Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nephroblastomas are induced in rats with N-Methyl-N-Nitroso-Urea, and selective renal artery occlusion is performed. This procedure has the same effect like occlusion by embolization. The effect of renal artery occlusion on the growth rate of nephroblastmas is controlled by angiography and gross and microscopic examinations up to 70 days following ischemia, the results are compared with a group of untreated nephroblastoma rats. There is a marked reduction of tumor size and a decrease in tumor proliferation. There is an immediate tumor cell death induced by acute and complete ischemia. Collateral blood vessels cause residual arterial blood supply of tumor parenchyma. There seems to be a correlation between collateral blood delivery and tumor size. Even 70 days after permanent ischemia there are areas of obviously absolute normal tumor cells. The conclusion of this experimental study demonstrated that growth rate of tumors can be reduced by ischemia although potentially malignancy still remains. Clinical embolization therapy is justified only in nonoperable patients with hypernephroma and with massive hematuria.
 ...
PMID:[The influence of renal artery occlusion on tumor growth of experimental nephroblastomas (author's transl)]. 20 93

From 1985 to June 1989 diagnostic tumour resections have been performed on 37 kidney tumours with unknown dignity following the preoperative imaging techniques. The kidney tumours were completely excised with about 1 cm of adjacent parenchyma outside the pseudocapsule during temporary ischemia. The tumours and biopsies from the resection margins were sent to quick frozen section. In case of benign histology or low grade clear cell carcinomas with exophytic growth and a size of less than 5 cm in diameter the operation was finished without removing of the kidney. In 21 patients with benign and 11/16 with malignant disease the kidneys could be preserved. In 5/16 patients the kidneys were removed after tumour resection and result of the quick frozen section. In our opinion the diagnostic kidney tumour resection in cases of kidney tumours with unknown dignity should be preferred to fine needle biopsies combining diagnostic and therapeutic proceeding in selected cases. On the other hand tumour resections without nephrectomy in patients with renal cell carcinoma and normal contralateral kidney should be done only in low grade tumours of small size.
 ...
PMID:[Diagnostic tumor resection in kidney tumors of unclear quality]. 226 32

Renal cell carcinoma is an unpredictable tumor that often has already metastasized when first seen. It can affect many organs before the primary tumor is found. We describe a unique example of renal cell carcinoma first seen as repeated episodes of small-bowel infarction caused by tumor emboli from a metastasis in the left ventricle. Although intestinal ischemia caused by emboli is not uncommon, intestinal ischemia resulting from metastatic tumor emboli occurs in only a small percentage of cases. We suggest that surgeons include the possibility of tumor emboli in the differential diagnosis for mesenteric or peripheral ischemia that cannot be attributed to more common causes.
 ...
PMID:Embolic mesenteric infarction: a unique initial manifestation of renal cell carcinoma. 268 76

Recombinant gamma interferon (r-GIFN) demonstrates in vitro and in vivo characteristics that contrast with those of alpha and beta interferons. It has relatively weak antiviral properties, yet relatively potent immunomodulatory effects. A phase I trial was performed with r-GIFN (specific activity 2.6 X 10(6) IU/mg protein), administered as a continuous intravenous (IV) infusion over 24 hours for five days (Cl X 5) and repeated every 28 days. This schedule was chosen based on the short half-life of r-GIFN in animal systems and the in vitro augmentation of biologic effects with continuous exposure to interferons. Twenty-one patients with refractory solid tumors received 46 evaluable courses of therapy. The dose-limiting toxicities included fever, flu-like symptoms, cardiovascular toxicity, and neurotoxicity. The cardiovascular toxicity included hypotension and one episode of cardiac ischemia with chest pain. Neurotoxicity consisted of lethargy and confusion. These toxicities were reversible, and although dose-limiting, occurred sporadically throughout all dosage levels. Mild to moderately severe non-dose-limiting toxicities included nausea and vomiting, leukopenia, and liver function abnormalities. Other infrequent toxicities included hypocalcemia, diarrhea, constipation, and alopecia. The maximally tolerated dose of r-GIFN on this schedule is 0.5 X 10(6) IU/m2/d. Partial responses were seen in one patient with metastatic melanoma and in one patient with renal cell carcinoma. Toxicity and antitumor activity were seen at doses where interferon serum levels could not be detected by radioimmunoassay. In addition, the toxicity and antitumor activity seen were at much lower doses than previously described for shorter infusion schedules of other recombinant gamma interferon preparations. Differences in biologic activity of interferon preparations and/or differences in scheduling may account for this variability. Although this study defines a recommended phase II dose of r-GIFN based on the maximally tolerated dose, the optimal therapeutic index may exist at a lower dosage level.
 ...
PMID:A phase I clinical trial of recombinant DNA gamma interferon. 310 84

A unique form of acquired renal cystic disease occurs commonly in the end stage kidneys of patients with chronic renal failure. Recent experience with 3 cases of acquired renal cystic disease has made us aware that the condition has significant urological implications. The pathogenesis of this disease is unknown but may be related to tubular obstruction, ischemia or the accumulation of toxic products. The diagnosis of acquired renal cystic disease is established by either ultrasound or computerized tomography, both of which demonstrate bilateral multiple small cysts scattered throughout the cortex and medulla of the contracted end stage kidney. Acquired renal cystic disease usually is asymptomatic but may be associated with either hemorrhage or neoplasia. Autopsy studies have revealed renal tumors in up to 45 per cent of the patients with acquired renal cystic disease. These tumors usually are small but our case 3 was a renal cell carcinoma that measured 4 cm. in diameter. Also, there have been other recent reports of large tumors and deaths of metastatic renal carcinoma in patients with acquired renal cystic disease. Patients with chronic renal failure should undergo periodic examination of the native kidneys by either ultrasound or computerized tomography. It may be difficult to distinguish benign from malignant lesions radiologically, and nephrectomy may be indicated when the diagnosis is uncertain.
 ...
PMID:Acquired renal cystic disease in the end stage kidney: urological implications. 647 Nov 94

In a 71-year-old female with severe hypertension, bilateral renal artery stenosis and renal adenocarcinoma, a renal vein renin study revealed suppressed renin secretion from the kidney with carcinoma and contralateral ischemia. The hypertension was not cured by surgical removal of the kidney with carcinoma. Hypertension is frequently noted in patients with renal adenocarcinoma (28% of 603 patients reported in the literature). This type of hypertension is frequently improved after removal of the tumor (83% of 36 surgically treated patients). In certain patients the pathogenesis of hypertension associated with renal adenocarcinoma may be related to renin secretion from the tumor or to renin activation due to regional ischemia caused by vascular compression. In other patients the renin-angiotensin system does not appear to play a pathogenic role in the development of hypertension associated with renal adenocarcinoma.
 ...
PMID:[Arterial hypertension: adenocarcinoma of the kidney or bilateral renal artery stenosis$]. 672 21

Different techniques and materials for preoperative embolization of renal carcinoma have been assessed in 26 cases. The different methods used and compared were gelfoam fragments (10 cases), cyanoacrylate (4 cases), Gianturco stainless steel coil (3 cases) and the combination of gelfoam and the Gianturco device (9 cases). The method of choice appears to be the combination of gelfoam and the Gianturco device which allows excellent peripheral ischemia with complete occlusion of the main arterial trunks. Embolization is particularly useful in invading and hypervascularized renal tumors supplied by collateral blood vessels.
 ...
PMID:Preoperative embolization of renal tumors--comparison of different methods. 737 61

The technical results of 259 nephron sparing operations for renal cell carcinoma or renal oncocytoma were reviewed. Local or renal related complications occurred after 78 procedures (30.1%). The incidence of complications was less for operations performed after 1988 (22% versus 37%, p = 0.009) and for incidentally detected versus suspected tumors (p = 0.009). The most common complications were urinary fistula formation (45 operations) and acute renal failure (33). Significant predisposing factors for urinary fistula formation included central tumor location (p = 0.001), tumor size greater than 4 cm. (p = 0.001), the need for major reconstruction of the collecting system (p = 0.001) and ex vivo surgery (p = 0.001). Only 1 urinary fistula required open operative repair, while the remainder resolved either spontaneously (30) or with endoscopic management (14). Significant predisposing factors for acute renal failure included a solitary kidney (p = 0.001), tumor size greater than 7 cm. (p = 0.008), greater than 50% parenchymal excision (p = 0.001), greater than 60 minutes of ischemia time (p = 0.035) and ex vivo surgery (p = 0.001). Acute renal failure resolved in 28 patients, of whom 9 required temporary dialysis, while 5 required permanent dialysis. Overall, 8 complications (3.1%) required repeat open surgery for treatment while all other complications resolved with noninterventive or endourological management. Surgical complications contributed to an adverse clinical outcome in only 7 patients (2.9%). Nephron sparing surgery can be performed safely with preservation of renal function in most patients with renal tumors.
 ...
PMID:Complications of nephron sparing surgery for renal tumors. 815 54

Between 1975 and 1991, 142 patients with renal cell carcinoma and 10 with oncocytoma underwent a total of 164 kidney preserving operations. The indication for surgery was imperative (group 1, 47 patients) among those with a solitary kidney (9), renal insufficiency (17) or bilateral tumors (21). Of the patients with small or peripheral tumors and a healthy contralateral kidney 105 were selected for elective surgery (group 2). Most procedures were done either without ischemia (24%) or with warm ischemia (69%). In some patients from the imperative indication group hypothermia was achieved by in situ perfusion (5%) or ex vivo work bench surgery and autotransplantation (2%). Complication rates were 15% for group 1 and 9.5% for group 2. In group 1, 3 patients died of cancer, 5 lived with metastases and 2 had local tumor recurrence. No patient in group 2 had recurrences or metastases. The tumor-specific survival rate of patients with kidney preservation for renal cell carcinoma was comparable to that of a control group undergoing radical nephrectomy. Due to the high reliability and efficacy, kidney preserving surgery for renal cell carcinoma should be done more often, even in patients with a normally functioning contralateral kidney.
 ...
PMID:Kidney preserving surgery in renal cell tumors: indications, techniques and results in 152 patients. 832 52

Computed tomography (CT) plays an important role in evaluation and management of primary renovascular disease. Nonenhanced CT is useful for demonstrating renal hemorrhage, renal parenchymal or vascular calcifications, and masses. Contrast material-enhanced CT is essential to identify global or regional nephrographic abnormalities resulting from the vascular process (eg, renal infarcts, ischemia secondary to renal artery stenosis, arteriovenous communications). In addition, renal manifestations of a systemic disease (eg, vasculitis, thromboembolic disease) can be seen at CT. In trauma, occlusion of the main renal artery can be accurately diagnosed with contrast-enhanced CT. In cases of spontaneous renal hemorrhage without an apparent cause (eg, vasculitis, coagulopathy), a careful CT study should be performed to exclude renal cell carcinoma. The presence of fat in a hemorrhagic renal mass larger than 4 cm in diameter is characteristic of angiomyolipoma complicated by hemorrhage. Acute renal vein thrombosis appears as a clot in a distended renal vein, whereas renal vein retraction with collateral vessels is highly indicative of chronic thrombosis. Helical CT, especially with multiplanar two-dimensional and three-dimensional reconstruction following an intravenous injection of iodinated contrast material, has greatly improved our ability to directly image the proximal renal arteries and detect vascular lesions.
 ...
PMID:CT evaluation of renovascular disease. 1099 21


1 2 3 4 5 6 7 8 Next >>