[Mutation and clinical relevance in a large cohort of unrelated Chinese patients with hypertrophic cardiomyopathy].

OBJECTIVE: To explore the genetic basis and phenotypic correlation with disease severity in a large cohort of Chinese patients with hypertrophic cardiomyopathy (HCM). METHODS: A total of 179 unrelated Chinese HCM patients admitted to our department from 2002 to 2011 were enrolled in this study. Direct gene sequencing of ß-myosin heavy chain (MYH7), myosin binding protein-C ( MYBPC3), and cardiac troponin T (TNNT2) were performed and clinical data were obtained in these patients. RESULTS: A total of 34 mutations were identified in 40 patients (22.3%), 79.4% (27/34) mutations occurred only once and a possible hot spot, A26 in MYH7, was found. Distribution of mutations was 52.9% (18/34) (MYBPC3), 35.3% (12/34) ( MYH7) and 11.8% (4/34) (TNNT2) respectively. Double mutations were identified in 2.2% (4/179) patients. Genotype-positive patients were associated with an earlier symptom onset, severer left ventricular hypertrophy, a higher incidence of syncope, and were more likely to have positive family history of HCM or sudden cardiac death (SCD) , and were more likely to progress into heart failure (24.2% vs. 5.0%, P = 0.002) and at a higher risk of SCD (9.1% vs. 0, P = 0.009) during the 6.5-year follow-up. No statistical difference in any clinical parameters and outcomes was found between patients carrying MYBPC3 and MYH7 mutations. Double mutations were associated with malignant clinical progression in this cohort. Different phenotype severity could be seen in HCM patients with same genotype (e. g. MYH7-1736T, TNNT2-R92W). CONCLUSION: MYBPC3 is the most predominant gene mutation in this HCM cohort. The presence of a sarcomere mutation in patients with HCM is associated with poor clinical outcome, although no specific genes or mutations can exactly predict the severity of clinical phenotypes.

Clinical effect of combined nickel-titanium instruments and ultrasonic technique and warm vertical technique used in one-visit endodontic treatment for infected root canals / 中国基层医药

Objective To evaluate the effect of one-visit endodontic treatment for infected root canals with combination of nickel-titanium instruments and ultrasonic technique and warm vertical technique.Methods According to treatment,90 teeth were randomly divided into experimental and control groups.Two groups were used nickel titarlium root canal preparation.Experimental group:51 teeth for ultrasonic root canal irrigation,and warm vertical technique was employed to fill the root canal.Control group:39 teeth for rinse syringes,and warm vertical technique was employed to fill the root canal.Washing fluid was 2％ sodium hypochlorite.The root canal filling was observed after a week and one year of postoperative pain response.Results A week later,two groups of post-operative pain showed that there was significant difference in responses (x2 =15.525,P ＜ 0.05).One year later,the two groups showed no significant difference in efficacy(x2 =0.085,P ＞ 0.05).Conclusion The combination of nickel-titanium instruments and ultrasonic irrigation technique and warm vertical obturation,for the treatment of infected root canals was a method to complete the root canal filling,could reduce both the number of patients subsquent visits and the postoperative pain response,while it could improve the quality of root canal filling.

The lowest dosages of mifepristone and misoprostol to terminate ultra-early pregnancy / 中华妇产科杂志

Objective To explore the lowest effective dosage of mifepristone combined with misoprostol in terminating ultra-early pregnancy.Methods All the cases of ultra-early pregnancy classified by amenorrhea days,β-hCG and vaginal B-ultrasonic were randomly divided into two groups.One hundred cases in G1 group (minimized dosage) were orally administered 25 mg mifepristone once a day for 2 days and combined with 200 μg misoprostol 48 hours later,while 150 mg mifepristone combined with 600 μg misoprostol 48 hours later were given to 100 cases in G2 group (normal dosage).All cases were observed for 6 hours after taking misoprostol and returned for assessment three days later.Results None missing.Expulsion of conceptus:G1 and G2 group were 22 (22.0％,22/100) and 25 (25.0％,25/100;P ＞ 0.05).Failure rate:cases with incomplete abortion were 1 (1.0％,1/100) and 2 (2.0％,2/100) in G1 and G2 group,hospitalization for suspected ectopic pregnancies both was 1 (1.0％).Bleeding:bleeding cases during the administration of mifepristone in G1 and G2 group were 71 (71.0％,71/100) and 78 (78.0％,78/100; P＞0.05); the mcan bleeding time were (5.3 ± 1.4) days and (6.0± 1.5) days (P ＜0.01).Other side effects:in G1 group,majority showed light nausea (7.0％,7/100) and light abdominal pain (20.0％,20/100).Menses recovery:99 (99.0％,99/100) for G1 group and 98 (98.0％,98/100) for G2 group to recovery on scheduled time.Satisfactions:both were 99 (99.0％,99/100).Except mean bleeding days and side-effects,the differences above showed no significance (P ＞ 0.05).Conclusion It is safe and effective treatment with the lowest dosages of mifepristone and misoprostol to terminate ultra-early pregnancies.

Clinical significance of ultrasonic scanning in detecting umbilical abnormality and measuring notch depth of nuchal cord entanglement / 中华全科医师杂志

Type B ultrasonic scanning was performed routinely for 10 944 pregnant women at their third semester when they visited outpatient department or were admitted to our hospital during January 2004 to December 2008, and their fetal heart rate, amniotic fluid, umbilical cord and neonate conditions were monitored and recorded during delivery. The sensitivity and specificity of type B ultrasonic were 95.74% (3301/3448) and 96. 25 % (7215/7496). Umbilical abnormality was diagnosed in 3448 pregnancies by type B ultrasonic scanning, with prevalence of 31.51%, cesarean section was performed in 44.00 %, fetal distress occurred in 18. 27% of them, 15.46% of them with Apgar score equal to or less than seven, and fetal death occurred in 2. 41% of them, all significantly higher than those in pregnant women without umbilical abnormal (23. 77%, 8. 56%, 7.84% and 1.36%, respectively, all P ＜0. 01 ). Cesarean section was performed in 41.90 % of those with 0. 8 cm or more in the notch depth of nuchal cord entanglement,fetal distress occurred in 29.76% of them, 25.30% of them with Apgar score equal to or less than seven and fetal death occurred in 4. 05% of them, all significantly higher than those in pregnant women with the notch depth less than 0. 8 cm (20. 22%, 8. 60%, 9. 26% and 0. 54%, respectively, all P ＜0. 01 ). Type B ultrasonic scanning plays an important role in clinical diagnosis for umbilical abnormality, guiding selection of delivery method and improving neonatal prognosis.

Dobutamine infusion for unmasking long QT syndrome and torsades de pointes.

Prolonged QT interval is usually seen on routine electrocardiogram (ECG), but in some patients it may only be seen immediately before the evolution of torsades de pointes (Tdp). To unmask the potential risk of Tdp in a patient with normal or borderline prolongation of QTc interval and recurrent syncope, dobutamine was given intravenously at a rate of 20 microg/kg/min. Strikingly, QTc prolongation was induced along with syncope after dobutamine infusion. Torsades de pointes occurred 5 d later when the patient received an implantable cardioverter defibrillator (ICD). Genetic testing revealed a mutation of the KNCQ(1)-gene encoding serine instead of glycine. The patient was treated with 75 mg of metoprolol twice daily, and at 12 mo follow-up he had no syncope or chest tightness. The ICD revealed no ventricular tachyarrhythmias or therapy delivered.

Association of genetic polymorphisms in the fibrinogen and platelet glycoprotein genes with unstable angina in Chinese patients.

BACKGROUND: Inherited predisposition has been associated with coronary artery disease (CAD) in the white population. HYPOTHESIS: The objective of this study was to investigate the association between the risk of unstable angina (UA) and genetic factors believed to be associated with an increased tendency toward thrombosis (the variable number of tandem repeats [VNTR] polymorphism of the platelet glycoprotein [GP] Ib alpha gene, Pl(A1/A2) of the platelet GP IIIa gene, 448G/A of the Bbeta fibrinogen gene and Thr312Ala of the Aalpha fibrinogen gene) in Chinese patients with UA. METHODS: We performed a case/control study evaluating 69 Chinese patients (43 men, 26 women) with UA and 69 control subjects without CAD, individually matched for age and gender. The restriction fragment length polymorphism (RFLP) method was used to determine the genetic polymorphisms. RESULTS: The frequencies of GP Ib alpha C/B genotype and Bbeta fibrinogen 448A allele were higher in patients with UA (46.4 vs. 30.4%, odds ratio [OR] 1.977, 95% confidence interval [CI] 0.98-3.97, p = 0.054, and 49.3 vs. 20.3%, OR 3.816, 95% CI 1.797-8.103, p = 0.000, respectively). Only four subjects (two cases, two controls) with GP IIIa Pl(A2) allele were found, and there was no association between Aalpha fibrinogen Thr312Ala polymorphism and UA. CONCLUSIONS: Chinese patients with UA had increased frequencies of GP Ib alpha C/B genotype and Bbeta fibrinogen 448A allele. These data suggest that some genetic factors may influence the development of UA.

Mutation analysis of potassium channel genes KCNQ1 and KCNH2 in patients with long QT syndrome / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To determine mutations of two common potassium channel subunit genes KCNQ1, KCNH2 causing long QT syndrome (LQTS) in the Chinese.</p><p><b>METHODS</b>Thirty-one Chinese LQTS pedigrees were characterized for mutations in the two LQTS genes, KCNQ1 and KCNH2, by sequencing.</p><p><b>RESULTS</b>Two novel KCNQ1 mutations, S277L in the S5 domain and G306V in the channel pore, and two novel KCNH2 mutations, L413P in the transmembrane domain S1 and L559H in the transmembrane domain S5 were identified. The triggering factors for cardiac events developed in these mutation carriers included physical exercise and excitation. Mutation L413P in KCNH2 was associated with the notched T wave on ECGs. Mutation L559H in KCNH2 was associated with the typical bifid T wave on ECGs. Mutation S277L in KCNQ1 was associated with a high-amplitude T wave and G306V was associated with a low-amplitude T wave. Two likely polymorphisms, IVS11 + 18C > T in KCNQ1 and L520V in KCNH2 were also identified in two LQTS patients.</p><p><b>CONCLUSIONS</b>The mutation rates for both KCNQ1 (6.4%) and KCNH2 (6.4%) are lower in the Chinese population than those from North America or Europe.</p>

Clinical Study on Morphological Characteristics of Placenta in Severe Pregnancy Induced Hypertension / 中华妇产科杂志

Objective To study morphological characteristics of placenta in severe pregnancy induced hypertension (SPIH) and its relationship to pregnant outcome. Methods Morphological changes were observed by light microscopy; Blood biochemical analyses were used to predispose pregnant outcome. Results Difference in pathological changes of placental bed between normal term pregnancy (NTP) and SPIH groups was significant: the placental weight, proliferation of cytotrophoblasts, numbers of the placental villi with syncytial knots, thickness of basal lamina, fibrinoid necrosis and deposition of matrix, stromal edema and fibrosis of villi, the vascular numbers of villi, stasis; lack of physiologic changes in decidual spiral arteries. Clinical examination showed that the rate of anemia, thrombocytopenia, blood concentration, hypoproteinemia, ascites, eye ground artery spasm in SPIH were higher in NIT. Conclusions Pathological changes of placenta play important roles in development of SPIH, and the pathological changes are paralleled with the severity of the disease.

Characteristics of transient outward potassium current in repolarization 1 phase from the canine right ventricular mid-myocardial cells / 中国病理生理杂志

AIM: To examine the electrophysiological characteristics of transient outward potassium current(Ito 1) in repolarization 1 phase from the canine right ventricular M cells. METHODS: By use of whole cell patch-clamp technique, we quantitatively researched the ionic intensity, density of Ito 1 and the notch magnitude of action potential in repolarization 1 phase. RESULTS: (1) The activating process of Ito 1 of canine right ventricular M cells presented evident voltage-dependency. Under the condition of 37℃, 5 000 ms, 0 mV and +70 mV, the average peak Ito 1 intensity of right ventricular M cell were (690?380) pA and ( 3 130? 1 910) pA, respectively (P