We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
To simulate the impact of a price subsidy (price reduction) on purchases of healthy foods with suboptimal consumption.
Design:
We used data from the 2018 Mexican National Household Income and Expenditure Survey, a cross-sectional study. We estimated own- and cross-price elasticities of the demand for food groups using a Linear Approximation of an Almost Ideal Demand System. Using the estimated elasticities, we derived changes in purchases associated with a 10, 20 and 30 % price reduction in healthy food groups with suboptimal consumption. We also estimated price reductions for these food groups that would meet the recommendations of the Healthy Reference Diet (EAT-HRD) proposed by the EAT-Lancet commission.
Setting:
Mexico (country).
Participants:
A nationally representative sample of mexican households.
Results:
Price reductions were associated with increases in the quantity purchased, ranging from 9·4 to 28·3 % for vegetables, 7·9 to 23·8 % for fruits, 0·8 to 2·5 % for legumes and 6·0 to 18·0 % for fish. Higher reductions in prices would be needed to achieve the EAT-Lancet Commission’s recommendations for food groups with suboptimal consumption in Mexico: a 39·7 % reduction in prices for fruits, 20·0 % for vegetables and 118·7 % for legumes.
Conclusions:
Our study shows that reductions in prices can lead to increases in purchases of healthier food options. More research is needed to assess the most cost-effective strategy to deliver subsidies using either conditional cash transfers, vouchers or food baskets provided to families or direct subsidies to producers.
This paper analyzes if men and women are expected to behave differently regarding altruism. Since the dictator game provides the most suitable design for studying altruism and generosity in the lab setting, we use a modified version to study the beliefs involved in the game. Our results are substantial: men and women are expected to behave differently. Moreover, while women believe that women are more generous, men consider that women are as generous as men.
English as a second language (L2) has become the medium of instruction in numerous contexts even though many people may have difficulties to read and study in L2. According to the self-regulated framework, metacognitive strategies are essential to achieve successful learning, but they are resource-consuming and their use might be compromised in demanding contexts such as learning in L2. In Experiment 1, nonbalanced bilinguals read high- and low-cohesion texts in L1 and L2 and self-rated their learning using a judgment of learning (JOL). Then, they answered open-ended questions and responded a customized questionnaire regarding their strategies. In Experiment 2, we introduced two bilingual groups varying in L2 proficiency. Overall, participants could adjust their JOLs and detect the difficulty of the texts correctly in L1 and L2. However, results evidenced some nuances in learning strategies related to L2 proficiency. We discuss these findings within the context of the self-regulated learning.
In response to the COVID-19 pandemic, we rapidly implemented a plasma coordination center, within two months, to support transfusion for two outpatient randomized controlled trials. The center design was based on an investigational drug services model and a Food and Drug Administration-compliant database to manage blood product inventory and trial safety.
Methods:
A core investigational team adapted a cloud-based platform to randomize patient assignments and track inventory distribution of control plasma and high-titer COVID-19 convalescent plasma of different blood groups from 29 donor collection centers directly to blood banks serving 26 transfusion sites.
Results:
We performed 1,351 transfusions in 16 months. The transparency of the digital inventory at each site was critical to facilitate qualification, randomization, and overnight shipments of blood group-compatible plasma for transfusions into trial participants. While inventory challenges were heightened with COVID-19 convalescent plasma, the cloud-based system, and the flexible approach of the plasma coordination center staff across the blood bank network enabled decentralized procurement and distribution of investigational products to maintain inventory thresholds and overcome local supply chain restraints at the sites.
Conclusion:
The rapid creation of a plasma coordination center for outpatient transfusions is infrequent in the academic setting. Distributing more than 3,100 plasma units to blood banks charged with managing investigational inventory across the U.S. in a decentralized manner posed operational and regulatory challenges while providing opportunities for the plasma coordination center to contribute to research of global importance. This program can serve as a template in subsequent public health emergencies.
Malnutrition is common among paediatric heart failure patients, with nutritional rehabilitation critical for survival and optimal health outcomes. Ventricular assist devices have been associated with improved growth, though additional nutritional support may be needed. Here, we report the use of human milk-based fortifiers to avoid severe malnutrition in a neonate supported on a ventricular assist device until transplantation.
This study aims to outline Clostridioides difficile infection (CDI) trends and outcomes in Mexican healthcare facilities during the COVID-19 pandemic.
Design:
Observational study of case series.
Setting:
Sixteen public hospitals and private academic healthcare institutions across eight states in Mexico from January 2016 to December 2022.
Patients:
CDI patients.
Methods:
Demographic, clinical, and laboratory data of CDI patients were obtained from clinical records. Cases were classified as community or healthcare-associated infections, with incidence rates calculated as cases per 10,000 patient days. Risk factors for 30-day all-cause mortality were analyzed by multivariate logistic regression.
Results:
We identified 2,356 CDI cases: 2,118 (90%) were healthcare-associated, and 232 (10%) were community-associated. Common comorbidities included hypertension, diabetes, and cancer. Previous high use of proton-pump inhibitors, steroids, and antibiotics was observed. Recurrent infection occurred in 112 (5%) patients, and 30-day mortality in 371 (16%). Risk factors associated with death were a high Charlson score, prior use of steroids, concomitant use of antibiotics, leukopenia, leukocytosis, elevated serum creatine, hypoalbuminemia, septic shock or abdominal sepsis, and SARS-CoV-2 coinfection. The healthcare-associated CDI incidence remained stable at 4.78 cases per 10,000 patient days during the pre-and pandemic periods. However, the incidence was higher in public hospitals.
Conclusions:
Our study underscores the need for routine epidemiology surveillance and standardized CDI classification protocols in Mexican institutions. Though CDI rates in our country align with those in some European countries, disparities between public and private healthcare sectors emphasize the importance of targeted interventions.
The present study characterized heterogeneity in the cognitive profiles of monolingual and bilingual Latino older adults enrolled in the HABS-HD.
Methods:
A total of 859 cognitively unimpaired older adults completed neuropsychological testing. Raw scores for cognitive tests were converted to z-scores adjusted for age, education, sex, and language of testing. A latent profile analysis (LPA) was conducted for monolingual and bilingual speaker groups. A series of 2–5 class solutions were examined, and the optimal model was selected based on fit indices, posterior probabilities, proportion of sample sizes, and pattern of scores. Identified classes were compared on sociodemographic, psychosocial, and health characteristics.
Results:
For the monolingual group (n = 365), a 3-class solution was optimal; this consisted of a Low Average Memory group with low average verbal memory performances on the SEVLT Total Learning and Delayed Recall trials, as well as an Average Cognition group and a High Average Cognition group. For the bilingual group (n = 494), a 3-class solution was observed to be optimal; this consisted of a Low Average Memory group, with low average verbal memory performances on the learning and delayed recall trials of Logical Memory; a Low Average Executive group, where performance on Trails A and B and Digit Substitution were the lowest; and a High Average Cognition group, where performance was generally in the high average range across most cognitive measures.
Conclusions:
Cognitive class solutions differed across monolingual and bilingual groups and illustrate the need to better understand cognitive variability in linguistically diverse samples of Latino older adults.
Psychotic patients are a vulnerable population from a social and health point of view. The SARS Cov-2 pandemic affected millions of people around the world, however, its effects on psychotic patients in Avilés Spain, have not been analized.
Objectives
The objective of this study was to determine and compare the mortality of patients with psychosis due to SARS Cov-2 in Avilés, Spain with others regions and countries in the European Union. Determine the influence of social condition and antipsychotic treatment on the condition of these patients.
Methods
This is a descriptive, observational study, in which patients diagnosed with psychosis in the period 2020-2021 who contracted SARS Cov-2 infection in Avilés, Spain, were studied to determine those who died from this cause. The influence of social status and antipsychotic medication, as well as sociodemographic factors (age, sex, marital status) were analyzed and compared with other regions and countries of the European Union.
Results
Despite the high mortality rate in patients with psychosis, during the years of the pandemic SARS Cov-2 played an important role given the vulnerability of these patients.
Conclusions
The negative effects and deaths during the COVID-19 pandemic were at the time a major problem for public health worldwide. This study concluded that the morbidity and mortality of psychotic patients who contracted COVID-19 was lower than the rest of the population.
Bipolar I disorder (BD-I) is a chronic and recurrent mood disorder characterized by alternating episodes of depression and mania; it is also associated with substantial morbidity and mortality and with clinically significant functional impairments. While previous studies have used functional magnetic resonance imaging (fMRI) to examine neural abnormalities associated with BD-I, they have yielded mixed findings, perhaps due to differences in sampling and experimental design, including highly variable mood states at the time of scan.
Objectives
The purpose of this study is to advance our understanding of the neural basis of BD-I and mania, as measured by fMRI activation studies, and to inform the development of more effective brain-based diagnostic systems and clinical treatments.
Methods
We conducted a large-scale meta-analysis of whole-brain fMRI activation studies that compared participants with BD-I, assessed during a manic episode, to age-matched healthy controls. Following PRISMA guidelines, we conducted a comprehensive PubMed literature search using two independent coding teams to evaluate primary studies according to pre-established inclusion criteria. We then used multilevel kernel density analysis (MKDA), a well-established, voxel-wise, whole-brain, meta-analytic approach, to quantitatively synthesize all qualifying primary fMRI activation studies of mania. We used ensemble thresholding (p<0.05-0.0001) to minimize cluster size detection bias, and 10,000 Monte Carlo simulations to correct for multiple comparisons.
Results
We found that participants with BD-I (N=2,042), during an active episode of mania and relative to age-matched healthy controls (N=1,764), exhibit a pattern of significantly (p<0.05-0.0001; FWE-corrected) different activation in multiple brain regions of the cerebral cortex and basal ganglia across a variety of experimental tasks.
Conclusions
This study supports the formulation of a robust neural basis for BD-I during manic episodes and advances our understanding of the pattern of abnormal activation in this disorder. These results may inform the development of novel brain-based clinical tools for bipolar disorder such as diagnostic biomarkers, non-invasive brain stimulation, and treatment-matching protocols. Future studies should compare the neural signatures of BD-I to other related disorders to facilitate the development of protocols for differential diagnosis and improve treatment outcomes in patients with BD-I.
Acculturative stress is a key social driver of health impacting the mental health of immigrants and refugees from Latin America, which contributes to inequities experienced by them. While there is a robust scientific literature describing and evaluating evidence-based treatments targeting a range of psychiatric disorders, these treatments often do not primarily target acculturative stress. Thus, the present study examined how psychotherapists ought to treat acculturative stress directly in their clinical practice. Ten therapists were interviewed using a qualitative descriptive approach. Rapid contemporary content analysis was used to describe Latino/Hispanic immigrants’ most common presenting problems, the context in which they provide care for these problems, and the psychotherapeutic approaches currently utilized or considered effective in mitigating acculturative stress. Findings revealed that common mental health conditions that therapists addressed among this population, including depression, anxiety and trauma-related somatization, including the unique context in which therapy was delivered. Additionally, specific strategies for addressing acculturative stress such as the importance of acknowledging this stressor, drawing out immigration journey narratives, and behavioural activation approaches were shared. The results from this study can be used to improve the effectiveness of mental health interventions addressing acculturative stress among immigrant and refugee populations.
Key learning aims
(1) To explore how acculturative stress represents a key driver of mental health for immigrants and refugees from Latin America.
(2) To consider ways that cognitive behavioural therapy (CBT) elements can be applied to treating acculturative stress and mental health problems among immigrants and refugees from Latin America.
(3) To expand upon strategies that can be helpful in rapport-building and establishing trust with patients who are struggling with acculturative stress.
The prevalence of medical illnesses is high among patients with psychiatric disorders. The current study aimed to investigate multi-comorbidity in patients with psychiatric disorders in comparison to the general population. Secondary aims were to investigate factors associated with metabolic syndrome and treatment appropriateness of mental disorders.
Methods
The sample included 54,826 subjects (64.73% females; 34.15% males; 1.11% nonbinary gender) from 40 countries (COMET-G study). The analysis was based on the registration of previous history that could serve as a fair approximation for the lifetime prevalence of various medical conditions.
Results
About 24.5% reported a history of somatic and 26.14% of mental disorders. Mental disorders were by far the most prevalent group of medical conditions. Comorbidity of any somatic with any mental disorder was reported by 8.21%. One-third to almost two-thirds of somatic patients were also suffering from a mental disorder depending on the severity and multicomorbidity. Bipolar and psychotic patients and to a lesser extent depressives, manifested an earlier (15–20 years) manifestation of somatic multicomorbidity, severe disability, and probably earlier death. The overwhelming majority of patients with mental disorders were not receiving treatment or were being treated in a way that was not recommended. Antipsychotics and antidepressants were not related to the development of metabolic syndrome.
Conclusions
The finding that one-third to almost two-thirds of somatic patients also suffered from a mental disorder strongly suggests that psychiatry is the field with the most trans-specialty and interdisciplinary value and application points to the importance of teaching psychiatry and mental health in medical schools and also to the need for more technocratically oriented training of psychiatric residents.
In response to the Omicron surge in early 2022, the HTA Philippines evaluated the acceptability of Filipinos in using self-administered antigen tests (SAAgTs) as part of COVID-19 HTAs in the Philippines.
Methods
Scoping review from literature databases was initially conducted to identify preset codes in the use of SAAgT. Preset codes were used to establish the questions for focus group discussions (FGDs). Semi-structured questionnaires were created through Delphi technique. FGDs with four stakeholder groups (i.e., nine healthcare workers [HCWs], seven representatives of at-risk groups, six economic frontliners, and seven representatives of micro–small–medium-sized enterprises) were conducted.
Results
Discomfort in being a target of stigma and being prescribed an “illness identity” when suspected or confirmed COVID-19-positive, along with lack of confidence to perform self-test, caused hesitancy in self-testing among participants. The need for subsidies for test kits from the government or employers was emphasized to increase its accessibility. Having a designated access point and reporting system for SAAgT was highlighted to avoid nepotism (padrino system attributed to debt of gratitude), inequitable distribution, and lapses in reporting. A participatory approach to education was perceived as crucial to reduce any misconceptions associated with the use of SAAgT.
Conclusions
All FGD groups expressed favorable reviews on the implementation of SAAgT because it can potentially reduce the burden of health facility-administered tests. These findings were considered by the HTA Council in the recommendation of SAAgT as part of the overarching national strategies for the diagnosis and screening of COVID-19.
Pathologic grooming disorders can lead to clinically significant distress and functional impairment. Various psychopharmacological and nonpharmacological treatments have been used to ameliorate the symptoms of these disorders. N-Acetylcysteine (NAC) is a newer modality in the treatment of these disorders and has shown promise in treatment of obsessive-compulsive and related disorders.
Objectives
To determine whether NAC is useful in the treatment of body-focused repetitive behavior disorders.
Methods
A literature review was carried out in PubMed using the descriptors: “body-focused repetitive behaviour disorders” “grooming disorders” AND “N-Acetylcysteine”.
Six results were obtained when using the time limit of 5 years. We selected two of them for their relevance to the PICO question. Subsequently, the search was repeated using the same descriptors and the time limit in the Cochrane Library, Epistemokinos and Tripdatabase, in which no additional results were found.
Results
Overall, thirty-three articles were included in these systematic reviews that we studied, which consisted of 23 case reports, one case series, and seven randomized controlled trials. Dosing of oral NAC ranged from 450 to 3,000 mg per day, and treatment periods lasted from 1 to 8 months. Side effects were uncommon, mild, and usually gastrointestinal in nature, with severe aggression reported in one child. Two randomized controlled trials showed a significant improvement in trichotillomania and excoriation disorder in adults. The other two were performed in pediatric population, showing no statistical difference. Two randomized controlled trials and six case reports studying the effects of NAC in patients suffering from trichotillomania (one performed in adults and the other one in infants) were included. Only the one performed in adults showed improvement when adding NAC to the treatment using the Massachusetts General Hospital, Hairpulling Scale (MGH-HPS). Four case reports and two randomized controlled trials included patients with excoriation disorder showed statistical differences in all of them. Three case reports and one randomized controlled trial in patients with onicotylomania showed a difference that wasn’t consistent after two months of treatment.
Conclusions
There are multiple case reports an several clinical trials supporting both the safety and efficacy of NAC in the treatment of body-focused repetitive behavior disorders. Based on these positive preliminary results and the absence of serious adverse effects, carrying out a therapeutical trial with NAC is a plausible option in the management of this pathology, especially in those in which other therapeutic options have not been effective. Further studies are needed to develop a treatment algorithm and elucidate the difference in the efficacy of NAC between children and adults with this disorder.
Transition between adolescence and adulthood represents the most important challenge for personal development and involves several transformations: physical, psychological and social. It is a complex age bracket, concurring the transition from youth psychiatric units to adult ones, with an increased risk for the appearance of mental disorders and risky behaviours. TRANVIA program, developed in Avilés, provides psychiatric assistance to patients between 15 and 25 years old, diagnosed with a severe psychiatric disorder or with an increased risk of having one.
Objectives
Our objectives are: ensuring clinical continuity assistance, promoting communication among professionals and the empowerment of our patients to improve their functionality and quality of life.
Methods
Descriptive study including patients involved in TRANVIA program from November 2019 to November 2021.
Results
During this two-years period there have been 44 referrals to the program, 11 of them were rejected for failure to comply with diagnostic criteria. In November 2021 there were 33 patients included in the TRANVIA program with an average age of 17 years old (range: 15-22). 70% of them were men and 30% women. All of them had psychiatric assistance from different sources: youth mental health units, neuropediatrics… About 75% of the patients were diagnosed with autistic spectrum disorder and approximately three-quarters of the sample needed pharmacological treatment. Risperidone was the most prescribed drug. We have also developed other assistance alternatives as home-based care, relaxation sessions, social worker interventions and coordination with schools.
Conclusions
TRANVIA program has allowed us to provide continual attention to vulnerable patients that shift from youth psychiatric units to adult ones. Patients that meet inclusion criteria were enrolled independently the type of assistance they have previously received. Accessibility and flexibility were our priority. During the described period there was only one dropout, three patients required psychiatric hospitalization and two others visited the emergency department. There have been no cases of completed suicide.
The Autonomous Sensory Meridian (ASMR) is a static or tingling sensation on the skin that usually starts on the scalp and runs through the back of the neck and upper spine. It has been compared to tactile auditory synesthesia and may overlap with shivering. It is a subjective experience of “low-grade euphoria”, characterized by “a combination of positive feelings and a static tingling sensation on the skin”. It is most commonly triggered by auditory or visual stimuli, and less commonly by intentional attentional control.
Objectives
To determine the effects produced by the perception of ASMR in the population with mental disorders.
Methods
A literature review was carried out in Pubmed using the descriptors: “ASMR” AND “mental”. 7 results are obtained. The results of a time limit of 10 years were filtered, obtaining 6 results and selecting all of them for their relevance to the PICO question. Subsequently, the search was repeated using the same descriptors and time limit in the Cochrane Library and NICE, in which no results were found.
Results
The first result, an RCT of 475 people between the ages of 18 and 54, showed that 80% of the participants answered positively when asked if ASMR has an effect on their mood, while 14% were not sure and 6 % felt ASMR did not alter their mood. When subjected to a mixed ANOVA with factors for time (before, during, immediately after, and 3 h after ASMR) and for depression status (high, medium, or low as defined by the BDI), we found a significant main effect. of time in mood. [p<0.0005]
In one of these studies, the default neural network (the one that works when the brain is relaxed) was analyzed in 11 volunteers in whom ASMR caused them to relax, in contrast to 11 individuals in the control group. At the end of the study, the ASMR volunteers generally showed less functional connectivity than the other volunteers. It also showed “increased connectivity between regions of the occipital, frontal, and temporal cortices,” suggesting that ASMR favors the association of those networks that are activated in the resting state.
Conclusions
With the available evidence it is concluded that ASMR could improve of the affective clinic reflected in the parameters of the Beck depression scale as well as a sense of calm and relaxation and it reduces the heart rate or increases the conductivity of the skin, something that happens when certain emotional states are altered.
Curiosity toward the effects of psychedelic drugs on neural activation has increased due to their potential therapeutic benefits, particularly serotonergic psychedelics that act as 5-HT2A receptor agonists such as LSD, psilocybin, and MDMA. However, the pattern of their effects on neural activity in various brain regions in both clinical and healthy populations is still not well understood, and primary studies addressing this issue have sometimes generated inconsistent results.
Objectives
The present meta-analysis aims to advance our understanding of the most widely used serotonergic psychedelics – LSD, psilocybin, and MDMA – by examining their effects on the functional activation throughout the whole brain among both clinical and healthy participants.
Methods
We conducted this meta-analysis by applying multilevel kernel density analysis (MKDA) with ensemble thresholding to quantitatively combine existing functional magnetic resonance imaging (fMRI) studies that examined whole-brain functional activation of clinical or healthy participants who were administered a serotonergic psychedelic.
Results
Serotonergic psychedelics, including LSD, psilocybin, and MDMA, exhibited significant effects (α=0.05) on neural activation in several regions throughout the cerebral cortex and basal ganglia, including effects that may be common across and unique within each drug.
Conclusions
These observed effects of serotonergic psychedelics on neural activity advance our understanding of the functional neuroanatomy associated with their administration and may inform future studies of both their adverse and therapeutic effects, including emerging clinical applications for the treatment of several psychiatric disorders.
V. bicolor, V. trifolia s. str. and V. rotundifolia are part of a species complex that has recorded medicinal use in the Philippines. We assembled the first chloroplast genome of V. bicolor through next-generation sequencing and compared this to earlier established chloroplast genomes of V. trifolia s. str. and V. rotundifolia to provide additional insights into their genotypic differences. To ensure the continued utility of the research outputs in case of future taxonomic revisions, we characterized the morphology of PBN 2018-674, the reference germplasm utilized to generate the plastome. The complete chloroplast genome sequence of V. bicolor was 154,460 bp long with 131 coding genes comprising 87 mRNA genes, 36 tRNA genes and 8 rRNA genes. Using a separate accession from a different type locality, an identical chloroplast genome was equally established, indicating its conserved nature. When compared to V. trifolia s. str. and V. rotundifolia, slight variations were observed in genome features between these species; however, single nucleotide polymorphisms were exhibited in 13 protein-coding genes that often have a conserved nature. A phylogenetic analysis of the assembled genome, together with 12 other Lamiaceae species, exhibited high bootstrap support (>88%) within the species complex, and associated V. trifolia as the closest relative of V. bicolor. The identified variations in the plastomes can be utilized as markers that could distinguish the three closely related genotypes which can help the Philippine herbal industry provide a more stable source of quality herbal medicines.
The effectiveness of community-based participatory research (CBPR) partnerships to address health inequities is well documented. CBPR integrates knowledge and perspectives of diverse communities throughout the research process, following principles that emphasize trust, power sharing, co-learning, and mutual benefits. However, institutions and funders seldom provide the time and resources needed for the critical stage of equitable partnership formation and development.
Methods:
Since 2011, the Detroit Urban Research Center, collaborating with other entities, has promoted the development of new community–academic research partnerships through two grant programs that combine seed funding with capacity building support from community and academic instructors/mentors experienced in CBPR. Process and outcomes were evaluated using mixed methods.
Results:
From 2011 to 2021, 50 partnerships received grants ranging from $2,500 to $30,000, totaling $605,000. Outcomes included equitable partnership infrastructure and processes, innovative pilot research, translation of findings to interventions and policy change, dissemination to multiple audiences, new proposals and projects, and sustained community–academic research partnerships. All partnerships continued beyond the program; over half secured additional funding.
Conclusions:
Keys to success included participation as community–academic teams, dedicated time for partnership/relationship development, workshops to develop equity-based skills, relationships, and projects, expert community–academic instructor guidance, and connection to additional resources. Findings demonstrate that small amounts of seed funding for newly forming community–academic partnerships, paired with capacity building support, can provide essential time and resources needed to develop diverse, inclusive, equity-focused CBPR partnerships. Building such support into funding initiatives and through academic institutions can enhance impact and sustainability of translational research toward advancing health equity.
The Dasylirion genus is highly represented in the arid and semi-arid regions of Mexico and USA, playing important ecological and economical roles. Inferring the evolutionary patterns of this group will eventually facilitate understanding biological phenomena and outlining conservation and usage strategies. We performed a molecular phylogenetic analysis based on two chloroplast DNA regions: maturase-K gene (matK) and the large subunit of ribulose-1,5-bisphosphate carboxylase gene (rbcL). We constructed a phylogenetic tree by maximum likelihood with GTR as the sequence substitution model and a relaxed clock, inferred diversification patterns by lineage through time and explored the diversification rates of Dasylirion by the Yule model. The study included 11 species of the genus, which represent 50% of all its known species. We used two calibration points to date the tree, one based on fossil records of Acorus gramineus, and the other on the estimated stem age of the Yucca genus. The combined sequences of the two partial genes comprised 1455 bp and 18 polymorphic sites. We estimated an average substitution rate of 0.0005 nucleotide per million years for the concatenated DNA sequences. The molecular dating analysis estimated that the Dasylirion genus appeared more than 5.46 million years ago, with a rate of diversification of 0.0466 net speciation events per million years. The estimated age represents a lower bound, since not all Dasylirion species are included. These findings are consistent with other origin and diversification hypotheses for arid-land Asparagaceae in the Mexican highlands as a result of geomorphological events in North America.