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1.
Clin Oncol (R Coll Radiol) ; 29(8): 528-537, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28595873

ABSTRACT

Borderline sarcomas and smooth muscle tumours of uncertain malignant potential (STUMP) have an unpredictable clinical behaviour with frequent local recurrences and rarely, metastases. We review the current management of common subtypes of borderline sarcomas and STUMP.


Subject(s)
Sarcoma , Smooth Muscle Tumor , Humans
2.
Clin Oncol (R Coll Radiol) ; 29(8): 467-470, 2017 08.
Article in English | MEDLINE | ID: mdl-28583345
3.
Clin Oncol (R Coll Radiol) ; 29(8): 507-515, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28552518

ABSTRACT

Systematic treatment of adult-type soft tissue sarcoma is evolving. Its role in the neoadjuvant setting is currently experimental, whereas the data on adjuvant chemotherapy are inconclusive. Nevertheless, in clinical practice, neoadjuvant and adjuvant chemotherapy may be considered on an individual basis after multidisciplinary discussion. Systemic therapy has a well-established role in the management of locally advanced and metastatic disease and histology-based treatment approaches are being studied.


Subject(s)
Chemotherapy, Adjuvant/methods , Sarcoma/drug therapy , Sarcoma/therapy , Humans , Sarcoma/pathology
4.
Ann Oncol ; 23(7): 1845-53, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22104575

ABSTRACT

BACKGROUND: The aim was to evaluate the accuracy of Cockcroft-Gault, Jelliffe, Wright and Modification of Diet in Renal Disease (MDRD) formulae as a substitute for the gold standard measure of glomerular filtration rate (GFR) using chromium 51 EDTA. PATIENTS AND METHODS: Retrospective analysis of GFR measurements in oncology patients from a University Teaching Hospital over 3 years was carried out. Bias and precision of estimates of GFR were compared with measured GFR. RESULTS: Six hundred and sixty patients with measured GFR (median 90 ml/min, range 23-179 ml/min) were identified. Cockcroft-Gault produced the smallest bias (median percentage error -1.4%) and highest precision (median absolute percentage error 14.0%) and was the most accurate for carboplatin dosing. For patients>30% over their ideal body weight (IBW), using IBW+30% in the Cockcroft-Gault formula was more precise than using actual body weight or IBW. The Wright formula was most accurate for patients aged 70+years and patients with a body mass index (BMI)≥30 but overestimated GFR when GFR<50 ml/min. CONCLUSIONS: When measured GFR is unavailable, we advise estimating GFR using the Cockcroft-Gault formula and using IBW+30% for patients weighing>30% over their IBW. If the GFR is ≥50 ml/min and the patient is >70 years and/or BMI≥30, the Wright formula gives the best estimate of GFR.


Subject(s)
Drug Dosage Calculations , Glomerular Filtration Rate , Kidney Function Tests , Adolescent , Adult , Aged , Aged, 80 and over , Algorithms , Area Under Curve , Body Mass Index , Carboplatin/pharmacology , Carboplatin/therapeutic use , Female , Humans , Male , Middle Aged , Neoplasms/drug therapy , Neoplasms/physiopathology , Retrospective Studies , Young Adult
5.
Gynecol Oncol ; 121(3): 625-36, 2011 Jun 01.
Article in English | MEDLINE | ID: mdl-21353692

ABSTRACT

OBJECTIVES: Malignant ovarian germ cell tumours (MOGCT) are rare cancers of young women. Limited prospective trials exist from which evidence-based management can be developed. This review summarizes the available literature concerning MOGT in order to provide the clinician with information relevant to their multidisciplinary management. METHODS: MEDLINE was searched between 1966 and 2010 for all publications in English where the studied population included women diagnosed with malignant ovarian germ cell tumours. RESULTS: The majority of patients can be cured with fertility-preserving surgery with or without combination chemotherapy. Long term survival approaches 100% in early stage disease and is approximately 75% in advanced stage disease. Most studies suggest that the treatment has little, if any, effect on future fertility and limited data suggest that there is no adverse effect on the future quality of life. CONCLUSION: MOGCTs are rare tumours of young women the majority of which can be successfully treated with fertility-preserving surgery with or without chemotherapy with preservation of reproductive function. Minimisation of chemotherapy in good prognostic groups and improved treatment in resistant and relapsed MOGCT are important goals for the future. Further studies are needed to quantify the late adverse effects of treatment in long term survivors.


Subject(s)
Neoplasms, Germ Cell and Embryonal/drug therapy , Neoplasms, Germ Cell and Embryonal/surgery , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/surgery , Combined Modality Therapy , Female , Fertility , Humans , Treatment Outcome
6.
Cell Mol Life Sci ; 65(11): 1631-52, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18324353

ABSTRACT

Curcumin is the active ingredient in the traditional herbal remedy and dietary spice turmeric (Curcuma longa). Curcumin has a surprisingly wide range of beneficial properties, including anti-inflammatory, antioxidant, chemopreventive and chemotherapeutic activity. The pleiotropic activities of curcumin derive from its complex chemistry as well as its ability to influence multiple signaling pathways, including survival pathways such as those regulated by NF-kappaB, Akt, and growth factors; cytoprotective pathways dependent on Nrf2; and metastatic and angiogenic pathways. Curcumin is a free radical scavenger and hydrogen donor, and exhibits both pro- and antioxidant activity. It also binds metals, particularly iron and copper, and can function as an iron chelator. Curcumin is remarkably non-toxic and exhibits limited bioavailability. Curcumin exhibits great promise as a therapeutic agent, and is currently in human clinical trials for a variety of conditions, including multiple myeloma, pancreatic cancer, myelodysplastic syndromes, colon cancer, psoriasis and Alzheimer's disease.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal , Antineoplastic Agents , Antioxidants , Curcumin , Free Radical Scavengers , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/metabolism , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Antineoplastic Agents/chemistry , Antineoplastic Agents/metabolism , Antineoplastic Agents/therapeutic use , Antioxidants/chemistry , Antioxidants/metabolism , Antioxidants/therapeutic use , Clinical Trials as Topic , Curcuma/chemistry , Curcumin/chemistry , Curcumin/metabolism , Curcumin/therapeutic use , Free Radical Scavengers/chemistry , Free Radical Scavengers/metabolism , Free Radical Scavengers/therapeutic use , Humans , Iron/metabolism , NF-kappa B/antagonists & inhibitors , Neoplasms/drug therapy , Neoplasms/pathology , Oxidation-Reduction , Signal Transduction/physiology
7.
Am Fam Physician ; 74(4): 613-8, 2006 Aug 15.
Article in English | MEDLINE | ID: mdl-16939183

ABSTRACT

Digoxin therapy has long been used to treat heart failure; however, its effectiveness was not completely known until recently. Results of the Digitalis Investigation Group trial showed that adding digoxin to standard heart failure therapy had no effect on mortality. However, adding digoxin decreased hospitalizations related to heart failure and improved symptoms in patients treated for heart failure. Reanalyses of the trial's findings have raised new questions about the role of digoxin in heart failure treatment. These new analyses showed that low serum digoxin concentrations used in patients with more severe disease offered the most benefit. Digoxin use in women was associated with increased mortality risk. This finding should be interpreted with caution, however, because it was based on retrospective data, and the cause of this phenomenon has not been fully elucidated. Prospective clinical trials are needed to determine the serum digoxin concentration that is associated with the most clinical benefit and to determine the role of digoxin therapy for women. Digoxin generally does not have a role in the treatment of diastolic heart failure and is not a first-line therapy for managing atrial fibrillation in patients with heart failure.


Subject(s)
Cardiotonic Agents/therapeutic use , Digoxin/therapeutic use , Heart Failure/drug therapy , Algorithms , Atrial Fibrillation/complications , Digoxin/blood , Female , Heart Failure/complications , Humans , Male , Sex Factors , Treatment Outcome
8.
Int J Surg ; 3(3): 206-12, 2005.
Article in English | MEDLINE | ID: mdl-17462285

ABSTRACT

Gastrointestinal stromal tumours (GISTs) are defined as a group of C-KIT positive mesenchymal tumours of the gastrointestinal tract. Although they may arise throughout the gut, the commonest sites are stomach and small intestine. Over 80% of metastases are to the liver and omentum. Targeted therapy (imatinib) can inhibit C-KIT and thereby aberrant tumoural proliferation. Imatinib may induce shrinkage of lesions and cystic change. Such physical changes often correspond with reduced metabolic activity demonstrated by (18-FDG)PET scans. These changes may enable metastatectomy reducing tumour pain and the risk of haemorrhage and rupture in the short term. In the long term, resection may lessen the risk of recurrence by removing potentially resistant clones. The precise role of palliative resection for GIST metastases on imatinib remains unclear. Imatinib has changed the natural history of metastatic GISTs, with increased survival times. Surgery remains an important management strategy in the metastatic setting because complete pathological responses are rare with imatinib. Surgery is likely to provide the best palliation, greatest reduction in tumour burden and eliminate resistant clones. A multidisciplinary team approach with expertise concentrated in a few centres specialising in the management of these rare tumours is vital to the successful outcome. Future issues regarding the management of differential response of the metastases to imatinib are highlighted. With the emergence of techniques enabling identification of the precise mutational status of the C-KIT oncogene, the imatinib/surgery sequence could be tailored to the type of C-KIT mutation.

9.
Am J Physiol Endocrinol Metab ; 279(2): E356-65, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10913036

ABSTRACT

Obesity-resistant (A/J) and obesity-prone (C57BL/6J) mice were weaned onto low-fat (LF) or high-fat (HF) diets and studied after 2, 10, and 16 wk. Despite consuming the same amount of food, A/J mice on the HF diet deposited less carcass lipid and gained less weight than C57BL/6J mice over the course of the study. Leptin mRNA was increased in white adipose tissue (WAT) in both strains on the HF diet but to significantly higher levels in A/J compared with C57BL/6J mice. Uncoupling protein 1 (UCP1) and UCP2 mRNA were induced by the HF diet in brown adipose tissue (BAT) and WAT of A/J mice, respectively, but not in C57BL/6J mice. UCP1 mRNA was also significantly higher in retroperitoneal WAT of A/J compared with C57BL/6J mice. The ability of A/J mice to resist diet-induced obesity is associated with a strain-specific increase in leptin, UCP1, and UCP2 expression in adipose tissue. The findings indicate that the HF diet does not compromise leptin-dependent regulation of adipocyte gene expression in A/J mice and suggest that maintenance of leptin responsiveness confers resistance to diet-induced obesity.


Subject(s)
Dietary Fats , Leptin/biosynthesis , Membrane Transport Proteins , Mitochondrial Proteins , Obesity/metabolism , Adipose Tissue/metabolism , Adipose Tissue, Brown/metabolism , Animals , Body Weight/physiology , Carrier Proteins/genetics , Carrier Proteins/metabolism , Eating/physiology , Energy Intake/physiology , Gene Expression , Growth/physiology , Ion Channels , Leptin/genetics , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Mice, Inbred A , Mice, Inbred C57BL , Obesity/genetics , Proteins/genetics , Proteins/metabolism , RNA, Messenger/metabolism , Species Specificity , Uncoupling Protein 1 , Uncoupling Protein 2 , Uncoupling Protein 3
10.
FASEB J ; 13(13): 1839-44, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10506588

ABSTRACT

Rat kallikrein-binding protein (KBP), a member of the serpin family, is a tissue kallikrein inhibitor. It has been shown to be a potential pathogenic factor of diabetic retinopathy and may play a role in animal development and growth. To determine whether reduced KBP expression is involved in retarded animal growth, we examined the in vivo effect of growth hormone (GH) deficiency on the expression of KBP in the Lewis dwarf (dw/dw). We found that serum levels of functionally active KBP were reduced in the dwarf rat (P < 0.05) as determined by complex formation assay between serum KBP and (125)I-labeled rat tissue kallikrein. Enzyme-linked immunosorbent assay showed that KBP levels were significantly reduced in the serum of the dwarf rat compared to the Lewis rat (213.8 ng/ml vs. 413.8 ng/ml, n = 4, P < 0.01). The decreased KBP levels were confirmed by Western blot analysis. Moreover, treatment of the dwarf rat with recombinant human GH for 4 wk resulted in a significant increase in KBP activity (P < 0.01) and serum KBP levels compared with the untreated dwarf rat (549.8 ng/ml, n = 5, vs. 213.8 ng/ml, n = 4, P < 0.02). Northern blot analysis and densitometry showed that liver KBP mRNA levels were reduced by fivefold in the dwarf rat compared to the Lewis rat and the decrease was reversed by the GH treatment. These results indicate that the KBP levels are regulated at the RNA level. Furthermore, in vitro studies using cultured rat hepatocytes showed that GH may have a direct regulatory effect on KBP expression since KBP levels increased in the conditioned media of cells treated with GH. These results demonstrated that KBP is reduced in the genetic dwarf rat and is restored to normal by GH; therefore, KBP is a GH-dependent protein and may be a new target for studying the mechanism of pathological animal growth.


Subject(s)
Carrier Proteins/metabolism , Human Growth Hormone/pharmacology , Serpins/metabolism , Tissue Kallikreins/metabolism , Animals , Carrier Proteins/genetics , Human Growth Hormone/genetics , Liver/chemistry , Protein Binding , RNA, Messenger/analysis , Rats , Rats, Inbred Lew , Rats, Mutant Strains , Recombinant Proteins/pharmacology , Serpins/genetics , Tissue Kallikreins/antagonists & inhibitors
11.
Invest Ophthalmol Vis Sci ; 38(3): 658-64, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9071220

ABSTRACT

PURPOSE: To determine the involvement of rat kallikrein-binding protein (RKBP) in the development of diabetic retinopathy. METHODS: Diabetes was induced by streptozotocin (STZ) (55 mg/kg body weight in 0.05 M citrate buffer, pH 4.5) in male Sprague-Dawley rats (150 to 175 g, 6 weeks old) as confirmed by hyperglycemia and reduced body weight. Retinas were dissected from animals at 1, 2, and 4 months of diabetes. The functional activity of RKBP in retinal homogenates was determined by its complex formation with tissue kallikrein. Immunoreactive RKBP levels were measured by enzyme-linked immunosorbent assay. The RKBP messenger RNA (mRNA) levels in the retina were measured by Northern blot analysis using the RKBP complementary DNA probe. The activity of total Na+,K(+)-ATPase was determined by a radioassay. Total protein concentration was determined by a protein assay. RESULTS: The kallikrein-binding activity was reduced in the retinas of STZ-diabetic rats at 1 (59%), 2 (50%), and 4 (38%) months of diabetes compared to those of age-matched control subjects. Levels of immunoreactive RKBP were significantly lower in the diabetic animals at each time point examined compared to those of control subjects. At 1 and 2 months of diabetes, RKBP levels (nanogram/milligram protein) were decreased significantly to 6.9 +/- 0.7 (n = 8) and 10.6 +/- 1.0 (n = 8), respectively, compared to those of age-matched control subjects (14.1 +/- 0.7, n = 8, P < 0.001, and 14.1 +/- 1.2, n = 8, P < 0.01). At 4 months of diabetes, retinal RKBP levels were lower in both control and diabetic groups, but RKBP levels in diabetic groups were significantly lower (5.8 +/- 0.6, n = 8) than those of the age-matched control subjects (8.4 +/- 0.9, n = 8, P < 0.01). Similarly, Northern blot analysis showed that RKBP mRNA levels were reduced in the retina of each group of STZ-diabetic rats, suggesting that the decrease in RKBP occurred at the level of transcription. CONCLUSIONS: The results show that STZ-induced diabetic rats have decreased retinal RKBP; moreover, this suggests that RKBP may contribute to diabetic retinopathy.


Subject(s)
Carrier Proteins/metabolism , Diabetes Mellitus, Experimental/metabolism , Diabetic Retinopathy/metabolism , Kallikreins/metabolism , Retina/metabolism , Serpins/metabolism , Animals , Blotting, Northern , Carrier Proteins/genetics , Enzyme-Linked Immunosorbent Assay , Kallikreins/genetics , Male , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Serpins/genetics , Sodium-Potassium-Exchanging ATPase/metabolism , Streptozocin
12.
Exp Eye Res ; 63(1): 19-26, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8983960

ABSTRACT

Tissue kallikrein is a serine proteinase which processes kininogens to release bioactive kinins. Kinins mediate a variety of biological processes through the interaction with kinin receptors. Kinins are involved in the regulation of blood pressure and local blood flow, vasodilation, smooth muscle contraction and relaxation, production of pain and inflammation, and stimulation of cell proliferation. The tissue kallikrein-kinin system has been implicated in a number of pathophysiological processes such as hypertension, allergy and diabetes mellitus. In the present study, we have identified the expression and localization of components of the kallikrein-kinin system in the human eye by reverse transcription-polymerase chain reaction (RT-PCR) and Southern blot analyses, and in situ hybridization histochemistry. RT-PCR and Southern blot analyses have detected mRNAs of the key components of the system including tissue kallikrein, low molecular weight kininogen, and bradykinin B1 and B2 receptors at high levels in human retina, choroid and ciliary body, and relatively low levels in the optic nerve. In situ hybridization has identified cellular localization of these four mRNAs in ocular tissues. They are expressed in retinal neuronal cells including the outer nuclear layer, inner nuclear layer and ganglion cell layer. These mRNAs were also identified in endothelial cells of ocular blood vessels, ciliary muscle and lens epithelial cells. The sense riboprobes showed negative staining, which indicates the specificity of the antisense riboprobes. These results suggest that the tissue kallikrein-kinin system is produced endogenously in human ocular tissues. Similar expression patterns of kallikrein, kininogen and kinin receptors indicate that the kallikrein-kinin system may function in an autocrine or paracrine fashion in the eye.


Subject(s)
Kallikrein-Kinin System , Ocular Physiological Phenomena , Base Sequence , Blotting, Southern , Choroid/chemistry , Choroid/physiology , Ciliary Body/chemistry , Ciliary Body/physiology , DNA Primers/genetics , Eye/chemistry , Humans , In Situ Hybridization , Kallikreins/analysis , Kallikreins/genetics , Kininogens/analysis , Kininogens/genetics , Molecular Sequence Data , Optic Nerve/chemistry , Optic Nerve/physiology , Polymerase Chain Reaction , RNA, Messenger/analysis , Receptor, Bradykinin B1 , Receptor, Bradykinin B2 , Receptors, Bradykinin/analysis , Receptors, Bradykinin/genetics , Retina/chemistry , Retina/physiology
13.
N Engl J Med ; 332(24): 1594-9, 1995 Jun 15.
Article in English | MEDLINE | ID: mdl-7753137

ABSTRACT

BACKGROUND: Congenital osteopetrosis is a rare osteosclerotic bone disease characterized by both a defect in osteoclastic function and reduced generation of superoxide by leukocytes. The disease is frequently fatal during the first decade of life. A six-month trial of therapy with recombinant human interferon gamma-1b in eight patients with osteopetrosis provided evidence of benefit, prompting this study of more prolonged therapy. METHODS: We studied 14 patients with severe osteopetrosis treated with subcutaneous injections of recombinant human interferon gamma-1b (1.5 micrograms per kilogram of body weight per dose) three times per week for at least 6 months; 11 patients were treated for 18 months. We assessed the effect of therapy by evaluating the patients' clinical status, measuring blood counts and biochemical markers of bone turnover, and performing bone marrow imaging and bone biopsies. RESULTS: After 6 months of therapy, all 14 patients had decreases in trabecular-bone area (determined by histomorphometric analysis of bone-biopsy specimens) and increases in bone marrow space (determined by marrow imaging), and the improvement was sustained in the 11 patients treated for 18 months. The mean (+SD) hemoglobin concentration increased from 7.5 +/- 2.9 to 10.5 +/- 0.3 g per deciliter (P = 0.05), and superoxide generation by granulocyte-macrophage colonies increased (P < 0.001) after 18 months of therapy. In six patients for whom pretreatment data were available, there was a 96 percent decrease in the frequency of infections requiring antibiotic therapy during interferon treatment. There were no side effects necessitating the discontinuation of therapy. CONCLUSIONS: Long-term therapy with interferon gamma in patients with osteopetrosis increases bone resorption and hematopoiesis and improves leukocyte function.


Subject(s)
Interferon-gamma/therapeutic use , Osteopetrosis/congenital , Osteopetrosis/therapy , Adult , Bone Resorption , Child, Preschool , Humans , Injections, Subcutaneous , Interferon-gamma/administration & dosage , Osteopetrosis/pathology , Recombinant Proteins/administration & dosage , Recombinant Proteins/therapeutic use
14.
J Pediatr ; 121(1): 119-24, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1320672

ABSTRACT

A defect in leukocytic superoxide formation has been demonstrated in patients with congenital osteopetrosis. This leukocyte defect appears to be related to defective bone resorption. Because recombinant human interferon gamma therapy enhances superoxide production in patients with chronic granulomatous disease, we sought to determine whether a similar strategy could reverse the osteopetrotic condition. Interferon gamma, 1.5 micrograms/kg three times a week, was administered by subcutaneous injection for 6 months to eight patients with osteopetrosis. Urinary hydroxyproline and urinary calcium excretion increased markedly during therapy in parallel with a significant decrease in trabecular bone volume. Bone marrow scans demonstrated increased bone marrow production. The hemoglobin concentration, platelet count, and leukocyte production of superoxide increased significantly. No serious infections were encountered during the therapy. These data suggest that interferon gamma administration enhances bone resorption and leukocyte function in patients with osteopetrosis.


Subject(s)
Interferon-gamma/therapeutic use , Osteopetrosis/therapy , Bone Marrow/pathology , Bone Resorption/metabolism , Bone and Bones/metabolism , Bone and Bones/pathology , Calcium/urine , Calcium, Dietary/administration & dosage , Child , Child, Preschool , Hearing/physiology , Hemoglobins/analysis , Humans , Hydroxyproline/urine , Infant , Injections, Subcutaneous , Interferon-gamma/administration & dosage , Interferon-gamma/adverse effects , Osteoclasts/pathology , Osteopetrosis/pathology , Osteopetrosis/urine , Platelet Count , Recombinant Proteins , Superoxides/metabolism
15.
Biotechnol Adv ; 2(2): 309-17, 1984.
Article in English | MEDLINE | ID: mdl-14545701

ABSTRACT

Deposit control in the pulp and paper industry has traditionally been accomplished by the use of toxic biocides. A method has been found whereby biological deposits can be controlled by the use of an enzyme-based product. Numerous field studies have been conducted successfully and photographs prepared illustrating the process. The dynamics of deposit formation and problems associated with such formations have been the subject of considerable study. Development and control of deposit problems under different paper mill conditions using the chemical-biochemical approach will be discussed.

16.
Appl Microbiol ; 28(5): 748-52, 1974 Nov.
Article in English | MEDLINE | ID: mdl-4374119

ABSTRACT

The Association of Official Analytical Chemists bacterial use-dilution test for evaluating liquid surface disinfectants was modified to determine the efficacy of three common environmental germicide compounds against representatives of four virus groups. Modifications were made to conform to the Environmental Protection Agency guidelines on virucidal testing procedures. Alterations included: the use of a concentrated tissue culture preparation of virus instead of a standard bacterial culture; HEp-2 tissue culture cells as a visible test system in place of standard nutrient broth; and controls to measure the virus titer end point and the toxicity of the disinfectant to the cell cultures. Comparison of control end points with results from the test proper were the measure of the effectiveness of the germicides against the viruses. Results are described which agree with those based on other methods previously reported.


Subject(s)
Antiviral Agents/standards , Disinfectants/standards , Adenoviridae/drug effects , Carcinoma, Squamous Cell , Cell Line , Drug Evaluation, Preclinical , Humans , Iodine/standards , Laryngeal Neoplasms , Micropore Filters , Phenols/standards , Poliovirus/drug effects , Quaternary Ammonium Compounds/standards , Simplexvirus/drug effects , Vaccinia virus/drug effects
18.
Appl Microbiol ; 21(2): 181-6, 1971 Feb.
Article in English | MEDLINE | ID: mdl-5549699

ABSTRACT

Heterotrophic conversion of l-aspartic acid to nitrification products by Aspergillus flavus was studied in a replacement incubation system. Numerous amino acids supported nitrification; aspartate and glutamate were about equivalent as the best sources of nitrate. Addition of sodium bicarbonate to the incubation system substantially enhanced nitrate formation for all nitrifiable amino acids except aspartic acid, but the basis for the bicarbonate effect is obscure. The yield of nitrate from l-aspartate was not approached by forms of aspartic acid resulting from substitution on the beta carbon, the amino nitrogen, or the gamma carboxyl group or by aspartate presented as the d-configuration. There was no relationship between nitrate formation and the occurrence of such possible intermediates as nitrite, bound hydroxylamine, ammonia, aspergillic acid, and beta-nitropropionic acid. Uniformly labeled (14)C-l-aspartate that was nitrified in replacement incubation led to no accumulation of label in possible nitrification products in the culture filtrate. Label was found in components of the mycelium after acid hydrolysis, with heaviest accumulation in what appeared to be glucosamine and an unidentified compound, possibly acetylglucosamine. Detectable label was redistributed into serine, glycine, and threonine.


Subject(s)
Aspartic Acid/metabolism , Aspergillus/metabolism , Nitrates/biosynthesis , Nitrites/biosynthesis , Amino Acids/metabolism , Ammonia/analysis , Ammonia/biosynthesis , Anti-Bacterial Agents/biosynthesis , Aspergillus/drug effects , Aspergillus/growth & development , Autoradiography , Bacteriological Techniques , Bicarbonates/pharmacology , Carbon Isotopes , Cell Line , Chromatography, Paper , Colorimetry , Culture Media , Filtration , Freeze Drying , Glucosamine/biosynthesis , Glutamates/metabolism , Hydrogen-Ion Concentration , Hydroxylamines/biosynthesis , Pyrazines/biosynthesis , Sodium , Solvents , Stereoisomerism
20.
Univ Mich Med Cent J ; 33(4): 151-2, 1967.
Article in English | MEDLINE | ID: mdl-6060380
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