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2.
PLoS One ; 18(8): e0289370, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37552704

RESUMO

The male genitalia of Surazomus algodoal Ruiz & Valente, 2017 are described. Since this is the first attempt to describe male genitalia in the schizomids, we propose new terminology to describe the sclerites of the male genital chamber in the order. We believe that the male genitalia may provide a large set of characters for taxonomic research in schizomids, as the female genitalia have proven to do. The setae and other cuticular structures were investigated using light and scanning electron microscopy (SEM). The female of S. algodoal is described for the first time, including the genitalia, and we highlight the sexual dimorphism present in the species. We also present descriptions of: 1) microtrichia, with respect to their presence/length/distribution, 2) cuticular sensilla, glandular openings and other cuticular structures, proposing new terminology, 3) setae of the pedipalpal trochanter and tarsus. Some changes on the terminology of setae of pedipalpal tibia are also given. These advances may be useful for description in other schizomids. The pygidial glands, mostly ignored in modern papers, were assessed and commented upon.


Assuntos
Aracnídeos , Animais , Feminino , Masculino , Genitália Masculina , Genitália , Sensilas/ultraestrutura , Microscopia Eletrônica de Varredura
3.
Nanoscale ; 15(17): 7854-7869, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37060148

RESUMO

Several vaccines against COVID-19 use a recombinant SARS-CoV-2 receptor-binding domain (RBD) as antigen, making the purification of this protein a key step in their production. In this work, citrate-coated magnetic iron oxide nanoparticles were evaluated as nano adsorbents in the first step (capture) of the purification of recombinant RBD. The nanoparticles were isolated through coprecipitation and subsequently coated with sodium citrate. The citrate-coated nanoparticles exhibited a diameter of 10 ± 2 nm, a hydrodynamic diameter of 160 ± 3 nm, and contained 1.9 wt% of citrate. The presence of citrate on the nanoparticles' surface was confirmed through FT-IR spectra and thermogravimetric analysis. The crystallite size (10.1 nm) and the lattice parameter (8.3646 Å) were determined by X-ray diffraction. In parallel, RBD-containing supernatant extracted from cell culture was exchanged through ultrafiltration and diafiltration into the adsorption buffer. The magnetic capture was then optimized using different concentrations of nanoparticles in the purified supernatant, and we found 40 mg mL-1 to be optimal. The ideal amount of nanoparticles was assessed by varying the RBD concentration in the supernatant (between 0.113 mg mL-1 and 0.98 mg mL-1), which resulted in good capture yields (between 83 ± 5% and 94 ± 4%). The improvement of RBD purity after desorption was demonstrated by SDS-PAGE and RP-HPLC. Furthermore, the magnetic capture was scaled up 100 times, and the desorption was subjected to chromatographic purifications. The obtained products recognized anti-RBD antibodies and bound the ACE2 receptor, proving their functionality after the developed procedure.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Vacinas contra COVID-19 , Ácido Cítrico , Espectroscopia de Infravermelho com Transformada de Fourier , Citratos
4.
Microorganisms ; 10(8)2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36014102

RESUMO

Infections remain a major cause of morbidity and mortality among hematopoietic stem cell transplant (HSCT) recipients. Unlike Epstein-Barr Virus (EBV) and Human Cytomegalovirus (HCMV), Human Herpesvirus (HHV) 6, HHV7 and HHV8 are not routinely monitored in many centers, especially in the pediatric population of low-medium income countries. We screened EBV, HCMV, HHV6, HHV7 and HHV8 in 412 leukocytes-plasma paired samples from 40 pediatric patients assisted in a tertiary hospital in Mexico. Thirty-two underwent allo-HSCT, whereas eight received auto-HSCT. Overall viral detection frequencies in allo- and auto-HSCT were: EBV = 43.7% and 30.0%, HCMV = 5.0% and 6.7%, HHV6 = 7.9% and 20.0% and HHV7 = 9.7% and 23.3%. HHV8 was not detected in any sample. Interestingly, HHV6 and HHV7 were more frequent in auto-HSCT, and HHV6 was observed in all episodes of multiple detection in auto-HSCT patients. We found EBV DNA in plasma samples, whereas HCMV, HHV6 and HHV7 DNA were predominantly observed in leukocytes, indicative of their expansion in cellular compartments. We also found that IL-1ß, IL-2, IL-6 and IL-8 were significantly increased in episodes in which multiple viruses were simultaneously detected, and samples positive for EBV DNA and graft-versus-host disease had a further increase of IL-1ß and IL-8. In conclusion, the EBV, HCMV, HHV6 and HHV7 burdens were frequently detected in allo- and auto-HSCT, and their presence associated with systemic inflammation.

5.
Curr Zool ; 68(1): 81-92, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35169631

RESUMO

Males can control female reproduction using genital plugs to impede access by rivals. In social bees, ants, and wasps, plugging may involve traumatic mating, with females being harmed. In stingless bees, chances are that plugs may promote ovarian activan, and are thought to ensure single mating-a general tendency among the social Hymenoptera. However, understanding on relationships between mating plugs, traumatic mating, and mating systems in stingless bees remains limited. To address this, we (1) compared mated queens of 7 Neotropical species to understand the patterns of copulatory marks in females and (2) compared pre- and post-mating genitalia of males and females in Melipona fasciculata to depict plug functional morphology. Data revealed an unprecedented consequence of mating in stingless bees: the characteristic marks left by mating plugs on female abdomens and the inferences that can be made from them. To our surprise, in 1 species M. fasciculata we found that queens retain the plug long after mating, and may carry it for the rest of their lives. All the other 6 species retained the plug for only a short period. Remated queens were only found in M. seminigra, whose multiple copulatory marks match previous findings of polyandry in this species. Our study shows that queens can remate, and suggests that male genital morphology may determine in part the time persistence of plugs. We conclude that traumatic mating plugs do not fully prevent remating in stingless bees and that mating systems are not uniform in this group. Nonetheless, exceptional cases of facultative polyandry in social insects-for example, when mating plugs fail-may confirm a general tendency for single mating in close link with efficient mating plugs.

6.
Int J Mol Sci ; 23(3)2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35163649

RESUMO

Yin-Yang transcription factor 1 (YY1) is involved in tumor progression, metastasis and has been shown to be elevated in different cancers, including leukemia. The regulatory mechanism underlying YY1 expression in leukemia is still not understood. Bioinformatics analysis reveal three Hypoxia-inducible factor 1-alpha (HIF-1α) putative binding sites in the YY1 promoter region. The regulation of YY1 by HIF-1α in leukemia was analyzed. Mutation of the putative YY1 binding sites in a reporter system containing the HIF-1α promoter region and CHIP analysis confirmed that these sites are important for YY1 regulation. Leukemia cell lines showed that both proteins HIF-1α and YY1 are co-expressed under hypoxia. In addition, the expression of mRNA of YY1 was increased after 3 h of hypoxia conditions and affect several target genes expression. In contrast, chemical inhibition of HIF-1α induces downregulation of YY1 and sensitizes cells to chemotherapeutic drugs. The clinical implications of HIF-1α in the regulation of YY1 were investigated by evaluation of expression of HIF-1α and YY1 in 108 peripheral blood samples and by RT-PCR in 46 bone marrow samples of patients with pediatric acute lymphoblastic leukemia (ALL). We found that the expression of HIF-1α positively correlates with YY1 expression in those patients. This is consistent with bioinformatic analyses of several databases. Our findings demonstrate for the first time that YY1 can be transcriptionally regulated by HIF-1α, and a correlation between HIF-1α expression and YY1 was found in ALL clinical samples. Hence, HIF-1α and YY1 may be possible therapeutic target and/or biomarkers of ALL.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Fator de Transcrição YY1/metabolismo , Adolescente , Linhagem Celular Tumoral , Criança , Pré-Escolar , Regulação Neoplásica da Expressão Gênica , Humanos , Lactente , Recém-Nascido
7.
Zootaxa, v. 5124, n. 4, p. 431–457, abr. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4299

RESUMO

Huriini Simon, 1901 currently consists of six genera and 17 species, distributed exclusively in South America. In this work, the huriine genus Guriurius Marta, Bustamante, Ruiz & Rodrigues, gen. nov. is proposed with two new species herein described: Guriurius minuano Marta, Bustamante, Ruiz & Rodrigues, sp. nov. (type species) and Guriurius nancyae Marta, Bustamante, Ruiz & Rodrigues, sp. nov. The female of Atelurius segmentatus Simon, 1901 is described and illustrated for the first time. Scoturius dipterioides Perger & Rubio, 2018 is transferred to Atelurius Simon, 1901 due to the morphological similarity of copulatory ducts of epigyne, and Hurius pisac Galiano, 1985 is transferred to Simonurius Galiano, 1988 due to the similarities in body shape and female genitalia. Simonurius campestratus (Simon, 1901) is synonymized with Simonurius quadratarius (Simon, 1901). The interpretation of genitalic characters in Huriini is discussed. In addition, we provide new distributional records for Admesturius bitaeniatus (Simon, 1901), Ad. mariaeugeniae Bustamante & Scioscia, 2014, Ad. schajovskoyi Galiano, 1988, At. segmentatus Simon, 1901, Scoturius tigris Simon, 1901, Hurius aeneus (Mello-Leitão, 1941), and Simonurius gladifer (Simon, 1901). Except for Urupuyu Ruiz & Maddison, 2015, all huriine genera are rediagnosed in the new context of tribe and genus composition.

9.
Zootaxa ; 5057(2): 241-259, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34811211

RESUMO

Gypogyna Simon, 1900 is revised. Three species are recognized and diagnosed. The type species, Gypogyna forceps Simon, 1900, is redescribed and recorded from several localities in South America. Gypogyna amazonica Ruiz sp. nov. is described based on a male from Manaus, Brazil. Gypogyna mexicana Ruiz Bustamante sp. nov. is described based on specimens of both sexes from the state of Jalisco, Mexico. In addition, some comments on cheliceral dentiton and genital morphology are discussed.


Assuntos
Aranhas , Distribuição Animal , Animais , Feminino , Masculino , Tamanho do Órgão
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