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1.
Anal Sci ; 40(3): 413-427, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38170424

RESUMEN

The plant Saussurea Simpsoniana, which has been used in traditional medicine for its biocompatibility and abundant nutrients, offers a wide range of remedies. Local communities effectively utilize medicines derived from the plant's roots to treat various ailments such as bronchitis, rheumatic pain, and abdominal and nervous disorders. In this study, we present an elemental analysis of the chemical composition (wt%) of this medicinal plant using the laser-induced breakdown spectroscopy (LIBS) technique. In the air atmosphere, an Nd:YAG (Q-switched) laser operating at a wavelength of 532 nm is utilized to create plasma on the sample's surface. This laser has a maximum pulse energy of approximately 400 mJ and a pulse duration of 5 ns. A set of six miniature spectrometers, covering the wavelength range of 220-970 nm, was utilized to capture and record the optical emissions emitted by the plasma. The qualitative analysis of LIBS revealed the presence of 13 major and minor elements, including Al, Ba, C, Ca, Fe, H, K, Li, Mg, Na, Si, Sr, and Ti. Quantitative analysis was performed using calibration-free laser-induced breakdown spectroscopy (CF-LIBS), ensuring local thermodynamical equilibrium (LTE) and optically thin plasma condition by considering plasma excitation temperature and electron number density. In addition, a comparison was made between the results obtained from CF-LIBS and those acquired through energy-dispersive X-ray spectroscopy (EDX) analysis.


Asunto(s)
Plantas Medicinales , Saussurea , Rayos Láser , Espectrometría por Rayos X , Semillas
2.
Polymers (Basel) ; 15(15)2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37571052

RESUMEN

The potential of using laser-induced breakdown spectroscopy (LIBS) in combination with various other spectroscopic and statistical methods was assessed for characterizing pure and MgO-doped nylon (6/6) organic polymer samples. The pure samples, obtained through a polycondensation chemical technique, were artificially doped with MgO prior to analysis for comparative purposes. These artificially doped samples served as crucial reference materials for comparative analysis and reference purposes. The LIBS studies were performed under local thermodynamic equilibrium (LTE) and optically thin plasma conditions. To assess the structural crystallinity of the nylon (6/6) polymer samples, X-ray diffraction (XRD) analysis, and Fourier transform infrared (FTIR) spectroscopy were employed to detect functional groups such as N-H, C-H, and C-N in the adsorbent polyamide nylon sample. Additionally, diffuse reflectance spectroscopy (DRS) analysis was conducted to investigate the effects of doping and temperature on the band gap and material reflectance across different sample temperatures. Chemical compositional analysis was performed using X-ray photoelectron spectroscopy (XPS) with the carbon C1s peak at 248.8 eV serving as a reference for spectrum calibration, along with energy-dispersive X-ray (EDX) analysis, which demonstrated good agreement between the techniques. To validate the different methodologies, the results obtained from CF-LIBS and EDX were compared with those from the standard inductively coupled plasma mass spectrometry (ICP-MS) technique. Finally, for classification analysis, principal component analysis (PCA) was applied to the LIBS spectral data at different sample temperatures (25 °C, 125 °C, 225 °C, and 325 °C). The analyses demonstrated that the combination of LIBS with PCA, along with other methods, presents a robust technique for polymer characterization.

3.
Heliyon ; 9(3): e13957, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36895409

RESUMEN

In the present study, the immediate detection of rare-earth elements (REEs) in phosphorite deposits has been reported using laser-induced breakdown spectroscopy (LIBS). Numerous emission lines corresponding to the REEs such as lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm), and ytterbium (Yb), have been detected in the emission spectra of phosphorite-induced plasma plume. For the quantitative analysis, we employed the calibration-free LIBS (CF-LIBS), and Energy Dispersive X-ray (EDX) spectroscopy techniques. The results obtained using the CF-LIBS technique show excellent agreement with that obtained by EDX. Besides principal component analysis (PCA) was employed by incorporating the LIBS spectral data of rare earth phosphorite rocks samples containing La, Ce, Nd, Sm, and Yb emission lines. The first three PCs were observed using LIBS spectral data set showing a covariance (interpretation rate) up to 76.3%. This study suggests that LIBS yields a quick and very reliable qualitative and quantitative analysis of REEs in any geological ore sample.

4.
Polymers (Basel) ; 14(17)2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-36080765

RESUMEN

The laser-induced breakdown spectroscopy (LIBS) technique was performed on polymers to study the neutral and ionic emission lines along with the CN violet system (B2Σ+ to X2Σ+) and the C2 Swan system (d3 Пg-a3 Пu). For the laser-based emission analyses, the plasma was produced by focusing the laser beam of a Q-switched Nd: YAG laser (2ω) at an optical wavelength of 532 nm, 5 ns pulse width, and a repetition frequency of 10 Hz. The integration time of the detection system was fixed at 1-10 ms while the target sample was positioned in air ambiance. Two organic polymers were investigated in this work: nylon and nylon doped with ZnO. The molecular optical emission study of nylon and doped nylon polymer sample reveals CN and C2 molecular structures present in the polymer. The vibrational emission analysis of CN and C2 bands gives information about the molecular structure of polymers and dynamics influencing the excitation structures of the molecules. Besides, it was further investigated that the intensity of the molecular optical emission structure strongly depends on the electron number density (cm-3), excitation temperature (eV), and laser irradiance (W/cm2). These results suggest that LIBS is a reliable diagnostic technique for the study of polymers regarding their molecular structure, identification, and compositional analysis.

5.
Molecules ; 27(15)2022 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-35956998

RESUMEN

We report a quantitative analysis of various plant-biochar samples (S1, S2 and S3) by utilizing a laser-induced breakdown spectroscopy (LIBS) technique. For LIBS analysis, laser-induced microplasma was generated on the target surface by using a focused beam through a high-power Nd: YAG laser and optical emission spectra were recorded using a charged coupled device (CCD) array spectrometer, with wavelength ranges from 200 nm to 720 nm. The spectroscopical analysis showed the existence of various ingredients, including H, Li, Ca, Na, Al, Zn, Mg, Sr, Si, and Fe, along with a CN molecular emission band due to B2Σ+ - X2Σ+ electronic transition. By assuming conditions of the plasma is optically thin and in LTE, calibration-free laser-induced breakdown spectroscopy (CF-LIBS) was utilized for the compositional analysis of the ingredients present in the three plant-biochar samples. To lower the uncertainties, we used an average composition (%) of the three plant-biochar samples. The quantitative study of the plant-biochar samples was also achieved using the energy dispersive X-ray (EDX) technique, showing good agreement with the CF-LIBS technique. In addition, statistical analysis, such as principal component analysis (PCA), was performed for the clustering and classification of the three plant-biochar samples. The first three PCs explained an overall ~91% of the variation in LIBS spectral data, including PC1 (58.71%), PC2 (20.9%), and PC3 (11.4%). These findings suggest that LIBS is a robust tool for rapid measurement of heavy as well as light elements, such as H, Li, and nutritional metals in plant-biochar samples.


Asunto(s)
Carbón Orgánico , Rayos Láser , Nutrientes , Análisis Espectral/métodos
6.
Molecules ; 27(12)2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35744877

RESUMEN

In this work, we report the results of the compositional analysis of an aluminum gallium arsenide (AlGaAs) sample using the calibration-free laser-induced breakdown spectroscopy (CF-LIBS) technique. The AlGaAs sample was doped with three various concentrations of gallium (Ga), arsenic (As), and aluminum (Al), as reported by the manufacturer, and the CF-LIBS technique was employed to identify the doping concentration. A pulsed Q-switched Nd: YAG laser capable of delivering 200 and 400 mJ energy at 532 and 1064 nm, respectively, was focused on the target sample for ablation, and the resulting emission spectra were captured using a LIBS 2000+ spectrometer covering the spectral range from 200 to 720 nm. The emission spectra of the AlGaAs sample yielded spectral lines of Ga, As, and Al. These lines were further used to calculate the plasma parameters, including electron temperature and electron number density. The Boltzmann plot method was used to calculate the electron temperature, and the average electron temperature was found to be 5744 ± 500 K. Furthermore, the electron number density was calculated from the Stark-broadened line profile method, and the average number density was calculated to be 6.5 × 1017 cm-3. It is further observed that the plasma parameters including electron temperature and electron number density have an increasing trend with laser irradiance and a decreasing trend along the plume length up to 2 mm. Finally, the elemental concentrations in terms of weight percentage using the CF-LIBS method were calculated to be Ga: 94%, Al: 4.77% and As: 1.23% for sample-1; Ga: 95.63%, Al: 1.15% and As: 3.22% for sample-2; and Ga: 97.32%, Al: 0.69% and As: 1.99% for sample-3. The certified concentrations were Ga: 95%, Al: 3% and As: 2% for sample-1; Ga: 96.05%, Al: 1% and As: 2.95% for sample-2; and Ga: 97.32%, Al: 0.69% and As: 1.99% for sample-3. The concentrations measured by CF-LIBS showed good agreement with the certified values reported by the manufacturer. These findings suggest that the CF-LIBS technique opens up an avenue for the industrial application of LIBS, where quantitative/qualitative analysis of the material is highly desirable.

7.
J Long Term Eff Med Implants ; 29(1): 37-43, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31679200

RESUMEN

Available bone is one of the important factors in implant treatments. Due to concerns about complications caused by less bone implant contact area, researchers have focused on biomechanical properties of implants and methods to promote them. We investigated stress distribution around bone of different implant diameters and vertical cantilever length. Computed tomography (CT) images obtained of human mandible were used in this study. An SPI implant (Alpha Bio Tech, Simplantology) of two different lengths (10.5 mm and 8.5 mm) and two different widths (3.5 mm and 4.5 mm) were placed into two different groups of bone samples (with and without osteoplasty). Vertical and lateral forces of 100N and 30N at 45° were applied simultaneously in two models. The stress was analyzed using the finite element method. Maximum stress areas were located around the implant neck. Lower stress values in the loaded implants were observed in the shorter group related to the increase in crown height space, when compared to the other group. A wider implant may be better to dissipate force, thus reducing stress on the bone surrounding the implant. Additionally, the use of shorter and wider implants might be a reasonable alternative in sites limited by the height of the residual ridge.


Asunto(s)
Proceso Alveolar , Implantes Dentales , Diseño de Prótesis Dental , Mandíbula , Estrés Mecánico , Proceso Alveolar/diagnóstico por imagen , Fenómenos Biomecánicos , Simulación por Computador , Módulo de Elasticidad , Análisis de Elementos Finitos , Humanos , Mandíbula/diagnóstico por imagen , Tomografía Computarizada por Rayos X
15.
Tumour Biol ; 37(5): 5765-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26206498

RESUMEN

MicroRNAs (miRNAs) have a large number of various target genes in different cancer types, which may result in many biological functions. Thus, identifying the molecular mechanisms of miRNAs may effect on the complexity of cancer progression via regulation of gene. In the current study, we utilized real-time PCR to quantify the diction of miR-148b in trail hepatocellular carcinoma (HCC) specimen and normal tissues. Furthermore, we evaluated the relationship of miR-148b and clinicopathological features with survival of HCC patients. Therefore, we evaluated the level of miR-148b expression in 101 HCC patients and also in 40 normal control cases. The result suggested lower expression in tumor tissues than normal control tissues (0.96 ± 0.14; 1.84 ± 0.20, P < 0.05). Our findings suggest that the declined expression of miR-148b can considerably be linked to tumor node metastasis (TNM) stage (stages III and IV; P = 0.021) and vein invasion (P = 0.029). Nevertheless, miR-148b expression was not related to sex (P = 0.674), age (P = 0. 523), size of tumor (P = 0.507), liver cirrhosis, and histologic grade (P = 0.734). Survival analysis showed that low expression was remarkably related to overall survival (P = 0.012). Furthermore, multivariate survival test suggested that decline of miR-148b diction was linked to poor survival in HCC patients. Our results suggested that miR-148b is decreased in HCC. Therefore, we concluded that miR-148b may play its role in the prognosis of HCC.

16.
Diagn Pathol ; 10: 135, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26248880

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide, mainly due to its high rates of postoperative recurrence and metastasis. Please remove, it currently ranks as the third most common cause of cancer-related deaths. MiRNAs are a set of small, single-stranded, non-coding RNA molecules that negatively regulate gene expression at the post-transcriptional level. In this study, we demonstrated the down-regulation of miR-148a in HCC and non-cancerous tissues using qRT-PCR. METHODS: Ninety six HCC samples and their noncancerous normal liver tissues were collected. Total mRNA including miRNA was extracted, and miR-148a expression was determined using qRT-PCR. Furthermore, the correlation between the miR-148a expression and clinicopathological parameters was investigated. RESULTS: The result showed that reduction of miR-148a expression was associated with TNM stage, metastasis, and number of tumor nodes. Multivariate Cox proportional hazards model analysis showed that low expression of miR-148a was independently associated with recurrence of HCC in the current study. Moreover, our result showed that lower expression in tumor tissues in comparison with corresponding normal control tissues. CONCLUSION: Down-regulation of miR-148a is related to HCC carcinogenesis and deterioration of HCC. MicroRNA-148a may act as a suppressor miRNA of HCC, and it is therefore a potential prognostic biomarker for HCC patients.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/genética , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias Hepáticas/genética , MicroARNs/biosíntesis , Adulto , Anciano , Área Bajo la Curva , Biomarcadores de Tumor/análisis , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Regulación hacia Abajo , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/mortalidad , Pronóstico , Curva ROC , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
Diagn Pathol ; 10: 85, 2015 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-26134399

RESUMEN

BACKGROUND: Platelet-rich plasma (PRP) contains numerous growth factors to promote wound healing and angiogenesis. The aim of this study was to gain further information about the benefits of platelet-rich-plasma for healing cutaneous acute to chronic wounds. METHODS: A total of 30 New Zealand albino rabbits (n = 15/group) were randomly assigned to two experimental groups: control group, and PRP group. Bilateral resection defects measuring 3 cm were surgically created on the dorsolateral of the cutaneous in animals and the defects were randomly divided into two mentioned groups. Wound area, neovascularization, size and epithelialization were compared on days 7, 14 and 21 post-wounding. Histopathological analyses were conducted on 15 specimens from each group after sacrifice by the cellular aspects of the regeneration of the tissue. RESULTS: Our results were indicated that the wound area of PRP was smaller than that in the non-treated group on days 7, 14 and 21. Furthermore, a significant decrease of the wound size was observed in PRP groups that were significantly greater than that in the control group. A significant increase of the mean vascular density was noted in the PRP treated groups compared to the control groups at day 14 and especially day 21. This results indicated that PRP treated group' enhanced angiogenesis at the wound beds as compared to no treatment group. CONCLUSION: These results could be useful for researchers in the growing fields of tissue repair and experimental wound healing. Further studies will be essential to determine the role of PRP in clinical practice.


Asunto(s)
Proteínas Angiogénicas/sangre , Péptidos y Proteínas de Señalización Intercelular/sangre , Plasma Rico en Plaquetas/metabolismo , Piel/patología , Cicatrización de Heridas , Heridas Penetrantes/terapia , Animales , Enfermedad Crónica , Modelos Animales de Enfermedad , Femenino , Masculino , Neovascularización Fisiológica , Conejos , Repitelización , Piel/lesiones , Piel/metabolismo , Factores de Tiempo , Heridas Penetrantes/sangre , Heridas Penetrantes/patología
18.
Diagn Pathol ; 10: 74, 2015 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-26088761

RESUMEN

BACKGROUND: Hypercholesterolemia is associated with an increased risk of heart disease. In this study, we investigated the antihyperlipidemic effects of garlic (Allium sativum L.) in rat models of hypercholesterolemic. METHODS: Wistar male rats were randomly divided into 4 diet groups with garlic supplementation. Male Wistar rats were fed by standard pellet diet (group I), standard diet supplemented with 4% garlic (group II), lipogenic diet (containing sunflower oil, cholesterol and ethanol) equivalent to 200 mg raw garlic/kg body weight (raw) (group III) and lipogenic diet equivalent to 400 mg raw garlic/kg body weight (raw) (group IV). RESULTS: Rats fed 400 g/kg garlic extract(GE), had a significantly lower concentration of serum low-density lipoprotein cholesterol (LDL-C) cholesterol and elevated HDL -C cholesterol at day 28 (P < 0.05).In addition,serum levels of LDL-C was lower in the III and IV group than those in the IV group (P < 0.001 for each). However, cholesterol efflux capacity was positively correlated with HDL cholesterol concentration (P < 0 · 0001). It was also directly correlated with garlic supplementation (P < 0 · 0001). CONCLUSION: Together Taken, the results are clearly indicative of the beneficial effects of garlic in reducing lateral side effects of hyperlipidemia. Our data demonstrate that GE has protective effects on HDL in rats with high LDL intake. Therefore, it could be used to remedy hypercholesterolemia with help reduce risk of coronary heart disease VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1834155749171141.


Asunto(s)
Colesterol en la Dieta , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Ajo , Hipercolesterolemia/tratamiento farmacológico , Hipolipemiantes/farmacología , Extractos Vegetales/farmacología , Animales , Biomarcadores/sangre , Modelos Animales de Enfermedad , Hipercolesterolemia/sangre , Hipercolesterolemia/etiología , Masculino , Raíces de Plantas , Ratas Wistar , Factores de Tiempo
19.
Diagn Pathol ; 10: 23, 2015 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-25884935

RESUMEN

BACKGROUND: Gout is a metabolic disorder that results in hyperuricemia and the deposition of positively birefringent monosodium urate crystals in various parts of the body. The purpose of this study was to characterize the incidence and diagnostic features of visceral gout found at necropsy in two patients. CASE PRESENTATION: The authors present an unusual report of untreated gout leading to major structure destructions in visceral organs. Gross post-mortem examination revealed a white powdery substance and display needle-like crystalline symmetry under the macroscopic on the visceral surfaces. Microscopically, the presence of crystalline deposits (urate tophi) were detected in visceral organs, such as; kidney, liver, lung and mesentery. Irrespective of its location, gout was observed, by H&E, as intracellular and extracellular eosinophilic deposits that compressed surrounding tissues. Moreover, numerous necrotizing granulomas of multifarious sizes were observed that were compounded by large aggregations of eosinophilic material (gout), surrounded by epithelioid macrophages, lymphoplasmacytic cells, foreign body multinucleated giant cells, fibrosis, fibroplasia and few edema. On the other hand, our results revealed that granulomatous nodules in the mesentery and kidney contained large numbers of gout foci compared with lung and liver. Furthermore, the immediate cause of death in these cases were not identified, but appeared to result from multiple factors, including the visceral gout due to unsuitable environmental conditions. CONCLUSION: In summary, we have identified a valid histopathologic damage index for use in laboratory studies of visceral gout. This system provides a feasible method of representing visceral damage in gout, and may allow for better understanding of the natural history, pathophysiology and the management of acute attacks of gouty visceral in this disease. Finally, to the best of our knowledge, understanding of the distribution of monosodium urate crystals within the body can aid clinical diagnosis and further understanding of the resulting pathology. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1293547351151638 .


Asunto(s)
Elapidae , Gota/patología , Ácido Úrico/análisis , Vísceras/patología , Animales , Animales de Laboratorio , Autopsia , Biopsia , Causas de Muerte , Cristalización , Gota/metabolismo , Granuloma/patología , Necrosis , Vísceras/química
20.
Diagn Pathol ; 10: 19, 2015 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-25889956

RESUMEN

BACKGROUND: The present study sought to investigate the effects of Tarantula cubensis extract (TC; Theranekron®) on the histopathological scores of peritoneal wound healing after laparotomy in the rats. METHODS: This study was designed to investigate the effects of Theranekron on the peritoneal wound healing after wound creation, on days9, 14, 19, 24 and 29 post-injury in rats. Twenty-four mature Wister-albino male rats were randomly divided into two groups. In the experimental group, TC was repeatedly injected subcutaneously (SC) over the lesion 9, 14,19 and 24 days after laparotomy, whereas the control group received only normal saline by subcutaneous injection and then the animal groups were euthanized9, 14, 19, 24, and 29 days after wounding respectively by intravenous injections of pentobarbital (50 mg/kg). Finally, assessment of the peritoneal wound healing between the groups was carried out by histopathologic data and statistical tests as Mann-Whitney U, Wilcoxon W and Z RESULTS: Histopathological examination indicated significant improvement in angiogenesis, re-epithelialization and less inflammatory response in comparison to control and also, revealed matured, compact and parallel deposition of collagen fibrils on day 29. So, at long term, treatment reduced the inflammation and increased the quality and rate of wound re- epithelialization compared to controls(P < 0.05). Furthermore, excluding the control group, rats exhibited the most pronounced effect on wound closure, with the statistically significant improvement in wound healing being seen at post-operative day 29. Moreover, collagen content on days 24 and 29 in the test group was found to be higher than in the healthy group. To warp up, treated groups had a significant increase in peritoneal wound healing area compared to the control group on all days (P < 0.05). CONCLUSIONS: Our results suggested that Theranekron have delivered a novel therapeutic route for wound treatment in clinical practice. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2958770714954315 .


Asunto(s)
Antiinflamatorios/farmacología , Peritoneo/efectos de los fármacos , Sustancias Protectoras/farmacología , Venenos de Araña/farmacología , Cicatrización de Heridas/efectos de los fármacos , Heridas y Lesiones/tratamiento farmacológico , Inductores de la Angiogénesis/farmacología , Animales , Antiinflamatorios/administración & dosificación , Colágeno/metabolismo , Modelos Animales de Enfermedad , Esquema de Medicación , Inyecciones Subcutáneas , Masculino , Neovascularización Fisiológica/efectos de los fármacos , Peritoneo/irrigación sanguínea , Peritoneo/metabolismo , Peritoneo/patología , Peritoneo/cirugía , Sustancias Protectoras/administración & dosificación , Ratas Wistar , Repitelización/efectos de los fármacos , Venenos de Araña/administración & dosificación , Factores de Tiempo , Heridas y Lesiones/metabolismo , Heridas y Lesiones/patología , Heridas y Lesiones/fisiopatología
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