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1.
J Microsc ; 291(3): 210-228, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37357432

RESUMO

Nanocrystalline Ti1- x Crx O2 (0 ≤ x ≤ 0.20) samples were synthesised via acid-modified sol-gel process and characterised with various techniques, such as HRTEM, FESEM, Raman, XPS, DTA and VSM. The TEM image of TiO2 exhibits elongated nanoparticles with an average size of 10 nm. The HRTEM in combination with selected area electron diffraction (SAED) reveals the interplanar spacing and polycrystalline nature of the samples, respectively. FESEM micrographs divulge nonuniform morphologies and less aggregation of the particles in the doped sample. Raman spectra ensure the phase purity of the samples and a blue shift on Cr doping. X-ray photoelectron spectra (XPS) predict the chemical state of the elements and oxygen vacancies in the prepared samples. Room temperature magnetic measurements exhibit a significant variation in the magnetic parameters on Cr doping in TiO2 . The differential thermal analysis (DTA) shows the structural phase transition at ∼630°C. The photocatalytic performance is studied for the degradation of methylene blue (MB) dye under visible light irradiation. A higher photocatalytic efficiency is found for the 20% of Cr-doped TiO2 . These studies propose that the appropriate incorporation of Cr ions makes TiO2 very efficient for visible light-driven photocatalysts required for applications in wastewater treatment. LAY DESCRIPTION: In the present study, nanoparticles of TiO2 and Cr-doped TiO2 have been synthesised by a cost-effective acid-modified sol-gel process. The effect of Cr doping on the microstructure, thermal, magnetic and photocatalytic properties of TiO2 were explored in detail. The transmission electron microscopy (TEM) images exhibit the presence of elongated nanoparticles with an average size of 10 nm. Field emission scanning electron microscopy (FESEM) was used to study the surface morphology of the synthesised materials, which revealed nonuniform morphologies and less aggregation of the particles in the Cr-doped sample. Energy dispersive x-ray spectroscopy (EDS) confirms the elemental compositions with the appropriate stoichiometry of the elements. Raman spectra ensure the phase purity of the materials and also a blue shift with the incorporation of Cr ions in TiO2 . X-ray photoelectron spectra (XPS) predict the chemical state of the elements and oxygen vacancies in the prepared samples. The magnetic nature of all the synthesised samples was examined through the vibrating sample magnetometer (VSM) and revealed weak ferromagnetic behaviour of the samples. These results signify that the oxygen vacancies and defects play a crucial role in developing the ferromagnetic nature of oxide semiconductors. The differential thermal analysis (DTA) shows the structural phase transition at ∼630°C. The photocatalytic performance of the prepared samples was studied for the degradation of methylene blue (MB) dye under irradiation of visible light. A higher photocatalytic efficiency was found for the 20% of Cr-doped TiO2 . These studies propose that the appropriate incorporation of Cr ions makes TiO2 very efficient for visible light-driven photocatalysts required for applications in wastewater treatment.

2.
Ann Med Surg (Lond) ; 77: 103603, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35638013

RESUMO

Introduction: Acute appendicitis is one of the leading causes of acute abdominal pain and surgical emergency. Stump appendicitis is a known complication of appendectomy whereby a retained appendiceal tip serves as a nidus for recurrent bouts of inflammation. Nevertheless, full-blown appendicitis of the vermiform appendix after a prior appendectomy remains a diagnostic conundrum. Case presentation: A 45-year-old woman presented with a six-month history of right iliac fossa pain. Pertinently, she had undergone a prior open appendectomy twelve years ago. Further investigative workup revealed full-blown appendicitis, which was not attributable to a retained appendiceal stump. A subsequent laparoscopic appendectomy was performed, and the resultant specimen was sent for further evaluation, confirming the diagnosis of recurrent appendicitis. Clinical discussion: Acute appendicitis is one of the most common life-threatening abdominal surgical emergencies worldwide, with 300000 appendectomies performed annually in the United States alone. Stump and chronic appendicitis are two separate and exceedingly rare clinical entities that may present simultaneously and develop serious complications unless promptly recognized and appropriately managed. The present paper prompts the clinicians to distinguish amongst the two at the initial surgery in order to thwart further exacerbations. Conclusion: While stump appendicitis is a rare but well-characterized complication of a prior appendectomy, full-blown appendicitis of vermiform appendix remains elusive. It is therefore imperative to distinguish between a duplicated and a recurrent appendix at the initial operative procedure to facilitate optimal patient management.

3.
Ann Med Surg (Lond) ; 77: 103648, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35638027

RESUMO

Introduction: Pancreatic pseudocysts remain a feared complication of acute or chronic pancreatitis and are often characterized by collections of fluids due to underlying damage to the pancreatic ducts, culminating in a walled-off region bereft of an epithelial layer but surrounded by granulation tissue. While fungal infections of pancreatic pseudocysts are rarely encountered, candida albicans remains the most frequently implicated organism. Case presentation: A 55-year-old male presented with pain in the left-hypochondriac region, accompanied by non-bilious emesis and nausea. Interestingly, the patient also tested positive for a COVID-19 infection. Investigative workup divulged enhancing pancreatic walls with a radiologic impression consistent with a pancreatic pseudocyst. An ultrasound-guided external drainage was performed; the drainage was conducted unremarkably, with the resultant fluid collection revealing the presence of Candida Glabrata. The patient was commenced on antifungal therapy and continues to do well to date. Discussion: Infectious ailments of pancreatic pseudocysts remain a widely known complication of acute pancreatitis. While it is rare, fungal infection is a crucial consideration for patients with pancreatic pseudocysts, especially in the context of a lack of an adequate response to antibiotics, deterioration, comorbidities, and immunocompromised states. Conclusion: Rapid identification of the microbe responsible for pancreatic pseudocyst infection is vital for time-sensitive treatment and a more rapid recovery, curbing associated morbidity and mortality.

4.
Sci Rep ; 12(1): 3962, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35273263

RESUMO

In this study, novel growth of WO3-ZnSe nanocomposites was carried out by a simple, low-cost hydrothermal process under subcritical conditions and is reported for the first time in just 5 h. The products were characterized in detail by multiform techniques: X-ray diffraction, scanning electron microscopy (SEM), optical studies, and Fourier transform analysis. The influence of ZnSe on the structural, morphological, compositional, optical, and catalytic properties of WO3 is demonstrated. The WO3 metal oxide material is grown in a hexagonal crystal structure with wide-band-gap and has been modified by ZnSe to form a composite nanostructures in the nanoscale range. The electrochemical properties of the prepared materials were studied by cyclic voltammetry, which revealed that the synthesized material exhibited remarkable electrochemical supercapacitive activity. Moreover, the composite nanostructures showed excellent photocatalytic activity for degradation of phenol and almost 93% of phenol was degraded with good recyclability and stability. According to The International Commission on Illumination (CIE), the synthesized nanomaterial shows blue emission and is suitable for blue LEDs.

5.
Talanta ; 241: 123257, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35114490

RESUMO

Development of multifunctional ternary nanocomposite based electrocatalysts for detection of toxic elements and generation of renewable energy describes an environmentally sustainable technique to address the dual challenges of pollution and energy. Herein, we adopted microwave-assisted synthesis to design a multifunctional graphitic carbon nitride (g-C3N4) decorated BiVO4/Ag2CO3 (BVG@C) hierarchical ternary nanocomposite for sensing and water splitting applications. The morphological, structural and elemental characterizations demonstrate the successful decoration of carbon nitride on the composite surface. The electrochemical activity of BVG@C modified glassy carbon electrode reveals excellent redox behaviour towards simultaneous detection of 4-Nitrophenol (4-NP) and 4-Nitroaniline (PNA). The modified electrode shows rapid amperometric current response with high sensitivity of 2.368 µA mM cm-2 and 1.534 mA mM cm-2 and low detection limit of 0.012 µmol L-1and 0.028 µmol L-1, respectively for 4-NP and PNA. Moreover, the modified electrode was further investigated for hydrogen evolution and oxygen evolution reactions and the electrocatalytic results show admirable activity and good stability for oxygen evolution with very low overpotential of 136 mV in alkaline medium. It is worthwhile to mention that the excellent activity of electrocatalyst can be ascribed to the decoration and electronic interaction of g-C3N4 with the BiVO4/Ag2CO3 nanocomposite, increasing its surface area, active sites, charge transfer and decreasing resistance.


Assuntos
Nanocompostos , Água , Carbono , Técnicas Eletroquímicas/métodos , Eletrodos , Nanocompostos/química
6.
Ann Med Surg (Lond) ; 71: 103016, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34840764

RESUMO

Left-sided gallbladder (LSGB) is a rare anatomic variation that, while benign in the context of its transposition, is of significant intraoperative importance. Due to its association with other anatomic anomalies involving key structures in the hepatobiliary system, discovering it intraoperatively as opposed to preoperatively suddenly increases the difficulty of a gallbladder procedure.

7.
ANZ J Surg ; 91(10): 2097-2105, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33890719

RESUMO

AIM: To develop a model of clinical factors that may predict: (1) technically and clinically successful embolization of a bleeding vessel at digital subtraction angiography (DSA) for lower gastrointestinal bleed (LGIB); (2) a negative DSA in the presence of positive CT-mesenteric angiography (CTMA) for LGIB. METHODS: A retrospective cohort study of all DSAs conducted with intent for embolization for acute LGIB over a 10-year period was undertaken. Pre-procedural and intra-procedural clinical variables were evaluated using uni- and multi-variate analysis. RESULTS: One hundred and twenty-three DSAs were evaluated. Technical success was 81% and clinical success 78% where DSA was positive. Technical success was associated with super-selective approach, contrast extravasation on CT, haemoglobin drop, anatomical source and time from CT to DSA on univariate analysis. On multivariate analysis, time from CT to DSA was significant with a higher success probability within 120 min with different factors being salient depending on degree of delay. Clinical success was only associated with activated partial thromboplastin time (<27.5 s). A negative DSA was associated with anatomical source, haemodynamic stability, platelet count and time from CT to DSA on univariate analysis. The latter three remained so on multivariate analysis. CONCLUSION: A triaging approach to utilizing emergency DSA may be helpful. If prolonged delay between CT and DSA is anticipated, with haemodynamic stability and a near-normal platelet count, the DSA may not be fruitful. Technical success may be more likely if DSA occurs within 120 min. Clinical success may be more likely if activated partial thromboplastin time is within normal range.


Assuntos
Embolização Terapêutica , Hemorragia Gastrointestinal , Angiografia Digital , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/terapia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
8.
Cureus ; 12(8): e9913, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32968575

RESUMO

Introduction Soft tissue sarcomas remain an exceedingly rare malignancy. While soft tissue sarcomas boast a high mortality rate, their characteristics and behavior patterns are poorly understood. This study aims to evaluate the various aspects that pertain to soft tissue sarcomas, including their histology, tumor characteristics, survival rates, and therapeutic modalities. Methods A retrospective study analyzing the data from 19 patients presenting over four years with a histologically confirmed diagnosis of soft tissue sarcomas was conducted. The patients were studied for various parameters, including tumor site and the particular pathological subtypes. The data obtained were analyzed using the SPSS 23.0 statistical software (IBM Corporation, Armonk, NY), and the results were then tabulated. Results A total of 19 patients with a confirmed diagnosis of a soft tissue sarcoma were included in the study. The mean age of the patients included was 45.32 ± 16.88 years. Wide local excision was the most common surgical procedure employed for the resection of these tumors. Within the cohort, the mortality rate was noted to hover at 10.52%. Gastrointestinal stromal tumors were observed in 21% of the patients and were therefore the most common histological subtype. Of the patients included, 42.10% required blood transfusion during the perioperative time. Most of the tumors were noted to be intermediate grade, with high-grade tumors observed in 26.3% of the cases. Conclusion Soft tissue sarcomas remain a rare but potent cause of death in developing countries. The diversity of the tissues that they afflict renders their prompt detection a diagnostic challenge. A meticulous exploration of the various characteristics honed by soft tissue sarcomas, such as the particular histological subtype and the associated mortality rates, can better elucidate the prognosis and the eventual disease outcomes.

9.
Cureus ; 12(8): e9941, 2020 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-32968601

RESUMO

Background Breast cancer remains the most common cause of cancer related mortality amongst women in Pakistan. Postoperative complications can demoralize the patients and potentially delay adjuvant treatment, leading to adverse outcomes. The overarching aim of the study is to delineate the early postoperative outcomes of breast cancer surgery in Pakistan. Materials and Methods A retrospective study involving patients who underwent breast cancer surgery from June 2016 to December 2019 was conducted. Perioperative morbidities (30 days) were evaluated and documented. The results obtained were analyzed using the SPSS 23 software (IBM Corporation, Armonk, NY). Results A total of 94 patients were included in the study, with the mean age of 50±12.8 years. Breast conserving surgery was performed in 32% (n=31) of the patients, while the remaining 68% (n=63) underwent modified radical mastectomy. The most common complications were seroma formation, flap necrosis and hematoma formation and were observed in 5.3% (n=5), 4.3% (n=4) and 3.2% (n=3) of the patients, respectively. Conclusion Early postoperative complications can delay the commencement of adjuvant systemic therapy required for further management of breast cancer. These complications elicit equally grave consequences for patients undergoing breast conserving surgery and modified radical mastectomy.

10.
ACS Omega ; 4(7): 12905-12918, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31460417

RESUMO

Visible light-driven Ag2S-grafted NiO-ZnO ternary nanocomposites are synthesized using a facile and cost-effective homogeneous precipitation method. The structural, morphological, and optical properties were extensively studied, confirming the formation of ternary nanocomposites. The surface area of the synthesized nanocomposites was calculated by electrochemical double-layer capacitance (C dl). Ternary Ag2S/NiO-ZnO nanocomposites showed excellent visible light photocatalytic property which increases further with the concentration of Ag2S. The maximum photocatalytic activity was shown by 8% Ag2S/NiO-ZnO with a RhB degradation efficiency of 95%. Hydroxyl and superoxide radicals were found to be dominant species for photodegradation of RhB, confirmed by scavenging experiments. It is noteworthy that the recycling experiments demonstrated high stability and recyclable nature of the photocatalyst. Moreover, the electrochemical results indicated that the prepared nanocomposite exhibits remarkable activity toward detection of acetone. The fabricated nanocomposite sensor showed high sensitivity (4.0764 µA mmol L-1 cm-2) and a lower detection limit (0.06 mmol L-1) for the detection of acetone. The enhanced photocatalytic and the sensing property of Ag2S/NiO-ZnO can be attributed to the synergistic effects of strong visible light absorption, excellent charge separation, and remarkable surface properties.

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