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1.
Chem Biol Drug Des ; 103(5): e14530, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38725091

RESUMO

Feline immunodeficiency virus (FIV) is a common infection found in domesticated and wild cats worldwide. Despite the wealth of therapeutic understanding of the disease in humans, considerably less information exists regarding the treatment of the disease in felines. Current treatment relies on drugs developed for the related human immunodeficiency virus (HIV) and includes compounds of the popular non-nucleotide reverse transcriptase (NNRTI) class. This is despite FIV-RT being only 67% similar to HIV-1 RT at the enzyme level, increasing to 88% for the allosteric pocket targeted by NNRTIs. The goal of this project was to try to quantify how well the more extensive pharmacological knowledge available for human disease translates to felines. To this end we screened known NNRTIs and 10 diverse pyrimidine analogs identified virtually. We use this chemo-centric probe approach to (a) assess the similarity between the two related RT targets based on the observed experimental inhibition values, (b) try to identify more potent inhibitors at FIV, and (c) gain a better appreciation of the structure-activity relationships (SAR). We found the correlation between IC50s at the two targets to be strong (r2 = 0.87) and identified compound 1 as the most potent inhibitor of FIV with IC50 of 0.030 µM ± 0.009. This compared to FIV IC50 values of 0.22 ± 0.17 µM, 0.040 ± 0.010 µM and >160 µM for known anti HIV-1 RT drugs Efavirenz, Rilpivirine, and Nevirapine, respectively. This knowledge, along with an understanding of the structural origin that give rise to any differences could improve the way HIV drugs are repurposed for FIV.


Assuntos
Transcriptase Reversa do HIV , Vírus da Imunodeficiência Felina , Inibidores da Transcriptase Reversa , Animais , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/química , Gatos , Vírus da Imunodeficiência Felina/efeitos dos fármacos , Transcriptase Reversa do HIV/antagonistas & inibidores , Transcriptase Reversa do HIV/metabolismo , Humanos , Relação Estrutura-Atividade , Pirimidinas/química , Pirimidinas/farmacologia , Alcinos/química , Alcinos/farmacologia , HIV-1/efeitos dos fármacos , HIV-1/enzimologia , Ciclopropanos/farmacologia , Ciclopropanos/química , Simulação de Acoplamento Molecular , Benzoxazinas/química , Benzoxazinas/farmacologia
3.
Micromachines (Basel) ; 15(5)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38793153

RESUMO

We introduce a micro-electromechanical system (MEMS) energy harvester, designed for capturing flow energy. Moving beyond traditional vibration-based energy harvesting, our approach incorporates a cylindrical oscillator mounted on an MEMS chip, effectively harnessing wind energy through flow-induced vibration (FIV). A highlight of our research is the development of a comprehensive fabrication process, utilizing a 5.00 µm thick cantilever beam and piezoelectric film, optimized through advanced micromachining techniques. This process ensures the harvester's alignment with theoretical predictions and enhances its operational efficiency. Our wind tunnel experiments confirmed the harvester's capability to generate a notable electrical output, with a peak voltage of 2.56 mV at an 8.00 m/s wind speed. Furthermore, we observed a strong correlation between the experimentally measured voltage frequencies and the lift force frequency observed by CFD analysis, with dominant frequencies identified in the range of 830 Hz to 867 Hz, demonstrating the potential application in actual flow environments. By demonstrating the feasibility of efficient energy conversion from ambient wind, our research contributes to the development of sustainable energy solutions and low-power wireless electron devices.

4.
Prev Vet Med ; 226: 106167, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461703

RESUMO

Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are retroviruses of great importance for domestic cats with a worldwide distribution. A retrospective study was conducted to determine the epidemiological and clinicopathological aspects of the infection by FIV and FeLV in cats from the Brazilian semiarid region. Cats treated between 2011 and 2021 at the teaching veterinary hospital of the Federal Rural University of the Semi-Arid Region that were submitted to a point-of-care (POC) test to detect anti-FIV IgG antibodies and FeLV antigen were enrolled in the study. Overall, 454 cats were selected, of which 30.2% [95% CI = 26.0% - 34.3%] were FIV-positive, 1.1% [95% CI = 0.9% - 1.2%] were FeLV-positive, and 0.7% [95% CI = 0.1% - 1.3%] were coinfected by both retroviruses. No statistical association was found between the studied retroviruses (P = 0.144). Multivariable analysis detected significant associations between FIV infection and male sex [OR = 5.7, 95% CI = 3.0-10.7, P < 0.0001), age between 19 and 78 months [OR = 5.2, 95% CI = 2.2-12.1, P < 0.0001], age greater than 78 months [OR = 12.8, 95% CI = 5.1-31.9, P < 0.0001], crossbreed [OR = 4.1, 95% CI = 1.2-13.4, P = 0.021], the presence of oral disease [OR = 2.1, 95% CI = 1.3-3.4, P = 0.004], reduced red blood cell (RBC) count [OR = 3.7, 95% CI = 1.9-7.2, P < 0.0001], and an albumin:globulin (A:G) ratio lower than 0.6 [OR = 3.4, 95% CI = 1.6-7.1, P = 0.001]. No statistical analyses were performed for FeLV infection due to the low number of positive animals. In the quantitative analyses of hematological parameters, FIV-positive cats presented lower values for RBC, hemoglobin, hematocrit, lymphocytes, and platelets compared to the negative animals. In the biochemical profile, cats infected with FIV showed higher creatinine, urea, total protein, and globulin values, while lower values for albumin and A:G ratio were observed (P < 0.05). The findings of this study characterized the prevalence, clinicopathological findings, and risk factors associated with FIV and FeLV in cats from the Brazilian semiarid region. They may help support veterinary practitioners in diagnosing feline retroviruses. The FIV prevalence observed is among the highest reported in Brazil, demonstrating the need for prevention and control strategies for this retrovirus.


Assuntos
Doenças do Gato , Síndrome de Imunodeficiência Adquirida Felina , Globulinas , Vírus da Imunodeficiência Felina , Leucemia Felina , Gatos , Animais , Masculino , Vírus da Leucemia Felina , Brasil/epidemiologia , Estudos Retrospectivos , Leucemia Felina/epidemiologia , Albuminas , Síndrome de Imunodeficiência Adquirida Felina/epidemiologia , Doenças do Gato/epidemiologia
5.
Acta Trop ; 253: 107184, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38479467

RESUMO

Feline Immunodeficiency Virus (FIV) is one of the most important infectious diseases of cats, with potential implications in wildlife conservation. Unfortunately, FIV screening and surveillance in domestic cats remains limited in several African countries, including Namibia. In this study, 279 blood samples from domestic cats in Namibia were analyzed for FIV diagnosis by PCR. The cats represented various regions and were cared for by people largely from rural areas with limited financial means. Only 1.43 % of the samples tested positive, unexpectedly low given their outdoor lifestyles. The infected cats, primarily adult and unsterilized, showed no typical FIV symptoms, suggesting subclinical infections. Genetic analysis of the detected strains indicated a unique FIV strain cluster in Namibia, although with a certain within-country variability, in the absence of consistent geographical clustering. The present study represents the first detection and genetic characterization of FIV in the Namibian domestic cat population. Although the infection frequency was low, also in the rural free-roaming population, the features of the enrolled population could have biased the estimation, suggesting the need for more extensive surveys involving diseased and older cats as well. Additionally, because of the long-lasting subclinical nature of the infection, frequent monitoring activities should be performed that allow prompt isolation of infected animals and the implementation of appropriate control measures if necessary.


Assuntos
Doenças do Gato , Síndrome de Imunodeficiência Adquirida Felina , Vírus da Imunodeficiência Felina , Humanos , Animais , Gatos , Vírus da Imunodeficiência Felina/genética , Síndrome de Imunodeficiência Adquirida Felina/epidemiologia , Animais Selvagens , Análise por Conglomerados , África , Doenças do Gato/epidemiologia
6.
Res Vet Sci ; 168: 105138, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218061

RESUMO

Autologous platelet-rich plasma (PRP) contains growth factors (GFs) that modulate the expression of inflammatory cells; thus, these products could be considered a good strategy to favor tissue regeneration in feline immunodeficiency (FIV) positive cats. However, there is no scientific documentation on obtaining PRP in FIV-positive cats. Authors hypothesized that PRP can be obtained in FIV cats following the PRGF®-Endoret® methodology. The objectives of this study were to compare the platelet, erythrocyte, and leukocyte concentration between whole blood (WB) and the PRP; and determine the concentration of platelet-derived growth factor BB (PDGF-BB) and transforming growth factor ß1 (TGF-ß1) in FIV-positive cats. Sixteen adults FIV-positive asymptomatic cats were included in the study. WB samples were drawn and the PRP was obtained by centrifugation at 265g for 10 min. Erythrocyte and leukocyte, platelets, and mean platelet volume (MPV) were determined both in WB and in PRP. PDGF-BB and TGF-ß1 concentrations were additionally determined in PRP. Platelet concentration increased 1.1 times in PRP fraction compared to WB, but no significant differences were reported. MPV was statistically higher in WB than in PRP (p = 0.001). Erythrocytes and leukocytes counts were decreased by 99% and 92%, respectively in the PRP fraction (p < 0.001). Regarding TGF-ß1, a higher concentration was shown in the PRP (p < 0.02). Although the product obtained could not be classified as PRP according to the PRGF®-Endoret® methodology, based on the drastic reduction of RBC and WBC, the PLT concentrate is of high purity.


Assuntos
Vírus da Imunodeficiência Felina , Plasma Rico em Plaquetas , Gatos , Animais , Becaplermina/metabolismo , Fator de Crescimento Transformador beta1/análise , Fator de Crescimento Transformador beta1/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Plaquetas , Plasma Rico em Plaquetas/química , Plasma Rico em Plaquetas/metabolismo
7.
J Vet Sci ; 24(5): e67, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38031646

RESUMO

BACKGROUND: Feline immunodeficiency virus (FIV) causes an acquired immunodeficiency-like syndrome in cats. FIV is latent. No effective treatment has been developed for treatment the infected cats. The first and second generations non-nucleoside reverse transcriptase inhibitors (NNRTIs) for HIV treatment, nevirapine (NVP) and efavirenz (EFV), and rilpivirine (RPV), were used to investigate the potential of NNRTIs for treatment of FIV infection. OBJECTIVE: This study aims to use experimental and in silico approaches to investigate the potential of NNRTIs, NVP, EFV, and RPV, for inhibition of FIV reverse transcriptase (FIV-RT). METHODS: The FIV-RT and human immunodeficiency virus reverse transcriptase (HIV-RT) were expressed and purified using chromatography approaches. The purified proteins were used to determine the IC50 values with NVP, EFV, and RPV. Surface plasmon resonance (SPR) analysis was used to calculate the binding affinities of NNRTIs to HIV-RT and FIV-RT. The molecular docking and molecular dynamic simulations were used to demonstrate the mechanism of FIV-RT and HIV-RT with first and second generation NNRTI complexes. RESULTS: The IC50 values of NNRTIs NVP, EFV, and RPV against FIV-RT were in comparable ranges to HIV-RT. The SPR analysis showed that NVP, EFV, and RPV could bind to both enzymes. Computational calculation also supports that these NNRTIs can bind with both FIV-RT and HIV-RT. CONCLUSIONS: Our results suggest the first and second generation NNRTIs (NVP, EFV, and RPV) could inhibit both FIV-RT and HIV-RT.


Assuntos
Fármacos Anti-HIV , Doenças do Gato , Infecções por HIV , HIV-1 , Gatos , Animais , Humanos , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/uso terapêutico , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Simulação de Acoplamento Molecular , HIV-1/metabolismo , Rilpivirina/farmacologia , Rilpivirina/uso terapêutico , Nevirapina/farmacologia , Nevirapina/uso terapêutico , Transcriptase Reversa do HIV/metabolismo , Transcriptase Reversa do HIV/farmacologia , Transcriptase Reversa do HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/veterinária , Doenças do Gato/tratamento farmacológico
8.
Front Vet Sci ; 10: 1260081, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026675

RESUMO

Introduction: Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are well-known retroviruses causing important infections in domestic cats worldwide. The goal of this study was to determine the prevalence of FeLV and FIV infections in cat living indoor and outdoor in southern Italy. Methods: The survey was conducted on 1322 stray and owned cats from the regions of Campania, Basilicata, and Calabria. It was carried out over a 10-year period to obtain a more realistic picture of the prevalence of these retroviral diseases in the country. FIV and FeLV status was determined by enzyme-linked immunosorbent assay (ELISA) using a commercial kit (SNAP Combo Plus FeLV/FIV, IDEXX). Risk factors were analysed by logistic regression. Results and Discussion: The results showed that 101/1322 (7.64%) cats were positive for FeLV antigen and 110/1322 (8.32%) cats were positive for FIV antibody. Twenty-six of the 1322 cats (1.97%) were positive for both FIV and FeLV infection. Our results are similar to those published in recent studies in Europe. A statistically significant association (p < 0.05) was found between year, province, region, lifestyle and risk of FeLV infection. FIV positivity was instead statistically associated only with year and lifestyle.

9.
Animals (Basel) ; 13(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37627457

RESUMO

Feline lymphoma is currently less commonly associated with retrovirus infections as the feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV). This is thought to have caused a shift in the distribution of anatomical subtypes and eventually have led to poorer treatment outcomes. The aim of this study was to evaluate whether this change was also notable in the Netherlands, a country historically known for its low prevalence of FeLV and FIV, and to determine its consequences on treatment response. A 10-year cohort of 174 cats with large cell lymphoma (110 treated) were included and compared to historical data from previously published reports in the Netherlands. Of the 90 cats screened, only one tested positive for FeLV and three for FIV. The most current cohort had an increased age (median 8.7 years) and fever Siamese cats (6.3%) compared to previous reports, with alimentary (24.5%) and nasopharyngeal lymphoma (22.7%) being the most common subtypes. Sixty-six of the one hundred and ten cats (60%) went into complete remission, (CR) resulting in a median disease-free period (DFP) of 763 days, with nasopharyngeal and mediastinal having the longest DFP. The median overall survival time was 274 days with an estimated 1-year survival of 41.3% and a 2-year survival of 34.6%, respectively. Patient characteristics of cats with malignant lymphoma in the Netherlands have changed over the years, but this cannot be explained by differences in FeLV/FIV prevalence. Although the overall response rate to therapy did not change over time, for some lymphoma subtypes, longer DFPs were observed compared to 30 years ago.

10.
Viruses ; 15(8)2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37632117

RESUMO

Feline immunodeficiency virus (FIV) is a lentivirus in the family Retroviridae that infects domestic cats resulting in an immunodeficiency disease featuring a progressive and profound decline in multiple sets of peripheral lymphocytes. Despite compelling evidence of FIV-associated immunopathology, there are conflicting data concerning the clinical effects of FIV infection on host morbidity and mortality. To explore FIV-associated immunopathogenesis and clinical disease, we experimentally inoculated a cohort of four specific pathogen-free kittens with a biological isolate of FIV clade C and continuously monitored these animals along with two uninfected control animals for more than thirteen years from the time of inoculation to the humane euthanasia endpoint. Here, we report the results obtained during the late asymptomatic and terminal phases of FIV infection in this group of experimentally FIV-infected cats.


Assuntos
Vírus da Imunodeficiência Felina , Síndromes de Imunodeficiência , Gatos , Animais , Feminino , Lentivirus , Estudos Longitudinais , Retroviridae
11.
Infect Agent Cancer ; 18(1): 40, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386451

RESUMO

Currently, it is estimated that 15% of human neoplasms globally are caused by infectious agents, with new evidence emerging continuously. Multiple agents have been implicated in various forms of neoplasia, with viruses as the most frequent. In recent years, investigation on viral mechanisms underlying tumoral transformation in cancer development and progression are in the spotlight, both in human and veterinary oncology. Oncogenic viruses in veterinary medicine are of primary importance not only as original pathogens of pets, but also in the view of pets as models of human malignancies. Hence, this work will provide an overview of the main oncogenic viruses of companion animals, with brief notes of comparative medicine.

12.
Front Neurosci ; 17: 1151823, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37179549

RESUMO

Objectives: We used two automated software commonly employed in clinical practice-Olea Sphere (Olea) and Shukun-PerfusionGo (PerfusionGo)-to compare the diagnostic utility and volumetric agreement of computed tomography perfusion (CTP)-predicted final infarct volume (FIV) with true FIV in patients with anterior-circulation acute ischemic stroke (AIS). Methods: In all, 122 patients with anterior-circulation AIS who met the inclusion and exclusion criteria were retrospectively enrolled and divided into two groups: intervention group (n = 52) and conservative group (n = 70), according to recanalization of blood vessels and clinical outcome (NIHSS) after different treatments. Patients in both groups underwent one-stop 4D-CT angiography (CTA)/CTP, and the raw CTP data were processed on a workstation using Olea and PerfusionGo post-processing software, to calculate and obtain the ischemic core (IC) and hypoperfusion (IC plus penumbra) volumes, hypoperfusion in the conservative group and IC in the intervention group were used to define the predicted FIV. The ITK-SNAP software was used to manually outline and measure true FIV on the follow-up non-enhanced CT or MRI-DWI images. Intraclass correlation coefficients (ICC), Bland-Altman, and Kappa analysis were used to compare the differences in IC and penumbra volumes calculated by the Olea and PerfusionGo software to investigate the relationship between their predicted FIV and true FIV. Results: The IC and penumbra difference between Olea and PerfusionGo within the same group (p < 0.001) was statistically significant. Olea obtained larger IC and smaller penumbra than PerfusionGo. Both software partially overestimated the infarct volume, but Olea significantly overestimated it by a larger percentage. ICC analysis showed that Olea performed better than PerfusionGo (intervention-Olea: ICC 0.633, 95%CI 0.439-0.771; intervention-PerfusionGo: ICC 0.526, 95%CI 0.299-0.696; conservative-Olea: ICC 0.623, 95%CI 0.457-0.747; conservative-PerfusionGo: ICC 0.507, 95%CI 0.312-0.662). Olea and PerfusionGo had the same capacity in accurately diagnosing and classifying patients with infarct volume <70 ml. Conclusion: Both software had differences in the evaluation of the IC and penumbra. Olea's predicted FIV was more closely correlated with the true FIV than PerfusionGo's prediction. Accurate assessment of infarction on CTP post-processing software remains challenging. Our results may have important practice implications for the clinical use of perfusion post-processing software.

13.
Rev. iberoam. fertil. reprod. hum ; 40(1): 27-36, enero-febrero-marzo-abril 2023. tab
Artigo em Espanhol | IBECS | ID: ibc-220191

RESUMO

Introducción: En los últimos años, los tratamientos de FIV en ciclo natural y la FIV con estimulación ovárica “suave” están resurgiendo como una opción más segura, económica y cómoda para las pacien-tes. Definimos FIV en ciclo natural como el tratamiento en el que los ovocitos son obtenidos de un ciclo ovulatorio espontáneo. Cuando añadimos fármacos orales (citrato de clomifeno o letrozol), hablamos de estimulación “mínima”. El objetivo de este estudio es clarificar si la introducción de esta medicación es beneficiosa para las pacientes. Materials y métodos: Analizamos retrospectivamente los tratamientos de FIV en ciclo natural o con estimulación mínima llevados realizados en nuestro centro de enero 2016 a diciembre 2020.Resultados: Encontramos diferencias significativas entre los dos protocolos en el número de ovocitos obtenidos después de la punción folicular (1.03 vs 1.63, p<0.001), número de ovocitos maduros (0.9 vs 1.3, p < 0.01), ovocitos fecundados (0.7 vs 1.1, p < 0.01), y número de embriones disponibles para trans-ferencia (0.5 vs 0.7, p < 0.01). Sin embargo, no encontramos diferencias en la tasa de embarazo (26,3% vs 19,6%, p=0.251) ni en la tasa de recién nacido vivo (16.3% vs 14,3%, p=0.7806).Discusión: Añadir medicación oral a la FIV en ciclo natural no parece tener ningún impacto sobre los resultados clínicos del ciclo. Son necesarios más estudios, pero podríamos reconsiderar la necesidad de añadir esta medicación, ya que supone un mayor coste para los pacientes. (AU)


Introduction: In recent years, natural cycle IVF and minimal ovarian stimulation IVF had been under-going a revival, gaining recognition as safer, cheaper, and more comfortable options for patients. We define natural cicle IVF as the treatment in which oocytes are obtained from a spontaneous ovulatory cycle. When oral drugs are used (usually clomiphene citrate or letrozole), the process is referred to as minimal ovarian stimulation cycle IVF. The aim of this study is to clarify whether the introduction of oral medication is beneficial for patients.Methods: We retrospectively analysed all natural or minimal ovarian stimulation IVF treatments that took place in our clinic during the studied period (January 2016 - December 2020). Descriptive variables were analysed with a t-test, and a chi-square test was performed on result variables. Results: We found significant differences, between both protocols, in the number of oocytes obtained after oocyte retrieval (1.03 vs 1.63, p<0.001), number of mature oocytes (0.9 vs 1.3, p < 0.01), fertilized oocytes (0.7 vs 1.1, p < 0.01), and number of embryos available for transfer (0.5 vs 0.7, p < 0.01).Howe-ver, we did not found signficant differences in terms of pregnancy rate (26,3% vs 19,6%, p=0.251) or live birth rate (16.3% vs 14,3%, p=0.7806). (AU)


Assuntos
Humanos , Esquema de Medicação , Terapêutica , Oócitos
14.
Gynecol Obstet Fertil Senol ; 51(5): 249-255, 2023 05.
Artigo em Francês | MEDLINE | ID: mdl-36871830

RESUMO

OBJECTIVES: To evaluate the impact of adding a GnRH agonist (GnRH-a) in luteal phase support (LPS) on live birth rates in IVF/ICSI in antagonist protocols. METHODS: In total, 341 IVF/ICSI attempts are analyzed in this retrospective study. Patients were divided into two groups: A f: LPS with progesterone alone (179 attempts) between March 2019 and May 2020; B: LPS with progesterone and an injection of triptorelin (GnRH-a) 0.1mg 6 days after oocyte retrieval (162 attempts) between June 2020 and June 2021. The primary outcome was live birth rate. The secondary outcomes were miscarriage rate, pregnancy rate and ovarian hyperstimulation syndrome rate. RESULTS: The baseline characteristic are identical between the two groups except the infertility duration (longer in the group B). There was no significant difference between the two groups in live birth rate (24.1% versus 21.2%), pregnancy rate (33.3% versus 28.1%), miscarriage rate (4.9% versus 3.4%) and no increase the SHSO rate. The multivariate regression analysis after adjustment for age, ovarian reserve and infertility duration did not reveal a significant difference in live birth rate between the two groups. CONCLUSION: In this study, the results showed no statistically significant association with the single injection of a GnRH-a in addition to progesterone on live birth rate in luteal phase support.


Assuntos
Aborto Espontâneo , Infertilidade , Gravidez , Feminino , Humanos , Progesterona , Coeficiente de Natalidade , Hormônio Liberador de Gonadotropina , Estudos Retrospectivos , Aborto Espontâneo/epidemiologia , Fase Luteal/fisiologia , Lipopolissacarídeos , Taxa de Gravidez , Indução da Ovulação/métodos , Fertilização in vitro/métodos
15.
mBio ; 14(2): e0016123, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36927083

RESUMO

Signal peptides are N-terminal peptides, generally less than 30 amino acids in length, that direct translocation of proteins into the endoplasmic reticulum and secretory pathway. The envelope glycoprotein (Env) of the nonprimate lentivirus feline immunodeficiency virus (FIV) contains the longest signal peptide of all eukaryotic, prokaryotic, and viral proteins (175 amino acids), yet the reason is unknown. Tetherin is a dual membrane-anchored host protein that inhibits the release of enveloped viruses from cells. Primate lentiviruses have evolved three antagonists: the small accessory proteins Vpu and Nef, and in the case of HIV-2, Env. Here, we identify the FIV Env signal peptide (Fsp) as the FIV tetherin antagonist. A short deletion in the central portion of Fsp had no effect on viral replication in the absence of tetherin, but severely impaired virion budding in its presence. Fsp is necessary and sufficient, acting as an autonomous accessory protein with the rest of Env dispensable. In contrast to primate lentivirus tetherin antagonists, its mechanism is to stringently block the incorporation of this restriction factor into viral particles rather than by degrading it or downregulating it from the plasma membrane. IMPORTANCE The study of species- and virus-specific differences in restriction factors and their antagonists has been central to deciphering the nature of these key host defenses. FIV is an AIDS-causing lentivirus that has achieved pandemic spread in the domestic cat. We now identify its tetherin antagonist as the signal sequence of the Envelope glycoprotein, thus identifying the fourth lentiviral anti-tetherin protein and the first new lentiviral accessory protein in decades. Fsp is necessary and sufficient and functions by stringently blocking particle incorporation of tetherin, which differs from the degradation or surface downregulation mechanisms used by primate lentiviruses. Fsp also is a novel example of signal peptide dual function, being both a restriction factor antagonist and a mediator of protein translocation into the endoplasmic reticulum.


Assuntos
Vírus da Imunodeficiência Felina , Lentivirus de Primatas , Animais , Gatos , Vírus da Imunodeficiência Felina/genética , Vírus da Imunodeficiência Felina/metabolismo , Antígeno 2 do Estroma da Médula Óssea/genética , Sinais Direcionadores de Proteínas , Sequência de Aminoácidos , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Aminoácidos , Proteínas do Vírus da Imunodeficiência Humana/metabolismo , Proteínas Virais Reguladoras e Acessórias/genética
16.
Viruses ; 15(2)2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36851705

RESUMO

Different feline leukemia virus (FeLV) infection outcomes are possible in cats following natural exposure, such as progressive infections (persistent viremia), regressive infections (transient or no viremia followed by proviral persistence) and abortive infections (presence of only antibodies). Laboratory-based testing is currently required for categorization of infection outcomes in cats. The aim of this study was to evaluate the field performance of a novel, rapid, combination point-of-care (PoC) test kit commercially available in Europe (v-RetroFel®Ag/Ab; 2020-2021 version) to determine different FeLV infection outcomes by concurrent detection of FeLV antigen (p27) and antibodies against FeLV transmembrane envelope protein (p15E). A secondary aim was to evaluate the performance of the same test kit (v-RetroFel®FIV) to determine positive/negative feline immunodeficiency virus (FIV) infection status by the detection of antibodies to FIV capsid protein (p24) and transmembrane glycoprotein (gp40). Two cohorts of domestic cats were recruited and tested with v-RetroFel® using plasma or serum, including cats in Australia (n = 200) and cats in Germany (n = 170). Results from p27 antigen PoC testing, proviral DNA PCR, and neutralizing antibody testing or testing for antibodies against non-glycosylated surface unit envelope protein (p45) were used to assign cats to groups according to different FeLV infection outcomes. Testing with a laboratory-based FeLV p15E antibody ELISA was also performed for comparison. In the first cohort, v-RetroFel®Ag/Ab correctly identified 89% (109/122) FeLV-unexposed cats and 91% (21/23) progressive infections, but no regressive (0/23) or abortive (0/32) infections. In the second cohort, v-RetroFel®Ag/Ab correctly identified 94% (148/158) FeLV-unexposed cats and 100% (4/4) progressive infections, but no regressive (0/2) and only 17% (1/6) abortive infections. There was test agreement between v-RetroFel®Ab and the p15E laboratory ELISA in 58.9% of samples. As a secondary outcome of this study, the sensitivity and specificity of v-RetroFel®FIV testing in cohort 1 were 94.7% (18/19) and 98.3% (178/181), and in cohort 2, 30.0% (3/10) and 100.0% (160/160), respectively. Prior history of FIV vaccination did not produce any false-positive FIV results. In conclusion, v-RetroFel®Ag/Ab (2020-2021 version) was unable to accurately determine different FeLV infection outcomes in the field. Improvements of the test prior to application to field samples are required.


Assuntos
Vírus da Leucemia Felina , Leucemia Felina , Gatos , Animais , Alemanha , Leucemia Felina/diagnóstico , Leucemia Felina/epidemiologia , Austrália/epidemiologia , Anticorpos Neutralizantes , Proteínas de Membrana
17.
Gynecol Obstet Fertil Senol ; 51(3): 157-165, 2023 03.
Artigo em Francês | MEDLINE | ID: mdl-36529380

RESUMO

OBJECTIVE: Many studies in the literature have found an association between geographic origin and poorer IVF outcomes in African American and Asian minority populations compared with Caucasian populations. The limitations of these studies are multiple (inconsistencies in the characterization of ethnic groups, mostly multicenter studies with large variability in success rates between centers, minorities having more limited and delayed access to care). Thus, socioeconomic status may have been an important bias in judging environmental or "genetic" factors. The objective of our study is to determine whether geographic origin would influence IVF response and outcomes in a French university hospital center with equal access to care. MATERIAL AND METHODS: This was a retrospective single-center observational study from January 2013 to January 2020 comparing IVF response in 3 populations of similar size at our Medically Assisted Reproduction center, with all charges covered by Medicare. The primary objective was ovarian response to IVF, and the secondary objectives were clinical pregnancy rate and live birth rate per cycle started. RESULTS: We analyzed 1669 cycles of first IVF attempt in women from Europe (525), Sub-Saharan Africa (649) and Maghreb (495). The SSA and Maghrebi women had a higher BMI. SSA women were more often affected by tubal or uterine infertility, HIV or HBV infection, and were less often nulliparous. The indication of male infertility was more frequent in Maghrebi women with a higher ICSI rate. There was no significant difference in the duration of stimulation, endometrial thickness at induction, number of oocytes collected, fertilization rate, number of embryos transferred and frozen. Nevertheless, the cancellation rate was higher in SSA and Maghrebi women and the total dose of gonadotropins was higher in SSA. No significant difference was found between Maghrebi and European women on IVF outcomes except for a lower number of total embryos in Maghrebi women (3.33 vs. 4.13 on average, P<0.001). The SSA had a lower rate of mature oocytes per puncture (66 % vs. 73 %, P<0.001), a lower number of total embryos per puncture (3.56 vs. 4.13 on average, P<0.016), a lower rate of clinical pregnancies per cycle (11.7% vs. 20.4%, P<0.001), a lower rate of live births per cycle (6.9% vs. 15.2%, P<0.001). CONCLUSION: There was no significant difference between European and Maghrebi women at the end of IVF, but the results were lower for those from SSA.


Assuntos
Fertilização in vitro , Infertilidade Masculina , Idoso , Estados Unidos , Gravidez , Masculino , Feminino , Humanos , Fertilização in vitro/métodos , Estudos de Coortes , Estudos Retrospectivos , Medicare , Taxa de Gravidez , Europa (Continente) , Infertilidade Masculina/terapia , África Subsaariana/epidemiologia , Indução da Ovulação/métodos
18.
Vet. zootec ; 30: 1-9, 2023. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1513212

RESUMO

O objetivo deste estudo foi avaliar o efeito da inclusão de cilostazol no meio de maturação in vitro de oócitos sobre produção in vitro de embriões ovinos. Para isso, foram realizadas colheitas de oócitos oriundos de ovários obtidos em abatedouro por meio do método de aspiração folicular com bomba de vácuo. Os oócitos foram divididos em quatro grupos de maturação: grupo CON, onde os complexos cumulus oócitos foram imersos em TCM-199, suplementado com 500 UI de penicilina, 0,5 mg de estreptomicina, 1,25 µg de anfotericina, 0,2 mM de piruvato de sódio, 10% (v/v) de soro fetal bovino (SFB), 10 ng/mL de fator de crescimento epidérmico (EGF), 10 ug/m de FSH, 10 µg/mL de LH, 10 ug/mL de estradiol e 100 µM de cisteamina; e nos grupos CILO0,3; CILO1 e CILO10, os oócitos foram maturados no meio do grupo CON, mas sem a adição de cisteamina e suplementado com as concentrações de 0,3; 1 e 10 µM, respectivamente. Após 24h, os oócitos foram avaliados quanto a presença ou não de células do cumulus e quanto ao grau de expansão e destinados à fecundação in vitro, em meio FIV, juntamente com espermatozoides. Após a FIV, os presumíveis zigotos seguiram para o cultivo in vitro. Foram avaliadas clivagens no dia 2, sendo dia 0 o dia do início do CIV. Os resultados foram expressos em porcentagem e as variáveis de expansão das células do cumulus e número de estruturas clivadas foram comparadas por meio do teste qui-quadrado do software Epi Info (Epi Info 7.2.5, Atlanta, GA, EUA, 2021). Os resultados foram considerados significativos quando P<0,05. Em relação à expansão das células do cumulus, todos os grupos apresentaram 100% de expansão. Não houve diferenças significativas quanto ao grau de expansão das células do cumulus entre os grupos suplementados com cilostazol e cisteamina (P>0,05), assim como não houve diferenças significativas entre as taxas de clivagem entre os grupos suplementados com cilostazol e cisteamina (P > 0,05).


The objective of this study was to evaluate the effect of including cilostazol in the in vitro maturation medium of oocytes on the in vitro production of sheep embryos. Oocytes were collected from ovaries obtained from a slaughterhouse by follicular aspiration with a vacum pump. The oocytes were divided into four maturation groups: the CON group, where the cumulus-oocyte complexes were immersed in TCM-199 supplemented with 500 IU of penicillin, 0.5 mg of streptomycin, 1.25 µg of amphotericin, 0.2 mM of sodium pyruvate, 10% (v/v) fetal bovine serum (FBS), 10 ng/mL of epidermal growth factor (EGF), 10 µg/mL of FSH, 10 µg/mL of LH, 10 µg/mL of estradiol, and 100 µM of cysteamine; and in the CILO0.3, CILO1, and CILO10 groups, the oocytes were matured in the CON group medium without the addition of cysteamine and supplemented with concentrations of 0.3, 1, and 10 µM of cilostazol, respectively. After 24 hours, the oocytes were evaluated for the presence or absence of cumulus cells and the degree of expansion and then subjected to in vitro fertilization (IVF) with sperm in FIV medium. After IVF, the presumptive zygotes were cultured in vitro. Cleavage was evaluated on day 2, with day 0 being the start of IVF. Results were expressed as a percentage, and variables such as cumulus cell expansion and the number of cleaved structures were compared using the chi-square test in the Epi Info software (Epi Info 7.2.5, Atlanta, GA, USA, 2021). Results were considered significant when P < 0.05. All groups showed 100% cumulus cell expansion, and there were no significant differences in cumulus cell expansion degree between the cilostazol- and cysteamine-supplemented groups (P > 0.05), as well as no significant differences in cleavage rates between the cilostazol- and cysteamine-supplemented groups (P > 0.05).


El objetivo de este estudio fue evaluar el efecto de la inclusión de cilostazol en el medio de maduración in vitro de ovocitos sobre la producción in vitro de embriones ovinos. Para ello, se realizaron recolecciones de ovocitos provenientes de ovarios obtenidos en un matadero mediante el método de aspiración folicular con bomba de vacío. Los ovocitos se dividieron em cuatro grupos de maduración: grupo CON, donde los complejos cúmulus ovocitos se sumergieron en TCM-199, suplementado con 500 UI de penicilina, 0,5 mg de estreptomicina, 1,25 ug de anfotericina, 0,2 mM de piruvato de sodio, 10% (v/v) de suero fetal bovino (SFB), 10 ng/mL de factor de crecimiento epidérmico (EGF), 10 ug/m de FSH, 10 µg/mL de LH, 10 µg/mL de estradiol y 100 µM de cisteamina; y en los grupos CILO0,3; CILO1 y CILO10, los ovocitos se maduraron en el medio del grupo CON, pero sin la adición de cisteamina y suplementado con las concentraciones de 0,3; 1 y 10 µM, respectivamente. Después de 24 horas, los ovocitos se evaluaron en cuanto a la presencia o no de células del cúmulus y em cuanto al grado de expansión y se destinaron a la fecundación in vitro, en medio FIV, junto con espermatozoides. Después de la FIV, los presuntos cigotos siguieron para el cultivo in vitro. Se evaluaron las clivajes en el día 2, siendo el día 0 el día del início del CIV. Los resultados se expresaron en porcentaje y las variables de expansión de las células del cúmulos y número de estructuras clivadas se compararon mediante la prueba del chi-cuadrado del software Epi Info (Epi Info 7.2.5, Atlanta, GA, EE. UU., 2021). Los resultados se consideraron significativos cuando P < 0,05. En relación a la expansión de las células del cúmulus, todos los grupos presentaron el 100% de expansión. No hubo diferencias significativas en cuanto al grado de expansión de las células del cúmulus entre los grupos suplementados con cilostazol y cisteamina (P > 0.05), así como no hubo diferencias significativas entre las tasas de clivaje entre los grupos suplementados con cilostazol y cisteamina (P>0,05).


Assuntos
Animais , Ovinos/fisiologia , Cisteamina/análise , Cilostazol/administração & dosagem , Cilostazol/análise , Vírus da Imunodeficiência Felina , Técnicas de Maturação in Vitro de Oócitos/veterinária
19.
Microorganisms ; 12(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38257898

RESUMO

The aim of this study was to investigate the coinfection of feline retroviruses (feline immunodeficiency virus-FIV, and the feline leukemia virus-FeLV) with Leishmania infantum and Toxoplasma gondii and the factors associated with these pathogens in domestic cats from Mossoró, a city endemic for canine and human leishmaniasis situated in the semiarid region of Northeast Brazil. Blood samples from 120 cats were collected, and an epidemiological questionnaire was applied to investigate the risk factors associated with the infections. Retroviruses, L. infantum, and T. gondii infections were assessed using a point-of-care ELISA and quantitative PCR (qPCR), indirect fluorescent antibody test (IFAT) and qPCR, and IFAT, respectively. The overall seroprevalences observed were 35% (95% CI = 27.0-43.8%) for FIV, 0.8% (95% CI = 0.1-4.5%) for FeLV, 25.8% (95% CI = 18.8-34.3%) for T. gondii, and 4.2% (95% CI = 1.7-9.3%) for L. infantum. Coinfection with FIV and L. infantum was observed in 2.5% (3/120) of the assessed cats, while 12.5% (15/120) were coinfected with FIV and T. gondii. No significant association was found among the investigated agents (p > 0.05). The factors associated with FIV infection in the multivariable analysis were male sex and age above 78 months. The findings of this study demonstrated a high rate of FIV infection in cats from the Brazilian semiarid region and the exposure of these animals to zoonotic and opportunistic agents. Due to the immunosuppressive potential of FIV, cats infected with this retrovirus should be screened for coinfections with L. infantum and T. gondii, and preventative measures should be adopted.

20.
Animals (Basel) ; 12(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36552398

RESUMO

This study was initiated in 2004 because the prevalence of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) infections in feral cats in San Mateo County (SMC) was not known. The cities attributed to the feral cat population presented to the Peninsula Humane Society & SPCA's Spay/Neuter Clinic and to the Shelter itself were analyzed to examine potential geographic concentrations of feral cats with positive retroviral status. Trends in FIV and FeLV status were examined in three 3-year periods (2001−2003, 2005−2007, and 2014−2016). Population trends over the 15 years of this study for feral cats admitted to the Shelter were also examined. In each study period, more female feral cats were presented to the S/N Clinic (54.06%, 57.37%, 54.89%). FIV prevalence increased from 5.52% to 6.41% (p = 0.29) from the first to third period; FeLV prevalence decreased significantly from 1.73% to 0.29% (p = 0.01). Significantly more FIV-positive males than females were identified each year and for each period (p < 0.01). The four largest SMC cities were the major source of feral cats to the Shelter, S/N Clinic, and of FIV- and FeLV-positive cats in the first two periods; in the third period, 50% of feral cats to the Shelter and of FeLV-positive cats were from these cities. Despite a 61.63% reduction in feral cat admissions to the S/N Clinic, the FIV prevalence for males remained similar and increased for females. The retrovirus prevalence suggests the need for continued testing and surveillance of FIV among SMC free-living cats.

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