bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunohistochemical study on expression of α‐defensin and β‐defensin‐2 in human buccal epithelia with candidiasis
Authors: Sawaki K , Mizukawa N , Yamaai T , Fukunaga J , Sugahara T 
Published: March 2003

OBJECTIVES AND DESIGN: It has been previously reported that α‐defensin (HNPs) and β‐defensin‐2 (HBD‐2) peptides with antifungal and cytotoxic activities can be detected in oral carcinomas and the saliva of patients with oral carcinomas. The present study investigated the presence of HNPs and HBD‐2 in oral epithelia with candidiasis.MATERIALS AND METHODS: Tissue sections (4 μm) were prepared from biopsy and surgically removed specimens diagnosed as oral candidiasis (n=10). The sections were examined immunohistochemically with antibodies directed against HNPs and HBD‐2.RESULTS: Tissue sections of oral candidiasis were immunostained with antidefensin antibodies. Neutrophils in the inflamed lamina propria were positively immunostained with anti‐HNPs antibody. The cytoplasm of cells in the upper spinous layer, in the lower spinous layer and in the parakeratinized layer of buccal epithelia with candidiasis was immunostained intensely with anti‐HBD‐2 antibody. In contrast, the expression of HBD‐2 in the normal spinous layer was much weaker than that in oral candidiasis. No signals of HNPs were found in normal buccal epithelium.CONCLUSION: Buccal specimens from individuals with oral candidiasis show greater levels of expression of both HNPs and HBD‐2. There might be a dual protection manner by defensins against fungal inflammation in infected buccal epithelia locally. Generally, HBD‐2 signals have been found everywhere in the buccal epithelium; however, in an infected area, the signal intensity of HBD‐2 has increased. HNPs signals have not been found in the normal buccal epithelium; however, HNPs signals have increased when the infection occurred.
Cytokeratins in epithelia of odontogenic neoplasms
Authors: Crivelini MM , De Araújo VC , De Sousa SOM , De Araújo NS 
Published: March 2003

Neoplasms and tumours related to the odontogenic apparatus may be composed only of epithelial tissue or epithelial tissue associated with odontogenic ectomesenchyme. The immunohistochemical detection of different cytokeratins (CKs) polypeptides and vimentin has made it easier to explain the histogenesis of many epithelial diseases. The present study aimed to describe the immunohistochemical expression of cytokeratins 7, 8, 10, 13, 14, 18, 19 and vimentin in the epithelial components of the dental germ and of five types of odontogenic tumours. The results were compared and histogenesis discussed.All cells of the dental germ were positive for CK14, except for the preameloblasts and secreting ameloblasts, in which CK14 was gradually replaced by CK19. CK7 was especially expressed in the cells of the Hertwig root sheath and the stellate reticulum. The dental lamina was the only structure to express CK13. The reduced epithelium of the enamel organ contained CK14 and occasionally CK13. Cells similar to the stellate reticulum, present in the ameloblastoma and in the ameloblastic fibroma, were positive for CK13, which indicates a nature other than that of the stellate reticulum of the normal dental germ. The expression of CK14 and the ultrastructural aspects of the adenomatoid odontogenic tumour probably indicated its origin in the reduced dental epithelium. Calcifying odontogenic epithelial tumour is thought to be composed of primordial cells due to the expression of vimentin. Odontomas exhibited an immunohistochemical profile similar to that of the dental germ. In conclusion, the typical IF of odontogenic epithelium was CK14, while CK8, 10 and 18 were absent. Cytokeratins 13 and 19 labelled squamous differentiation or epithelial cells near the surface epithelium, and CK7 had variable expression.
Sexually Dimorphic Activation of Galanin Neurones in the Ferret's Dorsomedial Preoptic Area/Anterior Hypothalamus after Mating
Authors: Bakker J. , Woodley S. K. , Kelliher K. R. , Baum M. J. 
Published: March 2003

AbstractMale ferrets in breeding condition possess three times as many galanin‐immunoreactive (IR) neurones as oestrous females in the sexually dimorphic dorsomedial preoptic area/anterior hypothalamus (dmPOA/AH). Using Fos‐IR as a marker of activation, we investigated whether mating with intromission differentially activates this sexually dimorphic group of galanin‐IR neurones in male and female ferrets. Male ferrets that intromitted had a significantly greater percentage of galanin‐IR neurones in the dmPOA/AH that were colabelled with nuclear Fos‐IR than oestrous females that received an intromission. Intromissive stimulation augmented Fos‐IR in an equal percentage of galanin‐IR neurones in both sexes in the medial amygdala (MA) and bed nucleus of the stria terminalis (BNST). Peripheral anosmia induced by bilateral occlusion of males' nares did not reduce the mating‐induced activation of galanin‐IR neurones in the dmPOA/AH, and there was a significant correlation among individual males between intromission duration and the percentage of dmPOA/AH galanin‐IR neurones colabelled with Fos‐IR. Exposure of castrated, testosterone propionate‐treated male ferrets to either soiled bedding or to volatile odours from oestrous females failed to induce nuclear Fos‐IR in galanin‐IR neurones located in the dmPOA/AH, BNST or MA, suggesting that the mating‐induced activation of galanin‐IR forebrain neurones in male ferrets depends more on genital‐somatosensory than on olfactory inputs. The observed sex dimorphism in the mating‐induced activation of galanin‐IR neurones in the dmPOA/AH raises the possibility that these neurones perform a mating‐dependent function that occurs only in males.
Vulnerability to cavitation of leaf minor veins: any impact on leaf gas exchange?
Authors: Salleo S. , Lo Gullo M. A. , Raimondo F. , Nardini A. 
Published: March 2003

AbstractVulnerability to cavitation of leaf minor veins and stems of Laurus nobilis L. was quantified together with that of leaflets, rachides and stems of Ceratonia siliqua L. during air‐dehydration of 3‐year‐old branches. Embolism was estimated by counting ultrasound acoustic emissions (UAE) and relating them to leaf water potential (ΨL). The threshold ΨL for cavitation was less negative in L. nobilis than in C. siliqua according to the known higher drought resistance of the latter species. Leaf minor vein cavitation was also quantified by infiltrating leaves with fluorescein at different dehydration levels and observing them under microscope. Distinct decreases in the functional integrity of minor veins were observed during leaf dehydration, with high correlation between the two variables. The relationship between leaf conductance to water vapour (gL) and ΨL showed that stomata of L. nobilis closed in response to stem and not to leaf cavitation. However, in C. siliqua, gL decreased in coincidence to the leaf cavitation threshold, which was, nevertheless, very close to that of the stem. The hypothesis that stem cavitation acts as a signal for stomatal closure was confirmed, while the same role for leaf cavitation remains an open problem.
Molecular and biochemical responses of perennial forage crops to oxygen deprivation at low temperature
Authors: Bertrand A. , Castonguay Y. , Nadeau P. , Laberge S. , Rochette P. , Michaud R. , Bélanger G. , Benmoussa M. 
Published: March 2003

AbstractAnaerobic conditions developing under ice cover affect winter survival and spring regrowth of economically important perennial crops. Our objective was to assess interspecific differences in the resistance to anaerobic conditions at low temperature, and to relate those differences to plant metabolism. Four perennial forage species, alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.), timothy (Phleum pratense L.) and orchardgrass (Dactylis glomerata L.), were subjected to a progressively developing anoxic stress by enclosing potted plants in gas‐tight bags in late autumn and exposing them to simulated winter conditions in an unheated greenhouse. Near‐anaerobic conditions were reached after 60 d of enclosure for orchardgrass, alfalfa and red clover, and after 80 d for timothy. The sensitivity of the species to anaerobic conditions, based on plant regrowth, was: red clover and orchardgrass > alfalfa > timothy. The concentration of ethanol increased in response to oxygen deprivation, and reached the highest value in the sensitive red clover, whereas its concentration was the lowest in timothy. The expression of the alcohol dehydrogenase (ADH) gene was markedly lower in timothy than in the other three species for which the expression was equivalent. We conclude that the greater resistance of timothy to anaerobic conditions at low temperature is associated with a slower glycolytic metabolism.
Acclimation of tropical tree seedlings to excessive light in simulated tree‐fall gaps
Authors: Krause G. H. , Koroleva O. Y. , Dalling J. W. , Winter K. 
Published: March 2003

AbstractAcclimation to periodic high‐light stress was studied in tree seedlings from a neotropical forest. Seedlings of several pioneer and late‐succession species were cultivated under simulated tree‐fall gap conditions; they were placed under frames covered with shade cloth with apertures of different widths that permitted defined periods of daily leaf exposure to direct sunlight. During direct sun exposure, all plants exhibited a marked reversible decline in potential photosystem II (PSII) efficiency, determined by means of the ratio of variable to maximum Chl a fluorescence (Fv/Fm). The decline in Fv/Fm under full sunlight was much stronger in late‐succession than in pioneer species. For each gap size, all species exhibited a similar degree of de‐epoxidation of violaxanthin in direct sunlight and similar pool sizes of xanthophyll cycle pigments. Pool sizes increased with increasing gap size. Pioneer plants possessed high levels of β‐carotene that also increased with gap size, whereas α‐carotene decreased. In contrast to late‐succession plants, pioneer plants were capable of adjusting their Chl a/b ratio to a high value in wide gaps. The content of extractable UV‐B‐absorbing compounds was highest in the plants acclimated to large gaps and did not depend on the successional status of the plants. The results demonstrate a better performance of pioneer species under high‐light conditions as compared with late‐succession plants, manifested by reduced photoinhibition of PSII in pioneer species. This was not related to increased pool size and turnover of xanthophyll cycle pigments, nor to higher contents of UV‐B‐absorbing substances. High β‐carotene levels and increased Chl a/b ratios, i.e. reduced size of the Chl a and b binding antennae, may contribute to photoprotection in pioneer species.
Ultrastructural and immunohistochemical study of the basal apparatus of solitary cilia in the human oviduct epithelium
Authors: Hagiwara Haruo , Harada Shinsuke , Maeda Sakae , Aoki Takeo , Ohwada Nobuo , Takata Kuniaki 
Published: March 2003

AbstractThe basal apparatus of the solitary cilium is composed of the basal body, an associated centriole and the basal body‐associated structures. To see the connection between the basal body and the centriole, we studied the basal apparatus of solitary cilia in human oviductal secretory cells by electron microscopy and immunohistochemistry. A single centriole was present in the vicinity of the basal body of a solitary cilium. The basal body and the single centriole were interconnected by one or two bundles of thin filaments with a few periodic striations. We have called these bundles the striated connector. The periodicity of striations in the striated connector measured 55 ± 6 nm, about 15 nm shorter than that of striated rootlets. The striated connector was immunolabelled with R67 antibody specific to striated rootlets, indicating that they are composed of common molecule(s). Although the true function of the connector is unknown as yet, it could play an important role for stabilising the basal body in the apical cytoplasm.
Modelling the masticatory biomechanics of a pig
Authors: Langenbach G. E. J. , Zhang F. , Herring S. W. , Hannam A. G. 
Published: March 2003

AbstractThe relationships between muscle tensions, jaw motions, bite and joint forces, and craniofacial morphology are not fully understood. Three‐dimensional (3‐D) computer models are able to combine anatomical and functional data to examine these complex relationships. In this paper we describe the construction of a 3‐D dynamic model using the anatomical (skeletal and muscle form) and the functional (muscle activation patterns) features of an individual pig. It is hypothesized that the model would produce functional jaw movements similar to those recordable in vivo. Anatomical data were obtained by CT scanning (skeletal elements) and MR imaging (muscles). Functional data (muscle activities) of the same animal were obtained during chewing by bipolar intramuscular electrodes in six masticatory muscles and combined with previously published EMG data. The model was driven by the functional data to predict the jaw motions and forces within the masticatory system. The study showed that it is feasible to reconstruct the complex 3‐D gross anatomy of an individual's masticatory system in vivo. Anatomical data derived from the 3‐D reconstructions were in agreement with published standards. The model produced jaw motions, alternating in chewing side, typical for the pig. The amplitude of the jaw excursions and the timing of the different phases within the chewing cycle were also in agreement with previously published data. Condylar motions and forces were within expected ranges. The study indicates that key parameters of the pig's chewing cycle can be simulated by combining general biomechanical principles, individual‐specific data and a dynamic modelling approach frequently used in mechanical engineering.
Gender difference in benefits of twinning in pre‐industrial humans: boys did not pay
Authors: Lummaa Virpi , Jokela Jukka , Haukioja Erkki 
Published: March 2003

Summary

We studied how differences in the cost of producing male and female offspring in humans affected the productivity of twin vs. singleton deliveries in two ecologically different areas of pre‐industrial (1752–1850) Finland. Given the higher energy requirements of male infants, we predicted sons to suffer more from increased litter size and food scarcity than daughters.
We found that the number of offspring surviving to adulthood from a twin delivery differed between the archipelago and mainland areas of rural Finland. On the mainland areas, where crop failures and subsequent famines were common throughout the centuries, twin deliveries were much less successful than in the south‐west archipelago, where food conditions were traditionally more stable and survival was ensured by fishing.
Productivity of twin deliveries was modified by the gender composition of the twins; female–female twin births were generally most successful and male–male births least successful.
On the mainland, giving birth to twins of any gender composition never increased the mothers’ reproductive success beyond giving birth to either a male or female singleton, whereas in the archipelago mothers could increase their reproductive output by producing twins. This was because in the archipelago female–female twin deliveries contributed on average more than one adult offspring to the breeding population, whereas a singleton delivery of either gender produced only about 0·7 adults.
Our results show that increases in litter size and variability of food conditions increased male mortality. High female twin survival in the archipelago led to higher fitness of twinning mothers in relation to mothers with only singletons. Twinning has traditionally been significantly more common in the archipelago as compared to the mainland, but contrary to the prediction, there were no apparent differences in the frequency of male–male and female–female twins being born.
Effect of land cover, habitat fragmentation and ant colonies on the distribution and abundance of shrews in southern California
Authors: Laakkonen Juha , Fisher Robert N. , Case Ted J. 
Published: March 2003

Summary

Because effects of habitat fragmentation and anthropogenic disturbance on native animals have been relatively little studied in arid areas and in insectivores, we investigated the roles of different land covers, habitat fragmentation and ant colonies on the distribution and abundance of shrews, Notiosorex crawfordi and Sorex ornatus, in southern California.
Notiosorex crawfordi was the numerically dominant species (trap‐success rate 0·52) occurring in 21 of the 22 study sites in 85% of the 286 pitfall arrays used in this study. Sorex ornatus was captured in 14 of the sites, in 52% of the arrays with a total trap‐success rate of 0·2. Neither of the species was found in one of the sites.
The population dynamics of the two shrew species were relatively synchronous during the 4–5‐year study; the peak densities usually occurred during the spring. Precipitation had a significant positive effect, and maximum temperature a significant negative effect on the trap‐success rate of S. ornatus.
Occurrence and abundance of shrews varied significantly between sites and years but the size of the landscape or the study site had no effect on the abundance of shrews. The amount of urban edge had no significant effect on the captures of shrews but increased edge allows invasion of the Argentine ants, which had a highly significant negative impact on the abundance of N. crawfordi.
At the trap array level, the percentage of coastal sage scrub flora had a significant positive, and the percentage of other flora had a significant negative effect on the abundance of N. crawfordi. The mean canopy height and the abundance of N. crawfordi had a significant positive effect on the occurrence of S. ornatus.
Our study suggests that the loss of native coastal sage scrub flora and increasing presence of Argentine ant colonies may significantly effect the distribution and abundance of N. crawfordi. The very low overall population densities of both shrew species in most study sites make both species susceptible to extinction in isolated habitat fragments due to environmental stochasticity, and anthropogenic disturbance.
Canopy and substratum heterogeneity influence recruitment of the mangrove Avicennia marina
Authors: Minchinton Todd E. 
Published: March 2003

Summary

Mangrove forests are structurally complex with canopy gaps generated by physical disturbances such as storms and mounds created on the forest floor by biotic disturbances such as crabs excavating burrows.
I studied how variations in canopy cover and substratum topography influence the recruitment and demography of the mangrove Avicennia marina in a temperate forest in New South Wales, Australia.
Surveys showed that mounds covered up to 44% of the forest floor and were larger and covered more of the substratum under the canopy than in gaps. Propagules and new seedlings (i.e. the most recently established cohort) were more abundant under the canopy than in gaps and on flat areas than on mounds.
A field experiment tested whether the observed spatial distribution of new seedlings was due to differences in the secondary dispersal of propagules or in the establishment or early survivorship of seedlings. Propagules were supplied in equal densities on mounds and flats under the canopy and in gaps and then monitored for 10 months.
Four times as many propagules were dispersed away from mounds as from flats, and this difference was greater under the canopy than in gaps. In contrast, seedlings established more successfully on mounds, particularly in gaps, suggesting that this is an important microhabitat for recruitment. Seedling survival to 9 months was independent of habitat structure.
The influence of mounds on dispersal was, however, much greater than on establishment, so that densities of new seedlings 9 months after establishment were greater on flats. Patterns of seedling abundance in the mangrove forest are thus primarily driven by the influence of habitat structure on the supply of propagules.
In contrast, saplings were most abundant on mounds in gaps. Thus, there is a shift in the spatial distribution of the population from the early to the later stages of life history in relation to habitat structure. Long‐term survival of seedlings and their development into saplings may depend both on light availability in gaps and on sediment disturbance resulting from the creation of mounds. The causative agent, crabs, may therefore be critical for regeneration of mangrove forests.
The regulation of ecosystem functions by ecotypic variation in the dominant plant: a Spartina alterniflora salt‐marsh case study
Authors: Seliskar Denise M. , Gallagher John L. , Burdick David M. , Mutz Laurie A. 
Published: March 2003

Summary

Genetic differences among populations of a keystone species may affect ecosystem functional properties. We tested this by planting Spartina alterniflora from different geographical regions in a newly created salt marsh in Delaware, USA.
Spartina alterniflora plants from morphologically distinct short‐form (back marsh) populations were originally collected from Massachusetts (41°34′ N), Delaware (38°47′ N), and Georgia (31°25′ N) in the USA and vegetatively propagated for 6 years in a salt water‐irrigated common garden in Delaware before transfer to a newly created salt marsh.
The magnitude of the expression of marsh functions in the created marsh, measured over 5 years, remained distinct in patches of each ecotype. End of season aerial biomass, below‐ground biomass, root and rhizome distribution, canopy height, stem density, and carbohydrate reserves were closer to values reported for the plants’ native sites than to those typical of Delaware. Thus, many of the plant features characteristic of particular latitudes appear to be under genetic control. Such ecotypic differentiation influences ecosystem function through keystone resource and keystone modifier activities.
Respiration of the microbial community associated with either dead shoots or the soil varied with plant ecotype in the created wetland and the patterns reflected those reported for their native sites. High edaphic respiration under the Massachusetts ecotype was correlated with the high percentage of sugar in the rhizomes. Edaphic chlorophyll was greater under the canopies of the Massachusetts and Delaware ecotypes than under the Georgia canopy and exhibited a relationship similar to that of algal production rates reported for the native sites. Larval fish were most abundant in pit traps in the Massachusetts ecotype.