Lower Triassic stromatolites in Luodian County, Guizhou Province, South China: evidence for the protracted devastation of the marine environments.

Stromatolites are one of the oldest and most intriguing organosedimentary deposits. In contrast to stromatolites of the Precambrian to Early Ordovician, Phanerozoic equivalents occurred episodically under specific conditions. A group of previously undescribed stromatolites in composition occur in the Lower Triassic (Olenekian) at the Dajiang section in the Luodian region of Guizhou Province, South China. We described the textures of these stromatolites with the aim of determining the genetic mechanisms and revealing the nature of interactions between micro-organisms and marine environments. Mesoscopic features show that the stromatolites consist of several sets of stacked slices, and that they are embedded in alternating beds of fine and coarse microsphere packstones that include aggregates of microspheres, forming grapestones and lumps. Microscopically, the stromatolites consist of spar- and dolomite-infilled microspheres (average diameter, 100 µm), micrites, peloids, small-sized pyrite framboids (average diameter, 5.8 µm) and fenestrae. Micrite-dominant intercalations accentuate laminated textures at a mesoscopic level and are laterally continuous with micrite-rich parts in surrounding interstromatolites, indicating the simultaneous, widespread deposition of these layers. The microspheres and associated micrites were the products of in situ microbial activity, probably sulphate-reducing or anoxygenic phototrophic bacteria, which led to the formation of these unusual stromatolites. Even during a protracted period of harsh marine conditions, the micrite-rich carpets were deposited intermittently on the stromatolites and their surroundings under severely anoxic/sulphidic conditions. The presence of Early Triassic stromatolites and their subtle but important vertical variations in texture provide a record of temporal changes in marine conditions during geobiologically critical intervals.

Role of diffusion-weighted magnetic resonance imaging in diffuse axonal injury.

PURPOSE: To determine whether the signal changes on magnetic resonance imaging (MRI), including fluid attenuated inversion recovery (FLAIR), T2*-weighted gradient echo (GE) imaging, and diffusion-weighted imaging (DWI) in diffuse axonal injury (DAI) patients correlate with the clinical outcome. MATERIAL AND METHODS: We diagnosed patients with DAI based on the following criteria: 1) a loss of consciousness from the time of injury that persisted beyond 6 h; 2) no apparent hemorrhagic contusion on computed tomography (CT); 3) the presence of white matter injury on MRI. Twenty-one DAI patients were analyzed (19 M, 2 F, mean age 34 years) with MRI (FLAIR, T2*-weighted GE imaging, and DWI). RESULTS: 325 abnormalities were detected by MRI within a week after injury. The T2*-weighted GE imaging was significantly more sensitive than FLAIR and DWI in diagnosing DAI. DWI detected only 32% of all lesions, but could depict additional shearing injuries not visible on either T2*-weighted GE imaging or FLAIR. The mean number of lesions in brainstem detected by DWI in the favorable group (good recovery/moderately disabled) was significantly smaller than in the unfavorable group (severely disabled/vegetative survival/death). This trend was not observed on the T2*-weighted GE imaging and FLAIR findings. CONCLUSION: DWI cannot detect all DAI-related lesions, but is a potentially useful imaging modality for both diagnosing and assessing patients with DAI.

Lesions identified on T2*-weighted gradient echo images in two patients with suspected diffuse axonal injury that resolved in less than ten days.

T2*-weighted gradient echo (GE) imaging is useful for detection of intracranial hemorrhage in the patients with diffusion axonal injury (DAI). However, the temporal changes in the DAI-related lesions on T2*-weighted GE images are not clear. We report two very rare cases with DAI in which lesions identified on T2*-weighted GE images resolved in less than ten days.

[A case of malignant lymphoma concomitant with multiple myeloma].

A 75-year-old woman was referred to us because of cough, high fever and skin erythema in April 1999. Malignant lymphoma (diffuse mixed cell type) was previously diagnosed in 1990 and she achieved complete remission after treatment with a series of CHOP regimen treatments. In 1998, multiple myeloma (IgG lambda type) was diagnosed and she was treated with a combination of melphalan and prednisolone. On physical examination, superficial lymphadenopathy and skin erythema were noted. Biclonal gammopathy (IgG kappa/lambda) was shown in serum, and Bence Jones protein in urine. Computed tomography showed pleural effusion and swelling of paraaortic lymph nodes. The bone marrow examination showed an increased number of abnormal plasma cells (19.2%) and no evidence of lymphoma. Left axillary lymph node biopsy revealed that she had non-Hodgkin's lymphoma (immunoblastic lymphadenopathy-like T cell lymphoma). She was treated with the CHOP regimen at reduced doses for both diseases. The lymphoadenopathy reduced after 6 courses of CHOP and 4 courses of CHOPE (CHOP + VP16), however, she had bone pain on November 1999 and received treatment with MCNU-VMP (MCNU + VDS + L-PAM + PSL). Her rib pain improved, but she died of systemic infection of herpes zoster virus. We report here a rare case of malignant lymphoma concomitant with multiple myeloma.

[An autopsied case of marked cardiac hypertrophy due to multifactorial heart disease in an 85 year-old man who had been socially active].

An autopsied 85-year-old man had suffered from a mild form of diabetes mellitus since the age of 67 and had experienced the first episode of heart failure with arapid ventricular rate of atrial fibrillation at the age of 72. He had remained socially active until he died suddenly of ventricular fibrillation, although he had complications of aortic regurgitation at the age of 76 and later mitral regurgitation at the age of 80. Chest roentgenograms showed gradual increase in the cardiothoratic ratio which reached 68.1% at the final stage. Autopsy revealedmarked left ventricular hypertrophy with a heart weight of 580 g, degeneration ofaortic valves, thickening of mitralvalve cusps and moderate coronary atherosclerosis without ischemic myocardial lesions. There were no specific lesions suggestive of primary cardiomyopathies on microscopic observations and the lesions of both aortic and mitral valves were not significant enough to explain the clinical findings of aortic and mitral regurgitation. Because the pathological examination failed to identify a single disease which was responsible for the marked cardiachypertrophy, we eventually reached the conclusion that the cardiac hypertrophy developed based on a multifactorial heart disease.

Expression of aluminum-induced genes in transgenic arabidopsis plants can ameliorate aluminum stress and/or oxidative stress.

To examine the biological role of Al-stress-induced genes, nine genes derived from Arabidopsis, tobacco (Nicotiana tabacum L.), wheat (Triticum aestivum L.), and yeast (Saccharomyces cerevisiae) were expressed in Arabidopsis ecotype Landsberg. Lines containing eight of these genes were phenotypically normal and were tested in root elongation assays for their sensitivity to Al, Cd, Cu, Na, Zn, and to oxidative stresses. An Arabidopsis blue-copper-binding protein gene (AtBCB), a tobacco glutathione S-transferase gene (parB), a tobacco peroxidase gene (NtPox), and a tobacco GDP-dissociation inhibitor gene (NtGDI1) conferred a degree of resistance to Al. Two of these genes, AtBCB and parB, and a peroxidase gene from Arabidopsis (AtPox) also showed increased resistance to oxidative stress induced by diamide, while parB conferred resistance to Cu and Na. Al content of Al-treated root tips was reduced in the four Al-resistant plant lines compared with wild-type Ler-0, as judged by morin staining. All four Al-resistant lines also showed reduced staining of roots with 2',7'-dichloro fluorescein diacetate (H(2)DCFDA), an indicator of oxidative stress. We conclude that Al-induced genes can serve to protect against Al toxicity, and also provide genetic evidence for a link between Al stress and oxidative stress in plants.

Insertion/deletion polymorphism in the angiotensin-converting enzyme gene affects heart weight.

BACKGROUND: Angiotensin (Ang) II, a major regulatory factor for left ventricular mass, is generated from Ang I by ACE. ACE levels are associated with an insertion/deletion (I/D) polymorphism in the ACE gene. The ACE polymorphism should result in varied Ang II concentrations and hence affect left ventricular mass. We therefore investigated whether ACE genotype is a predictor of heart weight. METHODS AND RESULTS: From 693 consecutive patients autopsied between 1994 and 1998 in our hospital, patients with valvular disease, myocardial infarction, or cardiomyopathy were excluded. The remaining 443 autopsy patients were the subjects of our study. The heart weight at autopsy was corrected for body surface area. Genomic DNA was purified from the kidney, and ACE genotype was determined by polymerase chain reaction. Heart weight in the DD genotype (249. 9+/-49.9 g/m(2)) was significantly higher than that in the ID (230. 0+/-51.2 g/m(2); P<0.05) and II (226.8+/-49.8 g/m(2); P<0.01) genotypes. Heart weight was also positively related to age (r=0.145, P<0.0001) and coronary stenosis index (r=0.147, P=0.0019). Multiple regression analysis showed that a history of hypertension (P<0.0001), age (P=0.0001), and DD genotype (P=0.0154) were independent predictors of heart weight. CONCLUSIONS: ACE genotype predicts cardiac mass; however, it was less effective than epigenetic factors such as hypertension or age.

[Focal segmental glomerulosclerosis associated with type C virus hepatitis and decrement of proteinuria by interferon-alpha therapy].

Focal segmental glomerulosclerosis (FSGS) associated with type C virus (HCV) hepatitis has not been described in the literature to date. However, we experienced a 30-year-old man, who had had HCV hepatitis, developed nephrotic syndrome and was admitted to our hospital. The first renal biopsy showed FSGS which was diagnosed by light, immunofluorescent, and electron microscopic study. FSGS diagnosis was based upon the findings of focal segmental glomerular sclerosis associated with hyalinosis and foam cells, segmental deposition of IgM and C3 on glomeruli, and epithelial cell vacuolization in the Bowman's space. HCV hepatitis was treated with interferon-alpha (INF-alpha) over 6 months. The treatment brought the disappearance of not only HCV-RNA from the blood, but also the manifestation of nephrotic syndrome. Therefore, the second renal biopsy was performed, but did not reveal any great pathological improvement. Five months later after the remission, he again had an elevated HCV-RNA level and a relapse of nephrotic syndrome. He was retreated with the same therapy and achieved a second remission of nephrotic syndrome. FSGS associated with HCV hepatitis is described first and the implication of INF-therapy in the improvement of proteinuria is discussed.

Acquisition of aluminum tolerance in Saccharomyces cerevisiae by expression of the BCB or NtGDI1 gene derived from plants.

Eleven aluminum stress-induced genes derived from plants (wheat, Arabidopsis and tobacco) were introduced into Saccharomyces cerevisiae to test if expression of these genes confers Al tolerance. Al sensitivity tests showed that expression of two genes, either an Arabidopsis gene for blue copper binding protein (BCB), or a tobacco gene for the GDP dissociation inhibitor (NtGDI1), conferred Al tolerance. Determinations of total content and localization of Al ions in these transformants suggested that the BCB gene product functions in restricting Al uptake, while expression of the NtGDI1 gene promotes release of Al ions after uptake.

Raman scattering tensors of tyrosine.

Polarized Raman scattering measurements have been made of a single crystal of L-tyrosine by the use of a Raman microscope with the 488.0-nm exciting beam from an argon ion laser. The L-tyrosine crystal belongs to the space group P2(1)2(1)2(1) (orthorhombic), and Raman scattering intensities corresponding to the aa, bb, cc, ab and ac components of the crystal Raman tensor have been determined for each prominent Raman band. A similar set of measurements has been made of L-tyrosine-d4, in which four hydrogen atoms on the benzene ring are replaced by deuterium atoms. The effects of NH3-->ND3 and OH-->OD on the Raman spectrum have also been examined. In addition, depolarization ratios of some bands of L-tyrosine in aqueous solutions of pH 13 and pH 1 were examined. For comparison with these experimental results, on the other hand, ab initio molecular orbital calculations have been made of the normal modes of vibration and their associated polarizability oscillations of the L-tyrosine molecule. On the basis of these experimental data and by referring to the results of the calculations, discussions have been presented on the Raman tensors associated to some Raman bands, including those at 829 cm-1 (benzene ring breathing), 642 cm-1 (benzene ring deformation), and 432 cm-1 (C alpha-C beta-C gamma bending).

Protective roles of two aluminum (Al)-induced genes, HSP150 and SED1 of Saccharomyces cerevisiae, in Al and oxidative stresses.

We isolated two yeast cDNA clones whose transcripts are induced by aluminum (Al) metal stress. Partial nucleotide sequencing showed that one is the HSP150 gene encoding a secreted heat shock protein, and the other corresponds to the SED1 gene encoding a putative membrane protein. To clarify the biological functions of these genes, we analyzed the sensitivity of gene-disrupted mutants to Al stress and to oxidative stresses. The Al tests indicated that the HSP150 protein served a basal protective role in Al stress, but SED1 did not; both of the genes had protective roles for oxidative stresses. The results for the HSP150 gene suggest that there is an overlap between Al ion stress, oxidative stress and heat shock stress in yeast.

[Relation of asymptomatic myocardial ischemia to impaired communication, cerebrovascular disease, and lack of ability to perform activities of daily living in elderly patients].

Patient's reports of angina pectoris depend on cognition and communication, and on the patient's physical and mental activity. In elderly people, these functions are often impaired, and we therefore looked for evidence of myocardial ischemia in 770 consecutive autopsies. We defined the coronary stenosis index (CSI) as the sum of the stenosis scores of three coronary arteries: 0% = 1, 25% = 2, 50% = 3, 75% = 4, 90% = 4.5 95 or 100% = 5. A total score of more than 13.0 and a score of 5.0 in one vessel was assumed to have been associated with myocardial ischemia. Patients assumed to have had myocardial ischemia were classified according to the presence or absence of angina pectoris: 24 had angina pectoris and 92 were asymptomatic. As controls, 86 patients in whom the CSI was lower than 10.0 were studied. Death due to myocardial infarction was most frequent in patients with angina (67%). Acute myocardial infarction was more common in asymptomatic patients than in controls (27% vs. 1%). Small myocardial infarctions and inferior myocardial infarctions were more frequent in asymptomatic patients than in those with angina. Cerebrovascular disease, problems doing activities of daily living, and communication disturbance were more common in asymptomatic patients than in those with angina. Electrocardiographic evidence of an old myocardial infarction was found in 40.9%, 16.6%, and 2.3% of patients with angina, asymptomatic patients, and controls, respectively (p < 0.05). Morphologic details of the myocardial infarction, coexistence of cerebrovascular disease, inability to perform activities of daily living, and impaired communication are associated with asymptomatic myocardial ischemia. Patients with asymptomatic myocardial ischemia should be identified and treated because of their relatively poor prognosis. Ischemic events might be detected by careful observation and prevented by appropriate treatment.

[Gastric cancer in the elderly].

Gastric cancer in the elderly was evaluated with regard to age-related pathomorphological changes. Resected gastric cancer was studied with regard to location, stage, morphology and histology in male young old (65-74 years old) which were 25 cases and 31 lesions, respectively male middle old (75-84 years old); 104 cases and 120 lesions, male very old (85 years-); 96 cases and 110 lesions, female young old; 22 cases and 31 lesions, female middle old; 91 cases and 106 lesions, female very old; 51 cases and 55 lesions. Multiple gastric cancers were more frequent in female older group. In early cancer the frequency of elevated type increased significantly and that of depressed type decreased in very old group. In advanced cancer Borrmann I type was not so common in very old group. Histologically the frequency of signet ring cell cancer decreased and of tubular adenocarcinoma and of papillary adenocarcinoma increased significantly in female very old group. Hepatic metastasis increased significantly in male very old group. Lymph node metastasis and peritoneal metastasis did not show any change in age-related frequency.

[Morphometric study of age-related changes of the spinal cord].

The relation of aging to the length of the spinal cord and to the cross-sectional area at the levels of C6 and L3 of the spinal cord was studied in 140 autopsy cases who between the age of 47 to 105 without spinal cord lesions. In addition the effect of being bed-ridden on the spinal cord was studied in 11 of 140 cases. As pathological controls, we referred to 40 autopsy cases with compression change of the cervical cord. The length of the spinal cord had no correlation with aging but had a significant positive correlation with the height of the subject. A significant decrease in the cross-sectional area of the spinal cord was observed after the age of 80, in particular at C6. However, the extent of the decrease was not as serious as that of pathological control cases. Decrease of cross-sectional area was associated with that of white matter area. In addition, effect of being bed-ridden on the spinal cord was reflected in a significant decrease of the grey matter of the lumbar cord.

[Neuropathological study of amyotrophic lateral sclerosis in relation to aging].

It has been assumed that amyotrophic lateral sclerosis (ALS) involves precocious senility as one of its pathogenetic aspects. The authors studied 55 autopsied cases of ALS in relation to age at death, ranging from 42 to 86. The materials consisted of 8 cases in the fifth decade, 8 in the sixth, 20 in the seventh, 12 in the eighth, and 7 in the ninth. The total duration of illness ranged from 6 months to 14 years. The most distinct relationship was observed in the anterior horn lesion of the cervical enlargement which became less severe with advancing age, irrespective of the length of illness. Fifth decade cases showed marked atrophy with severe neuronal loss and fibrillary gliosis in the anterior horn, while those in the ninth decade showed slight changes which were similar to age-matched controls. On the other hand, pyramidal tract degeneration did not show any correlation to age at death or to length of illness. Pyramidal tract degeneration was found in all younger age group cases, being always severe. In the older age groups, however, the degeneration varied extremely in degree from case to case. Some cases showed severe degeneration comparable with that in the younger age groups, while the others had no findings suggesting degeneration. In addition, cases on artificial respirators had a longer duration of illness, and more marked degeneration in the anterior horn, irrespective of age. Our study did not reveal that senile changes including senile plaques and neurofibrillary tangles were more marked in ALS cases. No clinicopathological correlation with dementia was recognized.(ABSTRACT TRUNCATED AT 250 WORDS)

[Two autopsy cases of aortitis syndrome in the elderly].

Two autopsy cases of aortitis syndrome (Takayasu's aortitis) in the elderly are presented. Case 1 was an 81-year-old woman in whom hypertension was observed at age 37, and difference of right and left arm blood pressure was pointed out at age 65. She was referred to the authors' hospital at age 72. Chest X-ray and computed tomography of the thorax indicated atypical coarctation and diffuse calcification of the aorta. Case 2 was a 69-year-old woman in whom hypertension was pointed out at age 49, and blood pressure in the arms was found to differ from that in the legs at age 63. Chest X-ray and computed tomography showed diffuse calcification and marked narrowing of the descending aorta. Pathological examination revealed marked calcification in the thickened adventitia of the aorta with mild atherosclerotic change. Irregular fibrotic changes of the adventitia and degeneration of elastic fibers of the media of the aorta were noted in both cases, and were consistent with Takayasu's aortitis. This disorder is common in young women and only a small number of elderly cases are reported although its incidence is increasing. Diffuse calcification of the aorta with an absence of inflammatory signs, which is frequent in older patients, were observed in both case. Systemic hypertension is the most important risk factor with coarctation of the aorta in Takayasu's aortitis. Bypass surgery is recommended in young patients, however in elderly patients, it is generally avoided, in favor of medical control of hypertension.

[Diagnosis of paraaortic and pelvic lymph node metastasis by ultrasound guided percutaneous fine needle aspiration biopsy (FNAB)].

Ultrasonography (US) was performed in patients with gynecologic malignancies to detect paraaortic and pelvic lymphadenopathy. US of paraaortic lymph nodes was performed in 32 patients. Of the 32 patients 17 had lymphadenopathy, and ultrasound-guided percutaneous fine needle aspiration biopsies (FNAB) were therefore performed in 16 of these 17 cases. Of these 16 patients, 11 were positive and 5 were negative FNAB. US of pelvic lymph nodes was performed in 68 patients. Of the 68 patients 14 had lymphadenopathy, and FNAB were performed in 8 of these. All 14 of these FNABs were positive. There were no major complications from due to FNAB. It is therefore concluded that ultrasound-guided percutaneous FNAB is very useful in detecting metastatic lymph nodes of gynecologic malignancies.