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Publication
Journal: Nature
June/28/1993
Abstract
Multiple endocrine neoplasia type 2A (MEN 2A) is a dominantly inherited cancer syndrome that affects tissues derived from neural ectoderm. It is characterized by medullary thyroid carcinoma (MTC) and phaeochromocytoma. The MEN2A gene has recently been localized by a combination of genetic and physical mapping techniques to a 480-kilobase region in chromosome 10q11.2 (refs 2,3). The DNA segment encompasses the RET proto-oncogene, a receptor tyrosine kinase gene expressed in MTC and phaeochromocytoma and at lower levels in normal human thyroid. This suggested RET as a candidate for the MEN2A gene. We have identified missense mutations of the RET proto-oncogene in 20 of 23 apparently distinct MEN 2A families, but not in 23 normal controls. Further, 19 of these 20 mutations affect the same conserved cysteine residue at the boundary of the RET extracellular and transmembrane domains.
Publication
Journal: Science
January/22/2014
Abstract
Tumor recurrence is a leading cause of cancer mortality. Therapies for recurrent disease may fail, at least in part, because the genomic alterations driving the growth of recurrences are distinct from those in the initial tumor. To explore this hypothesis, we sequenced the exomes of 23 initial low-grade gliomas and recurrent tumors resected from the same patients. In 43% of cases, at least half of the mutations in the initial tumor were undetected at recurrence, including driver mutations in TP53, ATRX, SMARCA4, and BRAF; this suggests that recurrent tumors are often seeded by cells derived from the initial tumor at a very early stage of their evolution. Notably, tumors from 6 of 10 patients treated with the chemotherapeutic drug temozolomide (TMZ) followed an alternative evolutionary path to high-grade glioma. At recurrence, these tumors were hypermutated and harbored driver mutations in the RB (retinoblastoma) and Akt-mTOR (mammalian target of rapamycin) pathways that bore the signature of TMZ-induced mutagenesis.
Publication
Journal: Science
January/9/1995
Abstract
A Candida albicans gene (CPH1) was cloned that encodes a protein homologous to Saccharomyces cerevisiae Ste12p, a transcription factor that is the target of the pheromone response mitogen-activated protein kinase cascade. CPH1 complements both the mating defect of ste12 haploids and the filamentous growth defect of ste12/ste12 diploids. Candida albicans strains without a functional CPH1 gene (cph1/cph1) show suppressed hyphal formation on solid medium. However, cph1/cph1 strains can still form hyphae in liquid culture and in response to serum. Thus, filamentous growth may be activated in C. albicans by the same signaling kinase cascade that activates Ste12p in S. cerevisiae; however, alternative pathways may exist in C. albicans.
Publication
Journal: Journal of Virology
April/9/2008
Abstract
Accurate identification of the transmitted virus and sequences evolving from it could be instrumental in elucidating the transmission of human immunodeficiency virus type 1 (HIV-1) and in developing vaccines, drugs, or microbicides to prevent infection. Here we describe an experimental approach to analyze HIV-1 env genes as intact genetic units amplified from plasma virion RNA by single-genome amplification (SGA), followed by direct sequencing of uncloned DNA amplicons. We show that this strategy precludes in vitro artifacts caused by Taq-induced nucleotide substitutions and template switching, provides an accurate representation of the env quasispecies in vivo, and has an overall error rate (including nucleotide misincorporation, insertion, and deletion) of less than 8 x 10(-5). Applying this method to the analysis of virus in plasma from 12 Zambian subjects from whom samples were obtained within 3 months of seroconversion, we show that transmitted or early founder viruses can be identified and that molecular pathways and rates of early env diversification can be defined. Specifically, we show that 8 of the 12 subjects were each infected by a single virus, while 4 others acquired more than one virus; that the rate of virus evolution in one subject during an 80-day period spanning seroconversion was 1.7 x 10(-5) substitutions per site per day; and that evidence of strong immunologic selection can be seen in Env and overlapping Rev sequences based on nonrandom accumulation of nonsynonymous mutations. We also compared the results of the SGA approach with those of more-conventional bulk PCR amplification methods performed on the same patient samples and found that the latter is associated with excessive rates of Taq-induced recombination, nucleotide misincorporation, template resampling, and cloning bias. These findings indicate that HIV-1 env genes, other viral genes, and even full-length viral genomes responsible for productive clinical infection can be identified by SGA analysis of plasma virus sampled at intervals typical in large-scale vaccine trials and that pathways of viral diversification and immune escape can be determined accurately.
Publication
Journal: Gene
January/12/2005
Abstract
The construction of Candida albicans mutants by targeted gene disruption usually depends on the use of nutritional markers for the selection of prototrophic transformants from auxotrophic host strains, but it is becoming increasingly evident that this strategy may cause difficulties in the interpretation of mutant phenotypes. Here, we describe a new method for inactivating both alleles of a target gene in C. albicans wild-type strains to obtain homozygous null mutants. The SAT1 flipping method relies on the use of a cassette that contains a dominant nourseothricin resistance marker (caSAT1) for the selection of integrative transformants and a C. albicans-adapted FLP gene that allows the subsequent excision of the cassette, which is flanked by FLP target sequences, from the genome. Two rounds of integration/excision generate homozygous mutants that differ from the wild-type parent strain only by the absence of the target gene, and reintegration of an intact gene copy for complementation of mutant phenotypes is performed in the same way. Transformants are obtained after only 1 day of growth on a selective medium, and integration into the target locus occurs with high specificity after adding homologous flanking sequences on both sides of the cassette. FLP-mediated excision of the SAT1 flipper cassette is achieved by simply growing the transformants for a few hours in medium without selective pressure, and nourseothricin-sensitive (NouS) derivatives can easily be identified by their slower growth on indicator plates containing a low concentration of nourseothricin. We demonstrate the use of the system by deleting the OPT1 gene, which encodes an oligopeptide transporter, in the C. albicans model strain SC5314. The null mutants became resistant to the toxic peptide KLLEth, and reintroduction of an intact OPT1 copy restored susceptibility. The SAT1 flipping method provides a highly efficient method for gene disruption in C. albicans wild-type strains, which eliminates currently encountered problems in the genetic analysis of this important human fungal pathogen.
Publication
Journal: Journal of Clinical Psychiatry
February/16/2004
Abstract
BACKGROUND
The economic burden of depression was estimated to be 43.7 billion dollars in 1990. A subsequent study reported a cost burden of 52.9 billion dollars using revised prevalence data and a refined workplace cost estimation approach. The objective of the current report is to provide a 10-year update of these estimates using the same methodological framework.
METHODS
Using a human capital approach, we developed prevalence-based estimates of 3 major cost categories: (1) direct costs, (2) mortality costs arising from depression-related suicides, and (3) costs associated with depression in the workplace. Cost-of-illness estimates from 1990 were updated to reflect the experience in 2000 using current epidemiologic data and publicly available population, wage, and cost information.
RESULTS
Whereas the treatment rate of depression increased by over 50%, its economic burden rose by only 7%, going from 77.4 billion dollars in 1990 (inflation-adjusted dollars) to 83.1 billion dollars in 2000. Of the 2000 total, 26.1 billion dollars (31%) were direct medical costs, 5.4 billion dollars (7%) were suicide-related mortality costs, and 51.5 billion dollars (62%) were workplace costs.
CONCLUSIONS
The economic burden of depression remained relatively stable between 1990 and 2000, despite a dramatic increase in the proportion of depression sufferers who received treatment. Future research will incorporate additional costs associated with depression sufferers, including the excess costs of their coexisting psychiatric and medical conditions and attention to the role of painful conditions as a driver of these costs.
Publication
Journal: Nature
July/31/2003
Abstract
In the mammalian retina, besides the conventional rod-cone system, a melanopsin-associated photoreceptive system exists that conveys photic information for accessory visual functions such as pupillary light reflex and circadian photo-entrainment. On ablation of the melanopsin gene, retinal ganglion cells that normally express melanopsin are no longer intrinsically photosensitive. Furthermore, pupil reflex, light-induced phase delays of the circadian clock and period lengthening of the circadian rhythm in constant light are all partially impaired. Here, we investigated whether additional photoreceptive systems participate in these responses. Using mice lacking rods and cones, we measured the action spectrum for phase-shifting the circadian rhythm of locomotor behaviour. This spectrum matches that for the pupillary light reflex in mice of the same genotype, and that for the intrinsic photosensitivity of the melanopsin-expressing retinal ganglion cells. We have also generated mice lacking melanopsin coupled with disabled rod and cone phototransduction mechanisms. These animals have an intact retina but fail to show any significant pupil reflex, to entrain to light/dark cycles, and to show any masking response to light. Thus, the rod-cone and melanopsin systems together seem to provide all of the photic input for these accessory visual functions.
Publication
Journal: Journal of Cerebral Blood Flow and Metabolism
September/13/1990
Abstract
A graphical method of analysis applicable to ligands that bind reversibly to receptors or enzymes requiring the simultaneous measurement of plasma and tissue radioactivities for multiple times after the injection of a radiolabeled tracer is presented. It is shown that there is a time t after which a plot of integral of t0ROI(t')dt'/ROI(t) versus integral of t0Cp(t')dt'/ROI(t) (where ROI and Cp are functions of time describing the variation of tissue radioactivity and plasma radioactivity, respectively) is linear with a slope that corresponds to the steady-state space of the ligand plus the plasma volume,.Vp. For a two-compartment model, the slope is given by lambda + Vp, where lambda is the partition coefficient and the intercept is -1/[kappa 2(1 + Vp/lambda)]. For a three-compartment model, the slope is lambda(1 + Bmax/Kd) + Vp and the intercept is -[1 + Bmax/Kd)/k2 + [koff(1 + Kd/Bmax)]-1) [1 + Vp/lambda(1 + Bmax/Kd)]-1 (where Bmax represents the concentration of ligand binding sites and Kd the equilibrium dissociation constant of the ligand-binding site complex, koff (k4) the ligand-binding site dissociation constant, and k2 is the transfer constant from tissue to plasma). This graphical method provides the ratio Bmax/Kd from the slope for comparison with in vitro measures of the same parameter. It also provides an easy, rapid method for comparison of the reproducibility of repeated measures in a single subject, for longitudinal or drug intervention protocols, or for comparing experimental results between subjects. Although the linearity of this plot holds when ROI/Cp is constant, it can be shown that, for many systems, linearity is effectively reached some time before this. This analysis has been applied to data from [N-methyl-11C]-(-)-cocaine ([11C]cocaine) studies in normal human volunteers and the results are compared to the standard nonlinear least-squares analysis. The calculated value of Bmax/Kd for the high-affinity binding site for cocaine is 0.62 +/- 0.20, in agreement with literature values.
Publication
Journal: Bioinformatics
December/4/2012
Abstract
BACKGROUND
Expression quantitative trait loci (eQTL) analysis links variations in gene expression levels to genotypes. For modern datasets, eQTL analysis is a computationally intensive task as it involves testing for association of billions of transcript-SNP (single-nucleotide polymorphism) pair. The heavy computational burden makes eQTL analysis less popular and sometimes forces analysts to restrict their attention to just a small subset of transcript-SNP pairs. As more transcripts and SNPs get interrogated over a growing number of samples, the demand for faster tools for eQTL analysis grows stronger.
RESULTS
We have developed a new software for computationally efficient eQTL analysis called Matrix eQTL. In tests on large datasets, it was 2-3 orders of magnitude faster than existing popular tools for QTL/eQTL analysis, while finding the same eQTLs. The fast performance is achieved by special preprocessing and expressing the most computationally intensive part of the algorithm in terms of large matrix operations. Matrix eQTL supports additive linear and ANOVA models with covariates, including models with correlated and heteroskedastic errors. The issue of multiple testing is addressed by calculating false discovery rate; this can be done separately for cis- and trans-eQTLs.
Publication
Journal: Cell
February/3/1985
Abstract
Two distinct nonoverlapping enhancer elements can be defined within the polyoma enhancer region. In mouse fibroblasts, element A provides a 3-fold higher enhancement of the alpha 2-collagen promoter than element B. In mouse embryonal carcinoma cells, element B shows the same efficiency as in fibroblasts, whereas that of element A decreases by a factor of 3.5. Moreover, a single point mutation (PyEC F9.1) increases the efficiency of element B in both cell types, making it superior to element A in embryonal carcinoma cells. The core of element A is located within a 35 bp region tandem duplicated in several wild-type strains, mostly homologous to a crucial repeated sequence of adenovirus E1a enhancer (Hearing and Shenk, 1983). Element B contains the consensus sequence of Weiher et al. (1982). These two homologies are precisely adjacent to the two DNAase l-hypersensitive sites present in viral chromatin.
Publication
Journal: Neuron
July/16/2007
Abstract
Active adult neurogenesis occurs in discrete brain regions of all mammals and is widely regarded as a neuronal replacement mechanism. Whether adult-born neurons make unique contributions to brain functions is largely unknown. Here we systematically characterized synaptic plasticity of retrovirally labeled adult-born dentate granule cells at different stages during their neuronal maturation. We identified a critical period between 1 and 1.5 months of the cell age when adult-born neurons exhibit enhanced long-term potentiation with increased potentiation amplitude and decreased induction threshold. Furthermore, such enhanced plasticity in adult-born neurons depends on developmentally regulated synaptic expression of NR2B-containing NMDA receptors. Our study demonstrates that adult-born neurons exhibit the same classic critical period plasticity as neurons in the developing nervous system. The transient nature of such enhanced plasticity may provide a fundamental mechanism allowing adult-born neurons within the critical period to serve as major mediators of experience-induced plasticity while maintaining stability of the mature circuitry.
Publication
Journal: Nature Reviews Clinical Oncology
May/18/2011
Abstract
Tumor relapse and metastasis remain major obstacles for improving overall cancer survival, which may be due at least in part to the existence of cancer stem cells (CSCs). CSCs are characterized by tumorigenic properties and the ability to self-renew, form differentiated progeny, and develop resistance to therapy. CSCs use many of the same signaling pathways that are found in normal stem cells, such as Wnt, Notch, and Hedgehog (Hh). The origin of CSCs is not fully understood, but data suggest that they originate from normal stem or progenitor cells, or possibly other cancer cells. Therapeutic targeting of both CSCs and bulk tumor populations may provide a strategy to suppress tumor regrowth. Development of agents that target critical steps in the Wnt, Notch, and Hh pathways will be complicated by signaling cross-talk. The role that embryonic signaling pathways play in the function of CSCs, the development of new anti-CSC therapeutic agents, and the complexity of potential CSC signaling cross-talk are described in this Review.
Publication
Journal: Annual Review of Immunology
August/17/1995
Abstract
In humans and experimental animals the presence of bacterial lipopolysaccharide (endotoxin, LPS) signals the presence of gram-negative bacteria. Recognition of LPS triggers gene induction by myeloid and nonmyeloid lineage cells. These inducible genes encode proteins that include cytokines, adhesive proteins, and enzymes that produce low molecular weight proinflammatory mediators. Together the products of these inducible genes upregulate host defense systems that participate in eliminating the bacterial infection. Unfortunately, these same mediators contribute to a serious human disease known as septic shock. Considerable progress has been made during the past decade in determining the sources, identities, and sequence of release of these mediators. In contrast, until recently, marked gaps in our knowledge existed regarding the identity of the LPS receptor and intracellular signaling pathways responsible for LPS-induced cell activation. The discovery in 1986 of a plasma protein termed LPS binding protein (LBP) led to the discovery of unanticipated mechanisms of LPS-induced cell activation. CD14 was found as a soluble serum protein or as a glycosylphosphatidylinositol (GPI)-anchored protein of myeloid lineage cells; it now occupies a key role in LPS-induced cell activation as we understand it today. Here we discuss how LBP enables LPS binding to CD14 and how complexes of LPS and soluble or GPI-anchored CD14 participate in cell activation. We also review the evidence supporting a model for a functional LPS receptor of myeloid cells, which is multimeric, comprised of GPI-anchored CD14 and a presently unidentified transmembrane protein that together bind LPS and initiate cell activation via kinase cascades.
Publication
Journal: Genes and Development
June/10/1992
Abstract
We demonstrate that four different proteins from calf thymus are able to restore splicing in the same splicing-deficient extract using several different pre-mRNA substrates. These proteins are members of a conserved family of proteins recognized by a monoclonal antibody that binds to active sites of RNA polymerase II transcription. We purified this family of nuclear phosphoproteins to apparent homogeneity by two salt precipitations. The family, called SR proteins for their serine- and arginine-rich carboxy-terminal domains, consists of at least five different proteins with molecular masses of 20, 30, 40, 55, and 75 kD. Microsequencing revealed that they are related but not identical. In four of the family members a repeated protein sequence that encompasses an RNA recognition motif was observed. We discuss the potential role of this highly conserved, functionally related set of proteins in pre-mRNA splicing.
Publication
Journal: Journal of Clinical Investigation
July/11/2011
Abstract
Targeted T cell immunotherapies using engineered T lymphocytes expressing tumor-directed chimeric antigen receptors (CARs) are designed to benefit patients with cancer. Although incorporation of costimulatory endodomains within these CARs increases the proliferation of CAR-redirected T lymphocytes, it has proven difficult to draw definitive conclusions about the specific effects of costimulatory endodomains on the expansion, persistence, and antitumor effectiveness of CAR-redirected T cells in human subjects, owing to the lack of side-by-side comparisons with T cells bearing only a single signaling domain. We therefore designed a study that allowed us to directly measure the consequences of adding a costimulatory endodomain to CAR-redirected T cells. Patients with B cell lymphomas were simultaneously infused with 2 autologous T cell products expressing CARs with the same specificity for the CD19 antigen, present on most B cell malignancies. One CAR encoded both the costimulatory CD28 and the ζ-endodomains, while the other encoded only the ζ-endodomain. CAR+ T cells containing the CD28 endodomain showed strikingly enhanced expansion and persistence compared with CAR+ T cells lacking this endodomain. These results demonstrate the superiority of CARs with dual signal domains and confirm a method of comparing CAR-modified T cells within individual patients, thereby avoiding patient-to-patient variability and accelerating the development of optimal T cell immunotherapies.
Publication
Journal: JAMA - Journal of the American Medical Association
October/23/2011
Abstract
BACKGROUND
Predicting hospital readmission risk is of great interest to identify which patients would benefit most from care transition interventions, as well as to risk-adjust readmission rates for the purposes of hospital comparison.
OBJECTIVE
To summarize validated readmission risk prediction models, describe their performance, and assess suitability for clinical or administrative use.
METHODS
The databases of MEDLINE, CINAHL, and the Cochrane Library were searched from inception through March 2011, the EMBASE database was searched through August 2011, and hand searches were performed of the retrieved reference lists. Dual review was conducted to identify studies published in the English language of prediction models tested with medical patients in both derivation and validation cohorts.
METHODS
Data were extracted on the population, setting, sample size, follow-up interval, readmission rate, model discrimination and calibration, type of data used, and timing of data collection.
RESULTS
Of 7843 citations reviewed, 30 studies of 26 unique models met the inclusion criteria. The most common outcome used was 30-day readmission; only 1 model specifically addressed preventable readmissions. Fourteen models that relied on retrospective administrative data could be potentially used to risk-adjust readmission rates for hospital comparison; of these, 9 were tested in large US populations and had poor discriminative ability (c statistic range: 0.55-0.65). Seven models could potentially be used to identify high-risk patients for intervention early during a hospitalization (c statistic range: 0.56-0.72), and 5 could be used at hospital discharge (c statistic range: 0.68-0.83). Six studies compared different models in the same population and 2 of these found that functional and social variables improved model discrimination. Although most models incorporated variables for medical comorbidity and use of prior medical services, few examined variables associated with overall health and function, illness severity, or social determinants of health.
CONCLUSIONS
Most current readmission risk prediction models that were designed for either comparative or clinical purposes perform poorly. Although in certain settings such models may prove useful, efforts to improve their performance are needed as use becomes more widespread.
Publication
Journal: Brain
September/3/2002
Abstract
Ten able adults with autism or Asperger syndrome and 10 normal volunteers were PET scanned while watching animated sequences. The animations depicted two triangles moving about on a screen in three different conditions: moving randomly, moving in a goal-directed fashion (chasing, fighting), and moving interactively with implied intentions (coaxing, tricking). The last condition frequently elicited descriptions in terms of mental states that viewers attributed to the triangles (mentalizing). The autism group gave fewer and less accurate descriptions of these latter animations, but equally accurate descriptions of the other animations compared with controls. While viewing animations that elicited mentalizing, in contrast to randomly moving shapes, the normal group showed increased activation in a previously identified mentalizing network (medial prefrontal cortex, superior temporal sulcus at the temporo-parietal junction and temporal poles). The autism group showed less activation than the normal group in all these regions. However, one additional region, extrastriate cortex, which was highly active when watching animations that elicited mentalizing, showed the same amount of increased activation in both groups. In the autism group this extrastriate region showed reduced functional connectivity with the superior temporal sulcus at the temporo-parietal junction, an area associated with the processing of biological motion as well as with mentalizing. This finding suggests a physiological cause for the mentalizing dysfunction in autism: a bottleneck in the interaction between higher order and lower order perceptual processes.
Publication
Journal: Cancer Cell
November/14/2005
Abstract
Many tumors display a high rate of glucose utilization, as evidenced by 18-F-2-deoxyglucose PET imaging. One potential advantage of catabolizing glucose through glycolysis at a rate that exceeds bioenergetic need is that the growing cell can redirect the excess glycolytic end product pyruvate toward lipid synthesis. Such de novo lipid synthesis is necessary for membrane production and lipid-based posttranslational modification of proteins. A key enzyme linking glucose metabolism to lipid synthesis is ATP citrate lyase (ACL), which catalyzes the conversion of citrate to cytosolic acetyl-CoA. ACL inhibition by RNAi or the chemical inhibitor SB-204990 limits in vitro proliferation and survival of tumor cells displaying aerobic glycolysis. The same treatments also reduce in vivo tumor growth and induce differentiation.
Publication
Journal: Journal of Neuroscience
December/12/1996
Abstract
Prefrontal (PF) cells were studied in monkeys performing a delayed matching to sample task, which requires working memory. The stimuli were complex visual patterns and to solve the task, the monkeys had to discriminate among the stimuli, maintain a memory of the sample stimulus during the delay periods, and evaluate whether a test stimulus matched the sample presented earlier in the trial. PF cells have properties consistent with a role in all three of these operations. Approximately 25% of the cells responded selectively to different visual stimuli. Half of the cells showed heightened activity during the delay after the sample and, for many of these cells, the magnitude of delay activity was selective for different samples. Finally, more than half of the cells responded differently to the test stimuli depending on whether they matched the sample. Because inferior temporal (IT) cortex also is important for working memory, we compared PF cells with IT cells studied in the same task. Compared with IT cortex, PF responses were less often stimulus-selective but conveyed more information about whether a given test stimulus was a match to the sample. Furthermore, sample-selective delay activity in PF cortex was maintained throughout the trial even when other test stimuli intervened during the delay, whereas delay activity in IT cortex was disrupted by intervening stimuli. The results suggest that PF cortex plays a primary role in working memory tasks and may be a source of feedback inputs to IT cortex, biasing activity in favor of behaviorally relevant stimuli.
Publication
Journal: Computer applications in the biosciences : CABIOS
August/12/1997
Abstract
BACKGROUND
Seq-Gen is a program that will simulate the evolution of nucleotide sequences along a phylogeny, using common models of the substitution process. A range of models of molecular evolution are implemented, including the general reversible model. Nucleotide frequencies and other parameters of the model may be given and site-specific rate heterogeneity can also be incorporated in a number of ways. Any number of trees may be read in and the program will produce any number of data sets for each tree. Thus, large sets of replicate simulations can be easily created. This can be used to test phylogenetic hypotheses using the parametric bootstrap.
BACKGROUND
Seq-Gen can be obtained by WWW from http:/(/)evolve.zoo.ox.ac.uk/Seq-Gen/seq-gen.html++ + or by FTP from ftp:/(/)evolve.zoo.ox.ac.uk/packages/Seq-Gen/. The package includes the source code, manual and example files. An Apple Macintosh version is available from the same sites.
Publication
Journal: Journal of Diabetes Investigation
May/19/2014
Abstract
UNASSIGNED
Diabetes mellitus is a group of diseases associated with various metabolic disorders, the main feature of which is chronic hyperglycemia due to insufficient insulin action. Its pathogenesis involves both genetic and environmental factors. The long-term persistence of metabolic disorders can cause susceptibility to specific complications and also foster arteriosclerosis. Diabetes mellitus is associated with a broad range of clinical presentations, from being asymptomatic to ketoacidosis or coma, depending on the degree of metabolic disorder. CLASSIFICATION TABLES 1 AND 2 AND FIGURE 1: [Table: see text] [Table: see text] Figure 1 A scheme of the relationship between etiology (mechanism) and patho-physiological stages (states) of diabetes mellitus. Arrows pointing right represent worsening of glucose metabolism disorders (including onset of diabetes mellitus). Among the arrow lines, indicates the condition classified as 'diabetes mellitus'. Arrows pointing left represent improvement in the glucose metabolism disorder. The broken lines indicate events of low frequency. For example, in type 2 diabetes mellitus, infection can lead to ketoacidosis and require temporary insulin treatment for survival. Also, once diabetes mellitus has developed, it is treated as diabetes mellitus regardless of improvement in glucose metabolism, therefore, the arrow lines pointing left are filled in black. In such cases, a broken line is used, because complete normalization of glucose metabolism is rare.imageThe classification of glucose metabolism disorders is principally derived from etiology, and includes staging of pathophysiology based on the degree of deficiency of insulin action. These disorders are classified into four groups: (i) type 1 diabetes mellitus; (ii) type 2 diabetes mellitus; (iii) diabetes mellitus due to other specific mechanisms or diseases; and (iv) gestational diabetes mellitus. Type 1 diabetes is characterized by destruction of pancreatic β-cells. Type 2 diabetes is characterized by combinations of decreased insulin secretion and decreased insulin sensitivity (insulin resistance). Glucose metabolism disorders in category (iii) are divided into two subgroups; subgroup A is diabetes in which a genetic abnormality has been identified, and subgroup B is diabetes associated with other pathologic disorders or clinical conditions. The staging of glucose metabolism includes normal, borderline and diabetic stages depending on the degree of hyperglycemia occurring as a result of the lack of insulin action or clinical condition. The diabetic stage is then subdivided into three substages: non-insulin- requiring, insulin-requiring for glycemic control, and insulin-dependent for survival. The two former conditions are called non-insulin-dependent diabetes and the latter is known as insulin-dependent diabetes. In each individual, these stages may vary according to the deterioration or the improvement of the metabolic state, either spontaneously or by treatment. DIAGNOSIS TABLES 3–7 AND FIGURE 2: [Table: see text] [Table: see text] [Table: see text] [Table: see text] [Table: see text] Figure 2 Flow chart outlining steps in the clinical diagnosis of diabetes mellitus. *The value for HbA1c (%) is indicated with 0.4% added to HbA1c (JDS) (%).imageCategories of the State of Glycemia: Confirmation of chronic hyperglycemia is essential for the diagnosis of diabetes mellitus. When plasma glucose levels are used to determine the categories of glycemia, patients are classified as having a diabetic type if they meet one of the following criteria: (i) fasting plasma glucose level of ≥126 mg/dL (≥7.0 mmol/L); (ii) 2-h value of ≥200 mg/dL (≥11.1 mmol/L) in 75 g oral glucose tolerance test (OGTT); or (iii) casual plasma glucose level of ≥200 mg/dL (≥11.1 mmol/L). Normal type is defined as fasting plasma glucose level of <110 mg/dL (<6.1 mmol/L) and 2-h value of <140 mg/dL (<7.8 mmol/L) in OGTT. Borderline type (neither diabetic nor normal type) is defined as falling between the diabetic and normal values. According to the current revision, in addition to the earlier listed plasma glucose values, hemoglobin A1c (HbA1c) has been given a more prominent position as one of the diagnostic criteria. That is, (iv) HbA1c≥6.5% is now also considered to indicate diabetic type. The value of HbA1c, which is equivalent to the internationally used HbA1c (%) (HbA1c [NGSP]) defined by the NGSP (National Glycohemoglobin Standardization Program), is expressed by adding 0.4% to the HbA1c (JDS) (%) defined by the Japan Diabetes Society (JDS). Subjects with borderline type have a high rate of developing diabetes mellitus, and correspond to the combination of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) noted by the American Diabetes Association (ADA) and WHO. Although borderline cases show few of the specific complications of diabetes mellitus, the risk of arteriosclerosis is higher than those of normal type. When HbA1c is 6.0-6.4%, suspected diabetes mellitus cannot be excluded, and when HbA1c of 5.6-5.9% is included, it forms a group with a high risk for developing diabetes mellitus in the future, even if they do not have it currently. Clinical Diagnosis: 1 If any of the criteria for diabetic type (i) through to (iv) is observed at the initial examination, the patient is judged to be 'diabetic type'. Re-examination is conducted on another day, and if 'diabetic type' is reconfirmed, diabetes mellitus is diagnosed. However, a diagnosis cannot be made only by the re-examination of HbA1c alone. Moreover, if the plasma glucose values (any of criteria [i], [ii], or [iii]) and the HbA1c (criterion [iv]) in the same blood sample both indicate diabetic type, diabetes mellitus is diagnosed based on the initial examination alone. If HbA1c is used, it is essential that the plasma glucose level (criteria [i], [ii] or [iii]) also indicates diabetic type for a diagnosis of diabetes mellitus. When diabetes mellitus is suspected, HbA1c should be measured at the same time as examination for plasma glucose.2 If the plasma glucose level indicates diabetic type (any of [i], [ii], or [iii]) and either of the following conditions exists, diabetes mellitus can be diagnosed immediately at the initial examination.• The presence of typical symptoms of diabetes mellitus (thirst, polydipsia, polyuria, weight loss)• The presence of definite diabetic retinopathy3 If it can be confirmed that the above conditions 1 or 2 existed in the past, diabetes mellitus can be diagnosed or suspected regardless of the current test results.4 If the diagnosis of diabetes cannot be established by these procedures, the patient is followed up and re-examined after an appropriate interval.5 The physician should assess not only the presence or absence of diabetes, but also its etiology and glycemic stage, and the presence and absence of diabetic complications or associated conditions. Epidemiological Study: For the purpose of estimating the frequency of diabetes mellitus, 'diabetes mellitus' can be substituted for the determination of 'diabetic type' from a single examination. In this case, HbA1c≥6.5% alone can be defined as 'diabetes mellitus'. Health Screening: It is important not to misdiagnose diabetes mellitus, and thus clinical information such as family history and obesity should be referred to at the time of screening in addition to an index for plasma glucose level. Gestational Diabetes Mellitus: There are two hyperglycemic disorders in pregnancy: (i) gestational diabetes mellitus (GDM); and (ii) diabetes mellitus. GDM is diagnosed if one or more of the following criteria is met in a 75 g OGTT during pregnancy: 1 Fasting plasma glucose level of ≥92 mg/dL (5.1 mmol/L)2 1-h value of ≥180 mg/dL (10.0 mmol/L)3 2-h value of ≥153 mg/dL (8.5 mmol/L) However, diabetes mellitus that is diagnosed by the clinical diagnosis of diabetes mellitus defined earlier is excluded from GDM. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00074.x, 2010).
Publication
Journal: Nature Neuroscience
January/17/2000
Abstract
We used fluorescent in-situ hybridization and confocal microscopy to monitor the subcellular distribution of the immediate-early gene Arc. Arc RNA appeared in discrete intranuclear foci within minutes of neuronal activation and subsequently disappeared from the nucleus and accumulated in the cytoplasm by 30 minutes. The time course of nuclear versus cytoplasmic Arc RNA accumulation was distinct, and could therefore be used to infer the activity history of individual neurons at two times. Following sequential exposure of rats to two different environments or to the same environment twice, the proportion of CA1 neurons with cytoplasmic, nuclear or overlapping Arc expression profiles matched predictions derived from ensemble neurophysiological recordings of hippocampal neuronal ensembles. Arc gene induction is thus specifically linked to neural encoding processes.
Publication
Journal: Nucleic Acids Research
March/24/2002
Abstract
Heterologous markers are important tools required for the molecular dissection of gene function in many organisms, including Saccharomyces cerevisiae. Moreover, the presence of gene families and isoenzymes often makes it necessary to delete more than one gene. We recently introduced a new and efficient gene disruption cassette for repeated use in budding yeast, which combines the heterologous dominant kan(r) resistance marker with a Cre/loxP-mediated marker removal procedure. Here we describe an additional set of four completely heterologous loxP-flanked marker cassettes carrying the genes URA3 and LEU2 from Kluyveromyces lactis, his5(+) from Schizosaccharomyces pombe and the dominant resistance marker ble(r) from the bacterial transposon Tn5, which confers resistance to the antibiotic phleomycin. All five loxP--marker gene--loxP gene disruption cassettes can be generated using the same pair of oligonucleotides and all can be used for gene disruption with high efficiency. For marker rescue we have created three additional Cre expression vectors carrying HIS3, TRP1 or ble(r) as the yeast selection marker. The set of disruption cassettes and Cre expression plasmids described here represents a significant further development of the marker rescue system, which is ideally suited to functional analysis of the yeast genome.
Publication
Journal: Annals of the New York Academy of Sciences
April/19/2010
Abstract
In this review of 100 fMRI studies of speech comprehension and production, published in 2009, activation is reported for: prelexical speech perception in bilateral superior temporal gyri; meaningful speech in middle and inferior temporal cortex; semantic retrieval in the left angular gyrus and pars orbitalis; and sentence comprehension in bilateral superior temporal sulci. For incomprehensible sentences, activation increases in four inferior frontal regions, posterior planum temporale, and ventral supramarginal gyrus. These effects are associated with the use of prior knowledge of semantic associations, word sequences, and articulation that predict the content of the sentence. Speech production activates the same set of regions as speech comprehension but in addition, activation is reported for: word retrieval in left middle frontal cortex; articulatory planning in the left anterior insula; the initiation and execution of speech in left putamen, pre-SMA, SMA, and motor cortex; and for suppressing unintended responses in the anterior cingulate and bilateral head of caudate nuclei. Anatomical and functional connectivity studies are now required to identify the processing pathways that integrate these areas to support language.
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