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1.
Pathogens ; 13(3)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38535579

RESUMO

The members of the Chlamydiaceae family are important pathogens that infect a wide range of vertebrate hosts, including humans. Among them, Chlamydia psittaci, historically considered as an avian agent, has recently been identified in livestock, primarily sheep and cattle, but also in horses, with the infection being linked to reproductive disorders, such as abortion, absorption of embryos, stillbirth, and the birth of weak foals. Much less is known about chlamydial infections in the Sardinian equine population. This study aimed to identify the chlamydial diversity in genital samples from asymptomatic Sardinian horses. However, some horses had a previous history of reproductive disorders, i.e., abortion and infertility. A total of 60 horses (39 mares and 21 stallions) were opportunistically recruited from 17 equine farms in central-northern Sardinia. Vaginal and uterine swabs from mares and urethral swabs and seminal fluid from stallions were sampled for the presence of chlamydial DNA. Samples from environments where the horses lived were also tested for the detection of Chlamydia spp. Eight vaginal swabs (8/39; 20%), two uterine swabs (2/27; 7%), two seminal fluid samples (2/20; 10%), and one urethral swab (1/21; 4.7%) were found to be positive for Chlamydia spp. by PCR analysis. In addition, results from environmental samples showed the presence of Chlamydia spp. in three environmental swabs (3/8; 37.5%) and five water samples (5/16; 31.2%). Sequencing results revealed that strains here identified were 99-100% similar to members belonging to the Chlamydiaceae family, including C. abortus, C. psittaci, and uncultured Chlamydia genotypes. ompA species-specific PCR performed on samples was found to be positive after 16S rRNA amplification gave positive results for C. psittaci. These results reveal the first presence of C. psittaci in the genital tract of horses and in the environment in Sardinia and indicate that this pathogen could be the prevailing cause of infertility and abortion in the tested equines. However, these findings need further proof and highlight the importance of adopting a 'One Health' approach to control the presence of this zoonotic bacteria in domestic animals in order to understand its impact on people exposed to the infection risk.

2.
Acta Trop ; 252: 107151, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367944

RESUMO

Cystic Echinococcosis (CE), caused by the larval form of Echinococcus granulosus sensu lato, is a neglected zoonosis still threatening public health worldwide. In Italy different epidemiological scenarios were reported depending on the geographical area and associated socio-economic activities. Although in northern Italy the occurrence of E. granulosus is considered sporadic, in the southern regions and, particularly in Sardinia, CE prevalence reaches high levels. We analysed CE cysts collected from infected sheep from various areas of mainland Italy and the Sardinia island, with the main objective to investigate intergenotypic and intragenotypic variations at national level. CE cysts were collected from slaughtered sheep following post mortem inspection at local abattoirs. Total genomic DNA was extracted and amplification and sequencing of the partial mitochondrial genes nad5 and cox1 were performed. A Bayesian phylogenetic tree was estimated on a nad5 dataset (n = 260) composed of E. granulosus samples from this study (n = 126) and all the nad5 haplotypes available in GenBank (n = 134). In addition, haplotype network, diversity and neutrality analysis were performed on nad5 and cox1 sequences of Italian origin obtained in this study. E. granulosus sensu stricto (s.s.) was found to be the only Echinococcus species infecting sheep in Italy, mainly represented by G1 genotype (76 %) and, to a lower extent, by G3 genotype (24 %). Phylogenetic analyses revealed 40 nad5 and 33 cox 1 haplotypes, and the presence of two founder haplotypes, belonging to G1 and G3 genotype, showing 100 % similarity with DNA sequences from different geographic regions. The lack of geographical segregation, high haplotype and low nucleotide diversity coupled with significant negative values of Tajima's D and Fu's Fs observed in this study indicated high genetic variation and demographic expansion of E. granulosus s.s. in Italy.


Assuntos
Cistos , Equinococose , Echinococcus granulosus , Animais , Ovinos , Echinococcus granulosus/genética , Filogenia , Teorema de Bayes , Variação Genética , Equinococose/epidemiologia , Equinococose/veterinária , Haplótipos , Genótipo , Itália/epidemiologia
3.
Vet Sci ; 10(1)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36669060

RESUMO

Piroplasmoses are tick-borne diseases caused by hemoprotozoan parasites of veterinary and public health significance. This study focuses on the molecular identification and characterization of species belonging to the Theileria/Babesia genera in 152 blood samples, collected from 80 horses and 72 cattle from several farms in Sardinia, by targeting the 18S rRNA gene. The PCR results highlighted that 72% of the samples were positive for Theileria/Babesia spp., with a rate of infection of 68% and 75% for the horses and cattle, respectively. Sequencing and the BLASTn analysis showed that the 18S rRNA generated in this study has 99-100% homology with the B. bigemina, T. orientalis/sergenti/buffeli, T. equi and T. annulata strains isolated from different hosts worldwide. These findings improve the knowledge on Babesia and Theileria infections in domestic mammals and confirm the significant prevalence of piroplasmosis among subclinical and carrier animals throughout the island. Furthermore, the presence of T. annulata, reported for the first time in the study area, expands the repertoire of pathogens already detected in Sardinia. Our results gather updates on the diversity and distribution of piroplasms in Sardinia and suggest the need to develop procedures to improve animal and public health safety.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36361084

RESUMO

Chlamydia psittaci is an intracellular bacterium belonging to the Chlamydiaceae family. It is the ethiologic agent of psittacosis, an occupational zoonotic disease that mainly concerns people who work in close contact with birds that represent the main infection route for human transmission. In Italy, information about this disease is lacking. This study is the first case of avian chlamydiosis reported from a pet shop in Sardinia, Italy. Chlamydia psittaci detected in psittacine birds by molecular analysis, direct immunofluorescence test together with anatomo-pathological observed lesions, highlighted the importance of focusing the attention over this underestimated zoonosis in a "One Health" prospective.


Assuntos
Doenças das Aves , Chlamydophila psittaci , Psittaciformes , Psitacose , Animais , Humanos , Psitacose/epidemiologia , Psitacose/veterinária , Psitacose/microbiologia , Chlamydophila psittaci/genética , Estudos Prospectivos , Doenças das Aves/epidemiologia , Psittaciformes/microbiologia , Aves , Surtos de Doenças/veterinária
5.
Biology (Basel) ; 11(4)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35453692

RESUMO

Glioblastoma is a brain tumour frequently used as an experimental model to exploit innovative therapeutic approaches due to its high lethality and refractoriness to therapies. Part of these innovative anticancer therapies address cytoskeletal microtubules (MTs) since specific tubulin post-translational modifications (PTMs) are considered markers of tumour plasticity. In vitro studies, which traditionally employ two-dimensional (2D) culture systems, are now being replaced by three-dimensional (3D) systems that more closely mimic in vivo physiological conditions and allow a better understanding of the signalling between cells. In this work, we compared 2 liquid base 3D methods for the generation of spheroids from C6 rat glioma cells (RGCs) using 30 µL of liquid marble (LM) or the hanging drops (HDs), which contained 2 different cell numbers (5000 or 15,000). After 24 or 48 h of in vitro culture (IVC), the morphology of the spheroids was observed and the behaviour of the two main tubulin PTMs, tyrosinated α-tubulin (Tyr-T) and acetylated α-tubulin (Ac-T), was evaluated by fluorescence and Western blot (WB). RGCs spontaneously formed spherical agglomerates more rapidly in the LM than in the HD system. Cell density influenced the size of the spheroids, which reached a larger size (> of 300 µm Ø), with 15,000 cells compared to 5000 cells (150 µm Ø). Moreover, an increase in Tyr-T and Ac-T was observed in both the HD and LM system from 24 to 48 h, with the highest values shown in the 48 h/LM spheroids of 5000 cells (p < 0.05). In conclusion, by comparing the morphology and microtubular architecture of spheroids from C6 rat glioma cells developed by LM or HD methodology, our findings demonstrate that the use of a fumed silica microbioreactor boosts the induction and maintenance of a high plasticity state in glioma cells. RGCs cultured in LM express levels of tubulin PTMs that can be used to evaluate the efficacy of new anticancer therapies.

6.
Vet Sci ; 9(3)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35324871

RESUMO

Cystic Echinococcosis (CE) is a severe zoonosis caused by the larval stage of the tapeworm Echinococcus granulosus. These parasites are naturally transmitted between canid definitive hosts that harbour the adult stage in the intestine, and mainly ungulate intermediate hosts, with larval cysts developing in their internal organs. The close coexistence between dog and sheep with incorrect hygiene management are the most important factors for the persistence of this parasitic pathology. The Educational Farms (EF) are farms and agritourisms suitably equipped to carry out training activities for people interested in farm practices and agricultural processing, in particular student groups. Public attendance of farms represents a new potential risk factor for the zoonoses transmission. Consumption of contaminated food and water in combination with contact or playing with domestic dogs (Canis familiaris) are possible routes of zoonoses human infection. In fact, Echinococcus spp. eggs may persist in the environment up to several months at low temperatures and moist conditions, having the chance of contaminating different matrices and surfaces. The aim of this investigation was to study environmental contamination by parasitic elements as a risk for zoonoses, such as Echinococcus spp. A total of 116 samples (35 of water, 33 of soil, 23 of vegetables, 25 of dog faeces) were collected in 30 EF in Sardinia. Samples were subjected to biomolecular investigation for the research of specific gene sequences of Echinococcus granulosus, Echinococcus multilocularis and Taenia spp. The study allowed to identify eight positive EF due to the presence of Echinococcusgranulosus in eight dog faeces samples and one positive EF due to the presence of Taenia spp. in a water sample. The work has allowed to develop and harmonise the diagnostic methods and operating protocols essential for controlling the spread of the CE to create "One Health" intervention plans in high endemic areas through the implementation of SOP (standard operating procedures) for monitoring the pathology in animals, humans and environment.

7.
J Vis Exp ; (173)2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34309596

RESUMO

In livestock, in vitro embryo production systems can be developed and sustained thanks to the large number of ovaries and oocytes that can be easily obtained from a slaughterhouse. Adult ovaries always bear several antral follicles, while in pre-pubertal donors the maximal numbers of oocytes are available at 4 weeks of age, when ovaries bear peak numbers of antral follicles. Thus, 4 weeks old lambs are considered good donors, even if the developmental competence of prepubertal oocytes is lower compared to their adult counterpart. Basic research and commercial applications would be boosted by the possibility of successfully cryopreserving vitrified oocytes obtained from both adult and prepubertal donors. The vitrification of oocyte collected from prepubertal donors would also allow shortening the generation interval and thus increasing the genetic gain in breeding programs. However, the loss of developmental potential after cryopreservation makes mammalian oocytes probably one of the most difficult cell types to cryopreserve. Among the available cryopreservation techniques, vitrification is widely applied to animal and human oocytes. Despite recent advancements in the technique, exposures to high concentrations of cryoprotective agents as well as chilling injury and osmotic stress still induce several structural and molecular alterations and reduce the developmental potential of mammalian oocytes. Here, we describe a protocol for the vitrification of sheep oocytes collected from juvenile and adult donors and matured in vitro prior to cryopreservation. The protocol includes all the procedures from oocyte in vitro maturation to vitrification, warming and post-warming incubation period. Oocytes vitrified at the MII stage can indeed be fertilized following warming, but they need extra time prior to fertilization to restore damage due to cryopreservation procedures and to increase their developmental potential. Thus, post-warming culture conditions and timing are crucial steps for the restoration of oocyte developmental potential, especially when oocyte are collected from juvenile donors.


Assuntos
Ovário , Vitrificação , Animais , Criopreservação , Feminino , Fertilização in vitro , Técnicas de Maturação in Vitro de Oócitos , Oócitos , Ovinos
8.
Animals (Basel) ; 11(7)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202918

RESUMO

The reproductive seasonality of domestic animals is often manipulated in order to have more reproductive periods for commercial purposes related to the production of milk and meat. It is scientifically proven that such an alteration of the reproductive activity in sheep entails a deterioration in oocyte quality, leading to an inability to generate embryos. Since oocytes obtained from prepubertal ewes can be incorporated into an in vitro embryo production system and considering that their quality is crucial to the success of in vitro procedures, the aim of this work was to investigate the effect of seasons on the quality of prepubertal ovine oocytes collected in autumn and spring. Ovaries were collected from a local slaughterhouse from 30-40-day-old suckling lambs during both seasons. Following 24 h of in vitro maturation, oocytes developmental competence, reactive oxygen species (ROS) intracellular levels, and mitochondrial activity were evaluated, and a tubulin assessment was performed. The results on embryo production, as a percentage of first divisions and number of blastocysts obtained, were significantly higher in oocytes collected in the spring. Mitochondrial activity in oocytes was higher, and ROS production significantly lower, in spring than in autumn. Tubulin PTMs (tyrosinated and acetylated α-tubulin) showed a higher immunoreactivity in oocytes collected in spring compared with autumn sampling. Our data showed that seasons may affect the developmental competence, energetic status, and tubulin assessment of oocytes recovered from prepubertal ewes. Therefore, special care should be taken when choosing the period of the year for prepuberal ovine oocytes collection aimed at in vitro embryo reproduction programs.

9.
J Struct Biol ; 213(1): 107676, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33279655

RESUMO

Glioblastoma multiforme is the most lethal brain tumor. In the study of mechanisms underlying its development attention has been paid to the microtubular network of its cells, mainly on ßIII tubulin, considered as a marker of malignancy. In the present work, we chose to investigate the tubulin code in glioblastoma cells, analyzing the degree of interaction between tubulin post-translational modifications and different proteins associated with them. The pattern of diverse associated proteins such as EB-1, CLIP-170 and kinesin-1 and their degree of co-distribution with the most abundant post-translational tubulin modifications (tyrosination, acetylation and polyglutamylation) were evaluated. Through immunofluorescence we have shown that EB-1, CLIP-170 and kinesin-1 were well detectable in glioblastoma cells. The double fluorescence and colocalization index between the post-translational modifications of tubulin and associated proteins showed that tyrosinated α-tubulin has significantly high affinity with EB-1, CLIP-170 and kinesin-1, while for acetylated and polyglutamylated tubulin, the degree of interaction with the three associated proteins evaluated was less apparent. Data presented in this paper underline the importance of a thorough analysis of the microtubular mechanics in glioblastoma cells. This may suggest new experimental therapeutic approaches able to act more selectively on the microtubular network of cells in this type of cancer.


Assuntos
Glioma/genética , Processamento de Proteína Pós-Traducional/genética , Tubulina (Proteína)/genética , Acetilação , Animais , Linhagem Celular Tumoral , Cinesinas/genética , Microtúbulos/genética , Ratos
10.
Microorganisms ; 8(2)2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041100

RESUMO

Candida spp. are the most prevalent fungi of the human microbiota and are opportunistic pathogens that can cause oral candidiasis. Management of such infections is limited due to the low number of antifungal drugs available, their relatively high toxicity and the emergence of antifungal resistance. Therefore, much interest in the antimicrobial potential of natural compounds has recently been evident. The use of hydrogels in the delivery of biocides has been explored due to their biocompatibility, ease with drug encapsulation, and due to their potential to confer mechanical and structural properties similar to biological tissue. Methylcellulose hydrogels (10% (w/v)) with 1% (v/v) and 2% (v/v) Melissa officinalis oil were synthesised. The rheological properties and gelation time of the hydrogels were evaluated. Antimicrobial action, the antifungal potential and ability to displace Candida were determined. Rheological tests revealed that the hydrogel jellified in three minutes at 37 °C. Loaded hydrogels successfully inhibited Candida albicans growth as evident by zone of inhibition and time-kill assays. A significant reduction in retained C. albicans was demonstrated with the hydrogel at 2% Melissa officinalis concentration. This work demonstrated that an essential oil-loaded hydrogel had the potential to provide a novel antimicrobial therapy for the treatment of oral candidiasis.

11.
Theriogenology ; 148: 216-224, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31735434

RESUMO

Cryobanking of oocytes collected from prepubertal donors may supply a virtually unlimited number of female gametes for both basic research and commercial applications. Prepubertal oocytes show some structural and functional limitations compared to the adult ones that may impair their ability to recover damages from cryopreservation. In oocytes, the meiotic spindle is acutely sensitive to temperature deviation, but capable of regeneration following cryopreservation. In the present work, we studied the effects of vitrification and post-warming incubation on the microtubular cytoskeleton and the tubulin post-translational modifications (tyrosination and acetylation) in prepubertal and adult oocytes. Obtained results showed that prepubertal oocytes are more affected by vitrification-induced injuries than adult ones. In fact, prepubertal oocytes showed more severe alterations of the meiotic spindle conformation and a higher percentage of parthenogenetic activation compared to adult ones. Moreover, in the adult oocytes the equilibrium between tyrosinated and acetylated α-tubulin was restored after 4 h of post-warming incubation. Diversely, in prepubertal oocytes the imbalance between tyrosinated and acetylated α-tubulin was increased during post-warming incubation. Our study shows that prepubertal oocytes react differently to the insults provoked by vitrification compared to adult oocytes, showing an impaired ability to recover from vitrification-induced injuries. In the evaluation of oocyte ability to recover from vitrification-induced injuries, tubulin post-translational modifications represent an important indicator for assessing oocyte quality.


Assuntos
Criopreservação/veterinária , Microtúbulos/fisiologia , Oócitos/citologia , Ovinos , Envelhecimento , Animais , Tubulina (Proteína)/fisiologia , Vitrificação
12.
Theriogenology ; 110: 18-26, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29331828

RESUMO

The aim of the present study was to assess the ability of vitrified/warmed oocyte to recover from vitrification-induced damages after warming. In vitro matured, vitrified/warmed ovine oocytes were assessed for developmental competence, mitochondrial activity and distribution, ATP, ROS and catalase levels during 6 h of in vitro culture using fresh oocytes as control. ATP content in vitrified oocytes was lower than control during 4 h of post warming culture (p < .01). Vitrified oocytes were able to fill this gap only after 6 h of post-warming incubation. Moreover, mitochondrial activity was significantly lower (p < 0.01) in vitrified oocytes compared to controls, and this difference was maintained up to 2 h of incubation. Then the activity increased and at 4 h it was higher compared to controls (p < 0.01). These oocytes showed an increasing rate of clustered distribution of mitochondria which was lower than controls during the first 4 h of post warming culture (p < 0.01). ROS level was significantly higher at 0 h in vitrified compared to control oocytes and this difference was maintained also at 2 h and 6 h of incubation (p < 0.01). Catalase level was higher in vitrified oocytes than controls (p < 0.01) during the entire culture period. Cleavage and blastocyst rates were lower in vitrified oocytes compared to control ones during the two first time point of incubation period (p < .01), indeed they increased significantly from 0 to 4 h of incubation post warming (p < 0.01). The study demonstrated that vitrified/warmed oocytes need an extra time to restore damage due to cryopreservation procedures and to increase their developmental potential. Thus, time of damage recovery after vitrification could be used to standardize the vitrification protocols and to improve the developmental competence of vitrified/warmed oocytes.


Assuntos
Desenvolvimento Embrionário/fisiologia , Mitocôndrias/fisiologia , Oócitos , Oogênese/fisiologia , Ovinos/fisiologia , Vitrificação , Animais , Células Cultivadas , Criopreservação/veterinária , Técnicas de Cultura Embrionária , Feminino , Fertilização in vitro/veterinária , Temperatura Alta , Técnicas de Maturação in Vitro de Oócitos/veterinária , Masculino , Recuperação de Função Fisiológica/fisiologia
13.
Pathogens ; 7(1)2018 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-29370147

RESUMO

Management of oral candidosis, most frequently caused by Candida albicans, is limited due to the relatively low number of antifungal drugs and the emergence of antifungal tolerance. In this study, the antifungal activity of a range of commercial essential oils, two terpenes, chlorhexidine and triclosan was evaluated against C. albicans in planktonic and biofilm form. In addition, cytotoxicity of the most promising compounds was assessed using murine fibroblasts and expressed as half maximal inhibitory concentrations (IC50). Antifungal activity was determined using a broth microdilution assay. The minimum inhibitory concentration (MIC) was established against planktonic cells cultured in a range of concentrations of the test agents. The minimal biofilm eradication concentration (MBEC) was determined by measuring re-growth of cells after pre-formed biofilm was treated for 24 h with the test agents. All tested commercial essential oils demonstrated anticandidal activity (MICs from 0.06% (v/v) to 0.4% (v/v)) against planktonic cultures, with a noticeable increase in resistance exhibited by biofilms (MBECs > 1.5% (v/v)). The IC50s of the commercial essential oils were lower than the MICs, while a one hour application of chlorhexidine was not cytotoxic at concentrations lower than the MIC. In conclusion, the tested commercial essential oils exhibit potential as therapeutic agents against C. albicans, although host cell cytotoxicity is a consideration when developing these new treatments.

14.
Exp Mol Pathol ; 103(1): 26-32, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28645884

RESUMO

This study describes the effects of Lycium barbarum polysaccharides (LBP) on testicular damage induced by cadmium (Cd). Adult male rats were i.p. injected with CdCl2 (4mg/Kg, once) with or without LBP pretreatment (300mg/Kg orally, once a day, for 30days). Testis weight, morphological/histological structure and oxidative stress parameters were evaluated. Several adverse effects were observed after CdCl2 injection, with a significant decrease in body/testis weight ratio (P<0.05), gross morphological changes with hyperemia of the parenchyma, increased volume and alteration in the structure of the seminiferous tubules. Furthermore, Cd intoxication caused a significant decrease of glutathione (GSH) and Trolox equivalent antioxidant capacity (TEAC) in testis (P<0.05) together with a significant increase (P<0.01) of 3-nitro-l-tyrosine (3NT) while malondialdehyde (MDA) did not change. LBP pretreatment caused slight signs of improvement in the morphology of the seminiferous tubules. Our results confirm that Cd induces testicular damage and suggest the oxidative stress involvement. LBP could ameliorate Cd testicular damage but further investigations are needed.


Assuntos
Cádmio/toxicidade , Medicamentos de Ervas Chinesas/farmacologia , Testículo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Glutationa/metabolismo , Masculino , Malondialdeído/metabolismo , Tamanho do Órgão , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Testículo/patologia , Tirosina/análogos & derivados , Tirosina/metabolismo
15.
Biotechnol Bioeng ; 114(9): 1978-1990, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28409838

RESUMO

Mammalian cell perfusion cultures are gaining renewed interest as an alternative to traditional fed-batch processes for the production of therapeutic proteins, such as monoclonal antibodies (mAb). The steady state operation at high viable cell density allows the continuous delivery of antibody product with increased space-time yield and reduced in-process variability of critical product quality attributes (CQA). In particular, the production of a confined mAb N-linked glycosylation pattern has the potential to increase therapeutic efficacy and bioactivity. In this study, we show that accurate control of flow rates, media composition and cell density of a Chinese hamster ovary (CHO) cell perfusion bioreactor allowed the production of a constant glycosylation profile for over 20 days. Steady state was reached after an initial transition phase of 6 days required for the stabilization of extra- and intracellular processes. The possibility to modulate the glycosylation profile was further investigated in a Design of Experiment (DoE), at different viable cell density and media supplement concentrations. This strategy was implemented in a sequential screening approach, where various steady states were achieved sequentially during one culture. It was found that, whereas high ammonia levels reached at high viable cell densities (VCD) values inhibited the processing to complex glycan structures, the supplementation of either galactose, or manganese as well as their synergy significantly increased the proportion of complex forms. The obtained experimental data set was used to compare the reliability of a statistical response surface model (RSM) to a mechanistic model of N-linked glycosylation. The latter outperformed the response surface predictions with respect to its capability and reliability in predicting the system behavior (i.e., glycosylation pattern) outside the experimental space covered by the DoE design used for the model parameter estimation. Therefore, we can conclude that the modulation of glycosylation in a sequential steady state approach in combination with mechanistic model represents an efficient and rational strategy to develop continuous processes with desired N-linked glycosylation patterns. Biotechnol. Bioeng. 2017;114: 1978-1990. © 2017 Wiley Periodicals, Inc.


Assuntos
Anticorpos Monoclonais/metabolismo , Reatores Biológicos , Modelos Biológicos , Perfusão/instrumentação , Perfusão/métodos , Polissacarídeos/metabolismo , Animais , Anticorpos Monoclonais/isolamento & purificação , Células CHO , Simulação por Computador , Desenho Assistido por Computador , Cricetulus , Desenho de Equipamento , Análise de Falha de Equipamento , Glicosilação
16.
Biotechnol Prog ; 33(4): 879-890, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27997765

RESUMO

Perfusion cell culture processes allow the steady-state culture of mammalian cells at high viable cell density, which is beneficial for overall product yields and homogeneity of product quality in the manufacturing of therapeutic proteins. In this study, the extent of metabolic steady state and the change of the metabolite profile between different steady states of an industrial Chinese hamster ovary (CHO) cell line producing a monoclonal antibody (mAb) was investigated in stirred tank perfusion bioreactors. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) of daily cell extracts revealed more than a hundred peaks, among which 76 metabolites were identified by tandem MS (MS/MS) and high resolution Fourier transform ion cyclotron resonance (FT-ICR) MS. Nucleotide ratios (Uridine (U)-ratio, nucleotide triphosphate (NTP)-ratio and energy charge (EC)) and multivariate analysis of all features indicated a consistent metabolite profile for a stable culture performed at 40 × 106 cells/mL over 26 days of culture. Conversely, the reactor was operated continuously so as to reach three distinct steady states one after the other at 20, 60, and 40 × 106 cells/mL. In each case, a stable metabolite profile was achieved after an initial transient phase of approximately three days at constant cell density when varying between these set points. Clear clustering according to cell density was observed by principal component analysis, indicating steady-state dependent metabolite profiles. In particular, varying levels of nucleotides, nucleotide sugar, and lipid precursors explained most of the variance between the different cell density set points. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:879-890, 2017.


Assuntos
Anticorpos Monoclonais/biossíntese , Reatores Biológicos , Técnicas de Cultura de Células , Metaboloma , Perfusão , Animais , Células CHO , Células Cultivadas , Cricetulus , Análise Multivariada , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Massas em Tandem
17.
Environ Sci Pollut Res Int ; 24(3): 2946-2955, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27844321

RESUMO

The aim of this study was to investigate the potential protective effect of Lycium barbarum polysaccharides (LBP) pretreatment against cadmium (Cd)-induced hepatotoxicity in rats. Wistar rats were divided into control group, LBP group (300 mg/kg orally, once a day, for 30 days), Cd group (CdCl2 4 mg/kg i.p. once), and LBP + Cd group (LBP 300 mg/kg orally, once a day, for 30 days + CdCl2 4 mg/kg i.p. 24 h after the last treatment). Cd liver injury was examined by morphological/histological changes, transaminases, total protein concentration, and oxidative stress evaluated by MDA, 3NT, GSH, SOD, and TEAC activities. Cd intoxication caused gross morphological changes with hyperemia of the parenchyma, increased volume, and disappearance of the anatomical limits of the lobes associated with an increase of ALT, GSH, and TEAC in plasma and a decrease of MDA, GSH, and TEAC in liver, SOD, and total proteins in plasma. LBP pretreatment caused a slight improvement in the histological architecture and in the 3NT amount together with a significant improvement of hematic parameters. On the basis of the obtained results, we can affirm that LBP pretreatment can ameliorate liver conditions, but further studies are needed to better evaluate the protective antioxidant effects of LBP against Cd-induced toxicity.


Assuntos
Antioxidantes/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Estresse Oxidativo , Animais , Cádmio , Fígado/metabolismo , Lycium , Masculino , Polissacarídeos/metabolismo , Ratos , Ratos Wistar
18.
Int J Biol Sci ; 1(1): 19-23, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15951846

RESUMO

The Hox gene cluster has been a key paradigm for a generation of developmental and evolutionary biologists. Since its discovery in the mid-1980's, the identification, genomic organization, expression, colinearity, and regulation of Hox genes have been immediate targets for study in any new model organism, and metazoan genome projects always refer to the structure of the particular Hox cluster(s). Since the early 1990's, it has been dogma that vertebrate Hox clusters are composed of thirteen paralogous groups. Nonetheless, we showed that in the otherwise prototypical cephalochordate amphioxus (Branchiostoma floridae), the Hox cluster contains a fourteenth Hox gene, and very recently, a 14(th) Hox paralogous group has been found in the coelacanth and the horn shark, suggesting that the amphioxus cluster was anticipating the finding of Hox 14 in some vertebrate lineages. In view of the pivotal place that amphioxus occupies in vertebrate evolution, we thought it of considerable interest to establish the limits of its Hox gene cluster, namely resolution of whether more Hox genes are present in the amphioxus cluster (e.g., Hox 15). Using two strategies, here we report the completion and characterization of the Hox gene content of the single amphioxus Hox cluster, which encompasses 650 kb from Hox1 to Evx. Our data have important implications for the primordial Hox gene cluster of chordates: the prototypical nature of the single amphioxus Hox cluster makes it unlikely that additional paralogous groups will be found in any chordate lineage. We suggest that 14 is the end.


Assuntos
Cordados não Vertebrados/genética , Genes Homeobox/genética , Família Multigênica/genética , Animais , Passeio de Cromossomo , Cosmídeos/genética , Evolução Molecular , Duplicação Gênica , Biblioteca Gênica , Hibridização in Situ Fluorescente
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