Significance of distal motor latency after carpal tunnel operation

Many microorganisms from the deep-sea display high-pressure-adapted--also described as barophilic or piezophilic--growth characteristics. Phylogenetic studies have revealed that a large proportion of the barophilic bacteria currently in culture collections belong to a distinct subgroup of the genus Shewanella, referred to as the "barophile branch." Many of the basic properties of barophiles that enable their survival at extremes of pressure remain to be elucidated. However, several genes whose expression is regulated by pressure, or which appear to be critical to baroadaptation, have been uncovered. One such operon, whose presence appears to be restricted to the "barophile branch," has been identified in DNA samples obtained from sediments recovered in the deepest ocean trench. In the case of another set of pressure-regulated genes, regulatory elements required for pressure signaling have been uncovered. The nature and regulation of these genes is discussed.     

Regulation of sodium-dependent phosphate transport in osteoclasts

Osteoclasts are the primary cells responsible for bone resorption. They are exposed to high ambient concentrations of inorganic phosphate (Pi) during the process of bone resorption and they possess specific Pi-transport system(s) capable of taking up Pi released by bone resorption. By immunochemical studies and PCR, we confirmed previous studies suggesting the presence of an Na-dependent Pi transporter related to the renal tubular "NaPi" proteins in the osteoclast. Using polyclonal antibodies to NaPi-2 (the rat variant), an approximately 95-kD protein was detected, localized in discrete vesicles in unpolarized osteoclasts cultured on glass coverslips. However, in polarized osteoclasts cultured on bone, immunofluorescence studies demonstrated the protein to be localized exclusively on the basolateral membrane, where it colocalizes with an Na-H exchanger but opposite to localization of the vacuolar H-ATPase. An inhibitor of phosphatidylinositol 3-kinase, wortmannin, and an inhibitor of actin cytoskeletal organization, cytochalasin D, blocked the bone-stimulated increase in Pi uptake. Phosphonoformic acid (PFA), an inhibitor of the renal NaPi-cotransporter, reduced NaPi uptake in the osteoclast. PFA also elicited a dose-dependent inhibition of bone resorption. PFA limited ATP production in osteoclasts attached to bone particles. Our results suggest that Pi transport in the osteoclast is a process critical to the resorption of bone through provision of necessary energy substrates.     

Assessment of glomerular filtration rate in diabetic nephropathy using the plasma clearance of 51Cr-EDTA

Tumor promotion/progression is known to be due in part to increased signaling through a variety of mitogenic pathways, including protein kinase C (PKC). To determine whether increased PKC activity could play a role in promotion and progression of renal cancer, we monitored PKC activity in normal and progressively transformed renal neoplasias from Eker rats. Eker rats carry a defect in the tumor suppressor TSC2 gene that predisposes them to renal carcinoma, whereas additional factors influence tumor promotion/progression in accordance with a "two-hit" model. We used the phosphorylation of adducins at Ser-660, a known PKC phosphorylation site, as a reporter for endogenous PKC activity. In normal proximal tubules, total adducin levels (measured with a phosphorylation state-insensitive antibody) were relatively high, whereas pSer660-adducin (measured with a phosphorylation state-sensitive antibody) levels were very low. In comparison, in renal carcinomas, total adducin levels were decreased, and pSer-660-adducin levels were increased. Changes in phosphorylation correlated with changes in localization. In normal tissue, alpha- and gamma-adducin are targeted to the apical and basal membranes of proximal tubules, respectively, implying unique functions for these related proteins. In early lesions (atypical tubules), differential targeting is lost, and both alpha- and gamma-adducins localize to the basal membrane. In more advanced lesions, staining in lateral membranes at cell-cell contacts becomes apparent. Furthermore, in cells that have lost basement membrane contact, plasma membrane targeting is no longer apparent. These changes in adducin expression levels, phosphorylation state, and localization parallel the increased growth potential and dedifferentiation of the progressive tumor phenotypes. These data demonstrate the utility of phosphorylation state-selective antibodies in immunohistochemical applications as reporters of endogenous PKC activity in tissue samples. We also provide the first evidence that increased PKC activity and phosphorylation of important target proteins occurs during progressive transformation in a non-phorbol ester tumor promotion model in vivo.     

Stability of matrix second-order systems: new conditions andperspectives

Modeling of many dynamic systems results in matrix second-order differential equations. In the paper, the stability issues of matrix second-order dynamical systems are discussed. In the literature, only sufficient conditions of stability and/or instability for a system in matrix second-order form are available. In this paper, necessary and sufficient conditions of asymptotic stability for time-invariant systems in matrix second-order form under different types of dynamic loadings (conservative/nonconservative) are derived and a physical interpretation is carried out. The stability conditions in the sense of Lyapunov (the jw-axis behavior of eigenvalues) are also analyzed. As the conditions are gained directly in terms of physical parameters of the system, the effect of different loadings on the system stability is made transparent by dealing with the stability issues directly in matrix second-order form     

Minimization of water consumption under uncertainty for a pulverized coal power plant

Coal-fired power plants are large water consumers. Water consumption in thermoelectric generation is strongly associated with evaporation losses and makeup streams on cooling and contaminant removal systems. Thus, minimization of water consumption requires optimal operating conditions and parameters, while fulfilling the environmental constraints. Several uncertainties affect the operation of the plants, and this work studies those associated with weather. Air conditions (temperature and humidity) were included as uncertain factors for pulverized coal (PC) power plants. Optimization under uncertainty for these large-scale complex processes with black-box models cannot be solved with conventional stochastic programming algorithms because of the large computational expense. Employment of the novel better optimization of nonlinear uncertain systems (BONUS) algorithm, dramatically decreased the computational requirements of the stochastic optimization. Operating conditions including reactor temperatures and pressures; reactant ratios and conditions; and steam flow rates and conditions were calculated to obtain the minimum water consumption under the above-mentioned uncertainties. Reductions of up to 6.3% in water consumption were obtained for the fall season when process variables were set to optimal values. Additionally, the proposed methodology allowed the analysis of other performance parameters like gas emissions and cycle efficiency which were also improved.     

Process design for the environment: A multi-objective framework under uncertainty

 Designing chemical processes for the environment requires consideration of several indexes of environmental impact including ozone depletion, global warming potentials, human and aquatic toxicity, photochemical oxidation, and acid rain potentials. Current methodologies, such as the generalized waste reduction algorithm (WAR), provide a first step towards evaluating these impacts. However, to address the issues of accuracy and the relative weights of these impact indexes, one must consider the problem of uncertainties. Environmental impacts must also be weighted and balanced against other concerns, such as their cost and long-term sustainability. These multiple, often conflicting, goals pose a challenging and complex optimization problem, requiring multi-objective optimization under uncertainty. This paper will address the problem of quantifying and analyzing the various objectives involved in process design for the environment. Towards this goal, we proposed a novel multi-objective optimization framework under uncertainty. This framework is based on new and efficient algorithms for multi-objective optimization and for uncertainty analysis. This approach finds a set of potentially optimal designs where trade-offs can be explicitly identified, unlike cost-benefit analysis, which deals with multiple objectives by identifying a single fundamental objective and then converting all the other objectives into this single currency. A benchmark process for hydrodealkylation (HDA) of toluene to produce benzene modeled in the ASPEN simulator is used to illustrate the usefulness of the approach in finding environmentally friendly and cost-effective designs under uncertainty. Received: 8 February 2000 / Accepted: 10 March 2000     

Long-term effect of lisinopril and atenolol on kidney function in hypertensive NIDDM subjects with diabetic nephropathy

The aim of our study was to evaluate whether inhibition of ACE (lisinopril 10-20 mg/day) can reduce the rate of decline in kidney function more than reducing blood pressure with conventional antihypertensive treatment (atenolol 50-100 mg/day), usually in combination with a diuretic. We performed a prospective, randomized, parallel study for 42 months, double blind for the first 12 months and single blind thereafter. Forty-three (21 lisinopril and 22 atenolol) hypertensive NIDDM patients with diabetic nephropathy were enrolled. Data from 36 patients (17 lisinopril and 19 atenolol, 60 +/- 7 years of age, 27 men) who completed at least 12 months of the study period are presented. At baseline, the two groups were comparable: glomerular filtration rate (51Cr-EDTA plasma clearance) was 75 +/- 6 and 74 +/- 8 ml x min(-1) x 1.73 m(-2), mean 24-h ambulatory blood pressure (A&D TM2420) was 110 +/- 3 and 114 +/- 2 mmHg, and 24-h urinary albumin excretion rate was 961 (range 331-5,727) and 1,578 (476-5,806) mg/24 h in the lisinopril and atenolol groups, respectively. The mean follow-up time was similar, 37 and 35 months in the lisinopril and atenolol groups, respectively. Mean ambulatory blood pressure was equally reduced in the two groups, 12 +/- 2 and 10 +/- 2 mmHg in the lisinopril and atenolol groups, respectively. Glomerular filtration rate declined in a biphasic manner with a faster initial (0 to 6 months) change of 1.25 +/- 0.49 and 0.81 +/- 0.29 ml x min(-1) x month(-1) followed by a slower sustained decline (6 to 42 months) of 0.59 +/- 0.10 and 0.54 +/- 0.13 ml x min(-1) x month(-1) in the lisinopril and atenolol groups, respectively. No significant differences were observed in either initial or sustained decline in glomerular filtration rate between the two groups. Urinary albumin excretion was reduced (% reduction of baseline) more in the lisinopril than in the atenolol group, at 55 (95% CI 29-72) and 15% (-13 to 34), respectively (P = 0.01). In conclusion, the relentless decline in kidney function characteristically found in hypertensive NIDDM patients with diabetic nephropathy can be reduced equally effectively by two antihypertensive treatments, the beta-blocker atenolol and the ACE inhibitor lisinopril.     

The effectiveness of a school-based fluoride mouth rinse programme

The objective of this study was to determine the effectiveness of unsupervised weekly fluoride mouth rinsing (FMR) with 10 mls of 0.2 per cent sodium fluoride on the caries increment of permanent teeth in schoolchildren aged 6-12 years over a 3 year period. Caries was assessed using DMFT and DMFS indices (WHO, 1987). Over 2000 children from 4 schools in the Johannesburg area were selected at baseline. For analysis purposes pupils were pooled into 2 groups, those who received and those who did not receive the FMR. There were significant differences in mean decayed scores after 3 years. The percentage caries reduction achieved with the FMR was approximately 15 per cent. Reductions of up to 30 per cent have been recorded in previous studies of this nature. The overall caries reduction for this study period can be considered low.