A scalable solution for tumor mutational burden from formalin-fixed, paraffin-embedded samples using the Oncomine Tumor Mutation Load Assay.

BACKGROUND: Tumor mutational burden (TMB) is an increasingly important biomarker for immune checkpoint inhibitors. Recent publications have described strong association between high TMB and objective response to mono- and combination immunotherapies in several cancer types. Existing methods to estimate TMB require large amount of input DNA, which may not always be available. METHODS: In this study, we develop a method to estimate TMB using the Oncomine Tumor Mutation Load (TML) Assay with 20 ng of DNA, and we characterize the performance of this method on various formalin-fixed, paraffin-embedded (FFPE) research samples of several cancer types. We measure the analytical performance of TML workflow through comparison with control samples with known truth, and we compare performance with an orthogonal method which uses matched normal sample to remove germline variants. We perform whole exome sequencing (WES) on a batch of FFPE samples and compare the WES TMB values with TMB estimates by the TML assay. RESULTS: In-silico analyses demonstrated the Oncomine TML panel has sufficient genomic coverage to estimate somatic mutations with a strong correlation (r2=0.986) to WES. Further, in silico prediction using WES data from three separate cohorts and comparing with a subset of the WES overlapping with the TML panel, confirmed the ability to stratify responders and non-responders to immune checkpoint inhibitors with high statistical significance. We found the rate of somatic mutations with the TML assay on cell lines and control samples were similar to the known truth. We verified the performance of germline filtering using only a tumor sample in comparison to a matched tumor-normal experimental design to remove germline variants. We compared TMB estimates by the TML assay with that from WES on a batch of FFPE research samples and found high correlation (r2=0.83). We found biologically interesting tumorigenesis signatures on FFPE research samples of colorectal cancer (CRC), lung, and melanoma origin. Further, we assessed TMB on a cohort of FFPE research samples including lung, colon, and melanoma tumors to discover the biologically relevant range of TMB values. CONCLUSIONS: These results show that the TML assay targeting a 1.7-Mb genomic footprint can accurately predict TMB values that are comparable to the WES. The TML assay workflow incorporates a simple workflow using the Ion GeneStudio S5 System. Further, the AmpliSeq chemistry allows the use of low input DNA to estimate mutational burden from FFPE samples. This TMB assay enables scalable, robust research into immuno-oncology biomarkers with scarce samples.

Validation of the virtual-reality prospective memory test (Hong Kong Chinese version) for individuals with first-episode schizophrenia.

This study was performed to examine the psychometric properties of a Virtual-Reality Prospective Memory Test (Hong Kong Chinese version; VRPMT-CV). The VRPMT was administered to 44 individuals with first-episode schizophrenia. The test was administered again 2 weeks later to establish test-retest reliability. The concurrent validity of the VRPMT was evaluated by examining the correlations between the VRPMT score and the score on the Chinese version of the Cambridge Prospective Memory Test (CAMPROMPT-CV). The performance of individuals with schizophrenia on the VRPMT was also compared with that of 42 healthy control subjects to examine the test's sensitivity and specificity. The intraclass correlation for test-retest reliability of the total VRPMT-CV score was 0.78 (p = .005). A significant correlation was found between the total VRPMT-CV score and the total CAMPROMPT-CV score (r = 0.90; p < .001). Comparison with the healthy control subjects revealed that the total VRPMT-CV score was a sensitive (92.9%) and specific (75%) measure of prospective memory deficits in individuals with schizophrenia. The VRPMT-CV is an assessment of prospective memory that has good construct validity, test-retest reliability, sensitivity and specificity in the context of first-episode schizophrenia.

Culture adaptation alters transcriptional hierarchies among single human embryonic stem cells reflecting altered patterns of differentiation.

We have used single cell transcriptome analysis to re-examine the substates of early passage, karyotypically Normal, and late passage, karyotypically Abnormal ('Culture Adapted') human embryonic stem cells characterized by differential expression of the cell surface marker antigen, SSEA3. The results confirmed that culture adaptation is associated with alterations to the dynamics of the SSEA3(+) and SSEA3(-) substates of these cells, with SSEA3(-) Adapted cells remaining within the stem cell compartment whereas the SSEA3(-) Normal cells appear to have differentiated. However, the single cell data reveal that these substates are characterized by further heterogeneity that changes on culture adaptation. Notably the Adapted population includes cells with a transcriptome substate suggestive of a shift to a more naïve-like phenotype in contrast to the cells of the Normal population. Further, a subset of the Normal SSEA3(+) cells expresses genes typical of endoderm differentiation, despite also expressing the undifferentiated stem cell genes, POU5F1 (OCT4) and NANOG, whereas such apparently lineage-primed cells are absent from the Adapted population. These results suggest that the selective growth advantage gained by genetically variant, culture adapted human embryonic stem cells may derive in part from a changed substate structure that influences their propensity for differentiation.

Using social determinants of health to link health workforce diversity, care quality and access, and health disparities to achieve health equity in nursing.

It is widely accepted that diversifying the nation's health-care workforce is a necessary strategy to increase access to quality health care for all populations, reduce health disparities, and achieve health equity. In this article, we present a conceptual model that utilizes the social determinants of health framework to link nursing workforce diversity and care quality and access to two critical population health indicators-health disparities and health equity. Our proposed model suggests that a diverse nursing workforce can provide increased access to quality health care and health resources for all populations, and is a necessary precursor to reduce health disparities and achieve health equity. With this conceptual model as a foundation, we aim to stimulate the conceptual and analytical work-both within and outside the nursing field-that is necessary to answer these important but largely unanswered questions.

The effect of hemorrhage on the development of the postnatal mouse cerebellum.

Recent studies have shown that hemorrhagic injury in the preterm cerebellum leads to long-term neurological sequelae, such as motor, affective, and cognitive dysfunction. How cerebellar hemorrhage (CBH) affects the development and function of the cerebellum is largely unknown. Our study focuses on developing a mouse model of CBH to determine the anatomical, behavioral, and molecular phenotypes resulting from a hemorrhagic insult to the developing cerebellum. To induce CBH in the postnatal mouse cerebellum, we injected bacterial collagenase, which breaks down surrounding blood vessel walls, into the fourth ventricle at postnatal day two. We found a reduction in cerebellar size during postnatal growth, a decrease in granule cells, and persistent neurobehavioural abnormalities similar to abnormalities reported in preterm infants with CBH. We further investigated the molecular pathways that may be perturbed due to postnatal CBH and found a significant upregulation of genes in the inflammatory and sonic hedgehog pathway. These results point to an activation of endogenous mechanisms of injury and neuroprotection in response to postnatal CBH. Our study provides a preclinical model of CBH that may be used to understand the pathophysiology of preterm CBH and for potential development of preventive therapies and treatments.

TaqMan® OpenArray® high-throughput transcriptional analysis of human embryonic and induced pluripotent stem cells.

It is widely accepted that somatic cells can be reprogrammed by a set of transcription factors to become embryonic stem cell-like: These reprogrammed cells, induced pluripotent stem cells (iPSCs), are nearly identical to embryonic stem cells (ESCs), because both have the capacity to self-renew and to form all cellular lineages of the body. Transcriptional differences between ESCs, iPSCs, and fibroblasts can be analyzed by quantitative PCR (qPCR) using TaqMan(®) Gene Expression assays, a widely used tool for rapid analysis of different cell types. In this chapter, we describe the OpenArray(®) platform which generates qPCR data from high-throughput instrumentation. We examined the gene signature profiles of ESCs, fibroblasts, and iPSCs with a TaqMan(®) OpenArray(®) Human Stem Cell Panel containing 631 TaqMan(®) Gene Expression assays that represent pathways involved in self-renewal, pluripotency, lineage patterning, transcriptional networks, stem cell differentiation, and development.

The expression of HDAC1 and HDAC2 during cerebellar cortical development.

Histone deacetylases (HDACs) are epigenetic regulatory proteins that repress gene transcription by changing DNA conformation. The regulation of gene expression through histone deacetylation is an important mechanism for the development of the central nervous system. Although the disruption of the balance in epigenetic gene regulation has been implicated in many CNS developmental abnormalities and diseases, the expression pattern of HDACs in various cell types in the brain during its maturation process has had limited exploration. Therefore, in this study, we investigate the cell type-specific and developmental stage-specific expression pattern of HDAC1 and HDAC2 in the mouse cerebellum. Our experimental results show that the cerebellar progenitors and glial cells express high levels of HDAC1 and low levels of HDAC2. On the other hand, the post-mitotic migrating neuronal cells of the cerebellar cortex show strong HDAC2 and weak HDAC1 expressions. In more differentiated neuronal cells, including Purkinje cells, granule cells, unipolar brush cells, and GABAergic interneurons, we found a consistent expression pattern, high levels of HDAC2 and low levels of HDAC1. Therefore, our data provide support for the potential important roles of HDAC1 in cell proliferation and HDAC2 in migration and differentiation.

Blinded randomised controlled study of the effect of a discharge communication template on proton pump inhibitor prescribing.

AIM: To evaluate whether the inclusion of advice in the hospital discharge letter regarding published guidelines for the review of PPI therapy can increase the number of patients that have documented PPI therapy review, consistent with the published guidelines, following hospital discharge. METHOD: Patients on PPIs at discharge from hospital were randomised to either have their hospital discharge letter completed as per usual practice or to have additional information on PPI review included that was aligned to published local guidelines. Patients' GP records were reviewed at 3 to 6 months post discharge to determine if a PPI review had occurred and if that review adhered to the guidelines. RESULTS: Including specific, guideline based, PPI discharge instructions in the hospital discharge summary did not significantly increase the number of patients receiving post-discharge review consistent with the guidelines. Post discharge only 5/26 (19%) patients in the control group and 6/25 (24%) in the intervention group had their PPI therapy reviewed in accordance with the guidelines. CONCLUSION: We were not able to demonstrate a beneficial change in PPI prescribing practice from the inclusion of PPI prescribing advice in the discharge letter.

TaqMan Array Cards in pharmaceutical research.

TaqMan Array Cards are high-throughput, accurate, sensitive, and simple-to-use tools for quantitative analysis of mRNA or miRNA transcripts using a real-time PCR protocol. They utilize a microfluidic card with 384 reaction chambers and eight sample loading ports. For studies of coding transcripts, the reaction chambers are preloaded with user selected or predefined panels of Applied Biosystems TaqMan Gene Expression Assays. These assays enable real-time monitoring of a PCR reaction via hydrolysis of an oligonucleotide probe which has been dual labeled with fluorescent dye and quencher. Applications of TaqMan Array Cards include verification and follow on testing of microarray results, as well as hypothesis driven testing of panels of genes selected for their biological functions and relationships. This chapter describes a protocol for assaying transcription in cultured cells using methods optimized to minimize hands-on time and pipetting steps by skipping RNA isolation and generating cDNA directly in Ambion Cells-to-C(T) lysis solution.

Age expansion of the thirty-second walk test norms for children.

PURPOSE: The purposes of this study were to expand age ranges for a previously published normative database (n = 227) on the 30-second walk test, describe changes with age, explore contributions of subject characteristics, and verify previous data. METHODS: Children (n = 302; age, 5-17 years) from 4 urban schools were tested for distance walked in 30 seconds. Age, height, right lower extremity length, weight, sex, and race/ethnicity were recorded. RESULTS: Distance walked increased from 5 to 10 years of age, decreased slightly at age 11 years, followed by a more gradual decrease from 12 to 17 years. A significant difference in distance walked was found across ages. Right leg length, age, and weight explained 11.5% of the variance in walk distance. CONCLUSION: A percentile chart of the pooled data (previous and current, n = 529) should facilitate the use of the 30-second walk test when examining children for mobility limitations.

MicroRNAs in embryonic stem cells.

The unique properties of embryonic stem cells (ESCs) to self-renew indefinitely or to differentiate to any cell type have great potential for clinical applications in regenerative medicine. MicroRNAs (miRNAs) are emerging as important regulators of post-transcriptional gene expression and have been implicated as crucial elements in regulating ESCs. Here, we review recent progresses in characterizing the role of miRNAs in the maintenance and development of ESCs.

Leptin replacement therapy modulates circulating lymphocyte subsets and cytokine responsiveness in severe lipodystrophy.

CONTEXT: We conducted this study to understand the role of leptin therapy in immunomodulation. OBJECTIVE: Our objective was to study lymphocyte subpopulations and in vitro peripheral blood mononuclear cell (PBMC) activation during a study evaluating the effects of leptin on metabolic functions in severe lipodystrophy (serum leptin levels < 4 ng/ml). DESIGN AND SETTING: We conducted an open-label study with patients serving as their own control at the Clinical Research Center of the National Institutes of Health. PATIENTS: Ten patients (age range, 15-63 yr; one male and nine females) with generalized forms of lipodystrophy were studied. INTERVENTION: Patients were treated with recombinant human leptin to achieve high normal concentrations for 4 to 8 months. RESULTS: Leptin levels increased from 1.8 +/- 0.4 to 16.5 +/- 3.9 ng/dl (P < 0.001), whereas metabolic control improved [glycosylated hemoglobin (HbA(1c)) fell from 9.3 +/- 0.4 to 7.1 +/- 1.4%, P < 0.001, and triglycerides decreased by 45 +/- 11% from a mean of 1490 +/- 710 mg/dl, P = 0.001]. Lymphocyte subsets were studied by flow cytometry at baseline and at 4 and 8 months of therapy. PBMC responsiveness was evaluated by cytokine release and proliferation after stimulation with phytohemagglutinin, phytohemagglutinin plus IL-12, lipopolysaccharide, and lipopolysaccharide plus interferon-gamma at baseline and 4 months. Various T lymphocyte subsets were significantly lower than age- and sex-matched controls at baseline; however, the CD4/CD8 ratio was normal. The relative percentages of B lymphocytes and monocytes were elevated, although the absolute levels were normal. Leptin therapy induced significant changes in T lymphocyte subsets, which normalized both the absolute number of T lymphocyte subsets and relative percentages of all lineages. Additionally, in vitro TNF-alpha secreted from PBMC of patients was significantly increased to normal after 4 months of leptin therapy compared with baseline. CONCLUSION: These data support existing evidence that leptin has a modest immunomodulatory effect in hypoleptinemic humans.

The effect of heel-pad thickness and loading protocol on measured heel-pad stiffness and a standardized protocol for inter-subject comparability.

BACKGROUND: Heel-pad stiffness is an important parameter in clinical assessments of the lower limb and is usually quantified by the slope of the force-deformation curve. However, the data produced is affected by the geometry of the heel, thus making inferences about tissue behaviour difficult. METHOD: With the use of finite element analysis the aim of this study is to explore the possibility of expressing heel-pad stiffness in terms of stress-strain data. An axisymmetric, non-linear and time-dependent representation of the heel was created. The material model, incorporating non-linearity and viscoelasticity, was based on a series of experiments involving healthy, cadaveric specimens and loading at different loading rates (0, 175 and 350 mm/s). The conditions of an in vivo study were then replicated and stress-strain data of the model were compared. Good agreement was achieved (error <5%) at higher strains (>0.2). Probe diameter, loading rate and heel-pad thickness were then varied and heel-pad stiffness, expressed in terms of both force-deformation and stress-strain characteristics, reported. FINDINGS: In terms of the force-deformation characteristics, thin heels are consistently stiffer than thick heels. In terms of stress-strain characteristics, thicker heels are stiffer than thin heels using small probes whereas thinner heels are stiffer than thick heels using large probes. It was possible to predict stress-strain data of the heel-pad that are least-dependent of heel-pad thickness using large probes and slow-rising loads. INTERPRETATION: It is suggested that stress-strain curves derived from large probes under slow loads would provide the most robust and standardized measure of heel-pad stiffness.

Phytochemical phenolics in organically grown vegetables.

Fruit and vegetable intake is inversely correlated with risks for several chronic diseases in humans. Phytochemicals, and in particular, phenolic compounds, present in plant foods may be partly responsible for these health benefits through a variety of mechanisms. Since environmental factors play a role in a plant's production of secondary metabolites, it was hypothesized that an organic agricultural production system would increase phenolic levels. Cultivars of leaf lettuce, collards, and pac choi were grown either on organically certified plots or on adjacent conventional plots. Nine prominent phenolic agents were quantified by HPLC, including phenolic acids (e. g. caffeic acid and gallic acid) and aglycone or glycoside flavonoids (e. g. apigenin, kaempferol, luteolin, and quercetin). Statistically, we did not find significant higher levels of phenolic agents in lettuce and collard samples grown organically. The total phenolic content of organic pac choi samples as measured by the Folin-Ciocalteu assay, however, was significantly higher than conventional samples (p < 0.01), and seemed to be associated with a greater attack the plants in organic plots by flea beetles. These results indicated that although organic production method alone did not enhance biosynthesis of phytochemicals in lettuce and collards, the organic system provided an increased opportunity for insect attack, resulting in a higher level of total phenolic agents in pac choi.

Long-term efficacy of leptin replacement in patients with generalized lipodystrophy.

Ectopic fat accumulation has been implicated as a contributing factor in the abnormal metabolic state of obesity. One human model of ectopic fat deposition is generalized lipodystrophy. Generalized lipodystrophy is a rare disorder characterized by a profound deficiency of adipose tissue with resultant loss of triglyceride storage capacity and reduced adipokines, including leptin. Subjects with generalized lipodystrophy and reduced leptin levels often have an increased appetite leading to hyperphagia. Excess fuel consumption, coupled with a lack of adipose tissue, contributes to the significant ectopic triglyceride accumulation in the muscle and liver seen in these subjects. This ectopic fat, along with the deficiency in leptin signaling and perhaps other adipokines, likely contributes to insulin resistance, diabetes, and hepatic steatosis. We report here the long-term effects of leptin replacement in a cohort of these subjects. Fifteen patients with generalized lipodystrophy were treated with twice-daily recombinant methionyl human leptin (r-metHuLeptin) for 12 months. We evaluated metabolic parameters at baseline and every 4 months. Antidiabetes medications were decreased or discontinued as necessary. Reductions were seen in serum fasting glucose (from 205 +/- 19 to 126 +/- 11 mg/dl; P < 0.001), HbA1c (from 9 +/- 0.4 to 7.1 +/- 0.5%; P < 0.001), triglycerides (from 1,380 +/- 500 to 516 +/- 236 mg/dl; P < 0.001), LDL (from 139 +/- 16 to 85 +/- 7 mg/dl; P < 0.01), and total cholesterol (from 284 +/- 40 to 167 +/- 21 mg/dl; P < 0.01). HDL was unchanged (from 31 +/- 3 to 29 +/- 2 mg/dl; P = 0.9). Liver volumes were significantly reduced (from 3,663 +/- 326 to 2,190 +/- 159 cm3; P < 0.001), representing loss of steatosis. Decreases were seen in total body weight (from 61.8 +/- 3.6 to 57.4 +/- 3.4 kg; P = 0.02) and resting energy expenditure (from 1,929 +/- 86 to 1,611 +/- 101 kcal/24 h; P < 0.001). R-metHuLeptin led to significant and sustained improvements in glycemia, dyslipidemia, and hepatic steatosis. Leptin represents the first novel, effective, long-term treatment for severe forms of lipodystrophy.

The effect of loading conditions on stress in the barefooted heel pad.

PURPOSE: High internal stress is considered to be a possible cause of heel-pad problems. External biomechanical measurements are used to attempt to understand the causes of heel pain. However, internal stress cannot be measured experimentally. Therefore, the purpose of this study was to quantify the relationship between magnitude of force, time to peak force, and sole angle with internal stresses in the heel using a finite element model. METHODS: Computer tomography (CT) was used to create a nonlinear time-dependent three-dimensional finite element model of the heel pad. The material model was based on previously reported force-displacement data derived from in vitro experiments. Although it was not possible to compare internal calculations of stress with experimental data, good agreement was found for external plantar pressures and strains when compared with in vivo values. Internal stresses and external plantar pressures were then investigated for different forces, loading rates (i.e., time to peak force), and angles of foot inclination in the sagittal plane (i.e., sole angle). RESULTS: The results of the model indicate that compressive stress is localized in the region inferior to the calcaneal tuberosity. Peak internal compressive stress was greater than external plantar pressure. Increasing the loading rate (i.e., reducing the time to peak force) caused plantar pressure to increase to a greater extent than internal stress. The general levels of stress were higher when the heel was loaded in an inclined position (i.e., greater sole angle). CONCLUSION: The finite element technique provides a useful step in bridging the gap between external measures and internal mechanics of the heel pad. A combined kinematic, kinetic, and modeling approach may be required when attempting to identify the biomechanical source of heel pain.

Clinical evidence that hyperinsulinaemia independent of gonadotropins stimulates ovarian growth.

OBJECTIVE: Ovarian enlargement is a constant feature of syndromes of extreme insulin resistance. The objective of this study is to show the role of insulin on ovarian growth in the presence of low gonadotropin levels. PATIENTS: Seven young patients with syndromes of extreme insulin resistance (five with lipodystrophy, one with Type B syndrome and one with Rabson-Mendenhall syndrome) were studied. MEASUREMENTS: Baseline LH concentrations and luteinizing hormone releasing hormone (LHRH) tests were performed. Total testosterone, insulin and C-peptide values were measured. Pelvic ultrasounds were performed. RESULTS: Four patients were prepubertal (age range 7-10 years old) and had prepubertal gonadotropin levels, and 2 of the 4 who were tested did not respond to LHRH (NIH 10 and RM-PAL). Three patients were Tanner stage 4 (age range 13-17 years old) and had low gonadotropins that did not respond to LHRH stimulation test. All seven patients had marked hyperinsulinaemia and 6 of 7 had at least one enlarged ovary. Testosterone values were increased in 4 of 7 patients. CONCLUSION: This represents the first example of the pathologic role of insulin to stimulate ovarian growth with low circulating gonadotropins. Thus, while ovarian growth and steroidogenesis are normally stimulated by gonadotropins at puberty, hyperinsulinaemia stimulates pathologic growth of the ovary and an androgenic steroid profile that is active at all ages. We suggest that these patients constitute a model to separate the effect of insulin from gonadotropin in stimulating ovarian growth and/or steroidogenesis.

The long-term effect of recombinant methionyl human leptin therapy on hyperandrogenism and menstrual function in female and pituitary function in male and female hypoleptinemic lipodystrophic patients.

Lipodystrophy patients are hypoleptinemic and insulin resistant. Women have enlarged polycystic ovaries, hyperandrogenism, and amenorrhea. We have determined the role of correction of hypoleptinemia on these metabolic and neuroendocrine parameters. Ten females and 4 males with generalized lipodystrophy were treated with recombinant methionyl human leptin (r-metHuLeptin) in physiologic doses in an open-labeled study for a period of 12 and 8 months, respectively. In the female group, serum free testosterone decreased from 39.6 +/- 11 to 18.9 +/- 4.5 ng/dL (P < 0.01) and serum sex hormone binding globulin increased from 14 +/- 2.5 to 25 +/- 4.8 nmol/L (P < 0.02). Luteinizing hormone (LH) responses to LH releasing hormone were more robust after therapy and significantly changed in the youngest group of 3 female patients (P < 0.01). Ovarian ultrasound showed a polycystic ovarian disease pattern in all patients and did not change after therapy. Eight of the 10 patients had amenorrhea prior to therapy and all 8 developed normal menses after therapy. In the male group, serum testosterone tended to increase from 433 +/- 110 to 725 +/- 184 ng/dL (P = 0.1) and sex hormone binding globulin also increased from 18.25 +/- 2.6 to 27 +/- 1.7 nmol/L (P < 0.04) following r-metHuLeptin therapy. Serum LH response to LH releasing hormone did not show significant changes. Five additional hypoleptinemic male subjects with minimal metabolic abnormalities underwent normal pubertal development without receiving r-metHuLeptin therapy. In both genders, insulin-like growth factor increased significantly and there were no differences in growth hormone, thyroid, or adrenal hormone levels following r-metHuLeptin therapy. Glycemic parameters significantly improved after r-metHuLeptin therapy in both groups. Hypoglycemic medications were discontinued in 7 of 12 patients and dramatically reduced in 5 patients. r-metHuLeptin therapy plays an important role in insulin sensitivity. In females, it plays an additional role in normalizing menstrual function. This is likely to occur both from increasing insulin sensitivity and from restoring LH pulsatility. The persistent hypoleptinemic state in these subjects did not inhibit pubertal development.

Proteinuric nephropathy in acquired and congenital generalized lipodystrophy: baseline characteristics and course during recombinant leptin therapy.

Generalized lipodystrophy is characterized by adipose tissue absence, hypoleptinemia, hypertriglyceridemia, insulin resistance, diabetes, hepatomegaly, and nonalcoholic steatohepatitis. In the course of recruiting patients for treatment with recombinant leptin, we were struck by the frequency and severity of proteinuria. We evaluated 25 patients with generalized lipodystrophy. Eighteen were treated with recombinant leptin, and we have followed 15 on leptin for 4-36 months. We followed renal parameters at baseline and during follow-up visits. Renal biopsies were performed as clinically indicated. At baseline, 22 of 25 patients (88%) had elevated urine albumin excretion (>30 mg/24 h), 15 (60%) had macroalbuminuria (>300 mg/24 h), and five (20%) had nephrotic-range proteinuria (>3500 mg/24 h). Twenty-three (92%) had elevated creatinine clearance (>125 ml/min.1.73 m(2)). Eleven of 15 patients (73%) treated with recombinant leptin exhibited reduction in proteinuria, associated with reduction of hyperfiltration. Four patients who did not improve are discussed individually. Renal biopsy findings were remarkable for focal segmental glomerulosclerosis in four patients, membranoproliferative glomerulonephritis in two patients, and diabetic nephropathy in one patient. In conclusion, generalized lipodystrophy is associated with proteinuria and unique renal pathologies, including focal segmental glomerulosclerosis and membranoproliferative glomerulonephritis. The majority treated with recombinant leptin demonstrated reduction in proteinuria and hyperfiltration.

Circular rapid amplification of cDNA ends for high-throughput extension cloning of partial genes.

The rapid amplification of cDNA ends (RACE) procedure is a widely used PCR-based method to clone the cDNA ends of mRNA transcripts. Current RACE methods often produce a high background of nonspecific PCR products, which can exclude the identification of the target cDNA of interest. We describe here an improved RACE procedure using circular cDNA templates and demonstrate the successful extension cloning of 4406 cDNAs.