Phospholipase A2 is necessary for tumor necrosis factor alpha-induced ceramide generation in L929 cells

The role of cytosolic phospholipase A2 (cPLA2) in the regulation of ceramide formation was examined in a cell line (L929) responsive to the cytotoxic action of tumor necrosis factor alpha (TNFalpha). In L929 cells, the addition of TNFalpha resulted in the release of arachidonate, which was followed by a prolonged accumulation of ceramide occurring over 5-12 h and reaching 250% over base line. The formation of ceramide was accompanied by the hydrolysis of sphingomyelin and the activation of three distinct sphingomyelinases (neutral Mg2+-dependent, neutral Mg2+-independent, and acidic enzymes). The variant cell line C12, which lacks cPLA2, is resistant to the cytotoxic action of TNFalpha. TNFalpha was able to activate nuclear factor kappaB in both the wild-type L929 cells and the C12 cells. However, TNFalpha was unable to cause the release of arachidonate or the accumulation of ceramide in C12 cells. C6-ceramide overcame the resistance to TNFalpha and caused cell death in C12 cells to a level similar to that in L929 cells. The introduction of the cPLA2 gene into C12 cells resulted in partial restoration of TNFalpha-induced arachidonate release, ceramide accumulation, and cytotoxicity. This study suggests that cPLA2 is a necessary component in the pathways leading to ceramide accumulation and cell death.

B7-1-transfected tumor vaccine counteracts chemotherapy-induced immunosuppression and prolongs the survival of rats bearing highly metastatic osteosarcoma cells

To investigate the therapeutic efficacy of B7-1-expressing tumor vaccine on metastatic osteosarcoma, we introduced mouse B7-1 cDNA into a rat osteosarcoma cell line, MSK-8G. Flow cytometric analysis confirmed that the transfectants designated as B7-1-8G 10-1 and B7-1-8G 15-5 stably expressed B7-1 molecules on the cell surface. B7-1 transfectants were not only rejected by immunocompetent F344 rats but also conferred systemic immunity that protected against challenge with B7-negative parental osteosarcoma cells. In contrast, T-cell-deficient nude rats failed to reject B7-1 transfectants, indicating that T cells play a major role in the development of systemic immunity. We then conducted experimental therapies using irradiated B7-1-transfected tumor vaccine and methotrexate in an orthotopic implantation model. B7-1-transfected tumor vaccine significantly reduced the number of pulmonary metastatic nodules. Moreover, the combination of methotrexate and tumor vaccine further decreased the number of pulmonary metastatic nodules. Most important, the combined therapy with methotrexate and tumor vaccine resulted in a tumor-free condition as judged by the histopathological absence of tumors and survival of rats for more than 180 days. Furthermore, B7-1-transfected tumor vaccine could counteract the immunosuppressive effect of methotrexate. These findings strongly suggest that the B7-1-transfected tumor vaccine may be of clinical value for patients with metastatic osteosarcoma who exhibit immunosuppression due to chemotherapy.

Fragile mitochondrial DNA: the missing link in the apoptotic neuronal cell death in Parkinson's disease

The oxidative stress theory, the mitochondrial (mt) hypothesis, and the apoptosis hypothesis are proposed as the cause of neuronal cell death in Parkinson's disease (PD). However, the direct link between them has remained unknown. Recently, the mt control of nuclear apoptosis is documented that collapse of mt transmembrane potential due to energy crisis leads to release of apoptotic protease activating-factors into cytosol and subsequently nuclear DNA fragmentation. However, an endogenous factor responsible for the energy crisis under physiological conditions is missing. Here we report the missing factor as that mtDNA in the striatum of a parkinsonian patient fragments into 134 types of deleted pieces, being detected by the total detection system for mtDNA deletion. The system has documented that the mtDNA is extremely susceptible to hydroxyl radical damage, hence to oxidative stress, enough to cause the cellular energy crisis. The extensive fragility of mtDNA in brain stem could link the oxidative stress up with the apoptotic neuronal cell-death of PD.

[Prognosis of renal cell carcinoma coexisting with renal cystic diseases--results of nation-wide survey in Japan]

OBJECTIVE

To study the outcome of the patients with renal cell carcinoma (RCC) coexisting with renal cystic disease.

SUBJECTS AND METHODS

The nation-wide survey conducted in 1989 enrolled 223 patients with RCC coexisting with renal cystic disease. Of those 223, we could follow up 216 patients in the second survey in 1994.

RESULTS

Renal cystic diseases coexisting with RCC included simple renal cysts in 69 cases, acquired cystic disease of the kidney (ACDK) in 61, cystic RCC in 54, multilocular renal cysts in 19, polycystic kidney in 3, miscellaneous cysts in 9, and unspecified cyst in 1. The overall 5-year survival was 84%. The mean survival of the patients without any symptoms was significantly higher than that of those with symptoms. The survival of those with ACDK was lowest, and that will cystic RCC was highest. The survival was significantly different between the two groups, however the disease specific survival excluding the effect of dialysis was not significantly different between the two groups. Regarding TNM category, those with pT1 or pT2, comprising 87% of the subjects, carried a prognosis more favorable than those with pT3 or pT4. Among those undergoing cyst puncture (47 patients), positive cytology resulted in poorer prognosis. However, there was no such difference in the prognosis between punctured group and non-punctured group.

CONCLUSION

Those with RCC coexisting with renal cystic disease carried a favorable prognosis. Cyst puncture were not concluded to exert an unfavorable effect on the prognosis at least in this study.

Inhibition of a Porphyromonas gingivalis colonizing factor between Actinomyces viscosus ATCC 19246 by monoclonal antibodies against recombinant 40-kDa outer-membrane protein

1. Porphyromonas gingivalis, an important pathogen in human periodontal disease, aggregates with Actinomyces viscosus ATCC 19246. 2. Monoclonal antibodies (mAbs) against purified recombinant 40-kDa outer-membrane protein (r40-kDa, OMP) of P. gingivalis 381 inhibited its coaggregation with A. viscosus ATCC 19246 in a dose-dependent manner. 3. Five mAb clones against r40-kDa OMP were selected. The isotype of the five was IgG1. 4. Pg-ompA2 inhibited the coaggregation of several strains of P. gingivalis with A. viscosus ATCC 19246 cells.

Budd-Chiari syndrome resulting from intrahepatic IVC compression secondary to blunt hepatic trauma

Hepatic venous outflow obstruction (Budd-Chiari syndrome)is a rare sequel of abdominal trauma. Three cases of Budd-Chiari syndrome resulting from obstruction to the intrahepatic IVC by liver injury are reported. The CT findings include extrinsic compression of the intrahepatic inferior vena cava (IVC) by intraparenchymal and/or subcapsular hepatic haematoma, non-visualization or narrowing of one or more main hepatic veins with intravenous contrast-enhanced CT, and accumulation of low attenuation ascites. This entity should be distinguished from intraperitoneal bile leak or hemoperitoneum associated with major liver injury with which it could be confused. Decompression of the IVC and hepatic veins by surgical or percutaneous drainage of intrahepatic or subcapsular hematoma was curative in two of the three patients.

Genes of human ATP synthase: their roles in physiology and aging

The reaction of ATP synthase (F0F1) is the final step in oxidative phosphorylation (OXPHOS). Although OXPHOS has been studied extensively in bacteria, no tissue-specific functions nor bioenergetic disease, such as mitochondrial encephalomyopathy and aging occur in these organisms. Recent developments of the Human Genome Project will become an important factor in the study of mammalian bioenergetics. To elucidate the physiological roles of human F0F1, genes encoding the subunits of F0F1 were sequenced, and their expression in human cells was analyzed. The following results were obtained: A. The roles of the residues in F0F1 are not only to transform the energy of the electrochemical potential (delta mu H+) across the membrane, but also to respond rapidly to the changes in the energy demand by regulating the intramolecular rotation of F0F1 with the delta mu H+ and the inhibitors of the ATPase. B. The roles of the control regions of the F0F1 genes, are to coordinate both mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) depending on the energy demand of the cells, especially in muscle, C. The cause of the age-dependent decline of ATP synthesis has been attributed to the accumulation of mutations in mtDNA. However, the involvement of nDNA in the decline is also important because of telomere shortening in somatic cells, and age-dependent mtDNA expression analyzed with rho degree cells (cells without mtDNA).

Pitfalls in aneurysm surgery in acute stages

Since the dawn of aneurysm surgery, many aneurysms present a more complex challenge. Large size, intimacy with critical perforator branches, deep location, atherosclerotic walls, ruptured aneurysms in the elderly and incorporation of afferent or efferent arteries in the dome represent factors that singly or in combination preclude safe clipping while high pressure circulation continues in the aneurysm. Despite the relative frequency of many class of aneurysms, there remains in the neurosurgical community some degree of confusion regarding the detailed anatomic features and the technical aspects of the treatment of these lesions in the acute stage. In our study of 1,433 cases, we have enumerated four aspects of the pitfalls in aneurysm surgery which should be considered when planning the operative approach to these lesions. These four aspects will be reviewed in relation to the aneurysm surgery: (1) inadequate pre-operative planning; (2) inappropriate response to unexpected premature rupture; (3) poor clipping techniques and clip selection; (4) unintentional occlusion or injury of perforating branches. This discussion will simply elaborate our own conceptual and microsurgical technical approach in dissecting the aneurysms. Minimal retraction was used during the whole surgical procedure. The intracranial brain tension was reduced through a ventricular tap for hydrocephalus or evacuation of hematoma prior to aneurysm surgery. A venous pathway was established for blood circulation. Sharp dissection, using our newly designed jet irrigation bipolar suction method was employed. Regarding the clipping of the aneurysm, we used the tentative clipping and the dome coagulation method thereby preventing the ischemic changes and shortening of the entire clipping procedure. Although the strategies, discussed represent simply our approach to this problem, the principles included have proven quite successful and have allowed safe and definitive treatment in the overwhelming majority of patients and also options to overcome the pitfalls in aneurysm surgery.

Multicenter genetic study of retinitis pigmentosa in Japan: I. Genetic heterogeneity in typical retinitis pigmentosa

A nationwide, multicenter study of typical retinitis pigmentosa (RP) was carried out in collaboration with 18 hospitals throughout Japan to obtain current information for genetic counseling. We analyzed the genetic heterogeneity of RP based on the parental consanguinity of 434 probands registered during a 6-month period in 1990. A gradual decline in the frequency of consanguineous marriage was recognized among the normal parents of RP patients. The relative frequencies of inheritance patterns were estimated as: autosomal recessive, 25.2%; autosomal dominant, 16.9%; X-linked, 1.6%; and simplex, 56.3%. A comparison of these results with previous reports in Japan revealed a decline in the relative frequency of autosomal recessive cases and an increase in simplex cases. This suggests a decrease in the incidence of autosomal recessive retinitis pigmentosa in Japan, as well as the necessity for exhaustive investigations aimed at identifying inheritance patterns for RP patients seeking genetic counseling.

[Diagnostic imaging of renal pedicle injury]

We reviewed the radiological findings of 8 patients with renal pedicle injury admitted to our emergency center from January 1986 through September 1995 and compared them with the previously reported findings. The patients included 3 with renal artery occlusion and 5 with avulsion or disruption of renal pedicle vasculature. Extended retroperitoneal hematoma such as contralateral pararenal or central parahilar hematoma was visualized in all 5 cases with avulsion or disruption of renal pedicle vasculature. Although lack of contrast enhancement of injured renal parenchyma is a hall-mark of renal pedicle injury, three cases did not demonstrate this typical finding. In these three cases, one showed partial and the others showed total enhancement of the injured renal parenchyma on contrast enhanced CT. Partial enhancement in one case was found to represent total occlusion of the main renal artery and an intact accessory polar branch on angiography. The other two cases showed total enhancement of the renal parenchyma, with renal vein perforation done and complete disruption of the main renal artery and vein in the other. The latter findings were thought to be due to the maintenance of vascular flow surrounded by hematoma. In conclusion, when central parahilar hematoma is identified, the possibility of renal pedicle injury should be considered even if the renal parenchyma is well enhanced.

Multicenter genetic study of retinitis pigmentosa in Japan: II. Prevalence of autosomal recessive retinitis pigmentosa

Retinitis pigmentosa (RP) is a group of genetically heterogeneous diseases with autosomal recessive (AR), autosomal dominant, and X-linked modes of inheritance. Autosomal recessive retinitis pigmentosa (ARRP) is the most common form in Japan. A genetic analysis was done to determine the prevalence of ARRP indirectly, to provide an estimation of changing trends in the overall prevalence of RP. Data on the frequency of consanguinity and marriage year of normal parents of 59 ARRP patients were obtained from a nationwide multicenter survey of typical retinitis pigmentosa conducted in 1990. The gene frequency of ARRP was 0.01145 (Dahlberg's formula). In 1990, the number of young symptomatic ARRP patients decreased, while the number of patients aged 40 years and older increased. The total number of symptomatic ARRP patients in 1990 was nearly 21% higher than in 1970. Despite a dramatic decline in consanguinity in recent decades in Japan, the number of ARRP patients has increased. This increase is attributed to greater longevity and overall population growth. Our results suggest that the total number of RP patients has not decreased, and may even have increased.

[Urinary neopterin levels in patients with genitourinary tract malignancies]

BACKGROUND

Neopterin is released from macrophages upon stimulation with gamma-interferon, secreted by activated T cell. Therefore it has been recognized as a useful indicator of the activation of the T cell-macrophage system. Increased neopterin levels are observed in patients with acute graft rejections, viral infections, auto-immune diseases and several malignancies. Urinary neopterin concentrations were determined in patients with genitourinary tract malignancies to evaluate the usefulness of neopterin as a tumor marker.

METHODS

Urinary neopterin concentrations were determined by high-performance liquid chromatography in 90 patients with genitourinary tract malignancies and 28 patients with benign urological tumors and 34 healthy subjects.

RESULTS

Increased urinary neopterin levels were observed in 52% of the patients with genitourinary tract malignancies and 7% with benign urological tumors. The positivity rate in patients with renal cell carcinoma (RCC), renal pelvic and ureteral tumor, bladder tumor (BT), prostatic carcinoma (PC) and testicular tumor was 68%, 80%, 47% and 30%, respectively. The difference in the urinary neopterin levels between low and high stages was highly significant (p < 0.0005) in patients with RCC (stage I-II vs. stage III-IV) and BT (T1S-1 VS. T2-4). The urinary neopterin levels were also correlated with the tumor grade in patients with RCC and PC.

CONCLUSION

Our study suggests that urinary neopterin levels may supplement laboratory examinations for patients with genitourinary tract malignancies, providing useful information in evaluating the tumor stage and follow-up of the disease.

A new genus of the order Actinomycetales, Spirilliplanes gen. nov., with description of Spirilliplanes yamanashiensis sp. nov

Actinomycete strain YU127-1T (T = type strain), which produces zoospores, was isolated from a soil sample. The aerial mycelium of this organism at maturity forms short chains of spores. The hyphae form coils, and sporangia are not observed. Strain YU127-1T contains glutamic acid, glucosamine, glycine, alanine, and meso-diaminopimelic acid in its cell wall (wall chemotype II), 3-O-methylmannose, mannose, xylose, and glucose as whole-cell sugars, meanaquinone 10(H4), and glycolyl cell wall polysaccharides and has a guanine-plus-cytosine content of 69.0 mol%. Mycolic acids are absent. Phosphatidylinositol and phosphatidylethanolamine are diagnostic phospholipids. The chemotaxonomic data, except for the lack of arabinose in the whole-cell sugars, indicate that this strain belongs to the family Micromonosporaceae. The morphological and physiological characteristics and chemotaxonomic and phylogenetic data for this strain differ from those of the previously described actinomycetes. We therefore propose a new genus, spirilliplanes, for this organism; the type species of the genus is Spirilliplanes yamanashiensis sp. nov., and the type strain of S. yamanashiensis is strain YU127-1 (= IFO 15828).

[Evidence for association between renal cell carcinomas and renal cystic diseases: nationwide survey in Japan]

OBJECTIVE

A scanty evidence previously reported regarding renal cell carcinomas occurring in association with renal cystic diseases prompted us to conduct a nationwide survey in July 1991.

METHODS

A total of 507 hospitals responded to the questionnaire inquiring the clinical and pathological characteristics of renal cell carcinoma associated with renal cystic diseases over the previous 2 years.

RESULTS

Renal cystic diseases were identified in 223 (3.9%) of 5,721 patients with renal cell carcinoma. The patients consisted of 181 men and 42 women who had a mean age of 55.2 +/- 12.5 years (SD). The renal cystic diseases comprised simple renal cysts in 72 patients (32%), acquired cystic diseases of the kidney (ACDK) in 62 (28%), cystic renal cell carcinoma in 56 (25%), multilocular renal cysts in 20 (9%), polycystic kidney in 3 (1.3%), miscellaneous cysts in 9 (4.0%), and unspecified cysts in 1 (0.4%). Simple renal cysts were more common in older patients, while ACDK and multilocular cysts were more predominant in younger patients. They included 71 dialysis patients (32%), of whom 62 (87%) had ACDK. Renal cell carcinoma occurred bilaterally in 12 patients (17%) on dialysis. Young male patients over a longer dialysis period were more susceptible to renal cell carcinoma. Low stage tumor, papillary type and granular cell subtype were more common in those on dialysis than in those without dialysis. In consideration of the Japanese general and dialysis population, we confirmed that dialysis patients with ACDK are more susceptible to renal cell carcinoma and those with polycystic kidney are less so.

CONCLUSION

Renal cystic diseases may be associated with about 4% of renal carcinoma. Young male patients over a longer dialysis period who are diagnosed to have renal cysts should be regularly and closely followed by imaging study.

Intraductal papillary adenocarcinoma with mucin hypersecretion and coexistent invasive ductal carcinoma of the pancreas with apparent topographic separation

We report a 66-year-old man who had a cystic intraductal papillary adenocarcinoma containing a papillary adenoma, in the head of the pancreas and a coexistent invasive, well differentiated solid tubular adenocarcinoma in the tail of the pancreas. He was hospitalized with acute epigastralgia. Computed tomography demonstrated a multilocular cystic mass in the head of the pancreas and a solid tumor in the tail. Endoscopic retrograde pancreatography showed mucin secretion from an enlarged papilla of Vater, marked dilatation of the main pancreatic duct in the head and body, cystic dilatation of the uncinate branch, and irregular narrowing of the main pancreatic duct in the tail. Total pancreatectomy was performed. Between the cystic tumor and the solid tumor there was a distance of 4.8 cm of normal pancreatic parenchyma and duct, recognized both grossly and microscopically. The patient died 35 months after the operation. At autopsy, peritonitis carcinomatosa was found in the abdominal cavity. Microscopically, disseminated nodules were also well differentiated tubular adenocarcinoma. The apparent anatomic separation of these two tumors within the pancreas is extremely unusual.

[Rapidly progressive glomerulonephritis associated with myeloperoxidase specific-antineutrophil cytoplasmic antibody in patients with rheumatoid arthritis : report of three cases]

The reports on the patients with rheumatoid arthritis (RA) complicated with the myeloperoxidase specific-antineutrophil cytoplasmic antibody (MPO-ANCA) associated glomerulonephritis, whose clinical feature is rapidly progressive glomerulonephritis (RPGN), have been rare. We here report three cases of RPGN with MPO-ANCA in RA patients. Case 1. A 44-year-old woman with RA for 25 years was admitted because of RPGN. The level of MPO-ANCA was markedly high (293 EU) and the histological examination of the kidney showed diffuse crescentic glomerulonephritis. In spite of the intensive immunosuppressive therapy, her renal function did not recover and she underwent hemodialysis (HD). Case 2. A 58-year-old man with RA for 5 years was admitted due to RPGN (MPO-ANCA ; 147 EU, Ccr ; 16 ml/min) with the nephrotic syndrome and fever. The treatment with the immunosuppressive agents and the plasma exchange was partially effective to stop the rapid progression of the disease, but a few months later, his renal function worsened (Ccr 7 ml/min). A recent histological examination of the kidney failed to establish the CrGN because of endstage kidney. Case 3. A 56-year-old woman with RA for the past 10 years was admitted because of RPGN (MPO-ANCA ; 652EU). Intensive therapy could not be performed because of an active duodenal ulcer and markedly impaired renal function (Ccr ; 6 ml/min), and soon she underwent HD. Renal biopsy was not done. These three cases suggest that RPGN can occur in part of RA patients with MPO-ANCA.

Estimation of fat absorption with the 13C-trioctanoin breath test after pancreatoduodenectomy or pancreatic head resection

The aim of this study was to determine if fat absorption is better after pylorus-preserving pancreatoduodenectomy (PPPD) or duodenum-preserving pancreatic head resection (DPPHR) compared with that following pancreatoduodenectomy with gastrectomy (SPD), provided the patients have similar pancreatic exocrine function. Fat absorption was studied using the 13C-trioctanoin breath test in patients who were grouped according to the degree of fibrosis of the pancreatic remnant. The latter was judged by histologically measuring the fibrosis in a transectional wedge of resected pancreas. We evaluated 11 SPD cases, 25 PPPD cases, and 9 DPPHR cases. The 13C excretion rates and cumulative excretion values following DPPHR or PPPD were significantly better than those following SPD. The 13C excretion rates and cumulative values for the patients with > 30% fibrosis of the pancreas were lower than those in patients with < 30% pancreatic fibrosis, regardless of the surgical procedure. The cumulative value in the SPD group, however, was lower than that in the PPPD or DPPHR patients with < 30% pancreatic fibrosis. The results suggested that fat absorption following PPPD or DPPHR is superior to that after SPD in patients with the same fibrotic area of the pancreatic remnant and depends on the degree of fibrosis in the pancreatic remnant.

Effects of ubiquinone enriched diet on deterioration of mitochondrial respiratory function caused by fried beef derived mutagenic factor in rats

2-Amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP), a potent mutagenic agent produced during thermal processing of meats, shows detrimental effects on mitochondrial respiratory function. Effects of dietary ubiquinone-10 was examined on PhIP-induced mitochondrial respiratory dysfunction in rats. Rats fed with 0.2% ubiquinone-10 diet mitigated the PhIP-induced decrease in mitochondrial complex I activities observed in rat heart, diaphragm, and psoai major. Therefore, dietary anti-oxidants such as ubiquinone-10 could cancel out the unfavorable effects of PhIP and contribute to the preservation of mitochondrial function.

Surgical treatment of internal carotid siphon aneurysms

Surgical treatment of internal carotid artery aneurysms around the carotid siphon is discussed. The surgical approach to the aneurysms in this region, is as follows: 1. A fronto-temporal approach with the patient in a 45 degrees semi-sitting position to decrease venous pressure. 2. A Dolenc approach cutting a part of the dura mater of the superior orbital fissure to facilitate removal of the anterior clinoid process and unroofing of the optic canal. 3. Opening the medial triangle followed by transection of the optic canal dural sheath. Carotid siphon aneurysms can be divided into three groups anatomically; aneurysms of the ophthalmic segment (C2), those of the clinoid segment (C3), and those of the horizontal segment (C4). We present 29 cases of aneurysms arising from the C2 or C2/3 segment, 14 cases arising from the C3 or C3/4 segment, and 11 cases arising from the C4 segment. Anatomic localization of the aneurysms was established preoperatively by angiography and three-dimensional CT imaging. Small aneurysms of the ophthalmic segment projecting infero-medially can be clipped using a contralateral approach via the prechiasmatic root. Aneurysms of the ophthalmic segment projecting superiorly can be clipped following resection of the anterior clinoid process. The clinoid process should be resected intradurally with direct visualization of the aneurysms. Straight side-angled clips are suitable for these aneurysms. Carotid cave aneurysms, which include aneurysms of the ophthalmic segment oriented infero-medially and of the clinoid segment projecting postero-medially, can be clipped using curved fenestrated clips via Dolenc's extradural approach. For accurate clipping, opening of the medial triangle and full mobilization of the IC at the clinoid segment and optic nerve by unroofing the optic canal are required. Aneurysms of the horizontal portion are clipped after full exposure of the artery in the cavernous sinus only when the aneurysms are large and symptomatic. We used the fronto-temporal and Dolenc approaches and applied fenestrated clips to aneurysms oriented or postero-medially and straight or oblique clips to aneurysms projecting antero-laterally. Out of 40 aneurysms which underwent surgical clipping, 37 resulted in good post-operative recovery. There were three deaths secondary to complications of vasospasm and three cases with post-operative visual loss. The classification of these aneurysms and the surgical techniques we employed are discussed in detail.

Age-related extensive fragmentation of mitochondrial DNA into minicircles

In normal human hearts, a progressive age-related fragmentation of mitochondrial (mt) DNA into various-sized deleted (delta) mtDNA up to 358 types was documented by a novel total-detection system for deletions. The delta mtDNA lacking replication origin(s), minicircles, accumulated up to 280 types out of the 358, suggesting a yet unknown replication mechanism in human. Wild-type mtDNA decreased linearly down to 11% of the total with age negatively correlated with delta mtDNA and oxidized nucleoside, 8-hydroxydeoxyguanosine. A remarkable mirror image observed in delta mtDNA size distribution as well implies that random hydroxyl-radical attacks resulted in double-strand break and rejoining of mtDNA as a preferable mechanism to form various delta mtDNA of closed circular duplex. These facts support the 'redox mechanism of aging.'