Imatinib Mesylate for the Treatment of Canine Mast Cell Tumors: Assessment of the Response and Adverse Events in Comparison with the Conventional Therapy with Vinblastine and Prednisone.

Mast cell tumors (MCTs) are common neoplasms in dogs, and treatments for these diseases include surgery, polychemotherapy and targeted therapy with tyrosine kinase inhibitors. This study aimed to evaluate the response and the adverse events of treatment with imatinib mesylate (IM) compared to conventional therapy using vinblastine and prednisolone (VP) in canine cutaneous MCTs. Twenty-four dogs were included in the study; 13 animals were treated with IM and 11 with VP. Tumor tissue samples were submitted for histological diagnosis, grading and KIT immunostaining. The response to treatment was assessed by tomographic measurements according to VCOG criteria. Adverse events were classified according to VCOG-CTCAE criteria. The IM and VP groups had dogs with similar breeds, gender, ages, MCT localization, WHO stages and lymph node metastasis profiles. Most MCTs were grade 2/low and had KIT- patterns 2 and 3. The objective response rate (ORR) was significantly higher (30.79%) in the IM group then in VP group (9.09%). Adverse events (AE) in IM group were all grade 1, significantly different from VP. In conclusion, IM presented better ORR and less severe adverse events when compared to VP, representing a suitable option for the treatment of low-grade canine MCTs.

Effects of oral probiotics administration on the expression of transforming growth factor ß and the proinflammatory cytokines interleukin 6, interleukin 17, and tumor necrosis factor α in skin wounds in rats.

BACKGROUND: Cytokines and growth factors play key roles during the tissue repair process. We aim to evaluate the effect of perioperative oral of probiotics, on the healing process in skin wound in rats, by histological aspects, and by the expression of TGF-ß, and the pro-inflammatory cytokines IL6, IL7, and TNF-α. METHODS: 72 adult male Wistar rats were split into two groups control (n = 36) and probiotic group (n = 36). Each group was subdivided into three subgroups with 12 animals each according to euthanasia day: 3rd, 7th, and 10th postoperative(PO) day. RESULTS: Wound contraction was faster with the use of probiotics (p = .013). Also fibrosis was significantly higher in the Probiotic group in the 7th PO day (p = .028). In the probiotic group, there was a reduction of TNF-α at 3th PO day (p = .023); and a reduction of IL6 in 7th PO day (p = .030). There was also a reduction of the expression of IL-17 in 3rd PO day (p = .039) and 7rd PO day (P = .024). In contrast, TGF-ß was lower in the 10th PO day (p = .031) in the probiotic group as compared to controls, indicating that the increase of the fibrosis caused negative feedback with the TGF-ß. CONCLUSION: Probiotics are associated with a shorter inflammatory phase by attenuating the expression of cytokines IL-6 and TNF-α and accelerating the reduction of IL-17 and TGF-ß, leading to faster and improved cutaneous healing in rats.

EFFECTS OF PROBIOTICS SUPPLEMENTATION ON SKIN WOUND HEALING IN DIABETIC RATS.

BACKGROUND: Example of wound contraction area at: A) day of surgery in the control group; B) 7PO in the control group; C) day of surgery in the probiotic group; D) 7PO in probiotic group. Chronic wounds in patients with Diabetes Mellitus often become incurable due to prolonged and excessive production of inflammatory cytokines. The use of probiotics modifies the intestinal microbiota and modulates inflammatory reactions. AIM: To evaluate the influence of perioperative supplementation with probiotics in the cutaneous healing process in diabetic rats. METHODS: Forty-six rats were divided into four groups (C3, P3, C10, P10) according to the treatment (P=probiotic or C=control, both orally administered) and day of euthanasia, 3rd or 10th postoperative days. All rats were induced to Diabetes Mellitus 72 h before starting the experiment with alloxan. Supplementation was initiated five days before the incision and maintained until euthanasia. Scalpel incision was guided by a 2x2 cm mold and the wounds were left to heal per second-intention. The wounds were digitally measured. Collagen densitometry was done with Picrosirius Red staining. Histological parameters were analyzed by staining by H&E. RESULTS: The contraction of the wound was faster in the P10 group which resulted in a smaller scar area (p=0.011). There was an increase in type I collagen deposition from the 3rd to the 10th postoperative day in the probiotic groups (p=0.016), which did not occur in the control group (p=0.487). The histological analysis showed a better degree of healing in the P10 group (p=0.005), with fewer polymorphonuclear (p<0.001) and more neovessels (p=0.001). CONCLUSIONS: Perioperative supplementation of probiotics stimulates skin wound healing in diabetic rats, possibly due to attenuation of the inflammatory response and increased neovascularization and type I collagen deposition.

Effects of probiotics supplementation on skin wound healing in diabetic rats / Suplementação perioperatória com probióticos na cicatrização de feridas cutâneas em ratos diabéticos

ABSTRACT Background: Chronic wounds in patients with Diabetes Mellitus often become incurable due to prolonged and excessive production of inflammatory cytokines. The use of probiotics modifies the intestinal microbiota and modulates inflammatory reactions. Aim: To evaluate the influence of perioperative supplementation with probiotics in the cutaneous healing process in diabetic rats. Methods: Forty-six rats were divided into four groups (C3, P3, C10, P10) according to the treatment (P=probiotic or C=control, both orally administered) and day of euthanasia, 3rd or 10th postoperative days. All rats were induced to Diabetes Mellitus 72 h before starting the experiment with alloxan. Supplementation was initiated five days before the incision and maintained until euthanasia. Scalpel incision was guided by a 2x2 cm mold and the wounds were left to heal per second-intention. The wounds were digitally measured. Collagen densitometry was done with Picrosirius Red staining. Histological parameters were analyzed by staining by H&E. Results: The contraction of the wound was faster in the P10 group which resulted in a smaller scar area (p=0.011). There was an increase in type I collagen deposition from the 3rd to the 10th postoperative day in the probiotic groups (p=0.016), which did not occur in the control group (p=0.487). The histological analysis showed a better degree of healing in the P10 group (p=0.005), with fewer polymorphonuclear (p<0.001) and more neovessels (p=0.001). Conclusions: Perioperative supplementation of probiotics stimulates skin wound healing in diabetic rats, possibly due to attenuation of the inflammatory response and increased neovascularization and type I collagen deposition.

RESUMO Racional: Feridas crônicas em pacientes diabéticos muitas vezes se tornam incuráveis devido à produção prolongada e excessiva de citocinas inflamatórias. A utilização de probióticos modifica a microbiota intestinal e modula reações inflamatórias. Objetivo: Avaliar a influência da suplementação perioperatória com probióticos no processo de cicatrização cutânea em ratos diabéticos. Método: Quarenta e seis ratos foram divididos em quatro grupos (C3, P3, C10, P10) conforme tratamento (P=probiótico ou C=controle, via oral) e dia de eutanásia: 3o ou 10o dia de pós-operatório. Todos os ratos foram induzidos ao diabete melito 72 h antes de iniciar o experimento com aloxana. A suplementação foi iniciada cinco dias antes da operação e mantida até a eutanásia. Foi realizada incisão com bisturi guiada por molde de 2x2 cm e a ferida foi deixada para cicatrizar por segunda intenção. As feridas foram medidas digitalmente. A densitometria de colágeno foi determinada com coloração picrosirius red. A histologia foi avaliada por coloração com H&E. Resultados: A contração da ferida foi maior no grupo P10, o que resultou em menor área cruenta (p=0,011). Houve aumento do colágeno tipo I do 3o para o 10o dia de pós-operatório no grupo P10 (p=0,016), o que não ocorreu no grupo controle (p=0,487). A análise histológica mostrou melhor grau de cicatrização no grupo P10 (p=0,005), com menos polimorfonucleares (p<0,001) e mais neovasos (p=0,001). Conclusões: A suplementação perioperatória de probióticos promove aceleração da cicatrização cutânea em ratos diabéticos, possivelmente por atenuar a resposta inflamatória e aumentar a neovascularização e a deposição de colágeno tipo I.

A prototype single-port device for pressurized intraperitoneal aerosol chemotherapy. Technical feasibility and local drug distribution

Abstract Purpose: To evaluate the technical feasibility and homogeneity of drug distribution of pressurized intraperitoneal aerosol chemotherapy (PIPAC) based on a novel process of intraperitoneal drug application (multidirectional aerosolization). Methods: This was an in vivo experimental study in pigs. A single-port device was manufactured at the smallest diameter possible for multidirectional aerosolization of the chemotherapeutic drug under positive intraperitoneal pressure. Four domestic pigs were used in the study, one control animal that received multidirectional microjets of 9 mL/sec for 30 min and three animals that received multidirectional aerosolization (pig 02: 9 mL/sec for 30 min; pigs 03 and 04: 3 mL/sec for 15 min). Aerosolized silver nitrate solution was applied for anatomopathological evaluation of intraperitoneal drug distribution. Results: Injection time was able to maintain the pneumoperitoneum pressure below 20 mmHg. The rate of moderate silver nitrate staining was 45.4% for pig 01, 36.3% for pig 02, 36.3% for pig 03, and 72.7% for pig 04. Conclusions: Intra-abdominal drug distribution had a broad pattern, especially in animals exposed to the drug for 30 min. Our sample of only four animals was not large enough to demonstrate an association between aerosolization and a higher silver nitrate concentration in the stained abdominal regions.

A prototype single-port device for pressurized intraperitoneal aerosol chemotherapy. Technical feasibility and local drug distribution.

PURPOSE: To evaluate the technical feasibility and homogeneity of drug distribution of pressurized intraperitoneal aerosol chemotherapy (PIPAC) based on a novel process of intraperitoneal drug application (multidirectional aerosolization). METHODS: This was an in vivo experimental study in pigs. A single-port device was manufactured at the smallest diameter possible for multidirectional aerosolization of the chemotherapeutic drug under positive intraperitoneal pressure. Four domestic pigs were used in the study, one control animal that received multidirectional microjets of 9 mL/sec for 30 min and three animals that received multidirectional aerosolization (pig 02: 9 mL/sec for 30 min; pigs 03 and 04: 3 mL/sec for 15 min). Aerosolized silver nitrate solution was applied for anatomopathological evaluation of intraperitoneal drug distribution. RESULTS: Injection time was able to maintain the pneumoperitoneum pressure below 20 mmHg. The rate of moderate silver nitrate staining was 45.4% for pig 01, 36.3% for pig 02, 36.3% for pig 03, and 72.7% for pig 04. CONCLUSIONS: Intra-abdominal drug distribution had a broad pattern, especially in animals exposed to the drug for 30 min. Our sample of only four animals was not large enough to demonstrate an association between aerosolization and a higher silver nitrate concentration in the stained abdominal regions.