Effects of radiotherapy on the cellular uptake of carbon-14 labeled L-methionine in tumor tissue

In order to examine in vivo effects of irradiation on tumor uptake of L-[methyl-11C]methionine at a cellular level, the distribution of L-[methyl-14C]methionine (Met) in a rat AH109A tumor model was investigated using microautoradiography. Silver grain density of tumor cell layer decreased rapidly within the first day after 20 Gy of irradiation, and continued to fall during day 2. Grain density of granulation tissue was 25% of tumor cells and was unchanged after irradiation. Macrophages and necrotic tissue showed low grain density and a small post-irradiation decrease. One day after irradiation, tumor cell showed giant cell formation and decreased cell density per unit area. The number of grains was greater in giant tumor cells than in non-irradiated tumor cell. Rapid response of Met uptake by tumor cells without a significant uptake by granulation tissue and macrophages suggest that 11C-Met is a suitable tracer for monitoring tumor radiotherapy with positron emission tomography.

Suppression of ischemia-reperfusion injury in murine models by neopterins

We investigated the effects of D-neopterin (NP) and its reduced form, 5,6,7,8-tetrahydro-D-neopterin (NPH4), in two models of ischemia-reperfusion injury, i.e., ischemic paw edema in mice and gastric ischemia in rats. In ischemic paw edema, iv administration of either NP or NPH4 more potently inhibited the increase of paw thickness after release from ischemia than did administration of superoxide dismutase plus catalase or allopurinol. In gastric ischemia, NP and NPH4 also significantly suppressed the formation of gastric mucosal erosions. Lipid peroxidation in the stomach was increased by ischemia-reperfusion treatment, and the increase was inhibited by the administration of NP or NPH4. The minimum dose of NPH4 required to suppress the gastric ischemic injury in this experiment was 0.3 mg/kg of body weight. These results suggest that neopterin may be effective as a protective agent against ischemia-reperfusion injury, in which active oxygen species are believed to play a major role.

[Pharmacokinetic, bacteriological, and clinical studies on SY5555 in children]

Pharmacokinetic, bacteriological and clinical studies on SY5555 were performed in children. The results were as follows: 1. A total of 15 patients considered to have bacterial infections were treated with SY5555. Each dose, 5 mg/kg, was orally administered 3 times daily, for 4-11 days. Clinical efficacies of SY5555 in 13 patients with bacterial infections (1 with pneumonia, 2 with bronchitis, each 1 with maxillary sinusitis, 2 with otitis media, 5 with pharyngitis, 1 each with gastroenteritis and pyelonephritis) were evaluated as excellent in 10 patients and as good in 3 patients with an efficacy rate of 100%. Two patients with viral infection and malignant lymphoma were not evaluated. Thirteen causative strains in 7 species were found in 10 patients. Streptococcus pneumoniae in 1/3, Haemophilus influenzae in 2/2, Streptococcus pyogenes 4/4, Salmonella spp. in 1/1, Escherichia coli in 1/1 were eradicated. Only one patient developed mild diarrhea as an adverse reaction. Another patient showed elevated GPT (glutamate pyruvate transaminase). The abnormality was mild and the patient recovered after the cessation of SY5555 administration without specific treatment. 2. MICs of SY5555 were examined against 33 clinical isolates. SY5555 has low MICs against Enterococcus faecalis and other Gram-positive cocci. 3. Pharmacokinetic studies Peak plasma concentrations of SY5555 was 1.15 micrograms/ml at a dose level of 4.9 mg/kg orally administered at fasting. Based on the above results and the broad spectrum of the anti-bacterial activities, SY5555 appears to be a promising antibiotics that is usable as a single agent for the primary therapy of respiratory tract infections, skin soft tissue infections and urinary tract infections in children.

Overview of effects of electrical stimulation on osteogenesis and alveolar bone

One endpoint of periodontal therapy is to regenerate structure lost to periodontal disease. Periodontal regeneration requires both formation of a new connective tissue attachment to the tooth and formation of alveolar bone. Several procedural advances may support regeneration of the attachment, however, regeneration of alveolar bone does not occur consistently. Therefore, factors which stimulate bone repair are areas for research in periodontal reconstructive therapy. Effects of cytokines or growth factors on bone repair are examples of such areas. Another one is electrical stimulation which naturally occurs in bone, and as such bone may be particularly susceptible to electrical therapy. This overview describes the potential of electrical stimulation for bone regeneration and applications in alveolar and periodontal research.

A time correlation study between reflectance spectroscopic cutaneous vasoconstriction and plasma corticosteroid concentration

Although cutaneous vasoconstriction assays are used as a primary screen for ranking the in vivo efficacy of new corticosteroids and in vivo human drug delivery studies, little is known about the relationship between the blanching reaction and corticosteroid tissue or plasma concentrations. We measured cutaneous vascular reactions in five volunteers, using an improved reflectance spectroscopic method, and a sensitive radioimmunoassay technique was employed to measure plasma betamethasone concentrations. Using a specially developed betamethasone-17-valerate patch prepared in BIO-PSA, constant corticosteroid release was ensured, and correlations between cutaneous blanching and plasma corticosteroid concentrations were calculated. Maximal skin blanching was documented 12 h post-application, whereas plasma corticosteroid concentrations peaked later, at 32 h post-application, when a paradoxical telangiectatic vasodilatation occurred. At 72 h post-application, when the plasma corticosteroid concentration was still above the 12 h level, this paradoxical vasodilatation was maximal. The corticosteroid-induced vascular reactions were mainly due to arterial haemoglobin (Oxy Haem), and both vasoconstriction and vasodilatation were related to changes in Oxy Haem. Our results suggest a dual, probably both time and concentration related, interaction between corticosteroids and dermal vessels in which lower concentrations at 6-12 h exposure caused vasoconstriction, but as the exposure time increased (> or = 24 h) paradoxical vasodilatation was induced, although plasma corticosteroid concentrations were still rising.

Early loss of pit and fissure sealant: a clinical and SEM study

The rate of early loss of preventive resin restoration and single application of pit and fissure sealant was determined by a clinical survey. The rate of partial and complete sealant loss on the observed surfaces was 14.4% (43/299) at the 3-month recall, with a further loss of 7.0% (12/171) between the 3- and 6-month recalls. Typically, a complete loss of sealant was observed on maxillary molars and on the buccal surface of mandibular molars, while partial loss caused on the occlusal surface of mandibular molars. Scanning electron microscopic observation of in vivo tooth replicas revealed partial gap formations and small fractures of sealant indicating failure or degradation of adhesion. The presence of unetched areas after routine cleaning and acid etching, especially in and around pits and fissures could be a major cause of early sealant loss.

[Minority versus majority: intergroup discrimination in the minimal group paradigm]

The present study was conducted to investigate the intergroup behaviour from the perspective of social identity theory. It was predicted that (a) when group membership was based on trivial categorization (e.g., by drawing lots), minority group members would be more conscious of their social identity, and favour their own group more in reward distribution than majority group members; (b) when based on value-loaded categorization (e.g., by social attitudes), both minority group and majority group members would favour their own group; (c) both minority group and majority group members would perceive converted members, who move away from their initial attitudes, as a threat to their social identity, and discriminate them. Results from three experiments under the minimal group paradigm, with undergraduate students, supported these predictions. Findings were discussed in terms of salience of social identity in categorization of minority versus majority, and the impact of anonymity in the minimal group paradigm. They were also discussed to compare the theory with belief congruence theory, which argues that attraction due to similarity of belief is the cause of ingroup favoritism.

Effects of preoperative chemotherapy on DNA ploidy patterns, cell cycle, and histological findings in gastric and colonic cancer patients

The effects of preoperative chemotherapy on gastric and colonic cancers have yet to be evaluated fully. In this study, its effects were assessed by studying DNA ploidy patterns, cell cycles, and histological findings in such patients. Thirty-nine patients with gastric or colonic cancer were given preoperative chemotherapy with UFT (an admixture of tegafur and uracil). Biopsy specimens for analysis were obtained before chemotherapy through a gastroscope or colonoscope and after chemotherapy from resected tumors. The DNA ploidy patterns and cell cycles were evaluated using a flow cytometer and the tissues were examined histologically. The DNA ploidy pattern was diploid (D) in 12 gastric and 13 colonic cancer patients and aneuploid (A) in 10 and 4 patients, respectively. After chemotherapy, the pattern changed in nine gastric (A-->D: 7, D-->A: 2) and six colonic cancer patients (A-->D: 3, D-->A: 3) and was unchanged in the remaining patients. Cell cyclic analysis showed decreased G1- and increased S-phase fractions in 10 of 12 patients with gastric and 6 of 10 patients with colonic cancer. Histologically, decreased tumor cellularity, increased fibrosis, and/or cytological changes were observed in both cancers after chemotherapy. Gastric and colonic cancers in which the DNA ploidy pattern changed from aneuploid to diploid, G1- decreased and S-phase increased, and/or histological changes were observed, were considered to have responded to preoperative UFT administration.

The inhibitory action of lead on mechanical responses of the proventricular smooth muscle in the chick

The purpose of the present experiments was to examine the mechanism of the proventricular dilatation caused by lead in the isolated vagus nerve-proventricular smooth muscle preparation of the chick. Lead caused dose- and time-dependent inhibition of contractions induced by vagal stimulation, transmural stimulation and externally applied acetylcholine (ACh). Vagally evoked contraction was much more sensitive to the inhibitory action of lead than the contractile response to ACh. The lower the frequency of transmural stimulation, or the lower the concentration of ACh was applied, the greater the inhibitory action of lead on the evoked smooth muscle contraction. The results suggest that proventricular impaction occurring in lead poisoning results from the pre- and post-synaptic inhibition of the vagus nerve-smooth muscle transmission.

A phase II study of vinorelbine, a new derivative of vinca alkaloid, for previously untreated advanced non-small cell lung cancer. Japan Vinorelbine Lung Cancer Study Group

To evaluate the effectiveness of vinorelbine (NVB) in patients with non-small cell lung cancer (NSCLC), a late Phase II study was conducted. A total of 80 patients with Stage III or IV NSCLC who had no previous therapy were entered into the study. Seventy-nine patients were eligible for response and toxicity. NVB was administered weekly by intravenous injection at a dose of 25 mg/m2 in 20 ml of saline and was generally administered in four cycles or more, unless patients had disease progression. Of the 79 eligible patients, 23 (29.1%) showed a partial response (95% confidence interval, 19.1-40.4%). The median duration of partial responses was 14.7+ weeks. The median survival time for all patients was 40.1+ weeks. The major toxicity was leukopenia. Grade 3 and 4 leukopenia occurred in 48 patients (60.8%). Other toxicities of grade 3 or more included anemia (6.3%), local cutaneous reaction (3.8%), pneumonitis (1.3%), nausea and vomiting (1.3%), mucositis (1.3%) and constipation (1.3%). The absolute dose-intensity of NVB was 22.33 mg/m2/week. A weekly schedule of intravenous administration of 25 mg/m2/week of NVB was reasonable for maintenance of activity, and acceptable for toxicity in the chemotherapy of advanced NSCLC.

Drug release from a suspension with a finite dissolution rate: theory and its application to a betamethasone 17-valerate patch

A random walk method for a diffusion equation is applied to the model for a suspension with a finite dissolution rate developed by Ayres and Lindstrom in 1977. In the method, the diffusion of dissolved drug and dissolution of crystal are calculated separately using a simple BASIC program. The random walk method strictly meets the principle of the conservation of mass as the drug amount in each sublayer rather than the concentration at each subinterval is concerned in the ointment. The model is used to analyze the release of betamethasone 17-valerate from a pressure-sensitive silicone adhesive into a sink. The drug release from the 1.50 mg/mL patch shows no substantial discrepancy from that predicted by the classic suspension model assuming an infinite dissolution rate. However, the classic model overestimates the release from the 3.08 and 5.88 mg/mL patches. The disagreement is lessened when the dissolution rate is assumed to be finite. However, the model does not give a perfect explanation because the drug release from the 3.08 and 5.88 mg/mL patches in the early phase is faster than the model predicts.

Immunoglobulin M and G antibodies in mice in response to Toxoplasma gondii (S-273) infection and their antigen recognition patterns in western blotting on various post-infection days

Immunoglobulin M and G antibody responses in mice experimentally infected with Toxoplasma gondii (S-273) and the reaction patterns with T. gondii (RH) tachyzoite antigens were studied on various post-infection days (PIDs) (2nd to 36th PIDs) using a commercially available IgM and IgG enzyme linked immunosorbent assay (ELISA) test systems and Western blotting (WB) technique. IgM antibody in ELISA test appeared to be positive on 12th PID (absorbance 0.764) and reached its peak level on 16th PID (absorbance 1.338) showing a slow decline thereafter with an absorbance of 0.800 even on 36th PID. Positivity of IgM was confirmed by WB except for 36th PID. IgG appeared on 16th PID with an absorbance of 0.248 and showed a steady increasing tendency even on 36th PID (absorbance 1.747). However, IgG positivity on WB was observed only on 29th PID and afterwards. On Western blots, both IgM and IgG showed interesting antigen recognition patterns on various PIDs. At the most IgM recognised seven antigens of 14kDa to 53kDa while IgG recognised eight antigens of 17kDa to 53kDa. Major antigens recognised by IgM were of 53kDa and 21kDa while the major band recognised by IgG was of 19kDa. The major bands, however, showed variability in their consistency during various PIDs. All the antigens recognised by IgM and IgG were not identical.

Antibodies against sulfated glycosphingolipids of peripheral nerve myelins detected in patients with human cytomegalovirus infection

In this paper we studied whether cytomegalovirus (CMV) infection could induce a production of antibodies against PNS glycosphingolipids (GL). Sera from patients with congenital CMV infection were tested for IgM and IgG antibodies against acidic and neutral GL purified from human PNS. TLC-immunostaining assay revealed that the CMV-infected patients' sera contained antibodies against sulfoglucuronyl glycosphingolipids (SGGL), which also bound to other sulfatide with a low affinity. No reactivity was observed to PNS gangliosides or neutral GL. The antibody also bound to other sulfated glycolipids including seminolipid and LacCer-sulfate, but not to cholesterol-sulfate, suggesting that a sulfated sugar chain may be important for their low-affinity binding. Furthermore, both anti-sulfatide and anti-SGGL antibodies were absorbed with sulfatide-conjugated octyl-Sepharose and heparin-Sepharose columns, whereas CMV-specific IgG titer was not decreased by the absorption of anti-sulfated GL antibody. These results suggest that CMV infection might specifically induce production of antibodies against sulfated GL, whereas these antibodies differed from CMV-specific antibody.

Working memory and prefrontal cortex

Several different types of memory have recently been proposed, some of which are believed to operate within specific areas in the brain. In this article, we will discuss the relationship between the prefrontal cortex and working memory, which is a recently proposed type of short-term memory. The tight relationship between the prefrontal cortex and working memory has been supported by recent human and animal studies. This relationship provides good evidence that a particular type of memory is related to a particular brain structure, and can be used as an important model for understanding the neuronal mechanisms of memory. In this article, we will present a modular model based on recent neurophysiological results and discuss for spatial working memory processes in the prefrontal cortex.

[Pharmacokinetic, bacteriological and clinical studies on cefozopran in children]

Pharmacokinetic, bacteriological and clinical studies on cefozopran (CZOP) were performed in children. The results were as followed: 1. A total of 13 patients were treated with CZOP. The tested dose was 20 mg/kg (50 mg/kg in maxillary sinusitis), and the drug administered via intravenous bolus injection or 30-minute intravenous drip infusion 3 times daily, for 3-11 days. Clinical efficacies of CZOP in 13 patients with bacterial infections (11 with pneumonia, 1 with otitis media and 1 with maxillary sinusitis) were evaluated as excellent in 13 with an efficacy rate of 100%. Any adverse reactions or abnormal laboratory test results were not observed in any patients. Fourteen causative strains were found in 10 patients. Streptococcus pneumoniae in 4 cases out of 4, Streptococcus pyogenes in 1/1, Moraxella (Branhamella) catarrhalis in 3/3, Haemophilus influenzae in 4/6 were eradicated. 2. Pharmacokinetic studies. The mean serum concentration immediately after intravenous drip infusion over 30-minute of 20 mg/kg was 39.1 micrograms/ml (range: 25.6-52.5 micrograms/ml). The mean urinary recovery rate over 8 hours after administration was 49.0% (range: 45.2-51.8%). Based on the above results and the broad spectrum and great antibacterial activity of CZOP, it is considered that CZOP is a promising antibiotic usable as a single agent for the primary therapy of acute bacterial infections ranging from mild to severe in children.

[A case of recurrent breast cancer responding to combination therapy with mitoxantrone (MIT), 5'-deoxy-5-fluorouridine (5'-DFUR) and medroxyprogesterone acetate (MPA)]

The patient was a 50-year-old woman who had undergone left standard radical mastectomy who had undergone left standard radical mastectomy on June 1, 1986. She showed multiple liver metastases with elevation of CEA level in July, 1991, and 5'-DFUR plus MPA combination therapy was started. The daily dosages were: 800 mg/body and 1,200 mg/body, respectively. After intra-arterial infusion of pirarubicin and Lipiodol, bilateral oophorectomy was performed and an implantable reservoir for intra-arterial infusion chemotherapy was implanted via the proper hepatic artery. Then she was treated by arterial-infusion of mitoxantrone 10mg/body intermittently every two weeks. The metastatic foci responded to this therapy and her CEA level decreased.

The role of duplication of tumour-derived chromosome 15 carrying the rearranged pvt-1 gene in the transformed phenotype of YACUT T-cell lymphoma × G4 T-cell line somatic cell hybrids in dictating the terminal differentiation program of the parental G4 cell

Fusion of the YACUT T-cell lymphoma with the Mls-1a-antigen-specific non-tumorigenic T-cell line G4 was previously reported to produce growth-arrested hybrids that could be induced to proliferate in the presence of Mls-1a antigen. The proliferation-suppressed hybrid lines exhibited phenotypic changes as follows: the usually high levels in YACUT of J11d antigen, IL-2 receptor, and c-myb expression, which are markers of immature T cells, were all down-regulated; the G4 T-cell function, i.e., contact helper activity for B-cell proliferation in T/B cell collaboration, was retained. Furthermore, fusion of the YACUT lymphoma with a killer T-cell line produced growth-arrested and tetraploid somatic cell hybrids having killer activity. Thus, in addition to the transformed phenotype (autonomous proliferation in vitro), the antigen-specific non-tumorigenic T-cell line genomes introduced into the YACUT lymphoma suppressed the immature phenotypes of YACUT and imposed their own programming of terminally differentiated traits on the hybrids. Prolonged growth of the proliferation-suppressed hybrid lines by repeated antigenic stimulation was previously reported to result in the appearance of transformed hybrids, which was accompanied by both a reversion of c-myc expression to the levels of YACUT and an increase in the number of chromosome 15. The present study revealed that the amplification of chromosome 15 resulted from the duplication of the tumour-derived chromosome 15 carrying the rearranged pvt-1 gene. However, the differentiated phenotypes of the hybrids remained mostly unchanged upon cell transformation.(ABSTRACT TRUNCATED AT 250 WORDS)

Significance of viable skin layers in percutaneous permeation and its implication in mathematical models: theoretical consideration based on parameters for betamethasone 17-valerate

The role of viable skin layers (viable epidermis and dermis) is examined by the three-layer model using parameter values for betamethasone 17-valerate. The mathematical three-layer diffusion model indicates that the lag time and half-life after vehicle removal in epidermis and split-thickness skin are longer than those in stratum corneum without viable layers, even if drug flux at steady-state is minimally altered. The theoretical values of the lag time and half-life predicted for epidermis and split-thickness-skin samples are compatible with the values observed in another in vitro study. The results predicted by the three-layer model indicate that the simplified model (single-layer or compartment model), which regards the whole skin as one diffusion layer or one compartment, may be warranted because all three skin layers have the same half-life after vehicle removal. The parameters used in the simplified model are estimated from some of the following values directly obtainable in the experiment: flux from skin and amount in the whole skin at steady-state, lag time, and drug concentration or amount maintained to be unchanged in the donor site. However, the simplified model often cannot resolve some discrepancy between the data and model (e.g., the ratio of the half-life to lag time) even if the data may be explained by the three-layer model.

[An evaluation of the hemodynamics in metastatic liver tumor by using ultrasound color Doppler flow mapping examination]

Eighty-one patients with metastatic liver tumors were studied by ultrasound color Doppler flow mapping examination. Primary origins consisted of gastric (19 cases), colorectal (40 cases), breast (7 cases), pancreatic (3 cases), gallbladder (3 cases) cancers and the others (9 cases). Metastatic lesions originated from breast, gastric and colorectal cancers had higher detection rates, however no blood flow could be observed within metastatic liver cancers from pancreatic and gallbladder cancers. There were no differences among the maximum blood flow velocity (Vmax), the resistance index (RI) and the pulsatile index (PI) in various metastatic liver tumors. In case of colorectal cancers, metastatic lesions originated from moderately differentiated adenocarcinoma had significantly lower RI (p < 0.05) and PI (p < 0.01) than that from well differentiated adenocarcinoma. In conclusion, ultrasound color Doppler flow mapping examination is a useful method for evaluation of the blood flow within metastatic liver tumors and could offer the histological differentiation of the primary origins, in case of metastatic liver cancers originated from colorectal cancers.

Seroepidemiological study of toxoplasmosis in two different geographical areas in Nepal

A total of 302 serum samples collected from Chitawan (159) and Mustang (143) districts of Nepal were included in this study. Anti-toxoplasma antibody was detected using micro-latex agglutination (MLA) and ELISA methods. An overall positive rate was found to be 57.9%. The positive rate in Chitawan was significantly higher (64.1%) (less than 1,000 m altitude) compared to that in Mustang (51.0%) (more than 3,000 m altitude) (p < 0.05). Females in Chitawan showed significantly higher positive rate (71.2%) compared to males (56.9%) (p < 0.05). On the contrary, though insignificantly, males showed higher positive rate (57.9%) compared to that of females (43.3%) in Mustang. Almost equal positive rate was observed among males in both study area. Females in Chitawan showed significantly higher (71.2%) positive rate compared to their counterparts in Mustang (43.3%) (p < 0.001). A slight increase in positive rate with age was observed in Chitawan while in Mustang a decreasing trend was noticed. Ethnically though statistically not significant, Indo-Aryans showed a higher positive rate (69.2%) compared to the positive rate shown by Tibeto-Burmans (63.1%) in Chitawan while the reverse was true in Mustang (Tibeto-Burmans: 53.8% and Indo-Aryans: 38.4%). Interestingly, 2.9% and 1.3% of MLA positive samples showed toxoplasma IgM antibody. None of the IgM positive samples were positive for toxoplasmic antigens.

Lag time in the dual sorption model for percutaneous absorption with finite skin-receptor boundary clearance

The lag time in the dual sorption model for percutaneous drug absorption with finite skin-receptor boundary clearance is examined. The effect of the change in the perfusional resistance on the lag time in the dual sorption model is found to be similar to, but a little less prominent than, that in the linear model. It is suggested that the lag time is roughly proportional to the amount in the skin at the steady state. Two numerical methods are used in predictor-corrector combination to obtain a numerical solution of the parabolic partial differential equation, together with the associated initial and boundary conditions, which arise in a nonlinear mathematical model of percutaneous drug absorption. Numerical estimates are obtained for the drug concentration profiles, the cumulative amount of drug excreted into the blood, the flux in the transient and steady states, the lag time, and the amount of drug in the skin per unit area in the steady state.