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1.
Chemosphere ; 45(6-7): 1033-43, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11695580

ABSTRACT

Atmospheric mercury was monitored from January 1997 through the end of December 1999 in eight sampling locations in Connecticut. Four sampling locations were chosen along the shores of Long Island Sound and four were chosen in interior sections of Connecticut. Sampling locations were chosen to represent both rural and urban sectors. Average concentrations of gaseous and particulate mercury were found to be 2.06 ng/m3 and 10.5 pg/m3, respectively. The weekly average wet deposition fluxes of mercury and methylmercury over the three-year sampling period were measured to be 611 and 11 microg/ha/week, respectively. Concentrations of gaseous, particulate and wet flux of mercury were found to be significantly higher in urban areas than the rural sampling locations. There was, however, no significant difference between the mean gaseous and particulate concentrations of mercury in coastal and inland sampling locations. No significant difference was observed either between the wet fluxes of total mercury in coastal and inland sampling locations and there was no spatial gradient for mercury concentration and deposition. The data of this study suggest that vehicular traffic and localized emission sources in urban areas play a significant role in determining the atmospheric concentration of mercury in Connecticut.


Subject(s)
Air Pollutants/analysis , Mercury/analysis , Vehicle Emissions/analysis , Cities , Connecticut , Environmental Monitoring , Gases , Geography , Particle Size
2.
J Hazard Mater ; 87(1-3): 155-69, 2001 Oct 12.
Article in English | MEDLINE | ID: mdl-11566407

ABSTRACT

The kinetics of oxidation of perchloroethylene (PCE), trichloroethylene (TCE), three isomers of dichloroethylene (DCE) and vinyl chloride (VC) by potassium permanganate (KMnO(4)) were studied in phosphate-buffered solutions of pH 7 and ionic strength approximately 0.05 M and under isothermal, completely mixed and zero headspace conditions. Experimental results have shown that the reaction appears to be second order overall and first order individually with respect to both KMnO(4) and all chlorinated ethenes (CEs), except VC. The degradation of VC by KMnO(4) is a two-consecutive-step process. The second step, being the rate-limiting step, is of first order in VC and has an activation energy (E(a)) of 7.9+/-1 kcal mol(-1). The second order rate constants at 20 degrees C are 0.035+/-0.004 M(-1) s(-1) (PCE), 0.80+/-0.12 M(-1) s(-1) (TCE), 1.52+/-0.05 M(-1) s(-1) (cis-DCE), 2.1+/-0.2 M(-1) s(-1) (1,1-DCE) and 48.6+/-0.9 M(-1) s(-1) (trans-DCE). The E(a) and entropy (DeltaS(*)) of the reaction between KMnO(4) and CEs (except VC) are in the range of 5.8-9.3 kcal mol(-1) and -33 to -36 kcal mol(-1) K(-1), respectively. Moreover, KMnO(4) is able to completely dechlorinate CEs, and the increase in acidity of the solution due to CE oxidation by KMnO(4) is directly proportional to the number of chlorine atoms in CEs.


Subject(s)
Hydrocarbons, Chlorinated/chemistry , Potassium Permanganate/chemistry , Kinetics , Oxidation-Reduction , Temperature
3.
J Hazard Mater ; 87(1-3): 171-86, 2001 Oct 12.
Article in English | MEDLINE | ID: mdl-11566408

ABSTRACT

Fenton's reagent is the result of reaction between hydrogen peroxide (H(2)O(2)) and ferrous iron (Fe(2+)), producing the hydroxyl radical (-*OH). The hydroxyl radical is a strong oxidant capable of oxidizing various organic compounds. The mechanism of oxidizing trichloroethylene (TCE) in groundwater and soil slurries with Fenton's reagent and the feasibility of injecting Fenton's reagent into a sandy aquifer were examined with bench-scale soil column and batch experiment studies. Under batch experimental conditions and low pH values ( approximately 3), Fenton's reagent was able to oxidize 93-100% (by weight) of dissolved TCE in groundwater and 98-102% (by weight) of TCE in soil slurries. Hydrogen peroxide decomposed rapidly in the test soil medium in both batch and column experiments. Due to competition between H(2)O(2) and TCE for hydroxyl radicals in the aqueous solutions and soil slurries, the presence of TCE significantly decreased the degradation rate of H(2)O(2) and was preferentially degraded by hydroxyl radicals. In the batch experiments, Fenton's reagent was able to completely dechlorinate the aqueous-phase TCE with and without the presence of soil and no VOC intermediates or by-products were found in the oxidation process. In the soil column experiments, it was found that application of high concentrations of H(2)O(2) with addition of no Fe(2+) generated large quantities of gas in a short period of time, sparging about 70% of the dissolved TCE into the gaseous phase with little or no detectable oxidation taking place. Fenton's reagent completely oxidized the dissolved phase TCE in the soil column experiment when TCE and Fenton's regent were simultaneously fed into the column. The results of this study showed that the feasibility of injecting Fenton's reagent or H(2)O(2) as a Fenton-type oxidant into the subsurface is highly dependent on the soil oxidant demand (SOD), presence of sufficient quantities of ferrous iron in the application area, and the proximity of the injection area to the zone of high aqueous concentration of the target contaminant. Also, it was found that in situ application of H(2)O(2) could have a gas-sparging effect on the dissolved VOC in groundwater, requiring careful attention to the remedial system design.


Subject(s)
Hydrogen Peroxide/chemistry , Iron/chemistry , Soil Pollutants/analysis , Solvents/chemistry , Trichloroethylene/chemistry , Water Pollutants, Chemical/analysis , Oxidation-Reduction
6.
Clin Chem ; 38(3): 426-31, 1992 Mar.
Article in English | MEDLINE | ID: mdl-1547565

ABSTRACT

Examination of 4379 routine urinalysis specimens with dipsticks sensitive to ascorbic acid showed that 22.8% were positive specimens. The mean urinary vitamin C concentration in this population was 2120 mumol/L. There was a high rate of false-negative dipstick results for hemoglobin in patients with vitamin C in the urine. The highest false-negative rates were observed in urine samples containing less than 50 erythrocytes per high-power field. In further experiments when volunteers consumed supplemental oral USP vitamin C at doses of 100, 250, 500, and 1000 mg or vitamin C-containing fruit juices, even the lowest doses of oral vitamin C or juice resulted in sufficient urinary vitamin C to produce false-negative dipstick results in hemoglobin and glucose testing. To prevent potentially dangerous false-negative results, screening urinalysis protocols relying only on dipstick testing should include a check for urinary vitamin C or use a dipstick that is not subject to vitamin C interference.


Subject(s)
Ascorbic Acid/urine , Reagent Strips , Urinalysis/standards , Ascorbic Acid/administration & dosage , False Negative Reactions , Glycosuria/urine , Hemoglobinuria/urine , Humans
7.
CMAJ ; 146(2): 108-9, 1992 Jan 15.
Article in English | MEDLINE | ID: mdl-1735030
8.
Am J Clin Pathol ; 93(5): 689-93, 1990 May.
Article in English | MEDLINE | ID: mdl-2327368

ABSTRACT

Twenty patients with malignant disease and Bence Jones (BJ) proteins were studied to determine the optimum urine collections for the detection and monitoring of light chain proteinuria. A 24-hour urine protein collection was followed by individual collections of each sequentially voided specimen over the same time interval. Samples were analyzed quantitatively for protein, and protein electrophoresis was performed on each specimen. Only one patient had BJ protein nondetectable by protein electrophoresis in the early morning specimen. Six patients had one or more random specimens (excluding the early morning specimens) absent for BJ protein on protein electrophoresis. Three patients had nondetectable protein on electrophoresis of the 24-hour specimen despite having some random specimens positive. All random specimens with protein values exceeding 0.20 g/L had BJ protein visibly detectable on electrophoresis. Thirteen specimens with protein less than 0.05 g/L still had BJ protein detected by electrophoresis. There was a linear relationship between the early morning protein concentration and the total 24-hour urinary protein production. The authors conclude that early morning specimens or 24-hour urine collections are preferable for the detection and monitoring of light chain proteinuria. These collection methods are not mutually exclusive because there are individual patients who will be negative in one collection but positive in the other.


Subject(s)
Bence Jones Protein/urine , Proteinuria/urine , Aged , Aged, 80 and over , Electrophoresis , Humans , Middle Aged , Monitoring, Physiologic , Multiple Myeloma/urine , Specimen Handling/methods
10.
Eur J Haematol ; 41(2): 176-81, 1988 Aug.
Article in English | MEDLINE | ID: mdl-3410011

ABSTRACT

Erythrocyte membrane (EM) abnormalities in a 16-yr-old boy with hypoalphalipoproteinemia resembling fish eye disease (FED-LS) were investigated. The proband's erythrocytes had markedly decreased osmotic fragility with target cells observed in the peripheral film. Analysis of his EM lipids revealed normal cholesterol and phospholipid content but a marked increase in phosphatidylcholine with concomitant decreases in phosphatidylethanolamine and sphingomyelin. Of the EM enzymes examined, acetylcholinesterase and superoxide dismutase activities were decreased while those of Na+-K+ ATPase, catalase and glutathione reductase were normal. 51Cr erythrocyte survival in the patient was slightly decreased. The observed changes in a number of structural and functional properties of erythrocytes in this disorder are indistinguishable from those previously described in homozygotes for familial lecithin:cholesterol acyltransferase (LCAT) deficiency. Thus, it is possible that in both of these disorders an abnormality of plasma LCAT activity causes, either directly or indirectly, functional and structural changes in the erythrocyte membrane.


Subject(s)
Corneal Opacity/blood , Erythrocytes, Abnormal/pathology , Hypolipoproteinemias/blood , Lipoproteins, HDL/blood , Adolescent , Erythrocyte Aging , Erythrocyte Membrane/enzymology , Erythrocyte Membrane/pathology , Female , Haptoglobins/analysis , Humans , Male
12.
J Surg Oncol ; 35(1): 35-8, 1987 May.
Article in English | MEDLINE | ID: mdl-3573771

ABSTRACT

A 63-year-old caucasian male with systemic leukocytoclastic vasculitis involving the skin, lungs, and gastrointestinal tract was found to have a renal cell carcinoma at autopsy. A 77-year-old-woman with a history of hypertension was felt to have temporal arteritis that was confirmed by biopsy. The autopsy revealed a renal cell carcinoma in association with widespread giant cell arteritis. The possible association of renal cell carcinoma with vasculitis and an assessment of the possible clinical usefulness are presented and cases of vasculitis with renal neoplasms are briefly reviewed.


Subject(s)
Carcinoma, Renal Cell/complications , Giant Cell Arteritis/etiology , Kidney Neoplasms/complications , Paraneoplastic Syndromes/etiology , Vasculitis/etiology , Aged , Female , Humans , Male , Middle Aged
13.
Clin Neuropathol ; 6(2): 49-54, 1987.
Article in English | MEDLINE | ID: mdl-3594975

ABSTRACT

The clinicopathological features of a patient with the transitional variant of the Shy-Drager syndrome is described. The only previously reported case of the transitional variant was reexamined and pathological similarities to the present case are reviewed. Both patients exhibited features of Parkinson's disease with Lewy bodies in the substantia nigra and locus ceruleus. Striato-nigral degeneration and olivo-ponto-cerebellar atrophy were evident in both cases. They can thus be considered as transitional forms of the Shy-Drager syndrome with feature of both Parkinson's disease and multiple system atrophy.


Subject(s)
Autonomic Nervous System Diseases/pathology , Brain/pathology , Parkinson Disease/pathology , Shy-Drager Syndrome/pathology , Aged , Humans , Locus Coeruleus/pathology , Male , Substantia Nigra/pathology
14.
Acta Med Scand ; 221(3): 291-8, 1987.
Article in English | MEDLINE | ID: mdl-3591467

ABSTRACT

A 16-year-old boy presented with bilateral arcus cornealis and markedly decreased plasma high density lipoprotein cholesterol. The plasma lipoprotein abnormalities, as well as decreased mass and activity of lecithin:cholesterol acyltransferase (LCAT), were similar to those described in patients with fish eye disease. Increased number of target cells and decreased osmotic fragility of the proband's erythrocytes were noted. The proband's father and one of his brothers showed intermediate plasma lipoprotein and LCAT alterations. The father's erythrocytes also showed abnormal osmotic fragility. The mother of the propositus had normal plasma lipoproteins and erythrocyte osmotic fragility, but her LCAT activity was also low. Many of these features suggest a disorder similar to fish eye disease which is clinically and biochemically distinct from other hypoalphalipoproteinemias.


Subject(s)
Corneal Opacity/diagnosis , Hypolipoproteinemias/blood , Lipoproteins, HDL/blood , Adolescent , Adult , Diagnosis, Differential , Female , Humans , Hypolipoproteinemias/diagnosis , Hypolipoproteinemias/genetics , Lipoproteins, LDL/blood , Male , Phosphatidylcholine-Sterol O-Acyltransferase/blood , Syndrome
16.
Can J Neurol Sci ; 13(2): 138-45, 1986 May.
Article in English | MEDLINE | ID: mdl-3013388

ABSTRACT

Two cases of malignant intracranial fibrous histiocytoma are presented. In Case 1 the tumour arose from the meninges and showed a disseminated spread throughout the neuroaxis. In the second case the tumour appeared to arise from within the brain substance. In this case surgical intervention and radiotherapy appeared to have achieved a cure, since no residual tumour was found at autopsy. The tumours were examined using ultrastructural and immunohistochemical techniques, which appeared advantageous in delineating this rare tumour from other intracranial neoplasms.


Subject(s)
Brain Neoplasms/pathology , Histiocytoma, Benign Fibrous/pathology , Meningeal Neoplasms/pathology , Aged , Biopsy , Brain Neoplasms/metabolism , Glial Fibrillary Acidic Protein/metabolism , Histiocytoma, Benign Fibrous/metabolism , Humans , Male , Meningeal Neoplasms/metabolism , Microscopy, Electron , Middle Aged , Nerve Tissue Proteins/metabolism , Vimentin/metabolism
17.
Acta Neuropathol ; 70(1): 10-6, 1986.
Article in English | MEDLINE | ID: mdl-3727930

ABSTRACT

The very existence of astroblastoma has been a question of considerable controversy, although there appears now to be sufficient documentation to establish it as a tenable entity. Due to the rarity of this tumor, little information exists in the literature as to its natural history, efficacy of therapy and its pathological and radiological appearance. We report three cases of astroblastoma, describing their natural history, the response to therapeutic interventions and their light microscopic, ultrastructural and immunohistochemical characteristics.


Subject(s)
Astrocytoma/pathology , Brain Neoplasms/pathology , Adult , Aged , Astrocytoma/complications , Astrocytoma/diagnostic imaging , Astrocytoma/therapy , Brain Neoplasms/complications , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/therapy , Combined Modality Therapy , Electroencephalography , Female , Histocytochemistry , Humans , Immunochemistry , Lomustine/therapeutic use , Male , Middle Aged , Phenobarbital/therapeutic use , Seizures/drug therapy , Seizures/etiology , Tomography, X-Ray Computed
18.
J Surg Oncol ; 25(1): 34-7, 1984 Jan.
Article in English | MEDLINE | ID: mdl-6420620

ABSTRACT

Ossifying skeletal muscle angiomas are relatively rare occurrences. The preoperative diagnosis is exceedingly difficult, although ossification may be reflected radiologically as a "Swiss cheese" appearance. Two patients are described whose skeletal muscle angiomas contained osseous tissue. The osseus tissue varied from microscopic foci to an abundant amount which was readily recognizable radiologically. The pathologic and radiological features are discussed and these appearances to hemangioma and lymphangioma are presented.


Subject(s)
Forearm , Hemangioma/pathology , Muscular Diseases/pathology , Ossification, Heterotopic/pathology , Adult , Female , Hemangioma/diagnostic imaging , Humans , Muscular Diseases/diagnostic imaging , Ossification, Heterotopic/diagnostic imaging , Radiography
19.
J Surg Oncol ; 24(3): 205-8, 1983 Nov.
Article in English | MEDLINE | ID: mdl-6632907

ABSTRACT

Cystadenoma of the appendix as a factor in the formation of mucous cysts (mucocele) of the appendix is well recognized. The diagnosis can be made in patients prior to surgery if appropriate investigations are utilized. A 66-year-old white woman with a complaint of increased frequency of bowel movements was investigated and a primary diagnosis of mucocele of the appendix was made preoperatively. As cecal involvement was suggested by these studies, a limited cecal resection was planned. These findings were confirmed at surgery. The appendectomy and limited cecal resection was curative for mucinous cystadenoma of the appendix.


Subject(s)
Appendiceal Neoplasms , Cystadenoma , Aged , Appendiceal Neoplasms/diagnosis , Appendiceal Neoplasms/surgery , Cystadenoma/diagnosis , Cystadenoma/surgery , Female , Humans
20.
Clin Chem ; 29(10): 1850-1, 1983 Oct.
Article in English | MEDLINE | ID: mdl-6137294

ABSTRACT

Hepatic infarction was observed post mortem in a 27-year-old man who died of aortic dissection. Blood had been sampled at admission and 12 and 19 hours later. Values for aspartate aminotransferase and alanine aminotransferase in serum were markedly above normal, whereas those for alkaline phosphatase and gamma-glutamyltransferase were only marginally increased. A threefold-increased creatine kinase was ascribable solely to isoenzyme CK-3, suggesting muscle breakdown. Moreover, total lactate dehydrogenase activity was increased threefold, accounted for by a ninefold increase in LD-5 isoenzyme. Those enzyme activities in serum that evidently are associated with acute hepatocellular necrosis increase quickly in hepatic infarction, and CK isoenzyme assay is a useful adjunct if LD-5 increases are significant.


Subject(s)
Infarction/enzymology , Liver/blood supply , Adult , Alanine Transaminase/analysis , Alkaline Phosphatase/analysis , Aspartate Aminotransferases/analysis , Autopsy , Creatine Kinase/analysis , Humans , Isoenzymes , L-Lactate Dehydrogenase/analysis , Male , Time Factors , gamma-Glutamyltransferase/analysis
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