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1.
Plant J ; 100(3): 487-504, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31278825

RESUMO

Nicotinamide adenine dinucleotide (NAD+ ) is an essential coenzyme required for all living organisms. In eukaryotic cells, the final step of NAD+ biosynthesis is exclusively cytosolic. Hence, NAD+ must be imported into organelles to support their metabolic functions. Three NAD+ transporters belonging to the mitochondrial carrier family (MCF) have been biochemically characterized in plants. AtNDT1 (At2g47490), focus of the current study, AtNDT2 (At1g25380), targeted to the inner mitochondrial membrane, and AtPXN (At2g39970), located in the peroxisomal membrane. Although AtNDT1 was presumed to reside in the chloroplast membrane, subcellular localization experiments with green fluorescent protein (GFP) fusions revealed that AtNDT1 locates exclusively in the mitochondrial membrane in stably transformed Arabidopsis plants. To understand the biological function of AtNDT1 in Arabidopsis, three transgenic lines containing an antisense construct of AtNDT1 under the control of the 35S promoter alongside a T-DNA insertional line were evaluated. Plants with reduced AtNDT1 expression displayed lower pollen viability, silique length, and higher rate of seed abortion. Furthermore, these plants also exhibited an increased leaf number and leaf area concomitant with higher photosynthetic rates and higher levels of sucrose and starch. Therefore, lower expression of AtNDT1 was associated with enhanced vegetative growth but severe impairment of the reproductive stage. These results are discussed in the context of the mitochondrial localization of AtNDT1 and its important role in the cellular NAD+ homeostasis for both metabolic and developmental processes in plants.


Assuntos
Antiporters/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , NAD/metabolismo , Antiporters/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Transporte Biológico , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Cloroplastos/metabolismo , Citosol/metabolismo , Proteínas de Fluorescência Verde , Homeostase , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mutagênese Insercional , Proteínas de Transporte de Nucleotídeos , Peroxissomos/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Pólen/genética , Pólen/crescimento & desenvolvimento , Pólen/fisiologia , Amido/metabolismo
2.
J Periodontal Res ; 50(4): 519-24, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25244403

RESUMO

BACKGROUND AND OBJECTIVE: Peri-implantitis has a prevalence of 11-47%, involves destruction of peri-implant bone and may lead to implant loss. A detailed understanding of the pathogenesis of peri-implantitis is lacking. The objective of this study was to develop a murine model of experimental peri-implantitis. MATERIAL AND METHODS: Machined, smooth-surface, screw-shaped titanium implants were placed in the healed alveolar bone of the left maxillary molars of C57BL/6J male mice, 8 wk after tooth extraction. Peri-implantitis was induced by securing silk ligatures around the head of the implant fixtures. Implant survival and peri-implant bone levels were analyzed by micro-computed tomography (micro-CT) scans and histology, 12 wk after ligature placement. RESULTS: Implant survival was 60% (six of 10) for implants with ligatures and 100% (eight of eight) for controls. Micro-CT revealed significantly greater bone loss around the implants that received ligatures and that survived, compared with controls. The radiographic findings were confirmed via histology and toluidine blue staining. CONCLUSION: This study describes a murine model of experimental peri-implantitis around screw-shaped titanium implants placed in the edentulous alveolar bone. This model should be a useful tool to dissect pathogenic mechanisms of peri-implantitis and evaluate potential treatment interventions.


Assuntos
Peri-Implantite/etiologia , Ligas , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/patologia , Animais , Corantes , Ligas Dentárias/química , Implantes Dentários , Planejamento de Prótese Dentária , Modelos Animais de Doenças , Masculino , Maxila/diagnóstico por imagem , Maxila/patologia , Maxila/cirurgia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Peri-Implantite/diagnóstico por imagem , Peri-Implantite/patologia , Análise de Sobrevida , Fatores de Tempo , Titânio/química , Cloreto de Tolônio , Alvéolo Dental/diagnóstico por imagem , Alvéolo Dental/patologia , Alvéolo Dental/cirurgia , Microtomografia por Raio-X/métodos
3.
J Med Entomol ; 48(3): 489-95, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21661306

RESUMO

The sand fly Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae: Phlebotominae) is the main vector of American visceral leishmaniasis. Adult males produce a terpenoid sex pheromone that in some cases also acts as male aggregation pheromone. We have analyzed the correlation between male pheromone production levels and pheromone gland cell morphogenesis after adult emergence from pupae. The abdominal tergites of L. longipalpis males were dissected and fixed in glutaraldehyde for transmission electron microscopy, or the pheromone was extracted in analytical grade hexane. Pheromone chemical analysis was carried out at 3- to 6-h intervals during the first 24 h after emergence and continued daily until the seventh day. All extracts were analyzed by gas chromatography. For the morphological analysis, we used insects collected at 0-6, 9-12, 12-14, and 96 h after emergence. Ultrastructural data from 0- to 6-h-old adult males revealed smaller pheromone gland cells with small microvilli at the end apparatus. Lipid droplets and peroxisomes were absent or very rare, but a large number of mitochondria could be seen. Lipid droplets started to appear in the gland cells cytoplasm approximately 9 h after adult emergence, and their number and size increased with age, together with the presence of several peroxisomes, suggesting a role for these organelles in pheromone biosynthesis. At 12-15 h after emergence, the lipid droplets were mainly distributed near the microvilli but were smaller than those in mature older males (4 d old). Pheromone biosynthesis started around 12 h after emergence and increased continuously during the first 3 d, stabilizing thereafter, coinciding with the period when males are more able to attract females.


Assuntos
Psychodidae/crescimento & desenvolvimento , Psychodidae/ultraestrutura , Atrativos Sexuais/biossíntese , Animais , Brasil , Glândulas Exócrinas/crescimento & desenvolvimento , Glândulas Exócrinas/metabolismo , Glândulas Exócrinas/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão , Morfogênese , Atrativos Sexuais/análise , Terpenos/análise
4.
J Exp Bot ; 61(14): 3839-45, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20624762

RESUMO

The NSP-interacting kinase, NIK, belongs to the five leucine-rich repeats-containing receptor-like serine/threonine kinase subfamily that includes members involved in plant development and defence. NIK was first identified by its capacity to interact with the geminivirus nuclear shuttle protein (NSP) and has been strongly associated with plant defence against geminivirus. Recent studies corroborate its function in transducing a defence signal against virus infection and describe components of the NIK-mediated antiviral signalling pathway. This mini-review describes the role of NIK as a transducer of a novel layer of plant innate defence, presents new data on NIK function, and discusses its possible involvement in plant development.


Assuntos
Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Sequência de Aminoácidos , Arabidopsis/metabolismo , Arabidopsis/virologia , Núcleo Celular/metabolismo , Geminiviridae/metabolismo , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Proteínas de Plantas/química , Plantas/enzimologia , Plantas/virologia , Proteínas Serina-Treonina Quinases/química , Transdução de Sinais
5.
Transl Anim Sci ; 4(1): 84-94, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32704969

RESUMO

In Exp. 1, Brachiaria ruziziensis (11.1 % CP) was inoculated or not with two sources of monensin, resulting in three treatments: 1) no monensin inoculation (CONT), 2) 20 mg of monensin sodium-A/kg of DM (Elanco Animal Health; MON-A), and 3) 20 mg of monensin sodium-B/kg of DM (Shandong Qilu King-Phar Pharmaceutical Co. Ltd.; MON-B). Three rumen-fistulated Jersey steers were offered a cool-season forage-based diet and were used as the rumen inoculum donors. Volatile fatty acids concentrations were evaluated at 0, 6, 12, 24, 30, and 48 h after treatment inoculation. Overall, acetate and butyrate concentrations were reduced in MON-A vs. CONT (P ≤ 0.02), whereas both monensin products reduced Ac:Pr ratio vs. CONT (P ≤ 0.01); however, MON-A also (P = 0.05) reduced the Ac:Pr ratio vs. MON-B. A treatment × hour interaction was detected for rumen propionate concentration (P = 0.01), primarily because MON-A resulted in greater propionate than CONT and MON-B at 24 and 48 h (P ≤ 0.03), but no differences were observed between CONT vs. MON-B (P ≥ 0.27). In Exp. 2, 240 Nellore bulls (initial BW = 363.2 ± 40.9 kg) were ranked and blocked according to initial BW, and within blocks animals were allotted into pens (n = 10 pens/treatment). Pens were randomly assigned into one of three treatments: 1) corn-based diet with no monensin (CONT), 2) CONT plus 28 mg of MON-A/kg of DM, and 3) CONT plus 28 mg of MON-B/kg of DM. The CONT diet was composed of sugarcane bagasse, ground corn, DDGS, urea, and a mineral-vitamin mix. The experimental period lasted 106 d and was divided into a 21-d adaptation period and an 85-d finishing phase. During the adaptation phase, both monensin sources increased (P ≤ 0.01) BW change, ADG, and F:G, as well as reduced DMI variation (P = 0.02). When the entire experimental period was evaluated, no treatment effects were detected for final BW, DMI, and ADG (P ≥ 0.26). Nonetheless, DMI variation was reduced as monensin was included (P = 0.01) and only MON-A improved the efficiency by reducing F:G vs. CONT (P = 0.05) and biological efficiency vs. MON-B (P = 0.05). Additionally, carcass ADG tended (P = 0.10) to be greater for MON-A vs. MON-B, whereas no other differences in the carcass characteristics were observed (P ≥ 0.53). In summary, the source of monensin inoculated in vitro and offered to Nellore bulls during the feedlot phase significantly affected the energetic efficiency and the performance of the animals.

6.
Transplant Proc ; 50(5): 1220-1226, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29731163

RESUMO

INTRODUCTION: Despite the improved care of potential organ donors with probable brain death (BD) in the intensive care unit (ICU), few epidemiologic and clinical data are available in developing countries. OBJECTIVES: To evaluate ICU patients with suspected BD aiming to identify factors possibly related to success (organ donation) or failure (nondonation). METHODS: Retrospective cohort study, from the patient records of an adult ICU of a Brazilian teaching hospital for 12 months. Data were tabulated, and descriptive statistics and univariate and multivariate analyses were performed. RESULTS: During the study period, 85 patients with acute neurologic diseases and suspected BD were admitted to the ICU and included for analysis. Of these, there were 9 organ donors (7 liver and 9 kidney donors); 77.7% were men, with a mean age of 39.6 years and admission Acute Physiology and Chronic Health Evaluation II of 25.5. Two-thirds of the patients were victims of trauma. The mean time between acute neurologic event and organ withdrawal was 269 hours. The main prognostic factors related to the success of organ donation were the maximum serum lactate and creatinine levels during ICU admission. CONCLUSIONS: The main clinical factors correlated with nonevolution for organ donation among ICU patients with clinical suspicion of BD were related to patient severity and organic dysfunction: serum lactate and creatinine level. Clinical care and monitoring are emphasized to improve the efficiency of the donation process.


Assuntos
Morte Encefálica/sangue , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos , APACHE , Adolescente , Adulto , Idoso , Brasil , Estudos de Coortes , Cuidados Críticos , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adulto Jovem
7.
Gait Posture ; 19(1): 35-49, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14741302

RESUMO

The results of the inverse dynamic procedures used in gait analysis are known to be highly dependent on the quality of the kinematic and dynamic input data and on the biomechanical model anatomical data. In this paper the sensitivities of the system response to imprecision in the input data and biomechanical model were calculated. It was shown that the gait analysis results were very sensitive to the identification of the point of application of the external forces. The quality of the results was less sensitive to errors made during motion reconstruction and to uncertainties in the biomechanical anatomical data. In this study it is also shown that the adopted inverse dynamic analysis method, based on natural coordinates, effectively shielded any error made on a particular kinematic chain from propagation to other branches of the biomechanical model.


Assuntos
Marcha/fisiologia , Modelos Biológicos , Fenômenos Biomecânicos , Humanos
8.
Arq Bras Cardiol ; 67(6): 407-9, 1996 Dec.
Artigo em Português | MEDLINE | ID: mdl-9246830

RESUMO

A 65 year-old white man, with typical angina pectoris, underwent coronary angiography that showed dual left anterior descending artery (LAD), originating from the right coronary artery (RCA), associated with anomalous origin of the left circumflex artery (LCX) also from the RCA. This an extremely rare coronary artery anomaly and, it is the first case reported, so far. This rareness and clinical significance are emphasized.


Assuntos
Angina Pectoris/complicações , Anomalias dos Vasos Coronários/complicações , Idoso , Cateterismo Cardíaco , Angiografia Coronária , Anomalias dos Vasos Coronários/diagnóstico , Humanos , Masculino
9.
PLoS One ; 8(9): e74898, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24058637

RESUMO

BACKGROUND: The male reproductive system of insects can have several tissues responsible for the secretion of seminal fluid proteins (SFPs), such as testes, accessory glands, seminal vesicles, ejaculatory duct and ejaculatory bulb. The SFPs are transferred during mating and can induce several physiological and behavioral changes in females, such as increase in oviposition and decrease in sexual receptivity after copulation. The phlebotomine Lutzomyia longipalpis is the main vector of visceral leishmaniasis. Despite its medical importance, little is known about its reproductive biology. Here we present morphological aspects of the male L. longipalpis reproductive system by light, scanning and transmission electron microscopy, and compare the mating frequency of both virgin and previously mated females. RESULTS: The male L. longipalpis reproductive system is comprised by a pair of oval-shaped testes linked to a seminal vesicle by vasa deferentia. It follows an ejaculatory duct with an ejaculatory pump (a large bulb enveloped by muscles and associated to tracheas). The terminal endings of the vasa deferentia are inserted into the seminal vesicle by invaginations of the seminal vesicle wall, which is composed by a single layer of gland cells, with well-developed endoplasmic reticulum profiles and secretion granules. Our data suggest that the seminal vesicle acts both as a spermatozoa reservoir and as an accessory gland. Mating experiments support this hypothesis, revealing a decrease in mating frequency after copulation that indicates the effect of putative SFPs. CONCLUSION: Ultrastructural features of the L. longipalpis male seminal vesicle indicated its possible role as an accessory gland. Behavioral observations revealed a reduction in mating frequency of copulated females. Together with transcriptome analyses from male sandfly reproductive organs identifying ESTs encoding orthologs of SFPs, these data indicate the presence of putative L. longipalpis SFPs reducing sexual mating frequency of copulated females.


Assuntos
Dípteros , Retículo Endoplasmático , Proteínas de Insetos/biossíntese , Glândulas Seminais , Espermatozoides , Testículo , Animais , Dípteros/metabolismo , Dípteros/ultraestrutura , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Feminino , Masculino , Reprodução/fisiologia , Glândulas Seminais/metabolismo , Glândulas Seminais/ultraestrutura , Espermatozoides/metabolismo , Espermatozoides/ultraestrutura , Testículo/metabolismo , Testículo/ultraestrutura , Transcriptoma/fisiologia
10.
PLoS One ; 7(4): e34495, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22496818

RESUMO

BACKGROUND: It has been suggested that genes involved in the reproductive biology of insect disease vectors are potential targets for future alternative methods of control. Little is known about the molecular biology of reproduction in phlebotomine sand flies and there is no information available concerning genes that are expressed in male reproductive organs of Lutzomyia longipalpis, the main vector of American visceral leishmaniasis and a species complex. METHODS/PRINCIPAL FINDINGS: We generated 2678 high quality ESTs ("Expressed Sequence Tags") of L. longipalpis male reproductive organs that were grouped in 1391 non-redundant sequences (1136 singlets and 255 clusters). BLAST analysis revealed that only 57% of these sequences share similarity with a L. longipalpis female EST database. Although no more than 36% of the non-redundant sequences showed similarity to protein sequences deposited in databases, more than half of them presented the best-match hits with mosquito genes. Gene ontology analysis identified subsets of genes involved in biological processes such as protein biosynthesis and DNA replication, which are probably associated with spermatogenesis. A number of non-redundant sequences were also identified as putative male reproductive gland proteins (mRGPs), also known as male accessory gland protein genes (Acps). CONCLUSIONS: The transcriptome analysis of L. longipalpis male reproductive organs is one step further in the study of the molecular basis of the reproductive biology of this important species complex. It has allowed the identification of genes potentially involved in spermatogenesis as well as putative mRGPs sequences, which have been studied in many insect species because of their effects on female post-mating behavior and physiology and their potential role in sexual selection and speciation. These data open a number of new avenues for further research in the molecular and evolutionary reproductive biology of sand flies.


Assuntos
Proteínas de Insetos/genética , Insetos Vetores/genética , Psychodidae/genética , Testículo/fisiologia , Transcriptoma/genética , Sequência de Aminoácidos , Animais , Biomarcadores/metabolismo , Biologia Computacional , Etiquetas de Sequências Expressas , Feminino , Masculino , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Filogenia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos
14.
Divulg. saúde debate ; (9): 27-32, ago. 1994.
Artigo em Português | LILACS | ID: lil-223129

RESUMO

Aborda as correlaçöes de temas como educaçäo profissional, prática e exercício profissional e vinte elementos teórico-metodológicos para uma relaçäo igualitária solidária e participativa entre os três temas


Assuntos
Mão de Obra em Saúde/organização & administração , Educação em Saúde , Processo Saúde-Doença , Prática Profissional
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