Recapitulation of human pathophysiology and identification of forensic biomarkers in a translational model of chlorine inhalation injury.

Chlorine gas (Cl2) has been repeatedly used as a chemical weapon, first in World War I and most recently in Syria. Life-threatening Cl2 exposures frequently occur in domestic and occupational environments, and in transportation accidents. Modeling the human etiology of Cl2-induced acute lung injury (ALI), forensic biomarkers, and targeted countermeasures development have been hampered by inadequate large animal models. The objective of this study was to develop a translational model of Cl2-induced ALI in swine to understand toxico-pathophysiology and evaluate whether it is suitable for screening potential medical countermeasures and to identify biomarkers useful for forensic analysis. Specific pathogen-free Yorkshire swine (30-40 kg) of either sex were exposed to Cl2 (≤240 ppm for 1 h) or filtered air under anesthesia and controlled mechanical ventilation. Exposure to Cl2 resulted in severe hypoxia and hypoxemia, increased airway resistance and peak inspiratory pressure, and decreased dynamic lung compliance. Cl2 exposure resulted in increased total leucocyte and neutrophil counts in bronchoalveolar lavage fluid, vascular leakage, and pulmonary edema compared with the air-exposed group. The model recapitulated all three key histopathological features of human ALI, such as neutrophilic alveolitis, deposition of hyaline membranes, and formation of microthrombi. Free and lipid-bound 2-chlorofatty acids and chlorotyrosine-modified proteins (3-chloro-l-tyrosine and 3,5-dichloro-l-tyrosine) were detected in plasma and lung tissue after Cl2 exposure. In this study, we developed a translational swine model that recapitulates key features of human Cl2 inhalation injury and is suitable for testing medical countermeasures, and validated chlorinated fatty acids and protein adducts as biomarkers of Cl2 inhalation.NEW & NOTEWORTHY We established a swine model of chlorine gas-induced acute lung injury that exhibits several features of human acute lung injury and is suitable for screening potential medical countermeasures. We validated chlorinated fatty acids and protein adducts in plasma and lung samples as forensic biomarkers of chlorine inhalation.

Dynamic optical coherence tomography of chronic venous ulcers.

BACKGROUND: Chronic ulcers, especially venous leg ulcers, are a major burden on the healthcare system. To date there are only few non-invasive established procedures for evaluation of blood perfusion in wounds. Dynamic optical coherence tomography (D-OCT) provides images of the skin's superficial vascularisation. OBJECTIVES: This study aims to investigate if and how the D-OCT measurement of chronic wounds can provide new information about the vascularisation during the healing process. METHODS: We examined 16 venous ulcers over 16 weeks and evaluated the vessel morphology and density using D-OCT at the wound bed, borders, two centimetres adjacent to the wound und at non-ulcerated skin on the contralateral leg. RESULTS: In D-OCT scans clumps were unique and the most common vessel type in the wound area of venous ulcers, whereas lines and serpiginous vessels were the most common in non-ulcerated skin. At the wound border mottle and cluster patterns occurred more frequently. Healthy skin showed a significant increase of mesh pattern. Vessel density significantly increased at the wound area compared to non-ulcerated skin. During the healing process the wound border showed the most vascular changes while only an increase in curves was observed in the wound centre. Non-healing wounds had fewer dots and blobs at the borders, fewer dots, coils, clumps, lines and serpiginous vessels at the centre and fewer dots in adjacent skin. Temperature analysis showed higher temperatures in non-ulcerated skin, followed by the wound margin and centre. Non-healing wounds showed the lowest temperatures in the wound centre. CONCLUSIONS: These results highlight the non-invasive use of D-OCT for the examination and monitoring of wound healing in chronic venous ulcers. D-OCT imaging of blood vessels may offer the potential to detect disorders of wound healing at an early stage, differentiate ulcers of different genesis and to tailor more individualized, patient-oriented therapy.

On the mechanism of visible-light sensitized photosulfoxidation of toluidine blue O.

We report on the formation of toluidine blue O (TBO) sulfoxide by a self-sensitized photooxidation of TBO. Here, the photosulfoxidation process was studied by mass spectrometry (MS) and discussed in the context of photodemethylation processes which both contribute to TBO consumption over time. Analysis of solvent effects with D2O, H2O, and CH3CN along with product yields and MS fragmentation patterns provided mechanistic insight into TBO sulfoxide's formation. The formation of TBO sulfoxide is minor and detectable up to 12% after irradiation of 3 h. The photosulfoxidation process is dependent on oxygen wherein instead of a type II (singlet oxygen, 1O2) reaction, a type I reaction involving TBO to reach the TBO sulfoxide is consistent with the results. Density functional theory results point to the formation of the TBO sulfoxide by the oxidation of TBO via transiently formed peroxyl radical or thiadioxirane intermediates. We discover that the TBO photosulfoxidation arises competitively with TBO photodemethylation with the latter leading to formaldehyde formation.

Pilot Study on the Relationship between Malnutrition and Grip Strength with Prognosis in Diabetic Foot.

Sarcopenia and malnutrition have been associated in the elderly population with a poor prognosis in wound healing and with other adverse events, such as institutionalization or functional impairment. However, it is not known how these factors influence the prognosis of diabetic foot in the elderly. To answer this question, a prospective observational study of 45 patients over 65 years of age admitted with diagnoses of diabetic foot in a tertiary hospital has been conducted. All patients were assessed at admission and at 3 months after returning home to determine quality of life, pain, mobility and healing, overall hospital stay in relation to the presence of malnutrition (measured by BMI, CIPA scale and analytical parameters at admission of serum proteins and albumin), and sarcopenia measured by grip force, among other geriatric syndromes. The results found a relationship between altered sarcopenia and more pain and poorer quality of life, and altered BMI was related to a lower cure rate and worse mobility at follow-up. This study seems to indicate that, in the elderly population with diabetic foot, malnutrition and sarcopenia should be managed at the same time as the treatment of the diabetic foot itself.

A coalition-driven examination of organization capacity to address food insecurity in Greater Houston: a qualitative research study.

Background: Economic and social hardships have worsened food insecurity, particularly among low income and racial-ethnic minority groups. Given the core goal of the 150+ member Houston Health Equity Collective (HEC) to reduce food insecurity by 5% in 2025, we explored member organizations' capacity and challenges faced in screening and responding to food insecurity through care coordination efforts. Methods: A twice-administered Qualtrics XM survey (Provo, Utah) with 76 organizations, followed by five focus groups with 22 of these organizations, explored reach and response efforts to food insecurity. Qualitative assessments lasted between 0.5 to 1.5 h, were audio-recorded, cleaned, coded, and thematically analyzed using NVivo, version 11 (Burlington, Massachusetts). The qualitative study was guided by a general inductive approach. In total, over 6 h of audiovisual recording were extracted, and over 100 pages of text exported to NVivo for data analysis. The research team read and coded transcripts independently using the codebook, and met routinely to discuss and resolve codes -resulting in numerous revisions to the codebook. Coding structure was discussed at multiple meetings and differences were addressed through consensus. Predominant qualitative themes impacting food insecurity screening were "stigma and cultural-related barriers", "clinic capacity and attitudes", "need to focus on upstream influences of food insecurity and SDOH needs", "impact of COVID-19", and "need for HEC system responses". Main recommendations to enhance screening and reach included improving staff culture, enhancing cultural sensitivity across organizational practices, and using shared technology to coordinate care. Respondents stated that the HEC can drive these recommendations through networking opportunities, use of shared resource directory, and placing focus on upstream factors. Conclusions: Recommendations to target food insecurity must focus on organizational staff responsiveness and sensitivity to patients' needs. Of equal importance is the need for increased attention to the upstream influencers and integration of systems-level interventions to holistically target the barriers impacting food insecurity.

Design and Content Validation using Expert Opinions of an Instrument Assessing the Lifestyle of Adults: The 'PONTE A 100' Questionnaire.

Lifestyle, a major determinant of health status, comprises a number of habits and behaviours that form a part of daily life. People with healthy lifestyles have a better quality of life, suffer less disease, and have a longer life expectancy. This work reports the design and content validation of a questionnaire-the 'PONTE A 100' questionnaire-assessing the lifestyle of adults. This collects information across five dimensions-'Eating Habits', 'Physical Activity', 'Smoking and use of Alcohol and other Drugs', 'Emotional Wellbeing', and 'Safety and Non-intentional Injuries'-via the answering of a total 33 items. Psychometric validation of the instrument's content was obtained via expert opinions. This was performed by two rounds of assessment and involved 34 experts representing different health science disciplines (mean experience, 27.4 ± 9.4 years). At the end of each round, adjustments were made according to their recommendations. Agreement between the experts was examined using the Aiken V test. A final V value of 0.95 (95% CI, 0.90-1.00) was obtained for the questionnaire as a whole, highlighting the validity of its content. The questionnaire would therefore appear to be an appropriate instrument for assessing the lifestyle of adults.

Entomopathogens infecting brown marmorated stink bugs before, during, and after overwintering.

The microsporidian, Nosema maddoxi Becnel, Solter, Hajek, Huang, Sanscrainte & Estep, infects brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), populations in North America and Asia and causes decreased fitness in infected insects. This host overwinters as adults, often in aggregations in sheltered locations, and variable levels of mortality occur over the winter. We investigated pathogen prevalence in H. halys adults before, during, and after overwintering. Population level studies resulted in detection of N. maddoxi in H. halys in 6 new US states, but no difference in levels of infection by N. maddoxi in autumn versus the following spring. Halyomorpha halys that self-aggregated for overwintering in shelters deployed in the field were maintained under simulated winter conditions (4°C) for 5 months during the 2021-2022 winter and early spring, resulting in 34.6 ± 4.8% mortality. Over the 2020-2021 and 2021-2022 winters, 13.4 ± 3.5% of surviving H. halys in shelters were infected with N. maddoxi, while N. maddoxi infections were found in 33.4 ± 10.8% of moribund and dead H. halys that accumulated in shelters. A second pathogen, Colletotrichum fioriniae Marcelino & Gouli, not previously reported from H. halys, was found among 46.7 ± 7.8% of the H. halys that died while overwintering, but levels of infection decreased after overwintering. These 2 pathogens occurred as co-infections in 11.1 ± 5.9% of the fungal-infected insects that died while overwintering. Increasing levels of N. maddoxi infection caused epizootics among H. halys reared in greenhouse cages after overwintering.

First report of Colletotrichum fioriniae infections in brown marmorated stink bugs, Halyomorpha halys.

An epizootic caused by fungal pathogens occurred among Halyomorpha halys, brown marmorated stink bugs, while they were overwintering, with infections also occurring after overwintering. We report that one of the two pathogens responsible was Colletotrichum fioriniae (Marcelino & Gouli) Pennycook; a species well known as a plant pathogen and endophyte and which has only previously been reported naturally infecting elongate hemlock scales, Fiorinia externa. To prove pathogenicity, H. halys adults challenged with conidia died from infections and the fungus subsequently produced conidia externally on cadavers.

Enhancing the utilization of healthy living interventions among cancer survivors in historically underserved populations and communities.

PURPOSE: This study aimed to describe the clinical characteristics and wellness programming preferences of cancer survivors from Acres Homes, a historically Black neighborhood in Houston, Texas, with areas of persistent poverty. The goal of this study was to identify opportunities to increase cancer survivor utilization of healthy eating and active living interventions aligned to cancer center community outreach and engagement efforts. METHODS: This multiple methods study included a retrospective review of electronic health record data (n = 413) and qualitative interviews with cancer survivors (n = 31) immediately preceding initiation of healthy eating, active living programming in Acres Homes. RESULTS: This study found Acres Homes survivors have high rates of co-occurrent cardiometabolic disease including obesity (45.0%), diabetes (30.8%), and other related risk factors as well as treatment-related symptoms. Four major concepts emerged from interviews: (1) Factors that influence survivors' ability to eat well and exercise, (2) Current usage of community resources, (3) Interest in relevant programming, and (4) Specific programming preferences. Opportunities for current and future health promotion programming for cancer survivors were explored. CONCLUSION: Strategically tailoring community resources for cancer survivors can provide a more robust network of support to promote healthy eating and active living in this population. This work informed community implementation of evidence-based health interventions in Acres Homes and may support future projects aiming to enhance community-led cancer prevention efforts in historically underserved communities.

T-Toxin Virulence Genes: Unconnected Dots in a Sea of Repeats.

In 1970, the Southern Corn Leaf Blight epidemic ravaged U.S. fields to great economic loss. The outbreak was caused by never-before-seen, supervirulent, Race T of the fungus Cochliobolus heterostrophus. The functional difference between Race T and O, the previously known, far less aggressive strain, is production of T-toxin, a host-selective polyketide. Supervirulence is associated with ~1 Mb of Race T-specific DNA; only a fraction encodes T-toxin biosynthetic genes (Tox1). Tox1 is genetically and physically complex, with unlinked loci (Tox1A, Tox1B) genetically inseparable from breakpoints of a Race O reciprocal translocation that generated hybrid Race T chromosomes. Previously, we identified 10 genes for T-toxin biosynthesis. Unfortunately, high-depth, short-read sequencing placed these genes on four small, unconnected scaffolds surrounded by repeated A+T rich sequence, concealing context. To sort out Tox1 topology and pinpoint the hypothetical Race O translocation breakpoints corresponding to Race T-specific insertions, we undertook PacBio long-read sequencing which revealed Tox1 gene arrangement and the breakpoints. Six Tox1A genes are arranged as three small islands in a Race T-specific sea (~634 kb) of repeats. Four Tox1B genes are linked, on a large loop of Race T-specific DNA (~210 kb). The race O breakpoints are short sequences of race O-specific DNA; corresponding positions in race T are large insertions of race T-specific, A+T rich DNA, often with similarity to transposable (predominantly Gypsy) elements. Nearby, are 'Voyager Starship' elements and DUF proteins. These elements may have facilitated Tox1 integration into progenitor Race O and promoted large scale recombination resulting in race T. IMPORTANCE In 1970 a corn disease epidemic ravaged fields in the United States to great economic loss. The outbreak was caused by a never-before seen, supervirulent strain of the fungal pathogen Cochliobolus heterostrophus. This was a plant disease epidemic, however, the current COVID-19 pandemic of humans is a stark reminder that novel, highly virulent, pathogens evolve with devastating consequences, no matter what the host-animal, plant, or other organism. Long read DNA sequencing technology allowed in depth structural comparisons between the sole, previously known, much less aggressive, version of the pathogen and the supervirulent version and revealed, in meticulous detail, the structure of the unique virulence-causing DNA. These data are foundational for future analysis of mechanisms of DNA acquisition from a foreign source.

The Prevalence and Perceived Utility of Mobile Health Technology Among Recently Incarcerated Homeless Adults.

Mobile technologies can deliver physical and mental health services for recently incarcerated homeless adults (RIHAs). The purpose of this study was to examine the prevalence and perceived utility of mobile technology to support health behavior change among RIHAs. Participants (n = 324) from an ongoing clinical trial at a homeless shelter in Texas were included in the current descriptive cross-sectional analyses. Over one fourth (28.4%) of participants had an active cell phone. Nearly 90 percent (88.6%) of participants reported at least weekly use of the internet, 77 percent used email (77.2%), and more than half used Facebook (55.2%). Although most participants (82.8%) believed that smartphone applications (apps) could help change their behavior, only a quarter (25.1%) had used an app for this purpose. These findings highlight the potential for smartphone-based intervention technologies, and future studies should examine whether smartphone apps that address mental health and health behaviors are feasible among RIHAs.

Copper starvation induces antimicrobial isocyanide integrated into two distinct biosynthetic pathways in fungi.

The genomes of many filamentous fungi, such as Aspergillus spp., include diverse biosynthetic gene clusters of unknown function. We previously showed that low copper levels upregulate a gene cluster that includes crmA, encoding a putative isocyanide synthase. Here we show, using untargeted comparative metabolomics, that CrmA generates a valine-derived isocyanide that contributes to two distinct biosynthetic pathways under copper-limiting conditions. Reaction of the isocyanide with an ergot alkaloid precursor results in carbon-carbon bond formation analogous to Strecker amino-acid synthesis, producing a group of alkaloids we term fumivalines. In addition, valine isocyanide contributes to biosynthesis of a family of acylated sugar alcohols, the fumicicolins, which are related to brassicicolin A, a known isocyanide from Alternaria brassicicola. CrmA homologs are found in a wide range of pathogenic and non-pathogenic fungi, some of which produce fumicicolin and fumivaline. Extracts from A. fumigatus wild type (but not crmA-deleted strains), grown under copper starvation, inhibit growth of diverse bacteria and fungi, and synthetic valine isocyanide shows antibacterial activity. CrmA thus contributes to two biosynthetic pathways downstream of trace-metal sensing.

Does substrate matter in the deep sea? A comparison of bone, wood, and carbonate rock colonizers.

Continental margins host methane seeps, animal falls and wood falls, with chemosynthetic communities that may share or exchange species. The goal of this study was to examine the existence and nature of linkages among chemosynthesis-based ecosystems by deploying organic fall mimics (bone and wood) alongside defaunated carbonate rocks within high and lesser levels of seepage activity for 7.4 years. We compared community composition, density, and trophic structure of invertebrates on these hard substrates at active methane seepage and transition (less seepage) sites at Mound 12 at ~1,000 m depth, a methane seep off the Pacific coast of Costa Rica. At transition sites, the community composition on wood and bone was characteristic of natural wood- and whale-fall community composition, which rely on decay of the organic substrates. However, at active sites, seepage activity modified the relationship between fauna and substrate, seepage activity had a stronger effect in defining and homogenizing these communities and they depend less on organic decay. In contrast to community structure, macrofaunal trophic niche overlap between substrates, based on standard ellipse areas, was greater at transition sites than at active sites, except between rock and wood. Our observations suggest that whale- and wood-fall substrates can function as stepping stones for seep fauna even at later successional stages, providing hard substrate for attachment and chemosynthetic food.

Technological Proficiencies, Engagement, and Practical Considerations for mHealth Programs at an Urban Safety-Net Hospital Emergency Departments: Data Analysis.

BACKGROUND: Safety-net emergency departments often serve as the primary entry point for medical care for low income predominantly minority patient populations. Herein, we sought to provide insight into the feasibility, technological proficiencies, engagement characteristics, and practical considerations for a mHealth intervention at a safety-net emergency department. OBJECTIVE: We aimed to analyze patient technological proficiency to understand the feasibility of and draw practical considerations for mobile phone technology (mHealth) solutions for patients with chronic disease served by safety-net emergency departments. METHODS: We analyzed data from a previous diabetes randomized clinical mHealth trial for a diabetes social support intervention. Patients from a safety-net emergency department with preexisting diabetes who used SMS text messages, owned a mobile phone, and with hemoglobin A1c levels >8.5% were enrolled. A text message-based mHealth program to improve disease self-management was provided to all patients. Supporters of patients were randomized to receive a mailed copy or mHealth-based curriculum designed to improve diabetes support. Among enrolled patients, we surveyed mobile technological capacity and frequency of use. We performed latent class analysis to identify classes of patients by level of technological proficiency and compared demographic characteristics between the latent classes to identify demographic subgroups that may require more training or tailoring of the mHealth approach. Study engagement between classes was assessed by comparing the mean number of text messages exchanged, loss to follow-up, and early termination. RESULTS: Of 1876 patients who were approached, 44.2% (n=829) of patients had a stable mobile phone and were able to use text messages. Among them 166 met the trial inclusion and enrolled, 90% (149/166) of the cohort were ethnically diverse. Significant variance was found in technology capacity and frequency of use. Our latent class analysis classified 75% (124/166) of patients as highly technologically proficient and 25% (42/166) patients as minimally technologically proficient. Age (P<.001) and level of education (P<.001) were associated with class membership. Highly technologically proficient patients were younger and had higher levels of education (45.74 years old; high school or more: 90%) than minimally technologically proficient patients (53.64 years old; high school or more: 18%). Highly technologically proficient participants exchanged a mean of 40 text messages with the system coordinators compared to a mean of 10 text messages by minimally technologically proficient patients (P<.001). CONCLUSIONS: This study found that nearly half of the patients screened at the safety-net emergency department were equipped for an SMS text message-based mHealth intervention. In the small sample of patients who were enrolled, the majority were classified as highly technologically proficient. These highly proficient patients had greater study engagement. mHealth use in emergency departments may be an opportunity to improve health of ethnically diverse populations by pairing sophisticated chronic disease self-management program with SMS text message-based and traditional in-person interventions to reach patients through the method that is most familiar and comfortable. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1016/j.cct.2019.03.003.

The Onset-Offset N1-P2 Cortical Auditory Evoked Response in Individuals With High-Frequency Sensorineural Hearing Loss: Responses to High- and Low-Frequency Narrowband Noise.

PURPOSE: This study aimed to determine whether onset-offset N1-P2 auditory evoked responses differ in amplitude, latency, and offset-to-onset trough-to-peak N1-P2 amplitude ratios (OOAR) between normal hearing (NH) sensitivity and moderate high-frequency sensorineural hearing loss (HFSNHL) groups when stimuli target regions of peripheral hearing sensitivity where the groups are in the normal range (i.e., 500 Hz) versus where they differ regarding presence of hearing loss (i.e., 4000 Hz). METHOD: Onset-offset N1-P2 auditory evoked responses were measured from 10 participants with normal hearing sensitivity and seven participants with moderate HFSNHL using 500-Hz and 4000-Hz narrowband noise (NBN) stimuli. Stimuli were 2000 ms with 40-ms rise-fall times presented at 50 dB SL referenced to stimulus behavioral thresholds. Amplitudes and latencies were analyzed for N1 and P2 onset and offset components via repeated measures analysis of variance (ANOVA). OOARs were compared between groups using one-way ANOVA and across stimuli per group using paired samples t tests. RESULTS: Despite dB SPL stimulus presentation differences between groups, there were no significant differences in individual/absolute amplitude and latency waveform components between groups for either stimulus. Derived comparative calculations of OOAR for 4000-Hz NBN were significantly larger (p < .025; NH: .39; HFSNHL: .62) for the group with HFSNHL than the group with NH sensitivity; 500-Hz NBN OOAR did not reach significance. OOARs revealed no significant difference between stimuli for the group with normal hearing sensitivity, with .38 OOAR for both stimuli (p = .961). OOAR comparisons for the HFSNHL group across stimuli were significant (p = .012), with the 4000-Hz NBN OOAR being nearly double the size of the 500-Hz NBN OOAR. CONCLUSIONS: OOARs may provide insight to the balance of excitatory and inhibitory neural firing in the central auditory nervous system (CANS). Larger OOARs may be a biomarker of reduced CANS inhibition, perhaps indicative of a homeostatic central auditory gain mechanism.

Focusing on protective factors, resilience and thriving to reduce health disparities and treatment inequities.

This special issue seeks to characterize the current state of the science regarding risk and protective factors influencing resilience and thriving in relation to substance use among ethnic minorities and other underserved populations. This epilogue examines the scope of work presented in this special issue, the added value of the research presented herein, and how it can inform future research directions. Health disparities research can be conducted using two key approaches: 1) documenting between-group differences comparing ethnic/racial minorities groups and majority populations; or, 2) documenting within-group differences in a single racial or ethnic group. While characterization of between-group differences is useful to identify existing health disparities, it is essential to understand within-group diversity to fully address these inequities. Studies in this special issue identifying between- group differences focus on resiliency characteristics that could be present across all racial and ethnic groups. The studies examining within-group differences included in this special issue examine novel factors that influence resilience of protective health behaviors. Overall, this special issue examines several potential protective factors in the context of health promoting behaviors related to substance use using a wide range of research methodologies. While it is not exhaustive in its representation of all underserved populations experiencing health disparities and treatment inequities, this special issue includes a broad array of populations from various racial, ethnic, and national groups. Although we have to adequately explore thriving, the current special issue establishes a firm foundation for research on resilience that may extend to thriving.

Frecuencia de dientes humanos extraídos utilizados en el proceso educativo en las Facultades de Odontología del Paraguay en el año 2019 / Frequency of extracted human teeth used in the educational process in the Schools of Dentistry of Paraguay in the year 2019

El uso de dientes humanos como material didáctico para la enseñanza odontológica siempre ha sido fundamental, por lo que existe una gran demanda de estos para la formación del estudiante de odontología. El objetivo del trabajo fue determinar la cantidad de piezas dentarias utilizadas en el proceso de enseñanza/aprendizaje en las facultades de odontología del Paraguay en el año 2019. Se realizó un estudio observacional descriptivo de corte transversal, mediante un cuestionario semiestructurado enviado por correo electrónico a las Instituciones de Educación Superior del Paraguay (IES) del sector público y privado que poseen carreras de odontología habilitadas por el CONES. Se obtuvo una tasa de respuesta del 77,78% (n= 14). El 86% de las IES (n=12) mencionó utilizar dientes humanos extraídos para la investigación y el 100% los utilizó para la enseñanza preclínica de grado. En el año 2019 se utilizaron un total de 11.211 dientes para la enseñanza preclínica de grado. Se obtuvo que entre todas las IES, la cátedra que con mayor frecuencia utilizó dientes fue endodoncia del tercer curso. Los dientes humanos extraídos son solicitados para la enseñanza de grado en la totalidad de las IES del Paraguay que fueron encuestadas y es elevado el número de dientes que fueron utilizados. Este trabajo permitió dimensionar el uso de dientes humanos extraídos en la formación del alumno de odontología y demostrar la necesidad de establecer mecanismos para su obtención de forma ética y legal.

The use of human teeth as didactic material for dental education has always been fundamental, which is why there is a great demand for these for the training of dental students. The objective of the work was to determine the number of dental pieces used in the teaching/learning process in the dentistry schools of Paraguay in the year 2019. A cross-sectional descriptive observational study was carried out, through a semi- structured questionnaire sent by email to Higher Education Institutions of Paraguay from the public and private sectors that have dental careers authorized by CONES.: A response rate of 77.78% (n = 14) was obtained. 86% of HEIs (n=12) mentioned using extracted human teeth for research and 100% used them for undergraduate preclinical teaching. In 2019, a total of 11,211 teeth were used for undergraduate preclinical teaching. It was obtained that among all HEIs, the departments that most frequently used teeth were endodontics in the third year. Extracted human teeth are requested for undergraduate education in all the HEIs in Paraguay that were surveyed, and the number of teeth that were used is high. This work allowed dimensioning the use of extracted human teeth in the training of dentistry students and demonstrating the need to establish mechanisms to obtain them ethically and legally.