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Bicuspid aortic valve (BAV) is the most common form of congenital cardiovascular defect in humans worldwide and is responsible for substantial morbidity and mortality. Accumulating evidence has demonstated that genetic risk factors are involved in the pathogenesis of BAV. However, BAV is genetically heterogeneous and the genetic basis underlying BAV in a large number of patients remains unknown. In the present study, the coding regions and splice junction sites of the GATA5 gene, which codes for a zinc-finger transcription factor crucial for the normal development of the aortic valve, was sequenced initially in 110 unrelated patients with BAV. The available relatives of the mutation carriers and 200 unrelated healthy individuals used as controls were subsequently genotyped for GATA5. The functional effect of the mutations was characterized by using a luciferase reporter assay system. As a result, two novel heterozygous GATA5 mutations, p.Y16D and p.T252P, were identified in two families with autosomal dominant inheritance of BAV, respectively. The variations were absent in 400 control chromosomes and the altered amino acids were completely conserved evolutionarily. Functional assays revealed that the two GATA5 mutants were associated with significantly reduced transcriptional activity compared with their wild-type counterpart. To the best of our knowledge, this is the first study on the association of GATA5 loss-of-function mutations with enhanced susceptibility to BAV, providing novel insight into the molecular mechanism involved in human BAV and suggesting a potential role for the early prophylaxis and personalized treatment of this common congenital heart disease.

Congenital heart disease (CHD) is the most common form of developmental malformation and is the leading noninfectious cause of infant mortality. Emerging evidence indicates that genetic defects are involved in the pathogenesis of CHD. Nevertheless, CHD is genetically heterogeneous, and the molecular basis for CHD in a majority of patients remains unknown. In this study, the whole coding region of GATA6, a gene encoding a zinc-finger transcription factor crucial for normal cardiogenesis, was sequenced in 380 unrelated patients with CHD. The relatives of the index patients harboring the identified mutations and 200 unrelated control individuals were subsequently genotyped. The functional effect of the mutations was characterized using a luciferase reporter assay system. As a result, two novel heterozygous GATA6 mutations, p.D404Y and p.E460X, were identified in two families with ventricular septal defect and tetralogy of Fallot, respectively. The mutations co-segregated with CHD in the families with complete penetrance, and were absent in 400 control chromosomes. Functional analysis demonstrated that the mutated GATA6 proteins were associated with significantly decreased transactivational activity in comparison with their wild-type counterpart. These findings provide novel insight into the molecular mechanism implicated in CHD, suggesting potential implications for the early prophylaxis and personalized treatment of CHD.

Summary Background Ventricular septal defect (VSD) is the most prevalent type of congenital heart disease and is a major cause of substantial morbidity and mortality in infants. Accumulating evidence implicates genetic defects, especially in cardiac transcription factors, in the pathogenesis of VSD. However, VSD is genetically heterogeneous and the genetic determinants for VSD in most patients remain to be identified. Material/Methods A cohort of 230 unrelated patients with congenital VSD was included in the investigation. A total of 200 unrelated ethnically matched healthy individuals were recruited as controls. The entire coding region of GATA4, a gene encoding a zinc-finger transcription factor essential for normal cardiac morphogenesis, was sequenced initially in 230 unrelated VSD patients. The available relatives of the mutation carriers and 200 control subjects were subsequently genotyped for the presence of identified mutations. Results Four heterozygous missense GATA4 mutations of p.Q55R, p.G96R, p.N197S, and p.K404R were identified in 4 unrelated patients with VSD. These mutations were not detected in 200 control individuals nor described in the human SNP database. Genetic analysis of the relatives of the mutation carriers showed that in each family the mutation co-segregated with VSD. Conclusions These findings expand the mutation spectrum of GATA4 linked to VSD and provide new insight into the molecular etiology responsible for VSD, suggesting potential implications for the genetic diagnosis and gene-specific therapy for VSD.

This study established a simple method of specifically detecting Salmonella species by amplifying fimW gene, which was involved in regulating Salmonella type I fimbriae expression. A pair of primers was designed to target and discriminate the 68 Salmonella strains of 23 Salmonella serovars available to us from 12 non-Salmonella strains of five different kinds of bacteria by polymerase chain reaction (PCR) amplification. Results showed that specific DNA fragment with an expected size of 477 bp was successfully amplified from all Salmonella serovars, while no target band was detected in non-Salmonella species. The sensitivity of this PCR-amplifying system reached to 1 pg DNA chromosome and 10(2) cfu of Salmonella enteritis strain CMCC(B) 50336. The above results demonstrated the method as a simple, sensitive, and specific way for Salmonella detection.

To investigate protective effects of pyruvate-enriched peritoneal dialysis solution (P-PDS), compared with lactate-PDS (L-PDS), on the intestinal mucosal barrier in peritoneal resuscitation (PR) from severe hemorrhagic shock (HS) in rats.Fifty male SD rats were randomly divided into five groups (n = 10): group sham, group control (HS without fluid resuscitation), group intravenous resuscitation (IVR) (HS with IVR only), group L-PDS (HS with i.v. infusion plus PR with L-PDS), and group P-PDS (HS with i.v. infusion plus PR with P-PDS). HS was induced by hemorrhage with mean arterial pressure 40 mm Hg for 60 min. In three groups with fluid rehydration, IVR included shed blood and dl-lactate Ringer solution equal to two times the volume of shed blood during 60 min; in two groups with PR, 20 mL of L-PDS, or P-PDS were infused when i.v. infusion started after HS into the peritoneal cavity in 20 min, respectively. Blood samples were taken for determinations of pH, base excess, PaCO2, PaO2, and D-LA 60 min post fluid resuscitation. After rats were sacrificed, a segment of intestine was harvested for the detection of expressions of intestinal barrier proteins: zonula occludens-1 (ZO-1) and phosphorylated vasodilator-stimulated phosphoprotein (p-VASP) by Western blot and immunohistochemistry. Intestinal morphologic alterations were also observed.Blood pH, base excess, and PaO2 were higher, whereas PaCO2 and D-LA were lower in group P-PDS than in other three HS groups (P0.05 and P0.01, respectively). Severe acidosis was nearly corrected in group P-PDS. Intestinal barrier proteins ZO-1 and p-VASP were significantly preserved in group P-PDS than in group L-PDS (P0.05) although they were improved in group L-PDS in comparison with other two HS groups (P0.05 or P0.01). Expressions of barrier proteins by Western blotting in group P-PDS were reversed to normal. The score of intestinal epithelial damage index was reduced in group L-PDS, compared with other two HS groups (P0.05), however, it was significantly lower in group P-PDS than in group L-PDS (P0.05).Pyruvate was superior to lactate in PDS in the correction of severe acidosis with PR. P-PDS was more preservative of expressions of intestinal ZO-1 and p-VASP and mucosal barrier function, compared with L-PDS in PR from severe HS in rats.

Ventricular septal defect (VSD) is the most prevalent type of congenital heart disease and a major cause for the significantly increased morbidity and mortality among infants. Aggregating evidence indicates that genetic defects are involved in the pathogenesis of congenital VSD. Nevertheless, VSD is genetically heterogeneous, and the genetic determinants for VSD in the majority of patients remain to be identified. In this study, the entire coding region of GATA4, a gene encoding a zinc finger transcription factor essential for normal cardiac morphogenesis, was sequenced in 160 unrelated patients with VSD. The available relatives of the index patient harboring the identified mutation and 200 unrelated control individuals were subsequently genotyped. The disease-causing potential of a sequence alteration was evaluated by MutationTaster, and the functional effect of the mutation was characterized using a luciferase reporter assay system. As a result, a novel heterozygous GATA4 variation, p.R43W, was identified in a proband with VSD, that was absent in control subjects. Genetic analysis of the family members of the variation carrier showed that the substitution co-segregated with VSD. The p.R43W variant was predicted to be a pathogenic mutation, and the functional analysis demonstrated that the GATA4 R43W mutant protein resulted in significantly decreased transcriptional activity compared with its wild-type counterpart. The findings expand the mutational spectrum of GATA4 linked to VSD and provide more insight into the molecular mechanism of VSD.

Atrial septal defect (ASD) is a common cardiovascular malformation and an important contributor to substantial morbidity and mortality. Increasing evidence demonstrates that mutated NKX2-5, a gene encoding a homeobox transcription factor crucial to cardiogenesis, is a significant genetic determinant for congenital ASD. Nevertheless, the genetic basis for ASD in a majority of ASD patients remains largely unknown. In the current study, the entire coding region of NKX2-5 was sequenced initially for 58 unrelated probands with familial ASD. The relatives of the probands harboring identified mutations and 200 unrelated control individuals were subsequently genotyped. Three novel heterozygous NKX2-5 mutations (p.P43GfsX59, p.C46 W, and p.S179F) were identified respectively in three families with autosomal dominantly inherited ASD. These mutations, absent in 200 control individuals, cosegregated with ASD in the families that had complete penetrance. The findings expand the spectrum of mutations in NKX2-5 linked to ASD and contribute to genetic counseling, clinical interventions, and prenatal prevention of ASD for individuals with genetic susceptibility.

Based on a room-temperature-operated THz fiber-scanning near-field imaging system, we demonstrate the capability of THz imaging for diagnosing human liver cancer. By THz near-field mapping of the absorption constants of liver tissues, the acquired images can clearly distinguish cancer from normal tissues fast, automatically, and correctly without pathological H&E staining examination. Accordingly, the studied THz imaging system has valuable potential applications in clinical cancer diagnosis. With the help of THz imaging, we can expect to economize the use of hospital and human resources.