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1.
Psychol Med ; 48(2): 249-260, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28625231

RESUMO

BACKGROUND: Sleep disturbances are prominent correlates of acute mood episodes and inadequate recovery in bipolar disorder (BD), yet the mechanistic relationship between sleep physiology and mood remains poorly understood. Using a series of pre-sleep mood inductions and overnight sleep recording, this study examined the relationship between overnight mood regulation and a marker of sleep intensity (non-rapid eye movement sleep slow wave activity; NREM SWA) during the interepisode phase of BD. METHODS: Adults with interepisode BD type 1 (BD; n = 20) and healthy adult controls (CTL; n = 23) slept in the laboratory for a screening night, a neutral mood induction night (baseline), a happy mood induction night, and a sad mood induction night. NREM SWA (0.75-4.75 Hz) was derived from overnight sleep EEG recordings. Overnight mood regulation was evaluated using an affect grid pleasantness rating post-mood induction (pre-sleep) and the next morning. RESULTS: Overnight mood regulation did not differ between groups following the sad or happy inductions. SWA did not significantly change for either group on the sad induction night compared with baseline. In BD only, SWA on the sad night was related to impaired overnight negative mood regulation. On the happy induction night, SWA increased relative to baseline in both groups, though SWA was not related to overnight mood regulation for either group. CONCLUSIONS: These findings indicate that SWA disruption may play a role in sustaining negative mood state from the previous night in interepisode BD. However, positive mood state could enhance SWA in bipolar patients and healthy adults.


Assuntos
Afeto/fisiologia , Transtorno Bipolar/fisiopatologia , Ondas Encefálicas/fisiologia , Polissonografia/métodos , Fases do Sono/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autocontrole , Adulto Jovem
2.
Clin Oral Investig ; 22(4): 1795-1803, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29151196

RESUMO

OBJECTIVES: The aim of this study is to determine the effects of in vitro and in vivo high-dose radiotherapy on microhardness and associated indentation pattern morphology of enamel. MATERIALS AND METHODS: The inner, middle, and outer microhardness of enamel was evaluated using three experimental groups: control (non-radiated); in vitro irradiated; in vivo irradiated. In vitro specimens were exposed to simulated radiotherapy, and in vivo specimens were extracted teeth from oral cancer patients previously treated with radiotherapy. Indentations were measured via SEM images to calculate microhardness values and to assess the mechanomorphological properties of enamel before and after radiotherapy. RESULTS: Middle and outer regions of enamel demonstrated a significant decrease in microhardness after in vitro and in vivo irradiation compared to the control group (p < 0.05). Two indentation patterns were observed: pattern A-presence of microcracks around indent periphery, which represents local dissipation of deformation energy; pattern B-clean, sharp indents. The percentage of clean microindentation patterns, compared to controls, was significantly higher following in vitro and in vivo irradiation in all enamel regions. The highest percentage of clean microindentations (65%) was observed in the in vivo irradiated group in the inner region of enamel near the dentin-enamel junction. CONCLUSIONS: For the first time, this study shows that in vitro and in vivo irradiation alters enamel microhardness. Likewise, the indentation pattern differences suggest that enamel may become more brittle following in vitro and in vivo irradiation. CLINICAL RELEVANCE: The mechanomorphological property changes of enamel following radiation may be a contributory component of pathologic enamel delamination following oral cancer radiotherapy.


Assuntos
Esmalte Dentário/efeitos da radiação , Neoplasias Bucais/radioterapia , Adolescente , Feminino , Testes de Dureza , Humanos , Masculino , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Adulto Jovem
3.
J Dairy Sci ; 100(4): 3004-3018, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28131587

RESUMO

Glucagon-like peptide 2 (GLP-2) therapy was shown previously to reduce inflammation-related gut damage from coccidiosis in dairy calves, and feeding of artificial sweetener stimulates GLP-2 secretion from intestinal L cells. The purpose of this study was to determine whether GLP-2 treatment or artificial sweetener feeding beginning 1 wk before an experimental inoculation with the coccidian parasite Cryptosporidium parvum can reduce infection-related intestinal damage in Holstein bull calves. Newborn calves were assigned to 1 of 4 treatment groups of 6 calves each, including noninfected control calves injected s.c. every 12 h with control buffer (CON), infected control calves injected s.c. every 12 h with control buffer (INF), infected calves injected s.c. every 12 h with 50 µg/kg of body weight of GLP-2 (GLP2), and infected calves injected s.c. every 12 h with control buffer and supplemented in the diet with Sucram (Pancosma, Geneva, Switzerland) at 400 mg/kg of dry matter of milk replacer (SUC). Treatments were initiated on d 1, and calves in INF, GLP2, and SUC were orally dosed on d 8 with 12,500 C. parvum oocysts. Fecal scores were recorded daily, plasma was collected on d 1, 8, 12, 15, and 18 to evaluate markers of inflammation, and fecal samples were collected on d 1, 8, and every other day thereafter to determine the presence of oocysts. Calves were euthanized on d 18 for collection of intestinal tissues and histological and gene expression analyses. Relative to CON, calves in INF exhibited an increase in diarrhea severity, increased plasma serum amyloid A concentration on d 15 and 18, reduced intestinal villus height, increased villus apoptosis and crypt cell proliferation, and increased intestinal mRNA expression of MARVELD2 and GPX2. However, calves in SUC and GLP2 had reduced diarrhea severity and fecal C. parvum oocyst shedding, reduced plasma serum amyloid A concentration on d 15 and 18, and, depending on the intestinal segment, increased villus height, reduced crypt cell proliferation, and reduced mRNA expression of MARVELD2, GPX2, and other tight junction proteins relative to INF. Lastly, GLP2 and SUC exhibited increased intestinal mass-to-length ratio and decreased length-to-empty body weight ratio relative to INF. Our findings suggest that GLP-2 and Sucram treatments administered before a low-level C. parvum exposure may contribute to fewer effects on intestinal integrity, morphology, and inflammation in response to infection, and shorter, denser intestines.


Assuntos
Cryptosporidium parvum , Peptídeo 2 Semelhante ao Glucagon , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Criptosporidiose , Masculino , Edulcorantes
4.
Neurobiol Learn Mem ; 122: 98-109, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25683202

RESUMO

Incorporation of details from waking life events into Rapid Eye Movement (REM) sleep dreams has been found to be highest on the night after, and then 5-7 nights after events (termed, respectively, the day-residue and dream-lag effects). In experiment 1, 44 participants kept a daily log for 10 days, reporting major daily activities (MDAs), personally significant events (PSEs), and major concerns (MCs). Dream reports were collected from REM and Slow Wave Sleep (SWS) in the laboratory, or from REM sleep at home. The dream-lag effect was found for the incorporation of PSEs into REM dreams collected at home, but not for MDAs or MCs. No dream-lag effect was found for SWS dreams, or for REM dreams collected in the lab after SWS awakenings earlier in the night. In experiment 2, the 44 participants recorded reports of their spontaneously recalled home dreams over the 10 nights following the instrumental awakenings night, which thus acted as a controlled stimulus with two salience levels, high (sleep lab) and low (home awakenings). The dream-lag effect was found for the incorporation into home dreams of references to the experience of being in the sleep laboratory, but only for participants who had reported concerns beforehand about being in the sleep laboratory. The delayed incorporation of events from daily life into dreams has been proposed to reflect REM sleep-dependent memory consolidation. However, an alternative emotion processing or emotional impact of events account, distinct from memory consolidation, is supported by the finding that SWS dreams do not evidence the dream-lag effect.


Assuntos
Sonhos/fisiologia , Consolidação da Memória/fisiologia , Sono REM/fisiologia , Adolescente , Adulto , Encéfalo/fisiologia , Eletroencefalografia , Emoções , Feminino , Humanos , Masculino , Fases do Sono , Fatores de Tempo , Adulto Jovem
5.
J Dairy Sci ; 98(5): 3432-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25726101

RESUMO

Tight junction (TJ) proteins are integral factors involved in gut barrier function, and therapy with glucagon-like peptide-2 (GLP-2) enhances gut integrity. Our aim was to assess effects of GLP-2 treatment on mRNA expression of 8 TJ complex proteins in the intestine of dairy calves not infected or infected with Eimeria bovis at 11±3d of age. Mucosal epithelium from jejunum, ileum, and cecum was collected at slaughter from Holstein bull calves assigned to 4 groups: noninfected, buffer-treated (n=5); noninfected, GLP-2 treated (n=4); E. bovis-infected, buffer-treated (n=5); and E. bovis-infected, GLP-2-treated (n=4). Infected calves were orally dosed with 100,000 to 200,000 sporulated E. bovis oocysts on d 0; GLP-2-treated calves received 50 µg of GLP-2/kg of body weight subcutaneously twice daily for 10d beginning on d 18; and buffer-treated calves received an equal injection volume of 0.01 M Na bicarbonate buffer. All calves were killed on d 28. The mRNA expression of coxsackie and adenovirus receptor (CXADR), claudins 1, 2, and 4 (CLDN1, CLDN2, and CLDN4), F11 receptor (F11R), junction adhesion molecule 2 (JAM2), occludin (OCLN), and tight junction protein ZO-1 (TJP1) was determined by real-time quantitative PCR. In jejunum and ileum, an interaction of E. bovis infection and GLP-2 treatment on gene expression was noted. In jejunum of noninfected calves, GLP-2 increased CXADR, CLDN2, OCLN, and TJP1 mRNA expression but had no effect on mRNA expression in infected calves. Treatment with GLP-2 also increased tight junction protein ZO-1 protein expression in jejunum of noninfected calves as determined by immunohistochemistry. In ileum, E. bovis decreased expression of JAM2, OCLN, and TJP1 in buffer-treated calves, and GLP-2 increased TJP1 expression in infected calves. In cecum, E. bovis infection reduced expression of CXADR, CLDN4, F11R, and OCLN, and GLP-2 therapy increased expression of CLDN4, F11R, OCLN, and TJP1. Results are consistent with studies in nonruminants showing decreased expression of TJ complex proteins in the intestinal tract during pathogen-induced diarrhea and increased TJ protein expression in intestinal tissues in response to GLP-2 treatment. In conclusion, E. bovis reduces gene expression of TJ proteins primarily in cecum of calves 28d postinfection, and GLP-2 increases expression of selected TJ genes in intestinal tissues. Use of GLP-2 to improve gut barrier function in ruminants during pathogen-induced diarrhea warrants additional study.


Assuntos
Coccidiose/tratamento farmacológico , Trato Gastrointestinal/parasitologia , Expressão Gênica , Peptídeo 2 Semelhante ao Glucagon/farmacologia , Proteína da Zônula de Oclusão-1/genética , Animais , Animais Recém-Nascidos , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Claudina-1/genética , Claudina-1/metabolismo , Claudina-2/genética , Claudina-2/metabolismo , Claudina-4/genética , Claudina-4/metabolismo , Coccidiose/veterinária , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/genética , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Eimeria/efeitos dos fármacos , Eimeria/isolamento & purificação , Trato Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Molécula A de Adesão Juncional/genética , Molécula A de Adesão Juncional/metabolismo , Ocludina/genética , Ocludina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo
6.
J Dairy Sci ; 97(7): 4193-207, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24767884

RESUMO

Molecular mechanisms regulating rumen epithelial development remain largely unknown. To identify gene networks and regulatory factors controlling rumen development, Holstein bull calves (n=18) were fed milk replacer only (MRO) until 42 d of age. Three calves each were euthanized at 14 and 42 d of age for tissue collection to represent preweaning, and the remaining calves were provided diets of either milk replacer + orchard grass hay (MH; n=6) to initiate weaning without development of rumen papillae, or milk replacer + calf starter (MG; n=6) to initiate weaning and development of rumen papillae. At 56 and 70 d of age, 3 calves from the MH and MG groups were euthanized for collection of rumen epithelium. Total RNA and protein were extracted for microarray analysis and to validate detected changes in selected protein expression, respectively. As expected, calves fed MRO had no rumen papillae and development of papillae was greater in MG versus MH calves. Differentially expressed genes between the MRO diet at d 42 (preweaning) versus the MG or MH diets at d 56 (during weaning) were identified using permutation analysis of differential expression. Expression of 345 and 519 transcripts was uniquely responsive to MG and MH feeding, respectively. Ingenuity Pathway Analysis (Qiagen, Redwood City, CA) indicated that the top-ranked biological function affected by the MG diet was the cell cycle, and TFGB1, FBOX01, and PPARA were identified as key transcriptional regulators of genes responsive to the MG diet and associated with development of rumen papillae. Increased expressions of TGFB1 mRNA and protein in response to the MG diet were confirmed by subsequent analyses. The top-ranking biological function affected by the MH diet was energy production. Receptors for IGF-1 and insulin, ESRRA, and PPARD were identified by ingenuity pathway analysis as transcriptional regulators of genes responsive to the MH diet. Further analysis of TGFB1 and ESRRA mRNA expression in rumen epithelium obtained from a separate ontogenic study of Holstein calves (n=26) euthanized every 7d from birth to 42 d of age showed increases in transcript expression with advancing age, supporting their roles in mediating rumen epithelial development and function during weaning. Additional evaluation of gene expression in the rumen epithelium of adult cows ruminally infused with butyrate also suggested that observed changes in ESRRA mRNA expression in developing calf rumen may be mediated by increased butyrate concentration. Our results identify TGFB1 and ESRRA as likely transcriptional regulators of rumen epithelial development and energy metabolism, respectively, and provide targets for modulation of rumen development and function in the growing calf.


Assuntos
Bovinos/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Receptores de Estrogênio/genética , Fator de Crescimento Transformador beta1/genética , Desmame , Animais , Bovinos/genética , Bovinos/metabolismo , Epitélio/crescimento & desenvolvimento , Epitélio/metabolismo , Mucosa Gástrica/crescimento & desenvolvimento , Mucosa Gástrica/metabolismo , Redes Reguladoras de Genes , Genoma , Masculino , Receptores de Estrogênio/metabolismo , Rúmen/crescimento & desenvolvimento , Rúmen/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Receptor ERRalfa Relacionado ao Estrogênio
7.
Front Hum Neurosci ; 16: 1066453, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36704097

RESUMO

Insufficient sleep is a major health issue. Inadequate sleep is associated with an array of poor health outcomes, including cardiovascular disease, diabetes, obesity, certain forms of cancer, Alzheimer's disease, depression, anxiety, and suicidality. Given concerns with typical sedative hypnotic drugs for treating sleep difficulties, there is a compelling need for alternative interventions. Here, we report results of a non-invasive electrical brain stimulation approach to optimizing sleep involving transcranial alternating current stimulation (tACS). A total of 25 participants (mean age: 46.3, S.D. ± 12.4, 15 females) were recruited for a null-stimulation controlled (Control condition), within subjects, randomized crossed design, that included two variants of an active condition involving 15 min pre-sleep tACS stimulation. To evaluate the impact on sleep quality, the two active tACS stimulation conditions were designed to modulate sleep-dependent neural activity in the theta/alpha frequency bands, with both stimulation types applied to all subjects in separate sessions. The first tACS condition used a fixed stimulation pattern across all participants, a pattern composed of stimulation at 5 and 10 Hz. The second tACS condition used a personalized stimulation approach with the stimulation frequencies determined by each individual's peak EEG frequencies in the 4-6 Hz and 9-11 Hz bands. Personalized tACS stimulation increased sleep quantity (duration) by 22 min compared to a Control condition (p = 0.04), and 19 min compared to Fixed tACS stimulation (p = 0.03). Fixed stimulation did not significantly increase sleep duration compared to Control (mean: 3 min; p = 0.75). For sleep onset, the Personalized tACS stimulation resulted in reducing the onset by 28% compared to the Fixed tACS stimulation (6 min faster, p = 0.02). For a Poor Sleep sub-group (n = 13) categorized with Clinical Insomnia and a high insomnia severity, Personalized tACS stimulation improved sleep duration by 33 min compared to Fixed stimulation (p = 0.02), and 30 min compared to Control condition (p < 0.1). Together, these results suggest that Personalized stimulation improves sleep quantity and time taken to fall asleep relative to Control and Fixed stimulation providing motivation for larger-scale trials for Personalized tACS as a sleep therapeutic, including for those with insomnia.

8.
Int Endod J ; 44(3): 236-44, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21039628

RESUMO

AIM: To evaluate the sealer/dentine interface associated with an epoxy resin sealer using the combination of Goldner's trichrome stain (GTS) and scanning electron microscopy (SEM) to verify the use of the experimental methodology. METHODOLOGY: Extracted human maxillary incisors (6) were subjected to root canal treatment. Subsequent to pulp removal, canal instrumentation and smear layer removal using EDTA and NaOCl, teeth were randomly and equally assigned to a 'wet' or 'dry' group. The 'dry' group was desiccated (95% ethanol/suction/paper points/air-drying), whilst the 'wet' group was treated with a saline rinse/suction/single paper point. Canals were then filled with an epoxy-based resin sealer and warm vertical gutta-percha compaction. After 7-day storage at 37°C, roots from each group were sectioned into apical, middle and coronal horizontal subsections that were cut and split into paired halves and evaluated with GTS or SEM. With GTS sections, hybrid layer and sealer tubular penetration were measured (n=15 measurements/intracanal location/condition) and evaluated using a two-factor repeated measures analysis of variance. The SEM qualitative analysis of paired sections was included as a complementary confirmation of GTS analyses. RESULTS: In dry and wet groups, there was no conspicuous sealer/dentine interface hybrid layer, irrespective of canal location. However, dry specimens exhibited more uniform sealer distribution with deeper tubular penetration in the coronal and middle third (P<0.05). In contrast, there was decreased sealer distribution and tubule penetration in the apical third, regardless of moisture condition (P<0.05). CONCLUSIONS: The experimental methodology (combination of GTS and SEM) can be used to evaluate the intracanal resin sealer/dentine interface. The pilot data indicated that thorough drying of the root canal system may result in improved epoxy resin sealer distribution and deeper resin sealer tubular penetration, especially in the coronal and middle thirds of root canals.


Assuntos
Adaptação Marginal Dentária , Adesivos Dentinários/química , Dentina/ultraestrutura , Resinas Epóxi/química , Materiais Restauradores do Canal Radicular/química , Análise de Variância , Compostos Azo , Corantes , Colagem Dentária , Infiltração Dentária/diagnóstico , Infiltração Dentária/prevenção & controle , Dentina/efeitos dos fármacos , Adesivos Dentinários/farmacologia , Amarelo de Eosina-(YS) , Resinas Epóxi/farmacologia , Humanos , Incisivo , Maxila , Verde de Metila , Projetos Piloto , Materiais Restauradores do Canal Radicular/farmacologia , Água/química
9.
J Dent Res ; 97(5): 483-491, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29328868

RESUMO

For decades, dental schools in the United States have endured a significant faculty shortage. Studies have determined that the top 2 sources of dental faculty are advanced education programs and private practice. Those who have completed both DDS and PhD training are considered prime candidates for dental faculty positions. However, there is no national database to track those trainees and no evidence to indicate that they entered academia upon graduation. The objective of this study was to assess outcomes of dental school-affiliated oral sciences PhD program enrollment, graduates, and placement between 1994 and 2016. Using the American Dental Association annual survey of advanced dental education programs not accredited by the Commission on Dental Accreditation and data obtained from 22 oral sciences PhD programs, we assessed student demographics, enrollment, graduation, and placement. Based on the data provided by program directors, the average new enrollment was 33, and graduation was 26 per year. A total of 605 graduated; 39 did not complete; and 168 were still in training. Among those 605 graduates, 211 were faculty in U.S. academic institutions, and 77 were faculty in foreign institutions. Given that vacant budgeted full-time faculty positions averaged 257 per year during this period, graduates from those oral sciences PhD programs who entered academia in the United States would have filled 9 (3.6%) vacant faculty positions per year. Therefore, PhD programs have consistently generated only a small pipeline of dental school faculty. Better mentoring to retain talent in academia is necessary. Stronger support and creative funding plans are essential to sustain the PhD program. Furthermore, the oral sciences PhD program database should be established and maintained by dental professional organizations to allow assessments of training models, trends of enrollment, graduation, and placement outcomes.


Assuntos
Educação de Pós-Graduação em Odontologia/estatística & dados numéricos , Humanos , Faculdades de Odontologia/estatística & dados numéricos , Inquéritos e Questionários , Estados Unidos
10.
Braz J Biol ; 76(2): 495-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26983086

RESUMO

Stiretrus decastigmus (Herrich-Schaeffer) (Hemiptera: Pentatomidae) is an important predator of the insect pest Microtheca ochroloma Stal (Coleoptera: Chrysomelidae). The present study investigated the pre-imaginal development of S. decastigmus at different temperatures. The temperatures were: 20, 25, and 30 °C, with a relative humidity of 70 ± 10% and a photofase of 12 h, and the nymphs were fed larvae of M. ochroloma. We evaluated the duration and viability of the egg and nymphal stages, the duration of each instar, and the predation potential. The incubation time decreased with increasing temperature, and the viability was highest at 25 °C. The duration of the nymphal stage was inversely proportional to the temperature, ranging from 18 days at 30 °C to 40.6 days at 20 °C. The highest S. decastigmus predation rates were found at 20 °C (90.4 larvae) and 30 °C (72.5 larvae). S. decastigmus showed the highest viability and lowest consumption of larvae of M. ochroloma at 25 °C.


Assuntos
Besouros/fisiologia , Heterópteros/crescimento & desenvolvimento , Controle Biológico de Vetores/métodos , Comportamento Predatório/fisiologia , Temperatura , Animais , Brasil , Fenômenos Ecológicos e Ambientais , Ecossistema , Larva/crescimento & desenvolvimento , Fatores de Tempo
11.
Neuroscience ; 133(4): 911-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15964485

RESUMO

Growing evidence indicates a role for sleep in off-line memory processing, specifically in post-training consolidation. In humans, sleep has been shown to trigger overnight learning on a motor-sequence memory task, while equivalent waking periods produce no such improvement. But while the behavioral characteristics of sleep-dependent motor learning become increasingly well characterized, the underlying neural basis remains unknown. Here we present functional magnetic resonance imaging data demonstrating a change in the representation of a motor memory after a night of sleep. Subjects trained on a motor-skill memory and 12 hours later, after either sleep or wake, were retested during functional magnetic resonance imaging. Following sleep relative to wake, regions of increased activation were expressed in the right primary motor cortex, medial prefrontal lobe, hippocampus and left cerebellum; changes that can support faster motor output and more precise mapping of key-press movements. In contrast, signal decreases were identified in parietal cortices, the left insular cortex, temporal pole and fronto-polar region, reflecting a reduced need for conscious spatial monitoring and a decreased emotional task burden. This evidence of an overnight, systems-level change in the representation of a motor memory holds important implications for acquiring real-life skills and in clinical rehabilitation following brain trauma, such as stroke.


Assuntos
Encéfalo/fisiologia , Memória/fisiologia , Destreza Motora/fisiologia , Plasticidade Neuronal/fisiologia , Sono/fisiologia , Adulto , Encéfalo/irrigação sanguínea , Mapeamento Encefálico/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Oxigênio/sangue , Vigília/fisiologia
12.
J Anim Sci ; 93(2): 492-501, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26020740

RESUMO

Glucagon-like peptide-2 (GLP-2) is a 33-amino acid peptide derived from proteolytic cleavage of proglucagon by prohormone convertase 1/3 in enteroendocrine L cells. Studies conducted in humans, in rodent models, and in vitro indicate that GLP-2 is secreted in response to the presence of molecules in the intestinal lumen, including fatty acids, carbohydrates, amino acids, and bile acids, which are detected by luminal chemosensors. The physiological actions of GLP-2 are mediated by its G protein-coupled receptor expressed primarily in the intestinal tract on enteric neurons, enteroendocrine cells, and myofibroblasts. The biological activity of GLP-2 is further regulated by dipeptidyl peptidase IV, which rapidly cleaves the N-terminus of GLP-2 that is responsible for GLP-2 receptor activation. Within the gut, GLP-2 increases nutrient absorption, crypt cell proliferation, and mesenteric blood flow and decreases gut permeability and motility, epithelial cell apoptosis, and inflammation. Outside the gut, GLP-2 reduces bone resorption, can suppress appetite, and is cytoprotective in the lung. Thus, GLP-2 has been studied intensively as a therapeutic to improve intestinal function of humans during parenteral nutrition and following small bowel resection and, more recently, as a treatment for osteoporosis and obesity-related disorders and to reduce cellular damage associated with inflammation of the gut and lungs. Recent studies demonstrate that many biological actions and properties of GLP-2 in ruminants are similar to those in nonruminants, including the potential to reduce intestinal nitro-oxidative stress in calves caused by parasitic diseases such as coccidiosis. Because of its beneficial impacts on nutrient absorption, gut healing, and normal gut development, GLP-2 therapy offers significant opportunities to improve calf health and production efficiency. However, GLP-2 therapies require an extended time course to achieve desired physiological responses, as well as daily administration because of the hormone's short half-life. Thus, practical means of administration and alternative strategies to enhance basal GLP-2 secretion (e.g., through specific feed additives), which are more likely to achieve consumer acceptance, are needed. Opportunities to address these challenges are discussed.


Assuntos
Trato Gastrointestinal/metabolismo , Peptídeo 2 Semelhante ao Glucagon/fisiologia , Fisiologia Comparada/métodos , Ruminantes/crescimento & desenvolvimento , Animais , Bovinos , Dipeptidil Peptidase 4/metabolismo , Absorção Gastrointestinal/efeitos dos fármacos , Absorção Gastrointestinal/fisiologia , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/crescimento & desenvolvimento , Peptídeo 2 Semelhante ao Glucagon/metabolismo , Peptídeo 2 Semelhante ao Glucagon/farmacologia , Humanos
13.
Arch Oral Biol ; 60(5): 690-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25766468

RESUMO

OBJECTIVE: To understand radiotherapy-induced dental lesions characterized by enamel loss or delamination near the dentine-enamel junction (DEJ), this study evaluated enamel and dentine nano-mechanical properties and chemical composition before and after simulated oral cancer radiotherapy. DESIGN: Sections from seven non-carious third molars were exposed to 2 Gy fractions, 5 days/week for 7 weeks for a total of 70 Gy. Nanoindentation was used to evaluate Young's modulus, while Raman microspectroscopy was used to measure protein/mineral ratios, carbonate/phosphate ratios, and phosphate peak width. All measures were completed prior to and following radiation at the same four buccal and lingual sites 500 and 30 µm from the DEJ in enamel and dentine (E-500, E-30, D-30 and D-500). RESULTS: The elastic modulus of enamel and dentine was significantly increased (P ≤ 0.05) following radiation. Based on Raman spectroscopic analysis, there was a significant decrease in the protein to mineral ratio (2931/430 cm(-1)) following radiation at all sites tested except at D-500, while the carbonate to phosphate ratio (1070/960 cm(-1)) increased at E-30 and decreased at D-500. Finally, phosphate peak width as measured by FWHM at 960 cm(-1) significantly decreased at both D-30 and D-500 following radiation. CONCLUSIONS: Simulated radiotherapy produced an increase in the stiffness of enamel and dentine near the DEJ. Increased stiffness is speculated to be the result of the radiation-induced decrease in the protein content, with the percent reduction much greater in the enamel sites. Such changes in mechanical properties and chemical composition could potentially contribute to DEJ biomechanical failure leading to enamel delamination that occurs post-radiotherapy. However, other analyses are required for a better understanding of radiotherapy-induced effects on tooth structure to improve preventive and restorative treatments for oral cancer patients.


Assuntos
Esmalte Dentário/química , Esmalte Dentário/efeitos da radiação , Dentina/química , Dentina/efeitos da radiação , Dente Serotino/química , Dente Serotino/efeitos da radiação , Módulo de Elasticidade , Humanos , Neoplasias Bucais/radioterapia , Análise Espectral Raman
14.
Endocrinology ; 135(5): 2022-9, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7525260

RESUMO

Kallikreins are a multigene subfamily of serine proteases that may have a role in processing precursors of polypeptide hormones and growth factors. The epidermal growth factor (EGF) immunoreactivity in mouse milk is derived from the membrane-bound EGF precursor located on the lumenal border of the alveolar cells in the mammary gland. Release of EGF into the milk requires the hydrolysis of the EGF precursor at Arg-X cleavage sites. We report the presence of a candidate EGF precursor-processing enzyme in the lactating mouse mammary gland. Kallikrein transcripts in the mouse lactating mammary gland were detected by primer-directed enzyme amplification of complementary DNA (cDNA). Primers to selected conserved regions of the kallikrein cDNA resulted in an amplified product of the predicted size (573 basepairs). Sequence analysis of the product over three nonconserved regions identified mGK-6 (mouse renal kallikrein) as the primary kallikrein in BALB/c mouse lactating mammary gland. Transcription products for the EGF-binding protein (mGK-9), mGK-1, MGK-3, and mGK-4 were not detected by enzyme amplification with specific primers corresponding to these kallikrein cDNAs. Positive immunohistochemical staining of the apical membrane of mammary alveolar cells was detected with a polyclonal antiserum to mouse kallikrein. Incubation of cell membranes isolated from lactating mammary glands released soluble EGF-immunoreactive material. Aprotinin partially inhibited the release of this material, whereas other protease inhibitors, such as leupeptin, benzamidine, and limabean trypsin inhibitor, had no detectable effect. These results support the hypothesis that the release of EGF-immunoreactive material into the milk is in part dependent upon a kallikrein enzyme (mGK-6) in the BALB/c mouse lactating mammary gland.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Calicreínas/análise , Lactação/fisiologia , Glândulas Mamárias Animais/química , Precursores de Proteínas/metabolismo , Animais , Aprotinina/farmacologia , Sequência de Bases , DNA Complementar/análise , DNA Complementar/genética , Fator de Crescimento Epidérmico/análise , Feminino , Imuno-Histoquímica , Glândulas Mamárias Animais/enzimologia , Glândulas Mamárias Animais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Leite/química , Dados de Sequência Molecular , Precursores de Proteínas/análise , Radioimunoensaio , Transcrição Gênica
15.
Endocrinology ; 120(3): 1190-200, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3492368

RESUMO

Since epidermal growth factor (EGF) has been postulated to play a role in embryonic and fetal growth, a study was undertaken to assess the placental degradation and transfer of maternally administered EGF. Before iodination, mouse EGF was purified to homogeneity by reversed-phase HPLC. Approximately 5 ng [125I]iodo-EGF (approximately 10(6) cpm) were injected iv into day 10, day 13, or day 17 pregnant CD-1 mice; radioactivity in plasma, placentas, and conceptuses was measured up to 2 h after injection. The time course analysis revealed an initial rapid decline in total plasma radioactivity followed by an increase that was maximal by approximately 30 min. Gel filtration (G-15, G-50) chromatography of plasma revealed that by 5 min, radioactivity was associated with free 125I and with material much larger than EGF. No apparent degradation of [125I]iodo-EGF occurred after direct incubation with maternal plasma. Placental radioactivity had an initial phase of decay between 1 and 5 min followed by an increase that became maximal between 30 and 60 min. Extracts of placentas made with 4 M urea in 0.2 M Tris-HCl, pH 8.0, and taken 1-30 min after injection revealed radioactivity coeluting predominantly with [125I]iodo-EGF at 1 min but shifting to mostly free 125I by 30 min. Uptake of radioactivity by conceptuses was not evident until about 15 min, and only free 125I was detected in extracts; the same results were obtained when 5 micrograms unlabeled EGF were injected simultaneously with [125I]iodo-EGF. Incubation of placental mince with [125I]iodo-EGF yielded [125I]MIT as the apparent major radioactive degradation product. Formation of [125I]MIT in vitro was both time- and temperature-dependent. At 37 C, marked formation of [125I]MIT was observed; at 22 C, only a negligible amount was formed after incubation of mince with [125I]iodo-EGF for 60 min. Incubation of [125I]iodo-EGF with kidney mince yielded predominantly free 125I. When tissues were incubated directly with [125I]MIT, kidney tissue deiodinated the [125I]MIT, but placental tissue did not. When [125I]iodo-EGF was incubated for up to 2 h with kidney tissue in the presence of excess MIT (unlabeled), the major degradation product eluted as [125I]MIT, instead of free 125I. These findings suggest that the mouse placenta can readily bind and then degrade [125I]iodo-EGF to constituent amino acids.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Placenta/metabolismo , Animais , Cromatografia Líquida de Alta Pressão/métodos , Fator de Crescimento Epidérmico/isolamento & purificação , Receptores ErbB/metabolismo , Feminino , Radioisótopos do Iodo , Rim/metabolismo , Camundongos , Gravidez
16.
Neurology ; 54(8): 1616-25, 2000 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-10762503

RESUMO

BACKGROUND: Case reports and clinical observations suggest that fluctuating cognition (FC) is common in the major dementias, particularly dementia with Lewy bodies (DLB), where it is one of three core clinical diagnostic features. OBJECTIVES: To examine the frequency, characteristics, and diagnostic utility of FC in dementia using clinical, attentional, and EEG markers. METHOD: - A total of 155 subjects (61 with AD, 37 with DLB, 22 with vascular dementia [VaD], 35 elderly controls) received clinical evaluation for FC using a semiquantified measure applied by experienced clinicians and 90-second cognitive choice reaction time (CRT) and vigilance reaction time (VIGRT) trials. Forty subjects also received an evaluation of mean EEG frequency across 90 seconds. RESULTS: Patients with DLB had a greater prevalence and severity of FC than did patients with AD or VaD rated using clinical, attentional, and EEG measures. The 90-second cognitive and EEG trials demonstrated that FC occurs on a second-to-second basis in patients with DLB. Patients with VaD had a higher prevalence of FC than did those with AD, although the profile of FC was different from that expressed by DLB cases. Optimal cutoff values on the clinical scale achieved good discrimination between the dementia groups (sensitivity 81%, specificity 92%, DLB versus AD; sensitivity 81%, specificity 82%, DLB versus VaD; sensitivity 64%, specificity 77%, VaD versus AD). CONCLUSION: Standardized assessment methods demonstrate that FC is significantly more common and severe in DLB than in other major dementias. The periodicity of FC is different in DLB and VaD cases, with important implications for the underlying causal mechanisms and for differential diagnosis.


Assuntos
Doença de Alzheimer/complicações , Transtornos Cognitivos/diagnóstico , Demência Vascular/complicações , Doença por Corpos de Lewy/complicações , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Atenção/fisiologia , Mapeamento Encefálico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Estudos de Coortes , Demência Vascular/diagnóstico , Diagnóstico Diferencial , Eletroencefalografia , Feminino , Humanos , Doença por Corpos de Lewy/diagnóstico , Masculino , Testes Neuropsicológicos , Curva ROC , Tempo de Reação/fisiologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença
17.
J Clin Pathol ; 32(2): 154-7, 1979 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-438345

RESUMO

A 63-year-old woman presented with Raynaud's phenomenon and extensive cold-induced livedo reticularis. A skin biopsy showed no abnormality of the blood vessels but the blood contained high titres of a very unusual autoantibody against the M blood group, most active at low temperatures. An IgM cryoglobulin was detected, and anti-M activity was found in this fraction. The cells of the patient were grouped as MM. The direct antiglobulin test was positive due to C3 component of complement bound to the red cells. The haematological and biochemical results indicate a mild haemolytic process, which is at present well compensated.


Assuntos
Anemia Hemolítica Autoimune/imunologia , Autoanticorpos/análise , Sistema do Grupo Sanguíneo MNSs , Doença de Raynaud/imunologia , Dermatopatias/imunologia , Anemia Hemolítica Autoimune/complicações , Temperatura Baixa , Crioglobulinas/análise , Feminino , Humanos , Pessoa de Meia-Idade , Doença de Raynaud/complicações , Dermatopatias/etiologia
18.
Neuroreport ; 6(14): 1947-51, 1995 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-8547604

RESUMO

The pineal hormone melatonin regulates daily and seasonal rhythms, at least in part through an action on the mammalian biological clock in the suprachiasmatic nuclei (SCN). Melatonin was tested in vitro (10(-15)-10(-6) M; ZT9.5-10.5) for its effect on the circadian peak in neuronal firing rate in the rat SCN slice. It produced a concentration-related phase advance (maximum advance = 3 +/- 0.3 h at 10(-9) M, n = 3; minimum effective concentration = 10(-13) M; EC50 = 1.2 x 10(-12) M). The melatonin receptor antagonist luzindole (10(-5) M) blocked the phase-advance produced by melatonin (10(-9) M), whilst having no effect on its own. These data show that the effect of melatonin on the SCN clock, measured via the circadian rhythm of neuronal firing rate in the nuclei, is consistent with a concentration-dependent action via a high affinity melatonin receptor.


Assuntos
Ritmo Circadiano/fisiologia , Melatonina/fisiologia , Neurônios/fisiologia , Núcleo Supraquiasmático/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Técnicas In Vitro , Masculino , Melatonina/antagonistas & inibidores , Neurônios/efeitos dos fármacos , Ratos , Núcleo Supraquiasmático/citologia , Núcleo Supraquiasmático/efeitos dos fármacos , Triptaminas/farmacologia
19.
Obstet Gynecol ; 79(5 ( Pt 2)): 815-7, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1565375

RESUMO

A woman presented in the third trimester with a recurrence of coccidioidomycosis. She had been treated 5 years earlier for coccidioidal meningitis. We induced delivery, and both mother and infant had favorable outcomes. We believe that this case represents a reactivation of the previously treated disease.


Assuntos
Coccidioidomicose , Pneumopatias Fúngicas , Complicações na Gravidez , Adulto , Feminino , Humanos , Gravidez , Recidiva
20.
Obstet Gynecol ; 77(5): 668-71, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2014077

RESUMO

The relationships among epidural anesthesia, forceps use, parity, episiotomy, and laceration were studied in 9493 uncomplicated vertex deliveries of spontaneous onset and normal course. The use of epidural anesthesia was not associated with an increased incidence or severity of birth-canal trauma. Episiotomy was associated with a decreased rate of perineal laceration, but an overall increase in the rate of perineal trauma. The trauma that did occur with episiotomies was four times more likely to be major than that when no episiotomy was performed.


Assuntos
Anestesia Epidural/efeitos adversos , Episiotomia/efeitos adversos , Períneo/lesões , Feminino , Humanos , Forceps Obstétrico , Paridade , Gravidez , Estudos Retrospectivos , Ferimentos e Lesões/classificação , Ferimentos e Lesões/etiologia
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