PubMed Health⌕ Search

Biomedical subjects

N Tsai

Publications and source records attributed to N Tsai.

14 recordsLinked to original sources

Fatal hepatorenal failure associated with hydrazine sulfate.

BACKGROUND: The Internet has revolutionized the manner in which patients obtain information about health care. This technology has also allowed patients to obtain directly both prescription and nonprescription therapies. OBJECTIVE: To report a case of fulminant hepatorenal failure associated with the use of hydrazine sulfate, an unregulated alternative remedy for cancer marketed on the Internet. DESIGN: Case report. SETTING: Academic medical center. PATIENT: A 55-year-old man with maxillary sinus cancer. INTERVENTION: Self-medication with hydrazine sulfate. MEASUREMENTS: Serum liver and renal function tests; histologic evaluation of liver and kidney tissue. RESULTS: The patient developed hepatic encephalopathy, renal failure, and profound coagulopathy. He died after severe gastrointestinal hemorrhage developed. Autopsy revealed autolysis of the kidneys and submassive bridging necrosis of the liver. CONCLUSION: Fatal hepatorenal failure may occur after the use of hydrazine sulfate. This fatal complication must be considered in anyone taking or contemplating the use of hydrazine sulfate.

Antineoplastic Agents↗

Authors' reply

Explore the source record for details and available documents.

Journal Article↗

VEGF induces nuclear translocation of Flk-1/KDR, endothelial nitric oxide synthase, and caveolin-1 in vascular endothelial cells.

VEGF increases endothelial cell permeability and growth by a process requiring NOS activity. Because eNOS activity is regulated by its interaction with the caveolar structural protein caveolin-1, we analyzed VEGF effects on structural interactions between eNOS, caveolin-1 and the VEGF receptor Flk-1/KDR. Confocal immunolocalization analysis of the subcellular distribution of Flk-1/KDR, caveolin-1 and eNOS showed that VEGF stimulated the translocation of all three proteins into the nucleus. This result was confirmed by cell fractionation and immunoblotting studies showing that levels of all three proteins within the caveolar compartment declined progressively after 30 and 60 min of VEGF treatment. The pattern was reversed for nuclear fractions. Protein levels were lowest in the control cultures, but increased progressively after 30 and 60 min of treatment. Nuclear translocation of eNOS and Flk-1/KDR within caveolae may represent a mechanism for targeting NO production to the nuclear compartment where it could influence transcription factor activation.

Animals↗

Detection of choroidal calcium by computed tomography scan quantitative computerized tomography: a clinically useful diagnostic tool.

OBJECTIVE: Quantitative computerized tomography (QCT), a scanning method routinely used to classify tissues based on their radio density, was used to detect choroidal calcification. DESIGN: Case reports. PARTICIPANTS: Two patients with known or suspected choroidal calcium-choroidal osteoma (CO) and pseudoxanthoma elasticum (PXE) and five normal control subjects were assessed. INTERVENTION: The CT scan of choroid, B-scan ultrasound, fluorescein angiography. MAIN OUTCOME MEASURES: The QCT scan used to detect the presence of calcium based on a readout greater than 90. RESULTS: Calcium was detected bilaterally, as predicted, in PXE, and in both eyes of CO, although only one eye had a clinically noted lesion. No control eye gave a scale readout consistent with calcium. No findings suggestive of calcium were noted with B-scan ultrasound or fluorescein angiography in PXE or CO. CONCLUSION: The QCT can detect calcium in the choroid when B-scan ultrasonography and CT scan fine sectioning fail to identify calcium despite high clinical suspicion.

Adult↗

VEGF-induced permeability increase is mediated by caveolae.

PURPOSE: To determine the cellular route by which vascular endothelial cell growth factor (VEGF) increases the permeability of cultured retinal endothelial cells and to test whether nitric oxide (NO) production by NO synthase (NOS) is involved in signaling VEGF's permeability enhancing effects. METHODS: Cultured bovine retinal microvascular endothelial (BRE) cells were used for bioassay of permeability function and its ultrastructural correlates. The role of NOS activity in VEGF's permeability enhancing effects was tested with the use of an NOS inhibitor. Because activity of endothelial NOS (eNOS) is thought to be regulated by its interaction with the caveolar protein caveolin-1, structural relationships between eNOS, caveolin-1, and the VEGF receptor FIk-1/KDR were analyzed with double-label immunofluorescence and cell fractionation procedures. RESULTS: Bioassays of permeability function and structure demonstrated that VEGF increases permeability of cultured BRE cells by an NOS-dependent process of transcytotic transport in caveolae. Double-label analysis showed that Flk-1/KDR and eNOS colocalize with caveolin-1 in plasma membrane caveolae. Cell fractionation and immunoblot analysis confirmed this effect. Densitometry showed that Flk-1/KDR, eNOS, and caveolin-1 levels were highest in caveolar fractions. Similar results were obtained in studies with bovine aortic endothelial cells. CONCLUSIONS: These results demonstrate that VEGF increases endothelial cell permeability by an eNOS-dependent mechanism of transcytosis in caveolae. Localization of Flk-1/KDR and eNOS with caveolin-1 suggests that VEGF signaling occurs within the caveolar compartment.

Actins↗

Induction of aquaporin-1 mRNA following cardiopulmonary bypass and reperfusion.

BACKGROUND: Cardiopulmonary bypass (CPB) and hypothermic circulatory arrest (HCA) are important components of congenital cardiac surgery. Ischemia/reperfusion injury and inflammatory cascade activation result in endothelial damage and vascular leak which are clinically manifested as pulmonary edema and low cardiac output postoperatively. Newborns are particularly susceptible. Subtraction cloning is a useful method of isolating induced genes and can be applied to CPB/HCA. MATERIALS AND METHODS: We used a newborn lamb model replicating infant CPB with HCA to obtain tissues during various periods of reperfusion. We utilized subtraction cloning to identify mRNA induced in lung following CPB/HCA and reperfusion. Ribonuclease protection was used to quantify mRNA levels. RESULTS: We isolated a cDNA encoding ovine aquaporin-1 in a subtracted cDNA screen comparing control lung with lung exposed to CPB/HCA and reperfusion. Aquaporin-1 mRNA levels increased 3-fold in lung (p = .006) exposed to CPB/HCA and 6 hr of reperfusion. No induction was observed immediately following bypass or after 3 hr of reperfusion. We found no significant induction of aquaporin-1 mRNA following bypass, arrest, and reperfusion in other tissues surveyed, including ventricle, atrium, skeletal muscle, kidney, brain, and liver. CONCLUSIONS: Our finding that aquaporin-1 mRNA is reproducibly induced in lung following CPB/HCA with 6 hr of reperfusion suggests an important role for the water channel in the setting of pulmonary edema. Induction of Aquaporin-1 is late compared with other inflammatory mediators (ICAM-1, E-selectin, IL-8). Further studies are needed to determine if aquaporin-1 contributes to the disease process or if it is part of the recovery phase.

Amino Acid Sequence↗

Pharmacological profiles of fentanyl analogs at mu, delta and kappa opiate receptors.

Receptor binding assays using [3H]DAGO ([D-Ala2,MePhe4-Gly5-ol]enkephalin) (mu), [3H]DPDPE ([D-Pen2,D-Pen5]enkephalin) (delta) and [3H]U-69593 (kappa) were done in guinea pig whole brain membranes. Agonist activity was determined in norbinaltorphimine or beta-funaltrexamine (beta-FNA) treated guinea pig ileum (mu and kappa, respectively) and beta-FNA-treated mouse vas deferens (delta). The compounds with highest affinity were the most potent at the mu-receptor. The selectivity observed in the binding affinities was also found in in vitro activity. No correlation was found between mu-affinity and selectivity; the highest affinity analog, lofentanil, was found to be among the least selective, while another high affinity analog, R30490, was the most mu-selective. The results show that not all fentanyls are highly mu-selective, and could produce actions through delta- and kappa-opiate receptors.

Analgesics, Opioid↗

Denial of lineage: clinical investigation of 50 cases.

Fifty randomly selected Chinese schizophrenic patients with denial of lineage were investigated. This delusion concerns the generation of parents, sisters, but not the offspring. Twenty-four of them manifested delusion of high-ranking lineage or of distinguished leadership lineage. Denial of lineage, involving the delusion of high-ranking lineage and the delusion of leadership lineage, may occur at the onset or during the course of schizophrenia. The clinical characteristics of this delusion are described and its concept, diagnosis, differential diagnosis, course and also possible mechanism are discussed. One possible mechanism is of psychodynamical origin. Emotional conflicts resulting from dissatisfaction of the primary need of being loved from birth may contribute to the onset of the denial of lineage. The second possible mechanism is a sociocultural fact. Far Eastern culture is based on the clan whereas occidental culture is based on the self. Thus can observe the denial of lineage in the Far East, but in the occident we can experience instead the idea of surmounting our self so as to be god or now to experience the omnipotence in form of technical ideas, e.g. the rays.

Adult↗

[Diagnosis and taxonomy of periodical psychosis].

The concept and taxonomy of periodic psychosis still remains in controversy for the past 100 years. In China, it was first reported by Ji, and thereafter various rinds of terminology and views were given by different authors. In the presentation, clinical investigation and follow up were carried out in 62 cases. In many of these cases, the so-called "periodic psychosis" or "phasophrenia" was early clinical features of schizophrenia or manic-depression. In those cases with apparent symptoms and signs of diencephalic function, differential diagnosis should be carried out from organic brain syndrome. In a small number of cases, their clinical manifestations, conforming to previous diagnostic criteria, might be an uncommon syndrome. It was concluded by the authors that until now periodic could be considered only as a clinical syndrome rather than a disease entity.

Bipolar Disorder↗

Acute infectious torticollis.

Acute torticollis has occurred in epidemics in eastern and northern China since 1975, but has not yet been reported in other countries. A general account of this disease, including its terminology, epidemiology, clinical features, laboratory findings, diagnosis, differential diagnosis, and treatment, is presented. The etiology, though highly suggestive of a virus infection, remains to be determined.

Acute Disease↗

Gastrointestinal problems in the elderly.

Gastrointestinal problems in the elderly, such as swallowing difficulties, chest pain, bleeding, constipation, and colonic diseases, which may present problems in diagnosis or management, are discussed. A screening procedure for colorectal cancer in asymptomatic geriatric patients is proposed.

Aged↗

Transcultural investigation of recent symptomatology of schizophrenia in China.

During the past 15 years a number of new symptoms, rarely seen in the past, have been observed with increasing frequency among Chinese schizophrenic patients. The authors identify the following symptoms: discordant (dissociative) syndrome, denial of lineage, delusion of leadership lineage, delusion of being married, child-bearing delusion, delusion of being despised, delusion of imminent catastrophe, delusion of influence, inferential delusion, delusion of being experimented on, delusion of conducting an experiment, delusion of being cultivated by superiors, delusion of being tested, delusion of being examined, delusion of impending arrest, delusion of being slandered, mirror symptom, and syndrome of changing dialects.

China↗