Relationships among alterations in renal membrane sodium transport, renin and aminopeptidase M activities in genetic hypertension

Presentation of 31 patients with suspected diagnosis of upper urothelium tumour seen between 1986 and 1991. In agreement with our study protocol and the endourological treatment followed in this type of tumours, there were eight false positive, which were excluded. Five cases were treated by retrograde ureterorenoscopy while in the remaining 18 cases the anterograde percutaneous approach was used. A review of both the aspects of endoeurological treatment and the evolution of these patients during that period is included.     

Regulation of messenger ribonucleic acid expression for gluconeogenic enzymes during glucagon infusions into lactating cows.

The effects of glucagon infusions on expression of mRNA for enzymes that regulate gluconeogenesis were studied in lactating cows. Normal cows and cows with fatty liver that were susceptible to ketosis were assigned to either glucagon-treated or control groups. Glucagon at 0 or 10 mg/d was infused for 14 d beginning at d 21 postpartum. In normal cows, glucagon infusions increased concentrations of both plasma glucagon and glucose, which caused plasma insulin to increase. Consequently, hepatic phosphoenolpyruvate carboxykinase mRNA decreased during wk 1 of glucagon infusions. Glucagon infusions into cows with fatty liver also increased plasma glucagon and glucose, but concentrations of plasma insulin and hepatic phosphoenolpyruvate carboxykinase mRNA did not change. More phosphoenolpyruvate carboxykinase mRNA was present in the livers of cows with fatty liver than in livers of normal cows. In a follow-up experiment with midlactation cows, 3.5-h infusions of glucagon at 14 mg/d increased plasma glucose and insulin and decreased plasma nonesterified fatty acids and hepatic glycogen. Hepatic phosphoenolpyruvate carboxykinase mRNA was decreased 41%, pyruvate carboxylase mRNA was increased 50%, but fructose-1,6-bisphosphatase mRNA did not change. We conclude that the expression of the hepatic phosphoenolpyruvate carboxykinase gene in normal cows is inhibited by insulin to balance elevated carbohydrate status during glucagon infusions; however, inhibited expression of hepatic phosphoenolpyruvate carboxykinase mRNA probably is not involved in the pathogenesis of lactation ketosis.     

Mutations of the p53 tumor suppressor gene occur infrequently in Wilms' tumor

Mutations of the p53 tumor suppressor gene occur frequently in a variety of adult-onset tumors, including colon, breast, lung, and brain, yet are infrequently identified in pediatric malignancies. Wilms' tumor, a common solid tumor of childhood, can be associated with mutations of the WT1 gene. Alterations of the p53 gene have been shown to modulate the ability of WT1 to transactivate its targets. Although positive p53 immunostaining has been demonstrated in Wilms' tumors, the correlation to p53 gene mutations is not clear. We examined Wilms' tumor samples for p53 mutations utilizing polymerase chain reaction-single-strand conformation polymorphism analysis and single-strand DNA sequencing. Mutations in the coding region of the p53 gene were demonstrated in 2 of 21 (9.5%) Wilms' tumors. Each mutation yielded a substitution of amino acid residues. One mutation was located in exon 6 and the other in exon 7. Both mutations were found in tumors from patients with advanced stage disease. Focal anaplasia was demonstrated in one of these tumors. Our data suggest that although p53 mutations occur infrequently in Wilms' tumor, they may be associated with advanced disease.     

Contrast gain control in psychophysical contrast discrimination

Contrast masking may in part reflect the operation of contrast gain control mechanisms in the visual system. Four experiments were conducted in order to examine contrast discrimination under conditions in which the base contrast was interrupted with various maskers. Interrupting the base contrast grating at 8 Hz--with a uniform field, with a randomly phase-shifted version of the same grating, or with a higher contrast version of the same grating--interfered with contrast discrimination. These effects occurred only when the background contrast was above its own threshold. These results may be explained by assuming that the networks responsible for contrast gain control operate by temporally averaging contrast over a period greater than 62.5 msec. When this time-averaged contrast is different from the base contrast, contrast discrimination suffers.     

A localized double-quantum filter for the in vivo detection of brain glucose

OBJECTIVES: Despite decreasing infant mortality in North Carolina, the gap between African Americans and Whites persists. This study examined how racial differences in infant mortality vary by maternal education. METHODS: Data came from Linked Birth and Infant Death files for 1988 through 1993. Multiple logistic regression models adjusted for confounders. RESULTS: Infant mortality risk ratios comparing African Americans and Whites increased with higher levels of maternal education. Education beyond high school reduced risk of infant mortality by 20% among Whites but had little effect among African Americans. CONCLUSIONS: Higher education magnifies racial differences in infant mortality on a multiplicative scale. Possible reasons include greater stress, fewer economic resources, and poorer quality of prenatal care among African Americans.     

Diabetics with coronary disease have a prevalence of asymptomatic ischemia during exercise treadmill testing and ambulatory ischemia monitoring similar to that of nondiabetic patients. An ACIP database study. ACIP Investigators. Asymptomatic Cardiac Ischemia Pilot Investigators

BACKGROUND: There are conflicting data as to whether diabetics have a higher prevalence of asymptomatic ST-segment depression during exercise treadmill testing (ETT) and ambulatory ECG (AECG) monitoring. This study was conducted to determine whether diabetic patients with coronary disease enrolled in the Asymptomatic Cardiac Ischemia Pilot (ACIP) have more episodes of asymptomatic ischemia during ETT and 48-hour AECG monitoring than nondiabetic patients and to compare differences in angiographic variables and the magnitude of ischemia as measured by standard ETT and AECG criteria. METHODS AND RESULTS: Angiographic variables and the prevalence and magnitude of ischemia during the qualifying ETT and 48-hour AECG were compared by the presence and absence of diabetes mellitus in 558 randomized ACIP patients. Seventy-seven patients had a history of diabetes and were taking oral hypoglycemics or insulin (diabetic group); 481 patients did not meet these criteria (nondiabetic group). Multivessel disease (87% versus 74%, P = .01) was more frequent in the diabetic group. The percentages of patients without angina during the ETT were similar in the diabetic and nondiabetic groups (36% and 39%, respectively). Time to onset of > or = 1-mm ST-segment depression and time to onset of angina were similar in both groups. The percentages of patients with only asymptomatic ST-segment depression during the 48-hour AECG were similar in the diabetic and nondiabetic groups (94% versus 88%, respectively). However, total ischemic time per 24 hours (15.0 +/- 21.4 versus 23.6 +/- 31.1 minutes, P = .02), ischemic time per episode (6.3 +/- 4.6 versus 9.0 +/- 8.7 minutes, P < .01), and the maximum depth of ST-segment depression tended to be less in the diabetic group. CONCLUSIONS: Patients enrolled in ACIP were selected on the basis of an abnormal ETT and 48-hour AECG and ability to undergo coronary revascularization. When patients with diabetes mellitus were compared with those without diabetes, there was a similar prevalence of asymptomatic ischemia during ETT and 48-hour AECG monitoring. Despite more extensive and diffuse coronary disease, diabetic ACIP patients tended to have less measurable ischemia during the 48-hour AECG.     

Resources for alternative and complementary cancer therapies

Seventeen patients with persistent chronic hand eczema were treated with topical 0.1% 8-methoxypsoralen and UVA (PUVA) for 8 weeks. Significant improvement was achieved in 5 cases (29%), moderate improvement in 9 (53%), and little improvement in 3 (18%). The mean number of PUVA treatments was 22.2, and the mean total UVA dose was 63.5 J/cm2. There was no association between clinical response and duration of hand eczema, positive patch test reaction, or atopic status. Since topical PUVA has no risk of systemic side effects, it should be considered as an alternative treatment for patients with chronic hand eczema who are resistant to other topical medications.     

二甲基二氯硅烷水解中FC－95定量分析研究

本文用原子吸收光谱对恒沸酸中微量表面活性剂ＦＣ－９５进行了定量分析，并叙述了实验方法、样品处理方法等。     

Evaluation of agonist-antagonist properties of nitrogen mustard and cyano derivatives of delta 8-tetrahydrocannabinol

delta 8-Tetrahydrocannabinol (delta 8-THC) is a naturally occurring cannabinoid with a characteristic pharmacological profile of in vivo effects. Previous studies have shown that modification of the structure of delta 8-THC by inclusion of a nitrogen-containing functional group alters this profile and may alkylate the cannabinoid receptor, similar to the manner in which beta-funaltrexamine (beta-FNA) alkylates the micro-opioid receptor. Two novel analogs of delta 8-THC were synthesized: a nitrogen mustard analog with a dimethylheptyl side chain (NM-delta 8-THC) and a cyano analog with a dimethylpentyl side chain (CY-delta 8-THC). Both analogs showed high affinity for brain cannabinoid receptors and when administered acutely, produced characteristic delta 9-THC-like effects in mice, including locomotor suppression, hypothermia, antinociception and catalepsy. CY-delta 8-THC shared discriminative stimulus effects with CP 55,940; for NM-delta 8-THC, these effects also occurred, but were delayed. Although both compounds attenuated the effects of delta 9-THC in the mouse behavioral tests, evaluation of potential antagonist effects of these compounds was complicated by the fact that two injections of delta 9-THC produced similar results, suggesting that acute tolerance or desensitization might account for the observations. NM-delta 8-THC, but not CY-delta 8-THC, attenuated the discriminative stimulus effects of CP 55,940 in rats several days following injection. Hence, addition of a nitrogen-containing functional group to a traditional cannabinoid structure does not eliminate agonist effects and may produce delayed attenuation of cannabinoid-induced pharmacological effects.     

使用无Q开关脉冲激光器拍摄全息肖像的研究

通常认为拍摄脉冲全息肖像必须使用带有Ｑ开关运转模式的脉冲激光器，否则是不可能拍摄成功的。本文介绍了我们使用无Ｑ开关的脉冲激光器研制出高质量脉冲质量肖像的工作，以及在此情况下应注意的若干问题。