Clinical and laboratory characteristics of patients hospitalized with severe COVID-19 in New Orleans, August 2020 to September 2021.

Louisiana experienced high morbidity and mortality from COVID-19. To assess possible explanatory factors, we conducted a cohort study (ClinSeqSer) of patients hospitalized with COVID-19 in New Orleans during August 2020-September 2021. Following enrollment, we reviewed medical charts, and performed SARS-CoV-2 RT-PCR testing on nasal and saliva specimens. We used multivariable logistic regression to assess associations between patient characteristics and severe illness, defined as ≥ 6 L/min oxygen or intubation. Among 456 patients, median age was 56 years, 277 (60.5%) were Black non-Hispanic, 436 (95.2%) had underlying health conditions, and 358 were unvaccinated (92.0% of 389 verified). Overall, 187 patients (40.1%) had severe illness; 60 (13.1%) died during admission. In multivariable models, severe illness was associated with age ≥ 65 years (OR 2.08, 95% CI 1.22-3.56), hospitalization > 5 days after illness onset (OR 1.49, 95% CI 1.01-2.21), and SARS CoV-2 cycle threshold (Ct) result of < 32 in saliva (OR 4.79, 95% CI 1.22-18.77). Among patients who were predominantly Black non-Hispanic, unvaccinated and with underlying health conditions, approximately 1 in 3 patients had severe COVID-19. Older age and delayed time to admission might have contributed to high case-severity. An association between case-severity and low Ct value in saliva warrants further investigation.

Hypotension and respiratory events related to electrical cardioversion for atrial fibrillation or atrial flutter in the emergency department.

INTRODUCTION: Electrical cardioversion for atrial fibrillation/atrial flutter (AF/AFL) is common in the ED. Our previous work showed that hypotension and respiratory events were important adverse events that occurred in patients undergoing electrical cardioversion for AF/AFL. The purpose of this study was to examine if (1) beta-blockers or calcium channel blocker use prior to ECV were associated with hypotension and (2) medications used for procedural sedation were associated with respiratory events. METHODS: This was a secondary analysis of pooled study data from four previous multicentred studies on AF/AFL. We conducted a multivariable logistic regression to examine predictors of hypotension and respiratory adverse events. RESULTS: There were 1736 patients who received ECV. A hypotensive event occurred in 62 (3.6%) patients. There was no significant difference in the odds of a hypotensive event in patients who received a beta-blocker or calcium channel blocker in the ED compared to no rate control. Procedural sedation with fentanyl (OR 2.01 95% CI 1.15-3.51) and home beta-blocker use (OR 1.92, 95% CI 1.14-3.21) were significantly associated with hypotensive events. A respiratory event occurred in 179 (10.3%) patients. Older age (OR 2.02, 95% CI 1.30- 3.15) and receiving midazolam for procedural sedation were found to be significantly associated with respiratory events (OR 1.99, 95% CI 1.02-3.88). CONCLUSION: Beta-blocker or calcium channel blocker use prior to ECV for AF/AFL was not associated with hypotension. However, sedation with fentanyl and home beta-blocker use was associated with hypotension. The use of midazolam for procedural sedation was significantly associated with respiratory events.

RéSUMé: INTRODUCTION: La cardioversion électrique pour la fibrillation auriculaire / flutter auriculaire (AF / AFL) est fréquente aux urgences. Nos travaux précédents ont montré que l'hypotension et les événements respiratoires étaient des événements indésirables importants qui se sont produits chez les patients subissant une cardioversion électrique pour AF / AFL. Le but de cette étude était d'examiner si 1) les bêtabloquants ou les inhibiteurs calciques utilisés avant l'ECV étaient associés à l'hypotension et 2) les médicaments utilisés pour la sédation procédurale sont associés à des événements respiratoires. MéTHODES: Il s'agissait d'une analyse secondaire des données d'études regroupées de quatre études multicentriques précédentes sur l'AF/AFL. Nous avons effectué une régression logistique multivariée pour examiner les prédicteurs de l'hypotension et des événements indésirables respiratoires. RéSULTATS: Il y avait 1736 patients qui ont reçu ECV. Un événement hypotenseur s'est produit dans 62 (3,6%) patients. Il n'y avait pas de différence significative dans la probabilité d'un événement hypotenseur chez les patients qui ont reçu un bêtabloquant ou un inhibiteur calcique à l'urgence par rapport à aucun contrôle de taux. La sédation procédurale avec du fentanyl (RC 2,01 à 95 %, IC 1,15 à 3,51) et l'utilisation de bêtabloquants à domicile (RC 1,92, IC à 95 %, 1,14 à 3,21) étaient significativement associées à des événements hypotensifs. Un événement respiratoire est survenu chez 179 (10,3 %) patients. Un âge plus avancé (RC 2,02, IC à 95 % : 1,30 à 3,15) et la réception de midazolam pour sédation procédurale étaient significativement associés à des événements respiratoires (RC 1,99, IC à 95 % 1,02-3,88). CONCLUSIONS: L'utilisation d'un bêtabloquant ou d'un inhibiteur calcique avant l'ECV pour l'AF/AFL n'était pas associée à l'hypotension. Cependant, la sédation avec du fentanyl et l'utilisation de bêtabloquants à domicile étaient associées à l'hypotension. L'utilisation du midazolam pour la sédation procédurale était significativement associée aux événements respiratoires.

Delayed intracranial hemorrhage after head injury among elderly patients on anticoagulation seen in the emergency department.

INTRODUCTION: Elderly patients on oral anticoagulation are commonly seen in emergency departments (EDs). Oral anticoagulation, particularly warfarin, is associated with an increased risk of intracranial hemorrhage after head trauma. Data on delayed bleeds in anticoagulated patients are limited. The objective of this study was to examine risk of delayed intracranial hemorrhage in patients presenting to the ED with a head injury anticoagulated with warfarin or a direct oral anticoagulant, compared to patients not anticoagulated. METHODS: Cohort study using administrative data from Ontario of patients ≥ 65 years presenting to the ED with a complaint of head injury between 2016 and 2018. The primary outcome was delayed intracranial hemorrhage, defined as a new ICD-10 code for intracranial hemorrhage within 90 days of the initial ED visit for a head injury where no intracranial hemorrhage was diagnosed. The main exposure variable was oral anticoagulation use, which was a three-level variable (warfarin, direct oral anticoagulants, or no oral anticoagulation). We used multivariable logistic regression to determine the odds of delayed intracranial hemorrhage based on anticoagulation status. RESULTS: 69,321 patients were included: 58,233 (84.0%) had not been prescribed oral anticoagulation, 3081 (4.4%) had a warfarin prescription, and 8007 (11.6%) had a direct oral anticoagulant prescription. Overall, 718 (1.0%) patients had a delayed intracranial hemorrhage within 90 days of ED visit for head injury. Among patients not anticoagulated, 586 (1.0%) had a delayed intracranial hemorrhage, 54 (1.8%) patients on warfarin, and 78 (1.0%) patients on a direct oral anticoagulant had a delayed intracranial hemorrhage. There was an increased odds of delayed intracranial hemorrhage with warfarin use compared with no anticoagulation (OR 1.5, 95% CI 1.1-2.1). There was no association between delayed intracranial hemorrhage and direct oral anticoagulant use compared to no anticoagulation (OR 0.9, 95% CI 0.6-1.1). CONCLUSIONS: There was an increased odds of delayed intracranial hemorrhage within 90 days in older ED head injured patients prescribed warfarin compared to patients not on anticoagulation. direct oral anticoagulant use was not associated with increased risk of delayed intracranial hemorrhage.

RéSUMé: INTRODUCTION: Les patients âgés sous anticoagulation orale sont fréquemment accueillis dans les services d'urgence. L'anticoagulation orale, en particulier la warfarine, est associée à un risque accru d'hémorragie intracrânienne après un traumatisme crânien. Les données sur les saignements retardés chez les patients anticoagulés sont limitées. L'objectif de cette étude était d'examiner le risque d'hémorragie intracrânienne tardive chez les patients se présentant aux urgences avec un traumatisme crânien et anticoagulés avec de la warfarine ou un anticoagulant oral direct, par rapport aux patients non anticoagulés. MéTHODES: Étude de cohorte utilisant les données administratives de l'Ontario des patients ≥ 65 ans se présentant aux urgences avec une plainte de traumatisme crânien entre 2016 et 2018. L'issue primaire était l'hémorragie intracrânienne tardive, définie comme un nouveau code CIM-10 pour une hémorragie intracrânienne dans les 90 jours suivant la visite initiale aux urgences où aucune hémorragie intracrânienne n'a été diagnostiquée. La principale variable d'exposition était le recours à l'anticoagulation orale, qui était une variable à trois niveaux (warfarine, anticoagulants oraux directs ou pas d'anticoagulation orale). Nous avons utilisé une régression logistique multivariable pour déterminer les chances d'hémorragie intracrânienne tardive en fonction du statut d'anticoagulation. RéSULTATS: 69 321 patients ont été inclus : 58 233 (84,0 %) n'avaient pas reçu de prescription d'anticoagulant oral, 3 081 (4,4 %) avaient une prescription de warfarine et 8 007 (11,6 %) avaient une prescription directe d'anticoagulant oral. Dans l'ensemble, 718 (1,0 %) patients ont présenté une hémorragie intracrânienne tardive dans les 90 jours suivant leur visite aux urgences pour un traumatisme crânien. Parmi les patients non anticoagulés, 586 (1,0 %) ont eu une hémorragie intracrânienne retardée, 54 (1,8 %) patients sous warfarine et 78 (1,0 %) patients sous anticoagulant oral direct ont eu une hémorragie intracrânienne retardée. Le risque d'hémorragie intracrânienne tardive était plus élevé avec l'utilisation de la warfarine qu'en l'absence d'anticoagulation (OR : 1,5, IC 95 % : 1,1-2,1). Il n'y avait pas d'association entre l'hémorragie intracrânienne tardive et l'utilisation d'anticoagulants oraux directs par rapport à l'absence d'anticoagulation (OR : 0,9, IC 95 % : 0,6-1,1). CONCLUSIONS: Il y avait une probabilité accrue d'hémorragie intracrânienne retardée dans les 90 jours chez les patients plus âgés victimes d'un traumatisme crânien aux urgences à qui l'on avait prescrit de la warfarine que chez les patients qui n'étaient pas sous anticoagulation. L'utilisation d'anticoagulants oraux directs n'était pas associée à un risque accru d'hémorragie intracrânienne tardive.

Overestimation of benefit when clinical trials stop early: a simulation study.

BACKGROUND: Stopping trials early because of a favourable interim analysis can exaggerate benefit. This study simulated trials typical of those stopping early for benefit in the real world and estimated the degree to which early stopping likely overestimates benefit. METHODS: From 1 million simulated trials, we selected those trials that exceeded interim stopping criteria, and compared apparent benefit when stopped with the true benefit used to generate the data. Each simulation randomly assigned period of observation, number of subjects, and control event rate using normal distributions centred on the same parameters in a template trial typical of real-world "truncated" (i.e. stopped for benefit) trials. The intervention's true relative risk reduction (RRR) was also randomized, and assumed 1% of drugs have a warfarin-like effect (60% RRR), 5% a statin-like effect (35% RRR), 39% an ASA-like effect (15% RRR), 50% no effect (0% RRR), and that 5% would cause harm (modelled as a 20% relative risk increase). Trials had a single interim analysis and a z-value for stopping of 2.782 (O'Brien-Fleming threshold). We also modelled (1) a large truncated trial based on the SPRINT blood pressure trial (using SPRINT's parameters and stopping criteria) and (2) the same typical truncated trials if they instead went to completion as planned with no interim analysis. RESULTS: For typical truncated trials, the true RRR was roughly 2/3 the observed RRR at the time of stopping. RRR was overestimated by an absolute 14.9% (median, IQR 6.4-24.6) in typical truncated trials, by 5.3% (IQR -0.1 to 11.4) in the same trials if instead carried to completion, and by 2.3% (IQR 0.98-1.09) in large SPRINT-like trials. For all models, to keep the absolute RRR overestimate below 5%, 250 events were required. CONCLUSION: Simulated trials typical of those stopping early for benefit overestimate the true relative risk reduction by roughly 50% (i.e. the true RRR was 2/3 of the observed value). Overestimation was much smaller, and likely unimportant, when simulating large SPRINT-like trials stopping early. Whether trials were large or small, stopped early or not, a minimum 250 events were needed to avoid overestimating relative risk reduction by an absolute 5% or more.

Interpreting abdominal fluid in colic horses: Understanding and applying peritoneal fluid evidence.

BACKGROUND: Interpreting changes in peritoneal fluid helps clinicians manage colic and other diseases in horses. During abdominal problems in the horse, abdominal fluid characteristics such as color, turbidity, total nucleated and red blood cell counts, cytology, total protein, and l-lactate change in predictable ways, helping the clinician characterize the disease. DESCRIPTION: Normal abdominal fluid in horses is odorless, clear to light yellow in color, and transparent. Peritoneal fluid becomes more turbid with increasing levels of protein, number of WBCs or RBCs, or with gross contamination following intestinal rupture. The color of abdominal fluid will also change with the type and quantity of cells or other elements present. The transformation of peritoneal fluid color from golden to orange to red represents increasing levels of RBCs, common with strangulating intestinal lesions. Serosanguinous defines fluid that is both turbid and orange to bloody because of increased total protein, WBCs, and RBCs, and is considered classic for diseases characterized by intestinal ischemia. Peritoneal fluid may also be red or blood-colored because of a hemoperitoneum, or secondary to blood contamination during sample collection. l-Lactate measurement in the abdominal fluid has proven invaluable for the identification of strangulating intestinal injury. Cytology acts as an important supplement to cell counts in peritoneal fluid, and the normal ratio of non-degenerate neutrophils:mononuclear cells of 2:1 changes during various gastrointestinal diseases. Culture of peritoneal fluid samples should be performed when septic peritonitis is suspected. SUMMARY: Abdominal fluid is a sensitive indicator of intestinal injury and a useful tool to direct treatment. Peritoneal fluid evaluation includes gross visual and olfactory examination, nucleated cell count, total protein, RBC count, lactate levels, cytology, and culture. The changes noted in such variables are related to the type and duration of the abdominal problem. KEY POINTS:  Abdominal fluid interpretation has become central to the triage and management of challenging equine colic patients.  The transformation of peritoneal fluid color from golden to orange to red represents increasing levels of RBCs, common with strangulating intestinal lesions.  Contamination with RBCs at various concentrations may be secondary to vascular (eg, abdominal wall or mesenteric vessels) or splenic trauma during abdominal fluid collection; however, this must be distinguished from orange to red fluid associated with intestinal strangulating obstruction or hemoabdomen  Peritoneal fluid analysis reveals abdominal pathology by recognizing specific changes that occur with disease processes affecting the tissues and organs within this cavity.  Abdominal fluid examination should be used as a tool to direct treatment rather than the definitive test for diagnosis of the acute abdomen  Septic peritonitis in horses most commonly originates secondary to intestinal compromise or accidents (vascular damage, perforation, or surgical manipulation), leading to bacterial translocation into the abdomen.

Abdominocentesis techniques in horses.

BACKGROUND: Abdominocentesis is commonly used to evaluate the abdominal cavity of the horse. This technique provides valuable diagnostic information as well as the means to monitor patients with abdominal diseases being managed medically and to determine their need for surgical management. Complications are uncommon and include trauma to the gastrointestinal tract or spleen, septic peritonitis, or abdominal wall infection. PROCEDURES: This review describes the indications, utility, patient preparation, and instructions for performing abdominocentesis as well as possible complications reported in horses. Step-by-step instructions are provided for the two most commonly used abdominocentesis techniques in horses, which include the use of a needle (18 Ga, 3.8 cm [1.5 in]) and a teat cannula (9.5 cm [3.75 in]). SUMMARY: Peritoneal fluid collection and fluid analysis can be used to confirm diagnosis of intraabdominal pathology including inflammatory, infectious, neoplastic, obstructive, and bowel strangulation, leading to additional diagnostic and therapeutic plans. KEY POINTS: Abdominocentesis is useful as a diagnostic procedure in horses suffering from colic, diarrhea, weight loss, or other conditions involving the abdominal cavity and is an integral component of diagnostic testing for colic at referral institutions or in the field. Abdominal fluid collection using an 18-Ga, 3.8-cm (1.5-in) needle is recommended for adult horses because the needle is long enough to penetrate the peritoneal cavity. The teat cannula technique is recommended for use in adult horses, foals, and miniature horses to reduce the risk of enterocentesis, even though this procedure is more traumatic than using an 18-Ga, 3.8-cm needle. Ultrasonography of the abdomen is a valuable tool in the assessment of any horse with signs of colic, but it is not essential for performing an abdominocentesis successfully.

Collection and administration of blood products in horses: Transfusion indications, materials, methods, complications, donor selection, and blood testing.

BACKGROUND: Blood transfusion is a lifesaving treatment for horses with acute hemorrhage and other causes of anemia. Transfusions improve oxygen delivery to the tissues via increased blood volume and hemoglobin concentration. Certain aspects of equine blood transfusion are challenging, especially in the field situation, and practitioners may be unfamiliar or feel overwhelmed with the process. An understanding of the indications, materials, methods, and techniques as well as donor selection and possible complications will help practitioners successfully implement blood transfusion in clinical practice. PROCEDURES: Blood transfusion involves several steps including appropriate donor selection, cross-matching, blood collection, and administration, as well as monitoring and handling of transfusion reactions. Guidance for each of these steps are detailed in this review. SUMMARY: Blood transfusion is an effective and often lifesaving treatment for managing diseases of blood loss, hemolysis, and decreased RBC production. Equine practitioners require a thorough understanding of the indications for blood transfusion, the immunological principles behind compatibility testing and transfusion reactions, and the technical skills to aseptically collect and administer blood products KEY POINTS: Equine practitioners require a thorough understanding of the indications for blood transfusion, the immunological principles behind compatibility testing and transfusion reactions, and the technical skills to aseptically collect and administer blood products. Because there are over 400,000 possible equine RBC phenotypes, no universal donor exists, and some blood type incompatibilities are likely between any donor and recipient. Therefore, prior to any blood transfusion, donor and recipient blood should be cross-matched Inadequate delivery of oxygen (Do2 ) to the tissues, resulting from low hemoglobin (Hb) concentration, is the most important indication for blood transfusion Neonatal isoerythrolysis most commonly occurs following an anamnestic response in late gestation; it rarely occurs following a primary exposure because the immune response is not strong enough to produce clinically significant alloantibody titers.

Functional role of brain-engrafted macrophages against brain injuries.

BACKGROUND: Brain-resident microglia have a distinct origin compared to macrophages in other organs. Under physiological conditions, microglia are maintained by self-renewal from the local pool, independent of hematopoietic progenitors. Pharmacological depletion of microglia during whole-brain radiotherapy prevents synaptic loss and long-term recognition memory deficits. However, the origin or repopulated cells and the mechanisms behind these protective effects are unknown. METHODS: CD45low/int/CD11b+ cells from naïve brains, irradiated brains, PLX5622-treated brains and PLX5622 + whole-brain radiotherapy-treated brains were FACS sorted and sequenced for transcriptomic comparisons. Bone marrow chimeras were used to trace the origin and long-term morphology of repopulated cells after PLX5622 and whole-brain radiotherapy. FACS analyses of intrinsic and exotic synaptic compartments were used to measure phagocytic activities of microglia and repopulated cells. In addition, concussive brain injuries were given to PLX5622 and brain-irradiated mice to study the potential protective functions of repopulated cells after PLX5622 + whole-brain radiotherapy. RESULTS: After a combination of whole-brain radiotherapy and microglia depletion, repopulated cells are brain-engrafted macrophages that originate from circulating monocytes. Comparisons of transcriptomes reveal that brain-engrafted macrophages have an intermediate phenotype that resembles both monocytes and embryonic microglia. In addition, brain-engrafted macrophages display reduced phagocytic activity for synaptic compartments compared to microglia from normal brains in response to a secondary concussive brain injury. Importantly, replacement of microglia by brain-engrafted macrophages spare mice from whole-brain radiotherapy-induced long-term cognitive deficits, and prevent concussive injury-induced memory loss. CONCLUSIONS: Brain-engrafted macrophages prevent radiation- and concussion-induced brain injuries and cognitive deficits.

Successful Clearance of 300 Day SARS-CoV-2 Infection in a Subject with B-Cell Depletion Associated Prolonged (B-DEAP) COVID by REGEN-COV Anti-Spike Monoclonal Antibody Cocktail.

A 59-year-old male with follicular lymphoma treated by anti-CD20-mediated B-cell depletion and ablative chemotherapy was hospitalized with a COVID-19 infection. Although the patient did not develop specific humoral immunity, he had a mild clinical course overall. The failure of all therapeutic options allowed infection to persist nearly 300 days with active accumulation of SARS-CoV-2 virus mutations. As a rescue therapy, an infusion of REGEN-COV (10933 and 10987) anti-spike monoclonal antibodies was performed 270 days from initial diagnosis. Due to partial clearance after the first dose (2.4 g), a consolidation dose (8 g) was infused six weeks later. Complete virus clearance could then be observed over the following month, after he was vaccinated with the Pfizer-BioNTech anti-COVID-19 vaccination. The successful management of this patient required prolonged enhanced quarantine, monitoring of virus mutations, pioneering clinical decisions based upon close consultation, and the coordination of multidisciplinary experts in virology, immunology, pharmacology, input from REGN, the FDA, the IRB, the health care team, the patient, and the patient's family. Current decisions to take revolve around patient's follicular lymphoma management, and monitoring for virus clearance persistence beyond disappearance of REGEN-COV monoclonal antibodies after anti-SARS-CoV-2 vaccination. Overall, specific guidelines for similar cases should be established.

Impact of Zika virus on the human type I interferon osteoimmune response.

BACKGROUND: The developing field of osteoimmunology supports importance of an interferon (IFN) response pathway in osteoblasts. Clarifying osteoblast-IFN interactions is important because IFN is used as salvage anti-tumor therapy but systemic toxicity is high with variable clinical results. In addition, osteoblast response to systemic bursts and disruptions of IFN pathways induced by viral infection may influence bone remodeling. ZIKA virus (ZIKV) infection impacts bone development in humans and IFN response in vitro. Consistently, initial evidence of permissivity to ZIKV has been reported in human osteoblasts. HYPOTHESIS: Osteoblast-like Saos-2 cells are permissive to ZIKV and responsive to IFN. METHODS: Multiple approaches were used to assess whether Saos-2 cells are permissive to ZIKV infection and exhibit IFN-mediated ZIKV suppression. Proteomic methods were used to evaluate impact of ZIKV and IFN on Saos-2 cells. RESULTS: Evidence is presented confirming Saos-2 cells are permissive to ZIKV and support IFN-mediated suppression of ZIKV. ZIKV and IFN differentially impact the Saos-2 proteome, exemplified by HELZ2 protein which is upregulated by IFN but non responsive to ZIKV. Both ZIKV and IFN suppress proteins associated with microcephaly/pseudo-TORCH syndrome (BI1, KI20A and UBP18), and ZIKV induces potential entry factor PLVAP. CONCLUSIONS: Transient ZIKV infection influences osteoimmune state, and IFN and ZIKV activate distinct proteomes in Saos-2 cells, which could inform therapeutic, engineered, disruptions.

Quality of warfarin management in primary care: Determining the stability of international normalized ratios using a nationally representative prospective cohort.

OBJECTIVE: To determine the stability of warfarin anticoagulation using a nationally representative sample of Canadian primary care patients and providers. DESIGN: Prospective cohort study. SETTING: Primary care practices associated with the Canadian Primary Care Sentinel Surveillance Network. PARTICIPANTS: Adult warfarin users with 7 or more evaluable international normalized ratio (INR) readings. MAIN OUTCOMES MEASURES: International normalized ratio time in therapeutic range (TTR) determined using the Rosendaal method; TTR above 75% was considered good INR control and TTR below 60% was considered poor INR control. The primary outcome was the proportion of all warfarin users (using an INR target range of 2.0 to 3.5) with good INR control during their first year taking warfarin who have poor INR control the following year. Secondary outcomes included the TTR using an INR target of 2.0 to 3.0 when restricted to patients with known atrial fibrillation (AF) or venous thromboembolism (VTE); and the proportion of INR values below the target of 2.0 and above the targets of 3.0 and 3.5 in the year before the availability of other oral anticoagulants. RESULTS: Among 18 303 adult warfarin users (mean age of 71.0 years, 46.6% female), the median TTR (INR target range of 2.0 to 3.5) was 77.4% (interquartile range of 64.6% to 86.4%). The TTR was above 75% in 56.0% of patients and below 60% in 19.3% of patients. Of those exhibiting good INR control in year 1 of anticoagulation therapy, only 10.2% had poor control the following year. When restricted to patients with known AF or VTE (89.7% with AF and 13.5% with VTE), and assuming an INR target range of 2.0 to 3.0, the TTR was 67.8% (interquartile range of 54.8% to 77.9%). Of these patients, 27.9% had INR values below 2.0, and 19.4% and 8.6% had values above 3.0 and 3.5, respectively. CONCLUSION: Primary care warfarin management produces a TTR comparable to that in randomized trials, with out-of-range INR values 3 times more likely to predispose to thrombosis (INR of < 2.0) than to hemorrhage (INR of > 3.5). A history of good INR control does predict future INR stability and meaningfully informs decisions to switch established warfarin users onto newer agents.

Inhibition of p70 ribosomal S6 kinase 1 (S6K1) by PF-4708671 decreased infarct size in early cerebral ischemia-reperfusion with decreased BBB permeability.

It is not clear whether inhibition of p70 ribosomal S6 kinase 1 (S6K1) is neuroprotective in cerebral ischemia-reperfusion. Decreasing blood-brain barrier (BBB) disruption has been associated with a better neuronal outcome in cerebral ischemia. We hypothesized that inhibition of S6K1 would decrease BBB disruption and infarct size in the early stage of cerebral ischemia-reperfusion. Middle cerebral artery occlusion (MCAO) was performed in rats under isoflurane anesthesia with controlled ventilation. 75 mg/kg of PF-4708671, an S6K1 inhibitor, was administered intraperitoneally 15 min after MCAO. After 1 h of MCAO and 2 h of reperfusion, the transfer coefficient (Ki) of 14C-α-aminoisobutyric acid and the volume of 3H-dextran distribution were determined to assess the degree of BBB disruption. At the same time point, phosphorylated Rictor (pT1135) and the infarct size were measured to evaluate S6K1 activity. In the PF-4708671 treated rats, the Ki of the ischemic-reperfused cortex was lower than the untreated rats (-22%, P < 0.05) and the volume of dextran distribution was significantly lower in most brain regions. With PF-4708671, a significant decrease in pT1135 Rictor was observed and the percentage of cortical infarct out of total cortical area was decreased (11.6 ±â€¯2.0% vs 7.2 ±â€¯1.1%, P < 0.0001). Our data demonstrate that PF-4708671 decreased the size of the cortical infarct in the ischemic-reperfused cortex with a decrease in BBB disruption suggesting that inhibition of S6K1 may induce neuronal survival in early cerebral ischemia-reperfusion and that a decrease of BBB disruption could be one of the contributing factors.

Rescue of cognitive function following fractionated brain irradiation in a novel preclinical glioma model.

More than half of long-term brain tumor survivors develop irreversible cognitive decline that severely affect their quality of life. However, there is no pre-clinical model that allows long-term assessment of cognition, and there is no treatment which ameliorates cognitive deficits in patients. Here, we report a novel glioma mouse model that offers manageable tumor growth and reliable assessment of cognitive functions in a post-treatment manner. Using this model, we found that fractionated whole-brain irradiation (fWBI), but not tumor growth, results in memory deficits. Transient inhibition of CSF-1R during fWBI prolongs survival of glioma-bearing mice and fully prevents fWBI-induced memory deficits. This result suggests that CSF-1R inhibition during radiotherapy can be explored as an approach to improve both survival and cognitive outcomes in patients who will receive fWBI. Taken together, the current study provides a proof of concept of a powerful tool to study radiation-induced cognitive deficits in glioma-bearing animals.

mTORC2 modulates the amplitude and duration of GFAT1 Ser-243 phosphorylation to maintain flux through the hexosamine pathway during starvation.

The mechanistic target of rapamycin (mTOR) controls metabolic pathways in response to nutrients. Recently, we have shown that mTOR complex 2 (mTORC2) modulates the hexosamine biosynthetic pathway (HBP) by promoting the expression of the key enzyme of the HBP, glutamine:fructose-6-phosphate aminotransferase 1 (GFAT1). Here, we found that GFAT1 Ser-243 phosphorylation is also modulated in an mTORC2-dependent manner. In response to glutamine limitation, active mTORC2 prolongs the duration of Ser-243 phosphorylation, albeit at lower amplitude. Blocking glycolysis using 2-deoxyglucose robustly enhances Ser-243 phosphorylation, correlating with heightened mTORC2 activation, increased AMPK activity, and O-GlcNAcylation. However, when 2-deoxyglucose is combined with glutamine deprivation, GFAT1 Ser-243 phosphorylation and mTORC2 activation remain elevated, whereas AMPK activation and O-GlcNAcylation diminish. Phosphorylation at Ser-243 promotes GFAT1 expression and production of GFAT1-generated metabolites including ample production of the HBP end-product, UDP-GlcNAc, despite nutrient starvation. Hence, we propose that the mTORC2-mediated increase in GFAT1 Ser-243 phosphorylation promotes flux through the HBP to maintain production of UDP-GlcNAc when nutrients are limiting. Our findings provide insights on how the HBP is reprogrammed via mTORC2 in nutrient-addicted cancer cells.

New therapeutic approaches for brainstem tumors: a comparison of delivery routes using nanoliposomal irinotecan in an animal model.

Despite the advances in imaging, surgery and radiotherapy, the majority of patients with brainstem gliomas die within 2 years after initial diagnosis. Factors that contribute to the dismal prognosis of these patients include the infiltrative nature and anatomic location in an eloquent area of the brain, which prevents total surgical resection and the presence of the blood-brain barrier (BBB), which reduces the distribution of systemically administered agents. The development of new therapeutic approaches which can circumvent the BBB is a potential path to improve outcomes for these children. Convection-enhanced delivery (CED) and intranasal delivery (IND) are strategies that permit direct drug delivery into the central nervous system and are an alternative to intravenous injection (IV). We treated rats bearing human brainstem tumor xenografts with nanoliposomal irinotecan (CPT-11) using CED, IND, and IV. A single treatment of CED irinotecan had a similar effect on overall survival as multiple treatments by IV route. IND CPT-11 showed significantly increased survival of animals with brainstem tumors, and demonstrated the promise of this non-invasive approach of drug delivery bypassing the BBB when combined with nanoliposomal chemotherapy. Our results indicated that using CED and IND of nanoliposomal therapy increase likelihood of practical therapeutic approach for the treatment of brainstem gliomas.

Colony-stimulating factor 1 receptor blockade prevents fractionated whole-brain irradiation-induced memory deficits.

BACKGROUND: Primary central nervous system (CNS) neoplasms and brain metastases are routinely treated with whole-brain radiation. Long-term survival occurs in many patients, but their quality of life is severely affected by the development of cognitive deficits, and there is no treatment to prevent these adverse effects. Neuroinflammation, associated with activation of brain-resident microglia and infiltrating monocytes, plays a pivotal role in loss of neurological function and has been shown to be associated with acute and long-term effects of brain irradiation. Colony-stimulating factor 1 receptor (CSF-1R) signaling is essential for the survival and differentiation of microglia and monocytes. Here, we tested the effects of CSF-1R blockade by PLX5622 on cognitive function in mice treated with three fractions of 3.3 Gy whole-brain irradiation. METHODS: Young adult C57BL/6J mice were given three fractions of 3.3 Gy whole-brain irradiation while they were on diet supplemented with PLX5622, and the effects on periphery monocyte accumulation, microglia numbers, and neuronal functions were assessed. RESULTS: The mice developed hippocampal-dependent cognitive deficits at 1 and 3 months after they received fractionated whole-brain irradiation. The impaired cognitive function correlated with increased number of periphery monocyte accumulation in the CNS and decreased dendritic spine density in hippocampal granule neurons. PLX5622 treatment caused temporary reduction of microglia numbers, inhibited monocyte accumulation in the brain, and prevented radiation-induced cognitive deficits. CONCLUSIONS: Blockade of CSF-1R by PLX5622 prevents fractionated whole-brain irradiation-induced memory deficits. Therapeutic targeting of CSF-1R may provide a new avenue for protection from radiation-induced memory deficits.

Age exacerbates the CCR2/5-mediated neuroinflammatory response to traumatic brain injury.

BACKGROUND: Traumatic brain injury (TBI) is a major risk factor for the development of multiple neurodegenerative diseases, including Alzheimer's disease (AD) and numerous recent reports document the development of dementia after TBI. Age is a significant factor in both the risk of and the incidence of acquired brain injury. TBI-induced inflammatory response is associated with activation of brain resident microglia and accumulation of infiltrating monocytes, which plays a pivotal role in chronic neurodegeneration and loss of neurological function after TBI. Despite the extensive clinical evidence implicating neuroinflammation with the TBI-related sequelae, the specific role of these different myeloid cells and the influence of age on TBI-initiated innate immune response remain unknown and poorly studied. METHODS: We used gene profiling and pathway analysis to define the effect of age on inflammatory response at the time of injury. The recruitment of peripheral CCR2(+) macrophages was delineated using the CX3CR1 (GFP/+) CCR2 (RFP/+) reporter mouse. These responses were examined in the context of CCR2/5 antagonism using cenicriviroc. RESULTS: Unsupervised gene clustering and pathway analysis revealed that age predisposes exacerbated inflammatory response related to the recruitment and activation of peripheral monocytes to the injured brain. Using a unique reporter animal model able to discriminate resident versus peripherally derived myeloid cells, we demonstrate that in the aged brain, there is an increased accumulation of peripherally derived CCR2(+) macrophages after TBI compared to young animals. Exaggerated recruitment of this population of cells was associated with an augmented inflammatory response in the aged TBI animals. Targeting this cellular response with cenicriviroc, a dual CCR2/5 antagonist, significantly ameliorated injury-induced sequelae in the aged TBI animals. CONCLUSIONS: Importantly, these findings demonstrate that peripheral monocytes play a non-redundant and contributing role to the etiology of trauma-induced inflammatory sequelae in the aged brain.

CCR2 antagonism alters brain macrophage polarization and ameliorates cognitive dysfunction induced by traumatic brain injury.

Traumatic brain injury (TBI) is a major risk factor for the development of multiple neurodegenerative diseases. With respect to the increasing prevalence of TBI, new therapeutic strategies are urgently needed that will prevent secondary damage to primarily unaffected tissue. Consistently, neuroinflammation has been implicated as a key mediator of secondary damage following the initial mechanical insult. Following injury, there is uncertainty regarding the role that accumulating CCR2(+) macrophages play in the injury-induced neuroinflammatory sequelae and cognitive dysfunction. Using CX3CR1(GFP/+)CCR2(RFP/+) reporter mice, we show that TBI initiated a temporally restricted accumulation of peripherally derived CCR2(+) macrophages, which were concentrated in the hippocampal formation, a region necessary for learning and memory. Multivariate analysis delineated CCR2(+) macrophages' neuroinflammatory response while identifying a novel therapeutic treatment window. As a proof of concept, targeting CCR2(+) macrophages with CCX872, a novel Phase I CCR2 selective antagonist, significantly reduced TBI-induced inflammatory macrophage accumulation. Concomitantly, there was a significant reduction in multiple proinflammatory and neurotoxic mediators with this treatment paradigm. Importantly, CCR2 antagonism resulted in a sparing of TBI-induced hippocampal-dependent cognitive dysfunction and reduced proinflammatory activation profile 1 month after injury. Thus, therapeutically targeting the CCR2(+) subset of monocytes/macrophages may provide a new avenue of clinical intervention following TBI.

Cranial irradiation alters the brain's microenvironment and permits CCR2+ macrophage infiltration.

Therapeutic irradiation is commonly used to treat primary or metastatic central nervous system tumors. It is believed that activation of neuroinflammatory signaling pathways contributes to the development of common adverse effects, which may ultimately contribute to cognitive dysfunction. Recent studies identified the chemokine (C-C motif) receptor (CCR2), constitutively expressed by cells of the monocyte-macrophage lineage, as a mediator of cognitive impairments induced by irradiation. In the present study we utilized a unique reporter mouse (CCR2(RFP/+)CX3CR1(GFP/+)) to accurately delineate the resident (CX3CR1+) versus peripheral (CCR2+) innate immune response in the brain following cranial irradiation. Our results demonstrate that a single dose of 10Gy cranial γ-irradiation induced a significant decrease in the percentage of resident microglia, while inducing an increase in the infiltration of peripherally derived CCR2+ macrophages. Although reduced in percentage, there was a significant increase in F4/80+ activated macrophages in irradiated animals compared to sham. Moreover, we found that there were altered levels of pro-inflammatory cytokines, chemokines, adhesion molecules, and growth factors in the hippocampi of wild type irradiated mice as compared to sham. All of these molecules are implicated in the recruitment, adhesion, and migration of peripheral monocytes to injured tissue. Importantly, there were no measureable changes in the expression of multiple markers associated with blood-brain barrier integrity; implicating the infiltration of peripheral CCR2+ macrophages may be due to inflammatory induced chemotactic signaling. Cumulatively, these data provide evidence that therapeutic levels of cranial radiation are sufficient to alter the brain's homeostatic balance and permit the influx of peripherally-derived CCR2+ macrophages as well as the regional susceptibility of the hippocampal formation to ionizing radiation.

Characterization of a diffuse intrinsic pontine glioma cell line: implications for future investigations and treatment.

Diffuse intrinsic pontine gliomas arise almost exclusively in children, and despite advances in treatment, the majority of patients die within 2 years after initial diagnosis. Because of their infiltrative nature and anatomic location in an eloquent area of the brain, most pontine gliomas are treated without a surgical biopsy. The corresponding lack of tissue samples has resulted in a limited understanding of the underlying genetic and molecular biologic abnormalities associated with pontine gliomas, and is a substantial obstacle for the preclinical testing of targeted therapeutic agents for these tumors. We have established a human glioma cell line that originated from surgical biopsy performed on a patient with a pontine glioma. To insure sustainable in vitro propagation, tumor cells were modified with hTERT (human telomerase ribonucleoprotein reverse transcriptase), and with a luciferase reporter to enable non-invasive bioluminescence imaging. The hTERT modified cells are tumorigenic in athymic rodents, and produce brainstem tumors that recapitulate the infiltrative growth of brainstem gliomas in patients.