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All-inorganic perovskite quantum dots with the usual cubic shape have emerged as a successful and low-cost alternative to electronically functional nanomaterials motivating various fields of applications, including high-efficiency photovoltaics. Here, we present an efficient and almost analytic approach for optical absorption coefficient calculation on self-assembled perovskite quantum dot films with type-II band alignment. The approach takes advantage of the special point technique for integration over the two-dimensional Brillouin zone, which minimizes the computational cost. The set of special wave-vector points is generated using the Monkhorst and Pack method. The optical absorption spectrum for phenyl-C60-butyric acid methyl ester (PCBM)/CsPbI3quantum dot films is computed, in good agreement with the experiment assuming a homogeneous linewidth of 50 meV and considering a ten special-point set. We show that light absorption in these systems is a cooperative optoelectronic property resulting from the quantum-mechanical coupling between perovskite nanocubes, leading to extended system states. The generality of this approach makes it suitable for calculating the optical absorption coefficient in a broad class of perovskite quantum dot systems.

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INTRODUCTION: This study standardized a semi-quantitative dot blotting assay (DB) and a quantitative real-time polymerase chain reaction (qPCR) to detect specific antibodies for Paracoccidioides brasiliensis and its DNA in PCM patients. METHODOLOGY: We evaluated 42 confirmed PCM patients upon admission using a serological double agar gel immunodiffusion test (DID), DB, and molecular tests (qPCR in total blood). The control groups included 42 healthy individuals and 37 patients with other infectious diseases. The serological progress during treatment was evaluated in eight patients, and there was a relapse diagnosis in ten patients using the Pb B.339 strain antigen. The cut-off points for the serological tests were determined by a receiver operator characteristic curve. RESULTS: The DB and DID tests showed similar accuracy, but the DB identified lower antibody concentrations. Cross-reactions were absent in the DB assay. In the relapse diagnoses, DB exhibited much higher sensitivity (90%) than DID (30%). CONCLUSIONS: A DB assay is easier and faster than a DID test to be performed; DB and DID tests show the same accuracy, while blood qPCR is not recommended in the diagnosis at the time of admission; cross-reactions were not observed with other systemic diseases; DB and DID tests are useful for treatment monitoring PCM patients; and a DB assay is the choice for diagnosing relapse. These findings support the introduction of semi-quantitative DB assays in clinical laboratories.

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The diagnosis of human leptospirosis is mainly based on serological assays. Since the extraction by N-butanol has only been studied as an antigen for the diagnosis of cattle leptospirosis, this study aimed to investigate the feasibility of the N-butanol preparation for the diagnosis of human leptospirosis and compare it with sonicated and thermo-resistant antigens in IgM dot-blot test. Paired serum samples from 147 laboratory-confirmed leptospirosis cases were tested. The control group consisted of 148 serum samples from healthy individuals and nonleptospirosis cases. N-butanol antigens from serovar Copenhageni (ButC3) and serovar Patoc (ButP3) showed reactivity with antileptospiral antibodies from patients with confirmed leptospirosis. In the acute phase, sensitivities of IgM dot-blot assay with ButC3 and ButP3 antigens were 47.6% and 51.0%, respectively. In the convalescent phase, sensitivities were 95.9% (ButC3) and 93.2% (ButP3), and no significant differences were observed among the IgM dot-blot tests with other antigens. The specificity of the IgM dot-blot test with ButC3 antigen was good (92.6%), but with ButP3 (83.1%), it was significantly lower than with the other tests. The IgM dot-blot test described in this study is simple to perform and presents reliable visual results. Antigens prepared by N-butanol proved to be valuable diagnostic markers of leptospirosis.

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In this work, we report the caloric effect for an electronic system of the antidot type, modeled by combining a repulsive and attractive potential (parabolic confinement). In this system, we consider the action of a perpendicular external magnetic field and the possibility of having an Aharonov-Bohm flux (AB-flux) generated by a current passing through a solenoid placed inside the forbidden zone for the electron. The energy levels are obtained analytically, and the model is known as the Bogachek and Landman model. We propose to control the caloric response of the system by varying only the AB-flux, finding that, in the absence of an external magnetic field, the maximization of the effect always occurs at the same AB-flux intensity, independently of the temperature, while fixing the external magnetic field at a non-zero value breaks this symmetry and changes the point where the caloric phenomenon is maximized and is different depending on the temperature to which the process is carried. Our calculations indicate that using an effective electron mass of GaAs heterostructures and a trap intensity of the order of 2.896 meV, the modification of the AB-flux achieves a variation in temperature of the order of 1 K. Our analysis suggests that increasing the parabolic confinement twofold increases the effect threefold, while increasing the antidot size generates the reverse effect, i.e., a strong decrease in the caloric phenomenon under study. Due to the great diversity in technological applications that have antidots in electronics, the possibility of controlling their thermal response simply by varying the intensity of the internal current inside the solenoid (i.e., the intensity of AB-flux) can be a platform of interest for experimental studies.

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Among people living with HIV (PLHIV), progressive disseminated histoplasmosis (PDH) represents an important cause of mortality. Since antigen detection allows a rapid diagnosis and the instauration of a specific treatment this study aimed to evaluate the analytical performance of the Hcp100 dot blot, an in-house assay that detects the Histoplasma capsulatum 100-kilodalton antigen in urine and compare it with 2 commercially available assays the Histoplasma Urine Antigen Lateral Flow Assay (MVD-LFA) (MiraVista® Diagnostics) and the Clarus Histoplasma Galactomannan EIA (Clarus HGM) (IMMY). Urine specimens from 23 PLHIV with PDH, 13 patients with other infectious diseases, and 20 healthy individuals were tested. The Hcp100 dot blot showed higher sensitivity (87.0%), specificity (97.0%) and accuracy (92.9%) than the MVD-LFA (73.9%, 78.8%, and 76.8%, respectively) and the Clarus HGM (78.3%, 90.9%, and 85.7%, respectively). The Hcp100 dot blot had high analytical performance and would be a valuable screening tool for diagnosing PDH among PLHIV.

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Most laboratory tests to detect the presence of anti-SARS-CoV-2 antibodies use enzyme-linked immunosorbent assays (ELISA) or chemiluminescence immunoassays (CLIA); however, equipment for these immunoassays is unavailable in many areas of low- and middle-income countries. Rapid lateral flow immunoassay (LFIA) tests are an equipment-free option, but their high price may make them less suitable for conducting seroprevalence surveys. Here, we describe a simple dual antigen ELISA dot-blot test to detect anti-SARS-CoV-2 IgG antibodies with high sensitivity (94-98%) and specificity (92-100%), compared to commercially available ELISA and CLIA options. Additionally, this ELISA dot-blot test can be completed in one hour using minimal laboratory equipment. Importantly, this immunoassay is significantly more affordable than most LFIA tests available on the global market. The dot-blot strips may be stored for up to 7 days under freezing conditions. This ELISA dot-blot test is a cost-effective option for conducting seroprevalence screenings in areas lacking ELISA or CLIA facilities, compared to LFIA tests.

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The causative agent of human Q fever, Coxiella burnetii, is highly adapted to infect alveolar macrophages by inhibiting a range of host responses to infection. Despite the clinical and biological importance of this pathogen, the challenges related to genetic manipulation of both C. burnetii and macrophages have limited our knowledge of the mechanisms by which C. burnetii subverts macrophages functions. Here, we used the related bacterium Legionella pneumophila to perform a comprehensive screen of C. burnetii effectors that interfere with innate immune responses and host death using the greater wax moth Galleria mellonella and mouse bone marrow-derived macrophages. We identified MceF (Mitochondrial Coxiella effector protein F), a C. burnetii effector protein that localizes to mitochondria and contributes to host cell survival. MceF was shown to enhance mitochondrial function, delay membrane damage, and decrease mitochondrial ROS production induced by rotenone. Mechanistically, MceF recruits the host antioxidant protein Glutathione Peroxidase 4 (GPX4) to the mitochondria. The protective functions of MceF were absent in primary macrophages lacking GPX4, while overexpression of MceF in human cells protected against oxidative stress-induced cell death. C. burnetii lacking MceF was replication competent in mammalian cells but induced higher mortality in G. mellonella, indicating that MceF modulates the host response to infection. This study reveals an important C. burnetii strategy to subvert macrophage cell death and host immunity and demonstrates that modulation of the host antioxidant system is a viable strategy to promote the success of intracellular bacteria.

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BACKGROUND: Diagnosing progressive disseminated histoplasmosis (PDH) is still challenging in many countries where this disease is highly endemic. Definitive diagnosis is established by culture and/or by cytology/histopathology but both procedures have limited sensitivity and cultures are time-consuming. Antibodies detection by immunodiffusion has a low sensitivity in immunocompromised individuals. Commercially available antigen detection assays have high sensitivity in PDH cases; however, they are expensive and only performed in few laboratories. AIMS: To describe the potential use of a novel ELISA for antibodies testing and a dot blot assay for antigen testing for diagnosing PDH using the recombinant 100 kDa protein of Histoplasma capsulatum (Hcp100) and their polyclonal antibodies as novel reagents, respectively. METHODS: Serum and urine samples from a cohort of patients with HIV/AIDS and proven PDH were studied for the detection of anti-Hcp100 antibodies by ELISA and Hcp100 antigen by dot blot, respectively. Sensitivity, specificity and cross-reactions with other diseases were estimated for each assay and compared with those obtained using histoplasmin (HMN) as a reagent for antibodies detection by ELISA and immunodiffusion, and using a commercial antigenuria test. RESULTS: Antibodies detection by the Hcp100 ELISA demonstrated 78.6% sensitivity and 88.4% specificity, versus 85.7% sensitivity and 81.0% specificity for the HMN ELISA and 26.1% sensitivity and 100% specificity for the immunodiffusion assay. Antigen detection by the Hcp100 dot blot demonstrated 89.3% sensitivity and 97.0% specificity versus 82.1% sensitivity and 90.9% specificity for the commercial test. CONCLUSION: The immunoassays described herein based on Hcp100 would be a valuable screening tool for diagnosing PDH.

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A theoretical analysis of optical properties in a ZnS/CdS/ZnS core/shell/shell spherical quantum dot was carried out within the effective mass approximation. The corresponding Schrödinger equation was solved using the finite element method via the 2D axis-symmetric module of COMSOL-Multiphysics software. Calculations included variations of internal dot radius, the application of electric and magnetic fields (both oriented along z-direction), as well as the presence of on-center donor impurity. Reported optical properties are the absorption and relative refractive index change coefficients. These quantities are related to transitions between the ground and first excited states, with linearly polarized incident radiation along the z-axis. It is found that transition energy decreases with the growth of internal radius, thus causing the red-shift of resonant peaks. The same happens when the external magnetic field increases. When the strength of applied electric field is increased, the opposite effect is observed, since there is a blue-shift of resonances. However, dipole matrix moments decrease drastically with the increase of the electric field, leading to a reduction in amplitude of optical responses. At the moment impurity effects are activated, a decrease in the value of the energies is noted, significantly affecting the ground state, which is more evident for small internal radius. This is reflected in an increase in transition energies.

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A common task in bioinformatics is to compare DNA sequences to identify similarities between organisms at the sequence level. An approach to such comparison is the dot-plots, a 2-dimensional graphical representation to analyze DNA or protein alignments. Dot-plots alignment software existed before the sequencing revolution, and now there is an ongoing limitation when dealing with large-size sequences, resulting in very long execution times. High-Performance Computing (HPC) techniques have been successfully used in many applications to reduce computing times, but so far, very few applications for graphical sequence alignment using HPC have been reported. Here, we present G-SAIP (Graphical Sequence Alignment in Parallel), a software capable of spawning multiple distributed processes on CPUs, over a supercomputing infrastructure to speed up the execution time for dot-plot generation up to 1.68× compared with other current fastest tools, improve the efficiency for comparative structural genomic analysis, phylogenetics because the benefits of pairwise alignments for comparison between genomes, repetitive structure identification, and assembly quality checking.

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Leptospirosis is an infectious, zoonotic disease of worldwide distribution, the cause of which is infection by pathogenic Leptospira. In Chile, dairy cattle are recognized a significant source in the maintenance and transmission of this infection, which causes economic losses and represents an infection threat to workers in the dairy industry. The infection is underestimated in cattle, due to the lack of clinical, pathognomonic signs, as well as the low efficiency of current diagnostic techniques. In this study, we developed antigen ELISA and dot blot assays, based on polyclonal antibodies, to detect pathogenic Leptospira in the urine samples of dairy cattle. The proposed tests showed an acceptable diagnostic accuracy, based on an analytical sensitivity of 1·104 Leptospira per mL for ELISA, and 3.2·103 for dot blot. These results corresponded with those obtained by qPCR, and the use of urine samples allowed us to propose new diagnostic alternatives for pathogenic Leptospira infection at a low cost, which can provide information on active infection status, which is a key element in control programs both at individual and herd level.

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INTRODUCTION: Ampiginous Choroiditis is a rare posterior uveitis that combines clinical features of Acute Multifocal Posterior Placoid Pigment Epitheliopathy and Serpiginous Chorioretinitis. Its pathophysiology is poorly understood and further studies are necessary to understand which mechanisms start the immunologic reaction. CASE REPORT: The purpose of this article is to report a well-documented case of Ampiginous Choroiditis following in seven days a RT-PCR confirmed SARS-CoV-2 infection, suggesting that the infection might have contributed as a trigger. CONCLUSION: Timely diagnosis and correct treatment are paramount to improve the visual outcomes, and the patient had successful response to systemic steroids.

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Chronic Non-Communicable Diseases (NCDs) have been considered a global health problem, characterized as diseases of multiple factors, which are developed throughout life, and regardless of genetics as a risk factor of important relevance, the increase in mortality attributed to the disease to environmental factors and the lifestyle one leads. Although the reactive species (ROS/RNS) are necessary for several physiological processes, their overproduction is directly related to the pathogenesis and aggravation of NCDs. In contrast, dietary polyphenols have been widely associated with minimizing oxidative stress and inflammation. In addition to their antioxidant power, polyphenols have also drawn attention for being able to modulate both gene expression and modify epigenetic alterations, suggesting an essential involvement in the prevention and/or development of some pathologies. Therefore, this review briefly explained the mechanisms in the development of some NCDs, followed by a summary of some evidence related to the interaction of polyphenols in oxidative stress, as well as the modulation of epigenetic mechanisms involved in the management of NCDs.

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BACKGROUND: Successful tuberculosis (TB) treatment is necessary for disease control. The World Health Organization (WHO) has a target TB treatment success rate of ≥90%. We assessed whether the different types of unfavorable TB treatment outcome had different predictors. METHODS: Using data from Regional Prospective Observational Research for Tuberculosis-Brazil, we evaluated biological and behavioral factors associated with each component of unsuccessful TB outcomes, recently updated by WHO (death, loss to follow-up [LTFU], and treatment failure). We included culture-confirmed, drug-susceptible, pulmonary TB participants receiving standard treatment in 2015-2019. Multinomial logistic regression models with inverse probability weighting were used to evaluate the distinct determinants of each unsuccessful outcome. RESULTS: Of 915 participants included, 727 (79%) were successfully treated, 118 (13%) were LTFU, 44 (5%) had treatment failure, and 26 (3%) died. LTFU was associated with current drug-use (adjusted odds ratio [aOR] = 5.3; 95% confidence interval [CI], 3.0-9.4), current tobacco use (aOR = 2.9; 95% CI, 1.7-4.9), and being a person with HIV (PWH) (aOR = 2.0; 95% CI, 1.1-3.5). Treatment failure was associated with PWH (aOR = 2.7; 95% CI, 1.2-6.2) and having diabetes (aOR = 2.2; 95% CI, 1.1-4.4). Death was associated with anemia (aOR = 5.3; 95% CI, 1.4-19.7), diabetes (aOR = 3.1; 95% CI, 1.4-6.7), and PWH (aOR = 3.9; 95% CI, 1.3-11.4). Direct observed therapy was protective for treatment failure (aOR = 0.5; 95% CI, .3-.9) and death (aOR = 0.5; 95% CI, .2-1.0). CONCLUSIONS: The treatment success rate was below the WHO target. Behavioral factors were most associated with LTFU, whereas clinical comorbidities were correlated with treatment failure and death. Because determinants of unsuccessful outcomes are distinct, different intervention strategies may be needed to improve TB outcomes.

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Carbon dots (CDs) are nanometer-scale particles produced from carbon sources that exhibit fluorescence emission. The present work presents the synthesis and characterization of CDs, as well as the sensing studies for the determination of chloramphenicol (CAP). CAP is an antibiotic used in human medicine and agriculture, and its indiscriminate use and inappropriate disposal have caused damage to human health and the environment. The carbonaceous precursor used in the synthesis of CDs was 3,4-diaminobenzoic acid (3,4-DABA) through the hydrothermal method via domestic microwave irradiation. The first synthesis procedure was carried out in the presence of water/ethanol (a-CDs) and the second in the presence of 1 mol/L sodium hydroxide/ethanol (b-CDs). The CDs were initially characterized in terms of spectroscopic properties in the ultraviolet and visible region (UV-visible), Fourier-transform infrared (FTIR) spectra, Raman spectroscopy, and fluorescence emission spectroscopy. Sensing studies for the antibiotic C were performed by fluorescence suppression in the presence of a- and b-CDs, as well as the precursor 3,4-DABA. The a- and b-CDs presented similar values of linear range 0.00080-0.0050 mg/ml and limit of detection (LOD) = 0.00030 mg/ml (0.30 ppm) for CAP. Then, a- and b-CDs were embedded in Whatman and Mellita® filter paper, and CAP sensing was evaluated through UV light excitation.

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Leptospirosis is caused by bacteria of the genus Leptospira. More than 500,000 severe cases are reported annually, with a mortality rate of over 10%. Infection in humans usually occurs through direct or indirect contact with the urine of carrier animals. Reservoir animals do not present clinical signs of the acute disease, but renal colonization by Leptospira is frequent. Leptospirosis affects populations in both urban and rural areas, especially in tropical and subtropical climates areas. Conditions such as heavy rainfall and areas without sanitary services, favor the incidence and spread of leptospirosis. Humans are accidental hosts and may have asymptomatic manifestations or severe disease leading to death. The Leptospira genus harbors a wide variety of serovars, hindering the development of vaccine and early diagnosis, and consequently the control of the disease. The aim of this study was to identify Leptospira protein peptides conserved with immunogenic potential and capacity for recognition by antibodies present in human sera from diagnosed patients with leptospirosis. For this, five peptides were designed and selected in silico and analyzed by Dot-blot technique. The results demonstrated the five peptides were recognized by antibodies from human serum. The Pep 9 was recognized by two sera samples. In this study, the immunoinformatics tools were important to help in the peptides screening, and optimizing time and reducing financial expenses. The Dot-blot technique indicate to be effective for testing the recognition of epitopes that may induce an immune system response. The identification of peptides that are recognized by antibodies is a promising approach for the development of vaccines and diagnostic method for leptospirosis.

A leptospirose é causada por bactérias do gênero Leptospira. Anualmente são relatados mais de 500.000 casos graves, apresentando uma taxa de mortalidade superior a 10%. A infecção em humanos geralmente ocorre por contato direto ou indireto com a urina de animais portadores. Os humanos são hospedeiros acidentais e podem ter manifestações assintomáticas até condições graves evoluindo para óbito. Condições climáticas como chuvas intensas e condições sociais como áreas sem serviços sanitários, favorecem a incidência e disseminação da leptospirose. O gênero Leptospira alberga grande variedade de sorovares dificultando o desenvolvimento de uma vacina eficiente e diagnóstico precoce, e consequentemente o controle da doença. O presente estudo visa desenhar e identificar peptídeos de proteínas de Leptospira com potencial imunogênico e com capacidade de reconhecimento por anticorpos presentes em soros de pacientes diagnosticados com leptospirose. Para isso, cinco peptídeos foram desenhados e analisados in silício e por técnica de Dot-blot. Os resultados demonstraram a capacidade de reconhecimento dos cinco peptídeos testados frente às amostras de soro humano. Nesse estudo o uso da imunoinformática foi importante para auxiliar na escolha dos peptídeos, otimizando o tempo e diminuindo gastos financeiros. A técnica Dot-blot se mostrou eficaz para analisar o reconhecimento dos peptídeos de proteínas de Leptospira por anticorpos presentes nas amostras de soros analisadas. A identificação de peptídeos que sejam reconhecidos por anticorpos, é uma abordagem promissora para o desenvolvimento de vacinas e método de diagnostico para a leptospirose.

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Inflammasomes are cytosolic complexes composed of a Nod-like receptor, NLR, the adaptor protein, ASC, and a proteolytic enzyme, caspase-1. Inflammasome activation leads to caspase-1 activation and promotes functional maturation of IL-1ß and IL-18, two prototypical inflammatory cytokines. Besides, inflammasome activation leads to pyroptosis, an inflammatory type of cell death. Inflammasomes are vital for the host to cope with foreign pathogens or tissue damage. Herein, we show that quantum-dot-based iron oxide nanoparticles, MNP@QD, trigger NLRP3 inflammasome activation and subsequent release of proinflammatory interleukin IL-1ß by murine bone marrow-derived dendritic cells (BMDCs). This activation is more pronounced if these cells endocytose the nanoparticles before receiving inflammatory stimulation. MNP@QD was characterized by using imaging techniques like transmission electron microscopy, fluorescence microscopy, and atomic force microscopy, as well as physical and spectroscopical techniques such as fluorescence spectroscopy and powder diffraction. These findings may open the possibility of using the composite MNP@QD as both an imaging and a therapeutic tool.

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BACKGROUND: This manuscript describes a case of a patient with presumed ocular tuberculosis masquerading as multiple evanescent white dot syndrome. CASE PRESENTATION: A 32-year-old male patient presented with a complaint of reduced visual acuity in the left eye. Retinal fundus exam of the left eye revealed gray-whitish deep lesions predominantly nasal to the optic disc. The lesions were more clearly identifiable on fundus autofluorescence (FAF) imaging, fluorescein angiography (FA) and en face optical coherence tomography (OCT). FA also indicated retinal vasculitis and papillitis. Swept-source OCT B-scan demonstrated loss of the ellipsoid layer in the regions corresponding to the lesions detected by FAF. A positive tuberculin skin test (TST) confirmed presumed tuberculosis, and a related WDS diagnosis was made. Specific antituberculosis therapy was instituted with favorable anatomical recovery and visual outcome. CONCLUSION: Multiple evanescent white dot syndrome (MEWDS) may be manifestation of presumed ocular tuberculosis, and multimodal retinal exams can provide a better understanding of atypical diseases and their follow-up.

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The standardization and validation of a multiplex assay requires the combination of important parameters such as sensitivity and specificity, acceptable levels of performance, robustness, and reproducibility. We standardized a multiparametric Dot-blot aimed at the serological screening of paracoccidioidomycosis, histoplasmosis, and aspergillosis. A total of 148 serum were evaluated: 10 from healthy subjects, 36 from patients with paracoccidioidomycosis, 62 from patients with histoplasmosis, and 40 from patients with aspergillosis. It was found that the multiparametric Dot-blot showed a high percentage of cross-reactivity. However, when evaluated individually, in the serological screening of histoplasmosis, a good performance was observed when compared to the double immunodiffusion assay, considered the gold standard test, with 100% co-positivity and 83.3% co-negativity. The performance of serological screening for aspergillosis was not satisfactory when compared to double immunodiffusion, showing 71.4% co-positivity and 100% co-negativity. The evaluation of the stability of nitrocellulose membranes showed that membranes sensitized with H. capsulatum antigen remained stable for 90 days and those sensitized with A. fumigatus antigen for 30 days. We conclude that the use of crude antigens was not suitable for the standardization of the multiparametric Dot-blot assay, due to the high cross-reactivity, and that further tests should be performed with purified proteins (AU).

A padronização e validação de um ensaio multiplex requer a combinação de parâmetros importantes, como sensibilidade e especificidade, níveis aceitáveis de desempenho, robustez e reprodutibilidade. Este trabalho padronizou um Dot-blot multiparamétrico visando a triagem sorológica da paracoccidioidomicose, histoplasmose e aspergilose. Foram avaliadas 148 amostras de soro: 10 de indivíduos saudáveis, 36 de pacientes com paracoccidioidomicose, 62 de pacientes com histoplasmose e 40 de pacientes com aspergilose. Verificou-se que o Dot-blot multiparamétrico apresentou elevado percentual de reatividade cruzada. Entretanto, quando avaliado individualmente, na triagem sorológica da histoplasmose observou-se bom desempenho quando comparado ao ensaio de imunodifusão dupla, considerado o teste padrão ouro, com 100% de co-positividade e 83,3% de co-negatividade. O desempenho da triagem sorológica da aspergilose não foi satisfatório quando comparado a imunodifusão dupla, apresentando 71,4% de co-positividade e 100% de co-negatividade. A avaliação da estabilidade das membranas de nitrocelulose mostrou que membranas sensibilizadas com antígeno de H. capsulatum permaneceram estáveis por 90 dias e as sensibilizadas com antígeno de A. fumigatus, por 30 dias. Concluímos que o uso de antígenos brutos não foi adequado para a padronização do ensaio de Dot-blot multiparamétrico, devido ao alto índice de reatividade cruzada, e que novos testes devem ser realizados com proteínas purificadas (AU).

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The paper reports on a new mathematical model, starting with the original Hill equation which is derived to describe cell viability (V) while testing nanomaterials (NMs). Key information on the sample's morphology, such as mean size (⟨s⟩) and size dispersity (σ) is included in the new model via the lognormal distribution function. The new Hill-inspired equation is successfully used to fit MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) data from assays performed with the HepG2 cell line challenged by fluorine-containing graphene quantum dots (F:GQDs) under light (400-700 nm wavelength) and dark conditions. The extracted "biological polydispersity" (light: ⟨sMTT⟩=1.77±0.02 nm and σMTT=0.21±0.02); dark: ⟨sMTT⟩=1.87±0.02 nm and σMTT=0.22±0.01) is compared with the "morphological polydispersity" (⟨sTEM⟩=1.98±0.06 nm and σTEM=0.19±0.03), the latter obtained from TEM (transmission electron microscopy). The fitted data are then used to simulate a series of V responses. Two aspects are emphasized in the simulations: (i) fixing σ, one simulates V versus ⟨s⟩ and (ii) fixing ⟨s⟩, one simulates V versus σ. Trends observed in the simulations are supported by a phenomenological model picture describing the monotonic reduction in V as ⟨s⟩ increases (V~pa/(s)p-a; p and a are fitting parameters) and accounting for two opposite trends of V versus σ: under light (V~σ) and under dark (V~1/σ).