Effect of time of admission on compliance with deep vein thrombosis prophylaxis in a tertiary medical intensive care unit

OBJECTIVE

We sought to evaluate deep vein thrombosis (DVT) prophylaxis compliance according to time of admission in a medical intensive care unit (MICU).

METHODS

This was a retrospective cohort study at a closed tertiary MICU. We classified patients into three groups (week days, weekends, and week nights), according to time of admission. An unweighted risk factor score (RFS) was calculated from 20 known risk factors. We defined DVT prophylaxis compliance as any type of prophylaxis (mechanical or pharmacologic) for RFS 3. Non-compliance was defined as no prophylaxis or single-type prophylaxis for RFS > 3.

RESULTS

We analyzed 105 admissions. Eighty (76.19%) patients received compliant DVT prophylaxis, and 25 (23.81%) patients received non-compliant regimens of whom 11 (10.48%) were not on any prophylaxis. DVT prophylaxis compliance was not different across the three admission groups. The non-compliant DVT prophylaxis group had a higher RFS (3.48 +/- 2.1 vs. 2.25 +/- 1.5; P = 0.011), a trend towards fewer female patients (40% vs. 60%; P = 0.079), and a higher percentage of admissions by interns at the first postgraduate year (PGY) level (28% vs. 5.4%; P = 0.01). Logistic regression revealed that only RFS and PGY level were independent predictors for compliance (P = 0.015 and 0.005 respectively). Time of admission was not a significant factor.

CONCLUSIONS

Time of admission did not influence DVT prophylaxis compliance. Compliance improved with higher PGY level and lower RFS. A higher level of knowledge probably explains the association with PGY level; however, we cannot explain the inverse relationship between RFS and compliance.

Use of DNA repair pathway analysis to predict overall survival in head and neck cancer patients treated with TFHX chemoradiotherapy

6033

Background: Concurrent chemoradiotherapy is a standard-of-care for head and neck cancer. Radiotherapy and chemotherapeutic agents damage DNA; lack of adequate repair induces tumor cell death. The network of DNA repair pathways was examined to predict TFHX chemoradiotherapy outcomes. Methods: Biopsy specimens (paraffin) from 60 HNC patients were evaluated from tissue microarrays. Samples originated from patient groups from phase I/II studies: 1) poor-prognosis radiation-naïve, 2) re-irradiation. All were treated with TFHX-based chemoradiotherapy. DNA repair biomarkers XPF, pMK2, PAR, pH2AX, FANCD2, ATM, BRCA1, RAD51, ERCC1 (clone 8F1), and p53 were explored using IHC, automated image processing, and machine reading (>500 cells/read), for nuclear and cytoplasmic quantity, area, and intensity, and correlated with clinical outcome. Results: There was low inter-core variability per tumor with median patient ranking signal to noise ratio of 15.0 across all markers. Patients were stratified into short and long survival groups by determination of critical marker thresholds. Five DNA repair biomarkers (RAD51, ATM, BRCA1, XPF, FANCD2) exhibited univariate significance for overall survival (p = 2.65e-3, 1.53e-2, 4.77e-4, 8.57e-5, 1.32e-3)(additional clinical parameters multivariate analysis was not feasible due to sample size). ERCC1 was not statistically significant (p = 1.0). Pairwise biomarker combinations improved survival group discrimination. Combination of 4 DNA repair biomarkers (FANCD2, BRCA1, ATM, XPF) was also significant (p = 1.31e-4). Discriminant analysis demonstrated higher fractions of correctly identified patients in good/poor survival groups from four-marker tests. Conclusions: Five DNA repair biomarkers predicted overall survival following TFHX-based chemoradiotherapy. By contrast ERCC1 (8F1) was not significant. Combination of markers improved predictive ability in this study. The analysis of DNA repair pathways, particularly in homologous recombination, DNA damage response, and nucleotide excision repair, may be clinically useful. Validation in a larger, homogeneous patient population, and using platinum-based chemoradiotherapy, is indicated and currently ongoing.

[Table: see text]

Locus of control, perceived parenting style, and symptoms of anxiety and depression in children with Tourette's syndrome

AIM

This study explored the contribution of two psychosocial factors, locus of control (LOC) and perceived parenting style, to symptoms of internalizing disorders in children with Tourette syndrome (TS). This contribution was further evaluated in relation to TS severity.

METHODS

Sixty-five children (53 boys, 12 girls) ages 9.0-16.9 years, of normal intelligence, completed questionnaires evaluating their depression and anxiety symptoms, LOC, and maternal parenting style. Their mothers rated TS severity, determined by tic severity, symptoms of attention-deficit hyperactivity disorder (ADHD) and obsessive compulsive symptoms (OCS).

RESULTS

Higher rates of symptoms of anxiety and depression were associated with a more external LOC and a more rejecting and controlling parenting style. Additionally, depression correlated significantly with tic severity, ADHD and OCS, whereas anxiety correlated only with ADHD symptoms and OCS, but not with tics. Regression analyses showed that LOC, OCS and ADHD symptoms each significantly contributed to predicting anxiety level, whereas LOC and ADHD symptoms significantly contributed to predicting depression symptoms.

CONCLUSIONS

Rates of symptoms of anxiety and depression in children with TS are markedly influenced by psychosocial factors, extending beyond the influence of ADHD and OCD, both common comorbid disorders in TS. An internal LOC, which is associated with an accepting and autonomy-granting parenting style, appears to be a protective factor against anxiety and depression.

Fermi edge polaritons in a microcavity containing a high density two-dimensional electron gas

Sharp, near band gap lines are observed in the reflection and photoluminescence spectra of GaAs/AlGaAs structures consisting of a modulation doped quantum well (MDQW) that contains a high density two-dimensional electron gas (2DEG) and is embedded in a microcavity (MC). The energy dependence of these lines on the MC-confined photon energy shows level anticrossings and Rabi splittings very similar to those observed in systems of undoped QW's embedded in a MC. The spectra are analyzed by calculating the optical susceptibility of the MDQW in the near band gap spectral range and using it within the transfer matrix method. The calculated reflection spectra indicate that the sharp spectral lines are due to k{ parallel}=0 cavity polaritons that are composed of e-h pair excitations just above the 2DEG Fermi edge and are strongly coupled to the MC-confined photons.

Lung separation in the patient with a difficult airway

During video-assisted thoracoscopy the lungs should be well collapsed to allow the surgeon an optimal view of the surgical field. The use of 'difficult tubes' such as the double lumen tube or Univent cannot be avoided despite the presence of a difficult airway. If it is only possible to place a single lumen tube, a tube exchanger can be used to switch to a double lumen tube or a Univent tube. Alternatively, a Fogarty embolectomy catheter can be passed down the single lumen tube as an independant bronchial blocker. The Bullard and the Wu laryngoscopes and the laryngeal airway mask can further assist in establishing an airway. Finally, depending on the extent and the length of the procedure, an airway, initially not classified as difficult, may become difficult and postoperative planning is a must.

Video-assisted thoracoscopic surgery

Video-assisted thoracoscopic surgery is finding an ever-increasing role in the diagnosis and treatment of a wide range of thoracic disorders that previously required sternotomy or open thoracotomy. The potential advantages of video-assisted thoracoscopic surgery include less postoperative pain, fewer operative complications, shortened hospital stay and reduced costs. The following review examines the surgical and anesthetic considerations of video-assisted thoracoscopic surgery, with an emphasis on recently published articles.

Angiogenic gene therapy in patients with nonrevascularizable ischemic heart disease: a phase 2 randomized, controlled trial of AdVEGF121 (AdVEGF121) versus maximum medical treatment

The demonstration that angiogenic growth factors can stimulate new blood vessel growth and restore perfusion in animal models of myocardial ischemia has led to the development of strategies designed for the local production of angiogenic growth factors in patients who are not candidates for conventional revascularization. The results of recent clinical trials of proangiogenesis gene therapy have been disappointing; however, significant limitations in experimental design, in particular in gene transfer strategies, preclude drawing definitive conclusions. In the REVASC study cardiac gene transfer was optimized by direct intramyocardial delivery of a replication-deficient adenovirus-containing vascular endothelial growth factor (AdVEGF121, 4 x 10(10) particle units (p.u.)). Sixty-seven patients with severe angina due to coronary artery disease and no conventional options for revascularization were randomized to AdVEGF121 gene transfer via mini-thoracotomy or continuation of maximal medical treatment. Exercise time to 1 mm ST-segment depression, the predefined primary end-point analysis, was significantly increased in the AdVEGF121 group compared to control at 26 weeks (P=0.026), but not at 12 weeks. As well, total exercise duration and time to moderate angina at weeks 12 and 26, and in angina symptoms as measured by the Canadian Cardiovascular Society Angina Class and Seattle Angina Questionnaire were all improved by VEGF gene transfer (all P-values at 12 and 26 weeks < or =0.001). However, if anything the results of nuclear perfusion imaging favored the control group, although the AdVEGF121 group achieved higher workloads. Overall there was no significant difference in adverse events between the two groups, despite the fact that procedure-related events were seen only in the thoracotomy group. Therefore, administration of AdVEGF121 by direct intramyocardial injections resulted in objective improvement in exercise-induced ischemia in patients with refractory ischemic heart disease.

Bevacizumab in unresectable hepatocellular carcinoma (HCC) for patients without metastasis and without invasion of the portal vein

4144

Background: HCC is a vascular tumor in which angiogenesis contributes to pathogenesis. VEGF-inhibition has not been previously attempted in cirrhosis or HCC. Methods: We enrolled patients with unresectable HCC to treatment with bevacizumab at 5 mg/kg or 10 mg/kg every 14 days to assess safety and preliminary efficacy. Inclusion criteria were BR < 3.0 mg/dl, transaminases 75K and PT within 4 seconds of normal. Additional criteria included no history of myocardial infarction, stroke, or condition requiring ongoing antiplatelet or antithrombotic therapy. Results: Initial safety assessments for patients treated for at least 8 weeks indicate that 10 of 11 patients treated at 5 mg/kg and 7 of 8 patients treated at 10mg/kg tolerated therapy with acceptable toxicity. Of the first 28 patients treated at either dose, four have had therapy discontinued because of adverse events (including one grade 3 transient ischemic attack). Three patients had serious esophageal bleeding which was likely secondary to progression of HCC and liver disease (although contribution of drug to these events cannot be excluded). The protocol has been modified to identify and treat esophageal varices prior to enrollment. Other toxicities have included grade 2 fatigue, abdominal pain, gastric ulcer, hypertension, hyperbilirubinemia, rash and proteinuria and grade 1 gingivitis, diarrhea, vomiting and epistaxis. Of the initial 25 patients evaluable for efficacy, 5 had progressive disease within 16 weeks. Two patients had PR and 18 had SD. Median time-to-progression was 6.5 months (range 3.9–24.2). Nineteen of 25 (76%) patients had HCC that progressed following transplant, surgery, RFA or embolization procedures. Conclusions: Bevacizumab can be given safely at both 5 mg/kg and 10 mg/kg in HCC patients with localized, unresectable HCC, preserved liver function and no significant esophageal varices. Preliminary results suggest significant disease-modifying effect (80% disease-control rate); median time-to-progression to-date has exceeded 6-months.

[Table: see text]

Modulation of integrin α5 in head and neck cancer cells by epidermal growth factor and its contribution to the malignant phenotype

15512

Background: The primary therapy for head and neck cancer consists of combination treatment with radiation and chemotherapy. While this combined modality approach is often curative, a significant fraction of patients have residual viable tumor cells after treatment that can result in progressive disease or relapse. We hypothesize that a significant contribution of cell survival results from interaction of cancer cells with the tumor microenvironment that includes soluble ligands of growth factor receptors and structural ligands of cell surface adhesion molecules. One of the growth factors with reported tumor survival effects is epidermal growth factor (EGF). We investigated the contribution of EGF to the relationship of 1483 head and neck cancer cells with their microenvironment. Methods: We treated 1483 head and neck cancer cells with variable concentrations of EGF from 0.1 to 20 nM and carried out western blots and flow cytometry to determine the expression of relevant integrins. Effects of interventions were evaluated by soft agar colony assays, proliferation and survival in tissue culture and adhesion to culture plates coated with integrin ligands. Results: Western blots demonstrated an EGF-induced increase in the expression of intgerin α5 but no change in the expression of integrins α2 or β1. The presence of dissolved fibronectin, a ligand of integrin α5β1, but not of collagen I, a ligand of integrin α2β1, provided a survival advantage to colonies in soft agar in EGF-treated cells. Experiments are determining whether this survival advantage translates to a shift in the dose-response curve to paclitaxel and ionizing radiation, on activation of caspases 3 and 8 and cleavage of poly (ADP- ribose) polymerase (PARP). These data are being correlated with EGF-induced modulation of adhesion to fibronectin, collagen and control plates. We have constructed adenoviral vectors expressing short hairpin RNA (shRNA) sequences to integrins α5 and α2 to confirm the role of integrin α5 expression in the EGF-induced modulation of survival. Conclusions: These data support a potential contribution to survival of head and neck cancer cells by modulation of integrins by EGF through interaction with their ligands in the microenvironment.

No significant financial relationships to disclose.

Evaluation of the profile of thrombin generation during the process of whole blood clotting as assessed by thrombelastography

The objective of this study was to evaluate the possibility of linking the tracing of whole blood clotting in a thrombelastograph (TEG) hemostasis system with the generation of thrombin assessed by thrombin/antithrombin complex (TAT). Citrated whole blood containing corn trypsin inhibitor from volunteers was clotted in the presence of CaCl2 and tissue factor. Clotting was monitored with the eight channels of a TEG system. At different time points, the whole blood TEG reaction cups were kept in a cold quenching solution, centrifuged, and the supernatants were kept at -80 degrees C until assayed for TAT by ELISA. The total thrombus generation (TTG) was calculated from the first derivative of the TEG waveform and was compared with thrombin generation measured by TAT. The two vector values--the TAT thrombin generation data and the corresponding TEG TTG--were analyzed using Pearson correlation coefficients (r) and linear, non-linear and natural log (ln) transformation of TAT values for least-squares goodness-of-fit curves. The best least-squares fit is an exponential curve. Linearizing using the ln of the TAT thrombin generation variable produces the same r (0.94) as of the exponential curve. The prediction equation is y = 8.0465 + 0.0005x (P < or = 0.0001), where y is the TAT thrombin generation variable in the ln transformation and x is the TEG TTG variable. The high magnitude of r and the high significance of the prediction equation demonstrate the high efficacy of the prediction of TAT thrombin generation by the use of TEG TTG.

Uveitis in children and adolescents

AIMS

To study the relative occurrence of uveitis (intraocular inflammation) and its causes in children and adolescents.

METHODS

Patients with uveitis examined and followed during a period of 10 years were categorised by age and sex. All underwent ocular examination and an individually tailored battery of laboratory tests. The intraocular manifestations were classified according to the anatomical location of the inflammation and their most probable cause. The final diagnosis was based on typical clinical ocular and extraocular symptoms and signs and on the results of specific laboratory investigations.

RESULTS

Out of 821 patients, 276 (33.1%) were 18 years of age or younger with a male to female ratio of 1 to 1. In these 276 children and adolescents, 70.3% had bilateral ocular involvement. Intermediate uveitis was the most frequent anatomical diagnosis. In many cases, symptoms were mild despite the prominent signs and marked decrease of vision. The underlying cause for the uveitis was evaluated as non-infectious in 184 cases (66.7%) and infectious in 92 cases (33.3%). A potential aetiology and/or a definite clinical diagnosis were established in 74.6% of the cases and only 25.4% of the 276 patients were classified as idiopathic. Juvenile idiopathic arthritis (JIA) was the most common systemic disease association diagnosed in 14.9% of these children. Parasite infestation was the most common infectious association.

CONCLUSIONS

Uveitis in children and adolescents is not as low as previously reported. Parasite infestation on the one hand and JIA on the other hand are the most common aetiologies associated with the uveitis in these young patients.

Efficacy of botulinum-A toxin in adults with neurogenic overactive bladder: initial results

INTRODUCTION AND OBJECTIVES

To study the effects of intradetrusor botulinum-A toxin (BTA) (BOTOX) injections in adult patients with detrusor overactivity who failed to respond to anticholinergic medications or developed intolerable side-effects.

MATERIALS AND METHODS

Ten patients (average age 41 years, range 19-76 years) with neurogenic bladder and detrusor overactivity who were using clean intermittent catheterization 4 to 7 times a day with anticholinergic therapy were included in our study. Their history, physical examination, abdominal ultrasound, urine analysis, serum creatinine and electrolytes, as well as multichannel urodynamic evaluation were documented before administration of BTA injections. Anticholinergic medication was stopped at the time of injection. Three hundred to 400 U of BTA were injected into 30 to 40 different sites in the detrusor muscle under cystoscopic guidance. Clinical assessment and urodynamic testing were repeated 3 months after injection.

RESULTS

Five patients were tetraplegic and five were paraplegic at the thoracic or lumbar level. Three patients had incontinence episodes between catheterizations before treatment, and only one patient continued to have incontinence episodes between catheterizations after treatment. Reflex volume increased by 63.08% from 180 +/- 44.99 ml to 293.7 +/- 208.42 ml (p < 0.02). Maximal bladder capacity was augmented by 73.63% from 290 +/- 131.64 ml to 518.20 +/- 273.35 ml (p < 0.03). Maximal detrusor pressure decreased by 15.52% from 69.60 +/- 39.19 cmH(2)O to 58.80 +/- 33.95 cmH(2)O (p < 0.2). No patients complained of side effects.

CONCLUSION

BTA appears to be an effective and safe therapeutic option for overactive bladder in patients with spinal cord injury failing anticholinergic therapy and delays more invasive treatments. These initial results confirm European literature reports.

Effects of coagulation factor deficiency on plasma coagulation kinetics determined via thrombelastography: critical roles of fibrinogen and factors II, VII, X and XII

BACKGROUND

Thrombelastography (TEG) is used to assess coagulopathy. However, a comprehensive characterization of the effects of specific coagulation factor deficiencies and mode of activation on TEG data does not exist.

METHODS

Thrombelastography was performed for 15 min with control plasma and plasmas deficient (<1% activity) in Factors II, V, VII, VIII, IX, X, XI, XII, or XIII activated with celite (0.28 mg ml(-1)) or tissue factor (TF, 0.1%) (n = 6 per condition). Additional fibrinogen concentration activity (75-345 mg dl(-1)) and Factor II, VII, X and XII activity-response relationships (1%, 6.25%, 12.5%, 25%, 50% and 100% activity) were obtained (n = 8 per condition). Thrombelastography parameters included reaction time (R), angle (alpha), and clot strength (A, amplitude; G, elastic modulus).

RESULTS

Celite activation of FXII-deficient plasma, TF activation of FVII-deficient and FX-deficient plasma, and celite or TF activation of FII-deficient plasma resulted in an almost undetectable clot. Compared to control values, celite activation of plasmas deficient in FXI, FIX and FVIII resulted in prolonged R and decreased alpha values, whereas TF activation resulted in decreased alpha values. Celite and TF activation of FV-deficient plasma resulted in prolonged R and decreased alpha values, whereas FXIII-deficient plasma had decreased alpha, A and G-values compared to control values.

CONCLUSIONS

The fundamental finding of this study is that coagulation factor deficiencies affect TEG parameters in both a factor-dependent and activation-dependent fashion. Utilizing both celite and TF activation improves the diagnostic power of TEG. Based on such TEG data, more targeted administration of blood products could potentially help improve perioperative hemostatic outcomes.

Supraspinal and spinal cord opioid receptors are responsible for antinociception following intrathecal morphine injections

BACKGROUND AND OBJECTIVE

The clinical practice of spinal morphine administration for pain relief is based on observations in animals that opioid receptors exist in the spinal cord and intrathecal injections of opioids in those species (mostly rats) lead to antinociceptive effects. Clinicians are well aware that administration of spinal opioids is associated with side-effects, such as nausea and respiratory depression, that indicate supraspinal spread of the drug administered. Those observations call into question how much of the observed pain relief is due to action of the drug in the brain. This study investigated the spinal cord actions of morphine given intrathecally to rats in a model that allows investigation of drug-receptor interaction at the spinal cord level. Experiments were performed on male Wistar rats with chronically implanted lumbar subarachnoid catheters.

METHODS

Nociceptive thresholds were measured in rats given morphine intrathecally alone and in combination with intrathecal injections of selective opioid receptor antagonists: beta-funaltrexamine (mu), naltrindole (delta) and nor-binaltorphimine (kappa).

RESULTS

Intrathecal morphine caused dose-related antinociceptive effects that were reversed totally by naloxone. Intrathecal beta-funaltrexamine and naltrindole did not reverse the effects of intrathecal morphine. However, intrathecal nor-binaltorphimine did reverse the electrical current threshold effects of morphine but not tail flick latency.

CONCLUSIONS

Antinociception following intrathecal morphine involves spinal and supraspinal opioid receptors. The tail flick effect described in rat experiments involves actions at opioid receptors in the brain that override any action that may be caused by combination of morphine with mu-opioid receptors in the spinal cord.

My self as an other: on autoimmunity and "other" paradoxes

The rubric autoimmunity currently encompasses sixty to seventy diverse illnesses which affect many of the tissues of the human body. Western medical practice asserts that the crisis known as autoimmune disease arises when a biological organism compromises its own integrity by misrecognising parts of itself as other than itself and then seeks to eliminate these unrecognised and hence antagonistic aspects of itself. That is, autoimmune illnesses seem to manifest the contradictory and sometimes deadly proposition that the "identity": body/self both is and is not "itself". Based on the assumption that under normal circumstances "the self" ought to coincide naturally with "the body"-or at the very least the self ought to inhabit the living location of the body more or less unproblematically-this scientific paradigm depicts autoimmune illness as a vital paradox. Yet for those of us who have lived through the experience of an autoimmune crisis, the living paradox that we embody may also lead us to question the basis upon which these medical assumptions rest. This essay raises some of these questions.

The sheep as a model for coronary artery bypass surgery

The sheep is considered to be a suitable model for cardiovascular surgery because of its ease of handling, size, and vascular anatomy which bears close resemblance to the human. Several difficulties, however, have limited the use of the sheep for such a purpose-mainly the high infection rate resulting from median sternotomy incision and its susceptibility to intractable ventricular fibrillation (VF) with the slightest manipulation of the heart, and even the risk of short periods of myocardial ischaemia. We have used the sheep model extensively to perform coronary artery bypass surgery and were successful in overcoming these difficulties. Fifty-seven adult female sheep were used to test a new anastomotic device for the creation of a sutureless connection between venous and arterial grafts and the coronary arteries. The study required full access to the heart and great vessels and mobilization of one of the internal mammary arteries. Changing to the left lateral thoracotomy (LLT) approach solved the initial fatal problems of postoperative infected median sternotomy incisions. Aggressive prophylactic treatment with anti-arrhythmic drugs, maintenance of normothermia and myocardial preconditioning rendered the heart much less vulnerable to manipulations and ischaemia. These measures have reduced the mortality rate from 45% to 0% (P <0.0001). With specific operative techniques and pharmaceutical interventions, the sheep can be effectively and safely used as a model for coronary artery surgery.

Surgical treatment of end stage emphysema

Emphysematous changes are common in the general population. A significant number of these patients requires surgical interventions. Lung volume reduction surgery (LVRS) rapidly gained popularity without a sufficient evidence of beneficial outcome; the presumed mechanism of improvement in lung function is secondary to re-expansion of more normal, underlying compressed lung. The NETT study proposed to evaluate effectiveness of medical treatment vs LVRS in patients with severe bilateral emphysema. Complete results of the NETT study are unknown yet, but there are evidences of beneficial effects of LVRS, at least in a short term. The anesthetic management of these patients includes the continuation of the bronchodilator therapy till surgery, the use of steroids and antisialologue. Pain relief must be optimal and mobilization must be early. One lung ventilation is an absolute necessity, achieved with double lumen tube insertion.

Methods of lung separation

During video assisted thoracoscopy (VAT) the lung should be well collapsed. When the separation of the lungs is strictly indicated, use of difficult tube, such as double lumen tube (DLT) or Univent tube cannot be avoided, despite the presence of a difficult airway. If a patient has a recognized difficult airway, awake intubation with fiberoptic bronchoscopy can be attempted with Univent tube, DLT or with single lumen tube (SLT). If failure to provide a lung separation could result in a life-threatening situation, there are 2 possibilities to provide a one lung ventilation (OLV) when a SLT is in place: a tube exchanger can be used to position a DLT or a bronchial blocker (BB) can be directed through the SLT in the bronchus. The most used BB is a Fogarty embolectomy catheter. More recently a new BB has been approved by FDA: the Cohen Flexitip Endobronchial Blocker. The most important feature of the blocker is its flexible soft tip that allows to direct it in the desired bronchus. The blocker contains a lumen that allows suctioning of the lung to facilitate deflation, suctioning of secretion and insufflation of oxygen. In summary, the clinician should be able to master different methods of lung separation and make him/her self familiar with the available devices.

The cationic porphyrin TMPyP4 destabilizes the tetraplex form of the fragile X syndrome expanded sequence d(CGG)n

Fragile X syndrome, the most common cause of inherited mental retardation, is instigated by dynamic expansion of a d(CGG) trinucleotide repeat in the 5'-untranslated region of the first exon of the FMR1 gene, resulting in its silencing. The expanded d(CGG)(n) tract readily folds into hairpin and tetraplex structures which may contribute to the blocking of FMR1 transcription. In this work, we report that the cationic porphyrin 5,10,15,20-tetra(N-methyl-4-pyridyl)porphin (TMPyP4) effectively destabilizes in vitro the G'2 bimolecular tetraplex structure of d(CGG)(n) while it stabilizes the G'2 tetraplex form of the telomeric sequence d(TTAGGG)(2). Similarly to TMPyP4, the hnRNP-related protein CBF-A also destabilizes G'2 tetrahelical d(CGG)(n) while binding and stabilizing tetraplex telomeric DNA. We report that relative to each agent individually, successive incubation of G'2 d(CGG)(n) with TMPyP4 followed by exposure to CBF-A results in a nearly additive extent of disruption of this tetraplex form of the repeat sequence. Our observations open up the prospect of unfolding secondary structures of the expanded FMR1 d(CGG)(n) tract of fragile X cells by their exposure to low molecular size drugs or to proteins such as TMPyP4 or CBF-A.

Pantoea agglomerans as a cause of septic arthritis after palm tree thorn injury; case report and literature review

We report the case of a 14 year old healthy boy, who was admitted six weeks after being injured by a palm tree thorn, with limping caused by pain and swelling in his right knee. An ultrasound examination revealed a foreign body in the posterior lateral aspect of the right knee. Pantoea agglomerans was identified in the synovial fluid. The patient underwent two arthrotomies and was treated with amoxicillin-clavulanate intravenously for three weeks. The postoperative course was uneventful, and joint function returned to normal. A review of the literature between 1953 and 2002 revealed that bacterial growth after plant thorn injuries is reported infrequently. Yet when reported, Pantoea agglomearns is the most common organism found. Therefore, it must be considered and suspected in "aseptic" cases of arthritis, when there is a history of a plant thorn injury. We also emphasise the efficacy of ultrasound examination in these cases to identify the presence and location of a plant thorn.

Electron-polariton scattering in semiconductor microcavities

In semiconductor microcavities, electron-polariton scattering has been proposed as an efficient process that can drive polaritons from the bottleneck region to the ground state, achieving Bose amplification of the optical emission. We present clear experimental observation of this process in a structure that allows control of the electron density and we report substantial enhancement of photoluminescence. We show that this enhancement is more effective at higher temperatures due to the different way that electron scattering processes either broaden or relax polaritons.

[Progression of cerebral venous thromboses. A retrospective study]

OBJECTIVES

The management of patients with presumed cerebral venous thrombosis has been recently modified by magnetic resonance imaging and evidence that the early use of heparin decreases mortality and morbidity. Long term outcome of patients with cerebral venous thrombosis (CVT) has rarely been described. We present the results of a follow-up study.

METHODS

Twenty patients admitted between 1987 and 1999 for CVT were retrospectively studied. Outcome and follow-up were obtained from direct observation or telephone interviews.

RESULTS

There were 16 women and 4 men aged a mean of 39 years (range: 19 to 72). The population was followed-up for a mean of 34 months (range: 12-96). All the patients were initially treated with full-dose heparin. Thirteen of the 20 patients (65%) exhibited no after effects. Seven patients (35%) remained neurologically impaired. The outcome of clinical forms with intracranial hypertension appeared better, but the existence of an initial neurological deficit is of poor prognosis. The small cohort in our series did not permit us to identify other poor prognostic factors. One patient (5%) exhibited subsequent epilepsy. Only one patient (5%) suffered for a second CVT. One patient died from an ovarian neoplasm. No systemic venous thromboembolic relapse was reported. Three patients had non complicated pregnancies.

CONCLUSION

Recurrent CVT and systemic venous thrombo-embolic episodes are rare although heparin treatment was suspended early in more than half of the patients. This would question the indication of long-term antivitamin K, which is clearly indicated in auto-immune diseases but is debatable in cases of thrombophilia.