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B J Boyd

Publications and source records attributed to B J Boyd.

5 recordsLinked to original sources
PubMed2006

Characterisation of bicontinuous cubic liquid crystalline systems of phytantriol and water using cryo field emission scanning electron microscopy (cryo FESEM).

Cubosomes are a novel lipid particulate delivery system currently being investigated for drug delivery purposes. The present study investigates bicontinuous cubic liquid crystalline systems (bulk phase and cubosomes) formed by phytantriol and water using cryo field emission scanning electron microscopy (cryo FESEM). Previously cubosomes have been characterized by cryo transmission electron microscopy (cryo TEM) with small angle X-ray diffraction (SAXS) confirming the bicontinuous liquid crystalline type. Bulk cubic phase and cubosomes were prepared from phytantriol and Pluronic F127 and analysed using cryo FESEM and SAXS. The micrographs showed the cubic phase had a tortuous, bicontinuous nature with a non-intersecting network of water channels. The cubosomes also show the same underlying tortuous structure entirely consistent with that of the bulk cubic phase and closely resemble the mathematical description of cubosomes described using nodal surface representation. The structure of both systems was confirmed using SAXS as a bicontinuous cubic liquid crystalline phase with Pn3m geometry. Cryo FESEM provides valuable insights into the morphological features of bicontinuous cubic liquid crystalline systems. The unique details shown provide strength to support the nodal surface representation of bicontinuous cubic liquid crystalline systems. Cryo FESEM provides a new technique to complement cryo TEM and SAXS for investigating their structure and function.

Cryoelectron Microscopy↗
PubMed1999

The free iliac crest and fibula flaps in vascularized oromandibular reconstruction: comparison and long-term evaluation.

BACKGROUND: A variety of free flaps have been successfully used for mandible reconstruction. This study compared the short- and long-term results of using the free iliac crest and fibula flaps. METHODS: We conducted a retrospective analysis of 117 patients who underwent mandibular reconstruction, 59 patients with iliac crest and 58 with free fibula. Accurate long-term functional assessment was possible in 31 cases in the iliac crest group and in 48 patients with fibular reconstruction. Anterior or combined anterolateral defects formed 72% and 64% in the iliac crest and fibula groups, respectively. The remainder were pure lateral defects. In both series, a skin paddle was included to provide either lining, skin cover, or both in 77% of the cases, whereas in 23% bone only was used. RESULTS: Complications included two perioperative deaths and three flap losses in the iliac crest group and five flap losses in the fibula group. Long-term functional and cosmetic assessment showed no statistically significant differences in oral continence (p > 0.9), speech (p = 0.57), and contour results (p = 0.80) between the two groups. However, oral deglutition was statistically significantly better in the fibula free flap group (p = 0.009). CONCLUSION: Although the fibula free flap is the flap of choice, the iliac crest is an excellent and reliable complementary flap for mandibular reconstruction.

Adult↗
PubMed1997

Oromandibular reconstruction with the fibular free flap. Analysis of 50 consecutive flaps.

OBJECTIVE: To evaluate the results and functional outcome associated with fibular free flap reconstruction of orofacial and mandibular defects. DESIGN: We conducted a retrospective analysis of 50 consecutive fibular free flaps during a 3-year period. Forty patients were available for follow-up, which ranged from 4 to 39 months. SETTING: Academic tertiary care referral medical center. PATIENTS: Fifty consecutive mandibular reconstructions using the fibular free flap were performed on 47 patients. Thirty-five patients (74%) underwent primary reconstruction. Sixty-six percent of the mandibular defects were anterior or combined anterolateral types; the remainder were pure lateral defects. In 38 patients (81%), a skin paddle was included with the flap to provide either a mucosal lining or skin cover, whereas in only 9 patients (19%), bone was used alone. MAIN OUTCOME MEASURES: Factors reflecting functional properties and processes as well as complications of the upper aerodigestive tract were evaluated clinically and radiographically. RESULTS: Four flaps required reexploration as emergencies, and none were successfully salvaged (8.5% failure). Three patients underwent further free vascularized fibula transfer with 1 failure. During follow-up, swallowing was normal in 25 patients (64%), oral continence was normal or almost normal in 26 patients (67%), and speech was normal or easily intelligible in 35 patients (90%). Aesthetic results were excellent or acceptable in 37 patients (95%). CONCLUSIONS: Our results reveal that the vascularized fibular free flap is very suitable with an excellent success rate for reconstructing both the composite or simple long-spanned mandibular defect. The overlying skin island is reliable and provides lining or coverage for intraoral and extraoral defects. Superior functional cosmetic results are expected in the majority of patients, while donor site morbidity is minimal.

Adult↗