Immunoglobulin G profile in hyperacute rejection after multivisceral xenotransplantation.

INTRODUCTION: Xenotransplantation is a potential solution for the high mortality of patients on the waiting list for multivisceral transplantation; nevertheless, hyperacute rejection (HAR) hampers this practice and motivates innovative research. In this report, we describe a model of multivisceral xenotransplantation in which we observed immunoglobulin G (IgG) involvement in HAR. METHODS: We recovered en bloc multivisceral grafts (distal esophagus, stomach, small intestine, colon, liver, pancreas, and kidneys) from rabbits (n = 20) and implanted them in the swine (n = 15) or rabbits (n = 5, control). Three hours after graft reperfusion, we collected samples from all graft organs for histological study and to assess IgG fixation by immunofluorescence. Histopathologic findings were graded according to previously described methods. RESULTS: No histopathological features of rejection were seen in the rabbit allografts. In the swine-to-rabbit grafts, features of HAR were moderate in the liver and severe in esophagus, stomach, intestines, spleen, pancreas, and kidney. Xenograft vessels were the central target of HAR. The main lesions included edema, hemorrhage, thrombosis, myosites, fibrinoid degeneration, and necrosis. IgG deposition was intense on cell membranes, mainly in the vascular endothelium. CONCLUSIONS: Rabbit-to-swine multivisceral xenotransplants undergo moderate HAR in the liver and severe HAR in the other organs. Moderate HAR in the liver suggests a degree of resistance to the humoral immune response in this organ. Strong IgG fixation in cell membranes, including vascular endothelium, confirms HAR characterized by a primary humoral immune response. This model allows appraisal of HAR in multiple organs and investigation of the liver's relative resistance to this immune response.

Post-Adipose-Derived Stem Cells (ADSC) Stimulated by Collagen Type V (Col V) Mitigate the Progression of Osteoarthritic Rabbit Articular Cartilage.

Collagen is essential for cartilage adhesion and formation. In the present study, histology, immunofluorescence, morphometry, and qRT-PCR suggested that adipose-derived stem cells (ADSCs) stimulated by type V collagen (Col V) induce a significant increase of type II collagen (Col II) in the degenerative area of surgical-induced osteoarthritic rabbit articular cartilage (OA). In vitro, the effects of Col V on the proliferation and differentiation of ADSC were investigated. The expression of the cartilage-related genes Col2a1 and Acan was significantly upregulated and Pou5fl was downregulated post-ADSC/Col V treatment. Post-ADSC/Col V treatment, in vivo analyses revealed that rabbits showed typical signs of osteoarthritic articular cartilage regeneration by hematoxylin and eosin (H&E) and Safranin O/Fast Green staining. Immunohistochemical staining demonstrated that the volume of Col II fibers and the expression of Col II protein were significantly increased, and apoptosis Fas ligand positive significantly decreased post-ADSC/Col V treatment. In conclusion, the expression of Col II was higher in rabbits with surgical-induced osteoarthritic articular cartilage; hence, ADSC/Col V may be a promising therapeutic target for OA treatment.

Endoscopic features in a model of multivisceral xenotransplantation.

INTRODUCTION: Xenotransplantation and multivisceral transplantation are advanced therapeutic methods that still require a scientific basis. There are no experimental models of multivisceral transplantation available, particularly not the monitoring by endoscopy. Here, we describe the endoscopic features in a model of multivisceral xenotransplantation. METHODS: The distal esophagus, stomach, intestine, colon, liver, pancreas, and the kidneys with a common vascular pedicle were harvested from rabbits and implanted in swine (group I, n = 9) or in rabbits (group II, n = 4). Endoscopy was performed in the stomach, jejunum, and ascending colon at four consecutive time points (immediate after surgery and 10, 90, and 180 min after reperfusion). Lesions were macroscopically graded as mild, moderate, and severe. Biopsies were taken following sacrifice at 180 min after reperfusion. RESULTS: In group I, the stomach, jejunum, and colon manifested a progression of lesions with predominance of mild lesions after 10 min, mild to moderate lesions after 90 min, and moderate to severe lesions after 180 min. In animals from group II, endoscopy showed normal features at all time points after reperfusion. Histopathologic analysis confirmed the diagnosis of hyperacute rejection in group I. Grafts from group II animals presented normal or mild ischemic/reperfusion injury. CONCLUSION: All animals subjected to multivisceral xenotransplantation showed a progression of endoscopic lesions with time after transplantation, while animals subjected to allotransplantation showed no aberrations in endoscopy. We conclude that endoscopy is a useful tool in the assessment of hyperacute rejection of a xenograft.

Preliminary findings from a new animal model for Peyronie's disease involving extracorporeal shock waves.

OBJECTIVE: To develop an experimental model in rabbits to analyse the efficiency of extracorporeal shock wave therapy (ESWT) for Peyronie's disease. MATERIALS AND METHODS: We used 15 adult male rabbits divided into three equal groups. In group 1 (no penile ESWT) rabbits had three sessions of ESWT with 2000 shocks each (15 kV), but a rubber mat was placed between the shock head and rabbit to protect the penis; the rabbits were killed at 7 days after the last session of ESWT. In group 2 the rabbits had three sessions of ESWT using the same parameters, and were killed immediately after the last session to analyse the penis. In group 3 the rabbits had three sessions of ESWT as before but were killed at 7 days after the last session, and the penile tissue analysed macroscopically and histologically. RESULTS: The results showed clearly that the model was efficient, creating a similar situation to that when applying ESWT in the human penis. All of the rabbits in groups 2 and 3 had haematomas and diffuse petechiae after ESWT, and only four had urethral and penile bleeding. Almost all macroscopic changes disappeared after 48 h and only one rabbit in group 3 after 7 days had a haematoma on the dorsal penile surface. The histology (assessed using haematoxylin and eosin staining) of the cavernous body of the penis showed: unchanged histology in group 1; in group 2 there was a dilated and congested vascular space in the cavernous body, with interstitial extensive bleeding in the dermis; and in group 3 there was an increase in interstitial fibrous tissue in the cavernous septum, with deposition of collagen fibres and thickening of the tunica albuginea. CONCLUSION: The present model was efficient in producing tissue injury in the normal penis when treated with ESWT, suggesting that this promising model should be considered for use future studies of Peyronie's disease.

Experimental multivisceral xenotransplantation.

BACKGROUND: Organ shortage impairs the proposition of multivisceral transplantation to treat multiple organ failure. Interspecies (xeno) transplantation is a valid solution for organ shortage; however, suitable models of this advance are lacking. We describe an effective model of multivisceral xenotransplantation to study hyperacute rejection. METHODS: Under general anesthesia, we in block recovered the distal esophagus, stomach, small bowel, colon, liver, pancreas, spleen, and kidneys from donors and implanted heterotopically in the lower abdomen of recipients. Animals were divided into four groups: I-canine donor, swine recipient (n = 6); II - swine donor, canine recipient (n = 5); III-canine donor, canine recipient (n = 4); and IV-swine donor, swine recipient (n = 5). Groups I and II comprised experimental (xenotransplantation) and III and IV control groups (allotransplantation). During the experiment, we appraised recipient evolution and graft modification by sequential biopsy up to 3 h. At this time, we killed animals for autopsy (experimental end point). RESULTS: We accomplished all experiments successfully. Every grafts attained customary appearance and convenient urine output immediately after unclamp. Around 15 min after reperfusion, xenografts achieved signs of progressive hyperacute rejection and absence of urine output. At the end of experiments we observed moderate to severe hyperacute rejection at small bowel, colon, mesenteric lymph node, liver, spleen, pancreas, and kidney, while stomach and esophagus achieved mild lesions. In contrast, allograft achieved normal or minimum ischemia/reperfusion injury and constant urine output. CONCLUSION: The present procedure assembles a simple and effective model to study multivisceral xenotransplantation and may ultimately spread researches toward hyperacute rejection.

Age-related changes in urinary bladder intramural neurons.

A quantitative morphometric evaluation of the intramural plexus of the urinary bladder of adult and aged guinea-pigs was performed by histological analysis, scanning electron microscopy, and hystochemical methods, such as NADH-diaphorase and acetylcholinesterase (AChE). The round or oval shaped intramural neurons were revealed among the bundles of the smooth detrusor muscle in clusters containing a variable number of cells in the groups. In both adult control and aged animals, the ganglia were enveloped by a ganglionar capsule of connective tissue mainly composed of type I collagen fibers. The number of neurons NADH-diaphorase positives estimated in the intramural plexus was 1433+/-187.71 and 1107+/-120.67 in the adult control and aged groups, respectively. The perikaryon areas of the NADH-diaphorase neurons reactives ranged from 216.40 to 1809.30 microm(2) in adult control group and from 198.20 to 2096.25 microm(2) in aged group. The nuclear area showed an increase in aged animals. The number of AChE-positive neurons estimated in the intramural plexus was 3294.67+/-415 microm(2) in the adult control group and 1960.33+/-526 microm(2) in the aged group, showing a significant decrease in the latter group. This age-related morphological change in intramural neurons may contribute to changes in urinary bladder activities in the elderly.

XeCl excimer laser ablation of rabbit tibia bone: morphology of the irradiated site and self-limiting effect.

OBJECTIVE: The purpose of this work is to investigate the morphological changes of the rabbit tibia bone submitted to osteotomy with XeCl excimer laser. BACKGROUND DATA: Laser ablation of tissue is a relevant clinical application of high-power lasers. Due to the variety of laser wavelengths and properties of biological targets, the subject has not yet been completely explored. METHODS: In this study, four tibias were irradiated with six different durations. The applied energy density was 6.7 J/cm(2) per pulse at a 4-Hz repetition rate. RESULTS: The 24 samples had similar and well-defined craters that were free of carbonization. The ablation rates per pulse, at 60-120 seconds, were 3.8 and 1.9 microm at the compact bone and the marrow tissue, respectively. The ablation process ceased after 120 sec, with a 1.6-mm crater depth. CONCLUSIONS: In the present study, the laser used showed a self-limiting characteristic, which is a phenomenon that can be of great value in preserving important structures close to the working area, giving a margin of safety to the surgeon, in case of over-irradiation. This self-limiting effect is attributed to liquid filling the cavity by the bleeding and irrigation process.

Orthotopic small intestine transplantation in dogs with systemic graft drainage.

BACKGROUND: Small intestine transplantation has been accepted worldwide to treat complex cases of intestinal failure. Canine intestinal transplantation model is important in training the surgical technique and to study the complications of this procedure. Systemic graft venous drainage is frequently performed in clinic, although the consequences of this partial meso-caval shunt have not been studied in detail. AIM: To describe the surgical technique and clinical outcome of a canine intestinal transplantation model using mesenteric-caval graft drainage. METHOD: Adult mongrel dogs from University of São Paulo Animal Facility, São Paulo, SP, Brazil, were used as donors and recipients in ten consecutives orthotopic intestinal transplantation with mesenteric-caval venous drainage. Clinical examination and body weight measurement were performed daily in all animals. Necropsy was performed in animals presenting moribund state (lethargic posture, diarrhea and loss of over 35% of body weight) to determine cause of death and histological changes. RESULTS: Three recipients died before day 2 from technical complications and were excluded from the experiment. The remaining seven animals developed signs of graft rejection with onset on days 3-4 and died or were sacrificed presenting severe graft rejection between days 7-9. Necropsy and histology of the graft confirmed the diagnosis of severe acute cellular rejection. CONCLUSION: Small intestine transplantation with systemic drainage in dogs courses with analogous and lethal outcome between postoperative day 7 to 9 due to strong graft rejection. This model serves as an excellent pre-clinical model to study the main complications related to this transplantation.

A canine model of laparoscopic segmental liver resection.

Laparoscopic hepatectomy has been recently proposed for the treatment of liver tumors, however there is a lack of experimental models to study surgical technique and the metabolic reactions after this procedure. The dog is an important animal for research but the laparoscopic hepatectomy model is not well established in this animal. We describe the surgical laparoscopic technique of left liver segmentectomy in the dog and the preliminary results of this procedure. Female dogs weighting more then 15 kg were used. Four transversal abdominal incisions (two of 1 cm and two of 0.5 cm) were made for the introduction of the video camera and the other laparoscopic instruments. The liver was inspected and the left lobe was mobilized through incision of the left triangular hepatic ligament. The vascular pedicle corresponding to the left medial lobe (corresponding to segment II) was identified, dissected, and clamped, delimiting a correspondent ischemic area. The hepatic parenchyma was divided according to the previous delimitation with minimum bleeding. The segment of the liver was then removed through an enlarged abdominal incision. The incisions were closed by continuous suture. The mean time of the procedure was forty minutes. We observed normal clinical evolution without any sign of complications due to the hepatic resection, and normal augmentation of body weight on follow-up of more than 3 months. Left hepatectomy in the dog is a viable procedure and may serve for surgical training and development of research projects in this field.

Development of a urinary lithiasis localizer mechanism to couple ultrasound and extracorporeal lithotripsy equipment in canine model.

INTRODUCTION: Due to the evolution of extracorporeal lithotripsy equipment (ESWL) and presently, the fact that most part of the equipment does not present ultrasound to localize urinary calculi, a system that allows adapting ultrasound equipment to ESWL equipment was developed, disposing only of fluoroscopy. Thus, this equipment was developed and was tested in urinary stones in canine models, to check its precision in relation to fluoroscopy. METHOD: Seven male dogs were utilized with the introduction, in the bladder through the ureteral route, of chalkstones, with initial localization by fluoroscopy, with a further ultrasound coincidence check localization of the vesical stones, being submitted to ESWL with a 3-hour, 21 days and 60 days follow-up after the procedure. RESULTS: Success of localization in all animals was verified presenting elimination of stones in the first micturitions, after ESWL. No complications were verified in those animals for 60 days. CONCLUSION: We verified that this equipment can lead to an update of the equipment that use only fluoroscopy, increasing in this way, their technical capacity in the treatment of urinary calculi, mainly in cases of non-radiopaque stones.

Surface characteristics of implants influence their bone integration after simultaneous placement of implant and GBR membrane.

The purpose of this study was to evaluate the influence of titanium surface characteristics on bone integration of implants, and to describe the pattern of peri-implant tissue healing after simultaneous implant placement and guided bone regeneration. In four healthy mongrel dogs mandibular premolars were extracted. Two weeks following full mouth prophylaxis and 4 months after extractions, simultaneous membrane and implant surgeries were performed. Efforts were made to produce bony defects with dimensions of 7 x 7 x 7 mm. Into these, 24 standard ITI implants (diameter = 4.1 mm; length = 8 mm) with either a titanium plasma-sprayed (TPS) or a machined surface (MS) were placed. Although implants were inserted 4 mm into cancellous bone, difficulties in achieving optimal primary stability were encountered. All dogs were maintained on a soft diet. Chlorhexidine rinses were performed three times a week. Full mouth prophylaxis was performed every 2 weeks. In the case of membrane exposure, the membranes were removed prematurely (4-6 or 14-15 weeks after surgery). Two dogs were sacrificed at 16 weeks and two at 24 weeks after surgery. Nondecalcified histologic sections were processed and histometric analyses were carried out. When membranes were removed after 4-6 weeks, a vertical bone growth (VB) of 45-61% of the original defect was noted. After membrane removal at 14-15 weeks, similar VB was observed. However, if membranes were left in situ for 24 weeks, VB was between 79% and 96%. In this group of sites, the VB was 66% at 16 weeks and 86% at 24 weeks. Osseointegration in the regenerated bone area ranged from 12% to 32% for the TPS and from 0.0% to 3.6% for the MS implants at 16 and 24 weeks combined. Osseointegration in the pristine host bone area ranged from 16% to 35% for the TPS and from 0.0% to 11% for the MS sites at 16 and 24 weeks. In conclusion, the fraction of implant-bone integration was much higher in the pristine bone compared to that in the regenerated bone. TPS surfaces positively influenced the fraction of osseointegration in comparison to MS surfaces for both regenerated and pristine bone. Furthermore, early membrane removal negatively affected the fraction of bone defect fill.

Development of a urinary lithiasis localizer mechanism to couple ultrasound and extracorporeal lithotripsy equipment in canine model

INTRODUCTION: Due to the evolution of extracorporeal lithotripsy equipment (ESWL) and presently, the fact that most part of the equipment does not present ultrasound to localize urinary calculi, a system that allows adapting ultrasound equipment to ESWL equipment was developed, disposing only of fluoroscopy. Thus, this equipment was developed and was tested in urinary stones in canine models, to check its precision in relation to fluoroscopy. METHOD: Seven male dogs were utilized with the introduction, in the bladder through the ureteral route, of chalkstones, with initial localization by fluoroscopy, with a further ultrasound coincidence check localization of the vesical stones, being submitted to ESWL with a 3-hour, 21 days and 60 days follow-up after the procedure. RESULTS: Success of localization in all animals was verified presenting elimination of stones in the first micturitions, after ESWL. No complications were verified in those animals for 60 days. CONCLUSION: We verified that this equipment can lead to an update of the equipment that use only fluoroscopy, increasing in this way, their technical capacity in the treatment of urinary calculi, mainly in cases of non-radiopaque stones.

Orthotopic small intestine transplantation in dogs with systemic graft drainage

RACIONAL: O transplante de intestino delgado é atualmente indicado para tratar casos complexos de falência entérica. Transplante intestinal em cão é importante modelo experimental para treino da técnica cirúrgica e para estudar as complicações desse procedimento. Drenagem sistêmica do enxerto é freqüentemente realizada nos transplantes clínicos, embora sua conseqüência seja desconhecida. OBJETIVO: Descrever a técnica cirúrgica e a evolução clínica e histopatológica de modelo de transplante de intestino em cão. MÉTODO: Cães mestiços adultos foram usados como doadores e receptores em 10 transplantes ortotópico de intestino delgado com drenagem mesentérico-cava do enxerto. Exame clínico e verificação do peso corpóreo dos receptores foram realizados diariamente. Sacrifício sob anestesia e necropsia foi realizado quando os animais apresentavam estado clínico precário (postura letárgica, diarréia, e perda de peso maior do que 35%) ou óbito, para determinação do diagnóstico. RESULTADOS: Três recipientes morreram antes do segundo dia de pós-operatório por erro técnico e foram excluídos do experimento. Os setes receptores restantes apresentaram início de sinais clínicos de rejeição entre os dias 3-4 de pós-operatório e morreram ou foram sacrificados apresentando rejeição severa do enxerto entre os dias 7-9. Necropsia e histologia do enxerto confirmaram o diagnóstico de rejeição aguda grave. CONCLUSÃO: O transplante de intestino delgado com drenagem sistêmica em cão cursa com similar e letal evolução entre os dias de pós-operatórios 7-9 devido a forte rejeição do enxerto. Este modelo é excelente para o estudo pré-clínico das complicações do transplante de intestinal.

DNA measurements after radiation - induced tissue structure of thyroid gland of rats

INTRODUÇAO: A exposição da tireóide à irradiação está associada à alteração do componente cromossômico nessa glândula. OBJETIVO: Avaliar o conteúdo de DNA (ploidia) em glândula tireóide submetida à radiação. MATERIAL E MÉTODOS: Foram irradiadas tireóides de 75 ratos; 25 foram usados como grupo controle e não sofreram irradiação. A exposição à irradiação foi realizada com o uso de Cobalt-60 na região cervical anterior direita com espaço de 3-30cm, com anel traqueal de 2º e 6º e dose de 600 centigrays (cGY). O conteúdo de DNA (ploidia) foi obtido com o método de Feulgen-Thionin e quantificado com o aparelho CAS 200 de citometria estática. RESULTADO: Dos 92 casos, 88 (95,7 por cento) foram diplóides, independente do tempo de exposição; aneuploidia foi observada em quatro casos (4,3 por cento), somente no grupo sacrificado aos 33 dias. Oito casos foram excluídos por problemas técnicos. CONCLUSAO: A irradiação afeta muito precocemente o conteúdo de DNA nuclear levando a aneuploidia.

Radiographic aspects and angioarchitectural arrangements in corrosion casts of the blood supply to the human sternocleidomastoid muscle by the sternocleidomastoid branch of the occipital artery

A contribuicao do ramo esternocleidomastoideo da arteria occipital para a irrigacao do musculo esternocleidomastoideo foi avaliada em cadaveres humanos nao fixados, atraves da injecao de contraste radiografico e de resina polimerizavel para estudo da microvasculatura. O musculo foi dividido nos tercos superior, medio e inferior, a partir da sua insercao no processo mastoideo do osso temporal. Na maioria dos musculos, o pediculo superior apresentou-se formado por dois ramos paralelos longitudinais. Em todos os casos, o contraste radiografico atingiu ou ultrapassou a parte media do musculo. Na parte mais distal do terco inferior, ha pouca ou nenhuma contribuicao do pediculo superior para a irrigacao dessa regiao muscular sugerindo...

Avaliaçäo da integraçäo de retalho muscular na reconstruçäo esofágica após esofagectomia cervical parcial: estudo experimental em cäes / Evaluation of the integration muscle flap in esophageal reconstruction after partial cervical esophagectomy: experimental study in dogs

Objetivou-se desenvolver com metodologia experimental, um modelo cirúrgico preocupado com a complexidade da técnica, aplicabilidade e tempo de duraçäao, utilizando retalho do músculo esternocefálico para reconstruçäo parcial do esôfago cervical, estudando ainda a integraçäo do retalho através da cicatrizaçäo e circulaçäo. Utilizamos 30 cäes machos com peso médio de 14,37Kg. Após a observaçäo pós-operatória, os aniamis foram divididos aleatoriamente em dois grupos de quinze cäes para avaliaçäo da circulaçäo e cicatrizaçäo da reparaçäo esofágica. A grande maioria dos cäes (80 por cento) ganhou peso, näo apresentando dificuldade de deglutiçäo, episódios de regurgitaçäo, e endoscopicamente nenhum dos animais demonstrou presença de fístulas e estenoses. A injeçäo com neoprene látex permitiu verificar pequenos ramos arteriais provenientes do retalho muscular e que supriam a regiäo da reconstruçäo. Os achados histológicos demonstraram quadro de atividade inflamatória crônica, em fase remissiva, na maioria dos cäes analisados, caracterizando portanto integraçäo do retalho com o órgäo.

Vascularização arterial do músculo esternocleidomastóideo pelo pedículo superior: análise dos segmentos músculos-vasculares: estudo topográfico e estrutural no homem / Arterial supply of the human sternocleidomastoid muscle through the occipital artery branch: a segmentary musculo-vascular analysis

A irrigação do músculo esternocleidomastóideo atravésdo ramo da artéria occipital (pedículo superior) foi estudada em espécimes obtidos de 41 cadáveres formolizados e frescos, com auxílio de injeção de neoprene-látex, métodos radiológicos e corrosão. Foram também tomadas medidas antropométricas do tipo altura do indivíduo, comprimento do músculo esternocleidomastóideo e distâncias do processo mastóideo à incisura jugular, à incisura tireóidea superior, à cartilagem criocóidea e ao mento. O músculo esternocleidomastóideo foi dividido em seis porções iguais em sua linha longitudinal, denominadas respectivamente níveis 1, 2, 3, 4, 5 e 6, a partir da sua inserção. Verificou-se que em todos os espécimes estudados a irrigação atingiu o nível 3. Em 56,66(per cent) dos espécimes a irrigação atingiu ou superou o nível 4. Em nenhum espécime o nível 6 foi atingido. Isto permite inferir que a utilização do retalho do pedículo superior do músculo esternocleidomastóideo é segura quando utilizados 50(per cent) de seu comprimento. A partir desta extensão sua irrigação declina rapidamente e conseqüentemente sua utilização em reparações perde, portanto, sua margem de segurança. A porção extrema distal não apresentou irrigação pelo pedículo superior, fato este que deve ser levado em consideração no planejamento de reparações que necessitem de maior extensão do músculo. Foi encontrada correlação positiva entre o comprimento do músculo esternocleidomastóideo à distância mastóidea-mento e a altura. Não houve correlação entre o comprimento do músculo esternocleidomastóideo a extensáo irrigada. (au)