Vision Transformer Customized for Environment Detection and Collision Prediction to Assist the Visually Impaired.

This paper presents a system that utilizes vision transformers and multimodal feedback modules to facilitate navigation and collision avoidance for the visually impaired. By implementing vision transformers, the system achieves accurate object detection, enabling the real-time identification of objects in front of the user. Semantic segmentation and the algorithms developed in this work provide a means to generate a trajectory vector of all identified objects from the vision transformer and to detect objects that are likely to intersect with the user's walking path. Audio and vibrotactile feedback modules are integrated to convey collision warning through multimodal feedback. The dataset used to create the model was captured from both indoor and outdoor settings under different weather conditions at different times across multiple days, resulting in 27,867 photos consisting of 24 different classes. Classification results showed good performance (95% accuracy), supporting the efficacy and reliability of the proposed model. The design and control methods of the multimodal feedback modules for collision warning are also presented, while the experimental validation concerning their usability and efficiency stands as an upcoming endeavor. The demonstrated performance of the vision transformer and the presented algorithms in conjunction with the multimodal feedback modules show promising prospects of its feasibility and applicability for the navigation assistance of individuals with vision impairment.

Efecto del ácido deoxicólico sobre la regulación del transporte iónico intestinal en la rata / Deoxycholic acid efect on intestinal ionic transport regulation in the rat

The intestine has a very important role in the homeostasis of the internal medium. Bile acids play a regulatory role in the digestion and absorption of nutrients. Among them, deoxycholic acid, when its luminal concentration increases due to bacterial overgrowth, modifies hydroelectrolytic transport, producing an increase in the volume of water and electrolytes in stools.

El intestino tiene un papel muy importante en la homeostasis del medio interno. Los ácidos biliares cumplen una función reguladora en la digestión y absorción de nutrientes. Entre ellos el ácido deoxicólico, cuando aumenta su concentración luminal por sobrecrecimiento bacteriano, modifica el transporte hidroelectrolítico produciendo aumento del volumen de agua y electrolitos en las deposiciones.

Prevalence of Poor Bone Quality in Patients Undergoing Spine Surgery: A Comprehensive Approach.

STUDY DESIGN: A cross-sectional study. OBJECTIVES: To investigate the prevalence of poor bone quality in patients requiring spine surgery through comprehensive evaluation with bone mass density (BMD), trabecular bone score (TBS), FRAX, and vitamin D status. METHODS: we prospectively recruited patients of > 50 years old candidates for lumbar or cervical spine fusion surgery at our institution. Recorded data were: demographic, body mass index (BMI), risk factors for osteoporosis, daily calcium intake, FRAX score, disability index for lumbar and cervical spine, and VAS for pain. Serum 25 OH vitamin D, BMD using DXA, and TBS was also evaluated. RESULTS: A total of 104 patients were recruited, osteoporosis by BMD was detected in 9.6%, and osteopenia in 34.6% of patients. 69.4% of patients with osteopenia had a degraded or partially degraded bone microarchitecture by TBS.Low levels of vitamin D were detected in 79.8% of patients. Increased pain was associated with low BMD levels. Adding TBS to BMD for the determination of bone strength resulted in 33.7% of patients with poor bone quality. Lastly, the combination of BMD, TBS, and FRAX revealed 37,5% of patients with poor bone quality. CONCLUSIONS: Poor bone quality and low vitamin D levels are quite common among patients aged ≥ 50 years undergoing spine surgery. DXA alone seems not enough for preoperative identification of impaired bone quality cases. FRAX is useful for identifying high-risk patients and TBS is a valuable complement to DXA by adding the dimension of bone quality.

Mejoramiento nutricional, entorno ambiental y psicomotor en desnutridos crónicos menores con la estrategia clapsen comunitaria / Nutritional and psychomotor improvement of chronically malnourished children with clapsen strategy

OBJETIVO: mejorar el estado nutricional, el desarrollo psicomotor y el entorno en niños preescolares con desnutrición crónica en zonas rurales. MATERIALES Y MÉTODOS: 53 niños ingresaron al estudio de intervención epidemiológica de acuerdo a los criterios de inclusión. Para la evaluación inicial y final se incorporaron las tres dimensiones, por un lado el estado nutricional caracterizado por antropometría, clínica y laboratorio, por otro lado el desarrollo psicomotor a partir de la escala de Denver y por último el entorno ambiental según la escala de porcentajes. El seguimiento se realizó con la estrategia CLAPSEN COMMUNITY que incide en las áreas Clínica, Laboratorio, Antropometría, Psicología, Social, Educación y Nutrición. El proceso fue llevado a cabo por un equipo multidisciplinario, mediante el uso de folletos educativos, charlas, talleres y ferias comunitarias con diversas temáticas. Se introdujo el instrumento de seguimiento de la mochila nutricional. Se desarrollaron huertos familiares, se entregaron suplementos nutricionales y se realizó el manejo del estrés y la estimulación del desarrollo psicomotor del niño. Resultados: Dimensión nutricional: crecimiento al ingreso: -2,11 ± 0,7 DS a: 0,67 ± 0,3 DE (p <0,000) al alta; Hb: 10,4g / dl5 ± 3,3 a: 12,54g / dl ± 1,2 (p> 0,001); Ferritina de: 12,81 ± 9,65mg/ dl a: 19,60 ± 1011mg / l (p <0,003). Desarrollo: las habilidades motoras gruesas mejoraron de 76,1 ± 14 SD a 95,1 ± 5,7 SD (p≤0,000). Coordinación: entrada: 74,2 ± 16 DS, salida: 96,8 ± 12DS (p≤0,000); lenguaje de entrada: 73,7 ± 15 SD. a: 95,67 ± 5 (p≤0,000); ingreso personal-social de 76,515 SD a: 99,07 ± 4DS (p≤0,000), Entorno ambiental inadecuado de 83,37% a: 18.13%. Con correlaciones significativas entre estado nutricional ­ desarrollo psicomotor y entorno. Mientras que los parámetros nutricionales, el desarrollo psicomotor, el entorno de los niños mejoraron, el grado de contaminación del entorno del niño disminuyó. CONCLUSIÓN: la intervención con la estrategia CLAPSEN permitió mejorar el entorno, el estado nutricional y el desarrollo psicomotor de forma relevante(AU)

OBJECTIVE: to improve the nutritional status, psychomotor development and the environment in preschool children with chronic malnutrition in rural areas. MATERIALS AND METHODS: 53 children entered the epidemiological intervention study according to the inclusion criteria. For the initial and final evaluation, the three dimensions were incorporated, on the one hand, there is the nutritional state characterized by anthropometry, clinical and laboratory, on the other hand the psychomotor development from the Denver scale and finally the environmental environment according to the scale of percentages. Follow-up was carried out with the CLAPSEN COMMUNITY strategy that influences the Clinical, Laboratory, Anthropometry, Psychology, Social, Education and Nutrition areas. The process was carried out by a multidisciplinary team, through the use of educational brochures, talks, workshops and community fairs with diverse themes. The nutritional backpack monitoring instrument was introduced. Family gardens were developed, nutritional supplements were provided, and stress management and stimulation of the child's psychomotor development were carried out. RESULTS: nutritional dimension: growth on admission: -2.11 ± 0.7 SD to: 0.67 ± 0.3 SD (p <0.000) at discharge; Hb: 10.4g / dl5 ± 3.3 to: 12.54g / dl ± 1.2 (p> 0.001); Ferritin from: 12.81 ± 9.65mg / dl to: 19.60 ± 1011mg / l (p <0.003). Development: gross motor skills improved from 76.1 ± 14 SD to 95.1 ± 5.7 SD (p≤0.000). Coordination: entry: 74.2 ± 16DS, egress: 96.8 ± 12DS (p≤0.000); entry language: 73.7 ± 15 SD. a: 95.67 ± 5 (p≤0.000); Personal-social income from 76.515 SD to: 99.07 ± 4DS (p≤0.000), Inadequate environmental setting from 83.37% to: 18.13%. With significant correlations between nutritional status - psychomotor development and environment. While the nutritional parameters, psychomotor development, children's environment improved, the degree of contamination of the child's environment decreased. CONCLUSION: the intervention with the CLAPSEN strategy allowed to improve the environment, nutritional status and psychomotor development in a relevant way.(AU)

Atomic-Scale Investigation on the Evolution of Tio2-Anatase Prepared by a Sonochemical Route and Treated with NaOH.

To date, the formation mechanisms of TiO2, as well as its heterostructures, have not been clarified. Moreover, detailed research on the transition from a tetragonal anatase phase to the monoclinic phase of the TiO2(B) phase and their interface structure has been quite limited until now. In the present study, we report on the sonochemical synthesis of TiO2-anatase with a crystallite size of 5.2 ± 1.5 nm under different NaOH concentrations via the hydrothermal method. The use of alkaline solution and the effect of the temperature and reaction time on the formation and structural properties of TiO2-anatase nanopowders were studied. The effects of NaOH concentration on the formation and transformation of titanate structures are subject to thermal effects that stem from the redistribution of energy in the system. These mechanisms could be attributed to three phenomena: (1) the self-assembly of nanofibers and nanosheets, (2) the Ostwald ripening process, and (3) the self-development of hollow TiO2 mesostructures.

Tendencias de actuación de los cirujanos de columna respecto a la osteoporosis / Trends and attitudes of spine surgeons regarding osteoporosis

Antecedentes y objetivos: Con cada vez mayor frecuencia neurocirujanos y otros especialistas nos vemos afrontados al tratamiento de pacientes con osteoporosis que requieren una cirugía de fusión de columna. Pese a existir tratamientos farmacológicos efectivos e innovaciones en las técnicas quirúrgicas que pueden beneficiar a estos pacientes, se han reportado tasas bajas de diagnóstico y tratamiento preoperatorio de osteoporosis, además de una escasa participación de los cirujanos de columna en este ámbito. El objetivo de este estudio fue evaluar las tendencias en el diagnóstico y tratamiento respecto a la osteoporosis en los cirujanos de raquis de la comunidad neuroquirúrgica. Material y métodos: Se realizó una encuesta electrónica con 10 preguntas de opción múltiple a los miembros de la Sociedad Española de Neurocirugía (SENEC). Se valoraron: 1) papel del cirujano de columna frente a la osteoporosis en la artrodesis de raquis, 2) la influencia de osteoporosis en la seudoartrosis y 3) tendencias de tratamiento respecto a las fracturas vertebrales osteoporóticas. Resultados: Obtuvimos un total de 77 cuestionarios respondidos. En los pacientes con sospecha de osteoporosis, un 32,5% de los encuestados no se plantea ninguna medida para diagnosticarla antes de una artrodesis vertebral. En osteoporóticos sin tratamiento, un 37,7% procedería con la cirugía sin tratamiento o lo haría después de la cirugía. El 48% de los respondedores optaría por modificar su estrategia quirúrgica en los pacientes con osteoporosis. La técnica quirúrgica preferida fue la colocación de tornillos cementados (70%). En la seudoartrosis, el 46,1% no considera necesario el diagnóstico de osteoporosis para una reintervención. En las fracturas vertebrales osteoporóticas, el 80,5% de los cirujanos se plantea alguna medida que facilitara el tratamiento de la osteoporosis. Conclusiones: Una mayor participación del cirujano de columna mejoraría el diagnóstico y tratamiento preoperatorio de la osteoporosis en las cirugías de artrodesis vertebral y seudoartrosis. En las fracturas vertebrales existe una mejor concienciación para optimizar el tratamiento y el seguimiento de la osteoporosis

Background and objectives: Neurosurgeons and other specialists are increasingly having to treat patients with osteoporosis who require spinal fusion surgery. Although there are effective pharmacological treatments and innovations in surgical techniques that can benefit these patients, low rates of diagnosis and preoperative treatment of osteoporosis have been reported, in addition to the limited participation of spine surgeons in this area. The objective of this study was to evaluate trends in diagnosis and treatment of osteoporosis with regard to spine surgeons of the neurosurgical community. Material and methods: An electronic survey with 10 multiple-choice questions was issued to Spanish Neurosurgery Society (SENEC) members. The following were evaluated: 1) the surgeon's role regarding osteoporosis in spinal arthrodesis, 2) the influence of osteoporosis in pseudarthrosis, and 3) treatment trends in relation to osteoporotic vertebral fractures. Results: A total of 77 completed questionnaires were obtained. In patients with suspected osteoporosis, 32.5% of respondents did not consider any measure to diagnose it before spinal arthrodesis. In osteoporosis without treatment, 37.7% would proceed with surgery without treatment or would do so after surgery. A total of 48% of respondents would choose to modify their surgical strategy in patients with osteoporosis. The preferred surgical technique was the placement of augmentation screws (70%). In pseudarthrosis, 46.1% did not consider an osteoporosis diagnosis to be necessary for a reoperation. In osteoporotic vertebral fractures, 80.5% of surgeons considered some measure that would facilitate the treatment of osteoporosis. Conclusions: Greater participation of the spine surgeon could improve the diagnosis and preoperative treatment of osteoporosis in spinal arthrodesis surgery and pseudarthrosis. In vertebral fractures, there is greater awareness of the optimisation of treatment and monitoring of osteoporosis

Anatomical, taxonomic, and phylogenetic reappraisal of a poorly known ghost knifefish, Tembeassu marauna (Ostariophysi: Gymnotiformes), using X-ray microcomputed tomography.

A detailed osteological study of the poorly known and critical endangered ghost knifefish, Tembeassu marauna, from the rio Paraná, Brazil, was conducted using X-ray microcomputed tomography (µCT scan). A redescription of the external anatomy was performed, including the unusual presence of a rostral patch of extra teeth on the region of the upper lip anterior to the premaxilla and the prominent anterior fleshy expansions in both upper and lower lips. The newly surveyed characters were included and analyzed in light of a recent morphological data matrix for Gymnotiformes. In spite of some uncertainties that remains as to phylogenetic allocation of the genus, the most probable hypothesis is that Tembeassu is the sister group of a clade that includes Megadontognathus and Apteronotus sensu stricto. The phylogenetic analysis also supports that Tembeassu is considered a valid genus of Apteronotidae. An amended diagnosis for the genus is also provided.

Trends and attitudes of spine surgeons regarding osteoporosis. / Tendencias de actuación de los cirujanos de columna respecto a la osteoporosis.

BACKGROUND AND OBJECTIVES: Neurosurgeons and other specialists are increasingly having to treat patients with osteoporosis who require spinal fusion surgery. Although there are effective pharmacological treatments and innovations in surgical techniques that can benefit these patients, low rates of diagnosis and preoperative treatment of osteoporosis have been reported, in addition to the limited participation of spine surgeons in this area. The objective of this study was to evaluate trends in diagnosis and treatment of osteoporosis with regard to spine surgeons of the neurosurgical community. MATERIAL AND METHODS: An electronic survey with 10 multiple-choice questions was issued to Spanish Neurosurgery Society (SENEC) members. The following were evaluated: 1) the surgeon's role regarding osteoporosis in spinal arthrodesis, 2) the influence of osteoporosis in pseudarthrosis, and 3) treatment trends in relation to osteoporotic vertebral fractures. RESULTS: A total of 77 completed questionnaires were obtained. In patients with suspected osteoporosis, 32.5% of respondents did not consider any measure to diagnose it before spinal arthrodesis. In osteoporosis without treatment, 37.7% would proceed with surgery without treatment or would do so after surgery. A total of 48% of respondents would choose to modify their surgical strategy in patients with osteoporosis. The preferred surgical technique was the placement of augmentation screws (70%). In pseudarthrosis, 46.1% did not consider an osteoporosis diagnosis to be necessary for a reoperation. In osteoporotic vertebral fractures, 80.5% of surgeons considered some measure that would facilitate the treatment of osteoporosis. CONCLUSIONS: Greater participation of the spine surgeon could improve the diagnosis and preoperative treatment of osteoporosis in spinal arthrodesis surgery and pseudarthrosis. In vertebral fractures, there is greater awareness of the optimisation of treatment and monitoring of osteoporosis.

In-Plant Validation Study of Harvest Process Controls in Two Beef Processing Plants in Honduras.

Imported meat in the United States can become a food safety hazard if proper food safety programs are not fully implemented in foreign meat processing plants. Thus, exporting countries' food safety inspection systems must be equivalent to the U.S. federal inspection system to become eligible to export meat to the United States. The objective of this study was to validate the beef harvest Hazard Analysis and Critical Control Points and food safety programs of two beef processing plants in Honduras operating under U.S. equivalency standards by evaluating the presence of Salmonella (plant A) and Shiga toxin-producing Escherichia coli (STEC; plant B) on hides. Additionally, evaluating pathogen transfer from hides to carcasses, as detected by preevisceration sampling, and the mitigation of transferred pathogens, by application of carcass spray interventions and determination of Salmonella presence in lymph nodes, was also conducted. In plant A, the presence of Salmonella on hides ( n = 30 of 687; 4.4%) was significantly greater ( P < 0.10) than on carcasses swabbed at preevisceration ( n = 7 of 687; 1.0%), after intervention ( n = 13 of 678; 1.9%), and in lymph nodes ( n = 14 of 691; 2.0%). In plant B, Salmonella was not detected on hide samples; therefore, data could not be used for validation of the harvest Hazard Analysis and Critical Control Points program. Alternatively, STEC presence on hides ( n = 21 of 85; 24.7%) was greater ( P < 0.10) than on carcasses at preevisceration ( n = 3 of 85; 3.5%) and after intervention ( n = 1 of 85; 1.2%). Pathogen presence in plant B did not differ ( P = 0.306) between carcasses in preevisceration and postintervention stages; both, however, were substantially low. Both plants' controls effectively reduced Salmonella and STEC presence in postintervention carcasses.

A Rare Case of Negative-Pressure Hydrocephalus: A Plausible Explanation and the Role of Transmantle Theory.

BACKGROUND: Negative-pressure hydrocephalus is a rare condition with the development of symptomatic hydrocephalus despite subnormal intracranial pressure (ICP). The etiology remains unclear. Some authors proposed that the differential pressure between the ventricular space and the subarachnoid space over cerebral convexity leads to the development of ventriculomegaly, namely as the transmantle pressure theory. CASE DESCRIPTION: A 49-year-old patient with a left Sylvian fissure arachnoid cyst underwent several surgeries including cystoperitoneal shunts and fenestrations of the cyst. The patient developed a cerebrospinal fluid fistula from the cranial wound was complicated by bacterial meningitis. Consequently, the shunt was removed, and external cyst drainage was placed. After 9 days, the patient developed acute hydrocephalus requiring external ventricular drainage (EVD). Two days later, after overdrainage of the external cyst drain, the patient suffered neurologic deterioration. The ICP measured by the EVD was -4 cm H2O, and a computed tomography scan demonstrated progression of the hydrocephalus. The external cyst drainage was shut off and the EVD level was adjusted to produce between 5 and 10 mL/hour of cerebrospinal fluid under a subatmospheric pressure set at -5 cm H2O, and gradually raised in increments of 1 cm every 3 days until a positive ICP occurred. Once clinical and radiographic stability was accomplished, a programmable ventriculoperitoneal shunt was inserted set to 30 mm H2O. A marked clinical and radiologic improvement was observed in the follow-up. CONCLUSIONS: This negative-pressure hydrocephalus case report supports the main role of the transmantle pressure theory. The subatmospheric EVD method and a low-pressure valve resulted in excellent clinical and radiographic outcomes.

Intervenções de enfermagem frente aos desconfortos/complicações em uma unidade de recuperação pósanestésica / Nursing interventions against discounts/complications in a post-anesthetic recovery unit

Objetivo: identificar na literatura os mais recorrentes desconfortos/complicações pós-anestésicas e as intervenções de enfermagem. Metodologia: trata-se de uma revisão integrativa. As bases utilizadas foram: MEDLINE, LILACS E BDENF por meio da Biblioteca Virtual em Saúde. Os critérios de inclusão foram: artigos publicados nas literaturas científicas, nacional e internacional, disponíveis na íntegra, idiomas: português, inglês ou espanhol, acesso gratuito nas bases de dados selecionadas, sem limite de ano, que respondiam a questão norteadora: "Quais as intervenções de enfermagem frente às complicações/desconfortos em adultos em Sala de Recuperação pós-anestésica?" Resultados: Foram encontrados 1261, dos quais após critérios de inclusão a revisão foi operacionalizada com 09 estudos. A partir da análise crítica dos artigos, as complicações, riscos e intervenções foram identificadas e assim categorizadas: hiper e hipotermia, hipoxemia, hiper e hipotensão, náuseas e vômitos, retenção urinária, sangramento, dor aguda, agitação, bradicardia e taquicardia. Conclusão: a enfermagem perioperatória deve manter-se atualizada e ter domínio dos melhores cuidados ofertados ao cliente, a fim de evitar riscos e tratar complicações que podem vir a acontecer.

Objective: to identify in the literature the most recurrent post anesthetic discomforts/complications and nursing interventions. Methodology: this is an integrative review. The criteria used were: articles published in scientific literature, national and international, available in full, languages: Portuguese, English or Spanish, free access to databases of selected data, with no year limit, that answered the guiding question: "What are the nursing interventions in relation to the complications/discomforts in adults in the Post-anesthetic Recovery Room?" Results: 1261 were found, after inclusion criteria were performed with 9 studies. Hypothermia and hyperthermia, hypoxemia, hypertension and hypotension, nausea and vomiting, urinary retention, bleeding, acute pain, agitation, bradycardia and tachycardia were identified and classified as categorical. Conclusion: perioperative nursing must be kept up to date and master the best care offered to the client in order to avoid risks and treat complications that may occur.

A new species of Hypopygus Hoedeman (Gymnotiformes: Rhamphichthyidae) from the rio Trombetas system, Amazon basin, Brazil.

A new Hypopygus species is described from the igarapé Saracá, a stream in the lower rio Trombetas system, Pará State, Brazil. It differs from congeners by a unique combination of characters (either primitive or of uncertain polarity) which includes mouth position, interocular width, snout length, postorbital length, pectoral-fin length, snout-to-occiput length, caudal-filament length, counts of pectoral-fin rays and anal-fin rays, distribution of anal-fin chomatophores, as well as a set of osteological features. A phylogenetic analysis indicates that the new species, belongs to a monophyletic subgroup in Hypopygus that includes all congeners, except H. neblinae; its relationships within that clade, however, are currently uncertain, and a brief discussion is provided. Corrections are made concerning some morphometric and meristic information furnished in recent contributions regarding Hypopygus species.

A new species of Eigenmannia Jordan and Evermann (Gymnotiformes: Sternopygidae) from the upper rio Paraguai basin.

Eigenmannia correntes, a new species belonging to the Eigenmannia trilineata species-group, is described from tributaries of rio Correntes, a major affluent of the rio Piquiri system, upper rio Paraguai basin (Mato Grosso and Mato Grosso do Sul states, Brazil). Eigenmannia correntes is included in the currently poorly defined sternopygid genus Eigenmannia (Ostariophysi: Gymnotiformes) by presenting characters that are either primitive or of uncertain polarity, such as eyes covered by skin, scales present over entire postcranial portion of body, teeth absent from oral valve, infraorbital bones 1+2 with enlarged posterodorsal expansion, and gill rakers short and unossified. The new species is distinguished from all congeners, except those species included in the Eigenmannia trilineata species-group, by the presence of a conspicuous superior midlateral stripe (synapomorphy of this clade). Eigenmannia correntes can be differentiated from all members of the Eigenmannia trilineata species-group, except E. vicentespelaea, E. waiwai and E. besouro, by its subterminal mouth (vs. terminal in remaining species of that group). Further, it differs from these aforementioned species by a number of meristic and morphometric characters, including number of premaxillary and dentary teeth, number of longitudinal series of scales above lateral line, number of pectoral-fin and anal-fin rays, eye diameter, postorbital distance, and snout length. Finally, notes on reproduction and parasitism for E. correntes are presented.

Adjacent-level degeneration after cervical disc arthroplasty versus fusion.

INTRODUCTION: The principal objective of this study was to evaluate the incidence of adjacent-segment degeneration (ASD) in patients who underwent cervical disc arthroplasty (CDA) as compared with anterior cervical discectomy and fusion (ACDF). METHODS: It is a prospective cohort study of patients with a single-level cervical degenerative disc disease from C3 to C7 who underwent CDA or ACDF between January 2004 and December 2006, with a minimum follow-up of 3 years. The patients were evaluated pre- and postoperatively with the visual analog scale (VAS), the neck disability index (NDI), and a complete neurological examination. Plain radiographic assessments included sagittal-plane angulation, range of motion (ROM), and radiological signs of ASD. RESULTS: One hundred and five patients underwent ACDF and 85 were treated with CDA. The postoperative VAS and NDI were equivalent in both groups. The ROM was preserved in the CDA group but with a small decreased tendency within the time. Radiographic evidence of ASD was found in 11 (10.5%) patients in the ACDF group and in 7 (8.8%) subjects in the CDA group. The Kaplan-Meier survival analysis for the ASD occurrence did not reach statistically significant differences (log rank, P = 0.72). CONCLUSIONS: Preservation of motion in the CDA patients was not associated with a reduction of the incidence of symptomatic adjacent-segment disease and there may be other factors that influence ASD.

Earliest evidence of mammalian social behaviour in the basal Tertiary of Bolivia.

The vast majority of Mesozoic and early Cenozoic metatherian mammals (extinct relatives of modern marsupials) are known only from partial jaws or isolated teeth, which give insight into their probable diets and phylogenetic relationships but little else. The few skulls known are generally crushed, incomplete or both, and associated postcranial material is extremely rare. Here we report the discovery of an exceptionally large number of almost undistorted, nearly complete skulls and skeletons of a stem-metatherian, Pucadelphys andinus, in the early Palaeocene epoch of Tiupampa in Bolivia. These give an unprecedented glimpse into early metatherian morphology, evolutionary relationships and, especially, ecology. The remains of 35 individuals have been collected, with 22 of these represented by nearly complete skulls and associated postcrania. These individuals were probably buried in a single catastrophic event, and so almost certainly belong to the same population. The preservation of multiple adult, sub-adult and juvenile individuals in close proximity (<1 m(2)) is indicative of gregarious social behaviour or at least a high degree of social tolerance and frequent interaction. Such behaviour is unknown in living didelphids, which are highly solitary and have been regarded, perhaps wrongly, as the most generalized living marsupials. The Tiupampan P. andinus population also exhibits strong sexual dimorphism, which, in combination with gregariousness, suggests strong male-male competition and polygyny. Our study shows that social interactions occurred in metatherians as early as the basal Palaeocene and that solitary behaviour may not be plesiomorphic for Metatheria as a whole.

[Cerebellopontine angle epidermoid cysts. Experience of 43 cases with long-term follow-up].

BACKGROUND: Epidermoid tumors represent the third most common lesion of the cerebellopontine angle (CPA). Their evolution and clinical features are distinctively characteristic. We present a comprehensive review of the clinical, imaging and surgical aspects of epidermoid cysts of the CPA. METHODS: We conducted a case series of patients diagnosed with epidermoid cyst of the CPA who were operated on between 1998 and 2005. Lesions were classified according to their anatomic extent: grade I(-) within the boundaries of the CPA, grade II(-) extension to the suprasellar and perimesencephalic cisterns, and grade III(-) parasellar and temporomesial region involvement. RESULTS: This study was comprised of 43 patients with a mean follow-up of 85 months. Mean age was 34 years, and 67% of the patients were female. The initial symptom was headache in 58.1% of the cases and trigeminal neuralgia in 41.8%. According to our classification, temporomesial involvement (25.6%) was significantly (p = 0.001) associated with a higher incidence of seizures, and trigeminal neuralgia was present in patients with lesions limited to the CPA (p = 0.006). The lesions were reached essentially through a retrosigmoidal approach (39.5%) and surgical excision was deemed to be complete in 65% of the cases. CONCLUSIONS: Our grading classification according to the anatomic extension correlates well with clinical presentation, type of surgical approach and extent of surgical removal. It is desirable to reach a consensus on the classification of tumor extension.

Quistes epidermoides del ángulo pontocerebeloso: experiencia en 43 casos con seguimiento a largo plazo / Cerebellopontine angle epidermoid cysts: experience of 43 cases with long-term follow-up

Introducción: El quiste epidermoide ocupa el tercer lugar de los tumores en la región del ángulo pontocerebeloso. El presente informe describe los principales aspectos clínicos, radiológicos y el manejo quirúrgico de este tipo de quistes en esa ubicación. Material y métodos: Serie de pacientes operados de quiste epidermoide del ángulo pontocerebeloso entre 1998 y 2005. Se clasificó la extensión de la lesión según las cisternas involucradas: extensión I, limitada al ángulo pontocerebeloso; extensión II, cisternas ángulo pontocerebeloso + supraselar + perimesencefálicas; extensión III, ángulo pontocerebeloso con extensión paraselar y temporomesial. Resultados: 43 pacientes con seguimiento promedio de 85 meses, la edad media fue de 34 años; 67 % fue del sexo femenino. Los principales síntomas fueron cefalea (58.1 %) y afección trigeminal (41.8 %). De acuerdo con nuestra clasificación, los pacientes con extensión temporomesial (25.6 %) presentaron mayor incidencia de epilepsia secundaria (p = 0.001), y aquellos con neuralgia del trigémino tuvieron lesiones más limitadas al ángulo pontocerebeloso (p = 0.006). El abordaje más empleado fue el retrosigmoideo (39.5 %); la resección tumoral fue completa en 65 % de los pacientes. Conclusiones: Existen diferencias en la presentación clínica, grado de resección quirúrgica y recurrencia tumoral entre las diferentes extensiones del quiste epidermoide del ángulo pontocerebeloso, por lo que se requiere abordaje terapéutico específico. Para que las comparaciones entre series sea válida, es deseable el consenso y la elaboración de una clasificación consensuada acerca las extensiones del quiste epidermoide en esa ubicación.

BACKGROUND: Epidermoid tumors represent the third most common lesion of the cerebellopontine angle (CPA). Their evolution and clinical features are distinctively characteristic. We present a comprehensive review of the clinical, imaging and surgical aspects of epidermoid cysts of the CPA. METHODS: We conducted a case series of patients diagnosed with epidermoid cyst of the CPA who were operated on between 1998 and 2005. Lesions were classified according to their anatomic extent: grade I(-) within the boundaries of the CPA, grade II(-) extension to the suprasellar and perimesencephalic cisterns, and grade III(-) parasellar and temporomesial region involvement. RESULTS: This study was comprised of 43 patients with a mean follow-up of 85 months. Mean age was 34 years, and 67% of the patients were female. The initial symptom was headache in 58.1% of the cases and trigeminal neuralgia in 41.8%. According to our classification, temporomesial involvement (25.6%) was significantly (p = 0.001) associated with a higher incidence of seizures, and trigeminal neuralgia was present in patients with lesions limited to the CPA (p = 0.006). The lesions were reached essentially through a retrosigmoidal approach (39.5%) and surgical excision was deemed to be complete in 65% of the cases. CONCLUSIONS: Our grading classification according to the anatomic extension correlates well with clinical presentation, type of surgical approach and extent of surgical removal. It is desirable to reach a consensus on the classification of tumor extension.

A role for chlorophyllide a oxygenase in the regulated import and stabilization of light-harvesting chlorophyll a/b proteins.

The Arabidopsis CAO gene encodes a 52-kDa protein with predicted localization in the plastid compartment. Here, we report that CAO is an intrinsic Rieske iron-sulfur protein of the plastid-envelope inner and thylakoid membranes. Activity measurements revealed that CAO catalyzes chlorophyllide a to chlorophyllide b conversion in vitro and that the enzyme was only slightly active with protochlorophyllide a, the nonreduced precursor of chlorophyllide a. Protein import and organelle fractionation studies identified CAO to be distinct from Ptc52 in the substrate-dependent transport pathway of NADPH:protochlorophyllide oxidoreductase A but instead to be part of a separate translocon complex. This complex was involved in the regulated import and stabilization of the chlorophyllide b-binding light-harvesting proteins Lhcb1 (LHCII) and Lhcb4 (CP29) in chloroplasts. Together, our results provide insights into the plastid subcompartmentalization and evolution of chlorophyll precursor biosynthesis in relation to protein import in higher plants.

Miocardiopatía periparto: patología infrecuente de difícil diagnóstico / Peripartum cardiomyopathy: infrequent pathology of difficult diagnosis

Se presenta un caso de miocardiopatía periparto en paciente de 17 años de edad que evoluciona con un embarazode curso fisiológicoy que consulta al Servicio de Obstetricia con trabajo de parto prematuro y rotura espontánea de membranas (REM) de 8 horas de evolución. En el puerperio inmediato, luego de un parto vaginal con un sagarmiento excesivo, presenta elementos de hipotensión y taquicardía a los que rápidamente se agregan taquiarritmias supraventriculares y fenómenos de congestión pulmonar que no revierten a pesar del manejo antiarrítmico, la restitución de fluidos y las transfuciones de glóbulos rojos. Es trasladadaa la unidad de atenció intermedia en donde la ecografía revela elementos que permiten plantear el diagnóstico definitivo e instaurar el tratamiento adecuado. Se revisa el tema y dada su baja frecuencia y su propósito ominoso se presenta el caso clínico y su resolución