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1.
The effects of kisspeptin, an important regulator of reproductive function, and leptin, a classical metabolic hormone, on the formation of inducible regulatory T cells (iTreg) and T helper cells that produce interleukin 17 (Th17), as well as on the activity of indoleamine 2,3-dioxygenase (IDO) have been studied. Both hormones are actively produced by the placenta and involved in the formation of a new hormonal profile during pregnancy. It was found that kisspeptin at concentrations typical for trimesters I–III of pregnancy stimulates the formation of iTreg and simultaneously inhibit Th17 induction. Regardless of the used concentration, kisspeptin increases the secretion of interleukin-10 (IL-10) and reduces the production of IL-17A in CD4+ T lymphocytes in women. At the same time leptin at physiological concentrations typical for pregnancy has the opposite effect, inhibiting the formation of iTreg without affecting the production of IL-10 in cultures of CD4+T lymphocytes and simultaneous stimulating the induction of Th17 and production of IL-17A in CD4+T lymphocytes. At the concentration corresponding to trimesters II–III of pregnancy both hormones significantly enhance lipopolysaccharide-induced activity of IDO in monocytes.  相似文献   

2.
Paracoccidioidomycosis ceti is a cutaneous disease of cetaceans caused by uncultivated Paracoccidioides brasiliensis or Paracoccidioides spp. Serological cross-reactions between paracoccidioidomycosis ceti and paracoccidioidomycosis, paracoccidioidomycosis and histoplasmosis, and paracoccidioidomycosis and coccidioidomycosis have been reported before. The present study aimed to detect immunohistochemical cross-reaction between antibodies to Paracoccidioides sp. and Histoplasma capsulatum, and vice versa. Thirty murine sera, obtained from experimental infections of 6 isolates of H. capsulatum, were reacted with paraffin-embedded yeast-form cells of Paracoccidioides sp. derived from a case of paracoccidioidomycosis ceti in Japan. The murine sera were also reacted with human isolates of H. capsulatum yeast cells, with P. brasiliensis yeast cells, and with fungal cells of Coccidioides posadasii. Three dolphins’ sera from cases of paracoccidioidomycosis ceti, two human sera from patients with paracoccidioidomycosis, and a serum from a healthy person with a history of coccidioidomycosis were used in order to determine that the tested fungal cells reacted properly. Sera derived from mice infected with an isolate of H. capsulatum reacted positively against yeast cells of Paracoccidioides sp., yeast cells of P. brasiliensis, and fungal cells of C. posadasii, while those derived from other strains were negative. The present study recorded for the first time the cross-reaction between the yeast cells of H. capsulatum and antibodies against Paracoccidioides spp., the yeast cells of Paracoccidioides sp. and antibodies against H. capsulatum, the yeast cells of Paracoccidioides sp. and antibodies against Coccidioides sp., and fungal cells of C. posadasii and antibodies against Paracoccidioides spp.  相似文献   

3.
Nucleotide and amino acid sequences of Corynebacterium glutamicum recA genes, from GenBank, were compared in silico. On the basis of the identity found between sequences, two degenerate primers were designed on the two sides of the deduced open reading frame (ORF) of the recA gene. PCR experiments, for amplifying the recA ORF region, were done. pGEM®-T Easy vector was selected to be used for cloning PCR products. Then recA ORF was placed under the control of Escherichia coli hybrid trc promoter, in pKK388-1 vector. pKK388-1 vector, containing recA ORF, was transformed to E. coli DH5α ΔrecA (recombinant deficient strain), in an attempt to phenotypically complement it. Ultraviolet (u.v.) exposure experiments of the transformed and non-transformed E. coli DH5α ΔrecA cells revealed tolerance of transformed cells up to dose 0.24 J/cm2, while non-transformed cells tolerated only up to dose 0.08 J/cm2. It is concluded that phenotypic complementation of E. coli DH5α ΔrecA with recA ORF of C. glutamicum, could be achieved and RecA activity could be restored.  相似文献   

4.
Aedes aegypti (L.) is the main vector of tropical diseases such as dengue, chikungunya and Zika. Due to the overuse of insecticides, Ae. aegypti resistant populations have increased. Biological control with Lysinibacillus sphaericus (Ahmed) has been used against Culex sp. and Anopheles sp. Although Ae. aegypti is refractory to the binary toxin of L. sphaericus spores, vegetative cells have been shown to be effective against Ae. aegypti larvae. In this work, the effect of L. sphaericus vegetative cells on Ae. aegypti temephos-resistant larvae was assessed under lab and simulated field conditions. L. sphaericus caused about 90% mortality of insecticide-resistant Ae. aegypti larvae under simulated field conditions. Likewise, Ae. aegypti larvae were more sensitive to mixed cultures of L. sphaericus than to individual strains; then, the most effective mixed culture exhibited an LC50 of 1.21 × 105 CFU/mL with Rockefeller larvae and 8.04 × 104 CFU/mL with field-collected larvae. Additionally, we found that mixed cultures composed of two L. sphaericus strains were more effective than a culture formed by the three strains. Our results suggest that mixed cultures comprising L. sphaericus vegetative cells could be useful for controlling temephos-resistant populations of Ae. aegypti, as evidenced by the effectiveness demonstrated under laboratory and simulated field conditions.  相似文献   

5.
In vitro studies suggest that delayed hypersensitivity follows the production of migration inhibitory factor (MIF) by sensitive lymphocytes in the presence of specific antigen. This factor arrests the migration of macrophages in vitro and in vivo. After attraction, aggregation and activation in vivo, these bystander cells produce toxic substances which induce the local reaction1. When lymphocytes from tuberculin (PPD) sensitized guinea-pigs were incubated with PPD, cell-free supernatant fluids of the cultures contained MIF2. Such migration inhibitory fluids injected intradermally with PPD, into PPD-sensitive animals, enhanced the delayed hypersensitivity reaction3. Concentrated migration inhibitory supernatant fluids injected intradermally into unsensitized animals produced local reactions of induration and erythema within 6 h; reactions reached a maximum after 16 h. Histologically there was an infiltrate of mononuclear cells at the site of injection and neutrophils and eosinophils were also present1.  相似文献   

6.
BioUD ® with the active ingredient 2-undecanone originally derived from wild tomato plants is a new repellent recently registered by the US EPA. Repellent efficacy of BioUD ® (7.75% 2-undecanone) and DEET (98.11%) was examined in the laboratory using a choice test between repellent-treated and control filter paper surfaces for Amblyomma americanum, Dermacentor variabilis, and Ixodes scapularis. BioUD ® provided greater repellency against A. americanum and I. scapularis than DEET. No difference was found between BioUD ® and DEET against D. variabilis. In head-to-head assays between BioUD ® and DEET, undiluted and 50% dilutions of BioUD® were more repellent than undiluted DEET against all three species tested. Similarly, a 25% dilution of BioUD® was more repellent than DEET against A. americanum while no difference in mean percentage repellency was found between a 25% dilution of BioUD® and DEET against I. scapularis. Based on regression analysis, the concentration of BioUD® required for equivalent repellency to 98.11% DEET was 39.5% for D. variabilis and 29.7% for I. scapularis. A log-probit model could not be constructed for A. americanum from the dosages tested. Based on filter paper head-to-head assays, BioUD® is at least 2–4 times more active as a repellent than DEET against three species of ixodid ticks under the conditions of our laboratory bioassays.  相似文献   

7.
The probiotic properties and inhibitory effect on Salmonella Typhimurium adhesion on human enterocyte-like HT-29-Luc cells of three Lactobacillus plantarum strains isolated from fermented fish, beach sand and a coastal plant were determined. Compared with the type strain L. plantarum NBRC 15891T, which was isolated from pickled cabbage, L. plantarum Tennozu-SU2 isolated from the acorn of a coastal tree showed high autoaggregation in de Man, Rogosa and Sharpe (MRS) broth and an antagonistic effect against S. Typhimurium in brain heart infusion (BHI) broth. Furthermore, heat-killed L. plantarum Tennozu-SU2 cells inhibited S. Typhimurium adhesion on HT-29-Luc cells. Both live and heat-killed L. plantarum Tennozu-SU2 cells showed an inhibitory effect on gut colonisation in BALB/c mice, as assessed by viable Salmonella count in faecal samples and by invasion into liver and spleen tissues. The properties shown in this study suggest that L. plantarum Tennozu-SU2 is useful as a starter and probiotic bacteria in functional food material.  相似文献   

8.
9.
Leishmania amazonensis is the etiologic agent of cutaneous leishmaniasis, an immune-driven disease causing a range of clinical symptoms. Infections caused by L. amazonensis suppress the activation and function of immune cells, including macrophages, dendritic cells, and CD4+ T cells. In this study, we analyzed the course of infection as well as the leishmanicidal effect of intralesional UTP treatment in L. amazonensis-infected BALB/c mice. We found that UTP treatment reduced the parasitic load in both footpad and lymph node sites of infection. UTP also boosted Th1 immune responses, increasing CD4+ T cell recruitment and production of IFN-γ, IL-1β, IL-12, and TNF-α. In addition, the role of UTP during innate immune response against L. amazonensis was evaluated using the air pouch model. We observed that UTP augmented neutrophil chemoattraction and activated microbicidal mechanisms, including ROS production. In conclusion, our data suggested an important role for this physiological nucleotide in controlling L. amazonensis infection, and its possible use as a therapeutic agent for shifting immune responses to Th1 and increasing host resistance against L. amazonensis infection.  相似文献   

10.
The antifungal activity of Solanum melongena leaf, extracted with petroleum ether, chloroform, methanol and water was evaluated against three human pathogenic dermatophytes namely Trichophyton mentagrophytes, T. rubrum and T. tonsurans and two opportunistic fungi Candida albicans and Trichosporon beigelii. Maximum yield of plant components was 4.32 g, extracted in water and minimum 1.07 g in petroleum ether from 150 g of dry plant material. Except water extract, all the extracts possessed significant antifungal property. All the test pathogens showed highest sensitivity towards chloroform extract, exhibiting maximum inhibition zone diameter of 50.0 mm in T. mentagrophytes and minimum 30.0 mm in C. albicans at 2 × 105 μg/ml concentration. Chloroform extract at lower concentration 2.5 × 104 μg/ml was inhibitory for all the test pathogens, exhibiting inhibition zone diameter 21.0 mm against T. tonsurans and 15.0 mm against C. albicans and T. beigelii. The activity of the different solvent extracts against the test pathogens in terms of inhibition zone diameter in decreasing order was as followsChloroform extract > Petroleum ether extract > Methanol extract for T. mentagrophytes, T. rubrum and T. tonsurans.Chloroform extract > Methanol extract > Petroleum ether extract for C. albicans and T. beigelii.  相似文献   

11.
Single cells of five different Microcystis species (M. ichthyoblabe, M. viridis, M. flos-aquae, M. wesenbergii, and M. aeruginosa) were batch-cultured at different temperatures and light intensities: (a) 25 °C and 50 μmol photons m?2 s?1 (control culture); (b) 25 °C and 10 μmol photons m?2 s?1; and (c) 15 °C and 50 μmol photons m?2 s?1. The extracellular polysaccharide content was significantly higher in treatments b and c than in the control treatment. All Microcystis species existed as single cells under the control treatment but formed colonies in treatments b and c. All of the colonies were irregular with indistinct margins. M. ichthyoblabe, M. viridis, M. flos-aquae, and M. wesenbergii formed colonies with similar morphologies and their cells were loosely aggregated. In contrast, M. aeruginosa formed denser colonies with no distinct holes. The colony morphologies differed from the classic morphology of M. ichthyoblabe field-grown colonies but resembled that of small colonies found in Lake Taihu (Yangtze Delta Plain, China) during early spring. This indicates that field- and laboratory-grown colonies are governed by similar formation processes. We suggest that in laboratory and field environments, M. ichthyoblabe (or M. flos-aquae) colonies are representative of small colonies formed from single Microcystis cells, whereas the morphology of older colonies evolves to resemble M. wesenbergii and M. aeruginosa colonies.  相似文献   

12.
CELLS from patients with G-trisomy or E-trisomy and XXY cells from patients with XY/XXY mosaic Klinefelter's syndrome are more susceptible to transformation in vitro by SV40 than are cells from normal individuals1–3. We have used triploid (69XXY) human cells to determine whether the presence of extra chromosomes per se increases susceptibility to transformation.  相似文献   

13.
Bacillus thuringiensis (Berliner) bears essential characteristics in the control of insect pests, such as its unique mode of action, which confers specificity and selectivity. This study assessed cry gene contents from Bt strains and their entomotoxicity against Diatraea saccharalis (F.) and Diatraea flavipennella (Box) (Lepidoptera: Crambidae). Bioassays with Bt strains were performed against neonates to evaluate their lethal and sublethal activities and were further analyzed by PCR, using primers to identify toxin genes. For D. saccharalis and D. flavipennella, 16 and 18 strains showed over 30% larval mortality in the 7th day, respectively. The LC50 values of strains for D. saccharalis varied from 0.08 × 105 (LIIT-0105) to 4104 × 105 (LIIT-2707) spores + crystals mL?1. For D. flavipennella, the LC50 values of strains varied from 0.40 × 105 (LIIT-2707) to 542 × 105 (LIIT-2109) spores + crystals mL?1. For the LIIT-0105 strain, which was the most toxic to D. saccharalis, the genes cry1Aa, cry1Ab, cry1Ac, cry1B, cry1C, cry1D, cry1F, cry1I, cry2Aa, cry2Ab, cry8, and cry9C were detected, whereas for the strain LIIT-2707, which was the most toxic to D. flavipennella, detected genes were cry1Aa, cry1Ab, cry1Ac, cry1B, cry1D, cry1F, cry1I, cry2Aa, cry2Ab, and cry9. The toxicity data and toxin gene content in these strains of Bt suggest a great variability of activity with potential to be used in the development of novel biopesticides or as source of resistance genes that can be expressed in plants to control pests.  相似文献   

14.
15.
The exocyst, an octameric protein complex consisting of Exoc1 through Exoc8, was first determined to regulate exocytosis by targeting vesicles to the plasma membrane in yeast to mice. In addition to this fundamental role, the exocyst complex has been implicated in other cellular processes. In this study, we investigated the role of the exocyst in cochlear development and hearing by targeting EXOC5, a central exocyst component. Deleting Exoc5 in the otic epithelium with widely used Cre lines resulted in early lethality. Thus, we generated two different inner ear-specific Exoc5 knockout models by crossing Gfi1Cre mice with Exoc5f/f mice for hair cell-specific deletion (Gfi1Cre/+;Exoc5f/f) and by in utero delivery of rAAV-iCre into the otocyst of embryonic day 12.5 for deletion throughout the otic epithelium (rAAV2/1-iCre;Exoc5f/f). Gfi1Cre/+;Exoc5f/f mice showed relatively normal hair cell morphology until postnatal day 20, after which hair cells underwent apoptosis accompanied by disorganization of stereociliary bundles, resulting in progressive hearing loss. rAAV2/1-iCre;Exoc5f/f mice exhibited abnormal neurite morphology, followed by apoptotic degeneration of spiral ganglion neurons (SGNs) and hair cells, which led to profound and early-onset hearing loss. These results demonstrate that Exoc5 is essential for the normal development and survival of cochlear hair cells and SGNs, as well as the functional maintenance of hearing.  相似文献   

16.
The synthesis and antibacterial activity of some new benzo[5,6]chromeno[2,3-d]pyrimidine derivatives are described. The title compounds were obtained by the reaction of 1H-benzo[f]chromenes with aliphatic and aromatic amines. The structures of all newly synthesized compounds were confirmed by IR, 1HNMR, 13C NMR, and NOESY experiments. The compounds exhibited potent antibacterial activity against gram-positive and gram-negative bacterial species. 10-Methyl-12-(4-hydroxyphenyl)-10,12-dihydro-11H-benzo[5,6]chromeno[2,3-d] pyrimidin-11-imine displayed greater antibacterial activity against gramnegative bacterial species than did ciprofloxacinandamoxicillin.  相似文献   

17.
Bone morphogenetic protein 1 (BMP1) and tolloid-like 1 (TLL1) belong to the BMP1/tolloid-like proteinase family, which cleaves secretory proteins. The constitutive deletion of the Bmp1 or Tll1 genes causes perinatal or embryonic lethality in mice. In this study, we first studied the β-galactosidase activity in mice in which an IRES-lacZ-Neo cassette was inserted in the intron of either the Bmp1 or the Tll1 gene; the β-galactosidase activities were used to reflect the expression of endogenous Bmp1 and Tll1, respectively. Our X-gal staining results showed that the odontoblasts in the tooth and cells in the periodontal ligament express both Bmp1 and Tll1. We then created Bmp1 flox/flox and Tll1 flox/flox mice by removing the IRES-lacZ-Neo cassette. By breeding 2.3 kb Col1a1-Cre mice with the Bmp1 flox/flox and Tll1 flox/flox mice, we further generated Col1a1-Cre;Bmp1 flox/flox ;Tll1 flox/flox mice in which both Bmp1 and Tll1 were inactivated in the Type I collagen-expressing cells. We employed X-ray radiography, histology and immunohistochemistry approaches to characterize the Col1a1-Cre;Bmp1 flox/flox ;Tll1 flox/flox mice. Our results showed that the molars of the Col1a1-Cre;Bmp1 flox/flox ;Tll1 flox/flox mice had wider predentin, thinner dentin and larger pulp chambers than those of the normal controls. The dentinal tubules of the molars in the Col1a1-Cre;Bmp1 flox/flox ;Tll1 flox/flox mice appeared disorganized. The level of dentin sialophosphoprotein in the molars of the 6-week-old Col1a1-Cre;Bmp1 flox/flox ;Tll1 flox/flox mice was lower than in the normal controls. The periodontal ligaments of the Col1a1-Cre;Bmp1 flox/flox ;Tll1 flox/flox mice were disorganized and had less fibrillin-1. Our findings indicate that the proteinases encoded by Bmp1 and Tll1 genes play essential roles in the development and maintenance of mouse dentin and periodontal ligaments.  相似文献   

18.
In congenital hyperinsulinism of infancy (CHI), the loss of K-ATP channels (composed of Kir6.2 and SUR1 subunits) in β cells induces permanent insulin secretion and severe hypoglycaemia. By contrast, Sur1 ?/? mice do not present such defects. We have investigated the impact of Sur1 gene inactivation on mouse islet cell morphology, structure and basic physiology. Pancreata were collected from young, adult and old wild-type (WT) and Sur1 ?/? mice. After immunostaining for hormone, the total endocrine tissue, cell proportion, cell size and intra-insular distribution, hormone content and Glut-2 expression were quantified by morphometry. Basic physiological parameters were also measured. In young Sur1 ?/? mice, the total endocrine tissue and proportion of β cells were higher (P<0.05) than in WT mice, whereas the proportion of δ cells was lower (P<0.01). In old Sur1 ?/? mice, α cells were frequently located in the central regions of islets (unlike WT islets) and their proportion was increased (P<0.05). Glut-2 protein and mRNA levels were lower in old Sur1 ?/? islets (P<0.02). Insulinaemia, fasting insulin and glucagon contents were equivalent in both groups of pancreata. Thus, the islets of Sur1 ?/? mice present morphological modifications that have not been described in CHI and that might reflect an adaptive mechanism controlling insulin secretion in these mice.  相似文献   

19.
Physicochemical and microbiological characteristics of formation waters low-temperature heavy oil reservoirs (Russia) were investigated. The Chernoozerskoe, Yuzhno-Suncheleevskoe, and Severo-Bogemskoe oilfields, which were exploited without water-flooding, were shown to harbor scant microbial communities, while microbial numbers in the water-flooded strata of the Vostochno-Anzirskoe and Cheremukhovskoe oilfields was as high as 106 cells/mL. The rates of sulfate reduction and methanogenesis were low, not exceeding 1982 ng S2–/(L day) and 9045 nL СН4/(L day), respectively, in the samples from water-flooded strata. High-throughput sequencing of microbial 16S rRNA gene fragments in the community of injection water revealed the sequences of the Proteobacteria (74.7%), including Betaproteobacteria (40.2%), Alphaproteobacteria (20.7%), Gammaproteobacteria (10.1%), Deltaproteobacteria (2.0%), and Epsilonproteobacteria (1.6%), as well as Firmicutes (7.9%), Bacteroidetes (4.1%), and Archaea (0.2%). DGGE analysis of microbial mcrA genes in the community of injection water revealed methanogens of the genera Methanothrix, Methanospirillum, Methanobacterium, Methanoregula, Methanosarcina, and Methanoculleus, as well as unidentified Thermoplasmata. Pure cultures of bacteria of the genera Rhodococcus, Pseudomonas, Gordonia, Cellulomonas, etc., capable of biosurfactant production when grown on heavy oil, were isolated. Enrichment cultures of fermentative bacteria producing significant amounts of volatile organic acids (acetic, propionic, and butyric) from sacchariferous substrates were obtained. These acids dissolve the carbonates of oil-bearing rock efficiently. Selection of the efficient microbial technology for enhanced recovery of heavy oil from terrigenous and carbonate strata requires model experiments with microbial isolates and the cores of oil-bearing rocks.  相似文献   

20.
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