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1.
Front Pharmacol ; 14: 1213824, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37521476

RESUMEN

The revolution of biomedical applications has opened new avenues for nanotechnology. Zinc Chromium vanadate nanoparticles (VCrZnO4 NPs) have emerged as an up-and-coming candidate, with their exceptional physical and chemical properties setting them apart. In this study, a one-pot solvothermal method was employed to synthesize VCrZnO4 NPs, followed by a comprehensive structural and morphological analysis using a variety of techniques, including X-Ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, Energy-dispersive X-ray, and X-ray photoelectron spectroscopy. These techniques confirmed the crystallinity of the NPs. The VCrZnO4 NPs were tested for their antibacterial activity against primary contaminants such as Enterobacteriaceae, including Shigella flexneri, Salmonella cholerasis, and Escherichia coli, commonly found in hospital settings, using the broth dilution technique. The results indicated a stronger antibacterial activity of VCrZnO4 NPs against Shigella and Salmonella than E. coli. Electron microscopy showed that the NPs caused severe damage to the bacterial cell wall and membrane, leading to cell death. In addition, the study evaluated the anticancer activities of the metal complexes in vitro using colorectal cancer cells (HCT-116) and cervical cancer cells (HELA), along with non-cancer cells and human embryonic kidney cells (HEK-293). A vanadium complex demonstrated efficient anticancer effects with half-inhibitory concentrations (IC50) of 38.50+3.50 g/mL for HCT-116 cells and 42.25+4.15 g/mL for HELA cells. This study highlights the potential of Zinc Chromium vanadate nanoparticles as promising candidates for antibacterial and anticancer applications. Various advanced characterization techniques were used to analyze the properties of nanomaterials, which may help develop more effective and safer antibacterial and anticancer agents in the future.

2.
Med Biol Eng Comput ; 60(11): 3057-3068, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36063352

RESUMEN

Anesthesia drug overdose hazards and lack of gold standards in anesthesia monitoring lead to an urgent need for accurate anesthesia drug detection. To investigate the PPG waveform features affected by anesthesia drugs and develop a machine-learning classifier with high anesthesia drug sensitivity. This study used 64 anesthesia and non-anesthesia patient data (32 cases each), extracted from Queensland and MIMIC-II databases, respectively. The key waveform features (total area, rising time, width 75%, 50%, and 25%) were extracted from 16,310 signal recordings (5-s duration). Discriminant analysis, support vector machine (SVM), and K-nearest neighbor (KNN) were evaluated by splitting the dataset into halve training (11 patients, 8570 segments) and halve testing dataset (11 patients, 7740 segments). Significant differences exist between PPG waveform features of anesthesia and non-anesthesia groups (p < 0.05) except total area feature (p > 0.05). The KNN classifier achieved 91.7% (AUC = 0.95) anesthesia detection accuracy with the highest sensitivity (0.88) and specificity (0.90) as compared to other classifiers. Kohen's kappa also shows almost perfect agreement (0.79) with the KNN classifier. The KNN classifier trained with significant PPG features has the potential to be used as a reliable, non-invasive, and low-cost method for the detection of anesthesia drugs for depth analysis during surgical operations and postoperative monitoring.


Asunto(s)
Algoritmos , Fotopletismografía , Humanos , Aprendizaje Automático , Monitoreo Fisiológico/métodos , Fotopletismografía/métodos , Máquina de Vectores de Soporte
3.
Dermatol Res Pract ; 2022: 7238905, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36590106

RESUMEN

Background: Solar radiations that reach the Earth can be divided into ultraviolet, visible light, and infrared. Overexposure to these radiations can facilitate adverse skin diseases such as sunburn, skin cancer, and photoaging. People who drive vehicles for an extended period are likely to develop skin cancer in the exposed body area. Method: This research proposes a wearable protective device around the upper arm to measure the transmitted radiation through the front and the side windows. A novel skin type classification algorithm using a color sensor was created to provide an accurate skin type identification. Also, the device was programmed to calculate the time before sunburn occurrence based on the ultraviolet index, sunscreen's sun protection factor, and skin type. Results: The prototype was tested inside a Toyota Camry model 2001 vehicle with an accuracy of 97%. The front window had transmitted more infrared radiation compared to the side window. The highest recorded value was 76.76 mW/cm2. On the other hand, the side window had transmitted more ultraviolet compared to the front window as it lacks the protective polyvinyl butyral layer that the front window has. The highest recorded ultraviolet index was 3.5. Conclusion: These results highlight the importance of wearing the designed solar band and using appropriate UV and IR protection while driving a vehicle to prevent skin diseases from occurring.

4.
Photodermatol Photoimmunol Photomed ; 38(1): 44-52, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34157181

RESUMEN

BACKGROUND: Solar radiations are classified in terms of wavelengths, including visible light, infrared, and ultraviolet. Infrared radiation (IR) accounts the largest proportion of solar radiations that cause oxidative stress-induced aging of human skin. This study investigates the biochemical changes in proteins, lipids, and DNA associated with acute exposure to IR radiations. METHOD: In vivo confocal Raman spectroscopy was used to examine the forearms region of 20 healthy participants with phototype II skin, aged between 18 and 30 years, without IR incidence (T0), with IR incidence 30 minutes (T30) at day 1 and 30 minutes at day 2 (T60). One-way ANOVA and two-tailed t test along with post hoc Bonferroni correction were used to detect the existence of significant differences in the timestamps of stratum corneum, stratum basale, and dermis at all IR wavenumbers under test. RESULTS: An increase in the Raman peaks of stratum corneum lipids, decrease in stratum basal DNA peaks, and a shift in the amide I peak of collagen in the skin dermis were observed. One-way ANOVA results showed significant differences among timestamps of stratum corneum, stratum basale, and dermis at all wavenumbers under test (P < .001). Furthermore, paired timestamps also showed significant differences (P < .016) except at two wavenumbers 1293 cm-1 and 852 cm-1 in stratum corneum and basale layer clusters on timestamps (T0 & T30 and T30 & T60, P > .016). This study proved that confocal Raman spectroscopy is an useful technique for early evaluation of IR-induced skin changes.


Asunto(s)
Piel , Espectrometría Raman , Adolescente , Adulto , Dermis , Epidermis , Humanos , Rayos Infrarrojos , Adulto Joven
5.
Photodermatol Photoimmunol Photomed ; 37(2): 140-152, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33095927

RESUMEN

BACKGROUND: Skin aging is a dynamic process that affects the entire body, marked by molecular and structural changes. Type I collagen is the most abundant structural component and accounts 80% of total collagen in human skin. The amount of proline and hydroxyproline reflect the quantity and quality of the collagen fiber in the extracellular matrix of skin, which is alerted due to accumulated effects of intrinsic and extrinsic aging. Extrinsic aging is driven by ultraviolet radiation-induced reactive oxygen species production that activates the matrix metalloproteinase and disrupts the extracellular matrix of skin dermis, while intrinsic aging is the non-enzymatic process resulting in advanced glycation end products (AGEs). In the presence of pentosidine-AGEs, aging process is accelerated. METHOD: In vivo Raman spectra of human dermis were collected from forearms of 30 volunteers and were divided into three groups: 10 young adult 25 ± 5 years, 10 old adult 65 ± 10 years and 10 diabetic old adult 65 ± 10 years old male participants. Density functional theory was performed to compute the vibration modes of AGEs, pentosidine, and glucosepane. RESULTS: In vivo confocal Raman spectroscopy detects the specific changes in the proline and hydroxyproline conformation, collagen fiber degradation of type I collagen and AGE protein contribution to specific Raman bands in the aged dermis because of Intrinsic and Extrinsic aging. Statistical t test marked significant differences (P < .01) in Raman peaks of proline and hydroxyproline among young adult, old adult, and diabetic old adult participants at wavenumbers 855, 875, 922, and 938 cm-1 . CONCLUSION: In vivo confocal Raman spectroscopy is a useful tool to detect the AGE markers in the old adult and diabetic old adult male participants, which interacts with the ultraviolet radiations and accelerates the aging process resulting in the extracellular matrix degradation.


Asunto(s)
Matriz Extracelular/metabolismo , Envejecimiento de la Piel , Espectrometría Raman/métodos , Adolescente , Adulto , Anciano , Niño , Colágeno/metabolismo , Diabetes Mellitus/metabolismo , Femenino , Productos Finales de Glicación Avanzada/metabolismo , Humanos , Hidroxiprolina/metabolismo , Masculino , Prolina/metabolismo
6.
Photodermatol Photoimmunol Photomed ; 36(4): 278-289, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32187717

RESUMEN

BACKGROUND: Ultraviolet radiations (UV) absorbed by the skin can drive photochemical reactions which range from sunburn to skin cancer. The repeated exposure to Infrared radiations (IR) induces the heat into the skin, which causes dehydration and erythema as an immediate effect. This heat activates the metalloproteinase enzyme that reduces the number of procollagen and collagen fibers in the dermal skin, which results premature skin aging. This work aims to design a protective measure in order to avoid these damages. METHOD: The proposed protective measure is a wristwatch with an alert alarm which can sense UV and IR radiations. Whenever UV/IR radiation levels exceed beyond the defined limits, alarm will be activated that warns the user to apply protective measures. These radiations are detected by SI1145 digital UV Index/IR/visible light sensor and assigned, using Arduino, to an appropriate UV index and IR radiation levels. RESULTS: The IR and UV readings were recorded several times and at four different hours through the day. The readings showed its highest value at 10 am and 2 pm, which are considered the highest sun intensity. The other readings were at 6 am and 5 pm and considered the least dangerous hours. CONCLUSION: The data collected from the sensor are used to program the alarm. To combine all components, a PCB and a prototype were designed and printed. The UV/IR wristwatch is applicable to alert the user from the continuous and accumulated harmful effects of the radiations and enable them to seek protective measures.


Asunto(s)
Diseño de Equipo , Enfermedades de la Piel/prevención & control , Rayos Ultravioleta/efectos adversos , Dispositivos Electrónicos Vestibles , Algoritmos , Diseño de Equipo/métodos , Humanos , Dosímetros de Radiación , Radiometría/instrumentación , Enfermedades de la Piel/etiología , Pigmentación de la Piel , Factores de Tiempo
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