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PubMed1997

Voluntary scapulothoracic subluxation: a case report.

Dislocation of the scapula is a rare event, usually associated with massive trauma and injury. We report a case of a patient for whom dislocation was the sole presentation. The possibility of voluntary dislocation for secondary gain was suspected, but because of perceived progressive brachial plexus involvement, urgent closed reduction was undertaken and led to resolution of the neurologic symptoms. The patient returned 1 year later with similar complaints and findings, but declined another closed reduction attempt when offered only an interscalene regional block as pain relief. The diagnosis of voluntary dislocation should be considered in a patient presenting with superior and lateral migration of the scapula, without a history of trauma.

Adult↗

PubMed1985

Monocyte function following surgery in man. Increased numbers and stimulation of migration, phagocytosis and chemiluminescence following abdominal surgery.

The whole blood monocyte count (WBMC), migratory response (MMR), phagocytosis (MPI), chemiluminescence (MCL) and serum opsonic activity (SOA) were measured in patients undergoing elective surgery. The WBMC, MMR, MPI and MCL increased significantly at 24 h after operation in patients undergoing abdominal surgery with a moderate fall at 48 h and a return to normal values at 1 week; the SOA was little altered. In patients undergoing minor surgery the WBMC was also increased after surgery but the MMR was unchanged. The finding that certain monocyte functions are increased after surgery contrasts with studies showing that reticulo-endothelial clearance is depressed in the post-operative period.

Abdomen↗

PubMed2003

Alteration of migration and maturation of dendritic cells and T-cell depletion in the course of experimental Trypanosoma cruzi infection.

Trypanosoma cruzi, the etiologic agent of Chagas disease, induces infection that affects most immunocompetent cells. However, its effect on dendritic cells (DC) is still unknown in vivo. In this report, we show, by immunohistochemical staining, that T. cruzi infection triggers a huge increase in the number of CD11c(+) DC in the spleen of infected mice at Days 14 and 21 post-inoculation (pi). In mice reaching the chronic phase (starting on Day 35 pi), the number of splenic DC (sDC) returned progressively to normal (ending on Day 98 pi). In the spleens of noninfected mice, most of the CD8alpha(+)CD11c(+) and CD8alpha(-)CD11c(+) DC were found in the red pulp and the marginal and T-cell zones. However, starting on Day 14 pi, a progressive decline of CD8alpha(+)CD11c(+) was observed. In addition, sDC expressed low levels of the costimulatory molecule B7.2 at Days 14 and 21 pi, suggesting that they remained immature in the course of the infection. As expected, in lipopolysaccharide-treated and noninfected mice, the expression of B7.2 molecules was sharply up-regulated on sDC that migrated toward the T-cell zone. In contrast, upon lipopolysaccharide stimulation, sDC from T. cruzi-infected mice did not migrate toward the T-cell zone nor did they undergo maturation. Finally, white pulp was severely depleted in both CD4(+) and CD8(+) T cells at the peak of infection. Taken together, these results indicate that profound alterations of migration and maturation of sDC and depletion/redistribution of T cells occur during the acute phase of T. cruzi infection and could be part of another strategy to escape immune surveillance and to persist in the host.

Animals↗

PubMed1982

The in vivo effect of a thymic factor (thymostimulin) on immunologic parameters of patients with untreated Hodgkin's disease.

The in vivo effect of a calf thymus extract (thymostimulin, TS) on the E-rosetting capacity, PHA blastogenic response, serum migration inhibitory activity (LIF) and skin reactivity to recall antigens was evaluated in 19 untreated patients with Hodgkin's disease. In patients the mean percentage of peripheral blood lymphocytes forming E-rosettes increased from 47 to 55.7% (P less than or equal to 0.001; normal: 58.9). The mean PHA stimulation index rose with all three concentrations tested but did not reach normal values. Serum LIF was positive in only one patient prior to treatment with a mean LIF for all patients of 0.75 (P less than or equal to 0.005). Skin tests were positive in ten patients (52.6%) prior to therapy and 18 patients following therapy (94.7%; P less than or equal to 0.05). Thymostimulin, in vivo, appears to return immunologic competency to a population of untreated patients with Hodgkin's disease.

Adult↗

PubMed1994

Mechanical evaluation of a canine intervertebral disc spacer: in situ and in vivo studies.

An elastomeric intervertebral disc spacer with hydroxyapatite ingrowth surfaces was implanted in a canine model. We studied (a) the mechanical behavior of motion segments at time 0 and at 3, 6, and 12 months and (b) the effect of the interface between the spacer and vertebral bone on implant stability and bone ingrowth. A polymeric spacer was designed with compressive and torsional properties similar to those of the isolated canine lumbar disc. Implantation of the spacer in canine cadaver motion segments permitted in situ biomechanical evaluation at time 0. An in vivo study permitted continuous neurological monitoring of animals, with evaluation of mechanical behavior, stability, and ingrowth at 3, 6, and 12 months. Mechanical testing of cadaver motion segments with the spacer in situ resulted in decreased compressive and torsional stiffnesses, averaging 25 and 42%, respectively. This decrease was due to a combination of the surgical insult to the annulus and decortication of adjacent vertebral endplates. In the in vivo study, all 12 animals tolerated the surgery well and none had permanent neurological impairment. The measured parameters indicated that behavior of the spacer-motion segment composite appeared to return to normal within 3-6 months. However, despite use of a porous hydroxyapatite on the implant surface, there was no significant bone ingrowth. Instead, a layer of dense fibrous connective tissue was formed at the spacer-vertebral bone interface. Early migration of five of the 12 spacers resulted in eccentric loading patterns with consistent reactive osteophyte formation.

Animals↗

PubMed1996

Strong induction of activin expression after injury suggests an important role of activin in wound repair.

Activins are members of the transforming growth factor beta (TGF beta) superfamily, which comprises a growing group of dimeric proteins. TGF beta and several other members of this superfamily are known to play an important role in wound healing. However, expression of activin during wound healing has not been demonstrated so far. In this study we have analyzed the expression pattern of activin and activin receptors in normal and wounded skin. We found a large induction of activin A and a minor induction of activin B mRNA expression 1 day after skin injury and high expression levels of activin A and B were found within the first 7 days after wounding. At 13 days after injury, expression of activin A mRNA had returned to the basal level, whereas high levels of activin B persisted. In situ hybridization studies revealed expression of activin A in the granulation tissue below the wound and activin B in the hyperproliferative epithelium at the wound edge and in the migrating epithelial tongue. All known types of activin receptors as well as the activin binding protein follistatin were expressed in normal and wounded skin. However, no significant induction of receptor gene expression was seen during the repair process. The distribution of activins and activin receptors in the wound suggests multiple autocrine and paracrine activities of the ligands during wound healing. Our data provide evidence for a novel function of activin and indicate that--besides TGF beta s themselves--other members of this superfamily might also play an important role in tissue repair.

Activin Receptors↗

PubMed1980

Prostaglandin induced shape changes in fibroblasts grown in cell culture.

PGE2 induced shape changes in porcine adventitial fibroblasts grown on glass in low density monolayer cell cultures. Incubation of the cells with PGE2 at concentrations of 100 ng/ml and 1000 ng/ml induced rounding of flat fibroblasts within one hours. The rounded cells had a small rim of cytoplasm around the nucleus and from one to several long thin arborizing cytoplasmic processes extending outward along the substratum. Removal of the PGE2 resulted in transient blebbing of the cell membrane of both the cell body and the processes as the cells returned to their flat normal morphology within one hour. The effect could be inhibited by 1% fetal calf serum. PGF2 alpha did not however induce similar changes. This difference between PGE2 and PGF2 alpha is similar to a report on spreading and migration of mouse peritoneal macrophages, and suggests that under certain conditions PGE2 may have the ability to induce shape changes in cells.

Animals↗

PubMed1988

Internal motions in proteins and gating kinetics of ionic channels.

Single-channel current recordings have revealed a complex kinetic behavior of ionic channels. Many channels exhibit closed-time distributions in which long waiting times occur with a much higher frequency than predicted by a simple exponential decay function. In this paper a model for opening-closing transitions that accounts for internal motions in the protein matrix is discussed. The model is based on the notion that the transition between a conductive and a nonconductive state of the channel represents a local process in the protein, such as the movement of a small segment of a peptide chain or the rotation of a single amino-acid residue. When the blocking group moves into the ion pathway, a structural defect is created consisting in a region of loose packing and/or poor hydrogen bonding. By rearrangements of neighboring groups, the defect may migrate within the protein matrix, carrying out a kind of random walk. Once the defect has moved away from the site where it was formed, a transition back to the open state of the channel is possible only when the defect has returned by chance to the original position. The kinetic properties of this model are analyzed by stochastic simulation of defect diffusion in a small domain of the protein. With a suitable choice of domain size and diffusion rate, the model is found to predict closed-time distributions that agree with experimental observations.

Animals↗

PubMed2003

Increased expression of the ubiquitin-proteasome pathway in murine myotubes by proteolysis-inducing factor (PIF) is associated with activation of the transcription factor NF-kappaB.

Proteolysis-inducing factor (PIF), isolated from a cachexia-inducing murine tumour, has been shown to stimulate protein breakdown in C(2)C(12) myotubes. The effect was attenuated by the specific proteasome inhibitor lactacystin and there was an elevation of proteasome 'chymotrypsin-like' enzyme activity and expression of 20S proteasome alpha-subunits at concentrations of PIF between 2 and 16 nM. Higher concentrations of PIF had no effect. The action of PIF was attenuated by eicosapentaenoic acid (EPA) (50 microM). At a concentration of 4 nM, PIF induced a transient decrease in IkappaBalpha levels after 30 min incubation, while no effect was seen at 20 nM PIF. The level of IkappaBalpha, an NF-kappaB inhibitory protein, returned to normal after 60 min. Depletion of IkappaBalpha from the cytosol was not seen in myotubes pretreated with EPA, suggesting that the NF-kappaB/IkappaB complex was stabilised. At concentrations between 2 and 8 nM, PIF stimulated an increased nuclear migration of NF-kappaB, which was not seen in myotubes pretreated with EPA. The PIF-induced increase in chymotrypsin-like enzyme activity was also attenuated by the NF-kappaB inhibitor peptide SN50, suggesting that NF-kappaB may be involved in the PIF-induced increase in proteasome expression. The results further suggest that EPA may attenuate protein degradation induced by PIF, at least partly, by preventing NF-kappaB accumulation in the nucleus.

Animals↗

PubMed1999

Sacral nerve stimulation for treatment of refractory urinary urge incontinence. Sacral Nerve Stimulation Study Group.

PURPOSE: A prospective, randomized study was performed to evaluate sacral nerve stimulation for the treatment of refractory urinary urge incontinence. MATERIALS AND METHODS: Primary outcome variables were obtained from voiding diaries. After baseline evaluation candidates who satisfied inclusion criteria were enrolled into the study. Test stimulation results determined eligibility for randomization into a stimulation (treatment) or delay (control) group. The stimulation group included 34 patients who underwent implantation and were followed for 6 months. The delay group comprised 42 patients who received standard medical therapy for 6 months and then were offered implantation. The stimulation group completed a therapy evaluation test (on versus off) after 6 months. RESULTS: At 6 months the number of daily incontinence episodes, severity of episodes and absorbent pads or diapers replaced daily due to incontinence were significantly reduced in the stimulation compared to the delay group (all p<0.0001). Of the 34 stimulation group patients 16 (47%) were completely dry and an additional 10 (29%) demonstrated a greater than 50% reduction in incontinence episodes 6 months after implantation. Efficacy appeared to be sustained for 18 months. During the therapy evaluation test the group returned to baseline levels of incontinence when stimulation was inactivated. Urodynamic testing confirmed that sacral nerve stimulation did not adversely affect voiding function. Complications included implantable pulse generator site pain in 15.9% of the patients, implant site pain in 19.1% and lead migration in 7.0%. Surgical revision was required in 32.5% of patients with implants to resolve a complication. There were no reports of permanent injury or nerve damage. CONCLUSIONS: Sacral nerve stimulation is safe and effective in treating refractory urinary urge incontinence.

Adult↗

PubMed2001

[Stomach ache and fever after consumption of watercress in Turkey: fascioliasis].

A 52-year-old woman presented several months after returning from a visit to Turkey with stomach-ache and fever. Laboratory results showed leucocytosis with marked eosinophilia. Furthermore, serum liver enzyme activities were slightly elevated. A CT scan of the abdomen showed several spots which, on a later scan, had migrated. Serologic tests confirmed the clinical diagnosis of fascioliasis. The patient was successfully treated with triclabendazole. Infection presumably occurred after eating watercress which the patient had bought on a market in Turkey.

Abdominal Pain↗

PubMed2002

West Nile virus and the threat to the UK.

West Nile virus (WNV) is an RNA virus and a member of the Flaviviridae family. The recent geographical expansion of WNV into areas where no activity had been previously reported has been highlighted by the detection of WNV in North America. There is also a recent trend for more numerous and serious outbreaks in Eurasia. The main hosts are birds and the principle vectors are mosquitoes, usually of the genus Culex. Although most infected people do not become symptomatic, severe diseases such as encephalitis and, less commonly, aseptic meningitis may occur, more frequently in the elderly. The public can be protected by giving advice on the avoidance of mosquito bites and by the implementation of ecological surveillance and measures to reduce the mosquito population. While a few human cases have been identified in returning travellers, WNV has not been reported in any animal or bird in the UK. However, this may simply indicate that the diagnosis has not been sought. Potential avian hosts and mosquito vectors of WNV are present in the UK and birds migrate to the UK from areas of endemic WNV activity. However, the population density of mosquitoes is relatively low and therefore the risk of WNV being transmitted in the UK is thought to be low. We lack sufficient information on the ecology of the virus, and on mosquito populations, to accurately determine this risk. Clinicians are advised to consider WNV as a differential diagnosis, especially in patients over 50 years old with a clinical picture of viral encephalitis or aseptic meningitis presenting in the summer months.

Animals↗

PubMed1995

The impact of this involuntary mass "return" to Jordan in the wake of the Gulf crisis.

"This article investigates the impact of the involuntary movement to Jordan of about 300,000 Palestinians in the wake of the Gulf crisis of 1990-91. It explores the character of the population that arrived en masse in Jordan and whether their arrival burdened or benefitted that country.... The involuntary migration compounded other effects of the Gulf crisis on Jordan and exacerbated the country's already serious economic problems. Integration of the returnees was painful. But contrary to initial expectations, the mass arrival did not result in unmitigated disaster and may have contributed to an economic recovery in Jordan, suggesting that there may be potentially beneficial windfall effects of sudden population influxes, even when they are involuntary and disorderly."

Acculturation↗

PubMed2004

Minimally invasive treatment of osteoporotic vertebral compression fracture.

BACKGROUND: The use of percutaneous vertebroplasty (PV) to treat osteoporotic vertebral fractures is increasing. This investigation assesses the efficacy and safety of PV for refractory pain owing to osteoporotic vertebral compression fractures. METHODS: A retrospective investigation of PV was conducted with a minimal of 1 year follow up. PV with polymethylmethacrylate (PMMA) was performed on 75 patients with osteoporotic vertebral compression fractures that responded poorly to the conservative therapy. Patients were asked to quantify their degree of pain using Huskisson's visual analogue scale to assess the clinical results. RESULTS: Eighty-seven vertebrae treated using PV in 70 patients were evaluated with a minimal of 1 year follow up. Pain, as assessed on the VAS, decreased from 80+/-16 mm before PV to 36+/-28 mm at 1 month after PV and 30+/-19 mm at the most recent follow up. The reduction in pain from the baseline to 1 month (p=0.031) and to final follow up (p=0.023) were both statistically significant. Sixty-two patients (85.5%) quickly returned to their pre-injury activity level and achieved better quality of life. CONCLUSIONS: PV is effective in pain reduction for painful vertebral compression fractures. It provided significant pain relief. Skillful techniques and careful safeguards can minimize the risks of PMMA migration.

Aged↗

PubMed1987

Schwann cell proliferation and migration during paranodal demyelination.

This study examined Schwann cell behavior during paranodal demyelination induced by beta,beta'-iminodipropionitrile (IDPN). The stimuli for Schwann cell proliferation, extensively studied in vitro, are less well understood in vivo. Most in vivo systems previously used to examine Schwann cell proliferation in disease are dominated by loss of internodal myelin sheaths. As used in this study, IDPN administration produces neurofilamentous axonal swellings and paranodal demyelination, without segmental demyelination or fiber degeneration. We asked whether Schwann cells would proliferate following the restricted paranodal demyelination that accompanies the axonal swellings, and if so what the sources and distributions of new Schwann cells might be. IDPN was given as a single large dose (2 ml/kg) to 21-d-old rats. Neurofilamentous axonal swellings formed in the proximal regions of motor axons, reaching their greatest enlargement in the root exit zone 8 d after IDPN administration. These swellings subsequently migrated distally down the nerves at rates approaching 1 mm/d. The axonal enlargement was consistently associated with displacement of the myelin sheath attachment sites into internodal regions, and consequent paranodal demyelination. This stage was associated with perikaryal changes, including nucleolar enlargement, "girdling" of the perikaryon, and formation of attenuated stalks separating the perinuclear region from the external cytoplasmic collar. Schwann cells proliferated abundantly during this stage. Daughter Schwann cells migrated within the endoneurial space (outside the nerve fiber basal laminae) to overlie the demyelinated paranodes of swollen nerve fibers. In these regions, local proliferation of Schwann cells continued, resulting in large paranodal clusters of Schwann cells. As the axonal calibers subsequently returned to normal, the outermost myelin lamellae of the original internodes returned to their paranodal attachment sites and the supernumerary Schwann cells disappeared. Formation of short internodes, segmental demyelination, and nerve fiber loss were rare phenomena. These results indicate that paranodal demyelination is a sufficient stimulus to excite abundant Schwann cell proliferation; neither internodal demyelination nor myelin breakdown is a necessary stimulus for mitosis. The 3H-thymidine incorporation studies indicated that the sources of new Schwann cells included markedly increased division of the Schwann cells of unmyelinated fibers and, as they formed, supernumerary Schwann cells. In addition, there were rare examples of 3H-thymidine incorporation by Schwann cells associated with myelinated nerve fibers.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed2000

Selective expression of neural cell adhesion molecule (NCAM)-180 in optic nerve head astrocytes exposed to elevated hydrostatic pressure in vitro.

Glaucomatous optic neuropathy is usually associated with elevated intraocular pressure. Optic nerve head astrocytes may respond to intraocular pressure by stimulation of pressure-sensitive mechanoreceptors on the cell surface. Neural cell adhesion molecule (NCAM) a transmembrane protein, mediates cell adhesion and migration. The NCAM 180 isoform increases in astrocytes of glaucomatous optic nerve head. We characterized the relative expression of NCAM isoforms in human optic nerve head astrocytes grown under elevated hydrostatic pressure. Astrocytes cultured from normal human optic nerve heads were exposed to either atmospheric or continuous hydrostatic pressure of 60 mm Hg, and analyzed at 6-48 h. Changes in cell shape, immunoreactivity, and distribution of GFAP, actin and NCAM were observed in pressure-treated cultures. Newly synthesized (35)S-labeled NCAM protein immunoprecipitated from cell lysates was increased 2-fold within 24 h after exposure to elevated pressure compared to control. The increase in NCAM synthesis was primarily due to the NCAM 180 isoform. A significant increase in NCAM 180 mRNA levels was detected by RT-PCR and Northern blots in cultured optic nerve head astrocytes within 6 h after exposure to elevated pressure. NCAM 180 mRNA and protein synthesis decreased after 24 h and returned to control levels by 48 h. Our data indicate that NCAM 180 transcription and synthesis in astrocytes is stimulated by elevated hydrostatic pressure. Because NCAM 180 interacts with the cytoskeleton through an extended cytoplasmic tail, a selective and transient increase in NCAM 180 in optic nerve head astrocytes exposed to elevated pressure may be relevant to the migration and interactions of reactive astrocytes in glaucoma.

Adolescent↗

PubMed1991

Importance of migrants infected with Onchocerca volvulus in west African river valleys protected by 14 to 15 years of Simulium control.

A study was done to determine the importance of human migration from non-controlled endemic onchocerciasis foci to the river valleys that have been protected for the past 14 to 15 years by the vector control operations of the Onchocerciasis Control Programme in West Africa. The aim of the study was to assess the contribution of migrants to the prevalence and intensity of infection in villages from 5 major river valleys and their potential role in causing relapse of transmission once the vector is allowed to return. In Burkina Faso the migrant population varied from 0.0% to 18.1% of the village population, and averaged 4.9%. Migrants accounted only for 0.6% of the population in Ghanaian and Ivorian villages along the Black Volta river. The prevalence of infection was significantly higher in migrants (8.2%) than in non migrants (1.1%) in the surveyed villages in Burkina Faso, and 1.5% of migrants had infections with more than 16 microfilariae per snip as against 0.2% of non migrants. Nearly all infected migrants came from the south of the Côte d'Ivoire. The study shows that human migration has caused the importation of Onchocerca volvulus from non-controlled areas. However, the epidemiological importance of this phenomenon is limited because of the very small number of infected migrants per village while two-third of the infected migrants are believed to be infected with the less pathogenic forest strain of the parasite. Because migration patterns changes geographically and over time similar studies will be continued on a regular basis.

Animals↗

PubMed1993

Myoelectric motility patterns following open versus laparoscopic cholecystectomy.

Laparoscopic surgery is associated with a lack of postoperative ileus. To determine if differences exist in postoperative motility patterns, 8 dogs were instrumented with bipolar electrodes 10-14 days prior to open (n = 4) or laparoscopic (n = 4) cholecystectomy. In both groups, Phase II activity disappeared in the first 24 h after operation. The appearance of the migrating myoelectric complex in the small intestine and the migrating colonic complex were used as criteria for recovery from postoperative ileus. Postoperative migrating myoelectric complex cycle length, migrating myoelectric complex, migration velocity, and colonic spike bursts/hour were also measured. No statistically significant differences were observed between groups in study parameters examined. Postoperative myoelectric motility patterns in dogs undergoing open versus laparoscopic cholecystectomy are not different. Other factors may be responsible for the rapid return to oral intake following laparoscopic cholecystectomy.

Animals↗