Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 53
Filter
2.
J Bone Joint Surg Am ; 105(12): 924-932, 2023 06 21.
Article in English | MEDLINE | ID: mdl-37220180

ABSTRACT

BACKGROUND: Total knee arthroplasty (TKA) is a cost-effective procedure, but it is also associated with substantial postoperative pain. The present study aimed to compare pain relief and functional recovery after TKA among groups that received intravenous corticosteroids, periarticular corticosteroids, or a combination of both. METHODS: This randomized, double-blinded clinical trial in a local institution in Hong Kong recruited 178 patients who underwent primary unilateral TKA. Six of these patients were excluded because of changes in surgical technique; 4, because of their hepatitis B status; 2, because of a history of peptic ulcer; and 2, because they declined to participate in the study. Patients were randomized 1:1:1:1 to receive placebo (P), intravenous corticosteroids (IVS), periarticular corticosteroids (PAS), or a combination of intravenous and periarticular corticosteroids (IVSPAS). RESULTS: The pain scores at rest were significantly lower in the IVSPAS group than in the P group over the first 48 hours (p = 0.034) and 72 hours (p = 0.043) postoperatively. The pain scores during movement were also significantly lower in the IVS and IVSPAS groups than in the P group over the first 24, 48, and 72 hours (p ≤ 0.023 for all). The flexion range of the operatively treated knee was significantly better in the IVSPAS group than in the P group on postoperative day 3 (p = 0.027). Quadriceps power was also greater in the IVSPAS group than in the P group on postoperative days 2 (p = 0.005) and 3 (p = 0.007). Patients in the IVSPAS group were able to walk significantly further than patients in the P group in the first 3 postoperative days (p ≤ 0.003). Patients in the IVSPAS group also had a higher score on the Elderly Mobility Scale than those in the P group (p = 0.036). CONCLUSIONS: IVS and IVSPAS yielded similar pain relief, but IVSPAS yielded a larger number of rehabilitation parameters that were significantly better than those in the P group. This study provides new insights into pain management and postoperative rehabilitation following TKA. LEVEL OF EVIDENCE: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.


Subject(s)
Arthroplasty, Replacement, Knee , Pain Management , Humans , Aged , Pain Management/methods , Arthroplasty, Replacement, Knee/adverse effects , Treatment Outcome , Pain, Postoperative/drug therapy , Pain, Postoperative/etiology , Adrenal Cortex Hormones , Anesthetics, Local , Double-Blind Method
3.
Neural Netw ; 161: 154-164, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36745940

ABSTRACT

We devise a new type of feedforward neural network. It is equivariant with respect to the unitary group U(n). The input and output can be vectors in ℂn with arbitrary dimension n. No convolution layer is required in our implementation. We avoid errors due to truncated higher order terms in Fourier-like transformation. The implementation of each layer can be done efficiently using simple calculations. As a proof of concept, we have given empirical results on the prediction of the dynamics of atomic motion to demonstrate the practicality of our approach.


Subject(s)
Neural Networks, Computer , Motion
4.
J Phys Chem C Nanomater Interfaces ; 126(32): 13640-13648, 2022 Aug 18.
Article in English | MEDLINE | ID: mdl-36017360

ABSTRACT

Compositional mixing provides the means to maintain the structural stability of a hybrid organic-inorganic perovskite for efficient and robust photovoltaic applications. Here we present a theoretical, first-principles study of the electronic and energetic properties of the solid solution (CH(NH2)2) x (CH3NH3)1-x PbBr y I1-y , the mixing of two organic molecules with various orientations, formamidinium and methylammonium, and two halides, bromide and iodide. Our results show the variation in the band gap as a function of composition (x and y) provides several candidates that exceed the 27.5% Schockley-Queisser efficiency. The variation in the composition of hybrid perovskite shows specific regions where either the hexagonal or cubic phase dominates. We discuss the balance between the band gap and phase stability and indicate regions where the phase transition temperature between cubic and hexagonal phases is far from room temperature, indicating that these compositions are more robust at room temperature against phase transitions.

5.
Clin Oncol (R Coll Radiol) ; 32(10): 639-646, 2020 10.
Article in English | MEDLINE | ID: mdl-32732110

ABSTRACT

The association of breast implants and anaplastic large cell lymphoma (BIA-ALCL) was first described in 1997. Such an association has aroused public health concerns on breast implant safety. A systematic review was carried out with a pooled analysis of data. In total, 674 non-duplicate articles were retrieved; 77 articles were included for data extraction; 395 patients were identified for analysis. The median age at the time of diagnosis was 52 years. Implant texture was described in 201 (50.9%) patients; all 201 patients had a textured implant. The median time from the last implant insertion to diagnosis was 7.5 years. Most patients presented with seroma (67.1%, n = 265), 20.5% of patients presented with breast mass (n = 81). Patients with a breast mass at presentation, lymphadenopathy and those without seroma had more disseminated disease (P < 0.001). 73.2% of patients (n = 289) opted for primary surgery, among which 68.6% (n = 271) received removal of the implant, 61% (n = 241) received capsulectomy and 2% (n = 8) received mastectomy. Of note, 5.3% (n = 21) had reinsertion of an implant after primary surgery. Non-surgical modalities included chemotherapy, radiotherapy and haematopoietic stem cell transplant. The median follow-up interval was 2 years (range 0-14.5 years). Seventeen patients (4.3%) had recurrence of BIA-ALCL and 195 patients (49.4%) did not. The median duration to first recurrence was 1 year (range 1-3 years). Long-term clinical outcome was not reported in 183 patients. BIA-ALCL is an indolent disease that presents with seroma after implant insertion. A high index of suspicion is needed for early diagnosis and treatment.


Subject(s)
Breast Implants/adverse effects , Breast Neoplasms/surgery , Lymphoma, Large-Cell, Anaplastic/etiology , Breast Neoplasms/pathology , Cohort Studies , Female , Humans , Lymphoma, Large-Cell, Anaplastic/pathology , Prognosis
6.
Nanoscale ; 12(39): 20189-20201, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-32677627

ABSTRACT

For potential applications in ferroelectric switching and piezoelectric nano-generator devices, the promising ferroelectric properties of two dimensional (2D) layered In2Se3 attracted much attention. In the present study, 2D In2Se3 flakes down to monolayers are grown by the chemical vapor deposition (CVD) technique on a mica substrate with their structural, optical and ferroelectric properties being studied. The effect of growth parameters (time of growth and Ar flow rate) on the shape and size of the deposited flakes was studied. The optical microscopy study revealed that the flake changed from a circular shape to a sharp face triangle as the Ar flow rate and growth time increased. Raman spectroscopy and high-resolution scanning transmission electron microscopy (HR-STEM) studies revealed that the flakes were of α and ß phases, each of which has a hexagonal crystal structure. Strong second harmonic generation (SHG) was observed from α-In2Se3, demonstrating its non-centrosymmetric structure. The piezo-force microscopic (PFM) study showed the presence of out of plane (OOP) ferroelectricity with no in plane (IP) ferroelectricity in CVD grown α-In2Se3 indicating its vertically confined piezoresponse, which was tuned by the applied electric bias and the flake thickness. The present result of shape-controlled growth of In2Se3 with OOP ferroelectricity would open new pathways in the field of 2D ferroelectric switching devices.

9.
Hum Reprod ; 30(2): 364-72, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25480921

ABSTRACT

STUDY QUESTION: What are the levels of awareness regarding female fertility and the intentions and attitudes towards parenthood among Chinese university students in Hong Kong compared with their counterparts in the West? SUMMARY ANSWER: Chinese university students in Hong Kong were similarly over-optimistic about the age-related fertility decline, although they were less inclined to have children and undergo fertility treatment compared with their Western counterparts. WHAT IS KNOWN ALREADY: Past studies of highly educated young adults in Europe and the USA have found that they are not sufficiently aware of the age-related decline in female fertility, and falsely believe that advanced reproductive treatments such as IVF will overcome fertility problems associated with age. Little is known about the perceptions of Chinese students in Hong Kong, a modernized Chinese city where the fertility rate is among the lowest in the world. STUDY DESIGN, SIZE, DURATION: An online cross-sectional survey of Chinese university students in Hong Kong was conducted in 2013. Results were compared with two similar studies in Sweden and the USA. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 367 university students in Hong Kong (275 female, 92 male; mean age 23) responded to an e-mail invitation to participate in an online survey. Intentions and attitudes towards parenthood and awareness regarding female fertility were assessed using the Swedish Fertility Awareness Questionnaire. MAIN RESULTS AND THE ROLE OF CHANCE: Like their Western counterparts, a large proportion of Chinese university students underestimated the age-related fertility decline (92%) and overestimated the fertility treatment success rate (66%). However, they were less inclined to have children, were more aware of and less concerned with infertility and were less motivated to seek solutions in the event of a fertility problem. These comparisons were significant at P < 0.05. LIMITATIONS, REASONS FOR CAUTION: Self-selection bias was inevitable in the questionnaire survey, and the anonymous nature of the survey did not permit the collection of characteristics of non-responders. International comparisons warrant caution because the Hong Kong sample was older than the US sample (mean age 20), but not older than the Sweden sample (mean age 24). WIDER IMPLICATION OF FINDINGS: While this study was consistent with past Western studies on the lack of fertility awareness among highly educated young people, the findings reveal significant cultural differences in family planning and responses to infertility between Asia and the West.


Subject(s)
Aging , Fertility , Health Knowledge, Attitudes, Practice , Parenting , Reproductive Behavior , Reproductive Health/education , Urban Health , Adult , Age of Onset , China/epidemiology , Cross-Sectional Studies , Female , Health Knowledge, Attitudes, Practice/ethnology , Humans , Infertility, Female/epidemiology , Infertility, Female/ethnology , Infertility, Female/etiology , Infertility, Female/therapy , Internet , Male , Parenting/ethnology , Parenting/psychology , Reproductive Behavior/ethnology , Reproductive Behavior/psychology , Reproductive Health/ethnology , Reproductive Techniques, Assisted/adverse effects , Students , Universities , Urban Health/ethnology , Young Adult
10.
Int J Rheum Dis ; 16(5): 500-8, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24164836

ABSTRACT

Low back pain is one of commonest problems prompting a visit to the family physician. Up to 5% of patients with chronic low back pain in the primary care setting are diagnosed as having spondyloarthritis, which includes the prototype disease ankylosing spondylitis. Making a diagnosis of ankylosing spondylitis is often delayed for years, leading to significant pain, impairment of quality of life, disability and productivity loss. A recent breakthrough in the treatment of spondyloarthritis is the anti-tumor necrosis factor-alpha biologics, which lead to rapid relief of pain and inflammation, and improvement in all clinical parameters of the disease. Patients with early spondyloarthritis often respond better than those with late established disease. With proper recognition of inflammatory back pain, and the use of magnetic resonance imaging, spondyloarthritis can now be diagnosed much earlier before features are evident on plain radiographs. Referral to the rheumatologist based on onset of back pain (> 3 months) before the age of 45 years, and an inflammatory nature of the pain, or the presence of human leukocyte antigen-B27, or sacroiliitis by imaging, have been confirmed in multi-center international studies to be a pragmatic approach to enable early diagnosis of spondyloarthritis. This referral strategy has recently been adopted by the Hong Kong Society of Rheumatology for primary care physicians and non-rheumatology specialists.


Subject(s)
Chronic Pain/diagnosis , Low Back Pain/diagnosis , Primary Health Care/standards , Referral and Consultation/standards , Rheumatology/standards , Societies, Medical/standards , Spondylitis, Ankylosing/diagnosis , Adult , Age of Onset , Chronic Pain/epidemiology , Chronic Pain/therapy , Consensus , Diagnostic Imaging/standards , Early Diagnosis , Hong Kong , Humans , Incidence , Low Back Pain/epidemiology , Low Back Pain/therapy , Middle Aged , Pain Measurement/standards , Predictive Value of Tests , Prognosis , Risk Factors , Severity of Illness Index , Spondylitis, Ankylosing/epidemiology , Spondylitis, Ankylosing/therapy
11.
Oncogene ; 31(18): 2298-308, 2012 May 03.
Article in English | MEDLINE | ID: mdl-21909138

ABSTRACT

DNA methyltransferase 3B (DNMT3B) mediates gene silencing via epigenetic mechanisms during hepatocellular carcinoma (HCC) progression. We aimed to identify novel targets of DNMT3B and their potential regulatory mechanisms in HCC. Metastasis suppressor 1 (MTSS1) was one of the DNMT3B targets and selected for further study. DNMT3B overexpression was detected in 81.25% of clinical HCC specimens and was negatively associated with MTSS1 in HCC cells and clinical samples. The underlying mechanism by which DNMT3B silences MTSS1 was studied using a combination of methylation-specific polymerase chain reaction (PCR) and bisulfite genome sequencing, chromatin immunoprecipitation-PCR and luciferase reporter assays. We found that the MTSS1 promoter region was sparsely methylated, and the methylation inhibitors failed to abolish DNMT3B-mediated MTSS1 silencing. DNMT3B protein bound directly to the 5'-flanking region (-865/-645) of the MTSS1 gene to inhibit its transcription. The functional role of MTSS1 was investigated using in vitro and in vivo tumorigenicity assays. As a result, MTSS1 exerted tumor suppressor effects and arrested cells in the G2/M phase, but not the G1/S phase of the cell cycle when it was depleted or overexpressed in HCC cells. Taken together, MTSS1, a novel target of DNMT3B, is repressed by DNMT3B via a DNA methylation-independent mechanism. MTSS1 was further characterized as a novel tumor suppressor gene in HCC. These findings highlight how DNMT3B regulates MTSS1, and such data may be useful for the development of new treatment options for HCC.


Subject(s)
Carcinoma, Hepatocellular , DNA (Cytosine-5-)-Methyltransferases/metabolism , Liver Neoplasms , Microfilament Proteins/metabolism , Neoplasm Proteins/metabolism , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Cycle Checkpoints/genetics , Cell Line, Tumor , DNA Methylation , DNA, Neoplasm/metabolism , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Microfilament Proteins/genetics , Neoplasm Proteins/genetics , Promoter Regions, Genetic , DNA Methyltransferase 3B
12.
Curr Cancer Drug Targets ; 11(3): 296-306, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21247384

ABSTRACT

Next to water, tea is the most popular beverage in the world. The most abundant and active compound in green tea is (-)-epigallocatechin-3-gallate (EGCG), which is extensively studied for its cancer-preventive and anti-cancer activities as well as its cellular targets. One potential molecular target of EGCG is the proteasome. While molecular docking and structure-activity relationship (SAR) analysis suggests that the ester carbon of EGCG is important for mediating its proteasome-inhibitory activity, EGCG is very unstable under physiological conditions. Therefore, a series of analogs were synthesized aiming to improve stability and bioavailability of EGCG. Among them, peracetate-protected or the prodrug of EGCG was found to have increased bioavailability, stability, and proteasome-inhibitory activities against various human cancer cells and tumors compared to EGCG, suggesting its potential use for cancer prevention and treatment. Epidemiological studies have indicated that green tea consumption is associated with the reduced risk of cancers, especially associated with the reduced risk of late stage of cancers. This risk reduction may be attributed not only to proteasome inhibition, but also to numerous other intracellular molecules targeted by EGCG that are involved in cell cycle regulation, apoptosis, angiogenesis, and metastasis.


Subject(s)
Antineoplastic Agents/therapeutic use , Flavonoids/therapeutic use , Neoplasms/prevention & control , Phenols/therapeutic use , Protease Inhibitors/therapeutic use , Proteasome Inhibitors , Tea , Animals , Humans , Neoplasms/metabolism , Polyphenols , Proteasome Endopeptidase Complex/metabolism
13.
Inflammopharmacology ; 16(5): 248-52, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18815735

ABSTRACT

The health benefits of green tea and its main constituent (-)-epigallocatechin gallate [(-)-EGCG] have been widely supported by results from epidemiological, cell culture, animal and clinical studies. On the other hand, there are a number of issues, such as stability, bioavailability and metabolic transformations under physiological conditions, facing the development of green tea polyphenols into therapeutic agents. We previously reported that the synthetic peracetate of (-)-EGCG has improved stability and better bioavailability than (-)-EGCG itself and can act as pro-drug under both in vitro and in vivo conditions. Analogs of catechins have been synthesized and their structure activity relationship provides an understanding to the mechanism of proteasome inhibition. Metabolic methylation of catechins leading to methylated (-)-EGCG may alter the biological activities of these compounds.


Subject(s)
Catechin/analogs & derivatives , Tea/chemistry , Biological Availability , Biotransformation , Catechin/chemical synthesis , Catechin/isolation & purification , Catechin/pharmacokinetics , Catechin/therapeutic use , Humans , Structure-Activity Relationship
14.
Inflammopharmacology ; 16(5): 208-12, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18815743

ABSTRACT

The cancer-preventive effects of green tea and its main constituent (-)-epigallocatechin gallate [(-)-EGCG] are widely supported by results from epidemiological, cell culture, animal and clinical studies although the molecular target has not been well defined. We previously reported that ester bond-containing tea polyphenols, e. g. (-)-EGCG, and their synthetic analogs potently and specifically inhibited the proteasomal activity. Subsequently, we further demonstrated that methylation on green tea polyphenols under physiological conditions decreased their proteasome-inhibitory activity, contributing to decreased cancer-preventive effects of tea consumption. Since (-)-EGCG is unstable under physiological conditions, we also developed the peracetate-protected or prodrug form of (-)-EGCG, Pro-EGCG (1), and shown that Pro-EGCG (1) increases the bioavailability, stability, and proteasome-inhibitory and anticancer activities of (-)-EGCG in human breast cancer cells and xenografts, suggesting its potential use for cancer prevention and treatment.


Subject(s)
Anticarcinogenic Agents/pharmacology , Catechin/analogs & derivatives , Proteasome Inhibitors , Tea , Catechin/pharmacology , Methylation , Ubiquitin/metabolism
15.
Histol Histopathol ; 23(4): 487-96, 2008 04.
Article in English | MEDLINE | ID: mdl-18228206

ABSTRACT

Tea is the most popular beverage in the world, second only to water. Tea contains an infusion of the leaves from the Camellia sinensis plant rich in polyphenolic compounds known as catechins, the most abundant of which is (-)-EGCG. Although tea has been consumed for centuries, it has only recently been studied extensively as a health-promoting beverage that may act to prevent a number of chronic diseases and cancers. The results of several investigations indicate that green tea consumption may be of modest benefit in reducing the plasma concentration of cholesterol and preventing atherosclerosis. Additionally, the cancer-preventive effects of green tea are widely supported by results from epidemiological, cell culture, animal and clinical studies. In vitro cell culture studies show that tea polyphenols potently induce apoptotic cell death and cell cycle arrest in tumor cells but not in their normal cell counterparts. Green tea polyphenols were shown to affect several biological pathways, including growth factor-mediated pathway, the mitogen-activated protein (MAP) kinase-dependent pathway, and ubiquitin/proteasome degradation pathways. Various animal studies have revealed that treatment with green tea inhibits tumor incidence and multiplicity in different organ sites such as skin, lung, liver, stomach, mammary gland and colon. Recently, phase I and II clinical trials have been conducted to explore the anticancer effects of green tea in humans. A major challenge of cancer prevention is to integrate new molecular findings into clinical practice. Therefore, identification of more molecular targets and biomarkers for tea polyphenols is essential for improving the design of green tea trials and will greatly assist in a better understanding of the mechanisms underlying its anti-cancer activity.


Subject(s)
Anticarcinogenic Agents/pharmacology , Flavonoids/pharmacology , Neoplasms/prevention & control , Phenols/pharmacology , Tea , Animals , Apoptosis/drug effects , Clinical Trials, Phase I as Topic , Clinical Trials, Phase II as Topic , Flavonoids/chemistry , Flavonoids/therapeutic use , Humans , MAP Kinase Signaling System , Molecular Structure , Neoplasms/drug therapy , Neoplasms/epidemiology , Neoplasms/metabolism , Neoplasms/pathology , Phenols/chemistry , Phenols/therapeutic use , Polyphenols , Proteasome Endopeptidase Complex/metabolism , Signal Transduction , Ubiquitin/metabolism
16.
Australas Phys Eng Sci Med ; 29(2): 216-28, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16845928

ABSTRACT

Increased inter-equipment connectivity coupled with advances in Web technology allows ever escalating amounts of physiological data to be produced, far too much to be displayed adequately on a single computer screen. The consequence is that large quantities of insignificant data will be transmitted and reviewed. This carries an increased risk of overlooking vitally important transients. This paper describes a technique to provide an integrated solution based on a single algorithm for the efficient analysis, compression and remote display of long-term physiological signals with infrequent short duration, yet vital events, to effect a reduction in data transmission and display cluttering and to facilitate reliable data interpretation. The algorithm analyses data at the server end and flags significant events. It produces a compressed version of the signal at a lower resolution that can be satisfactorily viewed in a single screen width. This reduced set of data is initially transmitted together with a set of 'flags' indicating where significant events occur. Subsequent transmissions need only involve transmission of flagged data segments of interest at the required resolution. Efficient processing and code protection with decomposition alone is novel. The fixed transmission length method ensures clutter-less display, irrespective of the data length. The flagging of annotated events in arterial oxygen saturation, electroencephalogram and electrocardiogram illustrates the generic property of the algorithm. Data reduction of 87% to 99% and improved displays are demonstrated.


Subject(s)
Algorithms , Computer Graphics , Data Compression/methods , Data Display , Information Storage and Retrieval/methods , Monitoring, Physiologic/methods , Telemedicine/methods , User-Computer Interface , Data Interpretation, Statistical , Database Management Systems , Databases, Factual , Reproducibility of Results , Sensitivity and Specificity , Signal Processing, Computer-Assisted
17.
Chin J Dig Dis ; 7(1): 24-32, 2006.
Article in English | MEDLINE | ID: mdl-16412034

ABSTRACT

BACKGROUND: The is currently a heavy burden on endoscopy services worldwide and although guidelines for the appropriate use of esophagogastroduodenoscopy (EGD) have been well studied, there are few such studies with respect to colonoscopy and none for the Asia-Pacific region. This study aimed, firstly, to determine the 'appropriateness of colonoscopy' for procedures performed in the endoscopy unit of a large Asian hospital using the American Society of Gastrointestinal Endoscopy (ASGE) 2000 guidelines, and secondly, to determine predictive factors including 'appropriateness of colonoscopy' for positive findings and colorectal cancer (CRC). METHODS: A prospective cross-sectional study was carried out on consecutive colonoscopies performed in the University of Malaya Medical Center. The unit has an open-access endoscopy policy for doctors who work in the hospital. Referrals were from endoscopists (gastroenterologists and surgeon-endoscopists), primary care physicians and other specialists. The indication of a procedure referral was recorded and judged 'appropriate' or 'inappropriate' using the ASGE criteria. The colonoscopic findings were recorded and classified as positive (endoscopies showing any pathology that had direct therapeutic or prognostic consequences) or negative findings (endoscopies showing no pathology or minor pathologies). Predictive factors for positive findings and CRC were determined using multivariate analysis. RESULTS: Of 380 patients referred for colonoscopy, 220 (57.9%) were classified as appropriate according to the ASGE guidelines, and 49 (12.9%) as inappropriate. The remaining 111 patients (29.2%) presented with complaints and conditions that could not be categorized. The rate of appropriate referral was similar for all three categories of physician (endoscopists: 59.8%, primary care physicians: 48.1%, others: 51.1%). When referrals by endoscopists were substratified according to gastroenterologists and surgeon-endoscopists, the rate of appropriate referral among gastroenterologists (78.4%) was significantly higher than that of surgeon-endoscopists (56.1%) (P = 0.049), primary care physicians (P = 0.013) and 'others' (P = 0.009). The most common appropriate indications were unexplained Rectalbleeding (79 cases, 20.8%) followed by CRC surveillance (45 cases, 11.8%). The most common inappropriate indication was inappropriately timed colonic cancer surveillance (32 cases, 8.4%). Chronic constipation in 36 cases (9.5%) was the most common 'unlisted' indication. A positive colonoscopic finding was detected in 131 (34.5%) examinations and CRC was found in 36 patients (9.5%). Appropriateness of indication was not a predictive factor for positive findings or CRC and there was no difference in the proportion of cases with positive findings or CRC in the three 'appropriateness categories'. Multivariate analysis revealed that only Rectalbleeding and smoking were significant independent positive predictive factors for positive findings and CRC. CONCLUSION: The appropriateness of colonoscopy was not high among the different sources of referrals except for the subgroup of 'gastroenterologist'. Furthermore, the rates of positive findings and CRC among the cases with appropriate, inappropriate and unlisted indications did not differ. The ASGE guidelines will need to be modified for Asia to be of practical use.


Subject(s)
Colonoscopy/statistics & numerical data , Colorectal Neoplasms/diagnosis , Practice Guidelines as Topic , Utilization Review , Adult , Aged , Aged, 80 and over , Colorectal Neoplasms/epidemiology , Cross-Sectional Studies , Female , Hospitals, University/statistics & numerical data , Humans , Malaysia/epidemiology , Male , Middle Aged , Prospective Studies , Risk Factors , Unnecessary Procedures
18.
J Org Chem ; 66(10): 3467-73, 2001 May 18.
Article in English | MEDLINE | ID: mdl-11348131

ABSTRACT

Reaction of sulfonimines having proximal chelating groups with crotyl bromide and indium in aqueous media gave alpha-crotylation products stereoselectively with syn-selectivity.

19.
Org Lett ; 3(5): 739-41, 2001 Mar 08.
Article in English | MEDLINE | ID: mdl-11259050

ABSTRACT

[reaction: see text]. Enantioselective synthesis of epigallocatechin-3-gallate (EGCG, 3b), the active polyphenol component from green tea, has been achieved by using a stereospecific cyclization of the Sharpless asymmetric dihydroxylation product 7c as the key step.


Subject(s)
Antineoplastic Agents, Phytogenic/chemical synthesis , Catechin/chemical synthesis , Tea/chemistry , Catechin/analogs & derivatives , Oxidation-Reduction , Stereoisomerism
20.
J Org Chem ; 65(25): 8589-94, 2000 Dec 15.
Article in English | MEDLINE | ID: mdl-11112579

ABSTRACT

Sulfonimines derived from aryl and nonenolizable aliphatic aldehydes can be effectively allylated to the corresponding homoallylic sulfonamides with allylic bromides promoted by indium or zinc. The solvent used can be water, THF, or a mixed aqueous THF solvent. The regioselectivity and stereoselectivity of the reaction were studied.

SELECTION OF CITATIONS
SEARCH DETAIL
...