: Replication of single stranded M 13 DNA by the calf thymus DNApolymerase alpha:primase complex ... more : Replication of single stranded M 13 DNA by the calf thymus DNApolymerase alpha:primase complex and herpes simplex virus type 1(HSV-1) DNA polymerase was examined by electron microscopy. The replicative intermediates isolated from the reaction were spread for electron microscopy in the presence of E. Coli single stranded binding (SSB) protein and ethidium bromide. The electron microscopic analysis of the replicative intermediates from the calf thymus DNA primase primed M13 DNA replication showed an average of 2.5 primers per M13 DNA circle. The measurement of the double stranded length from individual replicative intermediates by electron microscopy was within the accuracy of 10% standard deviation. The product length distribution obtained from the HSV-1 DNA polymerase catalyzed replication of M13 DNA primed with a specific pentadecamer and in the presence of E. Coli SSB protein showed a near Poisson distribution. Replication of the same primer-template system or DNA primase primed...
This systematic review aimed to evaluate the clinical performance of core-carrier obturation in e... more This systematic review aimed to evaluate the clinical performance of core-carrier obturation in endodontic treatment. Keywords of "(core carrier OR Thermafil) OR (cold lateral condensation OR lateral condensation) OR (warm vertical condensation OR vertical condensation) AND (obturation OR root canal filling) AND clinical study" were searched for all obtainable publications up to year 2017 in the databases of PubMed, ScienceDirect, EMBASE, Scopus and Web of Science. The success rate, short-term postoperative pain, overfilling and adaptation of core-carrier obturation from clinical studies were selected. Reviews, laboratory studies, animal studies and irrelevant reports were excluded. 1349 relevant articles were identified with 149 duplicated articles removed and 1173 irrelevant articles were excluded after screening. The titles and abstracts of the 19 identified articles were screened in the systematic review. The full texts of remaining articles were retrieved with data ex...
This study investigated dental caries status and its associated factors among 5-year-old children... more This study investigated dental caries status and its associated factors among 5-year-old children in Hong Kong. This cross-sectional survey was conducted in 2016. It comprised a questionnaire survey and a clinical examination. Kindergarten children aged 5 were recruited using a multistage sampling method. Parents of the participating children were asked about their children's demographic information, sugary snacking behaviours, and oral health-related behaviours and about their own oral health knowledge. One trained dentist performed oral examinations on the children. Caries experience was measured using the dmft index. The relationships between the dmft scores and background information, sugary snacking behaviours, oral health-related behaviours and parental dental knowledge were studied using a zero-inflated negative binomial (ZINB) regression analysis. A total of 570 children were invited to participate, and 501 completed the oral examination (response rate: 88%). The prevale...
Contamination during urine collection causes difficulty in diagnosing infantile urinary tract inf... more Contamination during urine collection causes difficulty in diagnosing infantile urinary tract infection (UTI). Though considered a gold-standard, suprapubic aspiration is traumatic and not always successful. Catheterization and clean void technique were often preferred but their relative usefulness has not been compared. To compare the culture results of clean void urine (CVU) and catheter urine (CathU) from children below 2-years old known to have no UTI. We tested whether the false-positive rates of CVU were significantly different from that of CathU. Paired CVU and CathU samples were collected from asymptomatic children admitted for micturiting cystourethrogram, and tested for leucocytes and nitrite, and bacterial culture using standard laboratory methods. Culture results for 98 children (82 boys, 16 girls; aged 6 +/- 4.3 months) were analysed. Analysis by presence/absence of growths showed good agreement between CVU and CathU for boys (Kappa 0.42) but poor for girls (Kappa 0.18)...
Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine, 2008
To report a recent clustering of chilblain cases in Hong Kong. Case series. A regional hospital a... more To report a recent clustering of chilblain cases in Hong Kong. Case series. A regional hospital and a social hygiene clinic in the New Territories West, Hong Kong. Patients with a clinical diagnosis of chilblains in February 2008. Eleven patients with chilblains were identified; seven (64%) gave an antecedent history of prolonged exposure to cold. They all presented with erythematous or dusky erythematous skin lesions affecting the distal extremities, especially fingers and toes. Laboratory tests revealed elevated antinuclear antibodies titres in two, positive rheumatoid factor in two, presence of cold agglutinins in one, and a raised anti-DNA titre (>300 IU/mL) in one. Skin biopsies were performed in six patients, four of them showed typical histopathological features of chilblains. In the patient with systemic lupus erythematosus, features of vasculitis were suspected, and in the one with pre-existing juvenile rheumatoid arthritis, there were features of livedo vasculitis. In 1...
To study patients' satisfaction and prevalence of complications in surgical extraction of imp... more To study patients' satisfaction and prevalence of complications in surgical extraction of impacted third molar by senior dentists and recently graduated dentists in a university dental clinic. Patients who had impacted third molar extraction in a university dental clinic by two associate dentists who had <2 years of experience and two senior dentists who had >15 years of experience were evaluated in this study. Patients' age, sex, history of pericoronitis, tooth extracted, and radiographic assessment of the impacted tooth were recorded. Immediately after suture removal, the patients were invited to indicate their satisfaction on a Likert scale of 1-5. A total of 546 patients received extraction, and 251 patients were operated by associate dentists. Patient satisfaction was higher among those who had noncomplicated surgery (P=0.007), short treatment time (P<0.001), and had no postsurgical emergency appointments (P<0.001). The prevalence of seeking postsurgical eme...
Taq DNA polymerase, Sequenase, and the large fragment of E.coli polymerase I effectively utilize ... more Taq DNA polymerase, Sequenase, and the large fragment of E.coli polymerase I effectively utilize N4-methyl-2&#39;-deoxycytidine 5&#39;-triphosphate (N4-methyl-dCTP) in the place of dCTP in dideoxynucleotide terminator sequencing reactions on single-stranded templates. When the resulting fragment mixtures are resolved on sequencing gels, they are found to be free of band compressions even in cases where such compressions remain unresolved by the substitution of 7-deaza-dGTP for dGTP. Sequencing reactions using N4-methyl-dCTP instead of dCTP are somewhat more prone to false stops than are sequencing reactions using 7-deaza-dGTP instead of dGTP; this difference is more pronounced when sequencing with Sequenase at 37 degrees C than when sequencing with Taq DNA polymerase at 72 degrees C. For the three polymerases investigated, replacement of dCTP by N4-methyl-dCTP does not fundamentally change the characteristic variations in band intensities seen in the C-lane. N4-methyl-dCTP can also be used for sequencing double-stranded DNA and for DNA amplification by the polymerase chain reaction.
We aimed to establish community-based normal reference values of 24-h ambulatory blood pressure m... more We aimed to establish community-based normal reference values of 24-h ambulatory blood pressure monitoring (ABPM) for Chinese children and adolescents. Furthermore, we investigated how excluding overweight children affects BP percentiles and compared them with German references. In this territory-wide cross-sectional prospective cohort study, 1445 Hong Kong Chinese children and adolescents aged 8-17 years with body height between 119 and 185 cm were recruited. Their ABPM assessment was performed using validated arm oscillometric recorders (A&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;D TM-2430) and complied with American Heart Association&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s recommendations. The reference tables were constructed using the LMS method to normalize skewed distribution of ABP data to sex and age or height. The ambulatory BP was higher among boys and the difference between boys and girls progressively widened with age. An increasing trend in daytime and night-time SBP and DBP with age and height was observed in both sexes. The age-specific and sex-specific 95th percentiles from nonoverweight children (n=1147; 79%) were lower than the whole cohort by up to 2.5 and 1 mmHg for SBP and DBP, respectively. In comparison, our overall and nonoverweight reference standards were generally higher than corresponding German references. The study provides ambulatory BP standards for Chinese children, with sex-related age-specific and height-specific percentiles. Further longitudinal studies are required for investigating its clinical utility in Chinese.
The antidiabetic intestinal L cell hormone glucagon-like peptide-1 (GLP-1) enhances glucose-depen... more The antidiabetic intestinal L cell hormone glucagon-like peptide-1 (GLP-1) enhances glucose-dependent insulin secretion and inhibits gastric emptying. GLP-1 secretion is stimulated by luminal oleic acid (OA), which crosses the cell membrane by an unknown mechanism. We hypothesized that L cell fatty acid transport proteins (FATPs) are essential for OA-induced GLP-1 release. Therefore, the murine GLUTag L cell model was used for immunoblotting, [3H]OA uptake assay, and GLP-1 secretion assay as determined by radioimmunoassay following treatment with OA ± phloretin, sulfo- N-succinimidyl oleate, or siRNA against FATP4. FATP4−/− and cluster-of-differentiation 36 (CD36)−/− mice received intraileal OA, and plasma GLP-1 was measured by sandwich immunoassay. GLUTag cells were found to express CD36, FATP1, FATP3, and FATP4. The cells demonstrated specific 3H[OA] uptake that was dose-dependently inhibited by 500 and 1,000 μM unlabeled OA ( P < 0.001). Cell viability was not altered by treat...
: Replication of single stranded M 13 DNA by the calf thymus DNApolymerase alpha:primase complex ... more : Replication of single stranded M 13 DNA by the calf thymus DNApolymerase alpha:primase complex and herpes simplex virus type 1(HSV-1) DNA polymerase was examined by electron microscopy. The replicative intermediates isolated from the reaction were spread for electron microscopy in the presence of E. Coli single stranded binding (SSB) protein and ethidium bromide. The electron microscopic analysis of the replicative intermediates from the calf thymus DNA primase primed M13 DNA replication showed an average of 2.5 primers per M13 DNA circle. The measurement of the double stranded length from individual replicative intermediates by electron microscopy was within the accuracy of 10% standard deviation. The product length distribution obtained from the HSV-1 DNA polymerase catalyzed replication of M13 DNA primed with a specific pentadecamer and in the presence of E. Coli SSB protein showed a near Poisson distribution. Replication of the same primer-template system or DNA primase primed...
This systematic review aimed to evaluate the clinical performance of core-carrier obturation in e... more This systematic review aimed to evaluate the clinical performance of core-carrier obturation in endodontic treatment. Keywords of "(core carrier OR Thermafil) OR (cold lateral condensation OR lateral condensation) OR (warm vertical condensation OR vertical condensation) AND (obturation OR root canal filling) AND clinical study" were searched for all obtainable publications up to year 2017 in the databases of PubMed, ScienceDirect, EMBASE, Scopus and Web of Science. The success rate, short-term postoperative pain, overfilling and adaptation of core-carrier obturation from clinical studies were selected. Reviews, laboratory studies, animal studies and irrelevant reports were excluded. 1349 relevant articles were identified with 149 duplicated articles removed and 1173 irrelevant articles were excluded after screening. The titles and abstracts of the 19 identified articles were screened in the systematic review. The full texts of remaining articles were retrieved with data ex...
This study investigated dental caries status and its associated factors among 5-year-old children... more This study investigated dental caries status and its associated factors among 5-year-old children in Hong Kong. This cross-sectional survey was conducted in 2016. It comprised a questionnaire survey and a clinical examination. Kindergarten children aged 5 were recruited using a multistage sampling method. Parents of the participating children were asked about their children's demographic information, sugary snacking behaviours, and oral health-related behaviours and about their own oral health knowledge. One trained dentist performed oral examinations on the children. Caries experience was measured using the dmft index. The relationships between the dmft scores and background information, sugary snacking behaviours, oral health-related behaviours and parental dental knowledge were studied using a zero-inflated negative binomial (ZINB) regression analysis. A total of 570 children were invited to participate, and 501 completed the oral examination (response rate: 88%). The prevale...
Contamination during urine collection causes difficulty in diagnosing infantile urinary tract inf... more Contamination during urine collection causes difficulty in diagnosing infantile urinary tract infection (UTI). Though considered a gold-standard, suprapubic aspiration is traumatic and not always successful. Catheterization and clean void technique were often preferred but their relative usefulness has not been compared. To compare the culture results of clean void urine (CVU) and catheter urine (CathU) from children below 2-years old known to have no UTI. We tested whether the false-positive rates of CVU were significantly different from that of CathU. Paired CVU and CathU samples were collected from asymptomatic children admitted for micturiting cystourethrogram, and tested for leucocytes and nitrite, and bacterial culture using standard laboratory methods. Culture results for 98 children (82 boys, 16 girls; aged 6 +/- 4.3 months) were analysed. Analysis by presence/absence of growths showed good agreement between CVU and CathU for boys (Kappa 0.42) but poor for girls (Kappa 0.18)...
Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine, 2008
To report a recent clustering of chilblain cases in Hong Kong. Case series. A regional hospital a... more To report a recent clustering of chilblain cases in Hong Kong. Case series. A regional hospital and a social hygiene clinic in the New Territories West, Hong Kong. Patients with a clinical diagnosis of chilblains in February 2008. Eleven patients with chilblains were identified; seven (64%) gave an antecedent history of prolonged exposure to cold. They all presented with erythematous or dusky erythematous skin lesions affecting the distal extremities, especially fingers and toes. Laboratory tests revealed elevated antinuclear antibodies titres in two, positive rheumatoid factor in two, presence of cold agglutinins in one, and a raised anti-DNA titre (>300 IU/mL) in one. Skin biopsies were performed in six patients, four of them showed typical histopathological features of chilblains. In the patient with systemic lupus erythematosus, features of vasculitis were suspected, and in the one with pre-existing juvenile rheumatoid arthritis, there were features of livedo vasculitis. In 1...
To study patients' satisfaction and prevalence of complications in surgical extraction of imp... more To study patients' satisfaction and prevalence of complications in surgical extraction of impacted third molar by senior dentists and recently graduated dentists in a university dental clinic. Patients who had impacted third molar extraction in a university dental clinic by two associate dentists who had <2 years of experience and two senior dentists who had >15 years of experience were evaluated in this study. Patients' age, sex, history of pericoronitis, tooth extracted, and radiographic assessment of the impacted tooth were recorded. Immediately after suture removal, the patients were invited to indicate their satisfaction on a Likert scale of 1-5. A total of 546 patients received extraction, and 251 patients were operated by associate dentists. Patient satisfaction was higher among those who had noncomplicated surgery (P=0.007), short treatment time (P<0.001), and had no postsurgical emergency appointments (P<0.001). The prevalence of seeking postsurgical eme...
Taq DNA polymerase, Sequenase, and the large fragment of E.coli polymerase I effectively utilize ... more Taq DNA polymerase, Sequenase, and the large fragment of E.coli polymerase I effectively utilize N4-methyl-2&#39;-deoxycytidine 5&#39;-triphosphate (N4-methyl-dCTP) in the place of dCTP in dideoxynucleotide terminator sequencing reactions on single-stranded templates. When the resulting fragment mixtures are resolved on sequencing gels, they are found to be free of band compressions even in cases where such compressions remain unresolved by the substitution of 7-deaza-dGTP for dGTP. Sequencing reactions using N4-methyl-dCTP instead of dCTP are somewhat more prone to false stops than are sequencing reactions using 7-deaza-dGTP instead of dGTP; this difference is more pronounced when sequencing with Sequenase at 37 degrees C than when sequencing with Taq DNA polymerase at 72 degrees C. For the three polymerases investigated, replacement of dCTP by N4-methyl-dCTP does not fundamentally change the characteristic variations in band intensities seen in the C-lane. N4-methyl-dCTP can also be used for sequencing double-stranded DNA and for DNA amplification by the polymerase chain reaction.
We aimed to establish community-based normal reference values of 24-h ambulatory blood pressure m... more We aimed to establish community-based normal reference values of 24-h ambulatory blood pressure monitoring (ABPM) for Chinese children and adolescents. Furthermore, we investigated how excluding overweight children affects BP percentiles and compared them with German references. In this territory-wide cross-sectional prospective cohort study, 1445 Hong Kong Chinese children and adolescents aged 8-17 years with body height between 119 and 185 cm were recruited. Their ABPM assessment was performed using validated arm oscillometric recorders (A&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;D TM-2430) and complied with American Heart Association&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s recommendations. The reference tables were constructed using the LMS method to normalize skewed distribution of ABP data to sex and age or height. The ambulatory BP was higher among boys and the difference between boys and girls progressively widened with age. An increasing trend in daytime and night-time SBP and DBP with age and height was observed in both sexes. The age-specific and sex-specific 95th percentiles from nonoverweight children (n=1147; 79%) were lower than the whole cohort by up to 2.5 and 1 mmHg for SBP and DBP, respectively. In comparison, our overall and nonoverweight reference standards were generally higher than corresponding German references. The study provides ambulatory BP standards for Chinese children, with sex-related age-specific and height-specific percentiles. Further longitudinal studies are required for investigating its clinical utility in Chinese.
The antidiabetic intestinal L cell hormone glucagon-like peptide-1 (GLP-1) enhances glucose-depen... more The antidiabetic intestinal L cell hormone glucagon-like peptide-1 (GLP-1) enhances glucose-dependent insulin secretion and inhibits gastric emptying. GLP-1 secretion is stimulated by luminal oleic acid (OA), which crosses the cell membrane by an unknown mechanism. We hypothesized that L cell fatty acid transport proteins (FATPs) are essential for OA-induced GLP-1 release. Therefore, the murine GLUTag L cell model was used for immunoblotting, [3H]OA uptake assay, and GLP-1 secretion assay as determined by radioimmunoassay following treatment with OA ± phloretin, sulfo- N-succinimidyl oleate, or siRNA against FATP4. FATP4−/− and cluster-of-differentiation 36 (CD36)−/− mice received intraileal OA, and plasma GLP-1 was measured by sandwich immunoassay. GLUTag cells were found to express CD36, FATP1, FATP3, and FATP4. The cells demonstrated specific 3H[OA] uptake that was dose-dependently inhibited by 500 and 1,000 μM unlabeled OA ( P < 0.001). Cell viability was not altered by treat...
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