Cytotoxicity and NMR spectral assignments of ergolide and bigelovin

A 10-year-old left-handed girl with a developmental stutter and agenesis of the corpus callosum with associated hydrocephalus ceased stuttering immediately upon initiation of steroid therapy for colitis. Steroid taper resulted in a recurrence of the stutter and resumption for treatment of recrudescent colitis caused its disappearance again. Baseline agenesis of the corpus callosum with hydrocephalus and the patient's course in the face of the known effects of steroids on white matter lend support to the hypothesis that stuttering reflects anomalous dominance and/or atypical interhemispheric connectivity, as evidenced by the fact that presumed alterations of white matter tracts affected speech rhythms/stuttering.     

Ebstein's anomaly (morphologic and morphometric study

12 hearts with Ebstein's anomaly were studied. This disease is a combined anomaly of heart formation with dysplasia of the folds of the tricuspid valve (TV), its tendinous chordas and papillary muscles, dysplasia of the trabecular part of the right ventricle and dysplastic interrelationships between TV and the right ventricle: attachment by short chordas of posterior and septal folds of TV with the right ventricle walls, anomalous distal attachment of the anterior fold of TV. "Atrialisation" of the right ventricle is the reflection of the folds dysplasia the extreme form of which is the loss of communication between TV and trabecular part and formation of the direct communication between TV and the infundibular part of the right ventricle.     

Incidence of Helicobacter pylori infection in Ghanaian patients with dyspeptic symptoms referred for upper gastrointestinal endoscopy

There is a lack of information in the United Kingdom on the prevalence of third molars in older patients. The aim of this study was therefore to define the pattern of lower third molar retention in UK dental practice attenders aged 35 years and over. A random sample of 599 eligible patients from a rural dental practice were included in the study. Information was obtained from clinical notes and panoramic radiographs. Data collected included age, gender, presence or absence of lower third molars, number of teeth present in the lower arch and eruption status. Two hundred and sixty-four (44.1 per cent) had at least one lower third molar present (mean age = 57.1 years) while 335 (55.9 per cent) had no lower third molars (mean age = 50.2 years). The data suggest that a greater proportion of men than women retain at least one lower third molar although this finding was not statistically significant. Seventy per cent of retained lower third molars reported in the study were fully erupted. Sixty per cent were vertically placed. There was an association between age and number of teeth present (chi 2 = 38.85, 4DF, P < 0.05), older patients having fewer lower teeth. These data suggest that a large number of patients can expect to keep their lower third molars beyond the age of 35 years and that in many cases a conservative "wait and see' policy for lower third molars in the early twenties is appropriate.     

Uptake and metabolism of serotonin by rat adrenal tissue in vitro

After incubation of separate zones of rat adrenals with radioactively labelled serotonin--at concentrations at which the amine had been previously shown to stimulate aldosterone biosynthesis--the tissue radioactivity was several times higher in the capsular ("zona glomerulosa") than in the decapsulated portions of the glands. High doses of unlabelled serotonin diminished the accumulation of radioactivity, but only when added simultaneously with the tracer. In the course of the incubation, radioactive 5-hydroxy-3-indoleacetic acid, i.e. the deaminated metabolite of serotonin, rapidly appeared in the medium. Most of the radioactive material accumulated by the adrenal was recovered in the cytosol fraction and was no longer identical with serotonin, but consisted mainly of 5-hydroxy-3-indoleacetic acid and another, unidentified metabolite. Unaltered serotonin was found in capsular adrenal tissue extracts only when a monoamine oxidase inhibitor (nialamide) has been added to the incubation medium. Rapid uptake and metabolism thus appeared to be the predominant features of the interaction of incubated adrenal tissue with serotonin. These events may have obscured the possible binding of very small amounts of serotonin to receptor sites. The observed accumulation of radioactivity in adrenal tissue was mainly due to delayed outflow of intracellulary formed metabolite, since 5-hydroxy-3indoleacetic acid was neither taken up by incubated adreanls nor bound by adrenal cytosol. No evidence of serotonin storage in the zona glomerulosa was found in these studies.     

Organellar and cytosolic localization of four phosphoribosyl diphosphate synthase isozymes in spinach

Four cDNAs encoding phosphoribosyl diphosphate (PRPP) synthase were isolated from a spinach (Spinacia oleracea) cDNA library by complementation of an Escherichia coli Deltaprs mutation. The four gene products produced PRPP in vitro from ATP and ribose-5-phosphate. Two of the enzymes (isozymes 1 and 2) required inorganic phosphate for activity, whereas the others were phosphate independent. PRPP synthase isozymes 2 and 3 contained 76 and 87 amino acid extensions, respectively, at their N-terminal ends in comparison with other PRPP synthases. Isozyme 2 was synthesized in vitro and shown to be imported and processed by pea (Pisum sativum) chloroplasts. Amino acid sequence analysis indicated that isozyme 3 may be transported to mitochondria and that isozyme 4 may be located in the cytosol. The deduced amino acid sequences of isozymes 1 and 2 and isozymes 3 and 4 were 88% and 75% identical, respectively. In contrast, the amino acid identities of PRPP synthase isozyme 1 or 2 with 3 or 4 was modest (22%-25%), but the sequence motifs for binding of PRPP and divalent cation-nucleotide were identified in all four sequences. The results indicate that PRPP synthase isozymes 3 and 4 belong to a new class of PRPP synthases that may be specific to plants.     

Cross-contamination with Mycobacterium tuberculosis: an epidemiological and laboratory investigation

OBJECTIVE: To investigate possible cross-contamination of laboratory specimens, as suggested by an increased incidence of newly diagnosed patients with tuberculosis, many of whom had all negative smears for acid-fast bacilli and only one positive Mycobacterium tuberculosis culture referred to as "negative smears, one positive" or NSOP. METHODS: Medical-record reviews were performed for all patients with NSOP results diagnosed at this facility within a 9-month period. Laboratory logbooks were reviewed for all isolates processed; DNA fingerprinting was performed on available isolates. RESULTS: Of 80 patients with NSOP results, 45 (56%) were found to have false-positive cultures resulting from laboratory contamination with H37Ra, an avirulent stock strain of Mycobacterium tuberculosis. CONCLUSION: Laboratory cross-contamination resulted in the false diagnosis of tuberculosis in at least 45 individuals. Use of the Mycobacteria Growth Indicator Tube may have contributed to these contamination incidents by detecting small numbers of contaminating mycobacteria that may not have been detected with less sensitive media.     

Flow cytometry in the diagnosis and classification of malignant lymphoma and leukemia

DNA content and light scatter were measured by flow cytometry (FCM) in 103 patients including 43 patients with non-Hodgkin's lymphoma (NHL), eight patients with Hodgkin's disease (HD), 17 patients with acute lymphoblastic leukemia (ALL), ten patients with acute nonlymphocytic leukemia (ANLL), and 25 patients with chronic lymphoid leukemias. Controls consisted of 42 nonneoplastic specimens obtained from lymph nodes, spleen, bone marrow, and peripheral blood. Each specimen was analyzed after staining with a hypotonic solution of propidium iodide using nuclei isolated from chicken erythrocytes as an internal standard. The DNA content and light scatter of the human populations was expressed as a ratio between the DNA content (or light scatter) of the human G0--G1 cells and that of the chicken erythrocytes nuclei. The mean DNA ratio for the 42 nonneoplastic samples was 2.58 +/- 0.045 (SD). In these samples the DNA coefficient of variation of the human G0--G1 peak ranged from 1.48--3.28% (mean, 2.33 +/- 0.54%). The FCM data in the NHL was compared to morphologic diagnoses made according to the "working formulation of NHL for clinical usage" recently proposed by a panel of international experts. Eight of 17 (47%) low grade NHL, one of two (50%) mycosis fungoides, ten of 14 (71%) intermediate grade NHL, nine of ten (90%) high grade NHL, nine of 17 (53%) ALL, three of ten (30%) ANLL, and seven of 25 (28%) chronic lymphoid leukemias had abnormal DNA ratios indicative of aneuploidy. In addition, several cases had normal DNA ratios but G0--G1 coefficients of variation outside of the normal range. All cases of HD had normal DNA values except one case with a small percentage of near tetraploid cells. The mean percentage of cells with S-phase DNA content for the low grade NHL (2.2 +/- 0.8%) was significantly lower than that of the intermediate grade NHL (12.1 +/- 4.9%; P less than 0.0001). The mean S-phase value for the intermediate grade NHL was significantly lower than that of the high grade NHL (22.6 +/- 11.1%; P less than 0.001). The three prognostic categories of NHL designated by the new formulation were clearly distinguishable by the FCM data. Light scatter was not particularly useful for distinguishing nonneoplastic from neoplastic populations. The mean light scatter coefficient of variation of the ALL (15.2%) was significantly lower than that of ANLL (20.5%), however (P less than 0.04).