Malonyl CoA Decarboxylase Inhibition Improves Cardiac Function Post-Myocardial Infarction

•

MCD inhibition decreases fatty acid oxidation via increasing malonyl coenzyme A levels to prevent fatty acid uptake into mitochondria in the failing hearts induced by coronary artery ligation.

•

Downregulating fatty acid oxidation by MCD inhibition occurrs in conjuction with a decrease in glycolysis and in proton production while an increase in triacylglycerol biosynthesis.

•

MCD inhibition enhances antioxidative capacity through increasing mitochondrial superoxide dismutase activity via reducing its acetylation.

Alterations in cardiac energy metabolism after a myocardial infarction contribute to the severity of heart failure (HF). Although fatty acid oxidation can be impaired in HF, it is unclear if stimulating fatty acid oxidation is a desirable approach to treat HF. Both immediate and chronic malonyl coenzyme A decarboxylase inhibition, which decreases fatty acid oxidation, improved cardiac function through enhancing cardiac efficiency in a post–myocardial infarction rat that underwent permanent left anterior descending coronary artery ligation. The beneficial effects of MCD inhibition were attributed to a decrease in proton production due to an improved coupling between glycolysis and glucose oxidation.

[Analysis of Clavien-Dindo classification and its prognosis factors of complications after laparoscopic right hemicolectomy]

Objective: To analyze the Clavien-Dindo classification of complications after right hemicolectomy and to explore the prognosis factors for postoperative complications. Methods: The retrospective case-control study was adopted. The clinical data of 176 patients who underwent right hemicolectomy at Department of General Surgery, Peking Union Medical College Hospital from October 2016 to February 2018 were collected. There were 95 male and 81 female patients with age of (62.4±12.7) years. The Clavien-Dindo classification was used for postoperative complications. Univariate and multivariate analysis were used to analyze the independent prognosis factors of complications after right colon resection. Results: Of the 176 patients, 2 patients had intraoperative complications (1.1%) and 39 patients had postoperative complications (22.2%), of which 10 cases had more than two complications, with a total of 53 complications. The proportions of Clavien-Dindo grade Ⅰ, Ⅱ, Ⅲ and Ⅳ complications were 41.5% (22/53), 49.1% (26/53), 7.5% (4/53), and 1.9%(1/53). Postoperative complications were associated with age, smoking history of the last 1 year, combined organ resection, lymph node dissection, intracorporeal anastomosis, and preoperative blood AST and Ca levels (all P<0.05). The results of multivariate analysis showed that intracorporeal anastomosis (OR=5.62, 95% CI: 2.46 to 12.85, P=0.00), preoperative blood AST (OR=-0.009, 95% CI: -0.018 to 0.000, P=0.04) and Ca (OR=0.51, 95% CI: 0.08 to 0.95, P=0.02) levels were independent prognosis factors affecting complications after right hemicolectomy. Conclusions: Complications of right hemicolectomy were mainly Clavien-Dindo grade Ⅰ and Ⅱ. Laparoscopic intracorporeal anastomosis should be carefully chosen, which may increase postoperative complications.

[Oncological outcomes analysis of colorectal cancer with unfavorable histological features]

Objective: To explore the effect of unfavorable histological features on the clinical outcomes of patients receiving radical resection of colorectal cancer. Methods: A retrospective analysis of patients with colorectal cancer who received radical surgery between January 2013 and December 2015 at Department of General Surgery, Peking Union Medical College Hospital was performed. The impact of unfavorable histological features on the oncological outcomes of patients with lymph node-negative colorectal cancer were analyzed.A total of 167 patients were enrolled, including 98 males and 69 females with age of (63.6±11.6) years. Observation indicators included age, T stage, lymphovascular invasion, perineural invasion, tumor deposits, number of lymph node dissection, degree of differentiation, tissue type, and circumferential margin. Univariate analysis was performed with χ(2) test and multivariate analysis was performed with Cox regression model. Results: Univariate analysis showed that positive circumferential margins (CRM), tumor deposits and age were associated with disease free survival (DFS) rate; positive CRM, age, tumor deposits, and lymph nodes dissection less than 12 were significantly associated with overall survival (OS) rate (all P<0.05). Multivariate analysis showed that over 70 years of age (HR=1.053, 95% CI: 1.013 to 1.095, P=0.009), poorly differentiated adenocarcinoma (HR=7.572, 95%CI: 1.815 to 31.587, P=0.005), tumor deposits (HR=4.711, 95% CI: 1.809 to 12.264, P=0.002), mucinous adenocarcinoma (HR=3.063, 95% CI: 1.003 to 9.354, P=0.049), lymphovascular invasion (HR=2.885, 95% CI: 1.062 to 7.832, P=0.038), and nerve infiltration (HR=6.610, 95% CI: 1.037 to 42.122, P=0.046) were adverse prognostic factors of DFS rate; poorly differentiated adenocarcinoma (HR=12.200, 95% CI: 1.985 to 74.972, P=0.007), tumor nodules (HR=5.379, 95% CI: 1.636 to 17.685, P=0.006), over 70 years of age (HR=1.062, 95% CI: 1.013 to 1.114, P=0.013), and perineural invasion (HR=8.043, 95% CI: 1.026 to 63.055, P=0.047) were adverse prognostic factors of OS rate. There was no significant difference in the 3-year DFS rate and 3-year OS rate between T1-2 group and T3-4 group (P>0.05). Conclusion: Over 70 years of age, poorly differentiated adenocarcinoma, mucinous adenocarcinoma, tumor nodules, lymphovascular invasion, and perineural invasion are independent adverse prognostic factors of lymph node-negative colorectal cancer.

[A case of human infection with highly pathogenic avian influenza A (H7N9) virus through poultry processing without protection measure]

Objective: To investigate the infection pattern and etiological characteristics of a case of human infection with highly pathogenic avian influenza A (H7N9) virus and provide evidence for the prevention and control of human infection with highly pathogenic avian influenza virus. Methods: Epidemiological investigation was conducted to explore the case's exposure history, infection route and disease progression. Samples collected from the patient, environments and poultry were tested by using real time reverse transcriptase-polymerase chain reaction (RT-PCR). Virus isolation, genome sequencing and phylogenetic analysis were conducted for positive samples. Results: The case had no live poultry contact history, but had a history of pulled chicken processing without taking protection measure in an unventilated kitchen before the onset. Samples collected from the patient's lower respiratory tract, the remaining frozen chicken meat and the live poultry market were all influenza A (H7N9) virus positive. The isolated viruses from these positive samples were highly homogenous. An insertion which lead to the addition of multiple basic amino acid residues (PEVPKRKRTAR/GL) was found at the HA cleavage site, suggesting that this virus might be highly pathogenic. Conclusions: Live poultry processing without protection measure is an important infection mode of "poultry to human" transmission of avian influenza viruses. Due to the limitation of protection measures in live poultry markets in Guangzhou, it is necessary to promote the standardized large scale poultry farming, the complete restriction of live poultry sales and centralized poultry slaughtering as well as ice fresh sale.

[Willingness and influencing factors related to "centralized slaughtering, fresh poultry listing and marketing" strategy among the household chefs in Guangzhou]

Objective: To study the willingness and influence factors related to "centralized slaughtering, fresh poultry listing and marketing" strategy, among the household chefs, and provide reference for government to adjust and optimize the strategy on avian influenza prevention. Methods: According to the geographical characteristics and regional functions, 6 'monitoring stations' were selected from 12 residential districts of Guangzhou, respectively. Another 21 meat markets which selling live poultry, were selected in each station and 5 household chefs of each market were invited to attend a face to face interview. Basic information, personal cognitive, willingness and influencing factors to the policy were under study. Univariate and multivariate logistic regression methods were used. Results: A total of 664 household chefs underwent the survey and results showed that the rate of support to the "centralized slaughtering, fresh poultry listing and marketing" strategy was 44.6% (296/664). Results from the multi-factor logistic regression showed that those household chefs who were males (OR=1.618, 95% CI: 1.156-2.264, P=0.005), having received higher education (OR=1.814, 95% CI: 1.296-2.539, P=0.001), or believing that the existence of live poultry stalls was related to the transmission of avian influenza (OR=1.918, 95% CI: 1.341-2.743, P<0.001) were factors at higher risk. These household chefs also intended to avoid the use of live poultry stalls (OR=1.666, 95%CI: 1.203-2.309, P=0.002) and accept the "centralized slaughtering, fresh poultry listing and marketing" strategy. Conclusion: Detailed study on this subject and, setting up pilot project in some areas as well as prioritizing the education programs for household chefs seemed helpful to the implementation of the 'freezing-fresh poultry' policy.

[Clinical application and prognostic analysis of interventional treatment for cesarean scar pregnancy]

OBJECTIVE

To analyze the clinical value and prognosis of cesarean scar pregnancy (CSP) treated by uterine artery embolization (UAE).

METHODS

In the study, 492 cases of patients in Nanjing Maternal and Child Health Care Hospital Affiliated to Nanjing Medical University diagnosed as CSP between January 2011 and December 2014 were chosen, of which 283 were of high-risk group and 209 of low-risk group. According to whether to take UAE, the high-risk group was subdivided into high-risk UAE group(UAE+laparoscopic group), 167 cases, and high-risk non UAE group (chemotherapy+laparoscopic group), 116 cases, while the low-risk group was subdivided into low-risk UAE group (UAE+curettage group), 113 cases, and low-risk non UAE group(chemotherapy+curettage group), 96 cases. The differences of the intraoperative bleeding, length of stay, blood beta human chorionic gonadotropin (β-HCG) dropped to normal time, menstruation recovery time and the hospitalization expenses were compared. And multivariate regression analysis was used to predict the recurrence risk of CSP.

RESULTS

The high-risk UAE group was better than the high-risk non UAE group in comparison of intraoperative bleeding [(36.5±14.8) mL vs.(76.5±39.7) mL], length of stay [(5.9±0.9) d vs.(9.6±1.3) d], blood β-HCG dropped to normal time [(17.9±8.7) d vs.(28.7±10.1) d] and menstruation recovery time [(18.1±1.6) d vs.(24.3±1.8) d],while the low-risk UAE group was better than the low-risk non UAE group in comparison of intraoperative bleeding [(93.2±43.3) mL vs.(284.8±110.5) mL], length of stay [(10.2±1.4) d vs. (30.7±9.6) d], blood β-HCG dropped to normal time [(50.1±17.6)d vs.(67.5±22.9)d] and menstruation recovery time[(56.3±6.7)d vs.(65.9±9.3) d], all P<0.05. The high-risk UAE group was higher than the high-risk non UAE group in comparison of hospitalization expenses [(20 140±1 520 )Yuan vs.(13 510±1 013) Yuan], and the low-risk group UAE was also higher than the low-risk non UAE group in comparison of hospitalization expenses [(10 095±962 )Yuan vs.(3 890±457) Yuan], all P<0.01. Multivariate Logistic regression analysis showed that the treatment method was independent predictor of CSP recurrence risk (OR 2.407, 95%CI 1.176-5.092, P<0.05), and using the comprehensive treatment including UAE could reduce the risk of recurrent CSP.

CONCLUSION

As the efficacy of interventional therapy for CSP was rapid and reliable, fewer complications, faster recovery and lower recurrence, hospitalization with good conditions, and particularly for those patients with CSP who want to fertility again, the comprehensive treatment including UAE treatment should be the first choice.

[Investigate the radical extent of lymphadenectomy of right colon cancer]

Considering radical surgeries of right colon cancer, the reasonable extent of lymphadenectomy has always been argued. The concept of complete mesocolic excision (CME) has recently been established and optimized, which follows similar oncological principles as total mesorectal excision (TME) does for rectal cancer and is recommended by more and more surgeons. Studies published so far in the literature have been comprehensively reviewed, they do not, however, provide convincing evidence that demonstrate the standardized operation indications. Moreover, the existence of potential surgical risk and discernible oncological benefit has not been determined. Thus future studies are needed to further investigate the safety and efficacy of CME surgery, as has been demonstrated with TME such that it should become the procedure of choice in surgical practice.

Changes in the PD-1 and PD-L1 expressions of splenic dendritic cells in multiple-organ dysfunction syndrome mice and their significance

The aim of this study was to evaluate the expression of surface molecules in splenic dendritic cells (DC) in multiple-organ dysfunction syndrome (MODS) mice and their effects on the immunosuppression of sepsis and MODS. One hundred thirty C57BL/6 mice were divided into 7 groups: 6, 12, 24, 48 h, 5-7 days, 10-12 days, and the normal control group. The sepsis-MODS mouse model was established by zymson injection into the peritoneal cavity. Histopathological changes in the spleen were evaluated by hematoxylin and eosin (HE) staining. After enrichment with BDTM IMag, the expressions of PD-1, PD-L1, MHC-II (I-A(b)), and CD86 in splenic DCs were examined by flow cytometry, and their relationship with sepsis development and MODS was analyzed. The histological structures of the spleen were damaged in the 24-, 48-h, and 10-12-day groups. PD-L1 expression increased 6 h after zymosan injection, decreased to normal levels at 24 and 48 h, and increased at 5-7 days, peaking at 10-12 days. The change in PD-1 expression roughly paralleled that of PD-L1. MHC-II and CD86 increased at 6 and 12 h, and dropped to normal levels at 10-12 days. In the early stage of injury, splenic DCs were mainly activated, whereas in the later stage, the expressions of the negative co-stimulatory molecules, PD-L1 and PD- 1, were upregulated, similar to tolerogenic DCs. Splenic DCs might suppress the stimulation of T lymphocytes in MODS mice through the PD-L1/PD-1 pathway, which would induce immunosuppression and the pathogenesis of MODS.

Transmission of avian influenza A(H7N9) virus from father to child: a report of limited person-to-person transmission, Guangzhou, China, January 2014

We investigated a possible person-to-person transmission within a family cluster of two confirmed influenza A(H7N9) patients in Guangzhou, China. The index case, a man in his late twenties, worked in a wet market that was confirmed to be contaminated by the influenza A(H7N9) virus. He developed a consistent fever and severe pneumonia after 4 January 2014. In contrast, the second case, his five-year-old child, who only developed a mild disease 10 days after disease onset of the index case, did not have any contact with poultry and birds but had unprotected and very close contact with the index case. The sequences of the haemagglutinin (HA) genes of the virus stains isolated from the two cases were 100% identical. These findings strongly suggest that the second case might have acquired the infection via transmission of the virus from the sick father. Fortunately, all 40 close contacts, including the other four family members who also had unprotected and very close contact with the cases, did not acquire influenza A(H7N9) virus infection, indicating that the person-to-person transmissibility of the virus remained limited. Our finding underlines the importance of carefully, thoroughly and punctually following-up close contacts of influenza A(H7N9) cases to allow detection of any secondary cases, as these may constitute an early warning signal of the virus's increasing ability to transmit from person-to-person.

Treatment with Fms-like tyrosine kinase 3 ligand reverses lung dendritic cell immunoparalysis and ameliorates zymosan-induced secondary lung injury in mice

Depletion and dysfunction of dendritic cells in the lung can induce local immunoparalysis, which often leads to multiple organ dysfunction syndrome (MODS)-associated mortality. A therapeutic strategy that reverses this immunoparalysis is required. In the present study, we examined the effects of in vivo Fms-like tyrosine kinase 3 ligand (Flt3L) treatment on zymosan (zym)-induced secondary lung injury and dendritic cell (DC) immunoparalysis. BALBc mice were divided randomly into four groups (20/group): (1) sham [intraperitoneal (i.p.) saline] + vehicle [subcutaneous (s.c.) 0·01% mouse serum albumin]; (2) sham + Flt3L (s.c.); (3) zym (i.p.) + vehicle; and (4) zym + Flt3L. Injections were for 9 consecutive days; 12 days later we examined: survival rate (monitored for 12 days); lung tissue histopathology (haematoxylin and eosin staining); plasma indices of lung function (pH, PaO(2) , PaCO(2) , HCO(3) (-) ); DC subsets in lung tissue; and lung DCs production of interleukin (IL)-12p70 and IL-10. Zym administration resulted in increased mortality associated with significant lung histopathological changes and abnormal blood gas indices; however, these pathological changes were ameliorated by Flt3L treatment. Zym injections also resulted in significant reductions in DC subsets recovered from lungs [CD11c(+) major histocompatibility complex (MHC)-II/I-A(d+) , CD11c(+) CD11b(+) and CD11c(+) B220(+) ]. Importantly, in-vivo Flt3L treatment reversed these trends for DC immunoparalysis by increasing the percentages of recovered DC subsets concomitant with increased DC production of IL-12 p70 and decreased IL-10 production. These results suggest that Flt3L may have therapeutic potential for reversing DC immunoparalysis and ameliorating lung injury secondary to MODS.

Cerebral microbleeds and depression in lacunar stroke

BACKGROUND AND PURPOSE

Cerebral microbleeds (CMB) are common in stroke survivors and the community-dwelling elderly. The clinical significance of CMB in the development of depression after a stroke is unknown. This study examined the association between poststroke depression (PSD) and CMB.

METHODS

A cohort of 235 patients with acute lacunar stroke admitted to the stroke unit of a university-affiliated regional hospital in Hong Kong was recruited. Three months after the onset of the index stroke, a research assistant administered the locally validated 15-item Geriatric Depression Scale. PSD was defined as a Genetic Depression Scale score of ≥7. The presence and location of CMB were evaluated with MRI.

RESULTS

In comparison with the non-PSD group, PSD patients were more likely to have lobar CMB (33.3% versus 19.9%; P=0.022). Lobar CMB remained an independent predictor of PSD in the multivariate analysis, with an odds ratio of 2.08 (P=0.032).

CONCLUSIONS

The results suggest that lobar CMB may play a role in the development of PSD. The importance of CMB in the pathogenesis of depression in stroke survivors and the general elderly population warrants further investigation.

The growth and characterization of ZnO/ZnTe core-shell nanowires and the electrical properties of ZnO/ZnTe core-shell nanowire field effect transistor

Vertically aligned ZnO/ZnTe core-shell nanowires were grown on a-plane sapphire substrate by using chemical vapor deposition with gold as catalyst for the growth of ZnO core and then followed by growing ZnTe shell using metal-organic chemical vapor deposition (MOCVD). Transmission electron microscope (TEM) and Raman scattering indicate that the core-shell nanostructures have good crystalline quality. Three-dimensional fluorescence images obtained by using laser scanning confocal microscope demonstrate that the nanowires have good optical properties. The core-shell nanowire was then fabricated into single nanowire field effect transistor by standard e-beam photolithography. Electrical measurements reveals that the p-type ZnO/ZnTe FET device has a turn on voltage of -1.65 V and the hole mobility is 13.3 cm2/V s.

Cerebral microbleeds and symptom severity of post-stroke depression: a magnetic resonance imaging study

BACKGROUND

Cerebral microbleeds (CMBs) are common in stroke survivors, although their clinical significance in the development of psychiatric conditions following stroke remains unknown. This study examines the association between post-stroke depression (PSD) symptom severity and CMBs.

METHODS

Amongst the 4088 patients with acute ischemic stroke who had been admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong, between December 2004 and May 2009, 994 patients were recruited. A psychiatrist administered the Structural Clinical Interview for DSM-IV to all 994 patients and made a diagnosis of PSD three months after the index stroke. PSD symptom severity was assessed with the 15-item Geriatric Depression Scale (GDS). Seventy-eight patients were found to have PSD. The presence and location of CMBs were evaluated with magnetic resonance imaging (MRI).

RESULTS

Seventy-eight patients (7.8%) had PSD. CMBs were identified in 20 PSD patients. Relative to the no-CMB group, the mean GDS score of patients with lobar CMBs was significantly higher (12.6±2.6 versus 10.4±2.5, p=0.01 after adjusting for age, sex, global cognitive functions, neurological deficits and white matter hyperintensities).

LIMITATIONS

Patients with more severe stroke, those who died before the three-month follow-up and those who became depressed later were excluded, as were those unable to give their consent due to dementia or aphasia. These selection biases may limit the generalizability of the findings.

CONCLUSIONS

The results suggest that lobar CMBs may contribute to PSD symptom severity. The importance of CMBs in the pathogenesis of other psychiatric disorders in stroke survivors and other patient populations warrants further investigation.

White matter hyperintensities in post-stroke depression: a case control study

OBJECTIVE

Despite extensive research on post-stroke depression (PSD), the role of white matter hyperintensities (WMHs) in its pathogenesis remains uncertain. The aim of this study was to evaluate the relationship between WMHs and PSD in Chinese patients with first or recurrent stroke.

METHODS

A cohort of 994 patients with acute ischaemic stroke admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong was recruited. A psychiatrist administered the Structural Clinical Interview for DSM-IV to all patients and made a diagnosis of PSD 3 months after the index stroke. 78 (7.8%) patients had PSD; 78 stroke patients matched according to age and sex but without PSD served as a control group. The severity and location of WMHs were evaluated with MRI.

RESULTS

In comparison with the non-PSD group, patients in the PSD group were more likely to have severe deep WMHs (12.8% vs 1.3%; p=0.009). Severe deep WMHs remained an independent predictor of PSD in the multivariate analysis with an OR of 13.8 (p=0.016).

CONCLUSION

The results suggest that WMHs may play a role in the development of PSD. The importance of WMHs in the treatment and outcome of PSD warrants further investigation.

Lipase from Pseudomonas fragi. I. Purification of the Enzyme

The experimental conditions required to isolate a lipase from Pseudomonas fragi were determined. The organism was grown in a buffered tryptone medium for 4 to 5 days at 20 C. The lipase in the culture supernatant fluid was isolated by fractionation with ammonium sulfate at 60% saturation, followed by acetone precipitation at 30-60% concentration. Further purification was made by using Sephadex G-200 gel-filtration and diethylaminoethyl cellulose chromatography. Electrophoretic analysis of the purified lipolytic fraction showed apparent homogeneity by both cellulose polyacetate and disc electrophoresis. The specific activity of the purified enzyme was about 100 times that of the starting culture filtrate, and the yield was about 1.8% of the original activity.

Optical singularities associated with the energy flow of two closely spaced core-shell nanocylinders

Optical singularities associated with the energy flow of two closely spaced dielectric-core gold-shell nanocylinders are studied by two-dimensional finite difference time domain method. The simulation results show that optical vortices as well as saddle points can be observed in the energy flow pattern of light interacting with the core-shell nanocylinder pair in its in-phase symmetric dipolar plasmon mode. The rotating direction of the optical vortices can be tuned by varying the width of the gap between the nanocylinder pair and the value of the permittivity of the dielectric core.

Microbleeds and post-stroke emotional lability

OBJECTIVE

The clinical significance of microbleeds (MBs) in the development of psychiatric conditions following a stroke is unknown. Lesions located in various cortical and subcortical areas are thought to be involved in the pathophysiology of post-stroke emotional lability (PSEL). This study examined the association between PSEL and MBs.

METHODS

A total of 519 Chinese patients with acute ischaemic stroke consecutively admitted to the acute stroke unit of a university affiliated regional hospital in Hong Kong were screened for PSEL 3 months after their index stroke. The number and location of MBs were evaluated with MRI.

RESULTS

According to Kim's criteria, 74 (14.3%) patients had PSEL. In comparison with the non-PSEL group, patients in the PSEL group were more likely to have MBs in the thalamus as a whole (16.2% vs 6.5%; p = 0.004), its anterior (6.9% vs 2.0%, p = 0.02) and paramedian territories (8.1% vs 3.1%; p = 0.04), and a higher number of MBs in the entire brain (1.7+3.4 vs 1.3+5.0; p = 0.031). MBs in the thalamus remained an independent predictor of PSEL in the multivariate analysis, with an odds ratio of 4.7 (p = 0.002).

CONCLUSION

Our results suggest that MBs in the thalamus may play a role in the development of PSEL. The importance of MBs in PSEL and other psychiatric conditions in stroke survivors warrants further investigation.

ipt Gene transformation in petunia by an Agrobacterium mediated method

To prevent leaf senescence of petunia, the cytokinin biosynthetic gene isopentenyl transferase (ipt) was placed under the control of 35S promoter and introduced into petunia. PCR analysis showed an expected 0.5 Kb fragment of ipt gene in transgenic petunia. RT-PCR analysis indicated the expression of ipt gene in the transgenic lines. Leaves from transgenic plants remained green and healthy in normal culture condition, while the non-transformed plants turned to yellow. Transgenic plants showed a reduction in height and smaller leaf sizes. In transgenic lines, the internodes were shorter, and the roots grew slower than the non-transformed plants.

A software environment for simulators suitable for complex biological analysis

In order to understand the function of biological elements and their interactions, computer analysis and simulation is an essential technique. For higher research efficiency, it is important to provide a system framework for constructing biological simulation systems that handle multiple phenomena. This paper proposes "DynaBioS", a comprehensive system framework for complex biological simulations. This framework consists of three main features, a component-based architecture, a customizable system operation, and an exchangeable model set. The system based on DynaBioS consists of a simulation core and system components. The system components are sub-simulators for individual functional factors and utility modules corresponding to specific information technologies. The simulation core manages and controls all components, in accordance with a simulation scenario and a simulation model. The DynaBioS makes it possible to implement different simulation systems by combining individual functional components, specific interactions and different simulation models. The versatility of DynaBioS is shown by two examples, a heart pumping simulator and a parameter optimization system for physiological models.

Field intercomparison studies for evaluation and validation of the AESminiSamplR technique for sampling and analysis of total particulate mercury in the atmosphere

This paper presents new data and reviews literature results from six field intercomparison studies to further evaluate and validate the AESminiSamplR [Anal. Chem., 70 (1998) 2403] technique for sampling and analysis of total particulate mercury in ambient air. The intercomparison studies were carried out at: two remote sites in the Arctic [Alert, Nunavut, Canada (82 degrees 28'N, 62 degrees 18'W) and Ny-Alesund, Svalbard (78 degrees 54'N, 11 degrees 53'E)], one site in Ann Arbor, MI, and three sites in Europe (one in Italy and two in Sweden). The AESminiSamplR was compared with five other methods using different materials, different flow rates, different sample treatment procedures, and/or different detection techniques. Four of the five methods compared were operated by different laboratories. When the compared methods were operated by different laboratories, a difference </=4 times was observed. When the compared methods were operated by the same laboratory, a maximum deviation of 1.3 times was achieved. These results demonstrate that the AESminiSamplR technique is a reliable, reproducible, simple, fast and cost-effective methodology for sampling and analysis of mercury associated with particulate matter in the atmosphere.

Consumer acceptance of vegetarian sweet potato products intended for space missions

Sweet potato is one of the crops selected for NASA's Advanced Life Support Program for potential long-duration lunar/Mars missions. This article presents recipes of products made from sweet potato and determines the consumer acceptability of products containing from 6% to 20% sweet potato on a dry weight basis. These products were developed for use in nutritious and palatable meals for future space explorers. Sensory evaluation (appearance/color, aroma, texture, flavor/taste, and overall acceptability) studies were conducted to determine the consumer acceptability of vegetarian products made with sweet potato using panelists at NASA/Johnson Space Center in Houston, TX. None of these products including the controls, contained any ingredient of animal origin with the exception of sweet potato pie. A 9-point hedonic scale (9 being like extremely and 1 being dislike extremely) was used to evaluate 10 products and compare them to similar commercially available products used as controls. The products tested were pancakes, waffles, tortillas, bread, pie, pound cake, pasta, vegetable patties, doughnuts, and pretzels. All of the products were either liked moderately or liked slightly with the exception of the sweet potato vegetable patties, which were neither liked nor disliked. Mean comparisons of sensory scores of sweet potato recipes and their controls were accomplished by using the Student t-test. Because of their nutritional adequacy and consumer acceptability, these products are being recommended to NASA's Advanced Life Support Program for inclusion in a vegetarian menu plan designed for lunar/Mars space missions.

Sweet potato in a vegetarian menu plan for NASA's Advanced Life Support Program

Sweet potato has been selected as one of the crops for NASA's Advanced Life Support Program. Sweet potato primarily provides carbohydrate--an important energy source, beta-carotene, and ascorbic acid to a space diet. This study focuses on menus incorporating two sets of sweet potato recipes developed at Tuskegee University. One set includes recipes for 10 vegetarian products containing fom 6% to 20% sweet potato on a dry weight basis (pancakes, waffles, tortillas, bread, pie, pound cake, pasta, vegetable patties, doughnuts, and pretzels) that have been formulated, subjected to sensory evaluation, and determined to be acceptable. These recipes and the other set of recipes, not tested organoleptically, were substituted in a 10-day vegetarian menu plan developed by the American Institute of Biological Sciences (AIBS) Kennedy Space Center Biomass Processing Technical Panel. At least one recipe containing sweet potato was included in each meal. An analysis of the nutritional quality of this menu compared to the original AIBS menu found improved beta-carotene content (p<0.05). All other nutrients, except vitamin B6, and calories were equal and in some instances greater than those listed for NASA's Controlled Ecological Life Support Systems RDA. These results suggest that sweet potato products can be used successfully in menus developed for space with the added benefit of increased nutrient value and dietary variety.

[Effects of repeated high +Gz exposure on several enzyme activities in cardiomyocytes in rats and some protective measures]

Objective. To determine the changes of several myocardial enzymes in rats after repeated high +Gz exposure and the protective effects of preconditioning of low-G exposure and tea polyphenols (TP). Method. Thirty-two male Wistar rats were randomly divided into 4 groups (n = 8 each): control group (group A), +10 Gz group (group B), low-G preconditioning group (group C) and TP protection group (group D). Group B, C and D were exposed to repeated +10 Gz stress (each for 30s, 5 times/d with +1 Gz 1 min intervals, 3 d/wk, 3 weeks in total), but group A was only submitted to +1 Gz for 5 min. Group C was exposed to +2 Gz for 5 min about 1 h prior to +10 Gz stress. Additionally, TP (200 mg/kg) was given orally to group D about 1 h prior to the +Gz experiment, while distilled water was given to groups A, B and C instead. On the next day after the last centrifuge run, the hearts were taken out immediately for making frozen tissue sections. Enzyme histochemical staining and image analysis were carried out for acid phosphatase (ACP), succinate dehydrogenase (SDH), cytochromeoxidase (Cyt aa3) and adenosine triphosphatase (ATPase). Result. As compared with the control, the activities of ACP and SDH in +10 Gz stressed rats decreased significantly (P<0.05), and there was a declining trend for Cyt aa3. But, low-G preconditioning and TP had protective effects on +10 Gz stress-induced reduction of these enzymatic activities (P<0.05). Conclusion. The results showed that repeated high +Gz exposure could bring about decreases of activities in ACP (the marker enzyme of lysosome) and SDH (the marker enzyme of mitochondrial endomembrane), which indicated a reduction of oxidative metabolism in myocardial tissue; but preconditioning with low-G and natural antioxidant TP had protective effects.