Fluid shear stress differentially modulates expression of genes encoding basic fibroblast growth factor and platelet-derived growth factor B chain in vascular endothelium.

Fluid shear stress has been shown to be an important regulator of vascular structure and function through its effect on the endothelial cell. We have explored the effect of shear stress on the expression of the heparin-binding growth factors platelet-derived growth factor B chain (PDGF-B) and basic fibroblast growth factor (bFGF) in bovine aortic endothelial cells using a purpose-built cone-plate viscometer. Using morphometric analysis, we have mimicked the endothelial cell shape changes encountered in vivo in response to shear stress and correlated these with changes in gene expression. Steady laminar shear stress of 15 and 36 dyn/cm2 both resulted in endothelial cell shape change, but the higher shear stress induced greater and more uniform alignment in the direction of flow and nuclear protrusion after 24 h. Steady laminar shear stress of both 15 and 36 dyn/cm2 induced a significant 3.9- and 4.2-fold decrease, respectively, in PDGF-B mRNA at 9 h. In contrast, steady laminar shear of 15 dyn/cm2 induced a mild and transient 1.5-fold increase in bFGF mRNA while shear of 36 dyn/cm2 induced a significant 4.8-fold increase at 6 h of shear which remained at 2.9-fold at 9 h. Pulsatile and turbulent shear stress showed the same effect as steady laminar shear stress (all at 15 dyn/cm2 time-average magnitude) on PDGF-B and bFGF mRNA content. Cyclic stretch (20% strain, 20/min) of cells grown on silicone substrate did not significantly affect either PDGF-B or bFGF mRNA levels. These results suggest that expression of each peptide growth factor gene is differentially regulated by fluid shear stress in the vascular endothelial cell. These results may have implications on vascular structure and function in response to hemodynamic forces and present a model for the study of transduction of mechanical stimuli into altered gene expression.     

Laparoscopic reduction and repair of a strangulated interparietal inguinal hernia

An interparietal hernia is defined as a hernia in which the hernial sac lies between the tissue layers comprising the abdominal wall. A strangulated interparietal inguinal hernia without an external bulge is a rare cause of an acute abdomen and difficult to diagnose preoperatively. We report a patient with a history of a right inguinal hernia who presented with abdominal pain without inguinal bulging. An interparietal (preperitoneal) inguinal hernia was diagnosed and treated by laparoscopic reduction and a transabdominal preperitoneal hernia repair. This is the first case report of an interparietal inguinal hernia managed entirely laparoscopically. Although the laparoscopic approach is not considered standard treatment for strangulated intestinal obstruction, it may be worth considering, especially for patients with uncertain etiology, because of its decreased invasiveness compared to open exploration.     

Molecular basis of antithrombin deficiency in four Japanese patients with antithrombin gene abnormalities including two novel mutations

We analyzed the antithrombin (AT) gene in four unrelated Japanese patients with an AT deficiency, and individually identified four distinct mutations in the heterozygous state. There were two novel mutations, 2417delT leading to a frameshift with a premature termination at amino acid -3 (FS-3Stop) and C2640T resulting in a missense mutation (Ala59Val). Previously reported mutations, T5342C (Ser116Pro) and T72C (Met-32Thr), were also found in the other two patients. To understand the molecular basis responsible for the AT deficiency in these patients, in vitro expression experiments were performed using HEK293 cells transfected with either wild type or respective mutant AT expression vector. We found that -3Stop-AT and -32Thr-AT were not secreted into the culture media, whereas 116Pro-AT and 59Val-AT were secreted normally. We further studied the heparin cofactor activity and the binding to heparin of each recombinant AT molecule. Ser116Pro mutation significantly impaired the binding affinity to heparin resulting in a reduced heparin cofactor activity. In contrast, we found that Ala59Val mutant AT unexpectedly showed a normal affinity to heparin, but severely impaired the heparin cofactor activity. Our findings suggested that FS-3Stop and Met-32Thr mutations are responsible for type I AT deficiency, whereas Ser116Pro and Ala59Val mutations contribute to type II AT deficiency, confirming that there were diverse molecular mechanisms of AT deficiency depend upon discrete AT gene abnormalities as reported previously.     

Reception and Transmission of Taste Information in Type II and Type III Taste Bud Cells

Gustatory information processing begins with taste bud cells, which are activated by sapid molecules via specific taste receptors and transmit their signals to gustatory afferent fibers. Taste bud cells are morphologically classified into 4 groups (Type I – IV cells), two of which are involved in gustatory signaling. Type II cells express sweet, bitter, and umami taste receptors and transduction components and respond best to sweet, bitter, or umami stimuli, suggesting that sweet, bitter, and umami tastes are detected by different sets of Type II cells. Type III cells express putative sour taste receptors and respond to sour or multiple taste stimuli, indicating that sour tastes are mediated by Type III cells. These data suggest that each taste quality could be discriminated among taste bud cells. Type II cells do not possess a conventional synaptic structure but they release ATP in response to taste stimuli. Type III cells have a synaptic structure and they release serotonin and norepinephrine but not ATP. Therefore, each taste cell may use distinct mechanisms and transmitters for signal transmission to gustatory nerve fibers.     

Differential regulation of DEC2 among hypoxia-inducible genes in endometrial carcinomas

In this study, we demonstrate an important role of activation of the hypoxia-inducible factor-1 (HIF-1) pathway in endometrial carcinogenesis and tumor phenotype development of endometrial carcinoma, and suggest a unique role of the HIF-1-target gene, differentiated embryo chondrocyte 2 (DEC2), in carcinogenesis. Hypoxia caused an increase in HIF-1alpha protein expression in 4 endometrial carcinoma cell lines. The expressions of its 5 target genes - DEC1, DEC2, carbonic anhydrase-9 (CA9), vascular endothelial growth factor (VEGF), and solute carrier family 2, member 1 (SLC2A1) - also reactively increased in most of the cell lines, except for DEC2 in the SNG-M cells. The expression levels of DEC2, CA9, and SLC2A1 were significantly higher in the 4 atypical hyperplasia tissues and 82 endometrial carcinomas compared with those in the 21 normal endometria. Clinicopathological analyses of carcinoma patients revealed a significant correlation of the VEGF and SLC2A1 expression with the status of lymph-vascular involvement and lymph node metastasis. The expression levels of CA9 and VEGF were significantly higher in the tumors of post- as opposed to pre-menopausal patients. The SLC2A1 expression was also related to the FIGO stage, but the DEC2 expression was inversely related to the FIGO grade. The activation of the HIF-1 pathway could be related to endometrial carcinogenesis, and the component, DEC2, could have different expression-regulatory mechanisms and unique roles in carcinogenesis.     

Serial quantitative angiographic study of target lumen enlargement after drug-coated balloon angioplasty for native coronary artery disease

Background

Target lumen enlargement (TLE) or “late lumen enlargement” is often encountered after percutaneous coronary intervention (PCI) with drug-coated balloons (DCB). To date, the prognosis of coronary arterial lesions with or without TLE has not been clearly elucidated.

Aims

This study aimed to assess the long-term prognosis of coronary arterial lesions with or without TLE observed within 1 year (early TLE) after DCB angioplasty using serial quantitative angiographic follow-up.

Methods

One hundred and ninety-three consecutive patients (de novo coronary arterial lesions, 251) who underwent follow-up angiography within 1 year after DCB angioplasty (early follow-up, median: 6 months) were retrospectively evaluated. Of these, 97 patients (125 lesions) also underwent angiography more than 1 year after DCB angioplasty (late follow-up, median: 37 months). TLE was defined as an increase in minimal lumen diameter (MLD) after PCI at each follow-up.

Results

Early TLE was detected in 142 lesions (56.6%). Of these, 76 lesions were also evaluated at late follow-up. TLE persisted even at late follow-up in 67 of the 76 lesions (88.2%). An increase in MLD in early TLE (+) lesions was observed in the period between post-PCI and early follow-up (1.84 ± 0.06 vs. 2.12 ± 0.07 mm, p < 0.001) but not between early and late follow-up (2.12 ± 0.07 vs. 2.16 ± 0.07 mm, p = 0.74). In contrast, 49 of 109 lesions without early TLE were evaluated at late follow-up, of which 28 lesions (57.1%) showed TLE at late follow-up. The MLD of early TLE (−) lesions (n = 49) significantly increased from early (1.63 ± 0.061 mm) to late follow-up (1.84 ± 0.06 mm) (p < 0.001). No aneurysms were found in any of these cases.

Conclusion

Early TLE was observed in more than half of the lesions, with the majority remaining at late follow-up. Alternatively, half of the lesions without early TLE showed late TLE, occurring biphasically after DCB angioplasty.     

Clinical and EEG analysis of initial status epilepticus during infancy in patients with mesial temporal lobe epilepsy

This study investigated the clinical and EEG characteristics of initial status epilepticus (SE) during infancy in patients with mesial temporal lobe epilepsy (MTLE). The subjects were six patients who had been brought to our emergency clinic and treated for their initial SE between 1977 and 1988, and later developed MTLE. We reviewed the medical records and laboratory findings at the time of the initial SE, and the clinical evolution up to the development of MTLE. The six patients included four females and two males. The initial SE developed at ages ranging from 7 months to 2 years and 9 months with a mean of 1 year and 2 months. These episodes were characterized by an elevated temperature of more than 38 degrees C (4/6 cases), clusters of prolonged seizures during one episode of SE (4/6 cases), long-lasting SE (120-380 min, mean 227 min, 6/6 cases), postictal prolonged loss of consciousness (median 5 h, 6/6 cases), and the presence of Todd's paralysis (3/6 cases). The lateralization of the ictal or postictal EEGs of the SE in five of the six cases was identical to that of the hippocampal atrophy later confirmed by MRI. Follow-up EEG examinations at a 6 month interval demonstrated temporal spike discharges appearing only after the onset of complex partial seizures. Two patients, who had no fever at the initial SE, were characterized by a very early appearance of epileptic EEG abnormality and a short interval between the initial SE and the development of complex partial seizures, suggesting that the SE was the first epileptic manifestation. The result of this study showed that SE progressing to MTLE tends to have complicated clinical manifestations characterized by clusters of unilateral or generalized SE followed by prolonged postictal unconsciousness, generalized clinical manifestations despite lateralized ictal EEG discharges, and the Todd's paresis in addition to the prolonged seizure duration.     

Failure to confirm an association between <Emphasis Type="Italic">Epsin 4</Emphasis> and schizophrenia in a Japanese population

Previous studies suggested that genetic variations in the 5' region of Epsin 4, a gene encoding enthoprotin on chromosome 5q33, are associated with schizophrenia. However, conflicting results have also been reported. We examined the possible association in a Japanese sample of 354 patients and 365 controls. Seventeen polymorphisms of Epsin 4 [3 microsatellites and 14 single nucleotide polymorphisms (SNPs)] were selected. A microsatellite marker (D5S1403) demonstrated a significant difference in the allele frequency between patients and controls (uncorrected P = 0.04). However, there was no significant difference in the genotype or allele frequency between the two groups for the other microsatellites or SNPs. Haplotype-based analysis provided no evidence for an association. The positive result at D5S1403 no longer reached statistical significance when multiple testing was taken into consideration. Our results suggest that the examined region of Epsin 4 does not have a major influence on susceptibility to schizophrenia in Japanese.