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1.
Injury ; 49 Suppl 3: S19-S25, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30415664

ABSTRACT

INTRODUCTION: Few clinical studies have analyzed the utility of distal interlocking screws in stable and unstable intertrochanteric fractures treated with intramedullary devices. We performed a prospective analysis comparing short unlocked versus short dynamic and short static distal locked intramedullary nails. MATERIALS AND METHODS: Nine level-II trauma centres were involved in the study. 240 patients over the age of 65 with a stable (AO/OTA 31-A1) or unstable intertrochanteric fracture (AO/OTA 31-A2) were prospectively investigated. The same type of nail was used in every patient. Patients were randomly divided into 3 groups according to the type of distal locking used. Intra-operative variables were examined and patients were followed clinically and radiographically at 1, 3, 6, 12 months postoperatively. All complications were recorded. RESULTS: A total of 212 patients completed 1 year of follow-up visits. In the Unlocking Group (UG) the operation time, blood loss, fluoroscopy time, total length of incision were significantly decreased compared to both the Dynamic Group (DG) and the Static Group (SG) (p < 0.05). Conversely, no reliable differences in intraoperative variables were noted between the Dynamic Group and the Static Group (p > 0.05). In terms of time of fracture union we found no differences among the three Groups (p > 0.05). Moreover, no cases of limb shortening >1 cm or varus collapse were detected in any group. The 3 Groups were similar in terms of HHS, SF-12 and Barthel index results at 1-year follow-up (p > 0.05). Finally, no significant differences were demonstrated across the three Groups in terms of major complications. CONCLUSIONS: This clinical study further confirms the hypothesis that short intramedullary nails do not need to be locked for stable and unstable intertrochanteric fractures.


Subject(s)
Bone Nails , Fracture Fixation, Intramedullary , Fracture Healing/physiology , Hip Fractures/surgery , Joint Instability/surgery , Aged , Female , Fluoroscopy , Follow-Up Studies , Fracture Fixation, Intramedullary/instrumentation , Fracture Fixation, Intramedullary/methods , Hip Fractures/diagnostic imaging , Hip Fractures/physiopathology , Humans , Joint Instability/diagnostic imaging , Joint Instability/physiopathology , Male , Prospective Studies , Range of Motion, Articular , Trauma Centers , Treatment Outcome
2.
J Nanopart Res ; 19(9): 316, 2017.
Article in English | MEDLINE | ID: mdl-28959137

ABSTRACT

Screening nanoparticle toxicity directly on cell culture can be a fast and cheap technique. Nevertheless, to obtain results in accordance with those observed in live animals, the conditions in which cells are cultivated should resemble the one encountered in live systems. Microfluidic devices offer the possibility to satisfy this requirement, in particular with endothelial cell lines, because they are capable to reproduce the flowing media and shear stress experienced by these cell lines in vivo. In this work, we exploit a microfluidic device to observe how human umbilical vein endothelial cells (HUVEC) viability changes when subject to a continuous flow of culture medium, in which spherical citrate-stabilized gold nanoparticles of different sizes and at varying doses are investigated. For comparison, the same experiments are also run in multiwells where the cells do not experience the shear stress induced by the flowing medium. We discuss the results considering the influence of mode of exposure and nanoparticle size (24 and 13 nm). We observed that gold nanoparticles show a lower toxicity under flow conditions with respect to static and the HUVEC viability decreases as the nanoparticle surface area per unit volume increases, regardless of size.

3.
Ann Oncol ; 28(11): 2843-2851, 2017 Nov 01.
Article in English | MEDLINE | ID: mdl-28945835

ABSTRACT

BACKGROUND: This study evaluated whether demographics, pre-diagnosis lifestyle habits and clinical data are associated with the overall survival (OS) and head and neck cancer (HNC)-specific survival in patients with HNC. PATIENTS AND METHODS: We conducted a pooled analysis, including 4759 HNC patients from five studies within the International Head and Neck Cancer Epidemiology (INHANCE) Consortium. Cox proportional hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were estimated including terms reported significantly associated with the survival in the univariate analysis. RESULTS: Five-year OS was 51.4% for all HNC sites combined: 50.3% for oral cavity, 41.1% for oropharynx, 35.0% for hypopharynx and 63.9% for larynx. When we considered HNC-specific survival, 5-year survival rates were 57.4% for all HNC combined: 54.6% for oral cavity, 45.4% for oropharynx, 37.1% for hypopharynx and 72.3% for larynx. Older ages at diagnosis and advanced tumour staging were unfavourable predictors of OS and HNC-specific survival. In laryngeal cancer, low educational level was an unfavourable prognostic factor for OS (HR = 2.54, 95% CI 1.01-6.38, for high school or lower versus college graduate), and status and intensity of alcohol drinking were prognostic factors both of the OS (current drinkers HR = 1.73, 95% CI 1.16-2.58) and HNC-specific survival (current drinkers HR = 2.11, 95% CI 1.22-3.66). In oropharyngeal cancer, smoking status was an independent prognostic factors for OS. Smoking intensity (>20 cigarettes/day HR = 1.41, 95% CI 1.03-1.92) was also an independent prognostic factor for OS in patients with cancer of the oral cavity. CONCLUSIONS: OS and HNC-specific survival differ among HNC sites. Pre-diagnosis cigarette smoking is a prognostic factor of the OS for patients with cancer of the oral cavity and oropharynx, whereas pre-diagnosis alcohol drinking is a prognostic factor of OS and HNC-specific survival for patients with cancer of the larynx. Low educational level is an unfavourable prognostic factor for OS in laryngeal cancer patients.


Subject(s)
Alcohol Drinking/mortality , Head and Neck Neoplasms/mortality , Smoking/mortality , Alcohol Drinking/adverse effects , Female , Follow-Up Studies , Head and Neck Neoplasms/etiology , Humans , International Agencies , Male , Meta-Analysis as Topic , Middle Aged , Prognosis , Risk Factors , Smoking/adverse effects , Survival Rate
4.
Acta Otorhinolaryngol Ital ; 37(6): 458-466, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28663597

ABSTRACT

This study was undertaken to evaluate the association between demographics, lifestyle habits, and clinical data and overall survival (OS), recurrence and second primary cancer (SPC) in patients with first primary head and neck cancer (HNC). We retrospectively reviewed data from 482 patients treated at the "Agostino Gemelli" Teaching Hospital, Rome, between 2002-2012 for primary HNC. Individual parameters were evaluated for association with specific outcomes such as OS, cancer recurrence and second primary cancer (SPC) appearance using hazard ratios (HR) and 95% confidence intervals (CIs). Five-year OS was 60.6% for all HNC cases, 49.0% for oral cavity, 54.8% for oropharynx, 50.0% for hypopharynx and 63.4% for larynx. Predictors of OS were older age (HR = 1.04; 95% CI: 1.02-1.05) and advanced tumour stage (HR = 2.00; 95% CI: 1.41-2.84). The risk of recurrence was associated with drinking 8-14 drinks per week (HR = 1.73; 95% CI: 1.00-2.97). The risk of developing SPC increased with advanced tumour stage (HR = 2.75; 95% CI: 1.39-5.44) and with smoking for more than 40 years (HR = 3.68; 95% CI: 1.10-12.30). OS differed among HNC sites. Increasing age was an unfavourable predictor of HNC OS. Tumour stage was a prognostic factor both for OS and for risk of developing SPC. Alcohol and tobacco consumption were prognostic factors for recurrence and SPC, respectively.


Subject(s)
Head and Neck Neoplasms/mortality , Aged , Female , Head and Neck Neoplasms/therapy , Humans , Italy , Male , Middle Aged , Prognosis , Retrospective Studies , Survival Rate , Time Factors
5.
Eur J Histochem ; 60(2): 2643, 2016 Jun 28.
Article in English | MEDLINE | ID: mdl-27349320

ABSTRACT

Cannabinoid receptors have been localized in the central and peripheral nervous system as well as on cells of the immune system, but recent studies on animal tissue gave evidence for the presence of cannabinoid receptors in different types of tissues. Their presence was supposed also in myofascial tissue, suggesting that the endocannabinoid system may help resolve myofascial trigger points and relieve symptoms of fibromyalgia. However, until now the expression of CB1 (cannabinoid receptor 1) and CB2 (cannabinoid receptor 2) in fasciae has not yet been established. Small samples of fascia were collected from volunteers patients during orthopedic surgery. For each sample were done a cell isolation, immunohistochemical investigation (CB1 and CB2 antibodies) and real time RT-PCR to detect the expression of CB1 and CB2. Both cannabinoid receptors are expressed in human fascia and in human fascial fibroblasts culture cells, although to a lesser extent than the control gene. We can assume that the expression of mRNA and protein of CB1 and CB2 receptors in fascial tissue are concentrated into the fibroblasts. This is the first demonstration that the fibroblasts of the muscular fasciae express CB1 and CB2. The presence of these receptors could help to provide a description of cannabinoid receptors distribution and to better explain the role of fasciae as pain generator and the efficacy of some fascial treatments. Indeed the endocannabinoid receptors of fascial fibroblasts can contribute to modulate the fascial fibrosis and inflammation.


Subject(s)
Fascia/metabolism , Fibroblasts/metabolism , Gene Expression Regulation/physiology , Receptor, Cannabinoid, CB1/biosynthesis , Receptor, Cannabinoid, CB2/biosynthesis , Aged , Aged, 80 and over , Fascia/cytology , Female , Fibroblasts/cytology , Humans , Male , Middle Aged
6.
Eur J Histochem ; 60(4): 2710, 2016 Nov 02.
Article in English | MEDLINE | ID: mdl-28076930

ABSTRACT

Many epidemiologic, clinical, and experimental findings point to sex differences in myofascial pain in view of the fact that adult women tend to have more myofascial problems with respect to men. It is possible that one of the stimuli to sensitization of fascial nociceptors could come from hormonal factors such as estrogen and relaxin, that are involved in extracellular matrix and collagen remodeling and thus contribute to functions of myofascial tissue. Immunohistochemical and molecular investigations (real-time PCR analysis) of relaxin receptor 1 (RXFP1) and estrogen receptor-alpha (ERα) localization were carried out on sample of human fascia collected from 8 volunteers patients during orthopedic surgery (all females, between 42 and 70 yrs, divided into pre- and post-menopausal groups), and in fibroblasts isolated from deep fascia, to examine both protein and RNA expression levels. We can assume that the two sex hormone receptors analyzed are expressed in all the human fascial districts examined and in fascial fibroblasts culture cells, to a lesser degree in the post-menopausal with respect to the pre-menopausal women. Hormone receptor expression was concentrated in the fibroblasts, and RXFP1 was also evident in blood vessels and nerves. Our results are the first demonstrating that the fibroblasts located within different districts of the muscular fasciae express sex hormone receptors and can help to explain the link between hormonal factors and myofascial pain. It is known, in fact, that estrogen and relaxin play a key role in extracellular matrix remodeling by inhibiting fibrosis and inflammatory activities, both important factors affecting fascial stiffness and sensitization of fascial nociceptors.


Subject(s)
Estrogen Receptor alpha/biosynthesis , Fascia/metabolism , Fibroblasts/metabolism , Gene Expression Regulation/physiology , Receptors, G-Protein-Coupled/biosynthesis , Receptors, Peptide/biosynthesis , Adult , Aged , Female , Humans , Middle Aged , Postmenopause/metabolism , Premenopause/metabolism
7.
Acta Otorhinolaryngol Ital ; 35(1): 49-52, 2015 Feb.
Article in English | MEDLINE | ID: mdl-26015652

ABSTRACT

We report a rare case of a large intraparotid facial nerve schwannoma (IFNS) in a 51-year-old female who presented with a painless, slow growing left parotid mass without peripheral facial nerve palsy, with non-specific findings at preoperative diagnostic work-up, that was treated with conservative surgery. Management of IFNS is very challenging because the diagnosis is often made intra-operatively, and in most cases resection may lead to severe facial nerve paralysis, with important aesthetic sequelae. Our experience suggests a new surgical option, namely intra-capsular enucleation using a microscope, currently used for schwannomas arising from a major peripheral nerve, which should be a safe and reliable treatment for IFNS. This surgical technique is the first experience of intracapsular microenucleation of facial nerve schwannoma described in the literature and allows preservation of the nerve without resection and reconstruction.


Subject(s)
Cranial Nerve Neoplasms/surgery , Facial Nerve Diseases/surgery , Neurilemmoma/surgery , Conservative Treatment , Female , Humans , Middle Aged , Neurosurgical Procedures/methods , Parotid Gland
8.
Eur J Histochem ; 58(2): 2360, 2014 May 12.
Article in English | MEDLINE | ID: mdl-24998924

ABSTRACT

Microfluidic, the technology that manipulates small amount of fluids in microscale complex devices, has undergone a remarkable development during the last decade, by targeting a significant range of applications, including biological tests and single-cell analysis, and by displaying many advantages such as reduced reagent consumption, decreased costs and faster analysis. Furthermore, the introduction of microfluidic tools has revolutionized the study of vascular functions, because the controlled three-dimensional environment and the continuous perfusion provided by the microdevice allow simulating the physiological characteristics of the circulatory system. Researchers interested in the study of vascular physiology, however, are often hampered by the difficulty in handling reduced number of cells after growth in these devices. This work shows how to apply different protocols commonly used in biology, such as the immunofluorescence technique, to cells grown in reversibly-bound microfluidic devices, obtaining results comparable to those retrieved under static conditions in multiwells. In this way, we are able to combine the advantages of microfluidic, i.e., application of continuous flow and shear stress, with classical protocols for the study of endothelial cells.


Subject(s)
Cell Culture Techniques , Human Umbilical Vein Endothelial Cells/cytology , Human Umbilical Vein Endothelial Cells/metabolism , Microfluidic Analytical Techniques , Cell Culture Techniques/instrumentation , Cell Culture Techniques/methods , Humans , Immunohistochemistry/instrumentation , Immunohistochemistry/methods , Microfluidic Analytical Techniques/instrumentation , Microfluidic Analytical Techniques/methods
9.
Acta Otorhinolaryngol Ital ; 32(1): 1-11, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22500060

ABSTRACT

The purpose of this report is to review the relationship between genetic polymorphisms involved in carcinogen metabolism, alcohol metabolism and cell-cycle control with the risk of head and neck cancer. The review was performed on available studies on genetic polymorphisms and head and neck cancer (HNC) published in PubMed up to September 2011. 246 primary articles and 7 meta-analyses were published. Among these, a statistically significant association was reported for glutathione S-transferases (GSTM1), glutathione S-transferases (GSTT1) and human microsomal epoxide hydrolase (EPHX1) genes. An increased risk for HNC was also associated reported for P53 codon 72 Pro/Pro, ALDH2 and three variants of the ADH gene: ADH1B (rs1229984), ADH7 (rs1573496) and ADH1C (rs698).


Subject(s)
Cell Cycle Checkpoints/genetics , Ethanol/metabolism , Head and Neck Neoplasms/epidemiology , Head and Neck Neoplasms/genetics , Polymorphism, Genetic , Head and Neck Neoplasms/metabolism , Humans , Metabolism/genetics , Molecular Epidemiology
10.
Histol Histopathol ; 22(3): 261-72, 2007 03.
Article in English | MEDLINE | ID: mdl-17163400

ABSTRACT

Detailed characterization of the subdermal model is a significant tool for better understanding of calcification mechanisms occurring in heart valves. In previous ultrastructural investigation on six-week-implantated aortic valve leaflets, modified pre-embedding glutaraldehyde-cuprolinic-blue reactions (GA-CB) enabled sample decalcification with concurrent retention/staining of lipid-containing polyanionic material, which lined cells and cell-derived matrix-vesicle-like bodies (phthalocyanin-positive layers: PPLs) co-localizing with the earliest apatite nucleation sites. Additional post-embedding silver staining (GA-CB-S) revealed PPLs to contain calcium-binding sites. This investigation concerns valve leaflets subjected to shorter implantation times to shed light on the modifications associated with PPLs generation and calcification onset/progression. Spectrometric estimations revealed time-dependent calcium increase, for unreacted samples, and copper modifications indicating an increase in acidic, non-glycanic material, for GA-CB-reacted samples. Two-day-implant thin sections showed emission and subsequent reabsorption of lamellipodium-like protrusions by cells, originating ECM-containing vacuoles, and/or degeneration stages characterized by the appearance of GA-CB-S-reactive, organule-derived dense bodies and progressive dissolution of all cell membranes. In one-week-implants, the first PPL-lined cells were found to co-exist with cells where GA-CB-S-reactive material accumulated, or exudated towards their edges, or outcropped at the ECM milieu, so acquiring PPL features. PPL-derived material was observed increasingly to affect the ECM on thin sections of one-week- to six-week-implants. These results show an endogenous source for PPLs and reveal that a peculiar cascade of cell degenerative steps is associated with valve mineralization in the subdermal model, providing new useful parameters for more reliable comparison of this experimental calcification process versus the physiological and pathological processes.


Subject(s)
Aortic Valve/ultrastructure , Calcinosis/pathology , Calcium/metabolism , Animals , Aortic Valve/metabolism , Aortic Valve/transplantation , Calcinosis/metabolism , Calcium/analysis , Disease Models, Animal , Immunohistochemistry , Male , Microscopy, Electron, Transmission , Rats , Rats, Sprague-Dawley , Silver Staining , Spectrometry, Mass, Electrospray Ionization , Swine , Time Factors
11.
Transplant Proc ; 37(1): 292-4, 2005.
Article in English | MEDLINE | ID: mdl-15808623

ABSTRACT

INTRODUCTION: We sought to use human mesenchymal stem cells (HMSC) for skin and spinal cord repair in mice. MATERIALS AND METHODS: Human bone marrow obtained from a young healthy donor was used to separate and culture human mesenchymal stem cells (HMSC). Ten mice were included in each of four groups. A full-thickness skin defect was surgically performed on all mice in groups 1 and 2. A transverse complete medullar section was performed in groups 3 and 4. Groups 1 and 3 received HMSC IV infusion and local HMSC polymer implant. Groups 2 and 4 received only the IV HMSC infusion. Five control animals from each group went through the same lesions but they didn't receive treatment. RESULTS: After local administration of HMSC into the fibrin polymer combined with the IV infusion of HMSC, there was no immune rejection; all skin defects healed without scar or retraction at a median time of 14 days. Sixty percent of the animals treated with IV infusion and polymer with HMSC simultaneously had improved neurological activities, while all control mice with spinal cord injury experiments died or perpetuated their paralysis with worsening muscular atrophy and increasing propensity to skin damage. CONCLUSIONS: HMSC are not immunologically reactive and can trespass species defense barriers. Animals treated with these cells repaired injuries better than controls. In this way we propose that universal HMSC from donors can be cultured, expanded, and cryopreserved to be used in human organ or tissue regeneration.


Subject(s)
Mesoderm/cytology , Skin/injuries , Spinal Cord Injuries/therapy , Stem Cell Transplantation , Stem Cells/cytology , Animals , Cell Culture Techniques/methods , Humans , Mice , Transplantation, Heterologous
12.
Prog. diagn. trat. prenat. (Ed. impr.) ; 16(4): 164-70, 2004. ilus, tab
Article in Spanish | IBECS | ID: ibc-152050

ABSTRACT

Introducción. El mielomeningocele representa una de las malformaciones congénitas más frecuentes y severas en humanos, que afecta aproximadamente a 1 de cada 2.000 recién nacidos en el mundo. Tiene una enorme significación médica y social, por la importante morbilidad a que se asocia, con gran cantidad de secuelas y un elevado coste en salud. Existe sólida evidencia que apoya la necesidad de tratamiento precoz. Dentro de las posibilidades de tratamiento actuales tiene especial interés la reparación quirúrgica durante la vida intrauterina. El trabajo con un modelo animal constituye el paso previo necesario a la intervención en humanos. Objetivos. En concordancia con otros grupos de investigadores, hemos elegido un modelo animal que permita conocer los resultados de la reparación de la columna vertebral en mielomenigoceles creados instrumentalmente. Material y métodos. Durante el período de mayo de 2002 hasta mayo de 2004 se ha reclutado un grupo de 23 ovejas de raza merina a las que se les realizó quirúrgicamente, a los 80 días de preñez, un mielomeningocele, realizando una laminectomía lumbar de 1 a 4 con apertura del canal medular y exposición del contenido al líquido amniótico. Las ovejas fueron aleatorizadas para ser incluidas en tres grupos: un grupo control y dos grupos de intervención. En uno de ellos se realizó una reparación neuroquirúrgica convencional y en el otro grupo se realizó una reparación colocando una membrana de tejido dérmico porcino acelular cultivado. Resultados. Los corderos del grupo control nacieron con manifestaciones clínicas severas de la enfermedad (tres de cinco corderos), con incapacidad en la deambulación e incontinencia de esfínteres; en los corderos de ambos grupos de intervención las manifestaciones clínicas de espina bífida fueron leves (cuatro de cinco corderos), con dificultad leve en la deambulación y continencia de esfínteres. Conclusiones. Los resultados alcanzados por el trabajo, debido al reducido número de intervenciones, no son concluyentes, pero muestran una tendencia a favor de la intervención de reparación intraútero del mielomeningocele. Las consecuencias de estos resultados en la práctica clínica deberán ser observadas a la luz de los resultados del Management of Myelomeningocele Study (MOMS) que se desarrolla actualmente en Estados Unidos en cuatro centros. Comentario final. La realización del presente trabajo ha tenido enorme significación para los autores ya que se ha reunido un equipo multidisciplinario que incluye anestesiólogos, neurocirujanos, neonatólogos, obstetras, veterinarios, enfermeros, neurólogos, etc., y se ha alcanzado el objetivo de adquirir nuevas destrezas que serán fundamentales para el manejo futuro de la cirugía fetal intraútero (AU)


Introduction. Myelomeningocele is one of the most frequent and severe congenital defects in humans, affecting approximately one in 2000 worldwide. This pathology is of great medical and social relevance due to its high morbidity, multiple sequela and high social cost. There is supporting evidence in favor of early treatment, particularly through intra uterine surgical correction. The work on animal models is a required preliminary step before intervention on humans. Objectives. In agreement with several other investigative groups we have chosen an animal model that allows us to know the results of spine correction in surgically induced myelomeningocele. Material and methods. Between may of 2002 and may of 2004 we recruited 23 sheep on which we induced myelomeningocele surgically at 80 days of gestational age, through 1 to 4 lumbar laminectomy with opening of bone marrow channel and exposure to amniotic fluid. AH sheep were randomized to be included in three groups: control group A, and intervention groups B (conventional intervention) and C (conventional plus noncellular porcine skin patch. Results. Neonate lambs (three out of five) in the control group presented with severe clinical disease related disabilities, namely walking impairment and incontinence. Lambs in B and C groups showed less severe impairment: slight walking handicap and lack of incontinence. Conclusions. Owing to the small sampling the results we reached are not conclusive, though they show a trend in favor of intrauterine correction of myelomeningocele. Relevance of these findings should be availed for clinical practice through the results from Management of Myelomeningocele Study (MOMS), currently ongoing in four UScenters. Final comment. The present trial represents an important advance for all participants in that it gathered a multidisciplinary team composed of anesthesiologists, neurosurgeons, pediatric neurosurgeons, obstetricians, pediatricians, vets, nurses, etc., and has led us to the acquisition of essential handskills for the future management of intra uterine fetal surgery (AU)


Subject(s)
Animals , Fetal Diseases/genetics , Fetal Diseases/pathology , Meningomyelocele/genetics , Spine/abnormalities , Hysterotomy/methods , Laminectomy/methods , Infant, Newborn/metabolism , Fetal Diseases/classification , Fetal Diseases/psychology , Meningomyelocele/pathology , Spine/metabolism , Hysterotomy/standards , Laminectomy/instrumentation , Infant, Newborn/physiology
13.
J Biomed Mater Res A ; 67(4): 1338-50, 2003 Dec 15.
Article in English | MEDLINE | ID: mdl-14624521

ABSTRACT

Extracellular matrix (ECM) scaffolds isolated from valvulated conduits can be useful in developing durable bioprostheses by tissue engineering provided that anatomical shape, architecture, and mechanical properties are preserved. As evidenced by SEM, intact scaffolds were derived from porcine aortic valves by the combined use of Triton X-100 and cholate (TRI-COL) or N-cetylpyridinium (CPC) and subsequent nucleic acid removal by nuclease. Both treatments were effective in removing most cells and all the cytomembranes, with preservation of (1) endothelium basal membranes, (2) ECM texture, including the D-periodical interaction of small proteoglycans with normally D-banded collagen fibrils, and (3) mechanical properties of the treated valves. Ultrastructural features agreed with DNA, hexosamine, and uronic acid biochemical estimations. Calcification potential, assessed by a 6-week rat subdermal model, was significantly reduced by TRI-COL/nuclease treatment. This was not true for CPC only, despite better proteoglycan preservation, suggesting that nucleic acids also are involved in calcification onset. Human fibroblasts, used to repopulate TRI-COL samples, formed mono- or multilayers on surfaces, and groups of cells also were scattered within the valve leaflet framework. A biocompatible scaffolds of this kind holds promise for production of durable valve bioprostheses that will be able to undergo probable turnover and/or remodeling by repopulating recipient cells.


Subject(s)
Aortic Valve/metabolism , Bioprosthesis , Calcification, Physiologic/physiology , Extracellular Matrix/metabolism , Heart Valve Prosthesis , Animals , Aortic Valve/ultrastructure , Culture Techniques , Fibroblasts/metabolism , Fibroblasts/ultrastructure , Humans , Male , Materials Testing , Nucleic Acids/metabolism , Rats , Rats, Sprague-Dawley , Stress, Mechanical , Swine , Tissue Engineering , Tissue Transplantation
14.
Histol Histopathol ; 18(4): 1131-40, 2003 10.
Article in English | MEDLINE | ID: mdl-12973682

ABSTRACT

Subdermal implant models are helpful in the study of calcification "in vivo" and for testing anticalcific treatments. After implantation of porcine aortic valve leaflets in rat subcutis, we previously found that glutaraldehyde-Cuprolinic blue reactions (GA-CB) at low pH induce favourable tissue unmasking from mineral deposits, and visualize peculiar, electrondense layers that outline the calcifying cells and matrix vesicle-like structures. The layer-forming material seemed to consist of acidic phospholipids because of its anionic nature and differential susceptibility to chemical/enzymatic extractivity. In the present investigation, pre-embedding glutaraldehyde-Malachite green (GA-MG) reactions and subsequent osmium post-fixation were compared with pre-embedding GA-CB reactions, combined with post-embedding von Kossa silver staining (GA-CB-S), to assess whether the layer-forming material is actually composed of acidic phospholipids and exhibits calcium-binding properties. After lowering standard pH, GA-MG reactions also caused sample demineralization and the appearance of pericellular osmium-MG-reactive layers comparable to CB-reactive ones. Moreover, GA-CB-S reactions showed that major silver precipitation was superimposed to the CB-reactive layers, whereas minor metal extra-precipitation occurred at three distinct, additional sites. These results demonstrate that a unique process of cell degeneration occurs in this calcification model, in which acidic phospholipids accumulate at cell surface, replacing cell membrane and acting as major apatite nucleator. However, the overall observations are consistent with the hypothesis that certain phases are common to the various types of normal and/or abnormal calcification.


Subject(s)
Aortic Valve/pathology , Bioprosthesis , Calcinosis/pathology , Coloring Agents/chemistry , Heart Valve Prosthesis , Indoles/chemistry , Phospholipids/chemistry , Phospholipids/physiology , Rosaniline Dyes/chemistry , Silver/chemistry , Animals , Fixatives , Glutaral/chemistry , Isoindoles , Male , Osmium Tetroxide , Paraffin Embedding , Phosphates/chemistry , Rats , Rats, Sprague-Dawley , Swine , Tissue Fixation/methods , Tolonium Chloride
15.
Eur J Ophthalmol ; 12(5): 401-5, 2002.
Article in English | MEDLINE | ID: mdl-12474923

ABSTRACT

PURPOSE: To evaluate, on eye bank eyes, a new surgical approach aimed at removing a quadrant of the trabecular meshwork (TM), with an ab interno approach. METHODS: Gonioscopically controlled ab interno removal of the TM was done with a subretinal forcep on six human bank eyes. Serial histological sections were obtained from the treated and untreated part of each globe to assess the effect of the technique on intraocular tissues. RESULTS: Under the gonioscope, the TM was easily removed in strings of varying length. Histological examination showed, unexpectedly, that this resulted in a well-defined deep furrow in the middle of the trabecular region involving both the TM and the inner wall of Schlemm's canal. The operation created a direct communication between the anterior chamber and Schlemm's canal lumen without any evident damage to the outer canal wall and adjacent ocular structures such as the iris base and corneal endothelium. CONCLUSIONS: Our small series on human bank eyes showed that the procedure involves both the TM and the inner wall of Schlemm's canal and is therefore called ab interno trabeculocanalectomy (AITC). The intraoperative findings and the histological evidence are encouraging, and suggest that the procecedure could have potential clinical application.


Subject(s)
Gonioscopy , Sclera/surgery , Trabeculectomy/methods , Cornea/pathology , Humans , In Vitro Techniques , Iris/pathology , Sclera/pathology
16.
Histochem J ; 34(1-2): 41-50, 2002.
Article in English | MEDLINE | ID: mdl-12365799

ABSTRACT

Previously, reactions with copper phthalocyanines at 0.05 M critical electrolyte concentration were found to cause demineralization in calcifying porcine aortic valves after subdermal implantation in rat, as well as simultaneous visualization of peculiar phthalocyanine-positive layers around cells and cell-derived matrix vesicles. In the present investigation, an appraisal was made of the mechanism and specificity of reactions with Cuprolinic Blue by comparing quantitatively calcium release and copper retention by calcified aortic valves reacted with this phthalocyanine under different critical electrolyte concentration conditions, and the corresponding ultrastructural patterns. It was found that (i) decalcifying properties are inversely proportional to salt molarity; (ii) reactivity to Cuprolinic Blue is critical electrolyte concentration-dependent, since the greatest copper retention occurred in 0.05 M critical electrolyte concentration Cuprolinic Blue-reacted samples, the only ones that also exhibited phthalocyanine-positive layers; (iii) the appearance of phthalocyanine-positive layers depends on Cuprolinic Blue uptake, revealing pericellular clustering of calcium-binding, anionic molecules; and (iv) minor Cuprolinic Blue uptake occurs by residual proteoglycans which still remain in the extracellular matrix after 6-week-long subdermal implantation. The present results indicate that this method is appropriate for the study of mineralized tissues and illustrate peculiar tissue modifications occurring at least in the experimental conditions used here.


Subject(s)
Aortic Valve/metabolism , Calcium/metabolism , Indoles/pharmacokinetics , Organometallic Compounds/pharmacokinetics , Animals , Aortic Valve/pathology , Aortic Valve/ultrastructure , Calcium/analysis , Calcium/chemistry , Extracellular Matrix/metabolism , Extracellular Matrix/ultrastructure , Indoles/analysis , Indoles/chemistry , Magnesium Chloride/pharmacology , Male , Mass Spectrometry , Microscopy, Electron , Nitric Acid/chemistry , Organometallic Compounds/analysis , Organometallic Compounds/chemistry , Proteoglycans/metabolism , Rats , Rats, Sprague-Dawley , Swine , Tissue Distribution , Uronic Acids/analysis
17.
Connect Tissue Res ; 43(1): 44-55, 2002.
Article in English | MEDLINE | ID: mdl-12180267

ABSTRACT

The roles played by various determinants in physiological, pathological or experimental calcification are still unclear. In this investigation, new insights were gained into structural changes occurring in porcine aortic valves undergoing mineralization in the rat subdermal model and then subjected to reactions with cationic phthalocyanines (PHTs), at salt-critical electrolyte concentrations (CEC). PHT reactions showed decalcifying effects, depending on both acidic pH in the media employed and mineral substitution by Cuprolinic Blue (CB) itself, as well as specific reactivity which enabled the ultrastructural detection of unusual, PHT-positive layers (PPLs) encircling cells and matrix vesicles, at 0.05 M CEC conditions. Other reactions at different CEC conditions, or subsequent to enzymatical or specific extractive treatments, suggest PPL appearance is due to PHT uptake by clustered anionic phospholipids, which seem to be involved in mineral precipitation. PPLs present as a novel, reliable ultrastructural parameter indicating cell propensity in priming experimental and, possibly, pathological calcification.


Subject(s)
Aortic Valve/transplantation , Aortic Valve/ultrastructure , Calcinosis/physiopathology , Graft Survival/physiology , Heart Valve Prosthesis Implantation/methods , Heart Valve Prosthesis/standards , Indoles , Animals , Aortic Valve/pathology , Chelating Agents , Dermis/metabolism , Dermis/surgery , Dermis/ultrastructure , Disease Models, Animal , Extracellular Matrix/metabolism , Extracellular Matrix/ultrastructure , Hydrogen-Ion Concentration , Isoindoles , Male , Microscopy, Electron , Organometallic Compounds , Rats , Rats, Sprague-Dawley , Swine
18.
Acta Gastroenterol Latinoam ; 31(3): 115-21, 2001.
Article in Spanish | MEDLINE | ID: mdl-11577562

ABSTRACT

INTRODUCTION: The action of non-steroidal anti-inflammatory drugs (NSAIDs) on the Helicobacter Pylori (Hp) infected mucosa is a matter of debate. Some authors consider them to cause additive iatrogeny whilst others attribute a purportedly protective action to them. The development of on experimental animal model could help clarify this phenomenon. OBJECTIVES: 1--To develop an animal model of Hp gastric infection. 2--To evaluate the aggressiveness of NSAIDs in this model. MATERIALS AND METHODS: Male 6 month old BALC/C mice weighing 38 g were studied. Pylori Hp infection was ruled out. On three occasions, in the same week, 18 mice were inoculated intra-gastrically with 0.6 ml of Hp culture broth (brain-heart infusion) containing 1 x 10 8-1 x 10 9 CFU/ml. Another group of mice were inoculated with sterile saline. After two months the mice were killed and their stomachs studied. They were divided into groups: a) 6 Hp negative control mice. b) 8 Hp negative mice with prior intra-peritoneal injection of 25 mg/Kg indomethacin (24 hs.) c) 8 mice inoculated with Hp with indomethacin. d) 8 mice inoculated with Hp, without indomethacin. The stomachs were opened along the greater curvature and photographed macroscopically in order to map the necrotic area. The antrums were biopsied to test for urease and separate antrum and body specimens were send for staining with Warthin-Starry H & B and histopathology. RESULTS: All the mice inoculated with Hp acquired the infection. The necrotic area was larger in Group B: 55.5 +/- 7.87 mm than in Group C: 15 +/- 1.82 mm P < 0.00019. HISTOLOGY: Group A: normal mucosa. Group B: extensive coagulation necrosis and focal erosions. Group C: ulcers with inflammatory infiltrate and smaller necrotic area, presence of Hp on the surface epithelium. Group D: no ulcers, Hp present. CONCLUSION: An animal model of Hp infection was successfully developed Hp infection could play a potentially protective role against indomethacin aggression in the mouse.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Disease Models, Animal , Gastric Mucosa/drug effects , Helicobacter Infections , Helicobacter pylori , Indomethacin/adverse effects , Animals , Gastric Mucosa/microbiology , Gastric Mucosa/pathology , Male , Mice , Mice, Inbred BALB C
19.
Rev. panam. flebol. linfol ; (42): 34-44, sept. 2001. ilus
Article in Spanish | LILACS | ID: lil-298853

ABSTRACT

La vedette actual de la escleroterapia es la Microespuma. Logramos inocular una "mousse" de esclerosante en dos especies animales-conejos y ovinos-obteniendo resultados sorprendentes. La fórmula detallada de la microespuma es no tóxica, de muy fácil manejo y por sobre todo económica. Se utilizaron estas dos especies animales por las siguientes razones:-La estructura histológica del endotelio vascular del conejo es la más semejante al humano.-Los conejos fueron inoculados para evaluar venas de pequeño calibre,0.4-1.5mm, mientras que los ovinos para evaluar venas de calibre medianoi, 1.5-3.0 mm aproximadamente


Subject(s)
Animals , Rabbits , Materials Testing , Butylene Glycols/therapeutic use , Sclerotherapy , Sclerotherapy/standards , Lymphatic System
20.
Rev. panam. flebol. linfol ; (42): 34-44, sept. 2001. ilus
Article in Spanish | BINACIS | ID: bin-9336

ABSTRACT

La vedette actual de la escleroterapia es la Microespuma. Logramos inocular una "mousse" de esclerosante en dos especies animales-conejos y ovinos-obteniendo resultados sorprendentes. La fórmula detallada de la microespuma es no tóxica, de muy fácil manejo y por sobre todo económica. Se utilizaron estas dos especies animales por las siguientes razones:-La estructura histológica del endotelio vascular del conejo es la más semejante al humano.-Los conejos fueron inoculados para evaluar venas de pequeño calibre,0.4-1.5mm, mientras que los ovinos para evaluar venas de calibre medianoi, 1.5-3.0 mm aproximadamente


Subject(s)
Animals , Rabbits , Sclerotherapy/methods , Sclerotherapy/standards , Materials Testing , Butylene Glycols/therapeutic use , Lymphatic System
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