NMR signal enhancement of >50 000 times in fast dissolution dynamic nuclear polarization

A novel mixed biradical polarizing agent (BDPAesterTEMPO) showing one of the largest NMR signal enhancements to be observed so far in fast dissolution Dynamic Nuclear Polarization (dDNP).

Paramagnetic spherical nanoparticles by the self-assembly of persistent trityl radicals

The self-association of a water-soluble persistent trityl radical gives rise to paramagnetic nanoparticles: a new class of non-metallic high spin systems.

Self-assembled trityl radical capsules – implications for dynamic nuclear polarization

The OX63 radical forms supramolecular capsules hosting tetraalkylammonium cations. Extensive self-association is also observed under standard dynamic nuclear polarization conditions.

A low-cost, sustainable, second generation system for surveillance of people living with HIV in Spain: 10-year trends in behavioural and clinical indicators, 2002 to 2011

A second-generation surveillance system of people infected with human immunodeficiency virus (HIV) has been implemented in Spain. Behavioural and clinical data were collected between 2002 and 2011 through an annual one-day, cross-sectional survey in public hospitals, including all in- and outpatients receiving HIVrelated care on the survey day. Mean age increased over time (from 38.7 years in 2002 to 43.8 years in 2011) and 68.4% of the 7,205 subjects were male. The proportion of migrants increased from 6.1% to 15.9%, while people who inject or used to inject drugs (PWID and Ex-PWID) decreased and men who have sex with men (MSM) and heterosexuals increased. Unprotected intercourse at last sex increased among MSM and PWID/Ex-PWID. Patients receiving antiretroviral treatment increased significantly from 76.0% to 88.2% as did those with CD4 T-cell counts ≥350 (from 48.2% to 66.9%) and viral copies <200 (from 47.0% to 85.2%). HIV-infected people with hepatitis C virus RNA decreased from 36.0% in 2004 to 29.9% in 2011, while those with HBsAg remained stable at around 4.4%. Implementation of a low-cost, sustainable system for second-generation surveillance in people living with HIV is feasible. In Spain, the information obtained has helped to define and refine public health policy and document treatment effectiveness.

The 13C solid DNP mechanisms with perchlorotriphenylmethyl radicals – the role of 35,37Cl

Chlorinated trityl radicals generate ¹³C DNP frequency sweeps that indicate contributions of e → ^36,37Cl → ¹³C polarization transfer mechanism at low temperatures and that the relative contributions of the solid effect and cross effects mechanism can be controlled by the microwave irradiation power.

Study of hyperglycemia in non critically-ill patients receiving parenteral nutrition: incidence and risk factors

BACKGROUND

The objectives of our study on non-critically ill patients receiving parenteral nutrition (PN) are to assess the incidence of hyperglycemia, the risk factors associated to its development and its influence in patient's evolution.

METHODS

A multicentric prospective observational study was performed in 9 hospitals. Four multivariate studies were developed to study the temporal risk in the occurrence of hyperglycemia (endpoint), intensive care unit (ICU) admission, length of stay (LOS) and death. Demographics, nutrients, drugs and clinical variables were collected. Independent variables studied as a possible risk factors were: sex, diabetes mellitus 2, baseline glycemia, albuminemia, pancreatitis, surgery in the 7 days prior to the end point, infection, insulin/somatostatin/corticoids administration during the study, glomerular filtration rate (GFR), and difference in the amount of glucose administration between the endpoint and one day before.

RESULTS

119 patients were enrolled in the study, 25 cases of hyperglycemia were detected. In the clinical factors associated with PN hyperglycemia, significant variables were: surgery in the 7 days before the end point, GFR, glucose load in the 24 hours previous to the end point insulin administration and somatostatine/octreotide administration during the study. Hyperglycemia was significantly associated with ICU admission and increased LOS.

CONCLUSIONS

Glucose administration in non-critically ill patients receiving PN should be reassessed downwards, especially in the immediate postsurgery, renal impairment and in patients treated with somatostatin analogues. It should be taken into account that an increase in glucose dose may lead to hyperglycemia in these patients and hyperglycemia correlates with longer hospital stay and increased frequency of ICU admissions.

Long-lived states in an intrinsically disordered protein domain

Long-lived states (LLS) are relaxation-favored spin population distributions of J-coupled magnetic nuclei. LLS were measured, along with classical (1)H and (15)N relaxation rate constants, in amino acids of the N-terminal Unique domain of the c-Src kinase, which is disordered in vitro under physiological conditions. The relaxation rates of LLS can probe motions and interactions in biomolecules. LLS of the aliphatic protons of glycines, with lifetimes approximately four times longer than their spin-lattice relaxation times, are reported for the first time in an intrinsically disordered protein domain. LLS relaxation experiments were integrated with 2D spectroscopy methods, further adapting them for studies on proteins.

[Comparison of 3 combinations of 0.5% levobupivacaine and 1% mepivacaine in popliteal sciatic block in hallux valgus outpatient surgery]

BACKGROUND

To compare 3 combinations of 0.5% levobupivacaine (L) and 1% mepivacaine (M) for popliteal block for hallux valgus surgery.

METHODS

Prospective, double blind study of 120 patients undergoing unilateral hallux valgus outpatient surgery with posterior popliteal block with ultrasound-guided single injection. Patients were randomly allocated into three groups: G1: 20mL L+10mL M; G2: 10mL L+20mL M; and G3: 15mL L+15mL M. Recorded variables were: time of block, onset and reversal times for tibial and peroneal nerves block; postoperative pain until the 7(th) day by means of visual analogue scale (VAS), simple descriptive scale and the quality of nocturnal rest, complications, and patient satisfaction. ANOVA and chi2 were applied in the statistical analysis, with a P<0.05 considered significant.

RESULTS

Groups were homogeneous for demographic and surgical characteristics. None of the patients required intraoperative complementary analgesia or anaesthesia. Block onset was significantly longer in G1 than in G2 and G3 (39.4±14.7 versus 32.2±16.5 and 33.2±12minutes). Recovery time from sensory and motor block was significantly longer in G1 than in G2 and G3 (29.5±9.3 versus 22.2±8.2 and 24.8±7.9hours). Postoperative pain level was below VAS 30 (1-100) in the three groups; none of the patients experienced severe pain. Maximum pain level appeared at 24h postoperatively. Patient satisfaction was high and there were no complications.

CONCLUSIONS

Block onset time and anaesthetic efficacy was adequate in the three groups. The combination of 20mL levobupivacaine 0.5% with 10mL mepivacaine 1% provide a good alternative for a lasting postoperative analgesia.

Comparison of the LMA Supreme™ with the LMA Proseal™ for airway management in patients anaesthetized in prone position

BACKGROUND

The laryngeal mask airway (LMA) has been successfully used in patients in the prone position either for rescue or elective airway management. The reusable Proseal™ LMA (PLMA) and the single use Supreme™ LMA (SLMA) have been reported to be suitable for this purpose but few comparative data are available. In this study, we compared the clinical use of both devices in adult patients anaesthetized in the prone position.

METHODS

One hundred and twenty patients undergoing surgery in the prone position were randomized to receive either the PLMA or the SLMA for airway management. Patients positioned themselves in the prone position and after pre-oxygenation, anaesthesia was induced using a target-controlled i.v. infusion of propofol and remifentanil. All PLMAs and SLMAs were inserted by experienced anaesthetists using a guided and a standard technique respectively. Ease of facemask ventilation, time and number of attempts needed for insertion, quality of ventilation, airway seal pressure, fibreoptic view, and complications were compared.

RESULTS

There were no differences between groups in insertion time or first attempt success (100% vs. 98%). The PLMA required fewer manipulations (3% vs. 15%; P=0.02) to achieve effective ventilation and provided a higher seal pressure (mean [sd] 31 [4] vs. 27 [4] cm H2O; P<0.01). The fibrescopic view of the vocal cords was similar, although easier to achieve with the PLMA. The complication rate was low and similar between the groups. Blood was present on masks in 7% vs. 8% and sore throat in 3% vs. 5% of patients with the PLMA and SLMA, respectively.

CONCLUSIONS

Airway management in patients anaesthetized in the prone position was efficient with both devices, although the PLMA required fewer manipulations and achieved a higher seal pressure.

Diffusion Barriers for Copper Metallization: Predicting Phase Stability and Reactivity using Equilibrium Thermodynamics

The guidelines for designing a conductive, amorphous material, capable of thermodynamic equilibrium with copper, are defined using readily available thermodynamic information. The tradeoff between desired properties – equilibrium at the interfaces, amorphous microstructure, and electronic conductivity – are described, along with trends in relevant binary systems that result in these properties. These guidelines defined systems for experimental study, for which preliminary results are presented.

[Outpatient or short-stay videothoracoscopy-assisted thoracic sympathectomy: anesthesia in 445 cases]

OBJECTIVE

To demonstrate the safety of outpatient or short-stay bilateral videothoracoscopy-assisted thoracic sympathectomy.

PATIENTS AND METHODS

The medical records of 445 who underwent bilateral videothoracoscopy-assisted thoracic sympathectomy were reviewed; the same protocols were used to guide these outpatient or short-stay procedures in all cases. Intravenous anesthesia was provided. An orotracheal tube allowed for carrying out the sympathectomy procedure during short periods of apnea. A 2% lidocaine solution was infused through the thoracic drains, which were removed soon after surgery. Data on intraoperative respiratory variables, pain, and intra- and postoperative complications were gathered. The data for patients undergoing the procedure on an outpatient or short-stay basis were compared.

RESULTS

No significant differences in demographic or perioperative variables were found between the 2 groups. In 3.6% of the patients in the series, there was a record of a postoperative pulmonary complication: 4 therapeutic minithoracotomies; 1 subcutaneous emphysema without radiologic changes; 9 residual pneumothoraces, 2 requiring pleural drainage; 1 chylothorax; and 1 delayed hemothorax. With the exception of the late-developing hemothorax, all complications were diagnosed and treated in the immediate postoperative period. In the outpatient surgery group, unplanned admissions because of patient refusal to leave occurred in 6.5% of the cases.

CONCLUSION

The low incidence of complications, and especially the finding that complications are detected in the early recovery period, indicate that this procedure can be performed on an outpatient basis.