Invasive Strategy in Octogenarians with Non-ST-Segment Elevation Acute Myocardial Infarction.

With population aging and the subsequent accumulation of cardiovascular risk factors, a growing proportion of patients presenting with acute coronary syndrome (ACS) are octogenarian (aged between 80 and 89). The marked heterogeneity of this population is due to several factors like age, comorbidities, frailty, and other geriatric conditions. All these variables have a strong impact on outcomes. In addition, a high prevalence of multivessel disease, complex coronary anatomies, and peripheral arterial disease, increases the risk of invasive procedures in these patients. In advanced age, the type and duration of antithrombotic therapy need to be individualized according to bleeding risk. Although an invasive strategy for non-ST-segment elevation acute myocardial infarction (NSTEMI) is recommended for the general population, its need is not so clear in octogenarians. For instance, although frail patients could benefit from revascularization, their higher risk of complications might change the risk/benefit ratio. Age alone should not be the main factor to consider when deciding the type of strategy. The risk of futility needs to be taken into account and identification of risk factors for adverse outcomes, such as renal impairment, could help in the decision-making process. Finally, an initially selected conservative strategy should be open to a change to invasive management depending on the clinical course (recurrent angina, ventricular arrhythmias, heart failure). Further evidence, ideally from prospective randomized clinical trials is urgent, as the population keeps growing.

Use of social media in radiation oncology: multicenter data from the GOCO Group.

Background: The purpose of this study was to explore the usage patterns and profiles of social media (SM) platforms among Radiation Oncologists (RO) and Physicists in the scope of the Catalan-Occitan Oncology Group (GOCO). Materials and methods: From November 2022 to March 2023, a comprehensive survey was sent to Radiation Oncology professionals within the GOCO group, comprising 31 questions that covered demographics (4) and general inquiries (9), user behavior on social media (7), profile of SM activity (7), and participants' opinions (4) regarding professional use of SM. The survey reached professionals from 12 centers, encompassing 10 in Catalonia and 2 in French Occitania. Results: The survey achieved a 61.37% response rate (178/290 professionals) with an average age of 41.9 years. 120 (67%) were ROs, and 58 (33%) were Physicists. Instagram led in usage (n = 116), followed by Facebook (n = 107) and Twitter (n = 77). Age correlated inversely with the number of platforms used (Spearman's rank correlation coefficient -0.238, p = 0.001). 28% (n = 42) changed clinical practices based on SM information. A 78.5% (n = 117) didn't counter inappropriate content. Most (71.7%, n = 109) spent < 1 hour daily on professional SM use, however more Physicians exceeded 2 hours compared to Physicists (Cohen's kappa 2 = 0.07). 41.8% (n = 64) weren't emotionally concerned while 22.9% (n = 35) felt overwhelmed by SM overload. Conclusions: The study offers valuable insights into the usage patterns, preferences, and attitudes of Radiation Oncology professionals towards SM platforms. This understanding is crucial for optimizing content quality and delivering relevant information, thereby enabling more effective marketing strategies and enhancing emotional management among these professionals.

A cross-sectional study on stool- and gastrointestinal-related outcomes of Mexican infants consuming different formulae.

BACKGROUND: Immaturities present at birth, such as in the gut microbiome and digestive, nervous, and immune system, resolve with time. Nevertheless, this may result in mild digestive symptoms early in life, particularly in formula-fed infants. Formula composition and processing may impact this discomfort. This study therefore aimed to assess stool characteristics and gastrointestinal symptoms of healthy infants fed different formulae. METHODS: A multicenter, cross-sectional, observational trial was performed in Mexico between November 2019 and January 2022, where exclusively formula-fed infants (n = 342, aged 1-4 months) were studied in four groups based on their existing formula use. Feeding was continued per practice following label instructions. For 7 days, parents/caregivers were requested to record fecal characteristics, using the Amsterdam Infant Stool Scale, and rate gastrointestinal symptoms. Stool samples were collected to determine pH, dry matter content, and fecal calprotectin levels. RESULTS: Most infants had a soft/formed stool consistency, although odds for hard stools were different between groups. Gastrointestinal symptom scores revealed significant differences for burping and diarrhea, while other symptoms did not differ between groups. No significant differences between groups were found for stool frequency, dry matter content, and fecal pH. Although calprotectin was within the expected healthy ranges, significant differences among groups were seen. Furthermore, calprotectin significantly correlated with the severity of the gastrointestinal symptoms burping, flatulence, abdominal distension, and diarrhea. CONCLUSIONS: Differences in stool characteristics and specific differences in gastrointestinal symptoms were observed between different formula brand users. This may potentially be explained by the different composition and processing of the formulae, although there are multiple factors that influence the assessed outcomes. TRIAL REGISTRATION: The study was registered in the Netherlands Trial Registry (NL7805), linked to https://trialsearch.who.int/ , on 11/06/2019.

A family study implicates GBE1 in the etiology of autism spectrum disorder.

Autism spectrum disorders (ASD) are neurodevelopmental disorders with an estimated heritability of >60%. Family-based genetic studies of ASD have generally focused on multiple small kindreds, searching for de novo variants of major effect. We hypothesized that molecular genetic analysis of large multiplex families would enable the identification of variants of milder effects. We studied a large multigenerational family of European ancestry with multiple family members affected with ASD or the broader autism phenotype (BAP). We identified a rare heterozygous variant in the gene encoding 1,4-ɑ-glucan branching enzyme 1 (GBE1) that was present in seven of seven individuals with ASD, nine of ten individuals with the BAP, and none of four tested unaffected individuals. We genotyped a community-acquired cohort of 389 individuals with ASD and identified three additional probands. Cascade analysis demonstrated that the variant was present in 11 of 13 individuals with familial ASD/BAP and neither of the two tested unaffected individuals in these three families, also of European ancestry. The variant was not enriched in the combined UK10K ASD cohorts of European ancestry but heterozygous GBE1 deletion was overrepresented in large ASD cohorts, collectively suggesting an association between GBE1 and ASD.

Prolactin Reduces Hippocampal Parvalbumin and GABAA Receptor Expression in Female Mice.

INTRODUCTION: Parvalbumin (PV)-positive cells are strategic elements of neuronal networks capable of influencing memory and learning processes. However, it is not known whether pituitary hormones may be related to PV expression in the hippocampus - a part of the limbic system with important functions in learning and memory. OBJECTIVE: Since previous studies indicate that prolactin (PRL) plays a significant role in hippocampal-dependent learning and synaptic plasticity, we hypothesized that a rise in PRL levels can modify PV expression in the hippocampus. METHODS: We employed biochemical, immunohistochemistry, and densitometry techniques - as well as a behavioural assay - in a hyperprolactinemia model using subcutaneous osmotic pumps in female mice. RESULTS: PRL treatment via osmotic pump induced an increase in PRL receptor (PRLR) expression in most regions of the hippocampus analysed by Western blotting and immunohistochemistry methods. Fluorescent densitometry analysis revealed that PV expression decreases in the same layers in the hippocampus following PRL treatment, while double labelling immunostaining indicated close localization of PV and PRLR in PV-positive interneurons. In addition, we found that PRL induced a reduction in the ß2/3 subunit of GABAA receptor (GABAAR) expression that was linearly correlated with the reduction in PV expression. This reduction in the ß2/3 subunit of GABAAR expression was maintained in trained animals in which PRL treatment improved the learning of a spatial memory task. CONCLUSIONS: These data show, for the first time, that an increase in PRL level is associated with changes in key constituent elements of inhibitory circuits in the hippocampus and may be of relevance for the alterations in cognitive function reported in hyperprolactinemia.

The use of two Comfort Young Child Formulas in the dietary management of toddlers with functional constipation: a randomized controlled trial.

BACKGROUND: Pharmacological intervention with laxatives is the conventional treatment for functional constipation (FC). Data to support the dietary management of FC is lacking. This study compared the efficacy of two Comfort young child formulas (YCFs) with regards to the maintenance of healthy stooling parameters in toddlers with a history of constipation. It was registered in the Netherlands Trial Registry [identifier: NL7420 (NTR7653)], registration date 20/09/2018. METHODS: Ninety-five healthy toddlers, aged 12 to 32 months, diagnosed with FC (Rome III criteria) were randomized to receive one of two study formulas after pharmacological treatment. For the first month of the intervention, subjects received a laxative in a decreasing maintenance dose alongside a test or control formula (maintenance phase). Subsequently, subjects only consumed formula for another month (post-maintenance phase). Stooling parameters were obtained weekly using the Bristol Stool Scale and the modified Rome III Questionnaire on Paediatric Gastrointestinal Symptoms for infants and toddlers. Differences in percentages of hard stools (primary outcome) and other stooling parameters were analysed using analysis of covariance and Chi-Square methods. RESULTS: Both formulas resulted in similar overall percentage of hard stools during the intervention period, respectively 5.02% in the test and 2.99% in the control group (n.s.). In the test group, percentages dropped from 7.11% at the end of the maintenance phase, to 3.92% at the end of the post-maintenance phase. In contrast, the percentage of hard stools in the control group was similar at the end of the maintenance (3.18%) and post-maintenance phase (2.83%; n.s.). No difference was found in the overall stool frequency between groups. At the end of the maintenance phase, only 22% and 19% of toddlers consuming the test and control formulae, respectively, met 2 or more of the criteria for FC. At the end of the study, this percentage of subjects decreased further to 9% in the test group, which tended to be lower compared to the 21% found in the control (p = 0.107). No laxative use was reported in either study group during the post-maintenance phase. CONCLUSION: Both Comfort YCF support the maintenance of improved stooling over time in toddlers with a history of constipation. The percentage of subjects suffering from functional constipation tended to be lower after the intervention period when receiving the formula with intact protein.

GSK3ß Inhibition by Phosphorylation at Ser389 Controls Neuroinflammation.

The inhibition of Glycogen Synthase Kinase 3 ß (GSK3ß) by Ser9 phosphorylation affects many physiological processes, including the immune response. However, the consequences of GSK3ß inhibition by alternative Ser389 phosphorylation remain poorly characterized. Here we have examined neuroinflammation in GSK3ß Ser389 knock-in (KI) mice, in which the phosphorylation of Ser389 GSK3ß is impaired. The number of activated microglia/infiltrated macrophages, astrocytes, and infiltrated neutrophils was significantly higher in these animals compared to C57BL/6J wild-type (WT) counterparts, which suggests that the failure to inactivate GSK3ß by Ser389 phosphorylation results in sustained low-grade neuroinflammation. Moreover, glial cell activation and brain infiltration of immune cells in response to lipopolysaccharide (LPS) failed in GSK3ß Ser389 KI mice. Such effects were brain-specific, as peripheral immunity was not similarly affected. Additionally, phosphorylation of the IkB kinase complex (IKK) in response to LPS failed in GSK3ß Ser389 KI mice, while STAT3 phosphorylation was fully conserved, suggesting that the NF-κB signaling pathway is specifically affected by this GSK3ß regulatory pathway. Overall, our findings indicate that GSK3ß inactivation by Ser389 phosphorylation controls the brain inflammatory response, raising the need to evaluate its role in the progression of neuroinflammatory pathologies.

An Exploration of the Psychometric Properties of the PASS-20 in Older Adults with Chronic Pain: Preliminary Development and Validity.

OBJECTIVES: The Pain Anxiety Symptoms Scale (PASS-20) is well validated in adults and younger populations, but not in older adults. This study aimed to analyze the psychometric properties of the PASS-20 in Spanish older adults who experience chronic pain. METHODS: Participants were 111 older adults with chronic pain living in nursing homes (mean age = 83.36; SD = 6.53; 78.6% female). Face-to-face interviews were conducted which included assessment of pain anxiety (PASS-20), chronic pain acceptance (CPAQ), depression symptoms (GDS), catastrophizing beliefs (PCS), pain severity, and sociodemographic information. An Exploratory Structural Equation Modeling (ESEM) approach was used to refine the scale. RESULTS: The final scale was composed of seven items, measuring two factors that could be labeled "Internal experiences" and "Escape/Avoidance behaviors". The two factors explained 60.98% of the total variance. PASS-7 version fit properly: χ2/df = 14.57/13, CMIN/df = 1.121, CFI = 0.99, RMSEA = 0.033, TLI = 0.98, GFI = 0.96, AGFI = 0.92. Good validity indices were found and acceptable reliability results in the scale and its subscales (Chronbach´s α; Internal Experiences = 0.70; Escape/Avoidance Behaviors= 0.73; Total Scale = 0.77). CONCLUSIONS: The short version of the PASS-7 has good psychometric properties. CLINICAL IMPLICATIONS: The brevity of the PASS-7 increases the feasibility of this instrument which could potentially be utilized in a variety of clinical settings and research studies with older people with chronic pain samples, specially institutionalized older adults.

Quality of life in patients with breakthrough cancer pain in radiation oncology departments in Spain: the CAVIDIOR study.

Aim: The CAVIDIOR study evaluated quality of life (QoL) in patients with breakthrough cancer pain receiving palliative radiation therapy in radiation oncology departments (RODs) in Spain. Patients & methods: Prospective observational study at 11 Spanish RODs (July 2016-November 2017). QoL was assessed using Short Form Health Survey 12. Secondary end points were sleep quality, caregiver burden and patient/perception of improvement. Results: QoL improved according to the Short Form Health Survey 12 mental component. Sleep quality and caregivers' burden improved significantly. Conclusion: Breakthrough cancer pain is highly prevalent and can be substantially reduced with appropriate diagnosis and management in RODs. Along with the QoL questionnaire, sleep quality and caregiver burden provide a more comprehensive assessment of overall health status in patients receiving radiation therapy in RODs. Clinical trial registration: NCT02836379 (ClinicalTrials.gov).

Cerebral hypomyelination associated with biallelic variants of FIG4.

The lipid phosphatase gene FIG4 is responsible for Yunis-Varón syndrome and Charcot-Marie-Tooth disease Type 4J, a peripheral neuropathy. We now describe four families with FIG4 variants and prominent abnormalities of central nervous system (CNS) white matter (leukoencephalopathy), with onset in early childhood, ranging from severe hypomyelination to mild undermyelination, in addition to peripheral neuropathy. Affected individuals inherited biallelic FIG4 variants from heterozygous parents. Cultured fibroblasts exhibit enlarged vacuoles characteristic of FIG4 dysfunction. Two unrelated families segregate the same G > A variant in the +1 position of intron 21 in the homozygous state in one family and compound heterozygous in the other. This mutation in the splice donor site of exon 21 results in read-through from exon 20 into intron 20 and truncation of the final 115 C-terminal amino acids of FIG4, with retention of partial function. The observed CNS white matter disorder in these families is consistent with the myelination defects in the FIG4 null mouse and the known role of FIG4 in oligodendrocyte maturation. The families described here the expanded clinical spectrum of FIG4 deficiency to include leukoencephalopathy.

Cardiovascular Responses of Women with Fibromyalgia to a Laboratory Stressor: Does Post-traumatic Stress Disorder Comorbidity Matter?

OBJECTIVES: This study compared cardiovascular responses to a laboratory trauma-unrelated stressor of two groups of women diagnosed with fibromyalgia (FM), one of them with comorbid post-traumatic stress disorder (PTSD), with a group of healthy controls in order to detect the possible existence of differences linked to comorbidity. DESIGN: Case-controls. METHODS: Eighteen women diagnosed with FM and comorbid PTSD, 18 women diagnosed with FM and no PTSD, and 38 healthy women were exposed to an arithmetic task with harassment while blood pressure and heart rate were measured during task exposure and recovery. RESULTS: Although heart rate response evidenced a general blunted reactivity for both groups of FM patients, only those with comorbid PTSD presented lower levels of reactivity in terms of their systolic blood pressure response. In addition, systolic blood pressure response was sensitive to the presence of depression in both groups of FM patients and controls. Finally, although both groups of FM patients showed significantly slower rates of recovery, their final recovery state was not worse after twelve minutes of recording. CONCLUSIONS: Results of this study point to comorbid PTSD as a significant contributor to the blunted cardiovascular reactivity observed in FM patients, which may be dependent to a great extent on depressive symptomatology. As some degree of cardiovascular response to stress is functional in that it mobilizes energy and triggers the necessary compensatory mechanisms to manage stressors, this study supports the well-recognized clinical strategies of detection and treatment of PTSD and concomitant depression in the management of FM.

Usefulness of a Dual Macro- and Micro-Energy-Dispersive X-Ray Fluorescence Spectrometer to Develop Quantitative Methodologies for Historic Mortar and Related Materials Characterization.

Wavelength dispersive X-ray fluorescence (WD-XRF) spectrometry has been widely used for elemental quantification of mortars and cements. In this kind of instrument, samples are usually prepared as pellets or fused beads and the whole volume of sample is measured at once. In this work, the usefulness of a dual energy dispersive X-ray fluorescence spectrometer (ED-XRF), working at two lateral resolutions (1 mm and 25 µm) for macro and microanalysis respectively, to develop quantitative methods for the elemental characterization of mortars and concretes is demonstrated. A crucial step before developing any quantitative method with this kind of spectrometers is to verify the homogeneity of the standards at these two lateral resolutions. This new ED-XRF quantitative method also demonstrated the importance of matrix effects in the accuracy of the results being necessary to use Certified Reference Materials as standards. The results obtained with the ED-XRF quantitative method were compared with the ones obtained with two WD-XRF quantitative methods employing two different sample preparation strategies (pellets and fused beads). The selected ED-XRF and both WD-XRF quantitative methods were applied to the analysis of real mortars. The accuracy of the ED-XRF results turn out to be similar to the one achieved by WD-XRF, except for the lightest elements (Na and Mg). The results described in this work proved that µ-ED-XRF spectrometers can be used not only for acquiring high resolution elemental map distributions, but also to perform accurate quantitative studies avoiding the use of more sophisticated WD-XRF systems or the acid extraction/alkaline fusion required as destructive pretreatment in Inductively coupled plasma mass spectrometry based procedures.

Absence of Notch1 in murine myeloid cells attenuates the development of experimental autoimmune encephalomyelitis by affecting Th1 and Th17 priming.

Inhibition of Notch signalling in T cells attenuates the development of experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. Growing evidence indicates that myeloid cells are also key players in autoimmune processes. Thus, the present study evaluates the role of the Notch1 receptor in myeloid cells on the progression of myelin oligodendrocyte glycoprotein (MOG)35-55 -induced EAE, using mice with a myeloid-specific deletion of the Notch1 gene (MyeNotch1KO). We found that EAE progression was less severe in the absence of Notch1 in myeloid cells. Thus, histopathological analysis revealed reduced pathology in the spinal cord of MyeNotch1KO mice, with decreased microglia/astrocyte activation, demyelination and infiltration of CD4+ T cells. Moreover, these mice showed lower Th1 and Th17 cell infiltration and expression of IFN-γ and IL-17 mRNA in the spinal cord. Accordingly, splenocytes from MyeNotch1KO mice reactivated in vitro presented reduced Th1 and Th17 activation, and lower expression of IL-12, IL-23, TNF-α, IL-6, and CD86. Moreover, reactivated wild-type splenocytes showed increased Notch1 expression, arguing for a specific involvement of this receptor in autoimmune T cell activation in secondary lymphoid tissues. In summary, our results reveal a key role of the Notch1 receptor in myeloid cells for the initiation and progression of EAE.

Ticagrelor versus clopidogrel for recovery of vascular function immediately after successful chronic coronary total occlusion recanalization: A randomized clinical trial.

Coronary vascular function of a chronic coronary total occlusion (CTO) immediately after recanalization is known to be poor. We sought if ticagrelor may augment adenosine-induced coronary blood flow vs. clopidogrel immediately after successful CTO percutaneous coronary intervention (PCI).

Meeting the challenges of implementing rapid genomic testing in acute pediatric care.

PURPOSE: The purpose of the study was to implement and prospectively evaluate the outcomes of a rapid genomic diagnosis program at two pediatric tertiary centers. METHODS: Rapid singleton whole-exome sequencing (rWES) was performed in acutely unwell pediatric patients with suspected monogenic disorders. Laboratory and clinical barriers to implementation were addressed through continuous multidisciplinary review of process parameters. Diagnostic and clinical utility and cost-effectiveness of rWES were assessed. RESULTS: Of 40 enrolled patients, 21 (52.5%) received a diagnosis, with median time to report of 16 days (range 9-109 days). A result was provided during the first hospital admission in 28 of 36 inpatients (78%). Clinical management changed in 12 of the 21 diagnosed patients (57%), including the provision of lifesaving treatment, avoidance of invasive biopsies, and palliative care guidance. The cost per diagnosis was AU$13,388 (US$10,453). Additional cost savings from avoidance of planned tests and procedures and reduced length of stay are estimated to be around AU$543,178 (US$424,101). The clear relative advantage of rWES, joint clinical and laboratory leadership, and the creation of a multidisciplinary "rapid team" were key to successful implementation. CONCLUSION: Rapid genomic testing in acute pediatrics is not only feasible but also cost-effective, and has high diagnostic and clinical utility. It requires a whole-of-system approach for successful implementation.

Addressing Criticisms of Large-Scale Marine Protected Areas.

Designated large-scale marine protected areas (LSMPAs, 100,000 or more square kilometers) constitute over two-thirds of the approximately 6.6% of the ocean and approximately 14.5% of the exclusive economic zones within marine protected areas. Although LSMPAs have received support among scientists and conservation bodies for wilderness protection, regional ecological connectivity, and improving resilience to climate change, there are also concerns. We identified 10 common criticisms of LSMPAs along three themes: (1) placement, governance, and management; (2) political expediency; and (3) social-ecological value and cost. Through critical evaluation of scientific evidence, we discuss the value, achievements, challenges, and potential of LSMPAs in these arenas. We conclude that although some criticisms are valid and need addressing, none pertain exclusively to LSMPAs, and many involve challenges ubiquitous in management. We argue that LSMPAs are an important component of a diversified management portfolio that tempers potential losses, hedges against uncertainty, and enhances the probability of achieving sustainably managed oceans.

TIcaGrEloR and Absorb bioresorbable vascular scaffold implantation for recovery of vascular function after successful chronic total occlusion recanalization (TIGER-BVS trial): Rationale and study design.

OBJECTIVES: To explore the role of ticagrelor versus clopidogrel in coronary blood flow normalization immediately after chronic coronary total occlusion (CTO) recanalization. BACKGROUND: Coronary vascular function of a CTO immediately after recanalization is demonstrated to be poor. METHODS: The TIGER BVS is a prospective, double-randomized, open-label, two parallel-group controlled clinical trial to evaluate efficacy of ticagrelor versus clopidogrel in improving vascular function of coronary segment distal to CTO immediately after CTO recanalization. A total of 50 patients who receive CTO PCI will be randomized 1:1 to receive ticagrelor versus clopidogrel at least 3 days before the procedure. Immediately after CTO recanalization with Absorb BVS implantation, a specific study of vascular function under adenosine infusion will be performed. Patients will be therefore randomized 1:1 to receive angiographic follow-up with vascular function and optical coherence tomography analyses at 1- or 3-year follow-up. This study is registered on ClinicalTrials.gov with number NCT02211066. CONCLUSIONS: The TIGER BVS trial will provide the first randomized comparison between ticagrelor versus clopidogrel in recovering vascular function in CTO patients. It will also provide important data on vascular restoration therapy of Absorb BVS in this scenario.

Familial cortical dysplasia caused by mutation in the mammalian target of rapamycin regulator NPRL3.

We describe first cousin sibling pairs with focal epilepsy, one of each pair having focal cortical dysplasia (FCD) IIa. Linkage analysis and whole-exome sequencing identified a heterozygous germline frameshift mutation in the gene encoding nitrogen permease regulator-like 3 (NPRL3). NPRL3 is a component of GAP Activity Towards Rags 1, a negative regulator of the mammalian target of rapamycin complex 1 signaling pathway. Immunostaining of resected brain tissue demonstrated mammalian target of rapamycin activation. Screening of 52 unrelated individuals with FCD identified 2 additional patients with FCDIIa and germline NPRL3 mutations. Similar to DEPDC5, NPRL3 mutations may be considered as causal variants in patients with FCD or magnetic resonance imaging-negative focal epilepsy.

Caffeine-mediated BDNF release regulates long-term synaptic plasticity through activation of IRS2 signaling.

Caffeine has cognitive-enhancing properties with effects on learning and memory, concentration, arousal and mood. These effects imply changes at circuital and synaptic level, but the mechanism by which caffeine modifies synaptic plasticity remains elusive. Here we report that caffeine, at concentrations representing moderate to high levels of consumption in humans, induces an NMDA receptor-independent form of LTP (CAF LTP) in the CA1 region of the hippocampus by promoting calcium-dependent secretion of BDNF, which subsequently activates TrkB-mediated signaling required for the expression of CAF LTP. Our data include the novel observation that insulin receptor substrate 2 (IRS2) is phosphorylated during induction of CAF LTP, a process that requires cytosolic free Ca2+ . Consistent with the involvement of IRS2 signals in caffeine-mediated synaptic plasticity, phosphorylation of Akt (Ser473) in response to LTP induction is defective in Irs2-/- mice, demonstrating that these plasticity changes are associated with downstream targets of the phosphoinositide 3-kinase (PI3K) pathway. These findings indicate that TrkB-IRS2 signals are essential for activation of PI3K during the induction of LTP by caffeine.