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A convenient and efficient method for the synthesis of various symmetrical and non-symmetrical trans-stilbene derivatives from benzylic halides in the absence of any transition metals is described. Sodium sulfinates played an important role in this transformation. Various functional groups were well tolerated under the optimized reaction conditions.

An efficient method was developed for the desulfitative arylation of indoles with sodium sulfinates using palladium as catalyst and copper chloride dihydrate as oxidant. The direct arylation occurred exclusively in the C-2 position of indoles and proceeded well for a range of different substrates.

A highly selective palladium bis(acetoacetonate)/copper(I) chloride [Pd(acac)2/CuCl] catalytic system for the preparation of dibenzopyranones has been developed. Tandem decarboxylative coupling and lactonization can be realized in one pot using commercially available starting materials. The reaction proceeded well for a range of different substrates.

A highly selective phosphine-based ruthenium catalyst system efficiently catalyzes the direct amination of alcohols with aliphatic tertiary amines, yielding unsymmetric tertiary amines in yields up to 87%. Ligand and solvent both affect the reaction yields significantly. The reaction can be performed with a wide variety of functionalities.

A Pd-catalyzed desulfitative Heck-type reaction of aromatic sulfinic acid sodium salts with various olefins is developed with O(2) as the terminal oxidant under mild conditions. The presence of phosphane ligand DPEphos in anisole can significantly enhance the reaction selectivity.

To evaluate the sleep architecture and hypoxia and clinical features of habitual snoring children with an obstructive sleep apnea-hypopnea index (OAHI) 1 to 5.The polysomnographic data of 267 children aged from 2 to 16 years with habitual snoring were analyzed retrospectively, and the clinical features were analyzed in 108 of the children. The recruited children were divided into primary snoring group (PS group, OAHI≤1), obstructive sleep apnea hypopnea syndrome (OSAHS) group (1OAHI≤5 and obstructive apnea index≤1), lowest oxygen saturation (LSpO2≤0.92) and OSAHS group (OAHI5 or dostructive apnea index1, LSpO20.92).The oxygen desaturation index of the intermediate OSAHS group (3.8±0.4) was significantly higher than that of PS group (1.6±0.1) (χ2=34.5, P0.01). The LSpO2 of intermediate OSAHS group was significantly lower than that of PS group (89(87,91) vs. 93(91,94), χ2=40.2, P0.01). Comparing to the PS group, the non-rapid eye movement 1 ratio (N1%) was significantly higher (19.0±1.2 vs. 14.2±0.1, χ2=14.1, P0.01), and the non-rapid eye movement 3 ratio (N3%) was significantly lower (24.4±1.0 vs. 29.0±1.1, P0.01) in the intermediate OSAHS group. The pediatric questionnaire score intermediate OSAHS group was higher than PS (0.41±0.19 vs. 0.28±0.14, χ2=8.52, P=0.01). The adenoids-nasopharynx ratio was higher than that of PS group (0.70±0.07 vs. 0.62±0.10, χ2=8.96, P=0.01). The hypertrophy of tonsil was higher than PS group (2(1,2) vs. 1(1,2), χ2=7.95, P0.05).Hypoxia and abnormal sleep structure are present in HS children with an OAHI of 1 to 5, and they also have the clinical features of OSAHS.

To explore the efficacies of continuous positive airway pressure (CPAP) for mixed sleep apnea (MSA) events in patients with sleep apnea.A total of 21 patients with sleep apnea whose MSA events10 events/h on overnight polysomnography (PSG) were studied. They were selected from the Sleep Center, Guangzhou Institute of Respiratory Disease. Ten of them were diagnosed only by conventional polysomnography (PSG group) while the diagnosis of another 11 patients was further confirmed by diaphragm electromyogram (EMG) (EMG group). All of them were treated by CPAP titrated manually on PSG.Manual CPAP titrating pressure in PSG group was (8.1 ± 2.2) cmH2O (1 cmH2O = 0.098 kPa) and it was similar to that in EMG group ((8.9 ± 1.5) cmH2O). Apnea-hypopnea index (AHI) decreased significantly after CPAP in both PSG group (6.9 (3.5, 10.2) vs 62.2 (54.7, 71.4) events/h) and EMG group (1.5 (0.5, 5.5) vs 71.3 (59.5, 79.5) events/h) (both P0.01). CPAP could eliminate MSA diagnosed either by conventional PSG (0.1 (0.0, 0.4) vs 29.6 (19.6, 32.4) events/h) or by diaphragm EMG (0.0 (0.0, 0.2) vs 18.1 (9.1, 19.3) events/h) (both P0.01).CPAP can effectively treat MSA events in patients with sleep apnea.

Although the number of studies on allergic diseases in the general population of southern China is increasing, only a few have addressed food allergy (FA) in children in this region. The present study aimed to investigate the prevalence, clinical manifestations, spectrum of allergens, and related risk factors of FA in preschool children in Guangdong Province, southern China.A random cluster-sampling method was used to select 24 kindergartens from 12 cities in Guangdong Province. The parents or guardians of the children were requested to complete a questionnaire on general information and data regarding FA diagnosis and symptoms in the children and their first-degree relatives. Thereafter, the Chi-square test, multivariate regression analysis, and Spearman's rank-order correlation coefficient analysis were performed to identify statistically significant differences.Analysis of 2540 valid questionnaires revealed an FA prevalence rate of 4%. Adverse food reactions were due to the consumption of shrimp (4.4%), crab (3.2%), mango (2.3%), cow's milk and dairy products (1.9%), and eggs (1.4%). Logistic regression analysis indicated that a history of FA and a history of allergic rhinitis in the first-degree relatives were the major factors leading to FA in children.The incidence of FA in children in Guangdong Province is higher than that commonly believed. An individual's genetic background is an important risk factor for FA. Hence, mitigation of the impact of lifestyle and environmental factors should be carefully considered to reduce the incidence of childhood FA.

Under optimized transition metal free conditions, benzylic chlorides and bromides are transformed to the stilbenes under air.

The optimized conditions allow the use of various sodium sulfinates as aryl source in C—C bond formation with α,β-unsaturated ketones and aldehydes.

An efficient method was developed for the desulfitative arylation of indoles with sodium sulfinates using palladium as catalyst and copper chloride dihydrate as oxidant. The direct arylation occurred exclusively in the C-2 position of indoles and proceeded well for a range of different substrates.

A highly selective palladium bis(acetoacetonate)/copper(I) chloride [Pd(acac)2/CuCl] catalytic system for the preparation of dibenzopyranones has been developed. Tandem decarboxylative coupling and lactonization can be realized in one pot using commercially available starting materials. The reaction proceeded well for a range of different substrates.

A highly selective phosphine-based ruthenium catalyst system efficiently catalyzes the direct amination of alcohols with aliphatic tertiary amines, yielding unsymmetric tertiary amines in yields up to 87%. Ligand and solvent both affect the reaction yields significantly. The reaction can be performed with a wide variety of functionalities.

A Pd-catalyzed desulfitative Heck-type reaction of aromatic sulfinic acid sodium salts with various olefins is developed with O2 as the terminal oxidant under mild conditions. The presence of phosphane ligand DPEphos in anisole can significantly enhance the reaction selectivity.