[Show abstract][Hide abstract] ABSTRACT: Leptospirosis is an important zoonotic disease diffused worldwide, and wildlife species are commonly considered to be important epidemiological carriers. Four-hundred and forty-one serological and 198 renal samples from red deer, roe deer and chamois collected in the Province of Sondrio were analysed using the microscopic agglutination test and histopathologic examination. Positive serological findings were found only in 15 red deer and 19 positive serologic reactions were recorded. The most frequent serovars were Bratislava and Grippotyphosa, followed by Pomona, Hardjo and Copenhagheni. Twenty-two per cent of renal samples from seropositive red deer were affected by mild to moderate multifocal chronic lymphoplasmacytic and fibrosing tubulo-interstitial nephritis, mainly involving the cortical parenchyma. In this study, antibodies to Leptospira spp. were infrequent in wild ruminants, and only red deer seemed to be sensitive to the infection. Given the low presence and the fact that there was no record of Leptospira spp. infections in cattle, sheep, goats and also hunters in area during the study period, wild ruminants in Alpine environments cannot be considered as reservoirs or important sources of Leptospira spp. infection for humans or domestic animals.
Veterinaria italiana 12/2014; 50(4):285-91. · 0.68 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Ringtail is a pathologic condition of laboratory rodents characterized by annular constrictions of the tail. Traditionally, it is classified as an environmental disorder caused by low relative humidity, but other factors (temperature, dietary deficiencies, genetic susceptibility, and caging type) have also been proposed. Twenty litters of mice with ringtail lesions occurred from September 2010 to August 2013 in a facility located in the northern Italy. Mice were maintained under controlled environmental conditions and fed a standard diet. Retrospective analysis of environmental data (relative humidity, temperature) was carried out. Gross, histopathologic, scanning, and transmission electron microscopy examination of tails and limbs was performed. The incidence of ringtail was 0.075% (20/26 800) of all weaned litters over the 3-year period of examination. Temperature and relative humidity remained within accepted limits in all cases except one. We observed annular constrictions in tail, digits of pes, crus, and antebrachium in 116 (100.0%), 47 (40.5%), 11 (9.5%), and 2 (1.7%) of 116 affected mice, respectively. Histologic and ultrastructural examination revealed abnormal keratin desquamation and presence of a keratin ring encircling the tail, causing progressive strangulation of the growing tail with subsequent compression and ulceration of underlying soft tissues, resulting in circulatory changes (edema, hyperemia, thrombosis, hemorrhages), ischemic necrosis, and eventually auto-amputation distal to the constriction. On the basis of our findings, we suggest a disorder of cornification as the primary lesion of ringtail in mice. The cause of these cases, however, remained undetermined, even though traditional etiologic factors (relative humidity, temperature, diet, caging type) were reasonably excluded.
[Show abstract][Hide abstract] ABSTRACT: p53 influences genomic stability, apoptosis, autophagy, response to stress, and DNA damage. New p53-target genes could elucidate mechanisms through which p53 controls cell integrity and response to damage.
DRAGO (drug-activated gene overexpressed, KIAA0247) was characterized by bioinformatics methods as well as by real-time polymerase chain reaction, chromatin immunoprecipitation and luciferase assays, time-lapse microscopy, and cell viability assays. Transgenic mice (94 p53(-/-) and 107 p53(+/-) mice on a C57BL/6J background) were used to assess DRAGO activity in vivo. Survival analyses were performed using Kaplan-Meier curves and the Mantel-Haenszel test. All statistical tests were two-sided.
We identified DRAGO as a new p53-responsive gene induced upon treatment with DNA-damaging agents. DRAGO is highly conserved, and its ectopic overexpression resulted in growth suppression and cell death. DRAGO(-/-) mice are viable without macroscopic alterations. However, in p53(-/-) or p53(+/-) mice, the deletion of both DRAGO alleles statistically significantly accelerated tumor development and shortened lifespan compared with p53(-/-) or p53(+/-) mice bearing wild-type DRAGO alleles (p53(-/-), DRAGO(-/-) mice: hazard ratio [HR] = 3.25, 95% confidence interval [CI] = 1.7 to 6.1, P < .001; p53(+/-), DRAGO(-/-) mice: HR = 2.35, 95% CI = 1.3 to 4.0, P < .001; both groups compared with DRAGO(+/+) counterparts). DRAGO mRNA levels were statistically significantly reduced in advanced-stage, compared with early-stage, ovarian tumors, but no mutations were found in several human tumors. We show that DRAGO expression is regulated both at transcriptional-through p53 (and p73) and methylation-dependent control-and post-transcriptional levels by miRNAs.
DRAGO represents a new p53-dependent gene highly regulated in human cells and whose expression cooperates with p53 in tumor suppressor functions.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to identify, by magnetic resonance imaging (MRI), the ability of the blood-pool contrast agent B22956/1 to detect atherosclerotic plaques developing at the brachiocephalic artery of apolipoprotein E knockout (apoE-KO) mice and to possibly identify vulnerable atherosclerotic lesions. After high-fat feeding for 8 or 12 weeks, MRIs of brachiocephalic arteries were acquired before and after B22956/1 administration; then vessels were removed and analyzed by histology. B22956/1 injection caused a rapid increase in plaque signal enhancement and plaque to muscle contrast values, which remained stable up to 70 minutes. A linear correlation between signal enhancement and macrophage content was found 10 minutes after B22956/1 injection (p < .01). Signal enhancement and plaque to muscle contrast values correlated with macrophage content 40 minutes after contrast agent administration (p < .01). Finally, 70 minutes after B22956/1 infusion, plaque to muscle contrast significantly correlated with the percentage of stenosis (p < .005). B22956/1 administration to high fat-fed apoE-KO mice resulted in a rapid enhancement of atherosclerotic plaques and in a great ability to rapidly visualize vulnerable plaques, characterized by a high macrophage content. These results suggest that B22956/1 could represent an interesting tool for the identification of atherosclerotic plaques potentially leading to acute cardiovascular events.
[Show abstract][Hide abstract] ABSTRACT: Context:Tyrosine kinase inhibitors (TKI) represent a new treatment option for patients with advanced medullary thyroid cancer (MTC). However, cures have not been achieved with current available agents used in monotherapy.Objective:Since RET has been shown to negatively regulate CD95 death receptor activation in preclinical models of RET-dependent MTC, we investigated the potential of the combination approach with the RET targeting TKI sunitinib and cisplatin to enhance apoptosis activation through the extrinsic pathway.Design:The effects of sunitinib and cisplatin were examined in human MTC cell lines harboring oncogenic RET mutations. Experiments were designed to determine drug effects on RET signaling, cell growth, apoptosis, autophagy, tumor growth in mice, and to investigate the mechanisms of the drug interaction.Results:Sunitinib and cisplatin synergistically inhibited the growth of MZ-CRC-1 cells harboring the RET M918T activating mutation. The combination enhanced apoptosis activation through CD95-mediated, caspase-8 dependent, pathway. Moreover, sunitinib induced a severe perturbation of the autophagic flux characterized by autophagosome accumulation and a remarkable lysosomal dysfunction which was further enhanced, with lysosomal leakage induction, by cisplatin. Administration of the drug combination to mice xenografted with MZ-CRC-1 cells improved the antitumor efficacy, as compared to single agent treatments, inducing complete responses in 30% of treated mice, a significant increase in caspase-3 activation (P < 0.01 vs cisplatin, P < 0.0005 vs sunitinib) and apoptosis in tumor cells.Conclusions:Addition of cisplatin to sunitinib potentiates apoptotic cell death and has promising preclinical activity in MTCs harboring the RET M918T oncogene.
The Journal of Clinical Endocrinology and Metabolism 11/2013; · 6.31 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Treatment of ovarian carcinoma often fails to be curative due to drug resistance and many efforts are directed to overcome tumor cell resistance by increasing apoptosis induction. The potential of Second mitochondria-derived activator of caspases (SMAC) mimetics (SMACm) has appeared in preclinical studies, but novel pro-apoptotic agents of this class with improved pharmacological profile are needed. To identify novel treatment options for ovarian carcinoma by interfering with anti-apoptotic factors, in the present study, a novel homodimeric SMACm (SM83) was employed in preclinical models, both in vitro and in vivo. An investigation of the structural features of dimeric SM83 as compared to a closely related reference compound indicated slight differences, likely due to the interaction between one of the terminal phenyl groups and triazole rings of SM83 with the BIR2 domain. Although SM83 per se did not inhibit cell proliferation, it displayed a synergistic effect in combination with TNF-related apoptosis inducing ligand (TRAIL) in cell sensitivity assays. Since the tumor microenviroment is a reservoir of cytokines that may act in conjunction with SMACm to affect tumor growth, the activity of the novel compound was tested in vivo in ovarian carcinoma cells subcutaneously xenografted in immuno-deficient mice. A significant tumor volume inhibition was observed together with activation of caspase 3 and of apoptotic cell death. A biochemical analysis of Tumor Necrosis Factor (TNF) and TRAIL content in specimens from xenografted mice indicated that SM83 down-modulated the levels of human TNF in plasma samples and tended to up-modulate human TRAIL levels in tumors. Thus, TRAIL appears to contribute to the antitumor activity of the novel SMACm SM83 in subcutaneously grown ovarian carcinoma. Overall, our results indicate SM83 as an attractive candidate for further development.
[Show abstract][Hide abstract] ABSTRACT: Effects of post-resuscitation treatment with argon on neurological recovery were investigated in a porcine model of cardiac arrest (CA) with an underlying acute myocardial infarction.
The left anterior descending coronary artery (LAD) was occluded in 12 pigs and CA was induced. After 8 min of untreated CA, cardiopulmonary resuscitation was performed for 5 min prior to defibrillation. Following resuscitation, animals were subjected to 4 hr ventilation with 70% argon/30% oxygen or 70% nitrogen/30% oxygen. Myocardial function was echocardiographically assessed and serum neuron specific enolase (NSE) was measured. Animals were observed up to 72 hr for assessment of survival and neurological recovery.
All the animals were resuscitated and survived for 72 hr, except for a control pig. Ventilation with argon did not have any detrimental effects on hemodynamics and respiratory gas exchange. All the 6 argon treated animals had a fast and complete 72 hr neurological recovery, in contrast to only 2 of the 6 controls (p < 0.05). Seventy-two hr neurological alertness score and neurological deficit score were respectively 100 and 0 in the argon group and 79 and 29 in the control one (p < 0.01 and p < 0.05). Significantly lower increases in serum NSE (12% vs. 234%) and minimal histological brain injury (neuronal degeneration: 0 vs. 1) were also observed in argon treated animals, in comparison to controls.
In this model, post-resuscitation treatment with argon allowed for a faster and complete neurological recovery, without detrimental effects on hemodynamics and respiratory gas exchanges.
[Show abstract][Hide abstract] ABSTRACT: The development of resistance and progressive disease after treatment with angiogenesis inhibitors is becoming a controversial issue. We investigated the experimental conditions that cause multikinase receptor inhibitors (RTKI) to augment metastasis and whether opportune combinations with chemotherapy could counteract this effect. The renal Renca-luc tumor was transplanted orthotopically in the kidney of Balb/c mice, which were then or not nephrectomized. The Lewis Lung carcinoma (LLC) was transplanted in the tibial muscle of C57/Bl6 mice. Treatment with the RTKI sunitinib started at different stages of tumor progression, mimicking neo-adjuvant or adjuvant settings. Combination studies with paclitaxel, doxorubicin, cisplatin, gemcitabine and topotecan were done on the LLC model, using opportune regimens. In a neo-adjuvant setting sunitinib inhibited Renca-luc tumor growth, prolonging survival despite an increase in lung metastasis; treatment after primary tumor surgery (adjuvant setting) or on established metastasis prolonged survival and decreased metastasis. Sunitinib increased lung metastasis from mice bearing early-stage LLC, but did not affect established metastases (no acceleration) from advanced tumors. Combinations with doxorubicin, topotecan, gemcitabine, but not cisplatin and paclitaxel, counteracted the increase in metastasis from LLC, partly reflecting their antitumor activity. Histology analysis after sunitinib confirmed tumor vascular changes and increased hypoxia. Topotecan at suboptimal daily doses reduced sunitinib-related metastasis, reducing tumor hypoxia. Tyrosin kinase inhibitors, as sunitinib, can have adverse malignant effects mainly in the neo-adjuvant setting. The addition of chemotherapy might influence metastasis, depending on each drug mechanism of action and its regimen of administration.
Molecular Cancer Therapeutics 08/2013; · 5.60 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A small library of integrin ligand - Paclitaxel conjugates 10-13 was synthesized with the aim of using the tumor-homing cyclo[DKP-RGD] peptidomimetics for site-directed delivery of the cytotoxic drug. All the Paclitaxel-RGD constructs 10-13 inhibited biotinylated vitronectin binding to the purified α(V)β(3) integrin receptor at low nanomolar concentration and showed in vitro cytotoxic activity against a panel of human tumor cell lines similar to that of Paclitaxel. Among the cell lines, the cisplatin-resistant IGROV-1/Pt1 cells expressed high levels of integrin α(V)β(3), making them attractive to be tested in in vivo models. Cyclo[DKP-f3-RGD]-PTX 11 displayed sufficient stability in physiological solution and in both human and murine plasma to be a good candidate for in vivo testing. In tumor-targeting experiments against the IGROV-1/Pt1 human ovarian carcinoma xenotransplanted in nude mice, compound 11 exhibited a superior activity than Paclitaxel, despite the lower (ca. half) molar dosage used.
Journal of Medicinal Chemistry 11/2012; · 5.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: An 18-month-old male basset hound was presented with vomiting, diarrhoea and depression. Abdominal ultrasonography revealed a mass in the left kidney. An ultrasound-guided core-biopsy indicated aggregates of spindle cells, but did not allow a definitive diagnosis. Nephrectomy was performed after a period of six months, when ultrasound examination revealed a slight increase in mass dimensions. Histologically the mass was composed of neoplastic spindle cells forming interlacing fascicles, bundles and whorls, within a loose myxoid to dense collagenous stroma. Immunohistochemically neoplastic cells were positive for vimentin and smooth muscle actin. Based on these findings the tumour was diagnosed as a congenital mesoblastic nephroma, classical variant. After a two-and-a-half-year follow-up the dog was clinically healthy, indicating a benign behaviour. To the authors' knowledge, this report describes the first case of canine congenital mesoblastic nephroma successfully treated surgically, with a reasonable postsurgical follow-up.
Journal of Small Animal Practice 10/2012; · 0.91 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The efficacy of taxane-based antitumor therapy is limited by several drawbacks which result in a poor therapeutic index. Thus, the development of approaches that favor selective delivery of taxane drugs (e.g., paclitaxel, PTX) to the disease area represents a truly challenging goal. On the basis of the strategic role of integrins in tumor cell survival and tumor progression, as well as on integrin expression in tumors, novel molecular conjugates were prepared where PTX is covalently attached to either cyclic AbaRGD (Azabicycloalkane-RGD) or AmproRGD (Aminoproline-RGD) integrin-recognizing matrices via structurally diverse connections. Receptor-binding assays indicated satisfactory-to-excellent α(V)β(3) binding capabilities for most conjugates, while in vitro growth inhibition assays on a panel of human tumor cell lines revealed outstanding cell sensitivity values. Among the nine conjugate ensemble, derivative 21, bearing a robust triazole ring connected to ethylene glycol units by an amide function and showing excellent cell sensitivity properties, was selected for in vivo studies in an ovarian carcinoma model xenografted in immunodeficient mice. Remarkable antitumor activity was attained, superior to that of PTX itself, which was associated with a marked induction of aberrant mitoses, consistent with the mechanism of action of spindle poisons. Overall, the novel cRGD-PTX conjugates disclosed here represent promising candidates for further advancement in the domain of targeted antitumor therapy.
[Show abstract][Hide abstract] ABSTRACT: Bevacizumab is being incorporated as first-line therapy with standard-of-care chemotherapy on epithelial ovarian carcinoma (EOC). We investigated bevacizumab combined with chemotherapy on tumour progression and mouse survival in EOC xenograft models.
Bevacizumab was administered concomitantly with cisplatin plus paclitaxel (DDP+PTX), continued after induction (maintenance) or started after chemotherapy. The effect on tumour progression was monitored by bioluminescence imaging (BLI) (1A9-luc xenograft). Tumour dissemination into the peritoneal organs and ascites formation (HOC22 xenograft) was evaluated by histological analysis at the end of treatment (interim) and at euthanasia (survival). The effects on overall survival (OS) were investigated in both EOC models.
Bevacizumab with PTX+DDP delayed tumour progression in mice bearing EOC xenografts. OS was significantly extended, with complete responses, by bevacizumab continued after stopping chemotherapy in the HOC22 xenograft. Bevacizumab alone inhibited ascites formation, with only limited effect on tumour burden, but combined with PTX+DDP reduced ascites and metastases. Bevacizumab started after induction with PTX+DDP and maintained was equally effective on tumour progression and survival on 1A9-luc xenograft.
Bevacizumab combined with chemotherapy not only affected tumour progression, but when administered as maintenance regimen significantly prolonged survival, reducing ascites, and tumour dissemination. We believe our findings are consistent with the clinical results and shed light on the potential effects of this kind of treatment on tumour progression.
British Journal of Cancer 06/2012; 107(2):360-9. · 5.08 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Introduction: "Tissue-selective estrogen complex" or TSEC is a novel concept of estrogen replacement therapy for the postmenopause based on the combined use of estrogens and selective estrogen receptor modulators (SERMs). The aim of this study was to exploit the potential of a novel transgenic mouse where luciferase expression is associated with cell proliferation (the MITO-luc mouse) to investigate cell proliferation in reproductive and nonreproductive tissues in mice exposed to repetitive treatments with TSEC. Material and Methods: Ovariectomized MITO-Luc mice were subjected to a daily oral treatment with bazedoxifene, conjugated estrogen (CE), TSEC, or raloxifene for 21 days. During the treatment, the proliferative effects of treatments were monitored by bioluminescence-based in vivo imaging. At the end of the treatment, mice were euthanized and cell proliferation assessed in selected tissues by quantitative analysis of luciferase activity and by immunohistochemistry (IHC). Results: In uterus treatment with CE, but not TSEC, induced a large increase in luciferase activity underlying the proliferative effect of the hormone. No accumulation of luciferase was observed in other organs and tissues target of estrogen action. We observed an increase of Ki67 immunoreactivity only in the uterus of mice treated with CE. Conclusion: Pairing of an SERM with estrogens results in a complete blockage of CE proliferative effects in uterus and the absence of any undesired proliferative effects in other organs; moreover, the MITO-Luc mouse is an efficacious tool for the global, rapid, and reliable analysis of drug-induced proliferation.
[Show abstract][Hide abstract] ABSTRACT: Enterohepatic Helicobacter spp. have been described colonizing the large intestine and liver of healthy and symptomatic subjects and are thought to have a role in the development of inflammatory bowel disease (IBD). The prevalence of enterohepatic Helicobacter spp. infection in dogs is largely unknown and to our knowledge there are no data about their potential pathogenic role. In light of these considerations, the aims of this study were (i) to assess the prevalence of enterohepatic Helicobacter spp. in colonic biopsies of symptomatic pet dogs and (ii) to evaluate a possible association between Helicobacter spp. colonization status (heavily colonized, poorly colonized and uncolonized biopsies) and histological lesions. Colonic biopsies from 27 pet dogs of different ages were evaluated by family Helicobacteraceae and enterohepatic Helicobacter spp. PCR, histology, and immunohistochemistry for the in situ detection of Helicobacter spp. organisms. 85% and 52% of colonic biopsies were positive by Helicobacteraceae and enterohepatic Helicobacter spp. PCR, respectively. Immunohistochemistry revealed Helicobacter spp. were localized both in the superficial mucus (55%) and within intestinal crypts (33%). Dogs with heavy enterohepatic Helicobacter spp. colonization were significantly younger and had a higher level of mucosal fibrosis/atrophy than dogs with uncolonized or poorly colonized biopsies (p<0.05). These findings contribute to widen current knowledge regarding canine enterohepatic Helicobacter spp., suggesting the infection is rather common in dogs and acquired at an early age. Furthermore, heavy colonization of colonic crypts is associated with chronic inflammatory lesions (fibrosis/atrophy), supporting the role of enterohepatic Helicobacter spp. in the development of canine IBD.
[Show abstract][Hide abstract] ABSTRACT: Giant cell tumor of bone (GCTB) is a common primary neoplasm of bone characterized by distinctive clinicopathological features. GCTB is exceedingly rare in nonhuman species, and it has been sporadically reported in cats, dogs, rats, and birds. This report describes a primary murine bone tumor that shares striking clinicopathological similarities with human GCTB. The neoplasm occurred in a 71-week-old C57BL/6 mouse heterozygous for the specific Trp53 R172H point mutation. Grossly, the tumor presented as a mono-ostotic nodular mass arising from the distal metaphysis of the right femur. Microscopically, the affected bone was effaced by an osteolytic neoplasm with focal infiltrations into the surrounding tissues. Similarly to what was reported for human GCTB, the murine neoplasm consisted of 3 main cell populations: (1) bundles of pleomorphic spindle-shaped mononuclear cells displaying an indefinite mesenchymal histogenesis with immunohistochemical expression of vimentin and smooth muscle actin, (2) scattered multinucleated giant cells exhibiting osteoclast differentiation with prominent tartrate-resistant acid phosphatase activity and immunoreactivity for monocyte/macrophage markers including CD45 and lysozyme, and (3) scattered round mononuclear cells consistent with activated macrophages and expressing CD45, lysozyme, and F4/80. Based on these morphological and immunohistological results, the murine bone tumor described in this study has been putatively classified as GCTB.
[Show abstract][Hide abstract] ABSTRACT: The study was designed to evaluate anti-tumour properties of Iraqi propolis collected from Mosul region (M) on HL-60 and HCT-116 cell lines and on HCT-116 in vivo. M induced an inhibitory effect against the proliferation of HL-60 and colony potential of HCT-116 cells. The apoptosis in HL-60 cells was associated with down-regulation of Bcl-2 and activation of Bax, while in HCT-116 cells, necrotic features were observed; size of cells was dramatically increased by swelling of cytoplasm and loss of membrane integrity, cell rupture and release of cellular contents. Analysis of BrdU/DNA cell cycle in both cell lines showed that M induced cell cycle perturbations in both BrdU positive and BrdU negative cells. The exposure of HL-60 to M caused γ-H2AX in a dose dependent manner and was associated with induction of apoptosis. The experiments in HCT-116 tumor-bearing mice showed that oral administration of propolis at doses that caused no detectable toxicity was associated with a decrease in mitotic cells and an increase in endoreduplications, increased p53 and decreased Ki-67 expression of cells in tumor sections. This study provides the rationale to investigate the potential beneficial effect of propolis in the diet of patients receiving anti-cancer therapies.
Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 01/2012; 50(5):1632-41. · 2.99 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Tertiary lymphoid organs (TLOs) are structures that are morphologically and functionally similar to secondary lymphoid organs. TLOs usually arise in a background of chronic inflammation. Several histological patterns of interstitial nephritis have been documented in porcine leptospirosis. Among them the lympho-follicular pattern is characterized by infiltrates of mononuclear cells organized in lymphoid follicle-like structures. Immunohistological analysis of 5 cases of porcine lympho-follicular nephritis associated with Leptospira Pomona infection demonstrated the presence of inflammatory cell populations, including B cells, T cells, macrophages and follicular dendritic cells (FDCs), which were compartmentalized as in TLOs. Immunohistochemistry for Leptospira Pomona revealed an intimate association between leptospiral antigen and FDCs. Overexpression of MHCII in different populations of both professional and non-professional antigen presenting cells was also demonstrated. FDCs play role during TLOs induction for their ability to retain non-self antigens in the form of immune complexes, thus causing persistent T cell activation, generation of a complex cytokine network and stimulation of humoral immunity. Sustained bacterial antigen presentation in the context of chronic leptospiral nephritis, may also lead to autoimmune mechanisms involved in the generation of TLOs. Whether lymphoid neogenesis and TLOs play a protective role in porcine leptospiral nephritis is still unclear.
Veterinary Immunology and Immunopathology 01/2012; 145(1-2):546-50. · 1.75 Impact Factor