Neumoencéfalo, una revisión de literatura

El neumoencéfalo corresponde a la presencia de aire intracraneal y, en general, es asintomático y autolimitado. Puede ocurrir posterior a trauma, cirugía craneofacial, defectos congénitos, infección, neoplasia o de forma espontánea. El neumoencéfalo a tensión es una emergencia neuroquirúrgica, en la que se acumula aire intracraneal de forma continua que genera un efecto de masa. Clínicamente, se caracteriza por cefalea y un deterioro neurológico marcado. A pesar de ser poco frecuente, es relevante considerar el neumoencéfalo a tensión como una posible complicación en pacientes con antecedente de neurocirugía y/o cirugía otorrinolaringológica, debido a que es una patología potencialmente grave. El diagnóstico es clínico e imagenológico, y requiere de un alto índice de sospecha. Un manejo oportuno es relevante para prevenir la herniación y la muerte.

Pneumocephalus refers to the presence of air in the cranial cavity, and in general, is self-limited and asymptomatic. It can occur after trauma, craniofacial surgery, due to congenital defects, infection, neoplasia or spontaneously. Tension pneumocephalus is a neurosurgical emergency in which intracranial air accumulates continuously, causing a mass effect. It presents with headache and marked neurological deterioration. Despite being rare, it is relevant to consider tension pneumocephalus as a possible complication in patients with a history of neurosurgery and/or otolaryngology surgery, as it can be life-threatening. Diagnosis requires a high index of suspicion and imagenologic confirmation. Timely management is relevant to prevent herniation and death.

Application of Raman spectroscopy for the determination of proteins denaturation and amino acids decomposition temperature.

Raman spectroscopy was employed to study the thermal denaturation of three different proteins, bovine serum albumin (BSA), lysozyme, ovalbumin; and the decomposition temperature of three amino acids, l-glutamine, l-cysteine, and l-alanine, all of them as lyophilized powders. All the Raman bands observed in the spectra obtained were recorded and analyzed at preset heating temperatures. The results obtained for either protein denaturation temperature TD and amino acid decomposition temperatures TM-dc, were compared with those measured by differential scanning calorimetry (DSC). The DSC and Raman results were additionally corroborated with a thermogravimetric analysis (TGA) for the case of proteins. This exercise indicated almost complete coincidence in the determination of these transition temperatures between the three techniques, evidencing the applicability of Raman spectroscopy in the study of denaturation and decomposition temperatures of proteins and amino acids.

Neumoencéfalo recurrente post quirúrgico, a raíz de dos casos / Post-surgical late pneumoencephalus, based on two cases

El neumoencéfalo es una patología que comúnmente se presenta después de cirugía neuroquirúrgica y ocasionalmente endonasal. Estos se suelen manejar de manera conservadora, sin embargo, se pueden asociar a distintas etiologías las cuales los hacen recurrir. En este reporte presentamos dos casos de neumoencéfalo tardío post quirúrgico asociado a fístulas de LCR de bajo flujo, donde se discute su clínica, etiología y manejo posterior.

Pneumocephalus is a pathology that commonly occurs after endonasal surgery, these are usually managed conservatively, however they can be associated with different etiologies which make them recur. In this report we present two cases of post-surgical late pneumocephalus associated with low-flow CSF fistulae, where its symptoms, etiology, and subsequent management are discussed.

Neuralgia del nervio glosofaríngeo posamigdalectomía: reporte de dos casos / Post-tonsillectomy glossopharyngeal nerve neuralgia: report of two cases

Resumen La amigdalectomía es uno de los procedimientos quirúrgicos más frecuentes que realiza el otorrinolaringólogo. Dentro de las complicaciones posoperatorias, la neuralgia del nervio glosofaríngeo es extremadamente poco frecuente. En este artículo se presentan dos casos clínicos pediátricos con neuralgia del glosofaríngeo posamigdalectomía que fueron resueltos con tratamiento médico.

Abstract Tonsillectomy is one of the most common procedures done by the otolaryngologist. Among post-operative complications, the glossopharyngeal neuralgia is extremely uncommon. This article presents two pediatric clinical cases with post-tonsillectomy glossopharyngeal neuralgia that were resolved with medical treatment.

Determination of the denaturation temperature of the Spike protein S1 of SARS-CoV-2 (2019 nCoV) by Raman spectroscopy.

In the present work the temperature response of the constitutive S1 segment of the SARS-CoV-2 Spike Glycoprotein (GPS) has been studied. The intensity of the Raman bands remained almost constant before reaching a temperature of 133 °C. At this temperature a significant reduction of peak intensities was observed. Above 144 °C the spectra ceased to show any recognizable feature as that of the GPS S1, indicating that it had transformed after the denaturation process that it was subjected. The GPS S1 change is irreversible. Hence, Raman Spectroscopy (RS) provides a precision method to determine the denaturation temperature (TD) of dry powder GPS S1. The ability of RS was calibrated through the reproduction of TD of other well studied proteins as well as those of the decomposition temperature of some amino acids (AA). Through this study we established a TD of 139 ± 3 °C for powder GPS S1 of SARS-CoV-2.

Epidemiología del síndrome coronario agudo / Epidemiology of the acute coronary syndrome / Epidemiologia da síndrome coronária aguda

Las enfermedades cardiovasculares son la principal causa de muerte en el mundo. Su incidencia y prevalencia aumentan con la edad y con los diferentes factores de riesgo. La mayoría de estos factores tienen una relación estrecha con el estilo de vida; factores como la dislipidemia, el tabaquismo, la hipertensión, la diabetes mellitus, la obesidad y el estrés son cada vez más prevalentes y varían según la población y localización geográfica. Por eso se realiza una revisión de la epidemiología mundial y nacional del síndrome coronario agudo, y de cómo este ha variado a través de los años. Se buscó literatura en inglés y español en diferentes bases de datos, fueron seleccionados 50 artículos que se presentan haciendo énfasis en el impacto epidemiológico del síndrome coronario agudo. Luego de realizar la revisión detallada se concluye que la enfermedad cardiovascular persiste como primera causa mundial de morbimortalidad, con aumento en su frecuencia durante los últimos años. El síndrome coronario agudo es la afección que provoca más muertes entre todos los eventos, con incidencia, edad de presentación, impacto económico y factores de riesgo diferentes de acuerdo con cada región. Los factores de riesgo modificables siguen siendo muy importantes en el desarrollo de enfermedades cardiovasculares.

Cardiovascular diseases are the main cause of mortality all over the world. Their incidence and prevalence increase with age and different risk factors. The majority of factors are closely related to the lifestyle; aspects such as hypertension, diabetes mellitus, obesity, and stress are more prevalent day by day and vary according to the population and its geographical location. The researchers made a revision on international and national epidemiology of the acute coronary syndrome and it has changed over the years. The study included literature published in both English and Spanish retrieved from different databases. For this particular case, 50 articles focused on the epidemiologic impact of the acute coronary syndrome were reviewed. After a detailed revision, it can be said that the cardiovascular disease, which has been increasing during the past years, remains as the first cause of morbidity and mortality at the worldwide level. This syndrome causes more deaths in all events, with different incidence, age in which it takes place, economic impact and risk factors, depending on each region. The modifiable risk factors are still very important in the development of cardiovascular diseases.

As doenças cardiovasculares são as principais causas de morte no mundo. Sua incidência e prevalência aumentam com a idade e com os diferentes fatores de risco. A maioria destes fatores têm uma relação estreita com o estilo de vida; fatores como a dislipidemia, o tabaquismo, a hipertensão, a diabetes mellitus, a obesidade e o estresse são cada vez mais prevalentes e variam segundo a população e localização geográfica. Por isso se realiza uma revisão da epidemiologia mundial e nacional da síndrome coronária aguda, e de como este há variado através dos anos. Se buscou literatura em inglês e espanhol em diferentes bases de dados, foram selecionados 50 artigos que se apresentam fazendo ênfase no impacto epidemiológico da síndrome coronária aguda. Logo de realizar a revisão detalhada se conclui que a doença cardiovascular persiste como primeira causa mundial de morbimortalidade, com aumento na sua frequência durante os últimos anos. A síndrome coronária aguda é a afecção que provoca mais mortes entre todos os eventos, com incidência, idade de apresentação, impacto econômico e fatores de risco diferentes de acordo com cada região. Os fatores de risco modificáveis seguem sendo muito importantes no desenvolvimento de doenças cardiovasculares.

Silencing of the transcriptional factor ZEB1 alters the steroidogenic pathway, and increases the concentration of testosterone and DHT in DU145 cells.

Prostate cancer (PCa) is the second most common type of male malignancy worldwide. The transcription factor zinc finger E­box binding homeobox 1 (ZEB1) is associated with epithelial­mesenchymal transition and is also involved in regulation of androgen receptor (AR) expression, the main ligands of which are testosterone and dihydrotestosterone (DHT). These androgens are synthesized through the steroidogenic pathway within the prostate, and their synthesis is altered in PCa. The present study aimed to determine the ZEB1­induced alterations in androgen synthesis and AR expression in the DU145 PCa cell line. Reverse transcription­quantitative polymerase chain reaction, western blotting and immunocytochemistry were used to determine the mRNA and protein expression levels, and cellular localization of steroidogenic pathway enzymes in the DU145 cell line in response to ZEB1 silencing. Furthermore, the concentrations of testosterone and DHT were detected in cell culture medium using ELISA. ZEB1­silenced cells exhibited an increase in testosterone and DHT production, an increase in AR expression and an alteration in the steroidogenic pathway. In particular, steroidogenic acute regulatory protein and 5α­reductase 2 expression levels were decreased, whereas cytochrome P450 family 17 subfamily A member 1, 5α­reductase 1, aldo­keto reductase family 1 member D1 and aldo­keto reductase family 1 member C2 expression levels were increased. In conclusion, the present study provided novel information regarding the regulation of intratumoral androgen production in PCa, which is relevant for the progression of the disease to a castration­resistant form.

Tratamiento de pseudoaneurisma iatrogénico con compresión ecoguiada / Treatment of iatrogenic pseudoaneurysm with echo-guided compression

Resumen Objetivo: Evaluar la efectividad obtenida con la compresión ecoguiada como primera elección para lograr la trombosis del pseudoaneurisma iatrogénico post estudio o intervencionismo. Material y Método: Estudio retrospectivo observacional de 9 pacientes en quienes se realizó la compresión ecoguiada como primera alternativa de manejo frente a pseudoaneurismas iatrogénicos secundarios a procedimientos diagnósticos o terapéuticos ocurridos entre agosto de 2012 y diciembre de 2015 en el Hospital Regional de Talca. Resultados: De 4.070 procedimientos se presentó la complicación en 9 pacientes, un 0,22%; 7 posterior a procedimientos terapéuticos (0,4%), y 2 en el grupo de diagnósticos (0,08%). La muestra se compone por 6 hombres y 3 mujeres de edad promedio 70 años. El vaso comprometido fue principalmente la arteria femoral con un 77%. Los pseudoaneurismas ocurrieron mayoritariamente posteriores a procedimientos terapéuticos (77%); y el éxito de la compresión ecoguiada se obtuvo en el 67%. No hubo complicaciones asociadas al tratamiento. Conclusiones: La compresión ecoguiada tiene un porcentaje de éxito menor en esta pequeña serie que los obtenidos por otros autores, pero al no presentar complicaciones y por su bajo costo creemos debe mantenerse como primera alternativa.

Objective: To evaluate the effectiveness obtained with echo guided compression as the first choice to achieve thrombosis of iatrogenic pseudoaneurysm after study or interventionism. Material and Method: Retrospective observational study of 9 patients who underwent echo-guided compression as the first management alternative to iatrogenic pseudoaneurysms following diagnostic or therapeutic procedures that occurred between August 2012 and December 2015 at the Regional Hospital of Talca. Results: Of 4,070 procedures the complication was presented in 9 patients, 0.22%; 7 after therapeutic procedures (0.4%), and 2 in the diagnostic group (0.08%). The sample consists of 6 men and 3 women of average age 70 years. The involved vessel was mainly the femoral artery with 77%. Pseudoaneurysms occurred mostly after therapeutic procedures (77%); and the success of the echogenic compression was obtained in 67%. There were no complications associated with treatment. Conclusions : Image guided compression has a lower success rate in this small series than those obtained by other authors, but since there are no complications and because of its low cost, we believe that it should be kept as the first alternative.

Search for Event Rate Modulation in XENON100 Electronic Recoil Data.

We have searched for periodic variations of the electronic recoil event rate in the (2-6) keV energy range recorded between February 2011 and March 2012 with the XENON100 detector, adding up to 224.6 live days in total. Following a detailed study to establish the stability of the detector and its background contributions during this run, we performed an unbinned profile likelihood analysis to identify any periodicity up to 500 days. We find a global significance of less than 1σ for all periods, suggesting no statistically significant modulation in the data. While the local significance for an annual modulation is 2.8σ, the analysis of a multiple-scatter control sample and the phase of the modulation disfavor a dark matter interpretation. The DAMA/LIBRA annual modulation interpreted as a dark matter signature with axial-vector coupling of weakly interacting massive particles to electrons is excluded at 4.8σ.

Papanicolaou y citología líquida en diagnóstico de cáncer de cérvix: Hospital Civil de Maracay. 2012 / Papanicolaou and liquid in cytology cervical cancer diagnosis of Civil Hospital Maracay. 2012.

Con el objetivo de comparar la citología ginecológica de Base Líquida, con la citología convencional de Papanicolaou, en la detección de lesiones precancerosas y cancerosas de cuello uterino, se realizó un estudio de Tamizaje, en 144 pacientes aparentemente sanas que se presentaron a las consultas de ITS e Higiene del Adulto del Ambulatorio Efraín Abad, Maracay, durante el primer semestre de 2012, practicándoseles una encuesta y una muestra vaginal para cada prueba. Por Papanicolaou resultaron negativas 111 muestras y 33 insatisfactorias. De la citología líquida, 135 fueron negativas y detectados 9 casos (6,25%), de lesiones Intraepiteliales de Bajo Grado, cinco de ellas negativas con Papanicolaou y cuatro insatisfactorias. Los resultados refieren, la asociación de la promiscuidad sexual de la paciente y/o su pareja, sin protección como principal causa de cáncer de cérvix. El empleo de esta nueva técnica citológica, es un avance científico, que permitirá detectar todos los casos existentes, por su alta sensibilidad y especificidad en comparación con la de Papanicolaou, por lo tanto implementarla será una estrategia de promoción, prevención y atención en el programa nacional de cáncer de cuello uterino.

In order to compare the liquid-based gynecologic cytology with conventional cytology Pap in detecting precancerous lesions and cervical cancer, a study of screening in 144 apparently healthy patients who presented to queries STIs and Health outpatient adult Ephraim Abbot, Leeds, during the first half of 2012, a survey and practiced vaginal sample for each test. For Pap 111 samples were negative and 33 unsatisfactory. Of liquid-based cytology, 135 were negative and detected 9 cases (6.25%) of lowgrade intraepithelial lesions, including five negative and four unsatisfactory Pap. The results relate the association of sexual promiscuity of the patient and / or their partners, unprotected as the main cause of cervical cancer. Using this new technique cytological, is a scientific breakthrough that will identify all existing cases, by its high sensitivity and specificity compared with Pap therefore will implement a strategy of promotion, prevention and care program national cervical Cancer.

Proapoptotic effect of endocannabinoids in prostate cancer cells.

In the early stages, prostate cancer is androgen­ dependent; therefore, medical castration has shown significant results during the initial stages of this pathology. Despite this early effect, advanced prostate cancer is resilient to such treatment. Recent evidence shows that derivatives of Cannabis sativa and its analogs may exert a protective effect against different types of oncologic pathologies. The purpose of the present study was to detect the presence of cannabinoid receptors (CB1 and CB2) on cancer cells with a prostatic origin and to evaluate the effect of the in vitro use of synthetic analogs. In order to do this, we used a commercial cell line and primary cultures derived from prostate cancer and benign prostatic hyperplasia. The presence of the CB1 and CB2 receptors was determined by immunohistochemistry where we showed a higher expression of these receptors in later stages of the disease (samples with a high Gleason score). Later, treatments were conducted using anandamide, 2-arachidonoyl glycerol and a synthetic analog of anandamide, methanandamide. Using the MTT assay, we proved that the treatments produced a cell growth inhibitory effect on all the different prostate cancer cultures. This effect was demonstrated to be dose-dependent. The use of a specific CB1 receptor blocker (SR141716) confirmed that this effect was produced primarily from the activation of the CB1 receptor. In order to understand the MTT assay results, we determined cell cycle distribution by flow cytometry, which showed no variation at the different cell cycle stages in all the cultures after treatment. Treatment with endocannabinoids resulted in an increase in the percentage of apoptotic cells as determined by Annexin V assays and caused an increase in the levels of activated caspase-3 and a reduction in the levels of Bcl-2 confirming that the reduction in cell viability noted in the MTT assay was caused by the activation of the apoptotic pathway. Finally, we observed that endocannabinoid treatment activated the Erk pathway and at the same time, produced a decrease in the activation levels of the Akt pathway. Based on these results, we suggest that endocannabinoids may be a beneficial option for the treatment of prostate cancer that has become nonresponsive to common therapies.

Regulation of protein translation and c-Jun expression by prostate tumor overexpressed 1.

Prostate tumor overexpressed-1 (PTOV1), a modulator of the Mediator transcriptional regulatory complex, is expressed at high levels in prostate cancer and other neoplasias in association with a more aggressive disease. Here we show that PTOV1 interacts directly with receptor of activated protein C kinase 1 (RACK1), a regulator of protein kinase C and Jun signaling and also a component of the 40S ribosome. Consistent with this interaction, PTOV1 was associated with ribosomes and its overexpression promoted global protein synthesis in prostate cancer cells and COS-7 fibroblasts in a mTORC1-dependent manner. Transfection of ectopic PTOV1 enhanced the expression of c-Jun protein without affecting the levels of c-Jun or RACK1 mRNA. Conversely, knockdown of PTOV1 caused significant declines in global protein synthesis and c-Jun protein levels. High levels of PTOV1 stimulated the motility and invasiveness of prostate cancer cells, which required c-Jun, whereas knockdown of PTOV1 strongly inhibited the tumorigenic and metastatic potentials of PC-3 prostate cancer cells. In human prostate cancer samples, the expression of high levels of PTOV1 in primary and metastatic tumors was significantly associated with increased nuclear localization of active c-Jun. These results unveil new functions of PTOV1 in the regulation of protein translation and in the progression of prostate cancer to an invasive and metastatic disease.

Modulación del metabolismo de esfingolípidos en cáncer de vejiga como una potencial estrategia para optimizar resultados de terapias intravesicales para tumores de vejiga no musculoinvasores / Modulation of sphingolipid metabolism in bladder cancer as a potential strategy to optimize outcomes of intravesical therapies for non-muscle invasive bladder cancers

El cáncer de vejiga representa un problema de salud pública importante a nivel mundial. En Chile su relevancia es aún mayor en la región de Antofagasta. Este cáncer se caracteriza por una alta tasa de recurrencia, por lo que los pacientes requieren un seguimiento estricto que afecta su calidad de vida e implica elevados costos para los sistemas de salud. Esto explica la necesidad de optimizar los tratamientos actuales (quimioterapia e inmunoterapia con BCG intravesical) para reducir las tasas de recurrencia y progresión. Los esfingolípidos son lípidos bioactivos que a nivel celular cumplen funciones relacionadas con la regulación del crecimiento, proliferación, migración, invasión, resistencia a drogas y apoptosis. La evidencia disponible a la fecha sobre el rol de los esfingolípidos en cáncer de vejiga es escasa, pero sugiere que en este cáncer existe un metabolismo esfingolipídico desplazado hacia la reducción de los niveles intracelulares de ceramida y esfingosina (esfingolípidos pro-apoptóticos) y aumento de esfingosina 1-fosfato (esfingolípido anti-apoptótico). La manipulación del metabolismo esfingolipídico para invertir esta relación se propone en esta revisión como una estrategia que podría ayudar a optimizar el efecto de las terapias disponibles actualmente para reducir las recurrencias y progresiones de los tumores de vejiga no músculo-invasores...

Bladder cancer is an important health problem worldwide. In Chile it has particular relevance in the region of Antofagasta. This cancer is characterized by a high recurrence rate, for which patients need a strict follow up that impairs their quality of life and determines increased costs for health care systems. These facts explain the necessity of optimizing the actual treatments (chemotherapy and BCG immunotherapy) for reducing the rates of recurrence and progression. Sphingolipids are bioactive lipids that at a cellular level have roles related to the regulation of growth, proliferation, migration, invasiveness, drug resistance and apoptosis. To date, the available evidence about the role of sphingolipids in bladder cancer is scarce, but suggests that in this cancer there is a sphingolipid metabolism shifted towards a reduction of the intracellular levels of ceramide and sphingosine (pro-apoptotic sphingolipids) and an increase of sphingosine 1-phosphate (anti-apoptotic sphingolipid). In this review we propose that the manipulation of the sphingolipid metabolism to invert this balance can contribute to optimize the effect of the actual therapies to reduce the rates of recurrence and progression of non-muscle invasive bladder cancers...

Esfingosina-1-fosfato y cánceres urológicos: identificando potenciales blancos terapéuticos en su etabolismo y señalización / Sphingosine-1-phosphate and urological cancers: identifying potential therapeutic targets in its metabolism and signalling

Los lípidos no sólo son moléculas estructurales de las membranas. Hay numerosos ejemplos de lípidos que median acciones fisiológicas dentro de las células. Específicamente, esfingolípidos como ceramida, esfingosina y esfingosina-1-fosfato (S1P) han sido involucrados en el control del crecimiento celular, la proliferación y la migración, todo lo cual se ha relacionado con el cáncer.Los efectos pro-apoptóticos de la ceramida y la esfingosina son revertidos por S1P. Por lo tanto, el destino de la célula puede ser modulada mediante el cambio de la proporción de estos esfingolípidos (el modelo reóstato). S1P promueve la proliferación celular, el crecimiento, la supervivencia, la migración, invasión y resistencia fármacos y radiación, en parte a través de receptores de membrana (S1PR1-5). La sobreexpresión de enzimas productoras de S1P y el aumento de los niveles de S1P se ha descrito en muchos tipos de cáncer, incluyendo cánceres urológicos. Por lo tanto, se pueden identificar posibles objetivos terapéuticos en el metabolismo y las vías de señalización de los esfingolípidos, cuya relevancia clínica debe ser determinada en futuros estudios.

Lipids are not only structural molecules of the membranes. There are numerous examples of lipids mediating physiologic actions within the cells. Specifically, sphingolipids like ceramide, sphingosine and sphingosine-1-phosphate (S1P) have been described to be involved in the control of cell growth, proliferation and migration, all of which has been linked to cancer. The pro-apoptotic effects of ceramide and sphingosine are opposed by S1P. Therefore, the fate of the cell can be modulated by changing the ratio of these sphingolipids (the rheostat model). S1P promotes cell proliferation, growth, survival, migration, invasion and resistance to drugs and radiation, in part mediated by S1P membrane receptors (S1PR1-5). Overexpression of S1P producing enzymes and increased S1P levels has been described in many cancers, including urological cancers. Therefore, potential therapeutic targets can be recognized in the metabolism and signaling pathways of sphingolipids and their clinical relevance have to be determined in future studies.

Limits on spin-dependent WIMP-nucleon cross sections from 225 live days of XENON100 data.

We present new experimental constraints on the elastic, spin-dependent WIMP-nucleon cross section using recent data from the XENON100 experiment, operated in the Laboratori Nazionali del Gran Sasso in Italy. An analysis of 224.6 live days×34 kg of exposure acquired during 2011 and 2012 revealed no excess signal due to axial-vector WIMP interactions with 129Xe and 131Xe nuclei. This leads to the most stringent upper limits on WIMP-neutron cross sections for WIMP masses above 6 GeV/c², with a minimum cross section of 3.5×10(-40) cm² at a WIMP mass of 45 GeV/c², at 90% confidence level.

Dark matter results from 225 live days of XENON100 data.

We report on a search for particle dark matter with the XENON100 experiment, operated at the Laboratori Nazionali del Gran Sasso for 13 months during 2011 and 2012. XENON100 features an ultralow electromagnetic background of (5.3 ± 0.6) × 10(-3) events/(keV(ee) × kg × day) in the energy region of interest. A blind analysis of 224.6 live days × 34 kg exposure has yielded no evidence for dark matter interactions. The two candidate events observed in the predefined nuclear recoil energy range of 6.6-30.5 keV(nr) are consistent with the background expectation of (1.0 ± 0.2) events. A profile likelihood analysis using a 6.6-43.3 keV(nr) energy range sets the most stringent limit on the spin-independent elastic weakly interacting massive particle-nucleon scattering cross section for weakly interacting massive particle masses above 8 GeV/c(2), with a minimum of 2 × 10(-45) cm(2) at 55 GeV/c(2) and 90% confidence level.

Effects of diet and water supply on energy intake and water loss in a mygalomorph spider in a fluctuating environment of the central Andes.

The metabolic and water evaporation strategies in spiders may be part of a set of physiological adaptations to tolerate low or unpredictable food availability, buffering spiders against environmental fluctuations such as those of the high mountains of the central Andes. The aim of this study is to analyze experimentally the variations in metabolic rate and the rate of evaporative water with food and/or water restriction in a high mountain mygalomorph spider population (Paraphysa sp.). We found that the low metabolism of this spider was not affected by water restriction, but its metabolism was depressed after 3 weeks of food deprivation. The spider did not show seasonal metabolic changes but it presented seasonal changes in the rate of evaporative water loss at high temperatures. Females with egg sacs reduced their metabolic rate and evaporative water at high temperatures. These findings constitute a set of possible adaptations to a highly fluctuating Mediterranean environment, which is completely covered with snow for many months and then progresses rapidly to a very dry climate with high temperatures.

[Perineal endometriosis with anal external sphincter involvement: a case-report]. / Endometrioma perianal involucrando esfínter anal externo: reporte de un caso.

The presence of perianal endometriosis involving the anal sphincter is a rare presentation of this disease, most cases are diagnosed late and few are reported in the literature despite the number of episiotomies performed today. We present a case in a female with perianal symptoms after an episiotomy 15 years ago and visualized by endoanal ultrasound. We also review the literature of this condition. The treatment of choice is wide excision of the lesion involving the anal sphincter so the sphincter defect should be repaired by sphincteroplasty. According to the literature, early diagnosis by clinical suspicion and confirmation by endoanal ultrasound, with wide excision of endometrioma gives satisfactory results regarding anal continence.

Participation of book lungs in evaporative water loss in Paraphysa parvula, a migalomorph spider from Chilean Andes.

Small animals need efficient water conservation mechanisms for survival and reproduction, which is relevant for the spiders that have large book lungs with large respiratory surface. If lung evaporation is relevant to limit water loss, adjustments of the spiracle opening to metabolic demands should be expected. In this study, we measured the metabolic rate and total evaporative water loss mediated by the opening of the spiracles in the migalomorph spider Paraphysa parvula, a resident of fluctuating Mediterranean environments of the mountains of central Chile. We found that the metabolism of P. parvula was similar to other Theraphosidae and low compared to other arthropods. Carbon dioxide production and evaporative water loss increased with temperature, particularly at 40 degrees C. The total evaporative water loss at 40 degrees C increased dramatically to about 10 times that found with the lower temperatures. Thus, 40 degrees C will be the limit temperature for this species after which evaporative water loss starts to become damaging, so it has to avoid it. The exposition to hypercapnic environments had as a consequence an increase in evaporative water loss and the involvement of the book lungs in this loss was about 60%. The possibility of losing water could condition this species to seek temperate and oxygenated shelters under rocks.

Transitions in insect respiratory patterns are controlled by changes in metabolic rate.

We examined the respiratory patterns of Rhodnius prolixus and Gromphadorhina portentosa as metabolic rates varied with temperature to determine whether insects transition from discontinuous (DGC), cyclical and continuous respiration as a response to increasing aerobic demand. Using flow through respirometry we: (1) determined the effects of temperature on metabolic rate; (2) objectively defined periods of spiracular closure; (3) observed whether there was a correlation between metabolic rate and length of spiracular closure. At low temperatures both species exhibit lengthy periods of spiracular closure reflecting a discontinuous respiratory pattern. As metabolic rate increased, periods of spiracular closure decreased and insects displayed a more cyclical pattern of respiration. As metabolic rates increased even further under the highest experimental temperatures, periods of spiracular closure decreased even more and a continuous respiratory pattern was employed by both species. Our results suggest that the three described respiratory patterns in insects are not distinct but are instead a continuum of respiratory responses driven by the metabolic demand experienced by the insect.