti-inflammatory) tended to be higher in adipose tissue of male Lyz2Cre + Lepr loxTB/loxTB mice (p = 0.0774) while interleukin 6 (pro-inflammatory) was lower in male Lyz2Cre + Lepr flox/flox mice (p < 0.05) vs. their respective controls. In conclusion, reconstitution of Lepr in cells of myeloid lineage has beneficial effects on glucose metabolism in male mice., (© 2021. The Author(s).)

In vivo genetic manipulation is used to study the impact of gene deletion or re-expression on β-cell function and organism physiology. Cre-LoxP is a system wherein LoxP sites flanking a gene are recognized by Cre recombinase. Cre transgenic mice are the most prevalent technology used to deliver Cre but many models have caveats of off-target recombination, impaired β-cell function, and high cost of animal production. Inducible estrogen receptor conjugated Cre models face leaky recombination and confounding effects of tamoxifen. As an alternative, we characterize an adeno associated virus (AAV) with a rat insulin 1 promoter driving Cre recombinase (AAV8 Ins1-Cre) that is economical and rapid to implement, and has limited caveats. Intraperitoneal AAV8 Ins1-Cre produced efficient β-cell recombination, alongside some hepatic, exocrine pancreas, α-cell, δ-cell, and hypothalamic recombination. Delivery of lower doses via the pancreatic duct retained good rates of β-cell recombination and limited rates of off-target recombination. Unlike inducible Cre in transgenic mice, AAV8 Ins1-Cre required no tamoxifen and premature recombination was avoided. We demonstrate the utility of this technology by inducing hyperglycemia in inducible insulin knockout mice (Ins1 -/- ;Ins2 f/f ). AAV-mediated expression of Cre in β-cells provides an effective alternative to transgenic approaches for inducible knockout studies.

SNAP23 is the ubiquitous SNAP25 isoform that mediates secretion in non-neuronal cells, similar to SNAP25 in neurons. However, some secretory cells like pancreatic islet β cells contain an abundance of both SNAP25 and SNAP23, where SNAP23 is believed to play a redundant role to SNAP25. We show that SNAP23, when depleted in mouse β cells in vivo and human β cells (normal and type 2 diabetes [T2D] patients) in vitro, paradoxically increased biphasic glucose-stimulated insulin secretion corresponding to increased exocytosis of predocked and newcomer insulin granules. Such effects on T2D Goto-Kakizaki rats improved glucose homeostasis that was superior to conventional treatment with sulfonylurea glybenclamide. SNAP23, although fusion competent in slower secretory cells, in the context of β cells acts as a weak partial fusion agonist or inhibitory SNARE. Here, SNAP23 depletion promotes SNAP25 to bind calcium channels more quickly and longer where granule fusion occurs to increase exocytosis efficiency. β Cell SNAP23 antagonism is a strategy to treat diabetes.

The study of primary glucagon-secreting α-cells is hampered by their low abundance and scattered distribution in rodent pancreatic islets. We have designed a double-stranded adeno-associated virus containing a rat proglucagon promoter (700 bp) driving enhanced green fluorescent protein (AAV GCG-EGFP), to specifically identify α-cells. The administration of AAV GCG-EGFP by intraperitoneal or intraductal injection led to EGFP expression selectively in the α-cell population. AAV GCG-EGFP delivery to mice followed by islet isolation, dispersion and separation by FACS for EGFP resulted in an 86% pure population of α-cells. Furthermore, the administration of AAV GCG-EGFP at various doses to adult wild type mice did not significantly alter body weight, blood glucose, plasma insulin or glucagon levels, glucose tolerance or arginine tolerance. In vitro experiments in transgene positive α-cells demonstrated that EGFP expression did not alter the intracellular Ca 2+ pattern in response to glucose or adrenaline. This approach may be useful for studying purified primary α-cells and for the in vivo delivery of other genes selectively to α-cells to further probe their function or to manipulate them for therapeutic purposes.

The relative contribution of peripheral and central leptin signalling to the regulation of metabolism and the mechanisms through which leptin affects glucose homeostasis have not been fully elucidated. We generated complementary lines of mice with either leptin receptor (Lepr) knockdown or reconstitution in adipose tissues using Cre-lox methodology. Lepr knockdown mice were modestly lighter and had lower plasma insulin concentrations following an oral glucose challenge compared to controls, despite similar insulin sensitivity. We rendered male mice diabetic using streptozotocin (STZ) and found that upon prolonged leptin therapy, Lepr knockdown mice had an accelerated decrease in blood glucose compared to controls that was associated with higher plasma concentrations of leptin and leptin receptor. Mice with transcriptional blockade of Lepr (Lepr loxTB/loxTB ) were obese and hyperglycemic and reconstitution of Lepr in adipose tissues of Lepr loxTB/loxTB mice resulted in males reaching a higher maximal body weight. Although mice with adipose tissue Lepr reconstitution had lower blood glucose levels at several ages, their plasma insulin concentrations during an oral glucose test were elevated. Thus, attenuation or restoration of Lepr in adipocytes alters the plasma insulin profile following glucose ingestion, modifies the glucose-lowering effect of prolonged leptin therapy in insulin-deficient diabetes, and may modulate weight gain.

It was long thought that the only hormone capable of reversing the catabolic consequences of diabetes was insulin. However, various studies have demonstrated that the adipocyte-derived hormone leptin can robustly lower blood glucose levels in rodent models of insulin-deficient diabetes. In addition, it has been suggested that some of the metabolic manifestations of insulin-deficient diabetes are due to hypoleptinemia as opposed to hypoinsulinemia. Because insulin therapy increases leptin levels, we sought to investigate the contribution of leptin to the beneficial effects of insulin therapy. To do this, we tested insulin therapy in streptozotocin (STZ) diabetic mice that were either on an ob/ ob background or that were given a leptin antagonist to determine if blocking leptin action would blunt the glucose-lowering effects of insulin therapy. We found that STZ diabetic ob/ ob mice have a diminished blood glucose-lowering effect in response to insulin therapy compared with STZ diabetic controls and exhibited more severe weight loss post-STZ injection. In addition, STZ diabetic mice administered a leptin antagonist through daily injection or plasmid expression respond less robustly to insulin therapy as assessed by both fasting blood glucose levels and blood glucose levels during an oral glucose tolerance test. However, leptin antagonism did not prevent the insulin-induced reduction in β-hydroxybutyrate and triglyceride levels. Therefore, we conclude that elevated leptin levels can contribute to the glucose-lowering effect of insulin therapy in insulin-deficient diabetes.

With more than 29,000 OpenSim users, several musculoskeletal models with varying levels of complexity are available to study human gait. However, how different model parameters affect estimated joint and muscle function between models is not fully understood. The purpose of this study is to determine the effects of four OpenSim models (Gait2392, Lower Limb Model 2010, Full-Body OpenSim Model, and Full Body Model 2016) on gait mechanics and estimates of muscle forces and activations. Using OpenSim 3.1 and the same experimental data for all models, six young adults were scaled in each model, gait kinematics were reproduced, and static optimization estimated muscle function. Simulated measures differed between models by up to 6.5° knee range of motion, 0.012 Nm/Nm peak knee flexion moment, 0.49 peak rectus femoris activation, and 462 N peak rectus femoris force. Differences in coordinate system definitions between models altered joint kinematics, influencing joint moments. Muscle parameter and joint moment discrepancies altered muscle activations and forces. Additional model complexity yielded greater error between experimental and simulated measures; therefore, this study suggests Gait2392 is a sufficient model for studying walking in healthy young adults. Future research is needed to determine which model(s) is best for tasks with more complex motion.

The New Zealand Neuromuscular Disease Patient Registry has been recruiting for five years. Its primary aim is to enable people with neuromuscular disease to participate in research including clinical trials. It has contributed data to large anonymised cohort studies and many feasibility studies, and has provided practical information and advice to researchers wanting to work with people with neuromuscular conditions. 1019 people have enrolled since the Registry's launch in August 2011 with over 70 different diagnoses. Of these; 8 patients have been involved in clinical trials, 134 in other disease-specific research and 757 have contributed anonymised data to cohort studies. As a result the Registry is now effectively facilitating almost all neuromuscular research currently taking place in New Zealand.

The in vitro differentiation of human embryonic stem cells (hESCs) offers a model system to explore human development. Humans with mutations in the transcription factor Aristaless Related Homeobox (ARX) often suffer from the syndrome X-linked lissencephaly with ambiguous genitalia (XLAG), affecting many cell types including those of the pancreas. Indeed, XLAG pancreatic islets lack glucagon and pancreatic polypeptide-positive cells but retain somatostatin, insulin, and ghrelin-positive cells. To further examine the role of ARX in human pancreatic endocrine development, we utilized genomic editing in hESCs to generate deletions in ARX. ARX knockout hESCs retained pancreatic differentiation capacity and ARX knockout endocrine cells were biased toward somatostatin-positive cells (94% of endocrine cells) with reduced pancreatic polypeptide (rarely detected), glucagon (90% reduced) and insulin-positive (65% reduced) lineages. ARX knockout somatostatin-positive cells shared expression patterns with human fetal and adult δ-cells. Differentiated ARX knockout cells upregulated PAX4, NKX2.2, ISL1, HHEX, PCSK1, PCSK2 expression while downregulating PAX6 and IRX2. Re-expression of ARX in ARX knockout pancreatic progenitors reduced HHEX and increased PAX6 and insulin expression following differentiation. Taken together these data suggest that ARX plays a key role in pancreatic endocrine fate specification of pancreatic polypeptide, somatostatin, glucagon and insulin positive cells from hESCs.

Fibroblast growth factor 21 (FGF21)-mediated weight loss and improvements in glucose metabolism correlate with increased uncoupling protein 1 (Ucp1) levels in adipose tissues, suggesting that UCP1-dependent thermogenesis may drive FGF21 action. It was reported that FGF21 is equally effective at reducing body weight and improving glucose homeostasis without UCP1. We find while FGF21 can lower body weight in both wild-type and Ucp1 knockout mice, rapid clearance of glucose by FGF21 is defective in the absence of UCP1. Furthermore, in obese wild-type mice there is a fall in brown adipose tissue (BAT) temperature during glucose excursion, and FGF21 improves glucose clearance while preventing the fall in BAT temperature. In Ucp1 knockout mice, the fall in BAT temperature during glucose excursion and FGF21-mediated changes in BAT temperature are lost. We conclude FGF21-mediated improvements in clearance of a glucose challenge require UCP1 and evoke UCP1-dependent thermogenesis as a method to increase glucose disposal., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

The contribution of peroxisomal proliferator-activated receptor (PPAR)-γ agonism in pancreatic β-cells to the antidiabetic actions of thiazolidinediones has not been clearly elucidated. Genetic models of pancreatic β-cell PPARγ ablation have revealed a potential role for PPARγ in β-cell expansion in obesity but a limited role in normal β-cell physiology. Here we overexpressed PPARγ1 or PPARγ2 specifically in pancreatic β-cells of mice subjected to high-fat feeding using an associated adenovirus (β-PPARγ1-HFD and β-PPARγ2-HFD mice). We show β-cell-specific PPARγ1 or PPARγ2 overexpression in diet-induced obese mice exacerbated obesity-induced glucose intolerance with decreased β-cell mass, increased islet cell apoptosis, and decreased plasma insulin compared with obese control mice (β-eGFP-HFD mice). Analysis of islet lipid composition in β-PPARγ2-HFD mice revealed no significant changes in islet triglyceride content and an increase in only one of eight ceramide species measured. Interestingly β-PPARγ2-HFD islets had significantly lower levels of lysophosphatidylcholines, lipid species shown to enhance insulin secretion in β-cells. Gene expression profiling revealed increased expression of uncoupling protein 2 and genes involved in fatty acid transport and β-oxidation. In summary, transgenic overexpression of PPARγ in β-cells in diet-induced obesity negatively impacts whole-animal carbohydrate metabolism associated with altered islet lipid content, increased expression of β-oxidative genes, and reduced β-cell mass.

The ability of leptin to improve metabolic abnormalities in models of leptin deficiency, lipodystrophy, and even type 1 diabetes is of significant interest. However, the mechanism by which leptin mediates these effects remains ill-defined. Leptin was recently reported to regulate insulin-like growth factor-binding protein-2 (IGFBP2), and adenoviral overexpression of pharmacological levels of IGFBP2 ameliorates diabetic symptoms in many models of diabetes. We sought to determine the role of physiological levels of IGFBP2 in the glucoregulatory action of leptin. To investigate whether physiological levels of IGFBP2 are sufficient to mimic the action of leptin, we treated male ob/ob mice with low-dose IGFBP2 adenovirus (Ad-IGFBP2) or low-dose leptin. Despite similar levels of circulating IGFBP2, leptin but not Ad-IGFBP2 lowered body weight and plasma insulin and improved glucose and insulin tolerance. To elucidate the role of IGFBP2 in normal glucose homeostasis, we knocked down IGFBP2 in male C57BL/6 mice using small interfering RNA to determine whether this would recapitulate any aspect of the ob/ob phenotype. Despite successful IGFBP2 knockdown, body weight, blood glucose, and plasma insulin were unchanged. Finally, to determine whether IGFBP2 is required for the glucoregulatory actions of leptin, we prevented leptin-mediated increases in IGFBP2 in male ob/ob mice using RNA interference. Even though increases in IGFBP2 were blocked, the ability of leptin to decrease body weight, blood glucose, and plasma insulin levels were unaltered. In conclusion, physiological levels of IGFBP2 are neither sufficient to mimic nor required for the physiological action of leptin.

The goal of the present research was to examine whether infants associate different paths of motion with animate beings and inanimate objects. An infant-controlled habituation procedure was used to examine 10-20-month-old infants' ability to associate a non-linear motion path (jumping) with animals and a linear (rebounding) motion path with vehicles (Experiment 1) and furniture (Experiment 2). During the habituation phase, infants saw a dog jumping over a barrier and either a vehicle or a piece of furniture rebounding off the barrier. In the test phase, infants looked longer when another inanimate object jumped rather than rebounded, but showed no such differential looking in the case of another animate object. The ability to restrict the animate motion path of jumping to animate beings was present by 10 months of age. The present findings support the hypothesis that motion path is associated with the animate-inanimate distinction early in infancy., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Human embryonic stem cells (hESCs) are pluripotent and capable of generating new β-cells, but current in vitro differentiation protocols generally fail to produce mature, glucose-responsive, unihormonal β-cells. Instead, these methods tend to produce immature polyhormonal endocrine cells which mature in vivo into glucagon-positive α-cells. PAX4 is an established transcription factor in β-cell development and function, and is capable of converting glucagon-positive cells to insulin-positive cells in mice. Work in human and mouse ESCs has shown that constitutive PAX4 expression promotes the development of insulin-positive cells, but whether acute PAX4 expression is sufficient to guide specific endocrine cell fates has not been addressed in hESCs. In this study, we applied recombinant adenovirus to ectopically express human PAX4 in hESC-derived pancreatic progenitors, with the aim of influencing the endocrine developmental cascade away from polyhormonal cells toward unihormonal insulin-positive cells. Gene delivery to pancreatic progenitors was efficient and dose-dependent. By the end of in vitro differentiation, PAX4 reduced ARX expression, but only the high dose tested significantly reduced glucagon release. Single cell analysis revealed that while PAX4 did not alter the proportion of endocrine cells, it did reduce the number of glucagon-positive cells and increased the number of unihormonal insulin-positive cells. These data suggest that acute PAX4 overexpression can reduce expression of ARX and glucagon resulting in improved numbers of unihormonal insulin-positive cells.

Lipotoxicity is implicated in pancreatic β-cell dysfunction in obesity-induced type 2 diabetes. In vitro, activation of peroxisome proliferator-activated receptor α (PPARα) has been shown to protect pancreatic β-cells from the lipotoxic effects of palmitate, thereby preserving insulin secretion. Utilizing an adeno-associated virus (dsAAV8), overexpression of PPARα was induced specifically in pancreatic β-cells of adult, C57Bl/6 mice fed a high-fat diet for 20 weeks and carbohydrate metabolism and β-cell mass assessed. We show that overexpression of PPARα in pancreatic β-cells in vivo preserves β-cell function in obesity, and this improves glucose tolerance by preserving insulin secretion in comparison to control mice with diet-induced obesity. No changes in β-cell mass were observed in PPARα-overexpressing mice compared with diet-induced obese control animals. This model of β-cell-specific PPARα overexpression provides a useful in vivo model for elucidating the mechanisms underlying β-cell lipotoxicity in obesity-induced type 2 diabetes.

Background: Certain sociodemographic subgroups of HIV-infected patients may experience more chronic disease than others due to behavioural risk factors, advanced HIV disease or complications from extended use of combination antiretroviral therapy (cART), but recent comparative data are limited., Methods: We studied HIV-infected adult patients in care during 2006-2010 who had been prescribed ≥ 6 months of cART. We analysed the prevalence of selected key chronic conditions and polymorbidity (having 2 or more out of 10 key conditions) by gender and race/ethnicity., Results: Of the 3,166 HIV-infected patients (median age 47 years, CD4⁺ T-cell count 496 cells/mm³, duration of cART use 6.8 years), 21% were female, 57% were non-Hispanic White and over half were current or former tobacco smokers. The five most frequent conditions among women (median age 45 years) were dyslipidaemia (67.3%), hypertension (57.4%), obesity (31.7%), viral hepatitis B or C coinfection (29.0%) and low high-density lipoprotein cholesterol (HDLc; 27.3%). The five most frequent conditions in men (median age 47 years) were dyslipidaemia (81.2%), hypertension (54.4%), low HDLc (41.1%), elevated triglycerides (32.3%) and elevated non-HDLc (26.8%). In multivariable analyses, Hispanic patients had higher prevalence of obesity and diabetes than White patients; Black patients had higher prevalence of obesity and hypertension but lower rates of lipid abnormalities. Of all patients, 73.7% of women and 66.8% of men had polymorbidity, with no evidence of disparities by race/ethnicity., Conclusions: Among contemporary cART-treated HIV-infected adults, chronic conditions and polymorbidity were common, underscoring the importance of chronic disease prevention and management among ageing HIV-infected patients.

Background. It is unclear if CD4 cell counts at HIV diagnosis have improved over a 10-year period of expanded HIV testing in the USA. Methods. We studied HOPS participants diagnosed with HIV infection ≤6 months prior to entry into care during 2000-2009. We assessed the correlates of CD4 count <200 cells/mm(3) at HIV diagnosis (late HIV diagnosis) by logistic regression. Results. Of 1,203 eligible patients, 936 (78%) had a CD4 count within 3 months after HIV diagnosis. Median CD4 count at HIV diagnosis was 299 cells/mm(3) and did not significantly improve over time (P = 0.13). Comparing periods 2000-2001 versus 2008-2009, respectively, 39% and 35% of patients had a late HIV diagnosis (P = 0.34). Independent correlates of late HIV diagnosis were having an HIV risk other than being MSM, age ≥35 years at diagnosis, and being of nonwhite race/ethnicity. Conclusions. There is need for routine universal HIV testing to reduce the frequency of late HIV diagnosis and increase opportunity for patient- and potentially population-level benefits associated with early antiretroviral treatment.

Objective: Understanding mortality differences among HIV-infected patients can focus efforts to improve survival., Design: We evaluated death rates, causes, and associated factors among treated patients in the HIV Outpatient Study (HOPS), a large, prospective, multicenter observational cohort of HIV-infected persons seen at a diverse set of US sites of care., Methods: Among 3754 HOPS participants seen during 1996-2007 with at least 6 months of follow-up after initiating HAART and receiving HAART at least 75% of time under observation ('substantially treated'), we calculated hazard ratios for death using proportional hazards regression models. We also examined death causes and comorbidities among decedents., Results: Substantially treated participants, followed a median 4.7 years (interquartile range, 2.2-8.5), experienced 331 deaths. In multivariable analyses, higher mortality was associated with an index CD4 cell count less than 200 cells/μl [adjusted hazard ratio (aHR), 2.86; 95% confidence interval (CI) 1.95-4.21], older age (aHR, 1.50 per 10 years; 95% CI 1.33-1.70), log(10)HIV RNA (aHR, 1.67 per log(10); 95% CI 1.51-1.85), but not race/ethnicity (aHR, 0.99 for blacks vs. whites, P = 0.92). Mortality was increased among publicly insured (PUB) vs. privately insured participants (PRV) when index CD4 cell count was at least 200 cells/μl (aHR, 2.03; 95% CI 1.32-3.14) but not when index CD4 cell count was less than 200 cells/μl (aHR, 1.3, P = 0.13). By death cause, PUB had significantly more cardiovascular events and hepatic disorders than PRV. Comorbidities more frequent among PUB vs. PRV decedents included cardiovascular disease, renal impairment, and chronic hepatitis., Conclusion: Among HAART-treated participants with CD4 cell counts at least 200 cells/μl, PUB experienced higher death rates than PRV. Non-AIDS death and disease causes predominated among publicly insured decedents, suggesting that treatable comorbidities contributed to survival disparities.

We explored common reasons for non-use of the rapidly growing popularity of social networking sites among a sample of Australian adolescents (N = 69). Transcripts were coded by grouping responses along similar themes for non-use that had been commonly stated by participants. The primary reasons offered by adolescents were: lack of motivation, poor use of time, preference for other forms of communication, preference for engaging in other activities, cybersafety concerns, and a dislike of self-presentation online. The identification of these themes allows for a greater understanding of teenagers' decisions not to engage in the popular medium of communication and points to possible strategies that could be utilised by Web site developers in efforts to appeal to a wider teenage audience.

Islet transplantation represents a potential cure for type 1 diabetes; however, a lack of sufficient donor material limits its clinical use. To address the shortfall of islet availability, surrogate insulin-producing cells are sought. Studies suggest that human amniotic fluid (hAF) contains multipotent progenitor cells capable of differentiating to all three germ layers. Here, we used high-content, live-cell imaging to assess the ability to reprogram hAF cells towards a beta cell phenotype. A fluorescent reporter system was developed where DsRed express (DSRE) expression is driven by the human insulin promoter. Using integrative lentiviral technology, we created stable reporter hAF cells that could be routinely monitored for insulin promoter activation. These cells were subjected to combinatorial high-content screening using adenoviral-mediated expression of up to six transcription factors important for beta cell development. Cells were monitored for DSRE expression which revealed an optimal combination of the transcription factors required to induce insulin gene expression in hAF cells. These optimally induced cells were examined for expression of additional beta cell transcription factors and proteins involved in glucose sensing and insulin processing. RT-qPCR revealed very low level expression of insulin that was ultimately insufficient to reverse streptozotocin-induced diabetes following sub-capsular kidney transplantation. High-content, live-cell imaging using fluorescent reporter cells provides a convenient method for repeated assessment of cellular reprogramming. hAF cells could be reprogrammed to express key beta cell proteins, however insulin gene expression was insufficient to reverse hyperglycemia in diabetic animals., (Copyright © 2010 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.)

DNA methylation is an important epigenetic modification involved in transcriptional regulation, nuclear organization, development, aging, and disease. Although DNA methyltransferases have been characterized, the mechanisms for DNA demethylation remain poorly understood. Using a cell-based reporter assay, we performed a functional genomics screen to identify genes involved in DNA demethylation. Here we show that RNF4 (RING finger protein 4), a SUMO-dependent ubiquitin E3-ligase previously implicated in maintaining genome stability, plays a key role in active DNA demethylation. RNF4 reactivates methylation-silenced reporters and promotes global DNA demethylation. Rnf4 deficiency is embryonic lethal with higher levels of methylation in genomic DNA. Mechanistic studies show that RNF4 interacts with and requires the base excision repair enzymes TDG and APE1 for active demethylation. This activity appears to occur by enhancing the enzymatic activities that repair DNA G:T mismatches generated from methylcytosine deamination. Collectively, our study reveals a unique function for RNF4, which may serve as a direct link between epigenetic DNA demethylation and DNA repair in mammalian cells.

Objectives: To assess the incidence and spectrum of AIDS-defining opportunistic illnesses in the highly active antiretroviral therapy (cART) era., Design: A prospective cohort study of 8070 participants in the HIV Outpatient Study at 12 U.S. HIV clinics., Methods: We calculated incidence rates per 1000 person-years of observation for the first opportunistic infection, first opportunistic malignancy, and first occurrence of each individual opportunistic illness during 1994-2007. Using stratified Poisson regression models, and adjusting for sex, race, and HIV risk category, we modeled annual percentage changes in opportunistic illness incidence rates by calendar period., Results: Eight thousand and seventy patients (baseline median age 38 years; median CD4 cell count 298 cells/microl) experienced 2027 incident opportunistic illnesses during a median of 2.9 years of observation. During 1994-1997, 1998-2002, and 2003-2007, respectively, rates of opportunistic infections (per 1000 person-years) were 89.0, 25.2 and 13.3 and rates of opportunistic malignancies were 23.4, 5.8 and 3.0 (P for trend <0.001 for both). Opportunistic illness rate decreases were similar for the subset of patients receiving cART. During 2003-2007, there were no significant changes in annual rates of opportunistic infections or opportunistic malignancies; the leading opportunistic illnesses (rate per 1000 person-years) were esophageal candidiasis (5.2), Pneumocystis pneumonia (3.9), cervical cancer (3.5), Mycobacterium avium complex infection (2.5), and cytomegalovirus disease (1.8); 36% opportunistic illness events occurred at CD4 cell counts at least 200 cells/microl., Conclusions: Opportunistic illness rates declined precipitously after introduction of cART and stabilized at low levels during 2003-2007. In this contemporary cART era, a third of opportunistic illnesses were diagnosed at CD4 cell counts at least 200 cells/microl.

Introduction: Monitoring antiretroviral (ARV) drug resistance is of growing importance in the management of persons infected with HIV, but few reports document how genotypic and phenotypic resistance testing (GPT) has been used among patients receiving routine outpatient care., Methods: We studied data from participants in the HIV Outpatient Study seen at 10 HIV clinics in the United States during 1999 to 2006. We restricted analyses to patients whom we considered eligible for GPT (i.e., had a documented HIV viral load >1000 copies/mL). We used multivariable general modeling to evaluate temporal trends in use of GPT among eligible patients and to identify factors associated with being tested during 1999 to 2002 and 2003 to 2006., Results: Of 5594 active patients, 3995 (71%) were considered eligible for GPT in at least one year during 1999 to 2006 (declining from 50.2% in 1999 to 31.2% in 2006). The fraction of eligible patients receiving GPT increased from 11.2% in 1999 to 31.0% in 2003 (P < 0.001 for trend) and then stabilized at approximately 30% through 2006. Among persons tested, the annual percentage receiving only genotype testing declined over time (90% to 56%), whereas the percentage receiving genotype and phenotype testing increased (5.4% to 39.1%). The annual use of GPT for ARV-naïve patients increased over time and after 2003 exceeded the corresponding rates for ARV-experienced patients. In multivariable analyses, low CD4 count and high HIV viral load were consistently associated with GPT. Compared with other ARV-experienced patients, those who were triple ARV-class experienced were consistently more likely to be tested, whereas ARV-naïve were less likely to be tested during 1999 to 2002 and more likely during 2003 to 2006. In addition, women and heterosexual men (vs. men who have sex with men) and black patients (vs. white) were less likely to be tested during 1999 to 2002, whereas older patients were less likely to be tested during 2003 to 2006., Discussion: The annual frequency of GPT use has increased almost threefold since 1999. GPT use among ARV-naïve patients has increased coincident with dissemination of recommendations. Although earlier sex and racial/ethnic disparities in testing have waned, older patients were significantly less likely to be tested in recent years.

Integrins are heterodimeric receptors composed of alpha and beta transmembrane subunits that mediate attachment of cells to the extracellular matrix and counter-ligands such as ICAM-1 on adjacent cells. beta2 integrin (CD18) associates with four different alpha (CD11) subunits to form an integrin subfamily, which has been reported to be expressed exclusively on leukocytes. However, recent studies indicate that beta2 integrin is also expressed by other types of cells. Since the gene for beta2 integrin is located in the region of human chromosome 21 associated with congenital heart defects, we postulated that it may be expressed in the developing heart. Here, we show the results from several different techniques used to test this hypothesis. PCR analyses indicated that beta2 integrin and the alphaL, alphaM, and alphaX subunits are expressed during heart development. Immunohistochemical studies in both embryonic mouse and chicken hearts, using antibodies directed against the N- or C-terminal of beta2 integrin or against its alpha subunit partners, showed that beta2 integrin, as well as the alphaL, alphaM, and alphaX subunits, are expressed by the endothelial and mesenchymal cells of the atrioventricular canal and in the epicardium and myocardium during cardiogenesis. In situ hybridization studies further confirmed the presence of beta2 integrin in these various locations in the embryonic heart. These results indicate that the beta2 integrin subfamily may have other activities in addition to leukocyte adhesion, such as modulating the migration and differentiation of cells during the morphogenesis of the cardiac valves and myocardial walls of the heart.

Background: Healthcare claims data were used to better understand the diagnostic investigation and treatment of cancer., Material/methods: A retrospective cohort study was used involving claims data from a large insurance company. Analyses were based on electronic claims data from 1997 through 2006 for enrollees aged 15-64 years., Results: This study showed that 96% of all first time cancer-related claims involved physician services. The percentage of physician services involving diagnostic workup in the form of some combination of blood testing, radiology, and surgery was 89% for non-skin cancer and 95% for skin cancer. The percentage of physician services involving some combination of chemotherapy, radiation, and surgery was 24% for non-skin cancer and 14% for skin cancer. Thus, for cancer (excluding skin cancer) the ratio of diagnostic workup to treatment was 2.7 to 1. For skin cancer, the ratio was 6.3 to 1. The percentage receiving treatment ranged from 13% for the male genital system to 46% for cancers of the bones and joints. Beyond cancers of the male or female genital systems, cancer-related claims involving treatment were 34% (95% CI 17-54%) higher for females than males., Conclusions: Healthcare claims data can be used to generate useful information for physicians and their patients about the process and nature of the diagnostic workups and treatment that typically occur when cancer is suspected.

Purpose: This study describes the influence of attention deficit hyperactivity disorder (ADHD) on the incidence rates of selected injuries., Methods: A retrospective cohort study design was employed using medical claims data from the Deseret Mutual Benefit Administrators (DMBA), a health insurance company for employees of the Church of Jesus Christ of Latter-day Saints (LDS) and their spouses and dependent children. ADHD diagnosis, injury, medication, and demographic data were extracted from claims files during 1998-2005 for all enrollees aged 0-64 years., Results: Incidence rates of ADHD were 1.83 (95% CI 1.68-2.00) times greater in males than females and highest in the age group 5-9 years and income group $80,000 or greater. ADHD increased the risk of selected injuries. The most common injuries involved sprains and strains of joints, then open wounds of the head, neck and trunk, and upper/lower limb, and then fractures of the upper/lower limb. Medication did not significantly protect against injury in ADHD patients. The rate of severe injury (i.e., fracture of skull, neck and trunk; intracranial injury excluding those with skull fracture; and injuries to nerves and spinal cord) was 3.07 (95% CI 2.37-3.98) times more common in ADHD enrollees compared with non-ADHD enrollees. Those with 1, 2, 3, or 4 or more injuries were 1.67 (1.50-1.86), 2.11 (1.75-2.56), 2.63 (1.80-3.84), and 2.94 (1.47-5.87) times more likely to have ADHD, respectively., Conclusions: ADHD is positively associated with injuries. More severe injuries have a significantly stronger associated with ADHD than less severe injuries.

Objectives: To assess temporal trends in the rates of hospitalizations and associated diagnoses among HIV-infected patients before and during the era of highly active antiretroviral therapy., Design: A prospective cohort study of 7155 patients enrolled in the HIV Outpatient Study at 10 US HIV clinics., Methods: We evaluated rates of hospitalizations for major categories of medical conditions during 1994-2005 and modeled trends in these rates using multivariable Poisson regression models for repeated observations. We assessed patient characteristics associated with hospitalization using multiple logistic regression., Results: The rates of hospitalizations (per 100 person-years) fell from 24.6 in 1994 to 11.8 in 2005 (P < 0.0001). The rates of hospitalizations for AIDS opportunistic infections decreased from 7.6 in 1994-1996 to 1.0 in 2003-2005 (P < 0.0001). AIDS opportunistic infections were present at 31% of hospitalizations in 1994-1996 versus 9.5% in 2003-2005, and chronic end-organ disease conditions were present at 7.2% of such hospitalizations in 1994-1996 versus 14.3% in 2003-2005. Mean CD4+ cell count at hospitalization increased from 115 cells/mul in 1994 to 310 cells/mul in 2005. Factors independently associated with hospitalization in the highly active antiretroviral therapy era (1997-2005) included older age, history of substance abuse, lower CD4+ cell count, history of AIDS, and public health insurance., Conclusion: The rates of hospitalizations for HIV-infected patients declined substantially during 1994-2005, due mainly to reductions in the AIDS opportunistic infections. Compared with the period 1994-1997, patients in the highly active antiretroviral therapy era were hospitalized with higher CD4+ cell counts and more frequently for chronic end-organ conditions.

Background: AIDS-related death and disease rates have declined in the highly active antiretroviral therapy (HAART) era and remain low; however, current causes of death in HAART-treated patients remain ill defined., Objective: To describe mortality trends and causes of death among HIV-infected patients in the HAART era., Design: Prospective, multicenter, observational cohort study of participants in the HIV Outpatient Study who were treated from January 1996 through December 2004., Measurements: Rates of death, opportunistic disease, and other non-AIDS-defining illnesses (NADIs) determined to be primary or secondary causes of death., Results: Among 6945 HIV-infected patients followed for a median of 39.2 months, death rates fell from 7.0 deaths/100 person-years of observation in 1996 to 1.3 deaths/100 person-years in 2004 (P=0.008 for trend). Deaths that included AIDS-related causes decreased from 3.79/100 person-years in 1996 to 0.32/100 person-years in 2004 (P=0.008). Proportional increases in deaths involving liver disease, bacteremia/sepsis, gastrointestinal disease, non-AIDS malignancies, and renal disease also occurred (P=or<0.001, 0.017, 0.006, <0.001, and 0.037, respectively.) Hepatic disease was the only reported cause of death for which absolute rates increased over time, albeit not significantly, from 0.09/100 person-years in 1996 to 0.16/100 person-years in 2004 (P=0.10). The percentage of deaths due exclusively to NADI rose from 13.1% in 1996 to 42.5% in 2004 (P<0.001 for trend), the most frequent of which were cardiovascular, hepatic, and pulmonary disease, and non-AIDS malignancies in 2004. Mean CD4 cell counts closest to death (n=486 deaths) increased from 59 cells/microL in 1996 to 287 cells/microL in 2004 (P<0.001 for trend). Patients dying of NADI causes were more HAART experienced and initiated HAART at higher CD4 cell counts than those who died with AIDS (34.5% vs 16.8%, respectively, received HAART for 4 of more years, P<0.0001; 22.4% vs 7.8%, respectively, initiated HAART with CD4 cell counts of more than 350 cells/microL, P<0.001)., Conclusions: Although overall death rates remained low through 2004, the proportion of deaths attributable to non-AIDS diseases increased and prominently included hepatic, cardiovascular, and pulmonary diseases, as well as non-AIDS malignancies. Longer time spent receiving HAART and higher CD4 cell counts at HAART initiation were associated with death from non-AIDS causes. CD4 cell count at time of death increased over time.

Background: Body mass index (BMI) can influence drug metabolism, thus affecting efficacy and risk for toxicities. Hypothesizing that persons with an increased BMI and larger volumes of distribution may experience a suboptimal response to highly active antiretroviral therapy (HAART), we evaluated the effect of BMI on virologic and immunologic response in previously ART-naive patients initiating therapy., Methods: Using data from the HIV Outpatient Study, we analyzed the statistical association of BMI and other selected demographic variables with achieving an undetectable viral load and experiencing a CD4 cell count increase of more than 100 cell/microL after 3 to 9 months of therapy among antiretroviral-naive patients initiating HAART., Results: Among 711 patients included in analysis, 43% had a BMI of more than 25 (overweight-obese). Higher BMI was associated with being female, having black or Hispanic race/ethnicity, being heterosexual, and using injection drugs (all P<0.001). The patients in BMI groups did not differ significantly by baseline CD4 cell count or the duration of the initial HAART regimen. Although median baseline viral loads were significantly lower in obese participants (P=0.008), overweight or obese BMI did not significantly alter the likelihood of achieving an undetectable viral load and a CD4 cell count increase of more than 100 cells/microL compared with normal weight persons., Conclusion: A substantial proportion of HIV-infected outpatients in this cohort were overweight or obese. Increased BMI was not associated with decreased virologic and immunologic responses to initial HAART. Responses were equivalent and within expected ranges between normal weight patients, overweight patients, and obese patients at 3 to 9 months of observation.