bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modulation of Peripheral Endogenous Opioid Analgesia by Central Afferent Blockade
Authors: Schmitt Thomas K. , Mousa Shaaban A. , Brack Alexander , Schmidt Diego K. , Rittner Heike L. , Welte Martin , Schäfer Michael , Stein Christoph 
Published: February 2004

Background
Peripheral tissue injury causes a migration of opioid peptide-containing immune cells to the inflamed site. The subsequent release and action of these peptides on opioid receptors localized on peripheral sensory nerve terminals causes endogenous analgesia. The spinal application of opioid drugs blocks the transmission of nociceptive information from peripheral injury. This study investigates the influence of exogenous spinal opioid analgesia on peripheral endogenous opioid analgesia.

Methods
Six and forty-eight hours after initiation of continuous intrathecal morphine infusion and administration of Freund's complete adjuvant into the hind paw of rats, antinociceptive and antiinflammatory effects were measured by paw pressure threshold, paw volume, and paw temperature, respectively. Inflammation and quantity of opioid-containing cells were evaluated by immunocytochemistry and flow cytometry. Cold water swim stress-induced endogenous analgesia was examined 24 h after discontinuation of intrathecal morphine administration.

Results
Intrathecal morphine (10 micro g/h) resulted in a significant and stable increase of paw pressure threshold ( P< 0.05) without changing inflammation, as evaluated by paw volume, paw temperature, and flow cytometry ( P> 0.05). At 48 but not at 6 h after Freund's complete adjuvant, the number of beta-endorphin-containing cells and cold water swim-induced antinociception were significantly reduced in intrathecal morphine-treated rats compared with those treated with intrathecal vehicle ( P< 0.05).

Conclusions
These findings suggest an interplay of central and peripheral mechanisms of pain control. An effective central inhibition of pain apparently signals a reduced need for recruitment of opioid-containing immune cells to injured sites.
Intrathecal Lidocaine Reverses Tactile Allodynia Caused by Nerve Injuries and Potentiates the Antiallodynic Effect of the COX Inhibitor Ketorolac
Authors: Ma Weiya , Du Wei , Eisenach James C. 
Published: February 2004

Background
Systemic lidocaine and other local anesthetics reduce hypersensitivity states induced by both acute inflammation and peripheral nerve injury in animals and produce analgesia in some patients with chronic pain. The mechanisms underlying the antiallodynic effect of systemic lidocaine are unclear, although most focus is on peripheral mechanisms. Central mechanisms, particularly at the spinal dorsal horn level, are less known. In this study, the authors aimed to determine whether intrathecal lidocaine has an antiallodynic effect on established mechanical allodynia in two well-characterized neuropathic pain rat models: partial sciatic nerve ligation (PSNL) and spinal nerve ligation (SNL).

Methods
Lidocaine (100-300 micro g) was intrathecally injected in PSNL and SNL rats. The withdrawal threshold of both hind paws in response to mechanical stimulation was measured using a series of calibrated von Frey filaments.

Results
This single injection reduced ongoing tactile allodynia in PSNL and SNL rats. The antiallodynic effect of intrathecal lidocaine lasted longer in PSNL (> 3 days) than in SNL rats (< 3 days). Intraperitoneal lidocaine (300 micro g) had no effect on tactile allodynia in PSNL rats. In SNL rats, prior intrathecal lidocaine (200 and 300 micro g) potentiated the antiallodynic effect of intrathecal ketorolac, a nonselective cyclooxygenase inhibitor. Intrathecal ketorolac alone had no antiallodynic effect on SNL rats. However, prior intrathecal lidocaine (100 micro g) failed to potentiate the antiallodynic effect of intrathecal ketorolac.

Conclusion
The authors' data suggest that intrathecal lidocaine possibly suppressed the hyperexcitability of the dorsal horn neurons and likely interacted with eicosanoid systems in the spinal dorsal horn.
Fentanyl Decreases Ca2+Currents in a Population of Capsaicin-responsive Sensory Neurons
Authors: McDowell Thomas S. 
Published: February 2004

Background
Neuraxial opioids produce analgesia in part by decreasing excitatory neurotransmitter release from primary nociceptive neurons, an effect that may be due to inhibition of presynaptic voltage-activated Ca2+ channels. The purpose of this study was to determine whether opioids decrease Ca2+ currents (I Ca ) in primary nociceptive neurons, identified by their response to the algogenic agent capsaicin.

Methods
I was recorded from acutely isolated rat dorsal root ganglion neurons using the whole cell patch clamp technique before, during, and after application of the micro -opioid agonist fentanyl (0.01-1 micro m). Capsaicin was applied to each cell at the end of the experiment.

Results
Fentanyl reduced I Ca in a greater proportion of capsaicin-responsive cells (62 of 106, 58%) than capsaicin-unresponsive cells (2 of 15, 13%; P < 0.05). Among capsaicin-responsive cells, the decrease in I Ca was 38 +/- 3% (n = 36, 1 micro m) in fentanyl-sensitive cells just 7 +/- 1% (n = 15, 1 micro m; P < 0.05) in fentanyl-insensitive cells. Among capsaicin-responsive cells, I Ca inactivated more rapidly in fentanyl-sensitive cells (tau, 52 +/- 4 ms, n = 22) than in fentanyl-insensitive cells (93 +/- 14 ms, n = 24; P < 0.05). This was not due to differences in the types of Ca2+ channels expressed as the magnitudes of omega-conotoxin GVIA-sensitive (N-type), nifedipine-sensitive (L-type), and GVIA/nifedipine-resistant (primarily P-/Q-type) components of I Ca were similar.

Conclusions
The results show that opioid-sensitive Ca2+ channels are expressed by very few capsaicin-unresponsive neurons but by more than half of capsaicin-responsive neurons. The identity of the remaining capsaicin-responsive (and therefore presumed nociceptive) neurons that express opioid-insensitive Ca2+ channels is unknown but may represent a potential target of future non-opioid-based therapies for acute pain.
Restoration of morphological and functional integrity in the regenerating eye of the giant African land snail Achatina fulica
Authors: Bobkova Marina V. , Tartakovskaya Olga S. , Borissenko Serguei L. , Zhukov Valery V. , Meyer‐Rochow Victor B. 
Published: February 2004

AbstractTo determine whether vision returns to its original state following eye removal in Achatina fulica, light and electron microscope examinations, electrophysiological recordings and behavioural tests were carried out on the regenerating snails. Reparative morphogenesis can result in the restoration of the peripheral sense organ even in the absence of complete regrowth of the tentacle, but it can also lead to the formation of aberrant regenerates. We found that anatomically and ultrastructurally the eyes of the ‘most normal’ regenerates were basically the same as the original eyes. Under normal conditions each eye is composed of a principal and an accessory eye, both sharing a common cornea. The only difference between regenerated and native eyes is the smaller size of the former, as a result of a reduced number of retinal cells. Electroretinographic responses revealed that the molecular mechanism of phototransduction is restored, in principle, but that flicker fusion frequency in the regenerated eye is significantly lower than in the normal eye. The directional movement to a visual stimulus (a black stripe of 45° width) had not completely recovered even 6 months after amputation. This suggests that the central projections of the optic nerve had not become fully re‐established at the time of testing.
Ultrastructure of an integumental organ with probable sensory function in Paragordius varius (nematomorpha)
Authors: Schmidt‐Rhaesa Andreas 
Published: February 2004

AbstractThe cuticle of late parasitic stages of Paragordius varius (Leidy, 1851) is composed of a layer with large fibres and a second layer (often named the areolar layer) distal from it. In this paper, organs are described that start at the basal side of the epidermis, pass the epidermis and the fibrous layer of the cuticle and merge with large, cushion‐like structures in the distal layer of the cuticle. The epidermal part of the organs is composed of darkly stained cells, which are probably in contact with the basi‐epidermal nervous system. Up to four processes of this cell traverse the cuticle. These processes might include cilia, because they contain microtubule‐like structures. The probable connection to nerve cells and the connection to the cushion‐like structures in the outer cuticular layer make it likely that the organs described here are sensory in function.
Sperm ultrastructure of the Brazilian Amazon poison frogsEpipedobates trivittatusandEpipedobates hahneli(Anura, Dendrobatidae)
Authors: Aguiar‐Jr Odair , Lima Albertina P. , Báo Sônia N. , Recco‐Pimentel Shirlei M. 
Published: February 2004

AbstractThe sperm ultrastructure ofEpipedobates trivittatusandE. hahneliis described. The spermatological characteristics are identical in both species, except for the extension of the acrosomal vesicle. The structure of the acrosomal complex is shared with species of the Bufonoidea neobatrachian lineage, which differs from the condition observed in species included in the ranoid lineage. The phylogenetic significance of the mitochondrial collar, also seen in Eubufonoidea groups, is still unclear. Also the significance of the alternative mitochondrial arrangement seen here is unclear. The perpendicular arrangement of the centrioles is also shared with the Bufonoidea and is considered a synapomorphic condition. An expanded undulating membrane and the absence of a juxtaxonemal fibre appear to be apomorphic characteristics of dendrobatid species, as also observed (homoplastically) for species ofLitoriaandCyclorana. However, the notable expansion of the undulating membrane appears to be an autapomorphy of Dendrobatidae frogs. The ultrastructural data presented here do not support the proposed placement ofE. trivittatusin a separate genus.
Observations of spermiogenesis and epididymal sperm maturation in the rufous hare wallaby, Lagorchestes hirsutus (Metatheria, Mammalia)
Authors: Johnston S. D. , Daddow L. , Carrick F. N. , Jamieson B. 
Published: February 2004

AbstractAcrosomal development in the early spermatid of the rufous hare wallaby shows evidence of formation of an acrosomal granule, similar to that found in eutherian mammals, the Phascolarctidae and Vombatidae. Unlike the other members of the Macropodidae so far examined, the acrosome of this species appears to be fully compacted at spermiation and extends evenly over 90% of the dorsal aspect of the nucleus. During spermiogenesis, the nucleus of the rufous hare wallaby spermatid showed evidence of uneven condensation of chromatin; this may also be related to the appearance of unusual nucleoplasm evaginations from the surface of the fully condensed spermatid. This study was unable to find evidence of the presence of Sertoli cell spurs or nuclear rotation during spermiogenesis in the rufous hare wallaby. The majority of spermatozoa immediately before spermiation had a nucleus that was essentially perpendicular to the long axis of the sperm tail. Nuclei of spermatozoa found in the process of being released or isolated in the lumen of the seminiferous tubule were rotated almost parallel to the long axis of the flagellum; complete parallel alignment occurred during epididymal maturation. At spermiation spermatozoa have characteristically small cytoplasmic remnants compared to those of other macropods. Unlike the majority of macropodid spermatozoa so far described, the spermatozoa of the rufous hare wallaby showed little evidence of morphological change during epididymal transit. There was no formation of a fibre network around the midpiece or of plasma membrane specializations in this region; the only notable change was a distinctive flattening of midpiece mitochondria and scalloping of the anterior mitochondrial sheath to accommodate the sperm head. Preliminary evidence from spermiogenesis and epididymal sperm maturation supports the classification of the rufous hare wallaby as a separate genus but also indicates that its higher taxonomic position may need to be re‐evaluated.
A Longitudinal Study of the Relationships Between Conscientiousness and the Social‐ Environmental Factors and Substance‐Use Behaviors That Influence Health
Authors: Roberts Brent W. , Bogg Timothy 
Published: February 2004

AbstractThe present study tested the relationships among conscientiousness‐related traits, social‐environmental factors that affect health, and substance‐use behaviors across a 30‐year period from age 21 to age 52 in the Mills Longitudinal study of women (N=99). Results showed that the trait of social responsibility (a facet of conscientiousness) assessed at age 21 predicted family, work, and substance use outcomes at midlife (age 43 and age 52). In turn, marital quality, duration of marriage, divorce, participating in paid work, status level of work, and marijuana consumption were associated with changes in social responsibility. The implications for personality, health, and personality development are discussed.
The Effect of Health Value and Ethnicity on the Relationship Between Hardiness and Health Behaviors
Authors: Harris Shanette M. 
Published: February 2004

AbstractAssociations among hardiness, health value, and health protective behaviors were examined as a function of ethnicity among 80 African American and 100 European American college students. The role of health value as moderator versus mediator in the hardiness–health behavior link was explored. Racial differences in correlations among hardiness, control, and commitment were found, with stronger relations for African American than European Americans. Moderate positive relations between hardiness, control, commitment, and health value for African American, as contrasted with weak relations between commitment and health value for European Americans, were also shown. A partial mediational effect for health value with personal distress and moderator effects for health value with personal distress and health habits were found for African American only. Race predicted hardiness variables, tobacco and alcohol use, personal distress, and health habits beyond what was accounted for by occupation and income. The ramifications of these data with regard to future studies on hardiness, health value, and health behaviors for African American are discussed.
Establishment of Sweet Birch on Surface Mine Spoil as Influenced by Mycorrhizal Inoculation and Fertility
Authors: Walker R. F. , McLaughlin S. B. , West D. C. 
Published: February 2004

AbstractInduced mycorrhization of sweet birch (Betula lentaL.) byPisolithus tinctorius(Pers.) Coker & Couch, as influenced by substrate fertility, was evaluated for its effects on seedling growth and physiology. Following a brief period in seed flats, seedlings were transplanted to mine spoil where they resided for 30 months, and three nutrition regimes were imposed throughout the study by application of differing nutrient solution concentrations. High fertility suppressed mycorrhizal formation byP. tinctoriusbut promoted that of other mycobionts.Pisolithusmycorrhization induced substantial aboveground and belowground growth as indicated by dimensions and mass for the former and mass and length for the latter but favoring root over shoot growth overall. Furthermore, these mycorrhizae were frequently able to compensate for the growth stimulation of higher nutrient additions. Measurements of xylem pressure potential and soil water potential indicated that water uptake was enhanced byP. tinctoriusduring simulated drought episodes of two durations and in subsequent recovery periods. Inoculated seedlings had higher foliar concentrations of critical nutrients, especially N, and lower concentrations of potentially phytotoxic metallic elements, particularly Mn, than uninoculated seedlings, although the latter response was absent in high fertility. Spoil analyses clearly revealed the influence of the nutrition regimes but also the effects of seedling uptake on substrate chemistry, and reinforced the findings of the foliar analysis concerning suppression of metal uptake byP. tinctorius. Collectively, these results suggest thatP. tinctoriuscan provide sweet birch an array of physiological benefits that will permit this tree species to flourish on harsh substrates such as surface mine spoils without heavy application of chemical fertilizers.
Restoration of a Limestone Quarry: Effect of Soil Amendments on the Establishment of Native Mediterranean Sclerophyllous Shrubs
Authors: Clemente A. S. , Werner C. , Máguas C. , Cabral M. S. , Martins‐Loução M. A. , Correia O. 
Published: February 2004

Abstract Limestone quarries are spread over the Mediterranean Basin and have a strong environmental impact on the landscape, causing vegetation losses and soil losses. A reclamation project was conducted in a limestone quarry, situated in Arrábida Natural Park (southwest Portugal), that is dominated by mediterranean vegetation. Revegetation was conducted using three evergreen sclerophyllous shrub species (Ceratonia siliqua, Olea europaea, and Pistacia lentiscus), and new techniques were assayed to improve plant water status and nutrient status during the first phases after plantation. A water‐holding polymer (gel), fertilizer, and mycorrhiza inoculum were applied in a factorial experiment in a randomized complete block design. The success of these techniques was evaluated during 1.5 years, through monitoring of growth and ecophysiology of plants. Plant survival was high, the lowest values (95%) being recorded in C. siliqua. There were species‐specific responses to the treatments applied. Ceratonia siliqua showed the highest growth rates and was the only species with growth stimulated by fertilizer application. However, the application of fertilizer induced changes in leaf characteristics of the other two species, increasing chlorophyll and nitrogen contents. Mycorrhiza inoculum had no effect on plant response. The addition of the water‐holding polymer induced higher midday plant water potentials in C. siliqua, O. europaea, and P. lentiscus, but in the latter two species the simultaneous addition of gel and fertilizer induced the lowest water potentials. The addition of fertilizer and gel is recommended in future revegetation programs but not the combination of both when revegetating with O. europaea and P. lentiscus. The results of this experiment indicate that the use of these mediterranean species, adapted to nutrient and water stress, can circumvent harsh conditions of the quarry.
Ecological Restoration Treatments Increase Butterfly Richness and Abundance: Mechanisms of Response
Authors: Waltz Amy E. M. , Wallace Covington W. 
Published: February 2004

AbstractFew ecosystem restoration studies evaluate whether arthropods are important components of ecosystem recovery. We tested the hypothesis that ponderosa pine restoration treatments would increase adult butterfly species richness and abundance as a direct result of increased understory diversity and abundance. To examine mechanisms that potentially affect adult butterfly distribution, we quantified host plant frequency, nectar plant abundance, and insolation (light intensity) in restoration treatment and control forests. This study is unique, because this is the first invertebrate monitoring in ponderosa pine forest restoration treatments in the U.S. Southwest and also because these treatments are the first replicated ponderosa pine restoration treatments at a landscape scale. Three patterns emerged: (1) butterfly species richness and abundance were 2 and 3 times greater, respectively, in restoration treatment units than in paired control forests 1 year after treatment, and 1.5 and 3.5 times greater, respectively, 2 years after treatment, ordination of control and treatment sampling units using butterfly assemblages showed significant separation of control and restoration treatment units after restoration treatment; (2) host plant and nectar plant species richness showed little difference between treated and control forests even 2 years after treatment; and (3) insolation (light intensity) was significantly greater in treated forests after restoration. We suggest that changes in the butterfly assemblage may occur due to light intensity effects before plant community changes occur or can be detected. Butterfly assemblage differences will have additional cascading effects on the ecosystem as prey for higher trophic levels and through plant interactions including herbivory and pollination.
Radial Dispersion of Neighbors and the Small‐Scale Competitive Impact of Two Annual Grasses on a Native Perennial Grass
Authors: Fehmi Jeffrey S. , Rice Kevin J. , Laca Emilio A. 
Published: February 2004

Abstract In California's Mediterranean type grasslands, native perennial grasses such as Nassella pulchra are surrounded by introduced annual species and these annuals are thought to have displaced natives through much of their range. Amongst other invaders, two grasses Lolium multiflorum and Bromus hordeaceus, commonly dominate portions of the grassland with potential for N. pulchra restoration. We hypothesized that competitor species differences and small‐scale gaps (150 cm2) could be important determinants of N. pulchra survival and performance on these sites. Lolium multiflorum and B. hordeaceus were planted in 20 cm diameter circular plots at a constant rate of 1 seed per cm2 surrounding newly transplanted N. pulchra plants. Nassella pulchra showed no significant effect of the species of competitor or from the distribution of the competitors. Both interspersion of patches of bare ground and separation of competitors into patches did not increase N. pulchra pre‐dawn water potential, basal area change, number of seeds produced, or average weight of seeds. The presence of L. multiflorum was associated with a decrease in N. pulchra survival compared with plots with only B. hordeaceus. Plants with increases in basal area of less than 0.75 cm2 during the growing season had 74% mortality compared with no mortality in plants with more growth. However, initial N. pulchra plant size was not a good predictor of mortality. Limiting competition from annuals may increase survival of N. pulchra plantings, but 60% of the plants survived for at least 1 year, despite being transplanted into soil containing substantial annual grass seed.