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1.
Bioeng Transl Med ; 9(1): e10615, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38193111

ABSTRACT

Long-term patient and graft survival has been achieved in organ transplantation but at the expense of toxic side effects that are associated with long-term use of nonspecific immunosuppressive drugs. Discovering new regulators of dendritic cells is the key for development of an ideal treatment to prevent immune rejection. We hypothesized that knockdown of circMAP2K2 induces immunosuppressive DCs and that treatment with circMAP2K2 silenced-DCs can prevent alloimmune rejection. DCs were cultured and transfected with siRNA for circMAP2K2. circMAP2K2 levels were measured by qRT-PCR. DC's maturation and immune function were assessed by flow cytometry and mixed lymphocyte reactions. The function of circMAP2K2 was illustrated by a series of RIP and IP. The therapeutics of engineered DCs was tested in a mouse heart transplantation model. We found that circMAP2K2 was highly expressed in mature DCs. Knockdown of circMAP2K2 reduced expression of MHCII, CD40 and CD80, attenuated the ability of DCs to activate allogeneic naïve T cells, and enhanced CD4+CD25+FOXP3+ regulatory T cells (Treg). circMAP2K2-induced immunosuppressive DCs by interacting with SENP3. Treatment with circMAP2K2-knockdown DCs attenuated alloimmune rejection and prolonged allograft survival in a murine heart transplantation model. The immune suppression induced in vivo was donor-antigen specific. In conclusion, knockdown of circMAP2K2 can induce immunosuppressive DCs which are able to inhibit overactive immune response, highlighting a new promising therapeutic approach for immune disorder diseases.

2.
J Pharm Investig ; 53(1): 19-33, 2023.
Article in English | MEDLINE | ID: mdl-36568502

ABSTRACT

Background: In recent decades, there has been a considerable increase in the number of nanomedicine-based formulations, and their advantages, including controlled/targeted drug delivery with increased efficacy and reduced toxicity, make them ideal candidates for therapeutic delivery in the treatment of complex and difficult-to-treat diseases, such as cancer. Areas covered: This review focuses on nanomedicine-based formulation development, approved and marketed nanomedicines, and the challenges faced in nanomedicine development as well as their future prospects. Expert opinion: To date, the Food and Drug Administration and the European Medicines Agency have approved several nanomedicines, which are now commercially available. However, several critical challenges, including reproducibility, proper characterization, and biological evaluation, e.g., via assays, are still associated with their use. Therefore, rigorous studies alongside stringent guidelines for effective and safe nanomedicine development and use are still warranted. In this study, we provide an overview of currently available nanomedicine-based formulations. Thus, the findings here reported may serve as a basis for further studies regarding the use of these formulations for therapeutic purposes in near future.

3.
Eur J Pharm Sci ; 166: 105990, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34481880

ABSTRACT

Superficial infections in chronic wounds can prevent the wound healing process by the development of persistent infections and drug-resistant biofilms. Topically applied antimicrobial formulations with stabilized and controlled release offer significant benefits for the effective treatment of wound infections. Bacteriocins are the antimicrobial peptides (AMPs) produced by bacteria that are viable alternatives to antibiotics owing to their natural origin and low propensity for resistance development. Herein, we developed a hybrid hydrogel composed of Pluronic F127 (PF127), ethylenediaminetetraacetic acid (EDTA) loaded liposomes, glutathione (GSH), and the bacteriocin Garvicin KS (GarKS) referred to as "GarKS gel". The GarKS gel exhibited suitable viscosity and rheological properties along with controlled release behavior (up to 9 days) for effective peptide delivery following topical application. Potent in vitro antibacterial and anti-biofilm effects of GarKS gel were evident against the Gram-positive bacterium Staphylococcus aureus. The in vivo treatment of methicillin resistant S. aureus (MRSA) infected mouse wounds suggested potent antibacterial effects of the GarKS gel following multiple applications of once-a-day application for three consecutive days. Altogether, these results provide proof-of-concept for the successful development of AMP loaded topical formulation for effective treatment of wound infections.


Subject(s)
Bacteriocins , Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Wound Infection , Animals , Anti-Bacterial Agents , Hydrogels , Mice , Staphylococcal Infections/drug therapy , Wound Infection/drug therapy
4.
Front Med Technol ; 3: 685686, 2021.
Article in English | MEDLINE | ID: mdl-35047932

ABSTRACT

Recently, proteins are gaining attention as potential materials for antibacterial therapy. Proteins possess beneficial properties such as biocompatibility, biodegradability, low immunogenic response, ability to control drug release, and can act as protein-mimics in wound healing. Different plant- and animal-derived proteins can be developed into formulations (films, hydrogels, scaffolds, mats) for topical antibacterial therapy. The application areas for topical antibacterial therapy can be wide including bacterial infections in the skin (e.g., acne, wounds), eyelids, mouth, lips, etc. One of the major challenges of the healthcare system is chronic wound infections. Conventional treatment strategies for topical antibacterial therapy of infected wounds are inadequate, and the development of newer and optimized formulations is warranted. Therefore, this review focuses on recent advances in protein-based systems for topical antibacterial therapy in infected wounds. The opportunities and challenges of such protein-based systems along with their future prospects are discussed.

5.
Eur J Pharm Sci ; 158: 105652, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33248238

ABSTRACT

There is a growing interest in the use of antimicrobial peptides (AMPs) as potent alternatives for conventional antibiotics, especially in chronic infected wounds. The development of a suitable topical formulation requires a thorough assessment of the photostability profiles of AMPs. In this study, we sought to investigate the photostability of novel Garvicin KS (GarKS; composed of three peptides GakA, GakB, and GakC) peptides either as an individual peptide or in combinations. The photostability of the aqueous peptide solution was determined using Suntest (indoor and outdoor conditions). Furthermore, the antimicrobial efficacy of the peptides was evaluated following UVA irradiations. Photodegradation of the peptides under indoor and outdoor conditions followed first-order kinetics. Individual peptides (GakA, GakB, and GakC) were more prone to photodegradation as compared to combination peptides (GakA+GakB, GakB+GakC, and GakA+GakC) both under indoor and outdoor conditions where the GakA+GakB combination was the most photostable. A combination of GakA+GakB+GakC enhanced photostability under indoor conditions but was reduced under outdoor conditions. A combination of three peptides with an antioxidant (glutathione) or superoxide/hydrogen peroxide scavenger (trehalose) enhanced the photostability of peptides with the highest stability achieved at a peptide:photostabilizer molar ratio of 1:0.8 for glutathione. A nominal increase in the MIC value for the peptide combinations as opposed to a larger increase for individual peptides further supports the photostability effects of combination peptides following UVA irradiations. These results suggest that the GakA+GakB or GakA+GakB+GakC combinations exhibited the highest photostability with excellent antimicrobial efficacy deemed suitable for the development of a potent AMP formulation for topical applications.


Subject(s)
Anti-Infective Agents , Ultraviolet Rays , Antioxidants , Peptides , Photolysis
6.
Clin Infect Dis ; 73(7): e1478-e1486, 2021 10 05.
Article in English | MEDLINE | ID: mdl-32991678

ABSTRACT

BACKGROUND: Azithromycin and trimethoprim-sulfamethoxazole (SXT) are widely used to treat undifferentiated febrile illness (UFI). We hypothesized that azithromycin is superior to SXT for UFI treatment, but the drugs are noninferior to each other for culture-confirmed enteric fever treatment. METHODS: We conducted a double-blind, randomized, placebo-controlled trial of azithromycin (20 mg/kg/day) or SXT (trimethoprim 10 mg/kg/day plus sulfamethoxazole 50 mg/kg/day) orally for 7 days for UFI treatment in Nepal. We enrolled patients >2 years and <65 years of age presenting to 2 Kathmandu hospitals with temperature ≥38.0°C for ≥4 days without localizing signs. The primary endpoint was fever clearance time (FCT); secondary endpoints were treatment failure and adverse events. RESULTS: From June 2016 to May 2019, we randomized 326 participants (163 in each arm); 87 (26.7%) had blood culture-confirmed enteric fever. In all participants, the median FCT was 2.7 days (95% confidence interval [CI], 2.6-3.3 days) in the SXT arm and 2.1 days (95% CI, 1.6-3.2 days) in the azithromycin arm (hazard ratio [HR], 1.25 [95% CI, .99-1.58]; P = .059). The HR of treatment failures by 28 days between azithromycin and SXT was 0.62 (95% CI, .37-1.05; P = .073). Planned subgroup analysis showed that azithromycin resulted in faster FCT in those with sterile blood cultures and fewer relapses in culture-confirmed enteric fever. Nausea, vomiting, constipation, and headache were more common in the SXT arm. CONCLUSIONS: Despite similar FCT and treatment failure in the 2 arms, significantly fewer complications and relapses make azithromycin a better choice for empirical treatment of UFI in Nepal. CLINICAL TRIALS REGISTRATION: NCT02773407.


Subject(s)
Azithromycin , Typhoid Fever , Anti-Bacterial Agents/therapeutic use , Azithromycin/therapeutic use , Double-Blind Method , Humans , Nepal , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Typhoid Fever/drug therapy
7.
Carbohydr Polym ; 249: 116815, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32933663

ABSTRACT

Hyaluronic acid (HA) assisted effective internalization into CD44 receptor-overexpressing cancer cells, which could offer an excellent cytotoxic profile and tumor alterations. In this study, duo-photothermal agents (copper sulfide (CuS) and graphene oxide (GO)), chemotherapeutic drug (doxorubicin (DOX)), and targeting moiety (HA) were incorporated into a complexed nanoconstruct for trio-responsive chemo-phototherapy. The nanosystem (CuS(DOX)-GO-HA) was demonstrating its responsive drug release and escalated photothermal behavior. The hyperthermia and photodynamic effect were observed along with efficient ROS generation in the presence of dual photosensitizers. The in vivo biodistribution and photothermal profile reflected a high accumulation and retention of the nanoconstruct in the tumor. Importantly, nanoconstructs effectively inhibit tumor growth based on tumor volume analysis and the altered expression of apoptosis, cell proliferation, and angiogenesis markers. Collectively, these findings suggest that this nanoconstruct has excellent antitumor effects in CD44 overexpressed cells showing the potential for clinical translation in the future.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , Breast Neoplasms/therapy , Carcinoma, Squamous Cell/therapy , Doxorubicin/pharmacology , Hyaluronic Acid/administration & dosage , Nanoparticles/administration & dosage , Photochemotherapy , Animals , Antibiotics, Antineoplastic/chemistry , Apoptosis , Breast Neoplasms/pathology , Carcinoma, Squamous Cell/pathology , Cell Proliferation , Combined Modality Therapy , Copper/chemistry , Doxorubicin/chemistry , Female , Graphite/chemistry , Humans , Hyaluronic Acid/chemistry , Mice , Mice, Inbred BALB C , Mice, Nude , Nanoparticles/chemistry , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
8.
ACS Appl Bio Mater ; 3(6): 3500-3517, 2020 Jun 15.
Article in English | MEDLINE | ID: mdl-32656505

ABSTRACT

Wound healing is a complex biological process that requires coordinated cell proliferation, migration, and extracellular matrix production/remodeling, all of which are inhibited/delayed in chronic wounds. In this study, a formulation was developed that marries a fibrin-based, provisional-like matrix with collagen mimetic peptide (CMP)/PDGF gene-modified collagens, leading to the formation of robust gels that supported temporally controlled PDGF expression and facile application within the wound bed. Analysis employing in vitro co-gel scaffolds confirmed sustained and temporally controlled gene release based on matrix metalloproteinase (MMP) activity, with ~30% higher PDGF expression in MMP producing fibroblasts as-compared with non-MMP-expressing cells. The integration of fibrin with the gene-modified collagens resulted in co-gels that strongly supported both fibroblast cell recruitment/invasion as well as multiple aspects of the longer-term healing process. The excisional wound healing studies in mice established faster wound closure using CMP-modified PDGF polyplex-loaded co-gels, which exhibited up to 24% more wound closure (achieved with ~2 orders of magnitude lower growth factor dosing) after 9 days as compared to PDGF-loaded co-gels, and 19% more wound closure after 9 days as compared to CMP-free polyplex loaded co-gels. Moreover, minimal scar formation as well as improved collagen production, myofibroblast activity, and collagen orientation was observed following CMP-modified PDGF polyplex-loaded co-gel application on wounds. Taken together, the combined properties of the co-gels, including their stability and capacity to control both cell recruitment and cell phenotype within the murine wound bed, strongly supports the potential of the co-gel scaffolds for improved treatment of chronic non-healing wounds.

9.
Colloids Surf B Biointerfaces ; 195: 111250, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32659650

ABSTRACT

The drug solubilization capacity of poloxamers like Pluronic F127 (PF127, poloxamer 407) is dependent on the physical form of the polymer; i.e. the distribution between unimers, aggregates, and micelles. Further, the formation of micelles can alter the stability and pharmacological activity of a drug molecule. It is therefore important to understand how the micellization process is influenced by the addition of excipients and drug molecules. Curcumin is considered a photosensitizer in antimicrobial photodynamic therapy (aPDT). The aPDT effect is optimized at a poloxamer concentration just below the critical micellar concentration (CMC). We aimed to evaluate the effect of curcumin in the presence of 1% ethanol (EtOH) or dimethyl sulfoxide (DMSO) on PF127 micellization. These organic solvents are commonly used in topical preparations as a cosolvent or penetration enhancer (in the case of DMSO). The micellization process was investigated by UV-vis spectroscopy, dynamic light scattering (DLS), and differential scanning calorimetry (DSC). The micellization process of PF127 was slightly influenced by the addition of 1% EtOH or DMSO; however, the presence of 20 µM curcumin enhanced the effect. Micellization was favored in PBS compared to MilliQ water. Structures were formed between PF127 and curcumin at poloxamer concentrations ≥0.3 µM which facilitated solubilization of the photosensitizer. The optimal PF127 concentration required to solubilize 20 µM curcumin but avoid micellization was in the range 0.3 µM-0.04 mM in PBS in the presence of 1 % EtOH or DMSO. A careful consideration of the curcumin, cosolvents, and PF127 concentrations is required to enhance the curcumin solubility and prevent the PF127 micellization.


Subject(s)
Curcumin , Poloxamer , Curcumin/pharmacology , Micelles , Solubility , Water
10.
Eur J Pharm Sci ; 151: 105333, 2020 Aug 01.
Article in English | MEDLINE | ID: mdl-32268197

ABSTRACT

Antimicrobial peptides (AMPs) are emerging as a viable alternative to antibiotics attributable to their potent antimicrobial effects and low propensity for resistance development, especially in chronic infected wounds. The development of an optimized topical formulation of AMPs is thus warranted. Preformulation studies for determination of the suitability and optimization requirements of AMPs in topical formulation development are important. Therefore, we sought to investigate the preformulation studies for a novel bacteriocin garvicin KS (GarKS), which is composed of three peptides (GakA, GakB, and GakC). The effects of physiological fluids and varying temperatures on GarKS peptide stability were determined. The antimicrobial effects of the peptides and their combinations were evaluated in Staphylococcus aureus (methicillin sensitive and resistant strains). Furthermore, their effects on fibroblast viability and proliferation were determined. The GarKS peptides were stable in water and PBS at room and physiological temperatures, however, the peptides were significantly degraded in simulated wound fluid. The antimicrobial and fibroblast cell viability/proliferation effects of either individual GarKS peptides or their combinations varied. A careful consideration of the peptide stability, antimicrobial efficacy, and fibroblast viability/proliferation effects suggests GakA+GakB as a potent combination for the development of an optimized topical formulation of GarKS peptides.


Subject(s)
Anti-Infective Agents , Staphylococcal Infections , Anti-Bacterial Agents/pharmacology , Humans , Microbial Sensitivity Tests , Peptides/pharmacology , Staphylococcus aureus
11.
Expert Opin Drug Deliv ; 17(3): 423-434, 2020 03.
Article in English | MEDLINE | ID: mdl-32028805

ABSTRACT

Background: Phytosterols significantly reduce the risk of cancer by directly inhibiting tumor growth, inducing apoptosis, and inhibiting tumor metastasis. Stigmasterol (STS), a phytosterol, exhibits anticancer effects against various cancers, including breast cancer. Chemotherapeutics, including doxorubicin (DOX), might act synergistically with phytosterol against the proliferation and metastasis of breast cancer. Although such compounds can show potential anticancer activity, their combined effect with suitable formulation has not investigated yet.Methods: Hyaluronic acid (HA)-modified PEGylated DOX-STS loaded phyto-liposome was fabricated via a thin-film hydration method. The prepared phyto-liposome was optimized with regards to its physicochemical and other properties. Further, in vitro and in vivo study was carried out in breast cancer cells expressing a different level of CD44 receptors.Results: The particle size of prepared HA-DOX-STS-lipo was 173.9 ± 2.4 nm, and showed pH-depended DOX release, favoring the effective tumor targetability. The in vitro anticancer activity of HA-DOX-STS-lipo was significantly enhanced in MDA-MB-231, CD44-overexpressing cells relative to MCF-7 cells demonstrating HA-mediated targeting effect. HA-DOX-STS-lipo accumulated more and increased antitumor efficacy in the MDA-MB-231 xenograft tumor model expressing high levels of CD44, suggesting the potential of carrier system toward CD44-overexpressing tumors.


Subject(s)
Breast Neoplasms/drug therapy , Doxorubicin/analogs & derivatives , Phytosterols/administration & dosage , Animals , Apoptosis/drug effects , Cell Line, Tumor , Doxorubicin/administration & dosage , Drug Delivery Systems , Female , Humans , Hyaluronan Receptors/metabolism , Hyaluronic Acid/chemistry , Liposomes , MCF-7 Cells , Male , Mice, Inbred BALB C , Mice, Nude , Particle Size , Polyethylene Glycols/administration & dosage , Polyethylene Glycols/chemistry , Rats , Rats, Sprague-Dawley , Xenograft Model Antitumor Assays
12.
JNMA J Nepal Med Assoc ; 58(232): 998-1004, 2020 Dec 31.
Article in English | MEDLINE | ID: mdl-34506388

ABSTRACT

INTRODUCTION: Voluntary blood donation is a reliable source of increasing the demand for blood transfusion. Medical students are the potential pool of blood donors. This study aims to find the prevalence of blood donation practice among medical students of a medical college in Nepal. METHODS: This is a descriptive cross-sectional study conducted in a medical college of Nepal among students studying from the first year to final year MBBS. Ethical approval was obtained from the Institutional Review Committee of the Nepalese Army Institute of Health Sciences (Ref no. 245). A stratified random sampling technique was used to collect data. A self-administered pre-tested questionnaire was used to collect data. Data were analyzed using Microsoft Excel 2016. RESULTS: The prevalence of blood donation practice among medical students of the medical college is 41 (22.20%) (17.35-27.05 at 95% Confidence Interval). The practice of blood donation is seen more among students of the final year 15 (35.71%) and the least among first year 3 (8.57%). Most of the donors, 24 (58.54%), have donated blood only once before. The most common reasons for donating and not donating blood before are 'behavior of altruism' 12 (29.27%) and 'I am not fit/disapproved' 44 (30.56%) respectively. CONCLUSIONS: This study shows less prevalence of blood donation practice among medical students. It points to the need for more extensive studies to explore the factors deterring medical students from donating blood. Definitive strategies are also needed to encourage medical students to increased voluntary participation in blood donation.


Subject(s)
Blood Donors , Students, Medical , Cross-Sectional Studies , Health Knowledge, Attitudes, Practice , Humans , Surveys and Questionnaires , Tertiary Care Centers
13.
Acta Biomater ; 103: 115-128, 2020 02.
Article in English | MEDLINE | ID: mdl-31843720

ABSTRACT

Wound infections are a significant clinical problem affecting millions of people worldwide. Topically applied antibacterial formulations with longer residence time and controlled antimicrobial release would offer significant benefits for improved prevention and treatment of infected wounds. In this study, we developed collagen mimetic peptide (CMP) tethered vancomycin (Van)-containing liposomes (Lipo) (CMP-Van-Lipo) hybridized to collagen-based hydrogels ('co-gels,' e.g., collagen/fibrin combination hydrogels) for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections in vitro and in vivo. Tethering CMP-Van-Lipo nanostructures to co-gels enabled sustained Van release and enhanced in vitro antibacterial effects against MRSA as compared to Van loaded co-gels or Van-Lipo loaded co-gels following multiple fresh bacterial inoculations over a period of 48 h. These results were successfully translated in vivo wherein MRSA infected wounds were effectively treated with CMP-Van-Lipo loaded co-gels for up to 9 days, whereas the activity of Van loaded co-gels and Van-Lipo loaded co-gels were limited to <2 days. Moreover, CMP-Van-Lipo retained in vivo antibacterial activity even after re-inoculation with bacteria; however, Van loaded co-gels and Van-Lipo loaded co-gels allowed significant bacterial growth demonstrating their limited efficacy. Altogether, these results provide proof-of-concept that CMP-Van-Lipo loaded co-gels can be effective topical formulations for preventive treatment of MRSA wound infections. STATEMENT OF SIGNIFICANCE: Current topical antimicrobial formulations (e.g., creams, gels, and ointments) do not control release, leaving antimicrobial concentrations either too high or too low at different time points, and provoking the development of antibacterial resistance and recurrence of wound infections. Here, collagen mimetic peptides (CMPs) were used to stably hybridize vancomycin-containing liposomal nanocarriers (CMP-Van-Lipo) within collagen-fibrin co-gels via triple-helical integration with collagen, enabling control over Van release for prolonged time periods and minimizing the adverse effects of the Lipo formulations on fibroblast cell viability in the wound bed. The CMP-Van-Lipo loaded co-gel's higher antibacterial effects in vitro were successfully translated in vivo for treatment of MRSA-infected mouse wounds, and thus the co-gels can be a potentially translatable treatment for improved clinical wound management.


Subject(s)
Biomimetic Materials/therapeutic use , Collagen/chemistry , Infection Control , Peptides/chemistry , Tissue Scaffolds/chemistry , Vancomycin/therapeutic use , Wound Infection/drug therapy , Animals , Anti-Bacterial Agents/pharmacology , Cattle , Cell Survival/drug effects , Disease Models, Animal , Drug Liberation , Gels , Liposomes , Male , Methicillin-Resistant Staphylococcus aureus/drug effects , Mice , Mice, Inbred BALB C , Microbial Sensitivity Tests , NIH 3T3 Cells , Rats, Sprague-Dawley , Skin/drug effects , Skin/microbiology , Skin/pathology , Vancomycin/pharmacology , Wound Infection/microbiology , Wound Infection/pathology
14.
Acta Biomater ; 103: 52-67, 2020 02.
Article in English | MEDLINE | ID: mdl-31874224

ABSTRACT

Antimicrobial peptides (AMPs) are the natural antibiotics recognized for their potent antibacterial and wound healing properties. Bare AMPs have limited activity following topical application attributable to their susceptibility to environment (hydrolysis, oxidation, photolysis), and wound (alkaline pH, proteolysis) related factors as well as minimal residence time. Therefore, the formulation of AMPs is essential to enhance stability, prolong delivery, and optimize effectiveness at the wound site. Different topical formulations of AMPs have been developed so far including nanoparticles, hydrogels, creams, ointments, and wafers to aid in controlling bacterial infection and enhance wound healing process in vivo. Herein, an overview is provided of the AMPs and current understanding of their formulations for topical wound healing applications along with suitable examples. Furthermore, future prospects for the development of effective combination AMP formulations are discussed. STATEMENT OF SIGNIFICANCE: Chronic wound infection and subsequent development of antibiotic resistance are serious clinical problems affecting millions of people worldwide. Antimicrobial peptides (AMPs) possess great potential in effectively killing the bacteria with minimal risk of resistance development. However, AMPs susceptibility to degradation following topical application limits their antimicrobial and wound healing effects. Therefore, development of an optimized topical formulation with high peptide stability and sustained AMP delivery is necessary to maximize the antimicrobial and wound healing effects. The present review provides an overview of the state-of-art in the field of topical AMP formulations for wound healing. Current developments in the field of topical AMP formulations are reviewed and future prospects for the development of effective combination AMP formulations are discussed.


Subject(s)
Pore Forming Cytotoxic Proteins/administration & dosage , Pore Forming Cytotoxic Proteins/pharmacology , Wound Healing/drug effects , Administration, Topical , Animals , Clinical Trials as Topic , Drug Compounding , Humans , Microbial Sensitivity Tests
15.
Curr Opin Chem Eng ; 24: 143-157, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31844607

ABSTRACT

The use of hydrogels in biomedical applications dates back multiple decades, and the engineering potential of these materials continues to grow with discoveries in chemistry and biology. The approaches have led to increasing complex hydrogels that incorporate both synthetic and natural polymers and functional domains for tunable release kinetics, mediated cell response, and ultimately use in clinical and research applications in biomedical practice. This review focuses on recent advances in hybrid hydrogels that incorporate nano/microstructures, their synthesis, and applications in biomedical research. Examples discussed include the implementation of click reactions, photopatterning, and 3D printing for the facile production of these hybrid hydrogels, the use of biological molecules and motifs to promote a desired cellular outcome, and the tailoring of kinetic and transport behavior through hybrid-hydrogel engineering to achieve desired biomedical outcomes. Recent progress in the field has established promising approaches for the development of biologically relevant hybrid hydrogel materials with potential applications in drug discovery, drug/gene delivery, and regenerative medicine.

16.
Theranostics ; 9(23): 6780-6796, 2019.
Article in English | MEDLINE | ID: mdl-31660068

ABSTRACT

Several therapeutic nanosystems have been engineered to remedy the shortcomings of cancer monotherapies, including immunotherapy (stimulating the host immune system to eradicate cancer), to improve therapeutic efficacy with minimizing off-target effects and tumor-induced immunosuppression. Light-activated components in nanosystems confer additional phototherapeutic effects as combinatorial modalities; however, systemic and thermal toxicities with unfavorable accumulation and excretion of nanoystem components now hamper their practical applications. Thus, there remains a need for optimal multifunctional nanosystems to enhance targeted, durable, and mild combination therapies for efficient cancer treatment without notable side effects. Methods: A nanosystem constructed with a base core (poly-L-histidine [H]-grafted black phosphorus [BP]) and a shell (erythrocyte membrane [EM]) is developed to offer a mild photoresponsive (near-infrared) activity with erythrocyte mimicry. In-flight electrostatic tailoring to extract uniform BP nanoparticles maintains a hydrodynamic size of <200 nm (enabling enhanced permeability and retention) after EM cloaking and enhances their biocompatibility. Results: Ephrin-A2 receptor-specific peptide (YSA, targeting cancer cells), interleukin-1α silencing small interfering RNA (ILsi, restricting regulatory T cell trafficking), and paclitaxel (X, inducing durable chemotherapeutics) are incorporated within the base core@shell constructs to create BP-H-ILsi-X@EM-YSA architectures, which provide a more intelligent nanosystem for combination cancer therapies. Conclusion: The in-flight tailoring of BP particles provides a promising base core for fabricating <200 nm EM-mimicking multifunctional nanosystems, which could be beneficial for constructing smarter nanoarchitectures to use in combination cancer therapies.


Subject(s)
Antineoplastic Agents, Phytogenic/administration & dosage , Nanoparticles/chemistry , Neoplasms, Experimental/therapy , Paclitaxel/administration & dosage , Phosphorus/chemistry , RNAi Therapeutics/methods , Animals , Antineoplastic Agents, Phytogenic/therapeutic use , Cell Line, Tumor , Cell Membrane/chemistry , Combined Modality Therapy/methods , Erythrocytes/chemistry , Histidine/chemistry , Interleukin-1alpha/genetics , Interleukin-1alpha/metabolism , Mice , Mice, Inbred C57BL , Nanoparticles/adverse effects , Neoplasms, Experimental/drug therapy , Paclitaxel/therapeutic use
17.
Nanomedicine ; 21: 102042, 2019 10.
Article in English | MEDLINE | ID: mdl-31247311

ABSTRACT

Targeted, biocompatible, and synergistic "all in one" systems should be designed to combat the heterogeneity of cancer. In this study, we constructed a dual function nanosystem, copper sulfide nanoplatform loaded with the chemotherapeutic drug docetaxel wrapped by a conjugated polymer-peptide for targeted chemo-phototherapy. The nanoconstruct has been successfully designed with a size of 186.1 ±â€¯5.2 nm, a polydispersity index of 0.18 ±â€¯0.01, and zeta potential of -16.4 ±â€¯0.1 mV. The enhanced uptake and near-infrared-responsive behavior of the nanosystem resulted in efficient drug release, photothermal ablation, effective cytotoxic activity, and potentiated reactive oxygen species generation. The induction of apoptotic markers, enhanced accumulation in the tumor site, and maximum tumor growth inhibition were seen during in vivo studies compared to non-targeted nanoformulations and free drug. Cumulatively, our results indicate that, with low systemic toxicity and better biocompatibility, this nanoconstruct could provide a promising strategy for treating prostate cancer.


Subject(s)
Doxorubicin/pharmacology , Drug Delivery Systems , Polymers/pharmacology , Prostatic Neoplasms/drug therapy , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/radiation effects , Cell Proliferation/drug effects , Copper/chemistry , Doxorubicin/chemistry , Drug Liberation/radiation effects , Humans , Hyperthermia, Induced , Male , Nanoparticles/chemistry , Peptides/chemistry , Peptides/pharmacology , Peptides, Cyclic/chemistry , Peptides, Cyclic/pharmacology , Phototherapy , Polymers/chemistry , Polymers/radiation effects , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Reactive Oxygen Species/chemistry , Receptors, Somatostatin/genetics , Somatostatin/analogs & derivatives , Somatostatin/chemistry , Somatostatin/pharmacology , Sulfides/chemistry
18.
Plant Direct ; 3(1): e00100, 2019 Jan.
Article in English | MEDLINE | ID: mdl-31245749

ABSTRACT

The Polycomb Group (PcG) proteins form two protein complexes, PcG Repressive Complex 1 (PRC1) and PRC2, which are key epigenetic regulators in eukaryotes. PRC2 represses gene expression by catalyzing the trimethylation of histone H3 lysine 27 (H3K27me3). In Arabidopsis (Arabidopsis thaliana), CURLY LEAF (CLF) and SWINGER (SWN) are two major H3K27 methyltransferases and core components of PRC2, playing essential roles in plant growth and development. Despite their importance, genome-wide binding profiles of CLF and SWN have not been determined and compared yet. In this study, we generated transgenic lines expressing GFP-tagged CLF/SWN under their respective native promoters and used them for ChIP-seq analyses to profile the genome-wide distributions of CLF and SWN in Arabidopsis seedlings. We also profiled and compared the global H3K27me3 levels in wild-type (WT) and PcG mutants (clf, swn, and clf swn). Our data show that CLF and SWN bind to almost the same set of genes, except that SWN has a few hundred more targets. Two short DNA sequences, the GAGA-like and Telo-box-like motifs, were found enriched in the CLF and SWN binding regions. The H3K27me3 levels in clf, but not in swn, were markedly reduced compared with WT; and the mark was undetectable in the clf swn double mutant. Further, we profiled the transcriptomes in clf, swn, and clf swn, and compared that with WT. Thus this work provides a useful resource for the plant epigenetics community for dissecting the functions of PRC2 in plant growth and development.

19.
JNMA J Nepal Med Assoc ; 57(215): 20-24, 2019.
Article in English | MEDLINE | ID: mdl-31080240

ABSTRACT

INTRODUCTION: An earthquake is an intense shaking of earth's surface which is caused by movements in earth's outermost layer. The earthquake of 25th April 2015, with a magnitude of 7.8 richter scale with its major aftershock on 12th May 2015 of 7.3 richter scale claimed around 8,962 lives across several districts of Nepal with 22,302 injuries. In this study we tried to figure out various surgical cases and the surgical procedures performed in a tertiary care hospital during an earthquake disaster. METHODS: This study was a descriptive cross-sectional study of hospital data on all admitted surgical cases during an earthquake disaster. A total of 238 earthquake victims brought to emergency department of Kathmandu Medical College Teaching Hospital , a tertiary care center, from 26th April 2015 to 7th Jun 2015, for the period of 42 days were included. Those brought dead and discharged after primary treatments were excluded. Data obtained were entered and analysed in Microsoft Excel 2010. RESULTS: Among 238 patients enrolled, 122 (51%) were male and 116 (49%) female with male to female ratio of 1.05:1. Age group (31-60 years) with an average age of 45 years were encountered most frequently 110 (46%) with the maximum number of patient burden from Sindhupalchowk district 80 (33.6%). Orthopedic surgery 185 (76%) appeared to be the most frequent followed by neurosurgery, plastic surgery, general surgery and dental surgery. CONCLUSIONS: In natural disaster like earthquakes, traumatic injuries are very common and thereby various surgical procedures especially ortho-plastic are the domain of treatment modalities. Disaster preparedness and combined surgical team effort needs to be focused to reduce both mortality and morbidity.


Subject(s)
Disasters , Earthquakes , Surgical Procedures, Operative/statistics & numerical data , Wounds and Injuries/surgery , Adult , Cross-Sectional Studies , Emergency Service, Hospital , Female , Hospitalization , Humans , Male , Middle Aged , Nepal , Tertiary Care Centers , Wounds and Injuries/epidemiology
20.
JNMA J Nepal Med Assoc ; 57(215): 33-36, 2019.
Article in English | MEDLINE | ID: mdl-31080243

ABSTRACT

INTRODUCTION: Cardiomyopathies are diseases of heart muscle that may originate from genetic defects, cardiac myocyte injury or infiltration of myocardial tissues. Dilated cardiomyopathy is the most common phenotype and is often a final common pathway of numerous cardiac insults. Mostly it remains unknown in the absence of echocardiography, histopathology and genetic evaluation. Though common it is underdiagnosed with not much of data available in our setup. METHODS: This study was analytical cross-sectional study of hospital data on Echocardiographic findings in 65 patients of DCM visiting cardiology unit for Echocardiographic evaluation from 1st of February to 31st July 2018 for the period of six months in Shree Birendra Hospital, a tertiary care military hospital at Chhauni, Kathmandu. Pediatric age group patients and those who refused to give consent were excluded. Data obtained were entered in Microsoft Excel 2010 and analyzed by IBM SPSS 21. RESULTS: Among 65 patients enrolled 40 (61%) were male and 25 (39%) female with male to female ratio of 1.6:1. Elderly people (61-75 years) with an average age of 65 were commonly involved and they presented mostly with congestive heart failure, 32 (49%). Echocardiographic evaluation showed 36 (55%) with mildly dilated Left Ventricle (5.6-6.0cm). Majority had reduced Left ventricular systolic function with an average Ejection fraction (EF) of 39.6%. No significant difference between male and female with the average EF% (P=0.990) and there was no significant relation between age and average EF% (P=0.091). CONCLUSIONS: Dilated Cardiomyopathy is the commonest cardiomyopathy phenotype mostly presenting with congestive heart failure. It is often underdiagnosed in our part of the world, however echocardiography will easily detect the condition.


Subject(s)
Cardiomyopathy, Dilated/diagnostic imaging , Echocardiography/methods , Heart Failure/epidemiology , Stroke Volume/physiology , Aged , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Nepal , Tertiary Care Centers , Ventricular Dysfunction, Left/epidemiology
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