Decrease in Activity of Glutathione Reductase Enhances Paraquat Sensitivity in Transgenic Nicotiana tabacum

Transgenic tobacco (Nicotiana tabacum L. cv SR1) with decreased activity of glutathione reductase exhibited enhanced sensitivity to paraquat in the light as evaluated by chlorophyll destruction and electrolyte leakage from leaf discs. This result indicates the involvement of glutathione reductase in the tolerance of plants to photooxidative stress caused by the herbicide.

Isolation and biological activity of thielocins: novel phospholipase A2 inhibitors produced by Thielavia terricola RF-143

Thielocins A2 alpha, A2 beta, A3, B1, B2 and B3 were isolated as a novel family of phospholipase A2 inhibitors from the fermentation broth of Thielavia terricola RF-143 together with thielavins and thielocins A1 alpha and A1 beta. The most potent inhibitory activity (IC50 = 0.0033 microM) against rat group II phospholipase A2 was shown by thielocin A1 beta. Against human group II phospholipase A2, thielocin B3 (IC50 = 0.076 microM) was the most potent.

Canine SPECT studies for cerebral amino acid transport by means of 123I-3-iodo-alpha-methyl-L-tyrosine and preliminary kinetic analysis

We have already reported that 123I-3-iodo-alpha-methyl-L-tyrosine (123I-L-AMT) is superior as a single-photon emitter labeled radiopharmaceutical reflecting cerebral amino acid transport. In this study, we investigated the distribution of 123I-L-AMT in the canine head by means of SPECT and kinetically analyzed the data in the brain. As a result, clear SPECT images of the canine brain were obtained. Kinetic analysis with a 2-compartment model, including or expressing membrane transport of the amino acid, was performed with time-activity curves in the arterial blood and in the cerebral region. The results of the analysis coincided closely with the experimental data and the relevance of the model was strongly suggested. Therefore 123I-L-AMT is considered to be useful as a single photon radiopharmaceutical which enables us to measure the cerebral amino acid transport rate.

Long term course of change in anti-Yo antibody content in paraneoplastic cerebellar degeneration

Images

[Is routine second-look operation justified for stage I ovarian cancer?]

The results and role of second-look operation (SLO) were evaluated in 33 patients with stage I epithelial ovarian cancer. 1. At SLO, histological evidence of disease was not identified in any of 24 patients, but washing cytology showed class III in 2 patients. 2. Only one (4.5%) patient with stage Ic (washing cytology: positive) has had a recurrence following negative SLO. 3. Recurrent tumor developed in 2 (33.3%) of the stage Ic (capsular invasion) patients and 1 (16.7%) of the stage Ic (washing cytology: positive) patient, but all patients with stage Ia or Ic (surgically ruptured by surgeon) are alive without recurrence. 4. Based on this experience, our current recommendation for patients with stage Ia or Ic (surgically ruptured by surgeon) epithelial ovarian cancer following comprehensive staging surgery and primary chemotherapy is that they do not require routine SLO.

[Study on the relationship between hormonal cytology and bone mineral density in postmenopausal women]

We assessed the relationship between bone mineral density (BMD) and hormonal cytology in 181 postmenopausal women. BMD was measured by dual energy X-ray absorptiometry (DXA). Age, height, weight, body mass index (BMI), age at menopause, hormonal cytology (eosinophilic index (EI), karyopyknotic index (KPI) and maturation value (MV)) and estradiol were investigated. A positive correlation was found between BMD and hormonal cytology (EI r = 0.17 p < 0.05, KPI r = 0.19 p < 0.05 and MV r = 0.37 p < 0.005). The low BMD group (BMD < 0.8g/cm2 n = 87) had significantly lower hormonal cytology than the normal BMD group (BMD > or = 0.8g/cm2 n = 94). The receiver operating characteristic curve analysis showed MV at 30 was available for the cutoff point in predicting osteopenia. MV < 30 detected osteopenia (BMD < 0.8g/cm2) as 0.76 in sensitivity and 0.65 in specificity. These findings suggest that hormonal cytology is useful for screening osteopenia in post-menopausal women.

Living-related liver transplantation in adult recipients: a hypothesis

Living-related liver transplantation (LRLT) in pediatric recipients has been successful with 90% 1-year survival (1, 2). LRLT in adults is yet to succeed. We hypothesize a management strategy based on the donor graft weight-to-recipient body weight ratio (GRBWR) and the Redox Tolerance Index (RTI) (3). Favorable recipients (GRBWR above 0.7%) are candidates for left liver orthotopic transplantation. Unfavorable recipients (GRBWR 0.5-0.7% and RTI above 0.5%) are suitable for left liver auxiliary-orthotopic transplantation. Compromized recipients (GRBWR below 0.5% or RTI below 0.5%) might be suitable for a left liver auxiliary-heterotopic transplantation. The above hypothesis remains to be validated.

[Detected Epstein-Barr virus genome using polymerase chain reaction in peripheral mononuclear cells--subacute necrotizing lymphadenitis]

A 23-year old woman was admitted to our hospital because of fever, leukocytopenia, thrombocytopenia and cervical lymphadenopathy. From pathological findings of the cervical lymphnode she was diagnosed as subacute necrotizing lymphadenitis (SNL). Bone marrow aspiration was hypocellular with proliferation of mature histiocytes with hemophagocytosis. Lactate dehydrogenase was elevated to 1863 IU/l and mild liver dysfunction was observed. Hepatosplenomegaly, lymphnode swelling in abdominal cavity, pleural effusion and pericardial effusion were detected. After glucocorticoid therapy all such disorders were normalized. In this course, Epstein-Barr (EB) virus genome was detected by a polymerase chain reaction method from peripheral mononuclear cells. After normalization, EB virus genome became not to be detected. From present case we concluded that EB virus was expanded in clinical course and was associated with pathogenesis of SNL.

[A sporadic dentatorubral-pallidoluysian atrophy (DRPLA) diagnosed by gene analysis]

We report a 48-year-old woman with dentatorubral-pallidoluysian atrophy (DRPLA). She is the only patient in her 15 family members in two generations. She developed cerebellar ataxia and epilepsy at age 43. On admission at 48, she showed mild dementia and choreic movement in her face and extremities as well as truncal and limb ataxia. Routine laboratory examinations were normal. The point mutations in the tRNALys gene of mitochondrial DNA specific for MERRF were not found. A cranial CT scan and MRI showed mild atrophy of the cerebellum and prominent atrophy in the pons, especially in the tegmentum. Although she was thought to have DRPLA from the clinical point of view, absence of family history made the diagnosis difficult. Her parents were healthy until their 80's and died of cerebrovascular diseases and her 5 siblings had no symptoms. Hereditary DRPLA is known as an autosomal dominant disorder, with a high rate of penetrance and low rate of new mutation. According to our recent findings of a CAG repeat expansion in the DRPLA gene, this patient was diagnosed as a sporadic DRPLA. Considering the wide varieties of clinical manifestations, it is essential to examine this gene abnormality for diagnosing sporadic DRPLA.

Analysis of the chromosomal localization of the repetitive sequences (RPSs) in Candida albicans

The location and organization of repetitive sequences, members of the RPS family, which are sequences specific to Candida albicans, were determined on each chromosome of C. albicans strain FC18. Using pulsed-field gel electrophoresis, we separated seven fractions from eight chromosomes. Each chromosome was cleaved by BamHI and XhoI to excise the RPSs, which were then detected by hybridization with an RPS probe. All chromosomes except chromosome 4 carried RPSs, and these RPSs were located within a limited region on each chromosome. From the digestion of each chromosome with SfiI and probing with the RPSs, we found that these recognition sites within the RPS region were conserved among all RPS-containing chromosomes. For further characterization of the RPSs, the locations and the boundary regions of the RPSs were examined on chromosome 6 of strain FC18 as a model chromosome. Using the restriction enzymes SfiI, SmaI, XhoI, BamHI, MluI and NruI, we constructed a semi-macro physical map of the RPSs and their boundary regions on this chromosome. We also determined which part of the RPS was adjacent to each boundary by using sub-fragments of RPS as probes. The physical configuration around the RPSs and their boundary regions are presented. The results obtained should be useful for future analysis of the function of these regions.

Studies on metabolites of mycoparasitic fungi. II. Metabolites of Trichoderma koningii

Four peptaibols, named trichokonins (TKs) V, VI, VII, and VIII, were isolated from the culture broth of Trichoderma koningii Oudemans. Primary structures of these peptaibols were elucidated by electrospray ionization mass spectrometry (ESI-MS), FAB-MS, and collision-induced dissociation (CID) techniques along with nuclear Overhauser enhancement spectroscopy (NOESY).

Effects of nitric oxide synthase inhibitors on murine infection with Mycobacterium tuberculosis

We have recently demonstrated that the macrophage L-arginine-dependent cytotoxic pathway effectively kills the virulent Erdman strain of Mycobacterium tuberculosis in vitro via the generation of toxic reactive nitrogen intermediates by the enzyme nitric oxide synthase. This report demonstrates that two distinct inhibitors of nitric oxide synthase (aminoguanidine and NG-monomethyl-L-arginine) render similar deleterious effects on tuberculous infection in mice, as assessed by mortality, bacterial burden, and pathological tissue damage, thus confirming the importance of reactive nitrogen intermediates in resistance against M. tuberculosis.

Human histocompatibility leukocyte antigen-DR and heat shock protein-70 expression in eye muscle tissue in thyroid-associated ophthalmopathy

To investigate the expression and localization of human leukocyte antigen (HLA)-DR and heat shock protein-70 (HSP-70) in orbital tissue from patients with thyroid-associated ophthalmopathy (TAO), we carried out an immunohistochemical study using anti-HLA-DR and anti-HSP-70 monoclonal antibodies and a streptavidin-biotinperoxidase detection system. Eye muscle tissues were obtained at surgery from 38 patients with TAO and 8 control subjects. HLA-DR expression on eye muscle cells was demonstrated in orbital tissue from 2 of 3 untreated patients and 2 of 35 patients who had been treated with orbital irradiation or corticosteroids, in all of whom lymphocytic infiltration was also demonstrated. HLA-DR was not detected on eye muscle cells from 8 normal controls studied. HLA-DR was expressed on endothelial cells and interstitial cells from almost all patients with TAO and all 8 control subjects. HSP-70 was detected in eye muscle cells from 31 of the patients with TAO, including all 3 untreated patients, and 3 of the controls. Although the degree of HSP-70 expression did not correlate with the severity of the ophthalmopathy, significant expression of HSP-70 in eye muscle cells was more often demonstrated in patients with eye disease of short duration (83%) than in those with disease of longer duration (33%). These results support the notion that eye muscle fiber is an important target of the orbital autoimmune reactions that characterize TAO.

Trial to establish an animal model of paraneoplastic cerebellar degeneration with anti-Yo antibody. 2. Passive transfer of murine mononuclear cells activated with recombinant Yo protein to paraneoplastic cerebellar degeneration lymphocytes in severe combined immunodeficiency mice

Passive transfer of serum IgG or mononuclear cells from peripheral blood of a patient with paraneoplastic cerebellar degeneration (PCD) to rodents was carried out in order to examine the role of anti-Purkinje cell antibody (anti-Yo antibody) present in serum and cerebrospinal fluid of PCD patients. After a single injection of IgG into mouse brain, it was taken up by Purkinje cells and remained there for more than 36 h without Purkinje cell loss. Injection of PCD IgG together with complement or lipopolysaccharide-activated human macrophages or rat mononuclear cells into rat ventricles did not cause Purkinje cell loss. We also studied passive transfer of the PCD patient's lymphocytes to mice with severe combined immunodeficiency (SCID). We constructed a recombinant Yo fusion protein that has the leucine-zipper protein (Yo protein), the common epitope for anti-Yo antibody for immunizing mice, and that resulted in production of significant amounts of anti-Yo antibody. Spleen cells from these Yo protein immunized mice were injected intravenously or intracerebrally into naive mice that subsequently showed no neurological symptoms or loss of Purkinje cells. We conclude that the anti-Yo antibody, either in combination with or without complement or activated mononuclear cells, cannot be the sole cause of Purkinje cell loss.

Trial to establish an animal model of paraneoplastic cerebellar degeneration with anti-Yo antibody. 1. Mouse strains bearing different MHC molecules produce antibodies on immunization with recombinant Yo protein, but do not cause Purkinje cell loss

Passive transfer of anti-Yo antibody from patients with paraneoplastic cerebellar degeneration (PCD) associated with gynecological or breast carcinoma has not been successful in inducing an animal model. We used active immunization with recombinant Yo protein of four strains of mice bearing different MHC molecules: BALB/c (H-2d), C3H (H-2k), C57BL/6 (H-2b), SJL/J (H-2s). All the strains produced high anti-Yo antibody titer but none developed cerebellar ataxia or showed Purkinje cell loss. Spleen cells from the immunized mice also reacted with recombinant protein. Because C57BL/6(nu/nu) mice produce no anti-Yo antibody, mature helper T cells are required for its production. Results suggest that antibody production in peripheral blood alone is not sufficient for the development of PCD and that MHC class II molecules function in the activation of T cells to help B cells to help B cells produce antibodies.

Isoalloxazine ring of FAD is required for the formation of the core in the Hsp60-assisted folding of medium chain acyl-CoA dehydrogenase subunit into the assembly competent conformation in mitochondria

We studied the role of FAD in the intramitochondrial folding and assembly of medium-chain acyl-CoA dehydrogenase (MCAD), a homotetrameric mitochondrial enzyme containing a molecule of non-covalently bound FAD/monomer. In the MCAD molecule, FAD is buried in a crevice containing the active center. We have previously shown that upon import into mitochondria, newly processed MCAD is first incorporated into a high molecular weight (hMr) complex and that the hMr complex mainly consisted of MCAD-heat-shock protein 60 (hsp60) complex (Saijo, T., Welch, W.J., and Tanaka, K (1994) J. Biol. Chem. 269, 4401-4408). In the present study, we incubated in vitro synthesized precursor MCAD with mitochondria isolated from normal and riboflavin-deficient rat liver for 10-60 min and fractionated the solubilized mitochondria using gel filtration. The amount of MCAD in the hMr complex was larger and that of tetramer was smaller in riboflavin-deficient mitochondria than in control at any time point. In addition, riboflavin-deficient mitochondria were solubilized after 10-min import in a buffer containing ATP and were chased in the presence of FAD, FMN, or NAD+ or without any addition. The mitochondrial proteins were analyzed using gel filtration or immunoprecipitated with anti-hsp60 antibody. After 60-min chase in the presence of FAD, the majority of MCAD in the complex with hsp60 was transferred to tetramer, whereas no such transfer occurred after the chase in the absence of FAD. When chase was done in the presence of FMN, a significant amount of MCAD was transferred from the complex with hsp60 to tetramer, but the transfer was not as efficient as in the presence of FAD. The chase in the presence of NAD+ resulted in no transfer. These data suggest that isoalloxazine ring of FAD plays a critical role, exerting nucleating effect, in the hsp60-assisted folding of MCAD subunit into an assembly competent conformation, probably assisting the formation of the core.

Developmental changes of the 26 S proteasome in abdominal intersegmental muscles of Manduca sexta during programmed cell death

cDNA clone MS73 codes for an ATPase that is a regulatory subunit of the 26 S proteasome. Reverse transcriptase polymerase chain reaction analysis demonstrates that the expression of the gene dramatically increases in the pre-eclosion period. Western analyses show increases in other related. ATPases including MS73, MSS1, and mts2 but not TBP1. A similar increase in the 30-kDa subunit of the 20 S proteasome occurs. There are accompanying large changes in the peptidase activities of the 26 S proteasome. Relative to the 30-kDa subunit, there is no change in MSS1 and MS73, a 3-fold increase in mts2, and a 5-fold decline in TBP1. A large increase in the concentration of 26 S proteasomes together with extensive regulatory reprogramming may facilitate rapid muscular proteolysis.