The c.415C>T polymorphism in NUDT15 is more frequent than the polymorphisms in TPMT in Chilean patients who use thiopurine drugs.

Azathioprine (AZA) and 6-mercaptopurine (6-MP) are drugs widely used in the treatment of autoimmune diseases. Among the enzymes involved in the metabolism of AZA and 6-MP are thiopurine methyltransferase (TPMT) and nudix hydrolase 15 (NUDT15). The existence of single nucleotide polymorphisms in the genes that code for these enzymes could decreased enzymatic activity AND lead to severe myelosuppression. The most relevant polymorphism is NUDT15*3 (rs116855232), where the replacement of cytosine for thymine at position 415, which in turn leads to a loss of enzymatic activity. In a previous study, it was identified that together the polymorphisms in the TPMT gene reach an allelic frequency of 3.81%. There is no information regarding the rs116855232 polymorphism in the NUDT15 gene, so this corresponds to the objective of this report. Blood samples from Chilean adult patients with indications for the use of AZA or 6-MP for different pathologies and who had undergone a TPMT gene polymorphism study were retrospectively analyzed. A total of 253 blood samples were analyzed. Of the 253 patients, 47 presented the c.415C>T polymorphism in the NUDT15 gene, 3 being homozygous and 44 heterozygous. Four of the heterozygous patients for NUDT15 also had the *3A variant in the TPMT gene, also heterozygous. The allelic frequency of the minor T allele found (9.88%) was very similar to that found in patients of Asian origin, and much higher than that reported for the European Caucasian or Latin American population.

Home Based Rehabilitation in Children and Adolescents with Cystic Fibrosis: A Systematic Review with Meta-Analysis and Grade Recommendations.

OBJECTIVE: The objective of this study is to elucidate the effectiveness of home based rehabilitation (HBR) and compare its results with those obtained in conventional rehabilitation (CR) programs, carried out in clinics and/or outpatient clinics. METHODS: Searches were conducted in five databases of randomized clinical trials. Study selection, data extraction, and assessment of the methodological quality of included studies were conducted independently by two reviewers, with discrepancies resolved by a third reviewer. RESULTS: The results demonstrate post-intervention values favorable to the use of HBR when compared to control group in the outcomes of forced expiratory volume in 1 second (FEV1) (MD = 14% CI: 5.42 to 22.58, p = 0.001), forced vital capacity (FVC) (MD = 8.00% CI: 0.83 to 15.17, p = 0.03) and quality of life by the Cystic Fibrosis Questionnaire - revised in the categories (Child version score" (MD= 0.71%CI: 0.15 to 1.27, p = 0.01) and "Parent version score" (MD= 0.67%CI: 0.11 to 1.23, p = 0.02). Furthermore, we noticed an increase in the distance covered in the 6-minute walk test (MD= 34.75%CI: -8.00 to 77.50, p = 0.14), in favor of HBR. CONCLUSIONS: We found that supervised or partially supervised HBR promotes improvements in FEV1, FVC and related quality of life in children and/or adolescents with cystic fibrosis.

Host-pathogen interaction between macrophage co-cultures with Staphylococcus aureus biofilms.

The ability of Staphylococcus aureus to form biofilms is an important virulence factor. During the infectious process, the interaction between biofilms and immune cells is determinant; however, the properties that make biofilms resistant to the immune system are not well characterized. In order to better understand this, we evaluated the in vitro interaction of macrophages during the early stages of S. aureus biofilm formation. Biofilm formation was evaluated by crystal violet staining, light microscopy, and confocal scanning laser microscopy. Furthermore, different activation on L-arginine pathways such as nitric oxide (NO•) release and the arginase, the production of reactive oxygen species (ROS), the total oxidative stress response (OSR), and levels of cytokine liberation, were determined. Our findings show that the interaction between biofilms and macrophages results in stimuli for catabolism of L-arginine via arginase, but not for NO•, an increase of ROS production, and activation of the non-enzymatic OSR. We also observed the production of IL-6, but not of TNFα o IL-10 in these co-cultures. These results contribute to a better understanding of host-pathogen interactions and suggest that biofilms increase resistance against immune cell mechanisms, a phenomenon that could contribute to the ability of S. aureus biofilms to establish mature biofilms.

Liver transplantation in acute liver failure due to Hepatitis B. Two clinical cases.

Hepatitis B virus (HBV) related acute liver failure (ALF) is uncommon in our region, and there is limited HBV literature regarding the optimal management of these cases. In this article, we report two clinical cases of young men who have sex with men (MSM), both developed severe acute hepatitis caused by HBV, progressed to ALF and afterward required liver transplantation. Antiviral post-transplant treatment included entecavir without Hepatitis B Immunoglobulin (HBIG), and immunosuppression therapy with steroids, tacrolimus, and mycophenolate. Serologic follow-up showed early Hepatitis B surface Antigen (HBsAg) seroconversion, undetectable HBV viral load, and positive Anti-HBs titers. During later follow-up, Anti-HBs titers gradually fell (<10mUI/L after six months), with normal liver function. DISCUSSION: In cases of HBV-related ALF, the liver develops a robust immune response, leading to, an early undetectable viral load and seroconversion, with loss of HBsAg, and the appearance of Anti-HBs as a result of the inflammatory response. The management varies depending on whether this is a de novo acute infection or a reactivation of a previous chronic infection. In both cases, the use of antiviral therapy is recommended, with entecavir or tenofovir, among others, but the use of specific HBIG is supported only in ALF related to chronic HBV infection. The optimal length of the antiviral therapy after liver transplantation is still under discussion. CONCLUSION: These cases of HBV related ALF with an early HBsAg seroconversion demonstrates the relevance of requesting IgM antibody against hepatitis B core antigen (anti-HBc IgM) for the etiological study of ALF with negative HBsAg. Usage of HBIG does not seem essential during the post-transplantation period in these cases.

Oxidative and nitrosative stress responses during macrophage-Candida albicans biofilm interaction.

Candida albicans is an important source of device-associated infection because of its capacity for biofilm formation. This yeast has the ability to form biofilms which favors the persistence of the infection. Furthermore, the innate immune response has a critical role in the control of these infections and macrophages (Mø) are vital to this process. An important fungicidal mechanism employed by Mø involves the generation of toxic reactive oxygen species (ROS) and reactive nitrogen intermediates (RNI). The interaction between biofilms and these immune cells, and the contribution of oxidative and nitrosative stress, that is determinant to the course of the infection, remains elusive. The aim of this study was to investigate this interaction. To this purpose, two models of Mø-biofilms contact, early (model 1) and mature (model 2) biofilms, were used; and the production of ROS, RNI and the oxidative stress response (OSR) were evaluated. We found that the presence of Mø decreased the biofilm formation at an early stage and increased the production of ROS and RNI, with activation of ORS (enzymatic and nonenzymatic). On the other hand, the interaction between mature biofilms and Mø resulted in an increasing biofilm formation, with low levels of RNI and ROS production and decrease of OSR. Dynamic interactions between Mø and fungal biofilms were also clearly evident from images obtained by confocal scanning laser microscopy. The prooxidant-antioxidant balance was different depending of C. albicans biofilms stages and likely acts as a signal over their formation in presence of Mø. These results may contribute to a better understanding of the immune-pathogenesis of C. albicans biofilm infections.

Transient acute kidney injury after cardiac surgery does not independently affect postoperative outcomes.

BACKGROUND: The objective of this study was to assess the incidence of in-hospital acute kidney injury (AKI) after cardiac surgery by comparing preoperative baseline renal function with renal function during the postoperative period and at discharge, and to relate these indices with in-hospital postoperative outcomes. METHODS: A retrospective analysis was performed over a 4-year period from a series of 426 adult patients. Kidney function was based on serum creatinine (SCr), Cockroft-Gault estimated creatinine clearance (eCrCl), and glomerular filtration rate estimated with the Modification of Diet in Renal Disease formula (eGFR). Baseline values were compared with "peak" values of altered kidney function postoperatively, and "discharge" values. In-hospital mortality and complication rates were compared between patients with transient and persistent AKI, and those without postoperative AKI. RESULTS: After surgery, AKI (Risk-Injury-Failure-Loss-Endstage [RIFLE] classes Injury and Failure) was diagnosed in 14.6-17.5% of patients based on peak values. AKI diagnosis was reduced to 3.6-4.5% when SCr, eCrCl, and eGFR were measured at discharge. In-hospital mortality of patients with transient AKI was 4% versus 26% in patients with AKI at discharge (odds ratio = 0.11, 95% confidence interval 0.02-0.62, P = 0.011). CONCLUSIONS: A diagnosis of AKI based on measurements of eGFR during the postoperative period was nearly four times more frequent than the same diagnosis at discharge. Transient AKI was the predominate presentation of postoperative kidney dysfunction in this study. Transient AKI did not affect in-hospital outcomes compared with patients without AKI. Patients with persistent AKI at discharge had the highest mortality.

Association of body mass index with short-term outcomes after cardiac surgery: retrospective study and meta-analysis.

The relationship between higher body mass index (BMI), decreased morbidity and mortality is known as the "obesity paradox", and has been described in cohorts of patients with hypertension, diabetes, heart failure, coronary and peripheral artery diseases, non-cardiac surgery, and end-stage renal disease. Here we investigated the relationship between BMI and short-term outcomes after adult cardiac surgery to explore the existence of an obesity paradoxical effect. A secondary objective was to perform an updated systematic review to further analyze the association between BMI and 30-day in-hospital mortality after cardiac surgery. A retrospective analysis was performed from a consecutive series of 1823 adult patients who underwent cardiac surgery, that were assigned to five BMI groups: normal weight (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), class I obese (30-34.9 kg/m2), class II obese (35-39.9 kg/m2), and class III obese or morbidly obese (40-49.9 kg/m2). A systematic review search was performed including controlled trials and observational studies identified in MEDLINE, Embase, SCOPUS, and the Cochrane library (to the end of June 2017). In the present series, overweight and obese patients had similar or slightly lower in-hospital mortality rates after cardiac surgery compared with normal-weight individuals. Conversely, postoperative complication rates increased with higher BMI levels. Most studies included in the review showed that overweight and obese patients had at least the same mortality rate as normal-weight patients, or even a lower death risk. Pooled-data of the meta-analysis provided evidence on the association between higher BMI levels and a lower all-cause in-hospital mortality rate after cardiac surgery.

Critical Uncertainties and Gaps in the Environmental- and Social-Impact Assessment of the Proposed Interoceanic Canal through Nicaragua.

The proposed interoceanic canal will connect the Caribbean Sea with the Pacific Ocean, traversing Lake Nicaragua, the major freshwater reservoir in Central America. If completed, the canal would be the largest infrastructure-related excavation project on Earth. In November 2015, the Nicaraguan government approved an environmental and social impact assessment (ESIA) for the canal. A group of international experts participated in a workshop organized by the Academy of Sciences of Nicaragua to review this ESIA. The group concluded that the ESIA does not meet international standards; essential information is lacking regarding the potential impacts on the lake, freshwater and marine environments, and biodiversity. The ESIA presents an inadequate assessment of natural hazards and socioeconomic disruptions. The panel recommends that work on the canal project be suspended until an appropriate ESIA is completed. The project should be resumed only if it is demonstrated to be economically feasible, environmentally acceptable, and socially beneficial.

Scientists raise alarms about fast tracking of transoceanic canal through Nicaragua.

Seeking economic growth and job creation to tackle the nation's extreme poverty, the Nicaraguan government awarded a concession to build an interoceanic canal and associated projects to a recently formed Hong Kong based company with no track record or related expertise. This concession was awarded without a bidding process and in advance of any feasibility, socio-economic or environmental impact assessments; construction has begun without this information. The 278 km long interoceanic canal project may result in significant environmental and social impairments. Of particular concern are damage to Lake Cocibolca, a unique freshwater tropical lake and Central America's main freshwater reservoir; damage to regional biodiversity and ecosystems; and socio-economic impacts. Concerned about the possibly irreparable damage to the environment and to native communities, conservationists and the scientific community at large are urging the Nicaraguan government to devise and reveal an action plan to address and mitigate the possible negative repercussions of this interoceanic canal and associated projects. Critical research needs for preparation of a comprehensive benefit-cost analysis for this megaproject are presented.

Complete proteome of a quinolone-resistant Salmonella Typhimurium phage type DT104B clinical strain.

Salmonellosis is one of the most common and widely distributed foodborne diseases. The emergence of Salmonella strains that are resistant to a variety of antimicrobials is a serious global public health concern. Salmonella enterica serovar Typhimurium definitive phage type 104 (DT104) is one of these emerging epidemic multidrug resistant strains. Here we collate information from the diverse and comprehensive range of experiments on Salmonella proteomes that have been published. We then present a new study of the proteome of the quinolone-resistant Se20 strain (phage type DT104B), recovered after ciprofloxacin treatment and compared it to the proteome of reference strain SL1344. A total of 186 and 219 protein spots were recovered from Se20 and SL1344 protein extracts, respectively, after two-dimensional gel electrophoresis. The signatures of 94% of the protein spots were successfully identified through matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS). Three antimicrobial resistance related proteins, whose genes were previously detected by polymerase chain reaction (PCR), were identified in the clinical strain. The presence of these proteins, dihydropteroate synthase type-2 (sul2 gene), aminoglycoside resistance protein A (strA gene) and aminoglycoside 6'-N-acetyltransferase type Ib-cr4 (aac(6')-Ib-cr4 gene), was confirmed in the DT104B clinical strain. The aac(6')-Ib-cr4 gene is responsible for plasmid-mediated aminoglycoside and quinolone resistance. This is a preliminary analysis of the proteome of these two S. Typhimurium strains and further work is being developed to better understand how antimicrobial resistance is developing in this pathogen.

[Procalcitonin and C-reactive protein as early indicators of postoperative intra-abdominal infection after surgery for gastrointestinal cancer]. / Procalcitonina y proteína C reactiva como marcadores precoces de infección intraabdominal postoperatoria en pacientes operados de cáncer gastrointestinal.

AIM: to evaluate the association between serum levels of procalcitonin and C-reactive protein, on the first 3 postoperative days, and the appearance of postoperative intra-abdominal infection. METHOD: Prospective observational study including 67 patients operated on for colo-rectal, gastric and pancreatic cancer. Serum levels of procalcitonin and C-reactive protein were analyzed before surgery and daily until the third postoperative day. Values of procalcitonin (PCT) and C-reactive protein (CRP) were recorded as well as their accuracy for detection of postoperative intra-abdominal infection (PIAI). RESULTS: The incidence of postoperative intra-abdominal infection was 13.4%. CRP serum levels at 72h, PCT serum levels at 24, 48 and 72h and the ratio between serum levels of CRP at 72hours and serum levels of CRP at 48hours (CRP D3/CRP D2) were significantly associated with the appearance of postoperative intra-abdominal infection. The highest sensitivity corresponded to PCT at 72hours (88.9%); the highest specificity and positive predictive value corresponded to the ratio CRP D3/CRP D2 (96.49% and 71.4%, respectively); the highest negative predictive value to procalcitonin at 72h and 24h. CONCLUSIONS: Serum levels of PCT are significantly associated with the appearance of postoperative intra-abdominal infection. Sensitivity and predictive positive values are low, but negative predictive value is high, even at 24h after surgery.

Recent Trends in Curcumin-Containing Inorganic-Based Nanoparticles Intended for In Vivo Cancer Therapy.

Curcumin is a natural compound that has been widely investigated thanks to its various biological properties, including antiproliferative. This molecule acts on different cancers such as lung, breast, pancreatic, colorectal, etc. However, the bioactive actions of curcumin have limitations when its physicochemical properties compromise its pharmacological potential. As a therapeutic strategy against cancer, curcumin has been associated with inorganic nanoparticles. These nanocarriers are capable of delivering curcumin and offering physicochemical properties that synergistically enhance anticancer properties. This review highlights the different types of curcumin-based inorganic nanoparticles and discusses their physicochemical properties and in vivo anticancer activity in different models of cancer.

Beyond Traditional Sunscreens: A Review of Liposomal-Based Systems for Photoprotection.

Sunscreen products are essential for shielding the skin from ultraviolet (UV) radiation, a leading cause of skin cancer. While existing products serve this purpose, there is a growing need to enhance their efficacy while minimizing potential systemic absorption of UV filters and associated toxicological risks. Liposomal-based formulations have emerged as a promising approach to address these challenges and develop advanced photoprotective products. These vesicular systems offer versatility in carrying both hydrophilic and lipophilic UV filters, enabling the creation of broad-spectrum sunscreens. Moreover, their composition based on phospholipids, resembling that of the stratum corneum, facilitates adherence to the skin's surface layers, thereby improving photoprotective efficacy. The research discussed in this review underscores the significant advantages of liposomes in photoprotection, including their ability to limit the systemic absorption of UV filters, enhance formulation stability, and augment photoprotective effects. However, despite these benefits, there remains a notable gap between the potential of liposomal systems and their utilization in sunscreen development. Consequently, this review emphasizes the importance of leveraging liposomes and related vesicular systems as innovative tools for crafting novel and more efficient photoprotective formulations.

One hundred years of grain omics: identifying the glutens that feed the world.

Glutens, the storage proteins in wheat grains, are a major source of protein in human nutrition. The protein composition of wheat has therefore been an important focus of cereal research. Proteomic tools have been used to describe the genetic diversity of wheat germplasms from different origins at the level of polymorphisms in alleles encoding glutenin and gliadin, the two main proteins of gluten. More recently, proteomics has been used to understand the impact of specific gluten proteins on wheat quality. Here we review the impact of proteomics on the study of gluten proteins as it has evolved from fractionation and electrophoretic techniques to advanced mass spectrometry. In the postgenome era, proteomics is proving to be essential in the effort to identify and understand the interactions between different gluten proteins. This is helping to fill in gaps in our knowledge of how the technological quality of wheat is determined by the interaction between genotype and environment. We also collate information on the various storage protein alleles identified and their prevalence, which makes it possible to infer the effects of wheat selection on grain protein content. We conclude by reviewing the more recent use of transgenesis aimed at improving the quality of gluten.

The Efficacy of Manual Therapy Approaches on Pain, Maximum Mouth Opening and Disability in Temporomandibular Disorders: A Systematic Review of Randomised Controlled Trials.

Temporomandibular disorder (TMD) is a common condition disabling people and bringing up costs. The aim of this study was to investigate the effects of manual therapy on pain intensity, maximum mouth opening (MMO) and disability. Searches were conducted in six databases for randomised controlled trials (RCTs). Selection of trials, data extraction and methodological quality assessment were conducted by two reviewers with discrepancies resolved by a third reviewer. Estimates were presented as mean differences (MDs) or standardized mean differences (SMDs) with 95% confidence intervals (CIs). Quality of the evidence was assessed using the GRADE approach. Twenty trials met the eligibility criteria and were included. For pain intensity, high and moderate quality evidence demonstrated the additional effects of manual therapy at short- (95% CI -2.12 to -0.82 points) and long-term (95% CI -2.17 to -0.40 points) on the 0-10 points scale. For MMO, moderate to high quality evidence was found in favour of manual therapy alone (95% CI 0.01 to 7.30 mm) and its additional effects (95% CI 1.58 to 3.58 mm) at short- and long-term (95% CI 1.22 to 8.40 mm). Moderate quality evidence demonstrated an additional effect of manual therapy for disability (95% CI = -0.87 to -0.14). Evidence supports manual therapy as effective for TMD.

Insights into SARS-CoV-2 in Angola during the COVID-19 peak: Molecular epidemiology and genome surveillance.

Background: In Angola, COVID-19 cases have been reported in all provinces, resulting in >105,000 cases and >1900 deaths. However, no detailed genomic surveillance into the introduction and spread of the SARS-CoV-2 virus has been conducted in Angola. We aimed to investigate the emergence and epidemic progression during the peak of the COVID-19 pandemic in Angola. Methods: We generated 1210 whole-genome SARS-CoV-2 sequences, contributing West African data to the global context, that were phylogenetically compared against global strains. Virus movement events were inferred using ancestral state reconstruction. Results: The epidemic in Angola was marked by four distinct waves of infection, dominated by 12 virus lineages, including VOCs, VOIs, and the VUM C.16, which was unique to South-Western Africa and circulated for an extended period within the region. Virus exchanges occurred between Angola and its neighboring countries, and strong links with Brazil and Portugal reflected the historical and cultural ties shared between these countries. The first case likely originated from southern Africa. Conclusion: A lack of a robust genome surveillance network and strong dependence on out-of-country sequencing limit real-time data generation to achieve timely disease outbreak responses, which remains of the utmost importance to mitigate future disease outbreaks in Angola.

[Prognostic factors for malnutrition in patients with colorectal cancer]. / Factores pronósticos de desnutrición en pacientes con cáncer colorrectal.

Introduction: Introduction: patients undergoing major abdominal surgery, including colorectal surgery, particularly if they are oncological patients, are at risk of malnutrition with a worse postoperative evolution and an increase in complications. Objectives: to assess the prevalence of malnutrition in patients undergoing colon and rectal surgery in our hospital, and to identify the different risk factors for malnutrition. Methods: a retrospective cohort study including all patients operated on for colorectal cancer in our environment. Results: a total of 382 patients with a mean age of 69.93 years were included in the study. Considering different risk factors for malnutrition, we obtained that 50.6 % of the patients had some of the risk indicators for malnutrition altered at the time of admission. The variables that proved to be independent factors related to malnutrition were age, DM, baseline malnutrition, and heart disease. Preoperative malnutrition turned out to be the greatest risk factor for presenting moderate/severe malnutrition in the postoperative period with an OR of 3.83 (2.1-6.9; p < 0.001), and was also associated with a higher incidence of postoperative complications and longer hospital stays. We obtained that the percentage of postoperative complications was significantly higher in the group of patients diagnosed with peroperative malnutrition (36.3 % vs 22.0 %, p = 0.004). Conclusions: the percentage of malnutrition in patients with colorectal cancer is high, an aspect that is underestimated in most surgical services. In our study, malnutrition leads to worse outcomes with an increase in complications.

Introducción: Introducción: los pacientes sometidos a cirugía mayor abdominal, y más si se trata de pacientes oncológicos, son pacientes en riesgo de desnutrición, lo que conlleva una peor evolución posoperatoria y un aumento de las complicaciones. Objetivos: conocer la prevalencia de la desnutrición en los pacientes sometidos a cirugía de colon y recto en nuestro medio hospitalario e identificar los distintos factores de riesgo de desnutrición. Métodos: estudio de cohortes retrospectivo incluyendo a todos los pacientes intervenidos de cáncer colorrectal de forma programada en nuestro medio hospitalario. Resultados: se incluyeron en el estudio 382 pacientes con una edad media de 69,93 años. Considerando distintos factores de riesgo de desnutrición, obtuvimos que un 50,6 % de los pacientes tenían alterado alguno de los indicadores de riesgo de desnutrición en el momento del ingreso. Las variables que mostraron ser factores independientes relacionados con la desnutrición fueron la edad, la DM, la desnutrición basal y la cardiopatía. La desnutrición preoperatoria resultó ser el factor de mayor riesgo para presentar desnutrición moderada/grave en el posoperatorio con un OR de 3,83 (2,1-6,9; p < 0,001) y además se asoció a una mayor incidencia de complicaciones posoperatorias y a estancias hospitalarias más prolongadas. Obtuvimos que el porcentaje de complicaciones posoperatorias fue significativamente mayor en el grupo de pacientes diagnosticados de desnutrición peroperatoria (36,3 % vs. 22,0 %, p = 0,004). Conclusiones: el porcentaje de desnutrición en los pacientes con cáncer colorrectal es elevado, aspecto subestimado en la mayoría de los servicios quirúrgicos. La desnutrición conlleva en nuestro estudio una peor evolución con un incremento de las complicaciones.

The ESCAPE trial for older people with chronic low back pain: Protocol of a randomized controlled trial.

BACKGROUND: Low-back pain is one of the most common health conditions worldwide. It is defined as pain below the costal margin and above the inferior gluteal folds. Current guidelines recommend management of chronic health (e.g., low back pain) conditions in older people at primary health care settings using active strategies (e.g., exercise). In non-specific low back pain, high quality evidence supports active strategies for general population. However, the management of non-specific low back pain in the older people has been overlooked and evidence is limited to a small number of low powered randomized controlled trials with high risk of bias. METHODS: This is a prospectively registered, open, two-arm randomised controlled trial comparing the group-based exercise and waiting list in pain intensity (11-item Pain Numerical Rating Scale) and disability (Roland Morris questionnaire) of older people (i.e., 60 years old or over) with chronic non-specific low back pain. One hundred and twenty patients will be recruited from Diamantina, Brazil. Follow-ups will be conducted in post-treatment (8 week) and 6- and 12-months post-randomisation. DISCUSSION: Our hypothesis is that group-based exercise will be better than waiting list in reducing pain intensity and disability in older people with chronic non-specific low back pain. IMPACT: The practice of individualized exercise has been studied for the management of chronic non-specific low back pain in older people. However, the group exercise, even showing high quality evidence for the improvement of several important outcomes in this population, has been ignored until now. Thus, the results of this study have the potential to indicate a viable and accessible strategy for managing chronic non-specific low back pain in the older people. TRIAL REGISTRATION: The study was prospectively registered at www.ensaiosclinicos.gov.br (RBR-9j5pqs). Date-11/18/2020.