Biased distribution of the branched-chain fatty acids in ceramides of vernix caseosa

The compositions of ester- and amide-linked fatty acids from ceramides of human vernix caseosa were described with emphasis on the distribution of the branched-chain fatty acid (BCFA). Two novel ceramides were isolated from vernix caseosa in the course of this study: the acylated type of esterified alpha-OH-hydroxyacid/sphingosine ceramide (Cer[EAS]) and nonacylated type of non-OH fatty acid/hydroxysphingosine ceramide (Cer[NH]). Their chemical structures were identified by nuclear magnetic resonance and chemical procedure. The Cer[EAS] was an acylceramide and consisted of the highest concentrations of ester- and amide-linked BCFA (62 and 67%, respectively). The iso- or anteiso-branching structures of the aliphatic chains were confirmed by the mass spectra of their picolinyl or pyrrolidide derivatives. As a whole, amide-linked fatty acids of ceramides 1-7 and Cer[NH] were normal types of straight-chain fatty acids with or without alpha- or omega-hydroxylation. The BCFA concentrations of amide-linked fatty acids in these ceramides (ceramides 1-7 and Cer[NH]) were low and less than 10%. The BCFA thus occurred exclusively in a novel acylceramide of Cer[EAS] in the vernix caseosa.

Effects of diisopropylamine dichloroacetate on proliferation and differentiation of normal human keratinocytes in vitro

We found that diisopropylamine dichloroacetate (DADA), known as a vasodilator, enhanced growth of keratinocytes in 4 days culture at 1-30 microg/ml, and such promoting effects of cell proliferation were reconfirmed by measuring DNA synthesis using [(3)H]thymidine incorporation. On the other hand, this substance enhanced synthesis of keratin K1, a potent marker of differentiation in keratinocytes, at 1-100 microg/ml in low calcium (0.1 mM) or high calcium medium (1. 25 mM). Moreover, the formation of cornified envelope, another potent marker of differentiation in keratinocytes, was also promoted by DADA at a concentration of 0.1-10 mM which includes valid concentration of DADA for the enhancement of keratin K1 formation (1-100 microg/ml: 0.05-0.5 mM DADA). These results indicate that DADA has a double function, enhancement of both proliferation and differentiation of cells, which could be linked to the turnover of skin epidermis. Furthermore, in order to analyze the effect of DADA on keratinocytes, we examined the effects of each component of this substance, diisopropylamine (DIA) and dichloroacetate (DCA), on keratinocytes. As the result of these investigations, evidence was found that DCA was effective on enhancement of cell growth, but DIA was ineffective. Moreover, we found that DCA was effective on keratinocyte differentiation by evaluating the enhancement of a differentiation marker, formation of cornified envelopes, within 10 mM, while DIA was not effective. Therefore, we concluded that only DCA was an active component of the DADA molecule for the proliferation and the differentiation of keratinocytes in vitro.

[Long-term follow-up study on sequelae of carbon monoxide poisoning; serial investigation 33 years after poisoning]

1. We examined 156 patients 33 years after CO poisoning occurred at the Miike Mikawa Mine, Fukuoka, Japan. The subjects were classified according to age as follows: between 55 and 59 years (n = 14), 60 and 69 years (n = 62), 70 and 79 years (n = 60), and 80 and 87 years (n = 18). The mean age was 69.2 years old. Concerning the duration of coma that occurred soon after the accident, 64 remained comatose from 0 to 6 hours, 46 from 6 to 12 hours and 46 from 12 to 48 hours. 2. Subjective symptoms were observed in 96.8% of the patients. Among them, forgetfulness was noted in 89.7%, followed by irritability in 66.7%, headache in 59.6%, insomnia in 55.8%, limb pain in 46.8%, dull head feeling in 42.9% and dizziness in 36.5%. 3. Intellectual disturbances were observed in 68.6% of the patients, including impression disturbance in 58.3%, memory disturbance in 51.9%, calculation disturbance in 63.5%, thinking disturbance in 61.5% and disorientation in 14.1%. 4. Apathy and disorder of volition and interest which were found in 72.4% were included in personality change because all symptoms persisted for many years. Personality change was classified as follows: weakness of emotion and will (hypobulia) in 54.4%, infantilism in 35.2%, hyperactive, talkactive and lack of inhibition in 18.5%, lack of self-possession and unstable temper in 9.6%, depression in 15.3%, neurosis in 7.6% and schizophrenic state in 2.5%. Among these symptoms of personality change, weakness of emotion and will and infantilism were conspicuous among the patients who remained in a coma for more than 6 hours soon after the accident but showed no relationship with age. 5. Neurological symptoms that were found in 48.7% of the patients were classified as sensory disturbance in 25.6%, peripheral nerve symptoms in 16.0%, pyramidal symptoms in 14.1%, ataxia and cranial nerve symptoms in 7.1%, paroxysmal symptoms in 6.4% and focal symptoms in 4.5%, extrapyramidal symptoms in 21.8% (Parkinsonism in 4.5%, tremor in 10.9% and muscle rigidity in 16.0%) and vegetative symptoms in 37.2%. 6. At the time of investigation, 5 CO poisoning patients were classified as serious cases (3.2%), 20 as comparatively serious (12.8%) medium-degree cases, 28 as comparatively mild (17.9%) medium-degree cases, 37 as comparatively serious (23.7%) mild cases, 42 as comparatively mild (26.9%) mild cases, 24 (15.4%) as having symptoms which were not problematic, and 24 (15.4%) as having symptoms that markedly worsened due to complication. 7. A total of 138 (88.4%) cases had complications were classified as follows: 78 cases (50.0%) of hypertension, 62 cases (39.7%) of cerebral infarction, 24 cases (15.4%) of cardiac disturbance, 21 cases (13.5%) of diabetes mellitus, 14 cases (9.0%) of hepatic disturbance and six cases of silicosis (3.8%). 8. Cranial MRI was carried out for 129 cases (82.7%). Of the abnormal findings identified, cerebral atrophy accounted for 72.0% (93 cases), including moderate and severe cases in 47.2% (61 cases), pallidum lesion for 37.9% (49 cases), lacunar infarction (including cerebral infarction) for 52.7% (68 cases), and hippocampal atrophy for 18.6% (24 cases). Many cases of cerebral atrophy and hippocampal atrophy were observed in patients who remained in the initial coma for more than 12 hours and were 80 years of age or old. The cases of pallidum lesion were observed in patients who remained in the initial coma for more than 6 hours, and no relationship with age was found. The other findings, cerebral atrophy and lacunar infarction showed a slight relationship with age. 9. Among the moderate and serious cases of intellectual disturbance, cerebral atrophy constituted to 62.5%, lacunar infarction 68.7% and pallidum lesion 50.0%. Among the moderate and serious cases of personality change, cerebral atrophy constituted 78.5%, lacunar infarction 35.0% and pallidum lesion 50.0%. Moreover, among extrapyramidal symptoms, pallidum lesion constituted 58.6%, cerebral atrophy 55.1% and lacun

[Plasma nicotinic acid levels in hemodialysis patients after the administration of niceritrol]

Lp(a) has recently begun to attract attention as a risk factor of atherosclerotic disease, especially of ischemic heart disease. The Lp(a) concentration in the serum was shown to be important for chronic hemodialysis patients who have high mortality due to cardiovascular disease. Nicotinic acid derivatives, which are recognized for their capacity to lower the serum Lp(a) concentration, are effective against a high Lp(a) concentration in hemodialysis patients. In this study, niceritrol which is a nicotinic acid derivative was tested on hemodialysis patients and healthy controls by investigating the serum nicotinic acid level. Serum nicotinic acid concentration was also measured by the severity of renal dysfunction of patients untreated by niceritrol. The blood nicotinic acid concentration in healthy controls (n = 4) was changed after 2 hrs by the administration of niceritrol from 9.8 +/- 1.4 ng/ml to 192.7 +/- 23.1 ng/ml then slowly decreased. Chronic hemodialysis patients who take niceritrol every day showed the highest nicotinic acid serum concentration (500-1,000 ng/ml) on the day without hemodialysis and the serum level decreased with dialysis for 4 hrs to 25-80%. There was no significant difference in the nicotinic acid level in the serum between healthy controls (n = 10), chronic glomerulonephritis patients (n = 7), chronic renal failure patients (n = 8) and chronic hemodialysis patients (n = 17). Lp(a) concentration in the serum, however, was increased with greater severity of renal dysfunction, The side effect was not observed in any cases administered niceritrol. These data suggest nicotinate derivatives are effective for hemodialysis patients. High nicotinic acid level in the serum after treatment with niceritrol was lowered by dialysis. It is plausible that the nicotinate level in patients without niceritrol treatment did not influence the Lp(a) concentration, because there was no increase in the nicotinate level of the serum even if the patients had renal dysfunction.

[Analysis of 209 PCB congeners by high separation gas chromatography/low resolution mass spectrometer]

All PCB congeners were analyzed by high separation gas chromatography/low resolution mass spectrometer, using 209 PCB congeners as standards. They were separated into 169 peaks, including 28 peaks containing 2 PCBs and 8 peaks containing 3 PCBs. The rice oil samples of Fukuoka and Taiwan Poisonings were analyzed for PCB congeners. They showed 115 separated peaks of PCB congeners. Total PCB concentrations were 879 and 769 ppm in 2 samples of Fukuoka rice oil and 57 and 83 ppm in 2 samples of Taiwan rice oil.

[Analysis of all PCB congeners in breast milk and blood of Yusho patients]

Breast milk and blood of Yusho patients were analyzed for polychlorinated biphenyl (PCB) congeners by High separation gas chromatography/Low resolution mass spectrometer. Seventy-one and forty-nine PCB congeners were identified and quantified in the breast milk and blood, respectively. Total PCB concentrations (Whole base) in breast milk of 2 Yusho patients were 69.9 and 15.1 ppb, respectively, being 11.6 and 2.5 times higher than those of 4 control breast milk. Average total PCB concentration of 5.0 ppb in whole blood of 13 Yusho patients was 3.6 times higher than those of control persons. Fourteen PCB congeners, such as 99, 117, 130, 137, 138, 156, 157, 164, 170, 171, 172, 189, 191 and 195, were particularly higher concentration in breast milk and blood of Yusho patients than in those of control persons. Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and coplanar PCBs were also analyzed in the breast milk of Yusho patients and control persons. Large portions, 83 and 74%, of Dioxin toxic equivalency (TEQ) in the 2 Yusho breast milk were consisted of TEQ of 2,3,4,7,8-pentaCDF only, while total TEQ in the breast milk of control persons was consisted of PCDFs 48%. PCDDs 29% and coplanar PCBs 23%.

Comparative study of 5' UTR and NS3R primers for the detection of GB virus C/hepatitis G virus RNA in Japanese

AIMS/BACKGROUND

Many epidemiological studies of new hepatitis viruses, including GB virus C (GBV-C) and hepatitis G virus (HGV), have used polymerase chain reaction (PCR) primers designed for the third nonstructural region (NS3R). However, a homology study of GBV-C and HGV genomes revealed that the 5' untranslated region (5'UTR) was more conserved than NS3R.

METHODS

We attempted to detect GBV-C/HGV using PCR primers corresponding to the 5' UTR, and compared its incidence to that derived from NS3R primers. Furthermore, PCR products amplified using the 5' UTR primers were sequenced and subjected to phylogenetic analysis.

RESULTS

In patients with chronic hepatitis C, the prevalence of GBV-C/HGV by PCR with the NS3R and 5' UTR primers was 5.1% (4/78) and 17.9% (14/78), respectively, and in patients on hemodialysis, it was 0% (0/81) and 5.9% (5/85), respectively. We could not detect GBV-C/HGV in patients with non-A-C liver disease. The incidence of GBV-C/HGV by 5' UTR primers was higher than by NS3R primers. After DNA sequencing at 5' UTR, phylogenetic analysis showed two types of GBV-C/HGV, Jap and HGV types.

CONCLUSION

5' UTR primers proved highly sensitive for detection of GBV-C/HGV and were superior to the NS3R primers.

[Squamous cell lung cancer with minimal-change nephrotic syndrome]

We report a case of squamous cell lung cancer with nephrotic syndrome. A 69-year-old man was admitted because of proteinuria and microhematuria. A plain chest X-ray film on admission showed a large mass in the left-lower lung field. The patient was given a diagnosis of minimal-change-nephrotic syndrome and squamous cell lung cancer. We first treated the nephrotic syndrome with glucocorticoid therapy, and then treated the lung cancer with chemo-radiotherapy. This reduced the lung cancer, alleviated the proteinuria, and completely resolved the nephrotic syndrome. Nephrotic syndrome is generally associated with malignant lymphoma and other nonepithelial neoplasms. As the underlying disease, epithelial neoplasms are less common, but lung cancer is one of the most widely reported. Histologically, most cases of cancer-associated nephrotic syndrome exhibit membranous nephropathy; Minimal-change nephrotic syndrome is rare. Deposits of immunocomplex on glomerular basement membrane are considered to play a pathogenic role in membranous nephropathy. However, the pathogenesis of minimal-change nephrotic syndrome is different.

Cytogenetic analysis of de novo acute myeloid leukemia with trilineage myelodysplasia in comparison with myelodysplastic syndrome evolving to acute myeloid leukemia

Characteristics of karyotypes were analyzed in de novo acute myeloid leukemia (AML) with trilineage myelodysplasia (AML/TMDS) at initial diagnosis and compared with myelodysplastic syndrome (MDS) cases that had evolved to AML (MDS/AML). Abnormal karyotypes were seen in 11 of 19 patients with AML/TMDS and 13 of 16 MDS/AML cases. Trisomy 8 was observed in 3 AML/TMDS cases as a sole anomaly and was also present in 3 MDS/AML cases but not as a sole finding. Although MDS/AML frequently displayed monosomies or long-arm deletions of chromosome 5, 7 and 9, only one case exhibited long-arm deletion (of chromosome 7) in AML/TMDS. Two or more chromosome aberrations were found in some cases in both groups. These findings suggest that AML/TMDS had passed through several preleukemic stages at diagnosis, as has been well documented in MDS and MDS/AML. Additionally, clonal evolution may have already occurred in AML/TMDS, as MDS transformed to AML is associated with clonal evolution.

Galactocerebroside and not glucocerebroside or ceramide stimulate epidermal beta-glucocerebrosidase activity

Glycosphingolipids including glucocerebroside (GluCer) and galactocerebroside (GalCer) have been recognized as bioreguratory lipids by our group and others. In addition, our recent study demonstrated that GalCer corrects dry skin conditions in humans. The processing of stratum corneum lipids, which occurs when beta-glucocerebrosidase (beta-GluCer'ase) changes GluCer to ceramide (Cer), is required to form the epidermal permeability barrier. We herein investigated the effects of GluCer, GalCer and Cer on the processing of GluCer to Cer by assaying epidermal beta-GluCer'ase in mice (155%, P < 0.01) when compared to vehicle treated controls, while neither GluCer nor Cer had this effect. Studies using inhibitors of beta-GluCer'ase or beta-galactosidase and measuring the optimum pH of the enzyme verified that GalCer specifically activated beta-GluCer'ase. We confirmed that GalCer significantly increased beta-GluCer'ase activity in the outer epidermal fraction (172%, P < 0.01) and that the activation of beta-GluCer'ase is not due to a direct activating effect of GalCer on the enzyme. Furthermore, the induction of beta-GluCer'ase activity by GalCer was also observed in cultured normal human deratinocytes (123%, P < 0.01). Finally, acylceramide content in stratum corneum was increased in mice treated with GalCer (194%, P < 0.0005). These results indicate that GalCer appears to affect the Cer construct in the stratum corneum by the activation of beta-GluCer'ase, which ultimately contribute to an enhancement of barrier formation.

Interstitial muscle insulin and glucose levels in normal and insulin-resistant Zucker rats

To study interstitial insulin and glucose concentrations, microdialysis was performed in the medial femoral muscles in normal SD rats as well as in insulin-resistant obese Zucker rats during a euglycemic insulin clamp. [14C]inulin was given (0.1 mCi/rat) as a constant subcutaneous infusion 24 h before the insulin clamp. Insulin infusion rates were 5-8 mU x kg(-1) x min(-1) (low rate) for 140 min and 10-20 mU x kg(-1) x min(-1) (high rate) for another 100 min. The relationship between insulin and [14C]inulin dialysate recoveries was evaluated in vivo and in vitro in plasma to calculate interstitial insulin concentration. Relative microdialysis recovery of interstitial insulin in vivo was 3.0 +/- 0.3% (mean +/- SE, n = 68). In normal SD rats, plasma and interstitial insulin concentrations were identical when plasma insulin was < or =250 mU/ml, whereas interstitial insulin was lower when plasma insulin was > or =350 mU/ml. Half-maximal glucose infusion rate was achieved in the presence of plasma and interstitial insulin concentrations of approximately 140 mU/ml, whereas maximal glucose disposal was seen at interstitial insulin concentrations of approximately 325 mU/ml, corresponding to approximately 500 mU/ml in plasma. In electrically stimulated and contracting (1 Hz) normal muscle with markedly increased blood flow, the dialysate insulin concentration was significantly higher at high rates, but not at low rates, of insulin infusion. In insulin-resistant obese Zucker rats, the interstitial insulin concentration was similar to that in plasma, even at pharmacological concentrations. The glucose infusion rate was significantly lower in the obese Zucker rats at both insulin infusion rates than in the lean animals. The glucose content in dialysates from skeletal muscle was equal in both obese and lean rats during the low insulin infusion rate. During the high insulin infusion rate, dialysate glucose concentrations decreased significantly in both groups but were significantly higher in the obese Zucker rats. The data suggest that transport of insulin and glucose diffusion across the capillary wall are rate limiting for insulin as well as for glucose metabolism in muscle in normal rats. This does not appear to be the case in the insulin-resistant obese Zucker rats, where the reduced insulin responsiveness in muscle is due to muscular cellular defects rather than an inhibited transcapillary delivery of insulin.

Propionyl coenzyme A carboxylase is required for development of Myxococcus xanthus

A dcm-1 mutant, obtained by transposon mutagenesis of Myxococcus xanthus, could aggregate and form mounds but was unable to sporulate under nutrient starvation. A sequence analysis of the site of insertion of the transposon showed that the insertion lies within the 3' end of a 1,572-bp open reading frame (ORF) designated the M. xanthus pccB ORF. The wild-type form of the M. xanthus pccB gene, obtained from a lambdaEMBL library of M. xanthus, shows extensive similarity to a beta subunit of propionyl coenzyme A (CoA) carboxylase, an alpha subunit of methylmalonyl-CoA decarboxylase, and a 12S subunit of transcarboxylase. In enzyme assays, extracts of the dcm-1 mutant were deficient in propionyl-CoA carboxylase activity. This enzyme catalyzes the ATP-dependent carboxylation of propionyl-CoA to yield methylmalonyl-CoA. The methylmalonyl-CoA rescued the dcm-1 mutant fruiting body and spore development. During development, the dcm-1 mutant cells also had reduced levels of long-chain fatty acids (C16 to C18) compared to wild-type cells.

Differences in the angiogenesis of benign and malignant ovarian tumors, demonstrated by analyses of color Doppler ultrasound, immunohistochemistry, and microvessel density

BACKGROUND

To clarify the differences in angiogenesis between benign and malignant ovarian tumors, the authors examined the immunohistochemical characteristics and the density of tumor vessels in both tumor groups. Intratumoral vascularization was observed preoperatively by transvaginal color Doppler ultrasound.

METHODS

The authors examined 106 patients with ovarian tumors preoperatively for the presence or absence of intratumoral blood flow and evaluated the blood flow waveforms of tumor vessels in patients showing intratumoral vascularization, using a resistance index (RI). The characteristics of both smooth muscle and endothelial cells in the vessels of each tumor were immunohistochemically assessed, using monoclonal antibodies against smooth muscle actin (SMA) and CD34 (an endothelial cell marker). The microvessel density (MVD) identified by CD34 was also evaluated in each tumor.

RESULTS

Intratumoral blood flow was found in 64 of 106 patients (60.4%). The tumors in 44 of these 64 patients were histopathologically benign, and the tumors in 20 were malignant. The malignant tumors showed a low RI (mean, 0.39 +/- 0.09) compared with benign tumors (mean, 0.62 +/- 0.12) (P < 0.001). The vessels of malignant tumors significantly demonstrated poor SMA expression and intense CD34 expression compared with the vessels of benign tumors. However, no significant differences were observed in MVD between the benign and malignant tumors.

CONCLUSIONS

In this study, immunohistochemical analysis demonstrated that low resistance to blood flow in vessels within malignant ovarian tumors may be associated with a poorly developed muscular coat in the tumor vessels, compared with that observed in benign tumors. The difference in the angiogenic natures of benign and malignant ovarian tumors showing intratumoral blood flow may thus be correlated with the endothelial cell activity of the tumor vessels and not the MVD.

[Insulin secretin and resistance accompany immobilization of the aged patient]

Physical activity is known to increase glucose tolerance and insulin sensitivity. To examine the influence of physical inactivity on insulin sensitivity in aged people, insulin sensitivity and secretion was measured by using a two-step euglycemic glucose clamp, a glucagon tolerance test (GTT), an oral glucose tolerance test (OGGT) and urinary CPR excretion in 11 aged patients immobilized in bed for more than 12 weeks. The results were compared with those of nine healthy mobile aged controls. The muscle volume of the immobilized patients decreased by 20-25% compared with that of the controls, and insulin sensitivity decreased 50% in each step. These results mean that the immobilized patients had decreased insulin sensitivity and responsiveness, even when there was muscle atrophy. The glucose and insulin responses in both the GTT and OGTT showed that there was a slight decrease in the initial response of insulin in the immobilized patients and was in the controls compared with adolescent controls. There was no difference in the initial response of insulin between the immobilized patients and the aged controls. The ratio of impaired glucose tolerance in the OGTT was 4/11 of the immobilized patients and 3/9 of the controls. Total insulin secretion was increased and insulin sensitivity and responsiveness was decreased in the immobilized patients. This suggests that the decreased insulin sensitivity was compensated for increased by insulin secretion in the immobilized patients.

Effect of beraprost sodium on the increased transendothelial permeation of albumin induced by high concentration of glucose

To determine whether a decrease in prostacyclin production is involved in the increase in endothelial permeability induced by a high concentration of glucose, we evaluated the effect of beraprost sodium, a stable prostacyclin analog, on the transendothelial permeation of albumin in cultured aortic cells. Permeation of albumin across an endothelial cell monolayer was significantly greater when the cells were cultured with a high concentration of glucose (400 or 800 mg/dl) than when they were cultured with 100 mg/dl glucose. No significant change in the permeation of albumin was observed when cells were cultured with 100 mg/dl glucose as compared with 100 mg/dl glucose plus 700 mg/dl mannitol. The addition of beraprost sodium to the culture medium completely restored the increase in the permeation of albumin brought about by 400 mg/dl glucose. These results suggest that increased transendothelial permeation of albumin by high glucose may be due in part to a decrease in prostacyclin production by the endothelial cells. Beraprost sodium may restore the endothelial barrier function affected by a high concentration of glucose.

Intrinsically aged epidermis displays diminished UVB-induced alterations in barrier function associated with decreased proliferation

Ultraviolet (UV) irradiation of the skin induces a variety of responses in the epidermis, including sunburn cell formation, epidermal hyperplasia, and a dose-dependent permeability barrier abnormality, an effect that appears to be dependent upon both UVB-induced hyperplasia and T-cell activation. Since intrinsically aged epidermis displays decreased epidermal turnover, diminished inflammatory response to various stimuli, including UVR, and impaired immune function, we investigated the effects of UVB on both epidermal barrier function and proliferation in hairless mice of increasing chronologic age (27, 61, and 90 wk). After a single UVB exposure (0.15 J/cm2 7.5 MED), a barrier abnormality developed (i.e., increased transepidermal water loss; TEWL), after a delay of > or = 48 h, regardless of age. In young mice (27 wk old), TEWL levels peaked at 72-96 h (9.9-fold over untreated controls), whereas increased epidermal [3H]thymidine incorporation preceded the peak TEWL increase (i.e., approximately 570% increase over controls at 48 h). In contrast, the UVB-induced increased in both TEWL and DNA synthesis were significantly diminished, with decreased epidermal hyperplasia evident, in intrinsically aged versus young mouse epidermis. Baseline epidermal thickness decreased with animal age (i.e., 16.8 +/- 3.1 vs. 27.9 +/- 0.7 microm for 90- vs. 27-wk-old animals, respectively; p < 0.02), suggesting that the diminished barrier response with aging reflects an attenuation of events subsequent to initial UVB exposure, rather than an increase in the UV dose delivered. These results demonstrate that (i) murine epidermis becomes less sensitive to UVB-induced barrier alterations with age and (ii) decreased DNA synthesis after UVB correlates with the age-related decrease in barrier dysfunction.

Changes in glycerophospholipid profile in experimental nephrotic syndrome

We investigated changes in the glycerophospholipids in kidney tissue and its various intracellular fractions in rats with nephrotic syndrome induced by puromycin aminonucleoside. The ethanolamine plasmalogen, 1-O-alk-1'-enyl-2-acyl-GPE (EP), was increased in kidney tissue obtained from the puromycin-treated animals. A similar increase was found in the mitochondria and endoplasmic reticulum (microsomes) of this tissue. These increases were not found in the liver. Since platelet-activating factor (PAF) is known to be produced in increased amounts in inflammatory disorders, it is suggested that the higher plasmalogen found in rat kidneys during experimental nephrotic syndrome might be derived from increased levels of this autacoid. The increase in PAF may also result in the elevation of plasma PAF-acetylhydrolase (AH) activity observed in these animals.

Age-related changes in branched-chain fatty acid concentration of the skin surface lipid from hairless mouse

Age-related changes in branched chain fatty acid (BCFA) concentration were studied with the skin surface lipid from hairless mice. A large proportion of BCFA was present in the cholesterol ester (CE) and wax diester (WDE) fraction of the skin surface lipid from hairless mice. The concentration of iso-series BCFA was highest at infancy and decreased with advancing age in both CE and WDE fraction. The concentration of anteiso-series BCFA appeared to be constant throughout the experiment.

Increased expression of a brain/embryo-type myosin heavy chain isoform (MIIB2) in mesangial proliferative glomerulonephritis

Proliferation of mesangial cells is frequently found in glomerulonephritis, such as IgA glomerulonephritis. Recent reports suggest that a brain/embryo-type myosin isoform (MIIB2) is involved in cell proliferation. We have studied the expression of MIIB2 in renal biopsy samples from patients with various renal diseases and in the renal tissues from the rat model of mesangial proliferative glomerulonephritis induced with anti-Thy 1.1 antibody. Immunohistochemical analysis of the biopsy samples using an anti-brain-type myosin heavy chain-specific monoclonal antibody (HBM1) indicated that 92% of the samples from patients with IgA glomerulonephritis contained a significant population of mesangial cells that reacted with the antibody. Most of the samples from patients with other types of proliferative glomerular diseases also contained HBM1-reactive mesangial cells, while none of the samples from patients with non-proliferative glomerular diseases contained a significant population of HBM1-reactive mesangial cells. The expression of a brain/embryo-type myosin heavy chain isoform (MIIB2) in the mesangial cells began at five days after injection of anti-Thy 1.1 antibody and peaked at the tenth day. On the other hand, the expression of the proliferating cell nuclear antigen in the mesangial cells was induced at two days after injection of anti-Thy 1.1 antibody and was maximal at the fourth day. These results indicate that the expression of the MIIB2 isoform by mesangial cells is accelerated in proliferative glomerulonephritis and suggest that the myosin isoform is involved in the phenotypic transformations of the glomerular tissues rather than in the cell proliferation.

Effect of a chemically-synthesized acylglucosylceramide, epidermoside, on normal human keratinocyte differentiation

Epidemosides (N-(0-linoleoyl)-(1)-hydroxy fatty acyl sphingosyl glucose) are found exclusively in the epidermis not in dermis, and are thought to play important role in forming the mammalian epidermal permeability barrier. A species of epidermoside isolated from guinea pig epidermis and named lipokeratinogenoside has been shown to enhance fetal rat keratinocyte differentiation. In the present investigation, we studied the effects of a chemically synthesized equivalent of human epidermoside on the viability and differentiation of cultured human keratinocytes (HK Cells). The chemically-synthesized epidermoside was not toxic to cultured HK Cells at concentrations of 0.01 to 10 micrograms/ml. When 10 micrograms/ml of the chemically-synthesized epidermoside was added to keratinocyte growth medium containing 1.2 mM Ca2+, HK Cells showed a 5.6-fold increase of keratin content compared to the vehicle treated control at 144 h of cultivation, and they also displayed morphological changes suggestive of differentiation. A similar increase of cellular keratin content was observed in HK cells treated with tetradecanoyl phorbol-13 myristyl-12 acetate (TPA), an agent known to enhance the differentiation of keratinocytes. Lipokeratinogenoside also increased the keratin content of cultured HK cells. These results suggest that epidermosides have an ability to enhance keratinocyte differentiation. Epidermoside could thus be a key molecule, not only as a constituent of the epidermal permeability barrier, but also as a regulator of keratinocyte differentiation.

Effects of glucose and an aldose reductase inhibitor on albumin permeation through a layer of cultured bovine vascular endothelial cells

The effects of high glucose concentrations on the selective permeability of a layer of cultured bovine vascular endothelial cells (ECs) were investigated. ECs were derived from the intima of the thoracic aorta and permeability to nonglycated albumin, glycated albumin, and fluorescein dextrans (FDs) of molecular mass to albumin was measured. ECs were cultured on a filter coated with type I collagen and preincubated in the presence of various glucose concentrations for 96 h. Human serum albumin was glycated by incubation with glucose in vitro. Nonglycated and glycated albumin were separated by affinity column chromatography. The permeation rates of nonglycated and glycated albumin as well as those of neutral and anionic FD through the EC layer were increased by preincubation of cells with high glucose concentrations (22.2 and 44.4 mmol/l). The permeation rate of glycated albumin was significantly less than that of nonglycated albumin at all glucose concentrations tested, whereas the permeation rate of anionic FD was significantly lower than that of neutral FD only at a physiological glucose concentration (5.6 mmol/l). The aldose reductase inhibitor ponalrestat partially inhibited the high glucose-induced increase in trans-endothelial permeation of albumin (both nonglycated and glycated), but had no effect on the increased permeation of FD. These results indicate that high glucose concentrations enhance trans-endothelial permeability to albumin and FD and may disturb the barrier function of vascular ECs. Furthermore, metabolism of glucose via the polyol pathway may contribute to abnormalities in trans-endothelial permeability.

Side-chain structure is critical for the transport of sterols from lysosomes to cytoplasm

Macrophages take up and metabolize negatively charged liposomes containing free cholesterol efficiently, resulting in a massive accumulation of cholesteryl esters and triacylglycerols in their cytoplasm (Nishikawa, K., Arai, H. and Inoue, K. (1990) J. Biol. Chem. 265, 5226-5231). This system was used to assess the effects of structural variation of sterol on the intracellular transport and the metabolism of endocytosed sterols by the cells. Liposomes containing phytosterols with an extra one (campesterol) or two (beta-sitosterol, stigmasterol, fucosterol) carbons at the C-24 position of the cholesterol side-chain were endocytosed as efficiently as those containing cholesterol without exhibiting any apparent toxicity on the cells. Esterification of endocyotosed phytosterols was, however, extremely low; campesterol esterification was only 20% that of cholesterol and either beta-sitosterol or stigmasterol was not esterified appreciably. A morphological study showed that the endocytosed phytosterols were accumulated in the phagolysosomes of the cells. Blocking of esterification of endocytosed cholesterol by an acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor did not lead to cholesterol accumulation in the phagolysosomes. These data suggest that accumulation of endocytosed phytosterols in phagolysosomes is not a consequence of the inability of the cell to esterify sterols in the endoplasmic reticulum. In the light of these observations, we conclude that cultured macrophages can discriminate between sterols that differ only by a methyl or ethyl group at the C-24 position at their lysosomal compartment.

Increased transendothelial permeation of albumin by high glucose concentration

Vascular endothelial cells, which are polyfunctional, play an important role in the pathogenesis of diabetic complications. The increase in vascular permeability, ie, regulated by vascular endothelial cells, has been reported in patients with diabetes mellitus complicated by angiopathy. To determine the role of hyperglycemia in endothelial cell permeability, we examined the effect of high concentrations of glucose on the permeability of cultured bovine aortic endothelial cells. The permeations of albumin and fluorescein-labeled dextran (FD) across endothelial cell monolayers were increased when cultured with a high concentration of glucose (400 mg/dL). This increased permeation of albumin but not FD was temperature-dependent and was partially reduced by adding 100 mumol/L ponalrestat (ICI 128,436, Statil; ICI, Cheshire, UK), which is an aldose reductase inhibitor. Stimulation or inhibition of Na,K-adenosine triphosphatase (ATPase) in bovine aortic endothelial cells failed to alter their permeability. These findings suggest that high concentrations of glucose enhance transendothelial permeability of albumin in part by activating the polyol pathway, but independently of Na,K-ATPase activity.

Septic shock due to Pseudomonas aeruginosa in a previously healthy woman

Pseudomonas aeruginosa septicemia rarely occurs in non-immunocompromised adults. We present a case of septic shock following Pseudomonas aeruginosa pneumonia in a previously healthy 48-year-old woman. The onset was sudden, with back pain, pyrexia and shock. Chest radiographs revealed pneumonia, and Pseudomonas aeruginosa was identified from blood and sputum cultures. Therapy with dopamine, piperacillin and fluid replacement led to a prompt recovery. Laboratory tests failed to reveal any immunological deficits. Including this case, only five cases of Pseudomonas aeruginosa septicemia in patients though to be non-immunocompromised have been reported. Two remarkable features of this type of Pseudomonas infection are apparent: i) it commonly develops from pneumonia and ii) it has a better prognosis than that in immunocompromised hosts.

1-O-alkyl-2,3-diacylglycerols in the skin surface lipids of the hairless mouse

A neutral lipid class was isolated by thin-layer chromatography from the skin surface lipids of the hairless mouse. The fraction migrated faster than triglycerides and had a migration rate similar to that of diacyl alkanediols (diester wax). Upon deacylation, however, the long-chain diols were identified as 1-alkylglycerol ethers based on their chromatographic properties and on the mass spectra of their nicotinylidene derivatives. Thus, the skin lipid fraction was identified as 1-O-alkyl-diacylglycerol. The alkyl moieties were all saturated and even-numbered and ranged in chainlength from C16 to C22 with 1-O-hexadecylglycerol amounting to 34% of the total glycerol ether moieties. The fatty acids derived from this lipid fraction were mostly monoenoic with chainlengths ranging from C16 to C24. The major acyl component was eicosenoic acid (20:1) representing 61% of the total fatty acids.

Impaired feedback inhibition of insulin secretion by hyperinsulinemia in patients with insulinoma

By means of the euglycemic three step hyperinsulinemic clamp technique, suppression of endogenous C-peptide secretion by exogenous insulin infusion was evaluated in patients with insulinoma (n = 8) and healthy controls (n = 20). Euglycemic hyperinsulinemic clamp studies were performed with an artificial pancreas (STG-22 NIKKISO, Tokyo, Japan). Insulin (Actrapid human insulin) was infused at the rate of 1.12, 3, and 10 mU/kg/min. Plasma glucose levels were clamped at 80 mg/dl, and high insulin levels were maintained in all subjects (833 +/- 78 microU/ml at the rate of 10 mU/kg/min insulin infusion). During the clamp studies, plasma C-peptide levels in normal subjects declined from 2.0 +/- 0.2 to 0.9 +/- 0.2 ng/ml, indicating suppression of endogenous insulin secretion by exogenous insulin infusion. In patients with insulinoma, plasma C-peptide levels were 3.1 +/- 1.6 ng/ml in the basal state, and were not suppressed even during exogenous hyperinsulinemia. We concluded that the feedback inhibition of insulin secretion by exogenous insulin infusion is attenuated in patients with insulinoma, and that the hyperinsulinemic clamp technique may be a useful method for the diagnosis of insulinoma.

Chinese hamster ovary cells expressing a novel type of acetylated low density lipoprotein receptor. Isolation and characterization

Macrophage scavenger receptors mediate the recognition of a wide range of negatively charged macromolecules including acetylated low density lipoproteins (AcLDL). Chinese hamster ovary (CHO) cells were cultured in the presence of increasing concentrations of simvastatin, a cholesterol biosynthesis inhibitor, and AcLDL as the sole source of exogenous lipoproteins. The cells surviving under these conditions specifically bound 125I-labeled AcLDL with high affinity and degraded them via an endocytic pathway. Unexpectedly, the association and degradation of 125I-labeled AcLDL by these CHO cells were not inhibited by dextran sulfate, fucoidan, and polyinosinic acid, competitors of macrophage scavenger receptors, but were completely inhibited by maleylated bovine serum albumin. Furthermore, these cells effectively took up negatively charged liposomes containing acidic phospholipids such as phosphatidylserine and phosphatidic acid, whereas CHO cells expressing macrophage scavenger receptors did not. AcLDL and negatively charged liposomes were cross-competed with each other. Northern blot analysis using the cDNA for the macrophage scavenger receptor revealed that these CHO cells did not express this receptor. From these observations, we conclude that the isolated CHO cells express a novel type of AcLDL receptor, which is distinct from macrophage scavenger receptors with respect to ligand specificity and competitor sensitivity.

Effect of alpha-tocopherol on in vitro and in vivo metabolism of low-density lipoproteins in haemodialysis patients

It has been reported that some modified low-density lipoproteins (LDLs) such as glycated LDL and malondialdehyde-rich LDL (MDA-LDL) probably exist in the circulation. The present study was undertaken to investigate the in vitro and in vivo metabolism of MDA-LDL occurring in chronic haemodialysis patients and the effects of alpha-tocopherol on these abnormalities. MDA-LDL from haemodialysis patients was degraded more rapidly by human monocyte-derived macrophages and disappeared more slowly from the circulation when compared with LDL from healthy controls. Treatment with alpha-tocopherol at doses of 600 mg/day for 2 weeks resulted in improvement of these metabolic abnormalities depending upon the degree of return to normal MDA concentrations in LDL.

Randomized, controlled trial of trivalent oral poliovirus vaccine (Sabin) starting at birth in Ghana

To evaluate the efficacy of the schedule currently recommended for immunization with trivalent oral poliovirus vaccine (TOPV) (i.e., at birth, 6 weeks, 10 weeks, and 14 weeks after birth), we randomly assigned 452 infants into test (231 infants) and control (221 infants) groups. The test group received TOPV as currently recommended, and the dose at birth was omitted for the control group. At 10, 14, and 18 weeks of age, the levels of poliovirus neutralizing antibodies as well as seroconversion rates were consistently higher for the test group than for the control group. The final seroconversion rates against poliovirus types 1, 2, and 3 were 83.5%, 91% and 83%, respectively, for the test group and 75%, 83.2%, and 79.1%, respectively, for the control group. The TOPV immunization schedule starting at birth therefore produced better results. Seroconversion rates as well as antibody levels were highest in infants with low maternal antibodies.

[A case of syndrome X whose hyperglycemia, hyperlipidemia and hypertension were improved as accompanying with decreased insulin resistance]

A 60-year-old man was admitted to the Kyushu University Hospital because of poor glycemic control of diabetes mellitus. Although he had been treated with glicrazide and nifedipine for his diabetes and hypertension, the controls of the diseases were unsatisfactory. Plasma triglyceride level was 186 mg/dl. Furthermore, extreme insulin resistance was found by measuring glucose infusion rate with an euglycemic hyperinsulinemic clamp method. These findings were compatible to those seen in syndrome X. After admission, diet therapy of 1,800 Cal was started and his metabolic disorders such as hyperglycemia, hyperlipidemia, and hypertension were all improved. Moreover, euglycemic hyperinsulinemic clamp study also revealed a decreased insulin resistance after diet therapy. Our experience from the case suggested that insulin resistance may closely related with the metabolic disorders of the disease "syndrome X".

[A case of idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia associated with chronic nephritis]

A 48-year-old female who had general fatigue was admitted to our hospital. She had swelling of the axillary, inguinal, and paraaortic lymph nodes and mediastinal lesions. Laboratory examinations showed anemia, polyclonal hyperimmunoglobulinemia with IgG 5570 mg/dl, renal dysfunction and interstitial changes of the lungs. Microscopic findings of hematoxylin-eosin staining in biopsy specimens of the left inguinal and axillary lymph nodes revealed increased levels of infiltration of mature plasma cells without evidence of malignancy. Immunoperoxidase staining showed intracytoplasmic polyclonal immunoglobulin. These findings were identical to those of idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia (IPL) described by Mori et al. (1980). The specimens also showed evidence of chronic nephritis with infiltration of lymph cells and a slight invasion of plasma cells. Accordingly this case was diagnosed as IPL with renal involvement, which is associated with chronic nephritis. Recently, five cases of IPL with renal dysfunction have been reported. In particular, two cases of IPL with renal dysfunction, which included our case, revealed an increased level of IL6. These findings suggest that the occurrence of renal involvement with IPL may be related to changes in IL6, which is an important factor in the pathogenesis of IPL.

Effects of a new oral hypoglycaemic agent (CS-045) on metabolic abnormalities and insulin resistance in type 2 diabetes

The effects of a thiazolidinedione antidiabetic agent (CS-045) on diabetic metabolic abnormalities were studied in a double-blind clinical trial. Fourteen patients with Type 2 diabetes were selected according to study criteria. Eight were treated with oral CS-045 at 400 mg daily, and six were given placebo. A multi-step, hyperinsulinaemic, euglycaemic clamp study, with simultaneous plasma free fatty acid study, and glucagon tolerance test were performed before and after administration of drug. Following 3 months of treatment with CS-045, there were significant decreases in the mean levels of fasting plasma glucose (from 9.18 +/- 0.95 to 7.78 +/- 0.44 mmol l-1), postprandial plasma glucose (from 11.8 +/- 1.23 to 10.36 +/- 1.06 mmol l-1), and haemoglobin A1c (from 9.3 +/- 0.4 to 6.8 +/- 0.4%). Insulin sensitivity also improved (1st step: from 3.12 +/- 0.33 to 4.70 +/- 0.47 mg kg-1 min-1 (p < 0.01); 2nd step: from 5.61 +/- 0.63 to 7.54 +/- 0.58 mg kg-1 min-1 (p < 0.01); 3rd step: from 9.21 +/- 0.67 to 11.10 +/- 0.87 mg kg-1 min-1). The fasting free fatty acid level decreased significantly from 0.28 +/- 0.04 to 0.22 +/- 0.02 g l-1. The residual free fatty acid level (%) under insulin infusion clamp conditions decreased significantly from 63.7 +/- 9.7 to 45.0 +/- 9.2%. CS-045 treatment was associated with decrease in total cholesterol, total triglycerides, and increase in HDL cholesterol. Basal C-peptide immunoreactivity level decreased, but there was no change in the peak C-peptide immunoreactivity value.(ABSTRACT TRUNCATED AT 250 WORDS)

Mantle hydrocarbons: abiotic or biotic?

Analyses of 227 rocks from fifty localities throughout the world showed that mantle derived rocks such as tectonized peridotites in ophiolite sequences (tectonites) arid peridotite xenoliths in alkali basalts contain heavier hydrocarbons (n-alkanes), whereas igneous rocks produced by magmas such as gabbro arid granite lack them. The occurrence of hydrocarbons indicates that they were not derived either from laboratory contamination or from held contamination; these compounds found in the mantle-derived rocks are called here "mantle hydrocarbons." The existence of hydrocarbons correlates with petrogenesis. For example, peridotite cumulates produced by magmatic differentiation lack hydrocarbons whereas peridotite xenoliths derived from the mantle contain them. Gas chromatographic-mass spectrometric records of the mantle hydrocarbons resemble those of aliphatics in meteorites and in petroleum. Features of the hydrocarbons are that (a) the mantle hydrocarbons reside mainly along grain boundaries and in fluid inclusions of minerals; (b) heavier isoprenoids such as pristane and phytane are present; and (c) delta 13C of the mantle hydrocarbons is uniform (about -27%). Possible origins for the mantle hydrocarbons are as follows. (1) They were in organically synthesized by Fischer-Tropsch type reaction in the mantle. (2) They were delivered by meteorites and comets to the early Earth. (3) They were recycled by subduction. The mantle hydrocarbons in the cases of (1) and (2) are abiogenic and those in (3) are mainly biogenic. It appears that hydrocarbons may survive high pressures and temperatures in the mantle, but they are decomposed into lighter hydrocarbon gases such as CH4 at lower pressures when magmas intrude into the crust; consequently, peridotite cumulates do not contain heavier hydrocarbons but possess hydrocarbon gases up to C4H10.

Prevention of ongoing lipid peroxidation by wound excision and superoxide dismutase treatment in the burned rat

To determine if wound excision and superoxide dismutase (SOD) treatment prevent ongoing lipid peroxidation after burn injury, the plasma, kidney, and lung lipid peroxide (LPO) levels in 25% total body surface area (TBSA) burned rats was studied. The animals were given intraperitoneal bovine copper-, zinc-SOD (Cu/Zn-SOD) (50,000 U/kg dissolved in saline) or saline immediately after burns and were operated by wound debridement and allograft 2 hours after the burn. We measured LPO levels of 6-hour postburn plasma and tissues by the thiobarbituric acid (TBA) method, and measured the manganese SOD (Mn-SOD) by an enzyme-linked immunosorbent assay. Wound excision alone prevented the increase of plasma LPO levels but could not prevent the increase in tissues. The combination of wound excision and Cu/Zn-SOD treatment markedly inhibited the increase in both plasma and tissue LPO levels after the burn, but did not prevent the increase in Mn-SOD. Wound excision in conjunction with SOD-treatment might be therapeutic in the management of severe burns.

[Isolated gonadotropin deficiency and secretory discrepancy of cortisol and adrenal androgen by hemochromatosis secondary to congenital dyserythropoietic anemia]

A 37-yr-old woman was admitted to our hospital for evaluation of diabetes mellitus, liver cirrhosis and primary amenorrhea. Serological and hematological examinations revealed that she suffered from hemochromatosis secondary to congenital dyserythropoietic anemia (CDA), characterized by ineffective hematopoiesis and erythropoietic dysplasia. Iron deposition was suggested by MRI on the pancreas, liver and pituitary gland. Endocrinological examinations demonstrated that she had isolated gonadotropin deficiency and ovarian failure, resulting in hypogonadotropic hypogonadism. In addition, despite normal responses of serum cortisol and plasma aldosterone to ACTH and furosemide-standing tests, respectively, serum dehydroepiandrosterone (DHEA) responded poorly to ACTH test, suggesting selective damage of zona reticularis in adrenocortical steroidogenesis in association with hemochromatosis.

[Effects of long-term endurance training on left ventricular dimensions and function in female distance runners]

Ultrasoundcardiogram (UCG) was measured to evaluate the effects of 2 years of endurance training on left ventricular dimensions and function in 3 female collegiate runners (mean age 19.7 years). All subjects had had an experience in endurance training as athletes and underwent the endurance training at the college for two years. Training consisted mainly of about 2 hours of running, 3 to 4 days a week. Training effects were found as measured by a 5000m-run pretraining (mean 19: 40.3 min) and post-training (mean 18: 49.3 min). The average increase in maximal oxygen uptake (VO2max/kg) after training was 9.4% (P < 0.05). UCG's dimensional variables such as LVDd, LVPWT and IVST in the post-training period did not reveal any increase. However, LVDs as a cardiac dimension showed a tendency to decrease, and functional variables such as SV, EF, FS showed a tendency to increase. This functional improvement appeared to be due to a decrease in LVDs. From these results, it is likely that the endurance training prior to this study might have helped an effective adaptation in their cardiac dimensions. Thus, we suggest that prior to this study cardiac dimensions had extended and enlarged to a certain extent, and then cardiac function might be improved as the subsequent physiological phenomenon.

Effective inhibition of hydroxyl radicals by hydroxylated biphenyl compounds

In aqueous media, approximate rate constants for the reactions between hydroxyl radicals (.OH) and biphenyl compounds such as dehydrodieugenol, magnolol, honokiol, dehydrodidihydroeugenol, dehydrodivanillyl alcohol, and dehydrodicreosol were estimated by competition reactions for .OH between these biphenyls and 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). By measuring the decrease in the height of the EPR signals of the .OH spin adduct, rate constants in the order of 10(9) to 10(10) M were measured.

[Relationship between aging and hydroxyproline content of serum in human being]

The authors have studied the effects of physical exercise on extracellular substances of several tissues in animals. Hydroxyproline (Hyp) exist in the form of peptide and the free state in blood. It is generally thought that Hyp in blood derived from the decomposition of collagen in tissue. To clarify the influence on collagen metabolism due to aging and exercise training, we attempted to see the changes of Hyp content of serum before and after exercise in human being. Subjects were 51 adult aged 20 to 74 years, and 10 nonathletes and 51 athletes, aged 18 to 22 years. The Hyp content in serum was measured by woessner's method. The Hyp content of serum decreased with age. This fact suggests that the formation of intramolecular and intermolecular cross-links in collagen of tissue is accelerated by aging. And there is a possibility that the proportion of insoluble collagen increased in tissue of aged human being. Before the exercise, Hyp content of serum in athlete was lower than that in nonathletes. Hyp content of serum increased remarkably after the exercise in athlete. These results suggest that the collagen metabolism may be accelerated by continuous exercise training.

Superoxide dismutase with prolonged in vivo half-life inhibits intravascular hemolysis and renal injury in burned rats

Although superoxide radicals and related metabolites have been postulated to underlie the pathogenesis of burn injury, critical evidence supporting this hypothesis is lacking. To test whether superoxide radicals play critical roles in burn injury, the effect of a superoxide dismutase (SOD) derivative (SM-SOD) was tested on intravascular hemolysis and renal tubular injury in rats subjected to burn shock. Within 3 hours after a given full-thickness burn of approximately 24% of body surface area, plasma levels of lipid peroxides increased significantly with concomitant increase in intravascular hemolysis. Histological examination showed a marked deposition of hemoglobin-like casts in renal tubules of the burned rats. Intravenous administration of SM-SOD (10 mg/kg) 30 minutes before the burn injury significantly inhibited the increase of plasma lipid peroxides and the occurrence of intravascular hemolysis. SM-SOD also inhibited the deposition of casts in renal tubules. These results indicate that superoxide radicals play critical roles in the pathogenesis of intravascular hemolysis and renal damage induced by burn injury.

Recovery of muscle power after high-intensity short-term exercise: comparing boys and men

This study was conducted to determine whether boys differ from men in their ability to recover from high-intensity exercise. Two groups of volunteers, 8 prepubertal boys (9-12 yr) and 8 young men (19-23 yr), were similar in their peak oxygen uptake (49.6 +/- 6.6 vs. 51.1 +/- 6.6 ml.min-1 x kg-1), adiposity, and activity levels. On three different occasions subjects performed two consecutive 30-s all-out cycling tasks [Wingate anaerobic test (WAnT)], separated by a 1-, 2-, or 10-min recovery interval. In the boys, mean power reached 89.9 +/- 3.6% of the initial value after 1 min of recovery, 96.4 +/- 2.3% after 2 min, and 103.5 +/- 1.3% after 10 min. For the men, the values were 71.2 +/- 2.6, 77.1 +/- 2.4, and 94.0 +/- 1.3%, respectively (boys vs. men, P < 0.0001). Relative to the external work performed during the first WAnT, the boys had a higher net oxygen uptake (exercise--resting) during the test than the men (83.8 +/- 18.4 vs. 57.8 +/- 6.1 ml/kJ). After the WAnT, the net CO2 output and the respiratory exchange ratio were lower in the boys, and they recovered faster. It was concluded that boys recover faster than men from high-intensity short-term exercise. This may reflect a lower reliance on glycolysis during the WAnT in the boys, leading to less acidosis. It is also possible that the boys had a faster postexercise removal of metabolites.