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1.
Genes (Basel) ; 15(3)2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38540432

RESUMO

In a mass fatality incident (MFI), effective preservation of tissue samples is the cornerstone for downstream DNA-based identification of victims. This is commonly achieved through freezing of tissue samples excised from bodies/fragmented remains which may be buried or stored in refrigerated containers. This may, however, not be possible depending on the nature of the MFI; in particular, during armed conflict/war where extended periods of electrical outages would be expected. The present study compared the effectiveness of long-term tissue preservation at ambient temperatures using two commercial products (non-iodized kitchen salt and a 40% alcoholic beverage) against a chemical preservative (Allprotect™ Tissue Reagent (Qiagen, Germantown, MD, USA)) and freezing at -20 °C. Bovine muscle tissue, used as a proxy for human tissue, was treated with the four preservation methods and sampled at six different time-points over a 24-month period. All four methods were able to preserve the bovine tissue, generally yielding STR-PCR (Short Tandem Repeat-Polymerase Chain Reaction) amplicons > 200 bp in size even at the end of 24 months. Gel electrophoresis, however, indicated that salt was more effective in preserving DNA integrity with high-molecular-weight DNA clearly visible as compared to the low-molecular-weight DNA smears observed in the other methods. This study also proposes a simple process for the rapid and low-cost preservation of tissue samples for long-term storage at ambient temperatures in support of post-incident victim identification efforts.


Assuntos
Incidentes com Feridos em Massa , Preservação de Tecido , Animais , Bovinos , Humanos , Temperatura , Preservação de Tecido/métodos , DNA/genética , DNA/análise , Manejo de Espécimes/métodos
2.
Otol Neurotol ; 45(3): 285-294, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38361296

RESUMO

OBJECTIVE: To compare the long-term outcomes of the linear incision technique with tissue reduction (LIT-TR) and the linear incision technique with tissue preservation (LIT-TP) for inserting bone-anchored hearing implants (BAHIs). STUDY DESIGN: Single-center retrospective cohort study. SETTING: Large general teaching hospital. PATIENTS: A total of 231 adult patients were included between August 2005 and October 2020, with a minimum follow-up time of 6 months. INTERVENTION: The test group received a BAHI using the LIT-TP (N = 147). The control group underwent surgery using the LIT-TR (N = 84). MAIN OUTCOME MEASURES: Soft tissue reactions, skin thickening, postoperative complications (e.g., wound dehiscence), and implant loss were compared between the test and control group. Furthermore, Cochlear Bone Anchored Solutions AB (Mölnlycke, Sweden) and Oticon Medical AB (Askim, Sweden) implants/abutments within the LIT-TP cohort were compared. Validated questionnaires were used to quantify patients' health-related quality of life (HRQoL). RESULTS: Significantly more cases with wound dehiscence and adverse soft tissue reactions (Holgers ≥2) were observed in the LIT-TR cohort (p < 0.001). However, the LIT-TP cohort showed significantly more cases with skin thickening (requiring treatment) within the first 2 years after implantation. There were no differences in implant loss rates, overall soft tissue reactions (Holgers >1), and overall HRQoL between the two patient groups. Significant improvement in the patients' HRQoL after implementation of a BAHI was found in both techniques. The Ponto Wide implant/abutment showed less frequent skin thickening (requiring treatment) and fewer soft tissue reactions compared with the BIA400 implant/abutment. CONCLUSION: This large-scale study demonstrates that the LIT-TP shows excellent long-term outcomes, including a low incidence of implant failure.


Assuntos
Auxiliares de Audição , Adulto , Humanos , Estudos Retrospectivos , Auxiliares de Audição/efeitos adversos , Qualidade de Vida , Audição , Complicações Pós-Operatórias/epidemiologia , Preservação de Tecido , Âncoras de Sutura , Resultado do Tratamento
3.
Am J Pathol ; 194(1): 150-164, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37827217

RESUMO

Corneal endothelial cells (CEnCs) regulate corneal hydration and maintain tissue transparency through their barrier and pump function. However, these cells exhibit limited regenerative capacity following injury. Currently, corneal transplantation is the only established therapy for restoring endothelial function, and there are no pharmacologic interventions available for restoring endothelial function. This study investigated the efficacy of the neuropeptide α-melanocyte-stimulating hormone (α-MSH) in promoting endothelial regeneration during the critical window between ocular injury and the onset of endothelial decompensation using an established murine model of injury using transcorneal freezing. Local administration of α-MSH following injury prevented corneal edema and opacity, reduced leukocyte infiltration, and limited CEnC apoptosis while promoting their proliferation. These results suggest that α-MSH has a proregenerative and cytoprotective function on CEnCs and shows promise as a therapy for the prevention and management of corneal endothelial dysfunction.


Assuntos
Córnea , Edema da Córnea , alfa-MSH , Feminino , Gravidez , Animais , Camundongos , Camundongos Endogâmicos BALB C , Humanos , Linhagem Celular , Córnea/citologia , Células Endoteliais , Edema da Córnea/tratamento farmacológico , Edema da Córnea/patologia , Preservação de Tecido , alfa-MSH/uso terapêutico , Citoproteção , Infiltração de Neutrófilos , Monócitos/metabolismo , Macrófagos/metabolismo , Cicatrização/efeitos dos fármacos
4.
Rev. bras. oftalmol ; 83: e0012, 2024. graf
Artigo em Inglês | LILACS | ID: biblio-1550774

RESUMO

ABSTRACT Objective: To analyze the morphological and functional long-term outcomes of amniotic membrane transplantation after ocular surface chemical burns. Methods: This prospective study analyzed 7 patients who suffered from severe ocular surface burn and underwent amniotic membrane transplantation from 2015 to 2020 in Hospital de Clínicas - Universidade Federal do Paraná. Results: Out of the seven patients, six (85.7%) suffered unilateral burn and one (14.3%) suffered bilateral burn. Five of them had alkali burns (71.4%), one had acid burn (14.3%) and one suffered gunpowder fireworks burn (14.3%). Mean age was 29.4 years (±standard deviation 13.3, range 14.0 to 47.0 years). Mean visual acuity at first presentation was 1.83±0.79 logMAR (0.015 decimal) and mean VA after a follow-up of 1 year was 0.85±0.70 logMAR (0.141 decimal). The visual acuity significantly improved from 1.83±0.79 to 0.85±0.70 logMAR (p<0.05). Conclusion: Amniotic membrane transplantation is an effective adjunctive treatment in the management of ocular surface chemical burns with potential to improve the final vision outcome.


RESUMO Objetivo: Analisar os resultados morfológicos e funcionais a longo prazo do transplante de membrana amniótica após queimaduras químicas da superfície ocular. Métodos: Foi realizado um estudo prospectivo com análise de sete pacientes que sofreram queimaduras graves da superfície ocular e foram submetidos a transplante de membrana amniótica no período de 2015 a 2020 no Hospital de Clínicas da Universidade Federal do Paraná. Resultados: Dos sete pacientes, seis (85,7%) sofreram queimadura unilateral e um (14,3%) sofreu queimadura bilateral. Cinco deles sofreram queimaduras por álcali (71,4%), um por ácido (14,3%) e um por pólvora de fogo de artifício (14,3%). A média de idade foi de 29,4 anos (±desvio-padrão de 13,3, intervalo de 14,0 a 47,0 anos). A acuidade visual média na primeira apresentação foi de 1,83±0,79 logMAR (0,015 decimal) e, após 1 ano de seguimento, foi de 0,85±0,70 logMAR (0,141 decimal). A acuidade visual melhorou significativamente, de 1,83±0,79 para 0,85±0,70 logMAR (p<0,05). Conclusão: O transplante de membrana amniótica é um tratamento adjuvante eficaz no manejo de queimaduras químicas da superfície ocular com potencial para melhorar a visão final.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos/métodos , Queimaduras Químicas/cirurgia , Queimaduras Oculares/cirurgia , Queimaduras Oculares/induzido quimicamente , Córnea/cirurgia , Âmnio/transplante , Preservação de Tecido , Acuidade Visual , Estudos Prospectivos , Membranas/transplante
5.
Int. j. morphol ; 41(6): 1587-1595, dic. 2023. tab
Artigo em Inglês | LILACS | ID: biblio-1528805

RESUMO

SUMMARY: Anatomy and clinical skills are taught separately to physical and occupational therapy students. Formaldehyde is the primary chemical used to embalm donors which creates a challenge in integrating clinical skills into the anatomy curriculum. This study aimed to evaluate the integration of clinical skills into anatomical education using Imperial College London- Soft Preservation (ICL-SP) and formaldehyde embalming through the evaluation of student perceived learning and confidence. Students were invited to complete a survey after dissecting an ICL-SP and formaldehyde embalmed donors and perform clinical tests. It was easier to dissect and identify neurovascular structures on ICL-SP donors compared to formaldehyde. Clinical tests, like measuring range of motion and ligament tests were also more realistic on ICL-SP donors. The integration of clinical skills in the anatomical curriculum increased student perceived understanding of associated anatomy (p < 0.001), gave better understanding of how anatomy is important to their professions (p < 0.001) and increased motivation to learn anatomy (p < 0.001). The integration of clinical skills into anatomical education can facilitate student learning with higher confidence performing clinical skills and is complemented by the utilization of the new ICL-SP methodology instead of the traditional formaldehyde preservation.


Las habilidades anatómicas y clínicas se enseñan por separado a los estudiantes de terapia física y ocupacional. El formaldehído es el químico principal que se usa para embalsamar a los donantes, lo que crea un desafío para integrar las habilidades clínicas en el plan de estudios de anatomía. Este estudio tuvo como objetivo evaluar la integración de habilidades clínicas en la educación anatómica utilizando Imperial College London-Soft Preservation (ICL-SP) y embalsamamiento de formaldehído a través de la evaluación del aprendizaje y la confianza percibidos por los estudiantes. Se invitó a los estudiantes a completar una encuesta después de diseccionar un ICL-SP y donantes embalsamados formolizados y realizar pruebas clínicas. Fue más fácil diseccionar e identificar estructuras neurovasculares en donantes ICL-SP en comparación con los fijados en formaldehído. Las pruebas clínicas, como la medición del rango de movimiento y las pruebas de ligamentos, también fueron más realistas en los donantes de ICL-SP. La integración de habilidades clínicas en el plan de estudios anatómico aumentó la comprensión percibida por los estudiantes de anatomía asociada (p < 0,001), dio una mejor comprensión de cómo la anatomía es importante para sus profesiones (p < 0,001) y aumentó la motivación para aprender anatomía (p < 0,001). La integración de las habilidades clínicas en la educación anatómica puede facilitar el aprendizaje de los estudiantes con mayor confianza en el desempeño de las habilidades clínicas y se complementa con la utilización de la nueva metodología ICL-SP en lugar de la conservación tradicional con formaldehído.


Assuntos
Humanos , Estudantes/psicologia , Preservação de Tecido/métodos , Anatomia/educação , Cadáver , Inquéritos e Questionários , Terapia Ocupacional , Modalidades de Fisioterapia , Competência Clínica , Currículo , Dissecação , Embalsamamento , Formaldeído
6.
Int. j. morphol ; 41(4): 1004-1008, ago. 2023. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1514328

RESUMO

SUMMARY: For the purposes of teaching anatomy, the use of cadaver preparations is considered the most efficient way of ensuring that students retain knowledge. Nevertheless, in Ecuador the use of animal specimens in universities must comply with the internationally accepted principles of replacement, reduction and refinement (3Rs). Plastination is an alternative technique which allows organs to be conserved in the long term and complies with the 3Rs. The object of the present work was to use cold-temperature silicone plastination with Biodur® products to obtain long-lasting, easy-to-handle canine organs for use as tools for the teaching of animal anatomy. Six canine cadavers were obtained from local animal protection charities. The hearts, brains and kidneys of the cadavers were dissected and fixed with formaldehyde 10 %. They were then dehydrated with acetone at -20 °C. The specimens were impregnated with Biodur® S10:S3 (-20 °C) and finally cured with Biodur® S6. We plastinated six hearts, twelve kidneys, four brains and one encephalic slice of canine. The application of cold-temperature plastination to canine organs followed the parameters established for the conventional protocol, enabling us to obtain organs of brilliant appearance, free of odours, in which the anatomical form was preserved. Thus the technique helped us to comply with the 3Rs, as we obtained easy-to-handle teaching models to replace fresh or formaldehyde-fixed samples for the teaching-learning of the canine anatomy.


En la enseñanza de la Anatomía, el uso de preparaciones cadavéricas se considera el método que permite a los estudiantes retener el conocimiento de una forma más eficiente. No obstante, en Ecuador, el uso de especímenes animales en las universidades se debe realizar bajo el principio internacional de reemplazo, reducción y refinamiento (3Rs). La técnica de plastinación es una técnica alternativa que permite preservar órganos a largo plazo y que se adapta al principio de las 3Rs. El objetivo del trabajo fue utilizar la técnica de plastinación en silicona al frío con productos Biodur® para obtener órganos caninos duraderos y manejables útiles como herramienta para la enseñanza de la anatomía animal. Se obtuvieron seis cadáveres de caninos de fundaciones locales para la protección animal. Se realizaron disecciones de corazones, cerebros y riñones de los cadáveres caninos. Los órganos se fijaron con formalina al 10 %. A continuación, se llevó a cabo la deshidratación con acetona a -20 °C. Los especímenes fueron impregnados con S10:S3 Biodur® (-20 °C) y al final fueron curados con Biodur® S6. Se lograron plastinar seis corazones, doce riñones, cinco encéfalos y un tallo encefálico de canino. La técnica de plastinación al frío utilizada para obtener órganos de canino conservó los parámetros empleados en el protocolo convencional y permitió obtener órganos que presentaron aspecto brillante, ausencia de olores y mantuvieron la forma anatómica. Por lo que, la técnica facilitó cumplir con el principio de las 3Rs al obtenerse modelos didácticos fáciles de manipular que pueden reemplazar muestras frescas o formolizadas en el proceso de enseñanza-aprendizaje de la anatomía del canino.


Assuntos
Animais , Cães , Preservação de Órgãos/métodos , Criopreservação , Plastinação , Anatomia Veterinária/educação , Silicones , Preservação de Tecido/métodos , Temperatura Baixa , Cérebro/anatomia & histologia , Coração/anatomia & histologia , Rim/anatomia & histologia
7.
Lab Invest ; 103(9): 100198, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37321542

RESUMO

Formalin, a common laboratory fixative, is a type 1 carcinogen; a biohazard with risks, environmental, disposal, and legal costs; and a chemical modifier of protein epitopes in tissues. A less-toxic tissue preservation method is therefore badly needed. We have developed a novel tissue preservation medium, Amber, composed of low-potassium dextran glucose, 10% honey, and 1% coconut oil. This study investigates Amber as compared with formalin with respect to the following aspects: (1) histologic preservation, (2) epitope integrity with immunohistochemistry (IHC) and immunofluorescence (IF), and (3) integrity of tissue RNA. Rat and human lung, liver, kidney, and heart tissues were collected and stored for 24 hours at 4 °C in Amber or formalin. The tissues were evaluated with hematoxylin and eosin; IHC: thyroid transcription factor, muscle-specific actin, hepatocyte-specific antigen, and common acute lymphoblastic leukemia antigen; and IF: VE-cadherin, vimentin, and muscle-specific actin. RNA quality upon extraction was also assessed. Amber demonstrated superior and/or noninferior performance in rat and human tissue evaluation with respect to standard techniques of histology, IHC, IF, and extracted RNA quality. Amber maintains high-quality morphology without compromising the ability to perform IHC and nucleic acid extraction. As such, Amber could be a safer and superior substitute to formalin for clinical tissue preservation for contemporary pathological examination.


Assuntos
Actinas , Formaldeído , Ratos , Humanos , Animais , Âmbar , Fixadores , Preservação de Tecido/métodos , RNA , Antígenos , Fixação de Tecidos/métodos
8.
Compr Physiol ; 13(3): 4719-4765, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37358515

RESUMO

Heart transplantation (HT) is one of the prodigious achievements in modern medicine and remains the cornerstone in the treatment of patients with advanced heart failure. Advances in surgical techniques, immunosuppression, organ preservation, infection control, and allograft surveillance have improved short- and long-term outcomes thereby contributing to greater clinical success of HT. However, prolonged allograft and patient survival following HT are still largely restricted by the development of late complications, including allograft rejection, infection, cardiac allograft vasculopathy (CAV), and malignancy. The introduction of mTOR inhibitors early after HT has demonstrated multiple protective effects against CAV progression, renal dysfunction, and tumorigenesis. Therefore, several HT programs increasingly use mTOR inhibitors with partial or complete withdrawal of calcineurin inhibitor (CNI) in stable HT patients to reduce complications risk and improve long-term outcomes. Furthermore, despite a substantial improvement in exercise capacity and health-related quality of life after HT as compared to advanced heart failure patients, most HT recipients remain with a 30% to 50% lower peak oxygen consumption (Vo 2 ) than that of age-matched healthy subjects. Several factors, including alterations in central hemodynamics, HT-related complications and alterations in the musculoskeletal system, and peripheral physiological abnormalities, presumably contribute to the reduced exercise capacity following HT. Cardiac denervation and subsequent loss of sympathetic and parasympathetic regulation are responsible for various physiological alterations in the cardiovascular system, which contributes to restricted exercise tolerance. Restoration of cardiac innervation may improve exercise capacity and quality of life, but the reinnervation process is only partial even several years after HT. Multiple studies have shown that aerobic and strengthening exercise interventions improve exercise capacity by increasing maximal heart rate, chronotropic response, and peak Vo 2 after HT. Novel exercise modalities, such as high-intensity interval training (HIT), have been proven as safe and effective for further improvement in exercise capacity, including among de novo HT recipients. Further developments have recently emerged, including donor heart preservation techniques, noninvasive CAV and rejection surveillance methods, and improvements in immunosuppressive therapies, all aiming at increasing donor availability and improving late survival after HT. © 2023 American Physiological Society. Compr Physiol 13:4719-4765, 2023.


Assuntos
Transplante de Coração , Coração , Humanos , Insuficiência Cardíaca/cirurgia , Cardiopatias/epidemiologia , Rejeição de Enxerto/epidemiologia , Inibidores de MTOR/uso terapêutico , Qualidade de Vida , Tolerância ao Exercício , Coração/inervação , Coração/fisiologia , Imunossupressores/uso terapêutico , Preservação de Tecido , Disfunção Primária do Enxerto/epidemiologia
9.
Methods Cell Biol ; 176: 217-234, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37164539

RESUMO

Autophagy is an intracellular catabolic pathway that allows proteins, organelles, and pathogens to be recycled. Thus, it is crucial to maintain cell homeostasis, especially important in post-mitotic cells as neurons that cannot dilute cellular damage through mitosis. In the last decade, autophagy has been connected to the primary cilium (PC), a small organelle that acts as a sensory hub and is present in most cell types, including astrocytes and neurons. In this chapter, we briefly describe the state-of-the-art of the interplay between autophagy, PC, and its implications for the brain, in healthy and pathophysiological conditions. Deregulations in autophagy can be monitored by numerous assays, both in vivo and in vitro, and so do changes in PC length/number. Here, we relate a practical and user-friendly description of immunofluorescence methods to study autophagy and PC changes in brain slices, including the tissue preparation, confocal microscopy, image analysis, and deconvolution process.


Assuntos
Autofagia , Encéfalo , Cílios , Imunofluorescência , Encéfalo/citologia , Cílios/fisiologia , Imunofluorescência/métodos , Microscopia Confocal , Humanos , Animais , Processamento de Imagem Assistida por Computador , Preservação de Tecido
10.
J Clin Periodontol ; 50(7): 1010-1020, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37052357

RESUMO

AIM: This randomized controlled trial aimed to investigate the efficacy of soft-tissue augmentation (STA) with a subepithelial connective tissue graft (SCTG) or an acellular dermal matrix (ADM) on reducing tissue alterations at an immediate implant site. MATERIALS AND METHODS: This trial had three groups: (i) immediate implant with SCTG (ICT group); (ii) immediate implant with ADM (IAD group); (iii) immediate implant without STA (control group). Forty-six patients were randomly assigned to each group. Implants were placed at the maxillary anterior or premolar areas and restored after the 6-month visit. Clinical outcomes, including buccal soft-tissue contour, peri-implant mucosal level, soft-tissue thickness and keratinized tissue width, were measured at baseline and at 3-, 6- and 12-month follow-up visits. Radiographic bone levels were measured at baseline and at 6- and 12-month follow-up visits. Patient-reported outcomes were also collected. RESULTS: STA procedures increased peri-implant mucosal thickness and maintained buccal soft-tissue contours. Compared to the control group, STA groups did not prevent peri-implant mucosal recession or interproximal bone resorption. Generally, no significant differences in clinical outcomes were detected between the ICT and IAD groups. Most patients were highly satisfied with the immediate implant procedure and outcomes without significant differences between groups. CONCLUSIONS: STA at immediate implant sites enhanced soft-tissue thickness and maintained soft-tissue contours but did not prevent peri-implant mucosal recession or interproximal bone resorption. Long-term follow-up should be performed since these results were reported for only up to 1 year.


Assuntos
Reabsorção Óssea , Implantes Dentários para Um Único Dente , Carga Imediata em Implante Dentário , Humanos , Tecido Conjuntivo/transplante , Resultado do Tratamento , Maxila/cirurgia , Preservação de Tecido
11.
Orthop Traumatol Surg Res ; 109(7): 103608, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36958622

RESUMO

INTRODUCTION: The aim of this study is to compare the preservation of bursal tissue and microfracture techniques and to examine the effectiveness of the combination of the two methods in rotator cuff tear healing in the rat shoulder. HYPOTHESIS: Bursal tissue preservation combined with microfracture is more effective in the rotator cuff repair. MATERIALS AND METHODS: Twenty-three male Sprague-Dawley rats were randomly divided into two groups. The bursal tissue was preserved in group 1 (n=11) and excised in group 2 (n=12). Groups were categorized into subgroups as L (left) and R (right) based on the shoulder side receiving microfracture (L received microfracture, R did not). Histopathological examination was performed using modified Bonar Score System. RESULTS: Cell morphology grades of group 1 were lower than group 2 (p<0.05). In terms of collagen measurements, the grade of group 1L (bursa preservation+microfracture) was lower than groups 1R, 2L, and 2R, and the grade of group 1R was lower than groups 2L and 2R. Cellularity grades of group 2 were higher than group 1 (p<0.05). Extracellular matrix grades of group 1 were lower than group 2 (p<0.05). The overall grades were lower in group 1 than in group 2 (p<0.05). DISCUSSION: Combined treatment of bursal tissue preservation and microfracture was the most efficient method as determined by healing findings in histopathological specimens. Preservation of bursal tissue was a more effective option in tendon healing than performing only microfracture. LEVEL OF PROOF: II, animal research.


Assuntos
Fraturas de Estresse , Lesões do Manguito Rotador , Masculino , Animais , Ratos , Ombro , Manguito Rotador/cirurgia , Ratos Sprague-Dawley , Lesões do Manguito Rotador/cirurgia , Lesões do Manguito Rotador/patologia , Preservação de Tecido
12.
Commun Biol ; 6(1): 220, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36828843

RESUMO

Successful organ or tissue long-term preservation would revolutionize biomedicine. Cartilage cryopreservation enables prolonged shelf life of articular cartilage, posing the prospect to broaden the implementation of promising osteochondral allograft (OCA) transplantation for cartilage repair. However, cryopreserved large sized cartilage cannot be successfully warmed with the conventional convection warming approach due to its limited warming rate, blocking its clinical potential. Here, we develope a nanowarming and ice-free cryopreservation method for large sized, intact articular cartilage preservation. Our method achieves a heating rate of 76.8 °C min-1, over one order of magnitude higher than convection warming (4.8 °C min-1). Using systematic cell and tissue level tests, we demonstrate the superior performance of our method in preserving large cartilage. A depth-dependent preservation manner is also observed and recapitulated through magnetic resonance imaging and computational modeling. Finally, we show that the delivery of nanoparticles to the OCA bone side could be a feasible direction for further optimization of our method. This study pioneers the application of nanowarming and ice-free cryopreservation for large articular cartilage and provides valuable insights for future technique development, paving the way for clinical applications of cryopreserved cartilage.


Assuntos
Cartilagem Articular , Suínos , Animais , Criopreservação/métodos , Preservação de Tecido , Imageamento por Ressonância Magnética
13.
J Knee Surg ; 36(4): 450-455, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34600436

RESUMO

The indications for fresh osteochondral allograft continue to increase. As a result, variations in graft processing and preservation methods have emerged. An understanding of these techniques is important when evaluating the optimal protocol for processing fresh osteochondral allografts prior to surgical implantation. The aim of this study is to review the literature and understand various tissue processing protocols of four leading tissue banks in the United States. Donor procurement, serological and microbiological testing, and storage procedures were compared among companies of interest. Similarities between the major tissue banks include donor screening, aseptic processing, and testing for microorganisms. Variability exists between these companies with relation to choice of storage media, antibiotic usage, storage temperature, and graft expiration dates. Potential exists for increased chondrocyte viability and lengthened time-to-expiration of the graft through a protocol of delicate tissue handling, proper choice of storage medium, adding hormones and growth factors like insulin growth factor-1 (IGF-1) to serum-free nutrient media, and storing these grafts closer to physiologic temperatures.


Assuntos
Cartilagem Articular , Preservação de Tecido , Humanos , Preservação de Tecido/métodos , Sobrevivência Celular , Transplante Homólogo/métodos , Condrócitos/transplante , Aloenxertos , Cartilagem Articular/cirurgia , Transplante Ósseo
14.
Proc Biol Sci ; 289(1986): 20221623, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36321492

RESUMO

Exoskeletal dwelling tubes are widespread among extant animals and early fossil assemblages. Exceptional fossils from the Cambrian reveal independent origins of tube dwelling by several clades including cnidarians, lophophorates, annelids, scalidophorans, panarthropods and ambulacrarians. However, most fossil tubes lack preservation of soft parts, making it difficult to understand their affinities and evolutionary significance. Gangtoucunia aspera (Wulongqing Formation, Cambrian Stage 4) was an annulated, gradually expanding phosphatic tube, with occasional attachments of multiple, smaller juveniles and has previously been interpreted as the dwelling tube of a 'worm' (e.g. a scalidophoran), lophophorate or problematicum. Here, we report the first soft tissues from Gangtoucunia that reveal a smooth body with circumoral tentacles and a blind, spacious gut that is partitioned by septa. This is consistent with cnidarian polyps and phylogenetic analysis resolves Gangtoucunia as a total group medusozoan. The tube of Gangtoucunia is phenotypically similar to problematic annulated tubular fossils (e.g. Sphenothallus, Byronia, hyolithelminths), which have been compared to both cnidarians and annelids, and are among the oldest assemblages of skeletal fossils. The cnidarian characters of G. aspera suggest that these early tubular taxa are best interpreted as cnidarians rather than sessile bilaterians in the absence of contrary soft tissue evidence.


Assuntos
Cnidários , Animais , Filogenia , Fosfatos , Fósseis , Evolução Biológica , Preservação de Tecido
15.
PLoS One ; 17(10): e0275240, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36223345

RESUMO

Removal or protection from biostratinomic agents of decomposition, such as predators and scavengers, is widely seen as a requirement for high-quality preservation of soft tissues in the fossil record. In this context, extremely rapid burial is an oft-cited mechanism for shielding remains from degradation, but not all fossils fit nicely into this paradigm. Dinosaurian mummies in particular seemingly require two mutually exclusive taphonomic processes to preserve under that framework: desiccation and rapid burial. Here we present a recently prepared Edmontosaurus mummy that reveals an alternate fossilization pathway for resistant soft tissues (e.g., skin and nails). While the skin on this specimen is well-preserved in three dimensions and contains biomarkers, it is deflated and marked by the first documented examples of injuries consistent with carnivore activity on dinosaurian soft tissue during the perimortem interval. Incomplete scavenging of the carcass provided a route for the gases, fluids, and microbes associated with decomposition to escape, allowing more durable soft tissues to persist through the weeks to months required for desiccation prior to entombment and fossilization. This pathway is consistent with actualistic observations and explains why dinosaurian skin, while rare, is more commonly preserved than expected if extreme circumstances were required for its preservation. More broadly, our assumptions guide specimen collection and research, and the presence of soft tissues and biomolecules in fossils that demonstrably were not rapidly buried, such as this mummy, suggests that such types of evidence may be substantially more common than previously assumed.


Assuntos
Múmias , Fósseis , Gases , Preservação Biológica , Preservação de Tecido
16.
Biopreserv Biobank ; 20(5): 436-445, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36301140

RESUMO

There is growing interest in proteomic analyses of tissue biopsies to reveal pathophysiology and identify biomarkers. The current gold standard for collecting tissue biopsies for preserving the proteome and post-translational modifications is flash freezing in liquid nitrogen (LN2). However, in many clinical settings, this is not an option due to unavailability of LN2 nor trained personnel for rapid biospecimen processing. To address this need, we developed a proof-of-concept quick-freeze prototype device to rapidly freeze biospecimens at the point-of-care to preserve the phosphoproteome without the need for LN2. Our objectives were to develop the device, demonstrate the ease of use, confirm the ability to ship through existing cold chain logistics, and evaluate the cooling performance (i.e., cool a tissue sample to <0°C in <60 seconds, below -8°C in <120 seconds, and maintain temperature <0°C for >60 minutes) in the context of preserving the proteome in a tissue biospecimen. To demonstrate feasibility, the performance of the prototype was benchmarked against flash freezing in LN2 using a murine melanoma patient-derived xenograft model subjected to total body irradiation to elicit phosphosignaling in the DNA damage response network. Tumors were harvested and quadrisected, with two parts of the tumor being snap frozen in LN2, and the remaining two parts being rapidly cooled in the prototype quick-freeze biospecimen containers. Phosphoproteins were profiled by liquid chromatography tandem mass spectrometry and quantified by targeted multiple reaction monitoring MS. Overall, the phosphoproteome was equivalent in biospecimens processed using the quick-freeze containers to those using the LN2 gold standard, although the measurements of a subset of phosphopeptides in the device-frozen specimens were more variable than LN2-frozen specimens. The prototype device forms the framework for development of a commercial device that will improve tissue biopsy preservation for measurement of important phosphosignaling molecules.


Assuntos
Proteoma , Proteômica , Humanos , Camundongos , Animais , Proteoma/análise , Proteoma/química , Congelamento , Preservação de Tecido , Biópsia
17.
Indian J Ophthalmol ; 70(8): 2946-2949, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35918950

RESUMO

Purpose: To evaluate the role of McCarey-Kaufman (MK) medium in maintaining the integrity of donor corneal epithelium. Methods: Nineteen corneal buttons were harvested and stored in MK media at 2°C-8°C for four days. Serial photographs were done every day till the 3rd day, and images were then analyzed with ImageJ software (LOCI, University of Wisconsin, USA). The area of exposure and epithelial defect (ED) was calculated every day for each corneal button. Results: The average age of the donors was 56.5 ± 22.7 years and mean time from death to preservation of the corneal buttons was 7.7 ± 3.1 hours. The average corneal area was 145.6 ± 18.8 mm2. The total mean area of exposure was 3.6 ± 4.8, 7.2 ± 9.2, and 9.0 ± 11.9 mm2, and ED was 1.7 ± 4.6, 2.8 ± 5.3, and 3.3 ± 5.9 mm2 on days 1, 2, and 3, respectively. The percentage of increase in the area of exposure and ED in MK media was 3.71% and 1.1% from day 1 to day 3, respectively. Six out of 19 corneal buttons (31.57%) were utilized for keratoplasties, of which two were utilized in house and four were distributed outside. Of the two utilized corneas, none had epithelial defect on postoperative day 1. Rest 13 corneas were either used for training and research purposes, stored in glycerol media, or discarded. Conclusion: Since the percentage change in area of exposure/ED is not much at the end of day 3, corneas stored in MK media can be safely used even after three days of storage. Hence, MK medium serves as an excellent medium in maintaining the integrity of donor corneal epithelium.


Assuntos
Transplante de Córnea , Epitélio Corneano , Adulto , Idoso , Córnea/cirurgia , Humanos , Pessoa de Meia-Idade , Preservação de Órgãos/métodos , Compostos Orgânicos , Doadores de Tecidos , Preservação de Tecido/métodos
18.
Ann Biomed Eng ; 50(8): 978-990, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35648279

RESUMO

Oxygenated machine perfusion of human organs has been shown to improve both preservation quality and time duration when compared to the current gold standard: static cold storage. However, existing machine perfusion devices designed for preservation and transportation of transplantable organs are too complicated and organ-specific to merit use as a solution for all organs. This work presents a novel, portable, and nonelectronic device potentially capable of delivering oxygenated machine perfusion to a variety of organs. An innovative pneumatic circuit system regulates a compressed oxygen source that cyclically inflates and deflates silicone tubes, which function as both the oxygenator and perfusion pump. Different combinations of silicone tubes in single or parallel configurations, with lengths ranging from 1.5 to 15.2 m, were evaluated at varying oxygen pressures from 27.6 to 110.3 kPa. The silicone tubes in parallel configurations produced higher peak perfusion pressures (70% increase), mean flow rates (102% increase), and oxygenation rates (268% increase) than the single silicone tubes that had equivalent total lengths. While pumping against a vascular resistance element that mimicked a kidney, the device achieved perfusion pressures (8.4-131.6 mmHg), flow rates (2.0-40.2 mL min-1), and oxygenation rates (up to 388 µmol min-1) that are consistent with values used in previous kidney preservation studies. The nonelectronic device achieved those perfusion parameters using 4.4 L min-1 of oxygen to operate. These results demonstrate that oxygenated machine perfusion can be successfully achieved without any electronic components.


Assuntos
Preservação de Órgãos , Preservação de Tecido , Humanos , Preservação de Órgãos/métodos , Oxigênio , Perfusão/métodos , Silicones
19.
Sci Rep ; 12(1): 8292, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739131

RESUMO

Although soft tissues of coleoid cephalopods record key evolutionary adaptations, they are rarely preserved in the fossil record. This prevents meaningful comparative analyses between extant and fossil forms, as well as the development of a relative timescale for morphological innovations. However, unique 3-D soft tissue preservation of Vampyronassa rhodanica (Vampyromorpha) from the Jurassic Lagerstätte of La Voulte-sur-Rhône (Ardèche, France) provides unparalleled opportunities for the observation of these tissues in the oldest likely relative of extant Vampyroteuthis infernalis. Synchrotron X-ray microtomography and reconstruction of V. rhodanica allowed, for the first time, a high-resolution re-examination of external and internal morphology, and comparison with other fossil and extant species, including V. infernalis. The new data obtained demonstrate that some key V. infernalis characters, such as its unique type of sucker attachment, were already present in Jurassic taxa. Nonetheless, compared with the extant form, which is considered to be an opportunistic detritivore and zooplanktivore, many characters in V. rhodanica indicate a pelagic predatory lifestyle. The contrast in trophic niches between the two taxa is consistent with the hypothesis that these forms diversified in continental shelf environments prior to the appearance of adaptations in the Oligocene leading to their modern deep-sea mode of life.


Assuntos
Fósseis , Octopodiformes , Animais , Evolução Biológica , Filogenia , Preservação Biológica , Preservação de Tecido , Microtomografia por Raio-X
20.
Sci Rep ; 12(1): 10122, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710834

RESUMO

The preservation of soft tissue in the fossil record is mostly due to the replacement of organic structures by minerals (e.g. calcite, aragonite or apatite) called pseudomorphs. In rare cases soft tissues were preserved by pyrite. We assume that adipocere, as the shaping component, might be a preliminary stage in the pyritisation of soft tissues under anaerobic conditions. Using high-performance liquid chromatography coupled to ultraviolet and mass spectrometric detection (HPLC-UV/MS) and confocal Raman spectroscopy (CRS) we were able to demonstrate the transformation of the hepatopancreas (digestive gland) of the crayfish Cambarellus diminutus [Hobbs 1945] into adipocere within only 9 days, just inside a biofilm. Microorganisms (bacteria and fungi) which were responsible for the biofilm (Sphaerotilus [Kutzig 1833] and Pluteus [Fries 1857]) and maybe the adipocere formation (Clostridium [Prazmowski 1880]) were detected by 16S rRNA gene amplicon sequencing. Furthermore, micro-computed tomography (µ-CT) analyses revealed a precipitation of calcite and further showed that in animals with biofilm formation calcite precipitates in finer grained crystals than in individuals without biofilm formation, and that the precipitates were denser and replicated the structures of the cuticles better than the coarse precipitates.


Assuntos
Biofilmes , Mudanças Depois da Morte , Animais , Carbonato de Cálcio , RNA Ribossômico 16S/genética , Preservação de Tecido , Microtomografia por Raio-X
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