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PubMed2004

Temporal and spatial distribution of VIP, CGRP and their receptors in the development of airway hyperresponsiveness in the lungs.

To explore the role of intrapulmonary neuropeptides in the development of airway hyperresponsiveness, we established an animal model of airway hyperresponsiveness (AHR) in rabbits by using ozone exposure. With the model, after test of the mechanics of respiration and bronchoalveolar lavage assay, the levels of vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP) in the lungs were determined by radioimmunoassay, and the expression of mRNA coding receptors of these two neuropeptides was evaluated by reverse transcriptional-polymerase chain reaction (RT-PCR). At the same time, the distribution of VIP receptor-1 (VIPR1) and CGRP receptor-1 (CGRPR1) in lung tissues and its time-course were examined by in situ hybridization. The results showed: (1) in ozone-stressing groups, airway resistance increased significantly and typical inflammatory pathological changes were observed in pulmonary tissue slides, including neutrophil and eosinophil infiltration, mucus exudation and bronchial epithelial cells (BECs) shedding; (2) with elongation of ozone exposure, the levels of VIP and CGRP in the lungs increased at first, reaching a peak on d 2 to 4, then decreased slowly, and CGRP peaked somewhat earlier than VIP; (3) mRNA expression of the two neuropeptide receptors in the lungs changed in a similar manner like VIP and CGRP, but the high level of mRNA expression of VIPR1 lasted longer than that of CGRPR1; and (4) in situ hybridization for neuropeptide receptors demonstrated that, in unstressed control, VIPR1 and CGRPR1 positive cells appeared in the airway epithelium, pulmonary interstitial and focal areas of airway and vascular smooth muscles. With the elongation of ozone exposure, hybridization stained deeper and the majority of positive cells were located around the vessels and bronchus except a few in the alveoli. At 8 d, only a small number of positive cells were seen in the lungs. From the results, it is concluded that ozone-stressing can induce the development of AHR, in which VIP and CGRP may play important roles. That implies, through binding to CGRPR1, CGRP stimulates an early inflammation response which contributes in cleaning up of irritants, while VIP exerts a later dampening of pulmonary inflammation response. These two neuropeptides may play sequential and complementary roles in the development of AHR.

Animals↗
PubMed2004

[The temporal and spatial distribution of vasoactive intestinal peptide and its receptor in the development of airway hyperresponsiveness].

OBJECTIVE: To determine the possible involvement of vasoactive intestinal peptide (VIP) in the development of airway hyper responsiveness (AHR). METHODS: Twenty-five rabbits were randomly divided into five groups (5 animals each). Four groups were exposed to 2.0 ppm ozone 1 h/day for 1 (group B(0)), 2 (group B(1)), 4 (group B(2)), and 8 (group B(3)) days, respectively. The control group (group A) breathed only filtered room air. The changes of the VIP level and the mRNA expression of VIP receptor 1 (VIPR1) in the lung were detected at various ozone-stressing time points. In situ hybridization was performed to examine the distribution of VIPR1 in the lung. RESULTS: (1) The concentration of VIP in the lung increased slowly and were maximal at day 4, then returned to the normal level. (2) The changing pattern of the VIPR1 mRNA in the lung was similar to those observed for VIP. Increases in VIPR1 mRNA were detectable by 1 day and maximal by 2 - 4 days, and then decreased slowly. (3) In group A, VIPR1 was expressed on airway epithelium, in pulmonary interstitial and focal areas of airways and vascular smooth muscles. By days 2 to 4, hybridization staining increased and the majority of VIPR1-positive cells was located in the perivascular and peribronchiolar area. On day 8, very few positive cells were seen in the lung. CONCLUSION: VIP may play an important role in the development of AHR by binding with VIPR1.

Animals↗
PubMed2001

Spatial distribution of light and nutrients in some coral reefs of Costa Rica during January 1997.

The proximity of coral reefs to areas of present and future coastal development in Costa Rica highlights the need for assessing environmental conditions important to maintaining healthy corals. In January 1997 a survey of light penetration, inorganic nutrient concentrations, temperature, and salinity was conducted in the patch reefs of Bahía Culebra (Pacific Ocean) and on the Caribbean coast in the fringing reef at Parque Nacional Cahuita and near Limón. Temperature was 28 degrees C at all sites, and salinity ranged from 33 to 36 psu. Light attenuation coefficients ranged from 0.12 to 0.29 m(-1) in reef areas. Seawater nutrient concentrations were within the range of concentrations reported for tropical reef waters; combined NO3- and NO2- and PO4(3-) were each below 1 microM. NH4+ ranged from 0.2 to 7 microM, representing a significant source of nitrogen. The ratio of total dissolved inorganic nitrogen to phosphate averaged 27 for all reef waters. The high nitrate (3.6 microM) and light attenuation (0.95 m(-1)) values from the surface waters of the La Estrella plume (Caribbean coast) show that this river represents a significant source of nitrogen and light attenuation for the neighboring reefs at Cahuita. This survey provides a useful baseline for future studies, which should monitor these important coastal coral reef areas during both wet and dry seasons.

Animals↗
PubMed1992

Spatial distribution of the DF508 mutation in cystic fibrosis: a review.

The recent finding of the most common mutation (DF508) in cystic fibrosis in white populations has led to the publication of numerous data regarding its distribution and frequency. A review of the available data shows that there is a gradient in both the incidence of cystic fibrosis and the frequency of the DF508 mutation in Europe, the highest values being found in western Europe. It is postulated that the DF508 mutation was present in a western European population before the arrival of the Indo-Europeans from the Middle East; the mutation then spread into these migrating populations.

Cystic Fibrosis↗
PubMed2004

[Interrelation of matrix vesicles with spatial distribution of mineral component in fibrous and hyaline cartilages].

Mineral components of the human fibrous and hyaline cartilages were studied by the methods of light, scanning, transmission electron microscopy and cryofractography. The interterritorial matrix of the fibrous cartilage was found to contain not only the local deposits of mineral in matrix vesicles, but also the calcified collagen fibrils and interfibrillar spaces forming the collagen fibers and occupying its major part. In the hyaline cartilage and in the territorial matrix of fibrous cartilage, mineral deposits were located in mineralized conglomerates, the basis of which was formed by matrix vesicles, surrounded by collagen fibrils and interfibrillar space substance. Such conglomerates participate in the formation of calcospherites.

Cartilage↗
PubMed2004

Spatial distribution of cardiac magnetic vector fields acquired from 3120 SQUID positions.

An extended measurement of the magnetic vector field of the human heart is presented. It is acquired by sequential recordings, shifting a 16 SQUID vector magnetometer across 195 positions over a healthy subject's thorax. The magnetocardiographic (MCG) signals were synchronized using a simultaneously measured ECG channel. The registration of the field extends over a volume of 1000 mm x 600 mm x 420 mm sampled at 3120 SQUID positions. We present diagrams of the vector amplitude of selected points in 6 planes at increasing distances from the frontal thorax. Each plane contains 76 vector points. Additionally, we measured the vector field at 126 points lateral to the chest. At the edge points of the measurement volume, the absolute value of the magnetic vector signal amplitude exceeds 0.3 pT in all measurement points. The dataset provides an excellent base to study dedicated MCG detection or rejection methods. Examples where rejection of the heart signal is necessary are magnetoencephalography, magnetoneurography and fetal MCG. The knowledge of the spatio-temporal distribution of the magnetic vector field of the heart supports the development and comparison of multi-SQUID systems and will be used to create new MCG interpretation and representation algorithms.

Body Surface Potential Mapping↗
PubMed2005

Spatial distribution of anopheline larval habitats in Western Kenyan highlands: effects of land cover types and topography.

The distributions of anopheline larval habitats were aggregated in valley bottoms in Kenya in both the rainy and dry seasons, although the degree of aggregation was higher in the dry season than in the rainy season. Larvae of the Anopheles gambiae complex larvae were found more frequently in habitats in farmlands and pastures. However, An. funestus larvae were found more frequently in natural swamps and pastures. Canopy cover was the only variable significantly associated with the occurrence of the An. gambiae complex and An. funestus. The average canopy cover was significantly less in the habitats with the An. gambiae complex and An. funestus larvae than those without the anopheline larvae. Thus, land cover types and topographic features showed important effects on the distribution of anopheline larval habitats. These results suggest that clearing riparian forests would improve growing conditions of the An. gambiae complex and An. funestus larvae in Kenyan highlands.

Animals↗
PubMedDate not supplied

Spatial distribution of mast cells in chronic venous leg ulcers.

Chronic venous leg ulcers (CVUs) show chronic inflammation but different pathological changes occur in different parts of the ulcer. There is a lack of re-epithelialisation and defective matrix deposition in the ulcer base but epidermal hyperproliferation and increased matrix deposition in the surrounding skin. The role of mast cells in wound healing, inflammation, fibrosis and epidermal hyperproliferation has been extensively studied but less is known about their role in CVUs. In the present study, we investigated the distribution of mast cells in CVUs with specific consideration of the differences between the ulcer base and the skin surrounding the ulcer. Both histochemical and immunohistological methods were used to detect the mast cell marker tryptase in frozen sections of CVU biopsies. Mast cells were counted in the dermis of normal skin, in the ulcer base and in the skin surrounding the ulcer. Double immunofluorescence staining was used to study the location of mast cells in relation to blood vessels. In normal skin few mast cells were seen in the dermis but none in the epidermis. However in CVUs there was a significant increase in intact and degranulated mast cells in the surrounding skin and ulcer edge (184 per field, p<0.003) of CVUs and a significant reduction in the ulcer base (20.5 per field p<0.05) in comparison to normal skin (61 per field). In CVUs mast cells showed a characteristic location near the epithelial basement membrane whilst mast cell granules and phantom cells (mast cells devoid of granules) were predominantly seen in the epidermis. In the dermis, mast cells were seen associated with blood vessels. The marked increase in mast cells in the surrounding skin of CVUs and depletion of mast cells in the ulcer base could implicate mast cell mediators in the pathological changes in CVUs particularly in the epidermal and vascular changes occurring in the surrounding skin.

Cell Count↗
PubMed1991

Influence of vegetation on the spatial distribution of Toxorhynchites moctezuma ovipositions in the field.

The influence of the vegetation surrounding black-painted calabash ovitraps on the number of eggs of the mosquito Toxorhynchites moctezuma they attracted was investigated using oviposition data gathered from a seasonal-deciduous forest in Trinidad, West Indies. More eggs were laid into ovitraps situated either within or directly adjacent to trees or bamboo stools than those not associated with trees or bamboo. This result is discussed in terms of the initial oviposition-site searching behavior of female Toxorhynchites.

Animals↗
PubMed1991

Influence of tree trunks on the spatial distribution of Toxorhynchites r. rutilus ovipositions in a coastal oak/palm hammock in Florida.

The number of Toxorhynchites r. rutilus eggs occurring in 20 ground-level oviposition traps was monitored daily for 14 days in an area of coastal oak/palm hammock forest in Florida. Ten of these ovitraps (modified 2-liter plastic soda bottles) were placed in contact with tree trunks, the others at least 2 m from the base of the nearest tree. There was no significant difference in the mean number of eggs observed in egg-positive ovitraps for either type of trap site. However, ovitraps abutting trees were egg-positive significantly more often than expected. This result is discussed in terms of the initial oviposition-site searching behavior of female Toxorhynchites.

Animals↗
PubMed2006

[Soil organic carbon storage and its spatial distribution characteristics in Hainan Island: a study based on HNSOTER].

The study based on HNSOTER and supported by GIS showed that in Hainan Island, the total amount of soil organic carbon in the standard profile depth of 0 - 100 cm was about 2.78 x 10(8) t, and the soil organic carbon density in 0 - 20 cm and 0 - 100 cm profile depth was 0.3 - 18.8 kg x m(-2) and 1.0 - 32.1 kg x m(-2), with an area-weighted means of 3.3 kg x m(-2) and 8.4 kg x m(-2), respectively. Soil organic carbon density varied significantly with different landform, lithology and soil, which tended to decrease from the mountains in the middle part of Hainan Island to its coastal plain, and had some differences between 0 - 20 cm and 0 - 100 cm profile depth. The areas of high soil organic carbon density in 0 - 20 cm profile depth were mainly distributed in the mountains and northern basalt tableland, while those in 0 - 100 cm profile depth were in the middle-eastern mountains and tableland. The distribution center of soil organic carbon density in 0 - 100 cm profile depth had a significant shift to the eastern part, compared with that in 0 - 20 cm profile depth.

Carbon↗
PubMed1990

[Spatial distribution of the peripheral nerve lesion in polyarteritis nodosa].

We have examined the peripheral nerves in four patients with polyarteritis nodosa. They were consisted of two males and two females with the age of 70, 49, 65 and 75 years respectively. The sciatic and posterior-tibial nerves, sural nerves, ventral and dorsal spinal nerve roots, dorsal ganglia and spinal cord were removed at autopsy. Particularly, the sciatic and posterior-tibial nerves were removed as a whole and suspended in a glass cylinder with a weight and fixed in 1.5% glutaraldehyde and 0.05 M phosphate buffer, pH 7.4 for 16 hours. The nerve fragments of every 3 to 3.5 cm along the sciatic and posterior-tibial nerve were examined on conventional paraffin-embedded and epon-embedded sections, and osmicated teased-fibers. Necrotizing angitis was commonly present in the epineurium of the sciatic and posterior-tibial nerves in all four patients. Although necrotizing angitis was diffusely distributed in the proximal to distal portions of the nerve, loss of myelinated fibers, occurred only in the distal to mid-lower portions of the sciatic nerve. There was no substantial myelinated fiber loss in the proximal part of the sciatic nerve in three of four cases. Myelinated fiber loss in the fascicle was central fascicular or multiple-focal in pattern in the proximal portions of the nerve, but was diffuse in more distal portion of the posterior tibial nerve. Segmental demyelination and myelin irregularity in the teased-fiber preparation were more prominently observed in the proximal portions, but fibers with axonal degeneration were more frequent in the distal portions of the nerve.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Spatial distribution of B-like nucleotide repeats in the nuclear matrix of somatic and meiotic cells.

A comparative analysis of the content of B1-like and B2-like repeats of nucleotide sequences in the nuclei and residual nuclear structures (the nuclear matrix) of somatic and meiotic cells of the rat is presented. The B1- and B2-like repeats are mainly associated with elements of the inner matrix of somatic and meiotic cells. The observations are discussed in relation to the rosette model for the organisation of DNA in the nucleus and the role of these rosette structures in the structural organisation of eukaryotic chromosomes and certain genetic processes.

Animals↗
PubMed1990

Acoustic analysis of experimental prosthetic apparatus on spatial distribution formants.

This study concerns the effects of various prosthetic apparatus on speech perception. In this study we analyzed not only the first and second formant frequencies (as have often been studied previously) but also the third formant frequencies, and the three formant frequencies en masse. Our study demonstrated that of the six kinds of prosthetic apparatus we examined, the least effective apparatus was the L.S. type, while the most effective was the M.P. type.

Adult↗
PubMed1990

Relationship of cholesterol content to spatial distribution and age of disc membranes in retinal rod outer segments.

The initial events of visual transduction occur on disc membranes which are sequestered within the photoreceptor outer segment. In rod cells, the discs are stacked in the outer segment. Discs are formed at the base of the rod outer segment (ROS) from evaginations of the plasma membrane. As new discs form, older discs move toward the apical tip of the rod, from which they are eventually shed and subsequently phagocytosed by the adjacent pigment epithelium. Thus, disc membranes within a given rod cell are not of uniform age. We have recently shown that disc membranes are not homogeneous with respect to cholesterol content (Boesze-Battaglia, K., Hennessey, T., and Albert, A. D. (1989) J. Biol. Chem. 264, 8151-8155). In the present study, freshly isolated bovine retinas were incubated with [3H]leucine for 4 h in order to allow sufficient time for the radiolabeled proteins to become incorporated into the basal-most (newest) discs. Osmotically intact discs were then isolated. After the addition of digitonin, the discs were fractionated based on cholesterol content, and radioactivity (indicative of newly synthesized protein) was measured. Discs which exhibited high cholesterol content also exhibited high radio-activity. These results demonstrate that the cholesterol heterogeneity of ROS disc membranes is related to the age, and thus the position, of the discs in the ROS.

Animals↗
PubMed1990

[The fauna, number and spatial distribution of mites (Acari) in house dust in Moscow].

There is a wide and strong allergenic background in Moscow, which is determined by relatively high population density and regular frequency of the allergenic mites in various premises. 34 species have been identified, 5 of them are allergen producers. The mites of the family Pyroglyphidae are the main component of the house dust fauna. Dermatophagoides pteronyssinus and D. farinae distributed all over the world are predominate. A comparative evaluation of the fauna structure, numbers and frequency of the allergenic mites in the flat dust of the allergic patients and healthy people as well as premises is given. Possible importance of the premises in prevalence and circulation of the allergenic mites in the modern town is estimated for the first time.

Allergens↗