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Journal of Nanobiotechnology May 2024Nanoplastics, are emerging pollutants, present a potential hazard to food security and human health. Titanium dioxide nanoparticles (Nano-TiO), serving as...
Titanium dioxide nanoparticles alleviates polystyrene nanoplastics induced growth inhibition by modulating carbon and nitrogen metabolism via melatonin signaling in maize.
BACKGROUND
Nanoplastics, are emerging pollutants, present a potential hazard to food security and human health. Titanium dioxide nanoparticles (Nano-TiO), serving as nano-fertilizer in agriculture, may be important in alleviating polystyrene nanoplastics (PSNPs) toxicity.
RESULTS
Here, we performed transcriptomic, metabolomic and physiological analyzes to identify the role of Nano-TiO in regulating the metabolic processes in PSNPs-stressed maize seedlings (Zea mays L.). The growth inhibition by PSNPs stress was partially relieved by Nano-TiO. Furthermore, when considering the outcomes obtained from RNA-seq, enzyme activity, and metabolite content analyses, it becomes evident that Nano-TiO significantly enhance carbon and nitrogen metabolism levels in plants. In comparison to plants that were not subjected to Nano-TiO, plants exposed to Nano-TiO exhibited enhanced capabilities in maintaining higher rates of photosynthesis, sucrose synthesis, nitrogen assimilation, and protein synthesis under stressful conditions. Meanwhile, Nano-TiO alleviated the oxidative damage by modulating the antioxidant systems. Interestingly, we also found that Nano-TiO significantly enhanced the endogenous melatonin levels in maize seedlings. P-chlorophenylalanine (p-CPA, a melatonin synthesis inhibitor) declined Nano-TiO-induced PSNPs tolerance.
CONCLUSIONS
Taken together, our data show that melatonin is involved in Nano-TiO-induced growth promotion in maize through the regulation of carbon and nitrogen metabolism.
Topics: Zea mays; Titanium; Nitrogen; Carbon; Melatonin; Polystyrenes; Seedlings; Nanoparticles; Signal Transduction; Photosynthesis; Oxidative Stress
PubMed: 38760823
DOI: 10.1186/s12951-024-02537-x -
Scientific Reports May 2024A green technique that emerged as a promise in the degradation of numerous organic contaminants is photocatalysis. The aim of this study concerns photocatalytic...
A green technique that emerged as a promise in the degradation of numerous organic contaminants is photocatalysis. The aim of this study concerns photocatalytic degradation of organic using titanium dioxide nano particles (TiO NPs) which syntheses from ilmenite by different leaching methods using different ingredients such as HCl, HNO and Aqua Regia. The affecting factors such as rate of addition, reaction time, ilmenite grain size, acid to ilmenite ratio and reaction temperature were conducted. Comprehensive physicochemical characterization of Ilmenite and TiO NPs were conducted using different analytical techniques such as XRD, XRF, SEM, TEM and FTIR. Photocatalytic degradation of organics is confirmed by studies of affecting factors on the effectiveness of TiO NPs such as dose, agitation forces, light intensity, initial concentration, pH, time, and temperature. The removal percentages of TSS, COD, BOD and TN of organics were explored. From the results the maximum removal percentage of TSS were 97.3 and 96.9% before and after secondary treatment conducted using ferric chloride (FC). The maximum removal percentage of TKN, BOD, and COD before secondary treatment were conducted using mixture of TiO NPs, FC, and chitosan, which reached 44.2, 44 and 46.3%, respectively. The maximum removal percentage of TKN, BOD, and COD after secondary treatment were conducted using mixture of TiO NPs, FC, and chitosan, which reached 94.9, 99.7 and 99.6%, respectively. Overall, the results derived from this investigation suggest that the TiO NPs/UV holds significant advanced treatment of sewage water, making it a viable choice for water reuse applications.
PubMed: 38760395
DOI: 10.1038/s41598-024-53617-9 -
The Journal of Prosthetic Dentistry May 2024Cantilevered complete arch implant-supported prostheses are commonly fabricated from zirconia and more recently from strength gradient zirconia. Different polymer-based...
STATEMENT OF PROBLEM
Cantilevered complete arch implant-supported prostheses are commonly fabricated from zirconia and more recently from strength gradient zirconia. Different polymer-based materials indicated for definitive fixed prostheses that could be used with additive or subtractive manufacturing have also been marketed recently. However, knowledge on the long-term fatigue behavior of cantilevered implant-supported prostheses made from these polymer-based materials and strength gradient zirconia is lacking.
PURPOSE
The purpose of this in vitro study was to evaluate the fatigue behavior of implant-supported cantilevered prostheses of recently introduced computer-aided design and computer-aided manufacturing polymers and zirconia.
MATERIAL AND METHODS
A master standard tessellation language file of a 9×11×20-mm specimen with a titanium base (Ti-base) space that represented an implant-supported cantilevered prosthesis was used to fabricate specimens from additively manufactured interim resin (AM), polymethyl methacrylate (SM-PM), nanographene-reinforced polymethyl methacrylate (SM-GR), high-impact polymer composite resin (SM-CR), and strength gradient zirconia (SM-ZR) (n=10). Each specimen was prepared by following the respective manufacturer's recommendations, and Ti-base abutments were cemented with an autopolymerizing luting composite resin. After cementation, the specimens were mounted in a mastication simulator and subjected to 1.2 million loading cycles under 100 N at 1.5 Hz; surviving specimens were subjected to another 1.2 million loading cycles under 200 N at 1.5 Hz. The load was applied to the cantilever extension, 12-mm from the clamp of the mastication simulator. The Kaplan-Meier survival analysis and Cox proportional hazards model were used to evaluate the data (α=.05).
RESULTS
Significant differences in survival rate and hazard ratio were observed among materials (P<.001). Among tested materials, SM-ZR had the highest and AM had the lowest survival rate (P≤.031). All materials had a significantly higher hazard ratio than SM-ZR (P≤.011) in the increasing order of SM-GR, SM-PM, SM-CR, and AM.
CONCLUSIONS
SM-ZR had the highest survival rate with no failed specimens. Even though most of the tested polymer-based materials failed during cyclic loading, these failures were commonly observed during the second 1.2 million loading cycles with 200 N. All materials had a higher hazard ratio than SM-ZR.
PubMed: 38760311
DOI: 10.1016/j.prosdent.2024.05.001 -
The British Journal of Oral &... Apr 2024This systematic review aimed to evaluate results reported in the literature regarding the success rate of the titanium mesh technique for the placement of dental... (Review)
Review
This systematic review aimed to evaluate results reported in the literature regarding the success rate of the titanium mesh technique for the placement of dental implants. The topic focused on titanium mesh used as a physical barrier for ridge reconstruction in cases of partial or total edentulism. The authors conducted an electronic search of four databases up to October 2023. Six articles fulfilled the inclusion criteria and were analysed. A total of 100 titanium meshes with a minimum of 4.6 months follow up after surgery were studied, and 241 implants were placed. The review shows that the use of titanium mesh is a predictable method for the rehabilitation of complex atrophic sites. Further investigation generating long-term data is needed to confirm these findings.
PubMed: 38760261
DOI: 10.1016/j.bjoms.2024.04.005 -
RSC Advances May 2024In dye sensitized solar cells, the role of the electron transport layer is crucial because it makes it easier for photo-generated electrons to get from the dye to the...
In dye sensitized solar cells, the role of the electron transport layer is crucial because it makes it easier for photo-generated electrons to get from the dye to the external circuit. In DSSCs, the utilization of TiO is likely to be given preference in the production of electron transport electrodes due to its notable characteristics such as its expansive surface area, porosity, and capacity to scatter light. Nevertheless, the presence of heterogeneity within the mesoporous structure increases the likelihood of TiO aggregation, which subsequently diminishes the beneficial impact of TiO on the performance of DSSCs. In this context, reduced graphene oxide (r-GO) is introduced as an additive into the TiO network during the preparation of TiO/reduced graphene oxide (r-GO) composites. The integration of r-GO with TiO has been recognized as a promising approach to enhance electron transport and electron lifespan, owing to remarkable qualities exhibited by r-GO. The present investigation involved the synthesis of a composite material including titanium dioxide/reduced graphene oxide (TiO/r-GO) through the utilization of the co-precipitation technique. Following this, the generated TiO/r-GO composite material and pure TiO were deposited on FTO through electrophoretic deposition to obtain an electron transport electrode of a dye sensitized solar cell. It should be noted that when r-GO was combined with TiO, the performance of DSSCs improved notably compared to pure TiO. As a result, the findings of this work have significant implications for the advancement of the TiO/r-GO composite deposited through electrophoretic deposition. The power conversion efficiency reached 6.64% with the addition of r-GO in the metal oxide electron transport electrode. The obtained findings align with the outcomes of electrochemical impedance investigations in which the electrode constructed with TiO/r-GO exhibits reduced electron transport resistance () at the anode/dye/electrolyte interface, as well as lower overall resistance () in comparison to TiO-based DSSCs. These advancements have the potential to be employed in commercial DSSC manufacturing.
PubMed: 38756851
DOI: 10.1039/d4ra00829d -
Cureus Apr 2024Pneumoconiosis is a form of interstitial lung disease (ILD) that commonly occurs secondary to occupational or environmental exposures. This is an emerging disease as...
Pneumoconiosis is a form of interstitial lung disease (ILD) that commonly occurs secondary to occupational or environmental exposures. This is an emerging disease as there are many potential forms of pathologic insults. Further adding to the complication is that clinical symptomatology secondary to pneumoconiosis can have long latent periods, as repetitive exposure over years leads to long-standing inflammation and subsequent irreversible damage. Exposure to asbestos, coal, silica, aluminum, talc, hay, and many more agents has the potential to cause pneumoconiosis. This case highlights a veteran, who made his career working with heavy metals such as chromium, beryllium, and titanium in the aerospace defense industry. This case discusses high-risk occupations, a workup for suspected pneumoconiosis, management, and the mechanism of lung injury underlying the three aforementioned pathologic agents. In each case of pneumoconiosis, a thorough history is essential, and diagnoses are made via the incorporation of the patient's historical risk factors, pulmonary function test (PFT) findings, and high-resolution chest computed tomography (HRCT).
PubMed: 38756299
DOI: 10.7759/cureus.58392 -
Bioactive Materials Aug 2024Healing of fractures or bone defects is significantly hindered by overactivated osteoclasts and inhibited osteogenesis in patients with abnormal bone metabolism. Current...
Healing of fractures or bone defects is significantly hindered by overactivated osteoclasts and inhibited osteogenesis in patients with abnormal bone metabolism. Current clinical approaches using titanium alloys or stainless steel provide mechanical support but have no biological effects on bone regeneration. Therefore, designing and fabricating degradable metal materials with sufficient mechanical strength and bidirectional regulation of both osteoblasts and osteoclasts is a substantial challenge. Here, this study first reported an adaptive biodegradable Zn-0.8 Mg alloy with bidirectional regulation of bone homeostasis, which promotes osteogenic differentiation by activating the Pi3k/Akt pathway and inhibits osteoclast differentiation by inhibiting the GRB2/ERK pathway. The -osteolytic ability of the Zn-0.8 Mg alloy was verified in a mouse calvarial osteolysis model and its suitability for internal fracture fixation with high-strength screws was confirmed in the rabbit femoral condyle fracture model. Furthermore, in an aged postmenopausal rat femoral condyle defect model, 3D printed Zn-0.8 Mg scaffolds promoted excellent bone regeneration through adaptive structures with good mechanical properties and bidirectionally regulated bone metabolism, enabling personalized bone defect repair. These findings demonstrate the substantial potential of the Zn-0.8 Mg alloy for treating fractures or bone defects in patients with aberrant bone metabolism.
PubMed: 38756201
DOI: 10.1016/j.bioactmat.2024.04.027 -
Journal of Orthopaedic Surgery and... May 2024This study aims to evaluate the optimal ratio of synthetic bone graft (SBG) material and platelet rich fibrin (PRF) mixed in a metal 3D-printed implant to enhance bone...
BACKGROUND
This study aims to evaluate the optimal ratio of synthetic bone graft (SBG) material and platelet rich fibrin (PRF) mixed in a metal 3D-printed implant to enhance bone regeneration.
METHODS
Specialized titanium hollow implants (5 mm in diameter and 6 mm in height for rabbit; 6 mm in diameter and 5 mm in height for pig) were designed and manufactured using 3D printing technology. The implants were divided into three groups and filled with different bone graft combinations, namely (1) SBG alone; (2) PRF to SBG in 1:1 ratio; (3) PRF to SBG in 2:1 ratio. These three groups were replicated tightly into each bone defect in distal femurs of rabbits (nine implants, n = 3) and femoral shafts of pigs (fifteen implants, n = 5). Animal tissue sections were obtained after euthanasia at the 8th postoperative week. The rabbit specimens were stained with analine blue, while the pig specimens were stained with Masson-Goldner's trichrome stain to perform histologically examination. All titanium hollow implants were well anchored, except in fracture specimens (three in the rabbit and one fracture in the pig).
RESULT
Rabbit specimens under analine blue staining showed that collagen tissue increased by about 20% and 40% in the 1:1 ratio group and the 2:1 ratio group, respectively. Masson-Goldner's trichrome stain results showed that new bone growth increased by 32% in the 1:1 ratio PRF to SBG, while - 8% in the 2:1 ratio group.
CONCLUSION
This study demonstrated that placing a 1:1 ratio combination of PRF and SBG in a stabilized titanium 3D printed implant resulted in an optimal increase in bone growth.
Topics: Animals; Printing, Three-Dimensional; Rabbits; Platelet-Rich Fibrin; Bone Regeneration; Swine; Titanium; Femur; Bone Substitutes; Bone Transplantation; Prostheses and Implants
PubMed: 38755635
DOI: 10.1186/s13018-024-04784-y -
Global Spine Journal May 2024Retrospective cohort study.
Trabecular Bone Remodeling after Posterior Lumbar Interbody Fusion: Comparison of the Osseointegration in Three-Dimensional Porous Titanium Cages and Polyether-Ether-Ketone Cages.
STUDY DESIGN
Retrospective cohort study.
OBJECTIVES
Imaging changes in the vertebral body after posterior lumbar interbody fusion (PLIF) are determined to be trabecular bone remodeling (TBR). This study aimed to investigate the influence of cage materials on TBR and segment stabilization in PLIF by studying image changes.
METHODS
This was a retrospective study reviewing 101 cases who underwent one-level PLIF with three-dimensional porous titanium (3DTi) cages (53 patients) or polyether-ether-ketone (PEEK) cages (48 patients). Computed tomography images obtained 3 months, 1 year, and 2 years postoperatively were examined for TBR, vertebral endplate cyst formation as an instability sign, cage subsidence, and clear zone around pedicle screw (CZPS).
RESULTS
No significant differences in the TBR-positivity rates were observed between the two cages at 3 months, 1 year, and 2 years postoperatively. However, all 3DTi cage segments that were TBR-positive at 3 months postoperatively showed no CZPS and fewer final instability segments than the TBR-negative segments (0% vs 9%). In contrast, although the PEEK cage segments that were TBR-positive at 3 months postoperatively were not associated with future segmental stabilization, those that were TBR-positive at 1 year postoperatively had fewer final instability segments than the TBR-negative segments (0% vs 33%).
CONCLUSIONS
The 3DTi cage segments with TBR 3 months postoperatively showed significant final segmental stabilization, whereas TBR at 1 year rather than 3 months postoperatively was useful in determining final segmental stabilization for the PEEK cage segments. The timing of TBR, a new osseointegration assessment, were associated with the cage material.
PubMed: 38752287
DOI: 10.1177/21925682241255686 -
Zhongguo Xiu Fu Chong Jian Wai Ke Za... May 2024To evaluate the effectiveness of using titanium alloy trabecular bone three-dimensional (3D) printed artificial vertebral body in treating cervical ossification of the...
OBJECTIVE
To evaluate the effectiveness of using titanium alloy trabecular bone three-dimensional (3D) printed artificial vertebral body in treating cervical ossification of the posterior longitudinal ligament (OPLL).
METHODS
A retrospective analysis was conducted on clinical data from 45 patients with cervical OPLL admitted between September 2019 and August 2021 and meeting the selection criteria. All patients underwent anterior cervical corpectomy and decompression, interbody bone graft fusion, and titanium plate internal fixation. During operation, 21 patients in the study group received titanium alloy trabecular bone 3D printed artificial vertebral bodies, while 24 patients in the control group received titanium cages. There was no significant difference in baseline data such as gender, age, disease duration, affected segments, or preoperative pain visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), vertebral height, and C Cobb angle ( >0.05). Operation time, intraoperative blood loss, and occurrence of complications were recorded for both groups. Preoperatively and at 3 and 12 months postoperatively, the functionality and symptom relief were assessed using JOA scores, VAS scores, and NDI evaluations. The vertebral height and C Cobb angle were detected by imaging examinations and the implant subsidence and intervertebral fusion were observed.
RESULTS
The operation time and incidence of complications were significantly lower in the study group than in the control group ( <0.05), while the difference in intraoperative blood loss between the two groups was not significant ( >0.05). All patients were followed up 12-18 months, with the follow-up time of (14.28±4.34) months in the study group and (15.23±3.54) months in the control group, showing no significant difference ( =0.809, =0.423). The JOA score, VAS score, and NDI of the two groups improved after operation, and further improved at 12 months compared to 3 months, with significant differences ( <0.05). At each time point, the study group exhibited significantly higher JOA scores and improvement rate compared to the control group ( <0.05); but there was no significantly difference in VAS score and NDI between the two groups ( >0.05). Imaging re-examination showed that the vertebral height and C Cobb angle of the two groups significantly increased at 3 and 12 months after operation ( <0.05), and there was no significant difference between 3 and 12 months after operation ( >0.05). At each time point, the vertebral height and C Cobb angle of the study group were significantly higher than those of the control group ( <0.05), and the implant subsidence rate was significantly lower than that of the control group ( <0.05). However, there was no significant difference in intervertebral fusion rate between the two groups ( >0.05).
CONCLUSION
Compared to traditional titanium cages, the use of titanium alloy trabecular bone 3D-printed artificial vertebral bodies for treating cervical OPLL results in shorter operative time, fewer postoperative complications, and lower implant subsidence rates, making it superior in vertebral reconstruction.
Topics: Humans; Titanium; Ossification of Posterior Longitudinal Ligament; Printing, Three-Dimensional; Cervical Vertebrae; Retrospective Studies; Spinal Fusion; Alloys; Decompression, Surgical; Cancellous Bone; Treatment Outcome; Vertebral Body; Female; Male; Bone Plates; Middle Aged
PubMed: 38752238
DOI: 10.7507/1002-1892.202403003