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1.
Aust Vet J ; 100(6): 271-276, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35257364

ABSTRACT

BACKGROUND: Neoplasia is considered to be rare in macropods. Anaplastic thyroid carcinoma (ATC) also known as undifferentiated or giant cell carcinoma, is a rare but aggressive and lethal solid tumour reported to affect humans, dogs, cats, racoons and birds. It is derived from poorly differentiated follicular cells and lacks the characteristic architectural pattern of arrangement of tumour cells. ATC has not previously been reported in macropods. CASE REPORT: A brush-tailed rock-wallaby (Petrogale penicillata) was presented for a mass on the ventral neck. A clinical diagnosis of thyroid carcinoma was suspected based on radiology, ultrasound and cytology. Other than palliative care, treatment was declined. Four months later the wallaby was found dead and submitted for necropsy. Gross examination and histopathology demonstrated a unilateral ATC with vascular neoplastic emboli and distant metastases to the heart, lungs and liver. CONCLUSION: The clinical signs associated with thyroid tumours may be the result of localised growth and expansion of the thyroid, metastatic disease or a combination of these effects. Most thyroid tumours are nonfunctional. Based on the lack of typical clinical signs associated with functional thyroid tumours, in this case, we conclude that the thyroid tumour in this wallaby was likely to be nonfunctional. The cause of death in this wallaby was likely due to the heavy tumour burden with compromised cardiorespiratory function exacerbated by dorsoventral compression of the larynx. More study is needed to better understand thyroid neoplasia in macropods.


Subject(s)
Thyroid Carcinoma, Anaplastic , Thyroid Neoplasms , Animals , Macropodidae , Thyroid Carcinoma, Anaplastic/diagnosis , Thyroid Carcinoma, Anaplastic/pathology , Thyroid Carcinoma, Anaplastic/veterinary , Thyroid Neoplasms/diagnostic imaging , Thyroid Neoplasms/veterinary
2.
Aust Vet J ; 98(8): 411-416, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32761617

ABSTRACT

OBJECTIVE: To assess the efficacy of an herbal spray combining various essential oils, with a claim of mast cell stabilisation, antipruritic, anti-inflammatory, and insect repellent effects on the clinical presentation of insect bite hypersensitivity (IBH) in horses. DESIGN: Double-blinded, placebo-controlled, randomised, cross-over clinical trial. METHODS: Twenty adult horses with clinical IBH were treated with a daily application of herbal spray or placebo for 28 days in a randomised, cross-over fashion, separated by a>28-day washout period. Horses were examined and scored prior to and after the completion of each treatment. Histopathology was performed on four horses. Owners kept daily diaries of observations. RESULTS: The herbal spray significantly reduced the severity of all assessed parameters (pruritus, excoriations, lichenification and alopecia; P < 0.05) compared with baseline values (pretreatment) and with placebo. Owners reported improvement of pruritus in 19/20 horses (95%) with complete resolution in 17 horses (85%) following treatment. Skin biopsies showed resolution of orthokeratosis in 4/4 horses, reduced thickness of the stratum spinosum in 2/4 horses and complete resolution of histopathological abnormalities in 1/4 horses after treatment, compared with either no change or deterioration of histopathologic lesions after placebo. No side effects were observed. CONCLUSIONS: The tested herbal spray may be an effective treatment for the management of equine IBH.


Subject(s)
Ceratopogonidae , Horse Diseases , Hypersensitivity/veterinary , Insect Bites and Stings/veterinary , Oils, Volatile , Animals , Horses
3.
Bone Joint Res ; 6(11): 612-618, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29092816

ABSTRACT

OBJECTIVES: This study looked to analyse the expression levels of microRNA-140-3p and microRNA-140-5p in synovial fluid, and their correlations to the severity of disease regarding knee osteoarthritis (OA). METHODS: Knee joint synovial fluid samples were collected from 45 patients with OA of the knee (15 mild, 15 moderate and 15 severe), ten healthy volunteers, ten patients with gouty arthritis, and ten with rheumatoid arthritis. The Kellgren-Lawrence grading (KLG) was used to assess the radiological severity of knee OA, and the patients were stratified into mild (KLG < 2), moderate (KLG = 2), and severe (KLG > 2). The expression of miR-140-3p and miR-140-5p of individual samples was measured by SYBR Green quantitative polymerase chain reaction (PCR) analysis. The expression of miR-140-3p and miR-140-5p was normalised to U6 internal control using the 2-△△CT method. All data were processed using SPSS software. RESULTS: Expression of both miR-140-3p and miR-140-5p was downregulated in OA synovial fluid, showing a statistical difference between the OA and non-OA group, and increased OA severity was associated with a decreased expression of miR-140-3p or miR-140-5p. The Spearman rank correlation analysis suggested that the expression of miR-140-3p or miR-140-5p was negatively correlated with OA severity. In addition, the expression of miR-140-5p was 7.4 times higher than that of miR-140-3p across all groups. CONCLUSION: The dysregulation of miR-140-3p and miR-140-5p in synovial fluid and their correlations with the disease severity of OA may provide an important experimental basis for OA classification, and the miR-140-3p/miR-140-5p are of great potential as biomarkers in the diagnosis and clinical management of patients with OA.Cite this article: C-M. Yin, W-C-W. Suen, S. Lin, X-M. Wu, G. Li, X-H. Pan. Dysregulation of both miR-140-3p and miR-140-5p in synovial fluid correlate with osteoarthritis severity. Bone Joint Res 2017;6:612-618. DOI: 10.1302/2046-3758.611.BJR-2017-0090.R1.

4.
Aust Vet J ; 95(8): 299-303, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28749026

ABSTRACT

CASE REPORT: A 6-week-old Thoroughbred filly was presented for evaluation of an expansile mass overlying the right nasal passage and causing respiratory stertor. On skull radiographs, there was a loculated, soft tissue-opaque mass identified dorsal to the right upper premolars and effacing the right nasal cavity. Computed tomography (CT) revealed a locally extensive mass with relatively benign characteristics located centrally on the tooth root apices of the deciduous second premolar (506). The mass extended axially into the right nasal cavity, occluding the meatuses and causing displacement of the nasal septum to the left. CLINICAL OUTCOME & SIGNIFICANCE: Surgical excision was not deemed feasible with an athletic future in mind and the owners elected to euthanase the filly. Histopathologically, the mass was consistent with unicystic ameloblastoma and was lined intermittently with palisading, columnar basal cells (ameloblast-like cells) overlying a zone containing stellate cells in loose stroma. To the authors' knowledge this is the first report of a CT scan of an equine ameloblastoma. Although histopathology was essential for definitive diagnosis, CT clearly defined the origin of the mass and identified its locally extensive, cystic nature, which enabled informed decisions to be made.


Subject(s)
Ameloblastoma/veterinary , Maxillary Neoplasms/veterinary , Tomography, X-Ray Computed/veterinary , Ameloblastoma/diagnosis , Animals , Female , Horses , Maxillary Neoplasms/diagnosis
5.
J Clin Pathol ; 56(9): 713-4, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12944560

ABSTRACT

Malignant extrarenal rhabdoid tumour (MERT) of the gastrointestinal tract is rarely reported in the literature. This report describes the clinical and pathological features of a malignant rhabdoid tumour of the oesophagus in a Chinese man. Ivor-Lewis oesophagectomy had been performed. The tumour behaved aggressively and the patient died from disseminated malignancy one year later. This is only the second case report of a malignant rhabdoid tumour affecting the oesophagus.


Subject(s)
Esophageal Neoplasms/pathology , Rhabdoid Tumor/pathology , Esophageal Neoplasms/surgery , Fatal Outcome , Humans , Male , Microscopy, Electron , Middle Aged , Rhabdoid Tumor/surgery
6.
Infect Immun ; 68(5): 2948-53, 2000 May.
Article in English | MEDLINE | ID: mdl-10768993

ABSTRACT

Mycobacterium bovis bacillus Calmette-Guérin (BCG) is the only vaccine approved for prevention of tuberculosis. It has been postulated that serial passage of BCG over the years may have resulted in attenuation of its effectiveness. Because interleukin-12 (IL-12) and oligodeoxynucleotides (ODN) containing cytidine phosphate guanosine (CpG) motifs have been shown to enhance Th1 responses in vivo, they were chosen as adjuvants to increase the effectiveness of BCG vaccination. In this report, mice were vaccinated with BCG with or without IL-12 or CpG ODN and then challenged 6 weeks later via the aerosol route with the Erdman strain of M. tuberculosis. Mice vaccinated with BCG alone showed a 1- to 2-log reduction in bacterial load compared with control mice that did not receive any vaccination prior to M. tuberculosis challenge. Moreover, the bacterial loads of mice vaccinated with BCG plus IL-12 or CpG ODN were a further two- to fivefold lower than those of mice vaccinated with BCG alone. As an immune correlate, the antigen-specific production IFN-gamma and mRNA expression in spleen cells prior to challenge were evaluated. Mice vaccinated with BCG plus IL-12 or CpG ODN showed enhanced production of IFN-gamma compared with mice vaccinated with BCG alone. Finally, granulomas in BCG-vaccinated mice were smaller and more lymphocyte rich than those in unvaccinated mice; however, the addition of IL-12 or CpG ODN to BCG vaccination did not alter granuloma formation or result in added pulmonary damage. These observations support a role for immune adjuvants given with BCG vaccination to enhance its biologic efficacy.


Subject(s)
Adjuvants, Immunologic , BCG Vaccine/immunology , CpG Islands/immunology , Interleukin-12/immunology , Mycobacterium tuberculosis/immunology , Oligodeoxyribonucleotides/immunology , Administration, Inhalation , Animals , Interferon-gamma/biosynthesis , Lung/microbiology , Lung/pathology , Mice , Mice, Inbred BALB C , Mycobacterium tuberculosis/pathogenicity , Tuberculosis/pathology , Tuberculosis/prevention & control , Vaccination , Virulence
7.
Proc Natl Acad Sci U S A ; 96(8): 4500-5, 1999 Apr 13.
Article in English | MEDLINE | ID: mdl-10200291

ABSTRACT

UV resonance Raman spectroscopy was used to detect and estimate the frequency of the unfavored imino tautomer of the transition mutagen 5-hydroxy-2'-deoxycytidine (HO5dCyt) in its anionic form. In DNA, this 2'-deoxycytidine analog arises from the oxidation of 2'-deoxycytidine and induces C --> T transitions with 10(2) greater frequency than such spontaneous transitions. An imino tautomer marker carbonyl band (approximately 1650 cm-1) is enhanced at approximately 65 degrees C against an otherwise stable spectrum of bands associated with the favored amino tautomer. This band is similarly present in the UV resonance Raman spectra of the imino cytidine analogs N3-methylcytidine at high pH and N4-methoxy-2'-deoxycytidine at pH 7 and displays features attributable to the imino form of C residues and their derivatives. The fact that the imino tautomer of HO5dCyt occurs at a frequency consistent with its high mutagenic enhancement lends strong support to the hypothesis that unfavored base tautomers play important roles in the mispair intermediates of replication leading to substitution mutations.


Subject(s)
Deoxycytidine/analogs & derivatives , Mutagens/analysis , DNA/chemistry , Deoxycytidine/analysis , Deoxycytidine/chemistry , Hydrogen Bonding , Hydrogen-Ion Concentration , Imines/analysis , Imines/chemistry , Mutagens/chemistry , Solvents , Spectrophotometry, Ultraviolet/methods , Spectrum Analysis, Raman/methods , Stereoisomerism , Structure-Activity Relationship , Thermodynamics
8.
J Bacteriol ; 181(3): 965-72, 1999 Feb.
Article in English | MEDLINE | ID: mdl-9922262

ABSTRACT

2,4,5-Trihydroxytoluene (THT) oxygenase from Burkholderia sp. strain DNT catalyzes the conversion of THT to an unstable ring fission product. Biochemical and genetic studies of THT oxygenase were undertaken to elucidate the mechanism of the ring fission reaction. The THT oxygenase gene (dntD) was previously localized to the 1.2-kb DNA insert subcloned in the recombinant plasmid designated pJS76 (W. C. Suen and J. C. Spain, J. Bacteriol. 175:1831-1837, 1993). Analysis of the deduced amino acid sequence of DntD revealed the presence of the highly conserved residues characteristic of the catechol 2,3-dioxygenase gene family I. The deduced amino acid sequence of DntD corresponded to a molecular mass of 35 kDa. The native molecular masses for the THT oxygenase estimated by using gel filtration chromatography and nondenaturing gel electrophoresis were 67.4 and 77.8 kDa, respectively. The results suggested that the native protein consists of two identical subunits. The colorless protein contained 2 mol of iron per mol of protein. Stimulation of activity in the presence of ferrous iron and ascorbate suggested a requirement for ferrous iron in the active site. The properties of the enzyme are similar to those of the catechol 2,3-dioxygenases (meta-cleavage dioxygenases). In addition to THT, the enzyme exhibited activity towards 1,2,4-benzenetriol, catechol, 3- and 4-methylcatechol, and 3- and 4-chlorocatechol. The chemical analysis of the THT ring cleavage product showed that the product was 2, 4-dihydroxy-5-methyl-6-oxo-2,4-hexadienoic acid, consistent with extradiol ring fission of THT.


Subject(s)
Burkholderia/enzymology , Burkholderia/genetics , Oxygenases/metabolism , Toluene/analogs & derivatives , Amino Acid Sequence , Base Sequence , Chromatography, Gel , Chromatography, Ion Exchange , Cloning, Molecular , Evolution, Molecular , Kinetics , Molecular Sequence Data , Molecular Weight , Oxygenases/chemistry , Oxygenases/genetics , Phylogeny , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Sequence Alignment , Sequence Homology, Amino Acid , Toluene/metabolism
9.
Angiology ; 49(10): 789-800, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9783643

ABSTRACT

Acute renal failure (ARF) is one of the major complications after cardiopulmonary bypass for open heart operations. The present study was undertaken to identify the risk factors for the development of ARF following cardiopulmonary bypass (CPB). Four hundred and forty-seven consecutive patients who underwent open heart procedures from July 1994 to June 1995 were analyzed retrospectively. Their mean age was 55.6 +/- 14.2 (SD) years (range, 18 to 80). Dialysis was instituted whenever a patient exhibited inadequate urine output (<0.5 mL/kg/hr) for 2 to 3 hours despite correction of hemodynamic status and diuretic therapy, especially if fluid overload, hyperkalemia, or metabolic acidosis were also present. Twenty variables were analyzed by univariate analysis; these included nine preoperative variables--age, sex, hypertension, atherosclerosis, diabetes mellitus, left ventricular end-diastolic dimension (LVEDD) >5 cm, preoperative congestive heart failure, renal insufficiency (serum creatinine > or =130 micromol/L on two occasions), and sepsis--10 intraoperative variables--duration of CPB, redo procedures, emergency surgery, use of intraaortic balloon pump (IABP) in operating room, use of gentamicin, use of ceftriaxone, use of sulbactam/ampicillin, requirement of deep hypothermic circulatory arrest, duration of low mean perfusion pressure (mean pressure <50 mmHg for more than 30 minutes), operation on multiple valves--and one postoperative variable--significant hypotension (systolic blood pressure less than 90 mmHg for more than 1 hour). Significant variables or the variables having a trend (p<0.1) to be associated with ARF were included in stepwise multiple logistic regression analyses. Three regression analyses were performed separately. The incidence of ARF requiring dialysis in the study period was 15.0%. Significant risk factors for whole group of patients (regression I) were preoperative renal insufficiency (p<0.0001), postoperative hypotension (p<0.0001), cardiopulmonary bypass time more than 140 min (p<0.005), preoperative congestive heart failure (p<0.01), and history of diabetes mellitus (p<0.01). The risk factors in the valve group of patients (regression II) were preoperative renal insufficiency (p<0.0001) and postoperative hypotension (p<0.05). Risk factors in the CABG patients (regression III) were postoperative hypotension (p=0.0001), CPB time more than 140 min (p<0.05), preoperative renal insufficiency (p<0.05), and age (p<0.05). The authors conclude that preoperative renal insufficiency and postoperative hypotension are the most important independent risk factors for ARF in postcardiac surgical patients. In addition, CPB time greater than 140 minutes and old age are also independent risk factors for ARF in CABG patients. CPB time more than 140 minutes, history of diabetes mellitus, and preoperative congestive heart failure are independent risk factors for development of ARF in our total group of patients. These findings may have important clinical implications in the prevention of ARF in postcardiac surgical patients.


Subject(s)
Acute Kidney Injury/etiology , Cardiac Surgical Procedures , Cardiopulmonary Bypass/adverse effects , Acute Kidney Injury/physiopathology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Blood Pressure , Humans , Logistic Models , Middle Aged , Multivariate Analysis , Peritoneal Dialysis , Retrospective Studies , Risk Factors , Time Factors
10.
J Exp Med ; 186(8): 1233-40, 1997 Oct 20.
Article in English | MEDLINE | ID: mdl-9334362

ABSTRACT

The lymphotoxin (LT)/tumor necrosis factor (TNF) family has been implicated in the neurologic inflammatory diseases multiple sclerosis (MS) and experimental allergic encephalomyelitis (EAE). To determine the role of individual family members in EAE, C57BL/6 mice, LT-alpha-deficient (LT-alpha-/- mice), or LT-beta-deficient (LT-beta-/- mice), and their wild-type (WT) littermates were immunized with rat myelin oligodendrocyte glycoprotein (MOG) peptide 35-55. C57BL/6 and WT mice developed chronic, sustained paralytic disease with average maximum clinical scores of 3.5 and disease indices (a measure of day of onset and sustained disease scores) ranging from 367 to 663 with central nervous system (CNS) inflammation and demyelination. LT-alpha-/- mice were primed so that their splenic lymphocytes proliferated in response to MOG 35-55 and the mice produced anti-MOG antibody. However, LT-alpha-/- mice were quite resistant to EAE with low average clinical scores (<1), an average disease index of 61, and the negligible CNS inflammation and demyelination. WT T cells transferred EAE to LT-alpha-/- recipients. LT-beta-/- mice were susceptible to EAE, though less than WT, with an average maximum clinical score of 1.9 and disease index of 312. These data implicate T cell production of LT-alpha in MOG EAE and support a major role for LT-alpha3, a minor role for the LT-alpha/beta complex, and by inference, no role for TNF-alpha.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental/immunology , Lymphotoxin-alpha/physiology , Amino Acid Sequence , Animals , Brain/pathology , Encephalomyelitis, Autoimmune, Experimental/pathology , Encephalomyelitis, Autoimmune, Experimental/prevention & control , Lymphotoxin-alpha/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Molecular Sequence Data , Myelin Proteins , Myelin-Associated Glycoprotein/immunology , Myelin-Oligodendrocyte Glycoprotein , Oligodendroglia/immunology , Spinal Cord/pathology , Vaccination
11.
J Popul Econ ; 10(4): 443-61, 1997.
Article in English | MEDLINE | ID: mdl-12293087

ABSTRACT

"This paper provides an overview of retirement patterns in Hong Kong on the basis of limited data. A censored regression model is used to infer the retirement age from people's current retirement status and their current age. This model is equivalent to a restricted probit model, and the interpretation of parameters is straightforward. The results clearly show a negative income effect on the retirement decision. The retirement age seems to be positively related to lifetime earnings but negatively related to the rate of decline of earnings with age."


Subject(s)
Age Factors , Income , Models, Theoretical , Retirement , Asia , Demography , Developing Countries , Economics , Employment , Asia, Eastern , Hong Kong , Population , Population Characteristics , Research , Social Class , Socioeconomic Factors
12.
J Bacteriol ; 178(20): 6019-24, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8830701

ABSTRACT

4-Methyl-5-nitrocatechol (MNC) is an intermediate in the degradation of 2,4-dinitrotoluene by Burkholderia sp. strain DNT. In the presence of NADPH and oxygen, MNC monooxygenase catalyzes the removal of the nitro group from MNC to form 2-hydroxy-5-methylquinone. The gene (dntB) encoding MNC monooxygenase has been previously cloned and characterized. In order to examine the properties of MNC monooxygenase and to compare it with other enzymes, we sequenced the gene encoding the MNC monooxygenase and purified the enzyme from strain DNT. dntB was localized within a 2.2-kb ApaI DNA fragment. Sequence analysis of this fragment revealed an open reading frame of 1,644 bp with an N-terminal amino acid sequence identical to that of purified MNC monooxygenase from strain DNT. Comparison of the derived amino acid sequences with those of other genes showed that DntB contains the highly conserved ADP and flavin adenine dinucleotide (FAD) binding motifs characteristic of flavoprotein hydroxylases. MNC monooxygenase was purified to homogeneity from strain DNT by anion exchange and gel filtration chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed a single protein with a molecular weight of 60,200, which is consistent with the size determined from the gene sequence. The native molecular weight determined by gel filtration was 65,000, which indicates that the native enzyme is a monomer. It used either NADH or NADPH as electron donors, and NADPH was the preferred cofactor. The purified enzyme contained 1 mol of FAD per mol of protein, which is also consistent with the detection of an FAD binding motif in the amino acid sequence of DntB. MNC monooxygenase has a narrow substrate specificity. MNC and 4-nitrocatechol are good substrates whereas 3-methyl-4-nitrophenol, 3-methyl-4-nitrocatechol, 4-nitrophenol, 3-nitrophenol, and 4-chlorocatechol were not. These studies suggest that MNC monooxygenase is a flavoprotein that shares some properties with previously studied nitrophenol oxygenases.


Subject(s)
Bacterial Proteins/genetics , Burkholderia/genetics , Flavoproteins/genetics , Oxygenases/genetics , Adenosine Diphosphate , Amino Acid Sequence , Base Sequence , Binding Sites , Biodegradation, Environmental , Burkholderia/enzymology , Dinitrobenzenes/metabolism , Flavin-Adenine Dinucleotide/analysis , Flavoproteins/isolation & purification , Genes, Bacterial , Molecular Sequence Data , Oxygenases/isolation & purification , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Substrate Specificity
13.
J Bacteriol ; 178(16): 4926-34, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8759857

ABSTRACT

2,4-Dinitrotoluene (DNT) dioxygenase from Burkholderia sp. strain DNT catalyzes the initial oxidation of DNT to form 4-methyl-5-nitrocatechol (MNC) and nitrite. The displacement of the aromatic nitro group by dioxygenases has only recently been described, and nothing is known about the evolutionary origin of the enzyme systems that catalyze these reactions. We have shown previously that the gene encoding DNT dioxygenase is localized on a degradative plasmid within a 6.8-kb NsiI DNA fragment (W.-C. Suen and J. C. Spain, J. Bacteriol. 175:1831-1837, 1993). We describe here the sequence analysis and the substrate range of the enzyme system encoded by this fragment. Five open reading frames were identified, four of which have a high degree of similarity (59 to 78% identity) to the components of naphthalene dioxygenase (NDO) from Pseudomonas strains. The conserved amino acid residues within NDO that are involved in cofactor binding were also identified in the gene encoding DNT dioxygenase. An Escherichia coli clone that expressed DNT dioxygenase converted DNT to MNC and also converted naphthalene to (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene. In contrast, the E. coli clone that expressed NDO did not oxidize DNT. Furthermore, the enzyme systems exhibit similar broad substrate specificities and can oxidize such compounds as indole, indan, indene, phenetole, and acenaphthene. These results suggest that DNT dioxygenase and the NDO enzyme system share a common ancestor.


Subject(s)
Burkholderia/enzymology , Multienzyme Complexes/metabolism , Oxygenases/metabolism , Amino Acid Sequence , Base Sequence , Burkholderia/genetics , Cloning, Molecular , Dioxygenases , Escherichia coli , Genes, Bacterial , Kinetics , Molecular Sequence Data , Oxygenases/biosynthesis , Oxygenases/isolation & purification , Recombinant Proteins/biosynthesis , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid , Substrate Specificity
14.
J Laryngol Otol ; 108(12): 1102-4, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7861095

ABSTRACT

Tumours of the parapharyngeal space are not common. The majority arise from the deep lobe of the parotid gland or neurovascular structures. We describe a case of fibromatosis, which has not previously been reported at this site.


Subject(s)
Fibroma/pathology , Pharyngeal Neoplasms/pathology , Adult , Fibroma/surgery , Humans , Male , Pharyngeal Neoplasms/surgery , Tomography, X-Ray Computed
15.
Gene ; 143(1): 67-71, 1994 May 27.
Article in English | MEDLINE | ID: mdl-8200540

ABSTRACT

Pseudomonas sp. strain NCIB 9816-4 utilizes naphthalene dioxygenase (NDO), a multicomponent enzyme system, to initiate naphthalene degradation. The terminal component of NDO is an iron-sulfur protein (ISPNAP) with an alpha 2 beta 2 subunit composition. The structural genes encoding the alpha (nahAc) and beta (nahAd) subunits were cloned separately and together into expression vectors where transcription is under the control of the T7 promoter. The recombinant plasmids were transformed into Escherichia coli JM109[pGP1-2] and the synthesis of ISPNAP and its alpha and beta subunits was determined by SDS-PAGE. Low expression of nahAd was shown to be due to inefficient initiation of translation, but a sixfold increase in the amount of beta subunit synthesized was achieved in a coupled translation system. Inclusion bodies were found in all recombinants. Increased levels of soluble active proteins were obtained when E. coli JM109(DE3), used as the host strain for recombinant plasmid, was grown at 25 degrees C. ISPNAP from JM109(DE3)[pDTG121] was purified to homogeneity and shown to have the same properties as those determined for the enzyme purified from NCIB 9816-4. Active ISPNAP was also obtained by mixing cell extracts from separate strains that synthesized the alpha and beta subunits. The availability of large amounts of purified ISPNAP and its alpha and beta subunits will facilitate future studies on the mechanism of oxygen fixation by NDO.


Subject(s)
Bacterial Proteins/biosynthesis , Escherichia coli/enzymology , Genes, Bacterial , Iron-Sulfur Proteins/chemistry , Multienzyme Complexes/biosynthesis , Oxygenases/biosynthesis , Bacterial Proteins/genetics , Bacteriophage T7 , Base Sequence , Cloning, Molecular , DNA Transposable Elements , Dioxygenases , Electrophoresis, Polyacrylamide Gel , Escherichia coli/genetics , Genetic Engineering/methods , Molecular Sequence Data , Multienzyme Complexes/chemistry , Multienzyme Complexes/genetics , Oxygenases/chemistry , Oxygenases/genetics , Peptide Fragments/genetics , Plasmids , Protein Biosynthesis , Recombinant Fusion Proteins/biosynthesis
16.
J Bacteriol ; 175(18): 5877-81, 1993 Sep.
Article in English | MEDLINE | ID: mdl-8376335

ABSTRACT

The terminal oxygenase component (ISPNAP) of naphthalene dioxygenase from Pseudomonas putida NCIB 9816-4 was purified to homogeneity. The protein contained approximately 4 g-atoms each of iron and acid-labile sulfide per mol of ISPNAP, and enzyme activity was stimulated significantly by addition of exogenous iron. The large (alpha) and small (beta) subunits of ISPNAP were isolated by two different procedures. The NH2-terminal amino acid sequences of the alpha and beta subunits were identical to the deduced amino acid sequences reported for the ndoB and ndoC genes from P. putida NCIB 9816 and almost identical to the NH2-terminal amino acid sequences determined for the large and small subunits of ISPNAP from P. putida G7. Gel filtration in the presence of 6 M urea gave an alpha subunit with an absorption maximum at 325 nm and broad absorption between 420 and 450 nm. The alpha subunit contained approximately 2 g-atoms each of iron and acid-labile sulfide per mol of the subunit. The beta subunit did not contain iron or acid-labile sulfide. These results, taken in conjunction with the deduced amino acid sequences of the large subunits from several iron-sulfur oxygenases, indicate that each alpha subunit of ISPNAP contains a Rieske [2Fe-2S] center.


Subject(s)
Multienzyme Complexes/metabolism , Oxygenases/metabolism , Pseudomonas putida/enzymology , Dioxygenases , Electrophoresis, Polyacrylamide Gel , Multienzyme Complexes/genetics , Multienzyme Complexes/isolation & purification , Oxygenases/genetics , Oxygenases/isolation & purification , Spectrum Analysis
17.
Gene ; 127(1): 31-7, 1993 May 15.
Article in English | MEDLINE | ID: mdl-8486285

ABSTRACT

The multicomponent enzyme, naphthalene dioxygenase, initiates the metabolism of naphthalene by Pseudomonas putida strains G7 (PpG7) and NCIB 9816-4 (Pp9816-4). The genes involved (nahAaAbAcAd) are encoded by the NAH7 and pDTG1 plasmids, respectively, and form part of the nah operon. The locations of the structural genes were determined on previously cloned fragments of DNA. The nucleotide (nt) sequences were determined for nahAaAb from Pp9816-4 and for nahAaAbAcAd from PpG7. The appropriate open reading frames were identified using N-terminal amino acid sequences determined from the purified proteins. The two nt sequences showed 93% homology, with the least homology seen upstream from the promoter region.


Subject(s)
Genes, Bacterial , Multienzyme Complexes/genetics , Oxygenases/genetics , Pseudomonas putida/genetics , Amino Acid Sequence , Base Sequence , Cloning, Molecular , DNA, Bacterial , Dioxygenases , Exons , Molecular Sequence Data , Multienzyme Complexes/metabolism , Oxygenases/metabolism , Pseudomonas putida/enzymology , Restriction Mapping
18.
J Bacteriol ; 175(6): 1831-7, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8449889

ABSTRACT

The degradation of 2,4-dinitrotoluene (DNT) by Pseudomonas sp. strain DNT is initiated by a dioxygenase attack to yield 4-methyl-5-nitrocatechol (MNC) and nitrite. Subsequent oxidation of MNC by a monooxygenase results in the removal of the second molecule of nitrite, and further enzymatic reactions lead to ring fission. Initial studies on the molecular basis of DNT degradation in this strain revealed the presence of three plasmids. Mitomycin-derived mutants deficient in either DNT dioxygenase only or DNT dioxygenase and MNC monooxygenase were isolated. Plasmid profiles of mutant strains suggested that the mutations resulted from deletions in the largest plasmid. Total plasmid DNA partially digested by EcoRI was cloned into a broad-host-range cosmid vector, pCP13. Recombinant clones containing genes encoding DNT dioxygenase, MNC monooxygenase, and 2,4,5-trihydroxytoluene oxygenase were characterized by identification of reaction products and the ability to complement mutants. Subcloning analysis suggests that the DNT dioxygenase is a multicomponent enzyme system and that the genes for the DNT pathway are organized in at least three different operons.


Subject(s)
Dinitrobenzenes/metabolism , Genes, Bacterial , Oxygenases/genetics , Pseudomonas/genetics , Cloning, Molecular , Cosmids , Mutation , Oxygenases/metabolism , Phenotype , Plasmids , Pseudomonas/metabolism , Restriction Mapping
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