Demographics and characteristics of endoscopic findings among COVID-19 patients with upper gastrointestinal bleeding in a single centre.

INTRODUCTION: Novel coronavirus 19 disease (COVID-19) pandemic poses healthcare providers challenges in the endoscopic suite. It is unclear whether it affects the endoscopic manifestations of upper gastrointestinal (GI) bleeding. This retrospective study was done to review demographic data, site of lesions and need of interventions for those lesions. MATERIALS AND METHODS: Oesophagoduodenoscopy (OGDS) reports of COVID-19 patients with indication of upper GI bleeding from March 2021 to April 2022 were reviewed. Data of 35 patients were then analysed. RESULTS: Of the 35 patients, 8.6% (n = 3) were female and 91.4% (n = 32) were males. A total of 31.4% (n = 11) were below 50 years and 68.6% (n = 24) were 50 and above. 34.3% (n = 12) with lesions requiring endoscopic intervention, 34.3% (n = 12) with lesions not requiring endoscopic intervention, 31.4% (n = 11) has no significant stigmata of recent haemorrhage. Among subgroup requiring endoscopic intervention, 50% (n = 6) are non-variceal bleeding (NVUIB), and 50% (n = 6) are variceal bleeding (VUGIB). Among NVUGIB, 16.7% (n = 1) is gastric and duodenal angiodysplasia requiring argon plasma coagulation, 50% (n = 3) are duodenal F2A ulcer requiring thermoablation, 16.7% (n = 1) is gastric F2A ulcer requiring hemoclip, and 16.6% (n = 1) is Cameron's ulcer requiring hemoclip. Among VUGIB, 100% (n = 6) are oesophageal varices requiring endoscopic variceal banding (EVL). CONCLUSIONS: Lower proportion of NVUGIB among COVID-19 patients raises hypothesis on whether prothrombotic state of COVID-19 is a protective factor of NVUGIB. Studies with larger sample size are needed to establish significance.

[Normative values of cervical sagittal alignment according to the whole spine balance: Based on 126 asymptomatic Chinese young adults].

OBJECTIVE: To explore the normal distribution of cervical sagittal alignment and the relationship between cervical alignment and global spine balance in asymptomatic young adults. METHODS: A cohort of 272 asymptomatic Chinese adults (including 161 males and 111 females, with an average age of (23.2±4.4) years, ranging from 18 to 45 years) were prospectively recruited from November 2011 to December 2014. The C0-C2 angle, disk angles from C2-C3 to C6-C7, vertebral angles from C3 to C7, T1 slope, thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), C2-C7 sagittal vertical axis (C2-C7SVA), center of gravity of head to C7SVA (CGH-C7SVA), C7-S1SVA were measured and statistically analyzed. All the subjects were categorized with the Roussouly classification and the cervical morphologies were evaluated as lordotic, straight, sigmoid or kyphotic. Spinal sagittal alignment parameters were compared between different sexes and Roussouly classifications with independent student t test, analysis of variance (ANOVA) or Chi-square test. Correlations between cervical sagittal alignment and global spine sagittal alignment were calculated using the Pearson and Spearman correlation coefficient. Linear regression analysis was performed. RESULTS: Sixty-seven males and 59 females aged from 18 to 30 years old were included in the study. The mean value of C0-C7 was 26.0°±12.8°, composed of 15.2°±6.7° for C0-C2, 9.1°±12.1° for sum of disk angles from C2-C3 to C6-C7, and 1.4°±10.2° for sum of vertebral angles from C3 to C7. C2-C7SVA [(18.6±7.9) mm] and CGH-C7SVA [(22.9±12.3) mm]were offset ideally by C7-S1SVA [(-21.6±31.0) mm]. Males had a larger T1 slope (P < 0.05) and accordingly, a larger cervical lordosis C2-C7 (P < 0.01) and C0-C7 angle (P < 0.01) than females. Males had a smaller C7-S1SVA (P < 0.01) and accordingly, a smaller CGH-C7SVA (P=0.165) than females. Significant difference was found between cervical alignment of different Roussouly types (P < 0.01). In general, a larger LL was consistent with a set of larger TK, C2-C7angle, C0-C7 angle, and vice versa. There was no significant correlation between cervical morphology and the Roussouly classification (Chi-square=10.548, P=0.308). There was significant correlation between cervical alignment and T1 slope (P < 0.01), TK (P < 0.01). There was significant correlation between adjacent segmental angles from T1 slope up to C0-C2 angle (P < 0.05). CONCLUSION: Normative values of each vertebral angle and disk angle were established. The cervical lordosis occurred mainly at C0-C2 and disk levels, which was influenced by parameters of other parts of the spine, such as T1 slope, TK and the Roussouly classification. There was significant correlation between adjacent disk angles.

[Effect analysis of treating intracranial wide-neck bifurcation aneurysms through Woven EndoBridge].

Objective: To explore the clinical effect of Woven EndoBridge (WEB) in the treatment of wide-neck bifurcation aneurysms. Methods: The clinical and imaging data of 11 patients with intracranial wide-neck bifurcation aneurysms treated by WEB alone at Department of Neurosurgery of the Northern Theater General Hospital from September 2017 to May 2018, were retrospectively analyzed. The patients were 7 males and 4 females, aged (54±11) years (ranged from 31 to 66 years). The aneurysms of 5 patients were located in the anterior communicating artery, 3 in the top of the basilar artery, and 3 in the bifurcation of the middle cerebral artery. The intraoperative and postoperative conditions of the patients were recorded, and the degree of aneurysm embolization was evaluated by WEB embolization aneurysm occlusion scale (WOS). Results: The intraoperative WEB release of all the 11 patients was good, with 3 cases of WOS grade A, 1 of grade B and 7 of grade C, with no intraoperative acute complications occurring. The imaging follow-up was not carried out in 1 patient due to economic reason, and the clinical follow-up was good until 3 years after the operation; 10 patients were followed up by imaging for 6 months to 3 years, and no postoperative complications occurred in the target treatment area. Among the 2 patients with WOS grade A and 1 patient with grade B during operation, according to the postoperative follow-up, all were WOS grade A; among the 7 patients with WOS grade C during operation, 4 were still of grade C and 3 were of grade D according to the follow-up. Among the 3 patients with WOS grade D, 1 patient received secondary embolization due to poor recurrence morphology, unstable hemodynamics and high possibility of rupture of aneurysm, stent assisted coil embolization was adopted, with good immediate effect; the other 2 cases had recurrent aneurysms, but the aneurysms had good morphology and stable hemodynamics, therefore, clinical follow-up was continued and no secondary surgery was performed. No complications occurred in all these 11 patients. Conclusions: The operation of treating unruptured intracranial wide-neck bifurcation aneurysms with WEB device alone is simple, and there is no need for anticoagulation and antiplatelet treatment before and after the operation, the clinical effect is being good. WEB device provides a new treatment option for intracranial wide-neck bifurcation aneurysms.

Mesothelin-specific cell-based vaccine generates antigen-specific immunity and potent antitumor effects by combining with IL-12 immunomodulator.

Ovarian cancer is a gynecologic malignancy with a high mortality rate. In the present study, we developed a novel cell-based vaccine, Meso-VAX, to generate mesothelin antigen-specific immune responses and immunotherapy against ovarian cancer. Mesothelin, a secreted protein anchored at the cell membrane, has recently been identified as a potential new tumor antigen for ovarian cancer. In this study, mice vaccinated with Meso-VAX and adeno-associated virus (AAV)-IL-12 exhibited dramatic increases in the number of mesothelin-specific CD4(+) helper and CD8(+) cytotoxic T-cell precursors, higher titers of anti-mesothelin Abs and in vitro tumor killing activity, and all of these mice were tumor-free after 60 days of tumor challenge. In addition, a significant reduction in peritoneal tumors and longer survival were noted in the mice vaccinated with Meso-VAX combined with AAV-IL-12. CD4(+) helper and CD8(+) cytotoxic T lymphocytes were essential for the antitumor effect generated by Meso-VAX combined with AAV-IL-12. The post-vaccination sera of the mice vaccinated with Meso-VAX and AAV-IL-12 also showed mesothelin-specific complement-dependent cell-mediated cytotoxicity. Our results suggest that a Meso-VAX cell-based vaccine combined with AAV-IL-12 can generate antigen-specific immunological responses and antitumor effects on ovarian cancer.

Initial periodontal therapy for the treatment of gingival pregnancy tumor.

The purpose of this study was to evaluate the clinical efficacy of initial periodontal therapy in gingival pregnancy tumors. Thirty-nine patients diagnosed with gingival tumors of pregnancy between 2007 and 2015 were enrolled in this study. The patients received initial periodontal therapy, then supportive periodontal therapies at 3- to 6-month intervals. The patients underwent follow up for 6 months to 8 years after treatment. After plaque control, supragingival scaling, and root planning, the tumors in 25 patients were gradually eliminated without the necessity of surgery. In 3 patients, tumors <5 mm in size disappeared in a mean time of 3.6 months, 4 patients with tumors 5-10 mm disappeared in a time of 7.5 months, 11 patients with tumors 10-15 mm disappeared in 10.2 months, 6 patients with tumors 15-20 mm disappeared in 15 months, and one patient with a tumor >20 mm disappeared in 20 months. No recurrence of gingival pregnancy tumors was noted during subsequent follow-up. Initial periodontal therapy combined with oral hygiene maintenance is efficacious in treating gingival pregnancy tumors of patients with normal hormone levels, which can potentially serve as an option to avoid surgery.

Astrocytic Cx 43 and Cx 40 in the mouse hippocampus during and after pilocarpine-induced status epilepticus.

Astrocytes have now been well accepted to play important roles in epileptogenesis by controlling gliotransmitter release and neuronal excitability, contributing to blood-brain barrier dysfunction and involving in brain inflammation. Recent studies indicate that abnormal expression of gap junction protein connexin (Cx) may also be a contributing factor for seizure generation. To further address this issue, we investigated the progressive changes of Cx 43 and Cx 40 in the mouse hippocampus at 4 h, 1 day, 1 week and 2 months during and after pilocarpine-induced status epilepticus (PISE). The co-localization of Cx 43 and Cx 40 with glial fibrillary acidic protein (GFAP) was also examined. We observed that Cx 43 and Cx 40 protein expression remained unaltered at 4 h during and at 1 day (acute stage) after PISE. However, their expression was significantly increased in CA1 and CA3 areas and in the dentate gyrus at 1 week (latent stage) and 2 months (chronic stage) after PISE. Double immunofluorescence labeling indicated the localization of Cx 43 and Cx 40 in astrocytes. Combined with progressive neuronal loss in the mouse hippocampus, our results suggest that the increase in gap junctions in the neuronoglial syncytium of reactive astrocytes may be implicated in synchronization of hippocampal hyperactivity leading to neuronal loss and epileptogenesis.

Nuclear localization of Ca(v)2.2 and its distribution in the mouse central nervous system, and changes in the hippocampus during and after pilocarpine-induced status epilepticus.

AIMS: To investigate the subcellular localization of Ca(v)2.2 calcium channel in the mouse central nervous system (CNS), and changes of Ca(v)2.2 at acute and chronic stages during and after pilocarpine-induced status epilepticus (PISE), in order to find out the roles it may play in epileptogenesis. METHODS: Combined immunocytochemistry at both light and electron microscopic levels with real-time reverse transcription polymerase chain reaction (RT-PCR), cell transfection approach were used in this study. RESULTS: N-type calcium channel Ca(v)2.2 subunit was distributed in different regions of the mouse CNS. It was mainly localized in the nuclei in different types of neurones and in astrocytes. At acute stages during and after PISE, Ca(v)2.2 expression decreased in the stratum pyramidale of CA3 area and in the stratum granulosum of the dentate gyrus, but increased in the stratum lucidum of CA3 area and in the hilus of the dentate gyrus. At chronic stage at 2 months after PISE, increased expression of Ca(v)2.2 in both the strata granulosum and molecular of the dentate gyrus was observed. CONCLUSIONS: Ca(v)2.2 is a nuclear protein in neurones and astrocytes in the mouse CNS. Its translocation occurs at acute stages during and after PISE. The increased expression of Ca(v)2.2 in both the strata granulosum and moleculare of the dentate gyrus at chronic stage at 2 months after PISE may be involved in the occurrence of spontaneously recurrent seizures.

Clinical significance of tumor mutation burden and DNA damage repair in advanced stage non-small cell lung cancer patients.

OBJECTIVE: This study aimed to investigate the impact of tumor mutational burden (TMB) and DNA damage repair (DDR) gene alteration on overall survival (OS) in advanced non-small cell lung cancer (NSCLC) patients. PATIENTS AND METHODS: A DNA library of cancer cells from 67 NSCLC patients in stages III-IV was constructed for next-generation sequencing (NGS). Geneseeq422 probes were used for hybridization enrichment. The target-enriched library was sequenced on HiSeqNGS platforms, and we analyzed the relevant signaling pathways. Then, we correlated the OS of the patients with TMB and DDR mutations. RESULTS: Many significant alterations were found, including in the EGFR, p53, KRAS, RB1, ERBB2, NF1, DNMT3A, ALK, MYC, PIK3CA, ROS1, BRAF, ARID1A, PTEN, CDKN2A, and FGF19 genes. We also identified many mutations in the genes relevant to the DDR pathway. Interestingly, we found that the TMB of patients with DDR gene mutations was dramatically higher than that in the DDR wild-type (WT). Univariable analysis showed that DNMT3A, RB1, DDR pathway-related gene mutations, and TMB were critical factors for the effects on OS. Multivariable analysis confirmed that DNMT3A and mutations in the DDR pathway-related genes were important for predicting OS. CONCLUSIONS: Multiple mutations in the genes of the DDR pathway caused higher TMB levels, which resulted in longer OS. By contrast, OS was significantly longer in patients with non-DNMT3A mutations than in those with DNMT3A variants. DNMT3A alteration in NSCLC patients led to poor outcomes.

CCR3, CCR2A and macrophage inflammatory protein (MIP)-1a, monocyte chemotactic protein-1 (MCP-1) in the mouse hippocampus during and after pilocarpine-induced status epilepticus (PISE) .

AIMS: To investigate protein and gene expressions of chemokine subtypes CCR3, CCR2A and their respective ligands macrophage inflammatory protein 1-alpha (MIP-1alpha), monocyte chemotactic protein-1 (MCP-1) in the normal mouse central nervous system (CNS) and in the hippocampus at different time points during and after pilocarpine-induced status epilepticus (PISE). METHODS: CCR3 and MIP-1alpha protein expressions were mapped in the mouse CNS. The protein and gene expressions of CCR3 and CCR2A and their respective ligands MIP-1alpha, MCP-1 in the hippocampus were studies by immunocytochemical and quantitative real-time RT-PCR during and after PISE. RESULTS: CCR3 and MIP-1alpha gene expression and immunopositive neurones were broadly distributed in the CNS. CCR3 and CCA2A gene and their protein expression were downregulated in the hippocampus at 1 h during PISE. The protein expression of MIP-1alpha, MCP-1 decreased but gene expression increased at 2 h during PISE. In the hilus of the dentate gyrus, significant reduction of the numbers of CCR3, CCR2A, MCP-1 immunopositive neurones occurred from 1 h during to 2 months after PISE, but the number of MIP-1alpha neurones reduced from 2 h during to 2 months after PISE. Induced expression of CCR3 at 1 week, CCR2A, MCP-1 or MIP-1alpha at 1 week and 2 months after PISE was found in reactive astrocytes. MCP-1 was also demonstrated in the blood vessels of the hippocampus at 2 months after PISE. CONCLUSIONS: CCR3 and MIP-1alpha may play important functional roles in the mouse brain. The downregulation of CCR3, CCR2A, MIP-1alpha and MCP-1 in the hippocampal neurones at the acute stage during and after PISE may weaken the neuroprotective mechanisms. However, induced expression of MCP-1 in hippocampal blood vessel may be related to changes in permeability of the blood-brain barrier during epileptogenesis.

miR-212-3p reduced proliferation, and promoted apoptosis of fibroblast-like synoviocytes via down-regulating SOX5 in rheumatoid arthritis.

OBJECTIVE: Several microRNAs have been reported to contribute the progression of rheumatoid arthritis (RA) due to the ectopic expression of miRNAs in fibroblast-like synoviocytes (FLS). However, the function of miR-212-3p in RA still has not been mentioned before. PATIENTS AND METHODS: We obtained serum, synovial tissues, and FLS samples from RA patients and normal donors. Quantitative Real-time polymerase chain reaction (qRT-PCR) was used to analysis the expression level of miR-212-3p. By using miR-212-3p mimics and inhibitors, we detected the effects of miR-212-3p on cell proliferation, cell cycle, and apoptosis in RA-FLS. Dual-luciferase and Western-blot were employed to verify the target of miR-212-3p. In addition, we over-expressed the SOX5 in miR-212-3p mimics treatment FLS to emphasize our results. RESULTS: The level of miR-212-3p in serum, synovial tissues, and FLS from RA patients was lower than these in relative normal group. Up-regulation of miR-212-3p inhibited cell proliferation, promoted cell apoptosis; however, knockdown of miR-212-3p promoted cell growth but reduced cell apoptotic rate. Furthermore, we found SOX5 as a direct target of miR-212-3p in RA-FLS and up-regulation of SOX5 reversed the effects of miR-212-3p over-expression. CONCLUSIONS: miR-212-3p could reduce cell proliferation and promoted cell apoptosis of RA-FLS via repressing SOX5, which may provide a new biological target for RA treatment.

Early diagnostic role of PSA combined miR-155 detection in prostate cancer.

OBJECTIVE: As a kind of malignant tumor in the male genitourinary system, prostate cancer exhibits significantly increased occurrence. Prostate-specific antigen (PSA) expression can be seen in the prostate cancer, prostatitis, and other diseases, therefore, lack of diagnostic specificity. The miR-155 expression is abnormally increased in the tumors. Therefore, this study aims to explore the clinical significance of PSA combined miR-155 detection in the early diagnosis of prostate cancer. PATIENTS AND METHODS: A total of 86 patients diagnosed with prostate cancer were enrolled in this study. PSA and miR-155 gene expression in tumor tissue were detected by using Real-time PCR. The serum levels of PSA were measured by using enzyme-linked immunosorbent assay (ELISA). The correlation of PSA and miR-155 expression with age, body mass index (BMI), tumor volume, tumor-node-metastasis (TNM) stage, lymph node metastasis (LNM), and other clinicopathological features were analyzed, respectively. RESULTS: Serum PSA expression and PSA gene in tumor tissue were significantly higher compared to that in adjacent tissues (p<0.05). PSA gene and protein increased significantly with the clinical stage of TNM and decreased following the increase of grade (p<0.05). The miR-155 level was significantly elevated in the tumor tissue compared with para-carcinoma tissue (p<0.05). PSA and miR-155 expressions were positively correlated with TNM stage, tumor volume, and LNM, and negatively correlated with grade (p<0.05). CONCLUSIONS: PSA and miR-155 were closely related to the clinicopathological features of prostate cancer. Combined detection is helpful for the early diagnosis of prostate cancer.

Diagnostic and prognostic implications of serum miR-101 in osteosarcoma.

Blood-circulating microRNAs (miRNAs) have been reported to be used as potential biomarkers in various cancers. MiR-101 has been found to act as a tumor suppressor in many tumor types, but little is known for osteosarcoma. The purpose of this study was to investigate miR-101 expression in osteosarcoma patients and assess its correlation with clinical features and prognosis. Serum samples from 152 osteosarcoma patients and 70 healthy controls were detected using quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The data showed that miR-101 expression levels were remarkably underexpressed in serum samples from osteosarcoma patients compared to controls, and the post-treatment serum miR-101 expression was significantly higher than that in the pre-treatment expression. Low serum miR-101 expression was positively associated with advanced clinical stage and distant metastasis. Receiver operating characteristic (ROC) curve analysis showed that serum miR-101 could serve as a useful marker for osteosarcoma diagnosis, with a high sensitivity and specificity. Moreover, patients with high miR-101 expression had longer overall survival and recurrence free survival than those with low miR-101 expression. In addition, both univariate and multivariate analyses showed that serum miR-101 downregulation was associated with shorter overall survival and recurrence free survival. Our present results implicated serum miR-101 might be a useful biomarker for the clinical diagnosis and prognosis of osteosarcoma.

Calcium binding protein containing neurons in the gliotic mouse hippocampus with special reference to their afferents from the medial septum and the entorhinal cortex.

In CA1 area and the hilus of the dentate gyrus of the mouse hippocampus, drastic reduction of NeuN, calbindin, calretinin, or parvalbumin immunopositive neurons was shown at 3, 7 and 60 days after pilocarpine-induced status epilepticus. In gliotic CA1 area at 60 days, few dendritic branches of calcium binding protein immunopositive neurons could be found suggesting reorganization of the afferents of surviving calcium binding protein immunopositive neurons. Calbindin, calretinin, or parvalbumin and 5-bromo-2'-deoxyuridine (BrdU) double labeling showed that calcium binding protein immunopositive neurons in gliotic CA1 area at 60 days were surviving instead of newly generated neurons. Iontophoretic injection of Phaseolus vulgaris leucoagglutinin into the medial septum and the nucleus of the diagonal band of Broca or the lateral entorhinal cortex showed contacts between Phaseolus vulgaris leucoagglutinin immunopositive en passant and terminal boutons and surviving calcium binding protein immunopositive neurons in the hippocampus. The presence in the gliotic hippocampus of enlarged and/or aggregated bouton-like structures 60 days after pilocarpine-induced status epilepticus is indicative for the reorganization of connections between the hippocampal afferents and surviving hippocampal neurons. This reconstruction could be a factor in the ongoing epileptic activity in this model of mesial temporal lobe epilepsy.

Relation of electrolytes to blood pressure in men. The Yi people study.

The relations of sodium, potassium, calcium, and magnesium to blood pressure were investigated in four groups of men (119 high-mountain Yi farmers, 114 mountainside Yi farmers, 89 Yi migrants, and 97 Han people) with a wide range of electrolyte intake in Puge County, Sichuan Province, People's Republic of China. Electrolytes were measured in diet, serum, and urine. Sodium excretion was 73.9 mmol/24 hr in high-mountain Yi farmers, 117.9 mmol/24 hr in mountainside Yi farmers, 159.4 mmol/24 hr in Yi migrants, and 186.0 mmol/24 hr in the Han people. In ecological correlation analysis, dietary and urinary sodium were significantly and positively correlated with both systolic and diastolic pressure, whereas serum sodium showed no relation with blood pressure. In diet, serum, and urine, potassium was negatively related to systolic and diastolic pressure, whereas the sodium/potassium ratio showed a positive association. With regard to calcium, only urinary excretion was significantly and positively related to blood pressure. No relation was found between magnesium and blood pressure. Analyses at the individual level confirmed the results for sodium and potassium seen at the ecological level, but in addition, dietary calcium and magnesium were significantly and negatively correlated to both systolic and diastolic pressure, and urinary magnesium was inversely related to diastolic pressure. These relations persisted after controlling for age, body mass index (kg/m2), heart rate, alcohol, and total energy intake in multiple regression analysis performed separately for electrolytes in diet, serum, and urine. In multiple regression analysis, an increase in sodium intake of 100 mmol/day corresponded to an increase of 2.3 mm Hg systolic blood pressure and 1/8 mm Hg diastolic pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Urinary electrolytes and blood pressure in three Yi farmer populations, China.

The relation between blood pressure and urinary electrolytes, including sodium, potassium, calcium, and magnesium were examined in male farmers of the Yi nationality who live in three separate communities in Sichuan and Yunnan provinces in China, where the lifestyles, habits, and living conditions are very different. One of these three communities was unacculturated and had the lowest average blood pressure as well as the lowest prevalence rate of hypertension in China; one was acculturated and had the highest average blood pressure; and the third was moderately acculturated with its average blood pressure between the other two. Blood pressure was taken on each of 3 days and corresponding 24-hour urine specimens were collected to measure potassium, sodium, calcium, magnesium, urea nitrogen, and creatinine. Ecological and individual-based data correlation analyses were employed to study the relations among age, body mass index, some related indexes of electrolyte derivatives, and blood pressure. Multiple regression analyses were used to explore the relation of blood pressure to the above indexes, adjusted for age, body mass index, urea nitrogen and creatinine, and geographical differences. Statistically significant correlation analyses showed that systolic blood pressure was positively associated with sodium-creatinine, calcium-creatinine, sodium-potassium, calcium-magnesium, and urea nitrogen and creatinine ratios; negatively associated with potassium-creatinine and magnesium-creatinine ratios. The ridge regression analysis selected only calcium-magnesium ratio as a predictor of systolic blood pressure.

IS3 peptide-formed ion channels in rat skeletal muscle cell membranes.

A 22-mer peptide, identical to the primary sequence of domain I segment 3 (IS3) of rat brain sodium channel I, was synthesized. With the patch clamp cell-attached technique, single channel currents could be recorded from the patches of cultured rat myotube membranes when the patches were held at hyperpolarized potentials and the electrode solution contained NaCl and 1 microM IS3, indicating that IS3 incorporated into the membranes and formed ion channels. The single channel conductances of IS3 channels were distributed heterogeneously, but mainly in the range of 10-25 pS. There was a tendency that the mean open time and open probability of IS3 channels increased and the mean close time decreased with the increasing of hyperpolarized membrane potentials. IS3 channels are highly selective for Na+ and Li+ but not for Cl- and K+, similar to the authentic Na+ channels.

Effect of dietary electrolytes upon calcium excretion: the Yi People Study.

OBJECTIVE: To investigate the relations of dietary sodium, potassium, calcium and magnesium with urinary calcium excretion. DESIGN: Cross-sectional epidemiologic study of 417 Chinese men with a wide variation of electrolyte intakes. METHODS: Three consecutive 24-h dietary recall data and three 24-h urinary samples were obtained on the same days. Urinary analyses included calcium, sodium, potassium, magnesium and creatinine. A fasting blood sample was obtained on the first morning, and serum analyses included electrolytes, creatinine and urea nitrogen. Correlation and regression analyses were used to examine the relation between electrolyte intake and calcium excretion. RESULTS: Whilst urinary calcium was not related to dietary calcium, it was significantly correlated with dietary sodium and potassium. A linear relationship was seen between dietary sodium, potassium and urinary calcium. After adjustment for age, body mass index, serum creatinine, dietary calcium intake and other electrolytes, urinary calcium was positively related to dietary sodium and negatively related to dietary potassium. This relation was seen at different levels of dietary calcium intake. The relation between magnesium intake and calcium excretion was inconsistent. CONCLUSION: These results suggest that sodium and potassium intake influence urinary calcium excretion in normotensive men.

Identification of Zucchini yellow mosaic potyvirus by RT-PCR and analysis of sequence variability.

A reverse transcription-polymerase chain reaction (RT-PCR) method was used to identify Zucchini yellow mosaic virus (ZYMV) in leaves of infected cucurbits. Oligonucleotide primers which annealed to regions in the nuclear inclusion body (NIb) and the coat protein (CP) genes, generated a 300-bp product from ZYMV and also from the closely related watermelon mosaic virus type 2 (WMV-2). However, no product was obtained from papaya ringspot potyvirus which also infects cucurbits. ZYMV and WMV-2 were differentiated using a third primer which was complementary to a sequence in the 3'-untranslated region; a 1186-bp amplified product was obtained for ZYMV only. Nucleotide sequence analysis of the 300-bp fragments of Australian ZYMV and WMV-2 strains revealed 93.7-100% sequence identity between ZYMV strains. Multiple sequence alignments indicated that the nucleotide sequence which codes for the N-terminus of the CP was 74-100% identical for different isolates of ZYMV. The Australian isolate of WMV-2 was 43-46% identical to all isolates of ZYMV and was 84.6% identical to a Florida isolate of WMV-2.

Antibody-based spot test for NADH-cytochrome b5 reductase activity for the laboratory diagnosis of congenital methemoglobinemia.

NADH (reduced Coenzyme I)-cytochrome b5 reductase (b5R) is a multifunctional redox enzyme, whose deficiency causes recessive congenital methemoglobinemia. A novel procedure for the detection of b5R activity in human hemolysates was developed, in which b5R monoclonal antibodies dot-blotted on nitrocellulose membrane was used to capture and enrich b5R from hemolysates, and the captured b5R activity was subsequently visualized with the substrate 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide. Application of this simple method to the detection of b5R activity in the hemolysates from different subjects demonstrated that it was both sensitive and reliable. Our method would be useful for the laboratory diagnosis of congenital methemoglobinemia.

Reduction of tumorigenicity of SMMC-7721 hepatoma cells by vascular endothelial growth factor antisense gene therapy.

AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cassette in the reverse orientation transcribing small antisense RNA which could specifically interact with VEGF165, and VEGF121 mRNA. Construct the retroviral vector containing this antisense VEGF U6 cassette and package the replication-deficient recombinant retrovirus. SMMC-7721 cells were transduced with these virus and positive clones were selected with G418. PCR and Southern blot analysis were performed to determine if U6 cassette integrated into the genomic DNA of positive clone. Transfected tumor cells were evaluated for RNA expression by ribonuclease protection assays. The VEGF protein in the supernatant of parental tumor cells and genetically modified tumor cells was determined with ELISA. In vitro and in vivo growth properties of antisense VEGF cell clone in nude mice were analyzed. RESULTS: Restriction enzyme digestion and PCR sequencing verified that the antisense VEGF RNA retroviral vector was successfully constructed.After G418 selection, resistant SMMC-7721 cell clone was picked up. PCR and Southern blot analysis suggested that U6 cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transduced with U6 antisense RNA cassette could express 200 bp small antisense VEGF RNA and secrete reduced levels of VEGF in culture condition. Production of VEGF by antisense transgene-expressing cells was 65+/-10 ng/L per 10(6) cells, 42045 ng/L per 10(6) cells in sense group and 485+/-30 ng/L per 10(6) cells in the negative control group, (P< 0.05). The antisense-VEGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S.C. was implanted into nude mice, growth of antisense-VEGF cell lines was greatly inhibited compared with control cells. CONCLUSION: Expression of antisense VEGF RNA in SMMC-7721 cells could decrease the tumorigenicity, and antisense-VEGF gene therapy may be an adjuvant treatment for hepatoma.