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1.
Medicina (Kaunas) ; 58(6)2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35744098

RESUMEN

Background and Objectives: Wound healing is commonly associated with critical bacterial colonization or bacterial infection, which induces prolonged inflammation, resulting in delayed re-epithelialization. An appropriate wound dressing requires a humid environment, which also functions as a barrier against bacterial contamination and will accelerate a regenerative response of the wound. Silver sulfadiazine (SSD) is used to prevent wound infection. Hyaluronic acid (HA) is an extracellular matrix component involved in tissue regeneration. This retrospective study was conducted to evaluate the effectiveness of cream and gauze pads based on hyaluronic acid at low molecular weight (200 kDa) and silver sulfadiazine 1% in the wound healing process. In addition, we examined SSD action on biofilms in vitro and on animal wounds, obtaining positive outcomes therefrom. Materials and Methods: We selected 80 patients with complicated chronic wounds of different etiologies, including diabetes mellitus (10), post-traumatic ulcers (45), burns (15), and superficial abrasion (10). Results: After 8 weeks, ulcer size was decreased in 95 ± 2% of the treated patients; a significant reduction in the inflammatory process was observed from day 14 onwards (p < 0.01 vs. baseline), considering improvement of the surrounding skin and reduction of the bacterial load. The SSD treatment decreased bacterial colony proliferation, both in planktonic state and in biofilm, in a dose-dependent manner on the wound but inhibited the development of tissue granulation at the highest dose (800 µg/wound). Conclusions: In conclusion, the combined action of SSD and HA is clinically effective in improving wound healing.


Asunto(s)
Ácido Hialurónico , Sulfadiazina de Plata , Animales , Biopelículas , Humanos , Ácido Hialurónico/farmacología , Ácido Hialurónico/uso terapéutico , Estudios Retrospectivos , Sulfadiazina de Plata/farmacología , Sulfadiazina de Plata/uso terapéutico , Cicatrización de Heridas
2.
Medicina (Kaunas) ; 56(7)2020 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-32610512

RESUMEN

Background and objectives: Skin grafting is a method usually used in reconstructive surgery to accelerate skin regeneration. This method results frequently in unexpected scar formations. We previously showed that cutaneous wound-healing in normal mice is accelerated by a micrograft (MG) technique. Presently, clinical trials have been performed utilizing this technology; however, the driving mechanisms behind the beneficial effects of this approach remain unclear. In the present study, we focused on five major tissue reactions in wound-healing, namely, regeneration, migration, granulation, neovascularization and contraction. Methods: Morphometrical analysis was performed using tissue samples from the dorsal wounds of mice. Granulation tissue formation, neovascularization and epithelial healing were examined. Results: The wound area correlated well with granulation sizes and neovascularization densities in the granulation tissue. Vascular distribution analysis in the granulation tissue indicated that neovessels extended and reached the subepidermal area in the MG group but was only halfway developed in the control group. Moreover, epithelialization with regeneration and migration was augmented by MG. Myofibroblast is a known machinery for wound contraction that uses α-smooth muscle actin filaments. Their distribution in the granulation tissue was primarily found beneath the regenerated epithelium and was significantly progressed in the MG group. Conclusions: These findings indicated that MG accelerated a series of wound-healing reactions and could be useful for treating intractable wounds in clinical situations.


Asunto(s)
Suspensiones/uso terapéutico , Trasplante Autólogo/métodos , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología , Actinas/análisis , Animales , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Miofibroblastos/fisiología , Suspensiones/farmacología , Trasplante Autólogo/normas , Cicatrización de Heridas/inmunología
3.
J Cell Physiol ; 232(6): 1225-1232, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27626888

RESUMEN

The mouse excisional dorsal full-thickness wound model with a silicon splint fixed on the skin has been widely used to mimic human wound healing. However, the method cannot accurately quantify dermal remodeling, since the initial point of epithelialization on the wound surface is unclear. To overcome this limitation, we have developed a novel mouse excisional wound model to assess the degree of epithelial extension and regeneration, using a plastic ring-shaped splint fixed beneath the surrounding epidermal tissue. At the end of the experiment, tissue samples were fixed in formalin, the splint was excised, and paraffin sections were prepared. Splint holes, corresponding to the prior location of the splint, were evident on the tissue cross-sections, and the epidermis above the holes was considered the initial excision site. The epidermal contraction and epithelial regeneration, as independent essential tissue alterations in wound healing, could be distinguishable and quantified. Compared with previous splint models, this method provides an accurate evaluation of epidermal processes in wound healing, and can be a platform to assess the effects of various wound healing factors. J. Cell. Physiol. 232: 1225-1232, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Dermis/patología , Repitelización , Férulas (Fijadores) , Animales , Glucemia/metabolismo , Peso Corporal , Hiperglucemia/sangre , Hiperglucemia/complicaciones , Hiperglucemia/patología , Queratina-6/metabolismo , Masculino , Ratones Endogámicos C57BL , Obesidad/sangre , Obesidad/complicaciones , Obesidad/patología , Factores de Tiempo
4.
Int J Mol Sci ; 18(8)2017 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-28767054

RESUMEN

A micrograft technique, which minces tissue into micro-fragments >50 µm, has been recently developed. However, its pathophysiological mechanisms in wound healing are unclear yet. We thus performed a wound healing study using normal mice. A humanized mouse model of a skin wound with a splint was used. After total skin excision, tissue micro-fragments obtained by the Rigenera protocol were infused onto the wounds. In the cell tracing study, GFP-expressing green mice and SCID mice were used. Collagen stains including Picrosirius red (PSR) and immunohistological stains for α-smooth muscle actin (αSMA), CD31, transforming growth factor-ß1 (TGF-ß1) and neutrophils were evaluated for granulation tissue development. GFP-positive cells remained in granulation tissue seven days after infusion, but vanished after 13 days. Following the infusion of the tissue micrograft solution onto the wound, TGF-ß1 expression was transiently upregulated in granulation tissue in the early phase. Subsequently, αSMA-expressing myofibroblasts increased in number in thickened granulation tissue with acceleration of neovascularization and collagen matrix maturation. On such granulation tissue, regenerative epithelial healing progressed, resulting in wound area reduction. Alternative alteration after the micrograft may have increased αSMA-expressing myofibroblasts in granulation tissue, which may act on collagen accumulation, neovascularization and wound contraction. All of these changes are favorable for epithelial regeneration on wound.


Asunto(s)
Matriz Extracelular , Miofibroblastos , Trasplante de Piel , Piel , Cicatrización de Heridas , Animales , Autoinjertos , Rastreo Celular/métodos , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/patología , Ratones , Ratones SCID , Ratones Transgénicos , Miofibroblastos/metabolismo , Miofibroblastos/patología , Piel/lesiones , Piel/metabolismo , Piel/patología
5.
Biomed Chromatogr ; 29(9): 1428-31, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25678451

RESUMEN

Linezolid is an antimicrobial agent for the treatment of multiresistant Gram-positive infections. A practical high-performance liquid chromatography method was developed for the determination of linezolid in human plasma and saliva. Linezolid and an internal standard (o-ethoxybenzamide) were extracted from plasma and saliva with ethyl acetate and analyzed on a Capcell Pak C18 MG column with UV detection at 254 nm. The calibration curve was linear through the range 0.5-50 µg/mL using a 200 µL sample volume. The intra- and interday precisions were all <6.44% for plasma and 5.60% for saliva. The accuracies ranged from 98.8 to 110% for both matrices. The mean recoveries of linezolid were 80.8% for plasma and 79.0% for saliva. This method was used to determine the plasma and saliva concentrations of linezolid in healthy volunteers who were orally administered a 600 mg dose of linezolid. Our liquid-liquid extraction procedure is easy and requires a small volume of plasma or saliva (200 µL). This small volume can be advantageous in clinical pharmacokinetic studies, especially if children participate.


Asunto(s)
Antibacterianos/análisis , Cromatografía Líquida de Alta Presión/métodos , Linezolid/análisis , Saliva/química , Adulto , Antibacterianos/sangre , Humanos , Linezolid/sangre , Masculino , Persona de Mediana Edad
6.
Int Wound J ; 12(2): 122-31, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23506400

RESUMEN

Indwelling foreign-body infections are a critical medical problem, especially in immunocompromised patients. To examine the pathogenicity of biofilm-forming bacteria settling on foreign materials, mice implanted with plastic discs were infected with Staphylococcus aureus. After opening a wide subcutaneous pocket on the dorsal side of mice with or without temporal leukocytopenia, a plastic sheet was placed in the left subcutaneous space; subsequently, bacteria in a planktonic state were dispersed over the subcutaneous space. Bacterial numbers were examined 7 days after inoculation. In subcutaneous tissue on the right, S. aureus was found only in leukocytopenic mice. Meanwhile, bacteria were detected on the plastic and neighbouring tissue in both leukocytopenic and normal mice; however, colony-forming analysis indicated that leukocytopenic mice possessed significantly more bacteria. Tissue reaction against bacteria was pathologically examined. Invading S. aureus induced severe inflammation. In transient leukocytopenic mice, bacterial microcolonies formed on the plastic as well as in the developed necrotic tissue - both of which were shielded from inflammatory cell infiltration - result in bacteraemia. These results indicate that biofilm-forming S. aureus settling on indwelling foreign material are tolerant against host immunity and assault neighbouring tissue, which may lead to chronic wound infection.


Asunto(s)
Biopelículas , Cuerpos Extraños/microbiología , Infecciones Estafilocócicas/etiología , Staphylococcus aureus/fisiología , Infección de Heridas/etiología , Animales , Modelos Animales de Enfermedad , Femenino , Cuerpos Extraños/patología , Leucopenia/complicaciones , Leucopenia/patología , Ratones , Ratones Endogámicos C57BL , Infecciones Estafilocócicas/patología , Infección de Heridas/patología
7.
Biomed Chromatogr ; 27(7): 818-20, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23420764

RESUMEN

A practical high-performance liquid chromatography using a Cosmosil HILIC column and UV detection was developed for determining the concentrations of cytosine arabinoside (Ara-C) and uracil arabinoside (Ara-U), which is a major metabolite of Ara-C, in human plasma. This method was used to determine the plasma concentrations of Ara-C and Ara-U in a patient treated with high-dose Ara-C therapy for end-stage renal failure.


Asunto(s)
Arabinofuranosil Uracilo/sangre , Cromatografía Líquida de Alta Presión/métodos , Citarabina/sangre , Arabinofuranosil Uracilo/química , Citarabina/química , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Límite de Detección , Modelos Lineales , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta
8.
Stem Cells ; 29(10): 1485-95, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21919130

RESUMEN

Cancer stem cells (CSCs) that display tumor-initiating properties have recently been identified. CD133, a surface glycoprotein linked to organ-specific stem cells, has been described as a marker of CSCs in different tumor types. We herein identify and characterize CSCs in human uterine carcinosarcoma (malignant mixed Müllerian tumor), which is one of the most aggressive and therapy-resistant gynecological malignancies and is considered to be of mesodermal origin. The CD133(+) population was increased in uterine carcinosarcoma, and this population showed biphasic properties in the primary tumor. CD133(+) cells predominantly formed spheres in culture and were able to differentiate into mesenchymal lineages. CD133(+) cells were more resistant to cisplatin/paclitaxel-induced cytotoxicity in comparison with CD133(-) cells. A real-time polymerase chain reaction analysis of the genes implicated in stem cell maintenance revealed that CD133(+) cells express significantly higher levels of Oct4, Nanog, Sox2, and Bmi1 than CD133(-) cells. Moreover, CD133(+) cells showed a high expression level of Pax2 and Wnt4, which are genes essential for Müllerian duct formation. These CD133(+) cells form serially transplantable tumors in vivo and the resulting CD133(+) tumors replicated the EpCAM, vimentin, and estrogen and progesterone receptor expression of the parent tumor, indicating that CSCs likely differentiated into cells comprising the uterine carcinosarcoma tissue. Moreover, strong CD133 expression in both epithelial and mesenchymal elements in primary tumor demonstrated significant prognostic value. These findings suggest that CD133(+) cells have the characteristics of CSCs and Müllerian mesenchymal progenitors.


Asunto(s)
Antígenos CD/metabolismo , Carcinosarcoma/patología , Regulación Neoplásica de la Expresión Génica , Glicoproteínas/metabolismo , Células Madre Neoplásicas/patología , Péptidos/metabolismo , Neoplasias Uterinas/patología , Antígeno AC133 , Animales , Antígenos de Neoplasias/metabolismo , Carcinosarcoma/genética , Carcinosarcoma/metabolismo , Moléculas de Adhesión Celular/metabolismo , Diferenciación Celular , Línea Celular Tumoral , Separación Celular/métodos , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Cisplatino/farmacología , Resistencia a Antineoplásicos , Molécula de Adhesión Celular Epitelial , Receptor beta de Estrógeno/metabolismo , Femenino , Citometría de Flujo , Proteínas de Homeodominio/metabolismo , Humanos , Inmunohistoquímica , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Tumor Mulleriano Mixto/metabolismo , Tumor Mulleriano Mixto/patología , Proteína Homeótica Nanog , Células Madre Neoplásicas/citología , Células Madre Neoplásicas/efectos de los fármacos , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Factor de Transcripción PAX2/metabolismo , Paclitaxel/farmacología , Factores de Transcripción SOXB1/metabolismo , Neoplasias Uterinas/genética , Neoplasias Uterinas/metabolismo , Vimentina/metabolismo , Proteína Wnt4/metabolismo
9.
Biomed Chromatogr ; 26(1): 76-80, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21437923

RESUMEN

A simple and sensitive HPLC method has been developed for the determination of methotrexate (MTX) and its major metabolites, 7-hydroxymethotrexate (7-OH-MTX) and 2,4-diamino-N(10-) methylpteroic acid (DAMPA), in human plasma. After deproteinization of the plasma with 5% aqueous acetonitrile solution containing 5% trichloroacetic acid, MTX, 7-OH-MTX, DAMPA and 2,4-diaminopteroic acid (DAPA) as an internal standard were separated on a reversed-phase column, and the eluent was subsequently irradiated with UV light (245 nm), producing fluorescent photolytic degradation products. The analytes were then detected spectrofluorometrically at 452 nm with excitation at 368 nm. The extraction efficiencies of MTX, 7-OH-MTX and DAMPA from plasma at 100 pmol/mL were 81.5±5.4, 82.5±5.3 and 56.2±7.0%, respectively. The limits of quantification for MTX, 7-OH-MTX and DAMPA in plasma were 5 pmol (2.3 ng), 0.8 pmol (0.38 ng) and 10 pmol (3.4 ng)/mL, respectively. The within- and between-day variations for MTX, 7-OH-MTX and DAMPA were reliable (each was lower than 6.3%). This method was also used to monitor the concentrations of MTX and its metabolites in a patient on MTX therapy.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Metotrexato/análogos & derivados , Metotrexato/sangre , Espectrometría de Fluorescencia/métodos , Anciano , Antimetabolitos Antineoplásicos/sangre , Antimetabolitos Antineoplásicos/farmacocinética , Antimetabolitos Antineoplásicos/uso terapéutico , Cromatografía de Fase Inversa , Humanos , Límite de Detección , Modelos Lineales , Linfoma de Células B Grandes Difuso/sangre , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Masculino , Metotrexato/farmacocinética , Metotrexato/uso terapéutico , Ornitina , Fotólisis , Reproducibilidad de los Resultados
10.
Microorganisms ; 10(2)2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35208802

RESUMEN

We investigated the drug-resistant mechanisms of intracellular survival of methicillin-resistant S. aureus (MRSA). Our established MRSA clinical strain, OJ-1, with high biofilm-forming ability, and a macrophage cell line, J774A, were used. After ingestion of OJ-1 by J774A, the cells were incubated for ten days with vancomycin at doses 30 times higher than the minimum inhibitory concentration. The number of phagocytosed intracellular OJ-1 gradually decreased during the study but plateaued after day 7. In J774A cells with intracellular OJ-1, the expression of LysoTracker-positive lysosomes increased until day 5 and then declined from day 7. In contrast, LysoTracker-negative and OJ-1-retaining J774A cells became prominent from day 7, and intracellular OJ-1 also escaped from the autophagosome. Electron microscopy also demonstrated that OJ-1 escaped the phagosomes and was localized in the J774A cytoplasm. At the end of incubation, when vancomycin was withdrawn, OJ-1 started to grow vigorously. The present results indicate that intracellular phagocytosed biofilm-forming MRSA could survive for more than ten days by escaping the lysosomes and autophagosomes in macrophages. Intracellular MRSA may survive in macrophages, and accordingly, they could be resistant to antimicrobial drug treatments. However, the mechanisms their escape from the lysosomes are still unknown. Additional studies will be performed to clarify the lysosome-escaping mechanisms of biofilm-forming MRSA.

11.
J Vet Med Sci ; 83(12): 1933-1942, 2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34719609

RESUMEN

Hypertrophic scars found on the human body rarely develop in experimental animals, possibly due to their looser skin structure. This makes it difficult to understand the genesis of scar lesions. Therefore, appropriate animal models are urgently needed. In this study, we established a novel experimental model of a scar-forming wound by resecting a small portion of the abdominal muscle wall on the lower center of the abdomen in C57BL/6N mice, which are exposed to contractive forces by the surrounding muscle tissue. As a low-tension control, a back skin excision model was used with a splint fixed onto the excised skin edge, and granulation tissue formed on the muscle fascia supported by the back skeleton. One week after the resection, initial healing reactions, such as fibroblast proliferation, occurred in both models. However, after 21 days, lesions with collagen-rich granulation tissues, which were also accompanied by multiple nodular/spherical-like structures, developed only in the abdominal wall model. These lesions were analogous to scar lesions in humans. Therefore, the animal model developed in this study is unique in that fibrous scar tissues form under physiological conditions without using any artificial factors and is valuable for studying the pathogenesis and preclinical treatment of scar lesions.


Asunto(s)
Pared Abdominal , Cicatriz Hipertrófica , Enfermedades de los Roedores , Músculos Abdominales , Animales , Cicatriz Hipertrófica/patología , Cicatriz Hipertrófica/veterinaria , Ratones , Ratones Endogámicos C57BL , Cicatrización de Heridas
12.
Sci Rep ; 11(1): 18750, 2021 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-34548594

RESUMEN

Collagens act as cellular scaffolds in extracellular matrixes, and their breakdown products may also have important biological functions. We hypothesize that collagen dipeptide Pro-Hyp induces favorable healing activities and examined the effects of Pro-Hyp administered via different routes on wound healing using our novel murine model, in which an advanced fibrosis-prone scar lesion was developed in the abdominal muscle wall under the skin. After excising a part of the abdominal wall, a free-drinking experiment was performed using solutions with casein (CS), high molecular weight collagen peptides (HP), and low molecular weight collagen peptides including Pro-Hyp and Hyp-Gly (LP), in addition to water (HO). On day 21 of the study, when compared to the HO and CS groups, muscle regeneration in the LP group was significantly advanced in the granulation tissue, which was associated with a decrease in fibrosis. To clarify the effects of Pro-Hyp, daily intraperitoneal administration of pure Pro-Hyp was performed. Pro-Hyp administration induced many myogenically differentiated cells, including myogenin-positive myoblasts and myoglobin-positive myocytes, to migrate in the granulation tissue, while scar tissue decreased. These results indicated that Pro-Hyp administration accelerates muscle regenerative healing accompanied by less scarring after wounding on the abdominal wall.


Asunto(s)
Pared Abdominal/patología , Cicatriz/prevención & control , Colágeno/química , Dipéptidos/farmacología , Hidroxiprolina/administración & dosificación , Músculos/fisiopatología , Prolina/administración & dosificación , Cicatrización de Heridas/efectos de los fármacos , Administración Oral , Animales , Diferenciación Celular/efectos de los fármacos , Dipéptidos/administración & dosificación , Dipéptidos/química , Hidroxiprolina/química , Ratones , Músculos/patología , Prolina/química , Regeneración/efectos de los fármacos
13.
Biomolecules ; 11(5)2021 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-34066746

RESUMEN

Skin wounds greatly affect the global healthcare system, creating a substantial burden on the economy and society. Moreover, the situation is exacerbated by low healing rates, which in fact are overestimated in reports. Cutaneous wounds are generally classified into acute and chronic. The immune response plays an important role during acute wound healing. The activation of immune cells and factors initiate the inflammatory process, facilitate wound cleansing and promote subsequent tissue healing. However, dysregulation of the immune system during the wound healing process leads to persistent inflammation and delayed healing, which ultimately result in chronic wounds. The microenvironment of a chronic wound is characterized by high quantities of pro-inflammatory macrophages, overexpression of inflammatory mediators such as TNF-α and IL-1ß, increased activity of matrix metalloproteinases and abundance of reactive oxygen species. Moreover, chronic wounds are frequently complicated by bacterial biofilms, which perpetuate the inflammatory phase. Continuous inflammation and microbial biofilms make it very difficult for the chronic wounds to heal. In this review, we discuss the role of innate and adaptive immunity in the pathogenesis of acute and chronic wounds. Furthermore, we review the latest immunomodulatory therapeutic strategies, including modifying macrophage phenotype, regulating miRNA expression and targeting pro- and anti-inflammatory factors to improve wound healing.


Asunto(s)
Citocinas/metabolismo , Macrófagos/metabolismo , Cicatrización de Heridas/inmunología , Inmunidad Adaptativa , Animales , Humanos , Inmunidad Innata , Interleucina-1beta/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
14.
Front Cell Dev Biol ; 8: 638, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32760728

RESUMEN

Bioengineered materials are widely utilized due to their biocompatibility and degradability, as well as their moisturizing and antibacterial properties. One field of their application in medicine is to treat wounds by promoting tissue regeneration and improving wound healing. In addition to creating a physical and chemical barrier against primary infection, the mechanical stability of the porous structure of biomaterials provides an extracellular matrix (ECM)-like niche for cells. Growth factors (GFs) and cytokines, which are secreted by the cells, are essential parts of the complex process of tissue regeneration and wound healing. There are several clinically approved GFs for topical administration and direct injections. However, the limited time of bioactivity at the wound site often requires repeated drug administration that increases cost and may cause adverse side effects. The tissue regeneration promoting factors incorporated into the materials have significantly enhanced wound healing in comparison to bolus drug treatment. Biomaterials protect the cargos from protease degradation and provide sustainable drug delivery for an extended period of time. This prolonged drug bioactivity lowered the dosage, eliminated the need for repeated administration, and decreased the potential of undesirable side effects. In the following mini-review, recent advances in the field of single and combinatorial delivery of GFs and cytokines for treating cutaneous wound healing will be discussed.

15.
Front Cell Dev Biol ; 8: 548975, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33330443

RESUMEN

Many cells and soluble factors are involved in the wound healing process, which can be divided into inflammatory, proliferative, and remodeling phases. Fibroblasts play a crucial role in wound healing, especially during the proliferative phase, and show heterogeneity depending on lineage, tissue distribution, and extent of differentiation. Fibroblasts from tissue stem cells rather than from healthy tissues infiltrate wounds and proliferate. Some fibroblasts in the wound healing site express the mesenchymal stem cell marker, p75NTR. In the cell culture system, fibroblasts attached to collagen fibrils stop growing, even in the presence of protein growth factors, thus mimicking the quiescent nature of fibroblasts in healthy tissues. Fibroblasts in wound healing sites proliferate and are surrounded by collagen fibrils. These facts indicate presence of new growth-initiating factor for fibroblasts attached to collagen fibrils at the wound healing site, where the collagen-derived peptide, prolyl-hydroxyproline (Pro-Hyp), is generated. Pro-Hyp triggers the growth of p75NTR-positive fibroblasts cultured on collagen gel but not p75NTR-negative fibroblasts. Thus, Pro-Hyp is a low molecular weight growth-initiating factor for specific fibroblasts that is involved in the wound healing process. Pro-Hyp is also supplied to tissues by oral administration of gelatin or collagen hydrolysate. Thus, supplementation of gelatin or collagen hydrolysate has therapeutic potential for chronic wounds. Animal studies and human clinical trials have demonstrated that the ingestion of gelatin or collagen hydrolysate enhances the healing of pressure ulcers in animals and humans and improves delayed wound healing in diabetic animals. Therefore, the low molecular weight fibroblast growth-initiating factor, Pro-Hyp, plays a significant role in wound healing and has therapeutic potential for chronic wounds.

16.
Healthcare (Basel) ; 8(4)2020 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-33255590

RESUMEN

Negative pressure wound therapy (NPWT) has been commonly used over the years for a wide range of chronic/refractory lesions. Alternatively, autologous micrografting technology is recently becoming a powerful modality for initiating wound healing. The case presented is of a patient with a lower leg ulcer that had responded poorly to NPWT alone for three weeks. Consequently, the patient was put on a combination therapy of NPWT and micrografting. After injection of a dermal tissue micrografts suspension into the entire wound bed, NPWT was performed successively for two weeks, resulting in fresh granulation tissue formation. Thereafter, the autologous skin graft was taken well. This case study indicates that for a chronic/refractory ulcer patient with poor NPWT outcome, combination therapy using micrografting treatment and NPWT could rapidly initiate and enhance granulation tissue formation, creating a favorable bedding for subsequent skin grafting.

17.
Artículo en Inglés | MEDLINE | ID: mdl-32426341

RESUMEN

Growth factors and cytokines that are secreted by cells play a crucial role in the complex physiological reaction to tissue injury. The ability to spatially and temporally control their actions to maximize regenerative benefits and minimize side effects will help accelerate wound healing and improve tissue regeneration. In this study, the sequential targeted delivery of growth factor/cytokine combinations with regulatory functions on inflammation and tissue regeneration was examined using an internal splint wound healing model. Four examined growth factors and cytokines were effectively incorporated into a novel chitosan-based cryogel, which offered a controlled and sustained release of all factors while maintaining their biological activities. The cryogels incorporated with inflammation modulatory factors (IL-10 and TGF-ß) and with wound healing factors (VEGF and FGF) were placed on the wound surface on day 0 and day 3, respectively, after wound initiation. Although wound area gradually decreased in all groups over time, the area in the cryogel group with growth factor/cytokine combinations was significantly reduced starting on day 7 and reached about 10% on day 10, as compared to 60-65% in the control groups. Sequential delivery of inflammation modulatory and wound healing factors enhanced granulation tissue formation, as well as functional neovascularization, leading to regenerative epithelialization. Collectively, the chitosan-based cryogel can serve as a controlled release system for sequential delivery of several growth factors and cytokines to accelerate tissue repair and regeneration.

18.
Microorganisms ; 8(10)2020 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-33050001

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA), the most commonly detected drug-resistant microbe in hospitals, adheres to substrates and forms biofilms that are resistant to immunological responses and antimicrobial drugs. Currently, there is a need to develop alternative approaches for treating infections caused by biofilms to prevent delays in wound healing. Silver has long been used as a disinfectant, which is non-specific and has relatively low cytotoxicity. Silver sulfadiazine (SSD) is a chemical complex clinically used for the prevention of wound infections after injury. However, its effects on biofilms are still unclear. In this study, we aimed to analyze the mechanisms underlying SSD action on biofilms formed by MRSA. The antibacterial effects of SSD were a result of silver ions and not sulfadiazine. Ionized silver from SSD in culture media was lower than that from silver nitrate; however, SSD, rather than silver nitrate, eradicated mature biofilms by bacterial killing. In SSD, sulfadiazine selectively bound to biofilms, and silver ions were then liberated. Consequently, the addition of an ion-chelator reduced the bactericidal effects of SSD on biofilms. These results indicate that SSD is an effective compound for the eradication of biofilms; thus, SSD should be used for the removal of biofilms formed on wounds.

19.
Artículo en Inglés | MEDLINE | ID: mdl-32071730

RESUMEN

BACKGROUND: Inappropriate dosing of direct oral anticoagulants (DOACs) has been associated with clinical safety and efficacy; however, little is known about clinical data associated with an inappropriate DOAC dosing in Japan. In addition, there is no report in which the appropriateness of DOAC dosing between prescription for inpatients and for outpatients was examined. In this study, we aimed to investigate the prevalence and factors associated in the inappropriate dosing of DOACs in patients with atrial fibrillation (AF). METHODS: The retrospective cohort study was conducted at a single Japanese university hospital. Both inpatients and outpatients, who were diagnosed with AF and for whom treatment with either dabigatran, rivaroxaban, apixaban, or edoxaban was initiated between April 1, 2014 and March 31, 2018, were enrolled in the study. Appropriateness of DOAC dosing was assessed according to the manufacturer's labeling recommendations (dose reduction criteria) of each DOAC. Inappropriate reduced dose, namely, underdosing, was defined as prescription of a reduced dose of DOAC despite the patient not meeting the dose reduction criteria. Inappropriate standard dose, namely, overdosing, was defined as prescription of a standard dose of DOAC despite the patient meeting the dose reduction criteria. Inappropriate DOAC dosing was defined as a deviation of the recommended dose (both underdosing and overdosing). RESULTS: A total of 316 patients (dabigatran, 28; rivaroxaban, 107; apixaban, 116; and edoxaban, 65) were included, with a median (interquartile range) age of 75 (66-81) years and 62.3% male. DOACs were prescribed at an appropriate standard dose in 39.2% of patients, an appropriate reduced dose in 36.7%, an inappropriate standard dose in 2.5%, and an inappropriate reduced dose in 19.3%. Multivariate analysis revealed that the inappropriate dosing of DOACs was significantly associated with prescriptions for outpatients (vs. inpatients; odds ratio [OR] 2.87, 95% confidence interval [CI] 1.53-5.62, p < 0.001) and those with higher HAS-BLED scores (OR 1.87, 95% CI 1.42-2.51, p < 0.001). CONCLUSIONS: Our results demonstrated that the inappropriate dosing of DOACs occurred in approximately 20% of AF patients, and was more frequent in outpatients (vs. inpatients) and in those with a higher risk of bleeding. It is recommended that pharmacists play a greater role in assisting in the prescription process to help physicians make better decisions.

20.
Pathol Int ; 59(8): 501-21, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19627534

RESUMEN

This article reviews problems in diagnostic pathology and molecular cytogenetics of soft-tissue tumors. Also discussed are the origin of soft-tissue sarcomas and the molecular basis of effective target therapy for sarcomas. Molecular cytogenetic analysis of tumor-specific chromosomal translocations and associated fusion gene transcripts offers a useful adjunct to the diagnosis of soft-tissue tumors, but recent studies have indicated a growing number of fusion gene variations in each tumor type. In pleomorphic sarcoma/malignant fibrous histiocytoma, the alternative lengthening of telomeres (ALT) mechanism may result in formation of anaphase bridges and marked nuclear pleomorphism. The histogenesis of soft-tissue sarcomas has been a matter of controversy. In the present experimental model using s.c. injection of 3-methylcholanthrene in C57BL/6 mice pretreated with bone marrow-transplantation from green fluorescent protein (GFP)-positive green mice, the bone marrow-derived mesenchymal stem cells as well as the tissue-resident mesenchymal cells in the peripheral soft tissues are possible originators of sarcomagenesis. Little is known about a molecular basis of target therapy for sarcomas. Platelet-derived growth factor-BB (PDGF-BB) enhances the invasive activity of malignant peripheral nerve sheath tumor (MPNST) cells through platelet-derived growth factor receptor (PDGFR) phosphorylation, whereas imatinib mesylate inhibited such activity, suggesting that targeting PDGFR-beta may result in the establishment of novel treatment for MPNST. In addition, emmprin is a transmembrane glycoprotein on tumor cells that stimulates peritumoral fibroblasts to produce matrix metalloproteinases (MMP), playing a crucial role in tumor progression, invasion and metastasis. The MMP upregulation mechanism mediated by tumor-associated emmprin may be a potentially useful target in anti-tumor invasion therapy for sarcomas.


Asunto(s)
Neoplasias de los Tejidos Blandos/diagnóstico , Neoplasias de los Tejidos Blandos/genética , Animales , Humanos , Neoplasias de los Tejidos Blandos/terapia
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