Effect of Lavandula angustifolia and Cananga odorata on decrease of blood pressure in high blood pressure volunteers: A randomized controlled trial.

INTRODUCTION: Hypertension is one of the most dangerous diseases. However, medicine for hypertension may cause adverse effects. Thus, alternative treatments may be beneficial to patients. The aims of the study were to evaluate efficacy and safety of sticker pads containing lavender and ylang ylang oil (LY pads) on decrease blood pressure. MATERIALS AND METHODS: The LY pads had been developed since 2018. The safety of LY pads in healthy volunteers' study and the efficacy and safety of LY pads in high blood pressure volunteers' study were conducted at Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand in October 2020 to December 2022. In the safety of LY pads in healthy volunteers' study, the LY pad was attached to the shirts of 56 healthy volunteers for 2 h. Adverse reactions, irritation score, and quality of life were assessed. In the efficacy and safety of the LY pads in high blood pressure volunteers' study, 34 high blood pressure volunteers were randomly divided into the LY group or the placebo group. The volunteers attached the pad to their shirt for 14 days. Blood pressure, pulse rate, and adverse reactions were investigated. RESULTS: The LY pad was safe for humans. Using the LY pad for 2 h had no significant adverse reactions in healthy volunteers. Moreover, it significantly improved quality of life (p<0.05). The blood pressure of the LY pad group after at least 3 days use was significantly lower than before using the pad (p<0.05). The systolic blood pressure difference and pulse rate difference were also superior in the LY pad group compared to the placebo group (p<0.05). CONCLUSIONS: The LY pad was safe in healthy volunteers and could reduce blood pressure in high blood pressure volunteers without adverse effects. Thus, it may be a supportive or alternative treatment for hypertension.

Using polyvinyl alcohol-ionic hydrogels containing a wound healing agent to manage wounds in different environments.

OBJECTIVE: To explore the effects of pH on properties of polyvinyl alcohol (PVA)-ionic hydrogels containing wound healing promoters. METHOD: PVA was combined with a natural wound healing promoter (silk sericin (SS)), and an anionic agent (eosin (ES)) or cationic agent (methylene blue (MB)), and made into hydrogels. Properties of the hydrogels and behaviour at different pHs were investigated. RESULTS: The density and gel fraction of PVA/SS-ES hydrogel and PVA/SS-MB hydrogel were considerably lower compared with hydrogel without SS. The swelling ratio and degradation of the hydrogels increased with increasing SS concentration in all pH solutions. The influence of SS in interrupting long-chain PVA molecules was confirmed based on changes in Fourier-transform infrared spectroscopy (FTIR). The SS released from the gels was found to interact with the ionic agent and influenced the release profile of the ionic agent. Surprisingly, the anionic agent in PVA/SS-ES hydrogel showed 70% release in high pH solution whereas the cationic agent in PVA/SS-MB hydrogel showed 86% release in low pH solution. Moreover, the active agent could accumulate on the skin layer and had a positive effect on a specific wound area. CONCLUSION: Based on the results obtained in this study, it is suggested to use anionic hydrogels containing wound healing promoter for wounds at high pH and cationic hydrogels containing wound healing promoter for wounds with low pH. Ability to improve wound healing using a natural healing agent combined with ionic agents and controlling the pH of hydrogels will help in developing quick and low-cost treatment for wounds.

Evaluating efficacy and safety of the topical silicone gel containing onion extract in the treatment of post-cesarean surgical scars.

BACKGROUND: Cesarean section scars are post-surgical problems in women. Many active ingredients have been found to diminish scar formation. Clinical investigations on the onion extract have gained more attention due to its properties, such as improvement of scar appearance and texture. However, published studies evaluating the usefulness of the onion extract in the treatment of scars are controversial. METHODS: The three-month study period followed a prospective, randomized, and double-blinded design. Each enrolled subject's post-cesarean completely sealed wounds were divided into two halves along the closure axis. Each half was randomly assigned to the treatment with either silicone gel containing 5% onion extract or the silicone gel containing vitamin C. All subjects were respectively evaluated at the one, two, and three months of the treatment. RESULTS: After the three-month follow-up, there was a statistically significant difference in scar improvement between before and after treatment. None of statistically significant difference in the Patient and Observer Scar Assessment Scale (POSAS) and Vancouver Scar Scale (VSS) scores and melanin value was found between silicone gel containing 5% onion extract and the control silicone gel. However, the improvement of scar erythema by treatment with the silicone gel containing 5% onion extract was significantly greater than in the control group. No adverse effects were reported in either group.

Superior Technique for the Production of Agarose Dressing Containing Sericin and Its Wound Healing Property.

Finding a simple and eco-friendly production technique that matches to the natural agent and results in a truly valuable natural scaffold production is still limited amongst the intensively competitive natural scaffold development. Therefore, the purpose of this study was to develop natural scaffolds that were environmentally friendly, low cost, and easily produced, using natural agents and a physical crosslinking technique. These scaffolds were prepared from agarose and sericin using the freeze-drying method (D) or freeze-thawing together with the freeze-drying method (TD). Moreover, plasticizers were added into the scaffold to improve their properties. Their physical, mechanical, and biological properties were investigated. The results showed that scaffolds that were prepared using the TD method had stronger bonding between sericin and other compounds, leading to a low swelling ratio and low protein release of the scaffolds. This property may be applied in the development of further material as a controlled drug release scaffold. Adding plasticizers, especially glycerin, into the scaffolds significantly increased elongation properties, leading to an increase in elasticity of the scaffold. Moreover, all scaffolds could activate cell migration, which had an advantage on wound healing acceleration. Accordingly, this study was successful in developing natural scaffolds using natural agents and simple and green crosslinking methods.

Fibroin and Polyvinyl Alcohol Hydrogel Wound Dressing Containing Silk Sericin Prepared Using High-Pressure Carbon Dioxide.

Objective: To fabricate and investigate the properties of fibroin and polyvinyl alcohol (PVA) hydrogels containing sericin prepared using high-pressure carbon dioxide (CO2). Approach: In this study, fibroin/PVA hydrogels with and without sericin were prepared using the high-pressure CO2 method. The physical and mechanical properties of the hydrogels were investigated using field-emission scanning electron microscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry, and the swelling, water retention, and compressive properties were assessed. Results: The hydrogels obtained from the combination of fibroin and PVA presented a compositional gradient along the hydrogel thickness and structure. The upper layer of the hydrogel consisted of a fibroin-based hydrogel blended with PVA, whereas the lower layer contained only fibroin. The mechanical properties regarding compression of the fibroin/PVA hydrogel were significantly better than those of the pure fibroin hydrogel, for hydrogels with and without sericin. Moreover, the mechanical properties of the hydrogels with sericin were significantly better than those without sericin. The water contents of all samples were >90%. Innovation: This study assessed a new combination of a wound healing agent and a biomaterial dressing. Moreover, this hydrogel production technique used a clean method without the need for a chemical crosslinking agent. Conclusion: The combination of the fibroin and PVA hydrogel and sericin prepared using the high-pressure CO2 method led to good physical properties. This material may be a candidate for medical applications.

The downside of antimicrobial agents for wound healing.

The use of topical antimicrobials is beneficial for infection control in wound care because wound infection is the major cause of delayed healing. The advantages of topical over systemic antimicrobials include a higher concentration at the target site, fewer systemic adverse effects, and a lower incidence of antimicrobial resistance. Nowadays, topical antimicrobials are divided into three groups: disinfectants, antiseptics, and antibiotics. Only antiseptics and antibiotics can be applied to living skin; therefore, this review will focus only on these groups. The advantages of each topical antimicrobial are well established; however, their disadvantages remain prominent. It is widely known that antiseptics show higher cytotoxicity and a broader spectrum of activity than antibiotics, whereas antibiotics show a higher probability of bacterial resistance development. However, there are still many adverse effects, resulting from each topical antimicrobial. This review aims to summarize the possible adverse effects of commonly used antiseptics (biguanide, silver, iodine, chlorine compounds, and other antiseptics), antibiotics (bacitracin, mafenide, mupirocin, neomycin, and silver sulfadiazine), and natural antimicrobials (curcumin and honey). Moreover, the antimicrobials that should be avoided in particular populations are also summarized in this review in order to increase awareness for antimicrobial selection in those populations.

Inflammatory reaction, clinical efficacy, and safety of bacterial cellulose wound dressing containing silk sericin and polyhexamethylene biguanide for wound treatment.

Bacterial cellulose wound dressings containing silk sericin and PHMB (BCSP) were developed in our previous studies. It had good physical properties, efficacy, and safety. For further use as a medical material, this dressing was investigated for its efficacy and safety in split-thickness skin graft (STSG) donor-site wound treatment compared to Bactigras® (control). Moreover, the inflammatory responses to both dressings were also deeply investigated. For in vivo study, expressions of anti-inflammatory cytokines were intensely considered in the tissue interfacing area. The result showed that IL-4 and TGF-ß from BCSP-treated tissue had advantages over Bactigras®-treated tissue at 14 and 21 days post-implantation. For clinical study, a single-blinded, randomized controlled study was generated. The half of STSG donor site wound was randomly assigned to cover with BCSP or Bactigras®. Twenty-one patients with 32 STSG donor site wounds were enrolled. The results showed that wound-healing time was not significantly different in both dressings. However, wound quality of BCSP was better than Bactigras® at healing time and after 1 month (p < 0.05). The pain scores of BCSP-treated wound were statistically significant lower than Bactigras®-treated wound (p < 0.05). No sign of infection or adverse event was observed after treatment with both dressings. In conclusion, the inflammation responses of the dressing were clearly clarified. The advantages of BCSP were wound-quality improvement, pain reduction, and infection protection without adverse events. It was fit to be used as the alternative treatment of STSG donor site wound.

Identification and quantification and antioxidant activity of flavonoids in different strains of silk cocoon, Bombyx mori.

Silk cocoon is produced from silkworm (Bombyx mori) to protect itself from outer environment. Various strains of cocoon contain different forms and amounts of flavonoids, which may affect on their antioxidant activity. Moreover, the extraction method would influence the amount of flavonoids extracted. Therefore, the objectives of this study were to identify and quantify the flavonoids in 3 strains of bivoltine Bombyx mori silk cocoon (Chul 1/1; white cocoon, Chul 3/2; greenish cocoon, and Chul 4/2; yellow cocoon) extracted by 6 different solvents including acetone, ethyl acetate, dimethyl sulfoxide (DMSO), ethanol, methanol, and purified water. The flavonoids extracted were identified and quantified by liquid chromatography-mass spectrometry (LC-MS). The antioxidant activity of flavonoids extracted was also investigated by visible spectroscopy at 517 nm. The results showed that Chul 3/2 silk cocoon contained the highest amount of flavonoids. Purified water seemed to be the best solvent that preserved most antioxidant activity of the flavonoids extracted. Flavonoids in Chul 1/1 and Chul 4/2 silk cocoon were rarely found, however they contained some antioxidant activities. The data from this study can provide basic information for flavonoid extraction from silk cocoon which can also apply for other flavonoid-containing natural biomaterials.

Effect of animal products and extracts on wound healing promotion in topical applications: a review.

Wound healing is a natural process of body reaction to repair itself after injury. Nonetheless, many internal and external factors such as aging, comorbidity, stress, smoking, alcohol drinking, infections, malnutrition, or wound environment significantly affect the quality and speed of wound healing. The unsuitable conditions may delay wound healing process and cause chronic wound or scar formation. Therefore, many researches have attempted to search for agents that can accelerate wound healing with safety and biocompatibility to human body. Widely studied wound healing agents are those derived from either natural sources including plants and animals or chemical synthesis. The natural products seem to be safer and more biocompatible to human tissue. This review paper demonstrated various kinds of the animal-derived products including chitosan, collagen, honey, anabolic steroids, silk sericin, peptides, and proteoglycan in term of mechanisms of action, advantages, and disadvantages when applied as wound healing accelerator. The benefits of these animal-derived products are wound healing promotion, anti-inflammatory, antimicrobial activity, moisturizing effect, biocompatibility, and safety. However, the drawbacks such as allergy, low stability, batch-to-batch variability, and high extraction and purification costs could not be avoided in some products.

The safety and efficacy of bacterial nanocellulose wound dressing incorporating sericin and polyhexamethylene biguanide: in vitro, in vivo and clinical studies.

In our previous work, we have attempted to develop a novel bacterial nanocellulose wound dressing which composed of both polyhexamethylene biguanide (PHMB) as an antimicrobial agent and sericin as an accelerative wound healing component. The loading sequence and concentration of PHMB and sericin were optimized to provide the wound dressing with the most effective antimicrobial activity and enhanced collagen production. In this study, further in vitro, in vivo, and clinical studies of this novel wound dressing were performed to evaluate its safety, efficacy, and applicability. For the in vitro cytotoxic test with L929 mouse fibroblast cells, our novel dressing was not toxic to the cells and also promoted cell migration as good as the commercially available dressing, possibly due to the component of sericin released. When implanted subcutaneously in rats, the lower inflammation response was observed for the novel dressing implanted, comparing to the commercially available dressing. This might be that the antimicrobial PHMB component of the novel dressing played a role to reduce infection and inflammation reaction. The clinical trial patch test was performed on the normal skin of healthy volunteers to evaluate the irritation effect of the dressing. Our novel dressing did not irritate the skin of any volunteers, as characterized by the normal levels of erythema and melanin and the absence of edema, papule, vesicle, and bullae. Then, the novel dressing was applied for the treatment of full-thickness wounds in rats. The wounds treated with our novel dressing showed significantly lower percentage of wound size and higher extent of collagen formation mainly due to the activity of sericin. We concluded that our novel bacterial nanocellulose incorporating PHMB and sericin was a safe and efficient wound dressing material for further investigation in the wound healing efficacy in clinic.

Interaction and effectiveness of antimicrobials along with healing-promoting agents in a novel biocellulose wound dressing.

An ideal wound dressing should keep the wound moist, allow oxygen permeation, adsorb wound exudate, accelerate re-epithelialization for wound closure, reduce pain and healing time, and prevent infection. Our novel biocellulose-based wound dressing was composed of three components: 1) biocellulose (BC), intended to create a moist and oxygen-permeated environment with exudate adsorption; 2) silk sericin (SS) known for its enhancement of collagen type I production, which is critical for re-epithelialization; and 3) the antiseptic polyhexamethylene biguanide (PHMB). To deliver an effective BC wound dressing, the interactions between the components (PHMB vs. SS) needed to be thoroughly analyzed. In this study, we investigated important parameters such as the loading sequence, loading concentration, and loading amount of the active compounds to ensure that the BC wound dressing could provide both antimicrobial activity and promote collagen production during healing. The loading sequence of SS and PHMB into BC was critical to maintain PHMB antimicrobial activity; silk sericin needed to be loaded before PHMB to avoid any negative impacts. The minimum PHMB concentration was 0.3% w/v for effective elimination of all tested bacteria (Bacillus subtilis, Staphylococcus aureus, methicillin-resistant S. aureus, Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa). The amounts of SS and PHMB in BC were optimized to ensure that the dressings released the optimal amounts of both SS to enhance fibroblast collagen production and PHMB for effective antimicrobial activity.