RESUMEN
This dataset was compiled to estimate the levels of thermal comfort and mental health in a sample group of university students confined due to the COVID-19 pandemic. By the time research was carried out, these students of a hot and humid region of Mexico, had already spent 200 days on distance learning using online platforms. A total of 324 records were documented with a final sample of 316 valid participants. The total records were collected directly from the students through a web platform (Microsoft forms). This data set can be used to generate correlations between mental health, thermal comfort, and individual characteristics in the study population that will allow to identify the influence of the built environment and local climate on the levels of stress and anxiety that university students experienced under confinement. It can also be used to issue recommendations to improve the quality of built spaces and for the construction of adaptive models of thermal comfort considering mental health as a study variable.
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Recurrent glenohumeral dislocation is usually associated with bone loss of the glenoid portion, with the anteroinferior location being the most affected. The understanding of the related structures, as well as the use of current imaging studies such as computed axial tomography and magnetic resonance imaging, have made progress in understanding the pathology, as well as the development of surgical materials and minimally invasive tools, they allow us to continue innovating with respect to the previously described treatments, being possible to intervene in technical details with the intention of improving the results. That is why we have done what described by Eden-Hybinette, using tricortical cadaveric graft and as fixation method, limiting the comorbidities associated with the autograft taking, resulting a wide benefit for the patient, during the surgical procedure and in the recovery period.
La luxación glenohumeral recurrente suele asociarse a pérdida ósea de la porción glenoidea, siendo la localización anteroinferior la más afectada. El entendimiento de las estructuras relacionadas así como el uso de estudios de imagen actuales tales como la tomografía axial computarizada y la resonancia magnética han permitido avanzar respecto a la comprensión de la patología, asimismo el desarrollo de materiales quirúrgicos y herramientas de mínima invasión nos permiten continuar innovando respecto a los tratamientos previamente descritos, siendo posible intervenir en detalles técnicos con la intención de mejorar los resultados. Es por eso que hemos realizado lo descrito por Eden-Hybinette utilizando injerto tricortical cadavérico con tornillos canulados como método de fijación, limitando las comorbilidades asociadas a la toma de autoinjerto, dando como resultado un amplio beneficio para el paciente durante el procedimiento quirúrgico y en el período de recuperación.
Asunto(s)
Inestabilidad de la Articulación , Luxación del Hombro , Articulación del Hombro , Trasplante Óseo , Cadáver , Humanos , Escápula , Luxación del Hombro/diagnóstico por imagen , Luxación del Hombro/cirugía , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/cirugíaRESUMEN
BACKGROUND: Vitiligo is a pigmentation disorder of autoimmune aetiology. Polymorphisms in beta-defensin genes have been linked to a predisposition to some autoimmune disorders. AIM: To evaluate the role of polymorphisms in DEFB1, the gene encoding for human beta-defensin (HBD)-1 and its 5' untranslated region in nonsegmental vitiligo. METHODS: In total, 354 participants [171 patients with non-segmental vitiligo and 183 age and sex-matched healthy controls (HCs)], were genotyped by the PCR-restriction fragment length polymorphism (RFLP) method. For 80 of these individuals (40 patients and -40 HCs) serum HBD-1 was also measured by ELISA. RESULTS: The -44 G allele, CG genotype and GGG haplotype increased the risk for vitiligo (P < 0.02 in all cases), whereas the -20 AA genotype seems to be protective (P = 0.04). Serum HBD-1 levels were lower in patients with vitiligo than in HCs (P < 0.01), as well as in patients with active vitiligo compared with those with stable vitiligo and with HCs (P < 0.05 in both cases), CONCLUSION: Our results suggest that HBD-1 and its gene polymorphisms may modulate vitiligo susceptibility and/or disease activity. This is the first report, to our knowledge, of the association of serum HBD-1 levels and DEFB1 gene polymorphisms with vitiligo.
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Estudios de Asociación Genética/métodos , Polimorfismo de Nucleótido Simple , Vitíligo/genética , beta-Defensinas/genética , Regiones no Traducidas 5' , Adolescente , Adulto , Edad de Inicio , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Haplotipos , Humanos , Masculino , Polimorfismo de Longitud del Fragmento de Restricción , Índice de Severidad de la Enfermedad , Vitíligo/sangre , Adulto Joven , beta-Defensinas/sangreRESUMEN
Food consumers and industries urged the need of natural alternatives to assure food safety and quality. As a response, the use of natural compounds from herbs and spices is an alternative to synthetic additives associated with toxic problems. This review discusses the antimicrobial and antioxidant activity of oregano essential oil (OEO) and its potential as a food additive. Oregano is a plant that has been used as a food seasoning since ancient times. The common name of oregano is given to several species: Origanum (family: Lamiaceae) and Lippia (family: Verbenaceae), amongst others. The main compounds identified in the different OEOs are carvacrol and thymol, which are responsible for the characteristic odor, antimicrobial, and antioxidant activity; however, their content may vary according to the species, harvesting season, and geographical sources. These substances as antibacterial agents make the cell membrane permeable due to its impregnation in the hydrophobic domains, this effect is higher against gram positive bacteria. In addition, the OEO has antioxidant properties effective in retarding the process of lipid peroxidation in fatty foods, and scavenging free radicals. In this perspective, the present review analyzes and discusses the state of the art about the actual and potential uses of OEO as an antimicrobial and antioxidant food additives.
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Antiinfecciosos/análisis , Antioxidantes/análisis , Aceites Volátiles/análisis , Origanum/química , Aceites de Plantas/análisis , Aditivos Alimentarios/análisis , Análisis de los Alimentos , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Conservación de Alimentos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Odorantes/análisis , GustoRESUMEN
Rheumatoid arthritis (RA) is one of the most important rheumatic diseases. Its prevalence varies among ethnic groups. Genetic and environmental factors influence its incidence and prevalence. This chronic disease will increase its frequency in the future due to population aging. The personal impact of this disease on many relevant areas of an individual requires special efforts to prevent and treat it properly. Adequate advice on several recently described risk factors such as tobacco and alcohol exposure, infections, obesity, and physical exercise should be part of every medical consultation. This knowledge should be incorporated to improve health care prevention programs. Patients and clinicians must work together through better communication skills to finally improve outcomes. Including RA in priority health care lists will need special effort from rheumatology societies and better communication with policy makers.
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Envejecimiento , Artritis Reumatoide/epidemiología , Costo de Enfermedad , Artritis Reumatoide/economía , Humanos , Incidencia , América Latina , Factores de RiesgoRESUMEN
OBJECTIVE: To examine the characteristics of patients who developed late onset systemic lupus erythematosus (SLE) in the GLADEL (Grupo Latino Americano de Estudio del Lupus) cohort of patients with SLE. METHODS: Patients with SLE of less than two years of disease duration, seen at 34 centers of nine Latin American countries, were included. Late-onset was defined as >50 years of age at time of first SLE-related symptom. Clinical and laboratory manifestations, activity index (SLEDAI), and damage index (SLICC/ACR- DI) were ascertained at time of entry and during the course (cumulative incidence). Features were compared between the two patient groups (<50 and ≥50) using descriptive statistics and hypothesis tests. Logistic regression was performed to examine the association of late-onset lupus, adjusting for other variables. RESULTS: Of the 1480 patients included, 102 patients (6.9 %) had late-onset SLE, 87% of which were female. Patients with late-onset SLE had a shorter follow-up (3.6 vs. 4.4 years, p < 0.002) and a longer time to diagnosis (10.1 vs. 5.8 months, p < 0.001) compared to the younger onset group. Malar rash, photosensitivity, and renal involvement were less prevalent while interstitial lung disease, pleural effusions, and sicca symptoms were more frequent in the older age group (p > 0.05). In multivariable analysis, late onset was independently associated with higher odds of ocular (OR = 3.66, 95% CI = 2.15-6.23), pulmonary (OR = 2.04, 95% CI = 1.01-4.11), and cardiovascular (OR = 1.76, 95% CI = 1.04-2.98) involvement and lower odds of cutaneous involvement (OR = 0.41, 95% CI = 0.21-0.80), number of cumulative SLE criteria (OR = 0.79, 95% CI = 0.64-0.97), use of cyclophosphamide (OR = 0.47, 95% CI = 0.24-0.95), and anti-RNP antibodies (OR = 0.43, 95% CI = 0.20-0.91). A Cox regression model revealed a higher risk of dying in older onset than the younger-onset SLE (OR = 2.61, 95% CI = 1.2-5.6). CONCLUSION: Late-onset SLE in Latin Americans had a distinct disease expression compared to the younger-onset group. The disease seems to be mild with lower cumulative SLE criteria, reduced renal/mucocutaneous involvements, and less use of cyclophosphamide. Nevertheless, these patients have a higher risk of death and of ocular, pulmonary, and cardiovascular involvements.
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Ciclofosfamida/uso terapéutico , Inmunosupresores/uso terapéutico , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/etnología , Adolescente , Adulto , Edad de Inicio , Anciano , Femenino , Hispánicos o Latinos , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
HIV-1-infected subjects, despite control of viral replication with ART, have an altered immune cytokine/chemokine milieu. Changes in systemic cytokines and chemokines can alter immune responses. IP-10, in particular, has been associated with pathogenesis in a number of conditions, and we found that IP-10 is increased in serum in subjects who are HIV-1 infected and on stable ART compared with HIV-1-uninfected individuals. In a series of in vitro studies, we found that PBMCs exposed to IP-10 showed a significant decrease in the number of cells capable of secreting IFN-γ, as well as other cytokines, when stimulated with recall antigens. Furthermore, treatment with IP-10 led to decreased antigen-specific calcium signaling and MAPK38 phosphorylation. Importantly, the cytokines, as well as proliferative responses, could be enhanced with an IP-10 Nab. Our findings suggest that IP-10-modulating drugs may potentially enhance T cell responses to vaccination and HIV-1 in HIV+ subjects on ART.
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Quimiocina CXCL10/sangre , Infecciones por VIH/inmunología , VIH-1 , Linfocitos T/inmunología , Adulto , Fármacos Anti-VIH/uso terapéutico , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/farmacología , Antígenos/inmunología , Señalización del Calcio/efectos de los fármacos , Células Cultivadas , Quimiocina CXCL10/antagonistas & inhibidores , Quimiocina CXCL10/inmunología , Quimiocina CXCL10/farmacología , Quimiocina CXCL10/fisiología , Citocinas/biosíntesis , Citocinas/sangre , Citotoxicidad Inmunológica , Infecciones por VIH/sangre , Infecciones por VIH/tratamiento farmacológico , Antígenos HLA/biosíntesis , Humanos , Ensayos de Liberación de Interferón gamma , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Activación de Linfocitos , Persona de Mediana Edad , Fosforilación , Procesamiento Proteico-Postraduccional , Receptores CXCR3/metabolismo , Proteínas Recombinantes/farmacología , Linfocitos T/efectos de los fármacos , Adulto Joven , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Immunologic and genetic factors are involved in HIV-1/AIDS pathogenesis. Defensins are key molecules in innate immunity that participate in the control and/or development of infection and disease. Using PCR-RFLPs, we determined the association between HIV-1/AIDS and human ß-defensin 1 (DEFB1) 5'UTR -52 G/A (rs1799946), -44 C/G (rs1800972), and -20 G/A (rs11362) polymorphisms in three groups of women from the state of Sinaloa, located in the Northwest region of Mexico: i) healthy blood donors; ii) sex-workers; and iii) HIV-1 patients. The -52GG genotype was more frequent in blood donors than in patients (p= 0.023; Odds Ratio, OR= 0.49; 95% CI= 0.25-0.95), whereas the - 52GA genotype was significantly higher in patients (p= 0.013; OR= 2.03; 95% CI= 1.11-3.79, statistical power SP= 98.8%), as well as the frequencies of -20A allele (p= 0.017; OR= 1.60; 95% CI= 1.06-2.40), -20AA genotype (p= 0.047; OR = 2.02; 95% CI= 0.93-4.33) and the ACA haplotype with respect to healthy blood donors (p= 0.000012; OR= 5.82; 95% CI= 2.33-16.43, SP= 99.89%) and sex-workers (p= 0.019; OR= 2.18; 95% CI= 1.07-4.46). Conversely, the ACG haplotype was higher in healthy blood donors than in patients (p= 0.009; OR= 0.55; 95% CI= 0.34-0.89). In addition, the -44CC genotype was associated with a low plasma viral load (p= 0.015), whereas AGA, AGG and GGA haplotypes were more prevalent in individuals with high CD4 counts (p= 0.004, 0.046, and 0.029, respectively). These findings associate DEFB1 5'UTR polymorphisms with HIV-1/AIDS in Mexican women for the first time.
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Regiones no Traducidas 5' , Predisposición Genética a la Enfermedad , Infecciones por VIH/epidemiología , Infecciones por VIH/genética , VIH-1/aislamiento & purificación , Polimorfismo Genético , beta-Defensinas/genética , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Genotipo , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , México , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Medición de Riesgo , Adulto JovenAsunto(s)
Hepatitis Autoinmune/epidemiología , Hepatitis Autoinmune/patología , Cirrosis Hepática Biliar/epidemiología , Cirrosis Hepática Biliar/patología , Lupus Eritematoso Sistémico/epidemiología , Lupus Eritematoso Sistémico/patología , Biomarcadores , Biopsia , Comorbilidad , Femenino , Hepatitis Autoinmune/inmunología , Hepatitis Autoinmune/fisiopatología , Humanos , Hígado/patología , Cirrosis Hepática Biliar/inmunología , Cirrosis Hepática Biliar/fisiopatología , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/fisiopatología , Persona de Mediana Edad , Literatura de Revisión como AsuntoRESUMEN
The aims of this study were to describe the clinical features of patients with systemic lupus erythematosus (SLE) who developed cryptococcal infection and ascertain their outcomes when treated with glucocorticoids and immunosuppressive agents in conjunction with long-term maintenance antifungal therapy. Six cases of cryptococcal infection in SLE were reviewed retrospectively. The mean age at the time of infection was 26.3 (11.7) years. Three patients had active SLE and all were receiving glucocorticoids [median prednisone dose of 40 (21.2-60.0) mg/day] at the time of infection diagnosis. Concomitant cytotoxic agents were used in five patients. Meningitis was the most common clinical manifestation (n = 5) and cryptococcemia was found in three cases. The patient, who developed pulmonary cryptococcosis, died from respiratory distress syndrome. All patients received induction anti-fungal therapy with amphotericin B and the five surviving patients switched to oral fluconazole indefinitely as maintenance therapy and none of them has had relapses of cryptococcal infection to last medical evaluation. As SLE patients have intrinsic abnormalities of cell-mediated immunity and receive immunosuppressive therapy, indefinite maintenance therapy with fluconazole is recommended in SLE patients with cryptococcosis.
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Criptococosis/etiología , Lupus Eritematoso Sistémico/complicaciones , Adolescente , Adulto , Criptococosis/diagnóstico , Femenino , Humanos , Masculino , Estudios Retrospectivos , Adulto JovenRESUMEN
We have previously developed and validated a self-administered questionnaire, modelled after the Systemic Lupus International Collaborating Clinics Damage Index (SDI), the Lupus Damage Index Questionnaire (LDIQ), which may allow the ascertainment of this construct in systemic lupus erythematosus (SLE) patients followed in the community and thus expand observations made about damage. We have now translated, back-translated and adapted the LDIQ to Spanish, Portuguese and French and applied it to patients followed at academic and non-academic centres in North and South America, Portugal and Spain while their physicians scored the SDI. A total of 887 patients (659 Spanish-speaking, 140 Portuguese-speaking and 80 French-speaking patients) and 40 physicians participated. Overall, patients scored all LDIQ versions higher than their physicians (total score and all domains). Infrequent manifestations had less optimal clinimetric properties but overall agreement was more than 95% for the majority of items. Higher correlations were observed among the Spanish-speaking patients than the Portuguese-speaking and French-speaking patients; further adjustments may be needed before the Portuguese and French versions of the LDIQ are applied in community-based studies. The relationship between the LDIQ and other outcome parameters is currently being investigated in a different patient sample.
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Lenguaje , Lupus Eritematoso Sistémico , Encuestas y Cuestionarios , Adulto , Femenino , Encuestas Epidemiológicas , Humanos , Lupus Eritematoso Sistémico/patología , Lupus Eritematoso Sistémico/fisiopatología , América del Norte , Portugal , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , América del Sur , España , Encuestas y Cuestionarios/normasRESUMEN
Different immunological alterations may condition systemic lupus erythematosus (SLE) activity. However, it is not known whether alterations in the phenotype of circulating antigen-presenting cells (APCs) and in the response to CpG oligodeoxynucleotides (ODN-CpG) correlate with disease activity. APC expression of HLA-DR, costimulatory molecules, and TLR9 expression was determined in patients with SLE, other autoimmune diseases, and healthy controls. Monocyte and B cell response to synthetic ODN-CpG sequences was also evaluated. Monocytes from patients with moderate SLE activity had higher expression of CD40 and CD86. Decreased numbers of CD19+CD80+ and BDCA-3+CD40+ cells were found in patients with severe SLE activity. In patients with moderate SLE activity, non-adherent and enriched B cell response to ODN-CpG was similar to healthy controls. Adherent and enriched B cells from patients with severe SLE activity did not increase costimulatory molecule expression or cytokine production after ODN-CpG stimulation. APCs from patients with SLE, regardless of disease activity, displayed higher percentage of TLR9+ cells, as well as increased expression of TLR9, compared to healthy controls. Results suggest that the B cell response to ODN-CpG correlates with the SLE activity, independently of TLR9 expression, indicating that alterations in B cell response in severe activity SLE may be caused by events down-stream to TLR9.
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Adyuvantes Inmunológicos , Lupus Eritematoso Sistémico , Oligodesoxirribonucleótidos/inmunología , Adolescente , Adulto , Anciano , Antígenos CD/inmunología , Antígenos de Superficie/inmunología , Células Dendríticas/inmunología , Femenino , Antígenos HLA-DR/inmunología , Humanos , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/fisiopatología , Masculino , Persona de Mediana Edad , Monocitos/inmunología , Trombomodulina , Receptor Toll-Like 9/inmunología , Adulto JovenRESUMEN
The effect of endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide), an organochlorine pesticide, was evaluated on phagocytic (phagocytic index and percentage of active cells) and hematological parameters in Nile tilapia. Experimental data showed that an acute exposure to endosulfan (4.0 and 7.0 microg/L) induces a significant decrease in the phagocytic index and the percentage of active cells in peripherical blood of Nile tilapia. However, hemoglobin concentration (Hb), hematocrit (Hto), red blood cell count (RBC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were not significantly altered in fish exposed to endosulfan compared with control group.
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Células Sanguíneas/efectos de los fármacos , Endosulfano/toxicidad , Insecticidas/toxicidad , Fagocitosis/efectos de los fármacos , Animales , CíclidosRESUMEN
Mexicain is a 23.8 kDa cysteine protease from the tropical plant Jacaratia mexicana. It is isolated as the most abundant product after cation-exchange chromatography of the mix of proteases extracted from the latex of the fruit. The purified enzyme inhibited with E-64 [N-(3-carboxyoxirane-2-carbonyl)-leucyl-amino(4-guanido)butane] was crystallized by sitting-drop vapour diffusion and the structure was solved by molecular replacement at 2.1 A resolution and refined to an R factor of 17.7% (R(free) = 23.8%). The enzyme belongs to the alpha+beta class of proteins and the structure shows the typical papain-like fold composed of two domains, the alpha-helix-rich (L) domain and the beta-barrel-like (R) domain, separated by a groove containing the active site formed by residues Cys25 and His159, one from each domain. The four monomers in the asymmetric unit show one E-64 molecule covalently bound to Cys25 in the active site and differences have been found in the placement of E-64 in each monomer.
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Papaína/química , Secuencia de Aminoácidos , Sitios de Unión , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Cristalización , Cristalografía , Electroforesis en Gel de Poliacrilamida , Enlace de Hidrógeno , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Molecular , Homología de Secuencia de AminoácidoRESUMEN
Mexicain is a 23.7 kDa papain-like cysteine protease from the tropical plant Jacaratia mexicana. Extracted as a mix of proteases from the latex of the fruit, mexicain is isolated after cation-exchange chromatography as the most abundant product. The purified product inhibited with E-64 was crystallized by sitting-drop vapour diffusion in the presence of ethanolamine. Cryoprotected crystals diffracted X-rays from a home source to 1.98 A and belong to the monoclinic space group P2(1), with unit-cell parameters a = 57.36, b = 90.45, c = 80.39 A, beta = 92.64 degrees . The asymmetric unit contains four molecules of mexicain, with a corresponding crystal volume per protein weight (V(M)) of 2.24 A(3) Da(-1) and a solvent content of 45% by volume. A molecular-replacement model has been determined and refinement is in progress.
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Caricaceae/enzimología , Cisteína Endopeptidasas/química , Proteínas de Plantas/química , Cristalización , Cristalografía por Rayos X , Cisteína Endopeptidasas/aislamiento & purificación , Proteínas de Plantas/aislamiento & purificaciónRESUMEN
Concanavalin A has been crystallized in the presence of the ligand (6-S-beta-D-galactopyranosyl-6-thio)-cyclomaltoheptaose. The crystals are isomorphous to those reported for ConA complexed with peptides at low resolution (3.00-2.75 angstroms). The structure was solved at 1.9 angstroms, with free R and R values of 0.201 and 0.184, respectively. As expected, no molecules of the ligand were bound to the protein. Soaking in the cryobuffer left its fingerprint as 25 molecules of glycerol in the bound solvent, most of them at specific positions. The fact that a glycerol molecule is located in the sugar-binding pocket of each of the four subunits in the asymmetric unit and another is located in two of the peptide-binding sites suggests a recognition phenomenon rather than a displacement of water molecules by glycerol. Crystal contact analysis shows that a relation exists between the residues that form hydrogen bonds to other asymmetric units and the space group: contact Asp58-Ser62 is a universal feature of ConA crystals, while Ser66-His121, Asn69-Asn118 and Tyr100-His205 contacts are general features of the C222(1) crystal form.
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Concanavalina A/química , Cristalografía por Rayos X/métodos , Ciclodextrinas/química , Azidas/química , Sitios de Unión , Carbohidratos/química , Portadores de Fármacos , Glicerol/química , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Iones , Manganeso/química , Modelos Moleculares , Conformación Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de ProteínaRESUMEN
The structure of the type II dehydroquinate dehydratase (DHQase) from Actinobacillus pleuropneumoniae, the third enzyme of the shikimate pathway, has been determined. Crystals diffracting to 1.7 A were obtained in space and on earth using the counter-diffusion technique. The structure was solved using molecular replacement and refined to high resolution. The overall structure of the dodecameric enzyme is described and compared with structures of DHQases from other bacteria. DHQases contain a flexible loop that presumably closes over the active site upon substrate binding. The enzyme can exist in an open or closed conformation. The present structure displays the open conformation, with a sulfate anion bound in the active site. The availability of this structure opens a route to structure-based antibiotics targetting this pathogenic bacterium.
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Actinobacillus pleuropneumoniae/enzimología , Proteínas Bacterianas/química , Dominio Catalítico , Hidroliasas/química , Hidroliasas/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Cristalografía por Rayos X , Humanos , Datos de Secuencia Molecular , Estructura Cuaternaria de Proteína , Alineación de SecuenciaRESUMEN
The paper describes a case of cutaneous myiasis caused by the larvae of Hypoderma bovis. Its prolonged recurrent course over 4 months was observed. It appeared as migrating mass lesions, toxicoallergic reactions, and syncope. The paper is the first to show it possible to perform chemotherapy of myiasis with the antibiotic ivermectin in combination with aversectin ointment.
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Mordeduras y Picaduras de Insectos , Insectos , Ivermectina/análogos & derivados , Larva Migrans/parasitología , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades de la Piel/parasitología , Adulto , Animales , Antihelmínticos/uso terapéutico , Antinematodos/uso terapéutico , Femenino , Humanos , Ivermectina/uso terapéutico , Enfermedades de la Piel/complicaciones , Síncope/etiologíaRESUMEN
Protein crystals crack when they are soaked in a solution with ionic strength sufficiently different from the environment in which they grew. It is demonstrated for the case of tetragonal lysozyme that the forces involved and the mechanisms that lead to the formation of cracks are different for hypertonic and hypotonic soaking. Tetragonal lysozyme crystals are very sensitive to hypotonic shocks and, after a certain waiting time, cracks always appear with a characteristic pattern perpendicular to the crystallographic c axis. Conversely, a hypertonic shock is better withstood: cracks do not display any deterministic pattern, are only visible at higher differences in ionic strength and after a certain time a phenomenon of crystal reconstruction occurs and the cracks vanish. At the lattice level, the unit-cell volume expands in hypotonic shock and shrinks under hypertonic conditions. However, the compression of the unit cell is anisotropic: the c axis is compressed to a minimum, beyond which it expands despite the unit-cell volume continuing to shrink. This behaviour is a direct consequence of the positive charge that the crystals bear and the existence of channels along the crystallographic c axis. Both features are responsible for the Gibbs-Donnan effect which limits the free exchange of ions and affects the movement of water inside the channels and bound to the protein.