Protective role of podocyte autophagy against glomerular endothelial dysfunction in diabetes

To examine the cell-protective role of podocyte autophagy against glomerular endothelial dysfunction in diabetes, we analyzed the renal phenotype of tamoxifen (TM)-inducible podocyte-specific Atg5-deficient (iPodo-Atg5^-/-) mice with experimental endothelial dysfunction. In both control and iPodo-Atg5^-/- mice, high fat diet (HFD) feeding induced glomerular endothelial damage characterized by decreased urinary nitric oxide (NO) excretion, collapsed endothelial fenestrae, and reduced endothelial glycocalyx. HFD-fed control mice showed slight albuminuria and nearly normal podocyte morphology. In contrast, HFD-fed iPodo-Atg5^-/- mice developed massive albuminuria accompanied by severe podocyte injury that was observed predominantly in podocytes adjacent to damaged endothelial cells by scanning electron microscopy. Although podocyte-specific autophagy deficiency did not affect endothelial NO synthase deficiency-associated albuminuria, it markedly exacerbated albuminuria and severe podocyte morphological damage when the damage was induced by intravenous neuraminidase injection to remove glycocalyx from the endothelial surface. Furthermore, endoplasmic reticulum stress was accelerated in podocytes of iPodo-Atg5^-/- mice stimulated with neuraminidase, and treatment with molecular chaperone tauroursodeoxycholic acid improved neuraminidase-induced severe albuminuria and podocyte injury. In conclusion, podocyte autophagy plays a renoprotective role against diabetes-related structural endothelial damage, providing an additional insight into the pathogenesis of massive proteinuria in diabetic nephropathy.

Protein O-GlcNAcylation Is Essential for the Maintenance of Renal Energy Homeostasis and Function via Lipolysis during Fasting and Diabetes

BACKGROUND

Energy metabolism in proximal tubular epithelial cells (PTECs) is unique, because ATP production largely depends on lipolysis in both the fed and fasting states. Furthermore, disruption of renal lipolysis is involved in the pathogenesis of diabetic tubulopathy. Emerging evidence suggests that protein O-GlcNAcylation, an intracellular nutrient-sensing system, may regulate a number of metabolic pathways according to changes in nutritional status. Although O-GlcNAcylation in PTECs has been demonstrated experimentally, its precise role in lipolysis in PTECs is unclear.

METHODS

To investigate the mechanism of renal lipolysis in PTECs-specifically, the role played by protein O-GlcNAcylation-we generated mice with PTECs deficient in O-GlcNAc transferase (Ogt). We analyzed their renal phenotypes during ad libitum feeding, after prolonged fasting, and after mice were fed a high-fat diet for 16 weeks to induce obesity and diabetes.

RESULTS

Although PTEC-specific Ogt-deficient mice lacked a marked renal phenotype during ad libitum feeding, after fasting 48 hours, they developed Fanconi syndrome-like abnormalities, PTEC apoptosis, and lower rates of renal lipolysis and ATP production. Proteomic analysis suggested that farnesoid X receptor-dependent upregulation of carboxylesterase-1 is involved in O-GlcNAcylation's regulation of lipolysis in fasted PTECs. PTEC-specific Ogt-deficient mice with diabetes induced by a high-fat diet developed severe tubular cell damage and enhanced lipotoxicity.

CONCLUSIONS

Protein O-GlcNAcylation is essential for renal lipolysis during prolonged fasting and offers PTECs significant protection against lipotoxicity in diabetes.

Role of dietary amino acid balance in diet restriction-mediated lifespan extension, renoprotection, and muscle weakness in aged mice

Extending healthy lifespan is an emerging issue in an aging society. This study was designed to identify a dietary method of extending lifespan, promoting renoprotection, and preventing muscle weakness in aged mice, with a focus on the importance of the balance between dietary essential (EAAs) and nonessential amino acids (NEAAs) on the dietary restriction (DR)‐induced antiaging effect. Groups of aged mice were fed ad libitum, a simple DR, or a DR with recovering NEAAs or EAAs. Simple DR significantly extended lifespan and ameliorated age‐related kidney injury; however, the beneficial effects of DR were canceled by recovering dietary EAA but not NEAA. Simple DR prevented the age‐dependent decrease in slow‐twitch muscle fiber function but reduced absolute fast‐twitch muscle fiber function. DR‐induced fast‐twitch muscle fiber dysfunction was improved by recovering either dietary NEAAs or EAAs. In the ad libitum‐fed and the DR plus EAA groups, the renal content of methionine, an EAA, was significantly higher, accompanied by lower renal production of hydrogen sulfide (H₂S), an endogenous antioxidant. Finally, removal of methionine from the dietary EAA supplement diminished the adverse effects of dietary EAA on lifespan and kidney injury in the diet‐restricted aged mice, which were accompanied by a recovery in H₂S production capacity and lower oxidative stress. These data imply that a dietary approach could combat kidney aging and prolong lifespan, while preventing muscle weakness, and suggest that renal methionine metabolism and the trans‐sulfuration pathway could be therapeutic targets for preventing kidney aging and subsequently promoting healthy aging.

Impact of obesity on annual medical expenditures and diabetes care in Japanese patients with type 2 diabetes mellitus

AIMS/INTRODUCTION

Diabetes and obesity are important health and economic concerns. We investigated the influence of obesity on diabetes control, the annual medical expenditures and medications in Japanese patients with type 2 diabetes who were relatively lean in comparison with those in Western countries.

MATERIALS AND METHODS

A total of 402 Japanese patients with type 2 diabetes were enrolled and their annual medical expenditures investigated. Obesity was defined as body mass index ≥25 kg/m2 , according to the obesity classifications from the Japan Society for the Study of Obesity.

RESULTS

A total of 165 patients (41.0%) were classified as obese. The obese group was younger, had poor glycemic control and higher frequency of hypertension than the non-obese group. The median total annual medical expenditures for all participants was ¥269,333 (interquartile range ¥169,664-437,437), which was equivalent to approximately $US2,450. The annual medical expenditure was significantly higher in patients with obesity than in non-obese patients (P < 0.001). This difference was mainly attributed to the annual expenditures for medication and hospitalization. In particular, the medication expenditures and the average number of drug classes for hyperglycemia and hypertension were significantly higher in the obese group.

CONCLUSIONS

Japanese patients with type 2 diabetes and obesity had higher annual medical expenditures and a larger number of medications, but their diabetes control care was insufficient in comparison with those without obesity. Further studies are required to assess the effect of reducing bodyweight on diabetes control and costs.

Overexpression of acetyl CoA carboxylase β exacerbates podocyte injury in the kidney of streptozotocin-induced diabetic mice

A single nucleotide polymorphism (SNP) within the acetyl CoA carboxylase (ACC) β gene (ACACB), rs2268388, has been shown to be associated with susceptibility to development of proteinuria in patients with type 2 diabetes. To investigate the biological roles of ACCβ in the pathogenesis of diabetic nephropathy, we examined the effects of overexpression of ACACB using podocyte-specific ACACB-transgenic mice or ACACB-overexpressing murine podocytes. Podocyte-specific ACACB-transgenic mice or littermate mice were treated with streptozotocin (STZ) to induce diabetes, and 12 weeks after induction of diabetes, we examined the expression of podocyte markers to evaluate the degree of podocyte injury in these mice. We also examined the effects of ACCβ on podocyte injury in ACACB- or LacZ-overexpressing murine podocytes. Podocyte-specific ACACB overexpression did not cause visible podocyte injury in non-diabetic mice. In STZ-induced diabetic mice, ACACB-transgenic mice showed a significant increase in urinary albumin excretion, accompanied by decreased synaptopodin expression and podocin mislocalization in podocytes, compared with wild-type mice. In cultured murine podocytes, overexpression of ACACB significantly decreased synaptopodin expression and reorganized stress fibers under high glucose conditions, but not in normal glucose conditions. The decrease of synaptopodin expression and reorganized stress fibers observed in ACACB overexpressing cells cultured under high glucose conditions was reversed by a treatment of 5-aminoimidazole-4-carboxamide-1-beta-4-ribofuranoside (AICAR), activator of AMP-activated protein kinase (AMPK). The excess of ACCβ might contribute to exacerbation of podocyte injury in the kidney of an animal model for diabetes mellitus, and the AMPK/ACCβ pathway may be a novel therapeutic target for the prevention of diabetes-related podocyte injury.

[Intraoperative right-to-left shunting induced by supine position in simultaneous lung resection with repair of atrial septal defect]

This report describes the case of a 49-year-old woman, who was suffered severe hypoxemia attributable to right-to-left shunting through an atrial septal defect (ASD) during the combined surgery for lung cancer and ASD in supine position. Right-to-left shunting has been reported to occur after lung resection but not during it. According to our continuous measurement of pulmonary arterial pressure and oxygen saturation, changes in hemodynamics during lobectomy in supine position was supposed to differ from that in lateral position, which may contribute to right-to-left shunting. A combined lung resection with heart surgery was performed safely and resulted in preventing postoperative complications induced by ASD.

[Preoperative assessment of myocardial ischemia in thoracic surgery for lung cancer]

BACKGROUND

Morbidity of myocardial ischemia in the thoracic surgery for lung cancer has been reported in the literatures, although, the risk of myocardial ischemia is not well identified preoperatively.

OBJECTIVES

The aim of this study was to describe the prevalence of severe coronary stenosis in the thoracic surgery for lung cancer.

METHODS

From January 2004 to December 2006, data were collected concerning 175 consecutive patients underwent lung resection for lung cancer. Prior to the surgery, we performed coronary angiography on the patients with either ischemic change in the exercise electrocardiogram (ECG) testing or comorbid conditions (current or previous smoking, hypertention, diabetes mellitus, hyperlipidemia or history of chest pain).

RESULTS

Fifty-eight (33%) patients underwent coronary angiography. Coronary stenosis was detected in 19 patients (10.9%), including 6 patients (3.4%) with severe stenosis. These 6 patients received percutaneous coronary intervention or coronary artery bypass grafting prior to the lung resection, which resulted in no incidence of perioperative myocardial ischemia. Three of 6 patients with severe stenosis were negative for ischemic changes in exercise ECG testing.

CONCLUSION

The prevalence of severe coronary stenosis is 3.4%, which is supposed to indicate the risk of perioperative myocardial ischemia in the thoracic surgery for lung cancer.

Genetic variations associated with diabetic nephropathy and type II diabetes in a Japanese population

Genetic susceptibility plays an important role in the pathogenesis of diabetic nephropathy and type II diabetes. To identify the genetic polymorphisms associated with diabetic nephropathy and type II diabetes, we performed a genome-wide association study using single-nucleotide polymorphisms as genetic markers. We also analyzed polymorphisms within the genes encoding for the renin-angiotensin system that were considered as candidate genes for diabetic nephropathy susceptibility and the transcription factor 7-like 2 (TCF7L2) as a candidate for type II diabetes, in a large cohort of a Japanese population. A genome-wide association study identified SLC12A3 and engulfment and cell motility 1 gene as the new candidates for diabetic nephropathy and transcription factor-activating protein 2beta as a novel susceptibility gene for type II diabetes; this observation was based on the significant association between the polymorphisms within the genes and the corresponding diseases (P<0.0001). Further, we discovered that the genes encoding the angiotensin-converting enzyme, angiotensinogen, and angiotensin II type I receptor have a significant combinational effect on conferring susceptibility to diabetic nephropathy. Furthermore, TCF7L2 that has been reported as a convincing susceptibility gene for type II diabetes in Caucasian populations was also shown to be associated with type II diabetes in a Japanese population. These genes could be considered as strong susceptibility genes for diabetic nephropathy and type II diabetes in the Japanese, although the new candidates that have been identified by genome-wide screening need to be examined in greater detail by several replication studies.

Pulmonary-renal syndrome, diffuse pulmonary hemorrhage and glomerulonephritis, associated with Wegener's granulomatosis effectively treated with early plasma exchange therapy

We present a case of a 38-year-old Japanese man with Wegener's granulomatosis complicated with pulmonary-renal syndrome, i.e., diffuse pulmonary hemorrhage and rapidly progressive renal glomerulonephritis. As this is a life-threatening condition, we promptly initiated plasma exchange with intravenous methylprednisolone therapy. Diffuse pulmonary hemorrhage and renal failure were markedly improved. This case merits presentation because there are few clinical studies of the treatment of Wegener's granulomatosis with pulmonary-renal syndrome, particularly with pulmonary hemorrhage.

Combinational effect of genes for the renin-angiotensin system in conferring susceptibility to diabetic nephropathy

To elucidate the role of the renin-angiotensin system (RAS) in diabetic nephropathy, we examined the association between diabetic nephropathy in a large cohort of Japanese type 2 diabetic patients and polymorphisms within the genes that encode angiotensin-converting enzyme (ACE), angiotensinogen (AGT) and angiotensin II receptor type 1 (AGTR1). Single nucleotide polymorphisms (SNPs) within these genes were genotyped using invader assay in 747 nephropathy cases and 557 control subjects. Eight SNPs within the ACE gene were significantly associated with diabetic nephropathy (P<0.05), including five SNPs in almost complete linkage disequilibrium to the insertion/deletion polymorphism in the 16th intron (P=0.01, odds ratio =1.34, 95% CI 1.07-1.69). Three SNPs within the AGT, including M235T and one SNP in the AGTR1, were also significantly associated with nephropathy (M235T P=0.01, odds ratio =0.74, 95% CI 0.59-0.94). In addition, we found that the allelic mRNA expression corresponding to the 235M allele was significantly higher than that for the 235T allele in normal kidney tissues. Furthermore, we found a significant additional effect of these three genes by a step-wise logistic regression analysis (final empirical P value =0.00005). We concluded that RAS gene polymorphisms may contribute to the susceptibility to diabetic nephropathy in type 2 diabetes.

Familial pseudohyperkalemia: a rare cause of hyperkalemia

A previously healthy 19-year-old girl was admitted to our hospital because of hyperkalemia. Pseudohyperkalemia was diagnosed because there was a marked difference between levels of serum and plasma potassium. Her plasma potassium level was markedly increased after 6-hour in vitro incubation of blood at room temperature, suggesting excessive potassium release from red blood cells without coagulation. The plasma potassium levels of the patient and her father were markedly elevated in blood specimens incubated in vitro at 4 degrees C, but not at 37 degrees C. These data indicated pseudohyperkalemia syndrome caused by abnormal leakage of potassium from red blood cells at the lower temperatures.

Formation of PCDDs and PCDFs during the combustion of polyvinylidene chloride

In laboratory-scale combustion of polyvinylidene chloride (PVDC) with a quartz tubular furnace designed and fabricated to provide the desired combustion temperature and mixing state of combustion gas with air, it was found that at 800 degrees C or higher the level of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans [corrected] (PCDDs/PCDFs) resulting from PVDC combustion was no higher than that from heating air alone, and thus far below the levels which resulted from PVDC combustion at 750 degrees C or lower. The results provide the first laboratory confirmation of the relation between PVDC incineration temperature and PCDD/PCDF formation, and of the primary importance of high temperature, turbulence for mixing between air and combustion gas, and sufficient residence time, as governing factors for the minimization of PCDD/PCDF formation in municipal solid waste incinerators.

Early and late recurrence after gastrectomy for gastric carcinoma. Univariate and multivariate analyses

BACKGROUND

To the authors' knowledge, there are few studies regarding the predictors of early and late recurrence after gastrectomy for gastric carcinoma, and it is unknown whether prognostic factors can be applied to the timing of recurrence. The current study analyzed patients who died of recurrent gastric carcinoma and clarified histopathologic indicators associated with early and late recurrence.

METHODS

The study included 138 patients who died of recurrent gastric carcinoma after gastrectomy that was performed in the Department of Surgery I, Oita Medical University, between 1982-1995. Clinicopathologic findings were compared between 104 patients who died within 2 years after gastrectomy (early recurrence group) and 34 patients who died > 2 years after gastrectomy (late recurrence group). Multivariate analysis was performed to determine the independent factors correlated with the timing of recurrence.

RESULTS

When compared with the late recurrence group, the early recurrence group was characterized by a tumor size >/= 5 cm (92% in the early recurrence group vs. 74% in the late recurrence group), positive lymphatic invasion (64% vs. 38%), extended lymph node metastasis (73% vs. 35%), Stage III or IV disease (87% vs. 62%), and limited lymph node dissection (32% vs. 3%). The mean survival time was influenced by the lymphatic invasion (P < 0.01), vascular invasion (P < 0.05), level of lymph node metastasis (P < 0.01), stage of disease (P < 0.01), and extent of lymph node dissection (P < 0.01). On multivariate analysis, survival time was found to be associated independently with the stage of disease (Stage I, II vs. Stage III, IV) or the level of lymph node metastasis (N0, N1 vs. N2, N3).

CONCLUSIONS

The stage of disease and level of lymph node metastasis were found to be the most significant factors independently associated with the survival time after gastrectomy for gastric carcinoma. Patients with more advanced stage of disease (Stage III, IV) or those with extended lymph node metastasis (N2, N3) frequently died of recurrence within 2 years after gastrectomy.

Early and late recurrence after gastrectomy for gastric carcinoma. Univariate and multivariate analyses

BACKGROUND

To the authors' knowledge, there are few studies regarding the predictors of early and late recurrence after gastrectomy for gastric carcinoma, and it is unknown whether prognostic factors can be applied to the timing of recurrence. The current study analyzed patients who died of recurrent gastric carcinoma and clarified histopathologic indicators associated with early and late recurrence.

METHODS

The study included 138 patients who died of recurrent gastric carcinoma after gastrectomy that was performed in the Department of Surgery I, Oita Medical University, between 1982-1995. Clinicopathologic findings were compared between 104 patients who died within 2 years after gastrectomy (early recurrence group) and 34 patients who died > 2 years after gastrectomy (late recurrence group). Multivariate analysis was performed to determine the independent factors correlated with the timing of recurrence.

RESULTS

When compared with the late recurrence group, the early recurrence group was characterized by a tumor size >/= 5 cm (92% in the early recurrence group vs. 74% in the late recurrence group), positive lymphatic invasion (64% vs. 38%), extended lymph node metastasis (73% vs. 35%), Stage III or IV disease (87% vs. 62%), and limited lymph node dissection (32% vs. 3%). The mean survival time was influenced by the lymphatic invasion (P < 0.01), vascular invasion (P < 0.05), level of lymph node metastasis (P < 0.01), stage of disease (P < 0.01), and extent of lymph node dissection (P < 0.01). On multivariate analysis, survival time was found to be associated independently with the stage of disease (Stage I, II vs. Stage III, IV) or the level of lymph node metastasis (N0, N1 vs. N2, N3).

CONCLUSIONS

The stage of disease and level of lymph node metastasis were found to be the most significant factors independently associated with the survival time after gastrectomy for gastric carcinoma. Patients with more advanced stage of disease (Stage III, IV) or those with extended lymph node metastasis (N2, N3) frequently died of recurrence within 2 years after gastrectomy.

Early and late recurrence after gastrectomy for gastric carcinoma. Univariate and multivariate analyses

BACKGROUND

To the authors' knowledge, there are few studies regarding the predictors of early and late recurrence after gastrectomy for gastric carcinoma, and it is unknown whether prognostic factors can be applied to the timing of recurrence. The current study analyzed patients who died of recurrent gastric carcinoma and clarified histopathologic indicators associated with early and late recurrence.

METHODS

The study included 138 patients who died of recurrent gastric carcinoma after gastrectomy that was performed in the Department of Surgery I, Oita Medical University, between 1982-1995. Clinicopathologic findings were compared between 104 patients who died within 2 years after gastrectomy (early recurrence group) and 34 patients who died > 2 years after gastrectomy (late recurrence group). Multivariate analysis was performed to determine the independent factors correlated with the timing of recurrence.

RESULTS

When compared with the late recurrence group, the early recurrence group was characterized by a tumor size >/= 5 cm (92% in the early recurrence group vs. 74% in the late recurrence group), positive lymphatic invasion (64% vs. 38%), extended lymph node metastasis (73% vs. 35%), Stage III or IV disease (87% vs. 62%), and limited lymph node dissection (32% vs. 3%). The mean survival time was influenced by the lymphatic invasion (P < 0.01), vascular invasion (P < 0.05), level of lymph node metastasis (P < 0.01), stage of disease (P < 0.01), and extent of lymph node dissection (P < 0.01). On multivariate analysis, survival time was found to be associated independently with the stage of disease (Stage I, II vs. Stage III, IV) or the level of lymph node metastasis (N0, N1 vs. N2, N3).

CONCLUSIONS

The stage of disease and level of lymph node metastasis were found to be the most significant factors independently associated with the survival time after gastrectomy for gastric carcinoma. Patients with more advanced stage of disease (Stage III, IV) or those with extended lymph node metastasis (N2, N3) frequently died of recurrence within 2 years after gastrectomy.

Evaluation of inner ear histology and auditory brainstem response in Wriggle Mouse Sagami

Wriggle Mouse Sagami (WMS) is a spontaneous mutant strain with neuroepithelial defects. These animals are characterized by abnormal movements linked to an autosomal recessive gene. To determine the association between inner ear histology and hearing ability, we assayed these characteristics in mice homozygous and heterozygous for the mutation, as well as in wild-type animals. In homozygotes, the cochlea and saccule degenerated 3 months after birth. Beginning at 3 months of age, and progressing in an age-dependent manner, the organ of Corti disappeared and the number of spiral ganglion cells decreased, starting at the basal turn and moving toward the apical turn. The sensory epithelium became atrophic in the saccule. Three-month-old heterozygotes demonstrated degeneration in the cochlea, not in the saccule. No obvious auditory brainstem evoked response (ABR) was observed at any frequency in homozygotes aged 1 month and older. In contrast, the heterozygotes retained some hearing acuity until the age of 1 month, after which they became deaf. These findings suggest that WMS mice may provide a good model that will be useful in identifying deafness genes in humans.

Feline coronavirus participation in diarrhea of cats

Fecal samples were examined for viruses participated in gastrointestinal disorders of cats, especially focusing on feline coronavirus (FCoV) by a reverse transcriptase-polymerase chain reaction assay. It was found that a primary viral pathogen was feline panleukopenia parvovirus (FPLV; 28.5% of the positive rate) and the secondary was FCoV (10.7%). Commonly reported clinical signs of cats of which feces were FCoV-positive were vomiting, diarrhea and dehydration with an exception of one serious case with concurrent FPLV infection.

Screening of patients with maternally transmitted diabetes for mitochondrial gene mutations in the tRNA[Leu(UUR)] region

To investigate the prevalence and clinical characteristics of diabetes mellitus caused by mitochondrial gene mutations in the tRNA[Leu(UUR)] region, a known 'hot spot' for pathogenic mutations, we screened 440 diabetic patients with diabetic mothers for 11 mitochondrial gene mutations reported in mitochondrial neuromuscular disorders; nucleotide pairs (np) 3250, 3251, 3252, 3254, 3256, 3260, 3271, 3291, 3302 and 3303 in addition to an A to G transition at np 3243. The dot-blot hybridization method using 32P-labelled sequence-specific oligonucleotides as probes was used. One subject carrying a T to C transition at np 3271 and seven carrying the A to G transition at np 3243 were identified, while none of the other diabetic patients screened had these mutations in the tRNA[Leu(UUR)] region. The patient with the 3271 mutation, a 39-year-old male, had excellent glycaemic control with diet alone and had neither hearing impairment nor symptoms suggesting mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS). Thus, among patients with maternally transmitted diabetes, the prevalence of the 3271 mutation was approximately one-seventh that of the 3243 mutation, and other mutations are even more rare in the mitochondrial tRNA[Leu(UUR)] region.

Cloning and characterization of the nucleoredoxin gene that encodes a novel nuclear protein related to thioredoxin

In a yeast artificial chromosome contig close to the nude locus on mouse chromosome 11, we identified a novel gene, nucleoredoxin, that encodes a protein with similarity to the active site of thioredoxins. Nucleoredoxin is conserved between mammalian species, and two homologous genes were found in Caenorhabditis elegans. The nucleoredoxin transcripts are expressed in all adult tissues examined, but restricted to the nervous system and the limb buds in Day 10.5-11.5 embryos. The nucleoredoxin protein is predominantly localized in the nucleus of cells transfected with the nucleoredoxin expression construct. Since the bacterially expressed protein of nucleoredoxin showed oxidoreductase activity of the insulin disulfide bonds with kinetics similar to that of thioredoxin, it may be a redox regulator of the nuclear proteins, such as transcription factors.

Prognostic significance of the p53 mutation in esophageal cancer

In the esophagus, alterations in the p53 tumor suppressor gene are associated with the development of preinvasive neoplastic lesions to invasive carcinoma. The role of p53 gene mutation in the progression of esophageal cancer still remains unclear. In this study, 82 DNA samples extracted from formalin-fixed, paraffin-embedded esophageal cancer tissues were analyzed for p53 mutation by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis. All the patients had been treated surgically and were Japanese. Exons 5 through 8 of the p53 gene were amplified in DNAs and the mutations detected in 28 cases (34%) did not correlate with tumor location, histopathologic classification, histologic depth of tumor invasion, lymph node involvement or clinical stage. Among 39 patients with stage 3 and 4 disease who had undergone radical esophageal resection, those with p53 mutation had a poorer prognosis, the two-year survival being 25.4% compared with 61.2% for those without p53 mutation (P<0.01). These results suggest that p53 gene mutations play an important role not only in the genesis but also the progression of human esophageal cancer.

Correction of the QT interval in children

We evaluated the usefulness of 11 formulas for correcting the QT interval in children, including the square root, cubic root, logarithmic, linear, exponential, and inverse formulas using the Mean-squared residual (MSR) values and Akaike Information Criterion (AIC) in 8,086 first-graders, 9,989 seventh-graders, and 5,786 tenth-graders. The subjects were divided into six groups according to age and sex. MSR and AIC values were lowest in all of the groups for the exponential formula (eQTc) and Fridericia's formula (fQTc). We then evaluated the relative usefulness of these two formulas by determining the optimal value for parameter k using the following exponential model: eQTc = (QT interval)/(RR interval)k. The best-fit value for k was different for each group. However, the tentative abnormal eQTc and fQTc values, determined by statistical analysis, were equivalent in all groups when 0.31 was used as the exponential parameter k. These results suggest that the exponential formula and Fridericia's formula are equally useful for screening for QT prolongation.

[Trace elements analysis of serum and cerebrospinal fluid with PIXE--effect of age and changes in parkinsonian patients]

The concentrations of Br, Cu, Fe, Se, Zn, Mg were determined by particle-induced X-ray emission (PIXE) in serum and cerebrospinal fluid (CSF) of 13 untreated, 7 L-dopa treated parkinsonian patients and 25 controls. There were significant positive correlations between serum concentrations and CSF concentrations of Br, Cu, Fe. The Cu/Zn ratio in the serum and the CSF/serum ratio of Br were significantly increased with age in normal controls. The mean CSF concentration of Mg in both treated and untreated parkinsonian patients was lower than in controls. PIXE is a valuable method for multielemental analysis of the serum and CSF.

Amino acid-induced responses in CNS neurons of normal mouse and Wriggle Mouse Sagami

Amino acid-induced responses and their regional heterogeneities in the motor cortical and hippocampal (CA1) neurons of normal mouse and Wriggle Mouse Sagami (WMS) were studied by conventional patch-clamp techniques. There were no differences in the current densities and EC50s of glutamate-, gamma-amino butyric acid (GABA)-, and glycine-induced responses between the two groups of mice. In both types of mice, the GABA-induced current density of cortical neurones was higher and EC50 was lower than in hippocampal neurones, whereas the responses induced by glycine and glutamate did not show any differences.

Oxygen-independent antimicrobial activity against Salmonella enteritidis of specially activated macrophage with living vaccine

Characteristics of peritoneal macrophages recovered from mice infected with two attenuated strains SER and Jena of Salmonella enteritidis were compared. Strong resistance against lethal infection with a virulent strain 116-54 of S. enteritidis was seen in a group of mice immunized with strain SER, but not in a group of mice immunized with strain Jena as well as in a control group. Peritoneal macrophages from mice immunized with strain SER showed an enhanced Salmonella-killing activity, an increased generation of O2- and an increased expression of Ia antigen on 7 to 14 days after infection when compared with those from mice immunized with strain Jena and thioglycollate(TG)-elicited macrophages as a control. The bacterial number of strain Jena in organs decreased more rapidly than that of strain SER after day 4 of infection. These observations suggest that the survival of an attenuated Salmonella bacilli at reticulo-endothelium is essential to increase of their activities of macrophages. Macrophages from mice injected with recombinant interferon(IFN)-gamma for 3 days induced the activated stage of the same characteristics as noted in activated macrophages from mice immunized with strain SER. Effect of oxygen intermediates (OI) scavengers such as superoxide dismutase and catalase on Salmonella-killing activity of activated macrophages was not seen at all. These results suggest that an increased generation of OI may be not primarily responsible for the ability to inhibit the intracellular growth of a virulent strain of S. enteritidis in macrophages activated by immunization with live, attenuated strains and injection with rIFN-gamma.

Mapping of the nu gene using congenic nude strains and in situ hybridization

The chromosomal location of the nu gene, which is responsible for hairlessness and athymus, was determined using six DNA markers (interleukin 3 [Il-3], Myhs, Acrb, Evi-2, Mpo, and Hox-2) on mouse chromosome 11. We constructed the high-resolution physical mapping of the six DNA markers on chromosome 11 by in situ hybridization using fluorescence-labeled cosmid probes. The results indicate the order of centromere-(41cM)-Il-3-(3cM)-Myhs- (4cM)-Acrb-(6cM)-Evi-2-(3cM)-Mpo- (5cM)- Hox-2. We have used congenic nude strains and examined which of the six DNA markers were derived from the original nude mouse. We found the Evi-2 locus is linked to the nu gene in all the informative, independent congenic nude strains. From these data, we could estimate the location of the nu gene, not only genetically but also physically within a region that spans approximately 17 megabases (9 cM) between the Acrb and Mpo genes.

[Clinical study of Pseudomonas aeruginosa isolated from the urine of patients with urinary tract infections]

We studied the characteristics of Pseudomonas aeruginosa isolated from the urine specimens of the patients with urinary tract infections (UTI), in the urological unit at Kitasato University Hospital, between April, 1989 and March, 1990. Pseudomonas aeruginosa was detected in 8.0% of the total urine specimens (1.1% from outpatients, 6.9% from inpatients). Serotype of Pseudomonas aeruginosa was F (33%), G (17%), M (14%) and others (36%). In sensitivity tests, imipenem (IPM) had the lowest MIC among 8 antimicrobial agents tested, which were imipenem, piperacillin, cefsulodin, ceftazidime, aztreonam, gentamicin, amikacin, and ofloxacin with 5.0%, 82.0%, 74.0%, 69.0%, 92.0%, 67.0%, 79.0% and 82.0% resistant strains, respectively. Bladder cancer was the most common underlying disease in the urological patients with Pseudomonas infection. Pseudomonas aeruginosa infection is still an annoying problem in UTI among compromised patients suffering from advanced urinary tract malignancies.

Intracellular fate of Mycobacterium leprae in cultured murine macrophages in 24-well trays

Mycobacterium leprae is an obligate intracellular parasite which grows within mononuclear phagocytes. In clinical cases, M. leprae reaches enormous numbers in the macrophage-rich granulomas of leprosy. Peritoneal macrophages from CBA mice were cultured in Waymouth medium containing fresh horse serum in Costar 3424 trays (24 wells, 16 mm in diameter) each containing 9 x 12 mm cover slips. This medium was supplemented with 0.5 micrograms/ml of cycloheximide. These cells were infected with M. leprae Thai-53 strain obtained by nude mice inoculation. Significant multiplication of the acid-fast bacilli in the macrophages was observed three weeks after inoculation. This experiment showed M. leprae mainly multiplied in cells and not by rephagocytization of M. leprae derived from destroyed cells.

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome XIII. No recovery of beta-hemolytic streptococci from pharynx of MCLS patients

Lack of recovery of beta-hemolytic streptococci from the throat of 80 patients finally diagnosed as mucocutaneous lymph node syndrome was again confirmed, although alpha-hemolytic streptococci were consistently isolated from all patients but one. The implications of these findings were discussed, particularly in terms of the possible role of Streptococcus pyogenes in the pathogenesis of this disease.

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. XII. Variable responses of platelets in MCLS seem to be explainable by streptococcal pyrogenic exotoxin

As a model system for mucocutaneous lymph node syndrome (MCLS), we have advocated and used mice which had been rendered tolerant to Streptococcus pyogenes-associated antigens by neonatal infection with group A beta-hemolytic streptococci, because these mice have shown a variety of peculiar bioimmunological characteristics bearing a striking resemblance to those of MCLS patients. The results of our current investigations reaffirmed the reliability of the animal model by indicating that mice subjected to neonatal infection with S. pyogenes, or inoculation with streptococcal pyrogenic exotoxin (SPE) in Freund's adjuvant, were perfect counterparts of patients with MCLS on account of their platelet activation and hyperaggregability in response to provocative treatment, which are familiar findings in this disease.

Residues of doxycycline and oxytetracycline in eggs after medication via drinking water to laying hens

Doxycycline (DOTC) and oxytetracycline (OTC) were dissolved in drinking water (0.5 g/l) and supplied to laying hens for 7 consecutive days. Eggs laid were collected daily during and after medication, and the antibiotic concentrations in the yolk and albumin were determined by the cup-plate method with Bacillus cereus var. mycoides ATCC 11778. The concentrations of both antibiotics were increased in yolk day by day with the advance in medication, reached peaks 2 days after withdrawal and then declined gradually. Mean peak concentrations in the yolk were 6.70 micrograms/g for DOTC and 1.42 micrograms/g for OTC. Peak concentrations in the albumin occurred in the middle stage of medication, where the mean values were 12.24 micrograms/g for DOTC and 1.03 micrograms/g for OTC. DOTC was detected in albumin until 24 days after withdrawal and for 2 days more in yolk than in albumin. OTC was detected in yolk until 9 days after withdrawal. The depletion period of OTC was shorter for the albumin, where the residue disappeared in all eggs 6 days after withdrawal. In spite of similarities between DOTC and OTC in structure, DOTC was deposited in higher concentrations and lasted for a longer period in eggs. This characteristic was considered due to its greater lipophilicity, closely correlated with oral absorption and tissue penetration.

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. IX. Quantitation by ELISA of streptococcal pyrogenic exotoxin in the serum of MCLS patients

In the present paper we describe the use of an enzyme-linked immunosorbent assay reinforced with an introduction of monoclonal antibody, for the detection and quantitation of streptococcal pyrogenic exotoxin (SPE) in the serum of patients with mucocutaneous lymph node syndrome (MCLS). The amount of SPE was usually at a high level, and its 100% incidence in patients' sera was proved whenever the assay was made on the day of admission, thereby showing a marked contrast to carefully matched control sera which failed to mediate any positive result. As for the change in detected amount of the toxin, a clear dichotomy was observed between the serum of gammaglobulin-treated patients and that of infants given aspirin; in the former the positive result turned to negative rapidly following the initiation of treatment coupled with a defervescence, while in the latter the reduction of SPE levels was scarcely monitored for as long as 17 days after the onset of illness. Quantitation of SPE might be an auxiliary test for the diagnosis of MCLS, because a considerable amount of SPE was assessed in a patient who developed characteristic huge coronary artery aneurysms following an illness which did not fulfill the diagnostic criteria. These findings support our speculation in relation to the certain role of S. pyogenes as an etiological agent for MCLS. The possible mechanisms of gammaglobulin treatment in reducing the prevalence of cardiovascular lesions and the duration of systemic inflammation are discussed.

Functional difference in monoamine transmitters in the behaviorally abnormal mouse mutant (wriggle mouse sagami)

A mutant mouse (wriggle mouse sagami, WMS) with neurological disorders was found in a colony of the BALB/c strain. The clinical signs included tremor, dystonia and involuntary movements. The concentrations of the neurotransmitter substances, noradrenaline (NA), dopamine (DA), 5-hydroxytryptamine (5-HT) and acetylcholine (ACh), were measured simultaneously with their metabolites in dissected brain regions by high-performance liquid chromatography with electrochemical detection. The turnover of 5-HT was significantly higher in the cerebral cortex, hippocampus, hypothalamus, midbrain and pons-medulla of WMS than of the genetic control, BALB/c. The intrastriatal DA and its metabolites, 3,4-dihydroxyphenylacetic acid and homovanillic acid were increased. However, there was no evidence to suggest an increase in turnover rate of this neurotransmitter. An increase in concentration of and decrease in turnover rate of NA were observed in the cerebellum of this mutant. These findings suggest that multiple disturbance of the neurotransmitter system was largely responsible for the manifestation of the clinical signs of WMS.

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. VIII. Immunological tolerance to S. pyogenes-associated antigens seems essential to induction of MCLS

In our previous studies, we attempted to show that new-born mice infected with an attenuated strain of Streptococcus pyogenes, and exposed to streptococcal antigens approximately one month later, failed to develop a humoral response to those antigens but were able to respond normally to other unrelated antigens. Since such immunological characteristics are identical to those of patients with the mucocutaneous lymph node syndrome (MCLS), the present studies were performed with the aim of assessing the antibody-forming activities of peripheral blood lymphocytes collected from MCLS patients. These lymphocytes were cultured in the presence of pokeweed mitogen, streptolysin-O and streptococcal C-polysaccharide, leading to their refractoriness to S. pyogenes-associated antigens coupled with normal responsiveness to unrelated antigens. The implication of such immunological responsiveness elicited from neonatal exposure to streptococcal antigens is discussed, particularly with reference to the induction of MCLS.

Induction of antimicrobial activity by antitumor substances from pine cone extract of Pinus parviflora Sieb. et Zucc

Pretreatment with two distinct antitumor substances extracted from pine cone of Pinus parviflora Sieb. et Zucc. protected mice from the lethal effects of E. coli infection. Intraperitoneal administration of these fractions transiently induced differentiation-inducing factor (DIF) with a peak at 1-2hr. The rapid decay of DIF activity from the peritoneal cavity was followed by polymorphonuclear cell (PMN) accumulation and enhancement of superoxide generation (assayed with luminol-dependent chemiluminescence (LDCL] by peritoneal exudate cells. The superoxide generation by adherent cells was similarly enhanced by pretreatment, but was only 10-20% of that of the peritoneal exudate cells. Fractions that showed comparable antitumor/antimicrobial activity were also obtained from seed shells and cones of other pine trees of Japanese and foreign origin. On the other hand, a neutral polysaccharide fraction from Pinus parviflora Sieb. et Zucc. that lacked any of these activities did not induce PMN accumulation, DIF activity or LDCL generation. The results suggest a significant role in PMN activation for the expression of antimicrobial activity induced by pine cone extracts.