Diagnosis of heart failure with preserved ejection fraction: a systematic narrative review of the evidence.

Heart failure (HF) with preserved ejection fraction (HFpEF) is a common condition in clinical practice, affecting more than half of patients with HF. HFpEF is associated with morbidity and mortality and with considerable healthcare resource utilization and costs. Therefore, early diagnosis is crucial to facilitate prompt management, particularly initiation of sodium-glucose co-transporter 2 inhibitors. Although European guidelines define HFpEF as the presence of symptoms with or without signs of HF, left ventricular EF ≥ 50%, and objective evidence of cardiac structural and/or functional abnormalities, together with elevated natriuretic peptide levels, the diagnosis of HFpEF remains challenging. First, there is no clear consensus on how HFpEF should be defined. Furthermore, diagnostic tools, such as natriuretic peptide levels and resting echocardiogram findings, are significantly limited in the diagnosis of HFpEF. As a result, some patients are overdiagnosed (i.e., elderly people with comorbidities that mimic HF), although in other cases, HFpEF is overlooked. In this manuscript, we perform a systematic narrative review of the diagnostic approach to patients with HFpEF. We also propose a comprehensible algorithm that can be easily applied in daily clinical practice and could prove useful for confirming or ruling out a diagnosis of HFpEF.

A Lightweight Method for Detecting and Correcting Errors in Low-Frequency Measurements for In-Orbit Demonstrators.

In the pursuit of enhancing the technological maturity of innovative magnetic sensing techniques, opportunities presented by in-orbit platforms (IOD/IOV experiments) provide a means to evaluate their in-flight capabilities. The Magnetic Experiments for the Laser Interferometer Space Antenna (MELISA) represent a set of in-flight demonstrators designed to characterize the low-frequency noise performance of a magnetic measurement system within a challenging space environment. In Low Earth Orbit (LEO) satellites, electronic circuits are exposed to high levels of radiation coming from energetic particles trapped by the Earth's magnetic field, solar flares, and galactic cosmic rays. A significant effect is the accidental bit-flipping in memory registers. This work presents an analysis of memory data redundancy resources using auxiliary second flash memory and exposes recovery options to retain critical data utilizing a duplicated data structure. A new and lightweight technique, CCM (Cross-Checking and Mirroring), is proposed to verify the proper performance of these techniques. Four alternative algorithms included in the original version of the MELISA software (Version v0.0) are presented. All the versions have been validated and evaluated according to various merit indicators. The evaluations showed similar performances for the proposed techniques, and they are valid for situations in which the flash memory suffers from more than one bit-flip. The overhead due to the introduction of additional instructions to the main code is negligible, even in the target experiment based on an 8-bit microcontroller.

Exploiting the PIR Sensor Analog Behavior as Thermoreceptor: Movement Direction Classification Based on Spiking Neurons.

Pyroelectric infrared sensors (PIR) are widely used as infrared (IR) detectors due to their basic implementation, low cost, low power, and performance. Combined with a Fresnel lens, they can be used as a binary detector in applications of presence and motion control. Furthermore, due to their features, they can be used in autonomous intelligent devices or included in robotics applications or sensor networks. In this work, two neural processing architectures are presented: (1) an analog processing approach to achieve the behavior of a presynaptic neuron from a PIR sensor. An analog circuit similar to the leaky integrate and fire model is implemented to be able to generate spiking rates proportional to the IR stimuli received at a PIR sensor. (2) An embedded postsynaptic neuron where a spiking neural network matrix together with an algorithm based on digital processing techniques is introduced. This structure allows connecting a set of sensors to the post-synaptic circuit emulating an optic nerve. As a case study, the entire neural processing approach presented in this paper is applied to optical flow detection considering a four-PIR array as input. The results validate both the spiking approach for an analog sensor presented and the ability to retrieve the analog information sent as spike trains in a simulated optic nerve.

Resistance to 2-Hydroxy-Flutamide in Prostate Cancer Cells Is Associated with the Downregulation of Phosphatidylcholine Biosynthesis and Epigenetic Modifications.

In this study, we examined the metabolic adaptations of a chemoresistant prostate cancer cell line in comparison to a sensitive cell line. We utilized prostate cancer LNCaP cells and subjected them to a stepwise increase in the antiandrogen 2-hydroxy-flutamide (FLU) concentration to generate a FLU-resistant cell line (LN-FLU). These LN-FLU cells displayed characteristics of cancer stem cells, exhibited drug resistance, and showed a significantly reduced expression of Cyclin D1, along with the overexpression of p16, pointing to a proliferation arrest. In comparing the cancer stem-like LN-FLU cells to the LNCaP cells, we observed a decrease in the expression of CTP-choline cytidylyl transferase α (CCTα), as well as a decline in choline kinase, suggesting altogether a downregulation of the phosphatidylcholine biosynthetic pathway. In addition, we found decreased levels of the protein methyl transferase PRMT2 and the upregulation of the histone deacetylase Sirtuin1 (Sirt1). Analysis of the human prostate cancer samples revealed similar results in a population with high expressions of the stem cell markers Oct4 and ABCB1A1. Our findings suggest that the adaptation of prostate cancer cells to antiandrogens could induce reprogramming into stem cells that survive in a low phosphocholine metabolism and cell cycle arrest and display drug resistance.

Development of Communication Skills Through Virtual Reality on Nursing School Students: Clinical Trial.

Multiple studies demonstrate benefits of virtual simulations as recreation of reality in the development of instrumental skills, but few randomized studies prove its efficacy in the development of communication and interpersonal relationships skills. The objective was to develop a virtual reality simulator to improve communication skills and compare its results with a traditional workshop based on cases and theoretical content explained through video. This is a randomized and controlled clinical trial, with a pretest and a posttest. Participants were first-year students from the Faculty of Nursing, Complutense University of Madrid, Spain (n = 100). The sample was divided into two groups: the intervention group (n = 50) was provided a virtual reality simulation teaching process as a novel resource, whereas the control group was provided with a case-based traditional workshop. Because data followed a normal distribution, it was analyzed with Student t test for independent samples, the group sample comparison, and analysis of variance, to find differences among age subgroups. Significant changes were observed at the time of evaluating the skills for the intervention group ( P < .01) in comparison with the control group. Both interventions are effective after the first evaluation; however, virtual reality-based intervention stands above the usual method and showed better results in older students.

Data Compression in the NEXT-100 Data Acquisition System.

NEXT collaboration detectors are based on energy measured by an array of photomultipliers (PMT) and topological event filtering based on an array of silicon photomultipliers (SiPMs). The readout of the PMT sensors for low-frequency noise effects and detector safety issues requires a grounded cathode connection that makes the readout AC-couple with variations in the signal baseline. Strict detector requirements of energy resolution better than 1% FWHM require a precise baseline reconstruction that is performed offline for data analysis and detector performance characterization. Baseline variations make it inefficient to apply traditional lossy data compression techniques, such as zero-suppression, that help to minimize data throughput and, therefore, the dead time of the system. However, for the readout of the SiPM sensors with less demanding requirements in terms of accuracy, a traditional zero-suppression is currently applied with a configuration that allows for a compression ratio of around 71%. The third stage in the NEXT detectors program, the NEXT-100 detector, is a 100 kg detector that instruments approximately five times more PMT sensors and twice the number of SiPM sensors than its predecessor, the NEXT-White detector, putting more pressure in the DAQ throughput, expected to be over 900 MB/s with the current configuration, which will worsen the dead time of the acquisition data system. This paper describes the data compression techniques applied to the sensor data in the NEXT-100 detector, which reduces data throughput and minimizes dead time while maintaining the event rate to the level of its predecessor, around 50 Hz.

Fenestrated and Scalloped Endovascular Grafts in Zone 0 and Zone 1 for Aortic Arch Disease.

BACKGROUND: The aim of this study is to present midterm results of thoracic endovascular aortic repair (TEVAR) using scalloped or fenestrated custom-made endovascular grafts (CMEGs) in aortic arch Zones 0 and 1. METHODS: A retrospective review of prospectively collected data involving consecutive patients with aortic arch disease treated by scalloped or fenestrated Relay Plus stent grafts (Terumo Aortic, Sunrise, FL) landed in Zones 0 and 1. Patient demographics, operative details, clinical outcomes, and complications were analyzed. RESULTS: Between February 2014 and February 2020, 14 patients (9 male and 5 female) with a median age of 66 years (range 48-84) underwent scalloped or fenestrated TEVAR to preserve flow to the supra-aortic trunks (SATs). In 6 cases the landing zone was Zone 0 and in 8, Zone 1. Target vessels for the scallops were left common carotid artery in 8 cases (Zone 1) and innominate artery (IA) in 1 (Zone 0). All 5 fenestrations were designed to preserve the IA (Zone 0). Technical success was 100% with no endoleaks on completion angiography. One fatal perioperative stroke (7%) occurred in a patient with a fenestration for the IA and atherosclerotic plaques in the arch. During median follow-up of 37.5 (3-72) months, no other patient died, and all the target vessels and cervical revascularizations remained patent. There was no paraplegia, no retrograde dissection, and no other complication. Two patients (14%) with scallops in Zone 1 developed late endoleak: 1 type Ib at 6 months and 1 type Ia endoleak at 12 months. There were no endoleaks at all in the group of fenestrated endografts (Zone 0). CONCLUSIONS: When anatomy allows, endovascular treatment using scalloped or fenestrated CMEGs in Zones 0 and 1 is a feasible technique to treat patients with aortic arch disease involving the SATs.

HPV-based cervical cancer screening in Nicaragua: from testing to treatment.

BACKGROUND: In Nicaragua, cervical cancer is the leading cause of cancer death among women. Human papillomavirus (HPV) testing, primarily using self-sampling, was introduced between 2014 and 2018 in three provinces. We analyzed data from the HPV screening program with the goal of describing key characteristics including reach, HPV prevalence, triage and treatment, and factors associated with follow-up completion. METHODS: We analyzed individual-level data from routinely collected forms for women attending HPV-based cervical cancer screening. HPV-positive women were triaged with Pap or visual inspection with acetic acid (VIA) prior to treatment. Logistic regression was used to identify factors associated with receiving triage and treatment; analyses were adjusted for province, age, and self- vs. provider-collected sampling. RESULTS: Forty-four thousand six hundred thirty-five women were screened with HPV testing; 96.6% of women used self-sampling. Six thousand seven hundred seventy-six women were HPV positive (15.2%), 54.0% of screen-positive women received triage, and 53.1% of triage-positive women were treated, primarily with cryotherapy. If women lost at triage are included, the overall treatment percentage was 27.8%. Province and provider sampling were significantly associated with completing triage. Province and triage type were significantly associated with receiving treatment. The odds of receiving treatment after Pap triage as compared to VIA was significantly lower (aOR: 0.05, 95% CI: 0.04-0.08, p < 0.001), and the relative proportion of women receiving treatment after Pap triage versus VIA was 0.29. CONCLUSIONS: Introduction of HPV testing resulted in a substantial number of women screened, and acceptance of self-sampling was high. Management of screen-positive women remained a challenge, particularly with Pap triage. Our results can inform other developing countries as they work to reach World Health Organization (WHO) elimination targets.

Predictors of diffuse alveolar damage in patients with acute respiratory distress syndrome: a retrospective analysis of clinical autopsies.

BACKGROUND: Although diffuse alveolar damage (DAD) is considered the typical histological pattern of acute respiratory distress syndrome (ARDS), only half of patients exhibit this morphological hallmark. Patients with DAD may have higher mortality than those without DAD. Therefore, we aimed to identify the factors associated with DAD in patients with ARDS. METHODS: We analyzed autopsy samples of 356 patients who had ARDS at the time of death. DAD was assessed by two pathologists, and ARDS criteria were evaluated by two intensivists. Criteria for severe ARDS included the degree of hypoxemia and the ancillary variables of the current Berlin definition assessed within 48 h before death: radiographic severity, high positive end-expiratory pressure (PEEP) level, and physiological variables (i.e., altered respiratory system compliance and large anatomic dead space). RESULTS: After multivariable analysis, high PEEP levels, physiological variables, and opacities involving only three quadrants on chest radiographs were not associated with DAD. The four markers independently associated with DAD were (1) duration of evolution (OR 3.29 [1.95-5.55] for patients with ARDS ≥ 3 days, p < 0.001), (2) degree of hypoxemia (OR 3.92 [1.48-10.3] for moderate ARDS and 6.18 [2.34-16.3] for severe ARDS, p < 0.01 for both), (3) increased dynamic driving pressure (OR 1.06 [1.04-1.09], p = 0.007), and (4) radiographic severity (OR 2.91 [1.47-5.75] for patients with diffuse opacities involving the four quadrants, p = 0.002). DAD was found in two-thirds of patients with a ratio of partial pressure of arterial oxygen to fraction of inspired oxygen ≤ 100 mmHg and opacities involving the four quadrants. CONCLUSIONS: In addition to severe hypoxemia, diffuse opacities involving the four quadrants were a strong marker of DAD.

[Cost-effectiveness analysis of dapagliflozin compared to DPP4 inhibitors and other oral antidiabetic drugs in the treatment of type-2 diabetes mellitus in Spain]. / Análisis de coste-efectividad de dapagliflozina en comparación con los inhibidores de la DPP4 y otros antidiabéticos orales en el tratamiento de la diabetes mellitus tipo 2 en España.

OBJECTIVE: To assess the efficiency of the combined therapy with metformin and dapagliflozin, a new oral anti-diabetic drug with an insulin-independent mechanism of action, in the treatment of type-2 diabetes mellitus (T2DM) compared to DPP4 inhibitors, sulphonylureas and thiazolidindiones, also combined with metformin. DESIGN: Cost-effectiveness analysis using a discrete event simulation model based on the results of the available clinical trials and considering patient's entire life as time horizon. SETTING: National Health System perspective. PARTICIPANTS: The model simulated the natural history of 30,000 patients with T2DM for each of the options compared. MAIN MEASUREMENTS: Quality-adjusted life-years (QALY) and economic consequences of managing the disease and its complications. The analysis considered direct costs updated to 2013. A discount rate of 3% was applied to costs and health outcomes. RESULTS: In the main analysis comparing dapagliflozin with DPP4 inhibitors, dapagliflozin resulted in a treatment option that would provide a slightly higher effectiveness (0.019 QALY) and lower overall associated costs (-€42). In the additional analyses, dapagliflozin was a cost-effective option compared with sulphonylureas and thiazolidinediones resulting in a cost per QALY gained of €3,560 and €2,007, respectively. The univariate and probabilistic sensitivity analyses confirmed the robustness of the results. CONCLUSIONS: The results of the analyses performed suggested that dapagliflozin, in combination with metformin, would be a cost-effective alternative in the Spanish context for the treatment of T2DM.

[Profile dipper/non-dipper in patient with severe preeclampsia, eclampsia and HELLP syndrome during pregnancy and puerperium]. / Perfil dipper-no dipper en pacientes con preeclampsia severa, eclampsia y síndrome de Hellp durante el embarazo y puerperio.

BACKGROUND: Blood pressure (BP) has a circadian rhythm, decreases at night and increases in the morning (dipper), have been observed in patients with impaired in this profile, increased at night and lower in the morning (no dipper) have increased cardiovascular risk. Preeclampsia-eclampsia complicates about 7% of pregnancies, preeclampsia is known to reverse the normal circadian cycle of the BP. OBJECTIVE: To determine the profile dipper/non-dipper in patients with severe preeclampsia, eclampsia and HELLP syndrome patients in Intensive Care and Obstetrics Hospital Juárez of México. MATERIAL AND METHODS: 15 patients were reviewed, 10 with severe preeclampsia, 4 with HELLP syndrome and 1 eclampsia, systolic, diastolic, mean and pulse PA were analyzed during the day/night and pregnancy/postpartum. Using ratios pregnancy day/night pregnancy, puerperium day/night postpartum dipper/non-dipper profile is determined RESULTS: Maternal age 30 ± 6.34 years, 7 primiparous (46%) 8 multiparous (54%), pregnancy was 31.67 ± 4.59 weeks. In all but two results in the ratio of pulse pressure during pregnancy was not the result dipper raiser and did not change during the postpartum period. CONCLUSION: in all patients during pregnancy profile was observed no dipper no change during the postpartum period. The established treatment did not modify this result. So it is appropriate to establish strategies to change this behavior and try to get the patient to regain normal circadian BP rhythm.

Comparison of the Berlin definition for acute respiratory distress syndrome with autopsy.

RATIONALE: A revised definition of clinical criteria for acute respiratory distress syndrome (ARDS), the Berlin definition, was recently established to classify patients according to their severity. OBJECTIVE: To evaluate the accuracy of these clinical criteria using diffuse alveolar damage (DAD) at autopsy as the reference standard. METHODS: All patients who died and had a clinical autopsy in our intensive care unit over a 20-year period (1991-2010) were included. Patients with clinical criteria for ARDS were identified from the medical charts and were classified as mild, moderate, or severe according to the Berlin definition using PaO2/FiO2 oxygenation criteria. Microscopic analysis from each pulmonary lobe was performed by two pathologists. MEASUREMENTS AND MAIN RESULTS: Among 712 autopsies analyzed, 356 patients had clinical criteria for ARDS at time of death, classified as mild (n = 49, 14%), moderate (n = 141, 40%), and severe (n = 166, 46%). Sensitivity was 89% and specificity 63% to identify ARDS using the Berlin definition. DAD was found in 159 of 356 (45%) patients with clinical criteria for ARDS (in 12, 40, and 58% of patients with mild, moderate, and severe ARDS, respectively). DAD was more frequent in patients who met clinical criteria for ARDS during more than 72 hours and was found in 69% of those with severe ARDS for 72 hours or longer. CONCLUSIONS: Histopathological findings were correlated to severity and duration of ARDS. Using clinical criteria the revised Berlin definition for ARDS allowed the identification of severe ARDS of more than 72 hours as a homogeneous group of patients characterized by a high proportion of DAD.

Use of Periodic Mesoporous Organosilica-Benzene Adsorbent for CO2 Capture to Reduce the Greenhouse Effect.

The CO2 adsorption of a phenylene-bridged ordered mesoporous organosilica (PMO-benzene) was analyzed. The maximum capture capacity was 638.2 mg·g-1 (0 °C and 34 atm). Approximately 0.43 g would be enough to reduce the amount of atmospheric CO2 in 1 m3 to pre-industrial levels. The CO2 adsorption data were analyzed using several isotherm models, including Langmuir, Freundlich, Sips, Toth, Dubinin-Radushkevich, and Temkin models. This study confirmed the capability of this material for use in reversible CO2 capture with a minimal loss of capacity (around 1%) after 10 capture cycles. Various techniques were employed to characterize this material. The findings from this study can help mitigate the greenhouse effect caused by CO2.

CO2 Adsorption by CMK-3 at Low Temperatures and High Pressure to Reduce the Greenhouse Effect.

In this study, the maximum CO2 capture capacity of an ordered mesoporous carbon (CMK-3) was evaluated at high pressure (35 atm) and several temperatures (0, 10, 20, and 35 °C). CMK-3 was synthesized with the hard template method (silica SBA-15) using furfuryl alcohol and toluene as carbon sources. The CO2 adsorption isotherms were fitted to the following adsorption theories: Freundlich, Langmuir, Sips, Toth, Dubinin-Radushkevich, and Temkin. The maximum capture capacity (726.7 mg·g-1) was achieved at 0 °C and 34 atm. The results of the study of successive adsorption-desorption cycles showed that multi-cycle reversible gas capture processes could be used in optimal temperature and pressure conditions. It was determined that 0.478 g of CMK-3 would be required to reduce the CO2 concentration in 1 m3 of air to pre-industrial levels (280 ppm). The obtained results may contribute to technological developments for the mitigation of human impacts on the environment through the capture of atmospheric CO2.

Diabetic individuals with COVID-19 exhibit reduced efficacy of gliptins in inhibiting dipeptidyl peptidase 4 (DPP4). A suggested explanation for increased COVID-19 susceptibility in patients with type 2 diabetes mellitus (T2DM).

AIMS: Dipeptidyl peptidase 4 (DPP4) has been proposed as a coreceptor for SARS-CoV-2 cellular entry. Considering that type 2 diabetes mellitus (T2DM) has been identified as the most important risk factor for SARS-CoV-2, and that gliptins (DPP4 inhibitors) are a prescribed diabetic treatment, this study aims to unravel the impact of DPP4 in the intersection of T2DM/COVID-19. MATERIALS AND METHODS: We analyzed 189 serum human samples, divided into six clinical groups (controls, T2DM, T2DM + gliptins, COVID-19, COVID-19 + T2DM, and COVID-19 + T2DM + gliptins), measuring DPP4 protein concentration and activity by Western blot, ELISA, and commercial activity kits. The obtained results were verified in Huh-7 cellular models. KEY FINDINGS: Both DPP4 concentration and activity were decreased in COVID-19 patients, and as in T2DM patients, compared to controls. Despite these lower levels, the ratio of DPP4 activity/concentration in COVID-19 sera was the highest (0.782 ± 0.289 µU/ng vs. 0.547 ± 0.050 µU/ng in controls, p < 0.0001), suggesting a compensating mechanism in these patients. Supernatants of Huh-7 cells incubated with COVID-19 serum showed a consistent and significantly lower DPP4 concentration and activity. Furthermore, COVID-19 + T2DM + gliptins patients showed a higher serum DPP4 concentration and activity than T2DM + gliptin subjects (p < 0.05), indicating that sera from COVID-19 convalescents interfere with gliptins. SIGNIFICANCE: Either SARS-CoV-2 or some metabolites present in the sera of COVID-19-convalescent patients interact with soluble DPP4 or even gliptins themselves since the inhibitory effect of gliptins on DPP4 activity is being prevented. The interactions between DPP4, gliptins, and SARS-CoV-2 should be further elucidated to reveal the mechanism of action for these interesting observations.

Use of Milled Acanthocardia tuberculate Seashell as Fine Aggregate in Self-Compacting Mortars.

This study focuses on the feasibility of using ground Acanthocardia tuberculate seashells as fine aggregates for self-compacting mortar production. The obtained results show a promising future for coastal industries as their use eliminates waste products and improves the durability of these materials. The use of Acanthocardia tuberculate recycled aggregate, in terms of durability, improves the performance of all mixes made with seashells compared to those made with natural sand, although it decreases workability and slightly reduces mechanical strength. Proper mix design has beneficial effects, as it improves compressive strength, especially when the powder/sand ratio is 0.7. Three replacement ratios based on the volume (0%, 50%, and 100%) of natural limestone sand with recycled fine aggregate from Acanthocardia tuberculate seashells, and three different dosages modifying the powder/sand ratio (0.6, 0.7, and 0.8), were tested. The fresh-state properties of each self-compacting mixture were evaluated based on workability. The mineralogical phases of the hardened mixtures were characterised using X-ray diffraction, thermogravimetry, and differential analyses. Subsequently, the mechanical and durability properties were evaluated based on the compressive and flexural strengths, dry bulk density, accessible porosity for water and water absorption, drying shrinkage, mercury intrusion porosimetry, and water absorption by capillarity. Therefore, the use of Acanthocardia tuberculate seashells in cement-based systems contributes to circular economy.

The significance of metabolic alkalosis on acute decompensated heart failure: the ALCALOTIC study.

AIMS: To determine the prevalence and the impact on prognosis of metabolic alkalosis (MA) in patients admitted for acute heart failure (AHF). METHODS AND RESULTS: The ALCALOTIC is a multicenter, observational cohort study that prospectively included patients admitted for AHF. Patients were classified into four groups according to their acid-base status on admission: acidosis, MA, respiratory alkalosis, and normal pH (reference group for comparison). Primary endpoint was all-cause in-hospital mortality, and secondary endpoints included 30/90-day all-cause mortality, all-cause readmission, and readmission for HF. Associations between endpoints and acid-base alterations were estimated in a multivariate Cox regression model including sex, age, comorbidities, and Barthel index and expressed as hazard ratio (HR) with 95% confidence interval (95% CI). Six hundred sixty-five patients were included (84 years and 57% women), and 40% had acid-base alterations on admission: 188 (28%) acidosis and 78 (12%) alkalosis. The prevalence (95% CI) of MA was 9% (6.8-11.2%). Patients with MA were more women; had fewer comorbidities, better renal function, and higher left ventricle ejection fraction values; and received more treatment with oral acetazolamide during hospitalization and at discharge. MA was not associated with a higher risk of in-hospital mortality and 30/90-day all-cause mortality or readmissions but was associated with a significant increase in readmissions for HF at 30 and 90 days (adjusted HR [95% CI] 3.294 [1.397-7.767], p = 0.006 and 2.314 [1.075-4.978], p = 0.032). CONCLUSION: The prevalence of MA in patients admitted for AHF was 9%, and its presence was associated with more readmissions for HF but not with all-cause mortality.

[The religious aspects of maternal mortality at the time of the Aztecs. Cihuateteo: dead women at first birth]. / Aspectos religiosos de la mortalidad materna en la época de los aztecas. Cihuateteo: las mujeres muertas en el primer parto.

Women who die during pregnancy or childbirth, the Aztec goddess regarded with the same value that was given to the warriors who died on the battlefield, accompanied the sun during its journey through the land, but were also feared and regarded as witches who could fly and cause damage and disease to children, could occupy bodies and produce paralysis, at the funeral the relatives of the Cihuateteo should take care of the woman's body because there was a possibility that parts of soldiers stealing him to gain courage in battle. The governing Cihuateteo magical occupations of women.