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1.
Procedures are deseribed for the efficient isolation of protoplasts from a variety of oil palm (Elaeis guineensis Jacq.) tissues. Various factors including donor source, composition of enzyme mixture and culture medium affected the yield and viability of the protoplasts Polyembryogenic cultures of oil palm were the most suitable starting material in terms of yield, viability and metabolic competence. Pectolyase Y-23 in association with cellulase and hemicellulase was required for the efficient release of protoplasts from the oil palm tissues. Limited cell division to form microcallus was observed at very low frequency (<0.01%) when glutathione and catalase were incorporated in the culture medium.Abbreviations 2,4-d dichlorophenoxyacetic acid - DTT dithiothreitol - MES 2[N-morpholino] ethanesulphonic acid - NAA 1-naphthalene acetic acid - PVP polyvinylpyrrolidone  相似文献   
2.
Mutations in the hyperparathyroidism type 2 (HRPT2/CDC73) gene and alterations in the parafibromin protein have been established in the majority of parathyroid carcinomas and in subsets of parathyroid adenomas. While it is known that CDC73-mutated parathyroid tumors display specific gene expression changes compared to CDC73 wild-type cases, the molecular cytogenetic profile in CDC73-mutated cases compared to unselected adenomas (with an expected very low frequency of CDC73 mutations) remains unknown. For this purpose, nine parathyroid tumors with established CDC73 gene inactivating mutations (three carcinomas, one atypical adenoma and five adenomas) were analyzed for copy number alterations and loss of heterozygosity using array-comparative genomic hybridization (a-CGH) and single nucleotide polymorphism (SNP) microarrays, respectively. Furthermore, CDC73 gene promoter methylation levels were assessed using bisulfite Pyrosequencing. The panel included seven tumors with single mutation and three with double mutations of the CDC73 gene. The carcinomas displayed copy number alterations in agreement with previous studies, whereas the CDC73-mutated adenomas did not display the same pattern of alterations at loci frequently deleted in unselected parathyroid tumors. Furthermore, gross losses of chromosomal material at 1p and 13 were significantly (p = 0.012) associated with parathyroid carcinomas as opposed to adenomas. Quantitative PCR-based copy number loss regarding CDC73 was observed in three adenomas, while all the carcinomas were diploid or showed copy number gain for CDC73 gene. Hypermethylation of the CDC73 gene promoter was not observed. Our data could suggest that CDC73-mutated parathyroid adenomas exhibit a partly unique cytogenetic profile in addition to that of carcinomas and unselected adenomas. Furthermore, CDC73-mutated carcinomas displayed losses at 1p and 13 which are not seen in CDC73-mutated adenomas, making these regions of interest for further studies regarding malignant properties in tumors from CDC73-mutated cases. However, due to the small sample size, validation of the results in a larger cohort is warranted.  相似文献   
3.
The decapod family Penaeidae comprises most of the economically important marine shrimp species. Its members are widespread throughout the world, with its highest species diversity centred in the Indo-West Pacific region. Despite this importance, their taxonomy, classification and phylogeny are not yet settled due in part to incongruence among hypotheses proposed from molecular versus morphological studies. In this study, using a thorough taxonomic sampling of especially the South-East Asian species, we aim to (a) utilize a reconstructed phylogeny to test the monophyly of the Penaeidae and its currently recognized genera and (b) explore its species diversity in South-East Asian waters. To infer the phylogeny, a combined gene data set (including 109 ingroup and six outgroup taxa) of mitochondrial genes, COI and 16S rRNA, and two nuclear genes, NaK and PEPCK, was utilized. To explore its diversity, another data set that included 371 COI gene sequences (231 newly generated and 140 retrieved from public sources) was compiled and subsequently analysed with two different tools (ABGD and bPTP) for species delimitation. Other than supporting the non-monophyly of the Penaeidae with the Sicyoniidae nested within the penaeid tribe Trachypenaeini, the genera Penaeus, Mierspenaeopsis and Parapenaeopsis were also revealed to be polyphyletic. Our species delimitation analysis inferred that 94 putative species actually existed within the 71 morphospecies reviewed, indicating an underestimated biodiversity in this family and the potential presence of new species within the following morphospecies: Kishinouyepenaeopsis cornuta, K. incisa, Mierspenaeopsis sculptilis, M hardwicki, Parapenaeopsis coromandelica and Penaeus monodon.  相似文献   
4.

Petroleum pollution is a major concern in Antarctica due to the persistent nature of its hydrocarbon components coupled with the region’s extreme environmental conditions, which means that bioremediation approaches are largely inapplicable at present. The current study assessed the ability of the psychrotolerant phenol-degrader, Rhodococcus sp. strain AQ5-07, to assimilate diesel fuel as the sole carbon source. Factors expected to influence the efficiency of diesel degradation, including the initial hydrocarbon concentration, nitrogen source concentration and type, temperature, pH and salinity were studied. Strain AQ5-07 displayed optimal cell growth and biodegradation activity at 1% v/v initial diesel concentration, 1 g/L NH4Cl concentration, pH 7 and 1% NaCl during one-factor-at-a-time (OFAT) analyses. Strain AQ5-07 was psychrotolerant based on its optimum growth temperature being near 20 °C. In conventionally optimised media, strain AQ5-07 showed total petroleum hydrocarbons (TPH) mineralisation of 75.83%. However, the optimised condition for TPH mineralisation predicted through statistical response surface methodology (RSM) enhanced the reduction to 90.39% within a 2 days incubation. Our preliminary data support strain AQ5-07 being a potential candidate for real-field soil bioremediation by specifically adopting sludge-phase bioreactor system in chronically cold environments such as Antarctica. The study also confirmed the utility of RSM in medium optimisation.

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5.
The current work planned to assess the protecting properties of nimbolide against doxorubicin (DOX)‐treated myocardial damage. Myocardial damage was produced with 2.5 mg/kg of DOX given on alternative days (14 days). Thiobarbituric acid reactive substances (TBARS) levels of a lipid peroxidative marker were elevated, whereas reduced body weight, heart weight, blood pressure indices and reduced levels of antioxidants like glutathione‐S‐transferase, superoxide dismutase, catalase, glutathione peroxidase, glutathione, and glutathione reductase were observed in the heart tissue of DOX‐treated animals. DOX‐treated animals showed augmented levels of cardiac markers likes monocyte chemotactic protein‐1, interferon‐gamma, aspartate transferase, creatine kinase, lactate dehydrogenase, creatine kinase‐muscle/brain, heart‐type fatty acid‐binding protein, glycogen phosphorylase isoenzyme BB, transforming growth factor‐β, brain natriuretic peptide, myoglobin, and cTnI in serum. Histopathological assessment confirmed the DOX‐induced cardiotoxicity. Furthermore, DOX‐induced rats showed augmented inflammatory mediators (nuclear factor‐κB [NF‐kB], tumor necrosis factor‐α [TNF‐α], and interleukin‐1β [IL‐1β]) and increased PI3K/Akt signaling proteins (PI3K, p‐Bad/Bad, caspase‐3, and p‐Akt), whereas decreased oxidative markers (HO‐1 and NQO‐1) and p‐PTEN were observed. Nimbolide‐supplemented rats showed reduced activity/levels of cardiac markers and TBARS levels in serum and heart tissue. Levels of enzymatic and nonenzymatic antioxidants were augmented in the heart tissue of nimbolide‐supplemented rats. Nimbolide influence decreased apoptosis, inflammation, and enhanced antioxidant markers through the modulation of p‐Bad/Bad, caspase‐3, PI3K, p‐Akt, TNF‐α, NF‐kB, IL‐1β, HO‐1, NQO‐1, and p‐PTEN markers. The histopathological explanations were observed to be in line with biochemical analysis. Therefore, the finding of current work was that nimbolide has a defensive effect on the myocardium against DOX‐induced cardiac tissue damage.  相似文献   
6.
Mycopathologia - Candida albicans has been reported globally as the most widespread pathogenic species contributing candidiasis from superficial to systemic infections in immunocompromised...  相似文献   
7.
Egyptian flower mantis Blepharopsis mendica (Order: Mantodea) is a widespread mantis species throughout the southwest Palearctic region. The ecological and geographical distribution of such interesting species is rarely known. So, through this work, habitat suitability models for its distribution through Egyptian territory were created using MaxEnt software from 90 occurrence records. One topographic (altitude) and eleven bioclimatic variables influencing the species distribution were selected to generate the models. The predicted distribution in Egypt was focused on the Delta, South Sinai, the north-eastern part of the country, and some areas in the west including Siwa Oasis. Temporal analysis between the two periods (1900–1961) and (1961–2017) show current reduction of this species distribution through Delta and its surrounding areas, may be due to urbanization. On the other hand, it increases in newly protected areas of South Sinai. Under the future climate change scenario, the MaxEnt model predicted the habitat gains for B. mendica in RCP 2.6 for 2070 and loss of habitat in RCP 8.5 for the same year. Our results can be used as a basis for conserving this species not only in Egypt, but also throughout the whole of its range, also, it show how the using of geo-information could help in studying animal ecology.  相似文献   
8.
The family Calliphoridae is a group of heterogenous calyptrate flies with a worldwide distribution including species of ecological, veterinary, medical, and forensic importance. Notorious for their parasitic habits, the larvae of many blowflies are characterised – like some other dipteran larvae – by their ability to develop in animal flesh. When parasitism affects a living host, it is termed “myiasis”. This has led the Calliphoridae to be considered as a pivotal family in its relationship with a man. Nevertheless, even after more than 50 years of research, the phylogenetic relationships among calliphorid subfamilies together with the evolutionary origin of myiasis remain unclear. In order to elucidate these problems, we constructed three phylogenetic trees by using nucleotide sequence data from cytochrome oxidase subunit one (COI), representing a mitochondrial conservative gene, and nuclear 28S subunit of ribosomal RNA gene (28S rRNA) in order to interpret the evolutionary profile of myiasis in the family Calliphoridae. The sequenced data represented species associated with ectoparasitic life-styles, either saprophagy or facultative and obligate parasitism. A total number of 50 accessions were collected for 28S rRNA, 56 for COI, and 38 for combined sequences phylogeny. Molecular Evolutionary Genetics Analysis (MEGA) software was used to align 2197 nucleotide positions of 28S rRNA and 1500 nucleotide positions of COI with a gap opening penalties and gap extension penalties equalling 20 and 0.1 respectively. The results reveal the non-monophyly of the family Calliphoridae despite the stable monophyletic status of the Chrysomyinae, Luciliinae, and Auchmeromyiinae. Also, our findings recommend ranking the Toxotarsinae as a separate family. Furthermore, comparative analysis of the phylogenetic trees shows that the habit of obligatory myiasis originated independently more than five times. This strengthens our hypothesis that the origin of eating fresh meat is a case of convergent evolution that has taken place after speciation events millions of years ago. Finally, estimating the divergence dates between lineages from molecular sequences provides a better chance of understanding their evolutionary biology.  相似文献   
9.
10.
Genus Rusa, belonging to the deer family Cervidae is native to the Indo-Malaya Archipelago (IMA). However, detailed information on the Rusa genus in the IMA is limited. This review provides comprehensive information on the Rusa genus in the IMA including, threats and conservation efforts. There are four species of deer in Rusa genus, which is Sambar deer (Rusa unicolor), Javan deer (Rusa timorensis), Visayan spotted deer (Rusa alfredi) and Philippine deer (Rusa marianna). Despite their wide distribution in the South Asian and Southeast Asian regions, they are under serious threats. Some conservation efforts that are being done to protect and conserve them among others are; (1) facilities protection, (2) habitat enrichment programme, (3) Ex-situ conservation, (4) legislations, and (5) captive breeding. Conservation through genetics is also an important step in conserving these species. Recommendations for conservation of the genus are also discussed; 1. maintenance of ecosystem. 2. more effective monitoring system on the existing protected area. 3. ex-situ conservation, and 4. habitat monitoring.  相似文献   
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