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Antimicrobial activity of a natural compound and analogs against multi-drug-resistant Gram-positive pathogens. Microbiol Spectr 2024; 12:e0151522. [PMID: 38289721 PMCID: PMC10913730 DOI: 10.1128/spectrum.01515-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 11/06/2023] [Indexed: 02/01/2024] Open
Abstract
The increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) has sparked global concern due to the dwindling availability of effective antibiotics. To increase our treatment options, researchers have investigated naturally occurring antimicrobial compounds and have identified MC21-A (C58), which has potent antimicrobial activity against MRSA. Recently, we have devised total synthesis schemes for C58 and its chloro-analog, C59. Here, we report that both compounds eradicate 90% of the 39 MRSA isolates tested [MIC90 and minimum bactericidal concentration (MBC90)] at lower or comparable concentrations compared to several standard-of-care (SoC) antimicrobials including daptomycin, vancomycin, and linezolid. Furthermore, a stable, water-soluble sodium salt of C59, C59Na, demonstrates antimicrobial activity comparable to C59. C59, unlike vancomycin, kills stationary-phase MRSA in a dose-dependent manner and completely eradicates MRSA biofilms. In contrast to vancomycin, exposing MRSA to sub-MIC concentrations of C59 does not result in the emergence of spontaneous resistance. Similarly, in a multi-step study, C59 demonstrates a low propensity of resistance acquisition when compared to SoC antimicrobials, such as linezolid and clindamycin. Our findings suggest C58, C59, and C59Na are non-toxic to mammalian cells at concentrations that exert antimicrobial activity; the lethal dose at median cell viability (LD50) is at least fivefold higher than the MBC90 in the two mammalian cell lines tested. A morphological examination of the effects of C59 on a MRSA isolate suggests the inhibition of the cell division process as a mechanism of action. Our results demonstrate the potential of this naturally occurring compound and its analogs as non-toxic next-generation antimicrobials to combat MRSA infections. IMPORTANCE The rapid emergence of methicillin-resistant Staphylococcus aureus (MRSA) isolates has precipitated a critical need for novel antibiotics. We have developed a one-pot synthesis method for naturally occurring compounds such as MC21-A (C58) and its chloro-analog, C59. Our findings demonstrate that these compounds kill MRSA isolates at lower or comparable concentrations to standard-of-care (SoC) antimicrobials. C59 eradicates MRSA cells in biofilms, which are notoriously difficult to treat with SoC antibiotics. Additionally, the lack of resistance development observed with C59 treatment is a significant advantage when compared to currently available antibiotics. Furthermore, these compounds are non-toxic to mammalian cell lines at effective concentrations. Our findings indicate the potential of these compounds to treat MRSA infections and underscore the importance of exploring natural products for novel antibiotics. Further investigation will be essential to fully realize the therapeutic potential of these next-generation antimicrobials to address the critical issue of antimicrobial resistance.
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Synergistic Antimicrobial Effects of Ibuprofen Combined with Standard-of-Care Antibiotics against Cystic Fibrosis Pathogens. Biomedicines 2023; 11:2936. [PMID: 38001937 PMCID: PMC10669699 DOI: 10.3390/biomedicines11112936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/20/2023] [Accepted: 10/24/2023] [Indexed: 11/26/2023] Open
Abstract
Cystic fibrosis (CF) is a common life-shortening genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Lungs of CF patients are often colonized or infected with microorganisms requiring frequent courses of antibiotics. Antibiotic-resistant bacterial infections have been a growing concern in CF patients. Chronic bacterial infections and concomitant airway inflammation damage the lungs, ultimately leading to respiratory failure. Several clinical trials have demonstrated that high-dose ibuprofen reduces the rate of pulmonary function decline in CF patients. This beneficial effect has been attributed to the anti-inflammatory properties of ibuprofen. Previously, we have confirmed that high-dose ibuprofen demonstrates antimicrobial activity against P. aeruginosa both in vitro and in vivo. However, no study has examined the antimicrobial effect of combining ibuprofen with standard-of-care antimicrobials. Here, we evaluated the possible synergistic activity of combinations of common nonsteroidal anti-inflammatory drugs (NSAIDs), namely, ibuprofen, naproxen, and aspirin, with commonly used antibiotics for CF patients. The drug combinations were screened against different CF clinical isolates. Antibiotics that demonstrated increased efficacy in the presence of ibuprofen were further tested for potential synergistic effects between these NSAIDS and antimicrobials. Finally, a survival analysis of a P. aeruginosa murine infection model was used to demonstrate the efficacy of the most potent combination identified in in vitro screening. Our results suggest that combinations of ibuprofen with commonly used antibiotics demonstrate synergistic antimicrobial activity against drug-resistant, clinical bacterial strains in vitro. The efficacy of the combination of ceftazidime and ibuprofen against resistant P. aeruginosa was demonstrated in an in vivo pneumonia model.
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Hetero-Multivalent Targeted Liposomal Drug Delivery to Treat Pseudomonas aeruginosa Infections. ACS APPLIED MATERIALS & INTERFACES 2022; 14:40724-40737. [PMID: 36018830 PMCID: PMC9480101 DOI: 10.1021/acsami.2c12943] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 08/11/2022] [Indexed: 06/15/2023]
Abstract
Pseudomonas aeruginosa is the leading nosocomial and community-acquired pathogen causing a plethora of acute and chronic infections. The Centers for Disease Control and Prevention has designated multidrug-resistant isolates of P. aeruginosa as a serious threat. A novel delivery vehicle capable of specifically targeting P. aeruginosa, and encapsulating antimicrobials, may address the challenges associated with these infections. We have developed hetero-multivalent targeted liposomes functionalized with host cell glycans to increase the delivery of antibiotics to the site of infection. Previously, we have demonstrated that compared with monovalent liposomes, these hetero-multivalent liposomes bind with higher affinity to P. aeruginosa. Here, compared with nontargeted liposomes, we have shown that greater numbers of targeted liposomes are found in the circulation, as well as at the site of P. aeruginosa (PAO1) infection in the thighs of CD-1 mice. No significant difference was found in the uptake of targeted, nontargeted, and PEGylated liposomes by J774.A1 macrophages. Ciprofloxacin-loaded liposomes were formulated and characterized for size, encapsulation, loading, and drug release. In vitro antimicrobial efficacy was assessed using CLSI broth microdilution assays and time-kill kinetics. Lastly, PAO1-inoculated mice treated with ciprofloxacin-loaded, hetero-multivalent targeted liposomes survived longer than mice treated with ciprofloxacin-loaded, monovalent targeted, or nontargeted liposomes and free ciprofloxacin. Thus, liposomes functionalized with host cell glycans target P. aeruginosa resulting in increased retention of the liposomes in the circulation, accumulation at the site of infection, and increased survival time in a mouse surgical site infection model. Consequently, this formulation strategy may improve outcomes in patients infected with P. aeruginosa.
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N-Acetyl cysteine abrogates silver-induced reactive oxygen species in human cells without altering silver-based antimicrobial activity. Toxicol Lett 2020; 332:118-129. [PMID: 32659471 PMCID: PMC7643162 DOI: 10.1016/j.toxlet.2020.07.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 07/07/2020] [Accepted: 07/09/2020] [Indexed: 01/10/2023]
Abstract
Silver-based antimicrobials are widely used topically to treat infections associated with multi-drug resistant (MDR) pathogens. Expanding this topical use to aerosols to treat lung infections requires understanding and preventing silver toxicity in the respiratory tract. A key mechanism resulting in silver-induced toxicity is the production of reactive oxygen species (ROS). In this study, we have verified ROS generation in silver-treated bronchial epithelial cells prompting evaluation of three antioxidants, N-acetyl cysteine (NAC), ascorbic acid, and melatonin, to identify potential prophylactic agents. Among them, NAC was the only candidate that abrogated the ROS generation in response to silver acetate exposure resulting in the rescue of these cells from silver-associated toxicity. Further, this protective effect directly translated to preservation of metabolic activity, as demonstrated by the normal levels of citric acid cycle metabolites in NAC-pretreated silver acetate-exposed cells. Because the citric acid cycle remained functional, silver-exposed cells pre-incubated with NAC demonstrated significantly higher levels of adenosine triphosphate levels compared with NAC-free controls. Moreover, we found that this prodigious capacity of NAC to rescue silver acetate-exposed cells was due not only to its antioxidant activity, but also to its ability to directly bind silver. Despite binding to silver, NAC did not alter the antimicrobial activity of silver acetate.
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Electrospun Antimicrobial, Anti‐Inflammatory and Analgesic Bandages for Comprehensive Wound Treatment. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Pyoverdine-Dependent Virulence of Pseudomonas aeruginosa Isolates From Cystic Fibrosis Patients. Front Microbiol 2019; 10:2048. [PMID: 31551982 PMCID: PMC6743535 DOI: 10.3389/fmicb.2019.02048] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 08/20/2019] [Indexed: 01/03/2023] Open
Abstract
The development of therapies that modulate or prevent pathogen virulence may be a key strategy for circumventing antimicrobial resistance. Toward that end, we examined the production of pyoverdine, a key virulence determinant, in ∼70 Pseudomonas aeruginosa isolates from pediatric cystic fibrosis patients. Pyoverdine production was heterogeneous and showed a clear correlation with pathogenicity in Caenorhabditis elegans and an acute murine pneumonia model. Examination showed pyoverdine accumulation in host tissues, including extrapharyngeal tissues of C. elegans and lung tissues of mice, where accumulation correlated with host death. Many of the isolates tested were resistant to multiple antimicrobials, so we assayed the ability of pyoverdine inhibitors to mitigate virulence and rescue pyoverdine-mediated host pathology. Representatives from three different classes of pyoverdine inhibitors (gallium, fluoropyrimidines, and LK11) significantly improved survival. Our findings highlight the utility of targeting virulence factors in general, and pyoverdine in particular, as a promising method to control bacterial pathogenesis as the utility of antimicrobials continues to diminish.
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Minocycline and Silver Dual-Loaded Polyphosphoester-Based Nanoparticles for Treatment of Resistant Pseudomonas aeruginosa. Mol Pharm 2019; 16:1606-1619. [PMID: 30817887 DOI: 10.1021/acs.molpharmaceut.8b01288] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Pseudomonas aeruginosa has been detected in the lungs of ∼50% of patients with cystic fibrosis (CF), including 20% of adult CF patients. The majority of these adult patients harbor multi-drug resistant (MDR) strains, limiting the available treatment options. Silver has long been used as a broad-spectrum antimicrobial agent with a low incidence of resistance. Despite low toxicity, poor availability of silver cations mandates a high dosage to effectively eradicate infections. To address this shortcoming of silver, nanoparticles have been used as delivery devices to improve treatment outcomes. Furthermore, studies have demonstrated that synergistic combinations with careful dose calibrations and efficient delivery systems result in superior antimicrobial activity while avoiding potential side effects of both therapeutics. Here 4-epi-minocycline, a metabolite of minocycline, was identified as an active antimicrobial against P. aeruginosa using a high-throughput screen. The antimicrobial activities of 4-epi-minocycline, minocycline, and silver acetate against clinical isolates of P. aeruginosa obtained from CF patients were evaluated in vitro. Next, the synergistic activity of the silver/minocycline combination against P. aeruginosa isolates was investigated using checkerboard assays and identified with end-point colony forming unit determination assays. Finally, nanoparticles coloaded with minocycline and silver were evaluated in vitro for antimicrobial activity. The results demonstrated that both silver and minocycline are potent antimicrobials alone and that the combination allows a reduced dosage of both therapeutics to achieve the same antimicrobial effect. Furthermore, the proposed synergistic silver/minocycline combination can be coloaded into nanoparticles as a next-generation antibiotic to combat the threats presented by MDR pathogens.
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Cytoplasmic Localization of BAG-1 in Leukoplakia and Carcinoma of the Tongue: Correlation with p53 and C-Erbb2 in Carcinoma. Int J Biol Markers 2018; 22:100-7. [PMID: 17549665 DOI: 10.1177/172460080702200203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background The present study evaluated the clinical significance of BAG-1, an antiapoptotic protein, in leukoplakia and carcinoma of the tongue. Methods BAG-1 expression was evaluated by immunohistochemistry in paraffin-embedded tissues of leukoplakia (n=25) and carcinoma of the tongue (n=61). Results Cytoplasmic expression was predominantly seen in 80% and 70% of patients with leukoplakia and carcinoma, respectively. BAG-1 expression was found to be significantly lower in tobacco users than in non-tobacco users. BAG-1 expression in tobacco-using leukoplakia and carcinoma patients was compared by grouping the carcinoma patients according to lymph node status and disease stage. Carcinoma patients with tumor-positive lymph nodes had significantly lower BAG-1 expression than patients with negative lymph nodes and leukoplakia. Further, a trend towards an inverse correlation was observed with p53 and c-erbB2. In univariate and multivariate survival analysis, patient subgroups with 2+ or 3+ marker positivity (BAG-1 negativity, p53 and c-erbB2 positivity) had a reduced overall survival compared with patient subgroups with 1+ marker positivity or negativity. Conclusion BAG-1 negativity in association with p53 and c-erbB2 positivity identified a subgroup of tongue cancer patients with an aggressive phenotype. Hence, an antiapoptotic protein, BAG-1, was found to be down-regulated in chewing-tobacco-mediated tongue carcinogenesis.
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Abstract
Chemotherapy, a mainstay modality for cancer, is often hindered by systemic toxicity and side effects. With the emergence of nanomedicine, the development of drug therapy has shifted toward targeted therapy. Hyaluronan (HA) is an ideal molecule as a targeted delivery system because many carcinomas overexpress HA receptors. We have conjugated resveratrol, a natural polyphenol, and 3-(5-methoxy, 2-methyl-1H-indol-3-yl)-1-(4-pyridinyl)-2-propen-1-one (MOMIPP), a chalcone, to HA with the goal of enhancing drug bioavailability and targeting triple negative breast cancers. We demonstrate the ability of HA conjugates to accumulate in the tumor interstitium within 6 h after tail vein injections. In vitro, these conjugates interact with their target receptors, which are overexpressed by triple negative breast cancer cells under static and physiological flow. These interactions result in enhanced uptake and efficacy of the therapeutic, as demonstrated by a reduced IC50 over that of nonconjugated drugs. Thus, HA offers a platform to solubilize, target, and enhance the efficacy of chemotherapeutics.
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Phytochemicals potently inhibit migration of metastatic breast cancer cells. Integr Biol (Camb) 2016; 7:792-800. [PMID: 26120051 DOI: 10.1039/c5ib00121h] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cell migration is a major process that drives metastatic progression of cancers, the major cause of cancer death. Existing chemotherapeutic drugs have limited efficacy to prevent and/or treat metastasis, emphasizing the need for new treatments. We focus on triple negative breast cancer (TNBC), the subtype of breast cancer with worst prognosis and no standard chemotherapy protocols. Here we demonstrate that a group of natural compounds, known as phytochemicals, effectively block migration of metastatic TNBC cells. Using a novel cell micropatterning technology, we generate consistent migration niches in standard 96-well plates where each well contains a cell-excluded gap within a uniform monolayer of cells. Over time, cells migrate into and occupy the gap. Treating TNBC cells with non-toxic concentrations of phytochemicals significantly blocks motility of cells. Using a molecular analysis approach, we show that anti-migratory property of phytochemicals is partly due to their inhibitory effects on phosphorylation of ERK1/2. This study provides a framework for future studies to understand molecular targets of phytochemicals and evaluate their effectiveness in inhibiting metastasis in animal models of cancer.
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Microstereolithography and characterization of poly(propylene fumarate)-based drug-loaded microneedle arrays. Biofabrication 2015; 7:045001. [DOI: 10.1088/1758-5090/7/4/045001] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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FUNCTIONAL LIMITATIONS AND ADIPOKINES IN HIV-INFECTED OLDER ADULTS. J Frailty Aging 2015; 4:41-46. [PMID: 26312240 PMCID: PMC4547479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
BACKGROUND There is a significant increase in the number of HIV-infected older adults (HOA). This population may experience functional decline at a much younger age. Little is known about the relationship between functional limitations and systemic adipokines in HOA. OBJECTIVE Our study aimed to evaluate the relationship between functional limitations and systemic adipokine levels in HOA population. DESIGN Cross-sectional. SETTING Academic hospital-based infectious disease clinic. PARTICIPANTS The study investigated community-dwelling HIV-infected adults >50 years old and compared this group with age, gender and BMI comparable healthy controls. MEASUREMENTS We measured functional status, body composition and plasma concentrations of adipokines. RESULTS Fifty-four HOA were studied (mean: age 57 years, BMI 29 kg/m2, CD4 604, duration of HIV 17 years) and compared with thirty-two age, gender and BMI comparable healthy controls. The HOA group showed significantly higher functional limitations compared to the age, gender and BMI comparable controls (p<0.05). Levels of adipokines were significantly different between the two groups (p<0.05). Multiple regression analyses indicated that adiponectin and visfatin were significantly correlated with several physical function measures after controlling for age, sex, and metabolic comorbidities. Adiponectin was negatively correlated with functional limitations, and this relationship was stronger in the control group compared to the HOA group. Conversely, visfatin was positively correlated with functional limitations only in the HOA group. CONCLUSION HOA have significant functional limitations and alteration in adipokine levels compared to controls. Adiponectin and visfatin were associated with functional limitations. Visfatin was a correlate of physical function only in the HOA group. Prospective longitudinal studies could provide further insight on the role of adipokines in HIV-related functional decline.
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Abstract
The concept of gene therapy is promising; however, the perceived risks and side effects associated with this technology have severely dampened the researchers' enthusiasm. Thus, the development of a nonviral gene vector without immunological effects and with high transfection efficiency is necessary. Currently, most nonviral vectors have failed to achieve the in vivo transfection efficiencies of viral vectors due to their toxicity, rapid clearance, and/or inappropriate release rates. Although our previous studies have successfully demonstrated the controlled-release of plasmid DNA (pDNA) polyplexes encapsulated into nanoparticles formulated with l-tyrosine polyphosphate (LTP-pDNA nanoparticles), the in vivo transfection capabilities and immunogenicity of this delivery system have yet to be examined. Thus, we evaluate LTP-pDNA nanoparticles in an in vivo setting via injection into rodent uterine tissue. Our results demonstrate through X-gal staining and immunohistochemistry of uterine tissue that transfection has successfully occurred after a nine-day incubation. In contrast, the results for the control nanoparticles show results similar to those of shams. Furthermore, reverse transcriptase polymerase chain reaction (RT-PCR) from the injected tissues confirms the transfection in vivo. To examine the immunogenicity, the l-tyrosine polyphosphate (LTP) nanoparticles have been evaluated in a mouse model. No significant differences in the activation of the innate immune system are observed. These data provide the first report for the potential use of controlled-release nanoparticles formulated from an amino acid based polymer as an in vivo nonviral vector for gene therapy.
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Abstract P3-12-07: Voyagers and their aids: The role of interactions between tumor and endothelial cells in brain metastasis. Cancer Res 2012. [DOI: 10.1158/0008-5472.sabcs12-p3-12-07] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Clinically, brain metastases are most commonly observed in breast, lung, and melanoma cancers. When a tumor cell leaves its site of origin, it enters a nearby blood vessel on a voyage to find a new tissue to invade. These circulating tumor cells will act as voyagers and they interact with a endothelial cell. For example, in the case of brain metastasis, tumor cells need to adhere to brain endothelial cells before they can invade into the surrounding brain tissue. Thus, investigating the mechanisms of tumor and endothelial cell interactions can serve as a very powerful tool to inhibit the voyage of these tumor cells and prevent the formation of metastases. In this study, we performed trans-endothelial migration assay using HBMVEC cells to study tumor-endothelial interactions. In general, HBMVEC cells were seeded to BD-Falcon cell culture inserts at a density of 2 × 105 cells and allowed to grow for 24 hours to form a confluent monolayer and GFP expressing tumor cells (MCF-7, Akt3 overexpressing MCF7, MDA-MB-231 and MDA-MB-231-BR) were incubated at suitable interval at 37°C. At the end of incubation period, cells were fixed and number of tumor cells that will penetrate the monolayer of HBMEC were counted using Phase-contrast microscope in 12 different visual fields. Transmigrating tumor cells are thought to be able to overcome the endothelial barrier by inducing changes within endothelial cells. We identified the molecular changes responsible for such adhesion and invasion by cell sorting for gene expression analysis. After co-culturing the HBMEC (after transfecting with Mcherry protein) with GFP expressing tumor cells and Mcherry labeled HBMEC, we used cell sorting to separate tumor and HBMEC cells. After sorting the tumor cells and endothelial cells from co-culture, (MCF-7 monolayer vs MCF-7 co-cultured, MDA-MB-231 monolayer vs MDA-MB-231 co-cultured, HBMEC monolayer vs HBMEC co-cultured) gene expression analysis was performed using SABiosciences cell adhesion assay kit to accurately capture the genetic changes that occured in the tumor and endothelial cells upon co-culture.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-12-07.
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The Interactions between L-tyrosine based nanoparticles decorated with folic acid and cervical cancer cells under physiological flow. Mol Pharm 2012; 9:3089-98. [PMID: 22957928 DOI: 10.1021/mp300221f] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Many anticancer drugs have been established clinically, but their efficacy can be compromised by nonspecific toxicity and an inability to reach the desired cancerous intracellular spaces. In order to address these issues, researchers have explored the use of folic acid as a targeted moiety to increase specificity of chemotherapeutic drugs. To expand upon such research, we have conjugated folic acid to functionalized poly(ethylene glycol) and subsequently decorated the surface of l-tyrosine polyphosphate (LTP) nanoparticles. These nanoparticles possess the appropriate size (100-500 nm) for internalization as shown by scanning electron microscopy and dynamic light scattering. Under simulated physiological flow, LTP nanoparticles decorated with folic acid (targeted nanoparticles) show a 10-fold greater attachment to HeLa, a cervical cancer cell line, compared to control nanoparticles and to human dermal fibroblasts. The attachment of these targeted nanoparticles progresses at a linear rate, and the strength of this nanoparticle attachment is shown to withstand shear stresses of 3.0 dyn/cm(2). These interactions of the targeted nanoparticles to HeLa are likely a result of a receptor-ligand binding, as a competition study with free folic acid inhibits the nanoparticle attachment. Finally, the targeted nanoparticles encapsulated with a silver based drug show increased efficacy in comparison to nondecorated (plain) nanoparticles and drug alone against HeLa cells. Thus, targeted nanoparticles are a promising delivery platform for developing anticancer therapies that overexpress the folate receptors (FRs).
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Kearns Sayre Syndrome--case report with review of literature. Indian J Pediatr 2012; 79:650-4. [PMID: 22231766 DOI: 10.1007/s12098-011-0618-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 11/15/2011] [Indexed: 12/22/2022]
Abstract
Kearns-Sayre Syndrome is form of rare mitochondrial cytopathy, first described by Thomas P. Kearns and George Pomeroy Sayre in 1958 and is characterized by progressive external opthalmoplegia, cardiac conduction block, pigmentary retinal degeneration, variable number of red ragged fibers on muscle biopsy. It presents before the child reaches the age of twenty. Kearns-Sayre syndrome may affect many organ systems and additional features may include myopathy, dystonia, bulbar symptoms in the form of dysarthria and nasal regurgitation and bilateral facial weakness. Endocrine abnormalities (e.g., diabetes, growth retardation/short stature, and hypoparathyroidism), bilateral sensorineural deafness, dementia, cataracts, and proximal renal tubular acidosis, skeletal muscle weakness (proximal more than distal) and exercise intolerance are additional features. Kearns Sayre Syndrome occurs as a result of large-scale single deletions (or rearrangements) of mitochondrial DNA (mtDNA), which is usually not inherited but occurs spontaneously, probably at the germ-cell level or very early in embryonic development. No disease-modifying therapy is available for Kearns-Sayre syndrome (KSS). Management is supportive vigilance for detection of associated problems. In the future, potential treatment in patients with Kearns-Sayre syndrome may attempt to inhibit mutant mtDNA replication or encourage replication of wild-type mtDNA.
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Hemifacial seizures and cerebellar tumor: a rare co-existence. Indian Pediatr 2007; 44:378-9. [PMID: 17536142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We report a 4-year-old boy with multiple daily episodes of abnormal eye movements, hemifacial spasms. Neuro-imaging revealed a cerebellar tumor. We believe that this association constitutes a rare but important syndrome of epilepsy characterized by seizures of cerebellar origin.
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Controversies in febrile seizures. Indian J Pediatr 2000; 67:S71-9. [PMID: 11129896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Febrile seizures are benign, self limiting, common neurological problems encountered in children between 3 months and 5 years. Controversies exist regarding its definition and it is important to distinguish between the terms febrile seizures and convulsions with fever. In the vast majority, febrile seizures occur within the first 24 hours of illness, and an encephalitic process should be considered if it occurs later, especially with exanthema. The temperature threshold varies in the same child and from one child to another. Febrile seizures are classified as simple and complex and debate continues regarding the usage of these terms and their prognostic value. Practice parameters are suggested regarding the performance of lumbar puncture in a child with first febrile seizure, but they should be used as guidelines and the decision depends on the experience and judgement of the physician. EEG is of limited value and not a guide to treatment or prognosis and neuroimaging not recommended. The predictors of recurrent febrile seizures include younger age, lower threshold of temperature, onset within one hour of fever and positive family history. Whether the syndrome of mesial temporal sclerosis beginning with prolonged febrile seizure has a causal relationship with pre existing brain disease is a matter of debate. There are effective therapies to prevent febrile seizures but the potential side effects of drugs outweigh their benefit. Intermittent prophylaxis during fever may be effective but long term prognosis is not influenced by the treatment applied in early childhood. A practical approach to a child with febrile seizure is suggested.
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Does treatment change the outcome of seizures and computerized tomographic lesions in intracranial granulomas? J Trop Pediatr 1999; 45:161-5. [PMID: 10401195 DOI: 10.1093/tropej/45.3.161] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
In children, intracranial granuloma diagnosed on computerized tomography (CT) scan and presenting with seizures as the sole manifestation has traditionally been treated with antitubercular (ATB) therapy or albendazole (Alb) in addition to antiepileptic drugs (AED). This study was conducted to determine whether AED therapy alone or specific treatment (ATB + Alb) influences the outcome of seizures and the CT lesion. Sixty-eight children presenting with seizures along with intracranial granuloma on CT scan were selected for the study. They were randomly divided into two groups. Group A (n = 34) was treated with AED alone and group B (n = 34) received antitubercular therapy and albendazole in addition to AED. Seizure type was noted and electroencephalogram (EEG) and CT scan were done in all. They were followed up for a period of 2 to 9 years, during which a record of seizure count and type was maintained. CT scans were repeated at 3 monthly intervals and EEGs were repeated whenever indicated. Four patients in each group were lost to follow-up. Seizures persisted in four out of 30 in group A and six out of 30 in group B. There was no statistically significant difference (p > 0.05) in the outcome of seizures in the two groups. Taking the whole group together (n = 60), of the 13 who had presented with multiple seizures at onset, epilepsy was a sequela in five (p < 0.05); and of the 17 in whom the lesion had calcified, seizures persisted in seven (p < 0.05), irrespective of treatment modality. In conclusion, though specific treatment did not alter the outcome of seizures, children with multiple seizures at presentation and calcification of CT lesion had epilepsy as a sequela.
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Endoscopic intranasal dacryocystorhinostomy. Indian J Otolaryngol Head Neck Surg 1998; 50:84-5. [PMID: 23119388 PMCID: PMC3451251 DOI: 10.1007/bf02996783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Abstract
Ten children, five boys and five girls with true precocious puberty at an early age were found to have hypothalamic hamartomas on brain imaging. Very early onset of puberty, varying from a few weeks to three years of age, and rapid progression were characteristic. Accelerated growth velocity and markedly advanced bone age were evident in all. Gonadotropin and gonadal hormone levels were elevated above the prepubertal range. Six children had associated developmental delay or hyperactivity.
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Proptosis: management of 22 patients. Indian Pediatr 1993; 30:61-6. [PMID: 8406710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The clinical features and management of 22 cases with proptosis is highlighted. Proptosis was unilateral in fifteen and bilateral in seven cases. The common etiologic factors were neoplasms, infections and bleeding diatheses. Of the ten cases with neoplasms as many as 7 expired, whereas of nine cases due to infections only one expired and one developed phthisis bulbi. All three patients with proptosis due to bleeds recovered completely without sequelae. Orbital CT scan was done in fourteen and ultrasound in eight cases, while in five cases both investigations were done. As neoplasms are a frequent cause of proptosis in children and there is a high mortality in this group, a thorough systemic examination and hematological profile is essential to arrive at a speedy diagnosis. CT and USG are useful imaging modalities of the orbit, the latter being particularly useful for follow up of the lesion.
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Abstract
Venogenic impotence was detected in 37 out of 141 patients who attended our clinic with a complaint of erectile dysfunction. Eighteen patients presented with primary impotence and the rest had progressive secondary impotence. All 37 patients have shown partial or poor response to 60 mg of intracavernosal papaverine. The corporovenous leak (CVL) was diagnosed on the careful workup of dynamic pharmacocavernosometry and cavernosography. Concomitant arterial cause was noted in 10% cases on the basis of penile duplex Doppler ultrasound study. 24 patients in the age group of 23-60 years underwent the penile venous surgery. The CVL was noted in the deep dorsal vein (23 cases), cavernous vein (16) and in the crural vein (2). The operation consisted of deep dorsal vein (DDV) ligation and excision with all tributaries (8 cases) or DDV ligation and excision+cavernous vein ligation (13 cases), through an infrapubic curvilinear incision. One patient had crural vein ligation and corporoplasty through a perineal incision, one had direct corporeal revascularization for associated arteriogenic impotence with venous leak and another had distal spongiolysis and closure of a corporospongiosal shunt. The results were excellent in 11 cases, improved in 6 and 7 had failures. Surgical intervention is effective in CVL in selected cases but limiting factors in the form of increasing age, concomitant arteriogenic cause, significant crural leak, missing tributaries, recurrent venous leak and unknown factors may also be present to prevent total cure.
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Experience with the International League Against Epilepsy classifications of epileptic seizures (1981) and epilepsies and epileptic syndrome (1989) in epileptic children in a developing country. Epilepsia 1992; 33:1072-7. [PMID: 1464266 DOI: 10.1111/j.1528-1157.1992.tb01761.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Four hundred eighty-three epileptic children attending the Pediatric Epilepsy Clinic at Bai Jerbai Wadia Hospital for Children, Bombay, India were classified according to the International League Against Epilepsy (ILAE) classification of epileptic seizures (1981) and epilepsies and epileptic syndromes (1989). The predominant seizures were partial (53.6), generalized (40.3%), and unclassifiable (6%). In epilepsies and epileptic syndromes, 55.3% were partial, 27% were generalized, 13.5% were undetermined, and 4.1% were special syndromes. Although our results were similar in many respects to those of other reported series, some differences were observed in the incidence of partial and generalized seizures, and partial and generalized epileptic syndromes and their subgroups, such as idiopathic, symptomatic, and cryptogenic partial syndromes, idiopathic generalized syndromes, and symptomatic specific syndromes. These differences are probably due to different age limits, methods of case ascertainment and inclusion criteria, different genetic and environmental factors, variable interpretation of clinical and EEG features, and lack of facilities for investigation in developing countries. Despite various limitations, we were able to classify most cases; the ILAE classification can be used in developing countries so that comparison can be made with other studies.
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Abstract
A total of 40 cases of neonatal convulsions of different nonmetabolic aetiological factors were studied. Patients with kernicterus were included in the study. Peak plasma phenobarbital concentrations after incremental loading doses of phenobarbital i.e. 10 mg/kg, 15 mg/kg, and 20 mg/kg were determined. Diphenylhydantoin was added if phenobarbital alone was unable to control seizures. In three patients, a combination of phenobarbital and diphenylhydantoin was used as the initial loading therapy. Increase in the loading dose of phenobarbital was associated with an increase in its peak plasma concentration. Despite increase in the plasma phenobarbital concentration beyond the 'therapeutic' levels suggested by the Western studies, doses of 15 mg/kg and 20 mg/kg of phenobarbital were unable to score over the traditional regimen of 10 mg/kg. Convulsions were controlled in 50% of the patients with any of these three regimens, irrespective of the aetiology. Convulsions were controlled in 7 out of the 9 cases where diphenylhydantoin was added, because of the failure of phenobarbital in controlling the convulsions as a single drug. Convulsions of all the three patients, in whom a combination of phenobarbital and diphenylhydantoin was used by random selection as the initial bolus, were controlled. Seizure effects were difficult to distinguish from drug effects but major side effects were not encountered despite the fluctuating drug levels in the sick neonate.
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26
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Neonatal gastrointestinal perforations. Indian Pediatr 1992; 29:693-8. [PMID: 1500126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Fourteen neonates presented with clinical and radiological evidence of gastrointestinal perforation, of which 13 were treated by operative intervention. No infant was formula fed, had rectal bleeding or radiological evidence of pneumatosis intestinalis. Operative findings revealed localized perforation in ten of which three were gastric, two distal ileal, three cecal and two in sigmoid colon. Gangrene with extensive perforation of jejunum, ascending colon and transverse colon were seen in one each. Blood cultures were positive in four, one grew E. coli and three Klebsiella while peritoneal cultures were positive in six, one grew E. coli and five Klebsiella. Ten neonates survived and are being followed up. Three of the four cases who died had white blood cell count greater than 25 x 109/L and grew Klebsiella on peritoneal culture. Factors predisposing to gastrointestinal perforations in neonates are discussed, emphasis is made on the cautious use of umbilical, gastric and rectal catheters, and the need for early surgical intervention.
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Abstract
Two cases of alobar holoprosencephaly and two of Aicardi syndrome are reported for their highly specific electroencephalographic (EEG) changes. The asynchronous sharp waves and spikes over the frontal regions with decreasing gradient of potential to the occipital leads were seen in alobar holoprosencephaly while burst suppression pattern with total asynchrony between the two hemispheres was seen in Aicardi syndrome. Even though EEG changes cannot be pathognomic of any abnormality, it is suggested that as in conditions like subacute sclerosing panencephalitis and petitmal epilepsy, so also in alobar holoprosencephaly and Aicardi syndrome, the characteristic features seen on EEG may provide the initial clue to the correct diagnosis.
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Abstract
Vesicovaginal fistulae are usually traumatic in nature, following obstetric or gynecologic trauma. Here, our experience with vesicovaginal fistula repair in 68 cases, performed transvesically (58 cases) or transperitoneally-transvesically, with pedicled omental interposition in 10 cases over the last 8 years is described. The size of fistulae ranged from 1 to 5 cm, and most were situated near or above the trigone. Two cases required ureteric reimplantation. Recurrent fistulae were found in 4 cases. We attribute our success to the simple access, the construction of a vascularized flap, the tension-free grid-iron closure, and the utilization of Vicryl suture.
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Abstract
Children of various ages and both sexes (numbering 1,004) attending the out-patient department of Conwest Jain Clinic Group of Hospitals were studied for medication compliance (MC). MC was divided into total, partial, poor and excessive. Various parameters influencing MC like acute or chronic illness, age, sex, community, income, parental education and occupation, number of children, number of family members, form of medicine and number of medicines were studied in details. Only three factors e.g. community, occupation of the father and form of medicine were found to influence MC. No single factor consistently influenced MC. Negligence and poverty play a very important role in MC.
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30
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EEG, CT scan correlation in neurological disorders. Indian Pediatr 1987; 24:401-7. [PMID: 3679491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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31
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Electroencephalographic correlation of clinical, radioisotopic brain scan, CT scan and postmortem diagnosis. Indian J Pediatr 1985; 52:625-31. [PMID: 3836969 DOI: 10.1007/bf02749569] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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32
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33
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Phase I tolerability study of Yogaraj-guggulu--a popular ayurvedic drug. J Postgrad Med 1984; 30:111-5. [PMID: 6527293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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34
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35
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36
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White forelock, pigmentary disorder of irides, and long segment Hirschsprung disease: possible variant of Waardenburg syndrome. J Pediatr 1981; 99:432-5. [PMID: 7264803 DOI: 10.1016/s0022-3476(81)80339-3] [Citation(s) in RCA: 130] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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37
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38
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Pycnodysostosis--case reports of 2 patients. Indian Pediatr 1979; 16:187-90. [PMID: 457234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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39
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Acrodermatitis enteropathica: a case report. Indian Pediatr 1978; 15:511-3. [PMID: 721269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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40
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Chronic idiopathic hyperphosphatasia in an Indian child. AMERICAN JOURNAL OF DISEASES OF CHILDREN (1960) 1973; 126:626-8. [PMID: 4355447 DOI: 10.1001/archpedi.1973.02110190502008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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41
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42
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Idiopathic familial hyperlipaemia (a case report). Indian Pediatr 1971; 8:847-9. [PMID: 5148717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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43
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Ascaris lumbricoides from the right ear. Indian Pediatr 1969; 6:92-3. [PMID: 5783830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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44
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