Prognostic evaluation of branch atheromatous disease in the pons using carotid artery ultrasonography.

BACKGROUND: Branch atheromatous disease is an ischemic stroke, involving occlusion or severe stenosis of the perforating artery, causing neurologic symptoms and serious sequelae. We aimed to investigate initial morphometric and hemodynamic characteristics of the vertebral artery immediately post-onset to predict lesion expanding. METHODS: This case-control study collected demographic, historical, and physical examination data from 44 patients with branch atheromatous disease in the pons at admission. The maximum ischemic pons area and stenosis rate in the basilar artery were calculated using magnetic resonance images. Diameter, velocity, and flow volume of the vertebral arteries were measured using carotid artery ultrasonography. Correlations between ischemic lesion extent and these parameters were investigated. RESULTS: Patients were assigned to groups of less (Group 1) or more (Group 2) than the median maximum ischemic area in the pons, calculated from magnetic resonance images (121.6 mm2). Modified Rankin scale scores were significantly worse in Group 2. Blood pressure and blood findings were similar between groups. Group 2 showed significantly higher basilar artery stenosis rates. Flow volume, velocity, peak systolic velocity, and end-diastolic velocity in the vertebral artery on both sides were significantly decreased in Group 2. CONCLUSIONS: Deteriorated vertebral artery hemodynamics caused a more extensive ischemic lesion in branch atheromatous disease in the pons. Evaluation of the vertebral using carotid artery ultrasonography in the acute phase may be useful for predicting disease progression.

Presynaptic protein Synaptotagmin1 regulates the neuronal polarity and axon differentiation in cultured hippocampal neurons.

BACKGROUND: Hippocampal neurons in the brain polarize to form multiple dendrites and one long axon. The formation of central synapses remains poorly understood. Although several of the intracellular proteins involved in the clustering of central neurotransmitter receptors and ion channels have been identified, the signals involved in pre- and postsynaptic differentiation remain elusive. Synaptotagmin1 is an abundant and important presynaptic vesicle protein that binds Ca(2+) (J Biol Chem 277:7629-7632, 2002) in regulation of synaptic vesicle exocytosis at the synapse. Synapse consists of the formation of synaptic connections and requires precise coordination of Synaptotagmin1. It was reported Synaptotagmin1 plays an important roles in the formation of axonal filopodia and branches in chicken forebrain neurons (Dev Neurobiol 73:27-44, 2013). To determine if Synaptotagmin1 could have a role in formation of axon in hippocampal neurons, we investigated the effects of Synaptotagmin1 overexpression and knockdown using the shRNA on the growth and branching of the axons of primary hippocampal neurons. We showed that overexpression of Synaptotagmin1 leads to abnormal multiple axon formation in cultured rat hippocampal neurons. RESULTS: We first examined the effects of Synaptotagmin1 on the numbers of axon and dendrites. We found that the overexpression of Synaptotagmin1 led to the formation of multiple axons and induced an increase in the number of endogenous postsynaptic protein Homer1c clusters in cultured hippocampal neurons. Endogenous initial segment of axon was detected with anti-sodium channel (anti-NaCh) antibody and with anti-Tau1 (J Neurosci 24: 4605-4613, 2004). The endogenous initial segment of axon was stained with anti-NaCh antibodies and with anti-Tau1 antibodies. Then the numbers of prominence dyed positive were counted as axon. We attempted to specifically knockdown the endogenous Synaptotagmin1 with small hairpin RNAs (shRNAs). To further dissect the functions of endogenous Synaptotagmin1 in neuronal polarity, we used the shRNA of Synaptotagmin1 that specifically blocks the existence of endogenous Synaptotagmin1. When the shRNA of Synaptotagmin1 was introduced to the cells, the number of axons and dendrites did not change. CONCLUSIONS: These results indicate that the accumulation of Synaptotagmin1 may play an important role in axon/dendrite differentiation.

Quantitative analysis of the elastic fiber in the tunica media at the carotid bifurcation.

In this study, the results of our previously reported technique of quantitative analysis by using microscopic image analysis of tissue image slices to calculate the proportion of the area of the tunica media occupied by of elastic fibers was compared with Janzen et al.'s technique at the carotid bifurcation. This particularly analyzed the area of transition between the common carotid and the internal carotid, to observe the quantitative changes in elastic fiber content. The data obtained from our quantitative analysis of elastic fibers were clearly at variance with those obtained by counting the number of elastic fibers. The amount of elastic fibers in the tunica media (the elastic fiber ratio) decreased from the proximal carotid artery (the common carotid) to the bifurcation, then peaked in the internal carotid immediately after the bifurcation before declining again.

Intracranial Bony Canal of the Middle Meningeal Artery - Morphological and Histological Analysis.

The middle meningeal artery (MMA) can play an important role in the surgical revascularization. However, the MMA can be easily injured if it passes through a bony canal. We investigated the morphological and histological features of the bony canal to improve surgical results. MATERIALS AND METHODS: Fifty adult dry skulls were investigated. The length of the bony canal and the distance from the orbital rim to the bony canal were measured. Additionally, 28 cadaveric heads were examined histologically. RESULTS: Sixty-three bony canals were found in 43 skulls. The mean length of bony canals was 9.2 mm, and the mean distance from the orbital rim was 24.0 mm. The bony canal ran mainly from the sphenoid bone (69.8%) to the parietal bone (73.0%). Histologically, both sides of the meningeal grooves gradually closed the distance, and formed the bony canal. The MMA inside the bony canal was enveloped with collagen tissues, divided into branches, and was accompanied by the vein. CONCLUSIONS: The bony canal is located around the pterion and is formed during bone growth. The MMA is covered with collagen tissues inside the bony canal. It is possible to safely expose and preserve the MMA during craniotomy with careful drilling.

Anatomical and surgical evaluation of gastroepiploic artery.

OBJECTIVE: Knowledge of the anatomy of the stomach and its surrounding structures is essential for lymph node dissection. This is the first gross anatomical investigation of anastomosis variations in the gastroepiploic arteries (GEA). The aim of this study is to examine the anastomosis pattern of the right and left GEA (RGEA and LGEA, respectively). METHODS: Seventeen cadavers were dissected, and the anastomotic patterns of RGEA and LGEA were observed macroscopically. RESULTS: The anastomotic patterns were classified into two groups. Type 1 had direct anastomosis (n = 16; 94.1%), whereas Type 2 had no anastomosis (n = 1; 5.9%). Formation of an arterial arch along the greater curvature was observed in twelve cases (70.6%), whereas four cases (23.5%) exhibited mesh-like anastomosis or narrow anastomotic branches. CONCLUSIONS: Direct anastomoses were observed in almost all the cases. These results are significant, and may be useful in the classification of lymph nodes or speculation of cancer metastases.

Development of the human cuneatus medialis nucleus: a morphometric evaluation.

The morphometric features of the development of the human cuneatus medialis nucleus (CMN) were examined using complete serial celloidin sections of 11 brains: nine fetal brains, the brain of a 2-month-old infant and that of a 63-year-old adult. The morphometric analysis revealed at least four stages in the development of the CMN characterized by the maturation of neurons: (1) immature neuronal stage, (2) preparatory stage, (3) accelerated development stage and (4) postnatal stage. The development of the human CMN accelerates after 32 weeks of gestation (WG), and postnatal qualitative maturation also occurs. From the viewpoint of morphometric evaluation, the CMN gradually matures between 18 and 40 WG without a rapid growth phase as far as we have observed.

Aging process of myelinated nerve fibers in the human Lissauer tract.

We calculated numbers and axonal areas of myelinated nerve fibers in the Lissauer tract of the human lumbar spinal cord (L1) from the viewpoint of the aging process. We examined 20 human spinal cords from 13 males and 7 females, age ranging from 41 to 88 years old. We found that, although the number of nerve fibers showed no significant change in relation to the age of the subject, the axonal area of myelinated nerve fiber in the Lissauer tract did decrease with age.

Morphometric difference in the human maxillary nerve fibers between dentulous and edentulous jaw subjects.

This study was conducted to quantify the change in the number and size of myelinated nerve fibers of the maxillary nerve with tooth loss in humans. We carried out a morphometric analysis to compare the number and size of myelinated nerve fibers in the human maxillary nerve between four dentulous and four edentulous jaw cases. Our results indicated that the number of axons decreased by approximately 13,000 with tooth loss. The average size of axons remained unchanged, but there was a change in the fiber size distribution, namely the loss of a large number of small-sized axons was accompanied by the total disappearance of small number of large-sized axons.

Morphometric evaluation of the human tractus solitarius.

We measured the cross-sectional area (CSA) of the human tractus solitarius (HTS) with the help of an image-analyzer system on a cross section of the upper part of the medulla oblongata in 44 Japanese cadavers (22 males and 22 females) and examined the relationship between age, sex and whether the subjects were dentulous or edentulous. The results showed no significant differences between the left and right sides of the HTS in either male or female subjects. However, the size of HTS decreased slightly with age in males but not at all in females, whereas tooth loss had a definite incidence on the size of HTS in females but not in male, as the CSA was smaller in edentulous females but not in edentulous males. This would tend to indicate that a decreases in taste function is connected with the aging process in male, and with tooth loss in females.

Morphometric and quantitative evaluation of the gastroepiploic artery.

BACKGROUND: The gastroepiploic artery (GEA) has been described in various ways by anatomical texts and surgical manuals. Currently, there are no studies that have investigated the thickness and length of GEA using gross anatomical methods. In the present study, we measured the length, circumference, area, and major axis of GEA, and quantitatively evaluated the differences between right and left GEA (RGEA and LGEA), using gross anatomical and morphometric methods for the first time. MATERIALS AND METHOD: Seventeen cadavers were selected. The median age of the cadavers was 82 years. We observed and evaluated GEA with naked eyes, as well as under a stereoscopic microscope. RESULTS: RGEA was significantly longer than LGEA (p < 0.0001). The mean length of RGEA and LGEA were 26.51 ± 5.15 cm and 14.05 ± 3.12 cm, respectively. The mean area of RGEA, LGEA, and the anastomotic point were 3.31 ± 1.71 mm(2), 1.33 ± 1.01 mm(2), and 0.51 ± 0.28 mm(2) respectively. CONCLUSION: RGEA was significantly longer and thicker than LGEA. The results also showed that in almost all of the cases RGEA and LGEA anastomosed with each other and grew thinner as they approached the middle of the greater curvature of the stomach.

The impact of aging on the course of the azygos vein.

INTRODUCTION: The human azygos vein (AV) generally runs on the right side of the vertebral column. However, a shift in its course to the middle/left side of the vertebral column, potentially as a result of aging, has been reported. The aim of this study was to understand the relationship between AV displacement and aging. MATERIALS AND METHODS: Forty-seven adult cadavers were dissected. When an AV left shift was observed, long axis AV length was measured by calculating the number of vertebral bodies under the vein. We also investigated whether a crossover vein existed between AV and hemiazygos vein at the extreme left shifting point, and whether osteophytes existed along the vertebral column. RESULTS: Forty-four cadavers (94%) had left-shifted AVs. A weak positive correlation between age and the length of the left shift was observed (r = 0.3061, P = 0.0364). Thirty cadavers (64%) had crossover veins at the extreme left shifting point, and 24 cadavers (51%) had osteophytes along the vertebral column. There was no significant relationship between the length of left-shifted AVs and the existence of crossover veins or osteophytes. CONCLUSION: The possibility of AV displacement to the left as part of the aging process is suggested.

Development of the human lateral cuneate nucleus: a morphometric evaluation.

The morphometric development of the human lateral cuneate nucleus was examined in nine fetuses and neonates at 18-40 weeks of gestation, a 2-month-old infant and a 63-year-old adult. The authors observed serial sections of the brain containing lateral cuneate nucleus and measured the volume of nuclear column and the number, cell body area and perimeter of neurons using a microscope with a drawing tube and an image-analyzing computer system. A morphometric evaluation revealed that a turning point in the development of the human lateral cuneate nucleus occurring at 30 WG, as this marks the beginning of a gradual increase in the average area and average perimeter; And it is the point at which the neuropil index suddenly increases sharply, to fall back down to lower levels afterwards. The establishment of a neuronal connection between the lateral cuneate nucleus and the cerebellum, which is necessary for proper performance of movements in the upper part of the body.

Morphometric nerve fiber analysis of the human inferior alveolar nerve: lateral asymmetry.

We studied morphometric nerve fiber analysis and the lateral asymmetry of the inferior alveolar nerve (IAN). Human IANs were resected at the mandibular foramen. The preparation of sections involved fixation, washing, dehydration, embedding, sectioning and staining as described in our previous reports. We estimated the average total number of myelinated axons in the right IAN to be 22,808, with an average transverse area of 37.6 microm2, an average perimeter of 23.0 microm, and average circularity ratio of 0.85, with the same measurements in the left IAN being 24,289, 33.9 microm2, 21.6 microm, and 0.86, respectively. Morphological differences between the right and left side were analyzed by applying parametric tests (unpaired t-test) to all measured items. According to these results, the IAN did not demonstrate notable lateral asymmetry in any measured item. We considered that these results were caused by using subjects with the same dentulous condition in both sides.

The aging of human Meissner's corpuscles as evidenced by parallel sectioning.

We examined cross-sectional areas of Meissner's corpuscles to evaluate the changes in their morphology and density that occur during the aging process. Our study of 10 tissue specimens from the right index finger pulp of 10 males, showed that both the size and the number of Meissner's corpuscles decrease with age. We claim greater accuracy in our data thanks to the use of a new sectioning method, namely parallel sectioning of the skin.

Distributions of lesions in hanging suicide brains.

We found a morphological similarity in the distribution of vascular lesions in five hanging suicide brains. The overall findings on the lesions remind us of the venous origin but not of the arterial origin of the blood supply. Morphometric evaluations did not reveal any valuable conclusion. The results of this pathological research may be of clinical importance for the treatment of hanging patients.

Morphometric analysis of the human femoral nerve and its ageing process.

We analysed the sizes of nerve fibres in the human femoral nerve which innervates the quadriceps femoris muscles. The material was taken from 14 cadavers aged from 61 to 97 years. A linear regression analysis disclosed a significant age-related decrease of the mean transverse area of axons. Such decrease with age may be an indication of motoneuron atrophy. Our results could help in the understanding of the correlation between morphology and function during the ageing process.

Age-related changes in nerve fibers of the human fasciculus gracilis.

Nerve fibers of the human fasciculus gracilis were studied on 10 male cadavers aged 41-97 years using a discriminative staining method and a microscopic image-analyzing system. Our data show that the transverse areas of axons in the human fasciculus gracilis significantly decrease with age, while no significant correlation was observed between the number of fibers and age.

Differences in the axonal compositions of the human mandibular nerve between dentulous and edentulous jaws.

We examined the human mandibular nerve to find differences in the composition of nerve fiber axons between dentulous and edentulous jaws Using Goto's modification of Masson-Goldner's method. We discovered that the edentulous jaw did not contain any large size axons, compared with the dentulous jaw. This can be considered as evidence that the larger fibers innervating the periodontal ligament decreased degenerated after tooth loss.

Morphological study of nerve endings in jaw muscles of post-hatching American alligators (Alligator mississippiensis).

Two months after hatching, the fibers of the jaw muscles of the American alligator are associated with three types of nerve terminals namely, plates, simple plates, and grape endings. Simple plate endings are mainly observed on the small muscle fibers. Grape-type endings are found on muscle fibers that resemble the tonic fibers of garter snakes (Hess, Am. J. Anat., '63). Most terminals are plate endings and account for 53.7-74.7% of terminals per muscle. Fibers with grape-type endings were found in all the jaw muscles studied; they lack well organized T-systems, M-lines, and post-junctional sarcolemmal folds, as well as irregularly distributed small of fibrils, and zigzag Z-lines. The properties of nerve endings of the American alligator indicate that M. depressor mandibulae, M. pseudotemporalis, and M. pterygoideus posterior have primary roles in jaw movements. M. pterygoideus anterior and M. intramandibularis contribute mainly to postural adjustments of the jaws. The multiplicity of nerve terminals in the jaw muscles of American alligators contrasts with the simple movements of their jaws. © 1994 Wiley-Liss, Inc.

Distribution of calcium-ATPase in developing teeth of embryonic American alligators (Alligator mississippiensis).

Light microscopic and ultrastructural observations were carried out to evaluate the cell morphology and histochemistry (calcium-ATPase activity) of developing teeth in embryonic American alligators (Alligator mississippiensis). Ca-ATPase activity was observed in the distal and lateral cell membranes, rough endoplasmic reticulum (rER), mitochondria, vacuoles, and other organelles of the ameloblast, but only in the distal cell membrane and process of the odontoblast. Enzyme activity in the ameloblasts increased gradually during development. These sites of enzyme activity are related to mineralization of the enamel layer, similar to that in mammalian tooth development. Alligator teeth are heavily mineralized like mammalian teeth; however, alligator ameloblasts have undeveloped distal processes during mineralization in contrast to mammalian ameloblasts in which Tomes' processes are found near the distal portion of ameloblasts at maturation stage. The localization of intense enzyme activity in the distal and lateral ameloblast cell membrane suggests that these regions are the site of accumulation of calcium as enamel differentiates in the developing tooth. © 1993 Wiley-Liss, Inc.