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1.
Photochem Photobiol Sci ; 23(9): 1757-1769, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39242437

RESUMO

Porphyrazines (Pzs) are porphyrin derivatives that show potential application as photosensitizers for photodynamic therapy (PDT), but are still far less explored in the literature. In this work, we evaluate how the photophysics and phototoxicity of the octakis(trifluoromethylphenyl)porphyrazine (H2Pz) against tumor cells can be modulated by coordination with Mg(II), Zn(II), Cu(II) and Co(II) ions. Fluorescence and singlet oxygen quantum yields for the Pzs were measured in organic solvents and in soy phosphatidylcholine (PC) liposomes suspended in water. While H2Pz and the respective complexes with Cu(II) and Co(II) showed very low efficiency to fluoresce and to produce 1O2, the Mg(II) and Zn(II) complexes showed significantly higher quantum yields in organic solvents. The fluorescence of these two Pzs in the liposomes was sensitive to the fluidity of the membrane, showing potential use as viscosity markers. The cytotoxicity of the compounds was tested in HaCaT (normal) and A431 (tumor) cells using soy PC liposomes as drug carriers. Despite the low 1O2 quantum yields in water, the Mg(II) and Zn(II) complexes showed IC50 values against A431 cells in the nanomolar range when activated with low doses of red LED light. Their phototoxicity was ca. three times higher for the tumor cells compared to the normal ones, showing promising application as photosensitizers for PDT protocols. Considering that H2Pz and the respective Co(II) and Cu(II) complexes were practically non-phototoxic to the cells, we demonstrate the importance of the central metal ion in the modulation of the photodynamic activity of porphyrazines.


Assuntos
Lipossomos , Fármacos Fotossensibilizantes , Porfirinas , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Porfirinas/química , Porfirinas/farmacologia , Lipossomos/química , Fotoquimioterapia , Oxigênio Singlete/metabolismo , Oxigênio Singlete/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Zinco/química , Zinco/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Íons/química
2.
J Immunother Cancer ; 12(9)2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39299754

RESUMO

BACKGROUND: Major histocompatibility complex class I (MHC-I) loss is frequent in non-small cell lung cancer (NSCLC) rendering tumor cells resistant to T cell lysis. NK cells kill MHC-I-deficient tumor cells, and although previous work indicated their presence at NSCLC margins, they were functionally impaired. Within, we evaluated whether NK cell and CD8 T cell infiltration and activation vary with MHC-I expression. METHODS: We used single-stain immunohistochemistry (IHC) and Kaplan-Meier analysis to test the effect of NK cell and CD8 T cell infiltration on overall and disease-free survival. To delineate immune covariates of MHC-I-disparate lung cancers, we used multiplexed immunofluorescence (mIF) imaging followed by multivariate statistical modeling. To identify differences in infiltration and intercellular communication between IFNγ-activated and non-activated lymphocytes, we developed a computational pipeline to enumerate single-cell neighborhoods from mIF images followed by multivariate discriminant analysis. RESULTS: Spatial quantitation of tumor cell MHC-I expression revealed intratumoral and intertumoral heterogeneity, which was associated with the local lymphocyte landscape. IHC analysis revealed that high CD56+ cell numbers in patient tumors were positively associated with disease-free survival (HR=0.58, p=0.064) and overall survival (OS) (HR=0.496, p=0.041). The OS association strengthened with high counts of both CD56+ and CD8+ cells (HR=0.199, p<1×10-3). mIF imaging and multivariate discriminant analysis revealed enrichment of both CD3+CD8+ T cells and CD3-CD56+ NK cells in MHC-I-bearing tumors (p<0.05). To infer associations of functional cell states and local cell-cell communication, we analyzed spatial single-cell neighborhood profiles to delineate the cellular environments of IFNγ+/- NK cells and T cells. We discovered that both IFNγ+ NK and CD8 T cells were more frequently associated with other IFNγ+ lymphocytes in comparison to IFNγ- NK cells and CD8 T cells (p<1×10-30). Moreover, IFNγ+ lymphocytes were most often found clustered near MHC-I+ tumor cells. CONCLUSIONS: Tumor-infiltrating NK cells and CD8 T cells jointly affected control of NSCLC tumor progression. Coassociation of NK and CD8 T cells was most evident in MHC-I-bearing tumors, especially in the presence of IFNγ. Frequent colocalization of IFNγ+ NK cells with other IFNγ+ lymphocytes in near-neighbor analysis suggests NSCLC lymphocyte activation is coordinately regulated.


Assuntos
Linfócitos T CD8-Positivos , Carcinoma Pulmonar de Células não Pequenas , Antígenos de Histocompatibilidade Classe I , Células Matadoras Naturais , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Masculino , Feminino , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo
3.
J Vet Diagn Invest ; : 10406387241273909, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267415

RESUMO

Congenital malformations are a highly diverse group of conditions reported in both humans and animals, characterized by defects in morphogenesis observed at birth. Although most cases are idiopathic, genetic and environmental factors may be involved. The frequency of such conditions varies with species, geographic regions, and the specific malformation involved. In polymelia, supernumerary limbs are attached to different parts of the body. Gastrointestinal duplications are described less frequently and can be associated with polymelia. Cloacal atresia is among the least-reported malformations in avian species, described only once in a kiwi. Here we describe a case with these 3 malformations in a single broiler chick (Gallus gallus domesticus) and provide a literature review about the occurrence of these malformations in birds. The 3-d-old chick also had an unidentified structure projecting from the pygostyle region. We performed clinical, radiographic, and postmortem examinations. The intestinal duplication was identified only during the postmortem evaluation. Detailed descriptions of avian congenital malformations are scarce. Although similar cases have been reported, we retrieved no cases of concurrent polymelia, intestinal duplication, and cloacal atresia in broiler chickens in our literature search, suggesting that the simultaneous occurrence of these conditions has not been reported previously in this species.

4.
J Clin Med ; 13(17)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39274514

RESUMO

Background: 25 to 50% of patients suffering from colorectal cancer develop liver metastases. The incidence of regional lymph node (LN) metastases within the liver is up to 14%. The need for perihilar lymph node dissection (LND) is still a controversial topic in patients with colorectal liver metastases (CRLM). This study investigates the role of perihilar LND in patients with CRLM. Methods: For this retrospective study, patients undergoing surgery for CRLM at the University Hospital Basel between May 2009 and December 2021 were included. In patients with perihilar LND, LN were stained for CK22 and examined for single tumour cells (<0.2 mm), micro- (0.2-2 mm), and macro-metastases (>2 mm). Results: 112 patients undergoing surgery for CRLM were included. 54 patients underwent LND, 58/112 underwent liver resection only (LR). 3/54 (5.6%) showed perihilar LN metastases in preoperative imaging, and in 10/54 (18.5%), micro-metastases could be proven after CK22 staining. Overall complications were similar in both groups (LND: 46, 85.2%; LR: 48, 79.3%; p = 0.800). The rate of major complications was higher in the LND group (LND: 22, 40.7%; LR: 18, 31%, p = 0.002). Median recurrence-free survival (RFS) (LND: 10 months; LR: 15 months, p = 0.076) and overall survival (OS) were similar (LND: 49 months; LR: 60 months, p = 0.959). Conclusion: Preoperative imaging is not sensitive enough to detect perihilar LN metastases. Perihilar LND enables precise tumour staging by detecting more lymph node metastases, especially through CK22 staining. However, perihilar LND does not influence oncologic outcomes in patients with CRLM.

5.
mBio ; 15(9): e0192224, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39140770

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic caused the biggest public health crises in recent history. Many expect future coronavirus introductions into the human population. Hence, it is essential to understand the basic biology of these viruses. In natural infection, the SARS-CoV-2 Spike (S) glycoprotein is co-expressed with all other viral proteins, which modify cellular compartments to maximize virion assembly. By comparison, most of S is degraded when the protein is expressed in isolation, as in current molecular vaccines. To probe the maturation pathway of S, we redirected its maturation by fusing S to the tetraspanin protein CD81. CD81 is a defining constituent of extracellular vesicles (EVs) or exosomes. EVs are generated in large numbers by all cells, extruded into blood and lymph, and transfer cargo between cells and systemically (estimated 1012 EVs per mL plasma). EVs, like platelets, can be transfused between unrelated donors. When fusing the proline-stabilized form of strain Delta S into the flexible, large extracellular loop of CD81 rather than being degraded in the lysosome, S was extruded into EVs. CD81-S fusion containing EVs were produced in large numbers and could be isolated to high purity. Purified CD81::S EVs bound ACE2, and S displayed on individual EV was observed by cryogenic electron microscopy (EM). The CD81::S-fusion EVs were non-toxic and elicited an anti-S trimer and anti-RBD antibody response in mice. This report shows a design path to maximize viral glycoprotein assembly and release without relying on the co-expression of potentially pathogenic nonstructural viral proteins. IMPORTANCE: The severe acute respiratory syndrome coronavirus 2 pandemic caused the biggest public health crises in recent history. To understand the maturation pathway of S, we fused S to the tetraspanin protein CD81. The resulting molecule is secreted in extracellular vesicles and induces antibodies in mice. This may be a general design path for viral glycoprotein vaccines.


Assuntos
SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Tetraspanina 28 , Animais , Humanos , Camundongos , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , COVID-19/virologia , COVID-19/imunologia , Vesículas Extracelulares/metabolismo , Transporte Proteico , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Tetraspanina 28/metabolismo , Tetraspanina 28/genética
6.
Pregnancy Hypertens ; 37: 101150, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39146694

RESUMO

OBJECTIVE: To explore the association between serum levels and food intake of Vitamin D (VD) among healthy women in mid-pregnancy and preeclampsia. STUDY DESIGN: In a Brazilian multicentre cohort of healthy nulliparous pregnant women from five maternity centres we developed a nested case-control analysis comparing cases with and without preeclampsia. Women were enrolled and followed during prenatal care, including only singleton pregnancies, without any fetal malformations or previous chronic maternal disease. We matched 87 cases of preeclampsia to eligible controls randomly selected in a 1:1 ratio, by age and region. MAIN OUTCOME MEASURES: Blood samples from these were collected, and a 24-hour recall of food intake was obtained in mid-pregnancy, between 19 and 21 weeks. VD serum levels (25-hydroxyvitamin D) were measured by liquid chromatography-tandem mass spectrometry and were categorized as deficient, insufficient, and sufficient. The dietary intake of VD was estimated with the 24-hour diet recall applied at the same time and from supplementation. Maternal characteristics and VD levels were compared between cases and controls with OR and respective 95 %CI. Multivariate analysis using the Path method was used to assess relationships among VD, PE, BMI, skin colour/ethnicity, and diet. RESULTS: The maternal characteristics of both groups were similar, except for the higher occurrence of obesity among women with preeclampsia (OR 3.47, 95 %CI 1.48-8.65). Dietary intake of VD was similar in both groups, and most of the women in both groups consumed insufficient VD (82.2 vs 79.3 % in the groups with and without PE). CONCLUSIONS: Levels and dietary intake of VD were not associated with PE in this Brazilian sample of healthy pregnant women; however, BMI and skin colour/ethnicity were associated with PE.


Assuntos
Pré-Eclâmpsia , Segundo Trimestre da Gravidez , Vitamina D , Humanos , Feminino , Gravidez , Pré-Eclâmpsia/sangue , Adulto , Brasil/epidemiologia , Vitamina D/sangue , Vitamina D/análogos & derivados , Vitamina D/administração & dosagem , Estudos de Casos e Controles , Segundo Trimestre da Gravidez/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia , Adulto Jovem
7.
Women Health ; 64(8): 636-647, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39155146

RESUMO

The increased prevalence of autism spectrum disorder (ASD) has placed a significant emotional and psychological burden on mothers. We explored the association between the severity of ASD symptoms in children and the mental health of their mothers during the COVID-19 pandemic. Our study included 1,924 mothers of children with ASD, enrolled in a web-based cross-sectional survey over 85 consecutive days to gather clinical and sociodemographic data. The severity of ASD symptoms was obtained according to the children's age. Using the Depression, Anxiety, and Stress Scales (DASS-21) scale, we found that 35.8 percent of mothers experienced both anxiety and depression. A high education level and a high family income reduced the chance of concurrent anxiety and depression. Conversely, unemployment, a child using psychiatric medication, and higher severity of ASD symptoms increased the chance. Notably, the severity of the ASD symptom was the sole predictor of maternal co-occurring anxiety and depression across all age groups (<3 years aOR = 2.04, 95%CI 1.07-3.89; 3-5 years aOR = 2.76, 95%CI 1.67-4.56; ≥ 6 years aOR = 1.61, 95%CI 1.04-2.50). Recognizing the challenges associated with ASD leads to greater acceptance and tailored interventions, ultimately improving the overall well-being of both individuals with ASD and their mothers.


Assuntos
Ansiedade , Transtorno do Espectro Autista , COVID-19 , Depressão , Saúde Mental , Mães , Humanos , Transtorno do Espectro Autista/psicologia , Transtorno do Espectro Autista/epidemiologia , Mães/psicologia , Estudos Transversais , Feminino , Adulto , Ansiedade/epidemiologia , Ansiedade/psicologia , Depressão/epidemiologia , Depressão/psicologia , Criança , Pré-Escolar , COVID-19/psicologia , COVID-19/epidemiologia , Masculino , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia , SARS-CoV-2 , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Inquéritos e Questionários
8.
Chembiochem ; : e202400018, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39159394

RESUMO

Steroid hormones are essential for the biological processes of eukaryotic organisms. The steroid endocrine system of C. elegans, which includes dafachronic acids (DA) and the nuclear receptor ceDAF-12, provides a simple model for exploring the role of steroid hormone signaling pathways in animals. In this study, we show for the first time the feasibility of designing synthetic steroids that can modulate different physiological processes, such as development, reproduction and ageing, in relation to ceDAF-12. Our results not only confirm the conclusions derived from genetic studies linking these processes but also provide new chemical tools to selectively manipulate them, as we found that different compounds produce different phenotypic results. The structures of these compounds are much more diverse than those of endogenous hormones and analogues previously described by other researchers, allowing further development of the chemical modulation of the steroid endocrine system in C. elegans and related nematodes.

9.
bioRxiv ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38979183

RESUMO

Background: MHC class I (MHC-I) loss is frequent in non-small cell lung cancer (NSCLC) rendering tumor cells resistant to T cell lysis. NK cells kill MHC-I-deficient tumor cells, and although previous work indicated their presence at NSCLC margins, they were functionally impaired. Within, we evaluated whether NK cell and CD8 T cell infiltration and activation vary with MHC-I expression. Methods: We used single-stain immunohistochemistry (IHC) and Kaplan-Meier analysis to test the effect of NK cell and CD8 T cell infiltration on overall and disease-free survival. To delineate immune covariates of MHC-I-disparate lung cancers, we used multiplexed immunofluorescence (mIF) imaging followed by multivariate statistical modeling. To identify differences in infiltration and intercellular communication between IFNγ-activated and non-activated lymphocytes, we developed a computational pipeline to enumerate single cell neighborhoods from mIF images followed by multivariate discriminant analysis. Results: Spatial quantitation of tumor cell MHC-I expression revealed intra- and inter-tumoral heterogeneity, which was associated with the local lymphocyte landscape. IHC analysis revealed that high CD56+ cell numbers in patient tumors were positively associated with disease-free survival (DFS) (HR=0.58, p=0.064) and overall survival (OS) (HR=0.496, p=0.041). The OS association strengthened with high counts of both CD56+ and CD8+ cells (HR=0.199, p<1×10-3). mIF imaging and multivariate discriminant analysis revealed enrichment of both CD3+CD8+ T cells and CD3-CD56+ NK cells in MHC-I-bearing tumors (p<0.05). To infer associations of functional cell states and local cell-cell communication, we analyzed spatial single cell neighborhood profiles to delineate the cellular environments of IFNγ+/- NK cells and T cells. We discovered that both IFNγ+ NK and CD8 T cells were more frequently associated with other IFNγ+ lymphocytes in comparison to IFNγ- NK cells and CD8 T cells (p<1×10-30). Moreover, IFNγ+ lymphocytes were most often found clustered near MHC-I+ tumor cells. Conclusions: Tumor-infiltrating NK cells and CD8 T cells jointly affected control of NSCLC tumor progression. Co-association of NK and CD8 T cells was most evident in MHC-I-bearing tumors, especially in the presence of IFNγ. Frequent co-localization of IFNγ+ NK cells with other IFNγ+ lymphocytes in near-neighbor analysis suggests NSCLC lymphocyte activation is coordinately regulated.

10.
Curr Res Toxicol ; 7: 100181, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39021403

RESUMO

Sickle cell disease (SCD) is an inherited hemoglobin disorder marked by red blood cell sickling, resulting in severe anemia, painful episodes, extensive organ damage, and shortened life expectancy. In SCD, increased iron levels can trigger ferroptosis, a specific type of cell death characterized by reactive oxygen species (ROS) and lipid peroxide accumulation, leading to damage and organ impairments. The intricate interplay between iron, ferroptosis, inflammation, and oxidative stress in SCD underscores the necessity of thoroughly understanding these processes for the development of innovative therapeutic strategies. This review highlights the importance of balancing the complex interactions among various factors and exploitation of the knowledge in developing novel therapeutics for this devastating disease.

11.
J Phys Chem A ; 128(28): 5586-5604, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38954748

RESUMO

High-level electronic structure calculations were conducted to examine the bonding and spectroscopic properties of the UO0/± and UF0/± diatomic molecules. The low-lying Ω states were described by using multireference SO-CASPT2 calculations. The adiabatic electronic affinity (AEA), adiabatic ionization energy (IE), and bond dissociation energy (BDE) were calculated at the Feller-Peterson-Dixon (FPD) level. The ground state of UO is predicted to be 5I4, and that of UF is 4I9/2. The calculated AEAs of UO and UF are 1.123 and 0.453 eV, respectively, and the corresponding IEs are 5.976 and 6.278 eV. The BDE of UO (749.5 kJ/mol) is predicted to be considerably higher than that of UF (627.2 kJ/mol), and both are higher than those predicted for UB, UC, and UN. NBO calculations show strong ionic character for the ground states of UO and UF and bond orders that range from 2 to 3 and from 1 to 2, respectively. Comparisons of the calculated properties to those of the series comprising UB, UC, and UN diatomic molecules are given.

12.
Toxins (Basel) ; 16(7)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39057948

RESUMO

Currently, the search for new alternatives to conventional antibiotics to combat bacterial resistance is an urgent task, as many microorganisms threaten human health due to increasing bacterial resistance to traditional medicines. Thus, new molecules such as antimicrobial peptides have emerged as promising alternatives because of their low induction of resistance and broad spectrum of action. In this context, in the past few years, our research group has synthesized and characterized a peptide derived from the C-terminal region of the Lys49 PLA2-like BthTX-I, named p-BthTX-I. After several studies, the peptide (p-BthTX-I)2K was proposed as the molecule with the most considerable biotechnological potential. As such, the present work aimed to evaluate whether the modifications made on the peptide (p-BthTX-I)2K can be applied to other molecules originating from the C-terminal region of PLA2-like Lys49 from snake venoms. The peptides were obtained through the solid-phase peptide synthesis technique, and biochemical and functional characterization was carried out using dichroism techniques, mass spectrometry, antimicrobial activity against ESKAPE strains, hemolytic activity, and permeabilization of lipid vesicles. The antimicrobial activity of the peptides was promising, especially for the peptides (p-AppK)2K and (p-ACL)2K, which demonstrated activity against all strains that were tested, surpassing the model molecule (p-BthTX-I)2K in most cases and maintaining low hemolytic activity. The modifications initially proposed for the (p-BthTX-I)2K peptide were shown to apply to other peptides derived from Lys49 PLA2-like from snake venoms, showing promising results for antimicrobial activity. Future assays comparing the activity of the dimers obtained through this strategy with the monomers of these peptides should be carried out.


Assuntos
Fosfolipases A2 , Fosfolipases A2/farmacologia , Fosfolipases A2/química , Hemólise/efeitos dos fármacos , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/síntese química , Animais , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Humanos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/síntese química , Bactérias/efeitos dos fármacos
13.
Chem Biodivers ; : e202400318, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073233

RESUMO

Paper spray ionization (PSI-MS) and tissue spray ionization (TSI-MS) mass spectrometry are simple and rapid ambient ionization mass spectrometry techniques that offer numerous advantages over conventional analysis methods. This study aims to analyze the efficiency of detecting anthocyanins from Eugenia jambolana fruit peel and Inga edulis seeds using PSI-MS, TSI-MS, and DI-MS (direct infusion). DI-MS exhibited high efficiency, detecting all compounds in abundance, with anthocyanins malvidin 3,5-O-diglucoside (1) and petunidin 3,5-O-diglucoside (2) being the most prevalent. PSI-MS, however, struggled to detect delphinidin 3-O-glucoside and showed lower abundances for compounds 1, 2, 3 (delphinidin 3,5-O-diglucoside), and 4 (petunidin 3-O-glucoside) compared to DI-MS, attributed to the technique's challenges with molecular weight and polarity. TSI-MS was least effective, detecting only compounds 1, 2, and 3 at low intensities. The overall unique compounds identified across techniques were 134, emphasizing the importance of comprehensively employing multiple methods to analyze anthocyanins in these edible plants.

14.
J Chem Inf Model ; 64(15): 6115-6131, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39046235

RESUMO

α-Synuclein (α-syn) is a 140 amino acid intrinsically disordered protein (IDP) and the primary component of cytotoxic oligomers implicated in the etiology of Parkinson's disease (PD). While IDPs lack a stable three-dimensional structure, they sample a heterogeneous ensemble of conformations that can, in principle, be assessed through molecular dynamics simulations. However, describing the structure and aggregation of large IDPs is challenging due to force field (FF) accuracy and sampling limitations. To cope with the latter, coarse-grained (CG) FFs emerge as a potential alternative at the expense of atomic detail loss. Whereas CG models can accurately describe the structure of the monomer, less is known about aggregation. The latter is key for assessing aggregation pathways and designing aggregation inhibitor drugs. Herein, we investigate the structure and dynamics of α-syn using different resolution CG (Martini3 and Sirah2) and all-atom (Amber99sb and Charmm36m) FFs to gain insight into the differences and resemblances between these models. The dependence of the magnitude of protein-water interactions and the putative need for enhanced sampling (replica exchange) methods in CG simulations are analyzed to distinguish between force field accuracy and sampling limitations. The stability of the CG models of an α-syn fibril was also investigated. Additionally, α-syn aggregation was studied through umbrella sampling for the CG models and CG/all-atom models for an 11-mer peptide (NACore) from an amyloidogenic domain of α-syn. Our results show that despite the α-syn structures of Martini3 and Sirah2 with enhanced protein-water interactions being similar, major differences exist concerning aggregation. The Martini3 fibril is not stable, and the binding free energy of α-syn and NACore is positive, opposite to Sirah2. Sirah2 peptides in a zwitterionic form, in turn, display termini interactions that are too strong, resulting in end-to-end orientation. Sirah2, with enhanced protein-water interactions and neutral termini, provides, however, a peptide aggregation free energy profile similar to that found with all-atom models. Overall, we find that Sirah2 with enhanced protein-water interactions is suitable for studying protein-protein and protein-drug aggregation.


Assuntos
Simulação de Dinâmica Molecular , Agregados Proteicos , alfa-Sinucleína , Humanos , alfa-Sinucleína/química , Conformação Proteica
15.
Actual. nutr ; 25(2): 89-97, abr.jun.2024.
Artigo em Espanhol | LILACS | ID: biblio-1562045

RESUMO

l estrés académico puede presentarse en estudiantes sometidos a diversas exigencias y requisitos universitarios, provocando diferentes reacciones de estrés, físicas, psicológicas y comportamentales, reduciendo su calidad de vida y provocando consecuencias como: depresión, tristeza, fatiga y dolores de cabeza, afectando su estado nutricional. Se investigó la relación entre ingesta de alimentos y estrés académico en estudiantes del cuarto semestre de la Licenciatura en Medicina de la Universidad Autónoma de Chihuahua. La población de estudio, dado el carácter piloto de la investigación, se realizó mediante muestreo simple, aleatorio, sin reemplazo, con un diseño mixto, descriptivo, comparativo y transversal, utilizándose el cálculo del tamaño muestral con un intervalo de confianza de 95%, resultando N=117; 51 hombres y 66 mujeres entre 19 y 43 años de la generación 2019, a quienes se les aplicó el inventario SISCO de estrés académico. Se encontró mayor frecuencia en situaciones que provocan preocupación y nerviosismo, sobrecarga de tareas y trabajo, inquietud, problemas de concentración, fatiga crónica y apatía. Las estrategias más utilizadas fueron: desarrollo de planes y ejecución de tareas y capacidad asertiva. El 92.2% (n=108) de la población encuestada manifestó preocupación y nerviosismo, resultando 52,1% (n=61) en mujeres y 40.1% (n=47) en hombres. El 38.5% (n=45) de las mujeres entre 21 y 43 años, muestran una mayor relación entre aumentar o reducir el consumo de alimentos en correspondencia con sentimientos de depresión y tristeza. El estrés académico, suele estar relacionado con diferentes manifestaciones psicológicas, físicas y conductuales, que pueden influir directamente en la población estudiantil, afectando gravemente sus hábitos alimenticios y nutricionales


Academic stress can occur in students subjected to various university demands and requirements, causing different, causing different physical, psychological and behavioral reactions. Reducing quality of life and causing consequences such as: depression, sadness, fatigue and headaches, affecting their nutritional status. The relationship between food intake and academic stress was investigated in students in the fourth semester of the Bachelor of Medicine at the Autonomous University of Chihuahua. The study population, given the pilot nature of the research, was carried out through simple, random sampling, without replacement, with a mixed, descriptive, comparative and transversal design, using the sample size calculation with a 95% confidence interval resulting in N=117; 51 men and 66 women between the ages of 19 and 43, from the 2019 generation, to whom the SISCO inventory of academic stress was applied. A greater frequency was found in situations that cause worry and nervousness, overload of tasks and work, restlessness, concentration problems, chronic fatigue and listlessness. The most used strategies were plan development and execution of tasks and assertive ability. 92.2% (n=108) of the surveyed population expressed concern and nervousness, in 52.1% (n=61) women and 40.1% (n=47) men. The 38.5% (n=45) of women between 21 and 43 years old show a greater relationship between increasing or reducing food consumption in correspondence with feelings of depression and sadness. Academic stress is usually related to different psychological, physical and behavioral manifestations, which can directly influence the student population, seriously affecting their eating and nutritional habits


Assuntos
Estresse Psicológico , Ingestão de Alimentos , Adulto
16.
J Mycol Med ; 34(3): 101490, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38852225

RESUMO

Due to large outbreaks observed worldwide, Candida auris has emerged as a major threat to healthcare facilities. To prevent these phenomena, a systematic screening should be performed in patients transferred from regions where the pathogen is highly endemic. In this study, we recorded and analyzed French mycologists' current knowledge and practice regarding C. auris screening and diagnosis. Thirty-six centers answered an online questionnaire. Only 11 (30.6 %) participants were aware of any systematic screening for C. auris for patients admitted to their hospital. In the case of post-admission screening, axillae/groins (n = 21), nares (n = 7), rectum (n = 9), and mouth (n = 6) alone or various combinations were the body sites the most frequently sampled. Only six centers (8.3 %) reported using a commercially available plate allowing the differentiation of C. auris colonies from that of other Candida species, while five laboratories (13.8 %) had implemented a C. auris-specific qPCR. Considering the potential impact on infected patients and the risk of disorganization in the care of patients, it is crucial to remember to biologists and clinicians the utmost importance of systematic screening on admission.


Assuntos
Candida auris , Candidíase , Programas de Rastreamento , Humanos , França/epidemiologia , Inquéritos e Questionários , Candidíase/diagnóstico , Candidíase/epidemiologia , Candidíase/microbiologia , Programas de Rastreamento/métodos , Candida auris/efeitos dos fármacos , Candida auris/genética , Candida auris/isolamento & purificação , Conhecimentos, Atitudes e Prática em Saúde , Micologia/métodos , Sociedades Médicas , Candida/isolamento & purificação , Candida/efeitos dos fármacos , Candidíase Invasiva
17.
Nat Prod Res ; : 1-11, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829275

RESUMO

This work aimed to rectify Cunila galioides essential oil and evaluate the raw oil and the fractions' antifungal, allelopathic, and antioxidant activities. The results showed that the raw essential oil and the bottom fraction were primarily composed of linalyl propionate (42.9 wt.% and 60.2 wt.%). The top fraction was composed mainly of limonene (45.7 wt.%). The antioxidant activity changed with the radical and the fraction. The bottom had a weaker antifungal effect than the raw oil and the top. Nevertheless, the essential oil and the fractions had a similar antifungal activity at 0.50 % v/v and higher. Similar behavior was observed for the allelopathic tests. No difference occurred between the raw oil and the fractions, with reduced germination percentages and speed at 0.25 % v/v and complete inhibition at 0.50 % v/v. The oil can be rectified, and the fractions may be used without harming their biological activity.

18.
Sci Rep ; 14(1): 12875, 2024 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-38834639

RESUMO

The millions of specimens stored in entomological collections provide a unique opportunity to study historical insect diversity. Current technologies allow to sequence entire genomes of historical specimens and estimate past genetic diversity of present-day endangered species, advancing our understanding of anthropogenic impact on genetic diversity and enabling the implementation of conservation strategies. A limiting challenge is the extraction of historical DNA (hDNA) of adequate quality for sequencing platforms. We tested four hDNA extraction protocols on five body parts of pinned false heath fritillary butterflies, Melitaea diamina, aiming to minimise specimen damage, preserve their scientific value to the collections, and maximise DNA quality and yield for whole-genome re-sequencing. We developed a very effective approach that successfully recovers hDNA appropriate for short-read sequencing from a single leg of pinned specimens using silica-based DNA extraction columns and an extraction buffer that includes SDS, Tris, Proteinase K, EDTA, NaCl, PTB, and DTT. We observed substantial variation in the ratio of nuclear to mitochondrial DNA in extractions from different tissues, indicating that optimal tissue choice depends on project aims and anticipated downstream analyses. We found that sufficient DNA for whole genome re-sequencing can reliably be extracted from a single leg, opening the possibility to monitor changes in genetic diversity maintaining the scientific value of specimens while supporting current and future conservation strategies.


Assuntos
DNA , Animais , DNA/isolamento & purificação , DNA/genética , Borboletas/genética , DNA Mitocondrial/genética , Manejo de Espécimes/métodos , Lepidópteros/genética , Estudos Retrospectivos , Variação Genética , Genoma de Inseto , Análise de Sequência de DNA/métodos
19.
Genes (Basel) ; 15(6)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38927622

RESUMO

BACKGROUND: Malaria results in more than 550,000 deaths each year due to drug resistance in the most lethal Plasmodium (P.) species P. falciparum. A full P. falciparum genome was published in 2002, yet 44.6% of its genes have unknown functions. Improving the functional annotation of genes is important for identifying drug targets and understanding the evolution of drug resistance. RESULTS: Genes function by interacting with one another. So, analyzing gene co-expression networks can enhance functional annotations and prioritize genes for wet lab validation. Earlier efforts to build gene co-expression networks in P. falciparum have been limited to a single network inference method or gaining biological understanding for only a single gene and its interacting partners. Here, we explore multiple inference methods and aim to systematically predict functional annotations for all P. falciparum genes. We evaluate each inferred network based on how well it predicts existing gene-Gene Ontology (GO) term annotations using network clustering and leave-one-out crossvalidation. We assess overlaps of the different networks' edges (gene co-expression relationships), as well as predicted functional knowledge. The networks' edges are overall complementary: 47-85% of all edges are unique to each network. In terms of the accuracy of predicting gene functional annotations, all networks yielded relatively high precision (as high as 87% for the network inferred using mutual information), but the highest recall reached was below 15%. All networks having low recall means that none of them capture a large amount of all existing gene-GO term annotations. In fact, their annotation predictions are highly complementary, with the largest pairwise overlap of only 27%. We provide ranked lists of inferred gene-gene interactions and predicted gene-GO term annotations for future use and wet lab validation by the malaria community. CONCLUSIONS: The different networks seem to capture different aspects of the P. falciparum biology in terms of both inferred interactions and predicted gene functional annotations. Thus, relying on a single network inference method should be avoided when possible. SUPPLEMENTARY DATA: Attached.


Assuntos
Redes Reguladoras de Genes , Plasmodium falciparum , Plasmodium falciparum/genética , Malária Falciparum/parasitologia , Malária Falciparum/genética , Humanos , Ontologia Genética , Anotação de Sequência Molecular/métodos , Proteínas de Protozoários/genética
20.
Phys Chem Chem Phys ; 26(26): 18244-18255, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38904333

RESUMO

Natural deep eutectic solvents (NADESs) comprised of osmolytes are of interest as potential biomolecular (cryo)protectants. However, the way these solvents influence the structure and dynamics of biomolecules as well as the role of water remains poorly understood. We carried out principal component analysis of various secondary structure elements of ubiquitin in water and a betaine : glycerol : water (1 : 2 : ζ; ζ = 0, 1, 2, 5, 10, 20, 45) NADES, from molecular dynamics trajectories, to gain insight into the protein dynamics as it undergoes a transition from a highly viscous anhydrous to an aqueous environment. A crossover of the protein's essential dynamics at ζ ∼ 5, induced by solvent-shell coupled fluctuations, is observed, indicating that ubiquitin might (re)fold in the NADES upon water addition at ζ > ∼5. Further, in contrast to water, the anhydrous NADES preserves ubiquitin's essential modes at high temperatures explaining the protein's seemingly enhanced thermal stability.


Assuntos
Ubiquitina , Água , Betaína/química , Glicerol/química , Simulação de Dinâmica Molecular , Análise de Componente Principal , Estrutura Secundária de Proteína , Solventes/química , Ubiquitina/química , Água/química
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