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1.
Anal Chem ; 96(21): 8721-8729, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38683735

RESUMO

Tyrosine phosphorylation is one of the most important posttranslational modifications in bacteria, linked to regulating growth, migration, virulence, secondary metabolites, biofilm formation, and capsule production. Only two tyrosine kinases (yccC (etk) and wzc) have been identified in Escherichia coli. The investigation by similarity has not revealed any novel BY-kinases in silico so far, most probably due to their sequence and structural variability. Here we developed a reverse-phase protein array from 4126 overexpressed E. coli clones, lysed, and printed on coated glass slides. These high-density E. coli lysate arrays (ECLAs) were quality controlled by the reproducibility and immobilization of total lysate proteins and specific overexpressed proteins. ECLAs were used to interrogate the relationship between protein overexpression and tyrosine phosphorylation in the total lysate. We identified 6 protein candidates, including etk and wzc, with elevated phosphotyrosine signals in the total lysates. Among them, we identified a novel kinase nrdD with autophosphorylation and transphosphorylation activities in the lysates. Moreover, the overexpression of nrdD induced biofilm formation. Since nrdD is a novel kinase, we used E. coli proteome microarrays (purified 4,126 E. coli proteins) to perform an in vitro kinase assay and identified 33 potential substrates. Together, this study established a new ECLA platform for interrogating posttranslational modifications and identified a novel kinase that is important in biofilm formation, which will shed some light on bacteria biochemistry and new ways to impede drug resistance.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Análise Serial de Proteínas , Proteínas Tirosina Quinases , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas de Escherichia coli/metabolismo , Fosforilação , Biofilmes
2.
Parasit Vectors ; 16(1): 274, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563668

RESUMO

Bovine babesiosis, caused by different Babesia spp. such as B. bovis, B. bigemina, B. divergens, and B. major, is a global disease that poses a serious threat to livestock production. Babesia bovis infections are associated with severe disease and increased mortality in adult cattle, making it the most virulent agent of bovine babesiosis. Babesia bovis parasites undergo asexual reproduction within bovine red blood cells, followed by sexual reproduction within their tick vectors, which transmit the parasite transovarially. Current control methods, including therapeutic drugs (i.e., imidocarb) have been found to lead to drug resistance. Moreover, changing environmental factors add complexity to efficient parasite control. Understanding the fundamental biology, host immune responses, and host-parasite interactions of Babesia parasites is critical for developing next-generation vaccines to control acute disease and parasite transmission. This systematic review analyzed available research papers on vaccine development and the associated immune responses to B. bovis. We compiled and consolidated the reported vaccine strategies, considering the study design and rationale of each study, to provide a systematic review of knowledge and insights for further research. Thirteen studies published since 2014 (inclusive) represented various vaccine strategies developed against B. bovis such as subunit, live attenuated, and viral vector vaccines. Such strategies incorporated B. bovis proteins or whole live parasites with the latter providing the most effective prophylaxis against bovine babesiosis. Incorporating novel research approaches, such as "omics" will enhance our understanding of parasite vulnerabilities.


Assuntos
Babesia bovis , Babesia , Babesiose , Doenças dos Bovinos , Vacinas , Animais , Bovinos , Babesiose/parasitologia , Doenças dos Bovinos/parasitologia
3.
Cancer ; 128(11): 2182-2192, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363879

RESUMO

BACKGROUND: Peptide receptor radionuclide therapy (PRRT) has shown favorable results in neuroendocrine tumors (NETs). Long-term safety and efficacy data for 177 Lu-octreotate PRRT, particularly in combination with chemotherapy, is lacking. METHODS: The authors conducted a retrospective review of the long-term toxicity and survival outcomes of 104 patients with advanced NETs treated on 4 phase 2 clinical trials with Lutetium-177-octreotate (177 Lu-octreotate) PRRT, mostly in combination with chemotherapy. Median follow-up was 68 months, which represents the longest follow-up study of 177 Lu-octreotate PRRT for NETs to date. RESULTS: Median progression-free survival (PFS) was 37 months, and median overall survival (OS) was 71 months. Five- and 10-year OS were 62% and 29%, and 5- and 10-year PFS were 36% and 21%, respectively, demonstrating 177 Lu-octreotate can provide durable responses. PRRT was well tolerated with 1.9% of patients developing chronic renal impairment and 1% of patients developing long-term thrombocytopenia. Interestingly, there was a relatively high rate of myelodysplasia (MDS)/leukemia (6.7%), possibly attributable to the longer follow-up (with all except 1 case occurring more than 4 years after PRRT treatment) or to the addition of concurrent chemotherapy. CONCLUSIONS: Lutetium-177-Octreotate PRRT remains an efficacious and well tolerated treatment in long-term follow-up. For clinicians deciding on the timing of PRRT for individual patients, the 6.7% long-term risk of MDS/leukemia needs to be balanced against the 21% PFS at 10 years.


Assuntos
Leucemia , Tumores Neuroendócrinos , Compostos Organometálicos , Seguimentos , Humanos , Leucemia/tratamento farmacológico , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/radioterapia , Octreotida/efeitos adversos , Compostos Organometálicos/efeitos adversos , Radioisótopos/efeitos adversos
4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21268513

RESUMO

IntroductionA discussion of waves of the COVID-19 epidemic in different countries is a part of the national conversation for many, but there is no hard and fast means of delineating these waves in the available data and their connection to waves in the sense of mathematical epidemiology is only tenuous. MethodsWe present an algorithm which processes a general time series to identify substantial, significant and sustained periods of increase in the value of the time series, which could reasonably be described as observed waves. This provides an objective means of describing observed waves in time series. ResultsThe output of the algorithm as applied to epidemiological time series related to COVID-19 corresponds to visual intuition and expert opinion. Inspecting the results of individual countries shows how consecutive observed waves can differ greatly with respect to the case fatality ratio. Furthermore, in large countries, a more detailed analysis shows that consecutive observed waves have different geographical ranges. We also show how waves can be modulated by government interventions and find that early implementation of non-pharmaceutical interventions correlates with a reduced number of observed waves and reduced mortality burden in those waves. ConclusionIt is possible to identify observed waves of disease by algorithmic methods and the results can be fruitfully used to analyse the progression of the epidemic.

5.
J Vis Exp ; (173)2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34369926

RESUMO

Transcranial magnetic stimulation (TMS) is a common tool used to measure the behavior of motor circuits in healthy and neurologically impaired populations. TMS is used extensively to study motor control and the response to neurorehabilitation of the upper extremities. However, TMS has been less utilized in the study of lower extremity postural and walking-specific motor control. The limited use and the additional methodological challenges of lower extremity TMS assessments have contributed to the lack of consistency in lower extremity TMS procedures within the literature. Inspired by the decreased ability to record lower extremity TMS motor evoked potentials (MEP), this methodological report details steps to enable post-stroke TMS assessments in a standing posture. The standing posture allows for the activation of the neuromuscular system, reflecting a state more akin to the system's state during postural and walking tasks. Using dual-top force plates, we instructed participants to equally distribute their weight between their paretic and non-paretic legs. Visual feedback of the participants' weight distribution was provided. Using image guidance software, we delivered single TMS pulses via a double-cone coil to the participants' lesioned and non-lesioned hemispheres and measured the corticomotor response of the paretic and non-paretic tibialis anterior and soleus muscles. Performing assessments in the standing position increased the TMS response rate and allowed for the use of the lower stimulation intensities compared to the standard sitting/resting position. Utilization of this TMS protocol can provide a common approach to assess the lower extremity corticomotor response post-stroke when the neurorehabilitation of postural and gait impairments are of interest.


Assuntos
Córtex Motor , Acidente Vascular Cerebral , Potencial Evocado Motor , Humanos , Extremidade Inferior , Músculo Esquelético , Posição Ortostática , Estimulação Magnética Transcraniana
6.
Front Hum Neurosci ; 14: 578127, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33328932

RESUMO

Background: In this pilot study, we examined the effects of ipsilesional high-frequency rTMS (iHF-rTMS) and contralesional low-frequency rTMS (cLF-rTMS) applied via a double-cone coil on neurophysiological and gait variables in patients with chronic stroke. Objective/Hypothesis: To determine the group and individual level effects of two types of stimulation to better individualize neuromodulation for rehabilitation. Methods: Using a randomized, within-subject, double-blind, sham-controlled trial with 14 chronic stroke participants iHF-rTMS and cLF-rTMS were applied via a double-cone coil to the tibialis anterior cortical representation. Neurophysiological and gait variables were compared pre-post rTMS. Results: A small effect of cLF-rTMS indicated increased MEP amplitudes (Cohen's D; cLF-rTMS, d = -0.30). Group-level analysis via RMANOVA showed no significant group effects of stimulation (P > 0.099). However, secondary analyses of individual data showed a high degree of response variability to rTMS. Individual percent changes in resting motor threshold and normalized MEP latency correlated with changes in gait propulsive forces and walking speed (iHF-rTMS, nLAT:Pp, R = 0.632 P = 0.015; cLF-rTMS, rMT:SSWS, R = -0.557, P = 0.039; rMT:Pp, R = 0.718, P = 0.004). Conclusions: Changes in propulsive forces and walking speed were seen in some individuals that showed neurophysiological changes in response to rTMS. The neurological consequences of stroke are heterogeneous making a "one type fits all" approach to neuromodulation for rehabilitation unlikely. This pilot study suggests that an individual's unique response to rTMS should be considered before the application/selection of neuromodulatory therapies. Before neuromodulatory therapies can be incorporated into standard clinical practice, additional work is needed to identify biomarkers of response and how best to prescribe neuromodulation for rehabilitation for post-stroke gait.

7.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20177147

RESUMO

Oxford COVID-19 Database (OxCOVID19 Database) is a comprehensive source of information related to the COVID-19 pandemic. This relational database contains time-series data on epidemiology, government responses, mobility, weather and more across time and space for all countries at the national level, and for more than 50 countries at the regional level. It is curated from a variety of (wherever available) official sources. Its purpose is to facilitate the analysis of the spread of SARS-CoV-2 virus and to assess the effects of non-pharmaceutical interventions to reduce the impact of the pandemic. Our database is a freely available, daily updated tool that provides unified and granular information across geographical regions.

8.
Front Neurosci ; 13: 286, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31031579

RESUMO

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique used to modulate cortical activity. However, measured effects on clinically relevant assessments have been inconsistent, possibly due to the non-focal dispersion of current from traditional two electrode configurations. High-definition (HD)-tDCS uses a small array of electrodes (N = 5) to improve targeted current delivery. The purpose of this study was to determine the effects of a single session of anodal and cathodal HD-tDCS on gait kinematics and kinetics and the corticomotor response to transcranial magnetic stimulation (TMS) in individuals post-stroke. We hypothesized that ipsilesional anodal stimulation would increase the corticomotor response to TMS leading to beneficial changes in gait. Eighteen participants post-stroke (average age: 64.8 years, SD: 12.5; average months post-stroke: 54, SD: 42; average lower extremity Fugl-Meyer score: 26, SD: 6) underwent biomechanical and corticomotor response testing on three separate occasions prior to and after HD-tDCS stimulation. In a randomized order, anodal, cathodal, and sham HD-tDCS were applied to the ipsilesional motor cortex for 20 min while participants pedaled on a recumbent cycle ergometer. Gait kinetic and kinematic data were collected while walking on an instrumented split-belt treadmill with motion capture. The corticomotor response of the paretic and non-paretic tibialis anterior (TA) muscles were measured using neuronavigated TMS. Repeated measures ANOVAs using within-subject factors of time point (pre, post) and stimulation type (sham, anodal, cathodal) were used to compare effects of HD-tDCS stimulation on measured variables. HD-tDCS had no effect on over ground walking speed (P > 0.41), or kinematic variables (P > 0.54). The corticomotor responses of the TA muscles were also unaffected by HD-tDCS (resting motor threshold, P = 0.15; motor evoked potential (MEP) amplitude, P = 0.25; MEP normalized latency, P = 0.66). A single session of anodal or cathodal HD-tDCS delivered to a standardized ipsilesional area of the motor cortex does not appear to alter gait kinematics or corticomotor response post-stroke. Repeated sessions and individualized delivery of HD-tDCS may be required to induce beneficial plastic effects. Contralesional stimulation should also be investigated due to the altered interactions between the cerebral hemispheres post-stroke.

9.
Acta Medica Philippina ; : 31-35, 2019.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-979666

RESUMO

Objective@#The study aimed to determine if Blumea balsamifera inhibits calcium oxalate stone formation in the kidneys through determination of the number of calcium oxalate stones in the renal cortex and the percent mass of calcium oxalate.@*Methods@#Post-test only control group design was used using five treatment groups with placebo as the negative control, potassium citrate as the positive control, and 50%, 100%, and 200% sambong treatment. Urolithiasis was induced through ethylene glycol and ammonium chloride. Each treatment group was administered its corresponding treatment solution once daily for twenty-one days. Histopathologic examination and kidney homogenate analysis were done to determine the degree of deposition of calcium oxalate stones in renal tissues and the oxalate content, respectively. Statistical analyses were performed using one-way ANOVA and post hoc Gabriel's Pairwise Comparisons Test.@*Results@#The 100% sambong treatment group showed the least mean number of stones while the positive control and 50% sambong treatment group exhibited the highest anti-urolithiatic activity in terms of oxalate content of the kidney homogenate.@*Conclusion@#It can be concluded from the study that Blumea balsamifera inhibits calcium oxalate stone formation in the kidneys with the 100% and 50% sambong treatment most effective in decreasing number of stones and oxalate content of the kidney homogenate, respectively.


Assuntos
Urolitíase , Rim
10.
Cultur Divers Ethnic Minor Psychol ; 20(4): 483-90, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25111540

RESUMO

Research shows groups who experience minority status encounter tokenization. Most studies applying token theory to minority groups at work focus on either gendered or racialized processes of tokenization. We offer a different approach by using an intersectional lens to examine how both race and gender work together to shape ways Black professional men experience tokenization when employed in predominantly White male-dominated workplaces. Based on interviews with 42 Black men employed as doctors, lawyers, bankers, or engineers, we conclude that although Black professional men encounter some of the typical negative aspects of tokenization, intersections of race and gender create other important facets that render their token experience somewhat unique and different from their White male, White female, and Black female counterparts.


Assuntos
População Negra , Negro ou Afro-Americano , Identidade de Gênero , População Branca , Adulto , Feminino , Humanos , Entrevistas como Assunto , Masculino , Fatores Sexuais , Estados Unidos
11.
Clin Nucl Med ; 37(8): 732-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22785498

RESUMO

PURPOSE: This study aimed to establish the safety of outpatient 131I-rituximab radioimmunotherapy by measuring the radiation exposure of hospital staff, carers, and members of the public and by estimating the environmental impact of radioactive urinary excretion. METHODS: Two hundred consecutive outpatients treated with 131I-rituximab radioimmunotherapy of non-Hodgkin lymphoma (NHL) with therapeutic activities between 1 and 4.5 GBq (mean, 2.3 GBq; or between 27 and 121 mCi; mean, 62 mCi) predicated on a prescribed whole-body radiation-absorbed dose of 0.75 Gy were studied. Their 279 family members/carers and 432 visitors wore thermoluminescent dosimeter badges for the week during which the patients were confined to their home after treatment. RESULTS: All 200 patients received 131I-rituximab activities according to the prescribed dose of 0.75 Gy to the whole body. From 200 consecutive patients, over the 7 days after therapy, mean radiation exposure of adult carers was 0.49 mSv (range, <0.01 to 3.67 mSv). To other coresiding family members, mean exposure was 0.23 mSv (range, <0.01 to 1.20 mSv), and for visitors sharing badges, the mean exposure was 0.17 mSv (range, <0.01 to 0.73 mSv). Urinary activity excreted over the week after 131I-rituximab therapy was typically less than 25% of the administered activity. CONCLUSIONS: 131I-rituximab radioimmunotherapy for non-Hodgkin lymphoma may be safely administered on an outpatient basis. The median radiation exposure of carers, cohabitants of the patient, and visitors is well within the limits recommended by international guidelines. Local regulatory agency-designated patient release rate limit of less than 25 µSv/h at 1 m was attained within 1 week of therapeutic 131I-rituximab administration.


Assuntos
Anticorpos Monoclonais Murinos/efeitos adversos , Anticorpos Monoclonais Murinos/uso terapêutico , Linfoma não Hodgkin/radioterapia , Pacientes Ambulatoriais , Radioimunoterapia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/urina , Cuidadores , Relação Dose-Resposta à Radiação , Família , Meia-Vida , Humanos , Pessoa de Meia-Idade , Rituximab , Fatores de Tempo , Irradiação Corporal Total
13.
Dalton Trans ; (45): 10106-13, 2009 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-19904438

RESUMO

Photosystem I/dithiol molecular wire/nanoparticle bioconjugates have been shown to photocatalytically generate dihydrogen at linear rates when continuously illuminated. In an effort to maximize H2 production, the pH and ionic concentration of the solution, the mobility of the electron donor, the length and degree of saturation of the molecular wire, and the intensity of the light were systematically investigated. Optimal conditions included a solution buffered at pH 6.0, cross-linked plastocyanin, rebuilt spinach PS I, and the use of 1,4-benzenedithiol to connect PS I to the Pt nanoparticle. Illumination of this optimized Photosystem I/dithiol molecular wire/nanoparticle bioconjugate at a light intensity of 70 microE m(-2) s(-1) generated a measured one time H2 production rate of 312 micromol H2 mg Chl(-1) h(-1).


Assuntos
Hidrogênio/química , Nanopartículas Metálicas/química , Complexo de Proteína do Fotossistema I , Plastocianina/química , Platina/química , Spinacia oleracea/química , Tolueno/análogos & derivados , Concentração de Íons de Hidrogênio , Modelos Biológicos , Modelos Moleculares , Folhas de Planta/química
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