Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 32
Filter
1.
Sci Data ; 10(1): 427, 2023 07 03.
Article in English | MEDLINE | ID: mdl-37400466

ABSTRACT

Systematic and timely documentation of triggered (i.e. event) landslides is fundamental to build extensive datasets worldwide that may help define and/or validate trends in response to climate change. More in general, preparation of landslide inventories is a crucial activity since it provides the basic data for any subsequent analysis. In this work we present an event landslide inventory map (E-LIM) that was prepared through a systematic reconnaissance field survey in about 1 month after an extreme rainfall event hit an area of about 5000 km2 in the Marche-Umbria regions (central Italy). The inventory reports evidence of 1687 triggered landslides in an area of ~550 km2. All slope failures were classified according to type of movement and involved material, and documented with field pictures, wherever possible. The database of the inventory described in this paper as well as the collection of selected field pictures associated with each feature is publicly available at figshare.

2.
Soc Indic Res ; 162(3): 1233-1260, 2022.
Article in English | MEDLINE | ID: mdl-35125614

ABSTRACT

To achieve the UN 2030 Agenda Goals, and considering their complexity and multidisciplinary, Multi-criteria analysis appears to be a suitable approach to give a true support to public decision makers in defining policy lines. This study focuses on the application of the Multiple Reference Point Weak-Strong Composite Indicators (MRP-WSCI) and its partially compensatory version (MRP-PCI), to assess, in the framework of the UN 2030 Agenda, the sustainability of the 28 members of the European Union (pre-Brexit). Countries were analyzed and compared according to their conditions and progress against the 17 Sustainable Development Goals, considering three reference years: 2007, 2012 and 2017. The analysis shows that Nordic countries reach a good level of global sustainability, with values of the indicators, W-W-W and S-W-W, between 2 and 3; while the States of east Europe, in particular Romania, Bulgaria and Greece, stay at the worst levels, having overall indicators values less than 1.5. Furthermore, the results highlight how countries in the lower group have difficulties especially in social and economic sustainability. On the other hand, states with a good overall condition record the worst results in the environmental dimension, such as the Netherlands, which shows, for the year 2017, a value for this sphere less than 2, while in the other two show a good value (over 2.5).

3.
J R Soc Interface ; 19(187): 20210642, 2022 02.
Article in English | MEDLINE | ID: mdl-35104431

ABSTRACT

Bone has a sophisticated architecture characterized by a hierarchical organization, starting at the sub-micrometre level. Thus, the analysis of the mechanical and structural properties of bone at this scale is essential to understand the relationship between its physiology, physical properties and chemical composition. Here, we unveil the potential of Brillouin-Raman microspectroscopy (BRaMS), an emerging correlative optical approach that can simultaneously assess bone mechanics and chemistry with micrometric resolution. Correlative hyperspectral imaging, performed on a human diaphyseal ring, reveals a complex microarchitecture that is reflected in extremely rich and informative spectra. An innovative method for mechanical properties analysis is proposed, mapping the intermixing of soft and hard tissue areas and revealing the coexistence of regions involved in remodelling processes, nutrient transportation and structural support. The mineralized regions appear elastically inhomogeneous, resembling the pattern of the osteons' lamellae, while Raman and energy-dispersive X-ray images through scanning electron microscopy show an overall uniform distribution of the mineral content, suggesting that other structural factors are responsible for lamellar micromechanical heterogeneity. These results, besides giving an important insight into cortical bone tissue properties, highlight the potential of BRaMS to access the origin of anisotropic mechanical properties, which are almost ubiquitous in other biological tissues.


Subject(s)
Bone and Bones , Haversian System , Anisotropy , Bone and Bones/diagnostic imaging , Cortical Bone , Haversian System/physiology , Humans , Microscopy, Electron, Scanning , Spectrum Analysis, Raman/methods
4.
Sci Rep ; 10(1): 17341, 2020 10 15.
Article in English | MEDLINE | ID: mdl-33060731

ABSTRACT

Brillouin-Raman microspectroscopy is presented as an innovative label-free all-optical investigation approachable to characterize the chemical composition and the mechanical properties of human tissues at micrometric resolution. Brillouin maps unveil mechanical heterogeneities in a human femoral diaphysis, showing a ubiquitous co-existence of hard and soft components, even in the most compact sections. The novel correlative analysis of Brillouin and Raman maps shows that the relative intensity of Brillouin peaks is a good proxy for the fraction of mineralized fibers and that the stiffness (longitudinal elastic modulus) of the hard component is linearly dependent on the hydroxyapatite concentration. For the soft component, a gradient of composition is found, ranging from an abundance of proteins in the more compact, external, bone to abundance of lipids, carotenoids, and heme groups approaching the trabecular, inner, part of the diaphysis. This work unveils the strong potential of correlative mechano-chemical characterization of human tissues at a micrometric resolution for both fundamental and translational research.


Subject(s)
Diaphyses/chemistry , Femur/chemistry , Spectrum Analysis, Raman/methods , Biomechanical Phenomena , Elastic Modulus , Humans , Translational Research, Biomedical
5.
Biomed Opt Express ; 10(5): 2606-2611, 2019 May 01.
Article in English | MEDLINE | ID: mdl-31143505

ABSTRACT

Brillouin micro-spectroscopy is applied for investigating the mechanical properties of bone and cartilage tissues of a human femoral head. Distinctive mechanical properties of the cartilage surface, subchondral and trabecular bone are reported, with marked heterogeneities at both micrometric and millimetric length scales. A ubiquitous soft component is reported for the first time, characterized by a longitudinal modulus of about 4.3 GPa, possibly related to the amorphous phase of the bone. This phase is mixed, at micrometric scales, with a harder component, ascribed to mineralized collagen fibrils, characterized by a longitudinal modulus ranging between 16 and 25 GPa.

6.
Biophys Chem ; 229: 123-129, 2017 10.
Article in English | MEDLINE | ID: mdl-28684254

ABSTRACT

Mechanical mapping with chemical specificity of biological samples is now made possible by joint micro-Brillouin and micro-Raman measurements. In this work, thanks to the unprecedented contrast of a new tandem Fabry-Perot interferometer, we demonstrate simultaneous detection of Brillouin and Raman spectra from different Candida biofilms. Our proof-of-concept study reveals the potential of this label-free joint micro-spectroscopy technique in challenging microbiological issues. In particular, heterogeneous chemo-mechanical maps of Candida biofilms are obtained, without the need for staining or touching the sample. The correlative Raman and Brillouin investigation evidences the role of both extracellular polymeric substances and of hydration water in inducing a marked local softening of the biofilm.


Subject(s)
Biofilms , Candida/chemistry , Microbiological Techniques/methods , Microspectrophotometry , Spectrum Analysis, Raman , Candida/physiology , Elastic Modulus , Microbiological Techniques/instrumentation , Viscosity
7.
J Vet Intern Med ; 31(2): 492-497, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28238221

ABSTRACT

BACKGROUND: Spinal walking (SW) is described as the acquisition of an involuntary motor function in paraplegic dogs and cats without pain perception affected by a thoracolumbar lesion. Whereas spinal locomotion is well described in cats that underwent training trials after experimental spinal cord resection, less consistent information is available for dogs. HYPOTHESIS: Paraplegic dogs affected by a thoracolumbar complete spinal cord lesion undergoing intensive physical rehabilitation could acquire an autonomous SW gait under field conditions. ANIMALS: Eighty-one acute paraplegic thoracolumbar dogs without pelvic limb pain perception. METHODS: Retrospective study of medical records of dogs selected for intensive rehabilitation treatment in paraplegic dogs with absence of pain perception on admission and during the whole treatment. Binary regression and multivariate logistic regression were used to analyze potential associations with the development of SW. RESULTS: Autonomous SW was achieved in 48 dogs (59%). Median time to achieve SW was of 75.5 days (range: 16-350 days). On univariate analysis, SW gait was associated with younger age (P = .002) and early start of physiotherapy (P = .024). Multivariate logistic regression showed that younger age (≤60 months) and lightweight (≤7.8 kg) were positively associated with development of SW (P = .012 and P < .001, respectively). BCS, full-time hospitalization, and type and site of the lesion were not significantly associated with development of SW. CONCLUSIONS: Dogs with irreversible thoracolumbar lesion undergoing intensive physiotherapic treatment can acquire SW. Younger age and lightweight are positively associated with the development of SW gait.


Subject(s)
Dog Diseases/therapy , Paraplegia/veterinary , Physical Therapy Modalities/veterinary , Spinal Cord Injuries/veterinary , Age Factors , Animals , Body Weight , Dogs , Female , Gait , Hindlimb/physiopathology , Male , Paraplegia/rehabilitation , Retrospective Studies , Spinal Cord Injuries/rehabilitation , Walking
8.
Phys Med ; 32(12): 1659-1666, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27765457

ABSTRACT

PURPOSE: To predict patients who would benefit from adaptive radiotherapy (ART) and re-planning intervention based on machine learning from anatomical and dosimetric variations in a retrospective dataset. MATERIALS AND METHODS: 90 patients (pts) treated for head-neck cancer (H&N) formed a multicenter data-set. 41 H&N pts (45.6%) were considered for learning; 49 pts (54.4%) were used to test the tool. A homemade machine-learning classifier was developed to analyze volume and dose variations of parotid glands (PG). Using deformable image registration (DIR) and GPU, patients' conditions were analyzed automatically. Support Vector Machines (SVM) was used for time-series evaluation. "Inadequate" class identified patients that might benefit from replanning. Double-blind evaluation by two radiation oncologists (ROs) was carried out to validate day/week selected for re-planning by the classifier. RESULTS: The cohort was affected by PG mean reduction of 23.7±8.8%. During the first 3weeks, 86.7% cases show PG deformation aligned with predefined tolerance, thus not requiring re-planning. From 4th week, an increased number of pts would potentially benefit from re-planning: a mean of 58% of cases, with an inter-center variability of 8.3%, showed "inadequate" conditions. 11% of cases showed "bias" due to DIR and script failure; 6% showed "warning" output due to potential positioning issues. Comparing re-planning suggested by tool with recommended by ROs, the 4th week seems the most favorable time in 70% cases. CONCLUSIONS: SVM and decision-making tool was applied to overcome ART challenges. Pts would benefit from ART and ideal time for re-planning intervention was identified in this retrospective analysis.


Subject(s)
Machine Learning , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Computer-Assisted/methods , Cohort Studies , Humans , Reproducibility of Results , Retrospective Studies
9.
Ann N Y Acad Sci ; 1040: 320-2, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15891051

ABSTRACT

Numerous studies have described the presence of an intragonadal IGF system involved in regulation of gametogenesis in teleost fish. In the present study, the in vivo effects of estradiol-17beta (E2) and growth hormone (GH) exposure on IGF-I, IGF-II, IGF1R, and IGFBP2 gene expression in sea bream ovary were monitored by RT-PCR during prereproductive and reproductive periods. The evidence demonstrates that both hormones investigated here affect the ovarian IGF system, showing that it is not only under GH control, but also can be regulated by sexual hormones; this hormonal modulation is related to reproductive phase.


Subject(s)
Insulin-Like Growth Factor Binding Protein 2/physiology , Ovary/physiology , Receptor, IGF Type 1/physiology , Sea Bream/physiology , Somatomedins/physiology , Animals , Female , Insulin-Like Growth Factor Binding Protein 2/biosynthesis , Insulin-Like Growth Factor Binding Protein 2/genetics , Insulin-Like Growth Factor I/biosynthesis , Insulin-Like Growth Factor I/genetics , Insulin-Like Growth Factor I/physiology , Insulin-Like Growth Factor II/biosynthesis , Insulin-Like Growth Factor II/genetics , Insulin-Like Growth Factor II/physiology , Ovary/metabolism , Receptor, IGF Type 1/biosynthesis , Receptor, IGF Type 1/genetics , Sea Bream/genetics , Sea Bream/metabolism , Somatomedins/biosynthesis , Somatomedins/genetics
10.
J Exp Clin Cancer Res ; 24(4): 541-6, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16471316

ABSTRACT

In the present study, we report results of 28 rectal cancer patients, aged 70 years and older, treated with preoperative radiotherapy and 5FU concomitant chemotherapy. Twenty-eight out of 136 patients treated in our Department between 1997 and 2004 aged > or = 70 years, mean 73 (range 70-81); 3 T2, 18 T3, 7 T4; 15 N0, 5N1, 8 N2; Radiotherapy (5040 cGy, 28 fractions) was delivered combined with 5FU - based concomitant chemotherapy. Compliance to chemoradiotherapy was excellent. Major acute toxicity (> or = G3) evaluation showed haematological Grade 3 only in 2 patients. No severe acute Gastrointestinal toxicity was observed. All patients underwent surgery without severe perioperative complications. Complete pathological response pT0 was found in 3 patients (11%). Overall T downstaging occurred in 61% of the cases. Mean follow up was 34 months (range 4- 84). Kaplan Meier Overall Survival and Disease Free Survival at 5 years were 74% (95% CI 54 -95) and 65% (95% CI 38-93), respectively. Only 1 patient showed G3 diarrhea according to CTCAE that interfered with his Quality of Life and required hospitalization. In conclusion, concomitant radiochemotherapy 5FU based is safe in rectal cancer patients aged > or = 70 with a good tumour downstaging (61% of patients) and excellent feasibility. No treatment related death was observed.


Subject(s)
Colorectal Neoplasms/mortality , Colorectal Neoplasms/radiotherapy , Colorectal Neoplasms/surgery , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Chemotherapy, Adjuvant , Combined Modality Therapy , Disease-Free Survival , Humans , Neoadjuvant Therapy , Radiotherapy, Adjuvant , Survival Analysis
11.
Biol Reprod ; 70(3): 737-43, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14613903

ABSTRACT

The vasa gene is an important maternal regulator of primordial germ cell (PGC) development in both vertebrate and invertebrate models. It is also expressed in the mature gonads, but its role in these tissues is still unclear. In oviparous species, oogenesis is a complex process under hormonal control: estrogens, gonadotropins, and other hormones operate at different stages of oogenesis, regulating meiosis, vitellogenesis, follicle maturation, and egg release. The aim of this work is the determination of a regulative role of hormones controlling oocyte maturation on vasa mRNA expression in the sea bream ovary through a molecular biology approach. By in situ hybridization and reverse transcription-polymerase chain reaction (RT-PCR), reaction (the vasa mRNA in the sea bream ovary was found to be expressed at higher levels in the advanced stages of oocyte maturation. After in vivo hormonal treatment, the effect on ovarian vasa mRNA expression was studied through semiquantitative RT-PCR. The quantification of vasa-like mRNA expression in sea bream ovary demonstrates that estradiol (E2), growth hormone (GH), and the combination of gonadotropin-releasing hormone (GnRH) with GH are able to induce an increase in vasa mRNA expression. In contrast, the treatments with GnRH alone or E2 plus GH significantly decreased vasa mRNA expression. These data suggest a regulative interplay between the vasa gene expression and the endocrine system that controls the oogenesis in the ovary of the sea bream.


Subject(s)
Ovary/physiology , RNA Helicases/genetics , Sea Bream/genetics , Amino Acid Sequence , Animals , Base Sequence , Blotting, Northern , Cloning, Molecular , DNA, Complementary , Female , In Situ Hybridization , Molecular Sequence Data , Oocytes/physiology , Oogenesis/physiology , RNA, Messenger/analysis
12.
Mol Reprod Dev ; 66(3): 291-6, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14502608

ABSTRACT

In the present study, the sea-bream Sparus aurata, a pelagic egg spawner, was used as experimental model, in order to establish the occurrence of apoptosis in vertebrates with external reproduction. The same female ovulates floating and nonfloating eggs, but only the former, after fertilization, proceed to embryo development. The eggs were divided into floating and nonfloating and both were analyzed for the presence of several apoptosis markers. The results here reported provide evidence that the nonfloating cells present severe shrinkage and highly express both FAS receptor and FAS ligand on their surface. Furthermore, DNA fragmentation and mitochondria swelling were found, suggesting that the nonfloating eggs were cells programmed to die.


Subject(s)
Apoptosis/physiology , Oocytes/physiology , Ovarian Follicle/metabolism , Ovum/physiology , Sea Bream/physiology , Animals , DNA Fragmentation , Fas Ligand Protein , Female , Membrane Glycoproteins/metabolism , Mitochondria/pathology , Ovarian Follicle/cytology , Ovum/ultrastructure , Proteins/metabolism , Sea Bream/anatomy & histology , fas Receptor/metabolism
13.
Mol Reprod Dev ; 58(3): 330-5, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11170274

ABSTRACT

In pelagic egg spawners, the production of large numbers of sinking eggs, unable to develop into embryos, represents one of the major limiting factors in controlled reproduction. The aim of this study is to elucidate the molecular differences between floating and nonfloating eggs at cytoplasmic and nuclear level. Comparison of analyses between floating and nonfloating sea bream Sparus aurata eggs evidenced differences in vitelline envelope protein components, such differences being probably related with the hydration process but not with fertilization as supported by the assessment of DNA that doubled after in vitro insemination. These data clearly indicated that the absence of embryo development in nonfloating eggs is not due to lack of fertilization. The cytoplasmic composition was also different, the number of protein components being higher in floating eggs, and these extra components may generate the appropriate osmotic pressure at the base of the hydration process. Some lysosomal enzymes, such as cathepsin D and L both involved in yolk proteolysis, in virgin nonfloating eggs were significantly higher with respect to floating ones; the levels of these two enzymes significantly increased in the latter after fertilization. On the contrary, in nonfloating eggs cathepsin L significantly decreased after fertilization. These changes may be related with a series of metabolic processes vital for the production of viable offspring. The capacity of egg transcription and the protein synthesis in these two types of eggs, indicated by the RNA/DNA and RNA/protein ratios, evidenced that the status of cell transcription rate and protein synthesis capacity is significantly higher in floating eggs. This, in turn, suggested that the lack of embryo development may be due to low levels of proteins involved in cell cycle regulation.


Subject(s)
Egg Proteins/analysis , Ovum/chemistry , Ovum/physiology , Sea Bream/physiology , Animals , Blotting, Western , DNA/analysis , Electrophoresis, Polyacrylamide Gel , Female , Fertilization , RNA/analysis
14.
Mol Cell Endocrinol ; 167(1-2): 33-41, 2000 Sep 25.
Article in English | MEDLINE | ID: mdl-11000518

ABSTRACT

A partial cDNA encoding for the C-terminus of vitellogenin (VTG) was cloned from liver of Sparus aurata male treated with 17beta-estradiol (E(2)). E(2) treatment of S. aurata males resulted in increased synthesis and secretion of VTG protein into the plasma, determined by a specific enzyme-linked immunosorbent assay (ELISA) in a time-dependent manner. While VTG mRNA was induced by E(2) treatment, transthyretin (TTR) mRNA levels were reduced. These data provide the first demonstration that estrogen exhibits contrasting effect on VTG and on TTR gene expression in teleosts.


Subject(s)
Estradiol/pharmacology , Prealbumin/metabolism , Sea Bream/metabolism , Vitellogenins/metabolism , Amino Acid Sequence , Animals , Blotting, Northern , Blotting, Western , Cloning, Molecular , Enzyme-Linked Immunosorbent Assay , Female , Gene Expression Regulation/drug effects , Liver/chemistry , Male , Molecular Sequence Data , Prealbumin/genetics , RNA, Messenger/metabolism , Sea Bream/genetics , Sequence Alignment , Vitellogenins/blood , Vitellogenins/genetics
15.
Environ Manage ; 25(3): 247-263, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10629308

ABSTRACT

/ The preparation of landslide maps is an important step in any landslide hazard assessment. Landslides maps are prepared around the world, but little effort is made to assess their reliability, outline their main characteristics, and pinpoint their limitations. In order to redress this imbalance, the results of a long-term research project in the Upper Tiber River basin in central Italy are used to compare reconnaissance and detailed landslide inventory maps, statistical and geomorphologically based density maps, and landslide hazard maps obtained by multivariate statistical modeling. An attempt is made to discuss advantages and limitations of the available maps, outlining possible applications for decision-makers, land developers, and environmental and civil defence agencies. The Tiber experiment has confirmed that landslides can be cost-effectively mapped by interpreting aerial photographs coupled with field surveys and that errors and uncertainties associated with the inventory can be quantified. The experiment has shown that GIS makes it easy to prepare landslide density maps and facilitates the production of statistically based landslide hazard models. The former supply an overview of the distribution of landslides that is easily comprehended but do not provide insight on the causes of instability. The latter, giving insight into the causes of instability, are diagnostically powerful, but are difficult to prepare and exploit.

16.
Article in English | MEDLINE | ID: mdl-10503863

ABSTRACT

OBJECTIVE: Recent epidemiologic studies have identified a trend of increasing cancer incidence in younger patients. The purpose of this study was to determine whether this might be reflected by different molecular mechanisms for tumor development. STUDY DESIGN: Dysplastic and malignant oral lesions from age-distinct patient populations were immunohistochemically analyzed for expression of p53 and cyclin D1. Chi-square analysis was used to determine statistical significance. RESULTS: Eighty-two percent of "older" and 75% of "younger" carcinomas stained positively with p53; 63% of carcinomas in the older population and 55% of carcinomas in the younger population showed cyclin D1 positivity. Dysplasias showed similar cyclin D1 staining in both groups. Interestingly, 100% of "younger" dysplasias stained positively for p53, whereas 35.3% of "older" dysplastic lesions showed immunoreactivity. Staining of carcinomas was not statistically significant, whereas p53 staining of dysplasias proved highly significant (P < .025). CONCLUSIONS: p53 immunoreactivity is detectable at an earlier stage of carcinogenesis in younger patients than in the traditional risk population for oral cancer.


Subject(s)
Carcinoma, Squamous Cell/chemistry , Cyclin D1/metabolism , Mouth Neoplasms/chemistry , Tumor Suppressor Protein p53/metabolism , Adult , Age Factors , Aged , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/immunology , Chi-Square Distribution , Cyclin D1/analysis , Female , Humans , Immunoenzyme Techniques , Male , Middle Aged , Mouth Neoplasms/genetics , Mouth Neoplasms/immunology , Neoplasm Proteins/analysis , Precancerous Conditions/chemistry , Precancerous Conditions/genetics , Precancerous Conditions/immunology , Tumor Suppressor Protein p53/analysis
17.
Oral Oncol ; 34(3): 211-8, 1998 May.
Article in English | MEDLINE | ID: mdl-9692056

ABSTRACT

The excessive proliferation exhibited by cancer cells is frequently a result of their failure to adequately regulate cell cycle progression. In the present study, we developed a xenograft model of oral cancer in athymic mice, using squamous carcinoma cell lines and examined the ability of the cyclin-dependent kinase inhibitor p21 (WAF1/Cip1) to retard tumour growth in vivo, using a retroviral delivery system. Human p21 cDNA was cloned by polymerase chain reaction, expressed, and the encoded protein shown to have biological activity in in vitro kinase assays. Amphotropic retrovirus cultures which expressed recombinant p21 were generated and used to treat established squamous cell carcinoma xenografts. Two weeks following onset of treatment tumours injected with p21 virus producer cells showed a reduction in size between 3- and 10-fold compared with tumours which received control cells which produced control virus alone. The data indicate that recombinant p21 may be of future use for therapeutic intervention in oral cancer.


Subject(s)
Carcinoma, Squamous Cell/therapy , Cyclins/physiology , Genetic Therapy/methods , Mouth Neoplasms/therapy , Animals , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Cyclin-Dependent Kinase Inhibitor p21 , Genetic Vectors , Humans , Mice , Mice, Nude , Mouth Neoplasms/metabolism , Mouth Neoplasms/pathology , Neoplasm Transplantation , Retroviridae/genetics , Transplantation, Heterologous , Tumor Cells, Cultured
18.
Melanoma Res ; 8(2): 131-7, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9610865

ABSTRACT

Theophylline- and caffeine-treated B16-F10 cells exhibited low adhesion to laminin/collagen type IV and reduced invasion through Matrigel in an in vitro assay. In contrast, theobromine appeared ineffective. When young adult C57BL/6 mice were injected intravenously with theophylline-treated B16-F10 cells, the number of surface lung tumours was markedly reduced. Densitometric analyses performed on digitalized microscopic images of histological sections of lung were used to estimate the frequency (number of lung foci; NLF) and the size (average area of metastatic foci; AMF) of the resulting tumour foci. These parameters were correlated to the proliferation (AMF) and invasion (NLF) of melanoma cells in vivo. The data showed a similar theophylline-induced decrease in the AMF and NLF values (71%, P < 0.01). Caffeine treatment produced a more pronounced decrease in the AMF (61%, P < 0.01) than in the NLF (25%, P < 0.01). To our knowledge, this is the first demonstration that theophylline and caffeine possess the capacity to inhibit not only cell proliferation, but also the metastatic behaviour of melanoma cancer cells.


Subject(s)
Caffeine/pharmacology , Lung Neoplasms/secondary , Melanoma, Experimental/pathology , Melanoma, Experimental/secondary , Theobromine/pharmacology , Theophylline/pharmacology , Animals , Cell Adhesion/drug effects , Cell Division , Collagen , Laminin , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Lung Neoplasms/prevention & control , Male , Melanins/metabolism , Melanoma, Experimental/metabolism , Melanoma, Experimental/prevention & control , Mice , Mice, Inbred C57BL , Monophenol Monooxygenase/metabolism , Neoplasm Invasiveness , Transglutaminases/metabolism , Tumor Cells, Cultured
20.
Mol Carcinog ; 18(2): 78-88, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9049183

ABSTRACT

Loss of wild-type p53, either through deletion or mutation, has been demonstrated in most squamous cell carcinomas of the head and neck (HNSCC). Whether these mutant molecules contribute to tumor progression purely through loss of wild-type functions or by growth-promoting mechanisms, however, remains unclear. To begin to address these issues, we isolated a series of p53 cDNAs from HNSCC cell lines that contain missense or nonsense point mutations, insertions, or deletions. The ability of each of these molecules to transform NIH/3T3 cells to a malignant phenotype was assessed by stable transfection and expression under the control of a strong heterologous promoter. NIH/3T3 cells transfected with pLTR6p53, which harbors an H179L missense mutation, formed large tumors rapidly (in less than 4 wk) when transplanted to athymic mice, as did cells expressing pLTR13p53, which had undergone a V173F missense mutation and an in-frame deletion of 48 bp between codons 208 and 223. Cells transfected with pLTR17p53, predicted from the nucleotide sequence to encode a severely truncated p53 corresponding to the N-terminal 56 amino acids, also formed tumors. Cells transfected with pLTR15p53, which was predicted to encode a less severely truncated molecule, formed much smaller tumors and at lower frequencies. NIH/3T3 cells transfected with pLTR12p53 (exon 7 splice donor mutant), pLTRwtp53 (wild-type p53), or vector alone failed to form tumors for up to 2 mo after transplantation. pLTR6p53-transfected cells exhibited a highly malignant phenotype with invasion of regional lymph nodes, mediastinal and lung metastases, invasion of the abdominal wall, and dissemination throughout the peritoneal cavity. Histological assessment of the tumors revealed intensely vascularized fibrosarcomas with numerous cellular atypia, including frequent and aberrant mitoses. Tumor explants were recultured, and northern blot analysis of cellular RNA confirmed that the expression of exogenous p53 was maintained in each case. These data indicate that different p53 mutants contribute to tumorigenesis by specific mechanisms. Furthermore, the results obtained by using the pLTR17p53 transfectants imply that some truncated molecules may overcome the effects of wild-type p53 to contribute to malignancy.


Subject(s)
Carcinoma, Squamous Cell/genetics , Gene Expression Regulation, Neoplastic , Genes, p53/genetics , Head and Neck Neoplasms/genetics , Mutation , Neoplasms, Experimental/genetics , Transfection , 3T3 Cells , Animals , Female , Humans , Immunohistochemistry , Mice , Mice, Nude , Neoplasm Transplantation , Neoplasms, Experimental/pathology , Plasmids/genetics , Tumor Cells, Cultured
SELECTION OF CITATIONS
SEARCH DETAIL
...