A new silicon detector telescope for measuring the linear energy transfer distribution over the range from 0.2 to 400 keV/micrometer in space

A new telescope consisting of three two-dimensional position-sensitive silicon detectors which can measure the linear energy transfer (LET) distribution over the range from 0.2 to 400keV/micrometers has been developed as a real-time radiation monitor in manned spacecraft. First, the principle of LET measurement and its design method are described. Second, suitable electronic parameters for the LET measurement are experimentally determined. Finally the telescope performance is investigated by using, relativistic heavy ions. The first in-flight test of this type of telescope on the US Space Shuttle (STS-84) is scheduled for May, 1997.

[An oral repeated dose toxicity study of a new antineoplastic agent S-1 in dogs. I. A 13-week repeated dose toxicity study. II. An ophthalmologic toxicity recovery study]

S-1, an antineoplastic formulation of a fluorinated pyrimidine derivative containing tegafur (FT), CDHP, and potassium oxonate (Oxo) in a molar ratio of 1:0.4:1, was recently developed by Taiho Pharmaceutical Co., Ltd., with the aim of prolonging the effective plasma concentration of 5-fluorouracil (5-FU) over that producted by FT alone and reducing its dose-limiting gastrointestinal toxicity. As a part of the S-1 toxicity study, a 13-week repeated dose toxicity study and a recovery study of opthalmologic effects were conducted in dogs. The following results were obtained. All S-1 doses are expressed in terms of their FT content. 1. Concerning the general condition, dark brown pigment was deposited on the sclera of the eye in all S-1 treated groups starting at the second week of treatment, and clouding of the cornea was noted in the 3 mg/kg/day group starting after 3-4 weeks of treatment. In the 3 and 6 mg/kg/day groups, general signs such as salivation, reduction in spontaneous movements, and sedation appeared, and 1 male and 2 females of the 3 mg/kg/day group died or were moribund 4-5 weeks after treatment began. All animals of the 6 mg/kg/day died or were sacrificed within 2 weeks of the start of the study. 2. Food consumption and body weight were reduced in the groups administered 1 mg/kg/day or more S-1. 3. No apparent drug-induced changes were observed on electrocardiography, urinalysis, fecal occult blood test, hematological examination, liver and kidney function tests, or ocular mucosa infection tests. 4. Blood biochemical examinations showed decreases in creatinine and chloride levels in males, an increase in LDH activity, and decreases in the albumin level and A/G ratio in females of the 3 mg/kg/day group. 5. Organ weighing showed that the relative weight of the kidney was increased in males and females of the 3 mg/kg/day group. 6. Histopathological examination revealed melanin deposition in the conjunctiva or cornea and atrophy inflammation, neutrophil infiltration, and neovascularization in the corneal epithelium. Atrophy of lymphatic tissues, such as the thymus, spleen and various lymph nodes, and changes in the reproductive system such as aspermatogenesis and uterine atrophy, which are commonly observed side effects of anticancer drugs, were also noted. 7. In the group administered FT, vacuolation of the cerebral fornix and commissura anterior was observed in 1 animal, but no changes were observed in other examinations. 8. The toxic effects of S-1 appeared primarily in the eyes, lymphatic tissues, and reproductive organs, and deaths were ascribed to weakening due to exacerbation of the general effects accompanied by disorders of immunological function. The NOAEL of S-1 in this study was estimated to be the dose that delivered less than 0.5 mg/kg/day in both males and females. 9. Changes in the eye observed after S-1 administration are such as pigmentation of the sclera and white turbidity of the cornea. Though it may be produced vision decreased, these changes are considered to be unaccompanied by functional disorders and to be reversible.

Separation of the subtypes of type V collagen molecules, [alpha 1(V)]2 alpha 2(V) and alpha 1(V) alpha 2(V) alpha 3(V), by chain composition-dependent affinity for heparin: single alpha 1(V) chain shows intermediate heparin affinity between those of the type V collagen subtypes composed of [alpha 1(V)]2 alpha 2(V) and of alpha 1(V) alpha 2(V) alpha 3(V)

The heparin affinities of heat-treated type V collagen alpha-chains and the triple-helical molecules were evaluated in terms of the NaCl concentration required for prevention of binding to a heparin-Sepharose column. After heat treatment, alpha 1(V) chain required approximately two-fold higher NaCl concentration to pass through the column than the other two chains, alpha 2(V) and alpha 3(V). Thus, the heparin affinity of alpha 1(V) may be approximately two-fold higher than those of the other alpha (V)-chains. The type V collagen molecules in triple-helical conformation were separated into two fractions at 170 mM NaCl in 20 mM phosphate buffer, pH 7.2, containing 2 M urea; bound and non-bound. The ratio of the three alpha-chains, alpha 1(V): alpha 2(V): alpha 3(V) was 2 : 1 : 0 and 1 : 1 : 1 in the bound and flow-through fractions, respectively, on analysis by SDS-PAGE. The differential affinity of the two fractions could be accounted for by the number of alpha 1(V) chains in the triple-helical molecule, if these fractions contained triple-helical subtypes with the chain compositions of [alpha 1(V)]2 alpha 2(V) and alpha 1(V) alpha 2(V) alpha 3(V), respectively. From the comparison of the NaCl concentration required for prevention of the binding, [alpha 1(V)]2, alpha 2(V) had about two-fold higher affinity than alpha 1(V) alpha 2(V) alpha 3(V), and the separated alpha 1(V) chain showed an intermediate affinity. A possible explanation for difference in heparin affinity among the subtypes of molecules and the separated alpha-chains is that the heparin affinity of type V collagen molecule is governed by the number of alpha 1(V) chains contained in the molecule and that steric restraint in a triple-helical conformation weakens the binding of alpha 1(V) chain to heparin.

[A 13-week oral repeated dose toxicity study of a new antineoplastic agent S-1 in rats]

S-1, an antineoplastic formulation of a fluorinated pyrimidine derivative containing tegafur (FT), CDHP, and potassium oxonate (Oxo) in a molar ratio of 1:0.4:1, was recently developed by Taiho Pharmaceutical Co., Ltd., with the aim of prolonging the effective plasma concentration of 5-fluorouracil (5-FU) over that produced by FT alone and reducing its dose-limiting gastrointestinal toxicity. As a part of the S-1 toxicity study, a 13-week oral repeated dose toxicity study and a recovery study using male and female rats was conducted. Doses of S-1 were adjusted to deliver 1.5, 5, and 15 mg/kg/day as doses of FT, and FT was given at 15 mg/kg/day. The following results were obtained. 1. In clinical observation, edema of the limbs and face or swelling of the auricle of the ear and an anemic appearance were observed in both sexes in the 15 mg/kg/day group as dose of FT. Subsequently, males in this group developed severe anemia, decreased spontaneous motor activity, emaciation, and subnormal skin temperature, and many males died. In the survivors, keratosis of the palm, sole, or tail was observed, with necrosis and loss of the tail tip in the severe cases. 2. Body weight gain was suppressed from about week 2 of treatment in both sexes in the 15 mg/kg/day group as dose of FT, and there was almost no weight gain after week 4-5. Food consumption was consistently less than the control value for males in the 15 mg/kg/day group as dose of FT throughout the treatment period. 3. No marked changes were observed in water intake and on opthalmologic examination. 4. In the fecal test for occult blood, a positive tendency was observed in both sexes in the 15 mg/kg/day group as dose of FT. 5. Urinalysis disclosed a slight increase in protein and decrease in sodium, potassium, and chloride in males, and an increase in protein in females in the 15 mg/kg/day group as dose of FT. 6. Hematologically, both sexes in the 15 mg/kg/day group as dose of FT showed decreases in red blood cell count, hemoglobin, and hematocrit, and increases in platelet count and fibrinogen, with a slight decrease in white blood cell count in males. 7. In the blood biochemical test, abnormal findings included increases in total cholesterol and free cholesterol, and decreases in non-esterified fatty acid and albumin in both sexes in the 15 mg/kg/day group as dose of FT. 8. In organ weight measurement, abnormal changes included a decrease in thymus weight in both sexes in the 5 mg/kg/day or higher dosage groups and a decrease in the testis weight in males and an increase in the liver weight in females in the 15 mg/kg/day group as dose of FT. 9. Histopathologically, both sexes in the 15 mg/kg/day group as dose of FT showed a decrease in the red pulp of the bone marrow, atrophy of the thymus, white pulp of the spleen, and testes. degeneration of the renal tubules, and ulcerative changes of the skin or oral mucosa. 10. The findings were unremarkable in the FT group. 11. During the recovery study, all the toxic effects tended to reverse. 12. The NOAEL of S-1 was estimated to be 1.5 mg/kg/day as dose of FT for both sexes.

[Development of deep vein thrombosis in an aplastic anemia patient with antiphospholipid antibodies]

A 38-year-old female was admitted to our hospital because of pancytopenia in April 1992. She was diagnosed as aplastic anemia by bone marrow biopsy and other examinations. Then she was treated with methyl-prednisolone pulse therapy followed by administration of cyclosporin in out-patient clinic. Though the modest improvement of peripheral blood count was observed, the worsening of pancytopenia was developed in association with tapering of cyclosporin. Anabolic steroid was given from June 1994 and gradual improvement of peripheral blood count was observed. On June 1995, she developed sudden onset of swelling and discoloration of a lower extremity, and thrombosis in the femoral vein was detected by Doppler ultrasonography. She was positive for lupus anticoagulant and anticardiolipin antibody, thus a diagnosis of antiphospholipid syndrome was made. Aplastic anemia associated with antiphospholipid syndrome has never been reported as far as we know. This case will be of importance for analyzing the cause of thrombosis in aplastic anemia.

[Oral single-dose toxicity study of a new antineoplastic agent S-1, and its components, CDHP, and Oxo]

S-1, an antineoplastic formulation of a fluorinated pyrimidine derivative containing tegafur (FT), CDHP, and potassium oxonate (Oxo) in a molar ratio of 1:0.4:1, was recently developed by Taiho Pharmaceutical Co., Ltd., with the aim of prolonging the effective plasma concentration of 5-fluorouracil (5-FU) over that produced by FT alone and reducing its dose-limiting gastrointestinal toxicity. As a part of the S-1 toxicity study, the single-dose toxicity of S-1 as well as that of its components, CDHP and Oxo, was investigated in mice, rats, and dogs. The following results were obtained. 1. In mice and rats, excretion of diarrheal stools, salivation, and alopecia were observed after S-1 administration. In severe cases, the animals subsequently showed emaciation due to weight loss or suppressed weight gain, decreased spontaneous motor activity, an anemic appearance, bradypnea, prone position, and death. In the CDHP and Oxo treatment groups of rats, the only toxic signs were soft or diarrheal stools on the dosing day. 2. In dogs, vomiting and excretion of diarrheal, mucous, or soft stools was observed after S-1 administration. In the CDHP and Oxo treatment groups, excretion of soft and diarrheal stools and vomiting were observed relatively frequently from the dosing day until day 1. 3. In the pathological examination of the animals given S-1, mice and rats showed pulmonary congestion/edema, dark red discoloration of the mesenteric lymph nodes, atrophy of lymphatic tissues such as the thymus and lymph nodes, decreases of lymphocytes in the splenic white pulp and mesenteric lymph nodes, a decrease in bone marrow cells, congestion of the glandular stomach, and aggregates of bacteria in the lung, liver, or spleen. In dogs, abnormal changes were observed mainly in the lymphatic organs such as the thymus and lymph nodes. 4. The LD50 values of S-1 in terms of the amount FT they contained were estimated to be 549 mg/kg for mice(male), 441-551 mg/kg for rats (both sexes) and about 53 mg/kg for dogs (male). The LD50 values of CDHP and Oxo were 2000 mg/kg or higher for both rats (both sexes) and dogs (male). 5. Hematopoietic and lymphatic impairments, immunosuppression associated with respiratory were considered to be the cause of death from S-1. The toxicity of S-1 reflects the toxicity of 5-FU and was not found the different toxicity by the addition of CDHP and Oxo.

Comparison of results of intracoronary implantation of the Plamaz-Schatz stent with conventional balloon angioplasty in chronic total coronary arterial occlusion

We compared angiographic and clinical outcomes after successful revascularization of chronic total coronary arterial occlusion with the placement of the Palmaz-Schatz stent (43 patients) and conventional balloon angioplasty (53 patients). After the procedure, the coronary stent led to a greater minimal lumen diameter than conventional balloon angioplasty (2.6 vs 1.7 mm, p < 0.001), resulting in a smaller residual stenosis (6.5% vs 36.7%, p < 0.001). At 6-month follow-up, there was no significant difference in late loss between the groups, resulting in a larger minimal lumen diameter at follow-up in the stent group (1.8 vs 1.1 mm, p < 0.001). The incidence of restenosis was lower in the stent group (27.9% vs 56.6%, p < 0.005). The frequency of the combination of myocardial infarction and coronary artery bypass graft surgery tended to be less in the stent group (2.3% vs 11.3%, P = 0.09). Placement of the Palmaz-Schatz stent improved left ventricular ejection fraction by 26% in patients who had reduced left ventricular function (p < 0.05), but conventional balloon angioplasty did not. Thus, placement of the Palmaz-Schatz stent provided a wider lumen than did conventional balloon angioplasty and, therefore, reduced the incidence of restenosis in chronic total coronary arterial occlusion. The lower restenosis rate of coronary stenting would be beneficial for long-term clinical outcome in patients with chronic total occlusion.

Expression of polymorphonuclear leukocyte adhesion molecules and its clinical significance in patients treated with percutaneous transluminal coronary angioplasty

OBJECTIVES

This study evaluated the role of neutrophil adhesion molecules LFA-1 (CD11a/CD18), Mac-1 (CD11b/CD18) and p150,95 (CD11c/CD18) in patients undergoing percutaneous transluminal coronary angioplasty (PTCA).

BACKGROUND

Several recent studies have suggested that cell adhesion molecules on both neutrophils and vascular endothelial cells play an important role in the process of tissue inflammation.

METHODS

Thirty-eight patients (30 men, 8 women; mean [+/-SE] age 56 +/- 5 years, range 38 to 76) with single-vessel coronary artery disease of the left anterior descending artery underwent coronary angioplasty. Peripheral blood was sampled at baseline before, immediately after and 12, 24, 48 and 144 h after PTCA. The expression of CD18, CD11a, CD11b and CD11c on the surface of polymorphonuclear leukocytes was examined by flow cytometry with monoclonal antibodies.

RESULTS

In patients without subsequent restenosis, there was no change in mean channel fluorescence intensity (MFI) of CD18 at each sampling time. However, in the patients with restenosis, the MFI of CD18 significantly increased at 48 h after PTCA (from 57 +/- 6 to 73 +/- 8, p = 0.0008). The MFI of CD11b increased slightly at 48 h after PTCA in patients without restenosis (from 584 +/- 121 to 735 +/- 114, p = 0.037). In patients with restenosis, the MFI of CD11b was slightly increased at 24 h after PTCA (from 586 +/- 122 to 768 +/- 214, p = 0.018) and significantly increased at 48 h after PTCA (to 1,534 +/- 268, p = 0.0006). The expression of CD11a and CD11c did not change at any sampling points after PTCA in either of the two patient groups. Percent change in the expression of CD18 at 48 h after PTCA (from baseline) and that of CD11b were correlated (r = 0.73, p = 0.0008) in patients with restenosis.

CONCLUSIONS

Inflammatory stimuli within the coronary vessels associated with coronary angioplasty may upregulate Mac-1 expression on the surface of polymorphonuclear leukocytes. This process may be more marked in patients who experience later restenosis. Thus, activation of neutrophil adhesion molecule Mac-1 at 48 h after PTCA may have value as a predictor of subsequent restenosis.

Measurement of LET distribution and dose equivalent on board the space shuttle STS-65

Space radiation dosimetry measurements have been made on board the Space Shuttle STS-65 in the Second International Microgravity Laboratory (IML-2). In these measurements, three kinds of detectors were used; one is a newly developed active detector telescope called "Real-time Radiation Monitoring Device (RRMD)" utilizing silicon semi-conductor detectors and others are conventional detectors of thermoluminescence dosimeters (TLDs) and CR-39 plastic track detectors. Using the RRMD detector, the first attempt of real-time monitoring of space radiation has been achieved successfully for a continuous period of 251.3 h, giving the temporal variations of LET distribution, particle count rates, and rates of absorbed dose and dose equivalent. The RRMD results indicate that a clear enhancement of the number of trapped particles is seen at the South Atlantic Anomaly (SAA) without clear enhancement of dose equivalent, while some daily periodic enhancements of dose equivalent due to high LET particles are seen at the lower geomagnetic cutoff regions for galactic cosmic ray particles (GCRs). Therefore, the main contribution to dose equivalent is seen to be due to GCRs in this low altitude mission (300 km). Also, the dose equivalent rates obtained by TLDs and CR-39 ranged from 146.9 to 165.2 microSv/day and the average quality factors from 1.45 to 1.57 depending on the locations and directions of detectors inside the Space-lab at this highly protected orbit for space radiation with a small inclination (28.5 degrees) and a low altitude (300 km). The LET distributions obtained by two different detectors, RRMD and CR-39, are in good agreement in the region of 15-200 keV/mm and difference of these distributions in the regions of LET < 15 keV/mm and LET > 200 keV/mm can be explained by considering characteristics of CR-39 etched track formation especially for the low LET tracks.

Strain differentiation and phylogenic relationships, in terms of base sequence of the ure B gene, of Helicobacter pylori

We constructed a phylogenetic tree based on the nucleotide sequence of the ure B gene of Helicobacter pylori strains, amplified by polymerase chain reaction (PCR). We analyzed the tree in terms of the relationship between the PCR-restriction fragment length polymorphism (RFLP)-genotype and the sequevar. The main frame of ure B (928 bp) was amplified by PCR from 38 strains of clinical isolates and reference species. The amplified probes were sequenced and processed into matrix and phylogenic trees. Homogeneity of the strains of "intra-case" origin and heterogeneity in "inter-cases" was parallel to clustering on the phylogenic tree. Sequevars in a cluster showed an identical RFLP-genotype in one case, indicating the clonal origin of H. pylori flora in an individual.

Postoperative adjuvant chemotherapy after radical hepatic resection for hepatocellular carcinoma (HCC)

BACKGROUND/AIMS

This prospective randomized study was aimed to clarify the efficacy of epirubicin after radical hepatic resection for hepatcellular carcinoma (HCC).

MATERIALS AND METHODS

One hundred and one patients entered the present study and were randomly allocated to Group A in which UFT (300 mg/day) was given from 5th postoperative week for one year, or Group B in which a bolus injection of epirubicin (40 mg/m2) was given arterially, in addition to the same UFT administration, on day 28. Groups A and B included 40 and 48 eligible cases, respectively.

RESULTS

No obvious intergroup differences were observed including prescribed dose of UFT. The 1-, 3- and 5-year survival rates (Groups A vs B) were 82 vs 90%, 50 vs 49% and 35 vs 30% (p = 0.2162). Excluding 4 operative deaths, the recurrence-free survival rates were 65 vs 70%, 32 vs 37% and 14 vs 17% (p = 0.3843). Initial recurrence sites were also similar.

CONCLUSIONS

A bolus arterial injection of epirubicin does not change the long term results after radical hepatic resection for HCC.

A histopathologic and immunohistochemical study of small nodules of renal angiomyolipoma: a comparison of small nodules with angiomyolipoma

Small mesenchymal nodules (SNs) are observed in some cases of renal angiomyolipoma (AML), with or without tuberous sclerosis. They are composed of blood vessels and/or nonvascular smooth muscle cells (SMCs) and/or fat cells. We examined 20 cases of AML, performed detailed histopathologic and immunohistochemical studies of SNs, verified the histologic relationship between SNs and AMLs, and compared the SNs of the tuberous/nontuberous sclerosis groups. Seventy-seven SNs were observed in five cases of AML. The SNs were 0.11 mm to 20.0 mm in diameter. The location of small-sized SNs in the kidney was variable; almost all of the SNs larger than 3.25 mm were in the renal capsule. The small-sized SNs contained mainly epithelioid-type nonvascular SMCs. Blood vessels and fat cells were not observed in the small-sized SNs but appeared gradually in the large-sized SNs. Almost all of the SNs were rounded lesions, and no fusion was observed between the SNs. Nonvascular SMCs of all of the SNs and AMLs were positive for vimentin, alpha-SM actin, and S-100 protein. The SNs less than 1.13 mm in diameter were negative for HMB-45; the nonvascular SMCs of AMLs and of SNs greater than 1.13 mm in diameter were positive for HMB-45. Nonvascular SMCs of SNs and AMLs showed a neurogenic phenotype. The SNs of the nontuberous sclerosis group contained only SMC components, whereas the same-size SNs of the tuberous sclerosis group contained SMCs, fat cells, and blood vessels. The SNs of the nontuberous sclerosis group may not increase in size or may grow slowly. Some of the SNs of patients with tuberous sclerosis grow to become AML. Although the SNs in patients with nontuberous sclerosis do not contain any blood vessels or fat cells, their SMCs show the histologic and immunohistochemical characteristics of AMLs; this indicates that SNs are the "buds" of AML.

[A 26-week oral repeated dose toxicity study of a new antineoplastic agent S-1 in rats]

S-1 was administered to male and female rats by gavage for 26 weeks at 0, 1, 5, and 10 mg/kg/day followed by 5-week recovery period for the control, 5, and 10 mg/kg/day groups. Treatment at 5 or 10 mg/kg/day in both sexes produced keratosis of the tail, palm or sole. Weight gain and average food consumption were lowered by the treatment. Urine showed increases in protein and epithelial or white blood cells and a decrease in specific gravity. The blood showed decreases in red blood cell count, hemoglobin, and hematocrit as well as increases in MCH, platelet count, fibrinogen, and MCV. A/G ratio, albumin, and chloride were decreased while total cholesterol, free cholesterol, triglycerides, and phospholipids were increased. Histopathologically, treatment-related changes at 5 and 10 mg/kg/day were observed mainly in the lymphoid tissues and kidneys. Those changes included atrophy in the lymphoid tissues and chronic nephropathy-like changes in the kidneys. Other changes in the 10 mg/ kg/day group, included acanthosis and/or inflammation in the epidermis of the tail, sole, or palm, degeneration and disarrangement of ameloblasts, and atrophy of the testes. In a recovery study, although some changes in the sole, palm, or tail, and the kidneys remained, they were less extensive than they had been at the end of the treatment period. Based upon these observations, the non-toxic dose level was estimated to be 1 mg/kg/day (2.3 mg/kg/day, as the summed doses of tegafur, CDHP, and Oxo) in both sexes.

MRI of intracranial meningeal malignant fibrous histiocytoma

We describe the CT and MRI findings in a patient with primary intracranial meningeal malignant fibrous histiocytoma (MFH). CT delineated the anatomical relations and MRI aided in tissue characterisation. To our knowledge, this is the first report describing the MRI findings in primary intracranial meningeal MFH.

Gelation of the lens capsule type IV collagen solution at a neutral pH

It is known that the type IV collagen extracted from EHS tumor assembles under a physiological condition, but not in a gel form. The EHS type IV collagen requires the other basement membrane components, laminin1, heparansulfate proteoglycan, and/or nidogen for gelation. On the other hand, Muraoka et al. reported that the bovine lens capsule type IV collagen alone gelated under a unique and unexpected condition of 2 M guanidine-HCl and 50 mM dithiothreitol, a condition which is thought to be dissociative for most biological macromolecules, including extracellular matrix [Muraoka, M. et al. (1996) J. Biochem. 119, 167-172]. The present report shows that the bovine lens capsule type IV collagen formed a gel under physiological conditions of pH and ionic environment, though the apparent rigidity of the gel was weaker than that of the gel formed in 2 M guanidine-HCl and dithiothreitol. The rigidity depended greatly on the incubation temperature and NaCl concentration of the type IV collagen solution, as observed in terms of the contractility of gel volume under centrifugal force. the gel formed in 150 mM NaCl and 20 mM phosphate, pH 7.3, at 28 degrees C contracted to 20% of the original volume on centrifugation of 1,800 x g for 10 min, while the gel formed at 4 degrees C, where type I collagen did not gelate at all, retained 90% of the original volume at the same centrifugal force. NaCl concentration was another important factor influencing the mechanical properties of type IV collagen gel. The gel formed at 150 mM showed maximal rigidity in the range of 0 to 300 mM in terms of the contractility on centrifugation. An image of a Pt/C replica of the gelated type IV collagen reconstituted at 4 or 28 degrees C in 20 mM phosphate, pH 7.3, containing 150 mM NaCl showed fine meshworks consisting of rather homogeneous pore sizes, resembling the skeletal structure of basal lamina. Since the condition where the type IV collagen alone formed gels was physiological in terms of ionic strength and pH, the aggregate structure and gel properties might reflect the in vivo type IV collagen supramolecular structure and the property.

A natural sulfated polysaccharide, calcium spirulan, isolated from Spirulina platensis: in vitro and ex vivo evaluation of anti-herpes simplex virus and anti-human immunodeficiency virus activities

A sulfated polysaccharide named calcium spirulan (Ca-SP) has been isolated from a sea alga, Spirulina platensis, as an antiviral component. The anti-human immunodeficiency virus type 1 (HIV-1) and anti-herpes simplex virus type 1 (HSV-1) activities of Ca-SP were compared with those of dextran sulfate (DS) as a representative sulfated polysaccharide. Anti-HIV-1 activities of these agents were measured by three different assays: viability of acutely infected CD4-positive cells, or a cytopathology assay; determination of HIV-1 p24 antigen released into culture supernatants; and inhibition of HIV-induced syncytium formation. Anti-HSV-1 activity was assessed by plaque yield reduction. In addition, their effects on the blood coagulation processes and stability in the blood were evaluated. These data indicate that Ca-SP is a potent antiviral agent against both HIV-1 and HSV-1. Furthermore, Ca-SP is quite promising as an anti-HIV agent because even at low concentrations of Ca-SP an enhancement of virus-induced syncytium formation was not observed, as was observed in DS-treated cultures, Ca-SP had very low anticoagulant activity, and showed a much longer half-life in the blood of mice when compared with that of DS. Thus, Ca-SP can be a candidate agent for an anti-HIV therapeutic drug that might overcome the disadvantages observed in many sulfated polysaccharides. When the role of chelation of calcium ion with sulfate groups was examined by removing calcium or its replacement by sodium, the presence of calcium ion in the molecule was shown to be essential for the dose-dependent inhibition of cytopathic effect and syncytium formation induced by HIV-1.

Upregulation of gap junctional intercellular communication in immortalized gonadotropin-releasing hormone neurons by stimulation of the cyclic AMP pathway

Increased gap junctional intercellular communication induced by agents that stimulate the adenylyl cyclase/cAMP pathway was observed in the GnRH-secreting neuronal cell line, GT1-7, and possible underlying mechanisms were examined. A 24-hour treatment of GT1-7 neurons with 100 microM dibutyryl cAMP + 100 microM IBMX or with 2 microM forskolin increased by greater than 2-fold the percentage of cells that were dye coupled, using the noninvasive dye coupling assay, fluorescent recovery after photobleaching (FRAP). Longer treatment times (48 h) and higher concentrations of dibutyryl cAMP (500 microM) did not further increase the percentage of dye-coupled cells, while there was no increase in dye coupling observed between untreated cells and cells treated for 2 h or less. The increase in dye coupling induced by dibutyryl cAMP/IBMX was inhibited by octanol or dieldrin, agents known to block gap junction-mediated intercellular coupling in other cell types. Western blot analysis of total protein or membrane protein-enriched extracts revealed no apparent difference in the cellular levels of connexin 26, a connexin subtype previously shown to be expressed by GT1-7 cells, between untreated cells and cells treated for 24 h with dibutyryl cAMP/IBMX or forskolin. In addition, expression of connexin 32 or 43 protein before or after treatment was not detected. On the other hand, a dramatic increase in both the number of neurites and neurites that immunostained positive for connexin 26 was observed in dibutyryl cAMP/IBMX-treated cells. We hypothesize that the observed increase in dye coupling between GT1-7 neurons following stimulation of the adenylyl cyclase/cAMP pathway results from an augmentation of cell-cell contacts due to an increased number of neurites containing gap junctional plaques, possibly through an effect on cellular differentiation.

[Drug induced hemolytic anemia associated with agranulocytosis]

A 27-year-old female was admitted to a hospital because of severe anemia (hemoglobin 4.9 g/dl) after taking PL (a drug for common cold consisted of Salicylamide, Acetaminophen, Caffeine and Promethazine methylene di-salicylate) and Cefadroxil (an oral antibiotic) for ten days. History and laboratory data leaded to a diagnosis of drug induced hemolytic anemia. 6 units of concentrated red blood cells were transfused and the suspected drugs were discontinued immediately. Though resolution of anemia and no further hemolysis were observed, progressive leukocytopenia developed since four days after the admission. Bone marrow aspiration revealed marked decrease of granulocytic series. The patient was transferred to our hospital and was isolated under laminar air-flow to prevent her from bacterial and fungal infections. She was treated with prednisolone and granulocyte-colony stimulating factor. She recovered from leukocytopenia in two weeks without suffering from any life-threatening infection. We extensively analyzed the suspected drugs and mechanism of hemolysis and granulocytopenia. Cefadroxil is turned out to be contributed to hemolysis by an immune complex mechanism. Cefadroxil and Salicylamide were suggested to be involved in granulocytopenia by the induction of antibodies against the leukocytes to which these drugs were bound. Thus Cefadroxil was regarded as a causative drug of both hemolysis and granulocytopenia. This case is of interest for analyzing drug-induced blood abnormality because it is very rare that two lineage of blood were injured by one drug at the same time as far as we know.

[Intravascular ultrasound in determining the end point of percutaneous transluminal coronary angioplasty]

Intravascular ultrasound (IVUS) imaging was used to measure internal luminal area immediately after percutaneous transluminal coronary angioplasty (PTCA) in 83 patients (59 males, 24 females, mean age 63 +/- 12 years) with angina pectoris to determine the need for additional intervention. The effectiveness of these interventions to prevent restenosis was also studied. Thirty-five patients (42%) with insufficient dilatation revealed an internal luminal area less than 5 mm2 or luminal stenosis greater than 60% as evaluated by IVUS imaging following the procedure. The luminal area increased from 4.5 +/- 1.1 to 7.9 +/- 2.8 mm2 and the percentage luminal stenosis improved from 66 +/- 9% to 54 +/- 9% in patients who underwent further dilatation with a larger size balloon, longer dilatation time, directional coronary atherectomy, or stenting. The insufficient dilatation group exhibited hard plaque and calcification more frequently than in the other group (48 patients, 58%) in whom sufficient dilatation of the target lesion was achieved. The incidence of restenosis in the sufficient dilatation group was 25%, compared to 33% of the patients receiving additional treatment after IVUS imaging and 42% in the 192 patients who underwent PTCA without IVUS imaging. IVUS imaging is a useful method for evaluation of complex luminal morphology to decrease the incidence of restenosis and for determination of the end point and the extent of dilatation required.

Immunohistochemical study of metalloproteinases and their tissue inhibitors in the lungs of patients with diffuse alveolar damage and idiopathic pulmonary fibrosis

Immunohistochemical and confocal microscopic studies of the localization of matrix metalloproteinases (MMPs), their tissue inhibitors (TIMPs), and type IV collagen were made in lung tissues from patients with normal pulmonary histology (n = 3), diffuse alveolar damage (n = 14), and idiopathic pulmonary fibrosis (n = 12). Pretreatment with pepsin revealed otherwise undetectable MMP- and TIMP-immunoreactive sites. In normal lung, MMP-2, MMP-9, TIMP-1, and TIMP-2 were localized in ciliated cells, endothelial cells, pneumocytes, macrophages, and smooth muscle cells; fibroblasts showed a strong reaction only for MMP-2. Only TIMP-2 showed co-localization with type IV collagen. Myofibroblasts and epithelial cells expressed increased reactivity for MMPs and TIMPs in both disorders. The reactivities for MMPs and TIMPs were stronger in diffuse alveolar damage. MMP-2 showed focal co-localization in capillary endothelial and disrupted epithelial basement membranes, suggesting activation of collagenolysis. A protective effect against this lysis was suggested by the extensive co-localization of TIMP-2 with type IV collagen and fibrillar collagens. Alveolar buds showed increased reactivity for MMPs and TIMPs in their lining epithelial cells, myofibroblasts, and their basement membranes; however, their matrices were mostly unreactive. These findings emphasize the complexity of the roles of MMPs and TIMPs in collagen turnover in diffuse alvcolar damage and idiopathic pulmonary fibrosis.

Prevalence of and risk factors for respiratory dyskinesia

We explored the prevalence of respiratory dyskinesia (RD), diagnosed objectively using a spirograph, and the major risk factors for tardive dyskinesia (TD) and RD. A total of 258 inpatients treated with neuroleptics was interviewed, and TD was evaluated using the Abnormal Involuntary Movement Scale (AIMS). Movement of the chest and respiratory regularity were assessed on clinical examination. Spirographs of patients with suspected RD were recorded, and RD was diagnosed based on spirographic data and the concurrence of two investigators. The prevalence of TD in this study was 22.1% (57 of 258). Aging and organic brain damage (OBD) were confirmed as risk factors; female gender, mood disorders, and the duration of neuroleptic exposure were not. Ten of 28 patients suspected of having RD were diagnosed with RD on the basis of persistent respiratory irregularities without other physiologic causes. The overall prevalence of RD was 3.9% (10 of 258) and was 17.5% (10 of 57) among the TD patient population. Four of these patients complained of dyspnea, and three demonstrated grunting. RD was more highly associated with aging and OBD than with TD itself. The identification of risk factors for RD is not only helpful in planning prophylactic strategies, but also facilitates the understanding of the pathogenesis of this syndrome.

Molecular-pathological analysis of a patient with three synchronous squamous cell carcinomas in the aerodigestive tract

A case of synchronous squamous cell carcinomas in the soft palate, larynx and esophagus is reported, along with findings of molecular-pathological analysis. A biopsy sample from the aryngeal carcinoma revealed well differentiated squamous cell carcinoma harboring two point mutations at codons 144 and 148 of the p53 gene but not at codon 299, and more than 50% of the cancer cells showed accumulation of p53 protein immunohistochemically. The esophageal tumor, which was moderately differentiated squamous cell carcinoma, showed immunoreactivity for p53 within the nuclei of 25-50% of cancer cells with a missense mutation at codon 299 but not at codon 144 or 148. This cancer also showed immunoreactivity for transforming growth factor alpha. On the other hand, the poorly differentiated squamous cell carcinoma in the soft palate showed negative immunoreactivity for p53 and no point mutation in exons 5 to 8 of the gene. These results suggest that the three synchronous squamous cell carcinomas arose as independent events.

[P300 findings in patients with corticobasal degeneration]

An auditory discrimination paradigm was employed to elicit the P300 component of the event-related potentials from three patients with clinically diagnosed corticobasal degeneration (CBD). Presenile and senile dementia of Alzheimer type (DAT), vascular dementia (VD) and age-matched control subjects were also examined. All patients with CBD manifested limb kinetic apraxia, hemiparkinsonism and mild dementia. Brain MRI revealed marked parietal atrophy, which was predominant in contralateral to the extremities with severe motor dysfunction. 123I-IMP SPECT analysis showed asymmetric reduction of cerebral blood flow, in accordance with the MRI findings. The P300 latencies in the two CBD patients were markedly prolonged compared to those of DAT and VD patients, although they were not as severely demented as DAT and VD patient. It should be noted that the P300 was not detected in one patient with CBD. The latencies of the N100 were not significantly different among the all groups. These abnormal findings of the P300 may be characteristic in CBD, and, furthermore, may be associated with the parietal lobe atrophy and low blood flow in cortex and thalamus revealed by brain MRI and SPECT.

Effect of overtime work on 24-hour ambulatory blood pressure

Recently, the adverse effects of long working hours on the cardiovascular systems of workers in Japan, including "Karoshi" (death from overwork), have been the focus of social concern. However, conventional methods of health checkups are often unable to detect the early signs of such adverse effects. To evaluate the influence of overtime work on the cardiovascular system, we compared 24-hour blood pressure measurements among several groups of male white-collar workers. As a result, for those with normal blood pressure and those with mild hypertension, the 24-hour average blood pressure of the overtime groups was higher than that of the control groups; for those who periodically did overtime work, the 24-hour average blood pressure and heart rate during the busy period increased. These results indicate that the burden on the cardiovascular system of white-collar workers increases with overtime work.