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The synthesis of ammonia from atmospheric dinitrogen, nitrogen fixation, is one of the essential reactions for human beings. Because the current industrial nitrogen fixation depends on dihydrogen produced from fossil fuels as raw material, the development of a nitrogen fixation reaction that relies on the energy provided by renewable energy, such as visible light, is an important research goal from the viewpoint of sustainable chemistry. Herein, we establish an iridium- and molybdenum-catalysed process for synthesizing ammonia from dinitrogen under ambient reaction conditions and visible light irradiation. In this reaction system, iridium complexes and molybdenum triiodide complexes bearing N-heterocyclic carbene-based pincer ligands act as cooperative catalysts to activate 9,10-dihydroacridine and dinitrogen, respectively. The reaction of dinitrogen with 9,10-dihydroacridine is not thermodynamically favoured, and it only takes place under visible light irradiation. Therefore, the described reaction system is one that affords visible light energy-driven ammonia formation from dinitrogen catalytically., (© 2022. The Author(s).)

SignificanceStrigolactones (SLs) are a group of apocarotenoid hormones, which regulates shoot branching and other diverse developmental processes in plants. The major bioactive form(s) of SLs as endogenous hormones has not yet been clarified. Here, we identify an Arabidopsis methyltransferase, CLAMT, responsible for the conversion of an inactive precursor to a biologically active SL that can interact with the SL receptor in vitro. Reverse genetic analysis showed that this enzyme plays an essential role in inhibiting shoot branching. This mutant also contributed to specifying the SL-related metabolites that could move from root to shoot in grafting experiments. Our work has identified a key enzyme necessary for the production of the bioactive form(s) of SLs.

Detection of traversable areas is essential to navigation of autonomous personal mobility systems in unknown pedestrian environments. However, traffic rules may recommend or require driving in specified areas, such as sidewalks, in environments where roadways and sidewalks coexist. Therefore, it is necessary for such autonomous mobility systems to estimate the areas that are mechanically traversable and recommended by traffic rules and to navigate based on this estimation. In this paper, we propose a method for weakly-supervised recommended traversable area segmentation in environments with no edges using automatically labeled images based on paths selected by humans. This approach is based on the idea that a human-selected driving path more accurately reflects both mechanical traversability and human understanding of traffic rules and visual information. In addition, we propose a data augmentation method and a loss weighting method for detecting the appropriate recommended traversable area from a single human-selected path. Evaluation of the results showed that the proposed learning methods are effective for recommended traversable area detection and found that weakly-supervised semantic segmentation using human-selected path information is useful for recommended area detection in environments with no edges.

Recent studies have shown that high BAALC expression predicts an adverse prognosis and may define an important risk factor in acute myeloid leukemia patients with normal karyotype. We performed, using real-time quantitative reverse transcriptase polymerase chain reaction (RQ-PCR), the molecular analysis of BAALC gene as a possible minimal residual disease (MRD) marker in 45 patients with newly diagnosed acute leukemia. BAALC transcript levels in 32 patients with CD34 expressed in leukemic blasts were 2-3 logs higher than background levels, and the copy number was reduced in patients achieving hematological remission. Comparative monitoring of MRD by RQ-PCR for the Wilms' tumor gene 1(WT1) or specific translocation markers demonstrated that BAALC had similar kinetics as WT1, AML1/ETO and minor BCR/ABL, but not PML/RARA. Quantitation of BAALC gene expression made it possible to assess MRD in patients with CD34-positive acute leukemia. To our knowledge, this is the first report concerning the use of BAALC mRNA expression for MRD monitoring.

In this study, we present a case of mild PBC that had anti-p97/VCP. A 53-year-old woman had been suspected of having chronic liver disease since 1983. In 1998, she visited the clinic, complaining of struma and pruritus. Laboratory findings on the first visit showed elevated levels of alkaline phosphatase (ALP) 454 IU/l(110-360), gammaGTP 250IU/l(-45) and IgM 671mg/dl(35-220). A screening of anti-mitochondrial antibody test was positive at a 1:80 dilution. A liver biopsy specimen revealed PBC at Scheuer stage 1. Following a treatment of ursodeoxycolic acid (UDCA) 300mg/day for 6 months, AMA and IgM were reduced to 1:20 and 220mg/dl, respectively. However, she was found to have low titer of anti-p97/VCP antibodies, determined by immunoprecipitation of radiolabeled recombinant protein produced by in vitro translation and transcription of the full length p97 cDNA. She has continued to be clinically stable following administration of UDCA 300mg. A PBC patient with anti-p97/VCP antibody showed a milder clinical course, suggesting some beneficial role of this antibody.

We have reported previously that p95c, a novel 95-kDa cytosolic protein, was the target of autoantibodies in sera of patients with autoimmune hepatic diseases. We studied 30 sera that were shown previously to immunoprecipitate a 95 kDa protein from [(35)S]-methionine-labelled HeLa lysates and had a specific precipitin band in immunodiffusion. Thirteen sera were available to test the ability of p95c antibodies to inhibit nuclear envelope assembly in an in vitro assay in which confocal fluorescence microscopy was also used to identify the stages at which nuclear assembly was inhibited. The percentage inhibition of nuclear envelope assembly of the 13 sera ranged from 7% to 99% and nuclear envelope assembly and the swelling of nucleus was inhibited at several stages. The percentage inhibition of nuclear assembly was correlated with the titre of anti-p95c as determined by immunodiffusion. To confirm the identity of this autoantigen, we used a full-length cDNA of the p97/valosin-containing protein (VCP) to produce a radiolabelled recombinant protein that was then used in an immunoprecipitation (IP) assay. Our study demonstrated that 12 of the 13 (93%) human sera with antibodies to p95c immunoprecipitated recombinant p97/VCP. Because p95c and p97 have similar molecular masses and cell localization, and because the majority of sera bind recombinant p97/VCP and anti-p95c antibodies inhibit nuclear assembly, this is compelling evidence that p95c and p97/VCP are identical.

Background: The prevalence of antimitochondrial antibody (AMA) in humans and its relationship to the development of primary biliary cirrhosis (PBC) are not well known. We have estimated the frequency of AMA in the general population, and studied its association with PBC., Methods: We studies 1714 corporate workers (median age, 48 years; range, 30 to 59 years) who had an annual health check from 1998 to 1999 at Kawasaki Social Insurance Hospital in Japan. We used an indirect immunofluorescence method for screening serum AMA. We applied the prevalence of AMA-positive people in the study group to the general population in Japan. Then the inferred AMA-positive population was compared to the actual number of patients with PBC in statistics published by the Japanese Government., Results: AMA was detected in 11 of 1714 people (0.64%; 95% confidence interval, 0.26% to 1.02%). All these 11 sera reacted with 2-oxoacid-dehydrogenase complex by immunoblotting. Of these 11 individuals, none had subjective symptoms, all had normal serum bilirubin levels, and 6 had abnormal liver function test results. Using published statistics for the Japanese population, we inferred that there were approximately 336,472 AMA-positive people in Japan from age 30 to 59 years. The number of patients with symptomatic PBC recorded by the nationwide epidemiological survey of the Japanese Government was 2459. Thus, we inferred the rate of symptomatic PBC among AMA-positive persons to be about 0.73% (2459/336,472)., Conclusions: AMA is not a rare antibody in the general population, but few people develop recognizable PBC even if they have AMA.

Primary biliary cirrhosis (PBC) sera contain antibodies which recognize various nuclear envelope proteins of which antibody against gp210 has been proven to be diagnostic for disease. In contrast, the clinical significance of another nuclear envelope antibody, anti-p62 antibody has not been well investigated. In the present study, we have analyzed anti-nuclear envelope antibodies by indirect immunofluorescence and immunoblot using rat liver nuclear envelope proteins and wheat germ agglutinin-bound fraction. Test sera were obtained from 175 patients with PBC and from 120 controls. Anti-gp210, anti-lamina associated polypeptide 2, anti-lamin B receptor, and anti-p62 complex antibodies were detected with a frequency of 26% (46 of 175), 6% (11 of 175), 9% (16 of 175), and 13% (15 of 115), respectively. The confirmation of Scheuer's stage IV was made with a frequency of 27% (4 of 15) in PBC patients with anti-p62 complex antibody, in contrast to only 2% (2 of 100) in PBC patients without anti-p62 complex antibody. This difference was found to be statistically significant. The presence of anti-p62 complex antibody may be related with the progressive or advanced state of PBC.

We report here a patient with chronic active hepatitis who had no markers for hepatitis viruses and no hyper-gamma-globulinemia, but had high titers of antimitochondrial antibody. Serum levels of alkaline phosphatase were normal, and antinuclear antibody, antismooth muscle antibody, and antiliver kidney microsome antibody tested negative. The titers of antimitochondrial antibody exceeded 1:640, and the positivity for anti-M2 was ascertained by using both ELISA and immunoblot with beef-heart mitochondria and a recombinant pyruvate dehydrogenase E2 subunit as antigens. This patient responded to ursodeoxycholic acid (UDCA) therapy in the beginning, but her hepatitis flared up during UDCA therapy. In contrast, she responded completely to corticosteroid therapy. The clinical course and histological findings of this patient strongly suggest that this patient has autoimmune hepatitis.

Anti-mitochondrial antibody(AMA) has been reported to be detectable in approximately 85% of patients with primary biliary cirrhosis(PBC). Therefore, a test for AMA is acceptable to be essential for diagnosing PBC. However, the positive rate in Japanese general population has not yet been determined. We tested sera from 1,145 corporate workers who took an annual health check and evaluated the liver of AMA-positive subjects. An indirect immunofluorescence method was used for screening AMA. ELISA and immunoblotting method were used for detecting anti-M2 in AMA-positive cases. AMA was detected in 5 of 1,145(0.44%) corporate workers. AMA positive rate was higher in females than in males(0.91% and 0%, respectively) and the AMA-positive people are all females over age 40. All of the AMA-positive sera are also positive for Anti-M2. Liver biopsy was performed in two AMA-positive cases and the histology was compatible with PBC in both cases.

Detection of anti-nuclear antibodies (ANA) is essential for diagnosing autoimmune diseases including autoimmune liver diseases. An indirect immunofluorescence (IIF) method with a cell line (HEp-2) derived from human laryngeal carcinoma has been used as a standard substrate. Recently, an enzyme-linked immunosorbent assay (ELISA) using multiple solid-phase antigens has been developed. We assayed sera from 272 cases of chronic liver diseases, 91 cases of healthy subjects and studied clinical significance of ANA. The sensitivity of IIF method in detection of ANA (fluorescence-ANA: FANA) and that of ELISA (ELISA-ANA: EANA) were 19.2% and 17.3% in chronic hepatitis B (CH-B), 16.7% and 17.3% in chronic hepatitis C (CH-C), 84.2% and 50.9% in primary biliary cirrhosis (PBC), 100% and 85.7% in autoimmune hepatitis (AIH) and 15.4% and 18.7% in healthy subjects. The sensitivity of EANA was considerably lower than that of FANA in PBC and AIH, but the sensitivity was the same in CH-C, CH-B, and healthy subjects. Because the solid-phase target antigens do not include nuclear antigen components recognized only by patients with PBC or AIH, ELISA can not detect all the species of ANA. This accounts for the low sensitivity of EANA in PBC and AIH. In conclusion, the current EANA is useful for screening of ANA, but FANA should be performed when PBC or AIH is suspected.

Vpr, an accessory gene of human immunodeficiency virus, induces cell cycle abnormality by accumulating cells at the G2-M phase. We reported recently that Vpr caused both micronuclei formation and aneuploidy. Here, we show that Vpr also induced chromosome breaks and gene amplification. Expression of Vpr induced more than 10-fold increase of colonies resistant to N-(phosphonacetyl)-L-aspartate, an inhibitor of pyrimidine de novo synthesis. Fluorescence in situ hybridization analysis detected that 4 of 10 N-(phosphonacetyl)-L-aspartate resistant clones studied had intrachromosomal amplification of carbamyl-phosphate synthetase/aspartate transcarbamoylase/dihydroorotase gene. Another single clone had dicentrics. Data suggested that the Vpr-induced chromosome breaks leading to gene amplification, followed by bridge-breakage-fusion cycle, were one of the possible mechanisms of Vpr-induced genomic instability.

Abnormality of humoral and cellular immune functions and the association of autoimmune diseases are frequently observed in primary biliary cirrhosis (PBC). The prevalence of autoimmune diseases was studied in 97 Japanese patients with PBC. Sjögren's syndrome was diagnosed in 33 percent of these patients, arthritis in 22 percent, scleroderma in 11 percent, CREST syndrome in 4 percent, Raynaud's phenomenon in 8 percent, autoimmune thyroiditis in 3 percent, respectively. Fifty-five percent of the patients had at least one autoimmune disease and 19 percent had two or more such disorders. In this study, the prevalence of associated autoimmune diseases was somewhat low compared to that of European and American studies. Geographical variations, however, might exist in the prevalence of autoimmune associations, and the frequent occurrence of coexisting autoimmune diseases suggests an autoimmune pathogenesis in PBC.

Background: Hepatocellular carcinoma (HCC) commonly develops in patients with chronic hepatitis or cirrhosis of the liver caused by hepatitis-C-virus (HCV) infection. We prospectively studied whether irregular regeneration of hepatocytes is a risk factor for HCC in these patients., Methods: 242 patients were enrolled after liver biopsy and followed up by ultrasonographic scanning every 3 months. We examined age, sex, platelet count, the diagnosis of cirrhosis or chronic hepatitis, liver-cell dysplasia, and irregular regeneration. We classified irregular regeneration as slight or severe, based on histological expression of pleiomorphism, anisocytosis, bulging, and map-like distribution of hepatocytes., Findings: 37 of 63 patients with cirrhosis and 26 of 179 with chronic hepatitis were judged to have severe irregular regeneration. HCC was diagnosed in 33 of 63 patients with cirrhosis (29 had severe irregular regeneration) and 12 of 179 patients with chronic hepatitis (11 had severe irregular regeneration) during mean follow-up of 5.5 years (SD 4.1; range 1-16). Multivariate analysis with a proportional-hazards model showed severe irregular regeneration (relative risk 15.1 [95% CI 5.6-40.7], p<0.0001) and a diagnosis of cirrhosis (3.8 [1.7-8.2], p=0.0008) to be significant risk factors for HCC. Within the diagnostic categories, irregular regeneration was also significant (cirrhosis 6.8 [2.1-21.9], p=0.0014; chronic hepatitis 28.5 [2.9-276.4], p=0.0038)., Interpretation: We recommend that liver biopsy to look for irregular regeneration should be done in patients with HCV-related chronic liver diseases. Those with severe irregular regeneration should be followed up carefully.

Sera from patients with primary biliary cirrhosis recognize various cellular components, such as mitochondria, centromere, nuclear envelope, and multiple nuclear dot antigens. There also appears to be a novel antibody reacting with a particular protein in these sera. The presence of this antibody was investigated by double immunodiffusion using rat liver cytoplasmic antigens, by immunoprecipitation of [35S]-methionine labelled HeLa cell extracts, and by immunoblot using disrupted HeLa cell extracts. Test sera were obtained from 491 patients with various liver diseases. Nine of the 491 sera were found to react with a 95-kDa protein as determined by immunoprecipitation of [35S]-methionine labelled HeLa cell extracts and by double immunodiffusion using a rat liver microsomal preparation. However, these same nine sera showed no reaction in the immunoblot assay. On the basis of its molecular mass and its presence in the cytoplasmic fraction, this antigen was named p95 C. This anti-p95 C antibody was detected in six of 50 (12%) sera from patients with primary biliary cirrhosis, and in three of 31 (9.7%) sera from patients with autoimmune hepatitis, but not in any of the remaining 410 sera obtained from patients with other hepatic diseases. It is concluded that anti-p95 C antibody reacts primarily with the native form of the 95-kDa protein, and represents another possible analyte for diagnosing autoimmune liver diseases.

One variety of anti-mitochondrial antibody(AMA) is characteristically found in sera from patients with primary biliary cirrhosis(PBC). The major target antigens of this type of AMA are M2s. It is well known, however, that AMA-negative PBC also exists. An alternative disease concept, called autoimmune cholangiopathy, recently has been advocated. This new concept is defined by the following criteria: 1)the failure to detect AMA and anti-M2, 2)the detection of a diffuse type of anti-nuclear antibody and anti-smooth muscle antibody, 3)pathological findings compatible with PBC, and 4)the effectiveness of prednisolone. However, the difference between AMA-negative PBC and autoimmune cholangiopathy is controversial. Therefore, we analyzed antibodies to four major M2 proteins with Western blotting in 34 cases of immunofluorescent AMA-negative PBC. In 31(91.2%) of these 34 AMA-negative sera, antibodies to at least one of these four major M2 proteins was detected. In serum samples from 34 control patients with AMA-positive PBC, antibodies to at least one of these four proteins were detected in all cases. In addition, we studied the frequency of cases which satisfied the serological criteria of autoimmune cholangiopathy. In only one(0.7%) of 141 cases was the serological criteria met. We conclude that to clarify the serological differences between autoimmune cholangiopathy and AMA-negative PBC, the analysis of M2 proteins by Western blotting is essential.

Anti-centromere antibody (ACA) have been recognized in sera of patients with primary biliary cirrhosis (PBC) and CREST syndrome. The major reactive antigen of ACA have been identified as CENP-B (80kDa). Using an indirect immunofluorescence (IIF) method and ELISA method, we detected ACA and anti-CENP-B antibody in patients with PBC and various liver diseases and collagen diseases. We tested sera of 44 patients with PBC, 8 patients with autoimmune hepatitis (AIH), 51 patients with chronic hepatitis B (CH-B), 312 patients with chronic hepatitis C(CH-C), 12 patients with progressive systemic sclerosis (PSS), 10 patients with systemic lupus erythematosus (SLE), 10 patients with rheumatoid arthritis (RA), and 30 with healthy subjects (HS). ACA was detected by IIF technique, using HEp-2 cell and fluoro-CENTRO slides (MBL) as substrates. Anti-CENP-B antibody was detected by ELISA method using recombinant CENP-B (MBL) as the antigen. ACA was detected in sera of 12 (27%) patients with PBC, two (25%) patients with AIH, five (2%) patients with CH-C, nine (75%) patients with PSS, and one (10%) patients with RA. ACA was not detected in sera of patients with CH-B and SLE and in HS. The results of IIF test for ACA, using HEp -2 cells and fluoro-CENTRO slides, were completely agreed. Anti-CENP-B antibody was detected in 28(97%) out of 29 patients sera positive for ACA. The titers of ACA and anti-CENP-B antibody did not show a correlation (r = 0.24). Out of 12 sera, in which, the titers of anti-CENP-B antibody was over 400. Among them, eight were patients with PBC and four were PSS. Later, out of four patients with PSS, three (75%) were found to be positive for anti-mitochondrial antibody. Out of five patients, in which the titer of anti-CENP-B antibody showed over 800, all were patients with PBC. The titers of ACA have no relationship with PBC. However, the titers of anti-CENP-B antibody have closed relationship with PBC. The reason why the titers of ACA and anti-CENP-B antibody were not correlated is unknown. We consider anti-CENP-B antibody is a new marker of a subset of PBC, because almost all the patients were PBC when this antibody showed over 400.

We have recently observed reactivity of primary biliary cirrhosis (PBC) sera with several proteins bearing N-acetylglucosamine residues from rat liver nuclear envelopes. The aim of this study was to characterize the reactive antigens. Sera from 31 patients with PBC, 30 with rheumatoid arthritis (RA) and 30 with Sjögren's syndrome (SS) were examined. Rim-like immunofluorescence staining was observed in 15 of 31 (48%) sera from patients with PBC, in 1 of 30 with RA and in 1 of 30 with SS. Upon immunoblotting using preparations of whole rat liver nuclear envelopes and their Triton X 100-KCl extract as antigen sources, a 200 kDa protein band was observed in 9 of sera with PBC. Furthermore, upon immunoblotting using the wheat germ aggulutinin-bound fraction of rat liver envelope as antigen, 62, 60 and 54 kDa protein bands corresponding to components of the p62 complex in the nuclear pore complex (Kita et al. Biochem. 113, 377-382) were observed in 7, 5 and 6 samples respectively, of the 31 PBC sera. Our data suggest that PBC sera recognize not only the 210 kDa protein but also the p62 complex proteins.

The sensitivity of human myelogenous leukemia cells to 1-beta-D-arabinofuranosylcytosine (ara-C) during induction of differentiation was examined. Treatment with hemin greatly increased the sensitivity of erythroid leukemia cells to ara-C. The enhancement of ara-C sensitivity by hemin was not as remarkable in nonerythroid leukemia cells. Hemin altered the metabolism of ara-C in human erythroleukemia K562 cells by reducing ara-C deaminase activity, increasing intracellular accumulation of ara-C, and activating the nucleoside kinases. These alterations may be involved in the enhancing effect of hemin on sensitivity of ara-C. These results suggest that some inducers of differentiation potentiate the antileukemic effect of ara-C on human erythroleukemia cells.

We studied 10 male and 23 female patients with PBC to determine whether the clinical and histological features of this disease differed in male and female patients. There were no significant difference between men and women in age distribution and biochemical examinations. In female patients, autoimmune associated conditions such as sicca syndrome, Raynaud syndrome and arthritis were observed 22%, 13% and 36%, respectively. By contrast, no male patients developed those conditions. 80% of the male patients and 70% of the female patients belonged to asymptomatic PBC, and early histological stage, such as Scheuer's I and II were observed 90% of the male patients and 78% of the female patients, respectively. No male patients showed clinical or histological progression during follow-up period (median was 64 months). Nevertheless, not a few female patients showed progression including 3 cases who died during the follow-up period (median was 47 months). We concluded that male patients with PBC tend to have favorable prognosis comparing to female patients.