水稻小穗轴维管系统网络结构探讨

对籼型、粳型或其不育系与保持系代表品种小穗解剖观察表明：水稻小穗轴维管系统网络由中央维管束和各分枝维管束复合而成。来自小穗柄的１条大的中央主束和几条边围维管束经数次分枝、联结,不断产生新的分枝维管束进入相应的结构。一般颖片中维管束１－２条,第一稃片中１－３条,第二稃片中１－４条,第二朵退化小花残余结构中０－３条,顶生可孕小花的外稃中５条,内稃中３条,浆片中各２条,雄蕊中各１条,雌蕊中３条,主束与支     

The effect of a complex of meditation exercises on the psychophysiological state of young men

Using a simple motor response, a complex sensorimotor response, and a tapping test, the effect of a complex of meditation exercises on the neuromuscular coordination in healthy male students who were preliminarily trained in methods of self-regulation based on meditation techniques was studied. As a result of a 6-min session of self-regulation, a considerable decrease (by 30% or more) in the time of a simple motor response and a complex sensorimotor response (due to a decrease in the latent time at constant motor time) and a simultaneous decrease in the number of errors, as well as a considerable increase in the result of the tapping test, were recorded. A short-term effect expressed in an increase in the rate and accuracy of sensorimotor responses can be a result of a change in the functional state of the nervous system under the impact of transcendental meditation techniques.     

Molecular cloning and expression of the col2a1a and col2a1b genes in the medaka, Oryzias latipes

The Col2a1 gene is expressed in notochord, otic vesicle, cartilaginous tissue and the anlage of endochondral bone during development in higher vertebrates. Type II collagen, a homotrimeric product of the Col2a1 gene, functions as a key regulatory protein for cartilage development and endochondral ossification. In medaka and zebrafish, a single homolog of the col2a1 gene has been identified. However, it is necessary to note that many genes are duplicated in teleost fishes. To clarify function of col2a1 genes in teleost fishes and to further understand the process of cartilage development and endochondral ossification, we cloned and mapped the gene loci of two col2a1 orthologs in medaka. The proteins encoded by both medaka col2a1a and col2a1b genes were highly conserved (85.3% and 82.6%) relative to human COL2A1, but synteny was not observed. We also examined the expression patterns of col2a1a and col2a1b during embryonic development. Whole-mount insitu hybridization data suggests that expression patterns of both medaka co2a1a and col2a1b genes are similar to that of zebrafish co2a1 in the early embryonic stages. In medaka, the two col2a1 genes show a closely correlated pattern of spatial and temporal expression. In late embryonic stages, however, there were differences in both expression patterns in the pectoral fin. This study is the first report of two homologs of col2a1 in teleosts and also the first examination of col2a1a and col2a1b expression patterns in this group.     

SELDI-TOF-MS Proteomic Profiling of Serum,Urine, and Amniotic Fluid in Neural Tube Defects

Neural tube defects (NTDs) are common birth defects, whose specific biomarkers are needed. The purpose of this pilot study is to determine whether protein profiling in NTD-mothers differ from normal controls using SELDI-TOF-MS. ProteinChip Biomarker System was used to evaluate 82 maternal serum samples, 78 urine samples and 76 amniotic fluid samples. The validity of classification tree was then challenged with a blind test set including another 20 NTD-mothers and 18 controls in serum samples, and another 19 NTD-mothers and 17 controls in urine samples, and another 20 NTD-mothers and 17 controls in amniotic fluid samples. Eight proteins detected in serum samples were up-regulated and four proteins were down-regulated in the NTD group. Four proteins detected in urine samples were up-regulated and one protein was down-regulated in the NTD group. Six proteins detected in amniotic fluid samples were up-regulated and one protein was down-regulated in the NTD group. The classification tree for serum samples separated NTDs from healthy individuals, achieving a sensitivity of 91% and a specificity of 97% in the training set, and achieving a sensitivity of 90% and a specificity of 97% and a positive predictive value of 95% in the test set. The classification tree for urine samples separated NTDs from controls, achieving a sensitivity of 95% and a specificity of 94% in the training set, and achieving a sensitivity of 89% and a specificity of 82% and a positive predictive value of 85% in the test set. The classification tree for amniotic fluid samples separated NTDs from controls, achieving a sensitivity of 93% and a specificity of 89% in the training set, and achieving a sensitivity of 90% and a specificity of 88% and a positive predictive value of 90% in the test set. These suggest that SELDI-TOF-MS is an additional method for NTDs pregnancies detection.     

Characterization and expression pattern of zebrafish Anti-Müllerian hormone (Amh) relative to sox9a, sox9b, and cyp19a1a, during gonad development

The role of Anti-Müllerian hormone (Amh) during gonad development has been studied extensively in mammals, but is less well understood in other vertebrates. In male mammalian embryos, Sox9 activates expression of Amh, which initiates the regression of the Mullerian ducts and inhibits the expression of aromatase (Cyp19a1), the enzyme that converts androgens to estrogens. To better understand shared features of vertebrate gonadogenesis, we cloned amh cDNA from zebrafish, characterized its genomic structure, mapped it, analyzed conserved syntenies, studied its expression pattern in embryos, larvae, juveniles, and adults, and compared it to the expression patterns of sox9a, sox9b and cyp19a1a. We found that the onset of amh expression occurred while gonads were still undifferentiated and sox9a and cyp19a1a were already expressed. In differentiated gonads of juveniles, amh showed a sexually dimorphic expression pattern. In 31 days post-fertilization juveniles, testes expressed amh and sox9a, but not cyp19a1a, while ovaries expressed cyp19a1a and sox9b, but not amh. In adult testes, amh and sox9a were expressed in presumptive Sertoli cells. In adult ovaries, amh and cyp19a1a were expressed in granulosa cells surrounding the oocytes, and sox9b was expressed in a complementary fashion in the ooplasm of oocytes. The observed expression patterns of amh, sox9a, sox9b, and cyp19a1a in zebrafish correspond to the patterns expected if their regulatory interactions have been conserved with mammals. The finding that zebrafish sox9b and sox8 were not co-expressed with amh in oocytes excludes the possibility that amh expression in zebrafish granulosa cells is directly regulated by either of these two genes.     

Parastrongylus (=Angiostrongylus) cantonensis now endemic in Louisiana wildlife

Parastrongylus (=Angiostrongylus) cantonensis, a lung worm of rats, was first reported in the United States in 1987, with a probable introduction by infected rats from ships docking in New Orleans, Louisiana, during the mid-1980s. Since then, it has been reported in nonhuman primates and a boy from New Orleans, and in a horse from Picayune, Mississippi, a distance of 87 km from New Orleans. Parastrongylus cantonensis infection is herein reported in a lemur (Varencia variegata rubra) from New Iberia, Louisiana, a distance of 222 km from New Orleans, and in a wood rat (Neotomafloridanus) and in 4 opossums (Didelphis virginiana) from Baton Rouge, Louisiana, a distance of 124 km from New Orleans. The potential of a great variety of gastropods serving as intermediate hosts in Louisiana may pose a threat to wildlife as well as to domesticated animals in the areas where infected Norway rats (Rattus norvegicus) are present.     

A characteristic Mls-1a response precedes Mls-1a anergy in vivo

T cells expressing V beta 6 variable gene segments of the T cell receptor undergo blast formation and divide in mice after injection of lymphoid cells bearing minor lymphocyte-stimulating (Mls)-1a gene products. This in vivo Mls-1a response resembles in vitro Mls-1a stimulation; it is dose dependent, not MHC-class II haplotype restricted, but requires expression of functional IE gene products. The in vivo Mls-1a response is followed by a complete and specific in vivo Mls-1a anergy and a partial in vitro Mls-1a anergy. The measurement of a Mls-1a response in vivo and of the establishment of in vivo anergy to it provides a convenient method to assay Mls-1a reactivity of T cells in vivo on a cell-by-cell basis in terms of cell surface phenotype, size, and mitotic activity.     

Cell type-specific localization of sphingosine kinase 1a in human tissues.

Cell type-specific localization of sphingosine kinase 1a (SPHK1a) in tissues was analyzed with a rabbit polyclonal antibody against the 16 C-terminal amino acids derived from the recently reported mouse cDNA sequence of SPHK1a. This antibody (anti-SPHK1a antibody) can react specifically with SPHK1a of mouse, rat, and human tissues. Utilizing its crossreactivity to human SPHK1a, the cell-specific localization of SPHK1a in human tissues was histochemically examined. Strong positive staining for SPHK1a was observed in the white matter in the cerebrum and cerebellum, the red nucleus and cerebral peduncle in the midbrain, the uriniferous tubules in the kidney, the endothelial cells in vessels of various organs, and in megakaryocytes and platelets. The lining cells of sinusoids in the liver and splenic cords in the spleen showed moderate staining. Columnar epithelia in the intestine and Leydig's cells in the testis showed weak staining patterns. In addition, TPA-treated HEL cells, a human leukemia cell line, showed a megakaryocytic phenotype accompanied with increases in immunostaining of both SPHK1a and SPHK enzyme activity, suggesting that SPHK1a may be a novel marker of megakaryocytic differentiation and that this antibody is also useful for in vitro study of differentiation models.(J Histochem Cytochem 49:845-855, 2001)     

Regulation of the sodium/sulfate co-transporter by farnesoid X receptor alpha

Fxralpha is known to regulate a variety of metabolic processes, including bile acid, cholesterol, and carbohydrate metabolism. In this study, we show direct evidence that Fxralpha is a key player in maintaining sulfate homeostasis. We identified and characterized the sodium/sulfate co-transporter (NaS-1; Slc13a1) as an Fxralpha target gene expressed in the kidney and intestine. Electromobility shift assays, chromatin immunoprecipitation, and promoter reporter studies identified a single functional Fxralpha response element in the second intron of the mouse Slc13a1 gene. Treatment of wild-type mice with GW4064, a synthetic Fxralpha agonist, induced Slc13a1 mRNA in the intestine and kidney. Slc13a1 mRNA was also induced in the kidney and intestine of wild-type, but not Fxralpha-/- mice, after treatment with the hepatotoxin alpha-naphthylisothiocyanate, which is known to result in elevated blood bile acid levels. Finally, we observed a decrease in Slc13a1 mRNA in the kidney and intestine of Fxralpha-/- mice and a corresponding increase in urinary excretion of free sulfates as compared with wild-type mice. These results demonstrate that mouse Slc13a1 is a novel Fxralpha target gene expressed in the kidney and intestine and that in the absence of Fxralpha, mice waste sulfate into the urine. Thus, Fxralpha is necessary for normal sulfate homeostasis in vivo.     

Wnt7a,frequently silenced by CpG methylation,inhibits tumor growth and metastasis via suppressing epithelial-mesenchymal transition in gastric cancer

Wnt7a is a member of the Wnt family and has been reported to be involved in the carcinogenesis and progression of many types of human cancer. However, little is known about Wnt7a expression and function in gastric cancer (GC). In the present study, Wnt7a expression in GC tissues and cells was investigated, the correlation between Wnt7a expression and the prognosis was also examined. The effects of Wnt7a on proliferation, invasion, and metastasis were evaluated in vitro and in vivo. Furthermore, the expression of epithelial-mesenchymal transition (EMT) markers and hypermethylation of the Wnt7a promoter were both detected. Wnt7a was downregulated in GC and its expression was associated with poor prognosis of patients with GC. Moreover, upregulation of Wnt7a significantly suppressed the growth, invasion, and metastasis abilities of GC cells in vitro and in vivo. Mechanistically, Wnt7a was found to inhibit EMT process of GC cells. In addition, the reducing expression of Wnt7a was due to methylation of 5′-CpG island within the promoter. Furthermore, the tumor suppressor role of Wnt7a is independent of canonical Wnt/β-catenin signaling in GC cells. In conclusion, our findings demonstrated that Wnt7a could be used as a potential diagnostic marker and target for GC management.     

Tumor-suppressive microRNA-10a inhibits cell proliferation and metastasis by targeting Tiam1 in esophageal squamous cell carcinoma

Aberrant microRNAs (miRNAs) expressions could contribute to the progression of numerous cancers, including esophageal squamous cell carcinoma, while miR-10a participates in multiple biological processes on cancers. However, the molecular mechanism of miR-10a in esophageal squamous cell carcinoma (ESCC) has not been investigated. Herein, miR-10a was significantly reduced in ESCC clinical tissues and ESCC cell lines (EC109 and TE-3). In addition, immunohistochemistry indicated that the expressions of α-SMA, Ki-67, and PCNA in tumor tissues were higher than that of controls. In vitro, overexpression of miR-10a dramatically suppressed cell proliferation and enhanced cell apoptosis, while the decrease of miR-10a expressed the opposite outcome. Specially, overexpression of miR-10a caused a G0/G1 peak accumulation. Moreover, miR-10a also negatively regulated ESCC cell migration and invasion. Furthermore, targetscan bioinformatics predictions and the dual-luciferase assay confirmed that Tiam1 was a direct target gene of miR-10a. The statistical analysis showed Tiam1 was negatively in correlation with miR-10a in ESCC patient samples. And silencing Tiam1 could lead to a decline on cell growth, invasion, and migration in ESCC cell lines, while it could enhance cell apoptosis and cause a G0/G1 peak accumulation. In vivo, it revealed that miR-10a notably decreased the tumor growth and metastasis in xenograft model and pulmonary metastasis model. And it showed a lower expressions of Tiam1 in the miR-10a mimics group by immunohistochemistry. Taken together the results, they indicated that miR-10a might function as a novel tumor suppressor in vitro and in vivo via targeting Tiam1, suggesting miR-10a to be a candidate biomarker for the ESCC therapy.     

Studies of the chemical composition of a healing skin wound in rats, and of the concentrations of some constituents of tissues distant from the healing wound

1. A skin lesion was made in rats by dorsal incision and the insertion of a polythene tube. 2. Over a period of 25 days after wounding, assays were performed for ascorbic acid, DNA, hydroxyproline, methionine, tryptophan, tyrosine and free amino acids in the lesion tissue. 3. The neutral-salt-soluble proteins of the lesion tissue were fractionated on DEAE-Sephadex, with the separation of fibrinogen and γ-globulin from a serum protein fraction. 4. Over a period of 20 days after wounding, in wounded rats and in controls, assays were conducted for: ascorbic acid in lens and liver, hydroxyproline, soluble protein, methionine and water in muscle and tendon, and free amino acids in muscle. 5. Relative to controls there was a decrease in lens and liver ascorbic acid, a rise in tendon hydroxyproline, a rise in muscle free amino acids, a fall in muscle protein and a rise in tendon and muscle water.     

Pathogenicity of two species of Fusarium on some cultivars of bean in greenhouse

Twenty isolates of Fusarium oxysporum and F. solani were isolated from the infected roots of bean in different farms of east Azarbaijan and Tehran Provinces and their pathogenicity determined. Most isolates of the fungi were identified as F. oxysporun. They caused root rot, yellowing and wilting of bean in the field. In this test, the roots of 6 cultivars of bean seedlings soaked in suspension of the 7 isolates of the fungi (a1, Gogan, a2, Bilverdi, a3, Savojbolagh-Hashtgerd, a4, field of Agr. Coll. a5, Khomein, a6, Ramjin of F. oxysporum and a7 of F. solani of Varamin, Iran) for 5 minute (106 spores/ml.) then transplanted into the sterilized soil in 4 pots (as replication). For control (a8) the roots soaked in distilled water. The results showed that percentage average of necrotic roots and crowns of isolates al, a2, a3, a5, a6, a7 was %20.31 in group a, a4 was %43.52 in group b and a8 was %2.77 in group c after 3 weeks. The isolate a4 (from the field of Agricultural College, Karaj) was more infectious than the other because it caused wilting, yellowing the leaves and decreased the growth very soon, followed by a5 with %25.32 rate was more pathogenic. Bean cultivar Goli-Red was more tolerant with %10.02 than the others of 16.29 (Naz Red) to 25.15 percent of necrotic the roots & stems.     

MiR-34a inhibits the proliferation,migration, and invasion of oral squamous cell carcinoma by directly targeting SATB2

In various kinds of carcinomas, the special AT-rich sequence-binding protein 2 (SATB2) with its atypical expression promotes the metastasis and progression of the tumor, though in the oral squamous cell carcinoma (OSCC) its inherent mechanism and the status of SATB2 remain unclear. The role played by the SATB2 expression in the OSCC cell lines and tissue samples in the target of miR-34a downstream is the intended endeavor of this study. In te OSCCs the miR-34a expression was determined by quantitative real-time polymerase chain reaction (q-PCR), while the SATB2 expression in the cell lines and tissue samples in OSCC was analyzed with the q-PCR and the western blot. Studies in both in vitro and in vivo of the effects of miR-34a on the initiation of OSCC were conducted. As a direct target of the miR-34a the SATB2 was verified with the luciferase reporter assay. In cases where the miR-34a levels were low, the SATB2 in OSCCs seemed to be overexpressed. Besides, both in the in vitro and in vivo a suppression of migration, invasion, and cell growth was caused by miR-34a by down regulating the SATB2 expression. The SATB2 being a direct target of miR-34a was confirmed by the cotransfection of miR-34a mimics specifically the decrease in the expression of luciferase of SATB2–3′UTR-wt reporter. As a whole, our study confirmed the inhibition of miR-34a in the invasion, proliferation, and migration of the OSCCs, playing a potential tumor suppressor role with SATB2 as its downstream target.     

eIF3a与肿瘤发生、演进和干预的研究进展

真核翻译起始因子3(Eukaryotic translation factor 3,eIF3)是由多个亚单位组成的复合因子,其中eIF3a是其最大的亚单位。很多研究表明在酵母和哺乳动物细胞中,eIF3都参与了m RNA翻译起始,并对蛋白质的合成有很好的调控作用。值得一提的是eIF3a通过调控一系列与肿瘤的生成、细胞周期的调控DNA修复等过程相关的m RNA的翻译从而在肿瘤的发生、演进和干预中发挥重要作用。此外,研究发现eIF3a对RAF-MEK-ERK信号通路有抑制作用。eIF3a对蛋白质翻译的调节及其对RAF-MEK-ERK信号通路的影响使其有望成为肿瘤治疗的新靶点。本文将着重围绕eIF3a在肿瘤发生、演进和干预中的作用进行概述。     

Influence of prior and visual information on eye movements in amblyopic children

This study analyzed the characteristics of pursuit and assessed the influence of prior and visual information on eye velocity and saccades in amblyopic and control children, in comparison to adults. Eye movements of 41 children (21 amblyopes and 20 controls) were compared to eye movements of 55 adults (18 amblyopes and 37 controls). Participants were asked to pursue a target moving at a constant velocity. The target was either a ‘standard’ target, with a uniform color intensity, or a ‘noisy’ target, with blurry edges, to mimic the blurriness of an amblyopic eye. Analysis of pursuit patterns showed that the onset was delayed, and the gain was decreased in control children with a noisy target in comparison to amblyopic or control children with a standard target. Furthermore, a significant effect of prior and visual information on pursuit velocity and saccades was found across all participants. Moreover, the modulation of the effect of visual information on the pursuit velocity by group, that is amblyopes or controls with a standard target, and controls with a noisy target, was more limited in children. In other words, the effect of visual information was higher in control adults with a standard target compared to control children with the same target. However, in the case of a blurry target, either in control participants with a noisy target or in amblyopic participants with a standard target, the effect of visual information was larger in children.