Craniofacial Reconstruction Using Rational Cubic Ball Curves

This paper proposes the reconstruction of craniofacial fracture using rational cubic Ball curve. The idea of choosing Ball curve is based on its robustness of computing efficiency over Bezier curve. The main steps are conversion of Digital Imaging and Communications in Medicine (Dicom) images to binary images, boundary extraction and corner point detection, Ball curve fitting with genetic algorithm and final solution conversion to Dicom format. The last section illustrates a real case of craniofacial reconstruction using the proposed method which clearly indicates the applicability of this method. A Graphical User Interface (GUI) has also been developed for practical application.     

用杆状病毒为载体在昆虫细胞中表达马立克病病毒pp38基因

鸡马立克病病毒(MDV)38kd磷蛋白(pp38)基因中包括起始密码子和终止密码子的完整编码序列被整合进杆状病毒AcNPV的转移载体质粒pVL1392,用所得的含pp38基因的重组转移载体质粒pVLpp38I与野生型杆状病毒AcNPV的DNA共转染昆虫传代细胞系Sf9细胞后,用荧光抗体法以抗MDV单克隆抗体H_(19)筛选到能表达MDVpp38的重组杆状病毒克隆BP38 I。免疫印迹试验表明,在重组病毒BP38 I感染的Sf9细胞溶解物中,可表现一条分子量约为35—36kd的为单克隆抗体H_(19)识别的MDV特异性蛋白带。     

Application of RAPD technique to study polymorphism among Bacillus thuringiensis isolates from Jordan

The soil-borne bacterium Bacillus thuringiensis (Bt) is an important biological agent used against human and plant pests and diseases. Seven Jordanian Bt isolates, which have been analysed for toxicity against important pests, were also differentiated through serotyping. In this study, they were analysed at the molecular level using random amplified polymorphic DNA markers. Five more international strains were incorporated in the analysis. The DNA markers used showed high polymorphism among the isolates tested. However, the data did not align completely with earlier serotyping for most isolates. Therefore, it is recommended to engage several analyses (e.g. biochemical and molecular) when classifying newly surveyed Bt isolates in the world.     

Karyotype of maize (Zea mays L.) mitotic metaphase chromosomes as revealed by fluorescencein situ hybridization (FISH) with cytogenetic DNA markers

Here we demonstrate fluorescencein situ hybridization (FISH) of chromosome-specific cytogenetic DNA markers for chromosome identification in maize using repetitive and single copy probes. The fluorescently labeled probes, CentC and pZm4–21, were shown to be reliable cytogenetic markers in the maize inbred line KYS for identification of mitotic metaphase chromosomes. The fluorescent strength of CentC signal, relative position, knob presence, size and location were used for the karyotyping. Based on direct visual analysis of chromosome length and position of FISH signals, a metaphase karyotype was constructed for maize inbred line KYS. All chromosomes could be identified unambiguously. The knob positions in the karyotype agreed well with those derived from traditional cytological analyses except chromosomes 3, 4 and 8. One chromosome with a telomeric knob on the short arm was assigned to 3. A chromosome with a knob in the middle of the long arm was assigned number 4 by simultaneous hybridization with a knob-specific probe pZm4–21 and a chromosome 4-specific probe Cent 4. On chromosome 8, we found an additional small telomeric knob on the short arm. In addition, chromosome-specific probes were employed to identify chromosome 6 (45S rDNA) and chromosome 9 (single-copy probeumc105a cosmid).     

Yeast programmed cell death: an intricate puzzle

Yeasts as eukaryotic microorganisms with simple, well known and tractable genetics, have long been powerful model systems for studying complex biological phenomena such as the cell cycle or vesicle fusion. Until recently, yeast has been assumed as a cellular 'clean room' to study the interactions and the mechanisms of action of mammalian apoptotic regulators. However, the finding of an endogenous programmed cell death (PCD) process in yeast with an apoptotic phenotype has turned yeast into an 'unclean' but even more powerful model for apoptosis research. Yeast cells appear to possess an endogenous apoptotic machinery including its own regulators and pathway(s). Such machinery may not exactly recapitulate that of mammalian systems but it represents a simple and valuable model which will assist in the future understanding of the complex connections between apoptotic and non-apoptotic mammalian PCD pathways. Following this line of thought and in order to validate and make the most of this promising cell death model, researchers must undoubtedly address the following issues: what are the crucial yeast PCD regulators? How do they play together? What are the cell death pathways shared by yeast and mammalian PCD? Solving these questions is currently the most pressing challenge for yeast cell death researchers.     

Comparison between genetic and physical maps in Zea mays L. of molecular markers linked to resistance against Diatraea spp

In the pachytene stage, chromosomes are maximally extended and can easily be distinguished. Therefore, by applying fluorescence in situ hybridization (FISH) to pachytene chromosomes, it is possible to generate a high-resolution physical map of chromosome 9 in maize. Molecular markers ( umc105a on the short arm of chromosome 9, csu145a on the long arm) were used that flank quantitative trait loci (QTL) for sugarcane borer (SCB) and southwestern corn borer (SWCB) resistance. As reference markers, a centromere-specific probe (CentC) and a knob-specific probe (pZm4-21) were utilized. Two fluorescent dyes with four probes were used to physically position these markers. Signals of repetitive DNA sequences in cosmid probes were suppressed by chromosome in situ suppression (CISS) hybridization. FISH signals were strong and reproducible for all probes. We measured the distances in micrometers for four subchromosomal regions and estimated the corresponding number of base pairs. The physical locations of the markers were compared on mitotic metaphase and pachytene chromosomes to the genetic map of chromosome 9. Genetic analysis positioned the two markers for SCB resistance in a central interval representing approximately 33.7% of the genetic length. However, the physical distance between these probes was determined to encompass about 70% of the physical length of chromosome 9. The two markers were located at distal positions on opposite arms of chromosome 9. Physical maps provide valuable information for gene isolation and understanding recombination.