Evaluation of Amycolaptosis sp. Ver12 as a potential degrader of benzo(b)fluoranthene.

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.

Effect of high-pressure treatment and storage temperature on top-quality (Montanera) Iberian dry-cured pork sausages (chorizo).

The stability after hydrostatic high pressure (HHP) (600 MPa/8 min/10 °C) and 180 days of storage at 4 and 20 °C was evaluated on Iberian dry-cured pork sausages (chorizo) packaged sliced or as half-pieces from pigs raised outdoors. Microbiological, physical-chemical, oxidative, and sensory changes were analyzed. The evolution of mesophilic aerobic and molds and yeasts counts was different in the half and sliced packaged pork sausages after processing and during storage. Sliced and half-packaged pork sausages had instrumental color stability after HHP and during storage. TBA-RS values were quite stable in both products. Protein oxidation values of pork sausage in half-products were increased by at 20 °C. In sliced pork sausage, both HPP and 20 °C storage favored the development of protein oxidation at the end of storage. In the sensory analysis, the sliced product developed more rancidity than the half-pieces during the storage. Therefore, the storage temperature has great importance for the preservation of dry-cured pork sausages, the increases of protein oxidation, and rancidity could reduce the shelf-life at these conditions. The presentation of the product is also relevant when HHP is applied, and this would also compromise the stability of the product when it is stored at room temperature. PRACTICAL APPLICATION: Chorizo is a traditional dry-fermented pork sausage that is generally considered to be microbiologically safe. However, the initial contamination of the raw materials, and some processes, such as the slicing or packaging, can compromise the safety of these products. Additionally, packaged dry-cured sausages require long shelf-life, and although they are normally stored at refrigeration temperature; sometimes, they are preserved at room temperature. The application of hydrostatic high pressure could increase the safety of dry-cured meat products even when they are stored at room temperature. Initial characteristics of each type of pork sausage could determine their technological behavior during processing or during storage under different conditions.

Broadband tuning of polarization modulation instability in microstructured optical fibers.

The wideband tuning of strong bands generated through polarization modulation instability (PMI) in microstructured optical fibers (MOFs) is reported. Tunability is achieved by exploiting the dependence of the phase-matching condition on the fiber's chromatic dispersion and birefringence, which is particularly sensitive when the fiber is pumped near the zero-dispersion wavelength. MOFs designed to accomplish PMI phase-matching when they are infiltrated with ethanol and pumped at 1064 nm were designed and fabricated. Taking advantage of the large thermo-optic coefficient of ethanol, both chromatic dispersion and birefringence were varied through temperature. Wavelength shifts from 937 nm to 863 nm (anti-Stokes) and from 1231 nm to 1387 nm (Stokes) are demonstrated. Such a tuning range corresponds to a frequency shift between the pump and a PMI sideband ranging from 1274cm-1 to 2189cm-1.

[Guidelines for restarting elective orthopaedic surgery post Covid-19 in Mexico]. / Recomendaciones para el reinicio de cirugía ortopédica electiva post-COVID-19 en México.

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.

Genetic mechanisms regulating the host response during mastitis.

Mastitis is a very costly and common disease in the dairy industry. The study of the transcriptome from healthy and mastitic milk somatic cell samples using RNA-Sequencing technology can provide measurements of transcript levels associated with the immune response to the infection. The objective of this study was to characterize the Holstein milk somatic cell transcriptome from 6 cows to determine host response to intramammary infections. RNA-Sequencing was performed on 2 samples from each cow from 2 separate quarters, one classified as healthy (n = 6) and one as mastitic (n = 6). In total, 449 genes were differentially expressed between the healthy and mastitic quarters (false discovery rate <0.05, fold change >±2). Among the differentially expressed genes, the most expressed genes based on reads per kilobase per million mapped reads (RPKM) in the healthy group were associated with milk components (CSN2 and CSN3), and in the mastitic group they were associated with immunity (B2M and CD74). In silico functional analysis was performed using the list of 449 differentially expressed genes, which identified 36 significantly enriched metabolic pathways (false discovery rate <0.01), some of which were associated with the immune system, such as cytokine-cytokine interaction and cell adhesion molecules. Seven functional candidate genes were selected, based on the criteria of being highly differentially expressed between healthy and mastitic groups and significantly enriched in metabolic pathways that are relevant to the inflammatory process (GLYCAM1, B2M, CD74, BoLA-DRA, FCER1G, SDS, and NFKBIA). Last, we identified the differentially expressed genes that are located in quantitative trait locus regions previously known to be associated with mastitis, specifically clinical mastitis, somatic cell count, and somatic cell score. It was concluded that multiple genes within quantitative trait locus regions could potentially affect host response to mastitis-causing agents, making some cows more susceptible to intramammary infections. The identification of potential candidate genes with functional, statistical, biological, and positional relevance associated with host defense to infection will contribute to a better understanding of the underlying genetic architecture associated with mastitis. This in turn will improve the sustainability of agricultural practices by facilitating the selection of cows with improved host defense leading to increased resistance to mastitis.

Confinement effect on the low temperature specific heat for ultrathin silicon nanowires: a first principles study.

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.

Pre- and post-puberty expression of genes and proteins in the uterus of Bos indicus heifers: the luteal phase effect post-puberty.

Progesterone signaling and uterine function are crucial in terms of pregnancy establishment. To investigate how the uterine tissue and its secretion changes in relation to puberty, we sampled tissue and uterine fluid from six pre- and six post-pubertal Brahman heifers. Post-pubertal heifers were sampled in the luteal phase. Gene expression of the uterine tissue was investigated with RNA-sequencing, whereas the uterine fluid was used for protein profiling with mass spectrometry. A total of 4034 genes were differentially expressed (DE) at a nominal P-value of 0.05, and 26 genes were significantly DE after Bonferroni correction (P < 3.1 × 10-6 ). We also identified 79 proteins (out of 230 proteins) that were DE (P < 1 × 10-5 ) in the uterine fluid. When we compared proteomics and transcriptome results, four DE proteins were identified as being encoded by DE genes: OVGP1, GRP, CAP1 and HBA. Except for CAP1, the other three had lower expression post-puberty. The function of these four genes hypothetically related to preparation of the uterus for a potential pregnancy is discussed in the context of puberty. All DE genes and proteins were also used in pathway and ontology enrichment analyses to investigate overall function. The DE genes were enriched for terms related to ribosomal activity. Transcription factors that were deemed key regulators of DE genes are also reported. Transcription factors ZNF567, ZNF775, RELA, PIAS2, LHX4, SOX2, MEF2C, ZNF354C, HMG20A, TCF7L2, ZNF420, HIC1, GTF3A and two novel genes had the highest regulatory impact factor scores. These data can help to understand how puberty influences uterine function.

Lithium effect on the electronic properties of porous silicon for energy storage applications: a DFT study.

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.

Carbon monoxide sensing properties of B-, Al- and Ga-doped Si nanowires.

Silicon nanowires (SiNWs) are considered as potential chemical sensors due to their large surface-to-volume ratio and their possible integration into arrays for nanotechnological applications. Detection of harmful gases like CO has been experimentally demonstrated, however, the influence of doping on the sensing capacity of SiNWs has not yet been reported. For this work, we theoretically studied the surface adsorption of a CO molecule on hydrogen-passivated SiNWs grown along the [111] crystallographic direction and compared it with the adsorption of other molecules such as NO, and O2. Three nanowire diameters and three dopant elements (B, Al and Ga) were considered, and calculations were done within the density functional theory framework. The results indicate that CO molecules are more strongly adsorbed on the doped SiNW than on the pristine SiNW. The following trend was observed for the CO adsorption energies: E A[B-doped] > E A[Al-doped] > E A[Ga-doped] > E A[undoped], for all diameters. The electronic charge transfers between the SiNWs and the adsorbed CO were estimated by using a Voronoi population analysis. The CO adsorbed onto the undoped SiNWs has an electron-acceptor character, while the CO adsorbed onto the B-, Al-, and Ga-doped SiNWs exhibits an electron-donor character. Comparing these results with the ones obtained for the NO and O2 adsorption, the larger CO adsorption energy on B-doped SiNWs indicates their good selectivity towards CO. These results suggest that SiNW-based sensors of toxic gases could represent a clear and advantageous application of nanotechnology in the improvement of human quality of life.

Global differential gene expression in the pituitary gland and the ovaries of pre- and postpubertal Brahman heifers.

To understand genes, pathways, and networks related to puberty, we characterized the transcriptome of two tissues: the pituitary gland and ovaries. Samples were harvested from pre- and postpubertal Brahman heifers (same age group). Brahman heifers () are older at puberty compared with , a productivity issue. With RNA sequencing, we identified differentially expressed (DEx) genes and important transcription factors (TF) and predicted coexpression networks. The number of DEx genes detected in the pituitary gland was 284 ( < 0.05), and was the most DEx gene (fold change = 4.12, = 0.01). The gene promotes bone mineralization through transforming growth factor-ß (TGFß) signaling. Further studies of the link between bone mineralization and puberty could target . In ovaries, 3,871 genes were DEx ( < 0.05). Four highly DEx genes were noteworthy for their function: (a γ-aminobutyric acid [GABA] transporter), (), and () and its receptor . These genes had higher ovarian expression in postpubertal heifers. The GABA and its receptors and transporters were expressed in the ovaries of many mammals, suggesting a role for this pathway beyond the brain. The pathway has been known to influence the timing of puberty in rats, via modulation of GnRH. The effects of at the hypothalamus, pituitary gland, and ovaries have been documented. and its receptors are known factors in the release of GnRH, similar to and GABA, although their roles in ovarian tissue are less clear. Pathways previously related to puberty such as TGFß signaling ( = 6.71 × 10), Wnt signaling ( = 4.1 × 10), and peroxisome proliferator-activated receptor (PPAR) signaling ( = 4.84 × 10) were enriched in our data set. Seven genes were identified as key TF in both tissues: , , , , , , and a novel gene. An ovarian subnetwork created with TF and significant ovarian DEx genes revealed five zinc fingers as regulators: , , , , and . Recent work of hypothalamic gene expression also pointed to zinc fingers as TF for bovine puberty. Although some zinc fingers may be ubiquitously expressed, the identification of DEx genes in common across tissues points to key regulators of puberty. The hypothalamus and pituitary gland had eight DEx genes in common. The hypothalamus and ovaries had 89 DEx genes in common. The pituitary gland and ovaries had 48 DEx genes in common. Our study confirmed the complexity of puberty and suggested further investigation on genes that code zinc fingers.

SNP detection using RNA-sequences of candidate genes associated with puberty in cattle.

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.

Síndrome de fricción de la cintilla iliotibial posterior a reconstrucción del ligamento cruzado anterior con pines transversos bioabsorbibles / Iliotibial band friction syndrome due to bioabsorbable pins in ACL reconstruction

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.

Transcriptome analyses identify five transcription factors differentially expressed in the hypothalamus of post- versus prepubertal Brahman heifers.

Puberty onset is a developmental process influenced by genetic determinants, environment, and nutrition. Mutations and regulatory gene networks constitute the molecular basis for the genetic determinants of puberty onset. The emerging knowledge of these genetic determinants presents opportunities for innovation in the breeding of early pubertal cattle. This paper presents new data on hypothalamic gene expression related to puberty in (Brahman) in age- and weight-matched heifers. Six postpubertal heifers were compared with 6 prepubertal heifers using whole-genome RNA sequencing methodology for quantification of global gene expression in the hypothalamus. Five transcription factors (TF) with potential regulatory roles in the hypothalamus were identified in this experiment: , , , , and . These TF genes were significantly differentially expressed in the hypothalamus of postpubertal versus prepubertal heifers and were also identified as significant according to the applied regulatory impact factor metric ( < 0.05). Two of these 5 TF, and , were zinc fingers, belonging to a gene family previously reported to have a central regulatory role in mammalian puberty. The gene belongs to the family of homologues of Drosophila sine oculis () genes implicated in transcriptional regulation of gonadotrope gene expression. Tumor-related genes such as and are known to affect basic cellular processes that are relevant in both cancer and developmental processes. Mutations in were associated with puberty in humans. Mutations in these TF, together with other genetic determinants previously discovered, could be used in genomic selection to predict the genetic merit of cattle (i.e., the likelihood of the offspring presenting earlier than average puberty for Brahman). Knowledge of key mutations involved in genetic traits is an advantage for genomic prediction because it can increase its accuracy.

On the sources of PBDEs in coastal marine sediments off Baja California, Mexico.

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.

[Iliotibial band friction syndrome due to bioabsorbable pins in ACL reconstruction]. / Síndrome de fricción de la cintilla iliotibial posterior a reconstrucción del ligamento cruzado anterior con pines transversos bioabsorbibles.

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.

Molecular identification of Fusarium species isolated from transgenic insect-resistant cotton plants in Mexicali valley, Baja California.

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.

Factores asociados a un sangrado mayor en reemplazo total de cadera / Associated factors due to major bleeding in total hip replacement

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.

Transition of pattern generation: the phenomenon of post-scratching locomotion.

A fundamental problem in neurophysiology is the understanding of neuronal mechanisms by which the central nervous system produces a sequence of voluntary or involuntary motor acts from a diverse repertory of movements. These kinds of transitions between motor acts are extremely complex; however, they could be analyzed in a more simple form in decerebrate animals in the context of spinal central pattern generation. Here, we present for the first time a physiological phenomenon of post-scratching locomotion in which decerebrate cats exhibit a compulsory locomotor activity after an episode of scratching. We found flexor, extensor and intermediate single interneurons rhythmically firing in the same phase during both scratching and the subsequent post-scratching locomotion. Because no changes in phase of these neurons from scratching to post-scratching locomotion were found, we suggest that in the lumbar spinal cord there are neurons associated with both motor tasks. Moreover, because of its high reproducibility we suggest that the study of post-scratching fictive locomotion, together with the unitary recording of neurons, could become a useful tool to study neuronal mechanisms underlying transitions from one rhythmic motor task to another, and to study in more detail the central pattern generator circuitry in the spinal cord.

[Associated factors due to major bleeding in total hip replacement]. / Factores asociados a un sangrado mayor en reemplazo total de cadera.

MATERIAL AND METHODS: 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. 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.

MATERIAL Y MÉTODOS: 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. 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.

Artroplastía unicompartimental medial de rodilla con prótesis Oxford fase 3: Resultados con seguimiento de 2 a 11 años / Medial unicompartmental knee arthroplasty with a phase 3 Oxford prosthesis: Results with a 2 to 11 year follow-up

Introducción: En los últimos años se ha visto un amplio interés renovado en la artroplastía unicompartimental como resolución de la artrosis medial de rodilla debido a las ventajas sobre la prótesis total de rodilla. Métodos: Se realizó un estudio epidemiológico retrospectivo en el cual se estudiaron 25 pacientes consecutivos (30 rodillas) de Enero de 2002 a Septiembre de 2013, sometidos a artroplastía unicompartimental de rodilla con prótesis Oxford fase 3 con el uso de insertos de polietileno con diseño ultracongruente. Con un promedio de seguimiento de 6.1 años (1.1-11.5 años). Se analizaron variables demográficas como peso, talla e índice de masa corporal y variables perioperatorias como valores de hemoglobina, sangrado y tiempo quirúrgico; evaluamos la función pre- y postoperatoria de los pacientes de acuerdo a escalas clínicas y funcionales. Realizamos una evaluación clínica y radiológica del implante revisando la presencia de cambios artrósicos en los compartimentos no intervenidos. Resultados: Se observó una óptima sobrevida del implante. El Knee Score Society clínico mejoró de 61 en el preoperatorio a 84 al momento final del seguimiento obteniendo un 90% de resultados excelentes y buenos. Al final del seguimiento obtuvimos un promedio postquirúrgico de flexión de 120º y con extensión completa. Sólo dos pacientes presentaron resultados satisfactorios por progresión de la artrosis en el compartimento lateral y únicamente un paciente requirió conversión en dos tiempos a prótesis total debido a infección periprotésica. Conclusión: La artroplastía unicompartimental de rodilla es una cirugía menos invasiva con buenos resultados clínicos y funcionales. El éxito del procedimiento se basa en la correcta selección de los pacientes.

Introduction: There has been great renewed interest in the past few years in unicompartmental arthroplasty for medial arthrosis of the knee due to the advantages over total knee replacement. Methods: A retrospective epidemiological study was performed with 25 consecutive patients (30 knees) from January 2002 to September 2013, who underwent unicompartmental knee arthroplasty with a phase 3 Oxford prosthesis using polyethylene inserts with an ultra-congruent design. With an average follow-up of 6.1 years (1.1-11.5 years). The following demographical variables were analyzed: weight, size, body mass index and perioperative variables like hemoglobin, bleeding and surgical time; we evaluated the pre and post-operative function of patients according to clinical and functional scales. We performed a clinical and radiological evaluation of the implant to check for the presence of arthrosis changes in non-intervened compartments. Results: We observed optimal survival of the implant. The clinical Knee Score Society improved from 61 in the pre-op to 84 at the end of the follow-up period, with 90% excellent and good results. At the end of the follow-up the average post-surgical flection was 120º and full extension. Only two patients showed satisfactory results due to progression of the arthrosis in the lateral compartment and only one patient required conversion to total replacement in two surgeries due to a periprosthetic infection. Conclusion: Unicompartmental knee arthroplasty is a less invasive surgery with good clinical and functional results. The success of the procedure is based on the proper selection of patients.