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In recent years, intracranial aneurysms have been widely treated with endovascular methods. The anterior communicating artery (Acom) is the most common site of intracranial aneurysms. Despite its effectiveness, endovascular interventions can be associated with various intra-procedural and post-procedural complications. A systematic review of the literature was performed through PubMed, Embase, Scopus, and Web of Sciences databases up to March 18, 2022. The pooled rates of intra-procedural complications, mortality, procedure-related morbidities, the immediate and late aneurysm occlusion, and also the necessity for retreatment were calculated by applying random-effects models. A total of 41 articles with 4583 patients were included in the meta-analysis. The pooled rate of overall intra-procedural complications was 9.6% (95% CI: 7.7 to 11.8%). The initial rupture status and also type of EVT procedure did not affect the overall complication rate. The pooled rate of intra-procedural thrombosis, aneurysm rupture, coil prolapse, and early aneurysm rebleeding were 6.1% (95% CI: 4.5 to 8.2%); 4.2% (95% CI: 3.4 to 5.2%), 4.7% (95% CI: 3.2 to 6.7%), and 2.2% (95% CI: 1.5 to 3.2%), respectively. Our analysis showed that intra-procedural mortality occurred in 1.7% (95% CI: 1.1 to 2.5%) and procedure-related permanent morbidities in 3.3% (95% CI: 2.3 to 4.7%) of patients. Endovascular methods achieved complete and near to complete aneurysm occlusion (Raymond-Roy occlusion classification 1 and 2) in 89.2% (95% CI: 86.4 to 92.5%) of cases post-procedure, and 9.5% (95% CI: 7.3 to 12.4%) of patients needed retreatment due to recanalization in follow-ups. Endovascular treatment can serve as an acceptable method for Acom aneurysms. However, improved endovascular treatment equipment and new techniques provide more satisfactory outcomes for complicated cases.
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Aneurisma Roto , Embolización Terapéutica , Procedimientos Endovasculares , Aneurisma Intracraneal , Aneurisma Roto/etiología , Embolización Terapéutica/métodos , Procedimientos Endovasculares/métodos , Humanos , Aneurisma Intracraneal/terapia , Retratamiento , Estudios Retrospectivos , Stents , Resultado del TratamientoRESUMEN
In this paper, a closed-form analytical solution of hyperbolic Pennes bioheat equation is obtained for spatial evolution of temperature distributions during moving laser thermotherapy of the skin and kidney tissues. The three-dimensional cubic homogeneous perfused biological tissue is adopted as a media and the Gaussian distributed function in surface and exponentially distributed in depth is used for modeling of laser moving heat source. The solution procedure is Eigen value method which leads to a closed form solution. The effect of moving velocity, perfusion rate, laser intensity, absorption and scattering coefficients, and thermal relaxation time on temperature profiles and tissue thermal damage are investigated. Results are illustrated that the moving velocity and the perfusion rate of the tissues are the main important parameters in produced temperatures under moving heat source. The higher perfusion rate of kidney compared with skin may lead to lower induced temperature amplitude in moving path of laser due to the convective role of the perfusion term. Furthermore, the analytical solution can be a powerful tool for analysis and optimization of practical treatment in the clinical setting and laser procedure therapeutic applications and can be used for verification of other numerical heating models.
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Hipertermia Inducida , Rayos Láser , Neoplasias/terapia , Temperatura , Calor , Humanos , Riñón/diagnóstico por imagen , Perfusión , Piel , Factores de TiempoRESUMEN
In time harmonic analysis, media composed of sub-wavelength metallic or dielectric inclusions are described by complex and dispersive effective constitutive parameters. A study of such parameters based on the conservation law of energy and causality is presented. We derive a set of general constraints on the real and imaginary parts of the constitutive parameters for lossy and lossless media in terms of electric and magnetic loss tangents. It is shown that a passive medium can indeed have a negative imaginary part of either the permeability or permittivity over a range of frequencies. These findings are consistent with the principles of causality and energy conservation.
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Reflection is usually a detrimental phenomenon in many applications such as flat-panel-displays, solar cells, photodetectors, infrared sensors, and lenses. Thus far, to control and suppress the reflection from a substrate, numerous techniques including dielectric interference coatings, surface texturing, adiabatic index matching, and scattering from plasmonic nanoparticles have been investigated. A new technique is demonstrated to manage and suppress reflection from lossless and lossy substrates. It provides a wider flexibility in design versus previous methods. Reflection from a surface can be suppressed over a narrowband, wideband, or multiband frequency range. The antireflection can be dependent or independent of the incident wave polarization. Moreover, antireflection at a very wide incidence angle can be attained. The reflection from a substrate is controlled by a buried nanoantenna array, a structure composed of (1) a subwavelength metallic array and (2) a dielectric cover layer referred to as a superstrate. The material properties and thickness of the superstrate and nanoantennas' geometry and periodicity control the phase and intensity of the wave circulating inside the superstrate cavity. A minimum reflectance of 0.02% is achieved in various experiments in the mid-infrared from a silicon substrate. The design can be integrated in straightforward way in optical devices. The proposed structure is a versatile AR coating to optically impedance matches any substrate to free space in selected any narrow and broadband spectral response across the entire visible and infrared spectrum.
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Nanopartículas/química , Nanoestructuras/química , Dispositivos Ópticos , Silicio/química , Luz , Óptica y Fotónica , Propiedades de SuperficieRESUMEN
Importance: Seizures have been reported as an adverse effect of the SARS-CoV-2 vaccine. However, no study has answered the question of whether there is any association between seizures in the general population and COVID-19 vaccination. Objective: To evaluate the seizure incidence among SARS-CoV-2 vaccine recipients compared with those who received a placebo. Data Sources: A systematic search of MEDLINE (via PubMed), Web of Science, Scopus, Cochrane Library, Google Scholar, review publications, editorials, letters to editors, and conference papers, along with the references of the included studies from December 2019 to July 7, 2023. Study Selection: Randomized clinical trials (RCTs) reporting seizure incidence with SARS-CoV-2 vaccination were included. Data Extraction and Synthesis: This study is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework and used the Mantel-Haenszel method with random- and common-effect models. The risk of bias of the studies was assessed using the Cochrane assessment tool for RCTs. Main Outcomes and Measures: The outcome of interest was new-onset seizure incidence proportion compared among (1) SARS-CoV-2 vaccine recipients and (2) placebo recipients. Results: Six RCTs were included in the study. Results of the pooled analysis comparing the incidence of new-onset seizure between the 63â¯521 vaccine and 54â¯919 placebo recipients in the 28-day follow-up after vaccine/placebo injection showed no statistically significant difference between the 2 groups (9 events [0.014%] in vaccine and 1 event [0.002%] in placebo recipients; odds ratio [OR], 2.70; 95% CI, 0.76-9.57; P = .12; I2 = 0%, τ2 = 0, Cochran Q P = .74). Likewise, in the entire blinded-phase period after injection, with a median of more than 43 days, no significant difference was identified between the vaccine and placebo groups regarding incident new-onset seizure (13/43â¯724 events [0.03%] in vaccine and 5/40â¯612 [0.012%] in placebo recipients; OR, 2.31; 95% CI, 0.86-6.23, P = .10, I2 = 0%, τ2 = 0, Cochran Q P = .95). Conclusions and Relevance: According to this systematic review and meta-analysis, there was no statistically significant difference in the risk of new-onset seizure incidence between vaccinated individuals and placebo recipients.
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Vacunas contra la COVID-19 , Ensayos Clínicos Controlados Aleatorios como Asunto , Convulsiones , Humanos , Vacunas contra la COVID-19/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , COVID-19/prevención & control , COVID-19/epidemiología , IncidenciaRESUMEN
The present study was carried out by focusing on the interaction between molecular complexes crown and thiacrown ethers such as 15-crown-5 (15C5), thia-15-crown-5 (T15C5), dithia-15-crown-5 (DT15C5) with homogeneous and heterogeneous dihalogens (XY) such as I2, IBr, ICl, Br2, Cl2 in the gas phase and in dichloromethane solvent through applying density function theory (DFT) as well as Gaussian 98 programs series. Characteristics such as frequency, enthalpy of reaction and energy have been totally specified. Special attention was placed on the study of electronegativity of outer halogen atom and polarization of bond between two halogens on the interaction. Results indicate that electronegativity of the external halogen atom and the polarization of dihalogen bond have remarkable effects on structure parameters, donor-acceptor effect, structural stabilization, and the enthalpy of the complex product. It is concluded that the charge transfer takes place in three complexes: 15C5, T15C5, and DT15C5; and the direction of charge transfer is from crown and thiacrown molecule to dihalogen. Stability of 15C5, T15C5 and DT15C5 complexes according to the energy is ICl > IBr > I2. The optimum condition for maximum stability of the molecular complex M IY is optimized plane structure and the optimum level of polarization of dihalogen during complexation of 15C5, T15C5, and DT15C5 is ICl molecule. The study of the interaction in dichloromethane solvent has similar results to the gas phase. An analysis of the NBO confirms the obtained results.
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Éteres Corona/química , Halógenos/química , Teoría Cuántica , Conformación Molecular , TermodinámicaRESUMEN
While TAVI is widely used, optimal medical therapy to reduce the mortality rate after transcatheter aortic valve implantation (TAVI) is still unclear. We performed a systematic review and meta-analysis to evaluate the impact of statins on mortality following TAVI. Present systematic review of the literature was performed using Medline, Embase, Scopus, and Web of Science; all studies reported all-cause mortality in patients who underwent TAVI and received or did not receive statin therapy. Data were analyzed using random-effects models. Seventeen articles (21 380 patients) were included in the meta-analysis. Statin therapy was associated with a reduction of all-cause mortality (Hazard ratio [HR] = .78, 95% Confidence interval [CI] .68-.89, P < .001). Moderate between-study heterogeneity was observed (I2 = 45.2). High-intensity statin therapy was more effective than low or moderate intensity statin therapy in reduction of all-cause mortality (Risk ratio [RR] = .62, 95% CI 0.45-.85, P = .003, I2 = .0). Statin therapy could reduce the mid-term all-cause mortality rate following TAVI. However, all included studies were observational and, therefore, randomized controlled trials are still needed to assess the effect of statin therapy on mortality after TAVI.
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Estenosis de la Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Resultado del Tratamiento , Factores de RiesgoRESUMEN
Introduction: Several scoring systems have been proposed to predict the outcomes of patients with ischemic heart disease. Global Registry of Acute Coronary Events (GRACE) and History, ECG, Age, Risk Factors, and Troponin (HEART) scores are two of the more widely used risk prediction tools in patients with acute coronary syndrome (ACS). The present systematic review and meta-analysis aimed to compare the value of GRACE and HEART scores in the outcome prediction of ACS patient. Method: The online databases of Medline, Embase, Web of Science, and Scopus were search until September 2022 for articles directly comparing GRACE and HEART scores value in prediction of outcome in patients with ACS. GRACE score cut-offs were categorized into two groups of less than and equal to 100 and more than 100, and HEART score cut-offs were categorized into three groups of less than 4, equal to 4, and more than 4. Investigated outcomes were major adverse cardiovascular events (MACE), acute myocardial infraction (AMI) and all-cause mortality. Results: 25 articles were included. The sensitivity and specificity of the GRACE score for prediction of MACE were 0.96 and 0.26 for cut-offs of ≤ 100, and 0.58 and 0.69 for cut-offs of >100, respectively. The sensitivity and specificity of the HEART score for prediction of MACE were 0.99 and 0.16 for cut-offs less than 4, 0.93 and 0.47 for equal to 4, and 0.77 and 0.78 for cut-offs greater than 4. GRACE score was shown to be predictive of AMI with sensitivity and specificity of 0.95 and 0.29, respectively. The analysis for the value of HEART score in the prediction of AMI a sensitivity and specificity of 0.94 and 0.48, respectively. The risk scores were not found to be suitable predictors of all-cause mortality. Conclusion: The results demonstrated the low specificity of GRACE and HEART scores in predicting the MACE, AMI and all-cause mortality, irrespective of the utilized cut-off. Considering the acceptable sensitivity of two scores in predicting the MACE and AMI, these scores were more suitable to be used as a rule-out tool for identification of ACS patients with low risk of developing adverse outcomes.
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Adjusting the exact warfarin dose has always been challenging since it has a narrow therapeutic window. Numerous factors, including poor drug compliance, drug-drug interactions, and malabsorption syndromes, affect the warfarin plasma concentration, leading to oversensitivity or resistance to warfarin. Patients who need more than 15 mg/d of warfarin for maintained anticoagulant effects are considered warfarin resistant. We describe a 62-year-old man referred to our center with bruising on his feet in June 2021. The patient had a history of valve replacement (mechanical prosthetic valves in 2013), hypothyroidism, and atrial fibrillation. He presented with warfarin resistance (first noticed in 2013) and did not reach the desired warfarin therapeutic effect despite receiving 60 mg of warfarin daily. Upon admission, the patient was on warfarin (100 mg/d) with an international normalized ratio (INR) of 1.5. He underwent laboratory and molecular genetic tests, which showed no mutation in the CYP2C9 and VKORC1, the genes associated with warfarin resistance. A stepwise diagnosis is required to identify the underlying cause. Assessing the patient's compliance, drug history, dietary habits, malabsorption diseases, and genetics may be necessary. We evaluated these possible reasons for resistance and found no correlation. The patient's warfarin intake was monitored closely to reach the INR therapeutic target of 3-3.5. He decided to leave the hospital with personal consent. He was discharged with a cardiologist referral and 24 warfarin tablets daily (120 mg/d) with an INR of 1.8. The patient was followed up 6 months and 2 years after discharge and was on the same daily dose of warfarin as at discharge, with no complications.
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The mechanical drilling process is a typical step in treating bone fractures to fix broken parts with screws and plates. Drilling generates a significant amount of heat and elevates the temperature of the bone, which can cause thermal osteonecrosis and damage to the surrounding bone tissue and nerves. Thermal inertia between heat flux and temperature gradient in nonhomogeneous interior structural medium-like biological tissues is arguable. Therefore, this paper proposes an analytical model of heat propagation in bone drilling for orthopedic surgery based on the hyperbolic Pennes bioheat transfer equation (HPBTE). Drilling experiments in bovine cortical bone samples were also carried out using an infrared thermography approach to confirm the proposed analytical model. Around the drilled hole surface, thermal necrosis is spread out from 1 to 10 mm. Increased feed rate reduces necrosis penetration distance and increases intense bone necrosis. The HPBTE includes thermal relaxation time effect and internal convective function of tissue perfusion rate. As these factors are not considered in the parabolic heat transfer equation (PHTE), the results show that the HPBTE is more accurate in predicting temperature and thermal osteonecrosis than the PHTE. As a result, proposed analytical model is a handy tool for calculating temperature to avoid thermal damage while improving process efficiency. Furthermore, it has the capability of controlling the manual or robotic drilling procedure for minimally invasive operations.
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Huesos/cirugía , Fracturas Óseas/cirugía , Calor , Procedimientos Ortopédicos/métodos , Ortopedia , Osteonecrosis , Animales , Huesos/lesiones , Bovinos , Humanos , Osteonecrosis/etiología , Osteonecrosis/cirugíaRESUMEN
Bone grinding is used to remove the skull bone and access tumors through the nasal passage during cranial base neurosurgery. The generated heat of the spherical diamond tool propagates and could damage the nerves or coagulate the arteries blood. Little is known about the non-Fourier behavior of heat propagation during bone grinding. Therefore, this study develops an analytical model of the hyperbolic Pennes bioheat transfer equation (HPBTE) to calculate the three-dimensional temperature and necrosis in the grinding region. In vitro experimental investigations were carried out, and the contact zone temperature was measured using an infrared thermography system to validate the proposed thermal model. The results demonstrate that the HPBTE provides more reliable temperature evaluation and thermal damage than Fourier or parabolic heat transfer equation (PHTE). Due to the low thermal diffusivity of the bone, the lower grinding feed rate leads to higher temperature amplitude and a smaller radius of the affected zone in the surface and depth of the bone. Also, the intensity of bone necrosis decreases with the increase of the feed rate, and the shape of the damage zone becomes stretched. This analytical model can assess the potential risk of the surgery before clinical trials. Also, it could be used for comparing the different operating conditions to minimize bone necrosis and improve the control process in neurosurgeries.
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Neurocirugia , Calor , Modelos Biológicos , Procedimientos Neuroquirúrgicos , Base del Cráneo/cirugía , TemperaturaRESUMEN
Background: Due to the growing prevalence of suicide, assessing people's attitudes toward suicide is necessary. Therefore, this study aimed to examine the psychometric properties of the Persian version of the Predicaments Questionnaire (PQ), measuring social attitudes toward suicide. Methods: This psychometrics study evaluated face validity, content validity, temporal stability, internal consistency, and construct validity. First, the questionnaire was translated into Persian by the translate-back-translate method. The Persian version was provided to 10 experts in psychiatry for further revision. Two indicators, CVR and CVI, were calculated to evaluate the content validity. To check the face validity, we prepared a form and gave it to 10 people outside the campus to submit their opinions. Temporal stability was investigated by the test-retest method, reporting Intraclass correlation (ICC). Internal consistency was assessed by reporting Cronbach's alpha and McDonald's Omega coefficients. Construct validity was assessed using the confirmatory factor analysis to determine the number of dimensions of the questionnaire. Results: A total of 151 students were enrolled with a mean age of 25 (SD = 0.32). The Persian PQ was valid in terms of content validity and face validity. Furthermore, it was reliable as Cronbach's alpha, McDonald's Omega, and the ICC were 0.94, 0.943, and 0.998, respectively. In addition, the confirmatory factor analysis yielded one dimension. Finally, after reviewing the experts' comments, the final amendments were made, and only question 29 was removed from the final version. Conclusion: Consequently, the Persian version of the PQ is acceptable in terms of content validity, face validity, temporal stability, and internal consistency.
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Suicidio , Humanos , Adulto , Psicometría , Encuestas y Cuestionarios , Reproducibilidad de los Resultados , Análisis FactorialRESUMEN
Studies of the proteome would benefit greatly from methods to directly sequence and digitally quantify proteins and detect posttranslational modifications with single-molecule sensitivity. Here, we demonstrate single-molecule protein sequencing using a dynamic approach in which single peptides are probed in real time by a mixture of dye-labeled N-terminal amino acid recognizers and simultaneously cleaved by aminopeptidases. We annotate amino acids and identify the peptide sequence by measuring fluorescence intensity, lifetime, and binding kinetics on an integrated semiconductor chip. Our results demonstrate the kinetic principles that allow recognizers to identify multiple amino acids in an information-rich manner that enables discrimination of single amino acid substitutions and posttranslational modifications. With further development, we anticipate that this approach will offer a sensitive, scalable, and accessible platform for single-molecule proteomic studies and applications.
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Proteoma , Proteómica , Aminoácidos/química , Aminopeptidasas , Péptidos/química , Proteómica/métodos , Semiconductores , Análisis de Secuencia de Proteína/métodosRESUMEN
Little is known about the impact behavior of composite fixation plate used in the fracture healing of long bones diaphysis. Hence, this study examined polypropylene composite fixation plates using different glass fibers and measured their biomechanical responses under axial impact loading experimentally and numerically. Short randomly oriented, long unidirectional prepregs and fiber yarn of glass were considered as reinforcements, and fixation plates were fabricated through two different heat-compressing and 3D printing processes. Furthermore, assessing the fixation plate structures impact behavior was carried out using in vitro impact test and finite element analysis (FEA). Impact damping behavior, damage mechanisms, and stress and strain pattern of the composite fixation plate structures were obtained under various bone fractures and impact energies. The impact load-time responses and the failure mechanisms demonstrated that fixation plate structures with more plastic behavior and lower stiffness could act as an initial shock absorber and dampen the transmission of axial impact load by distributing the impact energy over time. Therefore, considering the ability of stress shielding and adequate interfragmentary movement which amplifies bone ossification, the proposed Glass Fiber/PP (GF/PP) composite fixation plates could serve as a proper alternative in orthopedics.
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Placas Óseas , Polipropilenos , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Fijación de Fractura , Fijación Interna de Fracturas , Vidrio , Ensayo de MaterialesRESUMEN
Metallic bone fixations, due to their high rigidity, can cause long-term complications. To alleviate metallic biomaterials' drawbacks, in this research new Glass Fiber/Polypropylene (GF/PP) composite internal fixations were developed, and an investigation of their mechanical behavior was performed through in vitro biomechanical experiments. Short randomly oriented, long unidirectional prepreg, and long unidirectional fiber yarn were considered as reinforcements, and the effects on their mechanical properties of different manufacturing processes, that is, 3D printing and heat-compressing, were investigated. The constructed fixation plates were tested in the transversely fractured diaphysis of bovine tibia under axial compression loading. The overall stiffness and the Von Mises strain field of the fixation plates were obtained within stable and unstable fracture conditions. The samples were loaded until failure to determine their failure loads, strains, and mechanisms. Based on the results, the GF/PP composite fixation plates can provide adequate interfragmentary movement to amplify bone ossification, so they can provide proper support for bone healing. Moreover, their potential for stress shielding reduction and their load-bearing capacity suggest their merits in replacing traditional metallic plates.
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Placas Óseas , Calor , Animales , Fenómenos Biomecánicos , Bovinos , Fijación Interna de Fracturas , Impresión TridimensionalRESUMEN
The most serious complication in today's treatment of congenital haemophilia A is the development of neutralising antibodies (inhibitors) against factor VIII (FVIII). Although FVIII inhibitors can be eliminated by immune tolerance induction (ITI) based on repeated administration of high doses of FVIII, 20-30% of patients fail to become tolerant. Persistence of FVIII inhibitors is associated with increased morbidity and mortality. Data from recent studies provide evidence for a potential association between ITI outcome and epitope specificity of FVIII inhibitors. Nevertheless the determination of epitopes and their clinical relevance has not yet been established. In this study a general strategy for the identification of anti-FVIII antibody epitopes in haemophilia A patient plasma was to be demonstrated. Phage-displayed peptide libraries were screened against anti-FVIII antibodies to isolate specific peptides. Peptide specificity was confirmed by FVIII-sensitive ELISA binding. Peptide residues essential for antibody binding were identified by mutational analysis and epitopes were predicted via FVIII homology search. The proposed mapping strategy was validated for the monoclonal murine antibody (mAb) 2-76. Binding studies with FVIII variants confirmed the location of the predicted epitope at the level of individual amino acids. In addition, anti-FVIII antibody-specific peptide ligands were selected for 10 haemophilia A patients with FVIII inhibitors. Detailed epitope mapping for three of them showed binding sites on the A2, A3 and C2 domains. Precise epitope mapping of anti-FVIII antibodies using antibody-specific peptide ligands can be a useful approach to identify antigenic sites on FVIII.