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1.
J Wound Ostomy Continence Nurs ; 50(6): 475-483, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37966075

RESUMO

PURPOSE: The purpose of this study was to evaluate clinical and economic outcomes during the first year following ostomy formation. DESIGN: Single-center retrospective audit. SUBJECTS AND SETTING: The sample comprised 200 patients who underwent surgery leading to ileostomy or colostomy at a large English National Health Service (NHS) Trust. METHODS: Clinical complications, medicine prescriptions, and interactions with healthcare services were reported over 12 months postsurgery, and interactions with the NHS were matched to the closest NHS unit cost to determine mean patient cost. RESULTS: The most common ostomy-related surgical site complications were high output (35.0%; n = 70), followed by moderate/severe peristomal skin complications (24.5%; n = 49) and bleeding (23.5%; n = 47). Ostomy management-related complications included general difficulties with ostomy management (50.0%; n = 100) and leakage-related mild peristomal skin issues (48.5%; n = 97). Clinical complication rates were highest in the first quarter following ostomy formation, except parastomal hernia, which increased in incidence over time. Ileostomy patients more frequently experienced high output, acute renal failure, and ostomy management-related complications and had increased length of inpatient admission. However, healthcare resource use was high in both groups, with a median of 13 inpatient admission days and 12 outpatient contacts overall within the first year. Mean cost per patient was £20,444.60 (US $26,018.41); 90.5% of these costs were attributed to ostomy-related factors. CONCLUSIONS: Patients are likely to experience at least one clinical complication following intestinal ostomy formation and have multiple interactions with the NHS. While a number of complications are more frequent in patients with ileostomies, both groups experienced considerable costs within the first year following surgery associated with ostomy management and recovery.


Assuntos
Colostomia , Estomia , Humanos , Colostomia/efeitos adversos , Ileostomia/efeitos adversos , Estudos Retrospectivos , Medicina Estatal , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estomia/efeitos adversos , Custos de Cuidados de Saúde
2.
Osteoporos Int ; 33(10): 2205-2216, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35779100

RESUMO

In Japanese patients who experienced an osteoporotic fracture, 10.8% and 18.6% had a subsequent fracture within 1 and 2 years of follow-up, respectively. Although the burden of hip and vertebral fractures has been reported widely, we found that patients with non-hip non-vertebral (NHNV) fractures had a 26% higher risk of subsequent fracture than patients with hip fractures; therefore, NHNV fractures should also be considered an important risk factor for subsequent fracture. INTRODUCTION: To investigate imminent risk and odds of subsequent osteoporotic fractures and associated risk factors in patients who experienced an initial osteoporotic fracture. METHODS: Patients aged ≥ 50 years with ≥ 1 osteoporotic fracture were analyzed from Japan's Medical Data Vision (MDV) database of claims from acute-care hospitals (January 2012-January 2017). Multivariable models were constructed to explore the impact of key comorbidities and medications on the subsequent fracture risk: Cox proportional hazards model for time to subsequent fracture and logistic regression models for odds of subsequent fracture within 1 and 2 years from index fracture. RESULTS: In total, 32,926 patients were eligible with a median follow-up duration of 12.3 months. The percentage of patients experiencing subsequent fractures was 14.1% across the study duration, and 10.8% and 18.6% in patients with 1 and 2 years of follow-up, respectively. In the Cox proportional hazards model, patients with vertebral or NHNV index fractures had a higher subsequent fracture risk than patients with a hip index fracture (adjusted hazard ratio [aHR] 1.11 and 1.26, respectively); subsequent fracture risk was lower in males than females (aHR 0.89). Patients with baseline claims for tranquilizers and glucocorticoids had a higher subsequent fracture risk than those without (aHR 1.14 and 1.08, respectively). Additionally, baseline claims for anti-Parkinson's medications, alcoholism, and stage 4/5 chronic kidney disease were significantly associated with higher odds of subsequent fracture in the logistic regression models. CONCLUSION: Several clinical and demographic factors were associated with a higher risk and odds of subsequent fracture. This may help to identify patients who should be prioritized for osteoporosis treatment.


Assuntos
Fraturas do Quadril , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Feminino , Fraturas do Quadril/complicações , Fraturas do Quadril/etiologia , Humanos , Japão/epidemiologia , Masculino , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Modelos de Riscos Proporcionais , Fatores de Risco , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/etiologia
3.
Cell ; 185(11): 1905-1923.e25, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35523183

RESUMO

Tumor evolution is driven by the progressive acquisition of genetic and epigenetic alterations that enable uncontrolled growth and expansion to neighboring and distal tissues. The study of phylogenetic relationships between cancer cells provides key insights into these processes. Here, we introduced an evolving lineage-tracing system with a single-cell RNA-seq readout into a mouse model of Kras;Trp53(KP)-driven lung adenocarcinoma and tracked tumor evolution from single-transformed cells to metastatic tumors at unprecedented resolution. We found that the loss of the initial, stable alveolar-type2-like state was accompanied by a transient increase in plasticity. This was followed by the adoption of distinct transcriptional programs that enable rapid expansion and, ultimately, clonal sweep of stable subclones capable of metastasizing. Finally, tumors develop through stereotypical evolutionary trajectories, and perturbing additional tumor suppressors accelerates progression by creating novel trajectories. Our study elucidates the hierarchical nature of tumor evolution and, more broadly, enables in-depth studies of tumor progression.


Assuntos
Neoplasias , Animais , Genes ras , Camundongos , Neoplasias/genética , Filogenia , Sequenciamento do Exoma
4.
J Exp Biol ; 225(10)2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35470386

RESUMO

Climate change and increasing air temperature may alter environmental conditions for developing birds, with a range of phenotypic consequences for offspring. The thermal environment during incubation may affect the trade-off between growth and thermoregulation, but the effects of temperature on the ontogeny of endothermy are not fully understood. Therefore, we experimentally tested whether heating the nest cup of Eurasian blue tits (Cyanistes caeruleus) during incubation would influence cold tolerance of the chicks after hatching. Chicks from both heated and control nests showed a decrease in cooling rate with age as they became increasingly endothermic and homeothermic. However, chicks from previously heated nests cooled at a lower rate per unit surface area and from across the whole body. These chicks also had a greater body mass during the first 12 days of life compared with chicks from control nests. Lower cooling rates in heated chicks may reflect greater thermogenic capacity or a reduced surface area to volume ratio owing to a greater body mass. Future projections for climate change predict rising air temperature and increased likelihood of heatwaves, even in temperate regions. Our results indicate that nest microclimate can affect thermoregulation in offspring, and thus may be used to predict some of the future physiological responses of birds to climate change during breeding.


Assuntos
Temperatura Baixa , Aves Canoras , Animais , Regulação da Temperatura Corporal , Galinhas , Temperatura
5.
FASEB J ; 35(5): e21490, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33829547

RESUMO

Endotherms in cold regions improve heat-producing capacity when preparing for winter. We know comparatively little about how this change is fueled by seasonal adaptation in cellular respiration. Thus, we studied the changes of mitochondrial function in red blood cells in sympatric Coal (Periparus ater), Blue (Cyanistes caeruleus), and Great (Parus major) tits between autumn and winter. These species differ more than twofold in body mass and in several aspects of their foraging ecology and social dominance, which could require differential seasonal adaptation of energy expenditure. Coal and Great tits in particular upregulated the mitochondrial respiration rate and mitochondrial volume in winter. This was not directed toward ATP synthesis, instead reflecting increased uncoupling of electron transport from ATP production. Because uncoupling is exothermic, this increased heat-producing capacity at the sub-cellular level in winter. This previously unexplored the route of thermogenesis in birds should be addressed in future work.


Assuntos
Aclimatação , Metabolismo Energético , Eritrócitos/fisiologia , Mitocôndrias/fisiologia , Passeriformes/fisiologia , Estações do Ano , Termogênese , Animais , Citrato (si)-Sintase/metabolismo , Temperatura Alta
7.
J Food Prot ; 78(9): 1745-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26319730

RESUMO

Cattle are an important reservoir for the foodborne pathogens Salmonella and Escherichia coli O157:H7; they frequently harbor these microorganisms in their digestive tracts and shed them in their feces. Thus, there is potential for contamination of cattle hides and, subsequently, carcasses. Interventions aimed at reducing or eliminating pathogen shedding preharvest will also reduce the likelihood of beef product contamination by these pathogens. Therefore, this study used an in vitro model to evaluate Bdellovibrio bacteriovorus, a gram-negative microorganism that preys upon other gram-negative microorganisms, as a preharvest intervention to control Salmonella and E. coli O157:H7. Rumen fluid and feces were inoculated with pansusceptible or antimicrobial-resistant strains of one pathogen. Control samples were treated with HEPES buffer, whereas experimental samples were exposed to HEPES buffer plus B. bacteriovorus. Salmonella and E. coli O157:H7 populations were quantified at 0, 24, 48, and 72 h. The most-probable-number (MPN) technique, followed by streaking onto xylose lysine Tergitol 4 agar, was used to determine Salmonella populations, whereas spread plating onto sorbitol MacConkey agar supplemented with cefixime and tellurite was employed to enumerate E. coli O157:H7. B. bacteriovorus reduced pansusceptible Salmonella in cattle feces by 2.02 Log MPN/g (P = 0.0005) and antimicrobial-resistant Salmonella by 3.79 (P < 0.0001) and 2.24 (P = 0.0013) Log MPN/g after 24 and 48 h, respectively, in comparison to control samples. Significant reductions were not observed for E. coli O157:H7 in rumen or feces. These data suggest that further investigation into B. bacteriovorus efficacy as a preharvest intervention to control Salmonella in cattle is warranted.


Assuntos
Bdellovibrio/isolamento & purificação , Agentes de Controle Biológico , Bovinos/microbiologia , Escherichia coli O157/crescimento & desenvolvimento , Animais , Bdellovibrio/crescimento & desenvolvimento , Escherichia coli O157/isolamento & purificação , Fezes/microbiologia , Rúmen/microbiologia , Salmonella/crescimento & desenvolvimento , Salmonella/isolamento & purificação
8.
Proc Natl Acad Sci U S A ; 110(15): 6187-92, 2013 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-23530224

RESUMO

We previously demonstrated that cardiac myosin can use 2-deoxy-ATP (dATP) as an energy substrate, that it enhances contraction and relaxation with minimal effect on calcium-handling properties in vitro, and that contractile enhancement occurs with only minor elevation of cellular [dATP]. Here, we report the effect of chronically enhanced dATP concentration on cardiac function using a transgenic mouse that overexpresses the enzyme ribonucleotide reductase (TgRR), which catalyzes the rate-limiting step in de novo deoxyribonucleotide biosynthesis. Hearts from TgRR mice had elevated left ventricular systolic function compared with wild-type (WT) mice, both in vivo and in vitro, without signs of hypertrophy or altered diastolic function. Isolated cardiomyocytes from TgRR mice had enhanced contraction and relaxation, with no change in Ca(2+) transients, suggesting targeted improvement of myofilament function. TgRR hearts had normal ATP and only slightly decreased phosphocreatine levels by (31)P NMR spectroscopy, and they maintained rate responsiveness to dobutamine challenge. These data demonstrate long-term (at least 5-mo) elevation of cardiac [dATP] results in sustained elevation of basal left ventricular performance, with maintained ß-adrenergic responsiveness and energetic reserves. Combined with results from previous studies, we conclude that this occurs primarily via enhanced myofilament activation and contraction, with similar or faster ability to relax. The data are sufficiently compelling to consider elevated cardiac [dATP] as a therapeutic option to treat systolic dysfunction.


Assuntos
Regulação da Expressão Gênica , Miocárdio/metabolismo , Ribonucleotídeo Redutases/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Ecocardiografia , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Transgênicos , Miócitos Cardíacos/citologia , Fenótipo , Ribonucleotídeo Redutases/genética , Sarcômeros/metabolismo , Sístole , Transgenes
10.
J Exp Biol ; 214(Pt 9): 1498-512, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21490258

RESUMO

The chemosensory signal structure governing the upstream progress of blue crabs to an odorant source was examined. We used a three-dimensional laser-induced fluorescence system to collect chemical concentration data simultaneously with behavior observations of actively tracking blue crabs (Callinectes sapidus) in a variety of plume types. This allowed us to directly link chemical signal properties at the antennules and legs to subsequent upstream motion while altering the spatial and temporal intermittency characteristics of the sensory field. Our results suggest that odorant stimuli elicit responses in a binary fashion by causing upstream motion, provided the concentration at the antennules exceeds a specific threshold. In particular, we observed a significant association between crab velocity changes and odorant spike encounters defined using a threshold that is scaled to the mean of the instantaneous maximum concentration. Thresholds were different for each crab, indicating a context-sensitive response to signal dynamics. Our data also indicate that high frequency of odorant spike encounters terminate upstream movement. Further, the data provide evidence that the previous state of the crab and prior stimulus history influence the behavioral response (i.e. the response is context dependent). Two examples are: (1) crabs receiving prior odorant spikes attained elevated velocity more quickly in response to subsequent spikes; and (2) prior acceleration or deceleration of the crab influenced the response time period to a particular odorant spike. Finally, information from both leg and antennule chemosensors interact, suggesting parallel processing of odorant spike properties during navigation.


Assuntos
Braquiúros/fisiologia , Locomoção/fisiologia , Odorantes , Rios , Animais , Antenas de Artrópodes/fisiologia , Reologia , Limiar Sensorial/fisiologia , Fatores de Tempo
11.
J Exp Biol ; 214(Pt 9): 1513-22, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21490259

RESUMO

This study examined the role of broadly distributed sensor populations in chemosensory searching, especially cross-stream heading adjustment. We used three-dimensional laser-induced fluorescence to collect chemical concentration data simultaneously with behavior observations of actively tracking blue crabs (Callinectes sapidus). Our analysis indicates that the spatial distribution of the odorant concentration field is necessary and sufficient to mediate correct cross-stream motion, although concentration provides information that supplements that obtained from the spatial distribution. Crab movement is continually adjusted to maintain an upstream heading, with corrections toward the source modulated only in the presence of chemical cues. Crabs detect and respond to shifts in the position of the center-of-mass (COM) of the odorant concentration distribution as small as 5% of the leg span, which corresponds to ∼0.8-0.9 cm. The reaction time after a 5% threshold shift in the position of the COM is in the range of 2-4 s. Data also indicate that these steering responses are dependent on stimulus history or other characteristics of the plume, with crabs taking longer to respond in conditions with large-scale spatial meanders. Although cross-stream motion is determined by chemical signal inputs to receptors on the walking legs, crabs do make rotational movements in response to chemical signals impinging on the antennules. These rotational movements do not affect the direction of travel, but rather, determine the crab's body angle with respect to the flow. Interestingly, these body angles seem to represent a compromise between reducing drag and obtaining better chemical signal information, and this trade-off is resolved differently under different plume conditions.


Assuntos
Braquiúros/fisiologia , Locomoção/fisiologia , Odorantes , Rios , Movimentos da Água , Animais , Fatores de Tempo
12.
Dev Biol ; 348(2): 177-89, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20920498

RESUMO

The male germ cell-specific fatty acid-binding protein 9 (FABP9/PERF15) is the major component of the murine sperm perforatorium and perinuclear theca. Based on its cytoskeletal association and sequence homology to myelin P2 (FABP8), it has been suggested that FABP9 tethers sperm membranes to the underlying cytoskeleton. Furthermore, its upregulation in apoptotic testicular germ cells and its increased phosphorylation status during capacitation suggested multiple important functions for FABP9. Therefore, we investigated specific functions for FABP9 by means of targeted gene disruption in mice. FABP9(-/-) mice were viable and fertile. Phenotypic analysis showed that FABP9(-/-) mice had significant increases in sperm head abnormalities (~8% greater than their WT cohorts); in particular, we observed the reduction or absence of the characteristic structural element known as the "ventral spur" in ~10% of FABP9(-/-) sperm. However, deficiency of FABP9 affected neither membrane tethering to the perinuclear theca nor the fatty acid composition of sperm. Moreover, epididymal sperm numbers were not affected in FABP9(-/-) mice. Therefore, we conclude that FABP9 plays only a minor role in providing the murine sperm head its characteristic shape and is not absolutely required for spermatogenesis or sperm function.


Assuntos
Proteínas de Ligação a Ácido Graxo/genética , Cabeça do Espermatozoide/ultraestrutura , Sequência de Aminoácidos , Animais , Embrião de Mamíferos/metabolismo , Fertilidade/genética , Humanos , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Cabeça do Espermatozoide/fisiologia , Espermatogênese/genética
13.
Nucleic Acids Res ; 38(22): 8208-18, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20724444

RESUMO

Ribonucleotide reductase (RNR) is the rate-limiting enzyme in deoxyribonucleoside triphosphate (dNTP) biosynthesis, with important roles in nuclear genome maintenance. RNR is also essential for maintenance of mitochondrial DNA (mtDNA) in mammals. The mechanisms regulating mtDNA copy number in mammals are only being discovered. In budding yeast, RNR overexpression resulted in increased mtDNA levels, and rescued the disease phenotypes caused by a mutant mtDNA polymerase. This raised the question of whether mtDNA copy number increase by RNR induction could be a strategy for treating diseases with mtDNA mutations. We show here that high-level overexpression of RNR subunits (Rrm1, Rrm2 and p53R2; separately or in different combinations) in mice does not result in mtDNA copy number elevation. Instead, simultaneous expression of two RNR subunits leads to imbalanced dNTP pools and progressive mtDNA depletion in the skeletal muscle, without mtDNA mutagenesis. We also show that endogenous RNR transcripts are downregulated in response to large increases of mtDNA in mice, which is indicative of nuclear-mitochondrial crosstalk with regard to mtDNA copy number. Our results establish that RNR is not limiting for mtDNA copy number in mice, and provide new evidence for the importance of balanced dNTP pools in mtDNA maintenance in postmitotic tissues.


Assuntos
DNA Mitocondrial/metabolismo , Ribonucleotídeo Redutases/metabolismo , Animais , Variações do Número de Cópias de DNA , DNA Mitocondrial/química , Desoxirribonucleotídeos/metabolismo , Camundongos , Camundongos Transgênicos , Músculo Esquelético/metabolismo , Mutagênese , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Ribonucleotídeo Redutases/genética
14.
J Sports Sci Med ; 8(3): 435-42, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-24150008

RESUMO

UNLABELLED: Music and video are utilised by recreational gym users to enhance their exercise experience. Music and video have not been investigated for their combined ergogenic effect during high intensity exercise. To induce fatigue, this study was performed in warm (~26°C), moist conditions (~50%RH). Six, non-acclimated, male participants took part in the study. Each participant completed three 30-minute exercise bouts on a motorised treadmill under three counterbalanced conditions on separate days: control (CON), motivational music plus video intervention (M), non-motivational intervention (NM). They completed a warm-up (5 km·h(-1) [5 minutes], 9km·h(-1) [10 minutes]) followed by a maximal effort run (15 minutes). Participants did not receive any feedback of time elapsed, distance run or speed. MEASURES: Distance covered (metres), heart rate, blood lactate accumulation (B(lac)) and ratings of perceived exertion (RPE). Participants in the M condition ran significantly further than in the NM (M: 3524 [388]metres; NM: 3110 [561]metres; CON: 3273 [458]metres) and CON conditions, accumulated more B(lac), but did not increase their peak RPE rating (p < 0.05). The M intervention improved tolerance of high intensity exercise in warm conditions. It was proposed that a change in attentional processing from internal (physical sensations) to external perspective (music and video) may have facilitated this improvement. These findings have strong implications for improving health, fitness and engagement in gym-based exercise programs. Key pointsThe study examined the ergogenic effect of a motivational (M) video and music intervention on high-intensity exercise performance in comparison to a non-motivational (NM) condition and a control (CON).PARTICIPANTS IN THE M CONDITION RAN SIGNIFICANTLY FURTHER THAN IN THE NM (M: 3524 [388]metres; NM: 3110 [561]metres; CON: 3273 [458]metres) and CON conditions, accumulated more B(lac), but did not increase their peak RPE rating (p < 0.05).It was proposed that a change in attentional processing from internal (physical sensations) to external perspective (music and video) may have facilitated this improvement.These findings have strong implications for improving health, fitness and engagement in gym-based exercise programs.

15.
Eye Contact Lens ; 34(4): 201-6, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18787426

RESUMO

PURPOSE: To determine if the discomfort associated with pterygium is different for men and women. METHODS: Subjects were selected from patients attending a clinic in Guanajuato, Mexico, which has a high prevalence of pterygium. Discomfort was determined using a Spanish version of an English questionnaire designed to evaluate symptoms in dry eye patients. Questions were asked regarding seven sensations of discomfort, and five environmental sources of irritation that were not present in the original questionnaire: smoke, cigarette smoke, dust, wind, and sun. Most of the subjects had limited reading skills so the questionnaire was administered orally. Two subsamples are reported. In the first subsample, the interviewer was a male interviewer and the subsample was made up of 28 matched pairs of subjects selected from a total of 110 subjects (one man and one woman in each pair with the same age and pterygium stage). In the second subsample, the interviewer was a female interviewer and made up of 16 matched pairs selected from a total of 70 subjects. Pterygium staging was based on a scale in which progression was staged on a scale of one to five. The data was analyzed statistically using the Mann-Whitney U test (two-tailed). RESULTS: The subjects had an age range of 41 to 82 years. The pterygium stages ranged from localized minor disturbances of the nasal conjunctiva (one on the scale) to compound pterygium (five on the scale). The difference in ocular surface discomfort between men and women was statistically significant for both the male interviewer (P < 0.001) and the female interviewer (P < 0.01). CONCLUSIONS: Women with pterygium report more discomfort than men. It is likely that men and women with other sources of ocular surface discomfort also respond differently to pain.


Assuntos
Dor/fisiopatologia , Pterígio/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Inquéritos e Questionários
16.
Cancer Res ; 68(8): 2652-60, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18413732

RESUMO

Ribonucleotide reductase (RNR) catalyzes the rate-limiting step in nucleotide biosynthesis and plays a central role in genome maintenance. Although a number of regulatory mechanisms govern RNR activity, the physiologic effect of RNR deregulation had not previously been examined in an animal model. We show here that overexpression of the small RNR subunit potently and selectively induces lung neoplasms in transgenic mice and is mutagenic in cultured cells. Combining RNR deregulation with defects in DNA mismatch repair, the cellular mutation correction system, synergistically increased RNR-induced mutagenesis and carcinogenesis. Moreover, the proto-oncogene K-ras was identified as a frequent mutational target in RNR-induced lung neoplasms. Together, these results show that RNR deregulation promotes lung carcinogenesis through a mutagenic mechanism and establish a new oncogenic activity for a key regulator of nucleotide metabolism. Importantly, RNR-induced lung neoplasms histopathologically resemble human papillary adenocarcinomas and arise stochastically via a mutagenic mechanism, making RNR transgenic mice a valuable model for lung cancer.


Assuntos
Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Ribonucleotídeo Redutases/genética , Células 3T3 , Animais , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Éxons , Genes ras , Neoplasias Pulmonares/enzimologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Mutação , Proto-Oncogene Mas
17.
Chem Biol Drug Des ; 70(3): 227-36, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17718717

RESUMO

The aim of this work was to design and utilize a bifunctional peptide inhibitor called glutamic acid decarboxylase-bifunctional peptide inhibitor to suppress the progression of type 1 diabetes in non-obese diabetic mice. The hypothesis is that glutamic acid decarboxylase-bifunctional peptide inhibitor binds simultaneously to major histocompatibility complex-II and intercellular adhesion molecule type 1 on antigen-presenting cell and inhibits the immunological synapse formation during T-cell-antigen-presenting cell interactions. Glutamic acid decarboxylase-bifunctional peptide inhibitor was composed of a major epitope of the type 1 diabetes-associated antigen, glutamic acid decarboxylase 65 kDa, covalently linked to a peptide derived from CD11a of lymphocyte function-associated antigen-1. The suppression of insulitis and type 1 diabetes was evaluated using non-obese diabetic and non-obese diabetic severe combined immunodeficiency mice. Glutamic acid decarboxylase-bifunctional peptide inhibitor had the capacity to suppress invasive insulitis in non-obese diabetic mice. CD4+ T-cells isolated from glutamic acid decarboxylase-bifunctional peptide inhibitor treated mice also suppressed insulitis and hyperglycemia when transferred with diabetogenic non-obese diabetic spleen cells into non-obese diabetic severe combined immunodeficiency recipients. As predicted, the glutamic acid decarboxylase-bifunctional peptide inhibitor cross-linked a significant fraction of major histocompatibility complex class-II molecules to intercellular adhesion molecule type 1 molecules on the surface of live antigen-presenting cell. Intravenous injection of the glutamic acid decarboxylase-bifunctional peptide inhibitor elicited interleukin-4-producing T-cells in non-obese diabetic mice primed against the glutamic acid decarboxylase-epitope peptide. Together, the results indicate that glutamic acid decarboxylase-bifunctional peptide inhibitor induces interleukin-4-producing regulatory cells but does not expand the glutamic acid decarboxylase-specific Th2 population. Given that Th2 effector cells can cause pathology, the glutamic acid decarboxylase-bifunctional peptide inhibitor may represent a novel mechanism to induce interleukin-4 without Th2-associated pathology.


Assuntos
Células Apresentadoras de Antígenos/efeitos dos fármacos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Peptídeos/química , Peptídeos/farmacologia , Linfócitos T/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Células Apresentadoras de Antígenos/citologia , Células Apresentadoras de Antígenos/imunologia , Diabetes Mellitus Tipo 1/enzimologia , Diabetes Mellitus Tipo 1/patologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/uso terapêutico , Feminino , Glutamato Descarboxilase/antagonistas & inibidores , Glutamato Descarboxilase/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Dados de Sequência Molecular , Transdução de Sinais , Linfócitos T/citologia , Linfócitos T/imunologia
18.
Genetics ; 175(2): 777-83, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17110486

RESUMO

In Drosophila melanogaster, seminal fluid regulates the reproductive and immune responses of mated females. Some seminal fluid proteins may provide protective functions to mated females, such as antimicrobial activity and/or stimulation of antimicrobial gene expression levels, while others appear to have negative effects, contributing to a "cost of mating." To identify seminal proteins that could participate in these phenomena, we used a systemic ectopic expression screen to test the effects on unmated females of proteins normally produced by the male accessory gland (Acps). Of the 21 ectopically expressed Acps that we tested for ability to assist in the clearance of a bacterial infection with Serratia marcescens, 3 Acps significantly reduced the bacterial counts of infected females, suggesting a protective role. Of the 23 Acps that we tested for toxicity, 3 were toxic, including one that has been implicated in the cost of mating in another study. We also tested ectopic expression females for other Acp-induced effects, but found no additional Acps that affected egg laying or receptivity upon ectopic expression.


Assuntos
Proteínas de Drosophila/farmacologia , Proteínas de Drosophila/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Expressão Gênica , Proteínas de Plasma Seminal/farmacologia , Proteínas de Plasma Seminal/toxicidade , Animais , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/microbiologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Oviposição/efeitos dos fármacos , Proteínas de Plasma Seminal/genética , Proteínas de Plasma Seminal/metabolismo , Infecções por Serratia , Serratia marcescens/efeitos dos fármacos , Serratia marcescens/crescimento & desenvolvimento , Abstinência Sexual/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos
19.
J Am Coll Health ; 54(5): 295-300, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16539222

RESUMO

Researchers in the social norms area have previously focused primarily on alcohol consumption, paying comparatively less attention to drug use and sexual behavior. The major purposes of this study were to (1) compare perceptions of peer norms in the areas of alcohol use, drug use, and sexual behavior with actual behavior and (2) determine if a relationship existed between a student's perceptions of normative behavior and a student's actual behavior. Participants were 833 college students at a large, public university in the Northeast. Study participants overestimated alcohol use, drug use, and sexual behavior among their peers. There was also a positive relationship between actual behavior and perceived peer norms, although the effect sizes for all behaviors were small to moderate. The authors provide further support for the tenets of social norms theory and suggest that social norms interventions are appropriate both campus-wide and to targeted high-risk groups.


Assuntos
Transtornos Relacionados ao Uso de Álcool/epidemiologia , Comportamento Sexual/psicologia , Conformidade Social , Percepção Social , Estudantes/psicologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Universidades , Adolescente , Adulto , Transtornos Relacionados ao Uso de Álcool/etnologia , Cultura , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New England , Medição de Risco , Comportamento Sexual/etnologia , Sociologia Médica , Estudantes/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/etnologia , Inquéritos e Questionários
20.
Psychol Addict Behav ; 18(4): 390-3, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15631613

RESUMO

Prior research has examined a number of individual characteristics (e.g., gender, family connectedness) that protect individuals from engaging in heavy drinking and experiencing negative alcohol-related consequences, but less is known about specific behavioral strategies that might also serve as protective factors. In this study, 556 undergraduate students completed the National College Health Assessment (American College Health Association, 2000) and answered questions regarding the use of specific protective behavioral strategies (PBS), alcohol consumption, and alcohol-related consequences. Results indicated that less frequent use of PBS was related to a greater likelihood of experiencing negative alcohol-related consequences, even after accounting for the effects of gender and alcohol consumption. These results suggest that PBS may be an important component of both prevention and treatment programs for college students.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Mecanismos de Defesa , Grupo Associado , Estudantes/psicologia , Universidades , Adulto , Tomada de Decisões , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Razão de Chances , Comportamento Sexual/psicologia , Violência/psicologia
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