Northern Mexico Research Articles

Another remarkable new species of Dictyanthus (Apocynaceae, Asclepiadoideae, Asclepiadeae, Gonolobinae) with a long stylar head from Mexico

Dictyanthus includes 17 climbing species distributed from northern Mexico to Nicaragua. Mexico is its main center of diversification with 15 endemic species. The genus is known for its conspicuous flowers with high ornamental potential. Dictyanthus species are distinguished by the shape of their corolla (campanulate or rotated), their pattern of color lines or reticulations on the corolla lobes, the size and shape of their corona, and the shape of the stylar head. The present work formally names as a new species, and describes and illustrates the plants with a long and conspicuous stylar head, distinguishing it from the rest of its relatives. The study consisted of field work for two years, as well as a review of herbarium material and literature. The description of the organism was based on in situ morphology, herbarium material and specimens preserved in ethanol. The conservation assessment was based on IUCN criteria. We follow the cohesive species concept as an explanatory hypothesis for the taxa. A dichotomous key and comparative plates are presented for species with stylar head projection. Dictyanthus unicornus differs from other species in the genus by its conspicuously elongated stylar head and the combination of patent corolla lobes and fleshy, spatulate crown lobes protruding from the corolla throat. According to IUCN criteria, this species is considered Endangered. With the present discovery, the genus Dictyanthus reaches 18 described species of which 16 endemic to Mexico.

Bioactive Compounds and Pharmacological Potential of Hojasen (Flourensia cernua): A Mini review

Flourensia cernua, commonly known as hojasen, is a shrub that is widely distributed in northern Mexico and the southern United States. The presence of this shrub indicates the characteristic flora of the Chihuahuan desert and southern Arizona, and it is an endemic plant of the Coahuila region in Mexico. The leaves and flowers of F. cernua are commercially available in Mexican markets for preparing infusions and are used as traditional medicine, mainly for gastrointestinal disorders such as indigestion, diarrhea, stomach pain, and dysentery, among others. Several studies have shown that F. cernua extracts contain bioactive compounds that can act as antioxidants in vitro by stopping free radicals from doing damage. In addition, F. cernua extracts have antifungal activity against phytopathogenic fungi. Additionally, F. cernua extracts have demonstrated antibacterial effects against Mycobacterium tuberculosis. Also, the anti-inflammatory effect of leaf extract at different doses has been studied to see how it affects the production of inflammatory cytokines and nitric oxide (NO) in macrophage cultures. Therefore, identifying its components and pharmacological properties can promote its use as an adjunct or therapeutic candidate in controlling various diseases. With its potential to alleviate gastrointestinal issues, provide antioxidant protection, and inhibit fungi and bacteria, hojasen extract may prove to be a valuable addition to the treatment of many diseases. This minireview aims to expand the existing knowledge about hojasen, a semi-desert shrub that possesses different bioactive compounds belonging to families of interest such as flavonoids, sesquiterpenoids, and coumarins, hoping to arouse the interest of other researchers to further investigate the activities, properties and uses attributed to Flourensia cernua.

Urban Violence, Migration and Alcohol, Tobacco, and Marijuana Use among Transnational Students in Northern Mexico.

This article reports on the findings of a study of the relationship between transnational experiences in the United States (US) and the use of alcohol, tobacco, and marijuana among 7th grade students (n = 1418). The study was guided by a cross-national framework for research on immigrant health and assessed the accumulation of risk factors for transnational adolescents. Data came from a survey conducted in 2017 in Nogales, Mexico. In this study, the last 30-day prevalence of use of alcohol, tobacco, and marijuana among students was 21.7%, 8.3%, and 2.4%, respectively. Most students were born in Nogales (69.6%), while 10.5% were born in the US, 7.5% attended school in the US, and 3.6% engaged in health-related risk behaviors while living in or visiting the US. Students with transnational experiences, such as attending school in the US, reported the highest 30-day prevalence of tobacco (13.3%) and marijuana (9.5%) use. After adjusting for family, school, access to substances and neighborhood violence variables, students who engaged in health-related risk behavior in the US had significantly increased odds of alcohol and marijuana use while later attending school in Mexico. The article discusses the findings from a prevention science perspective and provides implications for policy, practice, and future research on the Mexico-US border region.

From Fresh to Salt Waters: First Reports of the Red Swamp Crayfish Procambarus clarkii (Girard, 1852) in Mediterranean Marine Waters

The red swamp crayfish Procambarus clarkii (Girard, 1852), native to the southern/southeastern United States and northern Mexico, has been introduced in many countries worldwide. The species has a remarkable invasiveness due to its high reproductive rate and ability to tolerate broad ranges of water parameters like salinity. Nevertheless, no consistent observations of P. clarkii have been reported in the marine environment until now. Data demonstrating the presence of the crayfish within marine ecosystems were collected by a personal acquaintance and two volunteers who published photos of the species on Facebook marine biology and fishing groups. The species was identified based on photos taken by these people in the described areas. P. clarkii has been spotted in three different localities, in two of which observations are recurrent. The species can survive miles from the nearest freshwater stream and could potentially colonise marine waters at depths up to 20 m. The multiple observations of P. clarkii collected in our study uncover a persistent presence of the species within some marine areas, rather than its mere sporadic occurrence. Our results highlight the need for further investigation to obtain a comprehensive understanding of the crayfish’s ability to withstand salinity and colonise the marine environment.

Introduction pages, Notulae Scientia Biologicae 15(4), 2023

Notulae Scientia Biologicae (http://www.notulaebiologicae.ro), Issue 4, Volume 15, 2023: The papers published in this issue represent interesting novelties in different topics of life science. Among the exciting research or reviews, we invite readers to find news about: Medicinal potential and health benefits of torch ginger (Etlingera elatior); Phytochemical profile, antioxidant and anti-inflammatory activities of crude latex (Pergularia tomentosa L.) in Algerian Saharan; Extractive optimization of antioxidants and phenolic compounds from Anacyclus pyrethrum; Antimicrobial and mosquito larvicidal activity of iron oxide nanoparticles phytosynthesized from the medicinal plant Andrographis serpyllifolia; Phytochemical characterization, biological screening and corrosion inhibition of mild steel from extracts of Juniperus oxycedrus L.; Supply of essential and nonessential amino acids, proteins, antioxidants, iron and zinc from the main varieties of beans consumed in Mexico and their potential for biofortification; Seed dormancy mechanism and dormancy-breaking methods in wild raspberry (Rubus fraxinifolius Poir.); New insights regarding the taxonomy and phylogeography of Onobrychis montana DC. subsp. transsilvanica (Fabaceae); Estimating dendrometric variables, volume and carbon from stump diameter for Pinus arizonica Engelm. in northern Mexico.

Environmental and geographic low suitability overlapping of geoduck clams in the Pacific Northeast predicted by Ecological Niche Modeling

The known distribution limits of geoduck clams (genus Panopea) remain geographically separated globally. However, in the northeast Pacific, P. generosa is distributed from Alaska to northern Mexico, but approaches, and likely overlaps, the distribution of P. globosa, which is mainly distributed in the Gulf of California. There is incipient evidence that both populations coexist in the central part of the Baja California Peninsula on the Pacific coast. However, knowledge of the biogeographic distribution and environmental conditions for both species is still developing. To address the hypothesis of coexistence in the same geographic space, we developed distribution area models using ecological niche modeling through the maximum entropy algorithm. The algorithm used presence-only records and environmental layers (predictive variables) such as mean surface temperature, mean salinity, mean depth, temperature range, and primary productivity. The results indicate that both species overlap in a narrow portion of the environmental space (Grinnellian ecological niche), which is reflected in a restricted geographic distribution with conditions of low abiotic suitability. Our results contribute to directing new research in the areas of ecology, biogeography, paleontology, and geoduck clam fisheries management.

Response of water yield to silvicultural treatments in a temperate forest in northern Mexico

Forest management modifies tree cover, directly influencing various ecosystem services, such as water regulation. Evapotranspiration, water interception, surface runoff, stemflow, and throughfall are among those processes that depend on tree cover. The objective of this study was to evaluate the changes in water yield, defined as the difference between precipitation and evapotranspiration, after the application of silvicultural treatments in a temperate forest ecosystem in northern Mexico. Fifteen experimental plots were established in which the following treatments were applied: intensive management (clearcutting), semi-intensive management (selection, tree cutting of 59–61% of basal area), conservative management (selection, tree cutting of 29–31% of basal area), and no treatment (control group). Incident precipitation, throughfall, stemflow, net precipitation, interception, and surface runoff were analyzed. Results show that conservative management treatments increase water yield between 2 to 3.6 mm per m-2 ha-1 of tree basal area removed. Water flow distribution, in relation to the incident precipitation, ranged from 72.3 to 91.8% for throughfall, 0.2 to 0.4% for stemflow, 72.7 to 91.8% for net precipitation, 8.19 to 27.42% for interception or evaporation, and 0.54 to 1.93% for surface runoff. The conservative management treatment was the most viable alternative for increasing water yield without compromising timber harvesting and loss of soil due to hydric erosion.

Estimación de la disponibilidad a pagar en dos acuíferos en Baja California, México

This study presents an assessment of the perceptions and willingness-to-pay (WTP) of farmers using groundwater for irrigation in two aquifers in northern Baja California, Mexico. Contingent Valuation (CV) measured their WTP to ensure availability of groundwater in the future. Data from surveys of 70 and 54 farmers in the Maneadero and Guadalupe valleys, respectively, were combined and analyzed using logistic regression. Farmer WTP is influenced by variables reflecting “present water scarcity for agricultural use”, “education and family income levels”, “partial use of wastewater for irrigation”, “water quality”, and “payment amount”. A WTP estimate of $US 0.13/m3 suggests that the environmental cost of depleting aquifers over a 20-year span could reach $US 17.4-24.9 million for the Guadalupe aquifer and $US 20.50 million for the Maneadero aquifer. This information could serve as a starting point to help decision makers in northern Mexico design more environmentally sustainable pricing policies, including investing revenues in long-term aquifer restoration.

Ecological Attributes of the Shrubby Community of Sotol (Dasylirion leiophyllum) in the Chihuahuan Desert, Mexico

Sotol (Dasylirion leiophyllum) is a shrubby species that grows in the Chihuahuan Desert. Sotol plants are commonly used to produce an alcoholic beverage, also known as “sotol”. A study was carried out to assess the composition and structure of shrubby communities where sotol inhabits in northern Mexico. The importance value index (IVI), diversity indexes, and structural attributes of the sotol community were estimated. Furthermore, a principal component and a cluster analysis were conducted in order to identify possible associations of species along the sotol distribution area. A total of 10,273 plants belonging to 17 families and 46 species were recorded, where the Agave lechuguilla and Tiquilia greggi were the most abundant species. Higher abundances of sotol and higher diversity indexes were observed in hillside areas and eastern aspects. The multivariate analyses revealed five shrubby groups in the distribution area of sotol, which grows in valleys, hillsides, and also on the top of mountains. The main communities found where sotol grows are rosetophyllous, microphyllous, and mesquite communities, and also, in higher altitudes, sotol is associated with oak species. This information is not only useful for a better species knowledge, but also for the protection of shrubby communities where Dasylirion leiophyllum inhabits.

Willingness toward post-mortem body donation to science at a Mexican university: an exploratory survey

BackgroundVoluntary post-mortem donation to science (PDS) is the most appropriate source for body dissection in medical education and training, and highly useful for biomedical research. In Mexico, unclaimed bodies are no longer a legal source, but PDS is legally possible, although scarcely facilitated, and mostly ignored by the general population. Therefore, we aimed to evaluate the attitude and willingness for PDS and to identify a sociodemographic profile of people with willingness toward PDS.MethodsA validated on-line survey was distributed by the convenience method via the social networks of a Catholicism-inspired, private university in northern Mexico. Frequency analyses of all variables and coded free comments were complemented with association studies.ResultsAlthough the responder cohort (n = 143) was too small and biased to be representative of the university community (n = 13,500), willingness to post-mortem organ donation was 90.7% and to PDS 70.7%. In this cohort, PDS willingness had the strongest association with mature age (> 40 years old; P, 0.0008). Among young adults, willingness to PDS was the lowest among volunteers from technical and business schools and the highest among those from the social sciences (P, 0.009). Respondents from the social sciences were also the most consistent between attitude and behavior with respect to organ donation. A free comment option revealed respondents were interested in the unusual taboo topic.ConclusionsA small, but sufficiently large proportion expressed willingness toward PDS. In our university cohort, which was biased in higher education and altruism, mature age and social interest were associated with PDS willingness.

Esophagic atresia type and its association with heart malformations in a Northern Mexico hospital

Esophagic atresia type and its association with heart malformations in a Northern Mexico hospital

Estimating dendrometric variables, volume and carbon from stump diameter for Pinus arizonica Engelm. in northern Mexico

It is noteworthy that in the last decade, there has been an increase in the number of studies predicting normal diameter, total height, and stem volume based on stump dimensions. Therefore, the objectives were: a) to determine the mathematical model that best estimates normal diameter, total height, stem volume, and captured carbon as a function of stump diameter for Pinus arizonica Engelm. in northern Mexico; and b) to generate mathematical models through data processing in the Microsoft Excel program. Using a targeted sampling design, we selected 264 Pinus arizonica Engelm. trees to generate the database. The development of prediction models for normal diameter, total height, total tree volume, and captured carbon as a function of stump diameter was carried out using the Microsoft Excel database management package. The fit's adequacy was analyzed based on residuals and statistics such as the root mean square error, the adjusted coefficient of determination, and the coefficient of variation. Model fits indicate a linear trend for the normal diameter variable, while for total height, the model turned out to be logarithmic. As for total tree volume and captured carbon, the relationship is exponential in relation to stump diameter. The R2adj fits were highly reliable for estimating normal diameter, total tree volume, and captured carbon, with values exceeding 95%. The development of prediction models using Microsoft Excel is viable according to the results presented here. The tested techniques can be replicated by forestry technicians, environmental inspectors, and forest landowners who do not have specialized knowledge in the generation prediction models.

Bacterial communities of the psyllid pest Bactericera cockerelli (Hemiptera: Triozidae) Central haplotype of tomato crops cultivated at different locations of Mexico.

The psyllid, Bactericera cockerelli, is an insect vector of 'Candidatus Liberibacter' causing "Zebra chip" disease that affects potato and other Solanaceae crops worldwide. In the present study, we analyzed the bacterial communities associated with the insect vector Bactericera cockerelli central haplotype of tomato crop fields in four regions from Mexico. PCR was used to amplify the mitochondrial cytochrome oxidase I gene (mtCOI) and then analyze the single nucleotide polymorphisms (SNP) and phylogenetic analysis for haplotype identification of the isolated B. cockerelli. Moreover, we carried out the microbial diversity analysis of several B. cockerelli collected from four regions of Mexico through the NGS sequencing of 16S rRNA V3 region. Finally, Wolbachia was detected by the wsp gene PCR amplification, which is the B. cockerelli facultative symbiont. Also we were able to confirm the relationship with several Wolbachia strains by phylogenetic analysis. Our results pointed that B. cockerelli collected in the four locations from Mexico (Central Mexico: Queretaro, and Northern Mexico: Sinaloa, Coahuila, and Nuevo Leon) were identified, such as the central haplotype. Analyses of the parameters of the composition, relative abundance, and diversity (Shannon index: 1.328 ± 0.472; Simpson index 0.582 ± 0.167), showing a notably relatively few microbial species in B. cockerelli. Analyses identified various facultative symbionts, particularly the Wolbachia (Rickettsiales: Anaplasmataceae) with a relative abundance higher. In contrast, the genera of Sodalis and 'Candidatus Carsonella' (Gammaproteobacteria: Oceanospirillales: Halomonadaceae) were identified with a relatively low abundance. On the other hand, the relative abundance for the genus 'Candidatus Liberibacter' was higher only for some of the locations analyzed. PCR amplification of a fragment of the gene encoding a surface protein (wsp) of Wolbachia and phylogenetic analysis corroborated the presence of this bacterium in the central haplotype. Beta-diversity analysis revealed that the presence of the genus 'Candidatus Liberibacter' influences the microbiota structure of this psyllid species. Our data support that the members with the highest representation in microbial community of B. cockerelli central haplotype, comprise their obligate symbiont, Carsonella, and facultative symbionts. We also found evidence that among the factors analyzed, the presence of the plant pathogen affects the structure and composition of the bacterial community associated with B. cockerelli.

Experience with OK-432 in lymphatic vascular malformations in a hospital from northern Mexico

Experience with OK-432 in lymphatic vascular malformations in a hospital from northern Mexico

Risk assessment for the distribution and levels of fluoride and nitrate in groundwater in a semi-arid area of northern Mexico

This study assessed groundwater quality and associated risks in a semi-arid region located in a city in the Northern zone of Mexico. To conduct this study, we collected 92 groundwater samples and analyzed 14 physicochemical parameters across 18 sectors. Only fluoride (F−) and nitrate (NO3–N) exceeded Mexican regulations and WHO guidelines for drinking water. Approximately 65 % of samples surpassed the 1.5 mg/L permissible limit for F−, with the highest recorded concentration reaching 3.60 mg/L in two sectors among the 18 studied, 34 % of samples exhibited NO3−-N concentrations in the 10.64–17.27 mg/L range across three sectors, surpassing permissible levels. Pearson Correlation Analysis revealed strong positive correlations with HCO3−, EC, Mg2+, Ca2+, NO3−, Cl−, SO42−, and Na+. Moderate correlations existed for the total hardness, alkalinity, Cl−, NO3−, SO42−, Na+, Mg2+, and EC. K+ showed weak correlations. PIG values indicated significant pollution of F− in all of 18 sectors (PIG <1). HQ for F− exceeded tolerable levels in 14 adult and 16 child sectors, posing an intolerable risk. Nitrate's HQ was below <1 for all age groups, suggesting non-carcinogenic effects. THI indicated high F− and NO3−-N exposure risks for children in the study area. It is recommended to implement effective water treatment technologies, such as reverse osmosis or adsorptive materials, in those sectors reported as a potential risk to human health to ensure access to safe drinking water.

Determinants of genetic diversity in Neotropical salamanders (Plethodontidae: Bolitoglossini).

Genetic diversity is the raw material of evolution, yet the reasons why it varies among species remain poorly understood. While studies at deeper phylogenetic scales point to the influence of life history traits on genetic diversity, it appears to be more affected by population size but less predictable at shallower scales. We used proxies for population size, mutation rate, direct selection, and linked selection to test factors affecting genetic diversity within a diverse assemblage of Neotropical salamanders, which vary widely for these traits. We estimated genetic diversity of noncoding loci using ddRADseq and coding loci using RNAseq for an assemblage of Neotropical salamanders distributed from northern Mexico to Costa Rica. Using ddRADseq loci, we found no significant association with genetic diversity, while for RNAseq data we found that environmental heterogeneity and proxies of population size predict a substantial portion of the variance in genetic diversity across species. Our results indicate that diversity of coding loci may be more predictable than that of noncoding loci, which appears to be mostly unpredictable at shallower phylogenetic scales. Our results suggest that coding loci may be more appropriate for genetic diversity estimates used in conservation planning because of the lack of any association between the variables we used and genetic diversity of noncoding loci.

Differential diagnosis of lophomaniasis in patients with COVID-19 in northern Mexico: a case report

Pulmonary lophomoniasis is a rare infection produced by a multiflagellated and anaerobic pyriform or oval protozoan belonging to the family of Lophomonadidae. The study aimed learn the differential diagnosis of lophomoniasis in patients with COVID-19 in northern Mexico. Clinical case of a 37-years-old male patient diagnosed with pneumonia, respiratory syndrome, hemoptysis, and fever, which suggested pulmonary tuberculosis. Bronchial lavage was performed, and laboratory tests were requested, an RT-PCR test to search for SARS-CoV-2, which was positive. The results for TB and KOH for fungi were negative. In addition to the protocol, a fresh examination was performed by placing a drop from the sample on a glass slide and observing it with a 10X objective, then 40X searching for clinically structural elements. As a result, multiflagellated cellular elements in the continuous movement were observed that morphologically correspond to the genus Lophomonas spp concluding the bacteriological protocol of bronchial secretions should consider fresh examination to search for trophozoites of Lophomonas spp. Medical and laboratory personnel are unaware of the protozoa Lophomonas spp, since the fresh examination in the analysis protocol is not considered. This paper reports the first case of Lophomonas infection in a patient caused by chronic lung disease.

Evaluation of forest cover loss in properties in the Sierra Madre Occidental, State of Durango, Mexico, certified by the Forest Stewardship Council

Currently, most of the world's forests are governed by policies and regulations that contribute to sustainable forest management. The Forest Stewardship Council (FSC), a voluntary, non-governmental mechanism, proposes a market-based international certification scheme whose mission is to promote environmentally appropriate, socially beneficial and economically viable forest management. Despite the broad scope of the Principles and Criteria of this scheme, there is limited empirical evidence and a lack of rigorous evaluation in relation to the real impact on forest ecosystems. In order to generate evidence to contribute to the discussion, 42 properties (covering a total area of 1.1 Mill. ha) in northern Mexico, with and without FSC certification, were identified and evaluated in the period between 1986 and 2012. The results showed that there were no statistically significant differences (p = 0.14) in forest cover loss between certified and non-certified properties for the period before the properties joined this scheme. Similarly, for the nine-year period after certification, there were no significant differences (p = 0.23) between the two groups. This indicates that the certification scheme has not resulted in significant additional reductions in forest cover loss in certified forest areas. It is therefore important to review the standards imposed and the evaluation methods used in the scheme, in order to identify the real environmental impacts on forest resources and, if necessary, to implement rigorous and reliable methodologies, such as remote sensing tools, to continuously analyze the forest resource in the long term.

Intussusception of the jejuno-jejunal anastomosis in a patient with Roux-en-Y gastric bypass

Intussusception is a rare complication in postoperative patients undergoing Roux-en-Y gastric bypass (RYGB), with an incidence of 0.64%. The clinical presentation usually involves severe abdominal pain, accompanied by nausea and vomiting. The diagnostic approach using imaging studies involves computed tomography, revealing the radiological "target" sign. The treatment is surgical, with the lowest recurrence rate (12.5%) observed in the resection and anastomosis of the intussuscepted segment. The objective is to present the case of intussusception at the jejuno-jejunal anastomosis in a postoperative RYGB patient, along with its therapeutic approach, in a hospital in northern Mexico.

POTENTIAL SHARED DISEASE RISK AMONG DOGS AND COYOTES (CANIS LATRANS) EXEMPLIFIED BY THE ECOLOGY OF RICKETTSIOSIS IN A ROCKY MOUNTAIN SPOTTED FEVER-EPIDEMIC REGION IN NORTHERN MEXICO.

Rocky Mountain spotted fever (RMSF), caused by the bacterium Rickettsia rickettsii, is a re-emerging tick-borne zoonosis in North America, with hundreds of human fatalities in multiple outbreaks in northern Mexico and the southwestern US in the past few decades. Free-roaming dogs are key because they are reservoirs for the pathogen and the main hosts of the brown dog tick (Rhipicephalus sanguineus), which vectors RMSF in this region. Because coyotes (Canis latrans) can be infected with R. rickettsii and infested with Rh. sanguineus, we hypothesized that space sharing among dogs and coyotes could enhance disease risks. In summer 2021, we captured and sampled 11 coyotes at two sites in Baja California, Mexico, near population centers with human cases of RMSF, and fitted seven individuals with GPS logging collars. We also tested tissue samples, sera, and ectoparasites for DNA of R. rickettsii with PCR and used serology to detect antibodies to R. rickettsii. Finally, we deployed an array of cameras to document dog-coyote interactions. Mean home range size was 40.37 km2. Both GPS and camera data showed considerable home range overlap both between individual coyotes and between coyotes and dogs. Coyotes were active in areas where dogs occur including the domestic interface surrounding human settlements. Although none of our samples were positive for R. rickettsii on PCR, 72.7% (8/11) of the samples were seropositive with titers ≥64. Our data confirm shared space use and risk of shared parasites and disease between coyotes and dogs.