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1.
Methodol Comput Appl Probab ; 24(4): 2373-2402, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35194392

RESUMO

We study the limiting behaviour of the maximum of a bivariate (finite or infinite) moving average model, based on discrete random variables. We assume that the bivariate distribution of the iid innovations belong to the Anderson's class (Anderson, 1970). The innovations have an impact on the random variables of the INMA model by binomial thinning. We show that the limiting distribution of the bivariate maximum is also of Anderson's class, and that the components of the bivariate maximum are asymptotically independent.

2.
Int J Prosthodont ; 34(4): 365­372, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33616560

RESUMO

PURPOSE: To test whether internal accuracy affects the load-bearing capacity of 0.5-mm-thick occlusal veneers made out of milled or heat-pressed lithium disilicate (LS2). MATERIALS AND METHODS: Extracted human molars (N = 80) were divided into four groups (n = 20 each) depending on the bonding substrate (enamel [E] or dentin [D]) and the fabrication method (milling [CAD] or heat pressing [PRE]) for the occlusal LS2 veneers: (1) E-CAD, (2) D-CAD, (3) E-PRE, or (4) D-PRE. After restoration fabrication, the abutment teeth and the corresponding restorations were scanned and superimposed in order to measure the marginal and internal accuracy. After adhesive cementation, the specimens were thermomechanically aged and thereafter loaded until fracture. The load-bearing capacities (Fmax) were measured. Fmax and the marginal and internal accuracy between the groups were compared using Kruskal-Wallis test (P < .05) and pairwise group comparisons. In addition, the relationship between Fmax and the internal accuracy was analyzed using Spearman rank correlation. RESULTS: Median Fmax values (and first and third quartiles) per group were as follows: 1,495 N (Q1: 932; Q3: 2'318) for E-CAD; 1,575 N (Q1: 1,314; Q3: 1,668) for E-PRE; 1,856 N (Q1: 1,555; Q3: 2,013) for D-CAD; and 1,877 N (Q1: 1,566; Q3: 2,131) for D-PRE. No statistical difference was found between the groups (P = .0981). Overall, the internal accuracy in the areas of the cusp (P < .0007) and fossa (P < .0001) showed significant differences. While no significant differences were detected in the marginal area (P = .3518), a significant correlation with a negative linear relationship was found between the 3D internal accuracy and the Fmax values (P = .0007). CONCLUSION: An increase in the internal accuracy raised the load-bearing capacity of minimally invasive LS2 occlusal veneers. In general, the restorations bonded to dentin in the occlusal regions showed a better accuracy compared to those bonded to enamel.


Assuntos
Cerâmica , Facetas Dentárias , Idoso , Desenho Assistido por Computador , Porcelana Dentária , Análise do Estresse Dentário , Humanos , Teste de Materiais , Suporte de Carga
3.
Dent Mater ; 36(4): e109-e116, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31992483

RESUMO

OBJECTIVES: The load-bearing capacity of ultra-thin occlusal veneers made of 3D-printed zirconia were compared to the ones obtained by fabricating these reconstructions by CAD/CAM milling zirconia or heat-pressing lithium-disilicate. METHODS: On 60 extracted human molars, the occlusal enamel was removed and extended into dentin. Occlusal veneers of 0.5 mm thickness were digitally designed. The specimens were divided into 3 groups (n = 20 each) differing in the restorative material and the fabrication technique of the occlusal veneer. (1) 3DP: 3D-printed zirconia (Lithoz); (2): CAM: milled zirconia (Ceramill Zolid FX); (3) HPR: heat-pressed lithium disilicate (IPS e.max Press). After conditioning procedures, the restorations were adhesively bonded onto the conditioned tooth. Thereafter, all specimens were aged in a chewing simulator by exposure to cyclic fatigue and temperature variations. Subsequently the specimens were statically loaded and the load which was necessary to decrease the maximum load by 20% and initiate a crack (Finitial) and the load which was needed to fracture the specimen (Fmax) were measured. Differences between the groups were compared applying the Kruskal-Wallis (KW) test and the Wilcoxon-Mann-Whitney-Test (WMW: p < 0.05). RESULTS: The median Finitial values for the groups 3DP, CAM and HPR were 1'650 N, 1'250 N and 500 N. The differences between all three groups were statistically significant (KW: p < 0.0001). The median Fmax values amounted to 2'026 N for the group 3DP, 1'500 N for the group CAM and 1'555 N for the group HPR. Significant differences were found between 3DP and CAM (WMW: p = 0.0238). SIGNIFICANCE: Regarding their load-bearing capacity, 3D-printed or milled zirconia as well as heat-pressed lithium disilicate can be recommended as restorative material for ultra-thin occlusal veneers to prosthetically compensate for occlusal tooth wear. Despite statistically significant differences between the restoration materials, all load-bearing capacities exceeded the clinically expected normal bite forces.


Assuntos
Facetas Dentárias , Temperatura Alta , Cerâmica , Desenho Assistido por Computador , Porcelana Dentária , Planejamento de Prótese Dentária , Análise do Estresse Dentário , Humanos , Teste de Materiais , Dente Molar , Impressão Tridimensional , Suporte de Carga , Zircônio
4.
Osteoarthritis Cartilage ; 24(3): 480-3, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26518993

RESUMO

OBJECTIVE: To validate a new method to identify responders (relative effect per patient (REPP) >0.2) using the OMERACT-OARSI criteria as gold standard in a large multicentre sample. METHOD: The REPP ([score before - after treatment]/score before treatment) was calculated for 845 patients of a large multicenter European cohort study for THR. The patients with a REPP >0.2 were defined as responders. The responder rate was compared to the gold standard (OMERACT-OARSI criteria) using receiver operator characteristic (ROC) curve analysis for sensitivity, specificity and percentage of appropriately classified patients. RESULTS: With the criterion REPP>0.2 85.4% of the patients were classified as responders, applying the OARSI-OMERACT criteria 85.7%. The new method had 98.8% sensitivity, 94.2% specificity and 98.1% of the patients were correctly classified compared to the gold standard. CONCLUSION: The external validation showed a high sensitivity and also specificity of a new criterion to identify a responder compared to the gold standard method. It is simple and has no uncertainties due to a single classification criterion.


Assuntos
Artroplastia de Quadril/métodos , Osteoartrite do Quadril/cirurgia , Índice de Gravidade de Doença , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
6.
Clin Oral Implants Res ; 26 Suppl 11: 154-69, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25997901

RESUMO

OBJECTIVE: To compare short implants in the posterior maxilla to longer implants placed after or simultaneously with sinus floor elevation procedures. The focused question was as follows: Are short implants superior to longer implants in the augmented sinus in terms of survival and complication rates of implants and reconstructions, patient-reported outcome measures (PROMs) and costs? METHODS: A MEDLINE search (1990-2014) was performed for randomized controlled clinical studies comparing short implants (≤8 mm) to longer implants (>8 mm) in augmented sinus. The search was complimented by an additional hand search of the selected papers and reviews published between 2011 and 2014. Eligible studies were selected based on the inclusion criteria, and quality assessments were conducted. Descriptive statistics were applied for a number of outcome measures. Survival rates of dental implants were pooled simply in case of comparable studies. RESULTS: Eight randomized controlled clinical trials (RCTs) comparing short implants versus longer implants in the augmented sinus derived from an initial search count of 851 titles were selected and data extracted. In general, all studies were well conducted with a low risk of bias for the majority of the analyzed parameters. Based on the pooled analyses of longer follow-ups (5 studies, 16-18 months), the survival rate of longer implants amounted to 99.5% (95% CI: 97.6-99.98%) and for shorter implants to 99.0% (95% CI: 96.4-99.8%). For shorter follow-ups (3 studies, 8-9 months), the survival rates of longer implants are 100% (95% CI: 97.1-100%) and for shorter implants 98.2% (95% CI: 93.9-99.7%). Complications were predominantly of biological origin, mainly occurred intraoperatively as membrane perforations, and were almost three times as higher for longer implant in the augmented sinus compared to shorter implants. PROMs, morbidity, surgical time and costs were generally in favor of shorter dental implants. All studies were performed by surgeons in specialized clinical settings. CONCLUSIONS: The outcomes of the survey analyses demonstrated predictably high implant survival rates for short implants and longer implants placed in augmented sinus and their respective reconstructions. Given the higher number of biological complications, increased morbidity, costs and surgical time of longer dental implants in the augmented sinus, shorter dental implants may represent the preferred treatment alternative.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Planejamento de Prótese Dentária , Levantamento do Assoalho do Seio Maxilar , Consenso , Implantes Dentários/economia , Falha de Restauração Dentária , Humanos , Avaliação de Resultados da Assistência ao Paciente , Complicações Pós-Operatórias
7.
J Dairy Sci ; 97(4): 2193-203, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24565325

RESUMO

Suppression of cyclic activity in cattle is often desired in alpine farming and for feedlot cattle not intended for breeding. A cattle-specific anti-GnRH vaccination (Bopriva, Zoetis Australia Ltd., West Ryde, Australia) is approved for use in heifers and bulls in New Zealand, Australia, Mexico, Brazil, Argentina, Turkey, and Peru. Eleven healthy, cyclic Swiss Fleckvieh cows were included in the study and vaccinated twice with Bopriva 4wk apart. Injection site, rectal body temperature, and heart and respiratory rates were recorded before and 3d following each vaccination. Blood samples were taken weekly for progesterone and estrogen analysis and to determine GnRH antibody titer. Ovaries were examined weekly, using ultrasound to count the number of follicles and identify the presence of a corpus luteum. Thirty weeks after the first vaccination, the cows were subjected to a controlled internal drug-releasing device-based Select-Synch treatment. The GnRH antibody titers increased after the second vaccination and peaked 2wk later. Estrogen levels were not influenced by vaccination, and progesterone level decreased in 7 of 11 cows up to 3wk after the second vaccination and remained low for 10 to 15wk following the second vaccination. The number of class I follicles (diameter ≤5mm) was not influenced by vaccination, whereas the number of class II follicles (diameter 6-9mm) decreased between 7 and 16wk after the first vaccination. Class III follicles (diameter >9mm) were totally absent during this period in most cows. The median period until recurrence of class III follicles was 78d from the day of the second vaccination (95% confidence interval: 60-92d). After vaccination, all cows showed swelling and pain at the injection site, and these reactions subsided within 2wk. Body temperature and heart and respiratory rates increased after the first and second vaccinations and returned to normal values within 2d of each vaccination. The cows in our study were not observed to display estrus behavior until 30wk after the first vaccination. Therefore, a Select-Synch protocol was initiated at that time. Ten cows became pregnant after the first insemination (the remaining cow was reinseminated once until confirmed pregnancy). Bopriva induced a reliable and reversible suppression of reproductive cyclicity for more than 2mo. The best practical predictor for the length of the anestrus period was the absence of class III follicles.


Assuntos
Anestro/efeitos dos fármacos , Bovinos/fisiologia , Estrogênios/sangue , Hormônio Liberador de Gonadotropina/farmacologia , Progesterona/sangue , Vacinação/veterinária , Animais , Anticorpos/sangue , Bovinos/imunologia , Feminino , Gravidez
8.
Z Orthop Unfall ; 151(3): 239-42, 2013 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-23696160

RESUMO

BACKGROUND: The outcome of orthopaedic surgery such as total hip replacement (THR) or total knee replacement (TKR) is commonly given by the change in mean scores on patient-reported outcome measures (Prom's). This may give the impression that all enrolled patients have experienced an improvement. But the Swedish hip registry and other studies report a reduction of complaints in 80-85 % of patients ("responders"), with the remainder (approximately one in six) remaining unchanged or reporting worse complaints ("non-responders"). According to Cohen, the degree of success in the "responders" group can be subdivided into excellent, good and moderate. For a given treatment, a total of 5 different outcome groups can therefore be defined: excellent, good, moderate, unchanged and worse. Allocation to the groups is based on the "relative effect per patient" (REPP). The REPP is calculated as the base-line score minus the post-treatment score divided by the baseline score. The maximum possible REPP is 1; a REPP of 0 means no effect and a negative REPP means deterioration. Allocation to the outcome groups is as follows: excellent 0.95 to 1 REPP, good 0.5 to 0.95 REPP, moderate over 0.2 to 0.5 REPP, unchanged -0.2 to 0.2 REPP and worse below -0.2 REPP. PATIENTS AND METHODS: Our local arthroplasty register was used to evaluate the 1-year outcomes of THR and TKR patients operated between March 2003 and November 2008, using WOMAC scores and EuroQoL scores. Only patients with complete data sets and unilateral THR/TKR were included. The success rate given by the REPP method was compared with that of the "responder rate" method defined by the OMERACT-OARSI criteria. RESULTS: With the WOMAC questionnaire, outcomes were as follows (THR/TKR): excellent 29/14 %, good 51/54 %, moderate 11/13 %, unchanged at 5/12 %, worse 4/7 %. The corresponding values for the EuroQoL were (THR/TKR): excellent 16/6 %, good 41/42 %, moderate 25/28 %, unchanged 12/16 %, worse 6/8 %. For THR, success rates were 92 % using the "responder rate" method (OMERACT-OARSI criteria) and 91 % using the REPP method with the WOMAC. CONCLUSION: Calculation of the REPP and the subsequent allocation to outcome groups is simple. The distribution of outcomes depends on the intervention (THR results better than TKR) and the patient questionnaire used (better results with a condition-specific than a generic questionnaire). The proportion of "unchanged" and "moderate" outcomes was greater with the generic questionnaire than with the condition-specific questionnaire, while the proportion of "worse" outcomes was similar for the two instruments. Partitioning of the degree of success into sub-groups, based on the REPP, provides more information for both the patient and the orthopaedic surgeon.


Assuntos
Artroplastia de Quadril/estatística & dados numéricos , Artroplastia do Joelho/estatística & dados numéricos , Instabilidade Articular/epidemiologia , Instabilidade Articular/cirurgia , Avaliação de Resultados em Cuidados de Saúde/métodos , Satisfação do Paciente/estatística & dados numéricos , Inquéritos e Questionários , Idoso , Feminino , Nível de Saúde , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Prevalência , Psicometria/métodos , Psicometria/estatística & dados numéricos , Sistema de Registros , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Suíça/epidemiologia , Resultado do Tratamento
9.
Wien Klin Wochenschr ; 124(23-24): 830-3, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23184073

RESUMO

BACKGROUND: Injury from interpersonal violence is a major social and medical problem in the industrialized world. Little is known about the trends in prevalence and injury pattern or about the demographic characteristics of the patients involved. METHODS: In this retrospective analysis, we screened the database of the Emergency Department of a large university hospital for all patients who were admitted for injuries due to interpersonal violence over an 11 year period. For all patients identified, we gathered data on age, country of origin, quality of injury, and hospitalization or outpatient management. A trend analysis was performed using Kendall's tau-b correlation coefficients for regression analysis. RESULTS: The overall number of patients admitted to our Emergency Department remained stable over the study period. Non-Swiss nationals were overrepresented in comparison to the demographics of the region where the study was conducted. There was a trend toward a more severe pattern of injury, such as an increase in the number of severe head injuries. CONCLUSIONS: Although the overall number of patients remained stable over the study period, there was an alarming trend toward a more severe pattern of injury, expressed by an increase in severe head traumas.


Assuntos
Violência/tendências , Ferimentos e Lesões/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Assistência Ambulatorial/estatística & dados numéricos , Assistência Ambulatorial/tendências , Criança , Traumatismos Craniocerebrais/epidemiologia , Traumatismos Craniocerebrais/etnologia , Comparação Transcultural , Estudos Transversais , Serviço Hospitalar de Emergência/estatística & dados numéricos , Serviço Hospitalar de Emergência/tendências , Feminino , Hospitalização/estatística & dados numéricos , Hospitalização/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estatística como Assunto , Suíça , Índices de Gravidade do Trauma , Ferimentos e Lesões/etnologia , Adulto Jovem
10.
Anim Reprod Sci ; 118(2-4): 124-30, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19674853

RESUMO

Contractility of the healthy bovine myometrium depends on the reproductive state. Furthermore, contractility is influenced by localisation and the direction of smooth muscle strips. However, little is known about the contractile behaviour of the uterus when affected by endometritis. In our study, myometrial specimens from the larger horn (near the corpus and near the tip) in cows suffering from endometritis in estrus (n=8) or diestrus (n=8) were collected after slaughter. Two strips were prepared from each region corresponding to the circular and the longitudinal muscle layers, respectively. The spontaneous contractility of these strips was recorded in an organ bath. To analyse the results, the 2.5h recordings were divided into five periods of 30 min each. The variables area under curve (AUC) and maximal (A(max)) and minimal amplitude (A(min)) were calculated separately for each period, and the results were analysed using a non-parametric model regarding the influence of cycle phase (estrus vs. diestrus), region (corpus vs. tip) and muscle layer (circular vs. longitudinal). The values of both AUC and A(max) increased significantly over time. Muscle layer had a significant effect on AUC (corpus, tip) and A(max) (tip): the values of circular layers were increased compared to longitudinal layers. Dividing the data into subgroups allowed us to analyse them additionally according to muscle layer: In longitudinal layers, A(max) was increased at the corpus as compared with the tip. In this model, the factor cycle phase did not produce any significant difference in spontaneous myometrial activity. However, data of all variables showed non-significant higher values in estrus than in diestrus samples.


Assuntos
Doenças dos Bovinos/fisiopatologia , Endometrite/veterinária , Ciclo Estral/fisiologia , Músculo Liso/fisiopatologia , Contração Uterina/fisiologia , Animais , Bovinos , Diestro/fisiologia , Endometrite/patologia , Endometrite/fisiopatologia , Estro/fisiologia , Feminino , Técnicas In Vitro
11.
Z Orthop Unfall ; 145(6): 795-7, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-18072049

RESUMO

AIM: The visual analogue scale (VAS) and Likert scale (LS) are widely used but the patients might have difficulties to work with these scales and there might be errors in calculation. The visual circle scale (VCS) is a graphic construct with a simple grading to augment the understanding and ease for calculation. METHOD: This study compares the different scales in orthopaedic patients for pain assessment postoperatively. In addition, the scales were rated by the patients for simplicity, understanding and global rating. RESULTS: Included were 65 patients (40 women) with an average age of 66 years with 330 pain assessments and 65 questionnaire ratings. The average pain was LS 42.7, VAS 39.3, VCS 44. The correlation coefficients r (Spearman) between all scales were > 0.89 and the same held also for sensitivity for change. The VCS was the scale preferred by > 50 % of the orthopaedic patients to assess the pain. CONCLUSION: The VCS is able to measure pain comparably to the known scales (VAS, Likert scale). From the patients point of view it is the preferred scale to work with.


Assuntos
Procedimentos Ortopédicos , Osteoartrite/psicologia , Medição da Dor/métodos , Dor Pós-Operatória/classificação , Dor/classificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/psicologia , Medição da Dor/estatística & dados numéricos , Dor Pós-Operatória/psicologia , Psicometria/estatística & dados numéricos , Reprodutibilidade dos Testes
12.
Vet Rec ; 161(12): 414-7, 2007 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-17890770

RESUMO

A double-blinded, randomised, placebo-controlled field study of the influence of prostaglandin E2 (PGE2) on cattle at parturition was carried out. The extent of cervical opening and the intensity of labour were scored before administration of the compound and 10 minutes later; routine birth assistance was then continued by the veterinarian. Successful birth occurred more quickly in the cows treated with PGE2. The extent of cervical opening before the administration of the drug had a significant effect on the time to delivery, but the intensity of labour and a concomitant infusion of calcium did not have significant effects on this period. The less open the cervix before administration of the drug, the more the duration of parturition differed between the two groups, with the placebo group taking longer. A telephone follow-up inquiry found no significant differences between the cows postpartum; there were cases of mastitis and hypocalcaemia in both groups. The incidence of retained fetal membranes and the mortality of the calves were higher in the placebo group, but in neither case was the difference significant.


Assuntos
Colo do Útero/efeitos dos fármacos , Dinoprostona/uso terapêutico , Trabalho de Parto Induzido/veterinária , Ocitócicos/uso terapêutico , Animais , Bovinos , Dinoprostona/administração & dosagem , Método Duplo-Cego , Feminino , Injeções Intravenosas , Ocitócicos/administração & dosagem , Gravidez , Suíça , Resultado do Tratamento
13.
Surg Endosc ; 15(11): 1263-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11727130

RESUMO

BACKGROUND: There is a scarcity of data on long-term results after laparoscopic hernia repair. Herein we report on the outcome of a group of patients who were followed up for 5 years in a multicenter study on hernia repair. METHODS: A total of 100 patients with 127 hernias were randomized to undergo either transabdominal preperitoneal (TAPP) or Shouldice hernia repair. Follow-up was by clinical examination and standardized questionnaire. RESULTS: Of the 100 patients who underwent surgery, 84 were available for follow-up at 5 years. The TAPP procedure was less painful than the Shouldice repair, with fewer patients receiving narcotic analgesics. The median time to return to 100% activity was shorter in the laparoscopic group (21 days) than in the Shouldice group (40 days). Up to 60 months after the operation, the complication rate was lower in laparoscopically repaired hernias (19/66) than in the open group (25/61). There were two recurrences (3.9%) in the TAPP group and five in the Shouldice group (10.2%). CONCLUSION: The TAPP hernia repair yields comparable or better results than Shouldice herniorrhaphy in terms of postoperative pain, recovery, and recurrence rate.


Assuntos
Hérnia Inguinal/cirurgia , Laparoscopia/métodos , Idoso , Intervalos de Confiança , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Feminino , Seguimentos , Hematoma/etiologia , Humanos , Laparoscopia/efeitos adversos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Satisfação do Paciente , Recidiva , Reoperação , Resultado do Tratamento
14.
Mol Cell Biochem ; 222(1-2): 221-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11678606

RESUMO

Cr (VI) compounds are widely used industrial chemicals and are recognized human carcinogens. The mechanisms of carcinogenesis associated with these compounds remain to be investigated. The present study focused on dose-dependence of Cr (VI)-induced uptake and cellular responses. The results show that Cr (VI) is able to enter the cells (human lung epithelial cell line A549) at low concentration (< 10 microM) and that the Cr (VI) uptake appears to be a combination of saturable transport and passive diffusion. Electron spin resonance (ESR) trapping measurements showed that upon stimulation with Cr (VI), A549 cells were able to generate reactive oxygen species (ROS). The amount of ROS generated depended on the Cr (VI) concentration. ROS generation involved NADPH-dependent flavoenzymes. Cr (VI) affected the following cellular parameters in a dose-dependent manner, (a) activation of nuclear transcription factors NF-kappaB, and p53, (b) DNA damage, (c) induction of cell apoptosis, and (d) inhibition of cell proliferation. The activation of transcription factors was assessed by electrophoretic mobility shift assay and western blot analysis, DNA damage by single cell gel electrophoresis assay, cell apoptosis by DNA fragmentation assay, and cell proliferation by a non-radioactive ELISA kit. At the concentration range used in the present study, no thresholds were found in all of these cell responses to Cr (VI). The results may guide further research to better understand and evaluate the risk of Cr (VI)-induced carcinogenesis at low levels of exposure.


Assuntos
Carcinógenos/toxicidade , Cromo/toxicidade , Radical Hidroxila/metabolismo , Proteína Supressora de Tumor p53/agonistas , Antioxidantes/farmacologia , Apoptose , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Cromo/farmacocinética , Dano ao DNA , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Radical Hidroxila/agonistas , Radical Hidroxila/antagonistas & inibidores , Pulmão/citologia , Pulmão/efeitos dos fármacos
15.
Am J Gastroenterol ; 94(2): 351-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10022628

RESUMO

OBJECTIVE: In healthy subjects and patients with bleeding peptic ulcers, ranitidine and omeprazole, given parenterally, achieve high intragastric pH values on the first day of therapy. However, data on the antisecretory effect beyond the first 24 h is scanty. In addition, the superiority of either infusion or injection of omeprazole remains unproven. Thus, we have compared the antisecretory effect of high dose omeprazole and ranitidine infusion and injection over the critical first 72 h. METHODS: A total of 34 healthy volunteers were randomized into a double-blind crossover 72 h intragastric pH-metry study (data compared: median pH, percentage of time with pH >4 and pH >6). Omeprazole-infusion: initial bolus of 80 mg + 8 mg/h; omeprazole-injection: initial bolus of 80 mg + 40 mg/6 h; Ranitidine-infusion: initial bolus of 50 mg + 0.25 mg/kg/h; ranitidine-injection: 100 mg/6 h. RESULTS: Omeprazole-infusion versus ranitidine-infusion: on day 1: median pH 6.1 vs 5.1 (p = 0.01) and 95% vs 70% was pH >4 (p < 0.01); on day 2: median pH 6.2 vs 3.2 (p < 0.01); and 100% vs 38% was pH >4 (p < 0.01); on day 3: median pH 6.3 vs 2.7 (p < 0.01); 100% vs 26% was pH >4 (p < 0.01). Injections of both drugs were significantly less effective than the infusions on day 1. Thereafter, omeprazole injection was almost as effective as omeprazole infusion, whereas ranitidine injection and infusion were equally effective. CONCLUSION: Our study shows, for the first time, that omeprazole infusion was significantly superior to all other regimens by having a high median pH >6 on each day. The tolerance effect of ranitidine, however, led to a rapid loss of antisecretory activity on days 2 and 3, rendering it inappropriate for situations in which high intragastric pH-levels appear to be essential.


Assuntos
Antiulcerosos/administração & dosagem , Ácido Gástrico/metabolismo , Omeprazol/administração & dosagem , Ranitidina/administração & dosagem , Adulto , Antiulcerosos/farmacologia , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Concentração de Íons de Hidrogênio , Infusões Intravenosas , Injeções Intravenosas , Masculino , Omeprazol/farmacologia , Ranitidina/farmacologia , Fatores de Tempo
16.
Gut ; 43(5): 669-74, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9824349

RESUMO

BACKGROUND: Malignant colorectal polyps are defined as endoscopically removed polyps with cancerous tissue which has invaded the submucosa. Various histological criteria exist for managing these patients. AIMS: To determine the significance of histological findings of patients with malignant polyps. METHODS: Five pathologists reviewed the specimens of 85 patients initially diagnosed with malignant polyps. High risk malignant polyps were defined as having one of the following: incomplete polypectomy, a margin not clearly cancer-free, lymphatic or venous invasion, or grade III carcinoma. Adverse outcome was defined as residual cancer in a resection specimen and local or metastatic recurrence in the follow up period (mean 67 months). RESULTS: Malignant polyps were confirmed in 70 cases. In the 32 low risk malignant polyps, no adverse outcomes occurred; 16 (42%) of the 38 patients with high risk polyps had adverse outcomes (p<0.001). Independent adverse risk factors were incomplete polypectomy and a resected margin not clearly cancer-free; all other risk factors were only associated with adverse outcome when in combination. CONCLUSION: As no patients with low risk malignant polyps had adverse outcomes, polypectomy alone seems sufficient for these cases. In the high risk group, surgery is recommended when either of the two independent risk factors, incomplete polypectomy or a resection margin not clearly cancer-free, is present or if there is a combination of other risk factors. As lymphatic or venous invasion or grade III cancer did not have an adverse outcome when the sole risk factor, operations in such cases should be individually assessed on the basis of surgical risk.


Assuntos
Pólipos Intestinais/cirurgia , Neoplasias Retais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Transformação Celular Neoplásica , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Endoscopia/métodos , Feminino , Humanos , Pólipos Intestinais/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Poliploidia , Lesões Pré-Cancerosas/patologia , Prognóstico , Neoplasias Retais/patologia , Fatores de Risco
17.
Med Hypotheses ; 51(4): 315-20, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9824838

RESUMO

The present study was designed to investigate the hypothesis that febrile infectious childhood diseases (FICDs) are associated with a lower cancer risk in adulthood, since biographical considerations are of great importance in anthroposophic medicine. Cancer patients and control patients of 35 anthroposophic general practitioners in Switzerland were matched with respect to gender, age and physician. All patients completed a questionnaire on their FICD. We collected 424 cases; of these we could analyze 379 matched pairs. The study consistently revealed a lower cancer risk for patients with a history of FICD. The strongest associations were found between patients with non-breast cancers and rubella respectively chickenpox. A strong association was also found with the overall number of FICD both 'classical' (measles, mumps, rubella, pertussis, scarlet-fever and chickenpox) and 'other'. None of these associations was apparent for patients with breast cancer. Unexpectedly, we found that cancer was diagnosed significantly earlier in life in cancer patients with a history of FICD compared to those without FICD. Our retrospective study showed a significant association between FICD and the risk of developing cancer. The number of FICD decreased the cancer risk, in particular for non-breast cancers. The relationship with tumor site seems to be important also, but can only be addressed in a larger study.


Assuntos
Doenças Transmissíveis/epidemiologia , Febre , Neoplasias/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Estudos de Casos e Controles , Doenças Transmissíveis/complicações , Feminino , Febre/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Razão de Chances , Estudos Retrospectivos , Fatores de Risco , Inquéritos e Questionários , Suíça/epidemiologia
18.
Aliment Pharmacol Ther ; 12(4): 337-42, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9690722

RESUMO

BACKGROUND: Symptoms of functional dyspepsia are common and patients often self-medicate with antacids, or with low-dose H2-antagonists which are available as over-the-counter medications. To date, there has been limited information available comparing the effects on intragastric acidity of these two types of over-the-counter medication. Therefore we studied the effect of the antacid Rennie and two H2-antagonists on the intragastric pH of fasting volunteers. METHODS: Sixteen healthy, fasting volunteers were randomized into a double-blind, placebo-controlled, four-way crossover study comparing Rennie (calcium-magnesium carbonate) 1360 mg, ranitidine 75 mg, famotidine 10 mg and placebo. Their effect on gastric pH was monitored by a 4-h gastric pH-metry. The primary efficacy parameter was the time lag before an intragastric pH > 3.0 was reached after drug administration. RESULTS: The median time lag before pH > 3.0 was reached after drug administration was 5.8 min for Rennie, 64.9 min for ranitidine, 70.1 min for famotidine and 240.0 min for placebo. The percentage of time with values of pH > 3.0 was 10.4% for Rennie, 61.4% for ranitidine, 56.6% for famotidine and 1.4% for placebo. CONCLUSION: The onset of action in fasting volunteers was significantly faster with the antacid than with the two H2-antagonists. The duration of action was significantly longer with an H2-antagonist than with the antacid. This suggests that the two products should be used for different indications: antacids are superior for rapid pain relief, whereas H2-antagonists might be better for symptom prophylaxis--for example for nocturnal dyspepsia.


Assuntos
Antiácidos/farmacologia , Carbonato de Cálcio/farmacologia , Carbonatos/farmacologia , Famotidina/farmacologia , Ácido Gástrico/metabolismo , Antagonistas dos Receptores H2 da Histamina/farmacologia , Magnésio/farmacologia , Ranitidina/farmacologia , Administração Oral , Adulto , Antiácidos/administração & dosagem , Carbonato de Cálcio/administração & dosagem , Carbonatos/administração & dosagem , Método Duplo-Cego , Dispepsia/prevenção & controle , Famotidina/administração & dosagem , Feminino , Antagonistas dos Receptores H2 da Histamina/administração & dosagem , Humanos , Magnésio/administração & dosagem , Masculino , Dor/tratamento farmacológico , Ranitidina/administração & dosagem , Fatores de Tempo
19.
Surg Endosc ; 10(8): 845-7, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8694951

RESUMO

BACKGROUND: In February 1993 a prospective randomized multicenter trial was initiated to compare laparoscopic transabdominal preperitoneal hernioplasty to Shouldice herniorrhaphy as performed by surgeons of nonspecialized clinics. METHODS: Until January 1994, 87 patients with 108 hernias took part in the trial (43 Shouldice and 44 laparoscopic repairs). RESULTS: The laparoscopic procedure took significantly longer than did the open operation but caused less pain as measured by pain analogue score and consumption of paracetamol and narcotics. The postoperative complication rate was 26% in the open and 16% in the laparoscopic group. The patients in the laparoscopic group were discharged earlier and their convalescence was shorter than after open hernia repair. There has been one early recurrence in the laparoscopic and two in the open group to date with a mean follow-up of 201 days. CONCLUSIONS: Laparoscopic hernia repair causes less pain than the conventional operation and enables the patient to return to full work and usual activities earlier. The recurrence rate will not be known for 5 years.


Assuntos
Hérnia Inguinal/cirurgia , Laparoscopia/métodos , Abdome , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Peritônio , Complicações Pós-Operatórias , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento
20.
J Res Natl Inst Stand Technol ; 99(4): 539-542, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-37405288

RESUMO

It is known that the number of exceedances of normal sequences is asymptotically a Poisson random variable, under certain restrictions. We analyze the rate of convergence to the Poisson limit and extend the result known in the stationary case to nonstationary normal sequences by using the Stein-Chen method. In addition, we consider the cases of exceedances of a constant level as well as of a particular nonconstant level.

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