• Korean Journal of Veterinary Research
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• v.60 no.3
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• pp.139-144
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• 2020

Ten cadavers were studied to compare the accessibility of cervical vertebral canal with conventional standard ventral slot and modified slanted ventral slot. One group performed standard ventral slot procedures at the C3-4, C5-6. The other group performed modified slanted ventral slot with inverted cone technique procedures at the C3-4, C5-6 computed tomography was performed before and after surgery. The accessibility of cervical vertebral canal with conventional standard ventral slot and modified slanted ventral slot using computed tomography in C3-4 and C5-6 intervertebral space was compared. Although smaller ostectomy was performed in the modified slanted ventral slot, some lesions were more accessible but limitations were obvious in C3-4 and C5-6 intervertebral disk space. After the disc material has been identified through accurate preoperative diagnostic imaging, less morbidity and complications can be expected if the appropriate surgical method is selected based on the lesion of compression.

• The Korean Journal of Physiology
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• v.30 no.1
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• pp.117-124
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• 1996

This study evaluated the hypothesis that motoneuron collaterals modulate the excitability of ventral spinocerebellar tract neurons. In acute cats, 128 ventral cerebellar tract cells were studied extracellularly to determine the effects of ventral root stimuli. The majority of the cells responded to ventral root stimulation with either short or long latency increases in spike discharge. In many cells with sufficient spontaneous activity ventral root stimulation also evoked a long lasting reduction in activity. In preparations with the dorsal root ganglion removed VSCT neurons had similar response properties. In some cells contralateral ventral root stimulation also evoked excitatory responses. These findings indicate the VSCT can provide the cerebellum with information regarding activity in the final output neurons of the motor system, the alpha motoneurons.

• The Korean Journal of Pain
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• v.19 no.2
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• pp.175-180
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• 2006

Background: A transforaminal epidural steroid injection has been used for the treatment of radicular arm or leg pain, which has the advantage of ventral epidural spreading compared to either an interlaminar or caudal approach. However, several factors are known to affect the epidural spread pattern of contrast dye; therefore, the injected medication can not be delivered to the target site. The objective of our study was to observe any differences in the contrast flow patterns according to several factors. Methods: A total of 34 epidurographies in 29 patients, who underwent fluoroscopically guided transforaminal epidural steroid injections, were evaluated. After confirming the location of the needle tip within the anterior superior aspect of the neural foramen in the lateral view, and at the 6 o'clock position to the pedicle in the anteroposterior view, 2 ml of contrast dye was injected. The contrast flow patterns of ventral, ventral and dorsal, and dorsal epidural filling were analyzed, according to age, gender, magnetic resonance imaging finding and history of previous back surgery. Results: Ventral contrast flow occurred in 30 out of the 34 epidurographies (88%). Both ventral and dorsal contrast flow patterns were observed 13 out of 16 (81%) patients in the older age group. Also, both ventral and dorsal contrast flow patterns were observed in 16 out of 18 (88%) patients with spinal stenosis. Conclusions: Transforaminal epidural steroid injections, performed uner fluoroscopy, provide excellent nerve root filling and ventral epidural spreading. Patients with spinal stenosis or an old age have both ventral and dorsal epidural spreading patterns.

• Animal cells and systems
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• v.7 no.3
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• pp.237-248
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• 2003

Recent evidence on behaviors in macaque monkeys indicate that the medial temporal cortical areas such as the entorhinal cortex (EC), perirhinal cortex, and parahippocampal cortex (PHC) are importantly involved in limbic and sensory memory function. Neuroanatomical studies also have demonstrated that the medial temporal cortical areas are connected with the ventral striatum, although comparatively little is known about the precise topography of these connections. We investigated the topographic organization of connections between the medial temporal cortical areas and the ventral striatum by placing retrograde tracers into five different regions of the ventral striatum: the ventromedial caudate nucleus, ventral shell, central shell, dorsal core of the nucleus accumbens (NA), and ventrolateral putamen. We found that the shell of the NA was the main projection site from the medial temporal cortical areas. Within the shell of the NA, there were also differential connections: EC diffusely innervates shell of the NA, while the projections from the perirhinal cortex and PHC concentrate on the ventral shell of the NA. Taken together, it is possible that the ventral shell of the NA is the main integration site of the limbic and sensory memory coming from the EC, perirhinal cortex, and PHC.

• Animal cells and systems
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• v.10 no.3
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• pp.137-143
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• 2006

A series of no-choice olfactory response tests using water pre-conditioned with females, with intact and surgically removed ventral glands, at various reproductive states were conducted to determine whether male Hynobius leechii discriminates among females in different reproductive states based on chemical cues. Similarly, ventral gland extracts were tested, and ventral glands were examined histologically. Males’ responses to putative odors of females in four (ovulating, ovulated, ovipositing, and oviposited) reproductive states were independently measured by: i) the latency time to initiate male behavioral response, ii) the arrival time at a fixed point of putative odor source, and iii) the staying time close to the odor point source. Male salamanders showed significant olfactory responses to recently ovulated and ovipositing female odors by quickly arriving at odor sources and staying longer at the origin of the source, but the olfactory responses to the earlier staged ovulating females and the later stage of already oviposited females were not different from controls. Olfactory responses of test males to water preconditioned by intact females or females with ventral glands excised were not different. In addition, ventral gland extracts did not induce significant olfactory responses of test males although the lumens of alveoli in ventral glands of oviposited females were smaller than those of ovulated females. These results indicate that male H. leechii recognizes ovulated and ovipositing females based on chemical cues released but not from the ventral glands.

• The Korean Journal of Physiology
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• v.21 no.1
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• pp.59-66
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• 1987

This study was aimed to investigate whether the conduction velocity of nerve impulses through the ventral afferent fibers is constant along their entire courses in dorsal as well as in ventral roots. Cats were anesthetized with ${\alpha}-chloralose$ (60 mg/kg, i.p.) and artificially ventilated. Laminectomies were done on L4-S1 spinal vertebrae to expose the lumbosacral spiral cord. Both ventral and dorsal roots of L7 or S1 spinal segments were isolated and cut near the spinal cord. Ventral roots were placed on 6-lead stimulating electrodes and stimulated with supra C-threshold intensity. Divided dorsal root fascicles were placed on bipolar recording electrodes and single fiber units activated by the stimulation of the ventral roots were identified. Followings are the results obtained: 1) A total of 27 VRA units were identified. 10 units of them conducted impulses slower than 2 m/sec. Conduction velocities of the remaining units were in the range of 3.11-20.91 m/sec. 2) In 12 Units conduction velocities Of the VRA units through dorsal$(CV_{DR})$ and venral root$(CV_{DR})$ were determined respectively. There was a tendency to conduct impulses faster through dorsal roots$(CV_{DR}=8.19{\pm}3.26\;m/sec)$ than ventral roots$(CV_{DR}=3.46{\pm}1.02\;m/sec)$. From the above results we confirmed that there exist nerve fibers in continuity between the spinal ventral and dorsal roots but we could not ascertain whether there is a change in conduction velocity through the entire course of ventral afferent unit.

• Animal cells and systems
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• v.7 no.4
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• pp.317-325
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• 2003

Corticostriatal connections of auditory areas within the rostral and caudal portions of the superior temporal gyrus (STG) and in the supratemporal plane(STP) of pigtail macaque (Macacca nemestrina) were studied with particular emphasis on specific projections to the ventral striatum. Retrograde tracers were Injected into five different regions of the ventral striatum such as the ventromedial caudate nucleus, ventral shell, central shell, dorsal core of the nucleus accumbens (NA), and ventrolateral putamen to Identify the cells of origin. There were only few projections from the auditory areas in the STP to the ventral striatum. However, the association (or belt) areas of the STG collectively had widespread corticostriatal projections characterized by differential topographic distributions. The rostral parts of the STG strongly projected to the ventromedial caudate nucleus. The midportion of the STG also projected to the same ventral striatal regions, but the connections were relatively less extensive. Interestingly, the caudal portion of the STG had no connection to all subregions of the ventral striatum. These differential patterns of corticostriatal connectivity suggest that the ventromedial caudate nucleus would be a major auditory convergence area and mainly involved in sound recognition rather than spatial localization of sound sources.

• Animal cells and systems
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• v.8 no.4
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• pp.319-328
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• 2004

Extrinsic connections between the cortex of the superior temporal sulcus (STS) and the ventral striatum in pigtail macaque monkeys (Macacca nemestrina) were studied by injection of retrograde tracers into the ventromedial caudate nucleus, the ventral and central shells of the nucleus accumbens (NA), the dorsal core of the NA, and the ventrolateral putamen. In the present study, we demonstrate that the projections from the unimodal (area TAa, IPa, TEa, and TEm) and the multimodal (area TPO and PGa) sensory association areas in the STS mainly terminate in the ventromedial caudate nucleus as well as in the ventral and central shells of the NA. However, there are only few projections to the dorsal core of the NA and the ventrolateral putamen from the sensory association cortex in the STS. Based on these differential neural connections between the subterritories of the ventral striatum and the sensory association areas, the ventromedial caudate nucleus and the shells of NA appear to be major integration sites for sensory input from the STS and functionally different from the dorsal core of NA and the ventrolateral putamen.

• BMB Reports
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• v.49 no.10
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• pp.572-577
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• 2016

The short gastrulation (sog) shadow enhancer directs early and late sog expression in the neurogenic ectoderm and the ventral midline of the developing Drosophila embryo, respectively. Here, evidence is presented that the sog primary enhancer also has both activities, with the late enhancer activity dependent on the early activity. Computational analyses showed that the sog primary enhancer contains five Dorsal (Dl)-, four Zelda (Zld)-, three Bicoid (Bcd)-, and no Single-minded (Sim)-binding sites. In contrast to many ventral midline enhancers, the primary enhancer can direct lacZ expression in the ventral midline as well as in the neurogenic ectoderm without a canonical Simbinding site. Intriguingly, the impaired transcriptional synergy between Dl and either Zld or Bcd led to aberrant and abolished lacZ expression in the neurogenic ectoderm and in the ventral midline, respectively. These findings suggest that the two enhancer activities of the sog primary enhancer are functionally consolidated and geographically inseparable.

• Parasites, Hosts and Diseases
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• v.24 no.1
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• pp.63-70
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• 1986

The tegumental ultrastructures oi Echinostoma hortense adults were observed by scanning electron microscopy. The worms of 4 weeks of age were harvested from albino rats experimentally infected with the metacercariae obtained from the loach. The results were as follows: 1. The worms were leaf-like and their anterior end portion, including oral sucker and head crown, ventrally curved to face posteriorly. The tegument of whole body was wrinkled transversely and covered with cobblestone-like cytoplasmic processes. 2. The oral sucker had roundly swollen (type I ) sensory papillae on the ventral half of its lip and mini-ciliated knob-like (type I ) sensory papillae, arranged in 2∼3 rows, on the dorsal outer surface. 3. Aspinous ventral sucker had many of type I papillae arranged in a circular band on its outer surface. The tegument around the genital opening was of similar feature to the ventral sucker, but sensory papillae were hardly found around the former. 4. Scale-like spines with broad base and round tip were distributed densely on the tegument anterior to the ventral sucker but they became sparse in posterior half of the ventral surface, finally to disappear at posterior extremity. A few number of type I papillae were observed on the ventral surface. The results suggest that the tegument of 5. hortense is similar to that of other echinostomes etapecially 5. revolutum. But the number and arrangement of collar spines, and/or the type and distribution of sensory papillae seem characteristic features of E. hortense differed from other echinostomes.