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V Toma

Publications and source records attributed to V Toma.

At least 19 recordsLinked to original sources
PubMed2001

Application of a lectin from the mushroom Polysporus squamosus for the histochemical detection of the NeuAcalpha2,6Galbeta1,4Glc/GlcNAc sequence of N-linked oligosaccharides: a comparison with the Sambucus nigra lectin.

The lectin from the mushroom Polysporus squamosus (PSL) has an extended carbohydrate combining site, which exhibits a high specificity and affinity toward the NeuAc5alpha2,6Galbeta1,4Glc/GlcNAc trisaccharide sequence of asparagine-linked oligosaccharides. Therefore, PSL should be a superior reagent to the lectin from Sambucus nigra (SNA), which does not discriminate between alpha2,6-linked NeuAc5 present either in asparagine- or serine/threonine-linked oligosaccharides. We have prepared a digoxigenin-conjugated PSL and applied it for histochemistry and blotting. We observed a more restricted staining pattern by PSL as compared to SNA in paraffin sections from different rat organs. Pretreatment of sections with N-glycanase F abolished PSL staining indicating that it interacts only with asparagine-linked oligosaccharides. Furthermore, PSL staining was neuraminidase sensitive. In contrast, SNA staining was only partially sensitive to N-glycanase F pretreatment demonstrating that it was in part due to alpha2,6-linked NeuAc5 present in serine/threonine-linked oligosaccharides. The most striking observation in this regard was that PSL, in contrast to SNA, did not stain the mucus of sheep submandibular gland, which is extremely rich in serine/threonine-linked Neu5Acalpha2,6N-acetylgalactosamine. Furthermore, in some tissues neuraminidase pretreatment resulted in increased intensity of SNA staining probably due to binding to exposed terminal N-acetylgalactosamine residues. Collectively, these results indicate that PSL is a useful tool for the histochemical detection of alpha2,6-linked NeuAc5 in asparagine-linked oligosaccharides.

Agaricales↗
PubMed2001

A prospective open-label treatment trial of olanzapine monotherapy in children and adolescents with bipolar disorder.

OBJECTIVE: The goal of this study was to assess the effectiveness and tolerability of olanzapine in the treatment of acute mania in children and adolescents. METHODS: This was an 8-week, open-label, prospective study of olanzapine monotherapy (dose range 2.5-20 mg/day) involving 23 bipolar youths (manic, mixed, or hypomanic; 5-14 years old). Weekly assessments were made using the Young Mania Rating Scale (YMRS), Clinical Global Impressions Severity Scale (CGI-S), Brief Psychiatric Rating Scale, and Children's Depression Rating Scale. Adverse events were assessed through self-reports, vital sign and weight monitoring, laboratory analytes, and extrapyramidal symptom rating scales (Barnes Akathisia Scale, Simpson-Angus Scale, and Abnormal Involuntary Movement Scale). RESULTS: Twenty-two of the 23 youths (96%) completed the study. Olanzapine treatment was associated with significant improvement in mean YMRS score (-19.0 +/- 9.2, p < 0.001). Using predefined criteria for improvement of > or = 30% decline in the YMRS and a CGI-S Mania score of < or = 3 at endpoint, the overall response rate was 61%. Overall, olanzapine was well tolerated, and extrapyramidal symptom measures were not significantly different from baseline. Body weight increased significantly over the study (5.0 +/- 2.3 kg, p < 0.001). CONCLUSIONS: Open-label olanzapine treatment was efficacious and well tolerated in the treatment of acute mania in youths with bipolar disorder. Future placebo-controlled, double-blind studies are warranted.

Abdominal Pain↗
PubMed2000

Efficacy of olanzapine in acute bipolar mania: a double-blind, placebo-controlled study. The Olanzipine HGGW Study Group.

BACKGROUND: We compared the efficacy and safety of olanzapine vs placebo for the treatment of acute bipolar mania. METHODS: Four-week, randomized, double-blind, parallel study. A total of 115 patients with a DSM-IV diagnosis of bipolar disorder, manic or mixed, were randomized to olanzapine, 5 to 20 mg/d (n = 55), or placebo (n = 60). The primary efficacy measure was the Young-Mania Rating Scale (Y-MRS) total score. Response and euthymia were defined, a priori, as at least a 50% improvement from baseline to end point and as a score of no less than 12 at end point in the Y-MRS total score, respectively. Safety was assessed using adverse events, Extrapyramidal Symptom (EPS) rating scales, laboratory values, electrocardiograms, vital signs, and weight change. RESULTS: Olanzapine-treated patients demonstrated a statistically significant greater mean (+/- SD) improvement in Y-MRS total score than placebo-treated patients (-14.8 +/- 12.5 and -8.1 +/- 12.7, respectively; P<.001), which was evident at the first postbaseline observation 1 week after randomization and was maintained throughout the study (last observation carried forward). Olanzapine-treated patients demonstrated a higher rate of response (65% vs 43%, respectively; P =.02) and euthymia (61% vs 36%, respectively; P =. 01) than placebo-treated patients. There were no statistically significant differences in EPSs between groups. However, olanzapine-treated patients had a statistically significant greater mean (+/- SD) weight gain than placebo-treated patients (2.1 +/- 2.8 vs 0.45 +/- 2.3 kg, respectively) and also experienced more treatment-emergent somnolence (21 patients [38.2%] vs 5 [8.3% ], respectively). CONCLUSION: Olanzapine demonstrated greater efficacy than placebo in the treatment of acute bipolar mania and was generally well tolerated.

Acute Disease↗
PubMed2000

Thomsen-Friedenreich glycotope is expressed in developing and normal kidney but not in renal neoplasms.

The Thomsen-Friedenreich glycotope (TF) is considered a general carcinoma autoantigen and is therefore of importance in cancer diagnosis and immunotherapy. We report the distribution of the TF glycotope in developing and adult human kidney and renal neoplasms. A monoclonal antibody and the lectin amaranthin were used to study the TF and its sialylated, masked form by immunohistochemistry and immunoblotting. In developing kidney, the TF was restricted to the loop of Henle, distal tubules, and peripheral collecting ducts, whereas its sialylated form was detectable in all epithelial differentiations derived from the 2 embryonic anlagen, the metanephrogenic blastema being unreactive. This pattern was essentially preserved in adult kidney, with TF labeling beginning in the thick ascending limb and extending into the collecting ducts of outer medulla. The sialylated TF glycotope was additionally observed in ascending thin limbs. The TF was exclusively expressed in the luminal cell surface and hence was inaccessible to immune reactions. Analysis of a spectrum of renal neoplasms failed to detect the TF, with the exception of occasional staining of tubules in nephroblastoma. Moreover, the sialylated TF was only detectable in oncocytoma, chromophobe renal cell carcinoma, cystic nephroma, nephroblastoma, and nephroblastomatosis complex and occasionally in type 1 papillary renal cell carcinoma. Thus, the TF and its sialylated form are expressed in normal developing and adult kidney. However, the TF does not seem to represent a tumor-associated glycotope in human kidney, nor does it appear to be of value in diagnosis and immunotherapy of renal neoplasms.

Adult↗
PubMed2000

Nonunion of the mandible: an analysis of contributing factors.

PURPOSE: The aim of this study was to review our experience of nonunion of mandible fractures and to compare this information with the past and present literature. The analysis also evaluated risk factors and those conditions that lead to nonunion so that the complication may be better managed and possible avoided. PATIENTS AND METHODS: A retrospective review of mandible fractures in a major medical center was carried out on patients treated from 1994 through 1998. The nonunion cases were evaluated for factors such as age, sex, race, cause of fracture, location of fracture, delay until the patient obtained treatment, teeth in the fracture line, use of antibiotics, multiplicity of fractures, degree of fragmentation, medical problems, and drug and alcohol abuse. The adequacy of reduction and appropriateness of the fixation techniques were evaluated by analysis of the postoperative imaging studies. Postoperative occlusion and patient compliance were also included in the evaluation. RESULTS: Of the 906 patients with 1,432 mandible fractures, there were 25 nonunion complications, for an incidence of 2.8%. Most patients with nonunion were men who had received the fracture as a result of an altercation. The nonunion was frequently noted in the body, and was almost twice as common (39% vs 17.6%) in patients with multiple fractures than in a randomly selected group who did not have the complication. Delayed treatment was noted in 8 of the patients, and teeth were present in the fracture line in another 8. Alcohol and drug abuse were prevalent, and 1 of 5 of the patients removed their fixation devices. Eight patients were believed to be stabilized inadequately, and 1 patient also had a poor reduction. Osteomyelitis was a common complication. CONCLUSIONS: The incidence of nonunion appears to be unchanged over time regardless of the varied and presumably advanced methods of fixation and reduction. Multiple fractures were a contributory factor, and the body of the mandible appeared to be a common site. Many patients had osteomyelitis associated with the nonunion. Inadequate stabilization or reduction were important causes. Other suspected contributory factors included failure to provide antibiotics, delay in treatment, teeth in the fracture line, alcohol and drug abuse, inexperience of the surgeon, and lack of patient compliance.

Adult↗
PubMed1999

Differentiation-related expression of the Thomsen-Friedenreich glycotope in developing human lung and in lung carcinoma: lack of association with malignancy.

BACKGROUND: It has been proposed that the Thomsen-Friedenreich glycotope represents a general carcinoma-associated antigen and a candidate for the development of a tumor vaccine. However, the expression of the unmasked and masked (sialylated) forms in lung carcinomas, as well as in developing and adult human lung, has not been documented sufficiently. METHODS: Sections from 82 lung carcinomas, including squamous cell carcinomas, adenocarcinomas, and large cell and small cell carcinomas, as well as sections of developing and adult human lung were studied using the lectin amaranthin and a monoclonal antibody. RESULTS: All lung carcinomas but one bronchiolo-alveolar carcinoma were unreactive for the Thomsen-Friedenreich glycotope, whereas its sialylated form was detectable in well-differentiated squamous cell carcinomas and adenocarcinomas, including bronchiolo-alveolar carcinomas. Both unmasked and masked Thomsen-Friedenreich glycotopes were undetectable in large cell and small cell lung carcinomas. In all developmental stages of lung, the Thomsen-Friedenreich glycotope was expressed only in epithelia of the most peripheral parts of the bronchial tree, whereas its sialylated form was expressed in epithelia of all parts of the bronchial tree. In adult lung, the Thomsen-Friedenreich glycotope was expressed in pneumocytes, whereas its sialylated form was expressed ubiquitously in all epithelia. CONCLUSIONS: The Thomsen-Friedenreich glycotope in human lung represents a differentiation antigen, rather than a carcinoma-associated antigen. The sialylated form is expressed constitutively in both developing and adult lung and well-differentiated lung carcinomas. Thus, the Thomsen-Friedenreich glycotope is of limited value in the diagnosis of lung carcinoma, and there is no rationale for a Thomsen-Friedenreich glycotope-based immunotherapy for patients with this disease.

Adenocarcinoma↗
PubMed1999

Focal loss of CD44 variant protein expression is related to recurrence in superficial bladder carcinoma.

The majority of papillary transitional cell carcinomas of the bladder are localized tumors at initial diagnosis; identification of those developing recurrence and an aggressive behavior is important. CD44 variant proteins have been implicated in tumor progression and metastasis, and a correlation with adverse prognosis has been demonstrated in a variety of human tumors. Here, the usefulness of conventional CD44 protein immunohistochemistry as a prognostic parameter for recurrence of superficial transitional cell carcinomas was assessed in paraffin sections of 241 tumors with long-term follow-up. A highly significant association was found between focal loss of CD44v3 and -v6 immunostaining and short recurrence-free interval in noninvasive (pTa) transitional cell carcinomas (P = 0.005), but not in minimally invasive (pT1) carcinomas (P = 0.78). Our results indicate the value of conventional CD44 immunohistochemistry as an additional tool for identifying patients at high risk for recurrence of pTa transitional cell carcinomas. They also point to biological differences between noninvasive and minimally invasive transitional cell carcinomas of the bladder.

Carcinoma, Transitional Cell↗
PubMed1999

Specialized expression of simple O-glycans along the rat kidney nephron.

Glycosyltransferases can exhibit tissue-specific expression. By histochemistry glycosyltransferases and their products can be localized to specific cell types in organs of complex cellular composition. We have applied the lectin Amaranthin, having a nominal specificity for Galbeta1,3GalNAcR and Neu5Ac2,3Galbeta1, 3GalNAcalpha-R, and a monoclonal antibody raised against Galbeta1, 3GalNAcalphaR to examine the distribution of these simple O-glycans in adult rat kidney. The monoclonal antibody stained ascending thin limbs of Henle, distal convoluted tubules, and collecting ducts of cortex and outer medulla. Remarkably, the ascending thick limb of Henle, located between ascending thin limb and distal convoluted tubules, was unreactive. However, Amaranthin staining was detectable in ascending thick limbs of Henle, in addition to the structures positive with the monoclonal antibody. In kidney extracts, two bands of approximately 160 kDa and >210 kDa were reactive with both Amaranthin and the monoclonal antibody. One band at approximately 200 kDa, and a smear at approximately 100 kDa, were reactive only with Amaranthin. Our data show that in rat kidney simple O-linked glycans are expressed in a highly specialized manner along the renal tubule and can be detected only on a few glycoproteins. This may reflect a cell-type-specific expression of the corresponding glycosyltransferases.

Animals↗
PubMed1999

Olanzapine versus placebo in the treatment of acute mania. Olanzapine HGEH Study Group.

OBJECTIVE: The primary intent of this study was to compare the efficacy and safety of olanzapine and placebo in the treatment of acute mania. METHOD: The design involved a random-assignment, double-blind, placebo-controlled parallel group study of 3 weeks' duration. After a 2- to 4-day screening period, qualified patients were assigned to either olanzapine (N = 70) or placebo (N = 69). Patients began double-blind therapy with either olanzapine, 10 mg, or placebo given once per day. After the first day of treatment, the daily dose could be adjusted upward or downward, as clinically indicated, by one capsule (olanzapine, 5 mg/day) within the allowed range of one to four capsules. The primary efficacy measure in the protocol was defined as a change from baseline to endpoint in total score on the Young Mania Rating Scale. Clinical response was defined a priori as a decrease of 50% or more from baseline in Young Mania Rating Scale total score. RESULTS: The olanzapine group experienced significantly greater mean improvement in Young Mania Rating Scale total score than the placebo group. On the basis of the clinical response criteria, significantly more olanzapine-treated patients (48.6%) responded than those assigned to placebo (24.2%). Somnolence, dizziness, dry mouth, and weight gain occurred significantly more often with olanzapine. There were no statistically significant differences between the olanzapine-treated and placebo-treated patients with respect to measures of parkinsonism, akathisia, and dyskinesias. No discontinuations of treatment due to adverse events occurred in the olanzapine treatment group. CONCLUSIONS: The results from this study suggest that compared with placebo, olanzapine has superior efficacy for the symptoms of acute mania.

Acute Disease↗
PubMed1994

Postcolumn radionuclide detection of low-energy beta emitters in capillary electrophoresis.

A postcolumn radionuclide detection system for capillary electrophoresis (CE) is described. Eluant from an electrophoresis capillary is directed onto a peptide binding membrane that has been previously coated with a solid scintillator. The membrane is moved in a preselected pattern relative to the fixed capillary outlet during electrophoresis. Light emission from scintillation is imaged onto a charge-coupled device (CCD) using a series of 35-mm camera lenses. Detection of two low-energy beta- emitters (35S and 3H) not previously reported for capillary electrophoresis is demonstrated. The separation efficiencies are similar to those obtained with on-line UV detection. The response for 35S-labeled methionine is linear (r2 = 0.996) from 66 amol to 11 fmol. Detection limits are 88 zmol (0.03 Bq) for 32P-labeled analytes, 17 amol (0.94 Bq) for 35S-labeled analytes, and 8 fmol (8.5 Bq) for 3H-labeled analytes.

Beta Particles↗
PubMed1978

In vitro activity of oxolinic acid and nalidixic acid against common urinary pathogens: a comparative study.

A study was carried out to compare the sensitivity of 500 bacterial strains, isolated from patients with urinary tract infections, to oxolinic acid and nalidixic acid. The results showed that whilst both antibacterial agents were similar in their bacterial spectrum they were not identical in terms of cross-sensitivity or resistance. Where there was a difference in sensitivity, this was always in flavour of oxolinic acid and was particularly evident in the case of Staphylococcus, Pseudomonas, Serratia, Klebsiella, Proteus (especially P. rettgeri), and to a lesser extent Citrobacter.

Bacteria↗