The pursuit of bright smile : tooth whitening among Hong Kong young adults

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A metaphyseal fracture rat model for mechanistic studies of osteoporotic bone healing

Most osteoporotic fractures occur at metaphyseal regions of long bones. The present study proposed a clinically relevant animal model that satisfied: i) induction of osteoporosis, ii) unilateral complete osteotomy at metaphysis, iii) internal fixation. 6 months old female Sprague-Dawley rats (n = 64) were randomly divided into the ovariectomised-metaphyseal osteotomy (OVX, n = 32) and metaphyseal osteotomy (SHAM, n = 32) groups. The metaphyseal-osteotomy model was created with a plate-fixation of the osteotomy and assessed by X-ray, micro-computed tomography, histomorphometry and mechanical testing at weeks 1, 3 and 6. X-ray results showed complete healing of metaphyseal osteotomy at week 6. Histology showed 3 stages of metaphyseal healing. Stage 1 was characterised by fibrous tissue, consisting of disorganised orientation of collagen fibres, and infiltration of immune cells. At stage 2, a transitional zone consisting of maturing fibrous tissue and differentiating mesenchymal cells with early trabecular bone formation and disorganised woven bone were observed. During stage 3, cortical bone ends unified and woven bone underwent transformation to lamellar bone. OVX group healing was significantly delayed when compared to SHAM samples. The study demonstrated that healing of osteoporotic osteotomy at the metaphyseal region was delayed in terms of radiography, histomorphometry and mechanical strength. These quantitative evaluations, along with histological features, may provide key references for future studies. The animal model may provide additional clinical relevance as most osteoporotic fracture in humans occurs at metaphyseal regions

Use of the International Prostate Symptom Score (IPSS) in Chinese male patients with benign prostatic hyperplasia

Purpose: To test the psychometric properties of the International Prostate Symptom Score (Hong Kong Chinese version 2) (IPSS) in Chinese male patients with benign prostatic hyperplasia (BPH) under secondary care. Methods: A prospective longitudinal study was done by interviewing subjects at baseline, at 2 week after baseline for assessing test–retest reliability and at 26 week after baseline for assessing responsiveness. All subjects were interviewed to complete a structured questionnaire including IPSS, Short Form-12 Health Survey version 2 (SF-12v2) and Depression Anxiety Stress Scale (DASS). Results: The IPSS HRQOL score had weak correlations with SF-12v2 summary and DASS domain scores. For reliability analysis, Cronbach’s alpha coefficient was 0.90 for the seven symptom-related items. The intraclass correlation coefficients of the IPSS total symptom score and HRQOL score were 0.90 and 0.86, respectively. For sensitivity, statistically significant differences were detected between the subjects with BPH and those without for IPSS total symptom score (effect size=0.68) but not the IPSS HRQOL score. The areas under ROC curves for the IPSS total symptom and HRQOL scores were 0.67 and 0.60, respectively. Conclusions: The IPSS was valid, reliable instrument in Chinese patients with BPH. The IPSS total symptom score, but not the HRQOL score, is sensitive in differentiating subgroups

Design of bio-nanosystems for oral delivery of functional compounds

Nanotechnology has been referred to as one of the most interesting topics in food technology due to the potentialities of its use by food industry. This calls for studying the behavior of nanosystems as carriers of biological and functional compounds aiming at their utilization for delivery, controlled release and protection of such compounds during food processing and oral ingestion. This review highlights the principles of design and production of bio-nanosystems for oral delivery and their behavior within the human gastrointestinal (GI) tract, while providing an insight into the application of reverse engineering approach to the design of those bio-nanosystems. Nanocapsules, nanohydrogels, lipid-based and multilayer nanosystems are discussed (in terms of their main ingredients, production techniques, predominant forces and properties) and some examples of possible food applications are given. Phenomena occurring in in vitro digestion models are presented, mainly using examples related to the utilization of lipid-based nanosystems and their physicochemical behavior throughout the GI tract. Furthermore, it is shown how a reverse engineering approach, through two main steps, can be used to design bio-nanosystems for food applications, and finally a last section is presented to discuss future trends and consumer perception on food nanotechnology.Miguel A. Cerqueira, Ana C. Pinheiro, Helder D. Silva, Philippe E. Ramos, Ana I. Bourbon, Oscar L. Ramos (SFRH/BPD/72753/2010, SFRH/BD/48120/2008, SFRH/BD/81288/2011, SFRH/BD/80800/2011, SFRH/BD/73178/2010 and SFRH/BPD/80766/2011, respectively) are the recipients of a fellowship from the Fundacao para a Ciencia e Tecnologia (FCT, POPH-QREN and FSE Portugal). Maria L. Flores-Lopez thanks Mexican Science and Technology Council (CONACYT, Mexico) for PhD fellowship support (CONACYT Grant number: 215499/310847). The support of EU Cost Actions FA0904 and FA1001 is gratefully acknowledged

Mucinous adenocarcinoma of renal pelvis and villous adenoma of bladder after a caecal augmentation of bladder

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A case-controlled comparison of single-site access versus conventional three-port laparoscopic appendectomy

Background: The aim of this study was to compare patients who underwent single-site access laparoscopic appendectomy (SSALA) to those who underwent conventional three-port laparoscopic appendectomy (TPLA) in a case-controlled manner. Methods: Consecutive patients who underwent SSALA for suspected acute appendicitis between April and September 2009 were retrospectively compared to those who underwent TPLA between January and December 2008 in a case-controlled manner. The patients were matched for age, gender, and pathological findings. The main outcome measurements included postoperative recovery, morbidities, and mortalities. Results: During the study period, a total of 30 patients underwent SSALA and these were matched with 60 TPLA patients. There were no significant differences in the mean operative time, hospital stay, and 30-day morbidity rate between the two groups. None of the patients required conversion. Two patients with significant contamination and abscess collection noted during SSALA required a relaparotomy for peritoneal lavage and adhesiolysis due to prolonged ileus. Conclusions: SSALA is feasible and the perioperative outcome was comparable to that of TPLA. However, future prospective studies will need to evaluate whether SSALA can adequately tackle patients with significant peritoneal contamination. © 2010 Springer Science+Business Media, LLC.link_to_subscribed_fulltex

Push-type percutaneous endoscopic gastrostomy with ultrathin endoscope in patients with severe trismus or obstruction due to head and neck cancers: A case series

Aim: Endoscopically-placed, push-type percutaneous endoscopic gastrostomies (PEG) have recently been made possible through the use of a gastropexy device. However, the safety and efficacy of the procedure in patients suffering from severe trismus or malignant obstruction due to head and neck cancers have rarely been reported. The aim of this study was thus to investigate the feasibility, safety and risk of endoscopic push-type PEG in this group of patients. Patients and Methods: Consecutive patients who were indicated for PEG and suffered from severe trismus or malignant obstruction due to head and neck cancers, precluding the introduction of a 9.8mm oesophagogastroduodenoscope were included. Push-type PEG was performed under endoscopic control with a 5-mm endoscope and the loop fixture device. Results: Eleven patients had push-type PEG performed under conscious sedation. All procedures were successful, and minor complications occurred in one patient with a dislodged gastrostomy tube and another with wound infection. There were no mortalities or major morbidities related to the procedure. Conclusions: Push-type PEG with gastropexy inserted under endoscopic control by an ultrathin endoscope is a feasible alternative to open gastrostomy in patients with severe trismus or pharyngeal obstruction. © 2011 The Authors. Surgical Practice © 2011 College of Surgeons of Hong Kong.link_to_subscribed_fulltex