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Fan JM, Huang XR, Ng YY, Nikolic-Paterson DJ, Mu W, Atkins RC, Lan HY. Interleukin-1 induces tubular epithelial-myofibroblast transdifferentiation through a transforming growth factor-beta1-dependent mechanism in vitro. Am J Kidney Dis 2001; 37:820-31. [PMID: 11273883 DOI: 10.1016/s0272-6386(01)80132-3] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Interleukin-1 (IL-1) has been shown to exert profibrotic activity in a number of disease models, including crescentic glomerulonephritis and pulmonary fibrosis, but the mechanisms by which this operates are poorly understood. Recent studies have identified a novel mechanism promoting renal fibrosis: tubular epithelial-myofibroblast transdifferentiation (TEMT). The present study examined whether IL-1 can stimulate TEMT in vitro. Cells of the normal rat kidney tubular epithelial cell line (NRK52E) were grown to confluence on collagen-coated plates and cultured for 5 days in the presence 1 to 20 ng/mL of IL-1alpha. Doses of 10 to 20 ng/mL of IL-1 caused transdifferentiation of NRK52E cells into myofibroblast-like cells. Scanning electron microscopy identified IL-1-induced morphological changes as a loss of apical-basal polarity and microvilli, cell hypertrophy, and the development of an elongated and invasive appearance. Phenotypically, IL-1-induced TEMT was characterized by de novo messenger RNA and protein expression of the mesenchymal marker alpha-smooth muscle actin, shown by Northern blotting, immunohistochemistry, and Western blotting. This was accompanied by loss of the epithelial marker E-cadherin. The addition of an excess of IL-1-receptor antagonist completely inhibited IL-1-induced TEMT. IL-1 was shown to stimulate the secretion of active transforming growth factor-beta1 (TGF-beta1) by NRK52E cells. Furthermore, the addition of a neutralizing anti-TGF-beta1 antibody inhibited IL-1-induced TEMT. In conclusion, IL-1 is a profibrogenic cytokine capable of inducing TEMT through a TGF-beta1-dependent mechanism. This may represent a novel mechanism by which IL-1 induces renal fibrosis in vivo.
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Lin YP, Wu MH, Ng YY, Lee RC, Liou JK, Yang WC, Wang JH, Teng MM, Huang TP. Spiral computed tomographic angiography--a new technique for evaluation of vascular access in hemodialysis patients. Am J Nephrol 2000; 18:117-22. [PMID: 9569953 DOI: 10.1159/000013319] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Spiral computed tomographic angiography (CTA), a new noninvasive imaging technique, was used to study 10 arteriovenous fistulas (AVF) in 9 hemodialysis patients. Digital subtraction angiography (DSA) was also performed as a gold standard for comparison. AVF stenosis was graded by a four-point scale: grade 0, well patency of supplying artery, anastomosis and drainage vein; grade 1, < 50% stenosis; grade 2, 50-70% stenosis; grade 3, 70-99% stenosis, and grade 4, total occlusion. We found CTA correlated closely to DSA in detecting both stenosis and dilatation of AVF and it spared all the shortcomings of DSA. CTA has the potential to be alternative for imaging of dialysis fistulas. Further studies will be performed to specify the role of CTA images in the assessment of the hemodialysis vascular access.
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Yang AH, Ng YY, Tarng DC, Chen JY, Shiao MS, Kao JT. Association of apolipoprotein E polymorphism with lipoprotein glomerulopathy. Report of 2 cases with a new genotype and comparison of the relative frequencies of apolipoprotein E isoforms in lipoprotein glomerulopathy and in the general population. Nephron Clin Pract 2000; 78:266-70. [PMID: 9546684 DOI: 10.1159/000044933] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Two cases of lipoprotein glomerulopathy with a new apolipoprotein E (Apo E) genotype, epsilon3/epsilon4, were diagnosed recently. These 2 cases, together with other cases documented in English literature made a total of 6 common isoforms of Apo E encountered in lipoprotein glomerulopathy. Although the calculated allele frequency of epsilon2 is relatively high in cases with lipoprotein glomerulopathy as compared with that in the general population (39.3 vs. 6.4-11.4%), the gradual emergence of Apo E isoforms other than E2/E3 in lipoprotein glomerulopathy implicates that the genetic susceptibility of certain Apo E isoforms may not be a crucial factor. An alteration in the local environment of glomerular capillaries may be more important in the pathogenesis of lipoprotein glomerulopathy.
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Vu C, Ng YY. Prevalence of Helicobacter pylori in peptic ulcer disease in a Singapore hospital. Singapore Med J 2000; 41:478-81. [PMID: 11281437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
INTRODUCTION High Helicobacter pylori (H. pylori) prevalence is well documented among peptic ulcer patients. However, there have been recent reports of declining H. pylori infection rates in developed countries. Based on previous local data in a different hospital, H. pylori prevalence was 66% in gastric ulcer, 86% in duodenal ulcer and 75% in combined gastric and duodenal ulcers. Our present study aims to review the recent H. pylori prevalence in peptic ulcer patients in a Singapore hospital. H. pylori infection rate in relation to sex, age, non-steroidal anti-inflammatory drug (NSAID) use and race were also examined. METHODS Over a 6-month period, patients diagnosed with peptic ulcer by oesophagogastroduodenoscopy were selected. Relevant information was obtained from case notes retrieved from the Medical Records Office. H. pylori status was assessed by rapid urease test (CLOtest) and/or histology. Exclusion criteria were(1) history of peptic ulcer(2), active bleeding(3), cancer or(4) recent use of antibiotics or proton pump inhibitors. RESULTS 107 peptic ulcer patients were selected; 53 gastric ulcer, 47 duodenal ulcer and 7 with combined gastric and duodenal ulcers. Overall H. pylori prevalence was 67.9%(36/53), 85.1%(40/47) and 85.7%(6/7) respectively. Except for the gender variable in gastric ulcer group, age, race and NSAID use was not found to influence H. pylori prevalence. CONCLUSIONS The prevalence of H. pylori among our peptic ulcer patients is slightly lower compared to overseas studies but the local trend,when compared indirectly to another previous local study did not appear to have changed much. Reasons for the lower H. pylori infection rate in comparison to overseas studies are discussed. The lower H. pylori prevalence among female gastric ulcer patients may be due to the higher prevalence of NSAID use.
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Hung SC, Wen YK, Ng YY, Yang WC. Inappropriate antidiuresis associated with pituitary adenoma--mechanisms not involving inappropriate secretion of vasopressin. Clin Nephrol 2000; 54:157-60. [PMID: 10968694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
We report an unusual case of inappropriate antidiuresis with undetectable vasopressin in an elderly man presenting with confusion due to severe hyponatremia. Further investigations led to the diagnosis of non-functional pituitary macroadenoma. The patient had normal thyroid and adrenal function. The abnormal water balance resolved promptly after transsphenoidal removal of the tumor, confirmed by a repeat water loading test. We conclude that inappropriate antidiuresis in the absence of excess vasopressin secretion may implicate mass effect from an underlying pituitary tumor.
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Lin HS, Chean CS, Ng YY, Chan SY, Ho PC. 2-hydroxypropyl-beta-cyclodextrin increases aqueous solubility and photostability of all-trans-retinoic acid. J Clin Pharm Ther 2000; 25:265-9. [PMID: 10971776 DOI: 10.1046/j.1365-2710.2000.00285.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND All-trans-retinoic acid (ATRA, vitamin A acid or tretinoin) is effective in the treatment of acute promyelocytic leukaemia (APL). Unfortunately, the oral absorption of ATRA is highly variable. Its poor aqueous solubility also makes it difficult to be formulated into parenteral formulation. To date, there is no parenteral formulation of ATRA available commercially. OBJECTIVE To undertake the preformulation work necessary for developing such a product. METHOD We investigated the solubility and stability profile of ATRA in various formulations. RESULTS The aqueous solubility of ATRA could be greatly increased by the inclusion of ATRA in 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CD). Adjusting the pH value further improved the water solubility of ATRA. The photostability of HP-beta-CD-based formulation of ATRA was evaluated and it was found that inclusion ATRA into HP-beta-CD did improve the photostability of ATRA. CONCLUSION These results showed that it is possible to develop a parenteral formulation and/or an aqueous oral formulation of all-trans-retinoic acid by using 2-hydroxypropyl-beta-cyclodextrin. However, the biopharmaceutical properties of such a formulation would be necessary before its use.
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Lee CC, Ng YY, Chou YH, Tiu CM, Wang Z, Yang HM, Chen TW, Yang WC. Mycotic aneurysm of the abdominal aorta in a patient undergoing hemodialysis: an unusual complication of Staphylococcus aureus bacteremia. Clin Infect Dis 2000; 30:823-4. [PMID: 10816154 DOI: 10.1086/313769] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
When Staphylococcus aureus is repeatedly positive in blood cultures even under effective antibiotics therapy (vancomycin, teicoplanin, or rifampin), computed tomography scan and sonography should be performed early to exclude mycotic aneurysm of the deeply seated arteries, especially in patients with abdominal aortic calcification. Before 1990, the most common causative organism of suprarenal aortic mycotic aneurysm was Salmonella; since 1990, it has been gram-positive cocci (i.e., Streptococcus and Staphylococcus) rather than gram-negative bacilli (i.e., Salmonella), possibly because of the more invasive procedures performed in clinical settings, but this hypothesis needs further investigation.
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Ng YY, Veenhuizen P, Lokhorst H, Staal FJ. Frape-1 and Frape-3: two different recombinant retroviruses encoding the same human marker gene. Cancer Gene Ther 2000; 7:624-8. [PMID: 10811481 DOI: 10.1038/sj.cgt.7700157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A major goal in retroviral-based gene therapy is to establish methods that allow for the selection and tracking of transduced cell populations. Ex vivo gene marking of normal and malignant hemopoietic cells allows the cells to be followed subsequently in vivo. For in vivo applications, a neutral marker gene that is nonimmunogenic is desirable. To track two distinctively treated cell populations in a single individual, we designed and constructed two retroviral vectors; both of these vectors encode a truncated form of the human low-affinity nerve growth factor receptor, a neutral gene that does not transduce signals and is expected to be nonimmunogenic in humans. The two vectors, named Frape-1 and Frape-3, are identical at the protein level but differ at the DNA level, containing restriction sites that allow easy detection by polymerase chain reaction analysis. We show that cell lines and primary CD34+ cells can be readily transduced with these vectors and that transduced cells can be distinguished by polymerase chain reaction- and vector-specific restriction sites. These vectors will be useful for toxicity studies on in vivo gene therapy and for determining the source of relapse in hematological malignancies.
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Ng YY, Fan JM, Mu W, Nikolic-Paterson DJ, Yang WC, Huang TP, Atkins RC, Lan HY. Glomerular epithelial-myofibroblast transdifferentiation in the evolution of glomerular crescent formation. Nephrol Dial Transplant 1999; 14:2860-72. [PMID: 10570089 DOI: 10.1093/ndt/14.12.2860] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Glomerular cellular crescents consist of epithelial cells and macrophages, which can undergo an irreversible process of fibrous organization. However, the origin of the fibroblast-type cells that mediate this fibrous organization is unclear. METHODS This study examined glomerular epithelial- myofibroblast transdifferentiation (GEMT) in the formation and evolution of glomerular crescents in two distinct rat models of glomerulonephritis: 5/6 nephrectomy and antiglomerular basement membrane (GBM) disease. RESULTS Early in the course of both disease models, and prior to crescent formation, immunohistochemistry staining and in-situ hybridization demonstrated de novo expression of alpha-smooth-muscle actin (alpha-SMA), a marker of smooth muscle cells and myofibroblasts, by glomerular parietal epithelial cells (GPEC). The expression of alpha-SMA by GPEC was accompanied by a loss of E-cadherin staining, a marker of epithelial cells. At this early stage of GEMT, ultrastructural studies identified the presence of characteristic actin microfilaments and dense bodies within GPEC which retained a normal epithelial morphology with apical-basal polarity and microvilli. A late stage of transdifferentiation was seen in fibrocellular crescents. In this case, GPEC attached to intact segments of the capsular basement membrane contained large bundles of actin microfilaments throughout the cell, and this was accompanied by a loss of polarity, microvilli, and tight junctions. There was a significant correlation between the presence of alpha-SMA(+) GPEC and glomerular crescent formation. Cellular crescents contained small numbers of alpha-SMA(+) myofibroblasts. These cells become the dominant population in fibrocellular crescents, which was associated with marked local proliferation. Relatively few alpha-SMA(+) myofibroblasts remained in fibrotic/organizing crescents. Most cells within cellular and fibrocellular crescents expressed transforming growth factor-beta (TGF-beta) and basic fibroblast growth factor (FGF-2), suggesting that these growth factors may regulate this GEMT process during the evolution of glomerular crescents. CONCLUSIONS This study provides the first phenotypic and morphological evidence that glomerular epithelial-myofibroblast transdifferentiation participates in the formation and evolution of glomerular crescents.
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Fan JM, Ng YY, Hill PA, Nikolic-Paterson DJ, Mu W, Atkins RC, Lan HY. Transforming growth factor-beta regulates tubular epithelial-myofibroblast transdifferentiation in vitro. Kidney Int 1999; 56:1455-67. [PMID: 10504497 DOI: 10.1046/j.1523-1755.1999.00656.x] [Citation(s) in RCA: 396] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND We recently found evidence of tubular epithelial-myofibroblast transdifferentiation (TEMT) during the development of tubulointerstitial fibrosis in the rat remnant kidney. This study investigated the mechanisms that induce TEMT in vitro. METHODS The normal rat kidney tubular epithelial cell line (NRK52E) was cultured for six days on plastic or collagen type I-coated plates in the presence or absence of recombinant transforming growth factor-beta1 (TGF-beta1). Transdifferentiation of tubular cells into myofibroblasts was assessed by electron microscopy and by expression of alpha-smooth muscle actin (alpha-SMA) and E-cadherin. RESULTS NRK52E cells cultured on plastic or collagen-coated plates showed a classic cobblestone morphology. Culture in 1 ng/ml TGF-beta caused only very minor changes in morphology, but culture in 10 or 50 ng/ml TGF-beta1 caused profound changes. This involved hypertrophy, a loss of apical-basal polarity and microvilli, with cells becoming elongated and invasive, the formation of a new front-end back-end polarity, and the appearance of actin microfilaments and dense bodies. These morphological changes were accompanied by phenotypic changes. Double immunohistochemistry staining showed that the addition of TGF-beta1 to confluent cell cultures caused a loss of the epithelial marker E-cadherin and de novo expression of alpha-SMA. An intermediate stage in transdifferentiation could be seen with hypertrophic cells expressing both E-cadherin and alpha-SMA. De novo alpha-SMA expression was confirmed by Northern blotting, Western blotting, and flow cytometry. In particular, cells with a transformed morphology showed strong alpha-SMA immunostaining of characteristic microfilament structures along the cell axis. There was a dose-dependent increase in the percentage of cells expressing alpha-SMA with increasing concentrations of TGF-beta1, which was completely inhibited by the addition of a neutralizing anti-TGF-beta1 antibody. Compared with growth on plastic, cell culture on collagen-coated plates showed a threefold increase in the percentage of cells expressing alpha-SMA in response to TGF-beta1. CONCLUSION TGF-beta1 is a key mediator that regulates, in a dose-dependent fashion, transdifferentiation of tubular epithelial cells into alpha-SMA+ myofibroblasts. This transdifferentiation is markedly enhanced by growth on collagen type I. These findings have identified a novel pathway that may contribute to renal fibrosis associated with overexpression of TGF-beta1 within the diseased kidney.
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MESH Headings
- Actins/genetics
- Animals
- Blotting, Northern
- Cadherins/genetics
- Cell Differentiation/drug effects
- Cell Line
- Collagen/pharmacology
- Epithelial Cells/cytology
- Epithelial Cells/drug effects
- Epithelial Cells/ultrastructure
- Fibroblasts/cytology
- Fibroblasts/drug effects
- Fibroblasts/ultrastructure
- Gene Expression/drug effects
- In Vitro Techniques
- Kidney Tubules/cytology
- Microscopy, Electron
- Microscopy, Electron, Scanning
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/ultrastructure
- Phenotype
- RNA, Messenger/analysis
- Rats
- Transforming Growth Factor beta/pharmacology
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Ng YY, Chang IT, Chen TW, Liou HN, Yang AH, Yang WC. Concomitant lupus nephritis and bullous eruption in systemic lupus erythematosus. Nephrol Dial Transplant 1999; 14:1739-43. [PMID: 10435885 DOI: 10.1093/ndt/14.7.1739] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Hou CC, Wu SC, Wu SC, Chen TW, Yang WC, Ng YY. Is serum transferrin receptor a sensitive marker of iron repletion in patients with iron-deficiency anemia and hemodialysis patients? ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1999; 62:189-94. [PMID: 10367478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
BACKGROUND Serum transferrin receptor (sTfR) concentration has been recognized as a reliable laboratory indicator of iron deficiency in recent years. But its response to iron supplementation has not been investigated. METHODS We evaluated the sTfR concentrations in 15 patients diagnosed with iron-deficiency anemia, in 30 patients receiving maintenance hemodialysis (HD) with iron repletion and in 31 healthy controls. The serial changes of sTfR concentration and their correlation with serum ferritin in patients with iron deficiency under iron repletion were also examined in three patients. RESULTS In patients with iron-deficiency anemia, the sTfR concentration was 5.6 +/- 2.4 mg/ml, significantly higher than that in the control group (1.8 +/- 0.4 mg/ml) and patients receiving maintenance HD with iron repletion (1.7 +/- 0.5 mg/ml). The three patients with iron-deficiency anemia who received eight to 16 weeks of iron supplementation showed steady and significant decreases in sTfR concentration and significant increases in serum ferritin and transferrin saturation. However, the decreases in sTfR concentration did not occur immediately, as did the increases in serum ferritin and transferrin saturation, following iron repletion. There was a four-week delayed response in the decrease of sTfR concentrations as measured against serum ferritin and transferrin saturation. CONCLUSIONS sTfR concentration may not be as effective as an early index of iron repletion compared with serum ferritin and transferrin saturation.
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Hussain HK, Ng YY, Wells CA, Courts M, Nockler IB, Curling OM, Carpenter R, Perry NM. The significance of new densities and microcalcification in the second round of breast screening. Clin Radiol 1999; 54:243-7. [PMID: 10210344 DOI: 10.1016/s0009-9260(99)91159-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
AIM To assess the nature of new densities and microcalcifications in the second round of breast screening. MATERIALS AND METHODS A total of 34 634 women were screened at our unit in the second round of the United Kingdom National Health Service Breast Screening Programme. Of those attending for the second time, 302 were recalled for further work-up of 311 new lesions. The lesions were divided into masses, microcalcifications, asymmetric densities and architectural distortions. Masses were classified according to margin and density, and microcalcifications according to morphology and distribution. RESULTS Among women attending for the second time, the cancer detection rate was 0.45% (89 cancers). One hundred and eighty-eight new masses were identified: 53 well-defined (two malignant), 67 partially defined (six malignant), 54 ill-defined (18 malignant), and 14 spiculate (14 malignant). Well-defined masses were usually cysts, especially in women on hormone replacement therapy. Of 97 new microcalcifications, 71 were pleomorphic (28 malignant), 12 linear (one malignant), and 14 punctate (none malignant). Twenty-five new asymmetric densities were identified (five malignant). One of two architectural distortions was malignant. Malignancy was found in 21% of new masses, 30% of new microcalcification and 20% of asymmetric densities. CONCLUSION Carcinoma was found in 24% of all new mammographic abnormalities appearing in a 3-year screening period. Spiculate and ill-defined masses, clustered pleomorphic microcalcification, and new asymmetric densities should be regarded with particular suspicion. The use of fine needle aspiration cytology in combination with imaging assessment may help to reduce the number of benign excisional biopsies for new mammographic lesions.
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Lee CC, Chou YH, Chen TW, Wu TH, Charng YP, Chiou HJ, Tiu CM, Yang WC, Ng YY. Engorgement of brachiocephalic vein after creation of an AV fistula--a result of sternoclavicular joint osteophyte. Nephrol Dial Transplant 1999; 14:757-9. [PMID: 10193835 DOI: 10.1093/ndt/14.3.757] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Chang YP, Chen TW, Chen CP, Ng YY, Yang WC. Inguinal abscess in a CAPD patient secondary to inguinal hernia and repeated episodes of peritonitis: a case report. Perit Dial Int 1999; 19:177-8. [PMID: 10357193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
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Lin CC, Chen TW, Ng YY, Chou YH, Yang WC. Thyroid dysfunction and nodular goiter in hemodialysis and peritoneal dialysis patients. ARCH ESP UROL 1998; 18:516-21. [PMID: 9848631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
OBJECTIVE To investigate the prevalence of nodular goiter and thyroid dysfunction in uremic patients undergoing hemodialysis (HD) and peritoneal dialysis. DESIGN Cross-sectional study. SETTING Single dialysis unit and outpatient clinic. PATIENTS The study included 221 patients [143 HD and 78 continuous ambulatory peritoneal dialysis (CAPD) patients] along with 135 consecutively selected outpatients as controls. MAIN OUTCOME MEASURES Ultrasonography was used to detect patients' thyroid function and nodular goiter. RESULTS Nodular goiter was detected in 54.8% of the uremic patients and in 21.5% of the controls. Uremic patients had higher prevalence of thyroid dysfunction, which included reduced serum concentration of total T3, total T4, and free T4, and increased serum level of TSH. Hypothyroidism was also observed more frequently in uremic patients than in the control group (5.4% vs 0.7%, p < 0.05). Nodular goiter was more frequently found in females than in males (63.5% vs 48%, p < 0.05). Moreover, the prevalence of nodular goiter increased with age (p < 0.02) in uremic patients. Hemodialysis patients had a higher frequency of reduced total T3 level (46.9% vs 29.5%, p < 0.02). However, CAPD patients had lower T4 levels (6.23+/-1.82 microg/dL vs 7.15+/-1.99 microg/dL, p < 0.05). CONCLUSION Because of the high incidence of hypothyroidism and nodular goiter in uremic patients, screening of thyroid function and goiter detection with ultrasound should be considered in evaluation of end-stage renal disease patients.
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Ng YY, Huang TP, Yang WC, Chen ZP, Yang AH, Mu W, Nikolic-Paterson DJ, Atkins RC, Lan HY. Tubular epithelial-myofibroblast transdifferentiation in progressive tubulointerstitial fibrosis in 5/6 nephrectomized rats. Kidney Int 1998; 54:864-76. [PMID: 9734611 DOI: 10.1046/j.1523-1755.1998.00076.x] [Citation(s) in RCA: 307] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Tubulointerstitial fibrosis is the final common pathway to end-stage renal failure. The present study investigated the potential role of tubular epithelial cells (TEC) in progressive fibrosis in the rat remnant kidney model. METHODS Rats underwent 5/6 nephrectomy or a sham operation (control), and groups of six animals were killed at weeks 1, 3, 5, 9, 13, 17 and 21. RESULTS Immunohistochemistry staining and in situ hybridization at week 3 after nephrectomy demonstrated de novo expression of alpha-smooth muscle actin (alpha-SMA)--a marker of smooth muscle cells and myofibroblasts--by TEC that was invariably associated with disruption of the tubular basement membrane (TBM). This phenotypic evidence of tubular epithelial-myofibroblast transdifferentiation was supported by ultrastructural studies identifying the presence of characteristic actin microfilaments and dense bodies within TEC with a transformed morphology. In the late stage of this apparent tubular epithelial-myofibroblast transdifferentiation, TEC lost apical-basal polarity and tight junctions, became elongated, detached from the TBM, separated from neighboring cells and appeared to migrate into the peritubular interstitium through the damaged basement membrane. Indeed, focal peritubular accumulation of alpha-SMA+ myofibroblasts and local tubulointerstitial fibrosis was closely associated with alpha-SMA+ tubules, suggesting a tubular epithelial origin for some of these cells. Quantitative analysis found a significant correlation between the number of alpha-SMA+ TEC and the accumulation of interstitial alpha-SMA+ myofibroblasts and the severity of tubulointerstitial fibrosis (both P < 0.001). CONCLUSIONS This study provides phenotypic and morphological evidence to support the hypothesis that TEC are pro-fibrogenitor cells capable of tubular epithelial-myofibroblast transdifferentiation in progressive renal fibrosis. In addition, we postulate that disruption of the TBM, which facilitates epithelial cell contact with the interstitial matrix, promotes this process of transdifferentiation.
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Ng YY, Yu S, Chen TW, Wu SC, Yang AH, Yang WC. Interstitial renal fibrosis in a young woman: association with a Chinese preparation given for irregular menses. Nephrol Dial Transplant 1998; 13:2115-7. [PMID: 9719178 DOI: 10.1093/ndt/13.8.2115] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Hou CC, Wu SC, Wu SC, Yang WC, Huang TP, Ng YY. Serum transferrin receptor concentration is not indicative of erythropoietic activity in chronic hemodialysis patients with poor response to recombinant human erythropoietin. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1998; 61:456-62. [PMID: 9745161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Serum transferrin receptor (sTfR) is a transmembrane glycoprotein derived from erythroid precursors in the bone marrow. Its concentration provides a quantitative measure of total erythropoietic activity and an indication of functional iron deficiency. This study was conducted to investigate whether sTfR is a useful index of erythropoietic activity in chronic hemodialysis patients with poor response to maintenance recombinant human erythropoietin (rHuEPO) therapy. METHODS Using an enzyme-linked immunosorbent assay, sTfR concentration was measured in 67 uremic patients who had been on hemodialysis for a mean of 42 months (3-242 months). rHuEPO was administered three times a week to keep the hematocrit above 30%. Hemoglobin, red blood cell indices, serum ferritin, serum total iron binding capacity and unsaturated iron binding capacity were determined. Of the 67 patients, 35 who responded favorably to rHuEPO with hematocrits above 30% were categorized as Group I and 32 who did not attain the target hematocrit were categorized as Group II. As a control group, 31 healthy subjects were also investigated. RESULTS The serum iron, ferritin, transferrin iron saturation, dialysis efficiency and nutritional state were not different between groups of hemodialysis patients. The mean sTfR concentration was 2.1 +/- 0.6 micrograms/ml (range, 1.15-3.53 micrograms/ml) in Group I patients, compared with 1.9 +/- 0.9 micrograms/ml (range, 1.03-2.65 micrograms/ml) in Group II. The difference was not significant. In addition, the mean sTfR concentration of 1.8 +/- 0.4 micrograms/ml (range, 0.86-2.76 micrograms/ml) in the healthy controls was not significantly different from Groups I and II. CONCLUSIONS sTfR concentration cannot be used to distinguish good from poor rHuEPO responders among chronic hemodialysis patients who have elevated serum ferritin (> 300 micrograms/l) and transferrin iron saturation (> 25%) during the course of maintenance rHuEPO therapy.
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Yang N, Wu LL, Nikolic-Paterson DJ, Ng YY, Yang WC, Mu W, Gilbert RE, Cooper ME, Atkins RC, Lan HY. Local macrophage and myofibroblast proliferation in progressive renal injury in the rat remnant kidney. Nephrol Dial Transplant 1998; 13:1967-74. [PMID: 9719149 DOI: 10.1093/ndt/13.8.1967] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND We have recently shown that blockade of angiotensin II activity inhibits local macrophage and myofibroblast proliferation in progressive non-immune renal injury in the rat remnant kidney. However, it is not known whether this local proliferation contributes to macrophage and myofibroblast accumulation and the development of renal injury. Therefore, we examined this issue in a detailed time-course study of the rat remnant kidney. METHODS Groups of five rats were killed 4, 8,12 or 16 weeks after 5/6 subtotal nephrectomy (STNx) or a sham operation. Macrophage and myofibroblast proliferation was assessed by two-colour immunostaining for ED1+ macrophages or alpha-smooth muscle actin (alpha-SMA)-positive myofibroblasts with the proliferating cell nuclear antigen (PCNA) or bromodeoxyuridine. RESULTS All parameters of renal function and histology remained normal in the sham-operated controls, and no macrophage or myofibroblast accumulation was evident. In contrast, prominent macrophage accumulation developed in both the glomerulus and tubulointerstitium in STNx animals, peaking at week 12. Many ED1+ macrophages showed PCNA expression, accounting for 19-34% of the total macrophage population. There was a highly significant correlation between proliferating macrophages and total macrophage accumulation in the glomerulus (r = 0.82, P < 0.0001) and tubulointerstitium (r = 0.70, P < 0.001). Macrophage proliferation was largely restricted to focal areas of renal damage, such as glomerular segmental lesions and severe tubulointerstitial damage. Also, the subpopulation of proliferating macrophages gave a highly significant correlation with loss of renal function, proteinuria, and glomerular and tubulointerstitial lesions. In addition, many alpha-SMA myofibroblasts were evident within expanded mesangial areas and the tubulointerstitium following STNx. Interestingly, active lesions contained many large alpha-SMA+ cells double-stained for PCNA, accounting for 24-29% of total myofibroblasts. There was a highly significant correlation between the number of proliferating myofibroblasts and total myofibroblast accumulation during the evolution of this disease, and both populations correlated with progressive renal injury. CONCLUSIONS This study has shown that local proliferation is an important mechanism in both macrophage and myofibroblast accumulation during the development of renal injury in the rat remnant kidney. In addition, local macrophage proliferation is postulated as a mechanism for amplifying kidney damage in nonimmune renal injury.
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Giess CS, Keating DM, Osborne MP, Ng YY, Rosenblatt R. Retroareolar breast carcinoma: clinical, imaging, and histopathologic features. Radiology 1998; 207:669-73. [PMID: 9609889 DOI: 10.1148/radiology.207.3.9609889] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate the clinical, imaging, and histopathologic features of breast carcinoma in the retroareolar tissues and to determine whether there are any characteristics common to this location. MATERIALS AND METHODS Thirty-five patients (age range, 38-77 years) with 37 retroareolar carcinomas were identified retrospectively. Retroareolar carcinoma was defined as that within 2 cm of the nipple-areolar complex. Mammographically occult tumors were identified by using histopathologic records (n = 4) or clinical examination findings (n = 6). RESULTS Twenty-nine (78%) tumors had clinical findings, including palpable mass (n = 29), associated nipple inversion or retraction (n = 4), and associated nipple discharge (n = 2). Twenty-seven (73%) tumors had mammographic findings of mass (n = 16), mass with calcifications (n = 5), and microcalcifications (n = 6; four of these microcalcifications were associated with a mammographically occult palpable mass). Ultrasound was performed in 17 tumors, all of which were hypoechoic. The stage of 31 carcinomas was known: one was stage 0, 17 were stage I, and 13 were stage II. Histopathologic analysis revealed 35 ductal carcinomas and two invasive lobular carcinomas. CONCLUSION Retroareolar carcinoma usually manifests as a palpable mass. Mammography is less sensitive in this area than in other areas of the breast. Ultrasound can be a valuable adjunct in the assessment of retroareolar malignancy.
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Yang N, Nikolic-Paterson DJ, Ng YY, Mu W, Metz C, Bacher M, Meinhardt A, Bucala R, Atkins RC, Lan HY. Reversal of established rat crescentic glomerulonephritis by blockade of macrophage migration inhibitory factor (MIF): potential role of MIF in regulating glucocorticoid production. Mol Med 1998; 4:413-24. [PMID: 10780884 PMCID: PMC2230272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Macrophage migration inhibitory factor (MIF) is a potent pro-inflammatory cytokine that also counter-regulates glucocorticoid action. We investigated whether immunoneutralization of MIF could reverse established experimental crescentic glomerulonephritis and if this treatment could modulate endogenous glucocorticoid levels. Accelerated anti-GBM glomerulonephritis was induced in six littermate pairs of rats. Once crescentic disease was established on day 7, one animal in each pair was given a daily injection of neutralizing anti-MIF antibody (Ab) or irrelevant isotype control Ab for 14 days and then killed on day 21. In addition, a group of 6 animals was killed on day 7 of disease without any treatment. Animals receiving the control Ab exhibited a rapidly progressive glomerulonephritis with severe renal injury (proteinuria), loss of renal function (creatinine clearance), anemia, and marked histologic damage (including glomerular crescent formation), compared with animals killed on day 7 without treatment. In contrast, anti-MIF Ab treatment partially reversed the disease by restoring normal renal function and reducing histological damage compared with untreated animals killed on day 7 (p < 0.05). Interestingly, anti-MIF Ab treatment also prevented severe anemia (p < 0.05). Reversal of disease was associated with a significant reduction in leukocyte infiltration and activation and renal interleukin-1 (IL-1) production. Importantly, anti-MIF Ab treatment caused a significant increase in endogenous serum corticosterone levels, which correlated with the reversal of disease parameters. In conclusion, this study has demonstrated that blocking MIF activity can partially reverse established crescentic glomerulonephritis and suggests that MIF operates by both enhancing the cellular immune response and suppressing the endogenous anti-inflammatory glucocorticoid response.
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Chang IT, Chen TW, Ng YY, Yang WC. Recurrent intestinal angiodysplastic bleeding in a patient on hemodialysis ceasing spontaneously with CAPD. ARCH ESP UROL 1998; 18:342-3. [PMID: 9663905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Hsu YH, Ng YY, Yang AH, Chen TW, Huang TP. Focal segmental glomerulosclerosis after poststreptococcal glomerulonephritis in the elderly: a case report. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1998; 61:301-5. [PMID: 9650435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Acute poststreptococcal glomerulonephritis (PSGN) is quite rare in the elderly population. It is very difficult to recognize because the initial symptoms are similar to those of more common diseases of this age group. Compared with younger patients, elderly patients with PSGN tend to have a high incidence of renal function impairment and anuria or prolonged oliguria. Recovery from acute PSGN in the elderly is less predictable than in children and younger adults, especially when associated with severe impairment of renal function. We present the case of an elderly patient with PSGN, who had a skin infection of the face and anuria on admission. Percutaneous left renal biopsy was performed in the initial hospitalization period and in the recovery phase of the disease. Renal function recovered within two months. However, increased urinary white blood cell sediments with normal serum creatinine concentrations persisted in the successive three years of follow-up. Renal biopsy was repeated and showed evidence of focal segmental glomerulosclerosis.
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Hou CC, Lee YJ, Yu KW, Yang WC, Chen TW, Ng YY. Peritonitis due to Listeria monocytogenes in a patient receiving maintenance hemodialysis. Clin Infect Dis 1998; 26:514-6. [PMID: 9502491 DOI: 10.1086/517103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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