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1.
Sensors (Basel) ; 21(6)2021 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-33799412

RESUMO

A new method for the detection of important scenes in baseball videos via a time-lag-aware multimodal variational autoencoder (Tl-MVAE) is presented in this paper. Tl-MVAE estimates latent features calculated from tweet, video, and audio features extracted from tweets and videos. Then, important scenes are detected by estimating the probability of the scene being important from estimated latent features. It should be noted that there exist time-lags between tweets posted by users and videos. To consider the time-lags between tweet features and other features calculated from corresponding multiple previous events, the feature transformation based on feature correlation considering such time-lags is newly introduced to the encoder in MVAE in the proposed method. This is the biggest contribution of the Tl-MVAE. Experimental results obtained from actual baseball videos and their corresponding tweets show the effectiveness of the proposed method.

2.
Sensors (Basel) ; 21(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809765

RESUMO

A method for prediction of properties of rubber materials utilizing electron microscope images of internal structures taken under multiple conditions is presented in this paper. Electron microscope images of rubber materials are taken under several conditions, and effective conditions for the prediction of properties are different for each rubber material. Novel approaches for the selection and integration of reliable prediction results are used in the proposed method. The proposed method enables selection of reliable results based on prediction intervals that can be derived by the predictors that are each constructed from electron microscope images taken under each condition. By monitoring the relationship between prediction results and prediction intervals derived from the corresponding predictors, it can be determined whether the target prediction results are reliable. Furthermore, the proposed method integrates the selected reliable results based on Dempster-Shafer (DS) evidence theory, and this integration result is regarded as a final prediction result. The DS evidence theory enables integration of multiple prediction results, even if the results are obtained from different imaging conditions. This means that integration can even be realized if electron microscope images of each material are taken under different conditions and even if these conditions are different for target materials. This nonconventional approach is suitable for our application, i.e., property prediction. Experiments on rubber material data showed that the evaluation index mean absolute percent error (MAPE) was under 10% by the proposed method. The performance of the proposed method outperformed conventional comparative property estimation methods. Consequently, the proposed method can realize accurate prediction of the properties with consideration of the characteristic of electron microscope images described above.

3.
Materials (Basel) ; 14(5)2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33800383

RESUMO

Polymethylmethacrylate (PMMA)-based acrylic bone cement is commonly used to fix bone and metallic implants in orthopedic procedures. The polymerization initiator tri-n-butylborane (TBB) has been reported to significantly reduce the cytotoxicity of PMMA-based bone cement compared to benzoyl peroxide (BPO). However, it is unknown whether this benefit is temporary or long-lasting, which is important to establish given that bone cement is expected to remain in situ permanently. Here, we compared the biocompatibility of PMMA-TBB and PMMA-BPO bone cements over several days. Rat femur-derived osteoblasts were seeded onto two commercially-available PMMA-BPO bone cements and experimental PMMA-TBB polymerized for one day, three days, or seven days. Significantly more cells attached to PMMA-TBB bone cement during the initial stages of culture than on both PMMA-BPO cements, regardless of the age of the materials. Proliferative activity and differentiation markers including alkaline phosphatase production, calcium deposition, and osteogenic gene expression were consistently and considerably higher in cells grown on PMMA-TBB than on PMMA-BPO, regardless of cement age. Although osteoblastic phenotypes were more favorable on older specimens for all three cement types, biocompatibility increased between three-day-old and seven-day-old PMMA-BPO specimens, and between one-day-old and three-day-old PMMA-TBB specimens. PMMA-BPO materials produced more free radicals than PMMA-TBB regardless of the age of the material. These data suggest that PMMA-TBB maintains superior biocompatibility over PMMA-BPO bone cements over prolonged periods of at least seven days post-polymerization. This superior biocompatibility can be ascribed to both low baseline cytotoxicity and a further rapid reduction in cytotoxicity, representing a new biological advantage of PMMA-TBB as a novel bone cement material.

4.
EJNMMI Res ; 11(1): 10, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33492478

RESUMO

BACKGROUND: To improve the diagnostic accuracy of axillary lymph node (LN) metastasis in breast cancer patients using 2-[18F]FDG-PET/CT, we constructed an artificial intelligence (AI)-assisted diagnosis system that uses deep-learning technologies. MATERIALS AND METHODS: Two clinicians and the new AI system retrospectively analyzed and diagnosed 414 axillae of 407 patients with biopsy-proven breast cancer who had undergone 2-[18F]FDG-PET/CT before a mastectomy or breast-conserving surgery with a sentinel lymph node (LN) biopsy and/or axillary LN dissection. We designed and trained a deep 3D convolutional neural network (CNN) as the AI model. The diagnoses from the clinicians were blended with the diagnoses from the AI model to improve the diagnostic accuracy. RESULTS: Although the AI model did not outperform the clinicians, the diagnostic accuracies of the clinicians were considerably improved by collaborating with the AI model: the two clinicians' sensitivities of 59.8% and 57.4% increased to 68.6% and 64.2%, respectively, whereas the clinicians' specificities of 99.0% and 99.5% remained unchanged. CONCLUSIONS: It is expected that AI using deep-learning technologies will be useful in diagnosing axillary LN metastasis using 2-[18F]FDG-PET/CT. Even if the diagnostic performance of AI is not better than that of clinicians, taking AI diagnoses into consideration may positively impact the overall diagnostic accuracy.

5.
Int Urol Nephrol ; 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33389460

RESUMO

PURPOSE: To evaluate the surgical feasibility and postoperative cosmesis of a novel transumbilical laparoendoscopic single-site (LESS) surgical approach involving Y-shaped incisions and three-flap umbilicoplasty in urachal remnant patients. METHODS: Patients with symptomatic urachal remnants who underwent either conventional laparoscopic surgery (CL group, n = 21) or LESS surgery with Y-shaped incisions and three-flap umbilicoplasty (LESS group, n = 36) between May 2010 and September 2019 were retrospectively assessed. Perioperative factors and postoperative esthetic outcomes were compared between the groups using univariate and multivariate analyses. Esthetic outcomes were assessed using the body image questionnaire consisting of the body image scale (BIS) and the cosmetic scale (CS); a higher score indicated a better outcome. RESULTS: The median operative time was greater and the insufflation time was shorter in the LESS group than in the CL group. The estimated blood loss and postoperative hospital stay and surgical site infection rate did not differ significantly between the groups. While the BIS score also did not differ significantly between the groups, the CS score was greater in the LESS group than in the CL group. Multivariate analysis revealed that the surgery type (LESS surgery) was an independent predictor of greater postoperative esthetic satisfaction. CONCLUSION: Transumbilical LESS surgery with Y-shaped incisions and subsequent three-flap umbilicoplasty is feasible in patients with symptomatic urachal remnants. Regarding postoperative cosmesis, the higher CS score suggests that this technique is superior to CL surgery. Furthermore, the selection of this procedure was an independent predictor of good postoperative esthetic outcomes.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33439769

RESUMO

The aim of this study was to compare the acute cardiometabolic and perceptual responses between local and whole-body passive heating. Using a water-perfused suit, ten recreationally active males underwent three 90 min conditions: heating of the legs with upper-body cooling (LBH), whole-body heating (WBH) and exposure to a thermoneutral temperature (CON). Blood samples were collected before and up to 3h post-session to assess inflammatory markers, while a 2h oral glucose tolerance test was initiated 1h post-session. Femoral artery shear rate and perceptual responses were recorded at regular intervals. The interleukin (IL)-6 incremental area under the curve (iAUC) was higher for LBH (1096±851 pg/mL*270min) and WBH (833±476 pg/mL*270min) compared with CON (565±325 pg/mL*270min; p<0.047). Glucose concentrations were higher after WBH compared with LBH and CON (p<0.046). Femoral artery shear rate was higher at the end of WBH (1713±409 L/min) compared with LBH (943±349 L/min; p<0.001), and higher in LBH than CON (661±222 L/min; p=0.002). Affect and thermal comfort were more negative during WBH compared with LBH and CON (p<0.010). In conclusion, local passive heating elevated shear rate and the IL-6 iAUC. However, while resulting in more positive perceptual responses, the majority of the included cardiometabolic markers were attenuated compared with WBH. The increase in the interleukin-6 incremental area under the curve in response to passive heating is not reduced by upper-body cooling. Novelty: • Upper-body cooling attenuates the plasma nitrite, interleukin-1ra and femoral artery shear rate response to passive heating. • Upper-body cooling leads to more positive perceptual responses to passive heating.

7.
J Endourol ; 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33499743

RESUMO

Background: There is lack of evaluation of the effect of the treated area on the urinary function after focal therapy. The objectives of the study is to evaluate the effects of focal therapy on urinary function in the anterior portion of the transition zone (TZ) with transrectal high-intensity focused ultrasound (HIFU) for localized prostate cancer (PCa). Methods: From 2016 to 2018, patients who were diagnosed as having localized PCa and treated with focal therapy with HIFU, were included prospectively. The urinary function and complications were evaluated separately in the treated regions of the anterior TZ (TZ group) and other portions (other group) for 12 months. Before and after the treatment, the International Prostate Symptom Score (IPSS), IPSS Quality Of Life (QOL), Overactive Bladder Symptom Score (OABSS), and uroflowmetry were evaluated to assess the urinary function. Results: Ninety patients were included in the study. There was no significant differences in the patients' characteristics between the two groups. At 1 month after the treatment, IPSS (p = 0.011), IPSS QOL (p = 0.002), OABSS (p = 0.002), maximum flow rates (p = 0.011), and residual urine volume (p = 0.011) in TZ group were significantly deteriorated compared with the other group. Multivariate logistic regression analysis revealed that anterior TZ treatment (odds ratio, 3.386; p = 0.029) was an independent risk factor for the deterioration with ≥32% of preoperative status of maximum flow rates. Concerning complication, the rates of Grade 2 urinary retention and Grade 3 urethral stricture were 15.4% and 11.5% in the TZ group and 0% and 0% in the other group, respectively. Conclusions: There was a greater risk of urinary dysfunction with treatment in the anterior TZ portion than in the other portion at 1 month after focal therapy with HIFU.

8.
NeuroRehabilitation ; 48(1): 59-66, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33386820

RESUMO

BACKGROUND: The Functional Assessment for Control of Trunk (FACT) was developed to evaluate trunk function after stroke. However, only a few studies used FACT to show functional outcome. OBJECTIVE: This study aimed to validate the FACT predictive ability for functional outcome following stroke and create an English version of the FACT. METHODS: This retrospective, observational study was conducted with patients aged≥65 years with stroke. Patients were divided into two groups according to the median FACT score at admission: trunk impairment or high trunk function group. Multiple regression analysis was performed for Functional Independence Measure (FIM) gain and FIM efficiency to examine the relationship between trunk function assessed by FACT at admission and functional prognosis. RESULTS: 105 participants (mean age, 80.2±7.6, 57.1%were men) were included. Of these, 48 (45.7%) and 57 (54.3%) were categorized to the trunk impairment group and high trunk function group, respectively. FACT score at admission was associated with FIM gain (coefficient = 0.875, P = 0.001) and FIM efficiency (coefficient = 0.015, P = 0.016) after adjusting for confounders. CONCLUSIONS: Trunk impairment at admission assessed by FACT could predict functional prognosis. The English version of FACT was created and further demonstrated the validity of FACT.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33377552

RESUMO

Hydrogen cyanide is an industrially important chemical, and its annual production is more than 1.5 million tons. Because of its toxicity, the cyanide-containing effluents from industries have caused many environmental problems. Among various methods to treat the contaminated soils or water, the biological degradation is regarded to be promising. We isolated two cyanide-degrading microorganisms, Pedobacter sp. EBE-1 and Bacillus sp. EBE-2, from soil contaminated with cyanide. Among these bacteria, Bacillus sp. EBE-2 exhibited significantly a high cyanide-degrading ability. Bacillus sp. EBE-2 might be used for the remediation of cyanide contaminated water or soil. A nitrilase gene was cloned from Bacillus sp. EBE-2. Bacillus nitrilase was expressed in Escherichia coli and purified. Bacillus nitrilase exhibited cyanide-degrading activity as a large oligomer. Since formic acid formation from cyanide was observed, Bacillus nitrilase is likely to be a cyanide hydrolase. Although there exist various homologous enzymes annotated as carbon-nitrogen family hydrolases, this is the first report on the cyanide degrading activity. The structure and catalytic site of Bacillus nitrilase were studied by homology modeling and molecular docking simulation.

10.
Int J Urol ; 27(11): 974-980, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33241599

RESUMO

OBJECTIVE: To evaluate functional outcomes over a year for benign prostatic hyperplasia treated with thulium laser enucleation of the prostate or bipolar transurethral resection of the prostate. METHODS: In this study, we prospectively included 140 patients who were treated for benign prostatic hyperplasia from April 2017 to February 2019. A randomization list was used for non-blind assignment to treatment groups (thulium laser enucleation of the prostate or bipolar transurethral resection of the prostate). The International Prostate Symptom Score, International Prostate Symptom Score quality of life, Overactive Bladder Symptom Score, uroflowmetry and International Index of Erectile Function-5 were used for the assessment of outcomes. Scores were taken before treatment, and at 1, 3, 6, 9 and 12 months after treatment. RESULTS: Preoperatively, characteristics of patients in the thulium laser enucleation of the prostate group (n = 70) and the bipolar transurethral resection of the prostate group (n = 70) did not significantly differ. The thulium laser enucleation of the prostate group had a lower median decrease in hemoglobin (0.10 g/dL vs 0.69 g/dL, P < 0.0001) and shorter median catheterization (2 days vs 3 days, P < 0.0001) than the bipolar transurethral resection of the prostate group. Both groups had significantly improved International Prostate Symptom Score, International Prostate Symptom Score quality of life, Overactive Bladder Symptom Score, maximum flow rate and residual urine compared with preoperative values. In the thulium laser enucleation of the prostate group, erectile function was significantly impaired at 1 month post-treatment compared with pretreatment, but improved to baseline at 3 months; however, the transurethral resection of the prostate group did not recover. However, total energy (P = 0.001) and laser irradiation time (P = 0.025) were significantly different between the patients who had preserved erectile function and those who did not after the treatment in the thulium laser enucleation of the prostate group. CONCLUSIONS: Thulium laser enucleation of the prostate is superior to bipolar transurethral resection of the prostate in resection efficacy, hemostasis, catheterization time and preservation of erectile function. However, excessive laser irradiation time in thulium laser enucleation of the prostate has the possibility to delay improvement of overactive bladder symptoms and decrease sexual function.

11.
Materials (Basel) ; 13(18)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906598

RESUMO

Titanium-based implant abutments and tissue bars are polished during the finalization. We hypothesized that polishing degrades the bioactivity of titanium, and, if this is the case, photofunctionalization-grade UV treatment can alleviate the adverse effect. Three groups of titanium disks were prepared; machined surface, polished surface and polished surface followed by UV treatment (polished/UV surface). Polishing was performed by the sequential use of greenstone and silicon rubber burs. UV treatment was performed using a UV device for 12 min. Hydrophobicity/hydrophilicity was examined by the contact angle of ddH2O. The surface morphology and chemistry of titanium were examined by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. Human epithelium cells were seeded on titanium disks. The number of cells attached, the spreading behavior of cells and the retention on titanium surfaces were examined. The polished surfaces were smooth with only minor scratches, while the machined surfaces showed traces and metal flashes made by machine-turning. The polished surfaces showed a significantly increased percentage of surface carbon compared to machined surfaces. The carbon percentage on polished/UV surfaces was even lower than that on machined surfaces. A silicon element was detected on polished surfaces but not on polished/UV surfaces. Both machined and polished surfaces were hydrophobic, whereas polished/UV surfaces were hydrophilic. The number of attached cells after 24 h of incubation was 60% lower on polished surfaces than on machined surfaces. The number of attached cells on polished/UV surfaces was even higher than that on machined surfaces. The size and perimeter of cells, which was significantly reduced on polished surfaces, were fully restored on polished/UV surfaces. The number of cells remained adherent after mechanical detachment was reduced to half on polished surfaces compared to machined surfaces. The number of adherent cells on polished/UV surfaces was two times higher than on machined surfaces. In conclusion, polishing titanium causes chemical contamination, while smoothing its surface significantly compromised the attachment and retention of human epithelial cells. The UV treatment of polished titanium surfaces reversed these adverse effects and even outperformed the inherent bioactivity of the original titanium.

12.
Ann Epidemiol ; 51: 1-6, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32822852

RESUMO

PURPOSE: Although height and body mass index (BMI) are reported to be positively associated with several common cancers, evidence regarding their association with brain tumor risk remains sparse, particularly in Asian populations. In this study, we analyzed the association between height and BMI and brain tumor risk in a Japanese population using a large population-based prospective cohort study. METHODS: A total of 102,925 participants (48,213 men and 54,712 women) enrolled in the Japan Public Health Center-based Prospective Study were followed from baseline, namely 1990 for cohort I and 1993 for cohort II, until 2012. Information on participants' dietary and lifestyle habits, including height and body weight, was collected through survey questionnaires administered at baseline. We used the Cox proportional hazards regression model to estimate hazard ratios and 95% confidence intervals (CIs) for brain tumor incidence, with adjustment for potential confounding variables. RESULTS: During an average follow-up of 18.1 years, 157 (70 men and 87 women) cases of brain tumor were newly diagnosed. BMI showed a statistically insignificant positive association with the risk of brain tumor. In addition, statistically significant positive trends were seen for men and meningioma, with multivariable-adjusted hazard ratios for a BMI of 27.5 to less than 40 versus 18.5 to less than 23 kg per m2 of 2.14 (95% CI = 0.99-4.59) (P = 0.03) and 1.98 (95% CI = 0.84-4.67) (P = 0.046), respectively. In contrast, height showed no clear association with brain tumor risk, overall or in subgroup analysis. CONCLUSIONS: Compared with a BMI of 18 to less than 23.5 kg per m2, a higher BMI was associated with higher risk of brain tumor, particularly in men and with meningioma.

13.
World J Gastroenterol ; 26(25): 3650-3659, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32742133

RESUMO

BACKGROUND: The risk of gastric cancer increases in patients with Helicobacter pylori-associated chronic atrophic gastritis (CAG). X-ray examination can evaluate the condition of the stomach, and it can be used for gastric cancer mass screening. However, skilled doctors for interpretation of X-ray examination are decreasing due to the diverse of inspections. AIM: To evaluate the effectiveness of stomach regions that are automatically estimated by a deep learning-based model for CAG detection. METHODS: We used 815 gastric X-ray images (GXIs) obtained from 815 subjects. The ground truth of this study was the diagnostic results in X-ray and endoscopic examinations. For a part of GXIs for training, the stomach regions are manually annotated. A model for automatic estimation of the stomach regions is trained with the GXIs. For the rest of them, the stomach regions are automatically estimated. Finally, a model for automatic CAG detection is trained with all GXIs for training. RESULTS: In the case that the stomach regions were manually annotated for only 10 GXIs and 30 GXIs, the harmonic mean of sensitivity and specificity of CAG detection were 0.955 ± 0.002 and 0.963 ± 0.004, respectively. CONCLUSION: By estimating stomach regions automatically, our method contributes to the reduction of the workload of manual annotation and the accurate detection of the CAG.

14.
J Clin Med ; 9(9)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847061

RESUMO

Our objective was to evaluate the seven-year results of photofunctionalized implants placed in regular, complex, and cancer-related cases. This study was a prospective, single-center study. Photofunctionalization was performed immediately prior to implantation with Ultraviolet (UV) light for 15 minutes. The success rate of each patient group and the influential factors on implant failure were analyzed. Seventy implants in 16 patients were included. Four implants were left submerged (sleep). The seven-year success rate of 30 implants in regular cases and 21 implants in complex cases was 100%. The success rate of 15 implants in cancer-related cases was 22.2%, in which implants were placed in resection or reconstructed sites with or without pre- or postoperative radiation history. Implant stability quotient (ISQ) values increased at second-stage surgery by 3.2 in regular cases and by 21.9 in complex cases, while it decreased by -3.5 in cancer cases. Multivariate analysis indicated that bone quality, location, and cancer resection significantly influenced implant failure. A very reliable seven-year success rate was obtained by UV-photofunctionalized implants in regular and complex cases, even with significant site-development procedures. However, the success rate in cancer cases was significantly and remarkably lower, suggesting remaining challenges of pathophysiologically compromised conditions, such as bone resection, segmental defect, and radiation.

15.
Comput Biol Med ; 123: 103903, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32658795

RESUMO

AIM: The aim of this study was to determine whether our deep convolutional neural network-based anomaly detection model can distinguish differences in esophagus images and stomach images obtained from gastric X-ray examinations. METHODS: A total of 6012 subjects were analyzed as our study subjects. Since the number of esophagus X-ray images is much smaller than the number of gastric X-ray images taken in X-ray examinations, we took an anomaly detection approach to realize the task of organ classification. We constructed a deep autoencoding gaussian mixture model (DAGMM) with a convolutional autoencoder architecture. The trained model can produce an anomaly score for a given test X-ray image. For comparison, the original DAGMM, AnoGAN, and a One-Class Support Vector Machine (OCSVM) that were trained with features obtained by a pre-trained Inception-v3 network were used. RESULTS: Sensitivity, specificity, and the calculated harmonic mean of the proposed method were 0.956, 0.980, and 0.968, respectively. Those of the original DAGMM were 0.932, 0.883, and 0.907, respectively. Those of AnoGAN were 0.835, 0.833, and 0.834, respectively, and those of OCSVM were 0.932, 0.935, and 0.934, respectively. Experimental results showed the effectiveness of the proposed method for an organ classification task. CONCLUSION: Our deep convolutional neural network-based anomaly detection model has shown the potential for clinical use in organ classification.

16.
Int J Mol Sci ; 21(11)2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32512780

RESUMO

Acrylic bone cement is widely used in orthopedic surgery for treating various conditions of the bone and joints. Bone cement consists of methyl methacrylate (MMA), polymethyl methacrylate (PMMA), and benzoyl peroxide (BPO), functioning as a liquid monomer, solid phase, and polymerization initiator, respectively. However, cell and tissue toxicity caused by bone cement has been a concern. This study aimed to determine the effect of tri-n-butyl borane (TBB) as an initiator on the biocompatibility of bone cement. Rat spine bone marrow-derived osteoblasts were cultured on two commercially available PMMA-BPO bone cements and a PMMA-TBB experimental material. After a 24-h incubation, more cells survived on PMMA-TBB than on PMMA-BPO. Cytomorphometry showed that the area of cell spread was greater on PMMA-TBB than on PMMA-BPO. Analysis of alkaline phosphatase activity, gene expression, and matrix mineralization showed that the osteoblastic differentiation was substantially advanced on the PMMA-TBB. Electron spin resonance (ESR) spectroscopy revealed that polymerization radical production within the PMMA-TBB was 1/15-1/20 of that within the PMMA-BPO. Thus, the use of TBB as an initiator, improved the biocompatibility and physicochemical properties of the PMMA-based material.

17.
Front Plant Sci ; 11: 563, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582226

RESUMO

Magnesium (Mg) is essential for many biological processes in plant cells, and its deficiency causes yield reduction in crop systems. Low Mg status reportedly affects photosynthesis, sucrose partitioning and biomass allocation. However, earlier physiological responses to Mg deficiency are scarcely described. Here, we report that Mg deficiency in Arabidopsis thaliana first modified the mineral profile in mature leaves within 1 or 2 days, then affected sucrose partitioning after 4 days, and net photosynthesis and biomass production after 6 days. The short-term Mg deficiency reduced the contents of phosphorus (P), potassium, manganese, zinc and molybdenum in mature but not in expanding (young) leaves. While P content decreased in mature leaves, P transport from roots to mature leaves was not affected, indicating that Mg deficiency triggered retranslocation of the mineral nutrients from mature leaves. A global transcriptome analysis revealed that Mg deficiency triggered the expression of genes involved in defence response in young leaves.

18.
Environ Sci Technol ; 54(22): 14474-14481, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-32490671

RESUMO

We investigated the potential effects of different land use and other environmental factors on animals living in a contaminated environment. The study site in Kabwe, Zambia, is currently undergoing urban expansion, while lead contamination from former mining activities is still prevalent. We focused on a habitat generalist lizards (Trachylepis wahlbergii). The livers, lungs, blood, and stomach contents of 224 lizards were analyzed for their lead, zinc, cadmium, copper, nickel, and arsenic concentrations. Habitat types were categorized based on vegetation data obtained from satellite images. Multiple regression analysis revealed that land use categories of habitats and three other factors significantly affected lead concentrations in the lizards. Further investigation suggested that the lead concentrations in lizards living in bare fields were higher than expected based on the distance from the contaminant source, while those in lizards living in green fields were lower than expected. In addition, the lead concentration of lungs was higher than that of the liver in 19% of the lizards, implying direct exposure to lead via dust inhalation besides digestive exposure. Since vegetation reduces the production of dust from surface soil, it is plausible that dust from the mine is one of the contamination sources and that vegetation can reduce exposure to this.

19.
Int J Mol Sci ; 21(12)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545509

RESUMO

Titanium materials are essential treatment modalities in the medical field and serve as a tissue engineering scaffold and coating material for medical devices. Thus, there is a significant demand to improve the bioactivity of titanium for therapeutic and experimental purposes. We showed that ultraviolet light (UV)-pre-treatment changed the protein-adsorption ability and subsequent osteoconductivity of titanium. Fibronectin (FN) adsorption on UV-treated titanium was 20% and 30% greater after 1-min and 1-h incubation, respectively, than that of control titanium. After 3-h incubation, FN adsorption on UV-treated titanium remained 30% higher than that on the control. Osteoblasts were cultured on titanium disks after 1-h FN adsorption with or without UV-pre-treatment and on titanium disks without FN adsorption. The number of attached osteoblasts during the early stage of culture was 80% greater on UV-treated and FN-adsorbed (UV/FN) titanium than on FN-adsorbed (FN) titanium; osteoblasts attachment on UV/FN titanium was 2.6- and 2.1-fold greater than that on control- and UV-treated titanium, respectively. The alkaline phosphatase activity of osteoblasts on UV/FN titanium was increased 1.8-, 1.8-, and 2.4-fold compared with that on FN-adsorbed, UV-treated, and control titanium, respectively. The UV/FN implants exhibited 25% and 150% greater in vivo biomechanical strength of bone integration than the FN- and control implants, respectively. Bone morphogenetic protein-2 (BMP-2) adsorption on UV-treated titanium was 4.5-fold greater than that on control titanium after 1-min incubation, resulting in a 4-fold increase in osteoblast attachment. Thus, UV-pre-treatment of titanium accelerated its protein adsorptivity and osteoconductivity, providing a novel strategy for enhancing its bioactivity.

20.
Microbes Environ ; 35(2)2020.
Artigo em Inglês | MEDLINE | ID: mdl-32350165

RESUMO

Carbonyl sulfide (COS) is the most abundant sulfur compound in the atmosphere, and, thus, is important in the global sulfur cycle. Soil is a major sink of atmospheric COS and the numerical distribution of soil microorganisms that degrade COS is indispensable for estimating the COS-degrading potential of soil. However, difficulties are associated with counting COS-degrading microorganisms using culture-dependent approaches, such as the most probable number (MPN) method, because of the chemical hydrolysis of COS by water. We herein developed a two-step MPN method for COS-degrading microorganisms: the first step for chemoorganotrophic growth that supported a sufficient number of cells for COS degradation in the second step. Our new MPN analysis of various environmental samples revealed that the cell density of COS-degrading microorganisms in forest soils ranged between 106 and 108 MPN (g dry soil)-1, which was markedly higher than those in volcanic deposit and water samples, and strongly correlated with the rate of COS degradation in environmental samples. Numerically dominant COS degraders that were isolated from the MPN-positive culture were related to bacteria in the orders Bacillales and Actinomycetales. The present results provide numerical evidence for the ubiquity of COS-degrading microbes in natural environments.

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