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991.
A feeding trial was conducted to investigate the effects of different levels of dietary Lactobacillus plantarum on hemato-immunological parameters and resistance against Streptococcus iniae infection in juvenile Siberian sturgeon Acipenser baerii. Fish (14.6 ± 2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations [1 × 107, 1 × 108 and 1 × 109 colony-forming units (cfu) g?1] and a control (non-supplemented basal) diet for 8 weeks. Innate immune responses (immunoglobulin (Ig), alternative complement activity (ACH50) and lysozyme activity) were significantly higher in fish fed the 1 × 108 and 1 × 109 cfu g?1 L. plantarum diet compared to the other groups (P < 0.05). Furthermore, fish fed on various levels of L. plantarum significantly showed higher red blood cell (RBC), hemoglobin (Hb), white blood cell (WBC) and monocyte compared to those of the control group (P < 0.05). At the end of the feeding experiment, some fish were challenged with S. iniae to quantify the level of disease resistance. The mortality after S. iniae challenge was decreased in fish fed a probiotic. These results indicated that dietary supplementation of L. plantarum improved immune response and disease resistance of Siberian sturgeon juvenile.  相似文献   
992.

Background

Climate change causes the breakdown of the symbiotic relationships between reef-building corals and their photosynthetic symbionts (genus Symbiodinium), with thermal anomalies in 2015–2016 triggering the most widespread mass coral bleaching on record and unprecedented mortality on the Great Barrier Reef. Targeted studies using specific coral stress indicators have highlighted the complexity of the physiological processes occurring during thermal stress, but have been unable to provide a clear mechanistic understanding of coral bleaching.

Results

Here, we present an extensive multi-trait-based study in which we compare the thermal stress responses of two phylogenetically distinct and widely distributed coral species, Acropora millepora and Stylophora pistillata, integrating 14 individual stress indicators over time across a simulated thermal anomaly. We found that key stress responses were conserved across both taxa, with the loss of symbionts and the activation of antioxidant mechanisms occurring well before collapse of the physiological parameters, including gross oxygen production and chlorophyll a. Our study also revealed species-specific traits, including differences in the timing of antioxidant regulation, as well as drastic differences in the production of the sulfur compound dimethylsulfoniopropionate during bleaching. Indeed, the concentration of this antioxidant increased two-fold in A. millepora after the corals started to bleach, while it decreased 70% in S. pistillata.

Conclusions

We identify a well-defined cascading response to thermal stress, demarking clear pathophysiological reactions conserved across the two species, which might be central to fully understanding the mechanisms triggering thermally induced coral bleaching. These results highlight that bleaching is a conserved mechanism, but specific adaptations linked to the coral’s antioxidant capacity drive differences in the sensitivity and thus tolerance of each coral species to thermal stress.
  相似文献   
993.
994.

Background

Video-assisted thoracic surgery (VATS) plays an important role in thoracic surgery because it is less invasive. However, the existence of severe pleural adhesions may make VATS difficult and complicated. The aim of this study was to assess the utility of inspiration and expiration computed tomography (respiratory dynamic CT (RD-CT)) in evaluation of pleural adhesions preoperatively.

Methods

RD-CT was performed on 107 patients undergoing thoracotomies (both VATS and open). We assessed synchronous motion during respiration on RD-CT. Comparing the results of RD-CT and intraoperative findings, we assessed the utility of preoperative evaluation.

Results

A negative correlation between sliding score and adhesion grade was revealed. Sliding score in adhesion negative patients was significantly higher than that in adhesion positive patients (P?<?0.0001). The sensitivity of RD-CT was 63.6%, specificity was 74.1%, and accuracy was 72%. Among 62 patients with a CT-Respiration Ratio of less than 0.65, the sensitivity of RD-CT was 77.8%, specificity was 86.8%, and accuracy was 85.5%.

Conclusions

RD-CT may be clinically useful for detecting the presence of pleural adhesions. It can be adopted as one of the criteria for deciding the surgical approach.
  相似文献   
995.

Background

Spontaneous isolated dissection of the superior mesenteric artery (SMA) can lead to bowel ischemia, aneurysm rupture, or even death. Studies have suggested that mechanical or hemodynamic stress on the vascular wall of the SMA may be a contributor, but its pathogenesis is unclear.

Case presentation

A 57-year-old Japanese man with a history of untreated hypertension and hyperuricemia was admitted to our hospital with the sudden onset of severe epigastric pain. Laboratory findings showed elevated white blood cell count and C-reactive protein, and contrast-enhanced computed tomography (CT) of the abdomen demonstrated arterial dissection with luminal stenosis and aneurysm formation at the distal portion of the SMA after the branching of the jejunal artery, and intravenous nicardipine was administered. The patient’s epigastric pain resolved spontaneously but recurred on day 6 of his hospital stay. Contrast-enhanced abdominal CT revealed an enlarged aneurysm with wall thinning. Because of the risk of aneurysm rupture, the decision was made to perform aneurysmectomy and bowel resection on day 6. Histologic examinations revealed two separate dissecting lesions: one latent and the other resulting in aneurysm formation. Both lesions showed characteristics of segmental arterial mediolysis (SAM) with lack of arterial media, absence of internal and external elastic laminae and intimal proliferation.

Conclusions

Histologic findings in the present case suggest that mechanical or hemodynamic stress on the vascular wall and SAM-related vascular vulnerability may concomitantly contribute to the onset of isolated SMA dissection.
  相似文献   
996.

Background

EPH (erythropoietin-producing hepatocellular) receptors are clinically relevant targets in several malignancies. This report describes the effects of GLPG1790, a new potent pan-EPH inhibitor, in human embryonal rhabdomyosarcoma (ERMS) cell lines.

Methods

EPH-A2 and Ephrin-A1 mRNA expression was quantified by real-time PCR in 14 ERMS tumour samples and in normal skeletal muscle (NSM). GLPG1790 effects were tested in RD and TE671 cell lines, two in vitro models of ERMS, by performing flow cytometry analysis, Western blotting and immunofluorescence experiments. RNA interfering experiments were performed to assess the role of specific EPH receptors. Radiations were delivered using an x-6 MV photon linear accelerator. GLPG1790 (30 mg/kg) in vivo activity alone or in combination with irradiation (2 Gy) was determined in murine xenografts.

Results

Our study showed, for the first time, a significant upregulation of EPH-A2 receptor and Ephrin-A1 ligand in ERMS primary biopsies in comparison to NSM. GLPG1790 in vitro induced G1-growth arrest as demonstrated by Rb, Cyclin A and Cyclin B1 decrease, as well as by p21 and p27 increment. GLPG1790 reduced migratory capacity and clonogenic potential of ERMS cells, prevented rhabdosphere formation and downregulated CD133, CXCR4 and Nanog stem cell markers. Drug treatment committed ERMS cells towards skeletal muscle differentiation by inducing a myogenic-like phenotype and increasing MYOD1, Myogenin and MyHC levels. Furthermore, GLPG1790 significantly radiosensitized ERMS cells by impairing the DNA double-strand break repair pathway. Silencing of both EPH-A2 and EPH-B2, two receptors preferentially targeted by GLPG1790, closely matched the effects of the EPH pharmacological inhibition. GLPG1790 and radiation combined treatments reduced tumour mass by 83% in mouse TE671 xenografts.

Conclusions

Taken together, our data suggest that altered EPH signalling plays a key role in ERMS development and that its pharmacological inhibition might represent a potential therapeutic strategy to impair stemness and to rescue myogenic program in ERMS cells.
  相似文献   
997.

Background

Malignant ovarian germ cell tumor is a rare type of disease, which generally has a good prognosis due to the high chemosensitivity of this type of tumor.Fertility preservation is an important issue because malignant ovarian germ cell tumor commonly affects young women. Although conservation is the standard for early stage, it becomes more debatable as the disease progresses to more advanced stages.Aim: Report the case of a patient with an International Federation of Gynecology and Obstetrics Stage IIIc malignant ovarian germ cell tumor, who had conservative surgery and chemotherapy with a good fertility outcome.

Case presentation

A 23-year-old North African woman with a left malignant ovarian germ cell tumor stage IIIc was treated by left adnexectomy and omentectomy followed by chemotherapy. A 15-year follow-up showed no signs of relapse, and she completed three full-term natural pregnancies.

Conclusions

Malignant ovarian germ cell tumor is a rare ovarian tumor with a good prognosis. It is usually associated with a good fertility outcome in early stages. However, due to the rarity of the disease in advanced stages, the fertility outcome for this group of patients is not clear. This lack of data surrounding advanced stages points to the need for a meta-analysis of all published cases.
  相似文献   
998.
Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) is a ladybird native to Australia, preying on mealybugs and soft scales, and has been utilized worldwide as a biological control agent. It has long been recognized that C. montrouzieri that was introduced into the main island of Japan had failed to become established. The present study monitored yearly and seasonal occurrence of C. montrouzieri adults in citrus groves at Shizuoka Prefectural Fruit Tree Research Center in Shizuoka City, central Japan in 2008–2012 by using sticky traps and beating citrus trees. Adults of C. montrouzieri were continuously captured for 5 and 4 years in a pesticide-free citrus grove and a neighboring reduced-pesticide grove, respectively. Larvae of C. montrouzieri were observed consuming a cottony scale, Pulvinaria aurantii Cockerell, on citrus trees. These results provide unequivocal evidence for the ladybird’s establishment in central Japan. The number of trapped ladybird adults exhibited four peaks a year: in mid-April, early to late June, mid-August, and late September to early October. Adult numbers in each grove varied largely across years, showing a great increase followed by a rapid decline during a period of 4 years. Factors affecting the seasonal/yearly occurrence of C. montrouzieri adults in citrus groves are discussed.  相似文献   
999.
Dragonflies are colorful insects, and recent RNA sequencing studies have identified a number of candidate genes potentially involved in their color pattern formation and color vision. However, functional aspects of such genes have not been assessed due to the lack of molecular genetic tools applicable to dragonflies. We established an electroporation-mediated RNA interference (RNAi) procedure using the tiny dragonfly Nannophya pygmaea Rambur, 1842 (Odonata: Libellulidae) that targets the multicopper oxidase 2 gene (MCO2; also known as laccase2 gene) responsible for cuticular pigmentation in many insects. RNA sequencing of N. pygmaea and genomic survey of the dragonfly Ladona fulva identified four multicopper oxidase family genes: MCO1, MCO2, MCO3 and multicopper oxidase-related protein gene (MCORP). In N. pygmaea, MCO2 was specifically expressed around the cuticular pigmentation period, whereas MCO1 was constantly expressed. MCORP was expressed at adult stages, and MCO3 was scarcely expressed. When we applied in vivo electroporation, final instar larvae injected with MCO2 small interfering RNA became adults with patchy unpigmented regions. RNAi without in vivo electroporation did not affect cuticular pigmentation, suggesting that dragonflies do not show a systemic RNAi response. These results indicate that MCO2 is required for cuticular pigmentation across diverse insects, and highlight the usefulness of the electroporation-mediated RNAi method in dragonflies.  相似文献   
1000.
Extraction of DNA from non-invasive samples (feces) has been used increasingly in genetic research on wildlife. For effective and reliable genetic analyses, knowledge about which samples should be selected in the field is essential. For this reason, we examined the process of DNA degradation in feces of deer. We collected fresh fecal pellets from three wild deer living in a warm temperate forest. We then assessed the effects of time (3, 5, and 10 days) under three environmental conditions (on the forest floor, on exposed ground, and inside the laboratory) on the rates of correct genotyping (CG), amplification failure (NA), genotyping error among positive amplification (ER), false alleles (FA), and allelic dropout (AD) of 15 microsatellite loci. The rate of CG significantly decreased, and those of NA and FA increased with increasing lapse of time. Rates of CG tended to be highest and those of NA, ER, FA, and AD to be lowest in feces kept inside, followed by those on the forest floor. Suitability of samples for DNA extraction was lowest in fecal pellets left on exposed ground, and we suspect that rain may hasten DNA degradation. NA rate could serve as a reliable indicator of the quality of fecal pellets because it was significantly positively correlated with ER rate. For efficient genetic analyses using deer feces in warm temperate zones, we recommend collecting fecal pellets within 3 days of defecation, during periods without rainfall and from under the cover of trees.  相似文献   
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