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Porosity asymmetric membrane capsules were prepared to study the relationship between the capsule formulation and drug release. Cellulose acetate (CA) and pore formers were used in the capsule shell formulation as the main semipermeable membrane material. The capsules were permeable to both water and dissolved solutes. Using sparingly soluble drug acetaminophen as a model, cumulative release was calculated. The slope of the release profile from the distilled water had good relationship with the concentration of the pore formers F68. The release of acetaminophen was independent to the pH, osmotic pressure of dissolution medium, but influenced by intensity of agitation. When the concentration of pore former was low, zero-order release behavior was observed within 24 h which was consistent with Fickian diffusion model. When the concentration of pore former was high, however, Higuchi model release was found which is caused by Fickian diffusion and osmotic pressure release. With scanning electron microscope (SEM), the surface structure and cross-section of the capsule shell were also studied before and after drug delivery. With simple preparation and broad scope of drug application, porosity asymmetric membrane capsules can give desired drug extended release and show more convenience than controlled tablets with laser drilling.

As the ageing population continues to increase, the prevalence of age-related cognitive impairment has been on the rise. Mild cognitive impairment (MCI) is now widely recognised as the early stage of dementia. Mild cognitive impairment is closely associated with cerebral white matter lesions (WMLs), specifically in the case of leukoaraiosis (LA). A previous diffusion tensor imaging (DTI) has demonstrated that white matter changes might damage cognitive function in LA patients, and the cognitive function might decrease with the deterioration of LA. Through consulting and analysing documents, we found that both of them share similarities in risk factors, pathogenesis, pathological changes, and imaging manifestations. The main characteristics of LA patients with MCI (LACI) are the early and apparent manifestations of delayed memory, attention, impaired executive function, and close association with dementia. This analysis of LACI may contribute to an early diagnosis of LACI and provide possible treatment for LACI.

To explore the operative technique and clinical results of using peroneal perforator-based sural neurofasciocutaneous flaps to repair skin and soft tissue defects in lower extremities.From January 2009 to March 2012, 26 patients with skin and soft tissue defects at distal region of leg and foot were hospitalized. Among them, 9 patients suffered from tendon or bone exposure at the distal region of leg after injury due to traffic accident; 4 patients suffered from skin defects in the ankle as a result of electric injury; 8 patients suffered from chronic ulcer at the distal part of leg and foot; 5 patients suffered from plantar pressure ulcer. After debridement, soft tissue defect sizes ranged from 11 cm×5 cm to 18 cm×13 cm. According to the position and size of the defects, peroneal perforator-based sural neurofasciocutaneous flaps were designed and procured to repair the skin and soft tissue defects. The size of flaps ranged from 12 cm×6 cm to 20 cm×15 cm. Flap donor sites were closed by direct suture or skin grafting.Twenty-five flaps survived completely. Only one flap suffered partial margin necrosis in the size of 2 cm×1 cm, which was healed after dressing change. Patients were followed up for 6 to 12 months. The appearance and sensation of flaps were satisfactory; no ulcer occurred; the movement of lower extremities was normal.It is suitable to repair the skin and soft tissue defects at distal region of leg and foot with the peroneal perforator-based sural neurofasciocutaneous flap, as it possesses reliable blood supply, long and non-bulky pedicle, and sufficient available size. The operation is also easy to perform.