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Lyme disease is a multisystem disorder transmitted through the Ixodes tick and is most commonly diagnosed in northeastern and mid-Atlantic states, Wisconsin, and Minnesota, though its disease borders are expanding in the setting of climate change. Approximately 10%-15% of untreated Lyme disease cases will develop neurologic manifestations of Lyme neuroborreliosis (LNB). Due to varying presentations, LNB presents diagnostic challenges and is associated with a delay to treatment. We discuss three cases of LNB admitted to our referral center in a traditionally low-incidence state to highlight clinical pearls in LNB diagnosis. Three patients from low-incidence areas with prior diagnostic evaluations presented in August with neurologic manifestations of radiculoneuritis, cranial neuropathies, and/or lymphocytic meningitis. MRI findings included cranial nerve, nerve root, and leptomeningeal enhancement leading to broad differential diagnoses. Lumbar puncture demonstrated lymphocytic pleocytosis (range 85-753 cells/uL) and elevated protein (87-318 mg/dL). Each patient tested positive for Lyme on two-tiered serum testing and was diagnosed with LNB. All three cases were associated with a delay to health care presentation (mean 20 days) and a delay to diagnosis and treatment (mean 54 days) due to under-recognition and ongoing evaluation. With the geographic expansion of Lyme disease, increasing awareness of LNB manifestations and acquiring detailed travel histories in low-incidence areas is crucial to prompt delivery of care. Clinicians should be aware of two-tiered serum diagnostic requirements and use adjunctive studies such as lumbar puncture and MRI to eliminate other diagnoses. Treatment with an appropriate course of antibiotics leads to robust improvement in neurological symptoms.

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Brain metastases are a significant source of morbidity and mortality in patients with non-small cell lung cancer. Historically, surgery and radiation therapy have been essential to maintaining disease control within the central nervous system due to poorly penetrant conventional chemotherapy. With the advent of targeted therapy against actionable driver mutations, there is potential to control limited and asymptomatic intracranial disease and delay local therapy until progression. In this review paper, intracranial response rates and clinical outcomes to biological and immune therapies are summarized from the literature and appraised to assist clinical decision making and identify areas for further research. Future clinical trials ought to prioritize patient-centered quality of life and neurocognitive measures as major outcomes and specifically stratify patients based on mutational marker status, disease burden, and symptom acuity.

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The oxidation of Sn(II) to the more stable Sn(IV) degrades the photovoltaic perovskite material CsSnI3; however, this problem can be counteracted via alkaline-earth (AE) doping. In this work, the electronic properties of CsSn1-xAExI3, with x = 0 and 0.25, and AE = Mg and Ca, were investigated via Density Functional Theory. It is proven that the synthetic reactions of all these perovskites are thermodynamically viable. Besides, a slight strengthening in the metal-halide bonds is found in the Mg-doped perovskite; consequently, it exhibits the greatest bulk modulus. Nevertheless, the opposite occurrs with the Ca-doped perovskite, which has the smallest bulk modulus due to the weakening of its metal-halide bonds. The calculated bandgaps for CsSnI3, Mg-doped and Ca-doped perovskites are 1.11, 1.32 and 1.55 eV, respectively, remaining remarkably close to the best photovoltaic-performing value for single-junction solar cells of 1.34 eV. Nevertheless, an indirect bandgap was predicted under Mg-doping. These results support the possibility of implementing AE-doped perovskites as absorber materials in single-junction solar cells, which can deliver higher output voltages than that using CsSnI3. Finally, it was found that Sr or Ba doping could result in semiconductors with bandgaps close to 2.0 eV.

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Rocky Mountain spotted fever (RMSF) is a significant health problem in Sonora, Mexico. The tick vector, Rhipicephalus sanguineus, feeds almost exclusively on domestic dogs that, in this region, also serve as the reservoir for the tick-borne pathogen, Rickettsia rickettsii. A process-based mathematical model of the life cycle of R. sanguineus was developed to predict combinations of insecticidal dog collars and long-lasting insecticidal wall treatments resulting in suppression of indoor tick populations. Because of a high burden of RMSF in a rural community near the Sonora state capital of Hermosillo, a test area was treated with a combination of insecticidal dog collars and long-lasting insecticidal wall treatments from March 2018 to April 2019, with subsequent reduction in RMSF cases and deaths. An estimated 80% of the dogs in the area had collars applied and 15% of the houses were treated. Data on tick abundance on walls and dogs, collected during this intervention, were used to parameterize the model. Model results show a variety of treatment combinations likely to be as successful as the one carried out in the test community.

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In American countries, simultaneously with the coronavirus disease 2019 (COVID-19) pandemic, epidemics caused by different arboviruses (dengue, chikungunya and Zika viruses) are occurring. In Mexico, several of the strategies to control the Aedes aegypti mosquito, which transmits arboviruses, involve the interaction of health personnel with the community. Due to the COVID-19 pandemic, social distancing and home confinement measures have been implemented. To obey these measures and avoid the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission, the National Center for Preventive Programs and Disease Control (CENAPRECE) has presented the vector control strategy in the scenario of simultaneous dengue and COVID-19 transmission in Mexico. In this work, we mention the routine comprehensive mosquito control measures and describe the adaptations that have been made. Furthermore, we discuss the relevance of medical personnel training and supervision, especially focusing on the similarity of symptoms between both pathologies.

En países americanos, simultáneas a la pandemia de enfermedad por coronavirus 2019 (COVID-19) se están dando epidemias ocasionadas por diferentes arbovirus (del dengue, chikunguña y virus del Zika). En México, varias de las estrategias para control del mosquito Aedes aegypti, transmisor de arbovirus, involucran la interacción del personal salubrista y los moradores. Debido a la pandemia de COVID-19 se han implementado medidas de distanciamiento social y resguardo domiciliario. Para respetar estas medidas y evitar riesgo de contagio por coronavirus 2 del síndrome respiratorio agudo grave (SARS-CoV-2), el Centro Nacional de Programas Preventivos y Control de Enfermedades (CENAPRECE) ha presentado la estrategia de control de vectores en el escenario de transmisión simultánea por dengue y COVID-19 en México. En este trabajo mencionamos las medidas habituales de manejo integral de mosquito y mencionamos las adaptaciones realizadas. De igual forma, discutimos la relevancia de la capacitación y la supervisión al personal médico, esto debido a la similitud entre la sintomatología entre ambas patologías.

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Resumen En países americanos, simultáneas a la pandemia de enfermedad por coronavirus 2019 (COVID-19) se están dando epidemias ocasionadas por diferentes arbovirus (del dengue, chikunguña y virus del Zika). En México, varias de las estrategias para control del mosquito Aedes aegypti, transmisor de arbovirus, involucran la interacción del personal salubrista y los moradores. Debido a la pandemia de COVID-19 se han implementado medidas de distanciamiento social y resguardo domiciliario. Para respetar estas medidas y evitar riesgo de contagio por coronavirus 2 del síndrome respiratorio agudo grave (SARS-CoV-2), el Centro Nacional de Programas Preventivos y Control de Enfermedades (CENAPRECE) ha presentado la estrategia de control de vectores en el escenario de transmisión simultánea por dengue y COVID-19 en México. En este trabajo mencionamos las medidas habituales de manejo integral de mosquito y mencionamos las adaptaciones realizadas. De igual forma, discutimos la relevancia de la capacitación y la supervisión al personal médico, esto debido a la similitud entre la sintomatología entre ambas patologías.

Abstract Countries of Latin America are dealing with a simultaneous COVID-19 and vector borne disease (VBDs, Dengue, Zika and Chikungunya) outbreaks. In Mexico, certain activities to control Aedes aegypti mosquito (the main VBDs vector) comprise community participation through the interaction between householders and vector control personnel. Preventive measures against COVID-19 include social distancing and stay-at-home strategy, to obey these policies, and reduce the risk of infection, the National Center for Preventive Programs and Disease Control of Mexico (CENAPRECE) has adapted the vector control approaches in the country. In this paper we mention routine prevention and control activities to control mosquitoes and show the adapted measures. Because, a number of symptoms of the COVID-19 and dengue fever overlap with each other, we also discuss the relevance of accurate disease surveillance and medic’s training and supervision.

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Recently, the need of improvement of energy storage has led to the development of Lithium batteries with porous materials as electrodes. Porous Germanium (pGe) has shown promise for the development of new generation Li-ion batteries due to its excellent electronic, and chemical properties, however, the effect of lithium in its properties has not been studied extensively. In this contribution, the effect of surface and interstitial Li on the electronic properties of pGe was studied using a first-principles density functional theory scheme. The porous structures were modeled by removing columns of atoms in the [001] direction and the surface dangling bonds were passivated with H atoms, and then replaced with Li atoms. Also, the effect of a single interstitial Li in the Ge was analyzed. The transition state and the diffusion barrier of the Li in the Ge structure were studied using a quadratic synchronous transit scheme.

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Intestinal infections represent an important public health concern worldwide. Escherichia coli is one of the main bacterial agents involved in the pathogenesis of different diseases. In 2011, an outbreak of hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS) in Germany was related to a non-O157 STEC strain of O104:H4 serotype. The difficulty in identifying the origin of the bacteria related to the outbreak showed the importance of having epidemiological information from different parts of the world. The aim of this study was to perform a retrospective analysis to determine if E. coli strains isolated from cattle from different locations in Mexico have similar characteristics to those isolated in other countries. Samples obtained in different years from 252 cows belonging to 5 herds were analyzed. A total of 1,260 colonies were selected from the 252 samples, 841 (67%) of which corresponded to E. coli and 419 (33%) to other enterobacteria. In total, 78% (656) of the E. coli strains could be serotyped, of which 393 (59.9%) belonged to 5 diarrheagenic (DEC) pathotypes. Serotyping showed STEC (40.7%) and ETEC (26.7%) strains were more common. PCR assays were used to determine the presence of STEC (eae, stx1, stx2, and ehxA) and EAEC (aatA, aggR, and aapA) genes, and phylogenetic groups. The results showed that 70 strains belonging to 23 serogroups were stx1 and stx2 positive, while 13 strains from the O9 serogroup were ehxA, aggR, and eae positive. Phylogenetic analysis showed 58 (82.9%) strains belonged to A and B1 commensal phylogroups and 12 (17.1%) to B2, D and E virulent phylogroups. An assay to evaluate cross-antigenic reactivity in the serum of cattle between K9 capsular antigen and O104 LPS by ELISA showed similar responses against both antigens (p > 0.05). The antimicrobial sensitivity assay of the strains showed resistance to AM, CEP, CXM, TE, SXT, cephalosporins and fluoroquinolones. The results show that cattle are carriers and potential transmitters of STEC and ETEC strains containing virulence genes. Epidemiological retrospective studies in different countries are of great help for identifying virulent bacterial strains with the potential to cause outbreaks that may have epidemiological impact in susceptible countries.

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In this work, we address the effects of molecular doping on the electronic properties of fluorinated and chlorinated silicon nanowires (SiNWs), in comparison with those corresponding to hydrogen-passivated SiNWs. Adsorption of n-type dopant molecules on hydrogenated and halogenated SiNWs and their chemisorption energies, formation energies, and electronic band gap are studied by using density functional theory calculations. The results show that there are considerable charge transfers and strong covalent interactions between the dopant molecules and the SiNWs. Moreover, the results show that the energy band gap of SiNWs changes due to chemical surface doping and it can be further tuned by surface passivation. We conclude that a molecular based ex-situ doping, where molecules are adsorbed on the surface of the SiNW, can be an alternative path to conventional doping. Graphical abstract Molecular doping of halogenated silicon nanowires.

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The half-metallic behavior of the perovskite Sr2FeMoO6 (SFMO) suggests that this material could be used in spintronic applications. Indeed, SFMO could be an attractive material for multiple applications due to the possibility that its electronic properties could be changed by modifying its spatial confinement or the relative contents of its constituent transition metals. However, there are no reports of theoretical studies on the properties of confined SFMOs with different transition metal contents. In this work, we studied the electronic properties of SFMO slabs using spin-polarized first-principles density functional theory along with the Hubbard-corrected local density approximation and a supercell scheme. We modeled three insulated SFMO slabs with Fe:Mo atomic ratios of 1:1, 1:0, and 0:1; all with free surfaces parallel to the (001) crystal plane. The results show that the half-metallicity of the SFMO is lost upon confinement and the material becomes a conductor, regardless of the ratio of Fe to Mo. It was also observed that the magnetic moment of the slab is strongly influenced by the oxygen atoms. These results could prove useful in attempts to apply SFMOs in fields other than spintronics. Graphical abstract Losing the metallic behaviour: density of states changes, around the Fermi level, due to the Fe/Mo ratio for bidimensional perovskite systems.

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Resumen Introducción La enfermedad de Chagas es endémica en el estado de Morelos. El medicamento disponible es el benznidazol, sin embargo generalmente la adherencia al tratamiento no es vigilado por el personal médico para verificar su cumplimiento. Objetivo Evaluar la adherencia al tratamiento terapéutico y los factores de riesgo asociados con su cumplimiento y el registro de efectos adversos en pacientes con enfermedad de Chagas del estado de Morelos. Material y Métodos Estudio de seguimiento en 20 pacientes asintomáticos. La adherencia se evaluó mediante la aplicación del cuestionario estructurado de Morisky-Green, se aplicó un cuestionario para registrar los factores de riesgo relacionados con el apego al tratamiento, se hicieron visitas domiciliarias y se hicieron entrevistas personalizadas a 8 casos para obtener información sobre factores positivos y negativos asociados al tratamiento. Resultados El 65% de los pacientes fueron adherentes al tratamiento y 35% fueron no adherentes debido a conductas de incumplimiento. Siete casos (35%) presentaron algún tipo de reacción adversa al medicamento que no ameritó la suspensión del tratamiento, excepto dos casos que tuvieron reacciones severas. El análisis estadístico de las variables en los casos adherentes y no adherentes no mostró asociación estadística entre la adherencia y las variables de nivel socioeconómico, escolaridad, acceso al servico médico, estado civil, edad y sexo. Conclusiones. La evaluacion de la adherencia en pacientes con diagnóstico confirmado de enfermedad de Chagas del estado de Morelos, aportó información para dar seguimiento al cumplimiento del tratamiento y registrar los efectos adversos.

Abstract Introduction Chagas disease is endemic in the state of Morelos. The available medication is benznidazole, however adherence to treatment is generally not monitored by medical personnel to verify the accomplishment. Objective To evaluate the adherence to therapeutic treatment and the risk factors associated with its compliance and the registry of adverse effects in patients with Chagas disease in the state of Morelos. Material and Methods Follow-up study in 20 chronic asymptomatic patients. Adherence was assessed using the Morisky-Green structured test, a questionnaire was applied to record the risk factors related to adherence to treatment, home visits were made to the cases, and personalized interviews were conducted in 8 cases to obtain information on positive and negative factors associated with treatment. Results Sixty five percent of patients were adherent to treatment and 35% were non-adherent due to non-compliance behaviors. Seven cases (35%) had some type of adverse reaction to the drug that did not warrant treatment discontinuation, except for two cases that had severe reactions. Statistical analysis of the variables in adherent and non-adherent cases showed no statistical association between adherence and variables of socioeconomic level, school level, access to medical service, marital status, age and sex. Conclusions Adherence assessment in patients with a confirmed diagnosis of Chagas' disease in the state of Morelos provided information to follow up on treatment compliance and record of adverse effects.

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In a previous study, we showed that the Vitalmex Extracorporeal Ventricular Assist Device-Pneumatic (EVAD-P)-a low-cost, pneumatically actuated, pulsatile blood pump-is easy to implant and safe for short-term in vivo support (30 ± 5 days). In the current study, we included additional 30 day experiments and assessed the safety and durability of the EVAD-P for up to 90 days of support. Using the same surgical procedure as in the previous study, we implanted the device into 14 healthy sheep. Group I subjects (n = 7) were evaluated for up to 30 days, and group II (n = 2) and group III (n = 5) subjects were evaluated for up to 49 and 93 days, respectively. After a system redesign, two of the five sheep in group III reached the scheduled end-point without device-related problems at a fixed beat rate of 56 bpm, a stroke volume (SV) of 58.0 ± 2.3 ml, and a flow of 3.5 ± 0.2 L/min. This study shows that the EVAD-P can provide safe pulsatile mechanical circulatory support (MCS) for up to 93 days. To further confirm that the system can consistently provide MCS for this duration, additional studies are recommended.

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We report the case of a young female patient with a diffuse choroidal hemangioma (DCH) and glaucoma as part of Sturge-Weber syndrome (SWS) and symptomatic retinal detachment that was treated successfully with photodynamic therapy (PDT) and intravitreal bevacizumab (IVB). The patient was treated with a single session of PDT, a 689-nm laser was used to deliver 50J/cm(2) with a maximum spot size of 6400µm, for 166s. IVB was administered 3 days later. The exudative retinal detachment (ERD), macular edema and visual acuity improved one week after treatment. The patient was followed for 18 months with no recurrence of ERD, and her visual acuity was preserved. PDT followed by IVB may be an effective treatment option for visual deterioration due to ERD in patients with DCHs, as are found in SWS.

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The vibrational dispersion relations of porous germanium (pGe) and germanium nanowires (GeNWs) were calculated using the ab initio density functional perturbation theory with a generalized gradient approximation with norm-conserving pseudopotentials. Both pores and nanowires were modeled using the supercell technique. All of the surface dangling bonds were saturated with hydrogen atoms. To address the difference in the confinement between the pores and the nanowires, we calculated the vibrational density of states of the two materials. The results indicate that there is a slight shift in the highest optical mode of the Ge-Ge vibration interval in all of the nanostructures due to the phonon confinement effects. The GeNWs exhibit a reduced phonon confinement compared with the porous Ge due to the mixed Ge-dihydride vibrational modes around the maximum bulk Ge optical mode of approximately 300 cm⁻¹; however, the general effects of such confinements could still be noticed, such as the shift to lower frequencies of the highest optical mode belonging to the Ge vibrations.

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The electronic band structure and electronic density of states of cubic SiC nanowires (SiCNWs) in the directions [001], [111], and [112] were studied by means of Density Functional Theory (DFT) based on the generalized gradient approximation and the supercell technique. The surface dangling bonds were passivated using hydrogen (H) atoms and OH radicals in order to study the effects of this passivation on the electronic states of the SiCNWs. The calculations show a clear dependence of the electronic properties of the SiCNWs on the quantum confinement, orientation, and chemical passivation of the surface. In general, surface passivation with either H or OH radicals removes the dangling bond states from the band gap, and OH saturation appears to produce a smaller band gap than H passivation. An analysis of the atom-resolved density of states showed that there is substantial charge transfer between the Si and O atoms in the OH-terminated case, which reduces the band gap compared to the H-terminated case, in which charge transfer mainly occurs between the Si and C atoms.

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A computational study of the dependence of the electronic band structure and density of states on the chemical surface passivation of cubic porous silicon carbide (pSiC) was performed using ab initio density functional theory and the supercell method. The effects of the porosity and the surface chemistry composition on the energetic stability of pSiC were also investigated. The porous structures were modeled by removing atoms in the [001] direction to produce two different surface chemistries: one fully composed of silicon atoms and one composed of only carbon atoms. The changes in the electronic states of the porous structures as a function of the oxygen (O) content at the surface were studied. Specifically, the oxygen content was increased by replacing pairs of hydrogen (H) atoms on the pore surface with O atoms attached to the surface via either a double bond (X = O) or a bridge bond (X-O-X, X = Si or C). The calculations show that for the fully H-passivated surfaces, the forbidden energy band is larger for the C-rich phase than for the Si-rich phase. For the partially oxygenated Si-rich surfaces, the band gap behavior depends on the O bond type. The energy gap increases as the number of O atoms increases in the supercell if the O atoms are bridge-bonded, whereas the band gap energy does not exhibit a clear trend if O is double-bonded to the surface. In all cases, the gradual oxygenation decreases the band gap of the C-rich surface due to the presence of trap-like states.

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OBJECTIVE: To determine the relative importance of Aedes aegyti breeding sites for potential targeted dengue control interventions in Morelos. MATERIAL AND METHODS: Cross-sectional entomological surveys were conducted and collection of Ae. aegypti pupae was taken from all water-holding containers in Cuautla, Jojutla and Tlaquiltenango during dry (1,713 households) and rainy (1,677) seasons in 2008. Relative importance of different types of breeding sites was determined by the contribution (%) to total pupae production within each locality. RESULTS: In Cuautla most pupae during the dry season were found in wash basins (48.5%), tanks and buckets/pots (15% each); during the rainy season, diverse small items (21.3%), buckets/pots (19.3%) and plant pots (12.9%) were more productive. In Jojutla and Tlaquiltenango, 97% of all pupae was found in plant pots during the dry season; during the rainy season diverse small items (26.3%), washing/cooking utensils (13.9%), buckets/pots (12.9%) and plant pots (12.7%) were significant. CONCLUSION: Prevention and control of the dengue vector should be based on this kind of evidence to target the most productive breeding-sites.

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