A multi-site study on the impact of an advance care planning workshop on attitudes, beliefs and behavioural intentions over a 6-month period

BACKGROUND

This study evaluated the impact of the adapted version of the Respecting Choices® The Living Matters Advance Care Planning (ACP) facilitator training programme on trainees' attitudes on facilitation 6 months post-training.

SETTING AND PARTICIPANTS

Two hundred and twenty-one healthcare professionals consisting of doctors, nurses, medical social workers from different training venues in Singapore participated in the first phase of the study (pre- and post) of which 107 participated in the second phase 6 months later (follow-up).

METHODS

Participants self-rated their attitudes, beliefs and behavioural intentions through surveys at three time points in an evaluation design that utilised repeated measures one-way ANOVA (pre-, post-, follow-up). Between-group differences were also examined using independent t-test.

RESULTS

At follow-up, mean scores increased significantly in understanding, confidence, and competence. Changes in effect sizes were large. Although trainees continued to think that ACP is emotionally draining for facilitators, more than before, facilitation experience was considered pleasant for themselves with the positive change significant and moderate in effect size. Those who had experience completing/initiating ACP significantly held more positive views than those who did not.

CONCLUSIONS

The ACP facilitator training programme had lasting effects on enhancing the understanding, competence, and confidence of trainees. Importantly, findings showed that experience in actual facilitation within 6 months after training was important and giving trainees opportunities to facilitate is recommended.

P1604Validating previously reported Brugada syndrome-associated common variants identified in caucasian population in the Han Chinese BrS cohort in Taiwan: SADS-BrS registry

Background

Brugada syndrome (BrS) is a sudden arrhythmic death. The prevalence of BrS is higher in the Southeast Asian populations than that in Caucasian patients. A previous genome-wide association study (GWAS) has reported 13 SNPs significantly associated with BrS. However, no study was performed to validate whether these SNPs are enriched in BrS patients in Han Chinese (HC).

Purpose

Evaluating the common variants previously reported in Caucasian BrS patients could be generalized to HC BrS patients in Taiwan

Methods

We genotyped 200 unrelated BrS patients using Affymetrix TWB Array (N=653,291 SNPs, a customized array for HC in Taiwan). The controls are obtained from the Taiwan Biobank (N ≈ 16,000) using the same array. An imputation workflow was shown in Figure 1. To confirm the accuracy of the imputed genotype of each variant, Sanger sequencing was performed in 10% of randomly selected cases.

Results

Among the 3 most important common variants (rs11708996 in SCN5A, rs10428132 in SCN10A and rs9388451 in HEY2/NCOA7) reported in the previous GWAS mainly conducted in Caucasian BrS patients, 2 of them (rs10428132 and rs9388451) were successfully replicated in the HC population in Taiwan (P<0.01). We also found that the differences of minor allele frequency (dMAF: the MAF of cases minus the MAF of controls) of the two variants were relatively smaller between the BrS cases and healthy controls in HC population compared with that in Caucasian populations (dMAF, rs9388451: 0.15 (Caucasian) vs −0.07 (HC); rs10428132: 0.28 (Caucasian) vs 0.11 (HC)). For the remaining 10 common variants reaching genome-wide significance (P=5×10–8) in Caucasian BrS patients, 9 of them were also significantly enriched in the HC BrS patients after the Bonferroni correction (P<0.05/12=0.0042). We next analyzed the variants identified in the previous GWAS on ECG traits (PR interval, QRS duration, QTc interval, and heart rate) in the Caucasian population. Among the reported 75 variants associated with ECG traits, 5 common variants (rs6798015 (PR), rs1760876 (QRS), rs6795970 (PR/QRS), rs2074238 (QTc) and rs314370 (heart rate)) were significant after Bonferroni correction (P<0.05/75=0.00066).

Figure 1

Conclusions

The preliminary results indicated that 85% of common variants of SCN10A and HEY2/NCOA7 previously reported in Caucasian BrS patients are replicated in BrS patients in the HC population but not the common variant of SCN5A (rs11708996). Furthermore, the common variants of SCN10A and HEY2/NCOA7 related to cardiac depolarization or repolarization may also contribute to the development of BrS.

Acknowledgement/Funding

NTUH 106-S3469, NTUH106-S3458 and NTUH 106-018

[Detection and Analysis of the peripheral lymphocytes micronucleus rate of radiation workers in a city]

Objective: To perform lymphocyte micronucleus analysis on radiation workers with long-term exposure to low doses ionizing radiation, Evaluate the health condition of radiation workers, and provide the evidence for strengthening surveillance of radiation workers. Methods: From January 1, 2013 to December 21, 2016, a statistical analysis and evaluation was conducted of the peripheral lymphocytes micronucleus rate in 5 901 radiation workers who had undergone medical examinations of employees at Chinese Academy of Medical Sciences Institute of Radiation Medicine. Results: The micronucleus rates in radiation workers of the on-job group were higher than the pre-job group (P<0.01) . Significant difference was found among the different sex (t=5.97) , different types (χ(2)=378.69) , different levels of work units (χ(2)=115.48) . Significant difference was found among the micronucleus rates of 672 radiation workers of the on-job group from 2013 to 2016 (χ(2)=92.57, P<0.01) . Conclusion: The peripheral lymphocytes micronucleus rate of radiation workers were significantly higher than non-contact workers. Significant increasing trend of micronucleus rates was noted among the radiation worker with increasing exposure time. The peripheral lymphocytes micronucleus rates of interventional therapy workers were highest. The peripheral lymphocytes micronucleus rates of Private hospitals workers were highest. This phenomenon deserves attention. Protection needs to be strengthened to ensure the health of radiation workers.

Percutaneous kyphoplasty versus posterior spinal fixation with vertebroplasty for treatment of Kümmell disease: A case-control study with minimal 2-year follow-up

This is a retrospective case-control study.The aim of this study was to compare the surgical results of percutaneous kyphoplasty (KP) and posterior spinal fixation with vertebroplasty (PSF+VP) for treatment of Kümmell disease (KD).KD is rare form of post-traumatic delayed avascular necrosis of the vertebral body. It is reported that KP is an effect measure for treatment of KD. Some studies have recommended posterior spinal fixation with vertebroplasty for KD.A total of 100 patients with KD who underwent spinal surgery at our hospital were enrolled from January 2008 to December 2013. The inclusion criteria were monosegment lesion without neurological deficit; the segments are restricted to T11-L2; conservative treatment is invalid. The exclusion criteria were metastatic spinal tumors, infection, primary bone tumor, and multiple myeloma; bisegments and multi-segments; patients with neurological symptoms; the defect of posterior wall of vertebral body; the occupying of vertebral canal. The symptomatic vertebrae were restricted to T11-L2. Patients who were followed-up for less than 2 years after surgery were excluded. Finally, there are 25 patients in the KP group and 21 in the PSF+VP group. There were no significant differences in patient age, disease duration, or the length of follow-up between the 2 groups.Operative time (43.2 ± 21.8 vs 230.6 ± 87.1 minutes) was significantly longer and bleeding volume (5.3 ± 3.1 vs 215.0 ± 170.2 mL) significantly greater in the PSF+VP group. No significant difference between the 2 groups was observed in Visual analog scale score (VAS) (1.3 ± 0.9 vs 1.2 ± 0.9), Oswestry disability index score (ODI) (27.2 ± 9.0 vs 26.0 ± 6.3), and Cobb angle (17.0 ± 7.2 vs 16.5 ± 2.8). KP resulted in a shorter operation time, less bleeding volume, and fewer postoperative complications than PSF+VP.This study shows that both treatments KP and PSF+VP for KD can be safe and effective for the patients with monosegment lesion and without neurological deficit. However, KP show the advantages in a shorter surgical duration, less blood loss, and fewer postoperative complications.

A morphometric study of the middle and lower cervical vertebral endplates and their components

Cervical disc arthroplasty is a common method of treating cervical degenerative disease. However, the footprints of most prosthesis dimensions are obtained from data of Caucasian individuals. Besides, there is a large discrepancy between footprints of currently available cervical disc prostheses and anatomic dimensions of cervical endplates. We aimed to detail the three-dimensional (3D) anatomic morphology of the subaxial cervical vertebral endplate, utilizing high-precision, high-resolution scanning equipment, and provide a theoretical basis for designing appropriate disc prostheses for Chinese patients.A total of 138 cervical vertebral endplates were studied. Each endplate was digitized using a non-contact optical 3D range scanning system and then reconstructed to quantify diameters and surface area for the whole endplate and its components (central endplate and epiphyseal rim). The whole endplate and mid-plane concavity depth were measured.There is marked morphologic asymmetry, in that the cranial endplate is more concave than the corresponding caudal endplate, with endplate concavity depths of 2.04 and 0.69 mm, respectively. For the caudal endplates, the endplate concavity apex locations were always located in the posterior portion (81.42%), while in cranial endplates relatively even. The central endplate was approximately 60% of the area of the whole endplate and the anterior section of the ring was the widest. From C3/4 down to C6/7 discs, the vertebral endplate gradually became more elliptical. Chinese cervical endplate anatomic sizes are generally smaller than that of Caucasians. Although Korean and Chinese individuals both belong to the Asian population subgroup, the majority of anatomic dimensions differ. Singaporean cervical endplate morphology is very similar to that of Chinese patients.We performed a comprehensive and accurate quantitative description of the cervical endplate, which provide references to shape and profile an artificial cervical disc without sacrificing valuable bone stock. To design a device with footprint as large as possible to distribute the axial load, we suggest that additional attention should be paid to the marginal rim. It is essential to specifically design appropriate disc prosthesis for Chinese patients. To fit the morphologic and biomechanical variations, we also propose that the disc prostheses for different vertebral segments should be separately designed.

Can tranexamic acid reduce blood loss in cervical laminectomy with lateral mass screw fixation and bone grafting: a retrospective observational study

To assess the safety and efficacy of tranexamic acid (TXA) for decreasing perioperative blood loss in cervical laminectomy with lateral mass screw fixation and bone grafting (CLF), in which all surgical procedures are identical.From November 2014 to April 2016, we performed a retrospective comparative analysis of 119 patients with multilevel cervical spondylotic myelopathy who had undergone a CLF from C3 to C6 in our center. All surgeries were performed on the patients using a consistent, standard procedure. Patients were divided into control (46) and TXA (73) groups according to whether or not they had received TXA treatment before and during surgery. Demographic profiles of patients such as gender, age, body weight, height, and body mass index were collated and differences between the 2 groups compared. Preoperative and postoperative hematological data in addition to intraoperative and postoperative blood loss were compared between the 2 groups. Additionally, any complications of TXA were also evaluated to assess safety.There was no statistically significant difference in demographic traits between the 2 groups. Intraoperative blood loss in the TXA group (179.66 ± 81.45 mL) was significantly lower than that of the control group (269.13 ± 94.68 mL, P < 0.001), as was postoperative blood loss (108.08 ± 44.31 and 132.83 ± 49.39 mL, respectively; P = 0.005). Total blood loss in the TXA group (287.74 ± 115.40 mL) was also significantly lower than that of the control group (401.96 ± 127.88, P < 0.01). No major intraoperative complications occurred in any of the cases.TXA significantly reduced perioperative blood loss in CLF with no major side effects.

A new cervical artificial disc prosthesis based on physiological curvature of end plate: a finite element analysis

STUDY DESIGN

The study aimed to build a new cervical artificial disc C3-C7 segment prosthesis, and perform a biomechanical comparison between the new prosthesis and the Prestige LP prosthesis using a three-dimensional non-linear finite element (FE) model.

PURPOSE

The study compared the biomechanical differences between the new cervical artificial disc prosthesis based on the physiological curvature of the end plate and the Prestige LP prosthesis after artificial disc replacement.

BACKGROUND CONTEXT

There has been no prior research on artificial disc prostheses based on the physiological curvature of the end plate; studies of biomechanical changes after cervical disc arthroplasty (CDR) are few.

METHODS

An FE model of the C3-C7 segments was developed and validated. A new cervical artificial disc prosthesis based on the physiological curvature of the end plate and the Prestige LP prosthesis were integrated at the C5-C6 segment into the validated FE model. All models were subjected to a follower load of 73.6 N and a 1 Nm in flexion-extension, lateral bending, and axial torsion. The segmental range of motion (ROM) and stress on the prostheses were analyzed.

RESULTS

The ROM in most segments after CDR with new cervical artificial disc prosthesis was more similar to that of the normal cervical spine than the Prestige LP prosthesis. However, there was no significant difference between the two prostheses. The stress on the new artificial disc was significantly less than that in the Prestige LP prosthesis.

CONCLUSIONS

There was no significant difference in ROM in all segments after CDR for the two prostheses. The stress on the new cervical artificial disc prosthesis based on the physiological curvature of the end plate was significantly less than that in the Prestige LP prosthesis. The new artificial disc prosthesis is feasible and effective, and can reduce the implant-bone interface stress on the end plate, which may be one of the causes of prosthesis subsidence.

Biomechanical Analysis of a Novel Prosthesis Based on the Physiological Curvature of Endplate for Cervical Disc Replacement

STUDY DESIGN

Biomechanical analysis of a novel prosthesis based on the physiological curvature of endplate was performed.

OBJECTIVE

To compare the biomechanical differences between a novel prosthesis based on the physiological curvature of the endplate and the Prestige LP prosthesis after cervical disc replacement (CDR).

SUMMARY OF BACKGROUND DATA

Artificial disc prostheses have been widely used to preserve the physiological function of treated and adjacent motion segments in CDR, while most of those present a flat surface instead of an arcuate surface which approximately similar to anatomic structures in vivo. We first reported a well-designed artificial disc prosthesis based on the physiological curvature of the endplate.

METHODS

Three motion segments of 24 ovine cervical spines (C2-5) were evaluated in a robotic spine system with axial compressive loads of 50N. Testing conditions were as follows: 1) intact, 2) C3-4 CDR with artificial disc prosthesis based on the physiological curvature of the endplate, and 3) C3-4 CDR with the Prestige LP prosthesis. The range of motion (ROM) and the pressures on the inferior surface of the two prostheses were recorded and analyzed.

RESULTS

As compared to the intact state, the ROM of all three segments had no significant difference in the replacement group. Additionally, there was no significant difference in ROM between the two prostheses. The mean pressure on the novel prosthesis was significantly less than the Prestige LP prosthesis.

CONCLUSION

ROM in 3 groups (intact group, CDR group with novel prosthesis and CDR group with Prestige LP) showed no significant difference. The mean pressure on the inferior surface of the novel prosthesis was significantly lower than the Prestige LP prosthesis. Therefore, the novel artificial disc prosthesis is feasible and effective, and can reduce the implant-bone interface pressure on the endplate, which may be one possible reason of prosthesis subsidence.

The Role of Posterior Longitudinal Ligament in Cervical Disc Replacement: An Ovine Cadaveric Biomechanical Analysis

Background

Cervical disc replacement (CDR) has been widely used to restore and maintain mobility and function of the treated and adjacent motion segments. Posterior longitudinal ligament (PLL) resection has been shown to be efficient in anterior cervical decompression and fusion. However, less is known about the biomechanical effect of PLL removal versus preservation in cervical disc arthroplasty.

Material/Methods

Three motion segments of 24 ovine cervical spines (C2–C5) were evaluated in a robotic spine system with axial compressive loads of 50 N. These cervical spines were divided in three groups according to the following conditions: (1) intact spine, (2) C3/C4 CDR with the Prestige LP prosthesis and PLL preservation, and (3) C3/C4 CDR with the Prestige LP prosthesis and PLL removal. The ranges of motion (ROMs) were recorded and analyzed in each group.

Results

The C3/C4 ROM in group 3 (CDR with PLL removed) increased significantly in flexion-extension and axial rotation compared with group 1 (intact spine). Moreover, in flexion-extension, the mean total ROM was significantly larger in group 3 than in group 1. All the ROM observed in group 2 (CDR with PLL preserved) did not significantly differ from the ROM observed in group 1.

Conclusions

Compared with intact spines, CDR with PLL removal partly increased ROM. Moreover, the ROM in CDR with PLL preservation did not significantly differ from the ROM observed in intact spines. The PLL appears to contribute to the balance and stability of the cervical spine and should thus be preserved in cervical disc replacement provided that the posterior longitudinal ligament is not degenerative and the compression can be removed without PLL takedown.

Genetic analyses of Xianbei populations about 1,500-1,800 years old

To understand the profile of genetic structure of Xianbei and trace its impacts on the formation and development of the minorities from northern China, we analyzed the sequences of the hypervariable segment I (HVS-I, 16.035-16.398) in mtDNA control region of 17 Tuoba Xianbei remains from Shangdu Dongdajing cemetery (Inner Mongolia). Its haplotype diversity and nucleotide diversity were 0.971 ± 0.032 and 0.0184 ± 0.010, respectively, and the haplogroup status presented 29.5% C, 23.5% D4, 17.6% D5, 17.6% A, 5.9% B and 5.9% G. When the data from Qilang Mountain Tuoba remains and other relevant populations were considered, we found that Dongdajing Tuoba Xianbei presented the closest genetic affinity to Qilang Mountain Tuoba Xianbei. Tuoba Xianbei and Murong Xianbei showed a significant differentiation in the maternal lineages. Tuoba Xianbei may contribute to the gene pool of some northern minorities, and it may mix with Xiongnu in northern China.

Adenovirus-mediated siRNA targeting TNF-α and overexpression of bone morphogenetic protein-2 promotes early osteoblast differentiation on a cell model of Ti particle-induced inflammatory response in vitro

Wear particles are phagocytosed by macrophages and other inflammatory cells, resulting in cellular activation and release of proinflammatory factors, which cause periprosthetic osteolysis and subsequent aseptic loosening, the most common causes of total joint arthroplasty failure. During this pathological process, tumor necrosis factor-alpha (TNF-α) plays an important role in wear-particle-induced osteolysis. In this study, recombination adenovirus (Ad) vectors carrying both target genes [TNF-α small interfering RNA (TNF-α-siRNA) and bone morphogenetic protein 2 (BMP-2)] were synthesized and transfected into RAW264.7 macrophages and pro-osteoblastic MC3T3-E1 cells, respectively. The target gene BMP-2, expressed on pro-osteoblastic MC3T3-E1 cells and silenced by the TNF-α gene on cells, was treated with titanium (Ti) particles that were assessed by real-time PCR and Western blot. We showed that recombinant adenovirus (Ad-siTNFα-BMP-2) can induce osteoblast differentiation when treated with conditioned medium (CM) containing RAW264.7 macrophages challenged with a combination of Ti particles and Ad-siTNFα-BMP-2 (Ti-ad CM) assessed by alkaline phosphatase activity. The receptor activator of nuclear factor-κB ligand was downregulated in pro-osteoblastic MC3T3-E1 cells treated with Ti-ad CM in comparison with conditioned medium of RAW264.7 macrophages challenged with Ti particles (Ti CM). We suggest that Ad-siTNFα-BMP-2 induced osteoblast differentiation and inhibited osteoclastogenesis on a cell model of a Ti particle-induced inflammatory response, which may provide a novel approach for the treatment of periprosthetic osteolysis.

Effects of Os inserted layers on the microstructures and magnetic properties of the FePt films

The microstructure and magnetic properties of multilayer [Os(t)/FePt(x)]n films on a glass substrate with a 10 nm Os buffer layer by ion beam sputtering have been studied as a function of the annealing temperatures between 300 and 800 degrees C. Here, t = 0.2, 1 or 5 nm and x varied from 10, 20, 25, 50, to 100 nm with its associated n value of 10, 5, 4, 2, and 1, respectively. No diffusion evidence was found in samples with a thin Os layer and t > or = 1 nm. The average grain size of the multilayer films can be well controlled by both annealing temperature and thickness of the FePt layer by a very thin Os space layer with t > or = 1 nm. The enhancement of H(c) can be understood from the fact that for a FePt film with an Os spacer layers, the increasing number of Os layer will inhibit the grain growth of FePt grains and enriches the grain boundary. We have experimentally demonstrated that even with a very thin 1 nm Os spacer layers, the [Os(t)/FePt(x)]n multilayer films can exhibit good hard magnetic properties and are attractive candidates for ultrahigh density magnetic recording media.

Mandible changes evaluated by computed tomography following Botulinum Toxin A injections in square-faced patients

BACKGROUND

A facial contour that is oval is more pleasing in Asian women. Patients with a square face often seek facial contouring procedures to improve their appearance. Treatment often involves various combinations of Botulinum NeuroToxin A (BoNTA) injections into the masseters and/or mandibular angle resection. Many physicians claim that muscle paralysis with injections alone will decrease pulling on the underlying bone and also treat underlying bony flaring when present. Muscular changes after BoNTA injections have been well documented. However, the effect of BoNTA injections on the underlying mandibular bone morphology has not been studied to the best of the authors' knowledge. The goal of this study was to determine whether there are mandibular changes after masseter injection with botulinum toxin.

METHODS

In this retrospective study of ten female patients seeking treatment for a square face, three-dimensional CT scans were taken before and 3 months after standardized BoNTA injections in bilateral masseters. Mandibular cortex thickness, mandibular bone thickness, and mandibular volume were measured.

RESULTS

Soft-tissue changes were observed but no bony changes were observed 3 months after injections.

CONCLUSIONS

In this study of adult patients, there were no statistically significant mandibular changes 3 months after BoNTA injection. The current theory of mandibular flaring resolution after partial muscle paralysis is not supported by our findings. Therefore, a patient presenting both masseteric hypertrophy and bony flaring will most likely require a combined muscular and bony procedure.

Light extraction efficiency enhancement of GaN-based light emitting diodes on n-GaN layer using a SiO2 photonic quasi-crystal overgrowth

In this paper, GaN-based LEDs with a SiO2 photonic quasi-crystal (PQC) pattern on an n-GaN layer by nano-imprint lithography (NIL) are fabricated and investigated. At a driving current of 20 mA on Transistor Outline (TO)-can package, the better light output power of LED III (d = 1.2 microm) was enhanced by a factor of 1.20. After 1000 h life test (55 degrees C/50 mA) condition, Normalized output power of LED with a SiO2 PQC pattern (LED III (d = 1.2 microm)) on an n-GaN layer only decreased by 5%. This results offer promising potential to enhance the light output power of commercial light-emitting devices using the technique of nano-imprint lithography.

Using autocloning effects to develop broad-bandwidth, omnidirectional antireflection structures for silicon solar cells

In this study, we used the autocloning effect on pyramid structures to develop broad-bandwidth, omnidirectional antireflection structures for silicon solar cells. The angular dependence of reflectance on several pyramid structures was systematically investigated. The deposition of three-layer autocloned films reduced the refractive index gap between air and silicon, resulting in an increase in the amount of transmitted light and a decrease in the total light escaping. The average reflectance decreased dramatically to ca. 2-3% at incident angles from 0 to 60° for both sub-wavelength- and micrometer-scale pyramid structures. The measured reflectance of the autocloned structure was less than 4% in the wavelength range from 400 to 1000 nm for incident angles from 0 to 60°. Therefore, the autocloning technique, combined with optical thin films and optical gradient structures, is a practical and compatible method for the fabrication of broad-bandwidth, omnidirectional antireflection structures on silicon solar cells.

Electron emissions in InAs quantum dots containing a nitrogen incorporation induced defect state: the influence of thermal annealing

With the incorporation of nitrogen (N) into InAs quantum dots (QDs), the carrier distribution near the QD displays electron emissions from a localized N-induced defect state at 0.34 eV and a weak emission at 0.15 eV from the QD. This defect state causes drastic carrier depletion in the neighboring GaAs bottom layer near the QD, which can effectively suppress tunneling emission for the QD excited states. As a result, electrons escape from the QD ground state through thermal emission to near the GaAs conduction band, rather than through thermal emission to the QD first excited state and a subsequent tunneling to the GaAs conduction band, as observed in InAs QDs without N incorporation. Thermal annealing can weaken the defect emission and enhance the QD emission, suggesting a removal of the defect state and a recovery of carriers in the QD. Increasing annealing temperature can significantly decrease the emission time and energy of the QD emission, which is explained by a weakening of tunneling suppression due to the removal of the defect state.

Enhanced light output from a nitride-based power chip of green light-emitting diodes with nano-rough surface using nanoimprint lithography

Enhanced light extraction from a GaN-based power chip (PC) of green light-emitting diodes (LEDs) with a rough p-GaN surface using nanoimprint lithography is presented. At a driving current of 350 mA and with a chip size of 1 mm × 1 mm packaged on transistor outline (TO)-cans, the light output power of the green PC LEDs with nano-rough p-GaN surface is enhanced by 48% when compared with the same device without a rough p-GaN surface. In addition, by examining the radiation patterns, the green PC LED with nano-rough p-GaN surface shows stronger light extraction with a wider view angle. These results offer promising potential to enhance the light output powers of commercial light-emitting devices by using the technique of nanoimprint lithography under suitable nanopattern design.

Survey of computed tomography scanners in Taiwan: Dose descriptors, dose guidance levels, and effective doses

The IAEA and the ICRP recommended dose guidance levels for the most frequent computed tomography (CT) examinations to promote strategies for the optimization of radiation dose to CT patients. A national survey, including on-site measurements and questionnaires, was conducted in Taiwan in order to establish dose guidance levels and evaluate effective doses for CT. The beam quality and output and the phantom doses were measured for nine representative CT scanners. Questionnaire forms were completed by respondents from facilities of 146 CT scanners out of 285 total scanners. Information on patient, procedure, scanner, and technique for the head and body examinations was provided. The weighted computed tomography dose index (CTDI(w)), the dose length product (DLP), organ doses and effective dose were calculated using measured data, questionnaire information and Monte Carlo simulation results. A cost-effective analysis was applied to derive the dose guidance levels on CTDI(w) and DLP for several CT examinations. The mean effective dose +/- standard deviation distributes from 1.6 +/- 0.9 mSv for the routine head examination to 13 +/- 11 mSv for the examination of liver, spleen, and pancreas. The surveyed results and the dose guidance levels were provided to the national authorities to develop quality control standards and protocols for CT examinations.

Protein phosphatase inhibitor cantharidin inhibits steroidogenesis and steroidogenic acute regulatory protein expression in cultured rat preovulatory follicles

The effect of cantharidin, a natural toxicant of blister beetles and a strong inhibitor of protein phosphatases types 1 and 2A, on luteinizing hormone (LH)-induced synthesis of steroidogenic acute regulatory (StAR) protein was studied in a serum-free culture of preovulatory follicles. StAR protein is a steroidogenic tissue-specific, hormone-induced, rapidly synthesized protein previously shown to be involved in the acute regulation of steroidogenesis, probably by promoting the transfer of cholesterol to the inner mitochondrial membrane and the cytochrome P450 side-chain cleavage (P450scc) enzyme. Treatment of preovulatory follicles dissected from ovaries of immature rats primed with pregnant mares' serum gonadotropin (10 IU) with LH for 24 h resulted in a dose-dependent increase in the level of StAR protein that reached a maximum at 100 ng LH/ml. This increase was associated with an increase in progesterone production. Treatment of follicles with increasing concentrations (10 - 1000 ng/ml) of cantharidin suppresssed LH (100 ng/ml)-induced StAR protein levels and progesterone production in a dose-dependent manner. The amount of P450scc protein and the conversion of 22R-hydroxycholesterol to progesterone were not affected by cantharidin. This indicates that cantharidin did not interfere with the activity of P450scc. Cantharidin also decreased StAR protein levels and progesterone production induced by the adenylate cyclase activator forskolin (10(-5) M) or a cAMP analog 8-Br-cAMP (0.5 mM). These results demonstrate that cantharidin inhibits the LH-induced StAR protein levels, and, thus, suggest that phosphoprotein phosphatase activity is required for the cAMP-protein kinase A-stimulated steroidogenic activity of the preovulatory follicle.

Comparison of speech results after Furlow palatoplasty and von Langenbeck palatoplasty in incomplete cleft of the secondary palate

BACKGROUND

Due to many confounding factors, it is not easy to answer which method of cleft repair is superior to others. The purpose of this study is to try to compare the treatment result of different types of palatoplasty in patients who had the same cleft type and same treatment protocol besides the method of cleft repair. We selected nonsyndromic patients with incomplete cleft of the secondary palate. The speech results after the two palatoplasties were compared.

METHODS

Ninety-six children with nonsyndromic incomplete clefts of the secondary palate who received palatoplasty at the Craniofacial Center of Chang Gung Memorial Hospital from 1989 to 1997 were studied. Forty-six patients received Furlow palatoplasty and 50 patients received von Langenbeck palatoplasty. Velopharyngeal function was evaluated by speech pathologists periodically after the patient was two and half years old. Adequacy of velopharyngeal function was used as a measurement of speech outcome.

RESULTS

The Furlow palatoplasty group showed excellent results with 98% (45/46) adequacy in velopharyngeal function. In the von Langenbeck palatoplasty group, only 70% (35/50) of the patients had adequate velopharyngeal function. Statistical analysis with Fisher's exact test showed a significant difference (p < 0.0001, p < 0.05). Only one patient had an oronasal fistula after Furlow palatoplasty. After von Langenbeck palatoplasty, one patient had an oronasal fistula and one had wound dehiscence.

CONCLUSION

In this study, there was a better speech outcome after Furlow palatoplasty than von Langenbeck palatoplasty for repair of incomplete cleft of the secondary palate. Also, the number of complications after a Furlow palatoplasty was low. It should be a recommended treatment.

Dexamethasone enhances follicle stimulating hormone-induced P450scc mRNA expression and progesterone production in pig granulosa cells

The effect of dexamethasone on follicle-stimulating hormone (FSH)-stimulated expression of cholesterol side-chain cleavage (P450scc) enzyme and production of progesterone by ovarian granulosa cells was studied in vitro. Granulosa cells from 3- to 5-mm pig antral follicles were cultured for 48 h in the presence or absence of FSH and/or dexamethasone. Treatment with FSH resulted in a dose-dependent increase in the level of P450scc mRNA that reached a submaximum at 100 ng FSH/ml. This increase was associated with an increase in progesterone production. Treatment of the cells with increasing concentrations (10(-9)-10(-6) M) of dexamethasone for 48 h increased constitutive and potentiated FSH-stimulated P450scc mRNA levels and progesterone production in a dose-dependent manner. Increasing duration (12-48 h) of treatment with dexamethasone (100 nM) led to a time-dependent increase in basal and FSH-stimulated progesteorne production, achieving statistical significance by 48 and 24 h, respectively. Dexamethasone also increased P450scc mRNA level and progesterone production induced by the adenylate cyclase activator forskolin (10 microM) or a cAMP analog 8-Br-cAMP (1 mM). The effects of dexamethasone on FSH-induced progesterone production were blocked by cotreatment of the cells with glucocorticoid receptor antagonist RU-486. These results demonstrate that dexamethasone potentiates FSH actions on steroidoogenesis in the pig ovary. Possible mechanisms for this potentiation include the ability of dexamethasone to stimulate P450scc gene expression.

Comparison of protein loaded poly(epsilon-caprolactone) microparticles prepared by the hot-melt technique

This study was systematically designed to compare bovine serum albumin (BSA) loaded poly(epsilon-caprolactone) (PCL) microparticles based on a 2(3) factorial experiment. The microparticles were prepared by the holt-melt technique without using an organic solvent for polymer solubilization. The influence of the particle size of protein, protein/polymer ratio, and hydrophilic PEG on the surface morphology, particle size as well as the yield of PCL microparticles, encapsulation efficiency of BSA, and in vitro release properties were investigated. The structure of BSA remained its integrity using this technique. The mean particle size of BSA-loaded microparticles were in the range of 12.7 +/- 0.1-16.9 +/- 0.8 microm, and all of the particles were smooth on the surface. The production yield of microparticles and the encapsulation efficiencies were high, and the values were in the range of 94.8 +/- 1.6%-98.1 +/- 1.0% and 94.9 +/- 9.6%-98.6 + 0.3%, respectively. The burst release of BSA was in the range of 8.2 +/- 0.4%-61.0 +/- 0.8%, which strongly depended on the formulation. None of three variables affected the yield of microparticles prepared from eight formulations (p > 0.05). However, the particle size of BSA significantly affected the size and the burst release as well as the cumulative release of protein in these microparticles (p < 0.05). The initial loading of BSA in terms of BSA/PCL ratio and the amount of PEG blended with PCL significantly affected all of the properties, except the yield (p < 0.05). The smaller the particle size of the BSA, the smaller the size of the resulting microparticles. Since the total surface area of the small particles was larger than that of the large particles, this accounted for the high burst release of protein from the microparticles encapsulating triturated-BSA.

Dual effect of the antianginal drug fendiline on bladder female transitional carcinoma cells: mobilization of intracellular CA2+ and induction of cell death

The effect of fendiline, an antianginal drug, on cytosolic free Ca2+ levels ([Ca2+]i) in populations of bladder female transitional carcinoma (BFTC) cells was explored using fura-2 as a Ca2+ indicator. Fendiline at concentrations between 3 and 200 micromol/l increased [Ca2+]i in a concentration-dependent manner and the signal saturated at 100 micromol/l. The [Ca2+]i signal was biphasic, with an initial rise and a slow decay. Ca2+ removal inhibited the Ca2+ signal by about half in peak amplitude. Adding 3 mmol/l Ca2+ increased [Ca2+]i in cells pretreated with 100 micromol/l fendiline in Ca2+ -free medium, suggesting that fendiline induced Ca2+ influx via capacitative Ca2+ entry. In Ca2+ -free medium, pretreatment with 1 micromol/l thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) to deplete the endoplasmic reticulum Ca2+ store inhibited most of the 100 micromol/l fendiline-induced internal Ca2+ release; and conversely, pretreatment with 100 micromol/l fendiline partly inhibited 1 micromol/l thapsigargin-induced Ca2+ release. This indicates that the major internal Ca2+ store of fendiline-induced [Ca2+]i increases is located in the endoplasmic reticulum. The Ca2+ release induced by 100 micromol/l fendiline may be partly mediated by inositol 1,4,5-trisphosphate, because the [Ca2+]i increase was inhibited by 50% by inhibiting phospholipase C with 2 micromol/l U73122. Fendiline (100 micromol/l) decreased cell viability by 12-44% after being added to cells for 2- 30 min. Together, the findings indicate that in BFTC cells, fendiline exerts a dual effect: mobilization of intracellular Ca2+ and induction of cell death.

Fendiline, an anti-anginal drug, increases intracellular Ca2+ in PC3 human prostate cancer cells

BACKGROUND

The effects of the anti-anginal drug fendiline on intracellular Ca2+ concentrations ([Ca2+]i) in human PC3 prostate cancer cells were examined.

METHODS

[Ca2+]i was measured using the fluorescent dye fura-2.

RESULTS

Fendiline (0.5-100 microM) increased [Ca2+]i in a concentration-dependent manner. Ca2+ removal partly inhibited the Ca2+ signals. In Ca2+-free medium, pretreatment with 100 microM fendiline inhibited most of the [Ca2+]i increase induced by 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), and pretreatment with thapsigargin abolished the fendiline-induced [Ca2+]i increases. Adding 3 mM Ca2+ increased [Ca2+]i in cells pretreated with 0.5-200 microM fendiline in Ca2+-free medium. Pretreatment with 1 microM U73122 to block the formation of inositol-1.4.5-trisphosphate (IP3) did not alter fendiline-induced internal Ca2+ release.

CONCLUSIONS

The anti-anginal drug fendiline induced internal Ca2+ release and external Ca2+ entry. Because prolonged increases in [Ca2+]i may lead to cell injury and death, the long-term effect of fendiline on the function of prostate cancer cells should be investigated.

Lead chelation therapy and urate excretion in patients with chronic renal diseases and gout

BACKGROUND

It is known that chronic renal insufficiency (CRI) patients with gout may have subtle lead poisoning. In addition, gout episodes frequently aggravate progressive renal insufficiency because of the use of nephrotoxic drugs and urate deposition. Our study was arranged to evaluate the causal effect of environmental lead exposure on urate excretion in CRI patients.

METHODS

A cross-section study and a randomized, controlled trial were performed. Initially, 101 patients with CRI and without a history of previous lead exposure received ethylenediaminetetraacetic acid mobilization tests to assess body lead stores (BLS). Then, a clinical trial was performed; 30 CRI patients with gout and high-normal BLS and the changes of urate excretion in these patients were compared before and after lead chelating therapy. The treated group received four-week chelating therapy, and the control group received a placebo therapy.

RESULTS

The BLS of patients with CRI and gout was higher than that of patients with CRI only, and none had subtle lead poisoning. The BLS, not the blood lead level (BLL), significantly correlated to indices of urate excretion in all CRI patients after related factors were adjusted. In addition, after lead chelating therapy, urate clearance markedly improved after a reduction of the BLS of patients with CRI and gout (study group 67.9 +/- 80.0% vs. control group 1.2 +/- 34.0%, P = 0.0056).

CONCLUSION

Our findings suggest that the chronic low-level environmental lead exposure may interfere with urate excretion of CRI patients. Importantly, the inhibition of urate excretion can be markedly improved by lead chelating therapies. These data shed light on additional treatment of CRI patients with gout; however, more studies are needed to confirm our findings.

Mycophenolate mofetil reduces renal cortical inducible nitric oxide synthase mRNA expression and diminishes glomerulosclerosis in MRL/lpr mice

Overexpression of inducible nitric oxide synthase (iNOS) has been implicated in the pathogenesis of lupus glomerulonephritis. Mycophenolate mofetil (MMF), a novel immunosuppressive agent, is currently used in organ transplantation and under evaluation for treatment of autoimmune disorders. Mycophenolic acid, the active metabolite of MMF, has been shown to suppress cytokine-induced nitric oxide production in vitro. The aim of this study was to evaluate the effect of MMF on the expression of renal cortical iNOS mRNA and protection against glomerulonephritis in MRL/lpr mice. Three-month-old MRL/lpr mice (n = 6) displaying clinical symptoms of glomerulonephritis were treated for 3 months with MMF (90 mg/kg/day) dissolved in a vehicle. Controls were age- and sex-matched mice (n = 6) that received the vehicle alone. By reverse-transcription competitive polymerase chain reaction, we found that the renal cortical iNOS/beta-actin mRNA ratio was reduced by 30.8% (P <.05) in MMF-treated mice. Furthermore, MMF significantly reduced urinary nitrite production and degree of glomerulosclerosis. The glomerular volume was reduced by 17.5% (P <.001). Proteinuria was also significantly reduced in the MMF-treated group. However, by electrophoretic mobility shift assay, the nuclear binding of nuclear factor-kappaB (NF-kappaB) was not affected by MMF treatment. We conclude that in addition to its immunosuppressive action, MMF may reduce renal cortical iNOS mRNA expression and diminish glomerulosclerosis in MRL/lpr mice independent of modulation of the NF-kappaB pathway.

In vivo pressure-flow curve in unilateral rat lung ischemia-reperfusion injury

The pressure-flow (P-Q) curve has been widely used in many studies to describe the effects of various factors on vascular hemodynamics. It is not clear, however, whether unilateral ischemia-reperfusion (IR) alters the P-Q curve of the rat lung. In this study, we developed an in vivo P-Q curve using the unilateral (left) rat lung before and after IR. Animals were divided into two groups: sham and IR. The protocol of the IR group consisted of three periods: baseline, ischemia, and reperfusion. P-Q curves were obtained by altering blood flow of the left lung during the baseline and the reperfusion periods. The sham group received the same operation without IR procedure. An additional group was used to compare pulmonary blood flow measured by the microsphere and the ultrasonic methods. IR treatment rotated the P-Q curve toward the left, indicating an increase in resistance in the left lung. However, this rotation was not found in the sham group. A significant correlation (r = 0.87, P < 0.01) between percentages of blood flow obtained by the microsphere and ultrasonic methods in both right and left lungs was demonstrated. Therefore, we demonstrated a simple and useful technique to evaluate changes in the P-Q curves caused by IR in the unilateral rat lung model.

Clomiphene, an Ovulation-Inducing Agent, Mobilizes Intracellular Ca2+ and Causes Extracellular Ca2+ Influx in Bladder Female Transitional Carcinoma Cells

BACKGROUND/METHODS

The effect of clomiphene, an ovulation-inducing agent, on cytosolic free Ca2+ levels ([Ca2+]i) in populations of BFTC human bladder cancer cells was explored by using fura-2 as a Ca2+ indicator.

RESULTS

Clomiphene at concentrations between 10 and 75 microM increased [Ca2+]i in a concentration-dependent manner and the signal saturated at 50 microM. The [Ca2+]i signal was biphasic with an initial rise and a slow decay. Ca2+ removal inhibited the Ca2+ signal by about 40-50% in maximum [Ca2+]i. Adding 3 mM Ca2+ increased [Ca2+]i in cells pretreated with 50 microM clomiphene in Ca2+-free medium, suggesting that clomiphene induced capacitative Ca2+ entry. In Ca2+-free medium, pretreatment with 50 microM brefeldin A (to disrupt the Golgi complex Ca2+ store), 1 microM thapsigargin (to inhibit the endoplasmic reticulum Ca2+ pump), and CCCP (to uncouple mitochondria) inhibited 85% of clomiphene-induced intracellular Ca2+ release. Conversely, pretreatment with 50 microM clomiphene in Ca2+-free medium abolished the [Ca2+]i increase induced by brefeldin, thapsigargin or CCCP. The intracellular Ca2+ release was unaltered by inhibiting formation of inositol-1,4,5-trisphosphate (IP3) with 2 mM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122; a phospholipase C inhibitor).

CONCLUSION

The [Ca2+]i increase induced by 50 microM clomiphene was not affected by 10 microM of nifedipine, verapamil or diltiazem. Collectively, the results suggest that clomiphene releases intracellular Ca2+ in an IP3-independent manner and also activates extracellular Ca2+ influx.

Telomerase is regulated by protein kinase C-zeta in human nasopharyngeal cancer cells

Telomerase, a specialized ribonucleoprotein reverse transcriptase that directs the synthesis of telomeric DNA, is repressed in normal human somatic cells, but is activated in most cancers. Little is known concerning how telomerase activity is activated and maintained in cancer cells. We have shown previously that inhibition of protein kinase C (PKC) decreases the telomerase activity of human nasopharyngeal carcinoma (NPC) cells. Here, we provide evidence that the decrease of telomerase activity by PKC inhibition is not mediated by transcriptional down-regulation of hTERT, the catalytic protein of human telomerase. In vitro phosphorylation studies revealed that exogenous addition of PKC-alpha, -betaI, -delta or -zeta led to restoration of telomerase activity in the crude extracts of PKC-inhibited NPC cells. However, depletion of PKC-alpha and -betaI in vivo had no detectable effect on the telomerase activity of NPC cells. Using antisense oligonucleotides against individual PKC isotypes, we observed that telomerase activity was inhibited only by the antisense oligonucleotide against PKC-zeta but not by those against PKC-alpha, -betaI or -delta. Taken together, these data demonstrate that PKC participates in the regulation of telomerase activity by direct or indirect phosphorylation of telomerase proteins, and that PKC-zeta is the PKC isotype that functions in vivo in the NPC cells.

Environmental lead exposure and progressive renal insufficiency

BACKGROUND

Several recent studies show that serum creatinine level or creatinine clearance is inversely associated with blood lead levels. However, the studies did not allow direct inferences about causality.

OBJECTIVE

To evaluate the relation between body lead burden (BLB) and progressive renal insufficiency in patients without previous heavy lead exposure.

DESIGN

A prospective, longitudinal study with a controlled clinical trial.

PATIENTS

One hundred ten patients with chronic renal insufficiency (serum creatinine level, 133-354 micromol/L [1.5-4.0 mg/dL]) and normal BLB (EDTA mobilization tests, <600 microg per 72-hour urine collection) and without a history of previous heavy lead exposure were divided into 2 groups according to BLB: the high-normal BLB group (BLB > or =80 microg and <600 microg) and the low BLB group (BLB <80 microg). Patients were prospectively followed up for 2 years.

MAIN OUTCOME MEASURES

The primary outcome was a 1.5 times increase in the initial creatinine level. The secondary outcome was a change over time in the value of creatinine clearance. At the end of follow-up, a 3-month clinical trial with chelation therapy for patients with high-normal BLB was performed to clarify the role of environmental lead exposure in progressive renal insufficiency.

RESULTS

Fifteen patients (14 in the high-normal BLB group and 1 in the low BLB group) reached the primary outcome within 24 months. Renal outcome was significantly better in the low BLB group (P<.001). From month 12 to month 24, renal function of high-normal BLB patients had a greater rate of progressive renal insufficiency than that of low BLB patients. In the Cox multivariate regression analysis, BLB was the most important risk factor for determining the progression of renal insufficiency. After chelation therapy, significant improvement in renal function was noted. In addition, the effect of improving renal function lasted for more than 12 months in these patients.

CONCLUSIONS

Long-term low-level environmental lead exposure may subtly affect progressive renal insufficiency in the general population. Progressive renal insufficiency may be improved for at least 1 year after lead chelating therapy. Further investigations are needed to clarify this observation.

Lupus-like kidney disease in mice deficient in the Src family tyrosine kinases Lyn and Fyn

Systemic lupus erythematosus (SLE) is an autoimmune disease whose cause is poorly understood. Mice rendered deficient in specific genes have served as useful animal models in deciphering the genetic control of the disease [1]. We [2] and others [3, 4] previously demonstrated that mice deficient in the Src family tyrosine kinase Lyn developed a mild lupus-like disease with high survival rates. During the course of investigating the functional interaction of Src family kinases, we generated a mouse strain deficient in both Lyn and Fyn. The double-mutant mice died at relatively young ages and developed a severe lupus-like kidney disease. Unlike the double-mutant mice, single mutants deficient in either Lyn or Fyn lived longer and had distinct subsets of the symptoms found in the former. Lyn deficiency led to high levels of autoantibody production and glomerulonephritis, as previously reported [2--4], whereas loss of Fyn contributed to proteinuria by a B and T lymphocyte-independent mechanism. Our data suggest that the severe kidney disease in the double-mutant mice results from a combination of immunological and kidney-intrinsic defects. This new animal model may be informative about the causes of human SLE.

Oxygen- and growth rate-dependent regulation of Escherichia coli fumarase (FumA, FumB, and FumC) activity

Escherichia coli contains three biochemically distinct fumarases which catalyze the interconversion of fumarate to L-malate in the tricarboxylic acid cycle. Batch culture studies indicated that fumarase activities varied according to carbon substrate and cell doubling time. Growth rate control of fumarase activities in the wild type and mutants was demonstrated in continuous culture; FumA and FumC activities were induced four- to fivefold when the cell growth rate (k) was lowered from 1.2/h to 0.24/h at 1 and 21% O(2), respectively. There was a twofold induction of FumA and FumC activities when acetate was utilized instead of glucose as the sole carbon source. However, these fumarase activities were still shown to be under growth rate control. Thus, the activity of the fumarases is regulated by the cell growth rate and carbon source utilization independently. Further examination of FumA and FumC activities in a cya mutant suggested that growth rate control of FumA and FumC activities is cyclic AMP dependent. Although the total fumarase activity increased under aerobic conditions, the individual fumarase activities varied under different oxygen levels. While FumB activity was maximal during anaerobic growth (k = 0.6/h), FumA was the major enzyme under anaerobic cell growth, and the maximum activity was achieved when oxygen was elevated to 1 to 2%. Further increase in the oxygen level caused inactivation of FumA and FumB activities by the high oxidized state, but FumC activity increased simultaneously when the oxygen level was higher than 4%. The same regulation of the activities of fumarases in response to different oxygen levels was also found in mutants. Therefore, synthesis of the three fumarase enzymes is controlled in a hierarchical fashion depending on the environmental oxygen that the cell encounters.

N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride) (W-7) causes increases in intracellular free Ca2+ levels in bladder female transitional carcinoma (BFTC) cells

The effect of N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride) (W-7), a widely used calmodulin inhibitor, on intracellular free Ca2+ levels ([Ca2+]i) in bladder female transitional cancer (BFTC) cells was examined using fura-2 as a Ca2+ dye. W-7 (10-1000 microM) caused an increase in [Ca2+]i in a concentration-dependent manner with an EC50 of 75 microM. The [Ca2+]i response was composed of an initial rise and a sustained plateau without significant decaying during the measurement of 250 seconds. Extracellular Ca2+ removal dramatically decreased the Ca2+ signals by 50-90%. W-7 (100 microM) failed to induce a [Ca2+]i increase in Ca(2+)-free medium after pretreatment with thapsigargin (1 microM), an endoplasmic reticulum Ca2+ pump inhibitor; conversely, W-7 pretreatment abolished the Ca2+ release induced by thapsigargin. Addition of 3 mM Ca2+ increased [Ca2+]i after preincubation with 100 microM W-7 in Ca(2+)-free medium. W-7-induced Ca2+ release was not altered by inhibiting phospholipase C with 2 microM 1-(6-((17b-3-methoxyestra-1,3,5 (10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione) (U73122). Together, this study shows that W-7 caused [Ca2+]i increases in human bladder cancer cells by releasing intracellular Ca2+ from the endoplasmic reticulum and also by causing extracellular Ca2+ influx with the later playing a dominant role. The W-7-induced intracellular Ca2+ release was uncoupled to a prior elevation in intracellular levels of inositol 1,4,5-trisphosphate (IP3).

NPC-15199, a novel anti-inflammatory agent, mobilizes intracellular Ca2+ in bladder female transitional carcinoma (BFTC) cells

This report demonstrates that NPC-15199 [(N-(9-fluorenylmethoxycarbonyl)L-leucine)], a novel anti-inflammatory agent, increases intracellular Ca2+ concentration ([Ca2+]i) in human bladder female transitional cancer (BFTC) cells. Using fura-2 as a Ca2+ probe, NPC-15199 (0.1-2 mM) was found to increase [Ca2+]i concentration-dependently. The response saturated at 2-5 mM NPC-15199. The [Ca2+]i increase comprised an initial rise, a slow decay, and a plateau. Ca2+ removal partly inhibited the Ca2+ signals. In Ca2+-free medium, pretreatment with 1 mM NPC-15199 abolished the [Ca2+]i increase induced by 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor); and after pretreatment with thapsigargin, NPC-15199-induced Ca2+ release was dramatically inhibited. This indicates that NPC-15199 released internal Ca2+ mostly from the endoplasmic reticulum. Adding 3 mM Ca2+ increased [Ca2+]i in cells pretreated with 1 mM NPC-15199 in Ca2+-free medium. Together, the findings suggest that in BFTC bladder cancer cells, NPC-15199 induced Ca2+ release from the endoplasmic reticulum and activating Ca2+ entry.

Ectopic pancreatic rests: a rare cause of persistent umbilical discharge

Ectopic pancreatic rests are rare. We report two cases discovered in infants who underwent surgical exploration of the umbilicus for persistent umbilical discharge with peri-umbilical excoriation. A shallow sinus leading to a firm cyst was excised in both infants, and histopathological study confirmed the presence of exocrine and endocrine pancreatic tissue. There is only one other case of ectopic umbilical pancreatic tissue reported, and this was in a patient presenting with an umbilical mass.

Novel strategy for efficient screening and construction of host/vector systems to overproduce penicillin acylase in Escherichia coli

A novel and simple method of using penicillin for screening of mutant strains with a high penicillin acylase (PAC) activity was developed. Random mutagenesis was conducted using a PAC-producing strain resistant to 6-aminopenicillanic acid (6-APA) as the parent strain and mutants were screened with penicillin at a high concentration. Results suggest that mutants with a high minimum inhibitory concentration for penicillin (MIC(penG)) usually overproduce PAC. Both volumetric and specific PAC activities of a mutant, MD7, were significantly higher than those of the parent strain, HBPAC101 harboring pCLL2902. The mutation(s) resulting in the enhanced expression was mapped on the host chromosome rather than the plasmid. In addition, the mutant strain of MDDeltaP7, derived by elimination of the harbored plasmid in MD7, was demonstrated to be efficient in production of PAC by using the expression plasmids for which expression of the pac gene is limited by translation. An extremely high specific PAC activity of more than 350 U/L/OD(600) was reached upon cultivation of MDDeltaP7 harboring pTrcKnPAC2902 in a bioreactor. As such, the strategy is effective in terms of constructing PAC overproducers and improving the process yield for production of PAC.

Local supplementation of ketoprofen reduces the incidence of low back pain after lumbar epidural anesthesia

BACKGROUND

Backache is a common postoperative complaint after lumbar epidural anesthesia. Our study was aimed to compare the effect of the local addition of ketoprofen on the incidence of postepidural backache after nonobstetric surgery.

METHODS

One thousand patients scheduled for hemorrhoidectomy were randomly given 4 ml of 1% lidocaine with ketoprofen 1:400 (ketoprofen group) or without ketoprofen (control group) for local skin infiltration prior to epidural needle placement. Each of them received a single epidural injection of 25 ml 2% lidocaine with epinephrine 1:200000, and was interviewed 24, 48, and 72 hours postoperatively using a standard visual analog scale (VAS) for evaluation of postepidural backache.

RESULTS

The incidence of postepidural backache in the ketoprofen-group patients for the 3 days was 9.8%, 4.6%, and 1.8%, all rates which were significantly less than those observed in the control-group patients (22.8%, 17.4%, and 9.2%, p < 0.001). There was also a significant association between postepidural backache and multiple attempts at epidural needle insertion.

CONCLUSION

In summary, the local addition of ketoprofen reduced the incidence and severity of postepidural backache.

Pre-dialysis glycemic control is an independent predictor of mortality in type II diabetic patients on continuous ambulatory peritoneal dialysis

OBJECTIVE

To evaluate the impact of pre-dialysis glycemic control on clinical outcomes for type II diabetic patients on continuous ambulatory peritoneal dialysis (CAPD).

MATERIALS AND METHODS

One hundred and one type II diabetic patients receiving CAPD for at least 3 months were enrolled in a single institute. The patients were classified into two groups according to status of glycemic control. In the good glycemic control group, more than 50% of blood glucose determinations were within 3.3-11.0 mmol/L and glycosylated hemoglobin (HbA1C) levels were within 5%-10% at all times. In the poor glycemic control group, less than 50% of blood glucose determinations were within 3.3-11.0 mmol/L, or HbA1C levels were above 10% at least 6 months before peritoneal dialysis was started. In addition to glycemic control status, pre-dialysis serum albumin, cholesterol levels, residual renal function, peritoneal membrane function, and modes of glycemic control were also recorded.

RESULTS

The patients with good glycemic control had significantly better survival than those with poor glycemic control (p < 0.01). There was no significant difference in pre-dialysis morbidity between two groups. No significant differences were observed in patient survival between patients with serum albumin above 30 g/L and those with serum albumin under 30 g/L; between those with cholesterol levels above or below 5.2 mmol/L; and between those with different peritoneal membrane solute transport characteristics as evaluated by a peritoneal equilibration test (PET). Furthermore, there was no significant difference in survival between patients who controlled blood sugar by diet and those who controlled it by insulin. Cardiovascular disease and infection are the major causes of death in both groups. Although good glycemic control predicts better survival, it does not change the pattern of mortality in diabetic patients maintained on CAPD.

CONCLUSIONS

Glycemic control before starting dialysis is a predictor of survival for type II diabetic patients on CAPD. Patients with poor glycemic control predialysis are associated with increased morbidity and shortened survival.

The role of components of recombination signal sequences in immunoglobulin gene segment usage: a V81x model

It has long been appreciated that some immunoglobulin (and T-cell receptor) gene segments are used much more frequently than others. The VHsegment V81x is a particularly striking case of overusage. Its usage varies with the stage of B-cell development and with the strain of mice, but it is always high in B cell progenitors. We have found that the coding sequence and the recombination signal sequences (RSS) are identical in five mouse strains, including CAST/Ei, a strain derived from the species Mus castaneus. Thus, the strain differences cannot be attributed to sequences within V81x itself. V81x RSS mediated recombination at rates significantly higher than another VHRSS. Although the V81x nonamer differs at one base pair from the consensus sequence, an RSS with this nonamer and a consensus heptamer recombines as well as the consensus RSS. When the V81x spacer is replaced by that of VA1, the frequency of recombination decreases by approximately 5-fold; thus, the contribution of variation in natural spacers to variability in VHusage in vivo is likely to be more than has been previously appreciated. Furthermore, the contribution of the heptamer and nonamer to differential VHusage in our assay is correlated inversely with their conservation throughout the VHlocus.

Genetic manipulation to identify limiting steps and develop strategies for high-level expression of penicillin acylase in Escherichia coli

We have identified the bottleneck steps limiting expression of penicillin acylase (PAC) through comparison of the expression performance for various PAC-expression vectors constructed by genetically modulating the efficiencies of transcription and/or translation of the pac gene. To our knowledge, this is the first report demonstrating that expression of PAC could be limited by various steps, such as transcription, translation, and post-translational steps (i.e. translocation and periplasmic processing), depending on the host/vector systems. Results also indicate that the structure of the wild-type pac gene might not be optimal for direct use in production of PAC using recombinant DNA technology. To improve the gene expression, transcription was enhanced by manipulating certain DNA bases in the pac regulatory region, whereas translation was enhanced by enlarging the spacing between the ribosome binding site and the ATG initiation codon to increase the initiation efficiency. The information is useful in terms of developing genetic strategies for overproduction of recombinant PAC in Escherichia coli.

Risk of gonadoblastoma in female patients with Y chromosome abnormalities and dysgenetic gonads

We report two female patients with gonadal dysgenesis and sex chromosome mosaicism involving the Y chromosome. Conventional karyotyping was supplemented with fluorescent in situ hybridisation techniques in order to confirm the presence of Y chromosomes. One patient is a phenotypic female with karyotype 45,X/46,X,idic(Y)(q11.2). She underwent a laparoscopic gonadectomy at which streak ovaries without evidence of gonadoblastoma were removed. The second patient presented as a virilised female with karyotype 45,X/47,XYY. At laparoscopy, she was found to have mixed gonadal dysgenesis with a gonadoblastoma in situ. We recommend early gonadectomy in female children presenting with gonadal dysgenesis and the presence of a Y chromosome although once the gonadoblastoma locus on Y chromosome gene has been cloned it may be possible to identify those patients who have a low risk of developing gonadoblastoma.

Manipulation of carbon assimilation with respect to expression of the pac gene for improving production of penicillin acylase in Escherichia coli

A strategy of genetically manipulating carbon assimilation with respect to expression of the pac gene was employed for overproduction of recombinant penicillin acylase (PAC). Two expression plasmids of pCLL2902 and pCLL3201, which contain the pac coding region but differ in the pac regulatory region, were constructed for the production experiments. Expression of the pac gene was subjected to phenyl acetic acid (PAA-) induction and glucose catabolite repression for pCLL3201, whereas it was subjected to neither of the two transcriptional regulations for pCLL2902. The specific PAC activity for strains harboring pCLL2902 was significantly higher than that for strains harboring pCLL3201 due to an improved transcription efficiency. In addition, no inclusion bodies were observed upon production of PAC using the current expression systems. The results suggest that using the native pac promoter instead of a strong promoter such as tac for regulation is a feasible approach for production of PAC. The impact of the current expression systems is also significant from a process viewpoint since, using strains harboring pCLL2902, not only could glucose replace PAA as a carbon source of Escherichia coli cultures for production of PAC but also the volumetric PAC activity was highly improved.

Chelation therapy for patients with elevated body lead burden and progressive renal insufficiency. A randomized, controlled trial

BACKGROUND

Nephropathy is known to occur in persons exposed to high levels of lead, but the question of whether long-term exposure to low levels of environmental lead is associated with impaired renal function remains controversial.

OBJECTIVE

To examine whether chelation therapy slows the progression of renal insufficiency in patients with mildly elevated body lead burden.

DESIGN

Randomized, controlled trial.

SETTING

Academic medical center in Taiwan.

PATIENTS

32 patients with chronic renal insufficiency (serum creatinine level > 132.6 micromol/L [1.5 mg/dL] and < 353.8 micromol/L [4.0 mg/dL]), mildly elevated body lead burden (> 0.72 micromol [150 microg] of lead per 72-hour urine collection and < 2.90 micromol [600 microg] of lead per 72-hour urine collection [EDTA mobilization tests]), and no history of heavy lead exposure.

INTERVENTION

The treatment group received 2 months of chelation therapy; the control group received no therapy.

MEASUREMENTS

The reciprocal of serum creatinine (1/Cr) was used as an index of progressive renal insufficiency.

RESULTS

Rates of progression of renal insufficiency were similar in the treatment group and the control group during a 12-month baseline observation period (1/Cr, 0.000054 L/micromol per month compared with 0.000046 L/micromol per month; P > 0.2). After the 2-month treatment period, improvement in renal function was greater in the treatment group than in the control group. In the 12 months after the treatment period, renal insufficiency progressed more slowly in the treatment group than in the control group (1/Cr, 0.000033 +/- 0.00038 L/micromol per month compared with 0.000045 +/- 0.000038 L/micromol per month; P = 0.0030).

CONCLUSION

Chelation therapy seems to slow the progression of renal insufficiency in patients with mildly elevated body lead burden. This implies that long-term exposure to low levels of environmental lead may be associated with impaired renal function in patients with chronic renal disease.

Differential usage of VH gene segments is mediated by cis elements

Ig diversity is generated in large part by the combinatorial joining of the Ig gene segments, VH, D, and JH, that together encode the variable domain of Ig. The final Ig repertoire, however, not only reflects the diversity generated through V(D)J recombinatorial joining, but it is also the product of a number of developmental restraints and selections. To avoid such restrictions and assess the recombination potential of individual Ig gene segments, we constructed Ig heavy (H) chain microlocus plasmids, each of which contain germline coding, recombination signal, and flanking sequences of a VH, D, and JH gene segment. These plasmids allow us to assess the recombination potential of the segments in the context of their natural flanking DNA sequences, but in the absence of any higher order chromatin structure or cellular selection. We found that the frequency and extent of deletions and additions at the recombination breakpoints are similar to those observed at rearranged Ig H chain loci in intact animals. The relative frequencies of the types of rearrangements--VD-J, V-DJ, VinvD-J (invD = inverted D), and VDJ--however, differ strongly. Moreover, V81x, the most used VH gene segment in intact mice, also is overused in this plasmid assay, 15 to 30 times that of another VH segment. This result indicates that the overuse of V81x in the early B cell repertoire can be a consequence of its DNA sequence and not of cellular activities.

Aminoguanidine reduces glomerular inducible nitric oxide synthase (iNOS) and transforming growth factor-beta 1 (TGF-beta1) mRNA expression and diminishes glomerulosclerosis in NZB/W F1 mice

Over-expression of iNOS is implicated in the pathogenesis of glomerulonephritis in animal models of systemic lupus erythematosus. The aim of this study was to evaluate the effect of aminoguanidine, a selective inhibitor of iNOS, for the protection from glomerulosclerosis in NZB/W F1 mice. Female NZB/W F1 mice (n = 8) were treated with aminoguanidine (1 g/l) in drinking water for 4 months starting at age 2 months before the onset of glomerulonephritis. Controls were age- and sex-matched mice (n = 10) without aminoguanidine treatment. By glomerular microdissection and reverse-transcription competitive polymerase chain reaction, we found that glomerular iNOS/beta-actin and TGF-beta1/beta-actin mRNA ratios were reduced 15.1% (P<0.05) and 61.3% (P<0.01), respectively, in aminoguanidine-treated mice. Aminoguanidine significantly reduced the glomerular iNOS staining, urinary nitrite production and degree of glomerulosclerosis. In addition, the glomerular volume and mean glomerular cell number were reduced 33.2% (P<0.01) and 32.8% (P<0.01), respectively. Likewise, the urinary proteinuria was also significantly reduced by aminoguanidine. These results indicate that administration of aminoguanidine may reduce the progression of glomerulosclerosis in NZB/W F1 mice, possibly through inhibition of glomerular nitric oxide production.

Multifocal retroperitoneal malignant fibrous histiocytoma: a case report

This report concerns a 67-year-old male with malignant fibrous histiocytoma arising from the psoas muscle and perirenal soft tissue. The tumor was considered a mesenchymal neoplasm. These are generally clinically and radiologically indistinguishable from other retroperitoneal tumors. This patient received en bloc resection of the retroperitoneal tumor and radical nephrectomy without adjuvant therapy. He underwent excision of a retroperitoneal cystic mass complicated with lymph leakage one year postoperatively. Discharged in a stable condition after one week of total parenteral nutrition, the patient remains disease-free 16 months postoperatively.