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61.
62.
Primary hyperoxaluria type 1 is a rare inherited disorder caused by abnormal liver glyoxalate metabolism leading to overproduction of oxalate, progressive kidney disease, and systemic oxalosis. While the disorder typically presents with nephrocalcinosis, recurrent nephrolithiasis, and/or early chronic kidney disease, the diagnosis is occasionally missed until it recurs after kidney transplant. Allograft outcomes in these cases are typically very poor, often with early graft loss. Here we present the case of a child diagnosed with primary hyperoxaluria type 1 after kidney transplant who was able to maintain kidney function, thanks to aggressive renal replacement therapy as well as initiation of a new targeted therapy for this disease. This case highlights the importance of having a high index of suspicion for primary hyperoxaluria in patients with chronic kidney disease and nephrocalcinosis/nephrolithiasis or with end stage kidney disease of uncertain etiology, as initiating therapies early on may prevent poor outcomes.  相似文献   
63.
Five recombinant antigens (Ags; 85A, 85B, 85C, superoxide dismutase [SOD], and 35-kDa protein) were purified from Mycobacterium avium subsp. paratuberculosis and evaluated for their ability to stimulate peripheral blood mononuclear cells (PMBCs) from fecal-culture-positive cows (low and medium shedders) and culture-negative healthy cows. Recombinant Ags 85A, 85B, and 85C induced significant lymphocyte proliferation as well as the production of gamma interferon (IFN-gamma), interleukin-2 (IL-2), IL-12, and tumor necrosis factor alpha (TNF-alpha), but not IL-4, from low and medium shedders. The 85 antigen complex did not stimulate PMBC proliferation from culture-negative healthy cows. The 35-kDa protein also induced significant lymphocyte proliferation as well as the production of IFN-gamma and IL-4 from low and medium shedders. CD4(+) T cells and CD25(+) (IL-2R) T cells were stimulated the most by 85A and 85B, while the 35-kDa protein primarily stimulated CD21(+) B cells involved in humoral immune responses. Interestingly, SOD was less immunostimulatory than other antigens but strongly induced gammadelta(+) T cells, which are thought to be important in the early stages of infection, such as pathogen entry. These data provide important insight into how improved vaccines against mycobacterial infections might be constructed.  相似文献   
64.
Cocaine increases myocardial oxygen demand and paradoxically decreases oxygen supply by reducing coronary blood flow. Such "inappropriate" vasoconstriction also occurs with exercise, which causes intense vasoconstriction of coronary artery segments narrowed by atherosclerosis. This study was done to assess the cocaine-induced change in vasomotor tone of diseased and nondiseased coronary artery segments. In 18 patients (15 men, 3 women, aged 35 to 67 years), coronary artery areas in diseased and nondiseased segments were quantitated before and 15 min after administration of intranasal saline solution (6 patients) or cocaine (2 mg/kg body weight) (12 patients). No variables changed after intake of the saline solution. In response to cocaine, the luminal areas of diseased and nondiseased segments decreased, but the magnitude of vasoconstriction was greater in the diseased segments (mean +/- SD 29 +/- 23% versus 13 +/- 8%, p less than 0.05). Thus, cocaine causes vasoconstriction of diseased and nondiseased coronary artery segments, but its effect is particularly marked in the former.  相似文献   
65.
Highly aggressive murine B16 melanoma was engineered to secrete IFN-alpha constitutively. Cells expressing IFN-alpha were injected into syngeneic C57BL/6 mice and the mice were monitored for tumor development. Secretion of IFN-alpha by B16 melanoma cells completely abrogated their tumorigenicity in syngeneic mice. LFN-alpha-secreting cells also abrogated the tumorigenicity of IFN-gamma-secreting and TNF-alpha-secreting cells when injected in combination whereas cells secreting either IFN-gamma or TNF-alpha grow progressively in mice when injected alone. Moreover, protected animals developed significant immunity against subsequent challenge with parental cells. Injection of parental cells and IFN-alpha-secreting cells together in a mixed tumor transplantation assay resulted in a significant reduction of tumorigenicity of the parental cells. Histopathological studies of the tissues from the injection site of the mice inoculated with a combination of parental and B16.IFN-alpha cells revealed the existence of a massive cellular infiltrate composed of lymphocytes and granulocytes at an early stage (7-11 days). In the later stages (22 days), no recognizable tumor tissue was detected. Injection of irradiated IFN-alpha-secreting cells in the mice carrying an established tumor completely prevented tumor development in 80% of the treated mice when injection was performed on the same side as the tumors. Injection of irradiated IFN-alpha-secreting cells in the contralateral site showed much less effect on the established tumor. Systemic antitumor effects on the established tumor can be enhanced by using a combination of irradiated IFN-alpha and IFN-gamma secreting cells as a vaccinating inoculum.  相似文献   
66.
The possibility of using L-meta-tyrosine (L-mTyr) with high metabolic stability and amino acid transport affinity was evaluated. mTyr was first separated into D- and L-isomers with high-performance liquid chromatography and both were labelled with non-carrier-mediated 125I. Biodistribution and pharmacological studies of radioiodinated mTyr in mice and rats were then performed. 125I-L-mTyr showed greater accumulation in the brain and the pancreas. It accumulated in the brain stereospecifically in the in vivo studies and by the L-tyrosine competitive energy dependent transport system in the in vitro studies. It was resistant to deiodination, appeared to have no retention mechanism and was rapidly excreted. 123I-L-mTyr has the potential of an amino acid transport marker, especially in the brain and the pancreas.  相似文献   
67.
We report a strange case of a bladder whose first metastasic manifestation, after two years of the diagnosis, was a peripheric polyneuropathia. This patient was treated with immunotherapy with BCG for superficial carcinoma of the bladder during one year. Gradually central neurological symptoms appeared and the patient died one month later. A meningeal carcinomatosis was identify as the cause. No bone metastases existed, which is the most frequent way of tumours extension towards leptomeninges. We argue about the way to arrive at meninges.  相似文献   
68.
We describe a case of metastatic nephroblastoma presenting as renal rupture. Histology was "favorable". Lung metastases were discovered early during follow-up. Radiotherapy and surgical excision were therefore combined with intensive chemotherapy. Ten years later, the patient is symptom-free.  相似文献   
69.
Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis.  相似文献   
70.
To find out if Cantrell's pentad is a single entity, four cases of ectopia cordis were studied and compared with cases in the literature. Our cases had the heart outside the thorax and had two to four other features of the association. In one case the thoracic organs had apparently escaped through a diaphragmatic hernia into an omphalocele, and in the others via a thoracoschisis with an abdominal defect, either a supraumbilical hernia or a gastroschisis. According to these cases and those from the literature, it is proposed that there are two major mechanisms leading to ectopia cordis: (1) a reversed diaphragmatic hernia in the case of a large diaphragmatic defect and an omphalocele, and (2) through a sterno-costal defect, with gastroschisis or a supraumbililical abdominal defect. As omphaloceles and major diaphragmatic defects are probably pathogenetically distinct from thoraco- and thoracogastroschisis, it is important to distinguish these groups of anomalies, rather than be concerned as to their relationship with Cantrell's pentad.  相似文献   
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