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41.
Understanding what maintains species and perpetuates their coexistence in a network of feeding relationships (the food web) is of great importance for biodiversity conservation. A food web can be viewed as consisting of a number of simple subunits called trophic modules. Intraguild predation (IGP), in which a prey and its predator compete for the same resource, is one of the best-studied trophic modules. According to theory, there are two ways to yield a large persistent system from such modules: (i) to use persistent subunits as building blocks or (ii) to arrange the subunits in a way that externally supports the nonpersistent subunits. Here, I show that the complex food web of the Caribbean marine ecosystem is constructed in both ways. I show that IGP modules, which convey internal persistence because of the fact that prey are superior competitors for the resources, are overrepresented in the Caribbean ecosystem. The other modules, consisting of competitively inferior prey, are not persistent in isolation. However, competitively inferior prey in these modules tend to receive more advantage from extra-module interactions, which allows persistence of the IGP module. In addition, those exterior interactions tend to be provided by intrinsically persistent IGP modules to prevent cascading extinction of interacting IGP modules. The food web can be viewed as a set of interacting modules, nonrandomly arranged to enhance the maintenance of biodiversity.  相似文献   
42.
We present the case of an 80-year-old man with a tumor recurrence on his right arm 6 years after initial treatment. The lateral aspect of the elbow joint, involving overlaying skin, muscles, tendons, joint capsule, lateral collateral ligament complex, the lateral 1/3 of the capitellum, and lateral epicondyle of humerus were excised in the tumor resection. Intraoperative assessment revealed multidirectional instability of the elbow, and joint stabilization was needed. Because the lateral epicondyle was resected, graft placement in an anatomical position was impossible to carry out. Therefore, non-anatomical reconstruction of lateral ulnar collateral ligament with palmaris longus tendon graft was performed. The skin was reconstructed using an antegrade pedicled radial forearm flap. For wrist extension reconstruction, the pronator quadratus tendon was transferred to the extensor carpi radialis brevis tendon. One year after the operation, elbow range of motion was 5–130°. The patient remains symptom free. The Mayo elbow performance score is good. The Musculoskeletal Tumor Society rating score is excellent. To our knowledge, this is the first report of an elbow lateral ulnar collateral ligament reconstruction after tumor resection.  相似文献   
43.
Inflammation substantially affects the risk of oral malignancy. Pro-inflammatory cytokine, interferon (IFN)-γ, confers anti-tumor activity using several different mechanisms. Conversely, higher expression of interleukin (IL)-17 is associated with worse prognosis. Monocyte chemotactic protein (MCP)-1 correlates positively with poor long-term survival of head and neck squamous cell carcinoma (HNSCC) patients. IL-1α affects cancer associated fibroblasts and macrophages, and promote several malignant phenotypes including immune suppression. Some anti-inflammatory cytokines, including IL-10 and transforming growth factor (TGF)-β, relate to pro-tumoral activities.Among immune checkpoint modulators, programmed death (PD-)1 and PD-ligand (L)1 facilitate oral squamous cell carcinoma (OSCC) cell evasion from immune surveillance, and the expression status of these has a prognostic value.OSCCs contain tumor associated macrophages (TAMs) as major stromal cells of their tumor microenvironment. Among the two distinctive states, M2 macrophages support tumor invasion, metastasis and immune suppression. Crosstalk between TAMs and OSCC or cancer-associated fibroblasts (CAF) plays an important role in the progression of OSCC.Clinical trials with blocking antibodies against IL-1α or melanoma-associated antigens have been reported as therapeutic approaches against OSCCs. The most promising approach activating antitumor immunity is the blockade of PD-1/PD-L1 axis. Manipulating the polarization of pro-tumorigenic macrophages has been reported as a novel therapeutic approach.  相似文献   
44.
Although fibrin sealant (FS) has an advantage of high biocompatibility, its adhesive force and sealing effect have been generally considered to be inadequate. In the present study, a high adhesive force and sealing effect were obtained by first rubbing fibrinogen solution into the target tissue, attaching polyglycolic acid (PGA) felt to the treated area, and finally spraying it with FS. This method was compared with three conventional FS application methods and a method using fibrin glue-coated collagen fleece. The adhesive force resulting from the present method was 12 times higher than that for the sequential application method, 4.5 times higher than the spray method, 2.5 times higher than the rubbing and spray method, and 2.2 times higher than the use of fibrin glue-coated collagen fleece. The high adhesive force of FS with PGA felt seemed to be due the high fibrin content of the fibrin gel (FG). Light and electron microscopic observations suggested that the formation of FG in closer contact with the muscle fibers was a factor contributing to this superior adhesive force. Comparison of the sealing effect of the present method with other methods using various biomaterials in combination with FS showed that the sealing effect of FS with PGA felt was 1.4 times higher that of polyglactin 910, 1.8 times that of polytetrafluoroethylene, and 6.7 times that of oxidized regenerated cellulose.  相似文献   
45.
ObjectivesPrevious reports have associated salivary β-galactosidase activity with non-periodontopathic oral malodour. In this study, we investigated the localization of β-galactosidase and elucidated the relationship between its enzymatic activity and physiological oral malodour.Study designFifty-six patients complaining of halitosis were separated into two groups: periodontally healthy and periodontitis. Saliva samples from the subjects were separated by centrifugation, and the level of β-galactosidase activity was measured in the supernatant, pellet lysate, and whole saliva using the chromogenic substrate o-nitrophenyl-β-d-galactopyranoside. The correlation of salivary β-galactosidase activity with breath odour and associated parameters was examined.ResultsSimilar levels of β-galactosidase activity were detected in the pellet lysate and whole saliva, but not in the saliva supernatant. Positive correlations were observed between the β-galactosidase activity in whole saliva and oral malodour levels in the periodontally healthy group, but not in the periodontitis group. In addition, the plaque index and tongue coating score were positively correlated with β-galactosidase activity in the periodontally healthy group. Overall, stimulated salivary flow and salivary pH were negatively correlated with enzyme activity. The amounts of total bacteria, Fusobacterium nucleatum, and Streptococcus salivarius were positively associated with β-galactosidase activity in the periodontally healthy group. Furthermore, the amounts of total bacteria and S. salivarius were positively associated with the amount of volatile sulphur compounds.ConclusionsOur results indicate that β-galactosidase is located on the cell surface of oral bacteria derived from dental plaque and tongue coating, and it plays an important role in producing the malodour underlying physiological oral malodour.  相似文献   
46.
We describe a rare case of takotsubo cardiomyopathy complicated by acute ventricular septal perforation with ventricular septal dissection. The ventricular perforation was successfully closed by repairing the dissecting site with a bovine pericardial patch. doi: 10.1111/jocs.12676 (J Card Surg 2016;31:150–153)  相似文献   
47.

Purpose

Solute carrier SLC22A4 encodes the carnitine/organic cation transporter OCTN1 and is associated with inflammatory bowel disease, although little is known about how this gene is linked to pathogenesis. The aim of the present study was to identify endogenous substrates that are associated with gastrointestinal inflammation.

Methods

HEK293/OCTN1 and mock cells were incubated with colon extracts isolated from dextran sodium sulfate-induced colitis mice; the subsequent cell lysates were mixed with the amino group selective reagent 3-aminopyridyl-N-hydroxysuccinimidyl carbamate (APDS), to selectively label OCTN1 substrates. Precursor ion scanning against the fragment ion of APDS was then used to identify candidate OCTN1 substrates.

Results

Over 10,000 peaks were detected by precursor ion scanning; m/z 342 had a higher signal in HEK293/OCTN1 compared to mock cells. This peak was detected as a divalent ion that contained four APDS-derived fragments and was identified as spermine. Spermine concentration in peripheral blood mononuclear cells from octn1 gene knockout mice (octn1?/?) was significantly lower than in wild-type mice. Lipopolysaccharide-induced gene expression of inflammatory cytokines in peritoneal macrophages from octn1?/? mice was lower than in wild-type mice.

Conclusions

The combination metabolomics approach can provide a novel tool to identify endogenous substrates of OCTN1.
  相似文献   
48.
49.

Background

Genetic polymorphisms near Interleukin 28B (IL28B) (rs8099917) and a rapid virological response (RVR) have been reported as predictors for a sustained virological response (SVR) to telaprevir (TVR)-based triple combination therapy. However, the association between SVR and viral kinetics earlier than week 4 after initiation of therapy remains unclear. Thus, we evaluated the SVR prediction ability of baseline factors and reduced hepatitis C virus (HCV) RNA levels at week 1 after the initiation of TVR-based therapy in Japanese genotype-1b chronic hepatitis C (CHC) patients.

Methods

A total of 156 Japanese CHC patients received a 24-week regimen of TVR-based therapy. Baseline factors and reduction in HCV RNA levels at weeks 1 and 4 after the initiation of therapy were analyzed for SVR prediction.

Results

Multiple logistic regression analysis for SVR in TVR-based therapy identified the IL28B TT genotype, a reduction of ≥4.7 log10IU/mL in HCV RNA levels at week 1, RVR, and treatment-naïve/relapse. Whereas the SVR rate was higher than 90 % regardless of the reduction in HCV RNA levels at week 1 in patients with the TT genotype, a reduction of ≥4.7 log10IU/mL in HCV RNA levels at week 1 was the strongest predictor of SVR in patients with the non-TT genotype, as determined by multiple logistic regression analysis (P = 0.0043).

Conclusions

The IL28B TT genotype is the most important baseline factor for predicting SVR, and a ≥4.7 log10IU/mL reduction in HCV RNA at week 1 is a useful very early on-treatment predictor of SVR, especially in the non-TT genotype.  相似文献   
50.
A 15‐yr‐old boy presented with an anterior mediastinal mass, multiple lung metastases and obstruction of the left brachiocephalic vein, the superior vena cava and the subclavian vein. Tumor biopsy by CT guidance confirmed a diagnosis of GCT. Five courses of BEP therapy were performed, and CT of the chest revealed reduction in the anterior mediastinal mass and disappearance of the multiple lung metastases. We performed the anterior mediastinal mass extraction followed by adjuvant chemotherapy consisting of ICE and TIP. However, the AFP levels became elevated soon after. Abnormal accumulation was observed in the right upper lung by DW‐MRI. After the operation, two courses of TI chemotherapy and two courses of HDCT followed by auto‐PBSCT were performed. He was complicated with auditory disorder and renal dysfunction. Although HDCT followed by auto‐PBSCT was effective for the relapsed primary mediastinal GCT, a treatment strategy avoiding late complications is warranted.  相似文献   
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