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1.
Plant Biol (Stuttg) ; 24(7): 1186-1197, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35869655

ABSTRACT

The occurrence of hot drought, i.e. low water availability and simultaneous high air temperature, represents a severe threat to ecosystems. Here, we investigated how the 2018 hot drought in Central Europe caused a tipping point in tree and ecosystem functioning in a Scots pine (Pinus sylvestris L.) forest in southwest Germany. Measurements of stress indicators, such as needle water potential, carbon assimilation and volatile organic compound (VOC) emissions, of dominant P. sylvestris trees were deployed to evaluate tree functioning during hot drought. Ecosystem impact and recovery were assessed as ecosystem carbon exchange, normalized difference vegetation index (NDVI) from satellite data and tree mortality data. During summer 2018, needle water potentials of trees dropped to minimum values of -7.5 ± 0.2 MPa, which implied severe hydraulic impairment of P. sylvestris. Likewise, carbon assimilation and VOC emissions strongly declined after mid-July. Decreasing NDVI values from August 2018 onwards were detected, along with severe defoliation in P. sylvestris, impairing ecosystem carbon flux recovery in 2019, shifting the forest into a year-round carbon source. A total of 47% of all monitored trees (n = 368) died by September 2020. NDVI recovered to pre-2018 levels in 2019, likely caused by emerging broadleaved understorey species. The 2018 hot drought had severe negative impacts on P. sylvestris. The co-occurrence of unfavourable site-specific conditions with recurrent severe droughts resulted in accelerated mortality. Thus, the 2018 hot drought pushed the P. sylvestris stand towards its tipping point, with a subsequent vegetation shift to a broadleaf-dominated forest.


Subject(s)
Pinus sylvestris , Volatile Organic Compounds , Droughts , Ecosystem , Forests , Trees , Carbon , Water
2.
J Histochem Cytochem ; 28(1): 45-6, 1980 Jan.
Article in English | MEDLINE | ID: mdl-6153192

ABSTRACT

The cell membrane and X bodies of histiocytes X from two cases of eosinophilic granuloma were stained by nonspecific esterase. The results show that histiocytes X possess a cell membrane exoenzyme similar to that of other histiocytes, such as alveolar macrophages, but the role of the X body as related to enzyme activity remains an unknown.


Subject(s)
Esterases/analysis , Histiocytosis, Langerhans-Cell/enzymology , Cell Membrane/ultrastructure , Cytoplasmic Granules/ultrastructure , Histiocytosis, Langerhans-Cell/pathology , Humans , Microscopy, Electron , Staining and Labeling
3.
Opt Express ; 4(2): 121-8, 1999 Jan 18.
Article in English | MEDLINE | ID: mdl-19396265

ABSTRACT

We perform high-intensity pulse propagation experiments in semiconductors. On a free exciton resonance, we demonstrate coherent Self-Induced Transmission. Tuning the laser towards higher energy, thus exciting continuum states, the degree of transmission is reduced. The pulse breakup vanishes. Increasing the pulse intensity by several orders of magnitude, pulse breakup can be observed again.

4.
J Chromatogr A ; 892(1-2): 47-55, 2000 Sep 15.
Article in English | MEDLINE | ID: mdl-11045479

ABSTRACT

Classical silica technology has reached its limit with respect to an ultimate minimum particle size of about 2 microm in diameter. Here, a novel process is presented which allows one to synthesize porous silica beads and control their particle diameter in situ, within the range of 0.2-2.0 microm. As a result, no sizing is required and losses of silica are avoided. Furthermore, the process enables one to control in situ the pore structural parameters and the surface chemistry of the silica beads. Even though surface funtionalized silicas made according to this process can principally be applied in fast HPLC the column pressure drop will be high even for short columns. In addition, the column efficiency, expressed in terms of the theoretical plate height is about H-2d(p) in the best case and limited by the A and C term of the Van Deemter equation. In other words the gain in total plate number when using 1-2 microm silica beads in short columns is minimal as compared to longer columns packed with 5 microm particles. Capillary electrochromatography (CEC) as a hybrid method enables the application of micron size as well as submicron size particles. This consequently enhances column efficiency by a factor of 5-10 when compared to HPLC. The use of short CEC columns packed with submicron size silicas provides the basis for fast and efficient miniaturized systems. The most significant feature of CEC as compared to HPLC is that the former allows one to resolve polar and ionic analytes in a single run. An alternative method for miniaturization is capillary electrophoresis (CE) which generates extremely high efficiencies combined with fast analysis. Its application, however, is limited to ionic substances.


Subject(s)
Chromatography, Liquid/methods , Chromatography, Micellar Electrokinetic Capillary/methods , Particle Size
5.
Eur J Gastroenterol Hepatol ; 9(3): 293-8, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9096433

ABSTRACT

OBJECTIVE: To assess the feasibility of developing a model of overt portal-systemic encephalopathy (PSE) in rats with a surgically constructed portacaval anastomosis (PCA). DESIGN: The ability of increasing the load of nitrogenous substances in the gastrointestinal tract and/or further decreasing hepatocellular function to induce overt encephalopathy in rats with a PCA was determined. METHODS: The load of nitrogenous substances in the gastrointestinal tract was increased by feeding a pure horse-meat diet or by gavaging with blood. Partial hepatectomy and the induction of cirrhosis were used to decrease hepatocellular function further. The severity of encephalopathy was assessed using a neurobehavioural scale. RESULTS: Overt encephalopathy was not induced in rats by a PCA alone, by a PCA plus a horse-meat diet, by a PCA plus induction of cirrhosis, or by a PCA plus a 50% hepatectomy. Predominantly mild, but overt, encephalopathy was induced in rats with a PCA alone by gavaging with blood and a higher incidence of more severe overt encephalopathy was induced in rats with a PCA combined with either cirrhosis or partial hepatectomy by gavaging with blood. Although these models of PSE were associated in some instances with plasma ammonia concentrations about 25 times higher than normal, no seizures were observed. CONCLUSION: A syndrome that resembles overt PSE in humans can be induced in the rat with a PCA by further reducing hepatocellular function and also gavaging with blood. Although the rat with a PCA has been. extensively used as a model in studies relating to the pathogenesis of PSE, a syndrome resembling overt PSE in humans cannot readily be induced in rats with a PCA.


Subject(s)
Disease Models, Animal , Hepatic Encephalopathy/etiology , Portacaval Shunt, Surgical , Ammonia/blood , Animals , Blood Urea Nitrogen , Body Weight , Feasibility Studies , Hepatectomy , Liver Cirrhosis, Experimental/chemically induced , Male , Organ Size , Rats , Rats, Sprague-Dawley
6.
Hepatogastroenterology ; 29(6): 232-5, 1982 Dec.
Article in English | MEDLINE | ID: mdl-7152456

ABSTRACT

Rats with a total portacaval anastomosis (PCA, PC-SS) develop preneoplastic and neoplastic lesions in the urinary tract. In contrast to this, animals with a modified shunt (mPCA) do not develop these lesions. To evaluate the possible role of bile acids excreted with the urine for tumor development, total plasma bile acid concentration and 24 hours urinary bile acid excretion were measured radioimmunologically in rats with total and modified shunts. Additionally the renal 14C-glycocholic acid excretion into the urine was studied after oral administration. Total plasma BA increased from 4.89 +/- 1.0 mumol/l in sham-operated controls to 77.7 +/- 39 mumol/h in PCA and 52.9 +/- 36.7 mumol/l in mPCA rats (p less than 0.001 vs controls, PCA vs mPCA = n.s.). Urinary bile acid excretion rose from 0.2 +/- 0.29 mumol/24 hours in controls to 4.47 +/- 4.49 in PCA and 2.55 +/- 2.22 mumol/24 hours in mPCA rats (p less than 0.001 vs control; PCA vs mPCA = n.s.) 14C-glycocholic acid was excreted within 24 hours into the urine in 13.6 +/- 11.5% in PCA and 26.3 +/- 23.5% of the administered dose in mPCA-rats (controls; 2.98 +/- 0.67%, p less than 0.001; PCA vs mPCA = n.s.). Since renal BA-excretion is similar in both shunted groups, urinary BA does not seem to be of primary significance for cancer development in the urinary tract of totally shunted rats.


Subject(s)
Bile Acids and Salts/urine , Portacaval Shunt, Surgical/adverse effects , Urologic Neoplasms/etiology , Animals , Bile Acids and Salts/blood , Carcinoma/pathology , Enterohepatic Circulation , Glycocholic Acid/urine , Kidney Neoplasms/pathology , Male , Papilloma/pathology , Rats , Urinary Bladder Neoplasms/pathology
7.
Dtsch Med Wochenschr ; 139(33): 1647-52, 2014 Aug.
Article in German | MEDLINE | ID: mdl-25093951

ABSTRACT

BACKGROUND AND AIM: Chronic-thromboembolic pulmonary hypertension (CTEPH) is a serious complication of acute pulmonary embolism (PE). In untreated patients prognosis is poor. It depends on WHO-functional class. A delay from onset of symptoms and diagnosis can lead to a further worsening of prognosis. A pulmonary endarterectomy is the treatment of choice. We aimed to evaluate the time delay from onset of symptoms to diagnosis and the WHO-functional class at primary diagnosis in patients with CTEPH. PATIENTS AND METHODS: Retrospective analysis of data from 70 monocentrically registered patients (48 women, 22 men, mean age 66,2 years  ± â€Š13,8 years) with confirmed CTEPH from the pulmonary hypertension expert center Missionsärztliche Klinik. Diagnostic work-up was performed according to the current guidelines. RESULTS: Mean delay from onset of symptoms to diagnosis of CTEPH was 18 ±â€Š26 months. Time delay was only slightly shorter in patients with a history of PE (n = 56; 81 %) than in patients without a history of PE (n = 13; 19 %): 16,9  ± â€Š23,8 vs. 23,5 â€Š± â€Š36,9 months. Time delay was higher in patients who received vasoactive medication before the first contact with a PH expert center and in patients who were classified as technically not suitable for a thrombendarterectomy. 38 patients with a history of acute PE did not have a period without symptoms. In 18 patients symptoms had transiently gone after PE. More than 70 % presented in WHO functional class III or IV. CONCLUSION: Time delay between onset of symptoms and diagnosis of CTEPH and referral to a PH expert center is long and the majority of patients presented in WHO-functional class III or IV. Prognosis is poor in untreated patients and getting worse with a higher WHO-functional class. For this reason, and because CTEPH can be cured by a pulmonary endarterectomy, each patient with suspected PH should be referred to a PH expert center to exclude CTEPH.


Subject(s)
Delayed Diagnosis , Hypertension, Pulmonary/diagnosis , Hypertension, Pulmonary/surgery , Pulmonary Embolism/diagnosis , Pulmonary Embolism/surgery , Aged , Algorithms , Chronic Disease , Cooperative Behavior , Embolectomy , Endarterectomy , Female , Germany , Humans , Hypertension, Pulmonary/mortality , Interdisciplinary Communication , Male , Middle Aged , Prognosis , Pulmonary Artery/surgery , Pulmonary Embolism/complications , Pulmonary Embolism/mortality , Referral and Consultation , Retrospective Studies , Survival Rate , Thrombectomy
8.
Neuroscience ; 169(1): 449-54, 2010 Aug 11.
Article in English | MEDLINE | ID: mdl-20451587

ABSTRACT

G protein-coupled opioid receptors undergo desensitization after prolonged agonist exposure. Recent in vitro studies of mu-opioid receptor (MOR) signaling revealed an involvement of phosphoinositide 3-kinases (PI3K) in agonist-induced MOR desensitization. Here we document a specific role of the G protein-coupled class IB isoform PI3Kgamma in MOR desensitization in mice and isolated sensory neurons. The tail-withdrawal nociception assay evidenced a compromised morphine-induced tolerance of PI3Kgamma-deficient mice compared to wild-type animals. Consistent with a role of PI3Kgamma in MOR signaling, PI3Kgamma was expressed in a subgroup of small-diameter dorsal root ganglia (DRG) along with MOR and the transient receptor potential vanilloid type 1 (TRPV1) receptor. In isolated DRG acute stimulation of MOR blocked voltage-gated calcium currents (VGCC) in both wild-type and PI3Kgamma-deficient DRG neurons. By contrast, following long-term opioid administration the attenuating effect of MOR was strongly compromised in wild-type DRG but not in PI3Kgamma-deficient DRG. Our results uncover PI3Kgamma as an essential modulator of long-term MOR desensitization and tolerance development induced by chronic opioid treatment in sensory neurons.


Subject(s)
Class II Phosphatidylinositol 3-Kinases/physiology , Morphine/pharmacology , Narcotics/pharmacology , Receptors, Opioid, mu/drug effects , Sensory Receptor Cells/enzymology , Animals , Calcium Channels/physiology , Cells, Cultured/enzymology , Cells, Cultured/physiology , Class II Phosphatidylinositol 3-Kinases/deficiency , Class II Phosphatidylinositol 3-Kinases/genetics , Drug Tolerance/physiology , Ganglia, Spinal/cytology , Mice , Mice, Knockout , Morphine/administration & dosage , Morphine/therapeutic use , Narcotics/administration & dosage , Narcotics/therapeutic use , Nociceptors/drug effects , Nociceptors/physiology , Patch-Clamp Techniques , Rats , Rats, Wistar , Reaction Time/drug effects , Recombinant Fusion Proteins/physiology , Sensory Receptor Cells/drug effects , Sensory Receptor Cells/physiology , TRPV Cation Channels/drug effects , TRPV Cation Channels/physiology
13.
Planta ; 152(6): 562-4, 1981 Oct.
Article in English | MEDLINE | ID: mdl-24301161

ABSTRACT

Biosynthetic studies with cell-free extracts from Aloe arborescens Mill. demonstrate the transfer of the glucose moiety from UDP-glucose to aloe emodin anthrone, forming the C-glycosidic linkage in the anthracene derivative aloin. The pH-dependence and the specificity of UDP-glucose and aloe emodin anthrone for the biosynthesis of the C-glycosidic bond in aloin are shown.

14.
Arch Tierernahr ; 46(3): 295-304, 1994.
Article in English | MEDLINE | ID: mdl-7619004

ABSTRACT

Artificially dried ryegrass, untreated and ammonia-treated wheat straw were ground and incubated in nylon bags in the rumen of three sheep each fed with diets based on roughage or concentrate. Dry matter degradability, the concentration and the release of the trace elements Cu, Fe, Mn and Zn from the incubated feeds were measured after 0 (washing loss), 6, 12, 24, 48 and 72 h rumen incubation time. Dry matter degradability, trace element concentration and their release were significantly influenced by the kind of incubated feeds, incubation time and feeding of sheep. Cu- (1.8-6.9 mg kg-1 DM) and Zn concentrations (36-103 mg kg-1 DM) of straw residues in the bags were much higher than those of original straw (1.2-1.6 and 8.1-9.9 mg kg-1 DM resp.). The inflow of Cu and Zn in the bags containing straw residues was higher than their release. The Cu-, Fe- and Mn-release from ryegrass was similar to the dry matter degradability, but the Zn-release was much lower.


Subject(s)
Animal Feed , Diet/veterinary , Rumen/metabolism , Sheep/metabolism , Trace Elements/metabolism , Ammonia/pharmacology , Animals , Copper/metabolism , Food Handling , Iron/metabolism , Lolium/metabolism , Manganese/metabolism , Time Factors , Triticum/drug effects , Triticum/metabolism , Zinc/metabolism
15.
Arch Tierernahr ; 39(7): 667-74, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2783032

ABSTRACT

The breed of horses took a significant effect on the Pb content of animals with a normal Pb supply. Warm-blooded horses stored more Pb in skeleton, kidneys, liver and cerebrum than heavy horses. The sex only had the trend of influencing the Pb status. Mares with a normal Pb supply incorporated more Pb than geldings. Age only took a slight effect on the skeleton. Older horses stored more Pb in the metatarsal bone than younger ones. The Pb content of horse meat was not influenced by Pb exposure. Pb was not additionally deposited in the musculature. The Pb offer of the living area took a significant effect on the Pb status of horses. Skeleton, liver and kidneys indicated the site-specific influences significantly.


Subject(s)
Aging , Animal Nutritional Physiological Phenomena , Breeding , Environmental Exposure , Lead/analysis , Sex Characteristics , Animals , Female , Germany, East , Horses , Housing, Animal , Hungary , Male , Organ Specificity , Poland
16.
Acta Hepatogastroenterol (Stuttg) ; 23(1): 31-40, 1976 Feb.
Article in English | MEDLINE | ID: mdl-769471

ABSTRACT

Investigations were performed in rats with portacaval anastomosis (PCA) in order to measure hepatic hemodynamics and cardiac output (CO) 3, 6, 14 and 28 days after operation under pentobarbitone anesthesia using the flow fraction distribution method (131I-MAA) of CO. The latter was calculated using Vierordt's principle from blood volume (BV) (125RIHSA-dilution method) and ICG-appearance time (ICG-AT) (ear-densitometry). Even 3 days after PCA CO was increased to 38.7 +/- 5.0 (SD) ml/min/100 g b.w. (normal 23.8), due to an increase of BV from 6.3 +/- 1.4 to 7.5 +/- 0.6 ml/100 g b.w. and a decrease of ICG-AT from 3.6 +/- 0.4 to 2.8 +/- 0.5 s. Arterial hepatic flow fraction of CO increased to 8.7 +/- 2.8% (control: 5.5 +/- 2.4%). Changes could be observed up to day 28. Hepatic blood flow per g liver tended to stabilize but was still decreased at day 28: 1.5 +/- 0.6 ml/min/g liver (control: 2.0 +/- 0.3). The typical hemodynamic changes in human liver cirrhosis can be reproduced by PCA alone. They are considered to be compensatory mechanisms for a reduced portal liver blood flow, which are not found to compensate completely.


Subject(s)
Liver Circulation , Portacaval Shunt, Surgical , Animals , Blood Circulation Time , Blood Pressure , Blood Volume , Endotoxins/blood , Hypertension, Portal/physiopathology , Liver Cirrhosis, Experimental/physiopathology , Male , Radioisotope Dilution Technique/methods , Rats , Time Factors
17.
Acta Hepatogastroenterol (Stuttg) ; 22(1): 29-35, 1975 Feb.
Article in English | MEDLINE | ID: mdl-1119301

ABSTRACT

Morphological investigations by lightmicroscopy were performed to evaluate the influence of an altered liver RES-function state on the course of Gal-N-hepatitis. There was a good correlation between the biochemical data and the morphological alterations. The simultaneous infusion of Gal-N 1 g/kg b.w. and carbon particles (2.6 mg/100 g b.w) into the portal vein was followed by subtotal necrosis of the liver and Sanarelli-Shwartzmann-phenomenon. Signs of RES-activity were nearly absent. 8 days after pretreatment with carbon, Gal-N application did not produce Gal-N hepatitis; 21 days after carbon infusion the morphological changes normally found after Gal-N application were present. The morphological studies confirm the concept that an altered RES-function state is a very important factor for the development of liver cell necrosis.


Subject(s)
Chemical and Drug Induced Liver Injury/physiopathology , Liver/physiopathology , Mononuclear Phagocyte System/physiopathology , Animals , Carbon/pharmacology , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/prevention & control , Galactosamine , Ink , Kupffer Cells , Necrosis , Phagocytosis , Premedication , Rats , Rats, Inbred Strains , Shwartzman Phenomenon , Time Factors
18.
Planta ; 187(1): 48-52, 1992 Apr.
Article in English | MEDLINE | ID: mdl-24177965

ABSTRACT

The apoplasmic and symplasmic iron pools were determined in roots and leaves of Lycopersicon esculentum Mill. cv. Bonner Beste and its mutant chloronerva. The mutant is auxotrophic for the ubiquitous plant constituent nicotianamine (NA) and exhibits an impaired iron metabolism. Formation of apoplasmic iron pools in roots was dependent on the iron source in the nutrient solution. With Fe-ethylenediaminedi-(2-hydroxyphenylacetate) (FeEDDHA) only a very small apoplasmic iron pool was formed in the roots of both genotypes. Plants grown with FeEDTA increased their apoplasmic iron pool with increasing exogenous iron concentrations in the nutrient solution. The size of the apoplasmic pools in roots did not differ between the wild-type and the mutant (about 85 µmol Fe · g(-1) DW). By contrast, the symplasmic iron concentrations in roots and leaves of the mutant were significantly higher when compared to the wild-type. An exogenous NA supply to the leaves of the mutant reduced the high symplasmic iron concentrations to the level of the wild-type. Mutant leaves exhibited a gradient of symplasmic iron concentrations depending on the developmental age of the leaves. The oldest leaves contained considerably more symplasmic iron than the youngest. The results demonstrate that the apparent iron deficiency of the mutant is not the consequence of an impaired iron transport from the apoplasm to the symplasm. Therefore, it is concluded that NA is not required for the transport of Fe(II) through the plasmalemma into the cell.

19.
Arch Tierernahr ; 31(10): 697-704, 1981 Oct.
Article in German | MEDLINE | ID: mdl-7198901

ABSTRACT

The influence of copper deficiency on the reproduction performance of cows has not often been investigated. In two habitats feeding cows with mineral mixtures rich in copper resulted in a significant reduction of the aperiodically extended sexual cycles. The beginning of the first visible symptoms of heat, the period between gravidities, the duration of gravidity, the birth weight of the calves and the Cu-content of the colostrum remained uninfluenced by Cu-supply. The liver weight increase of the calves from cows without Cu-supplement during gravidity was by 5% lower during the first 90 days of life than that of the offspring of cows with additional intrauterine Cu-supply (p greater than 0.05). The mineral mixture increased the milk yield by 0.4 resp. 0.5 kg and the milk fat content by 0.10 resp. 0.13%. This resulted in an excess production of 32 resp. 62 g milk fat per cow and day of the experiment (p greater than 0,05).


Subject(s)
Cattle/physiology , Copper/deficiency , Milk/metabolism , Reproduction , Animals , Body Weight/drug effects , Copper/pharmacology , Diet , Estrus/drug effects , Female , Lactation , Lipid Metabolism , Milk/analysis , Organ Size/drug effects , Pregnancy , Reproduction/drug effects
20.
Arch Tierernahr ; 31(4): 299-305, 1981 Apr.
Article in German | MEDLINE | ID: mdl-7259521

ABSTRACT

The influence of a nutrition poor in Cu on the copper status of dairy cows was investigated with and without Cu-supplementation through the mineral mixture typical of the territory and enriched with Cu. The roughage produced in the territory investigated contained less than 8.0 mg Cu/kg and did not guarantee a Cu supply of the dairy cows meeting their needs. Feeding the mineral mixture rich in Cu improved the Cu-status of the dairy cows, did, however, in one of the territories not result in a Cu-incorporation in the liver that meets the needs. Possibly the reason for this divergent behaviour is an oversufficient S- and Fe-supply. In contrast to this, the Cu-content of the cerebrum of the cows in both territories showed the effect of the Cu in the mineral mixture.


Subject(s)
Brain/metabolism , Cattle/metabolism , Copper/metabolism , Liver/metabolism , Animal Feed/analysis , Animals , Copper/analysis , Copper/deficiency , Copper/therapeutic use , Female , Food, Fortified , Hair/metabolism , Plants, Edible/analysis , Pregnancy
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