Mapping lumbar efferent and afferent spinal circuitries via paddle array in a porcine model

BACKGROUND

Preclinical models are essential for identifying changes occurring after neurologic injury and assessing therapeutic interventions. Yucatan miniature pigs (minipigs) have brain and spinal cord dimensions like humans and are useful for laboratory-to-clinic studies. Yet, little work has been done to map spinal sensorimotor distributions and identify similarities and differences between the porcine and human spinal cords.

NEW METHODS

To characterize efferent and afferent signaling, we implanted a conventional 32-contact, four-column array into the dorsal epidural space over the lumbosacral spinal cord, spanning the L5-L6 vertebrae, in two Yucatan minipigs. Spinally evoked motor potentials were recorded bilaterally in four hindlimb muscles during stimulation delivered from different array locations. Then, cord dorsum potentials were recorded via the array by stimulating the left and right tibial nerves.

RESULTS

Utilizing epidural spinal stimulation, we achieved selective left, right, proximal, and distal activation in the hindlimb muscles. We then determined the selectivity of each muscle as a function of stimulation location which relates to the distribution of the lumbar motor pools.

COMPARISON WITH EXISTING METHODS

Mapping motoneuron distribution to hindlimb muscles and recording responses to peripheral nerve stimulation in the dorsal epidural space reveals insights into ascending and descending signal propagation in the lumbar spinal cord. Clinical-grade arrays have not been utilized in a porcine model.

CONCLUSIONS

These results indicate that efferent and afferent spinal sensorimotor networks are spatially distinct, provide information about the organization of motor pools in the lumbar enlargement, and demonstrate the feasibility of using clinical-grade devices in large animal research.

Post-transfusion purpura after cardiac surgery associated with veno-arterial extracorporeal membrane oxygenation

We report the case of a woman who developed post-transfusion purpura following complicated cardiac surgery requiring multiple blood product transfusions and extracorporeal life support. This case highlights the challenges of managing thrombocytopenia in patients supported with prolonged mechanical cardiovascular and renal support with ongoing blood product transfusion requirements. The differential diagnoses are broad, varied and may overlap. Whilst post-transfusion purpura is very rare, clinical signs may prompt consideration and further specific diagnostic testing. Once confirmed, management is then specific, with some aspects which are at direct variance with standard intensive care and extracorporeal life support guidelines for the management of non-specific thrombocytopenia. Consideration of the diagnosis of post-transfusion purpura early in the clinical course could help anticipate and prevent a vicious cycle of bleeding, transfusion and autoimmune-mediated platelet disruption, and may improve clinical outcomes.

Measurements of neutrino oscillation parameters from the T2K experiment using 3.6×1021 protons on target

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7 ( 16.3 ) × 10 20 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7 × 10 20 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin 2 θ 13 and the impact of priors on the δ CP measurement. Both analyses prefer the normal mass ordering and upper octant of sin 2 θ 23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin 2 θ 13 from reactors, sin 2 θ 23 = 0 . 561 - 0.032 + 0.021 using Feldman-Cousins corrected intervals, and Δ m 32 2 = 2 . 494 - 0.058 + 0.041 × 10 - 3 eV 2 using constant Δ χ 2 intervals. The CP-violating phase is constrained to δ CP = - 1 . 97 - 0.70 + 0.97 using Feldman-Cousins corrected intervals, and δ CP = 0 , π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2 σ credible level using a flat prior in δ CP , and just below 2 σ using a flat prior in sin δ CP . When the external constraint on sin 2 θ 13 is removed, sin 2 θ 13 = 28 . 0 - 6.5 + 2.8 × 10 - 3 , in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

ICARUS at the Fermilab Short-Baseline Neutrino program: initial operation

The ICARUS collaboration employed the 760-ton T600 detector in a successful 3-year physics run at the underground LNGS laboratory, performing a sensitive search for LSND-like anomalous ν e appearance in the CERN Neutrino to Gran Sasso beam, which contributed to the constraints on the allowed neutrino oscillation parameters to a narrow region around 1 eV2 . After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 the cryogenic commissioning began with detector cool down, liquid argon filling and recirculation. ICARUS then started its operations collecting the first neutrino events from the booster neutrino beam (BNB) and the Neutrinos at the Main Injector (NuMI) beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. ICARUS successfully completed its commissioning phase in June 2022. The first goal of the ICARUS data taking will be a study to either confirm or refute the claim by Neutrino-4 short-baseline reactor experiment. ICARUS will also perform measurement of neutrino cross sections with the NuMI beam and several Beyond Standard Model searches. After the first year of operations, ICARUS will search for evidence of sterile neutrinos jointly with the Short-Baseline Near Detector, within the Short-Baseline Neutrino program. In this paper, the main activities carried out during the overhauling and installation phases are highlighted. Preliminary technical results from the ICARUS commissioning data with the BNB and NuMI beams are presented both in terms of performance of all ICARUS subsystems and of capability to select and reconstruct neutrino events.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

The association of preoperative dialysis with troponin trends and short term outcomes among advanced kidney disease patients undergoing coronary artery bypass grafting

Funding Acknowledgements

Type of funding sources: None.

Introduction

Coronary artery disease continues to be the leading cause of death in patients with stage IV-V chronic kidney disease (CKD IV-V). However, the prognosis and early outcomes for advanced CKD patients undergoing coronary artery bypass grafting (CAB) worsen as the estimated glomerular filtration rate (eGFR) deteriorates. Therefore, we compared postoperative clinical outcomes and troponin trends in patients having advanced CKD according to preoperative dialysis status in a single centre experience.

Methods

A total of 51 patients with CKD IV and V who underwent CAB between 2016-2021 were included in the study. Data on patient characteristics and postoperative outcomes were collected retrospectively, and independently for our Society of Thoracic Surgeons database. Characteristics were compared between patients having CKD IV vs. CKD V. The differences in postoperative cardiac troponin trends and outcomes were evaluated between patients who did vs. did not undergo preoperative dialysis. The statistical analysis was conducted applying appropriate parametric or non-parametric (for skewed variables) testing methods, and a p value < 0.05 was considered to be statistically significant.

Results

47% (24) of subjects had CKD IV, while the rest featured CKD V. Patients with CKD IV tended to be older (61.8 ± 9.2 vs. 56.3 ± 11.5 years, p = 0.07), more obese (BMI: 31.4 ± 6.8, 27.4 ± 4.9 kg/m2, p = 0.02) and had significantly higher preoperative GFR (23 ± 4.9 vs. 9 ± 3.3 mL/min, p < 0.001) (Table.1). When comparing patients who underwent preoperative dialysis vs. those who did not, troponin levels were the highest at 18h postoperative in both groups, however, troponin levels were comparable between both groups at all time points (Table.2). Although, there was no difference in hospital length of stay and mortality between these groups, patients who did not undergo preoperative dialysis had longer intensive care unit length of stay (ICU LOS).

Conclusion

In this single centre experience preoperative dialysis was not associated with a significant difference in trends of postoperative cardiac enzymes. Although preoperative dialysis was associated with shorter ICU LOS, complex pre-procedural surgical risk assessment remains paramount in reducing complications and mortality in this high-risk population. Abstract Figure.  Abstract Figure.

Influenza vaccine uptake and attitudes of healthcare workers in Ireland

BACKGROUND

Influenza vaccination uptake by Irish healthcare workers remains sub-optimal despite local initiatives to increase it.

AIMS

To investigate hospital workers' attitudes to influenza vaccination and how this influenced their decisions about vaccination.

METHODS

A questionnaire survey of Irish hospital workers, measuring uptake of and attitudes to influenza vaccination.

RESULTS

There were 747 responders, of whom 361 (48%) reported having received influenza vaccination. Attitudes predicting vaccination uptake included a belief that vaccination would protect family members (P < 0.0005, CI 1.191-1.739), a perception of susceptibility to 'flu (P < 0.0005, CI 1.182-1.685), a belief that all healthcare workers should be vaccinated (P < 0.005, CI 1.153-1.783), perceived ease of getting 'flu vaccination at work (P < 0.0005, CI 1.851-2.842) and encouragement by line managers (P < 0.05, CI 1.018-1.400). Attitudes negatively associated with vaccination uptake included fear of needles (P < 0.05, CI 0.663-0.985) and a belief that vaccination would cause illness (P < 0.0005, CI 0.436-0.647). Medical staff were significantly more likely to be vaccinated. Healthcare students were least likely to be vaccinated (P < 0.0005).

CONCLUSION

Addressing specific barriers to influenza vaccination in healthcare workers may improve uptake.

Search for Electron Antineutrino Appearance in a Long-Baseline Muon Antineutrino Beam

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

Biomechanical properties of female dolphin reproductive tissue

Whales, dolphins, and porpoises have unusual vaginal folds of unknown function(s) that are hypothesized to play an important role in sexual selection. The potential function of vaginal folds was assessed by testing the mechanical properties of common bottlenose dolphin (Tursiops truncatus) reproductive tract tissues in 6 different regions and across age classes in post-mortem specimens. We assessed the regional (local) and overall effective elastic modulus of tissues using indentation and tensile tests, respectively. We explore the non-linear mechanical response of biological tissues, which are not often quantified. Indentation tests demonstrated that sexual maturity state, tissue region, force history, and force magnitude values significantly affected the measured effective elastic modulus. Tissue was stiffest in the vaginal fold region and overall stiffer in sexually immature compared to mature animals, likely reflecting biomechanical adaptations associated with copulation and parturition. Tensile tests showed that only tissue region significantly affected the effective modulus. Our data support the hypothesis that vaginal folds function as mechanical barriers to the penis and may provide females with mechanisms to reduce copulatory forces on other reproductive tissue. STATEMENT OF SIGNIFICANCE: Cetaceans have unusual folds of vaginal wall tissue that appear to evolve under sexual selection mechanisms and present physical barriers to the penis during copulation. We explore the biomaterial properties of vaginal fold tissue, how it varies from other reproductive tract tissues, and ontogenetic patterns. We demonstrate that vaginal folds can withstand higher mechanical forces and respond in a manner conducive to dissipating copulatory forces to other reproductive tissues. This study yields exciting insights on how female genital tissue may function during copulation, and is the first to do so in any vertebrate species. Additionally, we provide an example for testing biological tissues, non-linear properties, and materials with uneven surface structure and uneven thickness.

Search for CP Violation in Neutrino and Antineutrino Oscillations by the T2K Experiment with 2.2×10^{21} Protons on Target

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×10^{20} protons on target in the neutrino (antineutrino) mode, 89 ν_{e} candidates and seven anti-ν_{e} candidates are observed, while 67.5 and 9.0 are expected for δ_{CP}=0 and normal mass ordering. The obtained 2σ confidence interval for the CP-violating phase, δ_{CP}, does not include the CP-conserving cases (δ_{CP}=0, π). The best-fit values of other parameters are sin^{2}θ_{23}=0.526_{-0.036}^{+0.032} and Δm_{32}^{2}=2.463_{-0.070}^{+0.071}×10^{-3}  eV^{2}/c^{4}.

Combined Analysis of Neutrino and Antineutrino Oscillations at T2K

T2K reports its first results in the search for CP violation in neutrino oscillations using appearance and disappearance channels for neutrino- and antineutrino-mode beams. The data include all runs from January 2010 to May 2016 and comprise 7.482×10^{20} protons on target in neutrino mode, which yielded in the far detector 32 e-like and 135  μ-like events, and 7.471×10^{20} protons on target in antineutrino mode, which yielded 4 e-like and 66  μ-like events. Reactor measurements of sin^{2}2θ_{13} have been used as an additional constraint. The one-dimensional confidence interval at 90% for the phase δ_{CP} spans the range (-3.13, -0.39) for normal mass ordering. The CP conservation hypothesis (δ_{CP}=0, π) is excluded at 90% C.L.

Measurement of Coherent π^{+} Production in Low Energy Neutrino-Carbon Scattering

We report the first measurement of the flux-averaged cross section for charged current coherent π^{+} production on carbon for neutrino energies less than 1.5 GeV, and with a restriction on the final state phase space volume in the T2K near detector, ND280. Comparisons are made with predictions from the Rein-Sehgal coherent production model and the model by Alvarez-Ruso et al., the latter representing the first implementation of an instance of the new class of microscopic coherent models in a neutrino interaction Monte Carlo event generator. We observe a clear event excess above background, disagreeing with the null results reported by K2K and SciBooNE in a similar neutrino energy region. The measured flux-averaged cross sections are below those predicted by both the Rein-Sehgal and Alvarez-Ruso et al.

Measurement of Muon Antineutrino Oscillations with an Accelerator-Produced Off-Axis Beam

T2K reports its first measurements of the parameters governing the disappearance of ν[over ¯]_{μ} in an off-axis beam due to flavor change induced by neutrino oscillations. The quasimonochromatic ν[over ¯]_{μ} beam, produced with a peak energy of 0.6 GeV at J-PARC, is observed at the far detector Super-Kamiokande, 295 km away, where the ν[over ¯]_{μ} survival probability is expected to be minimal. Using a data set corresponding to 4.01×10^{20} protons on target, 34 fully contained μ-like events were observed. The best-fit oscillation parameters are sin^{2}(θ[over ¯]_{23})=0.45 and |Δm[over ¯]_{32}^{2}|=2.51×10^{-3}  eV^{2} with 68% confidence intervals of 0.38-0.64 and 2.26-2.80×10^{-3}  eV^{2}, respectively. These results are in agreement with existing antineutrino parameter measurements and also with the ν_{μ} disappearance parameters measured by T2K.

ATLANTIC DIP: pregnancy outcomes for women with type 1 and type 2 diabetes

ATLANTIC DIP prospectively evaluated the perinatal and maternal outcomes of pregnancies complicated by Type 1 and Type 2 diabetes during 2006/2007 in 5 antenatal centres. All women with established diabetes for at least 6 months prior to the index pregnancy and booking for antenatal care between 1/1/2006 and 31/12/2007 were included in the study. Results were collected electronically via the DIAMOND Diabetes Information System. Pregnancy outcome was compared with that of the background population receiving antenatal care in the region during the same time. There were 104 singleton pregnancies during the period of study. The stillbirth rate (SBR) of 25/1000 was 5 times greater than that reported in the background population at 5/1000 and the perinatal mortality rate (PMR) of 25/1000 was 3.5 times greater than background 7/1000. The congenital malformation rate (CMR) of 24/1000 was twice that observed in the background population. Women were not well prepared for pregnancy with 28% receiving pre pregnancy care (PPC), 43% receiving pre pregnancy folic acid and 51% achieving a HbA1C < = 7% at first antenatal visit. Pregnancy induced hypertension (PIH) and/or pre eclampsia toxaemia (PET) were three times more common than in women in the background population. In conclusion women are not well prepared for pregnancy. Maternal and infant morbidity and infant mortality are greater in women with diabetes. A regional pre pregnancy care (PPC) programme and centralised glucose management are urgently needed.

Design and validation of a multiplex specific primer-directed polymerase chain reaction assay for killer-cell immunoglobulin-like receptor genetic profiling

Current methodologies for the analysis of the killer-cell immunoglobulin-like receptor (KIR) locus utilize specific primer-directed polymerase chain reaction (SSP-PCR), which require a wide range of DNA input, multiple reaction conditions, and up to 16 individual reactions. We have developed and validated a multiplex SSP-PCR method for the genetic analysis of the KIR locus. Design and optimization of four multiplex groups targeting 14 genes and their alleles on the KIR locus has been completed. Each multiplex group contains PCR products that differ in size by a minimum of 15 bp to allow sufficient fragment length resolution for size discrimination by gel electrophoresis. This assay allows for efficient genotyping of the KIR locus while requiring a minimum amount of DNA input, utilizing the simplicity of SSP-PCR.

How to contain generalized HIV epidemics? A plea for better evidence to displace speculation

In the worst generalized HIV epidemics in East and Southern Africa, from one-quarter to three-quarters of women aged 15 years can expect to be living with HIV or to have died with AIDS by age 40 years. This disaster continues in the face of massive HIV prevention programmes based on current inexact knowledge of HIV transmission pathways and risks. To stop this disaster, both the public and public health experts need better information about the specific factors that allow HIV to propagate so extensively in countries with generalized epidemics. This knowledge could be acquired by tracing HIV infections to their source - especially tracing HIV infections in women of all ages, and tracing unexplained HIV infections in children with HIV-negative mothers.

Colonic manometry catheter placement with primary fluoroscopic guidance

The purpose of this paper is to describe our experience with a new technique of colonic manometry catheter placement using fluoroscopic guidance. Between 2000 and 2004, 44 colonic manometry catheters were placed with primary fluoroscopic guidance in 38 patients (25 males; median age, 7 years; range, 0.4-31 years) with severe defecation disorders. Fourteen colonoscopic placements were reviewed to compare the different procedures. Manometry catheters were inserted through the rectum (16 patients), cecostomy (9), ileostomy (2), and colostomy (17). Placements through diverted colons were successful in 24 of 28 (86%). Insertion through the rectum was successful in 10 of 16 (63%) fluoroscopic-guided placements vs. 12 of 14 (86%) colonoscopic placements (P=0.23). Significantly longer fluoroscopic exposure was required for fluoroscopic compared to colonoscopic placement (P=0.004). In conclusion, placement of colonic manometry catheters with primary fluoroscopic guidance is feasible in children. An important disadvantage of the fluoroscopic methodology is the prolonged fluoroscopic exposure time.

Hyperperfusion on perfusion computed tomography following revascularization for acute stroke

PURPOSE

To describe the findings of hyperperfusion on perfusion computed tomography (CT) in four patients following revascularization for acute stroke.

MATERIAL AND METHODS

In 2002-2003, among a series of 6 patients presenting with an acute stroke and treated with intra-arterial thrombolysis, we observed the presence of hyperperfusion in 3 patients on the follow-up CT perfusion. We included an additional patient who was treated with intravenous thrombolysis and who had hyperperfusion on the follow-up CT perfusion. We retrospectively analyzed their CT perfusion maps. Cerebral blood volume (CBV) and cerebral blood flow (CBF) maps were compared between the affected territory and the normal contralateral hemisphere.

RESULTS

In the four patients, the mean CBV and CBF were 3.6 +/- 2.0 ml/100 g and 39 +/- 25 ml/100 g/min in the affected territory compared to the normal side (mean CBV = 2.7 +/- 2.1 ml/100 g, mean CBF = 27 +/- 23 ml/100 g/min). There was no intracranial hemorrhage in the hyperperfused territories. At follow-up CT, some hyperperfused brain areas progressed to infarction, while others retained normal white to gray matter differentiation.

CONCLUSION

CT perfusion can demonstrate hyperperfusion, which can be seen in an ischemic brain territory following recanalization.

Atypical mycobacterial cervical lymphadenitis with extensive local spread: a surgical disease

Atypical (nontuberculous) mycobacterium is an uncommon cause of cervical lymphadenitis in immunocompetent children. Rarely, this disease progresses to locoregional destruction of the deep structures of the neck including salivary glands. Recent reports suggest medical monotherapy as an effective treatment of this disease. We report three cases of children who experienced progression to locoregional disease while on appropriate antibiotics. We suggest that the patient population to benefit from medical monotherapy has yet to be adequately defined. In our experience, surgical therapy is the only effective treatment for locoregional disease.

Multiple deprivation and excess winter deaths in Scotland

The recent publication of the Scottish Index of Multiple Deprivation (SIMD) has allowed some tentative statistical correlations to be undertaken to assess the impact poverty may have on mortality and morbidity. During the period 1989 to 2001, Scotland registered around 51,600 excess winter deaths (EWDs). An EWD is taken as the additional deaths during December to March than occurred in the preceding and subsequent four-month periods. Almost all of these EWDs were in the population aged over 65. This represents 50 more deaths per day in January than in July. The SIMD measured five criteria by region: income; employment; health and disability; education, skills and training; and geographical access to services. Glasgow was the most deprived region with an SIMD score of 46.88 and East Dunbartonshire, the least deprived region, with a score of 9.07. For the over 65s, the chance of becoming an EWD in Glasgow is one in 36, rising to one in 68 for North Ayrshire. The SIMD is positively correlated with EWD by region (0.35 at the 5% confidence level). This correlation appears to go against the influence of climatic variations, house type, energy efficiency and access to the gas network which favours urban areas. Although some of the additional winter deaths have been ascribed to outdoor cold exposure--exacerbated by inappropriate clothing or culturally determined behaviour--the majority of EWDs are premature and essentially preventable if the elderly can be kept warm in their homes during the winter months.

Synthesis and SAR of bicyclic heteroaryl hydroxamic acid MMP and TACE inhibitors

Potent and selective bicyclic heteroaryl hydroxamic acid MMP and TACE inhibitors were synthesized by a novel convergent route. Selectivity and efficacy versus MMPs and TACE could be controlled by appropriate substitution on the scaffolds and by variation of the P1' group. Select compounds were found to be effective in in vivo models of arthritis.

Cross-tolerance to otherwise lethal N-methyl-D-aspartate and oxygen-glucose deprivation in preconditioned cortical cultures

In vitro ischemic preconditioning induced by subjecting rat cortical cultures to nonlethal oxygen-glucose deprivation protects against a subsequent exposure to otherwise lethal oxygen-glucose deprivation. We provide evidence that attenuation of the postsynaptic N-methyl-D-aspartate (NMDA) receptor- and Ca(2+)-dependent neurotoxicity underlies oxygen-glucose deprivation tolerance. It is demonstrated that extended tolerance to otherwise lethal NMDA or oxygen-glucose deprivation can be induced by either of their sublethal forms of preconditioning. These four pathways are linked, since NMDA receptor blockade during preconditioning by oxygen-glucose deprivation eliminates tolerance. These results suggest that NMDA tolerance, induced by nonlethal activation of these receptors during oxygen-glucose deprivation preconditioning, underlies oxygen-glucose deprivation tolerance. Several neurotoxic downstream Ca(2+)-dependent signaling events specifically linked to NMDA receptor activation are attenuated during otherwise lethal oxygen-glucose deprivation in preconditioned cultures. Specifically, calpain activation, as well as degradation of microtubule-associated protein-2 and postsynaptic density-95, are attenuated 2 h following otherwise lethal NMDA treatment alone or oxygen-glucose deprivation in preconditioned cultures. Formation of microtubule-associated protein-2-labeled dendritic varicosities is also attenuated in preconditioned cultures within 1 h of lethal oxygen-glucose deprivation or NMDA application. Intracellular Ca(2+) levels, measured using the high- or low-affinity dyes Fluo-4 (K(d) approximately equal 345 nM) or Fluo-4FF (K(d) approximately equal 9.7 microM) respectively, are markedly attenuated during lethal oxygen-glucose deprivation in preconditioned cultures.Collectively, the results suggest the attenuation of the postsynaptic NMDA-mediated component of otherwise lethal oxygen-glucose deprivation through the suppression of Ca(2+)-dependent neurotoxic signaling, a mechanism that is initially induced by transient nonlethal activation of this receptor during ischemic preconditioning.

Policy implications for implementing evidence-based practices

The authors describe the policy and administrative-practice implications of implementing evidence-based services, particularly in public-sector settings. They review the observations of the contributors to the evidence-based practices series published throughout 2001 in Psychiatric Services. Quality and accountability have become the watchwords of health and mental health services; evidence-based practices are a means to both ends. If the objective of accountable, high-quality services is to be achieved by implementing evidence-based practices, the right incentives must be put in place, and systemic barriers must be overcome. The authors use the framework from the U.S. Surgeon General's 1999 report on mental health to describe eight courses of action for addressing the gap between science and practice: continue to build the science base; overcome stigma; improve public awareness of effective treatments; ensure the supply of mental health services and providers; ensure delivery of state-of-the-art treatments; tailor treatment to age, sex, race, and culture; facilitate entry into treatment; and reduce financial barriers to treatment.

Diagnostic and interventional ultrasound of the pediatric spine

Ultrasound is useful as a diagnostic tool in the evaluation of the pediatric spine, and can also help guide procedures in the interventional radiology suite or the operating room. This pictorial exhibit will display examples of diagnostic and interventional uses of ultrasound with respect to the pediatric spine.

Relatives' views of health care in the last year of life

This article reports the views of 155 relatives of patients who died during a 12-month period with varying degrees of palliative care service (hospital-based, home care and no palliative care). Although overall care was rated as excellent or good by the majority of interviewees, the Critical Incident Technique (Flanagan, 1954) was used to gather examples of good and poor care from relatives' perspectives. These incidents are recounted here under a framework describing the process of care from access to services through to care at the time of death and aftercare for relatives. The range of incidents reported suggest that relatives consider all aspects of care - technical and interpersonal - as important towards the end of life, but particular importance is placed on the attitudinal and dignity-preserving aspects of care. The movement to integrate principles of palliative care into all clinical practice is reinforced by the findings from this study.

The discovery of anthranilic acid-based MMP inhibitors. Part 2: SAR of the 5-position and P1(1) groups

A novel series of anthranilic acid-based inhibitors of MMP-1, MMP-9, MMP-13, and TACE was prepared and evaluated. Selective inhibitors of MMP-9, MMP-13, and TACE were identified, including the potent, orally active MMP-13 inhibitor 4p.