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29362. The development of chloroplast ultrastructure and Hill reaction activity during leaf ontogeny in different maize (Zea mays L.) genotypes
- Creator:
- Kutík, J., Kočová, M., Holá, D., and Körnerová, M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chloroplast dimensions, electron microscopy, peripheral reticulum, photosynthesis, plastoglobuli, starch, stereology, stroma, and thylakoids
- Language:
- Multiple languages
- Description:
- Changes in Hill reaction activity (HRA) and ultrastructure of mesophyll cell (MC) chloroplasts were studied during the ontogeny of third leaf of maize plants using polarographic oxygen evolution measurement, transmission electron microscopy, and stereology. The chloroplast ultrastructure was compared in young (actively growing), mature, and senescing leaves of two different inbreds and their reciprocal F1 hybrids. Statistically significant differences in both HRA and MC chloroplast ultrastructure were observed between different stages of leaf ontogeny. Growth of plastoglobuli was the most striking characteristic of chloroplast maturation and senescence. The chloroplasts in mature and senescing leaves had a more developed system of thylakoids compared to the young leaves. Higher HRA was usually connected with higher thylakoid volume density of MC chloroplasts. and J. Kutík ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29363. The development of Myxobolus pavlovskii (Myxozoa: Myxobolidae) includes an echinactinomyxon-type actinospore
- Creator:
- Marton, Szilvia and Eszterbauer, Edit
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Myxosporea, life cycle, silver carp, Hypophthalmichthys molitrix, 18S rDNA, histology, and infection experiment
- Language:
- English
- Description:
- Echinactinomyxon-type actinospores were found in a mixed-species oligochaete culture originating from the Temperate Water Fish Hatchery near Budapest, Hungary. On the basis of DNA sequence analysis, the actinospores were identified as Myxobolus pavlovskii (Akhmerov, 1954), the 18S rDNA sequence from myxospores of which is available in GenBank. Silver carp Hypophthalmichthys molitrix (Valenciennes) fry specimens were successfully infected by cohabitation with the echinactinomyxon-releasing oligochaetes, which confirmed the molecular data congruence. The echinactinomyxons and the myxospores that developed in the gills of exposed fish fry were analysed morphologically and on DNA basis. The infected gill tissue was examined histologically. As typical characters of M. pavlovskii, numerous small plasmodia were observed in the epithelia of gill lamellae. Plasmodia contained thousands of myxospores with polar capsules unequal in size and with large intercapsular processes. The 18S rDNA sequence from actinospores and those from myxospores originating from the experimentally infected fish were identical. The oligochaete species releasing actinospores was morphologically determined as Limnodrilus sp. This is the first record of an echinactinomyxon as an alternate stage within the genus Myxobolus.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29364. The development of Procamalianus (Spirocamallanus) neocaballeroi (Nematoda: Camallanidae), a parasite of Astyanax fasciatus (Pisces) in Mexico
- Creator:
- Moravec, František and Vargas-Vázquez, Joaquin
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Nematoda, Procamalianus, Spirocamallanus, Astyanax, Copepoda, development, and Mexico
- Language:
- English
- Description:
- The development of the nematode Procamalianus (Spirocamallanus) neocaballeroi (Caballero-Deloya, 1977), an intestinal parasite of the characid fish, Astyanax fasciatus (Cuvier) in Mexico, was studied in the experimental copepod intermediate host, Mesocyclops sp. After the copepod’s ingestion of free first-stage larvae of the nematode, these penetrate into the haemocoel of the intermediate host; they moult twice (on the 3rd and 4-5th day p.i. at 21-22”C) before they attain the third, infective stage. The third-stage larva already possesses the large buccal capsule subdivided into an anterior broad portion with eight spiral thickenings (as observed in lateral view) and a narrow posterior portion, and its tail tip bears three conical processes. The definitive host acquires infection by feeding on infected copepods; in the intestine of this fish, the nematode larvae undergo two more moults (on the 10th and 14-15th day p.i. at 25-32°C) before attaining their maturity. The prepatent period is approximately two months.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29365. The development of the tegument in ontogenesis of Triaenophorus nodulosus (Cestoda: Pseudophyllidea)
- Creator:
- Davydov, V. G., Korneva, J. V., and Kuperman, B. I.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Pseudophyllidea, Triaenophorus, oncosphere, procercoid, plerocercoid, adult, fine structure, and tegument
- Language:
- English
- Description:
- The tegument ultrastructure of the cestode Triaenophorus nodulosus has been studied in the stages of oncosphere, procercoid, plerocercoid and adult. The syncytium of primary tegument has glandular origin and is located in the peripheral areas of the oncosphere. The primary tegument degenerates at the initial stages of the procercoid development and is replaced with secondary tegument persisting throughout all following stages of the worm’s development. Two ways of microthrix formation on the body surface of procercoid were discovered. The formation of the cyst consisting of fibrillar material around the plerocercoid was observed. It fills spaces between numerous finger-like évaginations of plerocercoid’s tegument. The structural differentiation of tegument and microtriches was demonstrated on the scolex and all parts of strabila of T. nodulosus.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29366. The developmental changes in mitochondrial DNA content per cell in human cord blood leukocytes during gestation
- Creator:
- Martina Hůlková, Markéta Tesařová, Tomáš Honzík, Hana Hansíková, Martin Magner, and Jiří Zeman
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, biochemie, genomika, DNA (nukleová kyselina), pupečník, biochemistry, genomics, deoxyribonucleic acid, umbilical cord, mitochondrial DNA, human cord blood leukocytes, real-time PCR, 14, and 612
- Language:
- English
- Description:
- The mitochondrial DNA (mtDNA) amount in cells as the basis for mitochondrial energy generating system, which produces ATP, plays an important role in the fetal development and postnatal morbidity. Isolated human cord blood leukocytes (HCBL) contribute very little to the overall metabolic turnover, but they may serve as easily available marker cells for the study of the mtDNA amount changes in cord blood during fetal development. The aim of our study was to analyze the mtDNA amount in HCBL. HCBL were isolated from cord blood samples of 107 neonates born between the 25th and 41st week of gestation. The mtDNA amount was analyzed by the real-time PCR method. The significant negative correlations were found between the relative mtDNA amount in HCBL and gestational age (r = -0.54, p<0.01) and birth weight (r = -0.43, p<0.01), respectively. The results revealed that the mtDNA content per cell decreases in HCBL with progressing fetal development. This may be explained by gradual shift of the hematopoiesis from fetal liver to bone marrow during the second half of pregnancy presumably accompanied by decreasing cell volume of HCBL as it was shown similarly in red blood cells., M. Pejznochová, M. Tesařová, T. Honzík, H. Hansíková, M. Magner, J. Zeman., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29367. The diagnosis of a personality disorder increases the likelihood for seropositivity to Toxoplasma gondii in psychiatric patients
- Creator:
- Hinze-Selch, Dunja, Däubener, Walter, Erdag, Sükran, and Wilms, Sibylle
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Toxoplasma gondii, personality disorder, major depression, schizophrenia, and serology
- Language:
- English
- Description:
- Individuals serologically positive for the chronic infection with the parasite Toxoplasma gondii (TG) display certain personality traits differently from uninfected individuals. Experimental data in mice demonstrate that TG infection modulates behaviour. However, psychiatric patients with a personality disorder have not yet been investigated systematically. In our sample containing 896 psychiatric inpatients with the primary diagnoses of schizophrenia, major depression, schizoaffective or bipolar disorder and 214 psychiatrically unaffected controls (same geographic region, sampled during same time period) we analysed for effects of the additional diagnosis of a personality disorder in the patients. Psychiatrically, a patient can meet the criteria of a personality disorder additionally to any of the mentioned primary diagnoses. We applied logistic regression and cross-table statistics, separated groups by the presence/absence of a personality disorder (ICD-10) and adjusted for age between groups. We found that among all patients the additional diagnosis of a personality disorder was significantly associated with TG infection. Furthermore, only in the patients with an additional personality disorder medium titre responses (1:16-1:64) were associated with chronic course and high C-reactive protein (CRP) levels whereas high titre response (>1:64) was associated with a more acute recurrent clinical course. In the older individuals only there was a preponderance of medium titre responses (1:16-1:64) among the patients with personality disorder compared to those without and controls. We conclude that TG infection and the host's response to it make a difference for the diagnosis of a personality disorder. Our data support that TG infection can modulate human behaviour and personality traits.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29368. The differential effect of photoinhibition on the quantum yield of oxygen evolution and on the electron transport capacity studied with isolated spinach thylakoids
- Creator:
- Richter, M., Bóthin, B., and Wild, A.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- The light response changes of oxygen evolutíon in the isolated spinách (Spinacia oleracea L.) thylakoids associated with the photoinhibition, influenced by the temperature and radical protection, were determined. Photoinhibition was performed at 20 ®C with or without an addition of antioxidant mixture consisting of glutathione, ascorbate, superoxide dismutase and catalase, oř, altematívely, at 0 oC without the antioxidants. Beside the effects on decline of atrazine binding sites and variable room temperature fluorescence, the three variants of photoinhibition differed with respect to their effects on the yield of oxygen evolutíon. Quantum yield of oxygen evolutíon (<{>02) flecline preceded Úie decrease of electron transport capacity at the beginning, while similar low values were found at the end of the treatment. In the presence of antioxidants the electron transport capacity remained high, whereas marked decline of (|»o^ occurred with the equally treated thylakoids. Comparable deviating behaviour of (t»Oj and the electron transport capacity was not found following photoinhibition at 0 oC; both were affected to the same degree, regardless if ferricyanide or the Qg- independent electron acceptor siUcomolybdate were ušed. With isolated thylakoids the quotient FyF,„, which is often ušed as a measure for photochemical efficiency of open photosystem 2 reaction centres in whole plant studies, did not decline to the same extent as (|)Oj under the dififerent photoinhibitoiy conditions applied. The main conclusion is that in thylakoid photoinhibition the independent mechanisms are associated with the changes of both the and electron transport capacity, and that the (j>02-related mechanism is inhibited at 0 oC.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29369. The difficult clinical diagnosis of erythropoietic protoporphyria
- Creator:
- Wahlin , S. , Floderus, Y., Ros, A-M., Broomé, U., and Harper, P.
- Type:
- article, model:article, and TEXT
- Subject:
- Erythropoietic protoporphyria (EPP), Diagnosis, Protoporphyrin, and Sunshine intolerance
- Language:
- English
- Description:
- We give a short survey of the Swedish erythropoietic protoporphyria patients (EPP) with respect to the lapsed time between symptom debut and diagnosis. With two examples we illustrate the consequence of undiagnosed EPP for the patient and also the family. We recall efforts to spread information among health workers in order to investigate patients suffering from extreme sun-exposure intolerance for this uncommon kind of porphyria as well.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29370. The dissident and the spectre: reading Havel with Derrida
- Creator:
- Björk, Ulrika
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Havel, Derrida, dissident, spectre, ideology, post-democracy, and messianism
- Language:
- Czech
- Description:
- In this paper I argue that there is an affinity between the ‘dissident’ in Havel’s essay “The Power of the Powerless” and the ‘spectre’ in Derrida’s readings of Marx. Both are manifestations of a specific modern temporality that Derrida calls “disjointed”, because it is haunted by a revolutionary force and claim for justice. Both also evoke the weak messianic power inherent in Walter Benjamin’s historiography and the spectral responsibility recognised by this power, that is, our responsibility for past and future generations. In post-totalitarian Czechoslovakia, the “nonpolitical” dissident community prefigured the renewal of moral experiences of responsibility and solidarity. In contemporary discussions of democracy, the figure of the spectre is a reminder of the significance of the Marxist legacy beyond its ideological doctrine.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public