Rae1 interaction with NuMA is required for bipolar spindle formation

In eukaryotic cells, the faithful segregation of daughter chromosomes during cell division depends on formation of a microtubule (MT)-based bipolar spindle apparatus. The Nuclear Mitotic Apparatus protein (NuMA) is recruited from interphase nuclei to spindle MTs during mitosis. The carboxy terminal domain of NuMA binds MTs, allowing a NuMA dimer to function as a "divalent" crosslinker that bundles MTs. The messenger RNA export factor, Rae1, also binds to MTs. Lowering Rae1 or increasing NuMA levels in cells results in spindle abnormalities. We have identified a mitotic-specific interaction between Rae1 and NuMA and have explored the relationship between Rae1 and NuMA in spindle formation. We have mapped a specific binding site for Rae1 on NuMA that would convert a NuMA dimer to a "tetravalent" crosslinker of MTs. In mitosis, reducing Rae1 or increasing NuMA concentration would be expected to alter the valency of NuMA toward MTs; the "density" of NuMA-MT crosslinks in these conditions would be diminished, even though a threshold number of crosslinks sufficient to stabilize aberrant multipolar spindles may form. Consistent with this interpretation, we found that coupling NuMA overexpression to Rae1 overexpression or coupling Rae1 depletion to NuMA depletion prevented the formation of aberrant spindles. Likewise, we found that overexpression of the specific Rae1-binding domain of NuMA in HeLa cells led to aberrant spindle formation. These data point to the Rae1-NuMA interaction as a critical element for normal spindle formation in mitosis.

A method for measuring systolic and diastolic microcirculatory red cell flux within the canine myocardium

BACKGROUND

Knowledge of the patterns of movement of red cells during the cardiac cycle in the microcirculation within the contracting myocardium is largely unknown. We describe a method of making such measurements in the canine myocardium using the technique of laser Doppler velocimetry.

METHODS

A lensed 100 microm fiber-optic probe was inserted into the beating myocardium at various sites. Using an ultra-stable laser and achieving measurement stability by heterodyning the laser light and reflected light from the tissue, it was possible to obtain a stable high quality measurement of predominately red cell movement in the microcirculation.

RESULTS

Unique regional patterns of red cell movement within the myocardium were observed. Epicardial flux was continuous with peaks while endocardial flux was predominately diastolic. Stopping flow in the epicardial artery for 5-6 s demonstrated that red cell movement continues in the microcirculation with some reduction followed by a delayed reactive hyperemia. Modeling demonstrates an important role for the small coronary veins in control of microcirculatory red cell movement.

CONCLUSIONS

It is possible using laser Doppler velocimetry to measure red blood cell flux in the beating canine myocardium. Such measurements demonstrate a high degree of complexity which is not reflected in epicardial coronary arterial or venous flow.

Treatment of diffuse proliferative lupus glomerulonephritis: a comparison of two cyclophosphamide-containing regimens

Cyclophosphamide (CYC) has proven beneficial in preserving renal function in patients with lupus with diffuse proliferative glomerulonephritis (DPGN). However, the optimal route of CYC administration is unknown because direct comparative studies are unavailable. In this open study, we compared the renal outcome of two historical cohorts of patients with diffuse proliferative lupus nephritis (World Health Organization classes IVa and IVb) treated with either intravenous (IV) pulse CYC (group A; n = 22) or sequential oral CYC followed by azathioprine (AZA; group B; n = 21) and followed up prospectively. Both groups of patients had similar clinical, biochemical, and renal parameters at baseline. At 24 months posttreatment, significant improvements in proteinuria, creatinine clearance, serum albumin level, and lupus serological results were evident in both groups. Compared with patients in group A, patients in group B had more complete or partial remission (90% versus 73%) and less risk for treatment failure (5% versus 14%), renal flares (5% versus 14%), and doubling of creatinine levels (5% versus 9%), but the difference was not statistically significant. However, patients treated with oral immunosuppression had an insignificant increase in rates of herpes zoster infection (19% versus 9%) and menstrual disturbance (50% versus 29%). We conclude that sequential oral immunosuppression with CYC and AZA tended to have better efficacy than IV pulse CYC in the treatment of lupus DPGN but was associated with more toxicities. Additional randomized trials involving a larger cohort of patients with a longer period of observation are necessary.

Use of exogenous estrogens in systemic lupus erythematosus

OBJECTIVE

To review the current literature on the safety of using exogenous estrogens in patients with systemic lupus erythematosus (SLE).

METHOD

A MEDLINE search for articles published between 1970 and 2000 regarding the relationship between estrogens and SLE was performed. Emphasis was put on human studies, treatment trials, and epidemiologic surveys.

RESULTS

The use of exogenous estrogens in healthy women increases the risk of SLE development. For patients with established SLE, a hypoestrogenemic state appears to be protective against severe flares, whereas exogenous estrogen administration or hyperestrogenemia induced by hormonal manipulation may exacerbate the disease in certain individuals. Both the use of oral contraceptives and the use of hormonal replacement therapy (HRT) increase the chance of venous thromboembolism. The presence of antiphospholipid antibodies may aggravate the risk of thrombosis in SLE. In retrospective studies, HRT appears to be well tolerated in postmenopausal SLE patients.

CONCLUSIONS

There are no prospective data that show a deleterious effect of exogenous estrogens on disease activity in human SLE. Oral contraceptives may be considered for patients with SLE in the absence of active nephritis or antiphospholipid antibodies. The slight increase in venous thromboembolic risk should not be the chief deterrent to the use of HRT in postmenopausal SLE patients, considering its various health benefits.

Neuropsychiatric manifestations and their clinical associations in southern Chinese patients with systemic lupus erythematosus

OBJECTIVE

To study the neuropsychiatric (NP) manifestations in a large cohort of southern Chinese patients with systemic lupus erythematosus (SLE) according to the new 1999 American College of Rheumatology (ACR) case definitions and their clinical associations.

METHOD

Patients with SLE who were followed from 1984 to 2000 were retrospectively reviewed. Patients with NP manifestations were ascertained and classified by at least 2 rheumatologists, with the collaboration of neurologists and psychiatrists. The association of NP manifestations with other clinical features and autoantibodies was studied by statistical analysis.

RESULTS

Five hundred eighteen patients with SLE were studied. The female to male ratio was 7.8 to 1 and the mean age of disease onset was 29.5 +/- 12.0 years (range 9-80). The mean duration of followup was 7.3 +/- 6.7 years (range 0.3-23.0). Ninety-six patients (19%) had 133 NP events and the mean number of events per patient-year of followup was 0.035. In decreasing order of frequency. these events were: seizure disorder (28%), cerebrovascular disease (19%), acute confusional state (14%), psychosis (11%), myelopathy (8%), mood disorder (6%), headache (4%), movement disorder (2%), cranial neuropathy (3%), demyelinating syndrome (1.5%), anxiety disorder (1.5%), mononeuritis multiplex/mononeuropathy (1.5%), aseptic meningitis (1%), and polyneuropathy (1%). Cognitive dysfunction was not classified because of the lack of standard neuropsychological testing for every patient. Univariate analysis revealed that NP-SLE was associated with a positive lupus anticoagulant (LAC) (p = 0.001), a strongly positive IgG anticardiolipin (aCL) (p = 0.01). leukopenia (p = 0.01), lymphopenia (p = 0.03), thrombocytopenia (p = 0.03), and pulmonary involvement (p = 0.03). Multivariate analysis showed that a strongly positive IgG aCL [RR 3.1 (1.3-7.7), p = 0.01] and a history of cyclophosphamide treatment [RR 4.3 (2.1-9.0), p < 0.001] were independently associated with NP manifestations in our cohort. Among the NP features, cerebrovascular disorder was particularly associated with the presence of LAC [OR 3.3 (1.4-8.0), p = 0.01] and a strongly positive IgG aCL [OR 3.1 (1.1-8.2), p = 0.031].

CONCLUSION

The point prevalence of overt NP manifestations in our cohort of patients with SLE was 19%. This percentage was likely higher if subtle cognitive dysfunction was included. Seizure and cerebrovascular disorders were the most common NP features. The presence of antiphospholipid antibodies was significantly associated with NP manifestations, especially cerebrovascular disorders.

Pregnancy in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that predominantly affects women of reproductive age. Pregnancy and its outcome is a major concern to most SLE patients. Queries regarding the risk of disease flares during pregnancy, chance of fetal loss, and the safety of various drugs are often raised. With the improvement in the understanding of the pathogenesis of SLE and the judicious use of immunosuppressive drugs, better disease control can now be achieved and SLE patients should not be deprived of the opportunity for bearing children. Prepregnancy counselling and close collaboration with other specialists such as the obstetricians and the perinatologists is essential in optimising the maternal and fetal outcome in lupus pregnancies. In this review, important issues regarding the fertility rate, optimal timing of conception, risk of disease flares during lupus pregnancy, pregnancy course, fetal outcome, safety of various drugs used for disease control during pregnancy and lactation, and contraceptive advice are discussed.

Expression of epidermal growth factor in transgenic mice causes growth retardation

The epidermal growth factor (EGF) family of peptides signals through the erbB family of receptor tyrosine kinases and plays important roles in development and tumorigenesis. Both EGF and transforming growth factor (TGF)-alpha only bind to erbB1 and activate it. The precursor of EGF is distinct from that of TGF-alpha in having eight additional EGF-like repeats. We have recently shown that the EGF precursor without these repeats is biologically active and leads to hypospermatogenesis in transgenic mice. Here we present evidence that the growth of transgenic mice widely expressing this engineered EGF precursor is also stunted. These mice were consistently born at half the normal weight and reached almost 80% of normal weight at adulthood. The mechanism involved a reduction of serum insulin-like growth factor-binding protein-3. Chondrocyte development in the growth plate was affected, and osteoblasts accumulated in the endosteum and periosteum. Besides these novel findings on the in vivo effects of EGF on bone development, we observed no sign of tumor formation in our transgenic animals. In contrast to previous reports on TGF-alpha transgenic mice, we show that the biological functions of EGF and TGF-alpha are clearly distinct.

Efficacy of mycophenolate mofetil in patients with diffuse proliferative lupus nephritis. Hong Kong-Guangzhou Nephrology Study Group

BACKGROUND

The combination of cyclophosphamide and prednisolone is effective for the treatment of severe lupus nephritis but has serious adverse effects. Whether mycophenolate mofetil can be substituted for cyclophosphamide is not known.

METHODS

In 42 patients with diffuse proliferative lupus nephritis we compared the efficacy and side effects of a regimen of prednisolone and mycophenolate mofetil given for 12 months with those of a regimen of prednisolone and cyclophosphamide given for 6 months, followed by prednisolone and azathioprine for 6 months. Complete remission was defined as a value for urinary protein excretion that was less than 0.3 g per 24 hours, with normal urinary sediment, a normal serum albumin concentration, and values for serum creatinine and creatinine clearance that were no more than 15 percent above the base-line values. Partial remission was defined as a value for urinary protein excretion that was between 0.3 and 2.9 g per 24 hours, with a serum albumin concentration of at least 30 g per liter.

RESULTS

Eighty-one percent of the 21 patients treated with mycophenolate mofetil and prednisolone (group 1) had a complete remission, and 14 percent had a partial remission, as compared with 76 percent and 14 percent, respectively, of the 21 patients treated with cyclophosphamide and prednisolone followed by azathioprine and prednisolone (group 2). The improvements in the degree of proteinuria and the serum albumin and creatinine concentrations were similar in the two groups. One patient in each group discontinued treatment because of side effects. Infections were noted in 19 percent of the patients in group 1 and in 33 percent of those in group 2 (P = 0.29). Other adverse effects occurred only in group 2; they included amenorrhea (in 23 percent of the patients), hair loss (19 percent), leukopenia (10 percent), and death (10 percent). The rates of relapse were 15 percent and 11 percent, respectively.

CONCLUSIONS

For the treatment of diffuse proliferative lupus nephritis, the combination of mycophenolate mofetil and prednisolone is as effective as a regimen of cyclophosphamide and prednisolone followed by azathioprine and prednisolone but is less toxic.

Composite autogenous bone and demineralized bone matrices used to repair defects in the parietal bone of rabbits

We compared the amount of new bone produced by endochondral and intramembranous autogenous bone grafts in the presence of demineralized bone matrices (DBMs) prepared from intramembranous bone (DBM(IM)) or endochondral bone (DBM(EC)). Thirty-five bone defects were created in the parietal bone of 20 New Zealand White rabbits. In the experimental groups, 5 defects were grafted with endochondral bone, 5 with endochondral bone mixed with DBM(IM)) (EC-DBM(IM)), 5 with intramembranous bone mixed with DBM(IM)(IM-DBM(IM)) and 6 with endochondral bone mixed with DBM(EC)(EC-DBM(EC)). In the control groups, 10 defects were left alone (passive control) and 4 were grafted with rabbit skin collagen (active control). They were all killed on day 14 and the defects were prepared for histological study. Serial sections were cut across the whole defect. Quantitative analyses were made on 202 sections of the experimental groups by image analysis. A total of 414%, 708%, and 85% more new bone was formed in defects grafted with composite EC-DBM(IM), IM-DBM(IM)and EC-DBM(EC), respectively, than those grafted with endochondral bone alone (P<0.001). No bone was formed in either passive or active controls. In conclusion, demineralized bone matrices, particularly those derived from intramembranous bone, have extremely high osteoinductive properties and greatly improve the integration of autogenous bone grafts in the skull.

Effect of calcitriol on bone mineral density in premenopausal Chinese women taking chronic steroid therapy. A randomized, double blind, placebo controlled study

OBJECTIVE

To study the effect of chronic steroid therapy on bone mineral density (BMD) in premenopausal women with normal menstrual cycles and its treatment.

METHODS

A double blind placebo controlled study to evaluate 81 premenopausal women with systemic lupus erythematosus (SLE), aged 31.1 +/- 6 years, taking chronic steroid therapy, with a mean cumulative prednisone dose of 28 +/- 16.2 g. They were randomly allocated to 3 groups: Group 1: 0.5 microg calcitriol and 1200 mg calcium daily; Group 2: 1,200 mg calcium and placebo calcitriol; and Group 3: both placebo calcitriol and placebo calcium.

RESULTS

Baseline T score at the lumbar spine was > -1 in 56.8% and < -2.5 in 3.7% of the patients. At the end of 2 years, patients in the calcitriol group exhibited a significant increase of 2.1 +/- 2.4% in BMD at the lumbar spine compared to baseline value (p < 0.05). This change was not significantly different from the respective change in either calcium or placebo group (0.4 +/- 2.9% and 0.3 +/- 3.5%, respectively). No significant changes were observed in any treatment group in BMD at the hip or radius. Alkaline phosphatase increased both in the placebo (baseline: 57.5 +/- 17.5 IU/I; year 2: 60.9 +/- 15.3 IU/A) and the calcium group (baseline: 53.6 +/- 16.6 IU/I; year 2: 59.0 +/- 22.8 IU/1), but this increase reached statistical significance only in the calcium group, while the same variable remained stable in the calcitriol group (baseline: 53.9 +/- 14.1 IU/I; year 2: 54.6 +/- 12.3 IU/I).

CONCLUSION

Premenopausal women with SLE taking prolonged steroid therapy had lower BMD but showed no significant bone loss over the 2 year study period. The beneficial effect of calcitriol treatment in these premenopausal women was small, at least when it was instituted late in the course of steroid therapy.

Overexpression of epidermal growth factor induced hypospermatogenesis in transgenic mice

The in vivo role of epidermal growth factor (EGF) is not well defined even though its effects on culture cells were well studied. To understand the developmental, physiological, and pathological roles of EGF, we have generated transgenic mice widely expressing human EGF with the use of the beta-actin promoter. EGF and transforming growth factor alpha (TGFalpha) bind with equal affinity to the EGF receptor, a transmembrane tyrosine kinase, to trigger various biological responses. EGF and TGFalpha signaling are implicated in the development of the reproductive system. EGF also plays a physiological role in reproduction. Removal of the salivary gland in rodents, which reduces circulating EGF, reduces spermatogenesis, which can be corrected by EGF replacement. Here we show that in our transgenic males, only few post-meiosis II gametes were found, and the mice were sterile. This resembles a common cause of infertility in humans. Furthermore, the transgenic males had reduced serum testosterone. Our findings contrast the previous report on transgenic mice overexpressing TGFalpha in testis, which showed normal spermatogenesis. These data suggest that EGF is the active ligand for EGF receptor reported in germ cells, and proper EGF expression is important for completion of spermatogenesis.

An efficient method of generating transgenic mice by pronuclear microinjection

Genetic transformation of mice using pronuclear microinjection was demonstrated by a number of groups in rapid succession in the early 1980's. Since that time, studies using transgenic animals have produced major advances in biomedical sciences and molecular genetics. More important, it is possible to study the molecular basis for tissue and stage-specific expression of genes. We recently used this method to generate transgenic mice. DNA fragment (transgene) was injected into the pronucleus of one-cell embryos. We describe this simplified protocol, which is reliable. With the use of buffered medium M2 for the whole process, it is not mandatory to have a CO2 incubator.

Safety of disease modifying anti-rheumatic agents in rheumatoid arthritis patients with chronic viral hepatitis

OBJECTIVE

To examine the safety of the use of disease modifying anti-rheumatic drugs (DMARDs) in rheumatoid arthritis (RA) patients with chronic viral hepatitis (CVH).

METHODS

Records of 600 Chinese patients satisfying the ARA criteria for RA in two rheumatology centers were reviewed. Patients with CVH were studied. Liver enzymes were checked before (baseline) and during DMARD use at 3-month intervals or more frequently if necessary. Drug-episodes (D-Ep), defined as the continuous use of DMARD, singly or in combination, for more than 6 months in a patient, were analysed. Changes in serum liver alanine transaminase (ALT) levels as multiples of the upper range of normal were taken to reflect the severity of hepatotoxicity. Changes of ALT to > or = 1.5 times the upper range of normal if they were measured at baseline or > or = 2 times the upper range of normal if they were measured during and after the use of DMARD were considered as abnormal. Control patients included those with CVH alone (n = 623) or RA without CVH (n = 62) matched for age, sex and D-Ep.

RESULTS

30 RA patients were found to have concomitant CVH. One patient was excluded because of use of NSAID alone (n = 1). Among the 29 patients, 23 were HBsAg +ve and 6 were anti-HCV Ab +ve. A total of 47 D-Ep were analysed. 20/47 (42.6%) of D-Ep in 16/29 (55.2%) RA + CVH patients developed abnormal ALT levels after a mean 1.9-year duration of DMARD use. This was statistically significant when compared with 13/94 (13.8%) of D-Ep which ended with abnormal ALT levels in 13/62 (21%) patients with RA alone (p < 0.0001 for D-Ep which ended up with abnormal ALT, and p < 0.02 for the number of patients who developed abnormal ALT) and 128/623 (20.5%) patients with CVH alone (p < 0.005). 53% (9/17) of hydroxychloroquine (HCQ) D-Ep were associated with an abnormal outcome. Corresponding figures for sulphasalazine (SAZP) and oral or intramuscular gold preparations were 55.6% (5/9) and 0% (0/3) respectively. Two patients on methotrexate, used either singly or in combination, had normal ALT levels throughout the study period. One patient on azathioprine developed reactivation of hepatitis B infection. When D-Ep of the RA + CVH group were further analysed, 16/43 (37.2%) and 4/4 (100%) D-Ep which started with normal and abnormal baseline ALT respectively developed further liver enzyme derangement.

CONCLUSION

The use of DMARD in RA + CVH patients is associated with a high incidence of hepatotoxicity. The effect is likely to be synergistic. This includes drugs such as HCQ, which is generally believed to be less hepatotoxic.

Semiquantitative immunoblots of membrane protein-epidermal growth factor

Membrane proteins or cytokines are sometimes difficult to isolate and purify. Our group recently concentrated on epidermal growth factor (EGF) protein expression studies. Mature EGF was initially identified from mouse submaxillary gland extract as a stimulator of eyelid opening and incisor eruption when injected into newborn mice and rats. The EGF precursor is a transmembrane protein with eight additional EGF-like repeats. Our previous study has shown that the EGF precursor without these eight EGF-like repeats (hEGF) was biologically active. Here, we introduce a modified method for rapid detection of hEGF. The membranous protein was directly extracted from various organs of transgenic mice (including the submandibular gland, kidney, liver, heart, and testis) with two different buffers and easily detected by semiquantitative immunoblotting.

A prospective study of survival and prognostic indicators of systemic lupus erythematosus in a southern Chinese population

OBJECTIVES

To study the survival rate and prognostic indicators of systemic lupus erythematosus (SLE) in a southern Chinese population.

METHODS

One hundred and eighty-six patients with SLE diagnosed between 1992 and 1999 were prospectively followed. Clinical features at presentation, subsequent evolving features, autoantibody profile, damage scores and mortality data were obtained. Prognostic factors for survival were studied by statistical analysis.

RESULTS

One hundred and sixty-three female and 23 male SLE patients were studied. The female to male ratio was 7.1 to 1 and the mean age at presentation was 33.6 yr (range 12-75). The mean disease duration was 45.2 months. At diagnosis, arthritis, malar rash and alopecia were the commonest features. During follow-up, the prevalence of nephritis, arthritis, photosensitivity and haematological disease increased significantly. Thirty-one per cent of the patients had organ damage at the time of data analysis and renal disease was the commonest cause. Logistic regression revealed that central nervous system disease, discoid lesions and treatment with high-dose steroid were independent predictors for damage. Nine patients died during the study period (three of disease-related complications and six of infections). The 3-, 5-, and 7-yr survival rates of our cohort were 97, 93 and 93%, respectively. Cox regression analysis revealed that thrombocytopenia and high-dose steroid treatment were independent risk factors for mortality.

CONCLUSIONS

The survival of SLE in our southern Chinese patients is similar to that of the Caucasian series reported in the 1990s. Although nephritis contributes to organ damage, it is not a major determinant for survival. Infection remains the commonest cause of death. High-dose steroid treatment and thrombocytopenia are independent risk factors for mortality. Judicious use of immunosuppressive agents is necessary to improve the short-term survival of SLE.

Intestinal pseudo-obstruction in systemic lupus erythematosus: an uncommon but important clinical manifestation

OBJECTIVES

To document intestinal pseudo-obstruction (IpsO) as a recognised clinical manifestation of systemic lupus erythematosus (SLE) and a possible new clinical entity with its apparent association with ureterohydronephrosis.

METHODOLOGY

We report six lupus patients who presented with IpsO and review 12 other cases from an English literature search. IpsO is defined as the presence of clinical features suggestive of intestinal obstruction but without organic obstruction, namely absence of bowel sounds, presence of multiple fluid levels on plain abdominal X-rays and exclusion of organic obstruction by imaging or surgical procedure. Other clinical characteristics related to the underlying lupus, serological and histological findings, treatment modalities and outcomes of these patients were reviewed.

RESULTS

All 18 patients fulfilled the ACR revised classification criteria for SLE. None showed any clinical features of scleroderma or overlap syndrome. The mean age of onset of IpsO was 29.0 (15-47) y. The female to male ratio was 16:2. Nine patients had IpsO as the initial presentation of their underlying lupus. Coexisting lupus involvement of other organ systems included glomerulonephritis (n=7), thrombocytopenia (n=5) and cerebral lupus (n=3). The serology data and autoantibody profile of some of the previously reported patients were incomplete. In our series, anti-Ro antibody was positive in 5/6 while anti-RNP was found in 1/6 patients only. All our patients had active lupus serology at presentation. 17/18 patients required the use of high dose systemic corticosteroid therapy while one patient responded to topical adrenocorticotrophin hormone treatment. Response was good and was observed early after commencement. Azathioprine was used as maintenance therapy in 6/18 patients with good effects. An apparent association with the presence of bilateral ureterohydronephrosis was found in 12/18 patients. These patients presented with dysuria without positive bacterial culture though features of chronic interstitial cystitis were not invariably found in these patients.

CONCLUSION

IpsO is an uncommon but important manifestation of SLE. The underlying pathology is not fully understood but it may be related to immune complex deposition. The finding of coexisting ureterohydronephrosis suggests that there may also be a central smooth muscle motility problem of neuropathic or myogenic pathophysiology which may or may not be secondary to vasculitis. Early recognition and treatment of IpsO in SLE is important.

Do flares of systemic lupus erythematosus decline after menopause?

OBJECTIVE

To study whether flares of SLE decline after menopause.

METHOD

34 postmenopausal SLE patients with premenopausal disease onset were studied. The frequency and severity of flares before and after menopause was compared. 17 postmenopausal onset SLE patients were also included for comparison.

RESULT

Flares in postmenopausal SLE patients decreased significantly after menopause (total No. of flares/patient-year before and after menopause were 0.50+/-0.10 and 0.14+/-0.05, respectively, p = 0.002). The frequency and proportion of severe flares also dropped significantly. The rate and magnitude of postmenopausal flares in these patients were similar to those of the postmenopausal onset SLE patients, a subset known to run a more benign course.

CONCLUSIONS

SLE flares less frequently and seriously after menopause. While this may suggest a protective role of hypoestrogenemia against lupus flares, the contribution of other factors like disease duration and effective treatment to this postmenopausal decline of flares cannot be separated from menopause per se. Further studies are needed.

Osteopenia in young hypogonadal women with systemic lupus erythematosus receiving chronic steroid therapy: a randomized controlled trial comparing calcitriol and hormonal replacement therapy

OBJECTIVE

To evaluate the efficacy of calcitriol and hormonal replacement therapy (HRT) in the treatment of steroid-induced osteoporosis in hypogonadal women.

METHODS

We studied 28 young patients (aged 37 +/- 6 yr) with systemic lupus erythematosus (SLE) on chronic steroid therapy for 130 +/- 22 months and requiring more than 10 mg/day prednisone. They were amenorrhoeic for more than 2 yr with proven ovarian failure. All had osteopenia with a T score at L2-4 of less than -1. They were randomized to receive HRT (conjugated oestrogen 0.625 mg daily from day 1 to day 21 plus medroxyprogesterone acetate 5 mg daily days 10-21) or calcitriol 0.5 microg daily. All received calcium carbonate 1 g/day.

RESULTS

There were no differences in the baseline demographic, bone mineral density (BMD) and biochemical data between the two groups. Lumbar spine BMD increased by 2.0 +/- 0.4% after 2 yr with HRT (P<0.05), but reduced by 1.74 +/- 0.4% (P<0.05) with calcitriol treatment. No change was seen at the distal one-third radius with HRT treatment but significant bone loss (2.3 +/- 1.4%, P<0.02) was observed with calcitriol therapy. BMD at the hip did not change in both groups. Comparing both treatment groups, significant differences in the BMD at the spine (P<0.03) and radius (P<0.05) were seen at the end of 2 yr. The changes in urinary n-telopeptide excretion but not serum osteocalcin at 6 months and 12 months were inversely correlated with the changes in lumbar spine BMD at 24 months. HRT did not cause an adverse effect on SLE disease activity.

CONCLUSION

HRT but not calcitriol could prevent bone loss in young hypogonadal women on chronic steroid therapy.

Bone induction using autogenous bone mixed with demineralised bone matrices

The aim of the present study was to examine the healing of endochondral (EC) autogenous bone grafts in the presence of demineralised bone matrix prepared from intramembranous bone (DBMIM), or prepared from endochondral bone (DBMEC) using quantitative analysis. Thirty bone defects were created on the parietal bone of fifteen New Zealand White rabbits. In the experimental groups, five defects were grafted with EC bone, five defects were grafted with EC bone mixed with DBMIM (EC-DBMIM) and six defects were grafted with EC bone mixed with DBMEC (EC-DBMEC). In the control groups, ten defects were left empty (passive control) and four defects were grafted with rabbit skin collagen (positive control). They were all sacrificed at day fourteen post grafting, and the defects were prepared for histological analysis. Serial sections were cut across the whole defect. Quantitative analysis was performed on 152 sections of the experimental groups by image analysis. Four hundred and fourteen per cent more new bone was formed in defects grafted with composite EC-DBMIM than those grafted with EC bone alone (p < 0.001). Eighty-five per cent more new bone was formed in defects grafted with composite EC-DBMEC than those grafted with EC bone alone (p < 0.001). No bone was formed in either passive or positive controls. In conclusion, DBM, especially DBMIM, have extremely high osteoinductive properties and greatly enhance the integration of EC bone grafts with defects created in IM bone.

A simple and rapid method for isolating myelin basic protein

The conduction of impulses along axons of nerves is facilitated by the myelin sheath, composed of proteins and lipid. Myelin basic proteins (MBPs) are extrinsic membrane proteins that play an important role in the structural organization of the myelin sheath. In the central nervous system, MBPs account for 30-40% of total protein. The traditional method of MBP isolation involves the use of chloroform-ethanol, which would destroy the native form of MBP. A modified method for maintaining its native form was developed. The white matter of porcine brain was directly extracted by buffers containing different concentrations of sodium chloride owing to MBP solubilized at high concentration of NaCl. The MBP was further purified by cation exchange chromatography and buffers containing glycine and salts. Purified MBP were consistently obtained by this method.

Reduced in vitro production of interferon-gamma, interleukin-4 and interleukin-12 and increased production of interleukin-6, interleukin-10 and tumour necrosis factor-alpha in systemic lupus erythematosus. Weak correlations of cytokine production with disease activity

Production of cytokines in unstimulated and mitogen-stimulated cultures were evaluated by ELISPOT in 34 SLE patients with low to moderate disease activity and 23 healthy controls. Significantly reduced production of IFN gamma, IL4 and IL12 and significantly increased production of IL6, IL10 and TNF alpha were found in patients with SLE. Regression analysis revealed that production of all six cytokines tended to decrease with increasing disease activity, but negative correlation with SLEDAI was significant (p < 0.05) only for PHA-stimulated IL4, unstimulated and PHA-stimulated IL10 and SAC-stimulated IL6. Negative correlation of stimulated and unstimulated IL6 and TNF alpha production with anti-DNA antibody levels were also significant.