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111.
W Reed TH Lee EP Vichinsky BH Lubin MP Busch 《Canadian Metallurgical Quarterly》1998,38(11-12):1041-1045
BACKGROUND: There is increasing use of highly sensitive testing with polymerase chain reaction (PCR) to study white cell microchimerism after transfusion and transplantation. This study investigated possible artifactual sources of allogeneic sample contamination before PCR testing. STUDY DESIGN AND METHODS: Quantitative Y-chromosome PCR was used to study microchimerism among transfused patients with sickle cell disease (SCD) and thalassemia by using residual specimens from the clinical laboratory. High levels of circulating male white cells among transfused patients with SCD but not thalassemia led to concern over the artifactual origin of male cells. To investigate, paired specimens were collected from 26 female SCD patients: one specimen underwent processing only for PCR, while the other underwent testing in the clinical laboratory before PCR as a process control. All laboratory instruments were also assessed for their ability to impart male allogeneic cells to aliquots of female blood. RESULTS: Thirty-three (31%) of 107 SCD samples, but 0 of 20 thalassemia samples, gave a high-level PCR signal. One of 26 paired samples that was not exposed to clinical laboratory equipment had low-level PCR positivity while 10 of the 26 became strongly positive after testing on a blood cell analyzer and a reticulocyte analyzer. Sixteen of 32 female samples became positive after reticulocyte analysis, while none became positive after blood cell analysis. Samples from thalassemia patients tested PCR-negative because reticulocyte counts had not been performed. CONCLUSION: Allogeneic cell contamination is common with clinical laboratory equipment. These samples may not be suitable for microchimerism studies. In addition to method controls, process controls should be employed where appropriate. 相似文献
112.
A benign, transient proliferation of atypical lymphocytes and a monoclonal rearrangement of the T-cell receptor beta (TRB) locus was found in a 60-year-old woman who presented with low-grade fever, anorexia and fatigue. A marked and transient atypical lymphocytosis (white blood cell count 90.5 x 10(9)/l) with CD8 surface antigen improved without specific treatment. Although tests for IgM antibodies to hepatitis A, varicella zoster, Epstein-Barr virus (EBV), and cytomegalovirus (CMV) were all negative, a monoclonal gene rearrangement of TRB locus was observed in the DNA of the proliferated atypical lymphocytes by Southern blotting. The clonal rearrangement and the atypical lymphocytes disappeared after 14 d, and the patient has remained well for 7 years. These results suggest that monoclonal proliferation of CD8 lymphocytes can occur based on a non-neoplastic aetiology. 相似文献
113.
Estrogen replacement therapy in postmenopausal women must be combined with progestin to avoid endometrial cancer. However, progestin addition could antagonize cardioprotective effects of estradiol. Therefore we investigated the effect of the two most commonly used progestins--medroxyprogesterone acetate (progesterone-derivative) and norethisterone acetate (nortestosterone-derivate)--alone and in combination with 17 beta-estradiol on copper-mediated oxidation of low density lipoprotein (LDL). Whereas 17 beta-estradiol alone inhibited the onset of LDL oxidation at the concentrations 0.5, 1.0, 5 and 10 microM, the progestins alone did not demonstrate any significant effect. In the estrogen-progestin combinations of 0.5 microM 17 beta-estradiol with 0.5, 1.0, 5 and 10 microM progestin, respectively, the estradiol effect was not changed. These results suggest that medroxyprogesterone acetate as well as norethisterone acetate do not counteract the beneficial effect of 17 beta-estradiol on LDL oxidation when used in hormone replacement therapy. 相似文献
114.
The sequential changes of natural killer cell (NK) activity and prostaglandin E2 (PGE2) during hepatocarcinogenesis induced by diethylnitrosamine (DEN) in male Fischer 344 rats were investigated. DEN at a concentration of 40 ppm was administered in drinking water for 10 weeks. At weeks 5, 10, 20 and 30, rats were autopsied and the development of glutathione S-transferase placental form positive foci (GST-P+ foci) at weeks 5 and 10 and hepatocellular tumors at weeks 20 and 30 were examined. The labeling index of bromodeoxyuridine (BrdU) an indicator of DNA synthesis, was also sequentially checked. GST-P+ foci were found to increase with age. Hepatocellular nodules increased until week 20, but by week 30 when the incidence of hepatocellular carcinoma was 100%, the incidence of nodules had decreased. BrdU positive cells also increased with age, and by week 30 when the incidence of hepatocellular carcinoma was 100%, the number of BrdU-positive cells had decreased. NK cell activity increased until week 10, but at week 20, was less than in the untreated control group. The level of PGE2 increased until week 5, but at week 10, levels were not significantly different from those seen in the untreated control group. On the basis of these results, we concluded that NK activity is closely related to the progression of hepatocarcinogenesis, but PGE2 levels show no significant change. 相似文献
115.
Malignant hyperthermia developed in two Landrace x Large White pigs, 75 and 105 minutes after the induction of anaesthesia with halothane. Rapid treatment and discontinuation of halothane anaesthesia were unable to reverse the condition in the first case but were successful in the second. The delayed onset of malignant hyperthermia after delivery of halothane is unusual and for successful treatment careful monitoring and rapid and aggressive therapy are needed. 相似文献
116.
BACKGROUND: Lymphomas occurring in nasal cavities and paranasal sinuses are uncommon neoplasms in Western, but are reported to be higher in Oriental, countries. A retrospective study was performed to analyze the clinical and pathological characteristics of sinonasal lymphomas/polymorphic reticulosis at Taichung Veterans General Hospital during a 14-year period. METHODS: At Taichung Veterans General Hospital, 37 patients with sinonasal lymphomas (including three patients with polymorphic reticulosis) were seen from November 1982 through September 1996. Excluding three patients without sufficient data, a total of 34 patients with their clinical records were reviewed. Clinical information regarding characteristics of the tumors, histological studies, treatment modalities and follow-up was collected for analysis. RESULTS: The 34 patients who underwent review showed a male-to-female ratio of 2.1:1. Median age was 60 years (range 13-83 years). The most common symptoms were nasal obstruction, nasal discharge/rhinorrhea and epistaxis. Median duration of symptoms at the time of diagnosis was two months. The most frequently involved sites were nasal cavities (right more than left side). There were 31 non-Hodgkin's lymphomas and three polymorphic reticuloses. The pathological classifications revealed 13 diffuse large cell lymphomas, 14 diffuse mixed small and large cell lymphomas and four pleomorphic T-cell lymphomas. Of the 21 adequately staged patients, 13 patients were in stage I; four, stage II; two, stage III and two, stage IV. The immunophenotypic study was performed in 20 patients. Eighteen (90%) of them were T-cell lymphomas and only two cases (10%) derived from B-cell. Though approach to therapy and follow-up periods varied during the time period covered by this study, the differences in survival according to treatment modalities were not statistically significant. The follow-up period ranged from 9 days to 130 months. The mean survival was 84.2 months. The overall five-year survival rate was 63%. CONCLUSIONS: The majority of the cases here were T-cell lymphomas. Most histologic grading by Working formulation belonged to the intermediate grade. Optimal treatment for such a group of patients still has no consensus, but adequate local control is important. If diagnosed and treated early, primary sinonasal lymphomas can be associated with a favorable outcome even with local treatment alone. 相似文献
117.
SA Epstein TH Lin J Audrain M Stefanek B Rimer C Lerman 《Canadian Metallurgical Quarterly》1997,38(3):253-261
The influence of the primary antibody, the fixative, and the antigen unmasking technique on the method sensitivity of immunohistochemistry as a method for the identification of viral hemorrhagic septicemia (VHS) virus in paraffin-embedded specimens of naturally infected rainbow trout (Oncorhynchus mykiss) was examined. Fish (200-300 g) were collected during an outbreak of VHS. Parallel specimens from liver, spleen, kidney, and brain were fixed by immersion in 10% phosphate-buffered formalin, periodate-lysine-paraformaldehyde (PLP), Bouin's fluid, or absolute ethanol. Virus cultivation was also performed on parallel specimens, and the virus titer (TCID50/ml) was determined. Purified nucleocapsid protein (N-protein) of the virus was incorporated in an artificial antigen substrate polymerized bovine serum albumin), fixed as described above, and embedded in paraffin wax. Microwave unmasking was performed on formalin-, PLP-, and Bouin's fluid-fixed specimens. The presence of virus peptides in situ or N-protein in the artificial antigen substrates was visualized using an immunohistochemical method based on alkaline phosphatase or peroxidase and one polyclonal and five monoclonal polypeptide-specific antibodies. VHS virus was identified in situ in specimens with high virus titers (10(7-8) TCID50/ml) regardless of the fixative and without the need of an unmasking procedure. A pronounced masking effect was observed for the cross-linking formalin and PLP fixatives. Regardless of the primary antibodies used, there was a significantly higher epidemiologic sensitivity (the proportion of virus positive samples that tested positive by immunohistochemistry) using ethanol and Bouin's fluid compared with formalin and PLP (P < 0.05). At 10(5) TCID50/ml, the average sensitivity reached 0.5, and at > or = 10(6) TCID50/ml, sensitivity was 0.9. Unmasking procedures showed a moderate effect and did not result in significantly higher epidemiologic sensitivity (P = 0.17), There was great variation for the different monoclonal antibodies/antigens and fixatives. Sensitivity studies on antigen substrates were in accordance with results of in situ studies that showed the highest sensitivity for ethanol and Bouin's fluid. Virus cultivation was more sensitive than immunohistochemistry. This study showed that the fixative and the primary antibody both influence method sensitivity and that VHS virus antigens concealed during fixation are difficult to reexpose. Immunostaining for VHS virus should be performed with monoclonal antibodies specific for the N-protein, and tissue samples should be fixed in either ethanol or Bouin's fluid. Immunohistochemistry is specific but is less sensitive than virus cultivation. Immunostaining for VHS virus can be a valuable supplement to virus cultivation during acute outbreaks of disease. 相似文献
118.
RR Gaiser P Venkateswaren TG Cheek E Persiley J Buxbaum J Hedge TH Joyce BB Gutsche 《Canadian Metallurgical Quarterly》1997,9(7):564-568
STUDY OBJECTIVE: Part 1: To measure ropivacaine levels in the mother and infant at delivery after continuous lumbar epidural infusion. Part 2: To compare epidural ropivacaine to epidural bupivacaine for labor analgesia in regard to effectiveness, motor blockade, and maternal and neonatal effects. DESIGN: Part 1: Open-labelled, non-blind study. Part 2: Randomized, double-blind study. SETTING: Labor and delivery units of two academic hospitals. PATIENTS: Part 1: 20 ASA physical status I and II parturients in active labor. Part 2: 81 ASA physical status I and II parturients in active labor. INTERVENTIONS: For Part 1, 8 to 12 ml of 0.25% ropivacaine was administered through a lumbar epidural catheter to achieve a T10 dermatomal sensory level. An infusion of 0.25% ropivacaine, 8 to 10 ml/hr, maintained this sensory level. Maternal and umbilical cord blood samples obtained at delivery were analyzed for ropivacaine concentration. For Part 2, anesthetic management was similar to that previously described except patients were randomized to receive either 0.25% ropivacaine or 0.25% bupivacaine. Onset, regression, maximal spread of sensory block, and onset and degree of motor blockade were measured. Contraction pain as assessed using a visual analog scale (VAS), maternal blood pressure, and heart rate were determined every 5 minutes until a stable VAS-contraction score was achieved, and every 30 minutes thereafter. Neonatal assessment included Apgar scores and neurologic and adaptive capacity scores (NACS) at 15 minutes, 2 hours, and 24 hours. MEASUREMENTS AND MAIN RESULTS: For Part 1, the total and free maternal arterial concentrations of ropivacaine at delivery were 0.64 +/- 0.14 microgram/ml and 0.10 +/- .02 microgram/ml, respectively; the umbilical venous total and free concentrations were 0.19 +/- 0.03 microgram/ml and 0.12 +/- 0.07 microgram/ml, respectively (n = 12). The umbilical arterial and venous concentrations did not differ for both the free and total concentrations. For Part 2, there was no difference between ropivacaine and bupivacaine in the variables measured. Umbilical cord gases and Apgar scores were not different between the two groups; NACS were higher at 15 minutes and 2 hours in the ropivacaine group (p < 0.05) than the bupivacaine group. CONCLUSION: Both ropivacaine and bupivacaine produced excellent analgesia for labor with no major adverse effect on the mother or neonate. 相似文献
119.
Data on the outcomes of more than 15,000 pregnancies originating between May 1966 and February 1969 were analyzed. The accuracy of the data was evaluated, rates of induced abortion and stillbirth were reported, and the demographic effect of induced abortion was estimated. The demographic effect was defined as the percentage increase in fertility that would have occurred in the absence of induced abortion, assuming no compensating change in alternative fertility control practices. Our principal findings were as follows: 1. We were unable to determine the completeness with which induced abortion was reported in the Registration Study. During the three years covered by the study, rates of induced abortion increased by 54 percent, reflecting a trend in the incidence or in the reporting of events or in both. We concluded that, in any case, the data for the final year of the study, 1968, were more complete than for the earlier two years. 2. Age-specific rates of induced abortion for 1968 displayed a strong urban-rural gradient, being much higher in the city areas than in the rural areas. Within each urban--rural stratum, the rates increases monotonically with age and reached maximum values in the age group 40 and older (553, 436, and 374 per 1,000 pregnancies for city, urban, and rural areas, respectively). 3. Estimates of the demographic effect indicated that, in the absence of induced abortion, the TFR for all Taiwan would have been 12 percent higher in 1968. Under the same assumption, it was estimated that the TFR would have been higher by 16 percent in city areas, 11 percent in urban areas, and 9 percent in rural areas. This urbanization gradient implies that induced abortion contributed to urban-rural fertility differentials. We estimated that about one-third of those differentials were due to induced abortion. 4. Estimates of the demographic effect were also made after adjusting the rates of induced abortion for an assumed level of underreporting of 50 percent. The adjusted estimate of the demographic effect for all Taiwan in 1968 was 19 percent. 相似文献
120.