Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales^1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare⁴ in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet⁵, plasma instabilities^6,7 or orbital motion in an accretion disc^7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. ⁹). BL Lac, the prototype of a subclass of blazars¹⁰, is powered by a 1.7 × 10⁸ M_Sun (ref. ¹¹) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. ¹²)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities⁶ near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

Effect of Black Tea Infusion on Physicochemical Properties, Antioxidant Capacity and Microstructure of Acidified Dairy Gel during Cold Storage

The impacts of black tea infusion on physicochemical properties, antioxidant capacity and microstructure of stirred acidified dairy gel (ADG) system have not been fully explored. These impacts were studied during a 28-day cold storage (4 °C) period to explore the feasibility and technical boundaries of making acidified dairy gels in which black tea infusion (BTI) is incorporated. Reconstituted skim milks containing different proportions of BTI were acidified by GDL (glucono-δ-lactone) at 35 °C for making ADG systems. Both textural properties and structural features were characterized; antioxidant capacity was determined through three assays. They are (1) free radical scavenging ability by DPPH (2,2-diphenyl-1-picrylhydrazyl) assay; (2) ABTS [2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid)] assay and (3) ferric reducing antioxidant power (FRAP) assay. The microstructure of the ADGs was observed using SEM (scanning electron microscopy) and CLSM (confocal laser scanning microscopy). Results showed that BTI significantly increased the antioxidant capacity of the gel systems and the gel containing 15% BTI was as stable as the control gel in terms of syneresis rate. However lower phase stability (higher syneresis rate) was observed in the ADG with a higher portion of BTI (30% to 60%). The microstructure of the ADGs observed may explain to the phase stability and textural attributes. The results suggested that tea polyphenols (TPs) improved antioxidant capacity in all samples and the interactions between BTI and dairy components significantly altered the texture of ADGs. Such alterations were more pronounced in the samples with higher proportion of BTI (60%) and/or longer storage time (28 days).

Cirrhosis in Hemochromatosis: Independent Risk Factors in 368 HFE p.C282Y Homozygotes

INTRODUCTION AND AIM

We sought to identify independent risk factors for cirrhosis in HFE p.C282Y homozygotes in a cross-sectional study.

MATERIAL AND METHODS

We evaluated 368 p.C282Y homozygotes who underwent liver biopsy and compared characteristics of those with and without cirrhosis. We performed multivariable logistic regression on cirrhosis with: age; sex; race/ethnicity; diabetes; blood pints/units donated voluntarily; erythrocyte pints/units received; iron supplement use; alcohol intake, g/d; body mass index, kg/m2; swollen/tender 2nd/3rd metacarpophalangeal joints; elevated alanine aminotransferase; elevated aspartate aminotransferase; steatosis/fatty liver; iron removed by phlebotomy, g; and GNPAT p.D519G positivity.

RESULTS

Mean age of 368 participants (73.6% men) was 47 ± 13 (standard deviation) y. Cirrhosis was diagnosed in 86 participants (23.4%). Participants with cirrhosis had significantly greater mean age, proportion of men, diabetes prevalence, mean daily alcohol intake, prevalence of swollen/ tender 2nd/3rd metacarpophalangeal joints, mean serum ferritin, elevated alanine aminotransferase, elevated aspartate aminotransferase, and mean iron removed; and significantly fewer mean blood pints/units donated. GNPAT p.D519G positivity was detected in 82 of 188 participants (43.6%). In a multivariable model for cirrhosis, there were four significant positive associations: age (10-y intervals) (odds ratio 2.2 [95% confidence interval 1.5, 3.3]); diabetes (3.3; [1.1, 9.7]); alcohol intake (14 g alcohol drinks/d) (1.5 [1.2, 1.8]); and iron removed, g (1.3 [1.2, 1.4]). There was no statistical evidence of two-way interactions between these variables.

CONCLUSION

In conclusion, cirrhosis in HFE p.C282Y homozygotes is significantly associated with age, diabetes, daily alcohol intake, and iron removed by phlebotomy, taking into account the effect of other variables.

Fiber inline Mach-Zehnder interferometer based on femtosecond laser inscribed waveguides

A new type of Mach-Zehnder interferometer device based on in-fiber optical waveguides, fabricated by direct femtosecond laser pulse inscription in a single-mode fiber has been demonstrated and successfully employed for temperature and strain measurement. The in-fiber waveguide can couple the light out from the fiber core and guide it along the cladding region before directing it back into the fiber core. Such an inner structured interferometer device is compact and robust, can be constructed in a flexible and precisely controlled manner, and hence is expected to have many potential applications.

Multimode fiber tip Fabry-Perot cavity for highly sensitive pressure measurement

We demonstrate an optical Fabry-Perot interferometer fiber tip sensor based on an etched end of multimode fiber filled with ultraviolet adhesive. The fiber device is miniature (with diameter of less than 60 μm), robust and low cost, in a convenient reflection mode of operation, and has a very high gas pressure sensitivity of −40.94 nm/MPa, a large temperature sensitivity of 213 pm/°C within the range from 55 to 85 °C, and a relatively low temperature cross-sensitivity of 5.2 kPa/°C. This device has a high potential in monitoring environment of high pressure.

Functional and association studies of the cholesteryl ester transfer protein (CETP) gene in a Wannan Black pig model

Some polymorphisms of the human CETP gene are causally and significantly associated with serum lipids levels; however, the information regarding this gene in pigs is sparse. To evaluate the effects of CETP on blood lipid traits and fat deposition in pig, porcine CETP tissue expression patterns were observed by quantitative real-time polymerase chain reaction (qPCR) first. High expression was detected in liver, spleen, gluteus medius (GM) muscle and backfat. A de novo polymorphism (AF333037:g.795C>T) in the intron 1 region of porcine CETP was identified. This polymorphism was further genotyped by direct sequencing of the PCR products of 390 Wannan Black pigs, a Chinese native breed population. Association analyses at 45 and 300 days of age revealed highly significant associations between CETP genotypes and serum lipid traits. Furthermore, this polymorphism was proved to be associated with differences in liver CETP mRNA levels: pigs at 300 days of age with the TT genotype had higher levels than did those with other genotypes (P = 0.021). Additionally, analysis at 300 days of age showed that GM CETP mRNA expression correlated positively with serum lipids levels as well as with carcass backfat thickness and intramuscular fat content in GM. These results indicate that CETP is involved in serum, adipose and muscle lipid metabolism in pigs. The mechanisms underlying such relationships and their functional implications are worthy of further research.

Correlation of endogenous hormonal levels, fibroglandular tissue volume and percent density measured using 3D MRI during one menstrual cycle

BACKGROUND

We measured breast density (BD) on MRI and correlated with endogenous hormonal levels.

PATIENTS AND METHODS

Twenty-four premenopausal women received four weekly breast MRI. A blood sample was collected on the same day of MRI. BD was measured using a computer-based algorithm. The generalized estimation equation method was applied to model mean fibroglandular tissue volume (FV) and mean percent density (PD) from predictor variables including estradiol, progesterone, and week during a cycle.

RESULTS

In week 3, a borderline significant correlation between estradiol and PD (r = 0.43, P = 0.04), estradiol and FV (r = 0.40, P = 0.05) and between progesterone and FV (r = 0.42, P = 0.04) was noted. The FV and PD measured in weeks 4 and 1 were higher than in weeks 2 and 3, adjusted for variation in endogenous estradiol and progesterone, indicating that the hormone change could not account for the changes in density. No lag effect of endogenous hormone on the change of FV or PD was noted (all P-values > 0.05).

CONCLUSIONS

Our results showed that BD is not strongly associated with the endogenous hormone. Their association with breast cancer risk was likely coming from different mechanisms, and they should be considered as independent risk factors.

Visfatin: A Potential Therapeutic Target for Rheumatoid Arthritis

Rheumatoid arthritis (RA) is usually a chronic, systemic inflammatory disorder primarily targeting the synovium and articular cartilage. It is incurable, costly and responds poorly to treatment. Methotrexate alone or in combination with conventional and/or biological disease-modifying antirheumatic drugs (DMARDs) is often used to induce remission of active disease. The effectiveness of treatment is, however, limited and most patients develop chronic disability and require total knee arthroplasty or total hip replacement. Emerging therapies targeting specific cytokines and growth factors in the RA inflammatory cascade offer potent new means of modifying disease activity. Recently, increased concentrations of adipokines, including visfatin, mainly produced by adipocytes in serum and joint synovial fluid, were found in RA patients. Visfatin has important pro-inflammatory and catabolic roles in RA pathogenesis and is now being studied as a potential therapeutic target for RA. Here we discuss the relationship between visfatin and RA and its potential as a therapeutic target for RA.

Effects of alginate coated on PLGA microspheres for delivery tetracycline hydrochloride to periodontal pockets

The effects of alginate coated on tetracycline (Tc) loaded poly (D, L-lactic-co-glycolic acid) (PLGA) microspheres fabricated by double emulsion solvent evaporation technique for local delivery to periodontal pocket were investigated. Alginate coated PLGA microspheres showed smoother surface but enlarged their particle sizes compared with those of uncoated ones. In addition, alginate coated microspheres enhanced Tc encapsulation efficiency (E.E.) from 11.5 +/- 0.5% of uncoated ones to 17.9 +/- 0.5%. Moreover, all of the coated PLGA microspheres even fabricated at different conditions could prolong Tc release from 9-12 days with 50% or higher in cumulative release of Tc compared with those of uncoated ones. The swelling ratios of PLGA microspheres for alginate coated or uncoated ones, one of the possible mechanisms for enhancing Tc release for the coated ones, were measured. The results showed that 20% or higher in swelling ratio for the coated microspheres at the earlier stage of hydration (e.g. < or = 24 h) could be an important factor to result in high Tc release compared to the uncoated ones. In conclusion, alginate coated Tc loaded PLGA microspheres could enhance Tc delivery to periodontal pocket by enhancing drug encapsulated efficiency, released quantities and sustained release period compared with uncoated ones.

Assessment of American College of Rheumatology quality criteria for rheumatoid arthritis in a pre-quality criteria patient cohort

OBJECTIVE

To evaluate the American College of Rheumatology (ACR) starter set of quality measures for rheumatoid arthritis (RA) in an actual patient cohort that preceded publication of the quality measures.

METHODS

We retrospectively applied the 2006 ACR quality criteria to a prospectively studied cohort of 568 patients with RA treated by 1,932 unique physicians including 255 different rheumatologists between the years 1999 and 2003. Data on performance were obtained from self-report surveys and medical record review within 12 months.

RESULTS

At least 1 joint examination was performed in 98% of patients. Patient and physician global assessments were reported for 79% and 74% of patients, respectively. A total of 85% of patients received disease-modifying antirheumatic drugs (DMARDs). DMARD adjustments were made for 50% of patients in whom increasing disease activity was noted at least once and for 64% of patients in whom increasing disease activity was noted during 2 (of 4) 3-month periods within the year. Compared with self-report surveys, medical records substantially underreported performance on quality measures.

CONCLUSION

The ACR-endorsed quality measures for RA can be assessed using available data sources. When both self-report and medical record data are used, adherence rates, designed to serve as minimum standards of care, were moderate or high for most measures. Prior to using indicators to compare quality across groups, specific strategies for operationalizing measures and for using accurate data sources to assess adherence to the measures should be defined.

Application of explicit process of care measurement to rheumatoid arthritis: Moving from evidence to practice

OBJECTIVE

To construct quality measures with measurement validity and meaning for clinicians.

METHODS

We conducted a prospective cohort study of rates of change in disease-modifying antirheumatic drug (DMARD) and/or systemic corticosteroid drug or dose for 568 patients with rheumatoid arthritis (RA) across 6,159 clinical encounters within 12 months to examine how changes in clinical specifications change adherence.

RESULTS

Rates of DMARD change were sensitive to specifications regarding the intensity of disease activity (severe or moderate), duration of specified disease activity, and length of the observation period. Over 12 months, the proportions of 377 patients with severe disease activity observed for 1-month, 2-month, and 3-month time blocks who had a change in DMARD drug or dose were 36%, 57%, and 74%, respectively. Over 12 months, a change in DMARD drug or dose was observed for 44%, 50%, and 68% of 377 patients with severe disease within 3 months, 6 months, and 12 months, respectively, of the patient meeting criteria for severe disease activity. A change in DMARD drug or dose was observed for 21%, 23%, and 34% of 149 patients with moderate disease activity within 3, 6, and 12 months, respectively, of the patient meeting criteria for moderate disease activity.

CONCLUSION

Rates of pharmacologic interventions for patients with moderate and severe RA disease activity vary substantially by intensity and duration of disease activity and by duration of period for observing change. Lack of precision in explicit process criteria could substantially mislead comparisons of quality of care across comparison groups.

Comparison of the electromechanical responsiveness of alpha-1-adrenoceptor stimulation in ventricles of normal and cardiomyopathic hamsters

Alterations in alpha(1)-adrenoceptor (alpha(1)AR) density and related signal transduction proteins were reported in cardiomyopathic hearts in the failing stage. The electromechanical modification of alpha(1)-adrenergic stimulation in the failing heart is unclear. The present study compares the alpha(1)AR-stimulated electromechanical response in failing ventricles of genetically cardiomyopathic BIO 14.6 hamsters (280-320 days old) with that in age-matched normal Syrian hamsters. The action potential was recorded with a conventional microelectrode technique, and twitch force was measured with a transducer. In the presence of propranolol, phenylephrine increased the contraction and prolonged the action potential duration (APD) to similar values in ventricles of both strains, despite a prolonged basal APD in cardiomyopathic ventricles. The positive inotropism stimulated by phenylephrine was inhibited by staurosporine, and was potentiated by 4 beta-phorbol-12,13-dibutyrate (PDBu) in both strains. The maximum positive inotropic effect of phenylephrine in PDBu-treated ventricles of normal hamsters was significantly greater than that in BIO 14.6 hamsters. The effects of phenylephrine on the ventricular force-frequency relationship and on the mechanical restitution in both normal and BIO 14.6 strain hamsters were examined. The uniform negative force-frequency relationship and the altered mechanical restitution reveal a defect of intracellular Ca(2+) handling in cardiomyopathic BIO 14.6 hamsters. alpha(1)-Adrenergic modulation cannot convert the defective properties in the model of the failing heart. Nevertheless, phenylephrine decreased post-rest potentiation in short rest periods, and enhanced post-rest decay after longer resting periods. The results indicate that alpha(1)-adrenergic action enhances a gradual loss of Ca(2+) from the sarcoplasmic reticulum, although its action in prolonging the APD can indirectly increase the influx of Ca(2+).

[Effects of ANSON NANOTECH on the healing of cutaneous chronic wounds]

OBJECTIVE

To observe the effects of ANSON NANOTECH on the healing of cutaneous chronic wounds.

METHODS

Thirty-four cases with 44 wounds were locally treated with ANSON NANOTECH in the wounds after debridement. Among them, there were 15 cases with traumatic ulcer (23 wounds), 9 cases with pressure ulcer(11 wounds), 5 cases with diabetes ulcer, and 5 cases with radiation ulcer. The healing time of wounds was used to evaluate the treatment results.

RESULTS

The healing time in all of chronic wounds were accelerated. All wounds from trauma, diabetes and pressure were healed within 4 weeks and another 2 wounds from radiation injuries were healed over 4 weeks. The healing rate within 4 weeks was 95.5%.

CONCLUSION

The results indicate that ANSON NANOTECH can accelerate the healing of chronic wounds. The mechanism probably include sterilization, improvement of local microcirculation, promotion of cell growth, and so on.

Stress distribution of the foot during mid-stance to push-off in barefoot gait: a 3-D finite element analysis

OBJECTIVE

To quantify stress distribution of the foot during mid-stance to push-off in barefoot gait using 3-D finite element analysis.

DESIGN

To simulate the foot structure and facilitate later consideration of footwear. Finite element model was generated and loading condition simulating barefoot gait during mid-stance to push-off was used to quantify the stress distributions.

BACKGROUND

A computational model can provide overall stress distributions of the foot subject to various loading conditions.

METHODS

A preliminary 3-D finite element foot model was generated based on the computed tomography data of a male subject and the bone and soft tissue structures were modeled. Analysis was performed for loading condition simulating barefoot gait during mid-stance to push-off.

RESULTS

The peak plantar pressure ranged from 374 to 1003 kPa and the peak von Mises stress in the bone ranged from 2.12 to 6.91 MPa at different instants. The plantar pressure patterns were similar to measurement result from previous literature.

CONCLUSIONS

The present study provides a preliminary computational model that is capable of estimating the overall plantar pressure and bone stress distributions. It can also provide quantitative analysis for normal and pathological foot motion.

RELEVANCE

This model can identify areas of increased pressure and correlate the pressure with foot pathology. Potential applications can be found in the study of foot deformities, footwear, surgical interventions. It may assist pre-treatment planning, design of pedorthotic appliances, and predict the treatment effect of foot orthosis.

Evidence for a large-scale remnant of subducted lithosphere beneath Fiji

We combine spatial variations of P- and S-wave speeds, 1000 fault plane solutions, and 6600 well-determined hypocenters to investigate the nature of subducted lithosphere and deep earthquakes beneath the Tonga back-arc. We show that perplexing patterns in seismicity and fault plane solutions can be accounted for by the juxtaposition of a steep-dipping Wadati-Benioff zone and a subhorizontal remnant of slab that is no longer attached to the actively subducting lithosphere. The detached slab may be from a previous episode of subduction along the fossil Vitiaz trench about 5 to 8 million years ago. The juxtaposition of slabs retains a large amount of subducted material in the transition zone of the mantle. Such a configuration, if common in the past, would allow the preservation of a primordial component in the lower mantle.

The underlying diseases and follow-up in Taiwanese children screened by urinalysis

To date, the underlying diseases and follow-up of Taiwanese children screened by urinalysis have not been reported. The grading of urine abnormalities varied from grade A (microscopic hematuria only), grade B (light proteinuria only), grade C (light proteinuria and microscopic hematuria) to grade D (heavy proteinuria). From January 1991 to August 1998, 630 students, aged 6-15 years and with positive urinary screening, were admitted to our hospital for further evaluation. Of these, 573 students had confirmed abnormal findings, 298 were boys, 275 were girls, and 294 students received a renal biopsy and have had regular follow-up visits. This study was designed to retrospectively elucidate: (1) the relationship between grading of urine abnormality and underlying disease; (2) the relationships among hypertension, grading of urine abnormality, and underlying disease; (3) the underlying disease of low serum C3 level; and (4) to determine whether urinary screening progressively decreased the number of students with end-stage renal disease (ESRD) annually. The results show that glomerular nephritis (GN) is still one of the major causes of urinary abnormalities. The most-important secondary GN was systemic lupus erythematosus (SLE) with lupus nephritis. One-quarter of the patients fulfilled at least four of the revised American Rheumatology Association (ARA) criteria for SLE at first administration, while the others who fulfilled only two to three of the revised ARA criteria had gradually developing signs and symptoms of SLE at follow-up. The percentage of SLE patients amongst anti-nuclear antibody (ANA) positive children was 72%. Membranoproliferative GN is very rare. The distribution of hypertension was 8.2% in grade A, 10.7% in grade B, 9.7% in grade C, and 28.9% in grade D urinary abnormality. There were statistical differences between grade D and either grade A or B or C (P<0.05). Lower serum C3 levels were found only in a minority of patients, including those with SLE. In this series, focal segmental glomerular sclerosis (FSGS) and active class IV lupus nephritis patients were found early enough to receive methylprednisolone pulse plus cyclosporine A therapy. To date there have been only 2 cases (5%) of FSGS with impaired renal function, and none of the lupus nephritis patients are in the predialysis stage. In conclusion, GN is still the major cause of urinary screening abnormality. ANA study is indicated in all Chinese students with abnormal urinary screening. The correlations between the severity of proteinuria and hypertension showed more-severe proteinuria in patients with nephritis as well as in those with hypertension.

Immune reponses in human mesangial cells regulated by emodin from Polygonum hypoleucum Ohwi

In the hope of identifying agents of therapeutic value in glomerulonephritis from Chinese herbs, we found that methanolic extracts of Polygonum hypoleucum Ohwi (P. hypoleucum Ohwi) inhibit human mesangial cells proliferation activated with interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) previously. This study was designed to identify bioactive components from P. hypoleucum Ohwi and elucidate their action mechanisms. We tested four anthraquinones emodin, emodin 1-O-beta-D-glucoside (49A), physcion (62A), and physcion 1-O-beta-D-glucoside (50A) purified from P. hypoleucum Ohwi for their effects on human mesangial cell proliferation and cytokines production in vitro. On a percentage basis, emodin had the highest suppressing activity on the human mesangial cells proliferation activated by IL-1beta and IL-6. The IC50 of emodin on human mesangial cells proliferation were 17.9+/-1.2 microM. In contrast to 49A, 50A, and 62A, emodin also decreased IL-1beta, IL-6 and tumor necrosis factor-alpha (TNF-alpha) production in human mesangial cells activated with IL-1beta and IL-6. The IC50 of emodin on IL-1beta, IL-6 and TNF-alpha production in activated human mesangial cells were 16.6+/-1.8 microM, 8.2+/-1.3 microM, and 9.5+/-1.6 microM, respectively. Moreover, IL-1beta and TNF-alpha mRNA expression in activated human mesangial cells was impaired by emodin. The intracellular free Ca2+ concentration ([Ca2+]i) in IL-1beta and IL-6 activated human mesangial cells was decreased by emodin. It is unlikely that cytotoxicity was involved because no cell deaths were observable. We hypothesize that the inhibitory mechanisms of emodin on activated human mesangial cells proliferation may be related to the impairments of gene expression and production of cytokines and [Ca2+]i in the cells.

Cutaneous nerve degeneration induced by acrylamide in mice

Acrylamide is a neurotoxin producing distal axonopathy. Previous studies mainly focused on large-diameter motor and sensory nerves, and the influences of acrylamide neurotoxicity on small-diameter sensory nerves in the skin remained elusive. We investigated skin innervation in mice intoxicated by acrylamide. Small-diameter sensory nerves in the skin degenerated after acrylamide intoxication. Epidermal nerve swelling was the earliest sign of acrylamide intoxication, with 29.5+/-2.4% of swollen epidermal nerves in the initial stage (P<0.001). There was a trend of progressive loss of epidermal nerves with a significantly reduced epidermal nerve density in the late stage (P<0.003). In the mean time, degenerating dermal nerves exhibited a beaded appearance. These results suggest the scenario of small-diameter cutaneous nerve degeneration in acrylamide neurotoxicity: beginning with epidermal nerve terminal swelling in the initial stage and resultant epidermal nerve depletion in the late phase.

Taxol reduces cytosolic E-cadherin and beta-catenin levels in nasopharyngeal carcinoma cell line TW-039: cross-talk between the microtubule- and actin-based cytoskeletons

Taxol affects microtubule dynamics by promoting microtubule assembly. To obtain a better insight into possible cross-talk between the microtubule- and actin-based cytoskeletons, we studied the short-term effects of Taxol treatment on the expression of actin and the E-cadherin/catenin complex in the nasopharyngeal carcinoma cell line TW-039 using immunofluorescence, immunoprecipitation, and immunoblotting methods. Morphologic changes in actin filaments, including ventral actin clumps and perijunctional actin blebs, were seen at Taxol concentrations > or =1 microM. Levels of detergent-soluble E-cadherin fell to 53% or 58% compared to controls in cells treated, respectively, with 1 or 5 microM Taxol, while levels of detergent-soluble beta-catenin fell to 76% or 74%. Levels of the detergent-soluble pool of alpha- and gamma-catenin and the detergent-insoluble pool of the E-cadherin/catenin complex were unchanged by Taxol treatment and no significant difference was seen in the levels of adenomatous polyposis coli or glycogen synthase-3beta or tyrosine phosphorylation patterns. These results suggest that modulation of microtubule dynamics by Taxol may have effects on the expression of actin and the cytosolic E-cadherin and beta-catenin in nasopharyngeal carcinoma cells through pathways not involving the phosphorylation of beta-catenin.

High-frequency interconversion of turbid and clear plaque strains of bacteriophage f1 and associated host cell death

Under normal cultivation conditions, a mixture of turbid and clear plaques is often apparent in cultures of bacterial cells infected with filamentous bacteriophages. Beginning with a culture of wild-type filamentous phage f1, which itself produces turbid plaques, a clear plaque strain (c1) was isolated. From c1, the turbid plaque strain t1 was isolated; from t1, the clear plaque strain c2 was isolated; and from c2, the turbid plaque strain t2 was isolated. Each of these strains was generated with a frequency of approximately 1 x 10(-4). Although filamentous phages have been thought not to induce host cell death, both turbid and clear plaque strains of f1 killed host bacteria. Plating of bacterial cells 1 h after infection revealed that colonies produced by cells infected with either wild-type f1 or strain c2 were smaller than those derived from uninfected cells, and that colony formation by infected cells was reduced by 15% and 38%, respectively. The time course of bacterial growth revealed that, at 4 h after infection, the number of CFU per milliliter of culture of cells infected with wild-type f1 or with strain c2 was reduced by 27% and 95%, respectively, compared with that for uninfected cells. Microculture analysis also revealed that the percentages of nondividing cells in f1 or c2 infected were 19% and 52%, respectively, 4 h after infection with wild-type f1 or with strain c2; no such cells were detected in cultures of uninfected cells. Negative staining and electron microscopy showed that 20% and 61% of cells infected with wild-type f1 or with strain c2 were dead 4 h postinfection. Finally, although the rates of DNA synthesis were similar for infected and uninfected cells, the rates of RNA and protein synthesis were markedly reduced in infected cells.

Persistent transforming growth factor-beta 1 expression may predict peritoneal fibrosis in CAPD patients with frequent peritonitis occurrence

The efficiency of continuous ambulatory peritoneal dialysis depends on the permeability of the peritoneal membrane. Peritoneal fibrosis (PF) causes loss of the dialytic function. Several studies have indicated that PF is closely related to the proliferation of peritoneal fibroblasts and the deposition of extracellular matrix. Transforming growth factor-beta 1 (TGF-beta1) plays a major role in stimulating extracellular matrix deposition. Frequent peritonitis occurrence may cause persistent TGF-beta1 mRNA expression. In an attempt to search for a factor related to PF, we designed a longitudinal study to measure TGF-beta1 levels in dialysate and TGF-beta1 mRNA expression in peritoneal mononuclear cells from peritoneal dialysate before onset, once a week during peritonitis, and after peritonitis in high and low peritonitis occurrence (HPO and LPO) patients. Fifteen patients with a LPO rate and 5 patients with a HPO rate were followed up longitudinally. Meanwhile, TGF-beta1 levels and TGF-beta1 mRNA expression were augmented in peritoneal dialysate effluents before, during, and after the episodes of peritonitis. The peritoneal permeability was evaluated by the peritoneal equilibration test. The results revealed that in the LPO group, TGF-beta1 and TGF-beta1 mRNA were detectable at early stages of peritonitis, but the levels decreased rapidly and were undetectable 2 weeks after peritonitis. On the other hand, in the HPO group, TGF-beta1 and TGF-beta1 mRNA persisted for a long time. We could detect TGF-beta1 and TGF-beta1 mRNA in dialysate effluents and peritoneal mononuclear cells even 2, 3, and 4 weeks after episodes of peritonitis. When compared with that of first or second episode of peritonitis, the peritoneal function evaluated with the peritoneal equilibration test was found to obviously deteriorate during the third episode of peritonitis. These findings were confirmed by an in situ hybridization technique to evaluate the relationship between TGF-beta1 mRNA expression and PF from biopsied peritoneal specimens. These findings suggest that the high TGF-beta1 levels in the dialysate are related to an increased expression of TGF-beta1 in the peritoneum. Thus, the persistent TGF-beta1 expression in the peritoneum may serve as a useful parameter in predicting PF in continuous ambulatory peritoneal dialysis patients with frequent peritonitis occurrence.

The chi-Chi earthquake sequence: active, out-of-sequence thrust faulting in taiwan

We combined precise focal depths and fault plane solutions of more than 40 events from the 20 September 1999 Chi-Chi earthquake sequence with a synthesis of subsurface geology to show that the dominant structure for generating earthquakes in central Taiwan is a moderately dipping (20 degrees to 30 degrees ) thrust fault away from the deformation front. A second, subparallel seismic zone lies about 15 kilometers below the main thrust. These seismic zones differ from previous models, indicating that both the basal decollement and relic normal faults are aseismic.

E-, P-, and N-cadherin are co-expressed in the nasopharyngeal carcinoma cell line TW-039

The cadherin/catenin complex plays a key role in the initiation of cell-cell recognition, and adhesion, and the elaboration of structural and functional organization in multicellular tissues and organs. It is associated with tumor metastasis and also acts as an "invasion suppressor" of cancer cells. Nasopharyngeal carcinoma (NPC) is notorious for its highly metastatic nature. The expression of the E-cadherin/catenin complex is down-regulated in NPC tumor specimens. To obtain better insight into the intercellular adhesive property of NPC cells, we used immunofluorescence microscopy, immunoprecipitation, and immunoblot analysis to examine the expression of the classical cadherins and beta-catenin in a NPC cell line, TW-039. The results demonstrate a change in the distribution of E-cadherin from cytosolic flakes to cell-cell contacts with increasing time in culture. Between days 1 and 5 after plating, the detergent-insoluble fraction of E-cadherin increased from 20% to 37% of total E-cadherin, and that for P-cadherin increased from 33% to 40%. By contrast, the values for beta-catenin remained unchanged (26% and 25%). Both immunofluorescence and immunoblot studies suggested that P-cadherin may be involved in pioneer contact adhesion of TW-039 cells. Interestingly, E-, P-, and N-cadherin are co-expressed in this cell line. Immunoprecipitation studies also showed that other members of the cadherin family may be involved in the contact adhesion of TW-039 cells.

Ionic mechanisms for the antiarrhythmic action of cinnamophilin in rat heart

We investigated the electrophysiological effect and antiarrhythmic potential of cinnamophilin (Cinn), a thromboxane A(2) antagonist isolated from Cinnamomum philippinense, on rat cardiac tissues. Action potential and ionic currents in single rat ventricular cells were examined by current clamp or voltage clamp in a whole-cell configuration. In 9 episodes of ischemia-reperfusion arrhythmia, 10 microM Cinn converted 6 of them to normal sinus rhythm. Cinn suppressed the maximal rate of rise of the action potential upstroke (V(max)) and prolonged the action potential duration at 50% repolarization (APD(50)). Voltage clamp study showed that the suppression of V(max) by Cinn was associated with an inhibition of sodium inward current (I(Na), IC(50) = 10.0 +/- 0.4 microM). At 30 microM, V(1/2) for the steady-state inactivation curve of I(Na) was shifted from -84.1 +/- 0.2 to -93.0 +/- 0.5 mV. Cinn also reduced calcium inward current (I(Ca)) dose-dependently with an IC(50) value of 9.5 +/- 0.3 microM. Cinn (10 microM) reduced the I(Ca) with a negative shift of V(1/2) for the steady-state inactivation curve of I(Ca) from -32.2 +/- 0.3 to -50.7 +/- 0.4 mV. The prolongation of APD(50) was associated with an inhibition of the integral of potassium outward current with IC(50) values between 4.8 and 7.1 microM. At 10 microM, Cinn reduced I(Na) without a negative shift of its voltage-dependent steady-state inactivation curves. The inhibition of transient outward current (I(to)) by Cinn (3-30 microM) was associated with an acceleration of its time constant of inactivation and negative shift of its potential-dependent steady-state inactivation curves. The equilibrium dissociation constant (K(d)) of Cinn to inhibit open state I(to) channels, as calculated from the time constant of developing block, was 18.3 microM. The time constant of recovery of I(to) from inactivation state was unaffected by Cinn. The rate constant for the relief from the depolarization-dependent block of I(to) was calculated to be 23. 9 ms. As compared with its effect on I(to), Cinn exerted about half the potency to block I(Na) and I(Ca). These results indicate that the inhibition of I(Na), I(Ca) and I(to) may contribute to the antiarrhythmic activity of Cinn against ischemia-reperfusion arrhythmia.

Intrarenal infusion of supernatant from cytokine-activated human mesangial cells may cause glomerular damage

BACKGROUND

The pathogenesis of glomerular damage in glomerulonephritis (GN) is not fully understood. Several studies have suggested that reactive oxygen molecules play a role in renal disease. It is known that, during GN, mesangial cells are activated. In a previous study, we demonstrated that in vitro interleukin (IL)-1 plus IL-6 stimulated cultured human mesangial cell (HMC) activation to release free oxygen radicals.

METHODS

In this study, we measured hydrogen peroxide (H2O2) and superoxide anion (O2-) levels after stimulation by IL-1 plus IL-6 in cultured HMCs. We then infused H2O2 directly into the left renal arteries of Sprague-Dawley rats. We also infused the culture supernatants of HMCs after stimulation by IL-1 plus IL-6 into the left renal arteries of rats. Two hours after stopping the infusion, the kidneys were removed and fixed using Carson's modified Millonig's buffer for electron microscopy.

RESULTS

Both 100 microM H2O2 and supernatants of HMCs stimulated by IL-1 10 U/ml plus IL-6 1,000 U/ml caused similar glomerular damage, including blebbing and sloughing of endothelial cells, and denuded basement membrane in glomeruli. When 100 microM H2O2 or supernatants of cytokine-activated HMCs were infused into renal arteries, they caused hematuria and proteinuria.

CONCLUSIONS

These results suggest that activated HMCs may secrete free radicals and cause glomerular damage.

The value of Ga-67 renal SPECT in diagnosing and monitoring complete and incomplete treatment in children with acute pyelonephritis

PURPOSE

This study evaluated the utility of Ga-67 renal SPECT for diagnosing acute pyelonephritis (APN) in children and monitoring them.

METHODS

Seventy-one children (ages 1 week to 12 years) who were thought clinically to have APN were included in the study. The disease was considered present if the patients had all of the following: fever (38.5 degrees C), pyuria (leukocyte counts/per high-power field > or = 10), and a positive result of a urinary culture or blood culture. Tc-99m DMSA, Ga-67 renal SPECT, and voiding cystourethrography were performed, with informed consent from the patients' parents, within 3 days after hospitalization. Three months after treatment, Tc-99m DMSA and Ga-67 renal SPECT were repeated in those patients who had abnormal results of the initial Ga-67 renal SPECT.

RESULTS

In the diagnostic study, Ga-67 renal SPECT was superior to DMSA renal SPECT in detecting lesions (97% vs. 79%). Three children had false-negative results with Ga-67 renal SPECT. Seventeen kidneys were negative with Tc-99m DMSA but positive with Ga-67 renal SPECT. No patients had any Ga-67 uptake on post-therapy imaging. However, 32 of 107 kidneys (30%) had permanent renal scars. In these 107 kidneys, 78 (73%) were associated with high-grade vesicoureteral reflux (VUR; VUR grade > or = 3) and 29 (27%) with low-grade or no VUR.

CONCLUSIONS

High-grade VUR tends to be associated more with APN than has been reported by others, probably because of an underestimation of APN by ultrasonography or DMSA. Ga-67 renal SPECT is sensitive and useful not only in diagnosis but also for monitoring and follow-up of children with clinical suspicion of APN, especially in those with equivocal results after DMSA renal SPECT studies.

Age-dependent acrylamide neurotoxicity in mice: morphology, physiology, and function

Acrylamide intoxication produces peripheral neuropathy characterized by weakness and ataxia in both humans and experimental animals. Previous studies on animals of different ages and species indicate that the longest and largest nerves are affected earlier with the major pathology in the terminal parts of axons, i.e., distal axonopathy. However, several issues have remained elusive; for example, what are the earliest pathological changes? An equally intriguing question is whether younger animals are more susceptible to acrylamide than older animals. To address these issues, we compared the vulnerability to acrylamide of 3- and 8-week-old mice. These mice were intoxicated with acrylamide in drinking water (400 ppm). The sequence of intoxication could be categorized into three stages. In the initial stage, there was no visible weakness or ataxia. The only noticeable changes were poor performance on the rota-rod test and swelling of motor nerve terminals. Obvious weakness and ataxia of hindlimbs developed gradually (here designated as the early stage). The weakness and ataxia progressed at variable speeds in mice of different ages, and eventually the forelimbs (quadriparesis) were affected in the late stage. Each stage appeared earlier in 3-week-old mice than in 8-week-old mice (7.1 +/- 1.1 vs 15.6 +/- 4.0 days, P < 0.01 for the early stage; and 15.3 +/- 2.1 vs 31.7 +/- 6.0 days, P < 0.01 for the late stage). The progression of neurological deficits was also faster in the younger mice (7.2 +/- 1.8 vs 16.3 +/- 4.2 days, P < 0.01). Pathological changes in the distal parts of motor nerves innervating hindfoot muscles were evaluated by combined cholinesterase histochemistry and immunocytochemistry for neuronal markers to demonstrate motor nerve terminals and neuromuscular junctions simultaneously. In the initial stage, there was axonal swelling in motor nerve terminals. As acrylamide intoxication continued, axonal swelling extended into junctional folds and into the intramuscular nerves, which resulted in Wallerian-like degeneration. Our results indicate that younger mice show a much higher susceptibility to acrylamide intoxication, and pathological changes precede neurological symptoms.

Blocking of cell proliferation, cytokines production and genes expression following administration of Chinese herbs in the human mesangial cells

In the hope of identifying agents of therapeutic value in immuoglobulin A nephropathy (IgA-N), we tested crude methanol extracts of 15 Chinese herbs for their effect on human mesangial cell proliferation. The results indicated that 4 out of the 15 crude extracts inhibited human cells proliferation activated by IL-1beta and IL-6. The extracts and their median inhibitory concentrations were as follows (in microg/ml): Ludwiga octovalvis (MLS-052), 49.9 +/- 1.8; Rhus semialata (MLS-053), 31.2 +/- 1.6; Tabernaemontana divaricata (MLS-054), 50.0 +/- 2.1; Amepelopsis brevipedunculata (MLS-059), 42.9 +/- 1.1. These findings indicate that human mesangial cells were most sensitive to MLS-053 treatment. These herbs also decreased interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) production. Moreover, IL- 1beta mRNA expression was inhibited by Rhus semialata (R. semialata; MLS-053). It is unlikely that cytotoxicity was involved, because no cell deaths were observable. We hypothesize that the inhibitory mechanisms of these Chinese herbs may be related to the impairments of gene expression and production of cytokines in human mesangial cells. Plans are underway for the isolation of pure compounds from these Chinese herbs and the elucidation of their mechanisms of action.

Delayed irradiation effects on nasal epithelium in patients with nasopharyngeal carcinoma. An ultrastructural study

The ostiomeatal complex is responsible for the clearance of most sinus secretions. To evaluate the delayed effects of irradiation. this study examined the infundibulum mucosa of 10 patients who developed sinusitis after receiving radiotherapy for nasopharyngeal carcinoma (NPC). Pathologic findings under the light microscope revealed an increased deposition of dense collagenous fibers in the lamina propria. The epithelial cells also transformed into a stratified arrangement and showed gradual reduction of cytoplasmic volume. Ultrastructural observations detected areas of ciliary loss, intercellular and intracellular vacuolation, and ciliary dysmorphism. Most of these pathologic findings were observed even in a patient 23 years after irradiation. The results presented herein suggest that radiotherapy may cause long-term damage to the nasal epithelium that may be responsible for the prolonged sinusitis of irradiated NPC patients.

Trophic interactions between sensory nerves and their targets

Neurotrophins are target-derived trophic factors essential for the survival and maintenance of neurons. Among these, nerve growth factor (NGF) and neurotrophin-3 (NT-3) are particularly important for sensory neurons. The actions of neurotrophins are through the p75 low-affinity receptor and the high-affinity receptor tyrosine kinase (trk). Each neurotrophin has its preferred receptor, i.e. trkA for NGF, and trkC for NT-3. The primary sensory neurons in the dorsal root ganglion are classified into two categories, namely, the large and small sensory neurons based on their size. The large sensory neurons with the expression of trkC depend on NT-3 for development and subserve the function of position sensations. Some of the small sensory neurons express trkA and are NGF-dependent. They are responsible for nociceptive sensation, the detection of painful and thermal stimuli. A more intriguing observation is the bidirectional interactions between nociceptive nerves and their target, the skin. The peripheral processes of small sensory neurons innervate the epidermis of the skin as 'free nerve endings'. In denervated skin, there is a drastic reduction in the epidermal thickness, a finding corroborated by the phenomenon of trophic change, the shining and thinning of the skin, in the disorders of peripheral nerves. The performance of animals with peripheral nerve disorders improved after administration of neurotrophic factors. Based on these results, the therapeutic potentials of neurotrophic factors in human are under investigation.

Dynamic helical CT as a novel technique for diagnosing hepatic perfusion disorders

BACKGROUND/AIMS

Perfusion disorders of the liver have seldom been studied by computed tomography (CT). Recent new-generation helical CT by speeding up the scanning time proves it is possible to evaluate these disorders. The purpose of this study is to demonstrate the various patterns of hemodynamic change of the liver in both normal and diseased status by dynamic helical CT technique.

METHODOLOGY

In a period of 1 year, about 1,000 patients received dynamic helical CT examination of the liver due to either clinical suspicion of liver lesions or liver lesions of unknown nature. The examination was performed with a Picker PQ 2000 CT scanner. In total, 100 cc of iodinated contrast agent was injected at a rate of 3.5 cc per second. Two sets of images were acquired at 22 seconds and 75 seconds after the initiation of the contrast injection. Different patterns of hemodynamic change were found and the etiologies and mechanisms were investigated.

RESULTS

Sixty-two cases were found to have perfusion disorder of the liver. Thirty cases were associated with tumors such as hepatoma (17), hemangioma (4) and hepatic metastasis (3). The other 32 cases were non-tumor associated. The perfusion disorders appeared due to liver cirrhosis, anatomic variant, iatrogenic injury, liver abscess, etc. The mechanisms for these perfusion disorders were classified as portal vein compression or thrombosis, arterioportal shunting, hepatic artery encasement, local hyperremic change, aberrant blood supply, steal effect, hepatic venous outflow obstruction, etc. These disorders presented as subcapsular, focal nodular, wedge-shaped, segmental, lobar, or even diffuse in shape and distribution.

CONCLUSIONS

Dynamic helical CT opens a new window for demonstrating and understanding various hepatic perfusion disorders which reflect the hemodynamic change of the liver in both normal and diseased conditions.

Inhibition of activated human mesangial cell proliferation by the natural product of Cordyceps sinensis (H1-A): an implication for treatment of IgA mesangial nephropathy

Cordyceps sinensis (CS) is a parasitic fungus that has been used as a Chinese medicine for a long time in the treatment of nephritis. Today, the hypothesis about the pathogenesis of immunoglobulin A nephropathy (IgAN) is that nephritogenic IgA immune complexes (IgAIC) go to the kidney to stimulate resting mesangial cells to release cytokines and growth factors. These cytokines and growth factors cause mesangial cell proliferation and release matrix, chemical mediators that lead to the glomerular injury. However, nephritogenic IgAIC in humans is still unknown. To solve this problem previously, we established an in vitro model that showed that cultured human mesangial cells (HMC) stimulated with interleukin-1 (IL-1) plus IL-6 can cause mesangial cell proliferation, increasing production of chemical mediators and superoxide anion. An in vivo model also proved that this culture medium may lead to renal injury with hematuria and proteinuria. Therefore, to fractionate the crude components that can be used in the treatment of patients with IgAN, we cultured HMC, and then an HMC activating model with HMC incubated with IL-1 and IL-6 was established. We fractionated the crude methanolic extracts from fruiting bodies of CS with the use of this in vitro inhibition of HMC activation model as our assay method. In brief, the fruiting bodies were extracted by silica gel column chromatography. One out of 6 column fractions, F-2, significantly inhibited the HMC activation by IL-1 plus IL-6. The acute toxicity test with male Institute of Cancer Research mice showed no liver toxicity or mutagenicity. Then we established an IgAN animal model with R36A (Pneumococcal C-polysaccharide purified from Streptococcus pneumoniae) as antigen and anti-R36A IgA monoclonal antibody to form nephritogenic IgA-IC, which can induce hematuria and proteinuria in mice with IgA deposition in the mesangial area. The mice in the IgAN model fed with 1% F-2 in diet had significant reduction of hematuria and proteinuria together with histopathologic improvement. Therefore this fraction was then purified by silica gel column chromatography and high-performance liquid chromatography, which got a purified compound H1-A, which can suppress the activated HMC and alleviate IgAN (Berger's disease) with clinical and histologic improvement. These results give us a new regimen for the treatment of patients with IgAN in the future.

Identification of new renal scarring in repeated episodes of acute pyelonephritis using Tc-99m DMSA renal SPECT

PURPOSE

This prospective study compared the value of Tc-99m DMSA renal planar scintigraphy with SPECT to detect new renal involvement in patients with repeated episodes of acute pyelonephritis (APN).

MATERIALS AND METHODS

Children with suspected APN were transferred to our department for DMSA renal scans. Seventy-two children (ages 1 week to 15 years) had DMSA planar and SPECT imaging performed twice because of clinical or laboratory suspicion of repeated APN. In addition, radiographic voiding cystourethrography was also performed in all cases. The presence of vesicoureteral reflux (VUR) was graded on a scale of 0 to 5.

RESULTS

New lesions were observed with SPECT in 56 kidneys and with planar scintigraphy in 38 kidneys. No patients had a negative result of Tc-99m DMSA renal SPECT who also had a positive Tc-99m DMSA planar result. The degree of VUR as related to APN was diagnosed better with SPECT than with planar scintigraphy (46 compared with 30 and 10 compared with 8, respectively). There is a significant difference (P < 0.05) between the diagnostic ability of these two methods to identify the increased tendency of repeated APN to occur with high-grade VUR compared with low-grade or no VUR.

CONCLUSIONS

High-grade VUR is more commonly associated with renal injury than is low-grade or no VUR. If only Tc-99m DMSA renal planar scintigraphy is performed, renal scarring may be underestimated. Our results suggest that Tc-99m DMSA renal SPECT, rather than planar scintigraphy, should be used routinely in children with a clinical suspicion of APN, especially for those with scarred kidneys and high-grade VUR.

Regional difference in epidermal thinning after skin denervation

Denervation of skin has a profound influence on epidermis; epidermal thinning was a consistent finding in rats. However, it is not clear whether the degree of epidermal thinning was similar in the region receiving the same innervation. In mice, how early epidermal nerves were degenerated after nerve injury remained unknown. To address these issues, we transected the sciatic nerve in mice and compared the changes of epidermal thickness in different areas of the hind foot skin. Epidermal nerves degenerated within 48 h after nerve transection, similar to what was observed in rats. Seven days after nerve transection, there was differential thinning of epidermis. The interpad area, in the center of the sciatic nerve-innervated region, exhibited the most profound degree of epidermal thinning (34.6 +/- 3.1 vs 47.8 +/- 2.4 microns, P < 0.01). The heel area, in the periphery of the sciatic nerve-innervated zone, did not show significant thinning of epidermis after denervation (37.3 +/- 4.8 vs 41.5 +/- 5.1 microns, P > 0.05). The degree of epidermal thinning after denervation in the pad area was the intermediate one: with 98.8 +/- 4.8 vs 120.1 +/- 7.3 microns, P < 0.02, in the rete pegs, and 51.1 +/- 4.1 vs 62.1 +/- 6.0 microns, P < 0.02, in the dermal papilla. The differential thinning was obvious when the thickness of the denervated epidermis was normalized to that of the control epidermis with the ratios of 0.73 +/- 0.03 in the interpad area, 0.83 +/- 0.04 in the rete peg, 0.85 +/- 0.05 in the dermal papilla, and 0.92 +/- 0.05 in the heel. Epidermal thinning was reversed by reinnervation of the epidermis after sciatic nerve crush (41.5 +/- 1.5 vs 45.0 +/- 2.0 microns in the interpad area, P > 0.05). These findings suggest that sensory nerves exhibit trophic influences on the epidermis presumably through the effects of diffusible factors.

Formalin treatment of refractory hemorrhagic cystitis in systemic lupus erythematosus

Hemorrhagic cystitis is a potentially life-threatening complication in systemic lupus erythematosus (SLE). No safe, effective and conservative treatment exists for patients who fail to respond to standard therapy. We report a 17-year-old girl with SLE who suffered from severe hemorrhagic cystitis. Initially, she received frequent red blood cell and platelet transfusions, continuous bladder irrigation, and blood clots were evacuated. Numerous kinds of treatment were tried, including electrocoagulation of bleeding foci, prostaglandin E1 bladder instillation, and hyperbaric oxygen. However, she remained severely anemic and thrombocytopenic necessitating daily transfusions of blood products. After intravesical formalin instillation was performed twice, the hematuria ceased completely.

IgG subclass/IgM ratio and response to therapy in focal segmental glomerulonecrosis

Focal segmental glomerulosclerosis (FSGS) is relatively steroid resistant and no clinical or histological marker can predict the response to therapy. To investigate the role of serum immunoglobulin subclass/IgM in predicting the response to therapy in FSGS, serum concentrations of total IgG, IgG subclasses, and the ratio of serum IgG subclasses to total IgG (% IgG subclass) were measured in 27 children during the acute nephrotic state. Prednisolone, cyclophosphamide, and Persantine (dipyridamole) were given for 12 weeks. We divided the patients into good responders or poor responders according to clinical response. The clinical and nephrotic status were similar in both groups. Fourteen patients were good responders with higher serum IgGI/IgM than that of non-responders (4.00+/-0.67 vs. 1.61+/-0.20, P<0.05). There was no significant difference in IgG2/IgM between these two groups. These results suggest that higher serum IgGI/IgM ratios may be associated with a better clinical response. These changes may reflect dysregulation of immunoglobulin class switching in patients with FSGS.

Clinical aspects of the hemolytic uremic syndrome

Hemolytic uremic syndrome (HUS) can be clinically classified into two types: typical cases with a diarrheal prodrome of association with E. coli O157, and atypical cases without antecedent diarrhea. However, HUS is not common in Taiwan. To evaluate the clinical course, complications and outcome of HUS in children, and to identify the risk factors for mortality, retrospectively, seven cases of HUS in our hospital in the past 6 years were studied. Six of them were boys, and one was a girl. Their ages ranged from 0.67 to 3 years. None of them were preceded by diarrheal prodrome. Acute renal failure, hypertension and liver involvement were noted in all cases. Stroke and seizure developed in three of the cases with sequelae. Two cases progressed into end-stage renal disease (ESRD). One case developed acute respiratory distress syndrome (ARDS). Two cases (28.5%) expired. ESRD especially associated with ARDS was highly related to mortality.

Chinese herbs as modulators of human mesangial cell proliferation: preliminary studies

In the hope of identifying agents of therapeutic value in immunoglobulin A nephropathy (IgA-N), we tested crude methanol extracts of 15 Chinese herbs for their effect on human mesangial cel proliferation in vitro. The results indicated that 7 out of the 15 crude extracts inhibited human mesangial cell proliferation activated by interleukin-1beta and interleukin-6. The extracts and their median inhibitory concentrations were as follows (in microg/ml): Selaginella tamariscina (MLS-032), 56.0 +/- 2.0; Ixeris chinensis (MLS-033), 62.7 +/- 1.7; Polygonum hypoleucum Ohwi (MLS-034), 25.0 +/- 1.5; Scutellaris rivularis (MLS-036), 39.6 +/- 1.1; Condonacanthus paucifiorus (MLS-042),63.6 +/- 2.6; Xanthium strumarium (MLS-043), 42.8 +/- 1.3; Daemonoropus margaritae (MLS-044), 56.1 +/- 1.9. These findings indicate that human mesangial cells were most sensitive to MLS-034 treatment. These herbs also decreased interleukin-1beta and tumor necrosis factor-alpha production. Moreover, TNF-alpha mRNA expression was inhibited by MLS-034. It is unlikely that cytotoxicity was involved, because no cell deaths were observable. We hypothesize that the inhibitory mechanisms of these Chinese herbs may be related to the impairments of gene expression and production of cytokines in human mesangial cells. Plans are underway for the isolation of pure compounds from these Chinese herbs and the elucidation of their mechanisms of action.

Clinical efficacy of cyclosporin a neoral in the treatment of paediatric lupus nephritis with heavy proteinuria

Cyclosporin A (CsA) was introduced in recent years for the treatment of lupus nephritis in patients with steroid resistance or in those with severe corticosteroid toxicity. Our previous study on paediatric patients showed that Neoral (a new microemulsion formulation) had better bioavailability than CsA capsules. To evaluate the clinical efficacy of Neoral in children with lupus nephritis compared with conventional therapy, we performed an open randomized study on 40 children, ranging from 9 to 14 yr old, with class III-V lupus nephritis and heavy proteinuria. They were randomly assigned to either Neoral (5 mg/kg/day), administered q.12.h, or prednisolone (2 mg/kg/day) plus cyclophosphamide (2 mg/kg/day) for 1 yr. Both groups showed a significant decrease in proteinuria (Neoral: 4.62 +/- 1.93 to 0.35 +/- 0.29 g/day, P < 0.05; prednisolone plus cyclophosphamide: 4.52 +/- 1.86 to 0.62 +/- 0.21 g/day, P < 0.01). The CH50 haemolytic assay titre decreased after 1 yr of Neoral treatment (26.5 +/- 0.9 to 21.4 +/- 2.2 U/ml, P < 0.05). Serum C3 and anti-double-stranded (ds) DNA antibody levels also fell with Neoral (C3: 86.2 +/- 6.8 to 76.3 +/- 4.5 mg/dl; anti-ds DNA antibodies: 14.1 +/- 3.2 to 8.2 +/- 1.4 IU/ml, P < 0.05). The Neoral group had a significant increase in growth rate over the prednisolone plus cyclophosphamide group (8.2 +/- 1.1 cm/yr vs 2.7 +/- 0.6 cm/yr, P < 0.01) with improvement of growth status. During the study period, patients tolerated Neoral well with no significant changes in renal function, liver function or lipid profile. Our study implies that Neoral appears to be effective in suppressing proteinuria. Neoral should be regarded as being adjunctive therapy, perhaps with a steroid-sparing effect, in paediatric lupus nephritis. However, its long-term use awaits further studies.

Persistent transforming growth factor beta 1 expression may predict peritoneal fibrosis in CAPD patients with frequent peritonitis occurrence

The efficiency of continuous ambulatory peritoneal dialysis (CAPD) depends on the permeability of the peritoneal membrane. Peritoneal fibrosis (PF) causes the loss of dialytic function. Several studies have indicated that PF is closely related to the proliferation of peritoneal fibroblasts and the deposition of extracellular matrix (ECM). Transforming growth factor beta 1 (TGF beta 1) plays a major role in stimulating ECM deposition. Frequent peritonitis occurrence may cause persistent TGF beta 1 mRNA expression. In an attempt to search for a factor related to PF, we designed a longitudinal study to measure TGF beta 1 levels in dialysate and TGF beta 1 mRNA expression in peritoneal mononuclear cells (PMNCs) from peritoneal dialysate before, at the onset of and once a week during peritonitis and after peritonitis in patients with high peritonitis occurrence (HPO) and patients with low peritonitis occurrence (LPO). Fifteen patients with a LPO rate and 5 patients with a HPO rate were followed up longitudinally. Meanwhile, TGF beta 1 levels and TGF beta 1 mRNA expression were augmented in peritoneal dialytic fluid before, during, and after the episodes of peritonitis. Peritoneal permeability was evaluated by the peritoneal equilibration test (PET). The results revealed that in the LPO group, TGF beta 1 and TGF beta 1 mRNA were detectable at early stages of peritonitis, but the levels decreased rapidly and were undetectable 2 weeks after peritonitis. On the other hand, in the HPO group, TGF beta 1 and TGF beta 1 mRNA persisted for a long time. We could detect TGF beta 1 and TGF beta 1 mRNA in dialytic fluid and PMNCs even 2, 3, and 4 weeks after episodes of peritonitis. When compared with that of the first or second episode of peritonitis, peritoneal function evaluated with the PET was found to obviously deteriorate at the third episode of peritonitis. These findings were confirmed by an in situ hybridization technique to evaluate the relationship between TGF beta 1 mRNA expression and PF from biopsied peritoneal specimens. These findings suggest that the high TGF beta 1 levels in the dialysate are related to an increased expression of TGF beta 1 in the peritoneum. Persistent TGF beta 1 expression in the peritoneum may serve as a useful parameter in predicting PF in CAPD patients with frequent peritonitis occurrence.

Ultrastructural localization and regulation of protein gene product 9.5

Protein gene product 9.5 (PGP), a ubiquitin hydrolase, is abundant in the nervous system. To investigate the ultrastructural localization of PGP and the regulation of its expression, we performed electron microscopic immunocytochemistry and reverse transcription-polymerase chain reaction (RT-PCR) on normal and transected rat sciatic nerves. In normal nerves, strong PGP-immunoreactivity was localized in the myelinated and unmyelinated axons with virtually no staining in the Schwann cells. After nerve degeneration, denervated Schwann cells exhibited intense staining for PGP, corroborated with up-regulation of PGP transcripts by RT-PCR. The present data suggest that the pattern of expression of PGP is more complicated than was expected previously, and reflects the integrity of nerves and status of axon-Schwann cell interactions.

Cyclosporin pharmacokinetics following administration of capsules and Neoral in paediatric patients with lupus nephritis

AIMS

Neoral is a new microemulsion form of cyclosporin. Pharmacokinetic reports in children are scarce. Therefore, we performed a pharmacokinetic study between Cyclosporin A (CsA) capsules and Neoral in paediatric patients with lupus nephritis.

METHODS

A single 5 mg kg(-1) dose orally of either CsA capsules or Neoral was given to 10 paediatric patients (serum creatinine < 1.5 mg dl(-1)). CsA whole blood levels were measured for 24 h post-dose by h.p.l.c.

RESULTS

Neoral had a higher C(max) and AUC(C(max): 943 +/- 176 ng ml(-1); AUC: 4612 +/- 785 ng ml(-1) h) than those of the CsA capsules (C(max): 697 +/- 187 ng ml(-1); AUC: 3483 +/- 873 ng ml(-1) h; P < 0.05). There was no difference in t(max) and t(1/2,z) between the two groups.

CONCLUSIONS

CsA Neoral had improved absorption and bioavailability, which is similar to what is reported in adults. However, interpatient variability still existed. Careful drug monitoring and dose adjustment should be performed during treatment to avoid nephrotoxicity, especially in lupus nephritis.

Protection of ebselen against anoxic damage of cultured neurons of cerebral cortex

AIM

To study the protective effect of ebselen on anoxic damage of brain cells.

METHODS

On d 10 after plating of the cortical neurons from 1-d-old rat, cultures were placed under 95% N2 + 5% CO2 for 2-6 h. Lactate dehydrogenase (LDH) in supernatant, thiobarbituric acid reactive substance (TBARS) and glutathione peroxidase (GSH-Px) activity of neurons were determined.

RESULTS

Under anoxia, efflux of LDH and TBARS from cultured neurons increased while GSH-Px activity decreased. Ebselen reduced the efflux of LDH and TBARS in a dose-related manner and increased the total GSH-Px activity.

CONCLUSION

Ebselen can protect neurons from anoxic damage.

[Protection of ebselen on oxygen free radical-induced lipid peroxidation damage of cultured rat cortical neuron and cortical mitochondria]

Ebselen (2-phenyl-1, 2-benzisoselenanzol-3 (2H) one, C13 H9NOSe) is a seleno-organic anti-oxidant compound. In this study, the effect of ebselen on lipid peroxidation damage induced by O2.- and .OH in vitro, of cultured rat cortical neuron and cortical mitochondria was studied. When neuron was exposed to hypoxanthine/xathine oxidase system and vitamin C/CuSO4 system, obvious damage was detected: lactic dehydrogenase(LDH) was released and TBARS content increased. Ebselen (10, 25, 50 mumol.L-1) reduced LDH efflux induced by O2.- and .OH in a dose-dependent manner. As for the TBARS content, from 5 mumol.L-1 to 50 mumol.L-1, ebselen negated its increase, also dose-dependently. Furthermore, ebselen lowered TBARS content of cortical mitochondria treated with O2.- and .OH in a dose-related manner. But ebselen showed no activity of scavenging O2.- and .OH. This suggests that ebselen has direct anti-oxidant activity on neuron and its activity is not achieved by scavenging oxygen free radical.

A study of the relationship between IgG subclass/IgM and idiopathic nephrotic syndrome

In an attempt to elucidate the relationship between serum IgG subclass/IgM ratio and prognosis in different types of idiopathic nephrotic syndrome (INS), 46 cases of treatment responders and 23 cases of either frequent relapse or non-responders were studied. All patients had received renal biopsy. Serum IgG subclass/IgM ratios were compared between the acute nephrotic phase and remission. The association between therapeutic effect and the parameters of INS were also investigated. There were 24 cases of minimal change nephrotic syndrome (MCNS), 32 cases of IgM nephropathy (IgMN) and 13 cases of focal segmental glomerular sclerosis (FSGS). All cases of MCNS were steroid-responders. Seventeen cases of IgMN experienced frequent relapses. The other 15 cases were responsive to the treatment. 6 cases of FSGS had poor response to any therapy; 7 cases were responsive to either triple therapy or cyclosporine A plus prednisolone. Both IgGI/IgM and IgG2/IgM were correlated with serum albumin and cholesterol levels at the acute nephrotic phase (p < 0.05). Longitudinal change of the immunologic parameters in patients with INS revealed significantly elevated serum IgM level decreased serum IgG level, IgG/IgM, IgG1/IgM, IgG2/IgM, IgG3/IgM, IgG4/IgM and IgG/IgE ratio during acute nephrotic phase. Correlation between therapy responses showed that, for serum IgG1/IgM ratio > 3.0, most of the cases were treatment-responders. For IgG1/IgM ratio > 1.0, all the cases were frequent relapsers or non-responders. These results suggest the immunologic changes in patients of INS may be caused by immune regulatory abnormality. Serum IgG1/IgM ratio may serve as one of the therapeutic and prognostic guides, especially if the patient refuses renal biopsy.

Single-stranded DNA binding protein from bacteriophage cf: characterization, gene localization and protein-ssDNA complex

The single-stranded DNA binding protein from the filamentous bacteriophage cf has been purified and characterized. The first 12 amino acids, resulting from the N-terminal amino acid sequencing analysis of the protein, agree with an open reading frame (ORF) on the cf genome. The ORF contains 294 bp and codes for a 98 a.a. protein of molecular weight 10.8 kDa, consistent with the result from the denaturing protein gel analysis. The protein appears to be a homodimer as evident from the apparent molecular weight of about 22 kDa obtained from native protein gel analysis. The gene location of the protein has been identified as gene V of the cf single stranded genome, same as that from the M13 phage. The GVP of cf shows a strong sequence homology to the ssDNA binding proteins of Ff, IKe and Pf3 filamentous phages. The DNA binding wing of GVP, conserved among the filamentous phages, has been predicted for cf. To further characterize the protein, the GVP-ssDNA complex of cf has been purified from the infected host (Xanthomonas campestris pv. citri) by density gradient centrifugation. Transmission electron microscopy (TEM) images of the complex showed that it is about 1200 nm in length and 9 nm in diameter and it has a highly regular morphology with a central groove shadow running along the entire structure, but without any apparent helical pattern seen in the M13 complex. The GVP-ssDNA complex of cf seems more rigid than that of M13. Our computer modeling study suggested that this difference between the two complexes may be due to the additional 11 or 12 amino acids at the C-terminal end of the cf-GVP.

Technetium-99m-DMSA renal SPECT in diagnosing and monitoring pediatric acute pyelonephritis

This study compares the sensitivity of 99mTc-dimercaptosuccinic acid (DMSA) renal SPECT with planar scintigraphy, concluding the importance of 99mTc-DMSA renal SPECT for the early diagnosis of acute pyelonephritis (APN) in patients under 3 yr of age.

METHODS

Twenty-seven children under 3 yr of age, with clinical and/or laboratory suspicion of APN, were investigated. All 99mTc-DMSA renal SPECT and planar images and voiding cystoureterogram (VCUG) were obtained within 3 days of hospitalization.

RESULTS

In the first examination, renal cortical defects were detected in 23 patients (42 kidneys) with SPECT and in 9 patients (11 kidneys) with planar scintigraphy. One year after treatment, constant renal cortical lesions were observed in 11 patients (14 kidneys) with SPECT and 4 patients (4 kidneys) with planar scintigraphy. The high grades of vesicoureteral reflux (VUR) (grade >or= 3) correlate better with APN diagnosed by SPECT (34 kidneys) than by planar scintigraphy (8 kidneys). Multiple renal cortical defects (number of lesions >or= 4) were only seen in patients under 1.5 yr old and none of those with a negative 99mTc-DMSA renal SPECT had a positive 99mTc-DMSA renal planar scintigraphy at any time. There is a significant difference (p < 0.05) between the diagnostic ability of these two methods of examination.

CONCLUSION

Our results suggest that 99mTc-DMSA renal SPECT should be used, where possible, instead of planar DMSA in routine examination of children with clinical suspicion of APN, especially for those under 3 yr of age.