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131.
The sub-cellular feruloylation and oxidative coupling sites of cell wall polysaccharides were investigated in planta by monitoring
the kinetics of appearance of arabinosyl- and feruloyl-radiolabelled polysaccharides in the protoplasmic compartment and their
secretion in the wall either in the presence or absence of brefeldin A (BFA). By using root apical segments excised from wheat
seedlings (Triticum durum Desf.), incubated with trans-[U-14C]cinnamic acid, we demonstrated that [14C]ferulate, likely [14C]diferulate, as well as trimers and larger products of ferulate are incorporated into the protoplasmic polysaccharides very
rapidly within 1–3 min of [14C]cinnamate feeding. This agrees with the assumption that (glucurono)arabinoxylans [(G)AX] feruloylation and oxidative coupling
occur intracellularly, likely in the Golgi apparatus. Simultaneously, polymer bound radioactive hydroxycinnamic acids appeared
to be incorporated into the cell wall of root apical segments as early as 2 min after trans-[U-14C]cinnamic acid feeding. On the contrary, starting from l-[1-14C]arabinose as tracer, the secretion of the pentose-containing polymers into the wall was between 5 to 10 min. These results
indicated that (G)AX feruloylation and oxidative coupling occur both intra-protoplasmically and in muro. The occurrence of
in muro feruloylation and oxidative coupling was confirmed by the use of BFA a well known inhibitor of secretion. The drug
caused a strong inhibition of the synthesis and secretion into the wall of the 14C-pentosyl-labelled polymers as well as of 14C-feruloyl-polymers. In spite of this, the total amount of 14C-feruloyl-polymers incorporated into the wall was only slightly affected by BFA. This indicates the existence of a mechanism
involved into secretion of the activated hydroxycinnamoyl precursors to the wall, alternative to that involved in polysaccharide
secretion.
Lucia Ilenia Mastrangelo and Marcello Salvatore Lenucci equally contributed to this work. 相似文献
132.
A radioimmunossay (RIA) for the measurement of both unconjugated and total serum estetrol has been developed, using an antiserum to an E4-3-conjugate and a 125I-radioiodinated E4 tracer. Assay of dried ethyl ether extracts was used for the determination of unconjugated E4, while a direct measurement of unextracted hydrolyzed serum in the presence of 0.3% 8-anilino-1-naphthalene sulphonic acid (ANS) proved adequate for total E4. Assay reliability was evaluated and the procedure standardized through a series of tests aimed at assessing accuracy, sensitivity and precision. No steroidal interference was found to practically affect the assay (0.3% estriol cross-reactivity), nor were solvent and sample blanks observed in the case of unconjugated E4. For total E4 assay, the sample blank effects were acceptably overcome by using hydrolyzed male serum and 0.3% ANS, as a standard diluent. An interassay variability amounting to approximately 10 and 6% resulted for unconjugated E4 and total E4 RIA, respectively. A number of serum samples (285 for unconjugated E4, 147 for total E4) randomly collected throughout normal pregnancy were assayed. The unconjugated E4 levels at 15th week and at term were 62.7 +/- 22.6 and 766.5 +/- 208.2 (SD) pg/ml, respectively. Total E4 was about 6--7 times higher than the levels of free E4 and increased 7 times from the 15th week to term. 相似文献
133.
Maria Cristina Piro Alessandra Gambacurta Franca Ascoli 《Journal of molecular evolution》1996,43(6):594-601
A and B globin cDNAs from the tetrameric hemoglobin of the bivalve molluscScapharca inaequivalvis were isolated by RT-PCR and sequenced. When compared with the biochemical data, the deduced protein sequences revealed only one amino acid substitution in the B chain. In order to investigate the genomic structure of these invertebrate globin genes, their intronic regions were amplified by PCR. The two genes showed the typical two-intron/three-exon organization found in vertebrates and seemed to reflect the ancestral gene structure, in accordance with the new globin gene evolution theory proposed by Dixon and Pohajadak (Trends Biochem. Sci. 17:486–488, 1992). The alternative hypothesis suggested by Go (Nature 291:90–92, 1981), that the central intron was lost during evolution, is also considered. In contrast to the related clamAnadara trapezia, S. inaequivalvis A and B globin genes were found to be present in multiple copies differing in intron size. In this study we report the complete sequences of the A (1,471 bp) and B (2,221 bp) globin genes, giving a detailed analysis of their intron features. 相似文献
134.
S Andò C Giacchetto M Canonaco S Aquila A Valenti E Beraldi A Piro F Dessì-Fulgheri 《Hormone research》1986,23(2):122-127
In the present study we investigated the effects of castration on androstenedione (A), testosterone (T) and dihydrotestosterone (DHT) plasma levels in adult male rats 5 and 47 days after castration. In another group of 60-day-old castrated rats, the three steroids have been evaluated during testosterone propionate administration. Our data show that 5 days after orchiectomy all three steroids were significantly decreased (p less than 0.001) with respect to control values. 47 days after orchiectomy, T and DHT were also significantly decreased with respect to the control group. In both groups of orchiectomized rats the A/T ratio increased significantly with respect to controls. On the contrary, the T/DHT ratio sharply decreased. This suggests that DHT, in orchiectomized rats, could derive from precursors other than T. A negative correlation between A and the T/DHT ratio was observed 47 days after castration in adult animals and emphasized upon testosterone propionate administration. In the latter group, T was significantly lower while A is significantly augmented with respect to control values. Finally, the above-mentioned negative correlation indicates a possible prevalent role of A in contributing to the circulating levels of DHT in adult orchiectomized rats. 相似文献
135.
HeinzR. Khler Yvan Capowiez Christophe Mazzia Helene Eckstein Nils Kaczmarek Mark C. Bilton Janne K. Y. Burmester Line Capowiez Luis J. Chueca Leonardo Favilli Josep Florit Gomila Giuseppe Manganelli Silvia Mazzuca Gregorio MorenoRueda Katharina Peschke Amalia Piro Josep Quintana Cardona Lilith Sawallich Alexandra E. Staikou Henri A. Thomassen Rita Triebskorn 《Ecology and evolution》2021,11(3):1111
In terrestrial snails, thermal selection acts on shell coloration. However, the biological relevance of small differences in the intensity of shell pigmentation and the associated thermodynamic, physiological, and evolutionary consequences for snail diversity within the course of environmental warming are still insufficiently understood. To relate temperature‐driven internal heating, protein and membrane integrity impairment, escape behavior, place of residence selection, water loss, and mortality, we used experimentally warmed open‐top chambers and field observations with a total of >11,000 naturally or experimentally colored individuals of the highly polymorphic species Theba pisana (O.F. MÜller, 1774). We show that solar radiation in their natural Mediterranean habitat in Southern France poses intensifying thermal stress on increasingly pigmented snails that cannot be compensated for by behavioral responses. Individuals of all morphs acted neither jointly nor actively competed in climbing behavior, but acted similarly regardless of neighbor pigmentation intensity. Consequently, dark morphs progressively suffered from high internal temperatures, oxidative stress, and a breakdown of the chaperone system. Concomitant with increasing water loss, mortality increased with more intense pigmentation under simulated global warming conditions. In parallel with an increase in mean ambient temperature of 1.34°C over the past 30 years, the mortality rate of pigmented individuals in the field is, currently, about 50% higher than that of white morphs. A further increase of 1.12°C, as experimentally simulated in our study, would elevate this rate by another 26%. For 34 T. pisana populations from locations that are up to 2.7°C warmer than our experimental site, we show that both the frequency of pigmented morphs and overall pigmentation intensity decrease with an increase in average summer temperatures. We therefore predict a continuing strong decline in the frequency of pigmented morphs and a decrease in overall pigmentation intensity with ongoing global change in areas with strong solar radiation. 相似文献
136.
Insulin radioimmunoassay: a comparison of three methods 总被引:1,自引:0,他引:1
137.
A. Piro S. Mazzuca S. Phandee M. Jenke P. Buapet 《Plant biology (Stuttgart, Germany)》2023,25(3):420-432
- Mangrove seedlings are subject to natural tidal inundation, while occasional flooding may lead to complete submergence. Complete submergence reduces light availability and limits gas exchange, affecting several plant metabolic processes. The present study focuses on Rhizophora mucronata, a common mangrove species found along the coasts of Thailand and the Malay Peninsula.
- To reveal response mechanisms of R. mucronata seedlings to submergence, a physiological investigation coupled with proteomic analyses of leaf and root tissues was carried out in plants subjected to 20 days of control (drained) or submerged conditions.
- Submerged seedlings showed decreased photosynthetic activity, lower stomatal conductance, higher total antioxidant capacity in leaves and higher lipid peroxidation in roots than control plants. At the same time, tissue nutrient ion content displayed organ-specific responses. Proteome analysis revealed a significant change in 240 proteins in the leaves and 212 proteins in the roots. In leaves, most differentially accumulated proteins (DAPs) are associated with nucleic acids, stress response, protein transport, signal transduction, development and photosynthesis. In roots, most DAPs are associated with protein metabolic process, response to abiotic stimulus, nucleic acid metabolism and transport.
- Our study provides a comprehensive understanding of submergence responses in R. mucronata seedlings. The results suggest that submergence induced multifaceted stresses related to light limitation, oxidative stress and osmotic stress, but the responses are organ specific. The results revealed many candidate proteins which may be essential for survival of R. mucronata under prolonged submergence.
138.
139.
A. Tagarelli A. Piro S. Tagarelli G. Tagarelli 《International Journal of Anthropology》2000,15(3-4):241-253
Cholera, as it was regarding each infective disease of which nobody knew its aetiologic agent or, in any way, if its agent
was present really, was for the Calabrian people an unknown enemy that nobody knew anything about either its behaviour or
the modality of its penetration into the human body. During many years characterized by a medical methodological obscurantism,
Calabrian people lived, during the different choleric epidemics, on a daily life based upon the ignorance, and the pseudo-treatments,
and pseudo-physicians. During the cholera epidemics, not only the people groped in the dark, but also the governmental authorities
were confused because were subdivided into those who supported the theory of the epidemics spread and those who supported
the theory of the contagion spread. It must be emphasized that from the XX century, when the pathologies due to natural agents
were reduced and were substituted with those due to humans, cholera influenced very much the demography and the social-cultural
features of the Southern Italy. 相似文献