Morphometric analysis of 80 renal biopsy specimens from patients with non-insulin-dependent diabetes mellitus, who had been classified into four groups by grade of proteinuria and renal function, revealed mitochondrial enlargement in the proximal tubules, with cellular hypertrophy as an initial morphologic change in the microalbuminuria. This was followed by a thickening of the proximal tubular basement membrane and an increased interstitial volume, causing persistent overt proteinuria. Glomerular nodular and sclerotic lesions and severe tubulointerstitial damage became evident in the advanced stages. As an initial cause of microalbuminuria, the mitochondrial abnormality disturbed adenosine triphosphate (ATP) metabolism in proximal tubules, reducing active transport and causing urinary excretion of low-molecular-weight protein.

Albuminuria↗

PubMedDate not supplied

Disruption of the blood-brain barrier caused by nonionic contrast medium used for abdominal angiography: CT demonstration.

We describe a case of disruption of the blood-brain barrier (BBB) by nonionic, low osmolality contrast medium after abdominal angiography. One plausible explanation of this event is that acute hypertension during angiography may have increased the BBB permeability, allowing the contrast medium to leak across it.

Aged↗

PubMedDate not supplied

MR angiography of renal vascular malformations.

OBJECTIVE: We wanted to determine whether three-dimensional phase contrast (3DPC) MR angiography is clinically useful in the diagnosis of renal vascular malformations. MATERIALS AND METHODS: Three-dimensional PC MR angiography was performed in 22 patients with gross hematuria and in 8 healthy volunteers. Small flip angles and 60 cm/s velocity encoding best demonstrated the normal intrarenal arteries with arteriovenous differentiation in the eight healthy volunteers. In the 22 patients with gross hematuria, intraarterial digital subtraction angiography demonstrated cirsoid-type malformations in 6 patients, aneurysmal-type malformations in 3 patients, and normal vascular anatomy in 13 patients. RESULTS: Magnetic resonance angiography detected all three aneurysmal-type malformations and four of the cirsoid-type malformations. Small cirsoid-type malformations were not detected in two patients. The moderate or large malformations were demonstrated as dilated and tortuous feeding arteries and high intensity renal veins with high flow velocity. We found no correlation between signal intensity in the suprarenal inferior vena cava and the presence of arteriovenous shunts. There were no false-positive cases. CONCLUSION: Sensitivity, specificity, and accuracy in this series were 78, 100, and 91%, respectively.

Adolescent↗

PubMedDate not supplied

MRI of the TMJ disc with intravenous administration of gadopentetate dimeglumine.

PURPOSE: The purpose of this study was to ascertain whether MR imaging with intravenous administration of gadopenetate dimeglumine (Gd-DTPA) is useful in the demonstration of the temporomandibular joint (TMJ) disc. METHOD: Sagittal T1-weighted MR images of 50 TMJs (25 patients) were obtained using a 0.5-T system both before and after intravenous injection of Gd-DTPA. The authors depicted the TMJ in which intravenous injection of Gd-DTPA improved visulization of the disc. RESULTS: Intravenous injection of Gd-DTPA increased intensity in the retrodiscal space, the pterygoid venous plexus, as well as joint effusion by diffused Gd-DTPA. The technique improved visualization of 10 (50%) of 20 normal discs and 20 (67%) of 30 anterior disc displacements in closed-mouth position, and also 23 (74%) of 31 normal discs and 12 (63%) of 19 anterior disc displacements in open-mouth position. There were 12 TMJs (24% of the 50 TMJs) in which equivocal findings became highly diagnostic. The incidence in marked contrast effect was higher in TMJs with severe internal derangement than in those with normal or mild internal derangement (p < 0.005). CONCLUSION: Using a 0.5-T MR imager, T1-weighted imaging with intravenous injection of Gd-DTPA showed more anatomic details than imaging without the contrast agent.

Adolescent↗

PubMedDate not supplied

Electron microscopic studies of ruptured arteries in hypertensive intracerebral hemorrhage.

Eleven freshly removed brains and 20 lenticulostriate arteries (collected at emergency surgery for intracerebral hemorrhage) were examined by electron microscopy in a search for the mechanism of arterial rupture in hypertensive intracerebral hemorrhage. Forty-six of 48 ruptured arteries examined showed severe arteriosclerosis including degenerative changes of the media at or near bifurcations. Atrophy and fragmentation of smooth muscle cells gave them a moth-eaten appearance. Material resembling basement membrane and cell debris was also present in the arterial walls. The above findings were restricted to the middle and distal portions of the perforating arteries. Rupture from a miliary aneurysm was observed in only 2 of the 48 specimens examined. These resembled saccular aneurysms, ultrastructurally. They seemingly formed at a cavity which we strongly felt may have been formed by complete or incomplete subclinical hemorrhages; reabsorption of the hemorrhage from the dissection resulted in the aneurysms seen. Degeneration of smooth muscle cells may be the result of prolonged tension or spasm of the arterial wall as a result of longstanding hypertension.

Adult↗

PubMedDate not supplied

Ultrastructural studies of cerebral arteries and collateral vessels in moyamoya disease.

Moyamoya disease was originally defined as a characteristic syndrome of recurrent headaches, occlusion of the distal internal carotid arteries and the foggy (moyamoya) clusters of collateral vessels at the base of the brain as demonstrated by cerebral angiography. The etiology is unknown and pathobiology is poorly understood. We examined the intracranial arteries in 3 patients to demonstrate characteristic changes and to obtain a better understanding of the basis mechanisms of the disease. Controls were obtained from 3 normotensive patients who died as a result of cancer. Occluded internal carotid arteries were characterized by severe thickening of the intima with a dense luminal array of smooth muscle cells, a deeper less cellular zone, pronounced tortuosity of the internal elastica and thinning of the media. Collateral vessels were arterial in structure and were affected by similar proliferative changes in the intima, thinning of the media, and contorted internal elastica. Stainable lipids were not part of the typical components. Severe contortion of the internal elastica, medial damage and intimal proliferation may result from recurrent and sustained spasticity of the cerebral arteries. The distal lenticulostriate arteries showed severe medial damage similar to what is termed as a moth-eaten change in hypertensive patients dying of massive cerebral hemorrhage.

Adult↗

PubMedDate not supplied

Ultrastructural morphometry of hypertensive medial damage in lenticulostriate and other arteries.

Characteristic medial damage occurs in the distal lenticulostriate arteries in patients with hypertensive cerebral hemorrhage. Medical changes were studied in the proximal and distal lenticulostriate arteries and cortical circumflex arterioles. Additionally, intramyocardial coronary, gastric submucosal and renal interlobular arterioles were examined in hypertensive patients. Hypertensive medial damage consisted of irregular atrophy and paucity of smooth muscle with accumulation of nonfatty debris and basement membranes. These changes were diffuse, extensive and not uniform, and were unrelated to atherosclerosis or bifurcation. By electron microscopic morphometry smooth muscle occupied 28% of the media in the distal lenticulostriate arteries of hypertensive patients as compared with 80% in controls. The proximal lenticulostriate and cortical branches in hypertensive patients showed values higher than 50%, as did the coronary, gastric and renal arterioles. Massive primary hemorrhages are prevalent in the area supplied by the distal lenticulostriate artery, 150-660 microns in diameter. Fibrinoid necrosis and microaneurysm occur in more peripheral arterioles, 70-200 microns. Thus, hypertensive medial damage with significant reduction of the smooth muscle area to less than 50% of the total media is viewed as an additional important factor which predisposes to sudden arterial rupture and massive cerebral hemorrhage.

Adult↗

PubMedDate not supplied

Ultrastructural changes of glomerular basement membrane in IgA nephritis: relationship to hematuria.

Ultrastructural changes in the glomerular basement membrane (GBM) of 415 samples from 344 patients with IgA nephritis, were examined for potential relationship to hematuria. The GBM showed various alteration: splitting, thinning, membranolysis with swelling of the lamina rara externa and interna, forming of small projections, and rupture. These lesions were present in 48% of IgA nephritis and in 16% of the controls. In the IgA nephritis group, the patients with hemispherical mesangial dense deposits had the highest rate (60%) of capillary wall abnormalities. Such lesions were more frequent in patients biopsied during severe hematuria (80%) than in those biopsied without hematuria (33%), (p less than 0.01). It is assumed that the ultrastructural abnormalities of GBM may contribute to the clinical evidence of severe hematuria.

Adolescent↗

PubMedDate not supplied

Nephropathy of nail-patella syndrome.

Ultrastructural renal lesions of a sporadic case of nail-patella syndrome are described. Although the patient, an 8-year-old Japanese boy, had no clinical renal syndrome, electron microscopy disclosed the presence of collagen fibrils and electron lucent areas within glomerular basement membrane. Comparative observation of glomeruli in sections stained by uranyl-acetate and lead-citrate and those by PTAH-uranyl revealed evidence of many collagen fibrils in mesangial matrix, as well as glomerular basement membrane. At the follow-up study 3 years after the biopsy, he still showed normal urinalysis and no renal dysfunction. Characteristic ultrastructure of glomerulus of this disease can be present even in cases without any apparent clinical renal involvement. It is concluded that the glomerular lesions in nail-patella syndrome may be caused by abnormal metabolic processes of collagen in glomeruli rather than entrapment of circulating collagen precursors.

Basement Membrane↗

PubMedDate not supplied

Combination radiotherapy of urinary bladder carcinoma with chemohyperthermia.

The combination therapy of urinary bladder cancer with radiation and hyperthermia with bleomycin was investigated. Immediately following daily external irradiation (40 Gy/4 weeks), patients were irrigated with a solution of warmed saline (intravesical temperature, 42-43 degrees C) containing 30 micrograms/ml bleomycin. Of a total of 56 patients, complete responses were observed in 25, and partial responses in 21. Among T2-T3 cases, an 84% response rate was noted in combination therapy, whereas a 56% response rate was observed after radiation alone (50-70 Gy). The side-effects of the combination therapy were limited to reversible bladder irritation, and bladder capacity could be maintained within normal limits. These results suggest that combination therapy represents an effective conservative therapy for the management of bladder cancer.

Administration, Intravesical↗

PubMedDate not supplied

p27 expression correlates with prognosis in patients with hypopharyngeal cancer.

BACKGROUND: Hypopharyngeal cancer is closely associated with smoking, drinking, and malnutrition. Recent findings reveal that carcinogenesis depends on genetic aberrations. MATERIALS AND METHODS: Eighty-one patients with hypopharyngeal cancer were analyzed for p53, CCND1, and p27, and 72 patients were analyzed for p21, immunohistochemically. RESULTS: p53 overexpression was found in 70%, CCND1 in 17%, p21 in 29%, and p27 in 32%. The low intensity of p27 expression correlated with poor prognosis, but the level of expression of p53, CCND1, and p21 did not. CONCLUSION: The immunohistochemical analysis of p27 provides a possible tool in determining the prognosis of patients with hypopharyngeal cancer.

Cell Cycle Proteins↗