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1.
Pestic Biochem Physiol ; 153: 161-170, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30744890

RESUMO

Oryctes rhinoceros Linn. is one of the most serious pests of coconuts and other palms. Following bioassay guided method, a larvicidal compound, 22-hydroxyhopane has been isolated for the first time from methanol extract of leaves of Adiantum latifolium Lam. against the pest (LC50 value 20.81 µg/g). It is a hopanoid triterpene with molecular mass of 442.42 g/mol. The compound exhibited antibacterial activity against symbiotic gut bacteria, caused histolysis of midgut tissues and inhibited secretion of digestive enzymes such as protease, amylase and trehalase resulting in weight loss of larvae. Enzyme immunoassay showed an elevation of 20-hydroxyecdysone level in haemolymph causing disruption of metamorphosis of larvae.


Assuntos
Adiantum , Antibacterianos/toxicidade , Besouros/efeitos dos fármacos , Inseticidas/toxicidade , Larva/efeitos dos fármacos , Triterpenos/toxicidade , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Bacillus cereus/efeitos dos fármacos , Besouros/fisiologia , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/enzimologia , Hemolinfa/efeitos dos fármacos , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/fisiologia , Metamorfose Biológica/efeitos dos fármacos , Folhas de Planta , Stenotrophomonas maltophilia/efeitos dos fármacos , Triterpenos/química , Triterpenos/isolamento & purificação
2.
Colorectal Dis ; 20(11): 981-985, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29752845

RESUMO

AIM: Extralevator abdominoperineal resection (ELAPE) may be complicated by perineal wound healing problems and herniation. We report a consecutive series of 38 such patients with selective use of a fasciocutaneous V-Y buttock advancement flap (BAF). METHOD: Data were collected on a series of patients undergoing ELAPE for rectal malignancy between August 2011 and July 2017. Demographics, management and outcomes were recorded prospectively. Perineal wound problems were considered as 'major' if they required packing; otherwise, they were classed as 'minor'. RESULTS: Thirty-eight patients [eight female and 30 male; median age 63 (range: 35-89) years] underwent ELAPE. Thirty-seven had an adenocarcinoma of the rectum and one had a malignant melanoma. The median tumour height (from the anal verge) was 30 (range: 0-80) mm. Sixteen patients had a BAF. The median length of stay was 10 (range: 6-25) days. Primary perineal healing occurred in 18 (47%) patients. Major wound breakdown occurred in three (10%) patients and minor wound breakdown in 17 (45%). Two of the 16 patients having a BAF had major wound breakdown: one wound took 9 weeks to heal completely and the other took 9 months. Of the 22 patients who did not have a BAF, one had a major wound breakdown which closed by 3 months. There were no perineal fistulae or chronic sinuses. There were two perineal herniae that were successfully repaired by perineal insertion of biological mesh (Permacol™; Covidien, Dublin, Ireland). CONCLUSIONS: Selective use of a BAF for perineal closure can give good results in terms of healing and an acceptably low early perineal herniation rate.


Assuntos
Períneo/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Complicações Pós-Operatórias/cirurgia , Protectomia/efeitos adversos , Retalhos Cirúrgicos , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Protectomia/métodos , Neoplasias Retais/cirurgia , Reto/cirurgia , Resultado do Tratamento , Cicatrização
3.
J Therm Biol ; 74: 149-159, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29801621

RESUMO

Exposure of Culex quinquefasciatus larvae to hypothermia or hyperthermia in relation to ecological temperature has resulted in alteration of enzyme activities related to maintenance of free amino acid pool and protein degradation. Sudden changes in water temperature have led to elevation of protein content particularly in molecular weight between 66 and 97.4 kDa. MALDI TOF analysis revealed the presence of putative uncharacterized protein and Phospholipase A2 activating protein in larvae subjected to 40°C for 1 hour which was not found in control and other temperature treated larvae. These proteins may be playing a role in survival of larvae at higher temperatures. Thermal shock has resulted in channeling of free amino acids for protein synthesis and elevation of amino acid catabolism through increased deamination and altered transamination, which resulted in a sharp decrease in free amino acid pool. Inhibition of Leucine amino peptidase and elevation of Cathepsin D, under the influence of thermal shock may be an adaptive response of larvae to prevent unnecessary degradation of protein and at the same time facilitated rapid internal re-organization which may accelerate pupation. Elevated activity of Phenol oxidase and its co-stimulator Trypsin -like Serine protease, along with increased expression of Phospholipase A2 activating protein is a well co-ordinated defense mechanism leading to increased immune response in stressed state. This study assumes significance because variation in environmental conditions such as global warming and their impact on mosquito physiology can influence efficiency of disease vector.


Assuntos
Adaptação Fisiológica , Aminoácidos/metabolismo , Culex/enzimologia , Larva/enzimologia , Estresse Fisiológico , Temperatura , Animais , Catepsina D/metabolismo , Resposta ao Choque Frio , Glutamato Desidrogenase/metabolismo , Resposta ao Choque Térmico , Proteínas de Insetos , Leucil Aminopeptidase/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Serina Endopeptidases/metabolismo , Transaminases/metabolismo
4.
Anaesthesia ; 71(10): 1191-7, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27530359

RESUMO

In addition to being effective and easy to learn how to use, the ideal laryngoscope should be associated with minimal reduction in skill performance during gaps in practice over time. We compared the time taken to intubate the trachea of a manikin by novice medical students immediately after training, and then after 1 month, with no intervening practice. We designed a two-period, four-group, randomised, cross-over trial to compare the Macintosh, Venner(™) A.P. Advance(™) with difficult airway blade, C-MAC(®) with D-Blade and Airtraq(®) with wireless video-viewer. A bougie was used to aid intubation with the Macintosh and the C-MAC. After training, there was no significant difference in median (IQR [range]) intubation time using the videolaryngoscopes compared with the Macintosh, which took 30 (26.5-35 [12-118])s. One month later, the intubation time was longer using the C-MAC (41 (29.5-52 [20-119])s; p = 0.002) and A.P. Advance (40 (28.5-57.5 [21-107])s; p = 0.0003)m compared with the Macintosh (27 (21-29 [16-90])s); there was no difference using the Airtraq (27 (20.5-32.5 [15-94])s; p = 0.258) compared with the Macintosh. While skill acquisition after a brief period of learning and practice was equal for each laryngoscope, performance levels differed after 1 month without practice. In particular, the consistency of performance using the C-MAC and A.P. Advance was worse compared with the Macintosh and the Airtraq. While the clinical significance of this is doubtful, we believe that reliable and consistent performance at laryngoscopy is desirable; for the devices that we tested, this requires regular practice.


Assuntos
Competência Clínica/estatística & dados numéricos , Laringoscópios , Laringoscopia/instrumentação , Estudantes de Medicina/estatística & dados numéricos , Adulto , Estudos Cross-Over , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Manequins , Fatores de Tempo , Adulto Jovem
5.
Anaesthesia ; 70(4): 452-61, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25476726

RESUMO

Concern that laryngoscopy and intubation might create or exacerbate a spinal cord injury has generated extensive research into cervical spinal movement during laryngoscopy. We performed a randomised trial on six cadavers, using three different laryngoscopes, before and after creating a type-2 odontoid peg fracture. Our primary outcome measure was the change in the space available for the spinal cord at the C1/2 segment measured by cinefluoroscopy. Tracheal intubation was performed using a minimal view of the glottis, a bougie, and manual in-line stabilisation. In a cadaveric model of type-2 odontoid fracture, the space available for the cord was preserved in maximum flexion and extension, and changed little on laryngoscopy and intubation.


Assuntos
Articulação Atlantoaxial/fisiopatologia , Intubação Intratraqueal/instrumentação , Laringoscópios , Movimento/fisiologia , Fraturas da Coluna Vertebral/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Cadáver , Vértebras Cervicais/fisiopatologia , Feminino , Fluoroscopia/métodos , Movimentos da Cabeça/fisiologia , Humanos , Intubação Intratraqueal/métodos , Laringoscopia , Processo Odontoide/diagnóstico por imagem , Processo Odontoide/lesões , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/patologia
6.
J Biosci ; 482023.
Artigo em Inglês | MEDLINE | ID: mdl-36924206

RESUMO

Banana pseudo-stem weevil (BPW) Odoiporus longicollis Olivier is a serious pest of Musa cultivars which completes its lifecycle as an internal parasite in the pseudo-stem of susceptible host plants. The larval stage of BPW is destructive and difficult to control as larvae are endophytic. Plantains (bananas), resistant to infestation by BPW, exhibited antixenosis against the larvae. Experimental maintenance of the larvae for 4 days in the live pseudo-stem of the resistant plantain resulted in the disruption of carbohydrate metabolism and imbalance of protein-free amino acid turnover. The pseudo-stem possesses three larvicides: stigmasterol-3-O-glucoside (SOG), sulfoquinovosyl diacylglycerol (SQDG), and betulinic acid (BA). Larvicides cause significant elevation in hemolymph protein and reduction in total free amino acids. Larvae treated with larvicides showed elevated activities of hexokinase, trehalase, and lactic acid dehydrogenase, which resulted in significant decrease of glucose and trehalose but sharp increase of lactic acid. Also, inhibition in the activity of glycogen phosphorylase caused significant increase of fat body glycogen in affected larvae. At LD20 concentration, toxicities by SOG, SQDG, and BA were similar but antixenosis by the resistant host plant was more severe due to the simultaneous action of three larvicides present in the resistant, live pseudo-stem. Disruption of carbohydrate metabolism and imbalance of protein-amino acid turnover due to toxicity by larvicides resulted in slow death of the larvae. The larval body responded against toxicity through the induction of the amy gene, which resulted in increased synthesis of α-amylase. The protein was sequenced as ID AHN 92452.2 with 496 amino acids, and the gene has 1491 nucleotides. Defense mechanisms by the larvae are not sufficient to resist antixenosis by the host plant. SOG, SQDG, and BA can be used synergistically as a larvicide for the control of BPW.


Assuntos
Musa , Gorgulhos , Animais , alfa-Amilases/metabolismo , Gorgulhos/metabolismo , Larva/metabolismo , Aminoácidos/metabolismo
7.
Res Vet Sci ; 159: 93-100, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37104994

RESUMO

The present study was aimed at studying the effects of RF-EMR in causing teratogenic changes in the embryonic development of organisms using chick embryo as a model. The fertilized eggs of the hen were incubated in a digital humidified incubator and exposed to RF-EMR from 2G and 4G mobile phones by ringing at regular time intervals. The dose of RF-EMR was varied by increasing the call duration and number of calls per day, with the lower dose being a call duration of 50 min/day and the higher dose being 90 min/day. The phone kept had a range of radiofrequency between 900 and 1800 MHz and SAR (Specific Absorption Rate) 1.355 (2G) and 1.12 (4G) watts/ kg respectively. The batch of eggs incubated without any exposure to RF-EMR was taken as control. The hatchability of 2G and 4G experimental groups were respectively, 65% and 75% at lower radiation exposure and 40% and 55% at higher radiation exposure. The teratogenic effects of RF-EMR on the morphology of chick embryos manifested as the cross beak, non-retracted yolk sac, macrocephaly, malformed legs and toes, disability in standing and balancing the body and variations in body weight, body length and beak length. The results indicate that the RF-EMR poses potential threats to the developing stages of organisms.


Assuntos
Galinhas , Teratogênese , Embrião de Galinha , Animais , Feminino , Óvulo , Radiação Eletromagnética , Ondas de Rádio/efeitos adversos , Desenvolvimento Embrionário , Campos Eletromagnéticos
8.
Gerontology ; 57(6): 549-58, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21124009

RESUMO

BACKGROUND: Elder abuse is a pervasive human right and public health issue. OBJECTIVES: We aimed to examine the mortality associated with elder abuse across levels of psychological and social factors. METHODS: The Chicago Health and Aging Project (CHAP) is a prospective population-based cohort study that began in 1993. A subset of these participants enrolled between 1993 and 2005 had elder abuse reported to social services agencies (n = 113). Mortality was ascertained during follow-up and with the National Death Index. Psychosocial factors (depression, social network and social engagement) were assessed during the CHAP interview. Cox proportional hazard models were used to assess the mortality of elder abuse across levels of psychosocial factors using time-varying covariate analyses. RESULTS: The median follow-up time for the cohort (n = 7,841) was 7.6 years (interquartile range 3.8-12.4 years). In multivariate analyses, those with highest (hazard ratio (HR) 2.60, 95% CI 1.58-4.28) and middle levels (HR 2.18, 95% CI 1.19-3.99) of depressive symptoms had an increased mortality risk associated with elder abuse. For social network, those with lowest (HR 2.50, 95% CI 1.62-3.87) and middle levels (HR 2.65, 95% CI 1.52-4.60) of social network had increased mortality risk associated with elder abuse. For social engagement, those with lowest (HR 2.32, 95% CI 1.47-3.68) and middle levels (HR 2.59, 95% CI 1.65-5.45) of social engagement had increased mortality risk associated with elder abuse. Among those with lowest levels of depressive symptoms, highest levels of social network and social engagement, there was no significant effect of reported or confirmed elder abuse on mortality risk. CONCLUSION: Mortality risk associated with elder abuse was most prominent among those with higher levels of depressive symptoms and lower levels of social network and social engagement.


Assuntos
Abuso de Idosos/mortalidade , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Chicago/epidemiologia , Estudos de Coortes , Depressão/epidemiologia , Feminino , Humanos , Masculino , Modelos de Riscos Proporcionais , Estudos Prospectivos , Psicologia , Fatores de Risco , Apoio Social
9.
BJS Open ; 5(2)2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33728468

RESUMO

BACKGROUND: The evidence base underlying clinical practice in children's general surgery is poor and high-quality collaborative clinical research is required to address current treatment uncertainties. The aim of this study was, through a consensus process, to identify research priorities for clinical research in this field amongst surgeons who treat children. METHODS: Questions were invited in a scoping survey amongst general surgeons and specialist paediatric surgeons. These were refined by the study team and subsequently prioritized in a two-stage modified Delphi process. RESULTS: In the scoping survey, a total of 226 questions covering a broad scope of children's elective and emergency general surgery were submitted by 76 different clinicians. These were refined to 71 research questions for prioritization. A total of 168 clinicians took part in stage one of the prioritization process, and 157 in stage two. A 'top 10' list of priority research questions was generated for both elective and emergency general surgery of childhood. These cover a range of conditions and concepts, including inguinal hernia, undescended testis, appendicitis, abdominal trauma and enhanced recovery pathways. CONCLUSION: Through consensus amongst surgeons who treat children, 10 priority research questions for each of the elective and emergency fields have been identified. These should provide a basis for the development of high-quality multicentre research projects to address these questions, and ultimately improve outcomes for children requiring surgical care.


Assuntos
Pesquisa Biomédica/normas , Técnica Delphi , Cirurgia Geral/normas , Prioridades em Saúde , Criança , Consenso , Procedimentos Cirúrgicos Eletivos , Humanos , Cirurgiões , Inquéritos e Questionários , Reino Unido
10.
Science ; 240(4851): 420-6, 1988 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-3358127

RESUMO

Important advances are being made in the development of stereoselective organic reactions. Some of the emerging research directions that hold forth great promise in this area deal with the development of chiral catalysts for these processes. This review attempts to unify one aspect of this field, the development of catalysts and catalyst models for the enantioselective addition of hydride and carbon nucleophiles to carbonyl substrates. Mechanistic constructs for the stereodifferentiating transition states are provided.


Assuntos
Aldeídos , Catálise , Química , Cetonas , Estereoisomerismo , Fenômenos Químicos , Metais , Oxirredução
11.
Science ; 221(4614): 949-51, 1983 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-17748463

RESUMO

Plants were regenerated from cultured leaf explants of an inbred variety of Lycopersicon esculentum. Seeds were collected from the regenerated plants and sown in the greenhouse. The resultant plants were then evaluated in the field. Several monogenic mutations segregated in the progeny of regenerated plants. The recovery of single gene mutations is evidence that plant tissue culture can be mutagenic. Complementation tests revealed that one mutation was located on the long arm of chromosome 10.

12.
Science ; 213(4510): 907-9, 1981 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-17775277

RESUMO

Somatic hybrid plants of Nicotiana nesophila and N. stocktonii with N. tabacum (cultivated tobacco) were produced by protoplast fusion. These combinations cannot be achieved with conventional sexual hybridization, yet are important in that the wild Nicotiana species are resistant to numerous diseases. Hybridity was verified by chromosome number, isoenzyme analysis, morphological characteristics, and genetic behavior. Local lesion-type resistance to tobacco mosaic virus has been observed in leaves of these somatic hybrid plants.

13.
Science ; 288(5467): 841-5, 2000 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-10797002

RESUMO

A uranium-lead zircon age for a volcanic ash interstratified with fossil-bearing, shallow marine siliciclastic rocks in the Zimnie Gory section of the White Sea region indicates that a diverse assemblage of body and trace fossils occurred before 555.3 +/- 0.3 million years ago. This age is a minimum for the oldest well-documented triploblastic bilaterian Kimberella. It also makes co-occurring trace fossils the oldest that are reliably dated. This determination of age implies that there is no simple relation between Ediacaran diversity and the carbon isotopic composition of Neoproterozoic seawater.


Assuntos
Evolução Biológica , Fósseis , Sedimentos Geológicos , Invertebrados , Paleontologia , Animais , Isótopos de Carbono , Isótopos , Chumbo/análise , Federação Russa , Água do Mar , Silicatos , Urânio , Zircônio
14.
Trends Genet ; 5(2): 46-50, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2646795

RESUMO

Somaclonal variation, the recovery of genetic changes in plants regenerated from tissue culture, offers an opportunity to uncover natural variability and to use this variability for the development of new varieties. This review focuses on the unique variation generated by this technique and the current use of somaclonal variation to develop new plant varieties.


Assuntos
Variação Genética , Plantas/genética , Cruzamento , Células Clonais , Previsões
15.
BJA Educ ; 21(9): 329-335, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34447579
16.
Stroke ; 36(5): 954-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15774818

RESUMO

BACKGROUND AND PURPOSE: Studies investigating the relation of the apolipoprotein E (apoE) epsilon4 allele to clinical stroke and to vascular changes on magnetic resonance imaging have been conflicting. Little data are available regarding the relation of apoE epsilon4 to cerebral infarctions documented on postmortem examination. METHODS: We studied the apoE epsilon4 allele in 214 deceased members of the Religious Orders Study, a longitudinal clinical-pathologic study of aging and Alzheimer disease. The apoE genotype was determined using DNA from lymphocytes. Brains were removed a median of 5 hours (interquartile range, 5.5) after death. At postmortem examination, age, location, and size of macroscopic chronic cerebral infarctions were recorded from 1-cm coronal slabs after paraformaldehyde fixation. We also examined 20-microm paraffin-embedded sections of midfrontal and calcarine cortex for amyloid angiopathy on a scale of 1 to 4. RESULTS: Subjects included 96 males and 118 females with a mean age at death of 86 years (SD, 7). Sixty-five subjects (30.4%) had at least 1 apoE epsilon4 allele and 76 (35.5%) exhibited cerebral infarctions. More than 74% of the subjects exhibited amyloid angiopathy with a mean score of 1.4+/-1.2. After controlling for age and sex, apoE epsilon4 increased the odds of cerebral infarction by 2.3-fold (95% CI, 1.2 to 4.2). apoE epsilon4 increased the odds of cortical 3.2-fold (95% CI, 1.3 to 7.7) and subcortical infarctions 2.3-fold (95% CI, 1.2 to 4.5). The effect was unchanged after accounting for amyloid angiopathy. CONCLUSIONS: apoE epsilon4 increases the odds of chronic cerebral infarction detected at autopsy in older persons.


Assuntos
Apolipoproteínas E/genética , Infarto Cerebral/genética , Predisposição Genética para Doença , Idoso , Alelos , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Apolipoproteína E4 , Angiopatia Amiloide Cerebral/genética , Angiopatia Amiloide Cerebral/patologia , Infarto Cerebral/classificação , Infarto Cerebral/patologia , Doença Crônica , Feminino , Humanos , Masculino , Doenças Vasculares/genética
17.
Diabetes ; 30(11): 907-10, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7297779

RESUMO

We have investigated the acetylator dimorphism in 55 type I (insulin-dependent) diabetics. The frequency of the fast phenotype (49%) was higher than in the general Northern European population (37%). Although this difference was not significant (chi squared = 2.64, P = 0.1) the combination of our data with data from two other studies produced a significant positive association between the fast acetylator phenotype and type I diabetes (P = 0.00013, relative risk = 2.0). These findings lend support to the concept that more than one genetic locus may be involved in the susceptibility to type I diabetes. No association was found between acetylator phenotypes and diabetic complications.


Assuntos
Diabetes Mellitus Tipo 1/genética , Angiopatias Diabéticas/genética , Retinopatia Diabética/genética , Humanos , Fenótipo
18.
Genetics ; 150(4): 1477-85, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9832525

RESUMO

The Notch receptor signaling pathway regulates cell differentiation during the development of multicellular organisms. A number of genes are known to be components of the pathway or regulators of the Notch signal. One candidate for a modifier of Notch function is the Drosophila Suppressor of deltex gene [Su(dx)]. We have isolated four new alleles of Su(dx) and mapped the gene between 22B4 and 22C2. Loss-of-function Su(dx) mutations were found to suppress phenotypes resulting from loss-of-function of Notch signaling and to enhance gain-of-function Notch mutations. Hairless, a mutation in a known negative regulator of the Notch pathway, was also enhanced by Su(dx). Phenotypes were identified for Su(dx) in wing vein development, and a role was demonstrated for the gene between 20 and 30 hr after puparium formation. This corresponds to the period when the Notch protein is involved in refining the vein competent territories. Taken together, our data indicate a role for Su(dx) as a negative regulator of Notch function.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster/genética , Genes de Insetos , Genes Supressores/genética , Proteínas de Insetos/genética , Proteínas de Membrana/metabolismo , Alelos , Animais , Mapeamento Cromossômico , Genes Supressores/fisiologia , Proteínas de Insetos/fisiologia , Receptores Notch , Transdução de Sinais , Asas de Animais
19.
Genetics ; 152(2): 567-76, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10353900

RESUMO

During development, the Notch receptor regulates many cell fate decisions by a signaling pathway that has been conserved during evolution. One positive regulator of Notch is Deltex, a cytoplasmic, zinc finger domain protein, which binds to the intracellular domain of Notch. Phenotypes resulting from mutations in deltex resemble loss-of-function Notch phenotypes and are suppressed by the mutation Suppressor of deltex [Su(dx)]. Homozygous Su(dx) mutations result in wing-vein phenotypes and interact genetically with Notch pathway genes. We have previously defined Su(dx) genetically as a negative regulator of Notch signaling. Here we present the molecular identification of the Su(dx) gene product. Su(dx) belongs to a family of E3 ubiquitin ligase proteins containing membrane-targeting C2 domains and WW domains that mediate protein-protein interactions through recognition of proline-rich peptide sequences. We have identified a seven-codon deletion in a Su(dx) mutant allele and we show that expression of Su(dx) cDNA rescues Su(dx) mutant phenotypes. Overexpression of Su(dx) also results in ectopic vein differentiation, wing margin loss, and wing growth phenotypes and enhances the phenotypes of loss-of-function mutations in Notch, evidence that supports the conclusion that Su(dx) has a role in the downregulation of Notch signaling.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster/genética , Genes de Insetos/genética , Ligases/genética , Proteínas de Membrana/fisiologia , Receptores de Superfície Celular/fisiologia , Sequência de Aminoácidos , Animais , Clonagem Molecular , Drosophila melanogaster/química , Drosophila melanogaster/enzimologia , Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento , Genes Supressores/genética , Teste de Complementação Genética , Proteínas de Insetos/genética , Dados de Sequência Molecular , Mutação , Fenótipo , Filogenia , Receptores Notch , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Transfecção , Ubiquitina-Proteína Ligases , Asas de Animais/embriologia , Asas de Animais/crescimento & desenvolvimento , Asas de Animais/metabolismo
20.
Arch Intern Med ; 160(20): 3074-80, 2000 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-11074736

RESUMO

BACKGROUND: Late-life depression affects physical health and impedes recovery from physical disability. But whether milder symptoms that occur frequently in the general population increase the risk of developing a disability or decrease the likelihood of recovery remains unclear. OBJECTIVE: To examine the effect of mild symptoms of depression, assessed by a reduced version (10 items, ranging from 0-10) of the Center for Epidemiological Studies-Depression Scale, on the course of physical disability, assessed by items from the Katz Activities of Daily Living Scale, the Rosow-Breslau Functional Health Scale, and the Nagi Index. METHODS: A population-based longitudinal study was conducted, with 6 follow-up interviews of 3434 community-dwelling persons aged 65 years and older in East Boston, Mass. RESULTS: The likelihood of becoming disabled increased with each additional symptom of depression (for the Katz measure: odds ratio, 1.16 per symptom; 95% confidence interval, 1.13-1.19; for the Rosow-Breslau measure: odds ratio, 1.14; 95% confidence interval, 1.11-1.16; and for the Nagi measure: odds ratio, 1.17; 95% confidence interval, 1.14-1.19). As the number of depressive symptoms increased, the likelihood of recovering from a physical disability decreased (for the Katz measure: odds ratio, 0.96; 95% confidence interval, 0.93-0.99; for the Rosow-Breslau measure: odds ratio, 0.86; 95% confidence interval, 0.84-0.89; and for the Nagi measure: odds ratio, 0.89; 95% confidence interval, 0.87-0.91). This effect was not accounted for by age, sex, level of educational attainment, body mass index, or chronic health conditions. CONCLUSION: Mild depressive symptoms in older persons (those aged > or =65 years) are associated with an increased likelihood of becoming disabled and a decreased chance of recovery, regardless of age, sex, and other factors that contribute to physical disability.


Assuntos
Depressão/epidemiologia , Pessoas com Deficiência/psicologia , Idoso , Idoso de 80 Anos ou mais , Pessoas com Deficiência/reabilitação , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Fatores de Tempo
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