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Background: The oro-facial modification occurring in systemic sclerosis are detrimental for patients, but the therapeutic options are limited., Objectives: This systematic review aimed to perform an up-to-date appraisal of the literature focusing on fat grafting and other adipose stem cell-based therapies for the treatment of facial systemic sclerosis, determining its efficacy and safety, and investigating the current practice for treatment optimization., Methods: The review was prospectively registered in PROSPERO (CRD42021286268) and followed the PRISMA principles. Multiple databases were searched and only original studies were included., Results: Over the 12 studies matching the inclusion criteria, 174 patients were treated. Of them, 87.3% (n = 152) were considered to have improved. The complications, graded with the Clavien-Dindo grading system, were grade 1 (no treatment required) or 2 (antibiotic required). Patients received an average of 2.5 ± 3.68, median 1.35 (range 1-14), lipotransfer procedures. Overall, an amount of 14.60 ± 6.24 ml was injected in the overall facial area, median 16 (range 27-3) ml. The average interval between procedures was 5.30 ± 2.04 months, with a median of 6 (range 3-6.91) months. At the time of inclusion, patients were diagnosed with scleroderma disease on an average 14.7 ± 7.35 years., Conclusions: Fat grafting for facial systemic sclerosis is effective and safe. The definitive durability of the effect is still unclear, and the optimal number of treatments must be determined to define a precise evidence-based protocol. The body of evidence is highly fragmented, with disagreement in the surgical technique used and outcome assessment, making results from different studies often not comparable. The level of evidence is overall low or very low, and the risk of bias of published studies is overall medium to high. RCTs are urgently needed., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Aesthetic Society.)

Purpose: Literature on antipsychotic medication adherence in early psychosis primarily assessed adherence behaviors and focused on young patients. There is a paucity of research investigating negative medication attitude and its determinants in the early illness course, particularly in older-aged sample. We aimed to examine prevalence and correlates of medication non-adherence behaviors and negative medication attitudes separately in adult patients with early psychosis., Methods: One hundred ninety-nine Chinese early psychosis patients aged 26-55 years who had received three-year treatment for first psychotic episode in Hong Kong were examined. Assessments encompassing socio-demographics, premorbid adjustment, clinical and treatment profiles, self-stigma and therapeutic alliance were conducted. Patients were evaluated with Medication Compliance Questionnaire, which is a modified Chinese-translated version of Medication Adherence Rating Scale and includes items measuring adherence behaviors and attitudes towards medications., Results: Rates of medication non-adherence and negative attitude towards medications were 38.7% and 50.8%, respectively. Multivariate regression analysis showed that more severe positive symptoms, greater self-stigma and negative medication attitude were independently associated with medication non-adherence. Negative attitude towards medications was significantly associated with younger age, higher educational attainment, diagnosis of other psychotic disorders, poorer insight, greater self-stigma and less satisfaction with communication with healthcare staff, which represented an index reflecting suboptimal therapeutic alliance., Conclusion: Antipsychotic non-adherence and negative medication attitudes are frequently observed in adult early psychosis patients. Our findings indicate that poor insight, elevated self-stigma and suboptimal therapeutic alliance may constitute potential treatment targets for promoting medication adherence and rectifying negative medication attitudes in the early illness stage., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

Objective: To investigate the prevalence of obstructive sleep apnea syndrome (OSAS) risk and related risk factors among children and adolescents of Hong Kong with cleft lip and/or palate (CL/P)., Design: Retrospective survey study adopting three questionnaires, obstructive sleep apnea-18 (OSA-18), pediatric sleep questionnaire-22 (PSQ-22), and modified Epworth Sleepiness Scale (ESS)., Settings: Multicenter study in two public hospitals., Patients: A total of 351 Chinese children and adolescents with non-syndromic CL/P (6-18-year-old, 57% males) visited between September 2017 and November 2019, with primary palatal repair surgery done before 3-year-old., Main Outcome Measure: Positive OSAS risk was determined based on cut-off ≥60 for OSA-18, ≥8 for PSQ-22, and >8 for ESS. Age, sex, overweight presence, cleft type, embryonic secondary palate involvement, palatal repair surgery, palatal revision surgery, and orthodontic treatment were analyzed as possible risk factors., Results: A total of 9.5% of patients had positive OSAS risk based on OSA-18, 13.6% based on PSQ-22, and 13.2% according to ESS. A higher prevalence of patients with positive OSAS risk was of younger age (OSA-18, p  = .034), had cleft involving embryonic secondary palate (PSQ-22, p  = .009), and history of fixed orthodontic treatment (ESS, p  = .002). The regression model identified only involvement of embryonic secondary palate as a risk factor (PSQ-22, odds ratio = 3.7, p  = .015)., Conclusions: OSAS risk among children and adolescents of Hong Kong with CL/P was 9.5% to 13.6%. Patients at higher risk were those with cleft involving embryonic secondary palate. OSAS risk assessment may be influenced by different aspects of the disease spectrum, and a multimodal approach should be considered for such assessment.

Mutation in SP7, encoding the osteoblast-specific transcription factor SP7 (also known as osterix), has been described to cause osteogenesis imperfecta (OI) type XII. However, the exact dental phenotype has not been well described. We report the detailed dental manifestation of a boy known to have OI type XII, presented with impacted dentition, necessitating combined oral and maxillofacial surgical and orthodontic treatment. This case also highlighted the need of multidisciplinary team assessment in this group of children., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

COVID-19 not only threatens people's physical health, but also creates disruption in work and social relationships. Parents may even experience additional strain resulting from childcare responsibilities. A total of 129 parents participated in this study. Parents of children with developmental disorders showed higher levels of parenting stress, depressive symptoms, and anxiety symptoms than did parents of children with typical development. Parenting stress and health worries were positively related to mental health symptoms. The association between having a child with developmental disorders and mental health symptoms was mediated by parenting stress. This study provides a timely investigation into the stress and mental health of parents during the COVID-19 pandemic. Implications on web-based parenting skills interventions, online psychological support services, and family-friendly policy initiatives are discussed., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The aim of this study was to determine whether there is an increase in the reading fluency and accuracy of three lower performing third-graders after participating in a canine-assisted read-aloud program, as well as an increase in the relaxation level during and after the program. This study employed a pre-test-post-test design to test the hypotheses that gains would be made in both reading fluency and reading accuracy upon completion of the program. The three grade 3 students were assessed by the Chinese Character Reading Test and the Reading Fluency Test. During the intervention, they read to a trained canine in the presence of a handler. Three days after the completion of the seven 20-min interventions, the participants were assessed by the two standardized reading tests a second time. Heart rate variability (HRV) responses to the pre-test, the intervention and the post-test were recorded. The three grade 3 students attained a higher level of relaxation while reading to the dog and increased their reading fluency after the reading sessions. These results provided preliminary evidence that the canine-assisted read-aloud program can increase the reading performance of children with lower performance. Implications for future research and reading programs will be discussed.

Objective: To determine the efficacy of 2 types of antimicrobial privacy curtains in clinical settings and the costs involved in replacing standard curtains with antimicrobial curtains., Design: A prospective, open-labeled, multicenter study with a follow-up duration of 6 months., Setting: This study included 12 rooms of patients with multidrug-resistant organisms (MDROs) (668 patient bed days) and 10 cubicles (8,839 patient bed days) in the medical, surgical, neurosurgical, orthopedics, and rehabilitation units of 10 hospitals., Method: Culture samples were collected from curtain surfaces twice a week for 2 weeks, followed by weekly intervals., Results: With a median hanging time of 173 days, antimicrobial curtain B (quaternary ammonium chlorides [QAC] plus polyorganosiloxane) was highly effective in reducing the bioburden (colony-forming units/100 cm2, 1 vs 57; P < .001) compared with the standard curtain. The percentages of MDRO contamination were also significantly lower on antimicrobial curtain B than the standard curtain: methicillin-resistant Staphylococcus aureus, 0.5% vs 24% (P < .001); carbapenem-resistant Acinetobacter spp, 0.2% vs 22.1% (P < .001); multidrug-resistant Acinetobacter spp, 0% vs 13.2% (P < .001). Notably, the median time to first contamination by MDROs was 27.6 times longer for antimicrobial curtain B than for the standard curtain (138 days vs 5 days; P = .001)., Conclusions: Antimicrobial curtain B (QAC plus polyorganosiloxane) but not antimicrobial curtain A (built-in silver) effectively reduced the microbial burden and MDRO contamination compared with the standard curtain, even after extended use in an active clinical setting. The antimicrobial curtain provided an opportunity to avert indirect costs related to curtain changing and laundering in addition to improving patient safety.

Purpose: Submental flap is gaining popularity for head and neck reconstruction. We have reported in 2007 our early experience of using submental flap for aggressive orofacial malignancy. Novel flap design and application is described in this updated series., Materials and Methods: 15 patients who had received submental flap reconstruction after extirpation of newly diagnosed aggressive orofacial lesions were retrieved. The details of the flap harvest was studied for flap size, inclusion of mylohyoid muscle, antegrade versus retrograde blood supply, and compared with our previous series., Results: The dimension of flap skin paddle was 30cm 2 (range 20-72). Retrograde pedicle flow was used in 2(13.3%) patients. Mylohyoid muscle was included in the flap in 6(40%) patients. There was no total flap necrosis while partial flap necrosis occurred in 1 patient(6.7%). There was a significant increase of inclusion of mylohyoid muscle to the flap in this series (p = 0.02). Novel techniques including double-paddled flap skin to resurface full-thickness defect and chimeric osteocutaneous mandible submental flap for maxillary defect were successfully performed., Conclusions: Submental flap is a viable reconstructive option in selected patients with aggressive orofacial malignancy. The indications are expanding and its technical modification is evolving and resulting in more innovative applications., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Purpose: Lymph node density(LND) has been shown to be a better prognosticator than conventional nodal classification to predict prognosis for squamous cell carcinoma(SCC) of the oral cavity. However, studies focusing on subsites of oral cancer are meager. The role of LND for buccal SCC was evaluated in this study., Methods: A total of 39 patients with buccal SCC primarily treated surgically with neck dissection were identified. LND was defined as the number of positive nodes over the number of nodal yield. The cut-off of LND was ≤0.07 or >0.07. Patient demographic data and clincopathologic parameters were described. Survival was expressed by Kaplan-Meier method and correlation with survival is analyzed with log-rank test. IBM SPSS Statistics version 22 was used for data computation., Results: The median follow-up was 79.0months and median nodes removed was 23 (range 8-93). Positive nodal involvement was found in 19(48.7%) patients. The 5-year and 10-year OS were 67.4% and 42.5% whilst for DSS were 69.2% and 65.5%, respectively. When pT-, pN-, LND-classification and AJCC stage were analyzed for the whole series, only pN- (p=0.006) and LND-classification (p=0.002) were significant factors for OS, while pT-, pN-, LND-classification and AJCC stage were all significant factors for DSS. When only cases with positive nodal spread were considered, the pN-classification (pN1 vs pN2) was not a significant risk factor for either OS (p=0.075, HR 3.10(CI 0.89-10.76)) and DSS (p=0.074, HR 3.58(CI 0.88-14.56)). By contrast, LND-classification (≤0.07 vs >0.07) remained a significant predictor for OS (p=0.03, HR 3.95(CI 1.15-13.63)), but not for the DSS (p=0.112, HR 2.92(CI 0.78-10.99))., Conclusion: The prognostic value of LND on buccal SCC is supported in this study. The results also suggest that LND is better than the conventional pN-classification to predict OS. Further studies on LND with big sample size for buccal SCC or other subsites of OSCC are worthwhile., (Copyright © 2017 Elsevier Inc. All rights reserved.)

HPV plays a role in the development of a portion of head and neck squamous cell carcinoma (HNSCC), but only limited information on its role in southern Chinese population is available. A multicenter case-control study was conducted. HPV type, viral integration, E6/7 mRNA expression status, and TP53 mutation were determined. A total of 228 HNSCC were recruited including 137 (60.1%) oral SCC, 34 (14.9%) oropharyngeal SCC, 31 (13.6%) laryngeal SCC, 21 (9.2%) hypopharyngeal SCC, and 5 (2.2%) lip and paranasal sinus SCC. High-risk HPV infection was found in 7.5% (17/228) of HNSCC, but only a small proportion of samples had evidence of viral integration (5.3%, 12/228) or E6/7 mRNA expression (4.4%, 10/228). HPV infection with oncogenic phenotype (integration and E6/7 mRNA expression) was significantly more common in oropharyngeal SCC than controls (9/34, 26.5% vs. 0/42, 0.0%, P < 0.001). Smoking showed a significant association with HNSCC, oropharyngeal SCC, and laryngeal SCC. TP53 mutation was associated with HNSCC (P < 0.001). Older age, TP53 mutation, and HPV16 infection with oncogenic phenotypes were independently associated factors for HNSCC with odds ratios of 1.03 (1.02-1.05), 3.38 (1.71-6.66), and 9.19 (1.13-74.68), respectively. High-risk HPV infection of head and neck mucosa is not uncommon in the Hong Kong population. This study found that 26-30% of oropharyngeal carcinoma was associated with HPV infection, mostly HPV16, and that smoking which predisposes to TP53 mutations was another important risk factor., (© 2015 Wiley Periodicals, Inc.)

Context: Although research has shown that animal-assisted play therapy (AAPT) is associated with increased positive social behaviors in children with autism, the related literature on AAPT and autism is very limited., Objectives: The study tested the effectiveness of AAPT in increasing the social communication of a boy with autism. The treatment's effects on specific types of social communication were also investigated., Design: An A-B-A single-subject design was adopted to examine treatment effectiveness. Follow-up assessments were made at 1 mo posttreatment., Setting: The videotaped treatment sessions were held in the multipurpose room of the participant's school., Participant: A 7-y-old boy who had a diagnosis of autism and mild-grade intellectual disability participated in the study., Intervention: AAPT was implemented in 20-min sessions held 3 ×/wk. The 14 AAPT sessions occurred in 4 phases, covering child-dog relationship building and interaction in the presence of the therapist, with the diminishing presence of the dog occurring in phase 4., Outcome Measures: Naturally occurring social behaviors were measured in 3 baseline sessions, during the 14 AAPT sessions, during 3 posttreatment sessions, and again during 3 follow-up sessions. Momentary time sampling was used to estimate the frequency of target behaviors, using a 15-s interval. Behavioral categories were checked at every interval during each 20-min session in all 23 sessions., Results: The study showed that the boy's social communication increased during treatment and remained higher than baseline at follow-up. An analysis of specific types of social communication showed that the benefits of AAPT were most apparent in the joint-attention and waiting behaviors., Conclusions: The findings provide support for using AAPT as an intervention to facilitate the social communication of children with autism.

Background: Socioeconomic disadvantage is associated with an increased risk of developing heart failure and with inferior health outcomes following diagnosis., Methods: Data for hospitalisations and deaths due to heart failure in the Sydney metropolitan region were extracted from New South Wales hospital records and Australian Bureau of Statistics databases for 1999-2003. Standardised rates were analysed according to patients' residential local government area and correlated with an index of socioeconomic disadvantage., Results: Eight of the 13 local government areas with standardised separation rate ratios significantly higher than all NSW, and those with the six highest standardised separation rate ratios, were in Greater Western Sydney. Rates of heart failure hospitalisations per local government area were inversely correlated with level of socioeconomic status., Conclusions: Higher rates of heart failure hospitalisations among residents of socioeconomically disadvantaged regions within Sydney highlight the need for strategies to lessen the impact of disadvantage and strategies to improve cardiovascular health., (Copyright © 2014. Published by Elsevier B.V.)

Reconstruction of full-thickness buccal defect is challenging as two linings need to be addressed. Either two different flaps or double-paddle for one free flaps are necessary for this defect. The prolonged operation might not be tolerated by patients because of advanced age or medical comorbidity. A 77-year-old gentleman, with significant medical comorbidity, presented with a 4.0 × 4.5 cm ulcerative mass due to squamous cell carcinoma arising from the left buccal mucosa. The tumor extended to the left cheek skin. There was no palpable neck node. CT scan did not show any bony erosion or suspicious neck node. Full-thickness resection of the tumour was undertaken. For the full-thickness buccal defect, a bi-paddled pedicled submental flap after de-epithelialization of the flap skin was used for both the cutaneous and mucosal resurfacing. The flap survived completely and patient recovered smoothly. The surgery is simple and operation time is much shorter than free flap reconstruction. This modified utilization of submental flap simplifies the closure of complicated oro-facial wound.

Objective: To determine the prevalence, risk factors, and molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) colonization at the time of admission to acute medical units and to develop a cost-effective screening strategy., Methods: Nasal and groin screening cultures were performed for patients at admission to 15 acute medical units in all 7 catchment regions in Hong Kong. All MRSA isolates were subjected to spa typing., Results: The overall carriage rate of MRSA was 14.3% (95% confidence interval [CI], 13.5-15.1). MRSA history within the past 12 months (adjusted odds ratio [OR], 4.60 [95% CI, 3.28-6.44]), old age home residence (adjusted OR, 3.32 [95% CI, 2.78-3.98]), and bed-bound state (adjusted OR, 2.19 [95% CI, 1.75-2.74]) were risk factors selected as MRSA screening criteria that provided reasonable sensitivity (67.4%) and specificity (81.8%), with an affordable burden (25.2%). spa typing showed that 89.5% (848/948) of the isolates were clustered into the 4 spa clonal complexes (CCs): spa CC1081, spa CC032, spa CC002, and spa CC4677. Patients colonized with MRSA spa types t1081 (OR, 1.77 [95% CI, 1.49-2.09]) and t4677 (OR, 3.09 [95% CI, 1.54-6.02]) were more likely to be old age home residents., Conclusions: MRSA carriage at admission to acute medical units was prevalent in Hong Kong. Our results suggest that targeted screening is a pragmatic approach to increase the detection of the MRSA reservoir. Molecular typing suggests that old age homes are epicenters in amplifying the MRSA burden in acute hospitals. Enhancement of infection control measures in old age homes is important for the control of MRSA in hospitals.

We integrated complementary and alternative medicine (CAM)-related content into selected core courses in our master's-level curriculum. To facilitate students' application of the content, we developed evidence-based online case studies and evaluated their effectiveness by comparing students' pretest and posttest scores on multiple-choice quizzes. Findings suggest that evidence-based online case studies are an effective strategy for teaching graduate nursing students about the clinical issues surrounding patients' use of CAM therapies., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objective: To study the epidemiology of Candida bloodstream infection in the Intensive Care Unit., Design: Retrospective study., Setting: A 22-bed, mixed medical and surgical Intensive Care Unit of a 1400-bed university teaching hospital in Hong Kong., Patients: All adult patients (>18 years) who had at least one blood culture positive for Candida., Results: During the 9 years of the study period, there were 128 patients with episodes of candidaemia (point prevalence, 9.6 per 1000 Intensive Care Unit admissions), 72 entailed albicans candidaemia and 56 non-albicans candidaemia. Albicans was still the predominant species, but the incidence of tropicalis was increasing. The median lengths of hospital and Intensive Care Unit stays prior to taking of the culture revealing candidaemia were 15 and 6 days, respectively. In all, 61% of patients did not have Candida colonisation within 2 weeks of their candidaemia. The main anti-fungal agents used were fluconazole and amphotericin B, but only 89 (70%) of the patients received appropriate anti-fungal treatment. Intensive Care Unit and hospital mortalities were 70% and 78%, respectively. Patients who did not receive appropriate treatment within 3 days had a worse outcome than those who did., Conclusions: Our data showed a high point prevalence of candidaemia in the Intensive Care Unit. Albicans was still the predominant species. Candidaemia occurred early during Intensive Care Unit stay, and a significant proportion of patients did not have prior fungal colonisation. Candidaemia in the Intensive Care Unit was associated with high morbidity and mortality. Many patients did not receive appropriately early anti-fungal therapy, and endured higher mortality than in the remainder.

Objective: This is the first community-based epidemiological study examining the prevalence of suicidal behaviors, their transitional pathways, and their relationship with mental disorders in metropolitan China., Method: Suicidal behaviors, including ideation, plans, and attempts were assessed by face-to-face household interviews among 5201 respondents in Beijing and Shanghai in 2001-2002. Lifetime prevalence and risk factors were examined using multivariate discrete-time survival models., Results: The lifetime prevalence estimates of suicidal ideation, plans, and attempts were 3.1%, 0.9%, and 1.0% respectively. Among suicide ideators, the conditional probability of ever making a plan and an attempt was 29.5% and 32.3% respectively. Progression from ideation to plan and attempt was the highest during the first year after onset. Suicide attempt was predicted by young adulthood, being unmarried, recent onset of ideation and plan, and the presence of mental disorders, especially mood disorder., Conclusion: Suicidal behaviors in metropolitan China exhibit a low prevalence and an epidemiological profile resembling that found in Western countries.

Background: The submental flap was described for head and neck reconstruction more than a decade ago. Its application is confined mainly to nonmalignant diseases or low-grade malignancies, as the submental flap resides in the level I lymphatic drainage region of the neck. The authors report the use of the submental flap for soft-tissue reconstruction in a selected group of patients with aggressive orofacial cancer., Methods: From March of 2003 to September of 2005, 10 patients (nine with intraoral squamous cell carcinoma and one with facial angiosarcoma) underwent submental flap reconstruction after surgical extirpation of aggressive orofacial malignancies. The indications were severe comorbidity, old age, the presence of another incurable cancer, and/or the patient's skepticism about undergoing a free flap operation., Results: Of the surviving patients, the median follow-up was 21 months (range, 2 to 37 months). There were no cases of total flap failure, but partial necrosis occurred in two cases. Three patients experienced tumor recurrence, but only one case might have been related to use of the submental flap. Postoperative oral function, in terms of swallowing and speech, was well preserved; conventional dentures were fabricated for four patients., Conclusions: In selected patients with aggressive orofacial cancer, the submental flap is an expedient alternative to free tissue transfer for reconstruction. Nonetheless, indiscriminate use might compromise the oncological outcome, so it cannot be regarded as a standard method of treatment.

Objective: There has been no community-based research on treatment delay among people with mental disorders in China. This study examines lifetime treatment and treatment delay in metropolitan China., Method: A multi-stage probability survey of 5201 respondents was administered in Beijing and Shanghai. Age of first treatment contact after onset of each of the three lifetime DSM-IV/CIDI disorder classes was compared with retrospective information on age of disorder onset. Length and predictors of treatment delay were examined using survival analysis., Results: Survival curves estimate that 44.7%, 25.7%, and 7.9% of people with anxiety, substance, and mood disorders, respectively, will ever make treatment contact. Delays in first treatment contact of anxiety (21 years) and substance (17 years) disorders are longer than that of mood disorders (1 year). These delays are largely unrelated to sociodemographic variables., Conclusion: Failure to receive treatment is a pervasive phenomenon among people with mental disorders in metropolitan China.

Carbofuran (2,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate) (CBF) is a widely used insecticide. Traditional methods like hydrolysis and direct photolysis cannot remove CBF effectively. In this study, the photodecay of 0.1 mM CBF in UV/H2O2, UV/S2O8(2-), and UV/H2O2/S2O8(2-) and sequential addition of a second oxidant were studied under UV light at 254 nm. The degradations of CBF follow pseudo-first-order decay kinetics. Direct photolysis was slow, but the corresponding degradation rate was increased with the addition of hydrogen peroxide (H2O2) or potassium peroxydisulfate (K2S2O8). In the UV/H2O2 reaction, the optimum reaction rate was 0.9841 min-1 at 10 mM H2O2 (pH 7); however, retardation is observed if H2O2 is overdosed. Such retardation is not observed in the UV/S2O8(2-) system, but a nonlinear increment of removal efficiency is identified. The UV/H2O2/S2O8(2-) process on the other hand shows the best performance in CBF degradation, but it has a less effective mineralization than that of the sole UV/S2O8(2-) reaction.

Purpose: Contralateral neck failure after therapy for squamous cell carcinoma of the oral cavity and oropharynx has rarely been studied in detail. We aimed to examine the pattern and outcome of contralateral neck relapse and possible predictive clinicopathologic factors., Patients and Methods: Seventy-three patients undergoing surgery for cancer of oral cavity/oropharynx with curative intent were recruited from the hospital head and neck cancer registry. The age, gender, tumor site, primary tumor laterality, TNM status, clinical N status, pathologic T status, ipsilateral pathologic N status, tumor stage, status of residual disease, histopathologic differentiation, postoperative radiotherapy, local relapse, distant relapse, extracapsular spread of lymph node metastasis and neck dissection were evaluated for association with contralateral neck relapse., Results: Seven patients developed ipsilateral, 5 patients developed contralateral, and 3 patients developed bilateral neck recurrence after therapy. Only 1 patient with contralateral or bilateral neck relapse survived after salvage therapy. Ipsilateral positive nodal status was the only significant clinicopathologic parameter associated with contralateral neck relapse, which occurred rather commonly in well-lateralized tumors., Conclusion: Contralateral and ipsilateral neck relapses are similar in occurrence. Pathologic positive nodal status is associated with a higher incidence of contralateral neck relapse. Aggressive and comprehensive adjuvant radiotherapy to the neck plus close surveillance in the first 2 years postoperatively might curtail the frequency and mortality due to contralateral neck failure.

A novel heterobimetallic alkynyl-bridged complex, [Re(bpy)(CO)(3)(C[triple bond]C[bond]C(6)H(4)[bond]C[triple bond]C)Fe(C(5)Me(5))(dppe)], 1, and its oxidized species, [Re(bpy)(CO)(3)(C[triple bond]C[bond]C(6)H(4)[bond]C[triple bond]C)Fe(C(5)Me(5))(dppe)][PF(6)], 2, have been synthesized and their X-ray crystal structures determined. A related vinylidene complex, [Re(bpy)(CO)(3)(C[triple bond]C[bond]C(6)H(4)[bond](H)C[double bond]C)Fe(C(5)Me(5))(dppe)][PF(6)], 3, has also been synthesized and characterized. The cyclic voltammogram of 1 shows a quasireversible reduction couple at -1.49 V (vs SCE), a fully reversible oxidation at -0.19 V, and a quasireversible oxidation at +0.88 V. In accord with the electrochemical results, density-functional theory calculations on the hydrogen-substituted model complex Re(bpy)(CO)(3)(C[triple bond]C[bond]C(6)H(4)[bond]C[triple bond]C)Fe(C(5)H(5))(dHpe) (Cp = C(5)H(5), dHpe = H(2)P[bond](CH(2))(2)[bond]PH(2)) (1-H) show that the LUMO is mainly bipyridine ligand pi* in character while the HOMO is largely iron(II) d orbital in character. The electronic absorption spectrum of 1 shows low-energy absorption at 390 nm with a 420 nm shoulder in CH(2)Cl(2), while that of 2 exhibits less intense low-energy bands at 432 and 474 nm and additional low-energy bands in the NIR at ca. 830, 1389, and 1773 nm. Unlike the related luminescent rhenium(I)-alkynyl complex [Re(bpy)(CO)(3)(C[triple bond]C[bond]C(6)H(4)[bond]C[triple bond]C[bond]H)], 4, complex 1 is found to be nonemissive, and such a phenomenon is attributed to an intramolecular quenching of the emissive d pi(Re) --> pi*(bpy) (3)MLCT state by the low-lying MLCT and LF excited states of the iron moiety. Interestingly, switching on of the luminescence property derived from the d pi(Re) --> pi*(bpy) (3)MLCT state can be demonstrated in the oxidized species 2 and the related vinylidene analogue 3 due to the absence of the quenching pathway.

We investigated the average operating time and extent of intra-operative blood loss in orthognathic surgeries performed using induced hypotensive general anaesthesia, with the intention of devising a practical guideline for blood unit preparation for these procedures. We prospectively studied 32 Chinese patients undergoing surgery to correct dentofacial deformities at a public hospital in Hong Kong from 1 December 1997 to 1 December 1998. Most patients (72. 4%) needed double-jaw surgery. The mean estimated blood loss was approximately 617.6 mL. The blood loss during simple Le Fort I osteotomies was about half that of multiple segmentalised osteotomies. For mandibular ramus osteotomies, the mean blood loss and operating time for were approximately 280 mL and 2 hours, respectively; for anterior mandibular osteotomies, the corresponding values were 171.3 mL and 1 hour 13 minutes. The average drop in the haematocrit value was 15.4%, and the crossmatch to transfusion ratio was 29. A bivariate correlation test between the blood loss and operating time gave a strong correlation (P<0.01), as did blood loss with a drop in haematocrit value (P<0.01). Orthognathic surgeries are thus safe and predictable in terms of intra-operative blood loss and operating time, and a 'type, screen, and save' policy for blood unit preparation is more appropriate than a 'crossmatch' policy.

Objective: To compare patient-controlled sedation with 1-mg increments of midazolam at 1-min intervals with 0.1-mg increments of midazolam without a lock-out interval., Design: Randomized cross over study., Subjects: 32 patients aged 17-35 years having third molars removed., Results: Doses of midazolam obtained, degree of sedation and operating conditions were similar in the two groups. The demands far exceeded the increments actually received by patients obtaining 0.1-mg increments. Some were extremely sedated with both techniques., Conclusions: In this age group, there were no significant advantages or disadvantages of one technique over the other. Patients obtained the degree of sedation they required to undergo the operation by pressing the button independently of the dose or incremental interval. So-called 'true' patient-controlled sedation is a misnomer. The cut-off interval proved to be an extremely important safety feature.

The most common site of haemorrhage in maxillary osteotomies is the posterior maxilla. Better understanding of the anatomy in this region may minimize possible vascular complications. The aim of the study was to study the osteology of the posterior maxillary region and establish clinical safety guidelines for the Le Fort I osteotomy Thirty human dry skulls were selected and assessed by a combination of direct inspection, computerized imaging and computed tomography (CT) scan analysis. Results showed that the presence of maxillary third molars influenced the transverse angulation of the posterior vertical cut. Synostosis of the pterygomaxillary junction was noted in 12% of samples. The mean length of the medial sinus wall from the piriform rim to the descending palatine canal at the Le Fort I level was 34 mm. The three-dimensional CT-reconstructed descending palatine canal ran at 60 degrees anteroinferiorly to the palatine plane and slightly medially to the exit through the greater palatine foramen.

Aims: To evaluate the effectiveness of oral vancomycin in the prophylaxis of necrotising enterocolitis in preterm, very low birthweight infants., Methods: A prospective, double blind, randomised, placebo controlled study in a tertiary referral centre of a university teaching hospital was conducted on 140 very low birthweight infants consecutively admitted to the neonatal unit. The babies were randomly allocated to receive oral vancomycin (15 mg/kg every 8 hours for 7 days) or an equivalent volume of placebo solution. Prophylaxis was started 24 hours before the start of oral feeds. All suspected cases of necrotising enterocolitis were investigated with a full sepsis screen and serial abdominal radiographs. Necrotising enterocolitis was diagnosed and staged according to modified Bell's criteria., Results: Nine of 71 infants receiving oral vancomycin and 19 of 69 infants receiving the placebo solution developed necrotising enterocolitis (p = 0.035). Infants with necrotising enterocolitis were associated with a significant increase in mortality (p = 0.026) and longer duration of hospital stay (p = 0.002)., Conclusions: Prophylactic oral vancomycin conferred protection against necrotising enterocolitis in preterm, very low birthweight infants and was associated with a 50% reduction in the incidence. However, widespread implementation of this preventive measure is not recommended, as it would only be effective in necrotising enterocolitis caused by Gram positive organisms and could increase the danger of the emergence of vancomycin resistant or dependent organisms. Its use should be restricted to a high prevalence nursery for a short and well defined period in a selected group of high risk patients.

The LID strain of polyomavirus differs from other laboratory strains in causing a rapidly lethal infection of newborn C3H/Bi mice. This virulent behavior of LID was attenuated by dilution, yet at sublethal doses LID was able to induce tumors at a high frequency, like its parent virus PTA. By constructing and assaying LID-PTA recombinant viruses and by DNA sequencing, the determinant of virulence in LID was mapped to the major viral capsid protein, VP1. The VP1s of LID and PTA differed at two positions: at 185, LID has phenylalanine and PTA has tyrosine, and at 296, LID has alanine and PTA has valine. Results obtained with viruses constructed by site-directed mutagenesis showed that alanine at position 296 is sufficient to confer a fully virulent phenotype regardless of which amino acid is at position 185. However, with valine at position 296, an effect of phenylalanine at position 185 is apparent, as this virus possesses an intermediate level of virulence. A crystal structure of polyomavirus complexed with 3'-sialyl lactose previously indicated van der Waals contacts between the side chain of valine 296 and the sialic acid ring (T. Stehle, Y. Yan, T. L. Benjamin, and S. C. Harrison, Nature [London] 369:160-163, 1994). When this interaction was modeled with alanine, these contacts were greatly reduced. Direct confirmation that the substitutions in VP1 affected receptor binding was obtained by studying virus hemagglutination behavior. The ensemble of results are discussed in terms of the idea that a lower affinity of the virus for its receptor can result in more rapid spread and increased pathogenicity.

The actions on [3H]noradrenaline release of chlordiazepoxide and FG 7142 were investigated in rat hippocampal synaptosomes. The release evoked by GABA, an action mediated by GABAA receptors, was enhanced by chlordiazepoxide and depressed by FG 7142. K+-evoked release, however, was depressed by both chlordiazepoxide and FG 7142 and occurred in the absence of GABA. The actions on both GABA-evoked and K+-evoked release were blocked by Ro 15-1788. The results suggest that the distinction between agonist and inverse agonist applies to the GABA-dependent but not to the GABA-independent action of benzodiazepines.

Uptake, synthesis, storage, and release of gamma-aminobutyric acid (GABA) are some of the characteristic properties of GABA-ergic neurons. In the present study, we have used these properties as physiological probes to follow the emergence and maturation of GABA-ergic neurons during postnatal development of the rabbit retina. There is autoradiographic, immunocytochemical, and pharmacological evidence that some amacrine cells and certain neurons in the ganglion cell layer probably use GABA as the neurotransmitter. These neurons take up GABA, contain the GABA-synthesizing enzyme L-glutamic acid decarboxylase (GAD, EC 4.1.1.15), and release the accumulated GABA by a CA++-dependent mechanism when depolorized with high extracellular K+ concentration. In this study, we show that certain neurons in the newborn retina already possess a specific mechanism for GABA uptake. The positions and numbers of these cells in the developing retina suggest that they will become GABA-ergic neurons in the adult retina. These putative GABA-ergic neurons are, however, probably immature at birth because newborn retinas contain only low levels of GABA and GAD. Additionally, there is relatively little K+-stimulated, Ca++-dependent release of (3H)-GABA from the newborn retinas. GABA concentrations and GAD activities in developing retinas increase steadily postnatally, reaching about 80% of the adult levels by day 9. The activities of the GABA-degrading enzyme, GABA-glutamate transaminase (GABA-T, EC 2.6.1.19), follow a similar pattern of maturation during retinal development. K+ stimulated GABA release, however, remains low until about day 6, and then increases dramatically from 20% to 85% of the adult level over the next 3 days. Taken together, our results indicate that in the rabbit retina, the commitment by certain neurons to use GABA as the transmitter is made prenatally. These neurons are immature at birth but are biochemically, physiologically, and probably functionally mature by about 9 days after birth.

The effects of guanyl nucleotides on the binding of [3H]flunitrazepam to rat hippocampal synaptic membranes were studied. In equilibrium binding studies, gamma-amino-n-butyric acid (GABA) increased and GTP decreased the binding affinity of [3H]flunitrazepam; GTP also caused a decrease in binding capacity. The effect, however, is variable. In studies of the dissociation kinetics of [3H]flunitrazepam using diazepam and the antagonist Ro 15-1788 as the displacers, there was evidence of two dissociation rate constants. GTP increased both the fast- and slow-dissociation rate constants and increased the ratio of the slow-dissociation binding state. The effect of GTP was mimicked by its nonhydrolyzable analogue 5'-guanylylimidodiphosphate but not by ATP and occurred when diazepam, but not when Ro 15-1788, was used as the displacer. GABA antagonized the effect of GTP on the dissociation of [3H]flunitrazepam. The nature of the benzodiazepine receptor, its actions, and the possible role of cyclic AMP as a second messenger are discussed.

Certain neurons in the adult rabbit retina possess a high-affinity uptake mechanism for glycine and release it in response to elevated K+ concentrations in the medium. Although the evidence is not yet complete, these properties, together with pharmacological studies, suggest that the glycine-accumulating neurons may be a subpopulation of amacrine cells and may use glycine as a neurotransmitter. In the present study, we have used the uptake and K+-stimulated release of glycine as physiological probes to follow the emergence and maturation of putative glycinergic neurons during postnatal development of the rabbit retina. We show that certain neurons in the newborn retina already possess a specific high-affinity mechanism for glycine uptake. The positions and density of these cells in the developing retina suggest that they will become glycine-accumulating neurons of the adult retina. Thus, similar to our earlier study on the development of GABA-ergic neurons in this retina, the commitment by certain retinal neurons to be glycinergic, if indeed these cells use glycine as the transmitter, is made prenatally. These putative glycinergic neurons are, however, probably immature at birth, because they do not release the accumulated glycine in response to high K+ concentrations in the medium. In fact, there is practically no K+-stimulated release of preloaded glycine from the retina until about 7 days after birth, after which the release increases drastically to about 65% of the adult level on day 10 and 80% on day 12. Assuming that this release originates synaptically, our finding suggests that the putative glycinergic neurons may be functionally mature by 10-12 days after birth. Additionally, our results show that during development of the rabbit retina, the mechanism for high-affinity glycine uptake emerges and matures much earlier than the mechanism for K+-stimulated glycine release.

Bronchial cancer is a disease of high and increasing annual incidence in Hong Kong, especially in women, whose age-specific death rates from this cause are amongst the highest in the world. A case-control study of the relationship of bronchial cancer with smoking was carried out during 1976--77, taking particular note of the histological type of the tumour. Two hundred and eight male and 189 female patients were interviewed, covering about half the total number of cases of bronchial cancer registered as dead from the disease in Hong Kong during the period of the survey. The association with smoking was more evident in males than in females, and in squamous and small-cell types, as a group, than in adenocarcinoma. Forty-four per cent of the women with bronchial cancer were non-smokers, their predominant tumour being adenocarcinoma, and in them on association could be detected with place of residence or occupation. There was no strong evidence of an association with the use of kerosene or gas for cooking; 23 did not use kerosene. The cause of the cancer in these non-smoking women remains unknown.

We compared the outcome of 472 trauma patients who required ambulance attention and who received prehospital advanced life support (ALS) with another similar 589 patients who received only basic life support (BLS). Nontrapped, critically injured ALS patients were treated for an average of 13 minutes at the scene of injury, compared with 17 minutes for BLS cases (P less than .05). Seventeen of 37 ALS deaths (36%) occurred within 24 hours of injury, compared with 24 of 33 BLS fatalities (73%) (P less than .05). However, the overall case fatality rate was similar in the two groups, and regression analyses did not demonstrate an impact of ALS care on mortality. ALS resuscitation did not reduce the duration of hospital or intensive care unit stay, or the incidence of disability after head injury. However, the incidence of respiratory failure in the critically injured patients was 5% (ALS) and 19% (BLS) (P less than .025). ALS care appeared to influence patient outcome during the first 24 hours after injury, but had little impact on the later clinical course. Our sample size was too small to rule out any effect of ALS on in-hospital mortality. However, the improved 24-hour survival associated with ALS care suggests some benefit of prehospital resuscitation in major trauma.

Release of [(3)H]noradrenaline from rat hippocampal synaptosomes was triggered by pulses of 25 mM K(+), 5 ?M veratridine or superfusion with the Ca(2+) ionophore A23187. GABA with bicuculline or chlordiazepoxide depressed the release of [(3)H]noradrenaline evoked by depolarisation but not by the Ca(2+) ionophore. 8 Br-cAMP with [Ca(2+)](0) 0.3 mM had no effect on spontaneous or K(+)-evoked release of [(3)H]noradrenaline and completely blocked the effect of chlordiazepoxide and GABA with bicuculline. With [Ca(2+)](0) 1 mM 8 Br-cAMP enhanced spontaneous and K(+)-evoked release of [(3)H]noradrenaline, and reversed the depression caused by GABA with bicuculline. GABA alone evoked Ca(2+)-dependent release of [(3)H]noradrenaline which was sensitive to [Cl(?)](0). The results suggest that the GABA(A)-receptor mediated release of [(3)H]noradrenaline is due to depolarisation resulting from increased Cl(?) conductance whereas the depression of depolarisation-dependent release of [(3)H]noradrenaline by GABA(B) or benzodiazepine receptors is mediated by a cAMP-dependent decrease in the voltage-dependent Ca(2+) conductance.