Synthesis, Photophysical Properties, Theoretical Studies, and Living Cancer Cell Imaging Applications of New 7-(Diethylamino)quinolone Chalcones.

In this article, three unsymmetrical 7-(diethylamino)quinolone chalcones with D-π-A-D and D-π-A-π-D type push-pull molecular arrangements were synthesized via a Claisen-Schmidt reaction. Using 7-(diethylamino)quinolone and vanillin as electron donor (D) moieties, these were linked together through the α,ß-unsaturated carbonyl system acting as a linker and an electron acceptor (A). The photophysical properties were studied, revealing significant Stokes shifts and strong solvatofluorochromism caused by the ICT and TICT behavior produced by the push-pull effect. Moreover, quenching caused by the population of the TICT state in THF-H2O mixtures was observed, and the emission in the solid state evidenced a red shift compared to the emission in solution. These findings were corroborated by density functional theory (DFT) calculations employing the wb97xd/6-311G(d,p) method. The cytotoxic activity of the synthesized compounds was assessed on BHK-21, PC3, and LNCaP cell lines, revealing moderate activity across all compounds. Notably, compound 5b exhibited the highest activity against LNCaP cells, with an LC50 value of 10.89 µM. Furthermore, the compounds were evaluated for their potential as imaging agents in living prostate cells. The results demonstrated their favorable cell permeability and strong emission at 488 nm, positioning them as promising candidates for cancer cell imaging applications.

Bilateral Subcutaneous Pedicled Nasolabial Island Flap for Total Reconstruction of the Lower Lip.

Squamous cell carcinomas are the most common cancer of the lower lip. In most cases, the tumor is small and occupies less than a third of the lower lip, so the defect created can be closed with a primary suture without altering the esthetics and function of the lower lip. However, there is a percentage of large tumors that affect more than two thirds of the lower lip, in which the primary suture is insufficient to correct the defect created by resection of the tumor. Therefore, these cases require more complex reconstructions using facial locoregional flaps. Hence, in this article, the authors present a total reconstruction of the lower lip with a bilateral subcutaneous pedicled nasolabial island flap after complete resection of a squamous cell carcinoma with involvement of the entire lower lip.

Vibrational microspectroscopy as a tool to unveil new chemotherapeutic strategies against osteosarcoma.

Over the years, osteosarcoma therapy has had a significative improvement with the use of a multidrug regime strategy, increasing the survival rates from less than 20 % to circa 70 %. Different types of development of new antineoplastic agents are critical to achieve irreversible damage to cancer cells, while preserving the integrity of their healthy counterparts. In the present study, complexes with two and three Pd(II) centres linked by the biogenic polyamines: spermine (Pd2SpmCl4) and spermidine (Pd3Spd2Cl6) were tested against non-malignant (osteoblasts, HOb) and cancer (osteosarcoma, MG-63) human cell lines. Either alone or in combination according to the EURAMOS-1 protocol, they were used versus cisplatin as a drug reference. By evaluating the cytotoxic effects of both therapeutic approaches (single and drug combination) in HOb and MG-63 cell lines, the selective anti-tumoral potential is assessed. To understand the different treatments at a molecular level, Synchrotron Radiation Fourier Transform Infrared and Raman microspectroscopies were applied. Principal component analysis and hierarchical cluster analysis are applied to the vibrational data, revealing the major metabolic changes caused by each drug, which were found to rely on DNA, lipids, and proteins, acting as biomarkers of drug-to-cell impact. The main changes were observed for the B-DNA native conformation to either Z-DNA (higher in the presence of polynuclear complexes) or A-DNA (preferably after cisplatin exposure). Additionally, a higher effect upon variation in proteins content was detected in drug combination when compared to single drug administration proving the efficacy of the EURAMOS-1 protocol with the new drugs tested.

Use of Tirzepatide in Adults with Type 2 Diabetes Mellitus: Scientific Evidence and Practical Aspects.

Tirzepatide is a novel antidiabetic medication a single-molecule, agonist to the glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptors. It is approved in the USA and EU for the treatment of type 2 diabetes mellitus (T2DM) and obesity. Due to the potential novelty represented by incorporating tirzepatide to clinical practice, we aim to review practical aspects of tirzepatide use in T2DM and the supporting scientific evidence. A group of ten endocrinologists involved as investigators in the phase 3 SURPASS clinical trial program followed a nominal group technique, a qualitative research methodology designed as a semi-structured group discussion to reach a consensus on the selection of a set of practical aspects. The scientific evidence for tirzepatide has been reviewed with respect to a number of patients' clinical profiles and care goals. Information of interest related to adverse events, special warnings and precautions, and other considerations for tirzepatide use has been included. Finally, information provided to the patients has been summarized. The practical aspects reported herein may be helpful in guiding physicians in the use of tirzepatide and contribute to optimizing the management of T2DM.

Uncovering physical activity trade-offs in transportation policy: A spatial agent-based model of Bogotá, Colombia.

BACKGROUND: Transportation policies can impact health outcomes while simultaneously promoting social equity and environmental sustainability. We developed an agent-based model (ABM) to simulate the impacts of fare subsidies and congestion taxes on commuter decision-making and travel patterns. We report effects on mode share, travel time and transport-related physical activity (PA), including the variability of effects by socioeconomic strata (SES), and the trade-offs that may need to be considered in the implementation of these policies in a context with high levels of necessity-based physical activity. METHODS: The ABM design was informed by local stakeholder engagement. The demographic and spatial characteristics of the in-silico city, and its residents, were informed by local surveys and empirical studies. We used ridership and travel time data from the 2019 Bogotá Household Travel Survey to calibrate and validate the model by SES. We then explored the impacts of fare subsidy and congestion tax policy scenarios. RESULTS: Our model reproduced commuting patterns observed in Bogotá, including substantial necessity-based walking for transportation. At the city-level, congestion taxes fractionally reduced car use, including among mid-to-high SES groups but not among low SES commuters. Neither travel times nor physical activity levels were impacted at the city level or by SES. Comparatively, fare subsidies promoted city-level public transportation (PT) ridership, particularly under a 'free-fare' scenario, largely through reductions in walking trips. 'Free fare' policies also led to a large reduction in very long walking times and an overall reduction in the commuting-based attainment of physical activity guidelines. Differential effects were observed by SES, with free fares promoting PT ridership primarily among low-and-middle SES groups. These shifts to PT reduced median walking times among all SES groups, particularly low-SES groups. Moreover, the proportion of low-to-mid SES commuters meeting weekly physical activity recommendations decreased under the 'freefare' policy, with no change observed among high-SES groups. CONCLUSIONS: Transport policies can differentially impact SES-level disparities in necessity-based walking and travel times. Understanding these impacts is critical in shaping transportation policies that balance the dual aims of reducing SES-level disparities in travel time (and time poverty) and the promotion of choice-based physical activity.

Brief Report: Updated Data From IMscin001 Part 2, a Randomized Phase III Study of Subcutaneous Versus Intravenous Atezolizumab in Patients With Locally Advanced/Metastatic NSCLC.

INTRODUCTION: Subcutaneous atezolizumab is approved for the treatment of various solid tumors. Previous results from the IMscin001 study (NCT03735121) demonstrated that the pharmacokinetics, efficacy, immunogenicity, and safety of subcutaneous and intravenous atezolizumab were consistent (data cutoff: April 26, 2022). We present updated data from this trial (data cut-off: 16 January 2023). METHODS: Eligible patients aged ≥18 years with locally advanced/metastatic NSCLC were randomized (2:1) to receive atezolizumab subcutaneously (1875 mg, n=247) or intravenously (1200 mg, n=124) every 3 weeks. Here we present updated efficacy (overall survival [OS]; progression-free survival; objective response rate; duration of response), safety, and immunogenicity endpoints, alongside patient-reported outcomes (PROs) and healthcare practitioner (HCP) perspectives. RESULTS: In this updated analysis, the median survival follow-up was 9.5 months. Median subcutaneous injection time was 7.1 minutes, with an average subcutaneous injection time of 4-8 minutes in most patients (75.7%). OS data were mature: median OS was similar between treatment arms, at 10.7 and 10.1 months in the subcutaneous and intravenous arms, respectively (HR: 0.88; 95% CI: 0.67-1.16). Other efficacy endpoints, as well as immunogenicity, PROs, and safety, were similar between arms. Most HCPs found subcutaneous administration convenient (79.5%), easy to administer (89.7%), and were satisfied with the treatment (84.6%); 75.0% of HCPs agreed that administering atezolizumab subcutaneously compared with intravenously could save time. CONCLUSIONS: In this analysis, mature OS data were similar between treatments. The updated efficacy and safety profile of subcutaneous atezolizumab is consistent with previous findings and equivalent to intravenous atezolizumab.

Clinical Characteristics and Outcomes of Disseminated Strongyloidiasis in the United States-A Multicenter Network Analysis.

Human strongyloidiasis is a potentially life-threatening parasitic disease among immunocompromised hosts. We aim to determine the factors and mortality associated with disseminated strongyloidiasis. We conducted a U.S.-based multicenter retrospective cohort study to determine 90-day clinical outcomes for people diagnosed with Strongyloides infection in the TriNetX patient database. We identified adult patients with the International Classification of Diseases (10th revision, clinical modification) code for Strongyloides infection (B78) or a positive Strongyloides IgG antibody test and captured outcomes at 90 days. We identified 5,434 patients with strongyloidiasis, of whom 48 had disseminated strongyloidiasis for 0.9% prevalence of disseminated disease. Systemic connective tissue disorders, pulmonary eosinophilia, liver cirrhosis, blood disorders (monoclonal gammopathy, aplastic anemia, and lymphoid malignancy), malnutrition, alcohol use disorder, and transplantation status were frequent in patients with disseminated disease. Mortality was significantly higher in people with disseminated disease at 30 days (21%). The 90-day risk of hospitalization, bacteremia, and acute respiratory distress syndrome (ARDS) was higher in those with disseminated infection. People with disseminated strongyloidiasis had a heightened risk of hospitalization, bacteremia, acute respiratory distress syndrome, and mortality. The population at risk for severe strongyloidiasis infection is evolving, reflecting conditions in which glucocorticoids or additional immunosuppressive medications are commonly used for treatment.

Eating Behaviours and Dietary Intake in Children and Adolescents: A Systematic Review.

PURPOSE OF REVIEW: This systematic review aimed to examine existing evidence related to associations between eating behaviours and dietary intake in children and adolescents, with a focus on the Children Eating Behaviour Questionnaire (CEBQ) and the Dutch Eating Behaviour Questionnaire (DEBQ) as assessment tools. RECENT FINDING: We conducted a systematic review following PRISMA guidelines. We included observational and interventional studies published in English, Spanish, or Portuguese, that evaluated the association between eating behaviours and food and beverage intake. Thirteen studies from nine countries met the inclusion criteria, with sample sizes ranging from 62 to 4,914 individuals aged 2 to 16 years-old. Ten studies used the CEBQ, and three used the DEBQ. Our retrieved studies showed that children and adolescents engaging in food approach behaviours tend to consume foods rich in sugar and fats. However, we observed a higher consumption of fruits and vegetables. On the other hand, children and adolescents with lower engagement to food avoidant behaviours, generally exhibited a lower overall food consumption, except for snacks, which they consumed at a higher rate. This systematic review suggests that eating behaviours play an important role in shaping dietary intake. Nevertheless, due to the heterogeneity related to eating behaviours and diet intake, it highlights the need for further research to understand these complex relationships to develop effective interventions for promoting healthy eating habits in children and adolescents.

Impact of Living Donor Liver Transplantation on the Improvement of Hepatocellular Carcinoma Treatment.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths, with increasing incidence. There are different treatment options, but only 30%-40% of HCC cases are diagnosed at an early stage for curative treatment. With the implementation of Milan Criteria for liver transplantation (LT) in HCC cases and its use for organ allocation with successful outcomes, LT has become an optimal treatment. Seeking new criteria for LT and developing updated algorithms for HCC treatment has become a hot topic nowadays. With the experience in living donor liver transplantation (LDLT), especially in Asian countries, LDLT was established and adopted with different criteria for HCC treatment, especially including criteria beyond Milan's size and number of tumors. Living donor grafts are uniquely different than deceased donor grafts as they are not considered a public resource. A living donor graft is rather a private gift intended for a specific recipient. Living donor livers are not limited by organ allocation systems, and this significant advantage of LDLT has opened new frontiers in the treatment of HCC. Improvements in LDLT have had remarkable parallel effects in the successful treatment of HCC as supported by a growing body of literature in the past decade.

Personalized medicine and nutrition in hepatology for preventing chronic liver disease in Mexico.

Chronic liver disease is a global health issue. Patients with chronic liver disease require a fresh approach that focuses on the genetic and environmental factors that contribute to disease initiation and progression. Emerging knowledge in the fields of Genomic Medicine and Genomic Nutrition demonstrates differences between countries in terms of genetics and lifestyle risk factors such as diet, physical activity, and mental health in chronic liver disease, which serves as the foundation for the implementation of Personalized Medicine and Nutrition (PerMed-Nut) strategies. Most of the world's populations have descended from various ethnic groupings. Mexico's population has a tripartite ancestral background, consisting of Amerindian, European, and African lineages, which is common across Latin America's regional countries. The purpose of this review is to discuss the genetic and environmental components that could be incorporated into a PerMed-Nut model for metabolic-associated liver disease, viral hepatitis B and C, and hepatocellular carcinoma in Mexico. Additionally, the implementation of the PerMed-Nut approach will require updated medicine and nutrition education curricula. Training and equipping future health professionals and researchers with new clinical and investigative abilities focused on preventing liver illnesses in the field of genomic hepatology globally is a vision that clinicians and nutritionists should be concerned about.

Association of Antithrombotic Drug Use With Incident Intracerebral Hemorrhage Location.

BACKGROUND AND OBJECTIVES: Few population-based studies have assessed associations between the use of antithrombotic (platelet antiaggregant or anticoagulant) drugs and location-specific risks of spontaneous intracerebral hemorrhage (s-ICH). In this study, we estimated associations between antithrombotic drug use and the risk of lobar vs nonlobar incident s-ICH. METHODS: Using Danish nationwide registries, we identified cases in the Southern Denmark Region of first-ever s-ICH in patients aged 50 years or older between 2009 and 2018. Each verified case was classified as lobar or nonlobar s-ICH and matched to controls in the general population by age, sex, and calendar year. Prior antithrombotic use was ascertained from a nationwide prescription registry. We calculated odds ratios (aORs) for associations between the use of clopidogrel, aspirin, direct oral anticoagulants (DOACs) or vitamin K antagonists (VKA), and lobar and nonlobar ICH in conditional logistic regression analyses that were adjusted for potential confounders. RESULTS: A total of 1,040 cases of lobar (47.9% men, mean age [SD] 75.2 [10.7] years) and 1,263 cases of nonlobar s-ICH (54.2% men, mean age 73.6 [11.4] years) were matched to 41,651 and 50,574 controls, respectively. A stronger association with lobar s-ICH was found for clopidogrel (cases: 7.6%, controls: 3.5%; aOR 3.46 [95% CI 2.45-4.89]) vs aspirin (cases: 22.9%, controls: 20.4%; aOR 2.14 [1.74-2.63; p = 0.019). Corresponding estimates for nonlobar s-ICH were not different between clopidogrel (cases: 5.4%, controls: 3.4%; aOR 2.44 [1.71-3.49]) and aspirin (cases: 20.7%, controls: 19.2%; aOR 1.77 [1.47-2.15]; p = 0.12). VKA use was associated with higher odds of both lobar (cases: 14.3%, controls: 6.1%; aOR 3.66 [2.78-4.80]) and nonlobar (cases: 15.4%, controls: 5.5%; aOR 4.62 [3.67-5.82]) s-ICH. The association of DOAC use with lobar s-ICH (cases: 3.5%, controls: 2.7%; aOR 1.66 [1.02-2.70]) was weaker than that of VKA use (p = 0.006). Corresponding estimates for nonlobar s-ICH were not different between DOACs (cases: 5.1%, controls: 2.4%; aOR 3.44 [2.33-5.08]) and VKAs (p = 0.20). DISCUSSION: Antithrombotics were associated with higher risks of s-ICH, but the strength of the associations varied by s-ICH location and drug, which may reflect differences in the cerebral microangiopathies associated with lobar vs nonlobar hemorrhages and the mechanisms of drug action.

Molecular survey of Piroplasmida, Hepatozoon spp. and Anaplasmataceae in anemic and thrombocytopenic dogs from Uruguay.

Canine tick-borne diseases, such as babesiosis, rangeliosis, hepatozoonosis, anaplasmosis and ehrlichiosis, are of veterinarian relevance, causing mild or severe clinical cases that can lead to the death of the dog. The aim of this study was detecting tick-borne protozoan and rickettsial infections in dogs with anemia and/or thrombocytopenia in Uruguay. A total of 803 domestic dogs were evaluated, and 10% were found positive (detected by PCR) at least for one hemoparasite. Sequence analysis confirmed the presence of four hemoprotozoan species: Rangelia vitalii, Babesia vogeli, Hepatozoon canis and Hepatozoon americanum, and the rickettsial Anaplasma platys. The most detected hemoparasite was R. vitalii, followed by H. canis and A. platys. This is the first report of B. vogeli in Uruguay and the second report of H. americanum in dogs from South America. The results highlight the importance for veterinarians to include hemoparasitic diseases in their differential diagnosis of agents causing anemia and thrombocytopenia.

The hormonal profile in women using oral contraceptives is not as stable as previously thought: a temporal analysis of serum endogenous and exogenous hormones.

Oral contraceptive pills are used by approximately 250 million women worldwide, however a clear understanding of the concentrations of endogenous and exogenous hormones across a 28-day oral contraceptive pill pack is not well described. In our study of 16 female participants taking various monophasic oral contraceptive pills, we found significant fluctuations in endogenous and exogenous hormone levels throughout the pill cycle, challenging the previous assumption of hormonal stability in oral contraceptive users. The results from this study have wide ranging implications for research and treatment in women's health including: considerations in research design and interpretation for studies including women taking oral contraceptives, the potential for more precise and personalized methods of dosing to reduce unwanted side effects and adverse events, and the potential treatment of a variety of disorders ranging from musculoskeletal to neurological with exogenous hormones.

Opposing effects of the purinergic P2X7 receptor on seizures in neurons and microglia in male mice.

BACKGROUND: The purinergic ATP-gated P2X7 receptor (P2X7R) is increasingly recognized to contribute to pathological neuroinflammation and brain hyperexcitability. P2X7R expression has been shown to be increased in the brain, including both microglia and neurons, in experimental models of epilepsy and patients. To date, the cell type-specific downstream effects of P2X7Rs during seizures remain, however, incompletely understood. METHODS: Effects of P2X7R signaling on seizures and epilepsy were analyzed in induced seizure models using male mice including the kainic acid model of status epilepticus and pentylenetetrazole model and in male and female mice in a genetic model of Dravet syndrome. RNA sequencing was used to analyze P2X7R downstream signaling during seizures. To investigate the cell type-specific role of the P2X7R during seizures and epilepsy, we generated mice lacking exon 2 of the P2rx7 gene in either microglia (P2rx7:Cx3cr1-Cre) or neurons (P2rx7:Thy-1-Cre). To investigate the protective potential of overexpressing P2X7R in GABAergic interneurons, P2X7Rs were overexpressed using adeno-associated virus transduction under the mDlx promoter. RESULTS: RNA sequencing of hippocampal tissue from wild-type and P2X7R knock-out mice identified both glial and neuronal genes, in particular genes involved in GABAergic signaling, under the control of the P2X7R following seizures. Mice with deleted P2rx7 in microglia displayed less severe acute seizures and developed a milder form of epilepsy, and microglia displayed an anti-inflammatory molecular profile. In contrast, mice lacking P2rx7 in neurons showed a more severe seizure phenotype when compared to epileptic wild-type mice. Analysis of single-cell expression data revealed that human P2RX7 expression is elevated in the hippocampus of patients with temporal lobe epilepsy in excitatory and inhibitory neurons. Functional studies determined that GABAergic interneurons display increased responses to P2X7R activation in experimental epilepsy. Finally, we show that viral transduction of P2X7R in GABAergic interneurons protects against evoked and spontaneous seizures in experimental temporal lobe epilepsy and in mice lacking Scn1a, a model of Dravet syndrome. CONCLUSIONS: Our results suggest a dual and opposing action of P2X7R in epilepsy and suggest P2X7R overexpression in GABAergic interneurons as a novel therapeutic strategy for acquired and, possibly, genetic forms of epilepsy.

Identifying drivers of non-stationary climate-growth relationships of European beech.

The future performance of the widely abundant European beech (Fagus sylvatica L.) across its ecological amplitude is uncertain. Although beech is considered drought-sensitive and thus negatively affected by drought events, scientific evidence indicating increasing drought vulnerability under climate change on a cross-regional scale remains elusive. While evaluating changes in climate sensitivity of secondary growth offers a promising avenue, studies from productive, closed-canopy forests suffer from knowledge gaps, especially regarding the natural variability of climate sensitivity and how it relates to radial growth as an indicator of tree vitality. Since beech is sensitive to drought, we in this study use a drought index as a climate variable to account for the combined effects of temperature and water availability and explore how the drought sensitivity of secondary growth varies temporally in dependence on growth variability, growth trends, and climatic water availability across the species' ecological amplitude. Our results show that drought sensitivity is highly variable and non-stationary, though consistently higher at dry sites compared to moist sites. Increasing drought sensitivity can largely be explained by increasing climatic aridity, especially as it is exacerbated by climate change and trees' rank progression within forest communities, as (co-)dominant trees are more sensitive to extra-canopy climatic conditions than trees embedded in understories. However, during the driest periods of the 20th century, growth showed clear signs of being decoupled from climate. This may indicate fundamental changes in system behavior and be early-warning signals of decreasing drought tolerance. The multiple significant interaction terms in our model elucidate the complexity of European beech's drought sensitivity, which needs to be taken into consideration when assessing this species' response to climate change.

Seroprevalence of Toxoplasma gondii, risk factors and knowledge about toxoplasmosis in undergraduate students from Lima, Peru.

Toxoplasma gondii is the causative agent of toxoplasmosis, a zoonotic disease of worldwide distribution. The aim of this study was to assess the seroprevalence of T. gondii in undergraduate students from Lima, Peru, and to identify the risk factors linked to the infection. For this, serum samples of 100 undergraduate students of the Faculty of Biological Sciences were tested for T. gondii antibodies with a commercially available ELISA. The seroprevalence of T. gondii in these subjects was 7 %. Only the age of students showed a statistical association with T. gondii seropositivity. The level of awareness regarding toxoplasmosis was also investigated. In the sample, 71 % of the students are aware of toxoplasmosis and 64 % that a parasite is the cause of the infection. Most know it is transmitted through undercooked meat (57 %), but are unaware of contaminated vegetables (40 %), organ transplants (17 %), blood transfusions (32 %), and soil contact (39 %). In the epidemiological context it will be valuable to verify toxoplasmosis awareness in other population groups and other regions in Peru.

Jugular Foramen Paragangliomas.

Paragangliomas are the most common tumors at jugular foramen and pose a great surgical challenge. Careful clinical history and physical examination must be performed to adequately evaluate neurological deficits and its chronologic evolution, also to delineate an overview of the patient performance status. Complete imaging evaluation including MRI and CT scans should be performed, and angiography is a must to depict tumor blood supply and sigmoid sinus/internal jugular vein patency. Screening for multifocal paragangliomas is advisable, with a whole-body imaging. Laboratory investigation of endocrine function of the tumor is necessary, and adrenergic tumors may be associated with synchronous lesions. Preoperative prepare with alpha-blockage is advisable in norepinephrine/epinephrine-secreting tumors; however, it is not advisable in exclusively dopamine-secreting neoplasms. Best surgical candidates are young otherwise healthy patients with smaller lesions; however, treatment should be individualized each case. Variations of infratemporal fossa approach are employed depending on extensions of the mass. Regarding facial nerve management, we avoid to expose or reroute it if there is preoperative function preservation and prefer to work around facial canal in way of a fallopian bridge technique. If there is preoperative facial nerve compromise, the mastoid segment of the nerve is exposed, and it may be grafted if invaded or just decompressed. A key point is to preserve the anteromedial wall of internal jugular vein if there is preoperative preservation of lower cranial nerves. Careful multilayer closure is essential to avoid at most cerebrospinal fluid leakage. Residual tumors may be reoperated if growing and presenting mass effect or be candidate for adjuvant stereotactic radiosurgery.

Circadian rhythm of salivary and serum urea concentration in alpacas and sheep receiving diets with different levels of protein.

All vertebrates possess a daily rhythm, encompassing a comprehensive set of physiological, cognitive, and behavioral patterns that manifest throughout a 24-hour period. The aim of this study was to compare the effect of crude protein (CP) levels in the diet on the daily rhythm of urea in serum (US) and saliva in alpacas and sheep. Ten alpacas and ten sheep, adult, clinically healthy males, were used; they were maintained in natural light conditions and fed ad libitum with two levels of CP (16 and 7%). Blood and saliva samples were taken every 4 h for 48 h. A two-way ANOVA was conducted to analyze the parameters, including adjusted mean rhythm (MESOR), amplitude, and acrophase. It was found that both US and saliva urea exhibited circadian rhythms with a peak during the midday (10:59 - 12:16 h). The MESOR with low CP diets was higher (P < 0.05) in alpacas. The MESOR of urea levels in saliva was greater (P < 0.05) at the highest level of CP in the diet, with no differences between alpacas and sheep (P > 0.05). The amplitude was greater (P < 0.05) in alpacas and at the high level of CP compared to the low level of CP in the diet. Our findings reveal that both serum and saliva urea levels in alpacas and sheep follow a daily rhythm and the MESOR of US was higher in alpacas when they consume food with low CP content, and this difference disappears when CP levels are increased in the diet.