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1.
Vet Sci ; 10(9)2023 Aug 22.
Article in English | MEDLINE | ID: mdl-37756055

ABSTRACT

Of intracranial tumors, primary central nervous system lymphoma (PCNSL) is rare in dogs. Herein, we describe our experience with two dogs (a 3-year-old intact female toy poodle and a 5-year-old spayed female toy poodle) that developed neurological symptoms. Magnetic resonance imaging (MRI) revealed intracranial disseminated lesions. Cerebrospinal fluid (CSF) examination revealed pleocytosis and B-cell monoclonal proliferation in both cases. PCNSL or secondary central nervous system lymphoma (SCNSL) was diagnosed on the basis of MRI findings and CSF examinations. Nimustine (ACNU) is a nitrosourea alkylating agent, a class of drugs that includes lomustine. Nimustine is mainly used to treat human intracranial neoplasia because of its high permeability across the blood-brain barrier. The dogs in this study were treated with combined chemotherapy comprising nimustine and prednisolone, which achieved complete or nearly complete remission of neurological symptoms and long-term survival (>2583 days and 1218 days), but with problematic adverse effects. We determined that the dose of nimustine for canine PCNSL or SCNSL with intravenous infusion was 25-30 mg/m2 every 3-4 weeks for a total of four times; however, the data were insufficient to determine the optimal regimen.

2.
Vet Sci ; 9(12)2022 Nov 25.
Article in English | MEDLINE | ID: mdl-36548821

ABSTRACT

Prevention of hypothermia induced by anesthesia and enhanced by low environmental temperatures is difficult in magnetic resonance imaging (MRI) examinations in dogs as forced warming devices, including magnetic materials, are not acceptable for use in the MRI room. A hot water bottle (HWB) can be carried into an MRI examination room and can contribute to the prevention or attenuation of hypothermia. Here, we retrospectively investigated the effects of HWB on body temperature during MRI examinations in dogs under general anesthesia (GA). From anesthesia records of the Veterinary Medical Teaching Hospital, Okayama University of Science, validated data of 100 dogs that underwent an MRI examination under GA were obtained and divided into the following two groups: one group received HWB, while the other did not. Decrease in rectal temperature 15 min after intubation was significantly smaller in the group using HWB than in the group without HWB. In conclusion, the use of hot water bottles might be one of the methods to attenuate hypothermia in the early period but should not be expected for complete prevention of hypothermia, and it was not recommendable necessarily for body temperature management during MRI examinations in dogs under general anesthesia.

3.
J Vet Med Sci ; 84(10): 1430-1436, 2022 Oct 07.
Article in English | MEDLINE | ID: mdl-36058877

ABSTRACT

Cryptorchidism is defined as the failure of the testis to descend into the scrotal position. Bulls with cryptorchidism have problems in both meat quality and husbandry management; thus, it is greatly important to accurately identify the retained testis and remove it during the early stage. Abdominal computed tomography (CT) was performed under general anesthesia in 34 bulls aged 3-9 months with cryptorchidism. All bulls underwent laparoscopic or incision approach for cryptorchidectomy, and 40 testes were dissected. The detection rates of retained testes were 64.5% in the abdominal cavity and 100% in the subcutaneous inguinal region, and the total detection rate was 72.5%. Furthermore, all cases in this study were suspected to have intra-abdominal cryptorchidism in primary care, but CT revealed that 22.5% of cases had cryptorchidism in the subcutaneous inguinal region. The CT value (mean ± standard deviation) of the retained testes was 20.96 ± 7.54 Hounsfield Unit, and the CT value and size of the retained testes showed a positive weak correlation with bovine age. Therefore, there is the demerit that general anesthesia and a huge device are necessary; nevertheless, CT is suggested to be useful in identifying the location of retained testes and selecting an appropriate surgical approach in bulls with cryptorchidism. Moreover, CT findings suggested that the maturation of the retained testes might depend not on the descending process but on age.


Subject(s)
Cattle Diseases , Cryptorchidism , Laparoscopy , Animals , Cattle , Cattle Diseases/diagnostic imaging , Cattle Diseases/surgery , Cryptorchidism/diagnostic imaging , Cryptorchidism/surgery , Cryptorchidism/veterinary , Laparoscopy/methods , Laparoscopy/veterinary , Male , Scrotum/diagnostic imaging , Scrotum/surgery , Testis/diagnostic imaging , Testis/surgery , Tomography , Tomography, X-Ray Computed/veterinary
4.
Anat Histol Embryol ; 51(5): 624-632, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35851501

ABSTRACT

Noma horses have the smallest body size among native Japanese horses and are classified as pony breeds by their size. Additionally, the Japanese horse breeds are classified into a single lineage, which includes Mongolian horses. Great intraspecific differences reportedly exist in the head shapes of domesticated horses, which have been investigated in various horse breeds. The present study aimed to evaluate the size of the nasal conchal bullae, and the paranasal sinuses of Noma horses in relation to the skull dimensions using computed tomography. Reconstructed images of the heads of five adult Noma horses were used. Skull and paranasal sinus parameters were measured and analysed in relation to each other and were compared with the data in the literature on the skulls of various horse breeds. In comparison with pony breed, Shetland ponies and donkeys had a shorter nasal length than cranial length, while Noma horses had a longer nasal length than cranial length, similar to the larger breeds. In the nasal conchal bullae, Shetland ponies showed a negative correlation between the head and bullae size, while Noma horses, similar to larger breeds, had a positive correlation. In conclusion, our findings suggest that Noma horses, despite having a body size that belongs to the pony breed, had a distinguishing ratio of the skull and paranasal sinuses similar to that of the larger breeds. Our results provide information on the physiological morphology of the head and comparative anatomy based on genetic diversity in horses.


Subject(s)
Horse Diseases , Noma , Paranasal Sinuses , Animals , Blister/veterinary , Equidae , Head/diagnostic imaging , Horses , Noma/veterinary , Paranasal Sinuses/anatomy & histology , Paranasal Sinuses/diagnostic imaging , Skull/diagnostic imaging
5.
Animals (Basel) ; 11(9)2021 Aug 25.
Article in English | MEDLINE | ID: mdl-34573462

ABSTRACT

In humans, radiation induces dilation of capillaries and inflammatory reactions to raise skin temperature. Thermography is used to detect abnormalities after radiation therapy (RT). However, in veterinary nursing, objective evaluation of the condition of dogs after RT using thermography has not been reported. We investigated the nasal irradiation temperature, behavioral changes, and post-irradiation pain scores in a dog receiving RT for intranasal tumors. The temperature of the nasal planum gradually increased after irradiation, reaching a significantly higher value at 120-240 min. The highest temperature was 42.3 °C and the average temperature increased by 4.4 °C. Behavioral analysis pre- and post-RT did not vary significantly. Post-RT pain levels evaluated by the pain scale ranged from 0 to 1 throughout. No veterinary treatment was provided. In humans, increased skin temperature after radiation causes psychological stress, i.e., pain and discomfort, but no such behavioral changes were observed in this case. Given individual differences in stress-related behaviors, such as pain and discomfort, assessing a dog's painfulness using only subjective methods, such as appearance and behavioral evaluation, is limited. We used thermography to assess changes in conditions not detectable by routine monitoring alone. This method is non-invasive, objective, and indispensable for providing appropriate care.

6.
Vet Sci ; 8(6)2021 Jun 08.
Article in English | MEDLINE | ID: mdl-34201119

ABSTRACT

A 1-year-old female Akita dog was referred for intermittent regurgitation. Computed tomographic angiography (CTA) showed an aberrant right subclavian artery (ARSA), resulting in constriction of the esophagus. After surgical ligation of the ARSA, CTA showed that the ARSA was not enhanced by contrast medium, and that sufficient collateral circulation of the right forelimb was supplied through the vertebral artery. Furthermore, the right and left vertebral arteries merged into the basilar artery at the level of the atlas, and no abnormal expansion of the ventral spinal artery was observed. Overall, we demonstrated the importance of post-surgical CTA for identification of surgical complications, including the formation of abnormal vessel alterations.

7.
Vet Sci ; 7(4)2020 Dec 14.
Article in English | MEDLINE | ID: mdl-33327647

ABSTRACT

A 9-year-old male intact domestic cat weighing 4.6 kg was referred for tachypnea. A large mass was visible in computed tomography (CT) scans of the thoracic cavity. A histopathological evaluation of the mass was consistent with thymoma. The cat was treated with 2 × 8 Gy intensity modulated radiation therapy and sulfoquinovosyl acyl propanediol (SQAP). Post radiation therapy (RT), the tumor structure appeared cystic in the CT, and the tumor volume decreased by approximately 80% after aspiration than that before aspiration. The tumor was removed surgically. RT treatment with SQAP made it possible to treat the thymoma with a low total radiation dose.

8.
Thromb Haemost ; 120(10): 1463-1473, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32746467

ABSTRACT

The effects of antithrombotic therapy on deep vein thrombosis (DVT) can be affected by thrombus age, which cannot be reliably determined by noninvasive imaging modalities. We investigated whether magnetic resonance (MR) diffusion-weighted imaging (DWI) can localize and determine the age of venous thrombus in patients with DVT, animal models, and human blood in vitro. Signal intensity (SI) on DWI and the apparent diffusion coefficient (ADC) of thrombi were assessed in eight patients with DVT using a 1.5-T MR imaging (MRI) system. We assessed the organizing processes as venous thrombus developed in the rabbit jugular vein using a 3.0-T MRI system over time. We also assessed MRI signals of human blood in vitro using the 1.5-T MRI system. Venous thrombi were detected by DWI as areas of high or mixed high and iso SI in all patients. The ADCs were lower in the proximal, than in the distal portion of the thrombi. The thrombi of rabbit jugular veins histologically organized in a time-dependent manner, with high SI on DWI at 4 hours, mixed high and iso SI at 1 and 2 weeks, and iso SI at 3 weeks. The ADC correlated negatively with erythrocyte content, and positively with smooth muscle cells, macrophages, hemosiderin, and collagen content. MRI signals of human blood in vitro showed that ADCs were affected by erythrocyte content, but not by blood clotting. MR-DWI can detect venous thrombus, and high SI on DWI accompanied by a low ADC might reflect erythrocyte-rich, acute-phase thrombi.


Subject(s)
Diffusion Magnetic Resonance Imaging , Venous Thrombosis/diagnostic imaging , Adult , Aged , Aged, 80 and over , Animals , Blood Coagulation , Diffusion Magnetic Resonance Imaging/methods , Disease Models, Animal , Female , Humans , Jugular Veins/diagnostic imaging , Jugular Veins/pathology , Male , Middle Aged , Rabbits , Venous Thrombosis/blood , Venous Thrombosis/pathology , Young Adult
9.
Vet Sci ; 7(3)2020 Jul 13.
Article in English | MEDLINE | ID: mdl-32668593

ABSTRACT

This prospective crossover study compared the effects of intramuscular administration of medetomidine for sedation on parameters of the abdominal vascular system, measured by enhancement computed tomography (CT), to those of propofol-induced sevoflurane maintenance anesthesia, as a control, in five clinically healthy adult male beagle dogs (11.4-12.8 kg). Each animal underwent both protocols at a 1-week interval. The enhancement (HU) and time to peak enhancement on CT were measured for the aorta (AO), caudal vena cava (CVC), portal vein (PV), and hepatic parenchyma (HP). The contrast effects in the AO, PV, and HP were significantly delayed under medetomidine sedation compared to the control anesthesia protocol. Particularly, the contrast effect in the PV and HP was significantly delayed under sedation, appearing approximately 1 min after contrast medium injection. This delay likely reflects the peripheral vasoconstrictive effect of medetomidine. We noted a generally early high contrast enhancement of the CVC under medetomidine sedation, likely contributed by the induced bradycardia. Therefore, findings obtained on contrast enhancement CT under medetomidine sedation may be different from those obtained under propofol-induced sevoflurane maintenance anesthesia. These differences are important to consider when using the findings to inform diagnosis.

10.
Open Vet J ; 10(1): 68-73, 2020 04.
Article in English | MEDLINE | ID: mdl-32426259

ABSTRACT

Background: In humans, visualization of the thoracic duct by magnetic resonance imaging (MRI) has been attempted, and recent advances have enabled clinicians to visualize the thoracic duct configuration in a less invasive manner. Moreover, MRI does not require contrast media, and it enables visualization of morphological details of the thoracic structures. In veterinary practice, the thoracic duct has not been visualized three dimensionally in MRI. Aim: This study aimed to assess the performance of our magnetic resonance thoracic ductography (MRTD) technique to visualize the thoracic duct and the surrounding 3D anatomical structures by combining MRTD and vascular contrast-enhanced thoracic computed tomography (CT) images in dogs. Methods: Five adult male beagle dogs (11.4-12.8 kg) were included in this study. Sagittal and transverse T2-weighted images were scanned in MRI. Scanning in MRTD used a single-shot fast spin echo sequence with a respiratory gate. CT was performed after the intravenous injection of contrast medium. All MRTD and CT images were merged using a workstation. Results: The thoracic ducts were identified in MRTD images of all dogs, and the surrounding anatomical structures were located with the aid of contrast-enhanced thoracic CT. In all dogs, the thoracic ducts coursed along the right-dorsal side of the aorta, cranially from the L2 level. Thereafter, these bent to the left side at the aortic arch and curved at the left external jugular vein angle. A comparison of the number of thoracic ducts at each vertebra between transverse T2WI and MRTD did not reveal any significant differences for all vertebrae. Conclusion: The results from our study suggest that MRTD using the single-shot fast spin echo sequence could be a useful tool for visualization of the thoracic duct. Furthermore, the image merged from MRTD and vascular-enhanced images provided detailed anatomical annotation of the thorax. The MRTD protocol described in this study is safe and easily adaptable, without the need for contrast medium injection into the lymph system. In addition, the images fused from MRTD and vascular contrast-enhanced CT image of the thorax could provide detailed anatomical annotations for preoperative planning.


Subject(s)
Dogs/anatomy & histology , Thoracic Duct/anatomy & histology , Animals , Contrast Media , Imaging, Three-Dimensional/veterinary , Magnetic Resonance Imaging/veterinary , Male , Thoracic Duct/diagnostic imaging , Tomography, X-Ray Computed/veterinary
11.
Ann Thorac Surg ; 109(6): 1692-1699, 2020 06.
Article in English | MEDLINE | ID: mdl-32057812

ABSTRACT

BACKGROUND: The choice between electrocautery or automatic suturing instruments for dissection of the lung parenchyma along the intersegmental plane during lung segmentectomy remains controversial. We hypothesized that a novel microwave surgical instrument (MSI) for dissecting the lung parenchyma could have excellent sealing effects. We examined the feasibility and safety of lung parenchymal dissection using a MSI during lung segmentectomy. METHODS: This was a prospective clinical study of lung segmentectomy involving dissection of the entire intersegmental plane using a MSI. Complications related to sealing of the lung parenchyma were evaluated and perioperative outcomes were compared to those of patients who underwent lung segmentectomy using automatic suturing instruments. Propensity score-matched comparisons were used to assess the potential impact of selection bias. RESULTS: Lung segmentectomy using a MSI was successfully performed in 30 patients. According to the propensity score matching analysis, intraoperative blood loss, length of hospital stay, and postoperative complications of the microwave group were significantly lesser (P = .019, .003, and .008, respectively) compared to those of the control group (n = 66). Prolonged air leakage was not observed. There were two cases of subcutaneous emphysema after removal of the chest tube, but no other grade 2 or higher complications were observed. No mortality occurred within 30 or 90 days postoperatively. CONCLUSIONS: The use of a MSI for lung parenchymal dissection was associated with lower blood loss during surgical procedures, reduced air leakage after the operation, and fewer postoperative complications.


Subject(s)
Pneumonectomy/instrumentation , Pneumonectomy/methods , Aged , Aged, 80 and over , Dissection/methods , Equipment Design , Feasibility Studies , Female , Humans , Lung/surgery , Male , Microwaves/therapeutic use , Middle Aged , Parenchymal Tissue/surgery , Pneumonectomy/adverse effects , Postoperative Complications/epidemiology , Prospective Studies , Radiofrequency Ablation , Suture Techniques/instrumentation , Treatment Outcome
12.
J Clin Biochem Nutr ; 60(1): 76-80, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28163386

ABSTRACT

Multiple free-radical scavenging (MULTIS) activity in cattle and human sera was evaluated with electron spin resonance spectroscopy. Scavenging rates against six active species, namely hydroxyl radical, superoxide anion, alkoxyl radical, alkylperoxyl radical, methyl radical, and singlet oxygen were quantified. The difference in the electron spin resonance signal intensity in the presence and absence of the serum was converted into the scavenging rates. Comparative MULTIS measurements were made in sera from eight beef cattle, three fetal calves and fifteen healthy human volunteers. Further, we determined the MULTIS value of albumin, the most abundant component in serum. MULTIS values in cattle sera indicated higher scavenging activity against most free radical species tested than human sera. In particular, cattle serum scavenging activities against superoxide and methyl radical were higher than human serum by 2.6 and 3.7 fold, respectively. In cattle serum, albumin appears to play a dominant role in MULTIS activity, but in human serum that is not the case. Previous data indicated that the abundance of uric acid in bovine blood is nearly 80% less than humans; however, this difference does not explain the deviation in MULTIS profile.

13.
J Vet Med Sci ; 79(2): 418-424, 2017 Feb 28.
Article in English | MEDLINE | ID: mdl-28025450

ABSTRACT

Fiber tractography is a technique capable of depicting the three-dimensional structure and connectivity of nerve fibers using serial magnetic resonance diffusion tensor imaging (DTI). To establish fiber tractography and DTI methods in veterinary clinical medicine, we evaluated fiber tractography and DTI parameters: apparent diffusion coefficient (ADC) values and fractional anisotropy (FA) values, in various spinal cord diseases. Spinal cord DTI was examined in 28 dogs with spinal cord diseases. The ADC and FA values were measured at lesion sites and cranial normal sites on spinal cords, and both values of lesion sites were compared with normal sites. In thoracolumbar intervertebral disk herniation (IVDH) cases, depending on their neurologic grades, fiber tractography indicated rupture of fiber trajectories, loss of neuronal bundles and disorder of fiber directions. In these cases, the average ADC values at lesion sites significantly decreased compared with normal sites (P=0.016). In the progressive myelomalacia case, the average ADC and FA values of hyperintense swollen regions in T2WI decreased compared to both values in other disease cases. Finally, in the meningioma case, the continuity of fiber trajectories improved after the administration of an anticancer agent. This study suggests that fiber tractography and DTI are useful in the diagnosis and prognosis of veterinary spinal cord diseases.


Subject(s)
Diffusion Tensor Imaging/veterinary , Dog Diseases/diagnostic imaging , Magnetic Resonance Imaging/veterinary , Spinal Cord Diseases/veterinary , Animals , Dogs , Female , Magnetic Resonance Imaging/methods , Male , Meningioma/diagnostic imaging , Meningioma/veterinary , Nerve Fibers , Spinal Cord Diseases/diagnostic imaging
14.
J Vet Med Sci ; 78(3): 451-5, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26522686

ABSTRACT

2.3-month-old (Case 1), one-month-old (Case 2) and 6-month-old (Case 3), Japanese Black calves presented with mild to severe wheezing. All calves had histories of dystocia at birth with breech presentation. Physical examination, thoracic radiography, endoscopy or computed tomography indicated wheezing associated with tracheal collapse and stenosis caused by perinatal rib fractures. Partial resection of the fractured first and second ribs was performed on all calves. The respiration in Cases 1 and 2 immediately improved after the surgery, while Case 3 required two weeks to improve. Cases 1 and 3 grew up healthy and were sold at auction, but Case 2 had a recurrence of wheezing at three months post-discharge and showed growth retarding. Partial costectomy may be an effective solution for control of respiration, however, further cases are required to discuss the criteria for surgical management and to obtain favorable postoperative prognosis in calves with tracheal collapse and stenosis caused by perinatal rib fractures.


Subject(s)
Birth Injuries/veterinary , Cattle Diseases/congenital , Rib Fractures/veterinary , Ribs/surgery , Tracheal Diseases/veterinary , Tracheal Stenosis/veterinary , Animals , Animals, Newborn , Birth Injuries/complications , Birth Injuries/diagnostic imaging , Cattle , Cattle Diseases/diagnostic imaging , Cattle Diseases/etiology , Male , Rib Fractures/complications , Rib Fractures/diagnostic imaging , Rib Fractures/surgery , Tracheal Diseases/diagnostic imaging , Tracheal Diseases/etiology , Tracheal Stenosis/diagnostic imaging , Tracheal Stenosis/etiology
15.
J Vet Med Sci ; 77(5): 631-5, 2015 May.
Article in English | MEDLINE | ID: mdl-25715955

ABSTRACT

Laparoscopic cryptorchidectomy without insufflation was applied in 10 standing bulls aged 3 to 15 months. Nine bulls were preoperatively pointed out intra-abdominal testes by computed tomography. Preoperative fasting for a minimum of 24 hr provided laparoscopic visualization of intra-abdominal area from the kidney to the inguinal region. Surgical procedure was interrupted by intra-abdominal fat and testis size. It took 0.6 to 1.5 hr in 4 animals weighing 98 to 139 kg, 0.8 to 2.8 hr in 4 animals weighing 170 to 187 kg, and 3 and 4 hr in 2 animals weighing 244 and 300 kg to complete the cryptorchidectomy. In conclusion, standing gasless laparoscopic cryptorchidectomy seems to be most suitable for bulls weighing from 100 to 180 kg.


Subject(s)
Cattle Diseases/surgery , Cryptorchidism/veterinary , Laparoscopy/veterinary , Orchiectomy/veterinary , Animals , Cattle , Cryptorchidism/surgery , Laparoscopy/methods , Male , Orchiectomy/methods
16.
Jpn J Radiol ; 32(3): 145-54, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24448965

ABSTRACT

PURPOSE: The purpose of this study was to determine the effect of a synthetic tryptophan metabolite, tranilast [N-(3,4-dimethoxycinnamoyl)-anthranilic acid], on inflammatory and hemorrhagic areas after pulmonary radiofrequency ablation (RFA) in rabbits. MATERIALS AND METHODS: Percutaneous RFA using a 17-gauge LeVeen electrode was performed in normal rabbit lungs. The rabbits were divided into tranilast-treated (300 mg/kg/day, orally) and control groups (n = 24/group). The effects of tranilast were evaluated using multidetector-row computed tomography (CT), histology, and immunohistochemistry immediately after RFA on days 1, 7, 14, and 28. RESULTS: Oral administration of tranilast significantly reduced the size of ablated lesions assessed using CT and histology on days 7 and 14. Furthermore, it reduced the hemorrhagic areas on day 7 and inflammatory areas on day 14, but did not affect the areas of coagulation necrosis on days 1, 7, 14, and 28. Immunohistochemical analysis showed an increase in the ratio of CD163-positive macrophage areas to rabbit macrophage (RAM11)-positive pan-macrophage areas and a decrease in the number of nuclear factor-κB-positive nuclei and CD31-positive microvessels in the tranilast group on days 7 and/or 14. CONCLUSIONS: The results suggest that tranilast modulates the repair process after pulmonary RFA through macrophage accumulation, suppression of inflammation, and angiogenesis.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Catheter Ablation/adverse effects , Hemorrhage/drug therapy , Inflammation/drug therapy , Lung/surgery , ortho-Aminobenzoates/therapeutic use , Animals , Disease Models, Animal , Follow-Up Studies , Hemorrhage/etiology , Inflammation/etiology , Rabbits , Treatment Outcome
17.
BMC Cancer ; 13: 106, 2013 Mar 08.
Article in English | MEDLINE | ID: mdl-23496909

ABSTRACT

BACKGROUND: Glioblastoma is one of the intractable cancers and is highly resistant to ionizing radiation. This radioresistance is partly due to the presence of a hypoxic region which is widely found in advanced malignant gliomas. In the present study, we evaluated the effectiveness of the hypoxic cell sensitizer doranidazole (PR-350) using the C6 rat glioblastoma model, focusing on the status of blood brain barrier (BBB). METHODS: Reproductive cell death in the rat C6 glioma cell line was determined by means of clonogenic assay. An intracranial C6 glioma model was established for the in vivo experiments. To investigate the status of the BBB in C6 glioma bearing brain, we performed the Evans blue extravasation test. Autoradiography with [(14)C]-doranidazole was performed to examine the distribution of doranidazole in the glioma tumor. T2-weighted MRI was employed to examine the effects of X-irradiation and/or doranidazole on tumor growth. RESULTS: Doranidazole significantly enhanced radiation-induced reproductive cell death in vitro under hypoxia, but not under normoxia. The BBB in C6-bearing brain was completely disrupted and [(14)C]-doranidazole specifically penetrated the tumor regions. Combined treatment with X-irradiation and doranidazole significantly inhibited the growth of C6 gliomas. CONCLUSIONS: Our results revealed that BBB disruption in glioma enables BBB-impermeable radiosensitizers to penetrate and distribute in the target region. This study is the first to propose that in malignant glioma the administration of hydrophilic hypoxic radiosensitizers could be a potent strategy for improving the clinical outcome of radiotherapy without side effects.


Subject(s)
Blood-Brain Barrier/drug effects , Brain Neoplasms/radiotherapy , Glioblastoma/radiotherapy , Imidazoles/pharmacology , Radiation-Sensitizing Agents/pharmacology , Animals , Brain Neoplasms/pathology , Cell Death/drug effects , Cell Line, Tumor , Disease Models, Animal , Glioblastoma/pathology , Prospective Studies , Rats
18.
Jpn J Radiol ; 30(4): 323-30, 2012 May.
Article in English | MEDLINE | ID: mdl-22302295

ABSTRACT

PURPOSE: To determine cellular viability of lung parenchyma and neoplastic cells in areas of ground-glass opacity (GGO) on computed tomography (CT) images immediately after pulmonary radiofrequency ablation (RFA) in rabbits. MATERIALS AND METHODS: A LeVeen RFA electrode was placed percutaneously into rabbit lungs with or without metastatic VX2 tumors. Five minutes later, seven isolated lungs were imaged by use of a multi-detector row CT scanner, and the images were compared with histological features. The cellular viability of the lung tissues was assessed by nicotinamide adenine dinucleotide hydrogen (NADH) staining in eight normal lungs and in three lungs with multiple metastatic tumors. RESULTS: All lung lesions appeared as bilayered structures with a central, dense, attenuated area and an outer area of GGO on CT images, and as three-layered structures on macroscopic and microscopic images 5 min after RFA. The GGO areas approximately corresponded to the outer two layers in macroscopic images that were exudative and congestive on microscopic images. Staining for NADH was significantly reduced in the GGO and densely attenuated areas with or without tumor tissue staining compared with the non-ablated area. CONCLUSIONS: Our results suggest that an area of GGO that appears on CT immediately after RFA can be effectively treated by RFA.


Subject(s)
Catheter Ablation/methods , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/surgery , Tomography, X-Ray Computed , Analysis of Variance , Animals , Catheter Ablation/instrumentation , Cell Survival , Equipment Design , Fluoroscopy , Lung Neoplasms/pathology , Prospective Studies , Rabbits , Staining and Labeling
19.
Magn Reson Imaging ; 29(7): 975-84, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21641743

ABSTRACT

Venous thrombus is subsequently organized and replaced by fibrous connective tissue. However, the sequential changes in venous thrombi are not reliably detected by current noninvasive diagnostic techniques. The purpose of this study is to reveal whether magnetic resonance (MR) can detect venous thrombus, define thrombus age and predict thrombolytic responses. Thrombus in the rabbit jugular vein was imaged with a 1.5-T MR system at 4 h and at 1, 2 and 4 weeks using three-dimensional (3D) fast asymmetric spin echo T2-weighted (T2W) and 3D-gradient echo T1-weighted (T1W) sequences. The jugular veins were histologically assessed at each time point. Magnetic resonance imaging (MRI) was also performed in vivo before and 30 min after tissue plasminogen activator (t-PA) administration. The thrombi in MRI were comparable in size to histological sections. The signal intensity (SI) of thrombi at 4 h was heterogeneously high or low on T2W or T1W images, respectively. The SI of thrombi on T2W images decreased time-dependently, but increased on T1W images at 1 and 2 weeks. Morphological analysis showed time-dependent decreases in erythrocyte, platelet and fibrin areas and time-dependent increases in smooth muscle cell, macrophage, collagen and iron areas. The t-PA administration significantly decreased thrombus volume at 4 h but not at 1, 2 and 4 weeks. Venous thrombosis can be reliably and noninvasively detected by MRI. Measurement of SI might support assessments of thrombus age and thrombolytic response.


Subject(s)
Magnetic Resonance Spectroscopy/methods , Thrombosis/pathology , Venous Thrombosis/pathology , Animals , Blood Platelets/cytology , Erythrocytes/cytology , Fibrin/metabolism , Humans , Imaging, Three-Dimensional , Jugular Veins/pathology , Magnetic Resonance Imaging/methods , Male , Rabbits , Signal Processing, Computer-Assisted , Time Factors , Tissue Plasminogen Activator/metabolism
20.
Liver Int ; 31(4): 542-51, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21382165

ABSTRACT

BACKGROUND: The search for effective treatments of non-alcoholic steatohepatitis (NASH), now the most common chronic liver disease in affluent countries, is hindered by a lack of animal models having the range of anthropometric and pathophysiological features as human NASH. AIMS: To examine if mice treated with gold thioglucose (GTG) - known to induce lesions in the ventromedial hypothalamus, leading to hyperphagia and obesity - and then fed a high-fat diet (HF) had a comprehensive histological and dysmetabolic phenotype resembling human NASH. METHODS: C57BL/6 mice were injected intraperitoneally with GTG and then fed HF for 12 weeks (GTG+HF). The extent of abdominal adiposity was assayed by CT scanning. A glucose tolerance test and an insulin tolerance test were performed to evaluate insulin resistance (IR). Histological, molecular and biochemical analyses were also performed. RESULTS: Gold thioglucose+HF induced dysmetabolism, with hyperphagia, obesity with increased abdominal adiposity, IR and consequent steatohepatitis, with hepatocyte ballooning, Mallory-Denk bodies, perivenular and pericellular fibrosis as seen in adult NASH, paralleled by an increased expression of the profibrogenic factors, transforming growth factor-ß1 and TIMP-1. Plasma adiponectin and the expression of adiponectin receptor 1 and receptor 2 were decreased, while PPAR-γ and FAS were increased in the livers of GTG+HF mice. In addition, GTG+HF mice showed glucose intolerance and severe IR. CONCLUSIONS: Treatment with GTG and HF diet induce, in mice, a comprehensive model of human NASH, with the full range of dysmetabolic and histological abnormalities.


Subject(s)
Aurothioglucose/toxicity , Dietary Fats/adverse effects , Disease Models, Animal , Adiponectin/blood , Adipose Tissue/diagnostic imaging , Animals , Aurothioglucose/administration & dosage , Fatty Liver/chemically induced , Fatty Liver/metabolism , Fatty Liver/physiopathology , Glucose Tolerance Test , Hypothalamus/drug effects , Injections, Intraperitoneal , Insulin Resistance/physiology , Liver/metabolism , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease , PPAR gamma/metabolism , Receptors, Adiponectin/metabolism , Statistics, Nonparametric , Tomography, X-Ray Computed
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