The BsmI vitamin D receptor restriction fragment length polymorphism (bb) influences the effect of calcium intake on bone mineral density

Previous studies of the vitamin D receptor (VDR) polymorphisms and bone mineral density (BMD) have suggested that there may be differences in calcium absorption among groups of women with different VDR genotypes, and that the association may be stronger in younger women. To investigate the association between the VDR polymorphisms and BMD, this study was undertaken in the Framingham Study Cohort and a group of younger volunteers. Subjects from the Framingham Study (ages 69-90 years) included those who underwent BMD testing and who had genotyping for the VDR alleles (n = 328) using polymerase chain reaction methods and restriction fragment length polymorphisms with BsmI (B absence, b presence of cut site). A group of younger volunteer subjects (ages 18-68) also underwent BMD testing and VDR genotyping (n = 94). In Framingham Cohort subjects with the bb genotype, but not the Bb or BB genotypes, there were significant associations between calcium intake and BMD at five of six skeletal sites, such that BMD was 7-12% higher in those with dietary calcium intakes greater than 800 mg/day compared with those with intakes < 500 mg/day. The data also suggested that BMD was higher in persons with the bb genotype only in the group with calcium intakes above 800 mg/day. No significant differences were found in the Framingham Cohort for age-, sex-, and weight-adjusted BMD at any skeletal site between those with the BB genotype and those with the bb genotype regardless of 25-hydroxyvitamin D levels or country of origin. In the younger volunteers, BMD of the femoral neck was 5.4% higher (p < 0.05) in the bb genotype group compared with the BB group and 11% higher (p < 0.05) in males with the bb genotype compared with the BB group. There were no significant differences at the lumbar spine. In this study, the association between calcium intake and BMD appeared to be dependent upon VDR genotype. The findings of an association between dietary calcium intake and BMD only in the bb genotype group suggests that the VDR genotype may play a role in the absorption of dietary calcium. Studies that do not consider calcium intake may not detect associations between VDR genotype and BMD. In addition, the association between VDR alleles and BMD may become less evident in older subjects.     

Genetic fusions of subunit c in the F0 sector of H+-transporting ATP synthase. Functional dimers and trimers and determination of stoichiometry by cross-linking analysis

The multicopy c subunit of the H+-transporting ATP synthase of Escherichia coli folds through the transmembrane F0 sector as a hairpin of two hydrophobic alpha-helices with the proton-translocating aspartyl-61 side chain centered in the second transmembrane helix. The number of subunits c in the F0 complex, which is thought to determine the H+-pumping/ATP stoichiometry, was previously not determined with exactness but thought to range from 9-12. The studies described here indicate that the exact number is 12. Based upon the precedent of the subunit c in vacuolar-type ATPases, which are composed of four transmembrane helices and seem to have evolved by gene duplication of an F0-type progenitor gene, we constructed genetically fused dimers and trimers of E. coli subunit c. Both the dimeric and trimeric forms proved to be functional. These results indicate that the total number of subunit c in F0 should be a multiple of 2 and 3. Based upon a previous study in which the oligomeric organization of c subunits in F0 was determined by cross-linking of Cys-substituted subunits (Jones, P. C. , Jiang, W., and Fillingame, R. H. (1998) J. Biol. Chem. 273, 17178-17185), we introduced Cys into the first and last transmembrane helices of subunit c monomers, dimers, and trimers and attempted to generate cross-linked products by oxidation with Cu(II)-(1,10-phenanthroline)2. Double Cys substitutions at two sets of positions gave rise to extensive cross-linked multimers. Multimers of the monomer that extended up to the position of c12 were correlated and calibrated with distinct cross-linked species of the appropriate doubly Cys-substituted dimers (i.e. c2, c4, . c12) and doubly Cys-substituted trimers (i.e. c3, c6, c9, c12). The results show that there are 12 copies of subunit c per F0 in E. coli, the exact number having both mechanistic and structural significance.     

Responsiveness of self-reported and objective measures of disease severity in carpal tunnel syndrome

Responsiveness, the ability to detect meaningful clinical change, is a critical attribute of instruments used to evaluate outcomes of treatments. The authors hypothesized that self-administered symptom severity and functional status questionnaires are more responsive to clinical improvement after carpal tunnel release than traditional physical examination measures of strength and sensibility. Data were obtained from a randomized clinical trial of endoscopic versus open carpal tunnel release conducted in four university medical centers. Patients were evaluated before surgery and 3 months after surgery. Seventy-four patients indicating that they were more than 80% satisfied with the results of surgery were assumed to have clinically meaningful improvement and were the focus of the analysis. Evaluations included questionnaires assessing symptom severity, functional status, and activities of daily living as well as measurement of grip, pinch, and abductor pollicus brevis strength, and 2-point discrimination and Semmes-Weinstein pressure sensibility. Responsiveness was calculated with the standardized response mean (mean change/standard deviation of change) as well as the effect size (mean change/standard deviation of baseline values). The symptom severity scale was four times as responsive, and the functional status and activities of daily living scales were twice as responsive, as the measures of strength and sensibility. Self-administered symptom severity and functional status scales are much more responsive to clinical improvement than measures of neuromuscular impairment and should severe as primary outcomes in clinical studies of therapy for carpal tunnel syndrome.     

Echinococcal disease and the provision of humanitarian surgical aid in Bosnia

The Canadian Armed Forced have been deployed to the republics of the former Yugoslavia since 1992 as part of the United Nations Protection Force and the NATO-led Implementation Force. Most of the combat arms units have been supported by small, self-contained surgical teams for essential surgery. Considerable benefit is gained by cooperating with civilian surgeons. The experience of treating five patients with complicated hydatid disease endemic to the area is examined. Treatment of these patients requires performing major surgical procedures under austere conditions and must be undertaken with care. Careful selection and communication with the surgical nursing team and civilian surgeons is essential. Well selected cases can also pay tremendous dividends in terms of maintaining the skills of personnel who must be prepared for any emergency in addition to providing vital surgical assistance to these patients.     

Protein adsorption onto poly(ether urethane ureas) containing Methacrol 2138F: a surface-active amphiphilic additive

Surface characterization and protein adsorption studies were carried out on a series of additive dispersed and additive coated poly(ether urethane ureas), PEUUs, to characterize early events in the blood compatibility of these materials. A hypothesis that is based on surface hydrophilicity, surface flexibility, and adsorption media has been developed to understand the modulated adsorption of plasma proteins by PEUU additives. Electron spectroscopy for chemical analysis (ESCA) and contact angle analysis were performed on two PEUU formulation as well as on PEUU formulations modified with Methacrol 2138F (co[diisopropylaminoethyl methacrylate (DIPAM)/decyl methacrylate (DM)][3/1]) or acrylate or methacrylate polymer or copolymer analogs of Methacrol 2138F. Methacrol 2138F is a commercially used amphiphilic copolymethacrylate. ESCA showed that the PEUUs loaded with Methacrol 2138F or with its hydrophilic component, homopoly (DIPAM) (h-(DIPAM)), had a higher percentage of nitrogen at their surfaces than did the base PEUUs. Contact angle analysis also showed that the air side of PEUU formulations loaded with Methacrol 2138F were more hydrophobic than was the air side of base PEUUs when films were cast from dimethylacetamide. However, during contact angle testing, the air side of PEUU films loaded with Methacrol 2138F rapidly became more hydrophilic than did the air side of the base PEUU films. A radioimmunoassay and whole or diluted human plasma were also used to characterize the presence of the proteins fibrinogen, immunoglobulin G, factor VIII/von Willebrand factor, Hageman factor (factor XII), and albumin, on the surface of the same PEUUs as analyzed by ESCA and contact angle. The protein adsorption assay showed that PEUU films loaded or coated with Methacrol 2138F, with a copolyacrylate analog of Methacrol 2138F (co(diisopropylaminoethyl acrylate [DIPAA]/decyl acrylate [DA]) [3/1]), or with the hydrophilic polyacrylate or polymethacrylate component analogs of Methacrol 2138F (h-DIPAM or h-DIPAA) adsorbed significantly lower amounts of the proteins than did either the base PEUU formulations or the homopoly(decyl methacrylate) (h-DM) or homopoly(decyl acrylate) (h-DA) coated or loaded PEUUs.     

A review of numerically controlled methods for finish-sculptured-surface machining

This paper presents a mathematical review of methods and algorithms used to compute milling cutter placement for multi-axis finished-surface machining. In general, these methods and algorithms compute tool path points based on tangent-plane contact between the milling cutter and the surface while maintaining a fixed tool orientation. This tangent-plane method of tool positioning and orientation is examined by discussing its strengths and weaknesses. Errors resulting from the tangent-plane approach are typically determined using a posteriori cutter path checking and graphic visualization techniques. Although these checking techniques have proved useful in identifying the tool path errors before actual machining, the problem of generating an error-free tool path remains. In this paper, we discuss the analysis of tool path position and orientation data as they are generated. This a priori analysis method is used to show error locations along the lateral face of the tool. The conclusion is reached that additional research is needed in the area of simultaneous multi-axis tool path planning, if errors are to be eliminated and the efficiency of the milling machine is to be improved. The reader is referred to research efforts that extend beyond the traditional or computer-aided design (CAD, vendor supplied) tool path planning methods. Some of these efforts show great promise in eliminating gouging and improves machine tool efficiency.     

Pancreaticoduodenectomy for selected periampullary neuroendocrine tumors: fifty patients

BACKGROUND: Most resectable pancreatic or peripancreatic neuroendocrine tumors are treated by enucleation or distal pancreatectomy. A minority of tumors may require pancreaticoduodenectomy for complete tumor excision because of their large size, location, or lymph node involvement. METHODS: This study reviews the management of 50 patients treated by pancreaticoduodenectomy for periampullary neuroendocrine tumors between 1962 and 1996 at a single institution. RESULTS: There were 30 men and 20 women with a mean age of 52 +/- 2 years. Functional tumors were resected in 17 patients: insulinoma, seven tumors; gastrinoma, eight tumors; vipoma, one tumor; and glucagonoma, one tumor. Tumors were classified as malignant in 29 patients and benign in 21. The median intraoperative blood loss was 800 ml, and the median number of units of blood transfused was zero. The postoperative length of stay was 20 +/- 2 days. Postoperative morbidity included 11 patients (24%) with a pancreatic fistula and four patients (8%) with a biliary fistula. There was one in-hospital death (2%), in 1967. The actuarial survival rates at 2, 5, and 7 years are 81%, 73%, and 65%, respectively. Patients with benign tumors had a significantly improved 5-year survival rate (94%) compared with those with malignant tumors (61%; p = 0.03). CONCLUSIONS: Selected patients with periampullary neuroendocrine tumors can be managed successfully by pancreaticoduodenectomy, with low mortality and acceptable morbidity rates.     

Dyspnea resulting from phrenic nerve paralysis after interscalene brachial plexus block in an obese male--a case report

While current psychiatric taxonomies recognise a classification of amphetamine dependence, derived from the notion of an alcohol dependence syndrome, little research has validated that such a condition exists for this drug. Current amphetamine users (N = 331), were interviewed using the World Health Organization operationalisation of DSM-III-R substance dependence criteria, and a measure of the psychological components of dependence. Structural analyses indicated that a unidimensional dependence syndrome as assessed by DSM-III-R and DSM-IV criteria exists for amphetamine, and that physiological, psychological and behavioural indicators were all important in accounting for the variance in responses. It was demonstrated that the concept of a dependence syndrome is applicable to amphetamine, and that the inclusion of the amphetamine dependence syndrome in DSM-III-R and DSM-IV is valid.     

Sperm numbers inseminated in dairy cattle and nonreturn rates revisited

Three experiments were conducted to test fertility when sperm numbers per insemination ranged from 10 x 10(6) to 40 x 10(6) total sperm. All semen was from Holstein bulls that were on a regular schedule of semen collection. The semen was extended with heated homogenized whole milk, cooled, glycerolated, and frozen according to standard procedures. Semen was distributed to a large group of inseminators to minimize differential field effects on treatment. All experiments were a randomized block design, including a split plot in Experiment 2. In Experiment 1, data for 31,399 first inseminations distributed among treatments of 20 x 10(6), 25 x 10(6), 30 x 10(6), and 40 x 10(6) total sperm resulted in 69.8, 70.0, 70.1, and 70.1% nonreturns at 59 d, respectively. In Experiment 2, data for 18,197 first inseminations divided over treatments of 12 x 10(6), 16 x 10(6), and 20 x 10(6) total sperm resulted in 70.2, 72.4, and 70.8% nonreturns at 59 d, respectively. In Experiment 3, 38,890 first inseminations distributed over treatments of 10 x 10(6), 13 x 10(6), 16 x 10(6), and 20 x 10(6) total sperm resulted in 70.5, 72.2, 73.1, and 71.5% nonreturns at 59 d, respectively. Bull nonreturns ranged from 64 to 76% in the three trials. These results indicate that, under good conditions, total sperm numbers per straw can be reduced to 10 x 10(6) total sperm with a reduction of nonreturn rates at 59 d, for most bulls, of about 1 percentage unit from the maximum when professional inseminators are use.