TGF-beta1 alters APC preference, polarizing islet antigen responses toward a Th2 phenotype

TGF-beta1, expressed in the pancreatic islets, protects the nonobese diabetic (NOD) mouse from insulin-dependent diabetes mellitus (IDDM). The islet antigen-specific T cell response of ins-TGF-beta1 mice relied on different antigen-presenting cells (APC) from those used by NOD T cells. T cells from NOD mice utilized B cells to present islet antigen, whereas T cells from ins-TGF-beta1 mice utilized macrophages. In addition, the islet antigen-specific T cell repertoire of ins-TGF-beta1 mice was distinct and deviated toward an IL-4-producing Th2 phenotype. When ins-TGF-beta1 mice were treated with anti-iL-4 antibody, islet antigen-specific IFNGamma-producing Th1 cells were unleashed, and the incidence of diabetes increased to the level of NOD mice. This suggests active suppression of a diabetogenic T cell response. This study describes a novel mechanism in which expression of TGF-beta1 in the context of self-antigen shifts APC preference, deviating T cell responses to a Th2 phenotype, preventing IDDM.

Decreased interleukin-2 production in Korean schizophrenic patients

BACKGROUND

It has been postulated that autoimmune process may play a role in the pathogenesis of symptoms in some schizophrenic patients. Findings of altered interleukin (IL) regulation have been regarded as additional proof that schizophrenia has an autoimmunological background.

METHODS

Sixteen patients who fulfilled DSM-IV criteria for schizophrenia and who were drug free for at least six months and the same number of age- and sex-matched controls were recruited. The severity of symptoms in schizophrenia was assessed by BPRS. Phytohemagglutinin (PHA)-stimulated production and serum level of IL-1 beta, IL-2, and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

There was a significant decrease of IL-2 production (p < .01) in schizophrenic patients and a significant increase of IL-2 serum level (p < .01). No significant difference of IL-1 beta and IL-6 was found. Some patients and controls had measurable serum level of IL-1 beta and IL-6. No significant correlation between production and serum level of IL-1 beta, -2, -6 and age, duration of illness, and BPRS score in schizophrenics was found.

CONCLUSIONS

This is the first study to describe a decrease of IL-2 production and increase of IL-2 serum level in non-Caucasian schizophrenic patients. These findings are further evidence that autoimmune process is present, regardless of ethnic origin, in some schizophrenic patients.

Korean status of alcoholics and alcohol-related health problems

Recent changes in the socioeconomic status of Korea have caused big differences in alcohol-related social and health problems. The traditional trait of drinking mild fermented beverages with nutritional side dishes and meals has shifted to drinking strongly distilled liquors without any side dishes. Moreover, the alcohol consumption per adult capita of Korea is now 8.1 liters, which parallels the level of other developed countries; it used to be 1.0 liter in 1960 and 7.0 liters in 1980, respectively. But the alcohol consumption per capita of adult males is now 18.4 liters. Consequently, the national incidence of alcohol-related diseases and accidents has rapidly increased. Korean adult males have the highest risk of the incidence of hepatoma. The rate of car accidents caused by drunken driving is about 10-fold higher than in any other developed country.

Radiation-induced muscle damage in rats after fractionated high-dose irradiation

Muscle damage in the legs of male Wistar rats after exposure to high-dose radiation was evaluated by observations of biopsied tissue made with light and transmission electron microscopy. Both legs of about 40 mature male Wistar rats were exposed to 80 Gy 6 MV X rays from a linear accelerator given in 40 fractions of 2 Gy. At intervals starting from the first day to 12 months after irradiation, serial muscle biopsies were obtained by sacrificing the rats on different days according to the experimental design. The irradiated gastrocnemius muscle displayed a progressive structural change that began immediately after the completion of the exposures. Morphological changes in irradiated muscles were characterized by hemorrhage, lymphocytic infiltration and obvious vascular destruction. Increased amounts of collagen between the muscle fibers were present even at 12 months after irradiation. There were significant changes in the number, size and structure of mitochondria in the muscle cells from the first day until 1 year after irradiation. Even 12 months after the final exposure, no recovery of muscle tissue was seen by light and transmission electron microscopy.

The effect of aqueous humor suppressants on intravitreal gas bubble duration in rabbits

PURPOSE

To evaluate the effect of topical aqueous humor suppressants on the absorption of intravitreal perfluorocarbon gases.

METHODS

Sulfur hexafluoride or perfluoropropane was injected intravitreally in five rabbits. Time to gas disappearance was measured in eyes treated with topical aqueous humor suppressants and in those not treated.

RESULTS

The mean time (+/- SD) to disappearance of 0.4 cc of sulfur hexafluoride was 5.6 +/- 0.9 days, which was prolonged by 43% to 8.0 +/- 0.7 days with topical aqueous humor suppressants (P = .009). The mean time (+/- SD) to disappearance of 0.2 cc of perfluoropropane was 18.4 +/- 1.9 days, which was prolonged by 55% to 28.6 +/- 2.7 days with topical aqueous humor suppressants (P = .009).

CONCLUSION

Aqueous suppressants prolong sulfur hexafluoride and perfluoropropane intravitreal gas bubble duration in rabbits.

Preliminary results of a new covered biliary metal stent for malignant biliary obstruction

BACKGROUND AND STUDY AIMS

The biliary stents in current use have a tendency to be blocked, so we designed a self-expandable metal stent covered with polyurethane to overcome the risk of tumor ingrowth of uncovered self-expandable metal stents. To evaluate the success and the effectiveness of the new membrane-covered self-expandable metal stent (covered modified Gianturco biliary stent), we studied patients with biliary obstruction caused by biliopancreatic carcinoma.

PATIENTS AND METHODS

We retrospectively evaluated 47 patients with malignant biliary obstruction to receive either a newly developed self-expandable metal stent covered with polyurethane (21 cases) or an uncovered metal stent (Strecker stent or Wallstent, 26 cases) by the endoscopic transpapillary route.

RESULTS

The success rate of stent insertion and drainage effect of stent showed no statistical difference in patients with a new membrane-covered self-expandable metal stent compared with those with an uncovered metal stent (90.4% vs. 88.5%, P > 0.05; and 100% vs. 95.6%, P > 0.05, respectively). The median patency of the stent was slightly prolonged in patients with a membrane-covered self-expandable metal stent, but there was no statistical difference between two groups (267 vs. 233 days, P > 0.05). The rate of early complication related to stent insertion showed no significant difference between the two groups. During the follow-up period, stent occlusion due to tumor ingrowth occurred in two patients (10.5%) in the membrane-covered, self-expandable stent group, compared with six patients (26.1%) in the uncovered metal stent group. The membrane-covered metal stent was removed successfully and a polyethylene stent was reinserted in one patient who had developed tumor overgrowth.

CONCLUSIONS

A new, membrane-covered, self-expandable metal stent has a tendency towards better long-term patency than the uncovered metal stent, and it can effectively prevent tumor ingrowth into the stent. Also it is possible to remove an occluded membrane-covered stent. However, a case-controlled study, including a larger patient number, and long-term follow-up are needed.

Thin-layer chromatography and histochemistry analyses of neutral lipids in Helisoma trivolvis infected with four species of larval trematodes

Thin-layer chromatography (TLC) and histochemistry studies were done on the neutral lipid content of the digestive gland gonad (DGG) complex of Helisoma trivolvis infected with four species of larval trematodes. Two of the species, Ribeiroia sp. and Zygocotyle lunata, contained rediae, and the two others, Spirorchis sp. and an armatae xiphidiocercaria, contained sporocysts. The DGG infected by each species had its own distinct neutral lipid profile as determined by TLC. All profiles differed from that of the uninfected DGG. Densitometric TLC studies showed some quantitative differences in free sterols in infected versus uninfected DGGs. Visual observations of the chromatograms showed that all four species caused a marked elevation in the triacylglycerol fraction in the DGG as compared with the uninfected controls. Oil Red O (ORO) histochemistry studies showed that levels of neutral lipids were increased in the DGGs of infected versus uninfected samples. These histochemistry studies showed a variable distribution of neutral fat, ranging from its absence in the cercariae of Z. lunata and the armatae xiphidiocercaria to ORO-positive droplets in the excretory system of Ribeiroia sp. Rediae and sporocysts contained ORO-positive material in the body wall and in the space between cercariae.

The clinical significance of molecular response in indolent follicular lymphomas

Most patients with follicular lymphoma (FL) achieve a complete response (CR) after treatment, but eventually most of them, particularly those with stage IV, relapse due to minimal residual disease (MRD). The t(14;18) gives rise to a rearrangement of the bcl-2 oncogene that constitutes an excellent target for detection of MRD by polymerase chain reaction (PCR). One hundred ninety-four previously untreated patients with indolent FL and detectable bcl-2 rearrangement were studied. The PCR assay was used to detect bcl-2-rearranged cells in blood and marrow before and after treatment. Molecular response rate was 37%, 53%, 56%, and 66% at 3 to 5, 6 to 8, 9 to 14, and 15 to 18 months from the start of therapy, respectively. Although molecular response was higher among clinical CRs, one third of partial responders at 3 to 5 months also achieved a molecular response. Patients who achieved a molecular response during the first year of treatment had a significantly longer failure-free survival (FFS) than those who did not (4-year FFS: 76% v 38%, respectively; P < .001). Similar results were also observed in the subset of patients in clinical CR 1 year after treatment. By multivariate analysis, beta2-microglobulin (beta2-M; P < .01), and molecular response (P < .001) were the most important variables associated with outcome. When we combined beta2-M and molecular response, three prognostic groups emerged: (1) low beta2-M and molecular responders, (2) low beta2-M and nonresponders or high beta2-M and responders, and (3) high beta2-M and nonresponders. The 4-year FFS of these 3 groups were 86%, 65%, and 23%, respectively. Finally, patients who achieved molecular response and sustained it had better FFS than those who either reverted back to PCR-positive or who never achieved molecular response. Serial PCR analysis to determine the molecular response in FL correlates well with outcome especially when combined with pretreatment beta2-M.

Unilateral peripapillary myelinated retinal nerve fibers associated with strabismus, amblyopia, and myopia

PURPOSE

To describe the association of unilateral peripapillary myelinated retinal nerve fibers with myopia, strabismus, and amblyopia and to propose a possible pathologic mechanism.

METHODS

Four patients who have the findings associated with unilateral peripapillary myelinated nerve fibers are described and reviewed.

RESULT

All patients had poor visual outcomes despite treatment with full cycloplegic refraction and appropriate patching.

CONCLUSIONS

Although the origin of this association is unknown, we believe that peripapillary myelinated nerve fibers in a unilateral myopic eye may be secondary to an imbalance between the process of myelination and the formation of the lamina cribrosa. Good results have been reported with amblyopic therapy; however, it is our experience that these patients are somewhat refractory to amblyopia therapy.

Intracranial hemorrhage associated with idiopathic thrombocytopenic purpura: report of seven patients and a meta-analysis

We present the results of a meta-analysis using clinical data obtained from seven of our patients and 24 previously reported patients with idiopathic thrombocytopenic purpura complicated by intracranial hemorrhage. Twenty-four had an intracerebral hemorrhage (ICH) and seven had a subdural hematoma (SDH). Mean age of the patients with ICH was significantly younger than those with SDH. The mortality rate of ICH associated with ITP was similar to that of spontaneous ICH. All seven patients with SDH improved without sequelae.

Association of HLA phenotype and response to interferon-alpha in patients with chronic myelogenous leukemia

Twenty to 25% of patients with chronic myelogenous leukemia (CML) treated with interferon-alpha (IFN-A) achieve a complete cytogenetic response (CCR). However, cells bearing rearrangement of BCR/ABL can still be detected many years after achieving a CCR despite the absence of clinical evidence of active disease. It has been suggested that the disease is kept in a dormant state by immune mechanisms. How this is achieved is not known, but it has been speculated that p210BCR/ABL might be presented by malignant cells through HLA molecules, thus making them the target for specific immune cell killing. Because specific peptides will be expressed in association with certain HLA molecules, different HLA phenotypes could be associated with different response rates to IFN-A. The response to IFN-A-based therapies in 239 patients with chronic phase CML was analyzed according to their HLA phenotype. One hundred and ninety-four (81%) achieved complete hematologic response, 142 (59%) had a cytogenetic response which was major (MCR) in 93 patients (39%): complete (CCR) in 71 (30%) and partial (PCR) in 22 (9%). Patients with an HLA-B27 phenotype had the best response rate to IFN-A: 10 of 14 (71%) had an MCR, including eight (57%) with a CCR (P=0.02). Patients with HLA-B35, -A3, and -A31 also showed a trend towards a higher response rate, whereas patients with HLA-B18 had the lowest response rate (MCR 17%). Patients with HLA-B27 and those with HLA-A31 showed a trend for better survival, whereas patients with HLA-A2, -B7, or -B18 had a trend for shorter survival. We conclude that response to IFN-A in patients with CML may be associated with the HLA phenotype. However, a much larger population would be required to determine if the impact of HLA phenotype on survival is independent of other clinical prognostic features. These findings could be relevant for the understanding of immune mechanisms of control of CML and possibly the design of immune therapy for this disease.

Hepatitis B vaccination and reduced risk of primary liver cancer among male adults: a cohort study in Korea

BACKGROUND

Primary liver cancer is an important health problem in Korea, where hepatitis B virus (HBV) infection is prevalent. The authors conducted a prospective cohort study to evaluate the protective effect of HBV vaccination against liver cancer in adults.

METHODS

A total of 370,285 males aged > or = 30 comprised the study population. They were clinically free of liver diseases, and had not been vaccinated against HBV at enrolment. The results of HBV surface antigen (HBsAg) and antibody to HBsAg (anti-HBs) marker positivity and those of the vaccination programme which took place during 1985 were used for the construction of the cohort. About 5% (n = 18,914) were HBsAg positive, 78,094 were anti-HBs positive, and 273,277 were negative for both. Among the candidates for HBV vaccination (n = 273,277), 35,934 (13.2%) people had been vaccinated against HBV during 1985. Cases of liver cancer were ascertained by record linkage and from medical records covering 1986-1989. A multivariate log-linear model was used to test statistical significance and to estimate relative risks (RR).

RESULTS

The total follow-up period was 1,404,566 person-years, with an average of 3 years and 10 months. A total of 302 incident cases were ascertained. The overall incidence rate of liver cancer was 21.7 per 100,000 person-years. With reference to the incidence level among the unvaccinated and uninfected, the RR of primary liver cancer among the chronically infected and that of the unvaccinated and infected was 18.1 (95% CI: 14.2-22.9) and 0.34 (95% CI: 0.19-0.60), respectively. The RR among the vaccinated group was 0.58 (95% CI: 0.31-1.09).

CONCLUSIONS

This study suggested that artificial immunization through HBV vaccination, even in adulthood, reduces the risk of liver cancer. It might also offer a practicable means of primary prevention, especially in areas with hyperendemicity of HBV infection.

TGF-beta s stimulate cell proliferation via an autocrine production of FGF-2 in corneal stromal fibroblasts

PURPOSE

Although transforming growth factor-betas (TGF-beta s) inhibit epithelial cell proliferation, these same substances stimulate cell proliferation of fibroblasts. In order to elucidate the mechanism of stimulatory activity of TGF-beta on fibroblast, the present study was performed to determine whether TGF-beta might be an indirect mitogen acting through induction of an endogenous growth factor(s) that then acts as the direct mitogen in an autocrine manner in corneal stromal fibroblasts (CSFs).

METHODS

Cell proliferation was determined either by counting cell numbers or by analyzing the incorporation of [3H]-thymidine into DNA. The synthesis of TGF-beta, TGF-beta receptors, FGF-2 and p27 was analyzed by immunoprecipitation and immunoblotting.

RESULTS

TGF-beta 1, TGF-beta 2, and TGF-beta 3 significantly stimulated cell proliferation of CSFs in a dose-dependent manner. The medium conditioned by CSFs and subsequently activated by acid-inhibited cell proliferation of corneal endothelial cells by 40%. When the acid-activated media conditioned by CSFs were immunoprecipitated with either combined anti-TGF-beta 1 and TGF-beta 2 antibodies or anti-TGF-beta 3 antibody, all three TGF-beta s, with an apparent molecular size of 25 kDa, were detected, whereas CSFs produced an 80-kDa latent form of TGF-beta 1. These cells can also express TGF-beta type II receptor and betaglycan. Interestingly, CSFs produced and secreted 18-kDa FGF-2, the synthesis of which is further stimulated by either TGF-beta 1 or TGF-beta 3, while both the neutralizing antibody to FGF-2 and the FGF-2 specific antisense oligonucleotide primers significantly inhibited the stimulatory activities of TGF-beta 1 in CSFs. The expression of p27, a negative regulator in cell cycle, was not altered by TGF-beta.

CONCLUSIONS

These findings indicate that CSFs produce both TGF-beta s and FGF-2 and that FGF-2 appears to be a direct stimulator for TGF-beta-mediated cell proliferation in CSFs.

Varicella zoster virus retrobulbar optic neuritis preceding retinitis in patients with acquired immune deficiency syndrome

OBJECTIVE

This study aimed to describe a recently recognized and rare presentation of varicella zoster virus (VZV) retrobulbar optic neuritis preceding retinitis in patients with acquired immune deficiency syndrome and to identify factors that may relate to improved visual outcome.

METHODS

Diagnosis, treatment, and clinical course are described for three eyes of two patients with this viral infection.

RESULTS

Patients had decreased vision, headache, and recent zoster dermatitis. Varicella zoster virus retrobulbar optic neuritis was diagnosed on the bases of clinical, laboratory, and electrophysiologic examination results. Profound vision loss and peripheral retinitis ensued despite intravenous antiviral treatment. Combination intravenous and intravitreous antiviral injections were administered with dramatic visual recovery.

CONCLUSIONS

Varicella zoster virus retrobulbar optic neuritis should be considered in immunocompromised patients with visual loss. Early diagnosis and aggressive combination therapy via systemic and intravitreous routes may enable return of useful vision.

Analysis of the dynamic mutation in the SCA7 gene shows marked parental effects on CAG repeat transmission

The gene for spinocerebellar ataxia 7 (SCA7) includes a transcribed, translated CAG tract that is expanded in SCA7 patients. We have determined expansions in 73 individuals from 17 SCA7 kindreds and compared them with repeat lengths of 180 unaffected individuals. Subjects with abnormal expansions comprise 59 clinically affected individuals and 14 at-risk currently unaffected individuals predicted to carry the mutation by haplotype analysis. For expanded alleles, CAG repeat length correlates with disease progression and severity and correlates inversely with age of onset. Increased repeat lengths are seen in generational transmission of the disease allele, consistent with the pattern of clinical anticipation seen in these kindreds. Repeat lengths in expanded alleles show somatic mosaicism in leukocyte DNA, suggesting that these alleles are unstable within individuals as well as between generations. Although dynamic repeat expansions from paternal transmissions are greater than those from maternal transmissions, maternal transmission of disease is more common, suggesting germline or embryonic effects of the repeat expansion.

Arginine methylation facilitates the nuclear export of hnRNP proteins

Eukaryotic mRNA processing and export is mediated by various heterogeneous nuclear ribonucleoproteins (hnRNPs). Many of these hnRNPs are methylated on arginine residues. In the yeast, Saccharomyces cerevisiae, the predominant enzyme responsible for arginine methylation is Hmt1p. Hmt1p methylates both Npl3p and Hrp1p, which are shuttling hnRNPs involved in mRNA processing and export. Here, we employ an in vivo nuclear export assay to show that arginine methylation is important for the nuclear export of these hnRNPs. Both Npl3p and Hrp1p fail to exit the nucleus in cells lacking Hmt1p, and overexpression of Hmt1p enhances Npl3p export. The export of a novel hnRNP-like protein, Hrb1p, which does not bind poly(A)+ RNA, however, is not affected by the lack of methylation. Furthermore, we find a genetic relationship between Hmt1p and cap-binding protein 80 (CBP80). Together, these findings establish that one biological role for arginine methylation is in facilitating the export of certain hnRNPs out of the nucleus.

Genomic comparisons and Shiga toxin production among Escherichia coli O157:H7 isolates from a day care center outbreak and sporadic cases in southeastern Wisconsin

Contour-clamped homogeneous electric field pulsed-field gel electrophoresis (CHEF-PFGE) was used to compare Wisconsin isolates of Escherichia coli O157:H7, including 39 isolates from a 1994 day care center outbreak, 28 isolates from 18 individuals from the surrounding geographic area with sporadic cases occurring during the 3 months before the outbreak, and 3 isolates, collected in 1995, from patients with hemolytic-uremic syndrome (HUS) who were from eastern Wisconsin counties other than those inhabited by the day care center and sporadic-case individuals. The technique of CHEF-PFGE using XbaI identified seven highly related restriction endonuclease digestion profiles (REDPs) (93 to 98% similarity) among the 39 day care center isolates and nine XbaI REDPs (63 to 93% similarity) among the 28 isolates from sporadic-case individuals, including REDP 33, which was exhibited by both day care and sporadic-case isolates. PFGE analyses of sequential E. coli O157:H7 isolates from symptomatic day care center attendees revealed that the REDPs of 25 isolates from eight patients were indistinguishable whereas the REDPs of 2 of 6 isolates from two patients differed slightly (93 to 95% similarity). The REDPs of the three isolates from 1995 HUS patients were 78 to 83% similar, with REDP 26 being exhibited by one HUS-associated isolate and an isolate from one day care attendee who did not develop HUS. The genes for both Shiga toxins I and II (stx1 and stx2, respectively) were detected in all but one isolate (sporadic case), and Shiga toxin production by the day care center isolates was not significantly different from that of the other isolates, including the three HUS-associated isolates. Analyses of E. coli O157:H7 isolates from both the day care center outbreak and sporadic cases by CHEF-PFGE permitted us to define the REDP variability of an outbreak and geographic region and demonstrated that the day care center outbreak and a HUS case in 1995 were caused by E. coli O157:H7 strains endemic to eastern Wisconsin.

A previously unidentified host protein protects retroviral DNA from autointegration

Integration of a DNA copy of the viral genome into a host chromosome is an essential step in the retrovirus life cycle. The machinery that carries out the integration reaction is a nucleoprotein complex derived from the core of the infecting virion. To successfully integrate into host DNA, the viral DNA within this complex must avoid self-destructive integration into itself, a reaction termed autointegration. We have previously shown [Lee, M. S. and Craigie, R. (1994) Proc. Natl. Acad. Sci. USA 91, 9823-9827] that viral nucleoprotein complexes isolated from Moloney murine leukemia virus-infected cells exhibit a barrier to autointegration. This autointegration barrier could be destroyed by stripping factors from the complexes and subsequently restored by incubation with a host cell extract, but not by incubation with an extract of disrupted virions. We have now used this autointegration barrier reconstitution assay to purify the host factor from uninfected NIH 3T3 fibroblasts. It is a single polypeptide of 89 aa that does not match any previously identified protein. The identity of the protein was confirmed by expressing it in Escherichia coli and demonstrating the activity of the heterologously expressed protein in the reconstitution assay.

A case of ischemic colitis associated with pheochromocytoma

A 40-year-old woman was admitted because of abdominal pain and diarrhea. She sometimes experienced paroxysmal hypertension, sweating, headache, and palpitation. Sigmoidoscopic findings showed well-demarcated diffuse mucosal edema, hyperemia, and easy touch bleeding from distal descending colon up to the splenic flexure area. Barium x-ray showed loss of haustral marking, thumb printing appearance, and diffuse luminal stenosis in the transverse, descending, and sigmoid colon. On the abdominal computed tomogram, a 3.8-cm sized well-enhanced right adrenal mass was incidentally found. Twenty-four hour urinary excretion of vanillyl mandelic acid, norepinephrine, and normetanephrine were increased. Iodine131 metaiodobenzylguanidine scan showed hot uptake on the right adrenal gland compatible with pheochromocytoma. Exploratory laparotomy was done under the impression of ischemic colitis associated with pheochromocytoma. Adrenalectomy and resection of the stenotic left colon were performed. After surgery, pain subsided, blood pressure fell gradually, blood sugar and catecholamine level became normal, and bowel habit returned to normal.

Cellular uptake profile of paclitaxel using liquid chromatography tandem mass spectrometry

A new method for studying cellular uptake has been developed. This method is based on selected reaction monitoring liquid chromatography tandem mass spectrometry analysis of preparations from cell culture. The limit of detection for paclitaxel was approximately 0.1 microM intracellular concentration. This method has been utilized to study the uptake of paclitaxel and an analog (BMS-190616) in normal and multidrug resistant (MDR) cell lines. Paclitaxel and the analog, that had been noted to overcome MDR in animal models, were incubated with normal cells (HCT116) and MDR cells (HCT116(VM)46) at therapeutic concentrations. Intracellular drug concentrations were assayed at intervals from 0 to 1.0 h. Results show that paclitaxel accumulates to a level 12 times greater and BMS-190616 to a level 5 times greater in the normal cells as compared to MDR cells suggesting that paclitaxel is more sensitive to MDR than the analog. Furthermore, the steady state level of BMS-190616 was 4 fold greater than paclitaxel in the MDR cell line suggesting that at least part of this compound's increased therapeutic effect can be attributed to processes of uptake and efflux at the cellular level. These data show that the method is rapid, sensitive and presents a unique advantage over traditional radioisotopic methods in that it can readily be employed on a range of analogs without any additional synthetic effort.

Changes in alpha wave and state anxiety during ChunDoSunBup Qi-training in trainees with open eyes

We investigated the effects of ChunDoSunBup (CDSB) Qi-training, one of the Korean popular Qi-training systems, on EEG patterns, activation coefficients and state anxiety in 13 trainees with open eyes. CDSB Qi-training procedure consists of 3 stages: sound exercise, reciting Chunmoon, which is similar to a mantra; haeng-gong, a kind of body motion; and mediation. Compared to the control state (resting state before Qi-training), subjects reported less state anxiety, their activation coefficients decreased significantly during sound exercise and meditation in the occipital regions. Mean relative power and changes of mean absolute power of alpha wave increased significantly during sound exercise and meditation in the occipital regions. These results suggest that sound exercise and meditation in ChunDoSunBup Qi-training may reduce activation of the visual cortex and influence the thalamus and other functions of the brain. These could reduce anxiety levels and modulate the psychological, neurological, and physiological functions in man.

Self-esteem and causal attributions

The relationship between self-esteem and causal attributions of success and failure in achievement-related behavior was examined among undergraduate students. An integration of a self-consistency model of causal attribution and self-enhancement theory was attempted. Self-esteem and performance outcome conditions of success and failure served as independent variables. Success and failure conditions were created via feedback regarding the participants' performance on an anagram task. The participants' attributions of six causal elements (ability, effort, immediate effort, task difficulty, luck, and mood) were categorized and combined with three causal dimensions (internal-external locus, stability, and controllability), which served as dependent variables. Participants' expectations regarding performance also served as a dependent variable. The relationship between self-esteem, expectancies of success and failure, performance, and stable causality were reported. In terms of causal dimensions, internal, stable, and controllable dimensions were explained by self-enhancement.

Diverse amino acid residues function within the type 1 peroxisomal targeting signal. Implications for the role of accessory residues upstream of the type 1 peroxisomal targeting signal

The purpose of this study was to determine whether the plant type 1 peroxisomal targeting signal (PTS1) utilizes amino acid residues that do not strictly adhere to the serine-lysine-leucine (SKL) motif (small-basic-hydrophobic residues). Selected residues were appended to the C terminus of chloramphenicol acetyltransferase (CAT) and were tested for their ability to target CAT fusion proteins to glyoxysomes in tobacco (Nicotiana tabacum L.) cv Bright Yellow 2 suspension-cultured cells. CAT was redirected from the cytosol into glyoxysomes by a wide range of residues, i.e. A/C/G/S/T-H/K/ L/N/R-I/L/M/Y. Although L and N at the -2 position (-SLL, -ANL) do not conform to the SKL motif, both functioned, but in a temporally less-efficient manner. Other SKL divergent residues, however, did not target CAT to glyoxysomes, i.e. F or P at the -3 position (-FKL, -PKL), S or T at the -2 position (-SSI, STL), or D at the -1 position (-SKD). The targeting inefficiency of CAT-ANL could be ameliorated when K was included at the -4 position (-KANL). In summary, the plant PTS1 mostly conforms to the SKL motif. For those PTS1s that possess nonconforming residue(s), other residues upstream of the PTS1 appear to function as accessory sequences that enhance the temporal efficiency of peroxisomal targeting.

The relationship between evolutionary theory and phylogenetic analysis

The relationship between phylogenetic reconstruction and evolutionary theory is reassessed. It is argued here that phylogenies, and evolutionary principles, should be analysed initially as independently from each other as possible. Only then can they be used to test one another. If the phylogenies and evolutionary principles are totally consistent with one another, this consilience of independent lines of evidence increases confidence in both. If, however, there is a conflict, then one should assess the relative support for each hypothesis, and tentatively accept the more strongly supported one. We review examples where the phylogenetic hypothesis is preferred over the evolutionary principle, and vice versa, and instances where the conflict cannot be readily resolved. Because the analyses of pattern and process must initially be kept separate, the temporal order in which they are performed is unimportant. Therefore, the widespread methodology of always proceeding from cladogram to evolutionary 'scenario' cannot be justified philosophically. Such an approach means that cladograms cannot be properly tested against evolutionary principles, and that evolutionary 'scenarios' have no independent standing. Instead, we propose the 'consilience' approach where phylogenetic and evolutionary hypotheses are formulated independently from each other and then examined for agreement.