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OBJECTIVE: Virtual reality (VR) objects of fetal ultrasound volumes have been proposed for teaching and learning diagnostic ultrasound. The aim of this study was to determine if VR objects improve learning efficiency and retention of diagnostic ability in fetal ultrasound. METHODS: Medical students and junior doctors were taught normal and abnormal sonographic fetal brain anatomy using conventional means (video lectures and review articles; control group) or additionally with selected VR objects from a novel fetal brain atlas (Pocket Brain, http://pb.fetal.ch; study group). Knowledge, speed of recognition and retention of diagnostic ability were tested in multiple-choice questionnaires 1 and 4 months after teaching, and the results were compared between those taught using conventional means only and those taught using VR objects. RESULTS: Participants taught using VR objects answered significantly more questions correctly and solved the tests quicker than those taught using conventional methods only, both 1 and 4 months after teaching. CONCLUSION: The use of VR objects in teaching fetal ultrasound significantly improves learning efficiency and knowledge retention. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
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Anatomia/educação , Encéfalo/diagnóstico por imagem , Ultrassonografia Pré-Natal , Realidade Virtual , Encéfalo/anatomia & histologia , Encéfalo/embriologia , Estudos de Casos e Controles , Feminino , Humanos , Gravidez , Avaliação de Programas e Projetos de Saúde , Distribuição Aleatória , Treinamento por SimulaçãoRESUMO
OBJECTIVE: Acute out-of-hours (OOH) healthcare is challenged by potentially long waiting time for callers in acute need of medical aid. OOH callers must usually wait in line, even when contacting for highly urgent or life-threatening conditions. We tested an emergency access button (EAB), which allowed OOH callers to bypass the waiting line if they perceived their health problem as severe. We aimed to investigate EAB use and patient characteristics associated with this use. DESIGN: Comparative intervention study. SETTING: OOH services in two major Danish healthcare regions. INTERVENTION: Giving callers the option to bypass the telephone waiting line by introducing an EAB. PARTICIPANTS: OOH service callers contacting during end of October to mid-December 2017. MAIN OUTCOME MEASURES: Proportions of EAB use, waiting time and background information on participants in two settings differing on organisation structure, waiting time and triage personnel. RESULTS: In total, 97,791 out of 158,784 callers (61.6%) chose to participate. The EAB was used 2905 times out of 97,791 (2.97%, 95%CI 2.86; 3.08). Patient characteristics associated with increased EAB use were male gender, higher age, low education, being retired, and increasing announced estimated waiting time. In one region, immigrants used the EAB more often than native Danish callers. CONCLUSION: Only about 3% of all callers chose to bypass the waiting line in the OOH service when given the option. This study suggests that the EAB could serve as a new and simple tool to reduce the waiting time for severely ill patients in an OOH service telephone triage setting. Key Points Acute out-of-hours healthcare is challenged by overcrowding and increasing demand for services. This study shows that only approximately 3% of callers chose to bypass the telephone waiting queue when given the opportunity through an emergency access button. An emergency access button may serve as a new tool to help reduce the triage waiting time for severely ill patients in out-of-hours medical facilities.
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Plantão Médico , Comportamento de Escolha , Emergências , Acessibilidade aos Serviços de Saúde , Autoavaliação (Psicologia) , Telefone , Listas de Espera , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Atenção à Saúde , Dinamarca , Feminino , Serviços de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Atenção Primária à Saúde , Índice de Gravidade de Doença , Fatores Socioeconômicos , Triagem , Adulto JovemRESUMO
Objectives: Out-of-hours (OOH) services provide access to healthcare outside normal office hours, but the waiting time can sometimes be long. All callers must wait in the telephone queue, even if the health problem is urgent or life-threatening. We tested an emergency access button (EAB), which allowed callers with perceived severe health problems to bypass the queue. We aimed to investigate the severity of the health problems and the relevance of EAB use (assessed by triage professionals). Additionally, we aimed to calculate the number of suspected acute myocardial infarctions (AMI) and ambulance dispatches. Design: Descriptive study of a randomized intervention. Setting: OOH services in two major Danish healthcare regions. Subjects: 217,510 callers participated; 146,355 were randomized to intervention, and 6554 of 6631 (98.8%) questionnaires were completed by OOH triage professionals. Intervention: An EAB allowing randomly selected callers to bypass the telephone queue. Main outcome measures: Severity of contact and relevance of EAB use. Number of suspected AMIs and ambulance dispatches. Results: In both settings, contacts with EAB use concerned significantly more severe health problems than contacts without EAB use (p < 0.001). Triage professionals rated EAB use as "not relevant" in 23% of cases. Significantly more EAB users (10.4%) than EAB non-users (3.3% with EAB option and 1.7% without EAB option, p < 0.001) had a suspected AMI. Conclusions: We found higher proportions of severe health problems, suspected AMIs, and ambulance dispatches among EAB users. Only 23% of EAB use was rated "not relevant". This suggests that the EAB is used as intended. Key points Out-of-hours healthcare is challenged by increasing demand and long triage waiting times. An emergency access button may allow severely ill callers to jump the queue. Callers who bypassed the queue were more severely ill than callers who did not bypass the queue. Only 23% of bypassers presented "not relevant" health problems according to the triage staff.Trial registration: Identifier NCT02572115 registered at Clinicaltrials.gov on 5 October 2015.
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Plantão Médico , Emergências , Serviço Hospitalar de Emergência , Acessibilidade aos Serviços de Saúde , Índice de Gravidade de Doença , Telefone , Triagem , Adolescente , Adulto , Idoso , Ambulâncias , Criança , Dinamarca , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio , Aceitação pelo Paciente de Cuidados de Saúde , Fatores de TempoRESUMO
The OPERA experiment was designed to study ν_{µ}âν_{τ} oscillations in the appearance mode in the CERN to Gran Sasso Neutrino beam (CNGS). In this Letter, we report the final analysis of the full data sample collected between 2008 and 2012, corresponding to 17.97×10^{19} protons on target. Selection criteria looser than in previous analyses have produced ten ν_{τ} candidate events, thus reducing the statistical uncertainty in the measurement of the oscillation parameters and of ν_{τ} properties. A multivariate approach for event identification has been applied to the candidate events and the discovery of ν_{τ} appearance is confirmed with an improved significance level of 6.1σ. |Δm_{32}^{2}| has been measured, in appearance mode, with an accuracy of 20%. The measurement of the ν_{τ} charged-current cross section, for the first time with a negligible contamination from ν[over ¯]_{τ}, and the first direct evidence for the ν_{τ} lepton number are also reported.
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BACKGROUND: Out-of-hours (OOH) health care for acute medical problems is often challenged by long waiting time for callers in need of advice and triage. Allowing patients to bypass the OOH telephone waiting line may increase patient satisfaction and provide them with a feeling of safety. We aimed to develop an "emergency access button" enabling patients to bypass the normal telephone waiting line in out-of-hours primary care (OOH-PC) if they perceive their condition to be critical and to evaluate the effect of introducing the button in terms of patient satisfaction and their feeling of safety. METHODS: All patients calling the OOH-PC in two different Danish health care regions during three months will be included in this randomized controlled trial. Data will be collected through two questionnaires developed for this study: a pop-up questionnaire on the relevance of bypassing the normal waiting line to be completed by triage professionals after patient contact and a paper/electronic questionnaire on perceived safety and satisfaction with the emergency access button to be completed by the callers. These questionnaires were developed and validated using external and internal expert feedback, focus group interviews and a two-week field test. The study will be conducted over three months with an estimated user-rate of the emergency access button of 3%. DISCUSSION: We have developed an emergency access button and we now want to investigate whether this new option will influence upon the level of satisfaction and the feeling of safety in the calling patients. Additionally, the study will reveal the assessed relevance of the decision to bypass the line by triage professionals. TRIAL REGISTRATION: Registered as NCT02572115 at Clinicaltrials.gov on October 5th 2015.
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Plantão Médico , Emergências , Acessibilidade aos Serviços de Saúde , Atenção Primária à Saúde , Dinamarca , Feminino , Humanos , Masculino , Satisfação do Paciente , Inquéritos e Questionários , Telefone , Triagem/métodosRESUMO
The OPERA experiment was designed to search for ν_{µ}âν_{τ} oscillations in appearance mode, i.e., by detecting the τ leptons produced in charged current ν_{τ} interactions. The experiment took data from 2008 to 2012 in the CERN Neutrinos to Gran Sasso beam. The observation of the ν_{µ}âν_{τ} appearance, achieved with four candidate events in a subsample of the data, was previously reported. In this Letter, a fifth ν_{τ} candidate event, found in an enlarged data sample, is described. Together with a further reduction of the expected background, the candidate events detected so far allow us to assess the discovery of ν_{µ}âν_{τ} oscillations in appearance mode with a significance larger than 5σ.
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The OPERA experiment was designed to discover the vτ appearance in a vµ beam, due to neutrino oscillations. The detector, located in the underground Gran Sasso Laboratory, consisted of a nuclear photographic emulsion/lead target with a mass of about 1.25 kt, complemented by electronic detectors. It was exposed from 2008 to 2012 to the CNGS beam: an almost pure vµ beam with a baseline of 730 km, collecting a total of 1.8·1020 protons on target. The OPERA Collaboration eventually assessed the discovery of vµâvτ oscillations with a statistical significance of 6.1 σ by observing ten vτ CC interaction candidates. These events have been published on the Open Data Portal at CERN. This paper provides a detailed description of the vτ data sample to make it usable by the whole community.
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In an attempt to modulate the recognition processes that occur on lymphocyte membranes in mixed lymphocyte culture, responding cortisone resistant thymocytes or stimulating spleen cells (treated with mitomycin C) were pretreated with native concanavalin A (N-Con A) or succinyl-Con A (S-Con A). Highly significant cell proliferation was observed in syngeneic combinations when either the responding cells or the stimulating cells were so treated with Con A, although Con A pretreatment alone was never mitogenic. In allogeneic combinations the proliferative response with Con A pretreatment of either partner on day 3 was five to seven times higher than in the normal mixed lymphocyte reactions. The triggering of proliferation was dependent on two factors: (a) The presence of spleen cells as the stimulating cells (thymocytes were much less effective). (b) The binding of Con A molecules to either one of the partners, the effect being abrogated by the specific inhibitor of Con A, alpha-mannopyranoside. The optimal concentration of S-Con A was about twice that of N-Con A. Even more striking was the observation that cultures in which either one of the partners was pretreated with Con A in allogeneic combinations showed a strong suppression (60-80% inhibition) in the subsequent generation of the cytotoxic lymphocytes (CL). The Con A concentration required to trigger a proliferative response corresponded to that for suppressing the generation of CL. Con A pretreatment did not result in a cytotoxic activity toward syngeneic tumor cells.
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Concanavalina A/farmacologia , Baço/imunologia , Linfócitos T/efeitos dos fármacos , Animais , Divisão Celular/efeitos dos fármacos , Testes Imunológicos de Citotoxicidade , Relação Dose-Resposta a Droga , Ativação Linfocitária/efeitos dos fármacos , Teste de Cultura Mista de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos , Linfócitos T/imunologiaRESUMO
The proliferative response of mouse lymphocytes to syngeneic cellular stimulation upon membrane modification with lectins was studied. Brief pretreatment of stimulator cells (mitomycin-C-treated spleen cells) followed by mixed culture with syngeneic cortisone-resistant thymocytes resulted in a significant proliferative response in the thymocytes. This effect was not due to a soluble mediator and was similar to the mitogenic response after Con A-induced membrane modification reported previously. Because of its general characteristics, we refer to this response as cell-mediated mitogenic response (CMMR). Cell contact between stimulator and responder cells was necessary but not sufficient for the induction of the response. The lectins that generated CMMR were T-cell mitogens. CMMR was generated in all the syngeneic combinations tested and even in allogeneic combinations. No detectable cytotoxic activity towards syngeneic targets cells was produced after CMMR. Moreover, CMMR in allogeneic combinations led to the suppression of the generation of specific cytotoxic lymphocytes. Population analysis with antibodies against T or B cells, nylon wool fractionation of stimulator cells, and tests with peritoneal macrophages and with spleen cells from athymic mice revealed that CMMR depends predominantly on the interaction between responder T cells and stimulator Ig-positive lymphocytes.
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Aglutininas , Lectinas , Ativação Linfocitária , Linfócitos T/imunologia , Aglutinação , Animais , Linfócitos B/imunologia , Separação Celular , Células Cultivadas , Concanavalina A , Testes Imunológicos de Citotoxicidade , DNA/biossíntese , Macrófagos/imunologia , CamundongosRESUMO
Mechano-electrical transduction (MET) in the stereocilia of outer hair cells (OHCs) was studied in newborn Wistar rats using scanning electron microscopy to investigate the stereociliar cross-links, Nomarski laser differential interferometry to investigate stereociliar stiffness and by testing the functionality of the MET channels by recording the entry of fluorescent dye, FM1-43, into stereocilia. Preparations were taken from rats on their day of birth (P0) or 1-4 days later (P1-P4). Hair bundles developed from the base to the apex and from the inner to outer OHC rows. MET channel responses were detected in apical coil OHCs on P1. To study the possible recovery of MET after disrupting the cross-links, the same investigations were performed after the application of Ca(2+) chelator 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) and allowing the treated samples to recover in culture medium for 0-20 h. We found that the structure and function were abolished by BAPTA. In P0-P1 samples, structural recovery was complete and the open probability of MET channels reached control values. In P3-P4 samples, complete recovery only occurred in OHCs of the outermost row. Although our results demonstrate an enormous recovery potential of OHCs in the postnatal period, the structural component restricts the potential for therapy in patients.
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Quelantes/farmacologia , Ácido Egtázico/análogos & derivados , Células Ciliadas Auditivas Internas/fisiologia , Transdução de Sinais/fisiologia , Animais , Animais Recém-Nascidos , Ácido Egtázico/farmacologia , Células Ciliadas Auditivas Internas/ultraestrutura , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Microscopia de Interferência , Compostos de Piridínio/química , Compostos de Amônio Quaternário/química , Ratos , Ratos WistarRESUMO
AIM: To assess the efficacy of removing Activ GP or GuttaFlow from canals using NiTi instruments. METHODOLOGY: Root canals in 55 extracted pre-molars were prepared to apical size 40, 0.04 taper. The teeth were imaged with micro-CT, and 30 teeth selected that had consistent apical size and taper of the shaped canals. They were randomly assigned to root filling with either the glass-ionomer-based ActivGP system (n = 15) or the polyvinylsiloxane-based GuttaFlow system (n = 15). After 2 weeks, canals were retreated stepwise with size 40-50 EndoSequence 0.04 taper instruments. Micro-CT scans (8 mum) were taken after use of each instrument to detect root filling residue in the coronal, middle and apical segment, and the retreatment time recorded. Residue, expressed as percentage of canal surface area, was compared between groups with t-tests, and within groups with repeated measures anova and Bonferroni-adjusted pairwise comparisons. Retreatment time was analysed with one-way anova. RESULTS: The percentage of sealer residue-coated canal surface was consistently highest (P < 0.001) in the apical third of canals, and it did not differ significantly between the two root filling groups. Stepwise enlargement from size 40 to 50 significantly decreased the amount of sealer residue in both groups (P < 0.001). Retreatment time did not differ significantly between groups. CONCLUSIONS: Both root fillings with ActivGP and GuttaFlow were removed with nickel-titanium rotary instruments. Enlargement of canals up to two sizes beyond the pre-retreatment size was necessary to minimize the amount of sealer remaining.
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Cavidade Pulpar/diagnóstico por imagem , Preparo de Canal Radicular/instrumentação , Camada de Esfregaço , Resinas Acrílicas , Análise de Variância , Dente Pré-Molar , Ligas Dentárias , Instrumentos Odontológicos , Dimetilpolisiloxanos , Combinação de Medicamentos , Cimentos de Ionômeros de Vidro , Guta-Percha , Humanos , Níquel , Polivinil , Retratamento , Materiais Restauradores do Canal Radicular , Preparo de Canal Radicular/métodos , Siloxanas , Estatísticas não Paramétricas , Titânio , Microtomografia por Raio-XRESUMO
OBJECTIVE: To determine the effectiveness of 'accelerated' compared to 'traditional' post-operative load bearing rehabilitation protocols following matrix-induced autologous chondrocyte implantation (MACI). METHOD: A randomized controlled study design was used to investigate clinical, biomechanical and radiographic assessment at 3 months post-surgery in 62 patients following MACI to the medial or lateral femoral condyle. Both rehabilitation interventions sought to protect the implant for an initial period, then incrementally increase load bearing. Under the 'accelerated' protocol, patients reached full weight bearing at 8 weeks post-surgery, compared to 11 weeks for the 'traditional' group. RESULTS: Patients in the 'accelerated' group achieved greater 6 min walk distances and daily activity levels as measured by accelerometry (P<0.05) compared to the 'traditional' group. Furthermore, the 'accelerated' group reported significantly better improvement in knee pain at 12 weeks as indicated by the Knee Injury and Osteoarthritis Outcome Score (P<0.05), and regardless of the rehabilitation protocol employed, no patient suffered any adverse effect to the implant as assessed by magnetic resonance imaging at 3 months. Comparison of each rehabilitation group with an unaffected control group revealed a significant difference in peak knee adduction and flexion moments for the traditional group (P<0.05). However, there was no difference for accelerated patients (P>0.05), which may demonstrate a faster return to knee loading patterns typically observed in unaffected subjects. CONCLUSION: The 'accelerated' load bearing approach that reduced the length of time spent ambulating on crutches resulted in reduced knee pain, improved function, no graft complications and may speed up the recovery of normal gait function. Patient follow-up to at least 24 months would be required to observe longer-term graft outcomes.
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Cartilagem Articular/transplante , Condrócitos/transplante , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/cirurgia , Transplante Autólogo/métodos , Adolescente , Adulto , Cartilagem Articular/cirurgia , Avaliação da Deficiência , Feminino , Marcha/fisiologia , Humanos , Articulação do Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/fisiopatologia , Osteoartrite do Joelho/reabilitação , Cuidados Pós-Operatórios/reabilitação , Amplitude de Movimento Articular/fisiologia , Índice de Gravidade de Doença , Estatística como Assunto , Transplante Autólogo/reabilitação , Suporte de Carga/fisiologiaRESUMO
AIM: To investigate dye permeability of root dentine according to patients' age, root section and dye penetration time. METHODOLOGY: A total of 96 extracted human single-rooted teeth, assigned to four age groups (<30, 30-45, 45-60 and >60 years) were separated at the cemento-enamel junction and root canals were enlarged. The root surfaces were coated with cyanocrylate to prevent external dye penetration and centrifuged in distilled water to eliminate air. For dye penetration the root canals were filled with methylene blue 5%. After 1, 30 and 60 days eight roots per age group were cross-sectioned in 1 mm slices. Dye penetrated areas and the complete dentine areas were digitized and measured. Differences between groups were judged with anova and LSD, P < 0.05 or P < 0.01. RESULTS: The root section, the patients' age and the penetration time influenced significantly the penetrated areas (P < 0.05). After 1 and 30 days significant differences could be found only in the apical root sections between all age groups (P < 0.05). Dye penetration areas systematically decreased with increasing age and also from coronal to apical (P < 0.01). CONCLUSIONS: Age influenced dye penetration significantly. Dye penetration also depended on the location (coronal, middle and apical) within the root canal. These findings indicate that there may be a correlation between the tooth age and permeability of root dentine, which may influence the distribution and effectiveness of drugs used for root canal disinfection.
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Envelhecimento/patologia , Corantes , Cavidade Pulpar/patologia , Permeabilidade da Dentina , Dentina/patologia , Raiz Dentária/patologia , Adulto , Envelhecimento/metabolismo , Calcinose/metabolismo , Calcinose/patologia , Cavidade Pulpar/metabolismo , Dentina/metabolismo , Permeabilidade da Dentina/fisiologia , Dentina Secundária/metabolismo , Dentina Secundária/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Azul de Metileno , Pessoa de Meia-Idade , Fotografia Dentária , Preparo de Canal Radicular/métodos , Fatores de Tempo , Ápice Dentário/metabolismo , Ápice Dentário/patologia , Raiz Dentária/metabolismoRESUMO
8-epi-prostaglandin F2 alpha (8-epi-PGF2 alpha) and related compounds are novel prostanoid produced by a noncyclooxygenase mechanism involving lipid peroxidation. Renal ischemia-reperfusion injury increased urinary excretion of these compounds by 300% over baseline level. Intrarenal arterial infusion at 0.5, 1, and 2 micrograms/kg per min induced dose-dependent reductions in glomerular filtration rate (GFR) and renal plasma flow, with renal function ceasing at the highest dose. Micropuncture measurements (0.5 microgram/kg per min) revealed a predominant increase in afferent resistance, resulting in a decrease in transcapillary hydraulic pressure difference, and leading to reductions in single nephron GFR and plasma flow. These changes were completely abolished or reversed by a TxA2 receptor antagonist, SQ 29,548. Competitive radioligand binding studies demonstrated that 8-epi-PGF2 alpha is a potent competitor for [3H]SQ 29,548 binding to rat renal arterial smooth muscle cells (RASM) in culture. Furthermore, addition of 8-epi-PGF2 alpha to RASM or isolated glomeruli was not associated with stimulation of arachidonate cyclooxygenase products. Therefore, 8-epi-PGF2 alpha is a potent preglomerular vasoconstrictor acting principally through TxA2 receptor activation. These findings may explain, in part, the beneficial effects of antioxidant therapy and TxA2 antagonism observed in numerous models of renal injury induced by lipid peroxidation.
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Dinoprosta/análogos & derivados , Dinoprosta/farmacologia , Glomérulos Renais/efeitos dos fármacos , Receptores de Prostaglandina/fisiologia , Tromboxano A2/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes , Ácidos Graxos Insaturados , Radicais Livres , Taxa de Filtração Glomerular/efeitos dos fármacos , Hematócrito , Hidrazinas/metabolismo , Glomérulos Renais/metabolismo , Masculino , Ratos , Ratos Endogâmicos , Receptores de Prostaglandina/efeitos dos fármacos , Receptores de Tromboxanos , Circulação Renal/efeitos dos fármacosRESUMO
Thirty-four neonatal beagles were inoculated with cells obtained originally from 2 adult beagles, 1 with lymphocytic leukemia, the other with generalized malignant lymphoma. Most of the puppies were irradiated before inoculation; a few were inoculated in utero and were not irradiated. Of the 11 puppies inoculated with buffy coat cells of the blood from the leukemic donor, 2 developed leukemia. Of the 23 pups inoculated with cells of lymph nodes from the spontaneous lymphoma or positive passages, 13 developed lymphoma. Time of measurable onset of leukemia or lymphoma in the recipients varied from 12-60 days after inoculation. One passage was achieved with the leukemia and three serial passages with the lymphoma. A female karyotype was obtained from a neoplastic lymph node in a male recipient of the lymphoma. Since the donor was female, this suggests that the passages of the lymphoma were transplants.
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Leucemia Linfoide/patologia , Linfoma/patologia , Animais , Animais Recém-Nascidos , Cromossomos de Mamíferos , Cães , Feminino , Cariotipagem , Leucemia Linfoide/genética , Metástase Linfática , Linfoma/genética , Masculino , Transplante de Neoplasias , Fatores de TempoRESUMO
Prolyl 4-hydroxylase (EC 1.14.11.2) is a key enzyme in collagen biosynthesis, its active form is a tetramer (alpha 2 beta 2). In L-929 fibroblasts in the log phase of culture there is a low level of active enzyme. When the cell culture reaches confluency, prolyl hydroxylase activity in cells increases by a process that requires de novo RNA and protein synthesis. The same result may be achieved by crowding the cells (replating log phase cells at the density of stationary phase cells). In the work reported here we further examined induction of the enzyme. RNA synthesis necessary for enzyme induction is complete 6 h after "crowding" while protein synthesis requires 12 h. Thymidine (0.2-0.5 mM) added to log phase cells will also cause enzyme induction to the level found in "crowded" or resting cells. We also looked at the decay of the enzyme activity after subculture. This occurs rapidly (enzyme half-life is 1-2 h) and is concurrent with the re-entry of resting cells into cell cycle; however, thymidine added at the time of subculture to block DNA synthesis does not prevent the loss of prolyl hydroxylase activity. These results suggest that when cells are not engaged in propagation, they begin to synthesize luxury proteins such as prolyl hydroxylase. However, the loss of prolyl hydroxylase during subculture is probably not a direct consequence of DNA synthesis.
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Células L/enzimologia , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Animais , Contagem de Células , Divisão Celular , DNA/biossíntese , Indução Enzimática/efeitos dos fármacos , Cinética , Células L/citologia , Camundongos , RNA/biossíntese , Timidina/farmacologiaRESUMO
We examined T-cells, B-cells, and natural killer cells of four normal individuals for surface-bound fibronectin (FN) using fluorescence-activated cell sorter analysis and double fluorescence labeling with monoclonal antibodies. While Leu 12 (CD 19)-positive B-cells stained also uniformly with anti-FN antibody, neither OKT 3 (CD 3)-positive T-cells nor Leu 11 (CD 16)-positive natural killer cells could be labeled with anti-FN. Although an anti-FN receptor antibody was not available, these data strongly suggest a distinct pattern of FN-binding by human lymphocytes.
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Linfócitos B/análise , Fibronectinas/análise , Células Matadoras Naturais/análise , Linfócitos T/análise , Anticorpos Monoclonais/imunologia , Separação Celular , Fibronectinas/imunologia , Citometria de Fluxo , Humanos , Linfócitos T/classificaçãoRESUMO
Current techniques for endoscopic carpal tunnel release use an infraretinacular approach, inserting the endoscope deep to the flexor retinaculum. We present a supraretinacular endoscopic carpal tunnel release technique in which a dissecting endoscope is inserted superficial to the flexor retinaculum, which improves vision and the ability to dissect and manipulate the median nerve and tendons during surgery. The motor branch of the median nerve and connections between the median and ulnar nerve can be identified and dissected. Because the endoscope is inserted superficial to the flexor retinaculum, the median nerve is not compressed before division of the retinaculum and, as a result, we have observed no cases of the transient median nerve deficits that have been reported using infraretinacular endoscopic techniques.
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Síndrome do Túnel Carpal/cirurgia , Ligamentos/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Dissecação , Endoscopia , Feminino , Humanos , Masculino , Nervo Mediano/cirurgia , Pessoa de Meia-Idade , Estudos Prospectivos , Nervo Ulnar/cirurgiaRESUMO
We have analyzed the polarized cell surface expression of the G protein-coupled vasopressin V2 receptor (V2 receptor) in Madin-Darby canine kidney (MDCK) epithelial cells by both conventional cell surface biotinylation assays and laser scanning microscopy of green fluorescent protein (GFP)-tagged receptors. Cell surface biotinylation assays with stably transfected filter-grown cells expressing alkaline phosphatase (PhoA)-tagged receptors demonstrated that the V2 receptor is located predominantly basolaterally at steady state, while minor amounts are expressed apically. Laser scanning microscopy of filter- and glass-grown MDCK cells stably transfected with a GFP-tagged V2 receptor confirmed that the receptor is expressed mainly basolaterally; within the basolateral compartment, however, the receptor was confined to the lateral subdomain. The results obtained with the GFP-tagged receptor are thus consistent with and refine those from the biotinylation assay, which does not discriminate lateral from basal membrane regions. Our data indicate that the GFP methodology may effectively supplement cell surface biotinylation assays in future studies of polarized receptor transport. We finally show that microinjection of a plasmid encoding the GFP-tagged V2 receptor into the nucleus of MDCK cells led to the same results as experiments with stably transfected cells. However, since there was no need for selecting stably transfected cell lines, the experiments were complete within hours. The microinjection technique thus constitutes a powerful single cell technique to study the intracellular transport of G protein-coupled receptors. The methodology may be applicable to any cell type, even to tissue-derived, primary cultured cells; coinjection of transport-regulating compounds should also be possible.
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Receptores de Vasopressinas/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Transporte Biológico , Linhagem Celular , Membrana Celular/metabolismo , DNA Complementar , Cães , Proteínas de Fluorescência Verde , Rim/metabolismo , Proteínas Luminescentes/metabolismo , Microinjeções , Plasmídeos , Proteínas Recombinantes de Fusão/metabolismo , TransfecçãoRESUMO
Previous studies have suggested that levels of cerebrospinal fluid (CSF) gamma-aminobutyric acid (GABA) may be decreased in children with febrile seizures. We used gas chromatography and mass spectrometry to measure CSF GABA levels in 14 children with febrile seizures. The results were compared with the GABA levels in six children with first-time afebrile seizures, three with recurrent febrile seizures, and 13 controls (febrile children undergoing lumbar puncture to rule out meningitis). Children with central nervous system infections or known neurologic disease were excluded. The CSF GABA levels in children with febrile seizures were not significantly different from those in controls and children with afebrile or recurrent febrile seizures. In the control group, CSF GABA levels correlated with increasing age. There was no correlation with severity of febrile response in any group. The results indicated that the CSF GABA level may not be abnormal in patients with first-time febrile convulsions.