Expanded polyglutamine protein forms nuclear inclusions and causes neural degeneration in Drosophila

Spinocerebellar ataxia type 3 (SCA3/MJD) is one of at least eight human neurodegenerative diseases caused by glutamine-repeat expansion. We have recreated glutamine-repeat disease in Drosophila using a segment of the SCA3/MJD protein. Targeted expression of the protein with an expanded polyglutamine repeat led to nuclear inclusion (NI) formation and late-onset cell degeneration. Differential sensitivity to the mutant transgene was observed among different cell types, with neurons being particularly susceptible; NI formation alone was not sufficient for degeneration. The viral antiapoptotic gene P35 mitigated polyglutamine-induced degeneration in vivo. Our results demonstrate that cellular mechanisms of human glutamine-repeat disease are conserved in invertebrates. This fly model will aid in identifying additional factors that modulate neurodegeneration.     

Prevalence and disease experience rates in Korean physicians

This study aimed to find out the morbid status of Korean physicians living in Korea, as one part of a feasibility study on the Korean physician cohort. It was performed by mail survey using a self-administered questionnaire from Jan. 1, 1995 through Dec. 31, 1995. Study subjects were 21,552 including 17,877 (81.1%) males and 3,384 (15.5%) females. Person based prevalence rate of disease was 17.7% (18.3% for males and 13.8% for females) with the rate increasing with age. The disease group showing the highest prevalence rate was circulatory diseases (5.16%) for males, and respiratory disease (3.13%) for females. The individual disease showing the highest prevalence rates was hypertension (3.77%) for males and allergic rhinitis (2.25%) for females. The person based disease experience rate was 36.2% (36.9% for males, 32.7% for females) with the rate increasing with age. The disease group showing the highest disease experience rate was digestive disease for both sexes (10.05% for males, 7.42% for females). Individual disease showing the highest disease experience rate was hypertension (5.00%) for males and allergic rhinitis (4.08%) for females. There were different ranks of both prevalence and disease experience rate depending on age in both sexes.     

Structural analogues of cumambrin B from the flower of Chrysanthemum boreale

The structural analogues of cumambrin B (1, 2, 3, 4) were isolated from the flower of Chrysanthemum boreale Makino. The structures of compounds were determined by two-dimensional 1H-1H COSY and 13C-1H COSY spectra with the aid of homonuclear and heteronuclear double resonance experiment. The stereochemistry of compounds has been verified from single crystal X-ray diffraction of cumambrin A (2). The antimicrobial activities of these guaianolides have been studied.     

The lordotic effect of the OSI frame on operative adolescent idiopathic scoliosis patients

STUDY DESIGN: A prospective evaluation of adolescent idiopathic scoliosis patients undergoing operative treatment on the Orthopedic Systems Incorporated (OSI; Jackson) frame. OBJECTIVES: To investigate prospectively thoracic, thoracolumbar, and lumbar sagittal alignments in patients with adolescent idiopathic scoliosis who undergo an instrumented posterior spinal fusion on the OSI frame. SUMMARY OF BACKGROUND DATA: In several studies, it has been shown that patient positioning on various operative frames is an important component of ultimate lumbar sagittal alignment. However, these studies have all concentrated on the lumbar spine, and no sagittal plane alignment data in adolescent idiopathic scoliosis patients have been reported in the thoracic and thoracolumbar junction as it relates to intraoperative positioning, correction maneuvers and correlative postoperative results. METHODS: Thirty-nine patients with operative adolescent idiopathic scoliosis treated with an instrumented posterior spinal fusion on the OSI frame were prospectively evaluated. Standing preoperative, intraoperative, and postoperative long-cassette lateral radiographs were reviewed with regional and segmental Cobb measurements of the thoracic, thoracolumbar junction, and lumbar spine obtained. RESULTS: Thoracic kyphosis (T1-T12) measured +34 degrees before surgery, +28 degrees during surgery, and +30 degrees after surgery, Thus, a statistically significant decrease was noted in thoracic kyphosis secondary to prone positioning on the OSI frame ( P < 0.05). Thoracolumbar spine measurements from T10 to L2 also showed a lordotic trend from +2 degrees before surgery, to -4 degrees during surgery, to -8 degrees after surgery, which was also statistically significant (P < 0.05). Total lumbar lordosis from T12 to S1 remained relatively unchanged from -60 degrees before surgery, to -59 degrees during surgery, to -60 degrees after surgery. However, segmental lumbar lordosis measured from T12 to the lowest instrumented vertebra showed a statistically significant increase in lordosis from -17 degrees before surgery, to -19 degrees during surgery, to -23 degrees after surgery (P < 0.05). Those patients in whom lumbar pedicle screws were used (vs. hooks alone) had the greatest increase in lumbar instrumented lordosis. CONCLUSIONS: Performing adolescent idiopathic scoliosis correction on the OSI frame tends to decrease thoracic kyphosis, increase thoracolumbar lordosis, and increase segmental instrumented lumbar lordosis, while it maintains total lumbar lordosis.     

Evaluation of supermarket bagging using a wrist motion monitor

In previous studies, an RF magnetron sputter technique was developed for the production of thin calcium phosphate coating. Several deposition parameters were found to influence the growth rate and the stoichiometry of the coatings. For instance, deposition with additional oxygen pressure decreased the Ca to P ratio of the coatings to 1.67. For application of these coatings on actual Ti implants, it is important to know their adhesive tensile strength with the implant surface and how it varies with the deposition parameters. Motivated by these goals, the aim of this study was to measure the adhesive tensile strength of these coatings with Ti substrates and to study its variation with the deposition parameters. Since most mechanical characterization methods are incapable of providing a direct measure of the interface's fundamental strength, a novel laser spallation experiment was used to accomplish this task. In this experiment, a compressive stress pulse is generated on the back side of a substrate by impinging a 3-ns long Nd:YAG laser pulse. The stress pulse propagates through the substrate and is reflected into a tensile stress wave from the free surface of the coating deposited on its front surface. The returning tensile pulse pries off the coating if its amplitude is high enough. The peak interface tensile stress is computed by using the optically recorded free surface displacement of the coating. Because interface decohesion is accomplished at a strain rate of almost 10(7) s-1, all inelastic processes essentially are suppressed and the measured value essentially is the intrinsic tensile strength of the interface. Tensile strength values in the range of 500-900 MPa were recorded for the interfaces between sputter-deposited calcium-phosphate coatings and Ti substrates. To confirm the locus of failure, the spalled spots were examined using SEM and EDS. The variation in the measured values was related to the changes in the deposition conditions.     

Experimental hypercholesterolemia induces ultrastructural changes in the elastic laminae of rabbit aortic valve

The engraftment of hematopoietic stem and progenitor cells in lethally irradiated mice was evaluated following transplants of enriched hematopoietic cell populations which were defined by surface antigen and rhodamine-123 staining. Phenotypically defined long-term repopulating stem cells, short-term pluripotent progenitors, and committed myeloerythroid progenitors all rapidly reconstituted splenic cellularity and peripheral red blood cells after transplant into myeloablated animals. In contrast, marrow cellularity was reconstituted only after transplant of long-term repopulating stem cells. In addition, peripheral blood platelet and lymphocyte counts increased only after transplantation of the long-term repopulating population. Transplantation of highly enriched multipotent progenitors resulted in a transient increase in peripheral blood myeloid cells that occurred with kinetics similar to that seen after transplant of the primitive stem cell population. Erythroid reconstitution was similar in all groups, suggesting that the effect of myeloerythroid progenitor cells in mouse marrow transplants is primarily on reconstitution of the erythroid lineage due to splenic hematopoiesis. Collectively, these results suggest that the cells which function to rapidly reconstitute the nucleated blood cells in a transplant setting are more closely related to primitive, marrow-homing stem cells than to committed progenitor cells.     

Effect of tryptophan and of glucose on exercise capacity of horses

A method based on discounted income and risk assessment was developed to aid in the selection of dairy sires. The discounted profit generated from milk production of daughters was proposed as the suitable composite selection criterion to combine estimates of predicted transmitting ability (PTA) for yields of milk, fat, and protein and estimates of sire evaluations for dystocia or expected progeny difference. Steps are described to derive discounted profit (defined as expected income) for a sire with known PTA and evaluation for dystocia. The derivation of profit considered costs for semen, dystocia, heifer raising, production and maintenance of the daughter, and income from milk. Variance of income from a sire depended on the reliability of his PTA and evaluation for dystocia. Total variance from a selected set of sires was defined as the risk. A quadratic programming procedure was developed to identify the best set of sires from a given pool of sires that met a desired expected income goal with minimum risk. Combinations of sires with minimum risk for all possible levels of expected income were defined by the expected income variance frontier. The set of sires at the maximum lower boundary for 95% confidence of the expected income variance frontier was defined as the optimum set of sires to be selected; the optimum set maximized the 95% guaranteed expected income. The quadratic programming procedure provided the optimum percentage of cows to be mated to each sire in the selected set.     

In vivo quantitative mapping of cardiac perfusion in rats using a noninvasive MR spin-labeling method

Measurement of myocardial perfusion is important for the functional assessment of heart in vivo. Our approach is based on the modification of the longitudinal relaxation time T1 induced by magnetic spin labeling of endogenous water protons. Labeling is performed by selectively inverting the magnetization within the detection slice, and longitudinal relaxation is measured using a fast gradient echo MRI technique. As a result of blood flow, nonexcited spins enter the detection slice, which leads to an acceleration of the relaxation rate. Incorporating this phenomenon in a mathematical model that describes tissue as two compartments yields a simple expression that allows the quantification of perfusion from a slice-selective and a global inversion recovery experiment. This model takes into account the difference between T1 in blood and T1 in tissue. Our purpose was to evaluate the feasibility and reproducibility of this technique to map quantitatively myocardial perfusion in vivo in rats. Quantitative maps of myocardial blood flow were obtained from nine rats, and the reproducibility of the technique was evaluated by repeating the whole perfusion experiment four times. Evaluation of regions of interest within the myocardium yielded a mean perfusion value of 3.6 +/- .5 ml x min(-1) x g(-1) over all animals, which is in good agreement with previously reported literature values.