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51.
Hao Jie Wong Nuradilla Mohamad-Fauzi Mohammed Rizman-Idid Peter Convey Jerzy Smykla Siti Aisyah Alias 《Environmental microbiology》2022,24(7):3164-3180
Solar radiation regulates most biological activities on Earth. Prolonged exposure to solar UV radiation can cause deleterious effects by inducing two major types of DNA damage, namely, cyclobutane pyrimidine dimers (CPDs) and pyrimidine 6-4 pyrimidone photoproducts. These lesions may be repaired by the photoreactivation (Phr) and nucleotide excision repair (NER) pathways; however, the principal UV-induced DNA repair pathway is not known in the fungal genus Pseudogymnoascus. In this study, we demonstrated that an unweighted UV-B dosage of 1.6 kJ m−2 d−1 significantly reduced fungal growth rates (by between 22% and 35%) and inhibited conidia production in a 10 d exposure. The comparison of two DNA repair conditions, light or dark, which respectively induced photoreactivation (Phr) and NER, showed that the UV-B-induced CPDs were repaired significantly more rapidly in light than in dark conditions. The expression levels of two DNA repair genes, RAD2 and PHR1 (encoding a protein in NER and Phr respectively), demonstrated that NER rather than Phr was primarily activated for repairing UV-B-induced DNA damage in these Pseudogymnoascus strains. In contrast, Phr was inhibited after exposure to UV-B radiation, suggesting that PHR1 may have other functional roles. We present the first study to examine the capability of the Arctic and Antarctic Pseudogymnoascus sp. to perform photoreactivation and/or NER via RT-qPCR approaches, and also clarify the effects of light on UV-B-induced DNA damage repair in vivo by quantifying cyclobutene pyrimidine dimers and pyrimidine 6-4 pyrimidone photoproducts. Physiological response data, including relative growth rate, pigmentation and conidia production in these Pseudogymnoascus isolates exposed to UV-B radiation are also presented. 相似文献
52.
Hardik Doshi Natalie Wiseman Jun Liu Wentao Wang Robert D. Welch Brian J. O’Neil Conor Zuk Xiao Wang Valerie Mika Jerzy P. Szaflarski E. Mark Haacke Zhifeng Kou 《PloS one》2015,10(2)
Mild traumatic brain injury (mTBI) is a significant public health care burden in the United States. However, we lack a detailed understanding of the pathophysiology following mTBI and its relation to symptoms and recovery. With advanced magnetic resonance imaging (MRI), we can investigate brain perfusion and oxygenation in regions known to be implicated in symptoms, including cortical gray matter and subcortical structures. In this study, we assessed 14 mTBI patients and 18 controls with susceptibility weighted imaging and mapping (SWIM) for blood oxygenation quantification. In addition to SWIM, 7 patients and 12 controls had cerebral perfusion measured with arterial spin labeling (ASL). We found increases in regional cerebral blood flow (CBF) in the left striatum, and in frontal and occipital lobes in patients as compared to controls (p = 0.01, 0.03, 0.03 respectively). We also found decreases in venous susceptibility, indicating increases in venous oxygenation, in the left thalamostriate vein and right basal vein of Rosenthal (p = 0.04 in both). mTBI patients had significantly lower delayed recall scores on the standardized assessment of concussion, but neither susceptibility nor CBF measures were found to correlate with symptoms as assessed by neuropsychological testing. The increased CBF combined with increased venous oxygenation suggests an increase in cerebral blood flow that exceeds the oxygen demand of the tissue, in contrast to the regional hypoxia seen in more severe TBI. This may represent a neuroprotective response following mTBI, which warrants further investigation. 相似文献
53.
Wies?awa Klimek-Piotrowska Mateusz Koziej Mateusz K. Ho?da Katarzyna Pi?tek Karolina Wszo?ek Anna Tyszka Elizabeth Kmiotek Mateusz Pliczko Aleksandra ?liwińska Klaudia Krauss Marcin Miszczyk Jerzy Walocha 《PloS one》2015,10(3)
Background and Objective
The aim of the present study was to determine the level of adiposity and obesity in Polish adolescents and compare the results with earlier studies conducted in this population as well as those carried out in other populations.Methods
The study group consisted of 456 boys and 514 girls aged 14-18 years living in Cracow chosen from randomly selected secondary schools. Weight, height, waist, and hip circumference (WC, HC) as well as triceps, biceps, subscapular, and suprailiac skinfold thickness (SFT) were measured. Body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), subscapular/triceps skinfold ratio (STR), and percentage body fat were computed. The prevalence of overweight and obesity based on Polish children growth reference were calculated and age-dependent and gender-specific smoothed percentile curves for BMI and ROC curves were generated.Results
Weight, height, WC, HC (up 16yr), WHtR (up 15yr), and WHR were considerably higher in males than females. Weight, height, and HC increased with age; WHtR remained the same. The prevalence of overweight and obesity were 10.2% (boys 10.3%; girls 10.1%) and 4.2% (boys 5.3%; girls 3.3%). ROC analysis revealed that WHtR was the best tool for detection of obesity (AUC of 0.982±0.007) in males, whereas the sum of four SFTs (AUC: 0.968±0.011) and WHtR (AUC: 0.963±0.012) were the best predictors of obesity in females.Conclusions
The level of adiposity in Cracow adolescents increased during the last decade. However, it is still lower than in other well-developed societies struggling with obesity epidemics. 相似文献54.
Facilitative and antagonistic interactions between plant viruses in mixed infections 总被引:3,自引:0,他引:3
Syller J 《Molecular Plant Pathology》2012,13(2):204-216
Mixed infections of plant viruses are common in nature, and a number of important virus diseases of plants are the outcomes of interactions between causative agents. Multiple infections lead to a variety of intrahost virus-virus interactions, many of which may result in the generation of variants showing novel genetic features, and thus change the genetic structure of the viral population. Hence, virus-virus interactions in plants may be of crucial significance for the understanding of viral pathogenesis and evolution, and consequently for the development of efficient and stable control strategies. The interactions between plant viruses in mixed infections are generally categorized as synergistic or antagonistic. Moreover, mixtures of synergistic and antagonistic interactions, creating usually unpredictable biological and epidemiological consequences, are likely to occur in plants. The mechanisms of some of these are still unknown. This review aims to bring together the current knowledge on the most commonly occurring facilitative and antagonistic interactions between related or unrelated viruses infecting the same host plant. The best characterized implications of these interactions for virus-vector-host relationships are included. The terms 'synergism' and 'helper dependence' for facilitative virus-virus interactions, and 'cross-protection' and 'mutual exclusion' for antagonistic interactions, are applied in this article. 相似文献
55.
A series of 5-substituted derivatives of the potent phenylalanine ammonia-lyase (PAL) inhibitor 2-aminoindane-2-phosphonic acid (AIP; 2) were synthesized. The AIP analogues 3-7, with additional NO2, NH2, Me, Br, and OH groups, respectively, were tested as in vitro inhibitors of buckwheat PAL, and as in vivo inhibitors of anthocyanin biosynthesis. Within this series, the racemic 5-bromo (6) and 5-methyl (7) congeners were biologically most active (Table), although being ca. one order of magnitude less potent than AIP proper. 相似文献
56.
57.
Warmuz-Stangierska I Czarnywojtek A Ziemnicka K Gryczyńska M Stangierski R Sowiński J 《Endokrynologia Polska》2006,57(6):619-623
INTRODUCTION: The aim of study was the evaluation of association between psychometric factors in patients with thyroid cancer and in Graves' hyperthyroid patients. MATERIAL AND METHODS: We examined 50 patients with differentiated thyroid cancer, 42 females (84.75%), 8 males aged from 32 to 64 yr. (x +/- SD: 43 +/- 8.17 yr.) and 50 hyperthyroid patients, 45 (90%) females and 5 (10%) males corresponding aged. We used the following methods: the EAS Temperament Survey (EASD) in addition for adults, EPQ Eysenck Personality Questionnaire, Polish Abbreviated Form of the MMPI (DKO-74) and Beck's Depression Scale. We compared the scores of thyroid cancer patients and hyperthyroid patients. RESULTS: We have interpreted obtained results in both groups as similarly in: mild sense depression, high emotional control, high social dependence, ambiverssion, mild level of emotional mental balance. CONCLUSION: Results of our explorations appears great psychological similarity between differentiated thyroid patients and hyperthyroid patients. 相似文献
58.
59.
Kołodziej Barbara Kochan Ewa Kazimierczak Jerzy Chmiel Aleksander 《Plant Growth Regulation》2006,48(1):13-19
American ginseng (Panax quinquefolium L.) is a perennial medicinal herb originally grown in Canada and USA, and recently also in China, Australia, Holland and
Poland. Several commercial preparations are produced from ginseng roots, that are known for their antifatigue, antitumor,
antistress and immune system stimulating functions. The medicinal properties are due mainly to the active components – ginsenosides.
In this work, the results of field cultivation experiments are presented that examine the effects of foliar application of
several growth regulators on quality parameters and ginsenoside content of P. quinuefolium roots. The growth regulators tested, i.e., kinetin, daminozide, mixture of gibberellic acid (GA3) with potassium salt of α-naphthalene acetic acid (kNAA) and new preparation – IPO-1 – benzimidazole derivative (obtained
from the Institute of Organic Industry in Warsaw – at present during the process of patent), were applied at a concentration
of 100 or 200 mg l−1 in the middle of June in the 2nd year of vegetation. After 4 years of cultivation, the roots were dug up and dried, and subsequently
the quantitative analysis of individual saponins (Rb1, Rb2, Rc, Rd, Re, Rg1) by HPLC was performed. Growth regulators significantly affected quality parameters, morphological features and accumulation
of individual and total ginsenosides in ginseng roots. Regardless of doses, the plant roots treated with growth regulators
had a higher content of total ginsenosides in comparison to the control. The growth regulators also affected individual ginsenosides
level and narrowed the ratio of Rb:Rg group. The application of kinetin, daminozide and benzimidazole derivative for foliar spray during 2nd year of American ginseng
vegetation caused a significant increase in air dry weight of roots and aboveground parts whereas the mixture of GA3 and kNAA showed a decreasing effect. An increase of roots size was observed using higher doses (200 mg l−1) of kinetin and daminozide while a decreasing tendency appeared with the application of the other preparations. 相似文献
60.
Jerzy K. Kulski Silvana Gaudieri Matthew Bellgard Lois Balmer Keith Giles Hidetoshi Inoko Roger L. Dawkins 《Journal of molecular evolution》1997,45(6):599-609
Sequence analysis of a 237 kb genomic fragment from the central region of the MHC has revealed that the HLA-B and HLA-C genes
are contained within duplicated segments peri-B (53 kb) and peri-C (48 kb), respectively, and separated by an intervening
sequence (IF) of 30 kb. The peri-B and peri-C segments share at least 90% sequence homology except when interrupted by insertions/deletions
including Alu, L1, an endogenous retrovirus, and pseudogenes. The sequences of peri-B, IF, and peri-C were searched for the
presence of Alu elements to use as markers of evolution, chromosomal rearrangements, and polymorphism. Of 29 Alu elements,
14 were identified in peri-B, 11 in peri-C, and 4 in IF. The Alu elements in peri-B and peri-C clustered phylogenetically
into two clades which were classified as ``preduplication' and ``postduplication' clades. Four Alu J elements that are shared
by peri-B and peri-C and are flanked by homologous sequences in their paralogous locations, respectively, clustered into a
``preduplication' clade. By contrast, the majority of Alu elements, which are unique to either peri-B or peri-C, clustered
into a postduplication clade together with the Alu consensus subfamily members ranging from platyrrhine-specific (Spqxcg)
to catarrhine-specific Alu sequences (Y). The insertion of platyrrhine-specific Alu elements in postduplication locations
of peri-B and peri-C implies that these two segments are the products of a duplication which occurred in primates prior to
the divergence of the New World primate from the human lineage (35–44 mya). Examination of the paralogous Alu integration
sites revealed that 9 of 14 postduplication Alu sequences have produced microsatellites of different length and sequence within
the Alu 3′-poly A tail. The present analysis supports the hypothesis that HLA-B and HLA-C genes are products of an extended
segmental duplication between 44 and 81 million years ago (mya), and that subsequent diversification of both genomic segments
occurred because of the mobility and mutation of retroelements such as Alu repeats.
Received: 21 May 1997 / Accepted: 9 July 1997 相似文献