Las huelgas de los estibadores portuarios en el sur santafesino en 1928

El 2 de mayo de 1928 se inicia una huelga de estibadores portuarios en Rosario después de años de tibia actividad sindical. Días más tarde, varios hechos de sangre provocaron la solidaridad obrera con dos paros generales que conmovieron a la ciudad por su agitación y violencia. Los portuarios villenses también se solidarizaron y, un mes más tarde, encabezaron un violento reclamo laboral. El motivo inicial de las huelgas fue el salarial, pero la cuestión de fondo que hilvana a ambas experiencias es la puja social por el deterioro de las condiciones laborales y las imposiciones empresarias en el control y selección de la fuerza de trabajo.En principio la espontaneidad de la protesta tomó por sorpresa a las organizaciones sindicales de izquierda que durante la década del 20 habían mostraban varias fracturas, no obstante será la oportunidad que explica la reorganización y difusión del movimiento obrero con posterioridad. En otro sentido, los conflictos en Rosario y Villa Constitución reflejan la compleja trama de la política santafesina y su conexión con el ámbito laboral. Asimismo, creemos que los sucesos de 1928 tienen una repercusión mayor que la estrictamente local engarzándose en un ciclo de conflictividad que involucra a buena parte de la economía agroexportadora

Tendinitis rotuliana y pliometría en juniors de alto rendimiento

Habitualmente los trabajos y estudios publicados sobre el entrenamiento de la potencia pliométrica de miembros inferiores orientados hacia el alto rendimiento deportivo en baloncesto, son realizados sobre atletas de elite, pero no así sobre jugadores que están en la etapa del traspaso de las categorías Junior a las Elites, pero que, en muchos casos, entrenan juntos, sin que se respete su individualidad biológica, llevando en muchos casos a lesiones tendinosas por un inadecuado trabajo metodológico en estas etapas (15 a 17 años). Por otra parte se ha buscado desarrollar una serie de indicaciones metodológicos para favorecer la prevención de lesiones osteo-articulares en esta etapa de camino hacia el Alto Rendimiento. La rodilla de saltador, también conocida como tendinitis rotuliana o tendinopatía rotuliana, es una inflamación o lesión del tendón rotuliano, un tejido similar a una cuerda que une la rótula a la tibia (hueso de la espinilla). La rodilla de saltador es una lesión por sobrecarga (movimientos repetidos que causan irritación o daño en los tejidos en determinada zona del cuerpo). Saltar, caer y cambiar de dirección de manera constante pueden provocar torceduras, desgarros y daño en el tendón rotuliano. Por lo tanto, los jóvenes que regularmente practican deportes que implican saltar mucho todo el tiempo, como el baloncesto, pueden ejercer mucha presión en las rodillas. La rodilla de saltador puede parecer una lesión menor que no es realmente grave. Por este motivo, muchos jugadores siguen entrenando y compitiendo, y suelen ignorar la lesión o intentan tratarla por su cuenta

La rodilla : Influencias anatomofuncionales en su biomecánica

Un conocimiento minucioso de la articulación de la rodilla interesa al profesor en educación física, por ser la articulación más utilizada, más expuesta, y menos protegida en las actividades de la vida diaria. La articulación de la rodilla además de unir el fémur, la tibia y la rótula, es un elemento de alta complejidad mecánica en cuanto a su anatomía a pesar de estar dotada de un solo sentido de libertad de movimiento: la flexión-extensión. De manera accesoria, posee un segundo sentido de movimientos: la rotación sobre el eje longitudinal de la pierna, que solo aparece cuando la rodilla ha sido flexionada. Asimismo los músculos que la rodean y actúan sobre ella tienen la capacidad no solo de ejecutar los movimientos normales, sino también, según su tono, modificar la alineación de los segmentos óseos en la postura estática. A través del siguiente trabajo, no solo se tratara de describir aspectos de la biomecánica de la rodilla, sino la relación que presentan todos los elementos anatómicos que la rodean y que influyen en su funcionamiento, determinando la importancia que lleva este conocimiento en cada actividad planteada desde la educación física

Haploinsufficiency of Sox9 results in defective cartilage primordia and premature skeletal mineralization

In humans, SOX9 heterozygous mutations cause the severe skeletal dysmorphology syndrome campomelic dysplasia. Except for clinical descriptions, little is known about the pathogenesis of this disease. We have generated heterozygous Sox9 mutant mice that phenocopy most of the skeletal abnormalities of this syndrome. The Sox9+/− mice died perinatally with cleft palate, as well as hypoplasia and bending of many skeletal structures derived from cartilage precursors. In embryonic day (E)14.5 heterozygous embryos, bending of radius, ulna, and tibia cartilages was already prominent. In E12.5 heterozygotes, all skeletal elements visualized by using Alcian blue were smaller. In addition, the overall levels of Col2a1 RNA at E10.5 and E12.5 were lower than in wild-type embryos. We propose that the skeletal abnormalities observed at later embryonic stages were caused by delayed or defective precartilaginous condensations. Furthermore, in E18.5 embryos and in newborn heterozygotes, premature mineralization occurred in many bones, including vertebrae and some craniofacial bones. Because Sox9 is not expressed in the mineralized portion of the growth plate, this premature mineralization is very likely the consequence of allele insufficiency existing in cells of the growth plate that express Sox9. Because the hypertrophic zone of the heterozygous Sox9 mutants was larger than that of wild-type mice, we propose that Sox9 also has a role in regulating the transition to hypertrophic chondrocytes in the growth plate. Despite the severe hypoplasia of cartilages, the overall organization and cellular composition of the growth plate were otherwise normal. Our results suggest the hypothesis that two critical steps of the chondrocyte differentiation pathway are sensitive to Sox9 dosage. First, an early step presumably at the stage of mesenchymal condensation of cartilage primordia, and second, a later step preceding the transition of chondrocytes into hypertrophic chondrocytes.

Effects of estrogen on growth plate senescence and epiphyseal fusion

Estrogen is critical for epiphyseal fusion in both young men and women. In this study, we explored the cellular mechanisms by which estrogen causes this phenomenon. Juvenile ovariectomized female rabbits received either 70 μg/kg estradiol cypionate or vehicle i.m. once a week. Growth plates from the proximal tibia, distal tibia, and distal femur were analyzed after 2, 4, 6, or 8 weeks of treatment. In vehicle-treated animals, there was a gradual senescent decline in tibial growth rate, rate of chondrocyte proliferation, growth plate height, number of proliferative chondrocytes, number of hypertrophic chondrocytes, size of terminal hypertrophic chondrocytes, and column density. Estrogen treatment accelerated the senescent decline in all of these parameters. In senescent growth plates, epiphyseal fusion was observed to be an abrupt event in which all remaining chondrocytes were rapidly replaced by bone elements. Fusion occurred when the rate of chondrocyte proliferation approached zero. Estrogen caused this proliferative exhaustion and fusion to occur earlier. Our data suggest that (i) epiphyseal fusion is triggered when the proliferative potential of growth plate chondrocytes is exhausted; and (ii) estrogen does not induce growth plate ossification directly; instead, estrogen accelerates the programmed senescence of the growth plate, thus causing earlier proliferative exhaustion and consequently earlier fusion.

Variabilidad de la estancia media en pacientes hospitalizados en un hospital de Traumatología durante el año 2010

Objetivos: El objetivo principal del estudio es conocer la estancia media hospitalaria y su variabilidad en relación con el motivo de ingreso, en una unidad de hospitalización de un hospital monográfico de Traumatología. (Unión de Mutuas. Castellón) Metodología: Estudio transversal, descriptivo, basado en datos administrativos, cuya población estuvo formada por todos los individuos que tuvieron algún episodio de hospitalización durante el año 2010, siendo este el criterio de inclusión, por orden cronológico de aparición. Resultados: Se identificaron un total de 736 episodios asistenciales y 133 códigos CIE-9CM. La edad media fue 44 (+/-10) años. El 83,25% de los pacientes fueron varones. El código 836.0 (Desgarro de cartílago o menisco interno de la rodilla-actual) fue el diagnóstico más habitual (12,25%) y la artroscopia la técnica quirúrgica mayoritaria. “Fractura de pelvis” (CIE-9CM 808) resultó el código diagnóstico que presentó mayor estancia media con 25 (+/-9.84) estancias y mayor variabilidad de la misma, seguido de los diagnósticos “Fractura de diáfisis de tibia-cerrada”, “Fractura de diáfisis de tibia/peronéabierta”, “Contusión de múltiples sitios, ncoc” y “Fractura de tibia y peroné”. Conclusiones: Se observa poca variabilidad en la estancia media excepto en los procesos diagnosticados como fractura de pelvis y en los relacionados con fracturas de los miembros inferiores.

Una década de noticias de prensa sobre poliomielitis en la provincia de Guadalajara (1958–1967)

El período de más incidencia de la poliomielitis en España corresponde a los años de 1950 a 1963. La vacuna inactivada antipolio de Salk estuvo disponible a partir de 1955 y varios países la adoptaron para combatir la enfermedad. La actitud de las autoridades sanitarias españolas para abordar el problema fue tibia e ineficaz, sin dar una respuesta decidida para implementar la vacuna de modo sistemático. Hemos realizado un estudio de caso explorando las noticias sobre polio recogidas en dos semanarios de la provincia de Guadalajara durante el decenio de 1958–1967. Los resultados revelan una acumulación de informaciones sesgada y contradictoria, que refleja la incapacidad para tomar decisiones. Desde la negación de la enfermedad y las dudas sobre la vacuna Salk en el primer período, se pasa a la exaltación de la vacuna oral de Sabin, cuando ésta mostró su evidencia tras aplicarla en la campaña de 1963–1964, y que las autoridades se atribuyeron este éxito tardío con una fuerte propaganda mediática.

Valutazione sperimentale in-vitro di nuove superfici protesiche per la sostituzione totale di caviglia derivanti da un innovativo approccio morfologico

La sostituzione totale di caviglia o artroplastica totale di caviglia (Total Ankle Replacement - TAR) è un'operazione eseguita per sostituire le superfici di contatto delle ossa di tibia e astragalo mediante componenti protesiche e sta diventando una comune procedura chirurgica per il trattamento dell’ultimo stadio di osteoartrite di caviglia. La morfologia articolare della caviglia e la relativa cinematica sono molto complesse. Gli attuali dispositivi per TAR soffrono ancora di alti tassi di insoddisfazione e fallimento, probabilmente a causa dei relativi disegni protesici non pienamente rispettosi della normale morfologia di caviglia e del normale trasferimento dei carichi articolari. Recentemente, è stato proposto un nuovo disegno basato su un originale postulato che approssima la superficie articolare talare in modo maggiormente fisiologico, come un tronco di cono a sella con apice diretto lateralmente. L'obiettivo di questa tesi di laurea è di valutare sperimentalmente, mediante il supporto del navigatore chirurgico, il comportamento cinematico derivante dall’impianto del dispositivo TAR basato sul nuovo postulato e di confrontarlo con la cinematica derivante dalla caviglia intatta e derivante da modelli protesici basati sui disegni più comunemente utilizzati. Dieci arti inferiori da cadavere con caviglie intatte e normali, sono state scansionati via CT. Le immagini di caviglia sono state poi segmentate per la produzione dei modelli virtuali articolari. Questi sono stati prodotti sia basandosi sul nuovo postulato sia su quelli standard, e successivamente stampati in materiale plastico via 3D-printing. I risultati ottenuti a seguito di elaborazioni confermano che il nuovo dispositivo sembra riprodurre meglio rispetto agli altri, il fisiologico comportamento funzionale della caviglia, presentando valori prossimi a quelli della caviglia naturale.

Proton pump inhibitors and the risk of fractures in older adults: a population-based retrospective cohort study

Thesis (Master's)--University of Washington, 2016-06

Changes in joint stability with muscle contraction measured from transmission of mechanical vibration

A non-invasive in vivo technique was developed to evaluate changes in wrist joint stability properties induced by increased co-activation of the forearm muscles in a gripping task. Mechanical vibration at 45, 50 and 55 Hz was applied to the radial head in ten healthy volunteers. Vibrations of the styloid process of the radius and the distal end of the metacarpal bone of the index finger were measured with triaxial accelerometers. Joint stability properties were quantified by the transfer function gain between accelerations on either side of the wrist-joint. Gain was calculated with the muscles at rest and at five force levels ranging from 5% to 25% of maximum grip force (%MF). During contraction the gain was significantly greater than in control trial (0%MF) for all contractions levels at 45 and 50 Hz and a trend for 15%MF and higher at 55 Hz. Group means of contraction force and gain were significantly correlated at 45 (R-2 = 0.98) and 50 Hz (R-2 = 0.72), but not at 55 Hz (R-2 = 0.10). In conclusion, vibration transmission gain may provide a method to evaluate changes in joint stability properties. (c) 2005 Published by Elsevier Ltd.

Developmental Pathways in Microcerotermes turneri (Termitidae: Termitinae): Biometric Descriptors of Worker Caste and Instar

The foraging process of location and exploitation of food in complex termite societies is in part reliant upon unequal division of specific tasks amongst its members (polyethism). To conduct studies assessing the role of individuals in foraging activities it is necessary to have descriptors of worker caste and instar. Here we provide biometric descriptors of specific caste and instar for worker caste and instars of Microcerotermes turneri (Froggatt) (Termitidae: Termitinae) for the worker castes (male and female) for the identification of individuals in laboratory assays applicable across multiple nests. The use of head width for determining sex of workers was successful across multiple nests. The length of the first three flagellum segments of the antenna and tibia three could be used to determine worker instar.

What does the animal model teach us about the effects of physical activity on growing bone?

Experiments to design physical activity programs that optimize their osteogenic potential are difficult to accomplish in humans. The aim of this article is to review the contributions that animal studies have made to knowledge of the loading conditions that are osteogenic to the skeleton during growth, as well as to consider to what extent animal studies fail to provide valid models of physical activity and skeletal maturation. Controlled loading studies demonstrate that static loads are ineffective, and that bone formation is threshold driven and dependent on strain rate, amplitude, and duration of loading. Only a few loading cycles per session are required, and distributed bouts are more osteogenic than sessions of long duration. Finally, animal models fail to inform us of the most appropriate ways to account for the variations in biological maturation that occur in our studies of children and adolescents, requiring the use of techniques for studying human growth and development.

3D statistical shape models to embed spatial relationship information

This paper presents the creation of 3D statistical shape models of the knee bones and their use to embed information into a segmentation system for MRIs of the knee. We propose utilising the strong spatial relationship between the cartilages and the bones in the knee by embedding this information into the created models. This information can then be used to automate the initialisation of segmentation algorithms for the cartilages. The approach used to automatically generate the 3D statistical shape models of the bones is based on the point distribution model optimisation framework of Davies. Our implementation of this scheme uses a parameterized surface extraction algorithm, which is used as the basis for the optimisation scheme that automatically creates the 3D statistical shape models. The current approach is illustrated by generating 3D statistical shape models of the patella, tibia and femoral bones from a segmented database of the knee. The use of these models to embed spatial relationship information to aid in the automation of segmentation algorithms for the cartilages is then illustrated.

Vitamin E-stabilised UHMWPE for orthopaedic implants:quantitative determination of vitamin E and characterisation of its transformation products

The fate of vitamin E and the formation and identification of its transformation products were investigated at different stages of the manufacturing process of commercially produced cross-linked (by γ-irradiation) UHMWPE stabilised with vitamin E (vitamin E infused-post irradiation) used for tibia-components (as articulating surfaces) in total knee arthroplasty (total knee replacement). Vitamin E (α-tocopherol) and its transformation products were extracted from microtomed Tibia films and the different products were separated, isolated, purified using high performance liquid chromatography (HPLC), and characterised by spectroscopic methods and LC-MS. The amount of vitamin E and that of the products formed in the different Tibia samples and in their extracts were also quantified using FTIR and HPLC analysis and calibration curves. Thorough analysis of the Tibia extracts has shown that a number of vitamin E transformation products were formed at different concentrations at two selected stages of the implant manufacturing process that is before and after sterilisation by γ-irradiation. The identified products were found to correspond mainly to different stereoisomeric forms of a small number of vitamin E transformation products. Most of the observed products were of dimeric and trimeric nature with their identity confirmed through a detailed study of their spectral and chromatographic characteristics. It was found that the products of vitamin E, prior to the sterilisation step but after the crosslinking and doping of vitamin E, were mainly the dihydroxydimers and trimers (Tibia samples at this stage are referred to as “Tibia-VEPE”). After sterilisation and completion of the manufacturing process, additional dimers of vitamin E were also formed (Tibia samples at this stage are referred to as ‘Tibia-VEPE-Sterile’), Furthermore, two tocopherol-derived aldehydes (aldehyde 5-formyl-γ-tocopherol and aldehyde 7-formyl-γ-tocopherol) were also formed but at very low concentrations especially in the Tibia-VEPE-Sterile samples. The question of whether vitamin E becomes chemically reacted (grafted) onto the polymer matrix during the manufacturing process of the Tibia is also addressed.

Stima delle forze di reazione piede-suolo durante la corsa tramite sensori inerziali

Per investigare i carichi sopportati dal corpo nella vita di tutti i giorni, è neccesario un metodo semplice per la stima delle forze di reazione piede-suolo (GRFs) . In questo studio viene presentato un modello per stimare l’andamento delle GRFs durante la corsa, a partire dalle accelerazioni misurate tramite sensori inerziali. I due soggetti che hanno partecipato all’esperimento hanno corso a 4 diverse velocità predefinite e indossato cinque sensori: uno su pelvi, due su tibia (destra e sinistra) e due su piede (destro e sinitro). A partire dai dati ottenuti è stato elaborato un modello che stima l’andamento delle GRFs (verticali e anteroposteriori) e i tempi di contatto e volo del passo tramite l’accelerazione assiale tibiale. Per la stima delle forze di reazione viene utilizzato un modello di stima basato sui tempi di contatto e volo, unito ad un modello che prevede la presenza o meno e il modulo degli impact peak sfruttando due picchi negativi individuati nelle accelerazioni assiali tibiali. Sono state utilizzate due pedane di carico come gold standard per valutare la qualità delle stime ottenute. Il modello prevede correttamente la presenza dell'impact peak nell'85% dei casi, con un errore sul modulo compreso fra il 6% e il 9%. Le GRFs verticali massime vengono approssimate con un errore fra l'1% e 5%, mentre le GRFs antero-posteriori con un errore fra l'8% e il 14% del range massimo-minimo del segnale.