The Effect of High-Mobility Group Box 1 in Rat Steatotic and Nonsteatotic Liver Transplantation From Donors After Brain Death.

High-mobility group box 1 (HMGB1) has been described in different inflammatory disorders, and the deleterious effects of brain death (BD) may counteract the protection conferred by ischemic preconditioning (IP), the only surgical strategy that is being applied in clinical liver transplantation. Our study examined how HMGB1 may affect preconditioned and unpreconditioned steatotic and nonsteatotic liver grafts from donors after BD (DBDs) for transplantation. HMGB1 was pharmacologically modulated in liver grafts from DBDs, and HMGB1-underlying mechanisms were characterized. We found that BD decreased HMGB1 in preconditioned and unpreconditioned livers and was associated with inflammation and damage. Exogenous HMGB1 in DBDs activates phosphoinositide-3-kinase and Akt and reduces hepatic inflammation and damage, increasing the survival of recipients. Combination of IP and exogenous HMGB1 shows additional benefits compared with HMGB1 alone. This study provides new mechanistic insights into the pathophysiology of BD-derived liver graft damage and contributes to the development of novel and efficient strategies to ultimately improve liver graft quality.

Tauroursodeoxycholic acid affects PPARγ and TLR4 in Steatotic liver transplantation.

Numerous steatotic livers are discarded for transplantation because of their poor tolerance to ischemia-reperfusion (I/R). We examined whether tauroursodeoxycholic acid (TUDCA), a known inhibitor of endoplasmic reticulum (ER) stress, protects steatotic and nonsteatotic liver grafts preserved during 6 h in University of Wisconsin (UW) solution and transplanted. The protective mechanisms of TUDCA were also examined. Neither unfolded protein response (UPR) induction nor ER stress was evidenced in steatotic and nonsteatotic liver grafts after 6 h in UW preservation solution. TUDCA only protected steatotic livers grafts and did so through a mechanism independent of ER stress. It reduced proliferator-activated receptor-γ (PPARγ) and damage. When PPARγ was activated, TUDCA did not reduce damage. TUDCA, which inhibited PPARγ, and the PPARγ antagonist treatment up-regulated toll-like receptor 4 (TLR4), specifically the TIR domain-containing adaptor inducing IFNß (TRIF) pathway. TLR4 agonist treatment reduced damage in steatotic liver grafts. When TLR4 action was inhibited, PPARγ antagonists did not protect steatotic liver grafts. In conclusion, TUDCA reduced PPARγ and this in turn up-regulated the TLR4 pathway, thus protecting steatotic liver grafts. TLR4 activating-based strategies could reduce the inherent risk of steatotic liver failure after transplantation.

The current state of knowledge of hepatic ischemia-reperfusion injury based on its study in experimental models.

The present review focuses on the numerous experimental models used to study the complexity of hepatic ischemia/reperfusion (I/R) injury. Although experimental models of hepatic I/R injury represent a compromise between the clinical reality and experimental simplification, the clinical transfer of experimental results is problematic because of anatomical and physiological differences and the inevitable simplification of experimental work. In this review, the strengths and limitations of the various models of hepatic I/R are discussed. Several strategies to protect the liver from I/R injury have been developed in animal models and, some of these, might find their way into clinical practice. We also attempt to highlight the fact that the mechanisms responsible for hepatic I/R injury depend on the experimental model used, and therefore the therapeutic strategies also differ according to the model used. Thus, the choice of model must therefore be adapted to the clinical question being answered.

Trichoderma: biological control efficiency and perspectives for the Brazilian Midwest states and Tocantins.

Brazil is one of the world leaders in the agribusiness sector tending to directly influence a growing dependence on imported inputs, specifically synthetic agrochemicals. At the state level, in 2013, Tocantins stood out in first place in the ranking of agrochemical consumers, however, these products can cause several problems, such as poisoning to humans, environmental contamination, and increased resistance to phytopathogens. Biological control is an alternative to the use of agrochemicals towards eliminating pests naturally by using living organisms called Biological Control Agents (BCA). Currently, fungi of the Trichoderma genus are some of the most used organisms in biological pest control for their relevant characteristics that favor them in terms of survival in the environment, such as high capacity to adapt to ecological conditions, potential to colonize the rhizosphere of plants, mycoparasitism, production of volatile and non-volatile metabolites. In addition, it works on plant growth and productivity. In general, the use of Trichoderma favors the control of soil pathogens, such as Rhizoctonia, Pythium, Sclerotinia, and nematodes. Thus, this review aims to demonstrate the importance of using Trichoderma in biological control, as well as to present an overview and perspectives of research developed by respondents in the Brazilian Midwest region and Tocantins state.

Avian hosts of Ixodes pacificus (Acari: Ixodidae) and the detection of Borrelia burgdorferi in larvae feeding on the Oregon junco.

Larval and nymphal western blacklegged tick, Ixodes pacificus Cooley & Kohls (Acari: Ixodidae), were collected from birds, rodents, and lizards at Quail Ridge Reserve located in Napa County in northwestern California. Species from three vertebrate classes were sampled simultaneously from two transects during two consecutive spring seasons. Feeding larval and nymphal ticks were removed and preserved for counting, examination and testing for the presence of Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner. Mean infestations with I. pacificus subadults on lizards were 10.0, on birds 2.9, and on rodents 1.3. I. pacificus larvae (204) collected from 10 avian species and (215) collected from two rodent species were tested for the presence of B. burgdorferi s.s. via real-time polymerase chain reaction. Three B. burgdorferi-infected larvae were taken from two Junco hyemalis and two infected larvae from one Neotoma fuscipes Baird. This is the detection of B. burgdorferi ss in an Ixodes pacificus larvae feeding on a Junco hyemalis L., [corrected] in western North America.

Lethal Fascioliasis in Capybaras ( Hydrochoerus hydrochaeris) in Brazil.

The liver fluke Fasciola hepatica (Trematoda: Fasciolidae) causes fascioliasis, which affects mostly domestic ruminants and humans worldwide. This parasite has an Old World origin and was introduced into the New World by European colonizers. Capybara ( Hydrochoerus hydrochaeris) is the largest living rodent species, with adults weighing over 60 kg. We report a fascioliasis outbreak caused by F. hepatica that reduced a capybara group from 21 to 2 animals within a 9-mo period. Animal infection and associated lesions were confirmed by postmortem examinations that revealed extensive liver damage associated with the presence of large number of adult and immature forms of F. hepatica. Both macroscopic and microscopic alterations in the liver were compatible with acute fascioliasis, which is characterized by a large parasite burden in the liver. Taxonomic identification of flukes collected from capybara livers were confirmed by molecular methods, which generated a mitochondrial NADH dehydrogenase I (NDI) gene partial sequence that was 100% identical to a F. hepatica NDI sequence from the United Kingdom. This is the first report of deleterious effects caused by F. hepatica in capybaras, highlighting the potential harm caused by this exotic parasite in the capybara.

Brain death and marginal grafts in liver transplantation.

It is well known that most organs for transplantation are currently procured from brain-dead donors; however, the presence of brain death is an important risk factor in liver transplantation. In addition, one of the mechanisms to avoid the shortage of liver grafts for transplant is the use of marginal livers, which may show higher risk of primary non-function or initial poor function. To our knowledge, very few reviews have focused in the field of liver transplantation using brain-dead donors; moreover, reviews that focused on both brain death and marginal grafts in liver transplantation, both being key risk factors in clinical practice, have not been published elsewhere. The present review aims to describe the recent findings and the state-of-the-art knowledge regarding the pathophysiological changes occurring during brain death, their effects on marginal liver grafts and summarize the more controversial topics of this pathology. We also review the therapeutic strategies designed to date to reduce the detrimental effects of brain death in both marginal and optimal livers, attempting to explain why such strategies have not solved the clinical problem of liver transplantation.

Primary gastric rupture in 20 horses from Midwestern Brazil: case report / Ruptura gástrica primária em 20 equinos no Centro-Oeste do Brasil: relato de caso

An 11-year (2007-2018) survey of epidemiological, clinical and pathological findings of horses with primary gastric rupture (PGR) was conducted. Twenty horses presented PGR, nine (45%) horses were clinically evaluated, eleven (55%) were sent dead, and all animals were necropsied. PGR contributed to a prevalence of 0.31% (9/2,868) of all equid attendances, 1.83% (9/491) of colic cases, and 4.1% (20/487) of all equid necropsies. Highly fermentable feed (n=7), gastric impaction (n=4), and perforating gastric ulcer (n=1) were the main causes of PGR; whilst eight horses presented idiopathic gastric rupture. Clinically evaluated horses were tachycardic, tachypneic, febrile, dehydrated, with increased abdominal tension, abnormal mucous membranes and reduced to absent intestinal borborygmi. Improper dietary management, such as the ingestion of low-quality roughage and highly fermentable feedstuffs were detected as the main factors associated with PGR in Midwestern Brazil. It is important to raise awareness in horse owners about proper feed management to minimize PGR.(AU)

Foi realizado um levantamento de 11 anos (2007-2018) dos achados epidemiológicos, clínicos e patológicos de equinos com ruptura gástrica primária (RGP). Vinte equinos apresentaram RGP, dos quais nove (45%) foram avaliados clinicamente e 11 (55%) foram enviados mortos, sendo todos os animais necropsiados. A RGP contribuiu com prevalência de 0,31% de todos os atendimentos de equídeos (9/2.868), 1,83% (9/491) dos casos de cólica, e 4,1% (20/487) das necropsias em equídeos. Alimentos altamente fermentáveis (n=7), compactação gástrica (n=4) e perfuração de úlcera gástrica (n=1) foram as principais causas de RGP, enquanto oito equinos tiveram ruptura gástrica idiopática. Os equinos avaliados clinicamente apresentaram-se taquicárdicos, taquipneicos, febris, desidratados, com mucosas anormais, aumento da tensão abdominal e motilidade intestinal reduzida. O manejo inadequado da dieta, como a ingestão de forragens de baixa qualidade e alimentos altamente fermentáveis, foi o principal fator de risco associado à RGP no Centro-Oeste do Brasil. É importante aumentar a conscientização dos proprietários de equinos sobre o manejo alimentar adequado para minimizar a RGP.(AU)

Persistent infection in Neotoma fuscipes (Muridae: Sigmodontinae) with Ehrlichia phagocytophila sensu lato.

Dusky-footed wood rats (Neotoma fuscipes Baird) and two species of Peromyscus mice (P. maniculatus Wagner and P. truei Shufeldt) were collected over a 16-month period from three sites in Sonoma County, California. Blood was collected from 93 wood rats and 177 mice and serum or plasma was tested for seroreactivity with Ehrlichia phagocytophila sensu lato (also known as the human granulocytic ehrlichiosis agent). Thirty-five (37.6%) wood rats and 15 (8.5%) mice were seropositive. Positive Neotoma serology by site ranged from 9.4% to 62.1%. Polymerase chain reaction (PCR) testing for the Ehrlichia groESL heat shock operon was performed on all the seropositive and selected seronegative wood rats; 24 (68.6%) seropositive animals were PCR positive. Two seroconversions and no seroreversions were detected among 18 of the seropositive wood rats that were recaptured and tested multiple times (range = 2-6). Fourteen (77.8%) of the 18 were also PCR positive with six of these positive at every testing point (range = 2-6). One wood rat remained serologically and PCR positive in six specimens collected over a 14-month period. One male of 84 questing adult Ixodes pacificus Cooley & Kohls collected was PCR-positive for E. phagocytophila. Borrelia burgdorferi, the agent of Lyme disease, was cultured from ear punch biopsies from six of seven E. phagocytophila seropositive and one of four seronegative wood rats.

Mercury and methylmercury in fish and human hair from the Tapajós river basin, Brazil.

Mercury is being released in the Amazon in an abusive way due to goldmining activities. The Tapajós river basin was the first to be intensively exploited in the modern Amazon gold rush. Fish and hair samples as the best indicators of human methylmercury contamination were investigated in the main cities and villages along the Tapajós river basin. The upper basin has typical fish fauna with much larger carnivorous fish with higher mercury levels reaching an average value of 0.69 microgram.g-1 wet wt. in 43 fish. This was accompanied by high levels in hair of the human population living in the same area. The maximum hair value reach 151 micrograms.g-1 dry wt. with two villages presenting an average value close to 25 micrograms.g-1 dry wt. An analytical laboratory intercalibration exercise was performed between Japanese and Brazilian laboratories for total mercury analysis. Critical fish, areas, and more exposed human groups are identified.

An assessment of soil-to-plant concentration ratios for some natural analogues of the transuranic elements.

A field study was conducted in an area of enhanced, natural radioactivity to assess the soil to edible vegetable concentration ratios (CR = concentration in dry vegetable/concentration in dry soil) of 232Th, 230Th, 226Ra, 228Ra, and the light rare earth elements (REE's) La, Ce and Nd. Twenty-nine soil and 42 vegetable samples consisting of relatively equal numbers of seven varieties were obtained from 11 farms on the Pocos de Caldas Plateau in the state of Minas Gerais, Brazil. This region is the site of a major natural analogue study to assess the mobilization and retardation processes affecting Th and the REE's at the Morro do Ferro ore body and U series radionuclides at a nearby open pit U mine. Thorium (IV) serves as a chemical analogue for quadrivalent Pu and the light REE's (III) as chemical analogues for trivalent Am and Cm. The geometric mean CR's (all times 10(-4] decreased as 228Ra (148) greater than 226Ra (76) greater than La (5.4) greater than Nd (3.0) = Ce (2.6) greater than 232Th (0.6), or simply as M (II) greater than M (III) greater than M (IV). These differences may reflect the relative availability of these metals for plant uptake. Significant differences were found in the CR's (for any given analyte) among many of the vegetables sampled. The CR's for the different analytes were also highly correlated. The reasons for the correlations in CR's seen among elements with such diverse chemistries as Ra-REE or Ra-Th are not clear but are apparently related to the essential mineral requirements or mineral status of the different vegetables sampled. This conclusion is based on the significant correlations obtained between the Ca content of the dried vegetables and the CR's for all of the elements studied.

Current knowledge on oxidative stress in hepatic ischemia/reperfusion.

Ischemia/reperfusion (I/R) injury associated with hepatic resections and liver transplantation remains a serious complication in clinical practice, despite several attempts to solve the problem. The redox balance, which is pivotal for normal function and integrity of tissues, is dysregulated during I/R, leading to an accumulation of reactive oxygen species (ROS). Formation of ROS and oxidant stress are the disease mechanisms most commonly invoked in hepatic I/R injury. The present review examines published results regarding possible sources of ROS and their effects in the context of I/R injury. We also review the effect of oxidative stress on marginal livers, which are more vulnerable to I/R-induced oxidative stress. Strategies to improve the viability of marginal livers could reduce the risk of dysfunction after surgery and increase the number of organs suitable for transplantation. The review also considers the therapeutic strategies developed in recent years to reduce the oxidative stress induced by hepatic I/R, and we seek to explain why some of them have not been applied clinically. New antioxidant strategies that have yielded promising results for hepatic I/R injury are discussed.

The Current Knowledge of the Role of PPAR in Hepatic Ischemia-Reperfusion Injury.

Strategies to improve the viability of steatotic livers could reduce the risk of dysfunction after surgery and increase the number of organs suitable for transplantation. Peroxisome proliferator-activated receptors (PPARs) are major regulators of lipid metabolism and inflammation. In this paper, we review the PPAR signaling pathways and present some of their lesser-known functions in liver regeneration. Potential therapies based on PPAR regulation will be discussed. The data suggest that further investigations are required to elucidate whether PPAR could be a potential therapeutic target in liver surgery and to determine the most effective therapies that selectively regulate PPAR with minor side effects.

Evaluation of carcass and muscle traits in Santa Ines female lambs finished with different agricultural products / Avaliação de características da carcaça e do músculo de cordeiras Santa Inês terminadas com diferentes produtos agrícolas

The aim of this study was to evaluate the effect of different agricultural products on quantitative aspects of carcass, body constituents, cooking loss, shear force and colorimetry of the Longissimus lumborum and Triceps brachii muscles in Santa Ines lambs. 24 Santa Ines female lambs received one of four diets which were isoproteic and isoenergetic with fixed levels of forage (60%) and concentrate (40%) of corn and soybean meal during 45 days. The forages per diet differed: coast-cross hay (HAY), cassava hay (CASS), dehydrated by-product of pea crop (PEA) and sugarcane (SC). The average weight of the lambs at the beginning of the experiment was 26.35kg. Animals were slaughtered in a federally certified abattoir. Initial and final pH, cooking losses, color using the CIELAB system, shear force and the quantity of sarcomeres per 100µm were measured. Hot carcass, cold and half carcass weights were affected by treatments (P<0.05). The sarcomere length of Triceps brachii muscle 24 hours after slaughter differed between diets and coast-cross hay had the lowest value. The sarcomere length differed significantly between diets and the dehydrated by-product of pea crop had the lowest number of sarcomeres immediately after slaughter compared to other diets. There was no influence of diet on colorimetry, cooking loss and shear force. The decrease in pH followed the development of the process of rigor mortis in the Longissimus lumborum and Triceps brachii muscles in the first hour and up to 24 hours after slaughter. Diets did not alter the pH, water holding capacity, colorimetry or shear force. The pea by-product and sugarcane can replace traditional sources of fodder without depreciation of meat characteristics.(AU)

O objetivo deste estudo foi avaliar o efeito de diferentes produtos agrícolas sobre aspectos quantitativos da carcaça, constituintes do corpo, perda por cocção, força de cisalhamento e colorimetria dos músculos Longíssimus lumborum e Tríceps brachii em cordeiras Santa Inês. Vinte e quatro cordeiras Santa Inês receberam uma das quatro dietas, que foram isoproteicas e isoenergéticas, com níveis fixos de forragem (60%) e concentrado (40%) composto por milho e farelo de soja, durante 45 dias. As forragens diferiram entre as dietas: feno de coast cross (FENO), feno da parte aérea da mandioca (MAN), subproduto desidratado da cultura da ervilha (ERV) e cana-de-açúcar (CANA). O peso médio das cordeiras no início do experimento foi de 26,35kg. Os animais foram abatidos em frigorífico com inspeção sanitária federal. Foram avaliados o pH inicial e o final, as perdas por cocção, a cor, por meio do sistema CIELAB, a força de cisalhamento e a quantidade de sarcômeros em 100µm. Os pesos de carcaça quente, de carcaça fria e de meia-carcaça foram afetados pelos tratamentos (P<0,05). O comprimento do sarcômero do músculo Tríceps brachii 24 horas após o abate diferiu entre dietas e o feno coast cross apresentou o menor valor. O comprimento do sarcômero diferiu significativamente entre as dietas, e o subproduto da ervilha apresentou o menor número de sarcômeros imediatamente após o abate em comparação com as outras dietas. Não houve influência da dieta sobre as características de colorimetria, perda por cocção e força de cisalhamento. Houve diminuição do pH, seguido pelo desenvolvimento do processo de rigor mortis nos músculos Longíssimus lumborum e Tríceps brachii da primeira hora até 24 horas após o abate. As dietas não foram capazes de alterar o pH, a capacidade de retenção de água, a colorimetria ou a força de cisalhamento. O subproduto de ervilha e a cana-de-açúcar podem substituir as fontes tradicionais de forragem sem prejudicar as características da carne.(AU)

Ecological aspects of the free-living ticks (Acari: Ixodidae) on animal trails within Atlantic rainforest in south-eastern Brazil.

In a recent ecological study of the ticks on animal trails within an area of Atlantic rainforest in south-eastern Brazil, Amblyomma aureolatum, A. brasiliense, A. incisum, A. ovale and Haemaphysalis juxtakochi were found questing on the vegetation. Most of the ticks recorded by a small, man-made dam on the forest border were A. dubitatum but a few A. brasiliense and A. cajennense, one A. incisum and one H. juxtakochi were also found. The seasonal activity of the ticks indicated that A. incisum and A. brasiliense had one generation/year. On the animal trails, most tick species and stages quested on the vegetation at a height of 30-40 cm above ground level. The questing larvae and adults of A. incisum tended to be found higher, however, with the greatest numbers recorded 40-50 cm (larvae) or 60-70 cm (adults) above ground level. Most of the adult ticks (81.1%-100%), nymphs (78.6%-100%) and larval clusters (100%) found on a forest trail remained questing at the same location over a 24-h period. Carbon-dioxide traps in the rainforest attracted <50% of the ticks observed questing on the nearby vegetation and, curiously, the CO2 traps set deep in the forest attracted far fewer ticks than similar traps set by the dam. The ecological relationships between the ticks, their hosts and the rainforest environment are discussed.

Platelet rich plasma associated with heterologous fresh and thawed chondrocytes on osteochondral lesions of rabbits / Associação de plasma rico em plaquetas e condrócitos heterólogos frescos e descongelados em lesão osteocondral de coelhos

Chondrocytes obtained from stifle joint of New Zealand White rabbits were cultivated. Half of cells were maintained in culture for later implantation and the others frozen during six months to evaluate viability. A circular osteochondral defect was created in the right stifle of other twenty seven rabbits. The control group (CG) received no treatment. The thawed (TH) and fresh (FH) heterologous groups received, respectively, an implant of cultivated thawed or fresh heterologous chondrocytes associated with platelet rich plasma (PRP). The CG group showed greatest pain and lameness compared to the other groups seven days after the implantation. Microscopically, at 45 and 90 days, the TH and FH groups showed filling with cartilaginous tissue containing chondrocytes surrounded by a dense matrix of glycosaminoglycans. In the CG group, healing occurred with vascularized fibrous connective tissue without integration to the subchondral bone. Cryopreserved heterologous chondrocytes were viable for implantation and healing of osteochondral lesions; the association with PRP allows the fixation of cells in the lesion and offers growth factors which accelerates repair with tissue similar to articular hyaline cartilage.

Cultivaram-se condrócitos obtidos da articulação do joelho de coelhos. Metade das células foi mantida em cultura para posterior implantação, e a outra metade foi congelada durante seis meses com a finalidade de avaliar a viabilidade. Criou-se um defeito circular osteocondral no joelho direito de outros vinte e sete coelhos. O grupo controle (GC) não recebeu tratamento. Os grupos descongelado (TH) e fresco (FH) receberam, respectivamente, implantes heterólogos de condrócitos cultivados descongelados e frescos, associados com PRP. O grupo GC apresentou maior dor e claudicação em comparação com os outros grupos aos sete dias após o implante. Microscopicamente, aos 45 e 90 dias, os grupos TH e FH mostraram preenchimento da falha com tecido cartilaginoso contendo condrócitos circundados por uma matriz densa de glicosaminoglicanos. Nesse período, no grupo CG, a cura ocorreu com tecido conjuntivo fibroso vascularizado e sem integração com o osso subcondral. Condrócitos heterólogos criopreservados foram viáveis para implantação e tratamento de lesões osteocondrais; a associação com o PRP permitiu a fixação de células na lesão e ofereceu fatores de crescimento que aceleraram a reparação com o tecido semelhante à cartilagem hialina articular.

Efeitos do congelamento sobre condrócitos cultivados de coelhos / Effect of freezing on rabbit cultured chondrocytes

This work evaluated the effect of freezing on chondrocytes maintained in culture, aiming the establishment of a cell bank for future application as heterologous implant. Chondrocytes extracted from joint cartilage of nine healthy New Zealand White rabbits were cultivated and frozen with the cryoprotector 5 percent dimethylsulfoxide for six months. Phenotypic and scanning electron microscopy analyses were carried out to identify morphological and functional differences between fresh and thawed cells. After enzymatic digestion, a total of 4.8x10(5)cells per rabbit were obtained. Fresh chondrocytes showed a high mitotic rate and abundant matrix was present up to 60 days of culture. Loss of phenotypic stability was notable in the thawed chondrocytes, with a low labeling of proteoglycans and weak immunostaining of type II collagen. The present study showed important loss of chondrocyte viability under the freezing conditions. For future in vivo studies of heterologous implant, these results suggests that a high number of cells should be implanted in the host site in order to achieve an adequate number of viable cells. Furthermore, the chondrocytes should be implanted after two weeks of culture, when the highest viability rate is found.

Avaliaram-se os efeitos do congelamento sobre condrócitos mantidos em cultura, com o objetivo de se estabelecer um banco celular para futura aplicação como implante heterólogo. Condrócitos extraídos da cartilagem articular de nove coelhos saudáveis, da raça Nova Zelândia Branca, foram cultivados e submetidos ao congelamento, com o citoprotetor sulfóxido de dimetila a 5 por cento, por um período de seis meses. Análises fenotípicas e de microscopia eletrônica de varredura foram realizadas com o objetivo de identificar diferenças morfológicas e funcionais entre as células frescas e as descongeladas. Após a digestão enzimática, foram obtidas 4,8x10(5) células por coelho. Os condrócitos frescos apresentaram elevada taxa mitótica e abundante presença de matriz até os 60 dias de cultura. Nas culturas dos condrócitos descongelados, a perda de estabilidade fenotípica foi marcante, o que foi demonstrado pela baixa intensidade da coloração dos proteoglicanos e pela fraca imunomarcação do colágeno tipo II. Sob as condições de congelamento utilizadas, houve importante perda de viabilidade condrocítica. Para futuros estudos in vivo de implante heterólogo, estes resultados sugerem que o elevado número de células deve ser implantado no sítio hospedeiro, com o objetivo de se obter maior quantidade de células viáveis, e que os condrócitos deverão ser implantados com duas semanas de cultivo, período em que apresentam melhor taxa de viabilidade.