Checkpoint-blocker-induced autoimmunity is associated with favourable outcome in metastatic melanoma and distinct T-cell expression profiles

Background Immune checkpoint blockers (ICBs) activate CD8⁺ T cells, eliciting both anti-cancer activity and immune-related adverse events (irAEs). The relationship of irAEs with baseline parameters and clinical outcome is unclear.Methods Retrospective evaluation of irAEs on survival was performed across primary (N = 144) and secondary (N = 211) independent cohorts of patients with metastatic melanoma receiving single agent (pembrolizumab/nivolumab—sICB) or combination (nivolumab and ipilimumab—cICB) checkpoint blockade. RNA from pre-treatment and post-treatment CD8⁺ T cells was sequenced and differential gene expression according to irAE development assessed.Results 58.3% of patients developed early irAEs and this was associated with longer progression-free (PFS) and overall survival (OS) across both cohorts (log-rank test, OS: P < 0.0001). Median survival for patients without irAEs was 16.6 months (95% CI: 10.9–33.4) versus not-reached (P = 2.8 × 10⁻⁶). Pre-treatment monocyte and neutrophil counts, but not BMI, were additional predictors of clinical outcome. Differential expression of numerous gene pathway members was observed in CD8⁺ T cells according to irAE development, and patients not developing irAEs demonstrating upregulated CXCR1 pre- and post-treatment.Conclusions Early irAE development post-ICB is associated with favourable survival in MM. Development of irAEs is coupled to expression of numerous gene pathways, suggesting irAE development in-part reflects baseline immune activation.Subject terms: Immunotherapy, Melanoma     

缺血性卒中或短暂性脑缺血发作患者的卒中预防指南

这份新声明旨在为缺血性卒中或短暂性脑缺血发作存活者的缺血性卒中预防提供全面和及时的循证推荐，循证推荐包括对危险因素的控制，动脉粥样硬化性疾病的干预措施，心源性栓塞的抗栓治疗以及非心源性卒中抗血小板药的应用。另外，还为其他多种特殊情况下复发性卒中的预防提供了推荐、包括动脉夹层分离、卵圆孔未闭、高同型半胱氨酸血症、高凝状态、镰状细胞病、脑静脉窦血栓形成、女性卒中（特别是与妊娠和绝经后激素替代治疗相关卒中），脑出血后肮凝药的应用，以及该指南在高危人群中执行和应用的特殊措施。     

Comorbidities of migraine: a user-friendly overview

Comorbidity of migraine is important from a number of different perspectives. Co-occurrence of different diseases may complicate diagnosis as a high degree of symptomatic overlap may occur among conditions associated with migraine. Furthermore, comorbidity has also important implications for treatment. The commonest comorbidities of migraine are represented by psychiatric disorders, epilepsy, tremor, stroke, and cardiovascular abnormalities.     

Synthesis and characterization of dextran carboxylates for the specific chemical modification of human hemoglobin

The present study deals with the fixing of benzenehexacarboxylate (BHC) on dextran, with the aim of obtaining polyanionic polymers capable of decreasing the oxygen affinity of hemoglobin (Hb) by interacting with its phosphate binding site (allosteric site). The covalent coupling of these polymers onto oxyHb has been investigated for the synthesis of oxygen carriers with low oxygen affinity. This type of covalent conjugate could be of interest in intravascular use. Several steps were necessary to synthesize dextran with linked BHC (DEX-BHC). In each step, the structure of the modified dextran was determined by means of gel permeation chromatography, ¹H and ¹³C NMR spectroscopy, and low-angle laser light scattering. The aim was to determine the conditions of the reaction which lead to a minimization of cross-linking phenomena. The DEX-BHC obtained (0,27 mmol BHC/g polymer) decreased the oxygen affinity of Hb in the same way as the natural effector, 2,3-diphosphoglycerate (2,3-DPG) i.e., by reacting specifically with the amines of the protein allosteric site. This decrease in oxygen affinity was more accentuated after covalent coupling onto oxyHb, which means that the fixing point was probably localized in the 2,3-DPG binding site.     

The role of nitrinergic connections in central cardiovascular responses mediated by physostigmine infused into posterior hypothalamus

In the last few decades, cholinergic connections located into posterior hypothalamus (PH) have been implicated in the central regulation of blood pressure (BP). Here we investigated the role of nitric oxide (NO) in the blood pressure response elicited by infusion of physostigmine into PH of normotensive rats. In freely moving rats, physostigmine (60-200 nM) produced a dose- and time-dependent elevation of BP which was antagonized by the antimuscarinic drug scopolamine (60 nM) and by L-NAME (100 microM), an inhibitor of NO synthase, both infused into the same site. In contrast, L-arginine (L-Arg; 100 microM), the precursor of NO, and glyceryltrinitrate (GTN; 140 nM), an NO donor, infused into the PH did not affect physostigmine-related pressor response. In rats pre-treated with Escherichia coli lipopolisaccharide (LPS; 0.5 microg i.p. 24h beforehand), however, scopolamine, L-Arg and GTN produced a decrease of BP, an effect antagonized by L-NAME. This suggests that NO only slightly modulates physostigmine-related pressor response elicited into PH of LPS-untreated rats. In contrast, the release of large amounts of NO generated by pre-treating rats with LPS, down-regulates cholinergic connections located at the PH, thus contributing in the central dysregulation of BP which can be found when high circulating endotoxin levels may occur.     

A-Type potassium currents active at subthreshold potentials in mouse cerebellar purkinje cells

Voltage-dependent and calcium-independent K⁺ currents were whole-cell recorded from cerebellar Purkinje cells in slices. Tetraethylammonium (TEA, 4 m m ) application isolated an A-type K⁺ current ( I _{k ( a )}) with a peak amplitude, at +20 mV, of about one third of the total voltage-dependent and calcium-independent K⁺ current. The I _{k ( a )} activated at about −60 mV, had a V _0.5 of activation of −24.9 mV and a V _0.5 of inactivation of −69.2 mV. The deactivation time constant at −70 mV was 3.4 ± 0.4 ms, while the activation time constant at +20 mV was 0.9 ± 0.2 ms. The inactivation kinetics was weakly voltage dependent, with two time constants; those at +20 mV were 19.3 ± 3.1 and 97.6 ± 9.8 ms. The recovery from inactivation had two time constants of 60.8 ms (78.4%) and 962.3 ms (21.6%). The I _{k ( a )} was blocked by 4-aminopyridine with an IC₅₀ of 67.6 μM. Agitoxin-2 (2 n m ) blocked 17.4 ± 2.1% of the I _{k ( a )}. Flecainide completely blocked the I _{k ( a )} with a biphasic effect with IC₅₀ values of 4.4 and 183.2 μM. In current-clamp recordings the duration of evoked action potentials was affected neither by agitoxin-2 (2 n m ) nor by flecainide (3 μM), but action potentials that were already broadened by TEA were further prolonged by 4-aminopyridine (100 μM). The amplitude of the hyperpolarisation at the end of depolarising steps was reduced by all these blockers.     

Antigen-specific B-cell unresponsiveness induced by chronic Mycobacterium avium subsp. paratuberculosis infection of cattle

Mycobacterium avium subsp. paratuberculosis infection of cattle results in a chronic granulomatous enteritis. Clinical disease (i.e., cachexia, diarrhea, and high fecal bacterial counts) is preceded by a lengthy subclinical stage of disease. The immunologic mechanisms associated with the progression of infected cattle from subclinical to clinical disease are unclear. In this study, a cell proliferation assay was used in combination with flow cytometry to compare peripheral blood lymphocyte responses of cattle with subclinical paratuberculosis to responses of cattle with clinical paratuberculosis. B cells from cattle with subclinical disease proliferated vigorously upon stimulation with M. avium subsp. paratuberculosis antigen, with up to 12.4% of the total B cells responding. However, B cells from cattle with clinical disease did not proliferate upon antigen stimulation despite good proliferation in response to concanavalin A stimulation. In addition, these animals had high percentages of peripheral blood B cells. B cells from noninfected animals did not proliferate upon M. avium subsp. paratuberculosis antigen stimulation. Thus, it appears that B-cell proliferation is a sensitive indicator of subclinical Johne's disease. Furthermore, the immunologic mechanisms responsible for the antigen-specific unresponsiveness of peripheral blood B cells may be significant in the eventual progression from subclinical to clinical Johne's disease in cattle.