A dissociation between the ability to print and write cursively in lower-case letters

This paper reports the case of a patient with a peripheral spelling impairment who is much more severely impaired at writing in lower-case letters than in upper-case letters. This pattern can be observed when writing both words and single letters of the alphabet. Despite this, his problems in writing lower-case letters are no longer present when he is writing cursively. This case therefore indicates that the ability to print letters in lower-case can be selectively impaired in the absence of similar problems in printing upper-case letters or in writing lower-case letters cursively. In terms of the model of writing put forward by Ellis (1982, 1988), this suggests that allographic level representations for print handwriting styles can be functionally dissociated from allographic representations for cursive styles.     

Photoacoustic analysis of proteins: volumetric signals and fluorescence quantum yields

A series of proteins has been examined using time-resolved, pulsed-laser volumetric photoacoustic spectroscopy. Photoacoustic waveforms were collected to measure heat release for calculation of fluorescence quantum yields, and to explore the possibility of photoinduced nonthermal volume changes occurring in these protein samples. The proteins studied were the green fluorescent protein (GFP); intestinal fatty acid binding protein (IFABP), and adipocyte lipid-binding protein (ALBP), each labeled noncovalently with 1-anilinonaphthalene-8-sulfonate (1,8-ANS) and covalently with 6-acryloyl-2-(dimethylamino)naphthalene (acrylodan); and acrylodan-labeled IFABP and ALBP with added oleic acid. Of this group of proteins, only the ALBP labeled with 1,8-ANS showed significant nonthermal volume changes at the beta = 0 temperature (approximately 3.8 degrees C) for the buffer used (10 mM Tris-HCI, pH 7.5) (beta is the thermal cubic volumetric expansion coefficient). For all of the proteins except for acrylodan-labeled IFABP, the fluorescence quantum yields calculated assuming simple energy conservation were anomalously high, i.e., the apparent heat signals were lower than those predicted from independent fluorescence measurements. The consistent anomalies suggest that the low photoacoustic signals may be characteristic of fluorophores buried in proteins, and that photoacoustic signals derive in part from the microenvironment of the absorbing chromophore.     

A virulent nonencapsulated Haemophilus influenzae

Nontypeable Haemophilus influenzae strain INT1 was isolated from the blood of a young child with clinical signs of meningitis following acute otitis media. No immunologic or anatomic predisposition of this child for invasive bacterial infection with an unusual organism was documented. Sensitive ELISA proved the absence of intra- or extracellular capsular polysaccharide production by INT1 and Southern blot analysis confirmed the lack of an intact capsulation (cap) gene locus within the chromosome. Nevertheless, INT1 established bacteremia and meningitis in infant and weanling rat models of invasive H. influenzae infection. High-molecular-weight DNA isolated from INT1 was shown to confer an invasive phenotype on transformation of a nonencapsulated, avirulent laboratory strain of H. influenzae. Together these findings imply the presence of one or more as-yet-undiscovered, noncapsular virulence factors of H. influenzae that are capable of mediating invasive disease and resistance to immunologic clearance.     

Brachytherapy and breast cancer

The study compares, in true adenocarcinoma of the cardia and in adenocarcinoma in Barrett's esophagus, the prevalence of early cancers and their outcome in those patients suitable for resection surgery. From 1980 to 1993, 26 of 350 (7.4%) resected adenocarcinomas of the esophago-gastric junction were pathologically staged as early cancer or pT1. The prevalence of early cancer was 3.7% (11/294) for true cancer of the cardia and 27% (15/56) for cancer in Barrett's esophagus (P < 0.001). Ten of the 15 latter cancers were diagnosed during endoscopic surveillance for benign Barrett's esophagus. Among early cancers, there were four mucosal and 22 submucosal tumours; of the latter, eight had lymph node metastasis and seven neoplastic permeation of lympho-hematic vessels. The most frequently used surgical procedure was esophago-gastric resection and gastric pull-up. Postoperative morbidity was 15.4%, and hospital mortality 3.8%. Excluding postoperative deaths, the overall 5-year survival rate was 79% for early cancer of the cardia and 83% for early cancer in Barrett's esophagus (log rank test = 0.0214, P = 0.88). Overall, the survival rate was 100% in the absence of lymph node metastasis and 43% in the presence of node metastasis (log rank test = 15.811, P = 0.0001). Only one of five patients with both node metastasis and vessel infiltration survived longer than 5 years. In conclusion, the prevalence of early cancer was significantly greater for cancer in Barrett's esophagus than for true cancer of the cardia. Prognosis of the two types of tumour after resection surgery was the same and depended on lymph node status and neoplastic permeation of lympho-hematic vessels.     

The development of novel and selective p56lck tyrosine kinase inhibitors

Early T-cell receptor mediated signal transduction involves the activation of several tyrosine protein kinases. One of these tyrosine kinases, p56lck, is expressed primarily in T-cells and Natural Killer (NK) cells and has been shown to be critical for their proliferative and effector functions. Indandiones have been identified as a potent and selective chemical class that inhibits p56lck.     

Silent myocardial ischaemia and left ventricle hypertrophy in diabetic patients

The purpose of this study was to evaluate the ability of three noninvasive techniques to detect silent myocardial ischaemia and analyse the factors associated with this condition, particularly left ventricular hypertrophy, in diabetic patients. An ECG stress test, a thallium-201 myocardial scintigraphy with dipyridamole intravenous infusion, ambulatory 48 h ECG monitoring and an echocardiographic study were performed in 92 diabetic patients without cardiac symptoms but with > or = 2 additional cardiovascular risk factors. At least one of these tests was positive in 28 patients (30.4%), suggesting silent myocardial ischaemia. Twenty-four of these patients had a coronary angiography which showed significant coronary stenosis in only 9 cases. An accurate echocardiographic tracing was obtained in 79 patients, particularly in 7 of the 9 with coronary stenosis. Left ventricular hypertrophy was detected in 34 patients, 6 of whom had coronary stenosis. In patients with left ventricular hypertrophy, the positive predictive values of myocardial scintigraphy and the ECG stress test were respectively 50% and 100%, as compared to only 33% and 11% in those without hypertrophy. In summary, coronary stenoses were found in < 10% of asymptomatic diabetic patients with > or = 2 cardiovascular risk factors, but more frequently in individuals with left ventricular hypertrophy. Thus, silent myocardial ischaemia should be searched for first in diabetic patients with hypertrophy, for which the stress test was the most accurate detection method in this study.