[Comparison of risk factors for hemorrhagic stroke and ischemic stroke, a prospective long-term follow-up cohort study]

Objective: To analyze and compare the risk factors for hemorrhagic stroke and ischemic stroke and understand the exposure levels in population. Methods: A cohort study of risk factors of stroke was conducted in a rural community in Fengxian District of Shanghai in 2003, and the common risk factors of stroke were investigated at baseline survey, the cerebrovascular hemodynamics indexes were detected, the cerebrovascular function score was calculated according to the unified integral rule, and the incidence of stroke was observed in follow up. The risk factors for hemorrhagic stroke and ischemic stroke were analyzed by cohort study. The risk factors for two subtypes of stroke were compared. Result: A total of 10 565 participants were included in the study, with a mean follow-up period of (11.15±2.26) years, and 103 hemorrhagic stroke cases and 268 ischemic stroke cases were observed during follow-up period. The independent risk factors of hemorrhagic stroke included decreased cerebrovascular function score [hazard ratio (HR)=1.56, 95%CI: 1.23-1.98], history of alcohol consumption (HR=2.46, 95%CI: 1.39-4.34), hypertension (HR=1.75, 95%CI: 1.00-3.07) and older age (HR=1.07, 95%CI: 1.04-1.10). The independent risk factors of ischemic stroke included decreased cerebrovascular function score (HR=1.43, 95%CI: 1.25-1.65), smoking history (HR=1.52, 95%CI: 1.13-2.05), hypertension (HR=1.51, 95%CI: 1.10-2.07), family history of stroke (HR=1.89, 95%CI: 1.13-3.15), left ventricular hypertrophy (HR=1.74, 95%CI: 1.07-2.81) and older age (HR=1.07, 95%CI: 1.05-1.08). Conclusions: Decreased cerebrovascular function score, hypertension, and older age were common independent risk factors of both types of stroke, alcohol consumption history was an independent risk factor of hemorrhagic stroke, and smoking history, and family history of stroke and left ventricular hypertrophy were independent risk factors of ischemic stroke.

Characteristics of flight delays during solar flares

Solar flares are one of the severest solar activities that have important effects on near-Earth space. Previous studies have shown that flight arrival delays increase as a result of solar flares, but the intrinsic mechanism behind this relationship is still unknown. In this study, we conducted a comprehensive analysis of flight departure delays during 57 solar X-ray events by using a huge amount of flight data (~ 5 × 10⁶ records) gathered over a 5-year period. It is found that the average flight departure delay time during solar X-ray events increased by 20.68% (7.67 min) compared to quiet periods. Our analysis also revealed apparent time and latitude dependencies, with flight delays being more serious on the dayside than on the nightside and longer (shorter) delays tending to occur in lower (higher) latitude airports during solar X-ray events. Furthermore, our results suggest that the intensity of solar flares (soft X-ray flux) and the Solar Zenith Angle directly modulate flight departure delay time and delay rate. These results indicate that communication interferences caused by solar flares directly affect flight departure delays. This work expands our conventional understanding of the impacts of solar flares on human society and provides new insights for preventing or coping with flight delays.

[Association between mild cognitive impairment and all-cause mortality in elderly population in China: a Meta analysis]

Objective: To quantitatively evaluate the association between mild cognitive impairment and all-cause mortality. Methods: The research papers of the association between cognitive impairment and all-cause mortality in the elderly in the databases of PubMed, EMBASE, Wang Fang data and CNKI published as of August 1, 2021 were comprehensively retrieved. Software R 4.02 was used for Meta-analysis. Results: A total of 9 research papers were included, involving 48 709 patients. The quality of included papers was high. The results of Meta-analysis showed that the association between mild cognitive impairment and the increased risk of all-cause mortality was statistically significant. Compared with the normal cognitive population, the risk of mortality in the elderly with mild cognitive impairment increased by 39% (HR=1.39, 95%CI: 1.18-1.63). Conclusions: The current research evidence showed that mild cognitive impairment assessed by MMSE screening scale can be used as an independent predictor of the increased risk of all-cause mortality in the elderly population in China. However, due to the limitation of the number of included studies and sample size, the conclusions need to be supported by more evidence studies.

[Fitting and predicting trend of COVID-19 by SVEPIUHDR dynamic model]

Objective: To fit and predict the trend of COVID-19 epidemics in the United States (USA) and the United Kingdom (UK), and analyze the effect of vaccination. Methods: Based on the SEIR dynamic model, considering the presymptomatic infections, isolation measures, vaccine vaccination coverage, etc., we developed a SEIR with vaccine inoculation, Presymptomatic infectious, unconfirmed infectious, hospital isolation and domiciliary isolation dynamics model. The publicly released incidence data of COVID-19 from November 6, 2020 to January 31, 2021 in USA and from November 23, 2020 to January 31, 2021 in UK were used to fit the model and the publicly released incidence data of COVID-19 from February 1, 2021 to April 1 were used to evaluate the predicting power of the model by software R 4.0.3 and predict changes in the daily new cases in the context of different vaccination coverage. Results: According to the cumulative confirmed cases, the fitting bias and the predicting bias of the SVEPIUHDR model for USA and UK were less than 5%, respectively. From the model prediction results, the cumulative cases after COVID-19 vaccination in USA in early April reached 31 864 970. If there had not had such vaccination, the cumulative cases of COVID-19 would have reached to 35 317 082, with a gap of more than 3.4 million cases. In UK, the cumulative cases of COVID-19 after the vaccination was estimated to be 4 195 538 in early April, compared with 4 268 786 cases if no COVID-19 vaccination had been provided, there would have heen a gap of more than 70 000 cases. Conclusion: SVEPIUHDR model shows a good prediction effect on the epidemic of COVID-19 in both USA and UK.

Lack of Myosin X Enhances Osteoclastogenesis and Increases Cell Surface Unc5b in Osteoclast-Lineage Cells

Normal bone mass is maintained by balanced bone formation and resorption. Myosin X (Myo10), an unconventional "myosin tail homology 4-band 4.1, ezrin, radixin, moesin" (MyTH4-FERM) domain containing myosin, is implicated in regulating osteoclast (OC) adhesion, podosome positioning, and differentiation in vitro. However, evidence is lacking for Myo10 in vivo function. Here we show that mice with Myo10 loss of function, Myo10^m/m , exhibit osteoporotic deficits, which are likely due to the increased OC genesis and bone resorption because bone formation is unchanged. Similar deficits are detected in OC-selective Myo10 conditional knockout (cko) mice, indicating a cell autonomous function of Myo10. Further mechanistic studies suggest that Unc-5 Netrin receptor B (Unc5b) protein levels, in particular its cell surface level, are higher in the mutant OCs, but lower in RAW264.7 cells or HEK293 cells expressing Myo10. Suppressing Unc5b expression in bone marrow macrophages (BMMs) from Myo10^m/m mice by infection with lentivirus of Unc5b shRNA markedly impaired RANKL-induced OC genesis. Netrin-1, a ligand of Unc5b, increased RANKL-induced OC formation in BMMs from both wild-type and Myo10^m/m mice. Taken together, these results suggest that Myo10 plays a negative role in OC formation, likely by inhibiting Unc5b cell-surface targeting, and suppressing Netrin-1 promoted OC genesis. © 2019 American Society for Bone and Mineral Research.

[Role of electrocardiogram in predicting cardiac resynchronization therapy response]

OBJECTIVE

To explore the role of electrocardiogram(ECG)in predicting cardiac resynchronization therapy (CRT) response.

METHODS

This study retrospectively analyzed ECG of 92 CRT patients, who received CRT therapy from 2001 to 2013 in our center and were followed up for 6 months. The patients were divided into responder group (n=64) and non-responder group (n=28). The baseline and 6-month data including QRS width, heart rhythm and axis variation were analyzed. The definition of responder is left ventricular end systolic volume (LVESV) reduction ≥15% within 6 months after CRT. After CRT therapy, the ventricular activation was changed as left to right (frontal plane), posterior to anterior and axis changed in a clockwise direction. The change in more than two directions was defined as prominent axis change. Logistic analysis was performed to analyze the role of ECG in predicting CRT response.

RESULTS

(1) Baseline parameter comparison between the two groups: the proportion of female and LBBB is significantly higher (P<0.01; P=0.04), while the proportion of atrial fibrillation/flutter (Af/AF) is significantly lower (P<0.01) in responder group than in non-responder group. The pre-CRT average QRS duration is much wider in responder group than in non-responder group (P=0.01). (2) Comparison of follow-up with baseline results in two groups: NYHA heart function level, 6 minutes walking distance, QRS duration, LVEF, LVESV improved significantly (P<0.01) post-CRT in responder group. In non-responder group, the QRS duration and LVESV deteriorated significantly (P=0.02, P<0.01), while post-CRT NYHA heart function level improved significantly. In responder group, pre-CRT ECG axis of 53 patients (82.8%) pointed to left and 58 patients (90.6%) pointed to posterior; post-CRT ECG axis of 49 patients (76.6%) pointed to right and 30 patients (40.6%) pointed to anterior. In non-responder group, pre-CRT ECG axis of 25 patients (89.3%) pointed to left and 24 patients (85.7%) pointed to posterior; post-CRT ECG axis of 17 patients (60.7%) pointed to right and 12 patients (42.9%) pointed to anterior. Post-CRT, the proportion of ECG axis prominent change was significantly higher in responder than in non-responder group (62.5%(40/64) vs. 32.1%(9/28), P=0.007). (3)Predicting value: pre-CRT QRS width ≥140 ms (OR=4.97, 95% CI 1.53 to 16.13, P=0.008)and post-CRT prominent axis change (OR=5.1, 95% CI 1.67 to 15.5, P=0.004)were found to be independent predictors of CRT responders. Af/AF pre-CRT was associated with reduced CRT response (OR=0.25, 95% CI 0.08 to 0.80, P=0.02).

CONCLUSIONS

ECG may play a role in predicting CRT response. QRS width and Af/AF before CRT and ECG axis change post-CRT could be used to predict CRT response.

Iron Chelation Inhibits Osteoclastic Differentiation In Vitro and in Tg2576 Mouse Model of Alzheimer's Disease

Patients of Alzheimer's disease (AD) frequently have lower bone mineral density and higher rate of hip fracture. Tg2576, a well characterized AD animal model that ubiquitously express Swedish mutant amyloid precursor protein (APPswe), displays not only AD-relevant neuropathology, but also age-dependent bone deficits. However, the underlying mechanisms remain poorly understood. As APP is implicated as a regulator of iron export, and the metal chelation is considered as a potential therapeutic strategy for AD, we examined iron chelation's effect on the osteoporotic deficit in Tg2576 mice. Remarkably, in vivo treatment with iron chelator, clinoquinol (CQ), increased both trabecular and cortical bone-mass, selectively in Tg2576, but not wild type (WT) mice. Further in vitro studies showed that low concentrations of CQ as well as deferoxamine (DFO), another iron chelator, selectively inhibited osteoclast (OC) differentiation, without an obvious effect on osteoblast (OB) differentiation. Intriguingly, both CQ and DFO's inhibitory effect on OC was more potent in bone marrow macrophages (BMMs) from Tg2576 mice than that of wild type controls. The reduction of intracellular iron levels in BMMs by CQ was also more dramatic in APPswe-expressing BMMs. Taken together, these results demonstrate a potent inhibition on OC formation and activation in APPswe-expressing BMMs by iron chelation, and reveal a potential therapeutic value of CQ in treating AD-associated osteoporotic deficits.

Aurora-A is a determinant of tamoxifen sensitivity through phosphorylation of ERα in breast cancer

Despite the clinical success of tamoxifen, its resistance remains a major challenge in breast cancer. Here we show that Aurora-A determines tamoxifen sensitivity by regulation of oestrogen receptor (ER)α. Ectopic expression of Aurora-A decreases and depletion of Aurora-A enhances tamoxifen sensitivity in ERα-positive breast cancer. Elevated Aurora-A was significantly associated with the recurrence of ERα-positive tumours. Notably, Aurora-A inhibitor MLN8237, which is currently in clinical trial, synergizes with tamoxifen and overcomes tamoxifen resistance. Furthermore, Aurora-A interacts with and phosphorylates ERα on serine-167 and -305, leading to increase in ERα DNA-binding and transcriptional activity. Elevated levels of Aurora-A are significantly associated with disease-free survival in ERα-positive but not ERα-negative breast cancers. These data suggest that Aurora-A has a pivotal role in tamoxifen resistance and ERα is a bona fide substrate of Aurora-A. Thus, Aurora-A represents a prognostic marker in ERα-positive tumour and a critical therapeutic target in tamoxifen-resistant breast cancer, and Aurora-A inhibitor could be used as either an independent or concurrent agent in tamoxifen-resistant tumour.

Population pharmacokinetics of valnemulin in swine

This study was carried out in 121 pigs to develop a population pharmacokinetic (PPK) model by oral (p.o.) administration of valnemulin at a single dose of 10 mg/kg. Serum biochemistry parameters of each pig were determined prior to drug administration. Three to five blood samples were collected at random time points, but uniformly distributed in the absorption, distribution, and elimination phases of drug disposition. Plasma concentrations of valnemulin were determined by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The concentration-time data were fitted to PPK models using nonlinear mixed effect modeling (NONMEM) with G77 FORTRAN compiler. NONMEM runs were executed using Wings for NONMEM. Fixed effects of weight, age, sex as well as biochemistry parameters, which may influence the PK of valnemulin, were investigated. The drug concentration-time data were adequately described by a one-compartmental model with first-order absorption. A random effect model of valnemulin revealed a pattern of log-normal distribution, and it satisfactorily characterized the observed interindividual variability. The distribution of random residual errors, however, suggested an additive model for the initial phase (<12 h) followed by a combined model that consists of both proportional and additive features (≥ 12 h), so that the intra-individual variability could be sufficiently characterized. Covariate analysis indicated that body weight had a conspicuous effect on valnemulin clearance (CL/F). The featured population PK values of Ka , V/F and CL/F were 0.292/h, 63.0 L and 41.3 L/h, respectively.

Population pharmacokinetics of cefquinome in pigs

This study was performed in 145 pigs to develop a population pharmacokinetics (PPK) model by i.m. administration of cefquinome (CEQ) at the dose of 2 mg/kg in the neck muscle. Serum physiological and biochemical parameters for each pig were determined before administration. After administration, 2-4 samples were collected at random, with the sampling point evenly distributed in the three periods (<1 h, 1-4 h and >4 h). The plasma concentration of CEQ was determined by high performance liquid chromatography with UV detector. The pharmacostatistical analyses of concentration-time data, weight, age, gender, serum physiological and biochemical parameters were performed with nonlinear mixed effect modeling (NONMEM). A one-compartmental model with first-order absorption and elimination adequately described the data from the study group. The optimal random effect model of pharmacokinetics parameters was of log-normal distribution and the residual errors assumed a mixed-type model (proportional and additive) to best explain intra-individual variability. Covariate analysis showed that body weight is positively correlated with apparent volume of distribution (V/F) and body clearance (CL/F). The typical PPK parameters of Ka , CL, and V were 0.564/h, 5.15 L/h, and 1.36 L, respectively.

An evaluation of resident exposure to respirable particulate matter and health economic loss in Beijing during Beijing 2008 Olympic Games

Previous epidemiological studies showed that air pollutants, especially respirable particulate matter, including PM(10), could impose harmful effects on human health. The assessment of the effects of PM(10) on mortality and morbidity makes an important basis for enhancing pollution control efforts, and for protecting public health. In this study, we measured the levels of Beijing residents' exposure to PM(10) during three different time periods around the Beijing Olympic Games held in 2008, and calculated the economic cost associated with human health. A comparative analysis of human exposure to PM(10) and associated health economics was also made to see the difference between 2005 and 2008. GIS technology was employed to interpolate the distribution of population and PM(10) data collected by 27 stations at a scale of 1kmx1km. Study results show that Beijing's population is distributed in a highly inhomogeneous manner, with the majority of people dwelling in the city proper. During the Olympic Games, population-weighted PM(10) exposure came down by 46% and 19% respectively, compared with the pre-OG and the post-OG periods. Consequently, the economic cost associated with human health during the Games came down by 38% and 16% respectively, compared with the pre-OG and the post-OG periods. Comparative analysis shows that during the Olympic Games, both PM(10) and the economic cost associated with health as a proportion of GDP sat at the bottom of the 4-year statistics, indicating that in addition to favorable weather conditions, enhanced traffic and emission control policies and measures have produced a noticeable effect on PM(10) reduction.

RGMA and IL21R show association with experimental inflammation and multiple sclerosis

Rat chromosome 1 harbors overlapping quantitative trait loci (QTL) for cytokine production and experimental models of inflammatory diseases. We fine-dissected this region that regulated cytokine production, myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE), anti-MOG antibodies and pristane-induced arthritis (PIA) in advanced intercross lines (AILs). Analysis in the tenth and twelfth generation of AILs resolved the region in two narrow QTL, Eae30 and Eae31. Eae30 showed linkage to MOG-EAE, anti-MOG antibodies and levels of interleukin-6 (IL-6). Eae31 showed linkage to EAE, PIA, anti-MOG antibodies and levels of tumor necrosis factor (TNF) and IL-6. Confidence intervals defined a limited set of potential candidate genes, with the most interesting being RGMA, IL21R and IL4R. We tested the association with multiple sclerosis (MS) in a Nordic case-control material. A single nucleotide polymorphism in RGMA associated with MS in males (odds ratio (OR)=1.33). Polymorphisms of RGMA also correlated with changes in the expression of interferon-gamma (IFN-gamma) and TNF in cerebrospinal fluid of MS patients. In IL21R, there was one positively associated (OR=1.14) and two protective (OR=0.87 and 0.68) haplotypes. One of the protective haplotypes correlated to lower IFN-gamma expression in peripheral blood mononuclear cells of MS patients. We conclude that RGMA and IL21R and their pathways are crucial in MS pathogenesis and warrant further studies as potential biomarkers and therapeutic targets.

Wavefront reconstruction and three-dimensional shape measurement by two-step dc-term-suppressed phase-shifted intensities

A wavefront reconstruction and three-dimensional (3-D) shape measurement method by a two-step phase-shifting algorithm with arbitrary phase shift in (0,pi) is proposed. In this method, only two phase-shifted intensities, with the removal of the dc term by an averaging technique in spatial domain or low-pass filter operation in the frequency domain, are needed, and the other additional measurements are no longer required. The simulation for an irregular wavefront has shown the feasibility, and the optical experiment for a 3-D face mask in the case of a sinusoidal fringe projection system has illustrated the validity of the proposed method.

Definition of arthritis candidate risk genes by combining rat linkage-mapping results with human case-control association data

OBJECTIVE

To define genomic regions that link to rat arthritis and to determine the potential association with rheumatoid arthritis (RA) of the corresponding human genomic regions.

METHODS

Advanced intercross lines (AIL) between arthritis susceptible DA rats and arthritis resistant PVG.1AV1 rats were injected with differently arthritogenic oils to achieve an experimental situation with substantial phenotypic variation in the rat study population. Genotyping of microsatellite markers was performed over genomic regions with documented impact on arthritis, located on rat chromosomes 4, 10 and 12. Linkage between genotypes and phenotypes were determined by R/quantitative trait loci (QTL). Potential association with RA of single nucleotide polymorphisms (SNPs) in homologous human chromosome regions was evaluated from public Wellcome Trust Case Control Consortium (WTCCC) data derived from 2000 cases and 3000 controls.

RESULTS

A high frequency of arthritis (57%) was recorded in 422 rats injected with pristane. Maximum linkage to pristane-induced arthritis occurred less than 130 kb from the known genetic arthritis determinants Ncf1 and APLEC, demonstrating remarkable mapping precision. Five novel quantitative trait loci were mapped on rat chromosomes 4 and 10, with narrow confidence intervals. Some exerted sex-biased effects and some were linked to chronic arthritis. Human homologous genomic regions contain loci where multiple nearby SNPs associate nominally with RA (eg, at the genes encoding protein kinase Calpha and interleukin 17 receptor alpha).

CONCLUSIONS

High-resolution mapping in AIL populations defines limited sets of candidate risk genes, some of which appear also to associate with RA and thus may give clues to evolutionarily conserved pathways that lead to arthritis.

Extending gastric emptying scintigraphy from two to four hours detects more patients with gastroparesis

Gastric emptying scintigraphy (GES) is usually performed for up to 2 hr to measure the gastric emptying (GE) of solids. Symptomatic patients, however, may have borderline results at 2 hr, making it difficult to determine whether a gastric motor disorder is present. The aim of this study was to assess whether extending GES to 4 hr is useful in evaluating patients for gastroparesis and to correlate the results of GES with patient symptoms. We studied 129 patients undergoing GES at Temple University Hospital between July 1998 and March 1999. Solid-phase GE was measured at 0, 0.5, 1, 2, 3, and 4 hr after ingestion of a 99mTc sulfur colloid-labeled egg meal. Dyspeptic symptoms of upper abdominal discomfort, early satiety, postprandial abdominal bloating, nausea, vomiting, and anorexia were graded as none, mild, moderate and severe (0, 1, 2 and 3, respectively) with the sum representing a total symptom score. Of 129 patients, 86 had normal GE at 2 hr; 26 of the 86 normal scans at 2 hr were delayed at 3 hr. Six of the 60 scans normal at 2 and 3 hr were delayed at 4 hr. Of 43 patients with delayed GE at 2 hr, 39 were delayed at 3 hr and 35 were delayed at 4 hr. Overall, the percentage of patients with delayed GE increased from 33% at 2 hr only to 58% using the results of the 2-, 3-, and 4-hr scans (P < 0.05). There was a significantly greater symptom score in patients with delayed GE compared to patients with normal GE (8.4 +/- 0.5 vs 7.1 +/- 0.5; P < 0.05). Conclusion, prolonging GES after ingestion of a 99mTc-labeled egg meal from 2 to 4 hr increased the number of symptomatic patients found to have delayed GE. These results suggest that GES should be performed for up to 4 hrs when the 2-hr result is normal.

[Studies on synthetic peptide. XX: the antigenicity and linear epitope map of synthetic peptide hepatitis C virus]

Hepatitis C virus (HCV), the major causative agent of post transfusion non-A, non-B hepatitis (NANB), had been cloned and expressed. According to the protein sequence of HCV-BK and its epitope profiles which combined the hydrophilicity, accessibility, flexibility, antigenicity, charge distribution and HPLC reserve coefficient of protein using the "Goldkey" computer program, we designed and synthesized the following peptides: P1(475-495), P3(449-468), P4(658-663), P5(645-663), P6(484-489), P7(475-489), P15(655-662), P16(230-237), P17(225-237), P18(1220-1240), P19(1694-1735), P24(1230-1240), P25(1482-1493), P26(384-389), P27(2355-2389). The results of ELISA showed that P6(60% positive results) and P19(63% positive results) testing with PT-HC of Gu An, Hebei province were the major antigens in NS1 and in NS4 region, respectively.

Development of potent non-estrogenic estrone sulfatase inhibitors

Estrogen levels in breast tumors of post-menopausal women are as much as 10 times higher than estrogen levels in plasma, presumably due to in situ formation of estrogen. The major source of estrogen in breast cancer cells may be conversion of estrone sulfate to estrone by the enzyme estrone sulfatase. Thus, inhibitors of estrone sulfatase have potential for the treatment of estrogen-dependent breast cancers. Several steroidal agents have been developed that are potent estrone sulfatase inhibitors, most notably estrone-3-O-sulfamate. These compounds may have undesired actions, especially estrogenicity. Recently, non-steroidal estrone sulfatase inhibitors have been designed that avoid the problems associated with an active steroid nucleus; however, these have not achieved the potency of estrone-3-O sulfamate. We have designed and synthesized a series of compounds, 17 beta-(N-alkylcarbamoyl)-estra-1,3,5(10)-trien-3-O-sulfamates (6a-d) and 17 beta-(N-alkanoyl)-estra-1,3,5(10)-trien-3-O-sulfamates (11a-d) that combine the structural features of the steroidal estrone sulfatase inhibitors with a membrane insertion region that should increase the affinity for the sulfatase enzyme and decrease the estrogenicity of the steroid. We tested the compounds for estrone sulfatase inhibition by measuring estrone sulfatase activity in intact cultures of human breast cancer cells (MDA-MB-231). We tested for estrogenicity by measuring growth of estrogen-dependent MCF-7 human breast cancer cells. All of the test compounds (10 nM) substantially inhibited estrogen sulfatase activity of intact MDA-MB-231 cells. Dose-response analysis indicated an IC50 of approximately 0.5 nM for two of the compounds (6a and 11a). In the test for estrogenicity, estrone and estrone-3-O-sulfamate significantly stimulated MCF-7 cell growth. In contrast, neither the 17 beta-(N-alkylcarbamoyl)-estra-1,3,5,(10)-trien-3-O-sulfamates++ + nor the 17 beta-(N)-alkanoyl)-estra-1,3,5,(10)-trien-3-O-sulfamates stimulated growth of MCF-7 cells at a concentration of 1 microM, indicating that they are not estrogenic at levels 2000 times greater than their IC50 for estrone sulfatase. Our data indicate the utility of the new compounds for inhibition of breast cancer cell estrone sulfatase activity. Further, our data support the concept that estrone sulfatase inhibitors may be useful as therapeutic agents for estrogen-dependent breast cancers.

Direct measurement of nitric oxide release from vascular endothelial cells

A nitric oxide (NO)-selective electrode was used to directly measure NO release from isolated rat aortic endothelium and cultured rat aortic endothelial cells (RAECs). Basal release of NO was significantly attenuated by a NO synthase inhibitor NG-nitro-L-arginine methyl ester (1 mM) to 42 +/- 14 pmol/1 x 10(5) cells (P < 0.01). The basal release of NO was also significantly inhibited by a calmodulin antagonist W-7 at 15 microM (P < 0.01). L-Arginine (1 mM), significantly stimulated NO release (P < 0.05 vs. control basal release). Stimulation of cultured RAECs with two endothelium-dependent vasodilators, acetylcholine (100 nM) and A-23187 (1 microM), significantly increased NO release [574 +/- 112 pmol/1 x 10(5) cells (n = 5) and 658 +/- 119 pmol/1 x 10(5) cells (n = 5) in acetylcholine- and A-23187-stimulated RAECs, respectively]. Basal release of NO was also detectable in isolated rat aortic rings with intact endothelium. NO release was significantly attenuated by NG-nitro-L-arginine methyl ester and augmented by human superoxide dismutase. These data indicate the physiological usefulness of the amperometric measurement of NO employing a NO-specific electrode in biological systems.

[Studies on peptide. XIX: Hepatitis C virus (HCV) immune selection]

HCV has characteristics of rapid variability. The amino terminus of E2/NS1 of HCV (amino acids sequence 384-414), which is hypervariable with respect to both nucleotide and amino acid sequence, has been termed the E2 HV domain or HVR1. The E2 HV domain appears to be a rapidly evolving region of the HCV genomes which may contain linear neutralizing epitopes and the E2 HV are under immune selection. For further studies of the immunogenicity on E2 HV of HCV, we selected three peptide fragments from the full length of E2 HV region sequence and synthesized them with SPPS method. The amino acid sequences are shown as following: P2: VDGDTHVTGGAQAKTTNR (381-398); P9: STHVTGAVQGHSIRGTTSLFTSGPAQKIQ (384-412); P10: RTYTSGGTAGHTTSGITSLFSPGASQKIQ (384-412). From the results of ELISA and anti-peptide Abs of rabbit sera, we conclude that there are anti-E2 HV Abs in immune host but they could not neutralize HCV, so these Abs were not reactive with all E2 HV epitopes that resulted in immune selection of escape mutants; the anti-E2 HV Abs, probably from the same genotype, contained some common structure in which E2 HV epitopes react with other anti-E2 HV Abs at 30%: the C-terminus of E2 HV region (398-412) caused the immune response to rabbits.

Nitric oxide protects against leukocyte-endothelium interactions in the early stages of hypercholesterolemia

We studied the effects of CAS1609, a nitric oxide donor, on leukocyte-endothelial interactions during the early stages of hypercholesterolemia in rat mesenteric microcirculation. Rats were randomly divided into four groups: (a) rats fed control diet, (b) rats fed control diet while receiving CAS1609, (c) rats fed a high-cholesterol (HC) diet and given C93-4845 (an inactive control compound), and (d) rats fed an HC diet and given CAS1609. Both HC groups developed significantly elevated plasma cholesterol levels compared with rats fed the control diet. Intravital microscopy of mesenteric venules revealed a significant increase in leukocyte rolling and adherence in the untreated HC rats compared with control rats (P < .01). This was significantly attenuated in the HC rats given CAS1609. The HC rats given C93-4845 also developed aortic endothelial dysfunction (ie, impaired relaxation to acetylcholine or ADP) that was significantly prevented by CAS1609 infusion (P < .02). Immunohistochemical staining of ileum demonstrated significantly enhanced localization of P-selectin and intercellular adhesion molecule-1 (ICAM-1) on venular endothelium in the untreated HC rats compared with control rats (P < .01). However, P-selectin and ICAM-1 expression were significantly attenuated in HC rats given CAS1609 (P < .05 and P < .01, respectively). Thus, hypercholesterolemia induces microvascular dysfunction characterized by loss of endothelium-derived nitric oxide, increased rolling and adherence of leukocytes, and increased expression of P-selectin and ICAM-1. Infusion of CAS1609 significantly attenuated these changes due to hypercholesterolemia. Our data suggest that nitric oxide plays a significant role in the prevention of the early endothelial dysfunction observed in hypercholesterolemia.

Cardioprotective effects of selective inhibition of the two complement activation pathways in myocardial ischemia and reperfusion injury

The complement (C) system-mediated neutrophil activation, adhesion to the coronary endothelium and accumulation into cardiac tissue are key steps in the pathogenesis of myocardial ischemia-reperfusion (MI/R) injury. We examined the differential role of the classical and the alternative complement pathway in MI/R injury in vivo. Rats were subjected to 20 min of myocardial ischemia followed by 24 h of reperfusion. Either a classical pathway inhibitor [C1 esterase inhibitor (C1-INH) (15 mg/kg)] or an alternative pathway inhibitor soluble complement receptor 1 (sCR1)[des-LHR-A](15 mg/kg) or their vehicle were administered intravenously 1 min prior to reperfusion, and myocardial necrosis (creatine kinase loss) and neutrophil accumulation, cardiac myeloperoxidase activity, were examined. C1-INH significantly attenuated cardiac creatine kinase loss compared to MI/R rats given only vehicle (p < 0.05) 24 h after reperfusion. An alternative pathway inhibitor, sCR1 [des-LHR-A] attenuated myocardial injury to a lesser extent, although it was not significantly different from the value for C1-INH or vehicle. Besides cardiac myeloperoxidase activity, the ischemic cardiac tissue was significantly attenuated by both C1-INH and sCR1[desLHR-A] (p < 0.05 vs. vehicle). Both the classical and alternative pathways may contribute to MI/R injury via a neutrophil-dependent mechanism in vivo. Selective inhibition of the classical pathway of complement activation seems to be slightly more effective in limiting necrotic MI/R injury than the selective alternative pathway inhibition in this 24 h model of reperfusion injury, but equal doses of each inhibitor attenuated neutrophil accumulation.

Mechanisms of vascular preservation by a novel NO donor following rat carotid artery intimal injury

We studied the effects of a novel organic nitric oxide (NO) donor, 4-hydroxymethyl-furazan-3-carboxylic acid-2-oxide (CAS-1609), in a rat carotid artery intimal injury model. The NO donor, CAS-1609, or its non-NO-donating control compound, 4-hydroxymethyl-furazan-3-carboxylic acid (C-93-4845), was infused intravenously at 30 micrograms/day. Seven days after injury, carotid artery rings contracted only 56 +/- 6 mg to NG-nitro-L-arginine methyl ester in C-93-4845-treated rats, compared with 120 +/- 17 mg in CAS-1609-treated rats (P < 0.02), indicating a preservation of endogenous NO release. Improved responses to the endothelium-dependent dilator, acetylcholine, also occurred in injured arteries treated with CAS-1609. Morphometric analysis of injured carotid arteries given the inactive compound showed marked intimal thickening with an intimal-to-medial ratio (I/M) of 0.76 +/- 0.02, compared with a significantly lower I/M of 0.32 +/- 0.04 (P < 0.01) in injured carotid arteries given CAS-1609. Additionally, CAS-1609 was found to have a concentration-dependent stimulatory effect on cultured rat aortic endothelial cell proliferation (P < 0.01) but and inhibitory effect on platelet-derived growth factor-BB (10 ng/ml)-stimulated rat aortic smooth muscle cell proliferation (P < 0.01). This is the first study to demonstrate that NO plays a dual role in vascular cell proliferation, stimulating endothelial cells but inhibiting smooth muscle cell proliferation. This dual effect of NO on cell proliferation is associated with an in vivo reduction in neointimal thickening and an acceleration of endothelial recovery determined by both anatomic and functional methods.

Cardioprotection by a novel recombinant serine protease inhibitor in myocardial ischemia and reperfusion injury

Polymorphonuclear neutrophils (PMN) play an important role in myocardial ischemia/reperfusion (MI/R) injury; however, the role of neutrophilic proteases is less understood. The effects of a novel serine protease inhibitor (serpin), LEX032, were investigated in a murine model of MI (20 min) and R (24 hr) injury in vivo. LEX032 is a recombinant human alpha 1-antichymotrypsin in which six amino acid residues were replaced around the active center with those of alpha-1 protease inhibitor. LEX032 has the ability to inhibit both neutrophil elastase and cathepsin G, two major neutral serine proteases in neutrophils, as well as superoxide generation. LEX032 (25 or 50 mg/kg) administered i.v. 1 min before reperfusion significantly attenuated myocardial necrotic injury evaluated by cardiac creatine kinase loss compared to MI/R rats receiving only vehicle (P < .001). Moreover, cardiac myeloperoxidase activity, an index of PMN accumulation, in the ischemic myocardium was significantly attenuated by LEX032 as compared with rats receiving vehicle (P < .001). LEX032 also moderately attenuated leukotriene B4-stimulated PMN adherence to rat superior mesenteric artery endothelium and markedly diminished superoxide radical release from LTB4-stimulated PMN in vitro. In a glycogen-induced rat peritonitis model, LEX032 (50 mg/kg) significantly attenuated PMN transmigration into the peritoneal cavity in vivo. In conclusion, the recombinant serine protease inhibitor, LEX032, appears to be an effective agent for attenuating MI/R injury by inhibiting neutrophil-accumulation into the ischemic-reperfused myocardium and by inactivating cytotoxic metabolites (proteases and superoxide radical) released from neutrophils.

Sialyl Lewisx-containing oligosaccharide exerts beneficial effects in murine traumatic shock

We investigated the effects of a soluble sialyl Lewisx-containing oligosaccharide (SLex-OS) in a rat model of traumatic shock. Pentobarbital-anesthetized rats subjected to Noble-Collip drum trauma developed a shock state characterized by marked hypotension, a survival time of 85 +/- 15 min, significant increases in ileal myeloperoxidase (P < 0.01), and plasma free amino-nitrogen activities (P < 0.01). Treatment with SLex-OS (10 mg/kg) 10 min posttrauma prolonged survival time to 198 +/- 29 min (P < 0.01), significantly attenuated ileal myeloperoxidase activity (P < 0.01), and diminished the accumulation of plasma free amino-nitrogen (P < 0.01), drug vs. vehicle, respectively. Furthermore, endothelium-dependent relaxation to acetylcholine in superior mesenteric artery rings isolated from SLex-OS-treated shock rats was significantly preserved (70 +/- 6 vs. 40 +/- 5% relaxation). No beneficial effects were observed using a nonfucosylated control oligosaccharide. Moreover, addition of SLex-OS significantly inhibited unstimulated human polymorphonuclear neutrophil (PMN) adherence in vitro to trauma-activated superior mesenteric artery endothelium ex vivo (P < 0.001). Our results indicate that SLex-OS exerts beneficial effects in traumatic shock states by blocking selectin-mediated leukocyte-endothelium interaction, thus improving survival, attenuating intestinal PMN accumulation, and diminishing shock-induced tissue injury.

Beneficial effect of SPM-5185, a cysteine-containing nitric oxide donor, in rat carotid artery intimal injury

We studied the effects of an organic nitric oxide (NO) donor SPM-5185 in a rat carotid artery intimal injury model. Seven days after injury, the two end segments of the injured carotid arteries were studied for endothelial release of NO, and the middle segments were used for histological measurement of the intimal-to-medial (I/M) ratio and scanning electron microscopy of the luminal surface. The NO donor SPM-5185 or its non-NO-donating control compound SPM-5267 were infused intravenously at 30 micrograms/d. Full vasorelaxant responses of rat carotid arterial rings were obtained with the endothelium-dependent vasodilators acetylcholine (ACh), A23187, and the endothelium-independent vasodilator acidified NaNO2 in sham-operated control rings. Impaired relaxation occurred with 10 mumol/L ACh and 1 mumol/L A23187 in injured rings but not in rings infused with SPM-5185 for 7 days. Relaxation to 100 mumol/L acidified NaNO2 was not significantly different among any of the groups, indicating a normal vascular smooth muscle response after intimal injury. Morphometric analysis of injured carotid arteries given vehicle and SPM-5267 showed marked intimal thickening with an average I/M ratio of 0.78 +/- 0.03 and 0.74 +/- 0.05, respectively. SPM-5185 markedly attenuated intimal thickening, resulting in an I/M ratio of 0.13 +/- 0.03 (P < .01 from vehicle), representing an approximately 82% inhibition of intimal thickening. SPM-5185 infusion resulted in accelerated regeneration of endothelial cells on the intimal surface at 7 days.(ABSTRACT TRUNCATED AT 250 WORDS)

Protective effects of a monoclonal antibody against lipid A in endotoxic shock

Bacterial lipopolysaccharide given intravenously at 30 mg/kg to anesthetized rats results in rapid systemic hypotension and hypovolemia, elaboration of cytokines, increased proteolysis and vascular endothelial dysfunction. When a monoclonal antibody SdJ5-1.17.15 (SdJ5) directed against the lipid A moiety of lipopolysaccharide was administered at (1.25 or 5.0 mg/kg) 5 min prior to the endotoxin, significant protection was afforded to rats. This protection was manifested by a significant reduction in the early hypotension, as well as attenuation of hypovolemia and proteolysis. To evaluate endothelial function, superior mesenteric artery rings were isolated from endotoxemic rats 4 h after endotoxic challenge. Lipopolysaccharide (LPS) significantly reduced superior mesenteric artery vasorelaxation to acetylcholine and A23187, two endothelium-dependent vasodilators, but not to NaNO2, an endothelium-independent vasodilator. SdJ5 significantly preserved vasorelaxation responses to both acetylcholine and A23187, indicating a marked degree of endothelial preservation by this anti-lipid A monoclonal antibody. The protection was dose-dependent since 0.3 mg/kg of SdJ5 did not provide significant protection in any variable measured. Moreover, there was no significant difference between the 1.25 mg/kg and 5.0 mg/kg dose of SdJ5. Furthermore, plasma concentrations of TNF-alpha, a cytokine involved in mediating many of the effects associated with endotoxemia, was significantly reduced in SdJ5-treated animals. Thus, SdJ5 appears to be capable of counteracting many of the in vivo sequelae of endotoxemia in rats.

Endothelial preserving actions of a nitric oxide donor in carotid arterial intimal injury

We examined the actions of a nitric oxide donor, CAS754, in a rat model of carotid artery intimal injury. Seven days following injury, the injured carotid arteries were studied for endothelial release of nitric oxide (NO) and for histological measurement of the intimal/medial (I/M) ratio. Basal release of NO was assessed by NG-nitro-L-arginine methyl ester (L-NAME)-induced vasocontraction. L-NAME contracted injured rat carotid artery rings about 27% of that obtained in control rats (p < 0.01). However, CAS754 given at 30 mcg/day i.v. resulted in a L-NAME contraction of twice that of vehicle-treated rats (p < 0.01). A control compound lacking the NO moiety (C-3934) yielded a contraction to L-NAME comparable to untreated injured rats. We also tested the ability of rat carotid artery rings to relax to the endothelium-dependent vasodilators, acetylcholine and A23187. ACh (10 mcM) relaxed carotid artery rings only about 20% of control values in vehicle-treated and in C-3934-treated rats, compared with a vasorelaxation of over 80% of control in CAS754-treated rats (p < 0.01). Relaxation to acidified NaNO2 (100 mcM) was not significantly different among any of the groups of carotid arteries, indicating normal vascular smooth muscle responses following intimal injury. Morphometric assessment of carotid arteries isolated from injured rats given either vehicle or C-3934 showed marked intimal thickening with an average intimal/medial (I/M) ratio of 0.79 +/- 0.05 and 0.73 +/- 0.06, respectively, compared with 0.10 +/- 0.02 in non-injured arteries.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary artery endothelial dysfunction following ischemia and reperfusion of the rabbit lung

We studied endothelial dysfunction of the rabbit pulmonary artery following in vivo ischemia and reperfusion of the lung, and also investigated the mechanisms of endothelium-dependent relaxation in these arteries. Intrapulmonary arteries were isolated from rabbits subjected to ischemia and reperfusion of one lung. Percent relaxation values of sham-operated (i.e. nonischemic) pulmonary arteries to endothelium-dependent vasodilators acetylcholine (ACh) and A23187 were 72 +/- 4 and 65 +/- 4%, respectively, while relaxation to the endothelium-independent dilator NaNO2 was 97 +/- 1%. The relaxation of control artery rings to ACh and A23187 were significantly decreased to 2 +/- 1 and 5 +/- 4%, respectively, following addition of N omega-nitro-L-arginine methyl ester, while relaxation following treatment with indomethacin or glybenclamide remained normal. Relaxation to NaNO2 was not altered by pretreatment with any of the above compounds. Thus, pulmonary artery relaxation to the endothelium-dependent dilators ACh and A23187 appears to be mediated by the release of EDRF. Endothelium-dependent relaxation of pulmonary arteries from lungs exposed to 90 min of ischemia and 30 min of reperfusion remained essentially normal, while 90 min of ischemia followed by 60 min of reperfusion resulted in a significant decrease in endothelium-dependent relaxation to A23187 to 37 +/- 7% (p < 0.05), whereas the response to ACh was reduced only to 57 +/- 3% (not significant). 90 min of ischemia followed by 90 min of reperfusion resulted in significant attenuation of endothelium-dependent relaxation to both ACh (36 +/- 4%) and A23187 (33 +/- 7%).(ABSTRACT TRUNCATED AT 250 WORDS)

Protective actions of a leukotriene B4 antagonist in splanchnic ischemia and reperfusion in rats

Pentobarbital-anesthetized rats were subjected to occlusion of both the celiac and superior mesenteric arteries for 90 min followed by reperfusion for 2 h. All seven rats given only the vehicle died within 2 h of reperfusion, whereas rats treated with LY-255283 (3 or 10 mg/kg iv), a leukotriene B4 (LTB4) receptor antagonist given 10 min before reperfusion, exhibited significantly higher survival rates of 57% (4 out of 7) and 75% (6 out of 8), respectively, 2 h after reperfusion. Rats given 1 mg/kg of LY-255283 showed no significant improvement in survival. Splanchnic artery occlusion (SAO)-shock rats treated with LY-255283 (3 or 10 mg/kg) exhibited significantly attenuated accumulation of plasma free amino-nitrogenous compounds and of a myocardial depressant factor. Treatment with LY-255283 (10 mg/kg) markedly (P less than 0.01) ameliorated the deficits of endothelium-dependent relaxation of isolated superior mesenteric artery (SMA) rings in untreated SAO-shock rats. LY-255283 at 10 mg/kg significantly attenuated the increased myeloperoxidase activity in the intestinal tissue of SAO-shock rats. Moreover, LY-189444, a closely related compound having no LTB4 antagonist activity, did not protect rats in SAO shock, whereas a lipoxygenase inhibitor confirmed protection in SAO shock. These results suggest that LTB4 plays a pivotal role in endothelial dysfunction occurring in SAO-shock rats by chemoattraction and activation of neutrophils on the surface of vascular endothelial cells. Moreover, LY-255283 but not LY-189444 inhibited the adherence of rat neutrophils to isolated SMA endothelium.(ABSTRACT TRUNCATED AT 250 WORDS)

Beneficial effects of transforming growth factor-beta and tissue plasminogen activator in splanchnic artery occlusion and reperfusion in cats

We studied the effects of transforming growth factor-beta (TGF-beta), tissue plasminogen activator (tPA), and their combination in cats subjected to splanchnic artery occlusion (SAO) with reperfusion. Untreated anesthetized cats subjected to total occlusion of the celiac, superior, and inferior mesenteric arteries for 120 min, followed by reperfusion, uniformly died within 120 min after reperfusion. The mean survival time was 75 +/- 8 min. Plasma amino-nitrogen concentrations and cathepsin D and myocardial depressant factor (MDF) activities were markedly elevated following reperfusion. Superior mesenteric artery (SMA) rings isolated from cats subjected to SAO with reperfusion exhibited a significant loss of vasorelaxation to the endothelium-dependent dilators acetylcholine and A-23187. Administration of tPA (1 mg/kg) intravenously just before reperfusion did not prolong survival time (81 +/- 10 min) nor did it influence any biochemical or cardiovascular responses following reperfusion or ameliorate the depressed endothelium-dependent relaxation of SMA rings. In contrast, TGF-beta (50 micrograms/cat) ameliorated the SAO postreperfusion state in terms of survival rate and plasma MDF activity, and protected against depressed endothelium-dependent relaxation of SMA rings. TGF-beta alone slightly increased the survival time to 102 +/- 11 min. However, combined treatment with tPA (1 mg/kg) and TGF-beta (50 micrograms/cat) preserved endothelium-dependent relaxation and prevented increases in plasma amino-nitrogen more prominently than TGF-beta given alone and significantly increased the survival time to 118 +/- 3 min (p less than 0.01). These results indicate that TGF-beta exerts beneficial effects in SAO followed by reperfusion in cats, and tPA has an augmenting action on some of the beneficial effects of TGF-beta. These findings suggest that TGF-beta alone or in combination with tPA may be potentially useful therapeutic regimens in splanchnic ischemia shock by preserving splanchnic parenchymal and endothelial cells.

Mortality trend in a rapidly developing economy in Taiwan. Part II: Life expectancy and "potential years of life lost"

Taiwan has made remarkable economic progress in the last 30 years. The life expectancy of its population improved steadily during this period. A male child born in 1983 could look forward to 70.4 years of life and a female child to 75.3 years, gains of 17.5 years and 19.0 years, respectively, since 1950. The potential gains in life expectancy of the Taiwan population are also examined if the five leading causes of death are reduced or eliminated. In addition, this paper discusses the concept of potential productive years of life lost (PYLL), examines the leading causes of premature death and shows how this measure can be used to target prevention programs and health care planning.