Pharmacokinetic and bioequivalence studies of ibuprofen suspension after a single-dose administration in healthy Chinese volunteers

OBJECTIVE

The aim of this study was to assessed the pharmacokinetic and bioequivalence of 2 formulations of ibuprofen suspension.

METHOD

20 healthy volunteers were enrolled into this random, single-dose, 2-way crossover, open-label, single-centre, pharmacokinetic study. After overnight fasting, 2 formulations (test and reference) of ibuprofen (400 mg ibuprofen/20 mL suspension) were administered as a single dose on 2 treatment days separated by a 7-day washout period. After dosing, blood samples were drawn for a period of 12 h. The plasma samples were analyzed for the presence of ibuprofen by HPLC with ultraviolet detection. Pharmacokinetic parameters were determined from plasma concentrations for both formulations.

RESULTS

The main pharmacokinetics parameters of test and reference were as follows: t1/2 was (1.94±0.38) h and (1.95±0.28) h; Cmax was (33.41±7.83) μg · mL- 1 and (31.08±9.30) μg · mL- 1; AUC0-12 was (91.44±19.26) μg · mL-1 · h and (84.75±24.45) μg · mL-1 · h; AUC0-∞ was (92.82±19.94) μg · mL-1 · h and (85.97±24.99) μg · mL-1 · h; median Tmax was 0.5 h (range, 0.25, 2) and 0.5 h (range, 0.25, 1.5). The 90% confidence intervals of the test/reference treatment ratios for Cmax, AUC0-12 and AUC0-∞ were observed to be within the predetermined acceptable interval of 80-125%.

CONCLUSION

This single-dose study in healthy Chinese fasted volunteers was shown that the ibuprofen test and reference met the requirement of the State Food and Drug Administration, and the test and reference were bioequivalent.

A more rapid, sensitive, and specific HPLC-MS/MS method for nifedipine analysis in human plasma and application to a pharmacokinetic study

A more rapid, sensitive and specific high-performance liquid chromatography coupled to -tandem mass spectrometry (HPLC-MS/MS) was developed and validated for the quantification of nifedipine in human plasma, and applied to the pharmacokinetic study of nifedipine in Chinese healthy volunteers. Nifedipine and internal standard (IS) acetaminophen in plasma were extracted with ethyl acetate, separated on a C18 (150 mm×4.6 mm, 5 µm) reversed-phase column, eluted with acetonitrile mixed with 5 mM ammonium acetate solution (pH=6.62) (60:40, v/v), ionized by negative ion pneumatically assisted electrospray and detected in the multi-reaction monitoring mode using precursor→product ions of m/z 354.1→222.2 for nifedipine and 150.1→107.1 for the IS. A single oral dose of 20 mg nifedipine sustained release tablets and blood samples (4 mL) was collected before and 1, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 8, 12, 24, and 36 h after administration. The main pharmacokinetic parameters of nifedipine, as Tmax, t1/2α, t1/2β, t1/2z, Cmax, AUC0~36, AUC0~∞ were 2.80±0.50 h, 6.78±2.52 h, 6.82±2.53 h, 6.69±2.22 h, 76.69±19.51 (ng/mL), 546.49±162.28 (ng · h/mL) and 564.05±176.74 (ng · h/mL), respectively. The calibration curve was linear over the concentration range of 0.17-102 ng/mL (r2>0.99, n=5) with a lower limit of quantification (LLOQ) of 0.17 ng/mL. The intra- and inter-day precision was less than 15% for all quality control samples at concentrations of 0.42, 6.53 and 81.60 ng/mL and the accuracy (relative error, RE) was - 3.92% to 7.31% at 3 quality control levels. The specificity, matrix effect, recovery, sensitivity, linearity, accuracy, precision and stabilities were validated, and can fulfill the requirement of pharmacokinetic study of nifedipine sustained release tablets in Chinese volunteers.

Effects of degradable MG-ND-ZN-ZR alloy on osteoblastic cell function

This study aimed to investigate the effects of a novel patented Mg-3Nd-0.2Zn-0.4Zr (weight %, JDBM) alloy on osteoblastic cell function, as these cells play an important role in bone repair and remodeling. The associated effects of the JDBM alloy on osteoblastic cell function involving cell adhesion, cell proliferation, and mineralization were investigated using scanning electron microscopy (SEM), MTT assay and ambramycin staining, respectively. At the same time, the in vitro degradation behavior of the JDBM alloy in cell culture medium was evaluated by the weight-loss method and SEM. Pure magnesium was used as control. The results showed that osteoblastic cells cultured on JDBM alloy samples manifested better cell adhesion, improved cell proliferation and increased mineralization ability, compared with cells seeded on pure magnesium samples. Our data indicate that the JDBM alloy has excellent bioactivity, improving the cell function of osteoblastic cells seeded on it.

Pharmacokinetics of ginkgolide B injection in beagle dogs

A liquid chromatography-mass spectrometry method was developed, validated, and applied to the pharmacokinetic study with doses of 0.68, 2.73 and 10.92 mg/kg of ginkgolide B in beagle dogs after intravenous infusion.An aliquot of blood samples were -collected, separated and quantitatively analyzed by liquid chromatography-mass spectrometry method with mobile phase of acetonitrile-0.02% ammonia solution (33:67, v/v) at a flow rate of 0.8 mL/min on the UltimateTM XB-C18 column (5 μm, 4.6×150 mm).The method was sensitive, accurate and convenient, and can be used for the determination of ginkgolide B in beagle dogs. The Cmax and AUC0-∞ of GB increased with dose escalation, but ANOVA analyses showed that no significant difference was observed in other pharmacokinetic parameters between different doses.An LC/MS method was developed with good sensitivity, reproducibility and specificity. In the pharmacokinetic study of GB in beagle dogs, linear pharmacokinetics was found at doses from 0.62 to 10.92 mg/kg after a single-dose intravenous infusion. Gender differences were not observed in the pharmacokinetics of GB.

Measurement of the proton-air cross section at √s=57 TeV with the Pierre Auger Observatory

We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505±22(stat)(-36)(+28)(syst)] mb is found.

BMP activity is required for tooth development from the lamina to bud stage

Several Bmp genes are expressed in the developing mouse tooth germ from the initiation to the late-differentiation stages, and play pivotal roles in multiple steps of tooth development. In this study, we investigated the requirement of BMP activity in early tooth development by transgenic overexpression of the extracellular BMP antagonist Noggin. We show that overexpression of Noggin in the dental epithelium at the tooth initiation stage arrests tooth development at the lamina/early-bud stage. This phenotype is coupled with a significantly reduced level of cell proliferation rate and a down-regulation of Cyclin-D1 expression, specifically in the dental epithelium. Despite unaltered expression of genes known to be implicated in early tooth development in the dental mesenchyme and dental epithelium of transgenic embryos, the expression of Pitx2, a molecular marker for the dental epithelium, became down-regulated, suggesting the loss of odontogenic fate in the transgenic dental epithelium. Our results reveal a novel role for BMP signaling in the progression of tooth development from the lamina stage to the bud stage by regulating cell proliferation and by maintaining odontogenic fate of the dental epithelium.

Polymorphism of HMGA1 is associated with increased risk of type 2 diabetes among Chinese individuals

AIMS/HYPOTHESIS

Variants of the high-mobility group A1 (HMGA1) gene have been shown to be associated with insulin resistance and type 2 diabetes in individuals of European origin. We aimed to determine whether this locus confers significant susceptibility to type 2 diabetes in the Han Chinese population, and thus cross-race susceptibility to type 2 diabetes.

METHODS

Polymorphisms in HMGA1 were identified by direct sequencing of genomic DNA derived from 192 Chinese participants (96 patients with type 2 diabetes and 96 controls). We then genotyped the common variant IVS5-13insC (c.136-14_136-13insC) in two other independent cohorts, including a total of 2,533 cases and 2,643 ethnically matched controls.

RESULTS

We confirmed the association of the HMGA1 variant IVS5-13insC (c.136-14_136-13insC) with type 2 diabetes with an OR of 1.34 (95% CI 1.15, 1.56, p = 0.0002 under a dominant model, and 95% CI 1.16, 1.55, p = 0.0002 under an additive model) in the Han Chinese population, corresponding to a population attributable risk fraction of 5.0%.

CONCLUSIONS/INTERPRETATION

HMGA1 is an important susceptibility locus that confers a high cross-race risk of the development of type 2 diabetes.

Determination of norcantharidin in mouse tissues by liquid chromatography coupled to tandem mass spectrometry and its tissue distribution study

The purpose of this study is to determine the concentrations of norcantharidin (CAS NO: 5442-12-6) in mouse tissues and investigate its tissue distribution after intragastric administration of disodium norcantharidate solution. A highly sensitive and specific liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated, using ribavirin (CAS NO: 36791-04-5) as the internal standard (IS). Norcantharidin and IS were extracted from 0.3 mL tissue homogenates using protein precipitation with acetone under acid condition. The analyte was separated on a C18 reverse phase column and analyzed by MS/MS in the multiple reaction monitoring (MRM) mode using ESI with positive ionization, m/z 169→123 for norcantharidin and m/z 267→135 for IS. The developed method was validated over a linear range of concentrations 0.01~5 μg·mL - 1 in liver, lung, kidney, stomach, small intestine, uterus and testis, 0.005~0.5 μg·mL - 1 in heart, spleen and brain, the correlation coefficients (r2) were between 0.9918 and 0.9976. The tissue distribution study result was as follows: The AUC0-t of norcantharidin in tissues was in the order as follows: small intestine, stomach, uterus, kidney, testis, liver, lung, spleen, heart, brain.

Pharmacokinetic and bioequivalence studies of trospium chloride after a single-dose administration in healthy Chinese volunteers

The study aimed to compare and evaluate the bioequivalence of a new generic preparation of trospium chloride (CAS NO:10405-02-4) capsule (20 mg, test) and the available import tablet (20 mg , reference) for the requirement of state regulatory criteria in China. A randomized- sequence, 2-period crossover study was conducted in 20 healthy Chinese male volunteers in the fasted state. Blood samples were collected before and 1, 2, 3, 4, 5, 6, 7, 8, 12, 24, 36, 48, 60 h after administration of a single oral dose of 40 mg trospium chloride capsules or tablets, followed by a 7-day washout period. The concentration of trospium chloride was determined by a LC-MS/MS method. Drug And Statistical-Version 2.0 was used to calculate the pharmacokinetics parameters and assess bioequivalence of the two preparations. It was considered bioequivalent if the 90% CIs of the mean ratios (test: reference) for Cmax, AUC0-t and AUC0-∞ were within the range from 80% to 125%, respectively. The main pharmacokinetics parameters of test and reference were as follows: t1/2 was (15.11 ± 3.24) h and (16.00 ± 3.96) h; Tmax was (4.0 ± 1.2) h and (4.1 ± 0.9) h; Cmax was (3.76 ± 1.87) ng·mL - 1 and (3.70 ± 1.89) ng·mL - 1; AUC0-t was (33.51 ± 14.39) ng·mL - 1·h and (33.33 ± 14.88) ng·mL - 1·h, and the AUC0-∞ was (35.20 ± 14.88) ng·mL - 1·h and (35.16±15.17) ng·mL - 1·h. The ratios (test: reference) for Cmax, AUC0-t, and AUC0-∞ were 94.0%~111.7%, 96.4%~106.8%, and 96.1%~105.3%, respectively. No significant differences in pharmacokinetic parameters were found between preparations and periods (p>0.05). No obvious adverse events were monitored throughout the study based on clinical parameters and patient reports.

Measurement of the depth of maximum of extensive air showers above 10{18} eV

We describe the measurement of the depth of maximum, X{max}, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10;{18} eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106{-21}{+35}) g/cm{2}/decade below 10{18.24+/-0.05} eV, and (24+/-3) g/cm{2}/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm{2}. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.

Computed tomography-guided aspiration versus key-hole craniotomy for spontaneous putaminal haemorrhage: a prospective comparison of minimally invasive procedures

OBJECTIVES

To compare the effectiveness of two minimally invasive procedures, namely computed tomography-guided aspiration and the key-hole approach, in the neurosurgical management for spontaneous putaminal haemorrhage, and to explore the indications for the two approaches.

DESIGN

A multicentre, single-blinded controlled trial.

SETTING

Hospitals taking part in this trial and the sources for patients were from China. Among others, the hospitals involved in the interventions included: the Beijing Tiantan Hospital (of the Capital University of Medical Sciences), the General Hospital of People's Liberation Army, the Peking Union Hospital, and the Shanghai Huashan Hospital (of the Fudan University medical school).

PATIENTS

From September 2001 to November 2003, data were available for analysis from a total of 841 patients with spontaneous putaminal haemorrhage from 135 hospitals all over China (except Tibet, Hong Kong, Taiwan, and Macao). All follow-up data were for at least 3 months.

MAIN OUTCOME MEASURES

Mortality, Glasgow Coma Scale score, postoperative complications, Kanofsky Performance Scale score, and Barthel Index.

RESULTS

There were 563 patients who underwent computed tomography-guided aspiration, and 165 were treated by the key-hole approach. Respective mortality rates 1 month after the operation were 17.9% and 18.3%; at 3 months they were 19.4% and 19.4%. In those undergoing computed tomography-guided aspiration, mortality rates at 3 months after the operation were 28.2% in patients with Glasgow Coma Scale scores of 8 or below, as opposed to 8.2% in those with higher scores. This amounted to a 3.4-fold difference. In those treated by the key-hole approach, the corresponding rates were 30.2% and 7.6%, which amounted to a 4-fold difference. The corresponding mortality at 3 months in patients with complications was 3.9 times as great as in those without complications. In those with haematoma volumes of 70 mL or greater, it was 2.7 times as much as in those in whom the volumes below 30 mL. The postoperative complication rate of computed tomography-guided aspiration (23.7%) did not differ significantly from that in those having the key-hole approach (25.7%) [P=0.420].

CONCLUSIONS

Computed tomography-guided aspiration is not superior to the key-hole approach for treating spontaneous putaminal haemorrhage in terms of favourable outcomes, mortality, and morbidity. However, it could be the first-choice approach for those with bleeds of 50 mL or less, while the key-hole approach may be more suitable for those with larger haematomas.

Expression of cathepsin L in nasopharyngeal carcinoma and its clinical significance

AIM

To study the expression of cathepsin L in nasopharyngeal carcinoma (NPC), and analyze its relationship with clinicopathologic factors.

METHODS

The expression of cathepsin L was determined immunohistochemically in NPC, adjacent normal nasopharyngeal tissues and metastatic cervical lymph nodes. The correlation between its protein expression and clinicopathologic parameters as well as with long term follow-up data in NPC was analyzed.

RESULTS

The protein of cathepsin L was overexpressed in 47% primary tumor tissues, and in 89% metastatic cervical lymph node samples. Overexpression of cathepsin L was found to correlate with lymph node metastasis ( P = 0.04) and distant metastasis ( P = 0.01), and marginally with clinical stage and T classification, but not with patient age, gender and histological classification of tumor. Patients with overexpression of cathepsin L in tumor tissue had worse 5-year survival than those without such expression pattern ( P = 0.033). Multivariate survival analysis showed that cathepsin L protein expression level had a marginal significant correlation with prognosis of NPC.

CONCLUSION

Cathepsin L is a potential biomarker for prognosis of NPC and contributes to NPC metastasis.

Relationship between survival and estrogen receptor (ER) status in pts with metastatic breast cancer (MBC) treated with capecitabine (C) and docetaxel (D): An exploratory data analysis

1024

Background: Previous studies in pts with MBC have shown that women with ER+ tumors have a longer survival time compared to women with ER- tumors. An exploratory analysis was conducted to describe the relationship between survival and ER status among MBC pts treated with combination therapy consisting of C+D. Methods: This analysis used data from an open-label, randomized phase III trial of C+D vs D alone in pts with advanced and/or MBC. Survival analysis was used to investigate the effect of baseline ER status of the primary and metastatic tumors on overall survival (OS). ER status was defined as positive if positive for any tumor, negative if at least 1 negative test, otherwise unknown. Results: Among 506 intent-to-treat pts (randomized, received ≥1 dose), ER status was identified in 356. C+D: 90 ER+, 88 ER-; D alone: 95 ER+, 83 ER-. The unadjusted log-rank test showed a significant difference in OS between the C+D and D groups for ER+ but not ER- pts. In the ER+ group, median OS was longer in C+D vs D pts (538.5 vs 379.0 d) (hazard ratio [HR] 0.65; P=0.007). OS was significantly longer in ER+ vs ER- pts in the C+D group (538.5 vs 329.0 d) (HR 0.68; P=0.019) but not in the D group (379.0 vs 301.0 d) (HR 0.90; P=0.514). OS by time from diagnosis to recurrence and baseline tumor size showed no significant differences between ER+ and ER- pts. Conclusions: This exploratory analysis suggested a significant difference in OS between the C + D and D groups in ER+ (HR 0.65) but not ER- (HR 0.90) pts. Also, within the C+D group, the median OS was significantly longer in ER+ than ER- pts (HR 0.68).

[Table: see text]

[Table: see text]

Systemic lupus erythematosus presenting as hypoglycaemia with insulin receptor antibodies and insulin autoantibodies

A 37-year-old man presented with sweating, confusion, palpitations, hunger and tremor of 3 months duration. The symptoms disappeared after ingestion of food. After 3 months, he suffered from irregular fever, arthritis, rash, photosensitivity, and was admitted to the hospital. His antinuclear antibody, anti–double stranded DNA antibody, anti-smith antibody and lupus erythematosus cell phenomenon were all positive. Urine analysis showed albuminuria; his 24-h urine protein was 4.7 g. During hospitalisation, the patient presented with loss of consciousness three times because of hypoglycaemia. His serum insulin level during the hypoglycaemic episode was high at 490–1080 mmol/L (normal range: 6.00–27.00 mmol/L). He had never received an insulin rejection. Both insulin autoantibody and insulin receptor antibody were positive. Investigations confirmed systemic lupus erythematosus (SLE) with autoimmune hypoglycaemia. High-dose of corticosteroids, chloroquine and cyclophosphamide therapy had resulted in remission of hypoglycaemia associated with resolution of circulating antibodies to insulin and insulin receptor, and improvement in clinical and laboratory features of SLE.

Sweet's syndrome representing a flare of Behçet's disease

A case of Sweet's syndrome (SS) associated with Behçet's disease (BD) is presented. A 42-year-old Chinese woman was admitted for an eruption of tender, erythematous papules over the neck, which histological changes were typical of SS. She had a three-year history of oral and genital ulcers that was in remission for two months, but flared shortly after the eruption. SS in association with BD has been reported only in few cases. On reviewing the literature, some overlapping manifestations exist between BD and SS and it is possible that some common pathogenesis pathways may be shared by BD and SS.

Postprandial blood glucose response to a standard test meal in insulin-requiring patients with diabetes treated with insulin lispro mix 50 or human insulin mix 50

AIM

To compare the 2-h postprandial blood glucose (PPBG) excursion following a standard test meal in insulin-requiring patients with diabetes treated twice daily with human insulin mix 50 vs. insulin lispro mix 50 (LM50).

METHODS

This was a multicentre, randomised, open-label, crossover comparison of two insulin treatments for two 12-week treatment periods in 120 Chinese patients. One- and 2-h PPBG and excursion values were obtained following a standardised test meal. Fasting blood glucose (FBG), haemoglobin A1c (HbA1c), insulin dose, rate of hypoglycaemia and safety data were obtained. A crossover analysis using SAS Proc MIXED was employed.

RESULTS

Mean 2-h PPBG excursion decreased from 6.32 +/- 3.07 mmol/l at baseline to 3.47 +/- 2.97 mmol/l at end-point in the LM50 group, and from 6.31 +/- 2.88 at baseline to 5.02 +/- 3.32 mmol/l at end-point in the human insulin mix 50 group (p < 0.001). Two-hour PPBG (p = 0.004) and 1-h PPBG excursion (p < 0.001) were significantly lower with LM50 as compared with human insulin mix 50. Both treatment groups were equivalent for HbA1c control, 1-h PPBG and insulin dose requirements. Mean FBG was higher with LM50 than with human insulin mix 50 (p = 0.023). The overall incidence of treatment-emergent adverse events and hypoglycaemia rate per 30 days were similar between treatment groups.

CONCLUSIONS

Insulin lispro mix 50 provided better postprandial glycaemic control compared with human insulin mix 50 while providing the convenience of injecting immediately before meals. Both treatments were generally well tolerated by all randomly assigned patients.

Co-transplantation of bone marrow stromal cells transduced with IL-7 gene enhances immune reconstitution after allogeneic bone marrow transplantation in mice

Allogeneic bone marrow transplantation (allo-BMT) is followed by a period of profound immune deficiency, which results in significant susceptibility to infections and limits the extensive application of this approach in clinic. Here, we transduced human interleukin-7 (IL-7) gene into donor-derived bone marrow stromal cells (MSCs) using adenovirus vector, and transplanted this gene-engineered MSCs (MSC-IL-7) into lethally irradiated C57BL/6 mice to investigate their effects on immune reconstitution following allo-BMT. Recipient mice receiving MSC-IL-7 cells plus T-cell-depleted bone marrow cells of BALB/c mice showed a significant increase in thymopoiesis and homeostatic expansion of peripheral T lymphocytes. Furthermore, injection of MSC-IL-7 cells following allo-BMT protected the host from the lethality caused by acute graft-versus-host disease (GVHD) and prevented the occurrence of GVHD induced by transplanted T cells. Thus, the use of MSC-IL-7 cells may be therapeutically useful for enhancing immune reconstitution without aggravating GVHD in allo-BMT mice.

Study on relationship between anticardiolipin antibody and cerebrovascular diseases

Serum anticardiolipin antibody (ACA) was measured in 91 patients with cerebral infarction (CI), 42 patients with cerebral hemorrhage (CH) and 30 healthy controls. The results showed that the ACA in CI and CH patients was significantly higher than in controls and IgG-ACA was the most important isotype. Stroke in ACA positive group tended to be recurrent and of multi-focuses. Positive rate of IgG-ACA reached its peak within the first week after stroke onset. The results suggested that ACA was an independent risk factor in CI and CH and might be valuable in stroke prediction.

A clinical investigation on garlicin injectio for treatment of unstable angina pectoris and its actions on plasma endothelin and blood sugar levels

To investigate the therapeutic effects and mechanisms of garlicin for treatment of unstable angina pectoris (UAP), garlicin injectio was intravenously dripped 60 mg/day in 34 cases for 10 days. Nitroglycerine was used in 21 cases of the control group. The results showed that the total effective rates in improving symptoms and electrocardiogram after garlicin treatment were respectively 82% and 62%, and that the plasma endothelin and blood sugar levels were markedly lowered in cases with hyperglycemia.

A convenient method for the synthesis of DNA-recognizing polyamides in solution

A convenient method for the synthesis of polyamides containing N-methylpyrrole (Py) and N-methylimidazole (Im) in solution has been developed. Most of the building blocks have been prepared by a haloform reaction in a simple way that column chromatography can be avoided. By use of the DCC/HOBT coupling reaction, the building blocks prepared have been effectively connected to construct a variety of subchains and polyamides without employing amino protection and deprotection. By use of the present method, an eight-ring polyamide, PyPyPyPygammaPyImImPybetaDp (gamma is gamma-aminobutyric acid, beta is beta-alanine, Dp is N, N-dimethylpropyldiamine), has been synthesized by the coupling of two four-ring subchains in one step.

[Studies on chemical constituents of the fruits of Rosa bracteata var. bracteata]

The chemical constituents of Rosa bracteata Wendl. var. bracteata were studied for the first time. Six compounds were isolated from the fruits of the plant, and four of them have been identified as 5-hydroxymethyl furfural, 5-acetoxymethyl furfural, beta-sitosterol, oleanolic acid. 5-hydroxymethy furfural and 5-acetoxymethyl furfural were obtained from genus Rosa L. for the first time. Otherwise, a white wax was obtained by silica gel column chromatography, from which four main constituents were identified as nonadecene, n-docosane, hentriacontane and hexatriacontane by GC-MS.

[The treatment effect of ribavirin to hemorrhagic fever with renal syndrome on the kinetics of serum creatine phosphate kinase isoenzyme]

OBJECTIVE

To study the effect of ribavirin treatment on kinetics of serum creatine phosphate kinase isoenzyme(CK-MB) of patients with hemoarrhagic fever with renal syndrome(HFRS).

METHODS

CK-MB levels in 155 HFRS patients treated with larger dose of ribavirin and with routine therapeutic dose were observed dynamicaly, using randomly controlled double-blind method. In addition, CK-MB levels in different disease phases and different clinical types of HFRS were compared.

RESULTS

The results showed that CK-MB levels were significantly increased in febrile phase and decreased gradually to normal during convalescent phase in both groups, but in febrile phase, CK-MB levels in ribavirin-treated group and control group were 55.25 +/- 18.25 IU/L and 69.63 +/- 23.52 IU/L, respectively, the treated group had a lower level (P < 0.05). The severe and critical group treated by ribavirin showed a lower CK-MB level of 47.74 +/- 24.82 IU/L, while the control group showed a higher level of 66.08 +/- 25.01 IU/L(P < 0.05).

CONCLUSION

These results indicated that an early application of large dose of ribavirin in treatment of HFRS can reduce the serum CK-MB levels in patients with HFRS.

[Expression of interleukin-6 and its receptors in peripheral blood of patients with systemic lupus erythematosus]

OBJECTIVE

To investigate the level of interleukin-6 (IL-6) and soluble-IL-6 receptor (sIL-6R) in serum of patients with systemic lupus erythematosus (SLE) and its correlation with disease activity and to explore IL-6 signal transduction pathways in SLE patients.

METHODS

By using MTT colorimetry and ELISA, the levels of IL-6 and sIL-6R in serum from 16 patients with SLE (9 active, 7 inactive), 17 with active rheumatoid arthritis (RA) and 29 controls were measured. The expressions of acute phase reaction factor (APRF) in peripheral blood mononuclear cells (PBMCs) were also detected by using electrophoresis mobility shift assays (EMSA) after the PBMCs were isolated and then stimulated by IL-6.

RESULTS

Serum IL-6 and sIL-6R levels in active SLE patients were significantly higher than those in normal controls (P < 0.01), but were significantly lower than those in active RA patients (P < 0.01). Serum IL-6 rather than sIL-6R level in active SLE patients was significantly higher than that in inactive ones (P < 0.01). Serum IL-6 was correlated positively with the anti-dsDNA antibody (r = 0.658, P < 0.01), but not with CRP (r = 0.041, P > 0.05). There were no expression of APRF in PMNC from SLE patients and 8 normal controls, whereas PMNC from 11 RA patients expressed APRF activity (11/17).

CONCLUSION

The level of IL-6 is a useful parameter for monitoring disease activity of SLE. In active SLE, no significant elevation of serum sIL-6R and no expression of APRF in PMBCs may be responsible for mild CRP elevation.

Epidermal growth factor receptor participates in growth hormone signaling pathway in cardiac myocytes of neonatal rat

OBJECTIVE

To examine whether growth hormone (GH) promotes the phosphorylation of epidermal growth factor (EGF) receptor and to elucidate the mechanisms by which EGF receptors were transactivated by GH stimulation.

METHODS

Cultured cardiac myocytes were stimulated by GH directly or pretreated with inhibitors before GH stimulation. The phosphorylations of EGF receptor and JAK2 were examined with immunoprecipitation followed by Western blotting using anti-phosphotyrosine antibody (4G10). The activities of extracellular signal-regulated kinases (ERKs) were assayed with the method of MBP-containing gel.

RESULTS

GH stimulated phosphorylation of EGF receptor in a time-dependent manner. Tyrphostin AG1478, a selective inhibitor of EGF receptor, strongly suppressed GH-induced ERK activation, while tyrphostin AG1295, a selective inhibitor of PDGF receptor, had no effects on the activation of ERKs stimulated by GH in cardiac myocytes. In addition, GH induced tyrosine phosphorylation of JAK2, a cytoplasmic protein tyrosine kinase, in cardiac myocytes. Moreover, tyrphostin B42, an inhibitor of JAK2 suppressed GH-induced phosphorylation of EGF receptor as well as GH-induced activation of ERKs in cardiac myocytes.

CONCLUSIONS

GH evokes the phosphorylation of EGF receptor in cardiac myocytes through activating JAK2. Phosphorylated EGF receptor plays a critical role in GH signaling pathway leading to ERK activation in cardiac myocytes.

[Kinetics of the Ca(2+)-activated K+ channel in Ca2+ induced cortex neurons damage]

Ca(2+)-activated K+ channels were studied by using the patch clamp technique of single channel recordings from the primary culture fetal SD rat cortex neurons. Besides their physiologic characters, the effects of increasing cytosolic and cytoplasmic Ca2+ triggered neuronal damage were also studied. The results showed that Kca with conductance around 170PS was predominant in the rat cortex neurons. These channels almost did not open at physiologic intracellular free Ca2+ concentration (10(-8) mol/L), but was extremely activated at intracellular free Ca2+ concentration (10(-6) mol/L). So the open probabilities of the KCa in the cortex neurons obviously depended on the concentration of cytoplasmic Ca2+ and membrane potential. The KCa activated by increasing of intracellular Ca2+ during the early stage of anoxia may be a protective reaction of ischemic neurons.

Cloning and characterization of human guanine deaminase. Purification and partial amino acid sequence of the mouse protein

Mouse erythrocyte guanine deaminase has been purified to homogeneity. The native enzyme was dimeric, being comprised of two identical subunits of approximately 50,000 Da. The protein sequence was obtained from five cyanogen bromide cleavage products giving sequences ranging from 12 to 25 amino acids in length and corresponding to 99 residues. Basic Local Alignment Search Tool (BLAST) analysis of expressed sequence databases enabled the retrieval of a human expressed sequence tag cDNA clone highly homologous to one of the mouse peptide sequences. The presumed coding region of this clone was used to screen a human kidney cDNA library and secondarily to polymerase chain reaction-amplify the full-length coding sequence of the human brain cDNA corresponding to an open reading frame of 1365 nucleotides and encoding a protein of 51,040 Da. Comparison of the mouse peptide sequences with the inferred human protein sequence revealed 88 of 99 residues to be identical. The human coding sequence of the putative enzyme was subcloned into the bacterial expression vector pMAL-c2, expressed, purified, and characterized as having guanine deaminase activity with a Km for guanine of 9.5 +/- 1.7 microM. The protein shares a 9-residue motif with other aminohydrolases and amidohydrolases (PGX[VI]DXH[TVI]H) that has been shown to be ligated with heavy metal ions, commonly zinc. The purified recombinant guanine deaminase was found to contain approximately 1 atom of zinc per 51-kDa monomer.

Electron impact mass spectral characteristics and fragmentation pathways of isomeric tetradecadien-1-ols

Characteristics of mass spectra of isomeric tetradecadien-1-ols were investigated by electron impact mass spectrometry, and mass spectral fragmentation pathways were proposed based on collision-induced dissociation experiments and mass-analyzed ion kinetic energy spectrometry. Copyright 1999 John Wiley & Sons, Ltd.

YAG Laser End and Side Pumped by a Laser Diode

A combined end and side pump approach for a YAG laser pumped by a laser diode is proposed. The theoretical analysis of the total pump efficiency of the end and side pump module is presented. A laser-diode-pumped YAG laser is successfully demonstrated by use of this pump configuration. The experimental pump threshold is 81.2 mJ, the maximum output is 4.4 mJ, and the optical efficiency is approximately 3.1% for Q-switched operation of the YAG laser.

[Molecular analysis of HLA-DR beta polymorphism in Han nationality patients with rheumatoid arthritis]

OBJECTIVE

To analyze the molecular basis for HLA-DR associations with rheumatoid arthritis(RA) in the han nationality of Chinese population.

METHODS

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques were used to dertermine DRB1 alleles in 35 unrelated patients with RA and 100 healthy controls from the Han nationality.

RESULTS

The frequency of DR4(DRB1 * 04) was 51.4% in RA patients and 24.0% in the healthy controls(P < 0.01, RR = 3.3). There was a significant increase in the presence of the amino acid sequences QKRAA or QRRAA both in the RA patients overall compared with the healthy group(65.7% vs 30.0%, P < 0.001) and in DR4+ RA patients compared with DR4+ healthy individuals(100% vs 75.0%, P < 0.05). Substitution of residues in QKRAA, V85 and G86 appeared to correlate with relative risk for RA, among the subjects having 0-1 amino acid substitution, RA occurred in 48.8%, whereas in subjects with 2-3 amino acid changes, RA was present in only 16.7%.

CONCLUSION

These results suggest that DR4 is strongly associated with RA in the Han nationality, and the dominant effect that determines susceptibility to RA is associated with QKRAA or QRRAA as well as V85 and G86.

[Adhesion of erythrocytes of patients with transient ischemic attack to injured endothelial cells]

Adherence of erythrocytes of patients with transient ischemic attack(TIA) to human umbilical vein endothelial cells(HUVEC) treated with H2O2 were quantitatively studied in the flow chamber system. The results showed that injured HUVECs enhanced the adherence of erythrocytes to endothelial cells in patients with TIA. The increased adhesion of erythrocytes to endothelial cells might promote the vascular damage. Consequently endothelium might play an important role in the increased adhesiveness of TIA RBC to endothelial cells.

The embryonic development of the human lamina cribrosa

OBJECTIVE

To investigate the embryonic development of lamina cribrosa of human eyes.

METHODS

The lamina cribrosa of 291 eyes were studied including 260 eyes taken from embryos and fetus of 7 weeks to full term and 31 eyes from infants under 1 year of age by using light microscopy (LMS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM).

RESULTS

From observations, it was found that the development of the lamina cribrosa was lagged behind the development of the optic nerve.

CONCLUSIONS

In eyes taken from embryos or fetus less than 4 months of pregnancy, only ectodermal primordium of the lamina cribrosa could be seen. The initial scleral part of the lamina cribrosa began its formation in the 5th month of fetus. The fibrous tissue originating from the choroid and optic nerve sheath contributed to the formation of the lamina cribrosa in the 8th month fetus. At this time, the morphology of the lamina cribrosa is similar to that of an adult, however the thickness of the structure is still getting increased up to one year after birth.

[Investigation of potency to produce interleukin-2 of the peripheral blood T lymphocytes in patients with hemorrhagic stroke]

For further understanding the changes in immune function of the patients with hemorrhagic stroke, we investigated the activity of interleukin-2 (IL-2) in the peripheral blood T lymphocytes from 32 patients. The results showed that the levels of IL-2 in the patients were lower than those of the healthy controls, but no significant difference was observed between the cerebral hemorrhage group and subarachnoid hemorrhage group. It suggests the cellular immune function of patients at the acute period is low. We consider that IL-2 might be of use as a kind of therapeutic measure to modulate patients' immune function and treat the diseases.

[Properties of adherence of erythrocytes to endothelial cells in patients with ischemic stroke]

Adherence of erythrocytes to human umbilical vein endothelial cells (HUVEC) in patients with cerebral thrombosis and transient ischemic attack (TIA) were quantitatively studied in the flow chamber system, compared with that in healthy subjects. We found: (a) The adherence of erythrocytes to HUVEC in patients with cerebral thrombosis and TIA increased, compared with that in healthy subjects; (b) The adhesion of erythrocytes to HUVEC in patients with TIA was not significantly different from that of patients with cerebral thrombosis. These suggested that the increased adhesion of erythrocytes to endothelial cells might play an important role in the pathologic process of ischemic stroke.

[Study on enterovirus aetiology of CNS infection in Shantou]

Enterovirus isolation and serological assay were done in 236 cases of CNS infection in Shantou. 62 strains of virus (from 55 cases) were isolated from 257 samples of 236 cases (24.1%). 48 cases were positive among 57 cases (84.2%) by serological assay. 78 cases were positive for virus isolation and/or serological assay (33.1%). Virus infection included 33 cases of poliovirus (including 6 polio-I, 18 polio-II, 4 polio-III, 5 mixed infections), 21 cases of Coxsackie virus (including 6 CoxA24,7 CoxB1,2 CoxB4 and 6 CoxB5), 11 cases of ECHO virus (including 5 ECHO-7,2 ECHO-24 and each one of ECHO-11, 12, 15, 27), 10 cases of Enterovirus (including 3 EV-70, 7 EV-71), and 3 cases of mixed viral infection.