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1.
Vet Pathol ; 52(1): 176-80, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24686391

ABSTRACT

A 13-week-old male intact Poodle mix dog developed an acute onset of vestibular ataxia, tetraparesis, and vomiting. The patient presented ambulatory, tetraparetic, and ataxic with a head tilt to the left and a disconjugate nystagmus (rotary nystagmus with fast phase to the right in right eye and vertical nystagmus in left eye). There were absent postural reactions in the left pelvic and left thoracic limbs and decreased right-sided postural reactions. Magnetic resonance imaging demonstrated an intra-axial mass within the left midcaudal medulla oblongata. On gross dissection, there was a left-sided neoplasm in the medulla oblongata with surrounding hemorrhage. The histologic findings indicated that the mass was a pleomorphic xanthoastrocytoma. This tumor, an uncommon variant of an astrocytoma most often seen in children and young adult humans, has yet to be described in dogs.


Subject(s)
Astrocytoma/veterinary , Brain Neoplasms/veterinary , Vestibular Diseases/veterinary , Animals , Astrocytoma/pathology , Brain Neoplasms/pathology , Dogs , Magnetic Resonance Imaging/veterinary , Male , Medulla Oblongata/pathology , Vestibular Diseases/pathology
2.
Anaesthesist ; 64(11): 846-54, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26408023

ABSTRACT

The German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft für Anästhesiologie und Intensivmedizin, DGAI) established an expert panel to develop preliminary recommendations for the application of peripheral nerve blocks on the upper extremity. The present recommendations state in different variations how ultrasound and/or electrical nerve stimulation guided nerve blocks should be performed. The description of each procedure is rather a recommendation than a guideline. The anaesthesiologist should select the variation of block which provides the highest grade of safety according to his individual opportunities. The first section comprises recommendations regarding dosages of local anaesthetics, general indications and contraindications for peripheral nerve blocks and informations about complications. In the following sections most common blocks techniques on the upper extremity are described.


Subject(s)
Anatomic Landmarks , Nerve Block , Peripheral Nerves , Ultrasonography, Interventional/methods , Upper Extremity , Humans , Peripheral Nerves/diagnostic imaging , Upper Extremity/innervation
3.
Gene ; 170(1): 113-7, 1996 Apr 17.
Article in English | MEDLINE | ID: mdl-8621070

ABSTRACT

Schizosaccharomyces pombe (Sp) rad23-1 mutant cells are extremely sensitive to UV light and ionizing radiation. A genomic DNA fragment that contains wild-type (wt) rad23 has been cloned. The DNA sequence of this cloned gene has been determined and was found to be identical to the previously characterized mating-type switching/radioresistance gene, swi10. Complementation tests between rad23-1 and swi10-154 mutant cells exclusively produce UV-sensitive progeny and confirm that these two genes are allelic. The DNA sequences of rad23-1 and swi10-154 reveal that each contains a single, unique point mutation. In rad23-1, Glu231 changes to a stop codon, resulting in the production of a truncated protein. In swi10-154, a G to A transition mutation is within a splice consensus sequence for intron 1. Therefore, the corresponding mRNA is incapable of being processed appropriately.


Subject(s)
Alleles , DNA-Binding Proteins/genetics , Endonucleases , Fungal Proteins/genetics , Proteins/genetics , Schizosaccharomyces pombe Proteins , Schizosaccharomyces/genetics , Animals , Base Sequence , Codon/genetics , DNA Mutational Analysis , DNA Repair , DNA, Fungal/genetics , Humans , Mice , Molecular Sequence Data , Mutation , Radiation Tolerance/genetics , Schizosaccharomyces/radiation effects , Sequence Homology, Nucleic Acid , Species Specificity , Ultraviolet Rays
4.
Am J Med Genet ; 83(5): 367-71, 1999 Apr 23.
Article in English | MEDLINE | ID: mdl-10232745

ABSTRACT

We report on a mother and her 5-year old son, both with a terminal deletion of the short arm of the X chromosome. By molecular genetic analysis the breakpoint was located distal to steroid sulfatase gene. The boy manifested, due to nullisomy of this region, short stature (SHOX), chondrodysplasia punctata (ARSE), and mental retardation (putative mental retardation gene MRX 49). Short stature is present in mother and son, but both also had bilateral Madelung deformity, a key finding in the Léri-Weill syndrome. We discuss the phenotype in relationship to hitherto published cases with chromosomal aberrations and contiguous gene syndromes of Xp22.3.


Subject(s)
Sex Chromosome Aberrations/diagnosis , X Chromosome , Abnormalities, Multiple/genetics , Adult , Bone and Bones/abnormalities , Child, Preschool , Chromosome Deletion , Deafness/genetics , Female , Forearm/diagnostic imaging , Homeodomain Proteins/genetics , Humans , In Situ Hybridization, Fluorescence , Male , Mental Disorders/genetics , Radiography , Seizures/genetics , Short Stature Homeobox Protein , Syndrome
5.
Chest ; 79(6): 669-71, 1981 Jun.
Article in English | MEDLINE | ID: mdl-7014127

ABSTRACT

The first two cases of Legionnaires' disease in heart transplant patients are reported. Of interest in these cases were culture of the organism from sputum, diagnosis by percutaneous lung aspiration, bronchopleural fistula formation in the first case, which was then successfully treated with multiple-tube thoracostomies, early cavitation of lesions in both cases after the start of antibiotic therapy, positive direct fluorescent antibody staining from transtracheal aspirate 42 days after starting appropriate antibiotic therapy in the first case, apparent superiority of intravenous erythromycin therapy in the first case, and survival of both patients. Our laboratory isolated and identified the organism in both cases.


Subject(s)
Heart Transplantation , Legionnaires' Disease/etiology , Transplantation/adverse effects , Adult , Erythromycin/therapeutic use , Female , Humans , Legionella/isolation & purification , Legionnaires' Disease/diagnosis , Legionnaires' Disease/drug therapy , Lung/diagnostic imaging , Lung/pathology , Male , Middle Aged , Radiography , Sputum/analysis
6.
Chest ; 106(5): 1396-400, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7956390

ABSTRACT

As previous studies have suggested that inhaled furosemide may have a protective effect against certain types of provocative challenges in asthmatic subjects, we investigated the role of furosemide in treating acute asthma exacerbations. Twenty-four patients (n = 24) with acute asthma were entered into the study on presenting to the emergency department. They were blindly randomized to receive one of three drug regimens: (1) inhaled furosemide (40 mg) (n = 8); (2) inhaled metaproterenol (15 mg) (n = 7); or (3) the combination of furosemide (40 mg) and metaproterenol (15 mg) (n = 9). We measured FEV1 at entry (time 0) and 15, 30, 45, and 60 min after inhalation of the individual drugs or the combination from a face mask nebulizer. At entry, the three groups did not differ significantly in age (mean +/- SEM = 37.6 +/- 3.6, 38.5 +/- 3.6, and 41.0 years, respectively; p = 0.770), baseline FEV1 (1.01 +/- 0.27, 1.04 +/- 0.27, and 1.25 +/- 0.14 L, respectively; p = 0.620), or theophylline levels (2.87 +/- 1.8, 7.39 +/- 2.8, and 5.29 +/- 2.6 micrograms/ml, respectively; p = 0.498). Pretreatment and posttreatment potassium levels were similar among the three groups. Inhalation of furosemide alone resulted in a 14.9 +/- 10.5 percent change in FEV1 percent from baseline, which was not statistically significant. In contrast, metaproterenol alone resulted in a 42.9 +/- 15.2 percent increase in FEV1 percent (F ratio = 6.226; p = 0.0028). The combination of furosemide and metaproterenol resulted in a change in FEV1 percent that was not statistically different compared with metaproterenol alone (FEV1 percent = 41.9 +/- 12 percent). No significant adverse effects occurred in any of the groups.


Subject(s)
Asthma/drug therapy , Furosemide/administration & dosage , Acute Disease , Administration, Inhalation , Adolescent , Adult , Analysis of Variance , Asthma/physiopathology , Drug Therapy, Combination , Forced Expiratory Volume/drug effects , Humans , Metaproterenol/administration & dosage , Middle Aged , Nebulizers and Vaporizers , Time Factors
7.
Ann Thorac Surg ; 63(4): 998-1002, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9124978

ABSTRACT

BACKGROUND: Transcranial Doppler ultrasonography detects emboli in most patients during coronary artery bypass grafting. However, the significance of these emboli has not yet been established. METHODS: We monitored 82 patients during coronary artery bypass grafting with this technique and related the numbers of emboli to the outcomes and length of hospital stay. RESULTS: We detected cerebral emboli in all patients. Patients with stroke (n = 4; 4.9%) had a mean of 449 emboli, as compared with 169 emboli in patients without stroke (n = 78) (p = 0.005). Patients with major cardiac complications (n = 7) had a mean of 392 emboli, as compared with 163 in patients without such complications (n = 75) (p = 0.003). The mean hospital stay of survivors was 8.6 days in patients with fewer than 100 emboli (n = 40), 13.5 days in patients with 101 to 300 emboli (n = 23), 16.3 days in those with 301 to 500 emboli (n = 16), and 55.8 days in patients with more than 500 emboli (n = 6) (p = 0.0007). This relation was unchanged when patients with complications were excluded. The correlation between embolization and outcome was independent of the extent of aortic atheroma or age. CONCLUSIONS: Emboli detected during coronary artery bypass grafting are significantly related to major cardiac and neurologic complications and affect length of stay in all patients, even in the absence of such specific complications.


Subject(s)
Coronary Artery Bypass , Intracranial Embolism and Thrombosis/diagnostic imaging , Length of Stay , Adult , Aged , Aged, 80 and over , Arrhythmias, Cardiac/complications , Arrhythmias, Cardiac/epidemiology , Cerebrovascular Disorders/complications , Cerebrovascular Disorders/epidemiology , Female , Humans , Intracranial Embolism and Thrombosis/complications , Intracranial Embolism and Thrombosis/epidemiology , Male , Middle Aged , Treatment Outcome , Ultrasonography
8.
Ann Thorac Surg ; 63(5): 1262-7, 1997 May.
Article in English | MEDLINE | ID: mdl-9146312

ABSTRACT

BACKGROUND: Embolic signals have been detected within both the aortic lumen and the intracranial vasculature during coronary artery bypass grafting. Total numbers of these emboli have been reported. The present study examined the size of individual emboli and the total volume of embolization. METHODS: Using transesophageal echocardiography, we continuously monitored the aortic lumen of 10 patients undergoing isolated coronary artery bypass grafting. We manually analyzed 720,000 individual echo frames over a 4-minute period after the release of aortic clamps to track and to calculate the volume of 657 individual particles. The embolic load for the entire procedure was calculated from mean volume based on analysis of 1,508 particles. We simultaneously monitored the middle cerebral artery using transcranial Doppler ultrasonography and compared numbers of emboli detected by the two techniques. RESULTS: Particle diameter ranged from 0.3 to 2.9 mm (mean, 0.8 mm), and particle volume from 0.01 to 12.5 mm3 (mean, 0.8 mm3). Twenty-eight percent of particles measured 1 mm or more, 44% measured 0.6 to 1.0 mm, and only 27% measured 0.6 mm or less in diameter. Aortic embolic load for the procedure ranged from 0.6 cm3 to 11.2 cm3 (mean, 3.7 cm3). Estimated cerebral embolic load for the procedure ranged from 60 to 510 mm3 (mean, 276 mm3). The fraction of aortic emboli entering the cerebral circulation was very variable (3.9% to 18.1%). Seventy-six percent of the embolic volume after the release of clamps occurred over a 20-second period. Only 1 patient was encephalopathic perioperatively. This patient had the largest estimated cerebral embolic load (510 mm3) and the second largest aortic embolic load (8.4 cm3). CONCLUSIONS: We determined the size of individual intraaortic embolic particles and the total volume of embolization during coronary artery bypass grafting, and found the proportion entering the cerebral circulation to be very variable. The constitution of these particles and the neurologic impairment resulting from such embolization remains to be determined.


Subject(s)
Cerebral Arteries/diagnostic imaging , Coronary Artery Bypass , Echocardiography, Transesophageal , Embolism/diagnostic imaging , Monitoring, Intraoperative , Ultrasonography, Doppler , Aged , Aged, 80 and over , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Neurologic Examination , Particle Size
9.
Ann Thorac Surg ; 64(2): 454-9, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9262593

ABSTRACT

BACKGROUND: The relation between aortic atheroma severity and stroke after coronary artery bypass grafting is established. The relation between atheroma severity and other outcome measures or numbers of emboli has not been determined. METHODS: Using transesophageal echocardiography, we determined the severity of atheroma in the ascending, arch, and descending aortic segments in 84 patients undergoing operations. Seventy patients were monitored using transcranial Doppler ultrasonography. RESULTS: The incidence of stroke was 33.3% among 9 patients with mobile plaque of the arch and 2.7% among 74 patients with nonmobile plaque (p = 0.011). Cardiac complications were not significantly related to atheroma severity in any aortic segment. Length of stay was significantly related to atheroma severity in the aortic arch (p = 0.025) and descending segment (p = 0.024). The presence of severe atheroma in both the arch and descending segments was associated with significantly longer hospital stays as compared with patients with severe atheroma in neither segment (p = 0.05). Numbers of emboli were greater in patients with severe atheroma at clamp placement, although the differences did not achieve statistical significance. CONCLUSIONS: Aortic atheroma severity is related to stroke and to the duration of hospitalization after coronary artery bypass grafting. The lack of correlation between numbers of emboli and atheroma severity suggests that m any emboli may be nonatheromatous in nature.


Subject(s)
Aortic Diseases/complications , Arteriosclerosis/complications , Coronary Artery Bypass/adverse effects , Intracranial Embolism and Thrombosis/etiology , Adult , Aged , Aged, 80 and over , Aortic Diseases/diagnostic imaging , Arteriosclerosis/diagnostic imaging , Echocardiography, Transesophageal , Female , Humans , Intracranial Embolism and Thrombosis/diagnostic imaging , Length of Stay , Male , Middle Aged , Postoperative Complications , Ultrasonography, Doppler, Transcranial
10.
Cancer Genet Cytogenet ; 130(1): 79-83, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11672779

ABSTRACT

Data concerning cytogenetic features of childhood ependymoma are rare. In this article, a gain of 1q was identified as the sole alteration in a primary childhood infratentorial ependymoma by comparative genomic hybridization (CGH). A recurrence of this brain tumor was studied using multiplex-fluorescence in situ hybridization (M-FISH) in addition to CGH and G-banding analysis. In accordance with the primary tumor, a gain of 1q corresponding to an isochromosome 1q was observed indicating an early event in the tumor development. Furthermore, M-FISH classified several other rearranged chromosomes including 6q and 17p that have previously been found to be involved in the development and progression of childhood ependymoma.


Subject(s)
Brain Neoplasms/genetics , Chromosome Aberrations , Chromosomes, Human, Pair 1 , Ependymoma/genetics , Child, Preschool , Humans , In Situ Hybridization, Fluorescence , Male
11.
J Pharm Sci ; 80(1): 50-3, 1991 Jan.
Article in English | MEDLINE | ID: mdl-2013850

ABSTRACT

The problem of optimizing ocular bioavailability of topically applied ophthalmic drugs is discussed. A formula for drug concentration in the tear film is derived using well-known pharmacokinetic relationships and a first-order drug decay model for the tear film. The time integral of the tear film concentration is then related to ocular bioavailability. The results of this analysis show that: (1) high corneal permeability (corresponding to lipophilic compounds) produces the highest bioavailability; (2) the bioavailability of drugs with high corneal permeability is relatively unaffected by drug volume; and (3) by making the dosage volume sufficiently small, a bioavailability improvement factor of approximately 4 can be obtained for drugs with low corneal permeability.


Subject(s)
Cornea/metabolism , Ophthalmic Solutions/pharmacokinetics , Administration, Topical , Biological Availability , Humans , Instillation, Drug , Mathematics , Models, Biological , Permeability
12.
J Vet Intern Med ; 5(4): 248-56, 1991.
Article in English | MEDLINE | ID: mdl-1941758

ABSTRACT

Clinical records and thoracic radiographs of 19 horses with a confirmed pathologic diagnosis of silicosis were reviewed. These horses had histories of varying degrees of chronic weight loss, exercise intolerance, and respiratory distress. At the time of presentation, two horses were asymptomatic. Ten horses were geldings and nine were female. The mean age of the 19 horses was 10.7 +/- 5.5 years. Fourteen horses were identified as being from the Monterey-Carmel Peninsula of midcoastal California. An abnormal, structured interstitial pulmonary pattern was identified on thoracic radiographs in each horse. The interstitial pulmonary changes were classified as miliary (13 horses), reticulonodular (4), or linear interstitial (2), and were best visualized dorsally and caudodorsally. In addition to the abnormal interstitial pulmonary pattern, areas of pulmonary consolidation were evident caudodorsally in seven horses. Other thoracic radiographic features included: hilar lymphadenopathy (4 horses), pleural effusion/thickening (4), cranial mediastinal lymphadenopathy (2), hyperinflation (1), and a discrete pulmonary mass (1). Necropsy findings in eight horses and results of lung biopsies in an additional five horses showed a diffuse, multifocal, granulomatous pneumonia with areas of pulmonary fibrosis. Cellular infiltrates included predominantly macrophages with intracellular and/or extracellular crystalline material, occasional lymphocytes, and giant cells. Similar cellular changes were also identified, during necropsy, in the hilar and tracheobronchial lymph nodes in each of the eight horses, although gross enlargement of the lymph nodes was present in only six horses. The radiographic and pathologic findings of these 19 horses are consistent with chronic or the accelerated forms of silicosis that are recognized in humans.


Subject(s)
Horse Diseases/diagnostic imaging , Lung/diagnostic imaging , Silicosis/veterinary , Animals , California , Female , Horses , Male , Radiography , Retrospective Studies , Silicosis/diagnostic imaging
13.
J Am Vet Med Assoc ; 189(3): 309-10, 1986 Aug 01.
Article in English | MEDLINE | ID: mdl-3744991

ABSTRACT

An ectopic ureter extending to the urinary bladder and to the proximal portion of the urethra was diagnosed in a 6-month-old dog with urinary incontinence. The diagnosis was made by use of excretory urography. The kidney and ureter were removed. When urinary incontinence continued, positive-contrast cystography was performed. The ectopic ureter was found to bypass the bladder via a submucosal extension that emptied into the urethra.


Subject(s)
Dog Diseases/diagnosis , Ureter/abnormalities , Urinary Incontinence/veterinary , Animals , Dog Diseases/diagnostic imaging , Dogs , Female , Kidney/abnormalities , Radiography , Ureter/diagnostic imaging , Urethra/abnormalities , Urinary Bladder/abnormalities , Urinary Incontinence/diagnosis , Urinary Incontinence/diagnostic imaging
14.
J Am Vet Med Assoc ; 192(11): 1597-603, 1988 Jun 01.
Article in English | MEDLINE | ID: mdl-3410781

ABSTRACT

The echocardiographic (M-mode and 2-dimensional) features (before and after pericardiocentesis) of 4 dogs with pericardial effusion and clinical evidence of cardiac tamponade were reviewed. M-Mode echocardiography revealed pericardial effusion, with exaggerated swinging motion of the heart and abnormal septal motion in all 4 dogs. In each case, 2-dimensional echocardiography demonstrated right ventricular diastolic free-wall collapse. Three dogs had right atrial diastolic collapse as well. Clinical signs improved, and right ventricular and right atrial diastolic collapse subsided after pericardiocentesis. Two-dimensional echocardiographic features of right atrial and ventricular collapse were used as indicators for determining the presence of cardiac tamponade.


Subject(s)
Cardiac Tamponade/veterinary , Dog Diseases/diagnosis , Echocardiography/veterinary , Pericardial Effusion/veterinary , Animals , Cardiac Tamponade/diagnosis , Cardiac Tamponade/therapy , Dog Diseases/therapy , Dogs , Drainage/veterinary , Pericardial Effusion/diagnosis , Pericardial Effusion/therapy , Retrospective Studies
15.
J Am Vet Med Assoc ; 196(9): 1479-82, 1990 May 01.
Article in English | MEDLINE | ID: mdl-2187840

ABSTRACT

Ejaculate, urine, urethral swab specimens, and ultrasonography-guided small-needle prostatic cyst aspiration and/or tissue core biopsy specimens were collected for bacteriologic culture from 25 dogs in which prostatic disease was suspected on the basis of history, clinical signs of disease, or results of physical examination. The prostate gland in each dog was examined ultrasonographically, and the tissue core biopsy specimens were examined histologically and bacteriologically. Two methods were used to assess bacterial prostatitis. In 5 dogs (20%), bacteriologic culture results of paired urethral swab and ejaculate specimens differed from culture results of specimens obtained by needle aspiration of prostatic cyst fluid or tissue core biopsy. The prostate gland in 17 dogs had 1 or more cystic, fluid-filled structures (0.5 to 4.0 cm in diameter). Ultrasonographic appearance of the prostate gland did not have obvious correlation with culture results from dogs of the study. Histologic results of prostatic tissue core biopsy specimens correlated well with culture results.


Subject(s)
Bacterial Infections/veterinary , Dog Diseases/microbiology , Prostate/microbiology , Prostatitis/veterinary , Specimen Handling/veterinary , Animals , Bacterial Infections/microbiology , Bacterial Infections/pathology , Biopsy/veterinary , Biopsy, Needle/veterinary , Colony Count, Microbial , Dog Diseases/pathology , Dogs , Male , Prostate/pathology , Prostatitis/microbiology , Prostatitis/pathology , Semen/microbiology , Ultrasonography/veterinary
16.
Vet Clin North Am Small Anim Pract ; 15(6): 1123-48, 1985 Nov.
Article in English | MEDLINE | ID: mdl-3909607

ABSTRACT

Focal hepatic and splenic lesions, vascular abnormalities, and disorders of the biliary system can readily be detected with ultrasonography. The sonographic appearance in certain cases may be nonspecific, but the differential diagnosis can be substantially narrowed when the presenting clinical signs are considered. Ultrasonography is less helpful when the liver or spleen is diffusely involved without parenchymal abnormalities. However, certain diseases may also be eliminated from diagnostic consideration on the basis of this finding. Percutaneous ultrasound guided biopsy markedly improves the success and safety of obtaining a definitive diagnosis when either diffuse or focal lesions are present. Sonography has also been very beneficial for serially evaluating the response to therapy once focal lesions of the liver or spleen have been identified.


Subject(s)
Gallbladder Diseases/veterinary , Liver Diseases/veterinary , Splenic Diseases/veterinary , Ultrasonography/veterinary , Animals , Dogs , Female , Gallbladder/anatomy & histology , Gallbladder/pathology , Gallbladder Diseases/diagnosis , Liver/anatomy & histology , Liver/pathology , Liver Diseases/diagnosis , Male , Spleen/anatomy & histology , Spleen/pathology , Splenic Diseases/diagnosis
17.
Chemosphere ; 93(9): 1655-64, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23856466

ABSTRACT

'Naphthenic acids' (NAs) in petroleum produced water and oil sands process water (OSPW), have been implicated in toxicological effects. However, many are not well characterized. A method for fractionation of NAs of an OSPW was used herein and a multi-method characterization of the fractions conducted. The unfractionated OSPW acidic extract was characterized by elemental analysis, electrospray ionization-Orbitrap-mass spectrometry (ESI-MS), and an esterified extract by Fourier Transform infrared (FTIR) and ultraviolet-visible (UV) absorption spectroscopy and by comprehensive multidimensional gas chromatography-MS (GCxGC-MS). Methyl esters were fractionated by argentation solid phase extraction (Ag(+) SPE) and fractions eluting with: hexane; diethyl ether: hexane and diethyl ether, examined. Each was weighed, examined by elemental analysis, FTIR, UV, GC-MS and GCxGC-MS (both nominal and high resolution MS). The ether fraction, containing sulfur, was also examined by GCxGC-sulfur chemiluminescence detection (GCxGC-SCD). The major ions detected by ESI-MS in the OSPW extract were assigned to alicyclic and aromatic 'O2' acids; sulfur was also present. Components recovered by Ag(+) SPE were also methyl esters of alicyclic and aromatic acids; these contained little sulfur or nitrogen. FTIR spectra showed that hydroxy acids and sulfoxides were absent or minor. UV spectra, along with the C/H ratio, further confirmed the aromaticity of the hexane:ether eluate. The more minor ether eluate contained further aromatics and 1.5% sulfur. FTIR spectra indicated free carboxylic acids, in addition to esters. Four major sulfur compounds were detected by GCxGC-SCD. GCxGC-high resolution MS indicated these were methyl esters of C18 S-containing, diaromatics with ≥C3 carboxylic acid side chains.


Subject(s)
Carboxylic Acids/analysis , Oil and Gas Fields , Petroleum/analysis , Water Pollutants, Chemical/analysis , Carboxylic Acids/chemistry , Chemical Fractionation , Gas Chromatography-Mass Spectrometry , Solid Phase Extraction , Spectrometry, Mass, Electrospray Ionization , Water Pollutants, Chemical/chemistry
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