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1.
Arch Oral Biol ; 164: 105978, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38718465

RESUMO

OBJECTIVE: To evaluate the effect of the association of potassium iodide to antimicrobial photodynamic therapy on human carious dentin produced with a microcosm biofilm model. METHODS: A microcosm biofilm model was used to generate a caries lesion on human dentin. Pooled human saliva diluted with glycerol was used as an inoculum on specimens immersed on McBain artificial saliva enriched with 1 % sucrose (24 h at 37 °C in 5 % CO2). After refreshing culture media for 7 days, the dentin specimens were divided in 5 groups (3 specimens per group, in triplicate; n = 9): C (NaCl 0.9 %), CX (2 % chlorhexidine), PKI (0.01 % methylene blue photosensitizer+50 mM KI), L (laser at 15 J, 180 s, 22.7 J/cm2), and PKIL (methylene blue + KI + Laser). After the treatments, dentin was collected, and a 10-fold serial dilution was performed. The number of total microorganisms, total lactobacilli, total streptococci, and Streptococcus mutans was analyzed by microbial counts (CFU/mL). After normality and homoscedasticity analysis, the Welch's ANOVA and Dunnett's tests were used for CFU. All tests used a 5 % significance level. RESULTS: CX and PKIL groups showed significant bacterial decontamination of dentin, compared to group C (p < 0.05) reaching reductions up to 3.8 log10 for CX for all microorganisms' groups and PKIL showed 0.93, 1.30, 1.45, and 1.22 log10 for total microorganisms, total lactobacilli, total streptococci, and S. mutans, respectively. CONCLUSION: aPDT mediated by the association of KI and methylene blue with red laser reduced the viability of microorganisms from carious dentin and could be a promising option for cavity decontamination.

2.
Patterns (N Y) ; 5(3): 100953, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38487803
3.
Infect Med (Beijing) ; 2(3): 241-245, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38073885

RESUMO

Background: Given that epidemiological evidence suggests a potential protective role for Bacille-Calmette-Guerin against COVID-19, we aimed to explore whether pre-exposure of human monocyte-derived macrophages and dendritic cells to BCG could modulate their response to SARS-CoV-2 S-glycoprotein. Methods: Dual THP-1 cells containing 2 reporter plasmids for transcription factors NF-κB, and IRF were differentiated into macrophages over 3 days using phorbol 12-myristate 13-acetate, or into dendritic cells over 6 days using commercial monocyte-dencritic cell differentiation media and matured with recombinant tumor necrosis factor-α. Cells were exposed to BCG for 24 h and then stimulated with SARS-CoV-2 S-glycoprotein for 24 hours. Results: Pre-exposure of human macrophages and DCs to BCG increased IRF and NF-kb activation in response to the SARS-CoV-2 S-glycoprotein. Conclusions: Our results showed that pre-exposure of both types of cells to BCG exhibited an increase in inflammatory transcription factors upon stimulation with S-glycoprotein. BCG-induced trained immunity may be an important tool for reducing susceptibility to SARS-CoV-2 infection and severity of COVID-19. Our findings help in the design of future BCG-based therapeutic approaches in the treatment of diseases caused by viral infections.

4.
Dolor ; 33(76): 16-22, ago. 2023. ilus
Artigo em Espanhol | LILACS | ID: biblio-1510384

RESUMO

Los sesgos cognitivos son un constructo que acuñaron Kahneman & Tveysky (1972) en su Enfoque de Sesgos dentro de la Psicología Cognitiva. Estos son atajos intelectuales que realizan siempre las personas, desde un razonamiento probabilístico intuitivo. El presente trabajo es una primera aproximación que intenta aplicar y describir algunos sesgos cognitivos en el complejo mundo de las representaciones mentales en la experiencia dolorosa, como la ilusión de control; del presente; la confirmación; representatividad; disponibilidad, entre otros. Los sesgos en dolor nos permiten comprender el procesamiento de información frente al dolor y utilizar estrategias comunicacionales más efectivas para su abordaje.


Cognitive biases are a construct coined by Kahneman & Tveysky (1972) in their Approach to Biases in Cognitive Psychology. These are intellectual shortcuts that people always carry out, from an intuitive probabilistic reasoning. An attempt is made to apply and describe some cognitive biases in the complex world of mental representations in the painful experience, like the illusion of control; of the present; the confirmation; representativeness; availability among others. Biases in pain allow us to understand the processing of information in the face of pain and use more effective communication strategies to address it.


Assuntos
Humanos , Dor Crônica , Psicologia Cognitiva , Pensamento , Viés , Intuição
5.
Liver Transpl ; 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38166123

RESUMO

Disparities exist in pediatric liver transplant (LT). We characterized barriers and facilitators to providing transplant and social care within pediatric LT clinics. This was a multicenter qualitative study. We oversampled caregivers reporting household financial strain, material economic hardship, or demonstrating poor health literacy. We also enrolled transplant team members. We conducted semistructured interviews with participants. Caregiver interviews focused on challenges addressing transplant and household needs. Transplant provider interviews focused on barriers and facilitators to providing social care within transplant teams. Interviews were recorded, transcribed, and coded according to the Capability, Opportunity, Motivation-Behavior model. We interviewed 27 caregivers and 27 transplant team members. Fifty-two percent of caregivers reported a household income <$60,000, and 62% reported financial resource strain. Caregivers reported experiencing (1) high financial burdens after LT, (2) added caregiving labor that compounds the financial burden, (3) dependency on their social network's generosity for financial and logistical support, and (4) additional support being limited to the perioperative period. Transplant providers reported (1) relying on the pretransplant psychosocial assessment for identifying social risks, (2) discomfort initiating social risk discussions in the post-transplant period, (3) reliance on social workers to address new social risks, and (4) social workers feeling overburdened by quantity and quality of the social work referrals. We identified barriers to providing effective social care in pediatric LT, primarily a lack of comfort in assessing and addressing new social risks in the post-transplant period. Addressing these barriers should enhance social care delivery and improve outcomes for these children.

6.
Pathogens ; 11(11)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36422612

RESUMO

Mexico is an endemic region for dengue virus (DENV). The increase in this disease coincides with outbreaks of COVID-19, both of which are single-stranded positive RNA viruses. These characteristics make it difficult to distinguish each disease because they share clinical and laboratory features, which can consequently result in misdiagnoses. This is why the use of precision confirmatory tests (qRT-PCR) are crucial for early diagnosis. We herein report a pediatric patient who presented a coinfection for DENV and COVID-19, "SARS-CoV-2/Dengue". This patient initially presented a fever, cough, and headache and, three days later, developed generalized pain and epistaxis. Blood studies revealed thrombocytopenia and leukopenia, and the patient was admitted to the hospital for a probable DENV infection. Within 48 h, qRT-PCR tests specific for SARS-CoV-2 and DENV were performed and resulted as positive. The patient immediately received pharmacological treatment with azithromycin, oseltamivir, and metamizole. During hospitalization (9 days), the patient had no signs of respiratory distress and maintained normal body temperature and normal blood oxygen saturation. This case warns of the need for early diagnosis and adequate clinical and pharmacological management in the face of a "SARS-CoV-2/Dengue" coinfection. Early molecular detection of both viruses and timely treatment helped the patient to achieve a favorable recovery.

7.
Photodiagnosis Photodyn Ther ; 40: 103123, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36115559

RESUMO

OBJECTIVE: To evaluate the efficacy of methylene blue (MB)-mediated antimicrobial photodynamic therapy (aPDT) doped with potassium iodide (KI) against oral microcosms biofilms cultured in dentin. METHODS: A saliva-glycerol stock formed from pooled human saliva was diluted in McBain artificial saliva with 1% sucrose (1:1), inoculated on bovine dentin blocks, and refreshed daily for 5 days. The biofilms were divided (n = 9/group) and treated with 0.9% NaCl (C), 0.2% chlorhexidine (CX), 0.01% MB + low-power laser 15 J, 88 mW, 180 s (PL), and 0.01% MB + 50 mM KI + laser (PKIL). Serial dilution was performed, and cellular viability (CFU/mL) was evaluated for total microorganisms, total lactobacilli, total streptococci, and S. mutans. Additional biofilms were cultured and treated (n = 4) for biomass determination (%BMR). The microscopic structure of the biofilms was observed by SEM. One-way ANOVA and Tukey tests were conducted (α=5%). RESULTS: Total microorganisms and total streptococci significantly reduced in biofilms treated with CX and PKIL when compared to C, but the CX, PKIL, and PL treatments did not differ from each other. Total lactobacilli and S. mutans showed a significant reduction in the CX, PL, and PKIL groups when compared to C, but with no difference between them. Biomass analysis showed a significantly reduction for CX and PKIL compared to C. SEM micrographs showed noticeable changes in bacterial membrane integrity for the PKIL and CX groups. CONCLUSION: The addition of KI to methylene blue-mediated aPDT in microcosm biofilms was effective in reducing oral microorganisms, but the effect was group dependent.


Assuntos
Anti-Infecciosos , Fotoquimioterapia , Bovinos , Animais , Humanos , Fotoquimioterapia/métodos , Azul de Metileno/farmacologia , Iodeto de Potássio , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Streptococcus mutans , Biofilmes , Anti-Infecciosos/uso terapêutico , Streptococcus , Clorexidina/farmacologia , Lasers
8.
Artigo em Inglês | MEDLINE | ID: mdl-35615950

RESUMO

Summary: We present the case of a 23-year-old patient with maturity-onset diabetes of the young type 3 (MODY 3) and premature ovarian insufficiency (POI). There is no known correlation between MODY 3 and POI, although POI can impair glucose metabolism, and MODY can cause microvascular complications such as POI. We did not find literature describing a correlation between these two pathologies nor did we find similar cases described in the literature. Learning points: Maturity-onset diabetes of the young type 3 (MODY 3) is an infrequent cause of diabetes that should be considered in young patients with atypical presentation of type 1 or type 2 diabetes. MODY 3 can be associated with microvascular complications of diabetes, which is why it is important to diagnose as early as possible. Impairment of glucose metabolism has been demonstrated in patients with premature ovarian insufficiency and menopause.

9.
Photodiagnosis Photodyn Ther ; 37: 102622, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34775066

RESUMO

OBJECTIVE: To evaluate the effect of potassium iodide (KI) addition on antimicrobial photodynamic therapy (aPDT) mediated by red laser (λ = 660 nm) and methylene blue in Streptococcus mutans biofilm model. METHODS: S. mutans biofilms were cultured in 96-well plates containing BHI broth with 1% sucrose for 18 h, 10% CO2 and 37 °C and divided in groups (n = 3, in triplicate): C (NaCl 0.9%); CX (0.2% chlorhexidine); P (photosensitizer); KI (10, 25 and 50 mM); PKI (10, 25 and 50 mM); L (L1: 100 J/cm2, 9 J; L2: 200 J/cm2, 18 J); PL (photosensitizer + L1 or L2); KIL (KI at 10, 25 and 50 mM + L1 or L2); and PKIL (photosensitizer + 10, 25 and 50 mM KI + L1 or L2). Biofilms were submitted to three pre-irradiation (PI) times (5, 10, and 15 min). After the treatments, microbial counting's reduction was analyzed by Kruskal-Wallis and post-hoc Dunn's tests, respectively, and the interaction between light parameters and the PI times by two-way ANOVA (p < 0.05). RESULTS: The S. mutans viability significantly reduced in all aPDT groups, in the presence or absence of KI (p < 0.05). For all PI times, PKIL groups (10, 25, and 50 mM) significantly differed from PL groups (p < 0.05) with a reduction of 9.0 logs reached at 50 mM of KI with 15 min of PI, irradiated at 18 J. We found no significant interaction between PI time and irradiation (p > 0.05). CONCLUSION: The addition of KI to PDT mediated by methylene blue and red laser promoted an additional effect in reducing the microbial viability of S. mutans biofilm.


Assuntos
Anti-Infecciosos , Fotoquimioterapia , Anti-Infecciosos/farmacologia , Biofilmes , Lasers , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Iodeto de Potássio/farmacologia , Streptococcus mutans
10.
Int J Mol Sci ; 22(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34830131

RESUMO

Production of biofuels and other value-added products from lignocellulose breakdown requires the coordinated metabolic activity of varied microorganisms. The increasing global demand for biofuels encourages the development and optimization of production strategies. Optimization in turn requires a thorough understanding of the microbial mechanisms and metabolic pathways behind the formation of each product of interest. Hydrolysis of lignocellulosic biomass is a bottleneck in its industrial use and often affects yield efficiency. The accessibility of the biomass to the microorganisms is the key to the release of sugars that are then taken up as substrates and subsequently transformed into the desired products. While the effects of different metabolic intermediates in the overall production of biofuel and other relevant products have been studied, the role of proteins and their activity under anaerobic conditions has not been widely explored. Shifts in enzyme production may inform the state of the microorganisms involved; thus, acquiring insights into the protein production and enzyme activity could be an effective resource to optimize production strategies. The application of proteomic analysis is currently a promising strategy in this area. This review deals on the aspects of enzymes and proteomics of bioprocesses of biofuels production using lignocellulosic biomass as substrate.


Assuntos
Bactérias Anaeróbias/metabolismo , Biocombustíveis/microbiologia , Biomassa , Lignina/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Anaerobiose , Bactérias Anaeróbias/classificação , Bactérias Anaeróbias/enzimologia , Celulases/metabolismo , Hidrólise , Oxigenases/metabolismo
11.
Acta otorrinolaringol. cir. cuello (En línea) ; 49(1): 57-61, 2021. ilus, tab, graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1152173

RESUMO

Las lesiones de la región nasofrontal en los niños son un reto diagnóstico debido a su rareza, y su potencial comunicación con el sistema nervioso central también aumenta su complicaciones. Dentro de las principales entidades de esta región se encuentran los quistes dermoides, los gliomas nasales y los encefaloceles. Un abordaje diagnóstico y terapéutico inapropiado podría generar desde simples recurrencias hasta fistulas e infecciones en el sistema nervioso central, que podrían contribuir a mayores complicaciones o incluso, poner en riesgo la vida de los pacientes.


Injuries to the naso-frontal region in children are a diagnostic challenge, associated with their rarity, their complexity also implies their potential communication with the central nervous system. Dermoid cysts, nasal gliomas, and encephaloceles are among the main entities in this region. An inappropriate diagnostic and therapeutic approach could generate from simple recurrences (as in our case), to fistulas and infections of the central nervous system that could contribute to greater complications or even put the lives of patients at risk.


Assuntos
Humanos , Masculino , Criança , Neoplasias Nasais/diagnóstico , Cisto Dermoide/diagnóstico , Nariz/anormalidades , Neoplasias Nasais/cirurgia , Cisto Dermoide/cirurgia
12.
Rev. am. med. respir ; 20(3): 273-274, sept. 2020.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1123097

RESUMO

Paciente masculino portador de hipertesión pulmonar severa refractaria a tratamiento médico, sometido a trasplante bipulmonar durante la pandemia por SARS-CoV-2 en la ciudad de Buenos Aires. Para disminuir el riesgo de contagio se realizaron todas las medidas de prevención actualmente recomendadas, con especial énfasis en el uso del equipo de protección personal, contribuyendo de esta forma con el éxito terapéutico alcanzado.


Male patient with severe pulmonary hypertension refractory to medical treatment who underwent a double-lung transplant during the SARS-CoV-2 in the city of Buenos Aires. In order to reduce the risk of contagion all the currently recommended prevention measures were adopted, especially the use of personal protective equipment, thus contributing to the resultant therapeutic success.


Assuntos
Humanos , Transplante de Pulmão , Infecções por Coronavirus , Síndrome Respiratória Aguda Grave , Pandemias , Hipertensão Pulmonar , Pulmão
13.
Acta otorrinolaringol. cir. cuello (En línea) ; 48(2): 173-178, 2020. tab, graf, ilus
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1103906

RESUMO

Actualmente no es sólito tener pacientes con síntomas causados por la implicación de las amígdalas linguales y que pasemos por alto su sospecha. Los signos y síntomas que pueden presentar los pacientes son variados, desde el síndrome de apnea obstructiva del sueño (síntoma más común) y disfagia hasta tos crónica mal abordada y, por lo mismo, tratada inadecuadamente. Presentamos los casos clínicos de dos pacientes con hipertrofia de amígdalas linguales y una revisión narrativa del tema.


Currently, it is not unusual to have patients with symptoms due to the involvement of lingual tonsils and let us go unnoticed their suspicion. The signs and symptoms that patients may present are varied, from giving obstructive sleep apnea syndrome (the most common symptom) dysphagia to poorly treated and poorly treated chronic cough. We present the clinical cases of two patients with hypertrophy of the lingual tonsils and a narrative review of the subject.


Assuntos
Humanos , Síndromes da Apneia do Sono , Diagnóstico , Hipertrofia
14.
Rev. Fac. Med. (Bogotá) ; 67(4): 623-628, Oct.-Dec. 2019. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1091988

RESUMO

Abstract Introduction: Papillary thyroid carcinoma is the most common endocrine neoplasm; therefore, markers with possible prognostic utility have been evaluated. Objective: To analyze the presence of RET/PTC1 rearrangement, lymphocytic thyroiditis and associated clinical features in patients with papillary thyroid cancer treated at the Hospital de San José in Bogotá, Colombia. Materials and methods: Clinical records of patients with complete thyroidectomy and diagnosis of papillary cancer were retrospectively identified. RNA was extracted from tumor tissue, and cDNA was obtained using inverse transcriptase to detect the rearrangement of the RET/PTC1 gene by means of qPCR. Results: 55 patients with papillary thyroid cancer were selected; 93% were females, and the mean age was 45.8 years. The most frequent histological variant was classic (49%). A relationship was found between lymphocytic thyroiditis and the number of positive nodes in segments other than central draining, as well as thyroiditis and antithyroid antibody value. No RET/PTC1 rearrangement expression was found. Conclusions: A relationship between lymphocytic thyroiditis and the number of positive nodes in segments other than central draining was found. Other molecular markers should be searched to differentiate the prognosis of these patients.


Resumen Introducción. El carcinoma papilar de tiroides es la neoplasia endocrina más común, por lo que se han evaluado marcadores con posible utilidad pronóstica. Objetivo. Analizar la presencia del rearreglo del RET/PTC1, tiroiditis linfocítica y características clínicas asociadas en pacientes con cáncer papilar de tiroides en el Hospital de San José de Bogotá D.C., Colombia. Materiales y métodos. Los casos con diagnóstico de cáncer papilar y tiroidectomía completa fueron seleccionados utilizando el registro de historias clínicas; el ARN se extrajo a partir del tejido tumoral y el ADNc se obtuvo utilizando una transcriptasa inversa para luego detectar el rearreglo del gen RET/PTC1 por medio de qPCR. Resultados. Se seleccionaron 55 pacientes con cáncer papilar de tiroides; 93% correspondió a género femenino, la edad promedio fue de 45.8 años y la variante histológica más frecuente fue la clásica (49%). Se evidenció una relación entre tiroiditis linfocítica y la cantidad de ganglios positivos en segmentos distintos al vaciamiento central, así como la tiroiditis y el valor de los anticuerpos antitiroideos. No se identificó la expresión del rearreglo RET/PTC1 en las muestras analizadas. Conclusiones. Se muestra una relación entre tiroiditis linfocítica y la cantidad de ganglios positivos en segmentos distintos al vaciamiento central. Se debe continuar la búsqueda de otros marcadores moleculares que permitan diferenciar el pronóstico en estos pacientes.

15.
Funct Integr Genomics ; 19(1): 171-190, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30244303

RESUMO

Elevated CO2 along with drought is a serious global threat to crop productivity. Therefore, understanding the molecular mechanisms plants use to protect these stresses is the key for plant growth and development. In this study, we mimicked natural stress conditions under a controlled Soil-Plant-Atmosphere-Research (SPAR) system and provided the evidence for how miRNAs regulate target genes under elevated CO2 and drought conditions. Significant physiological and biomass data supported the effective utilization of source-sink (leaf to root) under elevated CO2. Additionally, elevated CO2 partially rescued the effect of drought on total biomass. We identified both known and novel miRNAs differentially expressed during drought, CO2, and combined stress, along with putative targets. A total of 32 conserved miRNAs belonged to 23 miRNA families, and 25 novel miRNAs were identified by deep sequencing. Using the existing sweet potato genome database and stringent analyses, a total of 42 and 22 potential target genes were predicted for the conserved and novel miRNAs, respectively. These target genes are involved in drought response, hormone signaling, photosynthesis, carbon fixation, sucrose and starch metabolism, etc. Gene ontology and KEGG ontology functional enrichment revealed that these miRNAs might target transcription factors (MYB, TCP, NAC), hormone signaling regulators (ARF, AP2/ERF), cold and drought factors (corA), carbon metabolism (ATP synthase, fructose-1,6-bisphosphate), and photosynthesis (photosystem I and II complex units). Our study is the first report identifying targets of miRNAs under elevated CO2 levels and could support the molecular mechanisms under elevated CO2 in sweet potato and other crops in the future.


Assuntos
Dióxido de Carbono/metabolismo , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Ipomoea batatas/genética , MicroRNAs/genética , Folhas de Planta/genética , Raízes de Plantas/genética , Biomassa , Ciclo do Carbono/genética , Secas , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Sequenciamento de Nucleotídeos em Larga Escala , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , MicroRNAs/metabolismo , Anotação de Sequência Molecular , Fotossíntese/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Transdução de Sinais , Estresse Fisiológico/genética
16.
Front Microbiol ; 10: 3055, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32010106

RESUMO

Bacteria have evolved complex sensing and signaling systems to react to their changing environments, most of which are present in all domains of life. Canonical bacterial sensing and signaling modules, such as membrane-bound ligand-binding receptors and kinases, are very well described. However, there are distinct sensing mechanisms in bacteria that are less studied. For instance, the sensing of internal or external cues can also be mediated by changes in protein conformation, which can either be implicated in enzymatic reactions, transport channel formation or other important cellular functions. These activities can then feed into pathways of characterized kinases, which translocate the information to the DNA or other response units. This type of bacterial sensory activity has previously been termed protein activity sensing. In this review, we highlight the recent findings about this non-canonical sensory mechanism, as well as its involvement in metabolic functions and bacterial motility. Additionally, we explore some of the specific proteins and protein-protein interactions that mediate protein activity sensing and their downstream effects. The complex sensory activities covered in this review are important for bacterial navigation and gene regulation in their dynamic environment, be it host-associated, in microbial communities or free-living.

17.
Proc Natl Acad Sci U S A ; 115(52): 13365-13370, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30541885

RESUMO

The chemoreceptor array, a remarkably ordered supramolecular complex, is composed of hexagonally packed trimers of receptor dimers networked by a histidine kinase and one or more coupling proteins. Even though the receptor packing is universal among chemotactic bacteria and archaea, the array architecture has been extensively studied only in selected model organisms. Here, we show that even in the complete absence of the kinase, the cluster II arrays in Vibrio cholerae retain their native spatial localization and the iconic hexagonal packing of the receptors with 12-nm spacing. Our results demonstrate that the chemotaxis array is versatile in composition, a property that allows auxiliary chemotaxis proteins such as ParP and CheV to integrate directly into the assembly. Along with its compositional variability, cluster II arrays exhibit a low degree of structural stability compared with the ultrastable arrays in Escherichia coli We propose that the variability in chemoreceptor arrays is an important mechanism that enables the incorporation of chemotaxis proteins based on their availability.


Assuntos
Células Quimiorreceptoras/metabolismo , Vibrio cholerae/metabolismo , Vibrio cholerae/fisiologia , Archaea/metabolismo , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Quimiotaxia , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Variação Genética/genética , Proteínas de Membrana/metabolismo , Proteínas Quimiotáticas Aceptoras de Metil/metabolismo , Ligação Proteica , Transdução de Sinais
18.
J Bacteriol ; 200(15): e00793-17, 2018 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-29531180

RESUMO

Most motile bacteria are able to bias their movement towards more favorable environments or to escape from obnoxious substances by a process called chemotaxis. Chemotaxis depends on a chemosensory system that is able to sense specific environmental signals and generate a behavioral response. Typically, the signal is transmitted to the bacterial flagellum, ultimately regulating the swimming behavior of individual cells. Chemotaxis is mediated by proteins that assemble into large, highly ordered arrays. It is imperative for successful chemotactic behavior and cellular competitiveness that chemosensory arrays form and localize properly within the cell. Here we review how chemotaxis arrays form and localize in Vibrio cholerae and Vibrio parahaemolyticus We focus on how the ParC/ParP-system mediates cell cycle-dependent polar localization of chemotaxis arrays and thus ensures proper cell pole development and array inheritance upon cell division.

19.
Repert. med. cir ; 27(1): 30-35, 2018. tab.
Artigo em Inglês, Espanhol | LILACS, COLNAL | ID: biblio-911243

RESUMO

Introducción: la prevalencia de la osteoporosis aumenta con la edad, así como la morbimortalidad secundaria a fracturas por fragilidad impactando los costos en salud. Las estrategias creadas han mejorado la detección y manejo de las fracturas. Objetivo: describir las características clínicas de los pacientes con fracturas por fragilidad y su manejo en el Hospital de San José de Bogotá de febrero 2015 a julio 2016, luego de establecer un programa de identificación y prevención de fracturas. Métodos: estudio descriptivo de corte transversal. Se evaluaron las historias clínicas con diagnóstico de osteoporosis severa, analizando las características demográficas, clínicas y tratamiento recibido. Resultados: de 621 pacientes con diagnóstico de osteoporosis y fracturas asociadas, 184 cumplieron los criterios de inclusión. La edad media fue de 71.5 años (DE: 11,6). Las localizaciones más frecuentes fueron radio distal 36%, vertebrales 34%, fémur proximal 18% y otras 11%. El 30% tenían diagnóstico de osteoporosis, de ellos 30% recibieron tratamiento completo antes de la fractura y 57,6% posterior. Conclusión: las fracturas por fragilidad son frecuentes en osteoporosis, aunque hay subdiagnóstico y subtratamiento. La prevención de la segunda fractura se refleja en el aumento del número de pacientes que recibieron tratamiento adecuado, demostrando la necesidad de crear programas de educación.


Introduction: the prevalence of osteoporosis increases with aging, as well as, morbidity and mortality secondary to fragility fractures, impacting costs of healthcare. New strategies have enhanced fragility fractures detection and management. Objective: to describe the clinical features of patients with fragility fractures and their management at Hospital de San José, Bogotá, from February 2015 to July 2016, after establishing a fracture identification and prevention program. Methods: a cross sectional descriptive study. Clinical records of patients diagnosed with severe osteoporosis were reviewed. Demographic and clinical characteristics and treatment outcomes were analyzed. Results: out of 621 patients with osteoporosis-related fractures, 184 met the inclusion criteria. Mean age was 71.5 years (SD: 11.6). Fractures affected the distal radius in 36%, vertebrae in 34%, proximal femur in 18% and other sites in 11%. Osteoporosis was diagnosed in 30% of patients of which 30% received complete treatment for osteoporosis prior to fracture and 57.6% after fracture. Conclusions: fragility fractures are usually associated with osteoporosis, although there is underdiagnosis and under-treatment. Prevention of a future fracture is reflected in the increasing number of patients who received appropriate treatment, demonstrating the need to create education programs.


Assuntos
Humanos , Masculino , Feminino , Idoso , Fraturas Ósseas , Fraturas por Osteoporose , Osteoporose , Deficiência de Vitamina D , Osso e Ossos
20.
Elife ; 62017 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-29058677

RESUMO

Chemotaxis proteins organize into large, highly ordered, chemotactic signaling arrays, which in Vibrio species are found at the cell pole. Proper localization of signaling arrays is mediated by ParP, which tethers arrays to a cell pole anchor, ParC. Here we show that ParP's C-terminus integrates into the core-unit of signaling arrays through interactions with MCP-proteins and CheA. Its intercalation within core-units stimulates array formation, whereas its N-terminal interaction domain enables polar recruitment of arrays and facilitates its own polar localization. Linkage of these domains within ParP couples array formation and localization and results in controlled array positioning at the cell pole. Notably, ParP's integration into arrays modifies its own and ParC's subcellular localization dynamics, promoting their polar retention. ParP serves as a critical nexus that regulates the localization dynamics of its network constituents and drives the localized assembly and stability of the chemotactic machinery, resulting in proper cell pole development.


Assuntos
Proteínas de Bactérias/metabolismo , Quimiotaxia , Proteínas de Membrana/metabolismo , Multimerização Proteica , Vibrio cholerae/fisiologia , Ligação Proteica , Transporte Proteico
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