Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-38898741

RESUMO

BACKGROUND: Serum creatinine is used as initial test to derive eGFR and confirmatory testing with serum cystatin C is recommended when creatinine-based eGFR is considered less accurate due to deviant muscle mass. Low muscle mass is associated with increased risk of premature mortality. However, the associations of serum creatinine and cystatin C with muscle mass and mortality remain unclear and require further investigation to better inform clinical decision-making. METHODS: We included 8437 community-dwelling adults enrolled in the Dutch PREVEND study and 5033 in the US NHANES replication cohort. Associations of serum creatinine and/or cystatin C with muscle mass surrogates and mortality were quantified with linear and Cox proportional hazards regression, respectively. Missing observations in covariates were multiply imputed using Substantive Model Compatible Fully Conditional Specification. RESULTS: Mean (SD) age of PREVEND and NHANES participants (50% and 48% male) were 49.8 (12.6) and 48.7 (18.7) years, respectively. Median (Q1-Q3) serum creatinine and cystatin C were 71 (61-80) and 80 (62-88) µmol/L and 0.87 (0.78-0.98) and 0.91 (0.80-1.10) mg/L, respectively. Higher serum creatinine was associated with greater muscle mass, while serum cystatin C was not associated with muscle mass. Adjusting both markers for each other strengthened the positive relationship between serum creatinine and muscle mass and revealed an inverse association between serum cystatin C and muscle mass. In the PREVEND cohort, 1636 (19%) deaths were registered over a median follow-up of 12.9 (5.8-16.3) years with a 10-year mortality rate (95% CI) of 7.6% (7.1-8.2%). In the NHANES, 1273 (25%) deaths were registered over a median follow-up of 17.9 (17.3-18.5) years with a 10-year mortality rate of 13.8% (12.8-14.7%). Both markers were associated with increased mortality. Notably, when adjusted for each other, higher serum creatinine was associated with decreased mortality, while the association between serum cystatin C and increased mortality strengthened. The shapes of the associations in the PREVEND study and NHANES were almost identical. CONCLUSIONS: The strong association between serum creatinine and muscle mass challenges its reliability as GFR marker, necessitating a more cautious approach in its clinical use. The minimal association between serum cystatin C and muscle mass supports its increased use as a more reliable alternative in routine clinical practice.

4.
Climacteric ; 25(3): 220-227, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34608830

RESUMO

Weight gain is a frequent problem in perimenopausal and postmenopausal women. Cimicifuga racemosa (CR) is a popular treatment option for menopausal symptoms. The aim of this review was to investigate whether there is scientific evidence that CR causes weight gain. We searched our database for medically confirmed, spontaneous adverse events regarding weight gain, literature for case reports and randomized controlled trials. Thirty cases in total were spontaneously reported in 15 years. The causality was not considered certain/likely in any of the cases. A nurse (consumer) assessed the causality as possible. Only one case was published in the literature. However, no change in body fat composition was reported, and the causality seems unlikely. Of the 31 identified studies, 17 were double-blind placebo-controlled, five were double-blind reference-controlled and nine were open reference-controlled. In total, 1839 women were treated with CR for up to 12 months. Two studies reported weight gain as an adverse event; however, no significant differences in weight changes were observed between the groups. One case of weight gain (about 2 kg) was reported, but the authors did not specify in which treatment group. In conclusion, this study provides no scientific evidence that the use of Cimicifuga racemosa causes weight gain in menopausal women.


Assuntos
Cimicifuga , Cimicifuga/efeitos adversos , Feminino , Humanos , Masculino , Menopausa , Fitoterapia/efeitos adversos , Extratos Vegetais/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Aumento de Peso
5.
Plants (Basel) ; 10(7)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34371565

RESUMO

Genome size is one of the fundamental cytogenetic features of a species, which is critical for the design and initiation of any genome sequencing projects and can provide essential insights in studying taxonomy, cytogenetics, phylogenesis, and evolutionary studies. However, this key cytogenetic information is almost lacking in the endemic species Reseda pentagyna and the locally rare species Reseda lutea in Saudi Arabia. Therefore, genome size was analyzed by propidium iodide PI flow cytometry and compared to k-mer analysis methods. The standard method for genome size measures (flow cytometry) estimated the genome size of R. lutea and R. pentagyna with nuclei isolation MB01 buffer were found to be 1.91 ± 0.02 and 2.09 ± 0.03 pg/2 °C, respectively, which corresponded approximately to a haploid genome size of 934 and 1.022 Mbp, respectively. For validation, K-mer analysis was performed on both species' Illumina paired-end sequencing data from both species. Five k-mer analysis approaches were examined for biocomputational estimation of genome size: A general formula and four well-known programs (CovEST, Kmergenie, FindGSE, and GenomeScope). The parameter preferences had a significant impact on GenomeScope and Kmergenie estimates. While the general formula estimations did not differ considerably, with an average genome size of 867.7 and 896. Mbp. The differences across flow cytometry and biocomputational predictions may be due to the high repeat content, particularly long repetitive regions in both genomes, 71% and 57%, which interfered with k-mer analysis. GenomeScope allowed quantification of high heterozygosity levels (1.04 and 1.37%) of R. lutea and R. pentagyna genomes, respectively. Based on our observations, R. lutea may have a tetraploid genome or higher. Our results revealed fundamental cytogenetic information for R. lutea and R. pentagyna, which should be used in future taxonomic studies and whole-genome sequencing.

6.
Clin Oral Investig ; 24(10): 3513-3518, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32691297

RESUMO

OBJECTIVES: The aim of this study was to test the effects of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) crème, or MI Paste™ (MIP), on nicotine-induced Streptococcus mutans biofilm. The experiment utilized S. mutans biofilm assays with varying concentrations of nicotine and MIP aqueous concentrate levels. First hand exposure to nicotine has been demonstrated to significantly increase S. mutans biofilm formation, while the active component, CPP-ACP, in MIP has been shown to reduce S. mutans biofilm formation. MATERIALS AND METHODS: A 24-h culture of S. mutans UA159 in microtiter plates were treated with varying nicotine concentrations (0-32 mg/ml) in Tryptic Soy Broth supplemented with 1% sucrose (TSBS) with or without MIP aqueous concentrate. A spectrophotometer was used to determine total growth absorbance and planktonic growth. The microtiter plate wells were washed, fixed, and stained with crystal violet dye and the absorbance measured to determine biofilm formation. RESULTS: The presence of MIP aqueous concentrate inhibits nicotine-induced S. mutans biofilm formation at different concentrations of nicotine (0-32 mg/ml). CONCLUSION: The results demonstrated nicotine-induced S. mutans biofilm formation is decreased in the presence of MIP. This provides further evidence about the cariostatic properties of CPP-ACP, the active soluble ingredient in the MIP, and reconfirms the harmful effects of nicotine. CLINICAL SIGNIFICANCE: Smokers may gain dual benefits from the use of MIP, as a remineralization agent and as a cariostatic agent, by inhibiting nicotine-induced S. mutans biofilm formation.


Assuntos
Streptococcus mutans , Biofilmes , Fosfatos de Cálcio , Caseínas , Nicotina , Fosfopeptídeos
7.
J Med Food ; 23(10): 1093-1101, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32286896

RESUMO

Three new galactomannan components designed as AANP-1, AANP-3, and AAAP-7 were isolated from previously purified Aloe arborescence polysaccharide fractions, using ion-exchange, gel filtration, and preparative chromatographic techniques. Based on Fourier transform-infrared, one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy, the main backbone of AANP-1 elucidated as (1 → 4)-linked_α-d-deoxyGalp, (1 → 4) d-Manp, and ß-d-2-glup. The sugar residue sequence of AANP-3 was (1 → 4)-linked ß-d-NHAC-GAlp with ß-d-AcManp side chain that attached to O-4 position. The AAAP-7 repeated units were (1 → 4) d-Manp linked with (1 → 4) d-Galp interspersed with (1 → 3)-α-Manp. The results of high performance size-exclusion chromatography indicated that the approximate molecular weights of AANP-1, AANP-3, and AAAP-7 were 4.2, 2.4, and 2.5 kDa, respectively. The cytokine modulation assay revealed that the isolated components promoted a remarkable release of interleukin (IL)-12 and tumor necrosis factor alpha in comparison with the negative control group, whereas potent significant induction of IL-2 and interferon gamma was detected more than the positive control phytohemagglutinin (P < .05). This is the first report for isolation galactomannans from Aloe arborescence. Moreover, this finding could provide new insights for exploring the biological modifier mechanism in correlation with the knowledge of structural configuration.


Assuntos
Aloe/química , Citocinas/metabolismo , Mananas/química , Mananas/farmacologia , Sequência de Carboidratos , Células Cultivadas , Galactose/análogos & derivados , Humanos , Leucócitos Mononucleares/efeitos dos fármacos
8.
J Med Food ; 23(8): 895-901, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31976801

RESUMO

Plant polysaccharides gained extended scientific attention for their immunomodulatory effect. However, few scientific studies structurally defined polysaccharides in relation to their biological modifier response. Therefore, the study explored the effect of structurally identified isolated macromolecules from Aloe arborescens against cytokine modulation (interferon [IFN-γ], interleukins [IL-2 and IL-12], and tumor necrosis factor [TNF-α]) in vitro. The structures were elucidated by GC, GPC, FT-IR spectroscopy, 1D NMR, COSY, HMBC, and HSQC. Two acetylated glucomannans (AANP4 and AAAP6), one deoxy-glucogalactan (AANP5), and one deoxy-N-acetyl-[1-4]-galactosamine (AANP2) were isolated. The results showed significant induction for all cytokines and the most potent component was AAAP6; acetylated phenolic glucomannan with a (1 → 3)-linked glucose-mannose and (1 → 4)-linked mannose backbone, which stimulated IL-12 by more than 10-fold compared with phytohemagglutinin (positive control). In conclusion, A. arborescens polysaccharides could be a landmark for development of effective immunotherapeutics against cancer and chronic inflammatory conditions.


Assuntos
Aloe/química , Galactosamina/química , Fatores Imunológicos/química , Polissacarídeos/química , Acetilação , Estrutura Molecular , Compostos Fitoquímicos/química , Folhas de Planta/química , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Climacteric ; 22(4): 339-347, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30626212

RESUMO

Endocrine therapy in breast cancer survivors can cause severe 'climacteric' symptoms, which may compromise therapy adherence. To determine whether such symptoms can be treated with herbal medication containing black cohosh in the form of isopropanolic Cimicifuga racemosa extract (iCR) alone or in fixed combination with St John's wort (Hypericum perforatum [HP]) (iCR + HP), a systematic literature search was conducted. Results were viewed in relation to experimental data and metabolism of endocrine therapies. Most breast cancer survivors receiving endocrine therapy experienced reductions in climacteric symptoms under iCR/iCR + HP. Tamoxifen's interference potential may be countered by using higher iCR doses or iCR + HP. No estrogen-like effects at the breast or on hormones were seen. After breast cancer, even if receiving tamoxifen, patients using iCR/iCR + HP had significantly increased recurrence-free survival rates compared to non-users. These results are substantiated by experimental data demonstrating antiproliferative and anti-invasive effects of iCR in breast cancer cells and enhancement of the antineoplastic effects of tamoxifen. There are no known clinical interactions for iCR and HP with endocrine therapies. The HP extract used in iCR + HP did not exhibit any clinically relevant interaction potential. In conclusion, with its positive benefit-risk profile, iCR/iCR + HP may offer a safe non-hormonal therapeutic option for breast cancer survivors receiving endocrine therapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Cimicifuga , Hypericum , Extratos Vegetais/uso terapêutico , Neoplasias da Mama/patologia , Quimioterapia Combinada , Feminino , Humanos , Menopausa , Fitoterapia , Extratos Vegetais/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco
11.
Artigo em Inglês | MEDLINE | ID: mdl-28535423

RESUMO

Aloe arborescens Miller (Family Asphodelaceae) is a member of genus Aloe, which is used in traditional medicine to cure various diseases. The extracts of the plant have been reported to possess anticancer, immunomodulator, antidiabetic, anti-inflammatory and antioxidant activities. The phytochemical investigations have revealed diverse chemical constituents, including phenolics [anthraquinones, anthrones, pyrones, chromones and coumarins], polysaccharides [arborans [(1-4) linked glucomannans, polysaccharide (A, B and C): (A: a linear (1-6)-O-α-glucan, B: a branching (1-2)-O-l-arabinose with (1-2)-O-d-galactose linkages and C: (1-4)-O-ß-mannan with 18% acetyl group)]], glycoproteins and carboxypeptidase enzyme. There are many reports, describing the different methodologies developed to perform chemical analysis as well as, separation, detection and identification of these constituents. Different chromatographic techniques were applied such as gas chromatography (GC), high-performance liquid chromatography (HPLC), liquid chromatography-electrospray ionization coupled with mass spectroscopy (LC-ESI/MS/MS) and gel filtration chromatography. Also the isolated compounds were identified based on the spectroscopic analysis; ultraviolet-visible spectroscopy (UV-vis), infra-red spectroscopy (IR), mass spectroscopy (MS) and nuclear-magnetic resonance (NMR). This study aims to pinpoint the active components besides finding out new structural leads for future drugs. Therefore, the review is targeted to provide evidence reported in the relevant literature on qualitative and quantitative research to assist scientists in isolation and characterization of bioactive compounds in A. arborescens.


Assuntos
Aloe/química , Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais , Glicoproteínas , Fenóis , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
12.
J Med Food ; 20(5): 491-501, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28414560

RESUMO

Different polysaccharides were isolated from the leaves of Aloe arborescens using the gradient power of hydrogen followed by antitumor and immunomodulatory assay. The total polysaccharide content of different fractions, water-soluble polysaccharide (WAP), acid-soluble polysaccharide (ACP), and alkaline-soluble polysaccharide (ALP), was estimated using a phenol-sulfuric acid spectrophotometric method. WAP possessed a higher content of mannose and glucose than either ACP or ALP. In vitro antitumor activity was investigated in three different cancer cell lines, and in vitro immunomodulatory potential was assessed through phagocytosis and lymphocyte transformation assay. The results showed that WAP and ALP exhibited the most significant cytotoxicity against HepG2 human liver cancer cells, with IC50 values of 26.14 and 21.46 µg/mL, respectively. In contrast, ALP was able to enhance lymphocyte transformation, whereas WAP had the most potent phagocytic activity. Molecular weight, total sugar and uronic acid content, Fourier transform-infrared analysis, and linkage type of bioactive polysaccharides were investigated. These findings revealed that the potential antitumor activity of the natural agents WAP and ALP was through an immunomodulation mechanism, which verifies the use of the plant as adjuvant supplement for cancer patients suffering immunosuppression during chemotherapy.


Assuntos
Aloe/química , Fatores Imunológicos/farmacologia , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Linhagem Celular Tumoral , Humanos , Fatores Imunológicos/química , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Extratos Vegetais/química , Folhas de Planta/química , Polissacarídeos/química
13.
Phytother Res ; 29(12): 1858-67, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26768148

RESUMO

Since ancient times, plants and herbal preparations have been used as medicine. Research carried out in the last few decades has verified several such claims. Aloe arborescens Miller, belonging to the Aloe genus (Family Asphodelaceae), is one of the main varieties of Aloe used worldwide. The popularity of the plant in traditional medicine for several ailments (antitumor, immunomodulatory, antiinflammatory, antiulcer, antimicrobial and antifungal activity) focused the investigator's interest on this plant. Most importantly, the reported studies have shown the plant effectiveness on various cancer types such as liver, colon, duodenal, skin, pancreatic, intestinal, lung and kidney types. These multiple biological actions make Aloe an important resource for developing new natural therapies. However, the biological activities of isolated compounds such as glycoprotein, polysaccharides, enzyme and phenolics were insufficient. Considering all these, this contribution provides a systematic review outlining the evidence on the biological efficacy of the plant including the pharmacology and the related mechanisms of action, with specific attention to the various safety precautions, and preclinical and clinical studies, indicating the future research prospects of this plant.


Assuntos
Aloe/química , Extratos Vegetais/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Ensaios Clínicos como Assunto , Humanos , Lectinas/química , Fenóis/química , Plantas Medicinais/química , Polissacarídeos/química
14.
BMC Emerg Med ; 11: 3, 2011 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-21310024

RESUMO

BACKGROUND: The Canadian Emergency Department Triage and Acuity Scale (CTAS) is a well recognized and validated triage system that prioritizes patient care by severity of illness. The aim of this study was to describe the results of Emergency Department (ED) waiting times after the implementation of the CTAS in a major tertiary care hospital emergency department outside of Canada. METHODS: A total of 1206 charts were randomly selected and retrospectively reviewed for triage performance. The indicators were: time to triage, triage duration, waiting time to be evaluated by a physician, and proportion of patients who left without being seen by a physician. Waiting times were stratified by triage level and reported as fractile response rates. RESULTS: The approximate time to triage was ≤ 10 minutes for 71% and ≤ 15 minutes for 82.8% of the patients. Fifty-three percent (53.5%) completed their triage process within 5 minutes. Waiting times evaluated by a physician was 100% within CTAS time objectives in category I patients, however, this was not the case for the other 4 categories. The overall left without being seen (LWBS) rate was 9.8%; 11.9% were in Level III, 20.3% in Level IV, and 67.8% in Level V. Median length of stay (LOS) was 144 minutes for the study sample as a whole. CONCLUSION: The CTAS may be adapted, with achievable objectives, in hospitals outside Canada as well. Time to see physician, total LOS, and LWBS are effective markers of ED performance and the quality of triage. Registration-to-physician time (RTP) and LOS profiles, stratified by triage level, are essential indicative markers for ED performance and should be used in improving patients flow through collaborative efforts.


Assuntos
Serviço Hospitalar de Emergência/normas , Triagem/métodos , Triagem/normas , Canadá , Humanos , Tempo de Internação/estatística & dados numéricos , Padrões de Prática em Enfermagem , Padrões de Prática Médica , Indicadores de Qualidade em Assistência à Saúde , Estudos Retrospectivos , Arábia Saudita , Tempo
15.
Med Oncol ; 27(3): 571-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19526202

RESUMO

The objective of this study is to evaluate the efficacy and safety profile of the doxorubicin followed by cisplatin/docetaxel as primary chemotherapy for patients with locally advanced breast cancer (LABC). For this evaluation, 59 patients with LABC (T2-T4, N0-N2, M0) received three cycles of doxorubicin, followed by three cycles of cisplatin/docetaxel and followed by definitive surgery and locoregional radiotherapy with or without tamoxifen. The primary end point was pathologic complete response (pCR) in breast and axilla. Fifty-nine patients were evaluable for analysis: median age: 41 years, premenopausal: 68%, median tumor size: 6.0 cm (4-10), Stage IIB: 32% and IIIA/IIIB: 68%, both ER/PR positive: 53%, Her2/neu (3+) by IHC staining: 29%. Clinical complete response was seen in 44%, and clinical partial response was seen in 56%. Breast conserving surgery was performed in 44%, and MRM in 56%. pCR in the breast was 30.5%, in axilla was 37%, and pCR in both breast and axilla was 24%. Overall at follow-up of 60 months, the disease-free (DFS) and overall survival (OS) were 70 and 82%, respectively. The DFS and OS of patients who achieved complete pathologic response in breast and axilla were 78 and 100%, respectively, while 14 patients relapsed of which 46% were Her2 positive. Sequential combination of doxorubicin followed by docetaxel/cisplatin is a safe, feasible, and active combination, which offers the possibility of conservative surgery and is associated with high clinical and pathologic response rates, with promising and encouraging survival outcomes.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Carcinoma/tratamento farmacológico , Terapia Neoadjuvante , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Carcinoma/patologia , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada , Intervalo Livre de Doença , Docetaxel , Doxorrubicina/administração & dosagem , Estrogênios , Feminino , Genes erbB-2 , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Mastectomia Radical Modificada , Mastectomia Segmentar , Pessoa de Meia-Idade , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias Hormônio-Dependentes/patologia , Progesterona , Estudos Prospectivos , Radioterapia Adjuvante , Tamoxifeno/administração & dosagem , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Resultado do Tratamento , Adulto Jovem
16.
Contemp Clin Trials ; 29(5): 720-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18571991

RESUMO

BACKGROUND: The human body exhibits a variety of biological rhythms. There are patterns that correspond, among others, to the daily wake / sleep cycle, a yearly seasonal cycle and, in women, the menstrual cycle. Sine/cosine functions are often used to model biological patterns for continuous data, but this model is not appropriate for analysis of biological rhythms in failure time data. METHODS: We consider a method appropriate for analysis of biological rhythms in clinical trials. We present a method to provide an estimate and confidence interval of the time when the minimum hazard is achieved. A motivating example from a clinical trial of adjuvant of pre-menopausal breast cancer patients provides an important illustration of the methodology in practice. RESULTS: Adapting the Cosinor method to the Weibull proportional hazards model is proposed as useful way of modeling the biological rhythm data. It presents a method to estimate the time that achieves the minimum hazard along with its associated confidence interval. The application of this technique to the breast cancer data revealed that the optimal day for pre-resection incisional or excisional biopsy of 28-day cycle (i.e. the day associated with the lowest recurrence rate) is day 8 with 95% CI 5-10. We found that older age, fewer positive nodes, smaller tumor size, and experimental treatment are important prognostic factors of longer relapse-free survival. CONCLUSIONS: The analysis of biological/circadian rhythms is usually handled by Cosinor rhythmometry method. However, in FTD this is simply not possible. In this case, we propose to adapt the Cosinor method to the Weibull proportional hazard model. The advantage of the proposed method is its ability to model survival data. This method is not limited to breast cancer data, and may be applied to any biological rhythms linked to right censored data.


Assuntos
Neoplasias da Mama/fisiopatologia , Neoplasias da Mama/cirurgia , Ritmo Circadiano , Ensaios Clínicos como Assunto , Ciclo Menstrual , Pré-Menopausa , Adulto , Neoplasias da Mama/mortalidade , Feminino , Humanos , Modelos Estatísticos
17.
J Circadian Rhythms ; 4: 14, 2006 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-17090302

RESUMO

BACKGROUND: The human body exhibits a variety of biological rhythms. There are patterns that correspond, among others, to the daily wake/sleep cycle, a yearly seasonal cycle and, in women, the menstrual cycle. Sine/cosine functions are often used to model biological patterns for continuous data, but this model is not appropriate for analysis of biological rhythms in failure time data. METHODS: We adapt the cosinor method to the proportional hazards model and present a method to provide an estimate and confidence interval of the time when the minimum hazard is achieved. We then apply this model to data taken from a clinical trial of adjuvant of pre-menopausal breast cancer patients. RESULTS: The application of this technique to the breast cancer data revealed that the optimal day for pre-resection incisional or excisional biopsy of 28-day cycle (i. e. the day associated with the lowest recurrence rate) is day 8 with 95% confidence interval of 4-12 days. We found that older age, fewer positive nodes, smaller tumor size, and experimental treatment were predictive of longer relapse-free survival. CONCLUSION: In this paper we have described a method for modeling failure time data with an underlying biological rhythm. The advantage of adapting a cosinor model to proportional hazards model is its ability to model right censored data. We have presented a method to provide an estimate and confidence interval of the day in the menstrual cycle where the minimum hazard is achieved. This method is not limited to breast cancer data, and may be applied to any biological rhythms linked to right censored data.

18.
Phytomedicine ; 12(10): 715-22, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16323289

RESUMO

The aim of this study was to verify the efficacy and safety of an herbal medication containing an extract of a mixture of Baptisiae tinctoriae radix, Echinaceae pallidae/purpureae radix and Thujae, occidentalis herba (SB-TOX) in the treatment of upper respiratory tract infections (URIs), and to test whether SB-TOX's clinical efficacy is dose dependent. A total of 91 adults (mean age 42.1 +/- 13.0 years) were randomised to receive 19.2 mg of SB-TOX (n=31), 9.6 mg SB-TOX (n=29) or placebo (n=31) three times daily for 3-12 days. Since a "running nose" is the main symptom of a common cold, the total number of facial tissues used throughout the clinical duration of their cold was the primary efficacy parameter. In the intention-to-treat analysis, this total number of tissues decreased with increasing extract dose. The slope across groups according to the Jonckheere test was significant (p = 0.0259). In the high-dose group, the standardised effect size delta/SD was 0.46 compared with placebo. Time to relevant improvement in cold symptoms (measured as the time until less than 30 tissues per day were used) was 1.1 days (95% CI 0.52; 1.67), 0.76 days (95% CI 0.28; 1.24) and 0.52 days (95% CI 0.22; 0.82) in the placebo, low-dose and high-dose groups, respectively (p(LogRank) = 0.0175). No adverse events were reported. This study demonstrates the efficacy and safety of SB-TOX in the treatment of URIs, and that its efficacy is dose dependent.


Assuntos
Resfriado Comum/tratamento farmacológico , Fitoterapia , Extratos Vegetais/administração & dosagem , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Echinacea , Fabaceae , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/efeitos adversos , Estudos Prospectivos , Thuja , Resultado do Tratamento
19.
Am J Physiol ; 270(5 Pt 2): R955-62, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8928926

RESUMO

We examined the impact of alkali therapy on myocardial contractility in a model of myocardial ischemia in dogs using direct measurements of myocardial contractile function. Myocardial ischemia in the left anterior descending (LAD) artery territory was induced using a perfusion circuit from the internal carotid artery to the LAD artery. Myocardial contractile function was assessed using sonomicrometry for measurement of percent systolic shortening (%SS), preload recruitable stroke work (PRSW) slope, and end-systolic pressure-length relationship (ESPLR) area. Because the blood flow in LAD artery was diminished by approximately 70%, there was a significant decrease in O2 delivery and uptake by the ischemic myocardium. Ischemia led to a significant fall in LAD regional contractile function with %SS decreasing from 15 +/- 2 to 7 +/- 2%, PRSW slope from 82 +/- 10 to 37 +/- 5 mmHg, and ESPLR area from 121 +/- 2 to 48 +/- 14 mmHg.mm (P < 0.05). In six dogs, the intracoronary administration of NaHCO(3) resulted in a significant increase in pH in LAD arterial and venous blood. There was, however, no significant increase in %SS (6 +/- 2), PRSW slope (43 +/- 10 mmHg), or ESPLR area (60 +/- 13 mmHg.mm). Since administration of NaHCO(3) resulted in a significant increase in PCO2 in LAD arterial and venous blood, similar experiments were carried out in five dogs, but with the intracoronary infusion of the amine buffer THAM [tris(hydroxymethyl)aminomethane (Tris) buffer; 2-amino-2-hydroxyl-1,3-propandiol] instead of NaHCO3. Although administration of THAM resulted in a significant increase in pH and a significant decrease in PCO2, in both LAD arterial and venous blood, there was no significant improvement in any of the parameters used to assess myocardial contractile function. In conclusion, administration of alkali (NaHCO3 or THAM) does not enhance the contractile function of the ischemic myocardium.


Assuntos
Contração Miocárdica/efeitos dos fármacos , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/fisiopatologia , Bicarbonato de Sódio/uso terapêutico , Trometamina/uso terapêutico , Álcalis/uso terapêutico , Animais , Circulação Coronária/efeitos dos fármacos , Vasos Coronários/fisiopatologia , Cães , Hemodinâmica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Isquemia Miocárdica/sangue , Consumo de Oxigênio/efeitos dos fármacos
20.
Ann Thorac Surg ; 59(5): 1187-91, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7733718

RESUMO

Larger numbers of microemboli detected by transcranial Doppler echocardiography have been linked to adverse neuropsychological outcome after coronary artery bypass grafting. Differences in neurologic outcome have been attributed to different cardioplegia techniques. Transcranial Doppler-detected microembolic events were recorded during coronary artery bypass grafting using different cardioplegia techniques. Patients received cold antegrade (n = 20), warm antegrade (n = 17), or warm retrograde (n = 20) cardioplegia. Continuous monitoring was divided into stages: aortic cannulation, initiation of cardiopulmonary bypass, aortic cross-clamping, aortic declamping and decannulation until chest closure. Rate of embolic events and number of total and immediate embolic events were tabulated. Total embolic events ranged from 22 to 2,072 per patient and were similar among groups. The rate and total at each stage were similar. Total embolic events were highest during aortic clamping; the rate was highest at initiation of bypass. The immediate embolic events were higher in the warm retrograde group than both antegrade groups at aortic declamping. In summary, a high total and rate of embolic events were detected and differences between cardioplegia techniques were detected.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Parada Cardíaca Induzida/efeitos adversos , Embolia e Trombose Intracraniana/etiologia , Ponte de Artéria Coronária/métodos , Ecoencefalografia , Feminino , Parada Cardíaca Induzida/métodos , Humanos , Embolia e Trombose Intracraniana/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ultrassonografia Doppler Transcraniana
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA