Induction of growth inhibition and differentiation of human leukemia HL-60 cells by a Tunisian gerboui olive leaf extract

Cancer protection associated with the consumption of olive products is well established, but not for leukemia. The protective effects of olive (Olea europaea L.) leaves were investigated by incubating human promyelocytic leukemia HL-60 cells with olive leaf extracts (OLEs) from seven principal Tunisian olive varieties, namely, Chemchali, Chemlali, Chétoui, Gerboui, Sayali, Zalmati and Zarrazi. The results showed significant growth inhibition of HL-60 cells incubated for 48 h with a 100-fold dilution of each OLE which had been obtained by incubating 10 g of dried leaves in 100 ml of 70% ethanol for one week with subsequent ultrafiltration. DNA fragmentation was observed in the cells incubated for 19 h with a 100-fold dilution of the Chemchali, Chemlali and Zalmati extracts. The results of a nitroblue tetrazolium (NBT) assay revealed NBT reduction, a differentiation marker, by the OLE-treated cells after an overnight incubation. The Gerboui extract showed the highest NBT reduction ability at more than 90%. An HPLC analysis revealed the presence of apigenin 7-glucoside in the extract, which was found in subsequent experiments to be responsible for the Gerboui extract-mediated cell differentiation.     

Growth rate and carrageenan analyses in four strains of <Emphasis Type="Italic">Kappaphycus alvarezii</Emphasis> (Rhodophyta,Gigartinales) farmed in the subtropical waters of São Paulo State,Brazil

Growth rate, semi-refined and refined carrageenan yields, 3,6-anhydrogalactose and sulphate contents, and gel strength were investigated in four strains of Kappaphycus alvarezii (brown, green and red tetrasporophytic strains, and one strain derived from tetraspores progeny, called G11) farmed in subtropical waters of São Paulo State, Brazil. All studied strains showed higher growth rates from February to May, decreasing from July to December. The G11 strain exhibited lower growth rates, but had semi-refined and refined carrageenan yields significantly higher than the others and similar to a commercial sample. A negative correlation between growth rate and semi-refined carrageenan yield was verified for all strains. The brown strain had the lowest content of 3,6-anhydrogalactose, while G11 and green strains showed higher values. No clear pattern of variation and no relationship were observed for sulphate and gel strength. However, all strains presented gel strength values near the one obtained from commercial sample. These results show that the carrageenan extracted from brown, green, red, and G11 strains of K. alvarezii cultured in subtropical waters of São Paulo State, Brazil with commercial potentials.     

A manually curated database of tetrapod mitochondrially encoded tRNA sequences and secondary structures

Background  

Mitochondrial tRNAs have been the subject of study for structural biologists interested in their secondary structure characteristics, evolutionary biologists have researched patterns of compensatory and structural evolution and medical studies have been directed towards understanding the basis of human disease. However, an up to date, manually curated database of mitochondrially encoded tRNAs from higher animals is currently not available.     

Recognition of functional genetic polymorphism using ESE motif definition: a conservative evolutionary approach to CYP2D6/CYP2C19 gene variants

Genetica - Although predicting the effects of variants near intron-exon boundaries is relatively straightforward, predicting the functional Exon Splicing Enhancers (ESEs) and the possible effects...     

印度藏茴香植物精油对温室棉蚜的熏蒸毒性及其成分分析（英文）

【目的】棉蚜Aphis gossypii是世界各地室内和室外果树、蔬菜和观赏植物上最具危害性的害虫之一。这一害虫取食植物汁液,产生蜜露,传播植物病毒,对植物从质和量上产生破坏。为了控制温室中的这一害虫,植物精油可用作化学农药的替代药物。本实验研究了印度藏茴香Carum copticum植物精油对棉蚜成虫的熏蒸毒性。【方法】将研磨的印度藏茴香干种子用改良的挥发油提取器(Clevenger-type apparatus)进行水蒸馏。所有生物测定均在27±2℃,相对湿度65%±5%和光周期16L∶8D条件下进行。研究采用完全随机设计,6个处理(5个不同浓度的精油加对照)。每一浓度3次重复,每一重复20头成虫。【结果】结果表明,棉蚜成蚜接触印度藏茴香精油24 h后出现明显的死亡。该精油对棉蚜成蚜的致死中浓度(LC50)为1.21μL/L空气。棉蚜成蚜的死亡百分率对精油的施用表现出较高的敏感性。精油浓度为1.21μL/L空气时,估计的棉蚜的致死中时(LT50)为11.79 h。这一精油的熏蒸毒性与浓度和接触时间之间具有一定的相关性。GC/MS组分分析结果表明,该精油由18种化合物组成,最重要的是一些化合物引起了熏蒸毒性,如麝香草酚(占50.07%)、γ-萜品烯(占23.99%)和对异丙基苯甲烷(占22.90%)。【结论】本研究结果表明印度藏茴香植物精油对棉蚜具有较好的杀虫效果。印度藏茴香精油对棉蚜产生较大的影响,由于它具有较高的熏蒸毒性潜力,因此可在温室中用于这一害虫的综合治理。     

Understanding the physiology of the asymptomatic diaphragm of the M1592V hyperkalemic periodic paralysis mouse

The diaphragm muscle of hyperkalemic periodic paralysis (HyperKPP) patients and of the M1592V HyperKPP mouse model rarely suffers from the myotonic and paralytic symptoms that occur in limb muscles. Enigmatically, HyperKPP diaphragm expresses the mutant NaV1.4 channel and, more importantly, has an abnormally high Na⁺ influx similar to that in extensor digitorum longus (EDL) and soleus, two hindlimb muscles suffering from the robust HyperKPP abnormalities. The objective was to uncover the physiological mechanisms that render HyperKPP diaphragm asymptomatic. A first mechanism involves efficient maintenance of resting membrane polarization in HyperKPP diaphragm at various extracellular K⁺ concentrations compared with larger membrane depolarizations in HyperKPP EDL and soleus. The improved resting membrane potential (EM) results from significantly increased Na⁺ K⁺ pump electrogenic activity, and not from an increased protein content. Action potential amplitude was greater in HyperKPP diaphragm than in HyperKPP soleus and EDL, providing a second mechanism for the asymptomatic behavior of the HyperKPP diaphragm. One suggested mechanism for the greater action potential amplitude is lower intracellular Na⁺ concentration because of greater Na⁺ K⁺ pump activity, allowing better Na⁺ current during the action potential depolarization phase. Finally, HyperKPP diaphragm had a greater capacity to generate force at depolarized EM compared with wild-type diaphragm. Action potential amplitude was not different between wild-type and HyperKPP diaphragm. There was also no evidence for an increased activity of the Na⁺–Ca²⁺ exchanger working in the reverse mode in the HyperKPP diaphragm compared with the wild-type diaphragm. So, a third mechanism remains to be elucidated to fully understand how HyperKPP diaphragm generates more force compared with wild type. Although the mechanism for the greater force at depolarized resting EM remains to be determined, this study provides support for the modulation of the Na⁺ K⁺ pump as a component of therapy to alleviate weakness in HyperKPP.     

In-vitro diagnosis of single and poly microbial species targeted for diabetic foot infection using e-nose technology

Background

Effective management of patients with diabetic foot infection is a crucial concern. A delay in prescribing appropriate antimicrobial agent can lead to amputation or life threatening complications. Thus, this electronic nose (e-nose) technique will provide a diagnostic tool that will allow for rapid and accurate identification of a pathogen.

Results

This study investigates the performance of e-nose technique performing direct measurement of static headspace with algorithm and data interpretations which was validated by Headspace SPME-GC-MS, to determine the causative bacteria responsible for diabetic foot infection. The study was proposed to complement the wound swabbing method for bacterial culture and to serve as a rapid screening tool for bacteria species identification. The investigation focused on both single and poly microbial subjected to different agar media cultures. A multi-class technique was applied including statistical approaches such as Support Vector Machine (SVM), K Nearest Neighbor (KNN), Linear Discriminant Analysis (LDA) as well as neural networks called Probability Neural Network (PNN). Most of classifiers successfully identified poly and single microbial species with up to 90% accuracy.

Conclusions

The results obtained from this study showed that the e-nose was able to identify and differentiate between poly and single microbial species comparable to the conventional clinical technique. It also indicates that even though poly and single bacterial species in different agar solution emit different headspace volatiles, they can still be discriminated and identified using multivariate techniques.     

Biodegradation pathway and detoxification of the diazo dye Reactive Black 5 by Phanerochaete chrysosporium

The in vivo biodegradation of the diazo dye Reactive Black 5 (RB5) by Phanerochaete chrysosporium immobilised on cubes of nylon sponge and on sunflower-seed shells (SS) in laboratory-scale bioreactors was investigated. The SS cultivation led to the best results with a decolouration percentage of 90.3% in 72 h for an initial RB5 concentration of 100 mg/L. It was found that the addition of 0.4 mM veratryl alcohol (VA) into the medium considerably increased the decolouration rate in SS cultivation. However, the addition of VA had no effect in the nylon cultivation. Thin layer chromatography (TLC) revealed that RB5 was transformed into one metabolite after 24 h. UV-vis spectroscopy and Fourier Transform Infrared (FT-IR) also confirmed the biodegradation of RB5. Toxicity of RB5 solutions before and after fungal treatment was assayed using Sinorhizobium meliloti as a sensitive soil microorganism. P. chrysosporium transformed the toxic dye RB5 into a non-toxic product.