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At least 1,135 records · Page 63Linked to original sources
PubMed2006

Attrition of military enlistees with a medical waiver for myopia, 1999-2001.

BACKGROUND: Military service requires physical fitness, including vision within set standards. Premature attrition inflicts a considerable manpower and fiscal burden upon the military. METHODS: We conducted a retrospective cohort survival analysis of newly enlisted military personnel who entered active duty with a medical waiver for myopia between January 1, 1999, and December 31, 2001. Premature attrition rates, both medical and overall, were compared with those for a matched, fully qualified, comparison group. RESULTS: New enlistees with a waiver for myopia had the same probability of remaining on active duty through the first 2 years of service as did fully qualified peers. Enlistees with a waiver for myopia also had a low probability of an early medical discharge for myopia. CONCLUSION: The results of this study tend to validate the current branch-specific myopia waiver processes. They also provide evidence that current myopia accession criteria may be too restrictive and in need of policy review.

Adolescent↗
PubMed1999

Iliorenal bypass for the treatment of type-3 Takayasu's disease. A case report with 10-year follow-up.

The case of a 16-year old female with severe renovascular hypertension resulting from type-3 Takayasu's arteritis is reported. The entire thoracic and abdominal aorta was affected by an active inflammatory process and all its branches were stenotic or occluded. After the early failure of a percutaneous balloon angioplasty of the left renal artery, an iliac to renal artery bypass graft using a reversed autologous saphenous vein was performed through a retroperitoneal tunnel The patient is asymptomatic and the graft is patent at 10-year follow-up.

Adolescent↗
PubMedDate not supplied

Helping supervisors step into the educator's role.

Supervisors who lack the skills of the educator rarely visualize training as an integral part of their jobs. Consequently, new employees suffer from poor instruction and supervisors miss out on a potentially rewarding aspect of their duties. Seeking to remedy this situation, the University of Texas Medical Branch Department of Sterile Processing and Central Supply and the Personnel Office tailored a train-the-trainer program to meet the specific needs of their supervisors.

Administrative Personnel↗
PubMed2002

Efficient recolonisation of progenitor-depleted areas of the CNS by adult oligodendrocyte progenitor cells.

A widely quoted hypothesis for the failure of remyelination in multiple sclerosis (MS) is the exhaustion of the oligodendrocyte progenitor cell (OPC) pool that is strongly implicated as the source of remyelinating oligodendrocytes in demyelinating lesions. Despite this, little is known about the responses of adult OPCs to adjacent areas of the CNS from which their numbers are depleted. We have developed an experimental model to study the pattern and rate of repopulation of OPC-depleted zones, by endogenous OPCs in the adult rat spinal cord. By X-irradiating short lengths of the spinal cord with 40 Gy of X-irradiation, we were able to produce a highly localised depletion of OPCs that allowed us to study the responses of cells located in adjacent normal areas, to this local depletion. Using both NG2 immunohistochemistry and PDGFalphaR in situ hybridisation to identify OPCs, we demonstrate that endogenous OPCs repopulated the depleted areas slowly, but completely. This repopulation occurred at the rate of approximately 0.5 mm/week in the first month. Most cells at the leading edge of repopulation had complex, branching morphologies. The repopulation process was capable of restoring the density of progenitors in repopulated areas to that of normal tissue and was not associated with a secondary progenitor loss in tissue from which progenitor cells were generated. These findings indicate that depletion of the OPC population around lesions is not likely to be the primary explanation for remyelination failure in MS.

Animals↗
PubMed1987

Mineral deposits formation in bioactive IUD's.

Mineral organic deposits have been observed in inert IUDs. The authors studied the presence of these deposits in bioactive IUDs. Inert, progesterone, and copper-releasing IUDs were removed at 12,24, and 36 months postinsertion. When the devices were cut between their vertical (body) and horizontal (arms) branches, both parts were processed independently. After laxly bound organic material was eliminated, the devices were extracted at 60 degrees Celsius for 90 minutes with 3N HC1, and finally all undissolved material was dissolved in 1N NaOH. In each fraction, protein and inorganic ions were measured. Mineral organic deposits were formed in all types of IUDs. The deposits increased with time in utero in a characteristic device-dependent pattern. The deposits were essentially made of proteins, sodium, and calcium ions and were higher on the inert Lippes Loop D (7.0 +or- 2.4 mg proteins; 2.8 +or- 0.85 mg calcium, and 0.138 +or- 0.048 mg sodium/device); less in the copper IUD (5.7 +or- 1.36 mg proteins, 0.89 +or- 0.12 mg calcium, and 0.180 +or- 0.046 mg sodium/device at 24 months); and even less in the progesterone-releasing IUDs (1.6 +or- 1.3 mg protein, 0.235 +or- 0.028 mg calcium, and 0.262 +or- 0.063 mg sodium/device).

Calcium↗
PubMed1976

[Indicatory and technical faults as cause of postoperative complications in arterial surgery].

In all vascular surgery the technic and quality of the first operation is a factor of decisive importance for the long-term results. The need to perform a second or third operation considerably reduces the chances of success. Routine use of an intra-operative control method like arteriography or vascular endoscopy, makes a decisive contribution in the peripheral circulation of the limbs to the immediate detection of errors of operative technic and their correction during the same operation. A change of indication for occlusive processes in the femoropopliteal branch is evident: patients with claudication should be treated with profunda revascularisation combined with lumbal sympathectomy and patients with rest-pain and necrosis should be treated with venous autografts using a microsurgical technic. To avoid deep wound infections the selection of an incision line which does not damage the lymphatic channels, particularly in the groin, the short duration of operations and the use of a purely instrumental operative technic with minimal damage to the tissues are of decisive importance. Examples are used to illustrate errors of indication and technic and the post-operative sequelae of such errors.

Aortic Aneurysm↗
PubMed1992

The human anterior cruciate ligament: histological and ultrastructural observations.

In transverse and longitudinal paraffin-embedded sections, the human anterior cruciate ligament (ACL) is made up of wavy bundles of collagen fibres arrayed in various directions, the majority around the axis of the ligament with a few running parallel to it. The fascicles making up the larger bundles are also characterised by this undulating appearance. In thin sections 2 types of collagen fibrils are observed: small (with a single diameter peak at 45 nm) and large (3 peaks at 35, 50 and 75 nm respectively), organised into distinct areas made up of either large or small bundles of fibrils. The numerous fibroblasts that are present appear elongated in the direction of the bundles with branches and short cytoplasmic processes. The elastic system is made up of both elastic and oxytalan fibres. The varied orientation of the bundles in the ACL, the complex ultrastructural organisation and the abundant elastic system make it very different from other ligaments and tendons, providing a structure able to withstand the multiaxial stresses and varying tensile strains imposed upon it.

Anterior Cruciate Ligament↗
PubMed2004

[Recent rhinos do not lack character(s): neither do fossil rhinos!].

Concepts, methods, and interest of phylogenetic reconstruction are briefly examined. As large data sets are considered and refutable results are proposed, there is no need to use the argument of authority concerning relationships between taxons. Cladistic analysis in vertebrate palaeontology has gained considerable strength in the last decade, based on sets of hundreds of anatomical characters. One example is selected, which concerns the rhino family, i.e. rhinocerotids. Although underrepresented in recent times, these perissodactyl mammals flourished throughout the Cenozoicera (4 recent genera vs. 50 fossil genera). The main results of a recent cladistic analysis of elasmotheriine rhinocerotids, based on 282 anatomical characters, are listed. Such results concern phylogenetics (monophyly of both elasmotheriines and recent rhinos; branching of elasmotheriines among rhinocerotids) and methodology (definition of a "branching group"; location and processing of homoplasy; influence of taxonomic sampling). The implications are both biostratigraphical and palaeobiogeographical (evolution of the diet and spatial distribution; intercontinental dispersals; ghost lineages and heuristic use of the phylogenetic tree). Finally, forthcoming developments of the available data set for rhinocerotids are examined: controversial phylogenetic relationships among recent rhinos will be refined (thanks to close extinct taxa) and an exhaustive phylogeny of fossil and recent rhinocerotids will be reconstructed (54 genera).

Animals↗
PubMed1990

Classification of the syndromes of branchial arches 1 and 2.

On the basis of observations of 393 patients over many years, the author considers it possible to distinguish 5 types among the various forms of the syndrome of branchial arches 1 and 2. Two types are characteristic of the syndrome of branchial arch 1: the mandibular type and the mandibuloauricular type. The former is unilateral and occurs very rarely, the latter is encountered more frequently and can be unilateral or bilateral. For the syndrome of branchial arches 1 and 2, three types are characteristic: the auricular, the mandibulofacial and auricular, and the craniofacial, articular and auricular. The auricular type is mainly characterized by marked anomalies of the cochlea and the sense of hearing, occurs most frequently of all and is also bilateral. The mandibulofacial and auricular type exhibits more pronounced affections of both the cochlea and hearing and the bones of the facial skeleton. It occurs frequently and is unilateral. The craniofacial, articular and auricular type shows the most serious combinations of defects of the cochlea, the base of skull, the temporal bone, the facial skeleton, and the absence of the branch and the condylar process of mandible as well as hypoplasia of the soft tissues of the face. Systemic dysplasias of the face, the jaws and the cochlea are combined with defects of other, frequently distant, systems.

Abnormalities, Multiple↗
PubMed1991

Inhibition of angiogenesis in vitro by Arg-Gly-Asp-containing synthetic peptide.

This study was designed to evaluate the effect of the synthetic peptide Gly-Arg-Gly-Asp-Ser (GRGDS) on angiogenesis in serum-free collagen gel culture of rat aorta. The GRGDS peptide contains the amino acid sequence Arg-Gly-Asp (RGD), which has been implicated as a recognition site in interactions between extracellular matrix (ECM) molecules and cell membrane receptors. RGD-containing synthetic peptides are known to inhibit attachment of endothelial cells to substrates, but their effect on angiogenesis has not been fully characterized. Aortic explants embedded in collagen gel in the absence of GRGDS generated branching microvessels through a process of endothelial migration and proliferation. Addition of GRGDS to the culture medium caused a marked inhibition of angiogenesis. In contrast, GRGES, a control peptide lacking the RGD sequence, failed to inhibit angiogenesis. The inhibitory effect of GRGDS was nontoxic and reversible. The angiogenic activity of aortic explants previously inhibited with GRGDS could be restored by incubating the cultures in GRGDS-free medium. These findings suggest that angiogenesis is an anchorage-dependent process that can be inhibited by interfering with the attachment of endothelial cells to the ECM. It also indicates that synthetic peptides can be used as probes to study the mechanisms by which the ECM regulates angiogenesis.

Amino Acid Sequence↗
PubMed1986

Fate of brachial muscles of the chick embryo innervated by inappropriate nerves: structural, functional and histochemical analyses.

The extent of interaction between brachial muscles and foreign (thoracic) nerves of the chick embryo was determined during an extended period of development in ovo from the perspectives of innervation pattern, function (motility analyses), muscle growth (quantitative analyses of muscle volume) and fibre-type expression (myosin-ATPase profiles). Results indicated that according to all parameters analysed, initially a compatible union existed between the foreign nerves and their muscle targets. During subsequent stages of development, deterioration of the once compatible relationship emerged, until eventually denervation of muscles, i.e. an actual loss of intramuscular nerve branches, was observed. The process of denervation, which proceeded at a differential rate among individual muscles, however was restricted to brachial muscles derived from the premuscle masses of the wing bud. In contrast, brachial muscles of myotomal origin were spared the fate of wing-bud-derived muscles and maintained a successful union with the foreign nerves.

Adenosine Triphosphatases↗
PubMed1988

Effects of laminin on attachment, growth and differentiation of cultured Y-79 retinoblastoma cells.

In vitro, as in vivo, the attachment, growth and differentiation of many cell types are dependent upon the availability of appropriate extracellular matrix (ECM) molecules. Here we have studied the effects of ECM components, including fibronectin and laminin on cultured Y-79 retinoblastoma cells. Both in 2 hr and in 3 day studies, the highest frequencies of attachment were seen with a laminin substrate (50 micrograms/35 mm culture dish). Attachment was significantly inhibited by specific anti-laminin antibodies. In longer studies of up to 1 week, laminin or fibronectin was added directly to the culture medium. Neither molecule significantly stimulated cell growth, but laminin continued to promote the highest frequencies of attachment (20% to 30% greater than any other substrate). Laminin exposure also caused morphological changes in Y-79 cells. Many cells became flattened and extended long, branching, neurite-like processes. These changes could be inhibited by inclusion of anti-laminin antibodies. Such studies may provide information about events occurring during normal eye development as well as about tumor cell attachment and growth.

Animals↗
PubMedDate not supplied

The gelatinous plaque: its relation to coronary atherosclerosis.

The relations between the gelatinous plaque and the atherosclerotic plaque were investigated on more than 500 subjects aged 1--40 years. The appearance of the light microscopic aspect of the gelatinous plaque was related to a particular: a) evolution of the process of histolysis involving branch pads and thickened intimas; b) insudation, occurring in nodular proliferations of intimal smooth muscle cells; c) stage of atheroma formation. The results showed that the term gelatinous plaque did not refer to an independent, early atherosclerotic lesion, or a true precursor of advanced lesions,but to an intermediate, transitional stage in the complex histogenesis of the atherosclerotic plaque.

Adolescent↗
PubMed1995

Spontaneous rupture of a pancreatic pseudocyst into the portal vein.

An unusual complication of pancreatic pseudocyst is reported. A 47-year-old woman with chronic liver disease and a history of recurrent pancreatitis died of fulminant, gram-negative septic shock. Acute, bilateral thigh cellulitis with tissue culture positive for Escherichia coli was the only potential infectious source identified. Autopsy revealed a pseudocyst in the head of the pancreas that had eroded into the portal vein, with embolization of mucoid cyst material into intrahepatic portal vein branches. Fibrous organization and recanalization of some of the occluded portal vein branches indicated that this process had been present for weeks to months and was therefore not the direct cause of death. The literature on this unusual complication of pancreatic pseudocyst is also reviewed.

Female↗
PubMed1993

Control of neuronal morphogenesis by homeoproteins: consequences for the making of neuronal networks.

To test whether homeoproteins can act as genetic regulators in the processes of neurite growth, branching, guidance, and connectivity, the 60 amino acid homeodomain of Antennapedia was introduced in embryonic neurons in primary culture. It was hoped that this homeopeptide would bind to specific promoters and thus behave as a competitive inhibitor of endogenous homeoproteins. The introduction of the homeodomain in the nerve cells was made easy by its unexpected capability to translocate through the membranes and to accumulate within the nuclei. The presence of the homeodomain within the cells correlated with an increase in neurite growth and branching. The absence of activity of mutant peptides, still internalized but unable to bind with high affinity to homeoprotein cognate binding sites, strongly suggested that endogenous homeoproteins modulate neurite outgrowth and branching. Moreover, the efficient internalization of the homeobox peptide by live cells in culture raises the possibility that, in addition to their well-established role as cell-autonomous transcription factors, some homeoproteins may also exert paracrine functions. We examine how these hypotheses could modify our current views on the establishment and plasticity of neuronal networks.

Animals↗
PubMed1998

Müller (glial) cells in the teleost retina: consequences of continuous growth.

In the continuously enlarging eye of teleost fishes retinal growth is achieved by the generation of new cells and by stretching the existing tissue. As a consequence of stretching, the density for most neurons decreases except for rod photoreceptors, which are produced by stem cells in the outer nuclear layer (ONL). We investigated retinal Müller glial cells with immunocytochemical markers against vimentin and glutamine synthetase in animals of various sizes. In addition, we used Western immunoblot analysis to investigate the changes in the glia-specific enzyme glutamine synthetase in the enlarging retina. We found that in the cichlid fish Haplochromis burtoni the density of Müller cells decreases from about 14 cells/mm2 to 4 cells/mm2 with increasing body size. Since it is known that the density of rod photoreceptors remains constant, it follows that the neuron to Müller cell ratio increases in the growing eye. In our estimates, this ratio ranges from around 54:1 in small fish to more than 67:1 in larger animals. Quantified Western blots revealed that the amount of glutamine synthetase per retinal area does not change in the growing eye, which means that the amount of this enzyme in each Müller cell must increase. Staining isolated cells and retinal sections from small and large fish with an antibody against glutamine synthetase showed stronger immunoreactivity in larger animals, especially in the areas of the photoreceptor cell bodies and outer limiting membrane and a more extensive branching of Müller cell processes. Thus, Müller cells in growing fish appear to compensate for the increasing metabolic challenge and are able to maintain their function.

Animals↗
PubMed1998

[Deep venous thrombosis in a patient with superficial thrombophlebitis. Apropos of 2 cases].

Deep vein thrombosis in patient with superficial thrombophlebitis of the leg. Description of two cases. Two clinical cases already observed at our Department of Vascular Surgery, regarding patients with superficial thrombophlebitis (STF) associated with a deep venous thrombosis (DVT) are presented. The diagnosis of DVT was achieved exclusively on the basis of the duplex scanner because the two patients were completely asymptomatic. The chance that symptoms and clinical signs of STF cover a DVT is a possibility that should always be considered. For this reason every STF should be further investigated with duplex scanner in order to exclude that the deep venous circulation get involved at the same time. The DVT in these cases is generally due to the spreading of the thrombosis process from the perforating branches. The chance of a multiple onset of thrombosis in the superficial and deep circulation represents anyway an hypothesis worth of studying.

Adult↗