Genetic control of drug resistance: Assignment ofama-1 to Chinese hamster chromosome 7, confirmation of assignment of genes coding for TK,GALK, and ACP to chromosome 7, and tentative assignment of TPI to chromosome 8

The gene which specifies a subunit of RNA polymerase II, ama-1,is assigned to chromosome 7 in the Chinese hamster. The assignment of genes coding for TK, GALK, and ACP to chromosome 7 is confirmed, with a provisional regional assignment of TK and GALK to 7q. On the basis of one clone with six subclones, a provisional assignment of TPI to Chinese hamster chromosome 8 is made. With the assignment of tkand ama-1to chromosome 7 in the CHO cell line Amal, this chromosome is shown to have two selectable markers.     

Anger Cognitions and Cardiovascular Recovery Following Provocation

The current study describes the creation and validation of the Anger Cognitions Inventory (ACI) to assess the cognitive appraisals associated with resentful and reflective anger. The ACI was created based on a content analysis of self-reports of participants' thoughts and feelings following anger provocation in the laboratory. Exploratory and confirmatory factor analyses on two separate college student samples (N = 267 and N = 276, respectively) revealed five subscales which could validly be grouped into resentful and reflective anger. Convergent and divergent validity data showed that resentful anger correlated positively with anger-out/trait anger and reflective anger correlated positively with anger-in/brooding. A second study showed positive correlations between rumination and delayed cardiovascular recovery following anger provocation. Limitations of both studies include restricted samples which limit generalizability of results and cardiovascular recovery data collected in Study II which does not include assessment of autonomic balance between vagal and sympathetic responsivity.     

16S Ribosomal DNA Typing for Identification of Pathogens in Patients with Bacterial Keratitis

The identification of pathogens in patients with bacterial keratitis remains problematic because standard diagnostic tests are negative for 40 to 60% of patients. A cross-sectional study was undertaken to determine if PCR and sequence analysis of 16S ribosomal DNA (rDNA) could be used to detect bacterial pathogens in patients with keratitis. Corneal specimens were collected for culture and rDNA typing. Variable segments of each rDNA specimen were amplified by PCR, sequenced, and aligned with the sequences in GenBank. Eleven patients had microbiologically documented bacterial keratitis, while 17 patients had keratitis due to other causes. Nine (82%) of 11 bacterial keratitis patients were PCR positive; each sequencing result matched the culture results. Seventeen (100%) patients with nonbacterial keratitis were PCR negative. Our data suggest that 16S rDNA typing holds promise as a rapid alternative to culture for identifying pathogens in patients with bacterial keratitis.     

A novel method for rapid genotypic identification of alpha 1-antitrypsin variants.

There is worldwide growing awareness of alpha 1-antitrypsin deficiency (AATD), a major hereditary disorder in Caucasians. The gold standard for laboratory diagnosis of AATD is thin-layer isoelectrofocusing (IEF), which is labor intensive and should be performed in reference laboratories. The aim of this study was to find an easy, fast, and cheap method for detecting alpha1-antitrypsin S and Z variants, the most frequent variants associated with AATD. The novel method herein described is based on SexAI/Hpy99I RFLP. We studied samples from 90 subjects enrolled in the Italian National Registry for AATD, previously typed by isoelectrofocusing. We found a complete agreement among our results, IEF, and genotypes obtained by standard methods. We concluded that this novel method combines efficiency, ease, swiftness, and low cost.     

Spontaneous dissecting aneurysms of coronary arteries in a cardiac allograft

Dissecting aneurysms of coronary arteries are a rare finding and have never been reported in a cardiac allograft. We found two spontaneous dissecting aneurysms on the middle third of both the left anterior descending and the right coronary arteries in a female cardiac transplantation recipient. She died 43 days after cardiac transplantation after developing human cytomegalovirus pneumonia and pancreatitis. Dissecting coronary aneurysms, microfoci of subendocardial coagulative necrosis, and area of subepicardial dystrophic calcifications were discovered at necropsy examination.     

A role for the basal ganglia in nicotinic modulation of the blink reflex

Summary In humans and rats we found that nicotine transiently modifies the blink reflex. For blinks elicited by stimulation of the supraorbital branch of the trigeminal nerve, nicotine decreased the magnitude of the orbicularis oculi electromyogram (OOemg) and increased the latency of only the long-latency (R2) component. For blinks elicited by electrical stimulation of the cornea, nicotine decreased the magnitude and increased the latency of the single component of OOemg response. Since nicotine modified only one component of the supraorbitally elicited blink reflex, nicotine must act primarily on the central nervous system rather than at the muscle. The effects of nicotine could be caused by direct action on lower brainstem interneurons or indirectly by modulating descending systems impinging on blink interneurons. Since precollicular decerebration eliminated nicotine's effects on the blink reflex, nicotine must act through descending systems. Three lines of evidence suggest that nicotine affects the blink reflex through the basal ganglia by causing dopamine release in the striatum. First, stimulation of the substantia nigra mimicked the effects of nicotine on the blink reflex. Second, haloperidol, a dopamine (D₂) receptor antagonist, blocked the effect of nicotine on the blink reflex. Third, apomorphine, a D₂ receptor agonist, mimicked the effects of nicotine on the blink reflex.     

Differential effects of the antioxidant alpha-lipoic acid on the proliferation of mitogen-stimulated peripheral blood lymphocytes and leukaemic T cells

The effects of the antioxidant alpha-lipoic acid (LA) on the proliferation of mitogen-stimulated human peripheral blood lymphocytes (HPBL) were investigated in comparison to its effects on the proliferation of two leukaemic T cell lines, Jurkat and CCRF-CEM. At low mM concentrations, LA inhibited in a dose-dependent manner DNA synthesis of HPBL stimulated with either phorbol myristate acetate (PMA) in combination with ionomycin (IoM), or phytohaemagglutinin (PHA). At similar concentrations, LA inhibited the proliferation of Jurkat and CCRF-CEM cells. However, LA was preferentially cytotoxic to the leukaemic cell lines. The selective toxicity of LA to Jurkat cells was shown by electron microscopy (EM) to be due to the induction of apoptosis. Furthermore, LA had different effects on the secretion of interleukin-2 (IL-2) and steady-state levels of IL-2 mRNA in mitogen-stimulated HPBL depending on the mitogens used. LA dramatically increased the induction of IL-2 mRNA and IL-2 protein secretion in PMA/IoM-stimulated HPBL, whereas it inhibited these in HPBL stimulated with PHA. The differential effects of LA on normal and leukaemic T lymphocytes may indicate a new route towards development of therapeutic agents.     

Theophylline and fibrocystic breast disease

After literature reports linking fibrocystic breast disease (FBD) to methylxanthine ingestion, a pilot study was undertaken to investigate the possible contribution of theophylline to this effect. The major goal of this project was to measure the effect of theophylline therapy on FBD in asthmatic women. All women attending an allergy clinic or an obstetrics/gynecology clinic over a 9-month period were examined to clinically assess FBD and were asked to complete a detailed questionnaire covering health history, other risk factors, and drug and dietary methylxanthines. The sample included 62 asthmatic women, 66 allergic but not asthmatic women, and 72 nonallergic and nonasthmatic women. By use of the FBD clinical taxonomy with its 19-point scale going from 0 to 18 that was developed for this study, the three groups did not differ significantly in terms of mean severity of FBD. On analyzing the effect of each of the methylxanthines on FBD severity, there is clear evidence that total methylxanthines was a contributing factor in FBD severity with or without adjustment for relevant variables, such as age, menopause, pregnancies, and groups. Theophylline was significant only when adjustments were made for age, pregnancy, and menopause in contrast to caffeine that was only significant with no adjustments.