High-frequency neural activity dysregulation is associated with sleep and psychiatric disorders in BMAL1-deficient animal models

Sleep disturbance led by BMAL1-deficiency has been recognized both in rodent and non-human primate models. Yet it remained unclear how their diurnal brain oscillations were affected upon BMAL1 ablation and what caused the discrepancy in the quantity of sleep between the two species. Here, we investigated diurnal electroencephalographs of BMAL1-deficient mice and cynomolgus monkeys at young adult age and uncovered a shared defect of dysregulated high-frequency oscillations by Kullback-Leibler divergence analysis. We found beta and gamma oscillations were significantly disturbed in a day versus night manner in BMAL1-deficient monkeys, while in mice the beta band difference was less evident. Notably, the dysregulation of beta oscillations was particularly associated with psychiatric behaviors in BMAL1-deficient monkeys, including the occurrence of self-injuring and delusion-like actions. As such psychiatric phenotypes were challenging to uncover in rodent models, our results offered a unique method to study the correlation between circadian clock dysregulation and psychiatric disorders.

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.

Phosphorylation of CENP-R by Aurora B regulates kinetochore-microtubule attachment for accurate chromosome segregation

Error-free mitosis depends on accurate chromosome attachment to spindle microtubules via a fine structure called the centromere that is epigenetically specified by the enrichment of CENP-A nucleosomes. Centromere maintenance during mitosis requires CENP-A-mediated deposition of constitutive centromere-associated network that establishes the inner kinetochore and connects centromeric chromatin to spindle microtubules during mitosis. Although previously proposed to be an adaptor of retinoic acid receptor, here, we show that CENP-R synergizes with CENP-OPQU to regulate kinetochore-microtubule attachment stability and ensure accurate chromosome segregation in mitosis. We found that a phospho-mimicking mutation of CENP-R weakened its localization to the kinetochore, suggesting that phosphorylation may regulate its localization. Perturbation of CENP-R phosphorylation is shown to prevent proper kinetochore-microtubule attachment at metaphase. Mechanistically, CENP-R phosphorylation disrupts its binding with CENP-U. Thus, we speculate that Aurora B-mediated CENP-R phosphorylation promotes the correction of improper kinetochore-microtubule attachment in mitosis. As CENP-R is absent from yeast, we reasoned that metazoan evolved an elaborate chromosome stability control machinery to ensure faithful chromosome segregation in mitosis.

[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.

SIRT7 Facilitates CENP-A Nucleosome Assembly and Suppresses Intestinal Tumorigenesis

SIRT7 is a member of the mammalian sirtuins and functions as an NAD+-dependent deacylase. Here we show that SIRT7 deficiency leads to a lowered histone acetyltransferase 1 (HAT1) activity and therefore decreased histone H4K5 and H4K12 acetylation. This in turn causes CENP-A dislocation at the centromere, which further affects chromatin assembly. SIRT7 ablation results in aneuploidy and aging phenotypes, including senescence and nucleolar expansion. Moreover, SIRT7 knockout mice are susceptible to DSS-induced colitis and alcohol-derived epithelial disturbance, revealing a disrupted intestinal epithelial homeostasis. Notably, absence of SIRT7 aggravates the susceptibility of colorectal cancer incidence in APCMin/+ mouse model and elicits further the Wnt signaling. Our findings indicate a tumor suppressive role of SIRT7 in the case of colorectal cancer. Together with the activities in maintaining genome integrity and intestinal homeostasis, activating SIRT7 may serve as a strategy to treat bowel diseases and colorectal cancer.

Endothelial CDS2 deficiency causes VEGFA-mediated vascular regression and tumor inhibition

The response of endothelial cells to signaling stimulation is critical for vascular morphogenesis, homeostasis and function. Vascular endothelial growth factor-a (VEGFA) has been commonly recognized as a pro-angiogenic factor in vertebrate developmental, physiological and pathological conditions for decades. Here we report a novel finding that genetic ablation of CDP-diacylglycerol synthetase-2 (CDS2), a metabolic enzyme that controls phosphoinositide recycling, switches the output of VEGFA signaling from promoting angiogenesis to unexpectedly inducing vessel regression. Live imaging analysis uncovered the presence of reverse migration of the angiogenic endothelium in cds2 mutant zebrafish upon VEGFA stimulation, and endothelium regression also occurred in postnatal retina and implanted tumor models in mice. In tumor models, CDS2 deficiency enhanced the level of tumor-secreted VEGFA, which in-turn trapped tumors into a VEGFA-induced vessel regression situation, leading to suppression of tumor growth. Mechanistically, VEGFA stimulation reduced phosphatidylinositol (4,5)-bisphosphate (PIP2) availability in the absence of CDS2-controlled-phosphoinositide metabolism, subsequently causing phosphatidylinositol (3,4,5)-triphosphate (PIP3) deficiency and FOXO1 activation to trigger regression of CDS2-null endothelium. Thus, our data indicate that the effect of VEGFA on vasculature is context-dependent and can be converted from angiogenesis to vascular regression.

CDK9 modulates circadian clock by attenuating REV-ERBα activity

Circadian clock and cell cycle are vital cellular programs acting in a timely-regulated, cyclic manner. The two cellular oscillators are coupled in various ways to facilitate biological processes. Here we report CDK9, a kinase belongs to the CDK family in regulating cell cycle and RNA Pol II activity, can serve as a modulator for circadian clock. We identified CDK inhibitor LY2857785 potently blocked PER2:LUC expression in MEFs from a screen of 17 commonly-used CDK inhibitors. We further analyzed the possible targets of LY2857785 by siRNA approach, and confirmed CDK9 as the main effector. LY2857785 treatment, as well as Cdk9 knock-down, led to lowered expression of Bmal1 in accordance with elevated expression of Rev-Erbα. CDK9 associated with REV-ERBα thus attenuated REV-ERBα binding to the RORE for Bmal1 suppression. To conform the circadian-modulating activity of CDK9 in vivo, we knocked down CDK9 in mice at the anterior hypothalamus covering the central oscillator SCN, and found the respiratory exchange ratio, daily activity and circadian period were altered in the Cdk9-knockdown mice. Together, our finding designated CDK9 as a novel modulator in circadian clock. CDK9 may serve as a vital basis to understand circadian- and cell cycle-misregulated ailments such as cancer.

BMAL1 knockout macaque monkeys display reduced sleep and psychiatric disorders

Circadian disruption is a risk factor for metabolic, psychiatric and age-related disorders, and non-human primate models could help to develop therapeutic treatments. Here, we report the generation of BMAL1 knockout cynomolgus monkeys for circadian-related disorders by CRISPR/Cas9 editing of monkey embryos. These monkeys showed higher nocturnal locomotion and reduced sleep, which was further exacerbated by a constant light regimen. Physiological circadian disruption was reflected by the markedly dampened and arrhythmic blood hormonal levels. Furthermore, BMAL1-deficient monkeys exhibited anxiety and depression, consistent with their stably elevated blood cortisol, and defective sensory processing in auditory oddball tests found in schizophrenia patients. Ablation of BMAL1 up-regulated transcriptional programs toward inflammatory and stress responses, with transcription networks associated with human sleep deprivation, major depressive disorders, and aging. Thus, BMAL1 knockout monkeys are potentially useful for studying the physiological consequences of circadian disturbance, and for developing therapies for circadian and psychiatric disorders.

Pre-treatment Dietary Patterns Are Associated with the Presence of Symptoms 1 Year after Diagnosis in Patients with Head and Neck Cancer

Ninety percent of head and neck cancer (HNC) survivors experience disease and treatment related symptoms. Diet has the potential to reduce inflammation, modulate epigenetic changes and affect biological processes involved in the pathogenesis of symptoms. The objective of this study was to determine if pre-treatment dietary patterns are associated with the presence of symptoms 1-year after diagnosis. Methods: This was a longitudinal study of 295 newly diagnosed HNC patients. All patients completed a food frequency questionnaire and epidemiologic health survey. Self-reported symptoms were assessed pre-treatment and 1-year after diagnosis using a Likert scale ranging from “1: not at all bothered” by symptom to “5: extremely bothered”. Symptom scores were dichotomized as “not at all” vs. “slight - extremely”. Principal component analysis was used to derive pre-treatment dietary patterns. Multivariable logistic regression models examined the association of derived dietary patterns (fit by quartiles) and seven symptoms (trismus, xerostomia, dysphagia of liquids, dysphagia of solids, difficulty chewing, taste and mucositis). An overall symptom summary score was calculated (range 8–39) and dichotomized as <17 vs. ≥17. This cut-off was chosen by examining the distribution of scores and categorizing into two distinct subgroups naturally present in the data. Results: Two dietary patterns emerged: Prudent (high intakes of vegetables, fruit, fish, poultry, and whole grains) and Western (high intakes of red and processed meats, refined grains, potatoes, and French fries). After adjusting for age, baseline symptoms, tumor site, cancer stage, smoking, calories and HPV status, significant inverse associations were observed between pre-treatment Prudent pattern score and dysphagia of liquids (P = 0.01), dysphagia of solids (P = 0.02) and difficulty chewing (P = 0.02) at 1 year post- diagnosis. A statistically significant inverse association was observed between the overall symptom summary score and the Prudent pattern (P < 0.001). No significant associations were observed between the Western pattern and symptoms. Conclusion: Consumption of a pre-treatment Prudent diet may help reduce the risk of symptoms such as dysphagia and difficulty chewing 1-year after diagnosis in HNC survivors.

Aneuploid Cell Survival Relies upon Sphingolipid Homeostasis

Aneuploidy, a hallmark of cancer cells, poses an appealing opportunity for cancer treatment and prevention strategies. Using a cell-based screen to identify small molecules that could selectively kill aneuploid cells, we identified the compound N-[2-hydroxy-1-(4-morpholinylmethyl)-2-phenylethyl]-decanamide monohydrochloride (DL-PDMP), an antagonist of UDP-glucose ceramide glucosyltransferase. DL-PDMP selectively inhibited proliferation of aneuploid primary mouse embryonic fibroblasts and aneuploid colorectal cancer cells. Its selective cytotoxic effects were based on further accentuating the elevated levels of ceramide, which characterize aneuploid cells, leading to increased apoptosis. We observed that DL-PDMP could also enhance the cytotoxic effects of paclitaxel, a standard-of-care chemotherapeutic agent that causes aneuploidy, in human colon cancer and mouse lymphoma cells. Our results offer pharmacologic evidence that the aneuploid state in cancer cells can be targeted selectively for therapeutic purposes, or for reducing the toxicity of taxane-based drug regimens. Cancer Res; 77(19); 5272-86. ©2017 AACR.

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.

Gene copy-number alterations: a cost-benefit analysis

Changes in DNA copy number, whether confined to specific genes or affecting whole chromosomes, have been identified as causes of diseases and developmental abnormalities and as sources of adaptive potential. Here, we discuss the costs and benefits of DNA copy-number alterations. Changes in DNA copy number are largely detrimental. Amplifications or deletions of specific genes can elicit discrete defects. Large-scale changes in DNA copy number can also cause detrimental phenotypes that are due to the cumulative effects of copy-number alterations of many genes simultaneously. On the other hand, studies in microorganisms show that DNA copy-number alterations can be beneficial, increasing survival under selective pressure. As DNA copy-number alterations underlie many human diseases, we will end with a discussion of gene copy-number changes as therapeutic targets.

Identification of aneuploidy-selective antiproliferation compounds

Aneuploidy, an incorrect chromosome number, is a hallmark of cancer. Compounds that cause lethality in aneuploid, but not euploid, cells could therefore provide new cancer therapies. We have identified the energy stress-inducing agent AICAR, the protein folding inhibitor 17-AAG, and the autophagy inhibitor chloroquine as exhibiting this property. AICAR induces p53-mediated apoptosis in primary mouse embryonic fibroblasts (MEFs) trisomic for chromosome 1, 13, 16, or 19. AICAR and 17-AAG, especially when combined, also show efficacy against aneuploid human cancer cell lines. Our results suggest that compounds that interfere with pathways that are essential for the survival of aneuploid cells could serve as a new treatment strategy against a broad spectrum of human tumors.

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.

Structural features of the GroEL-GroES nano-cage required for rapid folding of encapsulated protein

GroEL and GroES form a chaperonin nano-cage for proteins up to approximately 60 kDa to fold in isolation. Here we explored the structural features of the chaperonin cage critical for rapid folding of encapsulated substrates. Modulating the volume of the GroEL central cavity affected folding speed in accordance with confinement theory. Small proteins (approximately 30 kDa) folded more rapidly as the size of the cage was gradually reduced to a point where restriction in space slowed folding dramatically. For larger proteins (approximately 40-50 kDa), either expanding or reducing cage volume decelerated folding. Additionally, interactions with the C-terminal, mildly hydrophobic Gly-Gly-Met repeat sequences of GroEL protruding into the cavity, and repulsion effects from the negatively charged cavity wall were required for rapid folding of some proteins. We suggest that by combining these features, the chaperonin cage provides a physical environment optimized to catalyze the structural annealing of proteins with kinetically complex folding pathways.

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.

Selenite-induced survival of HuH7 hepatoma cells involves activation of focal adhesion kinase-phosphatidylinositol 3-kinase-Akt pathway and Rac1

Selenium has been shown to sustain the growth of selected human hepatocellular carcinoma cell lines under serum-free conditions, but the detailed mechanism remained undetermined. In the present study, the molecular mechanism(s) involving sodium selenite (Na2SO3, Se) as a survival agent were determined. Selenite not only protects HuH7 cells from serum deprivation-induced apoptosis, it also supports its long-term growth in sodium selenite (10(-7)m) supplemented serum-free medium. The anti-apoptotic effect correlates with activation of focal adhesion kinase and the phosphatidylinositol 3-kinase (PI3K)-Akt kinase pathway. Using HuH7 cells stably transfected with a constitutively active Akt kinase and PI3K inhibitor LY294002, selenite-induced cell survival was shown to be PI3K-Akt-dependent. Parallel changes included a significant reduction in the intracellular reactive oxygen species content, the reversal of DNA fragmentation, and the suppression of caspase and apoptosis signal-regulating kinase 1 activities. HuH7 cells stably expressing a Rac1 mutant N17 (Rac1N17-HuH7) are refractory to selenite treatment. In these cells selenite supplement neither triggers Akt activation nor supports cell proliferation. Participation of Rac1 activation in this event is supported by the fact that selenite treatment drastically enhanced activation of Rac1. The exact link between selenite treatment, Rac1 activation, and activation of the focal adhesion kinase-PI 3-kinase, however, remains to be characterized. The mitogenic signaling mediated by selenite may involve unconventional growth stimuli including higher glutathione peroxidase 1 activity and higher transcription levels of selenoprotein P. The selenium-HuH7 system we have established thus provides a unique tool that will allow the biological role of selenite in growth regulation of hepatocytes to be studied in detail.

The anti-tumour effect of Klebsiella pneumoniae capsular polysaccharides

K24 capsular polysaccharide (K24-CPS), with a known structure of a repeating unit, was isolated from the capsule of Klebsiella pneumoniae serotype K24. The polysaccharide was found to suppress the proliferation of Ehrlich ascites tumour (EAT) cells in vitro, but did not alter the cell cycle distribution of cells. K24-CPS treatment reduced the tyrosine phosphorylation of some proteins in EAT cells. Furthermore, the treatment also decreased the expression of c-JUN, but had no effect on the levels of c-FOS and c-MYC. It is speculated that the growth suppression effect of K24-CPS may be related to its effect in down-regulating c-JUN expression.

Emergency laparoscopic orchidectomy for torsion of intra-abdominal testis: a case report

Torsion of an intraabdominal testis is a rare cause of acute abdominal pain. With a history of undescended testis, it is difficult to establish the diagnosis and to exclude other emergency abdominal conditions without a laparotomy. The following case report illustrates the usefulness of laparoscopy as a diagnostic as well as a therapeutic tool in such a condition.

Reduction of tumorigenicity of SMMC-27721 hepatoma cells by vascular endothelial growth factor antisense gene therapy

AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatomacells may inhibit tumor growth using the rat hepatoma model.

METHODS: Amplifiy 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 transgenea2expressing cells was 65 ± 10 ng/L per 10⁶ cells, 420 ± 45 ng/L per 10⁶ cells in sense group and 485 ± 30 ng/ L per 10⁶ cells in the negative control group, (P < 0.5). 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.

A novel mutation in the NADH-cytochrome b5 reductase gene of a Chinese patient with recessive congenital methemoglobinemia

Recessive congenital methemoglobinemia due to nicotinamide adenine dinucleotide (NADH)-cytochrome b5 reductase (b5R) deficiency is classified into 2 clinical types: type 1 (erythrocyte type) and type 2 (generalized type). We found a Chinese family with type 1 recessive congenital methemoglobinemia, the patients from which were diagnosed according to clinical symptoms and b5R enzyme activity in the blood cells. To learn the molecular basis of type 1 recessive congenital methemoglobinemia in this Chinese family, we isolated total RNA from the peripheral leukocytes of the propositus and b5R complementary DNA (cDNA) by reverse transcription- polymerase chain reaction (RT-PCR). The coding region of the b5R cDNA was analyzed by sequencing the cloned PCR products. The results showed that the propositus was homozygous for a G-->A transition at codon 203 in exon 7, changing a cysteine to a tyrosine (Cys203Tyr). To characterize the mutant enzyme, both glutathione S-transferase (GST)-fused wild-type b5R and GST-fused mutant Cys203Tyr b5R were expressed in Escherichia coli and affinity purified. The results showed that the catalytic activity of the enzyme was not much affected by this amino acid substitution, but the mutant enzyme exhibited decreased heat stability and increased susceptibility to trypsin. These properties of the mutant enzyme would account for the restricted b5R deficiency and mild clinical manifestations of these type 1 patients. The finding of this novel mutation makes codon 203 the only position within the b5R gene at which more than 1 mutation has been found.

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.

Testicular catch-up growth after varicocele correction in adolescents

We evaluated retrospectively the outcome of artery-sparing (AS) versus non-artery-sparing (NAS) laparoscopic varicocelectomy and measured any reversal of testicular growth. Twenty patients (13 left and 7 bilateral varicoceles) were evaluated after surgery. A total of 27 varicocelectomies (20 AS and 7 NAS) were performed. The indication for surgery was smaller testicular size on the affected side in all patients and discomfort/pain in 3. The mean age was 12.9 years (range 8-15 years) at surgery. The testicular volumes were determined clinically and by color Doppler sonography (US). The follow-up time was 6-48 months after surgery. There were 4 recurrences out of 27 varicocelectomies (15%), of which 1 has been reoperated. Testicular volumes were equal in both groups after surgery, indicating catch-up growth except in the cases with minor recurrences (2 AS and 2 NAS varicocelectomies). In 12 testes, dilated veins in the pampiniform plexus were revealed by US. No severe intraoperative complications occurred. Three patients had a hydrocele after surgery (11%). These data show that there is testicular catch-up growth after varicocelectomy, but some questions remain unanswered: (1) should the remaining dilated veins detected by Doppler US be tackled; and (2) is an AS operation worthwhile?

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.

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.

Changes in phrenic, hypoglossal and recurrent laryngeal nerve activities after intravenous infusions of aminophylline in cats

Aminophylline is known to have respiratory stimulant properties, and it has been suggested that it may also be effective in sleep apnoea. However, its role in this disorder remains uncertain. Theoretically, increasing upper airway motoneural activity in order to maintain airway patency might alleviate obstructive sleep apnoea. On the other hand, increasing the respiratory drive may also prove beneficial in treating central sleep apnoea. In these studies, we attempted to determine the effect of aminophylline on neural activities of the upper airway and diaphragm. We administered intravenously either a low dose (4 mg.kg-1) or a high dose (16 mg.kg-1) of aminophylline to decerebrated, vagotomized and paralysed cats, and continuously recorded the phrenic hypoglossal and recurrent laryngeal nerve activities for 3 h. Results showed that a high dose of aminophylline induced a marked increase in phrenic nerve activity, but not hypoglossal or recurrent laryngeal nerve activity. In a group treated with a low dosage of aminophylline, a significant increase of activity was found in all three nerves. Furthermore, phrenic nerve activity increased more with a high dose than with a low dose. We confirmed that aminophylline has dose-dependent and selective effects on respiratory neural activity. A low dose acts on the upper airway and diaphragm, but a high dose induces a marked increase in central respiratory drive. According to our results, low dose aminophylline might be beneficial in obstructive sleep apnoea, whereas, a high or low dose might improve some cases of central sleep apnoea.

Changes in phrenic, hypoglossal and recurrent laryngeal nerve activities after intravenous infusions of aminophylline in cats

Aminophylline is known to have respiratory stimulant properties, and it has been suggested that it may also be effective in sleep apnoea. However, its role in this disorder remains uncertain. Theoretically, increasing upper airway motoneural activity in order to maintain airway patency might alleviate obstructive sleep apnoea. On the other hand, increasing the respiratory drive may also prove beneficial in treating central sleep apnoea. In these studies, we attempted to determine the effect of aminophylline on neural activities of the upper airway and diaphragm. We administered intravenously either a low dose (4 mg.kg-1) or a high dose (16 mg.kg-1) of aminophylline to decerebrated, vagotomized and paralysed cats, and continuously recorded the phrenic hypoglossal and recurrent laryngeal nerve activities for 3 h. Results showed that a high dose of aminophylline induced a marked increase in phrenic nerve activity, but not hypoglossal or recurrent laryngeal nerve activity. In a group treated with a low dosage of aminophylline, a significant increase of activity was found in all three nerves. Furthermore, phrenic nerve activity increased more with a high dose than with a low dose. We confirmed that aminophylline has dose-dependent and selective effects on respiratory neural activity. A low dose acts on the upper airway and diaphragm, but a high dose induces a marked increase in central respiratory drive. According to our results, low dose aminophylline might be beneficial in obstructive sleep apnoea, whereas, a high or low dose might improve some cases of central sleep apnoea.

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.

[Rapid diagnosis of pulmonary Pseudomonas aeruginosa infections by indirect immunofluorescent antibody]

167 sputum specimens collected from patients with pulmonary infection were tested by IFA (Indirect immunofluorescent antibody-staining) with serogroup-specific monoclonal antibody to Pseudomonas aeruginosa, compared with quantitative sputum culture. The results showed the minimum concentration of bacteria detectable by IFA was 10 cfu/ml. 31(86.1%) were positive in 36 specimens with more than 10 cfu/ml of Pseudomonas aeruginosa. 22(100%) were positive in 22 specimens with more than 10 cfu/ml of Pseudomonas aeruginosa. In 127 specimens with a negative culture for Pseudomonas aeruginosa, 121(95.2%) were negative, 6(4.8%) were false-positive which could be identified by Gram's-staining. The type of Pseudomonas aeruginosa could also be identified within 3 hours.

Relation of serum zinc and copper to lipids and lipoproteins: the Yi People Study

The relations of serum zinc (Zn) and copper (Cu) to serum total cholesterol (TC), low-density-lipoprotein and high-density-lipoprotein cholesterol (LDL-C and HDL-C) and triglycerides were investigated in a population-based sample of 399 men in Southern China. Serum Cu was inversely related to HDL-C (r = -0.21), while Zn/Cu ratio showed a positive association (r = 0.19). These relationships remained significant after adjusting for age, body mass index (kg/m2), physical activity, tobacco smoking and dietary cholesterol, fat, and fiber. While no significant association was observed between serum Cu and serum TC in univariate analysis, a significant negative association was observed in multivariate analysis, after adjustment for the above mentioned independent variables. No significant association between serum Cu and LDL-C was found. These observations, as well as those reported in other studies reviewed herein, suggest that Cu is implicated in the metabolism of HDL-C, although the mechanism involved is not fully understood. No significant associations were found between serum Zn and the lipid variables.

Effect of migration on blood pressure: the Yi People Study

The Yi People Study was conducted in Puge County, Sichuan Province, People's Republic of China. Four population groups were surveyed for risk factors for cardiovascular disease. Included were two groups of Yi farmers living either in a high mountainous area in extremely remote villages at or above 2,750 meters elevation, or in a mountainside area at about 1,800 meters elevation. A third study group consisted of Yi farmers who migrated to the county seat during the 1950s. Local residents of the county seat, the Han people, constituted the fourth group. Blood pressure rises very little with age after puberty in Yi farmers, but there was a trend of increasing blood pressure with age in Yi migrants and Han. Mean body mass index (kg/m2) and heart rate were higher in Yi migrants than in Yi farmers. For men, both systolic and diastolic blood pressure were greater among Yi migrants than among Yi farmers. These differences persisted after adjusting for age and body mass index. Among women, after adjusting for age, BMI, and altitude, only diastolic blood pressure was lower among Yi farmers than Yi migrants. Yi migrants and Han had similar blood pressures. In 1986, a sample of men participated in more detailed studies of diet, serum, and urine. The proportion of energy from fat ranged from less than 10% among high-mountain Yi farmers to almost 40% among Yi migrants and Han. Compared with Yi farmers, Yi migrants consumed more sodium and less potassium, calcium, and magnesium, had lower serum potassium, and a greater sodium/potassium ratio. Urinary excretion of sodium, calcium, and the sodium/potassium ratio were all greater in Yi migrants than in Yi farmers, while the reverse was seen for potassium. These data suggest that changes in life-style, including dietary changes, contribute importantly to the higher blood pressure among Yi migrants.

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)

The prevalence of chromosome diseases in the general population of Sichuan, China

Chromosome abnormalities with recognizable clinical manifestations including mental retardation, primary infertility or primary amenorrhea of unknown etiology, abnormal sex differentiation and abnormal sex development were surveyed in the general population of Sichuan. The results showed that the prevalence of chromosome diseases in Sichuan was 31.5 per 100,000 of the general population with almost equal frequencies for autosomal chromosome and sex chromosome diseases. The most frequent autosomal chromosome disease was Down syndrome. The prevalence was 14.2 per 100,000 for the total population, and there should therefore be 154,000 cases of Down syndrome in the whole of China with its population of 1,100 million people. The most frequent sex chromosome diseases were Turner syndrome and Klinefelter syndrome. The prevalences were 14.3 and 14.1 per 100,000 for females and males, respectively. The majority of autosomal chromosome diseases clustered in the younger age groups, while the highest detection rate of sex chromosome diseases was found in the age group of 25-35, and thereafter it decreased with age. The age distribution of the cases indicates that both autosomal and sex chromosome diseases reduce the lifespan of patients.

5p;12q translocation with manifestations of cri du chat syndrome and Marfanoid arachnodactyly

A 12-year-old boy with a history of a mewing cry after birth, severe mental retardation, Marfanoid arachnodactyly, general osteomalacia and multiple bone fractures was found to have a de novo 5p;12q chromosomal translocation. The karyotype is 46,XY,t(5;12)(12qter----12q24.1::5p15----cen----5qt er; 12pter----cen----12q24.1). The karyotypes of other examined family members are normal. The manifestations of cri du chat syndrome are explained by the loss of a small segment of 5p15 which is responsible for the major stigmata of the syndrome, and the abnormalities of the osseous system may be the results of untreated vitamin D resistant rickets.

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.