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1.
Plant Dis ; 108(3): 700-710, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37580883

RESUMO

Strawberry is a popular fruit with valuable nutrition and an attractive fragrance, but its production and propagation are limited by various diseases, including anthracnose and gray mold. For disease management, biological control measures are environmentally friendly and good alternatives to fungicides to avoid crop losses, reduce carbon emissions, and improve food safety. In this study, Paenibacillus polymyxa TP3, which originated from the strawberry phyllosphere, was shown to antagonize the anthracnose fungal pathogen Colletotrichum siamense and reduce leaf symptoms on strawberry plants. Several mass spectra corresponding to fusaricidin were detected in the confrontation assay of P. polymyxa TP3 and C. siamense by image mass spectrometry. The transcription of fusA and fusG in the fusaricidin biosynthesis gene cluster increased while P. polymyxa TP3 was cultured in the medium containing the culture filtrate of C. siamense, as detected by reverse-transcription polymerase chain reaction, indicating the involvement of fusaricidins in P. polymyxa TP3 antagonism against the anthracnose pathogen. Further disease control assays demonstrated the time frame and spatial mode of P. polymyxa TP3-induced systemic resistance of strawberry against C. siamense. The transcript level of the marker gene FaPDF1.2 of the jasmonic acid pathway increased in strawberry leaves after drenching treatment with P. polymyxa TP3, and the callose deposition was enhanced by further flg22 treatment. In addition, P. polymyxa TP3 treatments of the strawberry mother plants reduced C. siamense infection in the daughter plants, which would be a potent feature for the application of P. polymyxa TP3 in strawberry nurseries and fields to reduce the impact of diseases, especially anthracnose.


Assuntos
Fragaria , Fungicidas Industriais , Paenibacillus polymyxa , Fragmentos de Peptídeos , Timopoietinas , Paenibacillus polymyxa/genética , Fragaria/microbiologia , Fungicidas Industriais/farmacologia
2.
ACS Nano ; 17(24): 25037-25044, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38096421

RESUMO

Graphene possesses an exotic band structure that spans a wide range of important technological wavelength regimes for photodetection, all within a single material. Conventional methods aimed at enhancing detection efficiency often suffer from an extended response time when the light is switched off. The task of achieving ultrafast broad-band photodetection with a high gain remains challenging. Here, we propose a devised architecture that combines graphene with a photosensitizer composed of an alternating strip superstructure of WS2-WSe2. Upon illumination, n+-WS2 and p+-WSe2 strips create alternating electron- and hole-conduction channels in graphene, effectively overcoming the tradeoff between the responsivity and switch time. This configuration allows for achieving a responsivity of 1.7 × 107 mA/W, with an extrinsic response time of 3-4 µs. The inclusion of the superstructure booster enables photodetection across a wide range from the near-ultraviolet to mid-infrared regime and offers a distinctive photogating route for high responsivity and fast temporal response in the pursuit of broad-band detection.

3.
ACS Nano ; 17(11): 10181-10190, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37212535

RESUMO

Modern infrared (IR) microscopy, communication, and sensing systems demand control of the spectral characteristics and polarization states of light. Typically, these systems require the cascading of multiple filters, polarization optics, and rotating components to manipulate light, inevitably increasing their sizes and complexities. Here, we report two-terminal mid-infrared (mid-IR) emitters, in which tuning the polarity of the applied bias can switch their emission peak wavelengths and linear polarization states along two orthogonal orientations. Our devices are composed of two back-to-back p-n junctions formed by stacking anisotropic light-emitting materials, black phosphorus and black arsenic-phosphorus with MoS2. By controlling the crystallographic orientations and engineering the band profile of heterostructures, the emissions of two junctions exhibit distinct spectral ranges and polarization directions; more importantly, these two electroluminescence (EL) units can be independently activated, depending on the polarity of the applied bias. Furthermore, we show that when operating our emitter under the polarity-switched pulse mode, the time-averaged EL exhibits the characteristics of broad spectral coverage, encompassing the entire first mid-IR atmospheric window (λ: 3-5 µm), and electrically tunable spectral shapes.

4.
Micromachines (Basel) ; 14(2)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36838123

RESUMO

In this study, AlGaN/GaN light-emitting HEMTs (LE-HEMT) with a single quantum well inserted in different locations in the epitaxy layers are fabricated and analyzed. For both structures, light-emitting originated from electrons in the 2DEG and holes from the p-GaN for radiative recombination is located in the quantum well. To investigate the importance of the location of single quantum well, optical characteristics are compared by simulation and experimental results. The experimental results show that the main light-emitting wavelength is shifted from 365 nm in the UV range to 525 nm in the visible range when the radiative recombination is confined in the quantum well and dominates among other mechanisms. Epi B, which has a quantum well above the AlGaN barrier layer in contrast to Epi A which has a quantum well underneath the barrier, shows better intensity and uniformity in light-emitting. According to the simulation results showing the radiative distribution and electron concentrations for both structures, the lower quantum efficiency is due to the diverse current paths in Epi A. On the other hand, Epi B shows better quantum confinement and therefore better luminescence in the same bias condition, which is consistent with experimental observations. These findings are critical for advancing the performance of LE-HEMTs.

5.
ACS Appl Mater Interfaces ; 14(28): 32665-32674, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35797527

RESUMO

A bias-selectable photodetector, which can sense the wavelength of interest by tuning the polarity of applied bias, is useful for target discrimination and identification applications. So far, those detectors are generally based on the back-to-back photodiode configuration via exploiting epitaxial semiconductors as optoelectronic materials, which inevitably lead to high fabrication costs and complex device architectures. Here, we demonstrate that our band-engineered van der Waals heterostructures can be applied as bias-selectable photodetectors. Our first prototypical device is mainly composed of black phosphorus (BP) and MoTe2 light absorbers sandwiching a thin MoS2 hole blocking layer. By varying the bias polarity, its spectral photoresponse can be switched between near-infrared and short-wave infrared bands, and our optoelectronic characterizations indicate that the detector can exhibit high external quantum efficiency (EQE) and fast operation speed. With this framework, we further demonstrate the detector with bias-selectable photoresponses within the mid-wave infrared band using BP/MoS2/arsenic-doped BP heterostructures and show that our developed detectors can be integrated into a single-pixel imaging system to capture dual-band infrared imaging.

6.
Sci Rep ; 12(1): 7380, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513480

RESUMO

Recently, low-concentration atropine (0.01%) has gained increased attention in controlling myopia progression with satisfying effects and minimal side effects. However, studies concerning responders to 0.01% atropine are limited. This retrospective observational cohort study aimed to determine the responder characteristics of 0.01% atropine in Asian children. One hundred forty children (aged between 3 and 15 years) receiving 0.01% atropine were analyzed for the factors influencing annual spherical equivalent changes (SE). The mean age was 9.13 (2.6) years, the mean baseline SE was - 1.56 (1.52) diopters (D), and the mean annual SE change was - 0.52 (0.49) D. A 58.63% responder rate (146/249) of myopic control was achieved with 0.01% atropine in our entire cohort under the criteria of less than 0.5 D of myopic progression annually. The subjects were stratified into 4 subgroups based on a cut-off point of baseline SE of - 1.5 D and baseline age of 9 years. The responder rate differed significantly with the highest being the youngest with the lowest myopia subgroups. Our results demonstrated that children with myopia better than - 1.5 D and younger than 9 years had the highest potential to achieve successful myopic control under 0.01% atropine therapy.


Assuntos
Atropina , Miopia , Adolescente , Criança , Pré-Escolar , Progressão da Doença , Humanos , Midriáticos , Miopia/tratamento farmacológico , Soluções Oftálmicas/uso terapêutico , Refração Ocular , Estudos Retrospectivos
7.
Nat Nanotechnol ; 17(7): 721-728, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35501377

RESUMO

Electrical manipulation of the valley degree of freedom in transition metal dichalcogenides is central to developing valleytronics. Towards this end, ferromagnetic contacts, such as Ga(Mn)As and permalloy, have been exploited to inject spin-polarized carriers into transition metal dichalcogenides to realize valley-dependent polarization. However, these materials require either a high external magnetic field or complicated epitaxial growth steps, limiting their practical applications. Here we report van der Waals heterostructures based on a monolayer WSe2 and an Fe3GeTe2/hexagonal boron nitride ferromagnetic tunnelling contact that under a bias voltage can effectively inject spin-polarized holes into WSe2, leading to a population imbalance between ±K valleys, as confirmed by density functional theory calculations and helicity-dependent electroluminescence measurements. Under an external magnetic field, we observe that the helicity of electroluminescence flips its sign and exhibits a hysteresis loop in agreement with the magnetic hysteresis loop obtained from reflective magnetic circular dichroism characterizations on Fe3GeTe2. Our results could address key challenges of valleytronics and prove promising for van der Waals magnets for magneto-optoelectronics applications.

8.
ACS Appl Mater Interfaces ; 14(21): 24856-24863, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35476925

RESUMO

Extending the operation wavelength of silicon photonics to the mid-infrared (mid-IR) band will significantly benefit critical application areas, including health care, astronomy, and chemical sensing. However, a major hurdle for mid-IR silicon photonics has been the lack of high-speed, high-responsivity, and low noise-equivalent power (NEP) photodetectors. Here, we demonstrate a van der Waals (vdW) heterostructure mid-IR photodetector integrated on a silicon-on-insulator (SOI) waveguide. The detector is composed of vertically stacked black phosphorus (BP)/molybdenum ditelluride (MoTe2). We measured high responsivity (up to 0.85 A/W) over a 3-4 µm spectral range, indicating that waveguide-confined light could strongly interact with vdW heterostructures on top. In addition, the waveguide-integrated detector could be modulated at high speed (>10 MHz) and its switching performance shows excellent stability. These results, together with the noise analysis, indicate that the NEP of the detector is as low as 8.2 pW/Hz1/2. This reported critical missing piece in the silicon photonic toolbox will enable the wide-spread adoption of mid-IR integrated photonic circuits.

9.
Front Med (Lausanne) ; 9: 791068, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35280861

RESUMO

Purpose: Pediatric strabismus surgery has low success rates and high reoperation rates because of difficult alignment measurements and the nature of different strabismus types. Furthermore, adjustable sutures are not easily employed in children on an OPD basis. Methods: This was a retrospective comparative case study of children less than 12 years old who underwent strabismus surgery and were followed up at least 6 months postoperatively. We proposed a novel method that combines adjustable sutures and corneal light reflexes in regular strabismus surgery to improve surgical results. Efficacy and safety were evaluated and compared with those in a regular fixed-suture group. Results: In total, 128 children (88: exotropia and 41: esotropia) in the novel method group (Group 1) and 109 (71: exotropia and 38: esotropia) in the regular fixed-suture group (Group 2) were enrolled. The primary outcome was the immediate target angle (for esotropia within 4 PD of orthotropia and exotropia within 8 PD of esotropia within the first week postoperatively); the secondary outcome was success at the 6-month visit (angle of deviation < 10 PD). Consequently, there was a significantly higher proportion of achieving the immediate target range and success rate in both exotropic and esotropic patients in Group 1 than in Group 2. A significantly lower reoperation rate was also demonstrated in Group 1. No complications were noted in either group.Conclusions: The novel method enabled a higher proportion of subjects to achieve an immediate target range and success rate and a lower chance of reoperation among both esotropic and exotropic patients.

10.
J Microbiol Immunol Infect ; 55(5): 820-828, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34974992

RESUMO

BACKGROUND: Lower respiratory tract infection (LRTI) is one of the most fatal diseases for adults. Influenza is a well-recognized cause of severe pneumonia; however, the outcomes of LRTI caused by non-influenza respiratory viruses (NIRVs) have not been sufficiently investigated. This study aimed to describe the characteristics and outcomes of LRTI associated with respiratory viruses (RVs) in adults. MATERIALS/METHODS: A retrospective review was performed using medical records of adult patients whose lower respiratory tract (LRT) specimens (endotracheal aspirate and bronchoalveolar lavage fluid) tested positive for RVs using multiplex PCR. Underlying comorbidities, laboratory data, and clinical outcomes were analyzed. RESULTS: Among the 808 LRT specimens collected from 666 adult patients, RV was identified in 115 specimens (14%) from 106 patients (16%). The underlying comorbidities and laboratory data did not differ between patients with influenza- and NIRV-related LRTI. The 14-day and 30-day mortality rates were higher in the influenza group than in the NIRV group (24% versus 7%, p = 0.03 and 33% versus 13%, p = 0.02, respectively), whereas the 90-day mortality rate did not. In a multivariate Cox model to predict 90-day mortality, shock and acute kidney injury independently predicted a higher mortality rate (hazard ratio (HR): 4.28, 95% CI: 1.46-12.58, p = 0.01 and HR: 2.80, 95% CI: 1.28-6.15, p = 0.01, respectively), whereas the detection of influenza did not. CONCLUSIONS: Influenza and NIRVs were associated with increased mortality due to LRTI in adults. Therefore, NIRVs are among key pathogens causing LRTI and should not be neglected by clinicians.


Assuntos
Influenza Humana , Pneumonia , Infecções Respiratórias , Vírus , Adulto , Humanos , Infecções Respiratórias/etiologia , Vírus/genética , Sistema Respiratório , Pneumonia/complicações
11.
J Chin Med Assoc ; 84(2): 151-157, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33177406

RESUMO

BACKGROUND: Since December 2019, a number of cases and deaths due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic have been reported worldwide. In spite of clinical manifestations similar to the SARS-CoV epidemic in 2003, affected organs and severity are yet to be defined. Moreover, viral load alterations and viral shielding among different specimens remained scarce. Therefore, clarifying clinical presentations and correlations among viral loads, disease severity, and viral shielding of SARS-CoV-2 infection is crucial in the disease prevention. METHODS: The clinical courses of SARS-CoV-2 cases were presented through Gantt charts. Laboratory examinations and reverse-transcriptase quantitative polymerase chain reactions (RT-qPCR) among different specimens were tested periodically. Cycle thresholds (CT) were recorded and presented as viral loads. RESULTS: From March 2020 to April 2020, 4 SARS-CoV-2 cases were presented, of which, cases 1 and 2 manifested the symptoms severer than cases 3 and 4, along with higher serum lactate dehydrogenase levels and graded for lymphocytopenia. Case 4 initially exhibited anosmia but recovered within a short period. Curves of the CT of all the cases, except case 2, concaved upward after prescribing hydroxychloroquine (HCQ) and azithromycin. Except for case 4, the CT in most stool specimens remained undetectable; however, none of the cases presented gastrointestinal symptoms. Surprisingly, the CT values of the saliva specimens were inconsistent with those of the nasopharyngeal swabs and sputum. CONCLUSION: SARS-CoV-2 manifests various symptoms. Sudden onset of central nervous system symptoms should be considered. The timing of HCQ and azithromycin administration might be a key factor in the viral load reduction. Positive prediction values of RT-qPCR of different specimens should be tested carefully to prevent false-negative results.


Assuntos
COVID-19/complicações , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2 , Carga Viral , Adulto , Idoso , Azitromicina/administração & dosagem , COVID-19/virologia , Feminino , Humanos , Hidroxicloroquina/administração & dosagem , Hidroxicloroquina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Tratamento Farmacológico da COVID-19
12.
Nano Lett ; 20(9): 6824-6830, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32816495

RESUMO

Light-emitting diodes (LEDs) based on III-V/II-VI materials have delivered a compelling performance in the mid-infrared (mid-IR) region, which enabled wide-ranging applications in sensing, including environmental monitoring, defense, and medical diagnostics. Continued efforts are underway to realize on-chip sensors via heterogeneous integration of mid-IR emitters on a silicon photonic chip, but the uptake of such an approach is limited by the high costs and interfacial strains, associated with the processes of heterogeneous integrations. Here, the black phosphorus (BP)-based van der Waals (vdW) heterostructures are exploited as room-temperature LEDs. The demonstrated devices emit linearly polarized light, and the spectra cover the technologically important mid-IR atmospheric window. Additionally, the BP LEDs exhibit fast modulation speed and exceptional operation stability. The measured peak extrinsic quantum efficiency is comparable to the III-V/II-VI mid-IR LEDs. By leveraging the integrability of vdW heterostructures, we further demonstrate a silicon photonic waveguide-integrated BP LED.

13.
ACS Appl Mater Interfaces ; 12(1): 1201-1209, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31804794

RESUMO

Black phosphorus (BP), a narrow band gap semiconductor without out-of-plane dangling bonds, has shown promise for broadband and integrable photodetector applications. Simultaneously exhibiting high speed and high-efficiency operation, however, remains a critical challenge for current BP-based photodetectors. Here, we demonstrate a photodetector based on the BP-based van der Waals heterostructures. The developed photodetector enables broadband responses in the visible to mid-infrared range with external quantum efficiency ranging from 20 to 52% at room temperature. These results together with noise measurements indicate that the photodetector can detect light in the picowatt range. Furthermore, the demonstrated BP detector has ultrafast rise (1.8 ns) and fall (1.68 ns) times, and its photoresponse exhibits reproducible switching behavior even under consecutive and rapid light intensity modulations (2100 cycles, 200 MHz), as indicated by the eye-diagram measurement. By leveraging these features, we show our BP heterostructures can be configured as a point-like detector in a scanning confocal microscopy, useful for mid-infrared imaging applications.

14.
Am J Ophthalmol ; 157(4): 908-914.e1, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24384526

RESUMO

PURPOSE: To compare the effects of oblique astigmatism on refractive amblyopia in children aged 3-7 years with those having orthogonal astigmatism. DESIGN: A retrospective review of medical records. METHODS: The medical records of patients attending Tri-Service General Hospital in Taiwan from January 2003 to December 2010 were reviewed and summarized. Seventy-two children with oblique astigmatism-related refractive amblyopia (Group 1) and 82 children with orthogonal astigmatism (Group 2) were chosen. Characteristics such as baseline visual acuity (VA), the time course of VA improvement, refractive error, and family history were assessed. RESULTS: Group 1 showed a worse baseline mean VA (±SD) of 0.61 (0.13) vs 0.52 (0.16) logMAR (P = .01), a slower rate of amblyopia improvement, and higher prevalence of parental oblique astigmatism (29% vs 5.5%; P < .01) than did Group 2. The cylinder power of astigmatism (in D) causing amblyopia in Group 1 of 2.48 (0.82) was lower than that in Group 2: 2.93 (0.71) (P = .006). However, Group 1 achieved a noninferior resolution of amblyopia (mean final VA 0.18 vs 0.16 logMAR) after longer treatment of 6.45 (2.44) vs 5.86 (2.92) months (P = .039). CONCLUSIONS: A smaller degree of initial oblique astigmatism caused amblyopia than did orthogonal astigmatism. Although the children with oblique astigmatism achieved equal resolution rates after treatment, this took longer. Therefore, we should pay more attention to children with mild oblique astigmatism, as they are more likely to develop oblique astigmatism-related amblyopia. Moreover, early diagnosis and prompt treatment might help visual improvement.


Assuntos
Ambliopia/terapia , Astigmatismo/terapia , Hiperopia/fisiopatologia , Miopia/fisiopatologia , Ambliopia/fisiopatologia , Astigmatismo/fisiopatologia , Bandagens , Criança , Pré-Escolar , Óculos , Feminino , Humanos , Masculino , Estudos Retrospectivos , Privação Sensorial , Acuidade Visual/fisiologia
15.
Int J Ophthalmol ; 6(4): 487-91, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23991384

RESUMO

AIM: To evaluate the efficacy of a new modality for improving visual acuity (VA) in pediatric patients with anisometropic amblyopia. METHODS: Retrospective and interventional case series. Medical records of 360 children with anisometropic amblyopia treated with a modality that included rotated prisms, lenses, and near activities from January 2008 to January 2012 were analyzed. Characteristics such as improvement of VA and contrast sensitivity in amblyopic eyes and resolution of amblyopia (VA ≤0.1logMAR or a difference of ≤2 lines in logMAR between the eyes) were assessed. RESULTS: Among the patients, the mean VA of the amblyopic eyes improved from 0.48logMAR (SD=0.16) to 0.12logMAR (SD=0.16) and the mean VA improvement was 0.36logMAR (SD=0.10, P<0.001). Resolution of amblyopia was achieved in 233 of 360 patients (64.72%). The mean time for resolution of amblyopia was 8.05 weeks (SD=4.83) or 14.14 sessions (SD=8.76). Among the study group, refraction error did not change significantly after treatment (P=0.437). We found that better baseline VA may be related to success and shorten the time to amblyopic resolution. CONCLUSION: VA and contrast sensitivity improved with rotated prisms, correcting lenses, and near activities in children with anisometropic amblyopia. The VA improvement by this modality was comparable to other methods. However, the time to resolution of amblyopia was shorter with this method than with other modalities. Rotated prisms combined with near acuity could provide an alternative treatment in children with anisometropic amblyopia who can't tolerant traditional therapy method like patching.

16.
Am J Emerg Med ; 30(1): 256.e1-2, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21106320

RESUMO

A clinical feature of bilateral popliteal arterial dissection without involving the descending aorta, bilateral iliac, as well as femoral arteries has never been reported in the past literature. We report a 56-year-old man with hypertension and coronary artery disease who presented to our emergency department with complaints of bilateral knee pain after long-distance walking. Physical examination was notable for elevated blood pressure, but there was no palpable pulsation over dorsalis pedis arteries on his feet. Laboratory evaluation revealed a d-dimer level of 35.2 mg/L (FEU) on the day of the test and 1.2 mg/L one and a half months ago (normal level, <0.55). These findings were suggestive of a recent-onset peripheral arterial occlusive disorder. Computed tomography of the aorta showed bilateral popliteal arterial dissection with arterial intimal flap. Abdominal aorta, bilateral iliac, and femoral arteries remained intact with only arteriosclerotic change. Minimally invasive endovascular stent grafting was then performed. The patient had an uneventful recovery.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Artéria Poplítea , Angioplastia , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/cirurgia , Tomografia Computadorizada por Raios X
17.
Neurocrit Care ; 15(1): 175-81, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20198514

RESUMO

INTRODUCTION: We report the effective use of dexmedetomidine in the treatment of a patient with a history of chronic alcohol abuse and an acute traumatic brain injury who developed agitation that was unresolved if from traumatic brain injury, or alcohol withdrawal or the combination of both. Treatment with benzodiazepines failed; lorazepam therapy obscured our ability to do reliable neurological testing to follow his brain injury and nearly resulted in intubation of the patient secondary to respiratory suppression. Upon admission to hospital, the patient was first treated with intermittent, prophylactic doses of lorazepam for potential alcohol withdrawal based upon our institution's standard of care. His neurological examinations including a motor score of 6 (obeying commands) on his Glasgow Coma Scale testing, laboratory studies, and repeat CT head imaging remained stable. For lack of published literature in diagnosing symptoms of patients with a history of both alcohol withdrawal and traumatic brain injury, a diagnosis of agitation secondary to presumed alcohol withdrawal was made when the patient developed acute onset of tachycardia, confusion, and extreme anxiety with tremor and attempts to climb out of bed requiring him to be restrained. Additional lorazepam doses were administered following a hospital-approved protocol for titration of benzodiazepine therapy for alcohol withdrawal. The patient's mental status and respiratory function deteriorated with the frequent lorazepam dosing needed to control his agitation. Dexmedetomidine IV infusion at a rate of 0.5 mcg/kg/h was then administered and was titrated ultimately to 1.5 mcg/kg/h. After 8 days of therapy with dexmedetomidine, the patient was transferred from the ICU to a step-down unit with an intact neurological examination and no evidence of alcohol withdrawal. Airway intubation was avoided during the patient's entire hospitalization. This case report highlights the intricate balance between the side effects of benzodiazepine sedation for treatment of agitation and the difficulties of monitoring the neurological status of non-intubated patients with traumatic brain injury. CONCLUSION: Given the large numbers of alcohol-dependent patients who suffer a traumatic brain injury and subsequently develop agitation and alcohol withdrawal in hospital, dexmedetomidine offers a novel strategy to facilitate sedation without neurological or respiratory depression. As this case report demonstrates, dexmedetomidine is an emerging treatment option for agitation in patients who require reliable, serial neurological testing to monitor the course of their traumatic brain injury.


Assuntos
Lesões Encefálicas/psicologia , Dexmedetomidina/uso terapêutico , Hipnóticos e Sedativos/uso terapêutico , Agitação Psicomotora/tratamento farmacológico , Idoso , Alcoolismo/psicologia , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/terapia , Humanos , Masculino , Exame Neurológico , Agitação Psicomotora/etiologia
18.
Anesth Analg ; 109(4): 1273-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19762757

RESUMO

BACKGROUND: Our primary objective was to detect malignant hyperthermia (MH)-susceptible persons and thereby prevent MH episodes. We identified variants in the ryanodine receptor isoform 1 using molecular pedigree analysis. METHODS: Nineteen exons covering major hotspots were chosen for the primary screening by polymerase chain reaction, denaturing high performance liquid chromatography, and confirmed by direct sequencing. RESULTS: Three novel variants involving amino acid changes were identified in two unrelated families as Met2698Arg, Glu2724Lys in exon 51 and Leu2785Val in exon 53. CONCLUSIONS: Three novel ryanodine receptor isoform 1 variants located either near or within the central domain might predispose carriers to MH.


Assuntos
Anestesia/efeitos adversos , Hipertermia Maligna/etiologia , Mutação , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Éxons , Predisposição Genética para Doença , Humanos , Masculino , Hipertermia Maligna/etnologia , Hipertermia Maligna/genética , Linhagem , Fenótipo , Medição de Risco , Fatores de Risco , Taiwan
19.
Am J Ophthalmol ; 147(2): 357-63, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18930448

RESUMO

PURPOSE: To evaluate the improvement in visual acuity (VA) in children 3 to 7 years old with hypermetropic amblyopia after full or partial hypermetropic correction. DESIGN: Retrospective interventional case series. METHODS: Medical records of 182 children with hypermetropic amblyopia treated with partial or full hypermetropic correction from January 1, 2001 to July 31, 2007 were evaluated. Improvement in the VA of the amblyopic eye, changes in the power of glasses, and the reduction in hypermetropia were assessed. RESULTS: Ninety-three children underwent full hypermetropic correction and the mean VA of their amblyopic eyes improved by 0.46 logarithm of minimal angle of resolution (logMAR). Eighty-one children underwent partial hypermetropic correction and the mean VA of their amblyopic eyes improved by 0.48 logMAR. The reduction in hypermetropia was 0.44 diopters (D)/year and 0.43 D/year, respectively. Changes in glasses at four to eight weeks of follow-up were noted in 11 children receiving full correction, all of whom were older than 5 years. Ten children, aged 3 to 5 years, with hypermetropia of more than 3 D and receiving partial correction, required a change of glasses and most (seven children) had underdiagnosed accommodative esotropia. CONCLUSIONS: Both full correction and partial correction of hypermetropic errors improved the VA of 3 to 7-year-old children with hypermetropic amblyopia. The reduction in hypermetropia was similar after full and partial hypermetropic correction. However, for children older than 5 years, full correction should be undertaken with care because the accompanying blur at distance can hinder compliance. For younger children, especially with a high degree of hypermetropia, full correction might be required to avoid strabismus, which would cancel the effects of spectacle correction.


Assuntos
Ambliopia/terapia , Óculos , Hiperopia/terapia , Ambliopia/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Hiperopia/fisiopatologia , Masculino , Estudos Retrospectivos , Acuidade Visual/fisiologia
20.
Chang Gung Med J ; 31(4): 364-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18935794

RESUMO

BACKGROUND: Neuromuscular blocking agents (NMBAs) are widely used during the induction and maintenance of anesthesia. Postoperative residual curarization (PORC) following the use of NMBAs still occurs even though intermediate-acting NMBAs were used. Train-of-four (TOF) stimulation is used to quantify the degree of neuromuscular blockade. The TOF ratio of 0.7 in the adductor pollicis muscle was associated with normal respiratory function. Pharyngeal function returned to normal while the TOF ratio reached 0.9. The aim of this study was to survey the PORC in the post-anesthesia care unit (PACU). METHODS: In this observational study, 308 patients who received general anesthesia with NMBAs were enrolled. Residual curarization was evaluated using the TOF-Watch acceleromyograph upon arrival in the PACU. Three consecutive TOF stimulations were applied and recorded at 15-second intervals. Two thresholds of TOF ratios (0.9 and 0.7) were used to assess the presence of residual curarization. RESULTS: TOF ratios less than 0.7 and 0.9 were observed in 15 (5%), and 97 (31%) patients, respectively. The differences of the TOF ratios between the male and female patients were significant (p = 0.014). In terms of weight, the differences between the patients with ratios > 0.9 and < or = 0.9 were significant (p = 0.013). There were 67, 49, 15, and three patients who received reversal medication in the > 0.9 group, < or = 0.9 and > 0.7 group, and < or = 0.7 group, respectively. The differences of the TOF ratios between the patients who received and those who did not receive reversal medication were not significant (p = 0.91). CONCLUSION: PORC is still a clinical problem in the modern PACU. Objective neuromuscular monitoring needs to be performed to ensure patient safety.


Assuntos
Bloqueadores Neuromusculares/efeitos adversos , Paralisia/induzido quimicamente , Complicações Pós-Operatórias/induzido quimicamente , Adulto , Idoso , Período de Recuperação da Anestesia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
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