Seed characteristics and fatty acid composition of castor (<i>Ricinus communis</i> L.) varieties in Northeast China

Oil content and fatty acid composition were investigated on 12 castor varieties and strains by using the soxhlet extraction method and capillary gas chromatography. This was made to provide a reference and theoretical basis for castorbean breeding with high oil content, determine variability of seed compounds for breeding purposes, and broaden chemical material choices. Results revealed that crude fat percentage in seeds ranged from 18.91 to 35.84% with an average of 25.91%; the absolute content of ricinoleic acid varied between 171.65 g/kg and 314.03 g/kg with an average of 222.43 g/kg, and kernel crude fat percentage was between 24.28 and 46.97% with an average of 34.30%. All these study variables were highest in the 2129 strain. The percentage of ricinoleic acid in crude fat was between 83.85 to 87.62%, and the highest value was found in the zhebi4 accession. The other fatty acids appeared in small concentrations, and showed small amplitude: 1.12 to 1.61%, 1.21 to 1.61%, 3.53 to 4.80%, 5.35 to 6.38%, 0.52 to 0.79%, 0.05 to 0.08% and 0.43 to 0.55%, for palmitic, stearic, oleic, linolic, linolenic, arachidic, and arachidonic acids, respectively. One hundred seed weight was determined for each accession. One hundred seed weight ranged from 25.7 g to 34.0 g with an average of 29.9 g. There was a significant correlation between seed weight and oil content, but the correlation value was low (r=0.51). Cluster analysis by SSPS based on the content of fatty acid composition revealed that the accessions were divided into three independent clusters. These findings will clearly provide useful information for further research in breeding and utilization of castor oil.     

Identification,cloning and functional characterization of a novel dermonecrotic toxin (phospholipase D) from brown spider (Loxosceles intermedia) venom

Brown spider bites are associated with lesions including dermonecrosis, gravitational spreading and a massive inflammatory response, along with systemic problems that may include hematological disturbances and renal failure. The mechanisms by which the venom exerts its noxious effects are currently under investigation. It is known that the venom contains a major toxin (dermonecrotic toxin, biochemically a phospholipase D) that can experimentally induce dermonecrosis, inflammatory response, animal mortality and platelet aggregation. Herein, we describe cloning, heterologous expression, purification and functionality of a novel isoform of the 33 kDa dermonecrotic toxin. Circular dichroism analysis evidenced correct folding for the toxin. The recombinant toxin was recognized by whole venom serum antibodies and by a specific antibody to a previously described dermonecrotic toxin. The identified toxin was found to display phospholipase activity and dermonecrotic properties. Additionally, the toxin caused a massive inflammatory response in rabbit skin dermis, evoked platelet aggregation, increased vascular permeability, caused edema and death in mice. These characteristics in combination with functional studies for other dermonecrotic toxins illustrate that a family of dermonecrotic toxins exists, and includes a novel member with high activity that may be useful for future structural and functional studies.     

骨形成蛋白(BMP)-2/4，-5与IA型BMP受体在口腔正常上皮、良性病变及癌变中的表达分析

认识BMP及其受体与口腔正常上皮及其癌变的关系。有助于深入了解口腔上皮癌变的机理。本文用免疫组织化学方法对BMP-2/4,-5与BMPR-IA在口腔颊部粘膜正常上皮,良性病变和癌变中的表达进行观察和半定量分析。标本包括：9例正常上皮（normal buccal muosa,NB)。8例慢性炎症（nonspecific chronic inflammation,NCI),7例过度角化（hyperkeratosis,HK)。5例乳头状瘤（squamous cell papilloma,SCP)。29例鳞癌（squamous cell carcinoma,SCC)。10例癌旁上皮（epithelium immediately adjacent to carcinoma,EAC)以及6例硬腭粘膜上皮（normal mucosa of hard palate,NHP）。结果显示：BMP-2/4,-5与BMPR-IA在口腔粘膜的正常与良性病变上皮中有弱的和不均一的阳性表达,NB与NHP无明显差别,而除3例SCC外,其它SCC几乎均有程度不一的阳性表达,在EAC中的表达接近于SCC,二者明显高于正常与良性组,此外,转移在淋巴结中的癌细胞的BMP-2/4与BMP-5阳性程度略高于原发灶的癌细胞,本文认为;BMP-2/4,5与BMPR-IA可能参与调控口腔上皮的癌变。     

Fine needle aspiration biopsy for improving the diagnostic accuracy of cut needle biopsy of focal liver lesions

OBJECTIVE: To determine the value of fine needle aspiration biopsy (FNAB) in comparison to cut needle biopsy (CNB) for the diagnosis of malignancy of focal liver lesions. STUDY DESIGN: A retrospective analysis was conducted on 68 FNAB and 49 CNB procedures performed on 62 patients with focal liver lesions. RESULTS: Cytology permitted a diagnosis of the lesion in 78% of cases. When punctures with insufficient material were excluded (11), the diagnostic accuracy of FNAB was 93%. For the 49 patients who underwent both procedures, FNAB and CNB had the same diagnostic accuracy, 78%, when considered separately and of 88% when considered in combination. Sensitivity, specificity and positive predictive value were similar for the 2 techniques. The negative predictive value was 64% for FNAB and CNB used separately and reached 78% when the 2 techniques were combined. There were no complications during the execution of FNAB and CNB. CONCLUSION: FNAB is an effective and safe method for the diagnosis of focal hepatic lesions, with diagnostic accuracy similar to that of CNB. When the 2 techniques are combined, the accuracy of the diagnosis of malignancy of focal liver lesions increases.     

Immobilization of pectinmethylesterase from acerola (Malpighia glabra L.) in porous silica

The total and partially purified enzyme pectinmethylesterase from acerola fruit was covalently immobilized on porous silica particles. These efficiency values were 114% for the total PME and 351% for the partially purified PME. In both forms the immobilization resulted in compounds with high thermal stability.     

Crystallization and X-ray crystallographic studies of an inhibitor from rye (Secale cereale) active against Acanthoscelides obtectus and Zabrotes subfasciatus alpha-amylases

Crystals of a new inhibitor present in rye seeds active against alpha-amylases from crop pests Acanthoscelides obtectus and Zabrotes subfasciatus have been obtained. A native dataset was collected at 2.21 A resolution with 99.3% completeness at CPr beamline at LNLS. The crystals belong to the trigonal system, space group P3(1)21 with a=b=78.21 A, and c=59.61 A. The crystal calculated solvent content is compatible with one dimer per asymmetric unit.     

Immobilization of lipases and assay in continuous fixed bed reactor

Lipases are versatile enzymes regarding the range of reactions they catalyse and substrates on which they act. They are as well important as catalyst in organic synthesis. Their immobilization on appropriate supports confer them greater stability besides the possibility of operating in continuous reactors. In order to explore these abilities, the reactions involving hydrolysis of p-nitrophenyl acetate (PNPA) and transesterification of PNPA with n-butanol were chosen. Lipases from two different sources were assayed, namely: microbial (Candida rugosa, CRL, Sigma Type VII) and pancreatic (PPL, Sigma, Type II). Two immobilization methods were also used, namely: 1). adsorption, using as support the following silica derivatives (150-300 microm e 450micro): phenyl, epoxy, amino and without derivation, and 2). covalent binding, using glutaraldehyde as binding agent and silica amino as support. This later method led to better results. Hydrolytic activity was 6.1 U/g(support) for CRL and 0.97 U/g(support) for PPL, and of transesterification, 2,8 U/g(support) for CRL and 1,9 U/g(support) for PPL. Stability of the immobilized enzyme as a function of temperature was evaluated for CRL at 40 degrees C and 50 degrees C and for PPL at 32 degrees C and 40 degrees C. The assays were initially carried out batchwise, both for soluble and immobilized enzymes, aiming to the obtention of parameters for the continuous reactor. Lipases immobilized by covalent binding were used in the assays of operational stability in continuous reactors. For PPL in aqueous medium, at 32 degrees C, and CRL in organic medium at 40 degrees C, both operating continuously, no significant loss of activity was detected along the analysis period of 17 days. In the case of CRL in aqueous medium at 40 degrees C there was a loss of activity around 40% after 18 days. For PPL in organic medium at 40 degrees C the loss was 33% after 20 days. Comparing both sources with each other, very different results were obtained. Higher activity was found for CRL, both for hydrolysis and for transesterification reactions, with higher stability in organic medium. PPL showed lower activity as well as higher stability in aqueous medium. The immobilization method by covalent binding showed to be the most appropriate. Immobilized lipases are therefore relatively stable both in aqueous and organic medium.