Thyroid hormone concentrations associated with age, sex, reproductive status and apparent reproductive failure in the Amazon river dolphin (Inia geoffrensis).

This study was conducted to characterize immunoreactive thyroid hormone concentrations in wild Amazon river dolphins, also called boto (Inia geoffrensis) by age group, sex, pregnancy and lactation status, and to determine if thyroid hormone concentration differences could be detected between pregnant females with and without successful parturition outcomes. Radioimmunoassays were used to analyse total T 3 and total T 4 in 182 serum samples collected from 172 botos living in the Mamirauá Sustainable Development Reserve, in the Brazilian Amazon from 2003 through 2015. Age significantly affected tT 3 and tT 4 concentrations in males, with values in immature males and females being significantly lower than those in adult males, whereas no age effects were noted between immature females and adult non-pregnant, non-lactating females. Significant sex differences were noted in tT 3 concentrations between immature males and females and in tT 4 concentrations between adult males and females. These resulted in significant differences in the tT 3:tT 4 ratio between males and females within the immature and adult groups. Lactating and non-pregnant adult females had significantly higher tT 3 concentrations than pregnant females, and this difference was primarily driven by a 12% drop in tT 3 concentrations during the last two-thirds of pregnancy. No differences in thyroid hormone concentrations were detected between females diagnosed as pregnant and later found to have or not have a live calf. These results are the first to define thyroid hormone reference intervals and normal physiological variations in a wild population of river dolphins.

An autonomous medical monitoring system: Validation on arrhythmia detection.

In this paper, we present a generic platform for autonomous medical monitoring and diagnostics. We validated the platform in the context of arrhythmia detection with publicly available databases. The big advantage of this platform is its capacity to deal with various types of physiological signals. Many pre-processing steps are performed to bring the input information into a uniform state that will be explored by a machine learning algorithm. Since this block plays a crucial role in the entire processing pipeline, three different methods were evaluated for detection and classification of anomalies. The results presented in this work are validated on cardiac beats, where the highest accuracy was obtained on the classification of normal beats (94%). On the other hand, atrial fibrillation and premature ventricular contraction beats were classified with an accuracy of 78%.

The Complex Role of the ZNF224 Transcription Factor in Cancer.

ZNF224 is a member of the Kruppel-associated box zinc finger proteins (KRAB-ZFPs) family. It was originally identified as a transcriptional repressor involved in gene-specific silencing through the recruitment of the corepressor KAP1, chromatin-modifying activities, and the arginine methyltransferase PRMT5 on the promoter of its target genes. Recent findings indicate that ZNF224 can behave both as a tumor suppressor or an oncogene in different human cancers. The transcriptional regulatory properties of ZNF224 in these systems appear to be complex and influenced by specific sets of interactors. ZNF224 can also act as a transcription cofactor for other DNA-binding proteins. A role for ZNF224 in transcriptional activation has also emerged. Here, we review the state of the literature supporting both roles of ZNF224 in cancer. We also examine the functional activity of ZNF224 as a transcription factor and the influence of protein partners on its dual behavior. Increasing information on the mechanism through which ZNF224 can operate could lead to the identification of agents capable of modulating ZNF224 function, thus potentially paving the way to new therapeutic strategies for treatment of cancer.

Amphiphilic block copolymers as flexible membrane materials generating structural and functional mimics of green bacterial antenna complexes.

We describe the ability of a short-chain amphiphilic block copolymer to self-assemble to form an artificial supramolecular light-harvesting system. Specifically, we demonstrate that the 2.5 kDa, poly(ethylene oxide)-block-poly(butadiene) (PEO-b-PBD), exhibits sufficient morphological flexibility as a membrane material and enables generation of mimics of three-dimensional chlorosomes as well as supported membrane bilayers containing energy acceptors. This overall architecture replicates green bacterial light-harvesting function whereby these assemblies exhibit long-range order and three-dimensional morphology similar to native chlorosomes and are capable of energy transfer internally and to external acceptors, located in a supporting biomimetic polymer membrane. Unlike native green bacterial systems that use multiple lipids as a matrix to generate the appropriate environment for chlorosome assembly and function, the described system matrix is comprised entirely of a single polymer amphiphile. This work demonstrates the potential of short-chain amphiphilic block copolymers in generating self-assembled, bio-mimetic membrane architectures, and in doing so, generates scalable, spatial-energetic landscapes for photonic applications. Finally, the results presented provide evidence of minimal requirements to induce chlorosome-like organization and function.

Validación psicométrica de escalas PSS-14, AFA-R, HDRS, CES-D, EV en puérperas mexicanas con y sin preeclampsia / Psychometric validation of scales PSS-14, AFA-R, HDRS, CES-D, EV in postpartum Mexican women with and without preeclampsia / Validação das escalas PSS, AFA-R, HDRS, CES-D e EV em puérperas mexicanas com e sem pré-eclâmpsia

Objetivo: Validar las escalas psicométricas: Estrés percibido (PSS), Apoyo familiar y de amigos (AFA-R), Depresión de Hamilton (HDRS), Sintomatología depresiva (CES-D), Violencia e índice de severidad (EV) en mujeres mexicanas puérperas con y sin preeclamsia. Método: Estudio descriptivo que valida las propiedades psicométricas de las escalas PSS, AFA-R, HDRS, CES-D y EV. Las escalas fueron seleccionadas a través de una búsqueda en la web de los últimos 5 años. Las escalas fueron aplicadas por enfermeras mediante entrevista a 104 puérperas hospitalizadas con y sin preeclampsia. Para la confiabilidad se aplicó el alfa de Cronbach. La validez fue confirmada por un grupo de expertos y prueba piloto. Se utilizó análisis factorial por los métodos componentes principales, Káiser y Varimax. Resultados: Cada escala tuvo consistencia interna; calificaron con nivel aceptable (PSS 0.718 y EV 0.740) y nivel bueno (AFA-R 0.911, CES-D 0.869 y HDRS 0.806). La validez de contenido fue aprobada con: PSS 96.42%; EV 100%; AFA 100%; CES-D 98.75%, y HDRS 92.64%. La estructura factorial estuvo bien distribuida: cada factor obtuvo algunos pesos altos y los demás, próximos a cero. Cada variable estuvo saturada en uno o en 2 factores, por lo que casi no compartieron varianzas. PSS, con 6 factores, tuvo poder explicativo de la varianza total del 72.23%; AFA-R, con 3 factores y poder explicativo del 74.19%; HDRS, con 6 factores y poder explicativo del 70.58%; CES-D, con 6 factores y poder explicativo del 72.87%, y la escala EV tuvo varianza de cero. Conclusiones: Los hallazgos señalan que las escalas PSS, AFA-R, HDRS y CES-D por su confiabilidad, validez y utilidad funcionan teóricamente bien para medir las variables en el grupo de mujeres estudiadas; sin embargo para la escala EV debe considerarse un análisis factorial diferente en otra muestra similar.

Objective: To assess the following scales' psychometric characteristics: Perceived Stress (PSS), Family and Friends Support (AFA-R), Depression-Hamilton (HDRS), Depressive Symptomatology (CES-D), Violence and Index of Severity (EV) among Mexican populations, with and without pre-eclampsia. Method: Descriptive and psychometric study. A web search was conducted to decide on which scales use. Nurses applied the scales to 104 hospitalized post-partum women with and without pre-eclampsia. Cronbach alpha was measured to assess reliability. Validity was confirmed by a group of experts and by a pilot study. Principal components, Kaiser, and varimax factor analyses were carried out.ResultsEach scale had internal consistency-acceptable level: PSS .718 and EV .740; good level: AFA-R .911, CES-D .869 and HDRS .806. Content validity was assessed as PSS: 96.42%, EV: 100%, AFA 100%, CES-D: 98.75% and HDRS: 92.64%. The factor structure was well distributed. Each factor had few important weights, and the rest were close to zero. Each variable was not saturated except in one, and barely in two, factors, thus variance was almost not shared. PSS, with 6 factors, had an explicative power of the total variance of 72.23%; AFA-R, with 3 factors and explicative power of 74.19%; HDRS with 6 factors and explicative power of 70.58%; while CES-D, with 6 factors too, had an explicative power of 72.87%. The EV scale had a variance of zero. Conclusions: Findings suggest that the scales PSS, AFA-R, HDRS, and CES-D, due to their reliability, validity, and usefulness, theoretically work well to assess the different variables among the group of studied women. Another factor analysis on the EV scale should be considered for a similar sample.

Objetivo: Validar as escalas psicométricas: Estrese Percebido (PSS), Apoio Familiar e de Amigos (AFA-R), Depressão de Hamilton (HDRS), Sintomatologia Depressiva (CES-D), Violência e Índice DE Severidade (EV) em mulheres mexicanas puérperas com e sem pré-eclâmpsia. Método: Estudo descritivo que valida as propriedades psicométricas das escalas PSS, AFA-R, HDRS, CES-D e EV. As escalas foram escolhidas a través de uma busca na web dos últimos 5 anos. As escalas foram aplicadas por enfermeiras mediante entrevista a 104 puérperas hospitalizadas com e sem pré-eclâmpsia. Para a confiabilidade aplicou-se alfa de Crombach. A validade foi confirmada por um grupo de experientes e prova piloto. Utilizou-se analise fatorial pelos métodos componentes principais, Káiser e Varimax. Resultados: Cada escala teve consistência interna; qualificaram com nível aceitável (PSS 0.718 y EV 0.740) e com nível bom (AFA-R 0.911, CES-D 0.869 y HDRS 0.806). A validade de conteúdo foi aprovada com: PSS 96.42%; EV 100%; AFA 100%; CES-D 98.75%, e HDRS 92.64%. A estrutura fatorial esteve bem distribuída, cada fator obteve alguns pesos altos e os outros próximos a zero. Cada variável esteve saturada em um ou em outros fatores, pelo que quase não compartilharam variâncias. PSS, com 6 fatores, teve poder explicativo da variância total do 72.23%; AFA-R, com 3 fatores e poder explicativo do 74.19%; HDRS, com 6 fatores e poder explicativo do 70.58%; CES-D, com 6 fatores e poder explicativo do 72.87%, e a escala EV teve variância de zero. Conclusões: As descobertas assinalam que as escalas PSS, AFA-R, HDRS e CES-D por sua confiabilidade, validade e utilidade funcionam teoricamente bem para medir as variáveis no grupo de mulheres estudadas; porém, para a escala EV deve se considerar uma análise fatorial diferente em outra amostra semelhante.

Sperm sex-sorting and preservation for managing the sex ratio and genetic diversity of the southern white rhinoceros (Ceratotherium simum simum).

White rhinoceros ejaculates (n=9) collected by electroejaculation from four males were shipped (10°C, 12h) to develop procedures for the production of chilled and frozen-thawed sex-sorted spermatozoa of adequate quality for artificial insemination (AI). Of all electroejaculate fractions, 39.7% (31/78) exhibited high quality post-collection (≥70% total motility and membrane integrity) and of those, 54.8% (17/31) presented reduced in vitro quality after transport and were retrospectively determined to exhibit urine-contamination (≥21.0µg creatinine/ml). Of fractions analyzed for creatinine concentration, 69% (44/64) were classified as urine-contaminated. For high quality non-contaminated fractions, in vitro parameters (motility, velocity, membrane, acrosome and DNA integrity) of chilled non-sorted and sorted spermatozoa were well-maintained at 5°C up to 54h post-collection, whereby >70% of post-transport (non-sorted) or post-sort (sorted) values were retained. By 54h post-collection, some motility parameters were higher (P<0.05) for non-sorted spermatozoa (total motility, rapid velocity, average path velocity) whereas all remaining motion parameters as well as membrane, acrosome and DNA integrity were similar between sperm types. In comparison with a straw method, directional freezing resulted in enhanced (P<0.05) motility and velocity of non-sorted and sorted spermatozoa, with comparable overall post-thaw quality between sperm types. High purity enrichment of X-bearing (89±6%) or Y-bearing (86±3%) spermatozoa was achieved using moderate sorting rates (2540±498X-spermatozoa/s; 1800±557Y-spermatozoa/s). Collective in vitro characteristics of sorted-chilled or sorted-frozen-thawed spermatozoa derived from high quality electroejaculates indicate acceptable fertility potential for use in AI.

Taller de herramientas teórico-metodológicas con perspectiva de género para el ejercicio libre de la profesión de Enfermería. Un estudio exploratorio / Gender perspective theory and methodology tools workshop for the free practice of the Nursing profession. An exploratory study

Objetivo: Presentar un estudio exploratorio que analiza las actitudes que los profesionales de la Enfermería tienen en relación al ejercicio libre de su disciplina, para instalar y trabajar en un consultorio privado. Métodos: Se realizó un taller sobre herramientas teórico-metodológicas con perspectiva de género para el ejercicio libre de la Enfermería, se aplicó un cuestionario pretest y postest a la realización del taller, participaron 3 grupos de trabajo con sedes en Facultad de Estudios Superiores Iztacala (FES-I), Facultad de Estudios Superiores Zaragoza (FES-Z) y Escuela Nacional de Enfermería y Obstetricia (ENEO) de la Universidad Nacional Autónoma de México (UNAM). El eje de análisis de los resultados se realizó desde el enfoque de género de forma inter e intragrupal. Resultados: Se encontró que la formación curricular de la profesión influye en el no ejercicio libre de la carrera, tendiendo a centralizar su función en instituciones de salud, así como a limitar el conocimiento y aplicación de su profesión basado principalmente en estereotipos sexuales, de feminización y sexismo de las profesiones. Conclusiones: La importancia del empoderamiento como herramienta metodológica de la perspectiva de género aportará en los profesionales de la Enfermería, las habilidades necesarias para el ejercicio libre de la profesión a través del desarrollo de capacidades de crecimiento personal.

Objective: The objective of this study is to analyze the attitudes of the nursing professionals in relation to their discipline's free practice to establish and work in a private consulting office. Methods: A workshop on theory and methodology tools under the gender perspective was conducted. Pretest and posttests questionnaires were given to 3 work groups at Facultad de Estudios Superiores Iztacala (FES-I), Facultad de Estudios Superiores Zaragoza (FES-Z) y Escuela Nacional de Enfermería y Obstetricia (ENEO) of the Universidad Nacional Autónoma de México (UNAM). The analysis was performed on both inter and intra groups. Results: It was found that the career curriculum influences on the free practice of the profession tending to centralize its functions to health institutions, and that, under feminization and sexist arguments, its knowledge and applications are limited. Conclusions: The importance of empowerment as a gender perspective methodology tool will provide nursing professionals with the necessary skills for their free practice through their personal development.

Development and evaluation of deep intra-uterine artificial insemination using cryopreserved sexed spermatozoa in bottlenose dolphins (Tursiops truncatus).

Since its development in bottlenose dolphins, widespread application of AI with sex-selected, frozen-thawed (FT) spermatozoa has been limited by the significant expense of the sorting process. Reducing the total number of progressively motile sperm (PMS) required for an AI would reduce the sorting cost. As such, this research compared the efficacy of small-dose deep uterine AI with sexed FT spermatozoa (SEXED-SMALL; ~50×10(6)PMS, n=20), to a moderate dose deposited mid-horn (SEXED-STD, ~200×10(6)PMS; n=20), and a large dose of FT non-sexed spermatozoa deposited in the uterine body (NONSEXED-LARGE, 660×10(6)PMS, n=9). Ten of the 11 calves resulting from use of sexed spermatozoa were of the predetermined sex. Similar rates of conception (NONSEXED-LARGE: 78%, SEXED-STD: 60%, SEXED-SMALL: 57%) and total pregnancy loss (TPL: NONSEXED-LARGE: 28.6%; SEXED-STD: 41.0%; SEXED-SMALL: 63.6%) were observed across groups, but early pregnancy loss (EPL,

Sperm DNA fragmentation and morphological degeneration in chilled elephant (Elephas maximus and Loxodonta Africana) semen collected by transrectal massage.

Ejaculates from nine Asian and two African elephants were analysed to gain a further understanding of mechanisms underlying variable semen quality after transrectal massage. Semen analysis was performed after collection (0 h; subjective motility parameters only) and after 24 h of chilled storage at 10 °C (24 h; all ejaculate and sperm characteristics). Ejaculates with ≤50% total motility (TM) at 24 h, which represented >90% of collection attempts, contained a sperm population with a high degree of DNA damage (64.2 ± 19.2% fragmented DNA) and an elevated incidence of detached heads (43.3 ± 22.5%). In contrast, good quality ejaculates designated as those with >50% TM at 24 h displayed higher (p < 0.05) values of sperm kinetic parameters, DNA integrity and normal morphology. Fertility potential was high for good quality ejaculates from two males (one Asian and one African bull) based on in vitro characteristics after chilled storage for up to 48 h post-collection. Urine contamination of semen, as assessed quantitatively by creatinine concentration, was confirmed as a significant factor in reduced elephant ejaculate quality. However, the identification of considerable DNA damage and morphological degeneration in the majority of ejaculates after only 24 h of chilled storage indicates that sperm ageing could be a primary contributor to inconsistent semen quality in the elephant.

Characteristics of high-quality Asian elephant (Elephas maximus) ejaculates and in vitro sperm quality after prolonged chilled storage and directional freezing.

The in vitro quality of spermatozoa from one elephant (Elephas maximus) was examined after chilled storage and directional freezing (DF). High-quality, non-contaminated ejaculates (77.6±6.0% progressive motility, 3.9±1.5 µg creatinine mL(-1) raw semen, 2.7±0.6% detached heads) were cryopreserved after 0 (0hStor), 12 (12hStor) and 24 h (24hStor) of chilled storage. At 0 h and 6h post-thawing, total motility, plasma membrane integrity, acrosome integrity, mitochondrial activity and normal morphology were similar (P>0.05) across treatments. In contrast, progressive motility, rapid velocity and several kinematic parameters were lower (P<0.05) for 24Stor compared with 0hStor at 0 h post-thaw. By 6 h post-thaw, amplitude of lateral head displacement and velocity parameters (average pathway, straight-line and curvilinear velocity) were lower (P<0.05) for 24hStor compared with 0hStor and 12hStor. DNA integrity was high and remained unchanged (P>0.05) across all groups and processing stages (1.6±0.6% of cells contained fragmented DNA). Results indicate that DF after up to 12 h of chilled storage results in a post-thaw sperm population of acceptable quality for artificial insemination. These findings have implications for the cryopreservation of sex-sorted spermatozoa, which typically undergo more than 12 h of chilled storage prior to sorting and preservation.

Evaluation of motility, membrane status and DNA integrity of frozen-thawed bottlenose dolphin (Tursiops truncatus) spermatozoa after sex-sorting and recryopreservation.

Artificial insemination (AI) with sex-sorted frozen-thawed spermatozoa has led to enhanced management of ex situ bottlenose dolphin populations. Extended distance of animals from the sorting facility can be overcome by the use of frozen-thawed, sorted and recryopreserved spermatozoa. Although one bottlenose dolphin calf had been born using sexed frozen-thawed spermatozoa derived from frozen semen, a critical evaluation of in vitro sperm quality is needed to justify the routine use of such samples in AI programs. Sperm motility parameters and plasma membrane integrity were influenced by stage of the sex-sorting process, sperm type (non-sorted and sorted) and freezing method (straw and directional) (P<0.05). After recryopreservation, sorted spermatozoa frozen with the directional freezing method maintained higher (P<0.05) motility parameters over a 24-h incubation period compared to spermatozoa frozen using straws. Quality of sperm DNA of non-sorted spermatozoa, as assessed by the sperm chromatin structure assay (SCSA), was high and remained unchanged throughout freeze-thawing and incubation processes. Though a possible interaction between Hoechst 33342 and the SCSA-derived acridine orange was observed in stained and sorted samples, the proportion of sex-sorted, recryopreserved spermatozoa exhibiting denatured DNA was low (6.6±4.1%) at 6 h after the second thawing step and remained unchanged (P>0.05) at 24 h. The viability of sorted spermatozoa was higher (P<0.05) than that of non-sorted spermatozoa across all time points after recryopreservation. Collective results indicate that bottlenose dolphin spermatozoa undergoing cryopreservation, sorting and recryopreservation are of adequate quality for use in AI.

Deep intra-uterine artificial inseminations using cryopreserved spermatozoa in beluga (Delphinapterus leucas).

Artificial insemination (AI) with liquid-stored spermatozoa and sperm cryopreservation using directional freezing (DF) have been successful in the beluga. This study built on this foundation to develop a deep intra-uterine AI technique with frozen-thawed semen in beluga. Forty-two ejaculates from one male were cryopreserved using DF technology and subsequently used for 10 insemination attempts with seven females. Percentage pre- and post-thaw progressive motility and viability were (mean +/- SD) 73.0 +/- 12.2, 38.4 +/- 8.8, 88.0 +/- 0.1, and 59.3 +/- 15.7%, respectively. A series of GnRH injections (3 x 250 microg, IV, 1.5 to 2 h apart) were used to induce ovulation, once a growing follicle >2.5 cm in diameter was visualized via trans-abdominal ultrasonography. Artificial insemination was performed at 30.1 +/- 3.8 h post-initial GnRH injection with semen deposited in the uterine horn, 92.6 +/- 16.2 cm beyond the genital opening using a flexible endoscope. The external cervical os (cEOS) was located beyond a series of 5 to 10 vaginal rings, 44.8 +/- 9.3 cm from the external genital opening. The internal bifurcation of the uterus was 27 +/- 6.8 cm beyond the cEOS. Ovulation occurred at 8.5 +/- 7.6 h post-AI. Two of 10 inseminations (20%) resulted in pregnancy. The first pregnancy resulted in twins; both calves were born 442 d after AI, with one surviving. The second pregnancy is ongoing. These findings represent the first successful application of AI using frozen-thawed semen in beluga, and are important examples of how assisted reproductive technologies can provide tools for the global management of threatened species.

Factores de riesgo para enfermedades crónicas en universitarias del área de la salud / Chronic illnesses risk factors in university personnel from the health areas

El propósito del estudio fue identificar la presencia de factores de riesgo para enfermedades crónicas no transmisibles (ECNT) en un grupo de 37 universitarias de la Facultad de Estudios Superiores Iztacala de la UNAM, con el fin de diseñar una estrategia de intervención. Material y métodos: Es un estudio, cuantitativo, descriptivo y transversal. Resultados: Se encontró que los factores de riesgo más comunes en esta población fueron los antecedentes hereditarios de diabetes, hipertensión arterial y cáncer. Entre los factores personales que destacaron, se encuentra la inactividad física deportiva, el sobrepeso, obesidad, sedentarismo y la jornada laboral prolongada. En los Papanicolaou realizados se encontró proceso infeccioso. Discusión: El factor obesidad tuvo mayor prevalencia en los grupos de académicas y administrativas. Las académicas duermen menos horas, por dedicar más tiempo al trabajo remunerado. Se encontraron tabúes relacionados con la región genital, que limitan la realización de exámenes preventivos. Conclusiones: Se observó, alta prevalencia de factores de riesgo para desarrollar ECNT. Se propuso un plan de intervención para promover estilos de vida saludables, considerar a la facultad como campo de práctica comunitaria, donde se lleve a cabo el fomento para la salud y la protección específica de enfermedades, a través acciones formativas que promuevan el consumo de dietas personalizadas, educación sexual, prevención de adicciones, seguimiento de casos y el uso de las instalaciones deportivas, favoreciendo así la salud integral de las universitarias

Management of periocular basal cell carcinoma: Mohs' micrographic surgery versus radiotherapy.

In treating periocular basal cell carcinoma the goal is to achieve the most complete eradication of affected tissue while preserving as much healthy tissue as possible. In the first of these "Viewpoints" articles, Drs. Leshin and Yeatts discuss the success of Mohs' microsurgical technique (MMS) in both regards. Moreover, they note that MMS offers the additional advantage of placing all surgical and histological phases of tumor excision in the hands of one specialist, thus circumventing problems that may arise with procedures requiring the separate involvement of several specialists. In the second article, Drs. Anscher and Montana point out that modern radiotherapy techniques may offer adequate tumor control with less damage to surrounding tissues than is caused by surgical excision and reconstruction. With small lesions, radiotherapy has a success rate similar to that of surgery. With large lesions, the success rate is lower; however, if surgical excision would cause extensive disfigurement or functional damage, an initial trial of radiotherapy may be warranted, then followed by surgery, if necessary. In an editorial, Dr. Dutton summarizes the indications for and advantages and disadvantages of both techniques.

Estudio de crecidas en la cuenca del Rio Yacuma

La llanura beniana se encuentra periodicamente sometida a grandes inundacioenes que afectan en forma general las actividades de la zona y en forma especial la ectividad ganadera, y también con perjuicios económicos. El presente trabajo pretendión en principio realizar un estudio detallado del problema, y, mediante su aplicación a una hacienda (Espíritu) situada en la cuenca del Rio Yacuma, proponer soluciones concretas que podrián emplearse en toda la zona. Por este motivo el estudio se limita al cálculo e investigación de las crecidas que afectan la cuenca del Río Yacuma, mediante el empleo de métodos teóricos (especialmente el método de CLARK), que en caso del estudio no se pueden verificar por no disponer de registros hidrométricos, pudiendo en consecuencia arribarse a conclusiones alejadas de la realidad.

[The malignant struma. Pathological anatomy and functional criteria]. / Die maligne Struma. Pathologische Anatomie und funktionelle Eigenschaften

Description of the pathological anatomy of thyroid cancer with classification into carcinomas, sarcomas and special forms of tumors. Concerning the carcinomas of the thyroid gland, the malignant papilloma (papillary carcinoma) and the medullary amyloid- and calcitonin-producing carcinoma deserve special consideration because of their small malignancy and therefore favourable prognosis. Also the proliferating struma Langhans does not come up to "real" carcinomas (organoid structure of the tumor tissue) concerning the growing speed. All other types of carcinomas, as well as sarcomas, are fast growing malignant tumors, which also place metastases early. The metastasizing struma-adenoma is not a malignant tumor in the sense of the term. In addition, it is necessary to refer to the existing difficulties in marking off clearly structurally sarcomatous tumors of the thyroid gland from carcinomas. Besides, one must emphasize, that thyreostatic substances, also ionizing rays (i.e. radioiodine) can produce considerable tissue-changes with cell polymorphia and that a considerable increase in the number of large-cell eosinophilic adenomas (oncocytomas, Hürthle-cell adenomas) exists. The sclerosizing microcarcinoma (Graham's tumor) is not a carcinoma in the sense of the term.