Enhancing Immunomodulatory Function of Mesenchymal Stromal Cells by Hydrogel Encapsulation

Mesenchymal stromal cells (MSCs) showcase remarkable immunoregulatory capabilities in vitro, positioning them as promising candidates for cellular therapeutics. However, the process of administering MSCs and the dynamic in vivo environment may impact the cell-cell and cell-matrix interactions of MSCs, consequently influencing their survival, engraftment, and their immunomodulatory efficacy. Addressing these concerns, hydrogel encapsulation emerges as a promising solution to enhance the therapeutic effectiveness of MSCs in vivo. Hydrogel, a highly flexible crosslinked hydrophilic polymer with a substantial water content, serves as a versatile platform for MSC encapsulation. Demonstrating improved engraftment and heightened immunomodulatory functions in vivo, MSCs encapsulated by hydrogel are at the forefront of advancing therapeutic outcomes. This review delves into current advancements in the field, with a focus on tuning various hydrogel parameters to elucidate mechanistic insights and elevate functional outcomes. Explored parameters encompass hydrogel composition, involving monomer type, functional modification, and co-encapsulation, along with biomechanical and physical properties like stiffness, viscoelasticity, topology, and porosity. The impact of these parameters on MSC behaviors and immunomodulatory functions is examined. Additionally, we discuss potential future research directions, aiming to kindle sustained interest in the exploration of hydrogel-encapsulated MSCs in the realm of immunomodulation.

Reciprocal Donor-Recipient Strain Combinations Present Different Vascularized Composite Allotransplantation Outcomes in Rodent Models

BACKGROUND

Although vascularized composite allotransplantation (VCA) has been the focus of many animal studies, further research is needed to determine the potential for a generalized model and immunosuppression regimen that applies across different donor-recipient combinations. In this study, the authors evaluated the outcome of VCAs performed on reciprocal rodent donor-recipient combinations.

METHODS

VCA was performed in rats using Lewis and Brown Norway (BN) donor-recipient pairs, under the previously reported antilymphocyte serum/cyclosporine/adipose-derived stem cell regimen. Similarly, a published co-stimulatory blockade/rapamycin regimen was performed on the mouse VCA model between Balb/C and C57BL/6 strains.

RESULTS

To accommodate the active behaviors of BN recipients, the allograft had to be modified and inset to the neck instead of to the groin. The tolerogenic regimen did not provide the same benefits for BN rats as it did for Lewis recipients. Increasing antilymphocyte serum dose and extending the duration of cyclosporine administration from 10 to 21 days significantly prolonged allograft survival and induced donor-specific tolerance. In mice, the co-stimulatory blockade/rapamycin regimen produced inferior VCA outcomes in BALB/c recipients than in C57BL/6 recipients. In both rats and mice, the authors identified an association between the tolerance outcome and the peripheral chimerism measured on postoperative day 30.

CONCLUSIONS

Reciprocal donor-recipient combinations led to different responses toward the immunosuppression regimen and varied VCA outcomes. Sustained donor chimerism that remained in circulation for 1 month after surgery supported long-term VCA survival. Modification of the model and immunosuppression regimen accordingly is recommended.

CLINICAL RELEVANCE STATEMENT

Various donor-recipient combinations respond differently to the immunosuppression regimens. Maintaining donor chimerism for 30 days after surgery improves VCA survival. It is recommended to tailor the immunosuppression regimen based on the recipient's background to optimize outcomes.

Bioimaging of alloantigen-stimulated regulatory T cells in rat vascularized composite allotransplantation

Background

Tipping the balance toward regulatory T cells (Tregs) through adoptive cell therapy has shown promise to induce transplantation tolerance. Although such strategy has been explored in many mice organ transplantation studies, less knowledge was available in rat systems. Furthermore, the behaviors of the transferred cells have not been well studied in real-time fashion.

Methods

Tregs from naïve LEW rats were purified in two steps with the autoMACS system. Immunosuppression potential of these cells was examined with mixed lymphocyte reaction. Following stimulation by the alloantigen in vitro, the purified Tregs were infused into the recipients of vascularized composite allotransplantation (VCA). Secondary allogeneic skin grafting challenge was performed on the recipients with long-term survived VCA. Live optical imaging was performed to track luciferase-expressing Tregs following infusion to the VCA recipients. Expression of relevant molecules was studied by flow cytometry or quantitative RT-PCR.

Results

Rat Tregs were enriched following two-step cell sorting and showed immunosuppressive capacity. Upon infusion into the VCA recipients that have been treated with antilymphocyte serum and short-term Cyclosporin A, the antigen-stimulated Tregs significantly prolonged VCA survival and induced donor-specific tolerance. Tracking of the infused bioluminescent Tregs showed their specific homing to lymph nodes, and then to the VCAs. Following secondary skin grafting, Tregs specifically gathered at the donor-derived skin that was not rejected by the recipient. The in vivo migratory pattern coincided with the altered expression of cell surface molecules of CD62L, CD103, CD134, and CD278, following donor-antigen stimulation. Elevated expression of CCR4 and CCL22 in allograft may also participate in recruiting Tregs for maintenance of VCA survival and promoting donor-specific tolerance.

Conclusion

Sorted Tregs induced donor-specific tolerance to VCA in rats. Live cell tracking demonstrated that activated CD4⁺CD25⁺FoxP3⁺ Tregs targeted primarily to the lymph nodes and VCA. The Tregs migrated to the secondary grafted donor skin and contributed to the maintenance of donor-specific tolerance. These behaviors were associated with phenotypic changes induced by donor antigen stimulation. Increased expression of CCR4 and CCL22 in VCA skin may also be relevant.

Meta-analysis of 74,046 individuals identifies 11 new susceptibility loci for Alzheimer's disease

Eleven susceptibility loci for late-onset Alzheimer's disease (LOAD) were identified by previous studies; however, a large portion of the genetic risk for this disease remains unexplained. We conducted a large, two-stage meta-analysis of genome-wide association studies (GWAS) in individuals of European ancestry. In stage 1, we used genotyped and imputed data (7,055,881 SNPs) to perform meta-analysis on 4 previously published GWAS data sets consisting of 17,008 Alzheimer's disease cases and 37,154 controls. In stage 2, 11,632 SNPs were genotyped and tested for association in an independent set of 8,572 Alzheimer's disease cases and 11,312 controls. In addition to the APOE locus (encoding apolipoprotein E), 19 loci reached genome-wide significance (P < 5 × 10(-8)) in the combined stage 1 and stage 2 analysis, of which 11 are newly associated with Alzheimer's disease.

An 802.11 n wireless local area network transmission scheme for wireless telemedicine applications

In this paper, an 802.11 n transmission scheme is proposed for wireless telemedicine applications. IEEE 802.11n standards, a power assignment strategy, space-time block coding (STBC), and an object composition Petri net (OCPN) model are adopted. With the proposed wireless system, G.729 audio bit streams, Joint Photographic Experts Group 2000 (JPEG 2000) clinical images, and Moving Picture Experts Group 4 (MPEG-4) video bit streams achieve a transmission bit error rate (BER) of 10-7, 10-4, and 103 simultaneously. The proposed system meets the requirements prescribed for wireless telemedicine applications. An essential feature of this proposed transmission scheme is that clinical information that requires a high quality of service (QoS) is transmitted at a high power transmission rate with significant error protection. For maximizing resource utilization and minimizing the total transmission power, STBC and adaptive modulation techniques are used in the proposed 802.11 n wireless telemedicine system. Further, low power, direct mapping (DM), low-error protection scheme, and high-level modulation are adopted for messages that can tolerate a high BER. With the proposed transmission scheme, the required reliability of communication can be achieved. Our simulation results have shown that the proposed 802.11 n transmission scheme can be used for developing effective wireless telemedicine systems.

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.

Production, Purification, and Characterization of alpha-Galactosidase from Monascus pilosus

A Monascus pilosus strain was selected for production of intracellular alpha-galactosidase. Optimum conditions for mycelial growth and enzyme induction were determined. Galactose was one of the best enzyme inducers. The enzyme was purified by ammonium sulfate precipitation, gel filtration, and ion exchange chromatography and was demonstrated to be homogeneous by slab gel electrophoresis. The molecular weight of this enzyme, estimated by gel filtration, was about 150,000. The optimum conditions for the enzyme reaction was pH 4.5 to 5.0 at 55 degrees C. The purified enzyme was stable at 55 degrees C or below and in buffer at pH 3 to 8. The activity was inhibited by mercury, silver, and copper ions. The kinetics of this enzyme, with p-nitrophenyl-alpha-d-galactoside as substrate, was determined: K(m) was about 0.8 mM, and V(max) was 39 mumol/min per mg of protein. Enzymatic hydrolysis of melibiose, raffinose, and stachyose was analyzed by thin-layer chromatography.

Alpinia pricei Hayata rhizome extracts have suppressive and preventive potencies against hypercholesterolemia

The aim of this study was to investigate the effects of 70% ethanol extracts of Alpinia pricei (APE) on lipid profiles and lipid peroxidation. Syrian hamsters were fed a chow-based hypercholesterolemic diet (HCD) for 2 weeks to induce hypercholesterolemia (>250 mg/dl). To evaluate the potency of APE in suppressing hypercholesterolemia, hamsters were then fed HCD plus a high dose (500 mg/kg body weight) or a low dose (250 mg/kg body weight) of APE, or only HCD for another 4 weeks. We found that hypercholesterolemic hamsters fed a high dose of APE had lower serum total cholesterol (TC) and low-density lipoprotein-cholesterol (LDL-C) levels, lower thiobarbituric acid reactive substances (TBARS) and alanine aminotransferase (ALT) activities, lower atherogenic indices (LDL-C/HDL-C and TC/HDL-C ratios), and lower hepatic protein expression of peroxisome proliferators activated receptor gamma (PPARgamma) than hamsters fed a HCD diet. In addition, we also determined the preventive effects of APE on hamsters fed a HCD for 6 weeks. The hypocholesterolemic effects were also found in hamsters co-fed a high dose of APE and HCD for 6weeks. These results suggest that APE has both suppressive and preventive potencies against hypercholesterolemia and has the potency to protect against lipid peroxidation.

Differential effects of propofol and isoflurane on the activation of T-helper cells in lung cancer patients

It is suggested that activation and differentiation of T-helper cells are required for peri-operative anti-tumor and anti-infection immunity. The present study aimed to evaluate whether propofol stimulates the activation and differentiation of these cells in patients undergoing pulmonary lobectomy for non-small-cell lung cancer. Thirty patients were randomly allocated to receive propofol or isoflurane throughout surgery. The CD4(+)CD28(+) percentage (p < 0.0001) and the ratio of interferon-gamma:interleukin-4 (p = 0.001) all increased with propofol but showed no change with isoflurane. In contrast, cortisol increased with isoflurane (p < 0.0001) but not with propofol over time (p = 0.06). We conclude that propofol promotes activation and differentiation of peripheral T-helper cells.

Hydrogen-rich fuel gas from rice straw via microwave-induced pyrolysis

This study aimed to research the productivity of H(2)-rich fuel gas from rice straw using the microwave-induced pyrolysis. The formation constituents of gas product and the mechanism of its production were also discussed. The primary components of gas product were H(2), CO(2), CO, and CH(4), with average percentages of 50.67, 22.56, 16.09, and 7.42vol.%, respectively. According to the TA-MS analysis, it was suggested that focused heating by microwaves made the microwave-induced pyrolysis different from the traditional pyrolysis. A chemical equation could be nearly balanced to illustrate the gas composition generated from rice straw. From the viewpoint of energy consumption, close to 60% of the input energy could be derived and utilized as bioenergy.

White-light electroluminescence from ZnO nanorods/polyfluorene by solution-based growth

We report bright white-light electroluminescence (EL) from a diode structure consisting of a ZnO nanorod (NR) and a p-type conducting polymer of poly(fluorine) (PF) fabricated using a hydrothermal method. ZnO NRs are successfully grown on an organic layer of PF using a modified seeding layer. The EL spectrum shows a broad emission band covering the entire visible range from 400 to 800 nm. White-light emission is possible because the ZnO-defect-related emission from the ZnO NR/PF heterostructure is enhanced to become over thousand times stronger than that from the usual ZnO NR structure. This strong green-yellow emission associated with the ZnO defects, combined with the blue PF-related emission, results in the white-light emission. Enhancement of the ZnO-defect emission is caused by the presence of Zn(OH)(2) at the interface between the ZnO NRs and PF. Fourier transform infrared spectroscopy reveals that the absorption peaks at 3441, 3502, and 3574 cm(-1) corresponding to the OH group are formed at the ZnO NR/PF heterostructure, which confirms the enhancement of defect emission from the ZnO NR/PF heterostructure. The processing procedure revealed in this work is a convenient and low-cost way to fabricate ZnO-based white-light-emitting devices.

Inhibiting glycogen synthase kinase-3 reduces endotoxaemic acute renal failure by down-regulating inflammation and renal cell apoptosis

BACKGROUND AND PURPOSE

Excessive inflammation and apoptosis are pathological features of endotoxaemic acute renal failure. Activation of glycogen synthase kinase-3 (GSK-3) is involved in inflammation and apoptosis. We investigated the effects of inhibiting GSK-3 on lipopolysaccharide (LPS)-induced acute renal failure, nuclear factor-kappaB (NF-kappaB), inflammation and apoptosis.

EXPERIMENTAL APPROACH

The effects of inhibiting GSK-3 with inhibitors, including lithium chloride (LiCl) and 6-bromo-indirubin-3'-oxime (BIO), on LPS-treated (15 mg x kg(-1)) C3H/HeN mice (LiCl, 40 mg x kg(-1) and BIO, 2 mg x kg(-1)) and LPS-treated (1 microg x mL(-1)) renal epithelial cells (LiCl, 20 mM and BIO, 5 microM) were studied. Mouse survival was monitored and renal function was analysed by histological and serological examination. Cytokine and chemokine production, and cell apoptosis were measured by enzyme-linked immunosorbent assay and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling staining, respectively. Activation of NF-kappaB and GSK-3 was determined by immunostaining and Western blotting, respectively.

KEY RESULTS

Mice treated with GSK-3 inhibitors showed decreased mortality, renal tubular dilatation, vacuolization and sloughing, blood urea nitrogen, creatinine and renal cell apoptosis in response to endotoxaemia. Inhibiting GSK-3 reduced LPS-induced tumour necrosis factor-alpha (TNF-alpha) and CCL5/RANTES (released upon activation of normal T-cells) in vivo in mice and in vitro in murine kidney cortical collecting duct epithelial M1 cells. Inhibiting GSK-3 did not block TNF-alpha-induced cytotoxicity in rat kidney proximal tubular epithelial NRK52E or in M1 cells.

CONCLUSIONS AND IMPLICATIONS

These results suggest that GSK-3 inhibition protects against endotoxaemic acute renal failure mainly by down-regulating pro-inflammatory TNF-alpha and RANTES.

Total recovery of resources and energy from rice straw using microwave-induced pyrolysis

This article presents the application of microwave-induced pyrolysis to total recovery of resources and energy from rice straw. The microwave power and particle size of feedstock were both key parameters affecting the performance of microwave-induced pyrolysis. Under 400-500W microwave power, the reduction of fixed carbon in the biomass was significant. From the experimental results of specific surface area, zeta potential, and Cu2+ adsorption, the applications of solid residues in the water and wastewater treatment could be expected. The major compositions in gaseous product were H2, CO2, CO, CH4 of 55, 17, 13, 10vol.%, respectively. The high H2 content might imply that microwave-induced pyrolysis of biomass waste has the potential to produce the H2-rich fuel gas. Alkanes, polars, and low-ringed polycyclic aromatic hydrocarbons were three primary kinds of compounds in the liquid product.

The removal and recovery of Cr(VI) by Li/Al layered double hydroxide (LDH)

Hexavalent Cr has been identified as one of the toxic metals commonly present in industrial effluents. Among the treatment techniques developed for removing Cr(VI) from waste waters, sorption is most commonly applied, due to its simplicity and efficiency. However, few adsorbents can be recycled and reused cost-effectively. In this study, the removal and recovery of Cr(VI) from water using Li/Al LDH was investigated. The removal of Cr(VI) by Li/Al LDH was evaluated in a batch mode. The results demonstrated that Cr(VI) adsorption onto Li/Al LDH occurs by replacing the Cl(-) that originally exists in the interlayer of the adsorbent. The degree of Cr(VI) adsorption observed for Li/Al LDH was relatively high and the process occurred rapidly; however, a portion of adsorbed Cr(VI) was gradually desorbed, due to the Li de-intercalation of Li/Al LDH. Lithium de-intercalation from Li/Al LDH with interlayer Cl(-) and interlayer Cr(VI) follows the first order kinetics and has the activation energies of 76.6 and 41.5 kJ mol(-1), respectively. The properties of thermal unstability and the high adsorption capacity of Li/Al LDH may lead to the development of an innovative technique for the removal of Cr(VI) from Cr(VI)-containing wastewater. That is, Li/Al LDH may be used as an effective adsorbent for the adsorption of Cr(VI) in an ambient environment. Following the adsorptive process, the adsorbed Cr(VI) may be released, using heated water to treat the Cr(VI)-containing Li/Al LDH particles. Through this hydrothermal treatment of the used adsorbent, Cr(VI) can be recovered and the solid product (gibbsite) can be recycled for further use.

Ceramide in apoptotic signaling and anticancer therapy

Ceramide, a product of sphingolipid metabolism, is generated in response to various stress stimuli, such as tumor necrosis factor-alpha, CD95/Fas, chemotherapeutic agents, and irradiation. Ceramide may modulate the biochemical and cellular processes that lead to apoptosis. However, the mechanisms by which ceramide regulates apoptotic events are not fully defined. It is believed that the biological effect of ceramide depends on its concentration, the activation or differentiation status of the cell, and the time frame of action. Here, we discuss the metabolism and cell apoptotic signaling of ceramide. The involvement of protein kinases (i.e. PI3K/Akt and GSK-3beta) and protein phosphatases (i.e. PP1 and PP2A), Bcl-2 family proteins, mitochondrial damage, and caspase cascade activation are demonstrated. Further, ceramide and its derivatives have recently been incorporated into strategies for anticancer therapies. An understanding of the apoptotic signaling pathways mediated by ceramide may shed light on its potential for therapeutic intervention.

Antibody to severe acute respiratory syndrome (SARS)-associated coronavirus spike protein domain 2 cross-reacts with lung epithelial cells and causes cytotoxicity

Both viral effect and immune-mediated mechanism are involved in the pathogenesis of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) infection. In this study, we showed that in SARS patient sera there were autoantibodies (autoAbs) that reacted with A549 cells, the type-2 pneumocytes, and that these autoAbs were mainly IgG. The autoAbs were detectable 20 days after fever onset. Tests of non-SARS-pneumonia patients did not show the same autoAb production as in SARS patients. After sera IgG bound to A549 cells, cytotoxicity was induced. Cell cytotoxicity and the anti-epithelial cell IgG level were positively correlated. Preabsorption and binding assays indicated the existence of cross-reactive epitopes on SARS-CoV spike protein domain 2 (S2). Furthermore, treatment of A549 cells with anti-S2 Abs and IFN-gamma resulted in an increase in the adherence of human peripheral blood mononuclear cells to these epithelial cells. Taken together, we have demonstrated that the anti-S2 Abs in SARS patient sera cause cytotoxic injury as well as enhance immune cell adhesion to epithelial cells. The onset of autoimmune responses in SARS-CoV infection may be implicated in SARS pathogenesis.

Pycnogenol induces differentiation and apoptosis in human promyeloid leukemia HL-60 cells

Pycnogenol, rich of many phytochemicals of medical value, is a commercialized nutrient supplement extracted from the bark of European coastal pine. In this study, we investigated the anti-tumor effects of Pycnogenol on HL-60, U937 and K562 human leukemia cell lines. We found that Pycnogenol inhibited cell proliferation dose- and time-dependently, and the IC(50)s of Pycnogenol on HL-60, U937 and K562 cells were 150, 40 and 100 microg/ml, respectively. When HL-60 cells were incubated with low concentrations of Pycnogenol (50, 100 and 125 microg/ml) for 24 h, a prominent G0/G1 arrest was observed, followed by gradual accumulation of sub-G0/G1 nuclei. At 48 h of treatment, 50-70% of HL-60 cells differentiated, as evidenced by morphological changes, NBT reduction, induction of NSE activity, and increases of cell surface expression of CD11b. However, results from Annexin V/PI staining, DAPI staining and DNA fragmentation assay indicated that Pycnogenol induced HL-60, U937 and K562 cell apoptosis at their respective IC(50)s after 24 h of treatments. Pretreatment of z-DEVD-fmk, a caspase-3 specific inhibitor, not only decreased caspase-3 activity but also reduced the percentage of apoptotic cells induced by Pycnogenol. This indicated that caspase-3 activation was involved in Pycnogenol induced-apoptosis. In conclusion, Pycnogenol induced differentiation and apoptosis in leukemia cells. Our data suggest that Pycnogenol could serve as a potent cancer chemopreventive or chemotherapeutic agent for human leukemia.

Antibody-mediated endothelial cell damage via nitric oxide

Vascular disorders, resulting from endothelial cell dysfunction, may be caused by various stimuli, including infectious pathogens, cytotoxic reagents, and pathophysiological mechanisms mediated by immune responses. Endothelial cell dysfunction characterized by apoptosis and abnormal immune activation is, at least in part, induced by anti-endothelial cell antibody (AECA) in some cases of autoimmune disease. However, the molecular mechanisms of AECA-mediated pathogenetic damage to host vascular system remain unclear. The dual role of nitric oxide (NO) both in endothelial cell apoptosis and survival has been described. In this paper, endothelial cell apoptosis caused by the presence of cross-reactive AECA via a NO-mediated mechanism is demonstrated in dengue virus infection. Endothelial cells undergo apoptosis via the mitochondria-dependent pathway that is regulated by NO production. NO-regulated endothelial cell injury thus may play a role in the disruption of vessel endothelium and contribute to the AECA-induced pathogenesis of vasculopathy. The modulation of NO may provide the therapeutic strategies for autoimmune diseases by preventing the AECA-mediated endothelial cell damage.

Motorcycle emissions and fuel consumption in urban and rural driving conditions

This work reports sampling of motorcycle on-road driving cycles in actual urban and rural environments and the development of representative driving cycles using the principle of least total variance in individual regions. Based on the representative driving cycles in individual regions, emission factors for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO(x)=NO+NO(2)) and carbon dioxide (CO(2)), as well as fuel consumption, were determined using a chassis dynamometer. The measurement results show that the representative driving cycles are almost identical in the three largest cities in Taiwan, but they differ significantly from the rural driving cycle. Irrespective of driving conditions, emission factors differ insignificantly between the urban and rural regions at a 95% confidence level. However, the fuel consumption in urban centers is approximately 30% higher than in the rural regions, with driving conditions in the former usually poor compared to the latter. Two-stroke motorcycles generally have considerably higher HC emissions and quite lower NO(x) emissions than those of four-stroke motorcycles. Comparisons with other studies suggest that factors such as road characteristics, traffic volume, vehicle type, driving conditions and driver behavior may affect motorcycle emission levels in real traffic situations.

Arterial blood pressure and blood lipids as cardiovascular risk factors and occupational stress in Taiwan

BACKGROUND

This study is to determine whether occupational stress (defined as high psychological demands and low decision latitude on the job) is associated with increased blood pressure and abnormal level of blood lipids as cardiovascular risk factors.

METHODS

We conducted a cross-sectional study at three work sites of 526 white-collar male workers aged 20 to 66 years without evidence of cardiovascular disease. Systolic, diastolic blood pressure, serum total, high-density lipoprotein cholesterol and plasma triglyceride were measured. Occupational stress index was derived from data collected in the job strain questionnaire.

RESULTS

In multiple linear regression models, occupational stress index was significantly related to diastolic blood pressure and plasma triglyceride, after adjusting for age, education, smoking, and alcohol consumption. A higher occupational stress index was directly associated with higher systolic, diastolic blood pressure and higher level of plasma triglyceride.

CONCLUSIONS

These data from a white-collar working population confirm independent relations between occupational stress defined in the job demand-control model and diastolic blood pressure observed in predominantly Western populations and extend the range of associations to plasma triglyceride than do previous studies.

Effect of elbow flexion on upper extremity impact forces during a fall

OBJECTIVE

The overall objectives are to develop a biomechanical model for a simulated fall with outstretched hand.

DESIGN

Cross-sectional study involving young healthy volunteers in a university research laboratory setting.

BACKGROUND

Little is known about the factors which influence fracture risk during a fall on outstretched hand.

METHODS

A group of 11 male subjects volunteered for this investigation. A set of eight reflective markers was placed bilaterally on selected anatomic landmarks. Subjects were suspended with both elbows extended and wrists dorsiflexed, preparing to impact the ground and force plates from two different fall heights: 3 and 6 cm. Two different postures for the elbows were employed. In the elbow extension experiment, the elbows were extended at all times. In the elbow flexion experiment, the elbows were extended at impact, but then flexed immediately, as though in the initial downward phase of a push-up exercise.

RESULT

Increasing the fall height significantly increased the upper extremity axial forces by 10% and 5%. No significantly different differences were found in the axial forces applied to the wrist, elbow or shoulder between the elbow flexion and elbow extension trials, but the elbow mediolateral shear force was 68% larger (P=0.002) in the extension trials.

CONCLUSIONS

Performing an elbow flexion movement at impact reduces the first peak impact force value and postpones the maximum peak value. Although changing the fall arrest strategy from elbow extension to elbow flexion did not affect the peak impact force on the hand, it did require substantially greater elbow and shoulder muscle strengths.

RELEVANCE

This paper yields insights into how the physical demands of arresting mild falls may relate to upper extremity muscle capacity, joint dislocation and bony fracture.

Sequence influence of nonidentical InGaAsP quantum wells on broadband characteristics of semiconductor optical amplifiers--superluminescent diodes

Extremely broadband emission is obtained from semiconductor optical amplifiers-superluminescent diodes with nonidentical quantum wells made of InGaAsP/InP materials. The well sequence is experimentally shown to have a significant influence on the emission spectra. With the three In(0.67) Ga(0.33) As(0.72) P(0.28) quantum wells near the n -cladding layer and the two In(0.53) Ga(0.47) As quantum wells near the p -cladding layer, all bounded by In(0.86) Ga(0.14) As(0.3)P(0.7) barriers, the emission spectrum could cover from less than 1.3 to nearly 1.55 microm, and the FWHM could be near 300 nm.

Intertrochanteric fractures in adults younger than 40 years of age

This study reviewed 66 intertrochanteric fractures in patients younger than 40 years old (average 33.0 years old; range 17-40 years old). In contrast to the usual population with intertrochanteric fractures, the factors male predominance (46/66), less pre-injury comorbidity (9/66), more outdoor high energy trauma (47/66), and more associated injuries (32/66) were evident. The distribution of associated injuries was wide. Some of them were life threatening. According to Boyd's classification, 20 were type I, 24 were type II, 13 were type III, and 9 were type IV. Twenty-nine were stable, and 37 were unstable. Stratified by the mechanism of injury, the difference in distribution between the subgroups was significant (p = 0.027, two-tail Fisher's exact test). Simple falls only caused Boyd type I and II fractures. Boyd type III or IV fractures were found more often after vehicular trauma or falls from a height. All the intertrochanteric fractures healed on average 70.5 days (range 31-213 days) after operation. The fractures resulting from vehicular trauma or fall from a height healed significantly more slowly (p = 0.02, univariant log-rank test). There were 6 intertrochanteric fracture-related complications. The mechanism of injury determines the character of intertrochanteric fractures in young adults. Given tougher bone stock, better healing ability, and less co-morbidity, proper management can lead to healing of all intertrochanteric fractures. The extent of functional recovery was also determined by the associated injuries.

Cefuroxime-impregnated cement at primary total knee arthroplasty in diabetes mellitus. A prospective, randomised study

We have performed a prospective single-blinded randomised study to evaluate the role of antibiotic-impregnated cement in the prevention of deep infection at primary total knee arthroplasty (TKA) in patients with diabetes mellitus. We studied prospectively 78 arthroplasties performed for osteoarthritis in such patients. They were randomly separated into two groups. In group 1 (41 knees), cefuroxime-impregnated cement was used while in group 2 (37 knees) cefuroxime was not added to the cement. The preoperative, intraoperative and postoperative management was the same for both groups. The mean follow-up was 50 months (26 to 88). There were no cases of deep infection in group 1, but five (13.5%) occurred in group 2 (p = 0.021). We conclude that cefuroxime-impregnated cement is effective in the prevention of deep infection at primary TKA in patients with diabetes mellitus.

Characterization of the replication region of the Lactobacillus reuteri plasmid pTC82 potentially used in the construction of cloning vector

A 3.2 kb DNA fragment containing the replication region (RR) from pTC82 was cloned, sequenced, and found to contain elements typical of plasmids that replicate via a rolling-circle mechanism of replication (RCR), including double-strand origin (DSO), replication protein gene (rep), and single-strand origin (SSO). The DSO of pTC82 contains two domains showing 55.5% and 84.6% similarities in nucleotide (nt) sequence to the conserved functional elements bind and nic, respectively, which are required for the initiation of the leading strand typical of the pC194-RCR family. Although the predicted rep gene product of pTC82 (Rep82) shares little identity (less than 24%) with other known Reps, a region containing three motifs, characteristic of the pC194-family Reps, was identified, indicating the Rep82 as a novel Rep protein of this family. Downstream of the rep82 gene, strong similarity to the typical palT type-SSO could be detected. This is the first palT type-SSO to be identified from Lactobacillus. Through a series of deletion studies, the minimal replicon of the cloned RR was found to be 2.66 kb in size including the DSO region and rep gene. This RR was further identified as being highly stable in L. reuteri and also bearing a very narrow host-range property, suggesting it to be a good replicon potentially useful in vector construction for developing L. reuteri as a vaccine carrier.

A series of enediynes as novel inhibitors of topoisomerase I

A series of acyclic enediynes, 2-((6-substituted)-3-hexen-1,5-diynyl)benzonitriles (8--11), display potent inhibition against topoisomerase I without the formation of active biradical intermediates and show inhibitory activity against topoisomerase I at 10 microM, which is five times that of camptothecin from the results of agarose gel electrophoresis.

Effect of functional groups of humic substances on uf performance

The role of different functional groups present in humic substances on the membrane flux is unclear. This study is undertaken to (1) separate the carboxyl and phenolic groups from a humic solution, and (2) evaluate the effect of each fractionated humic substances on the ultrafiltration (UF) performance. A weak-base amine resin was used for the adsorption (pH 7) and the subsequent desorption (pH 13) of the phenolic groups from a commercial humic solution. These fractions were evaluated qualitatively (via Fourier transform infrared spectroscopy) and quantitatively (titration); they were further subjected to the analyses of the trihalomethane formation potential (THMFP) and ultrafiltration performance. Although, a complete separation of the phenolic and carboxyl groups is not possible, the results nevertheless provide useful information about their effects on UF performance. The fraction with a higher content of the phenolic OH group exhibits the highest THMFP (190 microg/mg C), whereas the fraction with a higher content of the carboxyl groups exhibits more flux decline. The UF system evaluated is unable to remove a significant portion of THM precursors, resulting in high THMs in permeate. The use of powdered activated carbon for the pretreatment of these fractions fails to improve membrane fouling. The pore size of UF membrane does not appear to affect the membrane flux, and the switch from the hydrophobic to hydrophilic membrane only slight improves the permeate flux.

Determination of source contributions to ambient PM2.5 in Kaohsiung, Taiwan, using a receptor model

Ambient particulates of PM2.5 were sampled at three sites in Kaohsiung, Taiwan, during February and March 1999. In addition, resuspended PM2.5 collected from traffic tunnels, paved roads, fly ash of a municipal solid waste (MSW) incinerator, and seawater was obtained. All the samples were analyzed for twenty constituents, including water-soluble ions, organic carbon (OC), elemental carbon (EC), and metallic elements. In conjunction with local source profiles and the source profiles in the model library SPECIATE EPA, the receptor model based on chemical mass balance (CMB) was then applied to determine the source contributions to ambient PM2.5. The mean concentration of ambient PM2.5 was 42.69-53.68 micrograms/m3 for the sampling period. The abundant species in ambient PM2.5 in the mass fraction for three sites were OC (12.7-14.2%), SO4(2-) (12.8-15.1%), NO3- (8.1-10.3%), NH4+ (6.7-7.5%), and EC (5.3-8.5%). Results of CMB modeling show that major pollution sources for ambient PM2.5 are traffic exhaust (18-54%), secondary aerosols (30-41% from SO4(2-) and NO3-), and outdoor burning of agriculture wastes (13-17%).

Generation of IgM anti-platelet autoantibody in dengue patients

Dengue virus infection causes a wide range of diseases from dengue fever to life-threatening dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS). The mechanisms involved in DHF/DSS pathogenesis remain unclear. Patient sera collected from an outbreak in southern Taiwan from November 1998 to January 1999 were studied. The presence of antibodies which cross-reacted with platelets could be detected in patient sera, and the isotype of these autoantibodies was IgM. The anti-platelet IgM levels were higher in DHF/DSS than in dengue fever patient sera in disease acute phase. These autoantibodies were still detectable in convalescent stage (1-3 weeks after acute phase) and even eight to nine months after illness. The platelet binding activity was not observed in other virus-infected patient sera tested. Further investigation showed that dengue patient sera caused platelet lysis in the presence of complement. The platelet cytotoxicity induced by DHF/DSS patient sera was higher than that by dengue fever sera. Dengue patient sera also inhibited platelet aggregation which, however, appeared to be not related to DHF/DSS development.

Modeling Competitive Adsorption of Molybdate, Sulfate, and Selenate on gamma-Al(2)O(3) by the Triple-Layer Model

Competitive adsorption of molybdate, sulfate, and selenate onto gamma-Al(2)O(3) was investigated in the present study. Binary solute systems of MoO(2-)(4)+SO(2-)(4), MoO(2-)(4)+SeO(2-)(4), and SO(2-)(4)+SeO(2-)(4) and a ternary solute system of MoO(2-)(4)+SO(2-)(4)+SeO(2-)(4) were evaluated to determine their relative effects on competitive adsorption on the gamma-Al(2)O(3) surface. Anionic competitive adsorption efficiency was pH dependent. The higher the pH, the lower the efficiency of MoO(2-)(4) in preventing SO(2-)(4) and SeO(2-)(4) adsorption; similar results were found in SeO(2-)(4) depressing SO(2-)(4) adsorption. This research found that more sites are occupied in mixed anionic adsorbate systems than when either ion is present alone. The results suggest that the gamma-Al(2)O(3) surface is composed of many groups of binding sites. Because of the heterogeneity of adsorption sites, the triple-layer model (TLM) predicted the competitive effects qualitatively but not quantitatively. TLM gave reasonable descriptions of molybdate adsorption in the presence of sulfate and selenate, indicating that the model may be useful in predicting molybdate adsorption on gamma-Al(2)O(3). Copyright 2001 Academic Press.

Sludge dewatering using centrifuge with thermal/polymer conditioning

Sludge dewatering is preceded by a conditioning operation to enhance water removal efficiency. In the conditioning operation, chemical coagulants or polymers are added to promote sludge particle aggregation for easier dewatering. In this study, an alternative conditioning method for sludge thermal treatment at temperatures up to 80 degrees C was extensively investigated. Dewatering characteristics such as sludge capillary suction time and specific resistance to filtration, sludge viscosity and concentration of solid cakes were examined thoroughly. A good correlation between capillary suction time and specific resistance to filtration was established for sludges from water treatment, but not for biological sludge. Cationic polymer exhibits the best enhancement on sludge moisture removal. The sludge rheogram varies from 60 to 5 cP as temperature changes from 20 to 80 degrees C for sludges from water treatment plant. The dewatering ability of sludge can be greatly enhanced by thermal treatment in conjunction with the use of polymers.

Surgical treatment of full thickness rotator cuff tear in patients younger than 40 years

BACKGROUND

Full thickness tear of the rotator cuff is a well-known entity in the middle-aged and elderly population and the results of surgical repair are well documented. Rotator cuff tear in patients under the age of 40 years is unusual and the cause and treatment are not well established. The present study reports 12 young patients with full thickness tear of the rotator cuff treated surgically.

METHODS

Open anteroinferior acromioplasty and cuff repairs were performed on every patient after failure of nonsurgical treatment. The average follow-up was 59.5 months (range, 36-100 months).

RESULTS

The average patient age at the time of surgery was 30.2 years (range, 17-39 years). Symptoms included pain and dysfunction in all patients and weakness in eight patients. The duration of symptoms before surgery ranged from 6 to 60 months (average, 22.8 months). Ten patients were able to return to their preinjury status within an average of 4.5 months (range, 3-9 months) after surgery. Three athletes were able to return to previous levels of competition. Nine patients had excellent functional results with regard to pain, motion, strength, function and satisfaction. Eleven patients were satisfied with the operation and had significant pain reduction compared with their preoperative status.

CONCLUSIONS

An acute traumatic event was the etiology of the rotator cuff tears in this study. The results of surgical treatment in this younger group of patients were satisfactory and were comparable to the outcomes reported for surgical treatment of rotator cuff tears in older patients and athletes.

Purification and properties of ornithine racemase from Clostridium sticklandii

Ornithine racemase has been purified to homogeneity from Clostridium sticklandii, as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This is the first racemase known to be highly specific to ornithine. This PLP-dependent enzyme has an M(r) of 92, 000, with a K(m) for L-ornithine of 0.77 +/- 0.05 mM and a k(cat) of 980 +/- 20 s(-1).

Growth, pigment production and protease activity of Monascus purpureus as affected by salt, sodium nitrite, polyphosphate and various sugars

The effect of different levels of salt, sodium nitrite, polyphosphate and various sugars on growth, pigment production, protease activity and culture pH caused by Monascus purpureus was studied in broth medium and ground meat. The addition of sodium chloride (> 50.0 g l(-1)) and polyphosphate (> 3.0g l(-1)) to broth medium decreased mycelial growth, pigment production and protease activity of M. purpureus, whereas low concentrations of sodium nitrite (< 0.2 g l(-1)) promoted mycelial growth and pigment production. When the basal medium and ground meat contained salt, 150.0 g l(-1), the mould growth was stopped. The medium with fructose as carbon source proved to be the most suitable for mycelium growth and pigment production, with maltose and glucose being the second most productive. When sucrose and lactose were used as carbon sources, mycelium growth and pigment production were inhibited but the protease activity increased significantly. The mould showed more tolerance to salt and polyphosphate in ground meat than in broth medium and used sucrose as a carbon source as well as glucose for growth and pigment production in the meat mixture.

Use of alternative therapy among pediatric oncology patients in Taiwan

Both alternative medicine and western medicine have been commonly used to treat pediatric cancer patients in Taiwan. Each has its own intrinsic strengths and weaknesses and they can be complementary. Little is known about medical help-seeking behaviors of parents of pediatric cancer patients, especially those related to alternative therapies. This study investigated the extent and parental expectations on use of alternative therapies. All primary caregivers of 63 eligible patients were interviewed. Use of alternative therapies, regardless of education level or social status of their families, is prevalent (n = 46, 73%) in Taiwan. Commonly used alternative therapies included, in order of popularity, formulated functional food (n = 22, 48%), temple worship/shamanism (n = 19, 40%), traditional Chinese medicine (n = 9, 20%), secret recipes/herbs (n = 13, 28%), and diet supplements (n = 9, 19%). Such practices generally occur without medical guidance from oncologists, largely because of poor interactions between parents and oncologists. Future efforts should be made to encourage both parents and oncologists to discuss this issue. Nurses may serve as mediators by developing mutual trust and a sharing relationship between these groups.

Double Anionic Cycloaromatization of 2-(6-Substituted-3-hexene-1,5-diynyl)benzonitriles Initiated by Methoxide Addition

[reaction: see text] Treatment of 2-((3Z)-undecene-1,5-diynyl)benzonitrile with 5 equiv of sodium methoxide in refluxing methanol for 16 h gave 1-pentyl-6-methoxyphenanthridine in 12% yield, 1-pentyl-6-phenanthridone in 6% yield, and 2-(2-pentyl-6-methoxyphenyl)benzonitrile in 4% yield. Under the same reaction conditions, methanolysis of several other benzonitriles gave similar results. Phenanthridine and biphenyl derivatives were obtained as the major products. A mechanism for this novel cycloaromatization reaction of enediynes is proposed.

Cloning of erythromycin-resistance determinants and replication origins from indigenous plasmids of Lactobacillus reuteri for potential use in construction of cloning vectors

Lactobacillus reuteri L1 and N16 strains contain a 7.0-kb plasmid (pTE80) and a 15-kb plasmid (pTE15), respectively, encoding resistance to erythromycin (Em(r)). Physical maps of both plasmids were established. Nucleotide sequences of the genetic determinants encoding Em(r) on pTE80 and pTE15 revealed the existence of a very similar (ca. 99% nucleotide sequence and ca. 98% amino acid sequence identity) open reading frame for an Em(r) transmethylase gene (erm) in both plasmids. These structural erm genes, 753 and 750 bp in length, respectively, were highly related (ca. 98% nucleotide sequence and ca. 97% amino acid sequence identity) to the erm gene of L. fermentum plasmid pLEM3. Sequence analysis showed that these two erm genes from pTE80 and pTE15 could be categorized under the ermB (ermAM) class. These are the first members of the ermB (ermAM) class of Em(r) determinant from L. reuteri to be characterized at the nucleotide sequence level. The Em(r) gene from pTE80 (erm80) was then ligated into pUC18/19 to construct replication origin (RO)-screening vectors pUE80(+) and pUE80(-) (pUE80(+/-)). These plasmids contain the pUC18/19-derived multiple cloning site, ampicillin-resistance trait, and the LacZ' gene, which enable direct screening for recombinants in Escherichia coli. Once the recombinant contains a RO from L. reuteri, the Em(r) trait of erm80 is used as a selection marker for the replication of the chimeric plasmid as it is transformed into L. reuteri using the cloned RO as a replicon. Replication regions from pTE80 and pTE15 were successfully cloned into the constructed vector pUE80(-). The RO cloned from pTE80 was further identified as being highly stable in L. reuteri and also bearing a relatively narrow host range compared with that of pTE15. The Em(r) determinant (erm80) and RO cloned from pTE80 could be used in the future construction of derivatives of cloning vectors for this microbe. Moreover, the pUE80(+/-) and pTE80-RO constructed in this study have the potential to be developed as a suicide vector and an E. coli-L. reuteri shuttle vector, respectively.

Determinants of parental decisions on 'drop out' from cancer treatment for childhood cancer patients

Little is known about the psychosocial process of parental decisions on 'drop out' from cancer treatment for paediatric patients in Taiwan. This study, based on structured in-depth interviews, attempted to document the determinants of parental decisions on drop out. A total of 19 parents of paediatric cancer patients who dropped out from a cancer treatment for at least a month within 3 years since first treatment were interviewed. Content analysis of qualitative data revealed six categories of determinants associated with parental decisions: suffering severe pain from medical treatments and adverse side-effects; desire for better and less painful treatments; adverse effect of other patients' experiences; searching for possible explanations for disease after prolonged denial of diagnosis; lack of empathy from health care professionals; and misinterpretation of improved prognostics. These findings reflected the deficiency of psychological and emotional support for parents from health care professionals prior to and during cancer treatment.

Requirement of I-E molecule for thymocyte apoptosis induced by staphylococcal enterotoxin B in vivo

In vivo administration of bacterial superantigen staphylococcal enterotoxin B (SEB) to BALB/c mice led to thymus atrophy resulting from thymocyte apoptosis. In this study, we demonstrated that SEB induced a substantial reduction in thymocyte numbers in BALB/c, B10. D2 (H-2(d) haplotype), B10.BR, C3H/HeJ, C3H/HeN (H-2(k)), and (BALB/c x B6)F1 (H-2(dxb)), but caused little or no effect in I-E- strains such as B6, B10, A.BY (H-2(b)), and A.SW (H-2(s)) mice. Elimination of CD4(+)CD8(+) cells predominantly accounted for the thymocyte loss, although the numbers of other subpopulations may also be reduced. Thymocyte apoptosis was shown by an increase in the level of DNA fragmentation in BALB/c but not in B6 mice after SEB administration. Treatment with anti-I-Ed monoclonal antibody to BALB/c mice blocked SEB-induced thymocyte apoptosis when anti-I-Ad exerted less effect. In contrast to SEB, staphylococcal enterotoxin A led to comparable levels of thymus atrophy in BALB/c and B6 mice. Studies on the surface marker expression indicated that CD25 expression was upregulated on BALB/c mouse thymocytes but with only a moderate increase in B6 mice. The CD4(+)CD8(+) cells were the major (>90%) population that expressed elevated levels of CD25 in BALB/c mice. An increase in the expression of TCRalphabeta, CD3, and CD69 surface markers was also observed on thymocytes from BALB/c mice, but not from I-E- strains. The differential response of I-E+ and I-E- mice to SEB may be exploited as a model for the study of apoptosis in the thymus.

Percutaneous A1 pulley release for trigger digits

BACKGROUND

Recently, percutaneous trigger digit release has been reported as a safe, effective office procedure. The purpose of this study was to further assess the safety and efficacy of this technique.

METHODS

From November, 1996, to August, 1997, 69 consecutive patients with 71 primary trigger digits were treated with percutaneous A1 pulley release. The operations were performed using the tip of a 19-gauge needle, mounted on a 3-ml syringe. The mean age of the patients was 66 years. The mean duration of follow-up was 21 weeks. The patients were prospectively classified into two groups according to age, sex, digit involved, duration of symptoms and whether or not they had had previous local steroid injection.

RESULTS

Sixty-three digits were completely free of triggering. Residual triggering or inadequate release was found in eight digits at final follow-up. The success rate was not associated with sex, age, digit involved, duration of symptoms or history of local steroid injection. No major complications were found in this study, but minor complications included persistent local tenderness in nine digits and subcutaneous hematoma in six digits. Risk factors related to persistent local tenderness were female gender and trigger thumb.

CONCLUSIONS

Percutaneous A1 pulley release is an effective, safe and convenient procedure for the treatment of trigger digits.

Adsorption/Desorption Kinetics of MoO2-4 onto gamma-Al2O3 by the Pressure-Jump Technique

The kinetics and mechanisms of molybdate adsorption/desorption at the gamma-Al2O3/water interface were studied by using the pressure-jump apparatus with conductivity detection at 298 K. A double relaxation was observed due to the adsorption/desorption process. Adsorption data and triple-layer model (TLM) simulation results suggest the formation of both mono- and bidentate inner-sphere complexes (SMoO-4 and S2MoO4) at the gamma-Al2O3 surface. The intrinsic equilibrium constants (Kinteq) of the complexes were 10(6.5) M-2 and 10(16) M-4, respectively. Based on the relaxation theory and combined results of TLM simulation, a two-step process is proposed. The first step (k1, k-1) is the formation of an ion-pair complex through the electrostatic attraction between the reacting surface sites and MoO2-4 and H+. The second step (k2, k-2) involves a ligand exchange process, whereby one water molecule is replaced by one adsorbed MoO2-4 from the surface. The values of adsorption and desorption rate constants in the MoO2-4/gamma-Al2O3 system were determined to be kint1 = 5.23 x 10(6) M-2 s-1, kint-1 = 2.41 x 10 s-1, kint-2 = 1.74 s-1, and kint-2 = 3.26 x 10(-1) s-1. The intrinsic equilibrium constant from kinetic measurements (Kintkin) was 10(6) M-2, which was similar to the intrinsic equilibrium constant (Kinteq), 10(6.5) M-2, from the equilibrium studies. Copyright 1998 Academic Press.

Computerized tomography in the diagnosis of subluxation of the distal radioulnar joint

BACKGROUND

The diagnosis of distal radioulnar joint (DRUJ) subluxation is difficult. Routine radiographs are imprecise in clinical analysis. However, the anatomy and dynamic configuration of this articulation have been clearly defined utilizing computerized tomography (CT). Three CT criteria for the evaluation of DRUJ subluxation have been reported: Mino's criteria, the epicenter method and the congruity method. Previous reports discussed these criteria in the analysis of symptomatic DRUJ, but no clear conclusion has been reached. The purpose of this study is to investigate accurate criteria of CT in defining subluxation of the DRUJ.

METHODS

Eighty distal radioulnar joints in 40 patients with suspected DRUJ subluxation underwent CT scans of both symptomatic and asymptomatic wrists. The CT scan was obtained through the DRUJ with the forearm in neutral rotation, active full supination and active full pronation. Three CT criteria were used to assess the DRUJ in all positions of unstable and normal wrists.

RESULTS

Overall, 54 wrists were included in the final analysis. Seventeen symptomatic wrists had frank DRUJ instability diagnosed from true lateral radiographs, and 11 were reconfirmed from intraoperative pathology. The other 37 wrists had normal DRUJ. Among the three methods, the epicenter method had similar sensitivity to Mino's criteria and the congruity method. However, the epicenter method had much better specificity than Mino's criteria and the congruity method.

CONCLUSIONS

For accurate diagnosis of subluxation of the DRUJ, CT scan through the symptomatic DRUJ in neutral rotation, active full supination, active full pronation and analysis with the epicenter method are recommended.

[Seroepidemiology of Toxoplasma gondii infection among Atayal aborigines and local animals in Nan-ao district, Ilan county and Jen-ai district, Nan-tou county, Taiwan]

In this study, latex agglutination test (LAT) was used to detect sera anti-toxoplasma antibodies of Atayal aborigines and local animals in Nan-ao district, Ilan county and Jen-ai district, Nan-tou county as a measure of exposure to the Toxoplasma gondii. Out of 422 Atayal aborigines and 64 different animals were tested in Nan-ao district and 82 Atayal children in Jen-ai district were also screened, the positive rates for sera anti-toxoplasma antibodies were 21.8%, 17.2% and 15.9%, respectively. In Nan-ao district, neither were the positive rates significantly different in males (22.1%) and females (21.4%), nor in humans (21.8%) and dogs (19.6%) (P > 0.05). The seroprevalence in adults (28.3%) was significantly higher than that in children (18.7%) (P < 0.05), and the highest seropositive rate (38.1%) was in the age group 50-59 years and the lowest (7.7%) was in the age group 1-9 years. In general, the age pattern of prevalence is consistent with increasing duration of exposure to Toxoplasma gondii with age. For animals, the seropositive rate in dogs (19.6%) was also significantly higher than that in wild rats (7.7%) (P < 0.05). No significant difference in seropositive rate of Atayal children was observed between Nan-ao and Jen-ai districts (P > 0.05).

Seroprevalence of Toxoplasma gondii antibodies among Atayal aboriginal people and their hunting dogs in northeastern Taiwan

Atayal aborigines, living at an altitude of 1,500-1,600 m in northeastern Taiwan, still hunt for wild animals with the help of hunting dogs. In this study, the latex agglutination test (LAT) was used to detect sera anti-toxoplasma antibodies in this community as a measure of their exposure to Toxoplasma gondii. The positive rates for sera anti-toxoplasma antibodies were 21.8% and 19.6%, respectively, in 422 Atayal and 51 hunting dogs tested. Neither of the positive rates were found to be significantly different between male (22.1%) and female Atayal (21.4%), or between humans (21.8%) and dogs (19.6%) (P > 0.05) when compared by the Chi-Squared test (chi 2-test). A significant difference was observed between the positive rates in adults (28.3%) and children (18.7%) (P < 0.05), and the age pattern of prevalence is consistent with an increasing duration of exposure to Toxoplasma gondii with age. The consumption of raw liver of wild animals or insufficiently cooked meat may be the major mode of transmission of toxoplasmosis in Atayal.

Views of obstetric patients who refuse regional anesthesia in cesarean section

BACKGROUND

Regional anesthesia for cesarean section has gained widespread popularity. However, there are still a good few of obstetric patients who refuse it. This study was to investigate the reasons for refusing regional anesthesia in order to gain some insights into the attitudes and concerns of patients.

METHODS

Three hundred and twenty-four obstetric patients scheduled for Cesarean section were interviewed just before entering the operating room. They were asked to give one or two reasons for refusing regional anesthesia.

RESULTS

Two hundreds of them refused regional anesthesia. The most frequent reasons were apprehension of witnessing the operation (auditory or visional) (45.42%) and fear of backache following regional anesthesia (14.58%).

CONCLUSIONS

Anesthesiologists should be aware of patients' feeling or concern and could be capable and willing to discuss with them the relevant problems.

Effects of en bloc esophagectomy on nutritional and immune status in patients with esophageal carcinoma

BACKGROUND AND OBJECTIVES

En bloc esophagectomy has been established as the treatment of choice for patients with resectable esophageal carcinoma. However, an extensive surgical procedure may result in further impairment of the patient's nutritional status and immune system. Thus a prospective study was undertaken to evaluate the perioperative sequential changes in patients' nutritional and immune status and the timing to institute postoperative adjuvant therapy.

METHODS

Thirty-seven patients (34 male, 3 female) who had undergone en bloc esophagectomy with gastric institution for epidermoid carcinoma of the esophagus were studied. The mean age was 62.3 years. The nutritional and immune assessments were performed preoperatively, on the third postoperative day, in the first week, second week, third week, and at the end of the first and third month. The biochemical studies for nutritional evaluation included serum albumin, cholesterol, iron, transferrin, magnesium, zinc, total iron binding capacity (TIBC), and nitrogen balance. Evaluation of the immune status consisted of: (1) total lymphocyte count, (2) lymphocyte subpopulation, (3) immunoglobulins, (4) complements (C3 and C4), (5) lymphocyte blastogenic responses, (6) tumor necrosis factor-alpha and interleukin-2 secretion activity from mononuclear cells, and (7) C-reactive protein (CRP) level.

RESULTS

All the parameters in nutritional assessment declined profoundly by the third postoperative day (P < 0.05). The most severe deterioration was in serum iron, followed by transferrin, TIBC, cholesterol, and zinc. Most of them returned to the preoperative levels within 2-3 weeks after surgery. However, the serum levels of iron, transferrin, and TIBC required a longer period of time (> 1 month) to return to normal. A remarkable increase of serum CRP was detected in the first postoperative week (P < 0.05), but immunoglobulins and complements decreased significantly yet variably (P < 0.05) in the second or third postoperative week before gradually returning to preoperative levels. Moreover, during the first week after surgery, CD3 and CD8 diminished following esophageal surgery, whereas CD20, CD4/CD8 ratio, and lymphocyte blastogenic responses increased significantly (P < 0.05).

CONCLUSIONS

Except for iron-related parameters, all the other nutritional parameters returned to the preoperative level by the third postoperative week. An adequate supplementation of iron and protein for 1-3 months after surgery is needed. En bloc esophagectomy might have only a mild and temporarily adverse effect on the host immune defense. Regarding the postoperative recovery of a patient's nutritional and immune status, postoperative chemo-radiotherapy is optimally instituted after the third postoperative week, instead of within 2 weeks of surgery.

Comparison of local infiltration of tenoxicam and intravenous tenoxicam for postoperative analgesia in herniorrhaphy

BACKGROUND

The major complaint of herniorrhaphy is postoperative pain which occurs during the first 24 h after operation. Tenoxicam has a long half-life of 60-80 h. Local infiltration of the drug concentrates the pain control effects in the local area. The local infiltration dose can be smaller than the recommended systemic dose needfully to reach the target area to be effective. Therefore we studied the effect of preoperative local infiltration of tenoxicam on postoperative pain.

METHODS

Sixty patients, belonging to ASA classes I and II, undergoing unilateral herniorrhaphy, were randomly assigned to 4 groups. General anesthesia was induced with thiamylal 5 mg/kg, fentanyl 2 micrograms/kg, and atracurium 5 mg/kg. Group 1 (G1) patients were preoperatively injected with 10 mg of tenoxicam in 10 ml normal saline or distilled water, in the operative area. Group 2 (G2) and Group 3 (G3) patients were preoperatively given intravenous tenoxicam, 20 mg and 10 mg, respectively. Group 4 (G4) patients were not given preoperative local infiltration or intravenous tenoxicam to serve as control group. The pain score was assessed at 2 h, 9 h, 24 h postoperatively in all groups. We recorded the total amount of acetaminophen used and the form of administration of the analgesic drug. All patients received general anesthesia in uniform technique.

RESULTS

Pain score and amount of analgesic drug required in G1 (local infiltration group) patients were significantly decreased compared with the other groups. The postoperative pain score of Visual Analog Scale (VAS) and analgesic requirement in the four groups were ranked as follows: G1 < G2 < G3 < G4. No significant difference was observed between G2, G3 and G4. Only the pain score in G2 patients significantly decreased (p < 0.05) during the late postoperative period (24 h) when compared with G4 patients.

CONCLUSIONS

Preoperative local infiltration of tenoxicam can decrease postoperative pain score significantly during the most painful period (24 h) in herniorrhaphy.