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1.
Genet Mol Res ; 16(1)2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-28218785

RESUMO

Recent innovations in the genomic understanding of medulloblastomas have provided new ways to explore this highly invasive malignant brain cancer arising from the cerebellum. Among the four different medulloblastoma subgroups described to date, the sonic hedgehog (SHH) genetic pathway is the pathway activated in the tumorigenesis of medulloblastoma. SHH-related medulloblastomas are usually of nodular/desmoplastic histology and frequently occur in children under the age of three, an age group highly susceptible to the acute and long-term effects of treatment. Several new drugs aimed at SHH modulation are currently under development. This review focuses on the role of arsenic trioxide, a drug well established in clinical practice and probably an under-explored agent in medulloblastoma management, in the SHH pathway.


Assuntos
Antineoplásicos/administração & dosagem , Arsenicais/administração & dosagem , Neoplasias Cerebelares/tratamento farmacológico , Proteínas Hedgehog/metabolismo , Meduloblastoma/tratamento farmacológico , Óxidos/administração & dosagem , Adolescente , Antineoplásicos/farmacologia , Trióxido de Arsênio , Arsenicais/farmacologia , Neoplasias Cerebelares/metabolismo , Criança , Pré-Escolar , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lactente , Meduloblastoma/metabolismo , Óxidos/farmacologia , Transdução de Sinais/efeitos dos fármacos
2.
Clin Exp Immunol ; 183(3): 480-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26472479

RESUMO

T helper type 17 (Th17) cytokines have been implicated in the pathogenesis of neuromyelitis optica (NMO). As humanized anti-interleukin (IL)-6R (tocilizumab) immunoglobulin (Ig)G has been used as disease-modifying therapy for NMO, the objective of our study was to investigate the role of endogenous IL-6 on NMO-derived CD4(+) T cell behaviour. High production of IL-6, IL-17 and IL-21 by CD4(+) T-cells was detected in NMO patients. Further, IL-21 and IL-6 levels were related directly to the level of neurological disabilities. The addition of anti-IL-6R IgG not only reduced directly the production of these cytokines, but also almost abolished the ability of activated autologous monocytes in enhancing IL-6, IL-17 and IL-21 release by CD4(+) T cells. In contrast, the production of IL-10 was amplified in those cell cultures. Further, anti-IL-6R monoclonal antibodies (mAb) also potentiated the ability of glucocorticoid in reducing Th17 cytokines. Finally, the in-vivo and in-vitro IL-6 levels were significantly higher among those patients who experienced clinical relapse during 2-year follow-up. In summary, our results suggest a deleterious role of IL-6 in NMO by favouring, at least in part, the expansion of corticoid-resistant Th17 cells.


Assuntos
Interleucina-6/fisiologia , Neuromielite Óptica/tratamento farmacológico , Neuromielite Óptica/imunologia , Adulto , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Linfócitos T CD4-Positivos , Resistência a Medicamentos , Feminino , Seguimentos , Humanos , Hidrocortisona/farmacologia , Interleucina-10/sangue , Interleucina-17/sangue , Interleucinas/biossíntese , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Receptores de Interleucina-6/metabolismo , Indução de Remissão , Índice de Gravidade de Doença , Células Th17/efeitos dos fármacos , Células Th17/imunologia
3.
Andrologia ; 47(1): 85-90, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24428535

RESUMO

This study evaluated the effects of dietary organic selenium (Se) on viability of chilled boar semen. Twelve boars were divided into three groups: control (CON), 0.3 mg kg(-1) sodium selenite; inorganic (INO), 0.5 mg kg(-1) sodium selenite and organic (ORG), 0.5 mg kg(-1) Se yeast. The experiment was conducted within 10 weeks, and analysis was performed fortnightly, in storage semen by 72 h. No effect was observed on motility; however, straightness and linearity percentages were higher (P < 0.05) in the animals receiving CON diet compared with INO group. Percentages of cells with both plasma and acrosomal intact membranes, lipidic membrane peroxidation and mitochondrial membrane potential were similar on all treatments. Animals receiving CON diet presented higher (P < 0.05) values of ATP when compared with INO group. The PHGPx was higher (P < 0.05) in animals that received ORG in comparison with INO group. In conclusion, organic selenium supplementation increases PHGPx but does not improve chilled semen viability in 72 h.


Assuntos
Antioxidantes/farmacologia , Suplementos Nutricionais , Glutationa Peroxidase/efeitos dos fármacos , Selênio/farmacologia , Espermatozoides/efeitos dos fármacos , Acrossomo/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Masculino , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Análise do Sêmen , Preservação do Sêmen , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/enzimologia , Suínos
4.
Reprod Domest Anim ; 49(6): 964-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25251704

RESUMO

The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty-nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post-weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning-to-oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation.


Assuntos
Gonadotropina Coriônica/farmacologia , Hormônio Luteinizante/farmacologia , Paridade/fisiologia , Maturidade Sexual/efeitos dos fármacos , Suínos/fisiologia , Animais , Ciclo Estral , Feminino , Inseminação Artificial/veterinária , Gravidez
5.
Brain Impair ; 24(3): 721-731, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38167367

RESUMO

OBJECTIVE: Decompressive craniectomy is part of the acute management of several neurosurgical illnesses, and is commonly followed by cranioplasty. Data are still scarce on the functional and cognitive outcomes following cranioplasty. We aim to evaluate these outcomes in patients who underwent cranioplasty following traumatic brain injury (TBI) or stroke. METHODS: In this prospective cohort, we assessed 1-month and 6-month neuropsychological and functional outcomes in TBI and stroke patients who underwent cranioplasty at a Brazilian tertiary center. The primary outcome was the change in the Digits Test at 1 and 6 months after cranioplasty. Repeated measures general linear models were employed to assess the patients' evolution and interactions with baseline characteristics. Effect size was estimated by the partial η2. RESULTS: A total of 20 TBI and 14 stroke patients were included (mean age 42 ± 14 years; 52.9% male; average schooling 9.5 ± 3.8 years; 91.2% right-handed). We found significant improvements in the Digits Tests up to 6 months after cranioplasty (p = 0.004, partial η2 = 0.183), as well as in attention, episodic memory, verbal fluency, working memory, inhibitory control, visuoconstructive and visuospatial abilities (partial η2 0.106-0.305). We found no interaction between the cranioplasty effect and age, sex or schooling. Patients submitted to cranioplasty earlier (<1 year) after injury had better outcomes. CONCLUSION: Cognitive and functional outcomes improved after cranioplasty following decompressive craniectomy for stroke or TBI. This effect was consistent regardless of age, sex, or education level and persisted after 6 months. Some degree of spontaneous improvement might have contributed to the results.


Assuntos
Lesões Encefálicas Traumáticas , Craniectomia Descompressiva , Acidente Vascular Cerebral , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Lactente , Feminino , Estudos de Coortes , Estudos Prospectivos , Resultado do Tratamento , Craniectomia Descompressiva/efeitos adversos , Lesões Encefálicas Traumáticas/cirurgia , Acidente Vascular Cerebral/cirurgia
6.
Andrologia ; 44 Suppl 1: 154-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22506813

RESUMO

The success of semen cryopreservation is influenced by several factors, such as freezing curves and cryoprotectants. These two factors are of special interest once they may lead to many important physical-chemical changes resulting in different degrees of damage in spermatozoa structure. This experiment was designed to compare the effect of bull semen cryopreservation using two freezing techniques: conventional (CT--cooling rate of -0.55 °C min(-1) and freezing rate of -19.1 °C min(-1) and automated (AT--cooling rate of -0.23 °C min(-1) and freezing rate of -15 °C min(-1)), performed with different curves, and with three cryoprotectants (glycerol, ethylene glycol and dimethyl formamide) on bovine sperm motility and integrity of plasma, acrosomal and mitochondrial membranes. These variables were simultaneously evaluated using the fluorescence probes propidium iodide, fluorescein-conjugated Pisum sativum agglutinin and MitoTracker Green FM. The effects of freezing techniques, as well as of different cryoprotectants were analysed by the analysis of variance. The means were compared by Fisher's test. There were no significant differences between freezing techniques (P > 0.05). Glycerol showed higher percentages of motility, vigour and integrity of plasma, acrosomal and mitochondrial membranes than other two cryoprotectants (P < 0.05). Ethylene glycol preserved higher motility and integrity of plasma and mitochondrial membranes than dimethyl formamide (P < 0.05). Sperm motility with glycerol was 30.67 ± 1.41% and 30.50 ± 1.06%, with ethylene glycol was 21.17 ± 1.66% and 21.67 ± 1.13% and with dimethyl formamide was 8.33 ± 0.65% and 9.17 ± 0.72% to CT and AT curves, respectively. The percentage of spermatozoa with simultaneously intact plasma membrane, intact acrosome and mitochondrial function (IPIAH) was 14.82 ± 1.49% (CT) and 15.83 ± 1.26% (AT) to glycerol, 9.20 ± 1.31% (CT) and 9.92 ± 1.29% (AT) to ethylene glycol 4.65 ± 0.93% (CT) and 5.17 ± 0.87% (AT) to dimethyl formamide. Glycerol provided the best results, although nearly 85% of spermatozoa showed some degree of injury in their membranes, suggesting that further studies are required to improve the results of cryopreservation of bovine semen.


Assuntos
Acrossomo , Criopreservação , Congelamento , Membranas Intracelulares/metabolismo , Mitocôndrias , Preservação do Sêmen , Animais , Bovinos , Masculino
7.
Andrologia ; 44(1): 9-15, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21615453

RESUMO

The objective of this study was to evaluate the quality of bovine frozen-thawed sperm cells after Percoll gradient centrifugation. Frozen semen doses were obtained from six bulls of different breeds, including three taurine and three Zebu animals. Four ejaculates per bull were evaluated before and after discontinuous Percoll gradient centrifugation. Sperm motility was assessed by computer-assisted semen analysis and the integrity of the plasma and acrosomal membranes, as well as mitochondrial function, were evaluated using a combination of fluorescent probes propidium iodide, fluorescein isothiocyanate-conjugated Pisum sativum agglutinin and 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide. The procedure of Percoll gradient centrifugation increased the percentage of total and progressive sperm motility, beat frequency, rectilinear motility, linearity and rapidly moving cells. In addition, the percentage of cells with intact plasma membrane and mitochondrial membrane potential was increased in post-centrifugation samples. However, the percentage of sperm cells with intact acrosomal membrane was markedly reduced. The method used selected the motile cells with intact plasma membrane and higher mitochondrial functionality in frozen-thawed bull semen, but processing, centrifugation and/or the Percoll medium caused damage to the acrosomal membrane.


Assuntos
Análise do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Bovinos , Separação Celular/veterinária , Centrifugação com Gradiente de Concentração , Computadores , Criopreservação/veterinária , Corantes Fluorescentes , Masculino , Povidona , Preservação do Sêmen/veterinária , Dióxido de Silício , Motilidade dos Espermatozoides
8.
Anim Reprod Sci ; 246: 106946, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35216848

RESUMO

When preserving sperm in the liquid or cryopreserved state, seminal plasma (SP) components within ejaculates can alter fertilizing capacity of these gametes. Depending on the species or how semen is collected, volume and concentration of SP components varies considerably. The SP contains substances essential for maintenance of sperm viability and fertility; however, these components can be deleterious depending on quantity, or duration of time before there is removal of SP from sperm in semen processing. Substances that impair (e.g., BSP - bull; HSP-1 - stallion; Major seminal plasma protein PSPI - boar) or improve (e.g., spermadhesin PSP-I - boar) spermatozoa fertilizing capacity have been identified. Depending on individual males, species, and semen collection procedures, SP removal may be beneficial before preservation in the liquid or cryopreserved state. In some cases, SP that is removed can be added back to thawing extender with there being positive effects in thawed sperm and for sperm viability in the female reproductive tract. In this review article, there is a focus on different effects of SP in samples of cooled and cryopreserved semen from four domestic species (pigs, horses, cattle, and sheep) with there being emphasis on how SP modulates the function and morphology of sperm cells before, during, and after preservation in the refrigerated or cryopreserved state. The present review is part of the Festschrift in honor of Dr. Duane Garner who made major contributions to the area of focus in this manuscript as evidenced by the many times his research is cited in this manuscript.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Animais , Suínos , Cavalos , Bovinos , Feminino , Ovinos , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides , Criopreservação/veterinária , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides
9.
Reprod Domest Anim ; 46(4): 682-6, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21121969

RESUMO

Effect of seminal plasma addition after thawing on viability or cryocapacitation is not definitively established. This experiment was performed to verify the effect of adding seminal plasma, autologous or homologous (from an animal with good semen freezability). Five ejaculates from each of four stallions with proven fertility were collected and cryopreserved. The semen was subsequently thawed and divided into the following three treatment groups: no seminal plasma addition after semen thawing (NOSP); the addition of homologous seminal plasma after semen thawing (HSP) and the addition of autologous seminal plasma after semen thawing (ASP). The addition of 20% of seminal plasma led to an increase in the cell population that simultaneously show plasma and acrosomal membrane integrity (p < 0.05). The addition of seminal plasma did not alter the total motility, the amount of cells with mitochondrial membrane potential or the sperm velocities (average path velocity, straight-line velocity and curvilinear velocity). However, the beat/cross-frequency, straightness and linearity were reduced in ASP and HSP groups (p < 0.05). Unexpectedly, the addition of homologous seminal plasma reduced the proportion of cells with progressive motility (p < 0.05) and the addition of autologous seminal plasma reduced the amplitude of the lateral head displacement (p < 0.05). Based on the increase in the cell populations that had the plasma and acrosomal membrane integrity simultaneously identified in this study, we proposed that the addition of seminal plasma (autologous or homologous) into post-thawed semen before insemination could increase semen fertility.


Assuntos
Criopreservação/veterinária , Cavalos/fisiologia , Sêmen/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Animais , Inseminação Artificial/veterinária , Masculino , Preservação do Sêmen/veterinária
10.
J Exp Med ; 152(5): 1375-92, 1980 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-7000967

RESUMO

Trypanosoma cruzi at various stages of maturation and differentiation have been isolated by conventional cellular fractionation procedures and characterized by cell surface markers using 30 highly purified lectins encompassing all known sugar specificities. Cell surface carbohydrates of the various T. cruzi stages were analyzed by agglutination and lectin-binding assays. Specific receptors for wheat germ agglutinin (WGA), Helix pomatia, Sophora japonica, and Bandeiraea simplicifolia lectin II were found only in culture epimastigotes, whereas peanut agglutinin (PNA) sites were present exclusively in amastigotes, those for Phaseolus vulgaris in bloodstream trypomastigotes and amastigotes, and for Wistaria floribunda hemagglutinin predominantly in culture forms of T. cruzi. The N-acetylgalactosamine (DGalNAc)-binding lectin from Bauhinia purpurea agglutinated and inhibited the movement of epimastigotes and bloodstream trypomastigotes, but it only inhibited--without agglutinating--culture trypomastigotes. Because both the agglutination and inhibition of movement were reversed by specific sugar haptens, Bauhinia purpurea sites were present in all the flagellated parasites. On the other hand, PNA sites were detectable on epimastigotes after the cells were treated with sialidase, whereas, at the same time, WGA receptors were completely removed and those for the other sialic acid-binding proteins, Aaptos papillata lectin II and Limulus polyphemus, were partially eliminated; moreover, the activity of Wistaria floribunda hemagglutinin, a DGalNAc-binding lectin, increased 4,000 times. Trypsinization and lyzozyme treatment of epimastigote cells did not significantly affect lectin agglutination or lectin binding. WGA reacted solely with sialic acid residues on epimastigote cell surface with an apparent association constant of 2 x 10(6) M-1, each epimastigote having an estimated average of 3 x 10(6) WGA sites, as determined by binding experiments and a minimum of 7.7 x 10(6) sialic acid residues, as calculated by colorimetric method after sialidase digestion. Evidences are presented that the sialyl residues are rapidly regenerated (in approximately 4 h) and that they, at least for the most part, are not adsorbed from the culture medium. The receptor for the D-mannose-binding lectins (concanavalin A [Con A] and Lens culinaris) must either be on the same carbohydrate moiety having the WGA site, or, if in a distinct molecule, both carrier molecules of Con A and WGA sites must be located close to each other in the plasma membrane of the parasite.


Assuntos
Lectinas/metabolismo , Receptores Mitogênicos/metabolismo , Ácidos Siálicos/metabolismo , Trypanosoma cruzi/metabolismo , Animais , Antígenos de Superfície/imunologia , Sítios de Ligação , Larva , Camundongos
11.
Animal ; 14(9): 1899-1905, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32290879

RESUMO

The use of altrenogest (ALT) supplementation for oestrous synchronization improves subsequent reproductive performance of gilts and sows. However, the causes of this improvement in reproductive performance after ALT treatment are not fully/clearly understood. The objective of this study was to evaluate the effects of ALT supplementation for oestrous synchronization in gilts on the endometrial glands and embryonic development characteristics at 28 days of pregnancy. Pregnant gilts were divided into two experimental treatments: Control (did not receive ALT; n = 9 gilts) and ALT (ALT feeding at 20 mg/day for 18 days; n = 9 gilts). At 28 days of pregnancy, six gilts from each treatment were slaughtered, and reproductive tracts were immediately evaluated. There was no statistical difference (P > 0.05) between treatments regarding ovulation rate, number of embryos, number of vital embryos and number of non-vital embryos. Embryo weight, length and embryonic vesicle weight were lower in ALT treatment compared with Control (P < 0.01), and it was lower in the cervical uterine region compared with apex uterine region, respectively (P < 0.05). Higher values of gland duct area, gland duct perimeter, percentage of the glandular area and total endometrial area were observed in ALT treatment compared with Control (P < 0.05). The use of ALT during 18 days for oestrous synchronization in gilts increased the gland duct area, perimeter and total endometrial area but did not increase the embryo number and embryo size at day 28 of pregnancy.


Assuntos
Estro , Acetato de Trembolona , Animais , Endométrio , Feminino , Ovulação , Gravidez , Suínos , Acetato de Trembolona/análogos & derivados , Acetato de Trembolona/farmacologia
12.
Animal ; 14(1): 50-58, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31280736

RESUMO

The use of additives such as ractopamine (Rac) in pregnant sows during early-mid pregnancy is an alternative to increase foetal and progeny growth and development. However, Rac supplementation in finishing pigs can lead to behavioural and physiological changes similar to the typical stress responses. The objective of this study was to evaluate the effects of dietary supplementation with Rac in pregnant sows from day 25 to 50 of gestation (pre-hyperplastic stage) on piglet's vitality, blood parameters, number, diameter and perimeter of muscle fibres in semitendinosus muscle and developmental characteristics of piglets at birth to weaning. Forty-one hybrid sows were divided into three dietary treatments: (1) control diet without Rac (control), (2) addition of 10 mg/kg of Rac (Rac10) and (3) addition of 20 mg/kg of Rac (Rac20). Higher numbers of low-vitality piglets (P<0.05) were observed in Rac-fed sows, regardless of dose, compared with the control group. Very low-density lipoprotein levels were lower in the Rac10 group when compared with the Rac20 group at day 21. Haematocrit was greater, and the mean corpuscular haemoglobin concentration was lower in piglets from Rac-fed sows. No significant statistical differences were detected regarding piglets body weight, average daily gain, blood gasometry, complete blood count and muscle fibre measurements in semitendinosus muscle. The use of Rac in pregnant sows reduced the vitality parameters of piglets but did not improve the performance from birth until weaning and did not negatively influence the haematological parameter and lipid metabolism.


Assuntos
Fenetilaminas/metabolismo , Sus scrofa/fisiologia , Ração Animal/análise , Animais , Animais Recém-Nascidos/sangue , Animais Recém-Nascidos/fisiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Fenetilaminas/administração & dosagem , Gravidez , Sus scrofa/sangue
13.
Animal ; 14(6): 1234-1240, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31907084

RESUMO

Progesterone (P4) plays a key role in pregnancy establishment and maintenance; during early pregnancy, P4 stimulates the production and release of uterine secretions necessary for conceptus growth prior to implantation; therefore, exogenous P4 supplementation may improve embryo development. This study evaluated the effects of supplementation during early pregnancy with long-acting injectable progesterone or altrenogest on embryonic characteristics of sows and gilts. Thus, a total of 32 sows and 16 gilts were used. On day 6 of pregnancy sows and gilts were allocated to one of the following groups: non-supplemented; supplemented with 20 mg of altrenogest, orally, from days 6 to 12 of pregnancy; supplemented with 2.15 mg/kg of long-acting injectable progesterone on day 6 of pregnancy. Animals were killed on day 28 of pregnancy, and ovulation rate, embryo survival, embryo weight, crown-to-rump length, uterine glandular epithelium and endometrial vascularization were assessed. Treatments had no effect on pregnancy rate, embryo survival or endometrial vascular density (P > 0.05). Non-supplemented gilts presented larger and heavier embryos compared to gilts from supplemented groups (P < 0.05). Sows in the altrenogest group presented larger and heavier embryos compared to non-supplemented sows and sows supplemented with long-acting injectable progesterone. In conclusion, supplementation of sows and gilts with progestagen from day 6 of pregnancy can be used as a means to improve embryo survival without deleterious effects.


Assuntos
Implantação do Embrião/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Prenhez , Suínos/fisiologia , Acetato de Trembolona/análogos & derivados , Animais , Suplementos Nutricionais , Embrião de Mamíferos , Endométrio , Feminino , Ovulação/fisiologia , Gravidez , Taxa de Gravidez , Prenhez/efeitos dos fármacos , Progestinas/administração & dosagem , Progestinas/farmacologia , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/farmacologia
14.
Science ; 211(4482): 597-600, 1981 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-7006082

RESUMO

Lectins of different activities were found in the crop, midgut, and hemolymph of the insect Rhodnius prolixus. These were not specific for N-acetyl-D-mannosamine, alpha-N-acetyl-D-galactosamine, and alpha- and beta-galactose, respectively. Lectin receptors were detectable in epimastigote but not in trypomastigote forms of Trypanosoma cruzi, a protozoan parasite of the insect and of humans.


Assuntos
Insetos Vetores/parasitologia , Lectinas , Rhodnius/parasitologia , Triatominae/parasitologia , Trypanosoma cruzi/fisiologia , Animais , Hemaglutininas , Hemolinfa/parasitologia , Rhodnius/anatomia & histologia , Trypanosoma cruzi/crescimento & desenvolvimento
15.
Theriogenology ; 124: 32-38, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30336301

RESUMO

Ivermectin (IVM) is a macrocyclic lactone used as a broad spectrum antiparasitic agent against nematodes and arthropods. It is mainly used in the control of parasitic infections of domestic animals, and recently has been used in humans to treat onchocerciasis, scabies, and pediculosis. In mammals, evidence has indicated that macrocyclic lactones interact with gamma-aminobutyric acid (GABA)-mediated chloride channels. The GABAergic system is known to be involved in the manifestation of sexual behavior, and previous studies have shown that IVM impaired sexual behavior in both male and female rats. Thus, considering that IVM may interfere with the sexual sphere, this study evaluated the temporal (1 up 60 days) effects of exposure to IVM (0.2 and 1.0 mg/kg, administered subcutaneously) on seminal and hormonal parameters of male rabbits. In male rabbits, the spermatozoa concentration, motility and morphology, the integrity of the plasmatic, acrosomal and mitochondrial membranes of the spermatozoa, the organ weights, gonadosomatic index, serum testosterone concentrations, histopathological findings were evaluated and hematological and serum biochemical analysis was conducted. No changes were observed in male seminal parameters evaluated by spermatozoa concentration, motility, and morphology, nor the potential for fertilization evaluated by the integrity of the plasmatic, acrosomal, and mitochondrial membranes of the spermatozoa; there was also no interference in serum testosterone concentration, serum biochemistry and hematological parameters. The findings of this study using the artificial vagina for collection of semen and computer-assisted semen analysis showed that IVM at doses of 0.2 and 1.0 mg/kg of SC did not alter any of the semen parameters of rabbits evaluated for up to 60 days after administration.


Assuntos
Antiparasitários/efeitos adversos , Ivermectina/efeitos adversos , Coelhos , Sêmen/efeitos dos fármacos , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/patologia , Animais , Genitália Masculina/efeitos dos fármacos , Genitália Masculina/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Tamanho do Órgão , Contagem de Espermatozoides/veterinária , Espermatozoides/efeitos dos fármacos , Testosterona/sangue
16.
Arch Microbiol ; 190(5): 521-30, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18575847

RESUMO

The genus Corynebacterium is part of the phylogenetic group nocardioform actinomycetes. Members of this group have a characteristic cell envelope structure composed primarily of branched long-chain lipids, termed mycolic acids, and a rich number of lipoglycans such as lipoarabinomanans (LAM) and lipomannans. In this study, we identified a novel LAM variant isolated from Corynebacterium diphtheriae named CdiLAM. The key structural features of CdiLAM are a linear alpha-1-->6-mannan with side chains containing 2-linked alpha-D-Manp and 4-linked alpha-D-Araf residues. The polysaccharide backbone is linked to a phosphatidylinositol anchor. In contrast to the LAMs of other members of actinomycetales, CdiLAM presents an unusual substitution at position 4 of alpha-1-->6-mannan backbone by alpha-D-Araf. Unlike the non-fimbrial adhesin 62-72p, CdiLAM did not function as a hemagglutinin to human red blood cells. Experimental evidences pointed to CdiLAM as an adhesin of C. diphtheriae to human respiratory epithelial cells, thereby, contributing to the pathogenesis of diphtheria.


Assuntos
Adesinas Bacterianas/metabolismo , Aderência Bacteriana , Corynebacterium diphtheriae/química , Corynebacterium diphtheriae/fisiologia , Células Epiteliais/microbiologia , Lipopolissacarídeos/metabolismo , Adesinas Bacterianas/química , Sequência de Carboidratos , Eritrócitos/microbiologia , Hemaglutinação , Humanos , Lipopolissacarídeos/química , Dados de Sequência Molecular , Estrutura Molecular , Fosfatidilinositóis/química
17.
Anim Reprod Sci ; 198: 20-26, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30219377

RESUMO

Seminal plasma (SP), the fluid that surrounds the sperm cells, is known to exert substantial influence on sperm physiology. The SP has a pivotal role in sperm function in vivo, and due to its components, it functions in an ambiguous manner in vitro, simultaneously possessing deleterious and beneficial effects. This experiment aimed to describe the differences between the presence or absence of SP from the sperm-rich fraction on some spermatozoa characteristics (kinetics, plasma and acrosome membrane integrity, lipid peroxidation and capacitation-like changes). Furthermore, this experiment focused on distinguishing the effects of SP on the variables evaluated from the effects of centrifugation during SP removal. Total and progressive sperm motility, as well as integrity of plasma and acrosome membranes, were less (P < 0.05) in the absence of SP. Membrane lipid peroxidation (P < 0.05) and sperm membrane stability (P < 0.05) did not differ among treatments. The SP from the sperm-rich fraction is important for the maintenance of adequate structural and functional characteristics of extended liquid boar semen and should be present in seminal doses throughout storage. Furthermore, the detrimental effect on the variables evaluated was caused solely by the absence of SP and not by the process of removal through centrifugation at 500 x g for 10 min.


Assuntos
Criopreservação , Análise do Sêmen , Preservação do Sêmen , Sêmen/fisiologia , Espermatozoides/citologia , Animais , Centrifugação , Criopreservação/métodos , Criopreservação/veterinária , Masculino , Sêmen/citologia , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Contagem de Espermatozoides , Motilidade dos Espermatozoides/fisiologia , Suínos
18.
J Anim Sci ; 94(5): 1906-12, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27285688

RESUMO

Boar spermatozoa arising from the sperm-rich ejaculate fraction are reported to have a more stable plasma membrane and are more resistant to cold shock and premature acrosome reaction than spermatozoa from the whole ejaculate. Furthermore, seminal plasma (SP) can increase the cryotolerance of boar spermatozoa, and in other domestic species, it has the ability to reverse cryopreservation damage. This study aimed to evaluate the effects of boar SP arising from the whole sperm-rich ejaculate fraction (SP-SRF) on the integrity, stability, and peroxidation of sperm membranes after thawing. Each ejaculate ( = 24) was divided among 4 treatments: control (CT), centrifuged and suspended in autologous SP-SRF (CS), centrifuged with withdrawn SP-SRF (CW), and post-thawed SP arising from the whole sperm-rich fraction addition to CW (CWSP). After thawing, all treatments were incubated for 5, 60, and 120 min and were analyzed for membrane integrity, fluidity, and peroxidation by flow cytometer. The absence of SP-SRF increased the lipid disorder ( < 0.05) but had no effect on lipid peroxidation ( > 0.05) or membrane integrity ( > 0.05). However, the increase in lipid disorder by withdrawal of SP-SRF was reversed by SP-SRF addition ( < 0.05) to the post-thawing medium, whereas plasma and acrosomal membrane integrity ( > 0.05) and lipid peroxidation ( > 0.05) were unchanged. In conclusion, despite the centrifugation effects, the addition of SP arising from the whole sperm-rich fraction to post-thawed boar semen decreased sperm lipid disorder without an influence of the sperm membrane integrity and peroxidation.


Assuntos
Membrana Celular/fisiologia , Criopreservação/veterinária , Preservação do Sêmen/veterinária , Sêmen/fisiologia , Espermatozoides/fisiologia , Suínos , Reação Acrossômica , Animais , Citometria de Fluxo , Peroxidação de Lipídeos , Masculino , Análise do Sêmen , Motilidade dos Espermatozoides , Espermatozoides/citologia
19.
Environ Sci Pollut Res Int ; 22(19): 14781-92, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25989858

RESUMO

The goal of the present research work was to assess the management of sewage sludge (SS) by composting using fermented water hyacinth (WHferm) as an amendment. The water hyacinth was fermented, and a higher production of volatile fatty acids (VFAs) (782.67 mg L(-1)) and soluble organic carbon (CSOL) (4788.34 mg L(-1)) was obtained using a particle size of 7 mm compared to 50 mm. For composting, four treatments (10 kg fresh weight each) were evaluated: treatment A (100 % SS + 0 % WHferm), treatment B (75 % SS + 25 % WHferm), treatment C (50 % SS + 50 % WHferm), and treatment D (25 % SS + 75 % WHferm). The WHferm added to SS, especially in treatments C (50 %) and D (75 %), increased the initial contents of organic matter (OM), organic carbon (CORG), CSOL, the C/N ratio, and the germination index (GI). The heavy metal content (HMC) (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) at the beginning was below the maximum allowed by USEPA regulations. All of the samples were free of Salmonella sp. from the beginning. The reduction of the CORG, CSOL, total Kjeldahl nitrogen (TKN), and C/N ratio indicated the degradation of the OM by day 198. The treatments with WHferm (B, C, and D) yielded higher values of electrical conductivity, cation exchange capacity, and GI than SS at day 198. No significant differences were observed in GI among the treatments with WHferm. The fecal coliforms were eliminated (<3 MPN g(-1)) and the helminths were reduced to ≤5 eggs/2 g during the process. The competition for nutrients and the presence of suppressive fungi of the genera Penicillium, Rhizopus, Paecilomyces (penicillin producers), and Fusariella isolated from the compost may have promoted the elimination of pathogens since no thermophile temperatures were obtained. WHferm as an amendment in the composting of SS improved the characteristics of the final product, especially when it was used in proportions of 25 and 50 %. An excellent product was obtained in terms of HMC, and the product was B class in terms of pathogens.


Assuntos
Eichhornia/química , Poluentes Ambientais/análise , Esgotos/química , Solo/química , Biodegradação Ambiental , Ácidos Graxos Voláteis/química , Fermentação , Metais Pesados/análise , Nitrogênio , Paecilomyces/fisiologia , Penicillium/fisiologia , Rhizopus/fisiologia , Microbiologia do Solo , Temperatura
20.
Eur J Cell Biol ; 40(2): 219-25, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3709546

RESUMO

The cell surface carbohydrates of Leishmania mexicana amazonensis (amastigotes and promastigotes, both infective and non-infective forms) were comparatively analyzed by agglutination assay employing 28 highly purified lectins, and by binding assay using 125I-labeled lectins. Among the D-GalNAc binding lectins, Bandeiraea simplicifolia-I, Dolichos biflorus, Phaseolus vulgaris and Glycine max were highly specific for the amastigotes, while that from Maclura aurantiaca selectively agglutinated promastigotes. The lectins from Wistaria floribunda, Phaseolus lunatus (D-GalNAc), Arachis hypogaea (D-Gal) and Triticum vulgaris (D-GlcNAc) were selective for the infective forms (both amastigotes and promastigotes), not reacting with the non-infective ones. Conversely, no parasite agglutination occurred with the L-fucose binding lectins Lotus tetragonolobus and Ulex europaeus-I. Binding studies with 125I-labeled lectins from Wistaria floribunda, Triticum vulgaris and Arachis hypogaea were performed to find whether unagglutinated non-infective promastigotes might have receptors for these lectins, in which case absence of agglutination could be due to a peculiar arrangement of the receptors. These assays essentially confirmed the selectivity, demonstrated in the agglutination assays of these lectins for the infective promastigotes.


Assuntos
Leishmania mexicana/análise , Aglutinação , Animais , Carboidratos/análise , Cricetinae , Lectinas , Leishmania mexicana/patogenicidade , Macrófagos/análise , Neuraminidase , Tripsina , Vacúolos/análise
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