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Benzo(b)fluoranthene (BbF) is a polycyclic aromatic hydrocarbon (PAH) with five fused benzene rings; it is a highly recalcitrant compound and a priority environmental pollutant due to its detrimental effects on human health and the survival of wild animals. Biodegradation of BbF by microorganisms is an attractive alternative, and few studies have been focused on this issue. In this work, bacteria with the ability to degrade BbF were isolated and selected. The capability of the isolates to tolerate concentrations of 50 and 75 mg l-1 of BbF in liquid medium was evaluated. The selected isolates were identified by the 16S rRNA gene sequencing as belonging to Bacillus, Gordonia, Pseudomonas, Rhodococcus, Ochrobactrum, and Amycolatopsis. All isolates were tolerant and grew at the BbF concentrations tested, some isolates were more competitive than others, and the most prominent was Amycolatopsis sp. Ver12, which removed 47% of BbF, furthermore, with the addition of yeast extract, removed 59% of the compound. In summary, the report shows that Amycolatopsis sp. Ver12 can degrade BbF efficiently and could be considered for bioremediation of BbF-contaminated environments.

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BACKGROUND: Elaborate an updated guideline of recommendations for the safe return to elective orthopedic surgery post COVID-19 pandemic. METHODS: Bibliographic review of relevant global literature. RESULTS: Recommendation guidelines with appropriate definitions of orthopedic elective surgery, correct contagion risk stratification for COVID-19, considerations for specific risk groups, hospital adaptations and anesthetic, intraoperative and postoperative special care for a safe restart of orthopedic elective surgery post COVID-19 pandemic. CONCLUSIONS: The safe restart of orthopedic elective surgery is possible as long as we take into consideration the appropriate recommendations, which we have summarized in this review.

JUSTIFICACIÓN: Proporcionar recomendaciones actuales que nos permitan retomar la cirugía ortopédica electiva posterior a la pandemia COVID-19 en condiciones adecuadas de seguridad para el personal de salud, pacientes y familiares para el tratamiento perioperatorio de acuerdo a la situación en nuestro país. MÉTODOS: Revisión bibliográfica de literatura actual mundial relevante. RESULTADOS: Una guía de recomendaciones con la adecuada definición de procedimientos ortopédicos electivos, la correcta estratificación de riesgo de contagio por COVID-19, las consideraciones especiales en selección de pacientes según su grupo de riesgo, las adecuaciones hospitalarias a implementar y los cuidados anestésicos, intraoperatorios y postoperatorios especiales ante el reinicio de cirugía electiva posterior a la pandemia COVID-19. CONCLUSIONES: El reinicio seguro de cirugía ortopédica electiva posterior a la pandemia COVID-19 en México es posible tomando en cuenta las recomendaciones especiales preoperatorias, intraoperatorias y postoperatorias.

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This work studied the phonon confinement effects at the low temperature specific heat of Si nanowires from first principles using density functional perturbation theory. The nanowires were modeled in the [0 0 1] direction for three different diameters, with the largest cross section being approximately 10 Å. The results indicate the specific heat can be described at low temperatures using a third-grade polynomial of the form c v = λT + ßT 2 + γT3, where the coefficients of quadratic and cubic terms are almost nonexistent for small diameters. These terms begin to have relevance at larger diameters. Further analysis shows λ > ß > γ, which shows the phonon confinement (λ) and surface atoms (ß) become more important than the volumetric contribution (γ) for ultrathin nanowires at low temperatures.

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Theoretical studies on the effect of Li on the electronic properties of porous silicon are still scarce; these studies could help us in the development of Li-ion batteries of this material which overcomes some limitations that bulk silicon has. In this work, the effect of interstitial and surface Li on the electronic properties of porous Si is studied using the first-principles density functional theory approach and the generalised gradient approximation. The pores are modeled by removing columns of atoms of an otherwise perfect Si crystal, dangling bonds of all surfaces are passivated with H atoms, and then Li is inserted on interstitial positions on the pore wall and compared with the replacement of H atoms with Li. The results show that the interstitial Li creates effects similar to n-type doping where the Fermi level is shifted towards the conduction band with band crossings of the said level thus acquiring metallic characteristics. The surface Li introduces trap-like states in the electronic band structures which increase as the number of Li atom increases with a tendency to become metallic. These results could be important for the application of porous Si nanostructures in Li-ion batteries technology.

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Fertility traits, such as heifer pregnancy, are economically important in cattle production systems, and are therefore, used in genetic selection programs. The aim of this study was to identify single nucleotide polymorphisms (SNPs) using RNA-sequencing (RNA-Seq) data from ovary, uterus, endometrium, pituitary gland, hypothalamus, liver, longissimus dorsi muscle, and adipose tissue in 62 candidate genes associated with heifer puberty in cattle. RNA-Seq reads were assembled to the bovine reference genome (UMD 3.1.1) and analyzed in five cattle breeds; Brangus, Brahman, Nellore, Angus, and Holstein. Two approaches used the Brangus data for SNP discovery 1) pooling all samples, and 2) within each individual sample. These approaches revealed 1157 SNPs. These were compared with those identified in the pooled samples of the other breeds. Overall, 172 SNPs within 13 genes (CPNE5, FAM19A4, FOXN4, KLF1, LOC777593, MGC157266, NEBL, NRXN3, PEPT-1, PPP3CA, SCG5, TSG101, and TSHR) were concordant in the five breeds. Using Ensembl's Variant Effector Predictor, we determined that 12% of SNPs were in exons (71% synonymous, 29% nonsynonymous), 1% were in untranslated regions (UTRs), 86% were in introns, and 1% were in intergenic regions. Since these SNPs were discovered in RNA, the variants were predicted to be within exons or UTRs. Overall, 160 novel transcripts in 42 candidate genes and five novel genes overlapping five candidate genes were observed. In conclusion, 1157 SNPs were identified in 62 candidate genes associated with puberty in Brangus cattle, of which, 172 were concordant in the five cattle breeds. Novel transcripts and genes were also identified.

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Resumen: Las lesiones del ligamento cruzado anterior (LCA) hoy en día son tratadas principalmente con injerto de isquiotibiales y una amplia gama de técnicas y sistemas de fijación del LCA en busca de una menor morbilidad del paciente. Se reporta un caso de una paciente de 42 años que sufrió ruptura de LCA, tratada con reconstrucción de LCA con injerto autólogo de isquiotibiales, fijación femoral con pines transversos bioabsorbibles y fijación tibial con tornillo bioabsorbible. La paciente evolucionó con presencia de dolor en región lateral de rodilla, diagnosticado como síndrome de fricción de la banda iliotibial un año posterior a la cirugía. Se realizaron estudios de imagen que incluyeron rayos X y resonancia magnética (RM) donde se observó adecuada fijación del LCA con presencia de migración y ruptura del pin proximal bioabsorbible. Se decidió extraer el fragmento del pin bioabsrobile en un segundo tiempo quirúrgico y la paciente regresó a sus actividades cotidianas y deportivas sin dolor y con una adecuada estabilidad.

Abstract: Injuries of the anterior cruciate ligament are currently treated primarily with the use of hamstring graft with a wide range of different techniques and fixation systems for anterior cruciate ligament in reducing patient morbidity. We report the case of a female patient aged 42 that suffered an anterior cruciate ligament rupture and was treated with anterior cruciate ligament reconstruction with hamstring autograft with femoral fixation with bio-absorbable cross-pin and tibial fixation with bio-absorbable screw. The patient presented lateral knee pain that was diagnosed one year after the operation as an iliotibial band friction syndrome. Imaging studies were performed. X-rays and magnetic resonance imaging demonstrated adequate fixation of the anterior cruciate ligament with the presence of migration and rupture of the proximal bio-absorbable cross-pin. It was decided to remove the bio-absorbable cross-pin fragment in a second surgical procedure after which the patient went back to her daily activities and sports without pain and with stability stable knee.

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Polybrominated diphenyl ethers (PBDEs) are widely distributed compounds in all types of matrices. In the northern portion of the Southern California Bight (SCB), there were reports of some of the largest PBDE concentrations in marine mammals and mussels. Because of this, we decided to analyze the status of PBDEs in the southern part of the SCB. An analysis of 91 samples of marine surface sediment was carried out. All of the 91 samples contained measurable amounts of PBDEs, which is a manifestation of the widespread distribution of these chemical substances. However, the levels detected are between one and two orders of magnitude smaller than those reported in southern California. Currents appear to control the distribution of PBDEs along the coast and the sedimentation sites with largest concentrations are favored by local bathymetry. Maximum concentrations were located in the middle and deeper platforms ranging from 0.02 to 5.90 (with a median 0.71) ng·g(-1) d.w. Deca-BDE mixture is largely predominant in the sediments followed by the penta-BDE mixture. The mass balance for the latitudinal strata shows the largest concentrations in the north where the largest population centers are present and with a very clear southward gradient. The mass balance calculation values showed about 36kg of PBDEs for the north, 22kg for the center, and 10kg for the south strata. In terms of depth, the PBDEs are mainly located on the middle and deep platforms rather than near point discharges, which is different than that reported by other authors.

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Injuries of the anterior cruciate ligament are currently treated primarily with the use of hamstring graft with a wide range of different techniques and fixation systems for anterior cruciate ligament in reducing patient morbidity. We report the case of a female patient aged 42 that suffered an anterior cruciate ligament rupture and was treated with anterior cruciate ligament reconstruction with hamstring autograft with femoral fixation with bio-absorbable cross-pin and tibial fixation with bio-absorbable screw. The patient presented lateral knee pain that was diagnosed one year after the operation as an iliotibial band friction syndrome. Imaging studies were performed. X-rays and magnetic resonance imaging demonstrated adequate fixation of the anterior cruciate ligament with the presence of migration and rupture of the proximal bio-absorbable cross-pin. It was decided to remove the bio-absorbable cross-pin fragment in a second surgical procedure after which the patient went back to her daily activities and sports without pain and with stability stable knee.

Las lesiones del ligamento cruzado anterior (LCA) hoy en día son tratadas principalmente con injerto de isquiotibiales y una amplia gama de técnicas y sistemas de fijación del LCA en busca de una menor morbilidad del paciente. Se reporta un caso de una paciente de 42 años que sufrió ruptura de LCA, tratada con reconstrucción de LCA con injerto autólogo de isquiotibiales, fijación femoral con pines transversos bioabsorbibles y fijación tibial con tornillo bioabsorbible. La paciente evolucionó con presencia de dolor en región lateral de rodilla, diagnosticado como síndrome de fricción de la banda iliotibial un año posterior a la cirugía. Se realizaron estudios de imagen que incluyeron rayos X y resonancia magnética (RM) donde se observó adecuada fijación del LCA con presencia de migración y ruptura del pin proximal bioabsorbible. Se decidió extraer el fragmento del pin bioabsrobile en un segundo tiempo quirúrgico y la paciente regresó a sus actividades cotidianas y deportivas sin dolor y con una adecuada estabilidad.

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Cotton production in the Mexicali valley is adversely affected by wilt and root rot disease associated with Fusarium species. In the present study, we sought to isolate and identify the Fusarium species in the rhizosphere of transgenic insect-resistant cotton plants grown in the Mexicali valley. Our analyses isolated four native fungi from the rhizosphere of cotton plants, namely, T-ICA01, T-ICA03, T-ICA04, and T-ICA08. These fungal isolates were categorized as belonging to Fusarium solani using their phenotypic characteristics and ITS region sequence data. Examination of the infection index showed that T-ICA03 and T-ICA04 caused systemic colonization (90%) of seeds followed by the occurrence of radicle and coleoptile decay. In contrast, T-ICA08 strain was less pathogenic against seed tissues (40%) in comparison to the other strains isolated. Our study showed that in transgenic insect-resistant cotton the disease "Fusarium wilt" is caused by the fungus, F. solani. Future studies are necessary to characterize the F. solani populations to determine whether phenological stages might influence the genetic diversity of the fungal populations present.

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La artroplastía total de cadera es un procedimiento frecuente cuya duración habitual es mayor a 90 minutos y se asocia con una pérdida considerable de sangre. Se realiza generalmente en pacientes > 60 años que presentan comorbilidades. El conocer los factores asociados con el sangrado mayor en los pacientes sometidos a este procedimiento permitirá identificar a aquellos pacientes que se encuentran en riesgo. Material y métodos: Se realizó un estudio retrospectivo, de acuerdo con un modelo de casos y controles seleccionando a los pacientes por su desenlace primario: sangrado mayor/no sangrado mayor. Se incluyeron 142 pacientes tratados con una artroplastía total de cadera, divididos en 47 casos y 95 controles. Resultados: Las variables que presentaron mayor asociación a influir en la presencia de sangrado mayor fue la hemoglobina y hematocrito prequirúrgicos, el IMC, el tiempo quirúrgico así como el uso de transfusión sanguínea aumentaba el tiempo de estancia intrahospitalaria. El valor prequirúrgico de hemoglobina demostró que el tipo de paciente más asociado con sangrado mayor contaba con una hemoglobina > 13 g/dl. Observamos que los 102 pacientes (71.8%) a los que se les realizó una transfusión sanguínea, tuvieron una mayor estancia intrahospitalaria (p 0.007). Conclusión: La presencia de un sangrado mayor es un evento frecuente. Conociendo los factores asociados a sangrado mayor, el equipo quirúrgico se puede anticipar a este evento y en lo posible modificarlo.

Total hip arthroplasty is a common procedure whose typical duration is greater than 90 minutes and is associated with substantial blood loss. It is usually performed in patients > 60 years who have comorbidities. Knowing the factors associated with major bleeding in patients undergoing this procedure will allow us to identify patients who are at risk. Material and methods: We performed a retrospective study, according to a case-control model selecting patients for the primary outcome: major bleeding/not major bleeding. We included 142 patients treated with total hip arthroplasty, divided into 47 cases and 95 matched controls. Results: The variables that showed a higher association to influence the presence of major bleeding was preoperative hemoglobin and hematocrit, BMI, operating time, as well as the use of blood transfusion increased the time of hospital stay. The preoperative hemoglobin value showed that the type of patient more associated with major bleeding had a hemoglobin > 13 g/dl. We observed that 102 patients (71.8%) who underwent a blood transfusion had an increased length of stay (p 0.007). Conclusion: The presence of major bleeding is a frequent event. When knowing the factors associated with major bleeding, the surgical team can anticipate this event and modify it as possible.

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