Range-gated pulsed Doppler ultrasonographic evaluation of carotid arterial blood flow in small preterm infants with patent ductus arteriosus

Range-gated pulsed Doppler (RGPD) ultrasonography was utilized to study the effect of a patent ductus arteriosus (PDA) on carotid arterial blood flow in small preterm infants. Carotid arterial flow velocity studies were performed on 23 preterm infants, sampling right and left carotid arteries. Studies on seven infants after PDA ligation and on seven who developed no evidence of PDA were used as controls. A strong relationship was demonstrated between diastolic reversal in the carotid arteries and PDA. The results of this study indicate that the RGPD flow velocity curve from the carotid artery is more sensitive than M-mode echocardiography or clinical examination in detecting PDA, and that PDA in small preterm infants is associated with a distinct abnormality in the carotid arterial flow pattern.     

Relationship between pressure passivity and subependymal/intraventricular hemorrhage as assessed by pulsed Doppler ultrasound

A prospective study was undertaken using a range-gated, pulsed Doppler velocimeter to study flowpressure relationships in the anterior cerebral artery. Serial velocity and pressure studies were performed with each infant serving as his or her own control. The hypothesis tested was that ill preterm infants sustaining subependymal/intraventricular hemorrhage would have absent autoregulation. The hypothesis has been tested in 88 studies on 32 infants. Of 32 infants studied, 15 were judged to be pressure passive; nine of these children bled. The other 17 infants were not pressure passive; eight of these children bled (P greater than .05). From these studies, it may be concluded that the pressure passive state is not the final common link in the genesis of subependymal/intravertricular hemorrhage. Pulsed Doppler ultrasound may provide an extremely useful noninvasive technique for studying both the arterial and venous sides of the cerebral circulation.     

Steady-state bioavailability of two clorazepate dipotassium dosage forms.

A specially designed tablet dosage form of the benzodiazepine clorazepate dipotassium (Tranxene) was developed for once-a-day administration. The drug was administered at a dose of 22.5 mg as (1) the tablet, (2) three 7.5 mg capsules, or (3) one 7.5-mg capsule given every 6 hours. Peak serum levels from the tablet were intermediate between those of the single- and divided-dose capsule regimens. The desired decrease in magnitude of peak levels was obtained without affecting the extent of absorption. Pharmacokinetic analysis of the data according to a two-compartment open model with first-order absorption indicated that the serum half-life (t0.5beta) of nordiazepam, the major biotransformation product present in serum, was about 48 hours and served as a basis for the design of a multiple-dose steady-state study. Multiple-dose administration of the tablet and divided-capsule regimen to two groups of subjects for ten days indicated each dosage form yielded similar minimum steady-state serum levels of about 0.6 micrograms/ml which plateaued following seven days of drug administration. The dosage forms were crossed over between the groups on day 11 and administered for an additional four days. The minimum serum levels obtained with the tablet and capsule were not statistically different. Additionally, the peak serum level and area under the curve (pi=24 hours) at steady state were equivalent between the dosage forms. Good agreement was obtained between model-predicted and observed serum levels during multiple-dose administration for both the tablet and capsule regimens. The serum half-life of nordiazepam following 14 days of clorazepate dipotassium administration was similar to that found after a single dose. These results indicate that a single daily dose of drug as the tablet produced serum levels equivalent to a divided-capsule regimen.     

Association of Total Cholesterol/High-Density Lipoprotein Cholesterol Ratio With Proximal Coronary Atherosclerosis Detected by Multislice Computed Tomography

The authors assessed the association between an elevated total cholesterol to high-density lipoprotein cholesterol (TC/HDL-C) ratio (≥4) and proximal coronary artery disease (CAD), as observed on multislice computed tomography. Coronary multislice computed tomographic angiography (96% on 40- or 64-slice) was performed in 295 individuals (39% women; mean age, 54±13 years) without documented CAD who were referred for coronary evaluation. Significant CAD was defined as ≥50% stenosis in the left main, proximal left anterior descending, or ≥2 epicardial vessels. Proximal plaque was defined as presence of any plaque in left main or proximal left anterior descending vessels. Individuals with an elevated TC/HDL-C ratio vs those without had a higher prevalence of proximal plaque (62% vs 48%, P =.04) and significant CAD (19% vs 9%, P =.009). On multivariate logistic regression analysis, only age, sex, and TC/HDL-C ratio ≥4 were associated with significant CAD and proximal plaque.     

A lyophilized red grape pomace containing proanthocyanidin-rich dietary fiber induces genetic and metabolic alterations in colon mucosa of female C57BL/6J mice

Diet plays a decisive role in promoting or preventing colon cancer. However, the specific effects of some nutrients remain unclear. The capacity of fruit and vegetables to prevent cancer has been associated with their fiber and antioxidant composition. We investigated whether consumption of a lyophilized red grape pomace containing proanthocyanidin-rich dietary fiber (grape antioxidant dietary fiber, GADF) by female C57BL/6J mice would affect the serum metabolic profile or colon mucosa gene expression using NMR techniques and DNA microarray, respectively. The mice were randomly assigned to 2 groups that for 2 wk consumed a standard rodent diet and were gavaged with 100 mg/kg body weight GADF suspended in water or an equivalent volume of plain tap water (10 mL/kg body weight). The amount of fiber supplemented was calculated to equal the current recommended daily levels of fiber consumption for humans. The inclusion of dietary GADF induced alterations in the expression of tumor suppressor genes and proto-oncogenes as well as the modulation of genes from pathways, including lipid biosynthesis, energy metabolism, cell cycle, and apoptosis. Overexpression of enzymes pertaining to the xenobiotic detoxifying system and endogenous antioxidant cell defenses was also observed. In summary, the genetic and metabolic profiles induced by GADF were consistent with the preventive effects of fiber and polyphenols. On the basis of these observations, we propose that GADF may contribute to reducing the risk of colon cancer.     

A systematic review of the relationship between psychological disorders or substance use and self-reported cognitive failures

Introduction: Cognitive failures are errors in normal everyday functioning. Individuals with psychological disorders may possess heightened vulnerability. We sought to review the literature on cognitive failures in psychological disorders to determine the nature of this association, and whether failures relate to neuropsychological performance. We also examine the relationship between cognitive failures and substance use since it is relevant to everyday cognition and co-occurs in many psychological disorders.

Methods: We conducted a systematic review of self-reported cognitive failures in psychological disorders and substance use, identifying 21 papers in total.

Results: Papers identified studied trauma, mood, and anxiety disorders, and schizophrenia. Substance use papers included nicotine, alcohol, cannabis, and ecstasy use. Cognitive failures were increased in some but not all papers; the most consistent findings were for depression, PTSD, and daily smokers of nicotine. Subjective failures did not correlate closely with neuropsychological outcomes in any disorders. We were unable to discern distinct profiles of failures for each disorder; rather they may reflect emotional dysregulation more broadly.

Conclusions: The real world cognitive experiences of people with psychological disorders may differ to their performance in the clinic or lab. It is important that self-reports of minor cognitive issues are considered as both a potential risk and a maintaining factor of illness. Substance use also needs to be considered in assessing cognitive failures.