Physiologic stress responses to laparoscopic cholecystectomy. A comparison of the gasless and pneumoperitoneal procedures

BACKGROUND: Differences in the physiological stress response to pneumoperitoneal (PP) and gasless abdominal wall-lifting (AWL) procedures used for laparoscopic cholecystectomy have not been properly evaluated. METHODS: We compared leukocyte count, interleukin-6 (IL-6) levels, arterial blood gases, creatinine clearance, plasma renin activity, cardiothoracic ratio, and clinical outcome in 27 patients without systemic complications who underwent laparoscopic cholecystectomy, including 11 by AWL and 16 by PP. RESULTS: Transient leukocytosis and high IL-6 levels were observed at POD 1 (postoperative day) in both groups, but both values returned to baseline by POD 2. IL-6 levels correlated significantly with operation time (p < 0.01). Changes in blood gases, creatinine clearance, plasma renin activity, and cardiothoracic ratio were not different for the two groups. The clinical outcome was similar for both groups. CONCLUSIONS: Our results indicate that both PP and AWL are appropriate for patients without serious complications.     

New predictive formulas of pulmonary function in Japanese children

Socioeconomic conditions, including nutrition, have improved dramatically over the past four decades in Japan. Those improvements have elicited significant changes in the developmental growth and average size of Japanese children. These trends suggest that predictive formulas of pulmonary function need to be revised. Our study enrolled 446 children (222 boys and 224 girls ranging in age from 5 to 16 years) who had no history of respiratory disease. The subjects were examined by spirometry. We formulated regression equations for several measures of ventilatory function by age, weight, and height, including vital capacity (VC), forced vital capacity (FVC), and forced expiratory volume in one second (FEV1.0), using data randomly selected from 70% of the children. Optimum parameters for the equations were selected by calculating Akaike information criteria (AIC) and Mallow's index C (p). The optimum regression equations were tested for their predictive value as acceptable predictive formulas by evaluating data randomly selected from 30% of the children. These new formulas are considered to be better suited for modern-day evaluations of pulmonary function in Japanese children.     

Placement of endosteal implants combined with chin bone onlay graft for dental reconstruction in patients with grafted alveolar clefts

CONTEXT: Physical activity and fitness are believed to reduce premature mortality, but whether genetic factors modify this effect is not known. OBJECTIVE: To investigate leisure physical activity and mortality with respect to familial aggregation of health habits during childhood and factors that may enable some individuals to achieve higher levels of fitness. DESIGN: Prospective twin cohort study. SETTING: Finland. SUBJECTS: In 1975, at baseline, 7925 healthy men and 7977 healthy women of the Finnish Twin Cohort aged 25 to 64 years who responded to a questionnaire on physical activity habits and known predictors of mortality. Those who reported exercising at least 6 times per month with an intensity corresponding to at least vigorous walking for a mean duration of 30 minutes were classified as conditioning exercisers, those who reported no leisure physical activity were classified as sedentary, and other subjects were classified as occasional exercisers. MAIN OUTCOME MEASURES: All-cause mortality and discordant deaths among same-sex twin pairs from 1977 through 1994. RESULTS: Among the entire cohort, 1253 subjects died. The hazard ratio for death adjusted for age and sex was 0.71 (95% confidence interval [CI], 0.62-0.81) in occasional exercisers and 0.57 (95% CI, 0.45-0.74) in conditioning exercisers, compared with those who were sedentary (Pfor trend <.001). Among the twin pairs who were healthy at baseline and discordant for death (n=434), the odds ratio for death was 0.66 (95% CI, 0.46-0.94) in occasional exercisers and 0.44 (95% CI, 0.23-0.83) in conditioning exercisers compared with those who were sedentary (P for trend, .005). The beneficial effect of physical activity remained after controlling for other predictors of mortality. CONCLUSION: Leisure-time physical activity is associated with reduced mortality, even after genetic and other familial factors are taken into account.     

Comparison of biomechanical properties of the incisor periodontal ligament among different species

BACKGROUND: The aim of this study was to obtain a more precise understanding of the mechanical properties of the periodontal ligament in continuously erupting incisors by comparing the shear stress-strain relations among teeth from four closely related species. METHODS: Four species of experimental animals (mice, hamsters, rats, and rabbits) were used. Transverse sections of the left mandibular incisors were cut from the incisal, middle, and basal regions of each incisor. The tooth was pushed out of the alveolar bone in an extrusive direction at 5 mm/min using a materials testing machine. The maximum shear stress, maximum shear strain, tangent modulus, and failure strain energy density were estimated from the resulting stress-strain curve. Polarized light microscopic observations of collagen fibers were also made. RESULTS: All the biomechanical measures tended to decrease from the incisal toward the basal regions in all species. There were large species differences, especially in the incisal region, with the greatest maximum shear stress and failure strain energy density in hamsters. The greatest tangent modulus and the smallest maximum shear strain were observed in mice. The birefringent fiber architectures of the periodontal ligaments in the four species appeared to be similarly organized; the incisal periodontal ligament appeared to have more organized and thicker collagen fibres than did the middle and basal ligaments in the four species. CONCLUSIONS: These results suggest that the regional differences in the biomechanical properties of the periodontal ligament depend upon the developmental stages of the periodontal collagen fibers that may be related to the general arrangement, diameters, and densities of the collagen fiber bundles and the fiber insertions into the alveolar bone and cementum. The species differences in the biomechanical properties may be due to differences in the width of the periodontal ligament and the waviness as well as the strength and stiffness of the periodontal collagen fibers.     

Fate of herbicide CNP in rivers and agricultural drainages

The occurrence and fate of a herbicide CNP (2,4,6-trichlorophenyl-4′-nitrophenylether) in rivers and agricultural drainages was investigated. CNP residues in water samples were extracted by adsorption on a macroreticular XAD-2 resin column and subjected to gas chromatographic analysis using an electron capture detection after desorption from the column and concentration. The minimum detectable amount was 0.04 ng and a positive identification of CNP residue in water samples was obtained with a combined gas chromatography-mass spectrometry-computer system when 500 ng of CNP was injected. CNP residues were detected in water samples taken in June to September, and these levels were between 0.01 and 16.67 μg l⁻¹. The maximum level was found in a sample taken on 13th July, 1977, about a month after beginning rice seedling transplantation, and the minimum level was detected on August 29th, 1977. However CNP residue levels were increased again in September because flooded water on the paddy fields was excluded. CNP was more persistent in the aquatic environment than a herbicide benthiocarb.     

New method for determining distribution of interface states in an MIS system

A general formula for the capacitance transient response in an MIS system was developed in order to apply the ICTS (isothermal capacitance transient spectroscopy) technique to an MIS diode. A new spectroscopic measurement method for determining the distribution of interface states is proposed and applied to an InAs MIS diode.     

Asymmetric addition of thiol to diene polymer in the presence of optically active amines as catalyst

The asymmetric addition reaction of thiolacetic acid or benzylmercaptan to diene polymer (natural rubber, cis- and trans-1,4-polyisoprene, _cis-1,4-polybutadiene, various styrenebutadiene copolymers and alternating acrylonitrile-butadiene copolymer) by optically active catalysts such as d-bornylamine ([α]d?45.2°), l-aspartic diethyl ester (?11.2°), l-aspartic dibutyl ester (?5.3°) were carried out in benzene at room temperature to 90°C. The optically active polymers were obtained from natural rubber and cis-1,4- and trans-1,4-polyisoprene, but were not obtained from cis-1,4-polybutadiene, styrene-butadiene copolymers, and butadiene-acrylonitrile copolymer. The [α]²⁵_D value of optically active derivatives was ?0.1° ～ ?1.0° (in benzene), and the optical rotatory dispersion curves were found to fit the simple Drude equation.     

Self-assembly of a silica-surfactant nanocomposite in a porous alumina membrane

A mesoporous membrane composed of nanochannels with a uniform diameter has a potential use for precise size-exclusive separation of molecules. Here, we report a novel method to form a hybrid membrane composed of silica-surfactant nanocomposite and a porous alumina membrane, by which size-selective transport of molecules across the membrane becomes possible. The nanocomposite formed inside each columnar alumina pore was an assembly of surfactant-templated silica-nanochannels with a channel diameter of 3.4 nm; the channel direction being predominantly oriented along the wall of the columnar alumina pore. Molecules could be transported across the membrane including the silica-surfactant nanocomposite with a capability of nanometre-order size-exclusive separation. Our proposed membrane system has a potential use not only for separation science, but also catalysis and chip technologies.