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At least 253 records · Page 14Linked to original sources
PubMed2001

A novel neurodevelopmental syndrome responsive to 5-hydroxytryptophan and carbidopa.

Tryptophan hydroxylase (TPH; EC 1.14.16.4) catalyzes the first rate-limiting step of serotonin biosynthesis by converting l-tryptophan to 5-hydroxytryptophan. Serotonin controls multiple vegetative functions and modulates sensory and alpha-motor neurons at the spinal level. We report on five boys with floppiness in infancy followed by motor delay, development of a hypotonic-ataxic syndrome, learning disability, and short attention span. Cerebrospinal fluid (CSF) analysis showed a 51 to 65% reduction of the serotonin end-metabolite 5-hydroxyindoleacetic acid (5HIAA) compared to age-matched median values. In one out of five patients a low CSF 5-methyltetrahydrofolate (MTHF) was present probably due to the common C677T heterozygous mutation of the methylenetetrahydrofolate reductase (MTHFR) gene. Baseline 24-h urinary excretion showed diminished 5HIAA values, not changing after a single oral load with l-tryptophan (50-70 mg/kg), but normalizing after 5-hydroxytryptophan administration (1 mg/kg). Treatment with 5-hydroxytryptophan (4-6 mg/kg) and carbidopa (0.5-1.0 mg/kg) resulted in clinical amelioration and normalization of 5HIAA levels in CSF and urine. In the patient with additional MTHFR heterozygosity, a heterozygous missense mutation within exon 6 (G529A) of the TPH gene caused an exchange of valine by isoleucine at codon 177 (V177I). This has been interpreted as a rare DNA variant because the pedigree analysis did not provide any genotype-phenotype correlation. In the other four patients the TPH gene analysis was normal. In conclusion, this new neurodevelopmental syndrome responsive to treatment with 5-hydroxytryptophan and carbidopa might result from an overall reduced capacity of serotonin production due to a TPH gene regulatory defect, unknown factors inactivating the TPH enzyme, or selective loss of serotonergic neurons.

5-Hydroxytryptophan↗
PubMed1978

Variant chromosome 3 (inv3) in normal newborns and their parents, and in children with mental retardation.

The chromosomes of 102 normal newborn babies (51 boys and 51 girls) born at term, their parents, and 45 nonrelated children with mental retardation at the level of imbecility were investigated by fluorescence microscopy using propyl quinacrine mustard. In each of the 11 families, one of the parents had a variant chromosome 3 that was interpreted as resulting from a pericentric inversion of the brilliant band (or C band) only (inv3). In four cases inv3 was transmitted to the child. The frequency of inv3 in newborn boys and girls was 2 and 6% respectively, and in adult men and women 5 and 6% respectively. In children with mental retardation of unknown etiology the inv3 was detected in five cases (11.1%). This difference from normal persons was not significant.

Child↗
PubMed1978

A microprobe analysis of Gomori-positive glial cells in the rat arcuate nucleus.

Astrocytes and microglial cells in the arcuate nucleus of the rat hypothalamus contain lipofuscin-like granules which react with chrome alum gallocyanin and exhibit endogenous peroxidase activity. These granules were assessed with energy dispersive X-ray microanalysis and compared to neuronal dense bodies and glial cytoplasm. The granules are distinguished by a consistent content of sulphur and a frequent presence of calcium. The localization of other elements such as iron, copper, potassium and chlorine is impaired by methodical difficulties. The sulphur content as well as the endogenous peroxidase activity is interpreted as indicating a special variant of lipofuscin. The presence of calcium is discussed with respect to recent concepts of glia as a regulator of the ionic environment of the CNS.

Animals↗
PubMed1997

Malignant mesothelioma of the pleura. The reproducibility of the immunohistological diagnosis.

The reproducibility of the histopathological diagnosis of pleural malignant mesothelioma (MM), after supplementing routine H&E stain by immunohistochemistry (IH) in 77 cases of original diagnoses of MM, was assessed by examining interobserver variation between five pathologists. A battery of commercial antibodies (cytokeratins, vimentin, HMFG-2, anti Leu-M1 [CD15], BerEP4, B72.3 [TAG-72], carcinoembyonic antigen), considered to be useful in enhancing diagnostic accuracy, was used. The number of definitively classified tumors (accepted MM plus rejected MM) increased from 57 on H&E stain to 60 after IH, with 59 (76.6%) cases being accepted as true MM. Based on IH, the chance-adjusted interobserver agreement was poor (kappa w = 0.29) and lower than that observed on previous H&E alone. The intraobserver agreement for four of the five pathologists was rather good (kappa w = 0.54-0.56). The inter- and intraobserver concordance was higher in accepting than excluding the cases as MM. A larger number of cases were classified by all reviewers as mixed or sarcomatous variants after IH. In the interpretation of each immunostain, kappa values ranged from 0.19 for B72.3 to 0.62 for HMFG-2, which were respectively the least and the most consistently interpreted immunostains. The information additionally contributed by IH did not seem to change the pathologists' diagnoses very much in comparison with those made by routine H&E stain. Until highly specific and sensitive probes for the positive identification of MM become available, a careful scrutiny of routinely stained preparations still remains the most rewarding component of the diagnostic pathway.

Clinical Laboratory Techniques↗
PubMed1998

Mesenteric and celiac duplex scanning: a validation study.

PURPOSE: To validate the accuracy of previously established duplex ultrasound criteria for > or =50% superior mesenteric artery (SMA) and celiac artery (CA) stenosis by comparison with arteriography. METHODS: Duplex criteria established retrospectively in our laboratory in 1991 identified an end-diastolic velocity (EDV) > or =45 cm/sec, or no flow signal, as highly sensitive (100%) and specific (92%) indicators for SMA stenosis > or =50% or occlusion. EDV was more accurate (95%) than peak systolic velocity (PSV), which had a maximal accuracy of 86% at a PSV > or =300 cm/sec, with low sensitivity (62%), but high specificity (100%). For CA, accurate velocity thresholds were not identified, but we subsequently noted that retrograde common hepatic artery flow direction from SMA collateral was highly predictive of severe CA stenosis or occlusion. Since publication of those findings, 243 mesenteric duplex scans were performed for clinical evaluation of suspected chronic mesenteric ischemia. Angiographic confirmation was available for a subset of 46. SMA and CA diameters were measured on lateral aortograms by observers blinded to the duplex results, and the original duplex diagnostic criteria were tested for accuracy. In addition, receiver operator characteristic curve analysis was performed on the velocity data to identify the most accurate velocity thresholds in the new data. RESULTS: Duplex was technically adequate in 98% of SMA, 96% of CA, and 89% of hepatic arteries, and arteriograms were adequate in 100% of SMA and 98% of CA. For the SMA, EDV > or =45 cm/sec again provided the best sensitivity (90%), specificity (91%), positive predictive value (90%), negative predictive value (91%), and overall accuracy (91%). As in the retrospective study, PSV > or =300 cm/sec provided low overall accuracy (81%), low sensitivity (60%), but high specificity (100%). Lowering the PSV threshold improved sensitivity but reduced accuracy. For CA, retrograde common hepatic artery flow direction was 100% predictive of severe CA stenosis or occlusion. Velocity data in CA provided accuracy not found in the original study. EDV > or =55 cm/sec or no flow signal had best overall accuracy (95%) with high sensitivity (93%) and specificity (100%). PSV > or =200 cm/sec or no signal also had excellent accuracy (93%), sensitivity (93%), and specificity (94%). In addition, three of four anatomic anomalies were correctly identified by duplex. These included one right hepatic and one common hepatic artery originating from the SMA, and one common celiacomesenteric trunk. CONCLUSION: This validation analysis confirms that duplex velocity criteria are accurate in the identification of mesenteric occlusive disease. Retrograde common hepatic artery flow direction correctly predicts severe CA stenosis or occlusion. Duplex ultrasound may also identify mesenteric anatomic variants that can influence study interpretation.

Aged↗
PubMed1999

Massive osteolysis of the mandible: report of a case with multifocal bone loss.

Osteolysis of the jaws has been reported in association with infection, cysts, neoplasia, and metabolic, endocrine, or hematologic abnormalities. Rare cases of idiopathic osteolysis have also been recorded. We report the case of a 10-year-old girl with mandibular basal and alveolar bone resorption that has continued over a period of 9 years. The patient has subsequently developed bilateral resorption of the ascending rami and condyles. The maxilla is uninvolved. Investigations included radiology, computerized tomography, scintigraphy, hematology, serum chemistry, endocrinology, histopathology, microbiology, and immunology. Neutrophil chemotaxis, chemiluminescence, and random migration values were low but within the normal range. These findings are interpreted as indicating an unusual variant of massive osteolysis.

Child↗
PubMed1967

Microbial growth on C1 compounds. Uptake of [14C]formaldehyde and [14C]formate by methane-grown Pseudomonas methanica and determination of the hexose labelling pattern after brief incubation with [14C]methanol.

1. A study has been made of the incorporation of carbon from [(14)C]formaldehyde and [(14)C]formate by cultures of Pseudomonas methanica growing on methane. 2. The distribution of radioactivity within the non-volatile constituents of the ethanol-soluble fractions of the cells, after incubation with labelled compounds for periods of up to 1min., has been analysed by chromatography and radioautography. 3. Radioactivity was fixed from [(14)C]formaldehyde mainly into the phosphates of the sugars, glucose, fructose, sedoheptulose and allulose. 4. Very little radioactivity was fixed from [(14)C]formate; after 1min. the only products identified were serine and malate. 5. The distribution of radioactivity within the carbon skeleton of glucose, obtained from short-term incubations with [(14)C]methanol of Pseudomonas methanica growing on methane, has been investigated. At the earliest time of sampling over 70% of the radioactivity was located in C-1; as the time increased the radioactivity spread throughout the molecule. 6. The results have been interpreted in terms of a variant of the pentose phosphate cycle, involving the condensation of formaldehyde with C-1 of ribose 5-phosphate to give allulose phosphate.

Carbon Isotopes↗
PubMed1994

Molecular phylogeny of part of the env gene of HIV-1 strains isolated in Côte d'Ivoire.

OBJECTIVES: To examine the genetic variation of HIV-1 isolates in Abidjan, Côte d'Ivoire, and to determine the extent to which phylogenetic trees based on sequence information of part of the env gene containing the principal neutralizing domain are representative for documenting genetic variability. DESIGN: Phylogenetic comparison of 13 HIV-1 strains isolated from patients in Abidjan with previously documented HIV-1 strains of different geographic origin. METHODS: To sequence a 900 base-pair fragment of the env gene containing V3, V4, V5 and the beginning of gp41 of three to four clones per isolate. Phylogenetic tree analysis was performed with the software package TREECON. RESULTS: Eleven HIV-1 isolates of Abidjan were classified as genotype A, while two were classed as genotypes B and D. Intra-genotype A distances at the nucleotide level were a maximum of 14.1%. Inter-genotype distances between genotype A and genotypes B, C, and D varied from 16.0 to 22.6%. Phylogenetic trees, based on sequence data of a 300 base-pair fragment containing the V3 loop, showed significant differences in tree topology and statistical confidence with phylogenetic trees based on sequence data of the 900 base-pair env fragment. CONCLUSIONS: Genotype A Côte d'Ivoire HIV-1 strains, which comprise 11 out of 13 isolates, predominate in Abidjan, which may indicate a local burst of particular variants. Phylogenetic trees should be interpreted with caution when based on a more limited number of nucleotides, such as the V3 region.

Base Sequence↗
PubMed1987

Lymphocyte predominance Hodgkin's disease: a reappraisal based upon histological and immunophenotypical findings in relapsing cases.

The clinical, morphological and immunological findings in nine cases of relapsing lymphocyte predominance Hodgkin's disease (LPHD) are examined. Six patients had initial biopsies demonstrating nodular lymphocytic and/or histiocytic (L&H) LPHD; Leu-M1 was not expressed by any of the atypical cells in these cases. All six demonstrated one or more recurrences of nodular L & H LPHD; four are currently free of disease, one died of non-Hodgkin's lymphoma and another died of leukaemia. Two patients had initial biopsies demonstrating diffuse LPHD, with only rare multilobated atypical cells (L & H variants). Both patients had recurrences interpreted as mixed cellularity Hodgkin's disease, 10 and 15 years after initial therapy and both died with lymphocyte depleted Hodgkin's disease. The atypical cells in the initial biopsies and in subsequent recurrences failed to express Leu-M1, but did express leukocyte common antigen. The initial biopsy from the final patient was histologically interpreted as focal involvement by LPHD, but interfollicular Hodgkin's disease was considered after the Leu-M1 stain revealed additional atypical cells. The disease relapsed and the patient died with typical nodular sclerosing Hodgkin's disease. The pattern of the relapses supports the concept that the histological entity of LPHD may include several distinct clinicopathological subgroups.

Biopsy↗
PubMed1996

MTS1 gene mutations in archival oral squamous cell carcinomas.

Multiple tumor suppressor gene 1 (MTS1) has been found mutated or deleted in a variety of human cancers. Our purpose was to identify and characterize MTS1 gene mutations in primary oral squamous cell carcinomas (SCCs) in each of the three exons of the MTS1 gene. Seventeen archival samples of oral SCC were evaluated for the presence of MTS1 mutations using single strand conformation polymorphism (SSCP) and DNA sequencing. Three of 17 tumors exhibited MTS1 gene mutations: one tumor exhibited a mutation in exon 2 and two tumors exhibited mutations at the splice site junction of intron 2 and exon 3. Three tumors also exhibited a common base change in the 3' untranslated region of exon 3, which is interpreted as a likely polymorphic variant. An examination of the three tumors exhibiting MTS1 point mutations revealed no unique characteristics relative to p53 immunohistochemical activity, mitotic frequency, or degree of histologic differentiation. This study indicates that MTS1 gene mutations may be involved in at least a minor proportion of oral SCCs.

Adolescent↗
PubMed1977

Electroencephalographic variants and genetic predisposition to schizophrenia.

Schizophrenic patients (249) were divided into those with and those without a family history of major functional psychosis. The same patients were then divided into those with entirely normal electroencephalograms and those whose traces contained some variant of normal. Traces were interpreted without knowledge of the patients' identities, and the question of the presence or absence of positive heredity had been decided without knowledge of the patients' electroencephalographic status, so that the discovery that normal electroencephalograms correlated highly significantly with positive heredity, and vice versa, commands attention. It is considered in the setting of previous work on psychoses and organic and electroencephalographic findings.

Brain↗
PubMedDate not supplied

"Lumps" and "bumps" that mimic acute aortic and brachiocephalic vessel injury.

Laceration of the thoracic aorta or brachiocephalic vessels due to blunt trauma is relatively common. In such cases, prompt and accurate diagnosis followed by timely surgery is essential. These injuries typically occur at the aortic isthmus and can usually be readily identified at aortography, which remains the standard of reference for diagnosis. However, numerous anatomic variants that manifest as "lumps" or "bumps" on aortograms can mimic true vascular injury, thereby leading to false-positive or false-negative diagnosis. These variants include aortic spindle, classic or atypical ductal diverticula, and infundibula of the brachiocephalic arteries and adjacent branches or of the right third intercostal artery. Ductus diverticula typically occur at the isthmus and have smooth, uninterrupted margins with gently sloping shoulders. Infundibula are also smoothly marginated but can occur in a variety of locations and generally taper into one or more vessels at their apex. Knowledge of the imaging appearances of these anatomic variants is necessary for correct interpretation of aortograms of the aorta and brachiocephalic vessels in blunt trauma patients.

Adult↗
PubMed1981

Echocardiographic appearance of the Chiari network: differentiation from right-heart pathology.

As echocardiography is being used more often, its value and accuracy are becoming more fully appreciated. Coincident with wider application of this imaging technique is the potential for identifying normal anatomic variants and their possible erroneous interpretation as pathologic states. In this report we describe the M-mode and two-dimensional echocardiographic features of a congenital remnant known as the Chiari network. This structure can present as a highly mobile, highly reflectant echo target that can be seen in several locations in the right atrium. We report here an index case that could be well examined echocardiographically and that was a cause of considerable concern due to the presence of congestive heart failure and a history of staphylococcal endocarditis. The presence of the Chiari network was confirmed pathologically. Subsequently, we found similar echocardiographic findings in 19 of 1248 patients (1.5%) studied in our laboratory. This congenital remnant, which is found pathologically in 2-3% of normal hearts, could be confused with valve disruption, vegetation or other mass lesion, particularly when associated with a suggestive clinical situation.

Adult↗
PubMed1981

Functional interdependence of pseudopodia in Amoeba proteus stimulated by light-shade difference.

Polytactic cells of Amoeba proteus were exposed to localized photic stimulation. When a pseudopodium is stimulated to advance, by shading it, other pseudopodia are retracted. Activation of the shaded front is the primary response, and contraction of other fronts the secondary one. When a pseudopodium is inhibited by illuminating its frontal segment, or when it is allowed to enter the bright zone in the course of migration, it slows down and stops but its eventual retraction depends on the existence of other possible directions for the endoplasmic flow. Therefore, if other active pseudopodia are lacking, the front suppressed by light cannot retreat effectively until new fronts arise in other body regions kept in shade. In all experimental situations the development of new fronts or the activation of forward flow in lateral pseudopodia precedes the contraction of the former leading pseudopodium. Also the reversal of direction of the endoplasmic streaming begins at the new front, and then it gradually extends until it reaches the former front. The results confirm the interdependence of different pseudopodia in the same individual and they contradict the concept that pseudopodia behave as separate functional units. On the other hand, they indicate that formation of new pseudopodia should not be explained as a simple secondary effect of contraction of the older ones but, on the contrary, as a phenomenon that initiates the changes in the pattern of flow in amoeba. The general interpretation is based on this variant of the pressure-flow theory of amoeboid movement, which attributes the motive power to the contractile activity of the whole cell cortex and the steering role to events taking place in the front of the migrating cell.

Amoeba↗
PubMed1994

MR diagnosis of meniscal tears: analysis of causes of errors.

OBJECTIVE: MR imaging of the knee is an accurate method for diagnosing meniscal tears. However, MR findings do not always agree with surgical findings. In a retrospective study, we analyzed the various causes of incorrect MR diagnoses. MATERIALS AND METHODS: We reviewed a series of 400 MR examinations for suspected meniscal tears in which the diagnostic accuracy was 90%. In this group, we found 70 patients in whom the original MR diagnosis did not agree with the surgical findings. Three musculoskeletal radiologists independently reviewed each of the 70 MR examinations without knowledge of the original interpretation or the surgical findings. Their interpretations and the MR images then were correlated with the surgical findings. The original incorrect diagnoses were categorized as being due to unavoidable errors, errors in interpretation, or errors made because of equivocal MR findings of a tear. Unavoidable errors were defined as false-positive and false-negative diagnoses that could not be avoided, even in retrospect. RESULTS: Of the 83 original diagnostic errors made in the MR evaluation of 800 menisci, 33 (40%) were unavoidable errors, 32 (39%) were due to equivocal MR findings, and 18 (21%) were due to interpretation errors. The unavoidable errors consisted of 21 missed meniscal tears and 12 false-positive MR diagnoses. In the false-positive cases, the menisci were interpreted as torn on MR images by all three observers, but no tear was found at arthroscopy. Subtle MR findings that were equivocal for a tear caused both false-positive and false-negative diagnoses. Seven of the 18 interpretation errors occurred when normal variants were mistaken for a tear. CONCLUSION: Using conventional coronal and sagittal spin-echo MR imaging, we could not identify 21 (6%) of the 333 meniscal tears, even in retrospect. In addition, subtle findings that are equivocal for a tear may still make MR diagnosis of every torn meniscus difficult even for experienced radiologists. Unavoidable false-positive diagnoses due to healed tears or tears missed at arthroscopy are an infrequent problem occurring in only 1.5% of the original 800 menisci evaluated with MR imaging.

Diagnostic Errors↗
PubMed1989

[Duodenocolonic fistula caused by carcinoma of the cecum].

Duodenocolonic fistulas of malignant origin are an uncommon finding. The point of origin of the fistula is almost always cancer of the hepatic angle of the colon. We report a patient with this rare entity which originated from a cecal carcinoma, and interpret it as an anatomic variant of the subhepatic position. The cases published are reviewed and the difficulties of reaching a therapeutic decision once the diagnosis is established are highlighted.

Carcinoma↗
PubMed1982

[Incontinentia pigmenti achromians (systematized depigmented nevus)].

Two girls of 1 1/2 und 4 years age and described with linear, arch-like depigementations which appeared in early childhood. In both children no additional abnormalities could be found. The problem of terminology is briefly discussed, and it is proposed to interpret this syndrome as a variant of a systematized naevus depigmentosus. There seems to be no justification for turning this clinical entity into a new syndrome, when the only clinical signs are the characteristic depigmentations without any additional abnormalities.

Child, Preschool↗