Attenuation of cold stress-induced exacerbation of cardiac and adipose tissue pathology and metabolic disorders in a rat model of metabolic syndrome by the glucocorticoid receptor antagonist RU486

OBJECTIVES

Chronic stress affects the central nervous system as well as endocrine, metabolic and immune systems. However, the effects of cold stress on cardiovascular and metabolic disorders in metabolic syndrome (MetS) have remained unclear. We recently characterized DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, derived from a cross between Dahl salt-sensitive and Zucker rats, as a new animal model of MetS. We have now investigated the effects of chronic cold stress and glucocorticoid receptor (GR) blockade on cardiac and adipose tissue pathology as well as on metabolic parameters in this model.

METHODS

DS/obese rats were exposed to cold stress (immersion in ice-cold water to a depth of 1-2 cm for 2 h per day) with or without subcutaneous injection of the GR antagonist RU486 (2 mg kg(-1)day(-1)) for 4 weeks beginning at 9 weeks of age. Age-matched homozygous lean (DahlS.Z-Lepr(+)/Lepr(+)) littermates served as a control.

RESULTS

Chronic cold stress exacerbated hypertension as well as left ventricular (LV) hypertrophy, fibrosis and diastolic dysfunction in DS/obese rats in a manner sensitive to RU486 treatment. Cold stress with or without RU486 did not affect body weight or fat mass. In contrast, cold stress further increased cardiac oxidative stress as well as macrophage infiltration and proinflammatory gene expression in LV and visceral fat tissue, with all of these effects being attenuated by RU486. Cold stress also further increased GR and 11β-hydroxysteroid dehydrogenase type 1 mRNA and protein abundance in LV and visceral adipose tissue, and these effects were again inhibited by RU486. In addition, RU486 ameliorated the stress-induced aggravation of dyslipidemia, glucose intolerance and insulin resistance in DS/obese rats.

CONCLUSIONS

Our results implicate GR signaling in cold stress-induced exacerbation of cardiac and adipose tissue pathology as well as of abnormal glucose and lipid metabolism in a rat model of MetS.

Preparation of Spherical Titania Particles from Inorganic Precursor by Homogeneous Precipitation

Spherical titania particles can be prepared in a short time period from an aqueous solution of TiOSO4 by homogeneous precipitation using urea at 70–90°C. Although the hydrolysis of TiOSO4 continues to a considerable extent even in the absence of urea, the presence of urea is essential for the formation of spherical particles. The average particle size produced was l–4μm and changed mainly with the concentration of TiOSO4. As-synthesized powders are amorphous hydrates of titania containing sulfate group and crystallize by calcination into anatase(>500°C) and rutile(>900°C). In calcination, the particles shrink, but hold their original spherical shapes.

Increased intensity of acute graft-versus-host disease after reduced-intensity bone marrow transplantation compared to conventional transplantation from an HLA-matched sibling in children

Eight children underwent reduced-intensity stem cell transplantation (RIST) from an HLA-matched sibling. They received a fludarabine-melphalan based preparative regimen. Stem cell source was bone marrow, and GVHD prophylaxis consisted of cyclosporine A alone. Acute GVHD grade II-IV and grade III-IV were observed in four (50%) and three (37.5%), respectively, out of these eight patients. This incidence was significantly higher than that after conventional bone marrow transplantation, without severe tissue damage, in the same setting of stem cell source and GVHD prophylaxis. Although the number of patients is small, our results suggest that incidence of acute GVHD after RIST for children is significant. It should be remembered that RIST for children does not seem to be an easy transplant procedure from the viewpoint of acute GVHD, although RIST is less toxic.

The useful combination of a higher frequency miniprobe and endoscopic submucosal dissection for the treatment of T1 esophageal cancer

BACKGROUND

There are few published data on the discrimination ability of endoscopic ultrasonography (EUS) among each subdivision of T1 cancer, and overdiagnosis is an unsolved problem that eventually causes overtreatment. The purpose of this study was to verify whether our treatment strategy incorporating EUS realizes a tailored patient management of T1 esophageal cancer.

METHODS

This study comprised 20 esophageal cancer patients undergoing 12- to 20-MHz miniprobes for T staging and a 7.5-MHz dedicated echoendoscope for N staging. Initial therapy constituted endoscopic submucosal dissection (ESD) for endosonographically node-negative, mucosal, or slight submucosal cancers and a primary esophagectomy with three-field lymphadenectomy for deeper cancers. If the ESD specimen revealed no cancer involvement of the muscularis mucosa, the patients entered a follow-up program; otherwise, they were advised to undergo a subsequent esophagectomy and three-field lymphadenectomy.

RESULTS

Perfect discrimination accuracy was achieved among T1, T2, and T3 cancers. Whether cancer depth was up to the slight submucosal layer or deeper was correctly differentiated in 12 of 14 T1 cancers (86%). EUS categorized all patients correctly into candidates for either ESD or surgery. The pathological cancer depth of the resected specimens revealed that no patients experienced unnecessary overtreatment.

CONCLUSIONS

A higher frequency miniprobe is useful for the detailed evaluation of cancer depth, contributing to decision making for treatment options of T1 esophageal cancer. A miniprobe and echoendoscope in combination with ESD provide an appropriately tailored management plan on an individual basis, avoiding unnecessary treatment or indicating radical surgery.

Cytotoxic Chemotherapy Successfully Induces Durable Complete Remission in 2 Patients with Mosquito Allergy Resulting from Epstein-Barr Virus-Associated T-/Natural Killer Cell Lymphoproliferative Disease

Recent findings indicate that Epstein-Barr virus (EBV)-infected T-/natural killer (NK) cells play an important role in the pathogenesis of mosquito allergy, and most patients with mosquito allergy die early in life if not properly treated. Over the last 7 years, we have been using combination chemotherapy and allogeneic stem cell transplantation for the treatment of EBV-associated T-/NK cell lymphoproliferative disease (LPD) in which chronic active EBV infection and mosquito allergy were included. As of this writing, we have successfully treated 2 patients with mosquito allergy with chemotherapy in which EBV-infected T-/NK cells were eradicated. The findings suggest the possible role of chemotherapy in the treatment of EBV-associated T-/NK cell LPD.

A seasonal variation in the onset of postoperative adhesive small bowel obstruction is related to changes in the climate

BACKGROUND

Postoperative small bowel obstruction following abdominal procedures is more common in patients who have undergone laparotomy. However, little is known about the influence of climate on the incidence of postoperative small bowel obstruction.

METHODS

To evaluate whether seasonal climatic variations are a risk factor for postoperative small bowel obstruction, hospital-based, retrospective case series was designed from medical records of 230 patients suffering from postoperative small bowel obstruction admitted to the Tokyo University Branch Hospital. Detailed analysis of weather charts from the Japanese Meteorological Agency and review of medical records for selected patients who were diagnosed with postoperative small bowel obstruction. The obstruction was diagnosed by abdominal X-ray imaging, clinical examination, and patient interviews.

RESULTS

A total of 233 patients diagnosed with postoperative small bowel obstruction were identified. Analysis of the medical records of these 233 patients revealed that the variables associated with an increased risk of postoperative small bowel obstruction included low ambient temperatures of 5-10 degrees C, an increase in air humidity by 40-50% and air pressure of 1010-1015 hPa.

CONCLUSION

The typical winter weather in Tokyo is characterised by low temperatures, low humidity and moderate air pressure. These winter climate conditions could be correlated with an increased incidence of postoperative small bowel obstruction in Tokyo during our period.

Inhibition of human telomerase by nucleotide analogues bearing a hydrophobic group

Telomerase, which synthesizes telomeric DNA in eukaryotic cells, is classified as a reverse transcriptase. To clarify the susceptibility of telomerase to nucleoside 5'-triphosphates bearing a hydrophobic group on the base moiety, we studied the inhibitory effects of 2',3'-dideoxy-5-styryluridine 5'-triphosphate analogues and 9-(beta-D-arabinofuranosyl)-2-(p-n-butylanilino)purine 5'-triphosphate analogues on telomerase activity using a quantitative 'stretch PCR' assay. 2',3'-Dideoxy-5-styryluridine 5'-triphosphate (StddUTP) showed more potent inhibition than 2',3'-dideoxythymidine 5'-triphosphate (ddTTP). On the other hand, 9-(beta-D-arabinofuranosyl)-2-(p-n-butylphenyl)guanine 5'-triphosphate (BuParaGTP) showed no inhibition, even though 9-(beta-D-arabinofuranosyl)guanine 5'-triphosphate (araGTP) is a potent inhibitor of telomerase. The influence on telomerase of hydrophobic substituents on the base moieties of nucleotides is described.

Development of a membrane dialysis bioreactor and its application to a large-scale culture of a symbiotic bacterium, Symbiobacterium thermophilum

A simple membrane dialysis bioreactor was developed for a large-scale axenic culture of Symbiobacterium thermophilum, a symbiotic thermophile that requires co-cultivation with an associating thermophilic Bacillus strain S for normal growth. The bioreactor consisted of an outer- and an inner-coaxial cylindrical compartment bordered across a dialyzing membrane, which enabled a 1 l-scale dialysis culture with exchange of low molecular metabolites between the two compartments to be performed. Using the bioreactor, growth characteristics of S. thermophilum and Bacillus strain S were assessed under two medium conditions. The growth of S. thermophilum was measured by quantitative PCR because the bacterium formed no visible colonies and gave abnormally low turbidity. In medium containing 2% tryptone peptone, S. thermophilum proliferated up to 4x10(7) cells/ml, and strict dependence on the co-culture with Bacillus strain S was observed. On the other hand, medium containing 0.5% yeast extract not only facilitated the growth of S. thermophilum in the co-culture (6x10(7) cells/ml), but also allowed limited pure growth independent of Bacillus strain S (1x10(7) cells/ml), implying that some component of yeast extract can partially replace the growth requirement of S. thermophilum supplied by Bacillus strain S. Both the oxidative redox potential values and the cell morphology in the independently growing culture suggested the occurrence of marked unbalanced growth possibly caused by significant metabolic changes. The bioreactor is applicable to the analyses of culturing characteristics in symbiotic systems between free-living microorganisms.

The effect of propafenone on premature ventricular contractions (PVC): an analysis based on heart rate dependency of PVCs

The effect of 450 mg/day propafenone for two weeks on premature ventricular contractions (PVCs) was studied in combination with an assessment of heart rate (HR) dependency of PVCs using Holter ECG monitoring in patients with more than 720 PVCs per day. The PVC-HR correlation was classified into positive (P), bidirectional (B), and flat and negative (FN) correlation groups. The positive group included only patients in whom PVC frequency increased with a heart rate increase, while the bidirectional group included patients with PVCs whose frequency increased at low heart rates and decreased at high heart rates. The FN group contained both flat (PVC frequency was almost fixed regardless of heart rate changes) and negative (PVC frequency decreased as heart rate increased) correlations. The effectiveness of propafenone was 70% in the positive group and 50% in the nonpositive group which included both bidirectional (67%) and FN (0%) groups, using a > 70% PVC reduction as a criterion of efficacy. From this, we concluded that propafenone is effective in patients showing either positive or bidirectional PVC-HR correlation. The coupling interval (CI) of PVCs was also prolonged by propafenone as a whole. The present study suggests that there are differences in the mechanism of PVC development in patients with flat or negative correlation and those with a positive or bidirectional correlation. Thus, this type of analysis contributes to an understanding of the action of antiarrhythmic agents, and may allow the prediction of their efficacy on PVCs.

Successful delivery in a pregnant woman with lupus anticoagulant positive systemic lupus erythematosus treated with double filtration plasmapheresis

The case was a 29 year old female who has suffered from systemic lupus erythematosus (SLE) since 15 years of age. The activity of SLE was low, and she took prednisolone orally. Her first pregnancy failed after 14 weeks. In the second pregnancy, she had thrombocytopenia, prolonged activated partial thromboplastin time (APTT), positive lupus anticoagulant (LAC) and thus was diagnosed with antiphospholipid antibody syndrome (APS). Combination therapy with steroids and aspirin was started, and she underwent treatment of double filtration plasmapheresis (DFPP) in the early stage of pregnancy. Her platelet count increased, and the value of APTT has normalized with DFPP treatment. She delivered successfully on the 32nd week of pregnancy. We think that DFPP is an effective and safe treatment in patients with an LAC positive pregnancy.

Diabetes mellitus associated with rapidly progressive glomerulonephritis with perinuclear antineutrophil cytoplasm antibodies

A 55-year-old woman who had been treated for diabetes mellitus for twenty-five years developed interstitial pneumonia and rapidly progressive glomerulonephritis (RPGN). The findings of light microscopy revealed fibrocellular crescent formation in all glomeruli and infiltration of lymphoid cells in interstitium. There were no deposits in the intracapillary area and mesangial area on both immunofluorescence and electron microscopy. Her interstitial pneumonia improved with pulse therapy of methylprednisolone and her hematuria disappeared with mix treatment of cyclophosphamide and double filtration plasmapheresis (DFPP). Her serum creatinine level improved from 2.2 mg/dl to 1.5 mg/dl. Interstitial pneumonia and hematuria did not recur at twelve months after the first hospitalization. This report presents a rare case with RPGN associated with diabetes mellitus who recovered with combination therapy of cyclophosphamide, steroid and DFPP.

Intraoperative lavage for cytological examination in 1,297 patients with gastric carcinoma

BACKGROUND

This study examined the clinical value of intraoperative peritoneal lavage for cytological examination in patients with gastric cancer. Peritoneal dissemination is the most frequent mode of recurrence for this tumor.

METHODS

A retrospective of lavage findings, other factors, and outcome was performed in 1,297 patients with gastric cancer who underwent intraoperative peritoneal lavage.

RESULTS

The 5-year survival rate of patients with positive lavage cytology was only 2%. Patients who underwent curative resection and had negative cytology had a significantly better 5-year survival rate (P < 0.001). Even among patients with macroscopic peritoneal dissemination, the survival rate was significantly better with negative cytology, which reflected fewer free cancer cells in the peritoneal cavity. Serum concentrations of carcinoembryonic antigen and carbohydrate antigen 19-9 were significantly higher in patients with positive cytology. Multivariate analyses indicated that intraoperative cytological findings was an independent prognostic factor for survival, and was the most important factor for predicting peritoneal recurrence.

CONCLUSIONS

Intraoperative peritoneal lavage cytology is important in predicting survival and peritoneal recurrence in gastric cancer.

Molecular analysis and diagnosis in Japanese patients with Wilson's disease

BACKGROUND

Wilson's disease is characterized by the toxic accumulation of copper in the liver, brain, cornea and other organs. It is caused by both impaired excretion via the bile and impaired incorporation of copper into ceruloplasmin in the liver. The Wilson's disease gene (ATP7B) has been cloned as a putative copper-transporting P-type ATPase gene. We therefore analysed mutations of ATP7B in Japanese patients with Wilson's disease.

METHODS

Twenty-three Japanese patients with Wilson's disease were investigated. In all patients, the ATP7B coding sequence, including exon-intron junctions, was analysed by restriction endonuclease digestion, mutation detected enhancement gel electrophoresis and/or direct sequencing analysis of amplified fragments.

RESULTS

Thirteen mutations were identified, including seven missense mutations, four detections, one insertion and one exon skipping in the coding region. The most common mutations were 2874deletion(del)C in exon 13 and arginine (Arg)778 leucine (Leu) in exon 8.

DISCUSSION

None of the observed mutations, except for 2302insertion(ins)C, have been previously detected in either European or North American patients. We conclude that the mutation spectrum of Wilson's disease may thus indicate a population-dependent pattern. Based on the population-dependent manner of the occurrence of ATP7B gene mutations, it may be possible to establish a molecular diagnosis system. A molecular diagnosis system is considered to be very effective for making a definitive diagnosis in very young patients and for also detecting carriers.

[The clinicopathological analysis of lymph node metastasis of gastric cancer]

One hundred-twenty-one cases of curative resection for gastric cancer with lymph node metastasis were analyzed to determine the prognostic value of the nodal stage (n), number of metastatic lymph nodes, maximum diameter of metastatic lymph nodes, micrometastasis of lymph nodes, histological type of lymph node metastasis, extranodular invasion and infiltration into lymphatic vessels around metastatic lymph nodes. In patients with a higher nodal stage the survival rate was lower and the nodal stage was a good prognostic indicator. Inpatients who had 7 or more metastatic lymph nodes or in whom the maximum diameter of the metastatic lymph nodes was over 15 mm or who had not only micrometastasis of lymph nodes, the survival rate was lower. These results suggest that quantitative analysis of metastatic lymph nodes is necessary. In patients who had nudifferentiated type metastatic lesions of lymph nodes, the survival rate was lower than in those with the differentiated type and the difference was larger than for the primary lesion. In patients who had extranodular invasion or infiltration into lymphatic vessels around metastatic lymph nodes, the survival rate was decreased. These results suggest that histopathological analysis of metastatic lymph nodes is necessary.

Histamine modulates high-voltage-activated calcium channels in neurons dissociated from the rat tuberomammillary nucleus

The effects of histamine on high-voltage-activated Ca2+ channels in the histaminergic neurons acutely dissociated from the rat tuberomammillary nucleus were investigated in the nystatin-perforated patch recording mode under voltage-clamp conditions. Histamine suppressed the high-voltage-activated Ca2+ channel currents in neurons which were positive for histidine decarboxylase with immunocytochemistry. The half-maximum inhibitory concentration and maximum inhibition were 2.6 x 10(-7) M and 16.6+/-1.90%, respectively. An H3 receptor agonist, R(-)-alpha-methylhistamine, mimicked the response to histamine, and thioperamide, an H3 receptor antagonist, inhibited the response to histamine. On the other hand, neither 2-methylhistamine, an H1 receptor agonist, nor dimaprit, an H2 receptor agonist, had a significant effect on the Ca2+ channel currents. Pretreatment with pertussis toxin blocked the inhibitory effect of histamine on Ca2+ channels, suggesting the involvement of Gi/Go proteins in the action of histamine. Omega-conotoxin-GVIA, omega-agatoxin-IVA, nicardipine, and omega-conotoxin-MVIIC blocked the high-voltage-activated Ca2+ channel currents by 15.6, 4.3, 27.1, and 31.2% of the total current, respectively, suggesting the existence of N-, P-, L-, and Q-type Ca2+ channels. A current that was insensitive to these blockers was also found. This residual current, "R-type", was completely suppressed by the addition of 200 microM Cd2+. Histamine significantly inhibited both the N- and P-type current components among these five types of Ca2+ channel currents. We concluded that histamine suppresses the N- and P-type Ca2+ channels in histaminergic neurons through an H3 receptor which is linked to a pertussis toxin-sensitive G-protein.

Arginine enhances induction of T helper 1 and T helper 2 cytokine synthesis by Peyer's patch alpha beta T cells and antigen-specific mucosal immune response

The effects of arginine on cell proliferation and subsequent T helper (Th) 1 and Th 2 cytokine synthesis by murine Peyer's patch (PP) Th cells in vitro and the influence of arginine on the induction of antigen-specific mucosal and systemic immune responses in vivo were examined. When the PP T cells were stimulated with the anti-alpha beta T cell receptor (TCR) antibody in the presence of different concentrations of arginine, a higher proliferative response was observed in the culture with an optimal concentration of arginine compared with that with a minimum amount of this amino acid. The concentration of cytokines in the supernatant, the number of cytokine-producing cells and the cytokine-specific mRNA expression of PP T cells were also increased in a dose-dependent fashion. Furthermore, when mice fed on an arginine-supplemented liquid diet were orally immunized with tetanus toxoid plus cholera toxin as a mucosal adjuvant, a higher level of antigen-specific fecal IgA was observed when compared with the response in mice fed on an arginine-free diet. Taken together, these results suggest that arginine enhanced antigen-specific mucosal immune response resulting from the supporting activation of cell proliferation and subsequent cytokine synthesis of PP Th cells.

Protective effect of administration of skim milk on exogenous and endogenous infection in mice

In order to minimize the denaturation of proteins in milk, normal cow's milk was pasteurized at 61 C for 20 min. The protective effects of the thus prepared skim milk (low-heat skim milk) on exogenous and endogenous infection were examined as compared with conventional skim milk which was pasteurized at 121 C for 2 sec. The antibody titers to Listeria monocytogenes and Escherichia coli of low-heat skim milk were almost equal to that of raw milk, while no antibody was detected in the conventional skim milk. When mice were given low-heat skim milk or conventional skim milk, the incidence of the translocation of orally inoculated Listeria monocytogenes to the spleen was lower in the low-heat skim milk group than that in the conventional skim milk group. The life span of 7 Gy X-ray irradiated mice given low-heat skim milk was significantly prolonged in comparison to that of mice given conventional skim milk. However, there were no differences in the number of bacteria in the feces or IgA production by Peyer's patch cells between the two groups. These results suggest that antibodies in low-heat skim milk, which still have reactivity to exogenous or indigenous bacteria, may contribute to the protective effects against bacterial infection.

Long-lasting salivation induced by a novel muscarinic receptor agonist SNI-2011 in rats and dogs

The sialogogic effect of SNI-2011, a novel muscarinic receptor agonist, (+/-)-cis-2-methylspilo [1,3-oxathiolane-5,3'-quinuclidine] hydrochloride, hemihydrate, was compared with that of pilocarpine hydrochloride in a dose range in which the two muscarinic agonists exhibited approximately similar efficacy in eliciting salivation. Pilocarpine (0.66-2.0 mg/kg, i.d.) induced a marked but short-lasting salivation in rats, whereas the salivation induced by SNI-2011 (20-60 mg/kg, i.d.) lasted 1.4- to 1.8-fold longer. In dogs, the sialogogic effect of SNI-2011(1-3 mg/kg, i.v.) also lasted about 2-fold longer than that of pilocarpine (0.1-0.3 mg/kg, i.v.). The plasma SNI-2011 level that caused salivation at a rate of 0.4 ml/min was about 100 ng/ml and higher rates of salivation (over 0.4 ml/min) induced by 1 mg/kg SNI-2011 lasted for about 90 min in dogs. The plasma pilocarpine level that caused salivation at a rate of 0.4 ml/min was about 25 ng/ml and the higher rate of salivation (over 0.4 ml/min) induced by 0.1 mg/kg pilocarpine lasted only for 20 min in dogs. Effective plasma levels of SNI-2011 persisted longer than those of pilocarpine. These results indicate that SNI-2011 may be useful in the treatment of xerostomia because of its long-lasting sialogogic action.

Synthesis and cataleptic effects of optically active dihydrohaloperidols and dihydrobromoperidols

Optically active dihydrohaloperidols and dihydrobromoperidols, the major metabolites of haloperidol and bromoperidol, clinically used as neuroleptic drugs in humans, were asymmetrically synthesized by Jaen's method. The motor effects of all the reduced haloperidol and bromoperidol metabolites were evaluated by the mouse catalepsy test. The results indicate that administration of the optically active dihydrohaloperidols and dihydrobromoperidols as well as haloperidol and bromoperidol can cause significant motor deficits in mice.

Suppression of K+ conductance by metabotropic glutamate receptor in acutely dissociated large cholinergic neurons of rat caudate putamen

1. Responses to metabotropic glutamate receptor (mGluR) activation were investigated in acutely dissociated rat neostriatal (caudate putamen, CP) large cholinergic neurons, with the use of a nystatin-perforated patch-clamp technique. 2. Application of L-glutamate (Glu) in the presence of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) induced a slow inward current accompanied by a decrease in membrane conductance at a holding potential (VH) of -44 mV. 3. The ratio of the maximal amplitude of the slow inward metabotropic glutamate (mGlu) response to that of the ionotropic glutamate response for large cholinergic CP neurons was larger than that for the hoppocampal CA1, CA3, and dentate gyrus neurons the nucleus tractus solitarii neuron, cerebellar Purkinje neuron, and granule cell of the main olfactory bulb. The threshold and half-maximal effective concentration values of these mGlu responses were 10- to 30-fold lower than those of the respective ionotropic responses. 4. Specific agonists of the mGluR, quisqualate (QA), (+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (tACPD), (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid [(1S,3R)-ACPD], and (2S,3S,4S)-alpha-carboxycyclopropyl-glycine [L-CCG-1), similarly induced slow inward currents at the same VH. The relative affinities of the mGlu agonists were QA > Glu > L-CCG-1 > (1S,3R)-ACPD. L-CCG-1 did not induce any current at concentrations < 10(-6) M. 5. DL-2-amino-3-phosphonopropionic acid or DL-2-amino-4-phosphonobutyric acid did not block the mGlu response, whereas (RS)-alpha-methyl-4-carboxyphenyl-glycine, a selective mGluR antagonist, partially reduced the mGlu response. 6. The reversal potential of the mGlu response was close to the K+ equilibrium potential, and it shifted by 56.4 mV for a 10-fold change in extracellular K+ concentration. In 90.6% of the neurons tested, the instantaneous current induced by hyperpolarizing voltage steps was markedly suppressed during the mGlu response. In 9.4% of the neurons, the currents elicited by step pulses showed a voltage-dependent slow relaxation that was not affected by mGluR activation. 7. Under the current-clamp mode, the slow afterhyperpolarization (AHP) following a spontaneous discharge was not affected by tACPD. The AHP current was not blocked under the voltage-clamp mode, either. 8. (1S,3R)-ACPD or Glu in the presence of CNQX elicited membrane depolarization accompanied by increased rate of action potentials under the current-clamp mode. Tetrodotoxin had no effect on the membrane depolarization. 9. These results indicate that the mGluR on large cholinergic CP neurons is mainly of the mGluR1 and/or mGluR5 type, and it plays a significant role in controlling the membrane potential by way of suppressing the leak K+ conductance.

Modulation of rhythmical slow activity, long-term potentiation and memory by muscarinic receptor agonists

We investigated the cholinergic modulation of hippocampal rhythmical slow activity (or theta activity), long-term potentiation and a behavioral memory task. The intravenous administration of the muscarinic receptor agonists, AF102B ((+/-)-cis-2-methyl-spiro(1,3-oxathiolane-5,3') quinuclidine hydrochloride hemihidrate) and oxotremorine, induced rhythmical slow activity at doses of 1.0 mg/kg and 0.01 mg/kg, respectively. Long-term potentiation of population spike amplitude in the hippocampal CA1, which was induced by tetanic stimulation to the Schaffer collateral/commissural fiber, was increased by AF102B (1.0 mg/kg i.v.) and oxotremorine (0.01 mg/kg i.v.). Oral administration of AF102B and oxotremorine improved scopolamine-induced memory deficits in a passive avoidance task in mice at doses of 1.0 mg/kg and 0.2 mg/kg, respectively. The correspondence of the effective doses of muscarinic receptor agonists in these three experiments suggested the cholinergic correlation of rhythmical slow activity, long-term potentiation and memory.

Two components of metabotropic glutamate responses in acutely dissociated CA3 pyramidal neurons of the rat

The excitatory and inhibitory actions of metabotropic glutamate receptor (mGluR) agonists were investigated in acutely dissociated rat hippocampal CA3 pyramidal neurons, using the conventional whole-cell and nystatin-perforated patch recording configurations under the voltage-clamp condition. With the conventional whole-cell recording, glutamate (Glu) and quisqualic acid (QA) induced only ionotropic inward currents accompanied by increased membrane conductance at a holding potential (VH) of -45 mV. The response was reversibly blocked in the presence of D-2-amino-5-phosphonopentanoic acid (D-AP5) and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), the antagonists of N-methyl-D-aspartate (NMDA) receptor and non-NMDA receptor, respectively. With nystatin-perforated patch recording, mGlu responses insensitive to both D-AP5 and CNQX were observed. Fifty-five % of the cells responded by a slow inward current accompanied by conductance decrease (ImGlui) at a VH of -44 mV. One % of the neurons showed an outward current with conductance increase (ImGluo), and 34% of the neurons showed ImGluo followed by ImGlui. The onset of ImGluo occurred approximately 900 ms after the response to 30 mM K+. The time to peak of ImGluo were 32- to 79-times longer than those of ionotropic responses. ImGlui appeared at lower concentrations than ionotropic Glu responses, whereas ImGluo appeared at similar concentrations as ionotropic responses. The rank order of affinity was QA > Glu > (+/-)-1-aminocyclopentane-trans-1, 3-dicarboxylic acid (tACPD) for both ImGlui and ImGluo. Half-maximal effective concentrations (EC50) and the threshold concentrations for the three agonists were four- to tenfold lower for ImGlui than for ImGluo. The current-voltage relationship showed that the reversal potentials of ImGlui and ImGluo shifted 55 and 59 mV, respectively, for a tenfold change in extracellular K+ concentration, indicating that K+ is the charge carrier of both mGlu responses. During ImGlui, both the leakage current and muscarine-sensitive voltage-dependent K+ current (M current) were suppressed. ImGluo induced by 10(-4) M tACPD was abolished by 3.10(-7) M charybdotoxin and 10(-6) M ryanodine. These results show that there are two components of mGlu responses in CA3 pyramidal neurons and that ImGlui and ImGluo show different pharmacological properties.

Effect of carnitine on decrease of branched chain amino acids and glutamine in serum of septic rats

Blood concentrations of branched chain amino acids (BCAA; leucine, isoleucine, and valine) and glutamine (Gln) decrease markedly in sepsis. We investigated the effect of carnitine on serum concentrations of BCAA and Gln in fasted septic rats. Rats were made septic by cecal ligation and puncture. They developed extremely high blood concentrations of endotoxin, and serum concentrations of BCAA and Gln were markedly decreased 2 d after the operation. When L-carnitine was administered subcutaneously to the rats at 500 mg/kg body weight every 12 h for 2 d starting at the operation, no decrease in the serum concentrations of BCAA and Gln was observed. This indicates that the administration of carnitine can prevent the decrease of serum concentrations of BCAA and Gln in septic animals.

Beneficial effects of enteral fat administration on liver dysfunction, liver lipid accumulation, and protein metabolism in septic rats

The purpose of this study was to examine the effect of different amounts of fat in enteral diets on liver function, liver lipid accumulation, and protein metabolism in septic rats. Sepsis was induced in Wistar rats by cecal ligation and puncture. The rats were divided into four groups and were fed enterally 0% (FO, n = 7), 10% (F10, n = 7), 20% (F20, n = 8), or 30% (F30, n = 9) of total calories as fat. The liquid diet consisted of medium-chain and long-chain triglyceride mixtures as the fat sources, casein oligopeptide, and dextrin (100 kcal/100 ml). Intraduodenum feeding was ended on the 6th day. Serum glutamic oxaloacetic transaminase and glutamic pyruvic transaminase activities, indices of liver dysfunction, were highest in the FO group, and triglycerides accumulated in the livers of that group, possibly because of the large proportion of carbohydrate in the diet. Value of nitrogen balance was highest in the F 10 group, and serum total protein and albumin concentration were higher in the F10 and F20 groups than in the FO and F30 groups. The liver protein content in the F10 and F20 groups was higher than in the FO and F30 groups. Serum triglyceride in the F30 group was about 2 times higher than in the F10 and F20 groups. These results indicate that enteral fat administration in septic rats as 30% of total calories reduced liver dysfunction and liver triglyceride accumulation, but might have been excessive for optimal protein metabolism. Therefore, the preferable amount may range from 10% to 20% of total calories.

[A new protein titrator tape for self-assessment by outpatients with proteinuria]

ł- have invented a new dipstick (protein titrator tape) for measuring the volume of protein excreted in the 24-hour urine. The principle of the method is based on the protein error of indicators with the modification of a conventional dipstick test. The dipstick consists of two thick filter papers, containing differently adjusted pH indicators of tetrabromphenol blue, making it possible to detect a wide range of protein concentrations in the urine using a standard color chart that includes twenty color blocks. Two hundred and ninety outpatients had their urine samples assessed with this method as well as with the pyrogallol red test as a comparative study for quantitative measurement of protein concentrations. The new-type dipstick method exhibited good correlation with the results of the pyrogallol red test, especially in the range of protein concentrations from 50 mg/dl to 400 mg/dl, showing the linear equation of "y (Pyrogallol red) = 10.5 + 0.99 x (Dipstick) (r = 0.91, P < 0.01)". Although there was good correlation with the pyrogallol red test at higher concentrations from 400 mg/dl to 1,000 mg/dl, the dipstick method tended to exhibit lower concentrations than those indicated by the counterpart method. The rate of consistency between observers was quite high. This new-type dipstick method will offer a reliable method for patients or their family to assess their protein excretion in the urine every 24 hours at home using a portable urine sampling device.

[Changes in insulin sensitivity after weight loss in hypertensive patients with obesity]

To assess the role of insulin resistance in the hypotensive effect of weight loss, insulin sensitivity was examined by the euglycemic insulin clamp method in 15 untreated obese hypertensive patients with a body mass index of 25 kg/m2 or greater (4 men and 11 women, with a mean age of 53.4 years) before and 4 weeks after being placed on a low-calorie diet of 800 Cal/day with mild exercise. Body weight decreased by 11.0% (from 74.3 +/- 3.8 to 66.1 +/- 3.0 kg; p < 0.01) with a concomitant fall of mean blood pressure from 122.5 +/- 2.3 to 108.6 +/- 2.4 mmHg (p < 0.01). Glucose infusion rate (GIR), as an index of insulin sensitivity, was significantly increased by 54.3% (from 3.66 +/- 2.4 to 5.5 +/- 9.3 ml/kg/min; p < 0.01). Plasma levels of fasting blood sugar and insulin decreased significantly by 11.8% and 58.4%, respectively (both p < 0.01). The change in mean blood pressure showed a negative correlation with the change in GIR resulting from weight loss (r = -0.79, p < 0.05). These findings suggest that the hypotensive effect of weight loss in hypertensive patients with obesity is partly related to improvement of insulin sensitivity.

[Serum lipid states in elderly patients with acute myocardial infarction: comparison between patients aged 60 to 79 and 80 years and over]

Recently, the prevalence of acute myocardial infarction (AMI) in the elderly patients has increased. The clinical features have not been extensively studied, so this study attempted to clarify the clinical course and prognosis of elderly patients with AMI. The patients were divided into two groups, those over 80 years old and those between 60 and 79 years old. The clinical symptoms, electrocardiographic findings, complications, and short-term prognosis were compared. The serum lipid levels were compared between the AMI groups and age-matched control groups consisting of subjects without sclerotic heart disease. There was no significant difference in clinical symptoms between the two groups, electrocardiographic findings, incidence of complications, and mortality. The total cholesterol and LDL cholesterol levels, and atherogenic index were significantly higher in the 60-79 years old AMI group, but no significant difference was observed in the 80 years and over AMI group compared to the control group. The HDL cholesterol level of the 60-79 years old AMI group was significantly lower, but no significant difference was observed in the 80 years and over group. There was no significant difference in triglyceride level in either AMI group. Therefore, in patients aged 60-79 years hyperlipidemia is a risk factor for ischemic heart disease, but the relationship between serum lipid and AMI is not positively established in patients older than 80 years. These results suggest that the significance of hyperlipidemia in patients over 80 years old should be reconsidered.

Effects of diet high in medium-chain triglyceride on plasma ketone, glucose, and insulin concentrations in enterectomized and normal rats

The effects of dietary medium-chain triglyceride (MCT) on the concentration of plasma ketone bodies in enterectomized and normal rats were examined, together with the effects on plasma glucose, plasma immuno-reactive insulin, and liver function. Four groups of enterectomized rats and four groups of normal rats were fed experimental diets containing 0, 6, 11, or 21% of MCT by weight for 6 days. All animals including normal rats received meal-feeding for 3 h once a day. On day 3, concentration of plasma ketone bodies in enterectomized rats increased dose-dependently with dietary MCT and the level was higher than that in normal rats. However, all the values in enterectomized rats never exceeded 2 mM, the maximum physiological concentration. In contrast, plasma glucose in the enterectomized rats showed a tendency to decrease more clearly and dose-dependently with dietary MCT, followed by a marked increase of insulin secretion compared with those in normal rats. On the final day, no significant differences in the results of liver function tests were observed among these groups. These results indicate that the MCT-induced ketosis was within an acceptable range, and dietary MCT is useful for the suppression of increase in plasma glucose following a surgical operation without any disadvantageous effects on liver function.

High-density culture of FM-3A cells using a bioreactor with an external tangential-flow filtration device

A novel bioreactor system developed for high-density cultures of suspended mammalian cells is described using a tangential-flow filtration device outside the culture vessel to separate viable cells from spent medium. The filtration device is based on thin porous microfiltration membranes with a pore size of 0.20-0.65 microns. Because cells have a diameter of about 10-20 microns, they cannot permeate these membranes with the spent medium. So, allowing a perfusion culture to be created using this system. In most membrane filtration systems, clogging of the membranes has made long-term operation difficult. In this system, however, high pressure is not applied directly to the membrane, thus minimizing clogging. Also, clogging of the membrane was prevented by washing the membrane surface once a day, and increasing the membrane surface area. With this system, FM-3A cells were cultured and maintained at a high density of 3.0 x 10(7) cells/ml for two weeks, and a continuous culture was supported for as long as 34 days.

Induction of micronucleated erythrocytes by recombinant human erythropoietin

Induction of micronucleated erythrocytes by a recombinant human erythropoietin (rhEPO) was examined using both in vitro and in vivo test systems. A small, significant and dose-related increase in the frequency of micronucleated polychromatic erythrocytes (MNPCE) in bone marrow of mice administered i.p. with 12,500-50,000 IU/kg rhEPO was induced at 48 h sampling time. A clear positive dose--response relationship and significant increase in the frequency of micronucleated reticulocytes (MNRET) in peripheral blood of mice administered i.p. with 400-50,000 IU/kg rhEPO was noted at 48, 72 and 96 h sampling times. Conversely, in bacterial reverse mutation tests, no noticeable increase of auxotrophic revertants was observed in Salmonella typhimurium, TA100, TA98, TA1535, TA1537, or Escherichia coli, WP2 uvrA-, by treatment with 188-6000 IU/plate of rhEPO, with or without S9 mix. Furthermore, rhEPO at 750-6000 IU/ml did not induce chromosomal aberrations in vitro in CHL cells or human peripheral blood lymphocytes in a direct method nor in a metabolic activation method. Moreover, chromosomal aberrations were not detected in bone marrow cells of CD-1 male mice, even at high rhEPO concentrations (100,000 IU/kg) in vivo. Consequently, it was concluded that errors in the process of enucleation or differentiation of the erythrocytes should be equally considered as possible mechanisms for the increased frequencies of MNPCE and MNRET alongside induction of DNA damage or errors in the process of DNA repair.

Comparative studies in induction of micronuclei by three genetically recombinant and urinary human erythropoietins

Comparative studies on the induction of micronucleated erythrocytes by three recombinant human erythropoietins (rhEPOs) such as epoetin alpha, epoetin beta, and SNB-5001, and by urinary human EPO (uhEPO) were carried out in vivo. Small but significant increases in the frequency of micronucleated polychromatic erythrocytes (MNPCEs) in bone marrow of mice following a single intraperitoneal (i.p.) administration of each of the three rhEPOs and uhEPO (25,000 IU/kg) were observed at the 48 h sampling time. Clear, significant increases in the frequency of micronucleated reticulocytes (MNRETs) in the peripheral blood of mice similarly treated with the four hEPOs at 50,000 IU/kg were noted at the 48, 72 and 96 h sampling times. When mice were dosed with 50,000 IU/kg of each of the hEPOs once each day for 6 days and micronucleus preparations were made 24 h after the last administration, micronucleus induction in the bone marrow was not clearly demonstrated. As before, MNRETs in these mice were significantly induced in all cases. Consequently, it was concluded that induction of MNPCEs and MNRETs was a common characteristic of both native and genetically recombinant EPO.

Genotoxicity of genetic recombinant human erythropoietin in a novel test system

The nude (athymic) mouse was used as a novel test system for the evaluation of genotoxicity of genetic recombinant human erythropoietin (rhEPO). A fibroblast cell line derived from the kidneys of baby hamsters, BHK-21, or a subclone of BHK-21 transfected with an expression vector containing the human EPO gene, named BXE cells, were implanted in nude mice. The concentration of EPO in the plasma of mice bearing BXE increased in relation to the increase in the weight of the tumor formed from growth of BXE cells. Increased values of hematocrit (Ht), ratio of reticulocytes to erythrocytes (RET ratio) and the number of red blood cells in mice bearing BXE indicated that excessive hematopoiesis was occurring in the host. However, the concentrations of EPO in the plasma of the mice bearing BHK-21 did not increase in relation to the cell mass and consequently the Ht values and RET ratios in these mice were not affected. Marked increases in the frequencies of micronucleated polychromatic erythrocytes (MNPCE) and micronucleated RET (MNRET) were noted in the mice bearing BXE, although no chromosomal aberrations were found in the spleen and marrow cells of the same mice. The increased levels of RET, MNRET and MNPCE seemed to result from acceleration of erythroblastic maturation and proliferation by rhEPO. It is, therefore, concluded that errors in the processes of enucleation or differentiation of erythrocytes should be equally considered as possible mechanisms alongside errors in genetic repair processes for the increased frequencies of MNPCE and MNRET.

Adjuvant active specific immunotherapy for human colorectal cancer: 6.5-year median follow-up of a phase III prospectively randomized trial

PURPOSE

Patients with colon or rectal cancer were entered onto a prospectively randomized, controlled clinical trial of active specific immunotherapy (ASI) with an autologous tumor cell-bacillus Calmette-Guérin (BCG) vaccine. We investigated whether ASI could improve disease-free status and survival.

PATIENTS AND METHODS

Ninety-eight patients with Dukes' stage B2-C3 colon or rectal cancer were randomized into groups treated by resection alone or resection plus ASI. Eighty patients met all eligibility criteria. All patients with rectal cancer were to receive 50 Gy of pelvic irradiation. Analysis of distribution of survival and disease-free survival was made on all eligible patients until December 31, 1990.

RESULTS

As a single study, no statistically significant differences were detected in survival or disease-free survival for all 80 eligible patients. However, since it was recognized at the outset that there were treatment differences, in that rectal cancer patients were to receive postimmunotherapy radiation, it was considered that a cohort analysis of the colon and rectal cancer patients might be informative. With a median follow-up of 93 months, there is a significant improvement in survival (two-sided P = .02; hazards ratio, 3.97) and disease-free survival (two-sided P = .039; hazards ratio, 2.67) in all eligible colon cancer patients who received ASI. With a median follow-up of 58 months, no benefits were seen in patients with rectal cancer who received ASI.

CONCLUSION

This study suggests that ASI may be beneficial to patients with colon cancer.

[Statistical observation of crowns and bridges in Matsumoto Dental College]

A study was made of 11,425 crowns and 2,385 bridges which had been fabricated for 5,588 patients at the Prosthetic Clinic of Matsumoto Dental College during the fourteen-year period, from January 1973 to December 1986. Some of the results were as follows: 1. 753 patients, 1,585 crowns and 372 bridges in 1983 were the most numerous in all the survey years. 2. The rate of vital teeth of crowns has increased from 1984. 3. Of crowns, 22.1% and of bridge retainers, 22.3% were fabricated as porcelain fused to metal crown in 1985. 4. The rate of resin facing crowns of crowns and bridge retainers increased sharply in 1986. 5. Of crowns, 19.0% and of bridge retainers, 30.5% were fabricated as partial coverage crowns in 1986. 6. The rate of more than 5-unit bridges increased from 1982 to 1985.