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T Kosaka

Publications and source records attributed to T Kosaka.

At least 91 records · Page 5Linked to original sources

How simple is the organization of the olfactory glomerulus?: the heterogeneity of so-called periglomerular cells.

Recent progress in the studies of the olfactory system, especially in the molecular biological studies, makes it one of the useful sensory model systems for understanding neural mechanisms for the information processing. In the olfactory bulb, the primary center of the olfactory system, glomeruli are regarded as important functional units in the transmission of odorant signals and in processing the olfactory information, but have been believed to be composed by only a small number of neuronal types and thus to be simple in their neuronal and synaptic organization. However, accumulating morphological data reveal that each type of neurons might further consist of several different subpopulations, indicating that the organization of glomeruli might not be so simple as it was believed. Here we describe an aspect of the structural organization of glomeruli, focusing on the heterogeneities of periglomerular neurons in mammalian main olfactory bulb.

Animals↗

Distribution of calretinin immunoreactivity in the mouse dentate gyrus: II. Mossy cells, with special reference to their dorsoventral difference in calretinin immunoreactivity.

In our previous study we revealed the presence of clustered large calretinin-immunoreactive multipolar cells in the ventral hilus of the mouse dentate gyrus and indicated that they might be mossy cells, the principal neurons in the dentate hilus. In the present study we confirmed this identification with several methods and analysed further in detail. In Golgi-impregnated samples mossy cells were easily identified by their locations and characteristic thorny excrescences on their proximal dendrites. Golgi-impregnated mossy cells were observed not only in the ventral hilus but also in the dorsal hilus, where no calretinin-immunoreactive large multipolar cells were encountered. Interestingly, mossy cells exhibited dorsoventral differences in the size and complexity of thorny excrescences; mossy cells at the dorsal and middle levels had larger and more complex thorny excrescences, which covered dendritic shafts for a longer distance, while ventral mossy cells had smaller, simpler and shorter thorny excrescences. Confocal laser scanning light microscopic observations at a high magnification showed that the vast majority of calretinin-immunoreactive large neurons in the ventral hilus displayed the thorny excrescences characteristic to mossy cells. Mossy cells identified with the intracellular injection of Lucifer Yellow were calretinin-immunoreactive. Electron microscopic observations clearly revealed that calretinin-immunoreactive elements showed structural features of mossy cells such as thorny excrescences receiving typical synapses from mossy fibre terminals. At the supragranular zone, a well-known target zone of mossy cell axons, a dense calretinin-immunoreactive band was seen, where numerous calretinin-immunoreactive punctae and fibres were packed. Electron microscopic observations revealed that these calretinin-immunoreactive axon terminals in the supragranular zone made asymmetrical synapses on presumed granule cell dendritic spines. Tracer injection studies and lesion experiments indicated that the supragranular calretinin-immunoreactive axon terminals mainly originated from the large calretinin-immunoreactive multipolar cells in the ipsilateral ventral hilus. Fluorescent double immunostaining for calretinin and glutamate receptor 2/3 (GluR2/3) revealed that all large calretinin-immunoreactive hilar cells in the ventral level were GluR2/3-immunoreactive and almost all intensely GluR2/3-immunoreactive hilar cells in the ventral level were calretinin-immunoreactive. In addition intensely GluR2/3-immunoreactive but calretinin-negative large cells were encountered in the dentate hilus at the dorsal level. On the basis of these observations, we concluded that large calretinin-immunoreactive cells in the ventral hilus of the mouse dentate gyrus were really mossy cells and that mossy cells at the dorsal level were calretinin negative. The present study revealed that mouse mossy cells show the dorsoventral difference in the calretinin immunoreactivity and thus they are chemically heterogeneous.

Animals↗

Biologically active oligodeoxyribonucleotides. Part 11: The least phosphate-modification of quadruplex-forming hexadeoxyribonucleotide TGGGAG, bearing 3-and 5-end-modification, with anti-HIV-1 activity.

We have found that a hexadeoxyribonucleotide (5'TGGGAG3', R-95288), Koizumi, M. et al. Bioorganic & Medicinal Chemistry, 1997, 5, 2235, bearing a 3,4-dibenzyloxybenzyl (3,4-DBB) group at the 5'-end and a 2-hydroxyethylphosphate at the 3'-end, has high anti-HIV-1 activity and the least cytotoxicity in vitro and in vivo. In order to synthesize more potent hexadeoxyribonucleotides, we substituted phosphodiester (P-O) bonds in the 6-mer with the least phosphorothioate (P-S), phosphoramidate (P-N), or methylphosphonate (P-Me) bonds. When more than two P-N or P-Me bonds were introduced into a 6-mer, the phosphate-modified 6-mers had weak or no anti-HIV- activity, in spite of quadruplex structure formation. However, when P-S bonds were substituted for P-O bonds, anti-HIV-1 activity of their 6-mers did not dramatically decrease, compared with compounds substituted with P-N or P-Me bonds. The results suggest that the formation of a quadruplex structure is not always sufficient for anti-HIV-1 activity of the 6-mer, and that net negative charges derived from P-O or P-S bonds in the quadruplex are important for anti-HIV-1 activity. Moreover, among various phosphate-modified ODNs, we found that the anti-HIV-1 activity of ODN PS7 with only one P-S bond was the same as that of R-95288, both having a high stability in human plasma.

Anti-HIV Agents↗

Long-term therapy with an ACE inhibitor, temocapril, reduces microalbuminuria in essential hypertension.

The present study was conducted to prospectively evaluate whether a new ACE inhibitor, temocapril, could modify urinary microalbumin excretion rate (UAE) in a group of hypertensive outpatients who had no evidence of renal impairment. Sixty-three outpatients (32 men and 31 women; mean age, 59.9 +/- 1.5 yr) with essential hypertension entered the study, all having been treated for at least 6 mo with dihydropyridine calcium-channel blockers (CCBs: nitrendipine, nisoldipine, or amlodipine). Their blood pressures (BPs) had been controlled to adequate levels with the CCBs. None had overt proteinuria (determined by Albustix) or abnormal serum creatinine levels. After 3 mo of baseline observation under the previous treatment, the subjects were randomly divided into two groups. In group A (n = 31), the previously used CCBs were switched to temocapril, 2 to 4 mg once daily for 12 mo, and BP was controlled at a level equivalent to that during CCB treatment. In group B (n = 32), the subjects were maintained on their previous treatment for a further 12 mo. The effect of temocapril on BP appeared to be clinically similar to that of the previously used CCBs, but it significantly decreased UAE as compared with the previous therapy. In group A, UAE decreased significantly (p < 0.01) from the baseline value of 38.9 +/- 5.1 mg/g creatinine (Cr) to 22.2 +/- 4.2 and 25.3 +/- 5.6 mg/g Cr at the 6th and 12th months of temocapril therapy, respectively. In contrast, in group B UAE was unchanged (baseline 39.8 +/- 6.6 mg/g Cr; 6 mo, 44.6 +/- 6.8; 12 mo, 45.9 +/- 7.7). In group A, 17 of 31 patients (54.8%) had abnormal UAE levels (> or = 29.5 mg/g Cr) during previous therapy with CCBs, but 6 mo after switching to temocapril 25 of these patients (80.6%) had normal UAE (< 29.5 mg/g Cr). In group B, 15 of 32 patients (46.9%) had abnormal UAE levels during the observation period, and these abnormal UAE levels remained unchanged; 17 of the 32 patients (53.1%) had abnormal UAE levels after a further 6 mo of continued CCBs therapy. We conclude that long-term therapy with temocapril may provide renal protection by reducing UAE even in hypertensive patients with no evidence of renal impairment.

Albuminuria↗

Intraperitoneal insemination of the guinea pig with synchronized estrus induced by progesterone implant.

Female guinea pigs with synchronized ovulation by means of implantation of progesterone-filled tubing (P-tube) followed by a progesterone injection, were inseminated by intraperitoneal injection with sperm suspension. First, to obtain the optimum conditions for insemination, the females were inseminated singly over the range of 1-10 x 10(7) spermatozoa before and after the synchronized ovulation. The incidence of conception and implantation was 100% in the females given more than 5 x 10(7)/animal at 9:00 h on the 5th day after removal of the P-tube. Second, the reproductive ability of the inseminated females under this optimal condition was observed throughout the pregnancy to delivery. Inseminated females had a mean +/- S.D. gestation period of 68.7 +/- 0.5 days, a litter size of 2.8 +/- 0.6 pups and body weight of 110 +/- 14 g. These data were comparable to those of naturally-mated females. Our findings suggest that the artificial insemination by intraperitoneal injection in combination with the synchronized estrus technique is very useful for production control in a small colony of guinea pigs.

Animal Husbandry↗

[Effect of low-dose CDDP/5-FU therapy on thymidylate synthase content].

Low-dose therapy consisting of cisplatin plus 5-fluorouracil was given to 20 patients with advanced gastric cancer, and specimens were obtained to evaluate levels of 5-fluorodeoxyuridine (FdUMP) and thymidylate synthase (TS), indices of DNA, and proliferating nuclear cell antigen (PCNA). There was a significant correlation between the levels of FdUMP, total TS and free TS in cancer and in normal gastric mucosa, respectively. Total TS of cancer was higher than that of normal tissue, at 5.3 +/- 4.8 and 3.4 +/- 2.2 pmol/g, respectively. On the other hand, there was no relationship nor difference between The TSIR ratio of cancer and normal mucosa. The FdUMP levels of far advanced cancer showed a tendency to be lower than those of the less advanced one, especially in liver metastasis. The total TS was higher in intestinal type and in INF alpha or beta. The free TS was higher in invasive type, liver metastasis and curability C. The TSIR ratio showed a tendency to be lower in far advanced cases, such as invasive type and INF gamma. The correlation between DNA index and TS values and between PCNA labeling index and TS values were good. These results suggest that TS levels would be a predictor for malignant potential as well as for chemosensitivity.

Adult↗

[Evaluation of intra-arterial infusion chemotherapy for advanced gastric cancer].

We evaluated the therapeutic efficacy of intraarterial infusion chemotherapy in advanced gastric cancer, its side effect and patient prognosis, in comparison with systemic infusion. Of 125 cases of advanced gastric cancer, 41 cases received intraarterial chemotherapy (A group) and the rest were given systemic infusion (S group). Protocols of chemotherapy were 5-FU + MTX in 49 cases, 5-FU + cisplatin in 62, and 5-FU + MMC in 14. Location of the disease was the peritoneum in 69 cases, nodes in 59, liver in 38, and other sites, 33. The response rate of A group was significantly higher than that of S group, at 31% and 13% respectively. Although 41% of cases showed side effects (> or = grade 2), there was no significant difference between the 2 groups. The median survival period and 1-year survival rate were 8.4 months and 35%, respectively, and there was no significant difference between the 2 groups. In cases with liver metastasis, the prognosis of A group was better than that of S group. The results suggest that intra-arterial infusion chemotherapy is an effective treatment for liver metastasis from gastric cancer.

Antineoplastic Combined Chemotherapy Protocols↗

[A randomized controlled trial with methotrexate (MTX), 5-fluorouracil (5-FU) and pirarubicin (THP) vs 5-FU alone in advanced or recurrent gastric carcinoma. Tokai Hokuriku THP Study Group].

A randomized controlled trial was designed to investigate the therapeutic benefit of a combination chemotherapy consisting of MTX, 5-FU and THP in patients with advanced or recurrent gastric carcinoma. The patients were randomized into two groups; Group A patients (n = 37) underwent our combined chemotherapy, whereas Group B (n = 34) underwent chemotherapy with 5-FU alone as a control. There were no significant differences in various background factors between the groups. The median survival time was roughly 170 days after the randomization for the patients with advanced cancer (n = 26 for Group A and n = 25 for Group B), with no significant difference between the groups. Two long survivors, however, belonged to Group A. The median survival time of 161 days for Group A (n = 11) was longer than that of Group B (84 days, n = 9), but the difference was not statistically significant. The incidence of toxicities (leukopenia in particular) exceeding JCOG grade 3 was significantly higher for Group A, but no morbidity was observed. These results imply that patients with advanced or recurrent gastric carcinoma may benefit from a regimen of MTX, 5-FU and THP.

Aged↗

Protective effects of the antiparkinsonian drugs talipexole and pramipexole against 1-methyl-4-phenylpyridinium-induced apoptotic death in human neuroblastoma SH-SY5Y cells.

Treatment of human neuroblastoma SH-SY5Y cells with 1 mM 1-methyl-4-phenylpyridinium (MPP+) for 3 days induced production of reactive oxygen species (ROS), followed by caspase-3 activation, cleavage of poly(ADP-ribose) polymerase (PARP), and apoptotic cell death with DNA fragmentation and characteristic morphological changes (condensed chromatin and fragmented nuclei). Simultaneous treatment with 1 mM talipexole slightly inhibited the MPP+-induced ROS production and apoptotic cell death. In contrast, pretreatment with 1 mM talipexole for 4 days markedly protected the cells against MPP+-induced apoptosis. However, this protective effect might not be mediated by dopamine receptors. The talipexole pretreatment induced an increase in antiapoptotic Bcl-2 protein level but had no effect on levels of proapoptotic Bax, Bak, and Bad. It also inhibited MPP+-induced ROS production, p53 expression, and cleavages of caspase-3 and PARP. Similarly, pramipexole pretreatment increased Bcl-2 and inhibited MPP+-induced apoptosis. Although pretreatment with bromocriptine also had a protective effect against MPP+-induced apoptosis, it had no effect on the protein levels of Bcl-2 family members. On the other hand, N6,2'-O-dibutyryl cAMP or calphostin C induced a decreased Bcl-2 level and enhanced MPP+-induced cell death. These results suggest that talipexole has dual actions: (1) it directly scavenges ROS, affording slight protection against MPP+-induced apoptosis, and (2) it induces Bcl-2 expression, thereby affording more potent protection, if it is administrated before MPP+. Pramipexole has similar effects, whereas bromocriptine seems to exhibit the former but not the latter effect.

1-Methyl-4-phenylpyridinium↗

Selective association of S100A6 (calcyclin)-immunoreactive astrocytes with the tangential migration pathway of subventricular zone cells in the rat.

In adult rodents, proliferating cells in the subventricular zone of lateral ventricle tangentially migrate into the olfactory bulb, where they become the interneurons. The present immunocytochemical analysis revealed that S100A6 (calcyclin), a specific calcium-binding protein of the S100 family, is restrictedly distributed in some astrocytes in the tangential migration pathway of the rat. These results suggest that a particular type of astrocytes containing S100A6 is associated with the tangential migration pathway.

Animals↗

Laminar distribution of non-principal neurons in the rat hippocampus, with special reference to their compositional difference among layers.

In the present study we examined the laminar distributions of four types of chemically defined subpopulations of non-principal neurons, that is, those immunoreactive for parvalbumin (PV), calretinin (CR), nitric oxide synthase (NOS) and somatostatin (SS), in the rat hippocampus, by estimating their approximate numerical densities (NDs) and percentages in specific layers according to the 'disector' principle. CR-immunoreactive (CR-IR) neurons and NOS-IR neurons were scattered throughout layers, but among layers in each subdivision their NDs were largest in the principal cell layers, where 30-45% of CR-IR and NOS-IR somata in each subdivision were located. In addition, CR-IR and NOS-IR somata were also concentrated at the border between the stratum radiatum (SR) and stratum lacunosum moleculare (SLM) in the CA1 region, where the NDs of these neurons were far larger than those in the SR/SLM as a whole and close to those in the stratum pyramidale (SP) (CR-IR somata at the ventral level and NOS-IR somata at the dorsal level) or larger (NOS-IR neurons at the ventral level). The NDs of CR-IR somata were dorsoventrally different in all layers of the CA3 region, the SR/SLM in the CA1 region and the hilus and the granule cell layer (GCL) of the dentate gyrus (DG), whereas the NDs of NOS-IR somata were dorsoventrally different in all layers of the CA3 region and the SP in the CA1 region. In contrast, approx. 90% of somatostatin-like immunoreactive (SS-LIR) neurons were located in the stratum oriens/alveus (SO/SA) in the CA1 region and in the hilus of the DG, where they were the most predominant cell type among the four types of non-principal cells. In contrast, in the CA3 region, SS-LIR somata were scattered in various layers. The majority (50-70%) of PV-IR neurons were located in the principal cell layers, whereas one-fourth to one-third of them were located in the SO/SA and hilus. The NDs in the SP of the CA1 and CA3 regions showed a significant dorsoventral difference. Although PV-IR somata were most numerous among the four non-principal cell groups in the SP of the dorsal CA1 region, they were not necessarily predominant in the principal layers in other regions, that is, in the ventral CA1 region, CA3 region and DG, where the NDs of CR-IR and/or NOS-IR somata were nearly equal to or larger than that of PV-IR somata. The present study not only reveals the laminar distribution patterns of four types of non-principal neurons in each subdivision quantitatively, but also illustrates the prominent differences in the compositions of four types of non-principal cells in each layer of each subdivision.

Animals↗

Quantitative analysis of GAD65 and GAD67 immunoreactivities in somata of GABAergic neurons in the mouse hippocampus proper (CA1 and CA3 regions), with special reference to parvalbumin-containing neurons.

Intensities of the immunoreactivities against two GAD isoforms, GAD65 and GAD67, were examined quantitatively in somata of GABAergic neurons in the mouse hippocampus proper. All labeled somata contained both isoforms but showed diverse immunoreactivities against them. The somata showing weak immunoreactivity for GAD65 but moderate to intense immunoreactivity for GAD67 were frequently located in the stratum pyramidale of the CA1 and CA3 regions and were mainly composed of parvalbumin-containing neurons, a particular subpopulation of hippocampal GABAergic neurons. These data revealed additional distinctive properties of parvalbumin-containing neurons and suggest their specialized roles in the hippocampal GABAergic system.

Animals↗

Distribution of nonprincipal neurons in the rat hippocampus, with special reference to their dorsoventral difference.

In the present study we examined the distribution of chemically identified subpopulations of nonprincipal neurons in the rat hippocampus, focusing on the dorsoventral differences in their distributions. The subpopulations analyzed were those immunoreactive for parvalbumin, calretinin, nitric oxide synthase, somatostatin, calbindin D28K, vasoactive intestinal polypeptide and cholecystokinin. Using a confocal laser scanning light microscope, we could confirm that the penetration of each immunostaining, except that of calbindin D28K, was complete throughout 50 microns thick sections under our immunostaining conditions. We counted numbers of immunoreactive somata according to the 'dissector' principle, measured areas of hippocampal subdivisions and the thickness of sections, and estimated the approximate numerical densities of these subpopulations, especially for those neurons immunoreactive for nitric oxide synthase, calretinin, somatostatin and parvalbumin. Generally speaking, neurons immunoreactive for parvalbumin showed no significant dorsoventral differences in the numerical densities in any of the subdivisions of the hippocampus, whereas the numerical densities of somata immunoreactive for calretinin, nitric oxide synthase and somatostatin were significantly larger in ventral levels than at dorsal levels of the hippocampus. The numerical density of somatostatin neurons was significantly larger in ventral levels than in dorsal levels of the denate gyrus, and, although not prominent, of the CA1 region. That of nitric oxide synthase positive neurons was significantly larger in ventral levels than in dorsal levels of the CA3 region as well as of the DG but not of the CA1 region. The numerical density of calretinin positive neurons was larger in ventral levels than in dorsal levels of all hippocampal subdivisions. The present study also revealed that dorsal and ventral levels of the hippocampus differ from each other in the composition of their nonprincipal neurons.

Animals↗

Exacerbated autoimmune hepatitis successfully treated with leukocytapheresis and bilirubin adsorption therapy.

A 58-year-old man with subacute fulminant onset of autoimmune hepatitis (AIH) was treated by leukocytapheresis (LCAP) and bilirubin adsorption therapy (BAT), rather than by administration of high-dose corticosteroids as he had mild glucose intolerance, and a definitive diagnosis of AIH was not obtained on admission; further, there was a risk of viral infection. After initiation of the therapies, serum transaminases and bilirubin, immunoglobulins, anti-nuclear antibodies, and rheumatoid factor decreased rapidly, as did the initially high levels of activated cells and several pro-inflammatory cytokines. Liver inflammation observed on liver biopsy settled during the course of the therapies, with no adverse side effects. A pause in the therapies was associated with deterioration; however, restoration of apheresis was followed by normalization. Remission was sustained throughout the period monitored, except for a recurrence 14 months after discharge, which was successfully resolved by two additional LCAP sessions. These results suggest that LCAP influences the causal mechanism(s) of exacerbation of AIH.

Adsorption↗

Relationship between radical production and natural killer cytotoxic factor (NKCF) in canine natural killer (NK) cell-mediated cytotoxicity.

The relationship between radical production and natural killer cytotoxic factor (NKCF) release via canine natural killer (NK)-mediated cytotoxic mechanism was examined. Radical production and NKCF release was induced in NK cells stimulated with either dead target cells, or their cytoplasmic membranes, as well as live target cells. Canine NKCF evoked target cell lysis but did not induce radical production. Radical production was inhibited by the addition of Tiron or n-propyl gallate, whereas NK-mediated cytotoxicity and NKCF release were only inhibited by the addition of n-propyl gallate. These results suggested that radical production and NKCF release may be induced by the contact and binding of NK cells to the target cell cytoplasmic membrane. Therefore, the release of NKCF from NK cells attached to the target cell cytoplasmic membrane may be associated with the production of radicals, especially hydroxyl radicals.

Animals↗

Differentiation of chemically defined neuronal populations in the transplanted olfactory bulb without olfactory receptor innervation.

Olfactory bulbs (OBs) from embryonic day 15 and 17 and postnatal day 1 mice were transplanted into the lateral ventricle of juvenile host mice without bulbectomy, and fine structural and chemical features of neurons and glia in the OB transplants were investigated immunocytochemically and electron microscopically. In the OB transplants there were neither clearly defined glomeruli nor layers, nor olfactory marker protein immunoreactive elements. However, chemically defined neuronal populations resembling those in the normal OBs such as those immunoreactive for gamma-aminobutyric acid (GABA), tyrosine hydroxylase and Ca(2+)-binding proteins (calbindin-D28K, calretinin, parvalbumin) were observed. Electron microscopically, dendrodendritic and somatodendritic reciprocal synapses, that is, synapses characteristic of the OB, were occasionally observed in the OB transplants. These results indicated that at least some embryonic or newborn mouse OB neurons and/or precursor cells could exhibit chemical properties and form typical synaptic contacts observed in normal OB, even when they received no inputs from olfactory receptor cells.

Animals↗

Chemically defined neuron groups and their subpopulations in the glomerular layer of the rat main olfactory bulb--II. Prominent differences in the intraglomerular dendritic arborization and their relationship to olfactory nerve terminals.

In the glomerular layer of the rat main olfactory bulb, we previously reported three chemically defined interneuron groups: GABA-like immunoreactive, calretinin-immunoreactive and Calbindin-D28k-immunoreactive groups [Kosaka K. et al. (1995) Neurosci. Res. 23, 73-88]. In the present study, we analysed the structural features of these three neuron groups using confocal laser scanning light microscopy, focusing on their dendritic arborization pattern, especially on their close apposition to olfactory receptor terminals labeled by olfactory marker protein. Each glomerulus consisted of two zones, the olfactory nerve zone and the non-olfactory nerve zone. The former was mainly occupied by olfactory nerve preterminals and terminals as well as their targets, postsynaptic fine dendritic portions of intrinsic neurons. The latter non-olfactory nerve zone was occupied mainly by olfactory marker protein-negative profiles. Processes of GABAergic neurons and those of one of their subpopulations, tyrosine hydroxylase-immunoreactive neurons, were numerous both in the olfactory nerve and non-olfactory nerve zones, resulting in their frequent close apposition to olfactory marker protein-immunoreactive elements. Combined confocal laser scanning light microscopic electron microscopic examination revealed synaptic contacts from olfactory nerve terminals on tyrosine hydroxylase-immunoreactive processes at these sites of close apposition. In contrast, calretinin-immunoreactive and Calbindin-D28k-immunoreactive processes, particularly Calbindin-D28k-immunoreactive ones, were distributed almost exclusively in the non-olfactory nerve zone, as if they avoided the olfactory nerve zone, showing a net or honeycomb pattern. Thus, calretinin-immunoreactive and Calbindin-D28k-immunoreactive processes were not or very rarely closely apposed to olfactory nerve terminals. These findings suggested that there might be some differences among chemically defined interneuronal groups in their synaptic contacts from olfactory nerves. Further quantitative image analysis clearly exhibited the prominent differences among these neuron groups in their intraglomerular dendritic arborization in relation with the olfactory nerve zone, i.e. the percentages of the area in the olfactory nerve zone occupied by GABAergic and tyrosine hydroxylase-immunoreactive processes were about 10%, respectively, whereas those of calretinin-immunoreactive and Calbindin-D28k-immunoreactive processes were only about 1% and 0.3%, respectively. These findings suggested that so-called periglomerular cells in glomeruli might be heterogeneous not only in their chemical nature, but also in their dendritic arborization pattern and synaptic contacts from olfactory nerve terminals.

Animals↗

Biologically active oligodeoxyribonucleotides--IX. Synthesis and anti-HIV-1 activity of hexadeoxyribonucleotides, TGGGAG, bearing 3'- and 5'-end-modification.

We have determined that hexadeoxyribonucleotides (5'TGGGAG3'), with modified aromatic groups such as a trityl group at the 5'-end, have anti-HIV-1 activity in vitro. The 6-mer bearing a 3,4-dibenzyloxybenzyl (3,4-DBB) group at the 5'-end had the most potent activity and the least cytotoxicity. When the 3'-end of the 5'-(3,4-DBB)-modified 6-mer was substituted with a 2-hydroxyethylphosphate, a 2-hydroxyethylthiophosphate, or a methylphosphate group at the 3'-end, anti-HIV-1 activity increased. Moreover, among various 3'- and 5'-end-modified 6-mers that were tested, the 6-mer (R-95288) bearing a 3,4-DBB group at the 5'-end and a 2-hydroxyethylphosphate group at the 3'-end was the most stable, when incubated with mouse, rat, or human plasma. Therefore, R-95288 was chosen as the best candidate for possible use in therapy on the basis of its anti-HIV-1 activity.

Animals↗