Synthesis and characterization of isotactic cis-1,4-poly(3-methyl-1,3-pentadiene)

3-Methyl-1,3-pentadiene has been polymerized with the Al(C₂H₅)₂Cl/Nd(OCOC₇H₁₅)₃/Al[CH₂CH(CH₃)₂]₃ system to crystalline polymers consisting essentially of cis-1,4 units (≥80%). NMR examination has shown that the polymers have an isotactic structure. This conclusion was confirmed by X-ray analyses, which further indicated that cis-1,4 isotactic poly(3-methyl-1,3-pentadiene) exists in polymorphic modifications.     

Sonography after renal biopsy: Assessment of its role in 230 consecutive cases

Among 230 patients undergoing ultrasound (US) guided renal biopsy, 218 had postbiopsy sonography. Clinical records were reviewed to correlate symptoms to US findings. In each case of large hematoma (thickness above 1 cm), all postbiopsy sonographic studies were analyzed to look for findings indicative of unfavorable outcome. A total of 96 subcapsular/perirenal hematomas were found. Large hematomas were observed in 20 patients (20/230=8.7%), seven of these (3%) were severely symptomatic. In the absence of clinical signs of bleeding, no patient had clinical consequences. In the presence of clinical signs of bleeding, serious complications occurred only in patients with large hematomas. US thickness of retroperitoneal hematoma correlated to clinical outcome: whenever measured thickness was less than 2 cm, clinical evolution was very favorable, whereas a thickness above 2 cm was invariably associated to clinical signs of bleeding. In six of seven cases of thickness exceeding 3 cm, severe complications developed. An unfavorable evolution was associated with increasing thickness and an echogenicity inappropriate with respect to the time elapsed since biopsy. Hydroureteronephrosis, peritoneal effusion, and anomalous vascular images were indicators of deterioration. We conclude that sonography is indicated only for symptomatic patients and that the monitoring of both thickness and changing echogenicity of retroperitoneal blood collections supplements clinical follow-up.     

Patient re-training in peritoneal dialysis: why and when it is needed

The aim of this multicenter, quantitative, observational study was to analyze compliance and re-training needs of patients on peritoneal dialysis (PD) through the assessment of patient knowledge (with a Patient Questionnaire; phase 1) and patient behavior (home visit with a Score Card; phase 2). A total of 353 patients from 11 Italian centers participated in the first phase and 191 patients from nine centers in the second phase. Overall, 66% of questions on the Patient Questionnaire were answered correctly. Correct answers were more frequent in females than males, in patients under 55 years of age, and in those with higher education. The lowest rate of correct answers involved questions related to diet and physical activity (67% and 51%, respectively). Data collected during the home visit showed that 25% of patients were partially compliant with their drug therapy. Twenty-three percent of patients were non-compliant with the exchange protocol procedures, with a significant association between compliance and the incidence of peritonitis, and 11% were non-compliant with the exit-site protocol procedures without a statistically significant correlation to peritonitis. By combining the two evaluations, we found that approximately one-third (29%) of patients needed reinforcement of knowledge and ability to correctly perform PD as related to infection control and 27% for the correct use of drugs. Looking at the combined evaluation of infection control and drug use, results showed that 47% of patients needed re-training. This need for re-training was greater for younger patients (less than 55 years old), patients with lower education degree and patients in the early or late phase of PD therapy (less than 18 months or more than 36 months). Gender and degree of autonomy had no effect on the need for re-training.     

Changes in the outcomes of severe trauma patients from 15-year experience in a Western European trauma ICU of Emilia Romagna region (1996–2010). A population cross-sectional survey study

Background

Our experience in trauma center management increased over time and improved with development of better logistics, optimization of structural and technical resources. In addition recent Government policy in safety regulations for road traffic accident (RTA) prevention, such compulsory helmet use (2000) and seatbelt restraint (2003) were issued with aim of decreasing mortality rate for trauma.

Introduction

The evaluation of their influence on mortality during the last 15 years can lead to further improvements.

Methods

In our level I trauma center, 60,247 trauma admissions have been recorded between 1996 and 2010, with 2183 deaths (overall mortality 3.6 %). A total of 2,935 trauma patients with ISS >16 have been admitted to Trauma ICU and recorded in a prospectively collected database (1996–2010). Blunt trauma occurred in 97.1 % of the cases, whilst only 2.5 % were penetrating. A retrospective review of the outcomes was carried out, including mortality, cause of death, morbidity and length of stay (LOS) in the intensive care unit (ICU), with stratification of the outcome changes through the years. Age, sex, mechanism, glasgow coma scale (GCS), systolic blood pressure (SBP), respiratory rate (RR), revised trauma score (RTS), injury severity score (ISS), pH, base excess (BE), as well as therapeutic interventions (i.e., angioembolization and number of blood units transfused in the first 24 h), were included in univariate and multivariate analyses by logistic regression of mortality predictive value.

Results

Overall mortality through the whole period was 17.2 %, and major respiratory morbidity in the ICU was 23.3 %. A significant increase of trauma admissions has been observed (before and after 2001, p?<?0.01). Mean GCS (10.2) increased during the period (test trend p?<?0.05). Mean age, ISS (24.83) and mechanism did not change significantly, whereas mortality rate decreased showing two marked drops, from 25.8 % in 1996, to 18.3 % in 2000 and again down to 10.3 % in 2004 (test trend p?<?0.01). Traumatic brain injury (TBI) accounted for 58.4 % of the causes of death; hemorrhagic shock was the death cause in 28.4 % and multiple organ failure (MOF)/sepsis in 13.2 % of the patients. However, the distribution of causes of death changed during the period showing a reduction of TBI-related and increase of MOF/sepsis (CTR test trend p?<?0.05). Significant predictors of mortality in the whole group were year of admission (p?<?0.05), age, hemorrhagic shock and SBP at admission, ISS and GCS, pH and BE (all p?<?0.01). In the subgroup of patients that underwent emergency surgery, the same factors confirmed their prognostic value and remained significant as well as the adjunctive parameter of total amount of blood units transfused (p?<?0.05). Surgical time (mean 71 min) showed a significant trend towards reduction but did not show significant association with mortality (p?=?0.06).

Conclusion

Mortality of severe trauma decreased significantly during the last 15 years as well as mean GCS improved whereas mean ISS remained stable. The new safety regulations positively influenced incidence and severity of TBI and seemed to improve the outcomes. ISS seems to be a better predictor of outcome than RTS.     

Recognition of iodixanol by dendritic cells increases the cellular response in delayed allergic reactions to contrast media

Background Delayed reactions to iodine contrast media (CM) account for 1–3% of patients with adverse reactions to iodine CM. The cellular and molecular mechanisms of these reactions remain poorly documented. Although most of these reactions are T cell mediated, the involvement of dendritic cells (DC) has not been investigated sufficiently. Objective To determine whether the T cell response to iodixanol requires DC as antigen‐presenting cell and, more particularly, to evaluate the changes induced by iodixanol on DC maturation and in vitro production of cytokines after drug stimulation in patients with maculopapular exanthema. Methods Peripheral blood lymphocytes, immature monocyte‐derived DC (imDC) and skin biopsies were obtained from patients with delayed reactions to iodixanol and tolerant subjects. We studied the consequences of the interaction between DC, lymphocytes and iodixanol by phenotype analysis, proliferation and cytokine production. Results A T‐cell‐mediated reaction was evidenced in patient biopsies, with a lymphocyte‐rich, peri‐vascular infiltrate. Iodixanol induced maturation of imDC from patients but not from controls, with expression of the co‐stimulatory markers CD83, CD86 and CD40 and an increase in mean fluorescence intensity of CD80, CD86 and HLA‐DR. In the absence of DC, positive cell proliferation to iodixanol was detected in only one patient while the addition of DC produced a positive test in five of the six patients. Similarly, the increase in cytokines (IFN‐γ, IL‐2, IL‐6, IL‐1b and TNF‐α) was higher when imDC were introduced into the culture together with the culprit drug. Conclusion and Clinical Relevance These results provide evidence for a DC‐mediated mechanism in delayed allergic reactions to CM, influencing T cell proliferation and cytokine production. These new insights will be helpful for designing immunotherapeutic strategies and in vitro diagnostic tests of CM‐delayed reactions. Cite this as: C. Antunez, A. Barbaud, E. Gomez, S. Audonnet, S. Lopez, R.‐M. Guéant‐Rodriguez, I. Aimone‐ Gastin, F. Gomez, M. Blanca and J.‐L. Guéant, Clinical & Experimental Allergy, 2011 (41) 657–664.     

Early-Onset Ventilator-Associated Pneumonia in Severe Traumatic Brain Injury: is There a Relationship with Prehospital Airway Management?

BackgroundPrehospital airway management in severe traumatic brain injury (TBI) is widely recommended by international guidelines for the management of trauma. Early-onset ventilator-associated pneumonia (EOVAP) is a common occurrence in this population and can worsen mortality and functional outcome.ObjectivesIn this retrospective observational study, we aimed to evaluate the association between different prehospital airway management variables and the occurrence of EOVAP. Secondarily we evaluated the correlation between EOVAP and mortality and neurological outcome.MethodsThe study retrospectively evaluated 223 patients admitted from 2010 to 2017 in our trauma intensive care unit for severe TBI. The population was divided into three groups on the basis of the airway management technique adopted (bag mask ventilation, laryngeal tube, orotracheal intubation). Uni- and multivariate logistic regression analyses were performed using the occurrence of EOVAP as the dependent variable, to investigate potential associations with prehospital airway management.ResultsA total of 131 episodes (58.7%) of EOVAP were registered in the study population (223 patients). Laryngeal tube and orotracheal intubation were used in patients with significantly lower Glasgow Coma Scale score on scene and a higher Face Abbreviated Injury Scale; advanced airway management significantly increased the total rescue time. The prehospital airway management technique adopted, prehospital type of sedation or use of muscle relaxants, type of transport, and rescue times were not associated with the occurrence of EOVAP.ConclusionsPrehospital airway management does not have a significant impact on the occurrence of EOVAP in severe TBI patients. Similarly, it does not have a significant impact on mortality or long-term neurological outcome despite increasing duration of mechanical ventilation, intensive care unit, and hospital stay.     

Spinal monoamine mediation of stimulation-produced antinociception from the lateral hypothalamus

Stimulation-produced antinociception can be evoked from a wide variety of sites in the brain, including the lateral hypothalamus (LH). The present study, in rats lightly anesthetized with pentobarbital, examined descending inhibition of the nociceptive tail flick (TF) reflex produced by focal electrical stimulation in the LH and the neurotransmitter(s), at the level of the lumbar enlargement, mediating the inhibition. Systematic tracking studies demonstrated that stimulation in the diencephalon dorsal to the hypothalamus did not reliably inhibit the TF reflex. Inhibition of the TF reflex was produced, however, throughout the hypothalamus at intensities of stimulation typically between 50 and 200 μA. The area requiring low intensities of stimulation (50–100 μA) to inhibit the TF reflex was a diffuse region of the LH, inferior to the mammillothalamic tract and internal capsule, medial to the supraoptic decussation and including the medial forebrain bundle. Microinjections of S-glutamate (100 mM, 0.5μl) in the LH did not inhibit the TF reflex, suggesting that activation of fibers of passage by stimulation was responsible for inhibition of the TF reflex produced from the LH. The intrathecal administration of pharmacologic antagonists (15–30 μg; naloxone, methysergide, phentolamine, prazosin or yohimbine) revealed that the α-adrenoceptor antagonists phentolamine and yohimbine produced the greatest increases in stimulation thresholds in the LH for inhibition of the TF reflex (83.7% and 89.8%, respectively). The intrathecal administration of methysergide produced a lesser, but statistically significant 11% increase in the stimulation threshold for inhibition of the TF reflex. These results indicate that spinal α₂-adrenoceptors primarily mediate the descending inhibition of the TF reflex produced by electrical stimulation in the LH.