bluuebunny/crossref_metadata_2025 huggingface dataset:
CBP and p300 are essential for renin cell identity and morphological integrity of the kidney
Authors: Gomez R. Ariel , Pentz Ellen Steward , Jin Xuan , Cordaillat Magali , Sequeira Lopez Maria Luisa S.
Published: February 2009

The mechanisms that govern the identity of renin cells are not well understood. We and others have identified cAMP as an important pathway in the regulation of renin synthesis and release. Recently, experiments in cells from the renin lineage led us to propose that acquisition and maintenance of renin cell identity are mediated by cAMP and histone acetylation at the cAMP responsive element (CRE) of the renin gene. Ultimately, the transcriptional effects of cAMP depend on binding of the appropriate transcription factors to CRE. It has been suggested that access of transcription factors to this region of the promoter is facilitated by the coactivators CREB-binding protein (CBP) and p300, which possess histone acetyltransferase activity and may be, in turn, responsible for the remodeling of chromatin underlying expression of the renin gene. We hypothesized that CBP and p300 are therefore required for expression of the renin gene and maintenance of the renin cell. Because mice homozygous for the deletion of CBP or p300 die before kidney organogenesis begins, no data on kidney or juxtaglomerular cell development in these mice are available. Therefore, to define the role of these histone acetyltransferases in renin cell identity in vivo, we used a conditional deletion approach, in which floxed CBP and p300 mice were crossed with mice expressing cre recombinase in renin cells. Results show that the histone acetyltransferases CBP and p300 are necessary for maintenance of renin cell identity and structural integrity of the kidney.
Protective effects of Hsp70 on the structure and function of SERCA2a expressed in HEK-293 cells during heat stress
Authors: Fu M. H. , Tupling A. R.
Published: February 2009

Heat shock protein 70 (Hsp70) can physically interact with and prevent thermal inactivation of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) 1a, the SERCA isoform expressed in adult fast-twitch skeletal muscle. This study examined whether Hsp70 could physically interact with and prevent thermal inactivation of SERCA2a, the SERCA isoform expressed in heart. HEK-293 cells were cotransfected with cDNAs encoding human Hsp70 and rabbit SERCA2a (S2a/Hsp70). Cells cotransfected with SERCA2a cDNA and pMT2 (S2a/pMT2) were used as control. One-half of the cells was heat shocked at 40°C for 1 h (HS), and one-half was maintained at 37°C before harvesting the cells and isolating microsomes. Western blot analysis showed that Hsp70 and SERCA2a were colocalized in the microsomal fraction. The levels of Hsp70 were approximately fivefold higher ( P < 0.05) in S2a/Hsp70 compared with S2a/pMT2 and approximately twofold higher ( P < 0.05) following HS in all cells. Coimmunoprecipitation demonstrated that Hsp70 directly binds to SERCA2a. Following HS, maximal SERCA2a activity was reduced (∼52%, P < 0.05) in S2a/pMT2 but was increased (∼33%, P < 0.05) in S2a/Hsp70. Thermal inactivation of SERCA2a in S2a/pMT2 was associated with decreased (∼49%, P < 0.05) binding capacity for fluorescein isothiocyanate (FITC) and increased carbonyl (∼42%, P < 0.05) and nitrotyrosine (∼40%, P < 0.05) levels in SERCA2a. By contrast, the HS-induced increase in maximal SERCA2a activity observed in S2a/Hsp70 corresponded with no change ( P > 0.05) in FITC-binding capacity and reductions in carbonyl (∼40%, P < 0.05) and nitrotyrosine (∼23%, P < 0.05) levels in SERCA2a compared with S2a/pMT2. These results show that Hsp70 forms a protective interaction with SERCA2a during HS actually reducing oxidation and nitrosylation of SERCA2a thus increasing its maximal activity.
Dietary nitrite prevents hypercholesterolemic microvascular inflammation and reverses endothelial dysfunction
Authors: Stokes Karen Y. , Dugas Tammy R. , Tang Yaoping , Garg Harsha , Guidry Eric , Bryan Nathan S.
Published: February 2009

The nitrite anion is an endogenous product of mammalian nitric oxide (NO) metabolism, a key intermediate in the nitrogen cycle in plants, and a constituent of many foods. Research over the past 6 years has revealed surprising biological and cytoprotective activity of this anion. Hypercholesterolemia causes a proinflammatory phenotype in the microcirculation. This phenotype appears to result from a decline in NO bioavailability that results from a reduction in NO biosynthesis, inactivation of NO by superoxide, or both. Since nitrite has been shown to be potently cytoprotective and restore NO biochemical homeostasis, we investigated if supplemental nitrite could attenuate microvascular inflammation caused by a high cholesterol diet. C57Bl/6J mice were fed either a normal diet or a high cholesterol diet for 3 wk to induce microvascular inflammation. Mice on the high cholesterol diet received either nitrite-free drinking water or supplemental nitrite at 33 or 99 mg/l ad libitum in their drinking water. The results from this investigation reveal that mice fed a cholesterol-enriched diet exhibited significantly elevated leukocyte adhesion to and emigration through the venular endothelium as well as impaired endothelium-dependent relaxation in arterioles. Administration of nitrite in the drinking water inhibited the leukocyte adhesion and emigration and prevented the arteriolar dysfunction. This was associated with sparing of reduced tetrahydrobiopterin and decreased levels of C-reactive protein. These data reveal novel anti-inflammatory properties of nitrite and implicate the use of nitrite as a new natural therapy for microvascular inflammation and endothelial dysfunction associated with hypercholesterolemia.
Do mechanical gait parameters explain the higher metabolic cost of walking in obese adolescents?
Authors: Peyrot Nicolas , Thivel David , Isacco Laurie , Morin Jean-Benoît , Duche Pascale , Belli Alain
Published: February 2009

Net metabolic cost of walking normalized by body mass ( CW·BM−1; in J·kg−1·m−1) is greater in obese than in normal-weight individuals, and biomechanical differences could be responsible for this greater net metabolic cost. We hypothesized that, in obese individuals, greater mediolateral body center of mass (COM) displacement and lower recovery of mechanical energy could induce an increase in the external mechanical work required to lift and accelerate the COM and thus in net CW·BM−1. Body composition and standing metabolic rate were measured in 23 obese and 10 normal-weight adolescents. Metabolic and mechanical energy costs were assessed while walking along an outdoor track at four speeds (0.75–1.50 m/s). Three-dimensional COM accelerations were measured by means of a tri-axial accelerometer and gyroscope and integrated twice to obtain COM velocities, displacements, and fluctuations in potential and kinetic energies. Last, external mechanical work (J·kg−1·m−1), mediolateral COM displacement, and the mechanical energy recovery of the inverted pendulum were calculated. Net CW·BM−1was 25% higher in obese than in normal-weight subjects on average across speeds, and net CW·BM−67(J·kg−0.67·m−1) was significantly related to percent body fat ( r2= 0.46). However, recovery of mechanical energy and the external work performed (J·kg−1·m−1) were similar in the two groups. The mediolateral displacement was greater in obese subjects and significantly related to percent body fat ( r2= 0.64). The mediolateral COM displacement, likely due to greater step width, was significantly related to net CW·BM−67( r2= 0.49). In conclusion, we speculate that the greater net CW·BM−67in obese subjects may be partially explained by the greater step-to-step transition costs associated with wide gait during walking.
Role of ATP in the ROS-mediated laryngeal airway hyperreactivity induced by laryngeal acid-pepsin insult in anesthetized rats
Authors: Tsai Tung-Lung , Chang Shyue-Yih , Ho Ching-Yin , Kou Yu Ru
Published: February 2009

The pathogenetic mechanisms of laryngeal airway hyperreactivity (LAH) in patients with extraesophageal reflux are unclear. We recently reported that a laryngeal acid-pepsin insult produces LAH that is mediated through sensitization of the capsaicin-sensitive laryngeal afferent fibers by reactive oxygen species (ROS) in rats. Since ROS may promote the release of ATP from cells, we hypothesized that activation of P2X purinoceptors by ATP subsequent to an increase in ROS induces LAH in an inflamed larynx that has been insulted by acid-pepsin or H2O2(a major type of ROS). The larynxes of 208 anesthetized rats were functionally isolated while the animals breathed spontaneously. Ammonia vapor was delivered into the larynx to measure laryngeal reflex reactivity. Laryngeal insult with acid-pepsin or H2O2produced LAH with similar characteristics. The H2O2-induced LAH was prevented by laryngeal pretreatment with dimethylthiourea (a hydroxyl radical scavenger), suggesting a critical role for ROS. The LAH induced by both insults were completely prevented by ATP scavengers (a combination of apyrase and adenosine deaminase) or a P2X receptor antagonist ( iso-pyridoxalphosphate-6-azophenyl-2′,5′-disulfonate). Laryngeal application of a P2X receptor agonist (α,β-methylene-ATP) also produced LAH. An insult with either acid-pepsin or H2O2similarly promoted an increase in the levels of ATP, lipid peroxidation, and inflammation in the larynx. Our findings suggest that laryngeal insult with acid-pepsin or H2O2induces inflammation and produces excess ROS in the rat's larynx. The latter may in turn promote the release of ATP to activate P2X receptors, resulting in sensitization of capsaicin-sensitive laryngeal afferent fibers and LAH.
Postmenopausal hormone replacement therapy modifies skeletal muscle composition and function: a study with monozygotic twin pairs
Authors: Ronkainen Paula H. A. , Kovanen Vuokko , Alén Markku , Pöllänen Eija , Palonen Eeva-Maija , Ankarberg-Lindgren Carina , Hämäläinen Esa , Turpeinen Ursula , Kujala Urho M. , Puolakka Jukka , Kaprio Jaakko , Sipilä Sarianna
Published: February 2009

We investigated whether long-term hormone replacement therapy (HRT) is associated with mobility and lower limb muscle performance and composition in postmenopausal women. Fifteen 54- to 62-yr-old monozygotic female twin pairs discordant for HRT were recruited from the Finnish Twin Cohort. Habitual (HWS) and maximal (MWS) walking speeds over 10 m, thigh muscle composition, lower body muscle power assessed as vertical jumping height, and maximal isometric hand grip and knee extension strengths were measured. Intrapair differences (IPD%) with 95% confidence intervals (CI) were calculated. The mean duration of HRT use was 6.9 ± 4.1 yr. MWS was on average 7% (0.9 to 13.1%, P = 0.019) and muscle power 16% (−0.8 to 32.8%, P = 0.023) greater in HRT users than in their cotwins. Thigh muscle cross-sectional area tended to be larger (IPD% = 6%, 95% CI: −0.07 to 12.1%, P = 0.065), relative muscle area greater (IPD% = 8%, CI: 0.8 to 15.0%, P = 0.047), and relative fat area smaller (IPD% = −5%, CI: −11.3 to 1.2%, P = 0.047) in HRT users than in their sisters. There were no significant differences in maximal isometric strengths or HWS between users and nonusers. Subgroup analyses revealed that estrogen-containing therapies (11 pairs) significantly decreased total body and thigh fat content, whereas tibolone (4 pairs) tended to increase muscle cross-sectional area. This study showed that long-term HRT was associated with better mobility, greater muscle power, and favorable body and muscle composition among 54- to 62-yr-old women. The results indicate that HRT is a potential agent in preventing muscle weakness and mobility limitation in older women.
Prior moderate and heavy exercise accelerate oxygen uptake and cardiac output kinetics in endurance athletes
Authors: Faisal Azmy , Beavers Keith R. , Robertson Andrew D. , Hughson Richard L.
Published: February 2009

Cardiorespiratory interactions at the onset of dynamic cycling exercise are modified by warm-up exercises. We tested the hypotheses that oxygen uptake (V̇o2) and cardiac output (Q̇) kinetics would be accelerated at the onset of heavy and moderate cycling exercise by warm-up. Nine male endurance athletes (peak V̇o2: 60.5 ± 3.2 ml·min−1·kg−1) performed multiple rides of two different 36-min cycling protocols, involving 6-min bouts at moderate and heavy intensities. Breath-by-breath V̇o2and beat-by-beat stroke volume (SV) and Q̇, estimated by Modelflow from the finger pulse, were measured simultaneously with kinetics quantified from the phase II time constant (τ2). One novel finding was that both moderate (M) and heavy (H) warm-up bouts accelerated phase II V̇o2kinetics during a subsequent bout of heavy exercise (τ2: after M = 22.5 ± 2.7 s, after H = 22.1 ± 2.9 vs. 26.2 ± 3.2 s; P < 0.01). Q̇ kinetics in heavy exercise were accelerated by both warm-up intensities (τ2: M = 22.0 ± 4.1 s, H = 23.8 ± 5.6 s vs. 27.4 ± 7.2 s; P < 0.05). During moderate exercise, prior heavy-intensity warm-up (one or two bouts) accelerated V̇o2kinetics and elevated Q̇ at exercise onset, with no changes in Q̇ kinetics. A second novel finding was a significant overshoot in the estimate of SV from Modelflow in the first minutes of each moderate and heavy exercise bout. These findings suggest that the acceleration of V̇o2kinetics during heavy exercise was enabled by the acceleration of Q̇ kinetics, and that rapid increases in Q̇ at the onset of moderate and heavy exercise might result, in part, from an overshoot of SV.
Improvements in whole muscle and myocellular function are limited with high-intensity resistance training in octogenarian women
Authors: Raue Ulrika , Slivka Dustin , Minchev Kiril , Trappe Scott
Published: February 2009

Advanced sarcopenia is prevalent among octogenarian women; yet little is known about myocellular quality and plasticity in this cohort. The aim of this investigation was to examine single muscle fiber contractile function and whole muscle characteristics before and after 12 wk of high-intensity progressive resistance training (PRT) in very old (85 ± 1 yr) women (OW, n = 6). Young women [YW (21 ± 2 yr old), n = 9] were included as a control group. Whole muscle strength [1 repetition maximum (RM)] and size (CT scans) were assessed before and after PRT. Functional experiments (size, peak force, velocity, and power) were performed on vastus lateralis myosin heavy chain (MHC) I and IIa muscle fibers before and after PRT. With PRT, 1-RM strength increased ( P < 0.05) in YW (36%) and OW (26%). Thigh muscle cross-sectional area increased (5%) in YW ( P < 0.05), but thigh muscle did not hypertrophy in OW. Before PRT, there were no differences in single-fiber parameters between YW and OW. With PRT, MHC IIa fiber size (28%), peak force (31%), and power (28%) improved, but no changes were observed in MHC I fibers, in YW ( P < 0.05). There were no improvements in MHC I or IIa single-fiber function in OW. These data show that the myocellular functional profile in OW is similar to that in YW but that OW have a blunted hypertrophic response to PRT at the whole muscle and myocellular level. The limited myocellular plasticity in OW with PRT contrasts with that in YW and previous PRT studies in elderly women only a decade younger. These data suggest that attempts to greatly enhance skeletal muscle mass and function should begin before 80 yr of age.
Ramadan Fasting and the GH/IGF-1 Axis of Trained Men during Submaximal Exercise
Authors: Bouhlel Ezzedine , Zaouali Monia , Miled Abdelhedi , Tabka Zouhair , Bigard Xavier , Shephard Roy
Published: February 2009

Aims: The aim of this study was to explore possible changes in body composition, blood glucose regulation, plasma growth hormone (GH), insulin-like growth factor 1 (IGF-1), insulin-like growth factor-binding protein-3 (IGFBP-3), and insulin concentrations of trained athletes in response to the intermittent fasting and dehydration of Ramadan observance. Methods: Nine trained male rugby players (age 19 ± 2 years, height 1.78 ± 0.74 m) were tested 3 times: before Ramadan (C), at the end of the first week (R1), and during the fourth week (R2). They performed a progressive cycle ergometer test at each visit. The work rate was increased in 6-min stages corresponding to 20, 30, 40, 50 and 60% of &Wdot; max. Substrate oxidation was evaluated by indirect calorimetry. On each occasion, substrate and plasma hormone concentrations were measured at rest and at the end of the exercise. Results: Ramadan fasting induced a significant decrease in body mass and body fat (R2 vs. C, p < 0.001). Plasma concentrations of glucose, insulin, GH, IGF-1 and IGFBP-3 did not change significantly between C and R2, either at rest or following exercise. Conclusion: Ramadan fasting induces positive changes in body composition without disturbing glucose regulation or activity of the GH/IGF-1 system.
Pepsin Detection in the Sputum/Saliva for the Diagnosis of Gastroesophageal Reflux Disease in Patients with Clinically Suspected Atypical Gastroesophageal Reflux Disease Symptoms
Authors: Kim Tae Ho , Lee Kwang Jae , Yeo Marie , Kim Dong Kyu , Cho Sung Won
Published: February 2009

Background/Aims: Atypical manifestations of gastroesophageal reflux disease (GERD) are diverse. We aimed to determine whether pepsin detection in the sputum/saliva could be useful for diagnosing GERD in patients with clinically suspected atypical GERD symptoms. Methods: Patients with clinically suspected atypical GERD symptoms provided sputum/saliva collected before bedtime, at the time of those symptoms, and after awakening for pepsin measurement by Western blot analysis. All subjects received 24-hour esophageal pH monitoring, and then 40 mg of esomeprazole was given twice a day for 2 weeks. Results: The pepsin test was positive in 20 out of 40 patients, with pepsin detected mainly in the samples collected at the time of symptoms (45%). Samples collected from healthy volunteers (n = 8) were all negative for pepsin. 24-hour pH-metry was positive in 9 patients (23%). Based on 24-hour pH-metry data, the sensitivity and negative predictive value of the pepsin test were excellent in most of typical and atypical symptom groups, whereas its specificity and positive predictive value were relatively low, particularly in atypical symptom groups. Conclusions: Pepsin measurement in the sputum/saliva collected at the time of symptoms provides a sensitive, non-invasive method for diagnosing GERD in patients with clinically suspected atypical GERD symptoms.
Asymmetrical Dimethylarginine Is Increased in Plasma and Decreased in Cerebrospinal Fluid of Patients with Alzheimer’s Disease
Authors: Arlt Sönke , Schulze Friedrich , Eichenlaub Martin , Maas Renke , Lehmbeck Jan T. , Schwedhelm Edzard , Jahn Holger , Böger Rainer H.
Published: February 2009

Background: Asymmetrical dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide (NO) synthase and may alter NO production during pathological conditions. Concerning Alzheimer’s disease (AD), there are reports on altered cerebral NO metabolism, but only few studies on ADMA concentrations in plasma and cerebrospinal fluid (CSF). Methods: We assessed plasma ADMA in 80 AD patients and 80 age- and gender-matched controls and CSF ADMA in a subgroup of 53 AD patients and 20 controls. Results: ADMA plasma concentrations were increased, while CSF ADMA concentrations were decreased in AD patients. There was a significant association between decreasing CSF ADMA levels and the severity of cognitive impairment. Conclusion: Elevated ADMA in plasma might be a contributing factor for AD through alterations of NO metabolism, for example decreased cerebral microperfusion, while decreased levels of CSF ADMA might lead to a cerebral increase of NO, peroxynitrite production and oxidative protein damage. Our study reveals different mechanisms of plasma and CSF ADMA regulation, both potentially contributing to AD pathology.
Heterotopic thyroid follicles in the accessory mesonephric lobes of Heteropneustes fossilis (Bloch)
Authors: Qureshi T.A.
Published: February 2009

The presence of heterotopic thyroid follicles is reported in the accessory mesonephric lobes of Heteropneustes fossilis. They are found rarely and singly, scattered in the substance of these lobes, in the early stages of development; but in the adult organ they occur in groups. There is no regular distribution and proper arrangement of these follicles. They are mainly located in close proximity to blood vessels and are considered to have migrated to their heterotopic positions along them. They show some signs of functional activity in the adult animal.
Anatomical, neurohistological and histochemical observations on the tongue of Francolinus pondicerianus (grey partridge or safed teeter)
Authors: Purwar R.S.
Published: February 2009

The staining and demonstration of neural elements in relation with other associated structures was most satisfactory at pH 5.2, incubation period 20 h, and temperature 40 °C. Ganglia of various shape and size were observed on or near the fungiform, filiform and foliate papillae. In the region of the fungiform papillae, a chain of ganglia (parasympathetic) was observed. The nerve cells of these ganglia showed cholinesterase (ChE) activity. The neural networks of the foliate papillae were connected with the neural terminal network and occasionally to the ganglia. The innervation of blood vessels (artery and vein) was profuse. At times ganglia were noticed on the periphery of the artery. Neuromuscular spindle-like structures were noticed occasionally. Dot-like free nerve endings were also observed. The ChE activity was very marked in the muscle fibres lying in the region of the circumvallate papillae but was less marked in the muscle fibres lying in the region of the filiform and fungiform papillae.
Effects of sialoadenectomy and parotin hormone on the development of rat sponge-induced granulation tissue
Authors: Teixeira Décio , Vizioli Mário Roberto , Guimarães Alcides
Published: February 2009

A study was made concerning the effects of sialoadenectomy and parotin hormone administration upon sponge-induced granulation tissue of young adult rats. The effects of sialoadenectomy alone and sialoadenectomy plus a single subcutaneous injection of parotin hormone, in two different doses (0.15 and 0.30 mg), on the development of 15-day-old granulation tissue were observed. The action of parotin hormone administration without sialoadenectomy was also investigated. The results have shown that sialoadenectomy produces a retardation effect upon the development of the tissue. This effect was partially inhibited by 0.15 mg and totally eliminated by the administration of 0.30 mg of the hormone. When administered in rats which were not síaloadenectomized, the dose of 0.30 mg caused increased fibroplasia and vascularization of granulation tissue, while a dose of 0.15 mg did not cause any significant difference when compared to the control tissue.
Effect of glucose administration on the blood sugar and pancreatic islets of the frog, Rana tigrina
Authors: Kumar S. , Khanna S.S.
Published: February 2009

Glucose evoked significant hyperglycemia in the frog, Rana tigrina, 0.5 h after the injection and it took a longer time to regain normoglycemia than mammals, thus exhibiting a low glucose tolerance. The islet tissue of injected animals showed degranulation and atrophy of /?-cells only, the α-cells remained almost normal. This damage suggests that the β-cells of this frog are functionally like those of mammals and other vertebrates, and secrete insulin. A single dose of glucose was found incapable of producing permanent diabetes, and β-cells damage was repairable at later stages. Excess of glucose in the blood seems to stimulate secretion of insulin by the β-cells.
Secondary cartilages in growth and development of the symphysis menti in the hamster
Authors: Trevisan Roberto A. , Scapino Robert P.
Published: February 2009

The early growth and development of the symphyseal joint and pertinent adjacent regions of the mandible in the hamster, Mesocricetus auratus, are described. The joint is patent throughout life and in adults contains a large fibrocartilage which mediates mandibular movements. Evidence is presented to show that this cartilage is formed by the fusion of Meckel’s cartilage with two secondary cartilages that appear within the joint space. Evidence is also presented which suggests that cells of the symphyseal cartilage have the capacity to produce bone.
Histochemical studies on the liver of Heteropneustes fossilis treated with carbon tetrachloride
Authors: Sastry K.V. , Agrawal V.P.
Published: February 2009

The effect of carbon tetrachloride on the liver of Heteropneustes fossilis has been studied. It results in centrolobular necrosis and cirrhosis. The hepatocyte nuclei are enlarged and balloon-shaped cells are visible at a few places. There is an increase at this stage in the DNA content of the hepatocyte nucleus. The cytoplasm is heavily laden with glycogen. Fatty infiltration starts and the fat content in the cytoplasm of the liver cells is increased. After 5 h of injection, the nuclei undergo lysis followed by ruptures in the cell membrane. The DNA content is greatly reduced. There is a marked depletion in the glycogen content. The bile canaliculi are filled with the extruded cell contents. The fatty infiltration increases at this stage.
Ultrastructural study of nerve terminals in the submucous plexus and mucous membrane after extirpation of the myenteric plexus
Authors: Fehèr Elisabeth
Published: February 2009

An attempt is made to separate in the submucous plexus and mucous membrane of the chronically isolated intestine of the cat the fibers originating from the myenteric plexus and those originating from the submucous plexus by secondary degeneration after the extirpation of the myenteric plexus. A considerable part of the nerve processes in the submucous plexus originate from the cells of the myenteric ganglia and establish direct synaptic relationships between the ganglion cells, or are very close to the blood vessels. The numerous intact synapses between the different nerve elements in the submucous plexus point to local reflex connexions within the plexus itself. The degeneration of sub-epithelial nerve elements, containing always clear and dense-core (1,000–1,200 Å in diameter) vesicles besides the numerous intact nerve elements, might indicate the presence of real sensory nerve processes in this layer. The terminal fibers remaining intact after removal of the myenteric plexus contain numerous medium-sized dense-core vesicles in potassium permanganate-fixed material. This suggests that there are cells containing 5-hydroxytryptamine in the submucous plexus.
Nuclei and tracts of the di-mesencephalon of the parakeet
Authors: Verhaart W.J.C.
Published: February 2009

A number of nuclei and fibre systems of the parakeet di-mesencephalon, as visible in transverse series stained with the methods of Häggqvist and of Klüver and Barrera, have been described. In the preparations used, in which both neurones and myelinated fibres are visible, a relatively great number of elements can be distinguished, because of differences in cell and fibre content. Probably these elements are more sharply circumscribed than in the pigeon and therefore more readily visible. A few of them have been described for the first time, but they require experimental substantiation. Typical features of some nuclei and fibre systems of the parakeet have been pointed out. Attributing a certain type to the di-mesencephalon of the parakeet proved to be unfeasible, because of a deficient knowledge both about the elements studied and to their aspect in a sufficient number of other avian species. The pictures produced may be helpful in recognizing nuclei and fibre systems in other birds in which they are less distinct.
Cells of the adenohypophysis of the mink (Mustela vison) identified by immunohistochemical and functional criteria
Authors: Murphy B.D. , James D.A.
Published: February 2009

Six cell types were described in the adenohypophysis of the mink, and a putative function was assigned to each type. These cells are the two types of gonadotrophic cells, a thyrotrophic hormone (TSH) cell, a somatotrophic (STH) cell, a prolactin (PRL) cell and a corticotrophin-producing (ACTH) cell. Gonadotrophic cells were identified by an immunolocalization technique using antisera to ovine LH. TSH cells and ACTH cells were identified by ablation of respective target organs and observation of the subsequent hypertrophic cells in the pituitary, as well as comparison with published descriptions in other species. STH cells were identified by comparison with published reports. PRL cells were observed in lactating animals and animals in lactational withdrawal.
Differenzierung des Neuralrohres
Authors: Jacob H.J. , Christ B. , Jacob M. , Ahlström P.
Published: February 2009

In order to study the possible influence of adjacent structures upon differentiation and proliferation of the chick spinal cord, a piece of neural tube of chick embryos incubated for 2 days (stages 12–14 of Hamburger and Hamilton) was extirpated and replaced by an equal graft from a donor embryo of the same age. The grafts were rotated 90 or 180° around their longitudinal axis. The examination of the serial histological sections and the analysis of the distribution of mitotic density in the rotated spinal cord of embryos fixed 2–8 days after the operation led to the following results: the differences in morphogenesis and histogenesis between dorsal and ventral sectors of the spinal cord are already determined in 2-day-old chick embryos. The reversal of the neural tube at this time has no effect either upon the typical differentiation or the characteristic distribution of the mitotic cells in the spinal cord.
Caractéristiques et différences essentielles comparatives, morphologiques et topographiques, du cæcum de l’homme et des mammiféres domestiques
Authors: Simić V. , Ilić A.
Published: February 2009

The caecum in man as a part of the large colon (intestinum crassum) differs morphologically and topographically from the caecum of domestic mammals. The caecum in domestic mammals differs not only from the human caecum but also comparatively morphologically and topographically among the domestic mammals. The appendix vermiformis does not exist in domestic mammals, which represents the main difference between the human caecum and that of domestic mammals. There are certainly some differences in the physiological function of the caecum in man and the caecum in domestic mammals, which are carnivores, omnivores and herbivores.
Endocrine control of postcranial body proportions
Authors: Riesenfeld Alphonse
Published: February 2009

(1) Large amounts of testosterone have a growth-promoting effect on the relative to trunk (tr) length of the cervical section.(2) Castration produces relative lengthening of the thoracic section, i.e. stabilization of that section under conditions of tr depression. A similar stability of the thoracic section occurs in hyperpituitary females, in which that section does not participate in the growth increase of the trunk.(3) The absence of estrogen and the presence of testosterone have a growth-inhibiting effect on the length of the lumbar section, and the presence of estrogen promotes its growth.(4) The role of endocrines on sacral length is not clear.(5) The foot is the most stable part of the entire skeleton followed by the neurocranium, the long bones and the trunk, irrespective of whether growth changes have a nutritional or endocrine etiology. Among the long bones, the sternum, clavicle and tibia resist depressive changes most frequently and sacral width resists them the least.(6) Pelvic length and sacral width manifest allometric resistance to growth depression in the female but not the male rat. This helps maintain the integrity of pelvic space necessary for procreation.(7) Castration has a specific growth-depressing effect on the humerus, femur, pelvic length, sacral width, and interiliac distance. The depressing effect on pelvic space is aggravated by the androgenic function of progesterone and testosterone, but is eliminated by these androgenic hormones in interiliac space.(8) In males, an overdose of estrogen and testosterone has a growth-depressing effect on the tibia. But estrogen restores the growth-depressing effect of castration in the length of the pelvis and the width of the sacrum.(9) Testosterone treatment after ovariectomy has a growth-promoting effect on sacral width, the humerus, femur, tibia, sternum and clavicle.
Ultrastructural study on topographical variations of the ependyma in Bradypus tridactylus
Authors: Ferraz de Carvalho Claudio A. , Costacurta Leonel
Published: February 2009

An electron-microscopic study of ependymal cells in 24 different areas of the encephalic ventricular system of Bradypus tridactylus was made, with a view to making a comparative analysis, of a topographical kind, of various cell components: cilia, microvilli, plasma membrane, cytoplasmic protrusions, types of cellular junctions, ribosomes, Golgi apparatus, endoplasmic reticulum, microfilaments, microtubules, mitochondria, granules and dense bodies. There were differences in the distribution of all these cytologic elements, according to the topography, being a complement to a similar work done by the same authors with light-microscopy. By means of a morphofunctional analysis they draw the conclusion that even if one can admit the passage of substances by an intracellular route, on the other hand few facts support the idea that intracellular absorption or secretion could be considered as important phenomena in a great number of the ependymal areas studied.
Possible phylogenetical significance of the corpus callosum with special reference to the dolphin brain (Stenella graffmani)
Authors: Nieto A. , Nieto D. , Pacheco P.
Published: February 2009

The surface area of the corpus callosum was measured in several animals as compared to the brain weight. A general consideration of the importance of this structure on the phylogenetic scale, with special reference to the corpus callosum of the dolphin, Stenella graffmani, is given. Some theoretical considerations about the significance of this structure upon some specialized features are mentioned.
Transformation of the heterochromatin structure during epithelial cell differentiation in Microtus agrestis
Authors: Pera Franz , Moll† Michael
Published: February 2009

The interphase structure of the constitutive heterochromatin of the field vole, Microtus agrestis, was studied in the epithelium of the intestinal and respiratorial tracts, and was compared with the nuclear size and the proliferation rate of these tissues. For determining the nuclear structure and the mitotic and DNA labeling rate, Feulgen and HE-stained paraffin sections were used; measurements of the DNA content and of the nuclear and chromocenter areas were carried out on Feulgen-stained smear preparations of jejunal epithelial cells, nerve cells and glial cells with the integrating microdensitometer of Barr & Stroud and the image analyzer Microvideomat of Zeiss, respectively. In all epithelial tissues, a good correlation was found between the proliferating activity and structure of heterochromatin: the parts of the epithelia with a high amount of compact chromocenters in their nuclei also showed a high cell proliferation rate, whereas in differentiated, nondividing epithelial cells most of the nuclei were free of chromocenters. Between nuclei with and without chromocenters of the same tissues, size differences of about 75% were observed. The areas of chromocenters of diploid G1nuclei of glial, nerve and jejunal epithelial cells were equal (3–4.5 μm2) although the total areas of the nuclei differed to an extent of up to 1,000%. The sum of the areas of two separate chromocenters was about 10% larger than the area of a fused chromocenter.
Histochemistry of the duodenal glands of the cat and horse
Authors: Oduor-Okelo D.
Published: February 2009

The duodenal glands of cat and horse were studied using PAS, Alcian blue, dialysed iron, aldehyde fuchsin-Alcian blue and high iron diamine stains. It was found that the duodenal glands of the horse reacted positively to Alcian blue, dialysed iron stains and also took the Alcian blue stain in the combined aldehyde fuchsin-Alcian blue and high iron diamine-Alcian blue stains. Those of the cat gave negative results. These results suggest the presence of acidic groups in the mucosubstances secreted by the horse’s duodenal glands. A suggestion is put forward on the strength of the high iron diamine-Alcian blue combined stains that the acidity is due to the presence of carboxyl groups. It is suggested that the acidity may be significant in either the cellulose metabolism or the digestion of the bacterial microflora from the stomach of herbivores.
Immunoreactive LRF neurosecretory pathways in mammals
Authors: Barry L. , Dubois M.P.
Published: February 2009

Using antisera to synthetic luteinizing hormone-releasing factor (LRF) and antisera labeled with fluorescein isothiocyanate or peroxidase, it was possible in various physiological and experimental conditions to determine the topography of the LRF secretory cells in the guinea pig. The axons of these cells form a preoptico-infundibular LRF pathway, which controls the prehypophyseal gonadotropic secretion, and various ‘extrahypophyseal pathways’. These latter suggest that LRF, in addition to its prehypo-physiotropic action, may also have a neuromodulator function.
Bauplan der Lunge von Sphenodon punctatus
Authors: Willnow Ingrid , Willnow Richard
Published: February 2009

After a critical review of the literature, the authors describe the structure of the lung of Sphenodon, dealing with form, arteries, veins, and septation. The external form, circulatory pattern, degree of complication, height of the septa, vascular structure, and decrease in complication (?) are discussed from the standpoint of comparative anatomy. In an attempt to explain the unusual findings, the capacity for development of the central and subpleural type of differentiation is compared and contrasted. Obvious relations between the unusual lung structure and the phylogenetic age of the Sphenodon were sought, with the conclusion that the Sphenodon cannot be included in the Reptilian oders since its physical structure forms a class by itself.
Calcified inclusions in the superficial pineal gland of the mongolian gerbil, Meriones unguiculatus
Authors: Japha Joan L. , Eder Thomas J. , Goldsmith Eli D.
Published: February 2009

A histological and histochemical study of the pineal gland of neonatal, juvenile and adult gerbils is described. Calcified inclusions appear within pinealocytes in the superficial pineal about the third week of age, and the incidence of inclusions increases with age until, by the eleventh week, they are found in all animals. The inclusions contain an organic matrix composed of a carbohydrate, probably an acid mucopolysaccharide, complexed to protein. Calcification does not occur in the deep pineal. The data are interpreted to indicate that the formation of calcified inclusions is a normal process within the gerbil pineal. The similarity of the process of calcification in the gerbil and in the human pineal suggests that the gerbil may be the animal of choice for the controlled study of the phenomenon of pineal calcification.
Effect of surgical trauma on the endogenous heme iron in the brain
Authors: Choudhury Roy , Jew J. , Williams T.H.
Published: February 2009

Paucity of electron-microscopic studies on the fate of endogenous heme iron, released as a result of planned surgery, in the central nervous system warranted the present work. During investigations of neuronal plasticity in the cat, an experimental model, in which the proximal cut end of the vagosympathetic trunk was rerouted into the diencephalon, presented an ideal substrate for studying this problem. At 3 months, the brain tissue containing the implant was processed for light and electron microscopy and histo-chemistry. Under light microscopy, Prussian-blue-positive, dense cytoplasmic aggregates were visible within the macrophages. The cells were mostly clustered around the junctional area between the central and peripheral nerve elements. Electron-microscopic findings were highly characteristic and distinguished the macrophages from the surrounding neural elements by their rich content of electron-dense granules. While the latter were mostly scattered as free cytoplasmic particles, large aggregates of the same were also observed inside the lysosomes. Besides, a few inclusions were seen within astrocytic processes, close to the plasma membranes. At higher magnifications, the particles revealed the characteristic internal subunit structure of ferritin micelles. The uptake of hemoglobin and its subsequent conversion to ferritin within the macrophages and astrocytic processes are discussed at subcellular level in the light of other available studies.
A morphologically different type of smooth muscle cell in the inner media of the splenic artery
Authors: Feigl W. , Sinzinger H. , Howanietz L. , Leithner Ch.
Published: February 2009

A morphologically different cell type to the typically smooth muscle cell has been found in the inner medial layers of the splenic artery. Besides the morphological differences, typical criteria for a smooth muscle cell are demonstrated, giving an account of their identity. Morphological details are described. The importance of these cells as regards lesions of the vessel wall is briefly discussed.
Antagonistic compensation as a function of reduced weight bearing
Authors: John Doyle William
Published: February 2009

The principle of antagonistic compensation was presented by Riesenfeld in 1966 to explain the relative shortening and broadening of hypofunctional bones. Few studies have concerned themselves with this phenomenon, even though the causative agent(s) have not been delineated. In his study, Riesenfeld induced the hypofunction by complete unilateral and bilateral forelimb amputation. The resulting hypofunctional condition may be attributed to the lack of muscle function or to the lack of weight bearing or both in combination. In the present study weight bearing was eliminated in such a manner as to preserve muscle functioning. This was accomplished by two techniques: (1) unilateral forearm amputation and (2) unilateral humeral resection. Statistically significant differences in interindividual scapular length and breadth as well as humeral and ulnar lengths are reported. In all cases, the bones of the operated side were shorter than those of the unoperated side and the scapular breadth of the unoperated side was relatively greater. This confirms the hypothesis that weight bearing is, at least, partially responsible for the morphological changes induced by hypofunction and described by the principle of antagonistic compensation. However, as the reduction in length was of a lesser magnitude than that reported by Riesenfeld, the input of muscle function cannot be ignored. Rather, as both muscle functioning and weight bearing induce compressive force on long bones (including the scapula), both may serve to initiate the observed morphological changes through the vehicle of reduced compression.
Effect of malononitrile dimer on RNA concentration of neurons as demonstrated by azure B staining
Authors: Dhindsa Kuldip S. , Enesco Hildegard E.
Published: February 2009

Malononitrile dimer was administered to mice by single or by chronic (40 day) injections. The concentration of RNA in neurons of the brain was determined on histological sections by means of azure B staining. The nucleolus and Nissl substance of the several types of large neurons studied had a significantly higher concentration of RNA in the drug-injected than in the control animals.
Comparative ultrastructure of vallate, foliate and fungiform taste buds of golden Syrian hamster
Authors: Miller R.L. , Chaudhry A.P.
Published: February 2009

A fine-structure study of the hamster fungiform, foliate and vallate taste buds was undertaken for comparative purposes. All three taste bud types shared in common composition of the dark cells, light cells, basal cells, nerve fibers and nerve endings and undifferentiated peripheral cells, but morphological difference existed among them. The foliate and vallate taste buds were quite similar in their ultrastructural morphol ogy. Their dark cells displayed long apical necks, long apical microvilli, apical osmiophilic secretory granules and an abundant rough endoplasmic reticulum. The dark cells of the fungiform taste buds, however, showed no neck formation and lacked apical osmiophilic granules. They had short apical microvilli and relatively scant rough endoplasmic reticulum. There was no difference in the fine structure features of the light cells, basal cells and neural elements of different types of taste buds. Both light and dark cells were much more readily distinguishable in foliate and vallate buds than in fungiform buds at both light- and electron-microscopic levels. Foliate and vallate buds demonstrated homogeneous dense substance within the taste pores while fungiform pores were frequently empty. It is speculated that the differences in taste bud morphology may be due to their different lingual locations and/or may be a reflection of the differences in the inductive influences from different nerves. Furthermore, structural differences may be responsible for varying thresholds to different taste modalities.
Study on the fibre arrangement of the dorsal nerve root and its cellular constituents in the mouse fetus
Authors: Nawar Nabil N.Y.
Published: February 2009

The fibre arrangement of the dorsal nerve root was studied in the mouse fetus during early stages of development and was found to consist of two bundles at their exit from the dorsal root ganglion. This separate arrangement of the fibres could be traced along the course of the dorsal nerve root as far as the pial ring. Moreover, neurolemmal cells and neuroblasts were found dispersed along the whole course of the dorsal nerve root. Aggregations of neuroblasts surrounded by a thin fibrous capsule along the dorsal nerve root near the dorsal root ganglia were described as intermediate ganglia.
Karyometric studies of the nucleus preopticus in fish (Clarias batrachus) and toad (Bufo andersonii)
Authors: Dixit V.P.
Published: February 2009

With the object of investigating the so called ‘feedback’ mechanism, whereby hormones from the various endocrine glands influence the hypothalamus in its regulation of the hypophysial tropic hormones, the activity of the nucleus preopticus (NPO) has been studied by means of karyometry under experimental conditions to understand the endocrine nature of the hypothalamic nuclei. (1) Oestrogen and testosterone propionate caused an increase in nuclear volume of the NPO cells, which is related to the synthesis of secretion. An increase of the nuclear volume is attributed to an increase of secretion. (2) Methylthiouracil (MTU) and thiourea bring about shrinkage in nuclear dimensions (p < 0.001). Depletion of NSM is noticed in the hypothalamo-hypophysial neurosecretory system after MTU administration. (3) Two to five days’ administration brings about depletion of NSM in the cells of the NPO. Eight to 15 days’ metopiron treatment enhanced the activity of NPO cells. (4) Hypophysectomy caused shrinkage of the NPO cell nuclei, depletion of AF-stainable material in the cells of the NPO. ACTH treatment reversed these changes and brought about hypertrophy of the neurosecretory cells. (5) Neomercazole treatment and radiothyroidectomy bring about shrinkage in the NPO cell nuclei. Thyroidectomized toads when injected with thyroxine showed an enlargement of their nuclei.