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This paper presents an approach to enhancing sensitivity in optical sensors by integrating self-image theory and graphene oxide coating. The sensor is specifically engineered to quantitatively assess glucose concentrations in aqueous solutions that simulate the spectrum of glucose levels typically encountered in human saliva. Prior to sensor fabrication, the theoretical self-image points were rigorously validated using Multiphysics COMSOL 6.0 software. Subsequently, the sensor was fabricated to a length corresponding to the second self-image point (29.12 mm) and coated with an 80 µm/mL graphene oxide film using the Layer-by-Layer technique. The sensor characterization in refractive index demonstrated a wavelength sensitivity of 200 ± 6 nm/RIU. Comparative evaluations of uncoated and graphene oxide-coated sensors applied to measure glucose in solutions ranging from 25 to 200 mg/dL showed an eightfold sensitivity improvement with one bilayer of Polyethyleneimine/graphene. The final graphene oxide-based sensor exhibited a sensitivity of 10.403 ± 0.004 pm/(mg/dL) and demonstrated stability with a low standard deviation of 0.46 pm/min and a maximum theoretical resolution of 1.90 mg/dL.
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Platelet-type von Willebrand disease (PT-VWD) is a rare autosomal dominant bleeding disorder characterized by an increased ristocetin-induced platelet aggregation (RIPA) and enhanced affinity of platelet glycoprotein Ibα (GPIbα) to von Willebrand factor (VWF). To date, only seven variants have been described with this gain-of-function effect, most of them located in the C-terminal disulphide loop of the VWF-binding domain of GPIbα. We herein describe a patient with moderate bleeding symptoms, mild thrombocytopenia and increased RIPA. By direct sequencing of GP1BA, a novel leucine-rich repeat heterozygous variant was identified (c.580C>T; predictably p.Leu194Phe), strongly suggestive as being the underlying cause for the PT-VWD phenotype of our patient.
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Doenças de von Willebrand , Fator de von Willebrand , Humanos , Fator de von Willebrand/genética , Mutação com Ganho de Função , Doenças de von Willebrand/diagnóstico , Plaquetas , Hemorragia/genética , Complexo Glicoproteico GPIb-IX de Plaquetas/genéticaRESUMO
Light is a key determinant for plant growth, development, and ultimately yield. Phytochromes, red/far-red photoreceptors, play an important role in plant architecture, stress tolerance, and productivity. In the model plant Arabidopsis, it has been shown that PHYTOCHROME-INTERACTING FACTORS (PIFs; bHLH transcription factors) act as central hubs in the integration of external stimuli to regulate plant development. Recent studies have unveiled the importance of PIFs in crops. They are involved in the modulation of plant architecture and productivity through the regulation of cell division and elongation in response to different environmental cues. These studies show that different PIFs have overlapping but also distinct functions in the regulation of plant growth. Therefore, understanding the molecular mechanisms by which PIFs regulate plant development is crucial to improve crop productivity under both optimal and adverse environmental conditions. In this review, we discuss current knowledge of PIFs acting as integrators of light and other signals in different crops, with particular focus on the role of PIFs in responding to different environmental conditions and how this can be used to improve crop productivity.
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Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas , Fitocromo/genética , Fitocromo/metabolismo , Plantas/metabolismoRESUMO
Thrombocytopenia-absent radius (TAR) syndrome is a rare congenital disorder characterized by the bilateral absence of the radius and thrombocytopenia, and sometimes by other skeletal, gastrointestinal, cardiac, and renal abnormalities. The underlying genetic defect is usually the compound inheritance of a microdeletion in 1q21.1 (null allele) and a low-frequency, non-coding single nucleotide variant (SNV) in the RBM8A gene (hypomorphic allele). We report three new cases from two unrelated families. The two siblings presented the common genotype, namely the compound heterozygosity for a 1q21.1 microdeletion and the hypomorphic SNV c.-21G>A in RBM8A, whereas the third, unrelated patient presented a rare genotype comprised by two RBM8A variants: c.-21G>A (hypomorphic allele) and a novel pathogenic variant, c.343-2A>G (null allele). Of the eight documented RBM8A variants identified in TAR syndrome patients, four have hypomorphic expression and four behave as null alleles. The present report expands the RBM8A null allele spectrum and corroborates the particularities of RBM8A involvement in TAR syndrome pathogenesis.
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Trombocitopenia , Deformidades Congênitas das Extremidades Superiores , Alelos , Síndrome Congênita de Insuficiência da Medula Óssea , Humanos , Proteínas de Ligação a RNA/genética , Rádio (Anatomia) , Trombocitopenia/patologia , Deformidades Congênitas das Extremidades Superiores/genética , Deformidades Congênitas das Extremidades Superiores/patologiaRESUMO
BACKGROUND AND PURPOSE: COVID-19-related acute neurological phenotypes are being increasingly recognised, with neurological complications reported in more than 30% of hospitalised patients. However, multicentric studies providing a population-based perspective are lacking. METHODS: We conducted a retrospective multicentric study at five hospitals in Northern Portugal, representing 45.1% of all hospitalised patients in this region, between 1 March and 30 June 2020. RESULTS: Among 1261 hospitalised COVID-19 patients, 457 (36.2%) presented neurological manifestations, corresponding to a rate of 357 per 1000 in the North Region. Patients with neurologic manifestations were younger (68.0 vs. 71.2 years, p = 0.002), and the most frequent neurological symptoms were headache (13.4%), delirium (10.1%), and impairment of consciousness (9.7%). Acute well-defined central nervous system (CNS) involvement was found in 19.1% of patients, corresponding to a rate of 217 per 1000 hospitalised patients in the whole region. Assuming that all patients with severe neurological events were hospitalised, we extrapolated our results to all COVID-19 patients in the region, estimating that 116 will have a severe neurological event, corresponding to a rate of nine per 1000 (95% CI = 7-11). Overall case fatality in patients presenting neurological manifestations was 19.8%, increasing to 32.6% among those with acute well-defined CNS involvement. CONCLUSIONS: We characterised the population of hospitalised COVID-19 patients in Northern Portugal and found that neurological symptoms are common and associated with a high degree of disability at discharge. CNS involvement with criteria for in-hospital admission was observed in a significant proportion of patients. This knowledge provides the tools for adequate health planning and for improving COVID-19 multidisciplinary patient care.
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COVID-19 , Doenças do Sistema Nervoso , Humanos , Doenças do Sistema Nervoso/epidemiologia , Portugal/epidemiologia , Estudos Retrospectivos , SARS-CoV-2RESUMO
A Fabry-Pérot acoustic sensor based on a graphene oxide membrane was developed with the aim to achieve a faster and simpler fabrication procedure when compared to similar graphene-based acoustic sensors. In addition, the proposed sensor was fabricated using methods that reduce chemical hazards and environmental impacts. The developed sensor, with an optical cavity of around 246 µm, showed a constant reflected signal amplitude of 6.8 ± 0.1 dB for 100 nm wavelength range. The sensor attained a wideband operation range between 20 and 100 kHz, with a maximum signal-to-noise ratio (SNR) of 32.7 dB at 25 kHz. The stability and sensitivity to temperatures up to 90 °C was also studied. Moreover, the proposed sensor offers the possibility to be applied as a wideband microphone or to be applied in more complex systems for structural analysis or imaging.
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Power transformers are central elements of power transmission systems and their deterioration can lead to system failures, causing major disruptions in service. Catastrophic failures can occur, posing major environmental hazards due to fires, explosions, or oil spillage. Early fault detection can be accomplished or estimated using electrical sensors or a chemical analysis of oil or gas samples. Conventional methods are incapable of real-time measurements with a low electrical noise due to time-consuming analyses or susceptibility to electromagnetic interference. Optical fiber sensors, passive elements that are immune to electromagnetic noise, are capable of structural monitoring by being enclosed in power transformers. In this work, optical fiber sensors embedded in 3D printed structures are studied for vibration monitoring. The fiber sensor is encapsulated between two pressboard spacers, simulating the conditions inside the power transformer, and characterized for vibrations with frequencies between 10 and 800 Hz, with a constant acceleration of 10 m/s2. Thermal aging and electrical tests are also accomplished, aiming to study the oil compatibility of the 3D printed structure. The results reported in this work suggest that structural monitoring in power transformers can be achieved using optical fiber sensors, prospecting real-time monitoring.
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RASGRP2 encodes the calcium and diacylglycerol (DAG)-regulated guanine nucleotide exchange factor I (CalDAG-GEFI) identified as a Rap1-activating molecule. Pathogenic variants previously identified in RASGRP2 allowed the characterization of CalDAG-GEFI deficiency as a non-syndromic, autosomal recessive platelet function disease. We report on the clinical manifestations and laboratory features of a Portuguese family with a likely pathogenic variant in RASGRP2 (c.999G>C leading to a p.Lys333Asn change in the CDC25 catalytic domain of CalDAG-GEFI) and discuss the contribution of this variant to the disease manifestations. Based on the study of this family with one homozygous patient and five heterozygous carriers and on a critical analysis of the literature, we challenge previous knowledge that CalDAG-GEFI deficiency only manifests in homozygous patients. Our data suggest that at least for the RASGRP2 variant reported herein, there is a phenotypic expression, albeit milder, in heterozygous carriers.
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Transtornos Plaquetários/sangue , Transtornos Plaquetários/genética , Família , Fatores de Troca do Nucleotídeo Guanina/deficiência , Fatores de Troca do Nucleotídeo Guanina/genética , Heterozigoto , Homozigoto , Adolescente , Adulto , Plaquetas/metabolismo , Domínio Catalítico/genética , Criança , Feminino , Triagem de Portadores Genéticos/métodos , Fatores de Troca do Nucleotídeo Guanina/sangue , Fatores de Troca do Nucleotídeo Guanina/química , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Agregação Plaquetária , Portugal , Adulto JovemRESUMO
Pectin-rich agro-industrial residues are feedstocks with potential for sustainable biorefineries. They are generated in high amounts worldwide from the industrial processing of fruits and vegetables. The challenges posed to the industrial implementation of efficient bioprocesses are however manyfold and thoroughly discussed in this review paper, mainly at the biological level. The most important yeast cell factory platform for advanced biorefineries is currently Saccharomyces cerevisiae, but this yeast species cannot naturally catabolise the main sugars present in pectin-rich agro-industrial residues hydrolysates, in particular D-galacturonic acid and L-arabinose. However, there are non-Saccharomyces species (non-conventional yeasts) considered advantageous alternatives whenever they can express highly interesting metabolic pathways, natively assimilate a wider range of carbon sources or exhibit higher tolerance to relevant bioprocess-related stresses. For this reason, the interest in non-conventional yeasts for biomass-based biorefineries is gaining momentum. This review paper focuses on the valorisation of pectin-rich residues by exploring the potential of yeasts that exhibit vast metabolic versatility for the efficient use of the carbon substrates present in their hydrolysates and high robustness to cope with the multiple stresses encountered. The major challenges and the progresses made related with the isolation, selection, sugar catabolism, metabolic engineering and use of non-conventional yeasts and S. cerevisiae-derived strains for the bioconversion of pectin-rich residue hydrolysates are discussed. The reported examples of value-added products synthesised by different yeasts using pectin-rich residues are reviewed. Key Points ⢠Review of the challenges and progresses made on the bioconversion of pectin-rich residues by yeasts. ⢠Catabolic pathways for the main carbon sources present in pectin-rich residues hydrolysates. ⢠Multiple stresses with potential to affect bioconversion productivity. ⢠Yeast metabolic engineering to improve pectin-rich residues bioconversion. Graphical abstract.
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Agricultura , Resíduos Industriais , Engenharia Metabólica , Pectinas/metabolismo , Leveduras/metabolismo , Biomassa , Carbono/metabolismo , Etanol/metabolismo , Fermentação , Redes e Vias Metabólicas , Pectinas/análise , Açúcares/metabolismo , Leveduras/classificaçãoRESUMO
Conjunctival lymphangiomas are rare hamartomas of lymphatic origin that are usually located in the bulbar conjunctiva. They commonly present either as focal or diffuse bulbar chemosis or as dilatation of lymphatic vessels that resembles an isolated cyst or a group of cysts. There can be bleeding inside the lymphangioma resulting in "chocolate cysts".1 We report the unusual case of a conjunctival lymphangioma on a 36 year-old male that presented as a large horn-like protruding structure. The lesion was surgically removed with simple excision associated with cryotherapy to the lesion's borders, as malignancy could not be ruled out preoperatively. Histopathological examination revealed a lymphangioma composed of an ill-defined proliferation of dilated lymphatic channels in the lamina propria, underlying conjunctival epithelium with squamous metaplasia, acanthosis and hyperkeratosis. One year postoperatively, the patient remains asymptomatic and without recurrence of the lesion.
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INTRODUCTION: Single-haptic iris-claw intraocular lens (IOL) dislocation is not an uncommon complication. A few different surgical techniques are available for its refixation but usually involve a more invasive approach. We aim to demonstrate an original and simple approach for refixation of single haptic retropupillary iris-claw IOL subluxations. METHODS: We present a case of an 80-year-old male with a single haptic retropupillary iris-claw IOL subluxation in a previously vitrectomized eye. We used a new surgical approach to refix this type of subluxation. RESULTS: This new technique uses only two 30-gauge needles (one of them connected to a viscosurgical device) to re-enclavate the subluxated haptic of the retropupillary iris-claw IOL. By minimising surgical manipulation, the patient's postoperative period was uneventful. CONCLUSIONS: We highlight a new, quick, safe, and unusual surgical approach to single-haptic retropupillary iris-claw IOL dislocation in vitrectomized eyes. Because of its characteristics, we named it the "fencing" IOL repositioning technique.
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Migração do Implante de Lente Intraocular , Iris , Lentes Intraoculares , Humanos , Masculino , Idoso de 80 Anos ou mais , Iris/cirurgia , Migração do Implante de Lente Intraocular/cirurgia , Acuidade Visual/fisiologia , Reoperação , Implante de Lente Intraocular/métodos , Vitrectomia/métodos , Desenho de PróteseRESUMO
As lithium-bearing minerals become critical raw materials for the field of energy storage and advanced technologies, the development of tools to accurately identify and differentiate these minerals is becoming essential for efficient resource exploration, mining, and processing. Conventional methods for identifying ore minerals often depend on the subjective observation skills of experts, which can lead to errors, or on expensive and time-consuming techniques such as Inductively Coupled Plasma Mass Spectrometry (ICP-MS) or Optical Emission Spectroscopy (ICP-OES). More recently, Raman Spectroscopy (RS) has emerged as a powerful tool for characterizing and identifying minerals due to its ability to provide detailed molecular information. This technique excels in scenarios where minerals have similar elemental content, such as petalite and spodumene, by offering distinct vibrational information that allows for clear differentiation between such minerals. Considering this case study and its particular relevance to the lithium-mining industry, this manuscript reports the development of an unsupervised methodology for lithium-mineral identification based on Raman Imaging. The deployed machine-learning solution provides accurate and interpretable results using the specific bands expected for each mineral. Furthermore, its robustness is tested with additional blind samples, providing insights into the unique spectral signatures and analytical features that enable reliable mineral identification.
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Optic neuropathies, such as glaucoma, are some of the leading causes of irreversible blindness worldwide. There has been a lot of research for potential therapies that could attenuate and even reduce the impact of the pathological pathways that lead to the loss of retinal ganglion cells (RGCs). In recent years, vitamin B3 (nicotinamide) has gained some interest as a viable option for these neurodegenerative diseases due to its fundamental role in enhancing the mitochondria metabolism of the RGCs. This review focuses on elucidating the impact of vitamin B3 on retinal cells, especially when in a dysfunctional state like what happens in optic neuropathies, especially glaucoma. This review also summarizes the existing and future research on the clinical effects of vitamin B3 in these optic neuropathies, and determines appropriate recommendations regarding its dosing, efficacy, and eventual side effects.
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Glaucoma , Doenças do Nervo Óptico , Humanos , Doenças do Nervo Óptico/tratamento farmacológico , Doenças do Nervo Óptico/etiologia , Glaucoma/metabolismo , Células Ganglionares da Retina/metabolismo , Vitaminas , Suplementos NutricionaisRESUMO
BACKGROUND: Scott syndrome is a mild platelet-type bleeding disorder, first described in 1979, with only 3 unrelated families identified through defective phosphatidylserine (PS) exposure and confirmed by sequencing. The syndrome is distinguished by impaired surface exposure of procoagulant PS on platelets after stimulation. To date, platelet function and thrombin generation in this condition have not been extensively characterized. OBJECTIVES: Genetic and functional studies were undertaken in a consanguineous family with a history of excessive bleeding of unknown cause. METHODS: A targeted gene panel of known bleeding and platelet genes was used to identify possible genetic variants. Platelet phenotyping, flow adhesion, flow cytometry, whole blood and platelet-rich plasma thrombin generation, and specialized extracellular vesicle measurements were performed. RESULTS: We detected a novel homozygous frameshift variant, c.1943del (p.Arg648Hisfs∗23), in ANO6 encoding Anoctamin 6, in a patient with a bleeding history but interestingly with normal ANO6 expression. Phenotyping of the patient's platelets confirmed the absence of PS expression and procoagulant activity but also revealed other defects including reduced platelet δ granules, reduced ristocetin-mediated aggregation and secretion, and reduced P-selectin expression after stimulation. PS was absent on spread platelets, and thrombi formed over collagen at 1500/s. Reduced thrombin generation was observed in platelet-rich plasma and confirmed in whole blood using a new thrombin generation assay. CONCLUSION: We present a comprehensive report of a patient with Scott syndrome with a novel frameshift variant in AN06, which is associated with no platelet PS exposure and markedly reduced thrombin generation in whole blood, explaining the significant bleeding phenotype observed.
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Anoctaminas , Transtornos da Coagulação Sanguínea , Mutação da Fase de Leitura , Hemorragia , Trombina , Adulto , Feminino , Humanos , Masculino , Anoctaminas/genética , Coagulação Sanguínea/genética , Transtornos da Coagulação Sanguínea/genética , Plaquetas/metabolismo , Consanguinidade , Predisposição Genética para Doença , Hemorragia/genética , Hemorragia/sangue , Homozigoto , Linhagem , Fenótipo , Fosfatidilserinas , Proteínas de Transferência de Fosfolipídeos , Agregação Plaquetária , Testes de Função Plaquetária , Trombina/metabolismoRESUMO
Purpose: This study aimedto determine a normative range of intraocular pressure (IOP) values measured with Icare rebound tonometer in premature infants and evaluate IOP variation over time and its correlation with the progression of postconceptional age (PCA). By doing so, we also evaluated advantages of this IOP-measuring method in this population when compared to more traditional methods. Methods: We conducted a single-center prospective study that included premature infants (gestational age ≤32 weeks) who were admitted to the neonatal intensive care unit (NICU) in Hospital Professor Doutor Fernando Fonseca. The study took place between January and December 2021. IOP was measured using Icare tonometer on the occasion of the first retinopathy of prematurity (ROP) screening requested by the NICU and again after a two-week interval if PCA was still ≤37 weeks. IOP measurements were stopped at 37 weeks or if the infant was discharged. The evaluated outcomes were mean IOP values and their correlation with PCA. Results: Thirty-four eyes of 17 preterm infants with a mean gestational age of 29.4 ± 2.3 weeks and a mean birth weight of 1222.9 ± 361.9 gr were evaluated. The mean IOP registered was 16.1 ± 6.4 mmHg, with a median value of 15.3 mmHg. The top 90th percentile was 22.1 mmHg and the bottom 10th percentile was 9.0 mmHg. The average IOP reduction was 4.8 ± 6.7 mmHg (P = 0.0019) within the two-week interval of PCA. Conclusion: The mean IOP in premature infants was 16.1 ± 6.4 mmHg and this value significantly decreased by 4.8 ± 6.7 mmHg every two weeks of PCA.
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Anxiety contributes to postsurgical pain, and midazolam is frequently prescribed preoperatively. Conflicting results have been described concerning the impact of midazolam on pain. This study aims to evaluate the effect of systemic midazolam on pain after open inguinal hernia repair, clarifying its relationship with preoperative anxiety. A prospective observational cohort study was conducted in three Portuguese ambulatory units between September 2018 and March 2020. Variable doses of midazolam were administered. Postsurgical pain was evaluated up to three months after surgery. We enrolled 306 patients and analyzed 281 patients. The mean preoperative anxiety Numeric Rating Scale score was 4 (3) and the mean Surgical Fear Questionnaire score was 22 (16); the mean midazolam dose was 1.7 (1.1) mg with no correlation to preoperative anxiety scores. Pain ≥4 was present in 67% of patients 24 h after surgery and in 54% at seven days; at three months, 27% were classified as having chronic postsurgical pain. Preoperative anxiety correlated to pain severity at all time points. In multivariable regression, higher midazolam doses were associated with less pain during the first week, with no apparent effect on chronic pain. However, subgroup analyses uncovered an effect modification according to preoperative anxiety: the decrease in acute pain occurred in the low-anxiety patients with no effect on the high-anxiety group. Inversely, there was an increase in chronic postsurgical pain in the very anxious patients, without any effect on the low-anxiety group. Midazolam, generally used as an anxiolytic, might impact distinctively on pain depending on anxiety.
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Optical coherence tomography angiography (OCTA) is a recent noninvasive imaging technology that has proved to provide a comprehensive evaluation of retinal vascular abnormalities in adult patients with sickle cell disease (SCD). However, the pediatric population remains less studied. The purpose of this study is to evaluate the correlation between temporal vessel density (VD) in OCTA and temporal macular thinning in optical coherence tomography (OCT) in children and young adults with SCD. We reviewed medical records, OCT and OCTA (Spectralis®) scans from a sample of 32 eyes from 16 patients (7 female + 9 male) under 25 years old. The OCT macular thickness data and OCTA image data were processed using Python 3.9 programming language, and statistical analysis was performed. Pearson Correlation Coefficient between macular thickness and VD for inner and outer temporal areas was 0.47 (p-value = 0.006) and 0.74 (p-value < 0.001), respectively. A t-test was also performed to prove that there is a statistically significant VD difference in patients with higher and lower macular thickness (p < 0.001). These results show that children with outer temporal macular thinning on OCT have lower outer temporal VD on OCTA suggesting that microvascular insults may lead to chronic ischemic changes in the inner retinal layers.
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Opiates recreational consumption has always been a concern in society, public health, and in clinical toxicology analysis. The aim of this study was to develop and fully validate an analytical method, which was simple and rapid for the determination of tramadol, codeine, morphine, 6- acetylcodeine, 6-monoacetylmorphine and fentanyl using gas chromatography coupled to tandem mass spectrometry. The procedure includes the use of microextraction by packed sorbent for sample clean-up. A mixed mode sorbent was used, allowing the minimal use of solvents. The method was validated in urine samples, with the ability to detect and quantify all analytes with satisfactory linearity (in the range of 1 - 1000 ng/mL for all analytes, except for fentanyl (10-1000 ng/mL)). Extraction efficiency varied from 17 to 107%, which did not impair sensitivity, taking into account the low LLOQs obtained (1 ng/ mL for all analytes; and 10 ng/mL for fentanyl). The developed procedure proved to be fast, selective, and accurate for use in routine analysis, with a low volume of sample (250 µL).
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Alcaloides Opiáceos , Analgésicos Opioides , Fentanila , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodosRESUMO
INTRODUCTION: Extramedullary plasmacytomas are present in 13% of multiple myeloma (MM) patients. Less than 5% of MM cases are non-secretory. The orbital location is uncommon and a minority of orbital tumours are plasmacytomas. DESCRIPTION: The patient was a 71-year-old man, with right proptosis, retro-ocular pain and epistaxis with visual acuity 2/10, limitation of upper eye movement and scattered ecchymosis. Blood tests revealed severe anaemia, coagulopathy, increased serum creatinine, LDH and C-RP without improvement after antimicrobial treatment. Peripheral immunophenotyping showed 9.4% of plasma cells with intracytoplasmic clonal κ chains. IgG and λ chains were decreased with normal plasma and urine immunofixation. Orbital CT: retro-orbital superomedial tumour with bone destruction. Histology of the tumour and bone biopsy was consistent with plasmacytoma. The patient was deceased in 2 weeks. DISCUSSION: MM accounts for 10% of haematopoietic tumours; 7% of cases present with plasmacytomas at diagnosis. Orbital locations are rarely reported (frequently in the temporal region). Proptosis, ptosis and reduced visual acuity are common symptoms. However, orbital pain is less frequent. Most cases of MM demonstrate hypergammaglobulinaemia. Only 5% of MM cases are non-secretory.The uncommon location, topography, symptom peculiarities and absence of monoclonality led to the diagnostic challenge of this fatal case of MM. LEARNING POINTS: Multiple myeloma (MM) represents 10% of malignant haematologic disease, 13% of which presents plasmacytomas (mostly in the axial skeleton).Orbital plasmacytoma is an uncommon presentation of MM and only 1% of orbital tumours are plasmacytomas. Proptosis is the most common symptom.Although the majority of MM cases demonstrate hypergammaglobulinaemia, non-secretory MM is described as constituting less than 5% of cases.
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BACKGROUND: Rare pathogenic variants in either the ITGA2B or ITGB3 genes have been linked to autosomal dominant macrothrombocytopenia associated with abnormal platelet production and function, deserving the designation of Glanzmann Thrombasthenia-Like Syndrome (GTLS) or ITGA2B/ITGB3-related thrombocytopenia. OBJECTIVES: To describe a series of patients with familial macrothrombocytopenia and decreased expression of αIIbß3 integrin due to defects in the ITGA2B or ITGB3 genes. METHODS: We reviewed the clinical and laboratory records of 10 Portuguese families with GTLS (33 patients and 11 unaffected relatives), including the functional and genetic defects. RESULTS: Patients had absent to moderate bleeding, macrothrombocytopenia, low αIIbß3 expression, impaired platelet aggregation/ATP release to physiological agonists and low expression of activation-induced binding sites on αIIbß3 (PAC-1) and receptor-induced binding sites on its ligand (bound fibrinogen), upon stimulation with TRAP-6 and ADP. Evidence for constitutive αIIbß3 activation, occurred in 2 out of 9 patients from 8 families studied, but also in 2 out of 12 healthy controls. We identified 7 missense variants: 3 in ITGA2B (5 families), and 4 in ITGB3 (5 families). Three variants (αIIb: p.Arg1026Trp and p.Arg1026Gln and ß3: p.Asp749His) were previously reported. The remaining (αIIb: p.Gly1007Val and ß3: p.Thr746Pro, p.His748Pro and p.Arg760Cys) are new, expanding the αIIbß3 defects associated with GTLS. The integration of the clinical and laboratory data allowed the identification of two GTLS subgroups, with distinct disease severity. CONCLUSIONS: Previously reported ITGA2B and ITGB3 variants related to thrombocytopenia were clustered in a confined region of the membrane-proximal cytoplasmic domains, the inner membrane clasp. For the first time, variants are reported at the outer membrane clasp, at the transmembrane domain of αIIb, and at the membrane distal cytoplasmic domains of ß3. This is the largest single-center series of inherited macrothrombocytopenia associated with αIIbß3 variants published to date.