The dilution evaluation as a corrective measure for interference in the white blood cell scattergram in Beckman Coulter DxH 900.

BACKGROUND: The Beckman Coulter DxH 900 is a haematological analyser capable of counting and sizing blood cells, and obtaining a complete blood cell count (CBC). This analyses different parameters of red blood cells (RBC), platelets and white blood cells/leukocytes. Some automated CBC counters present limitations due to specimen characteristics, abnormal cells or both factors. In the presence of abnormalities, the DxH 900 has a flagging system, warning the laboratory technician that something needs to be verified. In the present work, we evaluated samples from oncologic patients, presenting a population erroneously perceived as being lymphocytes. The most common explanations for this situation are RBC resistant to lysis or serum hyperbilirubinaemia. METHODS: In an attempt to solve and understand what the cause of this problem might be, we diluted our samples (1:3) and analysed the serum total bilirubin. To identify cells' abnormalities, the samples were also analysed by manual DLC counts. During the study, we also checked the different flags presented by the equipment. RESULTS: The results evidenced that the major interference was due to RBC lysis resistance, corresponding to 94.7% of the cases, while hyperbilirubinaemia was only present in 73.4%. Besides, we determined that some samples with normal bilirubin levels also presented interference, suggesting that hyperbilirubinaemia was not the main cause of the error. The most recurrent flag observed was "High event rate". CONCLUSION: The dilution solved all of the observed interferences. The results between diluted and manual counts showed a strong correlation, leading us to introduce dilution in our laboratory routine.

Skin cancer screening: the experience in South Portugal.

BACKGROUND: The number of skin cancer cases and related deaths continues to increase worldwide, including in Portugal. The lack of efficient health care leaves the southern Portuguese population at risk of presenting skin lesions at later stages. An initiative for skin cancer screening and medical care follow-up was created by the nonprofit organization Liga Portuguesa Contra o Cancro - Núcleo Regional do Sul (LPCC-NRS). METHODS: Information was gathered from 4,398 participants in several Southern Portugal regions, from January 2021 to July 2022. Descriptive and lesion risk statistical analyses were applied. RESULTS: Participants' characteristics were described, and risk assessment was performed differentially between premalignant (n = 577) and malignant lesions (n = 176). The main risk factor for both was male gender. From the described suspicious malignant lesions, 31.8% were confirmed (n = 56), among which there were 43 basal cell carcinomas (BCC), 9 cutaneous melanomas (CM), and 4 squamous cell carcinomas (SCC). CONCLUSIONS: Data analysis pointed to a need for improved participant recruitment, especially of male participants, and health literacy assessment in future screenings.

Adhesions in the setting of hip arthroscopy.

With the growing number of primary arthroscopies performed, patients requiring revision hip arthroscopies for various issues is high including postoperative adhesion formation, a source of pain, mechanical symptoms, range of motion limitation, stiffness, and microinstability. Adhesions are a consequence of biological pathways that have been stimulated by injury or surgical interventions leading to an increased healing response. Preventative efforts have included surgical adjuncts during/after primary hip arthroscopy, biologic augmentation, and postoperative rehabilitation. Treatment options for adhesion formation includes surgical lysis of adhesions with or without placement of biologic membranes aimed at inhibiting adhesion reformation as well as systemic medications to further reduce the risk. Postoperative rehabilitation exercises have also been demonstrated to prevent adhesions as a result of hip arthroscopy. Ongoing clinical trials are further investigating pathways and prevention of adhesion formation.

Cardiopulmonary Exercise Testing in Patients with Heart Failure: Impact of Gender in Predictive Value for Heart Transplantation Listing.

BACKGROUND: Exercise testing is key in the risk stratification of patients with heart failure (HF). There are scarce data on its prognostic power in women. Our aim was to assess the predictive value of the heart transplantation (HTx) thresholds in HF in women and in men. METHODS: Prospective evaluation of HF patients who underwent cardiopulmonary exercise testing (CPET) from 2009 to 2018 for the composite endpoint of cardiovascular mortality and urgent HTx. RESULTS: A total of 458 patients underwent CPET, with a composite endpoint frequency of 10.5% in females vs. 16.0% in males in 36-month follow-up. Peak VO2 (pVO2), VE/VCO2 slope and percent of predicted pVO2 were independent discriminators of the composite endpoint, particularly in women. The International Society for Heart Lung Transplantation recommended values of pVO2 ≤ 12 mL/kg/min or ≤14 if the patient is intolerant to ß-blockers, VE/VCO2 slope > 35, and percent of predicted pVO2 ≤ 50% showed a higher diagnostic effectiveness in women. Specific pVO2, VE/VCO2 slope and percent of predicted pVO2 cut-offs in each sex group presented a higher prognostic power than the recommended thresholds. CONCLUSION: Individualized sex-specific thresholds may improve patient selection for HTx. More evidence is needed to address sex differences in HF risk stratification.

Animal products in neurosurgery - navigating informed consent.

Informed consent is an ethical and legal requirement integral to modern surgical practice. Clinicians have a duty to consider, disclose and discuss risks and concerns relevant to an individual patient. With medical advances there are now a significant number of animal-derived products and adjuncts available for use in modern neurosurgical practice, which may be relevant when consenting patients for specific procedures if such products are used. This paper highlights commonly used products in neurosurgery that contain animal-derived constituents with the aim of facilitating an informed discussion between the neurosurgeon and patient. We have reviewed the commonly used products in the centres of the authors and their commercial equivalents. The product information is taken from the manufacturer's instructions or the Federal Drug Administration documents regarding the product. Animal products commonly available to neurosurgeons can be broadly categorised into haemostatic agents, dural substitutes, dural sealants and bone cements. Many products contain a variety of animal (or human) derived products. In order to ensure informed consent and shared decision making, it is important to establish any relevant patient beliefs or views regarding the use of animal-derived products. Given the wide availability and use of neurosurgical adjuncts containing human or animal derived products, coupled with the heterogeneity within ethnic, religious, and social groups, each patient must be approached individually to ensure patient-specific concerns are identified and alternatives offered when appropriate.

Age Differences in Cardiopulmonary Exercise Testing Parameters in Heart Failure with Reduced Ejection Fraction.

Background and Objectives: Cardiopulmonary exercise testing (CPET) is a cornerstone of risk stratification in heart failure with reduced ejection fraction (HFrEF). However, there is a paucity of evidence on its predictive power in older patients. The aim of this study was to evaluate the prognostic power of current heart transplantation (HTx) listing criteria in HFrEF stratified according to age groups. Materials and Methods: Consecutive patients with HFrEF undergoing CPET between 2009 and 2018 were followed-up for cardiac death and urgent HTx. Results: CPET was performed in 458 patients with HFrEF. The composite endpoint occurred in 16.8% of patients ≤50 years vs. 14.1% of patients ≥50 years in a 36-month follow-up. Peak VO2 (pVO2), VE/VCO2 slope and percentage of predicted pVO2 were strong independent predictors of outcomes. The International Society for Heart and Lung Transplantation thresholds of pVO2 ≤ 12 mL/kg/min (≤14 if intolerant to ß-blockers), VE/VCO2 slope > 35 and percentage of predicted pVO2 ≤ 50% presented a higher overall diagnostic effectiveness in younger patients (≤50 years). Specific thresholds for each age subgroup outperformed the traditional cut-offs. Conclusions: Personalized age-specific thresholds may contribute to an accurate risk stratification in HFrEF. Further studies are needed to address the gap in evidence between younger and older patients.

Cardiopulmonary Exercise Testing in the Age of New Heart Failure Therapies: Still a Powerful Tool?

BACKGROUND: New therapies with prognostic benefits have been recently introduced in heart failure with reduced ejection fraction (HFrEF) management. The aim of this study was to evaluate the prognostic power of current listing criteria for heart transplantation (HT) in an HFrEF cohort submitted to cardiopulmonary exercise testing (CPET) between 2009 and 2014 (group A) and between 2015 and 2018 (group B). METHODS: Consecutive patients with HFrEF who underwent CPET were followed-up for cardiac death and urgent HT. RESULTS: CPET was performed in 487 patients. The composite endpoint occurred in 19.4% of group A vs. 7.4% of group B in a 36-month follow-up. Peak VO2 (pVO2) and VE/VCO2 slope were the strongest independent predictors of mortality. International Society for Heart and Lung Transplantation (ISHLT) thresholds of pVO2 ≤ 12 mL/kg/min (≤14 if intolerant to ß-blockers) and VE/VCO2 slope > 35 presented a similar and lower Youden index, respectively, in group B compared to group A, and a lower positive predictive value. pVO2 ≤ 10 mL/kg/min and VE/VCO2 slope > 40 outperformed the traditional cut-offs. An ischemic etiology subanalysis showed similar results. CONCLUSION: ISHLT thresholds showed a lower overall prognostic effectiveness in a contemporary HFrEF population. Novel parameters may be needed to improve risk stratification.

Scratch and Wear Behaviour of Co-Cr-Mo Alloy in Ringer's Lactate Solution.

Cobalt-chromium-molybdenum (Co-Cr-Mo) alloy is a material recommended for biomedical implants; however, to be suitable for this application, it should have good tribological properties, which are related to grain size. This paper investigates the tribological behaviour of a Co-Cr-Mo alloy produced using investment casting, together with electromagnetic stirring, to reduce its grain size. The samples were subjected to wear and scratch tests in simulated body fluid (Ringer's lactate solution). Since a reduction in grain size can influence the behaviour of the material, in terms of resistance and tribological response, four samples with different grain sizes were produced for use in our investigation of the behaviour of the alloy, in which we considered the friction coefficient, wear, and scratch resistance. The experiments were performed using a tribometer, with mean values for the friction coefficient, normal load, and tangential force acquired and recorded by the software. Spheres of Ti-6Al-4V and 316L steel were used as counterface materials. In addition, to elucidate the influence of grain size on the mechanical properties of the alloy, observations were conducted via scanning electron microscopy (SEM) with electron backscatter diffraction (EBSD). The results showed changes in the structure, with a reduction in grain size from 5.51 to 0.79 mm. Using both spheres, the best results for the friction coefficient and wear volume corresponded to the sample with the smallest grain size of 0.79 mm. The friction coefficients obtained were 0.37 and 0.45, using the Ti-6Al-4V and 316L spheres, respectively. These results confirm that the best surface finish for Co-Cr-Mo alloy used as a biomedical implant is one with a smaller grain size, since this results in a lower friction coefficient and low wear.

Sacubitril/Valsartan Improves Left Atrial and Ventricular Strain and Strain Rate in Patients with Heart Failure with Reduced Ejection Fraction.

BACKGROUND: Data on the impact of sacubitril/valsartan (SV) therapy on phasic left atrial (LA) and left ventricular (LV) strain in heart failure with reduced ejection fraction (HFrEF) are limited. The aim of this study was to evaluate changes in two-dimensional speckle tracking (2D-STE) parameters with SV therapy in HFrEF patients. METHODS: Prospective evaluation of HFrEF patients receiving optimized medical therapy. Two-dimensional speckle tracking (2D-STE) parameters were assessed at baseline and after 6 months of SV therapy. LA strain and strain rate (SR) in reservoir, conduit, and contraction phases were compared with LV longitudinal, radial, and circumferential strain and SR and stratified according to heart rhythm and HFrEF etiology. RESULTS: A total of 35 patients completed the 6-month follow-up, with a mean age of 59 ± 11 years, 40% in atrial fibrillation, 43% with ischemic etiology, and LVEF of 29 ± 6%. There were significant improvements in LA reservoir, conduit, and contractile strain and SR following SV therapy, particularly among patients in sinus rhythm. There were significant improvements in longitudinal, radial, and circumferential LV function indices. CONCLUSION: SV therapy in HFrEF was associated with improved longitudinal, radial, and circumferential function, particularly among patients in sinus rhythm. These findings can provide insights into the mechanisms underlying the improvement of cardiac function and help assess subclinical responses to the treatment.

Adding Value to Secondary Aluminum Casting Alloys: A Review on Trends and Achievements.

Aluminum is a critical element of the circular economy as it can be recycled several times. Moreover, Al recycling is a more economically and environmentally efficient procedure than the primary Al production from ores. Secondary aluminum alloys are mostly used in casting applications since it is possible to accommodate their chemical composition through secondary manufacturing processes. However, the quality of the alloys may be considerably altered during the different steps of the recycling process. Inadequate waste sorting might result in excessive contamination. Iron is the most dangerous contaminant because it causes brittle and fragile intermetallic phases, which significantly impacts the mechanical characteristics of alloys. In addition, the microstructure of the alloy changes significantly after multiple cycles of remelting. These issues lead to the downcycling of aluminum, i.e., in other words, the reduction in the overall quality of the alloys. Thus, it has been shown that a number of procedures, including ultrasonic melt treatment and microalloying with rare earths, can somewhat alter the shape of the Fe-rich phases in order to reduce the shortcomings of downcycling. However, a solid mechanical characterization is still missing in order to improve the Fe-rich phase alteration.

Pediatric androgenetic alopecia: an updated review.

Pediatric androgenetic alopecia is an underrecognized disorder. A clinical evaluation with trichoscopy should be made in children and adolescents with hair loss and/or reduced hair density. Diagnosis is usually clinical, by observation of the hair loss pattern and performance of trichoscopy. In some cases, hyperandrogenism should be excluded. Although there is no approved therapy for androgenetic alopecia in pediatric age, topical minoxidil, oral minoxidil and topical finasteride may be very useful. Hair transplant may be an option for girls in selected cases. This article is a review of the current state of evidence concerning pediatric androgenetic alopecia.

When Do We Perform Elective Total Knee Arthroplasty? General and Demographic-Specific Trends of Preoperative Pain and Function among 10,327 Patients.

Total knee arthroplasty (TKA) is the sole disease-modifying intervention for end-stage osteoarthritis. However, the temporal trends and stratification of age and patient demographics of pain and function levels at which surgeons perform TKA have not been characterized. The present investigation aimed to analyze the temporal trends of preoperative pain and functional patient-reported outcomes measures (PROMs) over the past 5 years when stratifying patient demographics. A prospective cohort of all patients who underwent primary elective TKA between January 2016 and December 2020 at a North American integrated tertiary health care system was retrospectively reviewed. The primary outcome was quarterly baseline (preoperative) pain and function PROM values before primary elective TKA. Evaluated PROMs included Knee Osteoarthritis Outcome Score (KOOS)-pain and KOOS-physical function shortform (PS) for the 5-year study period and were stratified by patient demographics (age, sex, race, and body mass index [BMI]). A total of 10,327 patients were analyzed. Preoperative pain levels remained unchanged over the study period for patients in the 45- to 64-year category (P-trend = 0.922). Conversely, there was a significant improvement in preoperative pain levels in the 65+ years group. Sex-stratified trends between males and females did not demonstrate a significant change in pre-TKA baseline pain over the study period (P-trend = 0.347 and P-trend = 0.0744). Both white and black patients demonstrated consistent KOOS-pain levels throughout the study period (P-trend = 0.0855 and P-trend = 0.626). Only white patients demonstrated improving preoperative KOOS-PS (P-trend = 0.0001), while black and "other" patients demonstrated consistent lower preoperative functional levels throughout the study period (P-trend = 0.456 and P-trend = 0.871). All BMI categories demonstrated relatively consistent preoperative KOOS-pain and KOOS-PS except for overweight and obese patients who demonstrated progressive improvement in preoperative KOOS-PS over the study period. Patients and surgeons are electing to perform primary TKA at higher levels of preoperative function. Stratification by race showed black patients did not experience a similar trend of improving function and exhibited a consistently lower functional level versus white patients. This disparity is likely to be multifactorial but may indicate underlying barriers to TKA access.

Absence of Synergism between a Dual-AMP Biogel and Antibiotics Used as Therapeutic Agents for Diabetic Foot Infections.

Diabetic foot infections (DFIs) are frequently linked to diabetic-related morbidity and death because of the ineffectiveness of conventional antibiotics against multidrug-resistant bacteria. Pexiganan and nisin A are antimicrobial peptides (AMPs), and their application may complement conventional antibiotics in DFI treatment. A collagen 3D model, previously established to mimic a soft-tissue collagen matrix, was used to evaluate the antibacterial efficacy of a guar gum gel containing pexiganan and nisin alone and combined with three antimicrobials toward the biofilms of Staphylococcus aureus and Pseudomonas aeruginosa isolated from infected foot ulcers. Antimicrobials and bacterial diffusion were confirmed by spot-on-lawn and bacterial growth by bacterial count (cfu/mL). Our main conclusion was that the dual-AMP biogel combined with gentamicin, clindamycin, or vancomycin was not able to significantly reduce bacterial growth or eradicate S. aureus and P. aeruginosa DFI isolates. We further reported an antagonism between dual-AMP and dual-AMP combined with antibiotics against S. aureus.

SARS-CoV-2 air and surface contamination in residential settings.

SARS-CoV-2 transmission occurs mainly indoors, through virus-laden airborne particles. Although the presence and infectivity of SARS-CoV-2 in aerosol are now acknowledged, the underlying circumstances for its occurrence are still under investigation. The contamination of domiciliary environments during the isolation of SARS-CoV-2-infected patients in their respective rooms in individual houses and in a nursing home was investigated by collecting surface and air samples in these environments. Surface contamination was detected in different contexts, both on high and low-touch surfaces. To determine the presence of virus particles in the air, two sampling methodologies were used: air and deposition sampling. Positive deposition samples were found in sampling locations above the patient's height, and SARS-CoV-2 RNA was detected in impactation air samples within a size fraction below 2.5 µm. Surface samples rendered the highest positivity rate and persistence for a longer period. The presence of aerosolized SARS-CoV-2 RNA occurred mainly in deposition samples and closer to symptom onset. To evaluate the infectivity of selected positive samples, SARS-CoV-2 viability assays were performed, but our study was not able to validate the virus viability. The presented results confirm the presence of aerosolized SARS-CoV-2 RNA in indoor compartments occupied by COVID-19 patients with mild symptoms, in the absence of aerosol-generating clinical procedures.

The prognostic value of the cardiorespiratory optimal point during submaximal exercise testing in heart failure.

INTRODUCTION: Peak oxygen consumption (pVO2) is a key parameter for assessing the prognosis of heart failure with reduced ejection fraction (HFrEF). However, it is less reliable when the cardiopulmonary exercise test (CPET) is not maximal. OBJECTIVE: To compare the prognostic power of various exercise parameters in submaximal CPET. METHODS: Adult patients with HFrEF undergoing CPET in a tertiary center were prospectively assessed. Submaximal CPET was defined as a respiratory exchange ratio ≤1.10. Patients were followed for one year for the primary endpoint of cardiac death and urgent heart transplantation (HT). Various CPET parameters were analyzed as potential predictors of the combined endpoint and their prognostic power (area under the curve [AUC]) was compared using the Hanley-McNeil test. RESULTS: CPET was performed in 442 HFrEF patients (mean age 56±12 years, 80% male), of whom 290 (66%) had a submaximal CPET. Seventeen patients (6%) reached the primary endpoint. The cardiorespiratory optimal point (COP) had the highest AUC value (0.989, p<0.001), and significantly higher prognostic power than other tested parameters, with pVO2 presenting an AUC of 0.753 (p=0.001). COP ≥36 had significantly lower survival free of HT during follow-up (p<0.001) and presented a sensitivity of 100% and a specificity of 89% for the primary endpoint. CONCLUSION: COP had the highest prognostic power of all parameters analyzed in a submaximal CPET. This parameter can help stratify HFrEF patients who are physiologically unable to reach a maximal level of exercise.

Capacidade Preditiva dos Parâmetros do Teste de Esforço Cardiopulmonar em Pacientes com Insuficiência Cardíaca em Terapia de Ressincronização Cardíaca / Predictive Ability of Cardiopulmonary Exercise Test Parameters in Heart Failure Patients with Cardiac Resynchronization Therapy

Resumo Fundamento Há evidências sugerindo que um corte do pico de consumo de oxigênio (pVO2) de 10ml/kg/min fornece uma estratificação de risco mais precisa em pacientes com Terapia de Ressincronização Cardíaca (TRC). Objetivo Comparar o poder prognóstico de vários parâmetros do teste cardiopulmonar de exercício (TCPE) nesta população e avaliar a capacidade discriminativa dos valores de corte de pVO2 recomendados pelas diretrizes. Métodos Avaliação prospectiva de uma série consecutiva de pacientes com insuficiência cardíaca (IC) com fração de ejeção do ventrículo esquerdo ≤40%. O desfecho primário foi um composto de morte cardíaca e transplante cardíaco urgente (TC) nos primeiros 24 meses de acompanhamento, e foi analisado por vários parâmetros do TCPE para a maior área sob a curva (AUC) no grupo TRC. Uma análise de sobrevida foi realizada para avaliar a estratificação de risco fornecida por vários pontos de corte diferentes. Valores de p < 0,05 foram considerados significativos. Resultados Um total de 450 pacientes com IC, dos quais 114 possuíam aparelho de TRC. Esses pacientes apresentaram um perfil de risco basal mais alto, mas não houve diferença em relação ao desfecho primário (13,2% vs 11,6%, p = 0,660). A pressão expiratória de dióxido de carbono no limiar anaeróbico (PETCO2AT) teve o maior valor de AUC, que foi significativamente maior do que o de pVO2 no grupo TRC (0,951 vs 0,778, p = 0,046). O valor de corte de pVO2 atualmente recomendado forneceu uma estratificação de risco precisa nesse cenário (p <0,001), e o valor de corte sugerido de 10 ml/min/kg não melhorou a discriminação de risco em pacientes com dispositivos (p = 0,772). Conclusão A PETCO2AT pode superar o poder prognóstico do pVO2 para eventos adversos em pacientes com TRC. O ponto de corte de pVO2 recomendado pelas diretrizes atuais pode estratificar precisamente o risco dessa população.

Abstract Background There is evidence suggesting that a peak oxygen uptake (pVO2) cut-off of 10ml/kg/min provides a more precise risk stratification in cardiac resynchronization therapy (CRT) patients. Objective To compare the prognostic power of several cardiopulmonary exercise testing (CPET) parameters in this population and assess the discriminative ability of the guideline-recommended pVO2cut-off values. Methods Prospective evaluation of consecutive heart failure (HF) patients with left ventricular ejection fraction ≤40%. The primary endpoint was a composite of cardiac death and urgent heart transplantation (HT) in the first 24 follow-up months, and was analysed by several CPET parameters for the highest area under the curve (AUC) in the CRT group. A survival analysis was performed to evaluate the risk stratification provided by several different cut-offs. p values <0.05 were considered significant. Results A total of 450 HF patients, of which 114 had a CRT device. These patients had a higher baseline risk profile, but there was no difference regarding the primary outcome (13.2% vs 11.6%, p =0.660). End-tidal carbon dioxide pressure at anaerobic threshold (PETCO2AT)had the highest AUC value, which was significantly higher than that of pVO2in the CRT group (0.951 vs 0.778, p =0.046). The currently recommended pVO2cut-off provided accurate risk stratification in this setting (p <0.001), and the suggested cut-off value of 10 ml/min/kg did not improve risk discrimination in device patients (p =0.772). Conclusion PETCO2ATmay outperform pVO2's prognostic power for adverse events in CRT patients. The current guideline-recommended pVO2 cut-off can precisely risk-stratify this population.