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1.
Biochem Biophys Res Commun ; 734: 150735, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39357336

RESUMEN

Chronic alcohol (ethanol) use is increasing in the United States and has been linked to numerous health issues in multiple organ systems including neurological dysfunction and diseases. Ethanol toxicity is mainly driven by the metabolite acetaldehyde, which is generated through three pathways: alcohol dehydrogenase (ADH2), catalase (CAT), and cytochrome P450 2E1 (CYP2E1). ADH2, while the main ethanol clearance pathway in the liver, is not expressed in the mammalian brain, resulting in CAT and CYP2E1 driving local metabolism of ethanol in the central nervous system. CYP2E1 is known to generate reactive metabolites and reactive oxygen species and localizes to the mitochondria (mtCYP2E1) and endoplasmic reticulum (erCYP2E1). We sought to understand the consequences of mtCYP2E1 and erCYP2E1 in the nervous system during acute ethanol exposure. To answer this question, we generated transgenic Caenorhabditis elegans roundworms expressing human CYP2E1 in the mitochondria, endoplasmic reticulum, or both and exposed them to ethanol. We found that at lower concentrations, wild-type and mtCYP2E1-expressing worms had a small but significant inhibition of locomotion, whereas the erCYP2E1-expressing worms showed protection from this inhibition. At higher doses, all strains had reduced locomotion, but the erCYP2E1-expressing worms recovered faster than wild-type controls. CYP2E1 expression, regardless of organellar targeting, reduced mitochondrial respiration in response to ethanol. Similarly, transgenic expression of CYP2E1 in either organelle in PC-12 rat neuronal cell lines sensitized them to ethanol-induced cell death. Together, these findings suggest that subcellular localization of CYP2E1 impacts behavioral effects of ethanol and should be further studied in the mammalian central nervous system.

2.
Vox Sang ; 112(3): 279-287, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28220510

RESUMEN

BACKGROUND AND OBJECTIVES: Variant RHD genes associated with the weak D phenotype can result in complete or partial D-epitope expression on the red cell. This study examines the genetic classification in Australian blood donors with a weak D phenotype and correlates RHD variants associated with the weak D phenotype against D-epitope profile. MATERIALS AND METHODS: Following automated and manual serology, blood samples from donors reported as 'weak D' (n = 100) were RHD genotyped by a commercial SNP-typing platform and Sanger sequencing. Two commercial anti-D antibody kits were used for extended serological testing for D-epitope profiles. RESULTS: Three samples had wild-type RHD exonic sequences, and 97 samples had RHD variants. RHD*weak D type 1, RHD*weak D type 2 or RHD*weak D type 3 was detected in 75 donors. The remaining 22 samples exhibited 17 different RHD variants. One donor exhibited a novel RHD*c.939+3A>C lacking one D-epitope. Weak D types 1·1, 5, 15, 17 and 90 showed a partial D-epitope profile. CONCLUSION: The array of RHD variants detected in this study indicated diversity in the Australian donor population that needs to be accommodated for in future genotyping strategies.


Asunto(s)
Donantes de Sangre/estadística & datos numéricos , Sistema del Grupo Sanguíneo Rh-Hr/genética , Alelos , Australia , Secuencia de Bases , Transfusión Sanguínea , ADN/química , ADN/aislamiento & purificación , ADN/metabolismo , Epítopos/inmunología , Epítopos/metabolismo , Exones , Frecuencia de los Genes , Genotipo , Humanos , Isoanticuerpos/sangre , Fenotipo , Polimorfismo de Nucleótido Simple , Globulina Inmune rho(D)/sangre , Análisis de Secuencia de ADN , Pruebas Serológicas
3.
Opt Express ; 24(3): 3127-36, 2016 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-26906877

RESUMEN

Temporal overlapping of ultra-short and focussed laser pulses is a particularly challenging task, as this timescale lies orders of magnitude below the typical range of fast electronic devices. Here we present an optical technique that allows for the measurement of the temporal delay between two focussed and ultra-short laser pulses. This method is virtually applicable to any focussing geometry and relative intensity of the two lasers. Experimental implementation of this technique provides excellent quantitative agreement with theoretical expectations. The proposed technique will prove highly beneficial for high-power multiple-beam laser experiments.

4.
Vox Sang ; 109(3): 296-303, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25900316

RESUMEN

BACKGROUND AND OBJECTIVES: Duffy blood group phenotypes can be predicted by genotyping for single nucleotide polymorphisms (SNPs) responsible for the Fy(a) /Fy(b) polymorphism, for weak Fy(b) antigen, and for the red cell null Fy(a-b-) phenotype. This study correlates Duffy phenotype predictions with serotyping to assess the most reliable procedure for typing. MATERIALS AND METHODS: Samples, n = 155 (135 donors and 20 patients), were genotyped by high-resolution melt PCR and by microarray. Samples were in three serology groups: 1) Duffy patterns expected n = 79, 2) weak and equivocal Fy(b) patterns n = 29 and 3) Fy(a-b-) n = 47 (one with anti-Fy3 antibody). RESULTS: Discrepancies were observed for five samples. For two, SNP genotyping predicted weak Fy(b) expression discrepant with Fy(b-) (Group 1 and 3). For three, SNP genotyping predicted Fy(a) , discrepant with Fy(a-b-) (Group 3). DNA sequencing identified silencing mutations in these FY*A alleles. One was a novel FY*A 719delG. One, the sample with the anti-Fy3, was homozygous for a 14-bp deletion (FY*01N.02); a true null. CONCLUSION: Both the high-resolution melting analysis and SNP microarray assays were concordant and showed genotyping, as well as phenotyping, is essential to ensure 100% accuracy for Duffy blood group assignments. Sequencing is important to resolve phenotype/genotype conflicts which here identified alleles, one novel, that carry silencing mutations. The risk of alloimmunisation may be dependent on this zygosity status.


Asunto(s)
Algoritmos , Sistema del Grupo Sanguíneo Duffy/genética , Receptores de Superficie Celular/genética , Alelos , Secuencia de Bases , Estudios de Asociación Genética , Humanos , Datos de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Transición de Fase , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN
5.
Vox Sang ; 108(1): 52-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25092430

RESUMEN

BACKGROUND AND OBJECTIVES: An Australian Caucasian blood donor consistently presented a serology profile for the Duffy blood group as Fy(a+b+) with Fy(a) antigen expression weaker than other examples of Fy(a+b+) red cells. Molecular typing studies were performed to investigate the reason for the observed serology profile. MATERIAL AND METHODS: Blood group genotyping was performed using a commercial SNP microarray platform. Sanger sequencing was performed using primer sets to amplify across exons 1 and 2 of the FY gene and using allele-specific primers. RESULTS: The propositus was genotyped as FY*A/B, FY*X heterozygote that predicted the Fy(a+b+(w) ) phenotype. Sequencing identified the 265T and 298A variants on the FY*A allele. This link between FY*A allele and 265T was confirmed by allele-specific PCR. CONCLUSION: The reduced Fy(a) antigen reactivity is attributed to a FY*A allele-carrying 265T and 298A variants previously defined in combination only with the FY*B allele and associated with weak Fy(b) antigen expression. This novel allele should be considered in genotyping interpretative algorithms for generating a predicted phenotype.


Asunto(s)
Donantes de Sangre , Sistema del Grupo Sanguíneo Duffy/genética , Polimorfismo de Nucleótido Simple , Algoritmos , Alelos , Australia , Genotipo , Técnicas de Genotipaje/métodos , Humanos , Datos de Secuencia Molecular , Fenotipo , Población Blanca/genética
6.
Vox Sang ; 107(1): 90-6, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24372289

RESUMEN

The International Society of Blood Transfusion Working Party on red cell immunogenetics and blood group terminology convened during the International congress in Cancun, July 2012. This report details the newly identified antigens in existing blood group systems and presents three new blood group systems.


Asunto(s)
Antígenos de Grupos Sanguíneos/clasificación , Terminología como Asunto , Antígenos de Grupos Sanguíneos/genética , Antígenos de Grupos Sanguíneos/inmunología , Humanos , Inmunogenética , Sociedades Científicas
9.
Sci Rep ; 13(1): 18125, 2023 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-37872247

RESUMEN

Polyploid cells contain more than two copies of each chromosome. Polyploidy has important roles in development, evolution, and tissue regeneration/repair, and can arise as a programmed polyploidization event or be triggered by stress. Cancer cells are often polyploid. C. elegans nematodes are typically diploid, but stressors such as heat shock and starvation can trigger the production of tetraploid offspring. In this study, we utilized a recently published protocol to generate stable tetraploid strains of C. elegans and compared their physiological traits and sensitivity to two DNA-damaging chemotherapeutic drugs, cisplatin and doxorubicin. As prior studies have shown, tetraploid worms are approximately 30% longer, shorter-lived, and have a smaller brood size than diploids. We investigated the reproductive defect further, determining that tetraploid worms have a shorter overall germline length, a higher rate of germ cell apoptosis, more aneuploidy in oocytes and offspring, and larger oocytes and embryos. We also found that tetraploid worms are modestly protected from growth delay from the chemotherapeutics but are similarly or more sensitive to reproductive toxicity. Transcriptomic analysis revealed differentially expressed pathways that may contribute to sensitivity to stress. This study reveals phenotypic consequences of whole-animal tetraploidy that make C. elegans an excellent model for ploidy differences.


Asunto(s)
Caenorhabditis elegans , Tetraploidía , Animales , Caenorhabditis elegans/genética , Ploidias , Poliploidía , Diploidia
10.
bioRxiv ; 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37333126

RESUMEN

Polyploid cells contain more than two copies of each chromosome. Polyploidy has important roles in development, evolution, and tissue regeneration/repair, and can arise as a programmed polyploidization event or be triggered by stress. Cancer cells are often polyploid. C. elegans nematodes are typically diploid, but stressors such as heat shock and starvation can trigger the production of tetraploid offspring. In this study, we utilized a recently published protocol to generate stable tetraploid strains of C. elegans and compared their physiological traits and sensitivity to two DNA-damaging chemotherapeutic drugs, cisplatin and doxorubicin. As prior studies have shown, tetraploid worms are approximately 30% longer, shorter-lived, and have a smaller brood size than diploids. We investigated the reproductive defect further, determining that tetraploid worms have a shorter overall germline length, a higher rate of germ cell apoptosis, more aneuploidy in oocytes and offspring, and larger oocytes and embryos. We also found that tetraploid worms are modestly protected from growth delay from the chemotherapeutics but are similarly or more sensitive to reproductive toxicity. Transcriptomic analysis revealed differentially expressed pathways that may contribute to sensitivity to stress. Overall, this study reveals the phenotypic consequences of whole-animal tetraploidy in C. elegans.

11.
Biophys J ; 102(11): 2424-32, 2012 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-22713557

RESUMEN

We study the drying of stratum corneum, the skin's outermost layer and an essential barrier to mechanical and chemical stresses from the environment. Even though stratum corneum exhibits structural features across multiple length-scales, contemporary understanding of the mechanical properties of stratum corneum is based on the assumption that its thickness and composition are homogeneous. We quantify spatially resolved in-plane traction stress and deformation at the interface between a macroscopic sample of porcine stratum corneum and an adherent deformable elastomer substrate. At length-scales greater than a millimeter, the skin behaves as a homogeneous elastic material. At this scale, a linear elastic model captures the spatial distribution of traction stresses and the dependence of drying behavior on the elastic modulus of the substrate. At smaller scales, the traction stresses are strikingly heterogeneous and dominated by the heterogeneous structure of the stratum corneum.


Asunto(s)
Desecación , Fenómenos Fisiológicos de la Piel , Estrés Fisiológico , Animales , Módulo de Elasticidad/fisiología , Colorantes Fluorescentes/metabolismo , Sus scrofa
12.
Proc Natl Acad Sci U S A ; 105(47): 18501-6, 2008 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-19011094

RESUMEN

Two types of blast colonies can be stimulated to develop in semisolid agar cultures of murine bone marrow cells. Typically, these are either multicentric colonies stimulated by stem cell factor (SCF) plus interleukin-6 (IL-6) or dispersed colonies stimulated by Flt3 ligand (FL) plus IL-6. Both types of blast colony-forming cells (BL-CFCs) can generate large numbers of lineage-committed granulocyte-macrophage progenitor cells and exhibit some capacity for self-generation and the formation of eosinophil and megakaryocyte progenitor cells. However, the two populations of BL-CFCs are largely distinct and partially separable by fluorescence-activated cell sorting and are distinguished by differing capacity to form granulocyte-committed progeny. Both types of BL-CFCs can generate dendritic cells and small numbers of lymphocytes but the FL-responsive BL-CFCs have a greater capacity to form both B and T lymphocytes. Both types of blast colonies offer remarkable opportunities to analyze multilineage commitment at a clonal level in vitro.


Asunto(s)
Células Madre Hematopoyéticas/citología , Animales , Linfocitos B/citología , Diferenciación Celular , Células Cultivadas , Interleucina-6/fisiología , Proteínas de la Membrana/fisiología , Ratones , Ratones Endogámicos , Factor de Células Madre/fisiología , Linfocitos T/citología
13.
Euro Surveill ; 15(40)2010 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-20946757

RESUMEN

Assessment of the severity of disease due to the 2009 pandemic influenza A(H1N1) in Australian states and territories has been hampered by the absence of denominator data on population exposure. We compared antibody reactivity to the pandemic virus using haemagglutination inhibition assays performed on plasma specimens taken from healthy adult blood donors (older than 16 years) before and after the influenza pandemic that occurred during the southern hemisphere winter. Pre-influenza season samples (April ­ May 2009, n=496) were taken from donation collection centres in North Queensland (in Cairns and Townsville); post-outbreak specimens (October ­ November 2009, n=779) were from donors at seven centres in five states. Using a threshold antibody titre of 40 as a marker of recent infection, we observed an increase in the influenza-seropositive proportion of donors from 12% to 22%, not dissimilar to recent reports of influenza A(H1N1)-specific immunity in adults from the United Kingdom. No significant differences in seroprevalence were observed between Australian states, although the ability to detect minor variations was limited by the sample size. On the basis of these figures and national reporting data, we estimate that approximately 0.23% of all individuals in Australia exposed to the pandemic virus required hospitalisation and 0.01% died. The low seroprevalence reported here suggests that some degree of prior immunity to the virus, perhaps mediated by broadly reactive T-cell responses to conserved influenza viral antigens, limited transmission among adults and thus constrained the pandemic in Australia.


Asunto(s)
Anticuerpos Antivirales/sangre , Donantes de Sangre/estadística & datos numéricos , Subtipo H1N1 del Virus de la Influenza A/inmunología , Gripe Humana/epidemiología , Estudios Seroepidemiológicos , Adolescente , Adulto , Distribución por Edad , Anciano , Anticuerpos Antivirales/inmunología , Australia/epidemiología , Femenino , Pruebas de Inhibición de Hemaglutinación , Humanos , Gripe Humana/sangre , Gripe Humana/virología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Pandemias , Adulto Joven
15.
ISBT Sci Ser ; 11(2): 118-122, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29093749

RESUMEN

The Working Party has met twice since the last report: in Seoul, South Korea 2014, and in London, UK 2015, both in association with the International Society of Blood Transfusion (ISBT) Congress. As in previous meetings, matters pertaining to blood group antigen nomenclature were discussed. Eleven new blood group antigens were added to seven blood group systems. This brings the current total of blood group antigens recognized by the ISBT to 346, of which 308 are clustered within 36 blood groups systems. The remaining 38 antigens are currently unassigned to a known blood group system.

16.
Am J Surg Pathol ; 5(2): 179-91, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7223929

RESUMEN

Useful morphologic criteria for frozen section diagnosis of pancreatic and periampullary carcinoma were established by prospective review of 64 frozen sections in this region, with permanent section correlation and patient follow-up. These were divided into three major and five minor criteria based on frequency of occurrence and reproducibility. Major criteria were: 1) nuclear size variation of 4:1 or greater between ductal epithelial cells, 2) incomplete ductal lumens, and 3) disorganized duct distribution. Minor criteria, less frequently and reproducibly observed but valuable diagnostic aids, included: 1) huge, irregular epithelial nucleoli; 2) necrotic glandular debris; 3) glandular mitoses; 4) glands unaccompanied by connective tissue stroma within smooth muscle bundles (periampullary biopsies); and 5) perineural invasion. Combined application of both major and minor criteria is especially helpful in cases complicated by chronic pancreatitis.


Asunto(s)
Adenocarcinoma/patología , Neoplasias Pancreáticas/patología , Adenocarcinoma/complicaciones , Adulto , Anciano , Ampolla Hepatopancreática/patología , Neoplasias de los Conductos Biliares/patología , Femenino , Estudios de Seguimiento , Secciones por Congelación , Humanos , Hiperplasia/patología , Masculino , Persona de Mediana Edad , Conductos Pancreáticos/patología , Neoplasias Pancreáticas/complicaciones , Pancreatitis/complicaciones , Pancreatitis/patología , Estudios Prospectivos
17.
Hum Immunol ; 16(1): 38-51, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-2423486

RESUMEN

Class II molecules were isolated from consanguineous HTCs (DR1-DRw8) by sequential immunoprecipitation with the monoclonal antibodies 7.3.19.1 (anti-DRw52-like), B8.11.2 (anti-DR backbone), and 7.5.10.1 (anti-HLA class II backbone). Depending upon the DR-serotype of the cell line used, two or three class II antigen families, distinct in molecular weight, could be isolated (see Hum Immunol 9:221, 1984). Immunoprecipitated class II molecules were treated with NaNase and then analyzed on 1D-IEF gels. Each HLA class II antigen family contained two alpha chains conserved in pI. Furthermore, the various haplotypes show distinct electrophoretic beta chain patterns. The number of beta chain charge configurations detected varies from 2 to 5, depending upon the antigen family or haplotype studied. Some of these chains have a pI which is specific for a given class II serotype whereas other beta chain pIs are invariant and shared among more antigen families or haplotypes.


Asunto(s)
Antígenos de Histocompatibilidad Clase II/análisis , Anticuerpos Monoclonales/inmunología , Epítopos/análisis , Antígenos HLA-DR , Subtipos Serológicos HLA-DR , Antígeno HLA-DR1 , Antígeno HLA-DR2 , Antígeno HLA-DR3 , Antígeno HLA-DR4 , Antígeno HLA-DR5 , Antígeno HLA-DR7 , Antígenos de Histocompatibilidad Clase II/inmunología , Punto Isoeléctrico
18.
Am J Clin Pathol ; 68(5): 606-10, 1977 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-920660

RESUMEN

Reported is a case of lymphoma which was preceded for nine years by an apparently reactive lymphadenopathy. Original slides of the multiple lymphoid tissue samples are reviewed, with emphasis on the gradually increasing numbers of mitoses, atypical histiocytes, and eosinophils, suggestive of malignant transformation. The scarcity of such cases in the literature prompts this report.


Asunto(s)
Ganglios Linfáticos/patología , Linfoma/patología , Lesiones Precancerosas/patología , Adulto , Femenino , Histiocitos/patología , Humanos , Ganglios Linfáticos/ultraestructura , Linfoma/diagnóstico , Linfoma/ultraestructura
19.
Arch Dermatol ; 116(8): 925-8, 1980 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6447482

RESUMEN

A case of follicular occlusion disease with notably increased and abnormal elastic tissue and transepidermal elimination of elastic fibers is reported. This combination of findings has traditionally been regarded as unique to elastosis perforans serpiginosa and, to our knowledge, has not previously been described in other follicular diseases. It is hypothesized that the histopathologic changes seen in this case might be a nonspecific secondary alteration in the dermis caused by long-standing chronic inflammation and/or repeated exposure of the dermis to follicular contents.


Asunto(s)
Acné Vulgar/patología , Tejido Elástico/patología , Enfermedades de las Glándulas Sudoríparas/patología , Acné Vulgar/complicaciones , Adulto , Humanos , Inflamación/diagnóstico , Masculino , Piel/patología , Supuración , Enfermedades de las Glándulas Sudoríparas/complicaciones
20.
Pathology ; 20(3): 271-4, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3144700

RESUMEN

The estimation of plasma alanine aminotransferase (ALT) has been proposed as a surrogate test to identify potential non-A, non-B hepatitis carriers in blood donor populations. This report describes an ALT screening procedure which uses wells of microtitration trays as reactant vessels. The method utilizes a rate reading photometer, is economical and conveniently fits into the routine workflow. Within-batch and between-batch precision was 4.1% and 6.3% at enzyme concentrations of 49 IU/I. Results of testing 29,675 healthy blood donors gave values which ranged between 1.0 IU/I and 214 IU/I. A study of 762 donations showed a significant difference in mean ALT values between males and females (p less than 0.01). When a cut-off value of 46 IU/I was used, 2.5 percent of donations were considered unsuitable for transfusion. The medico-legal implications that may arise from the introduction of this screening test into the routine work flow are discussed.


Asunto(s)
Alanina Transaminasa/sangre , Donantes de Sangre , Portador Sano/diagnóstico , Pruebas Enzimáticas Clínicas , Hepatitis C/diagnóstico , Hepatitis Viral Humana/diagnóstico , Femenino , Humanos , Masculino , Queensland , Factores de Tiempo
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