Average Transverse Area Research Articles

Effects of Atractylodes macrocephala rhizoma on isoproterenol-induced myocardial hypertrophy in mice

Background: The studies about the protective effect on the heart of single Atractylodes macrocephala rhizoma (AMR) herb and mechanisms have not been reported. Objective: The purpose of this study was to assess the effects of AMR on attenuating myocardial hypertrophy induced by isoproterenol (ISO) in mice. Materials and Methods: Mice were randomly divided into normal control group, ISO control group, ISO plus metoprolol (60 mg/kg) group, ISO plus AMR (2, 4, and 8 g/kg) groups, and AMR (4 g/kg) control group. The mice with myocardial hypertrophy were established by subcutaneous (s.c.) injection with ISO (2 mg/kg/d) and administered intragastrically with the corresponding drugs in the volume of 0.2 mL/10 g/d for 7 days. In the normal and AMR control groups, mice were injected (s.c.) with physiological saline (the solvent for ISO) and administered intragastrically with drinking water for 7 days. Results: Compared with the ISO-induced group, AMR significantly decreased heart weight index, left ventricular weight index, and average transverse area of cardiomyocytes, significantly increased the activity of total superoxide dismutase in serum and the level of the angiotensin II receptor type (AT) gene expression in myocardium and significantly decreased the contents of malondialdehyde, cyclic adenosine monophosphate , and aldosterone in serum and angiotensin II (Ang II) in myocardium. Conclusion: The ability of AMR to mitigate myocardial hypertrophy is partly associated with its anti-oxidative effect, restraining excessive secretion or activation of neuroendocrine factors, and the stronger upward effect on AT2gene expression than AT1.

Sex differences in morphometric aspects ofthe peripheral nerves and related diseases.

BACKGROUND: The elucidation of the relationship between the morphology of the peripheral nerves and the diseases would be valuable in developing new medical treatments on the assumption that characteristics of the peripheral nerves in females are different from those in males.METHODS: We used 13 kinds of the peripheral nerve. The materials were obtained from 10 Japanese female and male cadavers. We performed a morphometric analysis of nerve fibers. We estimated the total number of myelinated axons, and calculated the average transverse area and average circularity ratio of myelinated axons in the peripheral nerves.RESULTS: There was no statistically significant difference in the total number, average transverse area, or average circularity ratio of myelinated axons between the female and male specimens except for the total number of myelinated axons in the vestibular nerve and the average circularity ratio of myelinated axons in the vagus nerve.CONCLUSIONS: The lower number of myelinated axons in the female vestibular nerve may be one of the reasons why vestibular disorders have a female preponderance. Moreover, the higher average circularity ratio of myelinated axons in the male vagus nerve may be one reason why vagus nerve activity to modulate pain has a male preponderance.

Morphometric aspects of the facial and skeletal muscles in fetuses

ObjectivesThere are few research reports providing a comparison of the muscle fiber morphometry between human fetuses and adults. Data on fetal and adult muscle fibers would be valuable in understanding muscle development and a variety of muscle diseases. This study investigated human muscle fiber growth to clarify the difference between the facial muscles and other skeletal muscles. MethodsThe materials were obtained from three male fetuses (6-month-old) and 11 Japanese male cadavers aged 43–86 years (average: 71.8). Human buccinator muscles (facial muscles), masseter and biceps brachii muscles (skeletal muscles) were resected. We counted the muscle fibers and measured their transverse area. We also calculated the number of muscle fibers per mm2 (NMF) and the average transverse area of the muscle fibers (TAMFs). ResultsThe average of the NMF of the buccinator, masseter and biceps brachii muscles in fetuses had, respectively, 19, 37, and 22 times as many fibers as those in adults. The average fetus/adult ratios of the TAMF of the buccinator, masseter and biceps brachii muscles were 4.0%, 2.4%, 4.1%, respectively. ConclusionsThe average NMF for all kinds of muscles decreased after birth; however, the peak in life-span or decreases with the aging process tended to vary with the kind of muscles examined. The average TAMF for all kinds of muscles enlarged after birth. We considered that the enlargement of the TAMF was connected with the emergence of fetal movements and functional demands after birth.

The relationship between Bell’s palsy and morphometric aspects of the facial nerve

Epidemiological data of Bell's palsy (BP) have been reported. For example, the annual incidence of BP is 15-30 per 100,000 persons, with equal numbers of men and women affected, and there is no predilection for either side of the face. However, details of the relationship between BP and morphometric aspects of the facial nerve have not been available in textbooks. We performed a morphometric analysis of human facial nerve fibers and estimated the total number of myelinated axons (TN) and average transverse area of myelinated axons (ATA). The facial nerve showed a significant decrease of TN with increasing age (r = -0.77; p < 0.01), but showed no significant changes of ATA with age (r = -0.01; p = 0.96). We supposed that the TN decrease with age was a factor in the delayed recovery from BP seen in the elderly. Moreover, the TN and ATA showed no significant differences between female and male specimens (p < 0.05), or between the right and left side specimens (p < 0.05). Our present results seem to explain the absence of significant sex and affected side differences in BP.

3D In Vivo optical coherence tomography based on a low-voltage, large-scan-range 2D MEMS mirror

3D in vivo optical imaging on a mouse has been obtained using a 2D MEMS mirror for lateral scanning in a time-domain optical coherence tomography (OCT) system. The MEMS mirror aperture size is 1 x 1 mm(2), and the device footprint is 2 x 2 mm(2). The MEMS mirror scans +/- 30 degrees optical angles about both x and y-axis at only 5.5V DC voltage. An endoscopic probe with an outer diameter of 5.8 mm has been designed, manufactured and packaged. The probe scans an average transverse area of 2 mm x 2 mm. The imaging speed of the probe is about 2.5 frames per second, limited by the speed of the employed optical delay line.

RESULTS FROM THE UCLA/FNPL UNDERDENSE PLASMA LENS EXPERIMENT

A gaussian underdense plasma lens with peak density 5 × 1012 cm −3 and a full width half maximum (FWHM) length of 2.2 cm has been used to focus a relativistic electron beam. This plasma lens is equivalent in strength to a quadrupole magnet with a 150 T/m field gradient. The lens focused a 15 MeV, 16 nC electron beam with initial dimensions σx,y ≈ 650 μ m and σz ≈ 6.5 mm onto an optical transition radiation (OTR) screen ~2 cm downstream of the lens. The average transverse area of the plasma focused electron beam was typically demagnified by a factor of 23. The evolution of the beam envelope in the area near the beam waist was measured for both round beams and asymmetric beams with x:y aspect ratios as large as 1:5. The light from the OTR screen in the round beam case was also imaged into a streak camera in order to directly measure the correlation between z and σr within the beam.

Morphometric aspects of peripheral nerves in adults and the elderly

There have been inconsistencies among reports of age-related differences in human peripheral nerves (PNs). For such studies, normal control values are necessary. Moreover, the diversity of methods employed makes it difficult to compare results. We used the same histological procedures and methods to measure 12 PNs: 8 in the cranial nerves, 2 motor nerves in the lower limb, and 2 nerves in the autonomic system. We performed a morphometric analysis of nerve fibers and estimated the change in the total number (TN) and average transverse area (ATA) of myelinated axons from adulthood to old age. The spinal nerves demonstrated notable age-related changes in TN and ATA. Most of the cranial nerves also demonstrated notable age-related changes in TN and ATA. However, some nerves demonstrated no such age-related changes and were affected more by other factors. With regards to the autonomic nerves, the lesser splanchnic nerve indicated age-related changes in TN, but the greater splanchnic nerve indicated no age-related changes in either TN or ATA. The autonomic nerves were affected not only by the aging process but also by the pathological changes to the peripheral tissues that they innervate.

Morphometric Analysis of the Inferior Alveolar Nerve Fails to Demonstrate Sexual Dimorphism

With regard to the incidence of inferior alveolar nerve (IAN) damage after an IAN block or following oral and maxillofacial surgical procedures, there are reports of sexual dimorphism, no sexual dimorphism, and little sexual dimorphism. However, details of the morphology and sexual dimorphism in the characteristics of the IAN have not been available in textbooks. We morphometrically analyzed the human IAN and clarified these issues. The materials were obtained from 22 cadavers (11 female and 11 male), aged 59 to 84 years (average age: 74.1 yr), and dentulous. The causes of death did not influence the nervous system, so the IANs were considered to be normal. Human IANs were resected at the mandibular foramen. We counted the myelinated axons and measured the transverse area, perimeter, and circularity ratio of the myelinated axons. We estimated the average total number of myelinated axons in the female IAN to be 25,230, with an average transverse area of 34.1 microm(2), an average perimeter of 21.8 microm, and an average circularity ratio of 0.86, with the same measurements in the male IAN being 20,278, 31.7 microm(2), 20.7 microm, and 0.87, respectively. Our data showed no significant difference between the female and male specimens in any measured item (P < .05). We assumed that the sex difference in the incidence of IAN damage was not affected by the morphometric findings. Our findings might partly explain why there is no significant sex difference in the incidence of IAN damage.

Morphometric analysis of fibers of the human vestibular nerve: sex differences

The aim of this study was to analyze myelinated axons in the human vestibular nerve (VN). We assumed that a smaller total number and average transverse area of myelinated axons in the female than male VN, would partly explain the female preponderance of vestibular disorders. The materials were obtained from 24 cadavers (12 females and 12 males) aged 54-90 years (average 74.8 years). We counted the myelinated axons, measured the transverse area of the myelinated axons, and analyzed morphological differences between the female and male specimens. The total number differed significantly between the female and male specimens. The older generation of both sexes tended to have lower total counts, but there was no significant difference among the generations. The average transverse area of the myelinated axons did not differ significantly between the female and male specimens. The older generation of both sexes tended to have a smaller average transverse area, and there was a significant difference among the generations. The presented results indicated that the lower total number, not the average transverse area, of myelinated axons in the female VN might be one of the reasons why vestibular disorders have a female preponderance.

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.

Microstructure evolution of Ni, Cr, Al–TaC in situ composite directionally solidified under a high temperature gradient

The effect of solidification rate on the solidified structure, solute segregation and microstructures such as TaC rods volume fraction, TaC rods average spacing, TaC average transverse area and γ′ phase were experimentally investigated under a high temperature gradient by employing a method of directional solidification with liquid metal cooling. Three types of the solidified structure were identified: planar, cellular and dendritic. Both solidified structure and solidification rate had an effect on the eutectic morphologies. The TaC rods volume fraction could be changed with increasing solidification rate. TaC average inter-rods spacing and TaC average transverse areas decreased, the PS (parameter of shape) of γ′ tends to one and the size of γ′ phase decreased with increasing solidification rate.

Morphometric nerve fiber analysis and aging process of the human vestibular nerve.

Myelinated and unmyelinated nerve fibers of the human vestibular nerve were analyzed with the use of a new staining method that makes it possible to discriminate various structures of the nervous tissue. An image-analyzing digitizer, a microscope with a drawing tube and a personal computer for storing data and performing statistical analyses were employed in this study. We measured the axonal numbers and transverse areas of myelinated vestibular nerve fibers in 20 cadavers, and of unmyelinated fibers in 14 cadavers. The average number of myelinated axons and unmyelinated axons were 20,318 and 2,782, and the average transverse area of their axons were 3.46 and 0.49 micron 2, respectively. The transverse areas of myelinated axons decreased with age, although the numbers of their axons did not change. However, in the case of unmyelinated axons, both the transverse areas and the numbers did not change.

Morphometric Analyses of Axons in the Lateral Corticospinal Tract with Ageing Process

Morphometric analyses were carried out to reveal a relation between age and axonal changes in the lateral corticospinal tract (LCST) at the L1 level of the human spinal cord. Histological preparations of the spinal cord were made after embedding in celloidin to stain with Luxol fast blue-periodic acid-Schiff-hematoxylin or Klüver-Barrera methods. The number, average transverse area, total area and diameter of axons of the LCST were counted and measured using an image-analyser combined with a computer. The morphometric analyses revealed that (1) there was a significant decrease in the axonal number of the LCST with age (p < 0.001); (2) the axons were not partially nor completely accompanied by surrounding myelin sheaths, and increased in number with age; (3) the diameter and average area of axons in the LCST became significantly reduced with age (p < 0.01); (4) the total area decreased significantly with age in a unit area of 2,700 microns2; and (5) the circularity ratio showed no significant change with age.

Microscopic morphometry of the spinal cord with cervical spondylotic myelopathy

Quantitative studies with morphometric assessments were carried out on the slpinal cord of four cases (aged 71–88 years) with cervical spondylotic myelopathy (CSM), and compared with four normal spinal cords from age‐matched cadaver specimens (aged 76–84 years). The histological preparation of the slpinal cord was made after embedding in celloidin and staining with luxol fast blue‐periodic acid‐Schiff‐hematoxylin and Klüver‐Barrera methods. the number, average transverse area and perimeter of the anterior horn cells (AHC) in the Rexed's lamina IX at C3, C5, C6 and L1 levels were counted and measured; the number, average transverse area and perimeter of axon in the posterior funiculus at C3 level and in the lateral corticospinal tracts at L1 level were also counted and measured under high magnification with oil immersion (1340 times), using a combination of an electronic optical planimeter, a microscope with a drawing tube, and a personal computer. The results can be summarized as: (i) The numbers of AHC in CSM at C5, C6 and L1 levels were significantly decreased compared with normal controls, and the average transverse area of AHC at C6 and L1 levels showed a decrease in varying degrees (p&lt;0.05 or P&lt;0.01, respectively). However, the number and average area of AHC in CSM at C3 level did not show any difference. (ii) The number and average transverse area of axons in the posterior funiculus with CSM at C3 level showed a significant reduction compared with normal controls (P&lt;0.01 and P&lt;0.05, respectively). (iii) There was an obvious decrease in the number of axons in the lateral corticospinal tracts of CSM at L1 level (P&lt;0.01), but the average area of axons showed no statistical reduction. It can be deduced from these results that there were ascending degeneration of the posterior funciculus and descending degeneration of the lateral corticospinal tracts above and below the segments of comparession caused by CSM. The loss in number and reduction in transverse area of AHC mainly occurred in those segments involved with compression. However, the result of AHC at L1 level revealed that CSM may have a distal influence on AHC below thesegments of compression.