A coupled flow and transport model for simulation of groundwater reservoirs

As in many cases the quality of water, rather than the available amount restricts water use, a management of groundwater reservoirs has to include the investigation of the transport of dissolved solids in many cases. A special problem of coastal aquifers is a density dependent groundwater flow, caused by different saltwater concentration. For the efficient simulation of aquifer reaction a model is described, which permits the simultaneous computation of groundwater flow and mass transport.     

Hemodynamic assessment in managing the critically ill: is physician confidence warranted?

Our current knowledge of risk factors for Alzheimer's disease is limited and primarily addresses early-onset disease. This study aimed to determine the risk factors for late-onset Alzheimer's disease using a case-control approach. Ninety-eight cases and 216 controls were gathered from an ongoing population survey on aging and dementia in Stockholm (the Kungsholmen Project). We found a high relative risk (3.2; 95% confidence interval, 1.8-5.7) with the presence of at least one first-degree relative affected by dementia. Among all the other risk factors, alcohol abuse (relative risk, 4.4; 95% confidence interval, 1.4-13.8) and manual work (relative risk for men of 5.3; 95% confidence interval, 1.1-25.5) emerged as positively associated. No clear association was found with a family history of Parkinson disease, advanced parental age at index delivery, season of birth, or previous head trauma. In conclusion, our data suggest that the main risk factor for late-onset Alzheimer's disease is a family history of dementia, as has been previously reported for early-onset disease. Moreover, alcohol abuse and occupational exposure might play a specific role for this form of the disease.     

Reduction in postprandial lipemia after walking: influence of exercise intensity

Whole-body thermogenesis, substrate utilization (open-circuit ventilated-hood system), and exogenous carbohydrate oxidation were evaluated in 10 healthy lean male volunteers (aged 27.8 +/- 2.5 years) for 6 hours after oral ingestion of 75 g naturally enriched fructose, glucose (both derived from corn starch), cane sugar, and a good digestible corn starch (all mixed with 400 mL water). The integrated areas under the glucose and insulin response curves above baseline were highest with glucose and starch, intermediate with sucrose, and lowest with fructose, whereas there were no significant differences in the integrated nonesterified fatty acid (NEFA) response between carbohydrates. The total increment in energy expenditure (EE) above baseline was similar with fructose (130 +/- 24 kJ/6 h) and sucrose (141 +/- 17 kJ/6 h), was higher with sucrose as compared with starch (108 +/- 24 kJ/6 h, P < .05) and glucose (94 +/- 20 kJ/6 h, P < .05), and tended to be higher with fructose as compared with glucose (P = .059). Both the increment in total carbohydrate oxidation (P < .05) and the increment in exogenous carbohydrate oxidation (P < .01) were significantly higher with fructose and sucrose compared with glucose and starch. The initial inhibition of lipid oxidation was higher with sucrose and fructose than with glucose and starch, whereas the integrated decrement in lipid oxidation over 6 hours was only higher with fructose compared with glucose and starch (P < .05). In conclusion, thermogenesis and substrate utilization vary considerably after ingestion of different types of carbohydrate in young lean males, indicating that the carbohydrate composition of the diet may have important consequences for energy and macronutrient balance.     

Preparation of modified glycosyl glycerol derivatives by glycal rearrangement

By Lewis acid catalysed allylic rearrangement reactions of various glycals with glycerol derivatives 2,3-unsaturated mono- and disaccharide glycosyl glycerol derivatives were obtained in good yields. A triglycosyl glycerol was successfully synthesized in a straightforward three step way from 3,4,6-tri-O-acetyl-1,5-anhydro-2-deoxy-D-arabino-hex-1-enitol.     

Perioperative ischaemia in aortic surgery: combined epidural/general anaesthesia and epidural analgesia vs general anaesthesia and i.v. analgesia

PURPOSE: The goal of this randomized study was to determine whether combined general and epidural anaesthesia with postoperative epidural analgesia, compared with general anaesthesia and postoperative intravenous analgesia, reduced the incidence of perioperative myocardial ischaemia in patients undergoing elective aortic surgery. METHOD: Patients were randomly assigned to one of two groups. One group (EPI, n = 48) received combined general and epidural anaesthesia and postoperative epidural analgesia for 48 hrs. The other group (GA, n = 51) received general anaesthesia followed by postoperative intravenous analgesia. Anaesthetic goals were to maintain haemodynamic stability (+/- 20% of preoperative values), and a stroke volume > 1 ml.kg-1. A Holter monitor was attached to each patient the day before surgery. Leads 11, V2, and V5 were monitored. Myocardial ischaemia was defined as ST segment depression > 1 mm measured at 80 millisec beyond the J point or an elevation of 2 mm 60 millisec beyond the J point which lasted > 60 sec. An event that lasted > 60 sec but returned to the baseline for > 60 sec and then recurred, was counted as two separate events. The Holter tapes were reviewed by a cardiologist blind to the patient's group. RESULTS: There were no demographic differences between the two groups. Myocardial ischaemia was common; it occurred in 55% of patients. In hospital, preoperative ischaemia was uncommon (GA = 3, EPI = 8). Intraoperative ischaemia was common (GA = 18, EPI = 25). Mesenteric traction produced the largest number of ischaemic (GA = 11, EPI = 11) events. Postoperative ischaemia was most common on the day of surgery. Termination of epidural analgesia produced a burst of ischaemia (60 events in 9 patients). CONCLUSION: Combined general and epidural anaesthesia and postoperative epidural analgesia do not reduce the incidence of myocardial ischaemia or morbidity compared with general anaesthesia and postoperative intravenous analgesia.     

Nerve growth factor in normal and psoriatic skin equivalent models

Our objective was to determine the pattern and time course of nerve growth factor expression in an established skin equivalent model that we have used in the past to study wound healing and psoriasis phenotypes. Skin equivalents were constructed in triplicate using normal neonatal foreskin keratinocytes plated on collagen gels containing fibroblast lines. These lines were derived from five specimens of psoriatic lesions, three specimens of normal skin from patients with psoriasis, and three specimens of eyelid skin from normal donors. Immunohistochemistry and a monoclonal nerve growth factor-b antibody were used to determine the pattern of protein staining over 2 weeks. We looked at the wound healing phenotype using the skin equivalent model for 7-14 days. When keratinocytes invaginate into the dermis of skin equivalents (beginning at around 7 days of growth), dark staining of nerve growth factor was seen under the basal membrane zone, suggesting that nerve growth factor serves in the development of the basal membrane zone and the epidermis, and may influence the migration of nerves through the basal membrane zone into the regenerated skin.     

Development of sera reference panels for quality control of ELISA diagnostic kits in Russia

The clinico-immunological examination of 57 patients with chronic bacterial prostatitis was carried out. The clinical analysis made it possible to divide the patients into 3 groups characterized by the presence of chronic inflammatory diseases of other organs which had appeared before (group 1) or after (group 2) the manifestation of the symptoms of prostatitis, aw well as by the absence of concomitant inflammatory diseases (group 3). At the same time these patients were found to have changes in their immune status, most pronounced in patients of groups 1 and 2. The clinico-immunological analysis of the patients with chronic bacterial prostatitis revealed the fact that chronic bacterial prostatitis was a chronic inflammatory process linked with changes in the immune system; these changes had the signs of secondary immunodeficiency and required immunocorrective therapy.     

Kinetic investigation of cooperativity in coenzyme binding by transketolase active sites

The two-step mechanism of coenzyme (thiamine diphosphate, ThDP) binding with two initially identical active sites of apotransketolase has been examined with a kinetic model. Cooperativity between sites in the primary ThDP binding and in the following conformational transition has been analyzed. The only reliable difference between sites is shown to be the tenfold difference in the backward rate constants of the conformational transition; this means that the cooperative interaction between sites takes place only after termination of both steps of ThDP binding in both sites.