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1.
Sci Rep ; 13(1): 8206, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-37217674

RESUMO

The behavioral immune system, with disgust as its motivational part, serves as the first line of defense in organisms' protection against pathogens. Laboratory studies indicate that disgust sensitivity adaptively adjusts to simulated environmental threat, but whether disgust levels similarly change in response to real-life threats, such as a pandemic, remains largely unknown. In a preregistered within-subject study, we tested whether the threat posed by the Covid-19 pandemic would lead to increased perceived disgust. The perception of threat was induced by testing during two phases of the Covid-19 pandemic (periods of high vs. low pathogen threat). We found heightened levels of moral disgust during a "wave" of the pandemic, but the effect was not observed in the domain of pathogen or sexual disgust. Moreover, the age of respondents and levels of trait anxiety were positively associated with pathogen and moral disgust, suggesting that variation in disgust sensitivity may be based chiefly on stable characteristics.


Assuntos
COVID-19 , Asco , Humanos , Emoções/fisiologia , Pandemias , Princípios Morais
2.
Horm Behav ; 152: 105360, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37062114

RESUMO

Elevated levels of nausea and vomiting in pregnancy (NVP) and disgust sensitivity have been observed in the first trimester and both are thought to have a protective function for the mother and her fetus. Their aetiology is not clear, however, with previous studies attributing elevated NVP and disgust to various factors including endocrine changes, immunological changes, and psychological variables. To date, no study has directly assessed the relationship between disgust and NVP. Here, we prospectively collected two independent samples (S1 and S2; n1 = 201, n2 = 391) of women in the first trimester of pregnancy, who completed the Index of Nausea, Vomiting, and Retching and the Disgust Scale-Revised. We also measured free ß-human chorionic gonadotropin (hCG) and pregnancy-associated plasma protein A (PAPP-A) in maternal serum. Our results did not confirm any association between NVP and disgust; in addition, they indicate that NVP and disgust may have different proximate causes. Disgust sensitivity was significantly negatively correlated with free ß-hCG and (only in S1) with PAPP-A. In contrast, NVP was significantly positively associated with free ß-hCG levels and (only in S1) with PAPP-A. While low hCG levels seem to be an important indicator for activation of the behavioral immune system in the first trimester, increased hCG levels play a role in stronger symptoms of NVP, a result consistent with previous studies. Levels of PAPP-A are likely part of a larger network of immunological and endocrine responses and do not appear to provide sufficient information for predicting women's NVP and disgust sensitivity.


Assuntos
Asco , Complicações na Gravidez , Feminino , Humanos , Gravidez , Biomarcadores , Gonadotropina Coriônica Humana Subunidade beta , Náusea/etiologia , Primeiro Trimestre da Gravidez , Proteína Plasmática A Associada à Gravidez/metabolismo , Vômito/etiologia
3.
Front Psychol ; 14: 1015927, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923149

RESUMO

Introduction: Considered a part of the behavioral immune system (BIS), disgust sensitivity is expected to be adjusting as a response to the actual level of the environmental health risks. Methods: In this preregistered study, we tested the hypothesis that disgust sensitivity would be higher during the COVID-19 pandemic compared to the pre-pandemic period in pregnant women. In this between-subject study with a longitudinal trend design, we administered the Disgust Scale-Revised to 200 pregnant women before the pandemic and to 350 pregnant women during the pandemic. Results: We found a small but significant effect of the pandemic on disgust sensitivity, such that higher disgust sensitivity was found in women pregnant during the pandemic. This effect was stronger in primiparae, however, the interaction between parity and the pandemic period was not significant. Disgust sensitivity decreased with age. No differences in terms of nausea and vomiting were found between the women pregnant before and during the pandemic. Discussion: Our findings indicate that although BIS is presumed to function as a complex mechanism to prevent health-threatening behaviors, its activation in pregnant women during the COVID-19 pandemic is rather weak.

4.
Sci Rep ; 13(1): 4752, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36959238

RESUMO

Disgust is an essential part of the behavioral immune system, protecting the individual from infection. According to the Compensatory Prophylaxis Hypothesis (CPH), disgust sensitivity increases in times of immunosuppression, potentially including pregnancy. We aimed to replicate a previous study observing longitudinal changes in disgust sensitivity in pregnant women. Additionally, for the first time, we explored how recent health problems influence these changes. To do this, we obtained disgust sensitivity measures from 94 women in each trimester and in early postpartum. In contrast to the original study, where disgust sensitivity was highest in the first trimester, we found that overall and animal reminder disgust increased across pregnancy and after birth. In line with the CPH, women who were recently sick in the first trimester had elevated disgust sensitivity at that time. Although disgust sensitivity was significantly higher in the second trimester and postpartum period compared to the first trimester in mothers pregnant with a male fetus, the overall results regarding the effect of fetus sex on disgust sensitivity were mixed. It seems that changing levels of disgust sensitivity during pregnancy and postpartum result from a suite of physiological and psychological changes that occur during this sensitive period of a woman's life.


Assuntos
Asco , Gravidez , Feminino , Masculino , Humanos , Período Pós-Parto , Gestantes/psicologia , Trimestres da Gravidez , Parto
5.
J Infect ; 86(1): 60-65, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36347427

RESUMO

OBJECTIVES: Toxoplasma gondii is a widely prevalent protozoan parasite in human populations. This parasite is thought to be primarily transmitted through undercooked meat and contamination by cat feces. Here, we seek to determine if Toxoplasma gondii cysts can be found within human semen. METHODS: We used a mixture of histological and immunofluorescence stains to visualize Toxoplasma gondii cysts in thin smears of human semen. Further, we probed for presence of bradyzoite-specific mRNA transcription using in-situ hybridization. RESULTS: We visualized Toxoplasma gondii cysts in ejaculates of immune-competent and latently infected human volunteers. We confirmed the encystment by probing transcription of a bradyzoite-specific gene in these structures. These observations extend previous observations of the parasite in semen of several non-human host species, including rats, dogs, and sheep. CONCLUSIONS: Toxoplasma gondii infection is a clinically significant infection, in view of its high prevalence, its purported role in neuropsychiatric disorders such as schizophrenia, as well as in the more serious form of congenital toxoplasmosis. Our demonstration of intact Toxoplasma gondii cysts in the ejaculate supports the possibility of sexual transmission of the parasite and provides an impetus for further investigations.


Assuntos
Toxoplasma , Toxoplasmose , Humanos , Animais , Ovinos , Ratos , Cães , Toxoplasma/genética , Sêmen/parasitologia , Toxoplasmose/parasitologia , Comportamento Sexual , Fezes
6.
Front Psychol ; 13: 1000753, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36524175

RESUMO

Women with red hair color, i.e., 1-9% of female Europeans, tend to be the subject of various stereotypes about their sexually liberated behavior. The aim of the present case-control study was to explore whether a connection between red hair color and sexual behavior really exists using data from 110 women (34% redheaded) and 93 men (22% redheaded). Redheadedness in women, correlated with various traits related to sexual life, namely with higher sexual desire as measured by Revised Sociosexual Orientation Inventory, with higher sexual activity and more sexual partners of the preferred gender over the past year, earlier initiation of sexual life, and higher sexual submissiveness. Structural equation modelling, however, showed that sexual desire of redheaded women mediated neither their higher sexual activity nor their higher number of sexual partners. These results indirectly indicate that the apparently more liberated sexual behavior in redheaded women could be the consequence of potential mates' frequent attempts to have sex with them. Our results contradicted the three other tested models, specifically the models based on the assumption of different physiology, faster life history strategy, and altered self-perception of redheaded women induced by stereotypes about them. Naturally, the present study cannot say anything about the validity of other potential models that were not subjects of testing.

7.
Psychoneuroendocrinology ; 135: 105451, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34741980

RESUMO

According to the congruency hypothesis, relationship satisfaction is predicted by the congruency (or non-congruency) between current use of oral contraceptives (OC) and their use during relationship formation. This is based on findings that OC may alter women's mate preferences, so that attraction to their partner may have changed in non-congruent women. Indeed, some studies find that women in a non-congruent state were less sexually satisfied with their partner, although they were more satisfied in non-sexual aspects of the relationship. However, some other studies have produced null results, calling the hypothesis into question. In this study, we tested the congruency hypothesis in two samples of pregnant women, and in two samples of couples attending a fertility clinic. In all four samples, couples completed questionnaires on relationship and sexual satisfaction and the women also reported their previous and current contraceptive use. In one sample of pregnant women, we found that women who used OC during relationship formation were more sexually satisfied with their partner compared to women who did not use OC at that time; this pattern has previously been interpreted as supporting the congruency hypothesis in view of certain similarities in hormonal profile between OC use and pregnancy. We did not find any significant effect of OC use during relationship formation on sexual and relationship satisfaction in the other sample of pregnant women, either sample attending the fertility clinic, or in the male partners of any of our samples. Our results thus provide mixed support for the congruency hypothesis. Finally, we discuss recommendations for future studies such as use of within-subject designs and more structured assessment of sexual satisfaction.


Assuntos
Anticoncepcionais Orais , Relações Interpessoais , Satisfação Pessoal , Parceiros Sexuais , Anticoncepcionais Orais/administração & dosagem , Feminino , Clínicas de Fertilização , Humanos , Masculino , Gravidez , Parceiros Sexuais/psicologia
8.
Sci Rep ; 11(1): 21960, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34753960

RESUMO

Human populations, especially European, are polymorphic in the RHD gene. A significant fraction of their members carry no copy of the coding section of RHD gene, which results in their Rh-negative blood type. Theoretically, this polymorphism should be unstable. Carriers of the less frequent allele are penalized by reduced fertility because of the immunization of RhD-negative mothers by their RhD-positive babies, which results in hemolytic disease of the fetus and newborn in their subsequent progeny. For about 90 years, some form of balancing selection has been suspected to sustain this polymorphism. Several recent studies showed that the RhD-positive heterozygotes express higher viability than both types of homozygotes. However, the genotype of subjects in these studies was estimated only by indirect methods. Here we compared the physical and mental health of 178 women and 86 men who were directly tested for their RHD genotype. The results showed that RhD-positive homozygotic women had worse and RhD-positive homozygotic men better physical health than RhD-negative homozygotes; the difference between RhD-negative homozygotes and heterozygotes was not significant. Our results confirmed that health of RhD-positive heterozygotes and homozygotes differ. Therefore, any result of the comparison of subjects with RhD-positive and RhD-negative phenotype depends on the heterozygote-to-homozygote ratio in the RhD-positive sample. It is, therefore, crucial to analyze the effects of RHD-genotypes, not phenotypes in future studies.


Assuntos
Genótipo , Heterozigoto , Saúde Mental , Sistema do Grupo Sanguíneo Rh-Hr/genética , Fatores Sexuais , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
9.
Pathogens ; 10(8)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34451515

RESUMO

Latent infection of the globally spread parasite Toxoplasma gondii in humans has been associated with changes in personality and behavior. Numerous studies have investigated the effect of toxoplasmosis on depression, but their results are inconsistent. Our study focused on the effect of latent toxoplasmosis on depression in men and women in association with their fertility. In 2016-2018, we recruited clients (677 men and 664 women) of the Center for Assisted Reproduction and asked them to complete a standardized Beck Depression Inventory-II. In women without fertility problems, we found higher depression scores in Toxoplasma-positive than in Toxoplasma-negative (p = 0.010, Cohen's d = 0.48). Toxoplasma-positive infertile men, on the other hand, had lower depression scores than Toxoplasma-negative infertile men (p ≤ 0.001, Cohen's d = 0.48). Our results are consistent with the previously described effects of latent toxoplasmosis, which seem to go in opposite directions regarding the effect on personality and behavior of men and women. Our results could be explained by gender-contrasting reactions to chronic stress associated with lifelong infection. This suggests that due to gender differences in the impact of latent toxoplasmosis, future studies ought to perform separate analyses for women and men.

10.
Folia Parasitol (Praha) ; 682021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33762474

RESUMO

Numerous recent studies show that vitamin D deficiency potentiates various chronic physical and psychiatric disorders and diseases. It has been shown that a similar range of disorders is also associated with latent infection with Toxoplasma gondii (Nicolle et Manceaux, 1908). For instance, among cancer, diabetes and schizophrenia patients, we find a higher prevalence of both toxoplasmosis and vitamin D deficiency. Theoretically, therefore, vitamin D deficiency could be the missing link between toxoplasmosis and these disorders. We tested this hypothesis by searching for decreased vitamin D levels in the serum of subjects infected with T. gondii (furthermore called Toxoplasma-infected subjects) in two cross-sectional and one case-control study. Results of the first cross-sectional study (N = 72) suggest that Toxoplasma-infected neurasthenic patients have non-significantly lower levels of calcidiol than Toxoplasma-free patients (study A: P = 0.26 in women, P = 0.68 in men). However, two other studies (study B: N = 400; study C: N = 191) showed a non-significantly higher concentration of vitamin D in Toxoplasma-infected subjects than in Toxoplasma-free subjects both in men (study B: P = 0.70, study C: P = 0.55) and in women (study B: P = 0.64, study C: P = 0.12). Taken together, our preliminary results thus do not support the hypothesis that toxoplasmosis could be associated with vitamin D decrease.


Assuntos
Toxoplasmose/complicações , Deficiência de Vitaminas do Complexo B/etiologia , Vitamina D/sangue , Adulto , Calcifediol/sangue , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Infecção Latente/complicações , Masculino , Transtornos Mentais/complicações , Pessoa de Meia-Idade , Esquizofrenia/complicações , Toxoplasma
11.
Andrology ; 9(3): 854-862, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33420759

RESUMO

BACKGROUND: About a third of people in the world are infected with Toxoplasma gondii. This parasite has been found in the reproductive organs and semen of males of many animal species as well as humans. The effects of toxoplasmosis on sperm count, motility and morphology were confirmed in rats. A higher prevalence of toxoplasmosis has been observed in infertile men. On the other hand, no significant effect of infection on semen parameters in men was found in one already published study. OBJECTIVES: To compare the prevalence of toxoplasmosis in men with and without semen pathology and to examine in detail the possible impact of infection on semen volume, sperm count, motility and morphology. MATERIALS AND METHODS: The pre-registered cross-sectional study included 669 men who visited the Centre for Assisted Reproduction in Prague from June 2016 until June 2018. RESULTS: The incidence of fertility problems was significantly higher in the 163 Toxoplasma-infected men (48.47%) than in the 506 Toxoplasma-free men (42.29%), τ = 0.049, P = 0.029. After correction for multiple tests, we found significantly lower sperm concentration, concentration of progressively motile sperm, and concentration of non-progressively motile sperm in Toxoplasma-positive men than in Toxoplasma-negative men using partial Kendall correlation with age controlled. In addition, toxoplasmosis correlated with sperm quality in smokers but not in non-smokers. DISCUSSION AND CONCLUSION: Our results suggest that latent toxoplasmosis affects certain semen parameters (sperm count and motility), but does not seem to affect sperm morphology and semen volume. Impairment of semen parameters may be either a side effect of the presence of Toxoplasma gondii in male reproductive organs or a product of manipulation activity of the parasite aimed to increase the efficiency of the sexual route of its transmission. Tobacco smoking also appears to exacerbate the negative impact of toxoplasmosis on semen parameters.


Assuntos
Fertilidade , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Toxoplasmose/fisiopatologia , Adulto , Estudos Transversais , Humanos , Masculino , Estudos Prospectivos
12.
Am J Epidemiol ; 190(3): 386-392, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32929444

RESUMO

Toxoplasmosis is one of the most widespread human parasitoses in developed countries. Sexual transmission has been confirmed in several animal species, and indirect evidence suggests it may occur in humans. We compared the seropositivity to Toxoplasma gondii in couples who visited the Center for Assisted Reproduction in Prague from June 2016 to June 2018 and analyzed various risk factors including the serological status of sexual partner. By comparing the risk factors in men and women, we tested the hypothesis of male-to-female sexual transmission of toxoplasmosis. The prevalence of toxoplasmosis in women with infected male partners (25.6%; n = 156) was higher than in women with uninfected male partners (18.2%; n = 477; P = 0.045). Therefore, a partner's seropositivity seems to be a risk factor for infection in women (n = 593; prevalence ratio = 1.418; P = 0.045) but not in men (n = 573; prevalence ratio = 1.058; P = 0.816). Our results support the hypothesis of the sexual transmission of T. gondii from men to women. The risk may seem relatively low, but transmission can occur during unprotected sexual intercourse, which may be at the time of conception. Because of the risk of congenital toxoplasmosis, a lower risk of infection than that observed in our study can represent a serious health problem.


Assuntos
Parceiros Sexuais , Toxoplasmose/epidemiologia , Toxoplasmose/transmissão , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco
13.
Exp Dermatol ; 29(7): 598-609, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32478926

RESUMO

About 1-2% of European population are redheaded, meaning they synthesize more pheomelanin than eumelanin, the main melanin pigment in humans. Several mutations could be responsible for this phenotype. It has been suggested that corresponding mutations spread in Europe due to a founder effect shaped either by a relaxation of selection for dark, UV-protective phenotypes or by sexual selection in favour of rare phenotypes. In our study, we investigated the levels of vitamin D precursor 25(OH)D3 (calcidiol) and folic acid in the blood serum of 73 redheaded and 130 non-redheaded individuals. In redheaded individuals, we found higher 25(OH)D3 concentrations and approximately the same folic acid concentrations as in non-redheaded subjects. 25(OH)D3 concentrations correlated with the intensity of hair redness measured by two spectrophotometric methods and estimated by participants themselves and by independent observers. In non-redheaded individuals, 25(OH)D3 levels covaried with the amount of sun exposure and intensity of suntan while in redheaded individuals, this was not the case. It suggests that increased 25(OH)D3 levels in redheaded individuals are due to differences in physiology rather than in behaviour. We also found that folic acid levels increased with age and the intensity of baldness and decreased with the frequency of visiting tanning salons. Our results suggest that the redheaded phenotype could be an evolutionary adaptation for sufficient photosynthesis of provitamin D in conditions of low intensity of UVB radiation in central and northern parts of Europe.


Assuntos
Adaptação Fisiológica , Calcifediol/sangue , Ácido Fólico/sangue , Cor de Cabelo/fisiologia , Pigmentação da Pele/fisiologia , Adulto , Envelhecimento/sangue , Alopecia/sangue , Estudos de Casos e Controles , Clima , Evolução Molecular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Luz Solar , Bronzeado/fisiologia
14.
Viruses ; 11(4)2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970559

RESUMO

Background: Massilia virus (MASV) is a phlebovirus isolated from Phlebotomus perniciosus in various regions of southwestern Europe. It is closely related to human pathogens such as Toscana virus and sandfly fever Naples virus. The natural cycle of phleboviruses is poorly understood. Indeed, experimental studies demonstrate that transovarial and sexual transmission are not efficient enough for the maintenance of the virus in nature and to date there is no convincing evidence that a species of vertebrates is the reservoir of the virus. Here, we studied various transmission routes of MASV taking advantage of experimental colonies representing different species of sand flies. Methodology/Principal findings: In P. perniciosus, four sources of infection were compared: (i) Virus-seeded larval food to the first instar larvae (L1), or (ii) to the fourth instar larvae (L4), (iii) virus-seeded blood meal to adult females, and (iv) virus-seeded sugar meal to adults of both sexes. From 875 adults emerged from infected L1 and L4, only three were positive. In females infected by bloodmeal the infection rate was high before defecation, then it decreased drastically; MASV RNA was detected in only 5 out of 27 post-defecation. Surprisingly, the most efficient route of infection was observed after intake of virus-seeded sugar meal: 72% of females (79/110) and 52% of males (51/99) were found to be MASV RNA-positive. In addition, MASV-infected sandflies regurgitated virus particules into the sugar drop and MASV RNA was detectable in this drop for at least 24 h after regurgitation. MASV RNA was detected in about one third of the P. perniciosus exposed to this sugar drop contaminated by regurgitation. Sugar meal infection was also tested with six other species of sand flies. In males, there were no significant differences in infection rates when compared to P. perniciosus. In females, most species tested showed high infection rate at the beginning but then significant gradual decrease in infection rate during the experiment. Conclusions/Significance: We present the first description of arboviral infection of a dipteran vector using sugar meal. In all seven sand fly species tested, MASV was detected for two weeks post-infection. Our results showed that MASV can be transmitted between P. perniciosus either through co-feeding or via an infected sugar source such as plant sap. These newly described routes of horizontal transmission may play an important role in the circulation of phleboviruses in nature.


Assuntos
Comportamento Alimentar , Contaminação de Alimentos , Insetos Vetores/virologia , Febre por Flebótomos/transmissão , Phlebovirus/isolamento & purificação , Psychodidae/virologia , Animais , Fômites/virologia , Insetos Vetores/fisiologia , Refeições , Phlebovirus/crescimento & desenvolvimento , Psychodidae/fisiologia , Açúcares
15.
PLoS One ; 13(12): e0209773, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30589911

RESUMO

BACKGROUNDS: The prevalence of toxoplasmosis is higher in schizophrenics than in the general population. It has been suggested that certain symptoms of schizophrenia, including changes in olfactory functions, are in fact symptoms of toxoplasmosis that can be easily detected in schizophrenics only due to the increased prevalence of toxoplasmosis in this population. Schizophrenics have impaired identification of odors and lower sensitivity of odor detection, however, no information about these parameters of non-schizophrenic Toxoplasma-infected subjects is available. METHODS: Here we searched for differences in olfactory functions between 62 infected and 61 noninfected non-schizophrenic subjects using the case-controls experimental design. RESULTS: The infected men scored better than the non-infected controls in the standard odor-identification test. The infected women rated all smells as more intensive while the infected men rated nearly all smells as less intensive. Infected women rated the pleasantness of the smell of the cat urine as higher than the non-infected women and the opposite was true for the men-in contrast, higher pleasantness of odor in infected men and lower in infected women were observed and described in the 2011 study. Toxoplasmosis, Rh, and toxoplasmosis-Rh interaction were not associated with the rated pleasantness of the smell of other stimuli. However, our sample contained only 17 Rh negative men and 30 Rh negative women. Therefore, all results concerning the main effects of Rh factor and the interaction with Rh factor must be considered only preliminary. CONCLUSIONS: Our results suggest that latent toxoplasmosis is associated with changes in the olfactory functions in humans; however, the observed changes differ from those observed in schizophrenics.


Assuntos
Esquizofrenia/fisiopatologia , Esquizofrenia/parasitologia , Toxoplasmose/fisiopatologia , Adulto , Animais , Estudos de Casos e Controles , Gatos , Feminino , Humanos , Masculino , Odorantes , Sistema do Grupo Sanguíneo Rh-Hr/metabolismo , Esquizofrenia/metabolismo , Toxoplasma/patogenicidade , Toxoplasmose/metabolismo , Urina , Adulto Jovem
16.
Mem Inst Oswaldo Cruz ; 113(5): e170333, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29513819

RESUMO

BACKGROUND Leishmania major is an Old World species causing cutaneous leishmaniasis and is transmitted by Phlebotomus papatasi and Phlebotomus duboscqi. In Brazil, two isolates from patients who never left the country were characterised as L. major-like (BH49 and BH121). Using molecular techniques, these isolates were indistinguishable from the L. major reference strain (FV1). OBJECTIVES We evaluated the lipophosphoglycans (LPGs) of the strains and their behaviour in Old and New World sand fly vectors. METHODS LPGs were purified, and repeat units were qualitatively evaluated by immunoblotting. Experimental in vivo infection with L. major-like strains was performed in Lutzomyia longipalpis (New World, permissive vector) and Ph. papatasi (Old World, restrictive or specific vector). FINDINGS The LPGs of both strains were devoid of arabinosylated side chains, whereas the LPG of strain BH49 was more galactosylated than that of strain BH121. All strains with different levels of galactosylation in their LPGs were able to infect both vectors, exhibiting colonisation of the stomodeal valve and metacyclogenesis. The BH121 strain (less galactosylated) exhibited lower infection intensity compared to BH49 and FV1 in both vectors. MAIN CONCLUSIONS Intraspecific variation in the LPG of L. major-like strains occur, and the different galactosylation levels affected interactions with the invertebrate host.


Assuntos
Galactose/metabolismo , Glicoesfingolipídeos/metabolismo , Insetos Vetores/fisiologia , Leishmania major/fisiologia , Phlebotomus/parasitologia , Psychodidae/parasitologia , Animais , Glicoesfingolipídeos/química , Interações Hospedeiro-Patógeno , Insetos Vetores/química , Leishmania major/química , Especificidade da Espécie
17.
PLoS One ; 13(2): e0192723, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29438445

RESUMO

Leishmania parasites cause human cutaneous, mucocutaneous and visceral leishmaniasis. Several studies proposed involvement of certain genes in infectivity of these parasites based on differential mRNA expression data. Due to unusual gene expression mechanism, functions of such genes must be further validated experimentally. Here, we investigated a role of one of the putative virulence factors, LmxM.22.0010-encoded BTN1 (a protein involved in Batten disease in humans), in L. mexicana infectivity. Due to the incredible plasticity of the L. mexicana genome, we failed to obtain a complete knock-out of LmxM.22.0010 using conventional recombination-based approach even after ablating four alleles of this gene. To overcome this, we established a modified CRISPR-Cas9 system with genomic expression of Cas9 nuclease and gRNA. Application of this system allowed us to establish a complete BTN1 KO strain of L. mexicana. The mutant strain did not show any difference in growth kinetics and differentiation in vitro, as well as in the infectivity for insect vectors and mice hosts. Based on the whole-transcriptome profiling, LmxM.22.0010-encoded BTN1 was considered a putative factor of virulence in Leishmania. Our study suggests that ablation of LmxM.22.0010 does not influence L. mexicana infectivity and further illustrates importance of experimental validation of in silico-predicted virulence factors. Here we also describe the whole genome sequencing of the widely used model isolate L. mexicana M379 and report a modified CRISPR/Cas9 system suitable for complete KO of multi-copy genes in organisms with flexible genomes.


Assuntos
Sistemas CRISPR-Cas , Genes de Protozoários , Leishmania mexicana/genética , Leishmania mexicana/patogenicidade , Animais , Simulação por Computador , Feminino , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes/métodos , Humanos , Insetos Vetores/parasitologia , Leishmaniose Cutânea/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Psychodidae/parasitologia , Virulência/genética
18.
Mult Scler Relat Disord ; 19: 153-160, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29241142

RESUMO

BACKGROUND: Patient engagement is vital in multiple sclerosis (MS) in order to optimise outcomes for patients, society and healthcare systems. It is essential to involve all stakeholders in potential solutions, working in a multidisciplinary way to ensure that people with MS (PwMS) are included in shared decision-making and disease management. To start this process, a collaborative, open environment between PwMS and healthcare professionals (HCPs) is required so that similarities and disparities in the perception of key areas in patient care and unmet needs can be identified. With this patient-centred approach in mind, in 2016 the MS in the 21st Century Steering Group formed a unique collaboration to include PwMS in the Steering Group to provide a platform for the patient voice. METHODS: The MS in the 21st Century initiative set out to foster engagement through a series of open-forum joint workshops. The aims of these workshops were: to identify similarities and disparities in the perception and prioritisation in three key areas (unmet needs, the treatment burden in MS, and factors that impact patient engagement), and to provide practical advice on how the gaps in perception and understanding in these key areas could be bridged. RESULTS: Combined practical advice and direction are provided here as eight actions: 1. Improve communication to raise the quality of HCP-patient interaction and optimise the limited time available for consultations. 2. Heighten the awareness of 'hidden' disease symptoms and how these can be managed. 3. Improve the dialogue surrounding the benefit versus risk issues of therapies to help patients become fully informed and active participants in their healthcare decisions. 4. Provide accurate, lucid information in an easily accessible format from reliable sources. 5. Encourage HCPs and multidisciplinary teams to acquire and share new knowledge and information among their teams and with PwMS. 6. Foster greater understanding and awareness of challenges faced by PwMS and HCPs in treating MS. 7. Collaborate to develop local education, communication and patient-engagement initiatives. 8. Motivate PwMS to become advocates for self-management in MS care. CONCLUSION: Our study of PwMS and HCPs in the MS in the 21st Century initiative has highlighted eight practical actions. These actions identify how differences and gaps in unmet needs, treatment burden, and patient engagement between PwMS and HCPs can be bridged to improve MS disease management. Of particular interest now are patient-centred educational resources that can be used during time-limited consultations to enhance understanding of disease and improve communication. Actively bridging these gaps in a joint approach enables PwMS to take part in shared decision-making; with improved communication and reliable information, patients can make informed decisions with their HCPs, as part of their own personalised disease management.


Assuntos
Efeitos Psicossociais da Doença , Tomada de Decisões , Gerenciamento Clínico , Educação , Esclerose Múltipla/terapia , Determinação de Necessidades de Cuidados de Saúde , Educação de Pacientes como Assunto , Participação do Paciente , Relações Profissional-Paciente , Adulto , Humanos
19.
Mem. Inst. Oswaldo Cruz ; 113(5): e170333, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-894920

RESUMO

BACKGROUND Leishmania major is an Old World species causing cutaneous leishmaniasis and is transmitted by Phlebotomus papatasi and Phlebotomus duboscqi. In Brazil, two isolates from patients who never left the country were characterised as L. major-like (BH49 and BH121). Using molecular techniques, these isolates were indistinguishable from the L. major reference strain (FV1). OBJECTIVES We evaluated the lipophosphoglycans (LPGs) of the strains and their behaviour in Old and New World sand fly vectors. METHODS LPGs were purified, and repeat units were qualitatively evaluated by immunoblotting. Experimental in vivo infection with L. major-like strains was performed in Lutzomyia longipalpis (New World, permissive vector) and Ph. papatasi (Old World, restrictive or specific vector). FINDINGS The LPGs of both strains were devoid of arabinosylated side chains, whereas the LPG of strain BH49 was more galactosylated than that of strain BH121. All strains with different levels of galactosylation in their LPGs were able to infect both vectors, exhibiting colonisation of the stomodeal valve and metacyclogenesis. The BH121 strain (less galactosylated) exhibited lower infection intensity compared to BH49 and FV1 in both vectors. MAIN CONCLUSIONS Intraspecific variation in the LPG of L. major-like strains occur, and the different galactosylation levels affected interactions with the invertebrate host.


Assuntos
Humanos , Leishmania major , Glicoproteínas de Membrana Associadas ao Lisossomo , Psychodidae , Interações Hospedeiro-Parasita
20.
PLoS Negl Trop Dis ; 11(7): e0005782, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28742133

RESUMO

BACKGROUND: Leishmania virulence factors responsible for the complicated epidemiology of the various leishmaniases remain mainly unidentified. This study is a characterization of a gene previously identified as upregulated in two of three overlapping datasets containing putative factors important for Leishmania's ability to establish mammalian intracellular infection and to colonize the gut of an insect vector. METHODOLOGY/PRINCIPAL FINDINGS: The investigated gene encodes ATP/GTP binding motif-containing protein related to Leishmania development 1 (ALD1), a cytosolic protein that contains a cryptic ATP/GTP binding P-loop. We compared differentiation, growth rates, and infective abilities of wild-type and ALD1 null mutant cell lines of L. mexicana. Loss of ALD1 results in retarded growth kinetics but not defects in differentiation in axenic culture. Similarly, when mice and the sand fly vector were infected with the ALD1 null mutant, the primary difference in infection and colonization phenotype relative to wild type was an inability to achieve maximal host pathogenicity. While ability of the ALD1 null mutant cells to infect macrophages in vitro was not affected, replication within macrophages was clearly curtailed. CONCLUSIONS/SIGNIFICANCE: L. mexicana ALD1, encoding a protein with no assigned functional domains or motifs, was identified utilizing multiple comparative analyses with the related and often experimentally overlooked monoxenous flagellates. We found that it plays a role in Leishmania infection and colonization in vitro and in vivo. Results suggest that ALD1 functions in L. mexicana's general metabolic network, rather than function in specific aspect of virulence as anticipated from the compared datasets. This result validates our comparative genomics approach for finding relevant factors, yet highlights the importance of quality laboratory-based analysis of genes tagged by these methods.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Leishmania mexicana/patogenicidade , Macrófagos/parasitologia , Proteínas de Protozoários/metabolismo , Psychodidae/parasitologia , Animais , Feminino , Proteínas de Ligação ao GTP/genética , Regulação da Expressão Gênica no Desenvolvimento , Insetos Vetores/parasitologia , Leishmania mexicana/genética , Leishmaniose Cutânea/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Protozoários/genética , Virulência
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