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1.
Br J Ophthalmol ; 2024 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-39461733

RESUMEN

AIM: The aim is to compare the efficacy and safety of three different weight-adjusted intravenous erythropoietin (EPO) doses in patients with indirect traumatic optic neuropathy (TON). METHODS: This study is a multicentre, randomised, parallel-group, double-blind, dose-finding trial on patients aged ≥7 years with a confirmed diagnosis of indirect TON in ≤3 weeks. The trial had a 3-day treatment period and a 3-month follow-up period. Patients were randomly allocated (1:1:1) to receive EPO at doses of 900 IU/kg (300 IU/kg/day), 1800 IU/kg (600 IU/kg/day) or 3600 IU/kg (600 IU/kg/day on presentation and then 1 month later) EPO. The changes in the best-corrected visual acuity (BCVA), colour vision and relative afferent pupillary defect (RAPD) were assessed. RESULTS: Out of 118 eligible patients, 95 were randomised and 93 (31 in each group) completed the follow-ups. Three groups were not different regarding baseline BCVA (p=0.66), colour vision (p=0.25) and RAPD (p=0.79). All three groups showed a significant improvement of BCVA and RAPD with no significant differences among the groups. Colour vision showed a significant improvement only in the group with 3600 IU/kg EPO (p=0.005), even though final colour vision was not significantly different between the groups (p=0.49). Initial vision of no light perception (OR=7.79 (95% CI: 2.98 to 20.36), p<0.001), older age (OR=4.76 (95% CI: 1.92 to 11.76), p<0.001), longer trauma-treatment interval (OR=2.72, 95% CI: 1.16 to 6.33, p=0.02) and posterior orbital fractures (OR=2.63 (95% CI: 1.13 to 6.13), p=0.02) led to a significantly worse visual recovery. CONCLUSION: Increasing dose of EPO in patients with TON did not result in a better BCVA, colour vision and RAPD improvement. TRIAL REGISTRATION NUMBER: NCT03308448.

2.
Curr Eye Res ; : 1-6, 2024 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-39466138

RESUMEN

PURPOSE: Fungal keratitis (FK) is a difficult condition to treat, particularly in underdeveloped nations. The study aimed to compare the in vitro activity of chlorhexidine (CHX) and seven antifungal agents against a collection of fungi recovered from FK patients. METHODS: Seventy-three fungi were collected from patients with FK included in study. The antifungal agents tested were fluconazole, voriconazole, posaconazole, miconazole, natamycin, amphotericin B, and caspofungin. The concentration range for CHX was 1-1024 µg/mL. Assessments of antifungal susceptibility were conducted using the EUCAST broth microdilution reference method. RESULTS: The findings demonstrated the beneficial in vitro inhibition of filamentous and yeast fungi by CHX. CHX demonstrated efficacy against Fusarium spp., Aspergillus spp., Candida spp., S. apiospermum and dematiceous fungi at concentrations of 4-64, 32-64, 4-32, 8, and 4-16 µg/mL respectively. The median MICs and MIC distributions of CHX showed no significant differences among the evaluated spp. (p > 0.05). The most effective antifungal drug was posaconazole, which was followed by voriconazole, caspofungin, and amphotericin B. CONCLUSION: In situations where access to a range of antifungal medications and microbiological facilities is limited, CHX should be further investigated as a potential treatment for FK. It might be able to treat the condition as an inexpensive topical treatment.

3.
4.
Int Ophthalmol ; 44(1): 396, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39327323

RESUMEN

BACKGROUND: We aimed to evaluate the retinal vascular changes in the superficial and deep retinal vascular networks in the fellow eye of patients with central retinal artery occlusion (CRAO) and compare them with controls using optical coherence tomography angiography (OCT-A). METHODS: In a cross-sectional study, 27 patients with CRAO and 189 normal controls were included. Ophthalmic examination and OCT-A images were performed on all participants. RESULTS: The total vascular density of the superficial capillary network in the 6-mm scan was significantly lower in the fellow eye of patients with CRAO than in the control group (p = 0.02). No significant difference was observed in the FAZ area of the affected eyes and their fellow eyes compared with the controls. Total vascular density at 300 microns around the fovea was lower in the fellow eye compared with the control group (p = 0.034). CONCLUSIONS: The retinal vascular network changes in the fellow eyes of patients with CRAO suggest that persistent microvascular changes may be present before the onset of CRAO. This finding indicates that such changes could serve as an early diagnostic window for systemic vascular changes before catastrophic vascular events occur.


Asunto(s)
Capilares , Angiografía con Fluoresceína , Fondo de Ojo , Oclusión de la Arteria Retiniana , Vasos Retinianos , Tomografía de Coherencia Óptica , Humanos , Oclusión de la Arteria Retiniana/diagnóstico , Oclusión de la Arteria Retiniana/fisiopatología , Estudios Transversales , Masculino , Tomografía de Coherencia Óptica/métodos , Femenino , Angiografía con Fluoresceína/métodos , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/patología , Persona de Mediana Edad , Capilares/patología , Capilares/diagnóstico por imagen , Anciano , Agudeza Visual , Adulto
5.
Avicenna J Phytomed ; 14(4): 505-519, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952776

RESUMEN

Objective: The objective of this study was to evaluate the effectiveness of Hibiscus sabdariffa L. extract (HS) as an adjunct to valsartan in the treatment of high blood pressure in patients with mild chronic kidney disease (CKD). Materials and Methods: This trial was conducted in Gorgan, Iran. Seventy-two participants with CKD and high blood pressure were randomly assigned to either the HS group, receiving a 350 mg pill every 12 hr for 90 days along with 40 mg of valsartan every 12 hr, or the control group (40 mg valsartan + 12.5 mg hydrochlorothiazide). The primary objective was to assess the improvement of hypertension, while secondary objectives included the evaluation of proteinuria, albuminuria, kidney function, lipid profile, and electrolyte levels. Molecular docking analysis was performed to examine the mechanisms of action of the isolated components of HS. Results: Out of 80 initial participants, 72 were included in the analysis. Both groups showed a significant reduction in blood pressure (p<0.001). The HS group demonstrated a statistically significant decrease in lipid profile (p<0.001). There were no statistically significant differences between the groups regarding the reduction of renal markers. Molecular docking analysis revealed that the compounds present in HS, particularly its anthocyanins and flavonoids, exhibited greater angiotensin-converting enzyme (ACE) inhibitory potential than hydrochlorothiazide in both domains. Moreover, the compounds met the criteria for drug likeness and Lipinski rules. Conclusion: Adjunctive therapy with HS showed promising results in reducing hypertension and improving lipid profile in patients with CKD.

6.
J Ophthalmic Inflamm Infect ; 14(1): 33, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008027

RESUMEN

BACKGROUND: Infectious keratitis is a serious ocular condition, which can lead to corneal scarring, vision loss, and even blindness. Pediatric infectious keratitis accounts for about 13% of all cases, although there is a lack of comprehensive data regarding keratitis in less than two years of age population group. This study was aimed to determine predisposing factors, clinical characteristics, microbial profile, and management of infectious keratitis in a population of children aged less than two years. MATERIALS AND METHODS: A retrospective study was carried out in a tertiary eye institute over a period of 18 years from July 2005 to December 2022. Collected data was analyzed for demographics, predisposing factors, clinical features, and treatment methods. RESULTS: Fifty-seven cases of keratitis were identified. Age of the patients ranged from 1 to 24 months (Median: 6, interquartile range: 2-10). Thirty cases were male (52.6%). Predisposing factors were identified in 39 cases (68.4%): consisting of prior ocular trauma (n = 15), previous intraocular surgery (n = 11), ocular surface disease (n = 10), nasolacrimal duct obstruction (n = 4), prematurity (n = 3), developmental delay (n = 2), TORCH infection (n = 1), and contact lens (n = 1). Corneal thinning was observed in 29 eyes (50.9%), which progressed to perforation in 13 eyes (22.8%). Three patients developed endophthalmitis (95% CI, 1.5-13.4%). Most eyes had negative smear (60.4%) and culture (59.6%) results. Pseudomonas aeruginosa was the most common microorganism (11 of 21). Candida albicans was isolated in one case. In vitro susceptibility results showed good coverage of the combined ceftazidime and vancomycin regimen (100%). Surgical procedures were carried out in 35 eyes (61.4%) and 15 eyes required tectonic procedures (26.3%). CONCLUSION: Despite good coverage of medical treatment over cultured isolates, surgical tectonic intervention was required in nearly a quarter of cases to resolve the corneal infection. This finding indicates the necessity of prompt patient referring, corneal sampling and initiation of the treatment.

7.
J Ophthalmic Inflamm Infect ; 14(1): 36, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080177

RESUMEN

PURPOSE: The Moraxella species is a very uncommon pathogen that leads to microbial keratitis (MK). This study aimed to evaluate the clinical features, predisposing factors, and outcomes of Moraxella keratitis in patients of a tertiary eye hospital. METHODS: This retrospective study was conducted from 2015 to 2022, on patients who were admitted with the diagnosis of Moraxella keratitis confirmed by positive culture in a referral eye hospital. Demographics, predisposing factors, best-corrected visual acuity (BCVA), and prognosis were assessed. RESULTS: A total of 106 individuals diagnosed with Moraxella keratitis, were analyzed. The mean age was 54.42 ± 19.43 years. The mean baseline BCVA of the patients was 2.28 ± 0.6 LogMAR, while this amount reached 1.49 ± 0.81 in the 6-month follow-up (P-value = 0.02). The mean BCVA in the six-month follow-up of the patients who needed surgical interventions was significantly lower than the patients who received only medical treatment (2.15 ± 0.65 vs. 1.29 ± 0.75 LogMAR, P-value = 0.02). Patients with diabetes and those without diabetes did not substantially vary in the prevalence of corneal perforation (P-value = 0.515). Three predisposing factors including corneal perforation (odds ratio = 19.27, P-value = 0.001), hypertension (HTN) (odds ratio = 3.62, P-value = 0.03), and older age (odds ratio = 1.03, P-value = 0.008) were significantly associated with more need for surgical interventions. CONCLUSION: In this cohort, poor prognosis necessitating surgical interventions in Moraxella keratitis was found to be associated with corneal perforation, HTN, and older age.

8.
Ocul Surf ; 34: 159-164, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39084255

RESUMEN

PURPOSE: To develop an artificial intelligence (AI) model to diagnose Acanthamoeba keratitis (AK) based on in vivo confocal microscopy (IVCM) images extracted from the Heidelberg Retinal Tomograph 3 (HRT 3). METHODS: This retrospective cohort study utilized HRT 3 IVCM images from patients who had received a culture-confirmed diagnosis of AK between 2013 and 2021 at Massachusetts Eye and Ear. Two cornea specialists independently labeled the images as AK or nonspecific finding (NSF) in a blind manner. Deep learning tasks were then conducted through Python and TensorFlow. Distinguishing between AK and NSF was designed as the task and completed through a devised convolutional neural network. RESULTS: A dataset of 3312 confocal images from 17 patients with a culture-confirmed diagnosis of AK was used in this study. The inter-rater agreement for identifying the presence or absence of AK in IVCM images was 84 %, corresponding to a total of 2782 images on which both observers agreed and which were included in the model. 1242 and 1265 images of AK and NSF, respectively, were utilized in the training and validation sets, and 173 and 102 images of AK and NSF, respectively, were utilized in the evaluation set. Our model had an accuracy, sensitivity, and specificity of 76 % each, and a precision of 78 %. CONCLUSIONS: We developed an HRT-based IVCM AI model for AK diagnosis utilizing culture-confirmed cases of AK. We achieved good accuracy in diagnosing AK and our model holds significant promise in the clinical application of AI in improving early AK diagnosis.

9.
Cornea ; 43(10): 1310-1318, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38984532

RESUMEN

PURPOSE: Clinical diagnosis of dry eye disease is based on a subjective Ocular Surface Disease Index questionnaire or various objective tests, however, these diagnostic methods have several limitations. METHODS: We conducted a comprehensive review of articles discussing various applications of artificial intelligence (AI) models in the diagnosis of the dry eye disease by searching PubMed, Web of Science, Scopus, and Google Scholar databases up to December 2022. We initially extracted 2838 articles, and after removing duplicates and applying inclusion and exclusion criteria based on title and abstract, we selected 47 eligible full-text articles. We ultimately selected 17 articles for the meta-analysis after applying inclusion and exclusion criteria on the full-text articles. We used the Standards for Reporting of Diagnostic Accuracy Studies to evaluate the quality of the methodologies used in the included studies. The performance criteria for measuring the effectiveness of AI models included area under the receiver operating characteristic curve, sensitivity, specificity, and accuracy. We calculated the pooled estimate of accuracy using the random-effects model. RESULTS: The meta-analysis showed that pooled estimate of accuracy was 91.91% (95% confidence interval: 87.46-95.49) for all studies. The mean (±SD) of area under the receiver operating characteristic curve, sensitivity, and specificity were 94.1 (±5.14), 89.58 (±6.13), and 92.62 (±6.61), respectively. CONCLUSIONS: This study revealed that AI models are more accurate in diagnosing dry eye disease based on some imaging modalities and suggested that AI models are promising in augmenting dry eye clinics to assist physicians in diagnosis of this ocular surface condition.


Asunto(s)
Inteligencia Artificial , Síndromes de Ojo Seco , Humanos , Técnicas de Diagnóstico Oftalmológico , Síndromes de Ojo Seco/diagnóstico , Curva ROC , Sensibilidad y Especificidad
10.
Ann Med Surg (Lond) ; 86(6): 3423-3431, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38846882

RESUMEN

Introduction: There has been increased interest in the use of Statins in total hip and knee arthroplasty (THA and TKA) patients to improve outcomes and reduce postoperative complications. This study was performed to systematically review the evidence on Statin use in total joint arthroplasty, specifically its benefits and complications. Methods: Adhering to the PRISMA guidelines, a systematic review of PubMed, Embase, Scopus, Web of Science, and the Cochrane database was performed to find studies reporting on the effects of Statin use on outcomes of THA and TKA. Two authors independently selected relevant papers to include. Results: A total of 18 papers were included in the final analysis. Most were retrospective studies, with heterogeneous patient selection and outcome measures. The evidence on the risks and benefits of Statin use on outcomes of total joint arthroplasty was very limited and heterogeneous. Studies were focusing on perioperative cardiac outcomes, clinical outcomes and complications, renal, pulmonary, and gastrointestinal outcomes. Due to the heterogeneity of reported data, a formal meta-analysis was not possible. Conclusions: There is some evidence in the literature suggesting that perioperative use of Statins, especially in Statin-naïve patients, may reduce cardiac (e.g. atrial fibrillation) and noncardiac (e.g. delirium) complications, while not increasing the risk of muscle or liver toxicity. The authors also found low levels of evidence that Statin use may reduce the long-term risk for revision surgery and osteolysis.

11.
JBJS Rev ; 12(6)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38889241

RESUMEN

BACKGROUND: Total joint arthroplasty (TJA) is often associated with significant blood loss, leading to complications such as acute anemia and increased risk of infection and mortality. Tranexamic acid (TXA), an antifibrinolytic agent, has been recognized for effectively reducing blood loss during TJA. This systematic review and network meta-analysis aims to evaluate the efficacy and safety of oral TXA compared with other administration routes in TJA. METHODS: Adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a comprehensive literature search was conducted across multiple databases, including PubMed, Scopus, Embase, and Web of Science, focusing on randomized clinical trials involving oral TXA in TJA. The studies were assessed for quality using the Cochrane risk assessment scale. Data synthesis involved network meta-analyses, comparing outcomes including hemoglobin drop, estimated blood loss (EBL), transfusion rate, and deep vein thrombosis (DVT) rate. RESULTS: Our comprehensive literature search incorporated 39 studies with 7,538 participants, focusing on 8 TXA administration methods in TJA. The combination of oral and intra-articular (oral + IA) TXA markedly reduced hemoglobin drop more effectively than oral, intravenous (IV), and IA alone, but the difference was not significant. Oral + IA TXA significantly reduced EBL more effectively than oral + IV, IA + IV, and oral, IV, and IA alone. Perioperative transfusion rates with oral + IA TXA was significantly lower than that of oral, IA, and IV alone. The DVT rate with oral + IA was significantly lower than that with all other routes, including oral + IV, IA + IV, and oral, IA, and IV alone. CONCLUSION: Oral TXA, particularly in combination with IA administration, demonstrates significantly higher efficacy in reducing blood loss and transfusion rates in TJA, with a safety profile comparable with that of other administration routes. The oral route, offering lower costs and simpler administration, emerges as a viable and preferable option in TJA procedures. LEVEL OF EVIDENCE: Level I. See Instructions for Authors for a complete description of levels of evidence.


Asunto(s)
Antifibrinolíticos , Artroplastia de Reemplazo , Pérdida de Sangre Quirúrgica , Ácido Tranexámico , Humanos , Administración Oral , Antifibrinolíticos/administración & dosificación , Artroplastia de Reemplazo/efectos adversos , Pérdida de Sangre Quirúrgica/prevención & control , Metaanálisis en Red , Ácido Tranexámico/administración & dosificación , Resultado del Tratamiento
12.
Ocul Immunol Inflamm ; : 1-12, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709200

RESUMEN

OBJECTIVE: To provide a comprehensive overview of predisposing factors and clinical-microbiological profile of neonatal corneal ulcer. METHODS: The literature search was undertaken in PubMed, SCOPUS, Embase, Web of Science, and Google Scholar databases on published papers from inception to May 31, 2023. The included articles were independently assessed for methodological quality using a Joanna Briggs Institute checklist. Weighted analysis was utilized, assigning a weight of one to each case report and a weight equivalent to the sample size for the case series/original studies. RESULT: We included 34 relevant case reports/series and one original study. Seventy-four neonates were enrolled with a boy-to-girl ratio of 1.3:1 and a median age of 17 days (1-27 days). Prematurity and neonatal intensive care unit (NICU) care (21.6%), congenital horizontal tarsal kink (13.5%), neonatal herpes infection (13.5%), congenital entropion (5.4%), and jaundice (5.4%) were the most common potential risk factors and coexisting conditions. Microbiology evaluation showed positive results in 53.8% (21/39 cases). Viral and bacterial infections were the most common cause, followed by fungal infections. Herpes virus (18.9%), Pseudomonas aeruginosa (18.9%%) and Staphylococcus epidermidis (6.7%) were the most prevalent causative agents. Negative microbiology was significantly more common in neonates with structural abnormalities (14.9%) compared to others (6.8%) (p = 0.01). CONCLUSION: Based on the findings of reported studies, this systematic review has increased awareness of the risk factors and etiologies that lead to developing corneal ulcers in neonates.

13.
Int Ophthalmol ; 44(1): 230, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38805103

RESUMEN

PURPOSE: The present study aimed to epidemiologically evaluate patients with infectious keratitis following corneal transplantation. METHODS: This retrospective study analyzed medical records of patients who underwent keratoplasty from March 2014 to March 2022 at a tertiary center. A total of seventy-five patients were evaluated. The data were classified based on culture results, the type of microorganisms involved, treatment requirements, and the type of primary keratoplasty performed. RESULTS: Seventy-five patients were evaluated in this study, with a mean age of 45.9 years (22-95 years). The mean duration between the first surgery and the incidence of infectious keratitis was 1.43 years, and most cases occurred in the first year (56.2%). Bacterial and fungal keratitis in 2.17%, 1.39%, and 1.26% of cases undergoing penetrating keratoplasty (PK), endothelial keratoplasty (EK), and anterior lamellar keratoplasty (ALK) occurred, respectively. Streptococcus viridans (9.3%) and Staphylococcus aureus (6.6%) had the highest prevalence. Across various smear and culture results (gram-positive, gram-negative, fungal, and negative culture), no significant differences were found in endophthalmitis rates (P = 0.797) and the necessity for tectonic grafts (P = 0.790). Similarly, the choice of surgical method (PK, ALK, EK) showed no significant impact on the need for tectonic grafts (P = 0.45) or the rate of endophthalmitis (P = 0.55). CONCLUSIONS: The incidence of keratitis after a corneal graft was 1.7%, with Streptococcus viridans and Staphylococcus aureus the most common microorganisms. The rate of endophthalmitis associated with post-keratoplasty keratitis was 0.053%. There was no correlation between the necessity for a tectonic graft or the incidence of endophthalmitis and the type of microorganisms involved.


Asunto(s)
Trasplante de Córnea , Infecciones Bacterianas del Ojo , Infecciones Fúngicas del Ojo , Queratitis , Centros de Atención Terciaria , Humanos , Estudios Retrospectivos , Persona de Mediana Edad , Femenino , Masculino , Adulto , Anciano , Infecciones Bacterianas del Ojo/epidemiología , Infecciones Bacterianas del Ojo/microbiología , Infecciones Bacterianas del Ojo/etiología , Infecciones Bacterianas del Ojo/diagnóstico , Centros de Atención Terciaria/estadística & datos numéricos , Adulto Joven , Anciano de 80 o más Años , Incidencia , Queratitis/epidemiología , Queratitis/microbiología , Queratitis/diagnóstico , Queratitis/etiología , Trasplante de Córnea/efectos adversos , Infecciones Fúngicas del Ojo/epidemiología , Infecciones Fúngicas del Ojo/microbiología , Infecciones Fúngicas del Ojo/diagnóstico , Infecciones Fúngicas del Ojo/etiología , Bacterias/aislamiento & purificación , Complicaciones Posoperatorias/epidemiología
14.
Arch Bone Jt Surg ; 12(4): 245-255, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716177

RESUMEN

Objectives: This study aimed to introduce a novel arthroscopic treatment for medial and posteromedial instability of the knee and present the primary and follow-up results. Methods: All patients who underwent the arthroscopic approach to treat medial and posteromedial corner instability from 2007 to 2017 were included in this report. Overall, 45 patients were included, among which 75.6% were male. The mean age of patients was 32.2 ± 8.4 years. Overall, 44.4% and 15.6% of patients had associated meniscal injuries and chondral lesions, respectively. The mean follow-up duration of patients was 84.2 ± 25.3 months. Results: Overall, 37 patients developed a full range of motion (82.2%), and most patients (95.6%) showed excellent quadriceps strength (grades 4 and 5). All patients had a normal or 1+ posterior drawer test, Pivot shift test, and Lachman test on physical examination. Moreover, 60% had an associated isolated anterior cruciate ligament injury, 17.8% had an isolated posterior collateral ligament injury, and 17.6% had a combination of more than one ligament injury. One patient developed septic arthritis. Two patients experienced pain, and one pain patient developed pain with a bony spur formation in the medial epicondyle. Three patients showed a 2+ medial collateral ligament (MCL) test (moderate instability) at the final follow-up, all of whom had multi-ligament injuries. All patients, except the three patients who had a failed MCL reconstruction, returned to their previous activities. Conclusion: This study described a novel arthroscopic treatment of MCL injury, and the results showed acceptable postoperative and clinical outcomes. As the use of minimally invasive surgery may minimize multiple complications associated with open surgery, it is suggested that further studies be conducted regarding this approach when faced with patients who have MCL injuries requiring surgery.

15.
Sci Rep ; 14(1): 11156, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750121

RESUMEN

In recent years, there has been notable advancement in programmable metasurfaces, primarily attributed to their cost-effectiveness and capacity to manipulate electromagnetic (EM) waves. Nevertheless, a significant limitation of numerous available metasurfaces is their capability to influence wavefronts only in reflection mode or transmission mode, thus catering to only half of the spatial coverage. To the best of our knowledge and for the first time, a novel graphene-assisted reprogrammable metasurface that offers the unprecedented capability to independently and concurrently manipulate EM waves within both half-spaces has been introduced in the THz frequency band. This intelligent programmable metasurface achieves wavefront control in reflection mode, transmission mode, and the concurrent reflection-transmission mode, all within the same polarization and frequency channel. The meta-atom is constructed with two graphene sections, enabling straightforward modification of wave behavior by adjusting the chemical potential distribution within each graphene segment via an external electronic source. The proposed functionalities encompass various programmable modes, including single and dual beam control in reflection mode, dual beam control in transmission mode, simultaneous control of dual beams in reflection mode-direct transmission, and vice versa, and control of beam steering in reflection mode-dual beams in transmission mode simultaneously. The proposed metasurface is expected to be reprogrammable due to wavefront manipulation in both half-spaces separately and continuously for various applications such as imaging systems, encryption, miniaturized systems, and next-generation wireless intelligent communications.

16.
Sci Rep ; 14(1): 11155, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750175

RESUMEN

Wave-based cryptography, at the vanguard of advancing technologies in advanced information science, is essential for establishing a diverse array of secure cryptographic platforms. The realization of these platforms hinges on the intelligent application of multiplexing techniques, seamlessly combined with appropriate metasurface technology. Nevertheless, existing multi-channel encryption technologies based on metasurfaces face challenges related to information leakage during partial channel decoding processes. In this paper, we present a reprogrammable metasurface for polarization modulation. This metasurface not only allows for the arbitrary customization of linearly polarized reflected waves but also enables real-time amplitude modulation. Here, relying on polarization amplitude control, a fully secure communication protocol is developed precisely in the terahertz (THz) spectrum to achieve real-time information encryption based on polarization modulation metasurfaces where access to information is highly restricted. The proposed metasurface employs the double random phase encryption (DRPE) algorithm for information encryption. It transmits the encrypted data through different polarization channels using two graphene nanoribbons, exclusively controlled by external biasing conditions. Various encryption scenarios have been outlined to fortify information protection against potential eavesdroppers. The simulated results show that this unique technology for hiding images by manipulating the polarization of the reflected wave provides new opportunities for various applications, including encryption, THz communications, THz secure data storage, and imaging.

17.
J Arthroplasty ; 39(10): 2645-2660.e19, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38759817

RESUMEN

BACKGROUND: Developmental dysplasia of the hip (DDH) is one of the principal causes of secondary hip osteoarthritis, giving rise to considerable pain, impaired mobility, and a reduced quality of life. The optimal approach to managing individuals who have Crowe type IV DDH remains controversial. This study aimed to review the existing literature on the application of total hip arthroplasty (THA) as a treatment modality for Crowe type IV DDH, assessing its efficacy in addressing this severe hip deformity. METHODS: A comprehensive search across the PubMed, Scopus, and Web of Science databases identified relevant studies. Inclusion criteria encompassed investigations reporting outcomes of THA in Crowe type IV DDH patients. Data extraction and quality assessment were performed independently by 2 reviewers. Utilizing R software, the prevalence of THA complications was analyzed through proportion analysis, employing the inverse variance method. RESULTS: In this systematic review, a total of 74 studies were included, comprising a collective sample size of 2,829 patients (3,356 hips) diagnosed with Crowe type IV DDH. The posterior or posterolateral approach was the most commonly utilized surgical approach, followed by the lateral Hardinge and direct lateral approaches. The majority of studies have employed subtrochanteric osteotomies. Notably, post-THA, leg length discrepancy decreased, Trendelenburg sign resolved, and back pain was reduced. Patient-reported outcome measures like the Harris Hip Score improved significantly. The pooled prevalence rates of major postoperative complications were also assessed, including dislocation (7.2%), revision (8.7%), intraoperative fractures (10.5%), loosening (5.7%), nerve paralysis (5.6%), deep vein thrombosis (3.6%), infection (3.8%), heterotopic ossification grade 2 and above (6.1%), and a complicated patient rate of 11.0%. CONCLUSIONS: Synthesizing diverse study data, an overview of THAs performance emerges, demonstrating significant enhancements in function, pain reduction, quality of life, and the correction of substantial leg length discrepancy. While THA has shown positive outcomes, instances of complications have been reported. The decision to undergo THA should involve a collaborative assessment between the surgeon and the patient, considering potential benefits and complications.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Displasia del Desarrollo de la Cadera , Humanos , Displasia del Desarrollo de la Cadera/cirugía , Calidad de Vida , Resultado del Tratamiento , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Osteoartritis de la Cadera/cirugía , Osteoartritis de la Cadera/etiología , Osteotomía/métodos , Osteotomía/efectos adversos , Diferencia de Longitud de las Piernas/etiología , Diferencia de Longitud de las Piernas/cirugía , Femenino
19.
Biosensors (Basel) ; 14(3)2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38534234

RESUMEN

Ultrasound A-scan is an important tool for quantitative assessment of ocular lesions. However, its usability is limited by the difficulty of accurately localizing the ultrasound probe to a lesion of interest. In this study, a transparent LiNbO3 single crystal ultrasound transducer was fabricated, and integrated with a widefield fundus camera to guide the ultrasound local position. The electrical impedance, phase spectrum, pulse-echo performance, and optical transmission spectrum of the ultrasound transducer were validated. The novel fundus camera-guided ultrasound probe was tested for in vivo measurement of rat eyes. Anterior and posterior segments of the rat eye could be unambiguously differentiated with the fundus photography-guided ultrasound measurement. A model eye was also used to verify the imaging performance of the prototype device in the human eye. The prototype shows the potential of being used in the clinic to accurately measure the thickness and echogenicity of ocular lesions in vivo.


Asunto(s)
Angiografía con Fluoresceína , Ratas , Animales , Humanos , Angiografía con Fluoresceína/métodos , Ultrasonografía
20.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38473976

RESUMEN

Extracellular vesicles (EVs), a diverse group of cell-derived exocytosed particles, are pivotal in mediating intercellular communication due to their ability to selectively transfer biomolecules to specific cell types. EVs, composed of proteins, nucleic acids, and lipids, are taken up by cells to affect a variety of signaling cascades. Research in the field has primarily focused on stem cell-derived EVs, with a particular focus on mesenchymal stem cells, for their potential therapeutic benefits. Recently, tissue-specific EVs or cell type-specific extracellular vesicles (CTS-EVs), have garnered attention for their unique biogenesis and molecular composition because they enable highly targeted cell-specific communication. Various studies have outlined the roles that CTS-EVs play in the signaling for physiological function and the maintenance of homeostasis, including immune modulation, tissue regeneration, and organ development. These properties are also exploited for disease propagation, such as in cancer, neurological disorders, infectious diseases, autoimmune conditions, and more. The insights gained from analyzing CTS-EVs in different biological roles not only enhance our understanding of intercellular signaling and disease pathogenesis but also open new avenues for innovative diagnostic biomarkers and therapeutic targets for a wide spectrum of medical conditions. This review comprehensively outlines the current understanding of CTS-EV origins, function within normal physiology, and implications in diseased states.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , Neoplasias , Humanos , Vesículas Extracelulares/metabolismo , Neoplasias/metabolismo , Células Madre/metabolismo , Células Madre Mesenquimatosas/metabolismo , Comunicación Celular/fisiología
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