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2.
Hong Kong Med J ; 30(4): 291-299, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39147587

RESUMO

INTRODUCTION: Type 2 diabetes mellitus (T2DM) is becoming increasingly common among children and adolescents worldwide, including those in Hong Kong. This study analysed the characteristics and prevalence of microvascular complications among paediatric T2DM patients in Hong Kong at diagnosis and 2 years after diagnosis. METHODS: All patients aged <18 years who had been diagnosed with DM at public hospitals in Hong Kong were recruited into the Hong Kong Childhood Diabetes Registry. Data collected at diagnosis and 2 years after diagnosis were retrospectively retrieved from the Registry for patients diagnosed from 2014 to 2018. RESULTS: Median haemoglobin A1c (HbA1c) levels were 7.5% (n=203) at diagnosis and 6.5% (n=135) 2 years after diagnosis; 59.3% of patients achieved optimal glycaemic control (HbA1c level <7%) at 2 years. A higher HbA1c level at diagnosis was associated with worse glycaemic control at 2 years (correlation coefficient=0.39; P<0.001). The presence of dyslipidaemia (adjusted odds ratio [aOR]=3.19; P=0.033) and fatty liver (aOR=2.50; P=0.021) at 2 years were associated with suboptimal glycaemic control. Diabetic neuropathy and retinopathy were rare in our cohort, but 18.6% of patients developed microalbuminuria (MA) within 2 years after diagnosis. Patients with MA had a higher HbA1c level at 2 years (median: 7.2% vs 6.4%; P=0.037). Hypertension was a risk factor for MA at 2 years, independent of glycaemic control (aOR=4.61; P=0.008). CONCLUSION: These results highlight the importance of early diagnosis and holistic management (including co-morbidity management) for paediatric T2DM patients.


Assuntos
Diabetes Mellitus Tipo 2 , Hemoglobinas Glicadas , Controle Glicêmico , Sistema de Registros , Humanos , Hong Kong/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Masculino , Feminino , Criança , Adolescente , Hemoglobinas Glicadas/análise , Estudos Retrospectivos , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/diagnóstico , Prevalência , Glicemia/análise , Fatores de Risco , Pré-Escolar
3.
Artigo em Inglês | MEDLINE | ID: mdl-39103504

RESUMO

PURPOSE: While some OVEMP recordings are morphologically straightforward, some are poor in appearance, which can create a challenge, as they often require a "second look" by another experienced assessor. Even OVEMPs in normal subjects are sometimes poorly formed, but we wondered if the morphological assessment of the OVEMP response might provide some additional diagnostic information. METHODS: A single experienced assessor evaluated the OVEMP recordings of 60 patients referred sequentially to a tertiary care centre, and categorized them as "easy to assess" (i.e. obvious to a minimally trained assessor) or "difficult to assess", often requiring a second look by another experienced assessor. RESULTS: In 48 patients, the results were easy to assess (regardless of the actual clinical results) while 12 were classified as "difficult". This figure reflected the rate of morphologically poor responses we found in our population of normative data. CONCLUSION: Our clinical concern is that many centres have given up relying on OVEMP assessment because the morphology of the wave may be challenging to interpret. OVEMP assessment often calls for a "second look", requiring a collaboration between two experienced assessors. It seems that this feature may not be diagnostically useful and poor OVEMP morphology may present a challenge in interpretation, but this should not be used as a reason to defer OVEMP testing.

4.
PLoS Biol ; 22(6): e3002641, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38833481

RESUMO

In utero exposure to maternal obesity programs increased obesity risk. Animal models show that programmed offspring obesity is preceded by hyperphagia, but the mechanisms that mediate these changes are unknown. Using a mouse model of maternal obesity, we observed increased intake of a high-fat diet (HFD) in offspring of obese mothers that precedes the development of obesity. Through small RNA sequencing, we identified programmed overexpression of hypothalamic miR-505-5p that is established in the fetus, lasts to adulthood and is maintained in hypothalamic neural progenitor cells cultured in vitro. Metabolic hormones and long-chain fatty acids associated with obesity increase miR-505-5p expression in hypothalamic neurons in vitro. We demonstrate that targets of miR-505-5p are enriched in fatty acid metabolism pathways and overexpression of miR-505-5p decreased neuronal fatty acid metabolism in vitro. miR-505-5p targets are associated with increased BMI in human genetic studies. Intra-cerebroventricular injection of miR-505-5p in wild-type mice increased HFD intake, mimicking the phenotype observed in offspring exposed to maternal obesity. Conversely, maternal exercise intervention in an obese mouse pregnancy rescued the programmed increase of hypothalamic miR-505-5p in offspring of obese dams and reduced HFD intake to control offspring levels. This study identifies a novel mechanism by which maternal obesity programs obesity in offspring via increased intake of high-fat foods.


Assuntos
Dieta Hiperlipídica , Ácidos Graxos , Hipotálamo , MicroRNAs , Obesidade Materna , Animais , Feminino , Humanos , Masculino , Camundongos , Gravidez , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos/metabolismo , Hipotálamo/metabolismo , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , MicroRNAs/genética , Neurônios/metabolismo , Obesidade/metabolismo , Obesidade/genética , Obesidade Materna/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/genética
5.
Childs Nerv Syst ; 40(3): 873-880, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37979014

RESUMO

PURPOSE: This study examines long-term benefit on functional outcomes and quality of life after selective dorsal rhizotomy (SDR) in children with spastic diplegia in Hong Kong. METHOD: This is a case control study. Individuals with spastic diplegia who were at 6 to 12 years post-SDR were recruited. Age, gender, cognition, and Gross Motor Function Classification System level-matched individuals with spastic diplegia who had not undergone SDR were recruited as controls. Outcome measures included physical level, functional level, physiological level, and quality of life. All data were compared by independent t-test. RESULTS: Individuals post-SDR (n = 15) demonstrated a significantly better range of ankle dorsiflexion in knee extension by - 5.7 ± 10.9° than the control group (n = 12). No other significant differences were observed. CONCLUSION: SDR is a safe, one-off procedure and provides long-term reduction in spasticity with no major complications. With the heterogeneity, we did not demonstrate between-group differences in long-term functional outcomes.


Assuntos
Paralisia Cerebral , Rizotomia , Criança , Humanos , Rizotomia/métodos , Estudos Retrospectivos , Estudos de Casos e Controles , Paralisia Cerebral/complicações , Qualidade de Vida , Espasticidade Muscular/cirurgia , Espasticidade Muscular/etiologia , Resultado do Tratamento
6.
Int J Food Sci ; 2023: 1797017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37350796

RESUMO

Date pits are agricultural waste byproducts and are available in tons yearly. Milk MUFAs are lipids beneficial for health and sorted out for food product development. This work is aimed at researching the effect of supplementing dairy goats with date pit powder (DPP) as a source of fatty acids (FA), an alternative to enhancing the unsaturated FA in milk and analysed via chemometrics in a 3-month supplementation-based study. Saanen-Boer crossed dairy goats were divided into six groups comprising of control, 10 g and 20 g both for Ajwa DPP (high-quality dates) and Mariami DPP (agricultural waste byproduct), and another 30 g for Mariami DPP only. The supplementation exercise was done daily on each dairy goat. The DPP and milk samples were analysed for its FA profile applying GC-FID and followed by chemometric techniques, namely, PCA and PLS. Results indicated that the n-6/n-3 ratio was the highest for the unsupplemented group compared to the DPP-treated goats with lower n-6/n-3 ratios. The M30 group showcased the most promising health-related class of FAs viewed by 3D PCA and PLS model clustering patterns, in particular monounsaturated FA (MUFA) (C18:1n9c or oleic acid). These results suggest that Mariami DPP supplementation at higher doses and time to lactating Saanen-Boer cross goats can be a means to milk FA quantity and quality enhancement and that chemometrics via pattern recognition can be useful statistical tools when dealing with overwhelming data.

7.
Appl Opt ; 62(8): 2061-2072, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-37133094

RESUMO

During subaperture tool grinding and polishing, overlaps of the tool influence function can result in undesirable mid-spatial frequency (MSF) errors in the form of surface ripples, which are often corrected using a smoothing polishing step. In this study, flat multi-layer smoothing polishing tools are designed and tested to simultaneously (1) reduce or remove MSF errors, (2) minimize surface figure degradation, and (3) maximize the material removal rate. A time-dependent convergence model in which spatial material removal varies with a workpiece-tool height mismatch, combined with a finite element mechanical analysis to determine the interface contact pressure distribution, was developed to evaluate various smoothing tool designs as a function of tool material properties, thicknesses, pad textures, and displacements. An improvement in smoothing tool performance is achieved when the gap pressure constant, h¯ (which describes the inverse rate at which the pressure drops with a workpiece-tool height mismatch), is minimized for smaller spatial scale length surface features (namely, MSF errors) and maximized for large spatial scale length features (i.e., surface figure). Five specific smoothing tool designs were experimentally evaluated. A two-layer smoothing tool using a thin, grooved IC1000 polyurethane pad (with a high elastic modulus, E p a d =360M P a), thicker blue foam (with an intermediate modulus, E f o a m =5.3M P a) underlayer, and an optimized displacement (d t=1m m) provided the best overall performance (namely, high MSF error convergence, minimal surface figure degradation, and high material removal rate).

8.
Ultrasound Obstet Gynecol ; 62(5): 727-738, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37058402

RESUMO

OBJECTIVE: To describe the clinical and sonographic characteristics of benign, retroperitoneal, pelvic peripheral-nerve-sheath tumors (PNSTs). METHODS: This was a retrospective study of patients with a benign, retroperitoneal, pelvic PNST who had undergone preoperative ultrasound examination at a single gynecologic oncology center between 1 January 2018 and 31 August 2022. All ultrasound images, videoclips and final histological specimens of benign PNSTs were reviewed side-by-side in order to: describe the ultrasound appearance of the tumors, using the terminology of the International Ovarian Tumor Analysis (IOTA), Morphological Uterus Sonographic Assessment (MUSA) and Vulvar International Tumor Analysis (VITA) groups, following a predefined ultrasound assessment form; describe their origin in relation to nerves and pelvic anatomy; and assess the association between their ultrasound features and histotopography. A review of the literature reporting benign, retroperitoneal, pelvic PNSTs with preoperative ultrasound examination was performed. RESULTS: Five women (mean age, 53 years) with a benign, retroperitoneal, pelvic PNST were identified, four with a schwannoma and one with a neurofibroma, of which all were sporadic and solitary. All patients had good-quality ultrasound images and videoclips and final biopsy of surgically excised tumors, except one patient managed conservatively who had only a core needle biopsy. In all cases, the findings were incidental. The five PNSTs ranged in maximum diameter from 31 to 50 mm. All five PNSTs were solid, moderately vascular tumors, with non-uniform echogenicity, well-circumscribed by hyperechogenic epineurium and with no acoustic shadowing. Most of the masses were round (n = 4 (80%)), and contained small, irregular, anechoic, cystic areas (n = 3 (60%)) and hyperechogenic foci (n = 5 (100%)). In the woman with a schwannoma in whom surgery was not performed, follow-up over a 3-year period showed minimal growth (1.5 mm/year) of the mass. We also summarize the findings of 47 cases of benign retroperitoneal schwannoma and neurofibroma identified in a literature search. CONCLUSIONS: On ultrasound examination, no imaging characteristics differentiate reliably between benign schwannomas and neurofibromas. Moreover, benign PNSTs show some similar features to malignant retroperitoneal tumors. They are solid lesions with intralesional blood vessels and show degenerative changes such as cystic areas and hyperechogenic foci. Therefore, ultrasound-guided biopsy may play a pivotal role in their diagnosis. If confirmed to be benign PNSTs, these tumors can be managed conservatively, with ultrasound surveillance. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Neoplasias de Bainha Neural , Neurilemoma , Neurofibroma , Neoplasias Pélvicas , Neoplasias Retroperitoneais , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Retroperitoneais/diagnóstico por imagem , Neoplasias de Bainha Neural/diagnóstico , Neoplasias de Bainha Neural/patologia , Neoplasias de Bainha Neural/cirurgia , Neurofibroma/diagnóstico , Neurofibroma/patologia , Neurofibroma/cirurgia , Neurilemoma/diagnóstico por imagem , Neurilemoma/patologia , Ultrassonografia
10.
Eur J Pediatr ; 182(4): 1719-1730, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36757493

RESUMO

Cerebral palsy (CP) is an early onset, non-progressive, neuromotor disorder. Adolescence is the transition from childhood to adulthood when changes in physical and emotional aspects and self-perception occur further imposing an impact to quality of life (QoL) in individuals with CP. Cerebral Palsy Quality of Life (CP QoL) Teen is a questionnaire examining different domains of QoL for adolescents with CP. This study is aimed at translating and validating self-report and proxy-report CP QoL-Teen (HK). Prior approval of translation has been obtained. Forward and backward translations were performed following standardized translation procedures. Participants and their caregivers were asked to complete self-report and proxy-report CP QoL-Teen (HK), and Child Health Questionnaire (CHQ). Internal consistency and test-retest reliability were assessed by Cronbach's alpha and intraclass correlation coefficient (ICC), respectively. Concurrent validity was evaluated by Spearman's rank correlation between subscales of CP QoL-Teen (HK) and CHQ as well as expanded and revised version of Gross Motor Function Classification System (GMFCS-E&R). Ninety-six participants completed the study. Of these, twenty participants completed CP QoL-Teen (HK) twice. Cronbach's α of CP QoL-Teen (HK) ranged from 0.84 to 0.95 suggesting excellent internal consistency. Moderate to excellent test-retest reliability were demonstrated in all subscales of CP QoL-Teen (HK) (self-report: ICC = 0.46-0.8; proxy-report: ICC = 0.40-0.72, p < 0.05). Weak to moderate association between subscales of CP QoL-Teen (HK) and CHQ (self-report: rs = 0.24-0.61; proxy-report: rs = - 0.41-0.60) was reported. CONCLUSION: This study showed that CP QoL-Teen (HK) has good psychometric properties. It is a valid and reliable tool to assess quality of life of adolescents with CP. WHAT IS KNOWN: • Cerebral Palsy Quality of life-Teen (CP QoL-Teen) is a validated tool with strong psychometric properties and clinical utility in gauging the QoL in adolescents with CP during their transition from childhood to adulthood when changes in physical and emotional aspects and self-perception occur. Yet, a locally validated tool is lacking in measuring the QoL for adolescents with CP in Hong Kong. WHAT IS NEW: • The Chinese translated version CP QoL-Teen (HK) is a valid and reliable tool to assess quality of life of adolescents with CP tailoring to the local cultural and social background with good psychometric properties being demonstrated.


Assuntos
Paralisia Cerebral , Qualidade de Vida , Inquéritos e Questionários , Adolescente , Criança , Humanos , Adulto Jovem , População do Leste Asiático , Hong Kong , Psicometria/métodos , Qualidade de Vida/psicologia , Reprodutibilidade dos Testes , Traduções
12.
Appl Opt ; 62(1): 91-101, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36606856

RESUMO

The tool influence function (TIF) during sub-aperture belt-on-wheel polishing has been evaluated as a function of various process conditions (belt use/wear, dwell time, displacement, belt velocity, and wheel modulus and diameter) on fused silica glass workpieces using C e O 2 polishing media. TIF spots are circular or elliptical in shape with a largely flat bottom character. The volumetric removal rate varies significantly with belt use (or wear), stabilizing after ∼15m i n of use. A modified Preston model, where the pressure dependence is adjusted using a different scaling of the wheel modulus (E w0.5), largely predicts the volumetric removal rate over the range of process conditions evaluated. The relatively high volumetric removal rate of 30-60m m 3/h using a fixed C e O 2-in-resin-host belt offers a rapid, and hence, more economical, initial polish of aspheric and freeform optics.

13.
Clin Ter ; 174(1): 61-66, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36655646

RESUMO

Aim: With the characteristics such as low toxicity, high total surface, ability to inhibit the growth of pathogenic microorganisms, zinc oxide nanoparticles (ZnO NPs), as one of the metallic nanoparticles, have been chosen as an antibacterial agent to treat various skin infections. The present study was aimed to determine the antibacterial potential of ZnO NPs on Bacillus subtilis, the Gram-positive bacterium that can cause skin and wound infections. Methods: B. subtilis was exposed to 5 to 150 µg/mL of ZnO NPs for 24 h. The parameters employed to evaluate the antimicrobial potential of ZnO NPs were the growth inhibitory effect on B. subtilis, the surface interaction of ZnO NPs on the bacterial cell wall, and also the morphological alterations in B. subtilis induced by ZnO NPs. Results: The results demonstrated a significant (p <0.05) inhibition of ZnO NPs on B. subtilis growth and it was in a dose-dependent manner for all the tested concentrations of ZnO NPs from 5 to 150 µg/mL at 24 h. Fourier transformed infrared (FTIR) spectrum confirmed the involvement of polysaccharides and polypeptides of bacterial cell wall in surface binding of ZnO NPs on bacteria. The scanning electron microscopy (SEM) was used to visualize the morphological changes, B. subtilis illustrated several surface alterations such as distortion of cell membrane, roughening of cell surface, aggregation and bending of cells, as well as, the cell rupture upon interacting with ZnO NPs for 24 h. Conclusion: The results indicated the potential of ZnO NPs to be used as an antibacterial agent against B. subtilis. The findings of the present study might bring insights to incorporate ZnO NPs as an antibacterial agent in the topical applications against the infections caused by B. subtilis.


Assuntos
Nanopartículas Metálicas , Óxido de Zinco , Humanos , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Óxido de Zinco/metabolismo , Bacillus subtilis/metabolismo , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/química , Antibacterianos/farmacologia
14.
Public Health ; 213: 1-4, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36308872

RESUMO

OBJECTIVES: This study aimed to study the public's sentiments on the current monkeypox outbreaks via an unsupervised machine learning analysis of social media posts. STUDY DESIGN: This was an exploratory analysis of tweets sentiments. METHODS: We extracted original tweets containing the terms 'monkeypox', 'monkey pox' or 'monkey_pox' and posted them in the English language from 6 May 2022 (first case detected in the United Kingdom) to 23 July 2022 (when World Health Organization declared Monkeypox to be a global health emergency). Retweets and duplicate tweets were excluded from study. Bidirectional Encoder Representations from Transformers (BERT) Named Entity Recognition. This was followed by topic modelling (specifically BERTopic) and manual thematic analysis by the study team, with independent reviews of the topic labels and themes. RESULTS: Based on topic modelling and thematic analysis of a total of 352,182 Twitter posts, we derived five topics clustered into three major themes related to the public discourse on the ongoing outbreaks. These include concerns of safety, stigmatisation of minority communities, and a general lack of faith in public institutions. The public sentiments underscore growing (and existing) partisanship, personal health worries in relation to the evolving situation, as well as concerns of the media's portrayal of lesbian, gay, bisexual, transgender and queer and minority communities, which might further stigmatise these groups. CONCLUSIONS: Monkeypox is an emerging infectious disease of public concern. Our study has highlighted important societal issues, including misinformation, political mistrust and anti-gay stigma that should be sensitively considered when designing public health policies to contain the ongoing outbreaks.


Assuntos
Grupos Minoritários , Aprendizado de Máquina não Supervisionado , Humanos , Animais , Política Pública , Haplorrinos , Reino Unido/epidemiologia
15.
Bioorg Chem ; 125: 105915, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35660840

RESUMO

To improve pironetin's metabolic stability we prepared four analogs by replacing its C12-14 segment with an aryl group. The antiproliferative activity of phenyl analog 4 was reduced two-fold and dihydroxy-4-fluorophenyl analog 5 was slightly more effective against OVCAR5 and A2780 ovarian cancer cell lines compared with the parent compound pironetin (1). The activity of 4-fluorophenyl analog 6 was reduced 3-fold in both cell lines. The activity of 7-O-methyl analog 7 was reduced 36-fold in OVCAR5 cells and 47-fold and A2780 cells, compared with pironetin. Phenylpironetin (4) was rapidly metabolized by mouse and human liver microsomes. We identified 17 human metabolites for phenyl analog 4 and 14 human metabolites for pironetin. Metabolism occurred at the C12-13 moiety, the α,ß-unsaturated lactone and the side chains of the molecules (C6-C11 segments). The significant extent of oxidative metabolism suggests that it may not be possible to attain a metabolically stable pironetin analog by structural modifications of the parent compound.


Assuntos
Neoplasias Ovarianas , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Lactonas , Camundongos , Pironas/química
16.
Ultrasound Obstet Gynecol ; 60(2): 200-206, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35468236

RESUMO

OBJECTIVE: To assess whether pregnancy-associated plasma protein-A (PAPP-A) alters or provides equivalent screening performance as placental growth factor (PlGF) when screening for preterm pre-eclampsia (PE) at 11-13 weeks of gestation. METHODS: This was a secondary analysis of a non-intervention screening study of 6546 singleton pregnancies that were screened prospectively for preterm PE in the first trimester between December 2016 and June 2018. Patient-specific risks for preterm PE were estimated by maternal history, mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI), PlGF and PAPP-A. A competing-risks model with biomarkers expressed as multiples of the median was used. All women and clinicians were blinded to the risk for preterm PE. The performance of screening for preterm PE using PlGF vs PAPP-A vs both PAPP-A and PlGF was assessed by comparing areas under the receiver-operating-characteristics (AUC) curves. McNemar's test was used to compare detection rate at a fixed false-positive rate (FPR) of 10%. RESULTS: PlGF and PAPP-A were measured in 6546 women, of whom 37 developed preterm PE. The AUC and detection rate at 10% FPR using PlGF in combination with maternal history, MAP and UtA-PI were 0.854 and 59.46%, respectively. The respective values were 0.813 and 51.35% when replacing PlGF with PAPP-A and 0.855 and 59.46% when using both PAPP-A and PlGF. Statistically non-significant differences were noted in AUC when replacing PlGF with PAPP-A (ΔAUC, 0.04; P = 0.095) and when using both PAPP-A and PlGF (ΔAUC, 0.002; P = 0.423). However, on an individual case basis, screening using PlGF in conjunction with maternal history, MAP and UtA-PI identified three (8.1%) additional pregnancies that developed preterm PE and that were not identified when replacing PlGF with PAPP-A. Screening using PAPP-A in addition to maternal history and other biomarkers did not identify any additional pregnancies. CONCLUSION: On an individual case basis, adoption of a screening strategy that uses PAPP-A instead of PlGF results in reduced detection of preterm PE, consistent with previous literature. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Pré-Eclâmpsia , Proteína Plasmática A Associada à Gravidez , Biomarcadores , Feminino , Humanos , Recém-Nascido , Fator de Crescimento Placentário , Gravidez , Primeiro Trimestre da Gravidez , Fluxo Pulsátil , Artéria Uterina/diagnóstico por imagem
17.
Appl Opt ; 61(11): 3084-3095, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35471283

RESUMO

During sub-aperture tool polishing of glass optics, mid-spatial surface ripples are generated because of material removal non-uniformities during tool linear translation (resulting in feed ripples) and tool pathway step overlaps (resulting in pitch ripples). A variety of tool influence function (TIF) spots, trenches, and patches were created to understand and minimize such ripples on fused silica workpieces after polishing with cerium oxide slurry using a rotating hemispherical pad-foam tool. The feed ripple amplitude can be decreased by reducing the non-uniformities in the pad texture and/or by minimizing a derived feed ripple metric (rf=Vmax0.5Vf/Rt) via adjustments in processing parameters. Pitch ripples can be minimized by reducing relative step distance to spot radius ratio (xs/at) and by achieving a flat bottom trench shape cross section or by reducing the material removal per pass. Using the combined methods, an overall ripple error of ∼1.2nm rms has been achieved.

18.
Prenat Diagn ; 42(7): 862-872, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35441720

RESUMO

OBJECTIVE: The diagnostic yield for congenital heart defects (CHD) with routine genetic testing is around 10%-20% when considering pathogenic CNVs or aneuploidies as positive findings. This is a pilot study to investigate the utility of genome sequencing (GS) for prenatal diagnosis of CHD. METHODS: Genome sequencing (GS, 30X) was performed on 13 trios with CHD for which karyotyping and/or chromosomal microarray results were non-diagnostic. RESULTS: Trio GS provided a diagnosis for 4/13 (30.8%) fetuses with complex CHDs and other structural anomalies. Findings included pathogenic or likely pathogenic variants in DNAH5, COL4A1, PTPN11, and KRAS. Of the nine cases without a genetic etiology by GS, we had outcome follow-up data on eight. For five of them (60%), the parents chose to keep the pregnancy. A balanced translocation [46,XX,t(14; 22)(q32.33; q13.31)mat] was detected in a trio with biallelic DNAH5 mutations, which together explained the recurrent fetal situs inversus and dextrocardia that was presumably due to de novo Phelan-McDermid syndrome. A secondary finding of a BRCA2 variant and carrier status of HBB, USH2A, HBA1/HBA2 were detected in the cohort. CONCLUSIONS: GS expands the diagnostic scope of mutation types over conventional testing, revealing the genetic etiology for fetal heart anomalies. Patients without a known genetic abnormality indicated by GS likely opted to keep pregnancy especially if the heart defect could be surgically repaired. We provide evidence to support the application of GS for fetuses with CHD.


Assuntos
Doenças Fetais , Cardiopatias Congênitas , Aberrações Cromossômicas , Variações do Número de Cópias de DNA , Feminino , Coração Fetal , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/genética , Humanos , Projetos Piloto , Gravidez , Diagnóstico Pré-Natal/métodos
19.
Hong Kong Med J ; 28(2): 140-151, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35400642

RESUMO

INTRODUCTION: The surveillance of antibiotic resistance is critical for the establishment of effective control strategies. The antibiotic resistance situations in private hospitals in Hong Kong have not been systematically described. The objective of the study was to analyse antibiogram data from private hospitals and describe the temporal trends of non-susceptibility percentages in this setting. METHODS: This retrospective descriptive study used antibiogram data from all private hospitals in Hong Kong that had been collected annually for 6 years (2014-2019). Data on six targeted bacteria and their corresponding multidrug-resistant organisms were included. RESULTS: The non-susceptibility percentages of isolates remained stable or decreased during the study period: methicillin-resistant Staphylococcus aureus had a stable prevalence of approximately 20%; extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella species had stable prevalences of 20% to 30% and 10% to 20%, respectively; multidrug-resistant Acinetobacter species had prevalences of approximately 2% to 8%, which decreased over time; multidrug-resistant Pseudomonas aeruginosa had prevalences of 0.0% to 0.3%; Streptococcus pneumoniae penicillin and macrolide non-susceptibility percentages were 2% to 9% and 71% to 79%, respectively. These values generally were comparable with findings from public hospitals and Residential Care Homes for the Elderly in Hong Kong. However, the prevalences of carbapenem-resistant Enterobacteriaceae, which are increasing in Hong Kong and other nations, were also increasing in our dataset despite their currently low values (<1% for Escherichia coli and <2% for Klebsiella species). CONCLUSION: The antibiotic resistance landscape among private hospitals in Hong Kong is satisfactory overall; there remains a need for surveillance, antibiotic stewardship, and other infection control measures.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Escherichia coli , Hong Kong/epidemiologia , Hospitais Privados , Humanos , Testes de Sensibilidade Microbiana , Estudos Retrospectivos
20.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(1): 140-145, 2022 Feb 18.
Artigo em Chinês | MEDLINE | ID: mdl-35165481

RESUMO

OBJECTIVE: To analyze the marginal roughness and marginal fitness of chairside computer-aided design and computer-aided manufacturing (CAD/CAM) laminate veneers with different materials and thicknesses, and to provide a reference for the clinical application of laminate veneers. METHODS: The butt-to-butt type laminate veneers were prepared on resin typodonts, the preparations were scanned, and the laminate veneers were manufactured by chairside CAD/CAM equipment. The laminate veneers were divided into four groups (n=9) according to the materials (glass-matrix ceramics and resin-matrix ceramics) and thickness (0.3 mm and 0.5 mm) of the veneers, with a total of 36. The marginal topo-graphies of each laminate veneer were digitally recorded by stereomicroscope, and the marginal rough-nesses of the laminate veneers were determined by ImageJ software. The marginal fitness of the laminate veneers was measured by a fit checker and digital scanning and measuring method. At the same time, the mechanical properties of glass-matrix ceramic and resin-matrix ceramic bars (n=20) were tested by a universal testing device. RESULTS: The marginal roughness of 0.3 mm and 0.5 mm glass-matrix ceramic laminate veneers was (24.48±5.55) µm and (19.06±5.75) µm, respectively, with a statistically significant difference (P < 0.001). The marginal roughness of 0.3 mm and 0.5 mm resin-matrix ceramic laminate veneers was (6.13±1.27) µm and (6.84±2.19) µm, respectively, without a statistically significant difference (P>0.05). The marginal roughness of the glass-matrix ceramic laminate veneers was higher than that of the resin-matrix ceramic laminate veneers with a statistically significant difference (P < 0.001). The marginal fitness of 0.3 mm and 0.5 mm glass-matrix ceramic laminate veneers were (66.30±26.71) µm and (85.48±30.44) µm, respectively. The marginal fitness of 0.3 mm and 0.5 mm resin-matrix ceramic laminate veneers were (56.42±19.27) µm and (58.36±8.33) µm, respectively. There was no statistically significant difference among the 4 groups (P>0.05). For glass-matrix ceramics, the flexural strength was (327.40±54.25) MPa, the flexural modulus was (44.40±4.39) GPa, and the modulus of resilience was (1.24±0.37) MPa. For resin-matrix ceramics, the flexural strength was (173.71±16.61) MPa, the flexural modulus was (11.88±0.51) GPa, and the modulus of resilience was (1.29±0.27) MPa. The flexural strength and modulus of glass-matrix ceramics were significantly higher than those of resin-matrix ceramics (P < 0.001), but there was no statistically significant difference in the modulus of resilience between the two materials (P>0.05). CONCLUSION: The marginal roughness of CAD/CAM glass-matrix ceramic laminate veneers is greater than that of resin-matrix ceramic laminate veneers, but there was no statistically significant difference in marginal fitness among them. Increasing the thickness can reduce the marginal roughness of glass-matrix ceramic laminate veneers, but has no effect on the marginal roughness of resin-matrix ceramic laminate veneers.


Assuntos
Cerâmica , Desenho Assistido por Computador , Porcelana Dentária , Facetas Dentárias , Teste de Materiais , Propriedades de Superfície
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