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1.
Chem Mater ; 36(7): 3246-3258, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38617807

ABSTRACT

Tetrahedrite (Cu12Sb4S13) is an earth-abundant and nontoxic compound with prospective applications in green energy technologies such as thermoelectric waste heat recycling or photovoltaic power generation. A facile, one-pot solution-phase modified polyol method has been developed that produces high-purity nanoscale tetrahedrite products with exceptional stoichiometric and phase control. This modified polyol method is used here to produce phase-pure quaternary and quintenary tetrahedrite nanoparticles doped on the Cu-site with Zn, Fe, Ni, Mn, or Co. This is the first time that Cu-site codoped quintenary tetrahedrite and Mn-doped quaternary tetrahedrite have been produced by a solution-phase method. X-ray diffraction shows phase-pure tetrahedrite, while scanning and transmission electron microscopy show the size and morphology of the nanomaterials. Energy dispersive X-ray spectroscopy confirms nanoparticles have near-stoichiometric elemental compositions. Thermal stability of quintenary codoped tetrahedrite material is analyzed using thermogravimetric analysis, finding that codoping with Mn, Fe, Ni, and Zn increased thermal stability while codoping with cobalt decreased thermal stability. This is the first systematic study of the optical properties of quaternary and quintenary tetrahedrite nanoparticles doped on the Cu-site. Visible-NIR diffuse reflectance spectroscopy reveals that the quaternary and quintenary tetrahedrite nanoparticles have direct optical band gaps ranging from 1.88 to 2.04 eV. Data from thermal and optical characterization support that codoped tetrahedrite nanoparticles are composed of quintenary grains. This research seeks to enhance understanding of the material properties of tetrahedrite, leading to the optimization of sustainable, nontoxic, and high-performance photovoltaic and thermoelectric materials.

2.
Isr Med Assoc J ; 25(8): 559-563, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37574895

ABSTRACT

BACKGROUND: Jejunal disease is associated with worse prognosis in Crohn's disease. The added value of diffusion weighted imaging for evaluating jejunal inflammation related to Crohn's Disease is scarce. OBJECTIVES: To compare diffusion weighted imaging, video capsule endoscopy, and inflammatory biomarkers in the assessment of Crohn's disease involving the jejunum. METHODS: Crohn's disease patients in clinical remission were prospectively recruited and underwent magnetic resonance (MR)-enterography and video capsule endoscopy. C-reactive protein and fecal-calprotectin levels were obtained. MR-enterography images were evaluated for restricted diffusion, and apparent diffusion coefficient values were measured. The video capsule endoscopy-based Lewis score was calculated. Associations between diffusion weighted imaging, apparent diffusion coefficient, Lewis score, and inflammatory biomarkers were evaluated. RESULTS: The study included 51 patients, and 27/51 (52.9%) with video capsule endoscopies showed jejunal mucosal inflammation. Sensitivity and specificity of restricted diffusion for video capsule endoscopy mucosal inflammation were 59.3% and 37.5% for the first reader, and 66.7% and 37.5% for the second reader, respectively. Diffusion weighted imaging was not statistically associated with jejunal video capsule endoscopy inflammation (P = 0.813). CONCLUSIONS: Diffusion weighted imaging was not an effective test for evaluation of jejunal inflammation as seen by video capsule endoscopy in patients with quiescent Crohn's disease.


Subject(s)
Capsule Endoscopy , Crohn Disease , Humans , Crohn Disease/diagnosis , Crohn Disease/diagnostic imaging , Capsule Endoscopy/methods , Jejunum/diagnostic imaging , Diffusion Magnetic Resonance Imaging/methods , Inflammation/diagnosis , Magnetic Resonance Imaging , Biomarkers/analysis
3.
Sci Rep ; 13(1): 10399, 2023 06 27.
Article in English | MEDLINE | ID: mdl-37369809

ABSTRACT

The wide use of genomic information has enabled the identification of lethal recessive alleles that are the major genetic causes of reduced conception rates, longer calving intervals, or lower survival for live-born animals. This study was carried out to screen the Nellore cattle genome for lethal recessive haplotypes based on deviation from the expected population homozygosity, and to test SNP markers surrounding the lethal haplotypes region for association with heifer rebreeding (HR), post-natal mortality (PNM) and stayability (STAY). This approach requires genotypes only from apparently normal individuals and not from affected embryos. A total of 62,022 animals were genotyped and imputed to a high-density panel (777,962 SNP markers). Expected numbers of homozygous individuals were calculated, and the probabilities of observing 0 homozygotes was obtained. Deregressed genomic breeding values [(G)EBVs] were used in a GWAS to identify candidate genes and biological mechanisms affecting HR, STAY and PNM. In the functional analyses, genes within 100 kb down and upstream of each significant SNP marker, were researched. Thirty haplotypes had high expected frequency, while no homozygotes were observed. Most of the alleles present in these haplotypes had a negative mean effect for PNM, HR and STAY. The GWAS revealed significant SNP markers involved in different physiological mechanisms, leading to harmful effect on the three traits. The functional analysis revealed 26 genes enriched for 19 GO terms. Most of the GO terms found for biological processes, molecular functions and pathways were related to tissue development and the immune system. More phenotypes underlying these putative regions in this population could be the subject of future investigation. Tests to find putative lethal haplotype carriers could help breeders to eliminate them from the population or manage matings in order to avoid homozygous.


Subject(s)
Genomics , Polymorphism, Single Nucleotide , Cattle/genetics , Animals , Female , Haplotypes/genetics , Genotype , Phenotype , Alleles , Genome-Wide Association Study
4.
J Allergy Clin Immunol ; 150(6): 1525-1533, 2022 12.
Article in English | MEDLINE | ID: mdl-35760390

ABSTRACT

BACKGROUND: Much of our understanding of the targets of IgE comes from studies of allergy, though little is known about the natural immunogenic targets seen after parasitic worm infections. OBJECTIVE: We used human monoclonal antibodies (mAbs) for an unbiased and comprehensive characterization of the immunodominant antigens targeted by IgE in conditions like allergy or helminth infection that are associated with elevated levels of IgE. METHODS: Using human hybridoma technology to immortalize IgE encoding B-cells from peripheral blood of subjects with filarial infections and elevated IgE, we generated naturally occurring human IgE mAbs. B-cell cultures were screened in an unbiased manner for IgE production without regard to specificity. Isolated IgE mAbs were then tested for binding to Brugia malayi somatic extracts using ImmunoCAP, immunoblot, and ELISA. Immunoprecipitation followed by mass spectrometry proteomics was used to identify helminth antigens that were then expressed in Escherichia coli for IgE binding characterization. RESULTS: We isolated 56 discrete IgE mAbs from 7 individuals with filarial infections. From these mAbs, we were able to definitively identify 19 filarial antigens. All IgE mAbs targeted filarial excreted/secretory proteins, including a family of previously uncharacterized proteins. Interestingly, the transthyretin-related antigens acted as the dominant inducer of the filaria-specific IgE antibody response. These filaria-specific IgE mAbs were potent inducers of anaphylaxis when passively administered to human FcεRI-expressing mice. CONCLUSIONS: We generated human hybridomas secreting naturally occurring helminth-specific IgE mAbs from filarial-infected subjects. This work provides much-needed insight into the ontogeny of helminth-induced immune response and IgE antibody response.


Subject(s)
Helminths , Hypersensitivity , Humans , Animals , Mice , Antibodies, Monoclonal
5.
J Immunol ; 205(8): 1999-2007, 2020 10 15.
Article in English | MEDLINE | ID: mdl-32907999

ABSTRACT

IgE Abs drive the symptoms of allergic disease upon cross-linking allergens on mast cells or basophils. If the IgE binding sites on the allergens could be identified, it may be useful for creating new forms of immunotherapy. However, direct knowledge of the human IgE (hIgE) epitopes is limited because of the very low frequency of IgE-producing B cells in blood. A new hybridoma technology using human B cells from house dust mite-allergic patients was used to identify four Der p 2-specific hIgE mAbs. Their relative binding sites were assessed and compared by immunoassays with three previously studied murine IgG mAbs. Immunoassays showed that the recognition of Der p 2 by the first three hIgE was inhibited by a single murine IgG, but the fourth hIgE recognized a different epitope from all the other mAbs. The functional ability of the hIgE that bind different epitopes to cross-link Der p 2 was demonstrated in a mouse model of passive systemic anaphylaxis. Nuclear magnetic resonance analyses of Der p 2 in complex with IgG and IgE Abs were used to identify specific residues in the epitopes. To our knowledge, the combination of immunoassays to distinguish overlapping epitopes and nuclear magnetic resonance analyses to identify specific residues involved in Ab binding provided the first epitope mapping of hIgE mAbs to an allergen. The technologies developed in this study will be useful in high-resolution mapping of human epitopes on other Ags and the design of improved therapeutics.


Subject(s)
Antibodies, Monoclonal/immunology , Antigens, Dermatophagoides/immunology , Arthropod Proteins/immunology , Epitope Mapping , Epitopes/immunology , Immunoglobulin E/immunology , Humans
6.
Issues Ment Health Nurs ; 40(4): 297-303, 2019 Apr.
Article in English | MEDLINE | ID: mdl-31038405

ABSTRACT

Parent caregivers support the health and well-being of their adult children with schizophrenia. As a result, parent caregivers spend vast amounts of time providing care, which necessitates changes to their relationships and lives. In this qualitative study, the experiences of parent caregivers for adult children with schizophrenia were explored. Interpretive Description guided the study design, and data were collected through interviews with 12 English-speaking participants. Data were analyzed according to conventional content analysis. The themes "Uncertainty, Change, and Challenges" and "The Meaning of It All" help to articulate the participants' experiences. Overall, the participants reported tremendous distress in their roles. This was compounded by difficulties accessing and navigating the healthcare system and interactions with police. Effective strategies are needed to help parent caregivers cope within their role and gain access to timely and appropriate care.


Subject(s)
Adult Children/psychology , Caregivers/psychology , Parents/psychology , Schizophrenia/therapy , Schizophrenic Psychology , Adaptation, Psychological , Adult , Aged , Emotions , Female , Humans , Male , Middle Aged , Qualitative Research , Stress, Psychological , Young Adult
7.
JCI Insight ; 3(20)2018 10 18.
Article in English | MEDLINE | ID: mdl-30333320

ABSTRACT

Sensitization to Aspergillus species is associated with allergic respiratory diseases. Allergen immunotherapy with nonstandardized Aspergillus extracts is commonly used as therapy in these patients. Unfortunately, no method exists to measure the relevant allergen protein content in diagnostic and therapeutic extracts. Thus, there is a critical need for Aspergillus extract standardization. We hypothesized that development of Aspergillus-specific human IgE mAbs would allow for the characterization of the relevant human allergenic epitopes among currently available commercial Aspergillus fumigatus extracts. Patients with allergic bronchopulmonary mycosis were recruited from Vanderbilt University Medical Center. IgE antibody-secreting B cells were grown and immortalized using human hybridoma techniques first described here. Twenty-six human Aspergillus-reactive IgE mAbs were used as capture and detection reagents to characterize the Aspergillus allergen content of commercial extracts. We found extreme variability in the specificity and quantity of their protein targets. Just 4 mAbs reacted with all available extracts, and only 1 of 4 extracts contained the major allergen Asp f 1. This degree of variability will almost certainly affect the efficacy of these reagents when used in diagnosis and treatment. Human IgE mAbs represent an innovative tool for the evaluation of relevant human allergenic epitopes, which may assist in future development and long-term standardization of mold extracts.


Subject(s)
Allergens/administration & dosage , Aspergillus fumigatus/immunology , Desensitization, Immunologic/methods , Invasive Pulmonary Aspergillosis/drug therapy , Monitoring, Immunologic/methods , Adolescent , Aged, 80 and over , Allergens/immunology , Antibodies, Monoclonal/blood , Antibodies, Monoclonal/immunology , Antigens, Fungal/immunology , Desensitization, Immunologic/standards , Epitopes/immunology , Feasibility Studies , Humans , Hybridomas , Immunoglobulin E/blood , Immunoglobulin E/immunology , Invasive Pulmonary Aspergillosis/blood , Invasive Pulmonary Aspergillosis/immunology , Male , Reproducibility of Results , Young Adult
8.
Article in English | MEDLINE | ID: mdl-24855402

ABSTRACT

OBJECTIVE: We studied the prevalence of endocrine dysfunction in subjects with idiopathic Parkinson's disease (IPD) on newer dopaminergic agents (DA). DA are also used in endocrine hypersecretory states in small doses and we hypothesized that endocrine dysfunction was likely in IPD where DA were used in comparatively much higher dosage. PATIENTS AND METHODS: Twenty-five subjects with IPD, established on DA, were recruited to this cross-sectional study. We measured insulin-like growth factor-1, prolactin, luteinizing hormone, follicle stimulating hormone, thyroid function, oestradiol or testosterone and cortisol levels following a short synacthen test. RESULTS: We studied 18 males and 7 females, whose median age was 72 years, and whose median time from diagnosis, and duration of treatment was 27 months (interquartile range 17-45 and 13-39 months, respectively). (1) Endocrine tests were normal in 19 of 25 subjects at recruitment. Minor abnormalities reverted to normal on repeat testing in three of six with initial abnormalities; two had persistent abnormalities and the third subject could not be further investigated. Therefore, 22 of 24 (92%) with IPD on DA therapy had normal endocrine profiles. (2) The cortisol response to ACTH was normal in 24 of 25 subjects (96%). (3) Eleven subjects (44%) had isolated PRL suppression. There were no differences between the suppressed PRL and "normal" PRL groups. However, a higher number of them were on non-ergoline-derived DA (83% vs 31%; P < 0.05). CONCLUSIONS: We have demonstrated that newer non-ergoline DA therapy caused only minimal endocrine perturbations in subjects with IPD. Their clinical significance can only be speculative currently. The cortisol response to ACTH was normal in almost all but a significant minority had suppressed prolactin levels.

9.
J Int Soc Prev Community Dent ; 4(Suppl 3): S204-8, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25625080

ABSTRACT

AIM: To evaluate the accuracy of working length determination of an electronic apex locator, IPEX, on vital uninfected teeth and teeth with radiographic evidence of periapical lesions. MATERIALS AND METHODS: Twenty vital and uninfected teeth and 16 teeth with a single canal and matured apices and having radiographic evidence of periapical lesions of 5-10 mm were taken for this study. Access cavities were prepared and pulp was considered to be vital if bleeding was present upon entering the chambers. No. 15 k-type file was used to determine the working length. X-rays were taken to determine the working length using Ingle's method, followed by determination using the electronic apex locator, IPEX. Teeth were then observed under 45 × magnification using stereomicroscope. No 15 k-type file was maneuvered till the emergence of the tip was seen and the real length of the tooth was thus measured in the instrument up to 0.5 mm accuracy using stereomicroscope. RESULTS: The data were duly collected and entered, and the statistical analysis was done using Student's t test. In uninfected teeth, IPEX was found to be more reliable than Ingle's radiographic technique, but this was not statistically significant. In case of teeth with radiographic evidence of periapical lesions, the radiographic method appeared to be relatively more dependable; however, this difference was not statistically significant. CONCLUSION: For rendering effective root canal procedure, both radiographs and electronic apex locators have important roles to play.

10.
Acta amaz ; 39(2): 349-360, 2009. graf, tab
Article in English | LILACS | ID: lil-522381

ABSTRACT

Forest regrowth occupies an extensive and increasing area in the Amazon basin, but accurate assessment of the impact of regrowth on carbon and nutrient cycles has been hampered by a paucity of available allometric equations. We develop pooled and species-specific equations for total aboveground biomass for a study site in the eastern Amazon that had been abandoned for 15 years. Field work was conducted using randomized branch sampling, a rapid technique that has seen little use in tropical forests. High consistency of sample paths in randomized branch sampling, as measured by the standard error of individual paths (14 percent), suggests the method may provide substantial efficiencies when compared to traditional procedures. The best fitting equations in this study used the traditional form Y=a×DBHb, where Y is biomass, DBH is diameter at breast height, and a and b are both species-specific parameters. Species-specific equations of the form Y=a(BA×H), where Y is biomass, BA is tree basal area, H is tree height, and a is a species-specific parameter, fit almost as well. Comparison with previously published equations indicated errors from -33 percent to +29 percent would have occurred using off-site relationships. We also present equations for stemwood, twigs, and foliage as biomass components.


Florestas secundárias ocupam uma área extensa e crescente na bacia Amazônica, porém determinações acuradas do impacto dessas florestas nos ciclos de carbono e nutrientes têm sido dificultadas pelo número reduzido de equações alométricas. Neste estudo, nós desenvolvemos equações em nível de comunidade e espécies individuais para estimar a biomassa total da parte aérea de uma floresta secundária com 15 anos de idade na Amazônia oriental. O trabalho de campo utilizou amostragem aleatória de ramos, que é uma técnica rápida, porém pouco utilizada em florestas tropicais. Baseada no erro padrão da série de segmentos individuais (14 por cento), a consistência da série de segmentos totais amostrados foi considerada elevada, sugerindo que o método pode ser eficiente em comparação com procedimentos tradicionais. Os melhores ajustes foram obtidos com a equação tradicional Y=a×DBHb, onde Y é a biomassa, DBH é o diâmetro à altura do peito, e a e b são parâmetros para cada espécie arbórea. Ajustes razoáveis também foram alcançados com equações da forma Y=a(BA×H), onde Y é a biomassa, BA é a área basal, H é a altura e a é um parâmetro específico para cada espécie arbórea. Comparações com equações disponíveis na literatura indicaram uma faixa de erro provável de -33 por cento a +29 por cento usando-se relações desenvolvidas para outros sítios. Nós também apresentamos equações para os seguintes componentes da biomassa da parte aérea: tronco, ramos e folhas.


Subject(s)
Rainforest , Latent Class Analysis
11.
Acta amaz ; 33(4): 619-630, Dec. 2003. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-574679

ABSTRACT

O presente trabalho descreve o ingresso e a mortalidade em uma floresta em diferentes estágios sucessionais, no município de Castanhal, Pará. A área de estudo está localizada na Estação Experimental da Universidade Federal Rural da Amazônia. As parcelas foram implantadas em áreas de florestas sucessionais de diferentes idades (4, 8 e 12 anos). Nas florestas sucessionais de 4 e 8 anos foram utilizadas quatro parcelas de 10m x 10m e na floresta de 12 anos foram, 12 parcelas de 10m x 10m. Realizaram duas medições de todos os indivíduos com DAP>1cm, em intervalos de 12 meses, nas florestas sucessionais de 4 e 8 anos; e intervalo de 18 meses na floresta de 12 anos. Foram calculadas as taxas de ingresso e de mortalidade. Na floresta de 4 anos o ingresso foi maior que a mortalidade. Nas florestas sucessionais de 8 e 12 anos as densidades diminuíram, perdendo mais indivíduos por mortalidade do que ganhando por ingresso. Lacistema pubescens, Myrcia silvatica, Vismia guianensis, Rollinia exsucca e Miconia ciliata apresentaram muitos indivíduos mortos nas florestas estudadas.


The present work describe recruitment and mortality in a forest in different successional stages in Castanhal, Pará. The study area is located at the Experimental Research Station of the Universidade Federal Rural da Amazônia. Twelve 10m x 10m study plots were established in a 12-year-old secondary forest, and four 10m x 10m study plots were demarcated in a 4-year-old and an 8-year-old secondary forest. We measured diameter and height of all individuals with DBH>1cm at a 12-month interval in the 4 and 8-year-old stands, and an 18-month interval in the 12-year-old stand. Using this inventory data we calculated recruitment and mortality rates. In the 4-year-old forest, recruitment was greater than mortality, while in the 8 and 12-year-old forests experienced net mortality, as density declined over the measurement interval. Lacistema pubescens, Myrcia sylvatica, Vismia guianensis, Rollinia exsucca and Miconia ciliata displayed the greatest number of dead individuals in the studied successional forests.


Subject(s)
Mortality , Forestry , Patient Selection , Rainforest
12.
Acta amaz ; 33(4): 563-582, Dec. 2003. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-574675

ABSTRACT

O objetivo deste trabalho foi estudar a sucessão florestal pela análise florística e estrutural de floresta em três estágios sucessionais (4, 8 e 12 anos), localizadas no município de Castanhal-PA. Consideraram-se duas classes de DAP: Classe I (DAP>1cm) e classe II (DAP<1cm). Para a classe I, foram utilizadas 12 parcelas de 10m x 10m, na floresta sucessional de 12 anos e 4 parcelas de 10m x 10m nas de 4 e 8 anos. Para a classe II, foram utilizadas 48 subparcelas de 1m x 1m na floresta de 12 anos e 16 subparcelas de 1m x 1m nas de 4 e 8 anos. Na classe I, foram identificadas 18, 30 e 73 espécies e 12, 18 e 21 indivíduos/ha, respectivamente, nas florestas de 4, 8 e 12. Na classe II, foram identificadas 17, 21 e 62 espécies; e 50, 26 e 47 indivíduos/m², também, respectivamente, nas florestas de 4, 8 e 12 anos. Na classe I, Lacistema pubescens, Vismia guianensis e Myrcia silvatica apresentaram maiores abundâncias e dominâncias relativas. Na classe II, Lacistema pubescens, Vismia guianensis, Miconia ciliata, Myrcia bracteatae Banara guianensis também apresentaram elevado número de indivíduos. Myrcia silvatica apresentou maior abundância nos três estágios. A similaridade entre as floresttas na classe I foi de aproximadamente 60 por cento e na classe II, 42 por cento. Os resultados sugerem que as florestas apresentaram características de três fases de desenvolvimento da floresta: fase de iniciação (4 anos), fase de exclusão (8 anos) e o início da fase de reiniciação do sub-bosque (12 anos).


The objective of this study is to understand secondary forest succession through florisitc and structural analysis of a forest in three successional stages (4, 8 and 12 years) located in Castanhal in the state of Pará. This study considers wood species divided into two DBH classes: class I (DBH>1cm) and class II (DBH<1cm). Class I individuals were measured in twelve 10m x 10m plots in the 12-year-old successional forest, and in four 10 x 10 m plots in the 4 and 8-year-old secondary forest stands. Class II individuals were measured in 48 subplots of 1m x 1m in the 12-year-old forest stand, and in 16 subplots in the 4 and 8-year-old forest stands. In Class I, 18, 30 and 73 species were identified; and were found 12, 18 and 21 individuals/ha in the 4, 8 and 12-year-old forests, respectively. In class II, 17, 21 and 62 species were identified; and were found 50, 26 and 47 individuals/m² in the 4, 8 and 12-year-old forests, respectively. For class I, Lacistema pubescens, Vismia guianensis and Myrcia sylvatica demonstrated the greatest abundance and relative dominance. In class II, Lacistema pubescens, Vismia guianensis, Miconia ciliata, Myrcia bracteata and Banara guianensis also displayed an elevated number of individuals. Myrcia sylvatica presented the greatest abundance in the three successional stages. Similarity among plots was approximately 60 percent for class I and 42 percent for class II. The results showed the forest with three stages of successional development: initiation phase (4 years), exclusion phase (8 years), and the beginning of the understory reinitiation phase (12 years).


Subject(s)
Forests , Forestry
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