IL-28B (IFN-λ3) and IFN-α synergistically inhibit HCV replication.

Genetic variation in the IL-28B (interleukin-28B; interferon lambda 3) region has been associated with sustained virological response (SVR) rates in patients with chronic hepatitis C treated with peginterferon-α and ribavirin. However, the mechanisms by which polymorphisms in the IL-28B gene region affect host antiviral responses are not well understood. Using the HCV 1b and 2a replicon system, we compared the effects of IFN-λs and IFN-α on HCV RNA replication. The anti-HCV effect of IFN-λ3 and IFN-α in combination was also assessed. Changes in gene expression induced by IFN-λ3 and IFN-α were compared using cDNA microarray analysis. IFN-λs at concentrations of 1 ng/mL or more exhibited concentration- and time-dependent HCV inhibition. In combination, IFN-λ3 and IFN-α had a synergistic anti-HCV effect; however, no synergistic enhancement was observed for interferon-stimulated response element (ISRE) activity or upregulation of interferon-stimulated genes (ISGs). With respect to the time course of ISG upregulation, the peak of IFN-λ3-induced gene expression occurred later and lasted longer than that induced by IFN-α. In addition, although the genes upregulated by IFN-α and IFN-λ3 were similar to microarray analysis, interferon-stimulated gene expression appeared early and was prolonged by combined administration of these two IFNs. In conclusion, IFN-α and IFN-λ3 in combination showed synergistic anti-HCV activity in vitro. Differences in time-dependent upregulation of these genes might contribute to the synergistic antiviral activity.

Primary neurons of the lateral line nerves and their central projections in hagfishes.

The hagfish lateral line system was studied by horseradish peroxidase transganglionic transport. The anterior lateral line nerve innervates the group of lateral line canals situated anteriorly to the eye, and the posterior lateral line nerve innervates the group of canals situated posteriorly to the eye. Although both nerves pass through the muscle fascia at the same point, each runs a different course to the brain. The anterior lateral line nerve runs near the trigeminal nerve and its ganglion is closely attached to the trigeminal ganglion, but both systems are completely independent. The posterior lateral line nerve runs independently of any other cranial nerve and makes a peculiar U-turn at the point of entry to the brain capsule. The anterior lateral line ganglion contains both cutaneous sensory cells (small to large cells) and lateral line sensory cells (small cells); from this ganglion projections run to both the trigeminal sensory nucleus (fine and thick fibers) and medial nucleus of the area acousticolateralis (fine fibers). The posterior lateral line ganglion contains only small lateral line cells that project fine fibers to the medial nucleus of the area acousticolateralis. There are no efferent components in this lateral line system, and its only afferent terminal field is the medial nucleus of the area acousticolateralis.

Nickel sulfate-specific suppressor T cells induced by nickel sulfate in drinking water.

Suppressor T cell function was studied in nickel sulfate (NiSO4) delayed type hypersensitivity (DTH). NiSO4 in drinking water administered orally to normal mice for 10 weeks elicited no significant footpad swelling. However, after drinking water for 7 weeks, suppression of footpad swelling response was not detected. Suppression of footpad swelling response was mediated by CD4-8+ T cells. However, these suppressor T cells did not overcome CD4+8- helper T cells by co-transfer to recipient mice. Unresponsiveness to NiSO4 by oral administration of antigen was due to suppressor T cells.

Somatosensory and visual correlation in the optic tectum of a python, Python regius: a horseradish peroxidase and Golgi study.

In snakes with infrared receptors the optic tectum receives infrared input in addition to visual and general somatosensory inputs. In order to observe their tectal termination patterns in ball pythons, Python regius, we injected horseradish peroxidase (HRP) into the nucleus of the lateral descending trigeminal tract (LTTD) which mediates infrared information, the optic nerve, and the nucleus of the trigeminal descending tract (TTD) which relays general somatosensory information. Fibers from LTTD were found in layers 5-13 of the contralateral optic tectum, and were especially dense in layers 7a-8. Optic nerve fibers terminated in layers 7a-13 of the contralateral tectum, and mainly in layers 12-13. TTD fibers were few, and could be seen in only the rostral half of the contralateral tectum. These fibers were found in layers 5-7b, but mainly in layers 6-7a. Among various types of neurons stained by the Golgi-Cox method, we focused on six types of neurons whose dendritic arborization overlapped with the distribution of the terminals of these sensory afferents described above. It is possible that these different sensory modalities converge on a single neuron of the various types.

Retinal projections in the hagfish, Eptatretus burgeri.

The retinal projections of hagfish were investigated by anterograde transport of HRP and the Nauta-Gygax method. The pathway coincided with the commissura postoptica of Jansen after complete crossing within the hypothalamus. Many projections were found in the contralateral 'area pretectalis', but there were only a few projections in the tectum mesencephali, the pars ventralis thalami, and the n. tuberculi posterioris of Jansen.

A new tectal afferent nucleus of the infrared sensory system in the medulla oblongata of Crotaline snakes.

The existence of an infrared sensory neuron group with ascending fibers which directly reach the optic tectum in Crotaline snakes was confirmed with three methods. (1) With the retrograde horseradish peroxidase (HRP) method, labeled neurons were not found within the nucleus descendens lateralis nervi trigemini (DLV), but in an unnamed cell group located immediately ventral to the DLV of the contralateral side at the transitional portion between the nucleus oralis (DVo) and the nucleus interpolaris (DVi). This unnamed cell group, which was seen only in the Crotalinae, was provisionally called the 'new nucleus'. (2) Normal brain series of 15 species were stained by the methods of Bodian-Otsuka, Klüver-Barrera and Nissl staining to compare the cytoarchitecture of the medulla oblongata. The 'new nucleus' was found only in species belonging to the Crotalinae. This nucleus was situated in fiber tracts which appeared to correspond to the lemniscus spinalis and tractus spino-cerebellaris of the reptilian medulla oblongata, and contained medium-sized multipolar or fusiform neurons. (3) In an electrophysiological study 16 single units responding unimodally to an infrared stimulus were recorded. Three of these recording sites were determined with Pontamine sky blue marking to be near or within the 'new nucleus'.

Primary vestibular projections in the hagfish, Eptatretus burgeri.

The VIIIth cranial nerve projections in the hagfish, which has only one circular canal in the ear, were studied by transganglionic HRP transport. This nerve has two branches, the nervus utricularis (N. utr.) and the nervus saccularis (N. sac.), each with its own ganglion, the ganglion utriculare (G. utr.) and the ganglion sacculare (G. sac.), respectively. Although the G. sac. has uniformly small cells, the G. utr. consists of two separate cell masses, a ventral mass of large cells and a dorsal mass of small cells. The small cells were labeled in both ganglia after horseradish peroxidase (HRP) injection into the endolymphatic space. The greater part of the terminal areas of these two branches overlapped in the ventral nucleus of the area acoustico-lateralis, but the terminals of the N. sac. extended slightly further in a caudal direction. No projections to the primordial cerebellum and no retrogradely labeled cells in the brain were found. The large cells in the ventral part of the G. utr. seem to be general cutaneous neurons, and the dorsal part of the area acousticolateralis seems to receive lateral line input.

Brain and liver pathology in a patient with carnitine deficiency.

The ultrastructural brain and liver pathology in an infant, who died of acute encephalopathy due to systemic carnitine deficiency (CD), an important condition mimicking Reye's syndrome (RS), was reported. The major finding in the brain was swelling of astrocyte cytoplasm. Expanded mitochondria in nerve cells and myelin sheath splitting in the white matter, which have been reported to be specific to RS, were not observed. Also in contrast to findings in RS, hepatocytes were filled with macrovesicular fat droplets without expanded mitochondria. These findings suggest significant differences in the pathophysiology of acute encephalopathy in CD and RS, although the clinical and laboratory findings during an episode of acute encephalopathy in the former are usually very similar to those in the latter.

Effects of prone and supine position on heart rate, respiratory rate and motor activity in fullterm newborn infants.

Polygraphic recordings were obtained for 24 normal full-term neonates on their 4th or 5th day of life. Thirteen of the infants were first fed, laid supine for 3 hours, fed again around noon and laid prone for 3 more hours. The other 11 were first laid prone and then supine. The awake state was observed more in the supine than the prone position (P less than 0.001). Wakefulness occurred at the expense of state 1 and/or state 2. The heart rate (HR) was higher in babies lying prone. It was also higher in the afternoon than in the morning. No such relationship was found for the respiratory rate (RR). There was higher average EMG activity during state 1 in the prone position. The cross-correlation between HR and EMG activity was positive during state 2, and states 4 and 5, regardless of the position. The cross-correlation between the RR and the EMG was usually negative in state 2, and in states 4 and 5, there being many exceptions. The cross-correlation between breathing and heart-beat was mostly negative during state 2, but it eventually became positive due to periodic breathing, central apnoeas with bradycardia, stretches, and crawling movements.

Diaphragm muscle pathology in Fukuyama type congenital muscular dystrophy.

The diaphragm muscle pathology in four patients with Fukuyama type congenital progressive muscular dystrophy (FCMD) was reported. In the diaphragm muscle fibers of three patients aged more than 14 years exhibiting chronic respiratory failure, a lot of electron dense lesions, which varied in size but did not extend over the whole length of the muscle fibers, and a marked increase in mitochondria were observed as well as the dystrophic changes. The dense lesions, consisting of electron dense fibrillary material comparable to Z-band materials in electron density, seemed to be due to Z-band disruption leading to streaming and/or large aggregations of Z-band materials. No mitochondria or other microorganelles were found in these dense lesions. These findings are thought not to be specific to FCMD, but seem to reflect diaphragm muscle fatigue, because, there were no such lesions in the diaphragm muscle of a 2-year-old infant not exhibiting chronic respiratory failure or in muscle at other sites in all patients.

Cystinuria with congenital myotonic dystrophy.

Two brothers with congenital myotonic dystrophy also had cystinuria with large renal stones. This report is the first to document the concurrence of cystinuria and congenital myotonic dystrophy. It is uncertain whether these two conditions are coincidental or share a common pathogenesis.

Myelin splitting in the spongy lesion in Leigh encephalopathy.

A spongy lesion consists of numerous vacuoles, mainly in the central gray matter, and is a characteristic finding in subacute necrotizing encephalopathy (Leigh encephalopathy); the cause of this lesion is unknown. An ultrastructural study on the vacuolated lesions in the left putamen of a patient with subacute necrotizing encephalopathy due to a deficiency of mitochondrial enzyme complexes I and IV revealed that the vacuoles were formed through the splitting of myelin. Because myelin splitting is commonly caused by toxic or metabolic diseases in humans and experimental animals, we believe that the vacuolation was due to the splitting of myelin which was caused by abnormal mitochondrial metabolism, even though this lesion is most commonly found in the white matter. We do not know whether the spongy lesion is formed only through myelin splitting in patients with subacute necrotizing encephalopathy; however, myelin splitting must play an important role in the formation of the spongy lesion.

[The brain of the Agnatha].

The brain of the Agnatha, especially of the hagfish, is discussed from the viewpoint of the telencephalon and the olfactory, visual, trigeminal, and vestibulolateral sensory systems. Myxiniformes and Petromyzontiformes, which were an independent group in the Ordovician, are thought to represent some parallels of ancestral vertebrate brains. It is interesting to study the brain of the Agnatha to investigate the process of the evolution of the vertebrate brain. In comparison with the lamprey, the hagfish has subcutaneous eyes under an unpigmented patch of skin, 4 paired tentacles at the rostral tip of the head, one semicircular canal on each side, a regressed ventricular system, a "primordium hippocampi" of unresolved homology in the telencephalon, no pineal body, fusion of the habenula of both sides, a tectum opticum with unclear laminations, no macroscopical cerebellum, and optic decussation within the hypothalamus. The arrangements of the trigeminal subnuclei of the descending tract are different from each other, unlike those of other gnathosomata. In the hagfish, the distribution of fibers carrying input of the vestibulum and lateral line system within the area vestibulo-lateralis differs from that of the lamprey, which resembles the teleosts and cartilaginous fish in this respect. These differences may be caused by an independent origin within the Agnatha. The basic organization of the brain of the Agnatha, such as the prosencephalon, mesencephalon, and rhombencephalon are common to the gnathostomata, although some variations in development are included in the sensory centers and higher centers of information processing. The sensory neurons within the brain are found in the medulla oblongata in the Agnatha, whereas in the gnathostomata the mesencephalic nucleus of the trigeminal nerve has been formed in connection with the development of the mandibula.

Afferent connections to the tectum mesencephali in the hagfish, Eptatretus burgeri: an HRP study.

The afferent connections to the tectum mesencephali were determined by unilateral injections of HRP in the hagfish, Eptatretus burgeri, whose eyes are degenerate and buried below the skin. Retrogradely labeled cells were observed ipsilaterally in the hypothalamus, lateral part of the pars ventralis thalami of Jansen, and nucl. reticularis mesencephali, and contralaterally in the tectum, nucl. sensorius n. V, area acoustico-lateralis, and "nucl. funiculi dorsalis". Of these non-visual afferents to the tectum, the trigeminal sensory nucleus contributed the greatest number, which ascended along the lemniscus bulbaris after crossing in the commissura ventralis. Retrogradely labeled fibers of the optic nerve could not be recognized in this study, although in a previous study the superficial layer of the tectum mesencephali received a few projections from the contralateral eye. These data are compared with the data from other animals and previous histochemical investigations.

Afferent and efferent connections of the central prosencephalic nucleus in the Pacific hagfish.

Injections of horseradish peroxidase, or the carbocyanine dye Dil, into the central prosencephalic nucleus of hagfishes reveal reciprocal connections with the septum, preoptic area, habenula, thalamus and hypothalamus. Efferent projections also occur to the olfactory bulb, pallium, posterior tubercle and tegmentum and to the contralateral central prosencephalic nucleus. These connections suggest that the central prosencephalic nucleus of hagfishes may be homologous to portions of the medial pallium and ventral thalamus of other craniates.

Histopathological study of focal dermal hypoplasia (Goltz syndrome).

We report a case of focal dermal hypoplasia, or Golz syndrome in a 13-year-old girl. The patient presented with a variety of cutaneous defects, including atrophy-like depressions, striations, a verrucous papilloma, and lipomas. Histopathological examination showed deposits of fat cells or adipose tissue in the dermis, which were subepidermal, mid-dermal, perivascular, or involved the whole dermis. These findings indicate that the adipose tissue in the dermis is a result of dermal dysplasia and not hypoplasia.

Ultrastructure of the crotaline snake infrared pit receptors: SEM confirmation of TEM findings.

BACKGROUND: Crotaline snakes possess a pair of infrared-sensing pit organs that aid the eyes in the detection and apprehension of prey. The morphology of the receptors in the pit organs has been studied by light and transmission electron microscopy, and the ultrastructure of the receptors has been inferred from the results of this work. But this theoretical reconstruction has never been confirmed by any kind of three-dimensional imaging. METHODS: We treated the receptor-containing membrane of the pit organs with potassium hydroxide to remove collagen and expose the receptors, which we then viewed by scanning electron microscopy. RESULTS: We were able to obtain three-dimensional views of all structures previously reported to exist within the receptor-containing membrane: terminal nerve masses formed from free nerve endings, supporting Schwann cells within the nerve masses, unmyelinated and myelinated nerve fibers, a capillary bed, and vacuole cells. CONCLUSIONS: By providing the first three-dimensional views of the infrared receptors, we have confirmed that previous theoretical reconstructions of the receptors were substantially correct and have provided new evidence of the spatial arrangement of the receptors in a monolayer array.

Microvasculature of crotaline snake pit organs: possible function as a heat exchange mechanism.

The infrared sensory membranes of the pit organs of pit vipers have an extremely rich capillary vasculature, which has been noted passim in the literature, but never illustrated or studied in detail. We rendered the pit vasculature visible in various ways, namely, by microinjection of India ink, by a combination of ink and succinate dehydrogenase staining, and by making resin casts for scanning electron microscope study. We also used transmission electron microscopy for identifying the types (arterioles, venules, capillaries) of blood vessels. Then we compared the pit vasculature with that of the retina and the dermis. Good visualization of the vasculature was obtained with both ink and resin injection. Arterioles, venules, and capillaries could be distinguished with all methods used. The monolayer vasculature was denser in the pit membrane than in the retina or skin. Each loop of the network enclosed a small number of infrared receptors so that all receptors were in contact with a capillary on at least one side. The forward-looking areas of the pit had a denser network than side-looking areas. Since infrared rays cause nerve impulses by raising the temperature of individual receptors, the capillary network functions not only as a supplier of energy but also as a cooling mechanism to reduce afterimages. Thus the denser network in the forward-looking areas causes these areas to be more sensitive and have better image resolution than the rest of the membrane.