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1.
J Vasc Surg ; 80(2): 554-563.e4, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38608967

RESUMO

OBJECTIVE: Vascular graft and endograft infections (VGEIs) are complicated by high morbidity, mortality, and recurrence rates, notably due to biofilm formation on the graft surface, hardly dislodgeable by the sole anti-infectious treatment. The characteristics of this biofilm are still poorly documented. The aim of this study was to evaluate ex vivo biofilm on removed infected vascular grafts and endografts (VGEs). METHODS: Explanted VGEs were prospectively collected from 2019 to 2022 at Bordeaux University Hospital, France. Two samples per graft were used for scanning electron microscopy imaging; one was sonicated, and both grafts' sides were imaged. RESULTS: A total of 26 patients were included, 18 with VGEI, eight without any infection (endoleak and/or thrombosis), and 29 VGEs were collected. Microbial documentation was obtained in 83% of VGEIs. A thick layer of fibrin was visible on almost all grafts, mixed with a dense biofilm matrix on infected grafts visible as early as 1 month after the onset of infection. Bacteria were not always visualized on infected grafts' surface (80% on outer side and 85% on luminal side) but were surprisingly present on one-third of non-infected grafts. There was no significant difference between biofilm, fibrin, and microorganisms' distribution between the two grafts' sides. However, there were clear differences between infected and non-infected grafts, since immune cells, bacteria and biofilm were more frequently visualized on both sides of infected grafts (P < .05). Bacteria and immune cells although still visible, were significantly less present after sonication; the number of other elements including biofilm was not significantly different. CONCLUSIONS: The persistence of a thick layer of fibrin and biofilm embedding microorganisms on both sides of infected VGE even after 1 month of infection could be the explanation for the low success rates of conservative management and the usual need for graft removal to treat VGEIs.


Assuntos
Biofilmes , Implante de Prótese Vascular , Prótese Vascular , Microscopia Eletrônica de Varredura , Infecções Relacionadas à Prótese , Humanos , Infecções Relacionadas à Prótese/microbiologia , Infecções Relacionadas à Prótese/cirurgia , Prótese Vascular/efeitos adversos , Biofilmes/crescimento & desenvolvimento , Feminino , Masculino , Idoso , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/efeitos adversos , Estudos Prospectivos , Pessoa de Meia-Idade , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/efeitos adversos , Remoção de Dispositivo , França , Fatores de Tempo , Idoso de 80 Anos ou mais , Bactérias/isolamento & purificação
2.
Exp Eye Res ; 239: 109762, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38147936

RESUMO

The vitreous humor (VH) is a hydrophilic, jelly-like ocular fluid, which is located in the posterior chamber of the eye. The rheological, structural, and chemical properties of VH change significantly during aging, which further causes eye-associated diseases and could be a potential indicator for various diseases. In this study, artificial VH (A-VH) samples were created by taking into account different age groups to observe age-related changes in the physicochemical properties of these samples. This study aimed to measure the physicochemical properties of age-dependently prepared A-VH samples to determine the changes with aging in the physicochemical properties of A-VH samples. Phosphate-buffered saline (PBS)-based A-VH samples were prepared in three types representing adult, middle-aged, and elder individuals. Age-related changes in physicochemical properties (surface tension, osmolality, pH, relative viscosity, density, and refractive index) were analyzed by related equipment. The A-VH samples, prepared using PBS, showed strong similarity to authentic VH in terms of physicochemical properties. While the age-related changes studies have revealed some discrepancies between age-dependently prepared A-VH samples in terms of surface tension, osmolality, relative viscosity, and pH with high correlation coefficients (r2 > 0,94), density and refractive index values did not show any significant differences and correlation between types of A-VH representing 3 age groups. In conclusion, age-dependent A-VH samples were created successfully to use ex vivo method development studies, and the influence of aging on the physicochemical properties of VH was demonstrated as well.


Assuntos
Oftalmopatias , Corpo Vítreo , Adulto , Pessoa de Meia-Idade , Humanos , Idoso , Corpo Vítreo/química , Envelhecimento
3.
Heart Vessels ; 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39438335

RESUMO

Radiofrequency (RF) catheter ablation is a well-established therapeutic approach for treating arrhythmias, where lesion size and safety are critical for efficacy. This study explored the impact of varying irrigation flow rates on lesion characteristics using the TactiFlex™ SE Ablation Catheter (TF) in an ex vivo porcine heart model, focusing on the size and safety outcomes associated with low versus standard flow rates. Myocardial slabs from porcine hearts were subjected to ablation using two types of irrigated catheters. Lesion formation was compared between low (8 mL/min for TF) and standard irrigation flow rates (13 mL/min for TF) across different power settings (30, 40, and 50 W). Outcome measures included lesion dimensions, incidence of steam pops, and impedance drops. A total of 210 lesions were generated under various settings. At low flow rates, the TF catheter safely formed larger lesions compared to the standard flow rates without a significant increase in steam pops or impedance drops. Lesions at low flow rates were comparable in size to those formed using other catheters under the standard settings. Conversely, the standard flow settings for TF produced smaller lesions but exhibited higher safety profiles, as evidenced by fewer steam pops and impedance drops. Lower irrigation flow rates using a TF catheter can achieve larger lesions without compromising safety, offering an optimization strategy for RF ablation procedures that balances efficacy and safety. These findings may guide clinicians in tailoring ablation strategies according to individual patient needs.

4.
Int J Mol Sci ; 25(3)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38338900

RESUMO

Cystinosis is a low-prevalence lysosomal storage disease. The pathomechanism involves abnormal functioning of the cystinosine lysosomal cystine transporter (CTNS), causing intraliposomal accumulation of the amino acid cysteine disulfide, which crystallizes and deposits in several parts of the body. The most common ophthalmic complication of cystinosis is the deposition of "gold dust" cystine crystals on the cornea, which already occurs in infancy and leads to severe photosensitivity and dry eyes as it gradually progresses with age. In the specific treatment of cystinosis, preparations containing cysteamine (CYA) are used. The availability of commercialized eyedrops for the targeted treatment is scarce, and only Cystadrops® are commercially available with strong limitations. Thus, magistral CYA-containing compounded eyedrops (CYA-CED) could have a key role in patient care; however, a rationally designed comprehensive study on the commercialized and magistral products is still missing. This work aims to build up a comprehensive study about commercialized and magistral CYA eye drops, involving pharmacokinetic and physicochemical characterization (applying mucoadhesivity, rheology test, investigation of drug release, and parallel artificial membrane permeability assays), as well as ex vivo tests, well supported by statistical analysis.


Assuntos
Cistinose , Humanos , Cistinose/metabolismo , Cisteamina/uso terapêutico , Cisteamina/metabolismo , Cistina/metabolismo , Soluções Oftálmicas/uso terapêutico , Córnea/metabolismo
5.
Exp Eye Res ; 231: 109471, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37086963

RESUMO

The pristine Human Amniotic Membrane (HAM) has portrayed outstanding potential as scaffold for ocular surface reconstruction and regeneration. However, in treatment procedures where the supporting membrane matrix of HAM is not obligatory and only the bioactive molecules are vital, the surgical practise of HAM grafting causes redundant trauma and economic burden to the patient. Hence, in our laboratory we have attempted to break down HAM to nanoscale particles and validate its potential as a competent ocular therapeutic agent; by conducting a comparative analysis between the fresh, lyophilized, micronized and Nanonized Amniotic Membrane (NAM) particles. Our results evidently showcased that the prepared NAM particles was <100 nm and the major biomolecules such as collagen and hyaluronic acid were well retained. Further, the NAM particles eluted significantly higher amounts of proteins and growth factors while maintaining its stability and isotonicity when stored at 4 °C. Its biostability was assayed in the presence of lysozyme enzyme. Its remarkable ability to promote cell proliferation in rabbit corneal cells and negative cytotoxicity is an added advantage for ocular application. The ocular biocompatibility of NAM, evaluated by the ex vivo assessment of corneal thickness, transparency, histopathology, immunohistochemistry and corneal permeability clearly indicated its suitability for ophthalmic applications.


Assuntos
Âmnio , Córnea , Animais , Humanos , Coelhos , Colágeno
6.
Molecules ; 28(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37175328

RESUMO

Different parts of Ficus religiosa are the common components of various traditional formulations for the treatment of several blood disorders. The new-fangled stem buds' powder was extracted with 80% ethanol and successively fractionated by chloroform and methanol. Chloroform and methanol fractions of Ficus religiosa (CFFR and MFFR) were tested for antiplatelet, antithrombotic, thrombolytic, and antioxidant activity in ex vivo mode. The MFFR was particularly investigated for GC-MS and toxicity. The antiplatelet activity of the CFFR, MFFR, and standard drug aspirin at 50 µg/mL was 54.32%, 86.61%, and 87.57%, and a significant delay in clot formation was noted. CFFR at different concentrations did not show a significant effect on the delay of clot formation, antiplatelet, and free radical scavenging activity. The most possible marker compounds for antiplatelet and antioxidant activity identified by GC-MS in the MFFR are salicylate derivatives aromatic compounds such as benzeneacetaldehyde (7), phenylmalonic acid (13), and Salicylic acid (14), as well as Benzamides derivatives such as carbobenzyloxy-dl-norvaline (17), 3-acetoxy-2(1H)-pyridone (16), and 3-benzylhexahydropyrrolo [1,2-a] pyrazine-1,4-dione (35). A toxicity study of MFFR did not show any physical indications of toxicity and mortality up to 1500 mg/kg body weight and nontoxic up to 1000 mg/kg, which is promising for the treatment of atherothrombotic diseases.


Assuntos
Fibrinolíticos , Ficus , Fibrinolíticos/farmacologia , Fibrinolíticos/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Metanol , Antioxidantes/farmacologia , Clorofórmio , Cromatografia Gasosa-Espectrometria de Massas
7.
Int J Comput Dent ; 26(1): 11-18, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35072426

RESUMO

AIM: The aim of the present ex vivo study was to examine the accuracy of augmented reality-assisted apicoectomies (AR-A) versus template-guided apicoectomies (TG-A). MATERIALS AND METHODS: In total, 40 apicoectomies were performed in 10 cadaver pig mandibles. Every pig mandible underwent two AR-A and two TG-A in molar and premolar teeth. A crossed experimental design was applied. AR-A was performed using Microsoft HoloLens 2, and TG-A using SMOP software. Postoperative CBCT scans were superimposed with the presurgical planning data. The deviation between the virtually planned apicoectomy and the surgically performed apicoectomy was measured. The primary (angular deviation [degrees]) and secondary (depth deviation [mm]) outcome parameters were measured. RESULTS: Overall, 36 out of 40 apicoectomies could be included in the study. Regarding the primary outcome parameter (angular deviation), there was no significant difference between AR-A and TG-A. The mean values were 5.33 degrees (± 2.96 degrees) in the AR-A group, and 5.23 degrees (± 2.48 degrees) in the TG-A group. The secondary outcome parameter (depth deviation) showed no significant difference between the AR-A group of 0.27 mm (± 2.32 mm) and the TG-A group of 0.90 mm (± 1.84 mm). In this crossed experimental design, both techniques overshot the target depth in posterior sites, as opposed to not reaching the target depth in anterior sites (P < 0.001). CONCLUSION: Augmented reality (AR) technology has the potential to be introduced into apicoectomy surgery in case further development is implemented.


Assuntos
Realidade Aumentada , Cirurgia Assistida por Computador , Animais , Suínos , Apicectomia , Software , Mandíbula/cirurgia , Dente Molar
8.
Acta Vet Hung ; 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36037048

RESUMO

The objective of the present pilot study was to determine the force required to break (a) intact canine tibiae, (b) tibiae following the osteotomy of the tibial tuberosity and (c) tibiae following Tibial Tuberosity Advancement- (TTA-) rapid surgery. Six pairs of tibiae of dogs between 15 and 35 kg body weight were used in a cadaver study. Three groups were created with four tibiae in each group; intact (Group 1), osteotomy of the tibial tuberosity and tibial crest (Group 2) and TTA-rapid (Group 3). The tibiae were put under static axial compressive load, applied until failure. The force required to break the tibiae was termed maximal force (F max). The mean of F max was 8193.25 ± 2082.84 N in Group 1, 6868.58 ± 1950.44 N in Group 2 and 7169.71 ± 4450.39 N in Group 3. The sample size was small for a statistical analysis but as a preliminary result, we have determined the force (F max) required to break canine tibiae. Furthermore, we hypothesise that osteotomies result in weakening of the tibial structure.

9.
Haemophilia ; 27(3): 488-493, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33780101

RESUMO

OBJECTIVES: Early detection of bleeding into a joint is crucial in patients with haemophilia. This study was designed to evaluate the sensitivity of ultrasonography (USG) and magnetic resonance imaging (MRI) to detect the presence of blood in small concentrations in a simulated model to mimic joint bleeding. MATERIALS AND METHODS: Different concentrations of blood in plasma, varying from 0.1% to 45%, were collected in 10-ml plastic syringes and imaged using 12 and 18 MHz USG transducers and with 1.5T and 3T MRI scanners, at different intervals of time following dilution. The images were scored for the presence of blood by four experienced radiologists who were blinded to the concentration of blood. RESULTS: Within the first 2 h, the 18 MHz transducer was able to detect blood consistently up to 0.5%, whereas the 12 MHz transducer could consistently identify blood up to 1.4%. After the first 12 h, both transducers were able to detect blood up to 0.5% concentration. However, at concentrations below 0.5%, there was discordance in the ability to detect blood, with both transducers. There was no correlation between the signal intensities of MRI images and concentration of blood, at different time intervals, irrespective of the magnetic field strength. CONCLUSIONS: Detection of blood using the USG is dependent on variables such as the concentration of blood, frequency of the transducer used and timing of the imaging. As the concentration of blood decreases below 0.5%, the discordance between the observers increases, implying that the detection limit of USG affects its reliability at lower concentrations of blood. Caution is urged while interpreting USG imaging studies for the detection of blood in symptomatic joints.


Assuntos
Hemartrose , Hemofilia A , Hemofilia A/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Reprodutibilidade dos Testes , Ultrassonografia
10.
Microbiol Immunol ; 65(8): 325-332, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33930208

RESUMO

Antibiotic resistance is a snowballing international threat. Some of the antibiotics have lost their effectiveness due to overuse and underuse. Thus, there is an urgent need to tackle this global challenge, either by inhibiting the resistance mechanisms or by the development of new chemical entities. Thus, in the current study, the antibacterial activity of selected phytomolecules was investigated against bacterial strains, alone and in combination, with standard drugs. The antibacterial potential of these phytomolecules was explored using in vitro assays (microtiter assay, bacterial growth kinetics, percentage retardation of growth, and antimicrobial synergy study) and in vivo studies (zebrafish infection model). In vitro and in vivo studies have shown promising antibacterial effects against, both, Gram-positive and Gram-negative bacteria. Moreover, a cell viability assay also indicated the cytoprotective effect of these phytomolecules in combination with standard antibiotics (SABX). Thus, these phytomolecules could be a promising broad-spectrum antibacterial agent in combination with standard antibiotics.


Assuntos
Antibacterianos/farmacologia , Animais , Antibacterianos/uso terapêutico , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos , Peixe-Zebra
11.
Sensors (Basel) ; 21(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205567

RESUMO

The ability to predict heat transfer during hyperthermal and ablative techniques for cancer treatment relies on understanding the thermal properties of biological tissue. In this work, the thermal properties of ex vivo liver, pancreas and brain tissues are reported as a function of temperature. The thermal diffusivity, thermal conductivity and volumetric heat capacity of these tissues were measured in the temperature range from 22 to around 97 °C. Concerning the pancreas, a phase change occurred around 45 °C; therefore, its thermal properties were investigated only until this temperature. Results indicate that the thermal properties of the liver and brain have a non-linear relationship with temperature in the investigated range. In these tissues, the thermal properties were almost constant until 60 to 70 °C and then gradually changed until 92 °C. In particular, the thermal conductivity increased by 100% for the brain and 60% for the liver up to 92 °C, while thermal diffusivity increased by 90% and 40%, respectively. However, the heat capacity did not significantly change in this temperature range. The thermal conductivity and thermal diffusivity were dramatically increased from 92 to 97 °C, which seems to be due to water vaporization and state transition in the tissues. Moreover, the measurement uncertainty, determined at each temperature, increased after 92 °C. In the temperature range of 22 to 45 °C, the thermal properties of pancreatic tissue did not change significantly, in accordance with the results for the brain and liver. For the three tissues, the best fit curves are provided with regression analysis based on measured data to predict the tissue thermal behavior. These curves describe the temperature dependency of tissue thermal properties in a temperature range relevant for hyperthermia and ablation treatments and may help in constructing more accurate models of bioheat transfer for optimization and pre-planning of thermal procedures.


Assuntos
Hipertermia Induzida , Encéfalo , Temperatura Alta , Fígado , Pâncreas , Temperatura , Condutividade Térmica
12.
Drug Dev Ind Pharm ; 46(9): 1458-1467, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32729728

RESUMO

The present study was designed to prepare dapagliflozin (DFG) loaded ternary solid dispersions (SDs) using the carrier blend polyethylene glycol 6000 (PEG 6000) and poloxamer 188 (PLX 188). The prepared DFG-SDs were evaluated for solubility study, physicochemical characterization and molecular simulation study. The prepared DFG-SDs showed significant higher solubility and dissolution vis-a-vis pure DFG and DFG physical mixture. The composition DFG:PEG:PLX (1:2.25:0.75 mM) showed the highest solubility (0.476 ± 0.016 mg/mL). The physicochemical characterization confirms the polymorphic transition of DFG from crystalline state to stable amorphous form. The prepared DFG-SDs showed a significantly higher dissolution (64.78 ± 2.34% to 78.41 ± 2.39%) than pure DFG (15.70 ± 3.54%). DFG-SD2 showed a significantly enhanced drug permeation (p<.05) (58.76 ± 4.65 µg/cm) as compared to pure DFG (14.97 ± 3.32 µg/cm). The molecular docking study result revealed a good hydrophobic interaction of DFG with the used carrier due to the lowest energy pose. The interaction occurs between the methylene bridges and the central hydrophobic chain of polyoxypropylene of the polymer. Therefore, DFG-SDs prepared by microwave irradiation method using hydrophilic carrier blend might be a promising strategy for improving the solubility and in vitro dissolution performance.


Assuntos
Compostos Benzidrílicos/química , Glucosídeos/química , Poloxâmero , Polietilenoglicóis , Portadores de Fármacos , Simulação de Acoplamento Molecular , Polietilenoglicóis/química , Solubilidade
13.
Drug Dev Ind Pharm ; 46(2): 264-271, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32000536

RESUMO

Topical drug delivery for local anesthetics has been an interesting area of research for formulators considering the resistance and barrier properties of skin and high clearance rate of drugs like prilocaine and lidocaine (duration of action < 2.5 h). In this study, efforts have been made to sustain the release of prilocaine and lidocaine by using depot microemulsion system. Drug loaded microemulsions were formulated using Capmul MCM, Pluronic F127, polyethylene glycol 200 (PEG 200) and water from pseudo-ternary diagrams. The Smix at 1:4 ratio showed larger microemulsion area in comparison to 1:2 ratio. The ex-vivo studies indicate sustained release of prilocaine and lidocaine from the microemulsion up to 8 h, in comparison to 4 h with ointments. Skin irritation study on rabbits confirmed the safety of drug loaded microemulsions for local drug delivery. The improved ex vivo data is reflected in the in vivo studies, were radiant heat tail-flick test and sciatic nerve model showed prolong duration of action for both prilocaine and lidocaine microemulsions in comparison to ointment. The in vitro and in vivo efficacy of prilocaine and lidocaine was non-significant. The improved efficacy was due to high penetration of microemulsion and depot effect due to local precipitation (destabilization of microemulsion) of drug in the skin layer. The sustained local anesthetic effect is highly desirable for the treatment of skin irritation due to skin burns and pre- and post-operative pain.


Assuntos
Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Emulsões/química , Lidocaína/administração & dosagem , Lidocaína/química , Prilocaína/administração & dosagem , Prilocaína/química , Administração Cutânea , Anestésicos Locais/administração & dosagem , Anestésicos Locais/química , Animais , Química Farmacêutica/métodos , Diglicerídeos/química , Sistemas de Liberação de Medicamentos/métodos , Cabras , Monoglicerídeos/química , Poloxâmero/química , Polietilenoglicóis/química , Coelhos , Ratos , Ratos Wistar , Pele/metabolismo , Absorção Cutânea
14.
Knee Surg Sports Traumatol Arthrosc ; 27(6): 1953-1964, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30387000

RESUMO

PURPOSE: Osteochondral implants are currently adopted for the treatment of symptomatic full-thickness chondral and osteochondral defects. Agili-C™ is a cell-free aragonite-based scaffold which aims to reproduce the original structure and function of the articular joint while directing the growth and regeneration of both cartilage and its underlying subchondral bone. The goal of the present study was to investigate the ex vivo mechanisms of action (MOA) of the Agili-C™ implant in the repair of full-thickness cartilage defects. In particular, we tested whether Agili-C™ implant has the potential to stimulate cartilage ingrowth through chondrocytes migration into the 3D interconnected porous structure of the scaffold, along with maintaining their viability and phenotype and the deposition of hyaline cartilage matrix. METHODS: Articular cartilage samples were collected through the Gift of Hope Organ and Tissue Donor Network (Itasca, IL) within 24 h from death. For this study, cartilage from a total of 14 donors was used. To model a chondral defect, donut-shaped cartilage explants were prepared from each tissue specimen. The chondral phase of the Agili-C™ implant was placed inside the tissue in full contact and press fit manner. Cartilage explants with the Agili-C™ implant inside were cultured for 60 days. As a control, the same donut-shaped cartilage explants were cultured without Agili-C™, under the same culture conditions. RESULTS: Using fresh human cadaveric articular cartilage tissue in a 60-day culture, it was demonstrated that chondrocytes were able to migrate into the Agili-C™ scaffold and contribute to the deposition of the extracellular matrix (ECM) rich in collagen type II and aggrecan, and lacking collagen type I. Additionally, we were able to show the formation of a layer populated by progenitor-like cells on the articular surface of the implant. CONCLUSIONS: The analysis of samples taken from knee and ankle joints of human donors with a wide age range and both genders supports the potential of Agili-C™ scaffold to stimulate cartilage regeneration and repair. Based on these results, the present scaffold can be used in the clinical practice as a one-step procedure to treat full-thickness chondral defects.


Assuntos
Doenças das Cartilagens/cirurgia , Cartilagem Articular/citologia , Condrócitos/transplante , Articulação do Joelho/cirurgia , Próteses e Implantes , Adulto , Idoso , Animais , Doenças das Cartilagens/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Cultura de Tecidos , Alicerces Teciduais
15.
Dig Endosc ; 30(6): 719-729, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29846982

RESUMO

Cancer is one of the major causes of death in both the USA and Europe. Molecular imaging is a novel field that is revolutionizing cancer management. It is based on the molecular signature of cells in order to study the human body both in normal and diseased conditions. The emergence of molecular imaging has been driven by the difficulties associated with cancer detection, particularly early-stage premalignant lesions which are often unnoticed as a result of minimal or no structural changes. Endoscopic surveillance is the standard method for early-stage cancer detection. In addition to recent major advancements in endoscopic instruments, significant progress has been achieved in the exploration of highly specific molecular probes and the combination of both will permit significant improvement of patient care. In this review, we provide an outline of the current status of endoscopic imaging and focus on recent applications of molecular imaging in gastrointestinal, hepatic and other cancers in the context of detection, targeted therapy and personalized medicine. As new imaging agents have the potential to broadly expand our cancer diagnostic capability, we will also present an overview of the main types of optical molecular probes with their pros and cons. We conclude by discussing the challenges and future prospects of the field.


Assuntos
Endoscopia , Imagem Molecular , Neoplasias/diagnóstico por imagem , Humanos , Neoplasias/terapia
16.
J Endovasc Ther ; 24(1): 35-46, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27659155

RESUMO

PURPOSE: To test and validate magnetic resonance imaging (MRI) sequences for peripheral artery lesion characterization and relate the MRI characteristics to the amount of force required for a guidewire to puncture peripheral chronic total occlusions (CTOs) as a surrogate for immediate failure of endovascular therapy. METHODS: Diseased superficial femoral, popliteal, and tibial artery segments containing 55 atherosclerotic lesions were excised from the amputated limbs of 7 patients with critical limb ischemia. The lesions were imaged at high resolution (75 µm3 voxels) with T2-weighted (T2W) and ultrashort echo time (UTE) sequences on a 7-T MR scanner. The MR images (n=15) were validated with micro-computed tomography and histology. CTOs (n=40) were classified by their MR signal characteristics as "soft" (signals indicating fat, thrombus, microchannels, or loose fibrous tissue), "hard" (collagen and/or speckled calcium signals), or "calcified" (calcified nodule signals). A 2-kg load cell advanced the back end of a 0.035-inch stiff guidewire at a fixed displacement rate (0.05 mm/s) through the CTOs, and the forces required to cross each lesion were measured. RESULTS: T2W images showed fat as hyperintense and hardened tissue as hypointense. Calcium and thrombus appeared as a signal void in conventional MRI sequences but were easily identified in UTE images (thrombus was hyperintense and calcium hypointense). MRI accurately differentiated "hard," "soft," and "calcified" CTOs based on associated guidewire puncture force. The guidewire could not enter "calcified" CTOs (n=6) at all. "Hard" CTOs (n=9) required a significantly higher (p<0.001) puncture force of 1.71±0.51 N vs 0.43±0.36 N for "soft" CTOs (n=25). CONCLUSION: MRI characteristics of PAD lesions correlate with guidewire puncture forces, an important aspect of crossability. Future work will determine if clinical MR scanners can be used to predict success in peripheral vascular interventions.


Assuntos
Procedimentos Endovasculares , Artéria Femoral/diagnóstico por imagem , Imageamento por Ressonância Magnética , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Placa Aterosclerótica , Artéria Poplítea/diagnóstico por imagem , Artérias da Tíbia/diagnóstico por imagem , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/terapia , Idoso , Idoso de 80 Anos ou mais , Tomada de Decisão Clínica , Feminino , Artéria Femoral/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Doença Arterial Periférica/patologia , Artéria Poplítea/patologia , Valor Preditivo dos Testes , Punções , Reprodutibilidade dos Testes , Artérias da Tíbia/patologia , Calcificação Vascular/patologia
17.
Pharm Dev Technol ; 22(4): 617-626, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27574791

RESUMO

Clotrimazole (CTZ) is a broad spectrum antimycotic agent known to be very effective locally for the treatment of fungal skin infections. The aim of this study was to study the effect of chitosan-coated microemulsion (CME) for topical delivery of CTZ and also evaluate its in vitro antifungal efficacy, ex vivo permeation and retention ability on the skin surface. The pseudo-ternary phase diagrams were developed using clove oil as oil phase, Tween 80 and propylene glycol as surfactant and co-surfactant, respectively, and distilled water as aqueous phase. CME was prepared by the drop wise addition of chitosan solution to the optimized microemulsion. Physicochemical parameters (globule size, zeta potential, drug content, viscosity and pH) and in vitro release of CME were studied. The in vitro antifungal efficacy of CME and ME was studied by cup-plate method against Candida albicans. Ex vivo drug permeation study was also carried out in a modified diffusion cell, using rat skin. The developed CME displayed an average globule size less than 50 nm and a positive surface charge, acceptable physico-chemical behavior, and exhibited sustained drug release in in vitro study. In in vitro anti-fungal study, CME showed greater values of zone of inhibition as compared to ME due to its prolonged action as well as fungistatic nature of chitosan. In ex vivo study, CME showed better retention and sustained permeation property than ME due to the mucoadhesive property of chitosan. These results suggest that positively charged CMEs could be used as novel topical formulation for its ability to retain on the skin and its ability to sustain the release of the drug.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Anti-Infecciosos Locais/farmacocinética , Quitosana/química , Clotrimazol/administração & dosagem , Clotrimazol/farmacocinética , Emulsões/química , Administração Cutânea , Animais , Anti-Infecciosos Locais/farmacologia , Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candidíase/tratamento farmacológico , Clotrimazol/farmacologia , Tamanho da Partícula , Transição de Fase , Ratos Wistar
18.
Nanomedicine (Lond) ; 19(15): 1369-1388, 2024 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900630

RESUMO

Aim: Our investigation aims to estimate the antifungal effect of propranolol hydrochloride (PNL). Methods: Oleosomes (OLs) were fabricated by thin-film hydration and evaluated for entrapment efficiency (EE%), particle size (PS), polydispersity index (PDI), zeta potential (ZP), and amount of drug released after 6 h Q6h (%). Results: The optimal OL showed a rounded shape with optimum characteristics. The ex-vivo permeation and confocal laser scanning microscopy verified the prolonged release and well deposition of PNL-loaded OLs-gel. The in-silico assessment demonstrated the good stability of PNL with OLs' ingredients. In vivo evaluations for PNL-loaded OLs-gel showed a good antifungal impact against Candida albicans with good safety. Conclusion: This work highlights the potential of PNL-loaded OLs-gel as a potential treatment for candida vaginal infection.


[Box: see text].


Assuntos
Antifúngicos , Candida albicans , Quitosana , Hidrogéis , Propranolol , Candida albicans/efeitos dos fármacos , Propranolol/química , Propranolol/farmacologia , Propranolol/administração & dosagem , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/administração & dosagem , Feminino , Animais , Quitosana/química , Hidrogéis/química , Tamanho da Partícula , Humanos , Liberação Controlada de Fármacos , Lipossomos/química , Candidíase Vulvovaginal/tratamento farmacológico , Candidíase Vulvovaginal/microbiologia , Portadores de Fármacos/química , Vagina/microbiologia , Vagina/efeitos dos fármacos
19.
J Biomed Mater Res B Appl Biomater ; 112(3): e35394, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433621

RESUMO

Kaempferol (KMP) belong to flavonoid class have developed in ethosomal formulation and were evaluated for their potential to treat diabetic foot ulcers. Even though ethosomes are highly deformable, they can pass through human skin intact. KMP ethosomes were formulated using the cold method and optimized by Box-Behnken design (BBD) (three-factor, three-level (33 )). The formulation variables used for optimization are drug concentration of KMP, soylecithin content, and ethanol percentage. The optimized formulation was examined using transmission electronic microscopy (TEM), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, in-vitro release, ex-vivo permeation studies, and storage stability. The optimized KMP ethosomes was found to have vesicle size (VS) of 283 ± 0.3 nm and zeta potential (ZP) of -29.67 ± 0.3 mV, polydispersity index (PDI) of 0.36, % entrapment efficiency (%EE) of 91.02 ± 0.21%, drug loading (%) of 46.23 ± 2.5% followed by good storage stability at 4°C/60 ± 5% RH. In vitro drug release of optimized KMP ethosomes was 88.2 ± 2.75%, which was approximately double when compared with pure KMP release, that is 49.9 ± 1.89%. The release kinetics for optimized KMP ethosomes follows the Korsmeyer-Peppas model. An apparent permeation coefficient of 356.25 ± 0.5 µg/cm2 was determined and compared with pure KMP (118.46 ± 0.3 µg/cm2 ) for 24 h. According to the study, ethosomes can be a cutting-edge strategy that offers a new delivery method for prolonged and targeted distribution of KMP in a variety of dosage forms including oral, topical, transdermal, and so forth.


Assuntos
Etanol , Quempferóis , Humanos , Quempferóis/farmacologia , Varredura Diferencial de Calorimetria , Liberação Controlada de Fármacos , Cinética
20.
Front Cell Dev Biol ; 10: 1026477, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684440

RESUMO

The main objective of the current research work was to synthesize mesoporous silica nanoparticles for controlled delivery of mometasone furoate for potential nasal delivery. The optimized sol-gel method was used for the synthesis of mesoporous silica nanoparticles. Synthesized nanoparticles were processed through Zeta sizer, SEM, TEM, FTIR, TGA, DSC, XRD, and BET analysis for structural characterization. The in vitro dissolution test was performed for the inclusion compound, while the Franz diffusion experiment was performed for permeability of formulation. For the determination of expression levels of anti-inflammatory cytokines IL-4 and IL-5, RNA extraction, reverse transcription, and polymerase chain reaction (RT-PCR) were performed. The MTT assay was also performed to determine cell viability. Synthesized and functionalized mesoporous silica nanoparticles showed controlled release of drugs. FT-IR spectroscopy confirmed the presence of the corresponding functional groups of drugs within mesoporous silica nanoparticles. Zeta sizer and thermal analysis confirmed the delivery system was in nano size and thermally stable. Moreover, a highly porous system was observed during SEM and TEM evaluation, and further it was confirmed by BET analysis. Greater cellular uptake with improved permeability characteristics was also observed. As compared to the crystalline drug, a significant improvement in the dissolution rate was observed. It was concluded that stable mesoporous silica nanoparticles with significant porosity were synthesized, efficiently delivering the loaded drug without any toxic effect.

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