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1.
Artigo em Inglês | MEDLINE | ID: mdl-38722780

RESUMO

PURPOSE: The effectiveness of facial exercise therapy in facial nerve palsy is well documented in the literature. However, there is no study examining its effect on ophthalmic manifestations of facial nerve palsy. The study reports its impact on the ophthalmic manifestations of facial nerve palsy using the ophthalmic-specific CADS grading system. METHODS: A retrospective case series of patients aged 18 years or older with facial nerve palsy was performed in a single specialist center between 2013 and 2019. Inclusion criteria were ophthalmic involvement, recorded CADS, and Sunnybrook grading scale pre- and post-treatment. RESULTS: A total of 73 patients were identified. There were 24 patients (M = 11, F = 13) who received facial exercise therapy only (group 1) and 49 patients (M = 17, F = 32) who received combined treatment of facial exercise therapy and eyelid surgery (group 2). The mean ages were 54.8 and 49.7 years, respectively. The groups were further subdivided into early (<3 months), intermediate (3-12 months), and late presenters (>12 months). In group 1, statistically significant improvements were seen in early (static asymmetry and dynamic function), intermediate (cornea), and late groups (cornea, static asymmetry, and dynamic function). The Sunnybrook grading scale was unable to detect changes in the ophthalmic features post-therapy or to report the corneal status. CONCLUSIONS: Facial exercise therapy is likely to improve ophthalmic manifestations of facial nerve palsy, in particular, those with static asymmetry and dynamic function of eye closure. The CADS grading scale is more suitable for the ophthalmic assessment.

2.
Hippocampus ; 33(4): 412-423, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36811254

RESUMO

Immature dentate granule cells (DGCs) generated in the hippocampus during adulthood are believed to play a unique role in dentate gyrus (DG) function. Although immature DGCs have hyperexcitable membrane properties in vitro, the consequences of this hyperexcitability in vivo remain unclear. In particular, the relationship between experiences that activate the DG, such as exploration of a novel environment (NE), and downstream molecular processes that modify DG circuitry in response to cellular activation is unknown in this cell population. We first performed quantification of immediate early gene (IEG) proteins in immature (5-week-old) and mature (13-week-old) DGCs from mice exposed to a NE. Paradoxically, we observed lower IEG protein expression in hyperexcitable immature DGCs. We then isolated nuclei from active and inactive immature DGCs and performed single-nuclei RNA-Sequencing. Compared to mature nuclei collected from the same animal, immature DGC nuclei showed less activity-induced transcriptional change, even though they were classified as active based on expression of ARC protein. These results demonstrate that the coupling of spatial exploration, cellular activation, and transcriptional change differs between immature and mature DGCs, with blunted activity-induced changes in immature cells.


Assuntos
Giro Denteado , Neurônios , Camundongos , Animais , Giro Denteado/fisiologia , Neurônios/fisiologia , Hipocampo , Neurogênese/fisiologia
3.
Ophthalmic Plast Reconstr Surg ; 39(5): 506-511, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37450622

RESUMO

PURPOSE: To describe a surgical technique that can achieve significant lower eyelid elevation in severe retraction in children using a pericranial periosteal flap with skin graft. METHODS: A retrospective, single-center, case series of 3 consecutive pediatric cases are performed where a pericranial periosteal flap was used with a skin graft to manage severe lower eyelid retraction. Outcome measures include the extent of lower eyelid elevation (mm) and complications in the follow-up visits. RESULTS: Three children with severe lower eyelid retraction underwent the surgery. There were 2 boys and 1 girl with the mean age of 6.7 years (range, 5-8 years). The improvement of lower eyelid retraction was 3, 3, and 7 mm at 28, 24, and 6 months, respectively. No perioperative or postoperative complications occurred. CONCLUSIONS: Children with severe lower eyelid retraction often have a complex craniofacial and surgical history, and its surgical correction can be challenging. This case series present the successful use of pericranial flaps in treating severe lower eyelid retraction in children. The authors recommend this flap in children where traditional options have either failed or are not applicable.


Assuntos
Blefaroplastia , Doenças Palpebrais , Masculino , Feminino , Humanos , Criança , Blefaroplastia/métodos , Estudos Retrospectivos , Doenças Palpebrais/cirurgia , Doenças Palpebrais/etiologia , Retalhos Cirúrgicos , Pálpebras/cirurgia
4.
Ophthalmic Plast Reconstr Surg ; 39(5): e155-e158, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37195826

RESUMO

A 26-year-old female presented with left enophthalmos following orbital floor and medial wall fracture despite surgical repair. She underwent further exploration and surgical repair but the enophthalmos persisted at 3-4 mm. Following discussion, she received 2 ml of hyaluronic acid filler injection into the posterior orbit and intraconal space. There were no immediate postoperative complications with normal optic nerve function, and the enophthalmos improved by 2 mm. The optic nerve function remained normal at the 4-week review. She returned 30 months following the injection with left periorbital edema, subjective red desaturation, and reduced peripheral visual field. On examination, there was a left relative afferent pupillary defect, disc pallor, and reduced visual field defect on automated visual field test. Following transcutaneous orbital injection of hyaluronidase, there was a subjective improvement in red desaturation with an improved peripheral visual field. Here the authors present a case of compressive optic neuropathy of delayed onset following orbital hyaluronic acid filler injection.


Assuntos
Enoftalmia , Doenças do Nervo Óptico , Feminino , Humanos , Adulto , Hialuronoglucosaminidase , Ácido Hialurônico/efeitos adversos , Doenças do Nervo Óptico/diagnóstico , Nervo Óptico , Órbita/cirurgia
5.
Opt Express ; 30(12): 20278-20287, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36224777

RESUMO

In this paper, we propose a novel beam shaping technique based on orbital angular momentum (OAM) modes for indoor optical wireless communications (OWC). Furthermore, we investigate two spatial diversity techniques, namely repetition-coding (RC) and Alamouti-type orthogonal space-time-block-coding (STBC) for indoor OWC employing the new beam shaping technique. The performance of both diversity schemes is systematically analyzed and compared under different beam shaping techniques using different OAM modes with different power ratios of the modes. It is shown that both RC and STBC can improve the system performance and effective coverage and RC outperforms STBC in all the beam shaping techniques regardless of the power ratios of the different modes. In addition, to further understand the performance of RC and STBC schemes against the signal delays induced during OAM mode conversion, the system tolerance of the two schemes to the delay interval is investigated with different OAM mode-based beam shaping techniques. Numerical results show that higher resistance to the delay interval can be achieved in STBC scheme. The advantage is more obvious when employing OAM0 and OAM1 based beam shaping technique.

6.
Vox Sang ; 117(2): 251-258, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34309031

RESUMO

BACKGROUND AND OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic raised concerns about the vulnerability of platelet supply and the uncertain impact of the resumption of elective surgery on utilization. We report the impact of COVID-19 on platelet supply and utilization across a large, integrated healthcare system in the Canadian province of British Columbia (BC). MATERIALS AND METHODS: Historical platelet use in BC by indication was compiled for fiscal year 2010/2011-2019/2020. Platelet collections, initial daily inventory and disposition data were assessed pre-COVID-19 (1 April 2018-15 March 2020) and for two COVID-19 time periods in BC: a shutdown phase with elective surgeries halted (16 March-17 May, 2020) and a renewal phase when elective surgeries resumed (18 May-27 September 2020); comparisons were made provincially and for individual health authorities. RESULTS: Historically, elective surgeries accounted for 10% of platelets transfused in BC. Initial daily supplier inventory increased from baseline during both COVID-19 periods (93/90 units vs. 75 units pre-COVID-19). During the shutdown phase, platelet utilization decreased 10.4% (41 units/week; p < 0.0001), and remained significantly decreased during the ensuing renewal period. Decreased platelet utilization was attributed to fewer transfusions during the shutdown phase followed by a decreased discard/expiry rate during the renewal phase compared to pre-COVID-19 (15.2% vs. 18.9% pre-COVID-19; p < 0.0001). Differences in COVID-19 platelet utilization patterns were noted between health authorities. CONCLUSION: Decreased platelet utilization was observed in BC compared to pre-COVID-19, likely due to a transient reduction in elective surgery as well as practice and policy changes triggered by pandemic concerns.


Assuntos
COVID-19 , Plaquetas , Colúmbia Britânica , Procedimentos Cirúrgicos Eletivos , Humanos , SARS-CoV-2
7.
Sensors (Basel) ; 22(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36433606

RESUMO

Line-of-sight (LOS) indoor optical wireless communications (OWC) enable a high data rate transmission while potentially suffering from optical channel obstructions. Additional LOS links using diversity techniques can tackle the received signal performance degradation, where channel gains often differ in multiple LOS channels. In this paper, a novel active transmitter detection scheme in spatial modulation (SM) is proposed to be incorporated with signal space diversity (SSD) technique to enable an increased OWC system throughput with an improved bit-error-rate (BER). This transmitter detection scheme is composed of a signal pre-distortion technique at the transmitter and a power-based statistical detection method at the receiver, which can address the problem of power-based transmitter detection in SM using carrierless amplitude and phase modulation waveforms with numerous signal levels. Experimental results show that, with the proposed transmitter detection scheme, SSD can be effectively provided with ~0.61 dB signal-to-noise-ratio (SNR) improvement. Additionally, an improved data rate ~7.5 Gbit/s is expected due to effective transmitter detection in SM. The SSD performances at different constellation rotation angles and under different channel gain distributions are also investigated, respectively. The proposed scheme provides a practical solution to implement power-based SM and thus aids the SSD realization for improving system performance.

8.
Clin Infect Dis ; 69(10): 1757-1763, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30980715

RESUMO

INTRODUCTION: Autologous hematopoietic stem cell transplantation (AHSCT) with anti-thymocyte globulin (ATG) conditioning as treatment of active multiple sclerosis (MS) is rapidly increasing across Europe (EBMT registry data 2017). Clinically significant Epstein-Barr virus reactivation (EBV-R) following AHSCT with ATG for severe autoimmune conditions is an underrecognized complication relative to T-cell deplete transplants performed for hematological diseases. This retrospective study reports EBV-R associated significant clinical sequelae in MS patients undergoing AHSCT with rabbit ATG. METHODS: Retrospective data were analyzed for 36 consecutive MS-AHSCT patients at Kings College Hospital, London. All patients routinely underwent weekly EBV DNA polymerase chain reaction monitoring and serum electrophoresis for monoclonal gammopathy (MG or M-protein). EBV-R with rising Epstein-Barr viral load, M-protein, and associated clinical sequelae were captured from clinical records. RESULTS: All patients had evidence of rising EBV DNA-emia, including 7 who were lost to long-term follow-up, with a number of them developing high EBV viral load and associated lymphoproliferative disorder (LPD). Nearly 72% (n = 18/29) developed de novo MG, some with significant neurological consequences with high M-protein and EBV-R. Six patients required anti-CD20 therapy (rituximab) with complete resolution of EBV related symptoms. Receiver operating characteristics estimated a peak EBV viremia of >500 000 DNA copies/mL correlated with high sensitivity (85.5%) and specificity (82.5%) (area under the curve: 0.87; P = .004) in predicting EBV-R related significant clinical events. CONCLUSION: Symptomatic EBV reactivation increases risk of neurological sequelae and LPD in MS-AHSCT. We recommend regular monitoring for EBV and serum electrophoresis for MG in MS patients in the first 3 months post-AHSCT.


Assuntos
Soro Antilinfocitário/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 4/fisiologia , Esclerose Múltipla/terapia , Paraproteinemias/etiologia , Condicionamento Pré-Transplante/efeitos adversos , Ativação Viral , Adulto , Animais , Soro Antilinfocitário/imunologia , DNA Viral/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coelhos/imunologia , Estudos Retrospectivos , Transplante Autólogo , Carga Viral
9.
BMC Ophthalmol ; 19(1): 5, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30616677

RESUMO

BACKGROUND: It has been previously reported that one copy of the variable number tandem repeat (VNTR) B alleles of the GPIbα gene increases the risk of non-arteritic ischaemic optic neuropathy (NAION) and the second eye involvement. This is the first case where the presence of both alleles is associated with bilateral NAION. CASE PRESENTATION: A 52-year-old male presented with loss of vision in one eye and was diagnosed with NAION. The following year, he suffered another attack of NAION in the fellow eye. Genetic testing showed that he had both copies of VNTR B alleles of the GPIbα gene. CONCLUSIONS: We report a case of bilateral NAION in the presence of two copies of VNTR B alleles of the GPIbα gene. This may have further implications for the function of platelet glycoproteins.


Assuntos
Neuropatia Óptica Isquêmica/genética , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Alelos , Humanos , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites
10.
Opt Lett ; 43(17): 4236-4239, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30160760

RESUMO

We propose and experimentally demonstrate a non-orthogonal multiple access (NOMA) enabled 60 GHz radio-over-fiber (RoF) fronthaul system with coordinated base stations, improving the data rate and coverage of 60 GHz RoF systems. First, coordinated multipoint transmission using space-time block coding (STBC) is adopted in fronthaul, achieving 1.3 dB improvement in receiver sensitivity compared to two fronthaul links' transmission without STBC. Second, multi-cell coordination in RoF fronthaul is presented, where a multi-level code (MLC)-based NOMA scheme is employed. A sum rate of 6 Gbps for three users is achieved along 10 km fronthaul transmission and 1.24 m wireless transmission. The experimental results show that the valid power allocation ratio range improves from 3.5≤R≤4.2 in conventional superposition code-based NOMA fronthaul to 3≤R≤5 in our proposed coordinated MLC-NOMA fronthaul link.

11.
Opt Lett ; 43(13): 3132-3135, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29957797

RESUMO

Beam-steering-based optical wireless technologies are being widely investigated due to the capability of providing high-speed wireless connectivity in indoor applications. However, high-speed indoor optical wireless systems are traditionally realized with discrete bulky components, significantly limiting their practical applications. In this Letter, we demonstrate an infrared optical wireless communication system employing a miniaturized silicon integrated photonic circuit for beam steering for the first time. Experimental results show that up to 12.5 Gb/s optical wireless communication can be achieved with error-free performance over a free-space range of 140 cm, and limited mobility of users can be realized. The experimental results of this Letter open the way for realizing integrated high-speed optical wireless communications.

12.
Opt Express ; 25(18): 22046-22054, 2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-29041494

RESUMO

In this paper, we report a novel mechanism to simultaneously provide secure connections for multiple users in indoor optical wireless communication systems by employing the time-slot coding scheme together with chaotic phase sequence. The chaotic phase sequence is generated according to the logistic map and applied to each symbol to secure the transmission. Proof-of-concept experiments are carried out for multiple system capacities based on both 4-QAM and 16-QAM modulation formats, i.e. 1.25 Gb/s, 2 Gb/s and 2.5 Gb/s for 4-QAM, and 2.5 Gb/s, 3.33 Gb/s and 4 Gb/s for 16-QAM. Experimental results show that in all cases the added chaotic phase does not degrade the legitimate user's signal quality while the illegal user cannot detect the signal without the key.

13.
Opt Express ; 25(19): 22923-22931, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-29041598

RESUMO

The indoor user localization function is in high demand for high-speed wireless communications, navigations and smart-home applications. The optical wireless technology has been used to localize end users in indoor environments. However, its accuracy is typically very limited, due to the ambient light, which is relatively strong. In this paper, a novel high-localization-accuracy optical wireless based indoor localization system, based on the use of the mechanism that estimates background light intensity, is proposed. Both theoretical studies and demonstration experiments are carried out. Experimental results show that the accuracy of the proposed optical wireless indoor localization system is independent on the localization light strength, and that an average localization error as small as 2.5 cm is attained, which is 80% better than the accuracy of previously reported optical wireless indoor localization systems.

14.
Opt Lett ; 41(22): 5166-5169, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27842084

RESUMO

This letter proposes what we believe is a novel time-slot coding (TSC) scheme to provide optical wireless communications to multiple users simultaneously with limited multiuser interference. We studied the proposed TSC experimentally and our results show that the code alignment tolerance, due to imperfect timing during the code generation process in practice, is 90.2%, 91.8%, and 93.1% with 4-QAM modulation at the received optical power of -22 dBm, -20 dBm, and -18 dBm, respectively. Furthermore, we also demonstrated a proof-of-concept experiment for simultaneous wireless connectivity for up to five users at multiple gross data rates (0.5 Gbps, 1 Gb/s, 1.6 Gb/s, 2 Gb/s, and 2.5 Gb/s).

15.
Opt Lett ; 40(7): 1246-9, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25831304

RESUMO

In this Letter, we propose a novel indoor localization system based on optical wireless technology. By using the same architecture as the high-speed full-duplex indoor optical wireless communication system, the "search and scan" process, and the added transmission power and beam footprint information in the "search and scan" message, indoor localization functionality is achieved. Proof-of-concept experiments are carried out, and results show that an average error of <15 cm is achieved with a localization beam size of 1 m. In addition, the major localization-accuracy-limiting factors are analyzed both theoretically and experimentally. When incorporated with the optical wireless communication system, high-speed indoor wireless personal area networks can be achieved.

16.
Opt Lett ; 39(19): 5717-20, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25360967

RESUMO

In this Letter, we propose and experimentally demonstrate a free-space based reconfigurable card-to-card optical interconnect architecture with 16-carrierless-amplitude-phase modulation. Experimental results show that up to 120 Gb/s (3×40 Gb/s) flexible interconnection can be achieved for up to 30 cm distance with a worst-case receiver sensitivity of -9.70 dBm.

17.
Nanotechnology ; 25(20): 205101, 2014 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-24784034

RESUMO

Single-walled carbon nanotubes (SWNTs) are promising heating agents in cancer photothermal therapy when under near infrared radiation, yet few efforts have been focused on the quantitative understanding of the photothermal energy conversion in biological systems. In this article, a mesoscopic study that takes into account SWNT morphologies (diameter and aspect ratio) and dispersions (orientation and concentration), as well as thermal boundary resistance, is performed by means of an off-lattice Monte Carlo simulation. Results indicate that SWNTs with orientation perpendicular to the laser, smaller diameter and better dispersion have higher heating efficiency in cancer photothermal therapy. Thermal boundary resistances greatly inhibit thermal energy transfer away from SWNTs, thereby affecting their heating efficiency. Through appropriate interfacial modification around SWNTs, compared to the surrounding healthy tissue, a higher temperature of the cancer cell can be achieved, resulting in more effective cancer photothermal therapy. These findings promise to bridge the gap between macroscopic and microscopic computational studies of cancer photothermal therapy.


Assuntos
Simulação por Computador , Hipertermia Induzida , Raios Infravermelhos/uso terapêutico , Nanotubos de Carbono , Neoplasias/terapia , Fototerapia , Humanos , Método de Monte Carlo
18.
Sci Rep ; 14(1): 2391, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287040

RESUMO

Advanced molecular and cellular technologies provide promising tools for wildlife and biodiversity conservation. Induced pluripotent stem cell (iPSC) technology offers an easily accessible and infinite source of pluripotent stem cells, and have been derived from many threatened wildlife species. This paper describes the first successful integration-free reprogramming of adult somatic cells to iPSCs, and their differentiation, from three endangered Southeast Asian primates: the Celebes Crested Macaque (Macaca nigra), the Lar Gibbon (Hylobates lar), and the Siamang (Symphalangus syndactylus). iPSCs were also generated from the Proboscis Monkey (Nasalis larvatus). Differences in mechanisms could elicit new discoveries regarding primate evolution and development. iPSCs from endangered species provides a safety net in conservation efforts and allows for sustainable sampling for research and conservation, all while providing a platform for the development of further in vitro models of disease.


Assuntos
Células-Tronco Pluripotentes Induzidas , Primatas , Animais , Animais Selvagens , Diferenciação Celular , Reprogramação Celular , Espécies em Perigo de Extinção , Hylobates , Macaca
19.
Nat Biotechnol ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418648

RESUMO

Astrocytes, the most abundant glial cell type in the brain, are underrepresented in traditional cortical organoid models due to the delayed onset of cortical gliogenesis. Here we introduce a new glia-enriched cortical organoid model that exhibits accelerated astrogliogenesis. We demonstrated that induction of a gliogenic switch in a subset of progenitors enabled the rapid derivation of astroglial cells, which account for 25-31% of the cell population within 8-10 weeks of differentiation. Intracerebral transplantation of these organoids reliably generated a diverse repertoire of cortical neurons and anatomical subclasses of human astrocytes. Spatial transcriptome profiling identified layer-specific expression patterns among distinct subclasses of astrocytes within organoid transplants. Using an in vivo acute neuroinflammation model, we identified a subpopulation of astrocytes that rapidly activates pro-inflammatory pathways upon cytokine stimulation. Additionally, we demonstrated that CD38 signaling has a crucial role in mediating metabolic and mitochondrial stress in reactive astrocytes. This model provides a robust platform for investigating human astrocyte function.

20.
Cell Rep ; 43(2): 113774, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38349791

RESUMO

Long interspersed nuclear element-1 (L1 or LINE-1) is a highly abundant mobile genetic element in both humans and mice, comprising almost 20% of each genome. L1s are silenced by several mechanisms, as their uncontrolled expression has the potential to induce genomic instability. However, L1s are paradoxically expressed at high levels in differentiating neural progenitor cells. Using in vitro and in vivo techniques to modulate L1 expression, we report that L1s play a critical role in both human and mouse brain development by regulating the rate of neural differentiation in a reverse-transcription-independent manner.


Assuntos
Instabilidade Genômica , Células-Tronco Neurais , Humanos , Animais , Camundongos , Diferenciação Celular , Elementos Nucleotídeos Longos e Dispersos
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