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L M Chen

Publications and source records attributed to L M Chen.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Determination of impurities in electrolytic manganese by atomic absorption spectrometry].

The content of K, Na, Ca, Mg, Fe in electrolytic manganese are determined by FAAS, and content of Cu, Cr, Co, Ni determined by GFAAS after sample is dissolved by HCl (aq). The best condition for determination is investigated, including method of dissolving and acidity, and influence of coexist elements and exclusion of these influences. The methods prove to be rapid, accurate and convenient. The recoveries of method are 88.9%-108.7%, the relative standard deviations are 0.6%-6.7%. The results obtained by calibration curve method are in good conformity with the standard addition method and results measured by ICP. The method can be utilized in analysis of impurities in electrolytic manganese.

Chromium↗
PubMed2000

Developmental control of endocytosis in dendritic cells by Cdc42.

Dendritic cells (DCs) developmentally regulate antigen uptake by controlling their endocytic capacity. Immature DCs actively internalize antigen. However, mature DCs are poorly endocytic, functioning instead to present antigens to T cells. We have found that endocytic downregulation reflects a decrease in endocytic activity controlled by Rho family GTPases, especially Cdc42. Blocking Cdc42 function by Toxin B treatment or injection of dominant-negative inhibitors of Cdc42 abrogates endocytosis in immature DCs. In mature DCs, injection of constitutively active Cdc42 or microbial delivery of a Cdc42 nucleotide exchange factor reactivates endocytosis. DCs regulate endogenous levels of Cdc42-GTP with activated Cdc42 detectable only in immature cells. We conclude that DCs developmentally regulate endocytosis at least in part by controlling levels of activated Cdc42.

Animals↗
PubMed2000

Association of beta 1 integrin with focal adhesion kinase and paxillin in differentiating Schwann cells.

Schwann cells (SCs) differentiate into a myelinating cell when simultaneously adhering to an axon destined for myelination and basal lamina. We are interested in defining the signaling pathway activated by basal lamina. Using SC/sensory neuron (N) cocultures, we identified beta1 integrin and F-actin as components of a pathway leading to myelin gene expression and myelination (Fernandez-Valle et al., 1994, 1997). Here, we show that focal adhesion kinase (FAK) and paxillin are constitutively expressed by SCs contacting axons in the absence of basal lamina. Tyrosine phosphorylation of FAK and paxillin increases as SCs form basal lamina and differentiate. FAK and paxillin specifically coimmunoprecipitate with beta1 integrin in differentiating SC/N cocultures but not SC-only cultures. Paxillin coimmunoprecipitates with FAK and fyn kinase in differentiating SC/N cocultures. A subset of tyrosine-phosphorylated beta1 integrin, FAK, and paxillin molecules reside in the insoluble, F-actin-rich fraction of differentiating cocultures. Cytochalasin D, an actin depolymerizing agent, decreases tyrosine phosphorylation of FAK and paxillin and their association with beta1 integrin and causes a dose-dependent increase in the abundance of insoluble FAK and paxillin complexes. Collectively, our work indicates that beta1 integrin, FAK, paxillin, and fyn kinase form an actin-associated complex in SCs adhering to basal lamina in the presence of axons. This complex may be important for initiating the process of SC differentiation into a myelinating cell.

Animals↗
PubMed2000

New scoring system identifies kidney outcome with radiation therapy in acute renal allograft rejection.

PURPOSE: To evaluate the role of radiation therapy for acute refractory renal rejection after failure of medical intervention, and to identify risk factors that influence graft survival following radiation therapy. METHODS: Between June 1989 and December 1995, 53 renal transplant recipients (34 men and 19 women) were treated with localized radiation therapy for acute renal allograft rejection. Graft rejection was defined as an increase in serum creatinine with histologic evidence of rejection on renal biopsy. Ninety-one percent were cadaveric transplant recipients. The majority of patients who experienced acute graft rejection initially received corticosteroid therapy, except for 25% who were referred for radiation therapy and steroids for the first rejection. In more recent years, patients with moderate or severe steroid-resistant or recurrent rejection received OKT3, a polyclonal antilymphocyte antibody (ATGAM), tacrolimus (FK506), or mycophenolate mofetil (MMF). Patients who failed to respond to medical treatment were then referred for radiation therapy. Ultrasound was performed for kidney localization. Treatment consisted of a dose of 600 cGy given in 3 or 4 fractions using 6 MV photons, delivered AP or AP/PA. RESULTS: The overall actuarial graft survival from the initiation of RT was 83% at 1 month, 60% at 1 year, and 36% at 5 years. The median follow-up from the date of transplant to the last follow-up was 22 months. The median time from the date of transplant to the initiation of radiotherapy was 3 months, and the median time from the initiation of radiotherapy to the last follow-up was 10 months. Variables evaluated were as follows: human leukocyte antigen matching on HLA-A, HLA-B, and HLA-DR, the transplant panel-reactive antibodies (PRA) at transplantation, number of acute rejection episodes, interval from the date of the transplant to the first rejection, serum creatinine levels at the time of the first radiation treatment, number of transplants, and concomitant immunosuppressive therapy. Independent factors examined by Cox regression modeling were: gender (p = 0.005), creatinine levels (p = 0.000), HLA-DR (p70% (p = 0.014). Each factor was scored using integral coefficients to generate four different groups. The Kaplan-Meier survival analyzed by group produces an interpretable separation of the risk factors for graft loss. CONCLUSIONS: The outcome in patients treated with radiation therapy for acute renal graft rejection can be predicted by a novel scoring system. Patients with scores of three or less are able to achieve 100% renal graft salvage, while patients who have scores of 12 or higher are not able to be salvaged with the current radiation therapy regimen. Future studies should be directed toward identifying more effective treatment for patients who have a high score based on our criteria. The scoring system should be utilized to identify patients at risk who could benefit from radiation therapy. Further study with a randomized trial utilizing this scoring system is needed to confirm the validity of the scoring system in predicting graft survival and the efficacy of radiation in patients who receive radiation therapy for acute graft rejection.

Acute Disease↗
PubMed2000

Splenectomy and surgical cytoreduction for ovarian cancer.

OBJECTIVE: The aim of this study was to evaluate the role of splenectomy, as a surrogate marker for aggressive tumor cytoreduction in ovarian cancer, and its impact on patient morbidity and survival. METHODS: A retrospective cohort study of 35 patients who underwent splenectomy for ovarian cancer cytoreduction between August 1986 and May 1998 was performed. Data abstracted from the medical record included patient demographics, preoperative imaging, surgical procedures, tumor distribution, postoperative complications, chemotherapy treatment, and follow-up information. RESULTS: Splenectomy was performed in 13 patients at the time of primary cytoreduction and in 22 patients at the time of secondary cytoreduction. Preoperative diagnosis of splenic involvement was frequently made prior to secondary surgery, 77.3% compared to 15.4% of primary cases. In addition, parenchymal splenic involvement was more commonly observed at recurrence, 59.1% vs 23.1% at initial presentation. Disease distribution in secondary cytoreduction cases tended to be more focal, macronodular, and have no ascites. Cytoreduction to less than 1 cm disease was achieved in 100% of primary patients and 86% of secondary patients. Major morbidity (pneumonia, PE, sepsis, pancreatitis, MI) occurred in 23.1% of primary patients and 28.6% of secondary patients. Combining splenectomy with other cytoreductive procedures may make splenectomy itself seem more morbid. With a 17-month median follow-up, median progression-free interval was 24 months in primary patients and 14 months in secondary patients. Among secondary patients, median survival time after splenectomy and cytoreduction was 41 months. CONCLUSIONS: Splenectomy at the time of primary and secondary cytoreduction for ovarian cancer can be performed with acceptable morbidity. Secondary cytoreduction patients may be selected preoperatively by their progression-free interval, prior degree of cytoreduction, and macronodular tumor involvement on imaging studies. Identification of splenic involvement allows for appropriate counseling and preoperative preparation.

Adult↗
PubMed2000

Posterior cruciate ligament and coupled posterolateral instability of the knee.

We wanted to investigate the role of the posterior cruciate ligament (PCL) in the knee's posterolateral stability and the magnitude of the coupled posterolateral instability with the knee examined at 90 degrees of flexion. The coupled posterolateral instability of the knee was studied by selective ligament cutting in cadaver knees set at 90 degrees. The coupled posterolateral displacement after cutting the PCL was 173% of the intact knee. With an intact PCL, the coupled posterolateral displacement after cutting the popliteus tendon and lateral collateral ligament with the knee at 90 degrees of flexion was 299% of the intact knee. When the PCL was cut together with the popliteus tendon and lateral collateral ligament, the coupled posterolateral displacement was 367%. The PCL plays an important role in the posterolateral stability of the knee, and its injury may cause mild (< 5 mm) to moderate (5-10 mm) posterolateral instability. Thus, in a knee with posterolateral instability, injury of the PCL must be considered. With an intact PCL, the posterolateral instability was very recognizable with the knee at 90 degrees of flexion, and injury to the PCL further increased the posterolateral instability and caused posterior translation of the knee. Therefore, examination for posterolateral instability of the knee should also be performed with the knee at 90 degrees of flexion, which is much easier to perform in a clinical setting. A positive posterior translation rather than posterolateral instability at different knee positions differentiates knees with combined PCL and posterolateral instability from knees with isolated posterolateral instability.

Cadaver↗
PubMed2000

Image analysis and flow cytometric DNA studies of benign and malignant body cavity fluids: reappraisal of the role of current methods in the differential diagnosis of reactive versus malignant conditions.

Cytologic examination of body fluids is commonly performed in the clinical laboratory. Determination of the presence of malignancy may sometimes be difficult. In this study, we prospectively studied 60 body fluids with a panel of antibodies, including MOC-31, epithelial membrane antigen, carcinoembryonic antigen, B72.3, keratin, desmin, and CA-125. DNA and S-phase studies were performed both by flow cytometry and image analysis. Thirty-seven fluids were classified as benign and 23 were classified as malignant. The sensitivity of the antibodies for identification of carcinoma in descending order of percentage detection rate were MOC-31 (95%), epithelial membrane antigen (93%), B72.3 (84%), and carcinoembryonic antigen (80%). Desmin stained mesothelial cells in all cases. CA-125 gave similar results but was less specific. Flow cytometry detected 14 of 20 malignant fluids and image analysis 17 of 23 by identifying an aneuploid population. Benign reactive mesothelial cells were not aneuploid. Tetraploidy due to reactive mesothelial cells was found in 9 of 37 body fluids. Their S-phase fraction was low (average, 3.2%). Tetraploidy in malignant cells was distinguished from the reactive mesothelial cells by high S-phase (average, 25.95). S-phase had some use as a discriminating factor, because no benign reactive cases had more than 17%. However, 7 of 23 malignant cases had a value below 17%. DNA analysis by image was more sensitive and specific than flow. Either may be used when immunocytochemistry is nondiagnostic or cannot be performed.

Adult↗
PubMed2000

Analysis of the role of adjuvant chemotherapy for invasive carcinoma of the esophagus.

The purpose of this report is to analyze the role and optimum integration of chemotherapy for invasive carcinoma of the esophagus in the combined modality setting. The charts of 157 patients with primary invasive nonmetastatic carcinoma of the esophagus treated with curative intent between 1984 and 1998 were reviewed. Various combinations of chemotherapy (C), radiotherapy (R), and surgery (S) were used. Chemotherapy was multiagent (typically 5-fluorouracil [5-FU]/cisplatin/hydroxyurea, 5-FU/cisplatin/leucovorin, or docetaxel/cisplatin) for all but seven patients treated with single agents. The clinical endpoints examined were overall survival (OS) and cause-specific survival (CSS). Multivariate analyses and pairwise comparisons were made for determination of the benefit of chemotherapy. On the multivariate analyses, only American Joint Committee on Cancer stage and chemotherapy were statistically significant determinants of both OS and CSS. Following are the results of the pairwise analyses: 3-year OS: (no C) versus (any C): 16% versus 27% (p = 0.02); (S) versus (C+S): 19% versus 34% (p = 0.35); (R) versus (C+R): 0% versus 13% (p = 0.05); (R + S) versus (C + R + S): 18% versus 33% (p = 0.03). The administration of adjuvant chemotherapy can improve survival in patients with invasive nonmetastatic esophageal carcinoma. This benefit appears to be greater when chemotherapy is given with radiotherapy (with or without surgery) than in the absence of radiotherapy, perhaps because of a radiosensitizing effect not possible when using surgery is the only local control modality.

Adenocarcinoma↗
PubMed2000

Virus infection in patients with histiocytic necrotizing lymphadenitis in Taiwan. Detection of Epstein-Barr virus, type I human T-cell lymphotropic virus, and parvovirus B19.

The relationship of Epstein-Barr virus (EBV), type I human T-cell lymphotropic virus (HTLV-I), and parvovirus B19 to histiocytic necrotizing lymphadenitis was studied prospectively in 10 Taiwanese patients using materials obtained by fine-needle aspiration and lymph node biopsy. The presence of EBV was detected by in situ hybridization for EBV-encoded RNA expression. Immunocytochemistry was used to detect virus-encoded protein for EBV and parvovirus B19. DNA in situ hybridization and polymerase chain reaction were performed to determine the existence of HTLV-I provirus. Expressions of EBV-encoded RNA and Fas ligand were detected in all cases. Expression of EBV-encoded protein was identified in only 1 case. Neither HTLV-I nor parvovirus B19 was detected in any case.

Adolescent↗
PubMed2000

Treatment of painful heels using extracorporeal shock wave.

BACKGROUND AND PURPOSE: Shock wave therapy has been shown to improve many tendinopathies at the tendon-bone junction. The purpose of this study was to investigate the safety and effectiveness of extracorporeal shock wave therapy for the treatment of painful heels. METHODS: Sixty-six patients, including 45 women and 21 men with an average age of 47.70 years (range, 19-75 years), were included in the study. Each patient received 1,000 impulses of shock waves at a 14-kV generator voltage at the affected site under local anesthesia. Twelve patients received a second treatment, and two patients received a third treatment. RESULTS: Of 58 patients with 6 weeks' follow-up, five (9%) were complaint-free, 21 (37%) were significantly better, 27 (47%) were slightly better, and five (9%) were unchanged. Of 41 patients with 12 weeks' follow-up, 11 (27%) were complaint-free, 22 (54%) were significantly better, seven (17%) were slightly better, and one (2%) was unchanged. The results at 12 weeks were much better than those at 6 weeks. The effect of shock waves on painful heels continued between 6 and 12 weeks. Twelve patients who did not respond favorably to the first treatment showed significantly better results after a second treatment. Two patients who had a third treatment also achieved satisfactory results. There were no device-related problems or systemic or local complications. CONCLUSIONS: Extracorporeal shock wave therapy is a new modality that is safe and effective in the treatment of painful heel spurs.

Adolescent↗
PubMed2000

Deep vein thrombosis after total knee arthroplasty.

BACKGROUND AND PURPOSE: The incidence of deep vein thrombosis (DVT) after total knee arthroplasty (TKA) in the Asian population is probably higher than is commonly assumed by clinicians. The purpose of this study was to investigate the incidence of DVT after TKA in a southern Taiwanese population and to determine whether routine prophylaxis against DVT is indicated. MATERIALS AND METHODS: The incidence of DVT was investigated in 107 ascending venograms performed in 105 knees in 102 patients after TKA. Observations were made and interpreted by orthopedic radiologists blinded to the clinical condition of the patients. The correlation of DVT with the medical conditions, anesthesia type, and local physical findings were analyzed. RESULTS: The overall incidence of DVT after TKA was 63.6% (68/107); 95.6% (63/68) of cases involved the distal veins in the calf and only 4.4% (3/68) involved the proximal vein at the popliteal level. There was no higher incidence of thrombosis in the femoral and iliac veins, and no pulmonary embolism. Approximately 70% of patients with DVT were symptomatic and required treatment. There was no statistically significant correlation of DVT with medical condition, including diabetes mellitus, hypertension, body weight, varicosity, history of thromboembolic disorder and congestive heart failure, or the type of anesthesia or bone cement used. There was a positive correlation of DVT with local physical findings including calf girth enlargement, leg edema, and skin discoloration, and a negative correlation with findings including Homans' sign, cord induration, venous engorgement, and knee effusion. CONCLUSION: The incidence of DVT after TKA in this southern Taiwanese cohort was similar to that in Western populations, and higher than is commonly assumed by clinicians at this facility. However, the rate of proximal thrombosis and pulmonary embolism was much lower than in previous studies from Western populations. The majority of cases of DVT involved the veins in the calf; approximately 70% of patients were symptomatic and required treatment.

Aged↗
PubMed1999

Ex vivo expansion of autologous bone marrow CD34(+) cells with porcine microvascular endothelial cells results in a graft capable of rescuing lethally irradiated baboons.

Hematopoietic stem cell (HSC) self-renewal in vitro has been reported to result in a diminished proliferative capacity or acquisition of a homing defect that might compromise marrow repopulation. Our group has demonstrated that human HSC expanded ex vivo in the presence of porcine microvascular endothelial cells (PMVEC) retain the capacity to competitively repopulate human bone fragments implanted in severe combined immunodeficiency (SCID) mice. To further test the marrow repopulating capacity of expanded stem cells, our laboratory has established a myeloablative, fractionated total body irradiation conditioning protocol for autologous marrow transplantation in baboons. A control animal, which received no transplant, as well as two animals, which received a suboptimal number of marrow mononuclear cells, died 37, 43, and 59 days postirradiation, respectively. Immunomagnetically selected CD34(+) marrow cells from two baboons were placed in PMVEC coculture with exogenous human cytokines. After 10 days of expansion, the grafts represented a 14-fold to 22-fold increase in cell number, a 4-fold to 5-fold expansion of CD34(+) cells, a 3-fold to 4-fold increase of colony-forming unit-granulocyte-macrophage (CFU-GM), and a 12-fold to 17-fold increase of cobblestone area-forming cells (CAFC) over input. Both baboons became transfusion independent by day 23 posttransplant and achieved absolute neutrophil count (ANC) >500/microL by day 25 +/- 1 and platelets >20,000/microL by day 29 +/- 2. This hematopoietic recovery was delayed in comparison to two animals that received either a graft consisting of freshly isolated, unexpanded CD34(+) cells or 175 x 10(6)/kg unfractionated marrow mononuclear cells. Analysis of the proliferative status of cells in PMVEC expansion cultures demonstrated that by 10 days, 99.8% of CD34(+) cells present in the cultures had undergone cycling, and that the population of cells expressing a CD34(+) CD38(-) phenotype in the cultures was also the result of active cell division. These data indicate that isolated bone marrow CD34(+) cells may undergo cell division during ex vivo expansion in the presence of endothelial cells to provide a graft capable of rescuing a myeloablated autologous host.

Animals↗
PubMed1999

Requirement of p21-activated kinase (PAK) for Salmonella typhimurium-induced nuclear responses.

Salmonella typhimurium has sustained a long-standing association with its host and therefore has evolved sophisticated strategies to multiply and survive within this environment. Central to Salmonella pathogenesis is the function of a dedicated type III secretion system that delivers bacterial effector proteins into the host cell cytoplasm. These effectors stimulate nuclear responses and actin cytoskeleton reorganization leading to the production of proinflammatory cytokines and bacterial internalization. The stimulation of these responses requires the function of Cdc42, a member of the Rho family of small molecular weight GTPases, and SopE, a bacterial effector protein that stimulates guanine nucleotide exchange on Rho GTPases. However, nothing is known about the role of Cdc42 effector proteins in S. typhimurium-induced responses. We showed here that S. typhimurium infection of cultured epithelial cells results in the activation of p21-activated kinase (PAK), a serine/threonine kinase that is an effector of Cdc42-dependent responses. Transient expression of a kinase-defective PAK blocked both S. typhimurium- and SopE-induced c-Jun NH2-terminal kinase (JNK) activation but did not interfere with bacteria-induced actin cytoskeleton rearrangements. Similarly, expression of SH3-binding mutants of PAK did not block actin-mediated S. typhimurium entry into cultured cells. However, expression of an effector loop mutant of Cdc42Hs (Cdc42HsC40) unable to bind PAK and other CRIB (for Cdc42/Rac interacting binding)-containing target proteins resulted in abrogation of both S. typhimurium-induced nuclear and cytoskeletal responses. These results show that PAK kinase activity is required for bacteria-induced nuclear responses but it is not required for cytoskeletal rearrangements, indicating that S. typhimurium stimulates cellular responses through different Cdc42 downstream effector activities. In addition, these results demonstrate that the effector loop of Cdc42 implicated in the binding of PAK and other CRIB-containing target proteins is required for both responses.

Animals↗
PubMed1999

Results of a phase II concurrent chemoradiotherapy study using three-dimensional conformal radiotherapy with cisplatin and oral etoposide in stage III nonsmall-cell lung cancer.

This phase II study was designed to utilize conformal radiation therapy with cisplatin and oral etoposide in patients with stage III or locally recurrent non-small-cell lung cancer to determine tolerance and toxicity of therapy. From April 1992-February 1996, 18 patients with pathologically confirmed stage IIIA, IIIB, or locally recurrent non-small-cell lung cancer (NSCLC) were entered on study. Metastatic workup included a CT scan of the thorax and upper abdomen as well as a bone scan. Chemotherapy consisted of IV cisplatin (100 mg/m2) with IV etoposide (25 mg/m2) on day 1; oral etoposide was given (50 mg/m2) days 2-14. Using three-dimensional planning, 40-45 Gy were delivered to the clinical target volume, followed by a boost to the gross tumor volume for a total of 70 Gy. Patients with recurrent disease received 40-50 Gy in total. Eighteen patients were enrolled: 16 patients were treated with curative intent and were evaluable for outcome. Two patients were treated for locally recurrent NSCLC and were not included in the outcome analysis. Stages included IIIA (44%) and stage IIIB (54%). Forty-four percent had T3/4 tumors, and 69% had N2/3 disease. Overall survival at 1 year was 64%, while 2-year overall survival was 50%. Distant metastasis-free survival at 1 year was 67%, and at 2 years 60%. The 1-year chest progression-free survival was 57%, and at 2 years 50%. Sixty-three percent required hospitalization for dehydration or neutropenia. Fifty-six percent developed leukopenia (<1,000 cells/microl) sometime during the therapy. We conclude that concurrent cisplatin and oral etoposide with conformal radiation therapy provide encouraging results in stage III lung cancer. The major toxicities of this therapy included leukopenia, thrombocytopenia, and mucosal esophagitis. Local progression of disease continues to be a problem with the current doses given. Future studies should evaluate dose escalation of radiation therapy with limited volumes, utilizing conformal radiation and chemotherapy to improve local control and potentially impact upon distant metastases.

Administration, Oral↗
PubMed1999

Molecular characterization of germline mutations in the BRCA1 and BRCA2 genes from breast cancer families in Taiwan.

A total of 18 families with multiple cases of breast cancer were identified from southern Taiwan, and 5 of these families were found to carry cancer-associated germline mutations in the BRCA1 and BRCA2 genes. One novel cryptic splicing mutation of the BRCA1 gene, found in two unrelated families, was shown to be a deletion of 10 bp near the branch site in intron 7. This mutation causes an insertion of 59 nucleotides derived from intron 7 and results in a frameshift, leading to premature translational termination of BRCA1 mRNA in exon 8. Deletions of 2670delC, 3073delT and 6696-7delTC in the BRCA2 gene were found in three other breast cancer families. All three deletions are predicted to generate frameshifts and to result in the premature termination of BRCA2 protein translation. Several genetic polymorphisms in both BRCA1 and BRCA2 genes were also detected in this investigation.

Adult↗
PubMed1999

Interobserver variability in data collection of the APACHE II score in teaching and community hospitals.

OBJECTIVES: To examine interobserver reliability of the Acute Physiologic and Chronic Health Evaluation (APACHE) II score and identify major causes of variability in data collection. DESIGN: Descriptive, comparative analysis. SETTING: Nine intensive care units in two teaching and six community hospitals SUBJECTS: A random sample of 342 patient records selected from a network database. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Data were reabstracted and compared with the original records. Individual physiologic points derived from the APACHE II scoring system (instead of the actual physiologic values) were compared using the kappa statistic. Paired measurements of the continuous variables were compared using the interclass correlation coefficient and Bland-Altman plots. Excellent agreement was found in most demographic, admission, and discharge data. The system failure requiring intensive care unit admission was consistently identified by both data collectors in 88% of cases, but only 66% agreed on the exact admitting diagnosis. For APACHE II score components, the kappa statistic ranged from 0.315 for the Glasgow Coma Scale point to 0.976 for the age point. Significant disagreement regarding the probability of death derived from the APACHE II model was evident in some patient records. Overall agreement among groups of patients regarding the APACHE II score was good, however, with no significant difference in the mean score (20.2 vs. 20.1; p = .758). The predicted mortality from the reabstracted data was 30%, similar to the 27% predicted mortality from the original data (p = .380). CONCLUSION: Reliability of data collection varied widely in different components of the APACHE II probability-of-death model. Significant discrepancies in some components suggested a lack of explicit definitions and timing for consistent data collection between institutions or between data collectors. Nonetheless, variability resulting from data collection appears to be randomly distributed, so that comparisons of group means are valid.

APACHE↗
PubMed1999

Bioequivalence evaluation of two sertraline tablet formulations in healthy male volunteers after a single dose administration.

SUBJECTS, MATERIAL AND METHODS: According to a randomized two-period crossover design, 12 Chinese male volunteers were treated with 2 sertraline tablet formulations, one was made in China as test tablet, the other was made in England as reference tablet. Each volunteer received each sertraline in a single dose of 150 mg. The 2 medications were carried out by a wash-out phase of 23 days. Blood samples were obtained just before dosing and at 10 time points until 96 hours after administration, and plasma sertraline concentrations were determined by a sensitive gas-chromagraphy electron-capture method with a lower limit of quantification of 0.625 ng/ml. The bioequivalence of 2 formulations was evaluated by the shortest 90% confidence interval method which corresponds to the two one-sided test method. RESULTS: The point estimate (90% confidence interval) of the mean ratio (test/reference) for AUC(0-96) was 97.19% (82.66% to 122.33%), for Cmax 96.27% (83.64% to 121.36%), and for t(l/2) 96.31% (85.43% to 119.57%). Regarding Tmax (test-reference), the 90% confidence interval ranged from -4 to +4 hours, but the difference between the Tmax values of 2 products is clinically of minor importance. CONCLUSION: Therefore, it can be concluded that 2 sertraline tablet formulations are bioequivalent. administration, sertraline is slowly absorbed with peak plasma concentrations at 6 - 8 h, and has a terminal elimination half-life of approximately 26 h, indicating once-daily dosing is available. Clinically, it can be taken either in the morning or in the evening, with or without food [Ronfeld et al. 1997b]. In addition, it also exhibits higher plasma protein binding up to 97% and extensive first-pass metabolism. By demethylation, sertraline is metabolized primarily to N-demethylsertraline, and then eliminated by hydroxylation arid conjugation [Tremaine et al. 1989]. This study aimed at assessing of bioequivalence of two sertraline formulations (produced in China and England, respectively) in healthy male volunteers after a single dose administration.

Adult↗