Microbial ecology and performance of ammonia oxidizing bacteria (AOB) in biological processes treating petrochemical wastewater with high strength of ammonia: effect of Na(2)CO(3) addition

This study evaluated nitrification performance and microbial ecology of AOB in a full-scale biological process, powder activated carbon treatment (PACT), and a pilot-scale biological process, moving bed biofilm reactor (MBBR), treating wastewater collected from a petrochemical industry park. The petrochemical influent wastewater characteristics showed a relative low carbon to nitrogen ratio around 1 with average COD and ammonia concentrations of 310 mg/L and 325 mg-N/L, respectively. The average nitrification efficiency of the full-scale PACT process was around 11% during this study. For the pilot-scale MBBR, the average nitrification efficiency was 24% during the Run I operation mode, which provided a slightly better performance in nitrification than that of the PACT process. During the Run II operation, the pH control mode was switched from addition of NaOH to Na(2)CO(3), leading to a significant improvement in nitrification efficiency of 51%. In addition to a dramatic change in nitrification performance, the microbial ecology of AOB, monitored with the terminal restriction fragment length polymorphism (T-RFLP) molecular methodology, was found to be different between Runs I and II. The amoA-based TRFLP results indicated that Nitrosomonas europaea lineage was the dominant AOB population during Run I operation, while Nitrosospira-like AOB was dominant during Run II operation. To confirm the effects of Na(2)CO(3) addition on the nitrification performance and AOB microbial ecology observed in the MBBR process, batch experiments were conducted. The results suggest that addition of Na(2)CO(3) as a pH control strategy can improve nitrification performance and also influence AOB microbial ecology as well. Although the exact mechanisms are not clear at this time, the results showing the effects of adding different buffering chemicals such as NaOH or Na(2)CO(3) on AOB populations have never been demonstrated until this study.

Effects of glycemic index meal and CHO-electrolyte drink on cytokine response and run performance in endurance athletes

OBJECTIVE

To examine the effect of the glycemic index (GI) of a pre-exercise (PRE-ex) meal on plasma cytokine responses and endurance performance when carbohydrate-electrolyte (CHO-E) drink was consumed during exercise.

METHODS

Eight endurance-trained male runners (age: 28.6+/-2.7 years; body mass: 61.9+/-1.71 kg; V O(2max): 58.5+/-1.6 ml kg(-1)min(-1)) completed three trials in a randomized order. The pre-exercise meal consisted of either high-GI (HGI) (GI=83), low-GI (LGI) foods (GI=36) or control (CON) (low energy sugar-free jelly) was given to the participant 2h before a 21-km performance run on a level treadmill. During each trial, 2 ml kg(-1) BM of 6.6% CHO-E solution was consumed immediately before exercise and every 2.5-km afterward. Blood samples were collected before (pre-meal), and 120 min after ingestion the meal (120 min), immediately (POST), and 60 min (POST-60 min) after exercise.

RESULTS

No difference was found in time to complete the 21-km run between LGI and HGI. The interleukin-6 (IL-6) level increased by more than 100 times immediately after exercise in the three trials and returned to the basal level only on LGI at POST-60 min. In contrast, interleukin-2 (IL-2) level showed a transitory decrease at POST on CON (p<0.001). Glucose concentrations did not recover to the pre-meal level by POST-60 min on HGI only. Cortisol concentrations increased throughout the exercise and were lower on LGI when compared with CON (p<0.05) at POST-60 min.

CONCLUSIONS

HGI and LGI demonstrated similar performance when CHO-E solution was consumed during a 21-km run. However, pre-exercise LGI meal attenuated the increases in cortisol and quickened the recovery of the increased IL-6 value.

Enhanced x-ray irradiation-induced cancer cell damage by gold nanoparticles treated by a new synthesis method of polyethylene glycol modification

We explored a very interesting gold nanoparticle system-pegylated gold in colloidal solution-and analyzed its uptake by mice colorectal adenocarcinoma CT26 tumor cells and the impact on the cell's response to x-ray irradiation. We found that exposure to polyethylene glycol (PEG) modified ('pegylated') 4.7 ± 2.6 nm gold nanoparticles synthesized by a novel synchrotron-based method enhances the response of CT26 cells to x-ray irradiation. Transmission electron microscopy (TEM) and confocal microscopy revealed that substantial amounts of such nanoparticles are taken up and absorbed by the cells and this conclusion is supported by quantitative induced coupled plasma (ICP) results. Standard tests indicated that the internalized particles are highly biocompatible but strongly enhance the cell damage induced by x-ray irradiation. Synchrotron radiation Fourier transform infrared (SR-FTIR) spectromicroscopy analyzed the chemical aspects of this phenomenon: the appearance of C = O stretching bond spectral features could be used as a marker for cell damage and confirmed the enhancement of the radiation-induced toxicity for cells.

Effects of a hot environment on simulated cycling and running performance in triathletes

AIM

This study examined the effects of a hot environment on metabolic responses, thermoregulation, and performance during simulated cycling and running in triathletes.

METHODS

Seven male triathletes completed two trials in moderate (22+/-0.2 degrees C, 76+/-2% relative humidity, M) and hot (31.2+/-0.2 degrees C, 76.4+/-1.6% relative humidity, H) environmental conditions separated by at least 7 days. The subjects were required to complete a self-paced 40 km simulated cycling, followed by a 10 km run on a treadmill for as fast as possible in both trials.

RESULTS

The overall performance time was faster in M than H (M vs H, 119+/-6 min vs 127+/-6 min, P<0.01). Moreover, there were no differences in the cycling time between the two trials, but the run time was faster in M (M vs H, 51+/-4 min vs 59+/-5 min, P<0.05) than in H. Ad libitum water consumption was higher in H than in M (H vs M, 970+/-231 mL min(-1) vs 547+/-131 mL min(-1) P<0.05), and the mean skin temperature was also higher in H than in M throughout the exercise (H vs M, 35.3+/-0.1 vs 33.3+/-0.1 degrees C, P<0.05). However, there were no differences in rectal temperature, blood lactate, blood glucose, body mass change, plasma volume change, osmolality, carbohydrate oxidation, and fat oxidation between the trials.

CONCLUSION

The results suggested that triathletes reduced their running performance after a 40 km simulated cycling when the ambient temperature was high.

Swelling activated chloride currents in the electrical activity of pulmonary vein cardiomyocytes

BACKGROUND

Pulmonary veins (PVs) contain cardiomyocytes with a high arrhythmogenicity for inducing atrial fibrillation. The swelling-activated outwardly rectifying Cl(-) currents (I(Cl,swell)) are important in the electrical activity of cardiomyocytes. This study was to investigate whether I(Cl,swell) play a role in the PV electrophysiological characteristics.

MATERIALS AND METHODS

A whole-cell patch clamp was used to investigate the action potentials and I(Cl,swell) in isolated rabbit single PV and atrial cardiomyocytes during immersion in isotonic (290-300 mosm L(-1)) and hypotonic (220-230 mosm L(-1)) solutions. The cell length and cell width were measured using confocal microscopy.

RESULTS

Hypotonic solution induced larger I(Cl,swell) in the PV cardiomyocytes with pacemaker activity than those in the PV cardiomyocytes without pacemaker activity or atrial cardiomyocytes. Hypotonic solution shortened the action potential duration and increased the cell width to a greater extent in the PV cardiomyocytes than in the atrial cardiomyocytes. Moreover, hypotonic solution decreased the PV firing with a decrease in the transient inward currents and delayed after depolarizations.

CONCLUSIONS

These findings suggest that the I(Cl,swell) plays an important role in the electrical activity of the PV cardiomyocytes.

Whole-body positron emission tomography with 18F-fluorodeoxyglucose is an effective method to detect extra-pelvic recurrence in uterine sarcomas

PURPOSE OF INVESTIGATION

To assess the clinical use of F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) in the post-therapy surveillance of uterine sarcoma.

METHODS

Eight whole-body FDG-PET studies were performed in seven women with previously treated uterine sarcoma. Conventional image studies (computed tomography) and physical examinations were performed for follow-up. All FDG-PET studies were indicated to localize suspected recurrences noted by conventional methods.

RESULTS

The per case sensitivity of the FDG-PET studies and CT scans was 85.7% (6/7) and 100% (7/7), respectively (p = 0.174). FDG-PET was able to detect seven extrapelvic metastastic sites below the diaphragm (7/7, sensitivity: 100%), including the liver, spleen, paraaortic lymph node, spine and paracolic gutter, as well as pulmonary lesions in five patients, while the CT scan detected only three lesions (3/7, sensitivity: 42.9%; p = 0.070). FDG-PET detected only four recurrent pelvic lesions (4/6) and CT scan detected six (6/6) recurrent pelvic lesions (66.7% vs 100%, p = 0.455).

CONCLUSIONS

The FDG-PET showed a better detection rate than the abdominal CT scan for extrapelvic metastatic lesions and a similar detection rate as well as abdominal CT scan. FDG-PET can serve as a useful detection tool for patients with uterine sarcomas because nearly 80% of recurrence involve an extrapelvic site.

Hair follicle: a reliable source of recipient origin after allogeneic hematopoietic stem cell transplantation

Blood, buccal swab and hair follicles are among the most commonly used sources for forensic science, parentage testing and personal identification. A total of 29 patients who have had a sustained engraftment from 15 months to 21.5 years after allogeneic hematopoietic stem cell transplantation (HSCT) without rejection, relapse or chronic GVHD involving oral mucosa were enrolled for a chimerism study. PCR-amplified short tandem repeat analyses were conducted per patient every 3 months for at least three consecutive times. The results for blood were all donor type except one who had a mixed chimerism, 14.5 years after receiving a transplant for lymphoma. As for buccal swab, mixed chimerism ranging from 10 to 96% donor origin was noted for 28 recipients except the one who had mixed chimerism of blood and retained total recipient type. In contrast, hair follicles were 100% recipient type for the entire group. It is concluded that the hair follicle is devoid of adult stem cell plasticity and may serve as a reliable source of recipient's origin when pre-transplant DNA fingerprinting or reference DNA is not available for people who have successfully received allogeneic HSCT while in need of a personal identification.

Hydroxychavicol, a novel betel leaf component, inhibits platelet aggregation by suppression of cyclooxygenase, thromboxane production and calcium mobilization

BACKGROUND AND PURPOSE

Platelet hyperactivity is important in the pathogenesis of cardiovascular diseases. Betel leaf (PBL) is consumed by 200-600 million betel quid chewers in the world. Hydroxychavicol (HC), a betel leaf component, was tested for its antiplatelet effect.

EXPERIMENTAL APPROACH

We tested the effect of HC on platelet aggregation, thromboxane B(2) (TXB(2)) and reactive oxygen species (ROS) production, cyclooxygenase (COX) activity, ex vivo platelet aggregation and mouse bleeding time and platelet plug formation in vivo. The pharmacokinetics of HC in rats was also assessed.

KEY RESULTS

HC inhibited arachidonic acid (AA) and collagen-induced platelet aggregation and TXB(2) production. HC inhibited the thrombin-induced TXB(2) production, but not platelet aggregation. SQ29548, suppressed collagen- and thrombin-induced TXB(2) production, but not thrombin-induced platelet aggregation. HC also suppressed COX-1/COX-2 enzyme activity and the AA-induced ROS production and Ca(2+) mobilization. HC further inhibited the ex vivo platelet aggregation of platelet-rich plasma (>100 nmole/mouse) and prolonged platelet plug formation (>300 nmole/mouse) in mesenteric microvessels, but showed little effect on bleeding time in mouse tail. Moreover, pharmacokinetics analysis found that more than 99% of HC was metabolized within 3 min of administration in Sprague-Dawley rats in vivo.

CONCLUSIONS AND IMPLICATIONS

HC is a potent COX-1/COX-2 inhibitor, ROS scavenger and inhibits platelet calcium signaling, TXB(2) production and aggregation. HC could be a potential therapeutic agent for prevention and treatment of atherosclerosis and other cardiovascular diseases through its anti-inflammatory and antiplatelet effects, without effects on haemostatic functions.

Study on the effects of mechanical pressure to the ultrastructure and secretion ability of mandibular condylar chondrocytes

During mandibular movement, condyle is subjected to repetitive compression and the mandibular condylar chondrocytes (MCCs) can detect and respond to this biomechanical environment by altering their metabolism. The present study was undertaken to investigate the effects of pressure to the ultrastructure, aggrecan synthesis, nitric oxide (NO) and prostaglandin F(1)alpha(PGF(1)alpha) secretion in MCCs. In vitro cultured rabbit MCCs were incubated and pressed under continuous pressure of 90kPa for 60min and 360min by hydraulic pressure controlled cellular strain unit. The ultrastructure, aggrecan mRNA expression, activity of nitric oxide synthase (NOS) and PGF(1)alpha secretion were investigated. Besides, nitric oxide inhibitor was used together with pressure to investigate the role of NO in mechanical effects. The appearance of MCC on TEM showed that after been pressed under 90kPa for 60min, the cellular processes became elongated and voluminous, together with aggrecan mRNA increasing. Under 90kPa for 360min, some of the cells showed distinct sign of apotosis and the aggrecan mRNA decreased. Pressure of 90kPa could cause increase of NOS activity and decrease of PGF(1)alpha composition. Inhibitor experiments indicated that pressure-induced upregulation of aggrecan mRNA and inhibition of PGF(1)alpha synthesis was partly mediated by NO. Continuous pressure could cause changes on the ultrastructure and function of MCC, as well as up-regulation of aggrecan synthesis, increase of NO secretion and decrease of PGF(1)alpha composition. NO was the upstream molecule, which mediated the response of aggrecan and PGF(1)alpha to mechanical pressure.

Effect of a periodized exercise training and active recovery program on antitumor activity and development of dendritic cells

AIM

Dendritic cells (DCs) are potent antigen-presenting cells that promote antitumor immunity in vivo when pulsed with tumor antigen. No studies have indicated that exercise training affects DC function. The purpose of this study was to investigate the effect of a 5-week periodized exercise training and active recovery program on the development of DCs, and to test their effect on the antitumor immunity of mononuclear cells (MNC) from blood and spleen against human leukemic U937 and murine lymphoma Yac-1 cells, respectively.

METHODS

Male Fisher 344 rats were divided into 2 groups: exercise and non-exercise group. The training protocol consisted of running on a motor-driven treadmill 6 days a week for consecutive 5 weeks, during which the running time, treadmill speed, and incline gradient were increased weekly. Active recovery parameters were set at 30% of the intensity of the previous day.

RESULTS

DC numbers increased significantly (P<0.05) in the exercise group compared to controls, but there were no significant changes in the expression of surface antigens CD80 and CD86. In exercise group MNC-conditioned medium (CM) prepared with 50 microg/mL phytohemagglutinin (PHA) significantly inhibited proliferation of U937 cells, and splenocyte-CM with PHA at 20 and 40 microg/mL significantly inhibited proliferation of YAC-1 cells greater than control group.

CONCLUSIONS

The 5-week periodized exercise training with active recovery promotes the number of DCs and enhances the activity of DCs against tumor cells.

Novel polymorphisms in exons 6 and 7 of A/B alleles detected by polymerase chain reaction-single strand conformation polymorphism

BACKGROUND AND OBJECTIVES

The ABO blood group system is the most important blood group system in transfusion medicine. In addition to the major A, B and O alleles, many rare alleles have been defined. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and analysis by PCR sequence specific primers (SSP) are commonly conducted for genotyping but have the limitation of being unable to detect unknown substitution(s) in amplified DNA fragments, whereas PCR-single strand conformation polymorphism (SSCP) can be used for both.

MATERIALS AND METHODS

Three-hundred unrelated blood donors of the AB phenotype were enrolled. Four pairs of primers were designed to constitute two sets of multiplex PCRs: this amplifies four fragments spanning the entire exon 6 and its immediate flanking regions, nucleotides 432-1065, as well as the 3' untranslated region of exon 7 of the ABO gene. The SSCP electrophoresis was carried out on a 12.5% polyacrylamide gel in a GenePhor electrophoresis unit. For those with unexpected banding patterns, SSCP analyses were performed in duplicate and samples were cloned and sequenced for exons 6 and 7.

RESULTS

Seven samples were noted to have six variant alleles, of which five have not been previously reported in the literature. Of these five novel variants, four were derived from the B allele, while the other derived from the A allele.

CONCLUSIONS

By using PCR-SSCP, five novel A/B alleles were found.

Effects of mechanical pressure on intracellular calcium release channel and cytoskeletal structure in rabbit mandibular condylar chondrocytes

Many signal molecules are involved in mechanotransduction process, among which intracellular calcium and cytoskeleton are two of the most important ones. This study investigated the changes of intracellular calcium and cytoskeleton under pressure and the effects of intracellular calcium variation on cytoskeleton responses to the pressure in rabbit mandibular condylar chondrocytes (MCCs). In vitro cultured MCCs from 2-week-old New Zealand rabbits were incubated for observation of intracellular calcium variation under laser scanning microscope. Coomassie BB staining was used to observe the characteristics of cytoskeleton. We found that intracellular calcium increased following the irritation by 1,25(OH)2D3, whereas it remained unchanged when inositol triphosphate receptor (IP3R) channel was blocked by heparin. Pretreatment with pressure of 90 kPa for 60 min enhanced the sensitivity of IP3R channel and caused higher intracellular calcium concentration. The cytoskeletons of MCCs were revealed correspondingly uniform and reticular in the control, most of which showed higher expression in tighter arrangement under continuous pressure of 90 kPa for 60 min but lower expression when the pressure time was prolonged to 360 min. When MCCs were pretreated with heparin, the cytoskeleton of them displayed sparsely and discontinuously under 90 kPa for 60 min. To sum up, both cytoskeleton and intracellular calcium participate in the transition process of mechanical signal to biological effects of MCC. However, the decrease of intracellular calcium resulted from IP3R channel blocking obviously interferes the recomposition of cytoskeleton under mechanical pressure, which suggests that calcium message is indispensable to the cytoskeleton response of MCC under pressure.

An unusual clinical characterization of a male with distal partial trisomy 1q42.1 and monosomy 4q35.1 and review of the literature

We report a male patient with a karyotype of 46,XY, der(4)t(1;4)(q42.1;q35.1) inherited from a maternal balanced translocation involving chromosome 1q and 4q. The boy had corpus callosum dysgenesis, laryngomalacia, tracheobronchus, facial dysmorphism, simian creases, and developmental retardation. The first three features are unique compared to previous literature reports on distal partial trisomy 1q. This case report allows a further delineation of the distal partial trisomy 1q syndrome.

Effects of TGF-beta s on the growth, collagen synthesis and collagen lattice contraction of human dental pulp fibroblasts in vitro

Transforming growth factor-beta (TGF-beta) is important in regulating the repair and regeneration of damaged dental pulp. For further elucidating the roles of different isoforms of TGF-beta in the healing and inflammatory processes of human dental pulp, we found that TGF-beta1, TGF-beta2 and TGF-beta3 inhibited the growth of two human dental pulp cell strains in vitro by 19-29, 18-25 and 23-26%, respectively, at a concentration of 0.5 ng/ml. TGF-beta also differentially stimulated the collagen synthesis of pulp cells. Collagen synthesis increased by 1 ng/ml of TGF-beta1 and TGF-beta2 by 42 and 51%, respectively. TGF-beta3 (0.1-1 ng/ml) lacked of stimulatory effect on collagen synthesis of pulp cells. Pulp cells have the intrinsic capacity to contract collagen lattice, leading to decreasing of lattice diameter. An 8 h exposure to TGF-beta1 and TGF-beta2 enhanced the pulp cell-populated collagen lattice contraction at concentrations ranging from 0.2 to 3 ng/ml. At similar concentrations, TGF-beta3 lacked of this stimulatory effect. When collagen lattice were detached after 24 h of exposure, TGF-beta1 and TGF-beta2 (0.6-3 ng/ml) induced the pulp cells-populated collagen lattice contraction within 4-8h of gel detachment. These results indicate that TGF-beta-induced collagen lattice contraction is a late cellular event. These in vitro results indicate that effects of TGF-beta isoforms on the growth, collagen synthesis and collagen lattice contraction of pulp cells may play crucial roles in the pathobiological processes of dental pulp.

Evaluation of factors influencing root-induced changes of copper fractionation in rhizosphere of a calcareous soil

Major factors influencing the root-induced copper fractionation changes within the rhizosphere of maize, wheat, pea, and soybean seedlings were evaluated using a contaminated calcareous soil. The effects of acidification, alkalization, and introduction of root exudates were investigated by addition of acid, alkaline and root exudates from solution cultures, prior to incubation and copper fractionation. Raw and sterilized soils were compared for changes of copper fractionation in the rhizosphere using rhizoboxes with maize, wheat, pea and soybean seedlings. The results indicated that the general trend in considerable changes was similar among the plant species studied. The rhizosphere experienced a depletion of carbonate associated and organic bound copper along with an accumulation of exchangeable and Fe-Mn oxide bound copper. The resulting significant influence of root exudates on copper fractionation appears to have been produced through complexation rather than acidification or alkalization. The increase in exchangeable copper in rhizosphere was strengthened by microorganisms.

The prevalence and spectrum of alpha and beta thalassaemia in Guangdong Province: implications for the future health burden and population screening

AIM

Thalassaemia is a good candidate disease for control by preventive genetic programmes in developing countries. Accurate population frequency data are needed for planning the control of thalassaemia in the high risk Guangdong Province of southern China.

METHODS

In total, 13397 consecutive samples from five geographical areas of Guangdong Province were analysed for both haematological and molecular parameters.

RESULTS

There was a high prevalence of carriers of alpha thalassaemia (8.53%), beta thalassaemia (2.54%), and both alpha and beta thalassaemia (0.26%). Overall, 11.07% of the population in this area were heterozygous carriers of alpha and beta thalassaemia. The mutation spectrum of alpha and beta thalassaemia and its constitution were fully described in this area. This study reports the true prevalence of silent alpha thalassaemia in the southern China population for the first time. In addition, two novel mutations that give rise to alpha thalassaemia, one deletion resulting in beta thalassaemia, and a rare deletion (--(THAI) allele) previously unreported in mainland China were detected. The frequency of the most common mutation, the Southeast Asian type of deletion (--(SEA), accounting for 48.54% of all alpha thalassaemias) was similar to the total of two alpha(+) thalassaemia deletions (-alpha(3.7) and -alpha(4.2), accounting for 47.49% of alpha thalassaemia).

CONCLUSION

Both alpha and beta thalassaemia are widely distributed in Guangdong Province of China. The knowledge gained in this study will enable the projected number of pregnancies at risk to be estimated and a screening strategy for control of thalassaemia to be designed in this area.

Tamoxifen-induced endometrial cancer

OBJECTIVE

Tamoxifen-induced endometrial changes in postmenopausal women with breast carcinoma are well-known. Due to the popularity of postoperative chemotherapy for breast cancer, chemotherapy-induced early menopause in women with breast cancer on tamoxifen treatment needs more attention, because these women have higher risk for endometrial cancers than premenopausal women.

SUBJECT

From May 1995 to May 1997, three premenopausal women aged 46, 43, and 39 with breast cancer were treated in our center. All patients received standard surgery for their breast cancers followed by six courses of adjuvant chemotherapy and 5-year tamoxifen treatment. All patients were regularly followed-up at the Breast Cancer Center and evaluated annually at the gynecological clinics including pelvic examination, Pap smear and transvaginal sonography.

RESULTS

All patients became menopausal after six courses of chemotherapy ranging from three months to 14 months. The endometrial cancers occurred at 36 months, 28 months, and 33 months, respectively, after initial treatment for the breast cancers. Their last gynecologic examinations performed at six months, eight months and five months before the diagnosis of endometrial cancer showed nothing remarkable. Only one patient complained of vaginal spotting before diagnosis and the other two patients only complained of increasing purulent vaginal discharge. All patients received standard treatment for endometrial cancer and none of them died of their disease but one patient died of recurrent breast cancer 52 months later.

CONCLUSION

Women with breast cancer on tamoxifen treatment need more attention and frequent evaluation of their reproductive organs, especially postmenopausal (either spontaneous or chemotherapy induced) women, although the American College of Obstetricians and Gynecologists (ACOG) comments that no more than annual pelvic exams with Pap smears are needed in asymptomatic women.

Anti-leukemic immunity against U937 cells in uremic patients

To examine anti-tumor immunity in uremic patients undergoing regular hemodialysis, we designed this study using in vitro mononuclear cell (MNC) cultures, with human leukemic U937 cells as the target. MNC were collected and cultured from uremic subjects and age- and gender-matched healthy controls. Conditioned media from the cultures (MNC-CM) were collected after stimulation with various concentrations of phytohemagglutinin (PHA). The proliferation-inhibiting and differentiation-inducing activities of the PHA-MNC-CM on U937 cells were evaluated. The growth inhibition activity of uremic patients' PHA-MNC-CM was lower than that of controls. The differentiation-inducing effects were evaluated by morphological scoring, superoxide production, and monocyte-associated antigen expression (CD14 and CD68). All three parameters demonstrated that the differentiation-inducing effect of MNC-CM increased with increasing doses of PHA. These effects, however, were significantly less in uremic patients compared to controls at higher doses of PHA. The levels of TNF-alpha and IFN-gamma in PHA-MNC-CM increased in a PHA dose-dependent manner and were much higher in the controls. We conclude that the capacity of MNC from uremic hemodialysis patients to produce anti-leukemic immunity is significantly lower than that of healthy controls.

Intraperitoneal cancer spread after laparoscopic cystectomy for mature teratoma with malignant transformation

Laparoscopic surgery for ovarian dermoid cysts has been accepted. However, its potential limitations should be considered, including technique difficulty, intraoperative tumor spillage and malignant transformation. We report a case of ovarian dermoid cysts with malignant transformation that was initially treated using laparoscopic cystectomy, but was complicated by intraperitoneal tumor dissemination.

Effects of sediment phosphorus release associated with the density current on water quality of a subtropical and deep reservoir in Taiwan

It was found that the increase of sediment P release in the anoxic state associated with the density current initiated by the cold front in the winter was the cause of the deterioration of the water quality of the subtropical, noncalcareous and deep reservoir, Feitsui Reservoir, in recent years. A mathematical model including the analytical solutions of the transport of the density current combined with a simple 2-layered water quality model has been established, describing the hydrodynamics and the water quality variation of the reservoir well. The continued sediment release of P in the anoxic state (from October to March) is an important P source and should be carefully assessed and controlled to reduce the impact of the internal loading of P incorporated with the density current on the water quality in future years.

Changes of copper speciation in maize rhizosphere soil

Chemical forms of copper in the rhizosphere and bulk soil of maize were investigated using rhizobox cultivation and sequential extraction techniques. The copper accumulations were also determined. The results demonstrated that there were continuous changes in copper fractionation within the maize rhizosphere. Initially, the amount of exchangeable copper increased before dropping below the initial level after 40 days or so. Carbonate associated copper followed a similar trend of change, but with a slower pace than the exchangeable copper. The increase in carbonate associated copper only become evident after 30 days, with the net loss occurring after 60 days. There were also initial increases in oxide bound copper as well as decreases in the organic matter associated copper, both followed by a turnover after 40-50 days. The accumulation of copper in the maize plant was found to be biomass dependent. The amount of accumulated copper absorbed in the plant material exceeded the initial quantity of the exchangeable copper in the soil, revealing a transformation from less bioavailable to more bioavailable fractions. During cultivation, decreases in redox potential and increases in pH, dissolved organic carbon (DOC), and microbial activity in the maize rhizosphere were observed. The change in copper speciation may result from root-induced changes in DOC, redox potential, and microbial activity in the rhizosphere.

The effects of exercise training on walking function and perception of health status in elderly patients with peripheral arterial occlusive disease

OBJECTIVE

To determine the effects of 12-week exercise programme on ambulatory function, free-living daily physical activity and health-related quality of life in disabled older patients with intermittent claudication.

DESIGN

Prospective, randomized controlled trial.

SETTING

University Medical Center and Veterans Affairs Medical Center, Taipei, Taiwan.

SUBJECTS

Thirty-two of 64 patients with Fontaine stage II peripheral arterial occlusive disease (PAOD) were randomized to exercise training and 32 to usual care control. Five patients from the exercise group and six patients from the control group dropped out, leaving 27 and 26 patients, respectively, completing the study in each group.

INTERVENTIONS

Twelve weeks of treadmill exercise training.

MAIN OUTCOME MEASURES

Treadmill walking time to onset of claudication pain and to maximal claudication pain, 6-min walk distance, self-reported ambulatory ability and perceived health-related quality of life (QOL).

RESULTS

Compliance of exercise programme was 83% of the possible sessions. Exercise training increased treadmill walking time to onset of claudication pain by 88% (P < 0.001), time to maximal pain by 70% (P < 0.001), and 6-min walk distance by 21% (P < 0.001).

SUBJECTS

Perception of health-related QOL improved from 12% to 178% in the exercise group. These improvements were significantly better than the changes in the control group (P < 0.05).

CONCLUSIONS

Significant improvements in claudication following 12-week exercise training in elderly PAOD patients were observed. Increase in treadmill walking time to maximal claudication pain in these patients translated into the improvement of perceived physical health, which enabled the patients to become more functionally independent.