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1.
BMC Med Inform Decis Mak ; 23(1): 201, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794423

RESUMO

BACKGROUND: Obesity is a multifaceted condition that impacts individuals across various age, racial, and socioeconomic demographics, hence rendering them susceptible to a range of health complications and an increased risk of premature mortality. The frequency of obesity among adolescent females in Iran has exhibited an increase from 6 to 9%, while among boys, it has risen from 2 to 7%. Due to the increasing prevalence and advancements in technology, the primary objective of this study was to develop and evaluate a smartphone-based app that would serve as an educational tool for parents about the matter of childhood overweight and obesity. Additionally, the app aimed to enhance parents' capacity to effectively address and manage their children's weight-related concerns. METHODS: The design of the present study is of an applied-developmental type. In the first phase, the content of related smartphone-based app was determined based on the needs identified in similar studies and the findings of a researcher-made questionnaire. The versions of the app were designed in the android studio 3 programming environment, using the Java 8 programming language and SQLite database. Then, in order to evaluate the app's usability, ease of access, and different features, the standard usability evaluation questionnaire and the user satisfaction questionnaire (QUIS) were completed by the users. RESULTS: The developed app has five main sections: the main page, recommendation section (with eight parts), charts over the time, child psychology, and reminders for each user. The designed app was given to 20 people including nutritionists and parents with children under 18 years of age for conducting usability evaluation. According to the scores of participants about the usability evaluation of the app, it can be concluded that groups participating in the study could use the program, and they rated the app at a "good" level. Overall performance of the app, screen capabilities, terms and information of the program, learnability, and general features are scored higher than 7.5 out of 9. CONCLUSION: By using this app, people can become familiar with the causes and symptoms of weight imbalance and manage their weight as best as possible. This app can be considered as a model for designing and creating similar broader systems and programs for the prevention, management, treatment and care of diseases, which aim to help control diseases as much as possible and increase the quality of life and reduce complications for be patients.


Assuntos
Aplicativos Móveis , Obesidade Infantil , Masculino , Criança , Feminino , Adolescente , Humanos , Smartphone , Obesidade Infantil/prevenção & controle , Sobrepeso/prevenção & controle , Qualidade de Vida
2.
J Neurochem ; 158(4): 960-979, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33991113

RESUMO

In Parkinson's disease, dopamine-containing nigrostriatal neurons undergo profound degeneration. Tyrosine hydroxylase (TH) is the rate-limiting enzyme in dopamine biosynthesis. TH increases in vitro formation of reactive oxygen species, and previous animal studies have reported links between cytosolic dopamine build-up and oxidative stress. To examine effects of increased TH activity in catecholaminergic neurons in vivo, we generated TH-over-expressing mice (TH-HI) using a BAC-transgenic approach that results in over-expression of TH with endogenous patterns of expression. The transgenic mice were characterized by western blot, qPCR, and immunohistochemistry. Tissue contents of dopamine, its metabolites, and markers of oxidative stress were evaluated. TH-HI mice had a 3-fold increase in total and phosphorylated TH levels and an increased rate of dopamine synthesis. Coincident with elevated dopamine turnover, TH-HI mice showed increased striatal production of H2 O2 and reduced glutathione levels. In addition, TH-HI mice had elevated striatal levels of the neurotoxic dopamine metabolites 3,4-dihydroxyphenylacetaldehyde and 5-S-cysteinyl-dopamine and were more susceptible than wild-type mice to the effects of amphetamine and methamphetamine. These results demonstrate that increased TH alone is sufficient to produce oxidative stress in vivo, build up autotoxic dopamine metabolites, and augment toxicity.


Assuntos
Anfetamina/farmacologia , Catecolaminas/metabolismo , Estimulantes do Sistema Nervoso Central/farmacologia , Estresse Oxidativo , Tirosina 3-Mono-Oxigenase/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/análogos & derivados , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Dopamina/análogos & derivados , Dopamina/metabolismo , Feminino , Dosagem de Genes , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/genética
3.
Opt Express ; 28(15): 21749-21765, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32752448

RESUMO

Gas dynamic virtual nozzles (GDVNs) produce microscopic flow-focused liquid jets and droplets and play an important role at X-ray free-electron laser (XFEL) facilities where they are used to steer a stream of hydrated biomolecules into an X-ray focus during diffraction measurements. Highly stable and reproducible microjet and microdroplets are desired, as are flexible fabrication methods that enable integrated mixing microfluidics, droplet triggering mechanisms, laser illumination, and other customized features. In this study, we develop the use of high-resolution 3D nano-printing for the production of monolithic, asymmetric GDVN designs that are difficult to fabricate by other means. We also develop a dual-pulsed nanosecond image acquisition and analysis platform for the characterization of GDVN performance, including jet speed, length, diameter, and directionality, among others. We show that printed GDVNs can form microjets with very high degree of reproducibility, down to sub-micron diameters, and with water jet speeds beyond 170 m/s.

4.
Pharmacol Res ; 117: 242-251, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28027910

RESUMO

A substantial number of G-protein coupled receptors (GPCRs) genetic disorders are due to mutations that cause misfolding or dysfunction of the receptor product. Pharmacological chaperoning approaches can rescue such mutant receptors by stabilizing protein conformations that behave similar to the wild type protein. For example, this can be achieved by improving folding efficiency and/or interaction with chaperone proteins. Although efficacy of pharmacological chaperones has been demonstrated in vitro for a variety of GPCRs, translation to clinical use has been limited. In this paper we discuss the history of pharmacological chaperones of GPCR's and other membrane proteins, the challenges in translation to the clinic, and the use of different assays for pharmacological chaperone discovery.


Assuntos
Proteínas de Membrana/metabolismo , Chaperonas Moleculares/metabolismo , Mutação/genética , Receptores Acoplados a Proteínas G/genética , Animais , Humanos , Proteínas de Membrana/genética , Dobramento de Proteína , Receptores Acoplados a Proteínas G/metabolismo
5.
Clin Med Insights Oncol ; 18: 11795549241236409, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510317

RESUMO

The treatment of locally advanced rectal cancer (LARC) is a challenging situation for radiation oncologists and colorectal surgeons. Most current approaches recommend neoadjuvant fluorouracil or capecitabine-based chemoradiotherapy followed by surgery as a standard of care. Intensification of concurrent chemotherapy by adding oxaliplatin to fluorouracil or capecitabine backbone to get better outcomes is the matter that has remained unresolved. In this review, we searched Medline and Google Scholar databases and selected 28 prospective phase II and III clinical trials that addressed this question. We discussed the potential advantages and drawbacks of incorporating oxaliplatin into concurrent chemoradiation therapy. We tried to define whether adding oxaliplatin to concurrent chemoradiation with excellent performance and high-risk features benefits some subpopulations. The available literature suggests that by adding oxaliplatin there are some benefits in enhancing response to neoadjuvant chemoradiotherapy, however, without any translated improvements in long-term outcomes including overall and disease-free survival.

6.
Brain Struct Funct ; 228(7): 1725-1739, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37493690

RESUMO

During the prenatal period and the first postnatal years, the human brain undergoes rapid growth, which establishes a preliminary infrastructure for the subsequent development of cognition and behavior. To understand the underlying processes of brain functioning and identify potential sources of developmental disorders, it is essential to uncover the developmental rules that govern this critical period. In this study, graph theory modeling and network science analysis were employed to investigate the impact of age, gender, weight, and typical and atypical development on brain development. Local and global topologies of functional connectomes obtained from rs-fMRI data were collected from 421 neonates aged between 31 and 45 postmenstrual weeks who were in natural sleep without any sedation. The results showed that global efficiency, local efficiency, clustering coefficient, and small-worldness increased with age, while modularity and characteristic path length decreased with age. The normalized rich-club coefficient displayed a U-shaped pattern during development. The study also examined the global and local impacts of gender, weight, and group differences between typical and atypical cases. The findings presented some new insights into the maturation of functional brain networks and their relationship with cognitive development and neurodevelopmental disorders.


Assuntos
Conectoma , Imageamento por Ressonância Magnética , Feminino , Gravidez , Humanos , Recém-Nascido , Lactente , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Cognição , Conectoma/métodos
7.
Adv Biomed Res ; 12: 65, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37200765

RESUMO

Background: Self-care applications are effective in the control and treatment of disease symptoms. Today, the mobile phone is used as one of the tools that can help us in this regard. The present study attempts to develop and evaluate a functional self-care mobile-phone application for patients with skin and hair problems using treatment protocols of herbal medicine. Materials and Methods: This study is a descriptive-applied type. At first, a questionnaire was prepared for data need assessment and also to determine the data items and required capabilities of the application. Based on the results, an application was designed using the Java programing language in the Android software environment. In the next step, the application was installed on the mobile phones of several specialists and patients, and the necessary corrections were made. Then, the final version of the application was evaluated. Results: The most critical data elements of the mobile application for skin and hair patients included the application's functionality, temperament survey, and clinical information. After considering users' feedback, the screen functionality, the application's information and idiom, and overall functionality of the application were evaluated and approved by the users. Conclusion: By and large, the developed application could help the patients to receive the best and high-priority treatment protocols based on their own temperament.

8.
eNeuro ; 10(5)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37142435

RESUMO

With a wide variety of dopamine transporter (DAT) antibodies available commercially, it is important to validate which antibodies provide sufficient immunodetection for reproducibility purpose and for accurate analysis of DAT levels and/or location. Commercially available DAT antibodies that are commonly used were tested in western blotting (WB) on wild-type (WT) and DAT-knock-out (DAT-KO) brain tissue and with immunohistology (IH) techniques against coronal slices of unilaterally lesioned 6-OHDA rats, in addition to wild-type and DAT-knock-out mice. DAT-KO mice and unilateral 6-OHDA lesions in rats were used as a negative control for DAT antibody specificity. Antibodies were tested at various concentrations and rated based on signal detection varying from no signal to optimal signal detection. Commonly used antibodies, including AB2231 and PT-22 524-1-AP, did not provide specific DAT signals in WB and IH. Although certain antibodies provided a good DAT signal, such as SC-32258, D6944, and MA5-24796, they also presented nonspecific bands in WB. Many DAT antibodies did not detect the DAT as advertised, and this characterization of DAT antibodies may provide a guide for immunodetection of DAT for molecular studies.


Assuntos
Encéfalo , Proteínas da Membrana Plasmática de Transporte de Dopamina , Ratos , Camundongos , Animais , Oxidopamina/toxicidade , Reprodutibilidade dos Testes , Camundongos Knockout
9.
Structure ; 31(2): 138-151.e5, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36630960

RESUMO

NendoU from SARS-CoV-2 is responsible for the virus's ability to evade the innate immune system by cleaving the polyuridine leader sequence of antisense viral RNA. Here we report the room-temperature structure of NendoU, solved by serial femtosecond crystallography at an X-ray free-electron laser to 2.6 Å resolution. The room-temperature structure provides insight into the flexibility, dynamics, and other intrinsic properties of NendoU, with indications that the enzyme functions as an allosteric switch. Functional studies examining cleavage specificity in solution and in crystals support the uridine-purine cleavage preference, and we demonstrate that enzyme activity is fully maintained in crystal form. Optimizing the purification of NendoU and identifying suitable crystallization conditions set the benchmark for future time-resolved serial femtosecond crystallography studies. This could advance the design of antivirals with higher efficacy in treating coronaviral infections, since drugs that block allosteric conformational changes are less prone to drug resistance.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Cristalografia por Raios X , Temperatura , Elétrons , Lasers
10.
Lab Chip ; 23(13): 3016-3033, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37294576

RESUMO

Droplet injection strategies are a promising tool to reduce the large amount of sample consumed in serial femtosecond crystallography (SFX) measurements at X-ray free electron lasers (XFELs) with continuous injection approaches. Here, we demonstrate a new modular microfluidic droplet injector (MDI) design that was successfully applied to deliver microcrystals of the human NAD(P)H:quinone oxidoreductase 1 (NQO1) and phycocyanin. We investigated droplet generation conditions through electrical stimulation for both protein samples and implemented hardware and software components for optimized crystal injection at the Macromolecular Femtosecond Crystallography (MFX) instrument at the Stanford Linac Coherent Light Source (LCLS). Under optimized droplet injection conditions, we demonstrate that up to 4-fold sample consumption savings can be achieved with the droplet injector. In addition, we collected a full data set with droplet injection for NQO1 protein crystals with a resolution up to 2.7 Å, leading to the first room-temperature structure of NQO1 at an XFEL. NQO1 is a flavoenzyme associated with cancer, Alzheimer's and Parkinson's disease, making it an attractive target for drug discovery. Our results reveal for the first time that residues Tyr128 and Phe232, which play key roles in the function of the protein, show an unexpected conformational heterogeneity at room temperature within the crystals. These results suggest that different substates exist in the conformational ensemble of NQO1 with functional and mechanistic implications for the enzyme's negative cooperativity through a conformational selection mechanism. Our study thus demonstrates that microfluidic droplet injection constitutes a robust sample-conserving injection method for SFX studies on protein crystals that are difficult to obtain in amounts necessary for continuous injection, including the large sample quantities required for time-resolved mix-and-inject studies.


Assuntos
Lasers , Proteínas , Humanos , Cristalografia por Raios X , Proteínas/química , Injeções , NAD(P)H Desidrogenase (Quinona)
11.
Front Cell Neurosci ; 16: 832536, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35614973

RESUMO

Mutations in the dopamine transporter gene (SLC6A3) have been implicated in many human diseases. Among these is the infantile parkinsonism-dystonia known as Dopamine Transporter Deficiency Syndrome (DTDS). Afflicted individuals have minimal to no functional dopamine transporter protein. This is primarily due to retention of misfolded disease-causing dopamine transporter variants. This results in a variety of severe motor symptoms in patients and the disease ultimately leads to death in adolescence or young adulthood. Though no treatment is currently available, pharmacological chaperones targeting the dopamine transporter have been shown to rescue select DTDS disease-causing variants. Previous work has identified two DAT pharmacological chaperones with moderate potency and efficacy: bupropion and ibogaine. In this study, we carried out structure-activity relationships (SARs) for bupropion and ibogaine with the goal of identifying the chemical features required for pharmacological chaperone activity. Our results show that the isoquinuclidine substituent of ibogaine and its analogs is an important feature for pharmacological chaperone efficacy. For bupropion, the secondary amine group is essential for pharmacological chaperone activity. Lastly, we describe additional ibogaine and bupropion analogs with varying chemical modifications and variable pharmacological chaperone efficacies at the dopamine transporter. Our results contribute to the design and refinement of future dopamine transporter pharmacological chaperones with improved efficacies and potencies.

13.
Biophys Rep (N Y) ; 2(4): 100081, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36425668

RESUMO

With advances in X-ray free-electron lasers (XFELs), serial femtosecond crystallography (SFX) has enabled the static and dynamic structure determination for challenging proteins such as membrane protein complexes. In SFX with XFELs, the crystals are typically destroyed after interacting with a single XFEL pulse. Therefore, thousands of new crystals must be sequentially introduced into the X-ray beam to collect full data sets. Because of the serial nature of any SFX experiment, up to 99% of the sample delivered to the X-ray beam during its "off-time" between X-ray pulses is wasted due to the intrinsic pulsed nature of all current XFELs. To solve this major problem of large and often limiting sample consumption, we report on improvements of a revolutionary sample-saving method that is compatible with all current XFELs. We previously reported 3D-printed injection devices coupled with gas dynamic virtual nozzles (GDVNs) capable of generating samples containing droplets segmented by an immiscible oil phase for jetting crystal-laden droplets into the path of an XFEL. Here, we have further improved the device design by including metal electrodes inducing electrowetting effects for improved control over droplet generation frequency to stimulate the droplet release to matching the XFEL repetition rate by employing an electrical feedback mechanism. We report the improvements in this electrically triggered segmented flow approach for sample conservation in comparison with a continuous GDVN injection using the microcrystals of lysozyme and 3-deoxy-D-manno-octulosonate 8-phosphate synthase and report the segmented flow approach for sample injection applied at the Macromolecular Femtosecond Crystallography instrument at the Linear Coherent Light Source for the first time.

14.
J Appl Crystallogr ; 55(Pt 1): 1-13, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35153640

RESUMO

Serial femtosecond crystallography (SFX) is a powerful technique that exploits X-ray free-electron lasers to determine the structure of macro-molecules at room temperature. Despite the impressive exposition of structural details with this novel crystallographic approach, the methods currently available to introduce crystals into the path of the X-ray beam sometimes exhibit serious drawbacks. Samples requiring liquid injection of crystal slurries consume large quantities of crystals (at times up to a gram of protein per data set), may not be compatible with vacuum configurations on beamlines or provide a high background due to additional sheathing liquids present during the injection. Proposed and characterized here is the use of an immiscible inert oil phase to supplement the flow of sample in a hybrid microfluidic 3D-printed co-flow device. Co-flow generation is reported with sample and oil phases flowing in parallel, resulting in stable injection conditions for two different resin materials experimentally. A numerical model is presented that adequately predicts these flow-rate conditions. The co-flow generating devices reduce crystal clogging effects, have the potential to conserve protein crystal samples up to 95% and will allow degradation-free light-induced time-resolved SFX.

15.
Med Sci Monit ; 17(10): CR537-41, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21959605

RESUMO

BACKGROUND: Some patients with right heart failure develop cardiac hepatopathy (CH). The pathophysiology of CH is thought to be secondary to hepatic venous congestion and arterial ischemia. We sought to define the clinical and hemodynamic characteristics associated with CH. MATERIAL/METHODS: A retrospective cross sectional analysis was performed in which subjects were identified from our institutional cardiology database if echocardiography showed either right ventricular (RV) hypokinesis or dilatation, and was performed within 30 days of right heart catheterization. A chart review was then performed to identify patient clinical characteristics and to determine if the patients had underlying liver disease. Subjects with non-cardiac causes for hepatopathy were excluded. RESULTS: In 188 included subjects, etiology for right heart dysfunction included left heart failure (LHF), shunt, pulmonary hypertension, mitral- tricuspid- and pulmonic valvular disease. On multivariate analysis, higher RV diastolic pressure and etiology for RV dysfunction other than LHF were both associated with CH. Low cardiac output was associated with CH only amongst those without LHF. CONCLUSIONS: CH is most often seen in subjects with elevated RV diastolic pressure suggesting a congestive cause in most cases. CH associated with low cardiac output in patients without LHF suggests that low flow may be contributing to the patophysiology in some cases.


Assuntos
Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/etiologia , Hepatopatias/diagnóstico , Hepatopatias/etiologia , Hepatopatias/patologia , Idoso , Fosfatase Alcalina/sangue , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Estudos Transversais , Ecocardiografia , Feminino , Doenças das Valvas Cardíacas/complicações , Humanos , Hipertensão , Hipertensão Pulmonar/complicações , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
J Diabetes Metab Disord ; 20(1): 1011-1020, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34222096

RESUMO

PURPOSE: Designing mobile-based applications is one of the tools to raise the awareness of patients and the care team. Aim of this study is to identify the data elements of a mobile-based application to overweight and obesity management for children and adolescents from the experts' point of view. METHODS: In this descriptive-analytical article, data collection was conducted through library and Internet research. The research population comprised 30 nutritionists selected via simple sampling method. The research instrument was a questionnaire developed by the researcher in four sections: demographic data, assessment data, therapeutic recommendations and application capabilities. Validity and reliability were confirmed by Content Validity Ratio (CVR) and Delphi method respectively. RESULTS: The Minimum Data Set (MDS) required for overweight and obesity management in children and adolescents was designed based on the data from the guidelines of the United States, Canada, Australia, Britain, Iran, and experts' opinions. The importance of this MDS suggested was calculated based on the percentage points given by experts for the demographic data of 100%, the assessment data of 88.33%, the therapeutic recommendations of 97.67%, and the application capabilities of 88.94%. CONCLUSION: Identifying prevention and control minimum data set of overweight and obesity in children and adolescents from the point of view of experts will be effective in improving the applications in this field. This MDS has two parts of data elements: the first for recognition of the framework of evaluating and applying therapeutic methods that can empower parents to manage the child's body mass and the second as a patient's personal record for storage a set of data that can be used by nutritionists in visits to healthcare centers. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40200-021-00807-1.

17.
IUCrJ ; 7(Pt 6): 1102-1113, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33209321

RESUMO

An improved analysis for single-particle imaging (SPI) experiments, using the limited data, is presented here. Results are based on a study of bacteriophage PR772 performed at the Atomic, Molecular and Optical Science instrument at the Linac Coherent Light Source as part of the SPI initiative. Existing methods were modified to cope with the shortcomings of the experimental data: inaccessibility of information from half of the detector and a small fraction of single hits. The general SPI analysis workflow was upgraded with the expectation-maximization based classification of diffraction patterns and mode decomposition on the final virus-structure determination step. The presented processing pipeline allowed us to determine the 3D structure of bacteriophage PR772 without symmetry constraints with a spatial resolution of 6.9 nm. The obtained resolution was limited by the scattering intensity during the experiment and the relatively small number of single hits.

18.
Sci Data ; 7(1): 404, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214568

RESUMO

Single Particle Imaging (SPI) with intense coherent X-ray pulses from X-ray free-electron lasers (XFELs) has the potential to produce molecular structures without the need for crystallization or freezing. Here we present a dataset of 285,944 diffraction patterns from aerosolized Coliphage PR772 virus particles injected into the femtosecond X-ray pulses of the Linac Coherent Light Source (LCLS). Additional exposures with background information are also deposited. The diffraction data were collected at the Atomic, Molecular and Optical Science Instrument (AMO) of the LCLS in 4 experimental beam times during a period of four years. The photon energy was either 1.2 or 1.7 keV and the pulse energy was between 2 and 4 mJ in a focal spot of about 1.3 µm x 1.7 µm full width at half maximum (FWHM). The X-ray laser pulses captured the particles in random orientations. The data offer insight into aerosolised virus particles in the gas phase, contain information relevant to improving experimental parameters, and provide a basis for developing algorithms for image analysis and reconstruction.


Assuntos
Colífagos , Lasers , Aceleradores de Partículas , Vírion , Difração de Raios X
19.
Curr Gene Ther ; 9(1): 20-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19275568

RESUMO

AIDS is the result of infection by a lentivirus, HIV-1, which primarily infects CD4+ T cells and macrophages. There is presently no vaccine and none will be available in the foreseeable future. Highly active antiretroviral drug therapy has led to a dramatic reduction of viral load in many infected individuals, and has decreased mortality in the developing world. However, besides long-term drug toxicity and eventual emergence of drug-resistant strains, withdrawal from the therapy (even after effective and continuous treatment) results in re-emergence of the virus since cells harbouring the latent viral reservoirs persist. These issues highlight the need for alternative therapies, e.g. gene therapy. This review summarizes various gene therapy strategies that target early stages of HIV-1 life cycle. We will cover strategies that allow interference at the level of the released virion RNA, reverse transcriptase, pre-integration complex, integrase, dsDNA and provirus DNA in gene-modified cells.


Assuntos
DNA Viral/genética , Terapia Genética , Infecções por HIV/terapia , HIV-1/genética , Provírus/genética , Integração Viral/fisiologia , Infecções por HIV/genética , Infecções por HIV/virologia , Humanos
20.
J Appl Crystallogr ; 52(Pt 5): 997-1008, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31636518

RESUMO

The role of surface wetting properties and their impact on the performance of 3D printed microfluidic droplet generation devices for serial femtosecond crystallography (SFX) are reported. SFX is a novel crystallography method enabling structure determination of proteins at room temperature with atomic resolution using X-ray free-electron lasers (XFELs). In SFX, protein crystals in their mother liquor are delivered and intersected with a pulsed X-ray beam using a liquid jet injector. Owing to the pulsed nature of the X-ray beam, liquid jets tend to waste the vast majority of injected crystals, which this work aims to overcome with the delivery of aqueous protein crystal suspension droplets segmented by an oil phase. For this purpose, 3D printed droplet generators that can be easily customized for a variety of XFEL measurements have been developed. The surface properties, in particular the wetting properties of the resist materials compatible with the employed two-photon printing technology, have so far not been characterized extensively, but are crucial for stable droplet generation. This work investigates experimentally the effectiveness and the long-term stability of three different surface treatments on photoresist films and glass as models for our 3D printed droplet generator and the fused silica capillaries employed in the other fluidic components of an SFX experiment. Finally, the droplet generation performance of an assembly consisting of the 3D printed device and fused silica capillaries is examined. Stable and reproducible droplet generation was achieved with a fluorinated surface coating which also allowed for robust downstream droplet delivery. Experimental XFEL diffraction data of crystals formed from the large membrane protein complex photosystem I demonstrate the full compatibility of the new injection method with very fragile membrane protein crystals and show that successful droplet generation of crystal-laden aqueous droplets intersected by an oil phase correlates with increased crystal hit rates.

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