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1.
Phys Rev E ; 101(6-1): 062416, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32688554

ABSTRACT

Molecular motors are fascinating proteins that use the energy of ATP hydrolysis to drive vesicles and organelles along cytoskeleton filaments toward their final destination within the cell. Several copies of these proteins bind to the cargo and take turns transporting the cargo attaching to and detaching from the track stochastically. Despite the relevance of molecular motors to cell physiology, key aspects of their collective functioning are still unknown. In this work we propose a one-dimensional model for the transport of extensive and smooth organelles driven by molecular motors. We ran numerical simulations to study the behavior of the cargo for different motor configurations, focusing on the transport properties observable in the experiments, e.g., average speed of the organelle and variations in length. We found that active motors drive the cargo using two different mechanisms: Either they locate in front of the cargo and pull the organelle or they situate at the cargo lagging edge and push. Variations in the organelle length is in close relation with the fraction of motors in each configuration, which depends on the resisting load. The results of this model were contrasted with experimental data obtained from the tracking of rodlike mitochondria during active transport in Xenopus laevis melanophores.


Subject(s)
Microtubules/metabolism , Models, Biological , Molecular Motor Proteins/metabolism , Organelles/metabolism , Adenosine Triphosphate/metabolism , Animals , Biomechanical Phenomena , Melanophores/metabolism , Xenopus laevis
2.
Bioelectrochemistry ; 135: 107583, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32544783

ABSTRACT

The dielectric properties of the eye lens were studied for healthy and alloxane-induced diabetic rabbits in the frequency range from 500 Hz to 100 kHz electric field and temperatures from 25 to 50 °C. In the full temperature range, the average relative permittivity and dielectric loss values for a healthy lens are lower than those recorded for diabetic tissue. Dielectric relaxation of polar amino acids on the alpha-crystallin surface with a characteristic frequency of 7 kHz in the range of 25-50 °C for healthy and diabetic samples is accompanied by the activation energy of proton conductivity with an average values of 33 and 39 kJ mol-1, respectively. The permittivity decrement, which characterizes the size of the dielectric dispersion with a central relaxation time of 0.023 ms for a diabetic sample, is more than twice as high as for a healthy sample. Measurements on the rabbit eye lens were carried out at ambient temperature above and below the physiological range, since these conditions provide an appropriate pattern of dielectric behavior for the diagnosis of clinical dysfunction of the human lens.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Lens, Crystalline/metabolism , Alloxan , Animals , Electric Impedance , Rabbits , alpha-Crystallins/metabolism
3.
Int Endod J ; 53(3): 354-365, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31581318

ABSTRACT

AIM: To evaluate the specific role of ICAM-1 in host responses against endodontic infection. METHODS: Apical periodontitis was experimentally induced in the mandibular first molars of ICAM-1 knockout and wild-type (WT) mice by pulp exposure to the oral environment. At 7, 21 and 42 days following pulp infection, the animals were euthanized and the jaws were prepared for analysis under conventional and fluorescence microscopy (histopathologic and morphometric analysis), immunohistochemistry (polymorphonuclear leucocytes), enzyme histochemistry (osteoclasts and cementoclasts) and RT-PCR (IL-1 α, TNF-α, INF-γ, IL-10, RANK, RANKL and OPG). A generalized linear model with GLIMMIX procedure with Satterthwaite approximation method of degrees of freedom, Tukey-Kramer, pseudo-ranking nonparametric, Bonferroni-Holm multiple testing adjustment, analysis of variance (ANOVA) and the Tukey's multiple comparisons tests were used to evaluate the statistical differences between the groups using SAS 9.4 and the GraphPad Prism 5.0 software (α = 0.05). RESULTS: Compared to WT mice, ICAM-1 knockout mice had significantly greater bone resorption (P < 0.05), reduced recruitment of neutrophils to periapical inflammatory tissues (P < 0.05) and an increased number of fibroblasts (P < 0.05) at all experimental periods. The osteoclast number was significantly higher in ICAM-1 KO than that of WT animals at all times (P < 0.05), while there was no significant difference between the groups regarding cementoclasts. At day 21, the level of IL-1α, RANK, RANKL and IL-10 had increased significantly in tissues from ICAM-1 KO versus WT mice (P < 0.05), while no significant difference was observed in TNF-α and OPG levels (P > 0.05). Tissue levels of INF-γ were significantly lower in ICAM-1 KO than those in WT mice (P < 0.05). CONCLUSION: ICAM-1 deficiency impaired the host response against endodontic infection, resulting in increased tissue destruction.


Subject(s)
Intercellular Adhesion Molecule-1 , Periapical Periodontitis , Animals , Mice , Mice, Knockout , Osteoclasts , Tumor Necrosis Factor-alpha
4.
Med Oral Patol Oral Cir Bucal ; 22(3): e392-e397, 2017 May 01.
Article in English | MEDLINE | ID: mdl-28390128

ABSTRACT

BACKGROUND: Zygomatic implants are an alternative treatment in the rehabilitation of atrophic maxilla to promote stability in the stomatognathic system. The aim of this study was to compare the electromyographic (EMG) activity of masseter and temporalis muscles in controls and in individuals with complete implant-supported dentures anchored in the zygomatic bone. MATERIALS AND METHODS: Fifty-four volunteers of both genders (mean age 52.5 years) were selected and distributed into two groups: Individuals with zygomatic implant (ZIG; n=27) and fully dentate patients (CG; n=27). MyoSystem-BR1 was used to assess masseter and temporalis muscles EMG activity in different mandibular movements: protrusion, clenching, maximal voluntary contraction (MVC) with Parafilm M®, right and left laterality and chewing (peanuts and raisins). Data was processed, normalized (MVC) and analyzed using the SPSS 21.0. Student t-test (P ≤ 0.05) was used for group comparison. RESULTS: The results were statistically significant (P ≤ 0.05) for protrusion, clenching, right and left laterality and raisin chewing. For the mandibular posture conditions, the ZIG obtained higher EMG activity patterns when compared to CG. For the masticatory performance during chewing of peanuts and raisins, the ZIG showed higher EMG mean values when compared to CG. CONCLUSIONS: The zygomatic implant promoted an active response of the muscle fibers (hyperactivity) during both mandibular posture and chewing conditions, probably due to the absence of periodontal receptors, which play a significant role for preparing a bolus for swallowing.


Subject(s)
Dental Prosthesis, Implant-Supported , Electromyography , Masseter Muscle/physiology , Temporal Muscle/physiology , Zygoma/surgery , Adult , Aged , Female , Humans , Male , Middle Aged
5.
J Gerontol A Biol Sci Med Sci ; 70(2): 163-73, 2015 Feb.
Article in English | MEDLINE | ID: mdl-24550352

ABSTRACT

Aging is usually accompanied by a significant reduction in muscle mass and force. To determine the relative contribution of inactivity and aging per se to this decay, we compared muscle function and structure in (a) male participants belonging to a group of well-trained seniors (average of 70 years) who exercised regularly in their previous 30 years and (b) age-matched healthy sedentary seniors with (c) active young men (average of 27 years). The results collected show that relative to their sedentary cohorts, muscle from senior sportsmen have: (a) greater maximal isometric force and function, (b) better preserved fiber morphology and ultrastructure of intracellular organelles involved in Ca(2+) handling and ATP production, (c) preserved muscle fibers size resulting from fiber rescue by reinnervation, and (d) lowered expression of genes related to autophagy and reactive oxygen species detoxification. All together, our results indicate that: (a) skeletal muscle of senior sportsmen is actually more similar to that of adults than to that of age-matched sedentaries and (b) signaling pathways controlling muscle mass and metabolism are differently modulated in senior sportsmen to guarantee maintenance of skeletal muscle structure, function, bioenergetic characteristics, and phenotype. Thus, regular physical activity is a good strategy to attenuate age-related general decay of muscle structure and function (ClinicalTrials.gov: NCT01679977).


Subject(s)
Aging/physiology , Exercise/physiology , Muscle Fibers, Skeletal/ultrastructure , Muscle, Skeletal/physiology , Adult , Aged , Biopsy, Needle , Calcium/metabolism , Exercise Test , Humans , Insulin-Like Growth Factor I/genetics , Isometric Contraction/physiology , Male , Membrane Proteins/metabolism , MicroRNAs/genetics , Microscopy, Electron, Transmission , Mitochondria, Muscle/metabolism , Muscle Fibers, Skeletal/metabolism , Muscle, Skeletal/metabolism , Muscular Atrophy/pathology , NF-E2-Related Factor 2/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Protein Isoforms/genetics , Proto-Oncogene Proteins/metabolism , RNA, Messenger/metabolism , RNA-Binding Proteins/metabolism , Sedentary Behavior , Sterol Regulatory Element Binding Protein 1/metabolism , Transcription Factors/metabolism , Up-Regulation/physiology , YY1 Transcription Factor/metabolism , Young Adult
6.
J Drug Deliv ; 2013: 147325, 2013.
Article in English | MEDLINE | ID: mdl-23401780

ABSTRACT

Neoplastic dissemination to the leptomeninges is an increasingly common occurrence in patients with both haematological and solid tumors arising outside the central nervous system. Both refinement of diagnostic techniques (Magnetic resonance imaging) and increased survival in patients treated with targeted therapies for systemic tumors account for this increased frequency. Cerebrospinal fluid cytological analysis and MRI confirm clinical diagnosis based on multifocal central nervous system signs/symptoms in a patient with known malignancy. Overall survival in patients with leptomeningeal neoplastic dissemination from solid tumors is short, rarely exceeding 3-4 months. However, selected patients may benefit from aggressive therapies, Apart from symptomatic treatment, intrathecal chemotherapy is used, with both free (methotrexate, Thiotepa, AraC) and liposomal antitumor agents (liposomal AraC). Palliative radiotherapy is indicated only in cases of symptomatic bulky disease, surgery is limited to positioning of Ommaya recervoirs or C5F shunting. We report clinical data on a cohort of 26 prospectively followed patients with neoplastic leptomeningitis followed in Lombardia, Italy, in 2011. Prognostic factors and pattern of care are reported.

7.
Dentomaxillofac Radiol ; 36(4): 211-7, 2007 May.
Article in English | MEDLINE | ID: mdl-17536088

ABSTRACT

OBJECTIVES: To evaluate the accuracy and reliability of conventional (Kodak Ektaspeed Plus film) and digitized radiographic images to detect the presence as well to estimate the size, as measured by an image analysis programme, of periapical radiolucencies induced in dog teeth in comparison with the histomorphometric data obtained from the same lesions by conventional and fluorescence microscopy. METHOD: After the removal of pulp, the root canals of five premolars from the same animal were left exposed for 7 days after which they were sealed for 60 days. At day 53, three more premolars were opened and left exposed to the oral cavity for 7 days. Intact premolars were used as control. Conventional radiographs were taken at day 0, day 7, day 30, day 45 and day 60. Morphometry in digitized radiographic images and histological sections were compared at day 7 and day 60 after setting the experimental series. RESULTS: Radiographically, periapical lesions were only detected 30 days after coronal sealing. A progressively increasing radiolucent lesion area was observed at day 45 and day 60. Histopathologically, 7 days after pulp removal dense inflammatory infiltrate and root resorption in the periapical region was observed. At day 7 and day 60, the lesion sizes were similar when evaluated by both conventional and fluorescence microscopy. Lesion size was about 20% larger in digitized radiographs in comparison with histological measurements. CONCLUSIONS: Although image digitization could not improve the detection of the early stages of periapical lesions, it provides a valuable quantitative assessment of extensive periapical lesions. In addition, fluorescence light microscopy enhances the visualization of the apical and periapical structures and seems to be a highly useful tool for histological evaluation, valuable for both qualitative and quantitative studies of periapical disease.


Subject(s)
Periapical Periodontitis/diagnostic imaging , Periapical Periodontitis/pathology , Radiography, Dental/methods , Animals , Dogs , Microscopy, Fluorescence , Radiography, Dental, Digital , Root Resorption/diagnostic imaging , Statistics, Nonparametric , X-Ray Film
8.
G Ital Med Lav Ergon ; 28(2): 209-10, 2006.
Article in Italian | MEDLINE | ID: mdl-16805470

ABSTRACT

Exposure to respirable cristalline silica dust during construction activities can cause silicosis and, in accordance with International Agency for Research on Cancer (IARC), even lung cancer. Among the different facets of construction, residential buildings are of particular interest because the lack of exposure data for workers employed. In this sector a dry sand-blasting of brick ceiling and renewal activities has been investigated. The survey has been carried out in a civil dwelling and 58 samples have been collected using the SKC aluminium cyclone and Door-Oliver plastic cyclone at flow-rate 2.2-1.7 l/min. The respirable dust samples were analysed by x-ray diffraction using NIOSH Method 7500. Even if the results of this study should be considered preliminary, they showed SLC respirable concentrations even many time above TLV-TWA during a sand-blasting activities and some times also during the other activities. Awaiting the correct classification from European Community, it would be desiderable that the workers would had appropriate information and prevention on the specific risks associated to the dust in the construction activities.


Subject(s)
Air Pollution, Indoor/analysis , Industry , Occupational Exposure/analysis , Silicon Dioxide/analysis , Humans
9.
Int Immunol ; 12(9): 1329-35, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10967028

ABSTRACT

The idiopathic inflammatory myopathies are characterized by antibody- or cell-mediated immune response against unknown muscle tissue antigens. In these diseases a cellular infiltrate, composed of T and B lymphocytes, macrophages and NK cells, may invade muscle tissue with a gradient from the perivascular space to the endomysial compartment. Muscle cells may be actively involved in the processes of mononuclear cell recruitment and activation from the blood stream to the areas of inflammation. In order to verify this hypothesis, cultured human myoblasts were tested for their capacity to express different pro-inflammatory cytokines [IL-1alpha, IL-1beta, IL-6 and tumor necrosis factor (TNF)-alpha] and chemokines (IL-8, MCP-1 and RANTES) at the mRNA level and protein secretion, in the presence of the pro-inflammatory cytokines IFN-gamma and TNF-alpha alone or in combination. We confirmed that human myoblasts expressed IL-1alpha and IL-6 constitutively, while IL-1beta and TNF-alpha are detected only after treatment with pro-inflammatory cytokines; moreover, we observed that TNF-alpha was expressed on an autocrine fashion by myoblasts. IL-8 and RANTES were expressed constitutively while MCP-1 after proper induction. These molecular data were further confirmed by specific ELISA in the supernatant from cultured myoblasts. Our results underline the importance of human myoblasts in the recruitment of leukocytes from the blood stream and, most probably, in the cross-talk between infiltrating inflammatory cells and muscle cells, creating the conditions for a chronic inflammation. Moreover, the capacity of muscle cells to behave as cells of the immune system has to be kept in mind, also in view of i.m. vaccination and use of molecular engineered myoblasts as vehicles in gene therapy.


Subject(s)
Chemokines/biosynthesis , Cytokines/biosynthesis , Muscle, Skeletal/immunology , Cells, Cultured , Chemokine CCL2/analysis , Chemokine CCL2/genetics , Chemokine CCL2/metabolism , Chemokine CCL5/analysis , Chemokine CCL5/genetics , Chemokine CCL5/metabolism , Chemokines/genetics , Cytokines/genetics , Enzyme-Linked Immunosorbent Assay , Gene Expression Profiling , Humans , Interferon-gamma/pharmacology , Interleukin-1/analysis , Interleukin-1/genetics , Interleukin-1/metabolism , Interleukin-6/analysis , Interleukin-6/genetics , Interleukin-6/metabolism , Interleukin-8/analysis , Interleukin-8/genetics , Interleukin-8/metabolism , Muscle, Skeletal/drug effects , Myositis/immunology , RNA/genetics , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction , Tumor Necrosis Factor-alpha/pharmacology
10.
Eur J Neurosci ; 10(9): 2768-75, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9758147

ABSTRACT

Advanced glycation end-products (AGEs) are irreversible compounds which, by abnormally accumulating over proteins as a consequence of diabetic hyperglycaemia, can damage tissues and thus contribute to the pathogenesis of diabetic complications. This study was performed to evaluate whether restoration of euglycaemia by islet transplantation modifies AGE accumulation in central and peripheral nervous tissue proteins and, as a comparison, in proteins from a non-nervous tissue. Two groups of streptozotocin diabetic inbred Lewis rats with 4 (T1) or 8 (T2) months disease duration were grafted into the liver via the portal vein with 1200-1500 islets freshly isolated from normal Lewis rats. Transplanted rats, age-matched control and diabetic rats studied in parallel, were followed for a further 4-month period. At study conclusion, glycaemia, glycated haemoglobin and body weight were measured in all animals, and an oral glucose tolerance test (OGTT) performed in transplanted rats. AGE levels in cerebral cortex, spinal cord, sciatic nerve proteins and tail tendon collagen were measured by enzyme-linked immunosorbent assay (ELISA). Transplanted animal OGTTs were within normal limits, as were glycaemia and glycated haemoglobin. Diabetic animal AGEs were significantly higher than those of control animals. Protein AGE values were reduced in many transplanted animals compared to diabetic animals, reaching statistical significance in spinal cord (P < 0.05), sciatic nerve (P < 0.02) and tail tendon collagen (P < 0.05) of T1 animals. Thus, return to euglycaemia following islet transplantation after 4 months of diabetes with poor metabolic control reduces AGE accumulation rate in the protein fractions of the mixed and purely peripheral nervous tissues (spinal cord and sciatic nerve, respectively). However, after a double duration of bad metabolic control, a statistically significant AGE reduction has not been achieved in any of the tissues, suggesting the importance of an early therapeutic intervention to prevent the possibly pathological accumulation of AGEs in nervous and other proteins.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Glycation End Products, Advanced/metabolism , Islets of Langerhans Transplantation , Nerve Tissue Proteins/metabolism , Animals , Blood Glucose/analysis , Body Weight , Enzyme-Linked Immunosorbent Assay , Glycated Hemoglobin/analysis , Glycation End Products, Advanced/analysis , Male , Nerve Tissue Proteins/chemistry , Organ Size , Rats , Rats, Inbred Lew , Solubility , Tail , Tendons/chemistry
11.
Stud Health Technol Inform ; 52 Pt 1: 237-41, 1998.
Article in English | MEDLINE | ID: mdl-10384454

ABSTRACT

In this paper we will describe the SeCD (Service for the Care of Drug addicts) electronic folder, a specific application of CADMIO [1] (Computer Aided Design for Medical Information Objects) system. CADMIO is a system for the definition, construction and management of multimedia clinical folders. The Ser.T. (Servizio per la Tossicodipendenza/Service for Drug Addicts) has earned a very special place within the Italian clinical structures as well as any service for drug addicts has done in the rest of the world. Such a structure has special needs and the characteristics of its medical folders are very different from any other folder. Actually, a Ser.T. has to keep updated the patient situation either from the clinical point of view as well as the psychiatric one. Moreover, it must keep track of the clinician subjective considerations about the patient psychic state and his situation in regard of the law. So, we had to redesign some of the features of the existing CADMIO application, to accommodate such highly not structured data into objects easily manipulated by an informative system. The objectives we hope to achieve were mainly two: To show that a well designed adaptive system can be easily exploited to support even very complex and poorly structured data types and actions To design data structures able to accommodate medical, psychiatric and administrative data in an homogeneous manner.


Subject(s)
Database Management Systems , Medical Records Systems, Computerized/organization & administration , Multimedia , Substance-Related Disorders/therapy , Computer Systems , Humans , Hypermedia , Information Systems/organization & administration , Psychiatry , Substance-Related Disorders/psychology , User-Computer Interface
12.
J Natl Cancer Inst ; 88(7): 442-9, 1996 Apr 03.
Article in English | MEDLINE | ID: mdl-8618236

ABSTRACT

UNLABELLED: BACK: The functional organization of polarized epithelia depends mostly on adhesion molecules belonging to the integrin and cadherin families. These molecules either recognize basement membrane components, such as laminins, or form intercellular junctions via homotypic interactions. Such tissue organization is often disrupted upon neoplastic transformation, and the resulting loss of functional polarization and cell cohesion might be a prerequisite for the invasive and metastatic behavior of carcinomas. PURPOSE: We studied modifications on thyroid adhesive mechanisms at various stages of neoplastic progression in terms of adhesion molecule expression, topography, and functional regulation by tyrosine kinases. Starting from this working hypothesis, we sought to identify one or more biological markers that would be suggestive of malignant transformation and poorer prognosis and that could be developed as a reliable indicator(s) in early diagnostic steps. METHODS: The study was carried out on both surgical samples and the corresponding fine-needle aspiration biopsy smears (numbers of specimens collected: 19 adenomas, seven follicular carcinomas, 13 papilary carcinomas, and 39 normal tissues). Immunohistochemistry of tissue sections and smears and immuno-precipitation and western blot analysis of protein extracts were done with a battery of monoclonal and polyclonal antibodies. Northern blotting was performed on RNA extracts from frozen tissue samples and use of an integrin subunit beta4 complementary DNA probe. RESULTS: Our findings can be summarized as follows: 1) In normal thyroid cells, the cooperative role of integrin alpha6beta4 and laminin 5/kalinin in hemidesmosome-mediated adhesion adhesion is missing, and recognition of the basal lamina occurs via integrin alpha3beta1 and laminin 1 and/or 2 (this pattern being maintained in adenomas but altered in carcinomas regardless of their histotype or differentiation grade); 2) only in carcinomas with clinical and/or histologic aggressiveness do neoexpression of integrin subunit beta4 and loss of laminin 2/merosin occur, indicating de novo assembly of integrin alpha6beta4; 3) pericellular redistribution and cytoskeletal disconnection of the E-cadherin-catenin complex occur; and 4) basal E-cadherin tyrosine phosphorylation decreases in carcinomas as compared with that in normal and adenomatous tissue. CONCLUSION: The malignant progression of thyroid tumors involves marked rearrangement of cell-basement membrane and cell-cell adhesion molecules and changes in their cytoskeleton linkage. These rearrangements are also easily and reproducibly detected on fine-needle aspiration biopsy smears. IMPLICATIONS: Immunodetection of adhesion molecules in sections and/or fine-needle smears may complement the toolbox of thyroid surgical pathologists; it may expand the possibilities of achieving a correct early diagnosis of thyroid tumors and of gaining some prognostic information on thyroid tumors.


Subject(s)
Cadherins/biosynthesis , Integrins/biosynthesis , Thyroid Gland/metabolism , Thyroid Neoplasms/metabolism , Adenocarcinoma, Follicular/metabolism , Adenocarcinoma, Follicular/pathology , Adenocarcinoma, Follicular/surgery , Adenoma/metabolism , Adenoma/pathology , Adenoma/surgery , Adult , Aged , Antibodies, Monoclonal , Biopsy, Needle , Blotting, Western , Cadherins/analysis , Carcinoma, Papillary/metabolism , Carcinoma, Papillary/pathology , Carcinoma, Papillary/surgery , Disease Progression , Female , Fluorescent Antibody Technique, Indirect , Humans , Immunoenzyme Techniques , Integrins/analysis , Male , Middle Aged , Neoplasm Staging , Protein-Tyrosine Kinases/metabolism , Reference Values , Thyroid Gland/cytology , Thyroid Gland/pathology , Thyroid Neoplasms/pathology , Thyroid Neoplasms/surgery
13.
J Autoimmun ; 9(1): 113-7, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8845049

ABSTRACT

Antineutrophil cytoplasmic antibodies (ANCA) are present in systemic vasculitis with or without renal involvement and in inflammatory bowel diseases, conditions which share damage in proteoglycan content of basal membrane. In diabetes, there is a reduction in proteoglycans in the kidney basal membrane, responsible for the decrease in fixed anionic charges and, consequently, for the prevalent anionic proteinuria (albumin, IgG4) even in the early preclinical stage of nephropathy. The aims of this study were to search for the presence of ANCA in long-standing type 1 diabetic patients and to evaluate possible correlations with size- and/or charge-selective proteinuria. Twenty-two type 1 diabetic patients (duration of diabetes 24 years, range 9-30) selected and grouped according to albumin excretion rate values, were studied together with 21 age and sex comparable normal subjects. ANCA, albumin excretion rate, and the clearances of albumin, of prevalently cationic total IgG (IgG) and of anionic IgG4 were evaluated. ANCA were measured using ELISA and indirect immunofluorescence methods; albumin, IgG and IgG4 were tested with RIA or ELISA methods developed in our laboratory. ANCA were found in five patients, three of whom showed proteinuria. 33.3% and 18.2% of patients with normal IgG and albumin clearances respectively had elevated IgG4 clearance. This study shows for the first time the presence of ANCA in long-standing type 1 diabetic patients and confirms a prevalent anionic protein excretion in these patients, but does not show a correlation between the presence of ANCA and proteinuria, even if the presence of ANCA in diseases sharing alterations in proteoglycan content of vascular basal membrane is noteworthy.


Subject(s)
Diabetes Mellitus, Type 1/immunology , Neutrophils/chemistry , Proteinuria/complications , Adult , Cytoplasm/immunology , Female , Fluorescent Antibody Technique, Indirect , Humans , Immunoglobulin G/analysis , Male , Metabolic Clearance Rate , Middle Aged , Neutrophils/immunology , Serum Albumin/analysis
14.
Diabetes Res Clin Pract ; 28(1): 9-17, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7587917

ABSTRACT

To evaluate accumulation of advanced glycation end-products (AGE) in diabetes and its possible correlation with late diabetic complications, AGE levels were measured by spectrofluorimetry in eye lens and sciatic nerve proteins and isolated tail tendon collagen of rats with experimental diabetes of 3- and 6-month duration. The values obtained were compared to those from age-matched control rats and correlated with cataract presence and somatosensory evoked potential (SEP) alterations. Diabetic animals had increased AGE levels in all tissues at both times; cataract developed in 29% of diabetic rats at 3 months and in 57% at 6 months; SEP conduction velocity was reduced in diabetic animals both at 3 (54.5 +/- 1.8 S.E.M. m/s vs. 73.9 +/- 1.0, P < 0.0001) and 6 months (59.5 +/- 1.4 vs. 71.5 +/- 1.6, P < 0.0001) from diabetes induction. No eye lens AGE level differences were observed when cataract presence was considered. Interestingly, in diabetic rats, increased sciatic nerve AGE levels were associated with reduced SEP. These data show that: (1) AGE levels are increased as early as 3 months from development of hyperglycemia; (2) other factors, in addition to an enhanced rate of fluorescent AGE formation, might play important roles in the pathogenesis of diabetic cataract; (3) increased peripheral nerve AGE levels are associated with SEP alterations.


Subject(s)
Cataract/physiopathology , Diabetes Mellitus, Experimental/physiopathology , Diabetic Retinopathy/physiopathology , Glycation End Products, Advanced/metabolism , Animals , Blood Glucose/metabolism , Collagen/chemistry , Collagen/metabolism , Crystallins/chemistry , Crystallins/metabolism , Diabetes Mellitus, Experimental/complications , Glycation End Products, Advanced/analysis , Lens, Crystalline/metabolism , Male , Nerve Tissue Proteins/chemistry , Nerve Tissue Proteins/metabolism , Rats , Rats, Sprague-Dawley , Reference Values , Sciatic Nerve/metabolism , Spectrometry, Fluorescence , Tendons/metabolism
15.
Biochem Med Metab Biol ; 53(2): 92-7, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7710774

ABSTRACT

An impairment of protein charge selectivity has been invoked to explain the initial anionic proteinuria in diabetic nephropathy. The aims of this work were to investigate charge and size protein perm-selectivity abnormalities in experimental diabetes and to monitor these changes over time after diabetes induction. Diabetes was induced in 56 Sprague-Dawley male rats by streptozotocin; the control group was represented by 38 normal rats. Blood glucose, body weight, urine volumes, and proteinuria in 24-h urine collections were evaluated at 3, 6, 9, and 12 months of diabetes. The Bradford method and mono- and bidimensional gel electrophoresis were used to determine and characterize proteinuria. Body weight increase was lower (P < 0.05, P < 0.0001, P < 0.05 at 3, 6, and 12 months, respectively), urine volumes were greater (P < 0.001, P < 0.005, P < 0.05 at 6, 9, and 12 months, respectively) and the proteinuria was significantly increased (P < 0.05 at 3 months, P < 0.001 at 6 months, P < 0.01 at 9 months, and P < 0.05 at 12 months) in diabetic rats compared with the control group. When the charge and the size of urine proteins were considered, small (30 kDa) and anionic proteins were found to be mainly excreted in diabetic rats, at 3 months of the disease; at 6 months, higher amounts of albumin and cationic proteins with higher molecular weight (50 kDa) were also found in the urine; at 9 and 12 months the changes previously described were associated with an excretion of proteins weighing about 75 kDa.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Diabetes Mellitus, Experimental/complications , Proteinuria/physiopathology , Albuminuria/urine , Animals , Blood Glucose/analysis , Body Weight , Diabetic Nephropathies/urine , Kidney/chemistry , Male , Proteins/chemistry , Proteinuria/complications , Rats , Rats, Sprague-Dawley
16.
Proc Natl Acad Sci U S A ; 91(15): 7291-5, 1994 Jul 19.
Article in English | MEDLINE | ID: mdl-8041783

ABSTRACT

A retroviral construct encoding polyoma middle-sized T antigen was used to generate transformed endothelial cell lines from heart (H5V), brain (B9V), and whole-embryo (E10V) of C57BL/6 mice. When injected into syngeneic recipients, H5V and the less studied B9V and E10V cells caused vascular tumors which, depending on the number of cells inoculated, regressed or progressed, leading to death of the host. When H5V cells were injected into immunodeficient mice, tumors were observed with inocula which did not form lesions in immunocompetent recipients and regression did not occur. Treatment with anti-LFA-1, anti-Thy-1.2, and anti-CD8 antibodies abolished rejection; anti-CD4 was a somewhat less effective inhibitor of resistance. Animals with progressive tumors exhibited secondary lesions in various organs with prominent skin involvement in nude mice. Histologically, the tumors had the appearance of a hemangioma, with areas resembling Kaposi sarcoma. Cells lining vascular lacunae had the morphological features of injected H5V cells. The lesions were characterized by prominent neovascularization and mononuclear cell infiltration. Southern blot hybridization analysis revealed that approximately 5% of the cells in the tumor mass were transplanted H5V cells. Thus, the H5V transformed endothelial line causes vascular lesions that are sustained to a large extent by recruitment of host cells and manifests full malignant behavior only in immunocompromised hosts. The hypothesis of a tumor sustained by a minute proportion of transformed cells, which recruit host elements and express full malignant behavior only in immunodeficient hosts, would account for several features of some vascular neoplasms in man.


Subject(s)
Antigens, Polyomavirus Transforming/physiology , Endothelium, Vascular/pathology , Immunocompromised Host , Neoplasms, Vascular Tissue/etiology , Animals , Cell Division , Cell Line, Transformed , Cell Transformation, Neoplastic , Cell Transformation, Viral , Cloning, Molecular , Mice , Mice, Inbred C57BL , Neoplasms, Vascular Tissue/immunology , Neoplasms, Vascular Tissue/pathology
17.
J Exp Med ; 179(2): 739-43, 1994 Feb 01.
Article in English | MEDLINE | ID: mdl-8294881

ABSTRACT

Whereas the signaling function of the interleukin 1 (IL-1) receptor type I (IL-1R I) has been well documented, the type II "receptor" has been suggested to act as a decoy target for this cytokine. Since IL-1 may represent a key target of the immunomodulatory and antiinflammatory properties of glucocorticoids (GC), the aim of this study was to investigate the effects of dexamethasone (Dex) on IL-1R expression in human polymorphonuclear leukocytes (PMN), which express predominantly the type II molecule (IL-1R II). We found that Dex augments the levels of steady state transcripts encoding the IL-1R I and, most prominently, those of IL-1R II. Dex induced both transcripts via transcription-dependent mechanisms and by prolongation of the mRNAs half-lives. Inhibition of protein synthesis superinduced basal and Dex-augmented IL-1R II mRNA, whereas it completely inhibited the induction by Dex of IL-1R I transcripts. Induction of IL-1R II mRNA by Dex was associated with augmented membrane expression and release of the type II IL-1 binding molecule. This effect was mediated by the GC receptor. Other steroids (17 beta-estradiol, progesterone, and testosterone) were ineffective. The concentrations of IL-1 alpha and IL-1 receptor antagonist required to displace the binding of IL-1 beta to the soluble form of the decoy molecule induced by Dex from PMN were, respectively, 100 and 2 times higher compared with IL-1 beta. The induction by Dex of the type II receptor, a decoy molecule for IL-1, may contribute to the immunosuppressive and antiinflammatory activities of Dex.


Subject(s)
Dexamethasone/pharmacology , Interleukin-1/metabolism , Neutrophils/metabolism , Receptors, Interleukin-1/biosynthesis , Half-Life , Humans , In Vitro Techniques , Ligands , Neutrophils/drug effects , RNA, Messenger/metabolism , Receptors, Interleukin-1/antagonists & inhibitors , Receptors, Interleukin-1/metabolism , Solubility
18.
Diabetologia ; 36(9): 797-801, 1993 Sep.
Article in English | MEDLINE | ID: mdl-8405749

ABSTRACT

D-Lysine, the non-physiological isomer of L-lysine, can competitively reduce protein non-enzymatic glycation in vitro. To study the effect of D-lysine in vivo, 6-8-week old Sprague-Dawley rats with streptozotocin-induced diabetes mellitus were treated from diagnosis for 45 days with two daily subcutaneous injections of D-lysine (0.5 g.ml-1.day-1). Another group of diabetic rats was only injected with equal volumes of physiological saline (0.9% NaCl). Glycated haemoglobin was measured by ion exchange chromatography, and glycated serum and lens proteins by boronate affinity gel chromatography. Serum and urinary creatinine concentrations were evaluated by the alkaline-picrate reaction. Urinary lysine concentrations at mid- and end-study were evaluated by cation exchange chromatography. Blood glucose concentrations, serum creatinine levels and creatinine clearances, measured at the end of the study, were similar in both diabetic groups (> 22.0 mmol/l, < or = 106 mumol/l and approximately 0.02 ml/s, respectively). Urinary lysine concentration in D-lysine-treated diabetic animals was more than 50-fold higher than in placebo-treated diabetic rats. In D-lysine-treated vs placebo-treated diabetic animals, a statistically significant reduction was found in the levels of glycated haemoglobin (stable HbA1; mean +/- SD = 3.00 +/- 0.74% vs 4.02 +/- 0.46%, p < 0.05; labile HbA1 = 3.92 +/- 0.89% vs 5.84 +/- 0.61%, p < 0.005), glycated serum proteins (1.40 +/- 0.47% vs 2.52 +/- 1.15%, p < 0.05) and glycated lens proteins (4.90 +/- 0.96% vs 5.98 +/- 0.65%, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Blood Proteins/drug effects , Diabetes Mellitus, Experimental/blood , Glycoproteins , Lysine/pharmacology , Animals , Blood Glucose/metabolism , Blood Proteins/metabolism , Diabetes Mellitus, Experimental/physiopathology , Diabetes Mellitus, Experimental/urine , Glycosylation/drug effects , Lysine/urine , Male , Rats , Rats, Sprague-Dawley , Reference Values , Stereoisomerism , Glycated Serum Proteins
19.
Exp Cell Res ; 206(2): 311-7, 1993 Jun.
Article in English | MEDLINE | ID: mdl-7684696

ABSTRACT

The present study was designed to reexamine the interaction of granulocyte-macrophage colony-stimulating factor (GM-CSF) with endothelial cells (EC) and to investigate the expression of CSF receptor chains in these cells. In agreement with previous data, GM-CSF induced directional migration and, to a lesser degree, proliferation of human umbilical vein EC. When compared to basic fibroblast growth factor, GM-CSF was comparable in terms of chemotactic activity and was substantially less active in terms of proliferation. Binding studies confirmed the presence of receptors for GM-CSF (GM-CSFR) on EC. The expression of the beta chain common to the GM-CSFR, IL-3 receptor, and IL-5 receptor, as well as of the individual alpha chains, was studied by Northern analysis and/or reverse transcription and polymerase chain reaction. EC expressed high levels of the common beta chain transcripts. Expression of the alpha(GM) and alpha(IL-5) chain mRNA was minimal or absent in normal EC, though the transformed ECV304 endothelial cell line had substantial amounts of alpha(GM) chain mRNA. Unexpectedly, EC expressed alpha(IL-3) chain transcripts. IL-3 induced migration of EC across polycarbonate filters, whereas IL-5 was inactive.


Subject(s)
Endothelium, Vascular/physiology , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Receptors, Immunologic/metabolism , Receptors, Interleukin-3/metabolism , Receptors, Interleukin , Animals , Base Sequence , Cell Division/drug effects , Cells, Cultured , Chemotaxis/drug effects , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Humans , Interleukin-3/pharmacology , Interleukin-5/metabolism , Kinetics , Macromolecular Substances , Mice , Molecular Sequence Data , Oligodeoxyribonucleotides , Polymerase Chain Reaction , RNA/genetics , RNA/isolation & purification , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/genetics , Receptors, Immunologic/genetics , Receptors, Interleukin-3/genetics , Receptors, Interleukin-5 , Recombinant Proteins/pharmacology , Transcription, Genetic , Umbilical Veins
20.
Acta Diabetol ; 30(3): 138-42, 1993.
Article in English | MEDLINE | ID: mdl-8111073

ABSTRACT

A possible loss in kidney charge permselectivity of proteins before any manifestation of nephropathy has been sought in type 2 (non-insulin-dependent) diabetes by assessing the clearances of proteins differing in charge and/or size (anionic and cationic immunoglobulins, albumin). Eighty-five consecutive outpatients with type 2 diabetes were studied and compared with 101 normal subjects. Of the patients, 14.1% were microalbuminuric and 2.3% macroalbuminuric. A significant increase in protein clearances was observed in diabetic patients in comparison with normal subjects: the median of albumin clearance was 0.09 ml/min, interquartile range (IR) 0.04-0.31 (P < 0.01 vs normals); that of anionic immunoglobulins (IgG4) 0.02 ml/min, IR 0.04-0.05 (P < 0.005 vs normals); and that of neutral/cationic immunoglobulins (IgG) 0.13 ml/min, IR 0.07-0.19 (P < 0.01 vs normals). The anionic/cationic immunoglobulin ratio median was 0.22, IR 0.11-0.43, and exceeded the upper limit of normal values in 29.4% of all patients. IgG4 clearance was positively correlated with albumin clearance (r = 0.72) and with IgG clearance (r = 0.98). Nevertheless anionic immunoglobulin clearance was increased in a number of patients (17.3%) with normal IgG excretion and even in patients (15.1%) with normal albumin clearance. Clearances of IgG4 and IgG, but not that of albumin, were correlated with the duration of diabetes. Thus, an increased anionic/cationic IgG ratio in type 2 diabetes highlights a charge selectivity defect in protein permselectivity; this selective proteinuria may reflect more accurately than does microalbuminuria an early kidney abnormality in this form of diabetes.


Subject(s)
Albuminuria , Diabetes Mellitus, Type 2/physiopathology , Immunoglobulin G/urine , Proteinuria , Adult , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/urine , Female , Humans , Immunoglobulin G/classification , Male , Middle Aged , Reference Values
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