[Clinical observation on small doses Tripterygium wilfordii polyglycoside combined with methotrexate in treating rheumatoid arthritis]

OBJECTIVE

To observe the effect and adverse reaction of small doses Tripterygium wilfordii polyglycoside (TWP) combined with methotrexate (MT) in treating rheumatoid arthritis (RA).

METHODS

Seventy RA patients were randomly divided into two groups, the control group (35 patients) and the TWP combined MT Group (TWPM group). Both of them were continued to use the non-steroidal anti-inflammatory drugs. The control group took MT 15 mg orally, once every week; the TWPM group took TWP 10 mg orally, 3 times a day, and MT 7.5 mg orally once every week. The clinical effect and adverse reaction after treatment were evaluated.

RESULTS

The markedly effective rate in the control group and the TWPM group was 28.6% and 34.3% respectively, with no significant difference (P > 0.05). Data of symptoms and signs, erythrocyte sedimentation rate (ESR), rheumatoid factor (RF) were determined respectively with significant difference (P < 0.01). The rate of adverse reaction was 20 cases-times in the control group and 8 cases-times in the TWPM group.

CONCLUSION

MT combined small doses of TWP in treating RA has better effect and less adverse reactions than un-combined MT.

Recent developments on ketolides and macrolides

Recent semi-synthetic studies of erythromycin A culminated in the discovery of two ketolide drug candidates, HMR-3647 and ABT-773, for the treatment of community-acquired bacterial infections caused by both macrolide- and beta-lactam-susceptible and -resistant S. pneumoniae, gram negative bacteria, and intracellular atypical pathogens. The discovery of ketolides has rekindled interest in macrolides, and recent efforts have also led to a novel class of 4''-carbamates with activity against macrolide-resistant organisms. This review is an account of recent developments on ketolides and macrolides in terms of both chemistry and antibacterial activity.

Effects of recombinant human basic fibroblast growth factor on restenosis after arterial endothelial injury in rats

AIM

To study the preventive effect of recombinant human basic fibroblast growth factor (rh-bFGF) on restenosis after percutaneous transluminal coronary angioplasty (PTCA).

METHODS

Sixty male Wistar rats were randomly divided into sham operation group, intima injured group, and intima injured plus rh-bFGF treated group. Rat carotid arteries were injured using a balloon catheter except sham operation group. The rats of rh-bFGF treated group were injected im rh-bFGF 10 kU . kg-1 . d-1 after intima was injured. Ten rats in each group were killed on d 7 and d 14 after injury, respectively. [3H]Thymidine incorporation assay and pathological examination were carried out to each vessel.

RESULTS

(1) Seven days after injury, the average intimal thickness in sham operation group, intima injured group, and rh-bFGF treated group was (7 +/- 1), (32 +/- 11), and (17 +/- 3) micron; average intimal area was (384 +/- 145), (1530 +/- 817), and (586 +/- 185) micron2; the numbers of smooth muscle cells in neointima per transect were 0 +/- 0, 146 +/- 18, and 105 +/- 26; the ratio of the collagen area to intimal area plus medial area were 0.29 +/- 0.09, 0.7 +/- 0.3, and 0.30 +/- 0.14; [3H]thymidine incorporation were (17 +/- 6), (62 +/- 23), (20 +/- 8) kBq/g tissue, respectively. (2) Fourteen days after injury, the average intimal thickness of sham operation group, intima injured group, and rh-bFGF treated group was (8 +/- 1), (41 +/- 9), and (20 +/- 3) micron; average intimal area was (391 +/- 134), (1761 +/- 337), and (731 +/- 124) micron2; the numbers of smooth muscle cells in neointima per transect were 0 +/- 0, 145 +/- 9, and 102 +/- 6; the ratio of collagen area to intimal area plus medial area were 0.28 +/- 0.14, 0.59 +/- 0.21, and 0.38 +/- 0.03; [3H]thymidine incorporation was (15 +/- 4), (57 +/- 11), and (22 +/- 6) kBq/g tissue, respectively.

CONCLUSION

Large dosage of rh-bFGF inhibits neointimal hyperplasia and reduces restenosis after balloon injury.

Correlation of acoustic velocity of synovial fluid with markers of inflammation in arthritic patients

Analysis of synovial fluid is important in the evaluation and treatment of arthritic conditions. This study measured the acoustic velocity of synovial fluids in patients with degenerative joint diseases, crystal arthropathy, and other inflammatory arthropathies using the ultrasonic pulse-echo method. The measured acoustic velocities of these bio-fluids were then correlated with clinical parameters including the synovial white blood cell count (WBC), clarity, viscosity, string test, erythrocyte sedimentation rate (ESR), and serum C-reactive protein (CRP). Results showed that the acoustic velocities were correlated with ESR (p = 0.0016) and CRP (p = 0.0001). The mean acoustic velocity of inflammatory synovial fluids, defined as synovial fluids with WBCs of more than 2000/mm3, was greater than that of synovial fluids with WBCs of less than 2000/mm3 (1550 +/- 4.5 m/s vs 1544 +/- 1.5 m/s, p = 0.007). This study demonstrated that the acoustic velocity of synovial fluid correlates well with severity of inflammation. These findings suggest that measurement of acoustic velocity may be useful in the clinical evaluation and management of arthritic conditions.

Macrophage accumulation associated with rat cardiac allograft rejection detected by magnetic resonance imaging with ultrasmall superparamagnetic iron oxide particles

BACKGROUND

Acute cardiac allograft rejection continues to be the cause of graft loss and contributes to the morbidity and mortality after cardiac transplantation. In this study, we report a new method for detecting organ rejection in transplantation with an MR-based technique using dextran-coated ultrasmall superparamagnetic iron oxide (USPIO) particles. These particles ( approximately 27 nm in diameter) are known to shorten relaxation times in MRI experiments.

METHODS AND RESULTS

A new rat model of heterotopic heart and lung transplantation has been developed for MRI experiments. Allotransplantations (DA-->BN) were performed (n=8), with syngeneic transplantations (BN-->BN) serving as controls (n=8). MR images were obtained with a gradient echo method. At postoperative day 7, allotransplants developed moderate rejection as determined histopathologically. A significant reduction in MR signal intensity was observed after USPIO injection into rats with allotransplanted hearts. Syngeneic transplants showed no differences in MR signal intensity before and after USPIO injections. After injection of USPIO particles at postoperative day 6, a group of allotransplanted rats was treated with cyclosporin A (3 mg/kg). Animals treated with cyclosporin A for 7 days showed no reduction in MR signal intensity after USPIO reinjection at day 14, whereas animals treated for 4 days showed a significant decrease in MR signal intensity in the transplanted hearts indicative of acute graft rejection. Pathological analysis of these animals revealed that dextran-coated USPIO particles were taken up by the infiltrating macrophages that accumulated within the rejecting cardiac graft.

CONCLUSIONS

This MRI method offers promise as a noninvasive method for detecting transplant allograft rejection.

Angiotensin-converting enzyme inhibitor preserves p21 and endothelial nitric oxide synthase expression in monocrotaline-induced pulmonary arterial hypertension in rats

BACKGROUND

Pulmonary arterial hypertension (PAH) is associated with structural changes in the pulmonary vasculature characterized by the proliferation of cellular components of the vessels. ACE inhibitor (ACEI) may have beneficial effects in treating PAH, but its precise mechanism of action in the remodeling process is unclear. p21 is a cyclin-dependent kinase inhibitor that may have a protective role in this process by inhibiting cellular proliferation. Endothelial nitric oxide synthase (eNOS) has also been shown to be protective by its vasodilatory effect. Therefore, we investigated whether expression of p21 and eNOS was modulated by ACEI treatment in a rat model.

METHODS AND RESULTS

Monocrotaline (MCT) was administered to 2 groups of Sprague-Dawley rats fed a high-cholesterol diet, ie, one group received MCT concomitantly with enalapril treatment (MCT(+)/ACEI(+) rats), and the other group did not receive enalapril (MCT(+)/ACEI(-) rats). After 5 weeks, MRI showed right ventricular hypertrophy in MCT(+)/ACEI(-) rats. MCT(+)/ACEI(+) rats showed a preserved right ventricular morphology. Isolated pulmonary perfusion studies showed that ACEI significantly upregulated NO production, as measured by nitrite levels. Addition of N-methyl-D-glucamine dithiocarbamate-Fe solution, an NO-trapping agent, reversed the basal vasodilatory effect of ACEI in the pulmonary vasculature. Immunoblot analysis showed decreased p21 and eNOS expression in the lung in MCT(+)/ACEI(-) rats, whereas their expression was preserved with enalapril treatment.

CONCLUSIONS

ACEI suppresses the development of MCT-induced PAH in rats. The mechanism of action might involve the preservation of p21 and eNOS expression. Both p21 and endothelium-derived NO appear to have protective roles in the development of PAH.

Enhanced susceptibility to pulmonary infection with Burkholderia cepacia in Cftr(-/-) mice

Progressive pulmonary infection is the dominant clinical feature of cystic fibrosis (CF), but the molecular basis for this susceptibility remains incompletely understood. To study this problem, we developed a model of chronic pneumonia by repeated instillation of a clinical isolate of Burkholderia cepacia (genomovar III, ET12 strain), an opportunistic gram-negative bacterium, from a case of CF into the lungs of Cftr (m1unc-/-) (Cftr(-/-)) and congenic Cftr(+/+) controls. Nine days after the last instillation, the CF transmembrane regulator knockout mice showed persistence of viable bacteria with chronic severe bronchopneumonia while wild-type mice remained healthy. The histopathological changes in the lungs of the susceptible Cftr(-/-) mice were characterized by infiltration of a mixed inflammatory-cell population into the peribronchiolar and perivascular spaces, Clara cell hyperplasia, mucus hypersecretion in airways, and exudation into alveolar airspaces by a mixed population of macrophages and neutrophils. An increased proportion of neutrophils was observed in bronchoalveolar lavage fluid from the Cftr(-/-) mice, which, despite an increased bacterial load, demonstrated minimal evidence of activation. Alveolar macrophages from Cftr(-/-) mice also demonstrated suboptimal activation. These observations suggest that the pulmonary host defenses are compromised in lungs from animals with CF, as manifested by increased susceptibility to bacterial infection and lung injury. This murine model of chronic pneumonia thus reflects, in part, the situation in human patients and may help elucidate the mechanisms leading to defective host defense in CF.

Adult isolated hypoplasia of left pulmonary artery with exertional angina and abnormal exercise stress test: a case report and treatment implication

Pulmonary artery hypoplasia, either congenital or acquired, is a rare abnormality seen in adults. We reported the first case of adult, isolated, left pulmonary artery hypoplasia, with exertional angina and prominent ST depression in exercise stress test, that seemed to be caused by exertional hypoxemia. Several vasodilators, including nitroglycerin, prostaglandin E1, and nifedipine, were administered individually, each with subsequent hemodynamic monitoring, pulse oximetric monitoring, and exercise test. Vasodilator administrations reduced pulmonary vascular resistance (baseline, 599; vasodilators, 306, 211, and 284 dyne x sec x m2/cm5, respectively) and attenuated ST depression (by 52, 72, and 27%, respectively) but without an immediate benefit on exercise tolerance. All vasodilators except nifedipine ameliorated exertional hypoxemia (expressed by arterial oxygen saturation during peak exercise, baseline, 69%; vasodilators, 85, 78, and 65%, respectively). Additional oxygen supply after nitroglycerin administration further benefited exertional hypoxemia (arterial oxygen saturation, 96%) and exercise ST depression (attenuated by 82%).

Effect of recombinant human basic fibroblast growth factor on acute inflammation in mice and rats

AIM

To investigate the anti-inflammatory effects of recombinant human basic fibroblast growth factor (rh-bFGF).

METHODS

Several inflammation models such as croton oil-induced ear swelling, carrageenan-induced hind paw edema, and acute peritonitis in rats or mice were prepared. Superoxide dismutase (SOD) activity was measured by hydroxyamine method, nitric oxide (NO) concentration by Griess reaction assay, nitric oxide synthase (NOS) activity by NADPH-diaphoras stain assay, N-acetyl-beta- D-glucosaminidase (NAG) activity by colorimetry, prostaglandin E2 (PGE2) production by radioimmunoassay (RIA), malondialdehyde (MDA) content by thiobarbituric acid (TBA) fluorescence technique, and protein content by Coomassie brilliant blue method in peritoneal exudate in rats.

RESULTS

Recombinant human bFGF 2, 4 kU/kg im inhibited croton oil-induced ear swelling and carrageenan-induced paw edema in mice. In addition, rh-bFGF 2, 4 kU/kg im reduced neutrophil counts in the rat peritoneal exudate, and lessened protein content in peritoneal exudate in rats and mice. In the rat peritonitis induced by carrageenan, rh-bFGF 4 kU/kg decreased the MDA and NO levels, inhibited the NOS activity, augmented the SOD activity, and lowered the production of PGE(2) in exudate. However, rh-bFGF had no effect on NAG content.

CONCLUSION

Recombinant human bFGF has an anti-inflammatory effect and its mechanisms are related to the inhibition of NOS activity, reduction of NO, MDA, and PGE(2) content, and increase of SOD activity.

On-column amperometric detection of ofloxacin and pasiniazid in urine by capillary electrophoresis with an improved fractured joint and small detection cell

An improved high-voltage electric field isolating joint and small detection cell have been carefully designed and fabricated. The joint possesses short steady time, high electric conductance efficiency and high performance. The cell is convenient to install and remove the capillaries with and without the joint, as well as to fix, adjust and insert the microelectrode into the detection capillary. Using the joint and the cell, an analytical method for determination of ofloxacin (Oflx) and pasiniazid (Ipa) in urine by capillary electrophoresis with on-column amperometric detection was developed. The calibration lines were linear in the range of 10-100 mg l-1 of Oflx and 1.0-50 mg l-1 of Ipa, respectively. The detection limits were 8.5 mg l-1 of Oflx and 0.80 mg l-1 of Ipa. Their recovery ranged from 101 to 104%. The accuracy and intra-day and inter-day reproducibility of Oflx and Ipa were determined with satisfactory results. This method was successfully used for determining Oflx and Ipa in human urine.

[Expression of heme oxygenase-1 in neonatal rat cardiocytes induced by lipopolysaccharide]

To study the alterations of heme oxygenase-1 mRNA in neonatal rat cardiomyocytes (NRCMs) induced by lipopolysaccharide (LPS) and the role of heme oxygenase-1 (HO-1) in the LPS induced disorders of myocardium function, 10 (L, 6 h), 30 (M, 6 h), 50 micrograms/ml (H, 6 h) LPS and 10 micrograms/ml LPS + 10 mumol/ml Zn-protoporphyrin-IX (ZnPPIX; L + I, 6 h) and 10 mumol/ml ZnPPIX alone (I, 6 h) were added to the medium for a 6-hour culture of NRCMs, and 10 micrograms/ml LPS for 9 h (L, 9 h) and 18 h (L, 18 h) cultures. LDH release and MDA contents of the cells were measured. When NRCMs were collected, Trypan blue stain method was used to examine the mortality (the rate of Trypan blue uptake) of NRCMs. HO-1 mRNA expression was examined by Northern blot. The results showed that HO-1 mRNA expression of NRCMs increased gradually along with the increase of LPS concentration below the level of 30 micrograms/ml. When the final concentrations of LPS were 10 and 30 micrograms/ml, the HO-1 mRNA expression of NRCMs increased by 81.2% and 126.3% respectively compared with control. When the final concentration of LPS was 50 micrograms/ml, the HO-1 mRNA expression decreased to the level of 10 micrograms/ml group. When the final concentration was 10 micrograms/ml, the HO-1 mRNA expression increased gradually along with the culture time. After a 9- or 18-hour culture, the HO-1 mRNA expression of NRCMs increased by 93.6% and 105.8% respectively compared with control. Only when NRCMs had been cultured with 30, 50 micrograms/ml LPS and 10 micrograms/ml LPS + 10 mumol/ml ZnPPIX for 6 h and 10 micrograms/ml LPS for 18 h, the rate of Trypan blue stain uptake, MDA contents and LDH release significantly increased. With 10 micrograms/ml LPS alone and 10 mumol/ml ZnPPIX alone for 6 h, the above parameters were not significantly increased (P > 0.05). The results demonstrate that LPS induces HO-1 mRNA expression of NRCMs dose- and time-dependently to some extent. The inducible HO can protect NRCMs from injury and thus play an important role in pathogenesis of myocardium under LPS.

Energy expenditure of wheeling and walking during prosthetic rehabilitation in a woman with bilateral transfemoral amputations

OBJECTIVE

To compare the energy expenditure of locomotion by wheelchair with that required for prosthetic ambulation in a person with bilateral transfemoral (TF) amputations.

DESIGN

Observational, single patient, descriptive.

SETTING

An 80-meter long rectangular hallway in a rehabilitation unit.

PATIENT

A 41-year-old woman with bilateral TF amputations that were performed 79 days before her admission to the rehabilitation unit.

MAIN OUTCOME MEASURES

The oxygen uptake, oxygen cost, heart rate, speed, cadence, and stride length of walking measured during a 4-month course of prosthetic rehabilitation. Five locomotion conditions were evaluated: (1) wheelchair propulsion, (2) walking with short-leg prostheses (stubbies) and a walker, (3) long-leg prostheses and a walker, (4) long-leg prostheses without knee mechanism and axillary crutches, and (5) long-leg prostheses with right polycentric knee and left locked knee and axillary crutches. A portable and telemetric system was used to measure the metabolic parameters. An arm ergometry graded exercise test was performed at the end of rehabilitation.

RESULTS

Oxygen cost (range, 466%--707% of that of wheeling) and heart rate (range, 106%--116% of that of wheeling) were higher during walking with various combinations of prostheses and walking aids. The speed of prosthetic walking was only 24% to 33% of that of wheeling. Our patient preferred using a wheelchair to prosthetic walking after discharge.

CONCLUSIONS

People with bilateral TF amputations require very high cardiorespiratory endurance to fulfill the energy demand during prosthetic rehabilitation. The high energy cost of prosthetic walking will limit its application in daily activities.

The C termini of Arabidopsis cryptochromes mediate a constitutive light response

Cryptochrome blue light photoreceptors share sequence similarity to photolyases, flavoproteins that mediate light-dependent DNA repair. However, cryptochromes lack photolyase activity and are characterized by distinguishing C-terminal domains. Here we show that the signaling mechanism of Arabidopsis cryptochrome is mediated through the C terminus. On fusion with beta-glucuronidase (GUS), both the Arabidopsis CRY1 C-terminal domain (CCT1) and the CRY2 C-terminal domain (CCT2) mediate a constitutive light response. This constitutive photomorphogenic (COP) phenotype was not observed for mutants of cct1 corresponding to previously described cry1 alleles. We propose that the C-terminal domain of Arabidopsis cryptochrome is maintained in an inactive state in the dark. Irradiation with blue light relieves this repression, presumably through an intra- or intermolecular redox reaction mediated through the flavin bound to the N-terminal photolyase-like domain.

Abdominal fat pad mass reduction by in ovo administration of anti-adipocyte monoclonal antibodies in chickens

The effect of in ovo administration of antiadipocyte monoclonal antibodies (MAb) on growth and adipose tissue development in chickens was investigated. In Trial 1, 60 fertilized eggs from layer-type chickens were injected into allantoic circulation with different amounts of MAb against chicken adipocyte plasma membranes (0, 0.05, 0.1, 0.2, and 0.4 mg) on Day 15 of embryogenesis. In Trial 2, 180 fertilized broiler eggs were injected into allantoic circulation with 0.2 mg MAb on Day 15 of embryogenesis. In Trial 1, high doses (0.2 and 0.4 mg) of MAb in in ovo injection reduced (P < or = 0.05) abdominal fat pad weight without affecting total body weight at 42 d of age. Only the highest dose (0.4 mg) significantly reduced hatch rate. In Trial 2, adipose tissue (pectoral, femoral, and abdominal), major organ (heart, liver, and spleen), and total body weights at 14 d of age were not affected by in ovo injection. Hatch success rate of eggs was not significantly different among treatments. However, by 6 wk of age, in ovo injection of MAb significantly reduced (P < or = 0.05) abdominal fat pad weight by more than 28%. This relative fat pad mass reduction occurred without affecting femoral or pectoral fat tissues. Total body weight and feed intake were not affected among treatments. Our experiments demonstrated for the first time that in ovo administration of anti-adipocyte MAb on Day 15 of embryogenesis reduced the chicken abdominal fat pad mass by 42 d of age without affecting growth or body weight.

[Gene cloning, expression and purification of its production of recombinant human superoxide dismutase]

Human SOD cDNA was cloned and constructed an expression plasmid with high sufficient and stabilility expression in E. coli. The rhSOD cDNA was amplified by RT-PCR with the template of the total RNA extracted from human liver tissue. The expression plasmid, pLY-4/rhSOD, containing rhSOD cDNA, was transformed into the E. coli JF1125. The sequence of the cloned rhSOD cDNA was identified with the reported data. The expression level reached to more than 68% of total bacteria proteins; The technology for protein renature and purification was efficiency and fast. The purity of the final products reached more than 98%. The value of bioactivity was determined as 2529 u/mg. This study gave enough support for production of rhSOD by biotechnology.

Effects of tri-o-cresyl phosphate on serum estrogen and progesterone concentration and ATPase activity in the shell gland of adult hens

The activities of calcium-activated ATPase (Ca2+-ATPase) and calcium magnesium-activated ATPase (Ca2+-Mg2+-ATPase) in the shell gland, and concentrations of 17beta-estradiol (E2) and progesterone in serum were monitored, respectively, from hens orally dosed with tri-o-cresyl phosphate (TOCP) (750 mg/kg). Treated birds were monitored daily for laying and development of delayed neurotoxicity, and activities of Ca2+-ATPase and Ca2+-Mg2+-ATPase were measured at 7 and 10 days after dosing. TOCP-treated birds manifested motor deficit by 7-9 days postdosing, while hens administered vehicle exhibited no signs of delayed neurotoxicity. Ca2+-ATPase and Ca2+-Mg2+-ATPase activities of shell glands from TOCP-dosed hens were not significantly affected (P > 0.05). The serum E2 concentration was significantly reduced in TOCP-treated hens (P < 0.01); however, progesterone levels were unaffected.

The clinical features and prognosis of lupus with disease onset at age 65 and older

Systemic lupus erythematosus (SLE) in the elderly is uncommon and rarely reported with disease onset at age 65 and older. The aim of this study is to retrospectively analyze the influence of age at disease onset on the clinical features and prognosis of SLE. From 1988 to 1998, we encountered 21 lupus patients with disease onset at age 65 and older (all are included in group A). For comparison, 21 lupus patients with disease onset between 50-64 years of age (group B) and 152 lupus patients with disease onset before 50 years of age (group C) were obtained by a simple random sampling method from the hospital registry. Clinical features as included in the 1982 ARA revised criteria for classification of SLE and survival rate were analyzed and compared among these three groups. Group A had a smaller female to male ratio, longer duration from disease onset to diagnosis, less malar rash, more discoid lupus, and shorter survival rate that group C. There was no statistically significant difference in clinical features and survival between groups A and B, as well as between female and male patients of these two groups. The main cause of death in group A was septic shock. In conclusion, the clinical features and prognosis of SLE were influenced by the age at disease onset. However, clinical features and prognosis of SLE were similar in both late-onset lupus groups.

Beta-cell dysfunction in 48-hour glucose-infused rats is not a consequence of elevated plasma lipid or islet triglyceride levels

The abnormal insulin secretion found in human diabetics and animal models of diabetes has been attributed to the deleterious effects of chronic hyperglycemia and/or elevated circulating levels of nonesterified fatty acids (NEFAs). In this study, abnormal glucose-induced insulin secretion (GIIS) was generated by a 48-hour infusion of glucose and assessed by the isolated perfused pancreas technique. In these hyperglycemic animals, abnormal GIIS is accompanied by a decrease in plasma NEFAs, while plasma and, more importantly, islet triglycerides remain at levels comparable to those in the controls. It is concluded that the abnormal insulin secretion in this glucose infusion model was likely caused by 48 hours of hyperglycemia and not by changes in circulating or islet lipids.

Inhibition of chicken adipocyte differentiation by in vitro exposure to monoclonal antibodies against embryonic chicken adipocyte plasma membranes

Specific monoclonal antibodies (MAb) against adipocyte precursor antigens were developed. These MAb identified adipocyte precursors and reduced their prominence in primary stromal-vascular (SV) cultures by complement-mediated cytotoxicity or by inhibition of differentiation. Binding of antibodies to chicken adipocyte precursors was confirmed by immunofluorescence visual examination following secondary exposure to fluorescein isothiocyanate-conjugated goat antimouse IgG. Cross-reaction of MAb with muscle, kidney, liver, fibroblasts, and other cell types not containing lipid droplets was not observed in primary cultures. Adipocyte precursors were obtained from 18-d chick embryo adipose tissue by collagenase digestion to investigate complement-mediated cytotoxicity of preadipocytes. Cultures were maintained in Medium 199 with 5% fetal bovine serum (FBS) for 4 d. Subsequently, Medium 199 supplemented with 10% chicken serum initiated adipocyte differentiation. At Day 5 postinoculation, individual or combinations of MAb were administered to preadipocyte cultures; rabbit complement was added 30 min later. After 1 d of incubation, four of the six individual MAb with complement significantly (P < 0.05) reduced the number of fat cell clusters that developed by 40 to 60%. These MAb in the presence of complement also significantly (P < 0.05) reduced mean cell width and apparent cell area or cell cluster area of lipid-containing cells. Neither MAb nor complement alone reduced fat cell cluster number, cell size, or cluster size. Treatment with pools of two and four MAb decreased the total amount of MAb protein required to reduce fat cell cluster number. Four antibodies, alone or in combination, reduced fat cell cluster development in a complement-dependent manner.

[Site-directed mutagenesis and effects on the enzymatic properties of subtilisin E]

Site-directed mutagenesis was used to investigate the effects of S221C/P225A, N118S/S221C/P225A, D60N/N118S/S221C/P225A and Q103R/N118S/S221C/P225A mutations on the properties of Subtilisin E. It was found that S221C/P225A mutant is 73,000-fold decreased in amidase activity than subtilisin E and 3-fold increased than subtiligase in the ratio of esterase/amidase; N118S/S221C/P225A mutant has 3.6-fold and 15-fold decreased in amidase and esterase activity respectively and as a result, it has a 4-fold lower in the ratio of amidase/esterase than S221C/P225A mutant; Although it has no effect on the esterase activity, D60N/N118S/S221C/P225A mutant enhanced its ratio of amidase/esterase by 15 fold, 3.3-fold and 10.3 fold compared to N118S/S221C/P225A mutant, S221C/P225A mutant and subtiligase respectively; Q103R/N118S/S221C/P225A mutant, however, has a 5-fold enhanced in the amidase activity and 55-fold and 1000-fold decrease in the esterase activity and the ratio of esterase/amidase compared to N118S/S221C/P225A.

[Effect of extract from overground part of Tripterygium wilfordii Hook. f. on Masugi nephritis in rabbits]

OBJECTIVE

To observe the effect of extract from overground part of Trpterygium wilfordii on Masugi nephritis in rabbits.

METHOD

Masugi nephritis was made by giving i.v. the rabbit an injection of sheep antirabbit serum.

RESULT

The extract could effectively inhibit the increase of uric protein, serum BUN, creatinine and glomerulus cells in rabbits.

CONCLUSION

The extract from overground part of Tripterygium wilfordii has better curative effect on Masugi nephritis in rabbits.

On-column amperometric detection in capillary electrophoresis with an improved high-voltage electric field decoupler

An improved fabrication method for a decoupler for on-column amperometric detection in capillary electrophoresis (CE) is described. The decoupler is fabricated by etching one side-wall of the capillary with hydrofluoric acid after the polymer coating had been etched by laser, then the etched hole is sealed with adhesive. The steady time, electric conductivity efficiency and performance are investigated. On-column amperometric detection by CE of para-substituted phenols was carried out by coupling with a carbon-fiber microelectrode (10-microm diameter) and a practical small electrochemical detection cell.

[Mutants of subtilisin E]

Ser 236, located in the surface of subtilisin E and at the end of alpha-helex with Ser221, is far from the active center (Asp32, His64, Ser221). The replacement of Ser236 with Cys via directed-mutagenesis should effect protease activity insignificantly and may be able to improve the stability of enzyme due to the potency to form disulfide across two molecules. The results indicated that BP-1 (Ser236Cys) was found to gain 150% activity (Kcat/Km value) of the wild-type subtilisin E and 3-fold increase in stability in aqueous solution at pH7.4 and 50 degrees C, compared to the wild-type enzyme. However, further mutations on BP-1 to introduce Ala15Asp/Gly20His (BU-1) or Ser24His/Lys27Asp (BW-1) was found negative effects on the activity and stability of subtilisin E.

Highlights of semi-synthetic developments from erythromycin A

Earlier semi-synthetic studies of erythromycin A culminated in the discovery of two successful second generation macrolide antibiotics, azithromycin and clarithromycin, for the treatment of community-acquired bacterial infections. More recent structural modifications of erythromycin A have resulted in the discovery of novel ketolide antibiotics and new motilide prokinetic agents. This review is an account of the semi-synthetic developments from erythromycin A by chemical transformations.

[Analysis of 1-(2,6-dichlorophenyl)-2-indolone and related materials by high performance liquid chromatography]

The separation of 1-(2,6-dichlorophenyl)-2-indolone (DCI) and related materials in the synthesis of medical intermediate DCI from 2, 6-dichlorophenol and phenylamine was investigated with high performance liquid chromatography under different chromatographic conditions. The results showed that DCI and related materials were in baseline separation by using CLC-CN(150 mm x 6.0 mm i.d., 7 microns) as column, MeOH-H2O(6:4, V/V) as mobile phase and a flow-rate at 1 mL/min. A rapid, accurate and reproducible HPLC method for determining DCI was developed. Fine and crude DCI samples were detected, results showed that N-(2,6-dichlorodiphenyl)-chloracetyl amide (CBCC) was the main impurity in fine sample, and CBCC and 2,6-dichlorodiphenylamine were the main impurities in the crude one.