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1.
J Vet Intern Med ; 38(3): 1651-1658, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38471970

RESUMO

BACKGROUND: Increased serum cortisol (COR) concentrations may induce glucocorticoid resistance by down-regulation of glucocorticoid receptor (GCR), resulting in decreased chemotherapy efficacy in dogs with lymphoma. HYPOTHESIS: Investigate the relationship between serum COR concentrations and chemotherapy outcomes in dogs with lymphoma. ANIMALS: Thirty client-owned dogs with lymphoma, with serum COR concentration measured using serum samples collected at diagnosis. METHODS: Retrospective study. Dogs were divided into 2 groups based on serum COR concentrations: a normal group (n = 16) with COR concentrations <6 µg/dL and a high group (14) with COR concentrations ≥6 µg/dL. We compared signalment, clinical signs, stage, type of lymphoma, adrenal gland size, alkaline phosphatase (ALP) activity, response to chemotherapy, progression-free survival (PFS), overall survival (OS), and rate of P-glycoprotein (P-gp)- and GCR-positive cells between the 2 groups. RESULTS: No significant differences were found in the demographic characteristics between the 2 groups. However, the high COR group exhibited a significantly lower response to chemotherapy, PFS, and OS compared with the normal COR group. Serum ALP activity was significantly higher in the high COR group than in the normal COR group. Adrenal gland size was also significantly larger in the high COR group. Although no significant differences were found in the rate of P-gp-positive cells between the 2 groups, the rate of GCR-positive cells was significantly lower in the high COR group. CONCLUSIONS AND CLINICAL IMPORTANCE: Our data suggests that measurement of serum COR concentrations may serve as a potential prognostic factor and evaluation index.


Assuntos
Doenças do Cão , Hidrocortisona , Linfoma , Animais , Cães , Doenças do Cão/tratamento farmacológico , Doenças do Cão/sangue , Estudos Retrospectivos , Linfoma/veterinária , Linfoma/tratamento farmacológico , Linfoma/sangue , Feminino , Masculino , Hidrocortisona/sangue , Resultado do Tratamento , Antineoplásicos/uso terapêutico
2.
Cancers (Basel) ; 15(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38067241

RESUMO

The transcription factor hypoxia-inducible factor 1α (HIF-1α) drives metabolic reprogramming in gliomas (GLs) under hypoxic conditions, promoting glycolysis for tumor development. Evofosfamide (EVO) releases a DNA-alkylating agent within hypoxic regions, indicating that it may serve as a hypoxia-targeted therapy. The aim of this study was to investigate the glycolytic metabolism and antitumor effects of EVO in a canine GL model. Our clinical data showed that overall survival was significantly decreased in GL dog patients with higher HIF-1α expression compared to that of those with lower HIF-1α expression, and there was a positive correlation between HIF-1α and pyruvate dehydrogenase kinase 1 (PDK1) expression, suggesting that glycolytic activity under hypoxia conditions may contribute to poor outcomes in canine GL. Our glycolysis assay tests showed that the glycolytic ATP level was higher than the mitochondrial ATP level in three types of canine GL cell lines by activating the HIF-1 signal pathway under hypoxia conditions, resulting in an overall increase in total cellular ATP production. However, treatment with EVO inhibited the glycolytic ATP level in the GL cell lines under hypoxia conditions by targeting HIF-1α-positive cells, leading to decrease in total cellular ATP production. Our in vivo tests showed that EVO significantly reduced tumor development compared to controls and temozolomide in murine GL models. A metabolic analysis demonstrated that EVO effectively suppressed glycolytic metabolism by eliminating HIF-1α-positive cells, suggesting that it may restore metabolism in canine GLs. The evidence presented here supports the favorable preclinical evaluation of EVO as a potential improvement in cancer metabolism.

3.
PLoS One ; 18(10): e0291727, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37792729

RESUMO

Immune checkpoint inhibitors (ICIs) have been developed for canine tumour treatment, and pilot clinical studies have demonstrated their antitumour efficacy in dogs with oral malignant melanoma (OMM). Although ICIs have been approved for various human malignancies, their clinical benefits in other tumour types remain to be elucidated in dogs. Here, we conducted a clinical study of c4G12, a canine chimeric anti-PD-L1 antibody, to assess its safety and efficacy in dogs with various advanced malignant tumours (n = 12) at the Veterinary Teaching Hospital of Hokkaido University from 2018 to 2023. Dogs with digit or foot pad malignant melanoma (n = 4), osteosarcoma (n = 2), hemangiosarcoma (n = 1), transitional cell carcinoma (n = 1), nasal adenocarcinoma (n = 1), B-cell lymphoma (n = 1), or undifferentiated sarcoma (n = 2) were treated with 2 or 5 mg/kg c4G12 every 2 weeks. Treatment-related adverse events of any grade were observed in eight dogs (66.7%), including elevated aspartate aminotransferase (grade 3) in one dog (8.3%) and thrombocytopenia (grade 4) in another dog (8.3%). Among dogs with target disease at baseline (n = 8), as defined by the response evaluation criteria for solid tumours in dogs (cRECIST), one dog with nasal adenocarcinoma and another with osteosarcoma experienced a partial response (PR), with an objective response rate of 25.0% (2 PR out of 8 dogs; 95% confidence interval: 3.2-65.1%). These results suggest that c4G12 is safe and tolerable and shows antitumor effects in dogs with malignant tumours other than OMM. Further clinical studies are warranted to identify the tumour types that are most likely to benefit from c4G12 treatment.


Assuntos
Adenocarcinoma , Melanoma , Neoplasias Bucais , Osteossarcoma , Humanos , Cães , Animais , Hospitais Veterinários , Hospitais de Ensino , Melanoma/tratamento farmacológico , Melanoma/veterinária , Melanoma/patologia , Resultado do Tratamento , Neoplasias Bucais/veterinária , Osteossarcoma/tratamento farmacológico , Osteossarcoma/veterinária , Melanoma Maligno Cutâneo
4.
Cancers (Basel) ; 15(11)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37296981

RESUMO

Although immune checkpoint inhibitors (ICIs), such as the anti-programmed death-ligand 1 (PD-L1) antibody, have been developed for the treatment of canine malignant melanoma, desirable clinical efficacies have not been achieved. Recent studies in humans have suggested that radiation therapy (RT) combined with ICIs induces robust systemic antitumour immunity in patients with cancer. This study retrospectively examined the therapeutic efficacy of combination therapy (hypofractionated RT and anti-PD-L1 antibody [c4G12]) in dogs with pulmonary metastatic oral malignant melanoma. The intrathoracic clinical benefit rate (CBR)/median overall survival (OS) in the no RT (n = 20, free from the effect of RT), previous RT (n = 9, received RT ≤8 weeks prior to the first c4G12 dose), and concurrent RT (n = 10, c4G12 therapy within ±1 week of the first RT fraction) groups were 10%/185 days, 55.6%/283.5 days (p < 0.05 vs. no RT group), and 20%/129 days (p > 0.05 vs. no RT group), respectively. The adverse events were considered to be tolerable in the combination therapy. Thus, hypofractionated RT before the initiation of c4G12 therapy can be an effective approach for enhancing the therapeutic efficacy of immunotherapy, with acceptable safety profiles. Further prospective clinical studies are required to confirm the findings of this study.

5.
Vet Comp Oncol ; 21(2): 279-290, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36802270

RESUMO

Expression of programmed death ligand 1 (PD-L1) on tumour cells provides an immune evasion mechanism by inducing suppression of cytotoxic T cells. Various regulatory mechanisms of PD-L1 expression have been described in human tumours, however, little is known in canine tumours. To investigate whether inflammatory signalling is involved in PD-L1 regulation in canine tumours, the effects of interferon (IFN)-γ and tumour necrosis factor (TNF)-α treatment were examined in canine malignant melanoma cell lines (CMeC and LMeC) and an osteosarcoma cell line (HMPOS). The protein level of PD-L1 expression was upregulated by IFN-γ and TNF-α stimulation. Upon IFN-γ stimulation, all cell lines showed an increase in expression of PD-L1, signal transducer and activator of transcription (STAT)1, STAT3 and genes regulated by STAT activation. Upregulated expression of these genes was suppressed by the addition of a JAK inhibitor, oclacitinib. Contrastingly, upon TNF-α stimulation, all cell lines exhibited higher gene expression of the nuclear factor kappa B (NF-κB) gene RELA and genes regulated by NF-κB activation, whereas expression of PD-L1 was upregulated in LMeC only. Upregulated expression of these genes was suppressed by the addition of an NF-κB inhibitor, BAY 11-7082. The expression level of cell surface PD-L1 induced by IFN-γ and TNF-α treatment was reduced by oclacitinib and BAY 11-7082, respectively, indicating that upregulation of PD-L1 expression by IFN-γ and TNF-α stimulation is regulated via the JAK-STAT and NF-κB signalling pathways, respectively. These results provide insights into the role of inflammatory signalling in PD-L1 regulation in canine tumours.


Assuntos
Doenças do Cão , Fator de Necrose Tumoral alfa , Humanos , Animais , Cães , Fator de Necrose Tumoral alfa/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , NF-kappa B/metabolismo , Interferon gama/farmacologia , Interferon gama/metabolismo , Doenças do Cão/tratamento farmacológico , Linhagem Celular Tumoral
6.
PLoS One ; 18(1): e0281143, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36701405

RESUMO

Spontaneous tumors are a major cause of death in cats. Treatment of human tumors has progressed dramatically in the past decade, partly due to the success of immunotherapies using immune checkpoint inhibitors, such as anti-programmed death 1 (PD-1) and anti-PD-ligand 1 (PD-L1) antibodies. However, little is known about the PD-1 pathway and its association with tumor disease in cats. This study investigated the applicability of anti-PD-1/PD-L1 therapy in feline tumors. We first determined the complete coding sequence of feline PD-L1 and PD-L2, and found that the deduced amino acid sequences of feline PD-L1/PD-L2 share high sequence identities (66-83%) with orthologs in other mammalian species. We prepared recombinant feline PD-1, PD-L1, and PD-L2 proteins and confirmed receptor-ligand binding between PD-1 and PD-L1/PD-L2 using flow cytometry. Next, we established an anti-feline PD-L1 monoclonal antibody (clone CL1Mab-7) to analyze the expression of PD-L1. Flow cytometry using CL1Mab-7 revealed the cell surface expression of PD-L1 in a feline macrophage (Fcwf-4) and five mammary adenocarcinoma cell lines (FKNp, FMCm, FYMp, FONp, and FONm), and showed that PD-L1 expression was upregulated by interferon-γ stimulation. Finally, immunohistochemistry using CL1Mab-7 also showed PD-L1 expression in feline squamous cell carcinoma (5/5, 100%), mammary adenocarcinoma (4/5, 80%), fibrosarcoma (5/5, 100%), and renal cell carcinoma (2/2, 100%) tissues. Our results strongly encourage further investigations of the PD-1/PD-L1 pathway as a potential therapeutic target for feline tumors.


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , Animais , Gatos , Humanos , Adenocarcinoma/patologia , Adenocarcinoma/veterinária , Anticorpos Monoclonais , Antígeno B7-H1/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/veterinária , Proteínas de Checkpoint Imunológico , Imuno-Histoquímica , Ligantes , Proteína 2 Ligante de Morte Celular Programada 1/genética , Doenças do Gato
7.
Sports Biomech ; : 1-17, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36342374

RESUMO

The present study characterised supporting leg kinetics (sweeping and pivot legs) during osoto-gari and investigated the relationship between kinetic variables and sweeping leg velocity at sweep contact. Fifteen black belt judoka performed osoto-gari. Motion data were recorded using a Mac3D motion analysis system (250 Hz), and ground reaction force (GRF) data were collected using four force plates (1,000 Hz). During the swing phase, the peak anterior (r = -0.535, p = 0.040) and upward (r = -0.693, p = 0.005) GRFs generated by the sweeping leg and the peak plantar flexion moment (r = 0.548, p = 0.034) and power (r = -0.700, p < 0.005) of the sweeping leg ankle joint significantly correlated with the sweeping leg velocity at sweep contact. During the throwing phase, the peak clockwise moment (r = -0.604, p = 0.017) correlated with the peak sweeping leg velocity. The peak knee extension moment (r = 0.602, p = 0.018), hip flexion moment (r = -0.589, p = 0.021) and knee power (r = -0.618, p = 0.016) of the pivot leg also correlated with the sweeping leg velocity at sweep contact. The results indicated that exertion of the sweeping leg ankle plantar flexors positively contributed to the sweeping velocity. Increasing whole-body rotation by contracting the pivot leg knee extensors is a crucial biomechanical factor in accelerating the sweeping leg at sweep contact.

8.
Sci Rep ; 12(1): 9265, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35665759

RESUMO

Immune checkpoint inhibitors (ICIs) such as anti-PD-L1 antibodies are widely used to treat human cancers, and growing evidence suggests that ICIs are promising treatments for canine malignancies. However, only some canine oral malignant melanoma (OMM) cases respond to ICIs. To explore biomarkers predictive of survival in dogs with pulmonary metastatic OMM receiving the anti-PD-L1 antibody c4G12 (n = 27), serum concentrations of prostaglandin E2 (PGE2), cytokines, chemokines, and growth factors were measured prior to treatment initiation. Among 12 factors tested, PGE2, interleukin (IL)-12p40, IL-8, monocyte chemotactic protein-1 (MCP-1), and stem cell factor (SCF) were higher in OMM dogs compared to healthy dogs (n = 8). Further, lower baseline serum PGE2, MCP-1, and vascular endothelial growth factor (VEGF)-A concentrations as well as higher IL-2, IL-12, and SCF concentrations predicted prolonged overall survival. These observations suggest that PGE2 confers resistance against anti-PD-L1 therapy through immunosuppression and thus is a candidate target for combination therapy. Indeed, PGE2 suppressed IL-2 and interferon (IFN)-γ production by stimulated canine peripheral blood mononuclear cells (PBMCs), while inhibition of PGE2 biosynthesis using the COX-2 inhibitor meloxicam in combination with c4G12 enhanced Th1 cytokine production by PBMCs. Thus, serum PGE2 may be predictive of c4G12 treatment response, and concomitant use of COX-2 inhibitors may enhance ICI antitumor efficacy.


Assuntos
Melanoma , Fator A de Crescimento do Endotélio Vascular , Animais , Antígeno B7-H1/metabolismo , Biomarcadores , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Dinoprostona/uso terapêutico , Cães , Interleucina-2/uso terapêutico , Leucócitos Mononucleares/metabolismo , Melanoma/tratamento farmacológico , Melanoma/veterinária , Neoplasias Cutâneas , Melanoma Maligno Cutâneo
9.
Vet Comp Oncol ; 20(1): 324-335, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34719098

RESUMO

Cancer stem-like cells (CSCs) cause treatment failure in various tumours; however, establishing CSC-targeted therapies has been hampered by difficulties in the identification and isolation of this small sub-population of cells. Recent studies have revealed that tumour cells with low proteasome activity display a CSC phenotype that can be utilized to image CSCs in canines. This study visualizes and reveals the CSC-like properties of tumour cells with low proteasome activity in HMPOS (osteosarcoma) and MegTCC (transitional cell carcinoma), which are canine cell lines. The parent cells were genetically engineered to express ZsGreen1, a fluorescent protein connected to the carboxyl-terminal degron of canine ornithine decarboxylase that accumulates with low proteasome activity (ZsG+ cells). ZsG+ cells were imaged and the mode of action of this system was confirmed using a proteasome inhibitor (MG-132), which increased the ZsGreen1 fluorescence intensity. The CSC-like properties of ZsG+ cells were evaluated on the basis of cell divisions, cell cycle, the expression of CSC markers and tumourigenicity. ZsG+ cells underwent asymmetric divisions and had a low percentage of G0/G1 phase cells; moreover, ZsG+ cells expressed CSC markers such as CD133 and showed a large tumourigenic capability. In histopathological analysis, ZsG+ cells were widely distributed in the tumour samples derived from ZsG+ cells and in the proliferative regions of the tumours. The results of this study indicate that visualized canine tumour cells with low proteasome activity have a CSC-like phenotype and that this visualization system can be utilized to identify and isolate canine CSCs.


Assuntos
Neoplasias Ósseas , Doenças do Cão , Osteossarcoma , Animais , Neoplasias Ósseas/patologia , Neoplasias Ósseas/veterinária , Linhagem Celular Tumoral , Doenças do Cão/patologia , Cães , Células-Tronco Neoplásicas/patologia , Osteossarcoma/patologia , Osteossarcoma/veterinária , Complexo de Endopeptidases do Proteassoma/metabolismo
10.
Sports Biomech ; : 1-13, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34662255

RESUMO

The purpose of this study was to determine biomechanical factors for the effective execution of the osoto-gari technique by comparing differences between black belt and white belt judokas. Twenty-two male judokas (12 black belts; 10 white belts) performed osoto-gari, and the motion data were recorded using a Mac3D motion analysis system (250 Hz). The peak angular momentums of the trunk and leg of the uke were larger in the black belts than in the white belts, suggesting that the black belts rotated the uke's body more effectively than the white belts. During the swing phase, the peak angular velocities of the arms and trunk twist in the black belts were larger compared to the white belts. During the throwing phase, the black belts had substantially greater peak angular velocities of the arms, upper torso, and trunk twist. Additionally, the timing of the peak value of the upper torso and trunk twist of the black belts was closer to sweeping leg contact than that of the white belts. The results can provide coaches with suggestions for improving training protocol design when teaching osoto-gari and for helping novices more efficiently master the technique.

11.
Mol Ther Oncolytics ; 22: 143-151, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34514095

RESUMO

Metformin has many anti-cancer effects, alone or in combination with radiation. However, the mechanism underlying its radio-sensitized effect is still unclear, especially for cancer stem-like cells (CSCs). Here, the radio-sensitized effect of metformin was investigated, and its mechanism was revealed in CSCs derived from canine osteosarcoma cell line (HMPOS), a canine osteosarcoma cell line. Spheroid cells (SCs) were used as CSCs-rich cells derived from sphere formation, and SCs were compared with normal adherent culture cells (ACs). The radio-sensitizing effect of metformin using clonogenic assay and tumor growth in mice xenograft model were evaluated, and the mechanism of its radio-sensitization focusing on mitochondrial function was revealed. Metformin significantly enhanced radio-sensitivity of SCs through its inhibition of the mitochondrial function, as shown by decreased oxygen consumption, decreased mitochondrial membrane potential, and decreased ATP production. Additionally, SCs had a higher ability of mitochondrial respiration than ACs, which may have caused difference of their sensitivity of metformin and irradiation. In conclusion, mitochondrial function might play an important role in the sensitivity of metformin and irradiation, and drugs that target mitochondrial respiration, such as metformin, are promising radio-sensitizers to target CSCs.

12.
Vet Med Sci ; 7(4): 1120-1130, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33713574

RESUMO

Allogeneic hematopoietic cell transplantation (HCT) has been an effective treatment for human patients with haematological malignancies (Baron & Storb, 2006; Bair et al., 2020; Copelan et al., 2019). However, the optimal pretransplant conditioning treatment is unclear in canine allogeneic HCT. This pilot study aimed to evaluate the safety and efficacy of total lymphoid irradiation (TLI) with volumetric modulated arc therapy (VMAT) for a nonmyeloablative HCT conditioning. Six healthy dogs were treated with 8 or 12 Gy TLI using VMAT. Haematological and physical changes were recorded over 8 weeks. To assess the effect of peripheral lymphocyte condition, lymphocyte subset and proliferative ability were examined. At the end of the experiment, necropsy was performed. All dogs showed mild-to-moderate neutropenia and thrombocytopenia, and these haematological changes resolved spontaneously. One dog treated with 8 Gy TLI developed transient cutaneous infection. No major complication was seen in the other seven dogs. Myelocytes and erythroblast cytopenia of bone marrow were detected in two dogs treated with 12 Gy TLI. This study is the first report of TLI using VMAT in dogs, and results suggest that this regimen is a feasible nonmyeloablative treatment.


Assuntos
Cães/cirurgia , Transplante de Células-Tronco Hematopoéticas/veterinária , Irradiação Linfática/veterinária , Radioterapia de Intensidade Modulada/veterinária , Condicionamento Pré-Transplante/veterinária , Animais , Transplante de Células-Tronco Hematopoéticas/métodos , Masculino , Projetos Piloto , Condicionamento Pré-Transplante/efeitos adversos , Condicionamento Pré-Transplante/métodos
13.
NPJ Precis Oncol ; 5(1): 10, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33580183

RESUMO

Immunotherapy targeting programmed cell death 1 (PD-1) and PD-ligand 1 (PD-L1) represents promising treatments for human cancers. Our previous studies demonstrated PD-L1 overexpression in some canine cancers, and suggested the therapeutic potential of a canine chimeric anti-PD-L1 monoclonal antibody (c4G12). However, such evidence is scarce, limiting the clinical application in dogs. In the present report, canine PD-L1 expression was assessed in various cancer types, using a new anti-PD-L1 mAb, 6C11-3A11, and the safety and efficacy of c4G12 were explored in 29 dogs with pulmonary metastatic oral malignant melanoma (OMM). PD-L1 expression was detected in most canine malignant cancers including OMM, and survival was significantly longer in the c4G12 treatment group (median 143 days) when compared to a historical control group (n = 15, median 54 days). In dogs with measurable disease (n = 13), one dog (7.7%) experienced a complete response. Treatment-related adverse events of any grade were observed in 15 dogs (51.7%). Here we show that PD-L1 is a promising target for cancer immunotherapy in dogs, and dogs could be a useful large animal model for human cancer research.

14.
J Phys Ther Sci ; 31(9): 717-723, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31631944

RESUMO

[Purpose] We investigated the effects of a specifically designed exercise program that focused on the arches of the foot and the forefoot (the "Building Osteo Neatly Exercise" program) in college-aged females. [Participants and Methods] Forty college-aged females were divided randomly into experimental and control groups. The experimental group underwent the Building Osteo Neatly Exercise program for 60 min once a week for 4 months. In both groups, the plantar pressure distribution and quantitative ultrasound parameters of the calcaneus (speed of sound and bone area ratio) were evaluated at the beginning and end of the study. The plantar pressure distribution during walking was measured using a pressure plate to evaluate the deviation from the ideal values for the following: contact time, contact duration, peak pressure time, and foot pressure, all measured in the rear foot (the external and internal sides), medial forefoot including (the hallux and second and third toes), and lateral forefoot (the fourth and fifth toes). [Results] After completing the program, the speed of sound and bone area ratio had increased significantly in the experimental group and were significantly higher than those in the control group. The experimental group showed significant improvements in the deviations from the ideal values in contact time and contact duration in the medial forefoot, all four parameters in the lateral forefoot, and pressure in the rear foot. [Conclusion] College-aged females who participated in the Building Osteo Neatly Exercise program once weekly for 4 months exhibited significant improvements in bone strength in the calcaneus and in foot function, as shown by the plantar pressure distribution. Further studies are needed to examine the outcomes of the Building Osteo Neatly Exercise program in an elderly population.

15.
Vet Comp Oncol ; 17(2): 119-129, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30549190

RESUMO

Cancer stem-like cells (CSCs) are self-renewing cells comprising a small subpopulation in tumours, and generate differentiated progeny through asymmetric division. It has been shown that CSCs are resistant to ionizing radiation, and this feature could be one of the mechanisms of tumour recurrence after radiation therapy. Much attention has been focused on to target CSCs; however, difficult of isolating CSCs and lack of knowledge on their radiosensitivity have limited this kind of research in veterinary medicine. In the present study, sphere-forming cells (SC), cultured using sphere formation method, were isolated from four type of canine tumour cell lines and evaluated if they have CSCs-like properties by expression of CSCs markers (real-time polymerase chain reaction) and capacity of tumorigenesis (xenograft transplantation in nude mice), and were assessed radiosensitivity (clonogenic survival assay) and DNA repair kinetics (immunofluorescence staining for p53-binding protein 1) after X-ray irradiation in comparison with the corresponding normal adherent culture cells (AC). All SCs were isolated using sphere formation and showed high gene expression of CD133 and tumorigenic ability as compared with AC. All SCs were significantly resistant against X-ray irradiation as compared with AC. In addition, the amount of DNA double-strand breaks after X-ray irradiation were significantly lower in SC compared with the corresponding AC. These results indicate that SC isolated through sphere formation possess CSCs-like characteristics and CSCs are important factor that affect radiosensitivity in canine tumours. In addition, radioresistance of CSCs may depend on reaction of DNA double-strand break after X-ray exposure.


Assuntos
Células-Tronco Neoplásicas/efeitos da radiação , Esferoides Celulares/efeitos da radiação , Animais , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Doenças do Cão/radioterapia , Cães , Feminino , Marcadores Genéticos , Camundongos , Camundongos Nus , Tolerância a Radiação , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Células-Tronco , Sobrevida
16.
Open Vet J ; 8(4): 441-444, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538936

RESUMO

A 10-year-old castrated male cross-breed dog was referred for the repair of perineal hernia with bladder retroflexion and a mass lesion in the hernial sac. Surgical treatment was performed and the mass was identified as degenerated adipose tissue that was suspected to be derived from the omentum. The hernial contents were reduced without difficulty, and the dog exhibited a normal recovery. Two days after surgery, the dog suddenly exhibited anorexia and azotemia. Exploratory laparotomy was performed, which showed the dilation of both ureters with discoloration of the bladder serosa and strangulation of the urinary bladder neck. Careful inspection confirmed that a fibrous band, which was connected to the mass-like degenerated adipose tissue, had caused the strangulation. Two days after removal of these tissues, the dog recovered, with normal findings on blood biochemical analysis. The condition described in this report is an uncommon complication of perineal hernia repair. The findings suggest that degenerative fat tissue should be resected during perineal hernia repair in dogs, in order to prevent possible bladder strangulation after surgery.

17.
J Vet Med Sci ; 80(9): 1456-1458, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30012929

RESUMO

A 10-year-old cat presented for evaluation with a 1-month history of salivation and oral bleeding. A right mandibular mass was palpated and computed tomography examination revealed entire bone proliferation. Mandibular bone biopsy was performed, and histopathological diagnosis was vascular hamartoma. The cat suddenly died on day 140.


Assuntos
Doenças do Gato/diagnóstico , Hamartoma/veterinária , Mandíbula/patologia , Tomografia Computadorizada por Raios X/veterinária , Animais , Gatos , Evolução Fatal , Hamartoma/diagnóstico , Tomografia Computadorizada por Raios X/métodos
18.
Sci Rep ; 7(1): 8951, 2017 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-28827658

RESUMO

Immunotherapy targeting immune checkpoint molecules, programmed cell death 1 (PD-1) and PD-ligand 1 (PD-L1), using therapeutic antibodies has been widely used for some human malignancies in the last 5 years. A costimulatory receptor, PD-1, is expressed on T cells and suppresses effector functions when it binds to its ligand, PD-L1. Aberrant PD-L1 expression is reported in various human cancers and is considered an immune escape mechanism. Antibodies blocking the PD-1/PD-L1 axis induce antitumour responses in patients with malignant melanoma and other cancers. In dogs, no such clinical studies have been performed to date because of the lack of therapeutic antibodies that can be used in dogs. In this study, the immunomodulatory effects of c4G12, a canine-chimerised anti-PD-L1 monoclonal antibody, were evaluated in vitro, demonstrating significantly enhanced cytokine production and proliferation of dog peripheral blood mononuclear cells. A pilot clinical study was performed on seven dogs with oral malignant melanoma (OMM) and two with undifferentiated sarcoma. Objective antitumour responses were observed in one dog with OMM (14.3%, 1/7) and one with undifferentiated sarcoma (50.0%, 1/2) when c4G12 was given at 2 or 5 mg/kg, every 2 weeks. c4G12 could be a safe and effective treatment option for canine cancers.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antígeno B7-H1/antagonistas & inibidores , Doenças do Cão/tratamento farmacológico , Melanoma/veterinária , Neoplasias Bucais/veterinária , Sarcoma/veterinária , Animais , Anticorpos Monoclonais/farmacologia , Proliferação de Células , Células Cultivadas , Doenças do Cão/imunologia , Cães , Relação Dose-Resposta a Droga , Feminino , Imunoterapia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Masculino , Melanoma/tratamento farmacológico , Melanoma/imunologia , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/imunologia , Projetos Piloto , Sarcoma/tratamento farmacológico , Sarcoma/imunologia , Resultado do Tratamento
19.
Exp Eye Res ; 86(3): 512-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18262523

RESUMO

Oxygen saturation (OS) levels in the juxta-papillary retina particularly inferotemporal retina were investigated in open-angle glaucoma (OAG) patients as well as normal subjects. Fifty-six eyes of 56 OAG Japanese patients and 20 eyes of 20 age-matched normal subjects were recruited for the study. OAG eyes (56) were subdivided into two groups: 15 eyes of low-tension (LT) subgroup and 41 eyes of high-tension (HT) subgroup. The average of age of the LT, HT subgroup and normal group were 60.5, 55.9 and 52.6 years, respectively. OS levels in the retina were measured using a Fourier transform-based spectral retinal imaging (SRI) system (Retinal Cube; ASI Co. Migdal Hemak, Israel), with which OS levels in the fundus could be computed at every pixel point of a 35 degrees fundus image. We calculated OS levels at five points in the retina near the optic disc and retinal arteries and veins in all eyes. The OS levels were also compared with the results analyzed using Humphrey visual field Analyzer with the program 30-2 SITA. At the superior and nasal juxta-papillary retinal points, OS level of the LT subgroup showed significant decrease as compared with the HT subgroup and the normal group (p=0.048-0.009). The LT and the HT subgroups were significantly lower than the normal group at the inferotemporal and the average of the retinal points (p=0.047-0.001). There were no statistically significant differences among the three groups in regards to the OS in the retinal artery. There was a statistical significant correlation between the mean of total deviation of the 17 points in the upper arcuate area and OS of the inferotemporal point (p=0.018), and between mean deviation and the average of OS of the inferotemporal and the superotemporal point (p=0.037) in the HT subgroup. However, there was no significant correlation in the LT subgroup. OS levels in the retina were especially decreased in the low-tension glaucoma subtype. There was a correlation between the visual field defect and OS in the HT eyes in the inferotemporal region. OS measurement may be a novel adjunct to study glaucoma patients.


Assuntos
Glaucoma de Ângulo Aberto/metabolismo , Oxigênio/sangue , Retina/química , Adulto , Idoso , Técnicas de Diagnóstico Oftalmológico , Análise de Fourier , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular , Pessoa de Meia-Idade , Vasos Retinianos/química , Campos Visuais
20.
Retina ; 24(1): 57-62, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15076945

RESUMO

PURPOSE: To compare optical coherence tomography (OCT) images of idiopathic epiretinal membranes (ERMs) with those of secondary ERMs. METHODS: OCT was performed on 70 eyes of 63 consecutive patients with biomicroscopic evidence of ERMs and 23 eyes of 23 healthy volunteers without ERMs. OCT findings were correlated with the clinical pathogenesis of the ERM. RESULTS: Evaluation by OCT established that 48 of 70 ERMs were globally adherent to the retina and that 22 of 70 ERMs were focally adherent to the retina. When correlated to clinical pathogenesis, 20% of idiopathic membranes and 52% of secondary membranes were focally attached to the retina. There was a significant difference in the pattern of membrane attachment to the retina in the two pathogenic groups (P = 0.007). Eight of nine eyes with macular pseudoholes were associated with globally adherent membranes. CONCLUSION: Secondary ERMs are more likely to be characterized by focal retinal adhesion than are primary ERMs. Primary ERMs tend to be globally adherent. This finding may contribute to understanding the underlying mechanisms of ERM formation in different clinical settings.


Assuntos
Membrana Epirretiniana/diagnóstico , Macula Lutea/patologia , Tomografia de Coerência Óptica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Retinopatia Diabética/complicações , Membrana Epirretiniana/etiologia , Feminino , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Descolamento Retiniano/complicações , Oclusão da Veia Retiniana/complicações , Aderências Teciduais
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