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1.
Nanotechnology ; 34(1)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36195011

RESUMO

Heterostructure BiVO4/Bi2O3nanocomposites with enhanced visible light activity are effectively synthesized through an easiest and single step hydrothermal route, using bismuth subnitrate and ammonium meta-vanadate as main raw materials in existence of citric acid. The phase and surface structure, topography and optical properties of synthesized composites are characterized by XRD, SEM, EDX, FTIR, UV-Visible and PL spectroscopy. It was found that 5%BiVO4/Bi2O3(BOBV-5) nanocomposite exhibit excellent photocatalytic performance for rhodamine B dye degradation and tetracyclic under irradiation of visible light as compared to single component i.e. BiVO4. The increased photocatalytic activity should be ascribed for making p-n heterojunction among p-type Bi2O3and n-type BiVO4. This p-n heterojunction successfully reduce the recombination of photogenerated charge carriers. Furthermore, the BOBV-5 novel photocatalyst shows good stability in constructive five cycles and photocatalytic activity is best for conquering photo corrosion of a photocatalysts. To explain charge migration route, whole photocatalytic mechanism was described in terms of energy band structures. Furthermore, the present work is helpful effort for design of new visible light photocatalytic materials with heterojunction structures.

2.
Nanotechnology ; 29(38): 385501, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-29933247

RESUMO

The current work explores the excitation of surface plasmon polaritons (SPPs) on a one dimensional (1D) silver nano-grating device, simulated on glass substrate, which can sense a very small change in the refractive index of an analyte adjacent to it. The most recent modeling technique finite element analysis is applied in this work by using a COMSOL RF module. The models of 1D grating devices of different slit widths with fixed periodicity and film thickness are simulated. The data is collected and then used to study higher refractive index unit per nanometer (RIU/nm) as well as the effect of the widths of the slits on the RIU. A number of investigations are done by the simulated data, like a dip in the transmission spectra of p-polarized light. This dip is due to SPP resonance with the variation of slit width. Furthermore, the most fascinating part of the research is the COMSOL modeling that provides an opportunity to look into factors affecting higher RIU/nm, while visualizing the cross-sectional view of the grating device and strong electric field enhancement at the surface of the metallic device. When the slit width is almost equal to half of the periodicity of the grating device, SPP resonance increases and it is at maximum for the slit width equal to two-thirds of the periodicity, because the coupling efficiency is at maximum.

3.
Heliyon ; 9(5): e15978, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37215909

RESUMO

Bismuth Vanadate (BiVO4) has been synthesized using simple hydrothermal technique while varying the pH of concentrated H2SO4. With the increase of pH values (from 06 to 10), the morphology of the synthesized material tuned in the form of nano-spheres and cubes in the range from 50 to 60 nm. The lateral affect tuned the bandgap of BiVO4 from 2.47 eV to 2.50 eV which is significant in the context of present study. It is worth mentioning that desirous bandgap corresponds to the visible spectrum of the solar light being abundantly available and finds many applications in real life. The synthesized nanomaterial BiVO4 has been characterized through UV-Vis spectroscopy, X-ray diffraction, Scanning electron microscope and energy-dispersive X-ray (EDX) spectroscopy. The synthesized BiVO4 has been tested as photocatalyst for degradation of industrial pollutant from Leather Field Industry. Said catalyst (BiVO4) successfully degraded the industrial pollutant after 3 h under solar light irradiation. Therefore, the BiVO4 can be regarded as potential photocatalyst for degradation of industrial waste which is highly needed.

4.
J Coll Physicians Surg Pak ; 25(9): 694-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26374369

RESUMO

Metastatic involvement of the optic nerve or its sheath is very rare (1.3 - 3%). The most common malignancies reported to metastasize to the optic nerve or its sheath are breast, lung, kidney, bladder, gastric and colorectal cancers. Carcinoma of uterine cervix metastatic to optic nerve and optic nerve sheath is extremely rare and is associated with grave prognosis due to underlying high tumor burden. Here in, we report a 61-year Saudi woman who was treated with concurrent chemoradiation for squamous cell carcinoma of cervix FIGO IVA 6 months back. She presented with pain and progressive visual loss in the right eye. Magnetic resonance imaging showed enhanced solid mass of the intraorbital optic nerve consistent with optic nerve sheath meningioma. Immunostaining (CK5/6, CAM 5.2, p63 and p16) confirmed the diagnosis of metastatic squamous cell carcinoma of uterine cervix.


Assuntos
Carcinoma de Células Escamosas/secundário , Meningioma/patologia , Bainha de Mielina/patologia , Neoplasias do Nervo Óptico/secundário , Neoplasias Uterinas/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Neoplasias Meníngeas/patologia , Pessoa de Meia-Idade , Segunda Neoplasia Primária/patologia
5.
Int Med Case Rep J ; 8: 127-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26203287

RESUMO

Skull base metastasis from differentiated thyroid carcinoma, including papillary and follicular thyroid carcinoma, is a rare manifestation. Herein, we present three cases of skull base metastasis of papillary thyroid carcinoma. The mean age of the patients was 68.6 (65-74) years, and the mean interval between initial diagnosis and skull base metastasis was 56.3 (28-89) months. Cranial nerve palsies were seen in all patients. Intensity modulated radiation therapy to deliver 6,000-6,600 cGy to the skull base metastasis was given to all patients, in addition to partial resection in one patient. At the time of last follow-up, all skull base metastases were well controlled.

6.
Int J Surg Case Rep ; 13: 91-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26177377

RESUMO

INTRODUCTION: We report a rare case of duodenal metastasis from primary lung adenocarcinoma presented with history of melena and weight loss. PRESENTATION OF CASE: A 52-year-old smoker man presented with six months history of epigastric pain, melena and weight loss. Esophago-gastroduodenoscopy revealed a 10mm ulcerative lesion in the fourth part of duodenum. Histopathology of resected lesion showed poorly differentiated adenocarcinoma. Tumor cells showed immunopositivity for cytokeratin-7 (CK7), thyroid transcription factor 1 (TTF-1), and immunonegativity for CK20, Villin, CDX2 and thyroglobulin, supporting the diagnosis of metastatic adenocarcinoma of the lung origin. Computed tomography (CT) of chest revealed left hilar mass encasing the main pulmonary artery associated with ipsilateral hilar and contralateral mediastinal lymphadenopathy. Bronchoscopy assisted biopsy of lung mass confirmed the diagnosis of primary adenocarcinoma. Patient was staged as T4N3M1. After the resection of duodenal metastasis followed by three cycles of cisplatinum based chemotherapy with Bevacizumab, melena resolved completely. DISCUSSION: Duodenal metastases from lung adenocarcinoma are extremely uncommon, and rarely produce symptoms. Most of cases require duodenectomy or pancreatico-duodenectomy for symptomatic relief. For smaller duodenal metastatic lesions (≤1cm) endoscopic resection is a feasible therapeutic option. CONCLUSION: Although rare, duodenal metastasis from lung adenocarcinoma should also be included in the differential diagnosis of melena. Smaller lesions (≤1cm) can safely be managed with endoscopic resection.

7.
J Otolaryngol Head Neck Surg ; 44: 48, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26546329

RESUMO

INTRODUCTION: Age is an important prognostic factor in differentiated thyroid cancer (DTC). Our aim was to evaluate differences in clinicopathological features and treatment outcomes among children and adult patients with DTC. MATERIALS AND METHODS: We studied 27 children (below 18 years) with DTC treated during the period 2000-2012 and were compared with (a) 78 adults aged 19-25 years and (b) 52 adults aged 26-30 years treated during the same period in terms of their clinicopathological features and long term treatment outcomes. Locoregional recurrence (LRR), locoregional control (LRC), distant metastasis (DM), distant metastasis control (DMC), disease free survival (DFS) and overall survival (OS) rates were evaluated. RESULTS: Mean age of children was 13.5 years (range: 5-18), while mean age of adults was 24.6 years (range: 19-30). In children, female: male ratio was 2.85:1, and in adults female: male ratio was 7.1:1 (P = 0.041). No significant difference in tumor size was seen between the two groups (P = 0.653). According to American Thyroid Association (ATA) risk stratification classification, the children (85.2 %) were found to have at high risk as compared to adults P = 0.001. Post-thyroidectomy complications and RAI induced toxicities were observed more in children than adults (P = 0.043 and P = 0.041 respectively). LRR occurred in 6 (22.2 %), 9 (11.5 %) and 3 (5.8 %) in age groups of <18 years, 19-25 years and 26-30 years respectively (P = 0.032); while DM was seen in 10 (37.0 %), 9 (10.3 %) and 5 (9.6 %) in age groups of <18 years, 19-25 years and 26-30 years respectively (P = 0.002). Ten year DFS rates were 67.3 % in age group below 18 years, 82.4 % in age group of 19-25 years and 90.1 % in age group of 26-30 years (P = 0.021). CONCLUSION: At the time of diagnosis, children with DTC were found to have more aggressive clinicopathological characteristics. Comparatively lower LRC, DMC and DFS rates in children warrants further multi-institutional studies.


Assuntos
Estadiamento de Neoplasias , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Arábia Saudita/epidemiologia , Taxa de Sobrevida/tendências , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/cirurgia , Resultado do Tratamento , Adulto Jovem
8.
Arab J Gastroenterol ; 14(3): 133-4, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24206744

RESUMO

Skin and subcutaneous metastases are uncommon, and mostly originating from cancers of the breast, kidney, colon, lung, and melanoma. Oesophageal cancers rarely metastasise to the skin and subcutaneous soft tissue. Skin and subcutaneous metastases are associated with dismal prognosis. Only few related case reports have been published so far. In this report, we describe a 52year old patient with lower oesophageal adenocarcinoma who developed subcutaneous metastasis, 9months after neoadjuvant chemoradiation followed by trans-hiatal esophagectomy.


Assuntos
Adenocarcinoma/secundário , Neoplasias Esofágicas/patologia , Cuidados Paliativos , Neoplasias de Tecidos Moles/secundário , Tela Subcutânea , Adenocarcinoma/terapia , Quimiorradioterapia Adjuvante , Neoplasias Esofágicas/terapia , Esofagectomia , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasias de Tecidos Moles/terapia , Parede Torácica
9.
Case Rep Gastrointest Med ; 2013: 386263, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23607002

RESUMO

Introduction. Follicular variant (FV) papillary thyroid carcinoma (PTC) has aggressive biologic behavior as compared to classic variant (CV) of PTC and frequently metastasizes to the lungs and bones. However, metastasis to the pancreas is extremely rare manifestation of FV-PTC. To date, only 9 cases of PTC have been reported in the literature. Pancreatic metastases from PTC usually remain asymptomatic or manifest as repeated abdominal aches. Associated obstructive jaundice is rare. Prognosis is variable with reported median survival from 16 to 46 months. Case Presentation. Herein we present a 67-year-old Saudi woman, who developed pancreatic metastases seven years after total thyroidectomy and neck dissection followed by radioactive iodine ablation (RAI) for FV-PTC. Metastasectomy was performed by pancreaticoduodenectomy followed by sorafenib as genetic testing revealed a BRAF V600E mutation. She survived 32 months after the pancreatic metastasis diagnosis. Conclusion. Pancreatic metastases are rare manifestation of FV-PTC and are usually sign of extensive disease and conventional diagnostic tools may remain to reach the diagnosis.

10.
Case Rep Urol ; 2013: 651081, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23662243

RESUMO

Background. Renal cell carcinoma (RCC) has unpredictable and diverse behavior. The classic triad of hematuria, loin pain, and abdominal mass is uncommon. At time of diagnosis, 25%-30% of patients are found to have metastases. Bones, lungs, liver, and brain are the frequent sites of metastases. RCC with metastasis to the head and neck region and thyroid gland is the rarest manifestation and anaplastic carcinoma behaving metastatic thyroid mass is an extremely rare presentation of RCC. Case Presentation. A 56-year-old Saudi man with past history of right radical nephrectomy 5 years back presented with 3 months history of rapid increasing neck mass with dysphagia, presenting like anaplastic thyroid carcinoma. Tru-cut biopsy turned out to be metastatic renal cell carcinoma. Patient was treated with radiation therapy 30 Gy in 10 fractions to mass. Patient died 4 months after the discovery of anaplastic thyroid looking metastasis. Conclusion. Rapidly progressing thyroid metastases secondary to RCC are rare and found often unresectable which are not amenable to surgery. Palliative radiotherapy can be considered for such patients.

11.
Case Rep Endocrinol ; 2013: 192573, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23607000

RESUMO

Introduction. Follicular thyroid carcinoma (FTC) frequently metastasizes to the lungs and bones. However, metastasis to the skeletal muscles is an extremely rare manifestation of FTC. To date, only seven cases of FTC have been reported in the literature. Skeletal muscle metastases from FTC usually remain asymptomatic or manifest as swelling and are associated with dismal prognosis. Case Presentation. A 45-year-old Saudi woman presented with right buttock swelling since 8 months. Physical examination revealed right gluteal mass of size 13 × 10 cm and right thyroid lobe nodule. The rest of examination was unremarkable. Magnetic resonance imaging (MRI) showed 13 × 11.7 × 6.8 cm lobulated mass arising from the gluteus medius muscle, and tru-cut biopsy confirmed the metastatic papillary carcinoma of thyroid origin. The patient subsequently underwent palliative radiotherapy followed by total thyroidectomy and radioactive iodine ablation. At the time of publication, the patient was alive with partial response in gluteal mass. Conclusion. Skeletal muscles metastases are a rare manifestation of FTC, and searching for the primary focus in a patient with skeletal muscle metastasis, thyroid cancer should be considered as differential diagnosis.

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