13 research outputs found
p75NTR antagonists attenuate photoreceptor cell loss in murine models of retinitis pigmentosa
ProNGF signaling through p75NTR has been associated with neurodegenerative disorders. Retinitis pigmentosa (RP) comprises a group of inherited retinal dystrophies that causes progressive photoreceptor cell degeneration and death, at a rate dependent on the genetic mutation. There are more than 300 mutations causing RP, and this is a challenge to therapy. Our study was designed to explore a common mechanism for p75NTR in the progression of RP, and assess its potential value as a therapeutic target. The proNGF/p75NTR system is present in the dystrophic retina of the rd10 RP mouse model. Compared with wild-type (WT) retina, the levels of unprocessed proNGF were increased in the rd10 retina at early degenerative stages, before the peak of photoreceptor cell death. Conversely, processed NGF levels were similar in rd10 and WT retinas. ProNGF remained elevated throughout the period of photoreceptor cell loss, correlating with increased expression of α2-macroglobulin, an inhibitor of proNGF processing. The neuroprotective effect of blocking p75NTR was assessed in organotypic retinal cultures from rd10 and RhoP mouse models. Retinal explants treated with p75NTR antagonists showed significantly reduced photoreceptor cell death, as determined by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay and by preservation of the thickness of the outer nuclear layer (ONL), where photoreceptor nuclei are located. This effect was accompanied by decreased retinal-reactive gliosis and reduced TNFα secretion. Use of p75NTR antagonist THX-B (1,3-diisopropyl-1-[2-(1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydro-purin-7-yl)-acetyl]-urea) in vivo in the rd10 and RhoP mouse models, by a single intravitreal or subconjunctival injection, afforded neuroprotection to photoreceptor cells, with preservation of the ONL. This study demonstrates a role of the p75NTR/proNGF axis in the progression of RP, and validates these proteins as therapeutic targets in two different RP models, suggesting utility irrespective of etiology.Fil: Platón-Corchado, María. Consejo Superior de Investigaciones Científicas; EspañaFil: Barcelona, Pablo Federico. Mc Gill University. Lady Davis Research Intitute; Canadá. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Jmaeff, Sean. Mc Gill University. Lady Davis Research Intitute; CanadáFil: Marchena, Miguel. Consejo Superior de Investigaciones Científicas; EspañaFil: Hernández-Pinto, Alberto M.. Consejo Superior de Investigaciones Científicas; EspañaFil: Hernández-Sánchez, Catalina. Consejo Superior de Investigaciones Científicas; EspañaFil: Saragovi, H. Uri. Mc Gill University. Lady Davis Research Intitute; CanadáFil: de la Rosa, Enrique J. Centro de Investigaciones Biológicas; Españ
Intravitreal injection of proinsulin-loaded microspheres delays photoreceptor cell death and vision loss in the rd10 mouse model of retinitis pigmentosa
9 p.-6 fig.PURPOSE. The induction of proinsulin expression by transgenesis or intramuscular gene therapy has been shown previously to retard retinal degeneration in mouse and rat models of retinitis pigmentosa (RP), a group of inherited conditions that result in visual impairment. We investigated whether intraocular treatment with biodegradable poly (lactic-co-glycolic) acid microspheres (PLGA-MS) loaded with proinsulin has cellular and functional neuroprotective effects in the retinaMETHODS. Experiments were performed using the Pde6brd10 mouse model of RP.
Methionylated human recombinant proinsulin (hPI) was formulated in PLGA-MS, which
were administered by intravitreal injection on postnatal days (P) 14 to 15. Retinal
neuroprotection was assessed at P25 by electroretinography, and by evaluating outer nuclear layer (ONL) cellular preservation. The attenuation of photoreceptor cell death by hPI was determined by TUNEL assay in cultured P22 retinas, as well as Akt phosphorylation by immunoblottingRESULTS. We successfully formulated hPI PLGA-MS to deliver the active molecule for several weeks in vitro. The amplitude of b-cone and mixed b-waves in electroretinographic recording was significantly higher in eyes injected with hPI-PLGA-MS compared to control eyes.Treatment with hPI-PLGA-MS attenuated photoreceptor cell loss, as revealed by comparing ONL thickness and the number of cell rows in this layer in treated versus untreated retinas. Finally, hPI prevented photoreceptor cell death and increased AktThr308 phosphorylation in organotypic cultured retinas.CONCLUSIONS. Retinal degeneration in the rd10 mouse was slowed by a single intravitreal injection of hPI-PLGA-MS. Human recombinant proinsulin elicited a rapid and effective neuroprotective effect when administered in biodegradable microspheres, which may constitute a future potentially feasible delivery method for proinsulin-based treatment of RP.Supported by Grants from the Spanish Ministerio de Ciencia e
Innovacion (MICINN) and Spanish Ministerio de EconomÍa y
Competitividad (MINECO), SAF2010-21879 (EJdlR and PdlV),
SAF2013-41059-R (FdP and EJdlR), and technical personnel
support from CIBERDEM, ISCIII, Madrid, SpainPeer reviewe
Predicting serious complications in patients with cancer and pulmonary embolism using decision tree modelling: the EPIPHANY Index
Background: Our objective was to develop a prognostic stratification tool that enables patients with cancer and pulmonary embolism (PE), whether incidental or symptomatic, to be classified according to the risk of serious complications within 15 days. Methods: The sample comprised cases from a national registry of pulmonary thromboembolism in patients with cancer (1075 patients from 14 Spanish centres). Diagnosis was incidental in 53.5% of the events in this registry. The Exhaustive CHAID analysis was applied with 10-fold crossvalidation to predict development of serious complications following PE diagnosis. Results: About 208 patients (19.3%, 95% confidence interval (CI), 17.1-21.8%) developed a serious complication after PE diagnosis. The 15-day mortality rate was 10.1%, (95% CI, 8.4-12.1%). The decision tree detected six explanatory covariates: Hestia-like clinical decision rule (any risk criterion present vs none), Eastern Cooperative Group performance scale (ECOG-PS; = 2), O-2 saturation (= 90%), presence of PE-specific symptoms, tumour response (progression, unknown, or not evaluated vs others), and primary tumour resection. Three risk classes were created (low, intermediate, and high risk). The risk of serious complications within 15 days increases according to the group: 1.6, 9.4, 30.6%; P<0.0001. Fifteen-day mortality rates also rise progressively in low-, intermediate-, and high-risk patients: 0.3, 6.1, and 17.1%; P<0.0001. The cross-validated risk estimate is 0.191 (s.e. = 0.012). The optimism-corrected area under the receiver operating characteristic curve is 0.779 (95% CI, 0.717-0.840). Conclusions: We have developed and internally validated a prognostic index to predict serious complications with the potential to impact decision-making in patients with cancer and PE
Association Between Preexisting Versus Newly Identified Atrial Fibrillation and Outcomes of Patients With Acute Pulmonary Embolism
Background Atrial fibrillation (AF) may exist before or occur early in the course of pulmonary embolism (PE). We determined the PE outcomes based on the presence and timing of AF. Methods and Results Using the data from a multicenter PE registry, we identified 3 groups: (1) those with preexisting AF, (2) patients with new AF within 2 days from acute PE (incident AF), and (3) patients without AF. We assessed the 90-day and 1-year risk of mortality and stroke in patients with AF, compared with those without AF (reference group). Among 16 497 patients with PE, 792 had preexisting AF. These patients had increased odds of 90-day all-cause (odds ratio [OR], 2.81; 95% CI, 2.33-3.38) and PE-related mortality (OR, 2.38; 95% CI, 1.37-4.14) and increased 1-year hazard for ischemic stroke (hazard ratio, 5.48; 95% CI, 3.10-9.69) compared with those without AF. After multivariable adjustment, preexisting AF was associated with significantly increased odds of all-cause mortality (OR, 1.91; 95% CI, 1.57-2.32) but not PE-related mortality (OR, 1.50; 95% CI, 0.85-2.66). Among 16 497 patients with PE, 445 developed new incident AF within 2 days of acute PE. Incident AF was associated with increased odds of 90-day all-cause (OR, 2.28; 95% CI, 1.75-2.97) and PE-related (OR, 3.64; 95% CI, 2.01-6.59) mortality but not stroke. Findings were similar in multivariable analyses. Conclusions In patients with acute symptomatic PE, both preexisting AF and incident AF predict adverse clinical outcomes. The type of adverse outcomes may differ depending on the timing of AF onset.info:eu-repo/semantics/publishedVersio
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Fractured Wire in the Left Internal Mammary Artery: A Novel Retrieval Technique
Although fractured coronary wires are a rare occurrence, failure to retrieve them successfully puts patients at undue risk. We offer a technique that can be used when traditional retrieval with a Microsnare system is unsuccessful
Effect of clonidine on heart rate variability in congestive heart failure
In patients with congestive heart failure, abnormal heart rate variability is a predictor of total mortality and sudden cardiac death. Drugs that improve heart rate variability may have a potential role for improving the survival among these patients. The effects of clonidine were studied in 24 patients with congestive heart failure, sinus rhythm, a left ventricular ejection fraction 115 mm Hg. A 6-minute corridor walk test and 24-hour Holter monitoring were performed before and 42 ± 24 days after initiation of clonidine therapy (Catapres-TTS patch, mean dose: 0.33 ± 0.21 mg). Changes in other medications used at baseline were not allowed. One patient died suddenly. Two patients did not complete the protocol due to worsening congestive heart failure, which required changes in medications, 1 patient discontinued due to hypotension, and 2 for personal reasons. Among the 18 patients who completed the protocol, the mean RR interval of sinus beats increased from 760 ± 106 to 822 ± 125 ms (p = 0.001) and the distance covered during the 6-minute walk test increased from 1,148 ± 277 to 1,255 ± 359 feet (p = 0.042). Systolic blood pressure decreased from 139 ± 15 to 119 ± 10 mm Hg (p <0.0001). The following increases were noted in the heart rate variability measurements: high-frequency power in 0.15 to 0.40 Hz: 4.58 ± 1.07 to 4.94 ± 1.17 ln (ms), p = 0.002; SD: 47.0 ± 16.9 to 52.5± 18.4 ms, p = 0.034; SD of the mean of all RR intervals in 24 hours: 116 ± 94 to 130 ± 19 ms, p = 0.033; SD of all 5-minute mean RR intervals: 106 ± 44 to124 ± 66 ms, p = 0.042; root-mean square of difference of successive RR intervals: 28.8 ± 10.7 to 34.1 ± 14.2 ms, p = 0.017. Clonidine improves heart rate variability in the patients with congestive heart failure by increasing the parasympathetic tone. It is well tolerated by most patients with heart failure and may have a beneficial effect on exercise capacity
Different Types of Statins and All-Cause Mortality during Anticoagulation for Venous Thromboembolism: Validation Study from RIETE Registry.
Introduction We previously reported that during the course of anticoagulation for venous thromboembolism (VTE) patients using statins were at a lower risk to die than nonusers. Methods We used the R egistro I nformatizado E nfermedad T rombo E mbólica (RIETE) registry to validate our previous findings in a subsequent cohort of patients and to compare the risk of death according to the use of different types of statins. Results From January 2018 to December 2019, 19,557 patients with VTE were recruited in RIETE. Of them, 4,065 (21%) were using statins (simvastatin, 1,406; atorvastatin, 1,328; rosuvastatin, 246; and others, 1,085). During anticoagulation (192 vs.182 days, for statin and no statin users respectively), 500 patients developed a VTE recurrence, 519 suffered major bleeding, and 1,632 died (fatal pulmonary embolism [PE], 88 and fatal bleeding, 78). On multivariable analysis, statin users were at a lower risk to die (hazard ratio [HR] = 0.68; 95% confidence interval [CI]: 0.59-0.79) than nonusers. When separately analyzing the drugs, on multivariable analysis, patients using simvastatin (HR = 0.64; 95% CI: 0.52-0.80), atorvastatin (HR 0.72; 95% CI: 0.58-0.89), or other statins (HR = 0.67; 95% CI: 0.52-0.87) were at a lower risk to die than nonusers. For those using rosuvastatin, difference was not statistically significant (HR = 0.77; 95% CI: 0.50-1.19), maybe due to the sample size. Conclusion Our data validate previous findings and confirm that VTE patients using statins at baseline are at a lower risk to die than nonusers. No statistically differences were found according to type of statins.status: Published onlin
Variation in chemokines plasma concentrations in primary care depressed patients associated with Internet-based cognitive-behavioral therapy
How the presence of inflammation has repercussions for brain function is a topic of active research into depression. Signals released from immune system-related cells, including chemokines, might be indicative of active depression and can, hypothetically, serve as biomarkers of response to interventions, both pharmacological and psychological. The objective of this study is to analyze the peripheral plasma concentrations of CXCL12, CCL11, CX3CL1 and CCL2 in a cohort of depressed primary-care patients, as well as their evolution after an internet-based cognitive-behavioral intervention. The concentrations of those chemokines were measured in 66 primary-care patients with mild and moderate depression, before and after the intervention, as well as 60 controls, using multiplex immunoassays. Concentrations of CXCL12 and CCL2 were significantly higher in the clinical sample in comparison with controls. A stable multivariate discriminative model between both groups was found. Concentrations of all chemokines decreased after the internet-based psychological intervention. These findings support the implication of chemokines in depression, even in a sample of patients with mild and moderate severity. Furthermore, they demonstrate the need for further multidisciplinary research that confirms how biomarkers such as plasma chemokines can serve as a marker for depression and are sensitive to non-pharmacological interventions
Impact of sex, age, and risk factors for venous thromboembolism on the initial presentation of first isolated symptomatic acute deep vein thrombosis
BACKGROUND AND AIMS: Sex-specific differences exist for the initial presentation of acute venous thromboembolism (VTE): men are more likely to present with proximal deep vein thrombosis (DVT) in the lower limbs (versus pulmonary embolism [PE] or isolated distal DVT [IDDVT]) than women. We studied in detail the influence of sex, age, and VTE risk factors on the initial presentation of IDDVT versus proximal DVT. METHODS: A total of 24,911 patients with a first episode of objectively diagnosed acute symptomatic lower-limb DVT (without symptomatic PE) were enrolled in RIETE (years 2000-2017) and included in the present analysis. RESULTS: A total of 4266 (17.1%) patients had IDDVT. No trend for more IDDVT diagnoses was observed over time. Women aged 40-69 had a higher proportion of IDDVT, especially between 40 and 49 years (+6.7%; 95CI +3.7%; +9.9%), whereas men had more often proximal DVT. The presenting location of first acute DVT depended on sex, age, and the prevalence and type of VTE risk factors. Recent surgery was independently associated with a diagnosis of IDDVT in both women and men, whereas active cancer and pregnancy were associated with proximal DVT. CONCLUSIONS: The interaction between age and VTE risk factors influences the presenting location (distal versus proximal) of the first acute lower-limb DVT observed in women and men. Our observations extend to IDDVT the concept that different clinical manifestations of acute VTE may not fully share the same pathophysiological mechanisms: this contributes to explain sex-specific prognostic differences.status: publishe