Influence of impaired right ventricular contractile reserve on exercise capacity in patients with precapillary pulmonary hypertension: A study with exercise stress echocardiography.

OBJECTIVES: Right ventricular (RV) contractile reserve reflects the ability of RV to accommodate the increased afterload and may play an essential role in the evaluation of precapillary pulmonary hypertension (PH). This study aimed to assess RV contractile reserve based on exercise stress echocardiography (ESE) and to determine the echocardiographic determinants of exercise capacity in patients with precapillary PH. METHODS: A total of 31 patients with precapillary PH and 15 age- and sex-matched healthy control subjects were prospectively recruited. All subjects underwent ESE to assess RV function at rest and under peak exercise. Changes in these parameters during exercise were calculated to quantify the RV contractile reserve. Patients with precapillary PH also underwent cardiopulmonary exercise test (CPET), and data pertaining to peak oxygen uptake (peak VO2 ) and minute ventilation/carbon dioxide production (VE/VCO2 ) were collected. RESULTS: Right ventricular contractile reserve including change in tricuspid annular plane systolic excursion (∆TAPSE), change in RV fractional area change (∆RVFAC), and change in Doppler-derived tricuspid lateral annular peak systolic velocity (∆S') was significantly depressed in precapillary PH patients compared with control subjects (P < 0.05). Parameters of RV function and RV contractile reserve were markedly associated with maximal exercise capacity (P < 0.05). ∆RVFAC was an independent predictor of peak VO2 (r2  = 0.601, P < 0.05). CONCLUSIONS: Assessment of RV contractile reserve facilitates identification of subclinical dysfunction and evaluation of clinical status and severity of precapillary PH. ESE as a noninvasive method may provide a comprehensive clinical assessment and facilitate therapeutic decision-making for these patients.

Incidental finding of an asymptomatic pulmonary valve papillary fibroelastoma: A case report.

Primary cardiac tumors are rare, but papillary fibroelastoma (PFE) is reportedly the most common form, which usually occurs on the left-side valves of the heart. However, PFE involving the tricuspid and pulmonary valves has also been documented. Although PFE is benign and seldom associated with valvular dysfunction, the associated embolic complications may lead to serious consequences. Most patients with PFE lack specific clinical symptoms and the diagnosis is incidental. Surgical resection is the mainstay treatment for PFE in order to prevent the occurrence of embolic complications. In this report, we present a case of a rare asymptomatic PFE of the pulmonary valve, which was incidentally noted during a routine examination with transthoracic echocardiography (TEE). There was neither valvular dysfunction nor hemodynamic change. The PFE was surgically removed, and the diagnosis was further confirmed with histopathology.

17ß-estradiol preserves right ventricular function in rats with pulmonary arterial hypertension: an echocardiographic and histochemical study.

Pulmonary arterial hypertension (PAH) is more prevalent in females. Paradoxically, female patients have better right ventricular (RV) function and higher survival rates than males. However, the effects of 17ß-estradiol (E2) on RV function in PAH has not been studied. Twenty-four male rats were exposed to monocrotaline (MCT) to induce experimental PAH, while treated with E2 or vehicle respectively. Together with eight control rats, thirty-two rats were examined by echocardiography 4 weeks after drug administration. Echocardiographic measurement of RV function included: tricuspid annular plane systolic excursion (TAPSE), RV index of myocardial performance (RIMP), RV fractional area change (RVFAC) and tricuspid annular systolic velocity (s'). RV free wall longitudinal strain (RVLSFW) and RV longitudinal shortening fraction (RVLSF) were also used to quantify RV function. RV morphology was determined by echocardiographic and histological analysis. TAPSE, RVFAC and s' were reduced, and RIMP was elevated in the MCT-treated group and vehicle-treated group, when compared with control group (P < 0.01). TAPSE, RVFAC and s' in the E2 group were higher, while RIMP was lower than those in the MCT-treated group and vehicle-treated group (P < 0.01). Myocardial functional parameters (RVLSFW and RVLSF) were also higher in the E2 group. Enhanced serum E2 levels were closely correlated with the improvement in RV functional parameters and enhancement of serum BNP levels (P < 0.01 for all groups). RV function decreased significantly in male rats with MCT-induced PAH, while E2 exhibited a protective effect on RV function, suggesting that E2 is a critical modulator of sex differences in PAH.

Decreased biventricular mechanics and functional reserve in nonobstructive hypertrophic cardiomyopathy patients: implications for exercise capacity.

The present study investigated the changes of biventricular mechanics at rest and during exercise and examined the association between exercise capacity and biventricular mechanics and functional reserve in nonobstructive hypertrophic cardiomyopathy (NHCM) patients. A total of 50 NHCM patients and 25 controls were consecutively recruited for this study. Using echocardiography and two-dimensional speckle-tracking imaging, an experienced echocardiographer determined the following indices: RV free wall longitudinal strain (RVFWLS), LV global longitudinal strain (LVGLS), strain rate (SR), and functional reserve of strain values. We also investigated the relationships between biventricular mechanics and exercise capacity using metabolic equivalents (METs). NHCM patients had lower RVFWLS, LVGLS, systolic SR, early diastolic SR, and systolic and diastolic reserve during exercise compared to controls. An association of biventricular mechanics (LVGLS, RVFWLS) with exercise capacity at rest and during exercise was established. Multivariable logistic regression revealed that RVFWLS and LVE/e' during exercise (RVFWLS-exe, E/e'-exe) were independent predictors of exercise intolerance. Receiver operating characteristic curve analysis indicated that LVE/e'-exe had a higher area under the curve for predicting exercise intolerance in NHCM patients. In hierarchical analysis, RVFWLS-exe provided an incremental predictive value of exercise intolerance over LVGLS during exercise (LVGLS-exe) and LVE/e'-exe. LVE/e'-exe also changed incrementally compared to LVGLS-exe and RVFWLS-exe. NHCM patients have decreased biventricular mechanics at rest and during exercise and impaired biventricular functional reserve, and biventricular mechanics are associated with functional capacity. We propose that simultaneous evaluation of biventricular function should provide incremental predictive value for exercise intolerance.

Polymorphism of five short tandem repeat systems in Chinese Han population in Chengdu / 法医学杂志

OBJECTIVE@#To obtain population genetic data of loci D11S4951, D11S4957, GATA193H05, D2S2951, and D6S2421 in Han population in Chengdu area and to validate the value of their forensic application.@*METHODS@#Blood samples were collected in EDTA tubes from unrelated individuals. DNAs were extracted with Chelex-100 and were analyzed by PCR and horizontal PAGE followed by silver staining.@*RESULTS@#Alleles 7, 10, 8, 6 and 8 were found in 5 STR loci, respectively. No deviations from Hardy-Weinberg balance were observed. The heterozygosities observed were 0.743, 0.772, 0.833, 0.650 and 0.800, respectively. The chances of exclusion were 0.497, 0.549, 0.662, 0.356 and 0.599, and the discrimination powers were 0.863, 0.912, 0.947, 0.829 and 0.931.@*CONCLUSION@#All of the five loci studied may be useful markers for individual identification and paternity testing.

Further study on heterogeneic basis of complement C8 beta deficiency / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>In Caucasian population, the most common molecular basis for C8 beta deficiency s a single C to T transition in exon 9 of C8 beta gene resulting in a stop codon. In previous family studies, two individuals were identified with C8 beta complete deficiency and were found to be only heterozygous for this mutation. This study was conducted by the present authors in search of other possible causes for these two C8 beta deficient individuals.</p><p><b>METHODS</b>Using direct DNA sequence analysis of all exon-specific PCR products of the C8 beta gene from these two C8 beta deficient patients and their descendants.</p><p><b>RESULTS</b>Two other C to T transitions at base 298 and 388 in exon 3 were detected, which could also create a termination codon. The descendants from one of the deficient patients were also analysed for the mutations, and it could be demonstrated that the two C to T mutations in exons 9 and 3 are segregating independently.</p><p><b>CONCLUSION</b>These two mutations, which create a termination codon, are sufficient to explain the complete C8 beta deficiency in both patients.</p>

Analysis of p53 gene mutation in esophageal exfoliative cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore the feasibility of detecting p53 gene mutation in exfoliative esophageal cells, and compare gene mutation between precancerous lesions and normal esophageal exfoliative cells and correlate p53 gene mutation with esophageal carcinogenesis.</p><p><b>METHODS</b>Forty-eight samples (24 normal squamous epithelia and 24 severe squamous dysplasia) were obtained by balloon cytologic technique from a high incidence area, Yanting county, Sichuan Province, China in 1982. p53 gene mutations in exons 5 and 7 were analyzed by PCR-SSCP.</p><p><b>RESULTS</b>p53 genes were detected in all samples. Five samples with p53 mutation were detected in exon 7 and no mutation was detected in exon 5 in 24 severe dysplasia samples. Three of the 5 samples with mutation in exon 7 developed esophageal cancer in 1992, 1994 and 1996 respectively. No p53 gene mutation was detected in exon 5 and 7 in normal exfoliative samples.</p><p><b>CONCLUSION</b>p53 mutation may have occurred in the precancerous lesions which contributes in the initiation of human esophageal carcinogenesis.</p>

A study of genetic polymorphism of the STR locus D2S441 in Chinese Han population in Chengdu / 法医学杂志

Using PCR and PAG, followed by silver staining, the tetrameric STR D2S441 locus was studied in 260 unrelated Chinese individuals living in Chengdu. 9 alleles and 26 genotypes were observed. The range of fragment size was 131 bp to 155 bp. The genotype distribution of D2S441 locus in Han population was in accordance with Hardy-Weinberg equilibrium. Family survey confirmed Mendelian inheritance of alleles. The discriminating power (Dp), observed heterozygosity (H), polymorphism information content (PIC) and power of exclusion (PE) were 0.9084, 0.7885, 0.7390 and 0.5778 respectively. The results demonstrated that this locus was highly polymorphic and could be used for forensic identification and paternity testing.

Study on the construction of standard D1S549 allelic ladder via molecular cloning and its genetic polymorphism in Chinese three populations / 法医学杂志

OBJECTIVE@#To resolve the problem of the accuracy and standardization of STR-PCR typing in forensic practice, we have designed a new method to produce standard D1S549 allelic ladder.@*METHODS@#Eight different PCR amplified D1S549 allelic fragments were isolated from the gel, eluted into the distilled water and re-amplified by PCR. The purified allelic fragments were then blunt-end subcloned individually into the pUC plasmid vectors and transfected into competent E. coli DH5 alpha cells.@*RESULTS@#The sequencing results confirmed that the size and the construe of the inserts were correct. The recombinant plasmids DNA with 8 inserts were then used as templates for re-amplification to generate D1S549 standard ladder, with which the genetic polymorphisms of D1S549 locus in Chinese Han population in chengdu, Hui population in Gansu and Wei population in Xinjiang were studied.@*CONCLUSION@#The results showed that the standard ladder made via this method is excellent, and D1S549 locus is robust for genetic research and forensic application.