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1.
J Oncol Pharm Pract ; 29(1): 74-82, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34775858

RESUMO

INTRODUCTION: A paediatric cancer ward is a setting where pharmacists participate in direct patient care, acting as coordinators between the patient, caregivers and healthcare professionals. The aim of the study was to develop a Gap Finding Tool to support the setting up of a pharmaceutical care model at a Paediatric-Adolescent Cancer Ward. METHODS: The Standards of Practice for Clinical Pharmacy Services by the Society of Hospital Pharmacists of Australia Committee of Specialty Practice in Clinical Pharmacy (2013), the American College of Clinical Pharmacy (2014) and the European Association of Hospital Pharmacists (2014) were used to compile the Gap Finding Tool. The developed Tool was tested for content validity by a panel of experts and subsequently implemented over 2 months. RESULTS: The Gap Finding Tool comprised of nine sections with an average of eight statements each about pharmacy services that should be provided at ward level. For each statement, the rater indicates whether these contributions are provided. When the Tool was implemented at the Paediatric-Adolescent Cancer Ward, four major gaps were identified, namely, absence of a clinical pharmacist, lack of medicines information, vetting of chemotherapy prescriptions by pharmacist with limited access to patient data and lack of pharmacist-input on medicines availability. Processes requiring optimisation included discharge medication advice and documentation processes. CONCLUSION: The developed Gap Finding Tool is an innovative tool which is versatile and can be used in ward or ambulatory clinical settings to identify gaps in pharmaceutical processes and services and compare national or regional practices to international standards.


Assuntos
Serviço de Farmácia Hospitalar , Criança , Adolescente , Humanos , Farmacêuticos , Alta do Paciente , Hospitais , Austrália
2.
J Biol Chem ; 296: 100503, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33684444

RESUMO

G protein-coupled receptors (GPCRs) signal through activation of G proteins and subsequent modulation of downstream effectors. More recently, signaling mediated by ß-arrestin has also been implicated in important physiological functions. This has led to great interest in the identification of biased ligands that favor either G protein or ß-arrestin-signaling pathways. However, nearly all screening techniques for measuring ß-arrestin recruitment have required C-terminal receptor modifications that can in principle alter protein interactions and thus signaling. Here, we have developed a novel luminescence-based assay to measure ß-arrestin recruitment to the membrane or early endosomes by unmodified receptors. Our strategy uses NanoLuc, an engineered luciferase from Oplophorus gracilirostris (deep-sea shrimp) that is smaller and brighter than other well-established luciferases. Recently, several publications have explored functional NanoLuc split sites for use in complementation assays. We have identified a unique split site within NanoLuc and fused the corresponding N-terminal fragment to either a plasma membrane or early endosome tether and the C-terminal fragment to ß-arrestins, which form the basis for the MeNArC and EeNArC assays, respectively. Upon receptor activation, ß-arrestin is recruited to the membrane and subsequently internalized in an agonist concentration-dependent manner. This recruitment promotes complementation of the two NanoLuc fragments, thereby reconstituting functional NanoLuc, allowing for quantification of ß-arrestin recruitment with a single luminescence signal. Our assay avoids potential artifacts related to C-terminal receptor modification and has promise as a new generic assay for measuring ß-arrestin recruitment to diverse GPCR types in heterologous or native cells.


Assuntos
Membrana Celular/metabolismo , Luciferases/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , beta-Arrestinas/metabolismo , Bioensaio/métodos , Células Cultivadas , Humanos , Ligantes , Ligação Proteica , Transdução de Sinais , beta-Arrestinas/química
3.
Blood ; 136(2): 210-223, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32219444

RESUMO

Resistance to multimodal chemotherapy continues to limit the prognosis of acute lymphoblastic leukemia (ALL). This occurs in part through a process called adhesion-mediated drug resistance, which depends on ALL cell adhesion to the stroma through adhesion molecules, including integrins. Integrin α6 has been implicated in minimal residual disease in ALL and in the migration of ALL cells to the central nervous system. However, it has not been evaluated in the context of chemotherapeutic resistance. Here, we show that the anti-human α6-blocking Ab P5G10 induces apoptosis in primary ALL cells in vitro and sensitizes primary ALL cells to chemotherapy or tyrosine kinase inhibition in vitro and in vivo. We further analyzed the underlying mechanism of α6-associated apoptosis using a conditional knockout model of α6 in murine BCR-ABL1+ B-cell ALL cells and showed that α6-deficient ALL cells underwent apoptosis. In vivo deletion of α6 in combination with tyrosine kinase inhibitor (TKI) treatment was more effective in eradicating ALL than treatment with a TKI (nilotinib) alone. Proteomic analysis revealed that α6 deletion in murine ALL was associated with changes in Src signaling, including the upregulation of phosphorylated Lyn (pTyr507) and Fyn (pTyr530). Thus, our data support α6 as a novel therapeutic target for ALL.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Deleção de Genes , Integrina alfa6 , Proteínas de Neoplasias , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Pirimidinas/farmacologia , Animais , Anticorpos Antineoplásicos/farmacologia , Anticorpos Neutralizantes/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Integrina alfa6/genética , Integrina alfa6/metabolismo , Masculino , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia
4.
J Bacteriol ; 203(23): e0029321, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34543106

RESUMO

FlhDC is a heterohexameric complex that acts as a master regulator of flagellar biosynthesis genes in numerous bacteria. Previous studies have identified a single flhDC operon encoding this complex. However, we found that two flhDC loci are present throughout Paraburkholderia, and two additional flhC copies are also present in Paraburkholderia unamae. Systematic deletion analysis in P. unamae of the different flhDC copies showed that one of the operons, flhDC1, plays the predominant role, with deletion of its genes resulting in a severe inhibition of motility and biofilm formation. Expression analysis using promoter-lacZ fusions and real-time quantitative PCR support the primary role of flhDC1 in flagellar gene regulation, with flhDC2 a secondary contributor. Phylogenetic analysis shows the presence of the flhDC1 and flhDC2 operons throughout Paraburkholderia. In contrast, Burkholderia and other bacteria only carry the copy syntenous with flhDC2. The variations in impact each copy of flhDC has on downstream processes indicate that regulation of FlhDC in P. unamae, and likely other Paraburkholderia species, is regulated at least in part by the presence of multiple copies of these genes. IMPORTANCE Motility is important in the colonization of plant roots by beneficial and pathogenic bacteria, with flagella playing essential roles in host cell adhesion, entrance, and biofilm formation. Flagellar biosynthesis is energetically expensive. Its complex regulation by the FlhDC master regulator is well studied in peritrichous flagella expressing enterics. We report the unique presence throughout Paraburkholderia of multiple copies of flhDC. In P. unamae, the flhDC1 copy showed higher expression and a greater effect on swim motility, flagellar development, and regulation of downstream genes, than the flhDC2 copy that is syntenous to flhDC in Escherichia coli and pathogenic Burkholderia spp. The flhDC genes have evolved differently in these plant-growth-promoting bacteria, giving an additional layer of complexity in gene regulation by FlhDC.


Assuntos
Proteínas de Bactérias/metabolismo , Burkholderiaceae/metabolismo , Flagelos/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Movimento/fisiologia , Transativadores/metabolismo , Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Burkholderiaceae/genética , Flagelos/genética , Dosagem de Genes , Transativadores/genética
6.
Muscle Nerve ; 60(4): 464-473, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31323135

RESUMO

INTRODUCTION: Dysferlin loss-of-function mutations cause muscular dystrophy, accompanied by impaired membrane repair and muscle weakness. Growth promoting strategies including insulin-like growth factor 1 (IGF-1) could provide benefit but may cause strength loss or be ineffective. The objective of this study was to determine whether locally increased IGF-1 promotes functional muscle hypertrophy in dysferlin-null (Dysf-/- ) mice. METHODS: Muscle-specific transgenic expression and postnatal viral delivery of Igf1 were used in Dysf-/- and control mice. Increased IGF-1 levels were confirmed by enzyme-linked immunosorbent assay. Testing for skeletal muscle mass and function was performed in male and female mice. RESULTS: Muscle hypertrophy occurred in response to increased IGF-1 in mice with and without dysferlin. Male mice showed a more robust response compared with females. Increased IGF-1 did not cause loss of force per cross-sectional area in Dysf-/- muscles. DISCUSSION: We conclude that increased local IGF-1 promotes functional hypertrophy when dysferlin is absent and reestablishes IGF-1 as a potential therapeutic for dysferlinopathies.


Assuntos
Disferlina/genética , Fator de Crescimento Insulin-Like I/genética , Músculo Esquelético/metabolismo , Animais , Diafragma/metabolismo , Diafragma/patologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Músculo Esquelético/patologia , Distrofias Musculares/genética , Tamanho do Órgão
7.
Mol Ther ; 26(6): 1581-1593, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29673930

RESUMO

Most genetically distinct inherited retinal degenerations are primary photoreceptor degenerations. We selected a severe early onset form of Leber congenital amaurosis (LCA), caused by mutations in the gene LCA5, in order to test the efficacy of gene augmentation therapy for a ciliopathy. The LCA5-encoded protein, Lebercilin, is essential for the trafficking of proteins and vesicles to the photoreceptor outer segment. Using the AAV serotype AAV7m8 to deliver a human LCA5 cDNA into an Lca5 null mouse model of LCA5, we show partial rescue of retinal structure and visual function. Specifically, we observed restoration of rod-and-cone-driven electroretinograms in about 25% of injected eyes, restoration of pupillary light responses in the majority of treated eyes, an ∼20-fold decrease in target luminance necessary for visually guided behavior, and improved retinal architecture following gene transfer. Using LCA5 patient-derived iPSC-RPEs, we show that delivery of the LCA5 cDNA restores lebercilin protein and rescues cilia quantity. The results presented in this study support a path forward aiming to develop safety and efficacy trials for gene augmentation therapy in human subjects with LCA5 mutations. They also provide the framework for measuring the effects of intervention in ciliopathies and other severe, early-onset blinding conditions.


Assuntos
Cegueira/metabolismo , Cegueira/terapia , Dependovirus/genética , Terapia Genética/métodos , Animais , Eletrorretinografia , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Feminino , Humanos , Amaurose Congênita de Leber/metabolismo , Amaurose Congênita de Leber/terapia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo
8.
PLoS Pathog ; 12(12): e1006046, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27923070

RESUMO

Dynamic regulation of leukocyte population size and activation state is crucial for an effective immune response. In malaria, Plasmodium parasites elicit robust host expansion of macrophages and monocytes, but the underlying mechanisms remain unclear. Here we show that myeloid expansion during P. chabaudi infection is dependent upon both CD4+ T cells and the cytokine Macrophage Colony Stimulating Factor (MCSF). Single-cell RNA-Seq analysis on antigen-experienced T cells revealed robust expression of Csf1, the gene encoding MCSF, in a sub-population of CD4+ T cells with distinct transcriptional and surface phenotypes. Selective deletion of Csf1 in CD4+ cells during P. chabaudi infection diminished proliferation and activation of certain myeloid subsets, most notably lymph node-resident CD169+ macrophages, and resulted in increased parasite burden and impaired recovery of infected mice. Depletion of CD169+ macrophages during infection also led to increased parasitemia and significant host mortality, confirming a previously unappreciated role for these cells in control of P. chabaudi. This work establishes the CD4+ T cell as a physiologically relevant source of MCSF in vivo; probes the complexity of the CD4+ T cell response during type 1 infection; and delineates a novel mechanism by which T helper cells regulate myeloid cells to limit growth of a blood-borne intracellular pathogen.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Fator Estimulador de Colônias de Macrófagos/biossíntese , Fator Estimulador de Colônias de Macrófagos/imunologia , Malária/imunologia , Animais , Linfócitos T CD4-Positivos/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Imunofluorescência , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Plasmodium chabaudi/imunologia , Reação em Cadeia da Polimerase
9.
Community Ment Health J ; 53(6): 688-694, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28540538

RESUMO

Interventions are needed to address frailty and other behaviors (e.g., drug and alcohol use) among prefrail and frail homeless women (P/FHW). The purpose of this pilot randomized controlled trial (RCT) was to compare the efficacy of a Frailty Intervention (FI) versus a Health Promotion (HP) program among P/FHW (N = 32). Structured instruments assessed sociodemographics, individual, situational, health-related, and behavioral factors. While program differences were not statistically significant with the main outcome variables, medium-to-large effect sizes were found in favor of the HP program as it relates to physical and overall frailty, as well as, any drug use, alcohol use, and drug dependency. Based on these findings, it is critical to strengthen the HP program to optimize all domains of frailty (e.g., physical, psychological, and social) and substance use for P/FHW.


Assuntos
Fragilidade/prevenção & controle , Adulto , Idoso , Serviços de Saúde Comunitária/métodos , Feminino , Idoso Fragilizado , Promoção da Saúde/métodos , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Fatores de Risco
10.
Public Health Nurs ; 32(6): 634-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25832775

RESUMO

OBJECTIVES: Middle-aged and older homeless women have unique health and social service delivery needs; yet, limited research has been conducted in this area. The purpose of this study was to assess perspectives among prefrail and frail, middle-aged and older homeless women. DESIGN AND SAMPLE: Focus group methodology was conducted to assess perspectives among these homeless women (N=20) aged 43 to 62. MEASURES: Sociodemographic and frailty characteristics were assessed by structured instruments, along with mobility, assistive device use and falls. RESULTS: The average age was 53.4; the majority of the sample was African-American (70%). In total, 60% reported living in a shelter for the last 30 days, while 20% were unsheltered. The majority of the sample reported walking independently (80%) and not using an assistive device (65%). Over one third (35%) fell in the last 30 days and 70% fell in the last year. Content analysis revealed several themes that included (1) health care needs and challenges experienced; (2) perspectives on sexual decision making; (3) employment difficulties; (4) existing support systems; and (5) development of future program planning. CONCLUSIONS: Future research development and implications are discussed.


Assuntos
Necessidades e Demandas de Serviços de Saúde , Pessoas Mal Alojadas/psicologia , Adulto , Feminino , Grupos Focais , Pessoas Mal Alojadas/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Enfermagem em Saúde Pública , Pesquisa Qualitativa
11.
Cells ; 13(2)2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38247839

RESUMO

Traumatic Brain Injury (TBI) represents a significant health concern, necessitating advanced therapeutic interventions. This detailed review explores the critical roles of astrocytes, key cellular constituents of the central nervous system (CNS), in both the pathophysiology and possible rehabilitation of TBI. Following injury, astrocytes exhibit reactive transformations, differentiating into pro-inflammatory (A1) and neuroprotective (A2) phenotypes. This paper elucidates the interactions of astrocytes with neurons, their role in neuroinflammation, and the potential for their therapeutic exploitation. Emphasized strategies encompass the utilization of endocannabinoid and calcium signaling pathways, hormone-based treatments like 17ß-estradiol, biological therapies employing anti-HBGB1 monoclonal antibodies, gene therapy targeting Connexin 43, and the innovative technique of astrocyte transplantation as a means to repair damaged neural tissues.


Assuntos
Lesões Encefálicas Traumáticas , Medicina , Humanos , Astrócitos , Lesões Encefálicas Traumáticas/terapia , Sistema Nervoso Central , Anticorpos Monoclonais
12.
Cell Death Discov ; 10(1): 305, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942762

RESUMO

This study assesses the neuroprotective potential of CPP-P1, a conjugate of an anti-apoptotic peptain-1 (P1) and a cell-penetrating peptide (CPP) in in vitro, in vivo, and ex vivo glaucoma models. Primary retinal ganglion cells (RGCs) were subjected to either neurotrophic factor (NF) deprivation for 48 h or endothelin-3 (ET-3) treatment for 24 h and received either CPP-P1 or vehicle. RGC survival was analyzed using a Live/Dead assay. Axotomized human retinal explants were treated with CPP-P1 or vehicle for seven days, stained with RGC marker RBPMS, and RGC survival was analyzed. Brown Norway (BN) rats with elevated intraocular pressure (IOP) received weekly intravitreal injections of CPP-P1 or vehicle for six weeks. RGC function was evaluated using a pattern electroretinogram (PERG). RGC and axonal damage were also assessed. RGCs from ocular hypertensive rats treated with CPP-P1 or vehicle for seven days were isolated for transcriptomic analysis. RGCs subjected to 48 h of NF deprivation were used for qPCR target confirmation. NF deprivation led to a significant loss of RGCs, which was markedly reduced by CPP-P1 treatment. CPP-P1 also decreased ET-3-mediated RGC death. In ex vivo human retinal explants, CPP-P1 decreased RGC loss. IOP elevation resulted in significant RGC loss in mid-peripheral and peripheral retinas compared to that in naive rats, which was significantly reduced by CPP-P1 treatment. PERG amplitude decline in IOP-elevated rats was mitigated by CPP-P1 treatment. Following IOP elevation in BN rats, the transcriptomic analysis showed over 6,000 differentially expressed genes in the CPP-P1 group compared to the vehicle-treated group. Upregulated pathways included CREB signaling and synaptogenesis. A significant increase in Creb1 mRNA and elevated phosphorylated Creb were observed in CPP-P1-treated RGCs. Our study showed that CPP-P1 is neuroprotective through CREB signaling enhancement in several settings that mimic glaucomatous conditions. The findings from this study are significant as they address the pressing need for the development of efficacious therapeutic strategies to maintain RGC viability and functionality associated with glaucoma.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38487870

RESUMO

AIMS: Embolic Stroke of Undetermined Source (ESUS) results in significant morbidity. A left atrial (LA) myopathy is implicated in a proportion of these patients. We hypothesized that LA shape varies by cause of stroke (cardioembolic versus ESUS). METHODS AND RESULTS: 236 ischemic stroke, atrial fibrillation (AF) patients and controls were recruited prospectively. AF was classified as paroxysmal (PAF) or persistent AF (PersAF). Stroke patients comprised cardioembolic stroke (CE) secondary to AF and ESUS. There were 81 AF (47 PAF, 34 PersAF), 50 ESUS, 57 CE patients (subdivided into CE with PAF (CEpaf) and CE with PersAF (CEpers) and 48 controls. Echocardiographic parameters including LA volume, function, and shape/sphericity (3D LA-sphericity and 2D-derived LA-circularity, ellipticity, sphericity and eccentricity indices) were evaluated. Increased LA volume and sphericity with LA dysfunction was present in CE, AF and ESUS groups compared to controls. K-means cluster analysis demonstrated a spectrum of LA myopathy with controls at the lowest and CEpers and PersAF at the upper extremes, with ESUS, PAF and CEpaf being similar and falling between these extremes. After adjusting for age, sex and left ventricular (LV) and LA parameters, LA sphericity markers differentiated ESUS from controls (p < 0.01). CONCLUSIONS: Alterations in LA shape are present in ESUS, AF and CE patients, particularly increased spherical remodelling. The novel markers of LA sphericity proposed may identify LA myopathy in ESUS patients and potentially guide management for secondary prevention.

14.
Front Neurosci ; 17: 1198343, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37250427

RESUMO

Glaucoma is a leading cause of blindness worldwide, commonly associated with elevated intraocular pressure (IOP), leading to degeneration of the optic nerve and death of retinal ganglion cells, the output neurons in the eye. In recent years, many studies have implicated mitochondrial dysfunction as a crucial player in glaucomatous neurodegeneration. Mitochondrial function has been an increasingly researched topic in glaucoma, given its vital role in bioenergetics and propagation of action potentials. One of the most metabolically active tissues in the body characterized by high oxygen consumption is the retina, particularly the retinal ganglion cells (RGCs). RGCs, which have long axons that extend from the eyes to the brain, rely heavily on the energy generated by oxidative phosphorylation for signal transduction, rendering them more vulnerable to oxidative damage. In various glaucoma models, mitochondrial dysfunction and stress from protein aggregates in the endoplasmic reticulum (ER) have been observed in the RGCs. However, it has been shown that the two organelles are connected through a network called mitochondria-associated ER membranes (MAMs); hence this crosstalk in a pathophysiological condition such as glaucoma should be evaluated. Here, we review the current literature suggestive of mitochondrial and ER stress related to glaucoma, indicating potential cross-signaling and the potential roles of MAMs.

15.
Gastroenterol Res Pract ; 2023: 5982580, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38107205

RESUMO

Background. Iron deficiency (ID) is a common micronutrient deficiency and the leading cause of anemia worldwide. ID can be caused by chronic occult blood loss from colorectal neoplasia including colorectal cancer (CRC) and advanced precancerous colorectal lesions. Current guidelines recommend colonoscopy in both men and postmenopausal women presenting with ID anemia (IDA). However, there is controversy on the investigation of patients presenting with a lower risk of CRC including younger women with ID and those with nonanemic ID (NAID). There is a need for a triaging tool to identify which ID patients may benefit from colonoscopy. The fecal immunochemical test (FIT) is sensitive for CRC screening in an asymptomatic population, but its role in ID patients is unclear. The aim of this study is to conduct a systematic review to determine the diagnostic accuracy of FIT for detecting CRC and advanced precancerous neoplasia in individuals presenting with ID with or without anemia. Methods and Analysis. This protocol conforms with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols and Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy. A comprehensive search of the MEDLINE, Embase, and Web of Science databases will be undertaken for studies published after 2010 which involve patients with ID, who completed a FIT in the 6 months prior to colonoscopy, with FIT sensitivity and specificity calculated against the reference standard colonoscopy. The search will be limited to studies conducted after 2010 to reduce variability in colonoscopy quality. Risk of bias assessment will be conducted using the Quality Assessment of Diagnostic Accuracy Studies version 2. FIT sensitivity and specificity will be the primary measure of diagnostic accuracy, and data will be analysed using a random effects meta-analysis. Discussion. This review and meta-analysis will be the first to systematically explore the value of the FIT as a triaging tool for patients with ID. This trial is registered with CRD42022367162.

16.
Sci Rep ; 13(1): 12428, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528139

RESUMO

Cancer is a significant healthcare issue, and early screening methods based on biomarker analysis in liquid biopsies are promising avenues to reduce mortality rates. Electrical detection of nucleic acids at the single molecule level could enable these applications. We examine the electrical detection of RNA cancer biomarkers (KRAS mutants G12C and G12V) as a single-molecule proof-of-concept electrical biosensor for cancer screening applications. We show that the electrical conductance is highly sensitive to the sequence, allowing discrimination of the mutants from a wild-type KRAS sequence differing in just one base. In addition to this high specificity, our results also show that these biosensors are sensitive down to an individual molecule with a high signal-to-noise ratio. These results pave the way for future miniaturized single-molecule electrical biosensors that could be groundbreaking for cancer screening and other applications.


Assuntos
Técnicas Biossensoriais , Neoplasias , Ácidos Nucleicos , Humanos , RNA , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias/diagnóstico , Neoplasias/genética , Técnicas Biossensoriais/métodos , Biomarcadores
17.
Front Immunol ; 14: 1143012, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143657

RESUMO

Introduction: Plasmodium sporozoites (SPZ) inoculated by Anopheles mosquitoes into the skin of the mammalian host migrate to the liver before infecting hepatocytes. Previous work demonstrated that early production of IL-6 in the liver is detrimental for the parasite growth, contributing to the acquisition of a long-lasting immune protection after immunization with live attenuated parasites. Methods: Considering that IL-6 as a critical pro-inflammatory signal, we explored a novel approach whereby the parasite itself encodes for the murine IL-6 gene. We generated transgenic P. berghei parasites that express murine IL-6 during liver stage development. Results and Discussion: Though IL-6 transgenic SPZ developed into exo-erythrocytic forms in hepatocytes in vitro and in vivo, these parasites were not capable of inducing a blood stage infection in mice. Furthermore, immunization of mice with transgenic IL-6-expressing P. berghei SPZ elicited a long-lasting CD8+ T cell-mediated protective immunity against a subsequent infectious SPZ challenge. Collectively, this study demonstrates that parasite-encoded IL-6 attenuates parasite virulence with abortive liver stage of Plasmodium infection, forming the basis of a novel suicide vaccine strategy to elicit protective antimalarial immunity.


Assuntos
Hepatopatias , Vacinas Antimaláricas , Animais , Camundongos , Linfócitos T CD8-Positivos , Interleucina-6 , Mamíferos , Plasmodium berghei
18.
Artigo em Inglês | MEDLINE | ID: mdl-38464735

RESUMO

Glaucoma is a chronic and progressive eye disease, commonly associated with elevated intraocular pressure (IOP) and characterized by optic nerve degeneration, cupping of the optic disc, and loss of retinal ganglion cells (RGCs). The pathological changes in glaucoma are triggered by multiple mechanisms and both mechanical effects and vascular factors are thought to contribute to the etiology of glaucoma. Various studies have shown that endothelin-1 (ET-1), a vasoactive peptide, acting through its G protein coupled receptors, ETA and ETB, plays a pathophysiologic role in glaucoma. However, the mechanisms by which ET-1 contribute to neurodegeneration remain to be completely understood. Our laboratory and others demonstrated that macitentan (MAC), a pan endothelin receptor antagonist, has neuroprotective effects in rodent models of IOP elevation. The current study aimed to determine if oral administration of a dual endothelin antagonist, macitentan, could promote neuroprotection in an acute model of intravitreal administration of ET-1. We demonstrate that vasoconstriction following the intravitreal administration of ET-1 was attenuated by dietary administration of the ETA/ETB dual receptor antagonist, macitentan (5 mg/kg body weight) in retired breeder Brown Norway rats. ET-1 intravitreal injection produced a 40% loss of RGCs, which was significantly lower in macitentan-treated rats. We also evaluated the expression levels of glial fibrillary acidic protein (GFAP) at 24 h and 7 days post intravitreal administration of ET-1 in Brown Norway rats as well as following ET-1 treatment in cultured human optic nerve head astrocytes. We observed that at the 24 h time point the expression levels of GFAP was upregulated (indicative of glial activation) following intravitreal ET-1 administration in both retina and optic nerve head regions. However, following macitentan administration for 7 days after intravitreal ET-1 administration, we observed an upregulation of GFAP expression, compared to untreated rats injected intravitreally with ET-1 alone. Macitentan treatment in ET-1 administered rats showed protection of RGC somas but was not able to preserve axonal integrity and functionality. The endothelin receptor antagonist, macitentan, has neuroprotective effects in the retinas of Brown Norway rats acting through different mechanisms, including enhancement of RGC survival and reduction of ET-1 mediated vasoconstriction.

19.
Exp Cell Res ; 317(3): 356-66, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21070767

RESUMO

In a previous study investigating the effects of low temperature on skeletal muscle differentiation, we demonstrated that C2C12 mouse myoblasts cultured at 30°C do not express myogenin, a myogenic regulatory factor (MRF), or fuse into multinucleated myotubes. At this low temperature, the myoblasts continuously express Id3, a negative regulator of MRFs, and do not upregulate muscle-specific microRNAs. In this study, we examined if insulin-like growth factor-I (IGF-I) and a stable form of vitamin C (L-ascorbic acid phosphate) could alleviate the low temperature-induced inhibition of myogenic differentiation in C2C12 cells. Although the addition of either IGF-I or vitamin C alone could promote myogenin expression in C2C12 cells at 30°C, elongated multinucleated myotubes were not formed unless both IGF-I and vitamin C were continuously administered. In human skeletal muscle cells, low temperature-induced blockage of myogenic differentiation was also ameliorated by exogenous IGF-I and vitamin C. In addition, we demonstrated that satellite cells of IGF-I overexpressing transgenic mice in single-fiber culture expressed myogenin at a higher level than those of wild-type mice at 30°C. This study suggests that body temperature plays an important role in myogenic differentiation of endotherms, but the sensitivity to low temperature could be buffered by certain factors in vivo, such as IGF-I and vitamin C.


Assuntos
Ácido Ascórbico/farmacologia , Diferenciação Celular/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Músculo Esquelético/citologia , Miogenina/farmacologia , Animais , Temperatura Corporal , Linhagem Celular , Temperatura Baixa , Humanos , Camundongos , Fibras Musculares Esqueléticas/citologia , Células Satélites de Músculo Esquelético/citologia
20.
J Pediatr Pharmacol Ther ; 27(2): 180-191, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35241991

RESUMO

We present the case of a breast-fed preterm infant with postnatally acquired cytomegalovirus (CMV) and severe necrotizing enterocolitis (NEC) associated with CMV. The infant had persistent severe thrombocytopenia with clinical deterioration despite multiple platelet transfusions and maximal medical treatment. Surgical intervention was not feasible owing to the instability of the infant's condition. Upon identification of CMV in urine, intravenous ganciclovir was initiated with significant clinical improvement. We also present a literature review of cases of CMV-related NEC or other gastrointestinal complications in preterm and term infants.

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