Prognostic value of preoperative serum immunosuppressive acidic protein in patients with esophageal squamous cell carcinoma

Immunosuppressive acidic protein (IAP) is a potent biological marker of immunological surveillance in patients with malignant tumors. The aim of this study was to analyze the clinicopathologic significance of IAP in patients with esophageal carcinoma. Preoperative serum IAP concentration was measured by enzyme-linked immunosorbent assay in 115 patients with primary esophageal squamous cell carcinomas. The associations between clinicopathologic factors, C-reactive protein (CRP) values and IAP concentration were determined. Prognostic values were determined by multivariate analysis using Cox's proportional hazards model. The IAP concentration is significantly higher in patients with stage II-IV cancers than in those with stage I cancer. Significant differences in IAP concentration were observed depending upon tumor size, tumor depth, lymph node status and CRP values. A high IAP concentration, more than 500 micro g/mL, was an independent prognostic factor. Thus, a high IAP concentration is associated with tumor progression and poor survival in patients with esophageal squamous cell carcinoma.

Activation of cell proliferation by brassinolide application in tobacco BY-2 cells: effects of brassinolide on cell multiplication, cell-cycle-related gene expression, and organellar DNA contents

Brassinosteroids (BRs) are steroidal phytohormones that are essential for many processes in plant growth and development, such as cell expansion, vascular differentiation, and responses to stress. The effects of BRs on cell division are unclear, as attested by contradictory published results. To determine the effect of BRs on cell division, the tobacco (Nicotiana tabacum) BY-2 cell line, which is a widely-used model system in plant cell biology, was used. It was found that brassinolide (BL) promoted cell division only during the early phase of culture and in the absence of auxin (2,4-D). This promotion of cell division was confirmed by RNA gel blot analyses using cell-cycle-related gene probes. At later stages in the culturing periods of BL-supplied and 2,4-D-supplied BY-2 cells, differences in cell multiplication and cell-cycle-related gene expression were observed. Moreover, the BL-treated BY-2 cells had morphological differences from the 2,4-D-treated cells. To determine whether suppressed organellar DNA replication limited this promotion of cell division during the early culture phase, this replication was examined and it was found that BL treatment had no effect on activating organellar (plastid- and mitochondrial-) DNA synthesis. As preferential organellar DNA synthesis, which is activated by 2,4-D, is necessary during successive cell divisions in BY-2 cells, these data suggest that the mechanism of the promotion of cell division by BL treatment is distinct from that regulated by the balance of auxin and cytokinin.

The division of pleomorphic plastids with multiple FtsZ rings in tobacco BY-2 cells

Plastids, an essential group of plant cellular organelles, proliferate by division to maintain continuity through cell lineages in plants. In recent years, it was revealed that the bacterial cell division protein FtsZ is encoded in the nuclear genome of plant cells, and plays a major role in the plastid division process forming a ring along the center of plastids. Although the best-characterized type of plastid division so far is the division with a single FtsZ ring at the plastid midpoint, it was recently reported that in some plant organs and tissues, plastids are pleomorphic and form multiple FtsZ rings. However, the pleomorphic plastid division mechanism, such as the formation of multiple FtsZ rings, the constriction of plastids and the behavior of plastid (pt) nucleoids, remains totally unclear. To elucidate these points, we used the cultured cell line, tobacco (Nicotiana tabacum L.) Bright Yellow-2, in which plastids are pleomorphic and show dynamic morphological changes during culture. As a result, it was revealed that as the plastid elongates from an ellipsoid shape to a string shape after medium renewal, FtsZ rings are multiplied almost orderly and perpendicularly to the long axis of plastids. Active DNA synthesis of pt nucleoids is induced by medium transfer, and the division and the distribution of pt nucleoids occur along with plastid elongation. Although it was thought that the plastid divides with simultaneous multiple constrictions at all the FtsZ ring sites, giving rise to many small plastids, we found that the plastids generally divide constricting at only one FtsZ ring site. Moreover, using electron microscopy, we revealed that plastid-dividing (PD) rings are observed only at the constriction site, and not at swollen regions. These results indicate that in the pleomorphic plastid division with multiple FtsZ rings, the formation of PD rings occurs at a limited FtsZ ring site for one division. Multiplied FtsZ rings seem to localize in advance at the expected sites of division, and the formation of a PD ring at each FtsZ ring site occurs in a certain order, not simultaneously. Based on these results, a novel model for the pleomorphic plastid division with multiple FtsZ rings is proposed.

Amyloplast formation in cultured tobacco BY-2 cells requires a high cytokinin content

When cytokinin-autonomous tobacco BY-2 cell cultures are transferred into 2,4-dichlorophenoxyacetic acid (2,4-D)-deprived medium, amyloplast development is initiated. Using this in vitro amyloplast-inducing system, the role of cytokinins in amyloplast formation was investigated. We show that addition of lovastatin, an inhibitor of mevalonate synthesis, to amyloplast-inducing medium reduced starch accumulation. Microscopic observation also revealed that lovastatin treatment decreased starch deposition; however, the overall morphologies of cells and plastids were less affected than control cell cultures. In addition, lovastatin lowered the transcription level of the ADP-glucose pyrophosphorylase small subunit (AgpS) gene. Application of mevalonate or zeatin dramatically restored the decrease in starch deposition, and restored AgpS mRNA accumulation. Moreover, addition of other molecules with cytokinin activity, such as adenine- and phenylurea-type compounds, restored starch accumulation and AgpS transcript levels, whereas other isopentenyl pyrophosphate-derived phytohormones did not. Liquid chromatography-mass spectrometry/mass spectrometry quantification of endogenous cytokinins revealed that endogenous cytokinins increased when BY-2 cells were transferred into 2,4-D-deprived medium from conventional medium containing 2,4-D. In addition, lovastatin treatment decreased endogenous cytokinins to some extent when cultured under 2,4-D-deprived conditions. Our results suggest that both 2,4-D deprivation and an increase in endogenous cytokinins have important roles in accelerating the changes in plastid morphology, starch accumulation, and AgpS gene expression.

Isolation and expression of a novel starch-storing cell-specific gene containing the KH RNA binding domain from tobacco-cultured cells BY-2

In cultured Bright Yellow-2 tobacco (Nicotiana tabacum) cells, the depletion of 2,4-dichlorophenoxyacetic acid (2,4-D) in the culture medium induces amyloplast development. This differentiation also includes a decrease in cell multiplication, and an increase in cell size. These changes were primarily triggered by the depletion of 2,4-D, and accelerated by the addition of benzyladenine (BA). Three cDNAs were identified whose transcript levels are specifically increased during differentiation of starch-storing cells using the differential display method, and designated as starch-storing cell induced genes (SCI genes). One of these cDNAs, SCI2 encodes a 285 amino acids long protein with a KH RNA-binding domain. A database search revealed that this protein showed similarity to respective domains of mammalian quaking proteins. 2,4-D addition, which can convert starch-storing cells into dividing cells, to starch-storing BY-2 cells, immediately decreases the SCI2 transcript level, suggesting that SCI2 may have some role in starch-storing cell differentiation in BY-2 cells.

Distribution of interstitial telomere-like repeats and their adjacent sequences in a dioecious plant, Silene latifolia

The dioecious plant Silene latifolia has large, heteromorphic X and Y sex chromosomes that are thought to be derived from rearrangements of autosomes. To reveal the origin of the sex chromosomes in S. latifolia, we isolated and characterized telomere-homologous sequences from intra-chromosomal regions (interstitial telomere-like repeats; ITRs) and ITR-adjacent sequences (IASs). Nine genomic DNA fragments with degenerate 84- to 175-bp ITRs were isolated from a genomic library and total genome of male plants. Comparing the nucleotide sequences, the IASs of the nine ITRs were classified into seven elements (IAS-a, IAS-b, IAS-c, IAS-d, IAS-e, IAS-f, and IAS-g) by sequence similarity. The ITRs were grouped into two classes (class-I and -II ITRs) according to the classification of IASs. The class-I ITRs were sub-grouped into three subclasses (subclasses-IA, -IB, and -IC ITRs) based on the arrangement of IAS elements. By contrast, the class-II ITR was located between two different IASs (IAS-f and IAS-g). Genomic Southern analyses showed that both the male and female genomes contained six (IAS-f) to 153 (IAS-d) copies of each IAS per haploid genome. Fluorescence in situ hybridization analyses showed that one IAS element, IAS-d, was distributed in the interstitial and proximal regions of the sex chromosomes of S. latifolia. The distribution of IAS-d is important evidence for past telomere-mediated chromosome rearrangements during the evolution of the sex chromosomes of S. latifolia.

Effects of the concomitant administration of tamsulosin (0.8 mg) on the pharmacokinetic and safety profile of intravenous digoxin (Lanoxin) in normal healthy subjects: a placebo-controlled evaluation

A 20-day, nonrandomized, open-label, placebo-controlled study was performed to investigate whether concomitant administration of tamsulosin (0.8 mg) affects the pharmacokinetic and safety profile of intravenous digoxin (0.5 mg) in healthy subjects. Ten healthy subjects aged 21-39 years received a single oral dose of placebo on study days 1-8 and tamsulosin on days 9-18. Tamsulosin was initiated at 0.4 mg/day and the dose was increased to 0.8 mg/day from day 11. On days 2 and 15, subjects received a single intravenous dose of digoxin (0.5 mg). Safety monitoring was carried out throughout the study. Following digoxin administration, blood was drawn and urine collected over a 96-h period for pharmacokinetic determinations. Plasma tamsulosin concentrations were measured at regular intervals after dosing on day 15. The digoxin pharmacokinetic parameters with and without concomitant tamsulosin were compared. No significant difference was observed, and no irregularity was found in the plasma tamsulosin concentration data. Six subjects experienced adverse events while receiving placebo and seven while on tamsulosin. The most frequent adverse event was mild dizziness reported by four subjects. Moderate chest pain was reported in two subjects, but this was not considered to be related to the administration of the study medications. Some significant changes in vital signs were observed; however, none was accompanied by symptoms of medical concern. These changes were not temporally related to the administration of study drugs. Thus, concurrent administration of digoxin with tamsulosin did not produce any change in the pharmacokinetics of digoxin and the safety profile was acceptable. As reflected in the prescribing information for tamsulosin, no adjustment in tamsulosin dosing is required when it is administered concomitantly with digoxin.

Effects of the concomitant administration of tamsulosin (0.8 mg/day) on the pharmacokinetic and safety profile of theophylline (5 mg/kg): a placebo-controlled evaluation

We performed a single-blind, sequential-design study to investigate the effects of concomitant oral tamsulosin 0.8 mg/day on the pharmacokinetics and safety of intravenous theophylline 5 mg/kg in healthy subjects. Ten healthy volunteers aged 19-39 years received placebo on study days 0, 1, 2 and 10 and tamsulosin on days 3-9. Theophylline was administered intravenously on days 1 and 9. Theophylline and tamsulosin pharmacokinetic data were determined following administration of the drugs on days 1 and 9 and day 9, respectively. No differences were observed in theophylline pharmacokinetic parameters with and without concomitant tamsulosin, and there were no abnormalities in tamsulosin pharmacokinetic data. Some significant changes in vital signs and a number of mild adverse reactions were reported, but the overall safety profile of tamsulosin and theophylline was acceptable. The results of the study suggest that no dose adjustment in tamsulosin is necessary when it is administered concomitantly with theophylline.

[Breast cancer]

Neoadjuvant chemotherapy (NAC) represents a new approach based on sound theoretical, pharmacokinetic, and experimental principles. The purpose of NAC is to improve control of the primary site by downstaging and to improve control of micrometastatic disease. NAC has been standard therapy in the management of locally advanced breast cancer. Patients with earlier stage breast cancer may also benefit from treatment with NAC. Recently some investigators have mentioned that NAC can be used instead of adjuvant chemotherapy and would be most appropriate for patients who wish to preserve their breast but who have tumors too large for breast conserving surgery. In this article, we reviewed the present status of NAC (indication, clinical response, pathologic response, survival, possibility of breast conservation, prognostic/predictive factors, neoadjuvant endocrine therapy) and discussed several unanswered questions on NAC (survival benefit, optimal number of treatment cycles, optimal regimens) and future direction. Combined modality therapy including NAC appears to provide excellent local control, the possibility of breast conservation, and, probably, an increased survival rate, at least for some subsets of patients. Furthermore, through sequential sampling, NAC provides indeed the opportunity to identify molecular mechanisms associated with pathologic response and to study the possibility to guide the choice for induction treatment and patient populations submitted to neoadjuvant chemotherapy.

Spontaneous reduction in Epstein-Barr virus (EBV) DNA copy number in EBV-infected epithelial cell lines

We found that spontaneous and 12-0-tetradecanoylphorbol-13-acetate-induced Epstein-Barr virus (EBV) reactivation occurred in short-term (ST)-cultured EBV-infected epithelial cell lines GT38 and GT39 after their establishment; however, it diminished in the long-term (LT)-cultured cells passaged for more than 2 years from ST-cultured cells. We hypothesized that the EBV reactivation may be related to the EBV DNA copy number in the cells. A higher level of EBV DNA content was detected in ST-cultured cells than in LT-cultured cells by Southern hybridization using an EBV DNA XhoI probe. Fluorescence in situ hybridization using EBV DNA BamHI W fragments showed that ST-cultured cells contained a higher EBV DNA copy number than that of LT-cultured cells. EBV DNA-negative cells were detected in small proportions in LT-cultured cells, but were undetected in ST-cultured cells. These results demonstrate that EBV genomes are not maintained stably in the cell lines, and some of them are lost in continuous passages of the cells. We discuss the mechanisms of reduction of EBV reactivation and EBV DNA in the cell lines.

[Effect of different concentrations of tranilast on posterior capsule opacification]

PURPOSE

To evaluate the effect of different concentrations(0.5, 1.0, 2.0%) of tranilast eyedrops in preventing fibrous posterior capsule opacification (PCO) in rabbits.

METHODS

Experimental phacoemulsification procedures and in-the-bag placement of intraocular lens(IOL) implant were performed. An anterior eye segment analysis system(EAS-1000, Nidek Co, Ltd) was used to evaluate the degree of PCO during 5 weeks after surgery.

RESULTS

The development of PCO was significantly suppressed in the eyes treated with tranilast eyedrops from 1 week after surgery. The mean PCO density after treatment with 0.5% tranilast was 59.1 +/- 9.3 (mean deviation +/- standard error) and 57.1 +/- 8.2, while for 1.0% tranilast it was 40.1 +/- 6.8 and 46.6 +/- 8.4, and for 2.0% tranilast it was 38.5 +/- 6.0 and 37.5 +/- 5.6 (computer compatible tape, CCT) at 1 week and 5 weeks, respectively. In the control group, the mean PCO density was 89.3 +/- 10.4 and 137.4 +/- 32.8 at 1 week and 5 weeks, respectively(p < 0.05). However, no significant statistical difference was observed in any of the findings for the 3 different tranilast concentrations.

CONCLUSION

These results suggest that the 0.5% tranilast eyedrops, which are already available on the market, are sufficiently effective for inhibiting PCO.

[Indications for surgery for morbid obesity and effectiveness of bariatric surgery]

In this paper we describe a history and technical aspects of bariatric surgery. And surgical techniques of Divided Vertical Banded Gastroplasty and perioperative management are presented. Our indications for surgery for morbid obesity are almost equal to the guidelines for obesity surgery adopted by the American Society for Bariatric Surgery October 1986. From 1982 to 2000, 64 bariatric surgical procedures were performed at the author's institution. Vertical banded gastroplasty was performed in 45 patients, Horizontal gastric partitioning in 8 patients, Gastric bypass in 10 patients, and Divided vertical banded gastroplasty in 1 patient. The average weight loss one year after Vertical banded gastroplasty is 1/3 of the patient weight. Most of the preexisting comorbid conditions related to the obesity showed improvement or were completely resolved after surgery. No major complications were observed postoperatively. We concluded that surgical procedures for morbid obesity are very effective therapy.

Differential effect of TPA on cell growth and Epstein-Barr virus reactivation in epithelial cell lines derived from gastric tissues and B cell line Raji

We characterized the cell growth and Epstein-Barr virus (EBV) reactivation for EBV infected epithelial cell lines, GT38, GT39, and GTC-4 using 12-O-tetradecanoylphorbol-13-acetate (TPA). These cell lines grew similarly in liquid medium, and formed colonies in soft agar. The cell growth was inhibited with TPA, dose-dependently in liquid medium. The colony formation was enhanced with low concentrations of TPA, but was inhibited with high concentrations. The latent EBV was reactivated with high concentrations of TPA as shown by the expression of EBV BZLF1 gene product ZEBRA. The effects of TPA on GTC-4 were compared with a Burkitt's lymphoma cell line Raji. The mode of actions of TPA in GTC-4 was different from Raji in terms of cell growth and EBV reactivation. The effective concentrations of TPA for cell growth inhibition and EBV reactivation were higher in Raji than GTC-4. Cell cycle analysis showed that TPA (20 ng/ml) induced cell cycle arrest to Raji but not to GTC-4; however, the rate of trypan blue stained cells increased in the TPA treated GTC-4 but not Raji. These results demonstrated that TPA affects differentially for the stimulation and inhibition of cell growth, and also EBV reactivation depends on TPA concentrations and cell types.

The complete DNA sequence of the mitochondrial genome of Physarum polycephalum

The complete sequence of the mitochondrial DNA (mtDNA) of the true slime mold Physarun polycephalum has been determined. The mtDNA is a circular 62,862-bp molecule with an A+T content of 74.1%. A search with the program BLAST X identified the protein-coding regions. The mitochondrial genome of P. polycephalum was predicted to contain genes coding for 12 known proteins [for three cytochrome c oxidase subunits, apocytochrome b, two F1Fo-ATPase subunits, five NADH dehydrogenase (nad) subunits, and one ribosomal protein], two rRNA genes, and five tRNA genes. However, the predicted ORFs are not all in the same frame, because mitochondrial RNA in P. polycephalum undergoes RNA editing to produce functional RNAs. The nucleotide sequence of an nad7 cDNA showed that 51 nucleotides were inserted at 46 sites in the mRNA. No guide RNA-like sequences were observed in the mtDNA of P. polycephalum. Comparison with reported Physarum mtDNA sequences suggested that sites of RNA editing vary among strains. In the Physarum mtDNA, 20 ORFs of over 300 nucleotides were found and ORFs 14 19 are transcribed.

Tumorigenesis of Epstein-Barr virus-positive epithelial cell lines derived from gastric tissues in the SCID mouse

To study the tumorigenesis of Epstein-Barr virus (EBV)-positive epithelial cell lines GT38 and GT39 derived from human gastric tissues, we inoculated these cells under the skin of severe combined immunodeficient (SCID) mice. The development of tumors was observed in each of the mice about 2 months after the inoculation. The tumors were diagnosed with undifferentiated carcinoma by hematoxylin/eosin staining. EBV-encoded small RNA1 was detected in the paraffin-embedded tumor sections. The tumor cells had human chromosome. The circular, but not linear, EBV DNA was detected in the tumors. The molecular sizes of EBV DNA termini were the same as that of the inoculated GT38 or GT39 cells. The expressions of EBV nuclear antigen 2 and latent membrane protein 1 reduced in the tumors. Transcripts of BamHI C and W promoters in latency III were detected in the tumors and the cultured cells in vitro. The tumor cells were passaged from one SCID mouse to other SCID mice and to cultures in vitro. This is the first evidence that the EBV-positive epithelial cell lines produced tumors in the SCID mouse.

Clinical benefits of steroid therapy on surgical stress in patients with esophageal cancer

BACKGROUND

Despite improvements in surgical techniques and perioperative care, severe complications lead to long hospital stays for some esophageal cancer patients. The purpose of this study was to evaluate the safety and effectiveness of perioperative steroid therapy on the postoperative clinical course.

METHODS

Fifty-seven patients operated for esophageal cancer in 1997 and 1998 were treated with perioperative steroid therapy. Fifty consecutive patients operated in 1995 and 1996 served as a control group. In the steroid group, each patient was given 250 mg of methylprednisolone intravenously before operation followed by 125 mg on postoperative days 1 and 2. Serum interleukin-6, polymorphonuclear cell elastase, and C-reactive protein levels, and the postoperative clinical course were compared between the groups.

RESULTS

Morbidity rates including hyperbilirubinemia, anastomotic leakage, and liver dysfunction were significantly lower in the steroid group than in the control group. Days until extubation and hospital stay were significantly shorter for the steroid group. Inflammatory mediators, body temperature, heart rate, and respiratory index after the surgical procedure were significantly lower in the steroid group. Adverse effects possibly caused by steroid therapy were not observed.

CONCLUSIONS

Perioperative steroid therapy was safe and effective for the inhibition of inflammatory mediators and the improvement of the postoperative clinical course of patients with esophageal cancer.

[A case of acute type adult T cell leukemia and human T-lymphotropic virus type I associated myelopathy who presented meningitis and polyradiculoneuropathy and improved with steroid treatment]

We reported a 35-year-old male patient with acute type adult T cell leukemia(ATL) and human T-lymphotropic virus type I associated myelopathy. He presented meningitis and polyradiculoneuropathy and improved with steroid treatment. He presented headache and sensory ataxia and these symptoms responded to steroid treatment. The usual clinical features of ATL were absent at onset. There existed ATL-like cells in the cerebrospinal fluid and HTLV-I proviral DNA in the blood. Therefore, we surmised that there was monoclonal hyperplasia of the infected cells. He presented ATL after 2 years remission. We pointed out that there was acute type of ATL in patients with meningitis and polyradiculoneuropathy, for which steroid treatment could be effective.

[Pure sensory stroke due to a pontine lesion: a study of clinical symptomatology and somatosensory evoked potential findings]

We studied clinical symptomatology and somatosensory evoked potentials(SEP) of 7 pure sensory stroke patients due to pontine lesions. Clinical symptoms were examined by modality(pinprick, touch, vibration and joint position sense), intensity and distribution of the sensory disturbance. SEP were recorded by the median nerve stimulation in the upper extremities, and the posterior tibial nerve stimulation in the lower extremities. Patients 1-4 were characterized by decreased contra-lesional fingers or fingers, toes joint position sense, normal pinprick and vibration sense. We think that these patients' lesions were localized in the lemniscus medialis. Patients 5-7 were characterized by decreased contra-lesional upper extremity or upper and lower extremity vibration sense, decreased pinprick sense and normal joint position sense. We think that these patients' lesions involved spinothalamic tract. There was no abnormal finding of SEP with upper extremity stimulation, but disappearance or very low amplitude of P38 with lower extremity stimulation in 4 of the 7 patients. We conclude that 1) the vibration sense may be conducted also through the spinothalamic tract, 2) SEP findings are abnormal only with lower extremity stimulation in pontine pure sensory infarction.

[Problems in measurement of forced vital capacity--quality assessment with extrapolated volume]

In 1994, the American Thoracic Society proposed criteria for the start of expiration, middle of expiration and end of expiration in order to improve the accuracy of forced vital capacity measurement. Extrapolated volume (EV) and percent extrapolated volume (%EV), which serve as the criteria for the start of expiration, were studied in this paper. It was demonstrated that the values of %V50 and %FEV1.0% increased incorrectly when EV or %EV were outside the criteria because of an erroneous start point for expiration or poor technique. Similar results were obtained in the same subjects, who underwent FVC measurement more than twice with different effort levels. The present study demonstrated that obstructive ventilatory impairment may be underestimated if EV or %EV is outside the criteria. We concluded that the values of EV and %EV are parameters which indicate a rapid rise of the internal pressure of the thoracic cavity at the start of expiration and should be considered in seeking correct measurement of respiratory function including FVC.

Comparison of the effects of zolpidem and zopiclone on nocturnal sleep and sleep latency in the morning: a cross-over study in healthy young volunteers

Zolpidem (ZOL) and zopiclone (ZPC) are non-benzodiazepine hypnotics, with unique effects on sleep architecture compared with conventional benzodiazepines. The two compounds have different profiles in action to two major subtypes of the GABA-A receptors, therefore different effects on sleep structure may be expected. In the present study, the effects of ZOL (10mg) and ZPC (7.5mg) were compared in nine healthy young male subjects during nine-night sessions, employing a crossover design. Time courses during the sessions were significantly different between the compounds in the ratio (%) of S2 and S1. Compared to the baseline, an increase of S2 and a decrease of S1 and SR were caused by ZPC, not by ZOL. SWS was increased by both ZPC and ZOL. Significant changes by ZOL were found during the first 150-min, while changes by ZPC were mostly observed during the second 150-min. This might be related to their half-lives. ZOL did not affect sleep latency in the morning, while ZPC caused a significant decrease. Subjective sleepiness, however, was not increased in the ZPC or ZOL mornings. It was speculated that difference in the action to the GABA-A receptor subtypes might be related to the differences in the effects on the sleep architecture between the compounds.

[Measures for the disposal of non-regulated alternative medical wastes--effects of disinfectants on activated sludges]

Effects on activated sludges of several disinfectants with strong and wide antimicrobial ability, were investigated using an oxygen up-take method. As a results, at the maximal non-reactive concentration of disinfectants, hexachlorophene has estimated value of 6 mg/l and shows the highest toxicity against activated sludges. At the lethal concentration of 50%, the toxicity of triclosan is the strongest disinfectant.

Radiosensitivity of human breast cancer cells transduced with wild-type p53 gene is influenced by the p53 status of parental cells

Induction of apoptosis with chemotherapeutic agents or radiation in tumours is frequently related to the status of those p53 gene of the tumours. To examine whether forced expression of the wild-type p53 gene in tumour cells can modulate their susceptibility to radiation and anti-cancer agents, we retrovirally transduced two types of human breast cancer cell lines, which respectively harboured a mutated p53 gene (OCUB-M) or wild-type p53 gene (YMB-1), with the wild-type p53 gene. Transduced cells which consistently expressed the wild-type p53 gene (OCUB-M/p53, YMB-1/p53) proliferated at the same rate as control cells which were transduced with the beta-galactosidase gene (OCUB-M/lacz, YMB-1/lacz). However, sensitivity to radiation was increased in OCUB-M/p53 cells but not in YMB-1/p53 cells. In vitro chemosensitivity to DNA-damaging anticancer agents such as cyclophosphamide and 5-fluorouracil was not influenced by the transduction of the wild-type p53 gene in either cells. Expression of the wild-type p53 gene in p53-mutated human breast cancer cells can therefore increase their sensitivity to radiation but not their chemosensitivity. Therapeutic effects following by the transduction of the wild-type p53 gene were not observed in breast cancer cells already bearing the wild-type p53 gene.