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1.
Curr Gastroenterol Rep ; 26(1): 1-8, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38180722

RESUMEN

PURPOSE OF REVIEW: Inflammatory Bowel Disease (IBD) is a chronic GI inflammatory condition induced by a dysregulated immune system activation, whereas HIV infection causes depletion of the immune system, inducing immunosuppression. Given the increasing incidence of IBD across the globe, including in developing countries, the co-prevalence of both conditions is expected to increase. Herein, we systematically review the data describing disease course when both pathologies co-exist. RECENT FINDINGS: Overall, the co-prevalence of IBD and HIV is around 0.1 to 2%. While IBD does not seem to affect HIV course, the opposite is controversial, as some studies report milder IBD phenotype, with fewer disease relapses especially when CD4 + counts are lower than 200 cells/µL. Despite growing evidence to support the safety of the use of immunosuppressants and biologics in IBD-HIV infected patients, these classes of drugs are used in less than 50% of patients, as compared to non-HIV infected IBD patients. There is a need for more studies on disease course and safety of IBD medications in the setting of IBD.


Asunto(s)
Colitis Ulcerosa , Infecciones por VIH , Enfermedades Inflamatorias del Intestino , Humanos , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Inmunosupresores/efectos adversos , Terapia de Inmunosupresión , Colitis Ulcerosa/complicaciones
2.
Clin Infect Dis ; 77(5): 740-748, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37288954

RESUMEN

BACKGROUND: Integrase strand transfer inhibitor-based regimens are recommended for first-line therapy in human immunodeficiency virus type 2 (HIV-2). Nonetheless, dolutegravir (DTG) clinical trial data are lacking. METHODS: We conducted a phase 2, single-arm, open-label trial to evaluate the safety and efficacy of a triple therapy regimen that included DTG in persons with HIV-2 (PWHIV-2) in Portugal. Treatment-naive adults receive DTG in combination with 2 nucleoside reverse transcriptase inhibitors (NRTIs). Treatment efficacy was evaluated by the proportion of patients who achieved a plasma viral load (pVL) <40 copies/mL and/or by the change from baseline in CD4+ T-cell count and in CD4/CD8 ratio at week 48. RESULTS: A total of 30 patients were enrolled (22 women; median age, 55 years). At baseline, 17 (56.7%) individuals were viremic (median, pVL 190 copies/mL; interquartile range [IQR], 99-445). The median CD4 count was 438 cells/µL (IQR, 335-605), and the CD4/CD8 ratio was 0.8. Three patients discontinued the study. At week 48, all participants (27) had pVL <40 copies/mL. No virological failures were observed. Mean changes in CD4 count and CD4/CD8 ratio at week 48 were 95.59 cells/µL (95% confidence interval [CI], 28-163) and 0.32 (95% CI, .19 to .46). The most common drug-related adverse events were headache and nausea. One participant discontinued due to central nervous system symptoms. No serious adverse events were reported. CONCLUSIONS: DTG plus 2 NRTIs is safe and effective as first-line treatment for PWHIV-2 with a tolerability profile previously known. No virological failures were observed that suggest a high potency of DTG in HIV-2 as occurs in HIV-1. CLINICAL TRIALS REGISTRATION: M NCT03224338.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Adulto , Femenino , Humanos , Persona de Mediana Edad , Fármacos Anti-VIH/efectos adversos , Compuestos Heterocíclicos con 3 Anillos/efectos adversos , Infecciones por VIH/tratamiento farmacológico , VIH-2 , Inhibidores de la Transcriptasa Inversa/efectos adversos , Resultado del Tratamiento , Carga Viral , Masculino
3.
Mol Biol Evol ; 38(3): 805-818, 2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-32926156

RESUMEN

About 15,000 angiosperm species (∼6%) have separate sexes, a phenomenon known as dioecy. Why dioecious taxa are so rare is still an open question. Early work reported lower species richness in dioecious compared with nondioecious sister clades, raising the hypothesis that dioecy may be an evolutionary dead-end. This hypothesis has been recently challenged by macroevolutionary analyses that detected no or even positive effect of dioecy on diversification. However, the possible genetic consequences of dioecy at the population level, which could drive the long-term fate of dioecious lineages, have not been tested so far. Here, we used a population genomics approach in the Silene genus to look for possible effects of dioecy, especially for potential evidence of evolutionary handicaps of dioecy underlying the dead-end hypothesis. We collected individual-based RNA-seq data from several populations in 13 closely related species with different sexual systems: seven dioecious, three hermaphroditic, and three gynodioecious species. We show that dioecy is associated with increased genetic diversity, as well as higher selection efficacy both against deleterious mutations and for beneficial mutations. The results hold after controlling for phylogenetic inertia, differences in species census population sizes and geographic ranges. We conclude that dioecious Silene species neither show signs of increased mutational load nor genetic evidence for extinction risk. We discuss these observations in the light of the possible demographic differences between dioecious and self-compatible hermaphroditic species and how this could be related to alternatives to the dead-end hypothesis to explain the rarity of dioecy.


Asunto(s)
Adaptación Biológica , Evolución Biológica , Variación Genética , Selección Genética , Silene/genética , Flores/anatomía & histología , Reproducción/genética , Silene/anatomía & histología
4.
Support Care Cancer ; 30(3): 2723-2734, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34822003

RESUMEN

PURPOSE: This study aimed to evaluate the effects and mechanisms of action of royal jelly (RJ) and propolis compared to photobiomodulation therapy (PBMT) in an animal model of 5-fluorouracil-related oral mucositis (OM). METHODS: Seventy-two male Wistar rats were randomly allocated to four groups (n = 18 each): control (no treatment), PBMT (intraoral laser, 6 J/cm2), RJ, and propolis. On days 0 and 2, the animals received an injection of 5-fluorouracil (5-FU). The buccal mucosa was scratched (days 3 and 4) and the treatments were initiated on day 5. Six animals of each group were euthanized on days 8, 10, and 14. Phytochemical analysis (thin-layer chromatography, TLC) and clinical, histopathological, and immunohistochemical analysis of pS6, pAKT, and NF-κB were performed, and oxidative stress markers were also investigated. RESULTS: TLC revealed the presence of large amounts of sucrose (Rf 0.34) in RJ and of flavonoids in propolis. Lower clinical OM scores were observed on day 8, and improved morphological data were observed on day 10 in the PBMT, RJ, and propolis groups (p < 0.05). On day 8, immunoexpression of pS6, pAKT, and NF-κB was increased compared to control. On day 14, reduced glutathione (GSH) antioxidant levels were increased in the propolis group compared to control (p < 0.05). CONCLUSIONS: Our results showed that RJ and propolis, as well as PBMT, are effective in the treatment of OM. Considering that some patients who develop OM do not have access to PBMT, the present study demonstrated that topical application of RJ and propolis may be an important alternative for the treatment of OM.


Asunto(s)
Terapia por Luz de Baja Intensidad , Própolis , Estomatitis , Animales , Ácidos Grasos , Fluorouracilo , Humanos , Masculino , Ratas , Ratas Wistar , Estomatitis/inducido químicamente , Estomatitis/terapia
5.
Microb Pathog ; 125: 295-305, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30267894

RESUMEN

Macrophages play an important role in the generation of host immune responses against H. pylori. In this study, we investigated the effect of a functionally uncharacterized H. pylori secreted protein HP1173 on macrophage responses. In a screen of eight H. pylori strains, similar expression levels of the HP1173 protein were observed in the whole-cell extracts, however; the amount of protein released into the culture medium varied significantly among strains. Recombinant purified HP1173 (rHP1173) was found to bind to THP-1 cells that were differentiated into macrophages via phorbol-12-myristate-13-acetate (PMA) treatment. The exposure of macrophages to rHP1173 led to the production of the proinflammatory cytokines TNF and IL-1ß and the chemokine CXCL8 in a dose- and time-dependent manner. Under similar conditions, rHP1173 failed to induce apoptosis in macrophages. Furthermore, rHP1173-induced expression of TNF, IL-1ß and CXCL8 was observed at the level of gene transcription. Incubation of macrophages in the conditioned medium from a mutant H. pylori strain 26695 lacking HP1173 protein expression resulted in the reduced induction of TNF, CXCL8 and IL-1ß, confirming the role of the endogenous protein. Intracellular signaling involving MAPKs, NF-κB and the AP-1 family of transcription factors was required for rHP1173-induced TNF, CXCL8 and IL-1ß release from macrophages. The blocking of MyD88, which is an adaptor for multiple toll-like receptors (TLRs), had no effect on rHP1173-induced TNF, CXCL8 and IL-1ß release from macrophages, suggesting that Myd88-dependent TLR signaling was not involved in the recognition of and responses to rHP1173. These findings provide novel insights into the potential role of HP1173 in H. pylori infection-associated disease development.


Asunto(s)
Proteínas Bacterianas/metabolismo , Citocinas/biosíntesis , Helicobacter pylori/inmunología , Interacciones Huésped-Patógeno , Macrófagos/inmunología , Transducción de Señal , Proteínas Bacterianas/genética , Medios de Cultivo Condicionados , Perfilación de la Expresión Génica , Helicobacter pylori/genética , Humanos , Macrófagos/microbiología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Unión Proteica , Células THP-1 , Factor de Transcripción AP-1/metabolismo
6.
PLoS Genet ; 11(10): e1005536, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26448481

RESUMEN

Sexual dimorphism, including differences in morphology, behavior and physiology between females and males, is widespread in animals and plants and is shaped by gene expression differences between the sexes. Such expression differences may also underlie sex-specific responses of hosts to pathogen infections, most notably when pathogens induce partial sex reversal in infected hosts. The genetic changes associated with sex-specific responses to pathogen infections on the one hand, and sexual dimorphism on the other hand, remain poorly understood. The dioecious White Campion (Silene latifolia) displays sexual dimorphism in floral traits and infection with the smut fungus Micobrotryum lychnidis-dioicae induces a partial sex reversal in females. We find strong sex-specific responses to pathogen infection and reduced sexual dimorphism in infected S. latifolia. This provides a direct link between pathogen-mediated changes in sex-biased gene expression and altered sexual dimorphism in the host. Expression changes following infection affected mainly genes with male-biased expression in healthy plants. In females, these genes were up-regulated, leading to a masculinization of the transcriptome. In contrast, infection in males was associated with down-regulation of these genes, leading to a demasculinization of the transcriptome. To a lesser extent, genes with female-biased expression in healthy plants were also affected in opposite directions in the two sexes. These genes were overall down-regulated in females and up-regulated in males, causing, respectively, a defeminization in infected females and a feminization of the transcriptome in infected males. Our results reveal strong sex-specific responses to pathogen infection in a dioecious plant and provide a link between pathogen-induced changes in sex-biased gene expression and sexual dimorphism.


Asunto(s)
Enfermedades de las Plantas/genética , Silene/genética , Transcripción Genética , Basidiomycota/genética , Basidiomycota/patogenicidad , Regulación del Desarrollo de la Expresión Génica , Fenotipo , Enfermedades de las Plantas/microbiología , Selección Genética , Caracteres Sexuales , Silene/crecimiento & desarrollo , Transcriptoma/genética
7.
J Exp Bot ; 67(9): 2549-63, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27006484

RESUMEN

We provide an overview of methods and workflows that can be used to investigate the topologies of Gene Regulatory Networks (GRNs) in the context of plant evolutionary-developmental (evo-devo) biology. Many of the species that occupy key positions in plant phylogeny are poorly adapted as laboratory models and so we focus here on techniques that can be efficiently applied to both model and non-model species of interest to plant evo-devo. We outline methods that can be used to describe gene expression patterns and also to elucidate the transcriptional, post-transcriptional, and epigenetic regulatory mechanisms underlying these patterns, in any plant species with a sequenced genome. We furthermore describe how the technique of Protein Resurrection can be used to confirm inferences on ancestral GRNs and also to provide otherwise-inaccessible points of reference in evolutionary histories by exploiting paralogues generated in gene and whole genome duplication events. Finally, we argue for the better integration of molecular data with information from paleobotanical, paleoecological, and paleogeographical studies to provide the fullest possible picture of the processes that have shaped the evolution of plant development.


Asunto(s)
Redes Reguladoras de Genes/fisiología , Desarrollo de la Planta/genética , Evolución Biológica , Redes Reguladoras de Genes/genética , Plantas/genética
8.
Cell Microbiol ; 15(11): 1938-54, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23834289

RESUMEN

Antimicrobial peptides (AMPs) constitute an essential part of the innate immune defence. Pathogenic bacteria have evolved numerous strategies to withstand AMP-mediated killing. The influence of host epithelia on bacterial AMP resistance is, however, still largely unknown. We found that adhesion to pharyngeal epithelial cells protected Neisseria meningitidis, a leading cause of meningitis and sepsis, from the human cathelicidin LL-37, the cationic model amphipathic peptide (MAP) and the peptaibol alamethicin, but not from polymyxin B. Adhesion to primary airway epithelia resulted in a similar increase in LL-37 resistance. The inhibition of selective host cell signalling mediated by RhoA and Cdc42 was found to abolish the adhesion-induced LL-37 resistance by a mechanism unrelated to the actin cytoskeleton. Moreover, N. meningitidis triggered the formation of cholesterol-rich membrane microdomains in pharyngeal epithelial cells, and host cell cholesterol proved to be essential for adhesion-induced resistance. Our data highlight the importance of Rho GTPase-dependent host cell signalling for meningococcal AMP resistance. These results indicate that N. meningitidis selectively exploits the epithelial microenvironment in order to protect itself from LL-37.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/metabolismo , Adhesión Bacteriana , Farmacorresistencia Bacteriana , Células Epiteliales/microbiología , Neisseria meningitidis/efectos de los fármacos , Proteína de Unión al GTP cdc42/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Alameticina/metabolismo , Células Cultivadas , Células Epiteliales/metabolismo , Humanos , Microdominios de Membrana/metabolismo , Neisseria meningitidis/fisiología , Catelicidinas
9.
Cureus ; 16(1): e52090, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38344590

RESUMEN

Tuberculosis (TB), a Mycobacterium tuberculosis (Mtb) infection, remains a significant global health concern despite a declining incidence. This report highlights a complex case involving a 24-year-old patient from Angola who presented with a constellation of symptoms, including fever, weight loss, and neurological deficits. The patient had been on chronic corticosteroid therapy, a known risk factor for the reactivation of latent TB infection (LTBI). Her clinical course was marked by diagnostic challenges, such as a previous diagnosis of Kikuchi's disease and paradoxical progression despite appropriate tuberculostatic chemotherapy. Miliary TB, characterized by widespread dissemination of Mtb from the primary site of infection, can manifest in various extrapulmonary locations. Central nervous system (CNS) involvement, particularly TB meningitis, is the most severe form of TB, associated with significant morbidity and mortality. The diagnosis of miliary and CNS TB can be elusive due to nonspecific clinical presentations and imaging findings. This case underscores the importance of a high index of suspicion, especially in immunocompromised individuals, and the need for comprehensive microbiological analysis, including cerebrospinal fluid (CSF) examination, to confirm CNS involvement. Furthermore, this case illustrates the challenges associated with TB treatment, including the risk of drug toxicity, medication adherence, and the potential for drug resistance. Treatment duration for miliary TB is extended, typically lasting nine months to a year, and may require adaptation based on the patient's clinical response and drug penetration into the CNS. Corticosteroids play a critical role as adjuvant therapy, particularly in cases with perilesional edema or paradoxical reactions during treatment. This case underscores the complexity of diagnosing and managing miliary and CNS TB, emphasizing the importance of considering TB as a diagnostic possibility in patients with nonspecific symptoms and risk factors. Early identification, multidisciplinary collaboration, and tailored therapeutic strategies are essential for achieving optimal outcomes in such challenging cases. Additionally, screening for latent TB infection should be a priority for patients requiring immunosuppressive therapy to mitigate the risk of reactivation.

10.
J Infect Public Health ; 17(5): 810-818, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38522155

RESUMEN

BACKGROUND: In Europe, up to 70% of visceral leishmaniasis (VL) cases occurring in adults living with HIV. People living with HIV with VL co-infection often display persistent parasitemia, requiring chronic intermittent anti-Leishmania therapies. Consequently, frequent VL relapses and higher mortality rates are common in these individuals. As such, it is of paramount importance to understand the reasons for parasite persistence to improve infection management. METHODS: To outline possible causes for treatment failure in the context of HIV-VL, we followed a person living with HIV-VL co-infection for nine years in a 12-month period. We characterized: HIV-related clinicopathological alterations (CD4+ T counts and viremia) and Leishmania-specific seroreactivity, parasitemia, quantification of pro-inflammatory cytokines upon stimulation and studied a Leishmania clinical isolate recovered during this period. RESULTS: The subject presented controlled viremia and low CD4+ counts. The subject remained PCR positive for Leishmania and also seropositive. The cellular response to parasite antigens was erratic. The isolate was identified as the first Leishmania infantum case with evidence of decreased miltefosine susceptibility in Portugal. CONCLUSION: Treatment failure is a multifactorial process driven by host and parasite determinants. Still, the real-time determination of drug susceptibility profiles in clinical isolates is an unexplored resource in the monitoring of VL.


Asunto(s)
Coinfección , Infecciones por VIH , Leishmania infantum , Leishmaniasis Visceral , Fosforilcolina/análogos & derivados , Adulto , Humanos , Portugal , Coinfección/tratamiento farmacológico , Parasitemia , Viremia , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Leishmaniasis Visceral/complicaciones , Leishmaniasis Visceral/tratamiento farmacológico
11.
Transplantation ; 108(1): 284-293, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37638863

RESUMEN

BACKGROUND: After kidney transplant, nonadherence to immunosuppressive therapy is the main cause of impaired kidney function and graft loss. The objective of this study was the development and internal validation of a clinical questionnaire for assessing the predisposition to adherence to immunosuppressive therapy in kidney pretransplant patients. METHODS: Multicenter prospective study conducted in 7 kidney hemodialysis and 6 kidney transplant centers of 3 Brazilian state capitals. Kidney transplant candidate patients of both sexes and >18-y-old were included. Retransplanted patients were excluded. A 72-item pilot version of the questionnaire, created through literature review complemented with a focus group of 8 kidney pretransplant patients, was administered to 541 kidney transplant candidate patients. Factor analysis with varimax rotation was used for questionnaire development. Internal validity evaluation used Cronbach's alpha and test-retest reliability. Construct validity was assessed by differentiation by known groups. RESULTS: The final questionnaire, named Kidney AlloTransplant Immunosuppressive Therapy Adherence (KATITA) Questionnaire, consisting of 25 items in 3 dimensions, presented good internal consistency reliability (Cronbach's alpha 0.81). The 3 dimensions and respective Cronbach's alpha were "Carelessness" (14 items, 0.81), "Skepticism" (6 items, 0.57), and "Concern" (5 items, 0.62). The interdimension correlation matrix showed low correlation coefficients (<0.35). Test-retest reliability, evaluated with 154 patients, showed an intraclass correlation coefficient of 0.62 (moderate agreement). The scale showed construct validity. CONCLUSIONS: The KATITA-25 questionnaire is the first psychometric instrument for evaluation of predisposition to nonadherence to immunosuppressive medication in candidate patients for kidney transplant in the pretransplant setting.


Asunto(s)
Trasplante de Riñón , Masculino , Femenino , Humanos , Reproducibilidad de los Resultados , Estudios Prospectivos , Trasplante de Riñón/efectos adversos , Inmunosupresores/efectos adversos , Encuestas y Cuestionarios , Psicometría/métodos , Susceptibilidad a Enfermedades , Riñón
12.
Transplantation ; 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38548683

RESUMEN

BACKGROUND: The self-administered Kidney AlloTransplant Immunosuppressive Therapy Adherence (KATITA-25) questionnaire is a multidimensional scale for use in the pretransplant setting that evaluates the predisposition to nonadherence of patients who are candidates to kidney transplant. The scale has shown adequate internal consistency and test-retest reliability. This study presents the results of an external validation study of the KATITA-25 scale. METHODS: Patients >18 y old scheduled for kidney transplant were included in this multicenter study. The KATITA-25 scale was administered before surgery and then at 3-mo posttransplantation for evaluation of scale sensitivity to change. At this time, 2 validated medication adherence scales were applied for assessment of concurrent validity. For evaluation of predictive validity, nonadherence to immunosuppressive medication was assessed at 6 and 12 mo after transplantation by 3 independent methods: patient self-report of nonadherence using the Morisky-Green-Levine Medication Assessment Questionnaire scale, serum trough levels of immunosuppressants, and pharmacy refills. RESULTS: Three twenty-two patients were available for evaluation of concurrent validity and 311 patients of predictive validity. After kidney transplant, the median KATITA-25 score decreased from 20 to 8 (P < 0.001), demonstrating scale sensitivity to change, and the KATITA-25 score showed correlation with the Basel Assessment of Adherence to Immunosuppressive Medication Scale score (Spearman's ρ 0.18, P = 0.002) and the Cuestionario para la Evaluación de la Adhesión al Tratamiento Antiretroviral scores (ρ -0.17, P = 0.002), confirming concurrent validity. The nonadherence rate was 57.6%. The scale predictive validity was demonstrated by the area under the receiver operating characteristics curve (0.68), sensitivity (59.8%), specificity (68.2%), and positive predictive value (71.8%). CONCLUSIONS: This external validation study of KATITA-25 scale provided evidence of sensitivity to change, and structural, criterion, and predictive validity.

13.
Front Public Health ; 12: 1336845, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500732

RESUMEN

Introduction: HIV late presentation (LP) remains excessive in Europe. We aimed to analyze the factors associated with late presentation in the MSM population newly diagnosed with HIV in Portugal between 2014 and 2019. Methods: We included 391 newly HIV-1 diagnosed Men who have Sex with Men (MSM), from the BESTHOPE project, in 17 countrywide Portuguese hospitals. The data included clinical and socio-behavioral questionnaires and the viral genomic sequence obtained in the drug resistance test before starting antiretrovirals (ARVs). HIV-1 subtypes and epidemiological surveillance mutations were determined using different bioinformatics tools. Logistic regression was used to estimate the association between predictor variables and late presentation (LP). Results: The median age was 31 years, 51% had a current income between 501-1,000 euros, 28% were migrants. 21% had never been tested for HIV before diagnosis, with 42.3% of MSM presenting LP. 60% were infected with subtype B strains. In the multivariate regression, increased age at diagnosis, higher income, lower frequency of screening, STI ever diagnosed and higher viral load were associated with LP. Conclusion: Our study suggests that specific subgroups of the MSM population, such older MSM, with higher income and lower HIV testing frequency, are not being targeted by community and clinical screening services. Overall, targeted public health measures should be strengthened toward these subgroups, through strengthened primary care testing, expanded access to PrEP, information and promotion of HIV self-testing and more inclusive and accessible health services.


Asunto(s)
Infecciones por VIH , Minorías Sexuales y de Género , Masculino , Humanos , Adulto , Homosexualidad Masculina , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Portugal/epidemiología , Europa (Continente)
14.
Plant Physiol ; 160(3): 1407-19, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22961129

RESUMEN

Stilbenes are a small family of phenylpropanoids produced in a number of unrelated plant species, including grapevine (Vitis vinifera). In addition to their participation in defense mechanisms in plants, stilbenes, such as resveratrol, display important pharmacological properties and are postulated to be involved in the health benefits associated with a moderate consumption of red wine. Stilbene synthases (STSs), which catalyze the biosynthesis of the stilbene backbone, seem to have evolved from chalcone synthases (CHSs) several times independently in stilbene-producing plants. STS genes usually form small families of two to five closely related paralogs. By contrast, the sequence of grapevine reference genome (cv PN40024) has revealed an unusually large STS gene family. Here, we combine molecular evolution and structural and functional analyses to investigate further the high number of STS genes in grapevine. Our reannotation of the STS and CHS gene families yielded 48 STS genes, including at least 32 potentially functional ones. Functional characterization of nine genes representing most of the STS gene family diversity clearly indicated that these genes do encode for proteins with STS activity. Evolutionary analysis of the STS gene family revealed that both STS and CHS evolution are dominated by purifying selection, with no evidence for strong selection for new functions among STS genes. However, we found a few sites under different selection pressures in CHS and STS sequences, whose potential functional consequences are discussed using a structural model of a typical STS from grapevine that we developed.


Asunto(s)
Aciltransferasas/química , Aciltransferasas/genética , Evolución Molecular , Familia de Multigenes/genética , Vitis/enzimología , Vitis/genética , Aciltransferasas/metabolismo , Agrobacterium/metabolismo , Aminoácidos/genética , Cromosomas de las Plantas/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Modelos Moleculares , Filogenia , Estilbenos/química , Estilbenos/metabolismo , Estrés Fisiológico/genética , Nicotiana/microbiología
15.
Cureus ; 15(1): e33686, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36788829

RESUMEN

Shewanella algae is a rod-shaped, Gram-negative bacterium that is considered an emerging human pathogen. Traditionally associated with warmer climates, S. algae has now been isolated from patients worldwide, and reports of infection are increasing. In a regional hospital on the outskirts of Lisbon, Portugal, four cases have been detected in the past 10 years. Two of the patients were migrants from African countries with daily contact with water; the other two patients were Portuguese, and no epidemiological risk factors were found among them. These are the first cases reported in Portugal. Risk factors associated with S. algae infection in patients discussed in this paper include the following: human immunodeficiency virus (HIV) infection, chronic venous insufficiency, lower limb ulcers, chronic kidney disease, diabetes, arterial hypertension, dilated cardiomyopathy, atrial fibrillation, chronic hepatic disease, and chronic pancreatitis. One patient died in the intensive care unit with septic shock and disseminated intravascular coagulation from a fulminant infection secondary to S. algae bacteraemia. The four clinical cases presented in this case series highlight the clinical features of this infection so that other physicians can successfully identify and treat S. algae infections.

16.
Proc Natl Acad Sci U S A ; 106(29): 11913-8, 2009 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-19571007

RESUMEN

Steroid hormones regulate many physiological processes in vertebrates, nematodes, and arthropods through binding to nuclear receptors (NR), a metazoan-specific family of ligand-activated transcription factors. The main steps controlling the diversification of this family are now well-understood. In contrast, the origin and evolution of steroid ligands remain mysterious, although this is crucial for understanding the emergence of modern endocrine systems. Using a comparative genomic approach, we analyzed complete metazoan genomes to provide a comprehensive view of the evolution of major enzymatic players implicated in steroidogenesis at the whole metazoan scale. Our analysis reveals that steroidogenesis has been independently elaborated in the 3 main bilaterian lineages, and that steroidogenic cytochrome P450 enzymes descended from those that detoxify xenobiotics.


Asunto(s)
Evolución Molecular , Hormonas/metabolismo , Transducción de Señal , Esteroides/metabolismo , Animales , Sistema Enzimático del Citocromo P-450/genética , Duplicación de Gen , Ligandos , Funciones de Verosimilitud , Modelos Genéticos , Oxidorreductasas/genética , Filogenia , Especificidad de la Especie , Vertebrados/genética
17.
Dysphagia ; 27(2): 277-83, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21874509

RESUMEN

The aim of this study was to analyze the presence and distribution of total collagen, type I and type III collagen, elastic fibers, fibronectin, and versican in the endomysium of cricopharyngeus muscles from adults of various ages. The study was a cross-sectional analysis of human cricopharyngeus muscles. Twenty-seven muscles obtained from autopsies of men and women ranging in age from 28 to 92 years were analyzed with the Picrosirius method, oxidized Weigert resorcin-fuchsin, immunohistochemistry, and image analysis. Collagen had the highest density among the analyzed components. Elastic fibers surrounded each muscle cell; they were aligned longitudinally by their long axis and associated with traversing fibers, thereby forming a fiber network with embedded muscle cells. The fibronectin and versican contents varied widely among the specimens. We found no statistically significant differences between the proportion of extracellular matrix (ECM) components and factors such as gender and race. We conclude that the higher proportion of type I and type III collagen is compatible with the cricopharyngeus muscle's sphincteric behavior, and the arrangement of the elastic fibers may also contribute to the muscle's elasticity. We found no statistically significant correlation between the ECM components and age.


Asunto(s)
Matriz Extracelular/química , Músculos Faríngeos/química , Adulto , Anciano , Anciano de 80 o más Años , Colágeno/análisis , Tejido Elástico , Femenino , Fibronectinas/análisis , Humanos , Masculino , Persona de Mediana Edad , Versicanos/análisis
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 265: 120384, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34536895

RESUMEN

In this work samples of historical pigments of green hue were brushed on a canvas and studied by Visible Reflectance, X-Ray Fluorescence and Fourier Transform Infrared Spectroscopy. One hundred samples were investigated, all with green hue, these prepared from pigments themselves green, such as chromium oxide (Cr2O3) or from a mixture of pigments that result in green, for example, chrome yellow (PbCrO4) and Prussian blue (Fe4[Fe(CN)6]3). Because every sample investigated through the spectroscopic techniques were of green hue, the characterization of the pigments present in the mixtures through the visual inspection of spectra has become a complex task in some cases, also, due the large number of recorded spectra. In this work, classification models were developed using the multivariate statistical method Partial Least Squares Discriminant Analysis (PLS-DA) to automate the characterization of the pigments present in the mixtures. The models were developed to classify chromium oxide (Cr2O3), chrome yellow (PbCrO4), cerulean blue (CoO.nSnO2) and yellow ochre (Fe2O3·H2O + clay + silica). The models were developed from the fusion of data from the three spectroscopic techniques. However, before data fusion, pre-treatments of the spectral data were tested for their influence on the PLS-DA models. The models developed with data from the three techniques made it possible to classify the pigments of interest in the samples with up to 100% effectiveness. The results also indicate that fusion of the data from the three techniques allows to obtain fingerprints of the pigments of interest, which is not always possible using data from only one or two of the techniques applied in this work.


Asunto(s)
Pigmentación , Análisis Discriminante , Análisis de los Mínimos Cuadrados , Espectroscopía Infrarroja por Transformada de Fourier
19.
Front Microbiol ; 13: 823208, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35558119

RESUMEN

Objective: To describe and analyze transmitted drug resistance (TDR) between 2014 and 2019 in newly infected patients with HIV-1 in Portugal and to characterize its transmission networks. Methods: Clinical, socioepidemiological, and risk behavior data were collected from 820 newly diagnosed patients in Portugal between September 2014 and December 2019. The sequences obtained from drug resistance testing were used for subtyping, TDR determination, and transmission cluster (TC) analyses. Results: In Portugal, the overall prevalence of TDR between 2014 and 2019 was 11.0%. TDR presented a decreasing trend from 16.7% in 2014 to 9.2% in 2016 (p for-trend = 0.114). Multivariate analysis indicated that TDR was significantly associated with transmission route (MSM presented a lower probability of presenting TDR when compared to heterosexual contact) and with subtype (subtype C presented significantly more TDR when compared to subtype B). TC analysis corroborated that the heterosexual risk group presented a higher proportion of TDR in TCs when compared to MSMs. Among subtype A1, TDR reached 16.6% in heterosexuals, followed by 14.2% in patients infected with subtype B and 9.4% in patients infected with subtype G. Conclusion: Our molecular epidemiology approach indicates that the HIV-1 epidemic in Portugal is changing among risk group populations, with heterosexuals showing increasing levels of HIV-1 transmission and TDR. Prevention measures for this subpopulation should be reinforced.

20.
J Pharm Biomed Anal ; 193: 113682, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-33166841

RESUMEN

Bryophyllum pinnatum (Lam.) Oken (Crassulaceae) is widely used as leaf juice or extracts in traditional medicine all over tropical areas, especially in Brazil, to relieve inflammation-associated symptoms. Flavonol glycosides with unusual sugar moiety are among the major metabolites. Nevertheless, there are not enough quality control studies that can contribute to authentication of B. pinnatum and determination of their markers. As it is also used as medicinal plant in several countries, it is necessary to provide data related to safety, efficacy and quality. In this context, this work aims to isolate the major flavonoids from B. pinnatum hydroethanolic extract, to validate a method to quantify the content of chemical markers and to evaluate their xanthine oxidase inhibition and antioxidant activity. The extract was submitted to centrifugal partition chromatography (CPC). The solvents system CyHex-EtOAc-EtOH-H2O, 0.5:9:3:5.5, v/v/v/v was selected by shake-flask method. Four flavonoids (quercetin 3-O-α-L-arabinopyranosyl-(1→2)-O-α-L-rhamnopyranoside (1), kaempferol 3-O-α-L-arabinopyranosyl-(1→2)-O-α-L-rhamnopyranoside (2), quercetin 3-O-α-L-rhamnopyranoside (3) and kaempferol 3-O-α-L-rhamnopyranoside (4)) were isolated in a single and fast CPC run and their structures were confirmed by NMR analysis. An UPLC-DAD quantification method was established for the first time with validation of required parameters, according to RDC 166/2017. The calibration curves were linear with correlation coefficient ranging from 0.9996 to 0.9997 while the values of LOD (0.0077-1.984 ng.mL-1), LOQ (0.0263-6.012 ng.mL-1), recovery (≥ 80.7 %) and inter-day (%RSD ≤ 3.581) and intra-day precision (%RSD ≤ 2.628) were satisfactory. Quantitative analysis of these compounds showed that the proportion of 1, 2 and 3 were 2.43, 0.25 and 0.33 % (24.3 mg.g-1, 0.25 mg.g-1 and 0.33 mg.g-1 of extract), respectively. Moreover, in vitro xanthine oxidase (XO), DPPH and ABTS inhibition were evaluated for the extract and the major flavonoids. Compounds 2 (168 µM) and 3 (124 µM) moderately inhibited XO, while compounds 1 and 3 displayed average radical scavenging activity. In conclusion, our results suggest the flavonoid 1 as a specific marker which may be used for quality control of B. pinnatum hydroethanolic leaves extract.


Asunto(s)
Kalanchoe , Brasil , Flavonoides , Extractos Vegetales/farmacología , Hojas de la Planta
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