Tolerance of three fungal species to lithium and cobalt: Implications for bioleaching of spent rechargeable Li-ion batteries.

AIMS: This paper aims to quantify the growth and organic acid production of Aspergillus niger, Penicillium chrysogenum and Penicillium simplicissimum when these fungi are exposed to varying levels of lithium (Li) and cobalt (Co). The study also tests whether pre-exposing the fungi to these metals enables the fungi to develop tolerance to Li or Co. METHODS AND RESULTS: When cultures of A. niger, P. chrysogenum or P. simplicissimum were exposed to 250 mg l-1 of Li or Co, biomass production and excretion of organic acids were significantly inhibited after 5 days of growth compared to cultures grown in the absence of these metals. Pre-exposing cultures of A. niger to 250 mg l-1 of Li or Co for 20 days significantly increased biomass production when the fungus was subsequently sub-cultured into 250 or 500 mg l-1 of Li or Co. However, pre-exposure of P. chrysogenum or P. simplicissimum to 250 mg l-1 of Li or Co for 20 days did not increase biomass production. CONCLUSIONS: Aspergillus niger, but not the Penicillium species, developed tolerance to Li and to Co during the 20-day pre-exposure period. Therefore, processes that utilize fungal bioleaching with A. niger to mobilize and recover valuable metals such as Li or Co should consider a pre-exposure step for fungi to improve their tolerance to metal toxicity. SIGNIFICANCE AND IMPACT OF THE STUDY: Fungi may have the ability to extract valuable metals such as Li and Co from spent rechargeable batteries. However, the toxicity of the extracted metals can inhibit fungal growth and organic acid production. Pre-exposure to metals may alleviate toxicity for some fungal species. This knowledge can be used to improve the design of bioleaching protocols, increasing the potential for fungal bioleaching to become an economical and environmentally friendly method of recovering Li and Co from spent batteries.

Decontaminating N95 and SN95 masks with ultraviolet germicidal irradiation does not impair mask efficacy and safety.

Inadequate supply of filtering facepiece respirators (FFRs) for healthcare workers during a pandemic such as the novel coronavirus outbreak (SARS-CoV-2) is a serious public health issue. The aim of this study was to synthesize existing data on the effectiveness of ultraviolet germicidal irradiation (UVGI) for N95 FFR decontamination. A systematic review (PROSPERO CRD42020176156) was conducted on UVGI in N95 FFRs using Embase, Medline, Global Health, Google Scholar, WHO feed, and MedRxiv. Two reviewers independently determined eligibility and extracted predefined variables. Original research reporting on function, decontamination, or mask fit following UVGI were included. Thirteen studies were identified, comprising 54 UVGI intervention arms and 58 N95 models. FFRs consistently maintained certification standards following UVGI. Aerosol penetration averaged 1.19% (0.70-2.48%) and 1.14% (0.57-2.63%) for control and UVGI arms, respectively. Airflow resistance for the control arms averaged 9.79 mm H2O (7.97-11.70 mm H2O) vs 9.85 mm H2O (8.33-11.44 mm H2O) for UVGI arms. UVGI protocols employing a cumulative dose >20,000 J/m2 resulted in a 2-log reduction in viral load. A >3-log reduction was observed in seven UVGI arms using >40,000 J/m2. Impact of UVGI on fit was evaluated in two studies (16,200; 32,400 J/m2) and no evidence of compromise was found. Our findings suggest that further work in this area (or translation to a clinical setting) should use a cumulative UV-C dose of 40,000 J/m2 or greater, and confirm appropriate mask fit following decontamination.

Cáncer en quiste tirogloso, con tiroides agenésica y nódulo ectópico. Caso clínico

Introducción: La glándula tiroides tiene su origen embriológico en la base de la lengua, desde donde desciende al cuello. Este proceso migratorio puede detenerse o continuar más allá, dando diferentes cuadros de tiroides ectópica. El quiste tirogloso es la alteración embriológica más frecuente en el cuello, pudiendo desarrollar cáncer como una complicación rara. Caso clínico: Paciente de 21 años con aumento de volumen cervical, se diagnostica quiste tirogloso, la biopsia identifica cáncer papilar en el quiste. Se decide completar tiroidectomía, se objetiva agenesia de glándula. Ante respuesta bioquímica incompleta se realiza cintigrama que identifica nódulo retrolingual, el cual es resecado. Discusión: La resección del quiste tirogloso se debe realizar según la descripción de Sistrunk para evitar recidivas. La historia natural del cáncer en quiste tirogloso es bastante menos conocida y podría tener un peor pronóstico que el cáncer tiroideo habitual. Existen grupos que defienden la necesidad de completar tiroidectomía y, eventualmente, realizar disecciones cervicales como parte de su manejo. Conclusión: El cáncer de quiste tirogloso es una patología infrecuente, Existen diferentes lineas de manejo que se discuten en la literatura. Aún el análisis individualizado de los pacientes en comités multidisciplinario de expertos es la conducta sugerida.

Introduction: The thyroid gland has its embryological origin from the base of the tongue, where it descends to the neck. This migratory process can stop early or continue beyond, giving rise to differents cases of ectopic thyroid. The thyroglossal cyst is the most frequent embryological alteration in the neck, and it can develop cancer as a rare complication. Clinical case: A 21 year old patient with a cervical volume increase is diagnosed a thyroglossal cyst. Biopsy identifies papilary cancer in the cyst. It is decided to complete de thyroidectomy, and agenesis of the gland is observed. Due to incomplete biochemical response, a scintigram is performed, wich identifies a retrolingual nodule that is resected. Discussion: The resection of the thyroglossus cyst should be performed according to the description of Sistrunk to avoid recurrence. The natural history of cancer in the thyroglossal cyst is much less known and could have a worst prognosis than usual thyroid cancer. Some groups advocate for the need to complete a thyroidectomy and eventually perform cervical dissections as part of its management. Conclusion: The cancer on a thyroglossal cyst is a rare pathology. There are diferents management approaches that are discussed in the literature. However, an individualized analysis of patients in multidisciplinary expert committees it still the suggested aproach.

Determination of wild animal sources of fecal indicator bacteria by microbial source tracking (MST) influences regulatory decisions.

Fecal indicator bacteria (FIB) are used to assess fecal pollution levels in surface water and are among the criteria used by regulatory agencies to determine water body impairment status. While FIB provide no information about pollution source, microbial source tracking (MST) does, which contributes to more direct and cost effective remediation efforts. We studied a watershed in Florida managed for wildlife conservation that historically exceeded the state regulatory guideline for fecal coliforms. We measured fecal coliforms, enterococci, a marker gene for avian feces (GFD), and a marker gene for human-associated Bacteroides (HF183) in sediment, vegetation, and water samples collected monthly from six sites over two years to: 1) assess the influence of site, temporal factors, and habitat (sediment, vegetation, and water) on FIB and MST marker concentrations, 2) test for correlations among FIB and MST markers, and 3) determine if avian feces and/or human sewage contributed to FIB levels. Sediment and vegetation had significantly higher concentrations of FIB and GFD compared to water and thus may serve as microbial reservoirs, providing unreliable indications of recent contamination. HF183 concentrations were greatest in water samples but were generally near the assay limit of detection. HF183-positive results were attributed to white-tailed deer (Odocoileus virginianus) feces, which provided a false indication of human sewage in this water body. FIB and GFD were positively correlated while FIB and HF183 were negatively correlated. We demonstrated that birds, not sewage, were the main source of FIB, thus avoiding implementation of a total maximum daily load program (TMDL). Our results demonstrate that the concomitant use of FIB and MST can improve decision-making and provide direction when water bodies are impaired, and provides a strategy for natural source exclusion in water bodies impacted by wild animal feces.

Theory of polariton-mediated Raman scattering in microcavities.

We calculate the intensity of the polariton-mediated inelastic light scattering in semiconductor microcavities. We treat the exciton-photon coupling nonperturbatively and incorporate lifetime effects in both excitons and photons, and a coupling of the photons to the electron-hole continuum. Taking the matrix elements as fitting parameters, the results are in excellent agreement with measured Raman intensities due to optical phonons that are resonant with the upper polariton branches in II-VI microcavities with embedded CdTe quantum wells.

Luteinizing hormone pulse frequency is increased by arginine infusion in prepubertal sheep.

Puberty in sheep is initiated by a complex neuroendocrine interplay which cascades into an increased LH pulsatility at this time. Blood-borne amino acids have been proposed as metabolic signals for the stimulation of GnRH/LH secretion, a mandatory requirement for pubertal onset. In previous experiments we have demonstrated that a 1 h infusion of L-arginine (ARG) was capable of stimulating the LH secretion in prepubertal ewes. The aim of the present study was to further examine the effect of an intravenous infusion of ARG on LH secretion. Prepubertal ewes were infused for 6 h with 15 (Group ARG15, n = 5) or 30 g (Group ARG30, n = 5) of L-ARG dissolved in 500 mL saline (pH 7.4), while saline was administered as control (Group S, n = 5). Since ARG is metabolized to ornithine (ORN), equimolar doses of L-ORN were additionally tested (Group ORN12 and ORN24, n = 5, respectively). Blood samples were obtained at 15 minute intervals during and after experimental infusions to characterize the LH pulsatile secretion. The resulting hormone data arrays were searched for significant fluctuations by the PULSAR program. The LH pulse frequency was found to be higher in groups of ARG treated than in saline or ORN infused sheep during the 6-h infusion period: 5.6 +/- 1.0 (ARG15) vs. 5.0 +/- 0.5 (ARG30) vs. 2.0 +/- 0.9 (S, p < 0.01) vs. 3.4 +/- 0.9 (ORN12) vs. 3.4 +/- 0.9 pulses/6 h (ORN24, p < 0.05). The total number of pulses was higher in ARG infused lambs than in saline or ORN infused animals: 11.2 +/- 1.2 (ARG15) vs. 10 +/- 1.1 (ARG30) vs. 13.8 +/- 1.4 (S) vs. 5.8 +/- 1.7 (ORN12) vs. 5.8 +/- 2.0 pulses/12h (ORN24), respectively. The LH mean secretion was comparable during both 6-h periods in all groups. Results of our experiments demonstrate increased LH pulse frequencies during ARG infusions, suggesting an action of ARG to stimulate hypothalamic GnRH release. Thus, ARG may be a critical determinant for enhanced LH pulsatility as a prerequirement for the onset of puberty in the sheep.

Pituitary responsiveness to diurnal and nocturnal GnRH pulses in melatonin-treated ewe lambs.

It has been shown that oral administration of melatonin to Suffolk ewe lambs, from 10 weeks of age onwards, advances the onset of puberty compared with control lambs maintained under the same natural photoperiod. Luteinizing hormone (LH) pulse frequency at 20 and 26 weeks of age was unchanged by melatonin. However, LH pulse amplitudes greater than 1 ng mL(-1) were consistently observed in melatonin-treated lambs, suggesting either a high responsiveness of the pituitary gland to endogenous gonadotrophin-releasing hormone (GnRH) pulses, or a large amount of GnRH released by each pulse. The purpose of the present study was to assess the pituitary responsiveness to six diurnal and six nocturnal exogenous pulses of GnRH (10 ng kg(-1) bodyweight) in melatonin-treated ewe lambs (3 mg melatonin daily at 1600 hours, from 10 weeks of age; n = 5) and control lambs of the same age (n = 5), born in the spring and kept under natural photoperiod. Pulses of GnRH were given intravenously at 60-min intervals by means of an indwelling jugular catheter from 0900 to 1400 hours and from 2100 to 0200 hours to ewe lambs of 20 and 26 weeks of age. Blood samples were collected at 10-min intervals using a contralateral jugular vein catheter from 1 h before and up to 1 h after the last GnRH pulse. The difference (delta) between plasma LH concentrations at 0 min and the greatest concentration of LH after each GnRH pulse was calculated and compared in the same group. The total area under the GnRH response curve (AUC) was also calculated and compared within and between the groups. The AUC of melatonin-treated lambs (66.1 +/- 5.94 and 52.24 +/- 7.42 ng mL(-1)/6 h, diurnal and nocturnal respectively) was greater than that of control lambs (39.42 +/- 4.29 and 32.82 +/- 3.6 ng mL(-1)/6 h diurnal and nocturnal respectively; P<0.05) at 20 weeks of age. At 26 weeks of age, only the diurnal total AUC was greater in melatonin-treated lambs than in control lambs (60.17 +/- 7.98 and 29.8 +/- 5.02 ng mL(-1)/6 h respectively; P<0.05). Delta LH concentrations in response to the first diurnal pulse of GnRH were greater than those in response to the fifth diurnal GnRH pulse (P<0.05) in melatonin-treated lambs of 20 weeks of age. Also, the delta LH concentrations in response to the first three diurnal GnRH pulses were greater than to the last three nocturnal pulses of GnRH (P<0.05). Delta LH concentrations were greater in response to the second diurnal pulse of GnRH than to the last three diurnal GnRH pulses, and greater than the responses to the first and the last four nocturnal GnRH pulses (P<0.05), at 26 weeks of age in melatonin-treated lambs. The response to nocturnal pulses of GnRH was similar. In control lambs, the responses to diurnal and nocturnal GnRH pulses were similar at 20 and 26 weeks of age. These results suggest that melatonin enhances the pituitary responsiveness to GnRH pulses in ewe lambs.

Effects of winter supplementation and antiparasite treatment on the productive performance of milk herd in the central-south region of Chile.

During the winter of 1994, a survey of productive and reproductive parameters was undertaken in the south-central part of Chile (8th Region) on 71 cows provided by four small farms with low production (< 3000 l/year). A low food intake was recorded (8.6 +/- 0.2-12.4 +/- 0.2 kg DM/day) and, as a result, the cows calved with poor body condition score (1.9 +/- 0.04 points on the scale of one-to-five, had milk production between 10.5 +/- 0.4 and 12.8 +/- 0.6 l/day, had a delayed start of ovulatory activity (78.2 +/- 4.6 days) and an interval between calving and conception of 120.3 +/- 4.6 days. In addition, low levels of packed cell volume (PCV) and hemoglobin (HEM) were found, which were considered to be a combined effect of low feed ingestion and parastic infection by Fasciola hepatica. To improve the productive and reproductive parameters, treatments were undertaken in three of the four small farms; a parasiticide treatment was used against the F. hepatica at the beginning of the winter and the availability of forage was increased via the use of supplementary green oats. Spring crops were also cultivated: corn for silage and oats with peas to make hay. The antiparasite treatment and supplementation of forage was associated with better body condition score at calving, improved hematological parameters, increased milk production (17%), reduced number of days to conception (120 vs. 91) and increased conception rate at first service (36 vs. 60%). In the fourth small farm where no interventions were undertaken, the parameters obtained during 1994 remained unchanged.

Effect of arginine and ornithine infusions on luteinizing hormone secretion in prepubertal ewes.

Although activation of the hypothalamic GnRH pulse generator is known to initiate the onset of puberty in immature animals, the metabolic cues by which information about the stage of body growth and development are translated into central nervous activity remain obscure. In the present study, the function of L-arginine (ARG) or L-ornithine (ORN) as promoters of pulsatile LH secretion was investigated in 2-mo-old prepubertal ewes. Suffolk ewe lambs (n = 17) fitted with intrajugular catheters were divided into three groups. Saline (200 mL) was infused for 1 h into all lambs. In Group 1, saline infusion was continued for another hour. In Group 2, 200 mL of an ARG solution (350 mM, pH 7.4) was infused for 1 h, and in Group 3, ORN was infused (200 mL, 350 mM, pH 7.4) for 1 h. Blood samples were collected at 15-min intervals from 60 min before until 285 min after the end of infusions. The Pulsar program was used to identify significant LH episodes during 285 min after infusions. Mean LH concentrations during the 285-min period after infusion were greater (P < .05) in Group 2 than in Groups 1 and 3. The mean LH pulse frequencies and amplitudes did not differ among the groups. However, in lambs infused with ARG, 13 of their 17 LH pulses had amplitudes > 1 ng/mL, whereas in control ewes only 5 of 20 pulses had amplitudes > 1 ng/mL. All of the ARG-infused ewes had two or more LH pulses with amplitudes > 1 ng/mL; only 1 of 6 control lambs had two pulses. Results indicate that ARG stimulates LH secretion in prepubertal ewes.

Variables que afectan la satisfacción con la alimentación según nivel socioeconómico: un estudio exploratorio en el sur de Chile / Variables affecting food satisfaction according to socioeconomic status: an exploratory study in southern Chile

In order to identify variables that influence in food satisfaction for people belonging to different socioeconomic status (SES) in southern Chile, a survey was administered to a sample of 400 people living in the major cities of this region. The questionnaire included the SWFL (Satisfaction with Food-related Life) scale and the IQLRH (Index of Quality of Life Related to Health). Demographic characteristics and dietary habits were also consulted. Four ordinal logit models were proposed, where the dependent variable was satisfaction with food-related life, considering the total sample and three subsamples: medium and medium-high strata (ABC1), medium-medium (C2) and medium-low (C3), low (D) and very low (E) as a whole. The four models were significant (p<0.001), but differed in the explanatory variables that were significant. Regardless of SES, satisfaction with food-related life decreases if the person does not have a good perception of their own health. Other variables that influence satisfaction with food-related life, which differed according to the SES, are related to the gender, the family composition, the time available for family dining, frequency of consumption of meat and use of fast food outlets and the restriction of alcohol consumption.

Con el objetivo de identificar variables que influyen en la satisfacción con la alimentación en personas pertenecientes a distintos niveles socioeconómicos (NSE) del sur de Chile, se aplicó una encuesta a 400 personas residentes en las principales ciudades de esta parte del país. El cuestionario incluyó la escala SWFL (Satisfaction with Food-related Life) y el Indice de Calidad de Vida relativo a la Salud (ICVRS). Se consultaron características demográficas y hábitos alimentarios. Se plantearon cuatro modelos logit ordinales, en los cuales la variable dependiente fue la satisfacción con la alimentación, considerando la muestra total y tres submuestras: estratos alto y medio-alto (ABC1), medio-medio (C2) y en conjunto los niveles medio-bajo (C3), bajo (D) y muy bajo (E). Los cuatro modelos resultaron significativos (p<0,001), pero difirieron en las variables explicativas significativas. Independientemente del NSE, la satisfacción con la alimentación disminuye si la persona no tiene una buena auto percepción de su salud. Otras variables que influyen en la satisfacción con la alimentación, que difirieron según el NSE, corresponden al género, composición de la familia, tiempo disponible para cenar en familia, frecuencia de consumo de carne y en locales de comida rápida y, la restricción del consumo de alcohol.

Effects of interactions in transport through Aharonov-Bohm-Casher interferometers.

We study the conductance through a ring described by the Hubbard model (such as an array of quantum dots), threaded by a magnetic flux and subject to Rashba spin-orbit coupling (SOC). We develop a formalism that is able to describe the interference effects as well as the Kondo effect when the number of electrons in the ring is odd. In the Kondo regime, the SOC reduces the conductance from the unitary limit, and, in combination with the magnetic flux, the device acts as a spin polarizer.

Satisfacción con la alimentación en personas mapuches de la región de la Araucania, Chile / Food-related life satisfaction in mapuches from the Araucanía region, Chile

In order to identify variables which have an influence on satisfaction with food-related life among mapuches a survey was applied to 400 mapuche subjects in the Araucanía Region. The questionnaire included the SWFL (Satisfaction with Food-related Life) scale. It was found that 39.5% were satisfied and 332% extremely satisfied with their food-related life. A multinomial probit model was proposed in which the dependent variable was food-satisfaction, which resulted significant (p<0.01) overall. The probability of high food-related satisfaction increases as fewer people live in the subject's household, more is spent on food, children express their opinion aboutfoodstuffs, he/she consumes "catutos" (a mapuche food), aged 55 or over, not widowed, performs regular exercise, tries not to eat industrialized foods, but does not try to eat foods without additives. Food-related satisfaction in mapuche persons in the Araucanía Region is related to demographic, feeding and life-style variables.

Con el objetivo de identificar variables que influyen en la satisfacción con la alimentación en personas mapuche, se aplicó una encuesta a 400 sujetos de esta etnia en la Región de La Araucanía. El cuestionario incluyó la escala SWFL (Satisfaction with Food-related Life). Se obtuvo que el 39,5% está satisfecho y el 33,2% extremadamente satisfecho con su alimentación. Se planteó un modelo probit multinomial en que la variable dependiente fue la satisfacción con la alimentación, el cual resultó significativo (p<0,01) en su conjunto. La probabilidad de una alta satisfacción con la alimentación aumenta en la medida que en el hogar del individuo viven menos personas, se gasta más en alimentación, los niños opinan respecto a los alimentos, consume catutos, tiene 55 años de edad o más, no es viudo, realiza regularmente ejercicio, procura no comer alimentos industrializados, pero no procura comer alimentos sin aditivos. La satisfacción con la alimentación en mapuche de La Araucanía se relaciona con variables demográficas, alimentación y estilo de vida.

Tipologias de consumidores según el estilo de vida en relación a la alimentación: un estudio exploratorio en el sur de Chile / Consumer typology according to food-related lifestyle: an exploratory study in southern Chile

Con el objetivo de distinguir y caracterizar tipologías de consumidores en base a su estilo de vida en relación a la alimentación en forma exploratoria, se aplicó una encuesta a una muestra de 316 personas de las principales ciudades del sur del Chile. El instrumento de recogida de información incluyó una adaptación del cuestionario de estilos de vida en relación a la alimentación (FRL) y la escala SWFL (Satisfaction with Food-related Life). Mediante análisis cluster se distinguieron tres tipologías principales. La mayoritaria (30,1%) prefiere alimentos fáciles de preparar, planifica su alimentación y mantiene sus hábitos alimentarios. La segunda (17,4%) disfruta de salir a comer fuera y de cenas con amigos en casa, pero prefieren alimentos conocidos, son planificados y constantes en sus hábitos de alimentación. La tercera tipología (14,6%) disfruta compartir con amigos una comida, pero no le gusta cocinar ni utilizar alimentos de fácil preparación. Las tipologías presentaron distinto perfil demográfico. Difirieron en la frecuencia de consumo de alimentos en el hogar y en la frecuencia de comidas fuera del hogar. Se evidenciaron diferencias en la restricción de comidas y aderezos por motivos de salud y en la satisfacción con su alimentación.

With the aim of characterizing consumer typologies on the basis offood-related lifestyle in an exploratory manner, a survey was applied to a sample of 316 people in the main cities of southern Chile. The instruments for collecting data included an adaptation of the Food-related Lifestyle (FRL) questionnaire and the Satisfaction with Food-related Life (SWFL) scale. Three main typologies were distinguished using a cluster analysis. The majority (30.1 %) preferred easily prepared food, planned their diet and maintained their eating habits. The second group (17.4%) enjoyed eating out and dinners with friends at home, but they preferred known foods,and were programmed and constant in their eating habits. The third typology (14.6%) enjoyed sharing a meal with friends, but did not like cooking or using easy-to-prepare foods. The typologies displayed different profiles based on demographics. They differed in the food consumption frequency in the home and in the frequency of eating out. Differences were observed in the restriction of meals and dressings for health reasons and in the satisfaction with their food-related life.

Control ecográfico post inserción de dispositivo intrauterino / Ultrasound control post insertion of intrauterine device

INTRODUCCIÓN: Los dispositivos intrauterinos (DIU) son métodos de anticoncepción reversible, ampliamente usados en el mundo. Se estima que 120 millones de mujeres usan un DIU en el mundo como método anticonceptivo. OBJETIVO: Evaluar los factores de riesgo que puedan relacionarse con una incorrecta inserción del DIU. MÉTODO: 93 pacientes de un Centro de Salud Familiar de la ciudad de Talca, Chile. Utilizando tablas de contingencia se calcularon diferentes medidas de asociación y se compararon los casos de DIU mal posicionado con los casos con uno o más factores de riesgo identificados. RESULTADOS: Se encontró una incidencia de DIU incorrectamente posicionado de un 15,8%, de los cuales hubo un 2,1% de perforación uterina, 2,1% para DIU incrustado y 11,8% para DIU descendido. Se identificaron como factores de riesgo de DIU incorrectamente posicionado la cicatriz de cesárea (RR: 2,31), inserción dificultosa (RR: 3,31) y opinión de un resultado dudoso (RR: 3,64), con una sensibilidad de 73,3%. CONCLUSIONES: La ecotomografía transvaginal es una herramienta crucial para la confirmación de una correcta inserción del DIU y debería ser un examen de rutina ante la presencia de cualquiera de los factores de riesgo identificados.

BACKGROUND: Intrauterine devices (lUDs) are reversible birth control methods that are widely used throug-hout the world. It is estimated that 120 million women use an IUD in the world as a contraceptive. AIM: To assess the risk factors that may relate to incorrect insertion of the IUD. METHODS: The sample included 93 patients of a Family Health Center, Talca, Chile. Using contingency tables, various measures of association were calculated, and the cases of incorrectly positioned IUD were compared with the cases where one or more risk factors were identified. RESULTS: We found an incidence of 15.8% of incorrectly positioned IUD, of which 2.1% presented with uterine perforation, 2.1% with embedment of the IUD and 11.8% with a descended IUD. We identified the following risk factors for incorrectly positioned IUD: cesarean section (RR: 2.31), difficulty on insertion (RR: 3.31) and practitioner's opinión of an uncertain result (RR: 3.64), with a sensitivity of 73.3%. CONCLUSIONS: Transvaginal ultrasound is a crucial tool for confirmation of proper insertion of an IUD and should be considered a routine examination when any of the identified risk factors are present.

Secretory pattern of leptin and LH during lactational amenorrhoea in breastfeeding normal and polycystic ovarian syndrome women.

Several studies have suggested that leptin modulates hypothalamic-pituitary-gonadal axis function. A synchronicity of LH and leptin pulses has been described in healthy women and in patients with polycystic ovarian syndrome (PCOS), suggesting that leptin may modulate the episodic secretion of LH. The aim of the present investigation was to assess the episodic fluctuations of circulating LH and leptin during lactational amenorrhoea in fully breastfeeding normal and PCOS women at 4 and 8 weeks postpartum, in order to establish LH-leptin interactions in the reactivation of the gonadal axis during this period. Six lactating PCOS patients and six normal lactating women of similar age and body mass index were studied. During a 12 h period on the 4th and 8th weeks postpartum, blood samples were collected at 10 min intervals for 12 h (22:00-10:00). Serum LH and leptin concentrations were measured in all samples. For pulse analysis, the cluster algorithm was used. To detect an interaction between LH and leptin pulses, an analysis of co-pulsatility was employed. LH concentrations tended to increase in both groups between the 4th and 8th weeks postpartum; however, serum leptin concentrations were not modified. Leptin pulse frequencies were similar at the 4th and 8th weeks postpartum, and did not differ between groups. Moreover, leptin pulse frequency was higher than LH pulse frequency in both groups, and in the two study periods. There was no synchronicity between LH and leptin pulses, and there were no increments in leptin concentration during the night. The fact that leptin concentrations were not modified and no synchronicity between LH and leptin pulses was observed suggests that, during lactational amenorrhoea, circulating leptin is probably not involved as a primary signal in promoting the reactivation of pulsatile LH secretion.

Rank dependent seasonal levels of IGF-1, cortisol and reproductive hormones in male pudu (Pudu puda).

We tested the following hypothesis: when two pudu males share a single pen throughout the year, the dominant animal will have a higher level of IGF-1 than its subordinate pen mate, particularly during the period of increased social friction (e.g. rut and establishment of territories). To test this hypothesis, we used data from six adult males maintained at the University of Concepión, Chile (latitude 36.6 degrees S), and analysed them from the males' dominance point of view. Two males plus eight to ten females were kept in one pen and although we did not specifically measure dominance, the rank position was obvious from frequent encounters between the bucks. Three consecutive blood samples were taken monthly over the period of 1 year. In addition to IGF-1, we also analysed seasonal levels of testosterone, cortisol, prolactin, LH and FSH. The analysis revealed that IGF-1 levels of dominant males were significantly higher than those of subordinate males from September to November (the second part of the antler growing period and time of establishing territories). Testosterone levels were higher and FSH levels were lower in dominant males during the rut. Levels of prolactin were higher in dominant animals in November (summer). Cortisol and LH did not show any significant differences between dominant and subordinate males. This data provides the first evidence indicating the possible link between dominance and blood levels of IGF-1. The functional explanation of such links is discussed.

Cardiac valve calcification in haemodialysis patients: role of calcium-phosphate metabolism.

BACKGROUND: Cardiac valve calcification (VC) has been detected with increased frequency in haemodialysis (HD) patients, making it necessary to determine the potential pathogenic factors in uraemic patients. METHODS: A total of 92 chronic HD patients (39 female, 53 male) and 92 age and gender-matched nondialysis control subjects were evaluated by echocardiography and a severity score for VC was determined. Calcium phosphate metabolism was evaluated at the beginning of haemodialysis. RESULTS: We found a greater prevalence of VC in dialysis patients than in normal patients (mitral annulus 44.5% vs 10%, P = 0.02; aortic annulus 52% vs 4.3%, P = 0.01). HD patients with mitral calcification were found to be older than patients without calcification, were on long-term renal replacement therapy, had longer duration of predialysis arterial hypertension, had greater values of the highest value of mean calcium phosphate product in 6 successive months (CaxP) and the highest absolute value of calcium-phosphate product (CaxPmax). We also found a positive correlation between calcification score, age, and CaxP. No correlation was found between actual VC and arterial hypertension or parathyroid hormone. Multiple stepwise regression analysis selected age and CaxP as the most predictive parameters for mitral calcification (r = 0.47). Mitral calcification was associated more frequently with rhythm and cardiac conduction defects, valvular insufficiency and with peripheral vascular calcification. Aortic calcification was correlated with age (r = 0.42) and longer duration of predialysis arterial hypertension. CONCLUSION: Our study confirmed an increased prevalence of VC in HD patients and selected age and calcium phosphate product as the most predictive parameters. These findings support careful monitoring of calcium metabolism beginning at the early stages of end-stage renal failure to reduce the risk of heart disease.