Ventricular arrhythmias during coronary angiography in patients with angina pectoris or chest pain syndromes

Of 7,915 patients undergoing coronary angiography from 1978 to 1983, 39 (25 men and 14 women with a mean age of 57 years [range 37 to 79]) had sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) during the procedure. Nine patients had atypical chest pain and 30 had typical angina. Fifteen had had a previous myocardial infarction. One patient had a history of VT or VF. Electrocardiograms taken at rest revealed a prolonged QT interval in 14. A normal ejection fraction was found in 79%. Coronary angiography revealed that 10 patients had 3-vessel disease, 15 had 1- or 2-vessel disease and 14 had normal coronary arteries. The VT or VF was seen with injection of contrast medium into the right coronary artery in 24, the left coronary artery in 10 and vein bypass grafts in 5 patients. Of the episodes of VT or VF, 67% occurred after injection of contrast medium into a minimally diseased coronary artery. In patients in whom VT or VF occurred after injection into a minimally diseased coronary artery, the arrhythmia was preceded by bradycardia, usually with pronounced widening of the QRS and QT intervals. This response was significantly different from that in patients in whom VT or VF occurred after injection into a coronary artery with significant stenosis; in these patients, VT or VF was initiated by a single premature ventricular contraction on a T wave. VT or VF was successfully cardioverted in all instances, without further arrhythmias.     

Quantitation and characterization of a species-specific and embryo stage-dependent 55-kilodalton phosphoprotein also present in cells transformed by simian virus 40.

A 55-kilodalton (kDal) protein was detected recently in primary cultures of day 12 mouse embryos by immunoprecipitation with serum from simian virus 40 (SV40) tumor-bearing hamsters (T serum), Preliminary evidence suggested that this protein was similar to a cellular 55-kDal protein induced after SV40 transformation of mouse cells. We now show that specific approximately 55-kDal [35S]methionine-labeled proteins precipitate from primary cultures of midgestation mouse, rat, and hamster embryos on addition of T serum or monoclonal antiserum prepared against the SV40-induced mouse 55-kDal proteins. The two-dimensional maps of the [35S]methionine-labeled tryptic peptides of the mouse, hamster, and rat embryo proteins are similar to the maps of the corresponding proteins from SV40-transformed cells. Primary cells from midgestation mouse, hamster, or rat embryos contain one-third to one-half as much 55-kDal protein as a SV40-transformed mouse fibroblast cell and nearly the same amount as F9 mouse embryonal carcinoma cells. The amount of 55-kDal protein is greatly reduced on replating the mouse, rat, or hamster embryo primary cells. The amount of this protein in mouse embryos is dependent on the stage of the embryo. The embryo proteins are phosphoproteins.     

Mechanisms of Compartmental Purkinje Cell Death and Survival in the Lurcher Mutant Mouse

The Lurcher mutant mouse is characterized by its ataxic gait and loss of cerebellar Purkinje cells and their afferents, granule cells and olivary neurons, during the first weeks of postnatal development. For the 50 years since its discovery, the heterozygous Lurcher mutant has served as an important model system for studying neuron–target interactions in the developing cerebellum and cerebellar function. The identification of the Lurcher (Lc) gene over 10 years ago as a gain-of-function mutation in the δ2 glutamate receptor (GluRδ2) led to extensive studies of cell death mechanisms in the Lc/+ cerebellum. The advantage of this model system is that GluRδ2⁺ receptors and GluRδ2 ^Lc channels are expressed predominantly in Purkinje cells, making it possible to study the effects of a well-characterized leak current in a well-defined cell type during a critical phase of neuronal development. Yet there is still controversy surrounding the mechanisms of neuronal death in Lc/+ Purkinje cells with competing hypotheses for necrotic, apoptotic, and autophagic cell death pathways as a consequence of the excitotoxic stress caused by the GluRδ2 ^Lc leak current. The goal of this review is to summarize recent studies that critically test the role of various cell death pathways in Lc/+ Purkinje cell degeneration with respect to evidence for the molecular heterogeneity of Purkinje cells. We propose that the expression of putative survival factors, such as heat shock proteins, in a subset of cerebellar Purkinje cells may affect cell death pathways and account for the pattern and diverse mechanisms of Lc/+ Purkinje degeneration.     

Risk factors for Clostridium difficile carriage and C. difficile-associated diarrhea in a cohort of hospitalized patients

A prospective cohort study of 399 consecutive patients in a single ward over an 11-month period was conducted to identify risk factors for nosocomial C. difficile colonization and diarrhea. The incidence of asymptomatic carriage was 13.0/100 patient admissions and the incidence of C. difficile-associated diarrhea was 7.8/100 patient admissions. Increased age and more severe underlying illness were associated with increased risk of C. difficile carriage and diarrhea. Multivariate models adjusting for age and severity of underlying disease associated two risk factors with asymptomatic C. difficile carriage: stool softeners (relative risk [RR] = 2.04) and antacids (RR = 1.80). Five risk factors were associated with C. difficile-associated diarrhea: cephalosporin use (RR = 2.07), penicillin use (RR = 3.41), enemas (RR = 3.26), gastrointestinal stimulants (RR = 3.06), and stool softeners (RR = 1.74). C. difficile was a common nosocomial infection on this ward, resulting in asymptomatic carriage more often than diarrhea and accounting for one-fifth of all cases of nosocomial diarrhea.     

MR evaluation of synovial injury in shoulder trauma

The purpose of this study was to determine magnetic resonance imaging (MRI) findings relevant to synovial injury of the shoulder in patients with and without acute shoulder trauma. Three hundred and nine consecutive shoulder MRI studies (185—male, 124—female, 50 ± 15 years old) were retrospectively evaluated for findings suggestive of synovial injury including rupture and/or diverticulum of the joint capsule, bursa, and biceps tendon sheath (BTS), ganglion/synovial cyst, geyser phenomenon, and sequel of previous shoulder dislocation (Hill–Sachs deformity). Patients with one or more of these findings were included in the MR-positive group, whereas the remaining subjects were used as MR negatives. Based on their medical records, patients were also divided into trauma and non-trauma groups, and statistical analysis was performed to evaluate the association between the aforementioned MRI findings and history of shoulder trauma. Fifty-six patients were included in the MR-positive group and 253 in the MR-negative group. In MR-positive group, the incidence of capsular rupture (CR) and subacromial/subdeltoid (SASD) bursal rupture was higher in trauma patients, whereas the incidence of BTS diverticulum and ganglion cyst was higher in subjects without trauma. Significant association was found between the history of acute trauma and CR, SASD bursal rupture, BTS rupture, and Hill–Sachs deformity. In shoulder MR examination, presence of CR and/or SASD bursal rupture is strongly suggestive of acute shoulder trauma. In addition, BTS rupture and Hill–Sachs deformity are more prevalent in patients with acute shoulder trauma. The presence of these features should alert MRI readers to assess for additional trauma-related internal derangements, if a respective history has not been provided.     

Multiple endocrine adenomatosis type I in pregnancy

A 26-year-old woman, gravida 1, para 0, having episodes of confusion, slurred speech, and blurred vision in pregnancy was documented to have severe hypoglycemia with elevated serum insulin and C-peptide levels. Emergency treatment for hypoglycemia was necessary several times during pregnancy. A healthy female infant was delivered after oxytocin induction of labor. Post partum the patient had numerous episodes of severe hypoglycemia in spite of constant intravenous glucose. Computerized tomographic scan of the pancreas failed to show a lesion, whereas pancreatic arteriography revealed a 2 cm mass in the tail of the pancreas. Partial pancreatectomy was performed 6 days after delivery. Microscopic examination of the tissue confirmed the presence of an insulinoma. Hypercalcemia developed together with elevated parathyroid hormone levels. The presence of an insulinoma, hypercalcemia, and a history of hyperparathyroidism in two relatives indicates that this is a case of multiple endocrine adenomatosis type I first diagnosed during pregnancy.     

Effects of vocal task and respiratory phase on prephonatory chest wall movements.

A vocal reaction time paradigm was used to explore prephonatory respiratory kinematics. Movements of the rib cage and abdomen were recorded prior to production of utterances differing in length and intensity, and vocal responses were elicited in different phases and volumes of the quiet breathing cycle. A velocity threshold was used to distinguish prephonatory adjustments from the cyclical movements of the chest wall that are characteristic of quiet breathing. The results suggest that a variety of prephonatory kinematic events can occur prior to initiation of vocalization in response to a stimulus. Further, prephonatory movements appear to be adaptive in that they are influenced by the length of the utterance to be spoken and the respiratory volume at the time of voice initiation.     

Intellectual development in school-aged children with asymptomatic congenital cytomegalovirus infection

Congenital cytomegalovirus infection occurs in about 1% of live births. Although symptomatic congenital infection often results in severe developmental deficits and mental retardation, about 90% have asymptomatic infection. Previous studies of the intellectual development in children with asymptomatic congenital cytomegalovirus have resulted in mixed findings. To control for the effects of hearing impairment (which occurs in about 15% of asymptomatic children) on intelligence scores, we tested 18 prospectively followed, normally hearing, school-aged children with asymptomatic congenital cytomegalovirus (15 black, ten male) and 18 controls matched for age, sex, race, school grade, and socioeconomic status. Children were tested via the Wechsler Intelligence Scale for Children-Revised, the Kaufman Assessment Battery for Children, and the Wide Range Achievement Test. Multivariate analysis revealed no differences between groups on intelligence scores or subscales, achievement scores, or incidence of learning disabilities (defined as significant discrepancy between intelligence and achievement), and mean scores for both groups were very close to national norms. It is concluded that the 25,000 children born in the United States each year with asymptomatic congenital cytomegalovirus and normal hearing are not likely to be at increased risk of mental impairment.     

The investigation of factors underlying deficits in self-awareness and self-regulation

Primary objective : To examine a theoretical model which suggests that a contribution of both psychological and neuropsychological factors underlie deficits in self-awareness and self-regulation.

Research design : Multivariate design including correlations and analysis of variance (ANOVA).

Methods : Sixty-one subjects with acquired brain injury (ABI) were administered standardized measures of self-awareness and self-regulation. Psychological factors included measures of coping-related denial, personality-related denial and personality change. Neuropsychological factors included an estimate of IQ and two measures of executive functioning that assess capacity for volition and purposive behaviour.

Main outcomes and results : The findings indicated that the relative contribution of neuropsychological factors to an outcome of deficits in self-awareness and self-regulation had a more direct effect than psychological factors. In general, measures of executive functioning had a direct relationship, while measures of coping-related and personality-related denial had an indirect relationship with measures of self-awareness and self-regulation.

Conclusion : The findings highlighted the importance of measuring both neuropsychological and psychological factors and demonstrated that the relative contribution of these variables varies according to different levels of self-awareness and self-regulation.