Improvements to the in vivo measurement of cadmium in the kidney by neutron activation analysis

The McMaster University in vivo cadmium measurement system has been upgraded. Two large surface area hyperpure germanium planar detectors (51 mm diameter x 21 mm depth) are now employed for the detection of the 559 keV gamma-ray signal from cadmium. Phantom studies indicate that the new detectors have significantly improved the system. The detection limit in kidney phantoms has been reduced from 8.9 to 3.8 mg for the same dose and measurement time.     

Frequent nut consumption and risk of coronary heart disease in women: prospective cohort study

OBJECTIVE: To examine the relation between nut consumption and risk of coronary heart disease in a cohort of women from the Nurses' Health Study. DESIGN: Prospective cohort study. SETTING: Nurses' Health Study. SUBJECTS: 86 016 women from 34 to 59 years of age without previously diagnosed coronary heart disease, stroke, or cancer at baseline in 1980. MAIN OUTCOME MEASURES: Major coronary heart disease including non-fatal myocardial infarction and fatal coronary heart disease. RESULTS: 1255 major coronary disease events (861 cases of non-fatal myocardial infarction and 394 cases of fatal coronary heart disease) occurred during 14 years of follow up. After adjusting for age, smoking, and other known risk factors for coronary heart disease, women who ate more than five units of nuts (one unit equivalent to 1 oz of nuts) a week (frequent consumption) had a significantly lower risk of total coronary heart disease (relative risk 0.65, 95% confidence interval 0.47 to 0.89, P for trend=0.0009) than women who never ate nuts or who ate less than one unit a month (rare consumption). The magnitude of risk reduction was similar for both fatal coronary heart disease (0.61, 0.35 to 1.05, P for trend=0.007) and non-fatal myocardial infarction (0.68, 0.47 to 1.00, P for trend=0.04). Further adjustment for intakes of dietary fats, fibre, vegetables, and fruits did not alter these results. The inverse association persisted in subgroups stratified by levels of smoking,use of alcohol, use of multivitamin and vitamin E supplements, body mass index, exercise, and intake of vegetables or fruits. CONCLUSIONS: Frequent nut consumption was associated with a reduced risk of both fatal coronary heart disease and non-fatal myocardial infarction. These data, and those from other epidemiological and clinical studies, support a role for nuts in reducing the risk of coronary heart disease.     

Use of a prognostic treadmill score in identifying diagnostic coronary disease subgroups

BACKGROUND: Exercise testing is useful in the assessment of symptomatic patients for diagnosis of significant or extensive coronary disease and to predict their future risk of cardiac events. The Duke treadmill score (DTS) is a composite index that was designed to provide survival estimates based on results from the exercise test, including ST-segment depression, chest pain, and exercise duration. However, its usefulness for providing diagnostic estimates has yet to be determined. METHODS AND RESULTS: A logistic regression model was used to predict significant (>/=75% stenosis) and severe (3-vessel or left main) coronary artery disease, and a Cox regression analysis was used to predict cardiac survival. After adjustment for baseline clinical risk, the DTS was effectively diagnostic for significant (P<0.0001) and severe (P<0.0001) coronary artery disease. For low-risk patients (score >/=+5), 60% had no coronary stenosis >/=75% and 16% had single-vessel >/=75% stenosis. By comparison, 74% of high-risk patients (score <-11) had 3-vessel or left main coronary disease. Five-year mortality was 3%, 10%, and 35% for low-, moderate-, and high-risk DTS groups (P<0.0001). CONCLUSIONS: The composite DTS provides accurate diagnostic and prognostic information for the evaluation of symptomatic patients evaluated for clinically suspected ischemic heart disease.     

Laboratory evaluation of tissue heart valves. A comparative assessment

Tissue of commercially prepared tissue heart valves were evaluated and compared with aluminium treated, fixed porcine valve tissue in vitro (tensile strength, scanning and transmission electron microscopy) and in vivo (calcification potential after subcutaneous implantation in the rat model). Valve leaflets (n = 40) were divided into four groups according to the method of treatment: Group I (fixed in 0.652% glutaraldehyde, control), Group II (fixed and treated with aluminium), Group III (fixed and treated with Toluidine blue) and Group IV (fixed and treated with watersoluble alkyl sulphate). Tensile strength was not influenced in Group II and III (p > 0.05). Group IV indicated a significant (p < 0.05) reduction in tensile strength. Scanning electron microscopy revealed damage and loss of surface endothelium in Group III and IV respectively. Transmission electron microscopy indicated damage to underlying matricial cells in Group III and IV. Calcification potential was significantly (p < 0.001) reduced in Group II to IV. We conclude that damage ultrastructure could contribute to the reduced tensile strength in Group IV and that reduced tensile strength might have an influence on the long-term durability of tissue heart valves. Antimineralization treatment of tissue heart valves does retard calcification but is yet unable to inhibit the process completely.     

Rectal trauma: management based on anatomic distinctions

Principles of rectal wound management, including routine diversion, injury repair, presacral drainage and distal washout, evolved from World War II and the Vietnam conflict and have been questioned in recent years. We believe significant confusion arises because of imprecise definition of injury location relative to retroperitoneal involvement. Our 5-year experience with penetrating rectal injuries at a Level I trauma center was analyzed. Injuries to the anterior and lateral surfaces of the upper two-thirds of the rectum were classified as intraperitoneal (IP, serosalized), and those of the posterior surface extraperitoneal (EP, no serosa); injuries to the lower one-third were EP. A total of 58 injuries were managed (92% gunshot wounds). Of these, 16 were IP, and 42 had some EP component. Ten patients underwent repair without diversion (6 IP, 4 EP); there were no leaks. Ten septic complications occurred in the remaining population: 2 necrotizing fasciitis, 5 abdominal abscess, and 3 presacral infections (PIs) (2 presacral abscesses and 1 wound tract infection). PI is the only complication that can be specifically associated with EP rectal injuries relative to management; as associated injury confounds interpretation of the other complications. The operative management in the 38 patients with diverted EP wounds with respect to presacral infection (PI) demonstrated the following: repair injury (n = 10), 0 PI versus no repair (n = 28), 3 PI (P = 0.55); washout (n = 33), 2 PI versus no washout (n = 5), 1 PI (P = 0.35); presacral drain (n = 30), 1 PI versus no drain (n = 8), 2 PI (P = 0.11). We conclude that most IP injuries can be managed with primary repair. EP wounds to the upper two-thirds of the rectum should usually be repaired. EP wounds to the lower one-third, which are explored and repaired, do not require drainage. EP wounds that are not explored should be managed with presacral drainage to minimize the incidence of presacral abscess.     

Anthelmintic beta-hydroxyketoamides (BKAs)

We have prepared several anthelmintic coumarins based on the beta-hydroxyketoamide (BKA) template and have shown that this template remains valid over a wide range of changes to the coumarin moiety allowing for the inclusion of carbocyclic, bicyclic, and heterocyclic rings.     

Role of the negative charges in the cytosolic domain of TOM22 in the import of precursor proteins into mitochondria

TOM22 is an essential mitochondrial outer membrane protein required for the import of precursor proteins into the organelles. The amino-terminal 84 amino acids of TOM22 extend into the cytosol and include 19 negatively and 6 positively charged residues. This region of the protein is thought to interact with positively charged presequences on mitochondrial preproteins, presumably via electrostatic interactions. We constructed a series of mutant derivatives of TOM22 in which 2 to 15 of the negatively charged residues in the cytosolic domain were changed to their corresponding amido forms. The mutant constructs were transformed into a sheltered Neurospora crassa heterokaryon bearing a tom22::hygromycin R disruption in one nucleus. All constructs restored viability to the disruption-carrying nucleus and gave rise to homokaryotic strains containing mutant tom22 alleles. Isolated mitochondria from three representative mutant strains, including the mutant carrying 15 neutralized residues (strain 861), imported precursor proteins at efficiencies comparable to those for wild-type organelles. Precursor binding studies with mitochondrial outer membrane vesicles from several of the mutant strains, including strain 861, revealed only slight differences from binding to wild-type vesicles. Deletion mutants lacking portions of the negatively charged region of TOM22 can also restore viability to the disruption-containing nucleus, but mutants lacking the entire region cannot. Taken together, these data suggest that an abundance of negative charges in the cytosolic domain of TOM22 is not essential for the binding or import of mitochondrial precursor proteins; however, other features in the domain are required.     

Electrochemical polymerization of chiral pyrrole derivatives in electrolytes containing chiral camphor sulfonic acid

N‐Substituted pyrrole derivatives with chiral side groups have been synthesized and electrochemically polymerized in acetonitrile containing tetrabutylammonium perchlorate (TBAClO₄) and (S)‐(+)‐camphor‐10‐sulfonic acid ((S)‐(+)‐CSA) or (R)‐(?)‐camphor‐10‐sulfonic acid ((R)‐(?)‐CSA). The resulting N‐substituted polypyrrole films were characterized by cyclic voltammetry, infrared, Raman and X‐ray photoelectron (XPS) spectroscopies. XPS results demonstrated that the as‐grown polymer films are preferably doped by CSA anions when the monomer and the CSA anion have the same optical rotation dispersion (ORD). Furthermore, the conductivities of the polymers synthesized in the media containing CSA with the same ORD of the corresponding monomers were measured to be about 2–10 times higher than those of polymers obtained from electrolytes without CSA. Copyright © 2004 Society of Chemical Industry