Severe Thrombocytopenia with Acute Cerebral Infarction: A Case Report and Literature Review

Common causes of thrombocytopenia include pseudo-thrombocytopenia, splenomegaly, decreased bone marrow production, and increased platelet destruction or depletion. The main clinical manifestation is bleeding, and thrombosis-related complications are rare. This article reports an 87-year-old woman with severe thrombocytopenia for more than 7 years. On day 6 in the hospital, the patient suddenly fell into a coma, and emergency head computed tomography (CT) displayed acute cerebral infarction of the left cerebellar hemisphere, brainstem, and left thalamus. Although thrombocytopenia is often associated with bleeding, there is still a need for vigilance against ischemic diseases. We analyzed the possible causes of acute cerebral infarction with thrombocytopenia and reviewed the literature. Our case is different from the causes of cerebral infarction reported in previous articles, so the relationship between thrombocytopenia and acute cerebral infarction needs further study. The patient, in this case, was not given anticoagulant or antiplatelet therapy but recovered well. It shows that individualized treatment is effective.

Comparative analysis of surgical and oncologic outcomes of robotic, laparoscopic and open radical nephrectomy with venous thrombectomy: a propensity-matched cohort study

OBJECTIVE

To provide insight into the surgical and oncological outcomes of robotic, laparoscopic and open radical nephrectomy with venous thrombectomy (RALRN-VT, LRN-VT, ORN-VT) in patients with renal tumor and venous thrombus.

MATERIALS AND METHODS

A propensity-matched retrospective cohort study containing 324 patients with renal tumor and venous thrombus from January 2014 to August 2021 was analyzed. We compared surgical outcomes and we used the Kalan-Meier method to assess the overall survival (OS), tumor-specific survival (TSS), metastasis-free survival (MFS) and local recurrence-free survival (LRFS). The Pearson chi-square test and Fisher exact test, Wilcoxon rank sum test, Cox proportional hazards regression model and log-rank test were used.

RESULTS

After matching, baseline characteristics were comparable in the RALRN-VT, LRN-VT and ORN-VT group. The RALRN-VT group had the least operative time (median 134 min vs 289 min vs 330 min, P < 0.001), the least blood loss (median 250 ml vs 500 ml vs 1000 ml, P < 0.001) and the fewest packed red blood cells transfusion (median 400 ml vs 800 ml vs 1200 ml, P < 0.001). The ORN-VT group had the highest complication rate (18.2 vs 22.7 vs 43.2%, P = 0.005), the highest Clavien grade (P = 0.001) and the longest postoperative hospital stay (median 7d vs 8d vs 10d, P < 0.001). No significant difference in OS, TSS and MFS between the minimally invasive procedures (MIP, including RALRN-VT and LRN-VT) group and ORN-VT group was found. The hazard ratio of LRFS for the MIP group was 0.20 (95% CI 0.06-0.70, P = 0.01) compared with ORN-VT group.

CONCLUSIONS

RALRN-VT can result in the best surgical outcomes compared with LRN-VT and ORN-VT. The MIP group had a better LRFS compared with ORN-VT group.

[Efficacy comparison among high risk factors questionnaire and Asia-Pacific colorectal screening score and their combinations with fecal immunochemical test in screening advanced colorectal tumor]

Objective: To investigate the effects of high risk factors questionnaire (HRFQ), Asia-Pacific colorectal screening (APCS) score and their combinations with fecal immunochemical test (FIT) in screening advanced colorectal neoplasia, in order to provide an evidence for further optimization of cancer screening program. Methods: A retrospective cohort study method was used to summarize and analyze the results of colorectal tumor screening in Jiashan County, Zhejiang Province from March 2017 to July 2018. Those with severe diseases that were not suitable for colonoscopy and those with mental and behavioral abnormalities who can not cooperate with the screening were excluded. Those who met any one or more of the followings in the HRFQ questionnaire were classified as high-risk people of HRFQ: (1) first-degree relatives with a history of colorectal cancer; (2) subjects with a history of cancer or any other malignant tumor; (3) subjects with a history of intestinal polyps; (4) those with two or more of the followings: chronic constipation (constipation lasted for more than 2 months per year in the past two years), chronic diarrhea (diarrhea lasted for more than 3 months in the past two years, and the duration of each episode was more than one week), mucus and bloody stools, history of adverse life events (occurring within the past 20 years and causing greater trauma or distress to the subject after the event), history of chronic appendicitis or appendectomy, history of chronic biliary disease or cholecystectomy. In this study, those who were assessed as high risk by HRFQ were recorded as "HRFQ (+)", and those who were not at high risk were recorded as "HRFQ (-)". The APCS questionnaire provided risk scores based on 4 risk factors including age, gender, family history and smoking: (1) age: 2 points for 50-69 years old, 3 points for 70 years old and above; (2) gender: 1 point for male, 0 point for women; (3) family history: 2 points for first-degree relatives suffering from colorectal cancer; (4) smoking: 1 point for current or past smoking, 0 point for non-smokers. The population was divided into low-risk (0-1 point), intermediate-risk (2-3 points), and high-risk (4-7 points). Those who were assessed as high risk by APCS were recorded as "APCS (+)", and those with intermediate and low risk were recorded as "APCS (-)". The hemoglobin threshold for a positive FIT was set to 100 μg/L. Those who were assessed as high risk by APCS with positive FIT were recorded as "APCS+FIT (+)". Those who were assessed as high risk by APCS with negative FIT, those who were assessed by APCS as low-middle risk with positive FIT, and those who were assessed by APCS as low-middle with negative FIT were all recorded as "APCS+FIT(-)". Observation indicators in this study were as follows: (1) the screening compliance rate of the cohort and the detection of advanced colorectal tumors; (2) positive predictive value, negative predictive value, sensitivity and specificity of HRFQ and APCS and their combination with FIT for screening advanced colorectal tumors; (3) comparison of the detection rate between HRFQ and APCS questionnaire for different colorectal lesions. Using SPSS 21.0 software, the receiver operating characteristic (ROC) curve was drawn to evaluate the clinical value of HRFQ and APCS combined with FIT in screening advanced colorectal tumors. Results: From 2017 to 2018 in Jiashan County, a total of 53 268 target subjects were screened, and 42 093 people actually completed the questionnaire, with a compliance rate of 79.02%. A total of 8145 cases underwent colonoscopy. A total of 3607 cases among HRFQ positive population (5320 cases) underwent colonoscopy, and the colonoscopy compliance rate was 67. 80%; 8 cases were diagnosed with colorectal cancer and 88 cases were advanced colorectal adenoma. A total of 2977 cases among APCS positive population (11 942 cases) underwent colonoscopy, and the colonoscopy compliance rate was 24.93%; 17 cases were diagnosed with colorectal cancer and 148 cases were advanced colorectal adenoma. The positive rate of HRFQ screening was lower than that of APCS [12.6% (5320/42 093) vs. 28.4% (11 942/42 093), χ²=3195. 547, P<0.001]. In the FIT positive population (6223 cases), a total of 4894 cases underwent colonoscopy, and the colonoscopy compliance rate was 78.64%; 34 cases were diagnosed with colorectal cancer and 224 cases were advanced adenoma. The positive predictive values of HRFQ and APCS and their combination with FIT for screening advanced colorectal tumors were 2.67%, 5.54%, 5.44%, and 8.56%; negative predictive values were 94.89%, 96.85%, 96.11% and 96.99%; sensitivity was 29.27%, 50.30%, 12.20 % and 39.02%; specificity was 55.09%, 64.03%, 91.11% and 82.51%, respectively. The ROC curves constructed by HRFQ, APCS, FIT, HRFQ+FIT and APCS+FIT indicated that APCS+FIT presented the highest efficacy in screening advanced colorectal tumors (AUC: 0.608, 95%CI: 0.574-0.642). The comparison of the detection rates of different colorectal lesions between HRFQ and APCS questionnaires showed that there were no significant differences in detection rate of inflammatory polyps and hyperplastic polyps between the two questionnaires (both P>0.05). However, as compared to HRFQ questionnaire, APCS questionnaire had higher detection rates in non-advanced adenomas [26.10% (777/2977) vs. 19.43% (701/3607), χ²=51.228, P<0.001], advanced adenoma [4.97% (148/2977) vs. 2.44% (88/3607), χ²=30.249, P<0.001] and colorectal cancer [0.57% (17 /2977) vs. 0.22% (8/3607), χ²=5.259, P=0.022]. Conclusions: APCS has a higher detection rate of advanced colorectal tumors than HRFQ. APCS combined with FIT can further improve the effectiveness of advanced colorectal tumor screening.

Transmutation of long-lived fission products in an advanced nuclear energy system

Disposal of long-lived fission products (LLFPs) produced in reactors has been paid a lot attention for sustainable and clean nuclear energy. Although a few transmutation means have been proposed to address this issue, there are still scientific and/or engineering challenges to achieve efficient transmutation of LLFPs. In this study, we propose a novel concept of advanced nuclear energy system (ANES) for transmuting LLFPs efficiently without isotopic separation. The ANES comprises intense photoneutron source (PNS) and subcritical reactor, which consist of lead–bismuth (Pb-Bi) layer, beryllium (Be) layer, and fuel, LLFPs and shield assemblies. The PNS is produced by bombarding radioactive cesium and iodine target with a laser-Compton scattering (LCS) γ-ray beam. We investigate the effect of the ANES system layout on transmutation efficiency by Monte Carlo simulations. It is found that a proper combination of the Pb-Bi layer and the Be layer can increase the utilization efficiency of the PNS by a factor of ~ 10, which helps to decrease by almost the same factor the LCS γ-beam intensity required for driving the ANES. Supposing that the ANES operates over 20 years at a normal thermal power of 500 MWt, five LLFPs including ⁹⁹Tc, ¹²⁹I, ¹⁰⁷Pd, ¹³⁷Cs and ⁷⁹Se could be transmuted by more than 30%. Their effective half-lives thus decrease drastically from ~ 10⁶ to less than 10² years. It is suggested that this successful implementation of the ANES paves the avenue towards practical transmutation of LLFPs without isotopic separation.

Nontuberculous mycobacteria in China: incidence and antimicrobial resistance spectrum from a nationwide survey

Background

Information on the prevalence and resistance spectrum of nontuberculous mycobacteria (NTM) in China is mainly based on regional or local data. To estimate the proportion of NTM cases in China, a national survey of NTM pulmonary disease was carried out based on acid-fast positive sputum samples collected in 2013.

Methods

Sputum samples collected from enrolled presumptive cases in 72 nationwide tuberculosis surveillance sites from the 31 provinces in the mainland of China were cultured using L-J medium at the National tuberculosis reference laboratory (NTRL). MALDI-TOF MS identified the species of re-cultured strains, and minimal inhibitory concentrations (MICs) were determined to evaluate the drug susceptibility of NTM isolates. Data analysis used statistical software SPSS version 22.0 for Windows statistical package.

Results

Of 4917 mycobacterial isolates cultured, 6.4% [317/4917, 95% confidence interval (CI) 5.8%–7.2%] were confirmed as NTM, among which 7.7% (287/3709, 95% CI 6.9%–8.6%) were from the southern region. In inland and coastal China, 87.7% (95% CI 78.7%–93.2%) and 50.0% (95% CI 43.7%–56.3%) of isolates, respectively, were slow-growing mycobacteria (SGM), with the remaining rapid growing mycobacteria (RGM). A total of 29 species were detected, Mycobacterium abscessus had higher clarithromycin-inducible resistance rates than M. massiliense (65.67% vs 2.22%). M. kansasii presented lower resistance rates in linezolid and moxifloxacin than M. avium-intracellulare complex (3.23% vs 66.67%, 0 vs 47.22%) and other SGM (3.23% vs 38%, 0 vs 26%).

Conclusions

More NTM pulmonary disease was observed in the south and coastal China (P < 0.01). SGM was widely distributed, and more RGM are present in southern and coastal China (P < 0.01). The antimicrobial resistance spectrum of different NTM species was significantly different and accurate species identification would be facilitated to NTM pulmonary disease treatment.

[Occurrence and related factors of preterm birth in Guangxi Zhuang Autonomous Region during 2017-2019]

Objective: To investigate the incidence of preterm birth in Guangxi Zhuang Autonomous Region and explore the related factors and their combined effects. Methods: The study subjects were women giving birth to live babies at the monitoring points of critical maternal hospital monitoring system in Guangxi Zhuang Autonomous Region from January 1, 2017 to December 31, 2019. The data of general characteristics (age and marital status), pregnancies (parity, number of previous cesarean delivery, the number of prenatal check and number of fetuses in this pregnancy) and disease conditions (placenta previa, placental abruption, hypertension, diabetes, anemia, and heart disease) were collected, and the incidence of preterm birth were calculated according to the definition of preterm birth set by WHO and China, respectively. Logistic regression model was used to explore the factors associated with premature birth and their combined effects. Results: According to definitions of WHO and China, the cumulative incidence of preterm birth in Guangxi from 2017 to 2019 was 7.45% (16 819/225 727) and 7.34% (16 559/225 727), respectively. Advanced age [≤34 years old as reference, OR (95%CI) of 35-39 and ≥40 years old were 1.36 (1.30-1.42) and 1.61 (1.50-1.74), respectively], unmarried (including divorced or widowed) [OR (95%CI): 1.28 (1.17-1.40)], primiparae [OR (95%CI): 1.34 (1.29-1.40)], previous cesarean section [no previous cesarean section as reference, OR (95%CI) of 1 and ≥2 times of previous cesarean section were 1.30 (1.24-1.36) and 1.85 (1.65-2.08), respectively], antenatal examination<8 [OR (95%CI): 2.72 (2.62-2.81)], multiple pregnancies [OR (95%CI): 15.00 (14.01-16.06)], placenta previa [OR (95%CI): 6.90 (6.35-7.50)], placental abruption [OR (95%CI): 8.18 (7.36-9.10)], gestational hypertension [OR (95%CI): 2.29 (2.17-2.42)], gestational diabetes mellitus [OR (95%CI): 1.43 (1.37-1.49)], anemia [OR (95%CI): 1.10 (1.07-1.14)], and heart diseases [OR (95%CI): 2.98(2.43-3.65)] were all positively correlated with preterm birth. The risk of preterm birth in pregnant women exposed to 1, 2, 3, 4, 5, 6 and ≥7 preterm birth related factors was 1.51, 2.29, 4.49, 9.69, 20.87, 46.88 and 192.11 times that of non-exposed women, respectively (all P values<0.001). Conclusion: Preterm birth is associated with maternal general characteristics, pregnancy and disease status, and the combined effect of preterm birth related factors significantly increases the risk of preterm birth.

Integrative genomic study of Chinese clear cell renal cell carcinoma reveals features associated with thrombus

Clear cell renal cell carcinoma (ccRCC) is a heterogeneous disease with features that vary by ethnicity. A systematic characterization of the genomic landscape of Chinese ccRCC is lacking, and features of ccRCC associated with tumor thrombus (ccRCC-TT) remain poorly understood. Here, we applied whole-exome sequencing on 110 normal-tumor pairs and 42 normal-tumor-thrombus triples, and transcriptome sequencing on 61 tumor-normal pairs and 30 primary-thrombus pairs from 152 Chinese patients with ccRCC. Our analysis reveals that a mutational signature associated with aristolochic acid (AA) exposure is widespread in Chinese ccRCC. Tumors from patients with ccRCC-TT show a higher mutational burden and genomic instability; in addition, mutations in BAP1 and SETD2 are highly enriched in patients with ccRCC-TT. Moreover, patients with/without TT show distinct molecular characteristics. We reported the integrative genomic sequencing of Chinese ccRCC and identified the features associated with tumor thrombus, which may facilitate ccRCC diagnosis, prognosis and treatment.

The genomic heterogeneity of clear cell renal cell carcinoma (ccRCC) across populations is poorly understood. Here, the authors analyse a cohort of Chinese ccRCC cases revealing a mutational signature associated with aristolochic acid exposure, and higher mutational burden and enrichment for BAP1 and SETD2 mutations in ccRCC cases associated with tumor thrombus.

[Construction of prognostic model and identification of prognostic biomarkers based on the expression of long non-coding RNA in bladder cancer via bioinformatics]

OBJECTIVE

To construct the prognostic model and identify the prognostic biomarkers based on long non-coding RNA (lncRNA) in bladder cancer.

METHODS

The lncRNA expression data and corresponding clinical data of bladder cancer were collected from The Cancer Genome Atlas (TCGA) database. The software Perl and R, and R packages were used for data integration, extraction, analysis and visualization. Detailly, R package "edgeR" was utilized to screen differentially expressed lncRNA in bladder cancer tissues compared with the normal bladder samples. The univariate Cox regression and the least absolute shrinkage and selection operator (Lasso) regression were performed to identify key lncRNA that were utilized to construct the prognostic model by the multivariate Cox regression. According to the median value of the risk score, all patients were divided into the high-risk group and low-risk group to perform the Kaplan-Meier (K-M) survival curves, receiver operating characteristic (ROC) curve and C-index, estimating the prognostic power of the prognostic model. In addition, the hazard ratio (HR) and 95% confidence interval (CI) of each key lncRNA were also calculated by the multivariate Cox regression. Moreover, we performed the K-M survival analysis for each significant key lncRNA from the result of the multivariate Cox regression.

RESULTS

A total of 691 lncRNA were identified as differentially expressed lncRNA, and 35 lncRNA signatures were initially considered associated with the prognosis of bladder cancer, where in 23 lncRNA were identified as key lncRNA associated with the prognosis. The overall survival time in years of the low-risk group was obviously longer than that of the high-risk group [(2.85±2.72) years vs. (1.58±1.51) years, P<0.001]. The area under the ROC curve (AUC) was 0.813 (3-year survival) and 0.778 (5-year survival) respectively, and the C-index was 0.73. In addition, HR and 95%CI of each key lncRNA were calculated by the multivariate Cox regression and 11 lncRNA were significant. Furthermore, K-M survival analysis revealed the independent prognostic value of 3 lncRNA, including AL589765.1 (P=0.004), AC023824.1 (P=0.022)and PKN2-AS1 (P=0.016).

CONCLUSION

The present study successfully constructed the prognostic model based on the expression level of 23 lncRNA and finally identified one protective prognostic biomarker AL589765.1, and two adverse prognostic biomarkers including AC023824.1 and PKN2-AS1 in bladder cancer.

[Efficacy and safety of catheter-directed interventional therapy in patients with acute pulmonary embolism]

Objective: To evaluate the efficacy and safety of catheter-directed interventional therapy in patients with acute pulmonary embolism(PE). Methods: PE was diagnosed by CT pulmonary angiography(CTPA). After risk stratification, a total of 79 PE patients (age (58.9±14.9) years old)were treated with catheter-directed interventional therapy via pulmonary vessels. The changes of pulmonary hemodynamics were compared before and after treatment. The risk of complications and side effects were observed. Results: The pulmonary artery pressure was changed followed by interventional therapy. The interventional therapy significantly decreased mean pulmonary arterial pressure (mPAP) from (35.3±11.2)mmHg (1 mmHg=0.133 kPa) to (30.0±10.6)mmHg (t=8.803,P<0.05) and the echocardiographic derived right ventricular dimension to left ventricular dimension (RV/LV) ratio from 0.93±0.16 to 0.83±0.15 (t=6.868,P<0.05). The arterial partial pressure of oxygen was increased from (69.0±8.6)mmHg to (75.1±9.9)mmHg (t=8.561,P<0.05) . The oxygen saturation was also increased from (93.9±2.9)% to (95.1±1.9)% at 24 h after the treatment (t=2.621,P<0.05) . Patients were further grouped as high-risk group (n=28) and intermediate risk group (n=51). mPAP and RV/LV ratio were significantly reduced in the two subgroups (all P<0.05) and the range of reduction was more significant in the high-risk group. Five patients experienced minor bleeding complication, 3 patients suffered worsened dispone post procedure and were treated with mechanical ventilation, 1 patient died, and 1 patient developed recurrent PE. Conclusion: The catheter-directed interventional therapy improves pulmonary hemodynamics and reduces load of right ventricle both in high-risk or intermediate risk PE patients, this therapy strategy is safe and effective for patients with PE.

A 3-year experience of a simple, novel technique for accurate ostial/non-ostial coronary stenting: The buddy balloon anchor stent technique

OBJECTIVE

To evaluate the safety and efficacy of a new technique for accurate ostial/non-ostial coronary stenting in percutaneous coronary intervention (PCI).

BACKGROUND

Accurate stent localization is a key factor impacting the postoperative success of patients undergoing PCI. However, the accurate localization of some lesions, especially ostial lesions, is very difficult to achieve, because they are often complicated by bobbing or to-and-fro movement of the stent during cardiac contractions.

METHODS

We report a novel technique of precise ostial/non-ostial stenting based on the buddy balloon anchor stent (BBAS) technique. Between May 2014 and July 2017, 47 patients with significant ostial/non-ostial coronary stenosis that required accurate stenting were included in this study. Of them, 23 patients were treated using the conventional method and the remaining 24 patients were treated using (BBAS) technique. Evaluation was then performed using intravascular ultrasound (IVUS) in the procedural, or coronary computed tomography angiography (CCTA) in the follow up.

RESULTS

Using the BBAS technique, the procedural success was achieved in all 24 (100%) cases. IVUS was performed in seven patients (29.17%) and no procedural complications occurred. All six failed cases that occurred among patients with right coronary artery and left anterior descending artery ostial stenosis treated using the conventional method, the lesions were subsequently successfully re-stented using the BBAS technique. After a follow-up of 3-36 months, CCTA was performed in 11 patients (45.83%), all the stents were in the accurate position. There were no major cardiovascular events of death, myocardial infarction, or target lesion revascularization.

CONCLUSION

BBAS is a simple, highly successful and safe technique for accurate stenting of difficult ostial/nonostial coronary stenosis lesions.

[Technical improvement in retroperitoneal laparoscopic living donor nephrectomy: report of 193 cases]

OBJECTIVE

To summarize our experience of retroperitoneal laparoscopic living donor nephrectomy, our continuous technical improvements and refinement of this skill and standardization of each procedure of this operation.

METHODS

Having approved by hospital ethical committee and local government administration, a total of 193 living donors underwent retroperitoneal laparoscopic living donor nephrectomy from Dec.2003 to Feb. 2016 in our department. Under general anaesthesia, the operation was performed through 3 lumbar ports. After the kidney was liberated fully and the ureter was severed 7-8 cm under the lower pole of the kidney, the renal artery and vein were blocked with endo-cut or hem-o-lok separately and then severed. Then the kidney was taken out quickly and flushed with 4 °C kidney preserving fluid immediately, the donor kidneys were then preserved in iced saline until kidney transplantation. Clinical data about operation time, volume of blood loss, perioperative complications, renal function of both donors and recipients before and after operation were collected.

RESULTS

The 193 retroperitoneal laparoscopic living donor nephrectomy operations were successful with only one operation was converted to open living donor nephrectomy because of hemorrhage and unclear operation field during the operation. The average operation time was 85 min (55-135 min), the average blood loss was 60 mL (20-200 mL), and no donor needed blood transfusion during or after operation. Three donors were found to have hematoma of renal fossa after operation and none of them required further treatment. The average hospital stay after operation was 5.7 days (4-9 days). In the study, 162 donors were followed up for an average of 42 months (1-58 months) and they were all healthy. Two kidney recipients had urinary bladder anastomosis leakage after operation and both needed surgical repair, a new anastomosis of ureter and bladder were made. Three kidney recipients had kidney subcapsular hematoma but required no further treatment. One kidney recipient had delayed graft function and recovered finally and the renal function of other recipients were all normal. Renal function of both donors and recipients during the follow up period were normal.

CONCLUSION

Retroperitoneal laparoscopic living donor nephrectomy is a safe and reliable technique, it may become a standardized operation for living kidney transplantation after continuous technical improvement. Precautions must be taken to avoid complications and a skilled hand is necessary for success.

[RNA interference targeting DNA-PKcs inhibits glioma cells malignancies and enhances temozolomide sensitivity]

Objective: To investigate the effect of DNA dependent protein kinase catalytic subunit (DNA-PKcs) on glioma proliferation, invasion and temozolomide sensitivity, and also to explore the potential mechanisms. Methods: Human glioma cell lines H4 and U87 were chosen to carry out RNA interference transfection, and then divided into negative control group (blank group) and siRNA group (test group). The knockdown efficacy of DNA-PKcs siRNA was tested by quantitative PCR and Western blot. The MTS assay and Transwell assay were used to investigate the effect of DNA-PKcs knockdown on glioma cell growth and invasion, respectively. We also used MTS assay to investigate the IC(50) value of temozolomide in negative control group and siRNA groups. Result: Compared with blank group, DNA-PKcs specific siRNA significantly downregulated both mRNA and protein level of DNA-PKcs. MTS assay results demonstrated that 72-hours proliferation of test group were only 52.48%, 54.70% (H4) and 52.98%, 50.45% (U87) of the blank group's counterpart. Transwell assay results showed that the invasiveness abilities of blank and test groups were 1.00±0.03, 0.41±0.05, 0.39±0.04 (H4) and 1.00±0.02, 0.28±0.04, 0.27±0.04 (U87). Moreover, knockdown of DNA-PKcs significantly decreased the temozolomide IC(50) value (H4: 249±27, 97±39, 88±35; U87: 485±41, 86±49, 73±38). Further we applied the Western blot to reveal the mechanism of inhibitory effect of DNA-PKcs knockdown on glioma malignancies and temozolomide sensitivity. We found that downregulation of DNA-PKcs reduced the activity of AKT signal and the expression of its downstream effectors, such as c-Myc, MMP9, and Survivin. Conclusion: RNA interference targeting DNA-PKcs could inhibit glioma malignancies and enhance temozolomide sensitivity. The inhibitory effect of DNA-PKcs knockdown on those biological activities were mainly through inhibition of AKT signal and its downstream effectors.

Geometrical shape design of nanophotonic surfaces for thin film solar cells

We present the effect of geometrical parameters, particularly shape, on optical absorption enhancement for thin film solar cells based on crystalline silicon (c-Si) and gallium arsenide (GaAs) using a rigorous coupled wave analysis (RCWA) method. It is discovered that the "sweet spot" that maximizes efficiency of solar cells exists for the design of nanophotonic surfaces. For the case of ultrathin, rod array is practical due to the effective optical resonances resulted from the optimum geometry whereas parabola array is viable for relatively thicker cells owing to the effective graded index profile. A specific value of thickness, which is the median value of other two devices tailored by rod and paraboloid, is optimized by truncated shape structure. It is therefore worth scanning the optimum shape of nanostructures in a given thickness in order to achieve high performance.

Generation of bright attosecond x-ray pulse trains via Thomson scattering from laser-plasma accelerators: errata

We report and correct a couple of calculation errors in the x-ray flux and maximum peak brightness in our paper [Opt. Express 22, 32098 (2014)].

Generation of bright attosecond x-ray pulse trains via Thomson scattering from laser-plasma accelerators

Generation of attosecond x-ray pulse attracts more and more attention within the advanced light source user community due to its potentially wide applications. Here we propose an all-optical scheme to generate bright, attosecond hard x-ray pulse trains by Thomson backscattering of similarly structured electron beams produced in a vacuum channel by a tightly focused laser pulse. Design parameters for a proof-of-concept experiment are presented and demonstrated by using a particle-in-cell code and a four-dimensional laser-Compton scattering simulation code to model both the laser-based electron acceleration and Thomson scattering processes. Trains of 200 attosecond duration hard x-ray pulses holding stable longitudinal spacing with photon energies approaching 50 keV and maximum achievable peak brightness up to 10²⁰ photons/s/mm²/mrad²/0.1%BW for each micro-bunch are observed. The suggested physical scheme for attosecond x-ray pulse trains generation may directly access the fastest time scales relevant to electron dynamics in atoms, molecules and materials.

Relationship between the angle of vertebral screws and spinal lateral angulation after fixation of thoracolumbar fractures via an anterior approach

This study investigated possible contributors to lateral spinal angulation after surgical fixation of thoracolumbar fractures via an anterior approach. We retrospectively examined lateral angulation in 172 cases of thoracolumbar fractures treated in this manner. The coronal Cobb angle and angles of the screws relative to the endplates were determined from radiographs. The patients completed the Short Form 36, Oswestry Disability Index, Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, and Visual Analogue Scale at the final follow-up visit. The mean coronal Cobb angle was 0.75° ± 3.91° (-14.25° to 14.55°) preoperatively, 3.17° ± 4.07° (-8.18° to 14.01°) immediately postoperatively, and 3.46° ± 4.21° (-1.05° to 17.27°) at the final follow-up visit. The superior posterior and inferior anterior screws were more parallel to their respective endplates when the approach was made ≥2 vs ≤1 vertebral levels above the fracture (P < 0.001). Lateral angulation was more likely when the approach was made ≤1 vs ≥2 levels above the fracture (P < 0.001). The coronal Cobb angle differed significantly (P < 0.01) between patients with lumbar and thoracic fractures. The immediate postoperative coronal Cobb angle correlated tightly with the sum of the screw angles (superior plus inferior posterior and/or inferior plus superior anterior). Lateral angulation may occur after surgical fixation of thoracic and lumbar fractures via an anterior approach. Non-parallelism between the vertebral screws and their corresponding endplates may predict postoperative lateral spinal angulation. Postoperative lateral angulation does not correlate with low back pain, quality of life, or preoperative lateral angulation.

Human mesenchymal stromal cells are mechanosensitive to vibration stimuli

Low-magnitude high-frequency (LMHF) vibrations have the ability to stimulate bone formation and reduce bone loss. However, the anabolic mechanisms that are mediated by vibration in human bone cells at the cellular level remain unclear. We hypothesized that human mesenchymal stromal cells (hMSCs) display direct osteoblastic responses to LMHF vibration signals. Daily exposure to vibrations increased the proliferation of hMSCs, with the highest efficiency occurring at a peak acceleration of 0.3 g and vibrations at 30 to 40 Hz. Specifically, these conditions promoted osteoblast differentiation through an increase in alkaline phosphatase activity and in vitro matrix mineralization. The effect of vibration on the expression of osteogenesis-related factors differed depending on culture method. hMSCs that underwent vibration in a monolayer culture did not exhibit any changes in the expressions of these genes, while cells in three-dimensional culture showed increased expression of type I collagen, osteoprotegerin, or VEGF, and VEGF induction appeared in 2 different hMSC lines. These results are among the first to demonstrate a dose-response effect upon LMHF stimulation, thereby demonstrating that hMSCs are mechanosensitive to LMHF vibration signals such that they could facilitate the osteogenic process.

Osteogenic responses of human mesenchymal stromal cells to static stretch

Molecular signals driving the regenerative process in distraction osteogenesis (DO) involve a complex system of cellular behavior triggered by mechanical strain. However, it remains unclear how mesenchymal stromal cells (MSCs) adapt to osteogenic demands during DO. We hypothesized that human MSCs (hMSCs) modulate early osteogenic metabolism during exposure to static stretch. The proliferation of hMSCs was increased by static stretch, which, in turn, suppressed TGF-β1-mediated decreases in cell proliferation. The amount of stretching force applied had little effect on osteoblast differentiation of hMSCs induced by dexamethasone treatment. However, this strain induced sustained production of nitric oxide and vascular endothelial growth factor (VEGF), which are critical factors in angiogenesis, from differentiated hMSCs. Mechanical stretch involved ERK and p38 mitogen-activated protein kinase pathways, the selective inhibitors of which decreased static-stretch-induced VEGF production. These findings provide evidence that hMSCs act to facilitate early osteogenic metabolism during exposure to static stretch.

Light-extraction enhancement of red AlGaInP light-emitting diodes with antireflective subwavelength structures

We demonstrate the enhancement of light extraction in 633 nm AlGaInP light-emitting diodes (LEDs) with antireflective subwavelength structures (SWS). From the contour plots by the rigorous coupled wave analysis method, it is found that the reduction of the internal reflection strongly depends on the period of SWS. The Ag nanoparticles formed by thermal dewetting were used as an etch mask for dry etch process to fabricate antireflective SWS on the LED surface. The tapered pillars on the GaP were fabricated, on average, with distances below 200 nm, satisfying the required antireflection condition at the emission wavelength. The improvement in light output power by approximately 26.4% was achieved for the fabricated AlGaInP LEDs with SWS compared to the conventional LEDs due to a strongly reduced Fresnel internal reflection at the GaP/air interface. The improved directionality in the far-field pattern was also obtained due to the directional light extraction enhancement.

Polyglycolic Acid-islet grafts improve blood glucose and insulin concentrations in rats with induced diabetes

Pancreatic islet transplantation is a promising therapeutic treatment for type 1 diabetes mellitus. In the present study, we cocultured islets with or without a polyglycolic acid (PGA) fibrous scaffold for 5 days and transplanted the PGA-islet grafts into the leg muscles of Wistar rats with streptozotocin-induced diabetes; controls were injected with saline. The results showed that the blood glucose concentrations of the group given islets embedded with the PGA scaffold were lower than those without the scaffold or controls. On the other hand, the insulin content of the PGA-islet group was higher at all 5 time points compared with the insulin contents of the other 2 groups. After transplantation, many islets in the PGA-islet grafts showed normal morphology (as seen under the scanning electron microscope) and were surrounded by red blood cells. A fibrous extracellular matrix was visible around the PGA-islet grafts. These results demonstrated that PGA-islet grafts improved blood glucose and insulin concentrations in rats with induced diabetes.

High-speed characteristics of vertical cavity surface emitting lasers and resonant-cavity-enhanced photodetectors based on intracavity-contacted structure

We fabricated vertical cavity surface emitting lasers (VCSELs) and resonant-cavity-enhanced photodetectors (RCE-PDs) with GaAs/AlGaAs distributed Bragg reflectors (DBRs), operating at lambda approximately 980 nm, based on an intracavity-contacted structure. The top-DBR mesa diameter of the VCSELs was optimized to 18 microm in terms of slope efficiency, differential series resistance, and 3 dB bandwidth. For VCSELs with an oxide aperture of 4.5 microm and a top-DBR mesa diameter of 18 microm, the threshold current was about 1.2 mA, exhibiting maximum output power of approximately 3.49 mW (at 20 degrees C) with good uniformity. The effect of the overetching in the outermost layer of RCE-PDs on the device performance was also investigated. For RCE-PDs based on the VCSEL structure, a peak responsivity of 0.44 A/W (at lambda approximately 979.7 nm) with a spectral width of approximately 3 nm and a dark current of 68 pA under a bias voltage of -5 V at 20 degrees C was obtained. The maximum 3 dB bandwidths of approximately 11.5 GHz with a modulation current efficiency factor of 5.6 GHz/mA(1/2) at -7 mA and 9 GHz at -7 V were achieved for VCSELs and RCE-PDs, respectively.

Adhesive growth of pancreatic islet cells on a polyglycolic acid fibrous scaffold

BACKGROUND

The use of cultured pancreatic islet cells for diabetes treatment offers several advantages. In theory, cultured cells show greater purity and lower immunogenicity. However, cultured islet cells display a low survival rate in vitro. In the present study we grew islet cells on a polyglycolic acid (PGA) fibrous scaffold to promote cell adhesion, growth, and viability during prolonged culture.

METHODS

Islets isolated from Wistar rat pancreata were digested with collagenase and purified by the Ficoll method. Cells were grown in culture with or without PGA scaffolds. Islet cell purity was determined using a dithizone stain; viability and survival rates were determined using an AO-PI stain. The insulin-secretion index was detected using radioimmunodetection and the growth on an adhesive scaffold analyzed using an inverted microscope and scanning electron microscope (SEM).

RESULTS

In contrast to the scaffold-free control group, cells cultured on PGA scaffolds exhibited improved morphology, less cell death, and prolonged survival times. Cell viability and survival rates were significantly increased in scaffolded cells when compared to control cells (P < .05). Increased insulin secretion was observed in the culture solution of scaffolded cells following stimulation with low glucose (5.6 mmol/L) versus high glucose (16.7 mmol/L). The secretion indices of the two groups were significantly different (P < .05). Islet cell growth, as observed under SEM, was tightly circumvolute, adhesive, and three-dimensional.

CONCLUSIONS

The present results demonstrated that islet cells can successfully grow and survive in culture on a PGA scaffold. These cells exhibited enhanced viability, survival, and insulin secretion.

Correlation of ventricular asymmetry with metabolic asymmetry in frontotemporal dementia

BACKGROUND AND PURPOSE

The clinical presentation of frontotemporal dementia (FTD) is often asymmetrical in terms of both its clinical features and atrophy on MRI. Asymmetry in the lateral ventricle size on structural neuroimaging in FTD patients may have clinical significance. However, this has not been systematically investigated yet. This study compares the ventricular asymmetry seen on MRI with that of the asymmetric glucose metabolism using FDG-PET in patients with FTD.

METHODS

Nineteen FTD patients who underwent both brain MRI and FDG-PET were retrospectively selected. As control groups, 23 and 11 age and sex-matched healthy normal subjects underwent either brain MRI or FDG-PET, respectively. The ventricular asymmetry index (VAI) was obtained in two ways: by visual rating (VAI-V) and by measuring the lateral ventricular volumes (VAI-ROI). The hemispheric asymmetry of the glucose metabolism on FDG-PET (MAI) was assessed in three ways: 1) by visual rating (MAI-V), 2) by counting the FDG activity of each hemisphere on normalized and smoothed PET images (MAI-ROI) and 3) by counting the number of voxels with significant hypometabolism based on statistical parametric mapping results (MAI-SPM).

RESULTS

The VAIs on MRI (VAI-V and VAI-ROI) were highly correlated, as were the MAIs (MAI-V, MAI-ROI, and MAI-SPM) on FDG-PET. More importantly, the VAIs on MRI and the MAIs on FDG-PET showed high correlation.

CONCLUSIONS

Ventricular asymmetry in FTD patients was common (78.9%) and there was a high correlation between the ventricular structural asymmetry and the hemispheric metabolic asymmetry. Therefore, it would be reasonable to interpret that the hemisphere with larger ventricle on MRI in FTD patients is undergoing a more active degenerative process.

Trends in socio-economic differentials in cigarette smoking behaviour between 1990 and 1998: a large prospective study in Korean men

OBJECTIVES

To investigate the magnitude and time trends in socio-economic differentials in cigarette smoking behaviour.

STUDY DESIGNS

A prospective observational study of male civil servants followed-up for 8 years.

SETTING

All civil service offices in Korea.

PARTICIPANTS

A total of 322,991 male civil servants aged 30-49 years on whom information on monthly salary was available and who had reported cigarette smoking behaviour between 1990 and 1998.

RESULTS

Smoking prevalence was 60.1% in 1990 and was inversely associated with salary level. The difference in smoking prevalence between the highest and the lowest salary groups gradually widened from 13.0% in 1990 to 16.1% in 1998. The relative index of inequality (RII) as a measure of socio-economic inequality in smoking behaviour was 1.91 [95% confidence interval (CI) 1.86-1.97] in 1990 and increased between 1990 and 1998. The RII for smoking cessation was 0.60 in 1990 (95% CI 0.58-0.62) and gradually decreased as time lapsed.

CONCLUSIONS

An increasing trend in socio-economic inequality in smoking behaviour was observed in this study.

Effects of selected minerals on leptin secretion in streptozotocin-induced hyperglycemic mice

The effects of lithium, magnesium, vanadate, and zinc on leptinemia and leptin secretion by adipose tissue were investigated in streptozotocin- (STZ) induced hyperglycemic mice. After the administration of studied minerals in drinking water for 4 weeks, fasting serum leptin concentrations were elevated, accompanied by normoglycemia in STZ-injected mice, regardless which mineral was provided (P < 0.05). However, the in vitro administration of lithium, magnesium, and vanadate did not significantly influence the leptin secretion of adipose tissue. A low zinc treatment (0.1 mM) augmented, whereas both a pharmacological treatment of zinc (1 mM) and zinc depletion (1 mM TPEN) attenuated, leptin secretion (P < 0.05). The present study shows that STZ-induced hyperglycemic mice have hypoleptinemia and reduced leptin secretion by adipose tissue. Moreover, these defects can be improved by a moderate zinc administration.

[Use of intraoperative red blood cell salvage in the anterior stabile operation of spinal fracture]

OBJECTIVE

To observe the clinical results in the anterior stabile operation of spinal fracture using red blood salvage.

METHODS

Nineteen cases with spinal fracture were performed the anterior decompress operation. Blood cell salvage were used during operation. Other 20 cases were also reviewed as control group, who were received the same operation without blood cell salvage.

RESULTS

In the 19 cases, average volume of autologous transfusion was 536 ml. Only two cases had homologous transfusion requirements. In the control group, all cases needed homologous transfusion (averaged 947 ml).

CONCLUSION

In the anterior decompress operation, the intraoperative blood salvage is highly effective in reducing transfusion and also improves the security of operation.

Body mass index and mortality: a twelve-year prospective study in Korea

The relation between body mass index (kg/m2) and noncoronary mortality is not well established. To study this relation, a population with low coronary mortality may be especially useful. We conducted a 12-year follow-up study of 235,398 Korean men 40-64 years of age. Study subjects had undergone health examinations in 1986 (baseline) and 1990. We excluded subjects with substantial weight loss during this period. There were 13,387 deaths, including 600 deaths from coronary events, between 1990 and 1998. We estimated the relation of body mass index to the risk of death after adjusting for common risk factors. There was a positive relation between body mass index and coronary mortality, but this relation was attenuated after serum total cholesterol, blood pressure, and fasting serum glucose were taken into account. A J-shaped relation with cerebrovascular mortality was also attenuated after adjustment. Even after this adjustment and exclusion of early deaths between 1990 and 1994, the relation of body mass index to all-cause (U-shaped), cancer (J-shaped), and noncancer noncoronary noncerebrovascular (inverse J-shaped) mortality remained. Both high and low body mass index were related to increased mortality among these Korean men.

Acute biochemical variations induced by calcium citrate and calcium carbonate in Type 2 diabetic patients: impaired calcium absorption in Type 2 diabetic patients with prolonged gastric emptying time

Calcium supplementation is important in the treatment of osteoporosis, a disease that may also occur in diabetic patients. The acute effects of calcium supplementation and their relationship to gastric emptying time, however, have rarely been studied in type 2 diabetic patients. We evaluated the acute biochemical variations induced by the administration of two different calcium preparations, calcium citrate and calcium carbonate, in 16 (male/female: 13/3) Chinese diabetic patients. Serum free calcium, intact parathyroid hormone (i-PTH), and amount of urinary excretion of calcium (uCal/uCr) were evaluated after a single dose of 1200 mg of elemental calcium in each preparation. The free calcium levels did not change significantly in either group. However, significant suppression of i-PTH after calcium citrate administration at 1 h (17.1+/-2.0 pg/ml, P=.023), and after calcium carbonate administration at 2 h (14.2+/-2.5 pg/ml, P=.000), was noted when compared with individual basal level (21.2+/-2.5 and 19.3+/-2.4 pg/ml, respectively). The suppressive effect on i-PTH lasted for 6 h after calcium citrate and 5 h after calcium carbonate preparation of the 6-h study period. After administration of calcium citrate, the uCal/uCr of 2-to-4-h collection was significantly higher than that of the basal and 0-to-2-h collections: 0.25+/-0.04 vs. 0.19+/-0.03, P=.025; and 0.25+/-0.04 vs. 0.19+/-0.02, P=.014, respectively. A similar finding was observed for calcium carbonate: 0.23+/-0.03 vs. 0.18+/-0.02, P=.019; and 0.23+/-0.03 vs. 0.18+/-0.02, P=.011, respectively. We conclude that, in this group of Chinese type 2 diabetic patients in our study, the oral administration of 1200 mg elemental calcium in either calcium citrate or calcium carbonate preparation can induce a significant suppression of i-PTH. This may be helpful in preventing or treating osteoporosis. A prolonged gastric emptying time in these diabetic subjects may contribute to the non-significant alteration in free calcium levels after the administration of either calcium preparation.

Short-term safety and tolerability of antihypertensive agents in Korean patients: an observational study

PURPOSE

In order to assess the short-term safety and tolerability of newly prescribed antihypertensive monotherapies in Korean patients, a prospective study was carried out.

METHODS

A total of 1181 patients were observed from July 1997 to August 1999. At 2, 4, 8 and 12 weeks after initiation of antihypertensive monotherapy, the patients were evaluated for whether treatment was to be continued and the development of any adverse reactions.

RESULTS

During the first 12 weeks, the percentage of subjects continuing with their initial angiotensin converting enzyme inhibitors (ACEI) (40.7%) was substantially lower than that of subjects continuing with angiotensin II receptor antagonists (ARA) (66.2%), alpha-blockers (63.0%), calcium channel blockers (CCB) (61.3%), beta-blockers (55.8%), and diuretics (53.5%), respectively (P < 0.01). The following adverse reactions were detected: cough (7.5%), headache (6.1%), dizziness (3.9%), flushing (3.7%) and impotence (2.4%). Cough, headache, and flushing were more frequent in women, and impotence and loss of libido were more frequent in men (P < 0.05). The incidence of cough associated with ACEI (27.9%) was higher than that associated with the other classes of drugs (P < 0.01).

CONCLUSIONS

The tolerability of antihypertensive medication was highest in Korean patients treated with ARAs, followed by CCBs, beta-blockers, diuretics, alpha-blockers, and ACEIs. The incidences of adverse reactions were different by sex, age and drug class.

Plasma concentrations of leptin and selected minerals do not differ in Type 2 diabetic patients with or without sulfonylurea inefficacy

The oral hypoglycemic agent sulfonylurea (SU) can increase plasma leptin concentrations. Additionally, diabetic subjects frequently have an altered plasma status of selected minerals. However, whether these described plasma parameters are changed in Type 2 diabetic patients who exhibit SU inefficacy has not yet been evaluated. In this preliminary study, fasting blood samples were collected from 16 Type 2 diabetic patients with secondary SU failure. As controls, 16 sex-, age- and adiposity-matched diabetic patients, who had similar diabetic duration and optimal glycemic control by SU, were also recruited. The results show that plasma values of leptin, C-peptide, calcium, magnesium, copper, and zinc did not significantly differ in these diabetic patients with or without secondary SU failure. However, the gender effect on plasma leptin level and the correlations between leptin and adiposity and C-peptide were retained. This study indicates that there is no relation between SU inefficacy and the plasma status of leptin and selected minerals.

Effect of zinc on cellular levels of calmodulin and cyclic adenosine monophosphate in the adipocyte

A perturbation of zinc metabolism has been noted in subjects with obesity. Zinc may also participate in the intracellular signal cascade by affecting cellular calcium influx and a change in the calcium-calmodulin (CaM)-cyclic adenosine monophosphate (cAMP) pathway. The possible effects of zinc on cellular concentrations of CaM, a major cytosolic calcium-binding protein, in the adipocytes derived from obese (ob/ob) mice and their lean counterparts were studied. Adipocytes derived from both phenotypes of mice were treated either with 0.2 mM of zinc sulfate or without any additive for 1 h of incubation; the cellular levels of CaM and cAMP were then determined. The results showed that the obese mice had lower CaM and cAMP levels in their adipocytes compared to the lean mice. Zinc treatment reduced CaM and increased cAMP levels in all mice, although this effect was more pronounced in the lean mice. This study indicated that there was an inverse interaction between CaM and cAMP in their cellular levels in the mouse adipocytes and that might be affected by exogenous zinc addition.

Methylprednisolone increases plasma leptin levels in Graves' hyperthyroidism patients with active Graves' ophthalmopathy

Whether leptin, a product of the ob gene, can be stimulated by glucocorticoid administration has been an issue of controversy. We investigated the effect of intravenous administration of methylprednisolone (500 mg/day x 3 days) on plasma levels of leptin in 16 patients (female/male = 11/5) with Graves' hyperthyroidism and active ophthalmopathy who received pulse therapy. Significant elevation of plasma leptin levels started at the eighth hour (13.9+/-1.8 ng/mL, p=0.042) and lasted until the 72nd hour (21.2+/-5.0 ng/mL, p=0.009), as compared with basal levels (8.8+/-1.2 ng/mL). When methylprednisolone was replaced with oral prednisolone (10 mg three times per day x 2 weeks), no difference in plasma leptin levels was noted compared with basal measurement. Under methylprednisolone administration, a significant suppression of tumor necrosis factor-alpha began at the 24th hour (8.1+/-1.3 pg/mL, p=0.004) and lasted until the 48th hour (8.1+/-1.0 pg/mL, p=0.008), as compared with basal measurement (12.5+/-1.5 pg/mL). Compared with basal levels (93+/-2 mg/dL), significant elevation in the plasma glucose level started at the third hour (135+/-10 mg/dL, p=0.000) and lasted until the 72nd hour (110+/-4 mg/dL, p=0.019). The timing of serum insulin elevation approximated that of plasma glucose (3 hours: 14+/-3 microU/mL, p=0.006) and lasted until the end of prednisolone administration (2 weeks: 12+/-2 microU/mL, p=0.044), when compared with basal levels (14+/-3 microU/mL). We concluded that the parental administration of pharmacological doses of methylprednisolone to patients with Graves' hyperthyroidism could acutely raise their plasma level of leptin.

Tertiary hyperparathyroidism in X-linked hypophosphatemic rickets

We report a case of tertiary hyperparathyroidism in an X-linked familial hypophosphatemic rickets (XLH) patient under regular calcitriol and self-adjusted large doses of oral phosphate salt (2.4-3.6 g/day in 4-5 divided doses) according to his serum phosphate level. Tertiary hyperparathyroidism is an unusual complication of XLH patients during treatment. As there is growing evidence that a high phosphate diet may induce hyperplasia of the parathyroid glands, it is important to avoid the stimulation of the parathyroid glands by high doses of phosphate administration in XLH patients. Serum calcium, phosphate, alkaline phosphatase, and also parathyroid hormone should be measured regularly in order to facilitate an early diagnosis of secondary hyperparathyroidism during the treatment of XLH patients, since this stage is reversible with calcitriol and reduced doses of phosphate salt.

Zinc may be a mediator of leptin production in humans

Obese individuals have hyperleptinemia and hypozincemia. Moreover, leptin and zinc have circadian changes in circulating concentrations. We investigated their possible interaction and examined whether a difference existed between obese men and their lean controls. The results indicated the pattern of circadian change in plasma zinc and leptin did not markedly differ between the obese subjects and the lean controls. However, the obese had higher leptin and lower zinc plasma values at each sampling time than did the lean controls. Because an inverse correlation was found in plasma values between zinc and leptin (r=-0.51, p=0.012), we further determined the role zinc might play in leptin production by human subcutaneous adipose tissue from female donors. The in vitro study showed that zinc treatment (0.2 mmol/L) significantly increased leptin production (142%), however, this increment did not surpass that by insulin (10 nmol/L). The data of this study suggest an interactive connection between zinc and leptin.

Which cholesterol level is related to the lowest mortality in a population with low mean cholesterol level: a 6.4-year follow-up study of 482,472 Korean men

To evaluate the relation between low cholesterol level and mortality, the authors followed 482,472 Korean men aged 30-65 years from 1990 to 1996 after a baseline health examination. The mean cholesterol level of the men was 189.1 mg/100 ml at the baseline measurement. There were 7,894 deaths during the follow-up period. A low cholesterol level (<165 mg/100 ml) was associated with increased risk of total mortality, even after eliminating deaths that occurred in the first 5 years of follow-up. The risk of death from coronary heart disease increased significantly in men with the highest cholesterol level (> or =252 mg/100 ml). There were various relations between cholesterol level and cancer mortality by site. Mortality from liver and colon cancer was significantly associated with a very low cholesterol level (<135 mg/100 ml) without any evidence of a preclinical cholesterol-lowering effect. With lengthening follow-up, the significant relation between a very low cholesterol level (<135 mg/100 ml) and mortality from stomach and esophageal cancer disappeared. The cholesterol level related with the lowest mortality ranged from 211 to 251 mg/100 ml, which was higher than the mean cholesterol level of study subjects.

Pituitary tumor cosecreting thyrotropin and prolactin causing hyperthyroidism--a case report

We report a case of a pituitary tumor cosecreting thyrotropin and prolactin with clinical manifestation of thyrotoxicosis, which is a very rare clinical disorder. Octreotide therapy is effective in suppressing the secretion of thyrotropin, prolactin, and thyroid hormones, and by this, renders relief of symptoms and complications of thyrotoxicosis.

Effect of acarbose administration on plasma concentrations of zinc and copper in patients with NIDDM

Acarbose reduces the intestinal absorption of dietary carbohydrate, thereby ameliorating postprandial hyperglycemia in diabetes mellitus. Dietary carbohydrate can modulate the bioavailability of some trace minerals like zinc and copper. Deficiencies in these minerals are associated with glucose intolerance. It is still unknown whether acarbose's reduction of intestinal carbohydrate absorption causes the short supply of these minerals. Thus, we investigated the changes in plasma zinc and copper levels in patients with NIDDM, after administration of acarbose for 3 months. The results showed that acarbose did not significantly affect fasting and postprandial plasma levels of these minerals, even after acarbose withdrawal. This study indicated that acarbose administration in NIDDM patients over a 3-month period does not influence plasma levels of zinc or copper.

Determination of proteins by fluorescence quenching of Magdala Red

Magdala Red (MR) binding to protein causes a decrease in the fluorescence intensity of MR at 556 nm. Based on this, a new quantitative determination method for proteins is developed. The linear range of this assay is 0.1-4.0 microg ml(-1) of Bovine Serum albumin (BSA). The measurements can be made easily on a common fluorimeter. The reaction between MR and proteins is completed in 1 min, and the fluorescence intensity is stable for at least 2 h. There is little or no interference from amino acids and most metal ions. The proposed method has been applied to the determination of protein in milk powder and soybean milk powder and the results are in agreement with the results by the other methods.

Excess mortality from avoidable and non-avoidable causes in men of low socioeconomic status: a prospective study in Korea

STUDY OBJECTIVE

The objective of this study was to evaluate the magnitude and contributory factors of socioeconomic differentials in mortality in a cohort of Korean male civil servants.

DESIGN

A prospective observational study of male civil servants followed up for five years after baseline measurement.

SETTING

All civil service offices in Korea.

PARTICIPANTS AND MEASUREMENTS

The study was conducted on 759,665 Korean male public servants aged 30-64 at baseline examination in 1992. The grade of monthly salary of these participants divided into four groups, a proxy indicator of socioeconomic status (SES), was the main predictive variable. Mortality of the participants was followed up from 1992 to 1996. The causes of deaths were categorised into four groups according to the medical amenability: avoidable, partly avoidable, non-avoidable, and external causes of death. The risk of mortality associated with SES was estimated using the Cox proportional hazard model.

MAIN RESULTS

Lowest SES group had significantly higher risk of mortality from most causes compared with the highest SES group in the order of external cause (relative risk (RR): 2.26), avoidable (RR: 1.65), all cause (RR: 1.59), and non-avoidable mortality (RR: 1.54). With the adjustment of known risk factors, significantly higher risks of mortality in lowest SES group were attenuated but persisted. Looking at the deaths from partly avoidable causes, significantly higher risks of mortality in the lowest SES group was observed from cerebrovascular disease but not from coronary heart disease.

CONCLUSIONS

Socioeconomic differentials in non-avoidable as well as avoidable mortality, persisting even under the control of risk factors, suggest that mortality is influenced not only by the quality of health care and different distribution of risk factors but also by other aspects of SES that are yet unknown.

Zinc effects on hyperglycemia and hypoleptinemia in streptozotocin-induced diabetic mice

Zinc has an antihyperglycemic effect. Zinc can also influence the production of leptin, a satiety factor that reduces appetite and blood sugar level. In this study, we investigated the effect of zinc supplementation on food intake and circulating leptin and glucose concentrations in streptozotocin-induced diabetic mice. Male diabetic mice received zinc supplementation (20 ppm) from drinking water for two weeks. The results showed that zinc treatment did not affect body weight gain, body fat content or food intake in these diabetic mice. However, zinc supplementation markedly ameliorated the hyperglycemia of diabetic mice. After zinc treatment, serum leptin concentrations tended to increase in the diabetic mice. This study suggests that zinc is a mediator of leptin production.

The occurrence of diabetic ketoacidosis in adults

OBJECTIVE

To analyze the occurrence of DKA in Chinese adults.

METHODS AND PATIENTS

We retrospectively reviewed the medical records of adults presenting with DKA in a tertiary referral center from January 1992 to December 1997. We classified these patients into 3 groups: type 1, type 2 and new-onset diabetes. Clinical features and follow-up treatment were analyzed.

RESULTS

One hundred and twenty patients with 141 episodes of DKA were included; 77 episodes (54.6%) were classified as being caused by type 2, 32 (22.7%) by type 1 and 32 (22.7%) by new-onset DM. The average age of type 2 patients was significantly higher. Of the 25 new-onset patients with follow-up for at least 12 months, 11 were not taking insulin. Of these 11 patients, 6 had a family history of DM and 5 had BMI greater than 26.4 kg/m2. The fasting plasma C-peptide values at various times of follow-up varied from 2.3 to 9.5 ng/ml in 6 of the 11 DKA-onset patients.

CONCLUSION

In type 2 patients, the occurrence of DKA is usually associated with old age and another severe illness. "DKA-onset type 2 DM" reported in African-Americans and in Japanese is also observed in Chinese.

Leptin concentration and the Zn/Cu ratio in plasma in women with thyroid disorder

We investigated the possible correlation between the leptin concentration and the Zn/Cu ratio in the plasma of women with thyroid disorder. Forty women with hypothyroidism (n = 20) or hypothyroidism (n = 20) and 20 euthyroid controls were recruited. The results showed that the women with thyroid disorder (hypothyroidism or hyperthyroidism) had higher plasma leptin concentrations than the normal controls (p < 0.05). Moreover, the plasma leptin concentration had no correlation with plasma thyroid hormone levels in the separate groups, nor among all the participants considered together. A strong correlation (p < 0.005) between leptin and adiposity was only observed in euthyroid women. Plasma values of Zn and Cu and the Zn/Cu ratio were not markedly different among women with altered thyroid status. However, a weak correlation (r = 0.28, p = 0.032) between leptin and the Zn/Cu ratio was found from the pooled data of all participants and retained after adjustment for adiposity. We suggest that there may exist an interaction between the plasma leptin level and thyroid hormone-induced abnormality for selected minerals.

[Resection of odontoid process by transoccipitocervical posterolateral approach to treat old atlantoaxial dislocation]

OBJECTIVE

To explore a new surgical treatment of old atlantoaxial dislocation.

METHODS

5 patients aged 12 to 45 years, who suffered from old atlantoaxial dislocation for 1 to 4.5 years, received the new surgical treatment by the transoccipitocervical posterolateral approach, and expansion of the foramen magnum, odontectomy and bony fusion of the occipitoatlantoid region were performed. Neurological examinations and CT scan were undertaken after operation.

RESULTS

All 5 patients survived. Sensory function recovered almost completely and motor function was better more than 1 degree. CT scan showed the diameter of the spinal canal restored well.

CONCLUSION

The transoccipitocervical posterolateral approach is an ideal and safe pathway to reach the site of old atlantoaxial dislocation and the operating field is exposed completely. Anterior-posterior decompression and occipitocervical spinal fusion can be performed simultaneously.