Role of GSL8 in low calcium tolerance in Arabidopsis thaliana.

Calcium (Ca) deficiency affects the yields and quality of agricultural products. Susceptibility to Ca deficiency varies among crops and cultivars; however, its genetic basis remains largely unknown. Genes required for low Ca tolerance in Arabidopsis thaliana have been identified. In this study, we identified a novel gene required for low Ca tolerance in A. thaliana. We isolated a mutant sensitive to low Ca concentrations and identified Glucan synthase-like (GSL) 8 as a gene responsible for low Ca tolerance. GSL8 is a paralog of the previously identified low Ca tolerance gene GSL10, which encodes ß-1,3 glucan(callose) synthase. Under low Ca conditions, the shoot growth of gsl8 mutants were inhibited compared to wild-type plants. A grafting experiment indicated that the shoot, but not root, genotype was important for the shoot growth phenotype. The ectopic accumulation of callose under low Ca conditions was reduced in gsl8 mutants. We further investigated the interaction between GSL8 and GSL10 by testing the gsl8 gsl10 double mutant for sensitivity to low Ca concentrations. The double mutant exhibited a more severe phenotype than the single mutant under 0.3 mM Ca, indicating additive effects of GSL8 and GSL10 with respect to low Ca tolerance. These results establish that GSL genes are required for low Ca tolerance in A. thaliana.

Arabidopsis Glucan Synthase-Like1 (GSL1) Is Required for Tolerance to Low-Calcium Conditions and Exhibits a Function Comparable to GSL10.

Crops that exhibit symptoms of calcium (Ca) deficiency constitute a major agricultural problem. Molecular breeding of resistant cultivars is a promising method for overcoming this problem. However, the involved genes must first be identified. Here, we show that the glucan synthase-like (GSL) 1 gene is essential for low-Ca tolerance in Arabidopsis thaliana. GSL1 is homologous to GSL10, which we previously showed was essential for low-Ca tolerance. Under low-Ca conditions, gsl1 mutants exhibit reduced growth and the onset of necrosis in new leaves. These symptoms are typical of Ca-deficient crops. A grafting experiment suggested that the shoot genotype, but not the root genotype, was important for the suppression of shoot necrosis. The ectopic accumulation of callose under low-Ca conditions was significantly reduced in gsl1 mutants compared with wild-type plants. Because the corresponding single-mutant phenotypes are similar, we investigated the interaction between GSL1 and GSL10 by testing the gsl1 gsl10 double mutant for sensitivity to low-Ca conditions. The double mutant exhibited a more severe phenotype than did the single mutants, indicating that the effects of GSL1 and GSL10 on low-Ca tolerance are additive. Because GSL genes are highly conserved within the plant kingdom, the GSL loci may be useful for breeding low-Ca tolerant crops.

Callose Synthesis Suppresses Cell Death Induced by Low-Calcium Conditions in Leaves.

Despite the importance of preventing calcium (Ca) deficiency disorders in agriculture, knowledge of the molecular mechanisms underlying plant adaptations to low-Ca conditions is limited. In this study, we provide evidence for a crucial involvement of callose synthesis in the survival of Arabidopsis (Arabidopsis thaliana) under low-Ca conditions. A mutant sensitive to low-Ca conditions, low calcium sensitive3 (lcs3), exhibited high levels of cell death in emerging leaves and had defects in its expanding true leaves under low-Ca conditions. Further analyses showed that the causal mutation was located in a putative ß-1,3-glucan (callose) synthase gene, GLUCAN SYNTHASE-LIKE10 (GSL10). Yeast complementation assay results showed that GSL10 encodes a functional callose synthase. Ectopic callose significantly accumulated in wild-type plants under low-Ca conditions, but at a low level in lcs3 The low-Ca sensitivity of lcs3 was phenocopied by the application of callose synthase inhibitors in wild-type plants, which resulted in leaf expansion failure, cell death, and reduced ectopic callose levels under low-Ca conditions. Transcriptome analyses showed that the expression of genes related to cell wall and defense responses was altered in both wild-type plants under low-Ca conditions and in lcs3 under normal-Ca conditions, suggesting that GSL10 is required for the alleviation of both cell wall damage and defense responses caused by low Ca levels. These results suggest that callose synthesis is essential for the prevention of cell death under low-Ca conditions and plays a key role in plants' survival strategies under low-Ca conditions.

Copper treatment of peach leaves causes lesion formation similar to the biotic stress response.

Peach (Prunus persica (L.) Batsch) leaves are sensitive to copper (Cu) exposure. The symptoms of Cu exposure are similar to those of bacterial spot disease; however, the mechanism underlying lesion formation caused by Cu exposure is not clear. Here, we investigated whether lesion formation caused by Cu exposure was related to the mechanism underlying plant resistance to microbial pathogens. When Cu was applied to the centre of a pinhole on peach leaves, a two-step process was observed. A pale green section in the shape of a doughnut, located far from a Cu treatment point, first appeared on a leaf treated with 2 mM CuSO4. Next, a yellow-white section gradually spread from the Cu treatment point to the pale green section. Finally, a gap was formed in the middle of the pale green section. The inner part of the pale green section contained 96% of the Cu applied, indicating that Cu is retained in the lesion area. Real-time PCR analysis of the expression of genes encoding pathogenesis-related proteins and enzymes involved in phytoalexin synthesis revealed that three genes (encoding chitinase, pathogenesis-related protein 4, and ß-1,3-glucanase-3) of the eight tested were upregulated by Cu treatment. Furthermore, treatment with caspase-1 inhibitors reduced lesion formation. These results show that Cu treatment of peach leaves causes cell death similar to that occurring during the biotic stress response.

Three cases of collagenous fibroma with rim enhancement on postcontrast T1-weighted images with fat suppression.

Collagenous fibroma, also known as desmoplastic fibroblastoma, is a benign fibrous soft tissue tumor showing gradual growth, commonly without aggressive local infiltration. Today, preoperative radiological diagnosis is important to avoid over-treatment and unnecessary extensive procedures, but is difficult because diagnostic imaging findings for collagenous fibroma have not been established. We report MR imaging findings of three collagenous fibromas in correlation with their histopathology. The characteristic rim enhancement on post-contrast T1-weighted images with fat suppression was present in all three cases, and we consider this to represent the difference in vascularity between the outer capsule-like fibrous tissue and the inside of the tumor.

Amplification-free whole-genome bisulfite sequencing by post-bisulfite adaptor tagging.

DNA methylation plays a key role in epigenetic regulation of eukaryotic genomes. Hence the genome-wide distribution of 5-methylcytosine, or the methylome, has been attracting intense attention. In recent years, whole-genome bisulfite sequencing (WGBS) has enabled methylome analysis at single-base resolution. However, WGBS typically requires microgram quantities of DNA as well as global PCR amplification, thereby precluding its application to samples of limited amounts. This is presumably because bisulfite treatment of adaptor-tagged templates, which is inherent to current WGBS methods, leads to substantial DNA fragmentation. To circumvent the bisulfite-induced loss of intact sequencing templates, we conceived an alternative method termed Post-Bisulfite Adaptor Tagging (PBAT) wherein bisulfite treatment precedes adaptor tagging by two rounds of random primer extension. The PBAT method can generate a substantial number of unamplified reads from as little as subnanogram quantities of DNA. It requires only 100 ng of DNA for amplification-free WGBS of mammalian genomes. Thus, the PBAT method will enable various novel applications that would not otherwise be possible, thereby contributing to the rapidly growing field of epigenomics.

Squamous cell carcinoma of the hilar lymph node with unknown primary tumor: a case report.

We herein report a rare case of squamous cell carcinoma (SCC) located in the hilar nodes with unknown primary tumor. A 56-year-old man underwent a thoracotomy under the clinical diagnosis of lung cancer with hilar nodes involvement. The tumor was found at the hilus and resected without pulmonary resection. The pathological diagnosis of this tumor was metastatic SCC in hilar lymph nodes. Examinations of the whole body failed to detect a primary site of the SCC. The patient is doing well with no clinical sign of recurrence 32 months after surgery.

Malignant peripheral nerve sheath tumor with Horner's syndrome: a case report.

We report on a 42-year-old woman with malignant peripheral nerve sheath tumor (MPNST) arising from the cervical sympathetic nerve. A collar incision and partial sternotomy were performed at the second intercostal space. The mass was spindle shaped and connected to the sympathetic trunk on the cranial and caudal sides, and it compressed the left carotid sheath on the median side. After the patient's uneventful recovery from surgery, adjuvant radiotherapy was administered to the area of resection. The patient remains well 5 years after surgery with no evidence of recurrence.

Long-distance signaling of iron deficiency in plants.

In a recent issue of the Planta, we established two points regarding the long-distance signal of iron status in tobacco (Nicotiana tabacum L.). One is that the long-distance signal generated in iron deficient tissues is a major factor in positively regulating the expressions of iron uptake genes in tobacco. The expression of a ferric chelate reductase gene (NtFRO1) and an iron-regulated transporter gene (NtIRT1) in roots decreased by cutting off the leaves grown under the iron-deficient condition. Conversely, the leaf-excision did not cause upregulation of the genes under the iron-sufficient condition. These results indicated that signals sent from shoots regulate iron uptake in roots under the iron-deficient condition. The second point regarding the long-distance signals is that the strength of the long-distance signals depends on the size of plant including roots. Both genes expressed in proportion to the weight of the remaining leaves, until a certain threshold. The gene expressions were observed also in hairy roots cultured under the iron deficient condition. In this paper, we discuss the long-distance signals of iron status in plants, using a newly obtained data.

Long-distance signals positively regulate the expression of iron uptake genes in tobacco roots.

Long-distance signals generated in shoots are thought to be associated with the regulation of iron uptake from roots; however, the signaling mechanism is still unknown. To elucidate whether the signal regulates iron uptake genes in roots positively or negatively, we analyzed the expressions of two representative iron uptake genes: NtIRT1 and NtFRO1 in tobacco (Nicotiana tabacum L.) roots, after shoots were manipulated in vitro. When iron-deficient leaves were treated with Fe(II)-EDTA, the expressions of both genes were significantly reduced; nevertheless iron concentration in the roots maintained a similar level to that in roots grown under iron-deficient conditions. Next, all leaves from tobacco plants grown under the iron-deficient condition were excised. The expression of two genes were quickly reduced below half within 2 h after the leaf excision and gradually disappeared by the end of a 24-h period. The NtIRT1 expression was compared among the plants whose leaves were cut off in various patterns. The expression increased in proportion to the dry weight of iron-deficient leaves, although no relation was observed between the gene expression and the position of excised leaves. Interestingly, the NtIRT1 expression in hairy roots increased under the iron-deficient condition, suggesting that roots also have the signaling mechanism of iron status as well as shoots. Taken together, these results indicate that the long-distance signal generated in iron-deficient tissues including roots is a major factor in positive regulation of the expression of NtIRT1 and NtFRO1 in roots, and that the strength of the signal depends on the size of plants.

Preoperative serum C-reactive protein level in non-small cell lung cancer.

UNLABELLED: We evaluated the significance of the preoperative serum C-reactive protein (CRP) level as a prognostic indicator in patients with non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Two hundred and three patients who had undergone a curative resection of NSCLC were retrospectively reviewed. RESULTS: The proportion of the tumor size over 3 cm per patient in the CRP-positive group (> or =0.5 mg/dL: n=38) was significantly higher than that in the CRP-negative group (<0.5 mg/dL: n = 165). The proportion of the adenocarcinoma in CRP-positive group was significantly lower than that in CRP-negative group. The overall and disease specific survival rates in the CRP-positive group were significantly lower than the rates in the CRP-negative group. Based on a multivariate analysis, the preoperative serum CRP level was selected as one of the unfavorable indicators regarding survival. CONCLUSION: The preoperative serum CRP level is an independent and significant indicator predictive of a poor prognosis in patients with NSCLC.

Preoperative peripheral naïve / memory ratio and prognosis of nonsmall-cell lung cancer patients.

PURPOSE: This study focused on the relationship between preoperative peripheral blood CD4(+) naïve/memory ratio and prognosis following surgery for patients with nonsmall-cell lung cancer. METHODS: After measuring CD3, CD4, CD8, CD45RA, CD45RO, CD25, and intracellular CTLA4 levels, CD4(+) naïve/memory ratios were determined for 13 controls and 38 patients. RESULTS: Although we observed no significant difference in the ratios, the patients exhibited a wider range of values than the controls. Of the 38 patients, 24 subsequently underwent surgery and were divided into three groups based on their preoperative CD4(+) naïve/memory ratio: Group I: <0.3; Group II: 0.3-0.8; and Group III: >0.8. Survival times were then evaluated. Group II survival was significantly better than Groups I and III. CONCLUSION: Our data suggest that the preoperative CD4(+) naïve/memory ratio may serve as a prognostic factor for nonsmall-cell lung cancer patients.

Popliteal artery pseudoaneurysm caused by osteochondroma.

A 49-year-old man with asymptomatic osteochondroma was found to have a pseudoaneurysm of the left popliteal artery. An angiography showed a popliteal artery pseudoaneurysm adjacent to a femoral osteochondroma. The osteochondroma was excised and the popliteal artery containing the tear was also excised by end-to-end anastomosis. Vascular complication of osteochondroma is extremely rare. Paul reported the first case of a popliteal artery pseudoaneurysm due to osteochondroma in 1953. A computerized literature search revealed 40 additional cases reported in English, providing sufficient detail to allow comparison. The average age of the patients was 22.6 years (range 9-51) and most cases identified involved males (30 of 41, 73%). Most pseudoaneurysm were located in the popliteal artery. This report discusses the authors' experience with this disorder and a review of the literature in English.