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1.
J Opt Soc Am A Opt Image Sci Vis ; 38(11): 1673-1680, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807029

RESUMO

A novel photoacoustic microscopy (PAM) structure, based on Haar wavelet patterns, is proposed in this paper. Its main goal is to mitigate the PAM imaging resolution and thus the time of its sampling process without compromising the image quality. Owing to the intrinsic nature of wavelet transform, this structure collects spatial and spectral components simultaneously, and this feature speeds up the sampling process by 33%. The selection of these patterns helps in better control of required conditions, such as multi-resolution imaging, to guarantee adequate image quality in comparison to previous microscopic structures. Simulation results prove the superior quality of the proposed approach (about 47% better peak signal-to-noise ratio) compared to the latest structures in this field, achieving a high-resolution and high-quality image.

2.
Anal Biochem ; 597: 113693, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32201137

RESUMO

The spherical sepharose CL-6B beads were activated by epichlorohydrin in different epoxy contents (80, 120 and 160 µmolepoxide/mLgel) and, l-histidine and imidazole as pseudo-affinity ligands were covalently immobilized to them. Some linkers with different length, (1,2-ethanediol diglycidyl ether and 1,4-butanediol diglycidyl ether) were synthesized for activation of sepharose and the activated sepharose beads modified with imidazole and the performance of these adsorbents in the purification of immunoglobulin G from bovine milk were evaluated. Among the l-histidine bearing adsorbents, higher adsorption of IgG (0.28 mg/mL) was obtained by adsorbent with the lower concentration of l-histidine. The highest amount of IgG adsorption (0.53 mg/mL) was obtained by imidazole bearing adsorbent with the highest amount of imidazole and Among the adsorbents with synthesized linkers, the adsorbent with 1,2-ethanediol diglycidyl ether showed better performance and was able to purify 0.25 mg/mL IgG with high purity. The synthesized pseudo-affinity adsorbents represented the abbility to purify immunoglobulin G in one-step process with high purity and efficiency.


Assuntos
Imidazóis/química , Imunoglobulina G/isolamento & purificação , Leite/química , Adsorção , Animais , Bovinos , Diglicerídeos/química , Etilenoglicol/química , Imunoglobulina G/química , Ligantes , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
3.
Anim Reprod Sci ; 163: 10-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26481046

RESUMO

Recent studies show that spermatogonial stem cells (SSCs) are able to colonize and form mature spermatozoa following transplantation into germ cell depleted testes of recipient males. Therefore, efficient ways for enrichment and gene transfer into SSCs provides a powerful tool for production of transgenic animals. In order to adapt the technique to goats, three issues were addressed: (i) enrichment of the undifferentiated spermatogonia including SSCs using magnetic activated cell sorting (MACS), (ii) lentiviral vector-mediated transduction of an enhanced green fluorescent protein (EGFP) transgene into enriched cells, and (iii) transplantation of transduced undifferentiated spermatogonia into the germ cell depleted testes of immune-suppressed mice to assess for migration and colony formation ability. Enriched cells were transduced by lentiviral vectors and subsequently analyzed for expression of THY1, PLZF, VASA, UCHL1 and BCL6B genes. Cells were also analyzed for GFP and PLZF by flow cytometry. Enriched transduced cells were transplanted into germ cell depleted mice testis. Quantitative analysis of transcripts revealed that MACS-enrichment significantly increased the expression of SSC-characteristic genes THY1, PLZF, VASA, UCHL1 and BCL6B compared to non-enriched population (P≤0.05). EGFP transduction did not affect the expression levels of SSC-characteristic genes. Flow cytometry revealed that 72% of transduced-enriched cells were positive for EGFP. Finally, transduced-enriched goat SSCs could colonize within the cells into the seminiferous tubules of germ cell depleted recipient mice at higher frequency than non-enriched cells. The results indicated that enrichment of goat undifferentiated spermatogonia by magnetic-activated cell sorting for THY1 antibody combined with lentiviral vector-mediated transduction has the potential to be used for production of transgenic goats.


Assuntos
Cabras , Espermatogônias/transplante , Células-Tronco/fisiologia , Animais , Anticorpos , Citometria de Fluxo , Regulação da Expressão Gênica , Proteínas de Fluorescência Verde , Masculino , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Túbulos Seminíferos , Antígenos Thy-1/imunologia
4.
Tunis Med ; 93(3): 187-9, 2015 Mar.
Artigo em Francês | MEDLINE | ID: mdl-26367410

RESUMO

UNLABELLED: Emergency physicians frequently encounter patients with thyroid disease. However, it is unusual for these thyroid disorders to create acute, life-threatening situations. Critical airway compression attributable to benign thyroid enlargement may occur suddenly and require urgent treatment. CASE REPORT: We report a case of pregnant women who was admitted for compressive goiter with laryngeal dyspnea, which required emergency total thyroidectomy. CONCLUSION: Urgent thyroidectomy in pregnant women can be performed if we respect the precautions.


Assuntos
Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/cirurgia , Bócio/complicações , Bócio/cirurgia , Tireoidectomia , Adulto , Feminino , Humanos , Gravidez , Complicações na Gravidez/cirurgia
5.
Theriogenology ; 80(8): 923-32, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23987985

RESUMO

Spermatogonial stem cells are unique cells of testes that can restore fertility upon transplantation into recipient testes. However, use of suitable markers for enrichment of these cells have important potential application. THY1, is an established conserved marker of spermatogonial stem cells in bovine, rodents, and primates, but there is no information available in goats. After three rounds of enzymatic digestion of prepubertal goat testicular tissues, undifferentiated spermatogonia positive for THY1 were isolated by magnetic-activated cell sorting and were used for immunocytochemistry, real-time polymerase chain reaction analysis for gene expression, protein expression, and transplantation into recipient mice. Immunocytochemical analyses showed that significantly higher percentage of THY1(+) cells were positive for PLZF and VASA when compared with unselected population. This result for PLZF was further confirmed at the protein level. Real-time polymerase chain reaction analysis revealed that expression of THY1, PLZF, VASA, BCL6B, and UCHL1 as SCCs characteristic genes in THY1(+) cells was significantly higher than in the initial population. Finally, transplantation of PKH26-labeled cells revealed that THY1(+) cells had higher capacity for colony formation when compared with unselected cells. In conclusion, the results provide indications that THY1 surface marker can be reliably used for enrichment of undifferentiated spermatogonial in the goats.


Assuntos
Diferenciação Celular/genética , Cabras/metabolismo , Espermatogônias/citologia , Antígenos Thy-1/metabolismo , Animais , Transplante de Células , Marcadores Genéticos , Masculino , Camundongos , Reação em Cadeia da Polimerase em Tempo Real , Espermatogênese , Espermatogônias/metabolismo , Espermatogônias/transplante , Testículo/citologia , Testículo/metabolismo
6.
N Am J Med Sci ; 5(11): 637-40, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24404541

RESUMO

BACKGROUND: Staphylococcus aureus is known as a powerful pathogen that causes various infections. Emergence of methicillin-resistant S. aureus (MSRA) is responsible for nosocomial and community-acquired infections worldwide. AIMS: The present study aimed to evaluate the performance and ability of eight different phenotypic and genotypic methods for the detection of MSRA. MATERIALS AND METHODS: A total of 186 S. aureus isolates were defined as methicillin-susceptible S. aureus (MSSA; 95) and MSRA (91) using polymerase chain reaction (PCR) as the gold standard. Susceptibility to methicillin was investigated using oxacillin, methicillin, cefotetan, cefoxitin, and cefmetazole disks, by oxacillin Adata Tab and strips. For all S. aureus isolates minimal inhibitory concentrations of oxacillin were determined using the broth microdilution method according to Clinical and Laboratory Standards Institute guidelines. RESULTS: Among the diagnostic methods studied, broth microdilution and the cefoxitin disk had the highest specificity (98.9 and 94.7%), sensitivity (100 and 98.9%), and concordance with PCR results (98.9 and 93.6%). The cefotetan and cefmetazole disks had the lowest concordance with PCR results. CONCLUSION: Our results suggest that microdilution and cefoxitin disk methods have high sensitivities compared with other methods for detection of MSRA. The cefoxitin disk method may be preferred in clinical laboratories because it is easy to perform and does not require special equipment.

7.
Cell Reprogram ; 14(2): 155-63, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22384929

RESUMO

Increased possibility of universality of ooplasmic reprogramming factors resulted in a parallel increased interest to use interspecies somatic cell nuclear transfer (iSCNT) to address basic questions of developmental biology and to improve the feasibility of cell therapy. In this study, the interactions between human somatic cells and ovine oocytes were investigated. Nuclear remodeling events were first observed 3 h post-iSCNT as nuclear swelling, chromosome condensation, and spindle formation. A time-dependent decrease in maturation promoting activity of inactivated reconstructs coincided with increased aberrations in chromosome and spindle organization of the newly developed embryos. The sequence and duration of nuclear remodeling events were irrespective of donor cell type used. Although the majority of the reconstituted embryos arrested before embryonic genome activation (8-16-cell) stage, less than 5% of them could progress beyond transcription-requiring developmental stage and formed blastocyst-like structures with distinct inner cell mass and trophectoderm at days 7 and 8 post-SCNT. Importantly, real-time assessment of three developmentally important genes (Oct4, Sox2, and Nanog) indicated their upregulation in iSCNT blastocysts. Blastocyst-derived outgrowths had alkaline phosphatase activity that was lost upon passage. Collectively, this study introduced ovine oocyte as a credible cytoplast for remodeling and reprogramming of human somatic cells back to the embryonic stage and provided a platform for further studies to unravel possible differences exist between reprogramming ability of oocytes of different mammalian species.


Assuntos
Desdiferenciação Celular/fisiologia , Reprogramação Celular/fisiologia , Desenvolvimento Embrionário , Técnicas de Transferência Nuclear , Oócitos/fisiologia , Adulto , Animais , Desdiferenciação Celular/genética , Núcleo Celular/metabolismo , Células Cultivadas , Reprogramação Celular/genética , Clonagem de Organismos/métodos , Células do Cúmulo/citologia , Células do Cúmulo/fisiologia , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Feminino , Fibroblastos/citologia , Fibroblastos/fisiologia , Humanos , Masculino , Oócitos/citologia , Oócitos/metabolismo , Carneiro Doméstico , Transplante Heterólogo
8.
Mol Reprod Dev ; 78(8): 576-84, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21721066

RESUMO

In this study, fibroblast cells were stably transfected with mouse POU5F1 promoter-driven enhanced green fluorescent protein (EGFP) to investigate the effect of S-adenosylhomocysteine (SAH), the reversible non-toxic inhibitor of DNA-methyltransferases (DNMTs), at different intervals post-fusion on in vitro development of cloned bovine embryos. Treatment with SAH for 12 hr resulted in 54.6 ± 7.7% blastocyst production, which was significantly greater than in vitro fertilized embryos (IVF: 37.2 ± 2.7%), cloned embryos treated with SAH for 72 hr (31.0 ± 7.6%), and control cloned embryos (34.6 ± 3.6%). The fluorescence intensities of the EGFP-POU5F1 reporter gene at all intervals of SAH treatment, except of 72 hr, were significantly higher than control somatic cell nuclear transfers (SCNT) embryos. The intensity of DNA-methylation in cloned embryos treated with SAH for 48 hr was similar to that of IVF embryos, and was significantly lower than the other SCNT groups. The levels of H3K9 acetylation in all SCNT groups were significantly lower than IVF embryos. Real-time PCR analysis of gene expression revealed significantly higher expression of POU5F1 in cloned versus IVF blastocysts. Neither embryo production method (SCNT vs. IVF) nor the SAH treatment interval affected expression of the BCL2 gene. Cloned embryos at all intervals of SAH treatment, except for 24 hr, had significantly increased VEGF transcript compared to IVF and control SCNT embryos. It was suggested that the time interval of DNMT inhibition may have important consequences on different in vitro features of bovine SCNT, and the improving effects of DNMT inhibition on developmental competency of cloned embryos are restricted to a specific period of time preceding de novo methylation.


Assuntos
Blastocisto/efeitos dos fármacos , Clonagem de Organismos/métodos , Embrião de Mamíferos/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , S-Adenosil-Homocisteína/farmacologia , Acetilação/efeitos dos fármacos , Animais , Blastocisto/metabolismo , Bovinos , Metilação de DNA/efeitos dos fármacos , Embrião de Mamíferos/fisiologia , Epigênese Genética , Feminino , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Histonas/metabolismo , Masculino , Camundongos , Microscopia de Fluorescência , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Transfecção
9.
Biochem Genet ; 48(11-12): 954-61, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20820903

RESUMO

RAPD markers were used to investigate population genetic parameters of an endangered partridge, Alectoris chukar, in four areas of Iran, as a part of a genetic conservation program. The aim of this study was to analyze the genetic similarity among these populations. Blood samples from 75 birds were used for DNA extraction and RAPD-PCR analysis of 67 loci, with 28 polymorphic bands (41.79%). The populations of Kalat-e-Nader and Mashhad were found to be closely related, as were the Torbat-e-Jaam and the Quchan populations. Mean heterozygosity for all populations was 0.4405 ± 0.0755. The results indicate that chukar partridge genetic diversity in Khorasan-e-Razavi province is sufficient and the amount of gene flow among populations is acceptable.


Assuntos
Galliformes/genética , Variação Genética , Animais , Espécies em Perigo de Extinção , Fluxo Gênico , Loci Gênicos , Irã (Geográfico) , Filogeografia , Polimorfismo Genético , Dinâmica Populacional , Técnica de Amplificação ao Acaso de DNA Polimórfico
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