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1.
Rev Gastroenterol Peru ; 42(4): 251-256, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-36746466

RESUMO

BACKGROUND: Eosinophilic duodenitis has a prevalence of 5.1 to 8.2 per 100000 persons. The underlying molecular mechanisms are unknown, but hypersensitivity (seasonal and food allergies, asthma, eczema) response plays a major role in its pathogenesis, allergic predisposition can be found up-to 25-35% of cases. The diagnosis includes clinical manifestation, imaging findings and histological evidence of eosinophilic infiltration >20 eosinophils per high-power field. This is a clinical case report. a 25-years old man with vitiligo consult to emergency department referring dyspepsia symptoms, vomiting and abdominal pain of maximal intensity, in the medical exam upper abdominal pain was found, blood laboratories were unremarkable except a high net eosinophil-count >2000 cells/ul, abdominal ultrasound were normal, upper endoscopy revealed duodenitis with rigid and thickened folds, colonoscopy show hemorrhoids grade I. Coproscopy exam was negative for parasites, total IgE, IgA and IgG were in normal range, a positive IgG to Toxoplasma gondii was reported, autoimmunity panel was negative. In the following 4 days the abdominal pain and eosinophils count increase, a new abdomin-pelvic tomography was done showing thickened duodenum with a new endoscopy showing marked edema in duodenum with severe biliary reflux with biopsies describing an atrophic chronic duodenitis. Allergy tests -skin prick and patch tests- were done resulting positive to cereals (rye, soy, barley), Manihot esculenta, green banana, tomato, cow milk, orange and pineapple. A restrictive diet and protons pump inhibitor was indicated, ambulatory control at 45 days after show symptoms resolution with a normal blood eosinophils count. Here is reported a case of eosinophilic duodenitis related to food allergy in a young man with vitiligo debuting with an unusual clinical presentation of acute visceral pain and biliary reflux which resolved with elimination diet and pantoprazole without use of corticoids, with both, IgE and non-IgE mechanisms playing important roles explaining food sensitization.


Assuntos
Duodenite , Hipersensibilidade Alimentar , Dor Visceral , Vitiligo , Feminino , Animais , Bovinos , Humanos , Duodenite/complicações , Duodenite/diagnóstico , Vitiligo/complicações , Dor Visceral/complicações , Hipersensibilidade Alimentar/complicações , Hipersensibilidade Alimentar/diagnóstico , Alérgenos , Dor Abdominal/etiologia , Imunoglobulina G
2.
Langmuir ; 32(34): 8660-7, 2016 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-27490089

RESUMO

While nonspecific adsorption is widely used for immobilizing proteins on solid surfaces, the random nature of protein adsorption may reduce the activity of immobilized proteins due to occlusion of the active site. We hypothesized that the orientation a protein assumes on a given surface can be controlled by systematically introducing mutations into a region distant from its active site, thereby retaining activity of the immobilized protein. To test this hypothesis, we generated a combinatorial protein library by randomizing six targeted residues in a binding protein derived from highly stable, nonimmunoglobulin Sso7d scaffold; mutations were targeted in a region that is distant from the binding site. This library was screened to isolate binders that retain binding to its cognate target (chicken immunoglobulin Y, cIgY) as well as exhibit adsorption on unmodified silica at pH 7.4 and high ionic strength conditions. A single mutant, Sso7d-2B5, was selected for further characterization. Sso7d-2B5 retained binding to cIgY with an apparent dissociation constant similar to that of the parent protein; both mutant and parent proteins saturated the surface of silica with similar densities. Strikingly, however, silica beads coated with Sso7d-2B5 could achieve up to 7-fold higher capture of cIgY than beads coated with the parent protein. These results strongly suggest that mutations introduced in Sso7d-2B5 alter its orientation relative to the parent protein, when adsorbed on silica surfaces. Our approach also provides a generalizable strategy for introducing mutations in proteins so as to improve their activity upon immobilization, and has direct relevance to development of protein-based biosensors and biocatalysts.


Assuntos
Proteínas Imobilizadas/química , Proteínas Imobilizadas/genética , Adsorção , Animais , Proteínas Arqueais/química , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Sítios de Ligação , Galinhas , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Imobilizadas/metabolismo , Imunoglobulinas/metabolismo , Cinética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Biblioteca de Peptídeos , Ligação Proteica , Dióxido de Silício , Propriedades de Superfície
4.
BMC Public Health ; 14: 642, 2014 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-24962128

RESUMO

BACKGROUND: Worldwide, acute gastroenteritis causes substantial morbidity and mortality in children less than five years of age. In Bolivia, which has one of the lower GDPs in South America, 16% of child deaths can be attributed to diarrhea, and the costs associated with diarrhea can weigh heavily on patient families. To address this need, the study goal was to identify predictors of cost burden (diarrhea-related costs incurred as a percentage of annual income) and catastrophic cost (cost burden ≥ 1% of annual household income). METHODS: From 2007 to 2009, researchers interviewed caregivers (n = 1,107) of pediatric patients (<5 years old) seeking treatment for diarrhea in six Bolivian hospitals. Caregivers were surveyed on demographics, clinical symptoms, direct (e.g. medication, consult fees), and indirect (e.g. lost wages) costs. Multivariate regression models (n = 551) were used to assess relationships of covariates to the outcomes of cost burden (linear model) and catastrophic cost (logistic model). RESULTS: We determined that cost burden and catastrophic cost shared the same significant (p < 0.05) predictors. In the logistic model that also controlled for child sex, child age, household size, rural residence, transportations taken to the current visit, whether the child presented with complications, and whether this was the child's first episode of diarrhea, significant predictors of catastrophic cost included outpatient status (OR 0.16, 95% CI [0.07, 0.37]); seeking care at a private hospital (OR 4.12, 95% CI [2.30, 7.41]); having previously sought treatment for this diarrheal episode (OR 3.92, 95% CI [1.64, 9.35]); and the number of days the child had diarrhea prior to the current visit (OR 1.14, 95% CI [1.05, 1.24]). CONCLUSIONS: Our analysis highlights the economic impact of pediatric diarrhea from the familial perspective and provides insight into potential areas of intervention to reduce associated economic burden.


Assuntos
Efeitos Psicossociais da Doença , Diarreia/economia , Família , Gastroenterite/economia , Gastos em Saúde , Pobreza , Adolescente , Adulto , Bolívia , Cuidadores , Pré-Escolar , Estudos Transversais , Países em Desenvolvimento , Feminino , Hospitalização , Humanos , Renda , Lactente , Modelos Logísticos , Masculino , Razão de Chances , População Rural , Adulto Jovem
5.
ACS Nano ; 18(12): 8733-8744, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38469811

RESUMO

Covalent conjugation of poly(ethylene glycol) (PEG) is frequently employed to enhance the pharmacokinetics and biodistribution of various protein and nanoparticle therapeutics. Unfortunately, some PEGylated drugs can induce elevated levels of antibodies that can bind PEG, i.e., anti-PEG antibodies (APA), in some patients. APA in turn can reduce the efficacy and increase the risks of allergic reactions, including anaphylaxis. There is currently no intervention available in the clinic that specifically mitigates allergic reactions to PEGylated drugs without the use of broad immunosuppression. We previously showed that infusion of high molecular weight free PEG could safely and effectively suppress the induction of APA in mice and restore prolonged circulation of various PEGylated therapeutics. Here, we explored the effectiveness of free PEG as a prophylaxis against anaphylaxis induced by PEG-specific allergic reactions in swine. Injection of PEG-liposomes (PL) resulted in anaphylactoid shock (pseudoanaphylaxis) within 1-3 min in both naïve and PL-sensitized swine. In contrast, repeated injection of free PEG alone did not result in allergic reactions, and injection of free PEG effectively suppressed allergic reactions to PL, including in previously PL-sensitized swine. These results strongly support the further investigation of free PEG for reducing APA and allergic responses to PEGylated therapeutics.


Assuntos
Anafilaxia , Humanos , Animais , Suínos , Camundongos , Anafilaxia/induzido quimicamente , Anafilaxia/tratamento farmacológico , Anafilaxia/prevenção & controle , Distribuição Tecidual , Nanomedicina , Polietilenoglicóis/farmacologia , Anticorpos/metabolismo , Lipossomos/farmacologia
6.
Pediatr Emerg Care ; 28(6): 493-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22653461

RESUMO

OBJECTIVES: The aim of this study was to analyze the value of performing laboratory tests, taking cultures, and imaging, a diagnostic approach for febrile seizures (FSs) still routinely performed despite the American Academy of Pediatrics recommendations not to. Another aim of this study was to identify the most common sources of fever in patients with FSs and to determine whether the occurrence of FSs correlates with the seasons of the year. METHODS: This is a retrospective study that included all patients diagnosed with simple or complex FSs who were seen in the emergency room or inpatient unit from January 2004 to December 2009. RESULTS: Of the 219 patients included in the study, 135 (61.4%) cases had the etiology of the FS diagnosed. Upper respiratory tract infection, otitis media, urinary infection, and pneumonia were the most common diagnoses attributed to the fever. Leukocytosis was present in 48 (24%) of 219, and neutrophilia in 199 (91%) of 219 cases. Low bicarbonate levels were common among every age group. Only 1 blood culture was positive for Salmonella. The incidence of FS was higher during the winter (49.3% of the cases), and it closely paralleled the seasonal variation of viral infections. CONCLUSIONS: Even though laboratory tests, taking cultures, and imaging are performed in daily practice when approaching FSs, the association of FSs with serious infectious disease is rare and usually overestimated. The diagnostic approach should be individualized to each case and correlated with available data like that shown in this study. Parents should be educated with the knowledge that the occurrence of FSs tends to be higher in winter.


Assuntos
Técnicas de Laboratório Clínico/estatística & dados numéricos , Diagnóstico por Imagem/estatística & dados numéricos , Fidelidade a Diretrizes , Padrões de Prática Médica , Convulsões Febris/diagnóstico , Distribuição por Idade , Pré-Escolar , Medicina Defensiva , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Cidade de Nova Iorque/epidemiologia , Estudos Retrospectivos , Estações do Ano , Convulsões Febris/epidemiologia , Convulsões Febris/etiologia
7.
ACS Omega ; 7(28): 24551-24560, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35874239

RESUMO

The use of immunodetection assays including the widely used enzyme-linked immunosorbent assay (ELISA) in applications such as point-of-care detection is often limited by the need for protein immobilization and multiple binding and washing steps. Here, we describe an experimental and analytical framework for the development of simple and modular "mix-and-read" enzymatic complementation assays based on split luciferase that enable sensitive detection and quantification of analytes in solution. In this assay, two engineered protein binders targeting nonoverlapping epitopes on the target analyte were each fused to nonactive fragments of luciferase to create biosensor probes. Binding proteins to two model targets, lysozyme and Sso6904, were isolated from a combinatorial library of Sso7d mutants using yeast surface display. In the presence of the analyte, probes were brought into close proximity, reconstituting enzymatic activity of luciferase and enabling detection of low picomolar concentrations of the analyte by chemiluminescence. Subsequently, we constructed an equilibrium binding model that relates binding affinities of the binding proteins for the target, assay parameters such as the concentrations of probes used, and assay performance (limit of detection and concentration range over which the target can be quantified). Overall, our experimental and analytical framework provides the foundation for the development of split luciferase assays for detection and quantification of various targets.

8.
Adv Drug Deliv Rev ; 169: 100-117, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33309815

RESUMO

To address the COVID-19 pandemic, there has been an unprecedented global effort to advance potent neutralizing mAbs against SARS-CoV-2 as therapeutics. However, historical efforts to advance antiviral monoclonal antibodies (mAbs) for the treatment of other respiratory infections have been met with categorical failures in the clinic. By investigating the mechanism by which SARS-CoV-2 and similar viruses spread within the lung, along with available biodistribution data for systemically injected mAb, we highlight the challenges faced by current antiviral mAbs for COVID-19. We summarize some of the leading mAbs currently in development, and present the evidence supporting inhaled delivery of antiviral mAb as an early intervention against COVID-19 that could prevent important pulmonary morbidities associated with the infection.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antivirais/uso terapêutico , COVID-19/terapia , Fatores Imunológicos/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Antivirais/química , Antivirais/metabolismo , COVID-19/diagnóstico , COVID-19/metabolismo , Humanos , Imunização Passiva , Fatores Imunológicos/química , Fatores Imunológicos/metabolismo , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , SARS-CoV-2/química , SARS-CoV-2/metabolismo , Eliminação de Partículas Virais/efeitos dos fármacos , Eliminação de Partículas Virais/fisiologia , Soroterapia para COVID-19
9.
Sci Transl Med ; 13(606)2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380769

RESUMO

Many women risk unintended pregnancy because of medical contraindications or dissatisfaction with contraceptive methods, including real and perceived side effects associated with the use of exogenous hormones. We pursued direct vaginal delivery of sperm-binding monoclonal antibodies (mAbs) that can limit progressive sperm motility in the female reproductive tract as a strategy for effective nonhormonal contraception. Here, motivated by the greater agglutination potencies of polyvalent immunoglobulins but the bioprocessing ease and stability of immunoglobulin G (IgG), we engineered a panel of sperm-binding IgGs with 6 to 10 antigen-binding fragments (Fabs), isolated from a healthy immune-infertile woman against a unique surface antigen universally present on human sperm. These highly multivalent IgGs (HM-IgGs) were at least 10- to 16-fold more potent and faster at agglutinating sperm than the parent IgG while preserving the crystallizable fragment (Fc) of IgG that mediates trapping of individual spermatozoa in mucus. The increased potencies translated into effective (>99.9%) reduction of progressively motile sperm in the sheep vagina using as little as 33 µg of the 10-Fab HM-IgG. HM-IgGs were produced at comparable yields and had identical thermal stability to the parent IgG, with greater homogeneity. HM-IgGs represent not only promising biologics for nonhormonal contraception but also a promising platform for engineering potent multivalent mAbs for other biomedical applications.


Assuntos
Imunoglobulina G , Motilidade dos Espermatozoides , Animais , Anticoncepção , Feminino , Humanos , Fragmentos Fab das Imunoglobulinas , Masculino , Gravidez , Ovinos , Espermatozoides
10.
BMC Infect Dis ; 10: 253, 2010 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-20735858

RESUMO

BACKGROUND: Evidence suggests that probiotics reduce rotavirus diarrhoea duration. Although there are several probiotic strains potentially useful, daily practice is often limited by the type and number of products locally available. In general, information about combined products is scarce. In this study we compare the effect of two probiotic products in the treatment of diarrhoea in children less than 2 years of age. METHODS: A Randomized double-blind controlled clinical trial in children hospitalized for acute rotavirus diarrhoea, in the Paediatric Centre Albina Patino, Cochabamba, Bolivia.Participants were children aged 1 - 23 months, who were randomly assigned to receive one of three treatments: Oral rehydration therapy plus placebo; Oral rehydration solution plus Saccharomyces boulardii; or Oral rehydration solution plus a compound containing Lactobacillus acidophilus, Lactobacillus rhamnosus, Bifidobacterium longum and Saccharomyces boulardii. Sample size was 20 per group and the outcomes were duration of diarrhoea, of fever, of vomiting and of hospitalization. RESULTS: 64 cases finished the protocol. On admission, patients' characteristics were similar. Median duration of diarrhoea (p = 0.04) in children who received the single species product (58 hours) was shorter than in controls (84.5 hrs). Comparing children that received the single probiotic product and controls showed shorter duration of fever (18 vs 67 hrs) (p = 0.0042) and the mixed probiotic of vomiting (0 vs 42.5 hrs) (p = 0.041). There was no effect on duration of hospitalization (p = 0.31). When experimental groups were merged, statistical significance of changes increased (total duration of diarrhoea, fever and vomiting P = 0.025, P = 0.025 and P = 0.014, respectively). CONCLUSIONS: Both products decreased the duration of diarrhoea compared to oral rehydration solution alone. This decrease was significant only for the single species product which also decreased the duration of fever. With the multiple species product there was no vomiting subsequent to the initiation of treatment. The quantity of probiotic bacteria needed for optimum treatment of gastroenteritis remains to be determined, particularly when multiple species are included in the product.Trial registration: ClinicalTrials.gov ID: NCT00981877Link: https://register.clinicaltrials.gov/prs/app/action/SelectProtocol/sid/S0002653/selectaction/View/ts/2/uid/U0000N04 TRIAL REGISTRATION: Clinical trials NCT ID: NCT00981877.


Assuntos
Bifidobacterium/crescimento & desenvolvimento , Diarreia/terapia , Gastroenterite/terapia , Lactobacillus/crescimento & desenvolvimento , Probióticos/administração & dosagem , Infecções por Rotavirus/terapia , Saccharomyces/crescimento & desenvolvimento , Bifidobacterium/fisiologia , Bolívia , Diarreia/virologia , Método Duplo-Cego , Feminino , Hidratação , Gastroenterite/virologia , Humanos , Lactente , Lactobacillus/fisiologia , Masculino , Placebos/administração & dosagem , Rotavirus/isolamento & purificação , Saccharomyces/fisiologia , Resultado do Tratamento
11.
Methods Mol Biol ; 2070: 321-334, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31625104

RESUMO

Combinatorial library screening platforms, such as yeast surface display, typically identify several candidate proteins that need further characterization and validation using soluble recombinant protein. However, recombinant production of these candidate proteins involves tedious and time-consuming subcloning steps. This, in turn, limits the number of candidate proteins that can be characterized. To address this bottleneck, we have developed a platform that exploits inefficient ribosomal skipping by the F2A peptide for simultaneous soluble secretion and cell surface display of protein in the yeast Saccharomyces cerevisiae. Here we provide detailed protocols utilizing this F2A-based yeast display system. We discuss specific recommendations for the purification of the secreted protein. Additionally, we provide suggestions for testing the functionality and binding specificity of the soluble secreted proteins using flow cytometry analysis.


Assuntos
Biblioteca de Peptídeos , Peptídeos/metabolismo , Biossíntese de Proteínas , Ribossomos/metabolismo , Saccharomyces cerevisiae , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
12.
J Control Release ; 326: 106-119, 2020 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-32569705

RESUMO

The gut microbiome is a promising target for the development of GI tract therapies, yet it has been under-exploited due, in part, to a lack of tools to control and manipulate complex microbial communities. To date, the most common approach in harnessing bacteria for therapeutic purposes has been to deliver ex vivo engineered bacteria-effectively taking a bacterial cell therapy-based approach. An alternative approach involves taking advantage of the rich microbial ecosystem in the gut by genetically modifying the microbiome in situ through the use of engineered bacteriophages-akin to human gene therapies delivered by viral vectors. In this review, we present the challenges and opportunities associated with engineering bacteriophages to control and manipulate the gut microbiome.


Assuntos
Bacteriófagos , Microbioma Gastrointestinal , Microbiota , Bactérias , Humanos
13.
Med Clin (Barc) ; 131 Suppl 2: 2-9, 2008 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-19087844

RESUMO

The results of epidemiological studies of venous thromboembolic disease (VTD) vary widely, depending both on the geographical area and study type. In Spain, there are no data on the incidence and distribution of VTD. To determine the incidence and distribution of this disease, we analyzed the hospital discharges codified by the Spanish national health system. The results of the analysis showed that VTD represented 0.82% (0.69%-0.92%) of all hospital discharges in Spain between 1999 and 2005. The rate of diagnoses for all hospital discharges in 2005 was 103/100,000 inhabitants, with an estimated number of total diagnoses in Spain (hospitalized or not) of 154/100,000. Fifty-three percent were pulmonary embolisms (PE), which showed a tendency to increase, and 47% were deep venous thrombosis (DVT), which showed a tendency to decrease. The mean age was 65 years in men (51% of cases) and 68 years in women, with the incidence increasing exponentially with age. The mean age in patients with PE was 70 years vs 64 years in DVT. Mortality associated with PE was 11.6% vs 2.3% with DVT. DVT occurred during admission in 4% (3-4.7) of persons hospitalized for any cause, 74% of patients being admitted for medical problems. These data reveal that DVT is a serious health problem in Spain, with high morbidity and mortality. The incidence of this disease seems to be increasing and is particularly associated with medical problems, despite improved diagnosis and the accumulated evidence on thromboprophylaxis. Therefore, greater efforts should be made both to improve identification of at-risk patients and the application of prevention protocols.


Assuntos
Tromboembolia Venosa/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Grupos Diagnósticos Relacionados , Feminino , Hospitalização , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Embolia Pulmonar/epidemiologia , Fatores Sexuais , Espanha/epidemiologia , Trombose Venosa/epidemiologia
14.
Med Clin (Barc) ; 130(15): 568-72, 2008 Apr 26.
Artigo em Espanhol | MEDLINE | ID: mdl-18462633

RESUMO

BACKGROUND AND OBJECTIVE: To analyze the trends in the utilization of ventilation/perfusion pulmonary scintigraphy (V/QSc), spiral CT (sCT) and pulmonary angiography for diagnosis of pulmonary embolism (PE) in Spain, taking in account the information from the National System of Health (NSH) and RIETE Registry. To examine the diagnostic conformities of V/QSc and sCT in RIETE, with special reference to V/QSc of intermediate/indeterminate probability (V/QScIP). MATERIAL AND METHOD: We examined annual trends of diagnostic imaging for PE in 5,678 Spanish patients included in RIETE (period 2001-2005) and in those of the NHS Databases (1999-2003 period). In RIETE the agreement between diagnostics was compared in cases with both V/QSc and sCT and angiography and V/QSc or sCT. RESULTS: We observed an increasing trend in sTC use, which overcame to V/QSc in 2002 (RIETE) and 2003 (NHS). In 732 cases with both techniques there was a diagnostic conformity of 53%. In 116 cases with V/QScIP a concomitant sTC was + for PE in 87%. If clinical signs of PE were present, then sTC was + in 95% of cases. In 29 cases with sCT and angiography agreement was 83% and in 31 cases with angiography and V/QSc was 77%. CONCLUSIONS: Nowadays in Spain the sTC is the most utilized method to diagnose EP. However, V/QSc studies are also broadly used. In studies V/QScIP it is advisable to look for deep venous thrombosis and, if present, the results of RIETE allow to assure EP coexistence in 87-95% of cases.


Assuntos
Embolia Pulmonar/diagnóstico , Tomografia Computadorizada Espiral , Relação Ventilação-Perfusão , Idoso , Feminino , Humanos , Masculino , Sistema de Registros , Espanha
15.
ACS Comb Sci ; 20(10): 579-584, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30188690

RESUMO

Magnetization using cheap and minimally toxic materials, such as iron oxide nanoparticles can enable easy separation of cells from culture medium and is relevant to several industrial applications. Here, we show that cell surface expression of a mutant protein that binds iron oxide can enable efficient magnetization of yeast cells. We screened a combinatorial library of mutants derived from the Sso7d protein scaffold to isolate proteins that exhibit preferential binding to iron oxide. One of the isolated mutants, SsoFe2, was chosen for further characterization. Yeast cells expressing SsoFe2 as fusions to a cell wall protein-but not other Sso7d mutants with similar overall protein charge or amino acid composition-preferentially bind iron oxide when present in a solution with high protein concentration and in the presence of 1000-fold excess of competitor yeast cells. Moreover, coexpression of cell surface SsoFe2 enables efficient magnetic capture and separation of yeast cells expressing an enzyme (glucose oxidase) on the cell surface from yeast culture medium, and solutions with high protein concentration or containing other metal oxides. Therefore, SsoFe2-enabled magnetization can enable a range of industrial and biotechnology applications, where easy separation of cells or organelles from complex media is desirable.


Assuntos
Proteínas Arqueais/metabolismo , Proteínas de Ligação a DNA/metabolismo , Nanopartículas de Magnetita/química , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Proteínas Arqueais/genética , Membrana Celular/metabolismo , Proteínas de Ligação a DNA/genética , Fenômenos Magnéticos , Mutação , Biblioteca de Peptídeos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética
18.
Gac. méd. boliv ; 45(1)2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1385006

RESUMO

Resumen El síndrome de Cook fue descrito por primera vez por Cook y colaboradores en 1985. Este se caracteriza por una historia familiar de hipoplasia congénita de las uñas de las manos en los dígitos 1,2 y 3, ausencia de las uñas en los dígitos 4 y 5, braquidactilia del digito 5 de las manos y ausencia complete de las uñas de los pies. Además, puede existir una hipoplasia o ausencia de las falanges distales en los pies y las manos. La oficina de enfermedades raras del Instituto Nacional de Salud, considera este síndrome como una "enfermedad rara". Presentamos el caso de un recién nacido con anoniquia congénita en ambas manos y pies en el digito 2 asociado a hipoplasia ungueal en dígitos 1 y 3 respetando dígitos 4 y 5. La radiografía de los dedos no muestra anormalidades en las falanges. Este caso podría representar una variante del síndrome de Cook o una nueva enfermedad aun no descrita debido a la existencia de una historia familiar importante con similares deformidades en la madre, la abuela y la hermana.


Abstract Cooks syndrome, which was first reported by Cooks et al in 1985. It is characterized by family history of bilateral congenital nail hypoplasia of digits 1,2 and 3, with absence of nails in digits 4, 5, and brachydactyly of digit five of the hands and complete absence of all toenails. In addition, there is hypoplasia or absence of distal phalanges of the hands and feet. According to the Office of rare Diseases of the National Institutes of Health, this syndrome is considered as a "rare disease". We present a newborn child with a history of congenital anonychia in digit 2 in both hands and feet and nail hypoplasia in digits 1 and 3 sparing digits 4 and 5. Radiography of the fingers shows no abnormalities in the phalanges. This case could represent a variant of Cooks syndrome or a new disease not yet described because of the existence of an important family history with similar deformities in the mother, grandmother and sister.

19.
Rev. gastroenterol. Peru ; 42(4)oct. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1423950

RESUMO

La duodenitis eosinofílica tiene una prevalencia entre 5,1 a 8,2 por 100000 personas. Se desconocen los mecanismos moleculares subyacentes de la enfermedad, pero la hipersensibilidad (alergias estacionales y alimentarias) juega un papel importante en su patogénesis, la predisposición alérgica se encuentra en el 25-35% de los casos. El diagnóstico incluye manifestaciones clínicas, hallazgos imagenológicos y evidencia histológica de infiltración eosinofílica >20 eosinófilos por campo de alto poder. Realizamos un informe de caso clínico y revisión de literatura. Hombre de 25 años con vitíligo que consulta a urgencias refiriendo síntomas de dispepsia, vómitos y dolor abdominal de máxima intensidad, en el examen médico se localiza dolor abdominal superior, con paraclínicos normales excepto un recuento de eosinófilos >2000 células/ul, la ecografía abdominal fue normal, la endoscopia superior reveló pangastritis eritematosa y duodenitis con pliegues rígidos y engrosados, la colonoscopia mostró hemorroides grado I. Coproscópico seriado negativo para parásitos, IgE total, IgA e IgG en rango normal, se reportó IgG positivo a Toxoplasma gondii, perfil de autoinmunidad negativo. En los siguientes 4 días aumenta el dolor abdominal y el recuento de eosinófilos, con endoscopia control y tomografía abdomino-pélvica contrastada que muestran duodeno edematizado con reflujo biliar severo, reporte histopatológico con duodenitis crónica atrófica y con pruebas para alergenos alimentarios positivo a cereales (centeno, soja, cebada), Manihot esculenta, plátano verde, tomate, leche de vaca, naranja y piña. Se indicó dieta restrictiva e inhibidor de la bomba de protones (pantoprazol), control ambulatorio a los 45 días de resolución de los síntomas con recuento de eosinófilos en sangre normal. Se presenta un caso de duodenitis eosinofílica relacionada con alergia alimentaria con mecanismos IgE independientes en un varón joven con vitíligo, que debutó con cuadro clínico inusual de dolor visceral agudo y reflujo biliar, que se resolvió con dieta de eliminación y pantoprazol sin uso de corticoides.


Background: Eosinophilic duodenitis has a prevalence of 5.1 to 8.2 per 100000 persons. The underlying molecular mechanisms are unknown, but hypersensitivity (seasonal and food allergies, asthma, eczema) response plays a major role in its pathogenesis, allergic predisposition can be found up-to 25-35% of cases. The diagnosis includes clinical manifestation, imaging findings and histological evidence of eosinophilic infiltration >20 eosinophils per high-power field. This is a clinical case report. a 25-years old man with vitiligo consult to emergency department referring dyspepsia symptoms, vomiting and abdominal pain of maximal intensity, in the medical exam upper abdominal pain was found, blood laboratories were unremarkable except a high net eosinophil-count >2000 cells/ul, abdominal ultrasound were normal, upper endoscopy revealed duodenitis with rigid and thickened folds, colonoscopy show hemorrhoids grade I. Coproscopy exam was negative for parasites, total IgE, IgA and IgG were in normal range, a positive IgG to Toxoplasma gondii was reported, autoimmunity panel was negative. In the following 4 days the abdominal pain and eosinophils count increase, a new abdomin-pelvic tomography was done showing thickened duodenum with a new endoscopy showing marked edema in duodenum with severe biliary reflux with biopsies describing an atrophic chronic duodenitis. Allergy tests -skin prick and patch tests- were done resulting positive to cereals (rye, soy, barley), Manihot esculenta, green banana, tomato, cow milk, orange and pineapple. A restrictive diet and protons pump inhibitor was indicated, ambulatory control at 45 days after show symptoms resolution with a normal blood eosinophils count. Here is reported a case of eosinophilic duodenitis related to food allergy in a young man with vitiligo debuting with an unusual clinical presentation of acute visceral pain and biliary reflux which resolved with elimination diet and pantoprazole without use of corticoids, with both, IgE and non-IgE mechanisms playing important roles explaining food sensitization.

20.
ACS Synth Biol ; 6(11): 2096-2107, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-28805373

RESUMO

The need for recombinant expression of soluble protein slows the validation of engineered proteins isolated from combinatorial libraries and limits the number of protein variants evaluated. To overcome this bottleneck, we describe a system for simultaneous cell surface display and soluble secretion of proteins in Saccharomyces cerevisiae based on inefficient ribosomal skipping. Ribosomal skipping mediated by "self-cleaving" 2A peptides produces two proteins from a single open reading frame. Incorporation of the F2A peptide sequence-with ∼50% efficiency of ribosomal skipping-between the protein of interest and the yeast cell wall protein Aga2 results in simultaneous expression of both the solubly secreted protein and the protein-Aga2 fusion that is tethered to the yeast cell surface. We show that binding proteins derived from the Sso7d scaffold and the homodimeric enzyme glucose oxidase can be simultaneously secreted solubly and expressed as yeast cell surface fusions using the F2A-based system. Furthermore, a combinatorial library of Sso7d mutants can be screened to isolate binders with higher affinity for a model target (lysozyme), and the pool of higher affinity binders can be characterized in soluble form. Significantly, we show that both N- and C-terminal fusions to Aga2 can be simultaneously secreted solubly and displayed on the cell surface; this is particularly advantageous because protein functionality can be affected by the specific position of Aga2 in the protein fusion. We expect that the F2A-based yeast surface display and secretion system will be a useful tool for protein engineering and enable efficient characterization of individual clones isolated from combinatorial libraries.


Assuntos
Moléculas de Adesão Celular , Expressão Gênica , Biblioteca de Peptídeos , Peptídeos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
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