Histological analysis of elastic cartilages treated with alkaline solution / Análise histológica de cartilagens elásticas tratadas com solução alcalina

The elastic cartilage is composed by chondroblasts and chondrocytes, extracellular matrix and surrounded by perichondrium. It has a low regeneration capacity and is a challenge in surgical repair. One of obstacles in engineering a structurally sound and long-lasting tissue is selecting the most appropriate scaffold material. One of the techniques for obtaining biomaterials from animal tissues is the decellularization that decreases antigenicity. In this work, alkaline solution was used in bovine ear elastic cartilages to evaluate the decellularization and the architecture of the extracellular matrix. The cartilages were treated in alkaline solution (pH13) for 72 hours and lyophilized to be compared with untreated cartilages by histological analysis (hematoxylin-eosin, Masson's trichrome and Verhoeff slides). Areas of interest for cell counting and elastic fiber quantification were delineated, and the distribution of collagen and elastic fibers and the presence of non-fibrous proteins were observed. The results demonstrated that the alkaline solution caused 90% decellularization in the middle and 13% in the peripheral region, and maintenance of the histological characteristics of the collagen and elastic fibers and non-fibrous protein removal. It was concluded that the alkaline solution was efficient in the decellularization and removal of non-fibrous proteins from the elastic cartilages of the bovine ear.(AU)

A cartilagem elástica é composta por condroblastos e condrócitos, matriz extracelular e envolta por pericôndrio. Possui uma baixa capacidade de regeneração e é um desafio em reparos cirúrgicos. Um dos obstáculos na engenharia de tecido estruturalmente sólido e de longa duração é a seleção do material de arcabouço mais adequado. Uma das técnicas para obtenção de biomateriais oriundos de tecidos animais é a descelularização, que diminui a antigenicidade. Neste trabalho, foi utilizada solução alcalina em cartilagem elástica auricular bovina para avaliar a descelularização e a arquitetura da matriz extracelular. As cartilagens foram tratadas em solução alcalina (pH13) durante 72 horas e liofilizadas, e comparadas com cartilagens não tratadas por análise histológica (hematoxilina-eosina, tricrômio de Masson e Verhoeff). Foram determinadas as áreas de interesse para contagem celular e quantificação de fibras elásticas, observada a distribuição de colágeno e fibras elásticas e a presença de proteínas não fibrosas. Os resultados demonstraram que a solução alcalina causou 90% de descelularização na região central e 13% na região periférica, manutenção das características histológicas do colágeno e fibras elásticas e remoção das proteínas não fibrosas. Concluiu-se que a solução alcalina foi eficiente na descelularização e retirada de proteínas não fibrosas de cartilagens elásticas da orelha de bovinos.(AU)

Biochemical composition of the hoof capsule of buffaloes and its influence on hoof quality / Composição bioquímica do estojo córneo de bubalinos e sua influência na qualidade do casco

The purpose of this study was to establish the biochemical parameters of the abaxial wall, dorsal wall and sole of the hoof of the medial thoracic, lateral, and medial pelvic digits of buffalos. The hoof samples were subjected to destructive biochemical analyses to identify the dry material (DM), mineral matter (MM), organic matter (OM), crude protein (CP) and ether extract (EE) contents. Sulfur (S), calcium (Ca), potassium (K), phosphorus (P), zinc (Zn) and copper (Cu) levels were determined based on nondestructive biochemical analyses. The parameters of dry material, mineral matter, organic matter, crude protein and ether extract of hoof capsule of the digits of buffalos can be determined by means of both destructive and nondestructive biochemical analysis. In addition, this study revealed that the highest concentrations of DM, CP and minerals such as, K, Zn and Cu are concentrated in the digits that bear the greatest body mass weight, suggesting that there is a positive correlation between the aforementioned parameters and the strength and growth of the hoof capsule in the digits. As for the element S, this study demonstrated that its highest concentration is located in the lateral digits of the pelvic members.(AU)

O presente estudo objetivou estabelecer os parâmetros bioquímicos da muralha abaxial, muralha dorsal e sola do casco dos dígitos torácico medial e pélvico lateral dos bubalinos. Foram realizadas analises bioquímicas destrutivas das amostras dos cascos para se obterem os teores de matéria seca (MS), matéria mineral (MM), matéria orgânica (MO), proteína bruta (PB) e extrato etéreo (EE). As análises bioquímicas não destrutivas foram empregadas para se avaliarem os níveis de enxofre (S), cálcio (Ca), potássio (K), fósforo (P), zinco (Zn) e cobre (Cu). Concluiu-se que os parâmetros matéria seca, matéria mineral, matéria orgânica, proteína bruta e extrato etéreo do estojo córneo dos dígitos de bubalinos podem ser definidos por análises bioquímicas destrutivas e não destrutivas. Os maiores valores dos elementos minerais estão concentrados nos dígitos que suportam o maior peso do animal, sugerindo que existe uma relação positiva entre esses parâmetros. Além disso, este estudo revelou que as maiores concentrações de MS, PB e minerais como, K, Zn e Cu estão nos dígitos que carregam o maior peso de massa corporal, o que indica que há uma correlação positiva entre os parâmetros acima referidos, resistência e crescimento do estojo córneo dos dígitos. Em relação ao elemento de S, este estudo demonstrou que a sua maior concentração situa-se nos dígitos laterais dos membros pélvicos.(AU)

A double blind randomized study of oral clodronate in the treatment of bone metastases from tumors poorly responsive to chemotherapy.

Bisphosphonates are used in oncology as a means of decreasing complications due to bone metastases, in association with anticancer treatment, especially in patients with breast cancer, prostate cancer and myeloma. Little is known about the effects of bisphosphonates on bone metastases from other tumors and in particular from tumors for which no effective treatment is available. We conducted a randomized, double-blind placebo-controlled trial of oral clodronate in patients with bone metastases from tumors poorly responsive to chemotherapy, with the aims of evaluating the effects of this drug on symptoms control and bone metastases evolution. Sixty-six patients with poorly responsive tumors such as non-small cell lung cancer (NSCLC), bladder cancer, gastrointestinal cancers, kidney cancer, melanoma and metastatic carcinoma of unknown origin entered the study. Patients were randomized to receive either clodronate 1,600 mg/day for one year or identical placebo-containing tablets. Various parameters such as Karnofsky performance status, pain score (measured by a visual-analogue scale) and analgesic requirement were recorded at monthly intervals. Of the 66 patients enrolled, 9 were observed for one month or less; 7 were followed for two months; only 50 patients were followed for more than 2 months and could be adequately evaluated. At 3 months both clodronate and placebo-treated patients had a decrease in Karnofsky performance status, with the decrease being more evident in the placebo group. Mean pain scores showed an increase of pain in patients receiving placebo and a decrease of pain in patients receiving clodronate, although the difference failed to be statistically significant. Analgesics requirement increased in both groups, but significantly more in patients receiving placebo (p = 0.042), in whom increase in opioid requirements was particularly evident. Toxicity was low, with occasional gastroenteric discomfort in both groups. The main problem of this study was the difficulty in recruiting an adequate number of patients and following them for a sufficient period of time: general conditions rapidly deteriorated in many patients, and approximately 25% of the 66 enrolled were not considered evaluable; few patients survived for the length of the study, one year. This might partly account for the lack of significance of some of the parameters under study. With these limits, oral clodronate demonstrated some efficacy in symptom control and in reducing the need for analgesics.

A phase II randomised trial of 5-fluorouracil with or without interferon alpha-2a in advanced colorectal cancer.

With the association of 5-fluorouracil (5-FU) and alpha-interferon (IFN), objective responses as high as 26 63% have been reported in untreated patients with advanced colorectal cancer. However, grade 3-4 toxicity has also been reported. We have conducted a prospective phase II randomised study comparing 5-FU to 5-FU + IFN, to investigate whether the addition of IFN to a weekly 5-FU regimen devoid of significant toxicity used at our institutions could improve the effectiveness of 5-FU while maintaining acceptable toxicity. Patients with histologically proven advanced colorectal carcinoma were randomised to receive 5-FU 500 mg m-2 intravenous (i.v.) bolus on days 1-5 followed by 5-FU 500 mg m-2 i.v. bolus weekly from day 15, with or without IFN alpha-2a intramuscularly (i.m.) 1.5 mU daily on days 6-12 and 3 mU i.m. daily thereafter. The treatment was administered on an outpatient basis. Response was evaluated every 3 months, and treatment continued until progression or after two consecutive judgements of stable disease. Response rate was the main end point of the study. Of 141 patients eligible, 72 were randomised to 5-FU alone (arm A) and 69 to 5-FU + IFN (arm B). Responses were 9/72 (12.5%) in arm A and 6/69 (8.7%) in arm B; complete responses were three in arm A and two in arm B. Progression-free survival (median 4 months) and survival (median 12 months) were identical in the two arms. Toxicity was almost absent in arm A and moderate in arm B, represented mainly by haematological toxicity (usually leucopenia). In conclusion, overall survival was good in both arms of treatment and toxicity was moderate. While the response rate with 5-FU alone was in accord with the literature data, response to 5-FU + IFN was lower than expected. At least at this dosage and schedule, the association of 5-FU and IFN is no better than 5-FU alone and is of no clinical interest.