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Summary: The synthesis and living ring opening metathesis polymerization (ROMP) of diacetate functionalized cyclobutene derivatives cis-3,4-bis(acetyloxymethyl)cyclobutene (2) and trans-3,4-bis(acetyloxymethyl)cyclobutene (3) were investigated with the functional group tolerant initiators (PCy3)2(Cl)2Ru&dbond;CHPh (I) and (SIMes)(PCy3)(Cl)2Ru&dbond;CHPh (II) (SIMes: 1,3-dimesityl-4,5‐dihydroimidazol‐2‐ylidene). The kinetic parameters of the ROMP initiated by the ruthenium alkylidene complexes I and II were determined and correlated to monomer stereochemistry. The cis isomer 2 was found to be more reactive than the trans isomer 3 and to generate functional polymers of narrow molecular weight distribution especially with the classical “first generation Grubbs catalyst” I. Block copolymers containing 2 and cyclooctadiene (COD) or norbornene (NBE) were synthesized. Block copolymer poly(2‐b‐COD) was hydrolyzed and converted to a material with a block bearing hydrophilic alcohol functional groups and hydrophobic block.SEC elution profiles: poly(2) prepolymer and block copolymer poly(2-b-COD).

To compare the efficacy of a single intraarticular corticosteroid injection, a supervised physiotherapy program, a combination of the two, and placebo in the treatment of adhesive capsulitis of the shoulder. Ninety-three subjects with adhesive capsulitis of <1 year's duration were randomized to 1 of 4 treatment groups: group 1, corticosteroid injection (triamcinolone hexacetonide 40 mg) performed under fluoroscopic guidance followed by 12 sessions of supervised physiotherapy; group 2, corticosteroid injection alone; group 3, saline injection followed by supervised physiotherapy; or group 4, saline injection alone (placebo group). All subjects were taught a simple home exercise program. Subjects were reassessed after 6 weeks, 3 months, 6 months, and 1 year. The primary outcome measure was improvement in the Shoulder Pain and Disability Index (SPADI) score. At 6 weeks, the total SPADI scores had improved significantly more in groups 1 and 2 compared with groups 3 and 4 (P = 0.0004). The total range of active and passive motion increased in all groups, with group 1 having significantly greater improvement than the other 3 groups. At 3 months, groups 1 and 2 still showed significantly greater improvement in SPADI scores than group 4. There was no difference between groups 3 and 4 at any of the followup assessments except for greater improvement in the range of shoulder flexion in group 3 at 3 months. At 12 months, all groups had improved to a similar degree with respect to all outcome measures. A single intraarticular injection of corticosteroid administered under fluoroscopy combined with a simple home exercise program is effective in improving shoulder pain and disability in patients with adhesive capsulitis. Adding supervised physiotherapy provides faster improvement in shoulder range of motion. When used alone, supervised physiotherapy is of limited efficacy in the management of adhesive capsulitis.

Latex hypersensitivity is a major cause of anaphylaxis during anaesthesia. Patients with spina bifida, health care or rubber industry workers have been considered at risk for latex sensitization. By analogy, the existence of other at-risk subsets of patients with latex exposure due to frequent surgical procedures has been suggested.The aim of this study was to evaluate the prevalence of latex sensitization in a cohort of adult patients with spinal cord injury and repeated latex exposure.Forty-two adult patients with spinal cord injury were studied and retrospectively compared to a group of 30 children with spina bifida evaluated using a similar protocol.Patients were administered a questionnaire concerning history of latex hypersensitivity, atopy, and surgical procedures. Latex sensitivity was investigated by skin prick-tests and latex-specific IgE assay. The search for atopy was based on in vivo and in vitro tests against a panel of environmental allergens.No chronic spinal cord injured patient had a history of latex allergy. When compared with spina bifida, the number of surgical procedures was not statistically different. Although not significantly different, the prevalence of atopy was higher in spina bifida patients. The high level of latex sensitization in spina bifida patients contrasted sharply with the absence of sensitization observed on both skin and in vitro tests in patients with spinal cord injury (P<0.0001).This study confirms that adult patients with chronic neurologic defects resulting from spinal cord injury exhibit a low risk of latex sensitization. These results suggest that considering adult patients with repeated surgical procedures as a group at risk for latex sensitization because of a high degree of latex exposure should be re-examined.

Background:Histamine is thought to be the main cause of adverse reactions to wines. Objective:The purpose of this study was to test the hypothesis that the level of histamine in wine affects the tolerance to wine in 16 subjects with wine intolerance. Methods:We performed a study to examine the effects of wine histamine content in 16 adults with wine intolerance. Each subject underwent 2 double-blind provocation tests with wine: 1 with a wine poor in histamine (0.4 mg/L), and 1 with a wine rich in histamine (13.8 mg/L). Blood was collected for histamine and methylhistamine RIAs at 0, 10, 30, and 45 minutes after ingestion of the wine. Methylhistamine and methylimidazolacetic acid (gas chromatography and mass spectrometry) were measured in urine 5 hours before and 5 hours after ingestion. Results:No significant differences in the occurrence of adverse reactions were noted after ingestion of either of the wines (McNemar test). At 10 minutes, a significant increase was observed in plasma histamine with histamine-poor wine. No significant changes (Wilcoxon test) were observed in the methylhistamine and methylimidazolacetic acid levels after ingestion of either histamine-poor or histamine-rich wine. Conclusion:This study demonstrates that there is no correlation between the histamine content of wine and wine intolerance. The increase of plasma histamine levels at 10 minutes with histamine-poor wine suggested the role of a histamine-releasing substance. The role of acetaldehyde is discussed. (J Allergy Clin Immunol 2001;107:375-8.)

IgE-dependent basophil activation induced by an allergen elicit the release of LTC4 and the expression of the CD63 membrane marker.

Mechanisms for double-electron capture producing projectile doubly excited states in O6++He and Ne10++He collisions are studied. Emphasis is given to slow collisions with projectile energies of a few keV. At these impact energies the production of configurations nln′l′of nonequivalentelectrons (n′≫n) is dominant. It is shown that the creation of nonequivalent electron states O4+(1s22pn′l′) and Ne8+(3ln′l′) with n′⩾6 originates from dielectronic processes involving electron–electron interaction. After the collision the populated excited states decay either by Auger electron emission or by radiative (photon) emission. Individual contributions to radiative stabilization of the Ne8+(nln′l′) states (n=3–4) are studied in the impact-energy range from 1–150 keV. The relative importance of the different contributions to stabilization changes significantly with varying collision energy. At 1 keV the major contribution is due to the decay of the configurations 3lnl′(n⩾6) created by collisional dielectronic processes.

A cross-hybridizing 2.2-kb EcoRI fragment was cloned from two lytic Streptococcus thermophilus bacteriophages with distinct phenotypes. The DNA fragments, which contained two unidentified open reading frames, differed at only 3 of 2207 nucleotide positions. Partial sequencing of a temperate S. thermophilus phage and of a further lytic phage belonging to a different lyric group isolated 20 years earlier from a different geographical area confirmed this extreme sequence conservation. Hybridization of this phage DNA with bacterial host DNA was not observed. The evolutionary implications of these observations are briefly discussed. Copyright 1994, 1999 Academic Press

The objectives of the present study were to determine if carbonic anhydrase III (CA III) demonstrated a specific association for any particular organelle or structure of the skeletal muscle cell and to quantify the activity and content of this enzyme in different types of skeletal muscle fibers. Ultrastructural localization of CA III in the soleus (SOL), deep vastus lateralis (DVL), and superficial vastus lateralis (SVL), composed of predominantly type I, IIa, and IIb fibers, respectively, was performed using a high-resolution immunocytochemical technique and antibody specific for CA III on ultra-thin sections of skeletal muscle embedded in the water-soluble medium polyvinyl alcohol (PVA). The results indicated a uniform distribution of CA III within the sarcomere. Mitochondria, nuclei, triads, Z-, and M-bands were not specifically labeled. Immunoblotting of washed myofibril preparations did not show any detectable CA III associated with this structure. In addition to quantification of the immunogold labeling, CA III activity and content were assayed in the post-mitochondrial supernatant of the three muscles. In the SOL, these values were found to be 3.6-7.6 times higher than in the DVL. The SVL showed a labeling intensity slightly higher than background level, while the enzyme activity and content were indistinguishable from background levels. We therefore conclude that CA III is randomly distributed in the cytoplasm of the three muscle fiber types and that the relative CA III content and activity in the three muscles studied is SOL greater than DVL greater than SVL approximately equal to 0.

In a survey of chicken coccidia in France during 1994, samples of litter were collected from 41 farms. On 31 of these farms, eimerian oocysts were abundant enough to allow monitoring of their numbers in the litter. Peak total oocyst counts on these farms ranged from 16,200 to 1,254,000/g of litter, but no coccidiosis was observed. The chickens reared without anticoccidial agents in their food (poulets biologiques) produced higher and earlier peak oocyst counts in litter than the chickens given medicated food (poulets labels). The oocysts in litter samples from 22 farms (13 poulet biologique, five poulet label, two standard broiler, one breeder and one layer) of the original 41 were identified. Six of the seven eimerian species known to parasitize chickens were found, using combinations of five methods (oocyst morphology, intestinal lesions, enzyme electrophoresis, growth in embryonating eggs and prepatent time). Multispecific infections predominated (95% of 22 farms), up to six species occurring together. Of farms where oocysts were detected, the percentages with each species were: Eimeria acervulina (100%), E. mitis (82%), E. tenella (77%), E. maxima (73%), E. praecox (45%) and E. brunetti (27%). These appear to be the first definite records of E. mitis and E. praecox for France. Although E. necatrix was not found in this survey, it had recently been detected by other workers in France, so that all seven chicken Eimeria species were known to be contemporaneous.

A specific receptor with high affinity for rat androgen-binding protein (rABP) was identified in isolated adult rat germ cells and in the corresponding plasma membrane-enriched preparations. Binding was reversible and time-dependent, with maximum relative binding after 40 min at 4 °C; it was pH-dependent, with maximum binding at pH 6–8. Unlabelled rABP and human sex steroid-binding protein (hSBP), but not lactotransferrin, serotransferrin, asialofetuin, fetuin or bovine serum albumin, competed with labelled rABP for binding sites on isolated germ cells. Scatchard analysis revealed a single class of binding site with apparent dissociation constant (Kd) values of 0·78±0·04 nmand 0·97 ± 0·05 nmin intact germ cells and plasma membrane preparations respectively. A Kdof 1·72±0·12 nmfor hSBP showed that the receptor binding site was effective for both androgen-carrier molecules. Labelled rABP incubated with solubilized germ cell membrane fractions at pH 7 formed a complex excluded from Superose 6B mini-gels; this complex was not formed at pH 3. The receptor complex was also abolished in the presence of a 100fold excess of either unlabelled rABP or unlabelled hSBP, or in the presence of 20 mmEDTA.These results suggest that the plasma membrane of rat germ cells contains a receptor which selectively binds rABP and hSBP.

Patients with COVID-19 pneumonia have an excess of inflammation and increased concentrations of cytokines including interleukin-1 (IL-1). We aimed to determine whether anakinra, a recombinant human IL-1 receptor antagonist, could improve outcomes in patients in hospital with mild-to-moderate COVID-19 pneumonia.

The use of N-heterocyclic carbene (NHC) as a ligand in the gold(i)-catalyzed cycloisomerization of enyne results in the assembly of a new carbocyclic product.

A number of cationic gold(i) complexes have been synthesized and found to be stabilized by the use of N-heterocyclic carbene ligands. These species are often employed as in situ-generated reactive intermediates in gold catalyzed organic transformations. An isolated, well-defined species was tested in gold-mediated carbene transfer reactions from ethyl diazoacetate.

ObjectiveTo analyse the safety of a multidisciplinary concussion management protocol where a team therapist is involved in return-to-play (RTP) decisions.DesignProspective, pre- post-intervention cohort study over 4 seasons of competitionSettingSchool-based American football program (4 teams; grades 8–12)Participants:672 players x year (11–17 year old) for a total of 27741 athlete-exposure.InterventionA protocol based on the Concussion In Sport Group recommendations was implemented. A computerised neuropsychological (CNP) test was used at baseline and prior to clearance for unrestricted training. For seasons 1–2, the protocol required the team physician to make all RTP decision while defined criteria allowed the team physiotherapist to make the vast majority of the RTP decisions over seasons 3–4.Outcome measuresThe primary outcome was the early recurrence (ER) of concussion symptoms following RTP (defined as during the same season).ResultsA total of 119 concussions were identified (55 and 64 for the first and last 2 seasons, respectively; incidence rate 4, 3: 1000 athlete-exposures). At the time of the first clearance decision, the CNP test contributed to a negative RTP decision in 67% of cases. During seasons 1–2 no ER was observed. During season 3 one injury unrelated to football resulted in one case of ER prior to clearance and, during season 4, one case of ER occurred during the second game, 11 days after clearance.ConclusionsSafe management of concussions was achieved whether the team physician or the team therapist was responsible for the application of the terms of the protocol.Competing interestsPierre FréÉééééémont chair of the Canadian Concussion Collaborative.éÉéééééÉdith Castonguay is the physiotherapist for the football program described in this study.Francesco Pepe-Esposito is Head coach of the football program described in this study.None.

ObjectiveTo analyse the potential ways to reunite the mTBI and concussion constructs in order to harmonise screening, diagnosis and management.DesignNarrative review.SettingIn Quebec, the initial management of concussions sustained in a sport or school-based setting falls under the authority of the Ministry of education and sports whereas the Ministry of health governs the clinical management of mTBI. The recent work of a task force on concussions in Quebec has emphasised the need to achieve a unified understanding and operationalization of the two constructs so that persons affected receive consistent information and care.Main resultsSport and school-based concussion management is generally based on the Concussion In Sport Group definition whereas the Quebec health care system relies on the 5 diagnostic criteria proposed by the WHO task force in 2004. Although the 5 classification criteria of mTBI include normal values, the actual definition requires the presence of one or more abnormal criteria. In a public health care system, such a definition structures access to limited public resources. However unfavourable evolution can occur in the absence of phenomena such as LOC or PTA. Yet these cases represent a potentially serious health condition if proper identification and management is not initiated.ConclusionSo far, sport, education and health care stakeholders in Quebec have agreed that the constructs of concussion and TBI must be revisited and better integrated. This process raises challenges and opportunities in terms of operationalization and management. Studies on prognostic indicators should guide this analysis.ConclusionCompeting interests Pierre Frééémont is chair of the Canadian Concussion Collaborative.None.