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1.
Environ Res ; 197: 111071, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33798515

RESUMEN

Anxiety, a common and devastating mental disorder, has raised widespread interests. The impacts of air pollution on physical health are well known, whereas few studies have explored the association of atmospheric pollution, especially short-term air pollution exposure, with the risk of anxiety disorders. In addition, there are increasing concerns in emerging evidence supporting a possible etiological link. Therefore, our aim was to evaluate the relationship between short-term exposure to atmospheric pollutants and anxiety outpatient visits in Xi'an, a city of northwestern China and a metropolis with relatively heavy air pollution. We collected the data of both daily outpatient visits and daily air pollution (SO2, NO2, and PM10) between January 1, 2010 and January 31, 2016 (2222 days). To clarify the association between short-term ambient atmospheric pollution exposure and anxiety outpatient visits, an over-dispersed Poisson generalized additive model was applied by adjusting the day of the week and weather conditions (including temperature, humidity, sunlight hours, and rainfalls). Positive association between gaseous air pollutants (SO2 and NO2) and anxiety daily outpatient visits was observed. Moreover, the largest estimated values of both SO2 and NO2 were evidence at lag 03 (4-day moving average lag), with 10 µg/m3 increase corresponded to the increase of outpatient anxiety visits at 4.11% (95% CI: 2.15%, 6.06%) for SO2 and 3.97% (95% CI: 1.90%, 6.06%) for NO2. However, there was no differences in susceptibility to air pollutants between different genders as well as different ages. Taken together, short-term exposure to ambient air pollutants, especially gaseous air pollutants (NO2 and SO2), can be related to higher risk of anxiety outpatient visits.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Ansiedad/inducido químicamente , Ansiedad/epidemiología , Trastornos de Ansiedad , China/epidemiología , Ciudades , Femenino , Hospitales , Humanos , Masculino , Pacientes Ambulatorios , Material Particulado/análisis
2.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 1): o63, 2009 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-21580165

RESUMEN

In the title compound, C(36)H(28)O(5), the terminal benzene rings are twisted at dihedral angles of 6.75 (12), 70.86 (14) and 82.02 (12)° with the respect to the central plana r[maximum deviation = 0.070 (3) Å] chromen-4-one ring system. In the crystal structure, π-π stacking is observed between parallel benzene rings of adjacent mol-ecules [centroid-centroid distance = 3.7459 (16) Å].

3.
Transl Cancer Res ; 8(4): 1647-1652, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35116910

RESUMEN

Tumor lysis syndrome (TLS) is an oncologic emergency that usually occurs after initial treatment of a malignant tumor. It manifests as hyperuricaemia, hyperkalaemia, hyperphosphataemia and hypocalcaemia, ultimately resulting in acute kidney failure, seizures, cardiac arrhythmias, and even death. Here, we report a very rare case of spontaneous TLS in a patient with advanced gastric adenocarcinoma who eventually succumbed to renal failure. Extra vigilance towards electrolyte imbalances should be given during initiation of therapy in cases of large gastric cancer with severe distant metastasis. Risk assessment prior to surgery, early diagnosis and comprehensive treatment strategies are vital in improving the prognosis of gastric cancer patients with TLS. Urgent hemodialysis should be implemented as soon as possible in order to prevent further renal deterioration.

4.
Sci Rep ; 6: 19146, 2016 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-26751844

RESUMEN

Reproductive isolation (RI) plays an important role for speciation, but assessing reproductive barriers at all life-cycle stages remains challenging. In plants, most studies addressing the topic have been focusing on herbs with short generation times. The present study attempted to quantify several reproductive barriers between a hybridizing species pair of long-lived woody rhododendrons. Consistent with findings of previous studies, pre-zygotic reproductive barriers contributed more to total RI than post-zygotic reproductive barriers. Especially in the more widespread species geographic isolation was an important barrier, and pollinator constancy contributed exceptionally to RI in both species. Additionally to strong pre-zygotic reproductive barriers, post-zygotic reproductive barriers were considerable, and had asymmetric tendencies favoring one of the species as maternal parent. Overall, despite occasional hybridization, the present study provides evidence for strong RI between R. cyanocarpum and R. delavayi.


Asunto(s)
Hibridación Genética , Aislamiento Reproductivo , Rhododendron , Polinización , Reproducción , Rhododendron/química , Rhododendron/genética , Suelo/química
5.
Bot Stud ; 55(1): 36, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28510962

RESUMEN

BACKGROUND: Rhododendron is one of the most well-known alpine flowers. In order to identify performances relating to Rhododendron's natural habitats we investigated the leaf anatomical structures and photosynthetic characteristics of R. yunnanense, R. irroratum and R. delavayi, which showed different responses after being transplanted into a common environment. RESULTS: When compared with R. irroratum and R. delavayi, R. yunnanense had lower leaf dry mass per unit area (LMA) and larger stomata, but smaller stomatal density (SD) and total stomata apparatus area percent (At), lower stomatal conductance (Gs), transpiration rate (Tr), light compensation point (LCP), light saturation point (LSP), light-saturated photosynthetic rate (Amax) and leaf nitrogen content per unit area (Na). LMA was positively correlated with Amax and maximum rates of carboxylation (Vcmax). However, leaf N content was not significantly correlated with Amax. Thus, the variation in leaf photosynthesis among species was regulated largely by changes in LMA, rather than the concent of nitrogen in leaf tissue. CONCLUSIONS: R. yunnanense plants are vulnerable to moisture and light stress, while R. irroratum and R. delavayi are better suited to dry and high radiation environments. The present results contribute to our understanding physiological trait divergence in Rhododendron, as well benefit introduction and domestication efforts for the three species of Rhododendron studied in this work.

6.
Org Lett ; 16(19): 5004-7, 2014 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-25221862

RESUMEN

A novel synthetic approach to construct various 3,6-anhydrohexosides via an intramolecular cyclization of corresponding triflates is described. The nucleophilic attack from C3 p-methoxybenzylated hydroxyl to C6 trifluoromethanesulfonate on triflate structures triggered the cyclization reaction to provide 3,6-anhydrohexosides in excellent yields, making the strategy more efficient with respect to the reported protocols. By applying this methodology, a concise first total synthesis of natural product isolated from leaves of Sauropus rostratus was accomplished.


Asunto(s)
Productos Biológicos/síntesis química , Glicósidos/síntesis química , Phyllanthus/química , Productos Biológicos/química , Catálisis , Técnicas Químicas Combinatorias , Cristalografía por Rayos X , Ciclización , Glicósidos/química , Conformación Molecular , Estructura Molecular , Hojas de la Planta/química , Estereoisomerismo
7.
Chin J Nat Med ; 11(6): 676-83, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24345510

RESUMEN

Neokotalanol, a potent α-glucosidase inhibitor isolated from Salacia reticulata, was synthesized through a key coupling reaction between a perbenzylated thiosugar and an appropriately protected perseitol triflate derived from D-mannose. This key step was found to be quite temperature dependent, and a simultaneous cyclization of the triflate leading to a characteristic 2,4,7-trioxabicyclo[4.2.1]nonane system was detected.


Asunto(s)
Inhibidores Enzimáticos/síntesis química , Inhibidores de Glicósido Hidrolasas , Extractos Vegetales/síntesis química , Salacia/química , Inhibidores Enzimáticos/química , Extractos Vegetales/química
8.
Chin J Nat Med ; 11(5): 538-45, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24359781

RESUMEN

AIM: In a search for new cardiovascular drug candidates, a series of novel oxime ethers derived from a natural isochroman-4-one were synthesized. METHOD: Compounds 3 and 6, derived from the natural antihypertensive compound 7, 8-dihydroxy-3-methyl-isochroman-4-one (XJP), were designed and synthesized. Subsequently, a series of novel isochroman-4-one oxime ether hybrids were prepared by hybridizing various N-substituted isopropanolamine functionalities to isochroman-4-one oxime. Furthermore, ß1-adrenergic blocking activities of the synthesized compounds were assayed using the isolated rat left atria. RESULTS: Twenty target compounds were obtained, and the preliminary structure-activity relationships were deduced. The most promising compound Ic exhibited ß1-adrenoceptor blocking activity (inhibition: 52.2%) at 10(-7) mol·L(-1), which was superior to that of propranolol (inhibition: 49.7%). CONCLUSION: The results suggested that natural product XJP/isopropanolamine moiety hybrids may provide a promising approach for the discovery of novel cardiovascular drug candidates.


Asunto(s)
Antagonistas Adrenérgicos beta/síntesis química , Antagonistas Adrenérgicos beta/farmacología , Benzopiranos/síntesis química , Benzopiranos/farmacología , Medicamentos Herbarios Chinos/síntesis química , Medicamentos Herbarios Chinos/farmacología , Hipertensión/tratamiento farmacológico , Oximas/química , Antagonistas Adrenérgicos beta/química , Animales , Antihipertensivos/síntesis química , Antihipertensivos/química , Antihipertensivos/farmacología , Benzopiranos/química , Medicamentos Herbarios Chinos/química , Humanos , Hipertensión/fisiopatología , Masculino , Estructura Molecular , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
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