[Global trends in the incidence and prevalence of pneumoconiosis in 204 countries/territories from 1990 to 2019]

Objective: To analyze the changing trend of incidence and prevalence of pneumoconiosis globally, and provide scientific basis for the formulation of health policy. Methods: In June 2022, through the Global Health Data exchange (GHDx) query tool (http: //ghdx.healthdata.org/gbd-results-tool) , the pneumoconiosis incidence and prevalence data was downloaded and organized. Estimated annual percentage change (EAPC) and age-standardized rate (ASR) were used to estimate the trends of pneumoconiosis from 1990 to 2019. EAPC was estimated by linear regression model based on ASR. Results: The overall ASR of the incidence and prevalence of pneumoconiosis decreased from 1990 to 2019, and their EAPCs were-0.85% (95%CI: -1.11%--0.60%) and -0.78% (95%CI: -1.08%--0.49%) . Over the past 30 years, the incidence and prevalence of pneumoconiosis in all SDI areas showed decreasing trends, especially in high SDI areas, their EAPCs were -1.46% (95%CI: -1.76%--1.15%) and -1.99% (95%CI: -2.44%--1.53%) . 110 countries/areas showed increasing trends in age standardized incidence rate (ASIR) , with Iran and Georgia showing the most pronounced upward trend, their EAPCs were 5.32% (95%CI: 4.43%-6.22%) and 4.39% (95%CI: 3.81%-4.97%) . 125 countries/areas showed anincreasing trends in prevalence ASR, with Iran had the fastest rise in prevalence (EAPC=6.40%, 95%CI: 5.33%-7.49%) . Conclusion: Although decreasing trends in the burden of pneumoconiosis are observed globally from 1990 to 2019, but the burden of pneumoconiosis in low-and middle-income countries or regions are still heavy. We need more effective strategies to prevent and reduce the burden of pneumoconiosis.

[Establishment and efficiency test of a clinical prediction model of bronchopulmonary dysplasia associated pulmonary hypertension in very premature infants]

Objective: To develop a risk prediction model for identifying bronchopulmonary dysplasia (BPD) associated pulmonary hypertension (PH) in very premature infants. Methods: This was a retrospective cohort study. The clinical data of 626 very premature infants whose gestational age <32 weeks and who suffered from BPD were collected from October 1st, 2015 to December 31st, 2021 of the Seventh Medical Center of the People's Liberation Army General Hospital as a modeling set. The clinical data of 229 very premature infants with BPD of Hunan Children's Hospital from January 1 st, 2020 to December 31st, 2021 were collected as a validation set for external verification. The very premature infants with BPD were divided into PH group and non PH group based on the echocardiogram after 36 weeks' corrected age in the modeling set and validation set, respectively. Univariate analysis was used to compare the basic clinical characteristics between groups, and collinearity exclusion was carried out between variables. The risk factors of BPD associated PH were further screened out by multivariate Logistic regression, and the risk assessment model was established based on these variables. The receiver operating characteristic (ROC) area under curve (AUC) and Hosmer-Lemeshow goodness-of-fit test were used to evaluate the model's discrimination and calibration power, respectively. And the calibration curve was used to evaluate the accuracy of the model and draw the nomogram. The bootstrap repeated sampling method was used for internal verification. Finally, decision curve analysis (DCA) to evaluate the clinical practicability of the model was used. Results: A total of 626 very premature infants with BPD were included for modeling set, including 85 very premature infants in the PH group and 541 very premature infants in the non PH group. A total of 229 very premature infants with BPD were included for validation set, including 24 very premature infants in the PH group and 205 very premature infants in the non PH group. Univariate analysis of the modeling set found that 22 variables, such as artificial conception, fetal distress, gestational age, birth weight, small for gestational age, 1 minute Apgar score ≤7, antenatal corticosteroids, placental abruption, oligohydramnios, multiple pulmonary surfactant, neonatal respiratory distress syndrome (NRDS)>stage Ⅱ, early pulmonary hypertension, moderate-severe BPD, and hemodynamically significant patent ductus arteriosus (hsPDA) all had statistically significant influence between the PH group and the non PH group (all P<0.05). Antenatal corticosteroids, fetal distress, NRDS >stage Ⅱ, hsPDA, pneumonia and days of invasive mechanical ventilation were identified as predictive variables and finally included to establish the Logistic regression model. The AUC of this model was 0.86 (95%CI 0.82-0.90), the cut-off value was 0.17, the sensitivity was 0.77, and the specificity was 0.84. Hosmer-Lemeshow goodness-of-fit test showed that P>0.05. The AUC for external validation was 0.88, and the Hosmer-Lemeshow goodness-of-fit test suggested P>0.05. Conclusions: A high sensitivity and specificity risk prediction model of PBD associated PH in very premature infants was established. This predictive model is useful for early clinical identification of infants at high risk of BPD associated PH.

[Investigation of a carbon monoxide poisoning accident with a hidden source]

In June 2022, a carbon monoxide poisoning accident with hidden source occurred in a bonded gold/silver wire manufacturing enterprise in Guangzhou, causing 10 people to be poisoned, of which 1 was caused by carbon monoxide poisoning and 9 by carbon monoxide contact reaction. The symptoms were dizziness, fatigue and vomiting. After 5 to 7 h, the saturation of carboxyhemoglobin in finger pulse was 4% to 10%, and the saturation of carboxyhemoglobin in blood gas biochemical analysis was 1.9% to 5.8%. The concentration of carbon monoxide detected in the carbon borne purification plant of the enterprise was 34.46-37.26 mg/m(3). It was judged that the accident was carbon monoxide poisoning caused by carbon monoxide gas being transported to the work post along the gas transmission pipeline due to abnormal operation of the carbon borne purification plant. By investigating the source and cause of poison, this paper provides a warning for the similar process to prevent similar events, and provides a new idea for the identification of chemical poisoning risk. At the same time, it is warned that similar enterprises should fully consider the risk of poisoning under specific circumstances, strengthen equipment maintenance and repair, and prevent the occurrence of similar incidents.

[Value of the monocyte-to-lymphocyte ratio in the prognostic evaluation of hepatitis B-related acute-on-chronic liver failure]

Objective: To investigate the predictive value of the monocyte-to-lymphocyte ratio (MLR) for survival in patients with hepatitis B-related acute-on-chronic liver failure (HBV-ACLF). Methods: 92 cases with HBV-ACLF who were admitted to the General Hospital of Western Theater Command from October 2014 to October 2017 were selected. Clinical indicators were retrospectively collected, and their survival condition was followed up for 90 days, with the end point as death or liver transplantation. MLR levels predictive value among patients after 90 days of involvement was compared by analyzing the differences between the survival and death groups and its correlation with various indicators of liver function for prognosis. Results: 92 cases were included in this study, with a 90-day survival rate of 52% (48/92), and a mortality rate of 48% (44/92). MLR for survival and death groups were 0.520 (0.310, 0.828) and 0.740 (0.440, 1.120), respectively. MLR level was significantly higher in the death than survival group (P<0.05). Receiver operating characteristic curve (ROC) analysis showed that the area under the ROC curve (AUC) and 95% confidence interval for the survival group was 0.640 (0.527-0.754). The cutoff value for MLR was 0.399 at which the sensitivity and specificity were 0.864 and 0.396, respectively. Survival analysis showed that the 90-day survival rate was significantly lower in the high MLR group than corresponding low MLR group (P=0.011). Logistic multivariate regression analysis showed that after adjusting for other factors, MLR level was an independent prognostic factor in patients with HBV-ACLF. Conclusions: MLR can be used as a potential prognostic indicator for patients with HBV-ACLF, and its clinical value needs to be verified by large-scale prospective randomized trials.

[An investigation and analysis of an acute occupational methyl acetate poisoning]

This article investigated an occupational chemical poisoning incident that occurred in a certain place in Guangdong Province in September 2020, detected the air at the scene, and analyzed the clinical data of the poisoned patients. The peripheral blood methanol concentrations of the three patients were 307.76 mg/L, 354.80 mg/L and 454.14 mg/L when they were admitted to the hospital. The raw and auxiliary materials were analyzed for volatile organic components. Methyl acetate was detected in the finished glue, synthetic resin and compound machine post glue in the glue room, and the relative percentages were 23.05%, 32.79% and 31.68%, respectively. Through comprehensive analysis, it was judged that this incident was an acute occupational methyl acetate poisoning incident, and 3 workers were poisoned.

[Analysis of prognosis-related factors in patients with hepatitis B virus-related acute-on-chronic liver failure]

Objective: To investigate the prognosis-related factors and its predictive value in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF). Methods: Sixty-three cases with HBV-ACLF were enrolled. According to the prognosis of 4-weeks, patients were divided into survival and death group. Univariate and multivariate analyses were performed on the clinical data of the two groups of patients to screen the risk factors affecting prognosis, evaluate its predictive value, and compare them with the MELD score, CTP score, and CLIFACLF score. The data were analyzed using t-test, Mann-Whitney U test, χ (2) test. Multiple logistic regression analysis was used for multiple risk factors. Results: There were 63 cases with HBV-ACLF, with 16 cases (25.40%) in the 4-week survival group, and 47 cases (74.60%) in the death group. The survival group age was 38.38 ± 14.50 years, which was significantly lower than the age of the death group 52.28 ± 12.51 years (P < 0.001). The survival group alpha-fetoprotein (AFP) level was 91.21 (8.38 ~ 154.10)μg/L, which was significantly higher than the level of the death group [12.60 (5.70 ~ 33.80) μg/L, P = 0.039]. The survival group alanine aminotransferase (ALT) level was 925.65 (523.43 ~ 1 364.80) U/L, which was much higher than that of the death group [371.60 (117.30 ~ 895.30) U/L, P = 0.040]. The survival group serum sodium level was (136.59 ± 4.03) mmol /L, which was significantly higher than the level of the death group [(132.22 ± 6.37) mmol/L, P = 0.013]. The survival group ascites severity level was much lower than that of the death group (P = 0.008). The survival group creatinine level was 56.50(49.43 ~ 86.25) μmol/L, which was much lower than the level of the death group [86.20 (68.00 ~ 143.00) μmol/L, P = 0.003]. Multivariate logistic regression analysis showed that ascites (OR = 0.470, 95% CI: 0.226 ~ 0.977) and age (OR = 0.941, 95% CI: 0.888 ~ 0.996) were risk factors affecting the HBV-ACLF prognosis. The area under the curve predicted liver failure prognostic score for ascites and age was 0.821, and the sensitivity and specificity were 68.8% and 87.2%, which was higher than the area under the curve predicted by the MELD score, CTP score, and CLIFACLF score, respectively. Conclusion: Age and ascites can be used to predict the clinical outcome in patients with HBV-ACLF. Younger patients without ascites have a higher survival rate at 4-weeks, but older patients with ascites are more likely to have a lower survival rate.

Metabolomic profile of milk fermented with Streptococcus thermophilus cocultured with Bifidobacterium animalis ssp. lactis, Lactiplantibacillus plantarum, or both during storage

In this study, the microbial interactions among cocultures of Streptococcus thermophilus (St) with potential probiotics of Bifidobacterium animalis ssp. lactis (Ba) and Lactiplantibacillus plantarum (Lp) in fermented milk were investigated during a storage period of 21 d at 4°C, in terms of acidifying activity (pH and titratable acidity), viable counts, and metabolites. A nontargeted metabolomics approach based on ultra-high-performance liquid chromatography coupled with mass spectrometry was employed for mapping the global metabolite profiles of fermented milk. Probiotic strains cocultured with St accelerated milk acidification, and improved the microbial viability compared with the single culture of St. The St-Ba/Lp treatment manifested a higher bacteria viability and acidification ability in comparison with the St-Ba or the St-Lp treatment. Relative quantitation of 179 significant metabolites was identified, including nucleosides, AA, short peptides, organic acids, lipid derivatives, carbohydrates, carbonyl compounds, and compounds related to energy metabolism. The principal component analysis indicated that St treatment and coculture treatments displayed a complete distinction in metabolite profiles, and Lp had a larger effect than Ba on metabolic profiles of fermented milk produced by cofermentation with St during storage. The heat map in combination with hierarchical cluster analysis showed that the abundance of metabolites significantly varied with the starter cultures over the storage, and high abundance of metabolites was observed in either St or coculture samples. The St-Ba/Lp treatment showed relatively high abundance for the vast majority of metabolites. These findings suggest that the profile of the metabolites characterizing fermented milk samples may depend on the starter cultures, and incorporation of probiotics may considerably influence the metabolomic activities of fermented milks.

Analysis of factors leading to lid wiper epitheliopathy

OBJECTIVE

Lid wiper epitheliopathy (LWE) has received more attention during the diagnosis and treatment of the dry eye. However, its causes and pathogenesis remain unclear. We aimed to explore the etiology of LWE by analyzing the association between the severity of LWE and different anatomical and tissue morphological examination characteristics using confocal microscopy on eyes with dry eye syndrome.

PATIENTS AND METHODS

We recruited 350 patients with LWE and dry eye syndrome (350 eyes). We examined the eyes with lid-wiper staining, conjunctival staining, a comprehensive ocular surface exam using the OCULUS keratography 5M, conjunctival impression cytology, and confocal microscopy observations. We analyzed the associations between each indicator and the LWE staining score.

RESULTS

According to the Spearman's analysis, the LWE staining score was weakly associated with thickness of the lipid layer (r=0.1737, p=0.0005) and severity of Meibomian gland dysfunction (r=0.2026, p<0.0001); and strongly associated with staging of conjunctival impression cytology (r= -0.7694, p<0.0001). Pearson's correlation analysis indicated that, LWE staining score was moderately associated with age (r=0.4165, p<0.0001), tear meniscus height (r=0 -0.4019, p<0.0001), and NIKBUT-first (noninvasive keratography tear film breakup time) (r= -0.5108, p<0.0001); and strongly associated with NIKBUT-average (r= -0.7820, p<0.0001) and ocular staining score (r=0.6113, p<0.00001). Some patients presented abnormal blinking. We observed deeper lesion depths and more holes and fissures in the lid wipers of patients with more severe LWE than in patients with milder LWE.

CONCLUSIONS

Abnormal friction factors caused by insufficient lubrication between the lid wiper area and the ocular surface seem to influence the development and/or the severity of LWE. Aggravation of LWE further increases the frictional damage between the lid wiper and the ocular surface.

[Clinical study of transjugular intrahepatic portosystemic shunt with Viatorr stent in 43 cases]

Objective: To investigate the clinical efficacy and safety of transjugular intrahepatic portosystemic shunt (TIPS) with the use of Viator stent in the treatment of cirrhotic portal hypertension. Methods: 43 cases with cirrhotic portal hypertension were implanted with Viatorr stent during TIPS procedure from March 2016 to August 2018. Serological indicators, color Doppler ultrasound, gastroscopy, rebleeding, ascites and hepatic encephalopathy were regularly followed up. Portal venous pressure, liver and kidney function, coagulation indexes were compared by t-test. Stent patency rate, hepatic encephalopathy incidence, rebleeding rate and survival rate were calculated by Kaplan-Meier curve. Results: TIPS procedure success rate was 100% in all patients. Portal pressure gradient was decreased from (25.57 ± 5.50) mmHg to (9.76 ± 2.92) mmHg before and after operation. Alanine aminotransferase (ALT) was significantly higher at 1 month after operation than before operation, but there was no significant difference between 3 and 6 months after and before operation. Total bilirubin, serum ammonia and prothrombin time at 1, 3, and 6 months after operation were higher than before operation. Albumin had no significant change compared with before operation, and creatinine and urea nitrogen were lower than before operation. The cumulative rebleeding rates at 12 and 24 months after operation was 0% and 9%, respectively. Of the 26 patients with ascites, 22 cases (84.6%) had complete disappearance of ascites and 3 (11.5%) had significant decrease of ascites. The cumulative incidence of hepatic encephalopathy at 3, 6, 12 and 24 months after surgery was 11.6%, 17.3%, 21.9% and 21.9%, respectively. The cumulative incidence of stent dysfunction at 12 and 24 months after surgery was 5.6% and 23.7%, respectively. The cumulative survival rate at 12 months and 24 months after surgery was 91.9%. Conclusion: TIPS procedure with Viatorr stent can effectively reduce portal pressure and rebleeding rate, improve intrahepatic shunt patency rate, and will not increase the risk of postoperative hepatic encephalopathy, and has a higher cumulative survival rate.

[Progress in the clinical diagnosis and treatment of hepatic vascular diseases]

The liver has a very special dual blood supply, including the portal vein (65%~75%) and hepatic artery (25%~35%). The hepatic veins returns blood to the systemic circulation via the portal vein, and hepatic artery after hepatic sinusoidal confluence. The lesions on the hepatic vein and its branches can cause ischemia and hypoxia or obstruction of the drainage system, portal hypertension, upper gastrointestinal variceal bleeding, hepatic encephalopathy, and so on. Clinically, hepatic vascular diseases are relatively rare, so the diagnosis and treatment are relatively difficult. Herein, we review the diseases related to the hepatic vascular system.

[Combined effect of noise and hand-transmitted vibration on noise-induced hearing loss in the automobile manufacturing industry]

Objective: To investigate the combined effect of noise and hand-transmitted vibration on noise-induced hearing loss (NIHL) in the automobile manufacturing industry. Methods: From September 2018 to January 2019, cluster sampling was used to select 998 workers in an automobile factory as study subjects, among whom 352 workers exposed to noise alone were enrolled as noise group, 342 workers exposed to noise and hand-transmitted vibration were enrolled as combined effect group, and 304 workers without exposure to occupational hazardous factors were enrolled as control group. A questionnaire survey and pure tone audiometry were performed for all study subjects. An analysis of variance was used for comparison of continuous data between groups, and the chi-square test was used for comparison of categorical data between groups; a ordinal polytomous logistic regression analysis was used to investigate the influencing factors for NIHL (with 0.05 as the inclusion criteria and 0.10 as the exclusion criteria for independent variables) . Results: There was a significant difference in L(Aeq, 8 h) between groups (P<0.05) ; the noise group and the combined effect group had a significantly higher L(Aeq, 8 h) than the control group (P<0.05) , while there was no significant difference in L(Aeq, 8 h) between the noise group and the combined effect group (P>0.05) . The control group had a significantly lower detection rate of hearing loss than the noise group and the combined effect group (P<0.0125) , and the combined effect group had a significantly higher detection rate of hearing loss than the noise group (P<0.0125) . The ordinal polytomous logistic regression analysis showed that after adjustment for confounding factors such as age, working years, sex, smoking, and drinking, both noise exposure and exposure to both noise and hand-transmitted vibration had an influence on workers' hearing (P<0.05) , and the workers exposed to both noise and hand-transmitted vibration had a higher risk of hearing loss than those exposed to noise alone. Conclusion: There may be a combined effect of noise and hand-transmitted vibration in the automobile manufacturing industry, which can increase the risk of NIHL in workers.

[Breakthrough of invasive fungal disease with posaconazole as primary prophylaxis after induction chemotherapy for acute myeloid leukemia]

Objective: To investigate the breakthrough incidence of invasive fungal disease(IFD) and side effects of posaconazole as primary prophylaxis during induction chemotherapy for acute myeloid leukemia(AML). Methods: A total of 206 newly diagnosed AML patients admitted to our department during January 2016 and December 2018 were enrolled in the study. Exclusive criteria were as followings including patients diagnosed as acute promyelocytic leukemia; those who received intravenous antifungal therapy after admission or had history of IFD one month before induction chemotherapy, or those with functional insufficiency of vital organs and those older than 65. Forty-seven patients received posaconazole (posaconazole group), 61 cases received voriconazole (voriconazole group) and 98 cases did not receive any prophylaxis (control group) during induction chemotherapy. Prophylactic efficacy and safety between posaconazole and voriconazole were compared. Results: During induction chemotherapy, five possible cases of IFD occurred in posaconazole group (10.6%); while 11 cases (18.0%) were in voriconazole group including 7 possible, 3 probable and 1 proven. Thirty-five cases (35.7%) in control group were diagnosed as IFD including 19 possible, 11 probable and 5 proven ones. The incidences of IFD in posaconazole and voriconazole group were significantly lower than that in control group (P<0.05). The difference of posaconazole group and voriconazole group was not significant (P>0.05). The reported adverse events in posaconazole group were significantly lower than those in voriconazole group [12.8%(6/47) vs. 32.8%(20/61), P<0.05]. Conclusions: Posaconazole and voriconazole decrease IFD as primary prophylaxis during induction chemotherapy in patients with AML. The prophylactic effect of IFD with posaconazole is similar as voriconazole, but posaconazole shows better safety.

In vitro antioxidant and angiotensin-converting enzyme inhibitory activity of fermented milk with different culture combinations

This study investigated the effects of Lactobacillus plantarum (Lp) and Bifidobacterium animalis ssp. lactis (Ba) in co-cultures with Streptococcus thermophilus (St) on changes in the acidification profile, proteolytic activity, peptide production, in vitro antioxidant activity, and angiotensin-converting enzyme (ACE) inhibitory properties of fermented milks during 21 d of storage at 4°C. The pH values and proteolysis in all batches showed a gradual decrease and increase during storage, respectively. The ACE-inhibitory activity and total antioxidant capacity of all co-fermented milk samples followed a similar pattern, with maximum values on d 6 of storage. The St starter, in conjunction with Ba or Lp or both, enhanced proteolysis, peptide generation, and ACE-inhibitory and antioxidant activity, but decreased pH values compared with St alone. The St-Ba-Lp samples showed higher DPPH^• (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, hydroxyl radical scavenging activity, and total antioxidant capacity, but similar superoxide anion scavenging activity compared to St-Ba or St-Lp samples. The St-Ba samples showed higher DPPH^• radical scavenging activity but lower hydroxyl radical scavenging activity than St-Lp samples. In the ACE-inhibitory assays, the St-Lp samples exhibited relatively low activity among the co-fermented milks, digested or not. The presence of Ba and Lp in fermentation together did not affect ACE-inhibitory activity in undigested fermented milks compared with the presence of Ba alone, and St-Ba-Lp fermented milks demonstrated an increase in ACE-inhibitory activity after simulated gastrointestinal digestion in storage. Pepsin digestion largely improved ACE-inhibitory activity, except in St-Lp samples, in which the activity was reduced. Further hydrolysis by trypsin reduced final activity in digestion. This study suggests that co-cultured fermentation with probiotics improves in vitro antioxidant and ACE inhibition activity in fermented milks, and this effect is partly due to the higher proteolytic activity of probiotics.

[An investigation of an accident of acute mixed gas poisoning]

An accident of mixed acute gas poisoning accident happened in a place in GuangDong in March 2018. To investigates three poisoning workers and related clinical data were summarized., we tested the field air and analyzed the accident reasons. This event due to the staff lack of occupational protection awareness and illegal operation. The working environment must be ventilated before limited space operation, and must be sure that the limited space is safe by toxic gas monitoring. In case of occupational acute gas poisoning, rescuers should help the persons who are poisoned reasonably and meanwhile their own safety.

[Application of semi-quantitative risk assessment method in occupational health risk assessment of wooden furniture manufacturing enterprises]

Objective: To explore the applicability of semi-quantitative risk assessment methods in wood furniture manufacturing companies. Methods: Two medium-sized wooden furniture manufactures were randomly selected as research objects, namely A company and B company. Used the Semi-Quantitative risk assessment method (the ratio method, the index method and the comprehensive method) in the "Guidelines for occupational health risk assessment of chemicals in the workplace" (GBZ/T 298-2017) to conduct occupational hygiene survey, occupational hazard factor testing and occupational health risk assessments for two wood furniture manufacturers from January to October 2018, and compared and analyzed the applicability of these three semi-quantitative risk assessment methods in wooden furniture manufacturing enterprises. Results: The occupational health status of A enterprises was worse than that of B enterprises, and the occupational health risk level was higher than that of B enterprises, and the risk level of A enterprise is 3~4, and the risk level of B enterprise is 2~3. The occupational health risk level obtained by the index method was consistent with the comprehensive method, while the risk level of some occupational disease hazards used the ratio method was inconsistent with the results of the index method and the comprehensive method. Compared with the index method and the comprehensive method, when E/OEL<0.5 or E/OEL≥2, there might be a certain fluctuation in the occupational health risk level obtained by the ratio method. Conclusion: The semi-quantitative risk assessment is more objective, comprehensive and flexible in the application of occupational health risk assessment, and can assess the occupational health risk level of chemical poisons in wood furniture manufacturing enterprises.

[Ikaros family zinc finger 1 mutation is a poor prognostic factor for adult Philadelphia chromosome positive acute lymphoblastic leukemia]

Objective: To analyze the prognostic impact of Ikaros family zinc finger 1(IKZF1) mutation on adult Philadelphia chromosome (Ph1) positive acute lymphoblastic leukemia (ALL) patients. Methods: IKZF1 mutation was detected in 63 adult Ph1 positive ALL patients at diagnosis using capillary electrophoresis. Recruited patients were treated in our center and other three hospitals in Ningbo from January 2014 to January 2017. Clinical data were collected and retrospectively analyzed. Results: Thirty-nine (61.9%) patients were positive IKZF1 mutation in this cohort. The white blood cell (WBC) count in IKZF1 mutation group was significantly higher than that of mutation negative group [(64.6±11.3)×10(9)/L vs. (33.7±5.6)×10(9)/L, P<0.05]. Patients with WBC count over 30×10(9)/L accounted for 56.4% in IKZF1 mutation group. Complete remission (CR) rate in the IKZF1 mutation group was also lower than that of negative group after induction chemotherapy (64.1% vs. 75.0%, P>0.05). IKZF1 was a negative prognostic factor but not independent factor for survival by univariate and multivariate analyses. Patients were divided into chemotherapy and allogeneic transplantation groups. The 3-year overall survival (OS) rate and 3-year leukemia-free survival (LFS) rate in IKZF1 mutation group were significantly lower than those of negative group in both transplantation group (42.3% vs. 59.3%; 31.2% vs. 50.0%; respectively, both P<0.05) and chemotherapy group (24.8% vs. 40.0%; 19.0% vs. 34.3%; respectively, both P<0.05). Conclusion: IKZF1 mutation is a poor prognostic factor for adult Ph1 positive ALL patients.

[Effect of FLT3-ITD with DNMT3A R882 double-mutation on the prognosis of acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation]

目的

探讨FLT3-ITD和DNMT3A R882双突变对急性髓系白血病（AML）患者allo-HSCT预后的影响。

方法

使用直接测序法检测206例接受allo-HSCT的AML患者（M₃和使用分子靶向药物索拉菲尼的病例除外）初诊时骨髓中常见的基因突变组套（包括FLT3-ITD、DNMT3A、c-kit、CEBPA、FLT3-TKD、NPM1），回顾性分析患者的临床资料，比较各基因突变组的移植预后。

结果

①206例AML患者中男104例，女102例，中位年龄38（3~63）岁。FAB分型：M₀ 6例，M₁ 24例，M₂ 56例，M₄ 39例，M₅ 63例，M₆ 6例，不能分类12例。②全部206例患者根据初诊时的突变基因情况分为4组：FLT3-ITD⁺ DNMT3A R882⁺组（A组）19例，FLT3-ITD⁺ DNMT3A R882⁻组（B组）38例，FLT3-ITD⁻DNMT3A R882⁺组（C组）21例，FLT3-ITD⁻DNMT3A R882⁻组（D组）128例。四组间性别、年龄、初诊时白细胞计数、FAB分型、移植前疾病状态、染色体核型、供者类型、预处理方案及GVHD发生率比较，差异无统计学意义（P>0.05）。③A组和B、C、D组比较，2年累积复发率较高[分别为（72.2±2.6）%、（38.6±0.6）%、（36.8±1.6）%、（27.8±0.1）%，P值均<0.05]，总生存率较低[分别为（30.9±13.3）%、（67.5±7.8）%、（61.4±12.4）%、（80.1±3.7）%，P值均<0.05]，无白血病生存率较低[分别为（11.3±10.2）%、（47.9±8.4）%、（56.8±12.5）%、（79.7±3.6）%，P值均<0.05]。

结论

伴有FLT3-ITD与DNMT3A R882双突变的AML患者移植后累积复发率较高，总生存率和无白血病生存率较差。

[Study on determination of ethylal in workplace air by gas chromatography]

Objective: A solvent desorption-gas chromatography method for determination of ethylal in workplace air has been established. Methods: Ethylal in workplace air was collected by activated carbon tube and desorbed with carbon disulfide, and the desorption solutions were analysed by capillary column GC with FID detector. Results: The method presented a good linearity in the range of 0.87~34 800.00 mg/L of ethylal in the standard solution, with the correlation coefficient being r=0.999 7. The limit of detection and the limit of quantification of this method were respectively 0.20 mg/L and 0.80 mg/L, and the minimum detectable concentration and the minimum quantification concentration of this method were respectively 0.17 mg/m(3) and 0.60 mg/m(3) per 1.50 L of air.The within-run precision of the method was 2.93%-6.20%, and the between-run precision 3.67%-6.44%. The desorption efficiency between 94.22%-97.27%. Ethylal in activated carbon tube could be kept at least 7 days at room temperature without significant loss. Conclusion: The method could be used for determination of ethylal in workplace air.

Propofol inhibits carbachol-induced chloride secretion by directly targeting the basolateral K+ channel in rat ileum epithelium

BACKGROUND

Propofol is a widely used intravenous general anesthetic. Acetylcholine (ACh) is critical in controlling epithelial ion transport. This study was to investigate the effects of propofol on ACh-evoked secretion in rat ileum epithelium.

METHODS

The Ussing chamber technique was used to investigate the effects of propofol on carbachol (CCh)-evoked short-circuit currents (Isc).

KEY RESULTS

Propofol (10^-2 -10^-6  mol/L) attenuated CCh-evoked Isc of rat ileum mucosa in a dose-dependent manner. The inhibitory effect of propofol was only evident after application to the serosal side. Pretreatment with tetrodotoxin (TTX, 0.3 μmol/L, n=5) had no effect on propofol-induced inhibitory effect, whereas serosal application of K⁺ channel inhibitor, glibenclamide, but not, an ATP-sensitive K⁺ channel inhibitor, largely reduced the inhibitory effect of propofol. In addition, pretreatment with either hexamethonium bromide (HB, nicotinic nACh receptor antagonist) or Cl^- channel blockers niflumic acid and cystic fibrosis transmembrane conductance regulator (inh)-172 did not produce any effect on the propofol-induced inhibitory effect.

CONCLUSIONS & INFERENCES

Propofol inhibits CCh-induced intestinal secretion by directly targeting basolateral K⁺ channels.

Genetic variability of Myzus persicae nicotianae densovirus based on partial NS and VP gene sequences

We previously described a novel densovirus [Myzus persicae nicotianae densovirus (MpnDV)] infecting M. persicae nicotianae (Hemiptera: Aphididae) with 34% prevalence. This single-stranded DNA virus has a 5480-nucleotide ambisense genome and belongs to the Densovirinae subfamily within the family Parvoviridae. In the present study, we estimated the genetic diversity of MpnDV using partial nonstructural protein (NS) and capsid protein (VP) gene sequences from 10 locations in China. First, we identified MpnDV-positive samples by amplifying a 445-bp fragment with primers MpDVF/MpDVR. Subsequently, we amplified and sequenced COI genes with primers MpCOIF/ MpCOIR, and partial NS and VP sequences with primers MpnDVF1/MpnDVR1. The respective 655-, 1461-, and 423-bp COI, NS, and VP fragments were used to analyze the genetic diversity of MpnDV using MEGA 6.0 and DnaSP 5.0. The high level of identity shared by all COI sequences (>99%) suggested that the aphids sampled were of the same species, and indicated population homogeneity across the 10 locations investigated. The nucleotide diversity of MpnDV sequences (0.0020 ± 0.0025) was significantly higher than that of the COI genes (0.0002 ± 0.0005). The pairwise fixation index for MpnDV was 0.832, and the total gene flow was 0.05. Phylogenetic analysis revealed that the MpnDV haplotypes clustered according to geographical location, except for those from the Liaoning and Shanxi provinces. In conclusion, MpnDV demonstrated a low level of gene flow and high genetic diversity, suggesting that it is vertically transmitted, and implying that endosymbiotic viruses could be used as markers in studies of insect population genetics.

[An investigation of ionizing radiation dose in a manufacturing enterprise of ion-absorbing type rare earth ore]

Objective: To investigate radioactive source term dose monitoring and estimation results in a manufacturing enterprise of ion-absorbing type rare earth ore and the possible ionizing radiation dose received by its workers. Methods: Ionizing radiation monitoring data of the posts in the control area and supervised area of workplace were collected, and the annual average effective dose directly estimated or estimated using formulas was evaluated and analyzed. Results: In the control area and supervised area of the workplace for this rare earth ore, α surface contamination activity had a maximum value of 0.35 Bq/cm² and a minimum value of 0.01 Bq/cm²; β radioactive surface contamination activity had a maximum value of 18.8 Bq/cm² and a minimum value of 0.22 Bq/cm². In 14 monitoring points in the workplace, the maximum value of the annual average effective dose of occupational exposure was 1.641 mSv/a, which did not exceed the authorized limit for workers (5 mSv/a) , but exceeded the authorized limit for general personnel (0.25 mSv/a) . The radionuclide specific activity of ionic mixed rare earth oxides was determined to be 0.9. Conclusion: The annual average effective dose of occupational exposure in this enterprise does not exceed the authorized limit for workers, but it exceeds the authorized limit for general personnel. We should pay attention to the focus of the radiation process, especially for public works radiation.

Population genetic structure of Myzus persicae nicotianae (Hemiptera: Aphididae) in China by microsatellite analysis

The tobacco aphid, Myzus persicae nicotianae (Hemiptera: Aphididae), is an important agricultural pest that feeds on host plants and transmits plant viruses in China. To effectively control this pest, we investigated the genetic variation and genetic structure of 54 populations of tobacco aphids collected in China, using five microsatellite loci. An average of 7 alleles with effective number ranging from 1.5 to 6.6 was detected using these five loci, and the average polymorphic information content (PIC) was 0.652, suggesting that the five selected microsatellite loci were polymorphic and suitable for the study of population genetics. The expected heterozygosities in the populations studied ranged from 0.128 and 0.653, with an average value of 0.464. However, the observed heterozygosities ranged from 0.250 and 0.942 (average = 0.735), revealing a high genetic variability and heterozygosity excess in the Chinese tobacco aphid populations. The global fixation index (F(ST)) and mean gene flow (N(m)) were 0.34 (P < 0.0001) and 0.50, respectively, suggesting the high genetic differentiation among Chinese populations. The 54 populations of tobacco aphids were classified into two groups. The populations did not cluster geographically, as populations from the same provinces were usually present in different clusters. This was also confirmed by the Mantel test, which showed no significant correlation between the genetic distance and geographical distance or altitude. Long distance migration might be responsible for the lack of distance-related isolation.

Cancer therapy improvement with mesoporous silica nanoparticles combining photodynamic and photothermal therapy

In this work, we develop novel mesoporous silica composite nanoparticles (hm-SiO2(AlC4Pc)@Pd) for the co-delivery of photosensitizer (PS) tetra-substituted carboxyl aluminum phthalocyanine (AlC4Pc) and small Pd nanosheets as a potential dual carrier system to combine photodynamic therapy (PDT) with photothermal therapy (PTT). In the nanocomposite, PS AlC4Pc was covalently conjugated to a mesoporous silica network, and small Pd nanosheets were coated onto the surface of mesoporous silica by both coordination and electrostatic interaction. Since small Pd nanosheets and AlC4Pc display matched maximum absorptions in the 600-800 nm near-infrared (NIR) region, the fabricated hm-SiO2(AlC4Pc)@Pd nanocomposites can generate both singlet oxygen and heat upon 660 nm single continuous wavelength (CW) laser irradiation. In vitro results indicated that the cell-killing efficacy by simultaneous PDT/PTT treatment using hm-SiO2(AlC4Pc)@Pd was higher than PDT or PTT treatment alone after exposure to a 660 nm CW-NIR laser.

Ultrafast insulator–metal phase transition in vanadium dioxide studied using optical pump–terahertz probe spectroscopy

We studied the ultrafast dynamic behavior of the photoinduced insulator–metal phase transition in VO2 thin film using optical pump–terahertz probe spectroscopy with different excitation fluences and at different temperatures. We observed two processes in the insulator–metal phase transition in VO2: a fast process and a slow process. The fast process is a nonthermal process, which is ascribed to the nucleation of the metal phase, while the slow process is strongly affected by temperature and is ascribed to the thermally driven growth and coalescence of metal domains in VO2. The transient complex conductivity spectra at different delay times are also investigated.

Isolation and characterization of the anthocyanidin genes PAL, F3H and DFR of Scutellaria viscidula (Lamiaceae)

Anthocyanidin is a group of flavonoid compounds used as a vegetable pigment and plays an important role in flower coloration and environmental adaptations of the Chinese ornamental plant Scutellaria viscidula. We determined the cDNA sequences of phenylalanine ammonia-lyase (SvPAL), flavanone 3-hydroxylase (SvF3H) and dihydroflavonol 4-reductase (SvDFR) genes in S. viscidula. Comparative analysis showed that the protein products of these three genes did not have a transit peptide at their N-terminal portion, which indicated that these enzymes were directly involved in the substrate conversion in the cytoplasmic matrix. Bioinformatic analysis further revealed that Svpal, Svf3h and Svdfr were the members of flavonoid biosynthetic genes with highly conserved motifs. Based on phylogenetic tree analysis, it appears that PAL, F3H or DFR from different plants might have originated from the same ancestor. This study can help to map and regulate the important stages involved in anthocyanidin biosynthesis by genetic engineering to diversify flower color and improve the ornamental value of S. viscidula.

Characterization of domain structure of periodically poled Mg:LiNbO3 through multifrequency terahertz generation

Terahertz (THz) wave generation in a periodically poled Mg:LiNbO3 crystal was detected by a pump-probe technique and analyzed using frequency and time-frequency spectra. Multifrequency THz waves were clearly observed, providing information about the domain structure of the crystal. A theoretical T-function model was used to fit the frequency spectrum. A method that can characterize the detailed domain structure and THz capabilities of the inner crystal's parts is proposed.

Ultrafast and Large Third-Order Nonlinear Optical Properties of CdS Nanocrystals in Polymeric Film

We report the ultrafast and large third-order nonlinear optical properties of CdS nanocrystals (NCs) embedded in a polymeric film. The CdS NCs of 2 nm radius are synthesized by an ion-exchange method and highly concentrated in the two layers near the surfaces of the polymeric film. The two-photon absorption coefficient and the optical Kerr coefficient are measured with laser pulses of 250 fs duration at 800 nm wavelength. The one-photon and two-photon figures of merit are determined to be 3.1 and 1.3, respectively, at irradiance of 2 GW/cm(2). The observed nonlinearities have a recovery time of approximately 1 ps. The two-photon-generated free carrier effects have also been observed and discussed. These results demonstrate that CdS NCs embedded in polymeric film are a promising candidate for optical switching applications.

Implication of maternal-cell contamination in the clinical banking of umbilical cord blood

BACKGROUND

The increasing utilization of human UC blood (UCB) in transplantation has drawn attention to the need for rationalization of selection, collection, processing, testing, banking and release of UCB. However, the issue of maternal blood contamination has not been well addressed. There are concerns that maternal T cells might elicit GvHD post-UCB transplant.

METHODS

Maternal T cells in 58 male UCB allografts were enumerated using fluorescent in situ hybridization and flow cytometry. Obstetric factors, preceding labor, multi-parity and gestational age, were also analyzed.

RESULTS

Levels of maternal cells of 0.75-5.25% were found in 15.5% (9/58) UCB. There was no association of maternal-cell contamination with preceding labor [25% (2/8) with previous delivery versus 35.4% (17/48) first born, P = 0.702], nor any correlation with multi-parity [37.5% (3/8) para > or = 3 versus 16.7% (8/48) para < 3, P = 0.181]. Gestation age of newborns also exhibited no association with maternal-cell contamination (39.47 weeks in newborn UCB with maternal cells, versus 39.58 weeks without: P = 0.674). The extrapolated maternal T cells/kg in nine UCB transplants were 1.05 x 10(5) +/- 1.12 x 10(5) (3.40 x 10(4) - 3.18 x 10(5)).

DISCUSSION

In relation to the arbitrary threshold of 1 x 10(5) T cells/kg in HLA-mismatched transplants utilizing T-cell depleted BM, 22.2% (2/9) of UCB transplants having maternal-cell contamination might be at risk of GvHD. Data support the need for testing for maternal blood in UCB, and evaluating the clinical relevance of GvHD in patients post-UCB transplant. The establishment of guidelines and standards for release of such UCB collections would be advisable in evidence-based UCB transplantation.

Low frequency of p53 gene mutations in breast cancers of Japanese-American women

Differences in frequencies and patterns of somatic p53 gene mutations among racially and geographically diverse populations presumably reflect exposure to different mutagens or different responses to certain mutagens. On emigration to the United States, Japanese women experience, over several generations, a four- to fivefold increase in the incidence of breast cancer. To determine whether this increased incidence is associated with a change in the frequency and/or type of p53 mutation in their tumors, we examined paraffin-embedded samples of primary breast cancers from Japanese-American women in Los Angeles County, CA. Mutations in exons 5-9 and adjacent intronic regions of the p53 gene were identified and confirmed by direct sequencing. Seven mutations, including 5 missense, were detected in 44 primary breast carcinomas, a frequency of 16%. There were six transitions and one transversion. As expected, overexpression of p53 protein, detected by immunohistochemistry, occurred in tumors with missense mutations; tumors with nonsense or splice junction mutations had no detectable p53 protein. The frequency of p53 gene mutations showed no increase over that previously found in breast cancers of native Japanese women. The increased incidence of breast cancer in Japanese-American women is likely to be multifactorial in nature and warrants further studies.

The health status of rural and urban ambulatory elderly in Taipei County

BACKGROUND

To study the differences in the health status of rural and urban ambulatory elderly in Taipei County.

METHOD

Non-compulsory general health check-up for elderly people over 65 years old in rural and urban areas. The content of the health examination included past medical history, health behavior, physical examination, laboratory examination, electrocardiogram and x-ray. Chi square test, t-test and logistic regression were applied for analysis. Risk factors relating to the cardiovascular system were included in the study. Gender differences affecting the prevalence of diseases and health behavior were also considered in the analysis.

RESULTS

Significantly higher proportions of the rural elderly men smoked, drank alcohol, and had hypertension and impaired renal function. On the other hand, higher proportions of rural elderly women were obese and had diabetes, hypertension and renal impairment. The mean plasma glucose level of newly-diagnosed diabetic patients in the rural area was significantly higher than that in the urban area (p < 0.05). Diabetes, obesity, hypercholesterolemia and smoking were significantly associated with hypertension. The odds ratio for hypertension between rural and urban areas was 1.45 (p < 0.0001). The cardiovascular risk-rating score of rural elderly was statistically higher than that of urban elderly (p < 0.001).

CONCLUSION

There were some minor differences in health status between urban and rural elderly. Health promotion should be varied according to the needs of various communities and various risk groups. Further studies should concentrate on prospective cohort research with well-defined determinants to evaluate whether cost-effective biopsychosocial intervention is necessary.

Maternal-specific footprints at putative CTCF sites in the H19 imprinting control region give evidence for insulator function

Parent-of-origin-specific expression of the mouse insulin-like growth factor 2 (Igf2) gene and the closely linked H19 gene are regulated by an intervening 2 kb imprinting control region (ICR), which displays parentspecific differential DNA methylation [1] [2]. Four 21 bp repeats are embedded within the ICR and are conserved in the putative ICR of human and rat Igf2 and H19, suggesting that the repeats have a function [3] [4]. Here, we report that prominent DNA footprints were found in vivo on the unmethylated maternal ICR at all four 21 bp repeats, demonstrating the presence of protein binding. The methylated paternal ICR displayed no footprints. Significantly, the maternal-specific footprints were localized to putative binding sites for CTCF, a highly conserved zinc-finger DNA-binding protein with multiple roles in gene regulation including that of chromatin insulator function [5] [6]. These results strongly suggest that the maternal ICR functions as an insulator element in regulating mutually exclusive expression of Igf2 and H19 in cis.

Highly sensitive mutation screening by REF with low concentrations of urea: A blinded analysis of a 2-kb region of the p53 gene reveals two common haplotypes

Restriction endonuclease fingerprinting (REF), a hybrid modification of single-strand conformation polymorphism (SSCP) and restriction endonuclease digestion, has been used previously to detect mutations in 1- to 2-kb segments of DNA. This paper demonstrates that fragment resolution, and thus sensitivity of REF, can be markedly improved by electrophoresis under partially denaturing, rather than nondenaturing, conditions, for genes with a high G+C content. A 2. 1-kb segment of the p53 tumor suppressor gene (54.5% G+C) containing exons 5-9, including the intervening introns, was screened in a blinded analysis of 48 samples from human breast tumors containing known wild-type or mutant p53 genes. In gels containing 0.5 M urea, 97% of the mutant samples were detected correctly, and more than 80% of the mutations were localized within a 200-bp region. In the process of this methodological analysis, it was discovered that: (1) there are two common and four uncommon haplotypes; (2) the two common haplotypes occurred in the three races examined, suggesting an ancient origin; and (3) haplotype II is of substantially higher frequency in the Chinese relative to Japanese (P = 0.023) and Caucasians (P = 0.005). Two other improvements in the REF procedure included (1) the selection of an optimal set of restriction endonucleases by new software (REF Select) developed recently in our laboratory; and (2) the addition of an oligonucleotide "tail," containing two recognition sequences for restriction endonucleases, to the PCR primers to prevent coterminal fragments at the end of amplified products. These modifications facilitate the use of REF for efficient and sensitive mutation screening in p53 and other genes with a high G+C content.

Atypical protein kinase C isozyme zeta mediates carbachol-stimulated insulin secretion in RINm5F cells

Carbachol-stimulated insulin release in the RINm5F cell is associated with elevation of the cytosolic Ca2+ concentration ([Ca2+]i) through mobilization of Ca2+ from thapsigargin-sensitive intracellular stores and with the generation of diacylglycerol (DAG). Thus carbachol activates phospholipase C, and this was thought to be the means by which it stimulates insulin secretion. However, when the elevation of [Ca2+]i was blocked by thapsigargin, the effect of carbachol to stimulate insulin release was unchanged. Thus the effect of carbachol to increase [Ca2+]i was dissociated from the stimulation of release. When the role of protein kinase C (PKC) was examined, carbachol-stimulated insulin release was found to be unaffected by phorbol ester-induced downregulation of PKC, using 12-O-tetradecanoylphorbol-13-acetate (TPA), and by the PKC inhibitors staurosporine, bisindolylmaleimide, and 1-O-hexadecyl-2-O-methylglycerol (AMG-C16). These treatments abolished the stimulation of release by TPA. Thus the carbachol activation of PKC appeared also to be dissociated from the stimulation of insulin release. However, when the activation of several different PKC isozymes was studied, an atypical PKC isozyme, zeta, was found to be translocated by carbachol. By Western blotting analysis, carbachol selectively translocated the conventional PKC isozymes alpha and beta (the activation of which is dependent on Ca2+ and DAG) from the cytosol to the membrane. Carbachol also translocated the atypical PKC isozyme zeta, which is insensitive to Ca2+, DAG, and phorbol esters. The PKC inhibitors staurosporine, bisindolylmaleimide, and AMG-C16 blocked the stimulated translocation of PKC-alpha and -beta, but not that of PKC-zeta. Prolonged treatment of the cells with TPA downregulated PKC-alpha and -beta, but not PKC-zeta. Under all these conditions, carbachol-stimulated insulin release was unaffected. However, a pseudosubstrate peptide inhibitor specific for PKC-zeta inhibited the translocation of PKC-zeta and 70% of the carbachol-stimulated insulin secretion. The data indicate that carbachol-stimulated insulin release in RINm5F cells is mediated to a large degree by the activation of the atypical PKC isozyme zeta.

A cell perifusion system of isolated rat islets for studies on rapid insulin-glucose dynamics

We have developed a cell perifusion system of isolated rat islets, to improve the accuracy of controlling the medium content and the stability of the medium flow. This new system presents the following characteristics: (1) There is always a consistent flow in the perifusion chamber and only half of its volume is altered when switching the medium. (2) The medium containing test substances can be prepared and held ready in very close proximity to islets. The test glucose media are introduced to the islets immediately after a switch. (3) The environment of the islets could be repeatedly changed from one state to another in a rigorous stepwise manner. The system can provide an accurate switch of glucose concentrations both in time and quantity without introducing pressure disturbances, which makes a suitable tool for studies on rapid insulin-glucose dynamics. In experiments of perifused rat islets, our results further confirmed the observation that the amplitudes of oscillatory insulin secretions were magnified when glucose levels increased but their periods were unaffected. In addition, insulin secretions instantly increased in response to the sudden increase of glucose levels, but gradually decreased in response to the sudden decrease of glucose levels.

Identification of muscarinic receptor subtypes in RINm5F cells by means of polymerase chain reaction, subcloning, and DNA sequencing

Carbachol can stimulate insulin release in RINm5F cells by a mechanism that does not involve the elevation of cytosolic free Ca2+ concentrations or the activation of conventional protein kinase Cs (Mol Pharmacol 47:863-870, 1995). Thus, a novel signal transduction pathway links the muscarinic activation of the cells to increased insulin secretion. The question arises as to whether the pathway results from a novel receptor, different from the five established muscarinic receptors, or whether a "normal" receptor in the RINm5F cell activates a novel pathway. To distinguish between these two possibilities, the muscarinic receptors in the RINm5F cell were identified. Using polymerase chain reaction, combined with subcloning and DNA sequencing techniques, the cDNAs that encode the established M3 and M4 receptors were identified. The cDNAs for the Ml, M2, and M5 receptors were not found. Pharmacological studies showed a rank order of potency for muscarinic receptor subtype antagonists to inhibit carbachol-induced insulin release (half-maximal inhibitory concentration [pIC50] values given in parentheses): atropine (nonselective, 9.0) > 4-diphenyl-acetoxy-N-methyl piperidine methiodide (M3/M1, 8.6) > para-fluoro-hexahydrosiladiphenidol (M3, 8.1) > hexahydrosiladiphenidol (M3, 8.0) > tropicamide (M4, 6.4) > pirenzepine (M1, 6.1) > methoctramine (M2, 5.9). This antagonist profile suggests that it is the M3 receptor that mediates carbachol-induced insulin release. In this case, the novel signaling involved in the unusual carbachol response would not be due to a novel receptor but to the well-characterized M3 receptor. It appears, therefore, that the novel portion of the signaling pathway lies downstream of the M3 receptor and may consist of products of phosphatidylinositol hydrolysis, other than inositol triphosphate and diacylglycerol, resulting from the activation of phospholipase C. While a contributory role of the M4 receptor cannot be ruled out, there is no evidence in its favor other than its presence in the cell.

Reexpression of thyroid peroxidase in a derivative of an undifferentiated thyroid carcinoma cell line by introduction of wild-type p53

Loss of function of p53 is believed to result in transformation through impairment of its properties as a transcription factor, which interferes with the regulation of the cell cycle and under certain conditions, with programmed cell death. We report that stable transfection of clonal undifferentiated thyroid carcinoma cell lines harboring endogenous p53 mutations with a wild-type p53 expression vector only rarely yields transfectants expressing authentic wild-type p53. Among these, most exhibited an increase in doubling time and an impairment of colony formation in soft agar. Only one clonal wild-type p53-overexpressing derivative of the NPA papillary carcinoma cell line was obtained, and these cells were found to reexpress thyroid peroxidase (TPO). This clone also demonstrated reexpression of the paired box domain transcription factor Pax-8, which specifically activates transcription of TPO. Wild-type p53 did not directly stimulate transcriptional activity of a TPO promoter construct. Although the low frequency of authentic wild-type p53 stable transfectants limits the power of this analysis, these data suggest that in addition to its role in malignant transformation, p53 may be significant in the determination or maintenance of cell differentiation in thyroid neoplasms.

Unusual carbachol responses in RINm5F cells: evidence for a "distal" site of action in stimulus-secretion coupling

The mechanisms by which carbachol stimulates insulin release were studied in RINm5F cells. Stimulation was associated with mobilization of Ca2+ from thapsigargin-sensitive intracellular stores and elevation of the cytosolic Ca2+ concentration ([Ca2+]i). However, when the elevation of [Ca2+]i was blocked by prior treatment of the cells with thapsigargin or with the anticalmodulin agents W-7 or W-13, the effect of carbachol to stimulate insulin release was unchanged. Thus, the effect of carbachol to increase [Ca2+]i was dissociated from the stimulation of release. The role of protein kinase C (PKC) was next investigated. Carbachol-stimulated insulin release was unchanged by phorbol ester-induced down-regulation of PKC, at a time when the stimulation of release by 12-O-tetradecanoylphorbol-13-acetate was abolished. Similarly, when the effect of 12-O-tetradecanoylphorbol-13-acetate to stimulate release was blocked by each of three separate PKC inhibitors (staurosporine, bisindolylmaleimide, or 1-O-hexadecyl-2-O-methylglycerol), carbachol stimulated insulin release normally. Thus, the carbachol activation of PKC was also dissociated from the stimulation of insulin release. Finally, the effect of carbachol was examined in PKC-down-regulated cells in the simultaneous presence of thapsigargin. Carbachol still stimulated insulin release normally. It is concluded that carbachol stimulates insulin release in RINm5F cells by a novel mechanism that does not involve the elevation of [Ca2+]i or the activation of PKC. The action of carbachol appears to be exerted at a "distal site," beyond the point of increased [Ca2+]i, in stimulus-secretion coupling.

Effects of galanin on short circuit current and electrolyte transport in rabbit ileum

Galanin decreased short circuit current (Isc) and increased active Na+ and Cl- absorption in rabbit ileum. In the absence of calcium, the galanin-induced decrease in Isc was inhibited by approximately 60%. Tetrodotoxin significantly reduced the effect of galanin on Isc, and tetrodotoxin and EGTA totally blocked the effect, indicating that the nonneuronal mediator of the effect is Ca2+ dependent. Galanin binding to basolateral membranes prepared from ileal epithelial cells was specific and of high affinity. These results suggest the involvement of this peptide in the regulation of intestinal epithelial cell function.

Aberrant deoxyribonucleic acid methylation in human thyroid tumors

DNA methylation is a covalent modification of cytosine residues that occurs at the dinucleotide sequence CpG in vertebrates. Abnormal patterns of DNA methylation are observed consistently in human tumors, including widespread areas of genomic hypomethylation as well as regional sites of hypermethylation. We examined the DNA of benign and malignant human thyroid tumors for changes in the methylation state of the genes for human GH, platelet-derived growth factor B-chain, and H-ras. The human GH gene was aberrantly methylated in 6 of 22 (27%) nodules from multinodular goiters (MNG), 21 of 33 (64%) follicular adenomas (FA), and 10 of 16 (63%) papillary carcinomas (PC). Platelet-derived growth factor B-chain was also abnormally methylated in 4 of 13 (31%) MNG, 17 of 24 (71%) FA, and 9 of 13 (69%) PC. The H-ras gene, located within a region on chromosome 11p known to be a hot spot for hypermethylation in other tumors types, showed complex patterns of methylation (mainly hypermethylation) in 6 of 22 (27%) MNG, 22 of 35 (63%) FA, and 10 of 16 (63%) PC. Those tumors with methylation abnormalities tended to be affected at multiple loci (i.e. aberrant patterns with all 3 probes), whereas those that were negative were usually normal at all sites. Benign and malignant thyroid neoplasms show a high prevalence of aberrant methylation patterns of selected genes. Adenomatous nodules from multinodular goiters, consisting largely of hyperplastic tissue, have a lower frequency of these events. Aberrant DNA methylation may contribute to subsequent cell transformation through changes in DNA conformation, transcriptional activity, and/or increased fragile site instability. This suggests that widespread changes in DNA methylation may occur as a relatively early step in thyroid tumor formation.

Growth factor production by human thyroid carcinoma cells: abundant expression of a platelet-derived growth factor-B-like protein by a human papillary carcinoma cell line

As papillary thyroid carcinoma cells grow surrounding finger-like structures of stromal tissue, we postulated they may secrete a growth factor(s) for mesenchymal cells and that these would be distinct from any mitogenic factors elaborated by follicular carcinomas. Conditioned medium from both the human papillary carcinoma cell line NPA and the follicular carcinoma cell line WRO evoked a 20- to 30-fold increase in [3H]thymidine incorporation into NIH3T3 cell DNA. NPA cell growth factor activity largely eluted with 0.5 mol/L NaCl from a heparin-Sepharose column. NPA-conditioned medium competed in a platelet-derived growth factor-B (PDGF-B) RRA, and the mitogenic activity was partially blocked by an anti-PDGF-BB antibody. An immunoprecipitated PDGF-B-like protein from NPA cells was about 17 kilodaltons in a reducing gel, but, in contrast to wild-type PDGF-BB, did not change its electrophoretic mobility in an unreduced sodium dodecyl sulfate-polyacrylamide gel electrophoresis. NPA cells expressed an abundant 1.4-kilobase RNA that hybridized to probes for the 5'-untranslated and amino-terminal domains of PDGF-B and was distinct from the 4.2-kilobase wild-type PDGF-B chain transcript. There were no structural changes in the PDGF-B gene, as determined by cytogenetic analysis and restriction mapping. However, the PDGF-B gene in the NPA cells was hypomethylated compared to that in normal thyroid tissue or WRO cells. In contrast, the mitogenic activity of WRO cells bound to heparin with high affinity and was blocked by a basic fibroblast growth factor (bFGF) antibody. WRO cells contained abundant bFGF mRNA. Both cell lines abundantly expressed transforming growth factor-beta mRNA. Thus, NPA and WRO cells express powerful, yet distinct, mesenchymal cell growth factors. Whereas WRO cells express abundant bFGF, NPA cells produce a novel PDGF-B-like protein, which may correspond to a mutated form of PDGF-B-chain.

High prevalence of mutations of the p53 gene in poorly differentiated human thyroid carcinomas

The development and progression of thyroid tumors is signaled by phenotype-specific mutations of genes involved in growth control. Molecular events associated with undifferentiated thyroid cancer are not known. We examined normal, benign, and malignant thyroid tissue for structural abnormalities of the p53 tumor suppressor gene. Mutations were detected by single-strand conformation polymorphisms of PCR-amplified DNA, using primers bracketing the known hot spots on either exons 5, 6, 7, or 8. The prevalence of mutations was as follows: normal thyroid 0/6; follicular adenomas 0/31; papillary carcinomas 0/37; medullary carcinomas 0/2; follicular carcinomas 1/11; anaplastic carcinomas 5/6; thyroid carcinoma cell lines 3/4. Positive cases were confirmed by direct sequencing of the PCR products. All five anaplastic carcinoma tissues and the anaplastic carcinoma cell line ARO had G:C to A:T transitions leading to an Arg to His substitution at codon 273. In both tumors and cell lines, examples of heterozygous and homozygous p53 mutations were identified. The only thyroid carcinoma cell line in which p53 mutations were not detected in exons 5-8 had markedly decreased p53 mRNA levels, suggesting the presence of a structural abnormality of either p53 itself or of some factor controlling its expression. The presence of p53 mutations almost exclusively in poorly differentiated thyroid tumors and thyroid cancer cell lines suggests that inactivation of p53 may confer these neoplasms with aggressive properties, and further loss of differentiated function.

Allelotype of human thyroid tumors: loss of chromosome 11q13 sequences in follicular neoplasms

Two classes of genes are the targets of mutations involved in human tumorigenesis: oncogenes, the activation of which leads to growth stimulation, and tumor suppressor genes, which become tumorigenic through loss of function, often through allelic deletion. To obtain evidence for a role for tumor suppressor genes in thyroid tumorigenesis, we examined DNA from 80 thyroid neoplasms for loss of heterozygosity in multiple chromosomal loci using 19 polymorphic genomic probes. None of the informative thyroid tumors studied had allelic loss detected with probes for chromosome 2q (D2S44), 3p (D3F15S2, D3S32), 3q (D3S46), 4p (D4S125), 6p (D6S40), 8q (D8S39), 9q (D9S7), 12p (D12S14), 13q (D13S52), 17p (D17S30), or 18q (D18S10). One of eight of the follicular adenomas had a 10q deletion detected with marker D10S15, and one of 26 had a 10q deletion detected with D10S25. One of two of the follicular carcinomas had an 11p deletion in the H-ras locus. The most significant findings were on chromosome 11q13, the site containing the putative gene predisposing to multiple endocrine neoplasia type I. Four of 27 follicular adenomas had loss of heterozygosity for probes in this region. Allelic deletions were detected with the following probes: D11S149, PYGM, D11S146, and INT2. None of 13 informative papillary carcinomas and none of two follicular carcinomas had loss of heterozygosity detectable with these 11q13 markers. Allelic loss is a relatively infrequent event in human thyroid tumors. Deletions of chromosome 11q13 are present in about 14% of follicular, but not papillary, neoplasms.(ABSTRACT TRUNCATED AT 250 WORDS)

Edge extraction by active defocusing

A novel edge extraction method that employs an active defocusing technique is presented. The method is based on the principle that a Laplacian-of-Gaussian (LOG) operation can be approximated by a Difference-of-Gaussian (DOG) operation. While such an operation is usually done in digital image processing, it can also be very effective conducted in a combination of optical techniques and digital processing. In this edge extraction method, a focused image of an object in a scene is first acquired. The image of the scene is then slightly defocused by changing the focal length of the camera. A real time subtraction operation is applied to subtract the defocused image from the previously acquired image. It produces a residual image that emphasizes abrupt intensity variations. An objective evaluation, called an edge index, is performed on the resulting image. The amount of defocusing is carefully adjusted according to this measurement so that a desired edge image is generated. Boundaries of objects can then be obtained by further enhancement of the edge image. Since this edge detection method is an optical-based process aided by digital processing, it is fast and relatively inexpensive.