Microwave-Aided Exfoliation and Reduction of Graphene Oxide.

Wet chemical oxidation methods have been widely used to prepare graphene oxide from graphite flakes, which in turn can be reduced using strong and hazardous chemicals like hydrazine. In this report, we have demonstrated a non-hazardous method for simultaneous exfoliation and reduction of graphene oxide. Fourier transformed infrared (FTIR), UV-Visible, X-ray diffraction and Raman spectroscopic techniques have been used to ascertain chemical functionalization and reduction of graphene oxide. Morphological studies were carried out using field emission scanning electron microscopy. Morphological details of the microwave reduced graphene showed enhancement in inter-layer spacing of graphene sheets after microwave treatment. The enhancement in electrical conductivity of graphene oxide after microwave treatment indicates its efficient reduction.

Understanding primary parotid squamous cell carcinoma - A systematic review.

INTRODUCTION: The true incidence of primary parotid squamous cell carcinoma (SCC) is unknown and likely overestimated in the literature. The aim of this systematic review is to examine the diagnosis, aetiology and incidence of parotid SCC by analysing studies evaluating primary parotid SCC. METHODS: A systematic search of Medline, EMBASE and Cochrane library was performed. A narrative synthesis was done. RESULTS: A total of 14 observational retrospective studies on primary parotid SCC were included. There are currently no standard criteria for ascertainment of primary parotid SCC. Primary parotid SCC is thought to be due to squamous metaplasia within the ductal epithelium and subsequent invasive squamous carcinoma. Histological features that favour primary disease includes SCC confined to parotid parenchyma with no direct communication to the skin and the absence of mucin. Incidence of primary parotid SCC varied from 1.54 to 2.8 cases per million person-years. Around 30%-86% of patients recorded to have primary parotid SCC on clinical records, when scrutinised, were in fact secondary to parotid lymph node involvement following regional advancement from skin or upper aerodigestive tract SCC. CONCLUSION: Primary parotid SCC is rare and it is currently a diagnosis of exclusion. Thorough clinical assessment including endoscopy, preoperative imaging and the scrutiny of histopathological findings allow for differentiation between primary and secondary SCC within the parotid. This thus affects both initial treatment and subsequent follow-up.

Radiofrequency ablation in the treatment of paediatric microcystic lymphatic malformations.

OBJECTIVE: Congenital lymphatic malformations are a challenging clinical problem. There is currently no universally accepted treatment for the management of microcystic disease. We describe the novel use of an existing technology (radiofrequency ablation, also termed Coblation) for the debulking of paediatric microcystic lymphatic malformations involving the upper aerodigestive tract. METHODS: Five children with microcystic or mixed-type lymphatic malformations were included in this retrospective case series. RESULTS: Each child had a satisfactory outcome following radiofrequency debulking, with improved oral intake and airway symptoms. No serious complications were reported. These findings constitute level IV evidence. CONCLUSION: We recommend radiofrequency ablation as a safe, viable alternative to existing techniques for the treatment of paediatric microcystic lymphatic malformations of the upper aerodigestive tract. Radiofrequency ablation achieves effective debulking of microcysts whilst avoiding excessive bleeding and thermal damage to surrounding tissues. This paper constitutes the first report of successful treatment of airway obstruction due to paediatric laryngopharyngeal microcystic disease, using radiofrequency ablation.

Failure of propranolol in the treatment of childhood haemangiomas of the head and neck.

BACKGROUND: Infantile haemangiomas enter a rapid proliferative phase within months of birth, before slowly involuting. Those with the potential for disfigurement or morbidity require intervention. Propranolol has emerged as an effective new treatment modality, with the potential to become the first-line treatment of choice. METHODS: Four children with haemangiomas of the head and neck were treated with propranolol at a tertiary referral centre. The size of the haemangioma and the symptoms resulting from airway compromise were monitored. RESULTS: Three of the four children showed a dramatic response to treatment with propranolol. However, one child responded initially but was readmitted with stridor secondary to new haemangioma proliferation. CONCLUSIONS: We report a cautionary case in which a subglottic haemangioma developed contemporaneously with propranolol treatment, requiring surgical intervention. This finding highlights the need for regular follow up of treatment response, and the need for monitoring for treatment side effects.

Bronchogenic cysts as a cause of infantile stridor: case report and literature review.

INTRODUCTION: Cystic lesions related to the upper airway are an unusual cause of infantile stridor. Such a lesion may exert a mass effect, with subsequent airway compromise. CASE REPORT: A six-month-old boy was transferred to our unit with a right-sided, level IV neck lump and a three-month history of chronic cough and, latterly, inspiratory stridor. Computed tomography revealed a large, unilocular, cystic, cervicothoracic lesion causing marked compression of the trachea. Airway endoscopy subsequently revealed the larynx to be displaced to the left, with severe external compression of the trachea from just below the subglottic level to immediately above the carina. The mediastinal lesion was excised via an external approach. The histological diagnosis was a bronchogenic cyst. CONCLUSION: Bronchogenic cysts are a rare cause of infantile stridor, and should be considered in the differential diagnosis of cystic cervical and mediastinal masses. Surgical excision is the treatment of choice.

Overexpression of aldehyde dehydrogenase 1A1 reduces oxidation-induced toxicity in SH-SY5Y neuroblastoma cells.

Oxidative stress leading to lipid peroxidation is a problem in neurodegenerative diseases, because the brain is rich in polyunsaturated fatty acids and low in endogenous antioxidants. One of the most toxic byproducts of lipid peroxidation, 4-hydroxynonenal (HNE), is implicated in oxidative stress-induced damage in neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). In this study, the human neuroblastoma cell line SH-SY5Y was used to test the protective effects of increasing the detoxification of HNE by overexpressing the HNE-detoxifying enzyme aldehyde dehydrogenase 1A1 (ALDH1). Overexpression of ALDH1 in the SH-SY5Y cells acts to reduce production of protein-HNE adducts and activation of caspase-3. Our data suggest that detoxification of HNE could be therapeutic in preventing some of the toxic disruptions of the brain's redox systems found in many neurodegenerative diseases.