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1.
J Clin Invest ; 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38687608

ABSTRACT

Dicarboxylic fatty acids are generated in the liver and kidney in a minor pathway called fatty acid ω-oxidation. The effects of consuming dicarboxylic fatty acids as an alternative source of dietary fat have not been explored. Here, we fed dodecanedioic acid, a 12-carbon dicarboxylic (DC12), to mice at 20% of daily caloric intake for nine weeks. DC12 increased metabolic rate, reduced body fat, reduced liver fat, and improved glucose tolerance. We observed DC12-specific breakdown products in liver, kidney, muscle, heart, and brain, indicating that oral DC12 escaped first-pass liver metabolism and was utilized by many tissues. In tissues expressing the "a" isoform of acyl-CoA oxidase-1 (ACOX1), a key peroxisomal fatty acid oxidation enzyme, DC12 was chain shortened to the TCA cycle intermediate succinyl-CoA. In tissues with low peroxisomal fatty acid oxidation capacity, DC12 was oxidized by mitochondria. In vitro, DC12 was catabolized even by adipose tissue and was not stored intracellularly. We conclude that DC12 and other dicarboxylic acids may be useful for combatting obesity and for treating metabolic disorders.

2.
bioRxiv ; 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38496568

ABSTRACT

During corneal wound healing, stromal keratocytes transform into a repair phenotype that is driven by the release of cytokines, like transforming growth factor-beta 1 (TGF-ß1) and platelet-derived growth factor-BB (PDGF-BB). Previous work has shown that TGF-ß1 promotes the myofibroblast differentiation of corneal keratocytes in a manner that depends on PDGF signaling. In addition, changes in mechanical properties are known to regulate the TGF-ß1-mediated differentiation of cultured keratocytes. While PDGF signaling acts synergistically with TGF-ß1 during myofibroblast differentiation, how treatment with multiple growth factors affects stiffness-dependent differences in keratocyte behavior is unknown. Here, we treated primary corneal keratocytes with PDGF-BB and TGF-ß1 and cultured them on polyacrylamide (PA) substrata of different stiffnesses. In the presence of TGF-ß1 alone, the cells underwent stiffness-dependent myofibroblast differentiation. On stiff substrata, the cells developed robust stress fibers, exhibited high levels of ⍺-SMA staining, formed large focal adhesions (FAs), and exerted elevated contractile forces, whereas cells in a compliant microenvironment showed low levels of ⍺-SMA immunofluorescence, formed smaller focal adhesions, and exerted decreased contractile forces. When the cultured keratocytes were treated simultaneously with PDGF-BB however, increased levels of ⍺-SMA staining and stress fiber formation were observed on compliant substrata, even though the cells did not exhibit elevated contractility or focal adhesion size. Pharmacological inhibition of PDGF signaling disrupted the myofibroblast differentiation of cells cultured on substrata of all stiffnesses. These results indicate that treatment with PDGF-BB can decouple molecular markers of myofibroblast differentiation from the elevated contractile phenotype otherwise associated with these cells, suggesting that crosstalk in the mechanotransductive signaling pathways downstream of TGF-ß1 and PDGF-BB can regulate the stiffness-dependent differentiation of cultured keratocytes. Statement of Significance: In vitro experiments have shown that changes in ECM stiffness can regulate the differentiation of myofibroblasts. Typically, these assays involve the use of individual growth factors, but it is unclear how stiffness-dependent differences in cell behavior are affected by multiple cytokines. Here, we used primary corneal keratocytes to show that treatment with both TGF-ß1 and PDGF-BB disrupts the dependency of myofibroblast differentiation on substratum stiffness. In the presence of both growth factors, keratocytes on soft substrates exhibited elevated ⍺-SMA immunofluorescence without a corresponding increase in contractility or focal adhesion formation. This result suggests that molecular markers of myofibroblast differentiation can be dissociated from the elevated contractile behavior associated with the myofibroblast phenotype, suggesting potential crosstalk in mechanotransductive signaling pathways downstream of TGF-ß1 and PDGF-BB.

3.
bioRxiv ; 2024 Mar 03.
Article in English | MEDLINE | ID: mdl-38464034

ABSTRACT

After a stromal injury in the cornea, the release of growth factors and pro-inflammatory cytokines typically results in the activation of quiescent keratocytes toward migratory fibroblast and/or fibrotic myofibroblast phenotypes. The persistence of the myofibroblast phenotype can lead to corneal fibrosis and scarring, which are leading causes of blindness worldwide. The primary goal of this study was to establish comprehensive transcriptional profiles for cultured corneal keratocytes, fibroblasts, and myofibroblasts to gain insights into the mechanisms through which changes in phenotype may occur. Here, we cultured primary rabbit corneal keratocytes on collagen-coated glass coverslips in serum free media (SF), serum containing media (FBS), or in the presence of TGF-ß1 to induce keratocyte, fibroblast, and myofibroblast phenotypes, respectively. Total RNA was collected and sent to Novogene for bulk RNA sequencing. Subsequent bioinformatic analysis included gene expression quantification, differential expression, and functional analysis. When comparing FBS and TGF-ß1 conditions to SF, genes characteristic of a quiescent keratocyte phenotype were downregulated (e.g. KERA, LUM, ALDH1A1), while genes commonly associated with fibroblasts or myofibroblasts were upregulated (e.g. VIM, TNC, FN1, ITGA5, ACTA2). Functional analysis of genes differentially expressed between fibroblasts and keratocytes highlighted pathways related to proliferation (e.g. DNA replication, PI3K-Akt signaling) and cell migration (e.g. Rap1 signaling, ECM-receptor interactions). Enriched pathways for the comparison of myofibroblasts to keratocytes included focal adhesion, regulation of actin cytoskeleton, hippo signaling, and ECM-receptor interaction pathways. Together, these pathways support changes in cytoskeletal organization, cell contractility, mechanotransduction, and cell-ECM interactions in myofibroblasts compared to keratocytes. Overall, these data demonstrate that there are distinct transcriptional differences between cultured corneal keratocytes, fibroblasts, and myofibroblasts. In our initial analysis, we have identified genes and signaling pathways that may play important roles in keratocyte differentiation, including many related to proliferation, cell mechanical activity, and ECM interactions. Furthermore, our findings reveal novel markers for each cell type as well as possible targets for modulating cell behavior and differentiation to promote physiological corneal wound healing.

4.
bioRxiv ; 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38293207

ABSTRACT

Ischemic stroke-induced mitochondrial dysfunction in the blood-brain barrier-forming brain endothelial cells ( BECs ) results in long-term neurological dysfunction post-stroke. We previously reported that intravenous administration of human BEC ( hBEC )-derived mitochondria-containing extracellular vesicles ( EVs ) showed a potential efficacy signal in a mouse middle cerebral artery occlusion ( MCAo ) model of stroke. We hypothesized that EVs harvested from donor species homologous to the recipient species ( e.g., mouse) may improve therapeutic efficacy, and therefore, use of mouse BEC ( mBEC )-derived EVs may improve post-stroke outcomes in MCAo mice. We investigated if EVs derived from the same species as the recipient cell (mBEC-EVs and recipient mBECs or hBECs-EVs and recipient hBECs) show a greater EV mitochondria delivery efficiency than cross-species EVs and recipient cells (mBEC-EVs and recipient hBECs or vice versa ). Our results showed that mBEC-EVs outperformed hBEC-EVs in transferring EV mitochondria to the recipient ischemic mBECs, and improved mBEC mitochondrial function via increasing oxygen consumption rate. mBEC-EVs significantly reduced brain infarct volume and improved behavioral recovery compared to vehicle-injected MCAo mice. Our data suggests that mBEC-EVs show superior therapeutic efficacy in a mouse MCAo stroke model compared to hBEC-EVs-supporting the continued use of mBEC-EVs to optimize the therapeutic potential of mitochondria-containing EVs in preclinical studies.

5.
Epilepsia ; 65(3): 779-791, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38088023

ABSTRACT

OBJECTIVE: Epilepsy with eyelid myoclonia (EEM) spectrum is a generalized form of epilepsy characterized by eyelid myoclonia with or without absences, eye closure-induced seizures with electroencephalographic paroxysms, and photosensitivity. Based on the specific clinical features, age at onset, and familial occurrence, a genetic cause has been postulated. Pathogenic variants in CHD2, SYNGAP1, NEXMIF, RORB, and GABRA1 have been reported in individuals with photosensitivity and eyelid myoclonia, but whether other genes are also involved, or a single gene is uniquely linked with EEM, or its subtypes, is not yet known. We aimed to dissect the genetic etiology of EEM. METHODS: We studied a cohort of 105 individuals by using whole exome sequencing. Individuals were divided into two groups: EEM- (isolated EEM) and EEM+ (EEM accompanied by intellectual disability [ID] or any other neurodevelopmental/psychiatric disorder). RESULTS: We identified nine variants classified as pathogenic/likely pathogenic in the entire cohort (8.57%); among these, eight (five in CHD2, one in NEXMIF, one in SYNGAP1, and one in TRIM8) were found in the EEM+ subcohort (28.57%). Only one variant (IFIH1) was found in the EEM- subcohort (1.29%); however, because the phenotype of the proband did not fit with published data, additional evidence is needed before considering IFIH1 variants and EEM- an established association. Burden analysis did not identify any single burdened gene or gene set. SIGNIFICANCE: Our results suggest that for EEM, as for many other epilepsies, the identification of a genetic cause is more likely with comorbid ID and/or other neurodevelopmental disorders. Pathogenic variants were mostly found in CHD2, and the association of CHD2 with EEM+ can now be considered a reasonable gene-disease association. We provide further evidence to strengthen the association of EEM+ with NEXMIF and SYNGAP1. Possible new associations between EEM+ and TRIM8, and EEM- and IFIH1, are also reported. Although we provide robust evidence for gene variants associated with EEM+, the core genetic etiology of EEM- remains to be elucidated.


Subject(s)
Epilepsy, Generalized , Epilepsy, Reflex , Myoclonus , Humans , Exome Sequencing , Interferon-Induced Helicase, IFIH1/genetics , Epilepsy, Reflex/genetics , Electroencephalography , Eyelids , Carrier Proteins/genetics , Nerve Tissue Proteins/genetics
6.
Nutr Rev ; 2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37837324

ABSTRACT

BACKGROUND: Food provision interventions (eg, produce/food prescriptions, food pharmacies, food voucher programs) that bridge clinic and community settings for improved nutritional health outcomes of at-risk patients have gained momentum. Little is known about the role of nutrition education and potential augmented impact on patient outcomes. OBJECTIVE: To describe intervention designs and outcomes of direct food provision clinic-community programs aimed at improving diabetes-related outcomes (glycated hemoglobin [HbA1c] levels) among patients with type 2 diabetes (T2DM) or prediabetes and food insecurity, and to compare nutrition education components across interventions. METHODS: The PubMed and Academic Search Complete databases were systematically searched for original peer-reviewed articles (published during 2011-2022) that described the impact of clinic-community food provision programs (ie, produce/food prescriptions, food pharmacies, and food voucher programs) onHbA1c values among adults diagnosed with T2DM or prediabetes and who screened positive for food insecurity or low income. Study designs, intervention approaches, program implementation, and intervention outcomes were described. RESULTS: Ten studies representing 8 distinct programs were identified. There was a high degree of variation in the studies' design, implementation, and evaluation. Across the 8 programs, 6 included nutrition education; of these, 1 used a theoretical framework, and 3 incorporated goal setting. Nutrition education covered multiple topical contents, including general nutrition knowledge, fruit and vegetable consumption, and accessing resources (eg, enrolling in the Supplemental Nutrition Assistance Program). Furthermore, the education was delivered through various formats (from 1-on-1 to group-based sessions), educators (community health workers, registered dietitians, physicians), and durations (from a single session to biweekly). All programs with a nutrition education component reported reduced participant HbA1c, and 4 demonstrated an increase in fruit and vegetable purchases or improved dietary quality. The remaining 2 programs that did not include nutrition education yielded mixed results. CONCLUSION: The majority of programs included a nutrition education component; however, there was a high degree of heterogeneity in terms of content, educator, and duration. Patients who participated in programs that included nutrition education had consistent reductions in HbA1c. These observational trends warrant further exploration to conclusively determine the impact of nutrition education on patient outcomes participating in clinic-community food provision programs.

7.
Indian J Palliat Care ; 29(2): 195-199, 2023.
Article in English | MEDLINE | ID: mdl-37325264

ABSTRACT

Objectives: End-stage kidney disease (ESKD) is a life-limiting illness that leads to significant health-related suffering for the patients and their caregivers. Moreover, disease-directed options such as dialysis and renal transplant might not be universally accessible. Inadequate assessment and management of symptoms often lead to diminished quality of life. For evaluating symptoms and their associated distress, various tools have been identified. However, these are not available for the native Kannada-speaking population for assessing ESKD symptom burden. In this study, we determined the reliability and validity of the Edmonton Symptom Assessment System Revised Renal (ESAS-r: Renal) in Kannada-speaking ESKD patients. Materials and Methods: ESAS-r: Renal English version was translated into Kannada using the forward and backward method. The translated version was endorsed by Nephrology, Palliative care, Dialysis technology and Nursing experts. As a pilot study, 12 ESKD patients evaluated the content of the questionnaires for appropriateness and relevance. The ESAS-r: Renal Kannada version was validated by administering this tool to 45 patients twice a fortnight. Result: The translated ESAS-r: Renal Kannada version questionnaire had an acceptable face and content validity. Experts' opinion was assessed by content validity ratio (CVR), and the value of CVR of ESAS-r: Renal Kannada version was-'1'-. Internal consistency of the tool was assessed among Kannada-speaking ESKD patients; its Cronbach's α was 0.785, and test-retest validity was 0.896. Conclusion: The validated Kannada version of ESAS-r: Renal was reliable and valid for assessing symptom burden in ESKD patients.

8.
Cell Mol Biol Lett ; 28(1): 22, 2023 Mar 18.
Article in English | MEDLINE | ID: mdl-36934253

ABSTRACT

BACKGROUND: Cerebral arteriovenous malformations (cAVM) are a significant cause of intracranial hemorrhagic stroke and brain damage. The arteriovenous junctions in AVM nidus are known to have hemodynamic disturbances such as altered shear stress, which could lead to endothelial dysfunction. The molecular mechanisms coupling shear stress and endothelial dysfunction in cAVMs are poorly understood. We speculated that disturbed blood flow in artery-vein junctions activates Notch receptors and promotes endothelial mesenchymal plasticity during cAVM formation. METHODS: We investigated the expression profile of endothelial mesenchymal transition (EndMT) and cell adhesion markers, as well as activated Notch receptors, in 18 human cAVM samples and 15 control brain tissues, by quantitative real-time PCR (qRT-PCR) and immunohistochemical evaluation. Employing a combination of a microfluidic system, qRT-PCR, immunofluorescence, as well as invasion and inhibitor assays, the effects of various shear stress conditions on Notch-induced EndMT and invasive potential of human cerebral microvascular endothelial cells (hCMEC/d3) were analyzed. RESULTS: We found evidence for EndMT and enhanced expression of activated Notch intracellular domain (NICD3 and NICD4) in human AVM nidus samples. The expression of transmembrane adhesion receptor integrin α9/ß1 is significantly reduced in cAVM nidal vessels. Cell-cell adhesion proteins such as VE-cadherin and N-cadherin were differentially expressed in AVM nidus compared with control brain tissues. Using well-characterized hCMECs, we show that altered fluid shear stress steers Notch3 nuclear translocation and promotes SNAI1/2 expression and nuclear localization. Oscillatory flow downregulates integrin α9/ß1 and VE-cadherin expression, while N-cadherin expression and endothelial cell invasiveness are augmented. Gamma-secretase inhibitor RO4929097, and to a lesser level DAPT, prevent the mesenchymal transition and invasiveness of cerebral microvascular endothelial cells exposed to oscillatory fluid flow. CONCLUSIONS: Our study provides, for the first time, evidence for the role of oscillatory shear stress in mediating the EndMT process and dysregulated expression of cell adhesion molecules, especially multifunctional integrin α9/ß1 in human cAVM nidus. Concomitantly, our findings indicate the potential use of small-molecular inhibitors such as RO4929097 in the less-invasive therapeutic management of cAVMs.


Subject(s)
Endothelial Cells , Intracranial Arteriovenous Malformations , Humans , Endothelial Cells/metabolism , Intracranial Arteriovenous Malformations/metabolism , Receptors, Notch/metabolism , Cadherins/genetics , Cadherins/metabolism , Epithelial-Mesenchymal Transition
9.
Indian J Palliat Care ; 28(3): 272-279, 2022.
Article in English | MEDLINE | ID: mdl-36072250

ABSTRACT

Objectives: Palliative care (PC) referral in serious and critical COVID-19 improves decision-making, health resource utilisation, end-of-life symptom management and family support. In this study, we explored developing a systematic decision-making matrix for PC referral in COVID-19 and audited its outcomes. Materials and Methods: A team of interdisciplinary experts developed a hospital COVID-19 PC plan. PC referral and outcomes of PC referral in hospitalised COVID-19 patients were audited. Results: Out of 1575 inpatients, 1066 (67.7%) had mild and 509 (32.3%) had serious and critical COVID-19 illness. Among 50 (3.1%) referred to PC, 5 (0.4%) had mild and 45 (8.8%) had serious and critical COVID-19 illness. Out of 45 serious and critical COVID-19 patients referred to PC, 38 (84%) received end-of-life care (EOLC), 4 (9%) self-discharged against medical advice and 3 (7%) recovered. Forty-seven (94%) were referred for goals-of-care discussion. About 78% received opioids, 70% benzodiazepines and 42% haloperidol for symptom management. Among 45 serious and critical COVID-19 patients referred to PC, foregoing life-sustaining treatment was documented in 43 (96%) but implemented only in 23 (53%). Out of 38 who received EOLC, ICU was the place of death in 31 (82%) and ward in 7 (18%). Conclusion: Despite interdisciplinary experts developing a hospital COVID-19 PC, low referral of serious and critical COVID-19 patients to PC was observed. PC referral enabled access to management of end-of-life symptoms and facilitated limitation of life-sustaining treatment in some COVID-19 patients with serious illness. Educating critical care physicians about the scope of PC in the COVID-19 setting might improve PC referral.

10.
Front Cell Dev Biol ; 10: 886759, 2022.
Article in English | MEDLINE | ID: mdl-35693927

ABSTRACT

Following injury and refractive surgery, corneal wound healing can initiate a protracted fibrotic response that interferes with ocular function. This fibrosis is related, in part, to the myofibroblast differentiation of corneal keratocytes in response to transforming growth factor beta 1 (TGF-ß1). Previous studies have shown that changes in the mechanical properties of the extracellular matrix (ECM) can regulate this process, but the mechanotransductive pathways that govern stiffness-dependent changes in keratocyte differentiation remain unclear. Here, we used a polyacrylamide (PA) gel system to investigate how mechanosensing via focal adhesions (FAs) regulates the stiffness-dependent myofibroblast differentiation of primary corneal keratocytes treated with TGF-ß1. Soft (1 kPa) and stiff (10 kPa) PA substrata were fabricated on glass coverslips, plated with corneal keratocytes, and cultured in defined serum free media with or without exogenous TGF-ß1. In some experiments, an inhibitor of focal adhesion kinase (FAK) activation was also added to the media. Cells were fixed and stained for F-actin, as well as markers for myofibroblast differentiation (α-SMA), actomyosin contractility phosphorylated myosin light chain (pMLC), focal adhesions (vinculin), or Smad activity (pSmad3). We also used traction force microscopy (TFM) to quantify cellular traction stresses. Treatment with TGF-ß1 elicited stiffness-dependent differences in the number, size, and subcellular distribution of FAs, but not in the nuclear localization of pSmad3. On stiff substrata, cells exhibited large FAs distributed throughout the entire cell body, while on soft gels, the FAs were smaller, fewer in number, and localized primarily to the distal tips of thin cellular extensions. Larger and increased numbers of FAs correlated with elevated traction stresses, increased levels of α-SMA immunofluorescence, and more prominent and broadly distributed pMLC staining. Inhibition of FAK disrupted stiffness-dependent differences in keratocyte contractility, FA patterning, and myofibroblast differentiation in the presence of TGF-ß1. Taken together, these data suggest that signaling downstream of FAs has important implications for the stiffness-dependent myofibroblast differentiation of corneal keratocytes.

11.
Exp Eye Res ; 220: 109112, 2022 07.
Article in English | MEDLINE | ID: mdl-35595094

ABSTRACT

During corneal wound healing, keratocytes present within the corneal stroma become activated into a repair phenotype upon the release of growth factors, such as transforming growth factor-beta 1 (TGF-ß1) and platelet-derived growth factor-BB (PDGF-BB). The process of injury and repair can lead to changes in the mechanical properties of the tissue, and previous work has shown that the TGF-ß1-mediated myofibroblast differentiation of corneal keratocytes depends on substratum stiffness. It is still unclear, however, if changes in stiffness can modulate keratocyte behavior in response to other growth factors, such as PDGF-BB. Here, we used a polyacrylamide (PA) gel system to determine whether changes in stiffness influence the proliferation and motility of primary corneal keratocytes treated with PDGF-BB. In the presence of PDGF-BB, cells on stiffer substrata exhibited a more elongated morphology and had higher rates of proliferation than cells in a more compliant microenvironment. Using a freeze-injury to assay cell motility, however, we did not observe any stiffness-dependent differences in the migration of keratocytes treated with PDGF-BB. Taken together, these data highlight the importance of biophysical cues during corneal wound healing and suggest that keratocytes respond differently to changes in ECM stiffness in the presence of different growth factors.


Subject(s)
Corneal Keratocytes , Transforming Growth Factor beta1 , Becaplermin/pharmacology , Cell Movement , Cell Proliferation , Cells, Cultured , Platelet-Derived Growth Factor
12.
Cell Stem Cell ; 29(5): 840-855.e7, 2022 05 05.
Article in English | MEDLINE | ID: mdl-35395180

ABSTRACT

Hypoplastic left heart syndrome (HLHS) is a severe congenital heart disease with 30% mortality from heart failure (HF) in the first year of life, but the cause of early HF remains unknown. Induced pluripotent stem-cell-derived cardiomyocytes (iPSC-CM) from patients with HLHS showed that early HF is associated with increased apoptosis, mitochondrial respiration defects, and redox stress from abnormal mitochondrial permeability transition pore (mPTP) opening and failed antioxidant response. In contrast, iPSC-CM from patients without early HF showed normal respiration with elevated antioxidant response. Single-cell transcriptomics confirmed that early HF is associated with mitochondrial dysfunction accompanied with endoplasmic reticulum (ER) stress. These findings indicate that uncompensated oxidative stress underlies early HF in HLHS. Importantly, mitochondrial respiration defects, oxidative stress, and apoptosis were rescued by treatment with sildenafil to inhibit mPTP opening or TUDCA to suppress ER stress. Together these findings point to the potential use of patient iPSC-CM for modeling clinical heart failure and the development of therapeutics.


Subject(s)
Heart Defects, Congenital , Heart Failure , Induced Pluripotent Stem Cells , Antioxidants/metabolism , Heart Defects, Congenital/metabolism , Heart Failure/metabolism , Humans , Mitochondrial Permeability Transition Pore , Myocytes, Cardiac/metabolism , Oxidative Stress
13.
Stem Cells ; 40(2): 204-214, 2022 03 16.
Article in English | MEDLINE | ID: mdl-35257185

ABSTRACT

Transplantation of stem/progenitor cells holds promise for cardiac regeneration in patients with myocardial infarction (MI). Currently, however, low cell survival and engraftment after transplantation present a major barrier to many forms of cell therapy. One issue is that ligands, receptors, and signaling pathways that promote graft success remain poorly understood. Here, we prospectively isolate uncommitted epicardial cells from the adult heart surface by CD104 (ß-4 integrin) and demonstrate that C-terminal peptide from connective tissue growth factor (CTGF-D4), when combined with insulin, effectively primes epicardial-derived cells (EPDC) for cardiac engraftment after MI. Similar to native epicardial derivatives that arise from epicardial EMT at the heart surface, the grafted cells migrated into injured myocardial tissue in a rat model of MI with reperfusion. By echocardiography, at 1 month after MI, we observed significant improvement in cardiac function for animals that received epicardial cells primed with CTGF-D4/insulin compared with those that received vehicle-primed (control) cells. In the presence of insulin, CTGF-D4 treatment significantly increased the phosphorylation of Wnt co-receptor LRP6 on EPDC. Competitive engraftment assays and neutralizing/blocking studies showed that LRP6 was required for EPDC engraftment after transplantation. Our results identify LRP6 as a key target for increasing EPDC engraftment after MI and suggest amplification of LRP6 signaling with CTGF-D4/insulin, or by other means, may provide an effective approach for achieving successful cellular grafts in regenerative medicine.


Subject(s)
Connective Tissue Growth Factor/metabolism , Insulins , Myocardial Infarction , Animals , Heart , Humans , Low Density Lipoprotein Receptor-Related Protein-6/metabolism , Myocardial Infarction/metabolism , Myocardial Infarction/therapy , Myocardium/metabolism , Rats
14.
Front Bioeng Biotechnol ; 10: 749787, 2022.
Article in English | MEDLINE | ID: mdl-35295649

ABSTRACT

Hepatocyte Growth Factor (HGF) and Fibroblast Growth Factor 2 (FGF2) are receptor tyrosine kinase agonists that promote cell survival after tissue injury and angiogenesis, cell proliferation and migration during tissue repair and regeneration. Both ligands have potential as systemic treatments for ischemia-reperfusion injury, however clinical use of HGF and FGF2 has been limited by poor pharmacokinetic profiles, i.e., their susceptibility to serum proteases, rapid clearance and short half-lives. Previously, we reported vaso- and cardioprotective protein complexes formed between HGF and polyclonal, non-specific immunoglobulin (IgG) with therapeutic efficacy in a rat model of myocardial ischemia with reperfusion (MI/R). Here, using a pre-clinical porcine MI/R model, we demonstrate human HGF/IgG complexes provide significant myocardial salvage, reduce infarct size, and are detectable in myocardial tissue 24 h after intracoronary injection. Furthermore, we show that multiple daily infusions of HGF/IgG complexes after MI do not lead to production of HGF-specific auto-antibodies, an important concern for administered biologic drugs. In experiments to identify other growth factors that non-covalently interact with IgG, we found that human FGF2 associates with IgG. Similar to human HGF/IgG complexes, FGF2/IgG complexes protected primary human cardiac endothelial cells under simulated ischemia (1% oxygen and nutrient deprivation) for 48-72 h. Molecular modeling studies suggested that FGF2 and HGF both interact with the Fc domain of IgG. Also, we tested whether an Fc-fusion protein would bind FGF2 to form complexes. By native gel electrophoretic assays and biochemical pulldowns, we found that Jagged1, a Notch1 ligand that controls stem cell self-renewal and tissue regeneration, bound FGF2 when presented as a Jagged1- Fc fusion protein. Our results suggest that human growth factor/IgG and FGF2/Fc- fusion complexes have potential to provide a biologics platform to treat myocardial ischemia-reperfusion and other forms of tissue injury.

15.
Indian J Palliat Care ; 27(3): 439-441, 2021.
Article in English | MEDLINE | ID: mdl-34898938

ABSTRACT

Maggots are dipterous larvae of flies. Infestation of vertebrate animals (including humans) by maggots is termed as Myiasis. Warm and Humid climate, low socio-economic status, lack of knowledge and poor living conditions, malignant wounds predispose the cancer patients to maggot infestation in India. Apart from infestation in the wounds; oral, ophthalmic, nasal, aural, enteric, urogenital, trachea-pulmonary and rectal myiasis have been reported. Maggot infestation of the Intercostal drain (ICD) container without associated pleural myiasis is an extremely rare entity. We describe a rare case report of maggots in the ICD in a patient with metastatic chondrosarcoma femur with ICD in situ for malignant pleural effusion. Early detection and management are the keys to prevent the catastrophic complication of pleural myiasis.

16.
Polymers (Basel) ; 13(19)2021 Sep 27.
Article in English | MEDLINE | ID: mdl-34641118

ABSTRACT

Polyhydroxyalkanoates (PHAs) are storage granules found in bacteria that are essentially hydroxy fatty acid polyesters. PHA molecules appear in variety of structures, and amongst all types of PHAs, polyhydroxybutyrate (PHB) is used in versatile fields as it is a biodegradable, biocompatible, and ecologically safe thermoplastic. The unique physicochemical characteristics of these PHAs have made them applicable in nanotechnology, tissue engineering, and other biomedical applications. In this review, the optimization, extraction, and characterization of PHAs are described. Their production and application in nanotechnology are also portrayed in this review, and the precise and various production methods of PHA-based nanoparticles, such as emulsion solvent diffusion, nanoprecipitation, and dialysis are discussed. The characterization techniques such as UV-Vis, FTIR, SEM, Zeta Potential, and XRD are also elaborated.

17.
Front Neurol ; 12: 722664, 2021.
Article in English | MEDLINE | ID: mdl-34566868

ABSTRACT

The developmental and epileptic encephalopathies (DEE) are the most severe group of epilepsies. Recently, NEXMIF mutations have been shown to cause a DEE in females, characterized by myoclonic-atonic epilepsy and recurrent nonconvulsive status. Here we used advanced neuroimaging techniques in a patient with a novel NEXMIF de novo mutation presenting with recurrent absence status with eyelid myoclonia, to reveal brain structural and functional changes that can bring the clinical phenotype to alteration within specific brain networks. Indeed, the alterations found in the patient involved the visual pericalcarine cortex and the middle frontal gyrus, regions that have been demonstrated to be a core feature in epilepsy phenotypes with visual sensitivity and eyelid myoclonia with absences.

18.
Indian J Palliat Care ; 27(2): 286-290, 2021.
Article in English | MEDLINE | ID: mdl-34511798

ABSTRACT

OBJECTIVES: Early integrated palliative care has shown to improve the quality of life in patients with cancer. During the past decade, pediatric palliative care has become an established area of medical expertise, however due to scant information available regarding the triggers for referral and referral practice very few children receive a formal palliative care consult. MATERIALS AND METHODS: A retrospective audit of medical case records of pediatric oncology patients over a period of 1 year from September 30, 2019, to September 30, 2020, was conducted. Demographic details, diagnosis, staging, clinical parameters, reason for referral, and palliative care plan were captured in a predesigned pro forma. RESULTS: Among 126 children with cancer, 27 (21.4%) patients were referred to palliative care. Majority 21 (77%) referrals were inpatient consults. Symptom management 17 (44.7%) was the most common trigger for referral followed by referrals for psychosocial support 12 (14.4%). Children with solid tumors 16 (59%) were more often referred than hematological malignancies. Among those needing end of life care, 8 (88.8%) out of 9 families preferred home than hospital. CONCLUSION: Low incidence of palliative care referral and presence of symptoms as a trigger for palliative care referral suggests gaps in the integrated approach. The study findings prompt a review of palliative care referral criteria and referral practice in a pediatric oncology setting.

19.
Indian J Palliat Care ; 27(Suppl 1): S6-S10, 2021 May.
Article in English | MEDLINE | ID: mdl-34188372

ABSTRACT

The decision regarding dialysis initiation is complex. Awareness that renal replacement therapy should not be regarded as default therapy for every patient with advanced renal failure is necessary. Decision to initiate dialysis and modality should be individualized in a shared decision-making process involving the treating nephrologist and the patient. Patients should receive predialysis education early in the course of chronic kidney disease so as to help prepare them well in advance for this eventuality. Withholding dialysis may be a reasonable option in a certain subset of patients, especially elderly patient with multiple co-morbid illnesses. Comprehensive conservation care should be offered in all patients where the decision to not dialyze is taken.

20.
Neurology ; 96(11): e1539-e1550, 2021 03 16.
Article in English | MEDLINE | ID: mdl-33504645

ABSTRACT

OBJECTIVE: To explore the phenotypic spectrum of RHOBTB2-related disorders and specifically to determine whether patients fulfill criteria for alternating hemiplegia of childhood (AHC), we report the clinical features of 11 affected individuals. METHODS: Individuals with RHOBTB2-related disorders were identified through a movement disorder clinic at a specialist pediatric center, with additional cases identified through collaboration with other centers internationally. Clinical data were acquired through retrospective case-note review. RESULTS: Eleven affected patients were identified. All had heterozygous missense variants involving exon 9 of RHOBTB2, confirmed as de novo in 9 cases. All had a complex motor phenotype, including at least 2 different kinds of movement disorder, e.g., ataxia and dystonia. Many patients demonstrated several features fulfilling the criteria for AHC: 10 patients had a movement disorder including paroxysmal elements, and 8 experienced hemiplegic episodes. In contrast to classic AHC, commonly caused by mutations in ATP1A3, these events were reported later only in RHOBTB2 mutation-positive patients from 20 months of age. Seven patients had epilepsy, but of these, 4 patients achieved seizure freedom. All patients had intellectual disability, usually moderate to severe. Other features include episodes of marked skin color change and gastrointestinal symptoms, each in 4 patients. CONCLUSION: Although heterozygous RHOBTB2 mutations were originally described in early infantile epileptic encephalopathy type 64, our study confirms that they account for a more expansive clinical phenotype, including a complex polymorphic movement disorder with paroxysmal elements resembling AHC. RHOBTB2 testing should therefore be considered in patients with an AHC-like phenotype, particularly those negative for ATPA1A3 mutations.


Subject(s)
GTP-Binding Proteins/genetics , Hemiplegia/genetics , Tumor Suppressor Proteins/genetics , Adolescent , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Mutation, Missense , Phenotype , Young Adult
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