The molecular weight dependence on the photoconductivity of poly(N-vinylcarbazole)

Poly(N-vinylcarbazole), (PNVC), was prepared, fractionated by gel permeation chromatography, and then characterized by viscometry and vapour pressure osmometry. The fractionated PNVC species with relatively narrow molecular weight distributions were successfully used to measure both their electrical dark-conductivity and photoconductivity using a surface type cell in high vacuum (ca. 10^?7 mm Hg) at room temperature. A molecular weight dependent photoconductivity was found for the fractionated PNVCs with weight average molecular weights in the range of 1,2·10³ to 2,4·10⁵. This observation is in contradiction to Epping's results who has found a molecular weight independent photoconductivity in the molecular weight range of 3·10⁵ to 7·10⁶. Our molecular weight dependence may be well understood in terms of the interrupted overlap of the π-electrons of adjacent carbazolyl groups at the terminal parts of the polymer chains, this effect being all the more stronger the smaller the molecular weight is.     

Plaque assay and primary isolation of influenza a viruses in an established line of canine kidney cells (MDCK) in the presence of trypsin

A wide variety of influenza A viruses, comprising human, equine, porcine, and avian strains, grew productively in an established line of canine kidney cells (MDCK) under an overlay medium containing trypsin, and formed well-defined plaques regardless of their prior passage history. Plaquing efficiency was comparable to the efficiency of infection in fertile eggs via allantoic route. MDCK cells have also been successfully employed for the primary isolation of influenza A virus from throat washings of patients. Parallel titration of several clinical specimens showed that the inoculation into MDCK cells followed by incubation in the presence of trypsin was an isolation procedure as sensitive as the amniotic inoculation into fertile eggs.     

Characterization of enteropathogenic and enteroaggregative Escherichia coli isolated from diarrheal outbreaks.

Virulence characteristics of diarrheal outbreak-associated Escherichia coli O55:NM, O126:NM, and O111:NM were examined. The E. coli O55:NM strains were atypical enteropathogenic E. coli (EPEC), while the E. coli O126:NM and O111:NM strains should be classified as enteroaggregative E. coli (EAggEC). The contributions of EPEC and EAggEC to the human disease burden in Japan might be significantly greater than is currently appreciated.     

Effects of drug adherence on patient outcomes to early treatment for Japanese cedar pollinosis]

Drug adherence is one of the important aspects in caring for patients with allergic rhinitis. To improve clinical efficacy of early treatment for Japanese cedar pollinosis (JCP), we evaluated the effect of drug adherence on patients' outcomes. Patients were randomly selected from 16 ENT clinical sites in Osaka and Wakayama between February 24 and March 8, 2003 (peak pollen season). Efficacy was assessed using patients' ratings of nasal and ocular symptoms and overall assessment in their condition compared with previous season ones. Costs include direct costs of the drugs used for treatment to JCP from January to February. Five hundred one patients taking early treatment were enrolled. Compared to low adherence patients, those who reported higher level of adherence significantly improved overall health condition, and achieved better symptom relief of rhinorrhea and nasal congestion. In multiple logistic regression analysis, the following factors were independent risk factors for low adherence: student (p=0.002), using OTC medications (p=0.006), and short-duration of medication (p=0.001). Low costs were also risk factor for low adherence. We conclude that taking medications for JCP for 22-28 days is the best way to enhance patients' outcomes.     

Molecular targeting for epidermal growth factor receptor expressed on breast cancer cells by human fusion protein

Recombinant human ribonuclease 1 (RNasel) was chemically linked to recombinant human epidermal growth factor (EGF). The cytotoxicity of this conjugate was assayed using MTT assay. The EGF-RNase conjugate showed dose-dependent cytotoxicity against breast and squamous cell carcinomas overexpressing the EGF receptor (EGFR). The cytotoxicity of the conjugate correlated positively with the level of EGFR expression by each cell line. These results suggest that the EGF-RNase conjugate is a more effective anticancer agent with less immunogenicity and toxicity than conventional chimeric breast cancer toxins.     

Efficacy of postoperative adjuvant therapy for stage ilia breast cancer: Futraful vs futraful+tamoxifen for er-positive patients and futraful vs futraful + adriamycin for er-negative breast cancer

A multi-center, randomized controlled collaborative study was conducted in 310 institutions located throughout Japan for 3 years and 9 months from February 1985 until October 1988 to evaluate the efficacy of post-operative adjuvant therapy for patients who had previously undergone curative surgery for treatment of Stage IIIa breast cancer. Patients with estrogen receptor-positive [ER( + )] breast cancer were treated with two types of regimens, ie, cyclophosphamide + adriamycin + fluorouracil (CAF; 2 cycles) + Futraful (FT) or CAF (2 cycles) + FT + tamoxifen (TAM), and the clinical benefit of additional use of TAM was evaluated. Of the 509 ER( + ) patients registered for the trial, 473 patients (92.9%) were eligible for evaluation. The 5-year survival rate was 77.2% for the CAF + FT group and 74.6% for the CAF + FT+TAM group, and the 5-year disease-free survival rate was 56.7% for the CAF+FT group and 59.2% for the CAF + FT + TAM group. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. Analyses by factor revealed that the 5-year disease-free rate for lymph node-negative patients in the CAF + FT + TAM group was significantly higher than that for the corresponding patients in the CAF + FT group. No differences were noted in the incidence of adverse reactions between the two treatment groups, other than an increase in LDH (the frequency of which was higher in the CAF + FT+TAM group than in the CAF + FT group). Patients with estrogen receptor-negative [ER( -)] breast cancer were treated with two types of regimens, ie, CAF + FT or CAF + FT + adriamycin (ADR), and the clinical benefit of the combined use of intermittent doses of ADR was evaluated. Of the 514 ER(-) patients registered in the trial, 478 (93.0%) were eligible for evaluation. The 5-year survival rate was 64.9% for the CAF + FT group and 63.0% for the CAF + FT + ADR group, and the 5-year disease-free survival rate was 59.2% for both CAF + FT and CAF + FT + ADR groups. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. There were no significant differences between these groups in analyses by nodal or menopausal status. The incidences of adverse reactions including anorexia, nausea/vomiting and alopecia were higher in the CAF + FT+ADR group than in the CAF + FT group.     

The increase in the intracellular Ca2+ concentration induced by mechanical stimulation is propagated via release of pyrophosphorylated nucleotides in mammary epithelial cells

Mechanical stimulation of one mammary tumor cell in culture induced an increase in its intracellular calcium concentration which spread to surrounding cells. The increase in calcium can also be induced by addition of a solution in which cultured mammary tumor cells were stimulated by repeated pipetting (solution after pipetting cells, SAPC). The activity of the SAPC was completely abolished by treatment with snake venom phosphodiesterase or pyrophosphatase. Uridine triphosphate (UTP), uridine diphosphate (UDP) and ATP (1 M each) were detected in the SAPC, whereas 5-UMP and 5-AMP were produced by phosphodiesterase digestion. A mixture of UTP, UDP and ATP (1 M each) elicited a calcium response which was comparable to that induced by SAPC, while UTP, UDP or ATP alone at 1 M elicited a small increase in calcium concentration in mammary tumor cells. Suramin, a competitive antagonist of P₂ purinoceptors, diminished the spreading of the calcium wave induced by mechanical stimulation. It also blocked the responses to SAPC, UTP, UDP and ATP. These findings suggest that the mechanical stimulation results in the release of UTP, UDP and ATP into the extracellular space which mediates induction of the spreading calcium response via P_2U-type purinoceptors.     

Immune response to "self" lens in Xenopus laevis enucleated during larval life

We have reinvestigated an important issue in the amphibian immunology that has not been settled for years since the pioneer work of Triplett, concerning the necessity of being exposed to organ-specific antigens early in development. It was found that syngeneic Lenses were rejected by frogs, Xenopus laevis, that had been enucleated (eye removed) during early larval life. This rejection did not occur in intact frogs or in those enucleated in later larval or adult life. Whereas the splenocytes from intact frogs did not proliferate in response to a co-cultured syngeneic lens, those from frogs that had been enucleated at any of the larval stages, or even after metamorphosis, proliferated intensely. Both of these responses were shown to be thymus-dependent. In conclusion, it was demonstrated that the frog immune system rejected even syngeneic lenses by enucleation in early larval life and that it began to recognize the syngeneic lenses by lymphoid proliferation after enucleation, even in later life.     

Serum cytosolic beta-glucosidase elevation and early ischemic injury to guinea pig small intestine

BACKGROUND: The lack of an early, sensitive marker for intestinal ischemia has led to delay in diagnosis and worsended outcome for patients with acute onset of this condition. Our preliminary studies revealed that guinea pig cytosolic beta-glucosidase (CBG) is expressed predominantly in the small intestine, with lower levels in the liver and pancreas and undetectable levels in other organs. Cytosolic beta-glucosidase was investigated as a serum marker of small intestinal ischemia in a guinea pig model. METHODS: Guinea pigs underwent anesthesia, sham laparotomy, 30 minutes of mesenteric ischemia followed by 6 hours of reperfusion 6 hours of sustained mesenteric ischemia, or closed-loop small bowel obstruction. Serum samples were assayed for CBG activity. At the conclusion of the ischemia/reperfusion experiments, small bowel samples were assayed for residual enzyme activity, and paraffin sections were graded for the severity of histologic injury. RESULTS: Serum CBG activity rose rapidly after intestinal ischemia with and without reperfusion. Peak enzyme activities were elevated 23-fold for reperfused animals (P < .001) by 4 hours. For nonreperfused animals, peak serum CBG activities reached 29-fold above baseline and were significantly higher than the CBG activities of reperfused animals at 4 hours (P < .01) and at 6 hours (P < .05). Mucosal injury ranged from undetectable to moderate and corresponded in severity with both peak serum enzyme activity and decreased residual activity in the small bowel. In animals subjected to closed-loop obstruction, there was a mean increase of serum CBG of 9.2-fold from 4 to 6 hours after establishment of obstruction (P < .05). CONCLUSIONS: In the guinea pig model, CBG is a sensitive marker of ischemic injury caused by arterial occlusion or closed-loop obstruction of the small bowel.