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Y Lu

Publications and source records attributed to Y Lu.

At least 955 records · Page 53Linked to original sources
PubMed1989

[Idiopathic perilymph fistula].

This article presents 6 cases with idiopathic perilymph fistulae. The etiology of idiopathic perilymph fistula may be congenital malformation of the otic capule. Diagnosis of idiopathic perilymph fistula primarily depends on history and exploratory tympanotomy, but ENG-fistula test and positional audiometry are worth of diagnosing. During microsurgical procedure, attention must be paid to the presence of membrane of the round window niche. If a good repair of fistula is not followed by a good result, other lesions such as double labyrinth membrane rupture should be considered.

Adult↗
PubMed1989

The therapeutic efficacy of the choleretic mixture against the infantile hepatitis syndrome.

Observation was made on a control study of the therapeutic efficacy of the choleretic mixture in treating 35 cases of infantile hepatitis syndrome in comparison with that of the choleretic decoction. The ages, duration of the disease, severity of icterus and serum bilirubin level in both groups were comparable. The results showed that there was no significant difference in therapeutic efficacy between the two groups, however, the resolving time of skin icterus was faster in the choleretic mixture group than in the choleretic decoction group. The choleretic mixture was convenient, easy to store, and acceptable to infants for its small dosage, and no side effects, therefore, a desirable drug against infantile hepatitis syndrome.

Drugs, Chinese Herbal↗
PubMed1988

Detection of drug resistance in human tumors by in vitro enzymatic amplification.

Both acquired and natural resistance to chemotherapy agents have proved problematic in the treatment of neoplasia. Thymidylate synthase, which catalyzes the synthesis of thymidine precursors, has been shown to be amplified in response to a variety of chemotherapeutic agents. The detection of such amplification could prove beneficial in the development of alternative clinical protocols. In this study we report the use of existing enzymatic amplification methods in order to detect incipient amplification of the thymidylate synthase gene upon resistance to cisplatin. The assay utilizes a modification of the polymerase chain reaction in which a sequence of the thymidylate synthase gene is amplified including two flanking oligonucleotides acting as primers for DNA synthesis. This method exhibits greater sensitivity than conventional nucleic acid detection methods and requires less than 100 ng of total RNA from patient tumors and no in vitro culturing of patient cells.

Cell Line↗
PubMed1988

Biochemical and molecular properties of cisplatin-resistant A2780 cells grown in folinic acid.

In this study, A2780 human ovarian carcinoma cells were grown in folinic acid in contrast to folic acid, and the molecular and biochemical properties of cisplatin-resistant A2780 cells were analyzed for changes in the dTMP synthase cycle. At concentrations of folinic acid that were optimal for cell growth (10(-8) M), the ED50 for cisplatin was 2.5 and 43 microM in the A2780S and A2780DDP cells, respectively. Resistance to cisplatin was associated with a 2-fold cross-resistance to 5-fluorodeoxyuridine and 5-fluorouracil as well as a 3-fold increase in both dTMP synthase activity and mRNA. The ED50 for methotrexate was similar in both A2780S and A2780DDP cells (1.2 microM). When both the A2780S and A2780DDP cells were grown in folinic acid, there was no significant difference in the level of dihydrofolate reductase activity. This data would suggest that cisplatin resistance is associated with changes in folate metabolism.

Cell Line↗
PubMed1988

Mechanisms of cross-resistance to methotrexate and 5-fluorouracil in an A2780 human ovarian carcinoma cell subline resistant to cisplatin.

Some properties of the human ovarian carcinoma line A2780 and a subline three times more resistant than the parent line to cisplatin are compared in this report. The rates of uptake and release of cisplatin were similar in the two cell lines. Resistance to cisplatin was associated with: (a) cross-resistance to 5-fluorouracil and methotrexate; (b) a 2.5-fold increase in thymidylate synthase, as measured by both enzyme activity and the capacity to complex 5-fluorodeoxyuridylate; and (c) an increase in the intracellular pools of 5,10-methylenetetrahydrofolate and tetrahydrofolate. These data suggest that cross-resistance to 5-fluorouracil and methotrexate in A2780 cells may be a consequence of increases in their respective target enzymes.

Biological Transport↗
PubMed1988

Mechanisms for cisplatin-FUra synergism and cisplatin resistance in human ovarian carcinoma cells both in vitro and in vivo.

Cisplatin and FUra act synergisticly in human carcinomas. An increase in the availability of reduced folates necessary for tight binding of FdUMP to thymidylate synthase (TS) contributes to the enhanced cytotoxicity of this drug combination. The human ovarian A2780 cell line made three-fold resistant to cisplatin has been shown to have a three-fold elevation of m-RNA for dihydrofolate reductase (DHFR) and TS. However, this increase did not result from an amplification of the genes for these two enzymes. In contrast, ovarian carcinoma cells from patients who failed treatment with cisplatin and FUra have been shown to have both enhanced gene expression and increased gene copy number for DHFR and TS.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1988

Successful replantation in ten-digit complete amputations.

The authors report a case of successful replantation of all fingers in a ten-finger complete amputation. Among the factors responsible for the successful outcome were an adequate number of microsurgically-trained resident surgeons and staff, good organization and supervision by senior staff, emphasis on precision and perseverance in the operative procedures, and postoperative management. Follow-up is 15 months, and the patient now has a pair of functionally and cosmetically good hands.

Adult↗
PubMed1987

Use of capillary blood for the evaluation of iron status.

The accuracy and precision of measurements of iron status made on the capillary blood from a single 75 X 1-mm microhematocrit tube were evaluated in 301 normal volunteers. After recording the hematocrit value, a hematofluorometer was used to assay erythrocyte protoporphyrin directly on the packed red cell fraction. Values in the low normal range were 50-100% higher than assays by an extraction technique in simultaneously collected venous blood. However, measurements in the iron deficient range were only 12% greater. Plasma ferritin concentration was determined by using an enzyme-linked immunoassay on 10-microliters plasma retrieved after measuring the hematocrit. Capillary values were approximately 7% higher than venous concentrations, the proportional difference being consistent throughout the measured range. When the individual measurements were combined to calculate the iron storage status of each individual, the frequency distribution of iron stores in 141 female volunteers between 18 and 36 years of age was approximately Gaussian and paralleled that calculated for women aged 18-44 years in NHANES II. These studies demonstrate that iron status can be determined accurately from the measurement of hematocrit, erythrocyte protoporphyrin, and ferritin on a single microhematocrit tube of capillary blood.

Adolescent↗
PubMed1986

Biomembranes as models for polymer surfaces. IV. ESCA analyses of a phosphorylcholine surface covalently bound to hydroxylated substrates.

Using a simple chemical process, phosphorylcholine has been deposited covalently on the surface of a variety of hydroxylated polymers as a stable, monomolecular coating. Our goal was to obtain new biomaterials which, due to the chemical similarity of the modified interfaces to the phospholipid head groups present on the extracellular surfaces of blood cell membranes, should exhibit enhanced haemo- and biocompatibility. Our previous analyses by chemical and spectrophotometric methods indicated that sufficient quantities of phosphorylcholine were deposited on glass and silica surfaces to result in appreciable modification of their interfacial properties. In the present study, we have examined a series of modified hydroxylated substrates by ESCA and demonstrate specific chemical modifications on the molecular surfaces of polymeric substrates.

Chemical Phenomena↗
PubMed1986

Biochemical basis for cisplatin and 5-fluorouracil synergism in human ovarian carcinoma cells.

The human ovarian cell line A2780 was exposed to either cisplatin (10 microM) or 5-fluorouracil (5FUra) (5 microM) for 1 hr. Cytotoxicity was less than 14% with either agent alone. Cisplatin (10 microM) and 5FUra (5 microM) in combination for 1 hr caused a 76% reduction in cell growth. Thymidine (dThd, 10 microM), if given concomitantly with the combination of cisplatin and 5FUra, completely protected the tumor cells. A 30-min exposure to cisplatin increased the intracellular pools of 5,10-methylenetetrahydrofolate and tetrahydrofolate 2.5-fold. The capacity of intact cells to form 5-fluorodeoxyuridylate (FdUMP)-thymidylate (dTMP) synthase complex when incubated with fluorodeoxyuridine (FdUrd) was enhanced 2.5-fold when the cells were pretreated with cisplatin. These experiments demonstrate that cisplatin can increase the availability of the reduced folate necessary for tight binding of FdUMP to dTMP synthase, thus enhancing the cytotoxicity of the cisplatin and 5FUra combination.

Carcinoma↗