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1.

Background

Class 3 semaphorins are soluble proteins involved in cell adhesion and migration. Semaphorin-3A (Sema3A) was initially shown to be involved in neuronal guidance, and it has also been reported to be associated with immune disorders. Both Sema3A and its receptors are expressed by most immune cells, including monocytes, macrophages, and lymphocytes, and these proteins regulate cell function. Here, we studied the correlation between Sema3A-induced changes in biophysical parameters of thymocytes, and the subsequent repercussions on cell function.

Methods

Thymocytes from mice were treated in vitro with Sema3A for 30 min. Scanning electron microscopy was performed to assess cell morphology. Atomic force microscopy was performed to further evaluate cell morphology, membrane roughness, and elasticity. Flow cytometry and/or fluorescence microscopy were performed to assess the F-actin cytoskeleton and ROCK2. Cell adhesion to a bovine serum albumin substrate and transwell migration assays were used to assess cell migration.

Results

Sema3A induced filopodia formation in thymocytes, increased membrane stiffness and roughness, and caused a cortical distribution of the cytoskeleton without changes in F-actin levels. Sema3A-treated thymocytes showed reduced substrate adhesion and migratory ability, without changes in cell viability. In addition, Sema3A was able to down-regulate ROCK2.

Conclusions

Sema3A promotes cytoskeletal rearrangement, leading to membrane modifications, including increased stiffness and roughness. This effect in turn affects the adhesion and migration of thymocytes, possibly due to a reduction in ROCK2 expression.

General significance

Sema3A treatment impairs thymocyte migration due to biomechanical alterations in cell membranes.  相似文献   

2.

Background

Monolayer cell cultures have been considered the most suitable technique for in vivo cellular experiments. However, a lot of cellular functions and responses that are present in natural tissues are lost in two-dimensional cell cultures. In this context, nanoparticle accumulation data presented in literature are often not accurate enough to predict behavior of nanoparticles in vivo. Cellular spheroids show a higher degree of morphological and functional similarity to the tissues.

Methods

Accumulation and distribution of carboxylated CdSe/ZnS quantum dots (QDs), chosen as model nanoparticles, was investigated in cellular spheroids composed of different phenotype mammalian cells. The findings were compared with the results obtained in in vivo experiments with human tumor xenografts in immunodeficient mice. The diffusive transport model was used for theoretical nanoparticles distribution estimation.

Results

QDs were accumulated only in cells, which were localized in the periphery of cellular spheroids. CdSe/ZnS QDs were shown to be stable and inert; they did not have any side-effects for cellular spheroids formation. Penetration of QDs in both cellular spheroids and in vivo tumor model was limited. The mathematical model confirmed the experimental results: nanoparticles penetrated only 25 μm into cellular spheroids after 24 h of incubation.

Conclusions

Penetration of negatively charged nanoparticles is limited not only in tumor tissue, but also in cellular spheroids.

General Significance

The results presented in this paper show the superior applicability of cellular spheroids to cell monolayers in the studies of the antitumor effect and penetration of nanomedicines.  相似文献   

3.

Aim

To define the optimal margin on MRI scans in the re-radiation planning of recurrent glioblastoma using methionine positron emission tomography (MET-PET).

Background

It would be very useful if the optimal margin on MRI to cover the uptake area on MET-PET is known.

Materials and Methods

CT, MRI, and MET-PET were performed separately over the course of 2 weeks. Among the MRI scans, we used the contrast-enhanced T1-weighted images (Gd-MRI) and T2-weighted images (T2-MRI). The Gd-MRI-based clinical target volume (CTV) (CTV-Gd) and the T2-MRI-based CTV (CTV-T2) were defined as the contrast-enhanced area on Gd-MRI and the high intensity area on T2-MRI, respectively. We defined CTV x mm (x = 5, 10, 15, 20) as x mm outside the CTV. MET-PET-based CTV (CTV-MPET) was defined as the area of accumulation of MET-PET. We calculated the sensitivity and specificity of CTV-Gd and CTV-T2 following comparison with CTV-MPET, which served as the gold standard in this study.

Results

The sensitivity of CTV-T2 5 mm (98%) was significantly higher than CTV-T2 (87%), and there was no significant difference in the sensitivity between CTV-T2 5 mm and CTV T2 10, 15, or 20 mm. The sensitivity of CTV-Gd 20 mm (97%) was lower than that of CTV-T2 5 mm (98%).

Conclusions

A margin of at least 5 mm around the high intensity area on T2-MRI is necessary in the target volume delineation of recurrent glioblastoma for the coverage of MET-PET findings in re-radiation therapy planning.  相似文献   

4.
5.

Background

Tumor microenvironment is composed of a largely altered extracellular matrix with different cell types. The complex interplay between macrophages and tumor cells through several soluble factors and signaling is an important factor in breast cancer progression.

Methods

We have extended our earlier studies on monocyte and macrophage conditioned medium (M?CM) and have carried out proteomic analysis to identify its constituents as well as validation. The 8-gene signature identified through macrophage-breast cancer cell interactions was queried in cBioportal for bioinformatic analyses.

Results

Proteomic analysis (MALDI-TOF and LC-MS/MS) revealed integrin and matrix metalloproteinases in M?CM which activated TGF-β1, IL-6, TGF- βRII and EGFR as well as its downstream STAT and SMAD signaling in breast cancer cells. Neutralization of pro-inflammatory cytokines (TNF-α. Il-1β, IL-6) abrogated the M?CM induced migration but invasion to lesser extent. The 8- gene signature identified by macrophage-tumor interactions (TNF-α, IL-1β, IL-6, MMP1, MMP9, TGF-β1, TGF-βRII, EGFR) significantly co-occurred with TP53 mutation, WTAPP1 deletion and SLC12A5 amplification along with differential expression of PSAT1 and ESR1 at the mRNA level and TPD52and PRKCD at the protein level in TCGA (cBioportal). Together these genes form a novel 15 gene signature which is altered in 63.6% of TCGA (1105 samples) data and was associated with high risk and poor survival (p < 0.05) in many breast cancer datasets (SurvExpress).

Conclusions

These results highlight the importance of macrophage signaling in breast cancer and the prognostic role of the15-gene signature.

General significance

Our study may facilitate novel prognostic markers based on tumor-macrophage interaction.  相似文献   

6.

Background

The current study was designed to investigate the effect of crocetin on the proliferation inhibition of colon cancer cells and the underlying mechanism.

Methods

MTT assay showed inhibition of proliferation of colon cancer cells in a dose based manner by crocetin treatment. At 30 µM concentration of crocetin proliferation rate of colon cancer cells was reduced to 14% after 24 h. Flow cytometry and fluorescence microscopy revealed induction of apoptosis in colon cancer cells on treatment with crocetin. The tube formation was suppressed significantly in the cultures of HUVEC treated with 30 µM concentration of crocetin compared to the control cultures.

Results

The results from transwell assay revealed a significant reduction in the population of DU-145 cells passing through filters of transwell on treatment with crocetin compared to the control cells. Treatment of the DU-145 cells with crocetin caused a significant reduction in the expression levels of NF-κB, VEGF and MMP-9. The results from RT-PCR analysis revealed a significant reduction in the expression of genes involved in inflammation including, HMGB1, IL-6 and IL-8 on treatment of DU-145 cells with crocetin. However, the expression of NAG-1 gene was increased by crocetin treatment in DU-145 cells significantly compared to the control cells.

Conclusion

Crocetin inhibits growth of colon cancer cells and prevents tube formation through induction of apoptosis. Therefore, crocetin can be used efficiently for the treatment of colon cancer.  相似文献   

7.

Background

CDK6 is considered as a highly validated anticancer drug target due to its essential role in regulating cell cycle progression at G1 restriction point. Activation of CDK6 requires the phosphorylation of Thr177 on A-loop, but the structural insights of the activation mechanism remain unclear.

Methods

Herein, all-atoms molecular dynamics (MD) simulations were used to study the effects of Thr177 phosphorylation on the dynamic structure of CDK6-Vcyclin complex.

Results

MD results indicated that the free energy barrier of the transition from open to closed state decreased ~ 47.2% after Thr177 phosphorylation. Key steps along the state transition process were obtained from a cluster analysis. Binding preference of ten different inhibitors to open or closed state were also investigated through molecular docking along with MD simulations methods.

Conclusions

Our results indicated that Thr177 phosphorylation increased the flexibility around the ATP-binding pocket. The transition of the ATP-binding pocket between open and closed states should be considered for understanding the binding of CDK6 inhibitors.

General significance

This work could deepen the understanding of CDKs activation mechanism, and provide useful information for the discovery of new CDKs inhibitors with high affinity and specificity.  相似文献   

8.

Background

Sporotrichosis is a fungal infection caused by the Sporothrix schenckii complex. The adhesion of the fungus to the host tissue has been considered the key step in the colonization and invasion, but little is known about the early events in the host–parasite interaction.

Aims

To evaluate the proteolytic activity of S. schenckii on epithelial cells.

Methods

The proteolytic system (at pH 5 and 7) was evaluated using azocoll and zymograms. The host–parasite interaction and epithelial cell response were also analyzed by examining the microfilament cytoskeleton using phalloidin-FITC and transmission electron microscopy. Finally, the metabolic activity was determined using an XTT assay.

Results

The zymograms showed that S. schenckii yeast cells possess high intracellular and extracellular proteolytic activities (Mr  200, 116, 97, and 70 kDa) that are pH dependent and are inhibited by PMSF and E64, which act on serine and cysteine-type proteases. During the epithelial cell–protease interaction, the cells showed alterations in the microfilament distribution, as well as in the plasma membrane structure. Moreover, the metabolic activity of the epithelial cells decreased 60% without a protease inhibitor.

Conclusions

Our data demonstrate the complexity of the cellular responses during the infection process. This process is somehow counteracted by the action of proteases inhibitors. Furthermore, the results provide critical information for understanding the nature of host–fungus interactions and for searching a new effective antifungal therapy, which includes protease inhibitors.  相似文献   

9.

Objective

Observing the effect of nano-silver hydrogel coating film on deep partial thickness scald model of rabbit.

Method

We prepared boiling water scalded rabbits with deep II degree scald models and applied high, medium and low doses of nano-silver hydrogel coating film for different time and area. Then we compared the difference of burned paper weight before administration and after administration model burns, burn local skin irritation points infection, skin crusting and scabs from the time, and the impact of local skin tissue morphology.

Result

Rabbits deep II degree burn model successful modeling; on day 12, 18, high, medium and low doses of nano-silver hydrogel coating film significantly reduced skin irritation of rabbits infected with the integral value (P < 0.01, P < 0.05); high, medium and low doses of nano-silver hydrogel coating film group significantly decreased skin irritation, infection integral value (P < 0.01, P < 0.05); high, medium and low doses of nano-silver hydrogel coating film significantly reduced film rabbits’ scalded skin crusting time (P < 0.01), significantly shortened the rabbit skin burns from the scab time (P < 0.01), and significantly improved the treatment of skin diseases in rabbits scald model change (P < 0.01, P < 0.05).

Conclusion

The nano-silver hydrogel coating film on the deep partial thickness burns has a significant therapeutic effect; external use has a significant role in wound healing.  相似文献   

10.

Objective

Anti-inflammatory activity of rhein in animal models with potential mechanism of actions.

Methods

Rhein was isolated from Cassia fistula L. flowers collected in Chennai, Tamil Nadu, India. Its anti-inflammatory activity was then investigated in Wistar rats and mice using carrageenan-induced hind paw oedema, croton oil-induced ear oedema, cotton pellet-induced granuloma and acetic acid-induced vascular permeability models.

Results

Administration of rhein (10, 20, 40 mg/kg) significantly (p < 0.05) inhibited carrageenan-induced paw oedema in rats and croton oil-induced ear oedema in mice in dose-dependent manners. Continual administration of rhein to rats using implanted cotton pellets significantly (p < 0.05) reduced granuloma formation (20 mg/kg: 17.24%; 40 mg/kg: 36.12%) compared to control group animals. Administration of rhein increased the activities of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) and decreased the levels of nitrite, interleukin-6 (IL-6), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), malondialdehyde (MDA) and vascular endothelial growth factor (VEGF) compared to control animals. Western blotting results revealed that rhein diminished carrageenan-induced cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) and increased heme oxygenase (HO)-1, nuclear factor erythroid 2–related factor 2 (Nrf2), peroxisome proliferator-activated receptor gamma (PPAR)-γ and heat shock protein (HSP)-72 expression after 6 h in the paw oedema model.

Conclusion

The anti-inflammatory mechanisms of rhein might be related to decrease in the levels of MDA, iNOS and COX-2 and the stimulation of HO-1, PPAR-γ and Nrf2 expression via increases in the activities of CAT, SOD and GSH-px through the suppression of nitrite, TNF-α, IL-6 and IL-1β.  相似文献   

11.

Background

Fatigue is a sensation of unbearable tiredness that frequently accompanies chronic widespread musculoskeletal pain (CWP) and inflammatory joint disease. Its mechanisms are poorly understood and there is a lack of effective biomarkers for diagnosis and onset prediction. We studied the circulating metabolome in a population sample characterised for CWP to identify biomarkers showing specificity for fatigue.

Material and methods

Untargeted metabolomic profiling was conducted on fasting plasma and serum samples of 1106 females with and without CWP from the TwinsUK cohort. Linear mixed-effects models accounting for covariates were used to determine relationships between fatigue and metabolites. Receiver operating curve (ROC)-analysis was used to determine predictive value of metabolites for fatigue.

Results

While no association between fatigue and metabolites was identified in twins without CWP (n = 711), in participants with CWP (n = 395), levels of eicosapentaenoate (EPA) ω-3 fatty acid were significantly reduced in those with fatigue (β = ? 0.452 ± 0.116; p = 1.2 × 10? 4). A significant association between fatigue and two other metabolites also emerged when BMI was excluded from the model: 3-carboxy-4-methyl-5-propyl-2-furanpropanoate (CMPF), and C-glycosyltryptophan (p = 1.5 × 10? 4 and p = 3.1 × 10? 4, respectively). ROC analysis has identified a combination of 15 circulating metabolites with good predictive potential for fatigue in CWP (AUC = 75%; 95% CI 69–80%).

Conclusion

The results of this agnostic metabolomics screening show that fatigue is metabolically distinct from CWP, and is associated with a decrease in circulating levels of EPA. Our panel of circulating metabolites provides the starting point for a diagnostic test for fatigue in CWP.  相似文献   

12.

Introduction

Progress in understanding pathophysiological mechanisms and the development of targeted regenerative strategies have been hampered by the lack of predictive disease models, specifically for the conditions to which affected cell types are inaccessible. The present study has aimed to unearth the role of valproic acid (VPA) and mild hypothermia (MH) as promising strategy to enhance the neuroprotective mechanisms in undifferentiated and differentiated human neural precursor cells (hNPCs) against ethanol-induced damage.

Methods

5 mM VPA alone or in combination with MH (33 °C) was used to prevent the damage in proliferating and differentiating hNPCs. CD133 + ve enriched hNPCs were cultured in vitro and exposed to 1 M chronic ethanol concentration for 72 h and followed by VPA and MH treatment for 24 h. Morphometric analysis was performed to identify changes in neurospheres development and neuronal cell phenotypes. Flow cytometry and RT-qPCR analysis was performed to investigate alterations in key molecular pathways involved in cell survival and signaling.

Results

Combination of VPA with MH displayed higher proportion of neuronal cell viability as compared to single treatment. Combination treatment was most effective in reducing apoptosis and reactive oxygen species levels in both the undifferentiated and differentiated hNPCs. VPA with MH significantly improved neuronal cell phenotype, active chromatin modeling, chaperon and multi-drug resistant pumps activity and expression of neuronal signaling molecules.

Conclusion

The study provided an efficient and disease specific in vitro model and demonstrated that combined treatment with VPA and MH activates several neuroprotective mechanisms and provides enhanced protection against ethanol-induced damage in cultured undifferentiated and differentiated hNPCs.  相似文献   

13.

Background

V-ATPase interactions with cholesterol enriched membrane microdomains have been related to metastasis in a variety of cancers, but the underlying mechanism remains at its beginnings. It has recently been reported that the inhibition of this H+ pump affects cholesterol mobilization to the plasma membrane.

Methods

Inhibition of melanoma cell migration and invasiveness was assessed by wound healing and Transwell assays in murine cell lines (B16F10 and Melan-A). V-ATPase activity was measured in vitro by ATP hydrolysis and H+ transport in membrane vesicles, and intact cell H+ fluxes were measured by using a non-invasive Scanning Ion-selective Electrode Technique (SIET).

Results

Cholesterol depletion by 5 mM MβCD was found to be inhibitory to the hydrolytic and H+ pumping activities of the V-ATPase of melanoma cell lines, as well as to the migration and invasiveness capacities of these cells. Nearly the same effects were obtained using concanamycin A, a specific inhibitor of V-ATPase, which also promoted a decrease of the H+ efflux in live cells at the same extent of MβCD.

Conclusions

We found that cholesterol depletion significantly affects the V-ATPase activity and the initial metastatic processes following a profile similar to those observed in the presence of the V-ATPase specific inhibitor, concanamycin.

General significance

The results shed new light on the functional role of the interactions between V-ATPases and cholesterol-enriched microdomains of cell membranes that contribute with malignant phenotypes in melanoma.  相似文献   

14.

Aim

The purpose of the study was to publish our experience of salivary gland cancer treatment with large number of patients treated at a single institution.

Background

Salivary gland cancers are rare tumors of the head and neck representing about 5% of cancers in that region and about 0.5% of all malignancies. Due to the rarity of the disease, most of the studies regarding treatment outcome consist of low number of patients, thus making it difficult to draw conclusions.

Material and methods

115 patients with primary salivary gland cancer were included in a retrospective study. The subsites of tumor were the parotid gland (58% patients), submandibular gland (19%) and minor salivary glands (23%). All patients underwent primary surgical resection. The following were collected: age, stage of the disease, T status, N status, grade of tumor, perineurial invasion, lymphovascular invasion, extracapsular spread, final histological margin status and postoperative treatment. Details of local, regional or distant recurrence, disease free survival and overall survival were included.

Results

The majority (65%) of patients presented in early stage, T1 and T2 tumors. 81% of patients were N0. Free surgical margins were achieved in 18% of patients, close in 28% patients and positive surgical margins in 54% (62) patients. Factors that significantly increased the risk of recurrence: T stage (p = 0.0006); N-positive status (p < 0.0001); advanced stage of the disease (p < 0.0001); high grade of tumor (p = 0.0007); PNI (p = 0.0061); LVI (p = 0.0022); ECS (p = 0.0136); positive surgical margins (p = 0.0022). On multivariate analysis, high grade of tumor and positive surgical margins remained significant independent adverse factors for recurrence formation.

Conclusions

This report shows a single institution results of oncological treatment in patients with malignant salivary gland tumors, where positive surgical margins strongly correlate with patients’ worse outcome. Whether to extend the procedure, which very often requires sacrificing the nerve is still a question of debate.  相似文献   

15.

Introduction

Endotoxins, in the form of lipopolysaccharides (LPS), are potent inducers of biliary injury. However the mechanism by which injury develops remains unclear. We hypothesized that hepatic macrophages are pivotal in the development of endotoxin-induced biliary injury and that no injury would occur in their absence.

Material and methods

Clodronate liposomes were used to deplete macrophages from the liver. Forty-eight rats were equally divided across six study groups: sham operation (sham), liposome treatment and sham operation (liposomes + sham), 1 mg/kg LPS i.p. (LPS), liposome treatment and LPS administration (liposomes + LPS), hepatic ischaemia-reperfusion injury with LPS administration (IRI + LPS) and liposome treatment followed by IRI + LPS (liposomes + IRI + LPS). Following 6 h of reperfusion, blood, bile, and liver tissue was collected for further analysis. Small bile duct injury was assessed, serum liver tests were performed and bile composition was evaluated. The permeability of the blood-biliary barrier (BBB) was assessed using intravenously administered horseradish peroxidase (HRP).

Results

The presence of hepatic macrophages was reduced by 90% in LPS and IRI + LPS groups pre-treated with clodronate liposomes (P < 0.001). Severe small bile duct injury was not affected by macrophage depletion, and persisted in the liposomes + IRI + LPS group (50% of animals) and liposomes + LPS group (75% of animals). Likewise, BBB impairment persisted following macrophage depletion. LPS-induced elevation of the chemokine Mcp-1 in bile was not affected by macrophage depletion.

Conclusions

Depletion of hepatic macrophages did not prevent development of biliary injury following LPS or LPS-enhanced IRI. Cholangiocyte activation rather than macrophage activation may underlie this injury. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.  相似文献   

16.

Objective

The present study aimed at evaluating the efficacy of an improved phage lysate marker vaccine for haemorrhagic septicaemia in mice and rabbit model and development of a DIVA ELISA based on iron restricted outer membrane protein (IROMP).

Method

The experimental vaccine was prepared by lysing P. multocida B:2 grown under iron restricted conditions with a Pasteurella bacteriophage and addition of an alum adjuvant to enhance the immunogenicity. The vaccine was administered in mice and rabbits divided into two group each. Phage lysate vaccine (PL-VacI) was administered to group I mice and rabbits whereas group II mice and rabbits received alum precipitated HS vaccine (HS-VacII). Antibody titres were monitored 0, 30, 60, 90, 210 and 240 dpv. An IROMP (130 kDa) based indirect ELISA was also developed to differentiate between infected and vaccinated animals. The Pasteurella phage isolated in present study was sequenced at Georgia Genomic Facilty, Georgia.

Result

The sequence of PMP-GAD-IND (Pasteurella bacteriophage) was deposited in GenBank under no KY203335. The group I mice and rabbits vaccinated with Phage lysate vaccine (PL-VacI) group revealed significantly higher antibody titres than group II mice and rabbits receiving alum-precipitated bacterin (HS-VacII) by MAT, IHA and ELISA (P < 0.05 and P < 0.001). The peak log 10 values (3.46) in case of group I mice by ELISA were attained at 90DPI whereas in group II mice the peak values at 90DPI were 2.82. Mean log10 titres by ELISA in group I and II rabbits were 2.43 and 2.35 respectively at 30DPI whereas at 120DPI the titres were 3.29 and 2.75, respectively. The DIVA ELISA detected presence of a novel 137 kDa IROMP/siderophore antibody in sera of group I mice and rabbits (PL-VacI) absent in sera of mice and rabbits given HS-VacII.

Conclusion

The bacteriophage based marker vaccine (PL-VacI) had a more effective and longer immune response against HS in mice and rabbit in comparison to the widely used alum precipitated HS vaccine (HS-VacII). Moreover, the development of a recombinant IROMP based indirect ELISA could serve as an excellent tool to differentiate between infected and vaccinated cattle and buffaloes for effective control of HS.  相似文献   

17.

Background

Invasive candidiasis by Candida albicans is associated with high morbidity and mortality, due in part to the late implementation of an appropriate antifungal therapy hindered by the lack of an early diagnosis.

Aims

We aimed to evaluate the in vitro antifungal activity of the antibodies against C. albicans germ tubes (CAGTA) raised in a rabbit model of candidemia.

Methods

We measured the effect of CAGTA activity by colorimetric XTT and crystal violet assays, and colony forming units count, both on C. albicans planktonic cells and during the course of biofilm formation and maturation. Viability and cell morphology were assessed by optical, fluorescent or scanning electron microscopy.

Results

CAGTA ≥50 μg/ml caused a strong inhibition of C. albicans blastospores growth, and DiBAC fluorescent staining evidenced a fungicidal activity. Moreover, electron microscopy images revealed that CAGTA induced morphological alterations of the surface of C. albicans germ tubes grown free as well as in biofilm. Interestingly, CAGTA ≥80 μg/ml reduced the amount of C. albicans biofilm, and this effect started at the initial adhesion stage of the biofilm formation, during the first 90 min.

Conclusions

This is the first report showing that CAGTA reduce C. albicans growth, and impair its metabolic activity and ability to form biofilm in vitro. The antigens recognized by CAGTA could be the basis for the development of immunization protocols that might protect against Candida infections.  相似文献   

18.

Background

The wastes of pecan nut (Carya illinoinensis (Wangenh.) K. Koch) production are increasing worldwide and have high concentrations of tannins and phenols.

Aims

To study the biodegradation of lignocellulosic wastes of pecan used as solid substrate for the cultivation of the white-rot fungus Ganoderma lucidum (Curtis) P. Karst.

Methods

Six formulations of pecan wastes were used as solid substrate: pecan shells (PS100), pecan pericarp (PP100), pecan wood-chips (PB100), and the combinations PS50 + PP50, PB50 + PS50 and PB50 + PP50. The substrates were inoculated with a wild strain of G. lucidum collected in the Iberian Peninsula. The biodegradation capability of G. lucidum was estimated by using the mycelial growth rate, the biological efficiency, the production and the dry biological efficiency.

Results

Notably, all solid substrates were suitable for G. lucidum growth and mushroom yield. The best performance in mushroom yield was obtained with PB100 (55.4% BE), followed by PB50 + PP50 (31.7% BE) and PB50 + PS50 (25.4% BE). The mushroom yield in the substrates containing pecan wood-chips (PB) was significantly higher.

Conclusions

Our study is leading the way in attempting the cultivation of G. lucidum on lignocellulosic pecan waste. These results show an environmentally friendly alternative that increases the benefits for the global pecan industry, especially in rural areas, and transforms biomass into mushrooms with nutraceutical properties and biotechnological applications.  相似文献   

19.

Aim

In this study, at different fields, energies and gantry angles, treatment couch and rails dose absorption ratio and treatment couch effect on surface and build-up region doses were examined.

Background

It is assumed that radiation attenuation is minimal because the carbon fiber couches have low density and it is not generally accounted for during treatment planning. Consequently, it leads to a major dosimetric mistake.

Materials and methods

Solid water phantom was used for relative dose measurement. The measurements were done using a Farmer ion chamber with 0.6 cc volume and a parallel plane ion chamber starting from surface with 1 mm depth intervals at 10 × 10 cm2 field, SSD 100 cm. Measurements were taken for situations where the beams intersect the couch and couch rails.

Results

Dose absorption ratio of carbon fiber couch obtained at gantry angle of 180° was 1.52%, 0.69%, 0.33% and 0.25% at different field sizes for 6 MV. For 15 MV, this ratio was 0.95%, 0.27%, 0.20% and 0.05%. The absorption ratio is between 3.4% and 1.22% when the beams intersect with couch rails. The couch effect increased surface dose from 14% to 70% for 6 MV and from 11.34% to 53.03% for 15 MV.

Conclusions

The results showed that the carbon fiber couch increased surface dose during posterior irradiation. Therefore, the skin-sparing effect of the high energy beams was decreased. If the effect of couch is not considered, it may cause significant differences at dose which reaches the patient and may cause tissue problems such as erythema.  相似文献   

20.

Aim

To evaluate the dose distribution to the left anterior descending (LAD) coronary artery in patients treated with postoperative three-dimensional conformal radiotherapy (3DCRT).

Background

Postoperative radiotherapy may increase the risk of heart disease, particularly in patients with left-sided breast cancer. Clinical data on doses to the LAD are limited.

Materials and methods

Retrospective study of 14 patients who underwent postoperative 3DCRT for left breast cancer in 2014. All data were retrieved from medical records. Means, medians, ranges, and percentages were calculated.

Results

The mean dose to the LAD in patients with V25 < 1% was 0.12 cGy. Dmean, Dmax and V25 to the heart were, respectively, 3.7 Gy (range, 0.9–4.18), 40.3 Gy (9.28–62.9), and 1.59 cGy. The mean Dmean and Dmax values in the sample were 9.71 Gy and 33.2 Gy, respectively. The maximum dose to the LAD (D2%) ranged from 3.66 to 53.01 Gy. Due to the spacing of the CT slices (5 mm), it was not possible to completely contour the entire artery. The mean dose to the heart (3.3 Gy) was considered acceptable.

Conclusions

The maximum dose to the LAD was as high as 53 Gy, suggesting an increased risk of cardiac morbidity. This study underscores the value of contouring the LAD and the value of the breath hold technique to reduce maximum cardiac doses. Smaller CT cuts (2.5 mm) can improve contouring. Larger studies with long-term follow up are needed to determine the radiation tolerance dose for the LAD.  相似文献   

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