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Non-alcoholic fatty liver disease (NAFLD) is a common yet little recognized health problem in women with polycystic ovary syndrome (PCOS). In a retrospective setting, we investigated the effects of metformin treatment on the hepatic steatosis index (HSI) as a readily available biomarker panel for NAFLD. HSI values of >36 are considered to be highly suggestive for NAFLD. In our cohort, HSI values indicating NAFLD were found in 60/81 (74.1%) women at baseline. The mean HSI improved significantly after the metformin treatment from 43.2 ± 1.0 to 41.0 ± 1.1. Subgroup analyses of non-obese (body mass index (BMI) < 30 kg/m2), obese (BMI 30–35 kg/m2) and very obese (BMI > 35 kg/m2) women yielded mean baseline HSI values of 35.5 ± 4.5, 41.2 ± 2.7 and 51.2 ± 4.7, respectively. A significant improvement in the HSI of 1.5 ± 2.1 was observed after metformin treatment in non-obese women but not in the obese subgroups. The data suggest a new aspect of metformin treatment in non-obese PCOS patients, namely, a possible improvement in NAFLD. This study highlighted hepatic steatosis as a common comorbidity in PCOS patients that can severely affect their long-term health, and therefore, deserves more attention in the management of PCOS patients. [ABSTRACT FROM AUTHOR]

Quality of life (QoL) is impaired in patients with chronic hypoparathyroidism (HypoPT). With a recently developed specific patient questionnaire, the 28‐item Hypoparathyroid Patient Questionnaire (HPQ 28), we were able to demonstrate an effect of laboratory parameters on symptoms and complaints identified by scales and items of the HPQ 28. Here, we evaluated the effect of conventional treatment modalities on QoL using this specific questionnaire. In this cross‐sectional study, we included 49 HypoPT (41 female and 8 male) patients. Laboratory values of total serum calcium, magnesium, phosphate, calcium‐phosphate product (CPP), and 24‐hour urine for calcium and phosphate were analyzed. Patients completed the HPQ 28 questionnaire during the corresponding visit. Mean age was 57.3 ± 10.5 years and duration of disease 12.6 ± 9.8 years. Most patients (86%, n = 42) were treated with the active vitamin D analogs calcitriol, alfacalcidol, or dihydrotachysterol (DHT). The use of calcium and magnesium supplements influenced scales on HPQ 28 in a dose‐dependent manner. We detected a dose‐dependent increase on the HPQ 28 scales "depression and anxiety" and "pain and cramps," and the item "numbness and tingling" related to calcitriol. This effect was independent of gender, age, underlying disease, kind of surgery, serum 25‐hydroxyvitamin D3, calcium, or phosphate values. This study presents the first data on specific symptoms of HypoPT patients dependent on different treatment modalities. Our data suggest that in part the reduced QoL in these patients might be caused by conventional treatment. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

The human urea transporter SLC14A1 (HUT11/UT-B) has been suggested as a marker for the adipogenic differentiation of bone cells with a relevance for bone diseases. We investigated the function of SLC14A1 in different cells models from bone environment. SLC14A1 expression and cytokine production was investigated in bone cells obtained from patients with osteoporosis. Gene and protein expression of SLC14A1 was studied during adipogenic or osteogenic differentiation of human mesenchymal progenitor cells (hMSCs) and of the single-cell–derived hMSC line (SCP-1), as well as in osteoclasts and chondrocytes. Localization was determined by histochemical methods and functionality by urea transport experiments. Expression of SLC14A1 mRNA was lower in cells from patients with osteoporosis that produced high levels of cytokines. Accordingly, when adding a combination of cytokines to SCP-1 SLC14A1 mRNA expression decreased. SLC14A1 mRNA expression decreased after both osteogenic and more pronounced adipogenic stimulation of hMSCs and SCP-1 cells. The highest SLC14A1 expression was determined in undifferentiated cells, lowest in chondrocytes and osteoclasts. Downregulation of SLC14A1 by siRNA resulted in an increased expression of interleukin-6 and interleukin-1 beta as well as adipogenic markers. Urea influx through SLC14A1 increased expression of osteogenic markers, adipogenic markers were suppressed. SLC14A1 protein was localized in the cell membrane and the cytoplasm. Summarizing, the SLC14A1 urea transporter affects early differentiation of hMSCs by diminishing osteogenesis or by favoring adipogenesis, depending on its expression level. Therefore, SLC14A1 is not unequivocally an adipogenic marker in bone. Our findings suggest an involvement of SLC14A1 in bone metabolism and inflammatory processes and disease-dependent influences on its expression. [ABSTRACT FROM AUTHOR]

In hypoparathyroidism (HypoPT), patients suffer severely from reduced quality of life. The complexity of HypoPT demands a disease‐specific control instrument to characterize symptom load. We employed a newly developed disease‐specific Hypoparathyroid Patient Questionnaire (the HPQ 40/28) to investigate and quantify HypoPT patients' complaints and contributing factors. In this cross‐sectional, two‐center study, patients with postsurgical HypoPT (n = 49) were matched for gender and age and compared with patients having undergone thyroid surgery without HypoPT (n = 39) and patients with primary hyperparathyroidism (n = 35). The HPQ 40/28 was completed when patients visited the respective center. Clinical background information, blood tests, and current medication were documented by the physician. Serum calcium lay within the reference range in 87% of HypoPT patients, serum phosphate in 95.7%, and calcium–phosphate product (CPP) in 100%. HPQ 40/28 scores for the scales "pain and cramps" (PaC), "neurovegetative symptoms" (NVS), "numbness or tingling," and "heart palpitations" were significantly elevated in comparison with control groups. Correlations between complaints and laboratory parameters could be demonstrated in the HypoPT group, with serum calcium correlating with NVS (r = 0.309, p < 0.05) and serum phosphate with loss of vitality (r = 0.349, p < 0.05). CPP was the main contributor to symptom load with an influence on PaC (r = 0.295, p < 0.05), loss of vitality (r = 0.498, p < 0.001), numbness or tingling (r = 0.328, p < 0.05), and memory problems (r = 0.296, p < 0.05). In conclusion, the newly developed HPQ 40/28 successfully identified and quantified symptoms typical in HypoPT patients. Using the HPQ 40/28, the CPP was identified as the predominant factor in the severity of complaints in HypoPT. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

In hypoparathyroidism (HypoPT), patients suffer severely from reduced quality of life. The complexity of HypoPT demands a disease‐specific control instrument to characterize symptom load. We employed a newly developed disease‐specific Hypoparathyroid Patient Questionnaire (the HPQ 40/28) to investigate and quantify HypoPT patients' complaints and contributing factors. In this cross‐sectional, two‐center study, patients with postsurgical HypoPT (n = 49) were matched for gender and age and compared with patients having undergone thyroid surgery without HypoPT (n = 39) and patients with primary hyperparathyroidism (n = 35). The HPQ 40/28 was completed when patients visited the respective center. Clinical background information, blood tests, and current medication were documented by the physician. Serum calcium lay within the reference range in 87% of HypoPT patients, serum phosphate in 95.7%, and calcium–phosphate product (CPP) in 100%. HPQ 40/28 scores for the scales "pain and cramps" (PaC), "neurovegetative symptoms" (NVS), "numbness or tingling," and "heart palpitations" were significantly elevated in comparison with control groups. Correlations between complaints and laboratory parameters could be demonstrated in the HypoPT group, with serum calcium correlating with NVS (r = 0.309, p < 0.05) and serum phosphate with loss of vitality (r = 0.349, p < 0.05). CPP was the main contributor to symptom load with an influence on PaC (r = 0.295, p < 0.05), loss of vitality (r = 0.498, p < 0.001), numbness or tingling (r = 0.328, p < 0.05), and memory problems (r = 0.296, p < 0.05). In conclusion, the newly developed HPQ 40/28 successfully identified and quantified symptoms typical in HypoPT patients. Using the HPQ 40/28, the CPP was identified as the predominant factor in the severity of complaints in HypoPT. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Hypoparathyroidism patients suffer a variety of complaints often leading to reduced quality of life. Currently, no specific standard instrument exists to measure corresponding disease manifestations. We therefore aimed to develop a disease‐characteristic questionnaire for hypoparathyroid patients. We used an analytical‐empirical approach for questionnaire construction based on retrospective analysis of four well‐established but non‐disease‐specific questionnaires (Symptom Checklist 90, revised [SCL‐90‐R]; Giessen Complaint List [GBB]; Short‐Form‐36 Health Survey [SF‐36]; von Zerssen Symptom List [B‐L Zerssen]) and two additional unpublished or local questionnaires (SHGdQ and GPQ) in a German hypoparathyroidism self‐help group (n = 60). Retrospective data were compared with corresponding general population norms. The new questionnaire was administered prospectively over 1 year to patients with postoperative hypoparathyroidism and two control groups to validate specificity. Exploratory factor analysis (EFA) and reliability testing were applied to identify relevant scales and reduce overlapping items. In the self‐help group, SCL‐90‐R revealed elevated symptom load in four complaint areas (p = 0.003 to p < 0.001). The SF‐36 mental summary score (p < 0.001) and further scales were lowered. In the GBB, four of five scales (p = 0.009 to p < 0.001) were elevated. In the B‐L Zerssen, 6 of 24 items revealed complaint areas. Based on these findings, the new 40‐item "Hypoparathyroid Patient Questionnaire" (HPQ 40) was developed, tested prospectively, and further analyzed. EFA revealed five scales (pain and cramps, gastrointestinal symptoms, depression and anxiety, neurovegetative symptoms, loss of vitality), all with Cronbach's alpha >0.7. The questionnaire was revised accordingly and shortened to 28 questions to avoid redundancy. We present a new disease‐characteristic questionnaire for hypoparathyroidism patients. Prospective testing revealed five major complaint areas and promising psychometric properties. This questionnaire can be tested for usefulness in further clinical trials. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Background. Crohn's disease (CD) is associated with a higher prevalence of osteoporosis. The pathogenesis of bone affliction remains controversial, especially if inflammatory cytokines or glucocorticoid therapy are the main contributors. In postmenopausal osteoporosis, bone resorption is induced by IL-6, IL-1ß and TNF-a. In contrast, in children with CD, IL-6 exclusively decreased bone formation without affecting bone resorption. Objectives. The objective of this study was to further clarify the pathophysiology of bone affliction in adult patients with CD with the use of an osteoblast and osteoclast cell model. Material and methods. Inflammatory cytokines IL-6, IL-1ß, and TNF-a were measured in adult CD patients' serum. Mean values of these cytokines were applied with or without dexamethasone to the human cell line SCP-1 (osteoblastic cell model). Also, the effect of cytokines on primary human osteoclast differentiation and activity was determined. Results. The combined cytokine application increased the receptor activator of NF-κB ligand/osteoprotegerin (RANKL/OPG) ratio 2-fold after 2 and 14 days. Additional application of dexamethasone to SCP-1 cells further increased the RANKL/OPG ratio 3-fold, but decreased IL-6 and IL-1ß expression to 10% and 50%, respectively. TNF-a expression was maximally suppressed to 16% by dexamethasone in the presence of cytokines. In osteoclasts, the combined cytokine treatment decreased expression of characteristic genes to approx. 30%, while increasing osteoclast resorption activity to 148%. In addition, a cytokine stimulated osteoblast cell culture-generated supernatant stimulated osteoclast resorption activity by 170%. Conclusions. Our results suggest that IL-6, IL-1ß, and TNF-a only in combination induced osteoclaststimulating activity represented by the RANKL/OPG ratio in osteoblasts. Dexamethasone further increased this effect in osteoblasts, while decreasing cytokine expression. The results in osteoclasts support a direct and osteoblast-mediated effect on bone resorption. Our in vitro results differentiate for the first time the effect of cytokines on bone turnover as measured in adult CD patients from the additional dexamethasone effect on osteoblasts as part of the pathophysiology of osteoporosis. [ABSTRACT FROM AUTHOR]

Even though ipilimumab is a promising antibody used for stage IV melanoma therapy, the response varies and is difficult to predict. We here report on a case of successful treatment with ipilimumab in dacarbazine-resistant metastatic malignant melanoma, including a review of the literature on the long-term treatment results. A 62-year-old patient with a history of a resected lentigo-maligna melanoma 5 years earlier and parotideal metastasis 1 year before was admitted with a newly detected 3.5 cm liver metastasis. Atypical liver resection was performed (R1). Immunohistochemically, CD3+ T-lymphocytes and CD68+ macrophages were detected at the tumour margins and within the parotideal and hepatic melanoma metastases. A sub-analysis of the liver metastasis showed scattered FOX-P3+ regulatory T-lymphocytes as well as multiple CD8+ effector T-cells. Chemotherapy with dacarbazine 1,000 mg/m/day was administered at 4-weeks intervals for 3 months. A follow-up positron-emission computed tomography and liver biopsy revealed melanoma metastases in the liver, lungs, and mediastinum. Compassionate use of ipilimumab was administered at 3 mg/kg every 3 weeks for a total of four doses. After an initial increase in tumour size, most lesions responded, but progressive axillary and cervical lymphadenopathy was observed before complete remission was achieved. Side effects included fatigue, dyspnoea, cough, upper abdominal pain with diarrhoea, and gingival hyperplasia. Now, 36 months after ipilimumab therapy and 8 years after the initial melanoma diagnosis, the tumour did not recur. It would be challenging to hypothesize that long intervals between diagnosis and need for treatment, clinical side effects, an initial increase in tumour size and the presence of intra-tumoural T-cells and macrophages might predict tumour response. [ABSTRACT FROM AUTHOR]

The liver is considered a radiosensitive organ. However, in rats, high single-dose irradiation (HDI) showed only mild effects. Consequences of fractionated irradiation (FI) in such an animal model have not been studied so far. Rats were exposed to selective liver FI (total dose 60 Gy, 2 Gy/day) or HDI (25 Gy) and were killed three months after the end of irradiation. To study acute effects, HDI-treated rats were additionally killed at several time points between 1 and 48 h. Three months after irradiation, no differences between FI and HDI treatment were found for macroscopically detectable small 'scars' on the liver surface and for an increased number of neutrophil granulocytes distributed in the portal fields and through the liver parenchyma. As well, no changes in HE-stained tissues or clear signs of fibrosis were found around the portal vessels. Differences were seen for the number of bile ducts being increased in FI- but not in HDI-treated livers. Serum levels indicative of liver damage were determined for alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase ( γGT) and lactate dehydrogenase (LDH). A significant increase of AP was detected only after FI while HDI led to the significant increases of AST and LDH serum levels. By performing RT-PCR, we detected up-regulation of matrix metalloproteinases, MMP-2, MMP-9, MMP-14, and of their inhibitors, TIMP-1, TIMP-2 and TIMP-3, shortly after HDI, but not at 3 month after FI or HDI. Overall, we saw punctual differences after FI and HDI, and a diffuse formation of small scars at the liver surface. Lack of 'provisional clot'-formation and absence of recruitment of mononuclear phagocytes could be one explanation for scar formation as incomplete repair response to irradiation. [ABSTRACT FROM AUTHOR]

It has been recently shown that the biological effects of erythropoietin (EPO) are not limited to the hematopoietic compartment but, as pleiotropic glycoprotein, this hormone can exert pro-angiogenic and tissue-protective functions also in a wide range of non-hematopoietic organs. The role of EPO and the effective functionality of its receptor in solid tumors are still a controversial point of debate. In the present work we analyzed the gene expression of EPO and its cognate receptor (EpoR) in a rat model of thioacetamide-induced damage and tumor. An analysis of the EPO/EpoR axis was also performed on human cholangiocarcinoma (CC) cell lines. A progressive increase of EPO and EpoR mRNA can already be observed during the fibrotic-cirrhotic development with a peak of expression rising at tumor formation (24.7 ± 9.9-fold increase and 15.5 ± 1.1-fold increase, respectively, for the two genes). Co-localization studies by immunofluorescence revealed hepatocytes in the regenerative cirrhotic nodules (Hep Par-1) and in the dysplastic bile duct cells (CK19) as the major EPO producers in this specific condition. The same cell populations, together with endothelial cells, exhibited an increased expression of EpoR, although all the non-parenchymal cell populations in the liver exhibited modest basal mRNA levels. Challenging human CC cells, Mz-Cha-2, with a combination of EPO and SCF resulted in a synergistic effect on the gene expression of EPO, CyclinD1 and PCNA. This study suggests that the autocrine and paracrine release of endogenous EPO in the microenvironment may contribute to the development and maintenance of the CC possibly in cooperation with other signaling pathways. [ABSTRACT FROM AUTHOR]

It has been suggested that cyclooxygenase-2 (COX-2)-mediated prostaglandin synthesis is associated with liver inflammation and carcinogenesis. The aim of this study is to identify the cellular source of COX-2 expression in different stages, from acute liver injury through liver fibrosis to cholangiocarcinoma (CC). We induced in rats acute and 'chronic' liver injury (thioacetamide (TAA) or carbon tetrachloride (CCl)) and CC development (TAA) and assessed COX-2 gene expression in normal and damaged liver tissue by RT-PCR of total RNA. The cellular localization of COX-2 protein in liver tissue was analyzed by immunohistochemistry as well as in isolated rat liver cells by Western blotting. The findings were compared with those obtained in human cirrhotic liver tissue. The specificity of the antibodies was tested by 2-DE Western blot and mass spectrometric identification of the positive protein spots. RT-PCR analysis of total RNA revealed an increase of hepatic COX-2 gene expression in acutely as well as 'chronically' damaged liver. COX-2-protein was detected in those ED1/ED2 cells located in the non-damaged tissue (resident tissue macrophages). In addition COX-2 positivity in inflammatory mononuclear phagocytes (ED1/ED2), which were also present within the tumoral tissue was detected. COX-2 protein was clearly detectable in isolated Kupffer cells as well as (at lower level) in isolated 'inflammatory' macrophages. Similar results were obtained in human cirrhotic liver. COX-2 protein is constitutively detectable in liver tissue macrophages. Inflammatory mononuclear phagocytes contribute to the increase of COX-2 gene expression in acute and chronic liver damage induced by different toxins and in the CC microenvironment. [ABSTRACT FROM AUTHOR]

Background and Aims: The standard treatment regimen for chronic HCV genotype 3 (HCV-G3) hepatitis consists of PEGylated interferon-α (IFN-α) and ribavirin at varying doses ranging from 400 to 1,200 mg and results in response rates of 80%. However, this therapy has substantial side-effects including anemia, is teratogenic, and costly. To reduce the side-effects of therapy, the role of monotherapy consisting of only IFN-α was investigated.Methods: A retrospective analysis of individual therapy courses of HCV-G3-infected patients who were treated with IFN-α(2a) monotherapy or a combination therapy with attention to the treatment outcome and the presence of IL28B rs12979860 and IL28B rs8099917 single-nucleotide polymorphism genotypes was performed. Conventional prognostic features in each case were assessed as well.Results: In the study, 15/30 (50%) of patients treated with IFN-α(2a) monotherapy and 32/36 (89%) treated with combination therapy achieved a sustained virological response (SVR). In addition, 7/11 (64%) of those treated initially with monotherapy and subsequently with combination therapy achieved an SVR. An "ultra-rapid" virological response occurring within 2 weeks of initiation of therapy (p = 0.005), young age (<40; p < 0.001) and low initial γ-GT/ALT-ratio (p = 0.03) were associated with a SVR to IFN-α(2a) monotherapy. An SVR in those treated with combination therapy was found to be associated with a rapid virological response (RVR) (p = 0.03). The absence of histologic steatosis was associated with SVR in all patient groups (p = 0.01). Therapy duration (24 vs. 48 weeks) did not affect the SVR in either group. As expected, combination therapy resulted in more hematological side-effects than did monotherapy.Conclusions: An "ultra-rapid" virological response, young age, low initial γ-GT/ALT-ratio and absence of steatosis were each associated with an SVR in those receiving IFN-α(2a) monotherapy. Therefore, monotherapy in these patients should still be discussed independently of the existence of the IL28B polymorphisms. [ABSTRACT FROM AUTHOR]

The 'acute phase' is clinically characterized by homeostatic alterations such as somnolence, adinamia, fever, muscular weakness, and leukocytosis. Dramatic changes in iron metabolism are observed under acute-phase conditions. Rats were administered turpentine oil (TO) intramuscularly to induce a sterile abscess and killed at various time points. Tissue iron content in the liver and brain increased progressively after TO administration. Immunohistology revealed an abundant expression of transferrin receptor-1 (TfR1) in the membrane and cytoplasm of the liver cells, in contrast to almost only nuclear expression of TfR1 in brain tissue. The expression of TfR1 increased at the protein and RNA levels in both organs. Gene expression of hepcidin, ferritin-H, iron-regulatory protein-1, and heme oxygenase-1 was also upregulated, whereas that of hemojuvelin, ferroportin-1, and the hemochromatosis gene was significantly downregulated at the same time points in both the brain and the liver at the RNA level. However, in contrast to observations in the liver, gene expression of the main acute-phase cytokine (interleukin-6) in the brain was significantly upregulated. In vitro experiments revealed TfR1 membranous protein expression in the liver cells, whereas nuclear and cytoplasmic TfR1 protein was detectable in brain cells. During the non-bacterial acute phase, iron content in the liver and brain increased together with the expression of TfR1. The iron metabolism proteins were regulated in a way similar to that observed in the liver, possibly by locally produced acute-phase cytokines. The significance of the presence of TfR1 in the nucleus of the brain cells has to be clarified. [ABSTRACT FROM AUTHOR]

Urocortin-1 (UCN) a corticotropin releasing-factor (CRF) related peptide, has been found to be expressed in many different tissues like the central nervous system, the cardiovascular system, adipose tissue, and skeletal muscle. The effects of UCN are mediated via stimulation of CRF-receptors 1 and 2 (CRFR1 and 2, CRFR’s) with a high affinity for CRFR2. It has been shown that the CRF-related peptides and CRFR’s are involved in the regulation of stress-related endocrine, autonomic and behavioural responses. Using immunocytochemistry, immunohistochemistry and RT–PCR, we now can show the differentiation dependent expression of UCN mRNA and peptide in human mesenchymal progenitor cells (MSCs) directed to the osteoblastic phenotype for the first time. UCN expression was down regulated by TGF-beta and BMP-2 in the early proliferation phase of osteoblast development, whereas dexamethasone (dex) minimally induced UCN gene expression during matrix maturation after 24 h stimulation. Stimulation of MSCs for 28 days with ascorbate/beta-glycerophosphate (asc/bGp) induced UCN gene expression at day 14. This effect was prevented when using 1,25-vitamin D3 or dex in addition. There was no obvious correlation to osteocalcin (OCN) gene expression in these experiments. In MSCs from patients with metabolic bone disease ( n = 9) UCN gene expression was significantly higher compared to MSCs from normal controls ( n = 6). Human MSCs did not express any of the CRFR’s during differentiation to osteoblasts. Our results indicate that UCN is produced during the development of MSCs to osteoblasts and differentially regulated during culture as well as by differentiation factors. The expression is maximal between proliferation and matrix maturation phase. However, UCN does not seem to act on the osteoblast itself as shown by the missing CRFR’s. Our results suggest new perspectives on the role of urocortin in human skeletal tissue in health and disease. [ABSTRACT FROM AUTHOR]

Eighteen different aerobic bacteria were isolated which utilized quinoline as sole source of carbon, nitrogen, and energy. Attempts were unsuccessful at isolating anaerobic quinoline-degrading bacteria. The optimal concentration of quinoline for growth was in the range of 2.5 to 5 mM. Some organisms excreted 2-hydroxyquinoline as the first intermediate. Hydroxylation of quinoline was catalyzed by a dehydrogenase which was induced in the presence of quinoline or 2-hydroxyquinoline. Quinoline dehydrogenase activity was dependent on the availability of molybdate in the growth medium. Growth on quinoline was inhibited by tungstate, an antagonist of molybdate. Partially purified quinoline dehydrogenase from Pseudomonas putida Chin IK indicated the presence of flavin, iron-sulfur centers, and molybdenum-binding pterin. M of quinoline dehydrogenase was about 300 kDa in all isolates investigated. [ABSTRACT FROM AUTHOR]