One-year follow-up of children hospitalized with COVID-19: a prospective cohort study.

OBJECTIVE: Currently, little is known about the long-term outcomes of COVID-19 in the pediatric population. The aim of this study was to investigate the long-term clinical outcomes of pediatric patients hospitalized with COVID-19. METHODS: This was a prospective cohort study involving unvaccinated children and adolescents admitted to a tertiary hospital in southern Brazil with a COVID-19 diagnosis. Data were collected from electronic medical records for one year after the diagnosis. RESULTS: A total of 66 children were included: the median age was 2.9 years; 63.6% were male; and 48.5% were under 2 years of age. Over 70% had at least one comorbidity prior to the COVID-19 diagnosis. During the one-year follow-up period, 59.1% of the children revisited the emergency department, 50% required readmission, and 15.2% died. Younger children with longer hospital stays were found to be at greater risk of readmission. Having cancer and impaired functionality were found to increase the risk of death within one year. CONCLUSIONS: Our findings indicate that most children hospitalized with COVID-19 have comorbidities. Younger age at admission and a longer hospital stay seem to be risk factors for readmission. In addition, the presence of cancer and impaired functionality are apparently associated with the poor outcome of death within the first year after the diagnosis of COVID-19.

Association of Intima-Media Thickness Measured at the Common Carotid Artery With Incident Carotid Plaque: Individual Participant Data Meta-Analysis of 20 Prospective Studies.

Background The association between common carotid artery intima-media thickness (CCA-IMT) and incident carotid plaque has not been characterized fully. We therefore aimed to precisely quantify the relationship between CCA-IMT and carotid plaque development. Methods and Results We undertook an individual participant data meta-analysis of 20 prospective studies from the Proof-ATHERO (Prospective Studies of Atherosclerosis) consortium that recorded baseline CCA-IMT and incident carotid plaque involving 21 494 individuals without a history of cardiovascular disease and without preexisting carotid plaque at baseline. Mean baseline age was 56 years (SD, 9 years), 55% were women, and mean baseline CCA-IMT was 0.71 mm (SD, 0.17 mm). Over a median follow-up of 5.9 years (5th-95th percentile, 1.9-19.0 years), 8278 individuals developed first-ever carotid plaque. We combined study-specific odds ratios (ORs) for incident carotid plaque using random-effects meta-analysis. Baseline CCA-IMT was approximately log-linearly associated with the odds of developing carotid plaque. The age-, sex-, and trial arm-adjusted OR for carotid plaque per SD higher baseline CCA-IMT was 1.40 (95% CI, 1.31-1.50; I2=63.9%). The corresponding OR that was further adjusted for ethnicity, smoking, diabetes, body mass index, systolic blood pressure, low- and high-density lipoprotein cholesterol, and lipid-lowering and antihypertensive medication was 1.34 (95% CI, 1.24-1.45; I2=59.4%; 14 studies; 16 297 participants; 6381 incident plaques). We observed no significant effect modification across clinically relevant subgroups. Sensitivity analysis restricted to studies defining plaque as focal thickening yielded a comparable OR (1.38 [95% CI, 1.29-1.47]; I2=57.1%; 14 studies; 17 352 participants; 6991 incident plaques). Conclusions Our large-scale individual participant data meta-analysis demonstrated that CCA-IMT is associated with the long-term risk of developing first-ever carotid plaque, independent of traditional cardiovascular risk factors.

One-year follow-up of children hospitalized with COVID-19: a prospective cohort study / Acompanhamento de um ano de crianças hospitalizadas com COVID-19: estudo prospectivo de coorte

ABSTRACT Objective: Currently, little is known about the long-term outcomes of COVID-19 in the pediatric population. The aim of this study was to investigate the long-term clinical outcomes of pediatric patients hospitalized with COVID-19. Methods: This was a prospective cohort study involving unvaccinated children and adolescents admitted to a tertiary hospital in southern Brazil with a COVID-19 diagnosis. Data were collected from electronic medical records for one year after the diagnosis. Results: A total of 66 children were included: the median age was 2.9 years; 63.6% were male; and 48.5% were under 2 years of age. Over 70% had at least one comorbidity prior to the COVID-19 diagnosis. During the one-year follow-up period, 59.1% of the children revisited the emergency department, 50% required readmission, and 15.2% died. Younger children with longer hospital stays were found to be at greater risk of readmission. Having cancer and impaired functionality were found to increase the risk of death within one year. Conclusions: Our findings indicate that most children hospitalized with COVID-19 have comorbidities. Younger age at admission and a longer hospital stay seem to be risk factors for readmission. In addition, the presence of cancer and impaired functionality are apparently associated with the poor outcome of death within the first year after the diagnosis of COVID-19.

RESUMO Objetivo: Atualmente, pouco se sabe sobre os desfechos em longo prazo da COVID-19 na população pediátrica. O objetivo deste estudo foi investigar os desfechos clínicos em longo prazo de pacientes pediátricos hospitalizados com COVID-19. Métodos: Trata-se de um estudo prospectivo de coorte com crianças e adolescentes não vacinados internados em um hospital terciário do Sul do Brasil com diagnóstico de COVID-19. Os dados referentes ao período de um ano após o diagnóstico foram extraídos dos prontuários médicos eletrônicos. Resultados: Foram incluídas 66 crianças: a mediana da idade foi de 2,9 anos; 63,6% eram do sexo masculino; 48,5% tinham menos de 2 anos de idade. Mais de 70% tinham pelo menos uma comorbidade antes do diagnóstico de COVID-19. Durante o período de um ano de acompanhamento, 59,1% das crianças retornaram ao pronto-socorro, 50% necessitaram de readmissão e 15,2% morreram. O risco de readmissão foi maior em crianças mais novas que permaneceram internadas durante mais tempo. Câncer e funcionalidade prejudicada aumentaram o risco de morte até um ano depois. Conclusões: Nossos achados indicam que a maioria das crianças hospitalizadas com COVID-19 apresenta comorbidades. Ser mais jovem no momento da internação hospitalar e permanecer internado durante mais tempo parecem ser fatores de risco de readmissão. Além disso, câncer e funcionalidade prejudicada são fatores aparentemente relacionados com o mau desfecho de óbito no primeiro ano após o diagnóstico de COVID-19.

Danger signal extracellular calcium initiates differentiation of monocytes into SPP1/osteopontin-producing macrophages.

The danger signal extracellular calcium is pathophysiologically increased in the synovial fluid of patients with rheumatoid arthritis (RA). Calcium activates the NLRP3-inflammasome via the calcium-sensing receptor in monocytes/macrophages primed by lipopolysaccharide, and this effect is mediated by the uptake of calciprotein particles (CPPs) formed out of calcium, phosphate, and fetuin-A. Aim of the study was to unravel the influence of calcium on monocytes when the priming signal is not present. Monocytes were isolated from the blood of healthy controls and RA patients. Macrophages were characterized using scRNA-seq, DNA microarray, and proteomics. Imaging flow cytometry was utilized to study intracellular events. Here we show that extracellular calcium and CPPs lead to the differentiation of monocytes into calcium-macrophages when the priming signal is absent. Additional growth factors are not needed, and differentiation is triggered by calcium-dependent CPP-uptake, lysosomal alkalization due to CPP overload, and TFEB- and STAT3-dependent increased transcription of the lysosomal gene network. Calcium-macrophages have a needle-like shape, are characterized by excessive, constitutive SPP1/osteopontin production and a strong pro-inflammatory cytokine response. Calcium-macrophages differentiated out of RA monocytes show a stronger manifestation of this phenotype, suggesting the differentiation process might lead to the pro-inflammatory macrophage response seen in the RA synovial membrane.

Functional status of hospitalized pediatric patients with COVID-19 in southern Brazil: a prospective cohort study / Estado funcional de pacientes pediátricos hospitalizados com COVID-19 no sul do Brasil: um estudo de coorte prospectivo

ABSTRACT Objective: The present study aimed to assess the functional status of children diagnosed with COVID-19 at the time of hospitalization and the associations with clinical features. Methods: This prospective cohort study was carried out with children diagnosed with COVID-19 admitted to a tertiary hospital. The patients' functioning was assessed using the pediatric Functional Status Scale (FSS). Results: A total of 62 children with a median age of 3 years old were included in the study, and 70% had some comorbidity prior to the diagnosis of COVID-19. The median length of stay was nine days, during which period five patients died. The FSS assessment of the sample showed that approximately 55% had some functional alteration. The group of patients with the highest FSS scores presented a lengthier hospital stay (p = 0.016), required more oxygen therapy (p < 0.001), mechanical ventilation (p = 0.001), and intensive care unit admissions (p = 0.019), and had more cardiac (p = 0.007), neurological (p = 0.003), and respiratory (p = 0.013) comorbidities. In the multivariate analysis, there was an association between the dependent variable length of stay and the total FSS score (b = 0.349, p = 0.004) and the presence of comorbidities (b = 0.357, p = 0.004). Conclusions: We observed that more than half of the children hospitalized due to COVID-19 had some level of functional change. Greater alterations in functional status were associated with the presence of previous comorbidities, a greater need for ventilatory support, and longer hospital stays.

RESUMO Objetivo: O objetivo do presente estudo foi de avaliar o estado funcional de crianças diagnosticadas com COVID-19 no momento da internação e as associações com suas características clínicas. Métodos: Este estudo de coorte prospectivo foi realizado com crianças diagnosticadas com COVID-19 internadas em um hospital terciário. A funcionalidade dos pacientes foi avaliada por meio da Escala de Estado Funcional (FSS) pediátrica. Resultados: Foram incluídas no estudo 62 crianças com idade mediana de 3 anos, das quais 70% apresentavam alguma comorbidade antes do diagnóstico de COVID-19. O tempo mediano de internação foi de nove dias, período no qual cinco pacientes vieram a óbito. A avaliação da FSS da amostra mostrou que aproximadamente 55% apresentavam alguma alteração funcional. O grupo de pacientes com os maiores escores na FSS teve um maior tempo de internação (p = 0,016), necessitou de mais oxigenoterapia (p < 0,001), ventilação mecânica (p = 0,001) e internações em unidade de terapia intensiva (p = 0,019) e tinha mais comorbidades cardíacas (p = 0,007), neurológicas (p = 0,003) e respiratórias (p = 0,013). Na análise multivariada, observou-se uma associação entre a variável dependente tempo de internação e o escore total da FSS (b = 0,349, p = 0,004) e a presença de comorbidades (b = 0,357, p = 0,004). Conclusões: Verificou-se que mais da metade das crianças internadas devido à COVID-19 apresentaram algum nível de alteração funcional. Maiores alterações no estado funcional foram associadas à presença de comorbidades prévias, maior necessidade de suporte ventilatório e maior tempo de internação.

PI3Kγ Mediates Microglial Proliferation and Cell Viability via ROS.

(1) Background: Rapid microglial proliferation contributes to the complex responses of the innate immune system in the brain to various neuroinflammatory stimuli. Here, we investigated the regulatory function of phosphoinositide 3-kinase γ (PI3Kγ) and reactive oxygen species (ROS) for rapid proliferation of murine microglia induced by LPS and ATP. (2) Methods: PI3Kγ knockout mice (PI3Kγ KO), mice expressing catalytically inactive PI3Kγ (PI3Kγ KD) and wild-type mice were assessed for microglial proliferation using an in vivo wound healing assay. Additionally, primary microglia derived from newborn wild-type, PI3Kγ KO and PI3Kγ KD mice were used to analyze PI3Kγ effects on proliferation and cell viability, senescence and cellular and mitochondrial ROS production; the consequences of ROS production for proliferation and cell viability after LPS or ATP stimulation were studied using genetic and pharmacologic approaches. (3) Results: Mice with a loss of lipid kinase activity showed impaired proliferation of microglia. The prerequisite of induced microglial proliferation and cell viability appeared to be PI3Kγ-mediated induction of ROS production. (4) Conclusions: The lipid kinase activity of PI3Kγ plays a crucial role for microglial proliferation and cell viability after acute inflammatory activation.

Calcium-sensing receptor-mediated NLRP3 inflammasome response to calciprotein particles drives inflammation in rheumatoid arthritis.

Increased extracellular Ca2+ concentrations ([Ca2+]ex) trigger activation of the NLRP3 inflammasome in monocytes through calcium-sensing receptor (CaSR). To prevent extraosseous calcification in vivo, the serum protein fetuin-A stabilizes calcium and phosphate into 70-100 nm-sized colloidal calciprotein particles (CPPs). Here we show that monocytes engulf CPPs via macropinocytosis, and this process is strictly dependent on CaSR signaling triggered by increases in [Ca2+]ex. Enhanced macropinocytosis of CPPs results in increased lysosomal activity, NLRP3 inflammasome activation, and IL-1ß release. Monocytes in the context of rheumatoid arthritis (RA) exhibit increased CPP uptake and IL-1ß release in response to CaSR signaling. CaSR expression in these monocytes and local [Ca2+] in afflicted joints are increased, probably contributing to this enhanced response. We propose that CaSR-mediated NLRP3 inflammasome activation contributes to inflammatory arthritis and systemic inflammation not only in RA, but possibly also in other inflammatory conditions. Inhibition of CaSR-mediated CPP uptake might be a therapeutic approach to treating RA.

Association between serum level of urate and subclinical atherosclerosis: results from the SCAPIS Pilot.

BACKGROUND: Hyperuricemia is closely associated with cardiovascular disease (CVD). However, it has not been definitively established whether this association is independent of traditional cardiovascular risk factors (CVRFs) and whether it is gender-dependent. The aim of this study was to investigate in a population-based cohort (age range, 50-64 years) stratified by sex the association between the serum urate (SU) concentration and subclinical atherosclerosis, as reflected in the coronary artery calcification (CAC) score, common carotid intima-media thickness (CIMT), and carotid plaque score. METHODS: The study involved participants in the Swedish CArdioPulmonary bioImage Study (SCAPIS) Pilot cohort (N = 1040; 48.8% males). This pilot cohort is part of the large population-based SCAPIS with 30,000 participants in the age range of 50-64 years, aimed at improving risk prediction for CVD. Subjects with a self-reported previous history of CVD (N = 68) or gout (N = 3) were excluded. The CAC score was assessed with the Agatston method using computed tomography. CIMT and carotid plaques were quantified by ultrasound. The associations between the SU quartiles and different levels of CAC, CIMT, and carotid plaques were assessed by multivariable logistic regression. RESULTS: Age, BMI, education level, smoking, physical activity, hs-CRP, hypertension, and dyslipidemia showed no differences between males and females, while CAC (score > 0) and diabetes were both twice as common in men than in women (58% vs 26% and 8% vs 4%, respectively). Higher SU quartiles were in both sexes associated with BMI, hs-CRP, and the prevalence of hypertension, and in women, they were also associated with the prevalence of dyslipidemia. The three upper quartiles of SU (>308µmol/L) were linked to higher CAC scores in men, when adjusting for CVRFs, but not in women. CIMT and carotid plaques showed no correlation to SU in either sex. CONCLUSIONS: Higher levels of SU are associated with the presence of CAC in men but not in women, whereas SU is not associated with CIMT or carotid plaques in either men or women. This implies that the biological effects of SU differ in men and women or that SU has varying effects on different vascular beds or during the different stages of the atherosclerotic process.

Photochemistry of iron in aquatic environments.

Light energy is a driver for many biogeochemical element cycles in aquatic systems. The sunlight-induced photochemical reduction of ferric iron (Fe(iii) photoreduction) to ferrous iron (Fe(ii)) by either direct ligand-to-metal charge transfer or by photochemically produced radicals can be an important source of dissolved Feaq2+ in aqueous and sedimentary environments. Reactive oxygen species (ROS) are formed by a variety of light-dependent reactions. Those ROS can oxidize Fe(ii) or reduce Fe(iii), and due to their high reactivity they are key oxidants in aquatic systems where they influence many other biogeochemical cycles. In oxic waters with circumneutral pH, the produced Fe(ii) reaches nanomolar concentrations and serves as a nutrient, whereas in acidic waters, freshwater and marine sediments, which are rich in Fe(ii), the photochemically formed Fe(ii) can reach concentrations of up to 100 micromolar and be used as additional electron donor for acidophilic aerobic, microaerophilic, phototrophic and, if nitrate is present, for nitrate-reducing Fe(ii)-oxidizing bacteria. Therefore, Fe(iii) photoreduction may not only control the primary productivity in the oceans but has a tremendous impact on Fe cycling in the littoral zone of freshwater and marine environments. In this review, we summarize photochemical reactions involving Fe, discuss the role of ROS in Fe cycling, and highlight the importance of photoreductive processes in the environment.

Contribution of Microaerophilic Iron(II)-Oxidizers to Iron(III) Mineral Formation.

Neutrophilic microbial aerobic oxidation of ferrous iron (Fe(II)) is restricted to pH-circumneutral environments characterized by low oxygen where microaerophilic Fe(II)-oxidizing microorganisms successfully compete with abiotic Fe(II) oxidation. However, accumulation of ferric (bio)minerals increases competition by stimulating abiotic surface-catalyzed heterogeneous Fe(II) oxidation. Here, we present an experimental approach that allows quantification of microbial and abiotic contribution to Fe(II) oxidation in the presence or initial absence of ferric (bio)minerals. We found that at 20 µM O2 and the initial absence of Fe(III) minerals, an iron(II)-oxidizing enrichment culture (99.6% similarity to Sideroxydans spp.) contributed 40% to the overall Fe(II) oxidation within approximately 26 h and oxidized up to 3.6 × 10-15 mol Fe(II) cell-1 h-1. Optimum O2 concentrations at which enzymatic Fe(II) oxidation can compete with abiotic Fe(II) oxidation ranged from 5 to 20 µM. Lower O2 levels limited biotic Fe(II) oxidation, while at higher O2 levels abiotic Fe(II) oxidation dominated. The presence of ferric (bio)minerals induced surface-catalytic heterogeneous abiotic Fe(II) oxidation and reduced the microbial contribution to Fe(II) oxidation from 40% to 10% at 10 µM O2. The obtained results will help to better assess the impact of microaerophilic Fe(II) oxidation on the biogeochemical iron cycle in a variety of environmental natural and anthropogenic settings.

Inverse association between size of the lipid-rich necrotic core and vascularization in human carotid plaques.

PURPOSE: To study the relationship between the size of the lipid-rich necrotic core measured by MRI (magnetic resonance imaging) and the level of plaque vascularization measured by contrast-enhanced ultrasound, in human carotid plaques. Further, to compare the size of lipid-rich necrotic core from MRI to plaque echogenicity. METHODS: Thirty-one subjects with carotid plaques underwent standard B-mode ultrasound, contrast-enhanced ultrasound and MRI. The lipid-rich necrotic core was quantified using MRI. Contrast-enhanced ultrasound was used to measure carotid plaque vascularization. Standard B-mode ultrasound was used to measure plaque echogenicity as greyscale median. RESULTS: The amount of lipid-rich necrotic core correlated inversely with the degree of plaque vascularization (r = -0·40, P = 0·03). There were no correlations between the degree of plaque vascularization and the amount of fibrous tissue or calcifications. There were no correlations between greyscale median and the lipid-rich necrotic core, fibrous tissue or calcifications. CONCLUSIONS: We show that more dense plaque vascularization is associated with a lower plaque content of lipid-rich necrotic core. A large lipid-rich necrotic core and high plaque vascularization are both proposed as predictors of vulnerability, and our finding is therefore odds with some earlier observations. Our finding can be explained by the fact that the necrotic core of the plaque contains no viable tissue and therefore less of the plaque can be vascularized if the lipid-rich necrotic core is large. Our study suggests that the true relation between plaque vascularization and other indices of vulnerability is more complex than initially thought.

Genetic variants of TRAF6 modulate peritoneal immunity and the risk of spontaneous bacterial peritonitis in cirrhosis: A combined prospective-retrospective study.

Alterations of the innate immunity contribute to the development of spontaneous bacterial peritonitis (SBP) in liver cirrhosis. Given its role in immune signaling, antimicrobial function, and macrophage differentiation, we hypothesized that genetic polymorphisms of TRAF6 modulate the risk of SBP. Thus, we determined theTRAF6 haplotype in 432 patients with cirrhosis and ascites using the haplotype-tagging single nucleotide polymorphisms rs331457 and rs5030419. In addition, peritoneal macrophages were immunomagnetically isolated and characterized. Overall, 122 (28%) patients had an episode of SBP. In the combined prospective-retrospective analysis the frequency of SBP differed between the four haplotypes (P = 0.014) and was the highest in 102 patients carrying the rs331457 but not the rs5030419 variant, when compared to other haplotypes (odds ratio 1.95 [1.22-3.12]) or to the wild-type (odds ratio 1.71 [1.04-2.82]). This association was confirmed in multivariate logistic regression (adjusted odds ratio 2.00 [1.24-3.22]) and in prospective sensitivity analysis (hazard ratio 2.09 [1.08-4.07]; P = 0.03). The risk haplotype was associated with lower concentrations of the immune activation marker soluble CD87 in ascitic fluid and with a decreased expression of IL-6 and CXCL8 in isolated peritoneal macrophages. In conclusion, genetic polymorphisms of TRAF6 are associated with decreased peritoneal immune activation and an increased risk of SBP.

Endogenous Retrovirus 3 - History, Physiology, and Pathology.

Endogenous viral elements (EVE) seem to be present in all eukaryotic genomes. The composition of EVE varies between different species. The endogenous retrovirus 3 (ERV3) is one of these elements that is present only in humans and other Catarrhini. Conservation of ERV3 in most of the investigated Catarrhini and the expression pattern in normal tissues suggest a putative physiological role of ERV3. On the other hand, ERV3 has been implicated in the pathogenesis of auto-immunity and cancer. In the present review we summarize knowledge about this interesting EVE. We propose the model that expression of ERV3 (and probably other EVE loci) under pathological conditions might be part of a metazoan SOS response.

Phagocytosis of bone marrow derived macrophages is controlled by phosphoinositide 3-kinase γ.

Due to their ability to phagocytise invading microbes macrophages play a key role in the innate and acquired immune system. In this article the role of phosphoinositide 3-kinase gamma (PI3Kγ) for phagocytosis was studied in bone marrow derived macrophages (BMDM). By using genetic and pharmacological approaches our data clearly demonstrate PI3Kγ is acting as a mediator of macrophage phagocytosis. Phagocytosis of LPS activated BMDM was reduced in PI3Kγ depleted primary BMDM or macrophage cell line J774. Depletion of other class I phosphoinositide 3-kinases did not alter phagocytic activity. Partial reduction of the phagocytic index of BMDM expressing kinase inactive PI3Kγ indicate a lipid-kinase independent role of the PI3Kγ protein. Since inhibition of PI3Kγ interaction partner phosphodiesterase PDE3B reduced BMDM phagocytosis and PI3Kγ knock out super stimulated cAMP level, our data reveal that PI3Kγ protein mediated suppression of cAMP signalling is a critical for efficient phagocytosis of macrophages.

Indications and outcomes of resident-performed cataract surgery requiring return to the operating room.

PURPOSE: To identify the clinical and operative factors predicting reoperation within 30 days of resident-performed cataract surgery and correlate them with 1-year visual outcomes. SETTING: Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas, USA. DESIGN: Retrospective cohort study. METHODS: The study assessed patients who had resident-performed cataract surgery between 2005 and 2013 and required return to the operating room for a second surgery on the same eye within 30 days. Preoperative and intraoperative risk factors were assessed. Outcome measures included corrected distance visual acuity (CDVA) at 1 year. RESULTS: A review of 6644 resident-performed cataract surgeries showed that 54 eyes (0.85%) of 54 patients required a return to the operating room within 30 days. The reoperation rate was higher in the first half of the academic year (1.18%) than in the second half (0.55%) (P = .004). The mean CDVA 1 year postoperatively was 20/40, with a loss of lines of vision in 4 eyes. The mean operative time was 59.23 minutes ± 35.05 (SD). A longer intraoperative time was predictive of a worse visual outcome (P < .01). CONCLUSIONS: Despite the need for reoperation within 30 days, most patients achieved improved visual acuity. The reoperation rate was significantly lower in the second half of the academic year. Increased operation times correlated with worse visual acuity independent of other variables.

Phosphoinositide 3-Kinase γ Restrains Neurotoxic Effects of Microglia After Focal Brain Ischemia.

Phosphoinositide 3-kinase γ (PI3Kγ) is linked to neuroinflammation and phagocytosis. This study was conducted to elucidate conjectural differences of lipid kinase-dependent and kinase-independent functions of PI3Kγ in the evolvement of brain damage induced by focal cerebral ischemia/reperfusion. Therefore, PI3Kγ wild-type, knockout, and kinase-dead mice were subjected to middle cerebral artery occlusion followed by reperfusion. Tissue damage and cellular composition were assessed by immunohistochemical stainings. In addition, microglial cells derived from respective mouse genotypes were used for analysis of PI3Kγ effects on phagocytic activity, matrix metalloproteinase-9 release, and cAMP content under conditions of oxygen/glucose deprivation and recovery. Brain infarction was more pronounced in PI3Kγ-knockout mice compared to wild-type and kinase-dead mice 48 h after reperfusion. Immunohistochemical analyses revealed a reduced amount of galectin-3/MAC-2-positive microglial cells indicating that activated phagocytosis was reduced in ischemic brains of knockout mice. Cell culture studies disclosed enhanced metalloproteinase-9 secretion in supernatants derived from microglia of PI3Kγ-deficient mice after 2-h oxygen/glucose deprivation and 48-h recovery. Furthermore, PI3Kγ-deficient microglial cells showed a failed phagocytic activation throughout the observed recovery period. Lastly, PI3Kγ-deficient microglia exhibited strongly increased cAMP levels in comparison with wild-type microglia or cells expressing kinase-dead PI3Kγ after oxygen/glucose deprivation and recovery. Our data suggest PI3Kγ kinase activity-independent control of cAMP phosphodiesterase as a crucial mediator of microglial cAMP regulation, MMP-9 expression, and phagocytic activity following focal brain ischemia/recirculation. The suppressive effect of PI3Kγ on cAMP levels appears critical for the restriction of ischemia-induced immune cell functions and in turn tissue damage.

Phosphoinositide 3-kinase γ affects LPS-induced disturbance of blood-brain barrier via lipid kinase-independent control of cAMP in microglial cells.

The breakdown of the blood-brain barrier (BBB) is a key event in the development of sepsis-induced brain damage. BBB opening allows blood-born immune cells to enter the CNS to provoke a neuroinflammatory response. Abnormal expression and activation of matrix metalloproteinases (MMP) was shown to contribute to BBB opening. Using different mouse genotypes in a model of LPS-induced systemic inflammation, our present report reveals phosphoinositide 3-kinase γ (PI3Kγ) as a mediator of BBB deterioration and concomitant generation of MMP by microglia. Unexpectedly, microglia expressing lipid kinase-deficient mutant PI3Kγ exhibited similar MMP regulation as wild-type cells. Our data suggest kinase-independent control of cAMP phosphodiesterase activity by PI3Kγ as a crucial mediator of microglial cell activation, MMP expression and subsequent BBB deterioration. The results identify the suppressive effect of PI3Kγ on cAMP as a critical mediator of immune cell functions.

Rivaroxaban postmarketing risk of liver injury.

BACKGROUND & AIMS: Rivaroxaban is an oral direct factor Xa inhibitor that has been marketed worldwide since 2008 for the primary and secondary prevention and treatment of thromboembolic disorders. Although liver injury was observed in premarketing trials of rivaroxaban, there are no published postmarketing cases of liver injury associated with rivaroxaban. METHODS: Report of 14 cases of liver injury associated with rivaroxaban, including two with liver biopsy, and search queries in three large international pharmacovigilance databases for comparable cases. RESULTS: Formal causality assessment classified rivaroxaban as the "highly probable", "probable", and "possible" cause in 4, 7, and 3 patients, respectively. Search results from three large international pharmacovigilance databases revealed a considerable number of additional hepatic adverse events where rivaroxaban was reported as a suspected cause. CONCLUSIONS: We interpret the presented information as a relevant safety signal that should be followed by pharmacoepidemiological studies in order to reliably estimate absolute and relative risks of liver injury associated with rivaroxaban in support of rational risk-benefit assessment. Meanwhile, incident symptoms and signs of liver disease in patients treated with rivaroxaban should be considered as a potential adverse drug reaction, and if no other likely cause can be identified rivaroxaban should be stopped as soon as possible.

The metabolic syndrome predicts cardiovascular events: results of a 13-year follow-up in initially healthy 58-year-old men.

BACKGROUND: The metabolic syndrome is a global health problem and is associated with subsequent development of cardiovascular disease (CVD). However, data are scarce concerning prospective association of the syndrome and CVD in populations free of diabetes and previous CVD that also is free of all cardiovascular drugs. The aim of this study was to assess the risk of cardiovascular events due to the metabolic syndrome in a population-based cohort of initially healthy, low-risk, and medication-free 58-year-old Swedish men during 13-years of follow-up. METHODS: From a total population sample of 1728 subjects, a stratified and randomly selected group of 391 subjects was included. The metabolic syndrome was defined according to the National Cholesterol Education Program. Cardiovascular events and cause of death were investigated by contact with the Centre of Epidemiology at the National Board of Health and Welfare. RESULTS: The metabolic syndrome increased the risk of cardiovascular events with a hazard ratio of 2.1 [95% confidence interval (CI) 1.3-3.4], P=0.003. When adjusted for the factors of leisure-time physical activity, smoking habits, alcohol intake, and low-density lipoprotein cholesterol (LDL-C), the hazard ratio was 2.0 (95% CI 1.1-3.4), P=0.016. CONCLUSION: In a 13-year follow-up in initially healthy men, the metabolic syndrome increases the risk of cardiovascular events by two-fold. This risk was maintained also after adjustment for lifestyle factors.