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1.
Virus Evol ; 7(2): veab058, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34532061

RESUMO

Human polyomaviruses are widespread in humans and can cause severe disease in immunocompromised individuals. To identify human genetic determinants of the humoral immune response against polyomaviruses, we performed genome-wide association studies and meta-analyses of qualitative and quantitative immunoglobulin G responses against BK polyomavirus (BKPyV), JC polyomavirus (JCPyV), Merkel cellpolyomavirus (MCPyV), WU polyomavirus (WUPyV), and human polyomavirus 6 (HPyV6) in 15,660 individuals of European ancestry from three independent studies. We observed significant associations for all tested viruses: JCPyV, HPyV6, and MCPyV associated with human leukocyte antigen class II variation, BKPyV and JCPyV with variants in FUT2, responsible for secretor status, MCPyV with variants in STING1, involved in interferon induction, and WUPyV with a functional variant in MUC1, previously associated with risk for gastric cancer. These results provide insights into the genetic control of a family of very prevalent human viruses, highlighting genes and pathways that play a modulating role in human humoral immunity.

2.
Nutr Rev ; 79(5): 585-598, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32918470

RESUMO

INTRODUCTION: The omega-3 long-chain polyunsaturated fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are important for brain development and cognitive performance. Because they are semi-essential fatty acids, they must be obtained from food. However, the dietary reference intakes of DHA and EPA have not yet been established. In women, a low DHA and/or EPA serum level during pregnancy or breastfeeding might negatively affect their children. For this study, we conducted a systematic review and meta-analysis of randomized control trials on the association between the consumption of fish oil supplements in pregnant and/or breastfeeding women and the cognitive performance of their children. METHODS: The PubMed, Embase, and Central literature databases were systematically searched. We included and extracted relevant studies in duplicate and assessed study quality. Cognitive outcomes were grouped according to published criteria and according to time elapsed after the intervention. We performed fixed-effects meta-analyses for each cognitive outcome and for birth weight. We assessed potential confounding with meta-regressions and sensitivity analyses. RESULTS: A total of 11 trials were included. No significant association was found between DHA/EPA supplementation and any of the assessed cognitive parameters or birth weight. DISCUSSION: Our results confirm previous reviews on the studied topic. Reasons for inconclusive results may be small sample sizes for each assessed category, questionable quality of included studies, and the difficulty of reliably measuring cognitive performance in small children. Blood levels of omega-3 long-chain polyunsaturated fatty acids were mostly not comparable. Furthermore, the influence of genetic and environmental factors could not be assessed. Studies in this field should address such shortcomings.


Assuntos
Cognição/efeitos dos fármacos , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Criança , Pré-Escolar , Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Feminino , Humanos , Lactente , Gravidez
3.
Eur J Neurol ; 28(2): 579-586, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33065762

RESUMO

BACKGROUND AND PURPOSE: Infections with human herpesvirus 6A (HHV-6A) and Epstein-Barr virus (EBV) have been linked to multiple sclerosis (MS) development. For EBV, late infection has been proposed as a risk factor, but serological support is lacking. The objective of this study was to investigate how age affects the EBV and HHV-6A associated risks of developing MS. METHODS: In this nested case-control study, Swedish biobanks were accessed to find pre-symptomatically collected blood samples from 670 individuals who later developed relapsing MS and 670 matched controls. A bead-based multiplex assay was used to determine serological response against EBV and HHV-6A. Conditional logistic regression was used to calculate odds ratios and 95% confidence intervals. RESULTS: Seropositivity against EBV exhibited a pattern where associations switched from a decreased risk of developing MS in the group below 20 years of age to an increased risk amongst individuals aged 20-29 and 30-39 years (p for trend 0.020). The age of transition was estimated to be 18.8 years. In contrast, HHV-6A was associated with increased MS risk in all age groups (total cohort odds ratio 2.1, 95% confidence interval 1.6-2.7). CONCLUSIONS: This study suggests EBV infection after adolescence and age independent HHV-6A infection as risk factors for MS.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 6 , Esclerose Múltipla , Adolescente , Estudos de Casos e Controles , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/epidemiologia , Herpesvirus Humano 4 , Humanos , Esclerose Múltipla/epidemiologia , Fatores de Risco
4.
Evol Med Public Health ; 2020(1): 2-11, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31976073

RESUMO

INTRODUCTION: How the long-chain fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in the diet permitted human brain evolution, and how much our brains need today to function optimally are still hot topics for debate. DHA and EPA are considered as semi-essential because only insufficient amounts can be produced from other nutrients, such that they must be ingested with the diet. However, the Dietary Reference Intake of DHA and EPA, or of fish containing these fatty acids, has not yet been established. Eating fish is often recommended and generally considered beneficial for health and cognitive development in children and adolescents. For this study, data from a large cohort study were analysed to assess the association between fish consumption and cognitive school performance in children and adolescents. METHODS: Data from the German cohort of children and adolescent health KiGGS, which was conducted 2003-06 and included more than 17 000 children, were analysed. Ordered logistic regressions were performed to test for associations between fish intake and school performance. Potential confounders were included in the models. RESULTS: A statistically significant association was found between an intake of 8 g of fish per day and the probability of increasing the final grade in German [odds ratio (OR) 1.193, 95% confidence interval (CI) 1.049-1.358] and mathematics (OR 1.16, 95% CI 1.022-1.317) by one point, compared to no or very limited fish consumption. For the outcome German, higher levels of fish intake also showed a positive effect. These relationships were not linear but tended to decrease again at higher doses of fish. DISCUSSION: Our result confirms previous reports of a positive association between fish intake and school performance. Interestingly, this relationship was not linear but tended to decrease again in the highest categories of fish intake. We hypothesize that mercury or other pollutants in the fish could be detrimental at high levels. As only half of all children met the minimal fish intake recommendations, fish consumption should be promoted more strongly in children to meet the minimal requirements of long-chain polyunsaturated fatty acids. LAY SUMMARY: Polyunsaturated fatty acids like DHA and EPA that are present in fish are essential for a healthy human brain development. We found a U-shaped association between fish intake and school performance in children. We hypothesize that mercury or other pollutants in the fish could be detrimental at high intake levels.

5.
J Dent Res ; 98(8): 879-887, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31282843

RESUMO

In epidemiologic studies, patients with head and neck squamous cell carcinoma (HNSCC) are classified mainly by the International Classification of Diseases (ICD) codes. However, some patients are of an unclear subsite, the "gray zone" cases, which could reflect ICD coding error, absence of primary subsite, or extensive primary tumors that cross over multiple subsites of the oral cavity and oropharynx. Patients with gray zone squamous cell carcinomas were compared with patients with oral cavity squamous cell carcinoma (OSCC) or oropharyngeal squamous cell carcinoma (OPSCC) and stratified by human papillomavirus (HPV) status that was determined by p16 immunostaining or HPV serology. Comparisons consisted of clinicodemographic features and prognostic outcomes presented by Kaplan-Meier curves and Cox proportional hazards regression models, reported as hazard ratios. There were 158 consecutive patients with gray zone HNSCC diagnosed at the Princess Margaret Cancer Center between 2006 and 2017: 66 had subsite coding discrepancies against the clinician's documentation ("discrepant" cases; e.g., the diagnosis by the clinician was OSCC, while the classification by ICD coding was OPSCC), while 92 were squamous cell carcinoma of unknown primary of the head and neck (SCCUPHN) after complete diagnostic workup. Comparators included 721 consecutive OSCC and 938 OPSCC adult cases. All HPV-positive cohorts (OPSCC, discrepant, and SCCUPHN) had similar clinicodemographic characteristics and better 3- and 5-y overall survival and disease-free survival than their HPV-negative counterparts. In contrast, HPV-negative discrepant cases had prognostic outcomes most similar to HPV-negative OPSCC cases, while HPV-negative SCCUPHN had survival outcomes most similar to those of patients with OSCC in this study. HPV-positive status can improve the classification of patients with unclear or discrepant oral/oropharyngeal subsite, an improvement over classification systems that are solely clinician defined or conducted through ICD coding. However, due to clinical practice, we could not make definitive reclassification for patients with HPV-negative gray zone HNSCC.


Assuntos
Carcinoma de Células Escamosas/classificação , Neoplasias de Cabeça e Pescoço/classificação , Neoplasias Orofaríngeas/classificação , Papillomaviridae , Infecções por Papillomavirus , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/virologia , Codificação Clínica , Feminino , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Classificação Internacional de Doenças , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/virologia , Adulto Jovem
6.
Ann Oncol ; 30(8): 1335-1343, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31185496

RESUMO

BACKGROUND: Human papillomavirus type 16 (HPV16)-E6 antibodies are detectable in peripheral blood before diagnosis in the majority of HPV16-driven oropharyngeal squamous cell carcinoma (OPSCC), but the timing of seroconversion is unknown. PATIENTS AND METHODS: We formed the HPV Cancer Cohort Consortium which comprises nine population cohorts from Europe, North America and Australia. In total, 743 incident OPSCC cases and 5814 controls provided at least one pre-diagnostic blood sample, including 111 cases with multiple samples. Median time between first blood collection and OPSCC diagnosis was 11.4 years (IQR = 6-11 years, range = 0-40 years). Antibodies against HPV16-E6 were measured by multiplex serology (GST fusion protein based Luminex assay). RESULTS: HPV16-E6 seropositivity was present in 0.4% of controls (22/5814; 95% CI 0.2% to 0.6%) and 26.2% (195/743; 95% CI 23.1% to 29.6%) of OPSCC cases. HPV16-E6 seropositivity increased the odds of OPSCC 98.2-fold (95% CI 62.1-155.4) in whites and 17.2-fold (95% CI 1.7-170.5) in blacks. Seropositivity in cases was more frequent in recent calendar periods, ranging from 21.9% pre-1996 to 68.4% in 2005 onwards, in those with blood collection near diagnosis (lead time <5 years). HPV16-E6 seropositivity increased with lead time: 0.0%, 13.5%, 23.7%, and 38.9% with lead times of >30 years (N = 24), 20-30 years (N = 148), 10-20 years (N = 228), and <10 years (N = 301 cases) (p-trend < 0.001). Of the 47 HPV16-E6 seropositive cases with serially-collected blood samples, 17 cases seroconverted during follow-up, with timing ranging from 6 to 28 years before diagnosis. For the remaining 30 cases, robust seropositivity was observed up to 25 years before diagnosis. CONCLUSIONS: The immune response to HPV16-driven tumorigenesis is most often detectable several decades before OPSCC diagnosis. HPV16-E6 seropositive individuals face increased risk of OPSCC over several decades.


Assuntos
Anticorpos Antivirais/sangue , Papillomavirus Humano 16/imunologia , Neoplasias Orofaríngeas/diagnóstico , Infecções por Papillomavirus/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Adulto , Idoso , Carcinogênese/imunologia , Estudos de Casos e Controles , Feminino , Seguimentos , Papillomavirus Humano 16/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/imunologia , Neoplasias Orofaríngeas/sangue , Neoplasias Orofaríngeas/imunologia , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/sangue , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Estudos Prospectivos , Proteínas Repressoras/imunologia , Soroconversão , Carcinoma de Células Escamosas de Cabeça e Pescoço/sangue , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Fatores de Tempo
7.
Obes Rev ; 15(8): 657-65, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24891155

RESUMO

Obesity is a major public health issue and an important contributor to the global burden of chronic disease and disability. Studies indicate that fish and omega-3 polyunsaturated fatty acids (n3-PUFA) supplements may help prevent cardiovascular and metabolic diseases. However, the effect of fish oil on body composition is still uncertain, so we performed a systematic review of randomized controlled trials and the first meta-analysis on the association between fish or fish oil intake and body composition measures. We found evidence that participants taking fish or fish oil lost 0.59 kg more body weight than controls (95% confidence interval [CI]: -0.96 to -0.21). Treatment groups lost 0.24 kg m(-2) (body mass index) more than controls (-0.40 to -0.08), and 0.49 % more body fat than controls (-0.97 to -0.01). Fish or fish oil reduced waist circumference by 0.81 cm (-1.34 to -0.28) compared with control. There was no difference for fat mass and lean body mass. Further research is needed to confirm or refute our findings and to reveal possible mechanisms by which n3-PUFAs might reduce weight.


Assuntos
Composição Corporal , Ácidos Graxos Ômega-3/administração & dosagem , Alimentos Marinhos , Tecido Adiposo , Animais , Índice de Massa Corporal , Peso Corporal , Bases de Dados Factuais , Suplementos Nutricionais , Óleos de Peixe/administração & dosagem , Peixes , Humanos , Obesidade/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Sensibilidade e Especificidade , Circunferência da Cintura
8.
Opt Express ; 22(8): 9574-84, 2014 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-24787845

RESUMO

We show that Fano resonances created by two 𝒫 𝒯 -symmetric nonlinear micro-resonators coupled to a waveguide, have line-shape and resonance position that depends on the direction of the incident light. We utilize these features in order to induce asymmetric transport, up to 47 dBs, in the optical C-window. Our theoretical proposal requires low input power and does not compromise the power or frequency characteristics of the output signal.

9.
Phys Rev Lett ; 110(23): 234101, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-25167495

RESUMO

A mechanism for asymmetric transport which is based on parity-time-symmetric nonlinearities is presented. We show that in contrast to the case of conservative nonlinearities, an increase of the complementary conductance strength leads to a simultaneous increase of asymmetry and transmittance intensity. We experimentally demonstrate the phenomenon using a pair of coupled Van der Pol oscillators as a reference system, each with complementary anharmonic gain and loss conductances, connected to transmission lines. An equivalent optical setup is also proposed.

10.
Hamostaseologie ; 24(3): 173-8, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15314702

RESUMO

Gene therapy is a new therapeutic approach which is tested in numerous diseases connected with either non or only limited therapeutic effects. This paper aims at discussing the actual state of the clinical development of gene-therapy which targets an approval by either the FDA or EMEA. Basis of all the figures and tables presented is a BioMedNet/Medline search reviewing all titles found under the keywords gene therapy and/or clinical development. The review period begins in the year 1992 and ends in 2002. Publications identified were sorted into the following categories: therapeutic areas with gene therapy activities; indications and diseases with gene-therapy activities; vectors used in gene therapy and clinical studies using gene therapy. Only in some indications like breast cancer, colorectal cancer, HIV, and cystic fibrosis a variety of clinical studies had been published indicating a serious attempt to develop the indication for approval. But most developments are still in phase I/II. In all other therapeutic areas no systematic continuous approach was identified. Clinical activities in cardiovascular diseases and in peripheral vascular diseases increased during the preceding five years compared other therapeutic areas.


Assuntos
Terapia Genética/tendências , Ensaios Clínicos como Assunto , Terapia Genética/economia , Humanos , MEDLINE , Apoio à Pesquisa como Assunto
11.
Res Nurs Health ; 24(5): 373-89, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11746067

RESUMO

The purpose of this pilot study was to evaluate the effectiveness of a parent-focused intervention program (COPE) on infant cognitive development and maternal coping. A randomized clinical trial was conducted with 42 mothers of low-birth-weight (LBW) premature infants hospitalized in a neonatal intensive care unit (NICU), with follow-up at 3 months' and 6 months' corrected ages. COPE mothers received the four-phase educational-behavioral program that began 2-4 days postbirth and continued through 1 week following discharge from the NICU. Comparison mothers received audiotaped information during the same four time frames. Results indicated that COPE infants had significantly higher mental development scores at a 3 months' corrected age (M = 100.3) than did the comparison infants (M = 93.9), and this difference widened at 6 months' corrected age, with COPE infants scoring 14 points higher. COPE mothers were significantly less stressed by the NICU sights and sounds and had significantly stronger beliefs about what behaviors and characteristics to expect from their premature infants. Findings from this study support the need for further testing of early NICU interventions with parents to determine their effectiveness on parental coping and infant developmental outcomes.


Assuntos
Adaptação Psicológica , Desenvolvimento Infantil , Cognição , Recém-Nascido de Baixo Peso , Relações Mãe-Filho , Educação de Pacientes como Assunto , Adolescente , Adulto , Criança Hospitalizada , Feminino , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Entrevistas como Assunto , Masculino , Projetos Piloto
13.
Ambul Outreach ; : 6-13, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11067446

RESUMO

The error prone health care system is complex, tightly coupled and hierarchical. Who's at fault when an error occurs? How do we keep patients safe and prevent errors in this error prone system? There will continue to be health care mistakes, it is inevitable in an error prone system but things can be done to increase patient safety. The communication between and among health care providers and patients that work toward building better relationship ties have demonstrated the potential for greater patient safety. In fact, starting from the discussion point of patient safety, rather than starting from error, has the most profound chance to benefit patients. An overview of efforts to increase patient safety through research and clinical practice are discussed. Ironically, examples of errors in health care have caught the attention of the American public. In the long run, patient safety must be the intrinsic cause for improvement. Many errors in health care are unknown and the total number may be unknowable. A well-known study from Harvard reported that about 4 percent of hospitalized patients had iatrogenic injuries; 13 percent of those were fatal (Leape et al, 1991). The principle investigator in that study, Dr. Lucien Leape, said "Errors are system flaws, not character flaws". In 95 percent of the cases, errors are not the result of carelessness or lack of concern. The worse errors are sometimes made by the best doctors and nurses (Leape et al, 1991). Although technology is helping in some ways, it is also causing a growing risk of new unexpected adverse events. This is a problem that must be addressed. Even though not a popular problem in health care, if not critically tackled, it will get worse in the future. This article examines: why this problem needs to be addressed, what has been done so far, and the major components of health care, systems, technology, and humans, that make it error prone and complex. This article will also examine these three areas of interest where mistakes are made.


Assuntos
Administração Hospitalar/normas , Erros Médicos/prevenção & controle , Gestão da Segurança/organização & administração , Humanos , Joint Commission on Accreditation of Healthcare Organizations , Gestão de Riscos/organização & administração , Estados Unidos
14.
Pharmacotherapy ; 18(3 Pt 2): 108S-115S; discussion 85S-86S, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9619495

RESUMO

Research into drug therapy for the acute treatment of ischemic stroke is now booming, and a number of promising drugs with very different mechanisms of action are at an advanced stage of development. Ideally, use of single agents or combinations of agents will result in favorable neurologic and functional outcomes for the majority of stroke patients. Given the current focus within our society on controlling health care costs, pharmacoeconomic tools will be important in determining which of these agents should achieve formulary acceptance. Cost-minimization analysis, cost-benefit analysis, cost-effectiveness analysis, and cost-utility analysis are all likely to be valuable methodologies to aid in decision making. More complex situations may require the use of decision-tree analysis.


Assuntos
Transtornos Cerebrovasculares/tratamento farmacológico , Árvores de Decisões , Quimioterapia Combinada , Farmacoeconomia , Humanos , Fármacos Neuroprotetores/uso terapêutico
16.
Curr Med Res Opin ; 13(5): 264-73, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7555035

RESUMO

In order to evaluate the pharmacokinetics and excretion of ramipril in man, 8 cholecystectomy patients aged between 53 and 68 years received 5 mg ramipril orally as a single dose. All patients had a T-drain inserted to permit bile collection; all gave their informed consent to participate in the trial. Serum samples were collected half-hourly until 2 hours, then hourly until 6 hours, then at 8, 10, 24 and 25 hours after intake. Urine was collected in 2-hour fractions until 8 hours, followed by a 4- and a 12-hour fraction. Bile was collected hourly until 6 hours, followed by a 6- and a 12-hour collecting fraction. Concentrations of ramipril and ramiprilat in serum, and determinations in urine and bile of ramipril, ramiprilat, ramipril glucuronide, ramiprilat glucuronide, diketopiperazine and diketopiperazine acid were made; total amounts excreted were calculated. Peak concentrations of ramiprilat in plasma (8.7 +/- 1.6 ng/ml) were reached after about 8 hours. AUC0-8 and AUC0-24-values were 36.5 and 111.9 ng.h/ml, respectively. Ramiprilat Cmax-concentrations were about 300-fold higher in bile than in plasma, the corresponding difference for ramipril between bile and plasma was about 4-fold. The main fractions excreted in the urine were diketopiperazine acid and ramiprilat amounting to 13.2 +/- 5.6 and 4.4 +/- 2.4%, respectively, of the dose administered. Only a very small fraction of the dose was excreted with urine as unchanged ramipril, on average 0.9 +/- 1.0%. The main fractions excreted in the bile were diketopiperazine acid, ramiprilat glucuronide and diketopiperazine, 9.0 +/- 5.3, 3.4 +/- 4.2 and 2.0 +/- 1.2% in 24 hours, respectively, of the dose administered. Only a negligible fraction of the dose (average 0.1 +/- 0.1%) was excreted with bile as unchanged ramipril. In conclusion, there is strong evidence that circulating ramipril and ramiprilat are eliminated by both the liver and the kidneys. For the patients studied it can be estimated from late collection periods that some 2/3 of circulating ramipril and ramiprilat are eliminated by the kidneys and 1/3 eliminated by the liver.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/metabolismo , Bile/metabolismo , Ramipril/análogos & derivados , Ramipril/metabolismo , Administração Oral , Idoso , Inibidores da Enzima Conversora de Angiotensina/farmacocinética , Biotransformação , Colecistectomia , Cromatografia Gasosa , Feminino , Humanos , Rim/metabolismo , Análise dos Mínimos Quadrados , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Ramipril/farmacocinética , Fatores de Tempo
17.
Br J Clin Pharmacol ; 38(4): 317-21, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7833220

RESUMO

1. The effect of icatibant (D-Arg-[Hyp3, Thi5, D-Tic7, Oic8] bradykinin) a potent B2-kinin receptor antagonist, was studied on bradykinin-induced vasodilation in the human forearm. 2. Eight healthy normotensive men were studied in a rising dose random-placebo controlled study. Placebo and icatibant (20, 50 and 100 micrograms kg-1 i.v.) were administered double-blind. Forearm blood flow was measured by venous occlusion plethysmography during rising dose brachial artery infusions of bradykinin (10-3,000 ng min-1) 60-90 min after placebo or icatibant. 3. Plasma concentrations of icatibant fell exponentially following each of three doses, up to the final measurement. Elimination half-lives calculated from linear regression of the mean data were 25, 27 and 29 min after 20, 50 and 100 micrograms kg-1 doses respectively. 4. Icatibant inhibited the effect of bradykinin (P < 0.001 at each dose of icatibant) in a dose-dependent manner. Bradykinin (100 ng min-1) increased mean blood flow in the infused arm by 238 +/- 31% when infused following placebo, by 112 +/- 21% after icatibant 20 micrograms kg-1, by 71 +/- 14% after icatibant 50 micrograms kg-1 and by 48 +/- 9% after icatibant 100 micrograms kg-1. 5. These results demonstrate that icatibant antagonises B2-receptor mediated vasodilation in human forearm resistance vessels. The findings provide a quantitative basis for future studies of the role of bradykinin in the response to angiotensin converting enzyme inhibitors and in circulatory disease.


Assuntos
Antagonistas de Receptores Adrenérgicos beta 2 , Antagonistas Adrenérgicos beta/farmacologia , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Vasodilatação/efeitos dos fármacos , Antagonistas Adrenérgicos beta/sangue , Antagonistas Adrenérgicos beta/farmacocinética , Adulto , Análise de Variância , Pressão Sanguínea/efeitos dos fármacos , Artéria Braquial/efeitos dos fármacos , Bradicinina/sangue , Bradicinina/farmacocinética , Antagonistas dos Receptores da Bradicinina , Relação Dose-Resposta a Droga , Método Duplo-Cego , Antebraço/irrigação sanguínea , Meia-Vida , Humanos , Infusões Intra-Arteriais , Infusões Intravenosas , Modelos Lineares , Masculino , Radioimunoensaio , Fluxo Sanguíneo Regional/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos
18.
J Hypertens ; 11(2): 217-21, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8385183

RESUMO

OBJECTIVE: To identify appropriate dosages of ramipril and hydrochlorothiazide (HCT) when given in combination once a day for the treatment of essential hypertension. DESIGN: A 2- or 4-week placebo run-in followed by 6-week, double-blind, parallel-group phase: 4 x 3 factorial (2.5, 5 and 10 mg ramipril; 12.5 and 25 mg HCT; all six combinations; placebo). SETTING: Office practice (21 centres). PATIENTS AND PARTICIPANTS: Patients with mild-to-moderate essential hypertension (World Health Organization stage I-II; supine diastolic blood pressure 100-115 mmHg in last 2 weeks of run-in): 581 enrolled, 534 randomly assigned to double-blind therapy and 517 completed. MAIN OUTCOME MEASURES: Reduction in supine and standing blood pressure. RESULTS: In pairwise comparisons, the combinations of 5 mg ramipril with 12.5 and 25 mg HCT and 10 mg ramipril with 12.5 mg HCT consistently produced significantly greater blood pressure reductions than their respective components. Response surface analyses were performed, and a stairstep model was constructed to characterize the shape of the dose-response surface. The combinations involving 5 and 10 mg ramipril with 12.5 and 25 mg HCT were again more effective than their components. Withdrawals and adverse effects were minimal for all treatments. A large drop in serum potassium was observed on 25 mg HCT, but not on combination therapy. Addition of ramipril appeared to reduce the hyperuricaemic effect of HCT. CONCLUSIONS: Several dosage combinations of ramipril plus HCT produced significantly greater blood pressure reductions than the monotherapies at the same dosages. Overall, the combination of 5 mg ramipril and 25 mg HCT gave the best mean reduction. Combination therapy with ramipril plus HCT was safe and effective for patients with mild-to-moderate essential hypertension.


Assuntos
Hidroclorotiazida/administração & dosagem , Hipertensão/tratamento farmacológico , Ramipril/administração & dosagem , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Hidroclorotiazida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Ramipril/uso terapêutico , Projetos de Pesquisa
19.
Clin Cardiol ; 16(1): 47-52, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8416760

RESUMO

In an open, multicenter extension of a short-term study, 159 patients with mild to moderate hypertension were treated with either ramipril monotherapy or a combination of ramipril and hydrochlorothiazide for up to 1 year. Patients started with either 5 mg ramipril once daily (responders in the short-term study) or a combination of ramipril 5 mg plus hydrochlorothiazide 25 mg once daily. The dose could be adjusted and nonresponders to ramipril monotherapy could have hydrochlorothiazide added. In the 38 patients treated with ramipril monotherapy, the largest drop in mean blood pressure (BP) had already occurred in the previous short-term study; from Week 2 in the long-term study, the BP remained stable with means below 150/90 mmHg. In the 83 patients treated with the combination for 50 weeks or more, mean BP continued to decrease until around Week 10 in the long-term study while therapy was being adjusted. Thereafter, it also remained stable with means below 150/85 mmHg. Both treatment groups showed good mean reductions at end point, as did the group of 38 patients treated with the combination for less than 50 weeks. High response rates (84-95%) were seen in all groups at end point. The combination was well tolerated and the efficacy of ramipril in combination with hydrochlorothiazide was maintained over the 1-year period of investigation.


Assuntos
Hidroclorotiazida/uso terapêutico , Hipertensão/tratamento farmacológico , Ramipril/uso terapêutico , Adulto , Idoso , Pressão Sanguínea/efeitos dos fármacos , Quimioterapia Combinada , Feminino , Humanos , Hidroclorotiazida/administração & dosagem , Hidroclorotiazida/efeitos adversos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Ramipril/administração & dosagem , Ramipril/efeitos adversos
20.
J Cardiovasc Pharmacol ; 22 Suppl 9: S36-42, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7514239

RESUMO

Thirteen patients with chronic congestive heart failure of NYHA class II-III received multiple doses (14 days) of ramipril (5 mg once daily); the concentrations of ramipril and ramiprilat in plasma, as well as ramipril, ramiprilat, glucuronides, diketopiperazine, and diketopiperazine acid in urine were measured at various times for 14 days. One patient dropped out after the first day due to hypotension and another who accidentally received another ACE inhibitor additionally was excluded, so that 11 patients completed the study. Ramipril and ramiprilat in plasma were determined by radioimmunoassay, and ramipril and its metabolites in urine were measured by gas chromatography in the laboratories of Hoechst AG. Peak concentrations of the active substance ramiprilat were reached after about 4 h and amounted to 22.3 +/- 11.1 ng/ml after the first dose, and a peak concentration of 26.6 +/- 10.0 ng/ml was observed 2.5 +/- 1.4 h on average after administration on day 14. Practically no accumulation was observed for ramiprilat; the AUD (0-24 h) values increased from 191.3 +/- 83.1 ng.h/ml for the first study day to 238.3 +/- 98.0 ng.h/ml for day 14. As expected, only very small fractions of the dose were excreted with urine as unchanged ramipril and ramipril glucuronide. Ramiprilat is excreted with urine to a larger extent than is rampiril--on average 6.6 +/- 3.0% on the first day and 12.2 +/- 3.8% on day 14. The total amount excreted increased by 34% on average, and was mainly due to an increased ramiprilat excretion.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Ramipril/administração & dosagem , Ramipril/farmacocinética , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Inibidores da Enzima Conversora de Angiotensina/sangue , Esquema de Medicação , Humanos , Pessoa de Meia-Idade , Radioimunoensaio , Ramipril/análogos & derivados , Ramipril/sangue
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