Comparisons of endocranial casts of the subfamily Hydrodamalinae (Mammalia; Sirenia) reveal some interesting evolutionary trends, especially in the changes to the shape of the cerebrum and olfactory bulbs, and the position of the optic nerve. Endocranial casts of both Hydrodamalis spissa Furusawa, 1988 and H. gigas (Zimmermann, 1780) reveal several synapomorphies (spherical olfactory bulbs, the optic nerve separate from the trigeminal nerve, and diminished fissura longitudinalis cerebri and ). A revised phylogeny of North Pacific Sirenia based in part on endocranial casts demonstrates that H. spissa and H. gigas are very closely related within the Hydrodamalinae. On the other hand, although they contemporaneously inhabited the North Pacific Ocean, the eastern Pacific H. cuestae differs clearly from the western Pacific H. spissa.

抄録全体を表示

Albert Einstein's brain has long been an object of fascination to both neuroscience specialists and the general public. However, without records of advanced neuro-imaging of his brain, conclusions regarding Einstein's extraordinary cognitive capabilities can only be drawn based on the unique external features of his brain and through comparison of the external features with those of other human brain samples. The recent discovery of 14 previously unpublished photographs of Einstein's brain taken at unconventional angles by Dr. Thomas Stoltz Harvey, the pathologist, ignited a renewed frenzy about clues to explain Einstein's genius. Dr. Dean Falk and her colleagues, in their landmark paper published in Brain (2013; 136:1304-1327), described in such details about the unusual features of Einstein's brain, which shed new light on Einstein's intelligence. In this article, we ask what are the unique structures of his brain? What can we learn from this new information? Can we really explain his extraordinary cognitive capabilities based on these unique brain structures? We conclude that studying the brain of a remarkable person like Albert Einstein indeed provides us a better example to comprehensively appreciate the relationship between brain structures and advanced cognitive functions. However, caution must be exercised so as not to over-interpret his intelligence solely based on the understanding of the surface structures of his brain.

抄録全体を表示

The morphometric anatomy of the superficial cerebral veins in relation to cerebral gyri was studied in 244 cadaveric cerebral hemispheres. Our morphometry revealed that the position of the central and that of the parieto- near the superior sagittal sinus were at 55% and 83.6% respectively of the half-perimeter running from the frontal pole to the pole (FO) . The drainage position of the central sulcal vein (of Rolando) into the superior sagittal sinus was about 65% of the FO half-perimeter on each side. The three main drainage veins among the superficial cerebral veins are classified into four types: (1) left predominant, (2) right predominant, (3) no laterality, and (4) absent. No laterality predominance was observed regarding the superficial middle cerebral vein (of Sylvius) . The inferior anastomotic vein (of Labbe), however, was predominant on the left hemisphere. The superior anastomotic vein (of Trolard) was observed with similar frequency in each type. In conclusion, the superficial cerebral veins can be classified into eight different types according to venous drainages.

抄録全体を表示

We measured the lengths of some parts of the right and left hemispheres (HEs) in 70 formalin-fixed brains and on 15 computed tomography/magnetic resonance imaging (CT/MRI) images (7 left-handed and 8 right-handed cases) to clarify the morphological changes indicating which HE developed earlier and handedness. In many cases of the fixed brains, 1) the distance from the frontal pole to the

pole was longer in the left HE than in the right HE, 2) the distance from the middle plane to the lateral-most portion of the HE was wider in the right HE than in the left HE, 3) the left pole elongated more posteriorly and covered the right pole, and 4) the volume of each HE was nearly the same. The results indicate that the left HE develops and grows slightly earlier in the larger semi-cranium (half of the cranium) than the right HE which develops later in the smaller semi-cranium. The whole brain was more spherical in the female cases than in the male cases. The morphological changes in both HEs for handedness were not evident on the CT/MRI images.

抄録全体を表示

1. The lunate is present in 69 Japanese brains among 90, in 101 hemispheres among 180; the percentage is 76.7 for individuals, 56.1 for hemispheres.
2. As for the side of the appearance of the lunate, the left side (25 among 90 individuals, 27.7%) is far more frequent than the right (12, 13.3%). Among 101 hemispheres with the lunate 57 are left (56.4%), 44 are right (43.5%) As for the sexual difference the lunate is present more frequent in the female brain (17 among 24 hemispheres, 70.8%).
3. The site of the lunate is on the same hight with the pole (66.3%), when it deviates, it is more frequent lower (28.7 %) than higher (5.4%).
4. The form of the lunate is almost half circle in 50.4%(type I-V), the others (type VI-XI) are more flat or bent down, the chord of the arc runs almost always from up and medial to down lateral.
5. The greatest distance from the pol to the lunate is 2.6-3.5cm long in total, it is longer (3.1-3.5cm) by the half circle form, shorter (2.6-3.0cm) by the flat form.
6. The depth of the lunate is pretty deep, it's length is 3.1-5.0cm.
7. The situations of the lunate is up and lateral to the outer part of the retrocalcarine , except this retrocalcarine the upper and lower sulci are surrounded by the arc of the lunate. A part of the upper may situate out of the arc, the lateral comes always lateral and out of the lunate.
8. The retrocalcarine is present in 135 among 180 hemispheres, its prolongation to the lateral side is observed in 88 among 135. The lunate comes in 61 among these 88, the remaining 40 hemispheres with the lunate are without retrocalcarine.
9. As for the anastomosing with lunate the upper is more frequent than the lower . The number of the anastomose is one in 45.5% among lunate hemispheres. The site of the anastomose is at the middle part of the , less frequent at the lower end and scanty at the upper end.
10. The lunate is almost always accompanied by the prelunate, , the number of the latter is one, less frequently two. Except this prelunate there are 2 or 3 collateral short accompanying sulci.
11. The dimensions of the cuneus on the medial surface are inclined to be a little broader by the lunate specimens. The angles between the calcarine and parieto- sulci oscilate between 70° and 89°. It seems that there is no correlative relation between this angle and lunate.
12. By the lunate specimens are the intraparietal sulci not straight and run nearer to the mantle rim. At their caudal end the medial branch of the is longer than the lateral.
13. When a circumscript elevation on the outer surface of the lobe may be called as operculum, there are 126 examples among 180 hemispheres. In the 101 lunate specimens there are 55 distinct, 24 not so much distinct operculum, 79 in total.
14. The sulci which limit the operculum at the upper margin are almost always the , at the lateral margin are the lunate, and when the latter deficient the lateral .
15. The lateral is distinct in 168 among 180 hemispheres, and when the lunate is present it lies always medial to the lateral and horizontal. The anastmosis with the lateral comes to the temporalis medius frequently (62 among 180).
16. The upper and lower sulci are less marked by the lunate brains.

抄録全体を表示

Homo erectus has been broadly defined to include fossils from Africa, Asia, and possibly Europe, or restricted to a supposedly confined Asian clade. Recently discovered fossils of H. erectus are allowing new insights into aspects of its evolution, such as the timing and mode of the species’ emergence in Africa and its relationship to Asian populations. However, the currently available African record predating 1.0 Ma is poor, consisting of the Turkana basin, Olduvai and the more limited South African materials. Here, we describe and compare eight craniodental fossils of ~1.4 Ma recovered from Konso, Ethiopia, that we attribute to H. erectus. These include KGA10-1, one of the better-preserved H. erectus mandibular specimens known from eastern Africa, and other fragmentary dental and cranial remains. The Konso H. erectus fossils show a mosaic of primitive and derived features. These include a large and thick mandibular corpus, a moderately developed lateral prominence, a reduced premolar morphology, and a tendency for smaller relative sizes of the posterior molars compared with earlier Homo. In some dentognathic details, such as the lack of a buccolingually narrow M1 and the presence of double mental foramina, the Konso fossils differ from eastern African H. erectus of ≥1.5 Ma. The fragmentary cranial remains exhibit weak angular and tori, and an apparently weak flexion, as with the eastern African H. erectus examples known from ~1.65 to 1.2 Ma. The available evidence is consistent with the interpretation that African early H. erectus shows morphological continuity within the ~1.65 to 1.0 Ma time period, with relatively little morphological evolution prior to 1.4 Ma and advanced dentognathic gracility occurring sometime thereafter. The Konso evidence corroborates the hypothesis that the African H. erectus populations represent a variable but continuous evolutionary succession that was a likely source of multiple events of gene flow to the Eurasian continent.

抄録全体を表示

Recently, many functional areas have been identified in the parietal cortex of the brain in monkeys, and owing to this, cytoarchitectonic subdivision has been elaborated in the monkey parietal cortex. This review deals with sulcal patterns of the parietal lobe in human and monkey brains, and corticocortical connections of both neurophysiologi-cally defined regions and cytoarchitectonic areas of the parietal cortex in monkeys. The author proposes that the is a boundary between the parietal and cortices in the human brain. A brain map of the monkey is presented. The parietal cortical areas are subdivided into somatosensory, eye movement related, hand or upper limb movement related, vestibular, and auditory areas, according to neu-rophysiologically defined functions of individual cortical areas. The somatosensory system contains areas 3a, 3b, 1, 2, 5, 7b, and SII: S1 projects to motor and premotor areas and somatosensory association areas project to premotor areas, the prefrontal, temporal, and limbic cortices, and the hippocampus. The eye movement system is composed of areas 7a, LIP, and PIP: It receives input from visual and temporal cortices and sends output to premotor areas, the prefrontal cortex, and the hippocampus. Hand movements are mediated in areas AIP, VIP, CIP, MIP, PEc, and V6A: These areas receive afferents from somatosensory areas, visual and temporal cortices and send efferents to the ventral premotor area. The vestibular functions are executed by coordination of areas 3aNV, 3aHV, 2NV, Ri, and VPS: These areas reciprocate with the cingulate cortex and insula and project to the ventral premotor area, SWA, and frontal eye field. The auditory system involves areas VIP and LIP: It receives afferents from the superior temporal sulcal cortex and sends efferents to the premotor area, frontal eye field, and prefrontal cortex.

抄録全体を表示

Cerebral venous thrombosis presenting as subarachnoid hemorrhage (SAH) is very rare. We present a woman with thrombosis of the superior sagittal, straight, and sigmoid sinuses who presented with SAH in the right temporal and bilateral cerebellar sulci. Brain perfusion CT demonstrated a delay of the mean transit time and high cerebral blood volume around the right posterior temporal lobe and cerebellum. These findings were compatible with venous congestion and they suggest the possibility that extension of the dural sinus thrombosis into the superficial veins caused localized venous hypertension with dilatation of the thin, fragile-walled cortical veins which eventually ruptured into the subarachnoid space.

抄録全体を表示

Ngawi 1 is an undated but well-preserved Homo erectus calvaria from Java. Previous craniometric and morphological studies have shown its similarities to late Javanese H. erectus from Ngandong as well as Sambungmacan (Sm 1 [and Sm 3]). Some researchers emphasize their morphological homogeneity, and suggest that this ‘Ngandong/Sambungmacan/Ngawi group’ is morphologically distinct from H. erectus from the Early Pleistocene of Sangiran and Trinil, possibly at a species-level. In this study, we reinvestigated Ngawi 1 based on the newly cleaned original specimen and using micro-computed tomography with the aim of testing if such morphological discontinuity really exists within the Javanese fossil record. We metrically and non-metrically examined 33 cranial characters that are useful to distinguish earlier and later Javanese H. erectus. We also evaluated the morphology of the three Sambungmacan crania (Sm 1, 3, and 4) in the same way. The results of these and multivariate analyses support previous studies that Ngawi 1 exhibits many characteristic features of Ngandong H. erectus. However, Ngawi 1 is more or less similar to earlier Javanese H. erectus in smaller cranial size, a weak but distinct supraglabellar depression, a relatively short temporal bone, limited posterior projection of the middle part of the torus, a shallower and ‘roofed’ mandibular fossa, and a smaller mastoid process. The three Sambungmacan crania also show general affinities to Ngandong, but are similar to earlier Javanese H. erectus in a few or more characters. Such slightly shifted character distribution is at least consistent with the hypothesis of continuous evolution of H. erectus through the Pleistocene of Java. This minor but potentially meaningful pattern of morphological variation should not be overlooked when a morphological group is defined for the specimens from Ngandong, Sambungmacan, and Ngawi. We also determined the endocranial volume of Ngawi 1 to be 959 cm³.

抄録全体を表示

A case of intracranial cholesterol granuloma is described in a 4-year-old neutered European male cat presented with a 5-month history of progressive weakness, ataxia and depression. On clinical evaluation, haematological and biochemical profiles revealed only mild hypercholesterolemia and magnetic resonance imaging showed a large space-occupying extra-axial mass in the area of the falx, not homogeneous after contrast enhancement. At post-mortem examination, an orange-yellowish mass of mm in diameter extended from the right frontal lobe to the temporo-parietal region, causing atrophy of the prosencephalic region of the brain. The site of origin of the mass was within the subarachnoid space of the supracallosum of the right cerebral hemisphere. Histological examination of the lesion revealed abundant deposits of cholesterol clefts, surrounded by clusters of macrophages and multinucleated giant cells. Neither inflammatory lesions, nor cholesterol deposits were detected in other areas of the brain and in other organs. On the basis of the histological examination, a diagnosis of intracranial cholesterol granuloma was made.

抄録全体を表示

The Lower Gondwana Kundaram Formation of the Pranhita-Godavari valley records the sole occurrence of Permian amniotes in India. The horizon has yielded various dicynodonts, mainly represented by medium-sized Endothiodon. This assemblage also contains several small dicynodonts belonging to the family Pristerodontidae and Emydopidae. Pristerodon (P. mackayi Huxley, 1868), Emydops (E. platyceps Broom and Haughton, 1917) and Cistecephalus (C. microrhinus Owen, 1876) are described here. This is the first detailed description of these genera from outside Africa. The older name Emydops in place of Emydoses is retained and the Indian specimens of Pristerodon, Emydops and Cistecephalus are compared with those from the Beaufort Group, Karoo Supergroup of South Africa. Based on its vertebrate fauna, the Kundaram Formation is broadly correlated with the Tropidostoma and Cistecephalus Assemblage Zones of the Beaufort Group, Karoo Supergroup, South Africa, the basal beds of the Madumabisa Mudstones of Zambia, the Ruhuhu and the lower part of the Kawinga Formation of Tanzania and the Morro Pelado Member of the Rio do Rasto Formation of Brazil. It suggests a Late Permian Tatarian age for the Kundaram Formation. The distribution of the Kundaram dicynodonts in the other Gondwanan countries indicates the close proximity of the continents during that period and a lack of endemism or provinciality.

抄録全体を表示

Objective: The mechanism of transient cortical blindness after endovascular treatment—a rare phenomenon—has not been elucidated; however, it is assumed to be related to contrast medium leakage (CML). We investigated the relationship between postoperative CML and cortical blindness in patients who underwent endovascular treatment for vascular lesions of posterior circulation.

Methods: This retrospective cohort study included 28 patients who underwent endovascular treatment for posterior circulation aneurysms at our hospital between January 2014 and December 2018. Cerebral CT was performed immediately after endovascular treatment and 24 h later. CT images were retrospectively evaluated with special interest in the presence and distribution of leakage of the contrast medium (CM). Patients were classified into the following three groups based on CT findings: Group A, no CML (11 patients); Group B, unilateral CML (5 patients); and Group C, bilateral CML (9 patients).

Results: The posterior circulation aneurysms were located in the basilar artery in 13 (52.0%) cases, in the posterior cerebral artery in 1 (4.0%) case, and in the vertebral artery in 11 (44.0%) cases. There was no difference regarding the adjunctive technique used for endovascular treatment between the groups. Patients in Group C used a significantly larger amount of CM than those in the other two groups. A longer operation time was associated with a larger amount of CM used during treatment. VerifyNow assay revealed that the P2Y12 reaction unit was significantly lower in Groups B and C. Cortical blindness was transiently observed in 2 of 9 patients (

.2%) in Group C, both of which showed CML surrounding the bilateral parieto- .

Conclusion: Both patients with cortical blindness showed bilateral CML, both of which showed CML surrounding the bilateral parieto-

. The CM-induced blood–brain barrier disruption may be the cause of cortical blindness.

抄録全体を表示

The males, mature larvae, and a nest of an Australian paper wasp, Ropalidia proletaria Richards, 1978, are described for the first time. Not only the female adult morphology but also the morphologies of the male, larva, and nest suggest that R. proletaria is closely related to R. plebeiana Richards, 1978, rather than to R. revolutionalis (de Saussure, 1853) as Richards (1978) suggested.

抄録全体を表示

The morphological features of the first human parietal fossil found at the Shuidonggou site of Ningxia, China are described and compared with other specimens. Our results show that most of the features of the Shuidonggou parietal resemble those of modern humans. On the other hand, this specimen was found in situ adjacent to the erosional surface of the late Pleistocene stratum and exhibits a certain degree of fossilization. There are two features which are different from modern humans and similar to those of fossil hominids. One of the features is the strong ridges between the striae parietalis suggesting that the temporalis muscles were more developed than in modern humans. The second feature is the lack of a sigmoid at the mastoid angle of the Shuidonggou parietal which is similar to the situation seen in Homo erectus of Zhoukoudian. Given the similarities of many morphological features between late Pleistocene and modern humans, it is impossible to set the age or evolutionary status of the fossil accurately just from skeletal morphology of a fragmentary parietal. Nevertheless, taking the specimen’s fossilization and the background information of the site into consideration, we believe that the parietal likely comes from the late Pleistocene human populations that lived in this area.

抄録全体を表示

A 74-year-old male presented with an intracranial hemorrhage caused by multiple dural arteriovenous fistulas (DAVFs) in the left

sinus and right sigmoid sinus. Four months previously, the patient underwent tongue cancer removal with lymph node dissection and ligation of the right internal jugular vein. Endovascular embolization (transvenous and transarterial embolization) resulted in the complete disappearance of the fistulas. Follow-up angiography revealed new arteriovenous shunts at the superior sagittal sinus and right sinus, and we treated the patient with staged transarterial embolization. Finally, venous congestion almost completely resolved and the DAVFs disappeared without any sign of recurrence. This case speculates the concept of DAVF as an acquired lesion caused by intravenous hypertension and alerts clinicians to take precautions against ligation of the internal jugular vein during a cervical operation.

抄録全体を表示

The tongue muscle develops from myogenic precursor cells that undergo long-range migration from the somites to tongue primordium. In this article, we aimed to overview cellular and molecular events taking place during the migration of tongue myogenic precursor cells in embryonic mice. Immunohistochemical techniques were used to determine the chronology and positions of desmin expression during early tongue development. Based on the three-dimensional (3D) reconstruction of serial desmin-immunostained images, we defined the discrete migration pathway of myogenic precursor cells as follows: somites→mesenchyme of trunk→ventral areas of the fourth→third and second branchial arches before arriving at the median mandibular arches around E10.3. The migrating myogenic precursor cells were characterized as desmin-positive/MyoD-negative cells with the development of lamellipodia and expression of Rho family genes. Once within the tongue primordium, myogenic precursor cells were ready to switch off their migratory phenotypes and express myogenic regulatory factors (MRFs). Although multiple signaling cues have been supposed to exert effects on the migration and terminal differentiation of tongue myogenic precursor cells, the exact molecular mechanisms and cellular interactions remain to be elucidated.

抄録全体を表示

In 6 equine specimens of both sexes, the morphological features of the cleavage lines of the skin over the entire body were examined using a metal probe with a sharp conical point. Wounds were produced on the skin with the probe and painted with Chinese white or Indian ink. The direction of running of the cleavage lines was determined from their relationship to the long axis of each region or area of the physical structure. The cleavage lines of the head and face revealed a fixed pattern in all specimens. They were similar to those of equine fetuses of 6 to 7 months of age. A pattern was found on the skin of the neck, trunk (abdomen), roots of the ear and tail, and external genital labium, except in some localized areas. The cleavage lines of the free extremities of the appendages already displayed a strikingly longitudinal pattern. A horizontal pattern was found in the middle costal region. It was clearer in the adult horse than in the equine fetus. The cleavage lines were annular in arrangement on the skin around the nares, eyes, and preputial orifice. They showed a convergent pattern on the skin of the metacarpal and metatarsal calcars, the umbilicus and anus. Some aspects of the skin tension were compared between the horse and certain other animals.

抄録全体を表示

KEEGENBERGの採集品やMONKEのタイプを研究してDamesellidaeの発生史, Damesella paronaiやAmphoton deoisの唇その他について新事実を見出した。MONKEの原品中にMyonaの含まれている事も興味ある新事実として附記しておく。

抄録全体を表示