Hemp globulin forms colloidal nanocomplexes with sodium caseinate during pH-cycling.

Seed from industrial hemp (Cannabis sativa L.) contains around 25% protein (mainly globulins) which is easily digested, but the low solubility of hemp globulins (HG) limits their application in many food systems. In this study, the solubility of HG was improved by blending HG with sodium caseinate (SC) and treating with a pH-cycling process. The pH-cycling involved adjusting the pH to 12 and reacting for 1 hr, followed by neutralisation to pH 7. Nanoparticles composed of HG and SC (Z-average diameter ≈ 130 nm) were formed after the pH-cycling, and the solubility of HG increased to > 80% when there was more than 1% of SC for 1% of HG. These HG|SC nanoparticles were monodisperse (PDI < 0.17) and ζ-potential was ≈ -17 mV. Hydrogen bonding is the main forces that assembles HG|SC nanoparticles because the nanoparticles dissociated by heat treatment (up to 60 °C) or urea, which is an effective hydrogen bond breaker. HG|SC nanoparticles will aggregate irreversibly above 60 °C, possibly due to thiol-disulphide exchange. The nanoparticles were heat-stable as the Z-average diameter was only 229 nm after heating (90 °C, 30 min). N-ethylmaleimide blocked free thiol groups on HG and resulted in less disulphide-linked HG aggregation after pH- cycling, which in turn lead to smaller HG|SC nanoparticles and a bimodal particle size distribution, indicating the importance of disulphide bond for the formation of monodisperse HG|SC nanoparticles. The soluble and heat-stable HG|SC nanoparticles could be used to increase the hemp protein content in beverages and emulsions.

Concentrated Pickering emulsions stabilised by hemp globulin-caseinate nanoparticles: tuning the rheological properties by adjusting the hemp globulin : caseinate ratio.

Industrial hemp (Cannabis sativa L.) is an underutilised novel protein source. However, the utilisation of hemp seed protein is limited by its low solubility in water. Soluble nanoparticles were made by complexing hemp globulin (HG) with sodium caseinate (SC) via a pH-cycling method. Oil-in-water Pickering emulsions were made with these co-assembled protein nanoparticles. The emulsions were composed of 70% oil phase and 30% water phase (v/v), and contained 2% protein (w/v, pure SC or HG-SC nanoparticles with an HG : SC ratio of 1 : 2 or 1 : 1). All emulsions were stable during 21 days of storage, as there was no phase separation, coalescence or flocculation. At day 0, all emulsions were solid-like (G' > G'') regardless of the protein composition. The rheological properties of the emulsions during storage could be tuned by controlling the HG : SC ratio in the HG-SC nanoparticles, i.e. the emulsions became more solid-like over time when there was more HG in the nanoparticles. In contrast, emulsions stabilised by pure SC became more liquid-like during storage. The internal structure and interactions within the emulsions were evaluated by fitting frequency sweep test data according to a co-operative theory of flow. The result suggested that the solid-like emulsion resulted from stronger short-range interactions between flocs of oil droplets, which developed during storage when there was more HG in the HG-SC nanoparticles, and not from the formation of a three-dimensional network. These HG-SC nanoparticles can be used to control the rheological properties of an emulsion during its shelf life.

Computer-aided auscultation learning system for nursing technique instruction.

Pulmonary auscultation is a physical assessment skill learned by nursing students for examining the respiratory system. Generally, a sound simulator equipped mannequin is used to group teach auscultation techniques via classroom demonstration. However, nursing students cannot readily duplicate this learning environment for self-study. The advancement of electronic and digital signal processing technologies facilitates simulating this learning environment. This study aims to develop a computer-aided auscultation learning system for assisting teachers and nursing students in auscultation teaching and learning. This system provides teachers with signal recording and processing of lung sounds and immediate playback of lung sounds for students. A graphical user interface allows teachers to control the measuring device, draw lung sound waveforms, highlight lung sound segments of interest, and include descriptive text. Effects on learning lung sound auscultation were evaluated for verifying the feasibility of the system. Fifteen nursing students voluntarily participated in the repeated experiment. The results of a paired t test showed that auscultative abilities of the students were significantly improved by using the computer-aided auscultation learning system.

Inflammatory pseudotumor of the sinonasal tract.

Inflammatory pseudotumors (IPTs) are a clinically and histologically diverse group of lesions characterized by a tumor mass of acute and chronic inflammatory cells with a variable fibrous response. IPTs most commonly involve the lung and orbit, but rarely the sinonasal tract. We report a 68-year-old male with an IPT of the sinonasal tract presenting as nasal obstruction and postnasal dripping for several years. A gray-white soft mass was noted in the right nasal cavity. Computed tomography revealed a solid mass filling the right nasal cavity and maxillary sinus. Caldwell-Luc operation with ethmoidectomy (right) was conducted to resect the mass en bloc. Pathology revealed admixture of plasma cells, lymphocytes and eosinophils, confirming the diagnosis of IPT. The patient remained symptom-free over 4 years of follow-up. Awareness of the clinical presentations, histopathologic features and treatment of choice of this rare disease entity is necessary to distinguish it from malignancy and avoid unnecessary management.

Submandibular cavernous hemangiomas with multiple phleboliths masquerading as sialolithiasis.

Vasoformative tumors (almost exclusively hemangiomas) are the most common lesions of the major salivary glands during infancy and early childhood. They are more common in the parotid gland but are particularly rare in the submandibular gland. Changes in blood flow dynamics within hemangiomas result in thrombus formation and phleboliths. Hemangiomas of the salivary glands in adults are histologically unlike those in infants, the former being characteristically of the cavernous variant. Most cavernous hemangiomas require surgery since they do not show a tendency to regress. A case of an adult man with cavernous hemangioma affecting the submandibular salivary gland that clinically simulated sialolithiasis is presented to alert surgeons to the possibility of such a lesion. We describe the clinical course and review the literature.

Pilomatrixoma of the head and neck.

Pilomatrixoma is a benign skin appendage tumor that commonly occurs as a solitary lesion and is not usually hereditary. There is evidence to suggest that patients with a family history of multiple pilomatrixomas have a high probability of autosomal dominant disorders such as myotonic dystrophy, Gardner syndrome, and Rubinstein-Taybi syndrome. In January 2004, a case was reported of an 8-year-old girl with 2 progressively enlarged facial masses. One of them was excised and diagnosed as pilomatrixoma. Coincidently, her 13-year-old sister had the same type of tumor when she was 4 years old. We report this unusual case and review the literature. Pilomatrixoma has not been widely reported in the head and neck surgery literature. This benign tumor may be misdiagnosed as a carcinoma, resulting in unnecessary aggressive therapy. Otolaryngologists should therefore note the clinical and pathologic characteristics of these symptoms.

Madelung's disease.

Madelung's disease is a rare disease of undetermined cause characterized by symmetric deposits of painless, diffuse, subcutaneous adipose tissue on the suboccipital area, the cheeks, the neck, the shoulders and the upper trunk. It is commonest in countries bordering the Mediterranean. The patients are usually middle-aged male alcoholics. Although lesions can initially mimic a head and neck malignancy, management is essentially symptomatic, with conservative removals done as indicated clinically or for cosmesis. Oriental reports about Madelung's disease are very rare. Here a case of Madelung's disease in a 59-year-old male is described. We describe his clinical course and review the literature.