Dependency and frailty in the older haemodialysis patient.

BACKGROUND: Frailty among older adults undergoing hemodialysis is increasingly prevalent, significantly impacting cognitive function, mobility, and social engagement. This study focuses on the clinical profiles of very older adults in hemodialysis, particularly examining the interplay of dependency and frailty, and their influence on dialysis regimens. METHODS: In this observational, descriptive study, 107 patients aged over 75 from four outpatient centers and one hospital unit were examined over a year. Patient data encompassed sociodemographic factors, dialysis specifics, analytical outcomes, lifestyle elements, and self-reported post-treatment fatigue. Malnutrition-inflammation scale was used to measure the Nutritional status; MIS scale for malnutrition-inflammation, Barthel index for dependency, Charlson comorbidity index; FRIED scale for frailty and the SF12 quality of life measure. RESULTS: The study unveiled that a substantial number of older adults on hemodialysis faced malnutrition (55%), dependency (21%), frailty (46%), and diminished quality of life (57%). Patients with dependency were distinctively marked by higher comorbidity, severe malnutrition, enhanced frailty, nursing home residency, dependency on ambulance transportation, and significantly limited mobility, with 77% unable to walk. Notably, 56% of participants experienced considerable post-dialysis fatigue, correlating with higher comorbidity, increased dependency, and poorer quality of life. Despite varying clinical conditions, dialysis patterns were consistent across the patient cohort. CONCLUSIONS: The older adult cohort, averaging over four years on hemodialysis, exhibited high rates of comorbidity, frailty, and dependency, necessitating substantial support in transport and living arrangements. A third of these patients lacked residual urine output, yet their dialysis regimen mirrored those with preserved output. The study underscores the imperative for tailored therapeutic strategies to mitigate dependency, preserve residual renal function, and alleviate post-dialysis fatigue, ultimately enhancing the physical quality of life for these patients.

Reducing variability in nasal surgery outcomes through computational fluid dynamics and advanced 3D virtual surgery techniques.

Objectives: This study aims to delineate the specific impact of using computational fluid dynamics (CFD) and 3D virtual surgery techniques in otolaryngology surgery, focusing on their roles in enhancing the precision of nasal surgery and optimizing future patient outcomes. The central objective was to assess whether these advanced technologies could reduce variability in surgical approaches and decision-making among specialists, thereby improving the consistency and efficacy of patient care in cases of nasal obstruction. Methods and results: Our methodology involved a detailed analysis of pre- and post-operative scenarios using CFD feedback. Six otolaryngologists participated, employing virtual surgery techniques on two patients with diagnosed nasal obstruction. The CFD analysis focused on quantifying key airflow parameters: right nasal flow rate (QR), left nasal flow rate (QL), flow symmetry (Ф), and bilateral nasal resistance (R). These parameters were meticulously compared before and after the application of CFD feedback to evaluate changes in surgical planning and outcomes. Quantitative analysis revealed a notable decrease in the standard deviation of the measured parameters among the specialists post-CFD feedback, indicating reduced variability in surgical approaches. Specifically, for Patient #1 the standard deviation for QR values dropped from 0.694 L/min to 0.602 L/min, and for QL values from 0.676 L/min to 0.584 L/min, and for Patient #2, the standard deviation for QR values decreased from 2.204 L/min to 0.958 L/min, and for QL values from 2.295 L/min to 1.014 L/min. Moreover, the variability range, represented by the differences between the maximum and minimum values for Ф and R, diminished significantly. Post-operative average values for all parameters showed a convergence towards ideal basal levels, suggesting a more uniform and effective surgical strategy across different surgeons. Conclusions: Both integration of CFD and 3D virtual surgery techniques in otolaryngology can substantially reduce variability in surgical planning and decision-making, ultimately leading to improved patient outcomes. These advanced tools have the potential to standardize the diagnosis and treatment of nasal pathologies, contributing to more effective and consistent care. Future research in this area should focus on larger patient cohorts and further exploration of the potential benefits and applications of CFD and virtual surgery in otolaryngology.

The effect of denaturants on protein thermal stability analyzed through a theoretical model considering multiple binding sites.

A novel mathematical development applied to protein ligand binding thermodynamics is proposed, which allows the simulation, and therefore the analysis of the effects of multiple and independent binding sites to the Native and/or Unfolded protein conformations, with different binding constant values. Protein stability is affected when it binds to a small number of high affinity ligands or to a high number of low affinity ligands. Differential scanning calorimetry (DSC) measures released or absorbed energy of thermally induced structural transitions of biomolecules. This paper presents the general theoretical development for the analysis of thermograms of proteins obtained for n-ligands bound to the native protein and m-ligands bound to their unfolded form. In particular, the effect of ligands with low affinity and with a high number of binding sites (n and/or m > 50) is analyzed. If the interaction with the native form of the protein is the one that predominates, they are considered stabilizers and if the binding with the unfolded species predominates, it is expected a destabilizing effect. The formalism presented here can be adapted to fitting routines in order to simultaneously obtain the unfolding energy and ligand binding energy of the protein. The effect of guanidinium chloride on bovine serum albumin thermal stability, was successfully analyzed with the model considering low number of middle affinity binding sites to the native state and a high number of weak binding sites to the unfolded state.

Active case-finding of pulmonary TB in an urban emergency department.

BACKGROUND: The WHO recommends systematic screening of TB in high TB prevalence settings. We evaluated an active case-finding strategy using sputum screening regardless of symptoms in a high TB prevalence Emergency Department (ED) in Peru.METHODS: This was a cross-sectional study conducted at the Hospital Nacional Dos de Mayo ED, which serves low-income populations in downtown Lima, Peru. Adults presenting to the ED for any reason and able to provide sputum were enrolled. Participants provided one sputum specimen for acid-fast bacilli smear and culture. A second sputum specimen for Xpert® MTB/RIF testing was collected if the patient was admitted to an ED observation unit.RESULTS: Between September 2017 and March 2018, 5,171 individuals who presented to the ED were approached. Of 2,119 individuals able to provide sputum, 78 (3.7%) participants had a positive culture and/or Xpert result and were newly diagnosed with TB, whereas traditional screening using >2-week cough identified 41 (1.9%) cases (3.7% vs. 1.9%; P < 0.001). Twelve TB cases (15.4%) reported no TB symptoms of any duration.CONCLUSION: ED-based active case-finding of pulmonary TB using symptom-neutral sputum screening increased TB identification compared to traditional symptom-based screening. Our results align with current WHO recommendation of systematic screening in high TB prevalence areas, which may include ED settings.

Hormone-Related Cancer and Autoimmune Diseases: A Complex Interplay to be Discovered.

Neoplasic transformation is a continuous process that occurs in the body. Even before clinical signs, the immune system is capable of recognizing these aberrant cells and reacting to suppress them. However, transformed cells acquire the ability to evade innate and adaptive immune defenses through the secretion of molecules that inhibit immune effector functions, resulting in tumor progression. Hormones have the ability to modulate the immune system and are involved in the pathogenesis of autoimmune diseases, and cancer. Hormones can control both the innate and adaptive immune systems in men and women. For example androgens reduce immunity through modulating the production of pro-inflammatory and anti-inflammatory mediators. Women are more prone than men to suffer from autoimmune diseases such as systemic lupus erythematosus, psoriasis and others. This is linked to female hormones modulating the immune system. Patients with autoimmune diseases consistently have an increased risk of cancer, either as a result of underlying immune system dysregulation or as a side effect of pharmaceutical treatments. Epidemiological data on cancer incidence emphasize the link between the immune system and cancer. We outline and illustrate the occurrence of hormone-related cancer and its relationship to the immune system or autoimmune diseases in this review. It is obvious that some observations are contentious and require explanation of molecular mechanisms and validation. As a result, future research should clarify the molecular pathways involved, including any causal relationships, in order to eventually allocate information that will aid in the treatment of hormone-sensitive cancer and autoimmune illness.

Meta-analysis and systematic review of ADGRL3 (LPHN3) polymorphisms in ADHD susceptibility.

The gene encoding adhesion G protein-coupled receptor L3 (ADGRL3, also referred to as latrophilin 3 or LPHN3) has been associated with ADHD susceptibility in independent ADHD samples. We conducted a systematic review and a comprehensive meta-analysis to summarize the associations between the most studied ADGRL3 polymorphisms (rs6551665, rs1947274, rs1947275, and rs2345039) and both childhood and adulthood ADHD. Eight association studies (seven published and one unpublished) fulfilled criteria for inclusion in our meta-analysis. We also incorporated GWAS data for ADGRL3. In order to avoid overlapping samples, we started with summary statistics from GWAS samples and then added data from gene association studies. The results of our meta-analysis suggest an effect of ADGRL3 variants on ADHD susceptibility in children (n = 8724/14,644 cases/controls and 1893 families): rs6551665 A allele (Z score = -2.701; p = 0.0069); rs1947274 A allele (Z score = -2.033; p = 0.0421); rs1947275 T allele (Z score = 2.339; p = 0.0978); and rs2345039 C allele (Z score = 3.806; p = 0.0026). Heterogeneity was found in analyses for three SNPs (rs6551665, rs1947274, and rs2345039). In adults, results were not significant (n = 6532 cases/15,874 controls): rs6551665 A allele (Z score = 2.005; p = 0.0450); rs1947274 A allele (Z score = 2.179; p = 0.0293); rs1947275 T allele (Z score = -0.822; p = 0.4109); and rs2345039 C allele (Z score = -1.544; p = 0.1226). Heterogeneity was found just for rs6551665. In addition, funnel plots did not suggest publication biases. Consistent with ADGRL3's role in early neurodevelopment, our findings suggest that the gene is predominantly associated with childhood ADHD.

[Argentinean consensus guidelines on the identification and clinical care of secondary progressive multiple sclerosis]. / Consenso sobre la identificación y seguimiento de la esclerosis múltiple secundaria progresiva en Argentina.

INTRODUCTION: The identification, diagnosis, follow-up, and treatment of patients with secondary progressive multiple sclerosis (SPMS) show significant differences between health care professionals in Argentina. AIM: To provide consensus recommendations on the management of patients with SPMS in Argentina to optimize patient care. DEVELOPMENT: A panel of expert neurologists from Argentina dedicated to the diagnosis and care of multiple sclerosis patients gathered during 2019 and 2020 to carry out a consensus recommendation on the diagnosis and treatment of SPMS patients in Argentina. To achieve consensus, the methodology of 'formal consensus-RAND/UCLA method' was used. Recommendations were established based on published evidence and the expert opinion. Recommendations focused on how to define SPMS and how to follow SPMS patients. CONCLUSION: The recommendations of this consensus guidelines attempt to optimize the care of SPMS patients in Argentina.

TITLE: Consenso sobre la identificación y seguimiento de la esclerosis múltiple secundaria progresiva en Argentina.Introducción. Existen diferencias significativas en el diagnóstico, la identificación y el seguimiento de pacientes con esclerosis múltiple secundaria progresiva (EMSP) entre los profesionales de la salud a cargo de su tratamiento. Objetivo. Proveer recomendaciones sobre el tratamiento de los pacientes con EMSP en Argentina con el fin de optimizar su cuidado. Desarrollo. Un grupo de neurólogos expertos en esclerosis múltiple de Argentina elaboró un consenso para el tratamiento de pacientes con EMSP en la región mediante metodología de ronda de encuestas a distancia y reuniones presenciales. Se establecieron 33 recomendaciones basadas en la evidencia publicada y en el criterio de los expertos que participaron. Las recomendaciones se enfocaron en el diagnóstico y el seguimiento de los pacientes con EMSP. Conclusión. Las recomendaciones establecidas en el presente consenso permitirían optimizar el cuidado y el seguimiento de los pacientes con EMSP en Argentina.

Not Described Variant of Notch3 Gen for Cadasil Disease.

Autosomal dominant cerebral arteriopathy with subcortical infarctions and leukoencephalopathy (CADASIL), is a genetic disease caused by mutations in the Notch3 gene. More than 170 monogenic mutations leading to the development of CADASIL have been reported. We describe a case of a patient and her family with compatible symptoms of CADASIL disease, in which a variable not yet described in the Notch3 gene was detected, that generates a probably pathogenic change in the protein.

Patient perceptions of a tuberculosis testing program provided in the community pharmacy setting.

OBJECTIVES: This study sought to describe patient experiences and perceptions of a public health initiative designed to improve tuberculosis (TB) testing access using the tuberculin skin test (TST) in a community pharmacy setting. STUDY DESIGN: This was a cross-sectional study. METHODS: A telephonic survey of patients who had received a TST at one of twelve participating community pharmacies between August 2014 and July 2016 was conducted. The 26-question survey was developed by two pharmacists with expertise in TB management and one pharmacy student. Before administration the survey was peer-reviewed for clarity. Potential study patients were identified through TST records at the study pharmacies. English-speaking patients older than 18 years were eligible for study inclusion. Statistical differences in responses based on location were identified using chi-squared test for frequency comparisons with a P-value of <0.05 to determine statistical significance. RESULTS: A total of 1709 patients received a TST during the study period, of whom 431 were contacted and 325 participated, meeting the predetermined representative sample needed of 314 patients. The majority of study patients were female (67.1%) and white (81%). The mean age was 36 years (standard deviation = 14.1). A majority (68.3%) lived <5 miles from the TST pharmacy, while 45.2% of those with a primary care provider (PCP) (61.6% of respondents) lived within 5 miles of the PCP's office. Care was accessible and met patients' testing needs. For most patients (84.6%), the initial and follow-up appointments took < 20 min. Follow-up TST reading rate was 98.5%; 4.3% of tests were positive. Positive TST results were associated with use of a small city pharmacy (P = 0.003). Perception differences based on location were identified. CONCLUSIONS: Uptake of the TST service in the community pharmacy setting was high and patients reported positive experiences.

[Argentinean consensus guidelines on the use of monoclonal antibodies in patients with migraine]. / Consenso sobre el uso de anticuerpos monoclonales en la migraña en Argentina.

INTRODUCTION: Migraine is a very prevalent disorder that is estimated to affect about 15% of adult subjects. Recently, the efficacy and safety of monoclonal antibodies that act on the calcitonin gene-related peptide pathway (MA-CGRP) has been evaluated in migraine. Several groups around the world have developed consensus guidelines about the use of monoclonal antibodies, however, in some regions is difficult to extrapolate the recommendations. AIM: To provide recommendations for the use of MA-CGRP in migraine in Argentina. DEVELOPMENT: A group of neurology experts from Argentina, by using the online surveys methodology as well as face to face meetings developed the intended consensus for the use of MA-CGRP in migraine in Argentina. Recommendations were established based on published evidence and the expert opinion. Recommendations focused on how, when, treatment duration and patients follow up. CONCLUSION: The recommendations of this consensus guidelines attempt to optimize the use of MA-CGRP in migraine in Argentina.

TITLE: Consenso sobre el uso de anticuerpos monoclonales en la migraña en Argentina.Introducción. La migraña es un trastorno muy prevalente que se estima que afecta a alrededor del 15% de los sujetos adultos. Durante los últimos años, se ha evaluado la eficacia y la seguridad de los anticuerpos monoclonales que actúan sobre la vía del péptido relacionado con el gen de la calcitonina (AM-PRGC) en la migraña. Diversos grupos de trabajo internacionales han intentado clarificar y normatizar el uso de estos medicamentos en la migraña. Sin embargo, en muchas ocasiones se extrapolan datos de otras regiones que no contemplan la realidad de cada lugar o son difíciles de implementar. Objetivo. Proveer recomendaciones sobre el uso de AM-PRGC en pacientes con migraña en Argentina. Desarrollo. Un grupo de expertos de Argentina conformado por neurólogos, mediante metodología de ronda de encuestas en la distancia y reuniones presenciales, llevó adelante la elaboración del consenso pretendido para el uso de AM-PRGC en pacientes con migraña en Argentina. Se establecieron las recomendaciones basadas en la evidencia publicada y en el criterio de los expertos que participaron. Las recomendaciones se enfocaron en el momento de usar los AM-PRGC en la migraña tanto crónica como episódica, la duración, los cuidados y el entorno para hacerlo. Conclusión. Las recomendaciones establecidas en el presente consenso permitirán optimizar el manejo de los AM-PRGC en pacientes con migraña en Argentina.

ADHD Endophenotypes in Caribbean Families.

Objective: The aim of this study is to contrast the genetics of neuropsychological tasks in individuals from nuclear families clustering ADHD in a Caribbean community. Method: We recruited and clinically characterized 408 individuals using an extensive battery of neuropsychological tasks. The genetic variance underpinning these tasks was estimated by heritability. A predictive framework for ADHD diagnosis was derived using these tasks. Results: We found that individuals with ADHD differed from controls in tasks of mental control, visuospatial ability, visuoverbal memory, phonological and verbal fluency, verbal and semantic fluency, cognitive flexibility, and cognitive ability. Among them, tasks of mental control, visuoverbal memory, phonological fluency, semantic verbal fluency, and intelligence had a significant heritability. A predictive model of ADHD diagnosis using these endophenotypes yields remarkable classification rate, sensitivity, specificity, and precision values (above 80%). Conclusion: We have dissected new cognitive endophenotypes in ADHD that can be suitable to assess the neurobiological and genetic basis of ADHD.

Poly(3-hydroxi-butyrate-co-3-hydroxy-valerate) (PHB-HV) microparticles loaded with holmium acetylacetonate as potential contrast agents for magnetic resonance images.

INTRODUCTION: Biodegradable polymers that contain radioactive isotopes such as Holmium 166 have potential applications as beta particle emitters in tumor tissues. Also, Ho(III) is paramagnetic, which makes it suitable as a contrast agent for magnetic resonance (MR) images. METHODS: Holmium acetylacetonate (Ho(acac)3) loaded poly(3-hydroxy-butyrate-co-3-hydroxy-valerate) microspheres, with 5% or 8% of 3-hydroxy-valerate (HV), were prepared by emulsification/evaporation process within 20-53 µm size. Microspheres characterization was done using scanning electron microscopy, energy-dispersive X-ray, and infrared spectroscopies. The release of holmium(III) in sodium phosphate buffer (pH 7.4) was followed for 9 days with inductively coupled plasma. Finally, T2 and T2* magnetic resonance images (MRI) were acquired and compared with the MRI of the inclusion complex of holmium acetylacetonate in some ß-cyclodextrins. RESULTS: Holmium acetylacetonate loading, evaluated by thermogravimetry, was up to 20 times higher for copolymer with 5% of HV. It was shown that microspheres loaded with Ho(acac)3 exhibited an accumulation of Ho(III) on their surfaces but were stable over time, as no expressive release of holmium(III) was detected in 9-day exposition to sodium phosphate buffer. Holmium acetylacetonate in both microspheres or inclusion complexes was very efficient in obtaining T2 and T2* weighted images in magnetic resonance, thus, might be used as contrast agents. CONCLUSION: This is the first description of the use of inclusion complexes of holmium acetylacetonate in biodegradable polymers as contrast agents. New investigations are underway to evaluate the resistance of PHB-HV polymer microparticles to nuclear activation to assess their potential for use as radiopharmaceuticals for the treatment of liver cancer.

Dual substrate/solvent- roles of water and mixed reaction-diffusion control of ß-Galactosidase catalyzed reactions in PEG-induced macromolecular crowding conditions.

Here we studied the effect of molecular crowding on the hydrolysis of ortho- and para-nitrophenyl-ß-D-galactopyranosides (ONPG, PNPG) catalysed by Escherichia coli ß-Galactosidase in the presence of 0-35%w/v 6kD polyethyleneglycol (PEG6000). The Eadie-Hofstee data analysis exhibited single straight lines for PNPG at all [PEG6000] as well as for ONPG in the absence of PEG6000 so a Michaelian model was applied to calculate the kinetic parameters KM and kcat (catalytic rate constant) values. However, for ONPG hydrolysis in the presence of PEG6000, the two slopes visualized in Eadie-Hofstee plots leaded to apply a biphasic kinetic model to fit initial rate vs. [ONPG] plots hence calculating two apparent KM and two kcat values. Since the rate limiting-step of the enzymatic hydrolysis mechanism of ONPG, but not of PNPG, is the water-dependent one, the existence of several molecular water populations differing in their energy and/or their availability as reactants may explain the biphasic kinetics in the presence of PEG6000. With PNPG, KM as well as kcat varied with [PEG6000] like a parabola opening upward with a minimum at 15 %w/v [PEG6000]. In the case of ONPG, one of the components became constant while the other component exhibited a slight increasing tendency in kcat plus high and [PEG6000]-dependent increasing KM values. Sedimentation velocity analysis demonstrated that PEG6000 impaired the diffusion of ß-Gal but not that of substrates. In conjunction, kinetic data reflected complex combinations of PEG6000-induced effects on enzyme structure, water structure, thermodynamic activities of all the chemical species participating in the reaction and protein diffusion.

ß-sheet to α-helix conversion and thermal stability of ß-Galactosidase encapsulated in a nanoporous silica gel.

The effect on protein conformation and thermal stability was studied for ß-Galactosidase (ß-Gal) encapsulated in the nanopores of a silicate matrix (Eß-Gal). Circular dichroism spectra showed that, compared with the enzyme in buffer (Sß-Gal), Eß-Gal exhibited a higher content of α-helix structure. Heating Eß-Gal up to 75 °C caused a decrease in the content of ß-sheet structure and additional augments on Eß-Gal components attributed to helical content, instead of the generalized loss of the ellipticity signal observed with Sß-Gal. Steady state fluorescence spectroscopy analysis evidenced an Eß-Gal structure less compact and more accessible to solvent and also less stable against temperature increase. While for Sß-Gal the denaturation midpoint (Tm) was 59 °C, for Eß-Galit was 48 °C. The enzymatic activity assays at increasing temperatures showed that in both conditions, the enzyme lost most of its hydrolytic activity against ONPG at temperatures above 65 °C and Eß-Gal did it even at lower T values. Concluding, confinement in silica nanopores induced conformational changes on the tertiary/cuaternary structure of Eß-Gal leading to the loss of thermal stability and enzymatic activity.

Multiple sclerosis prevalence in Salta City, Argentina.

INTRODUCTION: Multiple Sclerosis (MS) is one of the leading causes of disability in young adults. Its prevalence varies according to different countries. In Argentina there is a wide heterogeneity regarding data published in different areas of the country. Prevalence established in most studies is 17 cases per 100,000 inhabitants; however, most of the available data comes from studies that took place in Buenos Aires. There is little or no information from other provinces, especially from Northwest of Argentina (NOA), where there are no studies of the disease prevalence. The aim of this study is to investigate MS prevalence, phenotypes and epidemiological characteristics in Salta, Argentina, in order to contribute to the current knowledge of MS epidemiology and distribution in our country. METHODS: A descriptive, observational, transversal study was carried out in the capital city of Salta. Researchers from all public and private hospitals with a Neurology Department have participated. Private researchers who are well known leaders in demyelinating diseases in the city provided valuable information. Patients who did not have medical control for the past two years as well as patients whose last address was not registered in Salta were excluded. RESULTS: 120 registries were obtained from the four hospitals that participated and from the 12 private researchers. Ten patients were excluded due to overlapping data. The population of the area based on 2010 census was 535,310, so we estimated an MS prevalence 23.8 cases per 100,000 inhabitants (95% CI 20.1-27.4), 24.1 cases per 100,000 inhabitants in female population (95% CI 21.2-28.6) and 18.2 cases per 100,000 inhabitants (95% CI 15.2-21.1) in male population. In our analysis, 64 (58.2%) were female and the average age was 42.1 years. 81.8% are recurrent remitting forms, 16.4% secondary progressive and 1.8% primary progressive. CONCLUSION: This is the first study that provides epidemiological data on the prevalence and clinical forms of MS in Salta City as well as in the entire Northwest Region of Argentina(NOA). We estimate a prevalence of 23.8 cases per 100,000 inhabitants, which establishes a moderate risk area for MS.

A CFD approach to understand nasoseptal perforations.

INTRODUCTION: Nasoseptal perforations (NSP) are becoming common in the modern world, and can cause a wide variety of symptoms, including a sensation of nasal obstruction, epistaxis, crusting, dryness, headache, nasal pain and a whistling sound. There is an extensive range of surgical treatment techniques, but reported results were rarely statistically significant. The lack of consistent surgical results may be related to the lack of knowledge about the pathophysiology of NSP and how they affect the nasal flow. Computational fluid dynamics (CFD) has proved to be a very useful tool to study nasal function. METHODS: We have used CFD software (the program MECOMLAND® and the Digbody® tool for virtual surgery) to investigate the behaviour of the parameters R-[Formula: see text] based on CFD results, when four subjects underwent virtual surgery to induce a septal perforation: two subjects with healthy noses and two patients suffering from nasal airway obstruction. For each case a CFD study was performed, before and after creating an anterior (close to nostrils) or a posterior (close to choanae) NSP. RESULTS: In all cases analyzed, a posterior septal perforation did not result in a significant volumetric flow rate [Formula: see text] through the perforation between nasal passages. However, for anterior defects only in those nasal cavities considered diseased or unhealthy, high values of [Formula: see text] were found. CONCLUSION: The induced NSP only rendered significant flow alterations in noses with preexisting nasal airway obstruction alterations, whereas in nasal cavities considered as normal the creation of a NSP did not produce significant differences between both sides. We strongly suggest that this finding can explain the variety of symptoms and the number of asymptomatic patients bearing NSP.