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1.
Br J Dermatol ; 183(1): 146-154, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31605618

RESUMO

BACKGROUND: Skin tears are acute wounds that are frequently misdiagnosed and under-reported. A standardized and globally adopted skin tear classification system with supporting evidence for diagnostic validity and reliability is required to allow assessment and reporting in a consistent way. OBJECTIVES: To measure the validity and reliability of the International Skin Tear Advisory Panel (ISTAP) Classification System internationally. METHODS: A multicountry study was set up to validate the content of the ISTAP Classification System through expert consultation in a two-round Delphi procedure involving 17 experts from 11 countries. An online survey including 24 skin tear photographs was conducted in a convenience sample of 1601 healthcare professionals from 44 countries to measure diagnostic accuracy, agreement, inter-rater reliability and intrarater reliability of the instrument. RESULTS: A definition for the concept of a 'skin flap' in the area of skin tears was developed and added to the initial ISTAP Classification System consisting of three skin tear types. The overall agreement with the reference standard was 0·79 [95% confidence interval (CI) 0·79-0·80] and sensitivity ranged from 0·74 (95% CI 0·73-0·75) to 0·88 (95% CI 0·87-0·88). The inter-rater reliability was 0·57 (95% CI 0·57-0·57). The Cohen's Kappa measuring intrarater reliability was 0·74 (95% CI 0·73-0·75). CONCLUSIONS: The ISTAP Classification System is supported by evidence for validity and reliability. The ISTAP Classification System should be used for systematic assessment and reporting of skin tears in clinical practice and research globally. What's already known about this topic? Skin tears are common acute wounds that are misdiagnosed and under-reported too often. A skin tear classification system is needed to standardize documentation and description for clinical practice, audit and research. What does this study add? The International Skin Tear Advisory Panel Classification System was psychometrically tested in 1601 healthcare professionals from 44 countries. Diagnostic accuracy was high when differentiating between type 1, 2 and 3 skin tears using a set of validated photographs.


Assuntos
Lacerações , Lesões dos Tecidos Moles , Humanos , Lacerações/diagnóstico , Reprodutibilidade dos Testes , Pele/lesões , Inquéritos e Questionários
2.
Int J Biol Macromol ; 257(Pt 1): 128448, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042323

RESUMO

The current research was planned to enhance the bioavailability of hydrophobic drug after oral administration through the development of a nanoparticle drug delivery system (DDS). Therefore, febuxostat-loaded chitosan nanoparticles (FLC NPs) were prepared using a modified ionic gelation method and optimized the reaction conditions through the design of experiments. Design expert software was used to check the desirability of the central composite design and the interactive effects of the independent variables (chitosan concentration, ratio of chitosan to linker, and pH of the medium) on the response variables (size distribution, zeta potential, polydispersity index (PDI), and entrapment efficiency (EE)) of FLC NPs. All ingredients of the optimized formulation (formulation Q) were compatible with each other as evident from FTIR, PXRD, and TGA studies, and displayed 234.7 nm particle size, 0.158 PDI, 25.8 mV zeta potential, and 76.9 % EE. TEM, SEM, and AFM exhibited a smooth, dense, and uniform structure without any visible pores in the structure of FLC NPs. The in vitro and in vivo drug release studies described a sustained release pattern of febuxostat and increased relative bioavailability by 286.63 %. Considering these findings, this chitosan nanoparticle DDS can further be used for improving the EE and bioavailability of hydrophobic drugs.


Assuntos
Quitosana , Nanopartículas , Quitosana/química , Portadores de Fármacos/química , Febuxostat/farmacologia , Liberação Controlada de Fármacos , Disponibilidade Biológica , Nanopartículas/química , Tamanho da Partícula
3.
PLoS One ; 19(5): e0302657, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38787908

RESUMO

Ethnopharmacological relevance of Saussurea species for anti-cancer compounds instigated us to develop chemotherapeutic herbal tablets. This study was an ongoing part of our previous research based on the scientific evaluation of Saussurea heteromalla (S. heteromalla) for anti-cancer lead compounds. In the current study, S. heteromalla herbal tablets (500 /800 mg) were designed and evaluated for anti-cancer activity. Arctigenin was found as a bioactive lead molecule with anti-cancer potential for cervical cancer. The in vitro results on the HeLa cell line supported the ethnopharmacological relevance and traditional utilization of S. heteromalla and provided the scientific basis for the management of cervical cancer as proclaimed by traditional practitioners in China. LD50 of the crude extract was established trough oral acute toxicity profiling in mice, wherein the minimum lethal dose was noticed as higher than 1000 mg/kg body weight orally. Chromatographic fingerprint analysis ensured the identity and consistency of S. heteromalla in herbal tablets in terms of standardization of the herbal drug. About 99.15% of the drug (S. heteromalla crude extract) was recovered in herbal tablets (RSD: 0.45%). In vitro drug release profile was found to be more than 87% within 1 h, which was also correlated with different mathematical kinetic models of drug release (r2 = 0.992), indicating that drug release from matrix tablets into the blood is constant throughout the delivery. The dosage form was found stable after an accelerated stability parameters study which may be used for anti-cervical cancer therapy in the future, if it qualifies successful preclinical investigation parameters.


Assuntos
Extratos Vegetais , Saussurea , Saussurea/química , Animais , Humanos , Camundongos , Células HeLa , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Extratos Vegetais/farmacologia , Lignanas/farmacologia , Lignanas/química , Feminino , Furanos/toxicidade , Furanos/química , Furanos/farmacologia , Comprimidos , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Masculino , Antineoplásicos/farmacologia , Antineoplásicos/química , Dose Letal Mediana , Testes de Toxicidade Aguda , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/toxicidade , Medicamentos de Ervas Chinesas/farmacologia
4.
Int J Biol Macromol ; 270(Pt 1): 132306, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38740152

RESUMO

Combining natural polysaccharides with synthetic materials improves their functional properties which are essential for designing sustained-release drug delivery systems. In this context, the Aloe vera leaf mucilage/hydrogel (ALH) was reacted with acrylic acid (AA) to synthesize a copolymerized hydrogel, i.e., ALH-grafted-Polyacrylic acid (ALH-g-PAA) through free radical copolymerization. Concentrations of the crosslinker N,N'-methylene-bis-acrylamide (MBA), and the initiator potassium persulfate (KPS) were optimized to study their effects on ALH-g-PAA swelling. The FTIR and solid-state NMR (CP/MAS 13C NMR) spectra witnessed the formation of ALH-g-PAA. Scanning electron microscopy (SEM) analysis revealed superporous nature of ALH-g-PAA. The gel fraction (%) of ALH-g-PAA was directly related to the concentrations of AA and MBA whereas the sol fraction was inversely related to the concentrations of AA and MBA. The porosity (%) of ALH-g-PAA directly depends on the concentration of AA and MBA. The ALH-g-PAA swelled admirably at pH 7.4 and insignificantly at pH 1.2. The ALH-g-PAA offered on/off switching properties at pH 7.4/1.2. The metoprolol tartrate was loaded on different formulations of ALH-g-PAA. The ALH-g-PAA showed pH, time, and swelling-dependent release of metoprolol tartrate (MT) for 24 h following the first-order kinetic and Korsmeyer-Peppas model. Haemocompatibility studies ascertained the non-thrombogenic and non-hemolytic behavior of ALH-g-PAA.


Assuntos
Aloe , Hidrogéis , Mananas , Aloe/química , Concentração de Íons de Hidrogênio , Mananas/química , Hidrogéis/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Polímeros/química , Porosidade , Resinas Acrílicas/química , Acrilatos
5.
J Biotechnol ; 374: 17-30, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37482251

RESUMO

As the world grapples with an imminent energy crisis brought on by the depletion of nonrenewable resources, such as petroleum, the necessity for alternative and eco-friendly power sources becomes increasingly apparent. In this regard harnessing knowledge gained from natural microorganisms to produce electricity using economical substrates is a promising solution through microbial fuel cells (MFCs). Microbial fuel cells leverage microbes' catabolic abilities to break down organic matter and release electrons that are subsequently transported across an external circuit for electricity generation. This article delves into the fundamental components involved in MFC construction and explores crucial factors that impact their performance including substrate oxidation, electron transfer, and internal resistance. Additionally, it offers a comprehensive analysis of existing microbial fuel cell designs while highlighting their respective strengths and weaknesses. Finally, the article showcases cost-effective MFC models based on thorough studies conducted worldwide while illuminating potential practical applications of this renewable energy technology.


Assuntos
Fontes de Energia Bioelétrica , Águas Residuárias , Eletricidade , Oxirredução , Eletrodos
6.
RSC Adv ; 13(40): 28139-28147, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37753394

RESUMO

Applying a multistep approach, novel indolin-2-ones (IND) that possess an arylidene motif have been synthesized. Eight compounds were chosen for different biological tests (antimicrobial and cytotoxicity). IND containing 2-thienyl (4h) fragment have been found to exhibit good antimicrobial activity against B. cereus. Molecules that have 3-aminophenyl (4d) or 2-pyridyl (4g) groups have shown the best antifungal activities against all tested fungi. These compounds have also been noticed as promising pharmaceuticals against MCF-7 cancer cell lines. Experimental outcomes from the investigation of the interaction of 4d with DNA implied its moderate binding to DNA (KSV = 1.35 × 104 and 3.05 × 104 M-1 for EB and Hoechst binder, respectively). However, considerably stronger binding of 4d to BSA has been evidenced (Ka = 6.1 × 106 M-1). In summary, IND that contains m-aminobenzylidene fragment (4d) exhibits a good dual biological activity making it a promising candidate for further investigation in the drug discovery sector.

7.
Gels ; 9(7)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37504404

RESUMO

The current research work focuses on the extraction and optimization of the hydrogel (AVM) from the seeds of Artemisia vulgaris using Box-Behnken design-response surface methodology (BBD-RSM). The AVM was obtained through a hot water extraction process. The influence of different factors, including pH (U = 4 to 10), temperature (V = 25 to 110 °C), seed/water ratio, i.e., S/W ratio (W = 1/10 to 1/70 w/v), and seed/water contact time, i.e., S/W time (X = 1 to 12 h) on the yield of AVM was evaluated. The p-value for the analysis of variance (ANOVA) was found to be <0.001, indicating that the yield of AVM mainly depended on the abovementioned factors. The highest yield of AVM, i.e., 15.86%, was found at a pH of 7.12, temperature of 80.04 °C, S/W ratio of 1/33.24 w/v, and S/W time of 8.73 h according to Design-Expert Software. The study of the pH-responsive behavior of AVM in tablet form (formulation AVT3) revealed that AVM is a pH-responsive material with significantly high swelling at pH 7.4. However, less swelling was witnessed at pH 1.2. Moreover, AVM was found to be a sustained release material for esomeprazole at pH 7.4 for 12 h. The drug release from AVT3 was according to the super case-II transport mechanism and zero-order kinetics.

8.
Cardiovasc Ther ; 2023: 8166840, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37214130

RESUMO

The current study was designed to determine pulegone's antihypertensive and vasoprotective activity in L-NAME-induced hypertensive rats. Firstly, the hypotensive dose-response relationship of pulegone was evaluated in normotensive anesthetized rats using the invasive method. Secondly, the mechanism involved in hypotensive activity was determined in the presence of pharmacological drugs such as atropine/muscarinic receptor blocker (1 mg/kg), L-NAME/NOS inhibitor (20 mg/kg), and indomethacin/COX inhibitor (5 mg/kg) in anesthetized rats. Furthermore, studies were carried out to assess the preventive effect of pulegone in L-NAME-induced hypertensive rats. Hypertension was induced in rats by administering L-NAME (40 mg/kg) orally for 28 days. Rats were divided into six groups which were treated orally with tween 80 (placebo), captopril (10 mg/kg), and different doses of pulegone (20 mg/kg, 40 mg/kg, and 80 mg/kg). Blood pressure, urine volume, sodium, and body weight were monitored weekly. After 28 days, the effect of pulegone on lipid profile, hepatic markers, antioxidant enzymes, and nitric oxide was estimated from the serum of treated rats. Moreover, plasma mRNA expression of eNOS, ACE, ICAM1, and EDN1 was measured using real-time PCR. Results show that pulegone dose-dependently decreased blood pressure and heart rate in normotensive rats, with the highest effect at 30 mg/kg/i.v. The hypotensive effect of pulegone was reduced in the presence of atropine and indomethacin, whereas L-NAME did not change its hypotensive effect. Concurrent treatment with pulegone for four weeks in L-NAME-treated rats caused a reduction in both systolic blood pressure and heart rate, reversed the reduced levels of serum nitric oxide (NO), and ameliorated lipid profile and oxidative stress markers. Treatment with pulegone also improved the vascular response to acetylcholine. Plasma mRNA expression of eNOS was reduced, whereas ACE, ICAM1, and EDN1 levels were high in the L-NAME group, which was facilitated by pulegone treatment. To conclude, pulegone prevented L-NAME-induced hypertension by demonstrating a hypotensive effect through muscarinic receptors and cyclooxygenase pathway, indicating its use as a potential candidate in managing hypertension.


Assuntos
Hipertensão , Prostaglandina-Endoperóxido Sintases , Ratos , Animais , NG-Nitroarginina Metil Éster/efeitos adversos , Prostaglandina-Endoperóxido Sintases/efeitos adversos , Óxido Nítrico/metabolismo , Hipertensão/induzido quimicamente , Hipertensão/prevenção & controle , Hipertensão/tratamento farmacológico , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Indometacina/efeitos adversos , Receptores Muscarínicos/uso terapêutico , RNA Mensageiro , Derivados da Atropina/efeitos adversos , Lipídeos
9.
Front Pharmacol ; 14: 1258387, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37808196

RESUMO

Background: We investigated the anti-cancer effect of carnosine-loaded niosomes (Car-NIO) and melittin-loaded niosomes (Mel-NIO) with olaparib in breast cancer cell lines (MCF-7 and MDA-MB-231). Methods: The thin film method was used for preparing the niosomes and characterized in terms of morphology, size, and polydispersity index (PDI). We further evaluated the impact of these peptides on breast cancer cells viability, RT-qPCR assays, malondialdehyde (MDA) activity, and cell cycle progression, to determine if these are linked to carnosine and melittin's anti-proliferative properties. Results: Car-NIO and Mel-NIO in vitro study inhibited cancer cell viability. They have also upregulated the expression of protein 53 (P53), BCL2-Associated X Protein (Bax), caspase-9, caspase-3, programmed cell death 4 (PDCD4), and Forkhead box O3 (FOXO3), while downregulated the expression of B-cell lymphoma 2 (Bcl2), poly (ADP-ribose) polymerase (PARP 1), and MicroRNA-183 (miRNA-183). The MCF-7 cells were arrested at the G2/M phase in Car-NIO, on the other hand, the MDA-MB-231 cells were arrested at the S phase. While the Mel-NIO and olaparib arrested the MCF-7 and MDA-MB-231 cells at the G0/1 phase. Conclusion: Our study successfully declared that Mel-NIO had more anti-cancer effects than Car-NIO in both MCF-7 and MDA-MB-231 breast cancer cells.

10.
Biomedicines ; 11(9)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37760913

RESUMO

Myocardial infarction (MI) is the principal cause of premature death. Protecting myocardium from ischemia is the main focus of intense research. 7-hydroxy frullanolide (7-HF) is a potent anti-inflammatory agent, showing its efficacy in different acute and chronic inflammatory disorders such as atherosclerosis, suggesting it can be a potential cardioprotective agent. For the induction of MI, Sprague-Dawley rats (n = 5) were administered isoproterenol (ISO) 85 mg/kg s.c at 24 h intervals for two days. The potential cardioprotective effect of 7-HF and its mechanisms were explored by in vivo and in vitro methods. 7-HF significantly prevented the extent of myocardial injury by decreasing the infarct size, preserving the histology of myocardial tissue, and reducing the release of cardiac biomarkers. Further, 7-HF increased the mRNA expression of cardioprotective gene Nrf2 and reduced the mRNA expression of iNOS. 7-HF also improved cardiac function by decreasing the cardiac workload through its negative chronotropic and negative ionotropic effect, as well as by reducing peripheral vascular resistance due to the inhibition of voltage-dependent calcium channels and the release of calcium from intracellular calcium stores. In conclusion, 7-HF showed cardioprotective effects in the MI model, which might be due to modulating the expression of iNOS and Nrf2 genes as well as improving cardiac functions.

11.
Expert Opin Ther Targets ; 27(12): 1257-1269, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38112471

RESUMO

INTRODUCTION: In medicinal chemistry, privileged structures have been frequently exploited as a successful template for drug discovery. Common simple scaffolds like chalcone are present in a wide range of naturally occurring chemicals. Chalcone exhibits extensive biological activity and has drawn attention in this context due to its function in the GABA receptor. Epilepsy and GABA receptors are related. It is a chronic neurological condition that affects globally. AREAS COVERED: Numerous neurological disorders, including anxiety and epilepsy, have been related to GABA, the brain's most prevalent inhibitory neurotransmitter. We go through the role of GABA receptors in anxiety and epilepsy in this review. The structure-activity relationship of chalcone and its derivatives on the GABA receptor is covered in our final section. EXPERT OPINION: GABA is a potential therapeutic target for issues associated with the nervous system. We talk about the potential effects of chalcone as a treatment for epilepsy and anxiety on the GABA receptor. Therefore, thorough research is necessary in this regard; the value of in silico tools in developing and enhancing GABA agonists is significant.


Assuntos
Chalcona , Chalconas , Epilepsia , Humanos , Receptores de GABA , Chalcona/química , Chalcona/farmacologia , Epilepsia/tratamento farmacológico , Ácido gama-Aminobutírico , Receptores de GABA-A/fisiologia
12.
ACS Omega ; 8(40): 37128-37139, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37841186

RESUMO

Geraniol (GER) is a plant-derived acyclic isoprenoid monoterpene that has displayed anti-inflammatory effects in numerous in vivo and in vitro models. This study was therefore designed to evaluate the antiarthritic potential of GER in complete Freund's adjuvant (CFA)-induced inflammatory arthritis (IA) model in rats. IA was induced by intraplantar injection of CFA (0.1 mL), and a week after CFA administration, rats were treated with various doses of methotrexate (MTX; 1 mg/kg) or GER (25, 50, and 100 mg/kg). Treatments were given on every alternate day, and animals were sacrificed on the 35th day. Paw volume, histopathological, hematological, radiographic, and qPCR analyses were performed to analyze the severity of the disease. GER significantly reduced paw edema after 35 days of treatment, and these results were comparable to the MTX-treated group. GER-treated animals displayed a perfect joint structure with minimal inflammation and no signs of cartilage or bone damage. Moreover, GER restored red blood cell and hemoglobin levels, normalized erythrocyte sedimentation rate, platelet, and c-reactive protein values, and also attenuated the levels of rheumatoid factor. RT-qPCR analysis demonstrated that GER decreased mRNA expression of pro-inflammatory cytokines like tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta. GER also down-regulated the transcript levels of cyclooxygenase-2 (COX-2), microsomal prostaglandin E synthase-1, prostaglandin D2 synthase, and interstitial collagenase (MMP-1). Molecular docking of GER with COX-2, TNF-α, and MMP-1 also revealed that the antiarthritic effects of GER could be due to its direct interactions with these mediators. Based on our findings, it is conceivable that the antiarthritic effects of GER could be attributed to downregulation of pro-inflammatory mediators and protease like MMP-1.

13.
J Biomol Struct Dyn ; : 1-14, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38153371

RESUMO

NSAIDs represent a mainstay in pain and inflammation suppression, and their actions are mainly based on inhibiting COX-1 and COX-2 enzymes.Due to the adverse effects of these drugs, especially on the stomach and heart, scientists efforts have been directed to manufacture selective COX-2 without cardiovascular side effects and with minimal effects on the stomach. The cardiovascular side effects are thought to be related to the chemical composition rather than mechanism of action of these drugs.Novel pyridopyrimidines, 9a-j, were prepared and their chemical structures were confirmed by NMR, mass and IR Spectra, and elemental analysis. The effect of the 9a-j compounds on COX-1 and COX-2 was assessed and it was found that 2-hydrazino-5-(4-methoxyphenyl)-7-phenyl-3H-pyrido[2,3-d)pyrimidin-4-one (9d) was the most potent COX-2 inhibitor (IC50 = 0.54 uM) compared to celecoxib (IC50 = 1.11 uM) with selectivity indices of 6.56 and 5.12, respectively.The in vivo inhibition of paw edema of novel compounds 9a-j was measured using carrageenan-induced paw edema method, and that 2-hydrazino-5-(4-methoxyphenyl)-7-phenyl-3H-pyrido[2,3-d)pyrimidin-4-one (9d) showed the best inhibitory activity in comparison with the other compounds and celecoxib.The gastroprotective effect of the potent derivatives 9d, 9e, 9f, 9 g and 9h was investigated. 2-Hydrazino-5-(4-methoxyphenyl)-7-phenyl-3H-pyrido[2,3-d)pyrimidin-4-one (9d) and 7-(chlorophenyl)-hydrazino-5-(4-methoxyphenyl)-3H-pyrido[2,3-d)pyrimidin-4-one (9e) showed ulcer indices comparable to celecoxib (1 and 0.5 vs 0.5, respectively). Docking studies were carried out and they confirmed the mechanistic action of the designed compoundsCommunicated by Ramaswamy H. Sarma.

14.
Hepatology ; 49(5): 1655-63, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19309719

RESUMO

UNLABELLED: We have used immunohistochemical and histochemical techniques to identify patches of hepatocytes deficient in the enzyme cytochrome c oxidase, a component of the electron transport chain and encoded by mitochondrial DNA (mtDNA). These patches invariably abutted the portal tracts and expanded laterally as they spread toward the hepatic veins. Here we investigate, using mtDNA mutations as a marker of clonal expansion, the clonality of these patches. Negative hepatocytes were laser-capture microdissected and mutations identified by polymerase chain reaction sequencing of the entire mtDNA genome. Patches of cytochrome c oxidase-deficient hepatocytes were clonal, suggesting an origin from a long-lived cell, presumably a stem cell. Immunohistochemical analysis of function and proliferation suggested that these mutations in cytochrome c oxidase-deficient hepatocytes were nonpathogenic. CONCLUSION: These data show, for the first time, that clonal proliferative units exist in the human liver, an origin from a periportal niche is most likely, and that the trajectory of the units is compatible with a migration of cells from the periportal regions to the hepatic veins.


Assuntos
Linhagem da Célula , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Hepatócitos/enzimologia , Fígado/citologia , Nicho de Células-Tronco/citologia , Análise Mutacional de DNA , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Humanos , Imuno-Histoquímica
15.
Stem Cells ; 27(6): 1410-20, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19489031

RESUMO

Methods for lineage tracing of stem cell progeny in human tissues are currently not available. We describe a technique for detecting the expansion of a single cell's progeny that contain clonal mitochondrial DNA (mtDNA) mutations affecting the expression of mtDNA-encoded cytochrome c oxidase (COX). Because such mutations take up to 40 years to become phenotypically apparent, we believe these clonal patches originate in stem cells. Dual-color enzyme histochemistry was used to identify COX-deficient cells, and mutations were confirmed by microdissection of single cells with polymerase chain reaction sequencing of the entire mtDNA genome. These techniques have been applied to human intestine, liver, pancreas, and skin. Our results suggest that the stem cell niche is located at the base of colonic crypts and above the Paneth cell region in the small intestine, in accord with dynamic cell kinetic studies in animals. In the pancreas, exocrine tissue progenitors appeared to be located in or close to interlobular ducts, and, in the liver, we propose that stem cells are located in the periportal region. In the skin, the origin of a basal cell carcinoma appeared to be from the outer root sheath of the hair follicle. We propose that this is a general method for detecting clonal cell populations from which the location of the niche can be inferred, also affording the generation of cell fate maps, all in human tissues. In addition, the technique allows analysis of the origin of human tumors from specific tissue sites.


Assuntos
Linhagem da Célula , DNA Mitocondrial/genética , Células Epiteliais/citologia , Células Clonais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Humanos , Imuno-Histoquímica , Mutação , Nicho de Células-Tronco/citologia
16.
NPJ Regen Med ; 5: 3, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32133156

RESUMO

Therapeutic approaches requiring the intravenous injection of autologous or allogeneic mesenchymal stromal cells (MSCs) are currently being evaluated for treatment of a range of diseases, including orthopaedic injuries. An alternative approach would be to mobilise endogenous MSCs into the blood, thereby reducing costs and obviating regulatory and technical hurdles associated with development of cell therapies. However, pharmacological tools for MSC mobilisation are currently lacking. Here we show that ß3 adrenergic agonists (ß3AR) in combination with a CXCR4 antagonist, AMD3100/Plerixafor, can mobilise MSCs into the blood in mice and rats. Mechanistically we show that reversal of the CXCL12 gradient across the bone marrow endothelium and local generation of endocannabinoids may both play a role in this process. Using a spine fusion model we provide evidence that this pharmacological strategy for MSC mobilisation enhances bone formation.

17.
Stem Cells ; 26(1): 108-18, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17901405

RESUMO

Complex biomolecules absorb in the mid-infrared (lambda = 2-20 microm), giving vibrational spectra associated with structure and function. We used Fourier transform infrared (FTIR) microspectroscopy to "fingerprint" locations along the length of human small and large intestinal crypts. Paraffin-embedded slices of normal human gut were sectioned (10 microm thick) and mounted to facilitate infrared (IR) spectral analyses. IR spectra were collected using globar (15 microm x 15 microm aperture) FTIR microspectroscopy in reflection mode, synchrotron (

Assuntos
Biomarcadores/análise , Mucosa Intestinal/citologia , Espectroscopia de Infravermelho com Transformada de Fourier , Células-Tronco/citologia , Humanos , Imuno-Histoquímica , Análise de Componente Principal
18.
Int J Health Sci (Qassim) ; 10(2): 249-57, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27103907

RESUMO

OBJECTIVES: To assess the role, efficacy and tolerability of levodopa-carbidopa in the management of small and older children with different types of amblyopia. METHODOLOGY: Prospective randomised placebo controlled clinical study, in which 50 amblyopic patients between 5 and 20 years of age with visual acuity (V/A) < 20/40 were included, was carried on. After having attained the best possible refractive correction, patients were randomly divided into 2 groups. They were prescribed levodopa-carbidopa (10:1) (4-6mg/kg/day in 2-3 divided doses) or placebo, plus full-time occlusion of the sound eye, for a period of three months. Assessment of improvement in V/A, compliance and tolerance was done at follow up visits. Data was analyzed using computer software Ms-Excel and Epi-Info Version 6.0. The statistical significance was assessed by Chi-Square/Fisher's Exact Test. RESULTS: Visual acuity for the amblyopic eye improved significantly in both groups but there was significant improvement in group 1 than group 2 (P = 0.0001). In a subgroup of patients older than 12 years, levodopa group showed statistically significant improvement in baseline V/A (P = 0.0001). In patients with severe amblyopia, each group showed significant improvement in baseline V/A (p < 0.05), but was significantly more in group 1 (P = 0.0001). Compliance rates were similar among the groups and levodopa-carbidopa at a dose range of 4-6 mg/kg/day was well tolerated. CONCLUSION: Levodopa-carbidopa can be used as an adjunct to conventional occlusion therapy in amblyopia particularly in older children and severe cases of amblyopia, and it is well tolerated.

19.
Pharmacol Ther ; 151: 107-20, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25827580

RESUMO

Regenerative medicine using mesenchymal stem cells for the purposes of tissue repair has garnered considerable public attention due to the potential of returning tissues and organs to a normal, healthy state after injury or damage has occurred. To achieve this, progenitor cells such as pericytes and bone marrow-derived mesenchymal stem cells can be delivered exogenously, mobilised and recruited from within the body or transplanted in the form organs and tissues grown in the laboratory from stem cells. In this review, we summarise the recent evidence supporting the use of endogenously mobilised stem cell populations to enhance tissue repair along with the use of mesenchymal stem cells and pericytes in the development of engineered tissues. Finally, we conclude with an overview of currently available therapeutic options to manipulate endogenous stem cells to promote tissue repair.


Assuntos
Células-Tronco Mesenquimais/fisiologia , Pericitos/fisiologia , Regeneração , Engenharia Tecidual , Animais , Movimento Celular , Fibrose/patologia , Fibrose/terapia , Humanos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Neovascularização Fisiológica , Pericitos/efeitos dos fármacos , Pericitos/transplante
20.
J Pediatr Surg ; 26(10): 1202-6, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1779330

RESUMO

In 10 years, 57 infants with Hirschsprung's disease underwent endorectal pull-through (ERPT). Postoperatively, 3 patients died. Of the 44 survivors with an intact endorectal anastomosis aged more than 3 years, 23 (52%) had an excellent result, and of the 28 children more than 5 years old, 23 (82%) had a satisfactory result. Of the 53 known survivors of all ages, 18% suffered from diarrhea with intermittent incontinence and 5 (9.4%) had undergone a Duhamel procedure within 4 years of ERPT.


Assuntos
Doença de Hirschsprung/cirurgia , Complicações Pós-Operatórias/epidemiologia , Anastomose Cirúrgica , Diarreia/epidemiologia , Incontinência Fecal/epidemiologia , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Reto/cirurgia , Recidiva , Reoperação , Fatores de Tempo , Resultado do Tratamento
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