Nitric oxide and beta-adrenergic agonist-induced bronchial arterial vasodilation

In anesthetized sheep, we measured bronchial blood flow (Qbr) by an ultrasonic flow probe to investigate the interaction between inhaled nitric oxide (NO; 100 parts/million) given for 5 min and 5 ml of aerosolized isoetharine (1.49 x 10(-2) M concentration). NO and isoetharine increased Qbr from 26.5 +/- 6.5 to 39.1 (SE) +/- 10.6 and 39.7 +/- 10.7 ml/min, respectively (n = 5). Administration of NO immediately after isoetharine further increased Qbr to 57.3 +/- 15.1 ml/min. NO synthase inhibitor N(omega)-nitro-L-arginine methyl ester hydrochloride (L-NAME; 30 mg/kg, in 20 ml saline given i.v.) decreased Qbr to 14.6 +/- 2.6 ml/min. NO given three times alternately with isoetharine progressively increased Qbr from 14.6 +/- 2.6 to 74.3 +/- 17.0 ml/min, suggesting that NO and isoetharine potentiate vasodilator effects of each other. In three other sheep, after L-NAME three sequential doses of isoetharine increased Qbr from 10.2 +/- 3.4 to 11.5 +/- 5.7, 11.7 +/- 4.7, and 13.3 +/- 5.7 ml/min, respectively, indicating that effects of isoetharine are predominantly mediated through synthesis of NO. When this was followed by three sequential administrations of NO, Qbr increased by 146, 172, and 185%, respectively. Thus in the bronchial circulation, there seems to be a close interaction between adenosine 3',5'-cyclic monophosphate- and guanosine 3',5'-cyclic monophosphate-mediated vasodilation.     

Liquid titanium solute diffusion measured by pulsed ion-beam melting

The diffusivities of Sn, Mo, Zr, and Hf in liquid Ti were determined by pulsed ion-beam melting of thin liquid layers. Time-resolved optical reflectance and one-dimensional heat-flow simulations were employed to determine the melt duration. The broadening of nearly Gaussian solute concentration-depth profiles was determined ex situ using Rutherford backscattering spectrometry. Solute diffusivities in the range of 5 to 9×10⁻⁵ cm²/s were determined at temperatures in the range of 2200 to 2500 K. Calculations of buoyancy and Marangoni convection indicate that convective contamination is unlikely.     

Mother's emotional expressivity and children's behavior problems and social competence: Mediation through children's regulation.

The relations between mothers' expressed positive and negative emotion and 55–79-month-olds' (76% European American) regulation, social competence, and adjustment were examined. Structural equation modeling was used to test the plausibility of the hypothesis that the effects of maternal expression of emotion on children's adjustment and social competence are mediated through children's dispositional regulation. Mothers' expressed emotions were assessed during interactions with their children and with maternal reports of emotions expressed in the family. Children's regulation, externalizing and internalizing problems, and social competence were rated by parents and teachers, and children's persistence was surreptitiously observed. There were unique effects of positive and negative maternal expressed emotion on children's regulation, and the relations of maternal expressed emotion to children's externalizing problem behaviors and social competence were mediated through children's regulation. Alternative models of causation were tested; a child-directed model in which maternal expressivity mediated the effects of child regulation on child outcomes did not fit the data as well. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Is familial hyperparathyroidism a unique disease?

BACKGROUND: Familial hyperparathyroidism is a rare condition reported to behave more aggressively than sporadic hyperparathyroidism. METHODS: A retrospective (1975 to 1995) analysis was performed on 30 such patients. All patients had at least one first-degree relative with surgically treated hyperparathyroidism and no personal or family history of multiple endocrine neoplasia. RESULTS: There were 19 women and 11 men with a mean age of 39 years (range, 13 to 78 years). Fourteen patients (47%) had nephrolithiasis. The mean serum calcium level was 11.6 mg/dl (range, 10.5 to 15.3 mg/dl). Twenty-three primary and 15 repeat explorations (eight recurrent and seven persistent disease) were performed during the study period. Follow-up was obtained on all patients and ranged from 1 to 21 years (mean, 12 years). At the conclusion of the study, hypercalcemia (five recurrent and one persistent) was present in six patients (20%). CONCLUSIONS: Familial hyperparathyroidism is a distinct and unique entity. Patients are diagnosed at a young age and have a high incidence of nephrolithiasis. Long-term follow-up is mandatory because of the high incidence of both recurrent and persistent hyperparathyroidism. Surgical treatment should include subtotal parathyroidectomy and routine transcervical thymectomy performed in centers with experience in the management of multiple-gland parathyroid disease.     

Immunohistochemical localization of p21(WAF1/CIP1) in normal, hyperplastic, and neoplastic uterine tissues

Assuming that the chemical reactions used to synthesize a combinatorial library member are successful, then knowledge of the specific reaction sequence is equivalent to knowing the member's chemical identity. Because the determination of chemical identity is typically not automatable and requires a substantial amount of material, schemes that encode a member's reaction history onto the reaction platform are of value. The primary benefits of encoding are relational nomenclature (all methods) and automated handling (some methods). Encoding methods evaluated to date are spatial, graphical, chemical, spectrometric, electronic, and physical.     

Chest radiographic data acquisition and quality assurance in multicenter studies

Dorsal fusion with the internal fixator has become the standard treatment of instabilities and deformities of the thoracolumbar spine. With our new device, the modular spine fixator (MSF), which has been specially designed for short-distance instrumentations, we have increasingly been treating unstable injuries of the thoracolumbar spine by one-level stabilization. Prerequisite is an accurate evaluation of the indication, including CT and MRI to assess the involvement of the intervertebral disc and the ligamental structures. The operative technique differs in some details from the procedure in more-multi-level instrumentations, especially concerning the application of the pedicle screws. The instrumentation is always combined with posterior allogenic bone grafting. Since the beginning of 1993 we also perform anterior autogenic transpedicular bone grafting. Between January 1991 and July 1995, 57 one-level stabilizations with the MSF were performed. Of the 57 patients operated on 39, 27 men and 12 women, with an average age of 41 years, have had a clinical and radiographic follow-up examination so far, on average, 27 months after the accident. Seventeen patients were completely free of pain and 17 patients (were only) sensitive to weather changes or had minor pain during great physical stress. Five patients had pain even during slight physical stress or at rest. The preoperatively measured Cobb angle was 15.1 degrees on average, after the operation 5.2 degrees, and at the time of the follow-up examination amounted to 8.1 degrees. The patients' range of motion was normal. Only five minor complications have been seen. No implant fatigue failure has been noted in this series. We derive from these results that, for correct indications, one-level stabilization can be performed successfully and should be firmly established in the operative treatment of unstable fractures of the thoracolumbar spine.     

Cortical input to the basal forebrain

The arborization pattern and postsynaptic targets of corticofugal axons in basal forebrain areas have been studied by the combination of anatomical tract-tracing and pre- and postembedding immunocytochemistry. The anterograde neuronal tracer Phaseolus vulgaris leucoagglutinin was iontophoretically delivered into different neocortical (frontal, parietal, occipital), allocortical (piriform) and mesocortical (insular, prefrontal) areas in rats. To identify the transmitter phenotype in pre- or postsynaptic elements, the tracer staining was combined with immunolabeling for either glutamate or GABA, or with immunolabeling for choline acetyltransferase or parvalbumin. Tracer injections into medial and ventral prefrontal areas gave rise to dense terminal arborizations in extended basal forebrain areas, particularly in the horizontal limb of the diagonal band and the region ventral to it. Terminals were also found to a lesser extent in the ventral part of the substantia innominata and in ventral pallidal areas adjoining ventral striatal territories. Similarly, labeled fibers from the piriform and insular cortices were found to reach lateral and ventral parts of the substantia innominata, where terminal varicosities were evident. In contrast, descending fibers from neocortical areas were smooth, devoid of terminal varicosities, and restricted to the myelinated fascicles of the internal capsule en route to more caudal targets. Ultrastructural studies obtained indicated that corticofugal axon terminals in the basal forebrain areas form synaptic contact primarily with dendritic spines or small dendritic branches (89%); the remaining axon terminals established synapses with dendritic shafts. All tracer labeled axon terminals were immunonegative for GABA, and in the cases investigated, were found to contain glutamate immunoreactivity. In material stained for the anterograde tracer and choline acetyltransferase, a total of 63 Phaseolus vulgaris leucoagglutinin varicosities closely associated with cholinergic profiles were selected for electron microscopic analysis. From this material, 37 varicosities were identified as establishing asymmetric synaptic contacts with neurons that were immunonegative for choline acetyltransferase, including spines and small dendrites (87%) or dendritic shafts (13%). Unequivocal evidence for synaptic interactions between tracer labeled terminals and cholinergic profiles could not be obtained in the remaining cases. From material stained for the anterograde tracer and parvalbumin, 40% of the labeled terminals investigated were found to establish synapses with parvalbumin-positive elements; these contacts were on dendritic shafts and were of the asymmetrical type. The present data suggest that corticofugal axons innervate forebrain neurons that are primarily inhibitory and non-cholinergic; local forebrain axonal arborizations of these cells may represent a mechanism by which prefrontal cortical areas control basal forebrain cholinergic neurons outside the traditional boundaries of pallidal areas.     

The effects of dexamethasone immunosuppression on turkey osteomyelitis complex in an experimental Escherichia coli respiratory infection

The results of a field trial conducted in Latin America with two indirect enzyme-linked immunosorbent assays (ELISAs) and two competitive ELISAs (CELISAs) for the detection of bovine antibody to Brucella abortus are reported. One of the CELISA formats performed most accurately. The percentage of positive reactions in the CELISA relative to the selected positive rose bengal agglutination test (RBT) and complement fixation test (CFT) results was 97.47%, the percentage of negatives relative to the selected negative RBT and CFT results for unexposed cattle was 98.32%, and the percentage of negatives in cattle vaccinated with B. abortus 19 was 96.51%. The same assay format under Canadian conditions had an actual sensitivity of 100%, a specificity of 99.90% in nonvaccinates, and a specificity of 97.7% in a strain 19-vaccinated population. Overall, the CELISA performed as expected and the results were not dissimilar from the results obtained in the Canadian study. This provided further evidence that this CELISA can in many instances differentiate infected cattle from those that are vaccinated or infected with a cross-reacting organism while still giving very few false-positive or false-negative results.     

Is access to medical care associated with receipt of HIV testing and counselling?

Lack of timely HIV testing leads to missed prevention opportunities and poor prevention counselling may be related to further disease spread. We examined the association of self-reported access to medical care with receiving HIV testing and preventive counselling services among a sample of patients with HIV disease prior to hospitalization. We conducted a cross-sectional interview of 217 Los Angeles patients hospitalized with HIV-related illness between 1992 and 1993 and abstracted clinical data from the medical record. Eighty-four per cent of patients received HIV testing prior to hospitalization, but only 33% received preventive counselling services. Only 48% of all patients rated outpatient medical care as somewhat or very easy to obtain. Controlling for severity of illness, better access to outpatient medical care (OR = 1.48; 95% CI = 1.02-2.15), having a regular source of care (OR = 3.40; 95% CI = 1.29-8.97) and non-homosexual mode of HIV transmission (OR = 0.31; 0.12-0.83) were associated with receiving HIV testing services prior to hospitalization. Having a regular source of care (OR = 3.55; 95% CI = 1.37-9.22), being VA (Veterans' Administration) insured (OR = 6.16; 1.46-26.05), older age (OR = 0.95; 95% CI = 0.90-0.99) and having a CD4 count between 101-200 (OR = 0.19; 95% CI = 0.06-0.63) were associated with receiving HIV counselling. Limited self-reported access to medical care is associated with fewer patients receiving HIV testing and counselling. Improving timeliness of HIV testing may require removing the barriers to medical care.     

Determination of phosphine residues in whole grains and soybeans by ion chromatography via conversion to phosphate

An ion chromatographic (IC) method was developed for determining phosphine (PH3) in whole grains (barley, corn, oats, rice, rye, and wheat) and soybeans. The method converts phosphine to phosphate (i.e., orthophosphate) and isolates the phosphate by IC with eluent-suppressed conductivity detection. Recoveries of unbound phosphine by the method were similar to those obtained by an established colorimetric method for 7 different products fortified at 3 levels. Mean recoveries were low (i.e., 30-60%) and varied with product type and level of fortification. Recoveries of PH3 from previously fumigated products fortified with aluminum phosphide ranged from 19.0% for barley fortified at 0.734 ppm to 88.3% for corn fortified at 1.691 ppm. Precision data from 3 products based on replicate analyses (n = 4 or 5) gave relative standard deviations of 1.78-4.66% for mean laboratory-fumigated PH3 levels of 0.679-1.309 ppm. Estimated limits of detection (LOD) and quantitation (LOQ) for PH3 were 0.010 microgram/g (10 ppb) and 0.0275 microgram/g (27.5 ppb) at signal-to-noise ratios (S/N) of 4:1 and 10:1, respectively. These values were also determined for a nonchemically suppressed IC system with LOD of 0.02 microgram/g (20 ppb) and LOQ of 0.055 microgram/g (55 ppb) at S/N of 4:1 and 10:1, respectively. Phosphate response was linear over the concentration range equivalent to 0.30-10.0 micrograms P/mL, with a mean correlation coefficient of 0.9988 based on replicate standard curves. The relationship of product composition to recovery from various products was also examined.