A numerical model for the analysis and evaluation of global 137Cs fallout

Fallout 137Cs from atmospheric nuclear detonation tests has been monitored worldwide since the late 1950's. The deviation and the correlation among these monitoring data were analyzed, and their surface deposition characteristics were estimated by the compartment model developed in this research. In the analysis, the scale of space (i.e., size of each compartment) and the degree of detail (i.e., number of compartments) were statistically determined using the global distribution data of 137Cs. The mathematical model was evaluated by comparing the numerically stimulated results with the fallout monitoring data including the 137Cs concentration in sea water. The major findings obtained in this research include that the deposition pattern of 137Cs is dependent on the latitude zone but not on the longitude, the mathematical model is promising for evaluating the dynamic performance of 137Cs in global atmospheric environment and its surface deposition, 137Cs is accumulated more in both the surface and deep ocean water of the North Pacific Ocean and the North Atlantic Ocean than that of other oceans, the 137Cs inventory is decreasing after the peak time in 1965, and the 137Cs inventory in the deep ocean water is decreasing more slowly than that in the surface ocean water.

[Usefulness of estriol for the treatment of bone loss in postmenopausal women]

To assess the effect of estriol (E3) on bone loss in Japanese postmenopausal women, twenty-five women within 10 years after menopause received 2 mg/day of E3 and 2 g/day of calcium lactate (Ca) daily (n = 17; Group-E3 + Ca) or 2 g/day of Ca daily (n = 8; Group-Ca) for one year. Bone mineral density (BMD) at the lumbar spine L2 - L4 was evaluated by dual energy X-ray absorptiometry (DXA). In Group-Ca, BMD was significantly reduced (p < 0.05 vs. pretreatment) at the end of the study period. In contrast, in Group-E3 + Ca, the mean percent increase in BMD was 1.66%, which was significantly higher than that of Group-Ca (-3.08%; p < 0.001). As for the biochemical markers of bone metabolism, bone specific alkaline phosphatase (ALPIII) reflecting bone formation, and pyridinoline (Pyr) and deoxypyridinoline (D-Pyr) reflecting bone resorption, were significantly decreased (p < 0.001) in Group-E3 + Ca after six months of treatment. These data indicate that the acceleration of bone turnover usually observed after menopause was prevented by treatment with E3. As to the side effects of E3, only one of the 17 patients experienced a slight increase in vaginal discharge, but no other side effects were observed. Accordingly, reasonable compliance can be expected among postmenopausal women treated with E3 to prevent bone loss.

[Two cases of long-term survival with hepatocellular carcinoma following targeting therapy with SMANCS/lipiodol]

We performed arterial infusion of SMANCS/Lipiodol in nineteen cases with hepatocellular carcinoma (HCC). We report two of these cases who survived for more than five years after the initial treatment. In case 1, HCC responded very well to the initial subsegmental infusion of SMANCS/Lipiodol with a prominent decrease in AFP level. In case 2, a 63-year-old male, repeated subsegmental infusion of SMANCS/Lipiodol for the local recurrence controlled the tumor well. In both cases, an approximately three-year period of complete remission passed until the tumor recurred. Arterial infusion of SMANCS/Lipiodol is expected to be a potent treatment for HCC. Its administration should be subsegmental, if possible, and should be repeated for local recurrence with a careful follow-up study.

Deletion in the 190 kDa antigen gene repeat region of Rickettsia rickettsii

The 190 kDa outer membrane protein of Rickettsia rickettsii is a major immunodominant protective antigen which contains 13 tandem nearly identical repeating sequences. We have identified a deletion in the 190 kDa antigen gene of R. rickettsii strain Smith maintained in the laboratory. The deletion occurred within the repeat region of this gene and the mutated repeat region corresponded to one repeating unit in size.

Thermoregulatory responses of prepubertal boys and young men in changing temperature linearly from 28 to 15 degrees C

To examine thermoregulatory responses of prepubertal children to cold stress, 11 boys (aged 8 years) and 11 young men (aged 19-23 years), wearing only trunks, participated in this study. They sat in air at 28 degrees C for 30 min (equilibrium period) and then in conditions where air temperature (Ta) was decreased linearly from 28 to 15 degrees C (at a constant rate of 0.22 degrees C.min-1) for 60 min, at a fixed relative humidity of 65%. In the equilibrium period there was no significant difference between the groups for rectal temperature [Tre, mean 37.30 (SEM 0.10) and mean 37.43 (SEM 0.14) degree C in the boys and the men, respectively] or for the respective skin temperatures (except for the forehead), but metabolic heat production (M) was significantly greater for the boys [mean 57.1 (SEM 1.2) and mean 52.0 (SEM 0.9) W.m-2, P < 0.005]. With declining Ta, the skin temperatures decreased in both groups (P < 0.001), but the decrease was significantly greater for the boys (P < 0.05), especially on the limbs as represented by the thigh and forearm. No significant correlations were observed between the limb skin temperatures compared to surface area-to-mass ratio or limb skinfold thicknesses in either group. The rate of increase in M as Ta decreased was significantly lower for the boys (P < 0.01) largely because of a higher M before the cold exposure. Thus, the mean M during the cold exposure did not differ between the groups [mean 63.6 (SEM 1.1) and mean 61.6 (SEM 1.1) W.m-2 in boys and men, respectively]. When the Ta was lowered, Tre in the boys started falling (P < 0.001), whereas the Tre in the young men did not change for 60 min. The Tre during the 60-min exposure was significantly lower (P < 0.001) for the boys [mean 37.01 (SEM 0.13) and mean 37.48 (SEM 0.18) degree C at the end of the exposure]. It was concluded that when Ta was lowered, the prepubertal boys appeared to vasoconstrict more in their limbs and to be somewhat more hypothermic, compared to the young men.

Oestradiol-induced relaxation of rabbit basilar artery by inhibition of voltage-dependent Ca channels through GTP-binding protein

1. Effects of oestradiol on the electrical and mechanical properties of the rabbit basilar artery were investigated by use of microelectrode, patch-clamp and isometric tension recording methods. 2. Oestradiol (10 nM-100 microM) relaxed arterial tissue pre-contracted by excess [K]o solution (30 mM) in a concentration-dependent manner. In Ca-free solution, histamine (10 microM) and caffeine (20 mM) each produced a phasic contraction, but oestradiol (10 microM) did not significantly affect their amplitude. 3. Oestradiol (< or = 100 microM) did not change the resting membrane potential of the artery whether in the presence or absence of TEA (10 mM). Action potentials observed in the presence of 10 mM TEA were abolished by oestradiol (100 microM). 4. Oestradiol (1 microM-100 microM) inhibited the voltage-dependent Ba current in a concentration-dependent manner. Oestradiol (100 microM) inhibited the Ba current observed in the presence of nicardipine (1 microM) more than that in the absence of nicardipine (to 31.0% vs 62.0% of control). 5. GTP gamma S (30 microM) in the pipette enhanced the inhibitory actions of oestradiol on the Ba current. On the other hand, with GDP beta S (1 mM) in the pipette, oestradiol failed to inhibit the Ba current. Pertussis toxin (PTX 3 micrograms ml-1) in the pipette totally prevented the inhibitory action of oestradiol on the Ba current. 6. Oestradiol (< or = 100 microM) had no significant effect on the outward K currents evoked by a membrane depolarization. 7. These results strongly suggest that oestradiol relaxes arterial tissue by inhibition of voltage-dependent Ca channels and that it inhibits both nicardipine-sensitive and -resistant Ca currents via a PTX-sensitive GTP-binding protein. The main target of oestradiol among the arterial Ca channels seems to be the nicardipine-resistant Ca channel, rather than the nicardipine-sensitive one.

Antihypertensive and metabolic effects of doxazosin in hypertensive patients with concomitant non-insulin-dependent diabetes mellitus

In this multicentre, non-randomized clinical study, 35 hypertensive patients with concomitant non-insulin-dependent diabetes mellitus were treated with the selective alpha 1 adrenoceptor blocker doxazosin mesilate for 24 weeks, either alone or together with existing antihypertensive therapy. The effects of the drug on blood pressure, glucose and lipid metabolism were examined. Daily administration of 0.5-8 mg doxazosin caused a significant reduction in both systolic and diastolic blood pressure decreased from 172 +/- 15/90 +/- 11 mmHg at the beginning, to 149 +/- 19/80 +/- 12 mmHg at the end of the trial. Heart rate was not affected. The plasma glucose level showed no change, whereas the haemoglobin A1c level decreased significantly from 7.4 +/- 1.2% to 7.1 +/- 1.2% (P < 0.01). Total and high-density lipoprotein cholesterol levels remained unchanged. The triglycerides level, however, decreased from 113 +/- 54 mg/dl at the beginning to 98 +/- 49 mg/dl at the end of the trial (P < 0.05). In a subgroup of patients, who showed hypercholesterolaemia ( > or = 220 mg/dl, n = 9) at the beginning, the total cholesterol level decreased from 252 +/- 33 mg/dl to 220 +/- 33 mg/dl (P < 0.05). Two patients complained of abdominal fullness or diarrhoea, but both were easily manageable. The results indicate that doxazosin is effective and safe in the treatment of hypertension in non-insulin-dependent diabetics and does not affect glucose metabolism. As for lipid metabolism in non-insulin-dependent diabetic patients, doxazosin seems to have a beneficial effect.

Visual inputs to cerebellar ventral paraflocculus during ocular following responses

The activity of cerebellar Purkinje cells was recorded in the ventral paraflocculus (VPFL) of alert monkeys during ocular following responses induced by brief movements of the visual scene. The mossy fiber input evoked 'simple-spikes' which increased their activity during either ipsiversive or downward motion of the visual scene. On the other hand, the 'complex-spikes' evoked by the climbing fiber input increased their activity during either contraversive or upward movement. To further define the sources of the visual input to the VPFL, we recorded single units in the dorsolateral pontine nucleus (DLPN), which is known to project to the VPFL as mossy fibers, and in the pretectal nucleus of the optic tract (NOT), which is known to project to the inferior olive whose neurons project to the cerebellum as climbing fibers. In both areas, most neurons were directionally selective, and responded to the moving visual scene with very short latencies (approximately 40-60 ms). These results suggest that both DLPN and NOT neurons deliver information concerning movements of the visual scene to the VPFL through different pathways.

Impaired synapse elimination during cerebellar development in PKC gamma mutant mice

PKC gamma is highly expressed in Purkinje cells (PCs) but not in other types of neurons in the cerebellum. The expression of PKC gamma changes markedly during cerebellar development, being very low at birth and reaching a peak around the third postnatal week. This temporal pattern of PKC gamma expression coincides with the developmental transition from multiple to single climbing fiber innervation onto each PC. In adult mutant mice deficient in PKC gamma, we found that 41% of PCs are still innervated by multiple climbing fibers, while other aspects of the cerebellum including the morphology and excitatory synaptic transmission of PCs appear normal. Thus, elimination of multiple climbing fiber innervation appears to be specifically impaired in the mutant cerebellum. We suggest that the developmental role of PKC gamma may be to act as a downstream element in the signal cascade necessary for the elimination of surplus climbing fiber synapses.

Directed inactivation of the psbI gene does not affect photosystem II in the cyanobacterium Synechocystis sp. PCC 6803

PsbI is a small, integral membrane protein component of photosystem II (PSII), a pigment-protein complex in cyanobacteria, algae and higher plants. To understand the function of this protein, we have isolated the psbI gene from the unicellular cyanobacterium Synechocystis sp. PCC 6803 and determined its nucleotide sequence. Using an antibiotic-resistance cartridge to disrupt and replace the psbI gene, we have created mutants of Synechocystis 6803 that lack the PsbI protein. Analysis of these mutants revealed that absence of the PsbI protein results in a 25-30% loss of PSII activity. However, other PSII polypeptides are present in near wild-type amounts, indicating that no significant destabilization of the PSII complex has occurred. These results contrast with recently reported data indicating that PsbI-deficient mutants of the eukaryotic alga Chlamydomonas reinhardtii are highly light-sensitive and have a significantly lower (80-90%) titer of the PSII complex. In Synechocystis 6803, PsbI-deficient cells appear to be slightly more photosensitive than wild-type cells, suggesting that this protein, while not essential for PSII biogenesis or function, plays a role in the optimization of PSII activity.

Oxidative stress response in yeast: glutathione peroxidase of Hansenula mrakii is bound to the membrane of both mitochondria and cytoplasm

The yeast Hansenula mrakii IFO 0895 induces glutathione peroxidase (GPx) when the cells are exposed to the oxidative stress such as lipid hydroperoxide, superoxide- and hydroxy radical-generating conditions. To clarify the localization of GPx in H. mrakii cell, distribution of the enzyme was investigated. After centrifugation of the yeast protoplast homogenates at 2500 x g for 10 min, 67% of total GPx activity was recovered from the supernatant (Sup. 1) and 33% was from the pellet (Pellet 1). When the Sup. 1 was fractionated by sucrose density gradient ultracentrifugation, GPx activity was essentially recovered from the mitochondria fraction. Submitochondrial localization of the enzyme showed that 95% and 2.5% of the enzyme was recovered from the inner and outer membrane, respectively. No GPx activity was detected neither in intermembrane space nor in matrix of mitochondria. On the other hand, at least 12% of total GPx activity was recovered from the purified plasma membrane which was obtained from the Pellet 1 by successive sucrose density gradient centrifugation. Thus, the GPx of H. mrakii is present in the inner and outer membrane of mitochondria as well as the plasma membrane.

[Home parenteral nutrition for terminal cancer patients--when should we tell the truth about their disease and return them to their home with HPN]

Home parenteral nutrition (HPN) is a significant way to enable terminally ill cancer patients to live with high quality of life at home. However, the most important condition to perform HPN is the patients' desire to return to their home. For this purpose, we should consider in informing them of the truth of their disease. We had three terminal cancer patients who returned to their home with HPN. Cas 1: 52-year-old woman, recurrent stomach cancer. She did not know her cancer. She stayed at home for 45 days with HPN. Case 2: 46-year-old woman, recurrent stomach cancer. She did not know her recurrence of cancer. She stayed at home for only 15 days with HPN. Case 3: 45-year-old woman, recurrent pancreatic head cancer. She knew her disease and her life expectancy. She had 6-year-old daughter and desired to return home. She stayed at home with HPN for 8 months. As we told Case 3 truth of her disease when she was diagnosed as recurrence of cancer, she lived at home with HPN for 8 months. From the experience of three cases, we may concluded that, the sooner the patients are informed the truth about their disease, the longer they can stay at home with HPN and spend their limited time with high QOL.

Ocular resurfacing and alloepithelial rejection in a murine keratoepithelioplasty model

PURPOSE

To determine definitively the epithelial origin of corneal resurfacing and to elucidate the immunologic mechanisms of epithelial rejection in a murine keratoepithelioplasty (KEP) model.

METHODS

After corneal epithelial removal and peritomy, donor corneal lenticules were grafted around the limbus (KEP procedure). The process of corneal reepithelialization was observed with 0.25% methylene blue staining. The origin of the renewed epithelium was determined by immunofluorescence. Syngeneic corneal lenticules were grafted to BALB/c mice. C3H/He, C57BL/6, BALB.K, DBA/2, and B10.D2 allogeneic corneal lenticules were grafted to BALB/c mice, and A.SW and A.TL allogeneic corneal lenticules were grafted to A.TH mice. Alloepithelial rejection was evaluated on the basis of clinical findings and histologic changes in grafted corneas.

RESULTS

All KEP grafts were reepithelialized entirely at 3 days after surgery. The renewed epithelium proved to be derived from the lenticules in BALB/c eyes receiving C3H/He lenticules. In syngeneic grafts 5 days after KEP, the cornea recovered clarity and smoothness, which persisted to the end of the study. After complete reepithelialization, all allogeneic grafts also experienced a short duration of clear cornea. Then followed four characteristic phases of inflammatory epithelial response: initial phase, acute phase, chronic phase, and rejected phase. Histologic examination confirmed the progress and severity of inflammatory response. The mean onset times of initial phase in assorted grafts with mismatched histocompatibility antigens were: 7.9 +/- 1.8 days for both major and minor disparity grafts, 9.5 +/- 3.8 days for major disparity grafts, 18.2 +/- 5.5 days for major histocompatibility class I disparity grafts, 25.6 +/- 7.2 days for major histocompatibility class II disparity grafts, and 9.2 +/- 2.2 days for multiple minor disparity grafts.

CONCLUSIONS

In donor corneal lenticule grafting to host eyes with corneal epithelium removed and conjunctival peritomy, the ocular surface was reepithelialized by lenticule-derived epithelium. Alloepithelial rejection in this model displayed characteristic manifestations and well-defined processes, enabling easy and precise evaluation of onset and intensity of graft rejection. Both major and minor histocompatibility antigens are related to corneal epithelial rejection.

[Experience with the Groshong port in a home TPN patient--a case report]

We experienced a home TPN patient using Groshong port. A 45-year-old woman, recurrent pancreatic head cancer, was treated with home TPN. The Groshong port was inserted via external jugular vein and stayed at home for 8 months with home TPN. Lipid emulsion was administered twice a week. After administration of lipid emulsion, 20 ml of saline was injected and catheter lock was performed with only saline. Heparin was not used for catheter lock. After 8 months' home TPN, patient died. We could not find any precipitate in the catheter and reservoir. A unique feature of Groshong port is a pressure-sensitive two-way valve at the intravascular end. The valve of this port opens outward during fluid infusion or bolus injection. During blood withdrawal, the valve opens inward and then closed after the procedure. Because the valve is designed to remain closed between -7 and 80 mmHg, it will not open spontaneously under normal central venous pressure conditions. This valve eliminates the need for heparin flusing. Catheter obstruction during prolonged TPN is a serious complication. Compound of heparin, lipid emulsion and electrolytes, especially calcium is now becoming one of the most important causes of catheter obstruction and catheter removal. We used the Groshong port to prevent catheter obstruction. After 8 months' use of this port, no precipitate was found in this port. We conclude that the Groshong port is useful for home TPN catheter because it can prevent catheter obstruction due to heparin-lipid-electrolytes compound.

Immortalization of human T cells expressing T-cell receptor gamma delta by herpesvirus saimiri

Herpesvirus saimiri (HVS) has recently been shown to immortalize human CD4+ and CD8+ T cells expressing T-cell receptor alpha beta (TCR-alpha beta) with the maintenance of their original phenotypes and functional properties. However, the immortalization of human T cells expressing TCR-gamma delta by HVS has not been successful. Here we report that HVS can also infect and immortalize human T cells expressing TCR-gamma delta. Two human TCR-gamma delta+ T-cell clones, which continuously proliferated in interleukin-2-containing culture medium without any exogenous stimulation or addition of feeder cells for more than 8 months, were established by HVS infection. Morphologically, the HVS-transformed TCR-gamma delta+ T-cell clones were granular lymphocytes which exhibited wide-range HLA-unrestricted cytotoxicity as untransformed TCR-gamma delta+ T cells. Their phenotypes and cytotoxic activities were not altered during long-term culture. The immortalization of human TCR-gamma delta+ T cells by HVS infection would be useful for functional analysis of this lymphocyte population, which is believed to play an important role in protection against various infectious diseases.

The chronological change of vertebral bone loss following oophorectomy using dual energy X-ray absorptiometry: the correlation with specific markers of bone metabolism

The changes of vertebral bone mineral density (BMD; g/cm2) following oophorectomy were studied, using dual energy X-ray absorptiometry (DEXA) in 38 premenopausal and 244 oophorectomized women. Two biochemical indices of bone remodeling, urinary deoxypyridinoline (DPyr) for bone resorption and serum intact human osteocalcin (hOC) for bone formation, were also measured at the same time. The rate of bone loss in the first year after oophorectomy was 10.7%, while that in the second year was 5.7% (rapid phase), followed by a slow phase at the rate of 1.1%. The bone mass finally reached an osteoporotic level (BMD < 0.767 g/cm2) at 12 years after oophorectomy. The DPyr increased to reach a peak level in the first year, whereas the hOC increased and reached its peak level in the second year after surgery. The maximal bone loss in the first year is considered to be caused by the remarkable increase of bone resorption and the biological delay of the maximal increase in bone formation.

Nucleotide sequence of the psaD gene from the thermophilic cyanobacterium Synechococcus vulcanus

The nucleotide sequence was determined for the psaD gene of a thermophilic cyanobacterium, Synechococcus vulcanus, which encoded the PsaD subunit (Subunit II) of the Photosystem I reaction center complex. Except for some differences in the peripherals, the nucleotide sequence of the gene encoding PsaD was identical to that of another thermophilic cyanobacterium Synechococcus elongatus reported previously. Relationship between these primary structures and thermostability was also discussed.

Impaired tumor phenotypes in class II major histocompatibility complex antigen-inducible cells originated from human lung adenocarcinoma

The class II major histocompatibility complex (MHC) antigens play important roles in T cell activation and are thought to be involved in tumor development. Using anti-class II antibodies with interferon gamma (IFN-gamma), we have here selected class II MHC antigen positive cancer cells from the human lung adenocarcinoma cell line A549, which is originally negative (> 95%) for the antigens. A part of the class II antigen-positive cells presented a flat morphology, which was not observed in the parental A549 cells. Class II antigen expression in these flat cells was IFN-gamma inducible; there was a correlation between the inducibility and phenotypic changes. A class II antigen-inducible flat subline restored the ability of contact inhibition and anchorage-dependent growth as well as lost tumorigenicity in athymic mice.

An independent role of cytochrome c-550 in cyanobacterial photosystem II as revealed by double-deletion mutagenesis of the psbO and psbV genes in Synechocystis sp. PCC 6803

Cytochrome (cyt) c-550 and the 33 kDa protein are two extrinsic components that function in maintaining oxygen evolution in cyanobacterial cells. Deletion of either of the two components has been shown to result in cyanobacterial phenotypes that are still capable of photoautotrophic growth albeit with a reduced rate. In order to study the function of cyt c-550 in cyanobacterial photosystem II (PSII) and its possible interaction with the 33 kDa extrinsic protein, we constructed a mutant lacking both cyt c-550 and the 33 kDa protein by inactivating the psbV and psbO genes simultaneously in a cyanobacterium, Synechocystis sp. PCC 6803. The resultant double-deletion mutant was unable to grow photoautotrophically and showed almost no oxygen-evolving activity (less than 10% of the wild type). This residual activity was also lost rapidly upon illumination, suggesting an increased sensitivity of the mutant cells toward photoinhibition. Thermoluminescence measurements indicated that the mutant virtually cannot undergo normal charge accumulation (S-state transitions) leading to oxygen evolution. Herbicide-binding and Western blot analyses showed that the mutant accumulates the PSII complex to an extent of only 20% of that in wild-type cells. Combined with previous results, the present results indicated that cyt c-550 supported oxygen evolution in the single-deletion mutant lacking the 33 kDa protein alone and vice versa. Thus, both cyt c-550 and the 33 kDa protein function independently in maintaining cyanobacterial oxygen-evolving activity in vivo, and both of them are required for the optimal activity.(ABSTRACT TRUNCATED AT 250 WORDS)

cDNA cloning and characterization of gibberellin-responsive genes in photoblastic lettuce seeds

Two cDNA clones, cLRG5 and cLRG11, that respond to gibberellin (GA) were isolated from seeds of photoblastic lettuce (Lectuca sativa L. cv. Grand Rapids) by differential screening. Northern blot analysis indicated that the levels of LRG5 and LRG11 mRNAs were raised to slightly higher levels 10 h after the start of GA treatment and the levels were maintained at least for further 8 h, while those in the control seeds gradually decreased. Red light irradiation had effects similar to GA treatment. The cLRG5 insert encodes a putative polypeptide of 380 amino acids that is highly homologous to alcohol dehydrogenases from several higher plants. With regard to the cLRG11 insert, no homologous gene has been reported.