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Cao LC, Martin V, Linh LTK, Giang TT, Chau NTM, Anh TNP, Nghia VX, The NT, My TN, Sy BT, Toan NL, Song LH, Bock CT, Velavan TP. High Hepatitis E Virus (HEV) Seroprevalence and No Evidence of HEV Viraemia in Vietnamese Blood Donors. Viruses 2023; 15:2075. [PMID: 37896852 PMCID: PMC10611202 DOI: 10.3390/v15102075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 10/02/2023] [Accepted: 10/06/2023] [Indexed: 10/29/2023] Open
Abstract
The prevalence of hepatitis E virus (HEV) in the Vietnamese population remains underestimated. The aim of the present study was to investigate the seroprevalence of HEV IgG/IgM antibodies and the presence of HEV RNA in blood donors as a part of epidemiological surveillance for transfusion-transmitted viruses. Serum samples from blood donors (n = 553) were analysed for markers of past (anti-HEV IgG) and recent/ongoing (anti-HEV IgM) HEV infections. In addition, all serum samples were subsequently tested for HEV RNA positivity. The overall prevalence of anti-HEV IgG was 26.8% (n = 148/553), while the seroprevalence of anti-HEV IgM was 0.5% (n = 3/553). Anti-HEV IgG seroprevalence in male and female donors was similar (27.1% and 25.5%, respectively). A higher risk of hepatitis E exposure was observed with increasing age. None of the blood donors were HEV RNA positive, and there was no evidence of HEV viraemia. Although the absence of HEV viraemia in blood donors from Northern Vietnam is encouraging, further epidemiological surveillance in other geographical regions is warranted to rule out transfusion-transmitted HEV.
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Affiliation(s)
- Le Chi Cao
- Institute of Tropical Medicine, University of Tübingen, 72074 Tübingen, Germany; (L.C.C.); (V.M.); (L.T.K.L.)
- Department of Parasitology, Hue University of Medicine and Pharmacy (HUMP), Hue University, Hue 49000, Vietnam; (T.T.G.); (N.T.M.C.); (T.N.P.A.)
| | - Vanessa Martin
- Institute of Tropical Medicine, University of Tübingen, 72074 Tübingen, Germany; (L.C.C.); (V.M.); (L.T.K.L.)
| | - Le Thi Kieu Linh
- Institute of Tropical Medicine, University of Tübingen, 72074 Tübingen, Germany; (L.C.C.); (V.M.); (L.T.K.L.)
- Vietnamese-German Center for Medical Research (VG-CARE), Hanoi 10000, Vietnam; (N.T.T.); (T.N.M.); (B.T.S.); (L.H.S.)
| | - Tran Thi Giang
- Department of Parasitology, Hue University of Medicine and Pharmacy (HUMP), Hue University, Hue 49000, Vietnam; (T.T.G.); (N.T.M.C.); (T.N.P.A.)
| | - Ngo Thi Minh Chau
- Department of Parasitology, Hue University of Medicine and Pharmacy (HUMP), Hue University, Hue 49000, Vietnam; (T.T.G.); (N.T.M.C.); (T.N.P.A.)
| | - Ton Nu Phuong Anh
- Department of Parasitology, Hue University of Medicine and Pharmacy (HUMP), Hue University, Hue 49000, Vietnam; (T.T.G.); (N.T.M.C.); (T.N.P.A.)
| | - Vu Xuan Nghia
- 108 Military Central Hospital, Hanoi 10000, Vietnam;
| | - Nguyen Trong The
- Vietnamese-German Center for Medical Research (VG-CARE), Hanoi 10000, Vietnam; (N.T.T.); (T.N.M.); (B.T.S.); (L.H.S.)
- 108 Military Central Hospital, Hanoi 10000, Vietnam;
| | - Truong Nhat My
- Vietnamese-German Center for Medical Research (VG-CARE), Hanoi 10000, Vietnam; (N.T.T.); (T.N.M.); (B.T.S.); (L.H.S.)
| | - Bui Tien Sy
- Vietnamese-German Center for Medical Research (VG-CARE), Hanoi 10000, Vietnam; (N.T.T.); (T.N.M.); (B.T.S.); (L.H.S.)
- 108 Military Central Hospital, Hanoi 10000, Vietnam;
| | - Nguyen Linh Toan
- Department of Pathophysiology, Vietnam Military Medical University, Hanoi 10000, Vietnam;
| | - Le Huu Song
- Vietnamese-German Center for Medical Research (VG-CARE), Hanoi 10000, Vietnam; (N.T.T.); (T.N.M.); (B.T.S.); (L.H.S.)
- 108 Military Central Hospital, Hanoi 10000, Vietnam;
| | - C.-Thomas Bock
- Institute of Tropical Medicine, University of Tübingen, 72074 Tübingen, Germany; (L.C.C.); (V.M.); (L.T.K.L.)
- Division of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Department of Infectious Diseases, Robert Koch Institute, 13353 Berlin, Germany
| | - Thirumalaisamy P. Velavan
- Institute of Tropical Medicine, University of Tübingen, 72074 Tübingen, Germany; (L.C.C.); (V.M.); (L.T.K.L.)
- Vietnamese-German Center for Medical Research (VG-CARE), Hanoi 10000, Vietnam; (N.T.T.); (T.N.M.); (B.T.S.); (L.H.S.)
- Faculty of Medicine, Duy Tan University, Danang 550000, Vietnam
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Ngo TMC, Nu PAT, Cao LC, Ha TNT, Do TBT, Thi GT. A case of onychomycosis caused by a terbinafine-susceptible Fusarium solani in Vietnam. Iran J Microbiol 2022; 14:932-936. [PMID: 36721449 PMCID: PMC9867615 DOI: 10.18502/ijm.v14i6.11269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fusarium spp. are the common onychomycosis pathogens in non-dermatophyte molds, and are considered resistant to many antifungal agents. We reported onychomycosis of the fingernail caused by Fusarium solani in Vietnam. The minimum inhibitory concentration of terbinafine against the tested isolate was 1μg/ml, which was the lowest of all antimycotic agents. The patient was successfully treated with a daily dose of 250mg terbinafine for two months, and no recurrence occurred after a one-year follow-up. Antifungal susceptibility testing is recommended in Fusarium onychomycosis.
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Affiliation(s)
- Thi Minh Chau Ngo
- Corresponding author: Thi Minh Chau Ngo, MD, Ph.D, Department of Parasitology, Hue University of Medicine and Pharmacy, Hue University, Hue, Viet Nam. Tel: +84983863426
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Ton Nu PA, Ngo TMC, Nguyen Phuoc V, Dang Nhu T, Do Ngoc A, Cao LC. Biliary fascioliasis – A rare differential diagnosis of biliary obstruction. J Infect Dev Ctries 2022; 16:1664-1667. [DOI: 10.3855/jidc.16037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 07/25/2022] [Indexed: 11/06/2022] Open
Abstract
Fascioliasis is a zoonotic disease caused by Fasciola hepatica or F. gigantica. There are two phases of Fasciola infection. In the acute phase, the patient has a wide spectrum of clinical manifestations while the later phase of infection is usually related to inflammatory changes in the bile duct and the mechanical effects of the worm, which can lead to biliary obstruction. The presence of Fasciola inside the biliary system has rarely been reported in the literature. In this report, we presented a case of bile duct obstruction in a 36-year-old male patient undergoing cholecystectomy for gallstones and with a history of worsening jaundice for one month. Extensive laboratory testing failed to clarify the cause of jaundice. Three living liver flukes were subsequently retrieved from the right hepatic duct and later confirmed as F. gigantica by morphology and internal transcribed spacer (ITS2) sequence analysis.
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Margarita V, Cao LC, Bailey NP, Ngoc THT, Ngo TMC, Nu PAT, Diaz N, Dessì D, Hirt RP, Fiori PL, Rappelli P. Effect of the Symbiosis with Mycoplasma hominis and Candidatus Mycoplasma Girerdii on Trichomonas vaginalis Metronidazole Susceptibility. Antibiotics (Basel) 2022; 11:antibiotics11060812. [PMID: 35740218 PMCID: PMC9220282 DOI: 10.3390/antibiotics11060812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/14/2022] [Accepted: 06/15/2022] [Indexed: 11/16/2022] Open
Abstract
Trichomoniasis, the most common non-viral sexually transmitted infection worldwide, is caused by the protozoon Trichomonas vaginalis. The 5- nitroimidazole drugs, of which metronidazole is the most prescribed, are the only effective drugs to treat trichomoniasis. Resistance against metronidazole is increasingly reported among T. vaginalis isolates. T. vaginalis can establish an endosymbiosis with two Mycoplasma species, Mycoplasma hominis and Candidatus Mycoplasma girerdii, whose presence has been demonstrated to influence several aspects of the protozoan pathobiology. The role of M. hominis in T. vaginalis resistance to metronidazole is controversial, while the influence of Ca. M. girerdii has never been investigated. In this work, we investigate the possible correlation between the presence of Ca. M. girerdii and/or M. hominis and the in vitro drug susceptibility in a large group of T. vaginalis isolated in Italy and in Vietnam. We also evaluated, via RNA-seq analysis, the expression of protozoan genes involved in metronidazole resistance in a set of syngenic T. vaginalis strains, differing only for the presence/absence of the two Mycoplasmas. Our results show that the presence of M. hominis significantly increases the sensitivity to metronidazole in T. vaginalis and affects gene expression. On the contrary, the symbiosis with Candidatus Mycoplasma girerdii seems to have no effect on metronidazole resistance in T. vaginalis.
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Affiliation(s)
- Valentina Margarita
- Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43/B, 07100 Sassari, Italy; (V.M.); (N.D.); (D.D.); (P.L.F.)
| | - Le Chi Cao
- Department of Parasitology, Hue University of Medicine and Pharmacy, 06 Ngo Quyen Street, Hue 49000, Vietnam; (L.C.C.); (T.H.T.N.); (T.M.C.N.); (P.A.T.N.)
| | - Nicholas P. Bailey
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK; (N.P.B.); (R.P.H.)
| | - Thuy Ha Thi Ngoc
- Department of Parasitology, Hue University of Medicine and Pharmacy, 06 Ngo Quyen Street, Hue 49000, Vietnam; (L.C.C.); (T.H.T.N.); (T.M.C.N.); (P.A.T.N.)
| | - Thi Minh Chau Ngo
- Department of Parasitology, Hue University of Medicine and Pharmacy, 06 Ngo Quyen Street, Hue 49000, Vietnam; (L.C.C.); (T.H.T.N.); (T.M.C.N.); (P.A.T.N.)
| | - Phuong Anh Ton Nu
- Department of Parasitology, Hue University of Medicine and Pharmacy, 06 Ngo Quyen Street, Hue 49000, Vietnam; (L.C.C.); (T.H.T.N.); (T.M.C.N.); (P.A.T.N.)
| | - Nicia Diaz
- Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43/B, 07100 Sassari, Italy; (V.M.); (N.D.); (D.D.); (P.L.F.)
| | - Daniele Dessì
- Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43/B, 07100 Sassari, Italy; (V.M.); (N.D.); (D.D.); (P.L.F.)
- Mediterranean Centre for Disease Control (MCDC), 07110 Sassari, Italy
| | - Robert P. Hirt
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK; (N.P.B.); (R.P.H.)
| | - Pier Luigi Fiori
- Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43/B, 07100 Sassari, Italy; (V.M.); (N.D.); (D.D.); (P.L.F.)
- Mediterranean Centre for Disease Control (MCDC), 07110 Sassari, Italy
| | - Paola Rappelli
- Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43/B, 07100 Sassari, Italy; (V.M.); (N.D.); (D.D.); (P.L.F.)
- Mediterranean Centre for Disease Control (MCDC), 07110 Sassari, Italy
- Correspondence:
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Wang Y, Liu YQ, Li XL, Cao LC, Wei DC, Zhang HL, Shi DC, Yu G. Large-scale growth and characteristics of N-doped carbon nanotubes with ultra-large cavity. J Nanosci Nanotechnol 2009; 9:1076-1079. [PMID: 19441459 DOI: 10.1166/jnn.2009.c091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
N-doped carbon nanotubes (CNTs) with ultra-large cavity have been synthesized by using a mixture of ZnO and graphite as catalyst in the floating catalyst method. The as-synthesized N-doped CNTs are very pure, and a striking characteristic structure is that the outer diameter is at least 10 times larger than the wall thickness. Moreover, electronic properties analysis reveals that the N-doped CNTs with ultra-large cavity have a reduced room temperature resistance compared with those of the common N-doped CNTs, which give an experimental prove for the previous theoretical predictions.
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Affiliation(s)
- Y Wang
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
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Qingzhen X, Cao LC, Xin ZX. EL-003 NF-κB regulates expressions of matrix metalloproteinase-2 and 9 in human cytotrophoblastic cells from the first trimester placenta in vitro. Reprod Biomed Online 2006. [DOI: 10.1016/s1472-6483(11)60528-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Scheid C, Honeyman T, Kohjimoto Y, Cao LC, Jonassen J. Oxalate-induced changes in renal epithelial cell function: role in stone disease. Mol Urol 2001; 4:371-82. [PMID: 11156705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Many studies on the etiology of stone disease have focused on the properties of urine that affect crystal nucleation and growth. More recent studies have focused on the properties of the renal epithelium and the role of injury in crystal retention. The latter studies have shown that oxalate exposure per se can damage renal epithelial cells and enhance crystal binding. This overview summarizes findings of specific biochemical and genetic alterations observed in renal epithelial cells after exposure to oxalate. In LLC-PK1 and MDCK cells, oxalate exposure produces marked effects on membranes, causing a redistribution of phosphatidylserine and activation of two lipid signaling cascades, one involving phospholipase A(2) (PLA(2)) and one involving ceramide. Longer exposure to oxalate leads to membrane damage and cell death. Adaptive responses are also observed, including proliferation (for replacement of damaged cells) and induction of various genes (for cellular replacement and repair). Many or all of these responses are blocked by antioxidants, and many can be mimicked by PLA(2) agonists/products. This finding suggests links between oxalate-induced increases in oxidant stress, lipid signaling pathways, and subsequent molecular responses that may eventuate in renal cell damage or death. Whether such changes play a role in stone disease in vivo, and whether strategies to inhibit these changes would be beneficial therapeutically, is unknown.
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Affiliation(s)
- C Scheid
- Department of Physiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
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Cao LC, Jonassen J, Honeyman TW, Scheid C. Oxalate-induced redistribution of phosphatidylserine in renal epithelial cells: implications for kidney stone disease. Am J Nephrol 2001; 21:69-77. [PMID: 11275638 DOI: 10.1159/000046224] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
AIMS The present studies assessed the possibility that exposure to oxalate leads to alterations in membrane structure that promote crystal binding to renal epithelial cells. Specifically, we determined whether oxalate exposure produces a redistribution of membrane phosphatidylserine (PS) and an increase in the binding of (14)C-oxalate crystals to renal epithelial cells. METHODS PS distribution was monitored in MDCK cells and in phospholipid-containing vesicles using NBD-PS, a fluorescent derivative of PS. Superficial PS was also detected by monitoring the binding of annexin V to MDCK cells. RESULTS Oxalate exposure rapidly increased the abundance of superficial NBD-PS and increased the binding of annexin V to MDCK cells. Oxalate exposure also increased PS at the surface of phospholipid vesicles, suggesting that oxalate may interact directly with PS. The oxalate concentrations that increased superficial PS also increased binding of (14)C-oxalate crystals to MDCK cells, and the increased crystal binding was blocked by annexin V. CONCLUSIONS These findings provide direct evidence that oxalate exposure promotes both a redistribution of PS and an increase in crystal binding in renal epithelial cells and support the notion that oxalate toxicity may contribute to the development of stone disease by altering the properties of the renal epithelial cell membrane.
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Affiliation(s)
- L C Cao
- Department of Physiology, University of Massachusetts Medical Center, Worcester, Mass., USA
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Abstract
BACKGROUND Oxalate exposure produces oxidant stress in renal epithelial cells leading to death of some cells and adaptation of others. The pathways involved in these diverse actions remain unclear, but appear to involve activation of phospholipase A2 (PLA2) and redistribution of membrane phospholipids. The present studies examined the possibility that oxalate actions may also involve increased accumulation of ceramide, a lipid-signaling molecule implicated in a variety of pathways, including those leading to apoptotic cell death. METHODS Ceramide accumulation was examined in renal epithelial cells from pig kidney (LLC-PK1 cells) and from dog kidney [Madin-Darby canine kidney (MDCK cells)] using the diacylglycerol kinase assay. Sphingomyelin degradation was assessed by monitoring the disappearance of 3H-sphingomyelin from cells that had been prelabeled with [3H]-choline. The effects of oxalate were compared with those of other oxidants (peroxide, xanthine/xanthine oxidase), other organic acids (formate and citrate), and a known activator of sphingomyelinase in these cells [tumor necrosis factor-alpha (TNF-alpha)]. Separate studies determined whether oxalate-induced accumulation of ceramide could be blocked by pretreatment with antioxidants [Mn (III) tetrakis (1-methyl-4-pyridyl) porphyrin (Mn TMPyP, a superoxide dismutase mimetic) or N-acetylcysteine (NAC; an antioxidant)], with an inhibitor of ceramide synthase [fumonisin B1 (FB1)] or with an inhibitor of PLA2 [arachidonyl trifluoromethylketone (AACOCF3)]. RESULTS Oxalate exposure produced a significant time- and concentration-dependent increase in cellular ceramide. A reciprocal decrease in 3H-sphingomyelin was observed under these conditions. Increases in cellular ceramide levels were also observed after treatment with other oxidants (hydrogen peroxide, and xanthine/xanthine oxidase), activators of sphingomyelinase (TNF-alpha), exogenous sphingomyelinase, or arachidonic acid. Formate produced similar (albeit smaller) effects, and citrate did not. The oxidant-induced increases in ceramide were attenuated by pretreatment with NAC (a glutathione precursor) and MnTMPyP (a superoxide dismutase mimetic), suggesting a role for cellular redox states. The oxalate-induced increase in ceramide was also attenuated by pretreatment with AACOCF3, suggesting a role for PLA2. Pretreatment with FB1 produced a small but statistically insignificant attenuation of the response to oxalate. CONCLUSIONS Oxalate exposure produces a marked accumulation of ceramide in renal epithelial cells by a process that is redox sensitive and mediated in part by activation of PLA2. Since cellular sphingomyelin decreased as ceramide increased, it seems likely that oxalate actions are mediated, at least in part, by an increase in sphingomyelinase activity, although alterations in ceramide synthase are also possible. Further study is required to define the steps involved in oxalate actions and to determine the extent to which ceramide signaling mediates oxalate actions.
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Affiliation(s)
- L C Cao
- Department of Physiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0127, USA
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Miller C, Kennington L, Cooney R, Kohjimoto Y, Cao LC, Honeyman T, Pullman J, Jonassen J, Scheid C. Oxalate toxicity in renal epithelial cells: characteristics of apoptosis and necrosis. Toxicol Appl Pharmacol 2000; 162:132-41. [PMID: 10637137 DOI: 10.1006/taap.1999.8835] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Studies in various tissues, including the kidney, have demonstrated that toxins elicit apoptosis under certain conditions and necrosis under others. The nature of the response has important consequences for the injured tissue in that necrotic cells elicit inflammatory responses, whereas apoptotic cells do not. Thus, there has been considerable interest in defining the mode of cell death elicited by known cytotoxins. The present studies examined the response of renal epithelial cells to oxalate, a metabolite excreted by the kidney that produces oxidant stress and death of renal cells at pathophysiological concentrations. These studies employed LLC-PK1 cells, a renal epithelial cell line from pig kidney and NRK-52E (NRK) cells, a line from normal rat kidney, and compared the effects of oxalate with those of known apoptotic agents. Changes in cellular and nuclear morphology, in nuclear size, in ceramide production, and in DNA integrity were assessed. The ability of bcl-2, an anti-apoptotic gene product, to attenuate oxalate toxicity was also assessed. These studies indicated that oxalate-induced death of renal epithelial cells exhibits several features characteristic of apoptotic cell death, including increased production of ceramide, increased abundance of apoptotic bodies, and marked sensitivity to the level of expression of the anti-apoptotic gene bcl-2. Oxalate-induced cell death also exhibits several characteristics of necrotic cell death in that the majority of the cells exhibited cellular and nuclear swelling after oxalate treatment and showed little evidence of DNA cleavage by TUNEL assay. These results suggest that toxic concentrations of oxalate trigger both forms of cell death in renal epithelial cells.
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Affiliation(s)
- C Miller
- Department of Physiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA
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Cao LC, Deng G, Boevé ER, de Bruijn WC, de Water R, Verkoelen CF, Romijn JC, Schröder FH. Zeta potential measurement and particle size analysis for a better understanding of urinary inhibitors of calcium oxalate crystallization. Scanning Microsc 1998; 10:401-11; discussion 412-4. [PMID: 9813619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
To better understand urinary inhibitors of calcium oxalate crystallization, both zeta potential measurement and particle size analysis were chosen to illustrate: (1) the potential therapeutic efficacy of G872, a semi-synthetic sulfated polysaccharide, in stone prevention; and (2) the relative contribution of various urinary fractions ¿e.g., ultrafiltered urine (UFU), Tamm-Horsfall protein (THP), urinary polyanions precipitated with cetylpyridinium chloride (CPC), urinary macromolecular substances with different concentration ratios (UMS10,50,90 and UMS'10,50,90) and THP-free urine (THPFU)¿ to total urinary inhibitory activity. The results showed: (1) addition of G872 significantly enhances urinary inhibitory activity and negative zeta potential values; (2) re-addition of the CPC to UFU completely restores urinary inhibitory activity; and (3) artificial urines prepared by mixing UMS'10,50,90 from THPFU with UFU differed in inhibitory activity from that prepared by mixing UMS10,50,90 from a pooled normal urine with UFU. Based on these experimental results, the following speculations can be made: (1) normal human urines are considered to be a protective colloidal system; (2) urinary inhibitory activity originates mainly from CPC and/or UMS; (3) normal THP is a protective material to maintain urinary inhibitory activity; and (4) mutual interaction between urinary inhibitors may change the total urinary inhibitory activity.
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Affiliation(s)
- L C Cao
- Department of Urology, Erasmus University and Academic Hospital, Rotterdam, The Netherlands.
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de Bruijn WC, de Water R, Boevé ER, van Run PR, Vermaire PJ, van Miert PP, Romijn JC, Verkoelen CF, Cao LC, Schröder FH. Lectin-cytochemistry of experimental rat nephrolithiasis. Scanning Microsc 1998; 10:557-76. [PMID: 9813632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Lectin reactivity in epithelial apical cell coats of normal rat kidneys was compared to that from animals subjected to crystal inducing diets (CID). The aim was to see whether the absence of lectin reactivity in cell coats is related to intratubular calcium oxalate crystal retention. In normal rat kidneys, after a pre-embedding procedure, it was observed that at the ultrastructural level, reactivity was present but that the lectin specificity for the various parts of the nephron might have to be reconsidered. There was heterogeneity between the epithelial cells with respect to the presence of coat material in the tubular cell apices. Tubular epithelial cell apices from CID rats showed no obvious changes in lectin reactivity pattern. Lectin reactivity was present at the periphery of intratubular crystals but undetectable at true crystal attachment sites or reduced at cell apices in the vicinity of recently attached crystals or agglomerates. After a post-embedding reaction procedure, wheat-germ agglutinin (WGA)-lectin reactivity confirmed the presence of coat material in the cleft between cell apex and retained crystal at crystal-attachment sites. The WGA/Au-10 nm reaction products were also seen inside epithelial cells. WGA/Au-10 nm reaction products mark a crystal matrix component inside intratubular and retained crystals. A similar matrix was also marked by an alpha-osteopontin (alpha OPN/Au-10 nm) reaction product.
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Affiliation(s)
- W C de Bruijn
- AEM-unit, Clinical Pathology Institute, Erasmus University, Rotterdam, The Netherlands.
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de Water R, Boevé ER, van Miert PP, Vermaire CP, van Run PR, Cao LC, de Bruijn WC, Schröder FH. Pathological and immunocytochemical changes in chronic calcium oxalate nephrolithiasis in the rat. Scanning Microsc 1998; 10:577-87; discussion 587-90. [PMID: 9813633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
In the present study, we exposed rats to a crystal-inducing diet (CID) consisting of vitamin D3 and 0.5% ethylene glycol (EG), and we investigated histologically the kidney damage induced by the deposition of calcium oxalate (CaOx) crystals. After 28 days, 50% of the animals had renal CaOx crystals, of which 60% also had small papillary stones. Most crystals were present in the cortex. The occurrence of these crystals coincided with morphological and cytochemical changes: glomerular damage, tubular dilatation and necrosis, and an enlargement of the interstitium. The number of epithelial and interstitial cells positive for the proliferating cell nuclear antigen (PCNA) was increased. Tamm-Horsfall protein (THP) was not only demonstrable in the thick ascending limb of the loop of Henle (TAL), but also frequently in glomeruli, in the proximal tubular epithelium, and in the papilla. In the lumen of the tubular system, it was associated with urinary casts. Reflection contrast microscopy (RCM) showed that the crystals were coated with a thin layer of THP. In spite of the high urinary oxalate concentrations, the above described cellular changes were not observed in CID-fed rats without renal crystals. We conclude, therefore, that in the kidney, the retained CaOx crystals rather than the urinary oxalate ions are responsible for the observed morphological and immunocytochemical changes.
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Affiliation(s)
- R de Water
- Department of Urology, Faculty of Medicine, Erasmus University Rotterdam, The Netherlands
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14
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de Water R, Boevé ER, van Miert PP, Deng G, Cao LC, Stijnen T, de Bruijn WC, Schröder FH. Experimental nephrolithiasis in rats: the effect of ethylene glycol and vitamin D3 on the induction of renal calcium oxalate crystals. Scanning Microsc 1998; 10:591-601; discussion 601-3. [PMID: 9813634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Using ethylene glycol (EG) and vitamin D3 as crystal-inducing diet (CID) in rats, we investigated the effect of the dosage of EG on the generation of chronic calcium oxalate (CaOx) nephrolithiasis. We collected weekly 24 hour urines and measured herein the amount of oxalate, calcium, glycosaminoglycans (GAG's), creatinine, protein, alkaline phosphatase (AP), gamma-glutamyl transpeptidase (gamma-GT), and N-acetyl-beta-glucosaminidase (NAG). The potential of these urines to inhibit crystal growth and agglomeration was also evaluated. After four weeks, the kidneys were screened by histology and radiography for the presence of CaOx crystals and the amount of kidney-associated oxalate was biochemically measured. Using 0.5 vol.% EG, only a part of the rats showed CaOx deposition in the renal cortex and/or medulla, without obvious differences between Wistar and Sprague-Dawley (SD) rats. If a dietary EG concentration of 0.75, 1.0, or 1.5 vol.% was used, the amount of kidney-associated oxalate was proportionally higher and CaOx crystal formation was consistently found in all rats. Most crystals were encountered in the cortex, whereas in the medulla and the papillary region, crystals were only occasionally detected. From these data, we conclude that in the chronic rat model, based on EG and vitamin D3, a consistent deposition of CaOx crystals is obtained using a EG concentration of at least 0.75%.
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Affiliation(s)
- R de Water
- Department of Urology, Faculty of Medicine, Erasmus University Rotterdam, The Netherlands
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15
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de Bruijn WC, de Water R, van Run PR, Boevé ER, Kok DJ, Cao LC, Romijn HC, Verkoelen CF, Schröder FH. Ultrastructural osteopontin localization in papillary stones induced in rats. Eur Urol 1997; 32:360-7. [PMID: 9358227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES To detect in situ the precise osteopontin (OPN) localization in papillary stones. METHODS Immunocytochemical labelling procedures are applied to detect OPN localizations in crystalline material of renal papillary stones. The tissue-processing procedure for electron microscopy, which includes OsO4 postfixation, preserves both immunocytochemical OPN reactivity and cellular membrane contrast up to the ultrathin section. Reflection-contrast light microscopical images are correlated with high resolution transmission-electron microscopical observations from consecutive ultrathin epon sections. RESULTS Preserved crystalline material in interstitial and peripheral papillary stones is recognized as calcium oxalate monohydrate. After section incubation with markers conjugated to an antibody against OPN (alpha OPN) the crystals are converted into ghosts. In the ghosts, alpha OPN markers are present around microcrystals. The size of these microcrystals ranges from several nanometers to micrometers. It is observed (due to the OsO4-preserved membranes) that interstitial cells are separated from the stone surfaces by unidentified extracellular material, also present in the center as a stone matrix. CONCLUSION The microcrystal-growth inhibitor OPN is detected in situ in interstitial stones induced in the rat's papilla and at the surface of the papilla.
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Affiliation(s)
- W C de Bruijn
- AEM Unit, Erasmus University Rotterdam, The Netherlands.
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16
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Cao LC, Boevé ER, de Bruijn WC, Kok DJ, de Water R, Deng G, Schröder FH. Glycosaminoglycans and semisynthetic sulfated polysaccharides: an overview of their potential application in treatment of patients with urolithiasis. Urology 1997; 50:173-83. [PMID: 9255284 DOI: 10.1016/s0090-4295(97)00227-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- L C Cao
- Department of Urology, Erasmus University Rotterdam, The Netherlands
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17
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Cao LC, Deng G, Boevé ER, Romijn JC, de Bruijn WC, Verkoelen CF, Schröder FH. Does urinary oxalate interfere with the inhibitory role of glycosaminoglycans and semisynthetic sulfated polysaccharides in calcium oxalate crystallization? Eur Urol 1997; 31:485-92. [PMID: 9187912 DOI: 10.1159/000474511] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVES Previously it was shown that the polysaccharide G872 in vitro strongly inhibits calcium oxalate monohydrate crystallization processes. However, when rats on a stone-inducing diet of ethylene glycol plus vitamin D3 are given this polysaccharide, no changes in the urine capacity for crystallization inhibition were found. We investigated here how the inhibitory action of polysaccharides changes under high oxalate conditions, as they exist in the stone inducing diet. METHODS Calcium oxalate monohydrate (COM) crystals were incubated in a series of 0.05 M PBS buffers containing polysaccharides with increasing oxalate concentrations (0-0.4 mmol/l). The coated crystals were collected, washed and resuspended in an artificial urine. We then measured the zeta potential of the crystals, using a Coulter DELSA 440, and the initial rates for crystal growth and agglomeration, using the Coulter Multisizer II. RESULTS Addition of oxalate to the medium shifts the negative zeta potential distribution of COM crystals coated by polysaccharides in positive direction. Particle size analysis demonstrated that the initial rates of COM crystal growth and agglomeration responding to oxalate concentration changes (0.1-->0.4 mmol/l) in the presence of G872 (0.2 mg/l) are approximately 2.5 times faster than that in the absence of G872. CONCLUSIONS Oxalate interferes with the binding of polysaccharides to crystals. This can be envisioned to occur through changes in the crystal surface properties or by induction of functional and secondary structural changes of urinary macromolecular inhibitors such as GAGs, resulting in a decrease of their inhibitory activity against COM crystallization. Thus, in urine, a high oxalate may increase the rate of crystallization both by increasing the supersaturation and by decreasing the inhibitory potential of the urine.
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Affiliation(s)
- L C Cao
- Department of Urology, Erasmus University and Academic Hospital, Rotterdam, The Netherlands
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18
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Verkoelen CF, Romijn JC, Cao LC, Boevé ER, De Bruijn WC, Schröder FH. Crystal-cell interaction inhibition by polysaccharides. J Urol 1996; 155:749-52. [PMID: 8558718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
PURPOSE We studied the effect of polysaccharides on interactions between calcium oxalate monohydrate (COM) crystals and cultured renal cells. MATERIALS AND METHODS Monolayers of Madin-Darby canine kidney (MDCK) cells were incubated with radiolabeled crystals in the presence of various concentrations of natural glycosaminoglycans (GAGs) and semisynthetic polysaccharides (SSPs). RESULTS While most GAGs were found to have relatively little effect, SSPs (SP54, G871 and G872) were potent inhibitors of crystal-cell association. Pretreatment of crystals, but not of cells, was similarly effective, suggesting polysaccharide-induced modification of crystal surface properties. CONCLUSIONS This result further supports the idea that SSPs, and especially G872, are of potential interest for treatment of recurrent stone disease.
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Affiliation(s)
- C F Verkoelen
- Department of Urology, AEM-Unit, Erasmus University, Rotterdam, The Netherlands
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19
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Boevé ER, Cao LC, Deng G, De Bruijn WC, Schröder FH. Effect of two new polysaccharides on growth, agglomeration and zeta potential of calcium phosphate crystals. J Urol 1996; 155:368-73. [PMID: 7490888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
PURPOSE To study the effect of semisynthetic sulphated polysaccharides in the different calcium phosphate crystallization processes in vitro. MATERIALS AND METHODS Crystallization of hydroxyapatite (HAP) and brushite (DCPD) in the presence and absence of 2 new semisynthetic sulphated polysaccharides (G871, G872) were defined by a constant composition technique, particle size analysis and zeta potential measurement. RESULTS These polysaccharides demonstrated strong inhibitory effect on HAP and DCPD crystal growth and agglomeration. The increase of negative zeta potential values after addition of polysaccharides suggests the binding of these polysaccharides to HAP and DCPD crystals. CONCLUSION We conclude that both G871 and G872 could be of potential use for calcium phosphate urolithiasis prevention in addition to their use for calcium oxalate.
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Affiliation(s)
- E R Boevé
- Department of Urology, Erasmus University, Rotterdam, The Netherlands
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20
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Abstract
Many factors are presently known which determine the risk of calcium oxalate (CaOx) stone formation in the kidney, although the early events in the pathogenesis of this disease are still to be elucidated. One of these early events is the interaction of intraluminal crystals with the epithelial cells lining the renal tubules. In this study we determined the interaction of approximately 2 microns calcium oxalate monohydrate (COM) crystal with monolayers of Madin-Darby canine kidney (MDCK) cells grown on porous supports in a two-compartment culture system. Crystal-cell interaction studies were performed after the monolayers reached their highest level of gamma-glutamyltranspeptidase (gamma GT) enzyme activity, a marker for brush border development. Technical aspects were evaluated, such as the size and morphology of the crystals and the influence of incubation time, temperature and pH on crystal-cell interaction. Kinetic data demonstrated that an equilibrium between free and associated particles was reached within 30 minutes. Crystal-cell interaction was often associated with cell damage. However, evidence is provided that in an environment that was saturated with calcium oxalate, MDCK cells in an environment that was a certain amount of COM crystals without sustaining measurable injury. After initial attachment to the cell surface, crystals were taken up and subsequently eliminated again from the monolayers. The model system described in this paper provides a tool for detailed studies of processes that are involved in renal cellular handling of luminal COM crystals.
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Affiliation(s)
- C F Verkoelen
- Department of Urology, Erasmus University Rotterdam, The Netherlands
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21
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de Bruijn WC, Boevé ER, van Run PR, van Miert PP, de Water R, Romijn JC, Verkoelen CF, Cao LC, Schröder FH. Etiology of calcium oxalate nephrolithiasis in rats. I. Can this be a model for human stone formation? Scanning Microsc 1995; 9:103-14. [PMID: 8553009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Crystal retention is studied in a rat-model system as a possible mechanism for the etiology of human nephrolithiasis. A crystal-inducing diet (CID) of ethylene glycol plus NH4Cl in their drinking-water is offered to healthy rats to generate intratubular crystals. Subsequently, the fate of retained crystals is investigated by allowing the rats a tissue recovery/crystalluria phase for three, five and ten days, respectively, on normal drinking water. The process of exotubulosis is observed in cortex and medulla of aldehyde-fixed kidneys after three days recovery. After five days, crystals are predominantly seen there in the interstitium. After ten days, cortex and medulla are virtually free of crystals. However, in the papillary regions after five and ten days recovery, three types of calcium oxalate monohydrate (COM) crystals are present: (1) free in the calycine space, (2) sub-epithelially located surrounded by interstitial cells within, and (3) covered by macrophage-like cells, outside the original papillary surface. After a CID plus three days recovery, a further thirty-seven days extra oxalate challenge with solely 0.3 vol% ethylene glycol induced intratubular and interstitial oxalate crystals. In the papillary region, large sub-epithelial crystals are seen. However, no crystals are seen in kidneys from rats given solely (0.5 or 0.8 vol.%) ethylene glycol for thirty days. An oxalate re-challenge retards crystal removal.
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Affiliation(s)
- W C de Bruijn
- AEM-unit, Clin. Pathology Inst., Erasmus Univ. Rotterdam, The Netherlands
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22
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de Bruijn WC, Boevé ER, van Run PR, van Miert PP, de Water R, Romijn JC, Verkoelen CF, Cao LC, van 't Noordende JM, Schrder FH. Etiology of calcium oxalate nephrolithiasis in rats. II. The role of the papilla in stone formation. Scanning Microsc 1995; 9:115-24; discussion 124-5. [PMID: 8553010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In kidneys of healthy rats submitted to a crystal-inducing diet (CID) with ethylene glycol (EG) and NH4Cl, the fate of retained crystals in the papillar region is studied during a recovery period of one, five or ten days, as model system for human nephrolithiasis. Scanning electron microscopy (SEM) shows, at papillary tips bulging into the calycine space, crystal masses covered either by the epithelium or a thin fibrous veil, or by unidentified mobile cuboidal cells. After CID plus one or five days recovery, small sub-epithelial swellings are seen of large sub-epithelial crystals at or around the papillary tip. After CID plus ten days, massive sub-surface crystal-containing micrometer-sized stones are seen in which the presence of calcium is confirmed by X-ray microanalysis. The papillary tip of rats after a re-challenge with an oxalate load from 0.1 vol% EG for twelve or forty-two days shows minor lesions. But a re-challenge with 0.3 vol% EG for thirty-seven days induces large sub-epithelial papillary millimeter-sized stones. The Von Kossa section staining converts the crystals into a black precipitate, but large peri-tubular or peri-vascular calcium deposits are absent. A new hypothesis about the etiology of an inductive calcium oxalate monohydrate nephrolithiasis is formulated which differs from the one proposed by Randall based on his deductive human kidney studies.
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Affiliation(s)
- W C de Bruijn
- AEM-unit, Clin. Pathology Inst., Erasmus Univ. Rotterdam, The Netherlands
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23
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Boevé ER, Cao LC, De Bruijn WC, Robertson WG, Romijn JC, Schröder FH. Zeta potential distribution on calcium oxalate crystal and Tamm-Horsfall protein surface analyzed with Doppler electrophoretic light scattering. J Urol 1994; 152:531-6. [PMID: 8015107 DOI: 10.1016/s0022-5347(17)32788-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The zeta potential distribution (ZPD) and particle size of Tamm-Horsfall protein (THP) and of calcium oxalate monohydrate (COM) crystals were measured using a Doppler Electrophoretic Light Scattering Analysis Instrument. The studies showed differences in the ZPD pattern between THP derived from normal subjects (nTHP) and from stone patients (pTHP). Both nTHP and pTHP can shift the zeta potential of calcium oxalate crystals towards more negative values; nTHP is significantly more potent than pTHP. The zeta potential of both nTHP and pTHP becomes less negative with decreasing pH and with increasing calcium concentration or ionic strength. Tamm-Horsfall protein particle size measurements showed that nTHP particles are significantly smaller than pTHP particles. The size of both nTHP and pTHP increases with increasing calcium concentration or increasing ionic strength and with decreasing pH. The differences between nTHP and pTHP in surface charge and particle size may be based on differences in molecular structure and may cause functional differences in their ability to inhibit calcium oxalate crystal aggregation.
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Affiliation(s)
- E R Boevé
- Department of Urology, Erasmus University and Academic Hospital Dijkzigt, Rotterdam, The Netherlands
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24
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Boevé ER, Cao LC, Verkoelen CF, Romijn JC, de Bruijn WC, Schröder FH. Glycosaminoglycans and other sulphated polysaccharides in calculogenesis of urinary stones. World J Urol 1994; 12:43-8. [PMID: 8012415 DOI: 10.1007/bf00182050] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Naturally occurring glycosaminoglycans (GAGs) and other, semisynthetic, sulphated polysaccharides are thought to play an important role in urolithiasis. Processes involved in urinary stone formation are crystallization and crystal retention. Oxalate transport and renal tubular cell injury are determining factors in these processes. In this article experimental results concerning the possible mechanisms of action of GAGs and other sulphated polysaccharides are reviewed. GAGs are inhibitors of crystal growth and agglomeration and possibly also of nucleation. They can prevent crystal adherence, correct an abnormal oxalate flux and prevent renal tubular cell damage.
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Affiliation(s)
- E R Boevé
- Department of Urology, Academic Hospital Dijkzigt, The Netherlands
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25
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Verkoelen CF, Romijn JC, de Bruijn WC, Boevé ER, Cao LC, Schröder FH. Absence of a transcellular oxalate transport mechanism in LLC-PK1 and MDCK cells cultured on porous supports. Scanning Microsc 1993; 7:1031-1040. [PMID: 8146604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Transepithelial oxalate transport across polarized monolayers of LLC-PK1 cells, grown on collagen-coated microporous membranes in Transwell culture chambers, was studied in double-label experiments using [14C]-oxalate together with [3H]-D-mannitol as an extracellular marker. The [14C]-labeled glucose analog alpha-methyl-glucoside (alpha-MG) was used as functional marker for active proximal tubular sugar transport. Cellular uptake of oxalate and alpha-MG at both the apical and basolateral plasma membrane was determined. When added to the upper compartment, alpha-MG was actively taken up at the apical membrane, directed through the cells to the basolateral membrane and transported to the lower compartment, indicating functional epithelial sugar transport by LLC-PK1 cells. In LLC-PK1 cells, the uptake of alpha-MG at the apical membrane was approximately 50 times higher than that at the basolateral membrane. In contrast to this active transport of sugar, LLC-PK1 cells did not demonstrate oxalate uptake either at the apical or basolateral plasma membrane. The apical-to-basolateral (A- > B) flux of oxalate in LLC-PK1 cells was identical to the basolateral-to-apical (B- > A) oxalate flux in these cells. Moreover these flux characteristics were similar to those found for D-mannitol, indicating paracellular movement for both compounds. From these data, it is concluded that, under the experimental conditions used, LLC-PK1 cells do not exhibit a specific transcellular transport system for oxalate.
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Affiliation(s)
- C F Verkoelen
- Department of Urology, Erasmus University Rotterdam, The Netherlands
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26
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Cao LC, Boevé ER, de Bruijn WC, Robertson WG, Schröder FH. A review of new concepts in renal stone research. Scanning Microsc 1993; 7:1049-64; discussion 1064-5. [PMID: 8146606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Clinical and basic research in the field of urolithiasis has developed rapidly in recent years. Progress in extracorporeal shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PNL) has brought about a revolution in the surgical treatment of urolithiasis and research at the cellular and molecular level is now expanding. In spite of these advances, however, clinical treatment of urolithiasis remains far from satisfactory. Stone recurrence in many patients cannot be predicted and is beyond control of urologists mainly because the mechanisms of stone formation are still not fully understood. It is necessary to study the process of stone-formation more intensely at the cellular and molecular level, and to strengthen the links between basic and clinical research in the field. In this review, the processes involved in the formation of stones are compared with those involved in normal bio-mineralization and a model of urolithiasis is put forward based on modern systems science. Attention is concentrated on: (a) Directions of research based on physico-chemical theories of stone formation; (b) The role of renal tubular defects in urolithiasis; (c) The role of free radical reactions in stone formation; and (d) Macromolecular abnormalities and their correction.
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Affiliation(s)
- L C Cao
- Department of Urology, Erasmus University and Academic Hospital, Rotterdam, The Netherlands
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27
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De Bruijn WC, Ketelaars GA, Boevé ER, Sorber CW, Cao LC, Schröder FH. Electron energy-loss spectroscopical and image analysis of experimentally induced rat microliths. II. J Urol 1993; 149:900-5. [PMID: 8455271 DOI: 10.1016/s0022-5347(17)36255-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Following a microlith-inducing diet of ethylene glycol plus ammonium chloride, intraluminal and intracellular crystals are observed in aldehyde-fixed rat proximal and distal tubule cells by light and electron microscopy. Qualitative, in-situ analysis with electron-probe X-ray microanalysis (EPMA) of these intraluminal and intracellular crystals shows the presence of calcium, a trace of magnesium, some chlorine and the virtual absence of phosphorus and sulphur. Electron energy-loss spectroscopical element (EELS) analysis and electron-spectroscopic imaging (ESI) confirm, at both sites, the presence of calcium. Selected area electron diffraction (a) confirmed the crystallinity of both the intracellular and intraluminal crystals; (b) produced identical diffractograms from intracellular crystals in proximal tubule cells and deliberately internalized exogenous COM-crystals in cultured LLC-PK1 cells and (c) produced mean dhkl-values, identical to the dhkl-values from calcium oxalate monohydrate (14-771) in the ASTM index, from 4 different intracellular crystals in proximal-tubule cells.
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28
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Boevé ER, Ketelaars GA, Vermeij M, Cao LC, Schröder FH, De Bruijn WC. An ultrastructural study of experimentally induced microliths in rat proximal and distal tubules. J Urol 1993; 149:893-9. [PMID: 8455270 DOI: 10.1016/s0022-5347(17)36254-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Calcium oxalate stone formation was induced in rats by oral application of ethylene glycol and ammonium chloride for 4, 8 and 24 days. After each induction period, light-microscopically, birefringent crystals were seen in the tubular lumen and, intracellularly, in proximal and distal tubular cells. After a postfixation which partially removed the crystalline material crystal ghosts were seen by electron microscopy. In the lumen, crystal ghosts were observed ranging from single crystals to crystal agglomerates. The large intraluminal agglomerates were surrounded by epithelial cells and cellular debris. Both crystal types had an organic interior. In the cytoplasm of ultrastructurally changed proximal tubular cells, small (200 to 600 nm. in diameter) single crystal ghosts were present in the terminal web at the basis of the microvilli. Others were present in large vacuolar structures, with a fine granular matrix. After the prolonged microlith induction periods, such vacuolar structures were seen throughout the cell. The organic matrix of the crystal ghosts therein had acquired a more aggregated and complex structure.
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Affiliation(s)
- E R Boevé
- AEM-Unit, Erasmus University, Rotterdam, The Netherlands
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29
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Cao LC, Boevé ER, Schröder FH, Robertson WG, Ketelaars GA, de Bruijn WC. The effect of two new semi-synthetic glycosaminoglycans (G871, G872) on the zeta potential of calcium oxalate crystals and on growth and agglomeration. J Urol 1992; 147:1643-6. [PMID: 1593714 DOI: 10.1016/s0022-5347(17)37669-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effects of two new semisynthetic glycosaminoglycans (GAGs), G871 and G872, on the crystal growth and agglomeration of calcium oxalate monohydrate (COM) were studied in artificial urine in vitro. A constant composition crystallization system and a seeded crystal growth system were used to measure the rate of crystal growth and degree of agglomeration. The zeta potential on the crystal surface was measured using a Coulter DELSA 440 doppler electrophoretic light scattering analyzer. The previously reported GAG analogue, sodium pentosan polysulphate (SPP or SP54), was studied as a reference inhibitor of crystallization using the same systems. All three substances had a concentration-dependent effect on the zeta potential and on the rate of crystal growth and agglomeration of COM in artificial urine. G872 had a significantly greater effect than either G871 or SPP on all the measured parameters. It is suggested that semisynthetic GAGs, such as those reported in this paper may be of use in the prevention of the recurrence of calcium oxalate stones.
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Affiliation(s)
- L C Cao
- Department of Urology, Erasmus University, Rotterdam, The Netherlands
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30
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Sun CT, Cao LC, Han KH. Assessment of urine saturation and inhibitory index in patients with calcium oxalate kidney stone and normals. Chin Med J (Engl) 1987; 100:935-9. [PMID: 3133165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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31
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Han KH, Cao LC, Ying YL. [Determination of calcium, oxalate and inhibitory activity of the urine in patients with calcium nephrolithiasis]. Zhonghua Wai Ke Za Zhi 1986; 24:173-5, 190. [PMID: 3757655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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32
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Cai BJ, Cao LC, Guo YL. [The value of determination of urinary gamma-glutamyltranspeptidase in diagnosis of rejection after kidney transplantation (author's transl)]. Zhonghua Wai Ke Za Zhi 1981; 19:46-7. [PMID: 6118246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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