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921.
K Haneda M P Sands R Thomas E A Hessel D H Dillard 《The Journal of cardiovascular surgery》1983,24(1):15-21
Twenty-nine adult mongrel dogs were subjected to profound hypothermia and 90 minutes of total circulatory arrest. Pure surface (Group I) hypothermia and combined surface/perfusion techniques with bubble (Group II) and membrane (Group III) oxygenator systems were employed. Circulation was arrested at average esophageal temperatures of 18.4 degrees, 11.9 degrees and 8.5 degrees C in Groups I, II and III, respectively. Three animals in Group I failed to resuscitate. All survivors in the pure surface series developed postoperative gait (hypermetria) disturbances. One intraoperative death occurred in Group II and four of eight dogs arrested at esophageal temperatures above 10 degrees C but less than 15 degrees C developed motor disturbances during a three week neurologic evaluation period. Animals arrested below 10 degrees C (esophageal) did not display postoperative neurological abnormalities. Three dogs in Group III died from a hemorrhagic diathesis of uncertain etiology. None of the survivors (5) that were cooled and arrested below esophageal temperatures of 10 degrees C developed motor or sensory disturbances. We conclude that in the canine model the central nervous system can be protected for 90 minutes of total circulatory arrest at esophageal temperatures less than 10 degrees C. 相似文献
922.
Goodpasture's syndrome in identical twins 总被引:3,自引:0,他引:3
923.
924.
A32390A is an isonitrile-containing derivative of diacyl D-mannitol. The compound is produced in fermentation as the major component of a metabolic complex known as A32390. A32390A inhibits dopamine-beta-hydroxylase reduces heart and adrenal norepinephrine levels, lowers blood pressure in hypertensive rats, and possesses antibiotic activity vs. Gram-positive bacteria and fungi, including Candida albicans. A32390 is produced in submerged culture by a mold, a species of Pyrenochaeta, NRRL-5786. Glucose and sucrose are among the best carbon sources for the biosynthesis of A32390. Mannitol, although a substituent of the A32390A molecule, supports little or no biosynthesis of the compound when employed as the major carbon source for the fermentation. The addition of crotonic acid derivatives. ethanol, or L-histidine to the fermentation medium enhances the level of A32390 produced. 相似文献
925.
Mango RL Xu L Sands MS Vogler C Seiler G Schwarz T Haskins ME Ponder KP 《Molecular genetics and metabolism》2004,82(1):4-19
Mucopolysaccharidosis VII (MPS VII) is a lysosomal storage disease caused by deficient beta-glucuronidase (GUSB) activity. Accumulation of glycosaminoglycans (GAGs) in bone, cartilage, and synovium likely contributes to reduced mobility in untreated MPS VII individuals. We previously reported that neonatal intravenous injection of a retroviral vector (RV) expressing canine GUSB resulted in hepatocyte transduction in mice and dogs, and secreted GUSB was taken up from blood by other organs. Here we report the effect of this therapy on bone, cartilage, and joint disease. Osteocytes and bone-lining cells from RV-treated MPS VII mice had GUSB activity, resulting in a marked reduction, as compared with untreated MPS VII mice, in lysosomal storage in bone and at the bone:growth plate interface where bone elongation occurs. Although chondrocytes did not have detectable GUSB activity and had little reduction in lysosomal storage, the thickness of the growth plate was reduced toward normal. These pathological changes were likely responsible for improvements in facial morphology and long bone lengths. The synovium had reduced hyperplasia and lysosomal storage, and the thickness of the articular cartilage was reduced. Similarly, RV-treated MPS VII dogs had improved facial morphology and reduced lysosomal storage in osteocytes and synovium, but not chondrocytes. Nevertheless, the internal area of the trachea was increased, and erosions of the femoral head were reduced. We conclude that neonatal gene therapy can improve bone and joint disease in MPS VII mice and dogs. However, better delivery of GUSB to chondrocytes will be necessary to achieve more profound effects in cartilage. 相似文献
926.
Due to the development of more effective medications, those infected with HIV are living longer. Consequently, more tumors and infections have been added to the AIDS-defining criteria in the last decade. Our aim was to review the occurrence and clinical course of colorectal (CR) malignancies in HIV infected/AIDS patients from a single institution. A retrospective review of HIV/AIDS patients with colorectal malignant tumors was undertaken. We included adult patients, with ELISA and Western blot test positive for HIV, and primary malignant tumors located in the colon or rectum. Malignant neoplasms of the anus were excluded for the purposes of this study. Twelve patients (9 males and 3 females), mean age 41 years, were identified with the following neoplasm: 6 adenocarcinomas (ACA), 5 non-Hodgkin lymphomas (NHL), and 1 small-cell carcinoma. Intravenous drug abuse was the main risk factor for HIV. No patient had identified risk factors for colorectal neoplasm. Five out of six patients with ACA had metastatic disease at the time of diagnosis. One patient with stage II ACA developed early liver metastases after colonic resection. Seven out of 12 patients underwent surgery. Six (85.7%) of these sustained postoperative complications, primarily wound infection. The overall survival in our series was dismal, averaging 20 months. For NHL average survival was 29 months, and 12 months for CR-ACA. This is the largest series of cases of colorectal cancer in the HIV/AIDS patient population published in the English language and the largest number of colorectal ACA reported in this unique population. Early in our experience, tumors frequently found in immunoincompetent patients were detected (NHL). More recently, we have only treated patients with colorectal ACA; none of them had no risk factors for colorectal cancer (family history, IBD, FAP, HNPCC). These patients developed tumors at earlier ages and were diagnosed at an advanced stage. Therefore, these tumors may be associated with the grade of immunosuppression induced during the course of the HIV infection and with a tumorigenic effect of the HIV on the colonic epithelium. Consequently, a high index of suspicion when evaluating chronic abdominal complaints in such patients is warranted. The use of the new antiretroviral therapy regimens should be further evaluated to know its impact in the survival. 相似文献
927.
Nemunaitis J Cunningham C Tong A Post L Netto G Paulson AS Rich D Blackburn A Sands B Gibson B Randlev B Freeman S 《Cancer gene therapy》2003,10(5):341-352
ONYX-015 is an adenovirus that selectively replicates in p53 dysfunctional or mutated malignant cells. We performed a pilot trial to determine the safety and feasibility of treatment with ONYX-015 delivered intravenously in patients with advanced malignancy. One cohort of five patients received ONYX-015 once a week for 6 weeks at a dose of 2 x 10(12) particles per infusion in combination with weekly infusions of irinotecan (CPT11, 125 mg per week) and 5-fluorouracil (5FU, 500 mg per week). A second cohort of five patients received the combination of ONYX-015 at a dose of 2 x 10(11) particles per week for 6 weeks in combination with interleukin 2 (IL 2, 1.1 x 10(6) units daily via subcutaneous injection for 5 days each week for 4 weeks). Toxicity attributable to ONYX-015 was limited to transient fever. All patients demonstrated elevations in neutralizing antibody titers within 4 weeks of the infusion of ONYX-015. Serum levels of IL-6, IL-10, tumor necrosis factor-alpha, and interferon-gamma increased within 6 hours of viral infusion, suggesting immune activation. This response was more pronounced in the cohort of patients who received 2 x 10(12) particles per infusion. Two patients demonstrated uptake of viral particles in malignant tissue by quantitative PCR. Electron microscopy confirmed selective cytoplasmic viral particles within malignant cells but not within adjacent normal tissue in a third patient. In conclusion ONYX-015 can be administered safely in combination with CPT11, 5FU or low-dose IL 2 and is able to access malignant tissue following intravenous infusion. Further investigation of ONYX-015, possibly with agents that may modulate replication activity, or duration of virus survival, is indicated. 相似文献
928.
929.
930.
A case of testicular plasmacytoma is described at the light and fine structure level. The patient was a 54-year-old male with a history of multiple myeloma.The testicular tumor was restricted to an interstitial space growth. Plasma cells varied in differentiation with few obtaining the cartwheel nucleus and prominent Golgi of connective tissue plasma cells. Cytoplasmic inclusions were characteristic of most cells and a large number of intranuclear inclusions were present. To our knowledge, this is the first report of such inclusions in the cells of a testicular plasmacytoma. Their significance in cases of end stage myeloma is discussed. 相似文献