bluuebunny/crossref_metadata_2025_split huggingface dataset:
Speciation centres and sustainable development
Authors: Salomon Marc 
Published: October 2010

AbstractBiodiversity can be regarded as the result of the dynamic processes starting with speciation and ending with species extinction. Speciation urges populations of organisms within an already‐existing species to change as a consequence of ecological change. It can occur everywhere as the selective pressures causing it are randomly distributed (Dobzhansky et al., 1977, p. 4); hence, a need to promote a development policy that does not endanger these natural processes. This conservation concept addresses a global ecological policy and is different from the more classical concept of conservation based on the promotion of natural parks to preserve rare species and their direct habitats. The latter concept has the disadvantage to lead to the protection of limited surfaces, which cannot harbour most of speciation centres and leaves the rest of the world unprotected. Examples will illustrate the dangers faced by continental and insular speciation centres.
Diaphragmatic sulci and portal fissures
Authors: Macchi Veronica , Feltrin Giampietro , Parenti Anna , De Caro Raffaele 
Published: October 2010

AbstractDiaphragmatic sulci in the superior surface of the liver were found in 40% of cases at autopsy. All sulci were located in the right lobe and in 47% they were multiple. In order to evaluate possible predisposing factors for these accessory sulci, their topography and characteristics were observed in unfixed livers; moreover, intravenous injections of radio‐opaque resins were performed in the portal and hepatic veins (HVs). After formalin fixation, the livers underwent CT and MR scans and a three‐dimensional (3D) elaboration of the images was performed. Radiological examination revealed a correspondence between the topography of the sulci and the course of the right and middle HVs and their main tributaries in 67%. The corrosion casts showed the location of the sulci at the level of the boundaries between the ramifications of the terminal branches of the portal triad, where the HVs are located, in 73%. These findings suggest that, rather than the action of ‘special’ or hypertrophied muscle bundles, the pressure exerted by the diaphragm as a whole may be responsible for the production of sulci at the level of weak zones, represented by the portal fissures, where the watershed superficial hepatic parenchyma, owing to the absence of all but the smallest vascular branches, exhibits a lower resistance to external pressure.
Retinol‐induced apoptosis in larval pancreas of Bufo bufo
Authors: Accordi F. , Chimenti C. 
Published: October 2010

AbstractTadpoles of Bufo bufo at the end of premetamorphosis were exposed to the action of retinol diluted in the rearing water at two concentrations: 20 and 40 µm, for 48 h. Assuming that retinol causes growth suppression by cell death induction, the TUNEL reaction for the detection of apoptotic cells was performed on paraffin sections of pancreas. The results showed that retinol induced a significant dose‐dependent increase of number of apoptotic cells with respect to controls, in which apoptosis was scarce. Electron microscopic observations of treated specimens showed that the effects of retinol mostly occurred on exocrine cells: condensed crescent‐shaped nuclear chromatin, dark cytoplasm with long projections; conversely, mitochondria and endoplasmic reticulum appeared unaffected.
The three‐dimensional architecture of the notochordal nucleus pulposus: novel observations on cell structures in the canine intervertebral disc
Authors: Hunter Christopher J. , Matyas John R. , Duncan Neil A. 
Published: October 2010

AbstractCells from the nucleus pulposus of young (< 2 years) and old (> 5 years) non‐chondrodystrophoid dogs were studied using routine histology, confocal laser scanning microscopy and transmission electron microscopy. The architecture of cell structures – from the tissue scale down to subcellular scale – was reported. Clusters of notochordal cells were observed in young nuclei pulposi, ranging from 10 to 426 cells each. These clusters resisted mechanical disruption and showed evidence of cell–cell signalling via gap junctions. Cells (30–40 µm in diameter) within the clusters had a physaliferous appearance, containing numerous large inclusions which ranged from 1 to 20 µm in diameter. The inclusions were surrounded by a dense actin cortex but were not contained by a lipid bilayer. The contents of the inclusions were determined not to be predominantly carbohydrate or neutral lipid as assessed by histochemical staining, but the exact composition of the contents remained uncertain. There were striking differences in the cell architecture of young vs. old nuclei pulposi, with a loss of both cell clusters and physaliferous cells during ageing. These observations demonstrate unique cell structures, which may influence our understanding of the differences between notochordal and chondrocytic cells in the nucleus pulposus. Such differences could have substantial impact upon how we think about development, degeneration and repair of the intervertebral disc.
Septation and separation within the outflow tract of the developing heart
Authors: Webb Sandra , Qayyum Sonia R. , Anderson Robert H. , Lamers Wouter H. , K. Richardson Michael 
Published: October 2010

AbstractThe developmental anatomy of the ventricular outlets and intrapericardial arterial trunks is a source of considerable confusion. First, major problems exist because of the multiple names and definitions used to describe this region of the heart as it develops. Second, there is no agreement on the boundaries of the described components, nor on the number of ridges or cushions to be found dividing the outflow tract, and the pattern of their fusion. Evidence is also lacking concerning the role of the fused cushions relative to that of the so‐called aortopulmonary septum in separating the intrapericardial components of the great arterial trunks. In this review, we discuss the existing problems, as we see them, in the context of developmental and postnatal morphology. We concentrate, in particular, on the changes in the nature of the wall of the outflow tract, which is initially myocardial throughout its length. Key features that, thus far, do not seem to have received appropriate attention are the origin, and mode of separation, of the intrapericardial portions of the arterial trunks, and the formation of the walls of the aortic and pulmonary valvar sinuses. Also as yet undetermined is the formation of the free‐standing muscular subpulmonary infundibulum, the mechanism of its separation from the aortic valvar sinuses, and its differentiation, if any, from the muscular ventricular outlet septum.
Vascular adaptations for heat conservation in the tail of Florida manatees (Trichechus manatus latirostris)
Authors: Rommel Sentiel A. , Caplan Heather 
Published: October 2010

AbstractAlthough Florida manatees (Trichechus manatus latirostris) have relatively low basal metabolic rates for aquatic mammals of their size, they maintain normal mammalian core temperatures. We describe vascular structures in the manatee tail that permit countercurrent heat exchange (CCHE) to conserve thermal energy. Approximately 1000 arteries juxtaposed to 2000 veins are found at the cranial end of the caudal vascular bundle (CVB); these numbers decrease caudally, but the 1 : 2 ratio of arteries to veins persists. Arterial walls are relatively thin when compared to those previously described in vascular countercurrent heat exchangers in cetaceans. It is assumed that CCHE in the CVB helps manatees to maintain core temperatures. Activity in warm water, however, mandates a mechanism that prevents elevated core temperatures. The tail could transfer heat to the environment if arterial blood delivered to the skin were warmer than the surrounding water; unfortunately, CCHE prevents this heat transfer. We describe deep caudal veins that provide a collateral venous return from the tail. This return, which is physically outside the CVB, reduces the venous volume within the bundle and allows arterial expansion and increased arterial supply to the skin, and thus helps prevent elevated core temperatures.
Effects of sex hormones on the development of giant lysosomes in the proximal tubules of DBA/2Cr mouse kidney
Authors: Yabuki Akira , Suzuki Syusaku , Matsumoto Mitsuharu , Nishinakagawa Hayao 
Published: October 2010

AbstractThe DBA/2Cr mouse strain is characterized by giant lysosomes that are located in the proximal convoluted tubules of males and in the proximal straight tubules of females. In the present study, we used light microscopy and electron microscopy to investigate the effects of sex hormones on the development of these giant lysosomes. In the proximal convoluted tubules of males, giant lysosomes (large vacuolar structures observed under light microscopy) disappeared after orchiectomy but reappeared after testosterone treatment. No changes were observed after ovariectomy or estradiol treatment. In the proximal straight tubules of females, giant lysosomes (periodic acid Schiff‐positive giant granules observed under light microscopy) disappeared after ovariectomy but reappeared after estradiol treatment. After orchiectomy and testosterone treatment, the giant lysosomes did not appear. However, a number of small lysosomes (smaller than a nucleus), which were periodic acid Schiff‐positive, increased after orchiectomy and decreased after testosterone treatment. These findings suggest that lysosomes in DBA/2Cr mice are regulated by testosterone or estradiol as follows: (1) in the proximal convoluted tubules, the development of lysosomes is stimulated by testosterone but not by estradiol; (2) in the proximal straight tubules, development of lysosomes is stimulated by estradiol and inhibited by testosterone.
Differential expression of type XII collagen in developing chicken metatarsal tendons
Authors: Zhang Guiyun , Young Blanche B. , Birk David E. 
Published: October 2010

AbstractType XII collagen is a fibril‐associated collagen with multiple functional domains. The purpose of this work was to determine its role in regulating tendon matrix assembly. The temporal and spatial expression patterns of both collagen and mRNA were analysed in developing chicken metatarsal tendons using immunofluorescence microscopy, in situ hybridization and real‐time quantitative PCR. Temporally, type XII collagen was present during all stages of development (day 14‐hatch). However, spatially, type XII collagen expression shifted from the entire tendon at day 14, when the tendon is immature and fascicles are not well developed, to the interfacial matrix (endotendinium) associated with developing fascicles. This shift was obvious beginning at day 17, becoming prominent at day 19. Associated with this shift was a gradual decrease in type XII collagen reactivity in the tendon proper (non‐sheath). By hatching, the reactivity was sequestered almost exclusively to the sheaths with some reactivity remaining at the fibroblast–matrix interface within the fascicle. In situ hybridization indicated that fibroblasts in the tendon expressed type XII collagen mRNA homogeneously at day 14. However, by hatching, when the tendon matures, type XII collagen is restricted primarily to the sheath cells. Quantitative PCR analyses, of NC3 splice variants, demonstrated highest expression levels for the short splice variant mRNA at days 14–17, followed by a significant decrease at day 19 with levels remaining constant to adult. Long variant mRNA expression was highest at day 14 then decreased and was constant from day 17 to adult. These changing patterns may be related to the spatial shift in type XII collagen expression to the sheaths. Differential temporal and spatial expression patterns indicate that type XII collagen functions to integrate the developing tendon matrices and fascicles into a functional unit.
Effects of detailed information about dissection on intentions to bequeath bodies for use in teaching and research
Authors: Greene J. R. T. 
Published: October 2010

AbstractAlmost all UK medical schools teach anatomy using human bodies that have been bequeathed specifically for the purpose. Persons intending to make this most generous gift should be fully informed about how their body will be used. If detailed descriptions of dissection reduce the number of bequests, then this traditional and effective approach to anatomy teaching will have to change. To determine what effect detailed information has on intentions to bequeath, the Department of Anatomy at Bristol University sent all 139 people who asked for information, between July and December 2001, a description of dissection that included the statement ‘Anatomical examination requires that bodies be dissected (taken apart) so that the fine detail of internal structures can be seen. Organs, such as the heart, lungs and brain, are often removed from the body to allow for more detailed study.’ Views were sought by questionnaire (response rate 88%). Ninety‐nine per cent of respondents intended to bequeath their body and 88% would allow it to be used in research or teaching with the department to make the final decision. Thus the provision of detailed information about dissection should not reduce the number of bequests and this mechanism could, subject to law, make bodies available for research as well as for teaching.
Preservation of three‐dimensional capillary structure in frog muscle during aestivation
Authors: Hudson Nicholas J. , Franklin Craig E. 
Published: October 2010

AbstractIn mammals, prolonged immobilization of the limbs can result in a loss of capillary tortuosity, resulting in skeletal muscle haemorrhaging if rapid remobilization is permitted. In this study, we examined the effect of 4 months’ immobilization on semimembranosus capillary structure in the Green‐striped burrowing frog, Cyclorana alboguttata. C. alboguttata routinely aestivates as part of a physiological strategy to avoid desiccation in semi‐arid environments and, in this capacity, the hindlimbs of C. alboguttata are immobilized in a cocoon for months at a time. We found that 4 months’ aestivation had no effect on three‐dimensional capillary structure in the semimembranosus muscle and that capillary tortuosity is preserved in immobilized C. alboguttata. The preservation of capillary structure in the hindlimb muscles of C. alboguttata in part accounts for their remarkable ability to emerge with a fully competent locomotor system after prolonged immobilization.
The number of cells expressing dopamine D2 receptor mRNA in rat brain caudate putamen is higher in oestrus
Authors: Uršič Matjaž , Bavdek Srdan V. , Zabavnik Jelka 
Published: October 2010

AbstractDopamine D2 receptors (D2‐Rs) in the central nervous system are involved in the control of locomotion, cognition, emotion and neuroendocrine secretion. The intensity of cellular responses to specific stimuli is dependent on the concentration of dopamine or its agonist, and the availability, as well as the concentration, of all the other components of the signalling pathway in the cell, including the receptors. Many factors can influence the level of mRNA encoding the receptors. In order to study the changes in the level of expression of the D2‐R mRNA in the brain of female rats at different stages of the oestrous cycle, we used a quantitative in situ hybridization technique. Four groups of animals were analysed: rats in prooestrus (POE), oestrus (OE), dioestrus 1 (DOE1) and dioestrus 2 (DOE2). A 35S‐labelled riboprobe was transcribed in vitro from the 1.5‐kb D2‐R cDNA. The caudate putamen of the rats, which shows the highest level of expression of D2‐R mRNA in the brain, was examined. The number of silver grains per cell, representing hybridization of riboprobe, and the number of cells expressing the D2‐R mRNA, were counted with the computer‐assisted image analysis system Lucia‐M. Our results show that the expression of the D2‐R mRNA in the lateral striatum varies during the oestrous cycle, with the highest expression measured during DOE2. The number of cells expressing the D2‐R mRNA also changes during the different phases, with the highest number being detected in OE. This indicates that during OE more cells transcribe the D2‐R mRNA. The results suggest that the variations in the concentration of the D2‐R mRNA in the caudate putamen of the rat brain at different stages of the reproductive cycle are caused by the combination of variable expression of the mRNA per cell and different number of the cells that express the mRNA.
Structure of the pelvic and penile urethra – relationship with the ducts of the sex accessory glands of the Mongolian gerbil (Meriones unguiculatus)
Authors: Pinheiro P. F. F. , Almeida C. C. D. , Segatelli T. M. , Martinez M. , Padovani C. R. , Martinez F. E. 
Published: October 2010

AbstractThe urethra is the main place of entry for sexually transmitted pathogens. However, there is little literature on the morphology of the urogenital system, principally the urethra and ducts of the sex accessory glands. The Mongolian gerbil is an insectivorous, herbivorous and monogamous rodent with nocturnal habits; it has been used successfully as a laboratory animal since the 1960s. Therefore, the objective of the present paper was to describe the structure and ultrastructure of the urethra and its relations to the ducts of the accessory sex glands of the Mongolian gerbil (Meriones unguiculatus), contributing to the understanding of the reproductive biology of the rodent and aiming to provide data for future experimental studies. Conventional techniques of light and scanning electron microscopy were utilized. The urethra and ducts of the accessory sex glands are similar to those of the albino rat and the mouse. However, there is variation in drainage type among accessory sex glands for the inner urethra. The ducts of the seminal vesicle, the ductus deferens, drain their contents independently into the ampullary duct that opens in the urethra. The ducts of the prostate, coagulating and bulbourethral glands drain their contents independently into the urethra.
Detomidine‐Propofol Anesthesia for Abdominal Surgery in Horses
Authors: Matthews Nora S. , Hartsfield Sandee M. , Hague Brent , Carroll Gwen L. , Short Charles E. 
Published: October 2010

Objective—To evaluate propofol for induction and maintenance of anesthesia, after detomidine premedication, in horses undergoing abdominal surgery for creation of an experimental intestinal adhesion model.Study Design—Prospective study.Animals—Twelve horses (424 ± 81 kg) from 1 to 20 years of age (5 females, 7 males).Methods—Horses were premedicated with detomidine (0.015 mg/kg IV) 20 to 25 minutes before induction, and a propofol bolus (2 mg/kg IV) was administered for induction. Propofol infusion (0.2 mg/kg/min IV) was used to maintain anesthesia. The infusion rate was adjusted to maintain an acceptable anesthetic plane as determined by muscle relaxation, occular signs, response to surgery, and cardiopulmonary responses. Oxygen (15 L/min) was insufflated through an endotracheal tube as necessary to maintain the SpO2greater than 90%. Systolic (SAP), mean (MAP), and diastolic (DAP) arterial pressures, heart rate (HR), electrocardiogram (ECG), respiratory rate (RR), SpO2(via pulse oximetry), and nasal temperature were recorded at 15 minute intervals, before premedication and after induction of anesthesia. Arterial blood gas samples were collected at the same times. Objective data are reported as mean (±SD); subjective data are reported as medians (range).Results—Propofol (2.0 mg/kg IV) induced anesthesia (mean bolus time, 85 sec) within 24 sec (±22 sec) after the bolus was completed. Induction was good in 10 horses; 2 horses showed signs of excitement and these two inductions were not smooth. Propofol infusion (0.18 mg/kg/min ± 0.04) was used to maintain anesthesia for 61 ± 19 minutes with the horses in dorsal recumbency. Mean SAP, DAP, and MAP increased significantly over time from 131 to 148, 89 to 101, and 105 to 121 mm Hg, respectively. Mean HR varied over time from 43 to 45 beats/min, whereas mean RR increased significantly over anesthesia time from 4 to 6 breaths/min. Mean arterial pH decreased from a baseline of 7.41 ± 0.07 to 7.30 ± 0.05 at 15 minutes of anesthesia, then increased towards baseline values. Mean Paco2values increased during anesthesia, ranging from 47 to 61 mm Hg whereas PaO2values decreased from baseline (97 ± 20 mm Hg), ranging from 42 to 57 mm Hg. Muscle relaxation was good and no horses moved during surgery: Recovery was good in 9 horses and acceptable in 3; mean recovery time was 67 ± 29 minutes with 2.4 ± 2.4 attempts necessary for the horses to stand.Conclusions—Detomidine‐propofol anesthesia in horses in dorsal recumbency was associated with little cardiovascular depression, but hypoxemia and respiratory depression occurred and some excitement was seen on induction.Clinical Relevance—Detomidine‐propofol anesthesia is not recommended for surgical procedures in horses if dorsal recumbency is necessary and supplemental oxygen is not available (eg, field anesthesia).
The Association of Propofol Usage With Postoperative Wound Infection Rate in Clean Wounds: A Retrospective Study
Authors: Heldmann Eileen , Brown Dorothy Cimino , Shofer Frances 
Published: October 2010

Objective—To determine if the use of propofol influences the postoperative infection rate of clean surgical wounds in dogs and cats.Study Design—Retrospective study.Sample Population—863 dogs and cats undergoing clean surgical procedures.Methods—Medical and anesthetic records of surgical cases used as part of a previously described epidemiologic study on postoperative wound infection rates were reviewed. The records of all animals with clean surgical wounds were reviewed to determine if propofol had been used for anesthetic induction or maintenance during the procedure. To determine the effect of propofol use on wound infection rate, data were analyzed using Fisher's exact test, followed by multiple logistic regression to adjust for various factors, including surgery time, time from clipping to surgery, antibiotic usage, coexisting distant infection, endocrine disease, and the use of immunosuppressive drugs in the perioperative period.Results and Conclusions—Of 863 dogs and cats with clean surgical wounds, 46 received propofol as part of the anesthetic protocol. A total of 6 of 46 animals (13%) receiving propofol developed postoperative wound infections, compared with 33 of 817 animals (4%) not receiving propofol (P= .014; % difference = 9%; 95% CI = 0.5% to 24%). Adjusting for all other factors evaluated, animals receiving propofol were 3.8 times more likely to develop postoperative wound infections compared to animals not given propofol (95% CI = 1.5–9.9).Clinical Implications—Propofol is a lipid‐based emulsion capable of supporting microbial growth. Administration of a potentially contaminated solution may contribute to surgical wound infection or other patient morbidity or mortality. Strict aseptic technique in the preparation of the solution and prompt disposal of unused drug are imperative to curtail the potential for extrinsic contamination.