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101.
Immature stages of the predacious mite, Neoseiulus californicus (McGregor) were reared on eggs of Tetranychus urticae Koch and gravid females were preserved on pollen of maize, Zea mays L. for 30, 45, 60 and 80?days. Afterwards, pollen was shifted to prey eggs for 15?days to evaluate their survival, fecundity and reproductive recovery period. All adult females of N. californicus survived the different maintenance periods and the following 15?days after pollen switch to the prey. Furthermore, predator females consuming pollen produced relatively few eggs during the preservation experiments, while they laid the majority of eggs during 15?days after pollen change to T. urticae without a second mating. The fecundity during the conservation periods significantly increased with increasing the maintenance period, whereas the reverse occurred subsequent to the shift to the prey. Moreover, the reproductive recovery period after the switch to T. urticae was inversely associated with the preservation period. Therefore, maize pollen is a useful alternative food for long-term survival and for maintaining fecundity of N. californicus females to exhibit an adequate numerical response to T. urticae at a subsequent time.  相似文献   
102.
The cotton bollworm Helicoverpa armigera (Hübner) is the most destructive pest of cotton, tomato and chickpea in Iran. In this study, the lethal and sublethal effects of thiacloprid were evaluated against cotton bollworm under laboratory condition at 26?±?1?°C, 70?±?5% RH and a photoperiod of 16:8 (L:D). Bioassay experiments were conducted on first larval instars by mixing the insecticide dilutions with artificial diet. The LC50 value of thiacloprid was 329?mg a.i./l. Sublethal effects of LC30 concentration of thiacloprid was studied on biological parameters. In the study of sublethal effects, thiacloprid at LC30 concentration significantly increased larval and pupal developmental times and reduced adults longevity compared with control but showed no significant effects on fecundity of cotton bollworm. Sublethal effects of thiacloprid also significantly reduced pupal weight compared with control. In general, sublethal effects studies showed that thiacloprid had adverse effects on biological parameters of the pest. Thus, our data suggest that thiacloprid had moderate potential against cotton bollworm.  相似文献   
103.
The Sidi Kassem Basin is the only limnic basin of Westphalian age in Morocco. It is built up of 1,250 m of alluvio-fluvial to lacustrine deposits that have so far yielded plant fossils and invertebrate remains only. Recent exploration for fossil tetrapod footprints in floodplain-deposits of the basin revealed a moderately diverse vertebrate ichnofauna composed of tracks assigned to cf. Batrachichnus Woodworth, 1900; cf. Hylopus Dawson, 1882; Dimetropus Romer and Price, 1940; and Notalacerta Butts, 1891. The tracks can be referred to temnospondyl, anamniote reptiliomorph, non-therapsid synapsid (pelycosaur), and captorhinomorph trackmakers. The described ichnoassemblage is important in at least three aspects: (1) It suggests an Early to mid-Pennsylvanian age for the footprint-bearing strata of the study area. (2) It is the oldest association of tetrapod footprints from Africa. (3) It is the first evidence of the relatively rare ichnogenera cf. Hylopus and Notalacerta outside of North America and Europe. Judged from the variety of tetrapod tracks and previously collected floral remains, the Sidi Kassem Basin must have represented a well-established continental ecosystem during Pennsylvanian time. Further exploration for trace and body fossils of Palaeozoic vertebrates in this basin may be important for the reconstruction of early tetrapod evolution.  相似文献   
104.
Journal of Molecular Histology - Osteoarthritis (OA) is a progressive degeneration of articular cartilage with involvement of synovial membrane, and subchondral bone. Current treatment approaches...  相似文献   
105.

Purpose

Human papillomavirus (HPV) is a major risk factor for specific cancers of the head and neck, particularly malignancies of the tonsil and base of the tongue. However, the role of HPV in the development of laryngeal cancer has not been definitively established. We conducted a population-based, cancer registry study to evaluate and characterize the genotype-specific prevalence of HPV in invasive laryngeal cancer cases diagnosed in the U.S.

Methods

The presence of genotype-specific HPV DNA was evaluated using the Linear Array HPV Genotyping Test and the INNO-LiPA HPV Genotyping Assay in formalin-fixed paraffin embedded tissue from 148 invasive laryngeal cancer cases diagnosed in 1993–2004 within the catchment area of three U.S. SEER cancer registries.

Results

HPV DNA was detected in 31 of 148 (21%) invasive laryngeal cancers. Thirteen different genotypes were detected. Overall, HPV 16 and HPV 33 were the most commonly detected types. HPV was detected in 33% (9/27) of women compared with 18% (22/121) of men (p = 0.08). After adjustment for age and year of diagnosis, female patients were more likely to have HPV-positive laryngeal tumors compared to males (adjusted OR 2.84, 95% CI 1.07–7.51). Viral genotype differences were also observed between the sexes. While HPV 16 and 18 constituted half of HPV-positive cases occurring in men, among women, only 1 was HPV 16 positive and none were positive for HPV 18. Overall 5-year survival did not vary by HPV status.

Conclusions

HPV may be involved in the development of a subset of laryngeal cancers and its role may be more predominant in women compared to men.  相似文献   
106.
BackgroundSevere acute malnutrition (SAM) is a major public health problem affecting children under the age of five in many low- and middle-income countries, and its resolution would contribute towards achieving the several sustainable development goals. The etiology of SAM is pluri-factorial, including delayed maturation of the gut microbiota, suboptimal feeding practices and dysfunctional breastfeeding. The recent serendipitous detection of Listeria monocytogenes in the breast milk of Malian women, in contrast to French women, suggests a possible association with SAM.Methodology/ Principal findingsTo investigate the possible association of L. monocytogenes carriage in breast milk and SAM, a case-control study was performed in Senegal, with subjects recruited from two areas. Using 16S amplicon sequencing, a culture independent method, 100% (152/152) of the mothers were positive for L. monocytogenes in their breast milk while qPCR analysis gave lower recovery rates. Interestingly, after enrichment in Fraser broth and seeding on PALCALM agar, all 10 isolated strains were isolated from the milk of 10 mothers who had SAM children which also had a significantly increased relative abundance of L. monocytogenes (0.34 (SD 0.35) vs 0.05 (SD 0.07) in controls, p<0.0001). The high genomic similarity between these strains and Malian breast milk strains from a previous study supports the hypothesis of endemic clone carriage in West Africa. Moreover, the in vitro growth inhibition of L. monocytogenes using breast milk samples was obtained from only 50% of the milk of mothers who had SAM children, in contrast to control samples which systematically inhibited the growth of L. monocytogenes with a higher inhibition diameter (15.7 mm (SD 2.3) in controls versus 3.5 mm (SD 4.6) in SAM, p = 0.0001). Lactobacillus and Streptococcus isolated from the breast milk of controls inhibit L. monocytogenes in a species-dependent manner.Conclusions/SignificanceOur study reveals a previously unsuspected carriage of L. monocytogenes in the breast milk of West African women, which is associated with SAM. The inhibitory effect of human selected lactic acid bacterial species against L. monocytogenes might provide new therapeutic and inexpensive options to prevent and treat this neglected public health issue.  相似文献   
107.
Habrobracon hebetor Say is one of the most important ectoparasitoids of the larval stage of many invasive agricultural pests such as noctuid and pyralid moths. Lethal and sublethal effects of carbaryl and abamectin were assessed on the ectoparasitoid H. hebetor in laboratory conditions. Dose–response bioassays were carried out on immature and adult stages by using dipping and contact residue methods, respectively. LC50 (lethal concentration for 50%) values of carbaryl and abamectin were 31.19 and 4.16 mg a.i. l−1 on larval stage and 12.6 and 4.42 mg a.i. l−1 on adults, respectively. In order to assess the sublethal effects, adult wasps were exposed to an LC30 of each insecticide and then the demographic parameters of live wasps were studied. The results showed that the intrinsic rate of increase (r m ), finite rate of increase (λ), net reproductive rate (R0) and gross reproductive rate (GRR) were significantly affected by the insecticides. The highest and the lowest r m values were 0.23 and 0.17 in control and carbaryl-treated insects, respectively. The sex ratio of H. hebetor offspring was not significantly affected by either insecticide. The results showed that carbaryl had more adverse effects on population parameters of the parasitoid compared to abamectin. Field studies are needed to determine the total effects of the pesticides on H. hebetor.  相似文献   
108.

Introduction

The aim of this study was to examine the effect of blocking Toll-like receptor 2 (TLR2) in rheumatoid arthritis (RA) synovial cells.

Methods

RA synovial tissue biopsies, obtained under direct visualization at arthroscopy, were established as synovial explant cultures ex vivo or snap frozen for immunohistology. Mononuclear cell cultures were isolated from peripheral blood and synovial fluid of RA patients. Cultures were incubated with the TLR1/2 ligand, Pam3CSK4 (200 ng, 1 and 10 μg/ml), an anti-TLR2 antibody (OPN301, 1 μg/ml) or an immunoglobulin G (IgG) (1 μg/ml) matched control. The comparative effect of OPN301 and adalimumab (anti-tumour necrosis factor alpha) on spontaneous release of proinflammatory cytokines from RA synovial explants was determined using quantitative cytokine MSD multiplex assays or ELISA. OPN301 penetration into RA synovial tissue explants cultures was assessed by immunohistology.

Results

Pam3CSK4 significantly upregulated interleukin (IL)-6 and IL-8 in RA peripheral blood mononuclear cells (PBMCs), RA synovial fluid mononuclear cells (SFMCs) and RA synovial explant cultures (P < 0.05). OPN301 significantly decreased Pam3CSK4-induced cytokine production of tumour necrosis factor alpha (TNF-α), IL-1β, IL-6, interferon (IFN)-γ and IL-8 compared to IgG control in RA PBMCs and SFMCs cultures (all P < 0.05). OPN301 penetration of RA synovial tissue cultures was detected in the lining layer and perivascular regions. OPN301 significantly decreased spontaneous cytokine production of TNF-α, IL-1β, IFN-γ and IL-8 from RA synovial tissue explant cultures (all P < 0.05). Importantly, the inhibitory effect of OPN on spontaneous cytokine secretion was comparable to inhibition by anti-TNFα monoclonal antibody adalimumab.

Conclusions

These findings further support targeting TLR2 as a potential therapeutic agent for the treatment of RA.  相似文献   
109.
The interaction of afatinib (AFB) with bovine serum albumin (BSA) was examined via fluorescence and UV-Vis spectroscopy. Spectrofluorimetric measurements revealed that AFB can strongly quench the BSA intrinsic fluorescence through producing a non-fluorescent complex. This quenching mechanism was thoroughly investigated with regard to the type of quenching, binding constant, number of binding locations and the fundamental thermodynamic parameters. Subsequently, the association constant of AFB with BSA was computed at three different temperatures and was found to range from 7.34 to 13.19 x105 L mol-1. Thermodynamic parameters calculations demonstrated a positive ΔSƟvalue with both negative ΔHϴand ΔGϴvalues for AFB–BSA complex, which in turn infers thata spontaneous binding is taking place with both electrostatic bonding and hydrophobic interactions participating in the binding of AFB and BSA. Similarly, the UV absorption spectra of AFB-BSA system were studied and confirmed the interaction. Conformational alteration of the protein upon binding to AFB was elaborated with the aid of three dimensional fluorescence measurements as well as synchronous fluorescence spectra.  相似文献   
110.
Whey protein concentrates (WPCs) enhance innate mucosal immunity during early life and have a protective role in some immune disorders. To further elucidate the potential benefits of this protein, the present study investigated the effect of dietary supplementation with WPCs on blood parameters, plasma cytokine profiles, and immune cell proliferation and chemotaxis. A total of 45 male mice were equally distributed into three experimental groups and treated daily for 21 days as follows: group I was a control group that was orally supplemented with distilled water, group II was orally supplemented with undenatured WP (100 mg/kg body weight), and group III was orally supplemented with bovine serum albumin (100 mg/kg body weight). We found that the plasma cytokine levels of interleukin (IL)-1α, IL-1β, IL-10 and tumor necrosis factor-α and the levels of reactive oxygen species, cholesterol, triglycerides and the lipid profile were significantly decreased in the WP-treated group compared to the control group. In contrast, the levels of IL-2, IL-4, IL-7, IL-8 and glutathione were significantly elevated, and consequently, the ability of peripheral blood mononuclear cells to proliferate in response to stimulation with different antigens was significantly increased in the WP-treated group. Moreover, the in vitro chemotaxis of B, T and bone-marrow-derived dendritic cells toward CC chemokine ligand-21 and CXC chemokine ligand-12 was significantly increased, by twofold, in WP-treated mice compared to the control group. Taken together, our data reveal the benefits of WP supplementation in enhancing immune cell proliferation and migration to the secondary lymphoid organs.  相似文献   
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