Validation of Visual Analogue Scale for loss of smell as a quick test in chronic rhinosinusitis with nasal polyps.

BACKGROUND AND OBJECTIVE: Diagnostic criteria of chronic rhinosinusitis with nasal polyps (CRSwNP) include, among others, olfactory dysfunction (OD). We hypothesize that patients suffering with CRSwNP are good at self-assessing their sense of smell through visual analogue scale (VAS) compared to smell tests. METHODS: A controlled cross-sectional study was planned. Adults diagnosed with severe CRSwNP waiting for endoscopic sinus surgery were included. A cohort of healthy controls was also studied. All participants performed Barcelona smell test (BAST-24), sinonasal outcomes test 22 (SNOT-22), and VAS for loss of smell. CRSwNP underwent blood test (eosinophils count, total serum IgE), CT scan (Lund-Mackay Score), and nasal endoscopy. RESULTS: 138 severe CRSwNP and 40 controls subjects were included. The BAST-24 identification score was strongly correlated with the VAS score in the CRSwNP group (rho=-0.79, p<0.001) but not in the control group (rho=-0.14; p=0.39), this difference between groups being statistically significant (p<0.001). A significant correlation of SNOT-22 item 21 (loss of smell) was also found with BAST-24 identification (rho=-0.65, p<0.001), this difference being statistically significant (Z=-2.43; p=0.015). In the ROC curve, the area under the curve (AUC) was 0.85 with 72.5% sensitivity and 93.1% specificity. CONCLUSION: This study demonstrates a potential role of the VAS score for the screening of OD in severe CRSwNP in daily clinical practice.

Smell and Taste Dysfunction in COVID-19 Is Associated With Younger Age in Ambulatory Settings: A Multicenter Cross-Sectional Study.

BACKGROUND AND OBJECTIVE: Since the initial anecdotal reports of coronavirus disease 2019 (COVID-19) from China, a growing number of studies have reported on smell and/or taste dysfunction (STD). Objective: The aim of our study was to investigate the frequency and severity of STD in COVID-19 patients and to evaluate the association with demographic characteristics, hospital admission, symptoms, comorbidities, and blood biomarkers. METHODS: We performed a multicenter cross-sectional study on patients who were positive for SARS-CoV-2 (n=846) and controls (n=143) from 15 Spanish hospitals. Data on STD were collected prospectively using an in-person survey. The severity of STD was categorized using a visual analog scale. We analyzed time to onset, recovery rate, time to recovery, hospital admission, pneumonia, comorbidities, smoking, and symptoms. RESULTS: STD was at least 2-fold more common in COVID-19-positive patients than in controls. COVID-19-positive hospitalized patients were older, with a lower frequency of STD, and recovered earlier than outpatients. Analysis stratified by severity of STD showed that more than half of COVID-19 patients presented severe loss of smell (53.7%) or taste (52.2%); both senses were impaired in >90%. In the multivariate analysis, older age (>60 years), being hospitalized, and increased C-reactive protein were associated with a better sense of smell and/or taste. COVID-19-positive patients reported improvement in smell (45.6%) and taste (46.1%) at the time of the survey; in 90.6% this was within 2 weeks of infection. CONCLUSION: STD is a common symptom in COVID-19 and presents mainly in young and nonhospitalized patients. More studies are needed to evaluate follow-up of chemosensory impairment.

Towards an optimal treatment algorithm for metastatic pancreatic ductal adenocarcinoma (PDA).

Chemotherapy remains the mainstay of treatment for advanced pancreatic ductal adenocarcinoma (pda). Two randomized trials have demonstrated superiority of the combination regimens folfirinox (5-fluorouracil, leucovorin, oxaliplatin, and irinotecan) and gemcitabine plus nab-paclitaxel over gemcitabine monotherapy as a first-line treatment in adequately fit subjects. Selected pda patients progressing to first-line therapy can receive secondline treatment with moderate clinical benefit. Nevertheless, the optimal algorithm and the role of combination therapy in second-line are still unclear. Published second-line pda clinical trials enrolled patients progressing to gemcitabine-based therapies in use before the approval of nab-paclitaxel and folfirinox. The evolving scenario in second-line may affect the choice of the first-line treatment. For example, nanoliposomal irinotecan plus 5-fluouracil and leucovorin is a novel second-line option which will be suitable only for patients progressing to gemcitabine-based therapy. Therefore, clinical judgement and appropriate patient selection remain key elements in treatment decision. In this review, we aim to illustrate currently available options and define a possible algorithm to guide treatment choice. Future clinical trials taking into account sequential treatment as a new paradigm in pda will help define a standard algorithm.

Systemic lupus erythematosus impairs memory cognitive tests not affected by depression.

OBJECTIVE: Our aim was to assess the contribution of depression to cognitive impairment in patients with systemic lupus erythematosus (SLE). METHODS: Clinical features, education, age, and Hospital Anxiety and Depression Scale (HADS) were evaluated in 82 patients with SLE and 22 healthy controls, all Chilean women. The Cambridge Neuropsychological Test Automated Battery (CANTAB eclipseTM) assessing attention, spatial memory, and learning and executive function domains was applied. Cognitive deficit definition: a cut-off for definite impairment was defined as a score below -2 standard deviations in at least one outcome measure in two or more domains. ANCOVA with stepwise selection evaluated influences of health status (SLE or control), age, education, and HADS depression and anxiety scores on cognitive outcomes. To avoid overfitting, a shrinkage method was performed. Also, adjusted p-values for multiple comparisons were obtained. RESULTS: Cognitive deficit affected 16 (20%) patients, and no controls (p=0.039). Median HADS depression score in SLE patients was 6 (range 0-19) and in controls was 0 (0-19), p<0.001). ANCOVA and shrinkage models showed that worse cognitive performance in sustained attention and spatial working memory tests was explained by the presence of SLE but not depression, whereas depression only affected a measure of executive function (I/ED Stages completed). CONCLUSION: Depression has a limited role in cognitive impairment in SLE. Impairments in sustained attention and spatial working memory are distinctly influenced by yet-unknown disease-intrinsic factors.

[Parental perceptions and expectations about sexual and reproductive health care for urban adolescents]. / Madres y padres de adolescentes urbanos: percepciones y expectativas de la atención en salud sexual y reproductiva para sus hijos.

UNLABELLED: Studies have reported which expectations and demands adolescents have for more accessible sexual and reproductive health (SRH) services. However, there is limited information regarding parents' requirements and demands for SRH services their adolescents need. AIM: To explore the knowledge of parents regarding SRH needs of their adolescent daughters and sons and what they demand from primary health care services (PHCS). MATERIAL AND METHODS: A quali-quantitative, descriptive, cross-sectional study was performed. Nine fathers and 24 mothers were interviewed to design a survey. In the quantitative phase, 125 mothers voluntarily, anonymously and confidentially were interviewed. All participants were users of PHCS of urban communities in the Metropolitan Area showing a high percentage of births by adolescents' mothers. Data analysis was descriptive and analytical. RESULTS: Interviews served as input to design the questionnaire. Seventy seven percent (77,6%) of interviewed mothers knew that their sons/daughters, regardless of their gender, had concern about sexuality; their main fear was adolescent pregnancy. Seventy six percent (76%) was aware that their sons/daughters might request attention in SRH clinics and 97% agreed that they should require these services during early adolescence. The most desirable features of such services were identified. CONCLUSIONS: Parents recognize that they would prefer their sons/daughters postponed sexual initiation; however, they are aware that pregnancy prevention is needed. Mothers approve SRH services. They agree that counseling to prevent pregnancies and sexual transmitted diseases (STD) and AIDS was an important issue. They require support for themselves and their sons/daughters.

Myelin Oligodendrocyte Glycoprotein Antibody-associated Disease and an Incidental Thyroid Nodule.

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare, immune-mediated demyelinating disease of the central nervous system (CNS) that has a predilection for children. Its association with malignancy or other autoimmune diseases is unclear. We present a case of MOGAD in a teenager with a coincidental thyroid malignancy and elevated intracranial pressure.

Papilledema as a possible key sign for diagnosis of cryopyrin-associated periodic syndromes (CAPS): A case report.

Cryopyrin-associated periodic syndrome is a rare and probably underdiagnosed disease. It presents with various systemic manifestations, including ophthalmological, making its diagnosis a challenge for the clinician. We present the case of a 4-year-old girl for which the identification of papilledema in the ophthalmological examination was the key sign for the diagnosis of cryopyrin-associated periodic syndrome. Our aim is to raise awareness of this syndrome with serious implications for affected patients, so that it is taken into account more frequently as a differential diagnosis, allowing an early diagnosis.

Pediatric maxillary expansion has a positive impact on hearing? A systematic review and meta-analysis.

OBJECTIVE: Hearing loss is a highly prevalent condition in the pediatric population. Pediatric maxillary expansion is a widespread treatment to address transverse maxillary deficiency. First reports describing an association between improvements for patients with HL and PME initiated in the 1960s. In this systematic review and meta-analysis we aim to review the role of maxillary expansion in reducing conductive hearing loss in pediatric population. REVIEW METHODS: Pubmed (Medline), the Cochrane Library, EMBASE and Trip Database were checked. Main outcome was expressed as the difference between air-bone gap, compliance, ear volume and conductive hearing thresholds before and after treatment and the 95% confidence interval. RESULTS: A total of 10 studies (218 patients) met inclusion criteria. The pooled data in the meta-analysis under a random effects model shows a statistically significant difference of 10.57dB mean reduction after palatal expansion. The air-bone gap was significantly reduced by 5.39dB (CI 95% 3.68, 7.10). Compliance and volume were assessed in three studies, with a non-significant positive difference in the compliance (0.14) and a statistically significant difference for volume (0.80) after palatal expansion. CONCLUSION: This systematic review and meta-analysis found a positive effect of pediatric maxillary expansion in conductive hearing loss in well-select children. However, results cannot be extrapolated for children with conductive hearing loss without an accompanying orthodontic indication (maxillary constriction). It showed that the existing prospective studies exhibited qualitative pitfalls, limiting the ability to obtain conclusive evidence about the role of pediatric maxillary expansion on conductive hearing loss in children.

Improving heat and moisture exchanger therapy with a hydrogel base adhesive in laryngectomised patients: an open, randomised, crossover trial.

OBJECTIVE: This study aimed to assess individual preference, symptoms and compliance between habitual use of Provox XtraFlow and the combination of Provox XtraFlow during the day and Provox Luna during the night for heat and moisture exchanger therapy in laryngectomised patients. METHOD: This was an open, randomised, crossover trial for 25 days. After this first study period and a 5-day wash-out period, treatments were switched for another 25 days. RESULTS: A total of 28 patients were enrolled. Differences were found (p = 0.009) in the incidence of dermatological problems with XtraFlow (46.4 per cent) versus Provox Luna (14.3 per cent), as well as in the need to abandon the use of adhesives (46.4 per cent vs 10.7 per cent; p = 0.003). A total of 60.7 per cent of the patients preferred the Provox Luna system as their preference for heat and moisture exchanger therapy. CONCLUSION: The Provox Luna system is a viable additive to heat and moisture exchanger therapy, especially in the setting of compliance concerns and in patients who desire dermatological relief overnight.

Common mental disorders and psychological distress in systemic lupus erythematosus are not associated with disease activity.

Psychiatric diagnosis in patients with systemic lupus erythematosus (SLE) is controversial: variations have been reported in frequency, diagnostic assays, associations with disease activity, autoantibodies, and contributing social factors. Eighty-three consecutive non-selected Chilean patients with SLE were evaluated for: (i) 26 common mental disorders according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), using the Mini-International Neuropsychiatric Interview (MINI-plus); (ii) psychological suffering measured by Hospital Anxiety and Depression Scale (HADS); (iii) ACR 1999 neuropsychiatric (NP)SLE criteria; (iv) SLE disease activity (SLEDAI-2K); (v) cumulative damage (SLICC/ACR); and (vi) anti-ribosomal P antibodies by enzyme-linked immunoassay and immunoblot. Psychiatric diagnoses occurred in 44.6% of patients; the most frequent (21.7%) was major depressive episode (MDE). No association with lupus activity was observed in patients with a DSM-IV diagnosis or MDE or psychological suffering. ACR 1999 NPSLE criteria were present in 42.2% of patients, the majority corresponding to mood (28.9%) or anxiety disorders (15.6%). Suicidal risk was present in 9.6% of patients. Anti-ribosomal P antibodies (13.3%) were not associated with DSM-IV diagnosis. Severe psychiatric disorders in SLE are common and not associated with disease activity.

Thresholds for Transverse Stimulation: Fiber Bundles in a Uniform Field.

Cable theory is used to model fibers (neural or muscular) subjected to an extracellular stimulus or activating function along the fiber (longitudinal stimulation). There are cases however, in which activation from fields across a fiber (transverse stimulation) is dominant and the activating function is insufficient to predict the relative stimulus thresholds for cells in a bundle. This work proposes a general method of quantifying transverse extracellular stimulation using ideal cases of long fibers oriented perpendicular to a uniform field (circular cells in a 2-D extracellular domain). Several methods are compared against a fully coupled model to compute electrical potentials around each cell of a bundle and predict the magnitude of applied plate potential (Öp) needed to activate a given cell (Öpact). The results show that with transverse stimulation, the effect of cell presence on the external field must be considered to accurately compute Öpact. They also show that approximating cells as holes can accurately predict firing order and Öpact of cells in bundles. Potential profiles from this hole model can also be applied to single cell models to account for time-dependent transmembrane voltage responses and more accurately predict Öpact. The approaches used herein apply to other examples of transverse cell stimulation where cable theory is inapplicable and coupled model simulation is too costly to compute.

Unconstrained parameter estimation for assessment of dynamic cerebral autoregulation.

Measurement of dynamic cerebral autoregulation (CA), the transient response of cerebral blood flow (CBF) to changes in arterial blood pressure (ABP), has been performed with an index of autoregulation (ARI), related to the parameters of a second-order differential equation model, namely gain (K), damping factor (D) and time constant (T). Limitations of the ARI were addressed by increasing its numerical resolution and generalizing the parameter space. In 16 healthy subjects, recordings of ABP (Finapres) and CBF velocity (ultrasound Doppler) were performed at rest, before, during and after 5% CO(2) breathing, and for six repeated thigh cuff maneuvers. The unconstrained model produced lower predictive error (p < 0.001) than the original model. Unconstrained parameters (K'-D'-T') were significantly different from K-D-T but were still sensitive to different measurement conditions, such as the under-regulation induced by hypercapnia. The intra-subject variability of K' was significantly lower than that of the ARI and this parameter did not show the unexpected occurrences of zero values as observed with the ARI and the classical value of K. These results suggest that K' could be considered as a more stable and reliable index of dynamic autoregulation than ARI. Further studies are needed to validate this new index under different clinical conditions.

Tamoxifen induces apoptotic neutrophil efferocytosis in horses.

Macrophages and neutrophils are important cellular components in the process of acute inflammation and its subsequent resolution, and evidence increasingly suggests that they play important functions during the resolution of chronic, adaptive inflammatory processes. Exacerbated neutrophil activity can be harmful to surrounding tissues; this is important in a range of diseases, including allergic asthma and chronic obstructive pulmonary disease in humans, and equine asthma (also known as recurrent airway obstruction (RAO). Tamoxifen (TX) is a non-steroidal estrogen receptor modulator with effects on cell growth and survival. Previous studies showed that TX treatment in horses with induced acute pulmonary inflammation promoted early apoptosis of blood and BALF neutrophils, reduction of BALF neutrophils, and improvement in animals' clinical status. The aim of this study was to describe if TX induces in vitro efferocytosis of neutrophils by alveolar macrophages. Efferocytosis assay, myeloperoxidase (MPO) detection and translocation phosphatidylserine (PS) were performed on neutrophils isolated from peripheral blood samples from five healthy horses. In in vitro samples from heathy horses, TX treatment increases the phenomenon of efferocytosis of peripheral neutrophils by alveolar macrophages. Similar increases in supernatant MPO concentration and PS translocation were observed in TX-treated neutrophils, compared to control cells. In conclusion, these results confirm that tamoxifen has a direct effect on equine peripheral blood neutrophils, through stimulation of the engulfment of apoptotic neutrophils by alveolar macrophages.

Unusual Sequence of Events in a Case of Takotsubo Syndrome.

A 73-year-old female with multiple comorbidities including coronary artery disease was admitted for an elective PCI of a lesion detected in the RCA. On the day of the planned PCI, shortly after right femoral artery cannulation, the patient developed a sudden complete heart block requiring the administration atropine and insertion of a temporary pacemaker. Concomitantly, the patient developed acute pulmonary edema, hypotension, and hypoxia requiring intubation for mechanical ventilation. Vasopressors were administered. A coronary angiogram showed patent left and right coronary arteries, unchanged when compared to the previous angiogram. An echocardiogram performed in the cardiac catheterization lab revealed global hypokinesis of the left and right ventricles, with severe LV systolic dysfunction (EF < 20%). Following an insertion of an intra-aortic balloon pump, the patient was transferred to the CICU. A repeat echocardiogram in the CICU two hours later revealed a classical echocardiographic presentation of Takotsubo syndrome, apical hypokinesis. By the next morning the patient's hemodynamic status significantly improved, the balloon pump was removed, and vasopressors were discontinued. Another echocardiogram was performed 24 hours after the event occurred and revealed a marked improvement in LV systolic function (EF 60%), with complete resolution of apical and septal wall motion abnormalities. Three days after the event, the patient was successfully discharged and asymptomatic at two-month follow-up. This case illustrates an atypical presentation of Takotsubo syndrome that was witnessed from onset to its complete resolution during the patient's hospital stay.

Abordaje endoscópico extendido del seno frontal: Experiencia en Hospital Clínico Universidad de Chile / Extended endoscopic approach of the frontal sinus: Experience at Hospital Clínico Universidad de Chile

Introducción: El seno frontal es una estructura compleja y desafiante en términos quirúrgicos, siendo descritas numerosas técnicas para su abordaje. Dentro de ellas se destaca el abordaje endoscópico extendido de seno frontal: Draf IIB y Draf III, como una importante alternativa para resolución de patología refractaria de seno frontal. Objetivo: Describir las características de pacientes sometidos a abordaje endoscópico extendido de seno frontal en Hospital Clínico Universidad de Chile (HCUCH). Material y Método: Estudio retrospectivo, descriptivo. Se incluyeron a pacientes sometidos a abordaje endoscópico extendido de seno frontal entre los años 2013 y 2021. Se analizaron variables clínicas, intraoperatorias y de seguimiento. Resultados: Se registraron 118 pacientes, de los cuales 64 cumplieron criterios de inclusión al estudio, con una edad promedio de 48 años. La patología más frecuente fue la rinosinusitis crónica poliposa (42%) seguido del mucocele (20%). Del total de pacientes, el 68% fue sometido a cirugía Draf IIB y el resto a Draf III. Todos los pacientes fueron estudiados con endoscopía e imágenes, y seguidos con parámetros clínicos y endoscópicos. El porcentaje de estenosis postoperatoria se estimó en 10%. Conclusión: El abordaje endoscópico nasal extendido figura como una alternativa útil para manejo de patología de seno frontal refractario a tratamiento. En nuestra experiencia las indicaciones, tipos de cirugía y tasa de complicaciones son concordantes con la literatura internacional.

Introduction: The frontal sinus is a complex and challenging structure in surgical terms, numerous techniques have been described for its approach, among them the extended endoscopic approach: Draf IIB and Draf III, figures as an important alternative for the resolution of refractory pathology of frontal sinus. Aim: To describe the characteristics of patients who underwent an extended endoscopic approach to the frontal sinus at the Hospital Clínico Universidad de Chile (HCUCH). Material and Method: A retrospective, descriptive study included patients who underwent an extended endoscopic approach to the frontal sinus between 2013 and 2021. Clinical, intraoperative, and follow-up variables were analyzed. Results: 118 patients were registered, of which 64 met the inclusion criteria for the study, with an average age of 48 years. The most frequent pathology was chronic polypous rhinosinusitis (42%), followed by mucocele (20%). Of the patients, 68% underwent Draf IIB surgery, while the rest received a Draf III type procedure. All patients were studied with endoscopy and images and followed up with clinical and endoscopic parameters. The percentage of post operatory stenosis was 10%. Conclusion: The extended nasal endoscopic approach appears as a valuable alternative for managing frontal sinus pathology refractory to treatment. In our experience, the indications, types of surgery, and rate of complications are consistent with the international literature.

Thyroid function in a uremic rat model. Evidence suggesting tissue hypothyroidism.

The main objective of this study was to determine whether the principal abnormality of thyroid function observed in patients with chronic renal failure, low serum triiodothyronine (T(3)) concentration, causes hypothyroidism at the tissue level. A partially nephrectomized (Nx) uremic rat model was developed and the following parameters of thyroid function were assessed: serum total thyroxine (TT(4)), total T(3) (TT(3)), and thyrotropin and liver T(3) content, and activity of two thyroid hormone-dependent enzymes, mitochondrial alpha-glycerophosphate dehydrogenase (alpha-GPD) and cytosol malate dehydrogenase (MDH). The results were compared to those of intact control (C), thyroidectomized (Tx), and nephrectomized-thyroidectomized (NxTx) littermates.Results expressed as mean+/-SEM showed that Nx rats had a fivefold increase in blood urea nitrogen, (112+/-20 mg/dl in Nx, and 22+/-1 mg/dl in C) and manifested all the changes of of thyroid function observed in uremic men, including a low serum TT(3) level (30+/-7 ng/dl in Nx and 50+/-6 ng/dl in C). In the liver, T(3) was significantly reduced (18+/-2 ng/total liver in Nx and 35+/-3 ng/total liver in C) as well as the activities of alphaGPD (8.8+/-1.0 and 16.1+/-1.5 DeltaOD/min per total liver in Nx and C, respectively) and MDH (6.3+/-1.6 and 12.6+/-2.2 U/total liver in Nx and C, respectively). The reduction in liver enzyme activities correlated significantly with the decrease in T(3) content. The changes in Tx rats were as expected, showing a profound reduction in serum hormone levels, liver T(3) content, and liver enzyme activities. Serum thyrotropin was markedly elevated to 2,390+/-212 ng/ml as compared to 703+/-61 in C and 441+/-87 ng/ml in Nx rats. The NxTx rats showed the combined effects of nephrectomy and thyroidectomy; blood urea nitrogen was elevated to 203, and serum levels of TT(4), TT(3), and thyrotropin were 0.4, <10, and 2,525, respectively. Total liver T(3) and alphaGPD and MDH were strikingly low; the corresponding values were 3.5, 2.4, and 2.5.l-triiodothyronine replacement (0.4 mug/100 g body wt/d) for 4 wk in the Nx rats resulted in significant increases in liver enzyme activities, alphaGPD and MDH rose by 70 and 60% over their respective basal values without alteration in the severity of azotemia. From these data, we conclude that the reduction of liver T(3) content in the uremic rats, accompanied by a decrease in alphaGPD and MDH activity, indicates the presence of hypothyroidism at the tissue level. Restoration of enzyme activities toward normal levels after T(3) administration provided further supporting evidence that the diminution in liver enzyme activity was causally related to tissue T(3) deficiency.

An analytical comparison of the information in sorted and non-sorted cosine-tuned spike activity.

Spike sorting is a technologically expensive component of the signal processing chain required to interpret population spike activity acquired in a neuromotor prosthesis. No systematic analysis of the value of spike sorting has been carried out, and little is known about the effects of spike sorting error on the ability of a brain-machine interface (BMI) to decode intended motor commands. We developed a theoretical framework to examine the effects of spike processing on the information available to a BMI decoder. We computed the mutual information in neural activity in a simplified model of directional cosine tuning to compare the effects of pooling activity from up to four neurons to the effects of sorting with varying amounts of spike error. The results showed that information in a small population of cosine-tuned neurons is maximized when the responses are sorted and there is diverse tuning of units, but information was affected little when pooling units with similar preferred directions. Spike error had adverse effects on information, such that non-sorted population activity had 79-92% of the information in its sorted counterpart for reasonable amounts of detection and sorting error and for units with moderate differences in preferred direction. This quantification of information loss associated with pooling units and with spike detection and sorting error will help to guide the engineering decisions in designing a BMI spike processing system.

In Vitro effects of tamoxifen on equine neutrophils.

Neutrophils participate in innate immunity as the first line of host defense against microorganisms. However, exacerbated neutrophil activity can be harmful to surrounding tissues; this is important in a range of diseases, including allergic asthma and chronic obstructive pulmonary disease in humans, and equine asthma (also known as recurrent airway obstruction (RAO). Tamoxifen (TX) is a non-steroidal estrogen receptor modulator with effects on cell growth and survival. Previous preliminary studies showed that TX treatment in horses with induced acute pulmonary inflammation promoted early apoptosis of blood and BALF neutrophils, reduction of BALF neutrophils, and improvement in animals' clinical status. The aim of this study was to evaluate the in vitro effect of TX on functional tests in equine peripheral blood neutrophils. Chemotaxis, respiratory burst production and phagocytosis assays were performed on neutrophils isolated from peripheral blood samples from 10 healthy horses. Results showed that IL-8 stimulated cells decrease their chemotactic index when treated with TX (1 and 10µM). Respiratory burst production was also dampened after treatment with TX. In conclusion, these results confirm that tamoxifen has a direct action on equine peripheral blood neutrophils. However, more in vivo and in vitro studies are required to fully understand the mechanisms of action of TX on neutrophils, in order to elucidate if it can be used as treatment in disorders such as allergic asthma in humans and horses.

A computer model of normal conduction in the human atria.

Although considerable progress has been made in understanding the process of wavefront propagation and arrhythmogenesis in human atria, technical concerns and issues of patient safety have limited experimental investigations. The present work describes a finite volume-based computer model of human atrial activation and current flow to complement these studies. Unlike previous representations, the model is three-dimensional, incorporating both the left and right atria and the major muscle bundles of the atria, including the crista terminalis, pectinate muscles, limbus of the fossa ovalis, and Bachmann's bundle. The bundles are represented as anisotropic structures with fiber directions aligned with the bundle axes. Conductivities are assigned to the model to give realistic local conduction velocities within the bundles and bulk tissue. Results from simulations demonstrate the role of the bundles in a normal sinus rhythm and also reveal the patterns of activation in the septum, where experimental mapping has been extremely challenging. To validate the model, the simulated normal activation sequence and conduction velocities at various locations are compared with experimental observations and data. The model is also used to investigate paced activation, and a mechanism of the relative lengthening of left versus right stimulation is presented. Owing to both the realistic geometry and the bundle structures, the model can be used for further analysis of the normal activation sequence and to examine abnormal conduction, including flutter. The full text of this article is available at http://www.circresaha.org.