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1.
Med Mycol Case Rep ; 44: 100642, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38516610

RESUMO

Male cat, 2 years old, with a refractory infection by Sporothrix brasiliensis, presents a single nodular lesion in the left auricular pavilion. To confirm the diagnosis, cytology, fungal culture, antifungal susceptibility test, molecular analysis, and, to aid in the differential diagnosis, bacterial culture, antibiogram, and histopathology of the lesion were performed. In the absence of therapeutic success with conventional antifungals, photodynamic therapy (PDT) was introduced, demonstrating a satisfactory response in the sixth treatment session.

2.
Braz J Microbiol ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466550

RESUMO

The drugs available to treat sporotrichosis, an important yet neglected fungal infection, are limited. Some Sporothrix spp. strains present reduced susceptibility to these antifungals. Furthermore, some patients may not be indicated to use these drugs, while others may not respond to the therapy. The anthelmintic drug niclosamide is fungicidal against the Sporothrix brasiliensis type strain. This study aimed to evaluate whether niclosamide also has antifungal activity against Sporothrix globosa, Sporothrix schenckii and other S. brasiliensis strains with distinct genotypes and antifungal susceptibility status. Minimal inhibitory and fungicidal concentrations (MIC and MFC, respectively) were determined using the microdilution method according to the CLSI protocol. The checkerboard method was employed to evaluate niclosamide synergism with drugs used in sporotrichosis treatment. Metabolic activity of the strains under niclosamide treatment was evaluated using the resazurin dye. Niclosamide was active against all S. brasiliensis strains (n = 17), but it was ineffective (MIC > 20 µM) for some strains (n = 4) of other pathogenic Sporothrix species. Niclosamide MIC values for Sporothrix spp. were similar for mycelial and yeast-like forms of the strains (P = 0.6604). Niclosamide was fungicidal (MFC/MIC ratio ≤ 2) for most strains studied (89%). Niclosamide activity against S. brasiliensis is independent of the fungal genotype or non-wild-type phenotypes for amphotericin B, itraconazole, or terbinafine. These antifungal drugs presented indifferent interactions with niclosamide. Niclosamide has demonstrated potential for repurposing as a treatment for sporotrichosis, particularly in S. brasiliensis cases, instigating in vivo studies to validate the in vitro findings.

3.
J Palliat Care ; : 8258597241231005, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374645

RESUMO

Objective: Some patients with cancer admitted to palliative care have relatively long survivals of 1 year or more. The objective of this study was to find out factors associated with prolonged survival. Methods: Retrospective case-control study comparing the available data of patients with cancer who survived more than 1 year after admission in a palliative care service with patients with cancer who survived 6 months or less. The intended proportion was 4 controls for each case. Patients were identified through electronic records from 2012 until 2018. Results: And 1721 patients were identified. Of those patients, 111 (6.4%) survived for at least 1 year, and 363 (21.1%) were included as controls according to the established criteria. The intended proportion could not be reached; the proportion was only 3.3:1. The median survival of cases was 581 days (range: 371-2763), and the median survival of controls was 57 days (range: 1-182). In the multivariable analysis, patients with a hemoglobin ≥ 10.6 g/dL and a creatinine level >95 µmol/L had a higher probability of living more than 1 year. In contrast, patients with abnormal cognition, pain, anorexia, liver metastases, an Eastern Cooperative Oncology Group performance status >1, and a neutrophil/lymphocyte ratio ≥ 3.43 had a low probability of living more than 1 year. Conclusion: Several factors were statistically associated positively or negatively with prolonged survival. However, the data of this study should be confirmed in other studies.

4.
Cureus ; 16(2): e54930, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38410626

RESUMO

Acute alithiatic cholecystitis is an inflammation of the gallbladder without evidence of gallstones, often due to infection. It can occur at any age, and it is predominant in males. Listeriosis is a rare bacterial infection caused by Listeria monocytogenes (LM) through the ingestion of contaminated food such as dairy, legumes, and raw meats. Clinical presentations of listeriosis include bacteremia, meningitis, and gastroenteritis. Acute cholecystitis caused by listeria is even more uncommon, with only 23 cases reported in the literature. We present a case of a 65-year-old male, admitted to the Emergency Department with fever and altered state of consciousness which revealed bacteremia due to cholecystitis to LM. The patient was submitted to laparoscopic cholecystectomy and appropriate antibiotic coverage and was discharged seven days later. Early recognition and treatment of this disease are crucial for reducing morbidity and mortality.

5.
Cureus ; 16(1): e51691, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38187024

RESUMO

Periorbital emphysema is rare and associated with facial trauma. Its main distinguishing feature is crepitation on palpation of the edema. It resolves spontaneously in a few days, but there are cases of orbital compartment syndrome that can lead to loss of vision. Here we present the case of a 55-year-old male who came to the emergency department for bilateral periorbital edema associated with non-steroidal anti-inflammatory drug (NSAID) usage, for pain following a fall from a ladder. He was treated with antihistamines and corticosteroids, for presumed allergic reaction, but without response, and subsequently developed acute onset dyspnea. Chest x-ray revealed a left pneumothorax in the context of chest trauma. Chest CT scan after drain placement shows extensive subcutaneous emphysema. In the differential diagnosis of periorbital edema, in addition to allergic, inflammatory, and systemic causes, the traumatic ones should not be excluded.

6.
Hum Reprod ; 39(2): 293-302, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38088127

RESUMO

Many recent societal trends have led to the need for fertility education, including the age at which individuals become parents, the development of new reproductive technologies, and family diversity. Fertility awareness has emerged as a concept very recently and is increasingly gaining recognition. However, fertility education is often neglected as there is no consensus on the appropriate content, target populations, or on who should provide it. This article attempts to provide an overview of the use of interventions to improve fertility education. We emphasize the importance of delivering evidence-based information on fertility and reproductive health through various methods while providing guidelines for their standardization and systematization. Recommendations are provided to aid the development and implementation of fertility education tools, including: the establishment of a comprehensive understanding of the target populations; the incorporation of theories of behavioural change; the inclusion of the users' perspectives and the use of participatory research; and the use of specific guidelines for increasing engagement. By following these recommendations, it is expected that fertility education resources can contribute to improving fertility literacy, empowering individuals and couples to make informed reproductive decisions, and ultimately reducing the incidence of infertility and need for fertility treatment.


Assuntos
Infertilidade , Alfabetização , Humanos , Fertilidade , Aconselhamento , Reprodução , Infertilidade/terapia
7.
JBRA Assist Reprod ; 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38091259

RESUMO

The new coronavirus pandemic resulted in millions of deaths in Brazil and around the world, and presented substantial challenges to society. The shortand long-term clinical manifestations tied to COVID-19 are still poorly understood, and may involve several organs and systems, including the male genital tract, which may lead to impaired fertility. The present study aimed to analyze, through an integrative literature review of articles available in databases, the effects of COVID-19 on parameters related to human semen quality. The analyzed studies reported significant decreases in sperm motility and morphology related to COVID-19. Reductions in concentration and volume were also observed. Inflammatory response is one of the leading mechanisms that may potentially explain the observed changes, although others may also be involved. More studies are needed to better understand the effects, modes of action, as well as other aspects involved in this complex phenomenon.

8.
Biomolecules ; 13(10)2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37892144

RESUMO

The global trend of rising (male) infertility is concerning, and the unidentifiable causes in half of the cases, the so-called unknown origin male infertility (UOMI), demands a better understanding and assessment of both external/internal factors and mechanisms potentially involved. In this work, it was our aim to obtain new insight on UOMI, specifically on idiopathic (ID) and Unexplained male infertility (UMI), relying on a detailed evaluation of the male gamete, including functional, metabolic and proteomic aspects. For this purpose, 1114 semen samples, from males in couples seeking infertility treatment, were collected at the Reproductive Medicine Unit from the Centro Hospitalar e Universitário de Coimbra (CHUC), from July 2018-July 2022. Based on the couples' clinical data, seminal/hormonal analysis, and strict eligibility criteria, samples were categorized in 3 groups, control (CTRL), ID and UMI. Lifestyle factors and anxiety/depression symptoms were assessed via survey. Sperm samples were evaluated functionally, mitochondrially and using proteomics. The results of Assisted Reproduction Techniques were assessed whenever available. According to our results, ID patients presented the worst sperm functional profile, while UMI patients were similar to controls. The proteomic analysis revealed 145 differentially expressed proteins, 8 of which were specifically altered in ID and UMI samples. Acrosin (ACRO) and sperm acrosome membrane-associated protein 4 (SACA4) were downregulated in ID patients while laminin subunit beta-2 (LAMB2), mannose 6-phosphate isomerase (MPI), ATP-dependent 6-phosphofructokinase liver type (PFKAL), STAR domain-containing protein 10 (STA10), serotransferrin (TRFE) and exportin-2 (XPO2) were downregulated in UMI patients. Using random forest analysis, SACA4 and LAMB2 were identified as the sperm proteins with a higher chance of distinguishing ID and UMI patients, and their function and expression variation were in accordance with the functional results. No alterations were observed in terms of lifestyle and psychological factors among the 3 groups. These findings obtained in an experimental setting based on 3 well-defined groups of subjects, might help to validate new biomarkers for unknown origin male infertility (ID and UMI) that, in the future, can be used to improve diagnostics and treatments.


Assuntos
Infertilidade Masculina , Sêmen , Humanos , Masculino , Sêmen/metabolismo , Análise do Sêmen , Proteômica/métodos , Espermatozoides/metabolismo
9.
Pharmaceuticals (Basel) ; 16(10)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37895871

RESUMO

Ageratina pichinchensis (Kunth) R.M. King & H. Rob. belongs to the Asteraceae family and is a plant native to Mexico to which several biological properties are attributed. In this study, the cytotoxic effect of four extracts from the wild plants and two extracts from A. pichinchensis callus culture were evaluated against carcinogenic cell lines including prostate carcinoma, cervical cancer, hepatocellular carcinoma, hepatoma human, lung cancer, and cellular keratinocytes. The extracts were obtained with ethyl acetate and methanol using both leaves and stems or the callus. Only the ethyl acetate extract of the callus culture influenced the cervical cancer cell line (HeLa) with an IC50 of 94.79 ± 2.0 µg/mL. From the ethyl acetate callus extract, 2,3-dihydrobenzofuran was isolated and purified and also evaluated against cancer cells. The cytotoxic evaluation of this compound showed a significant effect against the HeLa cell line with an IC50 of 23.86 ± 2.5 µg/mL. Our results contribute to the development of biotechnological alternatives and extraction processes to produce compounds with possible potential against certain types of human cancer.

11.
Med Mycol ; 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170071

RESUMO

Nannizzia gypsea is a geophylic agent of human and animal dermatophytosis. This study compares the metabolic and morphostructural plasticity of N. gypsea strains isolated from moss, sand, and a dog. The in vitro metabolic plasticity included the detection of extracellular enzymes, thermotolerance, resistance to oxidative stress, and assessment of fungal growth. Structural plasticity studies included cell surface hydrophobicity, electronegativity, and size of macroconidia. Virulence was assessed on Tenebrio mollitor model. The strains showed low thermotolerance, susceptibility to oxidative stress, and were producers of keratinase, lipase and catalase. N. gypsea strains were unable to produce hemolysin, esterase, and phospholipase although they were able to grow with different carbon sources. The electronegative properties of the surface did not vary between the strains under study. The knowledge about N. gypsea metabolic and morphostructural plasticity could be crucial for the development of therapeutic strategies and control of dermatophytosis.


Nannizzia gypsea causes dermatophytosis due to its metabolic and morphostructural plasticity. Investigations on the fungus-host interaction are essential for the development of therapeutic intervention strategies and control of this important zoonoses in the world Public Health scenario.

12.
Biomolecules ; 13(5)2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37238616

RESUMO

Acmella radicans (Asteraceae) is a plant native to America. Despite it having medicinal attributes, studies on its phytochemical properties are scarce, and biotechnological studies do not exist for this species. In this study, we established an adventitious root culture from A. radicans internodal segments in shake flasks with indole-3-butyric acid (IBA), and then elicited it with jasmonic acid (JA) and salicylic acid (SA). The total phenolic content and antioxidant activity were evaluated, and a comparison was made using in vitro plantlets and wild plants. Internodal segments with 0.1 mg/L IBA showed 100% root induction and exhibited better growth after transfer to shake flasks with MS liquid culture medium. JA had a significant effect on biomass increase compared to unelicited roots, mainly with 50 µM JA (28%), while SA did not show significant results. Root elicited with 100 µM (SA and JA) showed a 0.34- and 3.9-fold increase, respectively, in total phenolic content (TPC) compared to the control. The antioxidant activity was also significant, and a lower half-maximal inhibitory concentration (IC50) was observed as the AJ concentration increased. Roots elicited with AJ (100 µM) exhibited high antioxidant activity with DPPH (IC50 = 9.4 µg/mL) and ABTS (IC50 = 3.3 µg/mL) assays; these values were close to those for vitamin C (IC50 = 2.0 µg/mL). The TPC and antioxidant activity of in vitro plants and root cultured in shake flasks showed the lowest values in most cases; even the root cultures without elicitation were better than those of a wild plant. In this study, we demonstrated that A. radicans root culture is capable of producing secondary metabolites, while its production and antioxidant activity can be enhanced using jasmonic acid.


Assuntos
Antioxidantes , Asteraceae , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Biomassa , Ácido Salicílico/farmacologia
13.
Cureus ; 15(3): e35690, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37012960

RESUMO

INTRODUCTION: Polycystic ovary syndrome (PCOS) is a common endocrine disorder often leading to anovulatory infertility. PCOS pathophysiology is still unclear and several potential genetic susceptibility factors have been proposed. The effect of polymorphisms in two genesrelated to follicular recruitment and development, the follicle-stimulating hormone receptor (FSHR) and the estrogen receptor 1 (ESR1), have been studied in different populations with contradictory results. AIMS: To evaluate the influence of FSHR rs6166 (c.2039A>G) and of ESR1 rs2234693 (Pvull c.453-397 T > C) polymorphisms on PCOS risk, phenotype, and response to controlled ovarian stimulation (COS). MATERIALS AND METHODS: Genotyping of the FSHR rs6166 and the ESR1 rs2234693 polymorphisms was performed in PCOS women and a control group undergoing in vitro fertilization (IVF). Demographic, clinical, and biochemical data, genotype frequency, and IVF outcomes were compared between groups. RESULTS: We evaluated 88 PCOS women and 80 controls. There was no significant difference in the genotype distribution of FSHR rs6166 polymorphism between PCOS women and controls (AA 31.8%/AS 48.9%/SS 19.3% in PCOS women vs AA 37.5%/AS 40.0%/SS 22.5% in controls; p = 0.522). The same was true for the ESR1 rs2234693 (CC 24.1%/CT 46.0%/TT 29.9% in PCOS women vs CC 18.8%/CT 48.8%/TT 32.5% in controls; p = 0.697). In PCOS women, we found higher follicle-stimulating hormone (FSH) levels on the third day of the menstrual cycle associated with the SS variant of the FSHR polymorphism (9.2 vs 6.2 ± 1.6 and 5.6 ± 1.6 mUI/mL; p = 0.011). We did not find other associations between the baseline hormonal parameters, antral follicle count, and response measures to COS with FSHR or ESR1 genotypes. We found, however, a need for higher cumulative doses of FSH for COS in patients with the SS variant of the FSHR rs6166 polymorphism (1860.5 ± 627.8 IU for SSvs 1498.1 ± 359.3 for AA and 1425.4 ± 474.8 for SA; p = 0.046 and p = 0.046). CONCLUSION: Our data suggest that in the population, FSHR rs6166and ESR1 rs2234693 polymorphisms do not influence the risk of developing PCOS nor do they influence the patient's phenotype and IVF success. However, the SS variant of the FSHR rs6166 polymorphism may be associated with FSH resistance requiring higher FSH doses for COS.

14.
Cureus ; 15(3): e36281, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36937126

RESUMO

Acute generalized exanthematous pustulosis (AGEP) is a rare and severe skin disorder induced in more than 90% of cases by an adverse drug reaction. This condition is defined by an acute growth of numerous, pin-head-sized, non-follicular pustules on a background of edematous erythema that starts on the face or in the armpits and groin. It is accompanied by fever and increased inflammatory markers. We present a case of a 39-year-old male, admitted to the internal medicine department due to Streptococcus pneumoniae meningitis treated with ceftriaxone, who developed erythema covered with small sterile pustules in the face, neck, and axilla four days after antibiotic treatment. The clinical and pathological correlations confirmed the diagnosis, and the dermatosis resolved after discontinuing the drug and systemic corticosteroid treatment. Early recognition of this drug-induced dermatosis is crucial for adequate treatment.

15.
Molecules ; 28(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36677637

RESUMO

Ageratina pichinchensis (Kunth) R.King & Ho.Rob. is a plant used in traditional Mexican medicine, and some biotechnological studies have shown that its calluses and cell suspension cultures can produce important anti-inflammatory compounds. In this study, we established a cell culture of A. pichinchensis in a 2 L airlift bioreactor and evaluated the production of the anti-inflammatory compounds 2,3-dihydrobenzofuran (1) and 3-epilupeol (2). The maximum biomass production (11.90 ± 2.48 g/L) was reached at 11 days of culture and cell viability was between 80% and 90%. Among kinetic parameters, the specific growth rate (µ) was 0.2216 days-1 and doubling time (td) was 3.13 days. Gas chromatography coupled with mass spectrometry (GC-MS) analysis of extracts showed the maximum production of compound 1 (903.02 ± 41.06 µg/g extract) and compound 2 (561.63 ± 10.63 µg/g extract) at 7 and 14 days, respectively. This study stands out for the significant production of 2,3-dihydrobenzofuran and 3-epilupeol and by the significant reduction in production time compared to callus and cell suspension cultures, previously reported. To date, these compounds have not been found in the wild plant, i.e., its production has only been reported in cell cultures of A. pichinchensis. Therefore, plant cell cultured in an airlift reactor can be an alternative for the improved production of these anti-inflammatory compounds.


Assuntos
Ageratina , Extratos Vegetais , Extratos Vegetais/química , Ageratina/química , Fotoperíodo , Escuridão , Reatores Biológicos , Técnicas de Cultura de Células , Anti-Inflamatórios
16.
Front Psychol ; 14: 1198074, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38449468

RESUMO

Introduction: The delivery of social and emotional learning (SEL) programs that are developmentally school-based and evidence-based has the potential to benefit many children, and as such, greater efforts are needed to disseminate these programs more widely within the community. The Incredible Years® Teacher Classroom Management (IY-TCM) has shown promising results when applied by teachers in preschool centers and primary schools, as seen in several randomized control trials conducted worldwide, including in Portugal. Methods: The current study presents a model of the implementation of the program within the framework of a nationwide initiative undertaken in Portugal: the Academias Gulbenkian do Conhecimento. Additionally, results of the program's impact on children were explored using ANOVA, which compared pre- to post- treatment outcomes. To assess which factors affected the efficacy of the intervention, moderation analyses were conducted using the MEMORE macro. Ninety teachers and 535 children (2 to 10 years old) were assessed. Results: Results revealed that children showed significant increases in social and emotional skills (e.g., social adjustment, empathy) and significant reductions in problem behavior when assessed by their teachers, and in social-cognitive problem solving strategies as evaluated by a set of problem-solving tasks. Moderation analyses showed that, in general, interaction effects were not found, meaning that the intervention was effective for almost all conditions. Nevertheless, significant moderation effects were found for factors pertaining to the child and the mother with respect to pro-social and emotional skills (children who benefited most from the intervention exhibited more behavioral difficulties at the baseline according to the teachers' perceptions and had mothers without a university degree; children attending primary school took less benefit from the intervention than those attending pre-school). Discussion: The findings contribute both to the reinforcement of the effectiveness of the IY-TCM program as a universal intervention in "real world" schools and to the development of some guidelines for the promotion of effective scaling up and sustainability of program effects.

17.
Int J Mol Sci ; 23(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36362125

RESUMO

Non-canonical splice site variants are increasingly recognized as a relevant cause of the USH2A-associated diseases, non-syndromic autosomal recessive retinitis pigmentosa and Usher syndrome type 2. Many non-canonical splice site variants have been reported in public databases, but an effect on pre-mRNA splicing has only been functionally verified for a subset of these variants. In this study, we aimed to extend the knowledge regarding splicing events by assessing a selected set of USH2A non-canonical splice site variants and to study their potential pathogenicity. Eleven non-canonical splice site variants were selected based on four splice prediction tools. Ten different USH2A constructs were generated and minigene splice assays were performed in HEK293T cells. An effect on pre-mRNA splicing was observed for all 11 variants. Various events, such as exon skipping, dual exon skipping and partial exon skipping were observed and eight of the tested variants had a full effect on splicing as no conventionally spliced mRNA was detected. We demonstrated that non-canonical splice site variants in USH2A are an important contributor to the genetic etiology of the associated disorders. This type of variant generally should not be neglected in genetic screening, both in USH2A-associated disease as well as other hereditary disorders. In addition, cases with these specific variants may now receive a conclusive genetic diagnosis.


Assuntos
Síndromes de Usher , Humanos , Síndromes de Usher/genética , Células HEK293 , Precursores de RNA , Proteínas da Matriz Extracelular/genética , Mutação , Sítios de Splice de RNA/genética
18.
Mycopathologia ; 187(4): 375-384, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35778635

RESUMO

Feline sporotrichosis has emerged as an important public health issue in some countries, especially Brazil. Currently, zoonotic transmission of Sporothrix brasiliensis by domestic cats is the major sporotrichosis spread form throughout this country. Sporotrichosis in Brazil is a good model for the One Health concept application, which connects the environment, human and animal health. Under this thinking, the aim of this study was to investigate the seroprevalence of sporotrichosis in cats from Rolim de Moura, Rondônia, Brazil, using antibody detection by an ELISA test previously validated for human diagnosis. For the standardization of this test, 30 serum samples from cats with proven sporotrichosis and 11 sera from healthy cats were used. The assay showed 87% sensitivity and 100% specificity for the diagnosis of feline sporotrichosis. After the standardization, 202 serum samples from distinct cats from Rolim de Moura were evaluated. The test was positive in 63 (31.19%) cats from the studied area. A multivariate analysis revealed that living far from forest or agricultural areas as well as pure breed animals had higher odds ratios (3.157 and 2.281, respectively) for the presence of detectable levels of anti-Sporothrix antibodies. These results show the applicability of this assay in the detection of anti-Sporothrix antibodies in feline serum samples and point to a putative new occurrence area of urban sporotrichosis dispersing to the North region of Brazil.


Assuntos
Doenças do Gato , Esporotricose , Animais , Brasil/epidemiologia , Doenças do Gato/diagnóstico , Doenças do Gato/epidemiologia , Gatos , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Estudos Soroepidemiológicos , Esporotricose/diagnóstico , Esporotricose/epidemiologia , Esporotricose/veterinária
19.
NPJ Genom Med ; 7(1): 37, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672333

RESUMO

The USH2A variant c.2276 G > T (p.(Cys759Phe)) has been described by many authors as a frequent cause of autosomal recessive retinitis pigmentosa (arRP). However, this is in contrast with the description of two asymptomatic individuals homozygous for this variant. We therefore assessed pathogenicity of the USH2A c.2276 G > T variant using extensive genetic and functional analyses. Whole genome sequencing and optical genome mapping were performed for three arRP cases homozygous for USH2A c.2276 G > T to exclude alternative genetic causes. A minigene splice assay was designed to investigate the effect of c.2276 G > T on pre-mRNA splicing, in presence or absence of the nearby c.2256 T > C variant. Moreover, an ush2ap.(Cys771Phe) zebrafish knock-in model mimicking human p.(Cys759Phe) was generated and characterized using functional and immunohistochemical analyses. Besides the homozygous c.2276 G > T USH2A variant, no alternative genetic causes were identified. Evaluation of the ush2ap.(Cys771Phe) zebrafish model revealed strongly reduced levels of usherin expression at the photoreceptor periciliary membrane, increased levels of rhodopsin localization in the photoreceptor cell body and decreased electroretinogram (ERG) b-wave amplitudes compared to wildtype controls. In conclusion, we confirmed pathogenicity of USH2A c.2276 G > T (p.(Cys759Phe)). Consequently, cases homozygous for c.2276 G > T can now receive a definite genetic diagnosis and can be considered eligible for receiving future QR-421a-mediated exon 13 skipping therapy.

20.
Sci Rep ; 12(1): 6135, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35414093

RESUMO

Optical homodyne detection is widely adopted in continuous-variable quantum key distribution for high-rate field measurement quadratures. Besides that, those detection schemes have been being implemented for single-photon statistics characterization in the field of quantum tomography. In this work, we propose a discrete-variable quantum key distribution (DV-QKD) implementation that combines the use of phase modulators for high-speed state of polarization (SOP) generation, with a conjugate homodyne detection scheme which enables the deployment of high speed QKD systems. The channel discretization relies on the application of a detection threshold that allows to map the measured voltages as a click or no-click. Our scheme relies also on the use of a time-multiplexed pilot tone-quantum signal architecture which enables the use of a Bob locally generated local oscillator and opens the door to an effective polarization drift compensation scheme. Besides that, our results shows that for higher detection threshold values we obtain a very low quantum bit error rate (QBER) on the sifted key. Nevertheless, due to huge number of discarded qubits the obtained secure key length abruptly decreases. From our results, we observe that optimizing the detection threshold and considering a system operating at 500 MHz symbol generation clock, a secure key rate of approximately 46.9 Mbps, with a sifted QBER of  [Formula: see text] over 40 km of optical fiber. This considering the error correction and privacy amplification steps necessary to obtain a final secure key.

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