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BACKGROUND: DSM-5 proposes an Attenuated Psychosis Syndrome (APS) for further investigation, based upon the Attenuated Positive Symptom Syndrome (APSS) in the Structured Interview for Psychosis-Risk Syndromes (SIPS). SIPS Unusual Thought Content, Disorganized Communication and Total Disorganization scores predicted progression to psychosis in a 2015 NAPLS-2 Consortium report. We sought to independently replicate this in a large single-site high-risk cohort, and identify baseline demographic and clinical predictors beyond current APS/APSS criteria. METHOD: We prospectively studied 200 participants meeting criteria for both the SIPS APSS and DSM-5 APS. SIPS scores, demographics, family history of psychosis, DSM Axis-I diagnoses, schizotypy, and social and role functioning were assessed at baseline, with follow-up every 3 months for 2 years. RESULTS: The conversion rate was 30% (n = 60), or 37.7% excluding participants who were followed under 2 years. This rate was stable across time. Conversion time averaged 7.97 months for 60% who developed schizophrenia and 15.68 for other psychoses. Mean conversion age was 20.3 for males and 23.5 for females. Attenuated odd ideas and thought disorder appear to be the positive symptoms which best predict psychosis in a logistic regression. Total negative symptom score, Asian/Pacific Islander and Black/African-American race were also predictive. As no Axis-I diagnosis or schizotypy predicted conversion, the APS is supported as a distinct syndrome. In addition, cannabis use disorder did not increase risk of conversion to psychosis. CONCLUSIONS: NAPLS SIPS findings were replicated while controlling for clinical and demographic factors, strongly supporting the validity of the SIPS APSS and DSM-5 APS diagnosis.
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Progressão da Doença , Sintomas Prodrômicos , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Prognóstico , Transtornos Psicóticos/diagnóstico , Risco , Esquizofrenia/diagnóstico , Adulto JovemRESUMO
Introduction: Vertebrate body axis formation initiates during gastrulation and continues within the tail bud at the posterior end of the embryo. Major structures in the trunk are paired somites, which generate the musculoskeletal system, the spinal cord-forming part of the central nervous system, and the notochord, with important patterning functions. The specification of these different cell lineages by key signalling pathways and transcription factors is essential, however, a global map of cell types and expressed genes in the avian trunk is missing. Methods: Here we use high-throughput sequencing approaches to generate a molecular map of the emerging trunk and tailbud in the chick embryo. Results and Discussion: Single cell RNA-sequencing (scRNA-seq) identifies discrete cell lineages including somites, neural tube, neural crest, lateral plate mesoderm, ectoderm, endothelial and blood progenitors. In addition, RNA-seq of sequential tissue sections (RNA-tomography) provides a spatially resolved, genome-wide expression dataset for the avian tailbud and emerging body, comparable to other model systems. Combining the single cell and RNA-tomography datasets, we identify spatially restricted genes, focusing on somites and early myoblasts. Thus, this high-resolution transcriptome map incorporating cell types in the embryonic trunk can expose molecular pathways involved in body axis development.
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Anthropogenic factors have impacted the diversity and evolutionary trajectory of various species. This can be through factors such as pressure on population size or range, habitat fragmentation, or extensive manipulation and translocation. Here we use time-calibrated data to better understand the pattern and processes of evolution in the heavily manipulated European fallow deer (Dama dama). During the Pleistocene, fallow deer had a broad distribution across Europe and were found as far north as Britain during the Eemian interglacial. The last glacial period saw fallow deer retreat to southern refugia and they did not disperse north afterwards. Their recolonisation was mediated by people and, from northern Europe and the British Isles, fallow deer were transported around the world. We use ancient and modern mitochondrial DNA (mtDNA) and mitogenomic data from Eemian Britain to assess the pattern of change in distribution and lineage structure across Europe over time. We find founder effects and mixed lineages in the northern populations, and stability over time for populations in southern Europe. The Eemian sample was most similar to a lineage currently in Italy, suggesting an early establishment of the relevant refuge. We consider the implications for the integration of anthropogenic and natural processes towards a better understanding of the evolution of fallow deer in Europe.
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Cervos , Humanos , Animais , Cervos/genética , Dinâmica Populacional , Europa (Continente) , DNA Mitocondrial/genética , Reino UnidoRESUMO
BACKGROUND: Myelotoxicity during initial cycles of chemotherapy for Hodgkin lymphoma is associated with better outcome, supporting the concept of individualised dosing based on pharmacodynamic end points to optimise results. This study was performed to identify the maximum tolerated dose (MTD) of doxorubicin within cycles 1-3 ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine). Circulating biomarkers of response (nucleosomal DNA, nDNA) and epithelial toxicity (Cytokeratin 18, CK18) were also measured. METHODS: Dose escalation of doxorubicin in cycles 1-3 ABVD supported by pegfilgrastim was performed on a six-patient cohort basis (35, 45 and 55 mg m(-2)) with doxorubicin reduced to 25 mg m(-2) or omitted in cycles 4-6 to maintain cumulative exposure of 103-130% standard ABVD. BVD was given at standard doses throughout. Six additional subjects were recruited at the MTD. RESULTS: Twenty-four subjects were recruited. Dose-limiting toxicities (DLTs) of grade 3 neuropathy, pneumonitis, palmar-plantar erythema and neutropenic infection were observed at 55 mg m(-2), so 45 mg m(-2) was declared the MTD. In patients who subsequently experienced DLT at any time, large increases in CK18 were seen on day 3 of cycle 1 ABVD. CONCLUSION: Escalated ABVD incorporating doxorubicin at 45 mg m(-2) in cycles 1-3 can be delivered safely with pegfilgrastim support. Circulating cell death biomarkers may assist in the development of future individualised dosing strategies.
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Biomarcadores Farmacológicos/análise , Doxorrubicina/administração & dosagem , Doença de Hodgkin/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais/análise , Bleomicina/administração & dosagem , Bleomicina/efeitos adversos , Estudos de Coortes , Dacarbazina/administração & dosagem , Dacarbazina/efeitos adversos , Relação Dose-Resposta a Droga , Doxorrubicina/efeitos adversos , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Resultado do Tratamento , Função Ventricular Esquerda/efeitos dos fármacos , Vimblastina/administração & dosagem , Vimblastina/efeitos adversos , Adulto JovemRESUMO
The giant deer, or 'Irish elk', has featured extensively in debates on adaptation, sexual selection, and extinction. Its huge antlers--the largest of any deer species, living or extinct--formed a focus of much past work. Yet the phylogenetic position of the giant deer has remained an enigma. On the basis of its flattened antlers, the species was previously regarded as closely related to the living fallow deer. Recent morphological studies, however, have challenged that view and placed the giant deer closer to the living red deer or wapiti. Here we present a new phylogenetic analysis encompassing morphological and DNA sequence evidence, and find that both sets of data independently support a sister-group relationship of giant and fallow deer. Our results include the successful extraction and sequencing of DNA from this extinct species, and highlight the value of a joint molecular and morphological approach.
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Cervos/classificação , Cervos/genética , Fósseis , Filogenia , Animais , Chifres de Veado/anatomia & histologia , Teorema de Bayes , Osso e Ossos/anatomia & histologia , DNA Mitocondrial/análise , DNA Mitocondrial/genética , DNA Mitocondrial/isolamento & purificação , Cervos/anatomia & histologia , Laringe/anatomia & histologia , Masculino , Dados de Sequência Molecular , Polimorfismo Genético/genética , Fatores de TempoRESUMO
The extinction of the many well-known large mammals (megafauna) of the Late Pleistocene epoch has usually been attributed to 'overkill' by human hunters, climatic/vegetational changes or to a combination of both. An accurate knowledge of the geography and chronology of these extinctions is crucial for testing these hypotheses. Previous assumptions that the megafauna of northern Eurasia had disappeared by the Pleistocene/Holocene transition were first challenged a decade ago by the discovery that the latest woolly mammoths on Wrangel Island, northeastern Siberia, were contemporaneous with ancient Egyptian civilization. Here we show that another spectacular megafaunal species, the giant deer or 'Irish elk', survived to around 6,900 radiocarbon yr bp (about 7,700 yr ago) in western Siberia-more than three millennia later than its previously accepted terminal date-and therefore, that the reasons for its ultimate demise are to be sought in Holocene not Pleistocene events. Before their extinction, both giant deer and woolly mammoth underwent dramatic shifts in distribution, driven largely by climatic/vegetational changes. Their differing responses reflect major differences in ecology.
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Biodiversidade , Cervos/fisiologia , Fósseis , Mamíferos/fisiologia , Animais , Chifres de Veado/fisiologia , Biomassa , Radioisótopos de Carbono , Clima Frio , Masculino , Dinâmica Populacional , Sibéria , Fatores de TempoRESUMO
The mammoth lineage provides an example of rapid adaptive evolution in response to the changing environments of the Pleistocene. Using well-dated samples from across the mammoth's Eurasian range, we document geographical and chronological variation in adaptive morphology. This work illustrates an incremental (if mosaic) evolutionary sequence but also reveals a complex interplay of local morphological innovation, migration, and extirpation in the origin and evolution of a mammalian species. In particular, northeastern Siberia is identified as an area of successive allopatric innovations that apparently spread to Europe, where they contributed to a complex pattern of stasis, replacement, and transformation.
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Evolução Biológica , Elefantes , Fósseis , África , Animais , Elefantes/anatomia & histologia , Elefantes/fisiologia , Europa (Continente) , Dente Molar/anatomia & histologia , Paleodontologia , SibériaRESUMO
This study explored the potential for ovarian-derived prostaglandins (PGs) to be involved in the regulation of oocyte maturation and ovulation in zebrafish. It was demonstrated that cultured vitellogenic follicles have the capacity to produce prostaglandin E(2) (PGE(2)) and PGF(2alpha) in response to arachidonic acid (AA) in a concentration-dependent manner, and that AA stimulates the in vitro production of 17beta-estradiol (E(2)). The production of AA-stimulated PGF(2alpha) was significantly reduced by treatment with the non-selective cyclooxygenase (COX) inhibitor, indomethacin (INDO). Treatment of full-grown follicles with AA did not induce oocyte maturation as assessed by germinal vesicle breakdown, but INDO significantly decreased the rate of spontaneous maturation. Using Real-Time PCR, it was shown that follicles of different developmental size classes (primary growth and pre-vitellogenic, early-vitellogenic, and mid- to full-grown vitellogenic) express enzymes that release (cytosolic phospholipase A(2) (cPLA(2)); phospholipase Cgamma1) or metabolize (COX-1, COX-2, and prostaglandin synthase-2) AA to PG metabolites. The expression of cPLA(2) was found to be significantly greater in full-grown follicles compared to follicles of the pre- and early-vitellogenic stages. In vivo studies demonstrated that breeding groups of zebrafish exposed to 100 microg/L INDO exhibited reduced spawning rates and clutch sizes compared with control and 1 microg/L INDO exposed fish. In other studies, it was shown that naturally spawning groups of females exhibit increased ovarian levels of PGF(2alpha), E(2), and 17alpha,20beta-dihydroxy-4-pregnen-3-one (a maturation-inducing hormone in zebrafish) near the time of ovulation compared with non-breeding females. Collectively, these experiments indicate that the AA pathway in zebrafish ovaries is involved in the regulation of oocyte maturation and ovulation and a non-selective inhibitor of COX disrupts these processes.
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Oogênese/fisiologia , Ovulação/fisiologia , Prostaglandinas/fisiologia , Peixe-Zebra/fisiologia , Animais , Ácido Araquidônico/farmacologia , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fosfolipases A2 do Grupo IV/genética , Fosfolipases A2 do Grupo IV/metabolismo , Indometacina/farmacologia , Oogênese/genética , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Ovulação/genética , Prostaglandina-Endoperóxido Sintases/genética , Prostaglandina-Endoperóxido Sintases/metabolismo , Prostaglandinas/metabolismo , Prostaglandinas E/metabolismo , Prostaglandinas E/fisiologia , Prostaglandinas F/metabolismo , Prostaglandinas F/fisiologia , Radioimunoensaio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnicas de Cultura de Tecidos , Peixe-Zebra/genéticaRESUMO
Athabasca oil sands mining in northern Alberta produces process-affected waters that are characterized by the presence of naphthenic acids, polycyclic aromatic hydrocarbons, and high salinity. The purpose of this study was to examine the impact of these process-affected waters on reproductive and stress related endpoints in mature goldfish, Carassius auratus. In two separate studies, testosterone and 17beta-estradiol levels in the plasma were significantly reduced in both male and female goldfish caged for 19 days in process-affected waters relative to controls. This effect was most pronounced in goldfish caged at a site containing mature fine tailing and tailings pond water (P5). Ovarian and testicular tissues from fish in the caging studies were incubated in vitro to evaluate potential differences in basal steroid production levels and responsiveness to human chorionic gonadotropin (hCG). Basal levels of testosterone were reduced significantly in males and females from P5 compared with the control pond (P1) demonstrating that the gonads from exposed fish had a diminished steroidogenic capacity. Gonadal tissues of fish from all ponds responded similarly to hCG suggesting that the steroid biosynthetic pathway remained functionally intact. Plasma cortisol levels were significantly higher in male goldfish caged in a pond containing mature fine tailings and capped with uncontaminated water (P3) and in P5 compared with P1. Collectively, these studies suggest that waste products of oil sands mining have the potential to disrupt the normal endocrine functioning in exposed fish through alterations to both reproductive and glucocorticoid hormone biosynthesis. In additional laboratory studies, exposure of goldfish to a naphthenic acid extract for 7 days failed to replicate the effects of processes-affected waters on plasma steroid levels and the causative agent(s) responsible for the effects on steroid biosynthesis remains to be identified.
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Carpa Dourada/sangue , Hormônios Esteroides Gonadais/sangue , Gônadas/efeitos dos fármacos , Hidrocortisona/sangue , Fígado/efeitos dos fármacos , Petróleo/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Feminino , Água Doce/química , Masculino , Estresse Fisiológico/sangueRESUMO
GABA, the major inhibitory neurotransmitter of the vertebrate brain, has been shown to play an important role in vertebrate reproduction by regulating LH release and sexual behavior. We have studied the expression of the GABA-synthesizing enzyme, glutamic acid decarboxylase (GAD), in goldfish throughout the reproductive cycle in May (mature), November (early gonadal recrudescence) and February (late gonadal recrudescence) and in response to implanted sex steroids. Levels of GAD67 and GAD65 mRNA levels in the hypothalamus of both males and females were highest in the early stages of gonadal recrudescence. In the telencephalon, a different seasonal pattern of GAD expression was evident. The telencephalic expression GAD67, GAD65 and a novel isoform, GAD3, were highest in sexually mature fish in May. Five-day intraperitoneal implantation of gonad-intact fish with testosterone (T), estradiol (E2) or progesterone (P4) did not affect GAD expression in November and February. This is in contrast to results in May when sex differences in steroid responsiveness were evident. Progesterone decreased hypothalamic GAD67 and GAD65 in females and was without effect in males. All other treatments did not alter GAD67, GAD65 or GAD3 expression in the hypothalamus. Both T and P4 decreased GAD67 and GAD65 levels in the telencephalon of male goldfish but had no effect in females. Serum sex steroid levels in control and implanted mature males and females in May were similar so it is unlikely that sex differences in the GAD responses were a result of differences in serum sex steroid levels. These contrasting effects of sex steroids on males and females suggest important sex differences in the regulation of the GADs in sexually mature goldfish.
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Encéfalo/metabolismo , Glutamato Descarboxilase , Carpa Dourada/fisiologia , Hormônios Esteroides Gonadais/metabolismo , Isoenzimas , Estações do Ano , Caracteres Sexuais , Animais , Encéfalo/anatomia & histologia , Feminino , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , RNA Mensageiro/metabolismo , Ácido gama-Aminobutírico/metabolismoRESUMO
The molecular events which confer cellular resistance to cytotoxic drugs such as cytosine arabinoside (ara-C) are poorly understood. Nevertheless, in a proportion of patients with acute leukemia, such events will be responsible for the failure of therapy. Mutations which cause ara-C resistance in a chinese hamster ovary (CHO) cell model have been identified as regulatory base substitutions, occurring in specific sites of the gene coding for an enzyme critical in pyrimidine metabolism, CTP synthetase (CTPs). These cells have elevated dCTP pools, a feature common to biochemical studies of other ara-C resistant leukemic cells. A 94% homology exists between the hamster and human ctps genes. In this study, similar mutations were sought in samples taken from 36 patients, with recurrent or resistant acute leukemia. No mutations were identified in the regions indicated by the CHO model using techniques capable of detecting mutations only if present in more than 10% of the cells studied. Thus, mutations in these sites within the human ctps gene do not appear to be a major mechanism of resistance to ara-C in acute leukemia. Further studies should be directed towards developing more sensitive methods of detection, and these then applied both to CTPs and to other enzymes involved in pyrimidine metabolism.
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Carbono-Nitrogênio Ligases , Citarabina/farmacologia , Leucemia/enzimologia , Ligases/genética , Mutação , Doença Aguda , Adulto , Análise Mutacional de DNA , Resistência a Medicamentos , Humanos , Leucemia/genética , Leucemia/patologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/enzimologiaRESUMO
Mammoths provide a detailed example of species origins and dispersal, but understanding has been impeded by taxonomic confusion, especially in North America. The Columbian mammoth Mammuthus columbi was thought to have evolved in North America from a more primitive Eurasian immigrant. The earliest American mammoths (1.5 million years ago), however, resemble the advanced Eurasian M. trogontherii that crossed the Bering land bridge around that time, giving rise directly to M. columbi. Woolly mammoth M. primigenius later evolved in Beringia and spread into Europe and North America, leading to a diversity of morphologies as it encountered endemic M. trogontherii and M. columbi, respectively. In North America, this included intermediates ("M. jeffersonii"), suggesting introgression of M. primigenius with M. columbi. The lineage illustrates the dynamic interplay of local adaptation, dispersal, and gene flow in the evolution of a widely distributed species complex.
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Evolução Biológica , Mamutes/classificação , Adaptação Fisiológica , Migração Animal , Animais , Europa (Continente) , Fósseis , Fluxo Gênico , Mamutes/anatomia & histologia , Mamutes/genética , Dente Molar/anatomia & histologia , América do Norte , Desgaste dos Dentes/patologiaRESUMO
Weight-loss dieting often leads to loss of control, rebound weight gain, and is a risk factor for binge pathology. Based on findings that food restriction (FR) upregulates sucrose-induced trafficking of glutamatergic AMPA receptors to the nucleus accumbens (NAc) postsynaptic density (PSD), this study was an initial test of the hypothesis that episodic "breakthrough" intake of forbidden food during dieting interacts with upregulated mechanisms of synaptic plasticity to increase reward-driven feeding. Ad libitum (AL) fed and FR subjects consumed a limited amount of 10% sucrose, or had access to water, every other day for 10 occasions. Beginning three weeks after return of FR rats to AL feeding, when 24-h chow intake and rate of body weight gain had normalized, subjects with a history of sucrose intake during FR consumed more sucrose during a four week intermittent access protocol than the two AL groups and the group that had access to water during FR. In an experiment that substituted noncontingent administration of d-amphetamine for sucrose, FR subjects displayed an enhanced locomotor response during active FR but a blunted response, relative to AL subjects, during recovery from FR. This result suggests that the enduring increase in sucrose consumption is unlikely to be explained by residual enhancing effects of FR on dopamine signaling. In a biochemical experiment which paralleled the sucrose behavioral experiment, rats with a history of sucrose intake during FR displayed increased abundance of pSer845-GluA1, GluA2, and GluA3 in the NAc PSD relative to rats with a history of FR without sucrose access and rats that had been AL throughout, whether they had a history of episodic sucrose intake or not. A history of FR, with or without a history of sucrose intake, was associated with increased abundance of GluA1. A terminal 15-min bout of sucrose intake produced a further increase in pSer845-GluA1 and GluA2 in subjects with a history of sucrose intake during FR. Generally, neither a history of sucrose intake nor a terminal bout of sucrose intake affected AMPA receptor abundance in the NAc PSD of AL subjects. Together, these results are consistent with the hypothesis, but the functional contribution of increased synaptic incorporation of AMPA receptors remains to be established.
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Comportamento Alimentar/fisiologia , Privação de Alimentos/fisiologia , Núcleo Accumbens/citologia , Densidade Pós-Sináptica/metabolismo , Receptores de AMPA/metabolismo , Sacarose/administração & dosagem , Edulcorantes/administração & dosagem , Anfetamina/farmacologia , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Estimulantes do Sistema Nervoso Central/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Hipercinese/induzido quimicamente , Masculino , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Frações Subcelulares , Fatores de TempoRESUMO
The African and Asian elephants and the mammoth diverged ca. 4-6 million years ago and their phylogenetic relationship has been controversial. Morphological studies have suggested a mammoth Asian elephant relationship, while molecular studies have produced conflicting results. We obtained cytochrome b sequences of up to 545 base pairs from five mammoths, 14 Asian and eight African elephants. A high degree of polymorphism is detected within species. With a dugong sequence used as the outgroup, parsimony and maximum-likelihood analyses support a mammoth African elephant clade. As the dugong is a very distant outgroup, we employ likelihood analysis to root the tree with a molecular clock, and use bootstrap and Bayesian analyses to quantify the relative support for different topologies. The analyses support the mammoth African elephant relationship, although other trees cannot be rejected. Ancestral polymorphisms may have resulted in gene trees differing from the species phylogeny Examination of morphological data, especially from primitive fossil members, indicates that some supposed synapomorphies between the mammoth and Asian elephant are variable, others convergent or autapomorphous. A mammoth African elephant relationship is not excluded. Our results highlight the need, in both morphological and molecular phylogenetics, for multiple markers and close attention to within-taxon variation and outgroup selection.
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Elefantes/genética , Elefantes/fisiologia , Filogenia , Animais , Sequência de Bases , Grupo dos Citocromos b/genética , DNA Mitocondrial/genética , Elefantes/classificação , Dados de Sequência Molecular , Análise de Sequência de DNARESUMO
A flow-injection analysis-capillary electrochromatography interface is used for gradient elution capillary electrochromatography giving purely electroosmotic flow through the analytical column. Solvent gradients were generated with a micro-LC system connected to the interface. Injections were carried out on-line using an inert rotary LC valve controlled by an electric actuator. Gradient shape was measured from acetonitrile (5% acetone)-water (50:50, v/v) to (100:0) in open tubular experiments. When compared to conventional instrumentation, peak tailing and peak width increased slightly using the interface. A test mixture of nine solutes was evaluated in isocratic and gradient elution modes. Using the interface, a gradient of MeCN-water (60:40) to (90:10) provided baseline separation of all nine solutes in under 18 min with good band spacing. Reproducibility of retention times in eight replicate injections was found to be better than 2% R.S.D. for all solutes. This interface also allows use of autoinjectors and dramatically lessens movement of the packed column, improving column lifetime.
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Cromatografia Líquida de Alta Pressão/instrumentação , Eletroforese Capilar/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Eletroforese Capilar/métodos , Análise de Injeção de Fluxo , Reprodutibilidade dos TestesRESUMO
Polyacrylamide gel electrophoresis and subsequent esterase staining provide an alternative to immunological methods for investigating the diet of microarthropods which cannot be observed directly. Attack rates in field populations of Antarctic microarthropods by the predator Gamasellus racovitzai were calculated by proportional and quantitative analyses of electrophoresis results. Results were quantified by transmission densitometry and a digestion curve for ingested prey esterases was defined. An exponential decay model of digestion, incorporating meal size, was used, and a method potentially enabling both the time since feeding and the composite meal size to be estimated for individual predators is described. These methods are applied to samples of predatory mites collected from the Antarctic Peninsula. Although estimated attack rates were low, about 0.1-0.3 prey per predator per day, they may be sufficient to cause severe local reduction in prey density.
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This paper reports the results of endoscopic sphincterotomy for bile duct stones in 50 patients. A design for a spincterotomy handle and a suitable stainless steel diathermy wire are described. Sphincterotomy was achieved in 45 patients (90%) and complete stone clearance in 42 (84%); this usually required two endoscopic examinations. Complications occurred in nine patients. Haemorrhage and pancreatitis were the most serious resulting in one laparotomy (haemorrhage) and one death (pancreatitis). Periampullary diverticula in 11 patients (22%) did not influence the success rate or the frequency of complications. A "pre-cut" in 11 patients (22%) permitted a later successful sphincterotomy in eight. Stone size (up to 3.5 cm) did not appear to influence outcome, but complete stone clearance was only achieved in two out of eight with more than ten bile duct calculi. Symptoms have not recurred up to three years after sphincterotomy. The data indicate that endoscopic sphincterotomy is of major value in high-risk patients with bile duct calculi and is also appropriate for most low-risk patients with retained stones after cholecystectomy.
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Ampola Hepatopancreática/cirurgia , Cálculos Biliares/cirurgia , Adulto , Idoso , Colangiopancreatografia Retrógrada Endoscópica , Eletrocoagulação , Endoscopia , Feminino , Cálculos Biliares/diagnóstico por imagem , Humanos , Masculino , Métodos , Pessoa de Meia-Idade , Complicações Pós-OperatóriasRESUMO
Membrane introduction mass spectrometry has been applied to on-line monitoring of the reaction of monochloramine with hydrogen chloride. The detection limit for monochloramine introduced by a sheet-membrane direct-insertion probe and measured by electron impact ionization and selected ion detection was found to be 0.7 mg/l. Formation of dichloramine, trichloramine and molecular chlorine in response to the addition of hydrogen chloride to the monochloramine solution was measured on-line. The flow-through membrane introduction mass spectrometry method for detection of chloramines and characterization of their chemistry has minimal memory effects, high molecular specificity, high speed of analysis owing to fast response times, and low detection limits.