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1.
A four-way, double-blind, prospective trial of treatment of abscesses by incision, curettage, and primary closure with and without antibiotic cover (clindamycin injection before operation or capsules after operation, or both) was conducted. There was no appreciable difference in mean healing time between the patients given both the antibiotic injection and the antibiotic capsules and those given the injection and placebo capsules, whereas healing times in those given the placebo injection and antibiotic capsules or placebo only were appreciably longer. Four of the patients who were not given the antibiotic injection developed bacteraemia; one patient who was given the antibiotic injection also developed a bacteraemia, but this was caused by clindamycin-resistant bacteria. These results show that a single injection of an effective antibiotic before operation is sufficient to protect the patient against bacteraemia and permit optimum healing.  相似文献   
2.
This work aimed to co-digest various wastes to assess the best combination of all mixing ratio, also at choosing the best ratio between untreated primary sludge (UPS) singly from two sources, (South valley University (SUPS) and Abu tesht wastewater station (AUPS) and raw chicken manure (RCM) and comparing the results in either case. The co-digestions of untreated primary sludge from Abu tesht wastewater treatment stations with different levels of raw chicken manure (0:100, 10:90, 30:70, 50:50, 90:10, and 100:0) to obtain the best mixtures. Also, co-digestion of untreated primary sludge from south valley university with different levels of raw chicken manure at the same ratios, to obtain the best mixtures. Batch digestion tests were applied in 2.5 L digester with a working volume of 2.0 L. The samples in triplicates were separately loaded into the digesters locally fabricated and kept for 20 days as a retention period and diluted with the same amount of water. Mesophilic under 35 °C was adopted for untreated primary sludge as well as mixtures with raw chicken manure based on total solids (TS) and volatile solid (VS) proportions. The average biogas yields from AUPS/RCM mixture obtained ranged from 8570 to 5600 ml, by the following descending order, 10: 90 > 90:10 and so on >100:0, and the average biogas yields from SUPS/RCM obtained ranged from 6330 to 5635 ml, in the order of 90: 10 > 10:90 and so on >100:0. The results showed highest biogas yield from AUPS/RCM and SUPS/RCM mixtures with mixing ratio of 10:90 and 90:10, respectively, however, the lowest biogas production detected in separate digestion of AUPS and SUPS. The results indicated that co-digestion between the sludge and raw chicken manure could increase total biogas production volume, enhance sludge treatment process, and produce eco-friendly sludge because of co-digestion process than separate processing of each feedstock.  相似文献   
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Pandemic A (H1N1) 2009 influenza virus (pH1N1) infection in pregnant women can be severe. The mechanisms that affect infection outcome in this population are not well understood. To address this, pregnant and nonpregnant BALB/c mice were inoculated with the wild-type pH1N1 strain A/California/04/09. To determine whether innate immune responses are associated with severe infection, we measured the innate cells trafficking into the lungs of pregnant versus nonpregnant animals. Increased infiltration of pulmonary neutrophils and macrophages strongly correlated with an elevated mortality in pregnant mice. In agreement with this, the product of nitric oxide (nitrite) and several cytokines associated with recruitment and/or function of these cells were increased in the lungs of pregnant animals. Surprisingly, increased mortality in pregnant mice was not associated with higher virus load because equivalent virus titers and immunohistochemical staining were observed in the nasal cavities or lungs of all mice. To determine whether exacerbated inflammatory responses and elevated cellularity resulted in lung injury, epithelial regeneration was measured. The lungs of pregnant mice exhibited reduced epithelial regeneration, suggesting impaired lung repair. Despite these immunologic alterations, pregnant animals demonstrated equivalent percentages of pulmonary influenza virus-specific CD8(+) T lymphocytes, although they displayed elevated levels of T-regulator lymphocytes (Tregs) in the lung. Also, pregnant mice mounted equal antibody titers in response to virus or immunization with a monovalent inactivated pH1N1 A/California/07/09 vaccine. Therefore, immunopathology likely caused by elevated cellular recruitment is an implicated mechanism of severe pH1N1 infection in pregnant mice.  相似文献   
5.
For decades, mesenchymal stem (MSCs) cells have been used for cardiovascular diseases as regenerative therapy. This review is an attempt to summarize the types of MSCs involved in myocardial infarction (MI) therapy, as well as its possible mechanisms effects, especially the paracrine one in MI focusing on the studies (human and animal) conducted within the last 10 years. Recently, reports showed that MSC therapy could have infarct‐limiting effects after MI in both experimental and clinical trials. In this context, various types of MSCs can help cardiac regeneration by either revitalizing the cardiac stem cells or revascularizing the arteries and veins of the heart. Furthermore, MSCs could produce paracrine growth factors that increase the survival of nearby cardiomyocytes, as well as increase angiogenesis through recruitment of stem cell from bone marrow or inducing vessel growth from existing capillaries. Recent research suggests that the paracrine effects of MSCs could be mediated by extracellular vesicles including exosomes. Exosomal microRNAs (miRNAs) released by MSCs are promising therapeutic hotspot target for MI. This could be attributed to the role of miRNA in cardiac biology, including cardiac regeneration, stem cell differentiation, apoptosis, neovascularization, cardiac contractility and cardiac remodeling. Furthermore, gene‐modified MSCs could be a recent promising therapy for MI to enhance the paracrine effects of MSCs, including better homing and effective cell targeted tissue regeneration. Although MSC therapy has achieved considerable attention and progress, there are critical challenges that remains to be overcome to achieve the most effective successful cell‐based therapy in MI.  相似文献   
6.
Molecular machines within cells dynamically assemble, disassemble and reorganize. Molecular interactions between their components can be observed at the single-molecule level and quantified using colocalization single-molecule spectroscopy, in which individual labeled molecules are seen transiently associating with a surface-tethered partner, or other total internal reflection fluorescence microscopy approaches in which the interactions elicit changes in fluorescence in the labeled surface-tethered partner. When multiple interacting partners can form ternary, quaternary and higher order complexes, the types of spatial and temporal organization of these complexes can be deduced from the order of appearance and reorganization of the components. Time evolution of complex architectures can be followed by changes in the fluorescence behavior in multiple channels. Here, we describe the kinetic event resolving algorithm (KERA), a software tool for organizing and sorting the discretized fluorescent trajectories from a range of single-molecule experiments. KERA organizes the data in groups by transition patterns, and displays exhaustive dwell time data for each interaction sequence. Enumerating and quantifying sequences of molecular interactions provides important information regarding the underlying mechanism of the assembly, dynamics and architecture of the macromolecular complexes. We demonstrate KERA’s utility by analyzing conformational dynamics of two DNA binding proteins: replication protein A and xeroderma pigmentosum complementation group D helicase.  相似文献   
7.
Edwardsiella ictaluri is a Gram‐negative facultative anaerobe that can survive inside channel catfish phagocytes. E. ictaluri can orchestrate Type VI Secretion System (T6SS) for survival in catfish macrophages. evpP encodes one of the T6SS translocated effector proteins. However, the role of evpP in E. ictaluri is still unexplored. In this work, we constructed an E. ictaluri evpP mutant (EiΔevpP) and assessed its survival under complement and oxidative stress. Persistence of EiΔevpP in catfish as well as attachment and invasion in catfish macrophage and ovary cells were determined. Further, virulence of EiΔevpP in catfish and apoptosis it caused in macrophages were explored. EiΔevpP behaved same as wild type (EiWT) under complement and oxidative stress in complex media, whereas oxidative stress affected mutant's survival significantly in minimal media (p < .05). Persistence of EiΔevpP in live catfish and uptake and survival inside peritoneal macrophages were similar. The attachment and invasion capabilities of EiΔevpP in catfish ovary cells were significantly less than that of EiWT (p < .05). Although EiΔevpP showed reduced attenuation in catfish, causing decreased catfish mortality compared with EiWT (44.73% vs. 67.53%), this difference was not significant. The apoptosis assay using anterior kidney macrophages indicated that the number of live macrophages exposed to EiΔevpP was significantly higher compared with EiWT exposed macrophages at 24‐hr post‐treatment (p < .05). However, there were no significant differences in the early and late apoptosis. Remarkably, necrosis in EiΔevpP exposed macrophages was significantly less than that of EiWT exposed macrophages at 24 hr (p < .05). Our results demonstrated that evpP is required for colonisation of catfish ovary cells and increased apoptosis and necrosis in anterior kidney macrophages.  相似文献   
8.
ABSTRACT

Gibberellins are commonly used plant growth regulators that exhibit deleterious effects on various animal tissues. We investigated the histological, immunohistochemical and biochemical effects of gibberellic acid (GA3) on rat testes as well as the possible protective role of pomegranate peel extract (PPE). We used 28 adult male rats divided into control, PPE treated, GS3 treated and GA3 + PPE treated groups. Testis specimens were analyzed for superoxide dismutase (SOD) and catalase (CAT) activity, and examined histologically. We also investigated the androgen receptor using immunohistochemistry. The GA3 treated group exhibited significantly decreased SOD and CAT levels and area percent of androgen receptor. Seminiferous tubules (ST) were widely separated and the germinal epithelium was separated from the basement membrane in some tubules. Areas of vacuolation, degenerated germ cells with pyknotic nuclei and large multinucleated cells were observed. Ultrastructurally, primary spermatocytes exhibited vacuolated cytoplasm, degenerated mitochondria and hyperchromatic nuclei. Degenerated early spermatids with a ruptured or hyperchromatic nucleus were found. Spermatozoa exhibited abnormalities of the head and tail. The cytoplasm of Sertoli and Leydig cells exhibited dilated smooth endoplasmic reticulum. A significant improvement of the biochemical, histological and immunohistochemical alterations was observed in the GA3 + PPE treated group compared to the GA3 treated group.  相似文献   
9.
Granulosa-theca cell tumors (GTCTs) are the most frequently reported ovarian tumors in cattle. Clinically, GTCTs could be confused with other ovarian abnormalities; therefore, the only definitive diagnosis for such tumors is histopathology of a biopsy from the affected ovary. However, this is an invasive technique and unsuitable for farm conditions. As a result, the key aim of this study was to evaluate the diagnostic value of anti-Müllerian hormone (AMH), a glycoprotein hormone that is synthesized exclusively by ovarian granulosa cells, as a sensitive noninvasive biomarker for diagnosing GTCTs in cattle. To achieve this aim, we conducted two experiments. In experiment 1, four clinically healthy Japanese Black cows had blood samples taken daily over one estrous cycle to characterize their AMH profiles throughout the estrous cycle. Additionally, single blood samples were collected from 21 cyclic cows to clarify the physiological range of AMH. In experiment 2, cows with histologically confirmed GTCT (GTCT group, n = 9) and cows affected with cystic ovarian disease (COD group, n = 8) had one blood sample taken before extraction of the tumorous ovary or therapeutic treatment for the COD. Blood samples (n = 105) from cyclic cows (n = 25) in experiment 1 were assigned as a physiologically cyclic group (PC group). Plasma AMH, immunoreactive inhibin (ir-INH), estradiol-17β (E2), testosterone (T), and progesterone (P4) concentrations were assayed in all samples. In experiment 1, the mean plasma AMH concentration was 0.09 ± 0.003 ng/mL and did not show substantial fluctuation throughout the estrous cycle. In experiment 2, plasma AMH, ir-INH, and E2 concentrations were significantly elevated in the GTCT group in comparison with the PC group; among these parameters, only the AMH concentrations were significantly higher in the GTCT group than in the COD group. The area under the receiver operating characteristic curve of AMH for diagnosis of GTCT was 0.99 and was significantly higher than that of ir-INH (P < 0.001) and E2 (P < 0.01). Moreover, the AMH at a cutoff point of ≥0.36 ng/mL had the highest diagnostic accuracy (99.2%), sensitivity (100%), and specificity (99.1%) compared with the other tested parameters. In conclusion, plasma AMH concentration is probably a more reliable and sensitive biomarker for bovine GTCTs than the concentrations of ir-INH or ovarian steroids.  相似文献   
10.
Anterior chamber-associated immune deviation (ACAID) is a form of peripheral tolerance that is induced by introducing Ags into the anterior chamber (AC) of the eye, and is maintained by Ag-specific regulatory T cells (Tregs). ACAID regulates harmful immune responses that can lead to irreparable injury to innocent bystander cells that are incapable of regeneration. This form of immune privilege in the eye is mediated through Tregs and is a product of complex cellular interactions. These involve F4/80+ ocular APCs, B cells, NKT cells, CD4+CD25+ Tregs, and CD8+ Tregs. gammadelta T cells are crucial for the generation of ACAID and for corneal allograft survival. However, the functions of gammadelta T cells in ACAID are unknown. Several hypotheses were proposed for determining the functions of gammadelta T cells in ACAID. The results indicate that gammadelta T cells do not cause direct suppression of delayed-type hypersensitivity nor do they act as tolerogenic APCs. In contrast, gammadelta T cells were shown to secrete IL-10 and facilitate the generation of ACAID Tregs. Moreover, the contribution of gammadelta T cells ACAID generation could be replaced by adding exogenous recombinant mouse IL-10 to ACAID spleen cell cultures lacking gammadelta T cells.  相似文献   
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