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1.
Can J Neurol Sci ; : 1-6, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39252175

RESUMO

BACKGROUND: To evaluate clinical outcomes and volumetric changes following endoscopic endonasal approach (EEA) for tuberculum sellae (TS) and planum sphenoidale (PS) meningiomas. Key objectives included evaluating pre- and postoperative tumor volumes, visual assessments and EEA-related complications. METHODS: A single-center retrospective study was conducted at Foothills Medical Centre, University of Calgary, Canada, from 2009 to 2022 including 24 patients meeting inclusion criteria for midline skull base tumors, confirmed as WHO Grade I or II meningiomas with optic canal extension. RESULTS: EEA achieved gross total resection in 87.5% of cases, with a mean tumor volume reduction of 92.24%. Postoperatively, 91.67% exhibited visual improvement or stability. Cerebrospinal fluid leaks occurred in 12.5% of cases, necessitating revision surgery in one case. Persistent postoperative endocrine dysfunction affected 4.17%. Preoperative tumor volume did not demonstrate a correlation with complications. CONCLUSIONS: This study delivers reproducible data for pre- and postoperative tumor volume following the EEA after TS or PS meningiomas. The EEA demonstrated favorable radiographic and clinical outcomes in TS and PS meningiomas, achieving gross total resection with minimal morbidity.

2.
Heliyon ; 10(16): e36064, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39229518

RESUMO

High entropy alloys (HEAs) are alloys composed of five or more primary elements in equal or nearly equal proportions of atoms. In the present study, the thermophysical properties of the CoCrFeNiCu high entropy alloy (HEA) were investigated by a molecular dynamics (MD) method at nanoscale. The effects of the content of individual elements on lattice thermal conductivity k p were revealed, and the results suggested that adjusting the atomic content can be a way to control the lattice thermal conductivity of HEAs. The effects of temperature on k p were investigated quantitively, and a power-law relationship of k p with T -0.419 was suggested, which agrees with previous findings. The effects of temperature and the content of individual elements on volumetric specific heat capacity C v were also studied: as the temperature increases, the C v of all HEAs slightly decreases and then increases. The effects of atomic content on C v varied with the comprising elements. To further understand heat transfer mechanisms in the HEAs, the phonon density of states (PDOS) at different temperatures and varying atomic composition was calculated: Co and Ni elements facilitate the high-frequency vibration of phonons and the Cu environment weakens the heat transfer via low-frequency vibration of photons. As the temperature increases, the phonon mean free path (MFP) in the equiatomic CoCrFeNiCu HEA decreases, which may be attributed to the accelerated momentum of atoms and intensified collisions of phonons. The present research provides theoretical foundations for alloy design and have implications for high-performance alloy smelting.

3.
J Environ Manage ; 370: 122416, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39255575

RESUMO

Alternaria is a ubiquitous fungal genus with many allergenic and pathogenic species inhabiting grasslands. We hypothesise that grasslands (natural/man-made) host a diversity of fungal species whose spores have varying emission patterns. Therefore, the purpose of this study was to examine the potential of grasslands for emission, diversity and composition of Alternaria and other fungal species. To test the hypothesis, Hirst-type and multi-vial Cyclone samplers collected air samples from two grassland sites (unmanaged and managed) and a non-grassland site at Lakeside campus of the University of Worcester, United Kingdom for the period May to September 2019. The unmanaged grassland was originally planted with grasses and left uncut for three years. The managed grassland was a roadside verge that was cut once every year, typically after most grasses have flowered. We used optical microscopy and Illumina MiSeq sequencing to investigate the emission, abundance, diversity and composition of the fungal spores from each site alongside meteorological variables. Kruskal-Wallis and Wilcoxon tests examined differences in the bi-hourly Alternaria concentrations between the sites. Shannon's and Simpson's Index determined the diversity of the fungal spores between the unmanaged and non-grassland sites. The results showed that grasslands are a strong source of Alternaria spores with considerably higher numbers of clinically important days compared with the non-grassland site. The managed grassland varied in Alternaria spore emission pattern from the unmanaged, probably due to differences in environmental variables and cutting frequency. The unmanaged grassland and non-grassland sites showed a high diversity of fungi including Alternaria, Cladosporium, Ascochyta, Botrytis and Aureobasidium. Overall, the study shows that grasslands are a strong source of fungal spores with allergenic and pathogenic potential and have varying emission patterns, compared with nearby urban areas where monitoring stations are located. This information is useful for atmospheric modelling of airborne fungal spore sources and has implications for allergy sufferers in particular.

5.
Ann Anat ; : 152329, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39244109

RESUMO

BACKGROUND: The aim of this study was to evaluate clinical one-dimensional changes such as root surface coverage, decrease seen in the amount of gingival recession and keratinised gingival width (KGW) obtained throughout a 6-month follow-up period following the treatment of Cairo class II gingival recession with free gingival graft (FGG) and gingival unit graft (GUG). Three-dimensional changes in gingival volume and thickness were also compared digitally using an indirect method. METHODS: A total of 20 patients with localised Cairo class II gingival recession were randomly separated into two groups; 10 patients were treated with FGG and 10 patients treated with GUG. Preoperatively and at 6 months postoperatively, the initial position of the gingiva and KGW were recorded for all the patients and plaster models were formed from the obtained impressions with the traditional method. The plaster models were transferred to a digital environment by scanning with a model scanner. Using a software program, changes in gingival papillary height and gingival volume and thickness were compared between the groups and according to the baseline values from The Standard Tessellation Language (STL) files obtained. RESULTS: Compared to the baseline values, a significant increase was determined in the KGW, and a significant decrease in pocket depth, clinical attachment level, and gingiva recession depth in all the groups (p<0.05). No statistically significant difference was determined between the groups in respect of the changes in mean gingiva thickness, gingiva volume, and mean vertical papillary height (p>0.05). CONCLUSION: The study results showed that GUG treatment for Cairo class II localised gingival recession is an effective method in respect of increasing gingiva volume and thickness, increasing KGW, coverage of the root surface, and forming tissue contours that allow the patient to easily maintain oral hygiene. However, there was not seen to be any adventage of GUG and FGG over each other.

6.
Radiol Phys Technol ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39249637

RESUMO

This study investigated the effectiveness of placing skin-ring structures to enhance the precision of skin dose calculations in patients who had undergone head and neck volumetric modulated arc therapy using the Acuros XB algorithm. The skin-ring structures in question were positioned 2 mm below the skin surface (skin A) and 1 mm above and below the skin surface (skin B) within the treatment-planning system. These structures were then tested on both acrylic cylindrical and anthropomorphic phantoms and compared with the Gafchromic EBT3 film (EBT3). The results revealed that the maximum dose differences between skins A and B for the cylindrical and anthropomorphic phantoms were approximately 12% and 2%, respectively. In patients 1 and 2, the dose differences between skins A and B were 9.2% and 8.2%, respectively. Ultimately, demonstrated that the skin-dose calculation accuracy of skin B was within 2% and did not impact the deep organs.

7.
Matter ; 7(6): 2184-2204, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-39221109

RESUMO

Tissue engineering has long sought to rapidly generate perfusable vascularized tissues with vessel sizes spanning those seen in humans. Current techniques such as biological 3D printing (top-down) and cellular self-assembly (bottom-up) are resource intensive and have not overcome the inherent tradeoff between vessel resolution and assembly time, limiting their utility and scalability for engineering tissues. We present a flexible and scalable technique termed SPAN - Sacrificial Percolation of Anisotropic Networks, where a network of perfusable channels is created throughout a tissue in minutes, irrespective of its size. Conduits with length scales spanning arterioles to capillaries are generated using pipettable alginate fibers that interconnect above a percolation density threshold and are then degraded within constructs of arbitrary size and shape. SPAN is readily used within common tissue engineering processes, can be used to generate endothelial cell-lined vasculature in a multi-cell type construct, and paves the way for rapid assembly of perfusable tissues.

8.
Nanophotonics ; 13(20): 3805-3814, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39224784

RESUMO

Volumetric subcellular imaging has long been essential for studying structures and dynamics in cells and tissues. However, due to limited imaging speed and depth of field, it has been challenging to perform live-cell imaging and single-particle tracking. Here we report a 2.5D fluorescence microscopy combined with highly inclined illumination beams, which significantly reduce not only the image acquisition time but also the out-of-focus background by ∼2-fold compared to epi-illumination. Instead of sequential z-scanning, our method projects a certain depth of volumetric information onto a 2D plane in a single shot using multi-layered glass for incoherent wavefront splitting, enabling high photon detection efficiency. We apply our method to multi-color immunofluorescence imaging and volumetric super-resolution imaging, covering ∼3-4 µm thickness of samples without z-scanning. Additionally, we demonstrate that our approach can substantially extend the observation time of single-particle tracking in living cells.

9.
J Appl Clin Med Phys ; : e14488, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39226472

RESUMO

PURPOSE: The aim of this study is to determine the effect of forcing and filling the electron density (ED) to 1.0 of the planning target volume (PTV) overdose distribution in lung SBRT treatment leading to shortening patient treatment time and increasing patient comfort by reducing MU/fraction due to ED manipulation effect. METHODS: In this study, 36 lung SBRT plans of 12 suitable patients who prescribed a total dose of 50 Gy in five fractions were generated with Monaco v.5.10 TPS using the Monte Carlo (MC) algorithm and volumetric modulated arc therapy (VMAT) technique by PTV ED values forcing as well as filling to 1.0 and comparatively assessed. The first group of plans was created by using the patient's original ED, second and third groups of plans were reoptimized by forcing and filling the ED of PTV to 1.0, respectively, therefore acquiring a new dose distribution which lead to comparatively assessment the effects of changes in ED on PTV and OAR doses. RESULTS: Assessment of treatment plans revealed that mean MU/fx numbers were decreased by 76% and 75.25% between Groups 1 and 2, Groups 1 and 3, respectively. The number of segments was also reduced in Group 1 by up to 15% compared with Groups 2 and 3. Maximum HI and CI differences for PTV between Groups 1 and 2 were less than 1% and Groups 1 and 3 were 1.5% which indicates all 3 group plans were comparable in terms of dose distribution within PTV. CONCLUSIONS: Forcing and filling the ED of PTV to 1.0 strategy has provided reduced a number of segments and MU/fx without a significant change in PTV mean and maximum doses, thereby decreasing treatment time and patient discomfort during treatment. This process should be considered in line of a potential number of patients as well as prescribed dose and MU/fx numbers.

10.
J Xray Sci Technol ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39093110

RESUMO

INTRODUCTION: Intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) are the main radiotherapy techniques for treating and managing rectal cancer. Collimator rotation is one of the crucial parameters in radiotherapy planning, and its alteration can cause dosimetric variations. This study assessed the effect of collimator rotation on the dosimetric results of various IMRT and VMAT plans for rectal cancer. MATERIALS AND METHODS: Computed tomography (CT) images of 20 male patients with rectal cancer were utilized for IMRT and VMAT treatment planning with various collimator angles. Nine different IMRT techniques (5, 7, and 9 coplanar fields with collimator angles of 0°, 45°, and 90°) and six different VMAT techniques (1 and 2 full coplanar arcs with collimator angles of 0°, 45°, and 90°) were planned for each patient. The dosimetric results of various treatment techniques for target tissue (conformity index [CI] and homogeneity index [HI]) and organs at risk (OARs) sparing (parameters obtained from OARs dose-volume histograms [DVH]) as well as radiobiological findings were analyzed and compared. RESULTS: The 7-fields IMRT technique demonstrated lower bladder doses (V40Gy, V45Gy), unaffected by collimator rotation. The 9-fields IMRT and 2-arcs VMAT (excluding the 90-degree collimator) had the lowest V35Gy and V45Gy. A 90-degree collimator rotation in 2-arcs VMAT significantly increased small bowel and bladder V45Gy, femoral head doses, and HI values. Radiobiologically, the 90-degree rotation had adverse effects on small bowel NTCP (normal tissue complication probability). No superiority was found for a 45-degree collimator rotation over 0 or 30 degrees in VMAT techniques. CONCLUSION: Collimator rotation had minimal impact on dosimetric parameters in IMRT planning but is significant in VMAT techniques. A 90-degree rotation in VMAT, particularly in a 2-full arc technique, adversely affects PTV homogeneity index, bladder dose, and small bowel NTCP. Other evaluated collimator angles did not significantly affect VMAT dosimetrical or radiobiological outcomes.

11.
Artigo em Inglês | MEDLINE | ID: mdl-39105842

RESUMO

INTRODUCTION: Effective tools to evaluate bone quality preoperatively are scarce and the standard method to determine bone quality requires an invasive biopsy. A non-invasive, and preoperatively available method for bone quality assessment would be of clinical value. The purpose of this study is to investigate the associations of bone formation marker, serum bone alkaline phosphatase (BAP), and bone resorption marker, urine collagen cross-linked N-telopeptide (uNTX) to volumetric bone mineral density (vBMD), fluorescent advanced glycation endproducts (fAGEs) and bone microstructure. MATERIALS AND METHODS: A cross-secional analysis using prospective data of patients undergoing lumbar spinal fusion was performed. BAP and uNTX were preoperatively collected. Quantitative computed tomography (QCT) was performed at the lumbar spine (vBMD ≤ 120 mg/cm3 osteopenic/osteoporotic). Bone biopsies from the posterior superior iliac spine were obtained and evaluated with multiphoton fluorescence microscopy for fAGEs and microcomputed tomography (µCT) for bone microarchitecture. Correlations between BAP/uNTX to vBMD, fAGEs and µCT parameters were assessed with Spearman's ρ. Receiver operating characteristic (ROC) analysis evaluated BAP and uNTX as predictors for osteopenia/osteoporosis. Multivariable linear regression models adjusting for age, sex, BMI, race and diabetes mellitus determined associations between BAP/uNTX and fAGEs. RESULTS: 127 prospectively enrolled patients (50.4% female, 62.5 years, BMI 28.7 kg/m2) were analyzed. uNTX (ρ=-0.331,p < 0.005) and BAP (ρ=-0.245,p < 0.025) decreased with cortical fAGEs, and uNTX (ρ=-0.380,p < 0.001) decreased with trabecular fAGEs. BAP and uNTX revealed no significant correlation with vBMD. ROC analysis for BAP and uNTX discriminated osteopenia/osteoporosis with AUC of 0.477 and 0.561, respectively. In the multivariable analysis, uNTX decreased with increasing trabecular fAGEs after adjusting for covariates (ß = 0.923;p = 0.031). CONCLUSION: This study demonstrated an inverse association of bone turnover markers and fAGEs. Both uNTX and BAP could not predict osteopenia/osteoporosis in the spine. uNTX reflects collagen characteristics and might have a complementary role to vBMD, as a non-invasive tool for bone quality assessment in spine surgery.

12.
Cureus ; 16(7): e64068, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39114217

RESUMO

This review article examines the effectiveness of incorporating autologous endometrial cells and platelet-rich plasma (PRP) through hysteroscopic injections within the field of assisted reproductive technology (ART). This study assesses the outcomes of these injections on the susceptibility of the endometrium, the dynamics of the uterus, and the frequencies of pregnancy in individuals with refractory thin endometrium. Based on a complete examination of several trials, it becomes apparent that autologous PRP injections provide encouraging turnouts in augmenting endometrial thickness, raising endometrial receptivity, and, in the end, raising chances of being pregnant and successful delivery. The research highlights the promise of autologous PRP and minimally changed endometrial cellular treatments in enhancing outcomes in ART, especially for people who have had problems with implantation. This article gives a whole evaluation of the medical use of and upgrades regarding the utilization of infusions of PRP and autologous endometrial cells under hysteroscopic control to deal with infertility issues related to endometrial health through the synthesis of contemporary studies.

13.
Nanotechnology ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39111321

RESUMO

In the contemporary landscape of technological advancements, the burgeoning demand for portable electronics and flexible wearable devices has necessitated the development of energy storage systems with superior volumetric performance. Tungsten oxide (WO3), known for its high density and theoretical capacitance, is a promising electrode material for supercapacitors. However, low conductivity and poor cycling stability are still the key bottlenecks for its application. Herein, a novel composite comprising hollow porous WO3 spheres (HPWS) derived by template method was electrostatic self-assembled on the surface of the Ti3C2Tx nanosheets. The resulting electrodes exhibited ultra-high volumetric capacitance of 1930 F cm-3 at 1 A g-1 and rate capability of 46% at 50 A g-1, attributed to enhanced ion accessibility from microporous structure and electron transport from conductive network of Ti3C2Tx even at a high packing density of 3.86 g cm-3. Utilizing HPWS/Ti3C2Tx as the negative electrode and porous carbon as the positive electrode, the assembled asymmetric supercapacitor achieved an energy density of 31 Wh kg-1 at a power density of 650 W kg-1 with over 107% capacitance retention after 5000 cycles. This work provides a promising approach for developing next-generation supercapacitors with ultra-high volumetric capacitance.

14.
Artigo em Inglês | MEDLINE | ID: mdl-39112341

RESUMO

AIMS: Tumour response assessments, as per Response Evaluation Criteria in Solid Tumours (RECIST 1.1), are based on the sum of diameters (SODs) of the primary tumour (longest diameter) and/or short axis diameter of lymph nodes. This study evaluates the response categorisation as per RECIST 1.1 vs Computed tomography (CT) based volumetric assessment of RECIST (proposed as vRECIST) in locally advanced head and neck cancers (LAHNCs) undergoing treatment. MATERIAL AND METHODS: The pre-treatment SODs and CT estimated tumour volumes were recorded in 45 LAHNCs treated with radiotherapy (RT), chemoradiotherapy (CTRT) or thermochemoradiotherapy (HTCTRT). Tumour responses were assessed independently as per RECIST 1.1 and vRECIST by two radiation oncologists and grouped into complete response (CR), partial response (PR), stable disease (SD) or progressive disease (PD). These response groups were evaluated for the likely congruence of the two approaches, as categorised independently by these two observers. RESULTS: All patients in stages III (n = 7), IVA (n = 16) and IVB (n = 22) were inoperable and had received either RT alone (n = 1), CTRT (n = 12) or HTCTRT (n = 32). Based on SODs criteria of RECIST 1.1, of the 45 patients, 5 and 40 were grouped as PR and SD by the first observer, while this changed to 34 and 10, respectively and 1 PD, with vRECIST (p < 0.001). Similarly, for the second observer, the 4 PR and 41 SD grouped using RECIST 1.1 were recategorised to 34 PR, 10 SD, and 1 PD by vRECIST (p < 0.001). Thus, a mismatch of 66.6% and 68.8%, respectively, was evident by observers first and second in categorising SD based on SODs of RECIST 1.1 vs PR on vRECIST. CONCLUSIONS: Treatment responses in LAHNCs assessed using SODs resulted in significant uncertainties and failed to reflect actual volumetric changes in tumours during treatment. It is perhaps time to consider replacing the SODs of RECIST 1.1 with vRECIST for unequivocal tumour response categorisation in the present era of image-based oncology practice.

15.
Cureus ; 16(7): e64532, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39156407

RESUMO

Dural arteriovenous fistulas (dAVFs) are anomalous connections between arteries and veins within the dura mater, involving dural sinuses, bridging veins, or emissary veins. If untreated, these lesions can result in intracranial hemorrhage. The management of posterior fossa dAVFs is challenging due to the intricate venous anatomy near the brainstem and cranial nerves. This study leverages three-dimensional (3D) technology combined with dissections to understand the anatomy and microsurgical techniques for treating infratentorial dAVFs. Five embalmed heads and one dry skull were used to meticulously document the pertinent anatomy of the infratentorial compartment. Advanced 3D technology, including 3D sculpting and structured light scanning, was employed to construct high-resolution volumetric models (VMs). Two-dimensional (2D) images of dissections and VMs illustrate key anatomical landmarks of the posterior fossa. Infratentorial dAVFs primarily involve sinuses, which are divided into groups based on their location: basal, medullary, and petrosal. Most of the arterial supply originates from the external carotid artery, especially the ascending pharyngeal artery. This is followed by meningeal branches from the internal carotid artery (ICA) and vertebrobasilar system. The surgical approaches to treat infratentorial dAVFs include the retrosigmoid and far lateral approaches and their modifications. Our study describes the relevant vascular anatomy of the infratentorial compartment, focusing on the surgical treatment of infratentorial dAVFs. In conjunction with the included interactive models, this study improves our educational capabilities regarding the intricate vascular neuroanatomical features of this region. When applied to a clinical setting, precise anatomical knowledge and VMs tools enhance surgical outcomes, reduce complications, and ultimately improve patient care.

16.
Technol Cancer Res Treat ; 23: 15330338241264848, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39129335

RESUMO

OBJECTIVE: To investigate the effect of various frequencies of bolus use on the superficial dose of volumetric modulated arc therapy after modified radical mastectomy for breast cancer. METHODS: Based on the computed tomography images of a female anthropomorphic breast phantom, a 0.5 cm silicone-based 3D-printed bolus was created. Nine points evenly distributed on the breast skin were selected for assessing the skin dose, and a volume of subcutaneous lymphatic drainage of the breast (noted as ROI2-3) was delineated for assessing the chest wall dose. The treatment plans with and without bolus (plan_wb and plan_nb) were separately designed using the prescription of 50 Gy in 25 fractions following the standard dose constraints of the adjacent organ at risk. To characterize the accuracy of treatment planning system (TPS) dose calculations, the doses of the nine points were measured five times by thermoluminescence dosimeters (TLDs) and then were compared with the TPS calculated dose. RESULTS: Compared with Plan_nb (144.46 ± 10.32 cGy), the breast skin dose for plan_wb (208.75 ± 4.55 cGy) was significantly increased (t = -18.56, P < 0.001). The deviation of skin dose was smaller for Plan_wb, and the uniformity was significantly improved. The calculated value of TPS was in good agreement with the measured value of TLD, and the maximum deviation was within 5%. Skin and ROI2-3 doses were significantly increased with increasing frequencies of bolus applications. The mean dose of the breast skin and ROI2-3 for 15 and 23 times bolus applications were 45.33 Gy, 50.88 Gy and 50.36 Gy, 52.39 Gy, respectively. CONCLUSION: 3D printing bolus can improve the radiation dose and the accuracy of the planned dose. Setting Plan_wb to 15 times for T1-3N+ breast cancer patients and 23 times for T4N+ breast cancer patients can meet the clinical need. Quantitative analysis of the bolus application frequency for different tumor stages can provide a reference for clinical practice.


Assuntos
Neoplasias da Mama , Mastectomia Radical Modificada , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Feminino , Radioterapia de Intensidade Modulada/métodos , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Planejamento da Radioterapia Assistida por Computador/métodos , Mastectomia Radical Modificada/métodos , Radiometria/métodos , Órgãos em Risco , Tomografia Computadorizada por Raios X
17.
Br J Clin Pharmacol ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152547

RESUMO

AIM: Chemotherapy-induced peripheral neuropathy (CIPN) is a major toxicity limiting the use of nab-paclitaxel (Nab-P) in treating patients with pancreatic cancer. The aim of this study was to identify the factors affecting CIPN using patient-reported outcome measures and the minimally invasive volumetric absorptive microsampling (VAMS) technique. METHODS: The maximum concentrations of paclitaxel (Cmax) were measured from 81 VAMS samples collected from 44 participants with pancreatic cancer. The association between CIPN development and demographic, clinical and pharmacokinetic factors was determined using univariable and multivariable logistic regression. The association between CIPN severity and the factors was evaluated using Spearman's rank correlation. The impact of Cmax and the number of treatment cycles on the severity was assessed using multivariable linear regression. RESULTS: The development of CIPN was significantly associated with cumulative dose (odds ratio 1.005, 95% confidence interval [CI] 1.003-1.007), treatment cycles (3.47, 2.25-5.85), alkaline phosphate (0.992, 0.985-0.998) and age (1.092, 1.020-1.179), with an area under the receiver operating characteristic curve of 0.89 (95% CI 0.83-0.95). The severity of CIPN significantly worsened with increasing cumulative dose (coefficient 0.58, 95% CI 0.44-0.69), treatment cycles (0.57, 0.44-0.68) and age (0.18, 0.00-0.35). The severity of CIPN was predictable from treatment cycles (P = .0002) and Cmax (P = .01). CONCLUSION: The higher the cumulative dose of Nab-P, treatment cycles and age, the more frequently and severely do the patients experience CIPN. In predicting the severity of CIPN using Cmax, minimally invasive VAMS is a feasible alternative to venous blood sampling.

18.
Instrum Sci Technol ; 52(4): 433-455, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39100769

RESUMO

The concept of a 2D cylindrical High Pass Ladder (2D c-HPL) is used in the development of this ultra high radio frequency (UHRF) volumetric head coil for 7T tuned at the Larmor frequency of 298 MHz. The architecture of the 2D c-HPL helps to overcome the challenges associated with non-uniform magnetic field distribution. The prototype consists of an individual resonating array of inductance-capacitance (LC) elements and each component is tuned to the precise f o frequency. The tuning of the (i) inductance, (ii) capacitance, (iii) mesh size, and (iv) coupling coefficient play critical roles to attain the desired Larmor frequency. For this proof-of-concept, the prototype of a volumetric head coil consists of a cylindrical array size of 4 ×6, with individual LC components of inductance magnitude, 98 nH and four fixed value capacitors and one tunable capacitor that allowed to achieve the desired precession frequency, f r = 298 M H z . The model was tested for three different f o values of 269 MHz, 275 MHz and 286 MHz. The mutual coupling and the eigenfrequencies were compared through bench testing and dispersion equation. The experimental data were in good agreement (< 5%) with the theoretical eigenfrequencies from the dispersion relation. The theoretical eigenfrequencies and the experimental eigenfrequencies are in good agreement for eigenmodes (1,2), (1,3), (2,2), (2,3) and (4,3).

19.
Dent Mater ; 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39098487

RESUMO

Polymerization shrinkage of bonded resin composite restorations will result in the development of curing contraction stresses during setting and can cause debonding of the restoration or failure of the surrounding tooth structure. However, the hygroscopic expansion that occurs after exposure of the restorative to the wet oral environment can compensate for this shrinkage. OBJECTIVES: The purpose of this study was to determine the hygroscopic expansion of six commercial resin composites and relate it to their composition, mechanical properties, shrinkage, and contraction stress development. METHODS: Short-term volumetric shrinkage and contraction stress of the different composites were measured by mercury dilatometry and a universal testing machine. The long-term contraction stress was measured by the deflection of a bilayer strip of metal and a resin composite, which were stored dry as well as wet to determine the effect of hygroscopic expansion. The curvature of the strip was measured by profilometry over a period of 3 months. RESULTS: The curvature of the strip correlated well (r2 =0.74) with the initial contraction stress, showing that the contraction stress is an important factor in initial deformation. The water sorption in all specimens showed that the initial deformation, within 2-4 weeks after curing, was completely counteracted. A high correlation (r2 =0.90) between deflection and relative water sorption was found, where the relative water sorption is defined as the absolute water sorption corrected for the inorganic filler volume of the composite. SIGNIFICANCE: Within a period of 2-4 weeks after curing most of the curing contraction stresses of resin composite restoratives will be released by hygroscopic expansion.

20.
Vet Anaesth Analg ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39138051

RESUMO

OBJECTIVE: To compare the portion of tidal volume (VT) ventilating dead space volumes in nonbrachycephalic cats and dogs with small body mass receiving volume-controlled ventilation (VCV) with a fixed VT. STUDY DESIGN: Prospective, experimental study. ANIMALS: A group of eight healthy adult cats and dogs [ideal body weight (IBW): 3.0 ± 0.5 and 3.8 ± 1.1 kg, respectively]. METHODS: Anesthetized cats and dogs received VCV with a 12 mL kg-1 VT (inspiratory pause ≥ 0.5 seconds). Respiratory rate (fR) was adjusted to maintain normocapnia. Airway dead space (VDaw) and alveolar tidal volume (VTalv) were measured by volumetric capnography. Physiological dead space (VDphys) and VDphys/VT ratio were calculated using the Bohr-Enghoff method. Data recorded before surgery were compared by an unpaired t-test or Mann-Whitney U test (p < 0.05 considered significant). RESULTS: The IBW (p = 0.07), PaCO2 (p = 0.40) and expired VT [VT(exp)] (p = 0.77) did not differ significantly between species. The VDaw (mL kg-1) was lower in cats (3.7 ± 0.4) than in dogs (7.7 ± 0.9) (p < 0.0001). The VTalv (mL kg-1) was larger in cats (8.3 ± 0.7) than in dogs (4.3 ± 0.7) (p < 0.0001). Cats presented a smaller VDphys/VT ratio (0.33 ± 0.03) and VDphys (4.0 ± 0.3 mL kg-1) than dogs (VDphys/VT: 0.60 ± 0.09; VDphys: 7.2 ± 1.4 mL kg-1) (p < 0.0001). The fR and minute ventilation (VT(exp) × fR) were lower in cats than in dogs (p = 0.048 and p = 0.038, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: A fixed VT results in more effective ventilation in cats than in dogs with small body mass because of species-specific differences in and VDaw and VDphys. Because of the smaller VDaw and VDphys in cats than in dogs, a lower fR is required to maintain normocapnia in cats.

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