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Interstitial cystitis (IC), also called painful bladder syndrome (PBS), is 2 to 5 times more common in women than in men, yet its cause and pathogenesis remain unclear. In our study using the cyclophosphamide (CYP)-induced mouse model of cystitis, histological evaluation of the urinary bladder (UB) lamina propria (LP) showed immune cell infiltrations, indicating moderate to severe inflammation. In this study, we noticed a differential expression of a subset of microRNAs (miRs) in the UB cells (UBs) of CYP-induced cystitis as compared to the control. UB inflammatory scores and inflammatory signaling were also elevated in CYP-induced cystitis as compared to control. We identified eight UBs miRs that exhibited altered expression after CYP induction and are predicted to have a role in inflammation and smooth muscle function (miRs-34c-5p, -34b-3p, -212-3p, -449a-5p, -21a-3p, -376b-3p, -376b-5p and - 409-5p). Further analysis using ELISA for inflammatory markers and real-time PCR (RT-PCR) for differentially enriched miRs identified miR-34c as a potential target for the suppression of UB inflammation in cystitis. Blocking miR-34c by antagomir ex vivo reduced STAT3, TGF-ß1, and VEGF expression in the UBs, which was induced during cystitis as compared to control. Interestingly, miR-34c inhibition also downregulated ROCK2 but elevated ROCK1 expression in bladder and detrusor cells. Thus, the present study shows that targeting miR-34c can mitigate the STAT3, TGF-ß, and VEGF, inflammatory signaling in UB, and suppress ROCK2 expression in UBs to effectively suppress the inflammatory response in cystitis. This study highlights miR-34c as a potential biomarker and/or serves as the basis for new therapies for the treatment of cystitis.
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Cistite Intersticial , Cistite , MicroRNAs , Masculino , Camundongos , Animais , Humanos , Feminino , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cistite/induzido quimicamente , Bexiga Urinária/metabolismo , Cistite Intersticial/genética , Cistite Intersticial/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Ciclofosfamida/efeitos adversos , Inflamação/metabolismo , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismoRESUMO
The lymphatic network is pivotal for various physiological functions in the human body. Accumulated evidence supports the role of therapeutic lymphangiogenesis in the treatment of several pathologies. Endogenous gasotransmitter, hydrogen sulfide (H2S) has been extensively studied for its potential as a pro-angiogenic factor and vascular function modulator. However, the role of H2S in governing lymphatic vessel formation, and underlying molecular mechanisms are understudied. The present study was designed to investigate the effects of H2S donor sodium hydrogen sulfide (NaHS) on lymphatic vascularization and pro-angiogenic signaling pathways using both in vitro and in vivo approaches. In vitro dose-response experiments showed increased proliferation and tube formation by NaHS-treated human lymphatic endothelial cells (LECs) compared with control cells. Immunoblotting performed with LEC lysates prepared after time-course NaHS treatment demonstrated increased activation of ERK1/2, AKT and eNOS after 20 min of NaHS stimulation. Further, NaHS treatment induced nitric oxide production, reduced reactive oxygen species generation, and promoted cell cycle in LECs. Additional cell cycle analysis showed that NaHS treatment abrogates oxidized LDL-induced cell cycle arrest in LECs. The results of in vivo Matrigel plug assay revealed increased lymphatic vessel density in Matrigel plugs containing NaHS compared with control plugs, however, no significant differences in angiogenesis and immune cell infiltration were observed. Collectively, these findings suggest that H2S donor NaHS promotes lymphatic vessel formation both in vitro and in vivo and may be utilized to promote reparative lymphangiogenesis to alleviate lymphatic dysfunction-related disorders.
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Sulfeto de Hidrogênio , Vasos Linfáticos , Humanos , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Endoteliais/metabolismo , Linfangiogênese , Vasos Linfáticos/metabolismoRESUMO
Individuals with sickle cell disease (SCD) are at greater risk of rhabdomyolysis, a potentially life-threatening condition resulting from the breakdown of skeletal muscle fibers. Acute kidney injury (AKI) is one of the most severe complications of rhabdomyolysis. Chronic kidney and cardiovascular disease, which account for SCD mortality, are long-term consequences of AKI. Although SCD elevates the risks of rhabdomyolysis-induced sudden death, the mechanisms that underlie rhabdomyolysis-induced AKI in SCD are unclear. In the present study, we show that, unlike their control non-sickling (AA) counterparts, transgenic homozygous SCD (SS; Townes model) mice exhibited 100% mortality 8-24 h after intramuscular glycerol injection. Five hours after glycerol injection, SS mice showed a more significant increase in myoglobinuria and plasma creatine kinase levels than AA mice. Basal plasma heme and kidney tissue iron levels were significantly higher in SS than in AA mice. In contrast to AA, glycerol-induced rhabdomyolysis aggravated these parameters in SS mice. Rhabdomyolysis also amplified oxidative stress in SS compared to AA mice. Glycerol-treated SS mice exhibited worse renal function, exemplified by a reduction in GFR with a corresponding increase in plasma and urinary biomarkers of early AKI and renal tubular damage. The free radical scavenger and Fenton chemistry inhibitor, TEMPOL, ameliorated rhabdomyolysis-induced AKI in the SS mice. These findings demonstrate that oxidative stress driven by renal iron accumulation amplifies rhabdomyolysis-induced AKI in SCD mice.
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Injúria Renal Aguda , Anemia Falciforme , Rabdomiólise , Camundongos , Animais , Glicerol/efeitos adversos , Apoptose , Rim , Injúria Renal Aguda/induzido quimicamente , Rabdomiólise/complicações , Rabdomiólise/induzido quimicamente , Rabdomiólise/metabolismo , Anemia Falciforme/complicações , FerroRESUMO
Tubular epithelial cell fate following exposure to various types of injurious stimuli can be decided at distinct cell cycle checkpoints. One such checkpoint occurs during mitosis, known as the spindle assembly checkpoint, and is tightly regulated through the actions of cell division cycle protein 20 (CDC20). Due to our paucity of knowledge about the role of CDC20 in the kidney, the present study was designed to investigate the expression levels and distribution of CDC20 within the kidney and how pharmacological inhibition of CDC20 function affects kidney recovery using various rodent models of kidney injury. CDC20 is normally detected in distal tubules, but upon injury by either cisplatin administration or ureter obstruction, CDC20 accumulation is considerably elevated. Blockade of CDC20 activity using a selective pharmacological inhibitor, Apcin, lowered serum creatinine, tubular damage, and DNA injury following acute kidney injury compared with vehicle-treated mice. In unilateral ureteral obstruction, Apcin reduced tissue kidney injury molecule-1 levels, sirius red staining, and tubulointerstitial α-smooth muscle actin staining in the tissue. The findings in the present study demonstrated that elevations in CDC20 levels in the kidney are associated with kidney injury and that inhibition of CDC20 can alleviate and reverse some of the pathological effects on the architecture and function of kidney.NEW & NOTEWORTHY To our knowledge, this is the first study to characterize the expression and localization of cell division cycle 20 protein (CDC20) in normal and acute, and chronically injured kidneys. Tubular epithelial cell damage was markedly reduced through the administration of a selective inhibitor of CDC20, Apcin. This study provides new evidence that CDC20 can be induced in damaged kidney cells and negatively impact the recovery of the kidney following acute kidney injury.
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Injúria Renal Aguda , Obstrução Ureteral , Camundongos , Animais , Proteínas de Ciclo Celular/metabolismo , Rim/metabolismo , Carbamatos/farmacologia , Obstrução Ureteral/complicações , Injúria Renal Aguda/complicaçõesRESUMO
BACKGROUND: TSP1 (thrombospondin-1)-a well-known angiogenesis inhibitor-mediates differential effects via interacting with cell surface receptors including CD36 (cluster of differentiation) and CD47. However, the role of TSP1 in regulating lymphangiogenesis is not clear. Our previous study suggested the importance of cell-specific CD47 blockade in limiting atherosclerosis. Further, our experiments revealed CD47 as a dominant TSP1 receptor in lymphatic endothelial cells (LECs). As the lymphatic vasculature is functionally linked to atherosclerosis, we aimed to investigate the effects of LEC TSP1-CD47 signaling inhibition on lymphangiogenesis and atherosclerosis. METHODS: Murine atherosclerotic and nonatherosclerotic arteries were utilized to investigate TSP1 expression using Western blotting and immunostaining. LEC-specific knockout mice were used to determine the in vivo role of LEC Cd47 in lymphangiogenesis and atherosclerosis. Various in vitro cell-based assays, in vivo Matrigel plug implantation, molecular biological techniques, and immunohistological approaches were used to evaluate the underlying signaling mechanisms. RESULTS: Elevated TSP1 expression was observed in mouse atherosclerotic aortic tissue compared with nonatherosclerotic control tissue. TSP1 at pathological concentrations suppressed both in vitro and in vivo lymphangiogenesis. Mechanistically, TSP1 inhibited VEGF (vascular endothelial growth factor)-C-induced AKT and eNOS activation in LEC and attenuated NO (nitric oxide) production. Further, CD47 silencing in LEC prevented the effects of TSP1 on lymphangiogenic AKT-eNOS signaling and lymphangiogenesis. Atheroprone AAV (adeno-associated virus) 8-PCSK9-injected LEC-specific Cd47 knockout mice (Cd47ΔLEC) had reduced atherosclerosis in both aorta and aortic root compared with control mice (Cd47ΔWT). However, no differences in metabolic parameters including body weight, plasma total cholesterol levels, and fasting blood glucose were observed. Additional immunostaining experiments performed on aortic root cross-sections indicated higher lymphatic vessel density in Cd47ΔLEC mice in comparison to controls. CONCLUSIONS: These findings demonstrate that TSP1 inhibits lymphangiogenesis via activation of CD47 in LEC, and loss of LEC Cd47 attenuates atherosclerotic lesion formation. Collectively, these results identify LEC CD47 as a potential therapeutic target in atherosclerosis.
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Aterosclerose , Células Endoteliais , Animais , Camundongos , Aterosclerose/genética , Aterosclerose/prevenção & controle , Aterosclerose/metabolismo , Antígeno CD47/genética , Antígeno CD47/metabolismo , Células Endoteliais/metabolismo , Linfangiogênese , Camundongos Knockout , Pró-Proteína Convertase 9/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Trombospondina 1/genética , Trombospondina 1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The beneficial effects of the polyphenolic compound piceatannol (PC) has been reported for metabolic diseases, antiproliferative, antioxidant, and anti-cancer properties. Despite its beneficial effects on inflammatory diseases, little is known about how PC regulates inflammatory responses and adipogenesis. Therefore, this study was designed to determine the effects of PC on the inflammatory response and adipogenesis. The effect of PC on splenocytes, 3T3-L1 adipocytes, and RAW264.7 macrophages was analyzed by flow cytometry, qRT-PCR, morphometry, and western blot analysis. PC induced apoptosis in activated T cells in a dose-dependent manner using stimulated splenocytes and reduced the activation of T cells, altered T cell frequency, and interestingly induced the frequency of regulatory T (Treg) cells as compared to controls. PC suppressed the expression of TNF-α, iNOS, IL-6R, and NF-κB activation in RAW264.7 macrophages after lipopolysaccharides (LPS)-induction as compared to the control. Interestingly, PC altered the cell morphology of 3T3-L1 adipocytes with a concomitant decrease in cell volume, lipid deposition, and TNF-α expression, but upregulation of leptin and IL-1ß. Our findings suggested that PC induced apoptosis in activated T cells, decreased immune cell activation and inflammatory response, and hindered adipogenesis. This new set of data provides promising hope as a new therapeutic to treat both inflammatory disease and obesity.
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Adipogenia , Fator de Necrose Tumoral alfa , Camundongos , Animais , Fator de Necrose Tumoral alfa/metabolismo , Linfócitos T Reguladores/metabolismo , Transdução de Sinais , Células 3T3-L1 , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismoRESUMO
Background: The current social and legal landscape is likely to foster the medicinal and recreational use of cannabis. Synthetic cannabinoid use is associated with acute kidney injury (AKI) in case reports; however, the association between natural cannabis use and AKI risk in patients with advanced chronic kidney disease (CKD) is unknown. Materials and Methods: From a nationally representative cohort of 102,477 U.S. veterans transitioning to dialysis between 2007 and 2015, we identified 2215 patients with advanced CKD who had undergone urine toxicology (UTOX) tests within a year before dialysis initiation and had inpatient serial serum creatinine levels measured within 7 days after their UTOX test. The exposure of interest was cannabis use compared with no use as ascertained by the UTOX test. We examined the association of this exposure with AKI using logistic regression and inverse probability of treatment weighting with extensive adjustment for potential confounders. Results: The mean age of the overall cohort was 61 years; 97% were males, 51% were African Americans, 97% had hypertension, 76% had hyperlipidemia, and 75% were diabetic. AKI occurred in 56% of the cohort, and in multivariable-adjusted analysis, cannabis use (when compared with no substance use) was not associated with significantly higher odds of AKI (odds ratio 0.85, 95% confidence interval 0.38-1.87; p=0.7). These results were robust to various sensitivity analyses. Conclusions: In this observational study examining patients with advanced CKD, cannabis use was not associated with AKI risk. Additional studies are needed to characterize the impact of cannabis use on risk of kidney disease and injury.
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Injúria Renal Aguda , Cannabis , Insuficiência Renal Crônica , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Diálise Renal , Fatores de Risco , Estudos Retrospectivos , Insuficiência Renal Crônica/terapia , Injúria Renal Aguda/terapiaRESUMO
Background: Kidney fibrosis is a hallmark consequence of all forms of chronic kidney disease with few available treatment modalities. Material and Methods: In this study, we performed the unilateral ureteral obstruction (UUO) procedure to investigate the effects of a selective cannabinoid type 2 (CB2) agonist receptor, SMM-295, as a nephroprotective therapy. Results: SMM-295 was demonstrated to exhibit 50-fold selectivity over the cannabinoid type 1 (CB1) receptor with an EC50 â¼2 nM. Four other off-targets were identified in the safety panel, but only at the highest concentration (5 mM) tested in the assay demonstrating the relative selectivity and safety of our compound. Administration of SMM-295 (12 mg/kg IP daily) in UUO mice led to a significant decrease of 33% in tubular damage compared to the vehicle-treated UUO mice after 7 days. Consistent with these findings, there was a significant decrease in α-smooth muscle actin and fibronectin, which are markers of tubulointerstitial fibrosis, as determined by Western blot analysis. DNA damage as detected by a classic marker, γ-H2AX, was significantly reduced by 50% in the SMM-295 treatment group compared to vehicle treatment. Genetic knockout of CB2 or administration of a CB2 inverse agonist did not exhibit any beneficial effect on tubulointerstitial fibrosis or kidney tubule injury. Conclusions: In conclusion, our study provides new evidence that SMM-295 can therapeutically target the CB2 receptor with few, if any, physiological off-target sites to reduce kidney tissue damage and slow the fibrotic progression in a mouse model of kidney fibrosis.
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Canabinoides , Obstrução Ureteral , Humanos , Obstrução Ureteral/tratamento farmacológico , Receptores de Canabinoides , Canabinoides/farmacologia , Fibrose , RimRESUMO
CDC20 binds to anaphase-promoting complex/cyclosome E3 ubiquitin ligase to recruit substrates for ubiquitination to promote mitotic progression. In breast and other cancers, CDC20 overexpression causes cell cycle dysregulation and is associated with poor prognosis. Apcin was previously discovered as a CDC20 inhibitor exhibiting high micromolar activities. Here, we designed and developed new apcin-based inhibitors by eliminating a controlled substance, chloral hydrate, required for synthesis. We further improved the antitumor activities of the inhibitors by replacing the pyrimidine group with substituted thiazole-containing groups. When evaluated in MDA-MB-231 and MDA-MB-468 triple negative breast cancer cell lines, several analogs showed 5-10-fold improvement over apcin with IC50 values at â¼10 µM in cell viability assays. Tubulin polymerization assay showed our CDC20 inhibitors had no off-target effects against tubulin. Proapoptotic Bim accumulation was detected in our CDC20 inhibitor treated MDA-MB-468 cells. The most effective inhibitors, 22, warrant further development to target CDC20 in diseases.
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Cisplatin is a commonly used chemotherapeutic agent to treat a wide array of cancers that is frequently associated with toxic injury to the kidney due to oxidative DNA damage and perturbations in cell cycle progression leading to cell death. In this study, we investigated whether thyroid receptor interacting protein 13 (TRIP13) plays a central role in the protection of the tubular epithelia following cisplatin treatment by circumventing DNA damage. Following cisplatin treatment, double-stranded DNA repair pathways were inhibited using selective blockers to proteins involved in either homologous recombination or non-homologous end joining. This led to increased blood markers of acute kidney injury (AKI) (creatinine and neutrophil gelatinase-associated lipocalin), tubular damage, activation of DNA damage marker (γ-H2AX), elevated appearance of G2/M blockade (phosphorylated histone H3 Ser10 and cyclin B1), and apoptosis (cleaved caspase-3). Conditional proximal tubule-expressing Trip13 mice were observed to be virtually protected from the cisplatin nephrotoxicity by restoring most of the pathological phenotypes back toward normal conditions. Our findings suggest that TRIP13 could circumvent DNA damage in the proximal tubules during cisplatin injury and that TRIP13 may constitute a new therapeutic target in protecting the kidney from nephrotoxicants and reduce outcomes leading to AKI.
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ATPases Associadas a Diversas Atividades Celulares/metabolismo , Injúria Renal Aguda/induzido quimicamente , Proteínas de Ciclo Celular/metabolismo , Cisplatino/efeitos adversos , Dano ao DNA/genética , Reparo do DNA/genética , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos TransgênicosRESUMO
Primitive-based models of motor learning suggest that adaptation occurs by tuning the responses of motor primitives. Based on this idea, we consider motor learning as an information encoding procedure, that is, a procedure of encoding a motor skill into primitives. The capacity of encoding is determined by the number of recruited primitives, which depends on how many primitives are "visited" by the movement, and this leads to a rather counterintuitive prediction that faster movement, where a larger number of motor primitives are involved, allows learning more complicated motor skills. Here, we provide a set of experimental results that support this hypothesis. First, we show that learning occurs only with movement, that is, only with nonzero encoding capacity. When participants were asked to counteract a rotating force applied to a robotic handle, they were unable to do so when maintaining a static posture but were able to adapt when making small circular movements. Our second experiment further investigated how adaptation is affected by movement speed. When adapting to a simple (low-information-content) force field, fast (high-capacity) movement did not have an advantage over slow (low-capacity) movement. However, for a complex (high-information-content) force field, the fast movement showed a significant advantage over slow movement. Our final experiment confirmed that the observed benefit of high-speed movement is only weakly affected by mechanical factors. Taken together, our results suggest that the encoding capacity is a genuine limiting factor of human motor adaptation.NEW & NOTEWORTHY We propose a novel concept called "encoding capacity" of motor adaptation, which describes an inherent limiting-factor of our brain's ability to learn new motor skills, just like any other storage system. By reinterpreting the existing primitive-based models of motor learning, we hypothesize that the encoding capacity is determined by the size of the movement, and present a set of experimental evidence suggesting that such limiting effect of encoding capacity does exist in human motor adaptation.
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Adaptação Fisiológica/fisiologia , Destreza Motora/fisiologia , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Eletromiografia/métodos , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Dental age estimation of living individuals is difficult and challenging, and there is no consensus method in adults with permanent dentition. Thus, we aimed to provide an accurate and robust artificial intelligence (AI)-based diagnostic system for age-group estimation by incorporating a convolutional neural network (CNN) using dental X-ray image patches of the first molars extracted via panoramic radiography. The data set consisted of four first molar images from the right and left sides of the maxilla and mandible of each of 1586 individuals across all age groups, which were extracted from their panoramic radiographs. The accuracy of the tooth-wise estimation was 89.05 to 90.27%. Performance accuracy was evaluated mainly using a majority voting system and area under curve (AUC) scores. The AUC scores ranged from 0.94 to 0.98 for all age groups, which indicates outstanding capacity. The learned features of CNNs were visualized as a heatmap, and revealed that CNNs focus on differentiated anatomical parameters, including tooth pulp, alveolar bone level, or interdental space, depending on the age and location of the tooth. With this, we provided a deeper understanding of the most informative regions distinguished by age groups. The prediction accuracy and heat map analyses support that this AI-based age-group determination model is plausible and useful.
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Determinação da Idade pelos Dentes/métodos , Inteligência Artificial , Dente Molar/diagnóstico por imagem , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Dente Molar/anatomia & histologia , Redes Neurais de Computação , Radiografia Dentária , Radiografia Panorâmica , Reprodutibilidade dos Testes , Adulto JovemRESUMO
INTRODUCTION: A psychometric analysis on type 2 diabetic (T2D) patients was performed to assess whether glycated hemoglobin (HbA1c) levels were dependent upon either the psychologic or economic attitude toward the use of insulin as a treatment for their diabetic condition. METHODS: A cross-sectional study was designed using 271 patients with T2D who regularly visited a tertiary referral hospital in South Korea from June 2019 to December 2019. Each patient enrolled in this protocol was treated with insulin for at least 6 months, had recordings of their plasma HbA1c measurement, and completed validated questionnaires consisting of items focusing on patient attitudes toward insulin use [Insulin Treatment Appraisal Scale (ITAS)] and cost-related issues related to diabetic supply purchase. Multiple regression analyses were performed to determine the association between their HbA1c and each item on the questionnaires. RESULTS: In both males and females, there was a significant association (P < 0.05) between HbA1c levels and multiple items on the ITAS questionnaire, which are generally regarded as a negative perception (ITAS 1 "personal failure" and ITAS 2 "illness severity" in males and ITAS 12 "expected harm" and ITAS 15 "restrictiveness" in females). In females, however, not all perceptions were negative, since one item (ITAS 8 "anticipated effect") was correlated with the measurement of a lower HbA1c level (- 0.495 ± 0.211, P < 0.05). There was no association between the levels of HbA1c and the cost of insulin or associated diabetic supplies. Since only a few patients in this study chose to reduce their drug dosing because of cost, the resistance to using insulin is likely not driven by economic reasons. CONCLUSION: The psychometric results of the ITAS suggested that HbA1c levels were directly associated with a positive attitude of the patient to willingly use insulin for therapy. The cost of the insulin therapy was not associated with HbA1c levels. These findings in the Korean population suggest that continued education is needed to ensure that T2D patients have a reinforced positive psychology toward the use of insulin in the control of their glycemia.
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A resurgence in the development of newer gene therapy systems has led to recent successes in the treatment of B cell cancers, retinal degeneration and neuromuscular atrophy. Gene therapy offers the ability to treat the patient at the root cause of their malady by restoring normal gene function and arresting the pathological progression of their genetic disease. The current standard of care for most genetic diseases is based upon the symptomatic treatment with polypharmacy while minimizing any potential adverse effects attributed to the off-target and drug-drug interactions on the target or other organs. In the kidney, however, the development of gene therapy modifications to specific renal cells has lagged far behind those in other organ systems. Some positive strides in the past few years provide continued enthusiasm to invest the time and effort in the development of new gene therapy vectors for medical intervention to treat kidney diseases. This mini-review will systematically describe the pros and cons of the most commonly tested gene therapy vector systems derived from adenovirus, retrovirus, and adeno-associated virus and provide insight about their potential utility as a therapy for various types of genetic diseases in the kidney.
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Terapia Genética/métodos , Nefropatias/terapia , Adenoviridae/genética , Animais , Proteínas do Capsídeo/genética , Dependovirus/genética , Vetores Genéticos/administração & dosagem , Humanos , Lentivirus/genética , Camundongos , Transdução Genética/métodosRESUMO
This paper proposes a Gaussian process-based method for trajectory learning and generation of individualized gait motions at arbitrary user-designated walking speeds, intended to be used in generating reference motions for robotic gait rehabilitation systems. We utilize a nonlinear dimension reduction technique based on Gaussian process dynamical models (GPDMs), in which the internal dynamics is modeled as a second-order Markov process evolving in a lower-dimensional latent space. After the GPDM parameters are identified with training data obtained from gait motions of healthy subjects walking at different speeds, our method then employs Gaussian process regression (GPR) to predict the initial two states of the latent space dynamics from any arbitrary desired walking speed and the anthropometric parameters of the test subject. Motions are then generated by directly mapping the latent space dynamics to joint trajectories. Experimental studies involving more than 100 subjects indicate that our method generates gait patterns with 30% less mean square prediction errors compared to recent state-of-the-art methods, while also allowing for arbitrary user-specified walking speeds.
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Transtornos Neurológicos da Marcha/fisiopatologia , Transtornos Neurológicos da Marcha/reabilitação , Marcha , Distribuição Normal , Robótica/métodos , Adulto , Idoso , Algoritmos , Antropometria , Fenômenos Biomecânicos , Feminino , Voluntários Saudáveis , Humanos , Articulações/fisiopatologia , Perna (Membro)/fisiopatologia , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Modelos Estatísticos , Velocidade de Caminhada , Adulto JovemRESUMO
Ischemic injury is a primary contributor to the initiation of renal tubular epithelial cell damage in sickle cell disease (SCD). In this study, we investigated the effects of bilateral ischemia-reperfusion injury, which is a common type of acute kidney injury (AKI), in male and female genetic mouse model of SCD. Bilateral occlusion of both renal hila for 21â¯min led to a significantly higher detection of established serum markers of AKI (creatinine, KIM-1 and NGAL) compared to sham-operated male SCD mice. Severe damage to the outer medullary tubules was determined in the ischemia-reperfision injury (IRI)-treated SCD male mice. In female SCD mice with a longer ischemic time (23â¯min), the serum markers of AKI were not as highly elevated compared to their male counterparts, and the extent of outer medullary tubular injury was less severe. To assess the potential benefit in the use of hydroxyurea (50â¯mg/kg IP) following bilateral renal IRI, we observed that the serum markers of AKI and the outer medullary tubular damage were markedly improved compared to male SCD mice that were not treated with hydroxyurea. In this study, we confirmed that male SCD mice were more susceptible to increased tubular damage and a loss in renal function compared to female SCD mice, and that hydroxyurea may partially prevent the extent of tubular injury following severe ischemia-reperfusion injury in SCD.
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Injúria Renal Aguda/fisiopatologia , Anemia Falciforme/tratamento farmacológico , Hidroxiureia/farmacologia , Túbulos Renais/efeitos dos fármacos , Traumatismo por Reperfusão/fisiopatologia , Injúria Renal Aguda/sangue , Anemia Falciforme/sangue , Animais , Antidrepanocíticos/farmacologia , Biomarcadores/sangue , Creatinina/sangue , Modelos Animais de Doenças , Feminino , Receptor Celular 1 do Vírus da Hepatite A/sangue , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Lipocalina-2/sangue , Masculino , Camundongos , Traumatismo por Reperfusão/sangueRESUMO
Pleuromutilin is a promising pharmacophore to design new antibacterial agents for Gram-positive bacteria. However, there are limited studies on the development of pleuromutilin analogues that inhibit growth of Mycobacterium tuberculosis (Mtb). In screening of our library of pleuromutilin derivatives, UT-800 (1) was identified to kill replicating- and non-replicating Mtb with the MIC values of 0.83 and 1.20⯵g/mL, respectively. UT-800 also kills intracellular Mtb faster than rifampicin at 2× MIC concentrations. Pharmacokinetic studies indicate that 1 has an oral bioavailability with an average F-value of 27.6%. Pleuromutilin may have the potential to be developed into an orally administered anti-TB drug.