Severe Inflammatory and Disseminated Cutaneous Leishmaniasis in a Pregnant Woman: A Case Report from Portoviejo, Ecuador.

BACKGROUND Leishmaniasis is a zoonosis with worldwide prevalence that causes dermal lesions and can be serious in humans. This report presents a case of cutaneous leishmaniasis (CL) that was apparently associated with a zoonotic transmission in a peri-urban area of the city of Portoviejo, Ecuador, close to mountainous and forested sites. CASE REPORT For 37 years, we have studied transmission of leishmaniasis in Ecuador, and have seen a wide variety of clinical presentations of the disease caused by different strains of the parasite Leishmania in patients, including pregnant women, without marked difference among them. CL without complications causes painless lesions of different clinical aspect. The present study reports a case of a 25-year-old woman presenting with severely inflamed, disseminated, and painful lesions of CL. The patient was not given antimonial treatment; however, local cryotherapy was given, together with topical anti-inflammatory and antibiotic ointment. All the lesions were observed to heal, and no amastigotes were found in smear stains after clinical healing. Since there was no reactivation after 1.5 years of follow-up, conventional antileishmanial treatment with meglumine antimoniate was not given to the patient. CONCLUSIONS This report shows the importance of a properly done epidemiological and clinical presumtive diagnosis, followed by parasitological confirmation, and the benefit of using an alternative treatment for vulnerable patients, such as this pregnant woman, for whom the therapy with pentavalent antimonials is not indicated. All observed lesions healed and no amastigotes were found in the smears after clinical healing.

An observational analysis on the influence of parental allergic rhinitis, asthma and smoking on exhaled nitric oxide in offspring.

BACKGROUND: Parental allergic diseases and smoking influence respiratory disease in the offspring but it is not known whether they influence fractional exhaled nitric oxide (FeNO) in the offspring. We investigated whether parental allergic diseases, parental smoking and FeNO levels in parents were associated with FeNO levels in their offspring. METHODS: We studied 609 offspring aged 16-47 years from the Respiratory Health in Northern Europe, Spain and Australia generation (RHINESSA) study with parental information from the Respiratory Health in Northern Europe (RHINE) III study and the European Community Respiratory Health Survey (ECRHS) III. Linear regression models were used to assess the association between offspring FeNO and parental FeNO, allergic rhinitis, asthma and smoking, while adjusting for potential confounding factors. RESULTS: Parental allergic rhinitis was significantly associated with higher FeNO in the offspring, both on the paternal and maternal side (percent change: 20.3 % [95%CI 5.0-37.7], p = 0.008, and 13.8 % [0.4-28.9], p = 0.043, respectively). Parental allergic rhinitis with asthma in any parent was also significantly associated with higher offspring FeNO (16.2 % [0.9-33.9], p = 0.037). However, parental asthma alone and smoking were not associated with offspring FeNO. Parental FeNO was not associated with offspring FeNO after full adjustments for offspring and parental factors. CONCLUSIONS: Parental allergic rhinitis but not parental asthma was associated with higher levels of FeNO in offspring. These findings suggest that parental allergic rhinitis status should be considered when interpreting FeNO levels in offspring beyond childhood.

Uric acid and acute kidney injury in high-risk patients for developing acute kidney injury undergoing cardiac surgery: A prospective multicenter study.

PURPOSE: It is unclear whether preoperative serum uric acid (SUA) elevation may play a role in the development of acute kidney injury (AKI) associated with cardiac surgery (CSA-AKI). We conducted a cohort study to evaluate the influence of preoperative hyperuricemia on AKI in patients at high risk for developing SC-AKI. DESIGN: Multicenter prospective international cohort study. SETTING: Fourteen university hospitals in Spain and the United Kingdom. PARTICIPANTS: We studied 261 consecutive patients at high risk of developing CSA-AKI, according to a Cleveland score ≥ 4 points, from July to December 2017. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: AKIN criteria were used for the definition of AKI. Multivariable logistic regression models and propensity score-matched pairwise analysis were used to determine the adjusted association between preoperative hyperuricemia (≥7 mg/dL) and AKI. Elevated preoperative AUS (≥7 mg/dL) was present in 190 patients (72.8%), whereas CSA-AKI occurred in 145 patients (55.5%). In multivariable logistic regression models, hyperuricemia was not associated with a significantly increased risk of AKI (adjusted Odds Ratio [OR]: 1.58; 95% confidence interval [CI]: 0.81-3; P = .17). In propensity score-matched analysis of 140 patients, the hyperuricemia group experienced similar adjusted odds of AKI (OR 1.05, 95%CI 0.93-1.19, P = .37). CONCLUSIONS: Hyperuricemia was not associated with an increased risk of AKI in this cohort of patients undergoing cardiac surgery at high risk of developing CSA-AKI.

Bioarchaeology aids the cultural understanding of six characters in search of their agency (Tarquinia, ninth-seventh century BC, central Italy).

Etruria contained one of the great early urban civilisations in the Italian peninsula during the first millennium BC, much studied from a cultural, humanities-based, perspective, but relatively little with scientific data, and rarely in combination. We have addressed the unusual location of twenty inhumations found in the sacred heart of the Etruscan city of Tarquinia, focusing on six of these as illustrative, contrasting with the typical contemporary cremations found in cemeteries on the edge of the city. The cultural evidence suggests that the six skeletons were also distinctive in their ritualization and memorialisation. Focusing on the six, as a representative sample, the scientific evidence of osteoarchaeology, isotopic compositions, and ancient DNA has established that these appear to show mobility, diversity and violence through an integrated bioarchaeological approach. The combination of multiple lines of evidence makes major strides towards a deeper understanding of the role of these extraordinary individuals in the life of the early city of Etruria.

Discriminating organic carbon from endokarstic moonmilk-type deposits by LIBS. The case of a natural carbonated Martian analogue.

Moonmilk-type deposits exemplify carbonated Martian analogues existing in the subsurface of Earth, an endokarstic speleothem with a possible biochemical origin composed principally by carbonates, mainly huntite and dolomite. In this work, samples of moonmilk located in Nerja Cave (southern Spain) have been studied by LIBS with the aim of identifying carbon of biogenic origin by establishing a relationship between a molecular emission indicator, CN signal, and the organic carbon content. The characterization of this kind of carbonate deposit with a multiple mineralogical composition has been completed using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction techniques for qualitative and semi-quantitative analysis. The information attained from LIBS regarding energy thresholds and time-resolved kinetics of CN emissions provides useful insight into the identification of different molecular emitters, namely organic and inorganic CN, depending on the laser irradiance and time settings conditions. These promising results are of application in the search and identification of biosignatures in upcoming planetary missions with astrobiological purposes.

Bemisia tabaci MEAM1 still remains the dominant species in open field crops in Brazil

Abstract Among Bemisia tabaci species, the invasive MEAM1 and MED species are key agricultural pests for many crops. In Brazil, most part of B. tabaci population outbreaks were associated with MEAM1, which, since 1990s quickly spread across the entire country. Later in 2014, the MED was identified in Brazil, initially more restricted to greenhouses, but suddenly reaching new areas in the South and Southeast open regions. Thus, our objective was to investigate the geographical distribution of MEAM1 and MED on open field crops in Brazil. MEAM1 is still the predominant species on open field crops such as soybean, cotton, and tomato. The sequencing of a cytochrome c oxidase subunit I (COI) gene fragment revealed a single haplotype of MEAM1, suggesting the establishment of a single MEAM1 strain in the country. The haplotypes found for MEAM1 and MED are genetically related to the globally dispersed strains, Jap1 and Mch1, respectively. Continuous monitoring of B. tabaci species is crucial because landscape alterations, climatic changes, and pest management methods may shift the B. tabaci species distribution and dominance in Brazilian crop areas.

Resumo Dentre as espécies de Bemisia tabaci, as espécies invasoras MEAM1 e MED se destacam como pragas de grande importância para várias culturas. No Brasil, a maior parte dos surtos populacionais de mosca-branca são associados a presença da espécie MEAM1, que a partir 1990 se espalhou por todo o país. Por outro lado, em 2014 a espécie MED foi identificada no Brasil, inicialmente restrita a casas de vegetação, mas rapidamente se difundindo em novas áreas nas regiões Sul e Sudeste do Brasil. Assim, nosso objetivo foi investigar a distribuição geográfica das espécies MEAM1 e MED em grandes culturas no Brasil. A espécie MEAM1 continua sendo predominante nas monoculturas como algodão, soja e tomate. O sequenciamento de um fragmento do gene citocromo c oxidase subunidade I (COI) revelou a presença de um haplótipo para MEAM1, sugerindo o estabelecimento de apenas uma linhagem no país. Os haplótipos encontrados para MEAM1 e MED são geneticamente relacionados as linhagens globalmente dispersas Jap1 e Mch1, respectivamente. O monitoramento contínuo das espécies de B. tabaci é crucial pois as mudanças na paisagem, mudanças climáticas e métodos de manejo das pragas podem alterar a dominância e a distribuição dessas espécies nas áreas agrícolas do Brasil.

Bemisia tabaci MEAM1 still remains the dominant species in open field crops in Brazil / Bemisia tabaci MEAM1 ainda é a espécie dominante em cultivos a céu aberto no Brasil

Among Bemisia tabaci species, the invasive MEAM1 and MED species are key agricultural pests for many crops. In Brazil, most part of B. tabaci population outbreaks were associated with MEAM1, which, since 1990s quickly spread across the entire country. Later in 2014, the MED was identified in Brazil, initially more restricted to greenhouses, but suddenly reaching new areas in the South and Southeast open regions. Thus, our objective was to investigate the geographical distribution of MEAM1 and MED on open field crops in Brazil. MEAM1 is still the predominant species on open field crops such as soybean, cotton, and tomato. The sequencing of a cytochrome c oxidase subunit I (COI) gene fragment revealed a single haplotype of MEAM1, suggesting the establishment of a single MEAM1 strain in the country. The haplotypes found for MEAM1 and MED are genetically related to the globally dispersed strains, Jap1 and Mch1, respectively. Continuous monitoring of B. tabaci species is crucial because landscape alterations, climatic changes, and pest management methods may shift the B. tabaci species distribution and dominance in Brazilian crop areas.

Dentre as espécies de Bemisia tabaci, as espécies invasoras MEAM1 e MED se destacam como pragas de grande importância para várias culturas. No Brasil, a maior parte dos surtos populacionais de mosca-branca são associados a presença da espécie MEAM1, que a partir 1990 se espalhou por todo o país. Por outro lado, em 2014 a espécie MED foi identificada no Brasil, inicialmente restrita a casas de vegetação, mas rapidamente se difundindo em novas áreas nas regiões Sul e Sudeste do Brasil. Assim, nosso objetivo foi investigar a distribuição geográfica das espécies MEAM1 e MED em grandes culturas no Brasil. A espécie MEAM1 continua sendo predominante nas monoculturas como algodão, soja e tomate. O sequenciamento de um fragmento do gene citocromo c oxidase subunidade I (COI) revelou a presença de um haplótipo para MEAM1, sugerindo o estabelecimento de apenas uma linhagem no país. Os haplótipos encontrados para MEAM1 e MED são geneticamente relacionados as linhagens globalmente dispersas Jap1 e Mch1, respectivamente. O monitoramento contínuo das espécies de B. tabaci é crucial pois as mudanças na paisagem, mudanças climáticas e métodos de manejo das pragas podem alterar a dominância e a distribuição dessas espécies nas áreas agrícolas do Brasil.

Scaphanocephalus spp. (Trematoda: Opisthorchiidae) in intermediate and definitive hosts of the Yucatán Peninsula, Mexico, with a re-description of Scaphanocephalus expansus.

Scaphanocephalus is a small trematode genus belonging to the family Opistorchiidae. The genus currently contains only three species associated with marine fish as intermediate hosts and fish-eating birds as definitive hosts. Here, specimens of Scaphanocephalus were collected from the Osprey, Pandion haliaetus, and the White mullet, Mugil curema in the Yucatán Peninsula, Mexico. We report for the first-time DNA sequences of adult specimens of Scaphanocephalus, particularly S. expansus, as well as a sequence of a different species sampled as metacercaria. Morphological comparisons of Scaphanocephalus expansus confirmed the identity of the adult specimens, with minor morphological variations; Scanning electron photomicrographs were included, and the species was re-described. Phylogenetic analysis based on 28S rDNA sequences showed that Scaphanocephalus is monophyletic within Opisthorchiidae and consists of three independent lineages. Sequences of adults are identical to those of S. expansus. Instead, the sequence of the metacercaria sampled from the mesentery of Mugil curema nested with specimens reported as Scaphanocephalus sp. from a labrid fish in the Mediterranean Sea, herein named it as Scaphanocephalus sp. 2.

Molecular Oxygen Trimer: Multiplet Structures and Stability.

We present a detailed theoretical study of the molecular oxygen trimer where the potential energy surfaces of the seven multiplet states have been calculated by means of a pair approximation with very accurate dimer ab initio potentials. In order to obtain all the states a matrix representation of the potential using the uncoupled spin representation has been applied. The S = 0 ${S = 0}$ and S = 1 ${S = 1}$ states are nearly degenerate and low-lying isomers appear for most multiplicities. A crucial point in deciding the relative stabilities is the zero-point energy which represents a sizable fraction of the electronic well-depth. Therefore, we have performed accurate diffusion Monte Carlo studies of the lowest state in each multiplicity. Analysis of the wavefunction allows a deeper interpretation of the cluster structures, finding that they are significantly floppy in most cases.

Multi-analytical characterization of an oncoid from a high altitude hypersaline lake using techniques employed in the Mars2020 and Rosalind Franklin missions on Mars.

In this work, a geological sample of great astrobiological interest was studied through analytical techniques that are currently operating in situ on Mars and others that will operate in the near future. The sample analyzed consisted of an oncoid, which is a type of microbialite, collected in the Salar Carachi Pampa, Argentina. The main peculiarity of microbialites is that they are organo-sedimentary deposits formed by the in situ fixation and precipitation of calcium carbonate due to the growth and metabolic activities of microorganisms. For this reason, the Carachi Pampa oncoid was selected as a Martian analog for astrobiogeochemistry study. In this sense, the sample was characterized by means of the PIXL-like, SuperCam-like and SHERLOC-like instruments, which represent instruments on board the NASA Perseverance rover, and by means of RLS-like and MOMA-like instruments, which represent instruments on board the future ESA Rosalind Franklin rover. It was possible to verify that the most important conclusions and discoveries have been obtained from the combination of the results. Likewise, it was also shown that Perseverance rover-like remote-sensing instruments allowed a first detailed characterization of the biogeochemistry of the Martian surface. With this first characterization, areas of interest for in-depth analysis with Rosalind Franklin-like instruments could be identified. Therefore, from a first remote-sensing elemental identification (PIXL-like instrument), followed by a remote-sensing molecular characterization (SuperCam and SHERLOC-like instruments) and ending with an in-depth microscopic analysis (RLS and MOMA-like instruments), a wide variety of compounds were found. On the one hand, the expected minerals were carbonates, such as aragonite, calcite and high-magnesium calcite. On the other hand, unexpected compounds consisted of minerals related to the Martian/terrestrial surface (feldspars, pyroxenes, hematite) and organic compounds related to the past biological activity related to the oncoid (kerogen, lipid biomarkers and carotenes). Considering samples resembling microbialites have already been found on Mars and that one of the main objectives of the missions is to identify traces of past life, the study of microbialites is a potential way to find biosignatures protected from the inhospitable Martian environment. In addition, it should be noted that in this work, further conclusions have been obtained through the study of the results as a whole, which could also be carried out on Mars.

Development and validation of an infrared-artificial intelligence software for breast cancer detection.

Aim: In countries where access to mammography equipment and skilled personnel is limited, most breast cancer (BC) cases are detected in locally advanced stages. Infrared breast thermography is recognized as an adjunctive technique for the detection of BC due to its advantages such as safety (by not emitting ionizing radiation nor applying any stress to the breast), portability, and low cost. Improved by advanced computational analytics techniques, infrared thermography could be a valuable complementary screening technique to detect BC at early stages. In this work, an infrared-artificial intelligence (AI) software was developed and evaluated to help physicians to identify potential BC cases. Methods: Several AI algorithms were developed and evaluated, which were learned from a proprietary database of 2,700 patients, with BC cases that were confirmed through mammography, ultrasound, and biopsy. Following by evaluation of the algorithms, the best AI algorithm (infrared-AI software) was submitted to a clinic validation process in which its ability to detect BC was compared to mammography evaluations in a double-blind test. Results: The infrared-AI software demonstrated efficiency values of 94.87% sensitivity, 72.26% specificity, 30.08% positive predictive value (PPV), and 99.12% negative predictive value (NPV), whereas the reference mammography evaluation reached 100% sensitivity, 97.10% specificity, 81.25% PPV, and 100% NPV. Conclusions: The infrared-AI software here developed shows high BC sensitivity (94.87%) and high NPV (99.12%). Therefore, it is proposed as a complementary screening tool for BC.

How heat waves, ozone and sunlight hours affect endocrine and metabolic diseases emergency admissions? A case study in the region of Madrid (Spain).

BACKGROUND: Studies which analyse the joint effect of acoustic or chemical air pollution variables and different meteorological variables on neuroendocrine disease are practically nonexistent. This study therefore sought to analyse the impact of air pollutants and environmental meteorological variables on daily unscheduled admissions due to endocrine and metabolic diseases in the Madrid Region from January 01, 2013 to December 31, 2018. MATERIAL AND METHODS: We conducted a longitudinal, retrospective, ecological study of daily time series analysed by Poisson regression, with emergency neuroendocrine-disease admissions in the Madrid Region as the dependent variable. The independent variables were: mean daily concentrations of PM10, PM2.5, NO2 and O3; acoustic pollution; maximum and minimum daily temperatures; hours of sunlight; relative humidity; wind speed; and air pressure above sea level. Estimators of the statistically significant variables were used to calculate the relative risks (RRs). RESULTS: A statistically significant association was found between the increase in temperatures in heat waves, RR: 1.123 95% CI (1.001-1.018), and the number of emergency admissions, making it the main risk factor. An association between a decrease in sunlight and an increase in hospital admissions, RR: 1.005 95% CI (1.002 1.008), was likewise observed. Similarly, ozone, in the form of mean daily concentrations in excess of 44 µg/m3, had an impact on admissions due to neuroendocrine disease, RR: 1.010 95% CI (1.007-1.035). The breakdown by sex showed that in the case of women, NO2 was also a risk factor, RR: 1.021 95% CI (1.007-1.035). CONCLUSION: The results obtained in this study serve to identify risk factors for this disease, such as extreme temperatures in heat waves, O3 or NO2. The robust association found between the decrease in sunlight and increase in hospital admissions due to neuroendocrine disease serves to spotlight an environmental factor which has received scant attention in public health until now.

Phylogenetic analyses based on molecular and morphological data reveal a new species of Strigea Abildgaard, 1790 (Digenea: Strigeidae) and taxonomic changes in strigeids infecting Neotropical birds of prey.

Members of the genus Strigea Abildgaard, 1790 are endoparasites of birds distributed worldwide. Adults of an undescribed species of the genus Strigea were collected from the intestines of two hawk species (Rupornis magnirostris and Accipiter coperii). Other species identified as Parastrigea macrobursa that were described in Argentina were also recovered from two hawk species (Buteogallus urubitinga and Buteogallus anthracinus) in three localities along the coasts of Mexico. Specimens of the two species were sequenced for three molecular markers, the internal transcribed spacers locus (ITS1-5.8S rDNA- ITS2) and the domains D1-D3 from the large subunit from nuclear ribosomal DNA and the cytochrome c oxidase subunit 1 from mitochondrial DNA. The newly sequenced specimens were aligned with other strigeids sequences downloaded from GenBank. Maximum likelihood and Bayesian analyses inferred with each molecular marker revealed that our specimens of Strigea sp. formed an independent lineage, which is recognized herein as a new species, Strigea magnirostris n. sp., representing the first species in Mexico and the 16th in the Neotropical region. Morphologically, the new species is distinguished from other congeneric species from the Americas by having an oral sucker with several papillae around it, well-developed pseudosuckers (118-248 µm), a tegument covered with tiny spines, a larger cone genital (193-361 × 296-637) and a larger copulatory bursa (247-531 × 468-784). Our phylogenetic analyses revealed that P. macrobursa is not closely related to other members of the genus Parastrigea and is nested within Strigea, suggesting that P. macrobursa should be transferred to Strigea to form Strigea macrobursa n. comb., expanding its distribution range from Mexico to Argentina. Finally, the analyses also revealed that the taxonomy and systematics of Strigea should be re-evaluated, combining morphological and molecular characteristics.

Modelo animal de ectasia corneal en conejo mediante inyección intraestromal de colagenasa tipo ii / Animal model of corneal ectasia in rabbits by intrastromal injection of type II collagenase

Introducción La colagenasa ii ha sido utilizada para inducir queratocono experimental en modelos animales. Sin embargo, no ha sido estudiado su efecto cuando se administra por inyección intraestromal, por lo que el propósito de este estudio fue estudiar los efectos de la inyección intraestromal de colagenasa ii sobre la superficie corneal y la morfología de la córnea. Método Se trabajó con 6 conejos Nueva Zelanda, se administró colagenasa ii por inyección intraestromal (5μL de 2,5mg/mL) en los ojos derechos y solución salina balanceada en los ojos izquierdos. Se realizaron queratometrías para evaluar la alteración de la curvatura, también al séptimo día se obtuvieron las córneas y se realizó tinción hematoxilina-eosina para examinar los cambios morfológicos. Asimismo, se investigaron los cambios en la expresión de colágeno tipo i por tinción rojo sirio y PCR semicuantitativa. Resultados K1, K2 y Km presentaron diferencias en los promedios con cambios estadísticamente significativos. Los cambios morfológicos que se demostraron fueron degradación y disposición irregular del estroma corneal, incremento en la densidad celular de queratocitos y ligera infiltración celular. Finalmente se demostró que hay mayor expresión de fibras de colágeno tipo i en el grupo experimental a diferencia de los controles y el grosor de las fibras también aumentó por acción de la colagenasa ii; sin embargo, en cuestión génica no hubo cambios en la expresión de colágeno tipo i a nivel molecular entre el grupo control y experimental. Conclusiones La colagenasa ii administrada por inyección intraestromal es capaz de inducir cambios en la superficie corneal y el estroma, pudiendo simular un modelo de queratocono (AU)

Introduction Collagenase II has been used to induce experimental keratoconus in animal models. However, its effect when administered by intrastromal injection has not been studied, so the purpose of this study was to study the effects of intrastromal injection of collagenase II on corneal surface and corneal morphology. Method Six New Zealand rabbits were used, collagenase II was administered by intrastromal injection (5μL of 2.5mg/mL) in the right eyes and balanced salt solution in the left eyes. Keratometry was performed to evaluate curvature alteration, also at day 7 corneas were obtained and hematoxylin–eosin staining was performed to examine morphologic changes. Likewise, changes in type I collagen expression were investigated by Sirius Red staining and semi-quantitative PCR. Results K1, K2, and Km presented differences in the means with statistically significant changes. The morphological changes that were demonstrated were degradation and irregular arrangement of the corneal stroma, increase in the cellular density of keratocytes and slight cellular infiltration. Finally, it was demonstrated that there is greater expression of type I collagen fibers in the experimental group as opposed to the controls and the thickness of the fibers also increased due to the action of collagenase II, however, in terms of genetics there were no changes in the expression of type I collagen at molecular level between the control and experimental groups. Conclusions Collagenase II administered by intrastromal injection is able to induce changes in the corneal surface and stroma, being able to simulate a model of keratoconus (AU)

Animal model of corneal ectasia in rabbits by intrastromal injection of type II collagenase.

INTRODUCTION: Collagenase II has been used to induce experimental keratoconus in animal models. However, its effect when administered by intrastromal injection has not been studied, so the purpose of this study was to study the effects of intrastromal injection of collagenase II on corneal surface and corneal morphology. METHODS: Six New Zealand rabbits were used, collagenase II was administered by intrastromal injection (5µL of 2.5mg/mL) in the right eyes and balanced salt solution in the left eyes. Keratometry was performed to evaluate curvature alteration, also at day 7 corneas were obtained and Hematoxylin-Eosin staining was performed to examine morphologic changes. Likewise, changes in type I collagen expression were investigated by Sirius Red staining and semiquantitative PCR. RESULTS: K1, K2 and Km presented differences in the means with statistically significant changes. The morphological changes that were demonstrated were degradation and irregular arrangement of the corneal stroma, increase in the cellular density of keratocytes and slight cellular infiltration. Finally, it was demonstrated that there is greater expression of type I collagen fibers in the experimental group as opposed to the controls and the thickness of the fibers also increased due to the action of collagenase II, however, in terms of genetics there were no changes in the expression of type I collagen at molecular level between the control and experimental groups. CONCLUSIONS: Collagenase II administered by intrastromal injection is able to induce changes in the corneal surface and stroma, being able to simulate a model of keratoconus.