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1.
Anesthesiology ; 140(4): 690-700, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38150544

RESUMO

BACKGROUND: Propofol is an intravenous anesthetic associated with hypotension, respiratory depression, and injection-site pain. HSK3486 injectable emulsion (ciprofol) is a 2,6-disubstituted phenol derivative with fast onset and quick, stable recovery. Previous studies support HSK3486 as an effective, safe anesthetic with substantially less injection-site pain than propofol. The primary objective of this study was to investigate the noninferiority of HSK3486 compared with propofol in successful general anesthesia induction. METHODS: Two hundred fifty-five participants were enrolled in HSK3486-304, a multicenter, randomized (2:1), double-blind, propofol-controlled, phase 3 study evaluating HSK3486 for general anesthesia induction in adults undergoing elective surgery with tracheal intubation. The primary endpoint was successful anesthesia induction, defined as 1 or less on the Modified Observer's Assessment of Alertness/Sedation scale. Key secondary endpoints were proportion of participants with injection-site pain on the Numerical Rating Scale of 1 or greater and a composite endpoint, including the proportion of participants successfully induced while maintaining the desired anesthetic depth and without substantial cardiac and respiratory events. Safety endpoints included adverse events, abnormal vital signs, and injection-site pain. RESULTS: Two hundred fifty-one participants (HSK3486, n = 168; propofol, n = 83) were included in the analyses. General anesthesia was successfully induced in 97.0% versus 97.6% of participants with HSK3486 and propofol, respectively. The difference in success rate was -0.57% (95% CI, -5.4 to 4.2%); the noninferiority boundary of -8% was not crossed. Thirty participants (18.0%) had injection-site pain with HSK3486 versus 64 (77.1%) with propofol (P < 0.0001). Eighty-one participants (48.2%) with HSK3486 versus 42 (50.6%) with propofol (P = 0.8780) satisfied the composite endpoint. When injection-site pain was excluded, the incidence of treatment-emergent adverse events related to study drug was 17.9% for HSK3486 and 14.5% for propofol. CONCLUSIONS: The study met its primary objective and endpoint, demonstrating noninferiority of HSK3486 compared with propofol in successful anesthetic induction. Substantially less injection-site pain was associated with HSK3486 than with propofol.


Assuntos
Hipotensão , Propofol , Adulto , Humanos , Propofol/efeitos adversos , Anestésicos Intravenosos/efeitos adversos , Dor/tratamento farmacológico , Anestesia Geral/efeitos adversos , Hipotensão/complicações , Método Duplo-Cego
2.
J Formos Med Assoc ; 121(3): 613-622, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34332829

RESUMO

BACKGROUND: Healthcare personnel (HCP) at the front line of care are exposed to occupational hazards that place them at risk for infection, which then endanger patient safety and compromise the capability of the healthcare workforce. As of March 8, 2021 more than 420,170 HCP in US had been infected with SARS CoV-2 with 1388 deaths. In two Taiwan hospitals COVID-19 outbreaks involved HCP and resulted in shutdown of service. This report describes our prospective health surveillance of the HCP and COVID-19 containment measures in a teaching hospital in Taiwan during Jan. 1 through June 30, 2020. METHODS: We prospectively monitored incidents, defined as an HCP with the predefined symptoms, reported by HCP through the web-based system. HCP were managed based on an algorithm that included SARS CoV-2 RNA PCR testing. Infection prevention and control policy/practice were reviewed. RESULTS: This hospital took care of 17 confirmed COVID-19 cases during the study period and the first Case was admitted on January 23, 2020. Among the 14,210 HCP, there were 367 incident events. Of 283 HCP tested for SARS CoV-2, 179 had predefined symptoms. These included 10 HCP who met the national case definition for COVID-19 infection and 169 based on Extended COVID-19 Community Screening program. The other 104 asymptomatic HCP were tested based on hospital policy. All of them had tested negative. CONCLUSION: We attribute our success in preventing COVID-19 infections among HCP to rapid, proactive, decisive, integrated national and institutional response in the early stages of the epidemic.


Assuntos
COVID-19 , Centros Médicos Acadêmicos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pessoal de Saúde , Humanos , Estudos Prospectivos , SARS-CoV-2 , Taiwan/epidemiologia
3.
J Chem Phys ; 155(7): 074701, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34418937

RESUMO

We studied the dissociation of water (H2O*, with * denoting adspecies) on atomic oxygen (O*)-covered Rh nanoclusters (RhO* ) supported on a graphene film grown on a Ru(0001) surface [G/Ru(0001)] under ultrahigh-vacuum conditions and with varied surface-probe techniques and calculations based on density-functional theory. The graphene had a single rotational domain; its lattice expanded by about 5.7% to match the Ru substrate structurally better. The Rh clusters were grown by depositing Rh vapors onto G/Ru(0001); they had an fcc phase and grew in (111) orientation. Water adsorbed on the Rh clusters was dissociated exclusively in the presence of O*, like that on a Rh(111) single-crystal surface. Contrary to the case on Rh(111)O* , excess O* (even at a saturation level) on small RhO* clusters (diameter of 30-34 Å) continued to promote, instead of inhibiting, the dissociation of water; the produced hydroxyl (OH*) increased generally with the concentration of O* on the clusters. The difference results from more reactive O* on the RhO* clusters. O* on RhO* clusters activated the dissociation via both the formation of hydrogen bonds with H2O* and abstraction of H directly from H2O*, whereas O* on Rh(111)O* assisted the dissociation largely via the formation of hydrogen bonds, which was readily obstructed with an increased O* coverage. As the disproportionation (2 OH* → H2O* + O*) is endothermic on the RhO* clusters but exothermic on Rh(111)O* , OH* produced on RhO* clusters showed a thermal stability superior to that on the Rh(111)O* surface-thermally stable up to 400 K.

4.
Int J Mol Sci ; 22(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072831

RESUMO

Although histone deacetylase 8 (HDAC8) plays a role in glioblastoma multiforme (GBM), whether its inhibition facilitates the treatment of temozolomide (TMZ)-resistant GBM (GBM-R) remains unclear. By assessing the gene expression profiles from short hairpin RNA of HDAC8 in the new version of Connectivity Map (CLUE) and cells treated by NBM-BMX (BMX)-, an HDAC8 inhibitor, data analysis reveals that the Wnt signaling pathway and apoptosis might be the underlying mechanisms in BMX-elicited treatment. This study evaluated the efficacy of cotreatment with BMX and TMZ in GBM-R cells. We observed that cotreatment with BMX and TMZ could overcome resistance in GBM-R cells and inhibit cell viability, markedly inhibit cell proliferation, and then induce cell cycle arrest and apoptosis. In addition, the expression level of ß-catenin was reversed by proteasome inhibitor via the ß-catenin/ GSK3ß signaling pathway to reduce the expression level of c-Myc and cyclin D1 in GBM-R cells. BMX and TMZ cotreatment also upregulated WT-p53 mediated MGMT inhibition, thereby triggering the activation of caspase-3 and eventually leading to apoptosis in GBM-R cells. Moreover, BMX and TMZ attenuated the expression of CD133, CD44, and SOX2 in GBM-R cells. In conclusion, BMX overcomes TMZ resistance by enhancing TMZ-mediated cytotoxic effect by downregulating the ß-catenin/c-Myc/SOX2 signaling pathway and upregulating WT-p53 mediated MGMT inhibition. These findings indicate a promising drug combination for precision personal treating of TMZ-resistant WT-p53 GBM cells.


Assuntos
Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioblastoma/tratamento farmacológico , Histona Desacetilases/genética , Proteínas Repressoras/genética , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , beta Catenina/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Proteínas Repressoras/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Temozolomida/efeitos adversos , Temozolomida/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Phys Chem Chem Phys ; 20(2): 1261-1266, 2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-29250624

RESUMO

The dissociation of water molecules absorbed on a cleaved non-polar GaN(11[combining macron]00) surface was studied primarily with synchrotron-based photoemission spectra and density-functional-theory calculations. The adsorbed water molecules are spontaneously dissociated into hydrogen atoms and hydroxyl groups at either 300 or 130 K, which implies a negligible activation energy (<11 meV) for the dissociation. The produced H and OH were bound to the surface nitrogen and gallium on GaN(11[combining macron]00) respectively. These results highlight the promising applications of the non-polar GaN(11[combining macron]00) surface in water dissociation and hydrogen generation.

6.
Phys Chem Chem Phys ; 19(22): 14566-14579, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28537293

RESUMO

Self-organized alloying of Au with Rh in nanoclusters on an ordered thin film of Al2O3/NiAl(100) was investigated via various surface probe techniques under ultrahigh-vacuum conditions and calculations based on density-functional theory. The bimetallic clusters were formed on the sequential deposition of vapors of Au and Rh onto Al2O3/NiAl(100) at 300 K. The formation was more effective on the oxide seeded with Rh, since all post-deposited Au joined the pregrown Rh clusters; for metal deposition in the reverse order, some separate Rh clusters were formed. The contrasting behavior is rationalized through the easier nucleation of Rh on the oxide surface, due to the stronger Rh-oxide and Rh-Rh bonds. The alloying in the clusters proceeded, regardless of the order of metal deposition, toward a specific structure: an fcc phase, (100) orientation and Rh core-Au shell structure. The orientation, structural ordering and lattice parameters of the Au-Rh bimetallic clusters resembled Rh clusters, rather than Au clusters, on Al2O3/NiAl(100), even with Rh in a minor proportion. The Rh-predominated core-shell structuring corresponds to the binding energies in the order Rh-Rh > Rh-Au > Au-Au. The core-shell segregation, although active, was somewhat kinetically hindered, since elevating the sample temperature induced further encapsulation of Rh. The bimetallic clusters became thermally unstable above 500 K, for which both Rh and Au atoms began to diffuse into the substrate. Moreover, the electronic structures of surface elements on the bimetallic clusters, controlled by both structural and electronic effects, show a promising reactivity.

7.
Nat Commun ; 15(1): 653, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253575

RESUMO

Transition metal dichalcogenides, by virtue of their two-dimensional structures, could provide the largest active surface for reactions with minimal materials consumed, which has long been pursued in the design of ideal catalysts. Nevertheless, their structurally perfect basal planes are typically inert; their surface defects, such as under-coordinated atoms at the surfaces or edges, can instead serve as catalytically active centers. Here we show a reaction probability > 90 % for adsorbed methanol (CH3OH) on under-coordinated Pt sites at surface Te vacancies, produced with Ar+ bombardment, on layered PtTe2 - approximately 60 % of the methanol decompose to surface intermediates CHxO (x = 2, 3) and 35 % to CHx (x = 1, 2), and an ultimate production of gaseous molecular hydrogen, methane, water and formaldehyde. The characteristic reactivity is attributed to both the triangular positioning and varied degrees of oxidation of the under-coordinated Pt at Te vacancies.

8.
ACS Appl Mater Interfaces ; 15(12): 16153-16161, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36802501

RESUMO

Layered transition metal dichalcogenides (TMDs) are two-dimensional materials exhibiting a variety of unique features with great potential for electronic and optoelectronic applications. The performance of devices fabricated with mono or few-layer TMD materials, nevertheless, is significantly affected by surface defects in the TMD materials. Recent efforts have been focused on delicate control of growth conditions to reduce the defect density, whereas the preparation of a defect-free surface remains challenging. Here, we show a counterintuitive approach to decrease surface defects on layered TMDs: a two-step process including Ar ion bombardment and subsequent annealing. With this approach, the defects, mainly Te vacancies, on the as-cleaved PtTe2 and PdTe2 surfaces were decreased by more than 99%, giving a defect density <1.0 × 1010 cm-2, which cannot be achieved solely with annealing. We also attempt to propose a mechanism behind the processes.

9.
ACS Appl Mater Interfaces ; 14(14): 16901-16910, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35357129

RESUMO

Organic-molecular magnets based on a metal-organic framework with chemically tuned electronic and magnetic properties have been attracting tremendous attention due to their promising applications in molecular magnetic sensors, magnetic particle medicines, molecular spintronics, etc. Here, we investigated the magnetic behavior of a heterojunction comprising a ferromagnetic nickel (Ni) film and an organic semiconductor (OSC) 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) layer. Through the magneto-optical Kerr effect (MOKE), a photoemission electron microscopy (PEEM), X-ray magnetic circular dichroism (XMCD), and X-ray photoelectron spectroscopy (XPS), we found that the adsorption of F4-TCNQ on Cu(100)/Ni not only reverses the in-plane magnetization direction originally exhibited by the Ni layer but also results in enhanced magnetic ordering. Furthermore, the cyano group (CN) in adsorbed F4-TCNQ was found spin-polarized along with conspicuous charge transfer with Ni. The density functional theory (DFT) calculations suggest that the experimentally found spin polarization originates from hybridization between the CN group's π orbitals and Ni's d band. These findings signify that the hybrid states at the organic-ferromagnet interface play a key role in tailoring the magnetic behavior of interfaces. For the case of the F4-TCNQ and Ni heterojunction reported here, interface coupling is an antiferromagnetic one.

10.
RSC Adv ; 11(40): 24762-24771, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35481058

RESUMO

Annealed Rh nanoclusters on an ordered thin film of Al2O3/NiAl(100) were shown to exhibit a promoted reactivity toward the decomposition of methanol-d4, under both ultrahigh vacuum and near-ambient-pressure conditions. The Rh clusters were grown with vapor deposition onto the Al2O3/NiAl(100) surface at 300 K and annealed to 700 K. The decomposition of methanol-d4 proceeded only through dehydrogenation, with CO and deuterium as products, on Rh clusters both as prepared and annealed. Nevertheless, the catalytic reactivity of the annealed clusters, measured with the production of either CO or deuterium per surface Rh site from the reaction, became at least 2-3 times that of the as-prepared ones. The promoted reactivity results from an altered support effect associated with an annealing-induced mass transport at the surface. Our results demonstrate a possibility to practically prepare reactive Rh clusters, regardless of the cluster size, that can tolerate an elevated reaction temperature, with no decreased reactivity.

11.
Phys Rev Lett ; 104(17): 177204, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20482136

RESUMO

To emulate the interfacial regimes of a Co/Pc/Co spin-valve structure, we fabricated ultrathin pentacene/cobalt (Pc/Co) and cobalt/pentacene (Co/Pc) bilayers. Through measurement of the magneto-optical Kerr effect, we found the Co layer has its magnetic properties depend strongly upon the order of deposition. Further x-ray spectroscopy and microscopy investigation indicated Co/Pc was chemically stable, whereas Pc/Co was reactive and exhibited complex magnetization pattern. The different chemistry and magnetic configurations at interfaces could cause additional complication for spin injection.

12.
RSC Adv ; 10(30): 17787-17794, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35515600

RESUMO

We have studied the reforming reaction of ethanol co-adsorbed with atomic oxygen (O*, * denotes adspecies) and deuterated water (D2O*) on a Rh(111) surface, with varied surface probe techniques under UHV conditions and with density-functional-theory calculations. Adsorbed ethanol molecules were found to penetrate readily through pre-adsorbed water, even up to eight overlayers, to react at the Rh surface; they decomposed at a probability promoted by the water overlayers. The production probabilities of H2, CO, CH2CH2 and CH4 continued to increase with co-adsorbed D2O*, up to two D2O overlayers, despite separate increasing rates; above two D2O overlayers, those of H2, CO and CH2CH2 were approximately saturated while that of CH4 decreased. The increased (or saturated) production probabilities are rationalized with an increased (saturated) concentration of surface hydroxyl (OD*, formed by O* abstracting D from D2O*), whose intermolecular hydrogen bonding with adsorbed ethanol facilitates proton transfer from ethanol to OD* and thus enhances the reaction probability. The decreasing behavior of CH4 could also involve the competition for H* with the formation of H2 and HDO.

13.
Org Lett ; 9(26): 5405-8, 2007 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-18031050

RESUMO

A non-equilibrating mixture of two aziridinium imides (AIs) resulting from the photoaddition of N-methyl-1,2,4-triazoline-3,5-dione and cycloheptene has been prepared. Warming the AIs produces only the product of the expected ene reaction with no back-reaction to starting materials. Even though one of the pair does not have the geometry necessary for hydrogen abstraction, both AIs disappear at essentially the same rate, showing that AIs cannot be the direct precursors of the ene product.

14.
ACS Appl Mater Interfaces ; 9(3): 2232-2239, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28004922

RESUMO

A nanocomposite layer comprising the conjugated polymer poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctyl)fluorene] (PFN) and nickel oxide (NiOx) has been employed as the hole transport layer (HTL) in organic photovoltaics (OPVs) featuring PBDTTBO-C8 and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the active layer. The optimal device incorporating the PFN:NiOx nanocomposite as the HTLs displayed a power conversion efficiency (PCE) to 6.2%, up from 4.5% for the corresponding device incorporating pristine NiOx as the HTL layer: a nearly 40% improvement in PCE. X-ray photoelectron spectroscopy (XPS) was used to determine the types of chemical bonding, ultraviolet photoelectron spectroscopy (UPS) to measure the change in work function, and atomic force microscopy (AFM) to examine the morphology of the composite layers. The growth of nickel trioxide, Ni2O3, in the PFN:NiOx layer played a key role in producing the p-doping effect and in tuning the work function, thereby improving the overall device performance.

15.
Clin Pharmacol Ther ; 71(5): 311-24, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12011817

RESUMO

OBJECTIVE: Our objective was to characterize the oxidative metabolism of estradiol by human term placenta and its modulation by cigarette smoking. METHODS: Placental microsomes were prepared from term placentas obtained from 13 cigarette smokers (20 to 30 cigarettes per day until the time of delivery) and 13 control subjects who were nonsmokers. Estrogen metabolism was studied by incubation of 250 nmol/L [(3)H]estradiol with placental microsomes and NADPH, and the estrogen metabolites were determined by HPLC and gas chromatography-mass spectrometry. RESULTS: 2-Hydroxyestradiol was the major hydroxyestrogen detected, followed by 6alpha-hydroxyestradiol. Small amounts of several other hydroxyestrogen metabolites (4-hydroxyestradiol, 6beta-hydroxyestradiol, 7alpha-hydroxyestradiol, and 16alpha-hydroxyestradiol) were also detected. Large amounts of estrone plus small amounts of 2-hydroxyestrone and unidentified nonpolar metabolites were formed. Cigarette smoking stimulated the placental hydroxylation of benzo[a ]pyrene by about 16-fold. Cigarette smoking had little or no effect on the overall rate of placental estradiol metabolism or on the formation of estrone, 2-hydroxyestradiol, 2-hydroxyestrone, or 16alpha-hydroxyestradiol. However, placental formation of 4-hydroxyestradiol and 7alpha-hydroxyestradiol was increased 38% (P =.08) and 150% (P =.05), respectively, in cigarette smokers. The formation of 6alpha-hydroxyestradiol was decreased 33% (P =.04). Metabolic formation of 15alpha-hydroxyestradiol was observed during incubations of estradiol with placental microsomes from 11 of the 13 cigarette smokers, but this metabolite was not detected during incubations with placental microsomes from any of the 13 nonsmokers. Analysis of data from all 26 placentas showed that the 15alpha-hydroxylation of estradiol was highly correlated with benzo[a ]pyrene hydroxylation (r = 0.93; P <.001). CONCLUSIONS: Many hydroxylated estradiol metabolites were formed by placental microsomes from cigarette smokers and nonsmokers. 15alpha-Hydroxylation of estradiol was markedly stimulated in the placentas of cigarette smokers.


Assuntos
Estradiol/análogos & derivados , Estradiol/metabolismo , Placenta/metabolismo , Fumar/metabolismo , Adulto , Estrogênios de Catecol , Feminino , Humanos , Hidroxilação , Microssomos/metabolismo , NADP/metabolismo , Placentação , Gravidez , Fumar/fisiopatologia
16.
Obstet Gynecol ; 99(3): 477-82, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11864677

RESUMO

OBJECTIVE: To evaluate whether abnormal umbilical cord insertion (UCI) into the placenta is a risk factor for birth weight discordancy in twin gestations. METHODS: Pathology records of all liveborn twins delivered between January 1993 and June 1996 were reviewed. The information collected included gestational age at delivery, birth weight, gross placental pathology, and placental UCI-velamentous, marginal, or disc. Discordancy in birth weight was defined as an intrapair difference of at least 20%. Analyses were stratified on placental chorionicity. Odds ratios and 95% confidence intervals for birth weight discordancy were calculated based on the presence of an abnormal (velamentous or marginal) placental UCI relative to normal (disc) UCI on both placentae, after adjusting for potential confounders. RESULTS: There were 447 twin pairs identified. Dichorionic diamniotic placentation was present in 358 pairs (80.1%), monochorionic diamniotic in 84 (18.8%), and monochorionic monoamniotic in five (1.1%). There was a 13-fold increase in the risk of birth weight discordancy in monochorionic diamniotic twins in the presence of a velamentous UCI (odds ratio 13.5, 95% confidence interval 1.4, 138.4), with a rate of birth weight discordancy of 46%. This relationship was not demonstrated in dichorionic diamniotic twins (odds ratio 1.0, 95% confidence interval 0.3, 3.5). CONCLUSION: Birth weight discordancy in twins is a different entity depending on chorionicity. The substantial increase in birth weight discordancy in monochorionic diamniotic twins that accompanies velamentous UCI underscores the need for prenatal detection and increased surveillance in these twins.


Assuntos
Peso ao Nascer , Placenta , Gravidez Múltipla , Gêmeos , Cordão Umbilical , Adulto , Córion , Feminino , Humanos , Recém-Nascido , Gravidez , Fatores de Risco , Ultrassonografia Pré-Natal
17.
J Phys Chem Lett ; 4(2): 310-6, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-26283440

RESUMO

To realize the origin of efficient spin injection at organic-ferromagnetic contact in organic spintronics, we have implemented the formation of quasi-molecular magnet via surface restructuring of a strong organic acceptor, tetrafluoro-tetracyano-quinodimethane (F4-TCNQ), in contact with ferromagnetic cobalt. Our results demonstrate a spin-polarized F4-TCNQ layer and a remarkably enhanced magnetic anisotropy of the Co film. The novel magnetic properties are contributed from strong magnetic coupling caused by the molecular restructuring that displays an angular anchoring conformation of CN and upwardly protruding fluorine atoms. We conclude that the π bonds of CN, instead of the lone-pair electrons of N atoms, contribute to the hybridization-induced magnetic coupling between CN and Co and generate a superior magnetic order on the surface.

18.
J Chin Med Assoc ; 76(3): 153-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23497968

RESUMO

BACKGROUND: Reciprocal translocation is the most common type of translocation; however, there are only a few studies that address the indications for reciprocal translocation in amniocentesis. Here we share our data, based on 30 years' experience in a single tertiary center, to investigate the rates and indications for amniocentesis in cases of reciprocal translocations. METHODS: A retrospective review of 16,749 pregnant women, who underwent midtrimester amniocentesis between January 1981 and December 2010, was conducted. Seventy-four cases of reciprocal translocation were identified. RESULTS: The percentage of reciprocal translocations in all amniocentesis cases was 0.44% (74/16,749); of these 74 cases, 56 were balanced and 18 unbalanced. De novo abnormality occurred in 23 cases, which constituted 31.1% of all reciprocal translocations. The three major indications for amniocentesis with a diagnosis of reciprocal translocation included advanced maternal age (AMA, 52.7%), a parent with an abnormal karyotype (17.6%), and abnormal biochemical markers in the maternal serum (12.2%). For individual types of reciprocal translocations (balanced and unbalanced), except for the presence of abnormal biochemical markers in maternal serum, both AMA and a parent with an abnormal karyotype were primary indications for amniocentesis. However, the highest percentage of reciprocal translocations in all amniocentesis cases was found in cases involving a parent with an abnormal karyotype (5.16%, 13/252). CONCLUSION: Patients with a parent who carries an abnormal karyotype should be encouraged to undergo amniocentesis in prenatal consultation, since the risk of a diagnosis of reciprocal translocation can be particularly high.


Assuntos
Amniocentese , Translocação Genética , Adulto , Feminino , Humanos , Cariótipo , Idade Materna , Gravidez , Estudos Retrospectivos
19.
J Chin Med Assoc ; 76(6): 335-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23612056

RESUMO

BACKGROUND: Advanced maternal age (AMA) is the most frequent indication for amniocentesis in predicting balanced reciprocal translocations, and abnormal ultrasound findings are indications in predicting unbalanced reciprocal translocations; however, to date, no studies have focused on Robertsonian translocations. METHODS: A retrospective review was conducted on 16,749 pregnant women who underwent midtrimester amniocentesis between January 1981 and December 2010. Robertsonian translocations were identified in 39 cases. RESULTS: The percentage of Robertsonian translocations in all amniocentesis cases was 0.23% (39/16,749); 31 were balanced and eight were unbalanced. De novo abnormality occurred in 17 cases, or in 43.6% of all Robertsonian translocations. The two major indications for amniocentesis with a diagnosis of Robertsonian translocations were AMA (41.0%, n = 16) and a parent with abnormal karyotypes (18.0%, n = 7). The highest percentage of Robertsonian translocations was found in parents with abnormal karyotypes (2.8%, 7/252), but neither of the indications were clearly superior for detecting de novo Robertsonian translocations. CONCLUSION: Although AMA is an indication for amniocentesis in approximately two-fifths of cases with Robertsonian translocations, the indication of parent with abnormal karyotypes was more likely to lead to the detection of non-de novo Robertsonian translocations, suggesting that parents with abnormal karyotypes need careful prenatal consultation.


Assuntos
Translocação Genética , Amniocentese , Feminino , Humanos , Cariótipo , Gravidez , Estudos Retrospectivos , Taiwan
20.
Taiwan J Obstet Gynecol ; 51(2): 206-11, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22795095

RESUMO

OBJECTIVE: Amniocentesis is a popular and effective prenatal diagnostic tool for chromosomal disorders. It is well-established that the risk of chromosomal abnormalities increases with maternal age; however, other related indications are seldom reported. Herein, we report our 30-year experience with amniocentesis from a single medical center, focusing on the indications and rates of abnormality. MATERIAL AND METHODS: A retrospective review of 16,749 pregnant women in the mid-trimester between January 1981 and December 2010 was conducted. The medical records were analyzed. RESULTS: The indications for amniocentesis were advanced maternal age (≥ 34 years old) (n=10,970, 65.5%), increasing-risk maternal triple-marker Down's screening test (≥ 1/270) (n=2090, 12.5%), history of abnormal offspring birth (n=792, 4.7%), abnormal ultrasound findings (n=484, 2.9%), parent with abnormal karyotype (n=252, 1.5%), family history of chromosomal abnormality (n=183, 1.1%), drug and radiation exposure (n=165), abnormal chorionic villus sampling (CVS) results (n=25), intrauterine fetal death (n=50), and other non-specific causes (n=1662, 9.9%). The rate of abnormality for each indication was 16% in the abnormal CVS group, 12% in the intrauterine fetal death group, 11.5% for parental chromosomal abnormality, 8.7% in the abnormal ultrasound finding group, 3.0% in the increasing-risk maternal triple-marker Down's screening test group, 2.5% in the advanced maternal age group, 1.5% for other non-specific causes, 1.4% for history of abnormal offspring birth, and 1.1% for family history of chromosomal abnormality. CONCLUSIONS: Both parents with abnormal karyotype and abnormal ultrasound findings are indications for which consideration of further amniocentesis is highly recommended.


Assuntos
Amniocentese , Aberrações Cromossômicas , Doenças Fetais/genética , Doenças Genéticas Inatas/genética , Amostra da Vilosidade Coriônica , Aberrações Cromossômicas/induzido quimicamente , Aberrações Cromossômicas/efeitos da radiação , Síndrome de Down/diagnóstico , Síndrome de Down/genética , Feminino , Morte Fetal/genética , Doenças Fetais/diagnóstico por imagem , Doenças Genéticas Inatas/diagnóstico por imagem , Humanos , Cariótipo , Idade Materna , Valor Preditivo dos Testes , Gravidez , Estudos Retrospectivos , Fatores de Risco , Taiwan , Ultrassonografia Pré-Natal
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