bluuebunny/crossref_metadata_2025 huggingface dataset:
Absolute Quantification in Proton Magnetic Resonance Spectroscopy Is Superior to Relative Ratio to Discriminate Alzheimer’s Disease from Binswanger’s Disease
Authors: Watanabe Toshiyuki , Shiino Akihiko , Akiguchi Ichiro
Published: July 2008

Background/Aims: Although many proton magnetic resonance spectroscopy studies have assessed the relative ratios of brain metabolites from patients with dementia, absolute quantification is rare. The aim of this study is to compare the diagnostic accuracy of these 2 methods in proton magnetic resonance spectroscopy in discriminating Alzheimer’s disease (AD) and Binswanger’s disease (BD) from healthy controls (HC). Methods: The subjects were 30 AD patients, 13 BD patients and 26 HC subjects. Single-voxel proton MR spectra at short echo times were acquired from 8 volumes of interest. Results: At 80% specificity, the absolute N-acetylaspartate concentration in the hippocampus was the most sensitive measure to discriminate AD from HC, and the absolute N-acetylaspartate concentration in the anterior periventricular and deep white matter to differentiate BD from HC and AD. No relative ratio using creatine as a reference had a sensitivity over 80% at 80% specificity. The cause of disparities between the 2 methods was attributed to fluctuations in the creatine concentration. Conclusion: Our study revealed that absolute quantification is superior to relative ratio to differentiate AD and BD from HC.
The Association between APOE Genotype and Memory Dysfunction in Subjects with Mild Cognitive Impairment Is Related to Age and Alzheimer Pathology
Authors: Ramakers I.H.G.B. , Visser P.J. , Aalten P. , Bekers O. , Sleegers K. , van Broeckhoven C.L. , Jolles J. , Verhey F.R.J.
Published: July 2008

Background: Memory problems are a main feature of mild cognitive impairment (MCI) and may be related to the apolipoprotein E (APOE) Ε4 allele. We investigated whether the effect of the APOE genotype on memory in subjects with MCI was dependent on age and underlying Alzheimer disease (AD) pathology. Methods: Subjects with MCI (n = 180) were selected from a memory clinic setting. Subjects with at least one APOE Ε4 allele (n = 83) were compared to non-carriers on several memory measures. Subjects were reassessed 5–10 years later in order to identify those who developed AD. Results: In the middle-aged subgroup, the APOE Ε4 allele was most strongly related to decreased subjective organization and in the old subgroup to a decreased delayed recall. After excluding subjects with incipient AD (n = 33), results remained similar in the middle-aged subgroup, but in the old subgroup the APOE genotype was no longer associated with memory dysfunction. Conclusion: The presence of the APOE Ε4 allele is associated with impaired memory functioning in both middle-aged and old subjects with MCI, although the memory function affected varies with age. Its effect on memory function may be dependent on underlying AD pathology in elderly subjects, but not in middle-aged subjects.
Foveolitis Associated with Dengue Fever: A Case Series
Authors: Loh Boon-Kwang , Bacsal Kristine , Chee Soon-Phaik , Cheng Bob Ching-Li , Wong Doric
Published: July 2008

Background: Dengue fever (DF), a viral infection caused by dengue virus, is characterized by fever, headache, muscle and joint pains. Approximately 50–100 million people are infected annually. Ocular manifestations during DF are uncommon and include intraretinal hemorrhages and cotton wool spots; manifestations predominantly characterized by foveal involvement have not been described before in DF or any other retinopathies. We describe the clinical features of a series of patients with DF-associated foveolitis. Methods: A retrospective review of patients with maculopathy associated with DF was conducted. Patients found to have a yellow-orange lesion at the fovea, supported by a typical optical coherence tomography (OCT) finding of disruption of the outer neurosensory retina, were analyzed. Results: Ten eyes of 6 patients were studied. The mean age was 19.8 years. The mean presenting best corrected visual acuity was 6/45 (range of 6/7.5 to counting fingers). Fundus examination revealed a yellow-orange lesion at the fovea which corresponded to outer neurosensory retina disruption on OCT. Multifocal electroretinography showed decreased foveal and parafoveal responses. Treatment was variable, depended on visual acuity and ranged from observation to immunosuppression. Conclusion: Foveolitis may be associated with DF. OCT is a useful tool for the diagnosis and monitoring of progression of this condition.
Early Clinical Experience with Ranibizumab for Occult and Minimally Classic Neovascular Membranes in Age-Related Macular Degeneration
Authors: Mantel Irmela , Zografos Leonidas , Ambresin Aude
Published: July 2008

Background: In large randomized multicenter trials, ranibizumab has shown its therapeutic efficacy for exudative age-related macular degeneration (AMD). The aim of this paper is to report the real-life clinical experience with this treatment for occult and minimally classic membranes without pigment epithelium detachment. Methods: We conducted a retrospective chart review of 37 patients with occult and minimally classic neovascular membranes in AMD, without pigment epithelium detachment. Results: The mean visual improvement of 2 lines at 3, 6 and 9 months corresponds well with the results of the large trials. A mean number of 5 reinjections was reached by month 8. It may potentially exceed the mean 5.5 injections of the PrONTO study (prospective optical coherence tomography imaging of patients with neovascular AMD treated with intraocular ranibizumab). At months 6–8 recurrence was frequently observed. Conclusion: The early experience of ranibizumab in clinical practice brings similarly good results as the large-scale trials. However, interrupting the treatment too early may be a disadvantage.
Aqueous Humor and Serum Levels of Chromium in Cataract Patients with and without Diabetes Mellitus
Authors: Cumurcu Tongabay , Mendil Durali , Erkorkmaz Unal
Published: July 2008

Purpose: To evaluate the aqueous humor and serum levels of chromium (Cr) in cataract patients with and without diabetes mellitus. Methods: Levels of Cr were measured using atomic absorption spectrometry in the serum from 20 patients and aqueous humor aspirates taken during anterior segment surgery from 20 eyes of 20 patients who had diabetic cataracts and from 20 eyes of 20 patients who had senile cataract only. Results: The mean aqueous humor Cr concentration in eyes with diabetes cataract was significantly lower than that from eyes with senile cataract (p < 0.001). There was also a statistically significant difference between the serum Cr concentrations of the diabetic group and the control group (p < 0.001). Conclusion: The aqueous humor and serum Cr levels are decreased in eyes with diabetic cataract.
Predictive Factors of Attrition in a Cohort of Alzheimer Disease Patients
Authors: Coley Nicola , Gardette Virginie , Toulza Olivier , Gillette-Guyonnet Sophie , Cantet Christelle , Nourhashemi Fati , Andrieu Sandrine , Grand Alain , Vellas Bruno
Published: July 2008

Background: Attrition, i.e. patient dropout, can threaten the validity of results in longitudinal studies. The aim of this study was to identify patient and caregiver factors predictive of attrition in a cohort of Alzheimer disease (AD) patients. Methods: 686 patients with mild to moderate AD were included in the multicenter prospective REAL.FR study. Standardized gerontological evaluations were carried out twice yearly. Factors associated with attrition were assessed by survival analysis using a Cox proportional hazard model. Results: After 2 years, 278 (40.5%) patients had dropped out. Causes of attrition included refusal (20.9%), death (20.1%), institutionalization (19.8%), and loss to follow-up (19.8%). Attrition rates between each 6-month wave were constant at 12%. After adjustment, several independent factors remained associated with attrition: patients cared for by an unrelated caregiver [HR 1.7; 95% CI (1.08–2.59)], loss of autonomy [HR = 1.37; (1.03–1.82)], increasing caregiver burden [HR = 1.014; (1.005–1.022)], use of cholinesterase inhibitors [HR = 0.40; (0.27–0.59)], use of 1 to 3 other types of medication [HR = 0.57; (0.36–0.89)]. Conclusions: The identification of both patient and caregiver factors predictive of attrition is of particular interest for the development and targeting of attrition prevention strategies. In patients with chronic diseases, particular attention should be paid to caregiver well-being to limit attrition.
Mortality after a Diagnosis of Dementia in a Population Aged 75 and Over in Spain
Authors: Llinàs-Regla Jordi , López-Pousa Secundino , Vilalta-Franch Joan , Garre-Olmo Josep , Román Gustavo C.
Published: July 2008

Objectives: To examine the impact of incident dementia on the risk of death, taking into account other chronic illnesses potentially related to death. Design: Six-year, prospective, two-phase, observational cohort study. Setting: 8 municipalities from a rural area in Girona (Spain). Participants: A representative community-based cohort of 1,153 adults aged over 70 living at home at study enrolment. Measurements: Surviving participants underwent detailed clinical evaluation and were assessed by means of the Cambridge Examination for Mental Disorders of the Elderly. Relatives of deceased participants were interviewed using the Retrospective Collateral Dementia Interview. Mortality rates and relative risk of death for subjects with a diagnosis of dementia were calculated. The Cox proportional hazards regression model was used to assess the relationship between mortality and the diagnosis of dementia. Results: In this cohort, 40.0% (n = 49) of the subjects with a diagnosis of dementia died. The mortality rate specific to dementia was 1.0 per 100 person-years. Mortality risk ratios for dementia were 1.79 in men [95% confidence interval (CI) = 1.06–3.02], and 3.14 in women (95% CI = 2.04–4.85). The population death risk attributable to the diagnosis of dementia in our cohort was 11.8%. The most important mortality risks were severe dementia (hazard ratio = 5.7, 95% CI = 3.7–8.6), cancer (hazard ratio = 3.2, 95% CI = 2.2–4.5), heart disease, and an age over 85 (hazard ratio = 1.4, 95% CI = 1.1–1.9). Conclusion: Dementia is a major risk factor for death in advanced age, with the highest mortality rates in women. Moderate and severe dementia was associated with an increased mortality risk even after appropriate control of comorbid conditions.
Cameron Lesions: Unusual Cause of Gastrointestinal Bleeding and Anemia
Authors: Maganty Kishore , Smith Richard L.
Published: July 2008

Cameron lesions are linear gastric ulcers or erosions on the mucosal folds at the diaphragmatic impression in patients with a large hiatal hernia. The clinical relevance of Cameron lesions is due to their potential complications such as gastrointestinal bleeding (acute, chronic and obscure) and anemia. The diagnosis is usually made during upper endoscopy. Medical therapy is the mainstay of treatment with few cases reserved for surgical correction.
Das menschliche Daumengrundgelenk – ein Eigelenk
Authors: Reimann Reinhold , Ebner Inge
Published: July 2008

The metacarpophalangeal joint of the human thumb (Articulatio metacarpophalangea pollicis) is an ellipsoidal (condyloid) joint. The head of the first metacarpal bone is shaped like a spindle polled at either end. Its form relevant to the mobility is determined by the correlation of two flexures, expressed by the quotient R/r, where R = semi-diameter of the radio-ulnar flexure and r = semi-diameter of the dorso-palmar flexure in the middle of the head. Only the substantial kind of motion (flexion – extension) maintains the perfect contiguity of the articular surfaces. Owing to the deformability of the articular cartilage, the actual littleness of the articular surfaces as well as the relative smallness of the cavity with respect to the head permits both transverse motions (adduction – abduction) and axial motions (rotation inward and outward). The amplitude of the transverse motion unexpectedly does not correlate to the intensity of the radio-ulnar flexure of the head.
Observations on the pia-arachnoid of the anterior median fissure and the posterior median sulcus of the fetal spinal cord of the albino mouse
Authors: Nawar Nabi N.Y.
Published: July 2008

In the spinal cord of mouse fetuses, the pia-arachnoid lying in relation to the dorsal extremity of the posterior median septum forms two prolongations delimited laterally by veins that drain into the posterior spinal vein. A similar arrangement was met with in the anterior spinal veins. Definite cell columns in some instances and cell clusters in others were recognized in the arachnoid prolongations. The possibility that these arachnoid prolongations with the cells they contain constitute a route connecting the spinal cerebrospinal fluid with the venous blood stream is discussed.
Monoamiergi innervation of the carotid sinus in mammals: a histochemical study
Authors: Stanton P.D. , Hinrichsen C.F.L.
Published: July 2008

The bifurcations of the common carotid arteries in the rabbit, cat, pig, rat and guinea pig were examined for the comparative structure and adrenergic innervation of the carotid sinus. The carotid sinus was poorly innervated in the cat, pig and guinea pig but densely innervated in the rabbit. No adrenergic innervation could be detected in the carotid arteries or carotid sinus of the rat. The relationship of adrenergic innervation to the tunica media also varies between species, penetration being pronounced in the pig, occasional in the cat and rabbit and very slight in the guinea pig. The arrangement of adrenergic nerve fibres is circular in the cat and pig, circular and plexiform in the guinea pig and spiral in the rabbit where an additional longitudinal plexus is present. The functional implications of species variations in innervation of the carotid sinus region in relation to cardiovascular control is discussed.
Morphology of the male accessory organs of reproduction of immature fallow deer (Dama dama L.) with particular reference to puberty and antler development
Authors: Chapman D.I. , Chapman Nσrma G.
Published: July 2008

The accessory organs of reproduction of male fallow deer are fully active for the first time during the animal’s second rut, at 16 months of age. Antler pedicles develop at about 9 months, at the same time as the seminiferous tubules show a marked increase in diameter. The accessory organs show an increase in size at approximately 14 months of age when the deer weigh about 45 kg and maturation of the first pair of antlers is occurring. Puberty commences at about 9 months, pauses during the period of active antler growth and recommences at about 14 months, culminating with the appearance of spermatozoa at 16 months of age. Androgenesis precedes spermatogenesis.
The urinary bladder epithelium of the rat
Authors: Malczak Henryk T.
Published: July 2008

The surface of the urinary bladder of the rat appeared to have a very well-ordered arrangement when viewed with the help of the scanning electron microscope. Intercellular junctions were well demarcated by prominent ridges. The majority of cells appeared to have a pentagonal or hexagonal shape. The surface morphology of the epithelial cells appeared to be consistent throughout the whole population of cells. It was made up of small ridges and some short microvilli. Comments on the significance of the surface specialization were made.
Contribution à I’étude de I’nnervation sensitive de la coque talonnière
Authors: Mestdagh H. , Houcke M. , Moulront S. , Laraki A.
Published: July 2008

The purpose of the present work was to contribute to the knowledge of the subcutaneous innervation of the heel. The small branches arising from both tibial and sural neves below the ankle joint were studied by means of a dissecting microscope; this study was combined with a histological examination of the nerve endings. In spite of many individual variations, it may safely be assumed that the nervus tibialis supplies the plantar area of the heel; thin anastomoses with branches of the sural nerve were found along the lateral aspects of the heel and Achilles tendon. Moreover, based on the density of Pacinian corpuscles, the heel may be divided into three functional areas of increasing sensitivity: the Achilles area, the apex and the bearing area.
Quantitative studies on the contiguity of muscle fibre types in normal and hypertrophic skeletal muscles
Authors: James N.T.
Published: July 2008

Skeletal muscles consist of an heterogeneous population of muscle fibres. A method for deriving an index of contiguity for any of the fibre types is proposed. This term is defined as the proportion of the total boundary length (interface) of a fibre type which is in contact with fibres of the same type. It can be measured on any type of skeletal muscle independently of its composition. Values for the index of contiguity for the two major types of fibre in normal and hypertrophic extensor digitorum longus muscles of the mouse do not seem to differ.
The ultrastructure of collagenous fibers in bone marrow long-term cultures
Authors: Shvelidze T.I. , Tsagarelli Z.G.
Published: July 2008

The bone marrow of resected bones was studied by electron microscopy before and during cultivation on the 9th, 13th and 15th day of explantation. The absence of collagenous fibers in the inoculum and its appearance in individual sites in 9-day cultures simultaneously with growth of fibroblasts, in numerous sites in 13-day cultures and in almost all sites in 15-day cultures point to the appearance and growth of coUagenous fibers after a certain cultivation time. This is also confirmed by the appearance, in the latest cultures, of coUagenous fibers with transverse striation, which indicates that they mature during cultivation. The results obtained may serve as evidence of growth of collagen-producing cells (true fibroblasts) in the above-mentioned cultures.
On tannic acid fixation and staining
Authors: Chew E.C.
Published: July 2008

Tannic acid was found to fix and stain glycocalyx heavily. After removal of the major component of surface glycopeptides by trypsin, the surface coat was stained vaguely, and after the treatment with collagenase, the surface coat was moderately stained. It is concluded that tannic acid stained non-specific surface glycopeptides.
Non-specific esterase in the alveolar tissues of hamster lung: an elctron microscope study
Authors: Meban C.
Published: July 2008

The fine-structural localization of non-specific esterase was studied in the alveolar tissues of hamster lung by incubating sections of glutaraldehyde-fixed tissues in a medium containing lead ions and thiolacetic acid. The nature of the reactive enzymes was determined by exposing some sections to different inhibitors. The results showed that nonspecific esterase activity was strongest in the inclusion bodies and vacuoles of alveolar macrophages. Weaker reactions were detected in the inclusions of type II pneumonocytes, the specific granules of eosinophilic and polymorphonuclear leucocytes, and the dense bodies of type I pneumonocytes and septal fibrocytes. It is suggested that the esterase within the alveolar macrophages and type II pneumonocytes may be responsible for the catabolism of surface-active lipids.
Stabilization of the remaining adrenal gland following unilateral adrenalectomy
Authors: Ray Prajna Kumar
Published: July 2008

The effects of unilateral adrenalectomy on the contralateral adrenal gland in rats form the basis of the present communication. The project has been undertaken in an attempt to establish on ultrastructural grounds the stage at which an animal is stabilized on a solitary adrenal gland. The work is chiefly based on electron microscopy, supplemented by gross morphological and light microscopic investigations. Morphological changes in the adrenal gland after removal of the contralateral one were confined exclusively to the cortex and did not involve the medulla. The changes in the fine structure involved most of the organelles that are known to play vital roles in the biosyntheseis of corticosteroid hormones, namely, mitochondria, smooth endoplasmic reticulum (SER) and lipid droplets. The ultra-structural alterations showed remarkably wide variations at different time periods after the operation. The organelles eventually reverted to normal appearances after the 2nd postoperative week. These results have been correlated with the observations of previous workers, and the significance of the present findings, particularly in relation to the functional activity of the adrenal cortex, has been discussed.
Quantitative studies on the ultrastructural differentiation and growth of mammalian cardiac muscle cells
Authors: Hirakow Reiji , Gotoh Tadashi
Published: July 2008

The guinea pig is a nest-quitter or nidifugous mammal which develops almost to the weaning stage before birth. Myocardial cells of the bilateral atria and ventricles of guinea pigs were examined for comparison with the rat by an ultrastructural quantitative method during the pre- and postnatal developmental periods, at copulation ages of 50, 57, 64 (term), 73 and 80 days. Throughout the developmental stages, no clear differences between the right and left sides were found in the characteristics of the myocardial cells. At the stage of day 57, T-tubules were first recognized in the ventricular muscle cells, and at the same time the fiber thickness of the ventricular muscle cells (8–9 µm) became greater than that of the atrial cells (6–7 µm). At this stage, the fraction of mitochondria was also found to differ between the atrial and ventricular muscle cells. The general cellular features appeared to change more greatly during the last prenatal week from copulation day 57 to day 64 (term) than during the first postnatal week. Thus, the last prenatal week in the ontogeny of the guinea pig may be interpreted as corresponding to the postnatal period from the 10th to the 20th day in the ontogeny of the rat.
Assessment of the interbulbar connections in the cat using the Fink-Heimer and HRP methods
Authors: Ryu Takao , Santonishi A.
Published: July 2008

The anterograde degeneration technique, using the Fink-Heimer method, and retrograde cell tracing with horseradish peroxidase (HRP) were used to analyze the afferent and efferent fiber projections of the olfactory bulb complex, consisting of the main olfactory bulb (MOB), the anterior olfactory nucleus (AN) and the accessory olfactory bulb (AOB) in the cat. The results reveal that the ipsilateral and contralateral fibers running via the anterior commissure to join the internal plexiform layer of both the ipsilateral and contralateral MOBs originate from the AN, whereas the ipsilateral fiber terminals running into the outer part of the plexiform layer of the pyriform cortex originate from the MOB and AOB. In consideration of the olfactory functional relays, it is suggested that the AN, both in the dorsolateral part and external layer, most likely stimulates some afferent and efferent impulses of the olfactory impact in the mammal.
Effects of vagotomy on the ultrastructure of the parathyroid gland of the rabbit
Authors: Isono Hideo , Shoumura Shizuko
Published: July 2008

Ultrastructural changes of the parathyroid glands of vagotomized rabbits were examined. Many chief cells at 6, 12, 18 and 24 h after vagotomy are rich in free ribosomes compared to control rabbits. The main changes in the parathyroid glands of rabbits at 12, 18 and 24 h after vagotomy as compared with the control animals are a proliferation of the Golgi complexes, an increased number of secretory granules in the peripheral cytoplasm, and a frequent occurrence of enlarged intercellular spaces containing finely particulate substance. Large secretory granules, heterogeneously dense bodies, multivesicular bodies and lipid droplets apparently decrease in number in many chief cells at 12, 18 and 24 h after the operation. These alterations suggest that synthesis and release of parathyroid hormone are stimulated in many chief cells of the vagotomized rabbits. In addition, correlations of the occurrence of large secretory granules and various bodies are discussed.
Postnatal development of the kidney juxtaglomerular apparatus in rats
Authors: Vesna Lačković , Spomenka Mujović
Published: July 2008

The development of the juxtaglomerular (JG) apparatus in the rat kidney was investigated at different times of postnatal life (1, 2, 3, 5, 7, 10, 15, 30 and 60 days). On the 1st day after birth, secretory granules were found in JG cells in preglomerular arterioles of juxtamedular nephrons and in interlobular arteries. JG indices are high at this stage and decrease until the 5th day, then gradually rise until the 60th day. The possible reasons for such findings are discussed. Macula densa cells start to differ as early as the 1st day after birth. They are very distinct already at 2 days and they reach typical organization by the 15th day. Extraglomerular mesangial cells are few in early postnatal life. Their number increases later on. The parallelism between nephrogenesis and development is discussed.
Histological and ultrastructural observations of eosinophilic keratohyalin granules in filiform papillae of pig tongue
Authors: Boshell Jerry L. , Singh Baldev B. , Brewer Phyllis D.
Published: July 2008

Cells in filiform papillae of pig tongue possess distinct granules that stain with eosin but little or none with hematoxylin. This eosinophilia differs from the classically described basophilia of keratohyalin granules as is described in skin and keratinized oral mucosa of many species. At the ultrastructural level, electron-dense granules were observed in the cytoplasm and occasionally in the nuclei of cells within the papillae. The granules were round, oval or irregular in shape and varied in size and density. The ultrastructural characterization of these eosinophilic granules is the first reported in the literature.
Comparative histochemical localization of some hydrolytic enzymes in mammalian epididymides
Authors: Moniem K.A.
Published: July 2008

The activity of enzymes hydrolyzing sodium-β-glycerophosphate, adenosine triphosphate, adenosine monophosphate, and glucose-6-phosphate in the epididymides of adult ram, rabbit, rat and hamster has been investigated histochemically. The enzymes hydrolyzing sodium-β-glycerophosphate, adenosine triphosphate and adenosine monophosphate were rather similar in their distribution in the intertubular connective tissue of the epididymides of the four species studied. However, the distribution and activity of these enzymes in the stereocilia varied. There was a high activity in the stereocilia of the middle segments of ram, rabbit and rat and in the proximal part of the terminal segment of hamster epididymides. Glucose-6-phosphatase was distributed homogeneously in the epithelial cells of the epididymides throughout the duct. The possible functions of these enzymes in the mammalian epididymis are briefly discussed.
Effect of oestrogen on muscle development of female rabbits
Authors: Ihemelandu E.C.
Published: July 2008

The effect of oestrogen on muscle development was determined in 8 muscles (soleus, gastrocnemius, long digital extensor, superficial digital flexor, biceps brachii, brachialis, common digital extensor and triceps brachii) of sexually immature female rabbits. Each rabbit was treated with a physiologic dose of 0.1 ml of stilboestrol dipropionate (synthetic oestrogen) weekly from 3 to 8 weeks of age. The muscle growth, ad determined by increase in muscle weight, was significantly slower in the muscles of oestrogen-treated rabbits as compared with normal rabbits. The degree of the effect of oestrogen varied from one muscle to another.
Effect of heating on the hardness of human bone
Authors: Ramrakhiani Meera , Pal Deepti , Datta S.C.
Published: July 2008

Specimens of dry human bone were subjected to gradual or sudden heating up to different temperatures. After heating they were cooled suddenly or gradually to room temperature. Their hardness was studied by the Vickers and ball indentation tests. The deformation produced was studied by interferometric and phase-contrast techniques. Heating caused the bone to become brittle without any considerable changes in the surface features. Gradual cooling induced surface hardening. Heating was not found to affect indentation-induced surface distortion.
The ultrastructure of epithelioid cells in the avian (Gallus domesticus)carotid body
Authors: Dreyer Maria V. , de Boom H.P.A. , de Wet P.D. , Hugo N. , Eloff F.
Published: July 2008

10 clinically healthy white leghorn males were utilised for this investigation. Apart from toluidine blue-pyronin-stained Araldite sections, uranyl acetate and lead monoxide staining revealed three types of epithelioid cells. Nuclear and cytoplasmic contents, especially three types of granules, conveniently designated as q, r and p granules, are described in detail and tabulated. Technical difficulties in obtaining carotid body tissue as well as clear-stained sections for ultrastructural studies are mentioned.
Morphometric analysis of parathyroid glands in neonatal and growing dogs
Authors: Wild P. , Manser E.
Published: July 2008

In dogs aged 6 days or 5 months, the parathyroid (PT) glands exhibited differences of both the distribution and ultrastructure of dark and light cells. Morphometric estimates of cytoplasm, nucleus, mitochondria, rough endoplasmic reticulum (rER), Golgi apparatus, secretory granules, lysosomes and plasma membranes of both dark and light cells were obtained by point counting volumetry from PT glands of dogs of the two age groups and calculated per one hypothetical average PT cell. It was evident that in the PT glands of 6-day-old puppies the volume of the average PT cell was significantly smaller than in the PT glands of the 5-month-old dogs, but the cell surface was not significantly different. The volume of mitochondria, rER and lysosomes was higher in the average PT cell of the 5-month-old dogs, whereas the surface of Golgi apparatus and rER did not differ. Though the difference of the cellular and mitochondrial volume is probably related to the age difference between the two groups, the findings on Golgi apparatus, plasma membranes and lysosomes suggest that the secretory activity or at least the potency for the secretion of parathyroid hormone was higher in PT glands of the 6-day-old dogs than in the 5-month-old dogs.
Response of dog parathyroid glands to short-term alterations of serum calcium
Authors: Wild P. , Becker M.
Published: July 2008

Parathyroid (PT) glands of dogs were exposed to low or high serum calcium by infusion of either EGTA or CaCl2. Infusion of EGTA resulted in an increase of parathyroid hormone (PTH) and infusion of CaCl2, in a decrease of this hormone. The PT glands excised either at the beginning or at the end of the infusions were examined by electron microscopy. After infusion of EGTA, activated cells showed a dense matrix, prominent Golgi apparatus, rough endoplasmic reticulum (rER) with narrow cisternae, and an increased tortuosity of the plasma membrane, accompanied by an enlargement of the intercellular spaces. Infusion of CaCl2 resulted in a distention of the rER cisternae, disorganization of the Golgi apparatus and a decreased tortuosity of the plasma membrane. It is concluded that (1) PT cells may contract in the course of activation; (2) storage capacity for PTH is low, and (3) PT cells may be stimulated or inhibited to promote biosynthesis of PTH within minutes.
T-tubules, couplings and myofibrillar arrangements in rat atrial myocardium
Authors: Leeson T.S.
Published: July 2008

Myocardial cells of rat atria have been studied using standard fixation and tannic acid mordanting. Cells were arranged in bundles or fascicles with little connective tissue. Fiber size varied, with complex cell junctions and in many fibers, particularly those of small diameter, no T-tubules or internal couplings were seen. Most cells, however, contained T-tubules, mainly coupled as triads at Z-lines but showing considerable variation in morphology. Direct continuity of T-tubules with the sarcolemma was demonstrated. Apparently unrelated to T-tubules and internal couplings, all cells showed the presence of peripheral couplings between sarcoplasmic reticulum and sarcolemma and, often, the sub-sarcolemmal element of reticulum was observed to pass internally in the sarcoplasm from a peripheral coupling. Also present were subsarcolemmal caveolae. The occasional presence within a single cell of myofibrils orientated in different planes was noted also. The findings are discussed in relation to the role of T-tubules and couplings in excitation-contraction.
Fetal hepatic vessels and subsegmentation with evidence of further subdivision
Authors: Nawar N.N.Y. , Mikhail Y. , Bahi el Din I.A.
Published: July 2008

The livers of stillborn infants varying in gestational age between 6 and 9 months were studied morphologically by dissection and through preparation of corrosion casts of the portal veins and hepatic arteries. The portal veins showed strict territorial distribution. Variations in the ramifications of the area veins were met with. Also the right and left portal branches, together with certain area veins, constituted venous arcades. Planes within the territory of the portal vein were noticed to separate the territories supplied by the area vein and the area artery. A plane separating the territories of the anterior and posterior segmental veins and another, separating the territory of the posterior superior and posterior inferior areas, were met with, coinciding with fissures on the inferior surface of the liver. Moreover, intraquadrate and intracaudate fissures coinciding with planes separating the territories of ramification of the two main branches in each area, were recognized, denoting the possibility of further subdivision.
Lipids in the liver and kidney of rats, fed various heavy metals
Authors: Rana S.V.S. , Kumar Ajay , Bhardwaj N.G. , Kumar Avinendra
Published: July 2008

Interference of few heavy metals, i.e. mercury, lead, molybdenum, copper, cadmium and zinc with the hepatic and renal lipids has been estimated employing histochemical and biochemical parameters. The results show that mercury and molybdenum stimulate the accumulation of lipids whereas cadmium and zinc inhibit their restoration both in the liver and kidney. Lead and copper only raised the lipid contents of the kidney. It has been suggested that mercury and molybdenum increase the input of free fatty acid causing triglyceride formation and inhibit mitochondrial phosphorylation. Partial loss of lipids after cadmium and zinc treatment has been explained by a reverse hypothesis. Inhibition of esterases has also been proposed as the reason for increased phospholipid accumulation. However, differential effects of lead and copper on the liver and kidney suggested that a given mechanism may vary from one physiological state and pathological condition to the other.
Über die Striae medullares ventriculi quarti
Authors: Schabus R. , Firbas W. , Kern H.
Published: July 2008

On 820 human brains the presence and the course of the striae medullares of the fourth ventricle were investigated. The quantity of the various forms was studied; in 40% of cases a symmetrical and in 60% an asymmetrical situation was seen. 34 different forms were described.
Effect of natural litter size on the post-natal growth in CF rats
Authors: Padmanabhan R. , Singh Shamer
Published: July 2008

The litter effect among natural litters (with minimal differences in size i.e. 6, 8 and 9) on the growth was studied in CF rats from post-conception (PC) day 22 to 90 by somatometric techniques. Body weight was found to be significantly low in larger litters up to PC day 50 although the difference persisted numerically until PC day 90. Crown-rump length, tail length and patellocalcaneal length were significantly ( < 0.001) reduced in larger litters. Growth rate curves substantiated these observations. Since the differences in size among the three groups of litters were too small to cause any nutritional deprivation and the natural potential for growth was not altered, differences in mother-offspring and/or offspring-offspring emotional interactions could be the possible factor responsible for the growth rate differences.
Circadian variation in the structure of mast cells
Authors: Polat Can
Published: July 2008

Circadian variation in the structure of mast cells has been demonstrated histologically. At 11.00 h the number of mast cells was increased and at 03.00 h it was significantly decreased (p < 0.01). Morphological analysis has also supported this phenomenon.
Histology and cytology of the islets of Langerhans in the Mongolian gerbil (Meriones unguiculatus)
Authors: Findlay J.A. , Thomas N.W.
Published: July 2008

The histology and cell types of the islets of Langerhans were studied in the Mongolian gerbil during post-natal development using granule stains, fluorescence methods and electron microscopy. Relative islet volume, islet size distribution, islet-duct association, islet-fat association, α- and D cell populations and the size distribution of secretion granules in islet cells were quantified. In adult gerbils islets have an elliptical profile enclosed by a thin collagenous capsule, a central core of β-cells, a peripheral shell of α-cells and an incomplete layer of D cells between. In animals of 1 week or less, islets lack a capsule, are poorly vascularized and not innervated, though α-, β- and D cells are present. α-Cells exhibit green fluorescence during these early stages that disappears when adrenergic nerve fibres grow into the islets. Electron microscopy shows a fourth (unidentified) granular islet cell type, and small granular cells, that probably correspond to intensely fluorescent cells, were found within islets and neuroinsular complexes.
Electron-microscopic study on the development of permanently proliferated and cornified vaginal epithelium in mice treated neonatally with androgen
Authors: Iguchi Taisen , Ohta Yasuhiko
Published: July 2008

In the vaginal epithelium of mice given 5 daily injections of 100 µg 5α-dihydrotestosterone from the day of birth, highly electron-dense cells with numerous cytoplasmic processes appeared in the basal layer within 35 days after the last injection. These cells were similar to the B cells reported in earlier works in neonatally estrogen-treated mice undergoing ovary-independent, permanent proliferation and cornification. The present electron-microscopic study suggests that the permanently proliferating, highly electron-dense cells are derived from electronlucent cells (clear cells) appearing in the basal layer of the vaginal epithelium 15–20 days after neonatal androgen treatment.
Monoaminergic pathways to the coronary arteries and to the myocardium
Authors: Doležel S. , Gerová M. , Gero J. , Sládek T. , Vašků J.
Published: July 2008

The monoaminergic innervation of the coronary vessels and of the myocardium in dogs was examined by means of degenerative techniques: (i) local perivascular neurotomy was performed at the origin of the left coronary artery; (ii) the stellate ganglion was removed bilaterally. Evaluation of the neural degeneration pattern led the suggestion that three types of neurons at least exist within the heart: (i) neurons innervating the coronary vessels both in the ventricles and in the atria; (ii) neurons innervating the ventricular myocardium, and (iii) neurons innervating the atrial myocardium. The post-ganglionic fibres of the stellate ganglion innervate the vessels of the whole heart. Their contribution to the innervation of the ventricular myocardium represents about 30%.
Freeze-fracture and thin-section study of condensing vacuoles in rat pancreatic acinar cells
Authors: Sesso A. , Assis Paula , Kuwajima V.Y. , Kachar B.
Published: July 2008

Early and late developmental forms of condensing vacuoles are prominent in the relatively low rate secreting acinar cells of suckling rat pancreas. These vacuoles, when studied in freeze-fracture replicas and ultrathin sections under standard processing conditions, showed a biphasic evolution. During the first stage the condensing vacuoles (referred to as CVj) enlarge, accumulating contents of rather low electron density. Fracture faces with irregular patterns, possibly the result of fusion (pinching off) of microvesicles with (from) the condensing vacuoles, were occasionally encountered. The infrequency of such images indicates that fusion-fission during the growth stage must be a very rapid event. One common type of surface irregularity is gibbosities (or convexities) in the P fracture face with complementary images in the E fracture face. The significance of these irregularities, which are in apparent discordance with the theory of microvesicular transport, is unclear. By the end of the growing period the condensing vacuoles are large and smooth-surfaced (referred to as CV2) with contents of intermediate electron density (between that of the initial growing stage and that of the mature zymogen granule). The number of intercalated particles on both the large irregularly surfacec CV1·) and large smooth-surfaced condensing vacuoles (CV2) membranes is high and comparable to that of the Golgi saccule and endoplasmic reticulum membranes. During the second stage, the smooth-surfaced condensing vacuoles undergo volume reduction associated with progressive increase in the electron density of their contents, thus becoming zymogen granules. Concomitant with size reduction, the number of intercalated particles in the membranes with CV2 diminishes markedly. The process of membrane retrieval appears to be accomplished selectively by pinching off coated microvesicles heavily studded with intercalated particles.
Myelinated Nerve Fibers in the Parathyroid Gland of the Dog: A Light and Electron-Microscopic Study
Authors: Atwal Onkar S.
Published: July 2008

The distribution of myelinated and non-myelinated nerve fibers in the parathyroid glands of the dog was studied by light and electron microscopy. The mixed fasciculi with myelinated nerve fibers (average diameter 7.0 µm) and unmyelinated fibers were present independent of the adventitia of the arterioles. The mixed fasciculi were accompanied by large amounts of collagen fibrils running in the direction of the nerve fibers. The fasciculi were surrounded by a complete sleeve composed of a perineural epithelial sheath which a basal lamina on both sides. The possibility that these fibers might represent an afferent pathway is discussed.
Fine Structure of the Fully Keratinized Hair Cuticle in the Head Hair of the Human
Authors: Muto H. , Ozeki N. , Yoshioka I.
Published: July 2008

The cuticle is composed of five cell layers in the cross section of the hair at a level of 100 mm above the scalp. Intercellular junctions between two cuticular cells are zonulae occludentes (tight junction); they consist of five layers. The gap junctions of the intercellular communications occur near the cortex. The trichohyalin granule appears in the cuticular cells of completely cornified head hair. The granule is generally smaller than that of the keratohyalin granule, and spherical in shape. The granule is not visible in the area near the surface of the hair. The keratin in the cytoplasm of the cuticular cell may originate from the trichohyalin granule.
Electron Microscopic Study of the Sarcolemma of Parkinje Cells of the Goat Heart
Authors: Núñez-Durán Harol
Published: July 2008

Three portions were characterized in the sarcolemma of Purkinje cells of the goat heart. These portions, i.e., intercalated disk, internal and surface sarcolemmal portion, show specific and distinctive characteristics. The surface density of both sarcoplasmic reticulum dyads and intercellular junctions were estimated in these three sarcolemmal portions. Dyads occupy 8,1.6 and 0.3%, respectively, of the area of internal, intercalated disk, and surface sarcolemmal portions. Fasciae and maculae adherentes are 17 and 5% of the intercalated disk and the internal sarcolemma, respectively. The nexal area in the intercalated disk is twice that in the internal sarcolemma. These results are discussed in relation to the excitation-contraction coupling phenomenon and to conduction velocity.
Ultrastructure of the Pancreas of Bradypus tridactylus
Authors: Abrahamsohn P. , Pallot D.J. , Pinheiro P.B.N. , Coutinho V.B. , Pessoa R.G. , Coutinho H.B.
Published: July 2008

The fine structure of the pancreas of the South American three toed sloth, Bradypus trídactylus, is described. In exocrine cells two types of granules are found. The first variety of granules is circular, of about 0.9 µm mean diameter, and probably represents zymogen granules. The second type of granule is larger (up to 1.4 µm in diameter) and contains a granular electron-dense material which is separated from the limiting membrane by a wide space. Only one type of islet cell was found. It contains spherical membrane-bound granules of uniform size.
Decrease of Collagen Content in the Intraocular Fluid of Senile Rats
Authors: Shimizu Kiyoshi , Furuya Tetsuo , Takeo Yuji , Shirama Kazuhiko , Maekawa Kyutaro
Published: July 2008

The total hydroxyproline content in the intraocular fluid (vitreous body and aqueous chamber) of male rats clearly showed the same level throughout the developmental period; during the senile period, however, it remarkably decreased.
Immunofluorescence of Dopamine-Beta-Hydroxylase in Small Intensely Fluorescent Cells of Human Sympathetic Ganglia
Authors: Schröder Hannsjörg , Gerold Norbert , Heym Christine
Published: July 2008

Thoracic and lumbar sympathetic ganglia of human males were investigated using a method for the consecutive demonstration of catecholamines and catecholamine-synthesizing enzymes in fluorescence microscopy. In the thoracic ganglion, a minor population of small intensely fluorescent (SIF) cells, identified by glyoxylic-acid-induced fluorescence, exhibited positive indirect immunofluorescence after incubation with antibody to dopamine-β-hydroxylase (DBH). SIF cells in the lumbar ganglion exclusively stained DBH-negative. The findings indicate the presence of two SIF cell populations in the thoracic ganglia of the human sympathetic trunk, one containing dopamine and the other containing norepinephrine and/or epinephrine. In lumbar ganglia, only dopamine-storing SIF cells appear to be present.
Modulation of Chondrocyte Activity in vitro in Response to Ascorbic Acid
Authors: Hall Brian K.
Published: July 2008

The aim of this study was to examine the response of secondary cartilage to ascorbic acid in vitro. Cells which had not attained the prechondroblast stage when cultured, did not chondrify in vitro, even when exposed to high levels (400 µg/ml) of ascorbic acid. On the other hand, prechondroblasts cultured in the presence of low levels (100 µg/ml) of ascorbic acid did chondrify. Once cytodifferentiation commenced, chondrogenesis was independent of the presence of ascorbic acid in the medium. Cartilage which differentiated in the presence of continuous high levels ( > 200 µg/ml) of ascorbic acid modulated to a tissue which consisted of hypertropic chondrocytes in a highly collagenous extracellular matrix. At the light-microscopic level, this tissue was classified as chondroid bone. At the ultrastructural level, the collagen was seen to be in the form of cross-banded fibres more typical of bone than cartilage. Prelabelling of cultures with either [3H]-thymidine or [3H]-proline showed that neither dedifferentiation of chondrocytes nor the resumption of mitotic activity was responsible for the alterations in the extracellular matrix. The differentiated chondrocytes can secrete an altered extracellular matrix without undergoing cytological dedifferentiation. The role of ascorbic acid in the attainment and maintenance of the differentiated state is briefly discussed.