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1.
Conserv Biol ; 35(5): 1586-1597, 2021 10.
Article in English | MEDLINE | ID: mdl-33877716

ABSTRACT

Assessing the scope and severity of threats is necessary for evaluating impacts on populations to inform conservation planning. Quantitative threat assessment often requires monitoring programs that provide reliable data over relevant spatial and temporal scales, yet such programs can be difficult to justify until there is an apparent stressor. Leveraging efforts of wildlife management agencies to record winter counts of hibernating bats, we collated data for 5 species from over 200 sites across 27 U.S. states and 2 Canadian provinces from 1995 to 2018 to determine the impact of white-nose syndrome (WNS), a deadly disease of hibernating bats. We estimated declines of winter counts of bat colonies at sites where the invasive fungus that causes WNS (Pseudogymnoascus destructans) had been detected to assess the threat impact of WNS. Three species undergoing species status assessment by the U.S. Fish and Wildlife Service (Myotis septentrionalis, Myotis lucifugus, and Perimyotis subflavus) declined by more than 90%, which warrants classifying the severity of the WNS threat as extreme based on criteria used by NatureServe. The scope of the WNS threat as defined by NatureServe criteria was large (36% of Myotis lucifugus range) to pervasive (79% of Myotis septentrionalis range) for these species. Declines for 2 other species (Myotis sodalis and Eptesicus fuscus) were less severe but still qualified as moderate to serious based on NatureServe criteria. Data-sharing across jurisdictions provided a comprehensive evaluation of scope and severity of the threat of WNS and indicated regional differences that can inform response efforts at international, national, and state or provincial jurisdictions. We assessed the threat impact of an emerging infectious disease by uniting monitoring efforts across jurisdictional boundaries and demonstrated the importance of coordinated monitoring programs, such as the North American Bat Monitoring Program (NABat), for data-driven conservation assessments and planning.


Alcance y Severidad del Síndrome de Nariz Blanca en los Murciélagos Hibernando en América del Norte Resumen La evaluación del alcance y la severidad de las amenazas es necesaria para los análisis de impacto sobre las poblaciones que se usan para orientar a la planeación de la conservación. La evaluación cuantitativa de amenazas con frecuencia requiere de programas de monitoreo que proporcionen datos confiables en escalas espaciales y temporales, aunque dichos programas pueden ser difíciles de justificar hasta que exista un estresante aparente. Gracias a una movilización de esfuerzos de las agencias de manejo de fauna para registrar los conteos invernales de murciélagos hibernadores, recopilamos datos para cinco especies en más de 200 sitios a lo largos de 27 estados de EUA y dos provincias canadienses entre 1995 y 2018 para determinar el impacto del síndrome de nariz blanca (SNB), una enfermedad mortal de los murciélagos hibernadores. Estimamos declinaciones en los conteos invernales de las colonias de murciélagos en sitios en donde el hongo invasivo que ocasiona el SNB (Pseudogymnoascus destructans) había sido detectado para evaluar el impacto de amenaza del SNB. Tres especies que se encuentran bajo valoración por parte del Servicio de Pesca y Vida Silvestre de los EUA (Myotis septentrionalis, Myotis lucifugus y Perimyotis subflavus) tuvieron una declinación de más del 90%, lo que justifica la clasificación de la severidad de la amenaza del SNB como extrema con base en el criterio usado por NatureServe. El alcance de la amenaza del SNB definido por el criterio de NatureServe fue desde amplio (36% de la distribución de Myotis lucifugus) hasta dominante (79% de la distribución de Myotis septentrionalis) para estas especies. Las declinaciones de otras dos especies (Myotis sodalis y Eptesicus fuscus) fueron menos severas, pero de igual manera quedaron clasificadas desde moderada hasta seria con base en los criterios de NatureServe. El intercambio de datos entre las jurisdicciones proporcionó una evaluación completa del alcance y la severidad de la amenaza del SNB e indicó las diferencias regionales que pueden guiar a los esfuerzos de respuesta realizados en las jurisdicciones internacionales, nacionales, estatales o provinciales. Evaluamos el impacto de amenaza de una enfermedad infecciosa emergente mediante la combinación de los esfuerzos de monitoreo que sobrepasan fronteras jurisdiccionales y demostramos la importancia que tienen para la planeación y la evaluación basadas en datos de la conservación los programas de monitoreo coordinados, como el Programa de Monitoreo de los Murciélagos Norteamericanos (NABat).


Subject(s)
Chiroptera , Hibernation , Animals , Ascomycota , Canada , Conservation of Natural Resources , North America
2.
J Wildl Dis ; 50(3): 694-5, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24807361

ABSTRACT

On 16 March 2012 a rabid eastern red bat (Lasiurus borealis) was found attached to an evening bat (Nycticeius humeralis) in Randolph County, Arkansas, USA. This appears to be the first confirmed case of a rabid bat attacking a bat of another species.


Subject(s)
Aggression , Chiroptera , Rabies/veterinary , Animals , Female , Rabies/complications , Rabies/epidemiology , Rabies/pathology , Rabies virus/isolation & purification
3.
Histochem Cell Biol ; 116(6): 465-9, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11810188

ABSTRACT

By means of a microelectrophoretic separation technique the different forms of alcohol dehydrogenase can be detected in microdissected liver tissue samples of the nanogram range. Alcohol dehydrogenase 3 (the glutathione-dependent formaldehyde dehydrogenase) was demonstrated to be zonally distributed in the human liver parenchyma. A periportal/perivenous gradient is evident in both sexes, however, the periportal/perivenous ratio is higher in males. The biological functions of this enzymatic form and the possible role of the periportal maximum are discussed.


Subject(s)
Aldehyde Oxidoreductases/metabolism , Liver/enzymology , Female , Humans , Isoelectric Focusing , Male , Nanotechnology , Organ Size , Sex Characteristics
4.
Histochem J ; 32(8): 515-20, 2000 Aug.
Article in English | MEDLINE | ID: mdl-11095078

ABSTRACT

In rodents, the vaginal epithelium undergoes cyclical changes with an alternating pattern of keratinization and mucification. It has been known for decades that vitamin A and its active form retinoic acid are responsible for normal epithelial homeostasis. However, it has not so far been certain which enzymes catalyze the first and rate-limiting step in retinoic acid synthesis. By means of microdissection and ultrathin-layer gel electrophoresis, alcohol dehydrogenase isoenzyme activity was determined quantitatively in the various layers of the vaginal mucous membrane. It was found that, in the rat, only alcohol dehydrogenase 3 and 4 are expressed. Marked cyclical changes of alcohol dehydrogenase 4 activity in the stratum germinativum of the vaginal epithelium strongly support the assumption that this isoenzyme is responsible for retinoic acid synthesis, and that it is essential for the changes accompanying keratinization and mucification.


Subject(s)
Alcohol Dehydrogenase/metabolism , Estrus , Vagina/enzymology , Animals , Female , Histocytochemistry , Isoenzymes/metabolism , Rats , Rats, Wistar
5.
J Am Coll Health ; 48(6): 297-304, 2000 May.
Article in English | MEDLINE | ID: mdl-10863873

ABSTRACT

Much of the existing research on disordered eating has centered on the drive for thinness, which is most commonly observed in girls and women. The male standard of bodily attractiveness, however, is bigger, bulkier, and more muscular. Are boys and men motivated to be big and muscular in the same way that girls and women are motivated to be thin? The authors constructed a 15-item survey and administered it to 197 adolescents. The findings showed that the drive for muscularity measure displayed good reliability; that individuals high in the drive were more likely to be boys who were trying to gain both weight and muscle mass; that the drive was related to poor self-esteem and higher levels of depression among boys, but not among girls; and that the drive for muscularity was relatively unrelated to the drive for thinness.


Subject(s)
Adolescent Behavior , Body Image , Muscle, Skeletal/physiology , Self Concept , Adolescent , Adult , Canada , Drive , Female , Humans , Male , Sensitivity and Specificity , Sex Factors , Surveys and Questionnaires , Weight Lifting
6.
Histochem Cell Biol ; 111(6): 461-6, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10429968

ABSTRACT

To elucidate the pattern of lesions in the liver parenchyma after ethanol ingestion, the quantitative distribution profiles of both the cytosolic and the mitochondrial aldehyde dehydrogenase isoenzyme activities were determined by the use of ultrathin-layer electrophoresis. It was found that in human liver parenchyma, both isoforms of aldehyde dehydrogenase are almost homogeneously represented in the liver acinus. These quantitative data are supported by the results of an improved histochemical technique. Moreover, sex differences were not detected either in activity or in the distribution pattern. Consequently, it can be assumed that it is not the activity of total aldehyde dehydrogenase or its isoforms which is responsible for the higher susceptibility of the perivenous zone to alcohol-dependent damage.


Subject(s)
Aldehyde Dehydrogenase/metabolism , Isoenzymes/metabolism , Liver/enzymology , Aldehyde Dehydrogenase 1 Family , Aldehyde Dehydrogenase, Mitochondrial , Electrophoresis, Polyacrylamide Gel , Female , Humans , Male , Myocardium/enzymology , Organ Size , Retinal Dehydrogenase
7.
Histochem Cell Biol ; 111(5): 391-7, 1999 May.
Article in English | MEDLINE | ID: mdl-10403118

ABSTRACT

By the use of a newly developed technique of ultrathin-layer electrophoresis, class I and class II alcohol dehydrogenase activity could be demonstrated in microdissected samples of the periportal, intermediate, and perivenous zones of the liver acinus in men and women. It could be demonstrated that both classes exhibit low activity in the periportal zone. From there, a rising gradient in the direction of the perivenous end was apparent. This increase, however, was found to be significant only in women. The analysis of class I alcohol dehydrogenase isoenzymes showed that the expression of alpha-, beta-, and gamma-containing isoforms did not differ in relation to the intraacinar position. The constant proportions of the isoenzymes to the maxima and minima of the total alcohol dehydrogenase activity support the view that the adult liver-specific isoenzyme pattern is determined during postnatal development.


Subject(s)
Alcohol Dehydrogenase/metabolism , Liver/enzymology , Adult , Electrophoresis, Polyacrylamide Gel , Female , Humans , Isoenzymes/metabolism , Male , Organ Size
8.
Ann Anat ; 181(2): 223-7, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10332527

ABSTRACT

The transplantation of a donor kidney is currently the treatment of choice for terminal renal insufficiency. However, major postoperative problems may be caused by vascular complications. It was therefore decided to look for possible correlations between these vascular problems and the arterial wall supply. The following methods were used to elucidate the origin and distribution of nutrient vessels: 1. Injection of the abdominal aorta with resin in three fresh cadavers. 2. The precise microscopic location of the branches originating from the renal arteries in eighteen autopsy subjects. 3. Abdominal angiography and selective angiography of the first left lumbar artery and left renal artery in one patient. It was found that the renal artery receives its blood supply from both internal and external nutrient vessels. The external vascular supply of the renal arterial wall originates from the aorta itself, from the inferior suprarenal artery (which sometimes has connections with the first and/or second lumbar artery) or from the diffuse vascular system of the retroperitoneal space. Because of the variety in number, course and origin of these nutritional vessels, an ideal point for the anastomosis of the renal artery cannot be indicated.


Subject(s)
Aorta, Abdominal/anatomy & histology , Renal Artery/anatomy & histology , Vasa Vasorum/anatomy & histology , Aged , Aged, 80 and over , Angiography , Autopsy , Female , Humans , Male , Middle Aged , Renal Artery/diagnostic imaging , Resins, Plant , Sex Characteristics , Vasa Vasorum/diagnostic imaging
9.
Electrophoresis ; 19(10): 1654-8, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9719541

ABSTRACT

A highly sensitive electrophoretic technique for the separation of alcohol dehydrogenase isoenzymes by zone electrophoresis in partly rehydrated polyacrylamide gels is described. Five hundred microm thin polyacrylamide gels are polymerized under standardized conditions. After polymerization the gels are washed thoroughly with distilled water to remove any unreacted monomers, catalysts or still soluble polymers. The washed gels are then impregnated with 0.5% Tween 20 and dried. Before electrophoresis the dry gels are rehydrated to a thickness of 250 microm, which makes up 50% of the original gel volume. Rehydration is carried out by use of a degassed buffer solution. This method permits the demonstration of the isoenzymes of alcohol-dehydrogenase class I and II in man and allows quantitative determination.


Subject(s)
Alcohol Dehydrogenase/analysis , Electrophoresis, Polyacrylamide Gel/methods , Acrylic Resins , Electrophoresis, Starch Gel , Fluid Therapy , Humans
11.
Anat Embryol (Berl) ; 190(3): 201-9, 1994 Sep.
Article in English | MEDLINE | ID: mdl-7818092

ABSTRACT

An overview of our current knowledge of the hepatic lymph vessels is given, and the different lymph node stations that are related to the liver are described. The lymphatics of the liver itself can be divided into a superficial and a deep system. The superficial vessels are mainly situated in the liver capsule, the deep ones follow the triads of Glisson or the efferent hepatic veins. There are no direct communications between spaces in the liver parenchyma and the first lymphatic capillaries, which end blindly in the surrounding connective tissue. Nevertheless, the perisinusoidal space of Disse, the space of Mall, directly adjacent to the outer limiting plate of the parenchyma, and the space of Comparini, surrounding the sublobular hepatic veins can be regarded as prelymphatic spaces from which the hepatic lymph could originate. The extracellular matrix in the space of Disse is apparently continuous with the extraparenchymal areas of the connective tissue. Collagens and proteoglycans offer a morphological pathway for the transport of fluid, the physiological prerequisites of which are discussed.


Subject(s)
Liver/anatomy & histology , Lymphatic System/anatomy & histology , Collagen/analysis , Extracellular Matrix/chemistry , Glycoproteins/analysis , Humans , Liver/chemistry , Liver/physiology , Lymphatic System/physiology , Proteoglycans/analysis
12.
J Histochem Cytochem ; 42(7): 855-9, 1994 Jul.
Article in English | MEDLINE | ID: mdl-8014468

ABSTRACT

A new method for electrophoretic separation of the isoforms of malate dehydrogenase in microdissected tissue samples was applied to rat liver. The intra-acinar activity profiles of cytosolic (cMDH) and mitochondrial (mMDH) malate dehydrogenase were determined in male and female control animals and in animals fasted for 84 hr. Measurements were carried out on lyophilized liver tissue samples of 50-100 ng from the whole length of the sinusoid. The results showed that both in fed and fasted animals, mMDH activity was almost evenly distributed throughout the acinus in livers of both sexes. cMDH showed higher activity in the periportal area compared with the perivenous area by a factor of approximately 1.35 in all animals studied. Our results favor a slightly higher capacity of the malate-aspartate shuttle in the periportal area in both fed and fasted animals. Furthermore, the distribution pattern of mMDH suggests that this isoenzyme is not a marker for the zonation of the oxidative metabolism in the liver acinus.


Subject(s)
Isoenzymes/metabolism , Liver/enzymology , Malate Dehydrogenase/metabolism , Mitochondria, Liver/enzymology , Animals , Cytosol/enzymology , Electrophoresis/methods , Fasting/metabolism , Female , Male , Microchemistry , Rats , Rats, Wistar
13.
Histochem J ; 26(7): 597-600, 1994 Jul.
Article in English | MEDLINE | ID: mdl-7960937

ABSTRACT

A newly developed technique was used for the electrophoretic separation of lactate dehydrogenase (LDH) isoenzymes from lyophilized tissue samples in the nanogram range. In this study portions of 10-200 ng from the myocardium and the conducting system of cattle, sheep, pig and man were microdissected and analysed. In the heart tissues of cattle, sheep and pig, the isoforms LDH1, LDH2 and LDH3 were detected in species-specific varying amounts. In all these animals, the conducting system is marked by high LDH1 activity, which is present at a ratio of about 2:1 compared with the myocardium. The values in man, however, differ from these values, but this might be due to post-mortem changes. The findings are discussed with respect to possible aerobic-anaerobic functions.


Subject(s)
Heart Conduction System/enzymology , Isoenzymes/analysis , L-Lactate Dehydrogenase/analysis , Myocardium/enzymology , Adult , Animals , Cattle , Electrophoresis, Polyacrylamide Gel , Female , Humans , Male , Middle Aged , Sheep , Swine
14.
Histochemistry ; 101(4): 271-5, 1994 Apr.
Article in English | MEDLINE | ID: mdl-7928410

ABSTRACT

In order to evaluate the impact of tissue oxygenation on the distribution pattern of lactate dehydrogenase isoenzymes, activities of the isoenzymes were measured in microdissected samples of bovine tissue. A highly sensitive ultrathin-layer electrophoretic technique was used to determine the distribution pattern of lactate dehydrogenase isoenzymes in basal, intermediate and superficial layers of the epithelium of central and peripheral cornea and in the epithelium of the bulbar conjunctiva. Measurements revealed almost homogeneous intraepithelial distribution patterns of lactate dehydrogenase isoenzymes in both tissues. In the cornea the lactate dehydrogenase isoenzymes 4 and 5, which are regarded to be specialized for anaerobic glucose metabolism, were found to predominate. In the well-oxygenated conjunctival epithelium most of the activity could be ascribed to the lactate dehydrogenase isoenzyme 3. In contrast to the isoenzymatic activities, total activity of lactate dehydrogenase was inhomogeneously distributed; maximum activities were found in the basal layer of corneal epithelium and in the intermediate layer of conjunctival epithelium. The results indicate that oxygen supply is relevant rather for the intraepithelial distribution of total enzyme activity than for the expression of lactate dehydrogenase isoenzymes.


Subject(s)
Conjunctiva/enzymology , Cornea/enzymology , L-Lactate Dehydrogenase/analysis , Animals , Cattle , Electrophoresis/methods , Epithelium/enzymology , Female , Isoenzymes , L-Lactate Dehydrogenase/metabolism , Microchemistry/methods , Oxygen/metabolism
15.
Histochemistry ; 98(5): 311-5, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1283161

ABSTRACT

Using qualitative and microquantitative histo-chemical techniques, alcohol dehydrogenase and aldehyde dehydrogenase activity was studied in the gastric mucosa of male and female rats. Alcohol dehydrogenase was demonstrated by staining reactions with maximum activity in surface and neck cells and with clearly weaker activity also in parietal cells. Aldehyde dehydrogenase could be detected in surface and neck cells, and also to a comparable degree in the parietal cells. Quantitative analyses of microdissected samples yielded high values for alcohol dehydrogenase activity exclusively in the superficial part of the gastric mucosa, whereas low-Km aldehyde dehydrogenase activity showed a decreasing gradient from the surface to the deeper parts of the mucosa. Sex differences could not be confirmed.


Subject(s)
Alcohol Dehydrogenase/metabolism , Aldehyde Dehydrogenase/metabolism , Gastric Mucosa/enzymology , Animals , Female , Gastric Mucosa/anatomy & histology , Histocytochemistry , Kinetics , Male , Rats , Rats, Wistar , Sex Characteristics , Staining and Labeling
16.
Enzyme ; 46(1-3): 8-32, 1992.
Article in English | MEDLINE | ID: mdl-1289084

ABSTRACT

The development of liver parenchyma starts from entodermal cells which grow out from the gut into the mesenchyma of the septum transversum. In the definitive organ this close association of epithelial cells (hepatocytes) and mesenchyma-derived nonparenchymal cells is maintained. The liver, and with it each hepatocyte, acts in two directions: the vascular poles of the hepatocytes serve in an ingestive sense, while at their biliary poles secretory functions are exerted. Hepatic microvascularization comprises two afferent vessels (arterial and portal terminal branches), the sinusoids and the terminal hepatic venule. Sinusoidal cells surround the capillaries but also have highly specialized functions with regard to filtration, phagocytosis, fat storage and defense. The autonomic innervation plays an important role in the regulation of metabolic functions. Above the cellular level the proper architecture of the liver parenchyma has been the object of controversial discussions for centuries. The concept of the liver lobule, the portal unit, the liver acinus and other structures are presented and discussed. Finally, the liver parenchyma is described as an irregular interdigitating system of regions related to the terminal blood vessels.


Subject(s)
Liver/cytology , Animals , Humans , Liver/anatomy & histology , Liver/physiology , Liver Circulation , Microcirculation
17.
Gastroenterology ; 101(6): 1716-23, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1955136

ABSTRACT

The intraacinar activity profiles of alcohol dehydrogenase and the aldehyde dehydrogenases (I, I plus II, and total) were determined, using liver biopsy samples from eight male and eight female patients. Microchemical assays were performed in microdissected tissue samples from the whole length of the sinusoid. Alcohol dehydrogenase activity in men less than 53 years of age showed a maximum in the intermediate zone, whereas in women less than 50 years of age an increase in the gradient toward the perivenous zone was observed. Furthermore, alcohol dehydrogenase activity in the livers of women was significantly higher than in men. After the age of 53 in men and 50 in women, the sex specificity of the distribution profiles was no longer apparent. The intraacinar profiles of aldehyde dehydrogenase isoenzymes showed only minor variations in the different groups; they were not statistically significant. This is also true for low-Michaelis constant (Km) aldehyde dehydrogenase, which is most important for acetaldehyde oxidation in vivo. Thus, of the variations in zonal heterogeneity of ethanol-degrading enzymes, it is mainly the activity of alcohol dehydrogenase that may contribute to the sex- and age-related susceptibility of liver parenchyma.


Subject(s)
Alcohol Dehydrogenase/metabolism , Aldehyde Dehydrogenase/metabolism , Liver/enzymology , Adolescent , Adult , Age Factors , Biopsy , Female , Humans , In Vitro Techniques , Liver/pathology , Male , Middle Aged , Sex Factors
18.
J Histochem Cytochem ; 39(8): 1121-4, 1991 Aug.
Article in English | MEDLINE | ID: mdl-1856459

ABSTRACT

In adult male and female rat liver, the activity of NAD(+)-and NADP(+)-dependent glutamate dehydrogenase (GDH) was microquantitatively measured in tissue samples of 50-150 ng, microdissected continuously along the sinusoidal length. Total activity of GDH with NAD+ as co-factor was found to be higher by a ratio of about 1:2.3 than with NADP+. All intra-acinar enzyme profiles, irrespective of sex, showed an increasing gradient of GDH activity from the periportal beginning to the perivenous end. These findings are at variance with the immunohistochemical localization of GDH in rat liver. The microquantitative GDH profiles with higher perivenous values could indicate a more pronounced glutamine synthesis in Zone 3 of the liver acinus.


Subject(s)
Glutamate Dehydrogenase/metabolism , Liver/enzymology , NADP/metabolism , NAD/metabolism , Animals , Female , Kinetics , Male , Rats , Rats, Inbred Strains
20.
Histochemistry ; 95(4): 365-71, 1991.
Article in English | MEDLINE | ID: mdl-2022487

ABSTRACT

Using techniques of microdissection and microassay as well as qualitative histochemistry the activity and intra-acinar distribution of G6PDH and ME were studied on selected days of pregnancy in the rat. Both enzymes show distinct fluctuations during the course of pregnancy in keeping with changes in hepatic lipogenesis. Marked increases in activity are seen as early as the 4th day, while highest values are attained on day 20, with a predominant perivenous induction. On day 22, just before parturition a sharp decrease of both enzyme activities with a flattening of the periportal/perivenous gradient was detected. G6PDH shows proportionally considerably larger increases and more distinct changes in zonation. The perivenous fluctuations in G6PDH activity of late gestation are supposed to be caused primarily by insulin. Although estrogen is known to induce both enzymes, the temporal changes in enzyme activity in pregnancy cannot be related to the action of estrogen alone. The changes in enzyme activity, however, correspond well to those of progesterone, and although no direct action of progesterone on these enzymes has yet been proposed, further work on its effects on enzyme activity and distribution is indicated.


Subject(s)
Glucosephosphate Dehydrogenase/metabolism , Liver/enzymology , Malate Dehydrogenase/metabolism , Pregnancy, Animal/metabolism , Animals , Estrogens/metabolism , Female , Histocytochemistry , Insulin/metabolism , Pregnancy , Progesterone/metabolism , Rats , Rats, Inbred Strains , Time Factors
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