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1.
BMC Pulm Med ; 18(1): 120, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30029599

RESUMEN

BACKGROUND: Vitamin D deficiency has been linked to an increased risk of asthma. This study aimed to quantify the effect of early life vitamin D status on asthma and wheeze later in life. METHODS: PubMed, Embase, CINAHL, and CNKI databases, the Cochrane Central Register of Controlled Trials, and Google Scholar were searched up to July 2017. We included randomized controlled trials (RCTs) and cohort studies with vitamin D level in blood (maternal or cord or infant) or intake (maternal intake during pregnancy or infant intake) and asthma and/or wheeze. Two reviewers independently extracted data. Fixed- and random-effects models were used to summarize the risk estimates of comparisons between highest vs. lowest vitamin D categories. RESULTS: Of the 1485 studies identified, three RCTs and 33 cohort studies were included. We did not include the RCTs (1619 participants) in the meta-analysis as the comparators and outcome definitions were heterogenous. Three RCTs reported a non-statistically significant effect of vitamin D supplementation during pregnancy on offspring wheeze/asthma at 3 years of age. Pooled estimates of cohort studies suggest no association between antenatal blood vitamin D levels or vitamin D intake and offspring asthma assessed either > 5 years or ≤ 5 years. The estimate for blood vitamin D remained unchanged when two studies assessing asthma in adulthood were excluded, but a significant inverse association emerged between vitamin D intake and childhood asthma. We found no association between antenatal vitamin D level and wheeze. On the other hand, vitamin D intake during pregnancy may have a protective effect against wheeze. CONCLUSIONS: The pooled estimates from cohort studies show no association between antenatal blood vitamin D level and asthma/wheeze in later life. Whereas, the pooled estimates from cohort studies suggest that antenatal vitamin D intake may have an effect on childhood asthma > 5 years or childhood wheeze. The inconsistent results from studies assessing vitamin D either in blood or intake may be explained by previously reported non-linear association between blood vitamin D3 and childhood asthma. Further trials with enough power and longer follow-up time should be conducted to confirm the results.


Asunto(s)
Asma/sangre , Complicaciones del Embarazo/prevención & control , Deficiencia de Vitamina D/prevención & control , Vitamina D/sangre , Vitamina D/farmacología , Asma/fisiopatología , Preescolar , Estudios de Cohortes , Suplementos Dietéticos , Femenino , Humanos , Embarazo , Ruidos Respiratorios/etiología
2.
Birth ; 44(3): 281-289, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28321896

RESUMEN

BACKGROUND: Tea, a common beverage, has been suggested to exhibit a number of health benefits. However, one of its active ingredients, caffeine, has been associated with preterm birth and low birthweight. We investigated whether tea consumption during early pregnancy is associated with an increased risk of preterm birth and abnormal fetal growth. METHODS: A total of 8775 pregnant women were included from the Born in Guangzhou Cohort Study. Tea consumption (type, frequency, and strength) during their first trimester and social and demographic factors were obtained by way of questionnaires administered during pregnancy. Information on birth outcomes and complications during pregnancy was obtained from hospital medical records. RESULTS: Overall habitual tea drinking (≥1 serving/week) prevalence among pregnant women was low, at 16%. After adjustment for potential confounding factors (eg, maternal age, educational level, monthly income) tea drinking during early pregnancy was not associated with an increased risk of preterm birth or abnormal fetal growth (small or large for gestational age) (P>.05). CONCLUSIONS: We did not identify a consistent association between frequency of tea consumption or tea strength and adverse birth outcomes among Chinese pregnant women with low tea consumption. Our findings suggest that occasional tea drinking during pregnancy is not associated with increased risk of preterm birth or abnormal fetal growth. Given the high overall number of annual births in China, our findings have important public health significance.


Asunto(s)
Renta , Edad Materna , Nacimiento Prematuro/epidemiología , , Adulto , China , Estudios de Cohortes , Escolaridad , Femenino , Macrosomía Fetal/epidemiología , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Embarazo , Complicaciones del Embarazo/epidemiología , Primer Trimestre del Embarazo , Encuestas y Cuestionarios
3.
Zhongguo Zhong Yao Za Zhi ; 41(19): 3528-3536, 2016 Oct.
Artículo en Chino | MEDLINE | ID: mdl-28925144

RESUMEN

In order to provide theoretical basis for the rapid identification of mineral traditional Chinese medicines(TCM) with near infrared (NIR)diffuse reflectance spectroscopy, Characteristic NIR spectra of 51 kinds of mineral TCMs were generalized and compared on the basis of the previous research, and the characteristic spectral bands were determined and analyzed by referring to mineralogical and geological literatures. It turned out that the NIR features of mineral TCMs were mainly at 8 000-4 000 cm ⁻¹ wavebands, which can be assigned as the absorption of water, -OH and[CO3 ²â»] and so on. Absorption peaks of water has regularity as follows, the structure water and -OH had a combined peak which was strong and keen-edged around 7 000 cm ⁻¹, the crystal water had two strong peak around 7 000 cm ⁻¹ and 5 100 cm ⁻¹, and water only has a broad peak around 5 100 cm ⁻¹. Due to the differences in the crystal form and the contents of water in mineral TCMs, NIR features of water in mineral TCMs which could be used for identification were different. Mineral TCMs containing sulfate are rich in crystal water, mineral TCMs containing silicate generally had structure water, and mineral TCMs containing carbonate merely had a little of water, so it was reasonable for the use of NIR spectroscopy to classify mineral TCMs with anionic type. In addition, because of the differences in cationic type, impurities, crystal form and crystallinity, mineral TCMs have exclusive NIR features at 4 600-4 000 cm ⁻¹, which can be assigned as Al-OH, Mg-OH, Fe-OH, Si-OH,[CO3 ²â»] and so on. Calcined mineral TCMs are often associated with water and main composition changes, also changes of the NIR features, which could be used for the monitoring of the processing, and to provide references for the quality control of mineral TCMs. The adaptability and limitation of NIR analysis for mineral TCMs were also discussed:the majority of mineral TCMs had noteworthy NIR features which could be used for the NIR analysis. And the NIR features of a few mineral TCMs were inapparent, such as Fluoritum, Realgar and Cinnabar, for which the Raman spectroscopy can be adopted alternatively.


Asunto(s)
Medicina Tradicional China/normas , Minerales/análisis , Espectroscopía Infrarroja Corta , Carbonatos/análisis , Silicatos/análisis , Espectrometría Raman
4.
Zhongguo Zhong Yao Za Zhi ; 40(18): 3560-6, 2015 Sep.
Artículo en Chino | MEDLINE | ID: mdl-26983200

RESUMEN

The aim of this paper is to clarify the mineral origin of traditional Chinese medicine (TCM) Yangqishi and Yinqishi and guide identification of the both, by X-ray diffraction (XRD) Fourier patterns. Morphological identification and conventional physical and chemical analysis wee used to identify 22 batches of Yangqishi and Yinqishi. It used XRD Fourier patterns which has been collected from sample powders to analyze phase composition. It has been found experimentally that the mineral origin of Yinqishi is Talc schist and the mineral origin of Yangqishi is tremolite and actinolite. The results also showed that the method using XRD can get not only an accurate but also rapid identification of Yangqishi and Yinqishi. There are many differences in medicinal properties, efficacy, indications and composition of Yangqishi and Yinqishi, so be careful not to mix them up.


Asunto(s)
Medicamentos Herbarios Chinos/química , Asbestos Anfíboles/química , Difracción de Rayos X
5.
Zhongguo Zhong Yao Za Zhi ; 40(18): 3608-15, 2015 Sep.
Artículo en Chino | MEDLINE | ID: mdl-26983209

RESUMEN

The aim of this paper is to apply Raman spectroscopy technique to develop rapid quantitative models for five kinds of Traditional Chinese Medicine containing CaCO3. In the experiment, Raman spectras of 67 batch of sample including Otolithum Sciaenae, Galaxeae Os, Ophicalcitum, Calcite, Stalactite and their mixture which had different content of CaCO3 were collected, and the quantitative models were established by using an improved siPLS to optimize the characteristic spectral bands and using the CaCO3 contents which were measured by EDTA titration method as references. Compared with the results by EDTA titration, the established quantitative model for CaCO, content showed a prediction result that the average relative deviation of the prediction results is 2. 71% and the average recovery rate was 100.46%, when the content is between 0.465 4-0.999 7, and when the characteristic spectral bands of 1 290-1 280, 730-714, 700-690, 660-650, 465-460, 455-445, 405-385 cm(-1) had been optimized. The result also showed that the model using Raman spectroscopy and based on an improved siPLS can get a rapid determination for contents of 5 kinds of Traditional Chinese Medicine containing CaCO3.


Asunto(s)
Carbonato de Calcio/química , Medicamentos Herbarios Chinos/química , Plantas Medicinales/química , Espectrometría Raman/métodos , Análisis de los Mínimos Cuadrados , Modelos Estadísticos
6.
Zhongguo Zhong Yao Za Zhi ; 39(2): 267-72, 2014 Jan.
Artículo en Chino | MEDLINE | ID: mdl-24761644

RESUMEN

The aim of this paper is to apply near infrared spectroscopy techniques to construct a rapid identification method for 8 kinds of mineral Chinese Medicines containing carbonates. The qualitative model using clustering analysis method in OPUS software can identify accurately 8 kinds of carbonate-containing mineral Chinese medicines. The near-infrared quantitative model was established by using partial least squares method (PLS) for 7 mineral Chinese Medicines in which main component is calcium carbonate. Compared with the results by EDTA titration, the established quantitative analysis model for calcium carbonate content showed a good prediction result that when the content is between 47.61% -99.17%, the average relative deviation of the prediction result is 0.24% and the average recovery rate was 100.3%. The results also showed that the model using near infrared spectroscopy can get not only a rapid identification of the 8 mineral Chinese medicines containing carbonates, but also an accurate and reliabe content determination of calcium carbonate for the 7 mineral Chinese medicines which contain the component.


Asunto(s)
Carbonatos/análisis , Medicina Tradicional China , Minerales/química , Espectrofotometría Infrarroja/métodos , Programas Informáticos , Factores de Tiempo
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