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1.
Infect Immun ; 87(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31527127

RESUMO

Staphylococcus aureus extracellular DNA (eDNA) plays a crucial role in the structural stability of biofilms during bacterial colonization; on the contrary, host immune responses can be induced by bacterial eDNA. Previously, we observed production of S. aureus thermonuclease during the early stages of biofilm formation in a mammalian cell culture medium. Using a fluorescence resonance energy transfer (FRET)-based assay, we detected thermonuclease activity of S. aureus biofilms grown in Iscove's modified Dulbecco's medium (IMDM) earlier than that of widely studied biofilms grown in tryptic soy broth (TSB). The thermonuclease found was Nuc1, confirmed by mass spectrometry and competitive Luminex assay. These results indicate that biofilm development in IMDM may not rely on eDNA for structural stability. A bacterial viability assay in combination with wheat germ agglutinin (WGA) staining confirmed the accumulation of dead cells and eDNA in biofilms grown in TSB. However, in biofilms grown in IMDM, minimal amounts of eDNA were found; instead, polysaccharide intercellular adhesin (PIA) was detected. To investigate if this early production of thermonuclease plays a role in immune modulation by biofilm, we studied the effect of thermonuclease on human neutrophil extracellular trap (NET) formation using a nuc knockout and complemented strain. We confirmed that thermonuclease produced by early-stage biofilms grown in IMDM degraded biofilm-induced NETs. Additionally, neither the presence of biofilms nor thermonuclease stimulated an increase in reactive oxygen species (ROS) production by neutrophils. Our findings indicated that S. aureus, during the early stages of biofilm formation, actively evades the host immune responses by producing thermonuclease.


Assuntos
Biofilmes/crescimento & desenvolvimento , Armadilhas Extracelulares/metabolismo , Nuclease do Micrococo/metabolismo , Neutrófilos/imunologia , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/patogenicidade , Transferência Ressonante de Energia de Fluorescência , Humanos , Viabilidade Microbiana , Polissacarídeos Bacterianos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/metabolismo
2.
Muscle Nerve ; 60(5): 520-527, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31281987

RESUMO

INTRODUCTION: Loss of sensation due to diabetes-related neuropathy often leads to diabetic foot ulceration. Several test instruments are used to assess sensation, such as static and moving 2-point discrimination (S2PD, M2PD), monofilaments, and tuning forks. METHODS: Mokken scale analysis was applied to the Rotterdam Diabetic Foot Study data to select hierarchies of tests to construct measurement scales. RESULTS: We developed 39-item and 31-item scales to measure loss of sensation for research purposes and a 13-item scale for clinical practice. All instruments were strongly scalable and reliable. The 39 items can be classified into 5 hierarchically ordered core clusters: S2PD, M2PD, vibration sense, monofilaments, and prior ulcer or amputation. DISCUSSION: Guided by the presented scales, clinicians may better classify the grade of sensory loss in diabetic patients' feet. Thus, a more personalized approach concerning individual recommendations, intervention strategies, and patient information may be applied.


Assuntos
Pé Diabético/diagnóstico , Limiar Sensorial , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Pé Diabético/fisiopatologia , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Estudos Prospectivos , Índice de Gravidade de Doença , Vibração
3.
Int Wound J ; 16(6): 1339-1346, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31418528

RESUMO

The aim of this study was to identify diabetic foot ulcer (DFU) patients at risk for the development of a hard-to-heal wound. This is a post-hoc analysis of a prospective cohort study including a total of 208 patients with a DFU. The primary endpoints were time to healing and the development of a hard-to-heal-wound. Univariable and multivariable logistic and Cox regression analysis were used to study the associations of patient characteristics with the primary endpoints. The number of previous DFUs [odds ratio (OR): 1.42, 95% confidence interval (CI): 1.01-1.99, P = .04], University of Texas (UT) classification grade 2 (OR: 2.93, 95% CI: 1.27-6.72, P = .01), UT classification grade 3 (OR: 2.80, 95% CI: 1.17-6.71, P = .02), and a diagnosis of foot stand deformation (OR: 1.54, 95% CI: 0.77-3.08, P = .05) were significantly associated with the development of a hard-to-heal wound. Only UT classification grade 3 (HR: 0.61, 95% CI: 0.41-0.90, P = .01) was associated with time to healing. The number of previous DFUs, UT classification grade, and a diagnosis of foot deformation are significantly associated with development of a hard-to-heal wound in patients with a DFU. The only predictor significantly associated with time to healing was UT classification grade 3. These patient characteristics can be used to identify patients at risk for the development of hard-to-heal wounds, who might need an early intervention to prevent wound problems.


Assuntos
Pé Diabético/fisiopatologia , Cicatrização/fisiologia , Estudos de Coortes , Pé Diabético/classificação , Feminino , Estudo Historicamente Controlado , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Índice de Gravidade de Doença
4.
Muscle Nerve ; 58(4): 559-565, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30028522

RESUMO

INTRODUCTION: Static- and moving 2-point discrimination (S2PD, M2PD), 10-g monofilaments- and tuning fork are validated outcome measures of clinical manifestations of diabetes-related neuropathy. No modern statistical techniques have been used to investigate how well these instruments combine to measure sensory loss. METHODS: To grade sensory loss at the feet, we fitted parametric forms of Item Response Theory models to the data of these instruments. RESULTS: The fit statistics indicate that the loss of sensation is gradable, with readily available instruments. S2PD and M2PD are lost first, followed by vibration sense, the 10-g monofilament and the ability to feel a cold stimulus. CONCLUSIONS: This test battery appears to provide sound measurement properties in a group of diabetic patients with diverse amounts of sensory loss. This approach may be used in clinical practice to grade sensory loss reliably and quickly, with instruments that are easy to use. Muscle Nerve 58: 559-565, 2018.


Assuntos
Neuropatias Diabéticas/fisiopatologia , Pé/inervação , Distúrbios Somatossensoriais/fisiopatologia , Idoso , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/etiologia , Pé Diabético/fisiopatologia , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/etiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Psicometria , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Distúrbios Somatossensoriais/diagnóstico , Distúrbios Somatossensoriais/etiologia
5.
Wound Repair Regen ; 26(1): 16-26, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29453855

RESUMO

In this study, we investigated whether postburn itch in rats, after a full thickness burn, is correlated to the nervous reinnervation of the burn wound area. For this purpose, we determined scratching duration (expressed as second/hour) at 24 hours, 2, 4, 8, and 12 weeks postburn and combined this with immunohistochemistry for protein gene product 9.5 (PGP9.5) to identify all nerve fibers, calcitonin gene related peptide (CGRP) to identify peptidergic fibers, tyrosine hydroxylase (TH) for sympathetic fibers, and growth-associated protein 43 (GAP-43) for regrowing fibers. We found a modest, but highly significant, increase in scratching duration of all burn wound rats from 3 to 12 weeks postburn (maximally 63 ± 9.5 second/hour compared to sham 3.1 ± 1.4 second/hour at 9 weeks). At 24 hours postburn, all nerve fibers had disappeared from the burn area. Around 4 weeks postburn PGP 9.5- and CGRP-immunoreactive nerve fibers returned to control levels. TH- and GAP-43-IR nerve fibers, which we found to be almost completely colocalized, did not regrow. No correlation was found between scratching duration and nervous reinnervation of the skin. The present results suggest that in rat, like in human, burn wound healing will induce increased scratching, which is not correlated to the appearance of nervous reinnervation.


Assuntos
Queimaduras/patologia , Regeneração Nervosa/fisiologia , Nervos Periféricos/fisiologia , Prurido/etiologia , Pele/inervação , Cicatrização/fisiologia , Animais , Comportamento Animal , Biópsia por Agulha , Queimaduras/complicações , Modelos Animais de Doenças , Imunofluorescência , Imuno-Histoquímica , Masculino , Fibras Nervosas/patologia , Países Baixos , Prurido/fisiopatologia , Distribuição Aleatória , Ratos , Ratos Wistar , Sensibilidade e Especificidade , Pele/patologia
6.
Glycoconj J ; 34(3): 325-338, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27924424

RESUMO

The importance of extracellular matrix (ECM) integrity in maintaining normal tissue function is highlighted by numerous pathologies and situations of acute and chronic injury associated with dysregulation or destruction of ECM components. Heparan sulfate (HS) is a key component of the ECM, where it fulfils important functions associated with tissue homeostasis. Its degradation following tissue injury disrupts this delicate equilibrium and may impair the wound healing process. ReGeneraTing Agents (RGTA®s) are polysaccharides specifically designed to replace degraded HS in injured tissues. The unique properties of RGTA® (resistance to degradation, binding and protection of ECM structural and signaling proteins, like HS) permit the reconstruction of the ECM, restoring both structural and biochemical functions to this essential substrate, and facilitating the processes of tissue repair and regeneration. Here, we review 25 years of research surrounding this HS mimic, supporting the mode of action, pre-clinical studies and therapeutic efficacy of RGTA® in the clinic, and discuss the potential of RGTA® in new branches of regenerative medicine.


Assuntos
Materiais Biomiméticos/farmacologia , Lesões da Córnea/tratamento farmacológico , Glicosaminoglicanos/farmacologia , Substâncias Protetoras/farmacologia , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Materiais Biomiméticos/química , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/lesões , Ensaios Clínicos como Assunto , Lesões da Córnea/reabilitação , Avaliação Pré-Clínica de Medicamentos , Matriz Extracelular/química , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/lesões , Glicosaminoglicanos/química , Heparitina Sulfato/química , Heparitina Sulfato/farmacologia , Humanos , Músculos/efeitos dos fármacos , Músculos/lesões , Substâncias Protetoras/química , Medicina Regenerativa/métodos , Pele/lesões , Alicerces Teciduais
7.
Muscle Nerve ; 56(3): 399-407, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-27977868

RESUMO

INTRODUCTION: No data are available for normative values of cutaneous threshold and spatial discrimination in the feet. We developed clinically applicable reference values in relation to the nerve distributions of the feet. METHODS: We determined foot sensation in 196 healthy individuals. Cutaneous threshold (1-point static discrimination, S1PD) was tested with monofilaments (0.008 to 300 gram) and spatial discrimination (2-point static [S2PD] and moving [M2PD] discrimination) on five locations per foot. RESULTS: There was a significant age-dependent increase in S1PD, S2PD, and M2PD values (P < 0.05). No significant differences were found between both feet. S1PD values differed up to 0.8 g between genders. There were no significant differences between genders for S2PD and M2PD measurements. M2PD values were generally lower than S2PD values. CONCLUSIONS: This study provides age-related normative values for foot sensation to help clinicians assess sensory deficits in relation to aging and identify patients with underlying nerve problems. Muscle Nerve 56: 399-407, 2017.


Assuntos
Envelhecimento/fisiologia , Discriminação Psicológica/fisiologia , Pé/fisiologia , Limiar Sensorial/fisiologia , Tato/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Pé/inervação , Humanos , Masculino , Pessoa de Meia-Idade , Vibração , Adulto Jovem
8.
Ann Rheum Dis ; 73(2): 365-75, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23349130

RESUMO

OBJECTIVE: To assess the value of advanced imaging techniques in the detection of hand osteoarthritis (OA) and hand OA progression. METHODS: PubMed/Medline and Embase were searched until April 2012 for studies on imaging of hand OA that presented quantitative data on validity, reliability or responsiveness. Articles presenting only data on conventional radiography (CR) were excluded. Methodological quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist for validity, the Quality Appraisal of Reliability Studies (QAREL) for reliability and the COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) for responsiveness. RESULTS: Of 627 citations, 25 studies on ultrasonography (US), MRI or scintigraphy were included. No studies on CT, positron emission tomography or single photon emission CT met our eligibility criteria. Validity was generally assessed against healthy controls, CR or clinical examination. Overall, US and MRI detected more disease than CR and found significant differences between patients and healthy controls. Scintigraphy detected fewer pathological joints than CR. Intra- and inter-reader reliability varied for US (κ=0.01-1.0) and MRI (κ=0.15-0.84 and intraclass correlation coefficient=0.21-0.99) and was good for scintigraphy (κ=0.61-0.84). There were no responsiveness studies for MRI. US responsiveness studies showed a reduction of soft-tissue changes after treatment which correlated with decrease in pain (r=0.7-0.8). For scintigraphy, scores decreased over time while CR showed progression of hand OA. CONCLUSIONS: MRI and US seem to be the most promising candidates for early detection of hand OA and for future use in clinical trials. However, further research is needed to improve scoring methods, to compare US with MRI, to confirm reliability of MRI and to further determine the responsiveness of US and MRI.


Assuntos
Articulação da Mão/patologia , Osteoartrite/diagnóstico , Progressão da Doença , Diagnóstico Precoce , Articulação da Mão/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Osteoartrite/diagnóstico por imagem , Reprodutibilidade dos Testes , Ultrassonografia
9.
Med Eng Phys ; 124: 104096, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38418025

RESUMO

INTRODUCTION: Pressure Ulcers (PUs) are a major healthcare issue leading to prolonged hospital stays and decreased quality of life. Monitoring body position changes using sensors could reduce workload, improve turn compliance and decrease PU incidence. METHOD: This systematic review assessed the clinical applicability of different sensor types capable of in-bed body position detection. RESULTS: We included 39 articles. Inertial sensors were most commonly used (n = 14). This sensor type has high accuracy and is equipped with a 2-4 hour turn-interval warning system increasing turn compliance. The second-largest group were piezoresistive (pressure) sensors (n = 12), followed by load sensors (n = 4), piezoelectric sensors (n = 3), radio wave-based sensors (n = 3) and capacitive sensors (n = 3). All sensor types except inertial sensors showed a large variety in the type and number of detected body positions. However, clinically relevant position changes such as trunk rotation and head of bed elevation were not detected or tested. CONCLUSION: Inertial sensors are the benchmark sensor type regarding accuracy and clinical applicability but these sensors have direct patient contact and (re)applying the sensors requires the effort of a nurse. Other sensor types without these disadvantages should be further investigated and developed. We propose the Pressure Ulcer Position System (PUPS) guideline to facilitate this.


Assuntos
Úlcera por Pressão , Humanos , Úlcera por Pressão/diagnóstico , Pessoas Acamadas , Qualidade de Vida , Postura
10.
Skeletal Radiol ; 42(5): 715-21, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23455704

RESUMO

OBJECTIVE: To compare computed tomography (CT) with digital radiography for the detection of osteoarthritis (OA) of the first carpometacarpal (CMC1) and scaphotrapeziotrapezoid (STT) joint. MATERIALS AND METHODS: We retrospectively identified patients who were assessed for CMC1 OA or STT OA at our hand surgery outpatient clinic between January 2008 and March 2011, and who had both a digital radiograph and a CT scan of the hand within a 3-month period. CT and radiographic images were scored independently by two musculoskeletal radiologists for joint space narrowing (JSN), osteophytes, subchondral sclerosis, bone cysts, and erosions in the CMC1 and STT joints. RESULTS: Thirty patients were identified. The inter-reader reliability of CT for the detection of CMC1 OA (ICC 1.00) and STT OA (ICC 0.80) was higher than radiography (ICC's 0.15 and 0.45). In comparison with their own radiographical scoring, both readers detected with CT 3 more patients with CMC1 OA, and 13 and 5 more patients with STT OA. CONCLUSION: Computed tomography had a higher inter-reader reliability and detection rate for both CMC1 and STT OA, compared with radiography. As surgical treatment selection of thumb base OA depends on the presence of pathology in the CMC1 and STT joints, CT may improve treatment selection and surgical planning.


Assuntos
Osteoartrite/diagnóstico por imagem , Polegar/diagnóstico por imagem , Articulação do Punho/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Intensificação de Imagem Radiográfica , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
11.
Cells Tissues Organs ; 195(3): 185-96, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21494020

RESUMO

The aim of this study was to create and characterize a tissue-engineered mucosal equivalent (TEM) that closely resembles native mucosa. TEM consists of human primary keratinocytes and fibroblasts isolated from biopsies taken from healthy donors and seeded onto a de-epidermized dermis and cultured for 14 days at the air/liquid interface. The structure of TEM was examined and compared with native nonkeratinizing oral mucosa (NNOM). The various components of the newly formed epidermal layer, basement membrane and underlying connective tissue were analyzed using immunohistochemistry. The mucosal substitute presented in this study showed a mature stratified squamous epithelium that was similar to that of native oral mucosa, as demonstrated by K19, desmoglein-3 and involucrin staining. In addition, the expression of basement membrane components collagen type IV, laminin-5 and integrin α6 and ß4 in TEM proved to be consistent with native oral mucosa. The expression of PAS, Ki67, K10 and K13, however, appeared to be different in TEM compared to NNOM. Nevertheless, the similarities with native oral mucosa makes TEM a promising tool for studying the biology of mucosal pathologies such as oral mucositis or fibrosis as well as the development of new therapies.


Assuntos
Fibroblastos/metabolismo , Queratinócitos/metabolismo , Mucosa Bucal/citologia , Mucosa Bucal/metabolismo , Engenharia Tecidual/métodos , Diferenciação Celular/fisiologia , Processos de Crescimento Celular/fisiologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Fibroblastos/citologia , Humanos , Imuno-Histoquímica , Queratinócitos/citologia , Queratinas/biossíntese , Masculino , Pessoa de Meia-Idade , Pele/citologia , Pele/metabolismo
12.
J Oral Pathol Med ; 41(6): 477-83, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22233383

RESUMO

BACKGROUND: This study focuses on the potential of ReGeneraTing Agent OTR4120 (RGTA-OTR4120) to treat radiation-induced damage of salivary glands. RGTAs are biopolymers designed to mimic the effects of heparan sulphate, thereby stimulation tissue repair and regeneration. METHODS: C3H mice were irradiated with a single dose of 15 Gy in the head and neck region. RGTA-OTR4120 was injected 24 h after radiotherapy, followed by weekly injections. At 2, 6 and 10 weeks after radiotherapy, salivary flow rates were measured and animals were sacrificed to obtain parotid and submandibular glands for histology. Periodic acid Schiff stain was performed to visualize mucins that are produced by acinar cells. Amylase and total protein content were measured in saliva samples. RESULTS: Salivary flow rates were increased at 2 weeks, but not at 6 and 10 weeks after radiotherapy with RGTA-OTR4120 administration, compared to irradiated controls. Two and 10 weeks after radiotherapy, the mucin production activity of acinar cells was increased under influence of RGTA administration. RGTA-OTR4120 did not influence amylase or total protein secretion. CONCLUSION: RGTA-OTR4120 administration has a positive effect on salivary flow rates in irradiated mice on the short term. The effect was absent 10 weeks after radiotherapy, while at that time point, mucin producing activity of acinar cells was elevated by RGTA-OTR4120 administration. Given these results and the advantages of RGTA use in irradiated patients, further investigation on the potential of this drug to treat radiation-induced salivary gland damage, alone or in combination with other drugs, such as amifostine, is suggested.


Assuntos
Materiais Biomiméticos/uso terapêutico , Glicosaminoglicanos/uso terapêutico , Heparitina Sulfato , Lesões por Radiação/tratamento farmacológico , Glândulas Salivares/efeitos da radiação , Células Acinares/efeitos dos fármacos , Células Acinares/patologia , Células Acinares/efeitos da radiação , Amilases/análise , Animais , Feminino , Injeções , Camundongos , Camundongos Endogâmicos C3H , Mucinas/análise , Glândula Parótida/efeitos dos fármacos , Glândula Parótida/patologia , Glândula Parótida/efeitos da radiação , Doses de Radiação , Distribuição Aleatória , Saliva/efeitos dos fármacos , Saliva/metabolismo , Saliva/efeitos da radiação , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/metabolismo , Proteínas e Peptídeos Salivares/análise , Taxa Secretória/efeitos dos fármacos , Taxa Secretória/efeitos da radiação , Glândula Submandibular/efeitos dos fármacos , Glândula Submandibular/patologia , Glândula Submandibular/efeitos da radiação , Fatores de Tempo
13.
Acta Biomater ; 151: 346-359, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35995408

RESUMO

A functional vascular system is a prerequisite for bone repair as disturbed angiogenesis often causes non-union. Paracrine factors released from human bone marrow derived mesenchymal stromal cells (BMSCs) have angiogenic effects on endothelial cells. However, whether these paracrine factors participate in blood flow dynamics within bone capillaries remains poorly understood. Here, we used two different microfluidic designs to investigate critical steps during angiogenesis and found pronounced effects of endothelial cell proliferation as well as chemotactic and mechanotactic migration induced by BMSC conditioned medium (CM). The application of BMSC-CM in dynamic cultures demonstrates that bioactive factors in combination with fluidic flow-induced biomechanical signals significantly enhanced endothelial cell migration. Transcriptional analyses of endothelial cells demonstrate the induction of a unique gene expression profile related to tricarboxylic acid cycle and energy metabolism by the combination of BMSC-CM factors and shear stress, which opens an interesting avenue to explore during fracture healing. Our results stress the importance of in vivo - like microenvironments simultaneously including biochemical, biomechanical and oxygen levels when investigating key events during vessel repair. STATEMENT OF SIGNIFICANCE: Our results demonstrate the importance of recapitulating in vivo - like microenvironments when investigating key events during vessel repair. Endothelial cells exhibit enhanced angiogenesis characteristics when simultaneous exposing them to hMSC-CM, mechanical forces and biochemical signals simultaneously. The improved angiogenesis may not only result from the direct effect of growth factors, but also by reprogramming of endothelial cell metabolism. Moreover, with this model we demonstrated a synergistic impact of mechanical forces and biochemical factors on endothelial cell behavior and the expression of genes involved in the TCA cycle and energy metabolism, which opens an interesting new avenue to stimulate angiogenesis during fracture healing.


Assuntos
Células Endoteliais , Células-Tronco Mesenquimais , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Humanos , Microfluídica , Neovascularização Fisiológica , Oxigênio/farmacologia
14.
Wound Repair Regen ; 19(4): 505-14, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21649786

RESUMO

Pressure ulcers are a major clinical problem, with a large burden on healthcare resources. This study evaluated the effects of the heparan sulfate glycosaminoglycan mimetic, OTR4120, on pressure ulceration and healing. Ischemia-reperfusion (I-R) was evoked to induce pressure ulcers by external clamping and then removal of a pair of magnet disks on rat dorsal skin for a single ischemic period of 16 hours. Immediately after magnet removal, rats received an intramuscular injection of OTR4120 weekly for up to 1 month. During the ischemic period, normal skin perfusion was reduced by at least 60% and at least 20-45% reperfused into the ischemic region after compression release. This model caused sustained skin incomplete necrosis for up to 14 days and led to grade 2-3 ulcers. OTR4120 treatment decreased the area of skin incomplete necrosis and degree of ulceration. OTR4120 treatment also reduced inflammation and increased angiogenesis. In OTR4120-treated ulcers, the contents of vascular endothelial growth factor, platelet-derived growth factor, and transforming growth factor beta-1 were increased. Moreover, OTR4120 treatment promoted early expression of alpha-smooth muscle actin and increased collagen biosynthesis. Long-term restoration of wounded tissue biomechanical strength was significantly enhanced after OTR4120 treatment. Taken together, we conclude that OTR4120 treatment reduces pressure ulcer formation and potentiates the internal healing bioavailability.


Assuntos
Glicosaminoglicanos/farmacologia , Úlcera por Pressão/terapia , Cicatrização/efeitos dos fármacos , Actinas/metabolismo , Animais , Fenômenos Biomecânicos , Colágeno/biossíntese , Modelos Animais de Doenças , Feminino , Inflamação/tratamento farmacológico , Injeções Intramusculares , Neovascularização Fisiológica/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Ratos , Traumatismo por Reperfusão , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
Muscle Nerve ; 40(6): 967-75, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19771597

RESUMO

Ultrasound-guided near-nerve neurography is a new tool that can be used to assess nerve regeneration before reinnervation occurs. In this study, ultrasound-guided near-nerve measurements were validated against axon diameter counts in rabbits during a 15-week regeneration period after a crush lesion of their peroneal nerve. The course of the nerve was determined ultrasonically, and the active near-nerve needle electrode was maneuvered just next to the nerve under ultrasound guidance. Measured action potentials were compared with axon diameter counts from histological sections of these same nerves. A moderate to good positive correlation was found, which reached a maximum of 0.7 at a cut-off of 3 microm, corresponding to the minimal size of the myelinated axons. Our results suggest that, following a similar validation study in humans, ultrasound-guided near-nerve neurography may be clinically useful when early evaluation of nerve activity is needed.


Assuntos
Regeneração Nervosa , Traumatismos dos Nervos Periféricos , Nervos Periféricos/diagnóstico por imagem , Animais , Axônios/diagnóstico por imagem , Axônios/patologia , Técnicas de Diagnóstico Neurológico , Masculino , Nervos Periféricos/patologia , Coelhos , Ultrassonografia/métodos
16.
Wound Repair Regen ; 17(6): 840-52, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19903305

RESUMO

Heparan sulfate glycosaminoglycans (HS-GAGs) are not only the structural elements of tissue architecture but also regulate the bioavailability and transduction pathways of heparan sulfate-bound polypeptides released by cells or the extracellular matrix. Heparan sulfate-bound polypeptides include inflammatory mediators, chemokines, angiogenic factors, morphogens, and growth-promoting factors that induce cell migration, proliferation, and differentiation in wound healing. OTR4120, a polymer engineered to mimic the properties of HS-GAGs, is used to replace the natural HS-GAGs that are degraded during wound repair, and enhance the tissue regeneration by preserving the cellular microenvironment and the endogenous signals needed for tissue regeneration. We previously demonstrated that OTR4120 treatment had a long-term effect on increasing breaking strength and vasodilation in healing rat full-thickness excisional wounds. The present study investigates the underlying mechanisms of the effects of OTR4120 treatment in improving the quality of cutaneous wound repair. We found that OTR4120 treatment stimulated inflammation resolution and increased neovascularization. OTR4120 treatment also promoted epidermal migration and proliferation during reepithelialization. Moreover, the granulation tissue formation and collagen maturation were improved in OTR4120-treated wounds. Three months after wounding, the effects of OTR4120 treatment on vascularization and inflammation resolution were normalized, except for an improved neodermis. We conclude that OTR4120 is a potential matrix therapeutic agent that ensures the quality of normal cutaneous wound repair and may restore impaired wound healing characterized by deficient angiogenesis and prolonged inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Colágeno/efeitos dos fármacos , Glicosaminoglicanos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Úlcera Cutânea/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Inflamação/fisiopatologia , Masculino , Neovascularização Fisiológica/fisiologia , Ratos , Úlcera Cutânea/fisiopatologia , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Cicatrização/fisiologia
17.
J Oral Maxillofac Surg ; 67(2): 292-300, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19138602

RESUMO

PURPOSE: The inferior alveolar nerve (IAN) can be injured during trauma or surgery. So far there is no consensus for evaluating IAN injury. This study aimed to identify a testing method suitable for daily clinical practice which allows us to identify nerve injury, grade its severity, and monitor its recovery. MATERIALS AND METHODS: Covering a 20-year period, prospective studies on sensory changes after mandibular procedures were reviewed regarding sensory testing methods; 75 studies on third molar removal, osteotomy, fracture, and implants were included. RESULTS: These studies reported varying incidences. In third molar removal and implant studies, a limited number of sensory tests were used, whereas in osteotomy and fracture studies more detailed testing was performed, using reproducible tests like light touch test with Semmes-Weinstein monofilaments and 2-point discrimination. CONCLUSIONS: Sensory function was not uniformly tested and presented, making a comparison of data impossible and highlighting the need for uniform testing methodology. Based on the results of this review, the light touch test with Semmes-Weinstein monofilaments for grading is recommended, using a grid and control site describing unilateral or bilateral nerve injury. Additionally, a visual analog scale-based questionnaire should be used to evaluate subjective sensibility. Using this method to test IAN injuries will allow comparison of future studies and provide valuable insight in the severity and prognosis of IAN injuries.


Assuntos
Traumatismos dos Nervos Cranianos/diagnóstico , Exame Neurológico/métodos , Distúrbios Somatossensoriais/diagnóstico , Traumatismos do Nervo Trigêmeo , Traumatismos dos Nervos Cranianos/etiologia , Implantação Dentária Endóssea/efeitos adversos , Humanos , Fraturas Mandibulares/complicações , Mecanorreceptores/fisiologia , Dente Serotino/cirurgia , Nociceptores/fisiologia , Osteotomia/efeitos adversos , Estudos Prospectivos , Inquéritos e Questionários , Sensação Térmica , Extração Dentária/efeitos adversos , Percepção do Tato
18.
J Hand Surg Am ; 34(9): 1689-95, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19766409

RESUMO

PURPOSE: Cold intolerance may impose great changes on patients' lifestyle, work, and leisure activities, and it is often severely disabling. This study aims to investigate the prevalence and severity of cold intolerance in patients with injury-related neuromas of the upper extremity and improvement of symptoms after surgical treatment. Furthermore, we try to find predictors for cold intolerance and correlations with other symptoms. METHODS: Between January 2006 and February 2009, 34 consecutive patients with surgically treated neuroma-specific neuropathic pain of the upper extremities were sent a questionnaire composed of general questions concerning epidemiologic variables and several specific validated questionnaires, including the Visual Analog Scale for pain. To estimate the prevalence of cold intolerance objectively in neuroma patients, we used the validated CISS (Cold Intolerance Symptom Severity) questionnaire with a prespecified cutoff point. RESULTS: The CISS questionnaire was filled out by 33 patients before and 30 after surgery for neuroma-specific neuropathic pain, with a mean follow-up time of 24 months. We found a prevalence of cold intolerance of 91% before surgery, with a mean CISS score above the cutoff point for abnormal cold intolerance. After surgery, the prevalence of cold intolerance and the mean CISS score were not significantly different, whereas the mean Visual Analog Scale score decreased significantly (p < .01). CISS scores were lower in patients with neuromas associated with sharp injury of the peripheral nerve (p = .02). A higher VAS score correlated significantly with a higher CISS score (p = .01). CONCLUSIONS: Cold intolerance is a difficult and persistent problem that has a high prevalence in patients with a painful injury-related neuroma. There seems to be a relationship between severity of cold intolerance as measured by CISS, pain as measured by the Visual Analog Scale, and type of injury. Cold intolerance may not disappear with time or surgical treatment. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Assuntos
Temperatura Baixa/efeitos adversos , Neuroma/fisiopatologia , Neuroma/cirurgia , Neoplasias do Sistema Nervoso Periférico/fisiopatologia , Neoplasias do Sistema Nervoso Periférico/cirurgia , Extremidade Superior/lesões , Adulto , Feminino , Humanos , Masculino , Neuralgia/etiologia , Neuroma/complicações , Medição da Dor , Neoplasias do Sistema Nervoso Periférico/complicações , Inquéritos e Questionários , Extremidade Superior/inervação
19.
Diabetes Res Clin Pract ; 158: 107930, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31738998

RESUMO

AIMS: Sensory loss and impaired balance are considered risk factors of incident falls. The aim of this study was to assess the relationship between degree of foot sensation and balance, risk of falls, incidence of fall-related injuries and costs in a cohort of patients with diabetes. METHODS: (Non)-neuropathic subjects participating in the Rotterdam Diabetic Foot Study were followed prospectively. Subjects underwent sensory testing of the feet (39 item Rotterdam Diabetic Foot Study Test Battery (RDF-39)); balance was assessed at the second follow-up (Brief-BESTest) as were data on incident falls. Medical records and financial data were abstracted to estimate fall-related morbidity and in-hospital costs. RESULTS: A higher RDF-39 score, cerebral artery disease, type 2 diabetes, height and age were predictors of the Brief-BESTest total score. 41/296 patients (13.9%) reported two or more falls during follow-up. Predictors for recurrent falls were a higher RDF-39 score (aOR: 1.124, p < 0.0005), male gender (aOR: 0.319, p = 0.016), age (aOR: 0.938, p = 0.003) and type 2 diabetes (aOR: 3.157, p = 0.100). Thirty-one patients used medical resources (median US$ 440.45 (IQR: 179-1162). CONCLUSIONS: Degree of sensory loss correlates significantly with an increased imbalance and risk of falls. The RDF-39 may be used as stratification tool in medical decision-making and patient information.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Diabetes Mellitus Tipo 2/complicações , Neuropatias Diabéticas/complicações , Equilíbrio Postural/fisiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
20.
J Neurosci Methods ; 174(2): 265-71, 2008 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-18721825

RESUMO

For early assessment of axonal outgrowth after trauma, the nerve is surgically exposed to enable compound nerve action potential (CNAP) recordings across the lesion site. Near-nerve neurography, with needle electrodes placed transcutaneously near the nerve, could be a minimally invasive alternative if the needle placement procedure and low reproducibility are improved. We developed ultrasound-guided near-nerve neurography, which facilitates needle placement, and assessed its potential for evaluating nerve regeneration. Measurements were performed at varying times after crush lesion of the peroneal nerve of 25 rabbits. To test if ultrasound-guided near-nerve signals could be measured prior to muscle reinnervation, they were compared with recordings of compound muscle action potentials. A comparison with conventional intra-operative CNAP recordings was made by measuring nerve signal amplitude with both techniques and by assessing reproducibility. In all cases where intra-operative signals could be measured, near-nerve signals were also detected. Compound nerve activity could be recorded after 5 weeks, whereas compound muscle activity appeared after approximately 8 weeks. Reproducibility was slightly better for near-nerve than for intra-operative recordings. We conclude that ultrasound-guided near-nerve neurography is able to assess nerve regeneration well before compound muscle activity can be detected. Its accuracy and reproducibility are similar to those of conventional intra-operative recordings.


Assuntos
Regeneração Nervosa/fisiologia , Nervo Fibular/diagnóstico por imagem , Nervo Fibular/fisiologia , Potenciais de Ação/fisiologia , Animais , Estimulação Elétrica , Masculino , Músculo Esquelético/inervação , Compressão Nervosa , Coelhos , Ultrassonografia
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