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To investigate the characteristic of nasopharyngeal microbiota at different states of Mycobacterium tuberculosis (MTB) infection.Participants were recruited from a chest hospital and were divided into three groups: the active tuberculosis (ATB) group, the latent TB infection (LTBI) group and the healthy control (HC) group. Nasopharyngeal microbiota was analyzed by 16S rRNA sequencing and clinical laboratory test results of ATB patients were collected and statistically analyzed.Eleven ATB patients, 19 LTBI individuals and 18 healthy controls were included. Compared with LTBI group, Proteobacteria (P=0.04) and Gammaproteobacteria (P=0.01) increased in the ATB group. Compared with HC group, Pseudomonadales (P=0.03) and Moraxellaceae (P=0.04) increased, while Bacillales (P=0.04) and Lachnospiraceae (P=0.03) decreased in ATB group. Furthermore, Staphylococcus and Corynebacterium accounted for 70-80% in HC and LTBI groups. While in ATB group, they were less than 40%. Moreover, relative abundance of Corynebacterium, Corynebacteriaceae and Mycobacteriales was positively correlated with serum adenosine deaminase while negatively correlated with albumin, hemoglobin, and platelet counts in ATB patients.The composition of nasopharyngeal microbiota changed significantly after MTB infection. The correlations between Corynebacterium and nutritional status (hemoglobin and albumin), immune-related molecules (adenosine deaminase) and inflammation-related indicators (platelet) in ATB patients deserve further exploration.

A discrete element method (DEM) model of the crushing process of a toothed double-roll crusher (TDRC) is established using the bonded particle model. DEM results and experimental data are compared quantitatively and a relatively good agreement is observed. The effects of rotation speed and structure of crushing rolls on the performance of TDRC are investigated numerically. The results show that when the rolls' speed is relatively high, the nipping condition would be improved, and more cracks could be created to release the increasing strain energy, generating more fractions of small sizes in the products. But, when rolls' speed exceeds 150 rpm, the crushing performance would not be significantly improved. A reasonable working gap and better nipping behaviour are obtained using the spiral-tooth-roll or the staggered-tooth-roll. The validated DEM model could be applied to gain a fundamental understanding of the crushing mechanisms of TDRC.

Heat stress is one of the major environmental stressors challenging the global poultry industry. Identifying the genes responsible for heat tolerance is fundamentally important for direct breeding programs. To uncover the genetic basis underlying the ambient temperature adaptation of chickens, we analyzed a total of 59 whole genomes from indigenous chickens that inhabit South Asian tropical regions and temperate regions from Northern China. We applied F

Nearly 200 million people have been diagnosed with COVID-19 since the outbreak in 2019, and this disease has claimed more than 5 million lives worldwide. Currently, researchers are focusing on vaccine development and the search for an effective strategy to control the infection source. This work designed a detection platform based on Surface-Enhanced Raman Spectroscopy (SERS) by introducing acetonitrile and calcium ions into the silver nanoparticle reinforced substrate system to realize the rapid detection of novel coronavirus. Acetonitrile may amplify the calcium-induced hot spots of silver nanoparticles and significantly enhanced the stability of silver nanoparticles. It also elicited highly sensitive SERS signals of the virus. This approach allowed us to capture the characteristic SERS signals of SARS-CoV-2, Human Adenovirus 3, and H1N1 influenza virus molecules at a concentration of 100 copies/test (PFU/test) with upstanding reproduction and signal-to-noise ratio. Machine learning recognition technology was employed to qualitatively distinguish the three virus molecules with 1000 groups of spectra of each virus. Acetonitrile is a potent internal marker in regulating the signal intensity of virus molecules in saliva and serum. Thus, we used the SERS peak intensity to quantify the virus content in saliva and serum. The results demonstrated a satisfactory linear relationship between peak intensity and protein concentration. Collectively, this rapid detection method has a broad application prospect in clinical diagnosis of viruses, management of emergent viral infectious diseases, and exploration of the interaction between viruses and host cells.

To evaluate the relationship between myocardial extracellular volume (ECV) fraction measured using dual-energy computed tomography with late iodine enhancement (LIE-DECT) and risk of heart failure (HF) in patients without coronary artery disease (CAD), and to evaluate the relationship between ECV and left ventricular structure and function.Sixty consecutive HF patients without CAD and 60 consecutive participants without heart disease who underwent coronary CT angiography (CCTA) following LIE-DECT were included. ECV of the left ventricle was calculated from the iodine maps and hematocrit levels using the American Heart Association (AHA) 16-segment model. Cardiac structural and functional parameters were collected including left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), left ventricular ejection fraction (LVEF), left atrial volume (LAV), interventricular septal thickness (IVST), and N-terminal pro-brain natriuretic peptide (NT-pro-BNP).ECV in HF patients without CAD (31.3 ± 4.0 %) was significantly higher than that in healthy subjects (27.1 ± 3.7 %) (P 0.001). Multivariate linear analysis revealed that ECV was associated with age (β = 0.098, P = 0.010) and hypertension (β = 2.093, P = 0.011) in all participants. Binary logistic regression analysis showed that after adjusting for age, sex, body mass index (BMI), smoking, and drinking, ECV was a risk factor affecting the occurrence of HF in those without CAD (OR = 1.356, 95 %CI：1.178-1.561, P 0.001). A positive correlation was found between ECV and NT-pro-BNP, LVEDV, LVESV, and LAV (r = 0.629, 0.329, 0.346, and 0.338, respectively; all P 0.001) in all participants.ECV could be measured using LIE-DECT iodine maps. ECV elevation was a risk factor for HF without CAD and correlated with cardiac structure and function.

Fiber-based flexible electronics have become one of the most demanding sensing elements by various wearable applications. However, many of those flexible electronics are facing the major challenge of high electromechanical hysteresis. In this paper, polypyrrole-coated strain sensors based on polyurethane yarns and hybrid polyurethane yarns were fabricated and tested. To lower the mechanical and electromechanical hysteresis of the yarn and yarn-based sensors, micro-morphology and electromechanical property of the yarn-based sensors were observed and analyzed, especially the existence and generation of cracks on conductive films of the sensors. The effect of the covered yarn structure on the electromechanical property of the sensors was discussed. Through the results of tensile tests, the electromechanical properties of the yarn-based sensors were characterized, with contributing factors of electromechanical hysteresis examined and reason for the nonlinear electrical resistance-strain relationship elaborated. Furthermore, the covered yarn structure was found stable, with fewer cracks under tension. It’s recommended that hybrid PU yarns and corresponding yarn-based sensors shall be firstly considered for future research, for relatively small mechanical and electromechanical hysteresis.

Flexible sensors based on the highly elastic Polyurethane (PU)-containing textile substrates have been frequently incorporated in enormous wearable applications. However, the desirable sensing properties such as stable sensitivity, small hysteresis and good repeatability depend on the mechanical resilience of the textile substrates. This paper conducts a systematic investigation into the mechanical hysteresis of the PU-containing textile substrates, from fibers to yarns and then fabrics. The impact of fiber materials, yarn structures, and fabric constructions on the overall tensile properties of the PU-containing substrates were examined. It was found that fibers of high elasticity, stable yarn structure with excellent recovery, as well as appropriate fabric construction are effective to reduce the mechanical hysteresis of the textile substrates. Coated strain sensors based on different substrates were then fabricated. Results show that smaller mechanical hysteresis of the PU-containing substrates generally led to lower electromechanical hysteresis and better repeatability of sensors. This paper gives all-round consideration of the fibers and structure features of substrates to provide recommendation for reducing mechanical and electromechanical hysteresis of sensors based on PU-containing textiles and benefiting the design and optimization of other flexible sensors. Keywords: Polyurethane-containing textile, Textile substrates, Mechanical hysteresis, Coated sensors, Electromechanical hysteresis

Photoluminescence properties of [Ru(bpy)2(tatp)]2+ (bpy = 2,2′-bipyridine and tatp = 1,4,8,9-tetra-aza-triphenylene) bound to a BSA–SWCNTs film (BSA = bovine serum albumin and SWCNTs = single-walled carbon nanotubes) upon incorporation of [Co(phen)3]3+ (phen = 1,10-phenanthroline) are first investigated by means of steady-state and time-resolved fluorescence spectroscopy. The BSA-bound [Ru(bpy)2(tatp)]2+ shows tunable luminescence properties by [Co(phen)3]3+, where an increasing amount of BSA is found to increase the emission intensity of [Ru(bpy)2(tatp)]2+–BSA dyad with binding constant of 1.9 × 102 M−1, and however decrease the luminescence of [Ru(bpy)2(tatp)]2+–BSA–[Co(phen)3]3+ triad with quenching constant of 2.4 × 103 M−1. Moreover, BSA is combined with SWCNTs to construct BSA–SWCNTs bio-nanohybrids, which mediate the photo-induced electron transfer (PET) between [Ru(bpy)2(tatp)]2+ and [Co(phen)3]3+, representing a dynamic luminescence quenching process. On basis of such a PET, [Ru(bpy)2(tatp)]2+ and [Co(phen)3]3+ are assembled on the surfaces of BSA–SWCNTs to fabricate a photoanode and a cathode, respectively, showing detectable photovoltaic response. The present study could provide a versatile platform for the fabrication and evaluation of nanoscale optoelectronic devices.

Farnesyltransferase (FT), an essential enzyme at the downstream of mevalonate pathway, was reported to be upregulated in hypertrophic cardiomyocytes of spontaneously hypertensive rats (SHRs) compared with myocardium of Wistar-Kyoto rats (WKYs). This upregulation was accompanied with cardiac remodeling. This study was designed to determine whether FT inhibition can alter cardiac remodeling in SHRs.Twelve-week-old SHRs were randomized to receive infusion of either NS or FTI-276 (307 μg/kg/d i.v. each n=10). WKY rats served as normal controls (n=6). Echocardiography was performed before and after intervention. SHR hearts were perfused ex vivo for the evaluation of cardiac performance, collagen deposition and biochemical changes (activation of Ras, extracellular-signal regulated kinases/ERK1/2, procollagen type І/Ш, TGF-β1, connective tissue growth factor/CTGF, and bone morphogenetic protein-7/BMP-7 expression).FTI-276 intervention decreased interventricular septum wall thickness at end- diastole (IVSd) and relative wall thickness (RWT) of SHRs (P0.05). Three week intervention with FTI-276 attenuated hydroxyproline content (P0.05), collagen deposition (P0.01), Ras activation, ERK1/2 phosphorylation (P0.01) and mRNA expression of procollagen type I, TGF-β1 and CTGF and elevated mRNA expression of BMP-7 (P0.05) in left ventricle of SHRs.The present study indicated that FT inhibition could attenuate myocardial fibrosis and partly improve cardiac remodeling in SHRs. The beneficial effects might be mediated through suppression of the activation of Ras and ERK1/2 phosphorylation pathway. The enhanced mRNA expression of BMP-7 with inhibition of TGF-β1 and CTGF mRNA expression might be an important mechanism.

Farnesyl pyrophosphate synthase (FPPS), as a key branchpoint of the mevalonate pathway, catalyzes the synthesis of isoprenoid intermediates. The isoprenoid intermediates are needed for protein isoprenylation to participate in cardiac remodeling. We have previously demonstrated that both knockdown of FPPS with small interfering RNA and inhibition of FPPS by alendronate could prevent Ang II-induced hypertrophy in cultured cardiomyocytes. In this study, we evaluated the effects of FPPS inhibition in Ang II-mediated cardiac hypertrophy and fibrosis in vivo. Wild type mice were separately treated with saline, Ang II (2.88 mg/kg per day), FPPS inhibitor alendronate (0.1 mg/kg per day), or the combination of Ang II (2.88 mg/kg per day) and alendronate (0.1 mg/kg per day) for 4 weeks. The results showed that Ang II increased FPPS expression, and the increases of Ang II-induced synthesis of the isoprenoid intermediates, FPP and GGPP, were significantly inhibited by FPPS inhibitor. In the meantime, FPPS inhibition attenuated Ang II-mediated cardiac hypertrophy and fibrosis as indexed by the heart weight to body weight ratio, echocardiographic parameters, histological examinations and expression of ANP and BNP mRNA. Furthermore, it was also found that FPPS inhibitor attenuated Ang II-induced increases of RhoA activity and p-38 MAPK phosphorylation and TGF-β1 mRNA expression. In conclusion, FPPS might play an important role in Ang II-induced cardiac hypertrophy and fibrosis in vivo, at least in part through RhoA, p-38 MAPK and TGF-β1.

Background Diabetic hearts are vulnerable to ischemia/reperfusion (I/R) injury. Pretreatment with exogenous calcitonin gene-related peptide (CGRP) exerts a cardioprotective effect against myocardial I/R injury. Our previous study found that the CGRP level was decreased in diabetic hearts. This study aimed to investigate whether up-regulation of CGRP could reduce I/R injury in diabetic hearts. Methods and results Adenovirus encoding the CGRP gene (Ad-CGRP) was injected intramyocardially in mice with or without streptozotocin (STZ) treatment. Three days after injection, the hearts were subjected to in vivo and in vitro I/R. Myocardial infarct size, cardiac function, lactate dehydrogenase (LDH) level in plasma and effluents, and cell mitochondrial function were measured. After ischemia (30min) and reperfusion (24h) in vivo , diabetes mellitus (DM) mice had greater myocardial infarct size than their nondiabetic counterparts, and released more LDH in plasma. However, CGRP gene transfer reduced myocardial infarct size and plasma LDH level in both non-DM and DM hearts. After 30min global ischemia and 40min reperfusion in vitro , the DM hearts demonstrated increased left ventricular end-diastolic pressure (LVEDP) and effluent LDH level, and decreased left ventricular developed pressure (LVDP), coronary flow (CF), as well as cell mitochondrial function, when compared with the non-DM hearts. Again, CGRP gene transfer could protect against I/R injury in both non-DM and DM hearts. Conclusions Adenovirus-mediated up-regulation of CGRP gene expression protects diabetic hearts against I/R injury.

The Rho guanosine triphosphatases (Rho GTPases) family, including RhoA, plays an important role in angiotensin II (Ang II)-mediated cardiac hypertrophy. Farnesylpyrophosphate synthase (FPPS)-catalyzed isoprenoid intermediates are vital for activation of RhoA. The present study was designed to investigate the role of FPPS in myocardial hypertrophy mediated with Ang II. First, we demonstrated that FPPS expression was elevated both in cultured neonatal cardiomyocytes (NCMs) following Ang II treatment and in the hypertrophic myocardium of 18-week-old spontaneously hypertensive rats (SHRs). Then, the importance of FPPS was assessed by RNA interference (RNAi) against FPPS in NCMs. Successful FPPS silencing in NCMs completely inhibited the hypertrophy marker genes of β-myosin heavy chain (β-MHC) and brain natriuretic peptide (BNP), as well as cell surface area. Furthermore, FPPS knockdown prevented elevated RhoA activity compared with non-silenced controls. Similarly, increased-phosphorylation of p-38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinases (MAPK) by Ang II was attenuated. In vivo gene transfer also attenuated hypertrophic responses as indexed by left ventricular weight/body weight (LVW/BW), heart weight/body weight (HW/BW), and echocardiography, as well as expression of β-MHC and BNP mRNA in SHRs. In conclusion, FPPS with RhoA associated p-38 and JNK MAPK signaling might play an important role in Ang II-induced cardiac hypertrophy.

Farnesyl pyrophosphate synthase (FPPS, EC 2.5.1.10), an essential enzyme in the mevalonate pathway, catalyzes the synthesis of isoprenoid intermediates. The isoprenoid intermediates are needed for protein isoprenylation of RhoA for its function on regulation of endothelial nitric oxide synthase (eNOS). We previously reported that FPPS were upregulated in spontaneously hypertensive rats (SHR) when compared with Wistar-Kyoto rats (WKY), and this was accompanied by development of endothelial dysfunction. Five-week-old male rats were daily gavaged with vehicle or an FPPS inhibitor (alendronate, 1 or 10mg/kg). After 12-week administration of alendronate, endothelium-dependent and -independent vasorelaxation were measured in isolated aortic rings. Twelve-week of alendronate (10mg/kg/day) treatment restored the impaired endothelium-dependent vasodilation in SHR. Furthermore, long-term treatment with an FPPS inhibitor significantly suppressed RhoA activation and increased phospho-eNOS/eNOS ratio. In conclusion, chronic treatment with an FPPS inhibitor improves the endothelial function in SHR, and the upregulation of phospho-eNOS/eNOS ratio with inhibition of RhoA activation may be an important mechanism.

Sodium aescinate (SA) is used as a vasoactive drug in clinical treatment. This study was designed to investigate the effects of SA on rat isolated thoracic aorta and the possible mechanisms.Isometric tension was recorded in response to drugs in organ bath.The effects of SA obeyed an all-or-nothing response. SA in relatively low dose (or = 50 microg/ml) had an endothelium-independent contractile effect in rat aorta (P0.01), which depended on extracellular Ca(2+) influx via L-type Ca(2+) channel (P0.05). SA in relatively high dose (or = 100 microg/ml) also induced vasoconstriction in Ca(2+)-free medium (P0.01), which was independent of the activity of inositol-1,4,5-trisphosphate receptor (IP(3)R), ryanodine receptor (RYR), and protein kinase C (PKC). SA in relatively high dose (or = 100 microg/ml) dilated both endothelium-intact and endothelium-denuded aortic rings precontracted by phenylephrine (PE) or KCl (each P0.01). SA inhibited extracellular Ca(2+) influx induced by PE or KCl (each P0.01) and had no activation effect on K(+) channels on vascular smooth muscle. The relaxant effect of SA partly depended on the activity of NO synthase but not on the activity of cyclooxygenase.Taken together, this study indicated that SA had dual effects on vascular tension in rat isolated thoracic aorta.

In vitro and in vivo studies have demonstrated that inhibition of phospholamban (PLB) expression in myocardium can restore left ventricular systolic function in failing heart. Ultrasound mediated microbubble destruction provides a new option for noninvasive gene transfer in heart. In this study, we transferred pAAV-antisense phospholamban (pAAV-asPLB) to the hearts of myocardial infarction (MI) mice, using ultrasound mediated microbubble destruction. Then we estimated the protein levels of PLB, Ser16-PLB and cardiac sarcoplasmic reticulum Ca(2+) ATPase (SERCA). The left ventricular ejection fraction (LVEF), fraction shortening (FS) and SERCA activity were measured as well. MI mice were generated by ligating the left anterior descending coronary artery. Microbubbles were prepared by sonicated perfluorocarbon gas with dextrose and albumin. A mixture of pAAV-asPLB plasmid and microbubble was injected via tail vein while the heart was simultaneously exposed to ultrasound via transthoracic insonation. Three weeks later, LVEF (48.2+/-5.18% vs 39.1+/-5.38%, p0.05), FS (19.6+/-2.59% vs 16.0+/-2.29%, p0.05), SERCA activity (3.00+/-0.29 vs 2.12+/-0.30, p0.05) and Ser16-PLB protein level (0.8+/-0.25 vs 0.46+/-0.18, p0.05) were increased while PLB protein level (1.45+/-0.38 vs 2.05+/-0.31, p0.05) was decreased compared with the MI mice with saline injection. The above parameters in MI mice with only pAAV-asPLB plasmid injection or pAAV-asPLB plasmid combined with ultrasound alone were not significantly improved. pAAV-LacZ was used as a reporter gene to determine the efficiency and localization of transfection. The expression of beta-galactosidase was not found in liver, lung and brain, but found only in tubular epithelial cells of kidney and found in heart. These results confirm that asPLB gene transfection can be achieved by ultrasound mediated microbubble destruction with organ specificity. The effective transfection can partly restore heart function in MI mice.

Cyclophosphamide has a role of decreasing high-sensitivity C-reactive protein in the treatment of autoimmune disorders. The effect of cyclophosphasmide on high-sensitivity C-reactive protein was investigated in myocardial ischemia/reperfusion rat.Open-chest rats were submitted to 30 minutes of ischemia and followed for 3, 12, or 24 hours of reperfusion. All 72 rats survived and were divided into sham, ischemia/reperfusion (I/R) and cyclophosphamide groups, and each group included 3 time-point subgroups (3, 12, and 24 hours; n = 8 for each subgroup). Cyclophosphamide (0.75 g/m(2)) or saline was intraperitoneally administrated in the cyclophosphamide or I/R group. A polyethylene tube was inserted into the left ventricular cavity to detect left ventricular systolic pressure, left ventricular end-diastolic pressure, and maximum rate of rise or fall of left ventricular pressure. In the end, blood was collected for detection of high-sensitivity C-reactive protein, and hearts were harvested for histopathologic assessment and infarct size determination.Compared with the I/R group, rats treated with cyclophosphamide showed a significant recovery in myocardial function with improved left ventricular systolic pressure (88.27 +/- 3.78 vs 68.62 +/- 3.78 mm Hg at 3 hours, 92.04 +/- 3.77 vs 63.74 +/- 4.87 mm Hg at 12 hours, and 90.41 +/- 3.98 vs 64.21 +/- 4.88 mm Hg at 24 hours; P.05, respectively). Left ventricular end-diastolic pressure and maximum rate of rise or fall of left ventricular pressure also had similar trends. Infarct size was reduced (26.1% +/- 0.4% vs 40.4% +/- 0.4% at 3 hours, 21.6% +/- 0.4% vs 49.9% +/- 0.4% at 12 hours, and 21.6% +/- 0.4% vs 40.0% +/- 0.4% at 24 hours; P.01, respectively). Histopathologic damage score was attenuated (1.83 +/- 0.14 vs 2.17 +/- 0.14 at 3 hours, 2.33 +/- 0.14 vs 3.17 +/- 0.14 at 12 hours, and 2.83 +/- 0.14 vs 3.83 +/- 0.14 at 24 hours; P.01, respectively). Plasma high-sensitivity C-reactive protein concentration was significantly reduced (29.28 +/- 0.51 vs 32.26 +/- 0.51 ng/mL at 3 hours, 29.06 +/- 0.50 vs 31.8 +/- 0.51 ng/mL at 12 hours, and 28.61 +/- 0.51 vs 31.86 +/- 0.51 ng/mL at 24 h; P.01, respectively).Cyclophosphamide protects myocardial ischemia/reperfusion injury in the rat with a decrease in plasma concentration of high-sensitivity C-reactive protein.

Dobutamine stress echocardiography (DSE) is an established method of detecting myocardial ischemia. Its diagnostic accuracy solely depends on wall motion assessment. Clear visibility of the left ventricular endocardium is essential for reliable assessment of a wall motion abnormality. However, incremental benefits of contrast DSE for the detection of coronary artery disease (CAD) have not been demonstrated in overweight or obese patients.The purpose of the present study was to test the incremental benefits of contrast DSE in detecting CAD in overweight or obese patients.Sixty-two overweight or obese patients (body mass index 26 kg/m(2) to 33 kg/m(2)) underwent DSE with or without contrast and coronary angiography. Contrast-enhanced images were achieved at rest and during peak DSE after administration of SonoVue (Bracco Diagnostics Inc, Italy) or Optison (Mallinckrodt, USA). The endocardial border resolution for each myocardial segment was graded as 0, 1 or 2. A total of 992 segments from 62 subjects were analyzed. The results of DSE with or without contrast were compared with the findings on angiography.The differences in the score grading between the two groups with or without contrast, at rest and during peak DSE were statistically significant (P0.001). The sensitivity, specificity and accuracy of contrast DSE in detecting CAD, compared with the studies without contrast, were improved (82% versus 70%, 78% versus 67% and 81% versus 69%, respectively).SonoVue and Optison can enhance left ventricular endocardial border delineation in overweight or obese patients, optimizing the evaluation of wall motion both at rest and during peak stress. This increases the diagnostic value of DSE in detecting CAD.

Background Genotype–phenotype studies have suggested that some mutations of genes encoding various components of the cardiac sarcomere cause hypertrophic cardiomyopathy (HCM) and are associated with the prognosis of patients with HCM. The aims of this study were to investigate the gene mutations of exons in the cardiac beta myosin heavy chain (MYH7) gene, the troponin T (TNNT2) gene, and the brain natriuretic peptide (BNP) gene, as well as to assess the effect of these mutations on the clinical features of Chinese patients with HCM. Methods Five unrelated Chinese families with HCM were studied. Exons 3 and 18 in the MYH7 gene, exon 9 in the TNNT2 gene, and all three exons in the BNP gene were screened with the polymerase chain reaction (PCR) for genomic DNA amplification. Further study included purification of PCR products and direct sequencing of PCR fragments by fluorescent end labeling. Results A C-to-T transition in codon 26 of exon 3 in the MYH7 gene was found in one family (including four patients and five carriers), resulting in an amino acid substitution of valine (Val) for alanine (Ala). The Ala26Val mutation was of incomplete dominance (penetrance 44%). This mutation was not seen in the other four families or in the control group. Moreover, the association between the gene mutations of exon 18 in MYH7, of exon 9 of TNNT2, and of all three exons in BNP and HCM was not found in the populations we studied. Conclusions The missense mutation Ala26Val found in this one Chinese family was associated with a mild phenotype of HCM. The genetic and phenotypic heterogeneity of HCM exists in the Chinese population. It suggests that genetic and environmental factors may be involved in the pathogenesis of HCM.