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1.
Cureus ; 16(2): e54975, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38544626

RESUMO

A direct sliding inguinal hernia descends through the superficial inguinal ring and encroaches on nearby organ structures, such as the bladder. This type of hernia is rare with a 2-5% incidence and occurs due to a weakness within the lower abdominal wall, usually associated with advancing age, that permits the distal colon to descend into the inguinal canal. Direct sliding inguinal hernias are a rare subset of inguinal hernias that require meticulous dissection due to their incorporation of nearby organs such as the bladder or colon. Few cases report repair of these hernias laparoscopically; however, the use of a hybrid laparoscopic/open approach has not been extensively documented and it may be beneficial to explore the use of this approach in inguinal hernia repair.  We present a case of a robotic-assisted minimally invasive repair of a direct sliding inguinal hernia in an 85-year-old male. He initially presented to the emergency department with left-sided groin pain and imaging revealed he had a direct sliding inguinal hernia that incorporated the bladder wall. He was admitted to surgery for a robotic-assisted minimally invasive inguinal hernia repair with mesh. During the surgery, after seeing the extent at which the hernia sac incorporated the bladder wall, the procedure was converted to an open approach to perform the remainder of the reduction; however the robot was reintroduced for mesh placement. Post-operatively, the patient experienced mild incisional abdominal pain with return of bowel function on day four and was discharged that same day.

2.
J Phys Chem Lett ; 14(38): 8548-8554, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37724876

RESUMO

Anion-templated silver nanoclusters are fascinating to study because of their diverse structures, which are dictated by the nature of both anions and ligands. Here, we used the bulky 1-ethynyladamantane as one of the protecting ligands alongside trifluoracetate to successfully synthesize a chlorine-templated silver nanocluster─Cl@Ag19(C12H15)11(C2O2F3)7. Elucidation of its structure by single crystal X-ray diffraction revealed the structure to be a chlorine-centered Ag19 cage with protection by alkynyl and carboxylic ligands. This cluster is non-emissive at room temperature and showed green emission with a large Stokes shift at low temperature. The crystal structure was found to be quasi-isomeric with a previously reported Ag19 cluster protected by tert-butyl acetylene, which is emissive at room temperature. Detailed photoluminescence studies and structure-property correlation revealed that the arrangement of the silver skeleton which is influenced by the bulky substituent of the ligand might be responsible for the difference in emission properties.

3.
Sci Total Environ ; 859(Pt 1): 160140, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36379328

RESUMO

Carbon dioxide (CO2) is the top contributor to global warming. On the other, soot particles formed during fuel combustion and released into the atmosphere are harmful and also contribute to global warming. It would therefore be highly advantageous to capture soot and make use of it as a feedstock to synthesize carbon-based materials for applications such as carbon dioxide adsorption. In this work, flame-made diesel soot nanoparticles were used to produce a variety of activated carbons by combined oxidative treatment with hydrogen peroxide (H2O2) and potassium hydroxide (KOH), and their performance towards CO2 adsorption was evaluated. The effect of the chemical activation of soot with H2O2 for different reaction times and with KOH on the physicochemical properties of the activated carbons was investigated and compared to fresh soot. Interestingly, hollow aggregates of carbonaceous nanoparticles of a high interplanar distance, reduced polycyclic aromatic hydrocarbons (PAH) size, shorter PAH stacks, mesoporous structure, and a high content of oxygen functionalities along with other structural defects in PAHs were obtained in the synthesized activated carbons. Among the various analysis techniques employed, Raman spectroscopy indicated that the ID/IG ratio in soot decreased after simultaneous chemical treatment, though it did not indicate any enhancement in the graphitic character since the carbonyl and carboxylic containing PAHs and monovacancies (which cause defects in PAHs) also contribute to the increase in the intensity of the graphitic band. The activated carbons possessed promising CO2 adsorption capacities, adsorption kinetics and CO2/N2 selectivity. For example, one of the activated carbons, following H2O2 treatment for 9 h and a subsequent KOH activation, exhibited a CO2 adsorption capacity of 1.78 mmol/g at 1 bar and 25 °C, representing an increase of 161 % in capacity as compared to fresh soot. Hollow aggregates of carbonaceous nanoparticles consisting of shorter PAHs with a larger number of defects led to enhanced CO2 adsorption rate and CO2/N2 selectivity on activated carbons.


Assuntos
Dióxido de Carbono , Hidrocarbonetos Policíclicos Aromáticos , Dióxido de Carbono/análise , Fuligem , Peróxido de Hidrogênio/análise , Adsorção , Carvão Vegetal/química , Hidrocarbonetos Policíclicos Aromáticos/análise
4.
ACS Omega ; 5(42): 27083-27093, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33134668

RESUMO

In this study, the effect of accelerated ultraviolet (UV) aging on the properties of polypropylene (PP) as well as its blend with PP-graft-maleic anhydride (PP-g-MA) and composite with amine-functionalized mullite nanofibers (AMNF) was compared. Solid-state NMR exhibited some changes in the macromolecular chain structure after aging, whereas the formation of degradation products was confirmed through Fourier transform infrared (FTIR) spectroscopy. The aged composite was observed to exhibit the least increment in the crystallinity from X-ray and differential scanning calorimetry (DSC) analyses (0.3 and 0.5%, compared to 9.7 and 10.4%, respectively, for PP) owing to the stability of its amorphous phase against degradation. Similar resistance toward degradation was also confirmed by thermogravimetric analysis (TGA). The surface morphology of the materials also exhibited the lowest extent of surface embrittlement as well as a small number of shallow cracks in the case of a-PP/PP-g-MA/AMNF composite. The aged composite had a much higher impact strength of 14.9 kJ m-2 compared to 2.5 kJ m-2 for aged PP, thus exhibiting its stability against degradation owing to a synergistic combination of the filler and compatibilizer. The optimal performance of the composite was further confirmed through the least extent of reduction in the tensile strength and elongation at break. These findings demonstrate the superior performance of AMNF-reinforced PP composite over PP for outdoor applications.

5.
Oper Neurosurg (Hagerstown) ; 19(2): 190-194, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31872248

RESUMO

BACKGROUND: The use of frameless stereotactic robotic technology has rapidly expanded since the Food and Drug Administration's approval of the Robotic Surgical Assistant (ROSA) in 2012. Although the use of the ROSA robot has greatly augmented stereotactic placement of intracerebral stereoelectroencephalography (sEEG) for the purposes of epileptogenic focus identification, the preoperative planning stages remain limited to computer software. OBJECTIVE: To describe the use of a 3-dimensionally (3D)-printed patient model in the preoperative planning of ROSA-assisted depth electrode placement for epilepsy monitoring in a pediatric patient. METHODS: An anatomically accurate 3D model was created and registered in a preoperative rehearsal session using the ROSA platform. After standard software-based electrode trajectory planning, sEEG electrodes were sequentially placed in the 3D model. RESULTS: Utilization of the 3D-printed model enabled workflow optimization and increased staff familiarity with the logistics of the robotic technology as it relates to depth electrode placement. The rehearsal maneuvers enabled optimization of patient head positioning as well as identification of physical conflicts between 2 electrodes. This permitted revision of trajectory planning in anticipation of the actual case, thereby improving patient safety and decreasing operative time. CONCLUSION: Use of a 3D-printed patient model enhanced presurgical positioning and trajectory planning in the placement of stereotactic sEEG electrodes for epilepsy monitoring in a pediatric patient. The ROSA rehearsal decreased operative time and increased efficiency of electrode placement.


Assuntos
Procedimentos Cirúrgicos Robóticos , Criança , Eletrodos Implantados , Eletroencefalografia , Humanos , Impressão Tridimensional , Tecnologia , Estados Unidos
6.
Oper Neurosurg (Hagerstown) ; 19(1): 94-97, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31586195

RESUMO

BACKGROUND: The use of frameless stereotactic robotic technology has rapidly expanded since the Food and Drug Administration's approval of the Robotic Surgical Assistant (ROSA™) in 2012. Although the safety and accuracy of the ROSA platform has been well-established, the introduction of complex robotic technology into an existing surgical practice poses technical and logistical challenges particular to a given institution. OBJECTIVES: To better facilitate the integration of new surgical equipment into the armamentarium of a thriving pediatric neurosurgery practice by describing the use of a three-dimensional (3D)-printed patient model with in situ 3D-printed tumor for presurgical positioning and trajectory optimization in the stereotactic biopsy of a pontine lesion in a pediatric patient. METHODS: A 3D model was created with an added silicone mock tumor at the anatomical position of the lesion. In a preoperative rehearsal session, the patient model was pinned and registered using the ROSA platform, and a mock biopsy was performed targeting the in Situ silicone tumor. RESULTS: Utilization of the 3D-printed model enabled workflow optimization and increased staff familiarity with the logistics of the robotic technology. Biopsy trajectory successfully reached intralesional tissue on the 3D-printed model. The rehearsal maneuvers decreased operative and intubation time for the patient and improved operative staff familiarity with the robotic setup. CONCLUSION: Use of a 3D-printed patient model enhanced presurgical positioning and trajectory planning in the biopsy of a difficult to reach pontine lesion in a pediatric patient. The ROSA rehearsal decreased operative time and increased staff familiarity with a new complex surgical equipment.


Assuntos
Neurocirurgia , Procedimentos Cirúrgicos Robóticos , Criança , Humanos , Imageamento Tridimensional , Procedimentos Neurocirúrgicos , Impressão Tridimensional , Estados Unidos
7.
J Tissue Eng ; 9: 2041731418811183, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30542597

RESUMO

The purpose of this study was to characterize rat adipose-derived stem cells, induce adipose-derived stem cell tenogenesis, and analyze adipose-derived stem cell effects on tendon repair in vivo. Adipose-derived stem cells demonstrated an immunomodulatory, pro-angiogenic, and pro-proliferatory profile in vitro. Tenogenesis was induced for 1, 7, 14, and 21 days with 24 combinations of growth differentiation factor-5, 6, and 7 and platelet-derived growth factor-BB. Adipose-derived stem cells expression of scleraxis and collagen type I increased the most after 14 days of induction with growth differentiation factor-6 and platelet-derived growth factor-BB. Achilles excision defects injected with hydrogel alone (Gp2), with undifferentiated (Gp3) adipose-derived stem cells, or tenogenically differentiated (Gp4) adipose-derived stem cells exhibited improved tissue repair compared with untreated tendons (Gp1). Addition of adipose-derived stem cells improved tissue cytoarchitecture and increased expression of collagen type I and III, scleraxis, and tenomodulin. Adipose-derived stem cells significantly improved biomechanical properties (ultimate load and elastic toughness) over time more than hydrogel alone, while tenogenically differentiated adipose-derived stem cells improved the mean histological score and collagen fiber dispersion range closest to normal tendon. In addition, tendon sections treated with GFP-adipose-derived stem cells exhibited green fluorescence and positive GFP immunostaining on microscopy confirming the in vivo survival of adipose-derived stem cells that were injected into tendon defects to support the effects of adipose-derived stem cells on tissue up to 4.5 weeks post injury.

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