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Biomedical subjects

A Bohle

Publications and source records attributed to A Bohle.

At least 37 records · Page 2Linked to original sources
PubMed1992

The consequences for renal function of widening of the interstitium and changes in the tubular epithelium of the renal cortex and outer medulla in various renal diseases.

The following parameters were measured in 63 renal biopsy specimens, most of which exhibited mesangioproliferative glomerulonephritis: the relative area of the interstitium and the area of the capillaries in the cortex and outer stripe of the outer medulla, and the area of the epithelium of the proximal tubules and of the ascending limbs of Henle's loop. The percentage of hyalinized glomeruli was also determined. Investigation of correlations between these values and parameters of renal function revealed the following: 1) The serum creatinine concentration increases and the endogenous creatinine clearance decreases significantly as the interstitium of both the cortex and the outer stripe of the outer medulla increases in width. 2) The urine osmolality decreases significantly as the epithelial areas of the proximal tubules and ascending limbs of Henle's loop decrease, and as the serum creatinine concentration rises and the areas of the interstitium increase. 3) No significant correlation exists between the percentage of hyalinized glomeruli and the urine osmolality. 4) The total area of the intertubular capillaries in the cortex decreases significantly as the interstitium in this area increases in width and as the serum creatinine concentration increases. 5) Compensatory hypertrophy of individual nephrons, as proposed by Bricker's hypothesis, was found only where more than 90% of the glomeruli were hyalinized.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

The pathogenesis of chronic renal failure in diabetic nephropathy. Investigation of 488 cases of diabetic glomerulosclerosis.

Investigation of renal biopsy specimens from 488 patients with diabetic glomerulosclerosis (DGS) of varying severity revealed the following: 1) The severity of DGS increases with the duration of the diabetes. 2) As the severity of DGS increases, it is complicated with increasing frequency by exudative changes, which correspond in detail to hyperperfusion lesions described in the literature. 3) As the severity of DGS increases, the severity of arteriolosclerosis and the incidence of nephrotic syndrome increase significantly. 4) The 5- and 10-year renal survival rates are highest for those diabetic patients in whom the tubules and renal cortical interstitium are of normal appearance. These survival rates are diminished if any of the following are present at the time of biopsy: a) interstitial fibrosis; b) hyperperfusion lesions; c) nephrotic syndrome; d) elevation of the serum creatinine concentration to more than 1.3 mg%. 5) No significant correlation was found between renal survival rate and age, sex, or type of diabetes. 6) The inflammation of the renal interstitium seen in diabetes does not differ from that seen in chronic glomerulonephritis. Monocytes, macrophages, T lymphocytes, fibroblasts and fibrocytes play the major role in this inflammation. This inflammatory process is considered to represent not pyelonephritis, but rather an auto-immune process. In other words, it is proposed that the diabetic kidney fails not only as a result of non-specific glomerular lesions (hyperperfusion lesions) but also because of non-specific tubulointerstitial changes, whereas diabetic glomerulosclerosis alone does not lead to chronic renal failure.

Adult↗
PubMed1991

Mononuclear leukocytes, expression of HLA class II antigens and intercellular adhesion molecule 1 in focal segmental glomerulosclerosis.

Immunophenotyping of infiltrating glomerular and interstitial mononuclear leukocytes performed in renal tissues of 15 patients with focal segmental glomerulosclerosis (FSGS) was compared to 15 normal kidneys in order to investigate a possible role for cell-mediated immunity (CMI) in FSGS. In addition, distribution of HLA class II (-DQ, -DR, -DP and -DY) antigens and of the intercellular adhesion molecule 1 (ICAM-1) as well as the expression of well-defined renal antigens along the human nephron was analyzed. In comparison to normal kidneys, a reduction in HLA class II antigens of ICAM-1 and of renal antigens defined by the monoclonal antibodies TN8-TN10 was observed in sclerotic glomeruli. Furthermore, an increased number of T lymphocytes was found in glomeruli of FSGS with slight predominance of the CD8+ subset. Interstitial inflammation was present in all FSGS cases except 1 with T lymphocytes and monocytes/macrophages constituting the predominant infiltrating cell types. In contrast to the glomerular T cells, the number of interstitial CD4+ cells was greater than the number of CD8+ cells in almost all cases. As a sign of activation, most interstitial inflammatory cells carried HLA class II antigens and some of them also expressed ICAM-1. Proximal tubular epithelial cells often presented an abnormal expression of HLA-DQ and HLA-DP antigens associated with aberrant expression of ICAM-1 and TN8. The number of interstitial mononuclear leukocytes was correlated to serum creatinine levels at the time of renal biopsy. The present results provide further support for the involvement of CMI in the pathogenesis of FSGS.

Adult↗
PubMed1991

Hyperperfusion injury in IgA nephropathy.

The authors have found morphological alterations identical with hyperfiltration glomerular injury in the renal biopsies of 23 out of 100 patients with IgA nephropathy. In 15 of them the lesions were similar to the different stages of segmental glomerular hyalinosis and sclerosis with deposition of IgM and C3. At the time of renal biopsy, the serum creatinine of all except 8 patients was normal (maximally 170 mumol/1), only 13 had hypertension, and all except 2 were proteinuric. During the follow-up period (mean +/- 2Sd = 138 +/- 76 months) all of them became hypertensive. In 10 patients end-stage renal failure developed, and in another 10, serum creatinine also became elevated (range 124 - 504 mumol/1). On the basis of these data the development of focal segmental hyalinosis and sclerosis should be interpreted as a bad prognostic sign in IgA nephropathy.

Adult↗
PubMed1991

Hyperperfusion injury in IgA nephropathy.

The authors have found morphological alterations identical with hyperfiltration glomerular injury in the renal biopsies of 23 out of 100 patients with IgA nephropathy. In 15 of them the lesions were similar to the different stages of segmental glomerular hyalinosis and sclerosis with deposition of IgM and C3. At the time of renal biopsy, the serum creatinine of all except 8 patients was normal (maximally 170 mumol/1), only 13 had hypertension, and all except 2 were proteinuric. During the follow-up period (mean +/- 2Sd = 138 +/- 76 months) all of them became hypertensive. In 10 patients end-stage renal failure developed, and in another 10, serum creatinine also became elevated (range 124 - 504 mumol/1). On the basis of these data the development of focal segmental hyalinosis and sclerosis should be interpreted as a bad prognostic sign in IgA nephropathy.

Adult↗
PubMed1990

The consequences of tubulo-interstitial changes for renal function in glomerulopathies. A morphometric and cytological analysis.

Morphometric investigation of the structures of the cortex in kidneys exhibiting various types of glomerulopathy revealed the following: 1. In various types of glomerulonephritis, diabetic glomerulosclerosis, and glomerular amyloidosis there are significant correlations between the severity of fibrosis of the renal cortical interstitium and tubular atrophy resulting from chronic interstitial inflammation, and the serum creatinine concentration, creatinine clearance, inulin clearance and PAH clearance. 2. As illustrated with the example of membranoproliferative glomerulonephritis type I, if glomerulopathy alone is present, there is no elevation of the serum creatinine concentration, even if the glomerular inflammatory changes are severe; neither are severe renal amyloidosis that is confined to the glomeruli and severe isolated diabetic glomerulosclerosis associated with elevation of the serum creatinine concentration. 3. There is a significant negative correlation between the severity of interstitial fibrosis resulting from chronic inflammation and the total number and cross-sectional area of the intertubular capillaries; i.e., the total cross-sectional area and number of capillaries per unit area decrease as the fibrosis of the cortical interstitium increases. 4. Cases of glomerulonephritis in which there is accompanying fibrosis of the renal cortical interstitium have a significantly worse long-term prognosis than those in which there is only severe glomerulitis. 5. Obliteration of the post-glomerular capillaries leads to an increase in the cross-sectional area of the glomerular capillary convolution, the morphological equivalent of an increase in intraglomerular pressure. 6. The cause of the disease of the renal cortical interstitium that may accompany the various types of glomerulonephritis is not known. It is considered possible, as a working hypothesis, that this inflammation represents a T-cell stimulated autoimmune process in which fibroblast proliferation occurs, leading to an increase in numbers of fibrocytes in the renal cortical interstitium and thus to increased production of collagen.

Creatinine↗
PubMed1990

Association of glomerular and interstitial mononuclear leukocytes with different forms of glomerulonephritis.

Immunophenotyping of mononuclear leukocytes was performed in renal tissue obtained from 69 patients with different forms of glomerulonephritis (GN) and from ten donors' kidneys for transplantation used as controls. A panel of monoclonal antibodies was used in the immunoperoxidase technique on frozen sections to define B- and T-lymphocyte subpopulations, NK cells and monocytes/macrophages, as well as the expression of HLA class II antigens-DQ, -DR and -DP. Quantification of labelled leukocytes revealed a significant increase of CD4+ and CD8+ T-cells in glomeruli of rapidly progressive glomerulonephritis, membranoproliferative glomerulonephritis and even of focal gomerulosclerosis. The number of glomerular monocytes/macrophages was significantly increased only in rapidly progressive glomerulonephritis, whereas in membranoproliferative glomerulonephritis it was decreased. No differences to normal tissue were detected in glomeruli for all other types of inflammatory cells. Interstitial cells were mostly T-lymphocytes in all forms of glomerulonephritis. In all groups the CD4+/CD8+ ratio was somewhat greater than 1 and even about 2 in rapidly progressive glomerulonephritis. Only in particular case was this ratio inversed. High expression of HLA class II antigens was observed on interstitial mononuclear leukocytes, as a sign of their activation. The excess of HLA-DQ-positive cells over the sum of CD14+ and CD20+ cells provides evidence not only for presence of activated T-lymphocytes but perhaps also for accumulation of renal dendritic cells in the interstitium in glomerulonephritis associated with interstitial infiltration.

Antibodies, Monoclonal↗
PubMed1990

IgA nephritis: on the importance of morphological and clinical parameters in the long-term prognosis of 239 patients.

This study is concerned with the correlation between tubulointerstitial changes (interstitial fibrosis, acute renal failure, and interstitial fibrosis with acute renal failure), glomerular changes (focal and segmental lesions, hyperperfusion lesions), vascular changes, clinical data at the time of biopsy (serum creatinine concentration, creatinine clearance, hematuria, proteinuria, and hypertension) and first symptoms (hematuria, proteinuria and hypertension) and the kidney survival rate in 239 patients with IgA nephritis without nephrotic syndrome. The morphological and clinical parameters were subjected to multivariate analysis in order to examine their significance with regard to the prognosis. The interstitial fibrosis was proven to be the most important morphological parameter, and the most important clinical parameters were the serum creatinine concentration and the creatinine clearance.

Acute Kidney Injury↗
PubMed1990

Acute renal failure in man: new aspects concerning pathogenesis. A morphometric study.

The morphometric investigation of the proximal and distal tubules, the cortical interstitium, the intertubular capillaries, the renal corpuscles and the juxtaglomerular apparatuses (JGAs) in 56 cases in the oligoanuric, polyuric, and normuric phases of human acute renal failure (ARF), 6 cases of myeloma kidney with clinically confirmed ARF and 21 control kidneys revealed the following: (1) The main pathological change in human ARF is swelling of the epithelial cells of the proximal and distal tubules. Necrosis of these cells was observed in some cases but usually only as single cell necroses. (2) The interstitium of the cortex and of the outer stripe of the outer medulla is significantly widened in most cases of ARF. (3) In proximal tubules proximal to occluding casts (which were observed only in the plasmacytoma cases), the lumina are not widened but are narrower than normal, and the cross-sectional area of the epithelium is not greater but smaller than normal. (4) The JGAs were significantly larger in kidneys in the oligoanuric phase of ARF (with 1 exception) than in normal kidneys. In the normuric and polyuric phases they were slightly (not significantly) smaller than normal. In myeloma kidneys with occluding casts and/or diffuse interstitial fibrosis, the JGAs were significantly smaller than normal. From these findings it is concluded that: (1) The fall in glomerular filtration rate (GFR) in the postshock phase of ARF is not caused by nonselective back-diffusion of the primary urine through necrotic tubules or by compression of the lumina of the proximal and distal tubules by interstitial edema. A fall in GFR associated with occluding casts in the distal tubules is found only in the myeloma kidney and does not lead to widening of the proximal tubules but to tubular atrophy and narrowing of the lumen. (2) The casts seen in the lumina of the ascending limb of Henle's loop in some cases of ARF, which consist of hemoglobin, Tamm-Horsfall protein or desquamated blebs, do not occlude the lumen, since they are not associated with atrophy or luminal dilatation of the proximal tubules. (3) The JGAs with their secretory product renin-angiotensin II, together with adenosine, which is released in kidneys with ischemic or toxic damage, play a critical role in the pathogenesis of ARF. (4) In myeloma kidneys with ARF, in which the JGAs are markedly atrophic, the potentiated effect of adenosine that has been observed with a chronic absence of urine flow probably leads to a progressive, irreversible drop in GFR associated with tubular atrophy.

ADP-Ribosylation Factor 6↗
PubMed1990

Long-term prognosis of membranoproliferative glomerulonephritis type I. Significance of clinical and morphological parameters: an investigation of 220 cases.

We carried out a retrospective investigation in 220 patients to assess the influence of various parameters on the long-term course of membranoproliferative glomerulonephritis (MPGN) type I. 50 patients (23%) died during the follow-up period of 59 months on average, in another 57 (26%) end-stage renal failure developed. 54 patients (24%) suffered from chronic renal failure, stable renal function (creatinine below 1.3 mg/dl) was preserved in 59 patients (27%). 5 years after biopsy 49% of the patients had already died or needed regular dialysis treatment; after 10 years this proportion increased to 64%. Morphological findings: The outcome was--with the exception of focal crescent formations--not determined by the severity of glomerular changes; the survival rate, however, decreased significantly, if tubulointerstitial lesions were present as defined by acute renal failure, interstitial fibrosis or a combination of both. Clinical parameters: A progressive deterioration of renal function and an increasing number of renal deaths was noticed, when elevated serum creatinine levels at the time of biopsy and high blood pressure values during the follow-up period were observed. 26 patients died from hypertension, 18 of whom before reaching end-stage renal failure. Nephrotic syndrome and the degree of proteinuria as well as antiphlogistic and immunosuppressive treatment did not influence the prognosis of MPGN type I.

Adult↗
PubMed1990

Long-term prognosis of focal sclerosing glomerulonephritis. An analysis of 250 cases with particular regard to tubulointerstitial changes.

The following results were obtained in a long-term retrospective study including 250 patients with focal sclerosing glomerulonephritis: 1. The renal survival rate (RSR) was 90% at 5 years and 67% at 10 years, the average period of observation being 4.7 years. 2. Univariate analysis revealed that the following morphologic and clinical parameters are associated with an increased risk of terminal renal failure or death due to renal causes: a) Tubulointerstitial changes in the form of interstitial fibrosis, with or without acute renal failure; b) Advanced glomerular lesions; c) Advanced vascular alterations; d) Nephrotic syndrome present at the time of the biopsy; e) Elevated serum creatinine concentration at the time of the biopsy; f) Arterial hypertension at the time of the biopsy; g) Greater age at diagnosis; h) Male sex. 3. Multivariate survivorship analysis showed that tubulointerstitial changes and the presence of nephrotic syndrome at the time of biopsy are the only variables with significant independent predictive value for the outcome. Assessment of these factors thus allows the pathologist to make a relevant statement concerning the probable course and prognosis of the disease at the time of the diagnostic biopsy.

Adolescent↗
PubMed1989

Granular epithelioid cells of the kidneys in salmon adapted to fresh- and seawater.

The occurrence of granular epithelioid cells in the kidney arterial vessels was studied in one- and two-year-old Atlantic salmon during the physiological fresh- and seawater periods. The purpose of this study was to make long-term comparison on the morphology of the renin angiotensin system in the same fish species. One-year-old salmon living in freshwater had a statistically significant higher number of granular epithelioid cells (39.9 +/- 8.3/mm arterial vessel) than the two-year-old fish living in seawater (29.8 +/- 5.2/mm arterial vessel, P less than 0.00001). There was also a significant difference from month to month between the groups (P less than 0.05), but not within the groups (P greater than 0.07 freshwater, P less than 0.3 seawater). With the electron microscope the granules were found evenly distributed within the cytoplasm. They were of high electron density and lined by a single membrane. The granules were composed of a finely granular material. The recorded data on length and weight showed that all fish ate and developed normally. From our results and the available literature, we conclude that in primitive vertebrates, the renin angiotensin system is primarily involved in renal circulation, with vasoconstriction on the afferent side of the glomerulus.

Animals↗
PubMed1989

Renin-positive granulated Goormaghtigh cells. Immunohistochemical and electron-microscopic studies on biopsies from patients with pseudo-Bartter syndrome.

It is difficult to distinguish between Goormaghtigh cells (G-cells) and media cells of the glomerular arterioles at the border of the Goormaghtigh cell field. Consequently, it has been unclear whether renin-positive G-cells are normally present and also whether renin-producing cells are recruited from the pool of renin-negative G-cells upon stimulation of the renin-angiotensin system (RAS). In the present study, immunohistochemical and electron-microscopic experiments have been carried out on serially sectioned kidney biopsies from four patients with pseudo-Bartter syndrome. The results strongly suggest that with long-lasting stimulation of the RAS all renin-negative ("secretory resting") G-cells are ultimately converted into renin-producing granular cells.

Adult↗
PubMed1989

The pathogenesis of chronic renal failure.

The pathogenesis of terminal renal failure is discussed. The following are distinguished: 1. Renal failure occurring against a background of decompensated benign nephrosclerosis, primary and secondary malignant nephrosclerosis, and stenosis of the renal artery. 2. Renal failure caused by loss of glomeruli. It is pointed out that in most glomerulopathies, including diabetic glomerulopathy and renal amyloidosis, terminal renal failure only develops when accompanying disease of the postglomerular vessels leading to interstitial fibrosis impairs the outflow of blood from the glomerulus to such an extent that no more urine is produced. 3. Renal failure in disease of the tubules themselves. It is emphasized that acute renal failure only becomes chronic when interstitial fibrosis develops from the interstitial edema occurring in the early stage of the disease. 4. Renal failure occurring in primary diseases of the renal cortical interstitium. The chronic sclerosing renal diseases arising from acute interstitial nephritis are dealt with, as also are reflux nephropathy, incomplete obstructive nephropathy, analgesic nephropathy, and chronic interstitial rejection reactions in transplanted kidneys.

Diabetic Nephropathies↗
PubMed1989

Expression of HLA-DQ, -DR, and -DP antigens in normal kidney and glomerulonephritis.

Expression of the defined subtypes of HLA-class II antigens DQ, DR, DP, as well as of a putatively new HLA-class II determinant DY was evaluated with specific monoclonal antibodies on frozen sections of 15 normal kidneys, as well as of renal tissue of 65 patients with different forms of glomerulonephritis (GN). In normal kidney HLA-DR and/or -DY versus DQ or DP antigens were shown to be differentially expressed on subpopulations of glomerular and interstitial cells, as well as vascular endothelia. Normal proximal tubular epithelia lacked HLA-DQ and -DP antigens, but carried -DY and variably -DR products constitutively. In comparison, aberrant presence of HLA-DQ and/or -DP antigens was found on proximal tubular cells in the majority of patients with rapidly progressive (RPGN), membranoproliferative GN (MPGN), or focal glomerular sclerosis (FGS), but more rarely observed in other forms of proliferative or non-proliferative GN. In addition all cases with RPGN revealed reduction of HLA-DQ, -DR, -DP or -DY+ glomerular cells. Decline of HLA-DP and/or -DR+ glomerular cells was variably seen in mesangioproliferative glomerulonephritis (MesPGN) and MPGN, whereas in FGS HLA-DQ antigens appeared to be increased in glomeruli. HLA-DQ, -DR, -DY+ interstitial cellular infiltrates were present in RPGN, FGS and MPGN and only occasionally occurred in other forms of GN. Altered renal expression of HLA-class II antigens may indicate specific sites of immunologically-mediated kidney injuries in GN.

Antibodies, Monoclonal↗