[Preliminary study on implementation of modified tubular gastric side-overlap anastomosis in laparoscopic proximal gastrectomy]

Objective: To investigate the feasibility and safety of implementing modified tubular gastric side-overlap anastomosis in laparoscopic proximal gastrectomy. Methods: In this retrospective, descriptive case series, we analyzed clinical data of seven patients who had undergone laparoscopic proximal gastrectomy and gastrointestinal reconstruction with modified tubular gastric side-overlap anastomosis from October 2022 to March 2023 in the Second Affiliated Hospital of Fujian Medical University. The study patients comprised five men and two women aged 57-72 years and of body mass index 18.5-25.7 kg/m2. All seven patients had preoperative gastroscopic and pathological evidence of esophagogastric junction cancer and all were found by preoperative enhanced computed tomography and/or endoscopic ultrasonography to have stage CT1-2N0M0 tumors. The main steps in the reconstruction of a modified tubular gastric side-overlap anastomosis are as follows: (1) mobilizing the lower esophagus and opening the left pleura to expand the space; (2) severing the esophagus with a linear cutter stapler; (3) creating a 3-cm-wide tubular stomach along the greater curvature; (4) creating a 5-cm guide line on the lesser curvature of the anterior wall of the tubular stomach and a small opening below the guide line; (5) rotating the esophageal stump 90° counterclockwise and making a small opening on the right posterior wall of the esophageal stump, along with using a 45-mm linear cutter stapler for esophagogastric side-to-side anastomosis under the guidance of the gastric tube and guide line ; (6) closing the common opening using barbed sutures; (7) embedding the cut edge of the esophageal stump such as to closely oppose it to the esophagus; (8) using barbed sutures to continuously suture the lower esophagus bilaterally to the anterior wall of the tubular stomach; and (9) closing the opened esophageal hiatus and pleura. The main outcome measures were intraoperative (operation time, digestive tract reconstruction time, closing the common opening time, intraoperative blood loss, and number of dissected lymph nodes), postoperative (time to passage of flatus , time to liquid diet, time to ambulation, length of postoperative hospital stay, and postoperative complications), pathological (maximum diameter of the tumor and pathological stage) and findings on follow-up. Results: Laparoscopic proximal gastrectomy with reconstruction of a modified tubular gastric side-overlap anastomosis was successfully completed in all seven patients; no conversion to laparotomy was required and there were no postoperative complications. The operation time, digestive tract reconstruction time, and closing of common opening time were 187-229, 61-79, and 7-9 minutes, respectively. Intraoperative blood loss was 15-23 ml and the number of dissected lymph nodes was 14-46 per case. Time to passage of flatus, time to liquid diet, time to ambulation, and postoperative hospital stay were 1-2, 2-3, 3-4, and 6-7 days, respectively. Postoperative pathological examination showed that the maximum tumor diameters were 1.6-3.3 cm in four patients with stage IA disease and three patients with stage IB. The seven patients were followed up for 6-11 months, during which none required routine use of proton pump inhibitors or gastric mucosal protective agents and there were no deaths or tumor recurrence/metastasis. No patients had anemia or hypoproteinemia 3 and 6 months after surgery. Six months after surgery, NRS2002 and GERDQ scores were 1-2 and 2-3, respectively. Gastroscopy showed narrow anastomoses in 6 patients with Los Angeles grade A and one patient with grade B disease. No evidence of significant bile reflux was found and no anastomotic stenosis or reflux was detected on upper gastrointestinal angiography. Conclusion: It is safe and feasible to implement modified tubular gastric side-overlap anastomosis for digestive tract reconstruction in laparoscopic proximal gastrectomy.

Syphilis epidemic among men who have sex with men: A global systematic review and meta-analysis of prevalence, incidence, and associated factors

Background

We aimed to estimate the prevalence and incidence of syphilis at global, regional and national levels for human immunodeficiency virus (HIV)-positive and HIV-negative men who have sex with men (MSM) and explore the association between demographic and social behavioural factors and syphilis infection.

Methods

We searched PubMed, Embase, and the Cochrane Library from 1 January 2012 to 31 December 2022 for studies of reported crude syphilis prevalence or incidence in MSM or with sufficient data to calculate prevalence or incidence rate in MSM.

Results

We included 376 articles reporting on 409 records from 62 countries to calculate syphilis prevalence and incidence in MSM. The pooled prevalence of syphilis in MSM was 10.4%, with substantial differences between countries and regions. Syphilis prevalence was substantially higher in HIV-positive than in HIV-negative MSM. The pooled incidence of syphilis in MSM was 76.4 per 1000 person-years. Older age, lower education, nitrite or recreational drug use, group sex, and multiple sexual partners were identified as risk factors for syphilis infection.

Conclusions

A disproportionate geographic pattern of syphilis infection in MSM and significant threats of syphilis infection were revealed. The 'hidden risk' in specific regions and the inadequately elucidated drivers of high-risk behaviours, need to be fully acknowledged and addressed.

Registration

PROSPERO: CRD42023422218.

Heart failure-related genes associated with oxidative stress and the immune landscape in lung cancer

Background

Lung cancer is a common comorbidity of heart failure (HF). The early identification of the risk factors for lung cancer in patients with HF is crucial to early diagnosis and prognosis. Furthermore, oxidative stress and immune responses are the two critical biological processes shared by HF and lung cancer. Therefore, our study aimed to select the core genes in HF and then investigate the potential mechanisms underlying HF and lung cancer, including oxidative stress and immune responses through the selected genes.

Methods

Differentially expressed genes (DEGs) were analyzed for HF using datasets extracted from the Gene Expression Omnibus database. Functional enrichment analysis was subsequently performed. Next, weighted gene co-expression network analysis was performed to select the core gene modules. Support vector machine models, the random forest method, and the least absolute shrinkage and selection operator (LASSO) algorithm were applied to construct a multigene signature. The diagnostic values of the signature genes were measured using receiver operating characteristic curves. Functional analysis of the signature genes and immune landscape was performed using single-sample gene set enrichment analysis. Finally, the oxidative stress-related genes in these signature genes were identified and validated in vitro in lung cancer cell lines.

Results

The DEGs in the GSE57338 dataset were screened, and this dataset was then clustered into six modules using weighted gene co-expression network analysis; MEblue was significantly associated with HF (cor = -0.72, p < 0.001). Signature genes including extracellular matrix protein 2 (ECM2), methyltransferase-like 7B (METTL7B), meiosis-specific nuclear structural 1 (MNS1), and secreted frizzled-related protein 4 (SFRP4) were selected using support vector machine models, the LASSO algorithm, and the random forest method. The respective areas under the curve of the receiver operating characteristic curves of ECM2, METTL7B, MNS1, and SFRP4 were 0.939, 0.854, 0.941, and 0.926, respectively. Single-sample gene set enrichment analysis revealed significant differences in the immune landscape of the patients with HF and healthy subjects. Functional analysis also suggested that these signature genes may be involved in oxidative stress. In particular, METTL7B was highly expressed in lung cancer cell lines. Meanwhile, the correlation between METTL7B and oxidative stress was further verified using flow cytometry.

Conclusion

We identified that ECM2, METTL7B, MNS1, and SFRP4 exhibit remarkable diagnostic performance in patients with HF. Of note, METTL7B may be involved in the co-occurrence of HF and lung cancer by affecting the oxidative stress immune responses.

The association between GLIM criteria defined malnutrition and 2-year unplanned hospital admission in outpatients with unintentional weight loss: A retrospective cohort study

BACKGROUND

This study aimed to assess malnutrition using the Global Leadership Initiative on Malnutrition (GLIM) criteria and Subjective Global Assessment (SGA) at baseline and determine the GLIM criteria that best predicted unplanned hospitalization in unintentional weight loss (UWL) outpatients.

METHODS

We performed a retrospective cohort study of 257 adult outpatients with UWL. The GLIM criteria and SGA agreement were reported using Cohen's kappa coefficient. Kaplan-Meier survival curves and adjusted Cox regression analyses were used for survival data. Logistic regression was used for the other correlation analysis.

RESULTS

This study collected data from 257 patients for 2 years. Based on the GLIM criteria and SGA, malnutrition prevalence was 79.0% and 72.0%, respectively (k = 0.728, P < 0.001). Using SGA as a standard, GLIM had a sensitivity of 97.8%, a specificity of 69.4%, a positive predictive value of 89.2%, and a negative predictive value of 92.6%. Malnutrition was associated with higher rates of unplanned hospital admission independent of other prognostic factors (GLIM: hazard ratio (HR) 2.85, 95% confidence interval (CI): 1.22 to 6.68; SGA: HR 2.07, 95% CI: 1.13 to 3.79). Of the five GLIM criteria-related diagnostic combinations, disease burden or inflammation was the most important to predict unplanned hospital admission in multivariable analysis (HR 3.27, 95% CI: 2.03 to 5.28).

CONCLUSION

There was good agreement between the GLIM criteria and SGA. GLIM-defined malnutrition, as well as all five GLIM criteria-related diagnosis combinations, had the potential to predict unplanned hospital admissions in UWL outpatients within 2 years. This article is protected by copyright. All rights reserved.

[Phenotypic and genotypic characteristics of Escherichia coli causing bloodstream and abdominal co-infection]

Objective: To analyze the phenotypic and genotypic characteristics of Escherichia coli causing bloodstream and abdominal co-infection (CoECO), and provide clues for empirical antibiotics treatment. Methods: The strains of Escherichia coli isolated from blood and abdominal samples in the Department of Laboratory Medicine of the First Medical Center of the PLA General Hospital from 2010 to 2020 were retrospectively analyzed. Mass spectrometer was used to identify all of the strains and the minimum inhibitory concentration (MIC) were detected by VITEK 2 Compact. All isolates were sequenced by 2×150 bp double terminal sequencing strategy on the HiSeq X Ten sequencer (Illumina). After the genome sequence was spliced, the single nucleotide polymorphism (SNP) analysis of the strain sequence was performed using kSNP3 software to clarify the homologous relationship between strains. If the strains isolated from two different parts had high homology, they were regarded as the same strain and the case was with CoECO infection. Meanwhile, the multilocus sequence type (MLST) was determined using PubMLST website and resistant genes were screened by CARD website. Results: A total of 70 cases of CoECO infection were screened, including 45 males and 25 females, and aged (59.2±16.3) years old. The 70 CoECO isolates belonged to 35 sequence types (STs). The most prevalent STs included ST38 (n=6), ST 405 (n=6), ST 1193 (n=6) and ST131 (n=5), and other ST types contained less than 5 strains. The homologous relationship among strains was relatively scattered, presenting a sporadic trend as a whole, and only a few strains had a small-scale outbreak. The CoECO isolates showed significantly resistance to ampicillin (91.4%, 64/70), ampicillin/sulbactam (74.3%, 5 2/70), ceftriaxone (72.9%, 51/70), ciprofloxacin (71.4%, 50/70) and levofloxacin (71.4%, 50/70), and high-sensitivity to piperacillin/tazobactam, carbapenems and amikacin. The most prevalent resistant gene was tet (A/B) (70%, 49/70), followed by bla_TEM (58.6%, 41/70), sul1 (55.7%, 40/70), sul2 (54.3%, 38/70), bla_CTX-M-14(25.7%, 18/70), bla_CTX-M-15(17.1%, 13/70), bla_CTX-M-55(15.7%, 11/70), bla_CTX-M-64/65(5.7%, 4/70), bla_CTX-M-27(4.3%, 3/70), mcr-1 (4.3%, 3/70), bla_NDM-5(2.9%, 2/70). Conclusions: CoECO is distributed dispersedly and has no obvious advantage clone. No genotype with obvious advantages was found. Although the strain has a high resistance rate to some antibacterial drugs, the proportion of carrying resistant genes is low, and it has a high sensitivity to some first-line antibacterial drugs.

Genome-wide analysis of mitochondrial DNA copy number reveals loci implicated in nucleotide metabolism, platelet activation, and megakaryocyte proliferation

Mitochondrial DNA copy number (mtDNA-CN) measured from blood specimens is a minimally invasive marker of mitochondrial function that exhibits both inter-individual and intercellular variation. To identify genes involved in regulating mitochondrial function, we performed a genome-wide association study (GWAS) in 465,809 White individuals from the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium and the UK Biobank (UKB). We identified 133 SNPs with statistically significant, independent effects associated with mtDNA-CN across 100 loci. A combination of fine-mapping, variant annotation, and co-localization analyses was used to prioritize genes within each of the 133 independent sites. Putative causal genes were enriched for known mitochondrial DNA depletion syndromes (p = 3.09 × 10-15) and the gene ontology (GO) terms for mtDNA metabolism (p = 1.43 × 10-8) and mtDNA replication (p = 1.2 × 10-7). A clustering approach leveraged pleiotropy between mtDNA-CN associated SNPs and 41 mtDNA-CN associated phenotypes to identify functional domains, revealing three distinct groups, including platelet activation, megakaryocyte proliferation, and mtDNA metabolism. Finally, using mitochondrial SNPs, we establish causal relationships between mitochondrial function and a variety of blood cell-related traits, kidney function, liver function and overall (p = 0.044) and non-cancer mortality (p = 6.56 × 10-4).

Genetically predicted circulating levels of copper and zinc are associated with osteoarthritis but not with rheumatoid arthritis

OBJECTIVE

Osteoarthritis (OA) and rheumatoid arthritis (RA) are both debilitating diseases that cause significant morbidity and disability globally. This study aims to investigate the causal effects of varying blood levels of five minerals -- iron, zinc, copper, calcium, and magnesium, on OA and RA.

DESIGN

We performed two-sample Mendelian randomization (MR) analyses to assess the associations of five circulating minerals with OA and RA. Single nucleotide polymorphisms (SNPs) serving as genetic instruments for the circulating mineral levels were selected from large genome-wide association studies of European-descent individuals. The associations of these SNPs with OA and RA were evaluated in UK Biobank participants. Multiple sensitivity analyses were applied to detect and correct for the presence of pleiotropy.

RESULTS

Genetically determined copper and zinc status were associated with OA, but not with RA. Per standard deviation (SD) increment in copper increases the risk of OA (OR = 1.07, 95% CI: 1.02-1.13) and one of its subtypes, localized OA (OR = 1.08, 95% CI: 1.03-1.15). Per SD increment in zinc is positively associated with risks of OA (OR = 1.07, 95% CI: 1.01-1.13), generalized OA (OR = 1.18, 95% CI: 1.05-1.31), and unspecified OA (OR = 1.21, 95% CI: 1.11-1.31). Additionally, per SD increment in calcium decreases the risk of localized OA (OR = 0.83, 95% CI: 0.69-0.98).

CONCLUSIONS

Genetically high zinc and copper status were positively associated with OA, but not with RA. Given the modifiable nature of circulating mineral status, these findings warrant further investigation for OA prevention strategies.

Effects of hepatitis B vaccine boosters in different levels of epidemic areas on anti-HBs-negative children after primary vaccination

Introduction. The widespread of hepatitis B virus is a severe global public problem, and the infant hepatitis B vaccine has been proved effective. But the failure of the immune response was reported in studies, and boosters were recommended. There were few studies about the effect of hepatitis B vaccine boosters in different levels of the epidemic area.Hypothesis. Booster immunization is recommended because there may be a lack of immunization in infants vaccinated with the hepatitis B vaccine. In order to verify the effectiveness of booster immunization, this study hypothesized that it worked well in different levels of endemic areas.Aim. To evaluate the effects of hepatitis B vaccine boosters on children from the areas with different prevalence of hepatitis B whose hepatitis B surface antibody (anti-HBs) were negative (<10 mIU ml^-1).Methodology. A total of 940 children were initially enrolled in screening; however, 421 were excluded. The participants were divided into three groups according to the different areas they come from: group I, low epidemic area; group II, middle epidemic area; and group III, high epidemic area. In total, 519 subjects were administered three doses of booster hepatitis B vaccine (0-1-6 months, 10 µg). The antibody titre changes were examined at four time points: 1 month after dose 1, 1 month, 1 year and 5 years after dose 3.Results. The protective seroconversion rates in three groups were 96.30, 97.16, 96.63% at 1 month after dose 1, and 100.00, 100.00, 100.00% at 1 month after dose 3, and 97.79, 100.00, 98.50% at 1 year after dose 3, and 90.77, 93.67, 93.59% at 5 years after dose 3 (P>0.05).Conclusions. This study demonstrates that three doses of booster vaccination have a longtime effect, no matter whether it is in low, middle or high prevalence areas in which subjects live.

Cellular viability and death biomarkers enables the evaluation of ocular irritation using the bovine corneal opacity and permeability assay

The BCOP assay is used in the identification of chemicals that cause no ocular irritation or serious damage. However, this method has not been found to adequately discriminate between mild from moderate ocular irritation (category 2A/2B), based upon the animal data. In this study, we aimed to establish methods for discerning ocular irritation by chemicals. We used the BCOP assay and the fluorescence staining methods based on biomarkers for cellular viability and death. The potential for ocular irritation by 12 chemicals from different UN GHS categories was assessed by the BCOP assay. Cryosections of bovine corneas were obtained. The necrotic nucleus was TUNEL labeled, cytoplasmic f-actin was stained by phalloidin while the nucleus was stained by DAPI. The depth of injury (DOI) was then measured. According to BCOP assay, in vivo data of Draize eye test and DOI, the results showed that category NC irritants caused ≤ 10 % epithelial DOI, irritants of category 2B caused >10 % epithelial DOI and showed no stromal damage, while category 2A showed damage to the stroma. Based on these results, the GHS prediction model could distinguish between GHS 2A and 2B. Authenticating the viability of BCOP by DOI measurements can provide a more reliable basis for classifying ocular irritants.

Ultra-low-dose CT reconstructed with ASiR-V using SmartmA for pulmonary nodule detection and Lung-RADS classifications compared with low-dose CT

AIM

To evaluate the accuracy of ultra-low-dose computed tomography (ULDCT) with ASiR-V using a noise index (SmartmA) for pulmonary nodule detection and Lung CT Screening Reporting And Data System (Lung-RADS) classifications compared with low-dose CT (LDCT).

MATERIALS AND METHODS

Two-hundred and ten patients referred for lung cancer screening underwent conventional chest LDCT (0.80 ± 0.28 mSv) followed immediately by ULDCT (0.16 ± 0.03 mSv). ULDCT was scanned using 120 kV/SmartmA with a noise index of 28 HU and reconstructed with ASiR-V70%. The types and diameters of all nodules were recorded. The attenuation of pure ground-glass nodules (pGGNs) was measured on LDCT. All nodules were further classified using Lung-RADS. Sensitivities of nodule detection on ULDCT were analysed using LDCT as the reference standard. Logistic regression was used to establish a prediction model for the sensitivity of nodules.

RESULTS

LDCT revealed 362 nodules and the overall sensitivity on ULDCT was 90.1%. The sensitivity for solid nodules (SNs) of ≥1 mm diameter was 96.6% (228/236) and 100% (26/26) for SNs of ≥6 mm diameter. For pGGNs of ≥6 mm, the overall sensitivity was 93% (40/43) and 100% (29/29) for nodules with a attenuation value -700 HU or more. The agreement of Lung-RADS classification between two scans was good. On logistic regression, diameter was the only independent predictor for sensitivity of SNs (p<0.05). Diameter and attenuation value were predictors for pGGNs (p<0.05).

CONCLUSION

ULDCT with ASiR-V using SmartmA is suitable for lung-cancer screening in people with a BMI ≤35 kg/m² as it has a low radiation dose of 0.16 mSv, high sensitivity for nodule detection and good performance of Lung-RADS classifications.

A COVID-19 Risk Assessment Decision Support System for General Practitioners: Design and Development Study

BACKGROUND

The coronavirus disease (COVID-19) has become an urgent and serious global public health crisis. Community engagement is the first line of defense in the fight against infectious diseases, and general practitioners (GPs) play an important role in it. GPs are facing unique challenges from disasters and pandemics in delivering health care. However, there is still no suitable mobile management system that can help GPs collect data, dynamically assess risks, and effectively triage or follow-up with patients with COVID-19.

OBJECTIVE

The aim of this study is to design, develop, and deploy a mobile-based decision support system for COVID-19 (DDC19) to assist GPs in collecting data, assessing risk, triaging, managing, and following up with patients during the COVID-19 outbreak.

METHODS

Based on the actual scenarios and the process of patients using health care, we analyzed the key issues that need to be solved and designed the main business flowchart of DDC19. We then constructed a COVID-19 dynamic risk stratification model with high recall and clinical interpretability, which was based on a multiclass logistic regression algorithm. Finally, through a 10-fold cross-validation to quantitatively evaluate the risk stratification ability of the model, a total of 2243 clinical data consisting of 36 dimension clinical features from fever clinics were used for training and evaluation of the model.

RESULTS

DDC19 is composed of three parts: mobile terminal apps for the patient-end and GP-end, and the database system. All mobile terminal devices were wirelessly connected to the back end data center to implement request sending and data transmission. We used low risk, moderate risk, and high risk as labels, and adopted a 10-fold cross-validation method to evaluate and test the COVID-19 dynamic risk stratification model in different scenarios (different dimensions of personal clinical data accessible at an earlier stage). The data set dimensions were (2243, 15) when only using the data of patients' demographic information, clinical symptoms, and contact history; (2243, 35) when the results of blood tests were added; and (2243, 36) after obtaining the computed tomography imaging results of the patient. The average value of the three classification results of the macro-area under the curve were all above 0.71 in each scenario.

CONCLUSIONS

DCC19 is a mobile decision support system designed and developed to assist GPs in providing dynamic risk assessments for patients with suspected COVID-19 during the outbreak, and the model had a good ability to predict risk levels in any scenario it covered.

[Effect of pretreatment serum LDH and ALP levels on the prognosis of patients with nasopharyngeal carcinoma]

Objective:To investigate the effects of serum lactate dehydrogenase (LDH) and serum alkaline phosphatase (ALP) levels on the prognosis of patients with nasopharyngeal carcinoma (NPC) before treatment.Method:Three hundred and thirty nine NPC cases, who were firstly treated in our hospital from April 2006 to October 2008, were enrolled in our study. Association of overall survival (OS) rate and disease-free survival (DFS) rate with clinical characteristics (age, gender, Tclassification, Nclassification, clinicalstage, radio therapy methods, radio therapy dose, the levels of pretreatment serum LDH) were evaluated using univariate and multivariate analysis methods.Result:Univariate analysis showed that age, clinical stage, pretreatment LDH level were significantly associated with OS and DFS of NPC. And multivariate analysis revealed that age, clinical stage and pretreatment LDH level were independent factors for OS and DFS.Conclusion:Age, clinical stage and the levels of pretreatment LDH level may be independent prognostic factorsto predict recurrence and death of NPC.

Near-Term Decrease in Brain Volume following Mild Traumatic Injury Is Detectible in the Context of Preinjury Volumetric Stability: Neurobiologic Insights from Analysis of Historical Imaging Examinations

BACKGROUND AND PURPOSE

Neurodegeneration after mild traumatic brain injury may manifest as decreasing regional brain volume that evolves from months to years following mild traumatic brain injury and is associated with worse clinical outcomes. We hypothesized that quantitative brain volume derived from CT of the head, performed for clinical indications during routine care, would change with time and provide insights into the putative neuroinflammatory response to mild traumatic brain injury.

MATERIALS AND METHODS

We searched the electronic medical record of our institution for NCCTs of the head performed in patients with mild traumatic brain injury and included those who also underwent NCCTs of the head 1 month to 1 year before and after mild traumatic brain injury for an indication unrelated to trauma. Controls underwent 3 sequential NCCTs of the head with indications unrelated to trauma. The whole-brain and intracranial volume groups were computed using ITK-SNAP. Brain volumes normalized to intracranial volumes were compared across time points using the Wilcoxon signed-rank test.

RESULTS

We identified 48 patients from 2005 to 2015 who underwent NCCTs of the head in the emergency department for mild traumatic brain injury and had NCCTs of the head performed both before and after mild traumatic brain injury. Median normalized brain volumes significantly decreased on the follow-up study post-mild traumatic brain injury (0.86 versus 0.84, P < .001) and were similar compared with pre-mild traumatic brain injury studies (0.87 versus 0.86, P = .927). There was no significant difference between normalized brain volumes in the 48 controls.

CONCLUSIONS

A decrease in brain volume following mild traumatic brain injury is detectable on CT and is not seen in similar patients with non-mild traumatic brain injury during a similar timeframe. Given the stability of brain volume before mild traumatic brain injury, CT volume loss may represent the subtle effects of neurodegeneration.

Autism-associated Dyrk1a truncation mutants impair neuronal dendritic and spine growth and interfere with postnatal cortical development

Autism is a prevailing neurodevelopmental disorder with a large genetic/genomic component. Recently, the dual-specificity tyrosine-(Y)-phosphorylation-regulated kinase 1 A (DYRK1A) gene was implicated as a risk factor for autism spectrum disorder (ASD). We identified five DYRK1A variants in ASD patients and found that the dose of DYRK1A protein has a crucial role in various aspects of postnatal neural development. Dyrk1a loss of function and gain of function led to defects in dendritic growth, dendritic spine development and radial migration during cortical development. Importantly, two autism-associated truncations, R205X and E239X, were shown to be Dyrk1a loss-of-function mutants. Studies of the truncated Dyrk1a mutants may provide new insights into the role of Dyrk1a in brain development, as well as the role of Dyrk1a loss of function in the pathophysiology of autism.

Outcomes of Pharmacomechanical Catheter-directed Thrombolysis for Acute and Subacute Inferior Vena Cava Thrombosis: A Retrospective Evaluation in a Single Institution

OBJECTIVE/BACKGROUND

The objective was to assess the mid-term results of pharmacomechanical catheter-directed thrombolysis (PCDT) for symptomatic acute and subacute inferior vena cava (IVC) thrombosis; the risk factors of early thrombosis recurrence and iliocaval patency were also evaluated.

METHODS

From January 2010 to December 2015, 54 patients (33 men; mean age 47.1 years) with symptomatic acute and subacute IVC thrombosis were treated with PCDT. Primary technical success (clot lysis ≥ 50% after PCDT), stent-assisted technical success (residual stenosis < 30% after stenting), clinical success (freedom from thrombosis recurrence within 30 days), complications, frequency of post-thrombotic syndrome (PTS; Villalta score ≥ 5), and iliocaval patency were recorded at follow-up evaluation. A multivariate regression model was used to determine predictors of early thrombosis reoccurrence and iliocaval patency.

RESULTS

The primary technical success and the stent-assisted technical success were 63% (n = 34/54) and 100% (n = 54/54) respectively. There were 11 patients (20%) with immediate recurrent thrombosis requiring repeat PCDT. Minor bleeding complications occurred in seven patients, and one patient with major bleeding needed a blood transfusion. The occurrence of PTS at a mean of 26 months (range 1-60 months) was 13% (7/54). The 3-year primary and secondary iliocaval patency was 63% and 81%, respectively. On multivariate analysis, active malignancy was predictive of immediate IVC thrombosis recurrence (hazard ratio [HR] 5.8, 95% confidence interval [CI] 1.7-19.8; p = .01), whereas the pre-existing filter played a protective role against iliocaval re-occlusion (HR 0.3, 95% CI 0.1-0.8; p = .01).

CONCLUSIONS

PCDT is safe and effective in managing symptomatic acute and subacute IVC thrombosis. Active malignancy is predictor of thrombosis re-occurrence, whereas the presence of a filter is associated with a higher rate of iliocaval patency at mid-term follow-up.

Mathematical modelling of growth of Listeria monocytogenes in raw chilled pork

The aim of this study was to analyse the growth kinetics of Listeria monocytogenes in naturally contaminated chilled pork. A cocktail of 26 meat-borne L. monocytogenes was inoculated to raw or sterile chilled pork to observe its growth at 4, 10, 16, 22 and 28°C respectively. The growth data were fitted by the Baranyi model and Ratkowsky square-root model. Results showed that the Baranyi model and Ratkowsky square-root model could describe the growth characteristics of L. monocytogenes at different temperatures reasonably well in raw chilled pork (1·0 ≤ Bf ≤ Af ≤ 1·1). Compared with the growth of L. monocytogenes in sterile chilled pork, the background microflora had no impact on the growth parameters of L. monocytogenes, except for the lag phase at low temperature storage. The microbial predictive models developed in this study can be used to predict the growth of L. monocytogenes during natural spoilage, and construct quantitative risk assessments in chilled pork.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study simulated the actual growth of Listeria monocytogenes in chilled pork to the maximum extent, and described its growth characteristics of L. monocytogenes during natural spoilage. This study showed that the background microflora had no impact on the growth parameters of L. monocytogenes, except for the lag phase at low temperature storage. The models developed in this study can be used to predict the growth of L. monocytogenes during refrigerated storage.

Apocynin Attenuates Cerebral Infarction after Transient Focal Ischaemia in Rats

This study investigated whether inhibition of reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase attenuates cerebral infarction after transient focal ischaemia in rats. Focal ischaemia (1.5 h) was produced in male Sprague-Dawley rats (250 − 280 g) by middle cerebral artery occlusion. Some rats also received treatment with 50 mg/kg apocynin, a NADPH oxidase inhibitor, by intraperitoneal injection 30 min prior to reperfusion. Two hours after reperfusion, brains were harvested to measure NADPH oxidase activity and superoxide levels. After 24 h, the remaining brains were harvested to investigate infarct size. NADPH oxidase activity and superoxide level were all augmented 2 h after reperfusion compared with controls. Apocynin treatment significantly reduced NADPH oxidase activity and superoxide levels. Cerebral infarct size was significantly smaller in the apocynin-treated group compared with those undergoing ischaemia/reperfusion alone. These results indicate that inhibition of NADPH oxidase attenuates cerebral infarction after transient focal ischaemia in rats, suggesting that inhibition of NADPH oxidase may provide a therapeutic strategy for ischaemic stroke.

Detecting dispersed duplications in high-throughput sequencing data using a database-free approach

MOTIVATION

Dispersed duplications (DDs) such as transposon element insertions and copy number variations are ubiquitous in the human genome. They have attracted the interest of biologists as well as medical researchers due to their role in both evolution and disease. The efforts of discovering DDs in high-throughput sequencing data are currently dominated by database-oriented approaches that require pre-existing knowledge of the DD elements to be detected.

RESULTS

We present DD_DETECTION, a database-free approach to finding DD events in high-throughput sequencing data. DD_DETECTION is able to detect DDs purely from paired-end read alignments. We show in a comparative study that this method is able to compete with database-oriented approaches in recovering validated transposon insertion events. We also experimentally validate the predictions of DD_DETECTION on a human DNA sample, showing that it can find not only duplicated elements present in common databases but also DDs of novel type.

AVAILABILITY AND IMPLEMENTATION

The software presented in this article is open source and available from https://bitbucket.org/mkroon/dd_detection.

Fyn-phosphorylated PIKE-A binds and inhibits AMPK signaling, blocking its tumor suppressive activity

The AMP-activated protein kinase, a key regulator of energy homeostasis, has a critical role in metabolic disorders and cancers. AMPK is mainly regulated by cellular AMP and phosphorylation by upstream kinases. Here, we show that PIKE-A binds to AMPK and blocks its tumor suppressive actions, which are mediated by tyrosine kinase Fyn. PIKE-A directly interacts with AMPK catalytic alpha subunit and impairs T172 phosphorylation, leading to repression of its kinase activity on the downstream targets. Mutation of Fyn phosphorylation sites on PIKE-A, depletion of Fyn, or pharmacological inhibition of Fyn blunts the association between PIKE-A and AMPK, resulting in loss of its inhibitory effect on AMPK. Cell proliferation and oncogenic assays demonstrate that PIKE-A antagonizes tumor suppressive actions of AMPK. In human glioblastoma samples, PIKE-A expression inversely correlates with the p-AMPK levels, supporting that PIKE-A negatively regulates AMPK activity in cancers. Thus, our findings provide additional layer of molecular regulation of the AMPK signaling pathway in cancer progression.

Characteristics and clinical significance of lymph node metastases near the recurrent laryngeal nerve from thoracic esophageal carcinoma

This study aimed to evaluate the characteristics of lymph node (LN) metastases from thoracic esophageal carcinoma near the recurrent laryngeal nerve and the influence of these metastases on patient prognosis and to determine the reasonable regional LN dissection range. The clinical data from 120 patients who underwent resection for thoracic esophageal carcinoma were analyzed retrospectively. LN metastases near the recurrent laryngeal nerve were detected in 34.2% of the cases, and the metastasis rates in the left and right LNs near the recurrent laryngeal nerve were 20.8 and 15.8%, respectively. The primary tumor site (metastasis rates for esophageal cancer in the upper thoracic segment vs chest or lower thoracic segment: 60.0 vs 40.3 or 15.8%, respectively; P < 0.01), tumor differentiation (poorly differentiated vs well differentiated or differentiated: 56.0 vs 22.0 or 35.6%, respectively; P < 0.05), and tumor invasion depth (T3 and T4 vs T1 and T2: 42.9 and 50.0% vs 8.33 and 14.3%, respectively; P < 0.01) were factors that significantly influenced LN metastasis near the recurrent laryngeal nerve LN metastases near the recurrent laryngeal nerve were associated with cervical LN metastasis. The 3-year survival rate of patients with LN metastasis near the recurrent laryngeal nerve was much lower than that of patients with other LN metastases (29.3 vs 58.2%; P < 0.05). In thoracic esophageal carcinoma cases, LNs near the recurrent laryngeal nerve should be resected. This could improve the patient prognosis and reduce the incidence of postoperative local recurrence.

Merlin sumoylation is required for its tumor suppressor activity

Merlin, encoded by the Neurofibromatosis 2 (NF2) gene, is a multifunctional tumor suppressor that integrates and regulates extracellular cues and intracellular signaling pathways, both at the plasma membrane and in the nucleus, to control cell proliferation, migration and invasion. Molecular mechanisms regulating merlin's tumor-suppressive activity have not been clearly defined. Here we report that merlin can be sumoylated on Lysine residue (K76) in vitro and in vivo. Sumoylation mediates merlin's intramolecular and intermolecular binding activities and regulates its cytoplasm/nucleus trafficking. Interestingly, sumoylation of merlin is regulated by its phosphorylation via Akt and PAK2 kinases. Mutation of K76 into arginine (R) abolishes its sumoylation, disrupts merlin cortical cytoskeleton residency and attenuates its stability. Using a K76R mutant merlin in a subcutaneous U87MG xenograft model, we demonstrate that merlin sumoylation is required for tumor-suppressive activity. Taken together, our findings indicate that merlin is sumoylated and that this post-translational modification is essential for tumor suppression.

Acinus-provoked protein kinase C δ isoform activation is essential for apoptotic chromatin condensation

Histone H2B phosphorylation tightly correlates with chromatin condensation during apoptosis. The caspase-cleaved acinus (apoptotic chromatin condensation inducer in the nucleus) provokes chromatin condensation in the nucleus, but the molecular mechanism accounting for this effect remains elusive. Here, we report that the active acinus p17 fragment initiates H2B phosphorylation and chromatin condensation by activating protein kinase C delta isoform (PKC-delta). We show that p17 binds to both Mst1 and PKC-delta, which is upregulated by apoptotic stimuli, enhancing their kinase activities. Acinus mutant susceptible to degradation elicits stronger chromatin condensation and higher H2B phosphorylation than wild-type acinus. Dominant-negative PKC-delta but not Mst1 robustly blocks acinus-initiated H2B phosphorylation. Surprisingly, depletion of Mst1 triggers caspase-3 activation, provoking H2B phosphorylation through activating PKC-delta. Further, acinus-elicited H2B phosphorylation and chromatin condensation are abrogated in PKC-delta-deficient mouse embryonic fibroblast cells and siRNA-knocked down PC12 cells. Thus, PKC-delta but not Mst1 acts as a physiological downstream kinase of acinus in promoting H2B phosphorylation and chromatin condensation.

Structural biology of RNA silencing and its functional implications

We outline structure-function contributions from our laboratories on protein-RNA recognition events that monitor siRNA length, 5 -phosphate and 2-nucleotide 3 overhangs, as well as the architecture of Argonaute, its externally bound siRNA complex, and Argonaute-based models involving guide-strand-mediated mRNA binding, cleavage, and release.

Akt phosphorylation of zyxin mediates its interaction with acinus-S and prevents acinus-triggered chromatin condensation

Zyxin, a focal adhesion molecule, contains LIM domains and shuttles between the cytoplasm and the nucleus. Nuclear zyxin promotes cardiomyocyte survival, which is mediated by nuclear-activated Akt. However, the molecular mechanism of how zyxin antagonizes apoptosis remains elusive. Here, we report that zyxin binds to acinus-S, a nuclear speckle protein inducing apoptotic chromatin condensation after cleavage by caspases, and prevents its apoptotic action, which is regulated by Akt. Akt binds and phosphorylates zyxin on serine 142, leading to its association with acinus. Interestingly, 14-3-3gamma, but not zeta isoform selectively, triggers zyxin nuclear translocation, which is Akt phosphorylation dependent. Zyxin is also a substrate of caspases, but Akt phosphorylation is unable to prevent its apoptotic cleavage. Expression of zyxin S142D, a phosphorylation mimetic mutant, diminishes acinus proteolytic cleavage and chromatin condensation; by contrast, wild-type zyxin or unphosphorylated S142A mutant fails. Thus, Akt regulates zyxin/acinus complex formation in the nucleus, contributing to suppression of apoptosis.

PIKE-A is a proto-oncogene promoting cell growth, transformation and invasion

PIKE-A (phosphoinositide 3-kinases (PI 3)-kinase enhancer) is a ubiquitously expressed GTPase, which binds to and enhances protein kinase B (Akt) kinase activity in a guanine nucleotide-dependent manner. PIKE-A is one of the components of the CDK4 amplicon that is amplified in numerous human cancers. However, whether PIKE-A itself can mediate cell transformation, proliferation and migration remains unknown. Here, we show that PIKE-A is overexpressed in various human cancer samples, escalates U87MG glioblastoma invasion and provokes NIH3T3 cell transformation. Overexpression of wild-type (WT) PIKE-A enhances NIH3T3 and U87MG cell growth, which is further increased by cancer cell-derived PIKE-A active mutants. In contrast, both the dominant-negative mutant and the phosphoinositide lipids interaction-defective mutant antagonize cell proliferation. Moreover, PIKE-A and its active and inactive mutants similarly enhance or antagonize U87MG cell survival and invasion, and their ability to do so is coupled with the catalytic effect they have on Akt activation. Furthermore, PIKE-A WT and its active mutants significantly elicit NIH3T3 cell transformation. Thus, our findings support the concept that PIKE-A acts as a proto-oncogene, promoting cell transformation through Akt activation.

Src-family tyrosine kinase fyn phosphorylates phosphatidylinositol 3-kinase enhancer-activating Akt, preventing its apoptotic cleavage and promoting cell survival

Phosphatidylinositol 3-kinase enhancer-activating Akt (PIKE-A) binds Akt and upregulates its kinase activity, preventing apoptosis. PIKE-A can be potently phosphorylated on tyrosine residues 682 and 774, leading to its resistance to caspase cleavage. However, the upstream tyrosine kinases responsible for PIKE-A phosphorylation and subsequent physiological significance remain unknown. Here, we show that PIKE-A can be cleaved by the active apoptosome at both D474 and D592 residues. Employing fyn-deficient mouse embryonic fibroblast cells and tissues, we demonstrate that fyn is essential for phosphorylating PIKE-A and protects it from apoptotic cleavage. Active but not kinase-dead fyn interacts with PIKE-A and phosphorylates it on both Y682 and Y774 residues. Tyrosine phosphorylation in PIKE-A is required for its association with active fyn but not for Akt. Mutation of D into A in PIKE-A protects it from caspase cleavage and promotes cell survival. Thus, this finding provides a molecular mechanism accounting for the antiapoptotic action of src-family tyrosine kinase.

Multicenter evaluation of a new screening test that detects Clostridium difficile in fecal specimens

Clostridium difficile causes approximately 25% of nosocomial antibiotic-associated diarrheas and most cases of pseudomembranous colitis. We evaluated C. DIFF CHEK, a new screening test that detects glutamate dehydrogenase of C. difficile. Our results showed that this test was comparable to PCR in sensitivity and specificity and outperformed bacterial culture.

A model to estimate the optimal sample size for microbiological surveys

Estimating optimal sample size for microbiological surveys is a challenge for laboratory managers. When insufficient sampling is conducted, biased inferences are likely; however, when excessive sampling is conducted valuable laboratory resources are wasted. This report presents a statistical model for the estimation of the sample size appropriate for the accurate identification of the bacterial subtypes of interest in a specimen. This applied model for microbiology laboratory use is based on a Bayesian mode of inference, which combines two inputs: (ii) a prespecified estimate, or prior distribution statement, based on available scientific knowledge and (ii) observed data. The specific inputs for the model are a prior distribution statement of the number of strains per specimen provided by an informed microbiologist and data from a microbiological survey indicating the number of strains per specimen. The model output is an updated probability distribution of strains per specimen, which can be used to estimate the probability of observing all strains present according to the number of colonies that are sampled. In this report two scenarios that illustrate the use of the model to estimate bacterial colony sample size requirements are presented. In the first scenario, bacterial colony sample size is estimated to correctly identify Campylobacter amplified restriction fragment length polymorphism types on broiler carcasses. The second scenario estimates bacterial colony sample size to correctly identify Salmonella enterica serotype Enteritidis phage types in fecal drag swabs from egg-laying poultry flocks. An advantage of the model is that as updated inputs from ongoing surveys are incorporated into the model, increasingly precise sample size estimates are likely to be made.

Sustained activation of p34(cdc2) is required for noscapine-induced apoptosis

Mitotic arrest and subsequent apoptosis has been observed in many types of cells treated with anti-microtubule agents. However, the molecular mechanisms underlying the two events as well as their relationship are not well understood; on the contrary, there has been increasing evidence indicating that anti-microtubule agents might induce apoptosis via signaling pathways independent of mitosis. In this study, we found that apoptosis induced by noscapine, an anti-microtubule drug previously shown to cause both mitotic arrest and apoptotic cell death, was blocked by inhibiting p34(cdc2) activity with olomoucine in FM3A murine mammary carcinoma cells or by reducing the level and activity of p34(cdc2) in a mutant cell line FT210 derived from FM3A. Furthermore, transfection of the mutant FT210 cells with wild-type p34(cdc2) restored their ability to undergo mitotic arrest and then apoptosis in response to noscapine. Thus, we conclude that sustained activation of the p34(cdc2) kinase during mitotic arrest is required for subsequent apoptosis induced by noscapine, establishing a link between the two events.

Effects of charged amino-acid mutation on the solution structure of cytochrome b(5) and binding between cytochrome b(5) and cytochrome c

The solution structure of oxidized bovine microsomal cytochrome b(5) mutant (E48, E56/A, D60/A) has been determined through 1524 meaningful nuclear Overhauser effect constraints together with 190 pseudocontact shift constraints. The final family of 35 conformers has rmsd values with respect to the mean structure of 0.045+/-0.009 nm and 0.088+/-0.011 nm for backbone and heavy atoms, respectively. A characteristic of this mutant is that of having no significant changes in the whole folding and secondary structure compared with the X-ray and solution structures of wild-type cytochrome b(5). The binding of different surface mutants of cytochrome b(5) with cytochrome c shows that electrostatic interactions play an important role in maintaining the stability and specificity of the protein complex formed. The differences in association constants demonstrate the electrostatic contributions of cytochrome b(5) surface negatively charged residues, which were suggested to be involved in complex formation in the Northrup and Salemme models, have cumulative effect on the stability of cyt c-cyt b(5) complex, and the contribution of Glu48 is a little higher than that of Glu44. Moreover, our result suggests that the docking geometry proposed by Northrup, which is involved in the participation of Glu48, Glu56, Asp60, and heme propionate of cytochrome b(5), do occur in the association between cytochrome b(5) and cytochrome c.

Creation of cell surface-engineered yeast that display different fluorescent proteins in response to the glucose concentration

We have successfully created a novel yeast strain able to monitor changes in environmental conditions by displaying either green fluorescent protein (GFP) from Aequorea victoria or blue fluorescent protein (BFP), a variant of GFP, on its cell surface as a visible reporter. For the display of these fluorescent proteins on the cell surface of Saccharomyces cerevisiase, our cell-surface-engineering system was utilized. The GAPDH promoter, which is active in the presence of glucose, and the UPR-ICL promoter from Candida tropicalis, which starts to function in the presence of a reduced level of glucose, were employed simultaneously to express the GFP-encoding gene and the BFP-encoding gene, respectively. This cell-surface-engineered yeast strain emitted green fluorescence from the cell surface when sufficient glucose was present in the medium, and blue fluorescence from the same cell surface when the glucose in the medium was consumed. The fluorescent proteins displayed on the cell surface using the different promoters enabled us to monitor the concentrations of intra- and/or extracellular glucose that regulated activation or inactivation of the promoters. This novel yeast strain could facilitate the computerized control of various bioprocesses measuring emitted fluorescence.

GRAB: a physiologic guanine nucleotide exchange factor for Rab3A, which interacts with inositol hexakisphosphate kinase

Diphosphoinositol-pentakisphosphate (InsP7) and bis-diphosphoinositol tetrakisphosphate (InsP8) possess pyrophosphate bonds. InsP7 is formed from inositol hexakisphosphate (InsP6) by recently identified InsP6 kinases designated InsP6K1 and InsP6K2. We now report the identification, cloning, and characterization of a novel protein, GRAB (guanine nucleotide exchange factor for Rab3A), which interacts with both InsP6K1 and Rab3A, a Ras-like GTPase that regulates synaptic vesicle exocytosis. GRAB is a physiologic GEF (guanine nucleotide exchange factor) for Rab3A. Consistent with a role of Rab3A in synaptic vesicle exocytosis, GRAB regulates depolarization-induced release of dopamine from PC12 cells and nicotinic agonist-induced hGH release from bovine adrenal chromaffin cells. The association of InsP6K1 with GRAB fits with a role for InsP7 in vesicle exocytosis.

Self-association reaction of denatured staphylococcal nuclease fragments characterized by heteronuclear NMR

The self-association reaction of denatured staphylococcal nuclease fragments, urea-denatured G88W110, containing residues 1-110 and mutation G88W, and physiologically denatured 131-residue Delta 131 Delta, have been characterized by NMR at close to neutral pH. The two fragments differ in the extent and degree of association due to the different sequence and experimental conditions. Residues 13-39, which show significant exchange line broadening, constitute the main association interface in both fragments. A second weak association region was identified involving residues 79-105 only in the case of urea-denatured G88W110. For residues involved in the association reaction, significant suppression of the line broadening and small but systematic chemical shift variation of the amide protons were observed as the protein concentration decreased. The direction of chemical shift change suggests that the associated state adopts mainly beta-sheet-like conformation, and the beta-hairpin formed by strands beta 2 and beta 3 is native-like. The apparent molecular size obtained by diffusion coefficient measurements shows a weak degree of association for Delta 131 Delta below 0.4 mM protein concentration and for G88W110 in 4 M urea. In both cases the fragments are predominantly in the monomeric state. However, the weak association reaction can significantly influence the transverse relaxation of residues involved in the association reaction. The degree of association abruptly increases for Delta 131 Delta above 0.4 mM concentration, and it is estimated to form a 4 to 8 mer at 2 mM. It is proposed that the main region involved in association forms the core structure, with the remainder of residues largely disordered in the associated state. Despite the obvious influence of the association reaction on the slow motion of the backbone, the restricted mobility on the nanosecond timescale around the region of strand beta 5 is essentially unaffected by the association reaction and degree of denaturation.

FKBP12, the 12-kDa FK506-binding protein, is a physiologic regulator of the cell cycle

FKBP12, the 12-kDa FK506-binding protein, is a ubiquitous abundant protein that acts as a receptor for the immunosuppressant drug FK506, binds tightly to intracellular calcium release channels and to the transforming growth factor beta (TGF-beta) type I receptor. We now demonstrate that cells from FKBP12-deficient (FKBP12(-/-)) mice manifest cell cycle arrest in G(1) phase and that these cells can be rescued by FKBP12 transfection. This arrest is mediated by marked augmentation of p21(WAF1/CIP1) levels, which cannot be further augmented by TGF-beta1. The p21 up-regulation and cell cycle arrest derive from the overactivity of TGF-beta receptor signaling, which is normally inhibited by FKBP12. Cell cycle arrest is prevented by transfection with a dominant-negative TGF-beta receptor construct. TGF-beta receptor signaling to gene expression can be mediated by SMAD, p38, and ERK/MAP kinase (extracellular signal-regulated kinase/mitogen-activated protein kinase) pathways. SMAD signaling is down-regulated in FKBP12(-/-) cells. Inhibition of ERK/MAP kinase fails to affect p21 up-regulation. By contrast, activated phosphorylated p38 is markedly augmented in FKBP12(-/-) cells and the p21 up-regulation is prevented by an inhibitor of p38. Thus, FKBP12 is a physiologic regulator of cell cycle acting by normally down-regulating TGF-beta receptor signaling.

Statistical assessment of violations of water quality standards under Section 303(d) of the clean water act

Section 303(d) of the Clean Water Act requires states to assess the condition of their waters and to implement plans to improve the quality of waters identified as impaired. U.S. Environmental Protection Agency guidelines require a stream segment to be listed as impaired when greater than 10% of the measurements of water quality conditions exceed numeric criteria. This can be termed a "raw score" assessment approach. Water quality measurements are samples taken from a population of water quality conditions. Concentrations of pollutants vary naturally, measurement errors may be made, and occasional violations of a standard may be tolerable. Therefore, it is reasonable to view the assessment process as a statistical decision problem. Assessment of water quality conditions must be cognizant of the possibility of type I (a false declaration of standards violation) and type II (a false declaration of no violation) errors. The raw score approach is shown to have a high type I error rate. Alternatives to the raw score approach are the Binomial test and the Bayesian Binomial approach. These methods use the same information to make decisions but allow for control of the error rates. The two statistical methods differ based on consideration of prior information about violation. Falsely concluding that a water segment is impaired results in unnecessary planning and pollution control implementation costs. On the other hand, falsely concluding that a segment is not impaired may pose a risk to human health or to the services of the aquatic environment. An approach that recognizes type I and type II error in the water quality assessment process is suggested.

Pike. A nuclear gtpase that enhances PI3kinase activity and is regulated by protein 4.1N

While cytoplasmic PI3Kinase (PI3K) is well characterized, regulation of nuclear PI3K has been obscure. A novel protein, PIKE (PI3Kinase Enhancer), interacts with nuclear PI3K to stimulate its lipid kinase activity. PIKE encodes a 753 amino acid nuclear GTPase. Dominant-negative PIKE prevents the NGF enhancement of PI3K and upregulation of cyclin D1. NGF treatment also leads to PIKE interactions with 4.1N, which has translocated to the nucleus, fitting with the initial identification of PIKE based on its binding 4.1N in a yeast two-hybrid screen. Overexpression of 4.1N abolishes PIKE effects on PI3K. Activation of nuclear PI3K by PIKE is inhibited by the NGF-stimulated 4.1N translocation to the nucleus. Thus, PIKE physiologically modulates the activation by NGF of nuclear PI3K.

Improvement of vitamin B(12) fermentation by reducing the inhibitory metabolites by cell recycle system and a mixed culture

The major problem in vitamin B(12) production using Propionibacterium is the growth inhibition of the cell due to the accumulation of inhibitory metabolites such as propionic acid and acetic acid. In the present paper, we considered several approaches of controlling the propionic acid concentration at low level. Namely: (1) the periodic cultivation of Propionibacterium where dissolved oxygen (DO) concentration was alternatively changed between 0 and 1ppm; (2) cell recycle system using hollow fiber module; and (3) mixed culture using Propionibacterium and Ralstonia eutropha where the latter microorganism assimilates the propionic acid produced by the former. It was found that the productivity of vitamin B(12) was the highest for the cell recycle system, while if the performance was evaluated based on the amount of vitamin B(12) produced per medium used, the mixed culture system gave the far highest value.

[Effect of qiongyugao on the action of DDP in inhibiting the division of GLC-82 cell strain in vitro]

OBJECTIVE

To observe the effect of Qiongyugao (QYG) on the action of DDP in inhibiting the division of GLC-82 cell strain in vitro.

METHODS

The method of serum pharmacology was used in observing the morphological change of the cancer cells. By accounting the number of the live cells of each day during 6 days respectively, the growth curve was drawn up. The effects of the three groups on the cancer cells apoptosis of GLC-82 cell strain were analysed by FACS. RESULLTS: The growth of the cancer cells in control group (normal saline) was much better than the other two groups; in chemical therapy group (DDP), the number of the live cells almost kept steady; the number of the live cells in combined group(DDP plus QYG) became even lower. QYG could enhance the action of DDP in inducing the apoptosis of GLC-82 cells strain remarkably.

CONCLUSION

QYG can enhance the effects of chemotherapy in inhibiting cancer cells division and inducing their apoptosis.