Methoprene treatment and its effect on male reproductive organ size and female remating in a fruit fly

Methoprene, a juvenile hormone analog, is used to accelerate sexual maturation in males of species of economic importance in support to the sterile insect technique (SIT). In the SIT, mass-reared sterile males are released into the field and need to survive until they reach sexual maturation, find a wild female, mate with her and then induce female sexual refractoriness, so she will not remate with a wild counterpart. The use of methoprene shortens the time between release and copulation. However, in South American fruit flies, Anastrepha fraterculus, the ability of methoprene-treated males to inhibit female remating has been shown to be lower than wild males, when methoprene was applied by pupal immersion or topical application. Here we evaluated the possibility of incorporating methoprene into the male diet at different doses and the ability of those males to inhibit female remating, as well as the effect of methoprene on male reproductive organ size, due to the possible correlation between male accessory gland size and their content, and the role of male accessory gland proteins in female inhibition. We found that A. fraterculus males fed with methoprene in the adult protein diet at doses as high as 1% were less likely to inhibit female remating, however, at all other lower doses males had the same ability as untreated males to inhibit female remating. Males fed with methoprene had bigger male accessory glands and testes compared to methoprene-deprived males. We demonstrate that the incorporation of methoprene in adult male diets is possible in this species and potentially useful as a post-teneral, pre-release supplement at doses as low as 0.01%. Even at higher doses, the percentage of females remating after 48 h from the first copulation is sufficiently low in this species so as not compromise the efficiency of the SIT.

Thirst distress in outpatients with heart failure in a Mediterranean zone of Spain

Aims

This study aimed to evaluate psychometric properties of the Spanish version of the Thirst Distress Scale for patients with Heart Failure (TDS‐HF) and to describe thirst distress‐associated factors in outpatients at a heart failure (HF) clinic in Spain. Thirst is common in patients with HF, but thirst distress has rarely been addressed and may significantly decrease quality of life.

Methods and results

A cross‐sectional study was performed assessing perceived thirst distress by patients with HF during the preceding 3 days, with the TDS‐HF (scores 8 to 40). Univariable and multivariable linear regression analyses were performed to identify variables independently associated with thirst distress. Three‐hundred two HF outpatients were included (age 67 ± 12 years, 74% male, HF duration 82 ± 75 months, left ventricular ejection fraction 42 ± 14%). Most patients were on treatment with fluid restriction (99%), sodium restriction (99%), and diuretics (70%). The psychometric evaluation of the Spanish version of the TDS‐HF showed satisfactory item‐total and inter‐item correlations (range from 0.77 to 0.85 and 0.60 to 0.84, respectively), and internal consistency was 0.95 (Cronbach's alpha). The majority perceived mild to moderate thirst distress, and 18% perceived it as high or severe. The mean score obtained was 16.2 ± 9.3 (median 13, Q1–Q3 8–20). Higher serum urea {beta coefficient 1.6 [95% confidence interval (CI) 0.267 to 2.92], P = 0.019} and lower potassium [beta coefficient −3.63 (85% CI −6.32 to −0.93), P = 0.009] remained significantly associated with thirst distress in the multivariable analysis, together with the dose of diuretics [beta coefficient 2.98 (95% CI 1.37 to 4.59), P < 0.001]. Treatment with angiotensin receptor blocker showed an independent protective effect [beta coefficient −3.62 (95% CI −6.89 to −0.345), P = 0.03].

Conclusions

The psychometric evaluation of the Spanish version of the TDS‐HF showed good psychometric properties. One in five patients experienced severe distress by thirst, but the majority had mild to moderate thirst distress. The dose of diuretics and angiotensin receptor blocker treatment influence thirst distress and could be clinically important targets to relieve thirst distress in patients with HF.

Irradiation dose does not affect male reproductive organ size, sperm storage, and female remating propensity in Ceratitis capitata

The Mediterranean fruit fly Ceratitis capitata is a globally invasive pest, often controlled with the sterile insect technique (SIT). For the SIT, mass-rearing of the target insect followed by irradiation are imperatives. Sterile males are often less able to inhibit female remating and transfer less number of sperm, and even irradiation could affect male reproductive organs, with consequences for their ability to inhibit female remating. On the other hand, male age could affect their ability to modulate female response after mating. Here, we evaluated the quality of the genetic sexing strain Vienna-8-tsl mass-reared in Bioplanta San Juan, Argentina, under laboratory conditions, with regard to: (i) the ability of sterile males irradiated at 100 or 140 Gy to inhibit female remating, in the same day and at 24 h of first copulation; (ii) the ability of 3, 4 or 5 day-old sterile males to inhibit female remating at 24 h of first copulation, and (iii) the effect of a reduction in irradiation doses on the number of sperm stored by females and reproductive organ size in virgin males. Sterile males were better able than wild males to inhibit female remating in the same day of first copulation and as able as wild males 1 day after first copulation. Male age did not affect their ability to inhibit female receptivity. Number of sperm stored by females, testes size and ectodermal accessory glands size were not affected by male identity, while sterile 100 Gy males had larger mesodermal accessory glands than control lab males. A reduction in irradiation dose does not impact any variable measured, except for percentage of sperm-depleted females: females mated with sterile 100 Gy males had lower probabilities to store sperm. The results showed here are very encouraging for tsl Vienna 8 strain reared in Argentina and are discussed in comparison with previous studies in C. capitata female remating with dissimilar results.

Cryptococcus bacillisporus (VGIII) Meningoencephalitis Acquired in Santa Cruz, Bolivia

We describe a case of chronic meningoencephalitis with hydrocephalus caused by Cryptococcus bacillisporus (VGIII) in an immunocompetent patient from Santa Cruz, Bolivia. This first report of a member of the Cryptococcus gattii species complex from Bolivia suggests that C. bacillisporus (VGIII) is present in this tropical region of the country and complements our epidemiological and clinical knowledge of this group of emerging fungal pathogens in South America.

Reconsidering systematic factors during the Covid-19 pandemic - The rising importance of ESG

We investigate the importance of Environmental, Social and Governance (ESG) ratings in explaining different industry returns during the Covid-19 window. We build our ESG factor as the spread in returns between firms in the top ESG quartile and those in the bottom ESG quartile. The ESG factor shows to significantly explain industry returns in addition to the Fama-French factors. We also analyze the individual Environmental, Social, and Governance components of ESG. Environmental and Social dimensions are the main drivers of the ESG impact on different industries.

Prognostic value of lung ultrasound in chronic stable ambulatory heart failure patients

INTRODUCTION AND OBJECTIVES

The role of lung ultrasound (LUS) in acute heart failure (HF) has been widely studied, but little is known about its usefulness in chronic HF. This study assessed the prognostic value of LUS in a cohort of chronic HF stable ambulatory patients.

METHODS

We included consecutive outpatients who attended a scheduled follow-up visit in a HF clinic. LUS was performed in situ. The operators were blinded to clinical data and examined 8 thoracic areas. The sum of B-lines across all lung zones and the quartiles of this addition were used for the analyses. Linear regression and Cox regression analyses were performed. The main clinical outcomes were a composite of all-cause death or hospitalization for HF and mortality from any cause.

RESULTS

A total of 577 individuals were included (72% men; 69± 12 years). The mean number of B-lines was 5±6. During a mean follow-up of 31±7 months, 157 patients experienced the main clinical outcome and 111 died. Having ≥ 8 B-lines (Q4) doubled the risk of experiencing the composite primary event (P <.001) and increased the risk of death from any cause by 2.6-fold (P <.001). On multivariate analysis, the total sum of B-lines remained independent predictive factor of the composite endpoint (HR, 1.04; 95%CI, 1.02-1.06; P=.002) and of all-cause death (HR, 1.04; 95%CI, 1.02-1.07; P=.001), independently of whether or not N-terminal pro-B-type natriuretic peptide (NT-proBNP) was included in the model (P=.01 and P=.008, respectively), with a 3% to 4% increased risk for each 1-line addition.

CONCLUSIONS

LUS identified patients with stable chronic HF at high risk of death or HF hospitalization.

Transcranial Doppler as a Predictor of Ischemic Events in Vertebral Artery Dissection

BACKGROUND AND PURPOSE

Transcranial Doppler (TCD) helps identify patients with carotid dissections at risk of ischemic events (IEs). There is paucity of data identifying independent predictors of IE in vertebral arterial dissection (VAD). We sought to investigate the clinical and ultrasound predictors of IE.

METHODS

Patients with VAD admitted between June 2017 and February 2020 were evaluated clinically and with TCD; sonographic curves, microembolic signals (MES), and the breath-holding index (BHI) test were applied. Covariates found on univariate screen (P < .25) were included in a multivariable linear regression to identify independent predictors of IEs.

RESULTS

Of 88 patients with 100 VAD, 75 (85.2%) were females with a mean age 37.9 ± 7.5 years. All patients received antiplatelet treatment. TCD monitoring lasted an average of 21 ± 2.1 minutes. TCD was abnormal in 23 cases (26.1%); 21 patients had abnormal sonographic curves in the vertebral/basilar arteries, while in 4 cases, MES were present and in 5 (4.5%), BHI was abnormal. None of the patients with a normal TCD had an IE. Six strokes occurred during follow up. On univariate analysis, male sex, diabetes, dyslipidemia, a previous myocardial infarct, migraine, time of consultation to the ER, bilateral VAD, MES, BHI abnormalities, post stenotic flow in the basilar artery (PFB), and basilar/vertebral velocities were significantly associated with the risk of IEs. In the multivariate analysis, only the presence of PFB was a significant predictor of IE (OR: 68.6, 95% CI 5-937, <.001).

CONCLUSIONS

TCD in VAD predicts patients at high risk of IE.

Cervical Artery Dissections with and without stroke, risk factors and prognosis: a Chilean prospective cohort

We aimed to characterize spontaneous cervical artery dissection (CeAD) patients with and without stroke and describe risk factors for cerebrovascular complications in a Chilean prospective cohort.

METHODS

Consecutive CeAD patients admitted to a Chilean center confirmed by neuroimaging. Logistic regression was used.

RESULTS

168 patients were included, median follow-up time was 157 days. Stroke occurred in 49 (29.2%) cases, 4 (2%) patients died, all of whom had a stroke, and 10 (6%) presented CeAD recurrence. In univariate analyses, men (odds ratio [OR] 3.97, 95% confidence interval [CI] 1.97-8.00, P < 0.001), internal carotid artery CeAD (OR 2.82, 95% CI 1.38-5.78, P = 0.005) and vessel occlusion (OR 4.45, 95% CI 1.38-14.38, P = 0.035) increased stroke risk. Conversely, vertebral artery dissection (OR 0.35, 95% CI 0.16-0.74, P = 0.006) and longer symptom onset to admission (O-A) time (OR 0.79, 95% CI 0.70-0.90, P < 0.001) were associated to decreased stroke risk. After multivariate analysis, men (OR 2.88, 95% CI 1.32-6.27, P = 0.008) and O-A time (OR 0.80, 95% CI 0.69-0.92, P = 0.002) remained independently associated with stroke.

CONCLUSION

CeAD presented commonly as a non-stroke entity, with favorable prognosis. Albeit to a higher frequency of CeAD in women, stroke occurred predominantly in men, who were admitted earlier.

Fecal pollution source tracking and thalassogenic diseases: The temporal-spatial concordance between maximum concentrations of human mitochondrial DNA in seawater and Hepatitis A outbreaks among a coastal population

Fecal pollution source tracking (FST) studies the origin of fecal contamination and promotes action to eliminate it to improve human health and environmental sustainability. This work presents the temporal and spatial relations of human mitochondrial DNA (HmtDNA), fecal coliforms (FC) and live microbial biomass (ATP) in seawater during a hepatitis A outbreak among a human coastal population. The study area is approximately 100 km along the coastline of the Biobío Region in the southeastern Pacific (Humboldt Current System, Chile). Total data from the swash zone from summer 2015 to autumn 2016 show there were significant positive log-log correlations between FC and HmtDNA (R = 0.32) and ATP (R = 0.31). These correlations were highest during the austral spring of 2015 (R = 0.53 and 0.58 respectively), when HmtDNA also correlated significantly with ATP (R = 0.86). Maximum average values of the parameters measured in this season showed a temporal-spatial concordance with the peak in the number of hepatitis A cases among the nearby coastal population. FC correlated significantly with HmtDNA (R = 0.98) in the water column of the coastal zone close to Concepción Bay during the austral summer of 2016 and in the swash zone of the bay (R = 0.68) throughout the study period. Hepatitis A virus (HAV) has also been detected in organisms and seawater in Concepción Bay, which is consistent with the high incidence of hepatitis A among the coastal population. The concordance between human fecal pollution in the study area and a seasonal hepatitis A outbreak strongly suggests that HmtDNA and its relation with FC and ATP in the coastal zone of marine environments can be used as a proxy to evaluate the risk of outbreaks of thalassogenic diseases.

Effects of pharyngeal suction on the arterial oxygen saturation and heart rate in healthy newborns delivered by elective cesarean section

OBJECTIVE

To evaluate the effect of oro-and naso- pharyngeal suction (ONPS) on the SpO2 and heart rate (HR) in healthy term newborns delivered by cesarean section, at the first minutes after birth.

PATIENTS AND METHODS

We conducted a prospective randomized trial. Newborns were randomized to ONPS and No-ONSP groups. Continuous readings of SpO2 and HR were performed during the first 10 minutes, and subsequently at 15, 30 and 60 minutes after birth.

RESULTS

A total of 84 newborns were evaluated; 42 in ONPS group and 42 in No-ONPS group, with mean gestational age and birth weight±SD of 38.4 weeks and 3533±403 g in the ONPS group and 38.0 weeks and 3575±568 g in the No-ONPS group. The mean SpO2±SD at the first minute of life in the former group was 52.6±7.6% vs 56.1±10.8% on the latter; with no significant difference (p = 0.28). The mean HR±SD at first minute of life was 137±25 in the No-ONPS and 148±13 in the ONPS group (p = 0.02), but no difference was found in the subsequent minutes.

CONCLUSION

Not performing ONPS in newborns delivered by cesarean section does not affect SpO2 and HR in the first postpartum hour.

A combination of hydroxytyrosol, omega-3 fatty acids and curcumin improves pain and inflammation among early stage breast cancer patients receiving adjuvant hormonal therapy: results of a pilot study

PURPOSE

Breast cancer patients receiving hormonal therapies face risks of relapse, increased rates of cardiovascular events, and toxicities of therapy such as aromatase inhibitor (AI)-associated musculoskeletal symptoms (AIMSS). C-reactive protein (CRP), a marker for inflammation, is associated with breast cancer outcomes. We evaluated whether the olive-derived polyphenol hydroxytyrosol combined with omega-3 fatty acids and curcumin would reduce CRP and musculoskeletal symptoms in breast cancer patients receiving adjuvant hormonal therapies.

EXPERIMENTAL DESIGN

This prospective, multicenter, open-label, single arm, clinical trial enrolled post-menopausal breast cancer patients (n = 45) with elevated C-reactive protein (CRP) taking predominantly aromatase inhibitors to receive a combination of hydroxytyrosol, omega-3 fatty acids, and curcumin for 1 month. CRP, other inflammation-associated cytokines, and pain scores on the Brief Pain Inventory were measured before therapy, at the end of therapy and 1 month after completion of therapy.

RESULTS

CRP levels declined during the therapy [from 8.2 ± 6.4 mg/L at baseline to 5.3 ± 3.2 mg/L (p = 0.014) at 30 days of treatment], and remained decreased during the additional 1 month off therapy. Subjects with the highest baseline CRP levels had the greatest decrease with the therapy. Pain scores also decreased during the therapy. There were no significant adverse events.

CONCLUSIONS

The combination of hydroxytyrosol, omega-3 fatty acids, and curcumin reduced inflammation as indicated by a reduction in CRP and reduced pain in patients with aromatase-induced musculoskeletal symptoms. Longer studies comparing this combination to other anti-inflammatories in larger groups of patients with clinical outcome endpoints are warranted.

Comorbidities, Fragility, and Quality of Life in Heart Failure Patients With Midrange Ejection Fraction

Objective

To assess the effects of comorbidities, fragility, and quality of life (QOL) on long-term prognosis in ambulatory patients with heart failure (HF) with midrange left ventricular ejection fraction (HFmrEF), an unexplored area.

Patients and Methods

Consecutive patients prospectively evaluated at an HF clinic between August 1, 2001, and December 31, 2015, were retrospectively analyzed on the basis of left ventricular ejection fraction category. We compared patients with HFmrEF (n=185) to those with reduced (HFrEF; n=1058) and preserved (HFpEF; n=162) ejection fraction. Fragility was defined as 1 or more abnormal evaluations on 4 standardized geriatric scales (Barthel Index, Older Americans Resources and Services scale, Pfeiffer Test, and abbreviated-Geriatric Depression Scale). The QOL was assessed with the Minnesota Living with Heart Failure Questionnaire. A comorbidity score (0-7) was constructed. All-cause death, HF-related hospitalization, and the composite end point of both were assessed.

Results

Comorbidities and QOL scores were similar in HFmrEF (2.41±1.5 and 30.1±18.3, respectively) and HFrEF (2.30±1.4 and 30.8±18.5, respectively) and were higher in HFpEF (3.02±1.5, P<.001, and 36.5±20.7, P=.003, respectively). No statistically significant differences in fragility between HFmrEF (48.6%) and HFrEF (41.9%) (P=.09) nor HFpEF (54.3%) (P=.29) were found. In univariate analysis, the association of comorbidities, QOL, and fragility with the 3 end points was higher for HFmrEF than for HFrEF and HFpEF. In multivariate analysis, comorbidities were independently associated with the 3 end points (P≤.001), and fragility was independently associated with all-cause death and the composite end point (P<.001) in HFmrEF.

Conclusion

Comorbidities and fragility are independent predictors of outcomes in ambulatory patients with HFmrHF and should be considered in the routine clinical assessment of HFmrEF.

AFLP diversity and spatial structure of Calycophyllum candidissimum (Rubiaceae), a dominant tree species of Nicaragua's critically endangered seasonally dry forest

The Central American seasonally dry tropical (SDT) forest biome is one of the worlds' most endangered ecosystems, yet little is known about the genetic consequences of its recent fragmentation. A prominent constituent of this biome is Calycophyllum candidissimum, an insect-pollinated and wind-dispersed canopy tree of high socio-economic importance, particularly in Nicaragua. Here, we surveyed amplified fragment length polymorphisms across 13 populations of this species in Nicaragua to elucidate the relative roles of contemporary vs historical factors in shaping its genetic variation. Genetic diversity was low in all investigated populations (mean HE=0.125), and negatively correlated with latitude. Overall population differentiation was moderate (ΦST=0.109, P<0.001), and Bayesian analysis of population structure revealed two major latitudinal clusters (I: 'Pacific North'+'Central Highland'; II: 'Pacific South'), along with a genetic cline between I and II. Population-based cluster analyses indicated a strong pattern of 'isolation by distance' as confirmed by Mantel's test. Our results suggest that (1) the low genetic diversity of these populations reflects biogeographic/population history (colonisation from South America, Pleistocene range contractions) rather than recent human impact; whereas (2) the underlying process of their isolation by distance pattern, which is best explained by 'isolation by dispersal limitation', implies contemporary gene flow between neighbouring populations as likely facilitated by the species' efficient seed dispersal capacity. Overall, these results underscore that even tree species from highly decimated forest regions may be genetically resilient to habitat fragmentation due to species-typical dispersal characteristics, the necessity of broad-scale measures for their conservation notwithstanding.

[Thrombolysis in stroke mimics: Experience in 10 cases]

BACKGROUND

The effectiveness of intravenous thrombolysis (IVT) in cerebral ischemia is time dependent. Stroke mimics (SM) are frequent in emergency rooms. The effort to reduce door to needle time, can lead to administer thrombolytics to SM.

AIM

To describe the frequency and prognosis of SM treated with IVT.

MATERIAL AND METHODS

Prospective analysis of all patients evaluated in a Chilean private clinic between December 2004 and July 2015 with a suspected acute ischemic stroke (AIS). We calculated the number of SM that were treated with IVT. In these patients, we analyzed the presence of symptomatic cerebral hemorrhage defined as the presence of a neurological deterioration of four points or more on the National Institute of Health Stroke Scale, the presence of extracranial bleeding according to Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries criteria and the patient's functional status at three months by modified Rankin scale (MRS).

RESULTS

We evaluated 1,417 patients with suspected AIS, of which 240 (16.9%) were finally diagnosed as SM. A total of 197 patients were treated with IVT, of these 10 (5%) corresponded to SM. All SM patients treated with thrombolytic drugs were functionally independent at 3 months and showed no bleeding complications.

CONCLUSIONS

Occasionally SM patients were treated with IVT. This treatment was not associated with bleeding complications and the prognosis of these patients at three months was favorable.

The midpoint between ventilatory thresholds approaches maximal lactate steady state intensity in amateur cyclists

The aim was to determine whether the midpoint between ventilatory thresholds (MPVT) corresponds to maximal lactate steady state (MLSS). Twelve amateur cyclists (21.0 ± 2.6 years old; 72.2 ± 9.0 kg; 179.8 ± 7.5 cm) performed an incremental test (25 W·min^-1) until exhaustion and several constant load tests of 30 minutes to determine MLSS, on different occasions. Using MLSS determination as the reference method, the agreement with five other parameters (MPVT; first and second ventilatory thresholds: VT1 and VT2; respiratory exchange ratio equal to 1: RER = 1.00; and Maximum) was analysed by the Bland-Altman method. The difference between workload at MLSS and VT1, VT2, RER=1.00 and Maximum was 31.1 ± 20.0, -86.0 ± 18.3, -63.6 ± 26.3 and -192.3 ± 48.6 W, respectively. MLSS was underestimated from VT1 and overestimated from VT2, RER = 1.00 and Maximum. The smallest difference (-27.5 ± 15.1 W) between workload at MLSS and MPVT was in better agreement than other analysed parameters of intensity in cycling. The main finding is that MPVT approached the workload at MLSS in amateur cyclists, and can be used to estimate maximal steady state.

Targeted therapy combined with radiotherapy in non-small-cell lung cancer: a review of the Oncologic Group for the Study of Lung Cancer (Spanish Radiation Oncology Society)

In recent years, major advances in our understanding of the molecular biology of lung cancer, together with significant improvements in radiotherapy technologies, have revolutionized the treatment of non-small cell lung cancer (NSCLC). This has led to the development of new therapies that target molecular mutations specific to each tumor type, acting on the cell surface antigens or intracellular signaling pathways, or directly affecting cell survival. At the same time, ablative dose radiotherapy can be delivered safely in the context of metastatic disease. In this article, the GOECP/SEOR (Oncological Group for Study of Lung Cancer/Spanish Society of Radiation Oncology) reviews the role of new targeted therapies used in combination with radiotherapy in patients with locally advanced (stage III) NSCLC and in patients with advanced, metastatic (stage IV) NSCLC.

Resultados a largo plazo de prótesis de cúbito distal como cirugía de rescate en un caso de técnica de Sauvé-Kapandji fallida

La técnica de Sauvé-Kapandji se emplea como tratamiento de rescate en la patología de la articulación radiocubital distal (ARCD). Los resultados postoperatorios son buenos, aunque a largo plazo pueden surgir complicaciones como dolor, muñón cubital inestable y pérdida de fuerza de prensión. Presentamos un caso de cirugía de rescate de esta técnica mediante prótesis de cúbito distal. A los cuatro años de seguimiento, el paciente presenta desaparición completa del dolor y recuperación de la fuerza de prensión, lo que hace pensar que la prótesis cubital puede ser un buen método de rescate cuando fracasa un Sauvé-Kapandji.

Tratamiento percutáneo de las fracturas de escafoides

Las fracturas de escafoides son las más frecuentes de todos los huesos del carpo suponiendo un 60-70% del total. La mayoría de ellas se localizan a nivel de la cintura. Clásicamente, las fracturas no desplazadas se han tratado de manera conservadora durante largos periodos de inmovilización con férulas u ortesis, obteniéndose buenas tasas de consolidación. Una de las alternativas al tratamiento conservador es la osteosíntesis percutánea con tornillo a compresión; técnica que ha demostrado ser efectiva en el tratamiento de este tipo de fracturas obteniendo excelentes tasas de consolidación, con menor tiempo de recuperación y escaso número de complicaciones relacionadas con el acto quirúrgico. El menor tiempo de inmovilización y la rápida reincorporación del paciente a sus actividades cotidianas ha supuesto un auge de este método frente a la decadencia cada vez mayor del tratamiento ortopédico. El objetivo de este artículo es revisar conceptos actuales en la fijación percutánea del escafoides.

Accuracy of Diffusion-Weighted Imaging in the Diagnosis of Stroke in Patients With Suspected Cerebral Infarct

Background and Purpose—

The accuracy of diffusion-weighted imaging (DWI) for the diagnosis of acute cerebral ischemia among patients with suspected ischemic stroke arriving to an emergency room has not been studied in depth.

Methods—

DWI was performed in 712 patients with acute or subacute focal symptoms that suggested an acute ischemic stroke (AIS), 609 of them with AIS.

Results—

DWI demonstrated a sensitivity of 90% and specificity of 97%, a positive likelihood ratio of 31 and a negative likelihood ratio of 0.1 for detecting AIS. The overall accuracy was 95%. Of those patients who demonstrated abnormal DWI studies, 99.5% were AIS patients, and of those patients with normal DWI studies 63% were stroke mimics.

Conclusions—

DWI is accurate in detecting AIS in unselected patients with suspected AIS; a negative study should alert for nonischemic conditions.

Exclusion criteria for intravenous thrombolysis in stroke mimics: an observational study

BACKGROUND

Stroke mimics (SMs) are frequent in emergency departments (EDs), but are treated infrequently with intravenous recombinant tissue plasminogen activator (rt-PA) thrombolysis. We aimed at identifying the factors that lead to the exclusion of SMs from thrombolytic therapy.

METHODS

Consecutive patients presenting to the ED between December 2004 and March 2011 with symptoms that suggested acute ischemic stroke were included.

RESULTS

Eight hundred forty-two patients were included in this study; 113 (13.4%) were considered SMs; these patients were younger (P = .01), more frequently diabetic (P = .001), arrived later to the ED (P = .03), had lower National Institutes of Health Stroke Scale scores (P < .001), and higher frequencies of negative diffusion-weighted imaging studies (P = .002). The most common causes of cases of SM were toxic metabolic disorders (n = 34 [30.1%]) and seizures (n = 22 [19.5%]). The most frequent cause of consultation was aphasia (n = 43 [37.6%]). SM patients had a total of 152 contraindications for rt-PA, with 34 (30%) patients having >1 contraindication. The most frequent of these were being beyond the therapeutic window for thrombolysis (n = 96) and having deficits not measurable by the National Institutes of Health Stroke Scale or very mild symptoms before the start of rt-PA (n = 37). Twenty-four (21.2%) patients had both contraindications simultaneously. Two patients (1.76%) in the SM group were candidates for rt-PA but did not receive this treatment because they or their family rejected it. Of 729 stroke patients, 87 (11.9%) did receive rt-PA.

CONCLUSIONS

SM patients frequently had exclusion criteria for systemic thrombolysis, the most frequent being presenting beyond the established thrombolytic window.

Transcranial Doppler in a Hispanic-Mestizo population with neurological diseases: a study of sonographic window and its determinants

Between 5% and 37% of patients are not suitable for transtemporal insonation with transcranial Doppler (TCD). This unsuitability is particularly frequent in elderly females and non-Caucasians. We aim to evaluate TCD efficiency in a mixed Hispanic population in Santiago, Chile and to determine whether factors associated with the presence of optimal windows depend exclusively on patient-related elements. Seven hundred forty-nine patients were evaluated with power mode TCD. Optimal temporal windows (TWs) included detection of the middle, anterior, posterior cerebral arteries and terminal carotid. The patient's age and sex, the location of the examination, the time of day, whether the test was conducted on weekends and whether mechanical ventilation was used were recorded. Percentages of optimal windows were calculated. Examinations were deemed ideal if both TWs were optimal. TWs were obtained in 82% of cases. In univariate analyses, male sex (P < 0.001), an age below 60 years (P < 0.0001) and mechanical ventilation (P= 0.04) correlated with ideal TWs. Using logistic regression where dependent variable was a non-ideal window only male sex odds ratio (OR) 2.3 (1.51-3.45) and age below 60 OR 13.8 (7.8-24.6) were statistically significant. Our findings indicate that Hispanic populations have detection rates for TWs similar to Europeans and are affected by patient-related elements.

Towards establishing MS prevalence in Latin America and the Caribbean

A very high prevalence of multiple sclerosis (MS) has been reported in some Western European and North American countries. The few surveys of MS epidemiology in South America reveal lower prevalence rates, implying that susceptibility varies between distinct ethnic groups, thus forming an important determinant of the geographic distribution of the disease. The objective of this study is to review MS prevalence estimates in different Latin American and Caribbean countries. We reviewed surveys of regional MS prevalence from 1991 to 2011. Sources included an online database, authors' reports and proceedings or specific lectures from regional conferences. We obtained a total of 30 prevalence surveys from 15 countries, showing low/medium MS prevalence rates. Both the number and the quality of prevalence surveys have greatly improved in this region over recent decades. This is the first collaborative study to map the regional frequency of MS. Establishment of standardized methods and joint epidemiological studies will advance future MS research in Latin America and the Caribbean.

Incidence of multiple sclerosis in Chile. A hospital registry study

OBJECTIVE

To study the incidence of MS in Chile by examining the hospitalizations across all geographical regions of the country and to examine whether there is a correlation between these rates and the latitude or ultraviolet radiation.

METHODS

This is a descriptive study examining the national registry of hospitalizations because of MS (code G35 in ICD-10) from January 1, 2001, to December 31, 2006. Incidence rates were calculated by gender and geographical region and standardized to the world population estimated for 2010.

RESULTS

A total of 6857 hospitalizations were analyzed. There were 935 individuals; 63.9% were women. The mean incidence rate for 2002-2006 period was 0,90 (95% CI: 0.75-1.05). The annualized incidence rates for regions from North to South were as follows: I Tarapaca 0.54 (95% CI: 0.0-1.21), II Antofagasta 0,93 (0.10-1.75), III Atacama 1.07 (0.0-2.31), IV Coquimbo 0.63 (0.01-1.24), V Valparaiso 0.83 (0.38-1.27), VI O'Higgins 0.72 (0.14-1.30), VII Maule 0.52 (0.06-0.98), VIII BIO BIO 0.81 (0.41-1.21), IX Araucanía 0.43 (0.0-0.86), X Los Lagos 0.91 (0.35-1.46), XI Aysen 0.99 (0.0-2.98), XII Magallanes 3.54 (0.57-6.51), and XIII Metropolitana 1.10 (0.84-1.36). There were no significant correlations between hospitalization rates and latitude, except for region XII. UV radiation levels showed significant differences only for region XII.

CONCLUSION

There is a moderate risk of MS in Chile. The southernmost region showed significantly higher incidence rates than those in the rest of the country (a cluster zone). We did not find any correlation between incidence rates and latitude or UV radiation.

Determinants of time trial performance and maximal incremental exercise in highly trained endurance athletes

Human endurance performance can be predicted from maximal oxygen consumption (Vo(2max)), lactate threshold, and exercise efficiency. These physiological parameters, however, are not wholly exclusive from one another, and their interplay is complex. Accordingly, we sought to identify more specific measurements explaining the range of performance among athletes. Out of 150 separate variables we identified 10 principal factors responsible for hematological, cardiovascular, respiratory, musculoskeletal, and neurological variation in 16 highly trained cyclists. These principal factors were then correlated with a 26-km time trial and test of maximal incremental power output. Average power output during the 26-km time trial was attributed to, in order of importance, oxidative phosphorylation capacity of the vastus lateralis muscle (P = 0.0005), steady-state submaximal blood lactate concentrations (P = 0.0017), and maximal leg oxygenation (sO(2LEG)) (P = 0.0295), accounting for 78% of the variation in time trial performance. Variability in maximal power output, on the other hand, was attributed to total body hemoglobin mass (Hb(mass); P = 0.0038), Vo(2max) (P = 0.0213), and sO(2LEG) (P = 0.0463). In conclusion, 1) skeletal muscle oxidative capacity is the primary predictor of time trial performance in highly trained cyclists; 2) the strongest predictor for maximal incremental power output is Hb(mass); and 3) overall exercise performance (time trial performance + maximal incremental power output) correlates most strongly to measures regarding the capability for oxygen transport, high Vo(2max) and Hb(mass), in addition to measures of oxygen utilization, maximal oxidative phosphorylation, and electron transport system capacities in the skeletal muscle.

Kinetics of electro-oxidation of ammonia-N, nitrites and COD from a recirculating aquaculture saline water system using BDD anodes

The viability of the electro-oxidation technology provided with boron doped diamond (BDD) electrodes for the treatment and reuse of the seawater used in a Recirculating Aquaculture System (RAS) was evaluated in this work. The influence of the applied current density (5-50 A m(-2)) in the removal of Total Ammonia Nitrogen (TAN), nitrite and chemical oxygen demand (COD) was analyzed observing that complete TAN removal together with important reductions of the other considered contaminants could be achieved, thus meeting the requirements for reuse of seawater in RAS systems. TAN removal, mainly due to an indirect oxidation mechanism was described by a second order kinetics while COD and nitrite removal followed zero-th order kinetics. The values of the kinetic constants for the anodic oxidation of each compound were obtained as a function of the applied current density (k(TAN) = 7.86 × 10(-5) · exp(6.30 × 10(-2) J); kNO2 = 3.43 × 10(-2) J; k(COD) = 1.35 × 10(-2) J). The formation of free chlorine and oxidation by-products, i.e., trihalomethanes (THMs) was followed along the electro-oxidation process. Although a maximum concentration of 1.7 mg l(-1) of total trihalomethanes was detected an integrated process combining electrochemical oxidation in order to eliminate TAN, nitrite and COD and adsorption onto activated carbon to remove the residual chlorine and THMs is proposed, as an efficient alternative to treat and reuse the seawater in fish culture systems. Finally, the energy consumption of the treatment has been evaluated.

The Electrochemical Development of Pt(111) Stepped Surfaces and Its Influence on Methanol Electrooxidation

The progress in the preparation of new electrode surfaces by electrochemical treatments exhibiting high faradaic efficiencies towards industrial electrocatalytic processes has gained more attention in today's scientific community. Most of the papers report new catalysts dispersed on different substrates, but some fundamental studies required for electrochemical and physical characterizations are sometimes forgotten. In this paper, we make a full staging of two electrochemical treatments that can be conducted to enhance the electrocatalytic activity of platinum surfaces, such as, electrofacetting through square wave potential programs and constant cathodic polarizations in the net hydrogen evolution region. The cathodic treatment applied at −2 V clearly develops (111) stepped planes similarly to the electrofacetting performed after applying the square wave program between 1.40 V and 0.70 V at 2.5 kHz. The X-ray diffraction patterns of both surfaces as well as on other electrofacetted platinum electrodes are obtained for comparison purposes. Moreover, the electrocatalytic activity towards methanol electrooxidation also exhibits equivalent coulombic efficiencies and 200% higher than on polycrystalline platinum as demonstrated by linear sweep voltammetry and potentiostatic current decays.

Frequency and determinants of poststroke cognitive impairment at three and twelve months in Chile

BACKGROUND

A higher risk of poststroke cognitive impairment (CI) has been reported in Hispanics in a US cohort but has not been systematically studied in Latin America.

OBJECTIVES

Our purpose was to investigate the frequencies and determinants of poststroke CI in the hispano-mestizo population of Santiago, Chile.

METHODS

A prospective study of hospitalized patients aged >60 years admitted with an ischemic or hemorrhagic stroke was conducted. The cognitive status was determined at 3 and 12 months after the stroke by informant questionnaires, neuropsychological testing and clinical diagnosis. Cardiovascular risk factors, brain imaging and stroke features were analyzed using regression models to establish determinants for poststroke CI.

RESULTS

A total of 164 patients (mean age = 72 +/- 7.5 years) were recruited. Out of 122 patients (74%) evaluated at 3 months, 81 (66%) had CI. Out of 101 patients (62%) evaluated at 12 months, 39 (39%) had CI no dementia, and 22 (22%) were demented. The new-onset dementia frequency at 1 year was 16%. Independent determinants for dementia were higher functional impairment at hospital egress (OR = 4.0), left-hemisphere large-vessel infarction (OR = 6.9) and a larger amount of white matter changes (OR = 1.3).

CONCLUSIONS

In this first study on poststroke CI in Latin America, the frequencies and determinants of poststroke CI were similar to those in other cohorts of different ethnic origin.