[Regarding pandemics: Ibn Jatima from Almería anticipates the physiopathological concept of multi-organ failure in the 14th century]. / A propósito de pandemias: Ibn Jatima de Almería anticipa el concepto fisiopatológico de fallo multiorgánico en el siglo XIV.

In 1348, a pandemic known as Black Death devastated humanity and changed social, economic and geopolitical world order, as is the current case with SARS-CoV-2 coronavirus. The doctor of the Nasrid Kingdom of Granada, Ibn Jatima from Almeria, wrote Treatise on the Plague, in which it may be found epidemiological and clinical similarities between both plagues. In the context of Greco-Arab medicine, he discovered respiratory and contact contagion of Pestis and attributed its physiopathology to a lack of pulmonary cooling of the innate heat, generated in the heart and carried by the blood humor. The process described was equivalent to the oxygen transport system. Furthermore, it was supposed to generate toxic residues, such as free radicals, leading to an irreversible multiple organ failure (MOF), considered a mortality factor as in Covid-19. Due to its similitude, it would be the first antecedent of the MOF physiopathological concept, a finding that enriches the scientific and historical heritage of our clinical specialty.

A propósito de pandemias: Ibn Jatima de Almería anticipa el concepto fisiopatológico de fallo multiorgánico en el siglo XIV / Regarding pandemics: Ibn Jatima from Almería anticipates the physiopathological concept of multi-organ failure in the 14th century

En el año 1348 una pandemia de la llamada «peste negra» asoló la humanidad y cambió el orden social, económico y geopolítico del mundo, tal como sucede actualmente con la causada por el coronavirus SARS-CoV-2. El médico del reino nazarí de Granada, Ibn Jatima de Almería, escribió un Tratado sobre la peste en el cual se encuentran semejanzas epidemiológicas y clínicas entre ambas plagas. Así, dentro del contexto de la medicina greco-árabe, descubrió el contagio respiratorio y por contacto de la peste, y atribuyó su fisiopatología a una insuficiente refrigeración pulmonar del calor innato generado en el corazón y vehiculizado por el humor sanguíneo, equivalente al sistema de trasporte de oxígeno, lo cual generaba residuos tóxicos, como los radicales libres, que abocaba a un fallo multiorgánico (FMO) irreversible, factor de mortalidad como en la Covid-19. Por su similitud, sería el primer antecedente conocido del concepto fisiopatológico de FMO, hallazgo que enriquece nuestro patrimonio científico-histórico de la especialidad. (AU)

In 1348, a pandemic known as Black Death devastated humanity and changed social, economic and geopolitical world order, as is the current case with SARS-CoV-2 coronavirus. The doctor of the Nasrid Kingdom of Granada, Ibn Jatima from Almeria, wrote Treatise on the Plague, in which it may be found epidemiological and clinical similarities between both plagues. In the context of Greco-Arab medicine, he discovered respiratory and contact contagion of Pestis and attributed its physiopathology to a lack of pulmonary cooling of the innate heat, generated in the heart and carried by the blood humor. The process described was equivalent to the oxygen transport system. Furthermore, it was supposed to generate toxic residues, such as free radicals, leading to an irreversible multiple organ failure (MOF), considered a mortality factor as in Covid-19. Due to its similitude, it would be the first antecedent of the MOF physiopathological concept, a finding that enriches the scientific and historical heritage of our clinical specialty. (AU)

Regarding pandemics: Ibn Jatima from Almería anticipates the physiopathological concept of multi-organ failure in the 14th century.

In 1348, a pandemic known as Black Death devastated humanity and changed social, economic and geopolitical world order, as is the current case with SARS-CoV-2 coronavirus. The doctor of the Nasrid Kingdom of Granada, Ibn-Jatima from Almeria, wrote "Treatise on the Plague", in which it may be found epidemiological and clinical similarities between both plagues. In the context of Greco-Arab medicine, he discovered respiratory and contact contagion of Pestis and attributed its physiopathology to a lack of pulmonary cooling of the innate heat, generated in the heart and carried by the blood humor. The process described was equivalent to the oxygen transport system. Furthermore, it was supposed to generate toxic residues, such as free radicals, leading to an irreversible multiple organ failure (MOF), considered a mortality factor as in Covid-19. Due to its similitude, it would be the first antecedent of the MOF physiopathological concept, a finding that enriches the scientific and historical heritage of our clinical specialty.

Assessment of climate change effects on mountain ecosystems through a cross-site analysis in the Alps and Apennines.

Mountain ecosystems are sensitive and reliable indicators of climate change. Long-term studies may be extremely useful in assessing the responses of high-elevation ecosystems to climate change and other anthropogenic drivers from a broad ecological perspective. Mountain research sites within the LTER (Long-Term Ecological Research) network are representative of various types of ecosystems and span a wide bioclimatic and elevational range. Here, we present a synthesis and a review of the main results from ecological studies in mountain ecosystems at 20 LTER sites in Italy, Switzerland and Austria covering in most cases more than two decades of observations. We analyzed a set of key climate parameters, such as temperature and snow cover duration, in relation to vascular plant species composition, plant traits, abundance patterns, pedoclimate, nutrient dynamics in soils and water, phenology and composition of freshwater biota. The overall results highlight the rapid response of mountain ecosystems to climate change, with site-specific characteristics and rates. As temperatures increased, vegetation cover in alpine and subalpine summits increased as well. Years with limited snow cover duration caused an increase in soil temperature and microbial biomass during the growing season. Effects on freshwater ecosystems were also observed, in terms of increases in solutes, decreases in nitrates and changes in plankton phenology and benthos communities. This work highlights the importance of comparing and integrating long-term ecological data collected in different ecosystems for a more comprehensive overview of the ecological effects of climate change. Nevertheless, there is a need for (i) adopting co-located monitoring site networks to improve our ability to obtain sound results from cross-site analysis, (ii) carrying out further studies, in particular short-term analyses with fine spatial and temporal resolutions to improve our understanding of responses to extreme events, and (iii) increasing comparability and standardizing protocols across networks to distinguish local patterns from global patterns.

Growth hormone protects against kainate excitotoxicity and induces BDNF and NT3 expression in chicken neuroretinal cells.

There is increasing evidence to suggest a beneficial neuroprotective effect of growth hormone (GH) in the nervous system. While our previous studies have largely focused on retinal ganglion cells (RGCs), we have also found conclusive evidence of a pro-survival effect of GH in cells of the inner nuclear layer (INL) as well as a protective effect on the dendritic trees of the inner plexiform layer (IPL) in the retina. The administration of GH in primary neuroretinal cell cultures protected and induced neural outgrowths. Our results, both in vitro (embryo) and in vivo (postnatal), showed neuroprotective actions of GH against kainic acid (KA)-induced excitotoxicity in the chicken neuroretina. Intravitreal injections of GH restored brain derived neurotrophic factor (BDNF) expression in retinas treated with KA. In addition, we demonstrated that GH over-expression and exogenous administration increased BDNF and neurotrophin-3 (NT3) gene expression in embryonic neuroretinal cells. Thus, GH neuroprotective actions in neural tissues may be mediated by a complex cascade of neurotrophins and growth factors which have been classically related to damage prevention and neuroretinal tissue repair.

Synthesis and Biological Evaluation of Ru(II) and Pt(II) Complexes Bearing Carboxyl Groups as Potential Anticancer Targeted Drugs.

The synthesis and characterization of Pt(II) (1 and 2) and Ru(II) arene (3 and 4) or polypyridine (5 and 6) complexes is described. With the aim of having a functional group to form bioconjugates, one uncoordinated carboxyl group has been introduced in all complexes. Some of the complexes were selected for their potential in photodynamic therapy (PDT). The molecular structures of complexes 2 and 5, as well as that of the sodium salt of the 4'-(4-carboxyphenyl)-2,2':6',2″-terpyridine ligand (cptpy), were determined by X-ray diffraction. Different techniques were used to evaluate the binding capacity to model DNA molecules, and MTT cytotoxicity assays were performed against four cell lines. Compounds 3, 4, and 5 showed little tendency to bind to DNA and exhibited poor biological activity. Compound 2 behaves as bonded to DNA probably through a covalent interaction, although its cytotoxicity was very low. Compound 1 and possibly 6, both of which contain a cptpy ligand, were able to intercalate with DNA, but toxicity was not observed for 6. However, compound 1 was active in all cell lines tested. Clonogenic assays and apoptosis induction studies were also performed on the PC-3 line for 1. The photodynamic behavior for complexes 1, 5, and 6 indicated that their nuclease activity was enhanced after irradiation at λ = 447 nm. The cell viability was significantly reduced only in the case of 5. The different behavior in the absence or presence of light makes complex 5 a potential prodrug of interest in PDT. Molecular docking studies followed by molecular dynamics simulations for 1 and the counterpart without the carboxyl group confirmed the experimental data that pointed to an intercalation mechanism. The cytotoxicity of 1 and the potential of 5 in PDT make them good candidates for subsequent conjugation, through the carboxyl group, to "selected peptides" which could facilitate the selective vectorization of the complex toward receptors that are overexpressed in neoplastic cell lines.

[Proposing a physiological model for Emergency Department. Operating principles, classification of overcrowding and guidelines for redesign]. / Una propuesta de modelo fisiológico de servicio de urgencias hospitalario. Principios de funcionamiento, tipificación de la saturación y pautas para el rediseño.

The operation of Emergency Departments (ED) is determined by demand, their own organizational structures and the connection to other medical care levels. When these elements are not simultaneous, it hinders patient flow and decreases capacity, making it necessary to employ a systemic approach to the chain of emergency care as a single operational entity. With this theoretical orientation, we suggest a conceptual model similar to the physiological cardiac output, in which the preload is the demand, the contractile or flow pump is the organizational structure, the afterload is the hospital, the pre-ED valve is primary care and outpatient emergencies, and the post-ED valve is the diagnostic support services and the specialist consultants. Based on this theoretical approach we classify the different types of ED overcrowding and systematise its causes and the different waiting lists that it generates, which can help to redesign the service and avoid its saturation.

Una propuesta de modelo fisiológico de servicio de urgencias hospitalario. Principios de funcionamiento, tipificación de la saturación y pautas para el rediseño / Proposing a physiological model for Emergency Department. Operating principles, classification of overcrowding and guidelines for redesign

El funcionamiento de los servicios de urgencias hospitalarios (SUH) está determinado por la demanda, la estructura organizativa propia y la conexión con los otros niveles asistenciales. La asincronía entre estos elementos dificulta el flujo de pacientes y merma la capacidad, siendo necesario emplear un enfoque sistémico de la cadena asistencial urgente como una entidad funcional única. Con esta orientación presentamos un modelo teórico conceptual, similar al fisiológico del gasto cardíaco, en el que la precarga es la demanda, la bomba contráctil o de flujo la organización interna propia, la poscarga el hospital, la válvula pre-SUH la asistencia primaria y las urgencias extrahospitalarias, y la válvula pos-SUH los servicios de apoyo al diagnóstico y los especialistas consultores. A partir de dicha concepción se clasifican los distintos tipos de saturación del SUH, se sistematizan sus causas y las diferentes colas de espera que generan, lo cual puede ayudar al rediseño del servicio y a prevenir su saturación y colapso (AU)

The operation of Emergency Departments (ED) is determined by demand, their own organizational structures and the connection to other medical care levels. When these elements are not simultaneous, it hinders patient flow and decreases capacity, making it necessary to employ a systemic approach to the chain of emergency care as a single operational entity. With this theoretical orientation, we suggest a conceptual model similar to the physiological cardiac output, in which the preload is the demand, the contractile or flow pump is the organizational structure, the afterload is the hospital, the pre-ED valve is primary care and outpatient emergencies, and the post-ED valve is the diagnostic support services and the specialist consultants. Based on this theoretical approach we classify the different types of ED overcrowding and systematize its causes and the different waiting lists that it generates, which can help to redesign the service and avoid its saturation (AU)

Composición corporal en escolares de primaria y su relación con el hábito nutricional y la práctica reglada de actividad deportiva / Composição corporal em estudantes do ensino fundamental e sua relação com o hábito nutricional na prática regular de atividade física / Body composition in elementary school and its relationship with nutritional habits and formal practice sports activity

Objetivos. Presentar las relaciones encontradas en el primer año del estudio longitudinal de 6 años de duración entre la composición corporal, frecuencia de consumo de alimentos, nivel de actividad física y prevalencia de sobrepeso y obesidad en niños y niñas de 6 años. Método. Mensualmente se midió el peso y la talla, se calculó el índice de masa corporal (IMC) y se pasó un cuestionario de frecuencia de consumo de alimentos mediante el test Kidmed de adherencia a la dieta mediterránea y el cuestionario PAQ-C de actividad física. A partir de los datos de IMC se obtuvieron los valores correspondientes a la ecuación de regresión de Cole y los percentiles según las tablas del CDC de Atlanta y de la Fundación Orbegozo. Semestralmente se realizó una bioimpedancia monofrecuencia (BIA), cineantropometría completa y medición del gasto energético durante 2 días consecutivos con un calorímetro ArmBand. Resultados. Los principales hallazgos de este primer año son los siguientes: los datos obtenidos por BIA y por cineantropometría muestran una buena correlación, los datos del cuestionario Kidmed no muestran correlación con los datos antropométricos ni con el IMC, los datos del PAQ-C y la calorimetría muestran un mayor nivel de actividad en niños que en niñas incluso al corregirlo por la masa corporal total. Conclusiones. Las diferencias entre los 3 criterios de diagnóstico de obesidad son patentes, de forma que nuestros datos globales de sobrepeso oscilarían entre el 29 y el 44,9% para los niños o entre el 20,3 y el 32,4% para las niñas, según el criterio utilizado (AU)

Objetivos: Apresentar as relações encontradas no primeiro ano do estudo longitudinal de 6 anos de duração entre a composição corporal, frequência de consumo de alimentos, nível de atividade física e prevalência de sobrepeso e obesidade em meninos e meninas de 6 anos. Método: O peso e a altura foram medidos mensalmente, calculando o índice de massa corporal (IMC) e passou-se um questionário de frequência de consumo de alimentos mediante o teste Kidmed de adesão a dieta mediterrânea e o questionário PAQ-C de atividade física. A partir dos dados de IMC obtiveram-se os valores correspondentes da ação de regressão de Cole e os percentis segundo as tabelas do CDC de Atlanta e da Fundação Orbegozo. Semestralmente foram realizadas biopedância monofrequência (BIA), cineantropometria completa e medição do gasto energético durante 2 dias consecutivos com um calorímetro ArmBand. Resultados: Os principais achados desse primeiro ano foram os seguintes: os dados obtidos por BIA e por cineantropometria mostram uma boa correlação, os dados do questionário Kimed não mostram correlação com os dados antropométricos nem com o IMC, os dados do PAQ-C e da calorimetria mostram um maior nível de atividade em meninos que em meninas, inclusive depois de corrigido pela massa corporal. Conclusões: As diferenças entre os 3 critérios de obesidade são notórias, de forma que nossos dados globais de sobrepeso oscilam entre 29 e 44,9% para meninos e entre 20,3 e 32,4% para as meninas, segundo o critério utilizado

Objectives. To present the results of a longitudinal study of six years with a group of children throughout the primary stage of education based on the relationships between body composition, frequency of food consumption, level of physical activity and the prevalence of overweight and obesity in 6 year-old children. Method. Monthly weight and height were measured, body mass index (BMI) was calculated and two questionnaires were administered: The Kidmed questionnaire of adherence to the Mediterranean diet for the frequency of food consumption, and the PAQ -C questionnaire for physical activity. Data corresponding to the regression equation of Cole and percentiles according to the tables of CDC Atlanta and the Foundation Orbegozo values were obtained from the BMI. Twice a year, a single frequency bioelectrical impedance (BIA) and a full kinanthropometry were assessed and measurement of energy expenditure was conducted over two consecutive days with an ArmBand calorimeter. Results. The main findings of this first year are as follows: Data obtained by BIA and kinanthropometry show a good correlation. The questionnaire data shows that KIDMED does not correlate with anthropometric data or BMI. Data from the PAQ- C and calorimetry show a higher level of activity in boys than in girls even when adjusted to the total body mass. Conclusions. The differences between the three diagnostic criteria of obesity are obvious, so that our global data overweight range between 29 and 44.9% for boys and between 20.3 and 32.4% for girls, depending on the criteria used (AU)

Daily patterns and adaptation of the ghrelin, growth hormone and insulin-like growth factor-1 system under daytime food synchronisation in rats.

Daytime restricted feeding promotes the re-alignment of the food entrained oscillator (FEO). Endocrine cues which secretion is regulated by the transition of fasting and feeding cycles converge in the FEO. The present study aimed to investigate the ghrelin, growth hormone (GH) and insulin-like growth factor (IGF)-1 system because their release depends on rhythmic and nutritional factors, and the output from the system influences feeding and biochemical status. In a daily sampling approach, rats that were fed ad lib. were compared with rats on a reversed (daytime) and restricted feeding schedule by 3 weeks (dRF; food access for 2 h), also assessing the effect of acute fasting and refeeding. We undertook measurements of clock protein BMAL1 and performed somatometry of peripheral organs and determined the concentration of total, acylated and unacylated ghrelin, GH and IGF-1 in both serum and in its main synthesising organs. During dRF, BMAL1 expression was synchronised to mealtime in hypophysis and liver; rats exhibited acute hyperphagia, stomach distension with a slow emptying, a phase shift in liver mass towards the dark period and decrease in mass perigonadal white adipose tissue. Total ghrelin secretion during the 24-h period increased in the dRF group as a result of elevation of the unacylated form. By contrast, GH and IGF-1 serum concentration fell, with a modification of GH daily pattern after mealtime. In the dRF group, ghrelin content in the stomach and pituitary GH content decreased, whereas hepatic IGF-1 remained equal. The daily patterns and synthesis of these hormones had a rheostatic adaptation. The endocrine adaptive response elicited suggests that it may be associated with the regulation of metabolic, behavioural and physiological processes during the paradigm of daytime restricted feeding and associated FEO activity.

Fallo multiorgánico en paciente con fungemia por Saprochaete capitata / Multi-organ failure in a patient with fungaemia due to Saprochaete capitata

Antecedentes. El aumento significativo de las infecciones fúngicas sistémicas es debido fundamentalmente al incremento de pacientes inmunodeprimidos. La morbimortalidad de estas infecciones es muy alta, lo que unido a los elevados costes de hospitalización que generan las convierten en una entidad de gran trascendencia en nuestra práctica hospitalaria. Saprochaete capitata es un hongo raro que causa infecciones invasivas habitualmente en pacientes inmunocomprometidos y para el que además no existe un consenso en la pauta terapéutica. Caso clínico. Presentamos un caso de infección diseminada por este hongo en una paciente intensamente inmunodeprimida, que fallece como consecuencia de un fallo multiorgánico a pesar de las medidas de soporte vital tomadas y del inicio de antibioterapia de amplio espectro. Conclusiones. Es de vital importancia iniciar el tratamiento antibiótico lo antes posible, así como la realización de cultivos de vigilancia y seguimiento para la búsqueda de hongos en los enfermos neutropénicos (AU)

[Multi-organ failure in a patient with fungaemia due to Saprochaete capitata]. / Fallo multiorgánico en paciente con fungemia por Saprochaete capitata.

BACKGROUND: The significant increase in systemic fungal infections is mainly due to the increase in immunocompromised patients. The high morbimortality of these infections, along with the high hospitalization costs they generate, makes them a problem of great importance in our hospital practice. Saprochaete capitata is a rare fungus that causes invasive infections, usually in immunocompromised patients, and for which there is still no consensus on the treatment regimen to be used. CASE REPORT: We present a case of disseminated infection by this fungus in a heavily immunosuppressed patient, who died as a result of multiple organ failure despite the life support measures taken and the wide spectrum antibiotics. CONCLUSIONS: It is vital to begin the antibiotic treatment as soon as possible, as well as the monitoring and follow-up cultures to test for fungi in neutropenic patients.

Cellular and intracellular distribution of growth hormone in the adult chicken testis.

Endocrine actions of growth hormone (GH) have been implicated during the development of adult testicular function in several mammalian species, and recently intracrine, autocrine, and paracrine effects have been proposed for locally expressed GH. Previous reports have shown the distribution of GH mRNA and the molecular heterogeneity of GH protein in both adult chicken testes and vas deferens. This study provides evidence of the presence and distribution of GH and its receptor (GHR) during all stages of spermatogenesis in adult chicken testes. This hormone and its receptor are not restricted to the cytoplasm; they are also found in the nuclei of spermatogonia, spermatocytes, and spermatids. The pattern of GH isoforms was characterized in the different, isolated germ cell subpopulations, and the major molecular variant in all subpopulations was 17 kDa GH, as reported in other chicken extra-pituitary tissues. Another molecular variant, the 29 kDa moiety, was found mainly in the enriched spermatocyte population, suggesting that it acts at specific developmental stages. The co-localization of GH with the proliferative cell nuclear antigen PCNA (a DNA replication marker present in spermatogonial cells) was demonstrated by immunohistochemistry. These results show for the first time that GH and GHR are present in the nuclei of adult chicken germinal cells, and suggest that GH could participate in proliferation and differentiation during the complex process of spermatogenesis.

Expression, cellular distribution, and heterogeneity of growth hormone in the chicken cerebellum during development.

Although growth hormone (GH) is mainly synthesized and secreted by pituitary somatotrophs, it is now well established that the GH gene can be expressed in many extrapituitary tissues, including the central nervous system (CNS). Here we studied the expression of GH in the chicken cerebellum. Cerebellar GH expression was analyzed by in situ hybridization and cDNA sequencing, as well as by immunohistochemistry and confocal microscopy. GH heterogeneity was studied by Western blotting. We demonstrated that the GH gene was expressed in the chicken cerebellum and that its nucleotide sequence is closely homologous to pituitary GH cDNA. Within the cerebellum, GH mRNA is mainly expressed in Purkinje cells and in cells of the granular layer. GH-immunoreactivity (IR) is also widespread in the cerebellum and is similarly most abundant in the Purkinje and granular cells as identified by specific neuronal markers and histochemical techniques. The GH concentration in the cerebellum is age-related and higher in adult birds than in embryos and juveniles. Cerebellar GH-IR, as determined by Western blot under reducing conditions, is associated with several size variants (of 15, 23, 26, 29, 35, 45, 50, 55, 80 kDa), of which the 15 kDa isoform predominates (>30% among all developmental stages). GH receptor (GHR) mRNA and protein are also present in the cerebellum and are similarly mainly present in Purkinje and granular cells. Together, these data suggest that GH and GHR are locally expressed within the cerebellum and that this hormone may act as a local autocrine/paracrine factor during development of this neural tissue.

Normalization of the heart rate response to exercise 6 months after cardiac transplantation.

INTRODUCTION: Heart transplant recipients show an abnormal heart rate (HR) response to exercise due to complete cardiac denervation after surgery. They present elevated resting HR, minimal increase in HR during exercise, with maximal HR reached during the recovery period. The objective of this study was to study the frequency of normalization of the abnormal HR in the first 6 months after transplantation. MATERIALS AND METHODS: We prospectively studied 27 heart transplant recipients who underwent treadmill exercise tests at 2 and 6 months after heart transplantation (HT). HR responses to exercise were classified as normal or abnormal, depending on achieving all of the following criteria: (1) increased HR for each minute of exercise, (2) highest HR at the peak exercise intensity, and (3) decreased HR for each minute of the recovery period. The HR response at 2 months was compared with the results at 6 months post-HT. RESULTS: At 2 months post-HT, 96.3% of the patients showed abnormal HR responses to exercise. Four months later, 11 patients (40.7%) had normalized HR responses (P<.001), which also involved a significant decrease in the time to achieve the highest HR after exercise (124.4±63.8 seconds in the first test and 55.6±44.6 seconds in the second). A significant improvement in exercise capacity and chronotropic competence was also shown in tests performed at 6 months after surgery. CONCLUSIONS: We observed important improvements in HR responses to exercise at 6 months after HT, which may represent early functional cardiac reinnervation.

New [2 × 2] copper(i) grids as anion receptors. Effect of ligand functionalization on the ability to host counteranions by hydrogen bonds.

Several complexes with a [2 × 2] grid structure have been obtained by the self-assembly of different copper(I) salts and ligands of the type 4,6-bis(pyrazol-1-yl)pyrimidine containing different substituents on the heterocycles. The main goal has been to evaluate the influence over the solid state and solution behavior of the functionalization of the pyrimidine ring with a primary amino substituent. The molecular and crystalline structures of some derivatives have been determined by X-ray diffraction. The grids contain two open voids formed by pairs of ligands facing one another on opposite sides of the grid in a somewhat divergent manner. One counteranion is hosted in each void interacting through hydrogen bonds and anion-π interactions. The presence of the amino group that points toward the inside of the cavity dominates the interactions in the void and apparently determines the orientation of the hosted counteranion and that of the ligands. With the exception of the derivative with chloride as the anion, the grid structure is preserved in solution (NMR and UV-vis) and some cation-anion interaction, increased by the presence of the amino group, exists also in solution (DOSY experiments). The experiments of anion interchange performed in solution indicate that a higher stability is found for the host-guest aggregates with OTs(-) (p-Me-C(6)H(4)SO(3)) and NO(3)(-). While for these anions a 1:2 stoichiometry is reached, for the rest of the anions tested (ReO(4)(-), OTf(-), and PF(6)(-)), only weaker 1:1 complexes are formed. Computational studies support the presence of anion-π interactions.

Growth hormone expression in stromal and non-stromal cells in the bursa of Fabricius during bursal development and involution: Causal relationships?

Growth hormone (GH) is expressed in the chicken bursa of Fabricius (BF), an organ that undergoes three distinct developmental stages: rapid growth (late embryogenesis until 6-8 weeks of age [w]), plateaued growth (between 10 and 15w), and involution (after 18-20w). The distribution and abundance of GH-immunoreactivity (GH-IR) and GH mRNA expression in stromal and non-stromal bursal cells during development, as well as the potential anti-apoptotic effect of GH in bursal cell survival were the focus of this study. GH mRNA expression was mainly in the epithelial layer and in epithelial buds at embryonic day (ED) 15; at 2w it was widely distributed within the follicle and in the interfollicular epithelium (IFE); at 10w it clearly diminished in the epithelium; whereas at 20w it occurred in only a few cortical cells and in the connective tissue. Parallel changes in the relative proportion of GH mRNA expression (12, 21, 13, 1%) and GH-IR (19, 18, 11, <3%) were observed at ED 15, 2w, 10w, and 20w, respectively. During embryogenesis, GH-IR co-localized considerably with IgM-IR, but scarcely with IgG-IR, whereas the opposite was observed after hatching. Significant differences in bursal cell death occurred during development, with 9.3% of cells being apoptotic at ED 15, 0.4% at 2w, 0.23% at 10w, and 21.1% at 20w. Addition of GH increased cultured cell survival by a mechanism that involved suppression (up to 41%) of caspase-3 activity. Results suggest that autocrine/paracrine actions of bursal GH are involved in the differentiation and proliferation of B lymphocytes and in BF growth and cell survival in embryonic and neonatal chicks, whereas diminished GH expression in adults may result in bursal involution.

First examples of a modulated bridging mu(2)-1:2kappan-triazine in double helical silver compounds. experimental and theoretical evidence.

The synthesis of several silver double helices containing bis(3,5dimethylpyrazolyl)-6-(R)-s-triazine ligands is described. The structure of two of them has been determined by X-ray difraction. Both derivatives represent the first reported examples of a new interaction mode for a triazine ring that involves a triazine N atom bridging two metal centers. Argentophilic contacts are also present. The Ag-N and Ag-Ag interactions have been demonstrated by theoretical studies, which also showed the clear influence of weak interactions with the counteranion and the effect of the symmetry of the triazine substituent. The different donor characters of these substituents allows a modulation of the strength of the bridging Ag-N(triazine) interaction. Double pi-pi stacking, anion-pi interactions, hydrogen bonds, and hydrophobic effects are observed in an unusual highly symmetrical interpenetrated three-dimensional superstructure.