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51.
Myzus persicae (M. persicae) is now considered a threat to agricultural crops due to economic losses. Numerous synthetic insecticides applied every year against M. persicae, are reported to be unsafe for environment, humans, and beneficial insects. Furthermore, several species of Myzus have been found to develop resistance due to over application of these insecticides. Therefore, it is required to find some novel insecticide that would be safe for the environment as well as for humans. In the current study, two major pure constituents α-pinene and β-caryophyllene were evaluated for their insecticidal potential against M. persicae using a fumigant toxicity assay. Furthermore, impact of α-pinene and β-caryophyllene on expression of five different genes, e.g., HSP 60, FPPS I, OSD, TOL and ANT responsible for reproduction, dispersion, and growth of M. persicae has also been investigated. To perform fumigant toxicity assay, five different concentrations (3.5, 4, 4.5, 5 and 6 μL L−1) of α-pinene and β-caryophyllene were prepared. Lethal concentration (LC) was calculated, and gene expression studies were executed through qRT PCR at LC30 of α-pinene and β-caryophyllene. Both constituents demonstrated excellent fumigant toxicity effects against M. persicae at all five concentrations. However, α-pinene shows significantly better results (98%) as compared to β-caryophyllene (80%) after 72 h at 6 μL L−1 of dose. The highest upregulation in expression was demonstrated at LC30 dose of α-pinene in five in three out of five genes understudy (TOL, ANT, and FPPS I). Conversely, two genes HSP 60 and OSD demonstrated downregulation at LC30 dose of β-caryophyllene. Conclusively, our results highlighted the promising insecticidal potential of both compounds α-pinene and β-caryophylleneby interfering with the reproduction and development related processes in M. persicae, allowing us to recommend the phytoconstituents under investigation as an ecofriendly alternative to synthetic insecticides.  相似文献   
52.
Abiotic stresses are among the major limiting factors for plant growth and crop productivity. Among these, salinity is one of the major risk factors for plant growth and development in arid to semi-arid regions. Cultivation of salt tolerant crop genotypes is one of the imperative approaches to meet the food demand for increasing population. The current experiment was carried out to access the performance of different rice genotypes under salinity stress and Zinc (Zn) sources. Four rice genotypes were grown in a pot experiment and were exposed to salinity stress (7 dS m−1), and Zn (15 mg kg−1 soil) was applied from two sources, ZnSO4 and Zn-EDTA. A control of both salinity and Zn was kept for comparison. Results showed that based on the biomass accumulation and K+/Na+ ratio, KSK-133 and BAS-198 emerged as salt tolerant and salt sensitive, respectively. Similarly, based on the Zn concentration, BAS-2000 was reported as Zn-in-efficient while IR-6 was a Zn-efficient genotype. Our results also revealed that plant growth, relative water content (RWC), physiological attributes including chlorophyll contents, ionic concentrations in straw and grains of all rice genotypes were decreased under salinity stress. However, salt tolerant and Zn-in-efficient rice genotypes showed significantly higher shoot K+ and Zn concentrations under saline conditions. Zinc application significantly alleviates the harmful effects of salinity by improving morpho-physiological attributes and enhancing antioxidant enzyme activities, and the uptake of K and Zn. The beneficial effect of Zn was more pronounced in salt-tolerant and Zn in-efficient rice genotypes as compared with salt-sensitive and Zn-efficient genotypes. In sum, our results confirmed that Zn application increased overall plant’s performance under saline conditions, particularly in Zn in-efficient and tolerant genotypes as compared with salt-sensitive and Zn efficient rice genotypes.  相似文献   
53.
Gene delivery into hCD34+ hematopoietic stem/progenitor cells (HSPCs) using human immunodeficiency virus, type 1-derived lentiviral vectors (LVs) has several promising therapeutic applications. Numerous clinical trials are currently underway. However, the efficiency, safety, and cost of LV gene therapy could be ameliorated by enhancing target cell transduction levels and reducing the amount of LV used on the cells. Several transduction enhancers already exist, such as fibronectin fragments or cationic compounds. Recently, we discovered Vectofusin-1, a new transduction enhancer, also called LAH4-A4, a short histidine-rich amphipathic peptide derived from the LAH4 family of DNA transfection agents. Vectofusin-1 enhances the infectivity of lentiviral and γ-retroviral vectors pseudotyped with various envelope glycoproteins. In this study, we compared a family of Vectofusin-1 isomers and showed that Vectofusin-1 remains the lead peptide for HSPC transduction enhancement with LVs pseudotyped with vesicular stomatitis virus glycoproteins and also with modified gibbon ape leukemia virus glycoproteins. By comparing the capacity of numerous Vectofusin-1 variants to promote the modified gibbon ape leukemia virus glycoprotein-pseudotyped lentiviral vector infectivity of HSPCs, the lysine residues on the N-terminal extremity of Vectofusin-1, a hydrophilic angle of 140° formed by the histidine residues in the Schiffer-Edmundson helical wheel representation, hydrophobic residues consisting of leucine were all found to be essential and helped to define a minimal active sequence. The data also show that the critical determinants necessary for lentiviral transduction enhancement are partially different from those necessary for efficient antibiotic or DNA transfection activity of LAH4 derivatives. In conclusion, these results help to decipher the action mechanism of Vectofusin-1 in the context of hCD34+ cell-based gene therapy.  相似文献   
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55.
The aim of this study was to determine the serum levels of prolactin in patients with Behcet's disease and to evaluate its correlation with disease activity. Serum prolactin levels were measured by a chemiluminescence method in 32 patients with Behcet's disease and compared with 20 age-and sex-matched healthy controls. The patients with Behcet's disease were subdivided into two groups according to disease activity: active (18 patients; 13 men and five women, average age 34.0 +/- 6.5 (28-48) years), and inactive (14 patients; 10 men and four women, average age 32.7 +/- 3.1 (22-49 years). Patients with active Behcet's disease had higher serum prolactin levels than the inactive and control groups. Prolactin levels in patients with active Behcet's disease differed significantly from the healthy control subjects (p < 0.05) only, but not the inactive group. Four patients out of 32 (12.5%) Behcet's disease patients showed mild hyperprolactinemia. All four of these cases were from the active Behcet's disease group. Prolactin levels were correlated with ESR (p < 0.05) and CRP (p < 0.05) levels in the active BD group, but not in the inactive BD and control groups. Our results suggest a possible role for this immunoregulatory hormone in the disease expression and pathogenesis of Behcet's disease.  相似文献   
56.
Metabolites in the kynurenine pathway, generated by tryptophan degradation, are thought to play an important role in neurodegenerative disorders, including Alzheimer's and Huntington's diseases. In these disorders, glutamate receptor-mediated excitotoxicity and free radical formation have been correlated with decreased levels of the neuroprotective metabolite kynurenic acid. Here, we describe the synthesis and characterization of JM6, a small-molecule prodrug inhibitor of kynurenine 3-monooxygenase (KMO). Chronic oral administration of JM6 inhibits KMO in the blood, increasing kynurenic acid levels and reducing extracellular glutamate in the brain. In a transgenic mouse model of Alzheimer's disease, JM6 prevents spatial memory deficits, anxiety-related behavior, and synaptic loss. JM6 also extends life span, prevents synaptic loss, and decreases microglial activation in a mouse model of Huntington's disease. These findings support a critical link between tryptophan metabolism in the blood and neurodegeneration, and they provide a foundation for treatment of neurodegenerative diseases.  相似文献   
57.
The existing therapeutic agents for the management of pain and pyrexia are not very efficient and accompanied by numerous side effects. Thus, new effective agents are the most needed. The present study investigates bioactivities and phytochemical screening of different parts of Cissus assamica (Vitaceae), a Bangladeshi tribal medicinal plant. Three plant parts stems, leaves and roots were collected, washed, dried, powdered and then prepared for cold extraction. The methanolic stems and leaves extracts were fractioned with four and two solvents respectively. Different plant extracts were then investigated for in vivo antinociceptive activity and only methanolic leaves extract was investigated for in vivo antipyretic activity. In Swiss-albino mice, 200 and 400 mg/kg body weight doses were used for all extracts. In the peripheral antinociceptive activity, the methanolic stem extract and its dichloromethane, chloroform, pet ether fractions and methanolic roots extract at their both doses showed significant antinociceptive responses when compared to standard diclofenac sodium (60.49% inhibition). In the central antinociceptive activity, the response was found significant for methanolic stem and methanolic roots extract in their both doses compared to standard morphine. In antipyretic activity, methanolic leaves extract significantly reduced pyrexia level at 400 and 200 mg/kg body weight doses after two, three and 4 h of administration when compared to standard. So our findings indicate that this plant possesses noteworthy pharmacological activities which may be a basis for further researches to establish a possible mode of action of its different parts.  相似文献   
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59.
Bacterial seed and boll rot is a newly emerging cotton disease in Pakistan. Twenty-one cotton varieties were screened to find resistance source against the disease. None of these was found to be resistant. Five cotton varieties (CIM-595, MK2, BT-986, BT-986 & SG-1) having 700–1400 Area under disease progress curve (AUDPC) units were found to be moderately resistant to the disease. SLH-317, FH-942, BT-222, BT-666, MNH-457 ranging from 1401–1700 AUDPC units were moderately susceptible while MNH-456, SLH-336, 9811, FH-942, MNH-886 susceptible to boll rot. Seven varieties (FH-114, FH-113, BT-7, BT-212, SLH-BT-4, BT-212 and FH-941) were highly susceptible to bacterial seed and boll rot indicated by 2001–2300 AUDPC units. Biochemical tests identified bacterial isolates as Pantoea agglomerans. Different inoculation techniques were assessed for bacterial pathogenicity and symptoms of boll rot were only observed in needle punctured bolls. One, two and three weeks old bolls were mechanically inoculated by injecting bacterial suspension to evaluate the boll’s age impact on disease severity. Maximum severity was observed in two weeks old bolls. Red cotton bugs (Dysdercus cingulatus) were fed on artificially inoculated diseased bolls and then transferred on healthy bolls. Diseased symptoms were noticed on healthy cotton bolls. Bacterial colonies were recovered and red cotton bug was confirmed as the disease-transmitting vector.  相似文献   
60.
The possible changes in semen quality were studied in men living in a boron mining area. The subjects in the boron group had exposure to boron at an average level of 6.5 mg/day, as determined by urinary analysis. The results obtained by the boron group were compared to those obtained for the control group whose subjects were living in the same geographical area but away from the boron region; average exposure level was 1.4 mg/day for this group. The semen samples were analyzed according to the recommendations of the World Health Organization. Boron levels were established in the water samples obtained from various locations in the study region. In the boron mining fields where the subjects in the boron group live, water samples contained boron in the range of 1.4–6.5 mg/L, while the values were <0.01 mg/L for the water samples obtained from the region where the subjects of the control group reside. No negative effects were found in the sperm samples obtained from the subjects of the boron group.  相似文献   
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