Accelerating healing of infected wounds with G. glabra extract and curcumin Co-loaded electrospun nanofibrous dressing.

This study aimed to construct a nanofibrous wound dressing composed of polyvinyl alcohol (PVA) and chitosan (CS) containing curcumin and Glycyrrhiza glabra root extract to inhibit infection and accelerate wound healing. Loading 10 wt% of G. glabra extract-curcumin (50:50) by electrospinng technique resulted in the formation of nanofibers (NFs) with diameter distribution 303 ± 38 and had a uniform and defect-free morphology. FTIR analysis confirmed the loading of the components without adverse interactions. Also, the results showed extremely high porosity, extraordinary liquid absorption capacity, and complete wettability. In addition, G. glabra extract-curcumin showed significant antioxidant activity and their release profile from NFs was continuous and sustained. Also, the prepared NF could inhibit the growth of both Gram-positive Saureus and Gram-negative E. coli strains. Wound healing evaluation in the infected animal model showed that the NFs caused full wound closure and accelerated skin regeneration. The studies on inhibiting the bacteria growth at the wound site also revealed complete inhibitory effects. Moreover, histopathology studies confirmed the complete regeneration of skin layers, formation of collagen fibers, and angiogenesis. Finally, PVA/CS NFs containing G. glabra extract-curcumin as a multifunctional bioactive wound dressing presented a promising approach for promoting the healing of infected wounds.

The potential role of Hypericum perforatum in wound healing: A literature review on the phytochemicals, pharmacological approaches, and mechanistic perspectives.

St. John's Wort, commonly known as Hypericum perforatum L., is a flowering plant in the Clusiaceae family that traditionally been employed for treating anxiety, depression, wounds, burns, sunburn, irritation, and stomach ailments. This review provides a synopsis of H. perforatum L. phytoconstituents and their biological effects, highlighting its beneficial therapeutic properties for dermatological indications, as well as its antioxidant, antimicrobial, anti-inflammatory, and anti-angiogenic activity in various applications including wound healing and skin conditions such as eczema, sun burn and minor burns also spastic paralysis, stiff neck and mood disorders as anti-depressant and nerve pains such as neuralgia. The data were collected from several databases as Web of Science PubMed, ScienceDirect, Scopus and Google Scholar using the terms: "H. perforatum L.", "H. perforatum L. /phytochemistry," and "H. perforatum extracts/wound healing" collected from 1994 to 2023. The findings suggest H. perforatum L. acts through various mechanisms and plays a role in each phase of the wound healing process, including re-epithelialization, angiogenesis, wound contraction, and connective tissue regeneration. H. perforatum L. enhances collagen deposition, decreases inflammation, inhibits fibroblast migration, and promotes epithelialization by increasing the number of fibroblasts with polygonal shape and the number of collagen fibers within fibroblasts. H. Perforatum L. extracts modulate the immune response and reduce inflammation were found to accelerate the wound healing process via inhibition of inflammatory mediators' production like interleukin-6, tumor necrosis factor-α, cyclooxygenase-2 gene expression, and inducible nitric oxide synthase. Thus, H. perforatum L. represents a potential remedy for a wide range of dermatological problems, owing to its constituents with beneficial therapeutic properties. H. perforatum L. could be utilized in the development of novel wound healing therapies.

Zingiber officinale and thymus vulgaris extracts co-loaded polyvinyl alcohol and chitosan electrospun nanofibers for tackling infection and wound healing promotion.

Infections are severe complications associated with chronic wounds and tardy healing that should be timely treated to achieve rapid and proper tissue repair. To hinder such difficulties, a nanofibrous mat composed of polyvinyl alcohol and chitosan (PVA/CS) was developed by electrospinning method, containing thyme (Thymus vulgaris) and ginger (Zingiber officinale) extracts. The mat containing 10 wt% of the extracts (at the ratio of 50:50) exposed the nanofibers (NFs) with the nanoscale diameter (average 382 ± 60 nm), smooth surface, and defect-free morphology. Likewise, the relevant analyses of the loaded mat displayed high wettability, porosity, and liquid absorption capacity without any adverse interaction. The obtained mat also provided a high antioxidant activity, and its release profile was continuous and sustained for nearly 72 h. Besides, it inhibited the growth of both Gram-positive S. aureus and Gram-negative E. coli strains. Furthermore, the proposed mat significantly accelerated cutaneous wound healing in bacterial-infected rats by preventing bacteria growth at the wound site. At last, histopathology analysis confirmed the ample regeneration of skin structures, forming collagen fibers and appendages. Overall, the proposed mat containing ginger-thyme extracts provides multiple therapeutic capabilities with promising solutions for inhibiting wound infection and accelerating the healing process.

Demographic and biological factors in interrelationships between physical, cognitive, psychological, and social frailty in community-dwelling older adults: Data from the Birjand Longitudinal Aging Study (BLAS).

Complex interrelationships may exist among different types of frailty. This study aimed to evaluate the demographic and biological factors that influence the different types of frailty in community-dwelling older adults in Iran through a cross-sectional analysis of data obtained from the Birjand Longitudinal Aging Study. This study is an ongoing cohort study of people aged 60 years and over and employed a multistage stratified cluster random sampling. Anthropometric measures were obtained by nurses. The "Fried frailty phenotype" was defined as physical frailty. Cognitive frailty was assessed using the Mini-Mental State Examination. Social frailty was evaluated by some questions, and psychological frailty was assessed using a patient health questionnaire. Blood samples were taken after overnight fasting. All statistical analyses were performed using Stata12 (Texas, USA) and Python. Some type of frailty had been experienced by 62.27 % of the older adults. Cognitive frailty was the dominant type of frailty (55.69 %). Based on multivariate regression analysis, age, sex, education, and marital status were the influencing factors in all types of frailty. Network analysis revealed that physical, cognitive, psychological, and social frailty had synergistic effects on each other, and age and sex had dominant interactions with frailty types. Cognitive frailty was dominant compared with other types of frailty, indicating the need to detect cognitive frailty at the earliest stage and to implement an appropriate program to manage cognitive frailty in older adults.

Diabetic stem cell therapy and nanomedicine: advancements in treating diabetes.

Objectives: In recent years, significant advancements have been made in the field of medical sciences, particularly in the treatment of diabetes using innovative methods. Diabetes, a chronic metabolic disorder considered by elevated blood glucose levels, disturbs millions of people worldwide. Methods: Conventional treatments for diabetes have shown limited success in providing long-term solutions, leading researchers to explore alternative therapies such as diabetic stem cell therapy and nanomedicine. In this article, we delve into the promising potential of these cutting-edge treatments and their impact on diabetes management. Results: Several achievements have been obtained to treat diabetes type I by merging nanomedicine and cell therapy such as insulin-loaded exosomes and nanoparticles loaded with different drugs. For instance, by engineering exosomes with specific nanocarriers, researchers can precisely deliver some molecules to target cells, promoting tissue repair and regeneration. Conclusions: It seems that using nanomedicine and cell therapy, we can explore the inventive way for a future somewhere diabetes is no longer a problem for millions, and people can hold a great quality life.

Bromelain- and Silver Nanoparticle-Loaded Polycaprolactone/Chitosan Nanofibrous Dressings for Skin Wound Healing.

A cutaneous wound is caused by various injuries in the skin, which can be wrapped with an efficient dressing. Electrospinning is a straightforward adjustable technique that quickly and continuously generates nanofibrous wound dressings containing antibacterial and anti-inflammatory agents to promote wound healing. The present study investigated the physicochemical and biological properties of bromelain (BRO)- and silver nanoparticle (Ag NPs)-loaded gel-based electrospun polycaprolactone/chitosan (PCL/CS) nanofibrous dressings for wound-healing applications. Electron microscopy results showed that the obtained nanofibers (NFs) had a uniform and homogeneous morphology without beads with an average diameter of 176 ± 63 nm. The FTIR (Fourier transform infrared) analysis exhibited the loading of the components. Moreover, adding BRO and Ag NPs increased the tensile strength of the NFs up to 4.59 MPa. BRO and Ag NPs did not significantly affect the hydrophilicity and toxicity of the obtained wound dressing; however, the antibacterial activity against E. coli and S. aureus bacteria was significantly improved. The in vivo study showed that the wound dressing containing BRO and Ag NPs improved the wound-healing process within one week compared to other groups. Therefore, gel-based PCL/CS nanofibrous dressings containing BRO and Ag NPs could be a promising solution for healing skin wounds.

A systematic study of nano-based fibrous systems: Diagnostic and therapeutic approaches for dementia control.

Nano-based systems provide many advantages, including eluding gastrointestinal and first-pass metabolism of the drug and improving the potential advantage of reduced doses of drugs for an equal or better therapeutic effect compared to other parts of oral administration. Over the last few years, protein-based nanofibrous biomaterials have been used for better controlling dementia. PubMed, Scopus, and ISI Web of Science were consulted for available articles on nano-based fibrous systems for the treatment and diagnosis of dementia (up to October 2022). Of 725 articles that were identified and evaluated, only 19 were included. Eleven studies evaluated nanofibrous electrospun biomaterials for better dementia control. Among these, four investigated marker/biomarker detection for the early diagnosis of dementia. Two from four studies conducted hydrogel-based nanofibrous for Alzheimer's disease (AD) treatment. Additionally, four studies inspected stem cell (SC) transplantation on nano-based fibrous scaffolds for better treatment of dementia. Finally, two from the final four studies considered nano-based fibrous systems for the enhanced treatment of dementia. Our study concluded that nano-based fibrous platforms, exclusively peptide/protein-based nanofibrous scaffolds made from biomaterials, can be applied for dementia management by either diagnostic or therapeutic approaches specific in purpose-designed electrospun nanofibrous scaffolds.

Wound healing promotion by flaxseed extract-loaded polyvinyl alcohol/chitosan nanofibrous scaffolds.

Impaired wound healing is a severe complication of sufferers, related to prolonged wound closure, a high infection rate, and eventually disabilities of organs. To aid resolve this issue, we developed the electrospun polyvinyl alcohol and chitosan (PVA/CS) nanofibrous scaffold-loaded flaxseed extract. The scaffold containing 10 wt% of the extract indicated a three-dimensional cross-network with a nano-scale diameter (257 ± 37 nm) and smooth surface. Also, the relevant analyses confirmed high water absorption, porosity, and wettability of the scaffold. Fourier-transform infrared (FTIR), degradation, and mechanical studies revealed the intact presence and loading of the extract into the scaffold, the complete degradation over 48 h, and a high tensile elastic modulus. Besides, the advanced scaffold displayed remarkable anti-oxidant and could inhibit the growth of both Gram-positive and negative bacteria compared to the free PVA/CS scaffold. Desired fibroblast viability and blood compatibility of flaxseed-loaded scaffold endorsed the biocompatibility for wound zones. The in vitro studies showed that the flaxseed-loaded scaffold resulted in an accelerated wound healing process and 100 % closure of the scratched area within 48 h. The results obtained reveal that the flaxseed-loaded PVA/CS electrospun scaffold could be effectively applied for wound healing promotion.

Investigating acetazolamide effectiveness on CSF leak in adul patients after spinal surgery / Investigación de la eficacia de la acetazolamida en la fuga de LCR en pacientes adultos después de una cirugía de column

Introduction and objectives Despite the use of acetazolamide in the management of CSF leak in most patients after CNS surgeries, there is scant evidence in the literature about the efficacy of this established protocol among adult patients in post-spinal surgery observations. We investigated the potential positive effect of acetazolamide in reducing CSF leak after spine surgery. Materials and methods We conducted a single-center, double-blind, randomized-controlled trial comparing Oral Acetazolamide plus Corrected body (prone) position (CP+A) versus Corrected body (prone) position alone(CP−A) from January 2014 to September 2015 in the Neurosurgery ward of Shariati Teaching Hospital, Tehran University of Medical Sciences, Tehran, Iran. Seventy-two Patients divided into two groups [CP−A group (n=36, 50%) and CP+A group (n=36, 50%)] were randomly assigned to this Clinical Trial study. CP+A group (maintained the 3/4 lateral position+dose of acetazolamide 20mg/kg/day in 3–4 divided doses for 7 days), and CP−A group (Control group) (maintained the 3/4 lateral position for 7 days with no acetazolamide). Results Baseline characteristics between the two groups showed no significant differences: Sex (P<0.637), Age (P<0.988) and previous CNS operation at other location besides the spine (P<0.496). Although we reported post-surgical CSF leak in 2/36 (5.55%) of CP+A group and 4/36(11.11%) of CP−A (control) group, there was no significant difference observed between the two groups (95%CI, 0.081–2.748; OR=0.471; P<0.402; Adjusted P<0.247). Additionally, no significant differences were observed when we examined surgical characteristics, such as the size of the dural opening (P<0.489) and type of operation (P<0.465). Conclusion Acetazolamide has no positive effect in controlling CSF leak after dural ... (AU)

Introducción y objetivos A pesar del uso de acetazolamida en el manejo de la fuga de LCR en la mayoría de los pacientes después de cirugías del SNC, existe escasa evidencia en la literatura sobre la eficacia de este protocolo establecido entre pacientes adultos en observaciones poscirugía de columna. Investigamos el posible efecto positivo de la acetazolamida en la reducción de la fuga de LCR después de la cirugía de columna. Materiales y métodos Realizamos un ensayo controlado aleatorio, doble ciego, de un solo centro comparando acetazolamida oral más posición corporal (prona) corregida (CP + A) versus posición corporal (prona) corregida sola (CP-A) desde enero de 2014 hasta septiembre de 2015 en la sala de neurocirugía del Hospital Docente Shariati, Universidad de Ciencias Médicas de Teherán, Teherán, Irán. Setenta y dos pacientes divididos en dos grupos [grupo CP-A (n = 36, 50%) y grupo CP + A (n = 36, 50%)] fueron asignados aleatoriamente a este ensayo clínico. Grupo CP + A (mantuvo la posición lateral 3/4 + dosis de acetazolamida 20mg/kg/día en 3-4 dosis divididas durante 7 días) y grupo CP-A (grupo Control) (mantuvo la posición lateral 3/4 durante 7 días). 7 días sin acetazolamida). Resultados Las características basales entre los dos grupos no mostraron diferencias significativas: sexo (P <0,637), edad (P <0,988) y operación previa del SNC en otra ubicación además de la columna (P <0,496). Aunque informamos fuga de LCR posquirúrgica en 2/36 (5,55%) del grupo CP + A y 4/36 (11,11%) del grupo CP-A (control), no se observaron diferencias significativas entre los dos grupos (95% IC, 0,081-2,748; OR = 0,471; P <0,402; P ajustado <0,247). Además, no se observaron diferencias significativas cuando examinamos las características quirúrgicas, como el tamaño de la abertura dural (P <0,489) y el tipo de operación (P <0,465). Conclusión La acetazolamida no tiene un efecto positivo... (AU)

Tryptophan and serotonin levels as potent biomarkers in diabetes mellitus complications: a new approach of diagnostic role.

Objective: Alterations in the serotonergic system were verified to act a role in the pathogenesis of altered neurological and psychiatric diseases. In recent years, Tryptophan (Trp) and serotonin (5-HT) levels have been considered potent biomarkers of diabetes mellitus (DM). Method: The different Trp metabolism may also play roles in the pathogenesis of DM and mounting risk of complications. The whole blood (WB) 5-HT level was mainly lower among diabetic patients compared to others. That is mostly derived from a lower platelet concentration of 5-HT in these patients. Results: Indeed, 5-HT level can be considered a potent biomarker for early detection of DM complications. Besides, it was proved that outside the digestive and central nervous systems, 5-HT was discovered in beta cells, and scientists have been attempting to realize its mechanism of action ever since. Towards to end, the determination methods, biomarker's role, and approaches of 5-HT and Trp levels were thoroughly investigated in both healthy and diabetic patients with or without complications. Moreover, the association between insulin and 5-HT has been specifically discussed. Conclusions: Our study concluded that Trp and 5-HT levels could be exclusively applied for early diagnosis of DM complications as well as many other complications.

Investigating acetazolamide effectiveness on CSF leak in adult patients after spinal surgery.

INTRODUCTION AND OBJECTIVES: Despite the use of acetazolamide in the management of CSF leak in most patients after CNS surgeries, there is scant evidence in the literature about the efficacy of this established protocol among adult patients in post-spinal surgery observations. We investigated the potential positive effect of acetazolamide in reducing CSF leak after spine surgery. MATERIALS AND METHODS: We conducted a single-center, double-blind, randomized -controlled trial comparing Oral Acetazolamide plus Corrected body (prone) position (CP+A) versus Corrected body (prone) position alone (CP-A) from January 2014 to September 2015 in the Neurosurgery ward of Shariati Teaching Hospital, Tehran University of Medical Sciences, Tehran, Iran. Seventy-two Patients divided into two groups [CP-A group (n = 36, 50%) and CP+A group (n = 36, 50%)] were randomly assigned to this Clinical Trial study. CP+A group (maintained the 3/4 lateral position + dose of acetazolamide 20 mg/kg/day in 3-4 divided doses for 7 days), and CP-A group (Control group) (maintained the 3/4 lateral position for 7 days with no acetazolamide). RESULTS: Baseline characteristics between the two groups showed no significant differences: Sex (P < .637), Age (P < .988) and previous CNS operation at other location besides the spine (P < .496). Although we reported post-surgical CSF leak in 2/36 (5.55%) of CP+A group and 4/36 (11.11%) of CP-A (control) group, there was no significant difference observed between the two groups (95%CI, 0.081-2.748; OR = 0.471; P < .402; Adjusted P < .247). Additionally, no significant differences were observed when we examined surgical characteristics, such as the size of the dural opening (P < .489) and type of operation (P < .465). CONCLUSION: Acetazolamide has no positive effect in controlling CSF leak after dural opening/dural tear in adult patients who undergo spinal surgery, when we considered alongside the one-week prone position. Therefore, acetazolamide administration may not be essential for postoperative spinal surgery for dural tear. Prospective studies involving a larger sample size may be needed to track long-term acetazolamide complications on patients with CSF leak.

Random and Positional Immobilization of Multi-enzyme Systems.

In recent years, three key techniques including random co-immobilization, positional co-immobilization, and compartmentalization for multi-enzyme immobilization were extensively considered. Herein, we investigate random co-immobilization and positional co-immobilization techniques for multi-enzyme systems in detail. We describe randomly co-immobilized glucose oxidase (GOx) and horseradish peroxidase (HRP) on reduced graphene oxide (rGO) as the most used methods. Materials and methods are presented in terms of preparation of GO and rGO as well as enzyme immobilization procedure. Moreover, the principles of positional co-immobilization have been reviewed, and the relevant methods based on microfluidic systems and DNA structure considering HRP and GOx enzymes have been individually studied. It is believed that the benefits of using the methods associated with random and specifically positional immobilized multi-enzyme systems include not only enhanced cascade enzymatic activity via manipulated surface such as microfluidic systems (including porous materials) and DNA structure but also improved enzyme stability and ease of recovery for recycle.

Compartmentalized Immobilization of Multi-enzyme Systems.

The methods of compartmentalized immobilization in multi-enzyme systems containing inorganic complexes and organic scaffolds (i.e. nucleic acid (RNA and DNA), protein and lipid) have been thoroughly investigated. Compartmentalization mostly focuses on dividing individual enzyme(s) into specific location or orientation of the enzymes cooperating in cascade reaction. Organic scaffolds are preferred because of their capability for simultaneous synthesis in biological systems. Besides, the most required methods of horseradish peroxidase (HRP) and glucose oxidase (GOD) enzymes including enzyme activity measurement, enzyme immobilization, removal, and re-hybridization, and enzyme attaching have been provided because they have been extensively applied in multi-enzyme systems. Organic scaffolds have a wide range and properties. Therefore, two methods including dockerin-cohesin linker and nucleotides interaction have been demonstrated for immobilization of enzyme on protein and DNA scaffold, respectively.

Three-layered PCL-collagen nanofibers containing melilotus officinalis extract for diabetic ulcer healing in a rat model.

Active wound dressing with physicochemical and biological characteristics is more effective in healing diabetic foot ulcer (DFU). In this study, a 3-layer electrospun nanofiber wound dressings was fabricated, while its outer, middle and inner layers of the scaffold were made of PCL, PCL/collagen and collagen nanofibers, respectively. Various amounts of Melilotus officinalis extract were also loaded in the collagen nanofibers as a biologically active compound. The diameter and morphology of the obtained nanofibers were investigated by scanning electron microscopy (SEM) and FT-IR spectroscopy to analyse the composition of prepared dressings. The efficacy of the fabricated dressings as wound healing agent was assessed in streptozotocin-induced diabetic rats. The results demonstrated that the mean diameter of nanofibers are 373 ± 179 nm, 266 ± 108 nm, 160 ± 52 nm, and 393 ± 131 nm for PCL, PCL/collagen, pure collagen, and collagen nanofibers containing 0.08 g extract, respectively. The histo-pathology and histomorphometry assessments demonstrate the herbal extract-loaded electrospun dressings (especially containing 0.08 g of the extract) are promising in improving the diabetic ulcer healing. Our results indicated that the combination of drug did not compromise the physicochemical characteristics of wound dressing, while improving its biological activities.

Interactive relationship between Trp metabolites and gut microbiota: The impact on human pathology of disease.

Tryptophan (Trp), an α-amino acid, is the precursor of serotonin (5-hydroxytryptamine, 5-HT), which is involved in a variety of features of metabolic function and human nutrition. Evidence highlights the role of Trp metabolites (exclusively 5-HT) in the gastrointestinal (GI) tract; however, the mechanisms of action involved in the release of 5-HT in the GI tract are still unknown. Considering the fact that variations of 5-HT may facilitate the growth of certain GI disorders, gaining a better understanding of the function and release of 5-HT in the GI tract would be beneficial. Additionally, investigating Trp metabolism may clarify the relationship between Trp and gut microbiota. It is believed that other metabolites of Trp (mostly that of the kynurenine pathway) may play a significant role in controlling gut microbiota function. In this review, we have attempted to summarize the current research investigating the relationship of gut microbiota, Trp and 5-HT metabolism (with particular attention paid to their metabolite type, as well as a discussion of the research methods used in each study). Taking together, regarding the role that Trp/5-HT plays in a range of physical and mental diseases, the gut bacterial types, as well as the related disorders, have been exclusively considered.

Nanofiber-based systems intended for diabetes.

Diabetic mellitus (DM) is the most communal metabolic disease resulting from a defect in insulin secretion, causing hyperglycemia by promoting the progressive destruction of pancreatic ß cells. This autoimmune disease causes many severe disorders leading to organ failure, lower extremity amputations, and ultimately death. Modern delivery systems e.g., nanofiber (NF)-based systems fabricated by natural and synthetic or both materials to deliver therapeutics agents and cells, could be the harbinger of a new era to obviate DM complications. Such delivery systems can effectively deliver macromolecules (insulin) and small molecules. Besides, NF scaffolds can provide an ideal microenvironment to cell therapy for pancreatic ß cell transplantation and pancreatic tissue engineering. Numerous studies indicated the potential usage of therapeutics/cells-incorporated NF mats to proliferate/regenerate/remodeling the structural and functional properties of diabetic skin ulcers. Thus, we intended to discuss the aforementioned features of the NF system for DM complications in detail.

Nanobiocide Based-Silver Nanomaterials Upon Coronaviruses: Approaches for Preventing Viral Infections.

The effectiveness of silver nanomaterials (AgNMs), as antiviral agents, has been confirmed in humans against many different types of viruses. Nanobiocides-based AgNMs can be effectively applied to eliminate coronaviruses (CoVs), as the cause of various diseases in animals and humans, particularly the fatal human respiratory infections. Mostly, these NMs act effectively against CoVs, thanks to the NMs' fundamental anti-viral structures like reactive oxygen species (ROS), and photo-dynamic and photo-thermal abilities. Particularly, the antiviral activity of AgNMs is clarified under three inhibitory mechanisms including viral entry limitation, attachment inhibition, and viral replication limitation. It is believed that nanobiocide with other possible materials such as TiO2, silica and, carbon NMs exclusively nano-graphene materials can emerge as a more effective disinfectant for long-term stability with low toxicity than common disinfectants. Nanobiocides also can be applied for the prevention and treatment of viral infections specifically against COVID-19.

Serotonin level as a potent diabetes biomarker based on electrochemical sensing: a new approach in a zebra fish model.

Serotonin (5-HT) levels have been associated with several exclusively metabolic disorders. Herein, a new approach for 5-HT level as a novel biomarker of diabetes mellitus is considered using a simple nanocomposite and HPLC method. Reduced graphene oxide (rGO) comprising gold nanoparticles (AuNPs) was decorated with 18-crown-6 (18.Cr.6) to fabricate a simple nanocomposite (rGO-AuNPs-18.Cr.6). The nanocomposite was positioned on a glassy carbon electrode (GCE) to form an electrochemical sensor for the biomarker 5-HT in the presence of L-tryptophan (L-Trp), dopamine (DA), ascorbic acid (AA), urea, and glucose. The nanocomposite exhibited efficient catalytic activity for 5-HT detection by square-wave voltammetry (SWV). The proposed sensor displayed high selectivity, excellent reproducibility, notable anti-interference ability, and long-term stability even after 2 months. SWV defined a linear range of 5-HT concentration from 0.4 to 10 µg L-1. A diabetic animal model (diabetic zebrafish model) was then applied to investigate 5-HT as a novel biomarker of diabetes. A limit of detection (LOD) of about 0.33 µg L-1 was found for the diabetic group and 0.15 µg L-1 for the control group. The average levels of 5-HT obtained were 9 and 2 µg L-1 for control and diabetic groups, respectively. The recovery, relative standard deviation (RSD), and relative error (RE) were found to be about 97%, less than 2%, and around 3%, respectively. The significant reduction in 5-HT level in the diabetic group compared to the control group proved that the biomarker 5-HT can be applied for the early diagnosis of diabetes mellitus.

Effective antibacterial electrospun cellulose acetate nanofibrous patches containing chitosan/erythromycin nanoparticles.

Herein, we fabricated the antibacterial nanofibrous mats composed of cellulose acetate (CA) nanofibers loaded with erythromycin-chitosan nanoparticles (Ery-CS NPs) intended for infected wound dressing. The Ery-loaded CS NPs were prepared by ionic gelation process and then incorporated into the CA electrospun nanofibers (NFs). Regarding physiochemical properties, the NPs and obtained mats were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), attenuated total reflection fourier transform infrared (ATR-FTIR), and contact angle measurement. The antimicrobial activity and cell viability of fibroblast cells were also evaluated. The results indicated that Ery was loaded into CS NPs with high encapsulation efficiency (95%). The CA NFs (17% w/v) incorporated with the Ery-CS NPs (12 wt%) displayed smooth homogenous morphology with 141.7 ± 91.7 nm average diameter. The relevant analyses confirmed that the NPs incorporated into NFs and provided high water holding capacity with high porosity. Finally, Ery-CS NPs/CA mats were able to inhibit the growth of both Gram-positive and Gram-negative bacteria as well as showed no cytotoxic effect on the human dermal fibroblast cells. Overall, our findings concluded that the proposed system could be potentially applied as the proper antibacterial mats for infected wound dressing applications.

Immobilization of Cellulase onto Core-Shell Magnetic Gold Nanoparticles Functionalized by Aspartic Acid and Determination of its Activity.

New support was fabricated to enhance the enzyme activity of cellulase following immobilization. Functionalized core-shell magnetic gold nanoparticles were prepared and characterized by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cellulase enzyme was immobilized on support via covalent bonding. The successful binding of the enzyme was chemically confirmed by Fourier-transform infrared spectroscopy (FTIR). The binding efficiency was 84% determined by Bradford assay. Filter Paper Activity (FPase) method was used to measure the enzyme activity at different temperatures (35-75 °C) and pH (2-8). The immobilized cellulase maintained 73% of its initial catalytic activity after 9 h and its activity is 0.78 mmol.ml-1. The newly designed nano-system also enhanced the thermal stability of immobilized cellulase in comparison to free cellulase and facilitated its long term storage.