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1.
Sci Rep ; 14(1): 7995, 2024 04 05.
Article in English | MEDLINE | ID: mdl-38580701

ABSTRACT

Artificial light at night (ALAN) is known to affect organisms in terrestrial ecosystems and adjacent litoral habitats. In the present study, we tested the effect of ALAN on the spatial distribution of organisms in open waters, using the insect larvae of Chaoborus flavicans as an example. During the day C. flavicans typically hide from visually hunting fish in deep, dark, anoxic waters. On safer nights, they forage in rich subsurface waters. Nighttime field tests revealed that light from an HPS street lamp mounted on a boat anchored in open water attracted planktivorous fish, but deterred planktonic Chaoborus from rich but risky surface waters. Chaoborus did not descend to the safest, anoxic hypolimnion, but remained in hypoxic mid-depth metalimnion, which does not appear to be a perfect refuge. Neither light gradient nor food distribution fully explained their mid-depth residence under ALAN conditions. A further laboratory test revealed a limited tolerance of C. flavicans to anoxia. Half of the test larvae died after 38 h at 9 °C in anoxic conditions. The trade-off between predation risk and oxygen demand may explain why Chaoborus did not hide in deep anoxic waters, but remained in the riskier metalimnion with residual oxygen under ALAN conditions.


Subject(s)
Diptera , Ecosystem , Animals , Light Pollution , Larva , Fishes , Oxygen , Hypoxia , Culicomorpha , Light
2.
Sci Rep ; 13(1): 13556, 2023 08 21.
Article in English | MEDLINE | ID: mdl-37604994

ABSTRACT

Adopting cannibalism substantially affects individual fitness, and recognizing the presence of other cannibals provides additional benefits such as the opportunity to prepare for hunting or defense. This recognition can be facilitated by perceiving conspecific chemical cues. Their role in cannibalistic interactions is less studied than in interspecific predation and it is unclear whether these cues inform individuals of danger or of food availability. Interpretation of these cues is crucial to balance the costs and benefits of anti-predator and feeding strategies, which can directly influence individual fitness. In this study we aimed to test whether damselfly larvae shift towards bolder and more exploratory (cannibalistic) behavior, or become more careful to avoid potential cannibals (as prey) in response to such cues. We conducted behavioral and respiratory experiments with Ischnura elegans larvae to investigate their response to chemical cues from older and larger conspecific larvae. We found that I. elegans larvae decrease their activity and shift their respiratory-related behavior, indicating activation of anti-predator defense mechanisms in response to conspecific chemical cues. Our findings indicate that individuals exposed to conspecific chemical cues balance catching prey with staying safe.


Subject(s)
Cannibalism , Cues , Humans , Animals , Exercise , Food , Larva
3.
Ecotoxicol Environ Saf ; 249: 114372, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36508828

ABSTRACT

Pharmaceuticals used in human medicine contaminate freshwater ecosystems. Chemotherapeutics applied in cancer treatment are found in freshwaters at low concentrations (in the range of ng L-1) which, however, can be toxic or mutagenic to aquatic organisms. The aim of this study was to determine the impact of the alkylating/crosslinking anticancer agents, cyclophosphamide (CP) and cisplatin (CDDP), at the concentration detected in water, on Daphnia magna life history, transcriptome, and proteome. This filter feeding cladoceran is an important member of the aquatic food webs controlling algal biomass and forming basic food for planktivorous fish. Here, observations of the D. magna growth rate, age at first reproduction, and the number of eggs produced were performed in the presence of CP or CDDP. The D. magna proteins and RNA were isolated and analysed by mass spectrometry and the mRNA-seq method, respectively. Five generations of contact with the pharmaceuticals in question significantly influenced the D. magna life history parameters with the growth rate and number of laid eggs decreased, whereas age at first reproduction was increased. A decrease in survivorship was observed when daphnids were exposed to CP. These changes are the result of modifications in the gene/transcript expression followed by differences in the proteome profile in comparison to the untreated control. The proteome changes were generally in accordance with the modified transcriptome. The ecotoxicogenomics approach makes it possible to get closer to a complete picture of the influence of CP and CDDP on Daphnia. We have gathered evidence that animals in the presence of anticancer pharmaceuticals attempt to cope with permanent stress by changing their proteome and transcriptome profile. Additionally, our analyses indicate that CDDP showed a stronger effect on tested organisms than CP.


Subject(s)
Daphnia , Water Pollutants, Chemical , Humans , Animals , Daphnia/genetics , Proteome , Ecosystem , Water Pollutants, Chemical/toxicity , Cyclophosphamide/toxicity , Cisplatin , Pharmaceutical Preparations , Reproduction
4.
Ann Agric Environ Med ; 29(4): 502-512, 2022 Dec 27.
Article in English | MEDLINE | ID: mdl-36583316

ABSTRACT

INTRODUCTION AND OBJECTIVE: Hazel, alder, birch, and poplar pollen allergens are a common cause of pollen allergies. In a temperate climate, wind-pollinated plants are characterized by a seasonal pollen release cycle associated with the seasons of the year and weather conditions. Therefore, the aim of the present study was to assess the course of pollen seasons of some allergenic plants and to determine the effect of meteorological factors on the content of pollen grains in the bioaerosol in 2021 in Kielce, Poland. MATERIAL AND METHODS: In relation to selected meteorological parameters, the length of the total and main pollen season, the sum of daily pollen grain concentrations in the season, the peak pollen concentration, and the number of days with values exceeding the species-specific threshold concentrations, were determined. RESULTS: Hazel and alder pollen were the first to appear in the air of Kielce. The longest pollen season was observed for birch, while hazel was characterized by the shortest season. The alder pollen release was intense, with the highest maximum concentration of pollen grains. The study revealed a significant influence of the maximum air temperature on the dynamics of hazel, alder and poplar pollen release. Birch pollen release was significantly correlated with the average air humidity. The concentration of alder and birch pollen grains also depended on rainfall intensity. The wind force had a significant impact on the pollen season of plants. CONCLUSIONS: There were various relationships between the meteorological factors and the content of pollen grains in the air. The wind speed and temperature had the greatest impact on plant pollen release, with birch and alder being particularly sensitive to weather conditions.


Subject(s)
Alnus , Betula , Seasons , Poland , Pollen , Allergens , Meteorological Concepts
5.
Ecol Evol ; 12(8): e9163, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35928798

ABSTRACT

In freshwater environments, one of the challenges aquatic grazers face are periods of suboptimal food quantity and quality. In a life table experiment, the effects of food quantity (a gradient of algae concentration) and quality (a diet of cyanobacteria) on the life histories and resource allocation strategy in Daphnia magna were tested. Growth-related traits were similarly affected under different food regimes while the reproductive strategies differed in animals exposed to low food quantity and quality. The per-clutch investment (clutch volume) did not differ between Daphnia fed with cyanobacteria and underfed mothers, but resources were differently allocated; underfed mothers increased their per-offspring investment by producing fewer, but larger eggs, whereas cyanobacteria-fed mothers invested in a greater number of eggs of smaller size. I argue that both strategies of resource allocation (number vs. size of eggs) may be adaptive under the given food regime. The results of the study show that the cyanobacteria diet-driven fitness losses are comparable to losses caused by food quantity, which is only slightly above the growth capability threshold for Daphnia.

6.
Environ Pollut ; 261: 114135, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32066054

ABSTRACT

The effect of chronic exposure of freshwater cladoceran Daphnia magna to low, environmentally relevant concentrations i.e 4 µgL-1of ibuprofen (a nonsteroidal anti-inflammatory drug) in a laboratory experiment was studied. We observed the key life history traits of first and fifth generation individuals: age and size at first reproduction, number of first clutch eggs and individual growth rate. Moreover, chosen molecular/subcellular markers of experimental animals stress response such as triglyceride content, heat shock proteins (HSP) expression and DNA:RNA ratio were collected. Overall, chronic exposure to ibuprofen had no significant effect on the molecular markers nor on the life history parameters of the Daphnia. It did, however, caused lethal morphological deformities in embryos and juvenile daphnids. Depending on the clonal affiliation, exposure to a low dosage of ibuprofen over five generations resulted in the deformation of ∼3%-∼10% of the first clutch of offspring. Also, up to 90% of females carried at least one deformed embryo. This is the first time that research has revealed such an effect of ibuprofen on D. magna.


Subject(s)
Daphnia , Water Pollutants, Chemical , Animals , Anti-Inflammatory Agents, Non-Steroidal , Female , Ibuprofen , Reproduction
7.
Aquat Toxicol ; 215: 105288, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31526926

ABSTRACT

Pharmaceuticals are used in medical treatment on a large scale and as a waste contaminate freshwater ecosystems. Growing amount of so-called civilization diseases, such as different type of cancer, significantly contribute to this form of pollution. The aim of the present study was to determine how the exposure to chemotherapeutics: cyclophosphamide (CP) and cisplatin (CDDP), at detected in environment concentrations, influence proteome profile, life history and population parameters of naturally setting surface waters Daphnia pulex and Daphnia pulicaria. The parameters important for crustaceans, survivorship and population growth rate, were importantly decreased by CDDP treatment but not influenced by CP. On the contrary, the individual growth rate was affected only by CP and exclusively in the case of D. pulicaria. In both clones treated with CP or CDDP, decreased number of eggs was observed. Interestingly, Daphnia males were less sensitive to tested chemotherapeutic than females. Proteome profile revealed that tested anticancer pharmaceuticals modified expression of some proteins involved in Daphnia metabolism. Moreover, males exposed to CDDP showed increased level of enzymes participating in DNA repair. Summing up, the contaminating environment chemotherapeutics reduced fitness of naturally occurring Daphnia species. In consequence this may affect functioning of the aquatic food webs.


Subject(s)
Antineoplastic Agents/toxicity , Daphnia/genetics , Water Pollutants, Chemical/toxicity , Analysis of Variance , Animals , Cisplatin/toxicity , Cyclophosphamide/toxicity , Daphnia/drug effects , Daphnia/growth & development , Female , Life Cycle Stages/drug effects , Male , Proteins/metabolism , Proteome/metabolism
8.
Anticancer Res ; 39(2): 679-686, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30711945

ABSTRACT

BACKGROUND: Anthraquinones, including emodin, are compounds with numerous pharmacological properties, including anticancer properties. The aim of this study experiment was to examine the effect of emodin, a natural compound present in the roots and rhizomes of Rheum palmatum, on the induction of mitotic catastrophe in cervical cancer cells. MATERIAL AND METHODS: HeLa celIs were treated with different emodin concentrations for 48 h, and cell growth was measured with 3-(4-,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolyl. The cell-cycle distribution and the level of apoptosis were determined by means of flow cytometry, using annexin V-fluorescein isothiocyanate staining and propidium iodide. Morphological changes in the mitotic apparatus were evaluated using optical and confocal microscopy techniques. RESULTS: Emodin induced an increase in the number of polymorphonuclear cells, giant cells, cells with micronuclei, cells with abnormal mitosis and damaged spindle. The reorganization of F-actin depended on the concentration of emodin. With the increase in emodin concentration, inhibition of mitotic activity was demonstrated, which was manifested by a decrease in the mitotic index, mainly in metaphase of the mitotic process and an increase in the number of cells inhibited in the G2/M phase. At the same time, an increase in the number of apoptotic cells was found. CONCLUSION: Emodin leads to death of cervical cancer cells by induction of a mitotic catastrophe.


Subject(s)
Emodin/pharmacology , Mitosis/drug effects , Uterine Cervical Neoplasms/pathology , Actins/metabolism , Anthraquinones/pharmacology , Apoptosis , Cell Cycle/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Cytoskeleton/metabolism , Female , Fluorescein-5-isothiocyanate/chemistry , HeLa Cells , Humans , Micronucleus Tests , Microscopy, Confocal , Neutrophils/cytology , Propidium/chemistry
9.
Environ Toxicol Pharmacol ; 64: 147-154, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30391876

ABSTRACT

Melatonin is a hormone with many different biological activities and therefore seems to be an important factor reducing the harmful effects caused by toxic organophosphorus compounds. In this study, we attempted to evaluate the protective effect of melatonin on liver cells of mice challenged with chemical warfare agent-soman. The study was conducted at the level of ultrastructural and biochemical changes (analysis of the activity of model lysosomal enzymes and assessment of the level of lipid peroxidation). Significant biochemical and ultrastructural changes were found in the studied mouse hepatocytes after administration of soman alone, and soman in combination with melatonin, and the scope of the disclosed changes was dependent on the time of action of the examined factors. Melatonin has shown protective action, shielding liver cells from toxic effects of soman, which may result from its antioxidant properties and stimulation of the lysosomal compartment, the system coordinating the isolation and removal of cell-threatening processes.


Subject(s)
Chemical Warfare Agents/toxicity , Cholinesterase Inhibitors/toxicity , Hepatocytes/drug effects , Melatonin/pharmacology , Protective Agents/pharmacology , Soman/toxicity , Animals , Autophagy/drug effects , Hepatocytes/metabolism , Hepatocytes/ultrastructure , Lipid Peroxidation/drug effects , Lysosomes/metabolism , Male , Mice, Inbred BALB C
10.
J Trace Elem Med Biol ; 50: 167-174, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30262276

ABSTRACT

The aim of this study was to evaluate ultrastructural changes in kidney and liver tissue of chicken embryos exposed in ovo to cadmium. Embryonated eggs were injected on the 4th day of incubation with cadmium at the dose of 0, 2, 4 and 8 µg/egg (80 eggs/group). The samples of kidney and liver tissues were collected from embryos at the 14th and 18th day of incubation (E14 and E18) and at hatching day (D1). The tissue structure was evaluated by transmission electron microscopy (Tecnai G2 Spirit). The results indicate that hepatocytes responded to damage caused by toxic cadmium activity with a significant disturbance in the structure of mitochondria and a considerable expansion of the lysososmal system, while glomerular cells additionally reacted with an increased proliferation of peroxisomes. The range of changes observed on the subcellular level was dependent on the dose of cadmium, embryogenesis stage and cell type.


Subject(s)
Cadmium/toxicity , Mitochondria/drug effects , Mitochondria/metabolism , Animals , Chick Embryo , Chickens , Kidney/drug effects , Kidney/metabolism , Liver/drug effects , Liver/metabolism , Microscopy, Electron, Transmission , Mitochondria/ultrastructure , Peroxisomes/drug effects , Peroxisomes/metabolism
11.
Acta Biochim Pol ; 65(3): 351-358, 2018.
Article in English | MEDLINE | ID: mdl-30148509

ABSTRACT

Although vitamin D is included in the group of fat-soluble vitamins, it must be considered as a prohormone. Its active forms, including calcitriol, have pleiotropic effects and play an important role in the regulation of cell proliferation, differentiation and apoptosis, as well as in hormone secretion, and they demonstrate anti-cancer properties. Since calcitriol delivery can be beneficial for the organism, and Syrian golden hamsters represent a unique experimental model, we decided to investigate its toxicity in this species. In this study, we injected calcitriol intraperitoneally at doses 0 (control), 0.180±0.009 µg/kg and 0.717±0.032 µg/kg. Animal behavior was observed for 72 hrs after injection, and afterwards blood, liver and kidneys were collected for post-mortem examination, electron microscopy, and hematology analyses. The highest dose of calcitriol induced a change in animal behavior from calm to aggressive, and the liver surface showed morphological signs of damage. Following injection of calcitriol, ultrastructural changes were also observed in the liver and kidneys, e.g. vacuolization and increased number of mitochondria. There was also a trend for increased serum levels of aspartate aminotransferase (AST), but not of alanine aminotransferase (ALT) or GGTP (gamma-glutamyl transpeptidase). There was no change in Ca, Mg and P levels, as well as in blood morphology between experimental and control groups. These results indicate that calcitriol at 0.717, but not at 0.180 µg/kg, may induce acute damage to the liver and kidneys, without inducing calcemia. We propose that the hepatotoxic effect of calcitriol in hamster constitutes the primary cause of behavioral changes.


Subject(s)
Calcitriol/toxicity , Kidney/drug effects , Liver/drug effects , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Behavior, Animal/drug effects , Calcitriol/administration & dosage , Cricetinae , Dose-Response Relationship, Drug , Female , Injections, Intraperitoneal , Kidney/physiopathology , Kidney/ultrastructure , Liver/physiopathology , Liver/ultrastructure , Mesocricetus , Microscopy, Electron , Subcellular Fractions/ultrastructure , Toxicity Tests, Acute , gamma-Glutamyltransferase/blood
12.
Anticancer Res ; 38(4): 2037-2044, 2018 04.
Article in English | MEDLINE | ID: mdl-29599321

ABSTRACT

BACKGROUND: Aloe-emodin is an anthraquinone with potential pharmacological properties, including numerous antitumor properties. The purpose of the study was to determine whether aloe-emodin induces mitotic death in cervical cancer cells. MATERIALS AND METHODS: Analysis of morphological changes as surrogate mitotic death indicators in HeLa cells was carried out using optical, fluorescence and electron microscopy. Viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide reduction assay. Cell-cycle analysis was performed using flow cytometry. RESULTS: Aloe-emodin increased the number of multinucleate cells, giant and micronuclear cells. There was a concentration-dependent decrease in the mitotic index with a predominance of cells in the metaphase of the mitotic process and inhibition of division in the G2/M phase of the cell cycle. The presence of cells with abnormal mitosis and cells with injury to the division spindle was also demonstrated. CONCLUSION: Aloe-emodin induces mitotic catastrophe in cervical cancer cells.


Subject(s)
Anthraquinones/pharmacology , Mitosis/drug effects , Uterine Cervical Neoplasms/pathology , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Proliferation/drug effects , Female , G2 Phase/drug effects , HeLa Cells , Humans
13.
Asian Pac J Cancer Prev ; 18(12): 3273-3279, 2017 Dec 29.
Article in English | MEDLINE | ID: mdl-29286219

ABSTRACT

Background: Aloe-emodin belongs to the group of anthraquinones having extremely high biological activity. The aim of this study was to evaluate the range of morphological and biochemical changes in HeLa cells treated with aloe-emodin, especially with regard to the lysosomal compartment. Methods: Marking of lysosomes was performed with neutral red staining for conventional light microscopy and acridine orange staining for confocal microscopy. To evaluate ctivity of lysosomal enzymes and permeability of the lysosomal membrane, spectrophotometric techniques were employed. Results: Aloe-emodin caused increased permeability of lysosomal membranes in HeLa cells, expressed inter alia by extinction of the orange color of acridine orange (lysosomal marker) and in reduction of neutral red uptake by lysosomes. These changes are accompanied by release of cathepsins from the interior of the lysosomes with a simultaneous highly significant increase in their activity in the cytoplasm. Conclusion: The results indicate that aloeemodin can activate lysosomal pathway-dependent apoptosis in HeLa cells.


Subject(s)
Anthraquinones/pharmacology , Apoptosis/drug effects , Cell Proliferation/drug effects , Cytoplasm/metabolism , Lysosomes/metabolism , Cell Survival , Cytoplasm/drug effects , HeLa Cells , Humans , Lysosomes/drug effects
14.
Anticancer Res ; 37(11): 6087-6096, 2017 11.
Article in English | MEDLINE | ID: mdl-29061789

ABSTRACT

BACKGROUND: An example of plant-derived compounds that may be of great importance in oncological therapy is emodin. The aim of this study was to evaluate the range of changes in the lysosomal compartment of HeLa cervical cancer cells treated with emodin. MATERIALS AND METHODS: Changes in the lysosomal compartment were evaluated using microscopic techniques. In order to evaluate the activity of lysosomal enzymes and the permeability of the lysosomal membrane, a spectrophotometric technique was employed. RESULTS: Emodin induced significant changes in the lysosomal compartment, manifesting as an increase in the number of lysosomes, autophagic vacuoles and the activity of lysosomal hydrolases. Emodin exhibited cytotoxic activity against lysosomes through lysosomal membrane damage with possible leaks of lysosomal hydrolases into the cytoplasm. CONCLUSION: Emodin induces degradation processes and promotes the death of tumor cells through a mechanism that occurs with clear involvement of the lysosomal compartment.


Subject(s)
Apoptosis/drug effects , Emodin/pharmacology , Hydrolases/metabolism , Lysosomes/metabolism , Uterine Cervical Neoplasms/pathology , Vacuoles/metabolism , Autophagy/drug effects , Cell Proliferation , Female , Humans , Lysosomes/drug effects , Protein Kinase Inhibitors/pharmacology , Tumor Cells, Cultured , Uterine Cervical Neoplasms/drug therapy , Vacuoles/drug effects
15.
Anticancer Res ; 37(11): 6373-6380, 2017 11.
Article in English | MEDLINE | ID: mdl-29061822

ABSTRACT

BACKGROUND/AIM: To search for new antileukemic agents, the chemical structure of phenytoin was modified. A possible cytotoxic activity of three bromoalkyl phenytoin analogs, methyl 2-(1-(3-bromopropyl)-2,4-dioxo-5,5-diphenylimidazolidin-3-yl) propanoate (PH2), 1-(3-bromopropyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (PH3) and 1-(4-bromobutyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (PH4) on regulated cell death, the cell cycle and cell ultrastructure was assessed. MATERIALS AND METHODS: The experiments were performed in vitro on HL-60 and U937 cells, using flow cytometry and electron microscopy methods. RESULTS: Application of PH2, PH3, and PH4 resulted in cell surface exposure of phosphatidylserine and plasma membrane impairment, caspase-8, -9, and -3/7 activation, dissipation of mitochondrial membrane potential, DNA breakage, cell-cycle disturbance and cell ultrastructural changes. In general, PH3 appeared to be the most active against the leukemia cells, and all bromoalkyl hydantoins, PH2-PH4, were more active in HL-60 cells than in U937 cells. CONCLUSION: The antileukemic activity of the bromoalkyl phenytoin analogs depended on the combination of N-hydantoin substituents and the human cell line used.


Subject(s)
Antineoplastic Agents/pharmacology , Caspases/metabolism , Leukemia/metabolism , Phenytoin/analogs & derivatives , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Cycle/drug effects , Cell Membrane/drug effects , DNA Breaks , Drug Screening Assays, Antitumor , Gene Expression Regulation, Neoplastic/drug effects , HL-60 Cells , Humans , Leukemia/drug therapy , Leukemia/genetics , Membrane Potential, Mitochondrial/drug effects , Molecular Structure , Phenytoin/chemistry , U937 Cells
16.
Prz Menopauzalny ; 15(1): 48-51, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27095959

ABSTRACT

Uterine fibroids are found in almost 20-40% of women of reproductive age. For each woman an individualised treatment method should be applied because the hysterectomy procedure is not a good option in every case. The uterus is an organ necessary not only in reproduction. Its removal may result in: pelvic floor dysfunction and stress urinary incontinence, negative impair on life quality, depressive disorders, increased risk of cardiovascular and neurodegenerative diseases, and higher incidence of neoplastic disease. According to the last scientific reports, selective progesterone receptor modulators are the effective therapeutic option in uterine fibroids in women of reproductive age because progesterone is an important factor in their pathogenesis. Ulipristal acetate (UPA) is a progesterone receptor antagonist. It inhibits cell proliferation and angiogenesis in uterine fibroids and also reduces collagen deposits in extracellular matrix. Significant data concerning ulipristal acetate efficacy have been provided by scientific research, especially from the consecutive PEARL studies. Oral ulipristal acetate effectively and safely controls bleeding and pain in patients with symptomatic fibroids. It reduces fibroid volume and restores quality of life. The results of UPA long-term intermittent treatment are largely maintained during the off-treatment periods.

17.
Evolution ; 63(7): 1867-78, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19473405

ABSTRACT

Rising temperatures associated with global warming present a challenge to the fate of many aquatic organisms. Although rapid evolutionary response to temperature-mediated selection may allow local persistence of populations under global warming, and therefore is a key aspect of evolutionary biology, solid proof of its occurrence is rare. In this study, we tested for genetic adaptation to an increase in temperature in the water flea Daphnia magna, a keystone species in freshwater systems, by performing a thermal selection experiment under laboratory conditions followed by the quantification of microevolutionary responses to temperature for both life-history traits as well as for intraspecific competitive strength. After three months of selection, we found a microevolutionary response to temperature in performance, but only in one of two culling regimes, highlighting the importance of population dynamics in driving microevolutionary change within populations. Furthermore, there was an evolutionary increase in thermal plasticity in performance. The results of the competition experiment were in agreement with predictions based on performance as quantified in the life table experiment and illustrate that microevolution within a short time frame has the ability to influence the outcome of intraspecific competition.


Subject(s)
Acclimatization/genetics , Daphnia/genetics , Animals , Biological Evolution , Daphnia/physiology , Genotype , Greenhouse Effect , Population Dynamics , Selection, Genetic
18.
Psychiatr Pol ; 36(3): 421-34, 2002.
Article in Polish | MEDLINE | ID: mdl-12149918

ABSTRACT

Although, emotions play a crucial role in schizophrenia, the changes in emotional dimension in relation to brain asymmetry still remain controversial. The aim of our work was: 1) to compare the emotional behaviour between the examined groups: S--non-chronic schizophrenic patients (n = 50), CS--chronic schizophrenic patients (n = 50), N--healthy controls (n = 50), R--right brain-damaged patients (n = 30), and L--left brain-damaged patients (n = 30), 2) to assess the changes in attitude processes and in types of emotional reactions, its relation to lateralised hemisphere damage and chronicity of the schizophrenic process. All psychiatric subjects were diagnosed as paranoid schizophrenics according to DSM-IV criteria and were scored on the PANSS scale after four weeks of neuroleptic treatment. Brain-damaged patients were included if they experienced single-episode cerebrovascular accidents causing right or left hemisphere damage (confirmed in CT scan reports). The neurological patients were examined at least 3 weeks after the onset of the episode. Emotional behaviour was assessed using Observational Scale of Emotional Behaviour aimed at the evaluation of: A) attitude processes B) the emotional reactions. Our results revealed differentiated type of emotional behaviour in the examined population. Right brain-damaged patients significantly often revealed elevated mood, lack of adequacy of self-evaluation and active or negative attitude towards the environment. Left brain-damaged patients showed depressed mood, resignation, positive or seldom passive attitude to others and adequate self-evaluation. Schizophrenic patients mostly revealed indifferent mood and passive attitude to environment, their self-evaluation was rather adequate. Based on our data, the changes in emotional behaviour in schizophrenic patients might reflect frontal lobes dysfunction rather than dysfunction localised in one of cerebral hemispheres.


Subject(s)
Affective Symptoms/etiology , Brain Damage, Chronic/complications , Brain Ischemia/complications , Schizophrenia/complications , Schizophrenic Psychology , Adult , Affective Symptoms/psychology , Brain/blood supply , Brain Damage, Chronic/etiology , Brain Ischemia/diagnosis , Case-Control Studies , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Schizophrenia/pathology , Severity of Illness Index , Surveys and Questionnaires
19.
Psychiatr Pol ; 36(3): 435-48, 2002.
Article in Polish | MEDLINE | ID: mdl-12149919

ABSTRACT

Emotional behaviour in non-chronic and chronic schizophrenic patients, right and left hemisphere-damaged patients and healthy people was observed. Similar type of emotional reactions have been recorded in schizophrenia and right hemisphere damage. This might suggest the similarity of localisation of the cerebral dysfunction in the two patient groups. The difficulties with catching verbal expressions and verbal humour might be associated with the frontal cortex dysfunction.


Subject(s)
Brain Damage, Chronic/complications , Brain/pathology , Expressed Emotion , Schizophrenia/complications , Schizophrenic Psychology , Verbal Behavior , Adult , Behavior , Case-Control Studies , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Schizophrenia/pathology , Severity of Illness Index , Surveys and Questionnaires
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