Physical activity, sedentary behavior, and the risk of functional gastrointestinal disorders: A two-sample Mendelian randomization study.

OBJECTIVES: Functional dyspepsia (FD) and irritable bowel syndrome (IBS) are prevalent functional gastrointestinal disorders (FGIDs). In this study we aimed to explore the causal association between physical activity or sedentary behavior and the risk of FD and IBS. METHODS: Mendelian randomization (MR) analysis was employed. Candidate genetic instruments for physical activity and sedentary behavior were retrieved from the latest published Genome-Wide Association Study (GWAS), which included up to 703 901 participants. Summary-level GWAS data for FD (8 875 cases and 320 387 controls) and IBS (9 323 cases and 301 931 controls) were obtained from the FinnGen study. The causal effects were mainly estimated by inverse variance weighted (IVW) method. Sensitivity analyses were implemented with Cochran's Q test, MR-Egger intercept test, leave-one-out analysis, and the funnel plot. RESULTS: No significant association of moderate-to-vigorous intensity physical activity (MVPA), leisure screen time (LST), sedentary behavior at work (SDW), and sedentary commuting (SDC) with the risk of FD was found. However, there was a suggestive correlation between MVPA and the decreased risk of FD (odds ratio [OR] 0.63, 95% confidence interval [CI] 0.39-0.99, P = 0.047). Genetically predicted MVPA decreased the risk of IBS (OR 0.58, 95% CI 0.40-0.84, P = 0.004), while increased LST was positively associated with IBS risk (OR 1.33, 95% CI 1.15-1.53, P < 0.001). No causal effects of SDW or SDC on IBS risk were observed. CONCLUSION: MVPA and LST are causally linked to the development of IBS, which will facilitate primary prevention of IBS.

Enantioselective Total Synthesis of (-)-Daphenylline.

A concise enantioselective total synthesis of (-)-daphenylline, a hexacyclic Daphniphyllum alkaloid with a unique benzene ring, was achieved in 14 steps. The synthesis commences with two chiral stereocenters, C2 and C18, readily installed via Carreira's Ir/amine dual-catalyzed allylation. The allylic bridgehead amine 6 was rapidly prepared through Wickens' photoredox-catalyzed hydrocarboxylation of olefin and CuBr2-catalyzed α-amination of ketone. The tetracycle 4 was formed via Pd-catalyzed reductive Heck reaction or, more concisely, by Krische's Rh-catalyzed reductive 1,6-enyne cyclization. In this synthesis, newly reported Wickens' photoredox-catalyzed hydrocarboxylation was used twice, and Friedel-Crafts acylation thrice.

Chemical constituents with inhibition against TNF-α from Merrillanthus hainanensis.

Two new steroidal glycosides oxystauntoside A (1) and oxystauntoside B (2), together with sixteen known compounds (3-18) were isolated from the 95% ethanol extract of Merrillanthus hainanensis. Their structures were characterized by extensive spectroscopic analysis including NMR and mass spectra and single crystal X-ray crystallography. The absolute configuration of 1 and 2 were further determined by ECD calculations. All of these compounds were isolated from M. hainanensis for the first time. All the fractions and compounds were tested for the anti-inflammatory activity against the TNF-α factor. The ethyl acetate fraction showed the most potent inhibition (71.3%) at 10 µg/mL and compounds 5 (78.9%) and 9 (73.4%) in this fraction with both carboxyl and phenolic hydroxyl groups showed significant inhibition at 10 µM. Our study provided the first scientific report for the medicinal value of M. hainanensis.

Serum N-glycan markers for diagnosing liver fibrosis induced by hepatitis B virus.

BACKGROUND: Hepatitis B virus (HBV) infection is the primary cause of hepatitis with chronic HBV infection, which may develop into liver fibrosis, cirrhosis and hepatocellular carcinoma. Detection of early-stage fibrosis related to HBV infection is of great clinical significance to block the progression of liver lesion. Direct liver biopsy is regarded as the gold standard to detect and assess fibrosis; however, this method is invasive and prone to clinical sampling error. In order to address these issues, we attempted to find more convenient and effective serum markers for detecting HBV-induced early-stage liver fibrosis. AIM: To investigate serum N-glycan profiling related to HBV-induced liver fibrosis and verify multiparameter diagnostic models related to serum N-glycan changes. METHODS: N-glycan profiles from the sera of 432 HBV-infected patients with liver fibrosis were analyzed. Significant changed N-glycan levels (peaks) (P < 0.05) in different fibrosis stages were selected in the modeling group, and multiparameter diagnostic models were established based on changed N-glycan levels by logistic regression analysis. The receiver operating characteristic (ROC) curve analysis was performed to evaluate diagnostic efficacy of N-glycans models. These models were then compared with the aspartate aminotransferase to platelet ratio index (APRI) , fibrosis index based on the four factors (FIB-4), glutamyltranspeptidase platelet albumin index (S index), GlycoCirrho-test, and GlycoFibro-test. Furthermore, we combined multiparameter diagnostic models with alanine aminotransferase (ALT) and platelet (PLT) tests and compared their diagnostic power. In addition, the diagnostic accuracy of N-glycan models was also verified in the validation group of patients. RESULTS: Multiparameter diagnostic models constructed based on N-glycan peak 1, 3, 4 and 8 could distinguish between different stages of liver fibrosis. The area under ROC curves (AUROCs) of Model A and Model B were 0.890 and 0.752, respectively differentiating fibrosis F0-F1 from F2-F4, and F0-F2 from F3-F4, and surpassing other serum panels. However, AUROC (0.747) in Model C used for the diagnosis of F4 from F0-F3 was lower than AUROC (0.795) in FIB-4. In combination with ALT and PLT, the multiparameter models showed better diagnostic power (AUROC = 0.912, 0.829, 0.885, respectively) when compared with other models. In the validation group, the AUROCs of the three combined models (0.929, 0.858, and 0.867, respectively) were still satisfactory. We also applied the combined models to distinguish adjacent fibrosis stages of 432 patients (F0-F1/F2/F3/F4), and the AUROCs were 0.917, 0.720 and 0.785. CONCLUSION: Multiparameter models based on serum N-glycans are effective supplementary markers to distinguish between adjacent fibrosis stages of patients caused by HBV, especially in combination with ALT and PLT.

Hyperlactatemia Predicts Citrate Intolerance With Regional Citrate Anticoagulation During Continuous Renal Replacement Therapy.

PURPOSE:: We aim to determine whether hyperlactatemia, which suggests multi-organ dysfunction and impaired organic substrate metabolism, may predict intolerance to regional citrate anticoagulation (RCA) during continuous venovenous hemofiltration (CVVH). METHODS:: We performed a single-center, retrospective observational study in critically ill patients with acute kidney injury or end-stage renal disease and evaluated the association of peak serum lactate levels with citrate intolerance (CI) during the initial 72 hours of RCA-CVVH, defined by serum total-to-ionized calcium >2.5 plus systemic hypocalcemia. RESULTS:: Eighty-eight patients were studied (aged 59 ± 14 years, 66% males, Acute Physiology and Chronic Health Evaluation II: 31 ± 8). Citrate was dosed at median 2.1 mmol/L of blood flow, with citrate load of 30 mmol/h, and CVVH effluent of 43 mL/kg/h. Twenty patients developed CI. Comparing patients with CI versus none, peak lactate levels were 8 (5-11) versus 3 (2-6) mmol/L, calcium replacement was 13 (10-17) versus 11 (8-12) mmol/h, and standard base excess was -4 (-12 to 1) versus 2(-4 to 7) mmol/L, respectively ( P < .05). Citrate intolerance developed in 38%, 44%, and 55%, in patients with peak lactate >4, >6, >7 mmol/L, respectively, versus 7% in those with peak lactate ≤4 mmol/L ( P ≤ .001), despite comparable citrate load and effluent rates across all categories. On multivariate analysis, hyperlactatemia and hyperbilirubinemia predicted CI ( P ≤ .01), which was associated with increasing calcium infusion requirement. Higher peak lactate from >4 to >7 mmol/L predicted CI with graded increase in odds ratio and specificity from 59% to 87%, but the corresponding negative predictive value from 93% to 87%. Area under nonparametric receiver operating characteristic curve for peak lactate and CI was 0.78. CONCLUSION:: Hyperlactatemia predicts CI during RCA-CVVH with reasonable discriminatory performance in critically ill patients. Serum lactate surveillance may help preempt issues with citrate toxicity.

A rumor spreading model based on information entropy.

Rumor spreading can have a significant impact on people's lives, distorting scientific facts and influencing political opinions. With technologies that have democratized the production and reproduction of information, the rate at which misinformation can spread has increased significantly, leading many to describe contemporary times as a 'post-truth era'. Research into rumor spreading has primarily been based on either model of social and biological contagion, or upon models of opinion dynamics. Here we present a comprehensive model that is based on information entropy, which allows for the incorporation of considerations like the role of memory, conformity effects, differences in the subjective propensity to produce distortions, and variations in the degree of trust that people place in each other. Variations in the degree of trust are controlled by a confidence factor ß, while the propensity to produce distortions is controlled by a conservation factor K. Simulations were performed using a Barabási-Albert (BA) scale-free network seeded with a single piece of information. The influence of ß and K upon the temporal evolution of the system was subsequently analyzed regarding average information entropy, opinion fragmentation, and the range of rumor spread. These results can aid in decision-making to limit the spread of rumors.

Single-Drop Raman Imaging Exposes the Trace Contaminants in Milk.

Better milk safety control can offer important means to promote public health. However, few technologies can detect different types of contaminants in milk simultaneously. In this regard, the present work proposes a single-drop Raman imaging (SDRI) strategy for semiquantitation of multiple hazardous factors in milk solutions. By developing SDRI strategy that incorporates the coffee-ring effect (a natural phenomenon often presents in a condensed circle pattern after a drop evaporated) for sample pretreatment and discrete wavelet transform for spectra processing, the method serves well to expose typical hazardous molecular species in milk products, such as melamine, sodium thiocyanate and lincomycin hydrochloride, with little sample preparation. The detection sensitivity for melamine, sodium thiocyanate, and lincomycin hydrochloride are 0.1 mg kg-1, 1 mg kg-1, and 0.1 mg kg-1, respectively. Theoretically, we establish that the SDRI represents a novel and environment-friendly method that screens the milk safety efficiently, which could be well extended to inspection of other food safety.

A Paradoxical Evolutionary Mechanism in Stochastically Switching Environments.

Organisms with environmental sensors that guide survival are considered more likely to be favored by natural selection if they possess more accurate sensors. In this paper, we develop a theoretical model which shows that under certain conditions of environmental stochasticity, selection actually favors sensors of lower accuracy. An analogy between this counter-intuitive phenomenon and the well-known Parrondo's paradox is suggested.

[Reasons of multiple operations in children with airway foreign body].

OBJECTIVE: To explore the reasons of multiple operations in children with airway foreign body through analyzing the clinical data of children who received two or more operations. METHODS: From 2003 to 2009, all children with airway foreign body who received two or more operations in hospital were enrolled. The clinical manifestations, image before and after operation and intraoperative conditions were retrospectively analyzed, in order to find the reasons of multiple operations. RESULTS: All children fully recovered, no serious complications or death. The reasons of two or more operations were multiple: 21 cases (42.8%) were related to the factor of apparatus, 20 (40.8%) cases were related to the quality, surrounding conditions and location of the foreign body and experience and surgical skills of operator, 4 (8.2%) cases were due to incarceration of foreign body, another 4 (8.2%) cases were due to unstable intraoperative oxygen saturation. CONCLUSIONS: Both subjective and objective factors (quality, surrounding conditions or location of foreign body, et al) were related to multiple operations. To reduce the chance of multiple operations, careful preoperative assessment and preparation are necessary.

[Correlation between serum uric acid levels and obstructive sleep apnea/hypopnea syndrome in children].

OBJECTIVE: To explore the level of serum uric acid (UA) in children with obstructive sleep apnea/hypopnea syndrome (OSAHS). METHOD: Between Sep. 2008 and Mar. 2010, 138 children with OSAHS were enrolled in study group. Sixty-five children with accessory auricle or ptosis of upper lid were enrolled into the control group. Furthermore, according to apnea/hypopnea index (AHI) or obstructive apnea index (OAI) the study group was further divided into three subgroups (mild, moderate and severe group). At last, the study group and control group were divided into two groups according to the body mass index (BMI), separately. The fasting serum UA level was compared among the different groups. Then the correlation between the serum UA level and AHI, BMI, oxygen desaturation index, least arterial oxygen saturation (LSaO(2)) and the percentage of total sleep time with arterial oxygen saturation < 0.92 was also analyzed in OSAHS children with or without overweight and obesity respectively. RESULT: The difference of serum UA level between the study group and control group (z = -0.443), and the difference among the three groups (χ(2) = 1.241) was not significant(P > 0.05). The serum UA level in overweight and obese children [study group, 273.0 (238.3 - 357.3); control group, 298.0 (253.0 - 336.0)] was significantly higher than that in children with normal BMI [study group, 246.5(215.8 - 300.0); control group, 266.0 (224.0 - 303.3)] (z = -2.084, -2.214, P < 0.05). That serum UA level did not correlate with the above index of OSAHS was observed in children with or without overweight and obesity in study group (P > 0.05). CONCLUSION: Findings of higher serum UA level were not observed in children with OSAHS. There was no correlation between serum UA level and the above indices of OSAHS. The serum UA level in overweight and obese children was significantly higher than that in children with normal BMI.

[Diagnostic role of pulse transit time in children with sleep disordered breathing].

OBJECTIVE: To explore the diagnostic value of pulse transit time (PTT) in children with sleep disordered breathing(SDB). METHODS: Forty eight randomly selected snorers (2 - 13 years) with SDB were examined by PSG and PTT in the same time. Data obtained were analyzed by different technicians respectively. Statistics and analysis of the data were performed. RESULTS: Apnea hypopnea index (AHI), obstructive apnea index (OAI), the lowest oxygen and micro-arousal index were obtained by PSG and PTT. The results was described as M [25 percentile; 75 percentile]: 4.9[1.3;10.1], 4.6[1.5;11.8]; 1.2[0.7;4.9], 1.3[0.6;5.0]; 0.93[0.85;0.95], 0.93[0.84;0.95]; 14.5[12.6;16.4], 26.0[17.4;30.6]. The difference of AHI, OAI, and the lowest oxygen were not significant (P > 0.05), while the PTT arousal index detection rate was higher than PSG (Z = -5.19, P < 0.01). There was no significant difference in the diagnosis of obstructive sleep apnea-hypopnea syndrome (OSAHS) and determination of degree of patient's condition (P > 0.05). PTT could identify upper airway resistance syndrome in children without OASHS. CONCLUSIONS: Both methods can be used to diagnose SDB. However, PTT is easy to use and suitable for the diagnosis of SDB in children, especially for UARS.

[A preliminary study of the secondary postoperative haemorrhage in pediatric coblation adenotonsillectomy].

OBJECTIVE: To compare secondary postoperative haemorrhage rate of coblation with the conventional pediatric adenotonsillectomy. And to analyze possible reasons which cause the secondary bleeding after coblation adenotonsillectomy. METHODS: A retrospective study was applied to compare the secondary postoperative haemorrhage rate and the bleeding moment between two groups in which 1-14 years old children from April 2005 to September 2009 in Guangzhou Children's Hospital were included. Group A was pediatric patients who had conventional adenoidectomy and/or tonsillectomy (dissection, without heat damage to the tissue) from April 2005 to July 2006 in Department of Otorhinolaryngology. Group B was pediatric patients who had coblation adenoidectomy and/or tonsillectomy from April 2008 to September 2009 in Department of Otorhinolaryngology. RESULTS: Two of 484 cases in group A had secondary postoperative bleeding, the rate was 0.4%. One happened 2 days after operation, another after 3 days. Eleven of 502 cases in group B had secondary postoperative bleeding, the rate was 2.2%. Secondary bleeding happened 2 to 12 days after surgery, median 6.0 days. The secondary postoperative haemorrhage rate of operating by the freshman was 2.6%(10/385), and it was 0.9%(1/117) by the senior. The rate of secondary bleeding was higher in group B than group A (chi(2) = 5.987, P < 0.05). There was no significant difference of secondary bleeding time in both groups (Mann-Whitney U score was 2.500, P > 0.05). Six of 13 cases who had secondary bleeding suffered wound or upper respiratory tract infection. Three of 13 ate inappropriately after the operation. CONCLUSIONS: Pediatric coblation adenotonsillectomy is a new method. The most possible reasons of secondary bleeding are poor surgery skills and ill experience. And, infection, inappropriate eating after the operation may be the other reasons of secondary bleeding.

[Study on periodic limb movement during sleep in children with sleep-disordered breathing].

OBJECTIVE: To explore the correlation between periodic limb movement index (PLMI) and the apnea-hypopnea index (AHI), apnea index (AI), hypopnea index (HI) and lowest oxygen saturation (LSaO2) in sixty-four children with sleep-disordered breathing (SDB). METHODS: Between March 2008 and May 2009, sixty-four children suspected of OSAHS underwent overnight polysomnogram monitoring in our medicine sleep center. OSAHS was diagnosed according to the general criterion. Sixty-four children were divided into two groups. Thirty children were diagnosed as OSAHS and 34 children were diagnosed as primary snoring (PS, 32 children) or upper airway resistance syndrome (UARS, 2 children). The difference of PLMI and periodic limb movement index during sleep associated with arousals (PLMI-arousal) were compared between the two groups. Besides this, the correlation between PLMI, periodic limb movement index during sleep associated with arousals and AHI, AI, HI and LSaO2 were also analyzed in all SDB children. Furthermore, all SDB children were divided into two groups according to PLMI (< 5 events/h vs ≥ 5 events/h). AHI, AI, HI, LSaO2 and sleep structure were compared between the two groups. RESULTS: (1) The difference of PLMI and PLMI-arousal between the children with OSAHS and children with other SDB types (PS and UARS) were not significant (z value, -1.279, -1.490; P value, 0.201, 0.136, respectively). (2) The increased sleep stage I was significant as being compared between the two groups (< 5 events/h vs ≥ 5 events/h, t = -2.16, P < 0.05). However, other sleep stages and sleep efficiency were not significantly different (P value, all > 0.05). (3) The difference of HI, AI, AHI, arousals index (ArI) and LSaO2 were not significant between the two groups (< 5 events/h vs ≥ 5 events/h, P value, all > 0.05). (4) PLMI and PLMI-arousal were not correlated with AHI, HI, AI, AHI and LSaO2 (Spearman rank correlation analysis). CONCLUSIONS: PLMS may be independent of SDB and PLMS had a little influence on sleep structure.

[Clinical analysis of upper airway resistance syndrome and obstructive sleep apnea-hypopnea syndrome in children].

OBJECTIVE: To analyze the similarities and differences of the clinical manifestations between the children with upper airway resistance syndrome (UARS) and obstructive sleep apnea-hypopnea syndrome (OSAHS), and to explore the clinical features and characteristics of sleep respiratory parameters. METHODS: Using the double-blind method, all children were diagnosed as UARS or OSAHS through the polysomnography test and the results of all children were analyzed by a sleep technician and an otolaryngologist. Another ENT doctor recorded their clinical and physical examination in detail. RESULTS: Polysomnography showed that the apnea-hypopnea index (AHI) and the lowest oxygen in 253 children with OSAHS were 3.60[2.00;7.55] times/h and 0.90[0.85;0.91], and were 0.90[0.50;1.10] times/h and 0.95[0.92;0.96] in 102 children with UARS, the difference of the two groups by rank test was statistically significant. The proportion of UARS and OSAHS was more common during preschool period than during school-age period. The chief complaint in two groups was sleep snoring, and the main symptoms were sleep restless, attention deficit/hyperactivity and breath with mouth open. The incidence rate of above symptoms were as follows, 94.1%, 72.5%, 62.7% and 37.3% in children with UARS, 92.9%, 78.7%, 57.7% and 45.5% in children with OSAHS. The difference was not significant by chi-square test (P>0.05). Tonsil and adenoid hypertrophy were also observed in the two groups, the difference was not significant (chi2 = 0.27, P= 0.87). However, the children with OSAHS were more apt to have the sleep apnea than with UARS, the difference was statistically significant (chi2 = 34.07, P<0.001). CONCLUSIONS: The clinical manifestations of two groups are similar, the difference between UARS and OSAHS can not be determined by the patient's clinical performance. Sleep apnea can be more easily observed in children with OSAHS than that in UARS, the final diagnosis is based on polysomnography.

[Comparison of the sleep architecture and symptom of inattention-hyperactivity in children with obstructive sleep apnea hypopnea syndrome before and after surgery].

OBJECTIVE: To observe the symptoms of inattention, hyperactivity among obstructive sleep apnea hypopnea syndrome (OSAHS) children, also to investigate the effects of surgery (tonsillectomy and adenoidectomy or adenoidectomy alone) on the changes of sleep architecture and inattention-hyperactivity score (IHS). METHODS: Between June 2004 and may 2007, eighty children diagnosed as OSAHS with overnight polysomnography (PSG) were included in this study, only sixteen children had complete pre-op and post-op PSG data. Thirty children with vocal cord nodules were selected as control group. DSM-IV-derived IHS was evaluated by neurologist. All OSAHS children accepted surgery (tonsillectomy and adenoidectomy or adenoidectomy alone) and IHS evaluation. The pre-op and post-op sleep architecture and IHS were compared with that of control group. RESULTS: (1) The median IHS 80 OSAHS children was higher than that it in control group (0.89 vs 0.17) and the difference was significant (Z = -4. 276, P < 0.05). After surgery, it showed a significant reduction in IHS (0.44 vs 0.89, t = 6.219, P < 0.05). (2) Twenty-five OSAHS children had pre-op IHS greater than 1.25 and nine had post-op IHS greater than 1.25, while only three children in control group had IHS greater than 1.25. The difference was statistically significant (chi2 = 5.192, 9.56 respectively, P < 0.05). (3) For sixteen OSAHS children who had both pre-op and post-op PSG data, a decrease in the percentage of phase 1 sleep and an increase in the percentage of phase 2 sleep, slow wave sleep (SWS) and rapid eye movement (REM) sleep were observed in six months after surgery and the difference was significant (t = 12.2, -5.4, -6.3, - 8.1 respectively, P < 0.001). After surgery, apnea-hypopnea index (AHI) decreased from 13.9 times/h to 1.5 times/h while lowest saturation of blood oxygen (LSaO2) increased from 0.855 to 0.940 (t = 5.3, - 3.7 respectively, P < 0.01). REM sleep percentage and LSaO2 was still lower than that of control group six months after surgery. CONCLUSIONS: Children with OSAHS showed significantly impaired attention and hyperactivity as compared with control group. Improvement of behavior and sleep architecture were observed after adenoidectomy and tonsillectomy.

[Diagnosis and treatment of obstructive sleep apnea hypopnea syndrome in children with risk factors].

OBJECTIVE: To analyse the clinical features of children with obstructive sleep apnea-hypopnea syndrome (OSAHS), accompanying with risk factors. METHODS: The clinic data of 19 patients treated in the Department of Otorhinolaryngology of Guangzhou Children's Hospital between January 2005 to January 2008 were investigated retrospectively. Among them, 5 were < 2 years old, 6 with craniofacial deformity: small mandible and (or) mandibular retrusion (5 cases), transverse facial cleft (1 case), Down's syndrome (2 cases), cerebral palsy (2 cases), chronic bronchitis (3 cases) and mucopolysaccharidoses (1 case). Nineteen patients with symptoms of snoring, mouth breathing, were diagnosed as OSAHS by polysomnography (PSG) and treated by tonsillectomy and (or) adenoidectomy in hospital. All patients were closely followed-up. RESULTS: Fourteen patients underwent PSG 6 months to 1 year after operation, 11 patients recovered, the median [percentiles 25; percentiles 75] apnea-hypopnea index (AHI) decreased from the pre-operative 22.5 [16.5; 24.3] times/h to 2.0 [1.5; 4.3] times/h, and the lowest oxygen saturation (LSaO(2)) before operation was 0.63, and was higher than 0.92 after operation, 1 case accompanying with chronic bronchitis, the pulmonary hypertension was improved after operation. One case with Down's syndrome was not significantly improved, preoperative AHI and LSaO(2) was 22.4 times/h and 0.67, and after operation was 14.2 and 0.84; 2 cases accepted adenoidectomy only, snoring, mouth breathing reappeared 3 months after operation, pre-operative PSG results showed AHI 24.6 times/h and 26.6 times/h, LSaO(2) was 0.69 and 0.73, after operation the AHI was 10.6 times/h and 8.5 times/h, LSaO(2) was 0.90 and 0.88, the symptoms disappeared after adenotonsillectomy. Five cases did not have PSG because they lived far away in the other cities, their pre-operative PSG showed AHI 16.4 to 26.2 times/h, LSaO(2) was 0.65 to 0.76. One year after operation, these patients were followed-up by telephone, 4 children were significantly improved, 1 case with mandibular symptoms showed no improvement. CONCLUSIONS: For OSAHS children accompanying with risk factors, if they have adenoid and tonsil hypertrophy, adenotonsillectomy is the major treatment. Because of the existence of risk factors, perioperative risk increased, even the failure of operation. so these patients must be comprehensively assessed before operation. Satisfied results can be achieved by close observation after operation and management of complications as soon as possible.

[Arousals in children with obstructive sleep apnea-hypopnea syndrome].

OBJECTIVE: To explore the difference of arousal index between the children with obstructive sleep apnea-hypopnea syndrome (OSAHS) and children with primary snoring. Furthermore, to explore the correlation between the above mentioned arousals and the apnea-hypopnea index (AHI) and lowest oxygen saturation (LSaO(2)). METHODS: Between March 2007 and February 2008, 102 children suspected of OSAHS underwent overnight polysomnogram monitoring in our medicine sleep center. OSAHS was diagnosed according to the general criterion [Draft of guidelines for the diagnosis and treatment of pediatric sleep apnea hypopnea syndrome (Urumqi) which was published in Chin J Otorhinolaryngol Head Neck Surg in February, 2007]. One-hundred and two children were divided into two groups according to the guidelines. Sixty six children [56 boys, 10 girls; aged 4 - 17 years, (7.01 +/- 2.24) years (x(-) +/- s)] who were diagnosed as OSAHS were enrolled in study group and 36 children [29 boys, 7 girls; aged 4 - 13 years, (7.44 +/- 2.68) years] who were diagnosed as primary snoring made up control group. The difference of spontaneous arousal index, total arousal index and arousal index related to respiratory stimuli and limb movement were compared between the two groups. Besides this, the correlation between spontaneous arousal index, total arousal index and arousal index related to respiratory stimuli and limb movement and AHI and LSaO(2) were also analyzed. Furthermore, the study group were divided into three subgroups according to AHI (< or = 10 times/h, 10 times/h < AHI < or = 20 times/h, > 20 times/h). Spontaneous arousal index, total arousal index and arousal index related to respiratory stimuli and limb movement were compared among the three groups. RESULTS: The increased total arousal index and arousal index related to respiratory stimuli and the decreased spontaneous arousal index of study group were significant as compared to those of control group (Mann-Whitney U, z value, -3.148, -3.866, -2.791; P value, 0.002, 0.000, 0.005, respectively). The increased arousal index related to respiratory stimuli were significant as being compared among the three groups. Arousal index related to respiratory stimuli was correlated with AHI (coefficient correlation: 0.734, P = 0.000). Other kinds of arousals and arousal index related to respiratory stimuli were not correlated with LSaO(2) (Spearman rank correlation analysis). When compared to control group, stage I increased and stage REM decreased and the difference was significant (z were -2.423, -3.519; P were 0.015, 0.000). CONCLUSIONS: The arousal index related to respiratory stimuli were increased and spontaneous arousal index were decreased in children with OSAHS. Arousal index related to respiratory stimuli is more suitable to show the degree of sleep fragment than other arousal index.

[The affection of antigen presentation ability, which sources from the spleen macrophage of Balb/c mouse during late gestation, on maternal Th2/Th1 type of immune].

OBJECTIVE: To study the relationship between antigen presentation ability of spleen macrophage and maternal Th2>Th1 immune bias in Balb/c mice during late pregnancy. METHODS: Balb/c mice during late gestation were adopted in our study, and mice of same species in estrus were used as control. With antigen stimulation, the spleen macrophages of Balb/c mice were pulsed as antigen presentation cells (APC). T cells sensitized previously by pulsed macrophage (1 degree APC) were cultured in mixture with macrophage pulsed by same antigen (2 degrees APC). An antigen special lymphocyte transformation test in vitro was used to evaluate the antigen presentation ability of spleen macrophage from mice of late gestation, and a flow cytometry method was used to measured the ration of CD4, CD8, IL-10 and IFN-gamma positive cell in T cells which had being induced to proliferate. RESULTS: When spleen macrophage from mice during late gestation was used as 1 degree APC, the proliferation of sensitized T cell induced by macrophage from late pregnancy mice used as 2 degree APC was no more intense than that from estrous mice (P > 0.05). When spleen macrophage from mice in oestrus was used as 1 degree APC, the proliferation of sensitized T cell induced by macrophage from late pregnancy mice as 2 degrees APC was lower intense than that from estrous mice (P < 0.05). The type of 1 degree APC did not affect the ratio of IL-10 positive T cell, and macrophage from late pregnancy mice could induce more IL-10 positive T cell than that from estrous mice when they were used as 2 degrees APC (P < 0.05). The type of 1 degree or 2 degrees APC did not affect the ratio of IFN-gamma positive T cell. CONCLUSION: The spleen macrophage from mice during late gestation is not an effective APC, but can induce maternal Th2 type of immune and maintain the Th1 type immune at a lower stage during pregnancy, which means it may has some important role in pregnancy.

[Analyses of polysomnogram in children suspected of obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To analyze polysomnogram characteristics of children with suspected obstructive sleep apnea hypopnea syndrome (OSAHS) and to explore the role of obstructive apnea index (OAI), apnea hypopnea index (AHI) and arousal index for pediatric OSAHS diagnosis. METHODS: Sixty one suspected pediatric OSAHS cases had overnight polysomnography for at least 8 h in a quiet, dark room. Sleep studies were interpreted according to diagnostic criteria of Guangzhou Children's Hospital (Obstructive apnea was defined as cessation of nose and mouth airflow, while the respiratory effort continues for any duration. Hypopnea was defined as reduction of oronasal flow > 50% accompanied by a desaturation of 0. 04 or greater) and Urumqi diagnostic criteria (Obstructive apnea was defined as cessation of airflow at the nose and the mouth, while the respiratory effort continues for at least two breaths. Hypopnea was defined as reduction of oronasal flow > 50% accompanied by a desaturation of more than 0.03, or/and by an arousal) respectively. The OAI, AHI and arousal index were recorded and analyzed according to the two different diagnostic criteria respectively. RESULTS: (1) Forty - one children (67.2%) had 206 obstructive apneas. Fifty - four children (88.5%) had 2249 obstructive hypopneas. Apnea - hypopnea events mainly occurred during rapid eye movement sleep. (2) OAI and AHI were analyzed by diagnostic criteria of Guangzhou Children's Hospital and Urumqi diagnostic criteria respectively. OAI < 1 was observed in 68. 9% and 75.4% children respectively and AHI < 5 occurred in 34.4% and 24.6% children respectively. (3) Statistically significant difference found between spontaneous arousal index and respiratory - related arousal index (z = -5.787, P = 0.000). CONCLUSIONS: As the criteria of pediatric OSAHS, arbitrary OAI number should be determined on the basis of large sample investigation, the significance of spontaneous arousal index still needs further investigation.

Gel electrophoresis: DNA Science Without the DNA!

The aim of this project is to develop a simple system for the teaching and demonstration of DNA gel electrophoresis. DNA gel electrophoresis requires the use of specialized apparatus, toxic reagents, expensive agarose gel, and DNA samples, as well as a considerable amount of valuable classroom time to complete. A systematic evaluation of suitable alternative materials and components for the simulation of DNA gel electrophoresis was undertaken. A tried and tested set of combinations is presented here for educators to use in hands-on classroom teaching, which does not require DNA, agarose, or Tris-borate-EDTA buffer. The use of common biological stains in place of DNA samples, agar-agar-based gels, and weak electrolyte solutions provides a simple, inexpensive, and highly reproducible system that is adaptable to instructional needs. The migration of multicolored bands during electrophoresis provides an intuitive, compelling demonstration of the concept of electrophoresis.