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1.
Europace ; 26(4)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38571291

RESUMEN

AIMS: Same-day discharge (SDD) after atrial fibrillation (AF) ablation is an effective means to spare healthcare resources. However, safety remains a concern, and besides structural adaptations, SDD requires more efficient logistics and coordination. Therefore, in this study, we implement a streamlined, nurse-coordinated SDD programme following a standardized protocol. METHODS AND RESULTS: As a dedicated SDD coordinator, a nurse specialized in ambulatory cardiac interventions was in charge of the full SDD protocol, including eligibility, patient flow, in-hospital logistics, patient education, and discharge as well as early post-discharge follow-up by smartphone-based virtual visits. Patients planned for AF ablation were considered eligible if they had a left ventricular ejection fraction (LVEF) ≥35%, with basic support at home and accessibility of the hospital within 60 min also forming a part of the eligibility criteria. A total of 420 consecutive patients were screened by the SDD coordinator, of whom 331 were eligible for SDD. The reasons for exclusion were living remotely (29, 6.9%), lack of support at home (19, 4.5%), or LVEF <35% (17, 4.0%). Of the eligible patients, 300 (91%) were successfully discharged the same day. There were no major post-SDD complications. Rates of unplanned medical attention (19, 6.3%) and 30-day readmission (5, 1.6%) were extremely low and driven by femoral access-site complications. These were significantly reduced upon the introduction of compulsory ultrasound-guided punctures after the initial 150 SDD patients (P = 0.0145). Standardized SDD coordination resulted in efficient workflows and reduced the total workload of the medical staff. CONCLUSION: Same-day discharge after AF ablation following a nurse-coordinated standardized protocol is safe and efficient. The concept of ambulatory cardiac intervention nurses functioning as dedicated coordinators may be key in the future transition of hospitals to SDD. Ultrasound-guided femoral puncture virtually eliminated relevant femoral access-site complications in our cohort and should therefore be a prerequisite for SDD.


Asunto(s)
Fibrilación Atrial , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Alta del Paciente , Volumen Sistólico , Cuidados Posteriores , Función Ventricular Izquierda , Estudios Retrospectivos , Resultado del Tratamiento
2.
Am J Transplant ; 17(10): 2720-2727, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28510280

RESUMEN

Iatrogenic pancreatic cancer metastasis after islet infusion is a potential risk of islet autotransplantation performed after pancreatectomy. To model this risk, islets and/or pancreatic exocrine clusters obtained from a genetically engineered mouse model for pancreatic ductal adenocarcinoma (the LSL-KrasG12D/+ ;LSL-Trp53R172H/+ ;Pdx-1-Cre, termed KPC mouse) were transplanted via the portal vein in syngeneic wild type (WT) severely diabetic recipients in the following treatment groups: group A (n = 11) received KPC exocrine clusters in volume equal to 250 islet equivalents (IEQs); group B (n = 12) received 250 WT IEQs mixed with KPC exocrine clusters (1:1 volume ratio); group C (n = 5) received 250 KPC IEQs, and group D (n = 7) received 250 WT IEQs. The incidence of hepatic metastasis was assessed by magnetic resonance imaging and histology over the 13 months of follow-up. Overall survival was not different in the four groups. No mice developed liver metastases during the follow-up. Two mice developed spontaneous tumors: a liver hepatocellular tumor in group A and a malignant lymphoma in group D. Islets and/or exocrine clusters obtained by KPC mouse, a model that develops pancreatic cancer with 100% penetrance, do not retain the same risk of tumor development when transplanted via the portal vein in a syngeneic diabetic recipient.


Asunto(s)
Carcinoma Ductal Pancreático/etiología , Modelos Animales de Enfermedad , Enfermedad Iatrogénica , Trasplante de Islotes Pancreáticos/efectos adversos , Neoplasias Pancreáticas/etiología , Animales , Carcinoma Ductal Pancreático/patología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Neoplasias Pancreáticas/patología
3.
J Occup Environ Hyg ; 10(9): 461-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23915331

RESUMEN

The objective of this study was to assess how the relative efficiency of N95 respirators and surgical masks might vary with different challenge aerosols, utilizing a standardized manikin head form as a surrogate to human participation. A Collision nebulizer aerosolized B. anthracis Sterne strain endospores and polystyrene latex (PSL) particles to evaluate 11 models of N95 respirators and surgical masks. An automated breathing simulator, calibrated to normal tidal volume and active breathing rate, mimicked human respiration. A manikin head form with N95 respirators or surgical masks, and manikin head form without N95 respirators or surgical masks were placed in the bioaerosol chamber. An AGI-30 sampler filled with phosphate buffered water was fitted behind the mouth of each manikin head form to collect endospore bioaerosol samples. PSL aerosols concentrations were quantified by an ARTI Hand Held Particle Counter. Geometric Mean (GM) relative efficiency of N95 respirators and surgical masks challenged with endospore bioaerosol ranged from 34-65%. In PSL aerosol experiments, GM relative efficiency ranged from 35-64% for 1.3 µm particles. GM filtration efficiency of all N95 and surgical N95 respirators filter media evaluated was ≥99% when challenged with particles ≥0.1 µm. GM filtration efficiency of surgical mask filter media ranged from 70-83% with particles ≥0.1 µm and 74-92% with 1.3 µm PSL particles. Relative efficiencies of N95 respirators and surgical masks challenged with aerosolized B. anthracis endospores and PSL were similar. Relative efficiency was similar between N95 respirators and surgical masks on a manikin head form despite clear differences in filtration efficiency. This study further highlights the importance of face seal leakage in the respiratory protection provided by N95 respirators, and demonstrates it on a human surrogate.


Asunto(s)
Aerosoles/toxicidad , Bacillus anthracis , Exposición Profesional/prevención & control , Material Particulado/toxicidad , Dispositivos de Protección Respiratoria , Esporas Bacterianas , Filtración
4.
Food Microbiol ; 31(2): 309-12, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22608238

RESUMEN

Clostridium difficile is an anaerobic bacterium commonly considered to be responsible for antibiotic-associated gastrointestinal diseases, ranging from diarrhea of varying severity to pseudomembranous colitis. The aim of this study was to assess the occurrence of C. difficile in marine edible bivalve molluscs, which, as filter feeding organisms, are able to accumulate particles suspended in water, including microorganisms. Samples of Mytilus galloprovincialis, Tapes philippinarum, and Venus verrucosa were collected from mussel farms and fishmongers in the province of Naples (Southern Italy). C. difficile was found in 49% of the 53 samples investigated. Sixteen isolates were grouped in 12 known different PCR ribotypes (001, 002, 003, 010, 012, 014/020, 018, 045, 070, 078, 106, and 126), whereas 10 additional isolates were grouped in 8 new PCR riboprofiles. Two toxinotypes (0 and V) were found. Fifty eight percent of the isolates were toxigenic. These findings indicate that toxigenic C. difficile strains can be isolated in bivalve molluscs. Marine filter feeding organisms, therefore, may be considered as reservoir of toxigenic strains of C. difficile. The ingestion of raw or poorly cooked contaminated seafood and the high temperature resistance of the spore-forming C. difficile could represent an important source of exposure and pose human health concern.


Asunto(s)
Toxinas Bacterianas/metabolismo , Bivalvos/microbiología , Clostridioides difficile/aislamiento & purificación , Contaminación de Alimentos/análisis , Alimentos Marinos/microbiología , Animales , Toxinas Bacterianas/toxicidad , Bivalvos/clasificación , Clostridioides difficile/clasificación , Clostridioides difficile/genética , Clostridioides difficile/metabolismo , Alimentos Marinos/análisis
5.
Urol Int ; 86(1): 117-20, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20975257

RESUMEN

A 14-year-old boy presenting headache crisis, sweating and palpitation was observed. On ultrasound scan, a 3 × 2.5 cm hypoechoic mass, highly vascularized, was observed arising from the left bladder wall. Magnetic resonance imaging confirmed the mass situated close to the ureteral orifice, with intense peripheral enhancement and a central non-enhanced portion. Left partial cystectomy was performed. Large clear cells, presenting cytoplasmatic granules positive for S100 and chromogranin, were observed at histology. Bladder paraganglioma derives from chromaffin tissue of the sympathic system and it is uncommon in children. The estimated prevalence is very low (0.06% of bladder tumors). Symptomatology is related to the catecholamine production. In pediatrics, prognosis is usually good but long-term follow-up is required.


Asunto(s)
Paraganglioma/patología , Paraganglioma/cirugía , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/cirugía , Adolescente , Humanos , Masculino
6.
Eur Ann Otorhinolaryngol Head Neck Dis ; 138(1): 13-17, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32703738

RESUMEN

OBJECTIVES: The study objective was to compare patient satisfaction after thyroid lobo-isthmectomy under hypnoanesthesia versus general anesthesia. METHODS: A retrospective study included 100 patients undergoing lobo-isthmectomy. A group of 50 patients under hypnoanesthesia was compared to a control group of 50 patients under general anesthesia. Satisfaction was assessed on questionnaire between three and six months after surgery. We also compared secondary criteria: procedure time, blood loss, intraoperative comfort, postoperative pain, postoperative complications and time to resumption of daily activities. RESULTS: Our study showed good overall satisfaction in patients operated under hypnoanesthesia, for equivalent operative safety and complications rate compared to general anesthesia. For comparable analgesia, postoperative pain was lower, but not significantly, in the Hypnosis group, while the rate of nausea and vomiting was significantly lower (p<0.05). Postoperative convalescence was shorter in the Hypnosis group: 3.7 versus 9.2 days (p<0.001). CONCLUSION: In thyroid surgery, hypnoanesthesia has real advantages over general anesthesia in that it places the patient at the center of the care team's attention. His or her active participation is essential during the process, bringing a new dimension to care, beneficial for the patient. However, it must be reserved for minimally invasive procedures in which organization is anticipated in full collaboration within teams that are willing and experienced.


Asunto(s)
Hipnosis , Glándula Tiroides , Anestesia General , Femenino , Humanos , Masculino , Dolor Postoperatorio , Estudios Retrospectivos
7.
J Cardiovasc Med (Hagerstown) ; 22(1): 29-35, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33186239

RESUMEN

INTRODUCTION: During the coronavirus disease-19 (COVID-19) outbreak in spring 2020, people may have been reluctant to seek medical care fearing infection. We aimed to assess the number, characteristics and in-hospital course of patients admitted for acute cardiovascular diseases during the COVID-19 outbreak. METHODS: We enrolled all consecutive patients admitted urgently for acute myocardial infarction, heart failure or arrhythmias from 1 March to 31 May 2020 (outbreak period) and 2019 (control period). We evaluated the time from symptoms onset to presentation, clinical conditions at admission, length of hospitalization, in-hospital medical procedures and outcome. The combined primary end point included in-hospital death for cardiovascular causes, urgent heart transplant or discharge with a ventricular assist device. RESULTS: A similar number of admissions were observed in 2020 (N = 210) compared with 2019 (N = 207). Baseline characteristics of patients were also similar. In 2020, a significantly higher number of patients presented more than 6 h after symptoms onset (57 versus 38%, P < 0.001) and with signs of heart failure (33 versus 20%, P = 0.018), required urgent surgery (13 versus 5%, P = 0.004) and ventilatory support (26 versus 13%, P < 0.001). Hospitalization duration was longer in 2020 (median 10 versus 8 days, P = 0.03). The primary end point was met by 19 (9.0%) patients in 2020 versus 10 (4.8%) in 2019 (P = 0.09). CONCLUSION: Despite the similar number and types of unplanned admissions for acute cardiac conditions during the 2020 COVID-19 outbreak compared with the same period in 2019, we observed a higher number of patients presenting late after symptoms onset as well as longer and more complicated clinical courses.


Asunto(s)
Arritmias Cardíacas/epidemiología , COVID-19/epidemiología , Insuficiencia Cardíaca/epidemiología , Hospitalización/estadística & datos numéricos , Infarto del Miocardio con Elevación del ST/epidemiología , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Femenino , Hospitales de Enseñanza , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Pandemias
9.
Neuroscience ; 153(4): 1354-69, 2008 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-18448256

RESUMEN

Dissociated cortical neurons from rat embryos cultured onto micro-electrode arrays exhibit characteristic patterns of electrophysiological activity, ranging from isolated spikes in the first days of development to highly synchronized bursts after 3-4 weeks in vitro. In this work we analyzed these features by considering the approach proposed by the self-organized criticality theory: we found that networks of dissociated cortical neurons also generate spontaneous events of spreading activity, previously observed in cortical slices, in the form of neuronal avalanches. Choosing an appropriate time scale of observation to detect such neuronal avalanches, we studied the dynamics by considering the spontaneous activity during acute recordings in mature cultures and following the development of the network. We observed different behaviors, i.e. sub-critical, critical or super-critical distributions of avalanche sizes and durations, depending on both the age and the development of cultures. In order to clarify this variability, neuronal avalanches were correlated with other statistical parameters describing the global activity of the network. Criticality was found in correspondence to medium synchronization among bursts and high ratio between bursting and spiking activity. Then, the action of specific drugs affecting global bursting dynamics (i.e. acetylcholine and bicuculline) was investigated to confirm the correlation between criticality and regulated balance between synchronization and variability in the bursting activity. Finally, a computational model of neuronal network was developed in order to interpret the experimental results and understand which parameters (e.g. connectivity, excitability) influence the distribution of avalanches. In summary, cortical neurons preserve their capability to self-organize in an effective network even when dissociated and cultured in vitro. The distribution of avalanche features seems to be critical in those cultures displaying medium synchronization among bursts and poor random spiking activity, as confirmed by chemical manipulation experiments and modeling studies.


Asunto(s)
Corteza Cerebral/citología , Red Nerviosa/fisiología , Neuronas/fisiología , Acetilcolina/farmacología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Animales , Células Cultivadas , Embrión de Mamíferos , Modelos Neurológicos , Red Nerviosa/efectos de los fármacos , Neuronas/efectos de los fármacos , Ratas , Factores de Tiempo
10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 3076-3079, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30441044

RESUMEN

Intracortical microstimulation can be successfully used to manipulate neuronal activity and connectivity, thus representing a potentially powerful tool to steer neuroplasticity occurring after brain injury. Activity-dependent stimulation (ADS), in which the spikes recorded from a single neuron are used to trigger stimulation at another cortical location, is able to potentiate cortical connections between distant brain areas. Here, we developed an experimental procedure and a computational pipeline aimed at investigating the ability of ADS to induce changes in intra-cortical activity of healthy anesthetized rats.


Asunto(s)
Neuronas , Animales , Encéfalo , Estimulación Eléctrica , Plasticidad Neuronal , Ratas
11.
Eur J Histochem ; 51 Suppl 1: 9-14, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17703588

RESUMEN

Tendons transmit forces generated from muscle to bone making joint movements possible. Tendon collagen has a complex supramolecular structure forming many hierarchical levels of association; its main functional unit is the collagen fibril forming fibers and fascicles. Since tendons are enclosed by loose connective sheaths in continuity with muscle sheaths, it is likely that tendon sheaths could play a role in absorbing/transmitting the forces created by muscle contraction. In this study rat Achilles tendons were passively stretched in vivo to be observed at polarized light microscope (PLM), scanning electron microscope (SEM) and transmission electron microscope (TEM). At PLM tendon collagen fibers in relaxed rat Achilles tendons ran straight and parallel, showing a periodic crimp pattern. Similarly tendon sheaths showed apparent crimps. At higher magnification SEM and TEM revealed that in each tendon crimp large and heterogeneous collagen fibrils running straight and parallel suddenly changed their direction undergoing localized and variable modifications. These fibril modifications were named fibrillar crimps. Tendon sheaths displayed small and uniform fibrils running parallel with a wavy course without any ultrastructural aspects of crimp. Since in passively stretched Achilles tendons fibrillar crimps were still observed, it is likely that during the tendon stretching, and presumably during the tendon elongation in muscle contraction, the fibrillar crimp may be the real structural component of the tendon crimp acting as shock absorber. The peritendinous sheath can be stretched as tendon, but is not actively involved in the mechanism of shock absorber as the fibrillar crimp. The different functional behaviour of tendons and sheaths may be due to the different structural and molecular arrangement of their fibrils.


Asunto(s)
Tendón Calcáneo/fisiología , Fenómenos Biomecánicos , Tendón Calcáneo/ultraestructura , Animales , Femenino , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Microscopía de Polarización , Ratas , Ratas Sprague-Dawley , Traumatismos de los Tendones , Resistencia a la Tracción
12.
Knee ; 14(2): 87-93, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17188877

RESUMEN

Following anterior cruciate ligament (ACL) reconstruction with the middle third part patellar tendon, the graft undergoes histological rearrangement due to biomechanical action, which transforms it into a structure similar to the normal ACL. The purpose of our study was to make a qualitative and quantitative histological evaluation, by transmission electron microscopy (TEM), of the neoligamentization process of a bone-patellar tendon-bone (BTPB) graft used as pro-ACL at different follow-up times. We analysed the ultrastructure of collagen fibrils by focusing on their size and distribution with respect to a normal patellar tendon and a normal ACL used as controls. Our results showed that up to 24 months follow-up, progressive ultrastructural changes towards the normal ACL were observed. At longer times after surgery (48 and 120 months) no further changes were evident and the ultrastructure showed a marked reduction in large fibrils, which was typical of the control patellar tendon, and a significant increase in small fibrils. The ultrastructure seemed to combine fibrils from two different morphological units. The BPTB graft used as ACL underwent a transformation process for up to two years. After that period the transformation ceased and for ten years failed to reach the ultrastructural aspect of a normal ACL. However, from an architectural point of view the graft was slowly transformed into a structure similar to ACL with respect to the different mechanical stresses the ligament has to sustain.


Asunto(s)
Ligamento Cruzado Anterior/cirugía , Plastía con Hueso-Tendón Rotuliano-Hueso/patología , Ligamento Rotuliano/ultraestructura , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior , Estudios de Casos y Controles , Colágeno/ultraestructura , Tejido Elástico/ultraestructura , Elastina/ultraestructura , Proteínas de la Matriz Extracelular/ultraestructura , Estudios de Seguimiento , Humanos , Masculino , Microscopía Electrónica de Transmisión
13.
Environ Health Perspect ; 114(7): 1032-7, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16835055

RESUMEN

OBJECTIVE: In this study we evaluated the levels of antibiotic- and multidrug-resistant bacteria in bioaerosols upwind, within, and downwind at locations 25 m, 50 m, 100 m, and 150 m from a swine confined animal feeding operation. DESIGN: We used Andersen two-stage samplers to collect bacterial samples, the replicate plate method to isolate organisms, and the Kirby-Bauer disk diffusion method to determine antibiotic resistance. RESULTS: The percentage of organisms resistant to at least two antibiotic classes and all four classes evaluated were, respectively, 2.1 and 3.0 times higher inside (n = 69) than upwind (n = 59) of the facility. Staphylococcus aureus was the most prevalent organism recovered. Concentrations of antibiotic-resistant S. aureus decreased with increasing distance from the facility. Using Fisher's exact methods, the change in distribution of antibiotic resistance profiles for each antibiotic was statistically significant (oxytetracycline, p = 0.010; tetracycline, p = 0.014; ampicillin, p = 0.007; erythromycin, p = 0.035); however, this relationship was not seen with lincomycin and penicillin (p > 0.05) . In addition, the levels of antibiotic-resistant S.aureus 25 m downwind were significantly greater than the levels from samples taken upwind from the facility for the same four antibiotics (p < 0.05) . The percentage of resistant group A streptococci and fecal coliform increased within the facility compared with upwind values for all antibiotics evaluated,except for lincomycin. The percentage of resistant total coliform organisms increased within the facility compared with upwind values for oxytetracycline and tetracycline. CONCLUSIONS: Bacterial concentrations with multiple antibiotic resistances or multidrug resistance were recovered inside and outside to (at least) 150 m downwind of this facility at higher percentages than upwind. Bacterial concentrations with multiple antibiotic resistances were found within and downwind of the facility even after subtherapeutic antibiotics were discontinued. This could pose a potential human health effect for those who work within or live in close proximity to these facilities.


Asunto(s)
Aire Acondicionado , Microbiología del Aire , Alimentación Animal , Crianza de Animales Domésticos , Farmacorresistencia Bacteriana , Porcinos/microbiología , Animales , Vivienda para Animales
14.
Biomaterials ; 15(6): 433-7, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8080934

RESUMEN

Heat-deproteinated bone (calcined bone) is a natural candidate for an osteoreproductive biomaterial. Ultrastructural investigation has pointed out an important aspect of the preparation technique. Treatment of bone at temperatures exceeding 500 degrees C causes complete disruption of the tissue architecture and the reorganization of the mineral phase into tightly packed, dense crystals. At 500 degrees C or less the structure and distribution of the mineral phase remain unaffected, so that cross-banded 'shadows' of collagen fibrils are still readily observable, although collagen is no longer present in the samples. By its excellent structural preservation and natural porosity, low-temperature calcined bone seems to be a promising alternative for osteoreproduction.


Asunto(s)
Materiales Biocompatibles , Huesos/ultraestructura , Calor , Animales , Bovinos , Cristalización , Fémur , Microscopía Electrónica de Transmisión de Rastreo , Porosidad
15.
Biomaterials ; 20(4): 363-70, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10048409

RESUMEN

Biomaterials may initiate several and complex biological reactions in host tissues, and the cell-biomaterial interactions can determine the release of mediators including monocytes and lymphocytes chemotactic factors. The present work was aimed to investigate in vitro the macrophage biological reactions of a natural apatite obtained by heat treatment at 400 degrees C of bovine bone, compared to other ceramics usually used for dental and orthopedic applications, using synthetic apatite and three types of alumina as controls. Particles chemotactic activity and powders oxidative burst evidenced no monocyte macrophages sensitivity reaction for natural and synthetic hydroxyapatite powders at great granulometry (> 50 microm); data were confirmed by ultrastructural observations; electron microscopy analysis showed macrophages with the features of healthy cells in the presence of both natural and synthetic apatites while macrophages grown in the presence of alumina seemed to be negatively affected. In conclusion, among all ceramics tested, natural apatite displayed a good compatibility with living cells, being better tolerated than synthetic hydroxyapatite which in turn is better tolerated than alumina.


Asunto(s)
Materiales Biocompatibles/farmacología , Cerámica/farmacología , Hidroxiapatitas/farmacología , Macrófagos Peritoneales/efectos de los fármacos , Óxido de Aluminio/farmacología , Animales , Apatitas/síntesis química , Apatitas/farmacología , Bovinos , Cerámica/química , Quimiotaxis de Leucocito/efectos de los fármacos , Humanos , Mediciones Luminiscentes , Macrófagos Peritoneales/fisiología , Macrófagos Peritoneales/ultraestructura , Ratones , Ratones Endogámicos BALB C , Monocitos/efectos de los fármacos , Monocitos/fisiología , Monocitos/ultraestructura
16.
Biomaterials ; 25(12): 2239-46, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-14741589

RESUMEN

Titanium (Ti) endosseous dental screws with different surfaces (smooth titanium--STi, titanium plasma-sprayed-TPS, alumina oxide sandblasted and acid-etched--Al-SLA, zirconium oxide sandblasted and acid etched--Zr-SLA) were implanted in femura and tibiae of sheep to investigate the biological evolution of the peri-implant tissues and detachment of Ti debris from the implant surfaces in early healing. Implants were not loaded. Sections of the screws and the peri-implant tissues obtained by sawing and grinding were analysed by light microscopy immediately after implantation (time 0) and after 14 days. All samples showed new bone trabeculae and vascularised medullary spaces in those areas where gaps between the implants and host bone were visible. In contrast, no osteogenesis was induced in the areas where the implants were initially positioned in close contact with the host bone. Chips of the pre-existing bone inducing new peri-implant neo-osteogenesis were surrounded by new bone trabeculae. The threads of some screws appeared to be deformed where the host bone showed fractures. Ti granules of 3-60 microm were detectable only in the peri-implant tissues of TPS implants both immediately after surgery and after 14 days, thus suggesting that this phenomenon may be related to the friction of the TPS coating during surgical insertion.


Asunto(s)
Tornillos Óseos/efectos adversos , Implantación Dental/efectos adversos , Implantes Dentales de Diente Único/efectos adversos , Fémur/patología , Cuerpos Extraños/patología , Tibia/patología , Titanio , Animales , Materiales Biocompatibles Revestidos/efectos adversos , Análisis de Falla de Equipo , Fémur/cirugía , Cuerpos Extraños/etiología , Tamaño de la Partícula , Falla de Prótesis , Propiedades de Superficie , Tibia/cirugía
17.
Biomaterials ; 24(7): 1309-16, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12527273

RESUMEN

The shape, surface composition and morphology of orthopaedic and endosseous dental titanium implants are key factors to achieve post-surgical and long-term mechanical stability and enhance implant osteointegration. In this study a comparison was made between 12 titanium screws, plasma-spray-coated with titanium powders (TPS), and 12 screws with an additional coating of fluorohydroxyapatite (FHA-Ti). Screws were implanted in the femoral and tibial diaphyses of two mongrel sheep and removed with peri-implant tissues 12 weeks after surgery. The vibrational spectroscopic, ultrastructural and morphological analyses showed good osteointegration for both types of implants in host cortical bone. The portion of the FHA-Ti implants in contact with the medullary canal showed a wider area of newly formed peri-implant bone than that of the TPS implants. Morphological and EDAX analyses demonstrated the presence of small titanium debris in the bone medullary spaces near the TPS surface, presumably due to the friction between the host bone and the implant during insertion. Few traces of titanium were detected around FHA-Ti implants, even if smaller FHA debris were present. The present findings suggest that the FHA coating may act as a barrier against the detachment of titanium debris stored in the medullary spaces near the implant surface.


Asunto(s)
Aleaciones Dentales/química , Implantes Dentales , Hidroxiapatitas , Prótesis e Implantes , Titanio , Animales , Implantación Dental Endoósea , Diseño de Prótesis Dental , Fémur/anatomía & histología , Fémur/cirugía , Microscopía Electrónica de Rastreo , Ovinos , Propiedades de Superficie , Tibia/anatomía & histología , Tibia/cirugía
18.
J Psychosom Res ; 52(2): 61-3, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11832250

RESUMEN

The aim of this study was to investigate the relationship between cholesterol and mood states in the initial puerperal period. The Profile of Mood States (POMS) was administered to 72 women on the third day after normal pregnancy, uncomplicated vaginal delivery and healthy baby. Plasma cholesterol concentration was measured the same day. Our study indicates that reduced plasma cholesterol concentration is associated with major feelings of fatigue and depressed mood. The implications of these results are discussed.


Asunto(s)
Afecto , Colesterol/sangre , Periodo Posparto/psicología , Adulto , Depresión/psicología , Femenino , Humanos , Trastornos del Humor/psicología , Embarazo
19.
Comp Immunol Microbiol Infect Dis ; 23(1): 53-72, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10660258

RESUMEN

A survey was undertaken to examine sea water and sediment for the presence of Vibrio and Aeromonas spp. along approximately 900 km of coast in Southern Italy during early and late summer. A quantitative analysis was also done to evaluate the water fecal contamination at the stations examined. The results indicate that all the investigated areas were submitted to a wide spatial fluctuation of fecal contamination and that Vibrio and Aeromonas spp. were present in both high and low fecal-contaminated stations. Sixty two percent of the investigated samples were positive for Aeromonas spp., while 42% of samples were positive for Vibrio spp. It was interesting to note that 38% of the positive stations for both Aeromonas and Vibrio spp. showed a fecal coliform contamination of water at < 10(2) cells 100 ml(-1). Thus, these findings support the hypothesis that the bacterial indicators (such as fecal coliforms) do not always satisfactorily reflect the hygienic quality of water. The presence of Vibrionaceae on copepods was also investigated. Copepods were sampled at a station located inside the harbour of the city of Naples and were found contaminated by V. cholerae non-O1, V. alginolyticus, V. fluvialis and A. caviae. Furthermore, the antibiotic resistance patterns of isolated bacteria showed the presence of a number of resistant strains among the isolates. In order to discriminate the isolates on the basis of their biochemical profiles and/or antibiotic resistance patterns, cluster analysis was carried out which showed that no unique assay could fully discern these isolates. However, the best discrimination resulted from complete pattern profile based on both biochemical profiles and antibiotic resistance patterns.


Asunto(s)
Aeromonas/crecimiento & desarrollo , Agua de Mar/microbiología , Vibrio/crecimiento & desarrollo , Microbiología del Agua , Aeromonas/genética , Animales , Análisis por Conglomerados , Crustáceos/microbiología , Farmacorresistencia Microbiana , Enterobacteriaceae/química , Heces/microbiología , Sedimentos Geológicos , Italia , Microscopía Electrónica de Rastreo , Filogenia , Vibrio/genética
20.
Comp Immunol Microbiol Infect Dis ; 19(3): 245-54, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8800550

RESUMEN

The colonisation of planktonic copepod integument by bacteria belonging to the family of Vibrionaceae is a well described phenomenon. In this study, besides reporting on the occurrence of Vibrionaceae and other enteropathogens, we further report on the bacterial attachment to the Estuarine copepod Acartia margalefi in a faecal polluted coastal lagoon near Naples, Southern Italy. In addition, we also performed a laboratory experiment to study the ability of 7 bacterial strains (Vibrio cholerae non-Ol, V. mimicus, V. parahaemolyticus, V. alginolyticus, Aeromonas hydrophila, Escherichia coli and Pseudomonas sp.) to colonise the copepod integument. For this laboratory study, 4 different species of copepods, namely Temora stylifera, A. clausi, Centropages typicus and Paracalanus parvus sampled from the Gulf of Naples (Southern Italy) were used. Scanning electron microscope (SEM) studies on the copepods sampled from the lagoon indicated that the bacterial attachment on the integument of Acartia margalefi was mainly on the ventro-lateral body region of the host and in the joints of the thoracic segments, as well as on the swimming and feeding appendages. This infestation, made by rod-like bacteria, was absent in winter but reached peak values of 70% frequency in June. The laboratory studies showed that while V. cholerae non-O1 and A. hydrophila attached on live and dead copepods, respectively, the V. parahaemolyticus, V. alginolyticus, V. mimicus, E. coli and Pseudomonas sp. failed to colonise either live or dead copepods. Thus, this study provides further valuable information about the ecological relationship between different microorganisms (pathogens) and copepods in the coastal marine environment in Southern Italy.


Asunto(s)
Aeromonas , Crustáceos/microbiología , Ecología , Agua de Mar , Vibrio , Microbiología del Agua , Animales , Italia , Microscopía Electrónica de Rastreo/veterinaria
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