Viral evolution in response to the broad-based retroviral protease inhibitor TL-3

TL-3 is a protease inhibitor developed using the feline immunodeficiency virus protease as a model. It has been shown to efficiently inhibit replication of human, simian, and feline immunodeficiency viruses and therefore has broad-based activity. We now demonstrate that TL-3 efficiently inhibits the replication of 6 of 12 isolates with confirmed resistance mutations to known protease inhibitors. To dissect the spectrum of molecular changes in protease and viral properties associated with resistance to TL-3, a panel of chronological in vitro escape variants was generated. We have virologically and biochemically characterized mutants with one (V82A), three (M46I/F53L/V82A), or six (L24I/M46I/F53L/L63P/V77I/V82A) changes in the protease and structurally modeled the protease mutant containing six changes. Virus containing six changes was found to be 17-fold more resistant to TL-3 in cell culture than was wild-type virus but maintained similar in vitro replication kinetics compared to the wild-type virus. Analyses of enzyme activity of protease variants with one, three, and six changes indicated that these enzymes, compared to wild-type protease, retained 40, 47, and 61% activity, respectively. These results suggest that deficient protease enzymatic activity is sufficient for function, and the observed protease restoration might imply a selective advantage, at least in vitro, for increased protease activity.

Tests for physical function of the elderly with knee and hip osteoarthritis

This study reports the results of a battery of physical function tests used to assess physical function of older patients with clinical knee and/or hip osteoarthritis (OA), and the correlation to the WOMAC Index (disease-specific questionnaire). A total of 106 sedentary subjects, aged >60 years (mean 69.4, S.D. 5.9) with hip and/or knee OA (mean 12.2 yrs, S.D. 11.0) participated in the study. Mobility, joint flexibility and muscle strength were evaluated by recording time to: walk a distance of 8', ascend/descend 4 stairs, rise from/sit down from a chair (5 times). Hip/knee flexion and isometric quadriceps strength were also measured. Categories of performance were formed by dividing data into quartiles for each test (1=highest, 4=lowest score, 5=unable to complete) and, by summing the category scores, a total summary score (TSS) was obtained. The battery of physical function tests showed an acceptable test-retest reliability (ICC of all tasks > or =0.80) and internal consistency (Cronbach's alpha > or =0.80). Performance scores on walking, stair climb, chair-rise and ROM of affected OA joints were significantly correlated with each other, and with the WOMAC Index (P<0.05, Spearman's correlation). Lower scores on the TSS were associated with lower scores on all the WOMAC Index items (P<0.001). This study shows that a simple battery of physical function tests in combination with the WOMAC Index are reliable and may be useful outcome measures in the evaluation of therapeutic interventions and geriatric rehabilitation.

Molecular basis for the relative substrate specificity of human immunodeficiency virus type 1 and feline immunodeficiency virus proteases

We have used a random hexamer phage library to delineate similarities and differences between the substrate specificities of human immunodeficiency virus type 1 (HIV-1) and feline immunodeficiency virus (FIV) proteases (PRs). Peptide sequences were identified that were specifically cleaved by each protease, as well as sequences cleaved equally well by both enzymes. Based on amino acid distinctions within the P3-P3' region of substrates that appeared to correlate with these cleavage specificities, we prepared a series of synthetic peptides within the framework of a peptide sequence cleaved with essentially the same efficiency by both HIV-1 and FIV PRs, Ac-KSGVF/VVNGLVK-NH(2) (arrow denotes cleavage site). We used the resultant peptide set to assess the influence of specific amino acid substitutions on the cleavage characteristics of the two proteases. The findings show that when Asn is substituted for Val at the P2 position, HIV-1 PR cleaves the substrate at a much greater rate than does FIV PR. Likewise, Glu or Gln substituted for Val at the P2' position also yields peptides specifically susceptible to HIV-1 PR. In contrast, when Ser is substituted for Val at P1', FIV PR cleaves the substrate at a much higher rate than does HIV-1 PR. In addition, Asn or Gln at the P1 position, in combination with an appropriate P3 amino acid, Arg, also strongly favors cleavage by FIV PR over HIV PR. Structural analysis identified several protease residues likely to dictate the observed specificity differences. Interestingly, HIV PR Asp30 (Ile-35 in FIV PR), which influences specificity at the S2 and S2' subsites, and HIV-1 PR Pro-81 and Val-82 (Ile-98 and Gln-99 in FIV PR), which influence specificity at the S1 and S1' subsites, are residues which are often involved in development of drug resistance in HIV-1 protease. The peptide substrate KSGVF/VVNGK, cleaved by both PRs, was used as a template for the design of a reduced amide inhibitor, Ac-GSGVF Psi(CH(2)NH)VVNGL-NH(2.) This compound inhibited both FIV and HIV-1 PRs with approximately equal efficiency. These findings establish a molecular basis for distinctions in substrate specificity between human and feline lentivirus PRs and offer a framework for development of efficient broad-based inhibitors.

Gender discrepancy observed between chemotherapy-induced emesis and hiccups

The aim of this paper was to describe striking gender differences observed between emesis and hiccups in patients receiving cisplatin-based chemotherapy (CT) and one of two dexamethasone-containing anti-emetic regimens. Four hundred patients were evaluated in a crossover study with two arms. Patients in arm A received three doses of ondansetron 8 mg i.v. at 4-h intervals plus dexamethasone 20 mg i.v. from the start of CT, followed by dexamethasone 5 mg i.v. every 12 h, until CT was complete, after which dexamethasone was discontinued. For patients in arm B the treatment was the same as in arm A except that the three doses of ondansetron 8 mg i.v. were given at 24-h intervals. There were 363 patients in arm A and 358 patients in arm B. Vomiting/nausea/hiccups were observed in 30.3%/41.6%/23.7% of patients in arm A and 28.8%/39.1%/23.7% of patients in arm B, respectively. Comparison showed that the rates for complete control of vomiting and nausea on days 1 through 6 were significantly lower in women (P<0.0001 and =0.0004 in arm A and P<0.0001 and <0.0001 in arm B, respectively). Men had a significantly higher incidence of hiccups (P<0.0001 in both arms), but no apparent associations with age, cisplatin dose, tumor type, and the presence of vomiting and nausea during CT were found. Hiccups usually began 24 h after cisplatin administration and persisted for some days. Women had significantly higher rates of vomiting and nausea. The cause of the gender discrepancy is unknown.

Long-term care services needs for spinal-cord injury patients in Taiwan

According to official health statistics, accidents and their adverse effects are the third leading cause of death in Taiwan. More accident victims are surviving thanks to treatment using high medical technology, but this results in many disabled patients with irreversible impairments. The demand for long-term care (LTC) services for spinal cord injury (SCI) patients has thus become a major concern. However, homebound SCI patients may easily face exclusion from LTC services because they are often ineligible for benefits under the regulations of National Health Insurance (NHI). The purposes of this study were: 1. To quantify the LTC needs of SCI patients, and 2. To evaluate the correlation between SCI patient health status and LTC needs. A total of 133 samples were visited from Kaohsiung City and Pingtung County. The results of this study showed that the average age of subjects was 43.15, with 72.9% male. The health status of most of the research subjects was fair (M = 2.33). The test of physiological health status was a 20-item scale with a five-point response format. The worst dysfunctions were urination (M = 3.36, SD = 1.06), sexual function (M = 3.30, SD = 0.88), excretion (M = 3.26, SD = 1.06), comfort (M = 3.25, SD = 0.84), and mobility (M = 2.75, SD = 1.11). All of the above items showed higher mean scores than average. More than one third of the subjects (36.8%) used wheelchairs, had better mobility and went out often. However, half of subjects were completely bedridden (45.9%). The mean psychosocial health status was poor with a mean score of 2.80 which showed higher mean score than average. The subjects were less satisfied with role function (M = 2.92), emotional stability (M = 2.92), and application for community resources (M = 2.79). The most needed LTC services for SCI patients was home-making services; referral and monitoring services ranked second. Suggestions derived from this study were to coordinate nursing care services with social support services for LTC patients and to allocate LTC resources based on patients' health status and their need for LTC services.

Streptococcal brain abscess: analysis of clinical features in 20 patients

BACKGROUND

To assess the clinical features and therapeutic outcomes of brain abscess caused by streptococci.

METHODS

Twenty patients, 18 males and 2 females, aged 3 to 76 years, collected over a 14-year period, have been identified at Kaohsiung Chang Gung Memorial Hospital.

RESULTS

Among these 20 patients, 13 had viridans streptococci infection alone, one had non-A, non-B, and non-D streptococci infection alone, and the other 6 had mixed infections each including streptococci. The locations of all of the abscesses were supratentorial. Among these patients, 18 had a single abscess and 2 had multiple abscesses. Underlying conditions were common in our patients, including head trauma, heart disease, otopharyngeal infection, and medical procedures. Nineteen patients were treated surgically and 1 was treated with antibiotics alone. Nineteen survived and 1 died, with an overall mortality rate of 5%.

CONCLUSION

The clinical presentations and underlying conditions varied according to the different streptococcal species. Streptococcal brain abscesses accounted for 17% of our cases with brain abscesses, and 30% of our streptococcal infections had polymicrobial infections. Although streptococcal brain abscesses were commonly associated with otopharyngeal infections or infectious endocarditis, they also appeared to be often related to neurosurgical events or medical procedures in recent years. Based on our study, prognosis is favorable with early diagnosis and prompt treatment.

Cloning and characterization of a complementary DNA encoding a human epididymis-associated disintegrin and metalloprotease 7 protein

Mammalian spermatozoa interact with the proteins secreted by the epididymis to develop fertility. Transmembrane proteins that possess a disintegrin and metalloprotease (ADAM) domains are shown to be closely related to spermatogenesis and fertilization. Our previous study demonstrated that GP-83, a glycoprotein secreted by the epididymis, was conjugated to mature sperm. In this study, a 2.1-kilobase (kb) GP-83-expressing insert was isolated from a cDNA library of human epididymis by immunoscreening using GP-83-specific antiserum. The 5' end rapid amplification of cDNA ends (RACE) and 3'-RACE of the 2.1-kb insert elucidated two isoforms of GP-83-encoding cDNA sequences, an alpha-form of 3451 base pairs (bp) and beta-form of 2643 bp. Both forms exhibit the same open reading frame of 2262 bp predicting a peptide of 754 amino acid residues. Deduced amino acid sequence revealed signal sequence, prodomain, metalloproteinase, disintegrin, cysteine-rich, epidermal growth factor-like, transmembrane, and cytoplasmic domains. The GP-83-encoding sequence was recognized as human ADAM7 due to significant homology to other ADAM7s. According to the DNA sequences elucidated in the Human Genome Project, h-ADAM7 was located at chromosome 8p22. Ex vivo expression confirmed that h-ADAM7 cDNA did encode GP-83. Northern blot analysis revealed two transcripts of 4 kb and 3 kb in the epididymis, but not in testis or other major tissues. These results indicate that the GP-83-encoding gene is a human epididymis-associated ADAM7 gene (human ADAM7, h-ADAM7) and may be involved in the sperm-egg interaction.

Analysis of large-volume DNA markers and polymerase chain reaction products by capillary electrophoresis in the presence of electroosmotic flow

We have demonstrated on-line concentration and separation of DNA in the presence of electroosmotic flow (EOF) using poly(ethylene oxide) (PEO) solutions. After injecting large-volumes DNA samples, PEO solutions entered a capillary filled with 400 mM Tris-borate (TB) buffers by EOF and acted as sieving matrices. DNA fragments stacked between the sample zone and PEO solutions. Because sample matrixes affected PEO adsorption on the capillary wall, leading to changes in EOF, migration time, concentration, and resolving power varied with the injection length. When injecting phiX174 RF DNA-HaeIII digest prepared in 5 mM Tris-HCl buffer, pH 7.0, at 250 V/cm, peak height increased linearly as a function of injection volume up to 0.9 microl (injection time 150 s). The sensitivity improvement was 100-fold compare to that injected at 25 V/cm for 10 s (0.006 microl). When injecting 1.54 microl of GeneScan 1000 ROX, the sensitivity improvement was 265-fold. The sensitivity improvement was 40-fold when injecting 0.17 microl DNA sample containing pBR 322/HaeIII, pBR 328/BglI, and pBR 328/HinfI digests prepared in phosphate-buffered saline. This method allows the analysis of polymerase chain reaction (PCR) products amplified after 17 cycles when injecting 0.32 microl (at 30 cm height for 300 s). The total analysis time was shorter (91.6 min) than that (119.6 min) obtained from injecting PCR products after 32 cycles for 10 s.

Cell cycle effects of IL-10 on malignant B-1 cells

IL-10 is overexpressed in human chronic lymphocytic leukemia (CLL), and is an autocrine growth factor involved in the development of malignant B1 clones in NZB mice, a murine model for CLL. Antisense IL-10 oligonucleotide treatment induces apoptosis and cell cycle disruption in these cells both in vitro and in vivo. In addition, NZB IL-10 knock-out mice fail to develop the B-1 clones. Dampening of IL-10 protein production via antisense IL-10 oligonucleotide treatment is correlated with decreased p27/Kip1 protein expression which results in increased cyclin D2, cyclin E and cyclin A associated kinase activity. The action of the antisense oligonucleotides is through alterations in cell cycle regulation, resulting in accelerated cell cycle progression, a G2/M block which culminates in apoptosis induction in the malignant cells. This implies that the role of IL-10 as an autocrine growth factor in malignant B-1 cells lies in its ability to inhibit apoptosis induction through the maintenance of sustainable cell cycle progression in malignant cells.

Kinetic characteristics of bacterial azo-dye decolorization by Pseudomonas luteola

A Pseudomonas luteola strain expressing azoreductase activity was utilized to remove the color of an azo dye (reactive red 22) from contaminated solutions. The effects of substrate concentrations, medium compositions, and operation parameters (e.g., pH, temperature, dissolved oxygen, etc.) on decolorization of the azo dye by a P. luteola strain were systematically investigated to reveal the key factors that dominate the performance of azo-dye decolorization. The metabolites resulting from bacterial decolorization were analyzed by high-performance liquid chromatography (HPLC) and mass spectrometery (MS). The results show that the dissolved oxygen and glucose concentration retarded decolorization of reactive red 22 by P. luteola. The optimal azo-dye decolorization occurred at 37 degrees C, while more rapid decolorization took place over pH 7-9. Yeast extract and tryptone strongly enhanced the decolorization. The Michaelis-Menten model can satisfactorily describe the dependence of specific decolorization rate on the concentration of substrate (reactive red 22 or yeast extract). Decolorization of the azo dye by intact cells of P. luteola was essentially independent of the growth phase, whereas the azoreductase activity of the cell-free extract decreased in the order of late-stationary phase > early-stationary phase > mid-log phase. This suggests that mass transfer of the azo dye across the cell membrane may be the rate-limiting step. The HPLC and MS analyses suggest that both partial reduction and complete cleavage of the azo bond could contribute to decolorization of reactive red 22 by P. luteola.

Specific binding of single-stranded telomeric DNA by Cdc13p of Saccharomyces cerevisiae

Cdc13p is a single strand telomere-binding protein of Saccharomyces cerevisiae; its telomere-binding region is within amino acids 451-693, Cdc13(451-693)p. In this study, we used purified Cdc13p and Cdc13(451-693)p to characterize their telomere binding activity. We found that the binding specificity of single-stranded TG(1-3) DNA by these two proteins is similar. However, the affinity of Cdc13(451-693)p to DNA was slightly lower than that of Cdc13p. The binding of telomeric DNA by these two proteins was disrupted at NaCl concentrations higher than 0.3 m, indicating that electrostatic interaction contributed significantly to the binding process. Because both proteins bound to strand TG(1-3) DNA positioned at the 3' end, the 5' end, or in the middle of the oligonucleotide substrates, our results indicated that the location of TG(1-3) in single-stranded DNA does not appear to be important for Cdc13p binding. Moreover, using DNase I footprint analysis, the structure of the telomeric DNA complexes of Cdc13p and Cdc13(451-693)p was analyzed. The DNase I footprints of these two proteins to three different telomeric DNA substrates were virtually identical, indicating that the telomere contact region of Cdc13p is within Cdc13(451-693)p. Together, the binding properties of Cdc13p and its binding domain support the theory that the specific binding of Cdc13p to telomeres is an important feature of telomeres that regulate telomerase access and/or differentiate natural telomeres from broken ends.

Renaturation and stabilization of the telomere-binding activity of Saccharomyces Cdc13(451-693)p by L-arginine

Production of recombinant proteins can be valuable in studying their biological functions. However, recombinant proteins expressed in Escherichia coli sometimes form undesirable insoluble aggregates. Solubilization and renaturation of these aggregates becomes a problem that one needs to solve. Here we used recombinant Cdc13(451-693)p as example to show the presence of l-arginine during renaturation greatly enhanced the renaturation efficiency. Cdc13p is the single-stranded telomere-binding protein of yeast Saccharomyces cerevisiae. The telomere-binding domain has been mapped within amino acids 451-693 of Cdc13p, Cdc13(451-693)p. Recombinant Cdc13(451-693)p was expressed in E. coli as insoluble protein aggregates. Purification of insoluble Cdc13(451-693)p was achieved by denaturing the protein with 6 M guanidine-HCl and followed by Ni-nitrilotriacetic acid agarose column chromatography. Renaturation of Cdc13(451-693)p to the active form was achieved by dialyzing denatured protein in the presence of l-arginine. Moreover, the presence of l-arginine was also helped in maintaining the telomere-binding activity of Cdc13(451-693)p. Taking together, l-arginine might have a general application in renaturation of insoluble aggregates.

Separation of dsDNA in the presence of electroosmotic flow under discontinuous conditions

Separations of phiX-174/HaeIII DNA restriction fragments have been performed in the presence of electroosmotic flow (EOF) using five different polymer solutions, including linear polyacrylamide (LPA), poly(ethylene oxide) (PEO), hydroxypropylcellulose (HPC), hydroxyethylcellulose (HEC), and agarose. During the separation, polymer solutions entered the capillary by EOF. When using LPA solutions, bulk EOF is small due to adsorption on the capillary wall. On the other hand, separation is faster and better for the large DNA fragments (> 872 base pairs, bp) using derivative celluloses and PEO solutions. Several approaches to optimum resolution and speed by controlling EOF and/or altering electrophoretic mobility of DNA have been developed, including (i) stepwise changes of ethidium bromide (0.5-5 microg/mL), (ii) voltage programming (125-375 V/cm), (iii) use of mixed polymer solutions, and (iv) use of high concentrations of Tris-borate (TB) buffers. The DNA fragments ranging from 434 to 653 bp that were not separated using 2% PEO (8,000,000) under isocratic conditions have been completely resolved by either stepwise changes of ethidium bromide or voltage programming. Compared to PEO solutions, mixed polymer solutions prepared from PEO and HEC provide higher resolving power. Using a capillary filled with 600 mM TB buffers, pH 10.0, high-speed (< 15 min) separation of DNA (pBR 322/HaeIII digest, pBR 328/ Bg/l digest and pBR 328/Hinfl digest) has been achieved in 1.5% PEO.

In vivo magnetic resonance (MR) study of fatty liver: importance of intracellular ultrastructural alteration for MR tissue parameters change

Fatty liver is thought to have a shorter T1 relaxation time than normal liver tissue, due to the accumulation of triglyceride. Previous studies regarding T1 and T2 relaxation times, however, show widely different results. In order to elucidate the mechanism responsible for the changes and diversity of relaxation times in fatty liver, we created two animal models in 14 rabbits, one acute form (N = 6) and the other chronic form (N = 8). Four rabbits were taken as a control group. Tissue relaxation times and the magnetization transfer (MT) effect of the liver tissue in these two models were measured. The results were correlated with biochemical analysis of water and fat content and histological examination, including findings in light microscopy and electron microscopy. Although the fatty ratio in both forms of fatty liver was similar, their tissue relaxation rate and MT effect were significantly different. The acute form showed prolongation of both T1 and T2 relaxation times (512 +/- 51 msec vs. 710 +/- 95 msec and 39 +/- 1.8 msec vs. 48 +/- 3.7 msec, respectively) and a decrease of the MT effect (50 +/- 5.1% vs. 38 +/- 6.3%), compared to those of the control group and preinduction liver. The chronic form showed shorter T1 and T2 values (526 +/- 36 msec vs. 406 +/- 56 msec and 36 +/- 1.6 msec vs. 33 +/- 2.3 msec, respectively) and a stronger MT effect (21 +/- 0.9% vs. 26 +/- 2.3%). In acute form fatty liver, electron microscopic examination revealed dramatic subcellular changes, such as vesicular transformation, a markedly increased amount of smooth endoplasmic reticulum (SER), and disruption of the crista. These changes were not found in the chronic form fatty liver. From this study, we concluded that the ultrastructural alteration in the subcellular organelles of hepatocyte might play a crucial role for the chameleonic presentation of MR tissue parameters in fatty liver.

Molecular cloning and sequence analysis of canine acidic ribosomal phosphoprotein P0 cDNA

Acidic ribosomal phosphoprotein P0 has been widely used as an estradiol-independent housekeeping gene. Expression of acidic ribosomal phosphoprotein P0 in canine prostate was detected and canine specific cDNA was cloned. Total cellular RNA was isolated from normal young (5 month-old) canine prostate tissue. Total cDNAs were synthesized from total cellular RNAs by reverse transcription assay. Primers used in polymerase chain reaction were designed from published human ARP0 cDNA sequences and utilized to amplify 562 base-pair (bp) canine acidic ribosomal phosphoprotein P0 cDNA. Nucleotide sequences of canine ARP0 cDNA clones were determined on both strands. Canine ARP0 cDNA and their deduced amino acid sequences share very high homology to ARP0 orthologs from other vertebrate species including human, mouse, rat, chicken, and bovine.

Identification of two down-regulated genes in rat liver allografts by mRNA differential display

Total RNA differential display (DD) using random primers was performed for rat orthotopic liver transplantation (OLT) models. DA (RT1a) donor livers were transplanted into DA, PVG (RT1c), and LEW (RT1l) recipients: (1) syngeneic OLT (DA-DA): no rejection occurs; (2) allogeneic OLT (DA-PVG): rejection occurs, but is naturally overcome without immunosuppression; (3) allogeneic OLT (DA-LEW): animals die of acute rejection within 14 days. cDNA was isolated from selected bands, re-amplified for sequencing, and confirmed by Northern blots. Two down-regulated genes were observed in day-7 allogeneic OLT livers (DA-PVG, DA-LEW), while they were consistently expressed in day-7 syngeneic OLT (DA-DA) livers. These two genes were identified as alpha-glutathione sulfotransferase (alpha-GST) Ya gene and estrogen sulfotransferase (EST), respectively. Northern blots confirmed that their expression was down-regulated in OLT (DA-PVG) livers on days 7-26 and gradually restored. The mRNA expression of GST and EST may be good markers to predict rejection or induction of tolerance.

Modulations of Spinal Serotonin Activity Affect the Development of Morphine Tolerance

To test whether modulations of spinal serotonin (5-HT) levels would affect the development of morphine tolerance, we treated rats with either intrathecal 5-HT or 5,7-dihydroxytryptamine (5,7-DHT; a 5-HT neurotoxin) in addition to systemic infusion with morphine (2 mg x kg(-1) x h(-1)). Continuous infusion of 5-HT (10 microg x 6 microL(-1) x h(-1)) into the lumbar subarachnoid space of rats for 9 h accelerated the development of morphine tolerance. The area under the curve for the tail-flick latency test was 454.1 +/- 35.1 in the Sham Control group vs 327.6 +/- 41.0 in the 5-HT-Infused group. mu-opioid receptor binding in the lumbar spinal cord showed a decrease in the Bmax (maximal binding -46.5%), but not the binding affinity (Kd), in 5-HT-infused rats. However, intrathecal injection of 5,7-DHT (50 microg), which resulted in a 48% reduction in 5-HT and 51% reduction in 5-hydroxyindoleacetic acid concentrations, led to an attenuation of morphine tolerance (the area under the curve was 613.0 +/- 24.7 in the 5,7-DHT-Lesioned group). The binding study indicated that the affinity of lumbar micro-opioid receptors decreased 196% in 5-HT-depleted rats, whereas there was no effect on apparent binding. The infusion of 5-HT (10 microg x 6 microL(-1) x h(-1)) was not analgesic and the 5,7-DHT-induced lesion did not affect acute morphine-induced analgesia. We conclude that activity of spinal 5-HT-containing neurons plays a crucial role during the development of morphine tolerance.

Combustion modeling and performance evaluation in a full-scale rotary kiln incinerator

This work summarizes the results of numerical investigations and in situ measurements for turbulent combustion in a full-scale rotary kiln incinerator (RKI). The three-dimensional (3D) governing equations for mass, momentum, energy, and species, together with the kappa - epsilon turbulence model, are formulated and solved using a finite volume method. Volatile gases from solid waste were simulated by gaseous CH4 distributed nonuniformly along the kiln bed. The combustion process was considered to be a two-step stoichiometric reaction for primary air mixed with CH4 gas in the combustion chamber. The mixing-controlled eddy-dissipation model (EDM) was employed to predict the conversion rates of CH4, O2, CO2, and CO. The results of the prediction show that reverse flows occur near the entrance of the first combustion chamber (FCC) and the turning point at the entrance to the second combustion chamber (SCC). Temperature and species are nonuniform and are vertically stratified. Meanwhile, additional mixing in the SCC enhances postflame oxidation. A combustion efficiency of up to 99.96% can be achieved at approximately 150% excess air and 20-30% secondary air. Reasonable agreement is achieved between numerical predictions and in situ measurements.

The heterogeneity in risk factors of lung cancer and the difference of histologic distribution between genders in Taiwan

OBJECTIVE

The difference in histologic patterns of lung cancer between men and women in Taiwan may be associated with the heterogeneity in causal factors of lung cancer between the sexes. A sex- and age-matched case-control study was designed to investigate such a relationship.

METHODS

Cases consisted of 236 male and 291 female incident cases with newly diagnosed and histologically confirmed primary carcinoma of the lung, and were compared to one or two individually matched controls.

RESULTS

Cigarette smoking, occupations, and previous tuberculosis history were found to independently correlate with an elevated risk of squamous/small cell carcinoma and adenocarcinoma for male patients. However, there was little difference in the effect of these risk factors except smoking. The use of fume extractors in the kitchen, and the habit of waiting to fry after the fumes were emitted, separately explained the majority of the attributable fraction of female squamous/small cell carcinoma (28.2%) and adenocarcinoma (47.7%). With the exception of a kitchen with fume extractors and a clinical history of tuberculosis, the environmental causal factors of lung cancer were heterogeneous between these two histologic cell groups.

CONCLUSIONS

Our results suggested that the causal factors of lung cancer might be specific for the type of tumor concerned. The gender-specific risk factors of lung cancer could partly explain the difference in cell-type distribution between men and women.

Coordination exercise and postural stability in elderly people: Effect of Tai Chi Chuan

OBJECTIVE

To evaluate the effects of coordination exercise on postural stability in older individuals by Chinese shadow boxing, Tai Chi Chuan (TCC).

DESIGN

Cross-sectional study.

SETTING

Research project in a hospital-based biomechanical laboratory.

PARTICIPANTS

The TCC group (n = 25) had been practicing TCC regularly for 2 to 35 years. The control group (n = 14) included healthy and active older subjects.

INTERVENTION

Static postural stability test: progressively harder sequential tests with 6 combinations of vision (eyes open, eyes closed, sway-referenced) and support (fixed, sway-referenced); and dynamic balance test: 3 tests of weight shifting (left to right, forward-backward, multidirectional) at 3 speeds.

MAIN OUTCOME MEASURES

Static and dynamic balance of Sensory Organization Testing (SOT) of the Smart Balance Master System.

RESULTS

In static postural control, the results showed no differences between the TCC or control group in the more simple conditions, but in the more complicated SOT (eyes closed with sway surface, sway vision with sway surface), the TCC group had significantly better results than the control group. The TCC group also had significantly better results in the rhythmic forward-backward weight-shifting test. Duration of practice did not seem to affect the stability of elder people.

CONCLUSION

The elderly people who regularly practiced TCC showed better postural stability in the more challenged conditions than those who do not (eg, the condition with simultaneous disturbance of vision and proprioception). TCC as a coordination exercise may reduce the risk of a fall through maintaining the ability of posture control.

Mitomycin C with weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin in patients with biliary tract and periampullar carcinomas

We have reported a 33% partial response rate with acceptable toxicity using weekly 24-h infusion of high-dose 5-fluorouracil (5-FU) and leucovorin (LV) in patients with far advanced biliary tract cancers (BTC). In this study, we added mitomycin (MMC) to 5-FU and LV in an attempt to improve the response rate and survival. From July 1997 to September 1999, 25 chemotherapy-naive patients with pathology-proven far advanced BTC and periampullar cancers were enrolled. The regimen consisted of MMC 10 mg/m(2) every 8 weeks combined with 5-FU 2600 mg/m(2) and LV 150 mg at a schedule of 24-h infusion weekly for 6 weeks followed by a 2 week break. There were 10 males and 15 females with a median age of 57 years (range 40-76). The sites of primary tumor were 15 intrahepatic cholangiocarcinomas (CC), one perihilar CCs, three distal BTC, three gallbladder cancers (GB) and three periampullar cancers. A total of 148 sessions of chemotherapy were given with a mean of 8 (range 2-18). Nineteen patients were evaluable for response. The response rate was: 26% (five of 19) partial response, 42% (eight of 19) stable disease and 32% (six of 19) progressive disease. All of the patients were evaluable for toxicity. Toxicities more than grade III-IV were thrombocytopenia 16% (four of 25), leukopenia 12% (three of 25) and vomiting 4% (one of 25). There were four treatment-related deaths. The median time to disease progression was 3 months. The median survival was 6 months. A combination of MMC with weekly high-dose 5-FU and LV in patients with BTC did not improve the response rate, but produced more toxicity than weekly high-dose 5-FU and LV alone.

Klebsiella brain abscess in adults

BACKGROUND

We analyzed the clinical manifestations and therapeutic outcomes of Klebsiella brain abscesses.

PATIENTS AND METHODS

The clinical data of 15 patients with Klebsiella brain abscesses, retrospectively collected over a 14-year period, were studied.

RESULTS

The 15 patients included 13 cases of Klebsiella pneumoniae infection and two cases of Klebsiella oxytoca. All but one case were community-acquired infections. Locations of all of these abscesses were supratentorial. 12 cases involved a single abscess, and three involved multiple abscesses. Gas formation was also found in two cases (13%). Common predisposing factors included metastatic spread, chronic otitis media and neurosurgical procedures. Among these 15 patients, 11 were treated surgically and four received antibiotics alone. In total, 11 patients survived and four died, with an overall mortality rate of 26.7%.

CONCLUSION

The clinical presentations and therapeutic outcomes varied according to the different Klebsiella species. While debilitating diseases were common in K. pneumoniae infections, they were not common in K. oxytoca infection. And while metastatic septic abscess is a well-known, devastating complication of K. pneumoniae septicemia, usually seen as a brain abscess with a gas-forming appearance, all of these K. oxytoca infections had both otogenic infections and more favorable outcomes.

N-Acyl-1,2,3,4a,5,10b-hexahydro-[1]benzopyrano-[3,4-b][1,4]oxazine-9-carbonitriles as bladder-selective potassium channel openers

Optically active N-acyl-5,5-dimethyl-1,2,3,4a,5,10b-hexahydro-[1]benzopyrano[3,4-b][1,4]oxazine-9-carbonitriles 2-22 were synthesized as rigid analogues of cromakalim. The (4aR, 10bR)-N-benzoyl derivative (-)-11 was identified as a bladder-selective KCO (IC50, bladder = 8.2 microM, C50, portal vein = 34.5 microM). Among the analogues of 11 with substitution on the benzoyl moiety, the 3-methyl analogue (-)-14 showed highly potent and selective activity at portal vein (IC50, bladder = 279 microM, IC50, portal vein = 0.54 microM). The 4-bromo analogue (-)-19 (IC50, bladder = 2.0 microM, IC50, portal vein = 8.1 microM) and the 4-hydroxy analogue (-)-21 (IC50, bladder = 3.8 microM, IC50, portal vein = 75 microM) showed enhanced activity at the bladder, while maintaining unprecedented bladder selectivity in vitro. The N-benzenesulfonyl analogue (-)-22, a bioisoster of (-)-11, showed similar activity at the bladder with enhanced selectivity (IC50, bladder = 11.6 microM, IC50, portal vein = 120 microM).

Design, synthesis, and biological evaluation of HIV/FIV protease inhibitors incorporating a conformationally constrained macrocycle with a small P3' residue

A series of norstatine-based HIV/FIV protease inhibitors incorporating a 15-membered macrocycle as a mimic of the tripeptide (Ala-Val-Phe), a motif with a small P3' residue elective against the FIV protease and the drug-resistant HIV proteases, has been synthesized. It was found that the macrocycle is important to the overall activity of the inhibitors. Certain inhibitors were developed expressing low nanomolar inhibitory activity against the HIV/FIV proteases and they are also effective against some drug-resistant as well as TL3-resistant HIV proteases.

Intraspinal osteolipoma. Case report

Lipomatous tumors can contain uncommon or rare components (such as fibrolipoma or angiolipoma) that may result in the development of symptoms. To the best of the authors' knowledge, lipoma associated with an osseous component has not been previously reported. A case of intraspinal extradural tumor composed of both adipose and bone tissue is presented. Current theories on the cause of lipoma with an osseous component are discussed. The tumor was histologically confirmed to be an osteolipoma, and the patient recovered well after resection.

Telomere-binding and Stn1p-interacting activities are required for the essential function of Saccharomyces cerevisiae Cdc13p

Yeast Saccharomyces cerevisiae Cdc13p is the telomere-binding protein that protects telomeres and regulates telomere length. It is documented that Cdc13p binds specifically to single-stranded TG(1-3) telomeric DNA sequences and interacts with Stn1p. To localize the region for single-stranded TG(1-3) DNA binding, Cdc13p mutants were constructed by deletion mutagenesis and assayed for their binding activity. Based on in vitro electrophoretic mobility shift assay, a 243-amino-acid fragment of Cdc13p (amino acids 451-693) was sufficient to bind single-stranded TG(1-3) with specificity similar to that of the native protein. Consistent with the in vitro observation, in vivo one-hybrid analysis also indicated that this region of Cdc13p was sufficient to localize itself to telomeres. However, the telomere-binding region of Cdc13p (amino acids 451-693) was not capable of complementing the growth defects of cdc13 mutants. Instead, a region comprising the Stn1p-interacting and telomere-binding region of Cdc13p (amino acids 252-924) complemented the growth defects of cdc13 mutants. These results suggest that binding to telomeres by Cdc13p is not sufficient to account for the cell viability, interaction with Stn1p is also required. Taken together, we have defined the telomere-binding domain of Cdc13p and showed that both binding to telomeres and Stn1p by Cdc13p are required to maintain cell growth.

Production of activated carbons from pyrolysis of waste tires impregnated with potassium hydroxide

Activated carbons were produced from waste tires using a chemical activation method. The carbon production process consisted of potassium hydroxide (KOH) impregnation followed by pyrolysis in N2 at 600-900 degrees C for 0-2 hr. The activation method can produce carbons with a surface area (SA) and total pore volume as high as 470 m2/g and 0.57 cm3/g, respectively. The influence of different parameters during chemical activation, such as pyrolysis temperature, holding time, and KOH/tire ratio, on the carbon yield and the surface characteristics was explored, and the optimum preparation conditions were recommended. The pore volume of the resulting carbons generally increases with the extent of carbon gasified by KOH and its derivatives, whereas the SA increases with degree of gasification to reach a maximum value, and then decreases upon further gasification.

Sampling efficiency of a modified closed-face cassette sampler for airborne toluene diisocyanate determination

OBJECTIVES

A modified closed-face cassette was developed for sampling and derivatizing airborne toluene diisocyanate (TDI).

METHODS

The cassette was assembled as a regular two-piece cassette sampler except that the whole inner surface of the sampler was loaded with coated filters to ensure that all of the aspirated TDI react with 1-(2-pyridyl) piperazine (1-2pp).

RESULTS

A test atmosphere study showed that the sampling efficiencies were 89.4% and 94.3% for 2,4-TDI and 2,6-TDI. One-third of the 2,4-TDI and 2,6-TDI mass was constantly collected on the top and middle-rim filters. A polyurethane (PU)-manufacturing plant study revealed an average of 35% and 33% of both isomer masses collected on the top and middle-rim filters. The 2,4-TDI collection of the closed-face cassette sampling was 21% higher than that of open-face sampling. Furthermore, consistent isomeric compositions of airborne 2,4-/2,6-TDI obtained from both types of samplers validated the use of the modified cassette sampler.

CONCLUSIONS

The closed-face cassette sampler is capable of a higher collection of airborne TDI and the technique involved is as simple and feasible as that of the open-face sampler.

The effects of gossypol on the invasiveness of MAT-LyLu cells and MAT-LyLu cells from the metastasized lungs of MAT-LyLu-bearing Copenhagen rats

Recently, we isolated a novel subline of the MAT-LyLu cell line from the metastasized lungs of MAT-LyLu-bearing Copenhagen rats (MLL cells). In this study, we compared the MLL cells to the parental MAT-LyLu cells with respect to invasive ability, mRNA expression level for the nm23 metastasis suppressor gene, and response to gossypol (GP), a natural compound with documented antiproliferative and antimetastatic activity, in an in vitro invasion assay. ML cells were isolated from mechanically dissociated metastasized lungs from MAT-LuLu-bearing Copenhagen rats. Comparisons of the invasive ability and steady-state levels of nm23 mRNA between MLL and MAT-LuLu cells were determined by in vitro invasion assay and RT-PCR, respectively. The results show that MLL cells display a higher penetration percentage than MAT-LyLu cells in the in vitro invasion assay. Furthermore, RT-PCR revealed that MLL cells possess lower steady state levels of nm23 mRNA than MAT-LyLu cells, suggesting a molecular basis for the observed differences in in vitro invasive ability. Finally, both MLL and MAT-LyLu cells were susceptible to gossypol, which induced dose-dependent inhibition of invasive activity. These results report the isolation of a novel, more highly invasive subline of the MAT-LyLu cell line that is as susceptible to the inhibitory effects of gossypol as the parental MAT-LyLu cells. The MLL cells, in combination with the parental MAT-LyLu cells, can be valuable tools for investigating the biology and behavior of metastatic cells and their response to chemotherapeutic/preventive agents.

Lack of mutations of BCL6 and BCL10 genes in mucosa-associated lymphoid tissue lymphomas of the orbital adnexa

Knowledge regarding the molecular pathogenesis and progression of mucosa-associated lymphoid tissue (MALT) lymphomas of ocular adnexa is limited. Eleven cases of ocular MALT lymphoma were analyzed by clonal rearrangement of antigen receptor genes using Southern blot hybridization. Polymerase chain reaction-single stranded conformational polymorphism analysis and DNA sequencing was utilized to analyze the mutations of BCL6 and BCL10 genes. Clonal rearrangement of immunoglobulin heavy genes was found in all 11 patients. No point mutation was found in BCL6 or BCL10 genes in any of the samples analyzed. We suggest that mutations of BCL6 and BCL10 genes are rare in low-grade MALT lymphoma of ocular adnexa and are unlikely to be involved in the pathogenesis of the disease. But the role of alterations of both BCL6 and BCL10 genes in the disease progression of low-grade MALT lymphoma require additional study.

Dairy calcium is related to changes in body composition during a two-year exercise intervention in young women

OBJECTIVE

Relationships between micronutrients and dairy product intake and changes in body weight and composition over two years were investigated.

DESIGN

Two year prospective non-concurrent analysis of the effect of calcium intake on changes in body composition during a two year exercise intervention.

SUBJECTS

54 normal weight young women, 18 to 31 years of age.

MEASURES OF OUTCOME

Mean intakes of nutrients of interest were determined from three-day diet records completed at baseline and every six months for two years. The change in total body weight and body composition (assessed by dual x-ray absorptiometry) from baseline to two years was also determined.

RESULTS

Total calcium/kilocalories and vitamin A together predicted (negatively and positively, respectively) changes in body weight (R2 = 0.19) and body fat (R2 = 0.27). Further, there was an interaction of calcium and energy intake in predicting changes in body weight, such that, only at lower energy intakes, calcium intake (not adjusted for energy) predicted changes in body weight.

CONCLUSIONS

Regardless of exercise group assignment, calcium adjusted for energy intake had a negative relationship and vitamin A intake a positive relationship with two year changes in total body weight and body fat in young women aged 18 to 31 years. Thus, subjects with high calcium intake, corrected by total energy intake, and lower vitamin A intake gained less weight and body fat over two years in this randomized exercise intervention trial.

Identification of the indoleamine 2,3-dioxygenase nucleotide sequence in a rat liver transplant model

A tryptophan catabolizer, indoleamine 2,3-dioxygenase (IDO) is highly expressed in the placenta and plays an essential role in maternal tolerance. Recent data have shown that the administration of an IDO inhibitor blocked not only maternal tolerance but also liver allograft tolerance. However, little is known about the induction of IDO in liver allografts, although a gene specific for tryptophan 2,3-dioxygenase (TDO) is believed to be expressed in the liver. In the present study, we investigated whether IDO is induced in liver allografts. Synthetic oligonucleotide primers based on the mouse IDO cDNA sequence were used to amplify RNA derived from livers of donor, syngeneic or allogeneic OLT rats. RNA encoding IDO was induced in the rat allogeneic liver after orthotopic liver transplantation (OLT), but not in syngeneic OLT. The rat nucleotide sequence of the RT-PCR products obtained from OLT livers revealed identities of 89% homology to the mouse IDO and of 68% to the human IDO. This study demonstrated the presence of RNA encoding IDO in allogeneic OLT livers, which may be involved in the immune response after liver transplantation.

Fed-batch bioreactor strategies for microbial decolorization of azo dye using a Pseudomonas luteola strain

A Pseudomonas luteola strain possessing azoreductase activity was utilized to decolorize a reactive azo dye (C. I. Reactive Red 22) with fed-batch processes consisting of an aerobic cell growth stage and an anaerobic fed-batch decolorization stage. The fed-batch decolorization was conducted with different agitation and aeration rates, initial culture volumes, dye loading strategies, and yeast extract to dye (Y/D) ratios, and the effect of those operation parameters on azo dye decolorization was evaluated. Dissolved oxygen strongly inhibited the azo reduction activity; thus aeration should be avoided during decolorization but slight agitation (around 50 rpm) was needed. With the periodical feeding strategy, the specific decolorization rate (v(dye)) and overall decolorization efficiency (eta(dye)) tended to increase with increasing feeding concentrations of dye, whereas substrate inhibition seems to arise when the feeding concentration exceeded 600 mg dye/L. In the continuous feeding mode, higher initial culture volume resulted in better eta(dye) due to higher biomass loading, but lower v(dye) due to lower dye concentration in the bioreactor. With a volumetric flow rate (F) of 25 mL/h, both v(dye) and eta(dye) increased almost linearly with the increase in the loading rate of dye (F(dye)) over the range of 50-200 mg/h, while further increase in F(dye) (400 mg/h) gave rise to a decline in v(dye) and eta(dye). As the F was doubled (50 mL/h), the v(dye) and eta(dye) increased with F(dye) only for F(dye) < 80 mg/h. The best v(dye) (113.7 mg dye g cell(-)(1) h(-)(1)) and eta(dye) (86.3 mg dye L(-)(1) h(-)(1)) were achieved at F(dye) = 200 mg/h and F = 25 mL/h. The yield coefficient representing the relation between dye decolorized and yeast extract consumed was estimated as 0.8 g/g. With F(dye) = 75 mg/h, the Y/D ratio should be higher than 0.5 to ensure sufficient supply of yeast extract for stable fed-batch operations. However, performance of the fed-batch decolorization process was not appreciably improved by raising the Y/D ratio from 0.5 to 1.875 but was more sensitive to the changes in the dye loading rate.

Anxiolytic effect of seed of Ziziphus jujuba in mouse models of anxiety

The aim of the present study was to investigate the ethanolic extract of Semen Ziziphi jujuba (SZJE) induced anxiolytic effect. The SZJE was orally administered to male ICR mice, at 0.5, 1.0 and 2. 0 g/kg, 30 min before the behavioral evaluation in the black and white test (BWT) and elevated plus maze (EPM). The SZJE at the dosage 0.5-2.0 g/kg increased the first time entry, total changes and times spent in the white chamber of the BWT. The SZJE at the dosage 0.5-1.0 g/kg increased the percentage of time-spent and the percentage of arm entries in the open arms of the EPM and decreased the percentage of time-spent and the percentage of arm entries in the closed arms of the EPM. Furthermore, the SZJE at the dosage of 1. 0 g/kg prolonged the hexobarbital-induced sleeping time in mice and decreased the locomotor activity in rats. These results suggested that SZJE possessed anxiolytic effect at lower dose and sedative effect at higher dose.

Phase II study of gemcitabine in patients with advanced hepatocellular carcinoma

BACKGROUND

The objective of this study was to evaluate the efficacy and toxicity of gemcitabine in patients with chemotherapy-naïve, advanced hepatocellular carcinoma (HCC).

METHODS

Twenty-eight patients with unresectable and nonembolizable HCC who had received no prior systemic chemotherapy and with objectively measurable tumors, adequate liver and renal function, and adequate bone marrow reserve were enrolled on this study. The therapy consisted of gemcitabine 1250 mg/m(2) intravenously over 30 minutes weekly in an outpatient clinic. One course of treatment included three consecutive weekly infusions of gemcitabine and a 1-week rest. Treatment courses were repeated every 4 weeks for a total of six courses unless there was prior evidence of progressive disease.

RESULTS

All 28 patients were evaluable for response and toxicity. A partial response (PR) was achieved in 5 patients, for an overall response rate of 17.8% (95% confidence interval, 2.7-32.9%). Seven patients had stable disease (25%), and 16 patients had disease progression (57.2%). The median survival for all 28 patients was 18. 7 weeks, and, for those patients who achieved a PR, it was 34.7 weeks. The median time to progression was 12 weeks. National Cancer Institute Common Toxicity Criteria Grade 3-4 toxicity consisted primarily of leucopenia (10.7%), anemia (14.3%), thrombocytopenia (10.7%), and hepatotoxicity (14.3%). The spectrum of both hematologic and nonhematologic toxicity was mild, with thrombocytopenia constituting the dose-limiting side effect.

CONCLUSIONS

Gemcitabine shows marginal antitumor activity in patients with advanced HCC, although the response duration is short-lived. Gemcitabine seems to be particularly promising because of its low toxicity profile. Further studies in combination with other active agents are warranted.

Telomerase activity in peripheral blood for diagnosis of hepatoma

BACKGROUND

Telomerase activity may be used as a molecular marker for the detection of circulating hepatoma cells in blood of patients with hepatoma.

METHODS

Telomerase activity in peripheral blood from hepatocellular carcinoma (HCC) patients was assessed by using a highly sensitive and non-radioisotope telomerase polymerase chain reaction (PCR) ELISA. Initially, tissue telomerase activity was measured in the hepatoma and non-tumour portions by using PCR ELISA within the same specimen, to compare its sensitivity with the conventional telomeric repeat amplification protocol (TRAP) method. Second, telomerase activity was measured in the peripheral blood obtained from patients with HCC, patients with chronic liver disease and in healthy controls.

RESULTS

Of the 17 HCC patients, telomerase activity was found to be positive in 14 (82%) by using TRAP and 15 (88%) by using PCR ELISA, indicating that PCR ELISA is a reliable tool for the measurement of telomerase activity. By using the Telomerase PCR ELISA assay, telomerase activities in the peripheral blood of 20 HCC patients was 1.65 +/- 0.78 units. This was significantly greater than the results obtained for 20 chronic liver disease patients (0.43 +/- 0.36 units) and 20 healthy controls (0.39 +/- 0.14 units; P < 0.0001).When the arbitrary cut-off level was set at 0.7 units (maximum value of healthy controls + 0.1), the positive frequency of telomerase activity was 25% for chronic liver disease and 80% for HCC patients (sensitivity 80%, specificity 75%). Among the HCC patients, high telomerase activity in the peripheral blood was shown at stage III HCC with vascular invasion (2.10 +/- 0.62 units, n = 9). This was significantly higher than patients at stage II of HCC (1.28 +/- 0.72 units, n = 11, without vascular invasion; P = 0.012).

CONCLUSION

These results suggest that peripheral blood telomerase activity, which may reflect haematogenous micrometastasis, is potentially a practical diagnostic/predictive marker of HCC.

Wound healing in jellyfish striated muscle involves rapid switching between two modes of cell motility and a change in the source of regulatory calcium

Small wounds (1.2 mm in diameter) made in the sheet of myoepithelial cells forming the "swimming" muscle of the jellyfish, Polyorchis penicillatus, were closed within 10 h by epithelial cells migrating centripetally to the wound center. Some 24 to 48 h later these cells redifferentiated into fully contractile muscle cells. Labeling with bromodeoxyuridine failed to reveal any cell proliferation during this process. Phenotype switching (within 1 h) from contractile muscle cells to migratory cells did not require synthesis of new protein as shown by treatment with 40 microM cycloheximide. Excitation-contraction coupling in undamaged muscle depended on entry of Ca(2+) through voltage-gated ion channels, as shown by a block of contractility by 40 microM nitrendipine and also on calcium released from intracellular stores since caffeine (10 mM) caused a 25% reduction in contractile force. In contrast, migratory cells did not require a source of extracellular calcium since migration was unimpeded by low (1 microM) free Ca(2+) or nitrendipine. Instead, modulatory calcium was derived from intracellular stores since caffeine (10 mM) and thapsigargin (10 microM) slowed migration. This lack of dependence on calcium influx in migratory cells was further confirmed by a dramatic down-regulation in voltage-gated inward current as shown by whole-cell patch recordings.

Single-agent docetaxel in metastatic breast cancer patients pre-treated with anthracyclines and paclitaxel: partial cross-resistance between paclitaxel and docetaxel

The purpose of this study was a retrospective analysis of docetaxel in a cohort of anthracyclines and paclitaxel pretreated patients with metastatic breast cancer. From July 1998 to June 1999, 24 consecutive patients were included for this study. The regimen consisted of docetaxel 75 mg/m2 in combination with a 3-day schedule of dexamethasone every 3 weeks until disease progression or unacceptable toxicity. The median age of patients was 53 (ranged 32-67) years with a median performance status of 2. Twenty of the 24 patients (84%) had measurable disease. The median number of organs involved was 2 (range 1-4). A total of 146 cycles chemotherapy were given with a mean of 6. There was a 25% (six of 24) overall response rate including one complete response, 37.5% stable disease and 37.5% progressive disease. The major toxicity included grade 3-4 leukopenia (41.7%) and eight episodes of infection. No treatment-related death was observed. The responders included patients refractory to or resistant to prior paclitaxel treatment. The median survival and median time to disease progression was 12 and 9 months, respectively. We conclude that docetaxel has a modest activity in breast cancer patients pre-treated with anthracyclines and paclitaxel, indicating a partial cross-resistance between paclitaxel and docetaxel.

Analysis of 16S rRNA and 51-kilodalton antigen gene and transmission in mice of Ehrlichia risticii in virgulate trematodes from Elimia livescens snails in Ohio

Operculate snails (the family Pleuroceridae: Elimia livescens) were collected between June and October 1998 from a river in central Ohio where repeated cases of Potomac horse fever (PHF) have occurred. Of collected snails, consistently 50 to 80% carried a combination of cercariae and sporocysts of digenetic virgulate trematodes. The trematodes obtained from each snail were pooled and tested for Ehrlichia risticii, the agent of PHF, by nested PCR using primers specific to the 16S rRNA gene. Out of a total of 209 trematode pools, 50 pools were found to be positive by PCR. The DNA sequence of the 16S rRNA gene identified in one trematode pool was identical to that of the type strain of E. risticii, and the sequence of the gene identified in another pool differed from that of the type strain by 1 nucleotide. Comparison of the deduced amino acid sequence of the partial 51-kDa antigen gene from various sources revealed that Maryland, Ohio (except Ohio 081), and Kentucky strains are in a cluster distinct from the sequences obtained from sources in California and Oregon. Ohio 081 was shown previously by antigenic composition analysis to be distinct from other groups. However, all sequences examined were not segregated according to their sources: horse blood or infected trematodes. E. risticii was found to be transmittable from trematodes to mice and was subsequently passaged from infected mice to additional mice, as determined by PCR analysis. Our findings suggest the evolution of E. risticii in the natural reservoir in separate geographic regions and persistent infection of trematode populations with E. risticii during summer and early fall. The study also suggests that the mouse can be used to isolate E. risticii from the infected trematode.

Antisense IL-10 abrogates the inhibitory effects of IL-10 production by transfected tumor cells

Interleukin-10 (IL-10) is a pleiotropic cytokine that has a variety of downregulatory effects on immunologic and inflammatory processes. Ectopic tumor expression of IL-10 inhibited tumor growth, and local administration of antisense IL-10 significantly reversed the effects of IL-10 transfection in P815 mastocytoma. Tissue inhibitors of metalloproteinase (TIMPs) have been associated with decreased tumorigenesis and reduced metastasis, and TIMPs were increased in the region surrounding P815/IL-10 tumors and reduced in antisense IL-10-treated mice. In addition, the antisense IL-10 group had the largest tumor volume and poorest survival when compared with the P815/IL-10 control or sense groups. In summary, our data suggest that, in a mouse model, antisense IL-10 has substantive effects in reducing IL-10 translation and inhibiting IL-10-mediated TIMP upregulation, and, by doing so, allows IL-10-transfected mastocytoma to grow unchecked. Thus, ectopic tumor expression of IL-10 inhibits tumor growth, and antisense IL-10 administration in vivo reverses this protective effect.

Segregation analysis of asthma: recessive major gene component for asthma in relation to history of atopic diseases

Although asthma has a significant heritable component, the mode of inheritance remains controversial because of the complexity of the disease and the influence of environmental factors. Segregation analysis for asthma are performed with and without a history of atopic diseases (dermatitis and rhinitis) after adjusting for environmental factors. To investigate whether asthma may be inherited through a major gene with two alleles, the REGD program of the Statistical Analysis for Genetic Epidemiology (SAGE) package was conducted in 1,990 individuals from 227 families with at least one asthmatic child in a cross-sectional study of respiratory diseases in Southern Taiwan. Other covariates adjusted for included age, sex, current smoking, and environmental tobacco smoking. The hypothesis of Mendelian model and no parent-offspring transmission was rejected. However, when the variables of atopic disease and environmental factors were included in the model as covariates, the models for a two-allele gene with a recessive or codominant inheritance could not be rejected, and Akaike's Information Criterion was smaller (1,377. 13) for the recessive model than all of the other models tested, assuming a major gene with a population frequency of 0.56 +/- 0.04. However, Mendelian model without family effect was rejected. In conclusion, a history of asthma in parents is a strong risk factor for asthma in offspring. Under the assumptions of the applied segregation, at least one major gene exists that could be a gene involved also in allergy. However, the data suggest that a single locus gene explains a portion of asthma that is related to the history of atopic diseases. In addition, a polygenic/multifactorial (genetic and environmental factors) influence with a recessive component inheritance may be involved in the pathogenesis of asthma.

Phase II study of gemcitabine in patients with advanced hepatocellular carcinoma

BACKGROUND

The objective of this study was to evaluate the efficacy and toxicity of gemcitabine in patients with chemotherapy-naïve, advanced hepatocellular carcinoma (HCC).

METHODS

Twenty-eight patients with unresectable and nonembolizable HCC who had received no prior systemic chemotherapy and with objectively measurable tumors, adequate liver and renal function, and adequate bone marrow reserve were enrolled on this study. The therapy consisted of gemcitabine 1250 mg/m(2) intravenously over 30 minutes weekly in an outpatient clinic. One course of treatment included three consecutive weekly infusions of gemcitabine and a 1-week rest. Treatment courses were repeated every 4 weeks for a total of six courses unless there was prior evidence of progressive disease.

RESULTS

All 28 patients were evaluable for response and toxicity. A partial response (PR) was achieved in 5 patients, for an overall response rate of 17.8% (95% confidence interval, 2.7-32.9%). Seven patients had stable disease (25%), and 16 patients had disease progression (57.2%). The median survival for all 28 patients was 18. 7 weeks, and, for those patients who achieved a PR, it was 34.7 weeks. The median time to progression was 12 weeks. National Cancer Institute Common Toxicity Criteria Grade 3-4 toxicity consisted primarily of leucopenia (10.7%), anemia (14.3%), thrombocytopenia (10.7%), and hepatotoxicity (14.3%). The spectrum of both hematologic and nonhematologic toxicity was mild, with thrombocytopenia constituting the dose-limiting side effect.

CONCLUSIONS

Gemcitabine shows marginal antitumor activity in patients with advanced HCC, although the response duration is short-lived. Gemcitabine seems to be particularly promising because of its low toxicity profile. Further studies in combination with other active agents are warranted.

Malignant phyllodes tumor of the breast metastasizing to the pancreas: case report

Phyllodes tumor of the breast, or cystosarcoma phyllodes, is an unusual breast tumor. It is usually considered a benign lesion but may have malignant potential. Only a small proportion of malignant phyllodes tumors will metastasize. A phyllodes tumor of the breast metastasizing to the pancreas is rare. This 39-year-old female patient initially presented to us with a 5 x 4 x 2 cm tumor of a right breast. After excision of the tumor, she received another wise excision for a local recurrence of the tumor. Three years had passed when she started having hematemesis and tarry stools intermittently over a period of about one month. Clinical evaluation disclosed a huge mass with an ulcerated and bloody base over the second portion of the duodenum. A pancreatoduodenectomy was then performed. During the postoperative recovery period, a rapidly enlarging tumor of the right breast was noted. She subsequently underwent a total mastectomy of the right breast. Both the duodenal tumor and the breast tumor were found to be malignant phyllodes tumors. The rarity of this kind of patient and presentation is discussed.

Optimized combinations of abatement strategies for urban mobile sources

The maximum incremental reactivity (MIR) scale was chosen as a practical index for quantifying ozone-forming impacts. The integer linear and nonlinear programming techniques were employed as the optimization method to maximize MIR and volatile organic compound (VOC) reductions, and minimize ozone's marginal cost with varied control costs. Mobile vehicles were divided into nine categories according to the demands of decision makers and the distinctive features of local circumstance in metro-Taipei. The emission factor (EF) and vehicle kilometers traveled (VKT) of each kind of vehicle were estimated by MOBILE5B model via native parameters and questionnaires. Compressed natural gas (CNG) and inspection and maintenance (I/M) were the alternative control programs for buses and touring buses; liquefied petroleum gas (LPG), I/M, methanol, electrical vehicle (EV) were for taxis and low duty gasoline vehicles. EV, methanol, and I/M were the possible control methods for two-stroke and four-stroke engine motorcycles; I/M programs for low-duty diesel trucks, heavy-duty diesel trucks, and low-duty gasoline trucks. The results include the emission ratios of specific vehicle to all vehicles, the best combination of abated measures based on different objectives, and the marginal cost for ozone and VOC with varied control costs.