Quasi-analytical static solution of the boxed microstrip lineembedded in a layered medium

A quasi-analytical method to carry out the quasi-TEM study of a microstrip line embedded in a general layered substrate with rectangular enclosure is presented. Electric walls, magnetic walls, and periodic boundary conditions are considered. The analysis is based on the spectral-domain formulation and the use of a proper expansion of the free charge distribution (Chebyshev polynomials with edge condition). Two different approaches are proposed to speed up the evaluation of the spectral series in such a way that only a few spectral terms must be retained in the numerical computations of the mentioned series. The propagation parameters and the charge distribution are obtained with extreme accuracy in fractions of one second on a personal computer     

Comparison of the cumulative probability of pregnancy after in vitro fertilization-embryo transfer by infertility factor and age

OBJECTIVE: To compare the cumulative probability of pregnancy after multiple IVF cycles by age and cause of infertility. DESIGN: A prospective study was done in which patients were followed from the time they registered for their first IVF cycle until they achieved a clinical pregnancy, withdrew from treatment, or study was terminated. PATIENTS, SETTING, TREATMENTS: Infertile women undergoing IVF-ET at the Cooper Institute for In Vitro Fertilization were enrolled in this study if the luteal phase leuprolide acetate (LA) and hMG controlled ovarian hyperstimulation (COH) regimen was used. MAIN OUTCOME MEASURES: Clinical pregnancy, as determined by a positive beta-hCG level and ultrasonographic confirmation of a gestational sac, and delivery rates based on number of women with live births were compared by infertility factor and age. RESULTS: The 3-month cumulative probability of pregnancy based on life table analysis was 33% in women with tubal factor who were < or = 35 years of age, 25% in women with tubal factor who were > 35 years of age, 30% for women with multiple factors who were < or = 35 years of age, and 14% for women with multiple factors who were > 35 years of age. The rate for the older women with multiple factors was significantly lower than that for the other groups. The delivery rates were lower for the women with multiple factors than for women under 35 with tubal factor only. CONCLUSIONS: There is a significant effect of age and infertility factor on pregnancy and delivery rates. Physicians should consider these factors in evaluating their patients' prospects for success in IVF-ET.     

Single lung transplantation in patients with systemic disease

OBJECTIVE: To report functional results and survival in patients undergoing single lung transplantation (SLT) for pulmonary involvement associated with systemic disease or prior malignancy, criteria traditionally considered contraindications to SLT. DESIGN: Case series. SETTING: The University of Texas Health Science Center at San Antonio. PATIENTS: Nine patients who have undergone SLT for end-stage lung disease: four patients with sarcoidosis; two patients with limited scleroderma; and three patients with prior malignancies (two with prior lymphoma and bleomycin-induced pulmonary fibrosis and one who received two bone marrow transplants for acute lymphocytic leukemia and subsequently developed chemotherapy-induced pulmonary fibrosis). MEASUREMENTS: Pulmonary function testing, exercise oximetry, quantitative ventilation-perfusion lung scanning. Actuarial survival. RESULTS: All patients had marked improvement in pulmonary function, exercise oximetry, and quantitative ventilation perfusion to the SLT. One patient with scleroderma died 90 days postoperatively from Pseudomonas pneumonia with a sepsis syndrome. One patient with sarcoidosis died 150 days postoperatively from disseminated aspergillosis. At autopsy, there was no evidence of recurrent fibrosis or sarcoidosis in the transplanted lungs in either of these two patients. The seven surviving patients have returned to work or school and are conducting all activities of daily living without pulmonary disability. The 1- and 2-year actuarial survival rates in these nine patients is 68.6 percent as compared with the 1- and 2-year actuarial survival rates of 66.3 percent and 55.8 percent in the remainder of our SLT group as a whole (n = 49). Despite pharmacologic immunosuppression, there is no evidence of recurrent malignancy in the 3 patients with prior malignancies. CONCLUSIONS: We conclude that carefully selected patients with end-stage lung involvement related to systemic disease or chemotherapy-induced fibrosis may benefit from SLT.     

Full blockade of intestinal P-glycoprotein and extensive inhibition of blood-brain barrier P-glycoprotein by oral treatment of mice with PSC833

Mice lacking mdr1-type P-glycoproteins (mdr1a/1b [-/-] mice) display large changes in the pharmacokinetics of digoxin and other drugs. Using the kinetics of digoxin in mdr1a/1b (-/-) mice as a model representing a complete block of P-glycoprotein activity, we investigated the activity and specificity of the reversal agent SDZ PSC833 in inhibiting mdr1-type P-glycoproteins in vivo. Oral PSC833 was coadministered with intravenous [3H]digoxin to wild-type and mdr1a/1b (-/-) mice. The direct excretion of [3H]digoxin mediated by P-glycoprotein in the intestinal mucosa of wild-type mice was abolished by administration of PSC833. Hepatobiliary excretion of [3H]digoxin was markedly decreased in both wild-type and mdr1a/1b (-/-) mice by PSC833, the latter effect indicating that in vivo, PSC833 inhibits not only mdr1-type P-glycoproteins, but also other drug transporters. Upon coadministration of PSC833, brain levels of [3H]digoxin in wild-type mice showed a large increase, approaching (but not equaling) the levels found in brains of PSC833-treated mdr1a/1b (-/-) mice. Thus, orally administered PSC833 can inhibit blood-brain barrier P-glycoprotein extensively, and intestinal P-glycoprotein completely. These profound pharmacokinetic effects of PSC833 treatment imply potential risks, but also promising pharmacological applications of the use of effective reversal agents.     

Anticoagulant rodenticide poisoning in dogs in The Netherlands

The occurrence, the diagnosis, and the treatment of anticoagulant rodenticide poisoning in dogs in the Netherlands was evaluated by a survey among Dutch veterinarians carried out by the National Poisons Control Center (NPCC). The survey included information on 54 dogs, 32 being treated by veterinarians who consulted the NPCC and 22 that were admitted to the Utrecht University Clinic for Companion Animals (UUCCA). The poisons that were suspected were brodifacoum (n = 19), bromadiolone (n = 14), difenacoum (n = 8), difethialone (n = 6) and chlorophacinone (n = 1). In 6 dogs the identity of the poison was unknown. Of 31 dogs with hemorrhages, 2 died shortly after presentation to practitioners and 2 died shortly after admission to the UUCCA. Signs of bleeding occurred especially in poisoning by brodifacoum (n = 16). In all but one of the dogs without hemorrhages, the intake of poison had taken place within 24 hours before presentation. The method of treatment varied, with the induction of vomiting and the use of vitamin K mentioned most. The choice of therapy was determined by the length of time after intake of the poison, the clinical signs and whether or not an anticoagulant toxicosis was suspected at the time of the initial examination. These findings provide the basis for discussion of several aspects of diagnosis and treatment.     

Regional blood flow during pulsatile cardiopulmonary bypass and after circulatory arrest in an infant model

BACKGROUND: Pulsatile perfusion systems have been proposed as a means of improving end-organ perfusion during and after cardiopulmonary bypass. Few attempts have been made to study this issue in an infant model. METHODS: Neonatal piglets were subjected to nonpulsatile (n = 6) or pulsatile (n = 7) cardiopulmonary bypass and 60 minutes of circulatory arrest. Cerebral, renal, and myocardial blood flow measurements were obtained at baseline, on bypass before and after circulatory arrest, and after bypass. RESULTS: Cerebral blood flow did not differ between groups at any time and was diminished equally in both groups after circulatory arrest. Renal blood flow was diminished in both groups during bypass but was significantly better in the pulsatile group than in the nonpulsatile group prior to, but not after, circulatory arrest. Myocardial blood flow was maintained at or above baseline in the pulsatile group throughout the study, but in the nonpulsatile group, it was significantly lower than baseline during CPB prior to circulatory arrest and lower compared with baseline and with the pulsatile group 60 minutes after CPB. CONCLUSIONS: Pulsatile bypass does not improve recovery of cerebral blood flow after circulatory arrest, may improve renal perfusion during bypass but does not improve its recovery after ischemia, and may have beneficial effects on myocardial blood flow during bypass and after ischemia compared with nonpulsatile bypass in this infant model.     

Value of Doppler color ultrasonography in diagnosis of arterial occlusive disease of the lower extremity. A direct comparison with percutaneous angiography

A Direct Comparison with Percutaneous Angiography: AIM: To compare colour-coded Doppler sonography (CCDS) with conventional angiography in severe occlusive vascular disease of the lower limb. METHODS: In 55 patients 1141 vessel segments were evaluated, 700 of them with atheromatous plaques, 270 with stenoses, 208 with occlusions and 6 with aneurysms. RESULTS: Deeper-seated vessels such as the abdominal aorta, the pelvic arteries, the superficial femoral artery at the level of the adductor canal and parts of the lower leg arteries are less accessible for direct CCDS. Many pathological changes however can be diagnosed indirectly by changes in the spectral wave form distal to the lesion. In superficial vascular segments (the common femoral artery, the profunda femoris artery, the superficial femoral artery above the adductor canal and the popliteal artery) image quality was excellent, more pathological changes were found, and the degree of stenosis was better estimated in comparison to angiography. CONCLUSION: The value of CCDS in patients with intermittent claudication is limited to those who have been examined with angiography e.g. before angioplasty, to follow-up examinations after vascular dilatation or surgery and to supplementary visualisation after angiography especially in readily accessible (superficial) vascular segments.     

Associations of serum and dietary magnesium with cardiovascular disease, hypertension, diabetes, insulin, and carotid arterial wall thickness: the ARIC study. Atherosclerosis Risk in Communities Study

The objective of this study was to examine the relationships of serum and dietary magnesium (Mg) with prevalent cardiovascular disease (CVD), hypertension, diabetes mellitus, fasting insulin, and average carotid intimal-medial wall thickness measured by B-mode ultrasound. A cross-sectional design was used. The setting was the Atherosclerosis Risk in Communities (ARIC) Study in four US communities. A total of 15,248 participants took part, male and female, black and white, aged 45-64 years. Fasting serum Mg, lipids, fasting glucose and insulin were measured; as was usual dietary intake by food frequency questionnaire and carotid intima-media thickness by standardized B-mode ultrasound methods. The results showed that serum Mg levels and dietary Mg intake were both lower in blacks than whites. Mean serum Mg levels were significantly lower in participants with prevalent CVD, hypertension, and diabetes than in those free of these diseases. In participants without CVD, serum Mg levels were also inversely associated with fasting serum insulin, glucose, systolic blood pressure and smoking. Dietary Mg intake was inversely associated with fasting serum insulin, plasma high density lipoprotein-cholesterol, systolic and diastolic blood pressure. Adjusted for age, race, body mass index, smoking, hypertension, Low density lipoprotein-cholesterol, and field center, mean carotid wall thickness increased in women by 0.0118 mm (p = 0.006) in diuretic users and 0.0048 mm (p = 0.017) in nonusers for each 0.1 mmol/l decrease in serum Mg level; the multivariate association in men was not significant. In conclusion, low serum and dietary Mg may be related to the etiologies of CVD, hypertension, diabetes, and atherosclerosis.     

Analgesic, respiratory and heart rate effects of cannabinoid and opioid agonists in rhesus monkeys: antagonist effects of SR 141716A

This study characterized the antinociceptive, respiratory and heart rate effects of the cannabinoid receptor agonists Delta-9-tetrahydrocannabinol (Delta-9-THC) and WIN 55212 ((R)-(+)-2, 3-dihydro-5-methyl-3-[(4-morpholinyl)methyl]pyrol-[1,2,3-de]-1, 4-benzoxazin-6-yl)(1-naphtalenyl)methanone monomethanesulfonate), N-arachidonyl ethanolamide (anandamide) and the mu and kappa opioid receptor agonists heroin and U69593, alone and in conjunction with a cannabinoid receptor antagonist, SR 141716A [N-(piperidin-1-1-yl)-5-(4-chlorophenyl)-1(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide hydrochloride] and an opioid receptor antagonist, quadazocine, in rhesus monkeys (Macaca mulatta). Using 12 adult rhesus monkeys, latencies to remove the tail from a 50 degrees C water bath, respiration in 5% CO2 and heart rate were measured. When administered alone, SR 141716A (1.8, 5.6 mg/kg i.m.) did not alter nociception, respiration or heart rate. Delta-9-THC (0.1-10 mg/kg i.m.) and WIN 55212 (0.1-10 mg/kg i.m.) dose-dependently increased antinociception and dose-dependently decreased respiratory minute and tidal volumes and heart rate. These antinociceptive, respiratory and heart rate effects were reversed by SR 141716A but not by the opioid antagonist quadazocine (1 mg/kg i.m.). Anandamide (10 mg/kg i.m.) also produced antinociception. Heroin (0.01-10 mg/kg i.m.) and U69593 (0.01-3.2 mg/kg i.m.) also dose-dependently increased antinociception and decreased respiratory and heart rate measures; these effects were antagonized by quadazocine but not by SR 141716A. These results demonstrate selective and reversible antagonism of cannabinoid behavioral effects by SR 141716A in rhesus monkeys.