Melipona stingless bees and honey microbiota reveal the diversity, composition, and modes of symbionts transmission.

The Melipona gut microbiota differs from other social bees, being characterized by the absence of crucial corbiculate core gut symbionts and a high occurrence of environmental strains. We studied the microbial diversity and composition of three Melipona species and their honey to understand which strains are obtained by horizontal transmission (HT) from the pollination environment, represent symbionts with HT from the hive/food stores or social transmission (ST) between nestmates. Bees harbored higher microbial alpha diversity and a different and more species-specific bacterial composition than honey. The fungal communities of bee and honey samples are also different but less dissimilar. As expected, the eusocial corbiculate core symbionts Snodgrassella and Gilliamella were absent in bees that had a prevalence of Lactobacillaceae - including Lactobacillus (formerly known as Firm-5), Bifidobacteriaceae, Acetobacteraceae, and Streptococcaceae - mainly strains close to Floricoccus, a putative novel symbiont acquired from flowers. They might have co-evolved with these bees via ST, and along with environmental Lactobacillaceae and Pectinatus (Veillonellaceae) strains obtained by HT, and Metschnikowia and Saccharomycetales yeasts acquired by HT from honey or the pollination environment, including plants/flowers, possibly compose the Melipona core microbiota. This work contributes to the understanding of Melipona symbionts and their modes of transmission.

Intestinal microbial diversity of swines fed with different sources of lithium.

A drug that is widely used in the treatment of psychiatric disorder is lithium (Li) salts. The people who make therapeutic use of this drug develop a series of side effects. Through metataxonomic data, this study assessed the impacts of lithium, as Li carbonate or Li-enriched mushrooms, on the microbial composition of the ileum, colon, and feces of piglets. Employing Bray-Curtis metric, no differences were observed among the treatments evaluated. Nevertheless, the alpha diversity indices showed differences in the Simpson, Shannon, and Chao-1 indices in the colon and Chao-1 in the feces in the diets with Li compared with the diets without Li. The taxa with the highest relative abundance varied among the ileum, colon, and feces, with a predominance of the phyla Firmicutes, Bacteroidota, and Proteobacteria in diets with Li. Many groups of microorganisms that are important for the health of the host (e.g., Lactobacillus, Ruminococcaceae, Enterorhabdus, Muribaculaceae, and Coprococcus) had their relative abundance increased in animals that received diets with the recommended dose of lithium. Furthermore, there was an increase in the abundance of Prevotellaceae and Bacteroidales (in the diet with Li-enriched mushroom) and Clostridia, Ruminococcus, Burkholderia, and Bacteroidales (diets with Li carbonate) at the recommended dosages. This is the first study to show the effects of Li carbonate and Li-enriched mushrooms on the intestinal microbiota of piglets. Thus, the effects of lithium on the body may be related to its ability to change the composition of the intestinal microbiota. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-03938-3.

Machine learning-based soil quality assessment for enhancing environmental monitoring in iron ore mining-impacted ecosystems.

In November 2015, a catastrophic rupture of the Fundão dam in Mariana (Brazil), resulted in extensive socio-economic and environmental repercussions that persist to this day. In response, several reforestation programs were initiated to remediate the impacted regions. However, accurately assessing soil health in these areas is a complex endeavor. This study employs machine learning techniques to predict soil quality indicators that effectively differentiate between the stages of recovery in these areas. For this, a comprehensive set of soil parameters, encompassing 3 biological, 16 chemical, and 3 physical parameters, were evaluated for samples exposed to mining tailings and those unaffected, totaling 81 and 6 samples, respectively, which were evaluated over 2 years. The most robust model was the decision tree with a restriction of fewer levels to simplify the tree structure. In this model, Cation Exchange Capacity (CEC), Microbial Biomass Carbon (MBC), Base Saturation (BS), and Effective Cation Exchange Capacity (eCEC) emerged as the most pivotal factors influencing model fitting. This model achieved an accuracy score of 92% during training and 93% during testing for determining stages of recovery. The model developed in this study has the potential to revolutionize the monitoring efforts conducted by regulatory agencies in these regions. By reducing the number of parameters that necessitate evaluation, this enhanced efficiency promises to expedite recovery monitoring, simultaneously enhancing cost-effectiveness while upholding the analytical rigor of assessments.

Folk medicine, biological activity, and chemical profiles of Brazilian Acanthaceae (Lamiales) - A review.

INTRODUCTION: The botanical family Acanthaceae (order Lamiales) potentially comprises 4900 species in 191 genera with extensive morphological, habit and habitat diversity. The family is widely distributed throughout the world but is especially rich in tropical and subtropical regions. Many of its species have great ornamental importance and are broadly used for medicinal purposes in several countries of Asia and Africa. Brazil is a main center of diversity of the family, where they are distributed across all its biomes, mainly in the herbaceous-shrub stratum. Medicinal investigations about Brazilian species are scarce, the exception being a single native species, Justicia pectoralis Jacq., that is widely used and studied chemically. AIM OF THE REVIEW: This work compiled studies that indicated folk medicinal use, investigated biological activity, or evaluated the chemical composition of Brazilian species of Acanthaceae. MATERIAL AND METHODS: Medicinal uses, investigations of biological activities and chemical data were collected and summarized through bibliographic surveys. Tables were compiled to standardize the information and the appropriate references were gathered for each species. Registration of chemical components used in the treatment of ailments and in preserving health were emphasized with the aim of stimulating future investigations. RESULTS: The breadths of habitats and morphologies of the family are directly related to its chemical diversity, as confirmed here for Brazilian species. Although the investigated species represent less than 9% of the total richness of the family in Brazil, they encompass a great diversity of chemical substances. The data indicated folk medicinal uses for 26 species and biological tests for 23, while 30 species were investigated chemically. Ruellia and Justicia were the most researched genera with 12 and 11 species, representing approximately 14% and 7% of Brazilian species of each genus, respectively. Two species are native to other countries but become naturalized in Brazil. Studies of native species were carried out in different countries around the world, with many reports of medicinal uses and biological tests. Examples of uses include anticancer and antidepressant actions, as well as activities against respiratory problems and other diseases. CONCLUSIONS: This work highlights the chemical and biological diversity of the studied Brazilian species of Acanthaceae, which emphasizes the need to expand studies with native Brazilian species.

Contributions of human cultures to biodiversity and ecosystem conservation.

The expansion of globalized industrial societies is causing global warming, ecosystem degradation, and species and language extinctions worldwide. Mainstream conservation efforts still focus on nature protection strategies to revert this crisis, often overlooking the essential roles of Indigenous Peoples and Local Communities (IP&LC) in protecting biodiversity and ecosystems globally. Here we assess the scientific literature to identify relationships between biodiversity (including ecosystem diversity) and cultural diversity, and investigate how these connections may affect conservation outcomes in tropical lowland South America. Our assessment reveals a network of interactions and feedbacks between biodiversity and diverse IP&LC, suggesting interconnectedness and interdependencies from which multiple benefits to nature and societies emerge. We illustrate our findings with five case studies of successful conservation models, described as consolidated or promising 'social-ecological hope spots', that show how engagement with IP&LC of various cultures may be the best hope for biodiversity and ecosystem conservation, particularly when aligned with science and technology. In light of these five inspiring cases, we argue that conservation science and policies need to recognize that protecting and promoting both biological and cultural diversities can provide additional co-benefits and solutions to maintain ecosystems resilient in the face of global changes.

Intentional creation of carbon-rich dark earth soils in the Amazon.

Fertile soil known as Amazonian dark earth is central to the debate over the size and ecological impact of ancient human populations in the Amazon. Dark earth is typically associated with human occupation, but it is uncertain whether it was created intentionally. Dark earth may also be a substantial carbon sink, but its spatial extent and carbon inventory are unknown. We demonstrate spatial and compositional similarities between ancient and modern dark earth and document modern Indigenous practices that enrich soil, which we use to propose a model for the formation of ancient dark earth. This comparison suggests that ancient Amazonians managed soil to improve fertility and increase crop productivity. These practices also sequestered and stored carbon in the soil for centuries, and we show that some ancient sites contain as much carbon as the above-ground rainforest biomass. Our results demonstrate the intentional creation of dark earth and highlight the value of Indigenous knowledge for sustainable rainforest management.

Genomic history of coastal societies from eastern South America.

Sambaqui (shellmound) societies are among the most intriguing archaeological phenomena in pre-colonial South America, extending from approximately 8,000 to 1,000 years before present (yr BP) across 3,000 km on the Atlantic coast. However, little is known about their connection to early Holocene hunter-gatherers, how this may have contributed to different historical pathways and the processes through which late Holocene ceramists came to rule the coast shortly before European contact. To contribute to our understanding of the population history of indigenous societies on the eastern coast of South America, we produced genome-wide data from 34 ancient individuals as early as 10,000 yr BP from four different regions in Brazil. Early Holocene hunter-gatherers were found to lack shared genetic drift among themselves and with later populations from eastern South America, suggesting that they derived from a common radiation and did not contribute substantially to later coastal groups. Our analyses show genetic heterogeneity among contemporaneous Sambaqui groups from the southeastern and southern Brazilian coast, contrary to the similarity expressed in the archaeological record. The complex history of intercultural contact between inland horticulturists and coastal populations becomes genetically evident during the final horizon of Sambaqui societies, from around 2,200 yr BP, corroborating evidence of cultural change.

Development and implementation of a medication reconciliation during pediatric transitions of care in a public hospital.

OBJECTIVES: To generate effective changes in the work processes of an institution, such as hospitals, strategies are needed for the implementation of services. These should be based on the needs of the practice scenario and evidence that may develop programs applied to the routine of health care. This study aimed to implement medication reconciliation (MR) at the transition of care in the pediatric department of a public hospital located in Northeast Brazil. SETTING: A step-by-step approach was adopted to implement MR in the studied hospital and conducted from March 2019 to December 2019. PRACTICE INNOVATION: The implementation of MR used the "Model for Improvement" framework. The processes were built and tested in the Plan-Do-Study-Act (PDSA) cycles. Children admitted to the hospital's pediatrics department were included in the study. The objective of the PDSA cycles was to reach 75% of the patients included, with the service performed in at least one transition of care episode. EVALUATION: This study used the following indicators: number of steps performed, number of discrepancies identified, and resolution of discrepancies. Descriptive statistical analysis was performed for all variables. RESULTS: In the first cycle, all patients (n = 34) had the best possible medication history (BPMH) completed, and 26.4% went through all the MR stages. Seventy-two discrepancies were identified and 90.3% of them were resolved. In the second cycle, all patients (n = 35) had the BPMH completed, and 20% went through all the stages. A total of 32 discrepancies were identified and 96.8% of them were resolved. In the third cycle, all patients (n = 30) had the BPMH completed, and 56.6% of patients went through all the stages. Twenty-four discrepancies were identified and resolved. CONCLUSION: The use of the "Model for Improvement" framework effectively contributed to the implementation of the service according to the characteristics of the studied hospital.

Characterization of the biofilm structure and microbial diversity of sulfate-reducing bacteria from petroleum produced water supplemented by different carbon sources.

Colonization by sulfate-reducing bacteria (SRB) in environments associated with oil is mainly dependent on the availability of sulfate and carbon sources. The formation of biofilms by SRB increases the corrosion of pipelines and oil storage tanks, representing great occupational and operational risks and respective economic losses for the oil industry. The aim of this study was to evaluate the influence of the addition of acetate, butyrate, lactate, propionate and oil on the structure of biofilm formed in carbon steel coupons, as well as on the diversity of total bacteria and SRB in the planktonic and sessile communities from petroleum produced water. The biofilm morphology, chemical composition, average roughness and the microbial diversity was analyzed. In all carbon sources, formation of dense biofilm without morphological and/or microbial density differences was detected, with the most of cells observed in the form of individual rods. The diversity and richness indices of bacterial species in the planktonic community was greater than in the biofilm. Geotoga was the most abundant genus, and more than 85% of SRB species were common to all treatments. The functional predicted profile shown that the observed genres in planktonic communities were related to the reduction of sulfate, sulfite, elementary sulfur and other sulfur compounds, but the abundance varied between treatments. For the biofilm, the functions predicted profile for the oil treatment was the one that most varied in relation to the control, while for the planktonic community, the addition of all carbon sources interfered in the predicted functional profile. Thus, although it does not cause changes in the structure and morphology biofilm, the supplementation of produced water with different carbon sources is associated with changes in the SRB taxonomic composition and functional profiles of the biofilm and the planktonic bacterial communities.

A "Dirty" Footprint: Macroinvertebrate diversity in Amazonian Anthropic Soils.

Amazonian rainforests, once thought to be pristine wilderness, are increasingly known to have been widely inhabited, modified, and managed prior to European arrival, by human populations with diverse cultural backgrounds. Amazonian Dark Earths (ADEs) are fertile soils found throughout the Amazon Basin, created by pre-Columbian societies with sedentary habits. Much is known about the chemistry of these soils, yet their zoology has been neglected. Hence, we characterized soil fertility, macroinvertebrate communities, and their activity at nine archeological sites in three Amazonian regions in ADEs and adjacent reference soils under native forest (young and old) and agricultural systems. We found 673 morphospecies and, despite similar richness in ADEs (385 spp.) and reference soils (399 spp.), we identified a tenacious pre-Columbian footprint, with 49% of morphospecies found exclusively in ADEs. Termite and total macroinvertebrate abundance were higher in reference soils, while soil fertility and macroinvertebrate activity were higher in the ADEs, and associated with larger earthworm quantities and biomass. We show that ADE habitats have a unique pool of species, but that modern land use of ADEs decreases their populations, diversity, and contributions to soil functioning. These findings support the idea that humans created and sustained high-fertility ecosystems that persist today, altering biodiversity patterns in Amazonia.

Successful treatment with alectinib after crizotinib-induced hepatitis in ALK-rearranged advanced lung cancer patient: a case report.

BACKGROUND: Besides the clinical benefit of crizotinib in ALK-rearranged metastatic non-small cell lung cancer (NSCLC), concerns about its hepatotoxicity have arisen. It is not clear whether this is a drug class side effect or if the use of other selective ALKs inhibitors is safe after this serious adverse event. While evidence from clinical trials is scarce, reports of treatment after crizotinib-induces hepatitis may add to clinical decision. CASE PRESENTATION: Herein, we report a case of acute hepatitis induced by crizotinib in a 32-years-old female diagnosed with metastatic NSCLC, harboring the ALK-rearrangement. After 60 days of crizotinib therapy, the patient presented with acute hepatitis, diagnosed after investigation of non-specific symptoms, such as nausea and fatigue. Serum aspartate aminotransferase and alanine aminotransferase levels had increased from baseline to 3010 IU/L and 9145 IU/L, respectively. Total bilirubin increased up to 7.91 mg/dL, but she did not develop liver failure. After crizotinib discontinuation, a gradual hepatic function recovery occurred. Unfortunately, during the period without specific oncology treatment, her disease showed an unequivocal progression. Therefore, she started on alectinib with great response, and no liver function alteration recurred. CONCLUSIONS: This case suggests that alectinib, even belonging to the same drug class, could be used as an alternative agent when crizotinib is the etiology of liver damage, but more robust evidence has awaited.

Chemosystematic and evolutionary trends of the genistoid clade sensu stricto (Papilionoideae, Fabaceae).

The Papilionoideae, which comprises 503 genera and approximately 14,000 species, is the largest and most diverse subfamily of the Fabaceae family. In this subfamily, the Crotalarieae, Genisteae, Podalyrieae, Thermopsideae, Sophoreae and Euchresteae tribes are closely related by micro and macromolecular features, thus forming the genistoid clade. This group combines well-known genera, whereas other genera lack phytochemical and chemotaxonomic studies. Thus, this work aimed to characterize the special metabolites in these genera in order to define the chemical profile, the micromolecular markers and the chemical diversity, as well as to evaluate the group evolutionary trends. Flavonoids and alkaloids were identified as chemosystematic markers for the studied tribes due to high occurrence number and structural diversity. Among flavonoids, the flavones and isoflavones predominated. Low protection indexes of flavonoid hydroxyls by O-glycosylation or O-methylation were observed, whereas C-prenylation and C-glycosylation were frequent, mainly at C-6 and C-8 positions. The flavone/flavonol ratio shows the predominance of the flavones. Quinolizidine and piperidine alkaloids were present in most genera. Pyrrolizidine alkaloids were found in a few genera from Thermopsideae, Genisteae and Crotalarieae, which suggests a mechanism of adaptive convergence. Cluster analysis allowed separation of genera for each tribe by chemical similarities. The micromolecular trends of protection of flavonoid hydroxyls and alkaloid oxidation indicate the genistoid clade is through evolutionary transition, which is consistent with its phylogenetic position in the Papilionoideae subfamily.

Prevalence of medication discrepancies in pediatric patients transferred between hospital wards.

Background Children are more susceptible to harm from medication errors and adverse drug reactions when compared to adults. Such events may occur from medication discrepancies while transitioning patients throughout the healthcare system. Contributing factors include medication discontinuity and lack of information by the healthcare team. Objective To analyze the prevalence of medication discrepancies in transition points of care in a pediatric department. Setting Pediatric department of a public hospital in Northeast Brazil. Method A cross-sectional study was carried out from August 2017 to March 2018. Data collection consisted of the following steps: collection of sociodemographic data, clinical interview with the patient's caregiver, registration of patient prescriptions, and evaluation of medical records. Medication discrepancies were classified as intentional and unintentional. The unintentional medication discrepancies were classified as omission of medication, therapeutic duplicity, and differences in dose, frequency, or route of administration. Main outcomes measure Discrepancy profile identified at admission, internal transfer and hospital discharge. Results Among the 114 patients included in the study, 85 (74.5%) patients had at least one unintentional medication discrepancy, of which 16 (14.0%) patients presented medication discrepancies at hospital admission, 42 (36.8%) patients at internal transfer, and 52 (45.6%) patients during discharge. Omission of medication represented 20 (74.1%) errors at admission, 26 (37.7%) errors at internal transfer, and 80 (100.0%) errors at hospital discharge. Conclusions The main transition points of care where unintentional discrepancies occurred in the studied pediatric department were at internal transfer and hospital discharge, with omission being the most common type of unintentional discrepancy.

Cross-cultural adaptation, factor structure, and evidence of reliability of the Smartphone Addiction Scale in Brazil

Objective: To translate, adapt, and examine the factor structure and internal consistency of a Brazilian Portuguese version of the Smartphone Addiction Scale (SAS-BR) among university students. Methods: The SAS was translated and adapted for use with Brazilian samples. The resulting instrument (SAS-BR) was then administered to 356 college students. Parallel analysis was used to explore the maximum number of dimensions that underlie the assessment, and data modeling was undertaken using exploratory multidimensional item response theory (E-MIRT). The reliability of the SAS-BR was tested by computing McDonald's omega (ω) and Cronbach's alpha (α) coefficients. Results: Parallel analysis revealed a maximum of six factors. E-MIRT analysis revealed that a five-factor model was the best fit for the data. The five emergent factors were salience, positive anticipation, cyberspace-oriented relationship, preoccupation with smartphone, and physical symptoms; these factors together explained 50% of the variance. Confirmatory factor analysis, conducted using data from a second sample, replicated the five-factor structure. The internal consistency of the scale was found to be strong. Conclusion: The emergent factor structure of the SAS-BR was found to be similar to that of previous adaptations of this instrument for other Western countries.

Cross-cultural adaptation, factor structure, and evidence of reliability of the Smartphone Addiction Scale in Brazil.

OBJECTIVE: To translate, adapt, and examine the factor structure and internal consistency of a Brazilian Portuguese version of the Smartphone Addiction Scale (SAS-BR) among university students. METHODS: The SAS was translated and adapted for use with Brazilian samples. The resulting instrument (SAS-BR) was then administered to 356 college students. Parallel analysis was used to explore the maximum number of dimensions that underlie the assessment, and data modeling was undertaken using exploratory multidimensional item response theory (E-MIRT). The reliability of the SAS-BR was tested by computing McDonald's omega (ω) and Cronbach's alpha (α) coefficients. RESULTS: Parallel analysis revealed a maximum of six factors. E-MIRT analysis revealed that a five-factor model was the best fit for the data. The five emergent factors were salience, positive anticipation, cyberspace-oriented relationship, preoccupation with smartphone, and physical symptoms; these factors together explained 50% of the variance. Confirmatory factor analysis, conducted using data from a second sample, replicated the five-factor structure. The internal consistency of the scale was found to be strong. CONCLUSION: The emergent factor structure of the SAS-BR was found to be similar to that of previous adaptations of this instrument for other Western countries.

Predictors of problematic smartphone use among university students.

Predictors of problematic smartphone use have been found mainly in studies on elementary and high school students. Few studies have focused on predictors related to social network and messaging apps or smartphone model. Thus, the objective of our study was to identify predictors of problematic smartphone use related to demographic characteristics, loneliness, social app use, and smartphone model among university students. This cross-sectional study involved 257 Brazilian university students who answered a smartphone addiction scale, a questionnaire about smartphone usage patterns, and the Brazilian version of the UCLA-R loneliness scale. Women, iPhone owners, and users of Instagram and Snapchat had significantly higher smartphone addiction scores. We found correlations between scores for the Brazilian version of smartphone addiction scale and the importance attributed to WhatsApp, Facebook, Instagram, and Snapchat, and the Brazilian version of the UCLA-R loneliness scale. Our hierarchical regression model predicted 32.2% of the scores of the Brazilian version of the smartphone addiction scale, with the greatest increase in predictive capability by the step that added smartphone social app importance, followed by the step that added loneliness. Adding the smartphone model produced the smallest increase in predictive capability. The theoretical and practical implications of these results are discussed.

Evaluation of the Phytotoxicity of Urochloa humidicola Roots by Bioassays and Microscopic Analysis. Characterization of New Compounds.

Herbicides are a key element in agriculture but they do cause environmental problems and natural alternatives are being sought. In this context, invasive plants could provide an as yet unexplored source for the development of future herbicides. Urochloa humidicola has great invasive potential in Brazilian environments as it hampers the establishment of other plants. The phytotoxicity of U. humidicola root extracts has been evaluated, and the major components have been identified. The phytotoxicity of the extract was assessed in the wheat coleoptile assay on seeds of troublesome weeds and on Anadenanthera colubrina, a tree species used in ecological restoration programs. The ethyl acetate extract showed the highest activity, and the most affected weeds were E. crus-galli, M. maximus, and A. viridis with the latter weed more affected by the extract than by the herbicide Logran. Microscopic ultrastructural analysis of A. colubrina roots indicated possible signals of cell death. Seven compounds were identified in the ethyl acetate extract of which one diterpene and four saponins are new. Six of these compounds were tested in the wheat coleoptile bioassay. The most active were diterpene 1 and saponins 2, 3, and 6. The phytotoxic activity of U. humidicola explains the issues observed in ecological restoration with A. colubrina in the presence of Urochloa species, and its effect on weeds reinforces its potential use in agriculture.

Physicochemical characterization of Pseudomonas stutzeri UFV5 and analysis of its transcriptome under heterotrophic nitrification/aerobic denitrification pathway induction condition.

Biological ammonium removal via heterotrophic nitrification/aerobic denitrification (HN/AD) presents several advantages in relation to conventional removal processes, but little is known about the microorganisms and metabolic pathways involved in this process. In this study, Pseudomonas stutzeri UFV5 was isolated from an activated sludge sample from oil wastewater treatment station and its ammonium removal via HN/AD was investigated by physicochemical and molecular approaches to better understand this process and optimize the biological ammonium removal in wastewater treatment plants. Results showed that P. stutzeri UFV5 removed all the ammonium in 48-72 hours using pyruvate, acetate, citrate or sodium succinate as carbon sources, C/N ratios 6, 8, 10 and 12, 3-6% salinities, pH 7-9 and temperatures of 20-40 °C. Comparative genomics and PCR revealed that genes encoding the enzymes involved in anaerobic denitrification process are present in P. stutzeri genome, but no gene that encodes enzymes involved in autotrophic nitrification was found. Furthermore, transcriptomics showed that none of the known enzymes of autotrophic nitrification and anaerobic denitrification had their expression differentiated and an upregulation of the biosynthesis machinery and protein translation was observed, besides several genes with unknown function, indicating a non-conventional mechanism involved in HN/AD process.

Predictors of problematic smartphone use among university students

Abstract Predictors of problematic smartphone use have been found mainly in studies on elementary and high school students. Few studies have focused on predictors related to social network and messaging apps or smartphone model. Thus, the objective of our study was to identify predictors of problematic smartphone use related to demographic characteristics, loneliness, social app use, and smartphone model among university students. This cross-sectional study involved 257 Brazilian university students who answered a smartphone addiction scale, a questionnaire about smartphone usage patterns, and the Brazilian version of the UCLA-R loneliness scale. Women, iPhone owners, and users of Instagram and Snapchat had significantly higher smartphone addiction scores. We found correlations between scores for the Brazilian version of smartphone addiction scale and the importance attributed to WhatsApp, Facebook, Instagram, and Snapchat, and the Brazilian version of the UCLA-R loneliness scale. Our hierarchical regression model predicted 32.2% of the scores of the Brazilian version of the smartphone addiction scale, with the greatest increase in predictive capability by the step that added smartphone social app importance, followed by the step that added loneliness. Adding the smartphone model produced the smallest increase in predictive capability. The theoretical and practical implications of these results are discussed.