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1.
Coral Reefs ; 42(2): 359-366, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37009568

RESUMO

We study the microbiome of sea water collected from two locations of the Barbadian coral reefs. The two sites differ in several environmental and ecological variables including their endogenous benthic community and their proximity to urban development and runoffs from inland watersheds. The composition of the microbial communities was estimated using whole genome DNA shotgun sequencing with adjuvant measurements of chemical and environmental qualities. Although both sites exhibit a similar degree of richness, the less urbanized site (Maycocks reef at Hangman's Bay) has a strong concentration of phototrophs whereas the more urbanized location (Bellairs reef at Folkstone) is enriched for copiotrophs, macroalgal symbionts and marine-related disease-bearing organisms from taxa scattered across the tree of life. Our results are concordant with previous profiles of warm ocean surface waters, suggesting our approach captures the state of each coral reef site, setting the stage for longitudinal studies of marine microbiome dynamics in Barbados. Supplementary Information: The online version contains supplementary material available at 10.1007/s00338-022-02330-y.

2.
Breast Cancer Res Treat ; 183(3): 677-682, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32696314

RESUMO

PURPOSE: Radial scars and complex sclerosing lesions of the breast are part of a group of "indeterminate" breast lesions, which are excised due to risk of coexistent carcinoma. The aim of this study was to assess rate of upgrade of these lesions to invasive and in situ carcinoma and to quantify the risk of development of subsequent cancer in women diagnosed with these lesions. METHODS: A retrospective review of a prospectively maintained breast screening database was performed. All patients with radial scar identified at either core biopsy or final excision biopsy between January 2006 and July 2012 were identified. Full pathological reports for both core biopsy and final excision biopsy were reviewed. Patient outcomes were followed for a mean of 117.1 months. RESULTS: Of 451 B3 biopsies performed at our screening unit, 95 (22%) were found to have a radial scar or complex sclerosing lesion (CSL) on core needle biopsy. Within this group, 77 had no atypia on CNB, with 7 (9%) upgraded to invasive/in situ carcinoma on final excision. Of nine with definite atypia on CNB, 3 (33%) were upgraded. In those patients without atypia or malignancy on final excision, 7.5% developed cancer during 10-year follow-up. CONCLUSION: Patients with radial scar with atypia have a higher risk of upgrade to malignancy. Further research is needed to identify which patients may safely avoid excision of radial scar. Patients with a diagnosis of radial scar on CNB are at increased subsequent risk of breast cancer and may benefit from additional screening.


Assuntos
Neoplasias da Mama , Cicatriz , Biópsia com Agulha de Grande Calibre , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Cicatriz/diagnóstico , Cicatriz/epidemiologia , Cicatriz/etiologia , Feminino , Humanos , Estudos Retrospectivos
3.
Ir J Med Sci ; 186(1): 1-16, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28133714

RESUMO

BACKGROUND: The physical form of the hospital environment shapes the care setting and influences the relationship of the hospital to the community. Due to ongoing demographic change, evolving public health needs, and advancing medical practice, typical hospitals are frequently redeveloped, retrofitted, or expanded. It is argued that multi-disciplinary and multi-stakeholder approaches are required to ensure that hospital design matches these increasingly complex needs. To facilitate such a conversation across different disciplines, experts, and community stakeholders, it is helpful to establish a hospital typology and associated terminology as part of any collaborative process. AIMS: Examine the literature around hospital design, and review the layout and overall form of a range of typical Irish acute public hospitals, to outline an associated building typology, and to establish the terminology associated with the planning and design of these hospitals in Ireland. METHODS: Searches in 'Academic Search Complete', 'Compendex', 'Google', 'Google Scholar', 'JSTOR', 'PADDI', 'Science Direct', 'Scopus', 'Web of Science', and Trinity College Dublin Library. The search terms included: 'hospital design history'; 'hospital typology'; 'hospital design terminology'; and 'hospital design Ireland'. RESULTS: Typical hospitals are composed of different layouts due to development over time; however, various discrete building typologies can still be determined within many hospitals. This paper presents a typology illustrating distinct layout, circulation, and physical form characteristics, along with a hospital planning and design terminology of key terms and definitions. CONCLUSION: This typology and terminology define the main components of Irish hospital building design to create a shared understanding around design, and support stakeholder engagement, as part of any collaborative design process.


Assuntos
Comportamento Cooperativo , Hospitais , Terminologia como Assunto , Humanos , Irlanda
5.
Clin Toxicol (Phila) ; 52(5): 490-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24716792

RESUMO

BACKGROUND AND PURPOSE: Hydrogen sulfide (H2S) is a highly toxic gas for which no effective antidotes exist. It acts, at least in part, by binding to cytochrome c oxidase, causing cellular asphyxiation and anoxia. We investigated the effects of three different ligand forms of cobinamide, a vitamin B12 analog, to reverse sulfide (NaHS) toxicity. METHODS: New Zealand white rabbits received a continuous intravenous (IV) infusion of NaHS (3 mg/min) until expiration or a maximum 270 mg dose. Animals received six different treatments, administered at the time when they developed signs of severe toxicity: Group 1-saline (placebo group, N = 9); Group 2--IV hydroxocobalamin (N = 7); Group 3--IV aquohydroxocobinamide (N = 6); Group 4--IV sulfitocobinamide (N = 6); Group 5--intramuscular (IM) sulfitocobinamide (N = 6); and Group 6-IM dinitrocobinamide (N = 8). Blood was sampled intermittently, and systemic blood pressure and deoxygenated and oxygenated hemoglobin were measured continuously in peripheral muscle and over the brain region; the latter were measured by diffuse optical spectroscopy (DOS) and continuous wave near infrared spectroscopy (CWNIRS). RESULTS: Compared with the saline controls, all cobinamide derivatives significantly increased survival time and the amount of NaHS that was tolerated. Aquohydroxocobinamide was most effective (261.5 ± 2.4 mg NaHS tolerated vs. 93.8 ± 6.2 mg in controls, p < 0.0001). Dinitrocobinamide was more effective than sulfitocobinamide. Hydroxocobalamin was not significantly more effective than the saline control. CONCLUSIONS: Cobinamide is an effective agent for inhibiting lethal sulfide exposure in this rabbit model. Further studies are needed to determine the optimal dose and form of cobinamide and route of administration.


Assuntos
Antídotos/farmacologia , Cobamidas/farmacologia , Sulfeto de Hidrogênio/intoxicação , Hidroxocobalamina/farmacologia , Sulfetos/intoxicação , Animais , Antídotos/administração & dosagem , Antídotos/química , Cobamidas/administração & dosagem , Cobamidas/química , Modelos Animais de Doenças , Hemoglobinas/metabolismo , Sulfeto de Hidrogênio/administração & dosagem , Hidroxocobalamina/administração & dosagem , Infusões Intravenosas , Injeções Intramusculares , Injeções Intravenosas , Coelhos , Espectroscopia de Luz Próxima ao Infravermelho , Taxa de Sobrevida
6.
Eur J Neurol ; 20(8): 1135-44, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23384428

RESUMO

BACKGROUND AND PURPOSE: Enzogenol, a flavonoid-rich extract from Pinus radiata bark with antioxidant and anti-inflammatory properties has been shown to improve working memory in healthy adults. In traumatic brain injury (TBI), oxidation and inflammation have been linked to poorer cognitive outcomes. Hence, this phase II, randomized controlled trial investigated safety, compliance and efficacy of Enzogenol for improving cognitive functioning in people following mild TBI. METHODS: Sixty adults, who sustained a mild TBI, 3-12 months prior to recruitment, and who were experiencing persistent cognitive difficulties [Cognitive Failures Questionnaire (CFQ) score > 38], were randomized to receive Enzogenol (1000 mg/day) or matching placebo for 6 weeks. Subsequently, all participants received Enzogenol for a further 6 weeks, followed by placebo for 4 weeks. Compliance, side-effects, cognitive failures, working and episodic memory, post-concussive symptoms and mood were assessed at baseline, 6, 12 and 16 weeks. Simultaneous estimation of treatment effect and breakpoint was effected, with confidence intervals (CIs) obtained through a treatment-placebo balance-preserving bootstrap procedure. RESULTS: Enzogenol was found to be safe and well tolerated. Trend and breakpoint analyses showed a significant reduction in cognitive failures after 6 weeks [mean CFQ score, 95% CI, Enzogenol versus placebo -6.9 (-10.8 to -4.1)]. Improvements in the frequency of self-reported cognitive failures were estimated to continue until week 11 before stabilizing. Other outcome measures showed some positive trends but no significant treatment effects. CONCLUSIONS: Enzogenol supplementation is safe and well tolerated in people after mild TBI, and may improve cognitive functioning in this patient population. This study provides Class IIB evidence that Enzogenol is well tolerated and may reduce self-perceived cognitive failures in patients 3-12 months post-mild TBI.


Assuntos
Lesões Encefálicas/complicações , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/etiologia , Suplementos Nutricionais , Flavonoides/uso terapêutico , Quercetina/análogos & derivados , Acidentes de Trânsito , Adulto , Lesões Encefálicas/psicologia , Transtornos Cognitivos/psicologia , Interpretação Estatística de Dados , Método Duplo-Cego , Feminino , Flavonoides/efeitos adversos , Escala de Coma de Glasgow , Humanos , Masculino , Memória/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Dinâmica não Linear , Cooperação do Paciente , Projetos Piloto , Síndrome Pós-Concussão/tratamento farmacológico , Síndrome Pós-Concussão/psicologia , Quercetina/efeitos adversos , Quercetina/uso terapêutico , Resultado do Tratamento , Adulto Jovem
10.
Anaesthesia ; 56(9): 829-35, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11531666

RESUMO

Xenon anaesthesia is thought to have minimal haemodynamic side-effects. It is, however, expensive and requires special delivery systems for economic use. In this randomised cross-over study, we: (i) investigated the haemodynamic profile and recovery characteristics of xenon compared with propofol sedation in postoperative cardiac surgery patients, and (ii) evaluated a fully closed breathing system to minimise xenon consumption. We demonstrated a significantly faster recovery from xenon (3 min 11 s) than propofol sedation (25 min 23 s). Relative to propofol, xenon sedation produced no change in heart rate or mean arterial pressure and there were significantly higher mean values for central venous pressure (10.6 vs. 8.9 mmHg), pulmonary artery occlusion pressure (11.2 vs. 9.5 mmHg), mean pulmonary artery pressure (20.1 vs. 18.3 mmHg) and systemic vascular resistance index (2170 vs. 1896 dyn.s.cm-5.m-2). The haemodynamic profile seen with propofol reflected its known vasodilator effects. This was supported by the almost identical left ventricular stroke work indexes seen with both methods of sedation.


Assuntos
Anestésicos Inalatórios/farmacologia , Sedação Consciente/métodos , Ponte de Artéria Coronária , Hemodinâmica/efeitos dos fármacos , Xenônio/farmacologia , Idoso , Anestesia com Circuito Fechado/métodos , Anestésicos Intravenosos/farmacologia , Estudos Cross-Over , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios/métodos , Propofol/farmacologia
11.
J Neurosci ; 21(17): 6874-88, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11517275

RESUMO

The cerebral cortex provides a major source of inputs to the basal ganglia. As has been well documented, the topography of corticostriatal projections subdivides the striatum into a mosaic of functionally distinct sectors. How information flow from these striatal sectors remains segregated or not within basal ganglia output nuclei has to be established. Electrophysiologically identified neurons of the rat substantia nigra pars reticulata were labeled by juxtacellular injection of Neurobiotin, and the spatial organization of their dendritic arborizations was analyzed in relation to the projection fields of individual striatal sectors. Thirty-nine nigral neurons located in the projection territory of the distinct striatal sensorimotor sectors were reconstructed. The data show that the dendritic arborizations of nigral neurons conform to the geometry of striato-nigral projections. Like striatal projections, the arborizations formed a series of curved laminas enveloping a dorsolaterally located core. Although dendritic fields of the neurons lying in the laminae were flat, those located in the core were spherical or cylindrical, thereby conforming to the shape of the striatal projection fields. This remarkable alignment between the dendritic arborizations of nigral neurons and the projection fields from individual striatal districts supports the concept of a parallel architecture of the striato-nigral circuits. However, pars reticulata neurons usually extend part of their dendrites within adjacent striatal projection fields, thereby ensuring a continuum between channels. The extension of the dendritic arborizations within the striatal projection fields suggests that nigral neurons integrate the information that is relevant for the completion of the specific motor behavior they control.


Assuntos
Biotina/análogos & derivados , Corpo Estriado/anatomia & histologia , Dendritos , Vias Neurais/anatomia & histologia , Neurônios/citologia , Substância Negra/anatomia & histologia , Potenciais de Ação/fisiologia , Animais , Biotina/administração & dosagem , Biotina/farmacocinética , Estimulação Elétrica , Imageamento Tridimensional , Iontoforese , Masculino , Microinjeções , Neurônios/classificação , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley
13.
Med Pediatr Oncol ; 36(5): 583-91, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11340616

RESUMO

BACKGROUND: Children treated with radiotherapy to the neck or exposed to environmental radiation are at risk for developing thyroid cancer later in life. The best method for screening these high-risk patients is unclear. We systematically reviewed evidence on the accuracy of ultrasound and palpation to detect thyroid nodules and of fine needle aspiration (FNA), a confirmatory test, to diagnose thyroid cancer. PROCEDURE: We searched the MEDLINE database for papers published since 1966, using the MeSH term thyroid neoplasms and terms related to diagnostic test performance. To supplement our MEDLINE searches, we searched reference lists from recent reviews and articles recommended by thyroid cancer experts. We recorded the tests used, the gold standard determination of disease, the test performance results, and the presence of biases that could affect the reported results. We also abstracted the number of patients who underwent surgery and the final diagnoses. We created two decision models: one for screening 10,000 medically irradiated patients, and one for screening 10,000 environmentally irradiated patients. RESULTS: Using ultrasound as the gold standard determination of the presence of a nodule, the sensitivity of palpation for all sized nodules was 10-41 percent, indicating that a high proportion of nodules detected by ultrasound are too small to be palpated. Sensitivity of palpation increased with nodule size. The specificity of palpation ranged from 95 to 100%. In studies from referral centers, the reported sensitivity and specificity of FNA were 71-95 and 52-99%, respectively. However, most authors excluded the proportion of patients (6-33%) who had inadequate or nondiagnostic FNA results when calculating sensitivity and specificity, even though 6-100% of these patients went on to have a diagnostic lobectomy. When each study was reanalyzed so that patients with nondiagnostic FNA results who went directly to surgery were reclassified as positive tests, sensitivity increased slightly, but specificity dropped by 4-20 percentage points per study. The decision model for screening 10,000 medically irradiated patients revealed that if ultrasound were used as an initial screen, 2,741 patients would have nodules at least 1 cm in size; assuming no patients with smaller nodules had surgery, 1,964 patients would have surgery; 275 patients would have a diagnosis of thyroid cancer. Screening with ultrasound as an initial test would detect an additional 150 cases of thyroid cancer compared to those screened with palpation. However, an additional 1,689 patients would have surgery for nonmalignant nodules (compared to 480 patients with nonmalignant nodules screened with palpation). The yield for screening 10,000 environmentally irradiated patients was several times smaller than for screening 10,000 medically irradiated patients. If 10,000 environmentally irradiated patients were screened initially with ultrasound, approximately 708 patients would have nodules at least 1 cm in size; 89 patients would have surgery; and 38 patients would be diagnosed with thyroid cancer. CONCLUSIONS: Regardless of type of exposure, testing initially with ultrasound detects several times more cases of thyroid cancer than palpation. However, when ultrasound is the initial test, many more patients also have surgery for nonmalignant nodules. Screening with palpation is not very reassuring, particularly to medically irradiated patients with negative tests, since almost half (46%) of these patients may have undetected nodules.


Assuntos
Programas de Rastreamento/normas , Neoplasias da Glândula Tireoide/diagnóstico , Técnicas de Apoio para a Decisão , Humanos , Neoplasias Induzidas por Radiação/diagnóstico , Palpação/normas , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia
14.
Am J Prev Med ; 20(3 Suppl): 47-58, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11306232

RESUMO

CONTEXT: Malignant melanoma is often lethal, and its incidence in the United States has increased rapidly over the past 2 decades. Nonmelanoma skin cancer is seldom lethal, but, if advanced, can cause severe disfigurement and morbidity. Early detection and treatment of melanoma might reduce mortality, while early detection and treatment of nonmelanoma skin cancer might prevent major disfigurement and to a lesser extent prevent mortality. Current recommendations from professional societies regarding screening for skin cancer vary. OBJECTIVE: To examine published data on the effectiveness of routine screening for skin cancer by a primary care provider, as part of an assessment for the U.S. Preventive Services Task Force. DATA SOURCES: We searched the MEDLINE database for papers published between 1994 and June 1999, using search terms for screening, physical examination, morbidity, and skin neoplasms. For information on accuracy of screening tests, we used the search terms sensitivity and specificity. We identified the most important studies from before 1994 from the Guide to Clinical Preventive Services, second edition, and from high-quality reviews. We used reference lists and expert recommendations to locate additional articles. STUDY SELECTION: Two reviewers independently reviewed a subset of 500 abstracts. Once consistency was established, the remainder were reviewed by one reviewer. We included studies if they contained data on yield of screening, screening tests, risk factors, risk assessment, effectiveness of early detection, or cost effectiveness. DATA EXTRACTION: We abstracted the following descriptive information from full-text published studies of screening and recorded it in an electronic database: type of screening study, study design, setting, population, patient recruitment, screening test description, examiner, advertising targeted at high-risk groups or not targeted, reported risk factors of participants, and procedure for referrals. We also abstracted the yield of screening data including probabilities and numbers of referrals, types of suspected skin cancers, biopsies, confirmed skin cancers, and stages and thickness of skin cancers. For studies that reported test performance, we recorded the definition of a suspicious lesion, the "gold-standard" determination of disease, and the number of true positive, false positive, true negative, and false negative test results. When possible, positive predictive values, likelihood ratios, sensitivity, and specificity were recorded. DATA SYNTHESIS: No randomized or case-control studies have been done that demonstrate that routine screening for melanoma by primary care providers reduces morbidity or mortality. Basal cell carcinoma and squamous cell carcinoma are very common, but detection and treatment in the absence of formal screening are almost always curative. No controlled studies have shown that formal screening programs will improve this already high cure rate. While the efficacy of screening has not been established, the screening procedures themselves are noninvasive, and the follow-up test, skin biopsy, has low morbidity. Five studies from mass screening programs reported the accuracy of skin examination as a screening test. One of these, a prospective study, tracked patients with negative results to determine the number of patients with false-negative results. In this study, the sensitivity of screening for skin cancer was 94% and specificity was 98%. Several recent case-control studies confirm earlier evidence that risk of melanoma rises with the presence of atypical moles and/or many common moles. One well-done prospective study demonstrated that risk assessment by limited physical exam identified a relatively small (<10%) group of primary care patients for more thorough evaluation. CONCLUSIONS: The quality of the evidence addressing the accuracy of routine screening by primary care providers for early detection of melanoma or nonmelanoma skin cancer ranged from poor to fair. We found no studies that assessed the effectiveness of periodic skin examination by a clinician in reducing melanoma mortality. Both self-assessment of risk factors or clinician examination can classify a small proportion of patients as at highest risk for melanoma. Skin cancer screening, perhaps using a risk-assessment technique to identify high-risk patients who are seeing a physician for other reasons, merits additional study as a strategy to address the excess burden of disease in older adults.


Assuntos
Carcinoma Basocelular/prevenção & controle , Carcinoma de Células Escamosas/prevenção & controle , Programas de Rastreamento , Melanoma/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Medicina Baseada em Evidências , Humanos , Avaliação de Processos e Resultados em Cuidados de Saúde , Valor Preditivo dos Testes , Atenção Primária à Saúde , Estados Unidos
15.
Am J Prev Med ; 20(3 Suppl): 62-72, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11306234

RESUMO

CONTEXT: Bacterial vaginosis (BV) is a strong independent risk factor for adverse pregnancy outcomes. BV is found in 9% to 23% of pregnant women. Symptoms include vaginal discharge, pruritus, or malodor, but often women with BV are asymptomatic. OBJECTIVES: To determine whether screening and treating pregnant women for BV reduces adverse pregnancy outcomes, as part of an assessment for the U.S. Preventive Services Task Force. DATA SOURCES: Randomized clinical trials of BV treatment in pregnancy that measured pregnancy outcomes were identified from multiple searches in MEDLINE from 1966 to 1999, the Cochrane Controlled Trials Register and Library, and national experts. STUDY SELECTION: All randomized controlled trials of BV treatment in pregnancy that specifically measured pregnancy outcomes. DATA EXTRACTION: The following information was abstracted: study design and blinding, diagnostic methods, antibiotic interventions, timing of antibiotic treatment in pregnancy, criteria for treatment, comorbidities, demographic details, risk factors for preterm delivery such as previous preterm delivery, compliance, rates of spontaneous and total preterm delivery less than 37 weeks and less than 34 weeks, preterm premature rupture of membranes, low birth weight less than 2500 grams, spontaneous abortion, postpartum endometritis, and neonatal sepsis. For each study, we measured the effect of treatment by calculating the difference in the rate of a given pregnancy outcome in the control group minus the treatment group (the absolute risk reduction [ARR]). A stepwise procedure based on the profile likelihood was applied to assess heterogeneity, to pool studies when appropriate, and to calculate the mean and 90% confidence intervals (CIs) for the effect of treatment. DATA SYNTHESIS: Seven randomized controlled trials met inclusion criteria for the meta-analysis. We found no benefit to BV treatment in average-risk women for any pregnancy outcome. Results of studies of high-risk populations, women with previous preterm delivery, were statistically heterogeneous. They clustered into two groups; one showed no benefit (ARR=-0.08, 90% CI=-0.19 to 0.04), whereas the three homogeneous studies showed potential benefit of BV treatment (pooled ARR=0.22; 90% CI=0.13 to 0.31) for preterm delivery before 37 weeks. Four high-risk studies reported results for preterm delivery less than 34 weeks. The pooled estimate showed no benefit (ARR=0.04; 90% CI=-0.02 to 0.09), but variation was noted among individual studies. Two trials of high-risk women found an increase in preterm delivery less than 34 weeks in women who did not have BV but received BV treatment. Comparisons of patient populations, treatment regimens, and study designs did not explain the heterogeneity among studies. CONCLUSIONS: We found no benefit to routine BV screening and treatment. A subgroup of high-risk women may benefit from BV screening and treatment; however, there may be a subgroup for whom BV treatment could increase the occurrence of preterm delivery.


Assuntos
Programas de Rastreamento , Complicações Infecciosas na Gravidez/prevenção & controle , Diagnóstico Pré-Natal , Vaginose Bacteriana/prevenção & controle , Feminino , Humanos , Recém-Nascido , Trabalho de Parto Prematuro/prevenção & controle , Gravidez , Resultado da Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Risco
16.
Cereb Cortex ; 11(4): 360-73, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11278199

RESUMO

The functions of the basal ganglia are achieved through excitation of striatal output neurons (SONs) by converging cortical glutamergic afferents. We assessed the relationship between different patterns of activity in cortico-striatal (C-S) cells and the electrical behavior of SONs in vivo. Intracellular activities of rat C-S neurons in the orofacial motor cortex and of SONs, located in the projection field of this cortical region, were recorded under different anesthetics, which generate various temporal patterns of cortical activity. A surface electroencephalogram (EEG) of the orofacial motor cortex was simultaneously performed with intracellular recordings and EEG waves were used as correlates of a coherent synaptic activity in cortical neurons. Under barbiturate anesthesia C-S neurons showed rhythmic (5--7 Hz) supra-threshold depolarizations in phase with large amplitude EEG waves. The correlative activity of SONs was characterized by large amplitude oscillation-like synaptic depolarizations that could trigger action potentials. Under ketamine-xylazine anesthesia C-S neurons exhibited a step-like behavior consisting of depolarizing plateaus (up states), leading to multiple spike discharges, interrupted by hyperpolarizing periods (down states). The related activity of SONs was step-like membrane potential fluctuations with firing confined to the early part of the striatal up state. In C-S neurons and SONs up states coincided with slow recurrent EEG waves (approximately 1 Hz). Finally, under neurolept-analgesia an apparently disorganized EEG activity was associated with a lack of rhythmic discharge in C-S neurons. This uncorrelated activity in C-S neurons resulted in an absence of spontaneous firing as well as of large amplitude synaptic depolarizations in SONs. In the present study we demonstrate that SONs shape their input-output relationship by filtering out uncorrelated synaptic activity and that a minimal synchronization in the cortico-striatal afferents is required to produce significant synaptic depolarization in SONs.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Agonistas alfa-Adrenérgicos/farmacologia , Anestésicos Dissociativos/farmacologia , Corpo Estriado/efeitos dos fármacos , Eletroencefalografia/efeitos dos fármacos , Hipnóticos e Sedativos/farmacologia , Córtex Motor/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Corpo Estriado/fisiologia , Ketamina/farmacologia , Masculino , Córtex Motor/fisiologia , Neuroleptanalgesia , Neurônios/fisiologia , Neurônios Eferentes/efeitos dos fármacos , Neurônios Eferentes/fisiologia , Ratos , Ratos Sprague-Dawley , Xilazina/farmacologia
17.
Clin J Oncol Nurs ; 5(3): 105-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11899367

RESUMO

Advances in the area of cancer prevention and early detection are being made constantly. Basic epidemiologic research continues to provide insight into the impact of carcinogen exposure and the development of cancer. It is exciting to note that the study of Tamoxifen and Raloxifene chemoprevention trial is successfully recruiting women, including minority women, to participate. This large chemoprevention trial is providing much insight into how to recruit and retain women to take a chemoprevention agent to ultimately prevent the development of cancer. Advances also are being made in the knowledge base of how to best detect cancer in asymptomatic people. The best screening tool recommendation for the early detection of colorectal cancer remains controversial. Screening for colorectal cancer, however, is the only way to ultimately decrease the morbidity and mortality associated with the disease. Oncology nurses need to accurately risk for colorectal cancer and provide patients with the necessary information to make an informed choice about the most appropriate screening for their situation. Oncology nurses need to be familiar with new research and advances in cancer prevention and early detection so they can share information with patients and their families.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/prevenção & controle , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Colonoscopia , Moduladores de Receptor Estrogênico/administração & dosagem , Humanos , Cloridrato de Raloxifeno/administração & dosagem , Tamoxifeno/administração & dosagem
18.
Clin J Oncol Nurs ; 5(3): 117-20, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11899370

RESUMO

Both of the articles reviewed here as well as the references, suggest that very little is actually known about the impact of many aspects of genetic testing. How decision are made about genetic testing in people who do not have cancer, how the results of testing are used used to guide care, and ultimately how people adjust to prophylactic surgery, which is the most effective form of prevention currently available to those who do have a mutation are not completely clear. This has many implications for practice in general. Oncology nurses who build relationships with those diagnosed with cancer and their families may be one of the best groups of professionals to provide the education and counseling individuals and families need prior to making any decision about genetic testing. Just as many responses to cancer exist, so do many responses to finding out the results of mutation status. Oncology nurses are challenged to help facilitate adjustment to learning that one carries a mutation that significantly increases risk of developing cancer. More nursing research needs to be conducted on how to facilitate this adjustment. Dealing with the unknown can be a frightening experience. Little is known about the long-term effectiveness of prophylactic mastectomy and oophorectomy in unaffected mutation-positive individuals. Most of what is known is based on retrospective review. Nurses are challenged to interpret this information, along with its inherent strengths and weaknesses, to individuals so they can make the best possible decisions. The psychosocial needs of those who undergo prophylactic surgery are not clearly understood. Surgery can have many psychological outcomes, and how individuals adjust to these changes is not clear. More nursing research is needed not only to understand these needs but also to design interventions to facilitate and improve adjustment to not only the information that one is mutation positive but also to prophylactic surgery. People who do not have cancer but have a high risk for cancer because of their genetic background need comprehensive and consistent care by knowledgeable healthcare providers. Although these individuals have not been diagnosed with cancer, they have complex psychosocial needs related to their family history and the decisions being made about prevention strategies. Oncology nurses can help fill this gap in care and provide the necessary support these individuals need.


Assuntos
Neoplasias da Mama/cirurgia , Tomada de Decisões , Testes Genéticos , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias da Mama/prevenção & controle , Genes BRCA1 , Predisposição Genética para Doença , Humanos , Mastectomia
20.
J R Coll Physicians Lond ; 34(5): 448-51, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11077656

RESUMO

UNLABELLED: We have investigated bile acid malabsorption (BAM), and its response to treatment, in patients seen in this district general hospital with chronic continuous or recurrent diarrhoea. METHODS: Seven-day retention of 75-SeHCAT was measured (normal: > 10%). TREATMENT: Patients were initially given conventional therapy (prednisolone +/- ASA drugs in Crohn's disease, and antidiarrhoeals in the others). If this therapy failed, bile acid sequestrants (BAS) were prescribed. The definition of successful response was based on the patient's perception of sustained improvement. PATIENTS: The 304 patients were categorised as follows: Group 1: Crohn's disease patients with ileal resection, in clinical remission (n = 37). Group 2: Crohn's disease, unoperated and in clinical remission (n = 44). Group 3: vagotomy and pyloroplasty, with/without cholecystectomy (n = 26). Group 4: diarrhoea predominant 'irritable bowel syndrome' (IBS) (n = 197). RESULTS: BAM was found in 97% (36/37), 54% (24/44) and 58% (15/26) of patients in groups 1, 2 and 3 respectively. One third (65/197) of patients with IBS had BAM. The outcome of treatment was available in 96 patients with BAM: of the patients with ileal resection 32% responded to antidiarrhoeals, 60% to BAS. Of the unoperated Crohn's patients 55% responded to disease-specific therapy, 40% to BAS. Of the gastric surgery patients 18% responded to conventional treatment, 64% to BAS. Of the IBS patients 15% of responded to conventional therapy, 70% to BAS. CONCLUSIONS: This observational study indicates that BAM is common in patients with chronic diarrhoea, and is frequently found in IBS. The results of open treatment suggest that, where antidiarrhoeal drugs fail in such patients, BAS are often effective.


Assuntos
Ácidos e Sais Biliares/metabolismo , Doenças Funcionais do Colo/complicações , Doença de Crohn/complicações , Doença de Crohn/metabolismo , Diarreia/etiologia , Antidiarreicos/uso terapêutico , Doença Crônica , Doenças Funcionais do Colo/metabolismo , Doença de Crohn/fisiopatologia , Doença de Crohn/cirurgia , Diarreia/tratamento farmacológico , Humanos , Absorção Intestinal , Ácido Taurocólico/análogos & derivados , Ácido Taurocólico/isolamento & purificação
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