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1.
Data Brief ; 52: 109856, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38146293

ABSTRACT

This data article provides temporally and spatially high-resolution datasets of the indoor velocity fields for cross-ventilation models of two-layered simplified buildings separated by a second floor at the middle height with an opening using wind-tunnel experiments. The datasets are based on the research article entitled "Quantifying natural cross-ventilation flow of a two-layered model used for terraced houses in tropical zones by particle image velocimetry" by Ali et al. [1]. Two cases are considered based on the positions of the inlet and outlet openings on each floor. The measurements were conducted using hot-wire anemometry (HWA) with 10,000 Hz and particle image velocimetry (PIV) with 1000 Hz for a sufficiently long period to determine reliable statistics of the mean, variances, and covariances. In addition, the article provides the instantaneous datasets of two velocity components determined by PIV for the cross-ventilation models. The datasets can be used for both computational fluid dynamics (CFD) validation and further investigation of turbulent flow nature of the multi-layer cross ventilation flow.

2.
AJNR Am J Neuroradiol ; 40(6): 1060-1066, 2019 06.
Article in English | MEDLINE | ID: mdl-31097427

ABSTRACT

BACKGROUND AND PURPOSE: The transmantle sign is a characteristic MR imaging finding often seen in focal cortical dysplasia type IIb. The transmantle sign is typically hyperintense on T2WI and FLAIR and hypointense on T1WI. However, in some cases, it shows T1 high signal. We evaluated the imaging and pathologic findings to identify the causes of the T1 high signal in the transmantle sign. MATERIALS AND METHODS: We retrospectively reviewed the preoperative imaging data of 141 consecutive patients with histologically proved focal cortical dysplasia. We selected 25 patients with focal cortical dysplasia with the transmantle sign and divided them into groups based on the pathologic focal cortical dysplasia subtype and T1 signal of the transmantle sign. We evaluated the clinical, radiologic, and pathologic findings, including the number of balloon cells and dysmorphic neurons and the severity of gliosis or calcifications and compared them among the groups. RESULTS: Nine of the 25 patients had a T1-high-signal transmantle sign; the other 16 patients did not. All 9 patients with a T1-high-signal transmantle sign were diagnosed as type IIb (group A). Of the 16 patients with no T1-high-signal transmantle sign, 13 were diagnosed as having type IIb (group B), and the other 3 patients, as type IIa (group C). The number of balloon cells was significantly higher in group A than in the other groups, but there were no differences regarding dysmorphic neurons, the severity of gliosis, or calcifications. CONCLUSIONS: Approximately 6% (9/141) of this patient series had a T1-high-signal transmantle sign, and all were type IIb. The signal may reflect a rich density of balloon cells. This finding could support the differentiation of subtypes, especially type IIb.


Subject(s)
Epilepsy/diagnostic imaging , Epilepsy/pathology , Magnetic Resonance Imaging/methods , Malformations of Cortical Development, Group I/diagnostic imaging , Malformations of Cortical Development, Group I/pathology , Neuroimaging/methods , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Image Interpretation, Computer-Assisted/methods , Male , Retrospective Studies , Young Adult
3.
Eur J Clin Nutr ; 64(8): 899-904, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20502470

ABSTRACT

BACKGROUND: The anthropometric measurement of mid-arm muscular area (MAMA) involves overestimation because of various assumptions, this overestimation being progressive with increasing adiposity. However, the effects of muscle atrophy and variation of the subcutaneous fat thickness have remained uncertain. OBJECTIVES: The validity of MAMA estimated by anthropometry was examined by comparing with MAMA measured by computed tomography (CT) in a nonobese population. The effects of muscle atrophy and variation of the subcutaneous fat thickness on the validity of MAMA were examined by new indices. SUBJECTS/METHODS: The relative MAMA was compared between the anthropometric and CT methods in 45 patients. New indices were introduced for assessing muscle deformity (muscle deformity index, MDI) and subcutaneous fat variation (SFVI). The effects of MDI, SFVI and age on the difference of MAMA between the anthropometric and CT methods were investigated. RESULTS: MDIs were positively correlated with age in males (r=0.47, P<0.05) and females (r=0.66, P<0.001). SFVI was positively correlated with age only in females (r=0.54, P<0.01). Even in these patients, the relative MAMA estimated by anthropometry was significantly associated with that measured by CT (r=0.85, P<0.0001 in males and r=0.90, P<0.0001 in females). A Bland-Altman plot indicated that the difference between both methods was relatively small, although increased adiposity might be a source of overestimation for anthropometric MAMA measurement. CONCLUSIONS: MAMA estimated by anthropometry was a reliable indicator of muscle mass in patients with muscle atrophy and varying thickness of subcutaneous fat in lean patients.


Subject(s)
Anthropometry , Arm/anatomy & histology , Muscle, Skeletal/anatomy & histology , Muscular Atrophy/pathology , Subcutaneous Fat/anatomy & histology , Age Factors , Aged , Aged, 80 and over , Arm/diagnostic imaging , Female , Humans , Male , Middle Aged , Muscle, Skeletal/diagnostic imaging , Muscular Atrophy/diagnostic imaging , Reference Values , Reproducibility of Results , Sex Factors , Subcutaneous Fat/diagnostic imaging , Thinness/diagnostic imaging , Thinness/pathology , Tomography, X-Ray Computed
4.
Clin Nephrol ; 57(3): 230-6, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11924755

ABSTRACT

BACKGROUND: Carpal tunnel syndrome (CTS) is one of the major problems of long-term hemodialysis (HD), but sometimes difficult to distinguish from uremic or diabetic neuropathy by clinical symptoms. PATIENTS AND METHODS: To evaluate the diagnosis of CTS more precisely, we examined the ultrasonographic alterations of the carpal tunnel and tendons of 90 wrists from 45 patients undergoing HD for more than 5 years. We measured the thickness of the palmar radiocarpal ligament (PRL), corresponding to the posterior wall of the carpal tunnel (CT), and the width of the CT, and compared those values with sensory (SCV), motor conduction velocity (MCV) of the median nerve and clinical symptoms. In addition, we longitudinally measured CT and PRL in the same patients for 5 years, and compared ultrasonographic changes and clinical parameters. RESULTS: A linear positive relationship was found between HD duration and PRL thickness (r = 0.43, p < 0.01) or CT width (r = 0.53, p < 0.01). CT diameter was negatively correlated with MCV (r = -0.30, p < 0.01) and SCV (r = -0.33, p < 0.04). PRL thickness was also inversely correlated with MCV (r = -0.44, p < 0.01) and SCV (r = -0.46, p < 0.01) of the median nerve, respectively. The wrists with clinical CTS and/or previous CTS surgery had significantly greater CT and PRL values compared to patients without CTS (CT: 6.1 0.2vs. 8.0+/-0.3 mm,p<0.01;PRL: 1.9+/-0.1 vs. 3.6 +/- 0.2 mm, p < 0.01). There was a significant increase in CT width from 6.2 +/- 0.2 to 7.1 +/- 0.2 mm (p < 0.01) and PRL thickness from 2.4 +/- 0.2 to 2.8 +/- 0.2 mm (p <0.01) during the 5-year observation, respectively. PRL thickness was constantly increased at the rate of 0.4 mm during the study. However, no significant association was found between the 5-year increases in CT and PRL distance and age, gender, the prevalence of diabetes, or laboratory parameters such as blood beta2-microglobulin, pentosidine and Kt/V(urea). CONCLUSION: Our data suggest that echographic evaluation of the wrist tissue thickness was useful to assess the progression of CTS. Serial measurements of the wrist by echography may be helpful to clarify the advance of subclinical CTS in patients receiving long-term HD.


Subject(s)
Carpal Tunnel Syndrome/diagnostic imaging , Ligaments, Articular/diagnostic imaging , Neural Conduction/physiology , Renal Dialysis/adverse effects , Wrist/diagnostic imaging , Adult , Aged , Aged, 80 and over , Carpal Tunnel Syndrome/etiology , Carpal Tunnel Syndrome/physiopathology , Cross-Sectional Studies , Disease Progression , Female , Humans , Longitudinal Studies , Male , Median Nerve/diagnostic imaging , Median Nerve/physiology , Middle Aged , Tendons/diagnostic imaging , Ultrasonography
5.
Ren Fail ; 23(5): 679-84, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11725914

ABSTRACT

Acute renal failure (ARF) is a well-documented but infrequent complication in patients treated with low-molecular weight dextran (LMWD). We herein report 3 cases of oliguric ARF following the administration of dextran-40. One case developed ARF totally after 1.200 g of LMWD administration. In contrast, two cases having increased serum creatinine developed oliguria despite the acceptable therapeutic doses (totally 450 and 650 g). Contrast media was also co-administered in these patients. Plasma exchange (PE), double filtration plasmapheresis (DFPP), or continuous hemodiafiltration (CHDF) but not hemodialysis (HD) reduced circulating dextran concentrations by 35-44% during a single session. All patients completely recovered from ARF by 14-32 days after the treatment. Our cases suggested that radiocontrast could predispose to the development of LMWD-induced ARF especially in patients having pre-existing renal dysfunction. In addition, PE, DFPP and CHDF afforded a beneficial effect for removing accumulated LMWD from the circulation.


Subject(s)
Acute Kidney Injury/chemically induced , Anticoagulants/adverse effects , Dextrans/adverse effects , Oliguria/chemically induced , Acute Kidney Injury/complications , Acute Kidney Injury/diagnosis , Aged , Anticoagulants/therapeutic use , Cerebral Infarction/drug therapy , Dextrans/therapeutic use , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Hearing Loss, Sudden/drug therapy , Humans , Kidney Function Tests , Male , Middle Aged , Oliguria/complications , Oliguria/diagnosis , Prognosis , Risk Assessment , Severity of Illness Index
6.
Am J Med Sci ; 322(1): 50-2, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11465248

ABSTRACT

We report our experience with a 62-year-old Japanese man with cholesterol crystal embolism after angiographic procedures performed because of intermittent claudication. In addition to progressive renal failure and nephrotic-range proteinuria, cutaneous ischemia, consisting of livedo reticularis in the lower limbs and digital necrosis at the tip of the right toe, and fundoscopic findings showing several white spots in the branches of retinal artery were also observed. Progressive renal failure and nephrotic-range proteinuria were halted just after treatment with simvastatin. Thus, simvastatin can exert a beneficial therapeutic effect on renal cholesterol embolism.


Subject(s)
Anticholesteremic Agents/therapeutic use , Embolism, Cholesterol/complications , Kidney Failure, Chronic/drug therapy , Nephrosis/complications , Proteinuria/complications , Simvastatin/therapeutic use , Anticholesteremic Agents/blood , Creatinine/blood , Disease Progression , Embolism, Cholesterol/blood , Humans , Kidney Failure, Chronic/blood , Kidney Failure, Chronic/etiology , Male , Middle Aged , Nephrosis/blood , Nephrosis/etiology , Proteinuria/blood , Proteinuria/etiology , Simvastatin/blood , Treatment Outcome
7.
Ren Fail ; 22(4): 511-5, 2000.
Article in English | MEDLINE | ID: mdl-10901188

ABSTRACT

We encountered a 53-year-old man associated with acute renal failure caused by Waldenström's macroglobulinemia and type I cryoglobulinemia. Treatment with prednisolone and cyclophosphamide induced a rapid recovery from acute renal failure. Renal histology revealed endocapillary proliferation and lobular formation with scattered subendothelial, amorphous and periodic acid-Schiff (PAS)-positive materials in the glomerular capillaries which were positive for IgM on immunofluorescence study. Although the exact mechanism for pathophysiology of acute renal failure remains unknown, treatment with prednisolone and cyclophosphamide could induce a rapid recovery from acute renal failure accompanied by Waldenström's macroglobulinemia and type I cryoglobulinemia.


Subject(s)
Acute Kidney Injury/etiology , Acute Kidney Injury/therapy , Cryoglobulinemia/complications , Waldenstrom Macroglobulinemia/complications , Acute Kidney Injury/diagnosis , Chlorambucil/therapeutic use , Combined Modality Therapy , Cryoglobulinemia/diagnosis , Cryoglobulinemia/drug therapy , Follow-Up Studies , Humans , Male , Middle Aged , Prednisolone/therapeutic use , Renal Dialysis , Waldenstrom Macroglobulinemia/diagnosis , Waldenstrom Macroglobulinemia/drug therapy
8.
Kidney Int ; 57(4): 1560-70, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10760091

ABSTRACT

BACKGROUND: We have previously reported that animals recovering from uranyl acetate (UA)-induced acute renal failure (ARF) were resistant to subsequent insult. Recent evidence suggests that apoptosis participates in tubular damage. We investigated the role of apoptosis in UA-induced ARF and attenuation of ARF in acquired resistance to UA in rats. METHODS: ARF was induced by an intravenous injection of UA (5 mg/kg) in rats. Rats of group 1 were injected with UA and followed for 28 days. Group 2 rats were injected with a second dose of UA (5 mg/kg) 14 days after the first injection and were followed for 14 days. All rats received an intraperitoneal injection of bromodeoxyuridine (BrdU) one hour before sacrifice. Using kidneys, histologic examination and immunohistochemical detection of proliferating cell nuclear antigen (PCNA), BrdU, Bcl-2, and Bax were performed. To detect apoptosis, electron microscopy, analysis of DNA fragmentation, and the TUNEL methods were adopted. RESULTS: UA increased the number of damaged renal tubules and serum creatinine, which peaked at 5 days in group 1, but both returned to baseline values by 14 days. Apoptosis was confirmed by electron microscopy and the "ladder" pattern of DNA fragments on gel electrophoresis. The number of apoptotic tubular cells evaluated by the TUNEL method showed two peaks at days 5 and 14 in group 1. The second peak of TUNEL-positive cells was preceded by an increased number of BrdU-positive nuclei, PCNA-positive nuclei, and total number of tubular epithelial cells. Renal damage after the second UA injection was markedly reduced. The peak number of apoptotic cells in group 2 was significantly less than that in group 1. CONCLUSIONS: Two peak levels of apoptotic cells occurred in UA-induced ARF. The first peak might play a role in UA-induced tubular damage, while the second one might represent the removal of excess regenerating cells during the recovery phase. Modulation of apoptotic cell death might be involved in the acquired resistance to rechallenge injury by UA.


Subject(s)
Acute Kidney Injury/chemically induced , Acute Kidney Injury/physiopathology , Apoptosis/physiology , Organometallic Compounds , Acute Kidney Injury/blood , Acute Kidney Injury/pathology , Animals , Cell Division , Creatinine/blood , Drug Resistance , Kidney Tubules/pathology , Male , Organometallic Compounds/pharmacology , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats , Rats, Sprague-Dawley , bcl-2-Associated X Protein
9.
Am J Nephrol ; 20(1): 27-31, 2000.
Article in English | MEDLINE | ID: mdl-10644864

ABSTRACT

In this study, the authors evaluated the cerebral atrophy in 56 chronic hemodialyzed patients, who did not have clinical episodes or radiologic findings of cerebrovascular diseases, and 42 controls. Using computed tomography (CT) images, brain atrophy index (BAI), the proportion of subarachnoidal plus ventricular space in the cranial cavity, and ventricular area index (VAI), percent area of ventricle in the brain, were calculated. CT of the brain demonstrated an age-dependent increase in BAI in both hemodialyzed patients and controls. BAI and VAI were greater in hemodialyzed patients than healthy controls and the difference was significant at ages under 60 years in BAI and at ages less than 50 years in VAI. The atrophy of the frontal parts of the brain in patients on hemodialysis for 10 years or more was significantly greater than in patients dialyzed for less than 10 years. There was a significant negative correlation between BAI or VAI and hematocrit. These findings indicate that renal failure or hemodialysis itself might cause cerebral atrophy, and that the cerebral atrophy is more prominent in patients on hemodialysis for a long duration and with low hematocrit.


Subject(s)
Brain/pathology , Cerebrovascular Disorders , Renal Dialysis , Adult , Aged , Aging/pathology , Anemia/pathology , Atrophy , Brain/diagnostic imaging , Case-Control Studies , Female , Humans , Kidney Failure, Chronic/pathology , Kidney Failure, Chronic/therapy , Male , Middle Aged , Time Factors , Tomography, X-Ray Computed
10.
Nephrol Dial Transplant ; 15(2): 191-9, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10648664

ABSTRACT

BACKGROUND: Transforming growth factor (TGF)-beta is a regulator of extracellular matrix accumulation. Both TGF-beta receptors, type I (TbetaRI) and type II (TbetaRII), may be required for signal transduction in the TGF-beta pathway. The aim of this study was to investigate the relationship between the TGF-beta pathways and glomerular basement membrane (GBM) accumulation in vivo. METHODS: We examined TbetaRI, II, and III protein expression on visceral glomerular epithelial cells (GEP) in relation to GBM alterations in passive Heymann nephritis (PHN), anti-GBM nephritis and anti-thymocyte serum (ATS) nephritis. Renal tissues were examined by pre-embedding immunoelectron microscopy 3, 7 and 14 days after induction of nephritis in rats. RESULTS: In normal control rats TbetaRI was not detected on GEP, TbetaRII expression was very occasionally found on GEP and TbetaRIII was seen in the cytoplasm of the GEP. TbetaRI, TbetaRII, and TbetaRIII were constitutively expressed on glomerular endothelial cells. By day 3 of anti-GBM nephritis and PHN, expression of TbetaRI, TbetaRII, and TbetaRIII was still similar to that of normal control rats, and GBM alterations in both models were not prominent except for deposit formation in PHN. From day 7 onwards, in both models, expression of TbetaRI and TbetaRII on GEP increased in association with GBM thickening. Expression of TbetaRIII in the cytoplasm of the GEP was increased, with occasional positive staining being seen on the urinary surface of the GEP from day 7 onwards. On the other hand, at day 3 of ATS nephritis, increased expression of TbetaRI and TbetaRII on GEP was noted, but from day 7 onwards, expression of TbetaR II on GEP dramatically decreased. Expression of TbetaRIII in the cytoplasm of the GEP also transiently increased at day 3. GBM thickening was not noted in ATS nephritis. CONCLUSIONS: The results suggest that persistent upregulation of expression of TbetaRI, TbetaRII and possibly TbetaRIII on GEP may contribute to GBM matrix accumulation in vivo.


Subject(s)
Basement Membrane/pathology , Kidney Glomerulus/metabolism , Kidney Glomerulus/pathology , Proteinuria/metabolism , Proteinuria/pathology , Receptors, Transforming Growth Factor beta/metabolism , Animals , Anti-Glomerular Basement Membrane Disease/pathology , Anti-Glomerular Basement Membrane Disease/urine , Epithelial Cells/metabolism , Epithelial Cells/pathology , Glomerulonephritis/immunology , Glomerulonephritis/pathology , Glomerulonephritis/urine , Immune Sera/immunology , Male , Microscopy, Immunoelectron , Protein Isoforms/metabolism , Rats , Rats, Wistar , Thymus Gland/cytology , Thymus Gland/immunology
11.
Ren Fail ; 21(5): 495-8, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10516994

ABSTRACT

Sudden cardiopulmonary arrest due to a defective respiratory reflex is observed in diabetic patients. Impaired ventilatory response in diabetic patients to acute hypoxia or hypercapnia induced by the inhalation of an artificial gas has been reported. Little is known regarding the respiratory compensatory ability for mild to moderate metabolic acidosis due to renal failure in insulin-dependent diabetic subjects. Arterial blood pH, HCO3-, PaCO2 and PaO2 were measured in 13 insulin-dependent diabetic subjects with advanced nephropathy and in 33 non-diabetic subjects with end-stage renal failure. The diabetic group consisted of six predialysis patients and seven on regular hemodialysis (HD) and the non-diabetic group, ten predialysis patients and 23 on HD. Differences between measured partial arterial pressure of carbon dioxide (PaCO2) and predicted PaCO2 determined from HCO3- were examined. PaCO2 was significantly higher in the diabetic than in non-diabetic group (40.0 +/- 7.4 versus 31.1 +/- 5.1 mmHg, p < 0.05 in predialysis, 42.0 +/- 6.4 versus 36.0 +/- 2.6 mmHg, p < 0.05 in HD), though plasma pH was essentially the same for either. Differences in measured PaCO2 and predicted PaCO2 were significantly larger in the diabetic group than in non-diabetic group. Ventilatory response to uremic acidosis may thus be considered impaired in subjects with advanced diabetic nephropathy.


Subject(s)
Acidosis/complications , Diabetes Mellitus, Type 1/complications , Diabetic Nephropathies/complications , Respiration Disorders/etiology , Acidosis/blood , Acidosis/therapy , Adult , Blood Gas Analysis , Chronic Disease , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/therapy , Diabetic Nephropathies/blood , Diabetic Nephropathies/therapy , Female , Humans , Kidney Failure, Chronic/blood , Kidney Failure, Chronic/etiology , Kidney Failure, Chronic/therapy , Male , Renal Dialysis , Respiration Disorders/blood , Uremia/blood , Uremia/complications , Uremia/therapy
13.
J Am Soc Nephrol ; 9(12): 2253-61, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9848779

ABSTRACT

Protein and mRNA expression of transforming growth factor-beta (TGF-beta) receptor type I (TbetaRI), type II (TbetaRII), and type III (TbetaRIII) were studied in serial sections of kidney samples obtained from patients with glomerulonephritis. In minimal change disease, weak expression of TbetaRI and TbetaRII was observed mainly in glomerular endothelial cells, peritubular capillaries, and interstitial arteriolar endothelial cells, whereas TbetaRIII expression was found mainly in the interstitium. Expression of all three TGF-beta receptors (TbetaR) was increased remarkably in glomerular and Bowman's capsular cells comprising the tuft adhesions to Bowman's capsules in glomerulonephritis with increased matrix accumulation, including IgA nephropathy, lupus nephritis, focal and segmental glomerulosclerosis, myeloperoxidase-antineutrophil cytoplasmic antibody-associated crescentic glomerulonephritis, and membranoproliferative glomerulonephritis. Increased expression of the three TbetaR was also seen in glomerular epithelial cells in the vicinity of glomerulosclerotic lesions, in crescent cells, and in some tubules and infiltrative mononuclear cells found in the periglomerular and tubulointerstitial lesions with increased matrix deposition. In contrast, no remarkable TbetaRII expression was noted in mesangial proliferative lesions in IgA nephropathy, lupus nephritis, and membranoproliferative glomerulonephritis. These data suggest that distinctive modulation of TbetaR expression may be involved in the development of adhesive, sclerotic, and proliferative renal lesions in human glomerulonephritis.


Subject(s)
Activin Receptors, Type I , Glomerulonephritis/metabolism , Protein Isoforms/biosynthesis , Protein Serine-Threonine Kinases/biosynthesis , Proteoglycans/biosynthesis , Receptors, Transforming Growth Factor beta/biosynthesis , Gene Expression Regulation , Glomerulonephritis/classification , Glomerulonephritis/genetics , Glomerulonephritis/pathology , Glomerulonephritis, Membranoproliferative/metabolism , Glomerulonephritis, Membranoproliferative/pathology , Glomerulonephritis, Membranous/metabolism , Glomerulonephritis, Membranous/pathology , Glomerulosclerosis, Focal Segmental/metabolism , Glomerulosclerosis, Focal Segmental/pathology , Humans , In Situ Hybridization , Kidney Glomerulus/metabolism , Kidney Glomerulus/ultrastructure , Kidney Tubules/metabolism , Kidney Tubules/ultrastructure , Lupus Nephritis/metabolism , Lupus Nephritis/pathology , Microscopy, Immunoelectron , Nephrosis, Lipoid/metabolism , Nephrosis, Lipoid/pathology , Protein Isoforms/genetics , Protein Serine-Threonine Kinases/genetics , Proteoglycans/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Receptor, Transforming Growth Factor-beta Type I , Receptor, Transforming Growth Factor-beta Type II , Receptors, Transforming Growth Factor beta/genetics
17.
Am J Kidney Dis ; 28(6): 878-87, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8957040

ABSTRACT

Low-protein diets slow the progression of some renal diseases. We recently found that dietary restriction of L-arginine markedly ameliorates disease in antithymocyte serum-induced glomerulonephritis in the rat, suggesting that L-arginine may play a key role in the beneficial effects of low-protein diets. L-arginine is metabolized by nitric oxide synthases to nitric oxide and L-citrulline or by arginase to urea and L-ornithine. L-ornithine is a precursor for polyamines, which are required for cell proliferation and for proline, an essential component of collagen. In a time course of disease, we found that inducible nitric oxide synthase gene expression and nitric oxide production were increased very early. Arginase activity was significantly increased until 5 days of disease. Ornithine decarboxylase, the rate-limiting step for polyamine synthesis, was increased at 3 days coincident with the onset of cell proliferation. Gene expression of ornithine aminotransferase, a proline synthetic enzyme, was increased from day 1, paralleling increased collagen synthesis. Thus, the three pathways of L-arginine metabolism are upregulated in a manner consistent with their possible roles in the cell lysis, cell proliferation, and collagen deposition, which characterize this model of glomerulonephritis.


Subject(s)
Arginine/metabolism , Glomerulonephritis/metabolism , Animals , Antilymphocyte Serum/immunology , Arginase/metabolism , Cell Division , Cells, Cultured , Collagen/metabolism , Gene Expression , Glomerulonephritis/immunology , Glomerulonephritis/pathology , Immunohistochemistry , Kidney Glomerulus/enzymology , Kidney Glomerulus/pathology , Male , Nitric Oxide/metabolism , Ornithine Decarboxylase/metabolism , Ornithine-Oxo-Acid Transaminase/genetics , Ornithine-Oxo-Acid Transaminase/metabolism , Proline/metabolism , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley
18.
Am J Physiol ; 271(4 Pt 2): F846-53, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8898014

ABSTRACT

Contralateral uninephrectomy attenuates unilateral ischemic renal injury functionally and morphologically. In this study we investigated the effects of uninephrectomy on apoptotic renal cell death and tubular regeneration in ischemic acute renal failure (ARF) in rats. Unilateral ischemic injury was provoked by a 60-min left renal artery occlusion in right-nephrectomized (Nx) and sham-nephrectomized (sham-Nx) rats. Uninephrectomy attenuated tubular damage 48 h following the renal ischemia Apoptotic cells were found in renal tissue as early as 3 h after reperfusion and increased in number by 12 h. The "ladder" pattern of DNA fragments on agarose gel electrophoresis was also apparent in ischemic kidney. Uninephrectomy reduced apoptotic cells and DNA fragmentation. The expression of proliferating cell nuclear antigen (PCNA) could be seen 24 h after reperfusion and progressively increased thereafter PCNA expression in ischemic kidney was greater in Nx than sham-Nx rats at 24 h after renal reperfusion. These data suggest that uninephrectomy reduces apoptotic cells and DNA fragmentation and enhances PCNA expression. The reduced apoptotic cell death and enhanced cell regeneration may be importantly involved in the uninephrectomy-induced attenuation of ischemic acute renal failure in rats.


Subject(s)
Acute Kidney Injury/pathology , Apoptosis , Ischemia/pathology , Kidney Tubules/pathology , Nephrectomy , Renal Circulation , Animals , Cell Division , DNA Fragmentation , Ischemia/genetics , Kidney Tubules/physiopathology , Male , Proliferating Cell Nuclear Antigen/metabolism , Rats , Rats, Sprague-Dawley , Regeneration
19.
Clin Nephrol ; 44(4): 231-7, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8575122

ABSTRACT

The carpal tunnel syndrome (CTS) is the most frequent clinical symptom of dialysis-related amyloidosis. We examined CTS by ultrasound imaging and correlation between CTS and bone amyloidosis was sought. One hundred and forty-two wrists of 71 hemodialysis (HD) patients and 28 of 14 normal volunteers (group 1) were studied. Patients on HD were divided into 4 groups based on HD duration: Group 2, less than 5 years; group 3, 5-10 years; group 4, 10-15 years; and group 5, more than 15 years. The frequency of CTS increased gradually with HD duration: 0% in group 2, 35.3% in group 3, 36.4% in group 4 and 74.1% in group 5. The thickness of the palmar radiocarpal ligament (PRL), corresponding to the posterior wall of the carpal tunnel was significantly greater in groups 4 (p < 0.05), and 5 (p < 0.05) than in group 1 (2.25 +/- 1.30 and 3.11 +/- 1.02 in group 4 and 5 vs 1.15 +/- 0.34 mm in group 1); and the width of the carpal tunnel (CT) was significantly larger in group 5 than in group 1 (6.92 +/- 1.78 in group 5 vs 5.53 +/- 1.48 mm in group 1, p < 0.05). Wrists operated on for CTS had significantly increased PRL and CT compared to the control group and patients without CTS. Patients with CTS had wider PRL than the control and HD patients without CTS. Cystic radiolucent lesions (CRL) of carpal bones characteristic of bone amyloidosis were noted in 15 of 71 HD patients. The thickness of PRL and width of CT in HD patients with CRL exceeded those in patients without CRL. These data indicated that ultrasonographic findings of wrists were closely correlated with the degree of CTS and CRL. The usefulness of ultrasonographic evaluation of PRL thickness and CT width in the evaluation of dialysis-related amyloidosis should be evaluated.


Subject(s)
Amyloidosis/diagnostic imaging , Carpal Tunnel Syndrome/diagnostic imaging , Renal Dialysis/adverse effects , Amyloidosis/etiology , Amyloidosis/pathology , Carpal Tunnel Syndrome/etiology , Carpal Tunnel Syndrome/pathology , Female , Humans , Male , Middle Aged , Ultrasonography , Wrist/diagnostic imaging
20.
Am J Kidney Dis ; 25(5): 807-9, 1995 May.
Article in English | MEDLINE | ID: mdl-7747737

ABSTRACT

A 66-year-old woman with chronic renal failure who had undergone hemodialysis for 15 years developed severe dilatation of the ascending and transverse colon. She had received right carpal tunnel release 5 years before this episode. The follow-up study of upper gastrointestinal series disclosed marked dilatation of the ascending and transverse colon with the retention of gastrografin persisted for 5 days, whereas colonic fiberscope showed no obstructive lesion. Pathologic study of biopsy specimens obtained from the colon demonstrated amyloid deposition. Avidin-biotin peroxidase complex method showed that these deposits strongly reacted with the antibody to human beta 2-microglobulin, but did not react with AA, lambda, and kappa antibodies. This case suggests that dialysis-related amyloidosis can cause intestinal pseudo-obstruction.


Subject(s)
Amyloidosis/etiology , Colonic Diseases/etiology , Renal Dialysis/adverse effects , Aged , Amyloidosis/complications , Carpal Tunnel Syndrome/etiology , Colonic Diseases/diagnostic imaging , Dilatation, Pathologic/diagnostic imaging , Dilatation, Pathologic/etiology , Female , Humans , Radiography
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