Effect of IL-12 on T-cell immune responses in patients with chronic HCV infection

As the host's immune responses may determine the outcome of hepatitis C virus (HCV) infection, and interleukin (IL)-12 plays an essential role in host defense against infectious diseases, we studied the antigen-specific and non-specific cellular immune responses in patients with chronic HCV infection. A proliferative response to phytohemagglutinin (PHA) was found in all 20 patients. Of the 20, 8 (40%) displayed a lymphocyte proliferation in response to HCV antigen c22, 2 (10%) to c33, 6 (30%) to c100-3, and 1 (5%) to NS5. The addition of rhIL-12 to cultures of peripheral blood mononuclear cells (PBMC) stimulated with PHA significantly enhanced the proliferative responses in normal controls as well as in HCV-infected subjects. The increased proliferation was also observed in HCV-infected patients when PBMC were co-cultured with HCV antigens c22 and c100-3 in the presence of rhIL-12. The production of interferon gamma (IFNgamma), IL-2, IL-4 and IL-10 was observed in 7 (58.3%), 5 (41.7%), 3 (25.0%) and 5 (41.7%) HCV-infected individuals stimulated with c22, and in 4 (33.3%), 2 (16.7%), 2 (16.7%) and 2 (16.7%) with c100-3, respectively. All HCV-infected individuals had increased production of cytokines IFNgamma, IL-2, IL-4 and IL-10 in supernatants of PBMC after stimulation with PHA. IL-12 significantly augmented Th1 cytokine production in HCV-infected individuals stimulated with PHA and with HCV antigens. In conclusion, deficient cellular immune responses are present in HCV-infected patients and IL-12 can enhance the immune responses in these patients.

Localization of M(2) muscarinic acetylcholine receptor protein in cholinergic and non-cholinergic terminals in rat hippocampus

The muscarinic receptor family (M(1)-M(4)) mediates cholinergic modulation of hippocampal transmission. Pharmacological and physiological studies have indicated that a presynaptic receptor on cholinergic terminals plays a key role in regulating ACh release, although the molecular identity of this subtype is uncertain. In this study, the localization of the M(2) receptor is described in detail for the pyramidal cell layer in the CAl region of the hippocampus. Electron microscopic analysis of M(2) immunoreactivity in this area revealed mainly presynaptic expression of this subtype. Double-labeling experiments using antibodies to M(2) and to the vesicular acetylcholine transporter, a novel, specific marker of cholinergic terminals, were used to investigate the nature of these presynaptic receptors. These studies have revealed that M(2) is located in cholinergic and non-cholinergic terminals. This is the first direct anatomical evidence that suggests that M(2) may indeed function as a cholinergic autoreceptor in the hippocampus. The distribution of the M(2) receptor in non-cholinergic terminals also suggests functional roles for M(2) as a presynaptic heteroreceptor.

Morphogenetic proteins SpoVID and SafA form a complex during assembly of the Bacillus subtilis spore coat

During endospore formation in Bacillus subtilis, over two dozen polypeptides are assembled into a multilayered structure known as the spore coat, which protects the cortex peptidoglycan (PG) and permits efficient germination. In the initial stages of coat assembly a protein known as CotE forms a ring around the forespore. A second morphogenetic protein, SpoVID, is required for maintenance of the CotE ring during the later stages, when most of proteins are assembled into the coat. Here, we report on a protein that appears to associate with SpoVID during the early stage of coat assembly. This protein, which we call SafA for SpoVID-associated factor A, is encoded by a locus previously known as yrbA. We confirmed the results of a previous study that showed safA mutant spores have defective coats which are missing several proteins. We have extended these studies with the finding that SafA and SpoVID were coimmunoprecipitated by anti-SafA or anti-SpoVID antiserum from whole-cell extracts 3 and 4 h after the onset of sporulation. Therefore, SafA may associate with SpoVID during the early stage of coat assembly. We used immunogold electron microscopy to localize SafA and found it in the cortex, near the interface with the coat in mature spores. SafA appears to have a modular design. The C-terminal region of SafA is similar to those of several inner spore coat proteins. The N-terminal region contains a sequence that is conserved among proteins that associate with the cell wall. This motif in the N-terminal region may target SafA to the PG-containing regions of the developing spore.

Glycine receptor (gephyrin) immunoreactivity is present on cholinergic neurons in the dorsal vagal complex

We previously demonstrated that microinjection of exogenous glycine into the nucleus tractus solitarii of anesthetized rats elicits responses that are qualitatively like those elicited by microinjection of acetylcholine at the same site. The responses to glycine, like those to acetylcholine, are blocked by administration of a muscarinic receptor antagonist and prolonged by administration of an acetylcholinesterase inhibitor. Furthermore, glycine leads to release of acetylcholine from the nucleus tractus solitarii and surrounding dorsal vagal complex. An anatomical framework for interactions between glycinergic and cholinergic neurons was established by studies that identified glycine terminals and receptors in the dorsal vagal complex. The current study investigated the relationship between glycine receptors and neuronal elements that were immunoreactive for choline acetyltransferase in the dorsal vagal complex. Neurons that were immunoreactive for choline acetyltransferase were located in the dorsal motor nucleus of the vagus, hypoglossal nucleus and nucleus ambiguus, and stained cells were also present in medial, intermediate, and ventrolateral subnuclei of the nucleus tractus solitarii. We found that glycine receptors, immunolabeled with an antibody to gephyrin, were present on cholinergic dendrites in the nucleus tractus solitarii. Gephyrin immunoreactivity was also present on dendrites that did not stain for choline acetyltransferase. These data further support the contribution of cholinergic neurons in mediating cardiovascular responses to glycine in the nucleus tractus solitarii.

Long glutamine tracts cause nuclear localization of a novel form of huntingtin in medium spiny striatal neurons in HdhQ92 and HdhQ111 knock-in mice

Huntington's disease (HD) is caused by an expanded N-terminal glutamine tract that endows huntingtin with a striatal-selective structural property ultimately toxic to medium spiny neurons. In precise genetic models of juvenile HD, HdhQ92 and HdhQ111 knock-in mice, long polyglutamine segments change huntingtin's physical properties, producing HD-like in vivo correlates in the striatum, including nuclear localization of a version of the full-length protein predominant in medium spiny neurons, and subsequent formation of N-terminal inclusions and insoluble aggregate. These changes show glutamine length dependence and dominant inheritance with recruitment of wild-type protein, critical features of the altered HD property that strongly implicate them in the HD disease process and that suggest alternative pathogenic scenarios: the effect of the glutamine tract may act by altering interaction with a critical cellular constituent or by depleting a form of huntingtin essential to medium spiny striatal neurons.

Phylogenetic and phenotypic diversity of 4-chlorobenzoate-degrading bacteria isolated from soils

Twenty numerically dominant 4-chlorobenzoate (4-CBA)-degrading bacteria were isolated from agricultural soils. The isolates were able to utilize 4-CBA as a sole source of carbon and energy. A total of 65% of the isolates was identified to the species level by fatty acid methyl ester (FAME) analysis, and the isolates were strains of Micrococcus, Pseudomonas, Oerskovia, Cellulomonas, and Arthrobacter species. The chromosomal DNA patterns of the isolates obtained by polymerase chain reaction (PCR) amplification of repetitive extragenic palindromic (REP) sequences were distinct from each other. Most of the isolates grew rapidly in 4-CBA medium, but their substrate utilization capabilities were generally restricted. Plasmid DNAs were detected from 55% of the isolates, and one strain, HR7, was shown to have self-transmissible, 4-CBA degradative plasmids. 4-CBA degradative enzymes were inducible by the presence of 4-CBA and most of the isolates appeared to mineralize it through 4-hydroxybenzoate rather than 4-chlorocatechol.

Expression of apoptosis regulatory genes in chronic cyclosporine nephrotoxicity favors apoptosis

Expression of apoptosis regulatory genes in chronic cyclosporine nephrotoxicity favors apoptosis.

BACKGROUND

Chronic cyclosporine (CsA) nephrotoxicity is characterized by interstitial fibrosis, tubular dropout, and loss of cellularity in areas of fibrosis. Apoptosis was found to play a role in CsA-induced fibrosis. We evaluated the role of the death genes p53, Bax, and Fas-L (ligand), survival gene Bcl-2, interleukin-converting enzyme (ICE), and caspase-3.

METHODS

Salt-depleted rats were administered CsA 15 mg/kg/day or vehicle (VH) and were sacrificed at 7 or 28 days. Apoptosis was detected by TdT-mediated dUTP-biotin nick end labeling assay. p53 and Bax expressions were evaluated by Northern and Western blot analysis. Fas-L and Bcl-2 expressions were evaluated by immunofluorescence. In addition to ICE mRNA, caspase-3 enzymatic activity was assayed.

RESULTS

Although no differences were seen at one week, apoptosis-positive cells increased with CsA at four weeks (P < 0.05) and correlated with tubular atrophy and interstitial fibrosis (r = 0.8, P < 0.05). CsA induced the expression of p53 (P < 0.05) and Bax (P < 0.01) and decreased that of Bcl-2 (P < 0.05). CsA up-regulated Fas-L expression (P < 0.001). ICE mRNA and caspase-3 activity were also increased (P < 0.01). The changes occurred as early as one week and remained statistically significant at four weeks.

CONCLUSIONS

Specific apoptotic genes are increased in chronic CsA nephrotoxicity. The balance favors the induction of apoptosis. Increased apoptosis could explain the tubular dropout and loss of cellularity with fibrosis. This then may impair the ability of the tubulointerstitium to remodel. Apoptosis could also contribute to some of CsA immunosuppressive effects on activated lymphocytes.

[A study on hemostatic and immunological actions of fresh and dry Dihuang]

OBJECTIVE

To investigate the difference between fresh and dry Dihuang (Radix Rehmanniae) in hemostatic and immunological actions.

METHODS

The hemostatic action was assessed in aspirin-treated mice; immunological action was assessed by phagocytosis of macrophages in dexamethasone-treated mice; and Con A-induced mitogenesis and LPS-induced alkaline phosphatase activity of splenocytes were determined in thyroxin-treated mice.

RESULT

The blood clotting in mice induced by aspirin was inhibited by oral administrations of juice decoction of fresh Dihuang or decoction of dry Dihuang alike. The action of fresh Dihuang juice was stronger than that of dry Dihuang decoction. Oral administrarion of fresh Dihuang juice or decoction for 10 days enhanced LPS-induced alkaline phosphatase activity of splenocytes in thyroxin-treated mice. The juice also enhanced Con A-induced splenocyte mitogenesis. The action of dry Dihuang decoction was weaker than that of fresh juice in increasing LPS-induced alkaline phosphatase activity.

CONCLUSION

It is recommended to follow the tradition of using fresh Dihuang juice or decoction to treat some diseases such as hemorrhagenic troubles.

Phytochrome signalling is mediated through nucleoside diphosphate kinase 2

Because plants are sessile, they have developed intricate strategies to adapt to changing environmental variables, including light. Their growth and development, from germination to flowering, is critically influenced by light, particularly at red (660 nm) and far-red (730 nm) wavelengths. Higher plants perceive red and far-red light by means of specific light sensors called phytochromes(A-E). However, very little is known about how light signals are transduced to elicit responses in plants. Here we report that nucleoside diphosphate kinase 2 (NDPK2) is an upstream component in the phytochrome signalling pathway in the plant Arabidopsis thaliana. In animal and human cells, NDPK acts as a tumour suppressor. We show that recombinant NDPK2 in Arabidopsis preferentially binds to the red-light-activated form of phytochrome in vitro and that this interaction increases the activity of recombinant NDPK2. Furthermore, a mutant lacking NDPK2 showed a partial defect in responses to both red and farred light, including cotyledon opening and greening. These results indicate that NDPK2 is a positive signalling component of the phytochrome-mediated light-signal-transduction pathway in Arabidopsis.

Mitogen-activated protein kinase pathway mediates peroxynitrite-induced apoptosis in human dopaminergic neuroblastoma SH-SY5Y cells

Peroxynitrite, a product of nitric oxide and superoxide, is one of the most potent oxidants and it has been suggested to be involved in many neurodegenerative disorders. The mechanism of the cytotoxicity by peroxynitrite was examined using 3-morpholinosydonimine (SIN-1) as a peroxynitrite donor and SH-SY5Y cells as a model of dopamine neurons. SIN-1 was found to induce apoptotic cell death with typical nucleosomal DNA fragmentation with activation of caspase 3-like proteases. The signal transduction of apoptosis was studied in concern to mitogen-activated protein kinases (MAPKs). After SIN-1 treatment, phosphorylation of p38 was detected, followed by that of Erk. SB202190, an inhibitor of p38, suppressed Erk phosphorylation to the basal level and partially reduced the activation of caspase 3-like proteases and also the cell death. These results suggest that peroxynitrite may activate p38 MAPK pathway to induce apoptosis in dopamine cells via activation of caspase 3-like proteases.

[Determination of C1-C5 composition of liquefied petroleum gas by capillary gas chromatography]

In this paper, thirteen C1-C5 hydrocarbons in liquefied petroleum gas were separated and determined by using capillary gas chromatography. The cloumn used was 50 m x 0.53 mm i.d. HP PLOT-Al2O3. A standard mixture of known composition was used for the determination of correction factots and the corrected area mormalization was used for quantification. The relative standard deviations (n = 5) were 0.39%-5.4%. Ethane, ethylene and butene were separated to baseline.

Cymbidium hybrida dihydroflavonol 4-reductase does not efficiently reduce dihydrokaempferol to produce orange pelargonidin-type anthocyanins

Some angiosperms are limited to a range of possible flower colors. This limitation can be due to the lack of an anthocyanin biosynthetic gene or to the substrate specificity of a key anthocyanin biosynthetic enzyme, dihydroflavonol 4-reductase (DFR). Cymbidium hybrida orchid flowers primarily produce cyanidin-type (pink to red) anthocyanins and lack the pelargonidin-type (orange to brick-red) anthocyanins. To investigate the underlying molecular mechanism of this flower color range, we cloned a Cymbidium DFR gene and transformed it into a DFR- petunia line. We found that the Cymbidium DFR did not efficiently reduce dihydrokaempferol (DHK), which is an essential step for pelargonidin production. Phylogenetic analysis of a number of DFR sequences indicate that the inability to catalyze DHK reduction has occurred at least twice during angiosperm evolution. Our results indicate that developing a pelargonidin-type orange flower color in Cymbidium may require the transformation of a DFR gene that can efficiently catalyze DHK reduction.

Nuclear and neuropil aggregates in Huntington's disease: relationship to neuropathology

The data we report in this study concern the types, location, numbers, forms, and composition of microscopic huntingtin aggregates in brain tissues from humans with different grades of Huntington's disease (HD). We have developed a fusion protein antibody against the first 256 amino acids that preferentially recognizes aggregated huntingtin and labels many more aggregates in neuronal nuclei, perikarya, and processes in human brain than have been described previously. Using this antibody and human brain tissue ranging from presymptomatic to grade 4, we have compared the numbers and locations of nuclear and neuropil aggregates with the known patterns of neuronal death in HD. We show that neuropil aggregates are much more common than nuclear aggregates and can be present in large numbers before the onset of clinical symptoms. There are also many more aggregates in cortex than in striatum, where they are actually uncommon. Although the striatum is the most affected region in HD, only 1-4% of striatal neurons in all grades of HD have nuclear aggregates. Neuropil aggregates, which we have identified by electron microscopy to occur in dendrites and dendritic spines, could play a role in the known dendritic pathology that occurs in HD. Aggregates increase in size in advanced grades, suggesting that they may persist in neurons that are more likely to survive. Ubiquitination is apparent in only a subset of aggregates, suggesting that ubiquitin-mediated proteolysis of aggregates may be late or variable.

[Comparing Swerita daridi with Swertia mileencis on pharmacologic action]

The article compared Swertia daridi with Swertia mileencis about chemical composition and pharmacological action. The study showed two species drug's bitter taste chemical composition and pharmacological action are approximately equal. It can be tried to replace Swertia daridi with Swertia mileencis.

Ataxin-1 nuclear localization and aggregation: role in polyglutamine-induced disease in SCA1 transgenic mice

Transgenic mice carrying the spinocerebellar ataxia type 1 (SCA1) gene, a polyglutamine neurodegenerative disorder, develop ataxia with ataxin-1 localized to aggregates within cerebellar Purkinje cells nuclei. To examine the importance of nuclear localization and aggregation in pathogenesis, mice expressing ataxin-1[82] with a mutated NLS were established. These mice did not develop disease, demonstrating that nuclear localization is critical for pathogenesis. In a second series of transgenic mice, ataxin-1[77] containing a deletion within the self-association region was expressed within Purkinje cells nuclei. These mice developed ataxia and Purkinje cell pathology similar to the original SCA1 mice. However, no evidence of nuclear ataxin-1 aggregates was found. Thus, although nuclear localization of ataxin-1 is necessary, nuclear aggregation of ataxin-1 is not required to initiate pathogenesis in transgenic mice.

The cellular and subcellular localization of huntingtin-associated protein 1 (HAP1): comparison with huntingtin in rat and human

The cellular and subcellular distribution of HAP1 was examined in rat brain by light and electron microscopic immunocytochemistry and subcellular fractionation. HAP1 localization was also determined in human postmortem tissue from control and Huntington's disease (HD) cases by light microscopic immunocytochemistry. At the cellular level, the heterogeneity of HAP1 expression was similar to that of huntingtin; however, HAP1 immunoreactivity was more widespread. The subcellular distribution of HAP1 was examined using immunogold electron microscopy. Like huntingtin, HAP1 is a cytoplasmic protein that associates with microtubules and many types of membranous organelles, including mitochondria, endoplasmic reticulum, tubulovesicles, endosomal and lysosomal organelles, and synaptic vesicles. A quantitative comparison of the organelle associations of HAP1 and huntingtin showed them to be almost identical. Within HAP1-immunoreactive neurons in rat and human brain, populations of large and small immunoreactive puncta were visible by light microscopy. The large puncta, which were especially evident in the ventral forebrain, were intensely HAP1 immunoreactive. Electron microscopic analysis revealed them to be a type of nucleolus-like body, which has been named a stigmoid body, that may play a role in protein synthesis. The small puncta, less intensely labeled, were primarily mitochondria. These results indicate that the localization of HAP1 and huntingtin is more similar than previously appreciated and provide further evidence that HAP1 and huntingtin have localizations consistent with roles in intracellular transport. Our data also suggest, however, that HAP1 is not present in the abnormal intranuclear and neuritic aggregates containing the N-terminal fragment of mutant huntingtin that are found in HD brains.

The herbal medicine Sho-saiko-to inhibits growth and metastasis of malignant melanoma primarily developed in ret-transgenic mice

Sho-saiko-to is the most popular herbal medicine in Japan. We investigated the anti-tumor and anti-metastatic effects of Sho-saiko-to and its chemically defined ingredients on the primary skin melanoma that developed in a metallothionein-I (MT)/ret transgenic mouse line and on a melanoma cell line (Mel-ret), which was derived from a primary tumor developed in a MT/ret transgenic mouse. In vitro, Sho-saiko-to suppressed the growth of Mel-ret cells more strongly than any single ingredient of Sho-saiko-to, although baicalin as one of several ingredients tested also suppressed it significantly. In vivo, Sho-saiko-to (i) significantly (p < 0.02) prolonged the onset of tumor development (1.5 mo), (ii) definitely retarded the transition to malignancy, (iii) significantly decreased the incidence of distant metastasis to brain (p < 0.002), kidney (p < 0.05), and liver (p < 0.05) at the malignant stage, and (iv) significantly (p < 0.02) prolonged life span (2.6 mo). Moreover, Sho-saiko-to and baicalin down-regulated the matrix metalloproteinase-2 and -9 expression levels, and upregulated their inhibitor expression level in both the primary tumors and Mel-ret cells. In conclusion, Sho-saiko-to displayed anti-tumor and anti-metastatic effects on melanoma with regulation of the balance of matrix metalloproteinase and tissue inhibitor of the matrix metalloproteinase levels.

Distribution and developmental regulation of metabotropic glutamate receptor 7a in rat brain

To determine the regional and cellular distribution of the metabotropic glutamate receptor mGluR7a, we used rabbit anti-peptide polyclonal-targeted antibodies against the C-terminal domain of mGluR7a. Here we report that immunocytochemistry at the light-microscopic level revealed that mGluR7a is widely distributed throughout the adult rat brain, with a high level of expression in sensory areas, such as piriform cortex, superior colliculus, and dorsal cochlear nucleus. In most brain structures, mGluR7a immunoreactivity is characterized by staining of puncta and fibers. However, in some regions, including the locus ceruleus, cerebellum, and thalamic nuclei, both cell bodies and fibers are immunopositive. The changes in levels of mGluR7a during development were investigated with immunoblotting and immunocytochemical analysis. Immunoblot analysis revealed that the levels of mGluR7a are differentially regulated across brain regions during postnatal development. In cortical regions (hippocampus, neocortex, and olfactory cortex), mGluR7a levels were highest at postnatal day 7 (P7) and P14, then declined in older rats. In contrast, mGluR7a levels were highest at P7 in pons/medulla and cerebellum and decreased markedly between P7 and P14. In these regions, mGluR7a immunoreactivity was at similar low levels at P14 and P21 and in adults. Immunocytochemical analysis revealed that staining for mGluR7a was exceptionally high in fiber tracts in P7 animals relative to adults. Furthermore, the pattern of mGluR7a immunoreactivity in certain brain structures, including cerebellum, piriform cortex, and hippocampus, was significantly different in P7 and adult animals. In summary, these data suggest that mGluR7a is widely distributed throughout the rat brain and that this receptor undergoes a dynamic, regionally specific regulation during postnatal development.

Processing of delta-endotoxin of Bacillus thuringiensis subsp. kurstaki HD-1 in Heliothis armigera midgut juice and the effects of protease inhibitors

Bombyx mori was found to be more sensitive to the protoxins of HD-1 than Heliothis armigera. SDS-PAGE analysis showed that a large amount of activated toxin was yielded from protoxin by B. mori gut juice while little was yielded by H. armigera. Further degradation of activated toxin was observed in H. armigera midgut juice detected by SDS-PAGE. pH influenced the proteolytic activity of the midgut juice significantly, but there was no obvious effect of pH on the degradation of activated toxin. Specific inhibitor study revealed the presence of trypsin, chymotrypsin, and elastase in the midgut juice. TLCK, TPCK, elastatinal and some general serine protease inhibitors successfully prevented the excessive degradation of protoxin in H. armigera midgut juice. Chymotrypsin inhibitors showed strong inhibitory effects against the further degradation of activated toxin, indicating that chymotrypsin played a major role in the process. It was presumed that the excessive degradation of protoxin in H. armigera midgut juice was responsible for the low sensitivity of the insect to Bt. Further study demonstrated that the excessive degradation in vitro was triggered by SDS treatment. However, all of the tested serine protease inhibitors expressed synergism with protoxin against H. armigera larvae, suggesting that the excessive degradation of protoxin may occur in vivo to some extent and may be triggered by receptor binding of activated toxin.

[Observation on inhibitory effect of Coptis alone and its combination with Scutellaria and Liquorice on the growth of Staphylococcus aureus]

Using MIC as relative index, an observation was made on the growth inhibition of Staphylococcus aureus by Coptis alone or in combination with Scutellaria and or liquorice. The result shows that when Coptis is combined with Scutellaria, the bacteriostatic effect gets weaker for Scutellaria, but remains unchanged for Coptis, and when Scutellaria takes greater percentages in the combination, the effect of Coptis seems to be stronger. When Coptis is combined with liquorice, whatever the respective percentages may be, the effect tends to get weaker. When the three drugs are used in combination, the effect remains unchanged or even gets stronger for Coptis or liquorice, but tends to decrease for Scutellaria. Coptis used singly or in combination with Scutellaria or liquorice is inferior in bacteriostatic effect to the combination of the three drugs. The mechanism is yet to be further studied.

Minimal residual disease after intensive induction therapy in childhood acute lymphoblastic leukemia predicts outcome

We investigated the level of minimal residual disease (MRD) in 26 children with B-lineage acute lymphoblastic leukemia (ALL) after intensive induction therapy. A quantitative semi-nested polymerase chain reaction (PCR) detecting the clone-specific rearranged immunoglobulin heavy chain genes was developed to improve sensitivity and specificity of amplification. In all patients, one leukemic cell could be detected in a background of 10(5) normal blood mononuclear cells. All patients investigated were in complete remission at the end of induction therapy as evaluated by morphologic criteria. Nineteen patients (73%) had no detectable residual leukemic cells using the sensitive semi-nested PCR. Seven patients (27%) were PCR positive. Three had a low level (<2 x 10(-5) leukemic cells per bone marrow cell), while four patients had a high level (>2 x 10(5)) of detectable residual leukemic cells. All patients with low or undetectable levels of residual leukemia remained in complete remission at a median of 63 months from diagnosis (range 40-80 months), while all four patients with a high level of residual leukemia subsequently relapsed at a median of 21 months from diagnosis (range 13-37 months). The patient groups with undetectable or low, and high level of MRD did not differ significantly in other clinical or genetic features with prognostic significance. We conclude that the level of MRD at the end of the intensive induction therapy period is predictive of outcome in childhood B lineage ALL. If confirmed by large prospective studies, the level of MRD might be useful in stratifying patients into high and low risk categories.

Subcellular localization and molecular topology of the dopamine transporter in the striatum and substantia nigra

Plasma membrane transporters remove neurotransmitters from the extracellular space and have been postulated to terminate synaptic activity. Their specific roles in synaptic and nonsynaptic neurotransmission at a cellular level, however, remain unclear. We have determined the subcellular location of the dopamine transporter (DAT) by immunoperoxidase and immunogold electron microscopy, using monoclonal antibodies to both the N-terminus and the second extracellular loop. The two DAT epitopes were found on opposite faces of cellular and intracellular membranes, providing confirmation of the predicted molecular topology of DAT. In the striatum, DAT was localized in the plasma membrane of axons and terminals. Double immunocytochemistry demonstrated DAT colocalization with two other markers of nigrostriatal terminals, tyrosine hydroxylase and D2 dopamine receptors. The latter was thus demonstrated to be an autoreceptor. Labeled striatal terminals formed symmetrical synapses with spines, dendrites, and perikarya. DAT was not identified within any synaptic active zones, however, even using serial section analysis. These results suggest that striatal dopamine reuptake may occur outside of synaptic specializations once dopamine diffuses from the synaptic cleft. In the substantia nigra, DAT appears to be specifically transported into dendrites, where it can be found in smooth endoplasmic reticulum, plasma membrane, and pre- and postsynaptic active zones. These localizations suggest that DAT modulates the intracellular and extracellular dopamine levels of nigral dendrites. Within the perikarya of pars compacta neurons, DAT was localized primarily to rough and smooth endoplasmic reticulum, Golgi complex, and multivesicular bodies, identifying probable sites of synthesis, modification, transport, and degradation.

Differential sensitivities to hyperbaric oxygen of lymphocyte subpopulations of normal and autoimmune mice

We studied the effect of exposure to hyperbaric oxygen (HBO): 2.8 atm absolute 100% oxygen for 4 h daily over 3-7 days, on the immune system of normal (BALB/c and MRL- +/+) and autoimmune MRL-lpr/lpr) mice. In HBO exposed BALB/c mice, we observed a remarkable decrease in the cell population of the spleen and thymus. We found that the sensitivity to HBO varied among subpopulations of lymphocytes. For example, CD4+ CD8+ double positive cells in the thymus and B220+ B cells in the spleen were more sensitive than CD4+ or CD8+ single positive T cells in the thymus, and Thy-1+ T cells in the spleen, respectively. Accordingly, despite the decrease in total cell number in the spleen, the proliferative response of T cells from the spleen to Con A was not impaired in the HBO exposed mice. Exposure of MRL-lpr/lpr mice to HBO caused a marked reduction of weight and cell population of the otherwise enlarged spleen and lymph nodes, and amongst others of percentages of B220+Thy-1+ double positive abnormal cells. These results suggest the HBO therapy may be applicable for the treatment of some autoimmune diseases.

Pallidal afferent territory of the Macaca mulatta thalamus: neuronal and synaptic organization of the VAdc

Ventral anterior thalamic nucleus pars densicellularis (VAdc) as delineated earlier (Ilinsky and Kultas-Ilinsky [1987] J. Comp. Neurol. 262:331-364) was analyzed by using qualitative and quantitative neuroanatomical techniques. Projection neurons (PN), retrogradely labeled with wheat germ agglutinin conjugated horseradish peroxidase from the cortex, were small to medium in size (mean area, 312 microm2) with numerous primary dendrites displaying a tufted branching pattern. Local circuit neurons (LCN), immunoreactive for gamma-aminobutyric acid (GABA) and glutamic acid decarboxylase, were small (mean area, 110 microm2), and gave off few dendrites. Two subpopulations of GABA positive boutons (F1 type) were distinguished: large (mean area, 2.6 microm2) terminals with symmetric synapses containing few pleomorphic vesicles and numerous mitochondria densely covered proximal PN sites; smaller F1 boutons with a slightly different morphology contacted mostly distal PN dendrites. Two subpopulations of terminals containing round vesicles and forming asymmetric synapses were distinguished by bouton size (mean areas, 0.4 microm2 and 1.6 microm2, respectively). These targeted mainly distal PN dendrites, but some synapsed proximally next to large F1 boutons. On distal dendrites, representatives of both types were labeled from the cortex. The density of boutons with symmetric and asymmetric synapses (the number of boutons per 100 microm of PN membrane length) was 3.3:0.2 on primary, 2.5:1.2 on secondary, and 0.8:12 on distal dendrites. The numerical density of synapses formed by presynaptic LCN dendrites on all PN levels was 20 to 40 times less than that of axon terminals at the same sites. Afferent input to LCN from boutons of all types, including that from 50% of labeled cortical boutons, mainly targeted distal dendrites. Overall, the findings suggest that PN in VAdc receive massive inhibitory input proximally intermingled with some presumably excitatory input, and that LCN contribution to PN inhibition is modest.

Mode of termination of pallidal afferents to the thalamus: a light and electron microscopic study with anterograde tracers and immunocytochemistry in Macaca mulatta

The mode of termination of individual pallidothalamic fibers in the densicellular subdivision of the ventral anterior thalamic nucleus (VAdc) of Macaca mulatta was analyzed with light and electron microscopy after injections of anterograde tracers in the medial globus pallidus. Three tracers were utilized: tritiated leucine, biotinylated dextran amine, and wheat germ agglutinin conjugated to horseradish peroxidase in combination with postembedding immunocytochemsitry for gamma-aminobutyric acid (GABA). Pallidothalamic fibers, upon entering the VAdc, gave off several collaterals that formed plexuses of varicose terminal branches within different cell clusters. The varicosities were aligned along somata and proximal dendrites of projection neurons providing dense input to each individual cell. At the electron microscopic level, labeled boutons displayed a predominantly flat and elongated shape. They contained a moderate number of pleomorphic synaptic vesicles and very large amounts of mitochondria, displayed symmetric synaptic contacts, and were immunoreactive for GABA. In the total sample of 128 autoradiographically labeled terminals, 64% were in synaptic contact with somata and primary dendrites of projection neurons, 14% formed synapses on proximal dendrites of undefined order, and only 7% established synaptic contacts on distal dendrites. Fifteen percent of the labeled boutons established synapses on distal dendrites of GABAergic local circuit neurons (LCN). Pallidal boutons were also found in complex synaptic arrangements: triads with three GABAergic synapses, and serial synapses with LCN dendrites that in turn established synaptic contacts on projection neuron somata or dendrites. These anatomical results suggest a dual effect of pallidal afferents to projection neurons: direct inhibition and disinhibition mediated by LCN. The findings indicate that the fine structure of pallidothalamic terminals in the monkey is similar to that described earlier in the cat. There are, however, interspecies differences in the distribution of pallidal input on postsynaptic targets and its participation in complex synaptic arrangements.

Actin Filaments Modulate Both Stomatal Opening and Inward K+-Channel Activities in Guard Cells of Vicia faba L

Actin antagonists have previously been shown to alter responses of Commelina communis stomata to physiological stimuli, implicating actin filaments in the control of guard cell volume changes (M. Kim, P.K. Hepler, S.-O. Eun, K.S. Ha, Y. Lee [1995] Plant Physiol 109: 1077-1084). Since K+ channels in the guard cell play an important role in stomatal movements, we examined the possible regulation of K+-channel activities by the state of actin polymerization. Agents affecting actin polymerization altered light-induced stomatal opening and inward K+-channel activities measured by patch clamping in Vicia faba. Cytochalasin D, which induces depolymerization of actin filaments, promoted light-induced stomatal opening and potentiated the inward K+ current in guard cell protoplasts. Phalloidin, a stabilizer of filamentous actin, inhibited both light-induced stomatal opening and inward K+ current. Inward K+-channel activities in outside-out membrane patches showed responses to these agents that support results at the whole-cell current level, suggesting that cytochalasin D facilitates and phalloidin inhibits K+ influx in intact guard cells, thus resulting in enhancement and inhibition of stomatal opening, respectively. To our knowledge, this is the first report that provides evidence that actin filaments may regulate an important physiological process by modulating the activities of ion channels in plant cells.

Protein kinase C alpha-mediated chronic signal transduction for immunosenescence

In CD2/protein kinase C alpha (PKC alpha)-overexpressing human CD2/rabbit PKC alpha transgenic mice, an aging-dependent increase in PKC alpha expression and a decrease in proliferative responsiveness of splenic T cells were promoted. We found that an aging-associated accumulation of CD44(high) CD45RB(low) memory CD4+ T cells in exchange for CD44(low) CD45RB(high) naive CD4+ T cells was promoted in transgenic mice. A disequilibrium between Ag-dependent generation and subsequent elimination of memory T cells in these mice was shown to underlie this phenomenon. When stimulated with Ag, the PKC alpha transgenic mice responded poorly regarding Ab production and produced cytokines biased for high IFN-gamma/IL-12 and low IL-4/IL-10 levels. These results prove, for the first time, a causal role for chronic signal transduction through PKC alpha in aging-associated immunodysfunction and provide the first animal model for genetically promoted immunosenescence.

Protein kinase C alpha-mediated chronic signal transduction for immunosenescence

In CD2/protein kinase C alpha (PKC alpha)-overexpressing human CD2/rabbit PKC alpha transgenic mice, an aging-dependent increase in PKC alpha expression and a decrease in proliferative responsiveness of splenic T cells were promoted. We found that an aging-associated accumulation of CD44(high) CD45RB(low) memory CD4+ T cells in exchange for CD44(low) CD45RB(high) naive CD4+ T cells was promoted in transgenic mice. A disequilibrium between Ag-dependent generation and subsequent elimination of memory T cells in these mice was shown to underlie this phenomenon. When stimulated with Ag, the PKC alpha transgenic mice responded poorly regarding Ab production and produced cytokines biased for high IFN-gamma/IL-12 and low IL-4/IL-10 levels. These results prove, for the first time, a causal role for chronic signal transduction through PKC alpha in aging-associated immunodysfunction and provide the first animal model for genetically promoted immunosenescence.

Inhibition of apoptosis by normal and aberrant Fli-1 and erg proteins involved in human solid tumors and leukemias

Two ets family members, namely erg and Fli-1 are fused with two EWS family members namely EWS and TLS/FUS as a result of chromosome translocation in human solid tumors and leukemias. EWS-erg and EWS-Fli-1, which are involved in greater than 95% of Ewing family of tumors, were shown to function as transcriptional activators. TLS/FUS-erg, which is involved in human myeloid leukemias also functions as a transcriptional activator. Expression of these fusion proteins (EWS-erg and EWS-Fli-1) are shown to be essential for maintaining the oncogenic and tumorigenic properties of tumor cells. Cancer is thought to be caused not only by uncontrolled cell proliferation but also by deregulation of programmed cell death. Therefore, we have studied the role of normal (Fli-1 and erg) and aberrant fusion proteins (EWS-erg, EWS-Fli-1 and TLS/FUS-erg) in apoptosis. We have found that expression of normal (Fli-1 and erg) and aberrant fusion proteins inhibit the apoptosis of NIH3T3 cells induced by either serum deprivation or by treatment with calcium ionophore. We have also observed similar suppression of apoptosis in Ewing's sarcoma cells expressing EWS-Fli-1 and EWS-erg proteins suggesting that these fusion proteins may be responsible for the decreased ability of these tumor cells to undergo apoptosis. Inhibition of the expression of these aberrant fusion proteins by antisense RNA technique resulted in increased susceptibility to apoptosis leading to the death of tumor cells. Therefore, our results suggest that one can use therapeutic agents which can down regulate the expression of fusion proteins in combination with chemotherapeutic agents as an effective treatment for these human solid tumors and leukemias.

Light and electron microscopic localization of presenilin-1 in primate brain

Several genes have been implicated in the pathogenesis of early-onset familial Alzheimer's disease. A majority of the autosomal dominant cases are linked to recently identified mutations in the presenilin-1 gene on chromosome 14. The native presenilin-1 protein in primates has not been well characterized, and its precise localization is unknown. We have studied the native presenilin-1 protein in monkey brain and peripheral tissues by using a monoclonal antibody specific for the N-terminal domain of human presenilin-1. Western blots detect polypeptide species of approximately 49 and approximately 32 kDa from COS-7 and PC12 cells transfected with full-length human presenilin-1 cDNA and from in vitro translations of the normal human presenilin-1 mRNA. A 32 kDa polypeptide is detected in monkey peripheral tissues, with the highest expression in testis and lung. In all brain regions the 32 kDa band is the predominant form of presenilin-1, and it is found in particulate subfractions. Light microscopic immunocytochemistry reveals presenilin-1 staining in all brain regions, with the strongest labeling in neurons and neuropil. In addition, weaker immunoreactivity is also present in glia and blood vessels. Neuronal staining shows significant variability, with particularly intense labeling of certain cell types, including large neocortical and hippocampal pyramidal neurons, magnocellular basal forebrain neurons, brainstem motoneurons, and some populations of interneurons. By electron microscopic immunocytochemistry, highly selective presenilin-1 staining is seen on the cytoplasmic surfaces of membranous organelles, which suggest localization to the endoplasmic reticulum-Golgi intermediate compartment, a subdomain of the endoplasmic reticulum, and some coated transport vesicles.

Fragile X mental retardation protein: nucleocytoplasmic shuttling and association with somatodendritic ribosomes

Fragile X syndrome, a leading cause of inherited mental retardation, is attributable to the unstable expansion of a CGG-repeat within the FMR1 gene that results in the absence of the encoded protein. The fragile X mental retardation protein (FMRP) is a ribosome-associated RNA-binding protein of uncertain function that contains nuclear localization and export signals. We show here detailed cellular localization studies using both biochemical and immunocytochemical approaches. FMRP was highly expressed in neurons but not glia throughout the rat brain, as detected by light microscopy. Although certain structures, such as hippocampus, revealed a strong signal, the regional variation in staining intensity appeared to be related to neuron size and density. In human cell lines and mouse brain, FMRP co-fractionated primarily with polysomes and rough endoplasmic reticulum. Ultrastructural studies in rat brain revealed high levels of FMRP immunoreactivity in neuronal perikarya, where it is concentrated in regions rich in ribosomes, particularly near or between rough endoplasmic reticulum cisternae. Immunogold studies also provided evidence of nucleocytoplasmic shuttling of FMRP, which was localized in neuronal nucleoplasm and within nuclear pores. Moreover, labeling was observed in large- and small-caliber dendrites, in dendritic branch points, at the origins of spine necks, and in spine heads, all known locations of neuronal polysomes. Dendritic localization, which was confirmed by co-fractionation of FMRP with synaptosomal ribosomes, suggests a possible role of FMRP in the translation of proteins involved in dendritic structure or function and relevant for the mental retardation occurring in fragile X syndrome.

Semantic matching of pictures in schizophrenia: a cross-cultural ERP study

In this study the N400 of schizophrenics was compared with that of control subjects in a picture semantic-matching task. The comparison of N400 difference waveforms (subtraction of event-related potentials of congruent from those of incongruent trials) between control and patients was supplemented by separate analysis for congruent and incongruent trials. The N400 latency was delayed in patients. Also, the amplitude of N400 in the difference waveform was reduced in schizophrenics; however only congruent trials were different for patients (more negative) with respect to controls. This result is consistent with the hypothesis that schizophrenics use context poorly, but inconsistent with simple versions of the idea that associations are generally disinhibited in schizophrenia. Since the amplitudes of N400 and an auditory P300 were not correlated, a general processing deficit does not explain the results. Finally, by using picture matching, a cross-cultural comparison of N400 in schizophrenics from Cuba and China was possible, which indicated that the N400 abnormalities were similar in both groups.

Murine model of cancer gene therapy

In order to examine how the adenovirus-mediated gene therapy induce anti-adenoviral immunity, we set up experiments for a murine cancer model. We first administered adenovirus carrying LacZ (AxCALacZ) gene to DBA/2 mice intraperitoneally, then two weeks after administration of the virus, P815 tumor cells infected with adenovirus carrying LacZ gene were inoculated intraperitoneally to the AxCALacZ immune mice. The mice rejected the P815 tumor infected with AxCALacZ and survived for long periods. The peritoneal T cells in adenovirus immune mice had a strong killing effect of adenovirus-infected P815 cells. Further, parental P815 tumor cells were inoculated into the mice, which rejected the P815 tumor infected with AxCALacZ. All mice rejected P815 tumor cells and survived for long periods. These mice developed P815 specific tumor immunity, which was confirmed by a cytotoxicity assay.

Expression of the putative vesicular acetylcholine transporter in rat brain and localization in cholinergic synaptic vesicles

A cholinergic locus has recently been identified consisting of a unique mammalian genomic arrangement containing the genes for choline acetyltransferase (ChAT) and a putative vesicular acetylcholine transporter (VAChT). Although transcripts for ChAT and VAChT protein have been localized in cholinergic neurons, little is known about the encoded VAChT protein. Here we describe production of highly specific rabbit polyclonal antibodies, generated using a VAChT C-terminus/glutathione-S-transferase fusion protein, and immunological characterization of the native VAChT protein. These antibodies specifically recognized full-length recombinant VAChT expressed in transfected HeLa cells by Western blotting, with the prominent immunoreactive band at 55 kDa. In rat brain homogenates, a single VAChT-immunoreactive band of approximately 70 kDa was predominant in known areas of cholinergic innervation, including striatum, cortex, hippocampus,and amygdala. Light microscopic immunocytochemistry revealed reaction product in cholinergic cell groups but not in noncholinergic areas. More significantly, immunoreactivity was also concentrated in axonal fibers in many regions known to receive prominent cholinergic innervation, such as cerebral cortex, hippocampus, amygdala, striatum, several thalamic nuclei, and brainstem regions. Electron microscopy using immunoperoxidase revealed that VAChT was localized in axon terminals, and using more precise immunogold techniques, to synaptic vesicles. In VAChT-positive perikarya, the immunogold particles were localized to the cytoplasmic face of the Golgi complex. These findings confirm that VAChT protein is expressed uniquely in cholinergic neurons, concentrated in synaptic vesicles, and at least for the C terminus, topologically oriented as predicted by models.

Efficient adenovirus-mediated gene transfer into human cancer cell lines derived from digestive tract

The efficiency of gene transfer into human cancer cells from digestive tract was evaluated using a replication-deficient recombinant adenovirus (Ad) vector harboring a lacZ gene of E. coli as a reporter gene (AxCALacZ). Average percent X-gal staining of esophageal cancer cell lines was 46%, that of gastric cancer cell lines 82% and that of colon cancer cell lines 70% at 3 days after Ad vector infection. X-gal staining in vitro continued 2 months after infection. By the direct injection of adenovirus vector to the tumors in nude mice, a certain percentage of tumor cells was stained by the X-gal. Colon26 cell line infected with AxCALacZ was implanted in BALB/c mice immunized with AxCALacZ, and tumor growth was suppressed. We presume this was due to anti-adenoviral immunity.

Calcineurin A alpha (PPP3CA), calcineurin A beta (PPP3CB) and calcineurin B (PPP3R1) are located on human chromosomes 4, 10q21-->q22 and 2p16-->p15 respectively

Calcineurin (also called protein phosphatase-2B) is a calmodulin-regulated protein phosphatase which plays an important role in signal transduction. The enzyme is a heterodimer of a 58-59 kDa calmodulin-binding catalytic subunit (calcineurin A) and a small (i.e. 19 kDa) Ca(2+)-binding regulatory subunit (calcineurin B). The highly conserved calcineurin B is encoded by a single gene in all tissues except testes, whereas there are three isoforms of calcineurin A (alpha, beta and gamma) encoded by genes on three different chromosomes. This enzyme can play a critical role in transcriptional regulation and growth control in T lymphocytes by a mechanism believed to involve dephosphorylation of the nuclear factor NF-AT which is essential for transcription of the interleukin-2 gene. To better evaluate the potential role of the calcineurin genes in human genetic disorders, we have studied their chromosome locations. Calcineurin B (PPP3R1) is located on human chromosome 2p16-->p15 and calcineurin A beta (PPP3CB, previous gene symbol CALNB) is present on 10q21-->q22. We confirm the localization of calcineurin A alpha (PPP3CA, previous gene symbol CALNA) to chromosome 4 without regional localization.

Enhancement of nitric oxide production from activated macrophages by glycyrrhizin

We studied the actions of glycyrrhizin on nitric oxide production from macrophages and a macrophage cell line RAW264-7. Although glycyrrhizin did not induce nitric oxide from resting macrophages, it enhanced the production of nitric oxide from IFN-gamma activated-macrophages or RAW cells. Glycyrrhizin also enhanced the production of nitric oxide from macrophages stimulated with the supernatant of con A-activated spleen cells. Further, glycyrrhizin enhanced tumor cell killing by macrophages activated with IFN-gamma. This tumor cell killing was mainly by nitric oxide.

Molecular basis for the management of secondary hyperparathyroidism in chronic renal failure

Recent clinical and experimental data suggest that the resistance of parathyroid cells to the physiological concentration of calcitriol plays an important role in the pathogenesis and the progression of secondary hyperparathyroidism in chronic renal failure. This resistance is due to the decreased density of the calcitriol receptor in parathyroid cells, which may result from impaired upregulation of calcitriol receptor. Since patients with larger parathyroid glands were more resistance to calcitriol pulse therapy than those with smaller glands and calcitriol receptor density inversely correlated with gland weight, the size of the parathyroid gland may serve as a marker for the degree of resistance to calcitriol. Furthermore, the possible role of phosphorus in the control of parathyroid function has been suggested recently. Thus, it is most important to prevent the progression of parathyroid hyperplasia in chronic renal failure by the early use of active vitamin D, calcitriol pulse therapy, and dietary phosphorus restriction.

Identification and localization of huntingtin in brain and human lymphoblastoid cell lines with anti-fusion protein antibodies

The Huntington disease (HD) phenotype is associated with expansion of a trinucleotide repeat in the IT15 gene, which is predicted to encode a 348-kDa protein named huntington. We used polyclonal and monoclonal anti-fusion protein antibodies to identify native huntingtin in rat, monkey, and human. Western blots revealed a protein with the expected molecular weight which is present in the soluble fraction of rat and monkey brain tissues and lymphoblastoid cells from control cases. In lymphoblastoid cell lines from juvenile-onset heterozygote HD cases, both normal and mutant huntingtin are expressed, and increasing repeat expansion leads to lower levels of the mutant protein. Immunocytochemistry indicates that huntingtin is located in neurons throughout the brain, with the highest levels evident in larger neurons. In the human striatum, huntingtin is enriched in a patch-like distribution, potentially corresponding to the first areas affected in HD. Subcellular localization of huntingtin is consistent with a cytosolic protein primarily found in somatodendritic regions. Huntingtin appears to particularly associate with microtubules, although some is also associated with synaptic vesicles. On the basis of the localization of huntingtin in association with microtubules, we speculate that the mutation impairs the cytoskeletal anchoring or transport of mitochondria, vesicles, or other organelles or molecules.

Multiphasic modulation of signal transduction into T lymphocytes by monoiodoacetic acid as a sulfhydryl reagent

Actions of monoiodoacetic acid (MIA) as a sulfhydryl reagent on the different stages of the T cell receptor (TCR)-mediated signal transduction were examined. MIA (1 mM) prevented anti-TCR (CD3) monoclonal antibody (mAb)-induced energy-dependent receptor capping but at the same time promoted the anti-CD3 mAb/mitogen-induced tyrosine phosphorylation of the T cell activation-linked cellular proteins of 120, 80, 70, 56, and 40 kDa. Relatively low concentration (0.01 mM) of MIA further promoted anti-CD3 mAb-induced transcription of c-fos, production of IL-2, and cell surface expression of IL-2 receptors. The MIA-promoted TCR-mediated IL-2 production actually required signal transduction that could be inhibited by cyclosporin A, genistein, or H-7. In contrast, the same concentration of MIA as promoted the signal transduction for cell activation severely inhibited the anti-CD3 mAb-triggered signal delivery for cell proliferation, selectively at its early stage. We conclude from these results that MIA differentially affects various steps of signaling into T lymphocytes, suggesting that there exist multiple sites of MIA-sensitive or redox-linked control in the signal cascade.

Electron microscopic analysis of D1 and D2 dopamine receptor proteins in the dorsal striatum and their synaptic relationships with motor corticostriatal afferents

The precise localization of D1 and D2 dopamine receptors within striatal neurons and circuits is crucial information for further understanding dopamine pharmacology. We have used subtype specific polyclonal and monoclonal antibodies against D1 and D2 dopamine receptors to determine their cellular and subcellular distributions, their colocalization, and their differential connectivity with motor cortical afferents labeled either by lesion-induced degeneration or by anterograde transport of biotinylated dextrans. D1 and D2 are primarily expressed in medium-sized neurons and spiny dendrites. Axon terminals containing D1 were rare whereas D2-immunoreactive axon terminals forming symmetrical synapses with dendrites and spines were common. In 2 microns sections, D1 was localized to 53% of neurons, and D2 to 48% of neurons, while mixing D1 and D2 antibodies labeled 78%. By electron microscopy, D1 was localized to 43% of dendrites and 38% of spines while D2 was localized to 38% of dendrites and 48% of spines. Combining D1 and D2 antibodies resulted in the labeling of 88.5% of dendrites and 92.6% of spines. Using different chromogens for D1 and D2, colocalization was not observed. Ipsilateral motor corticostriatal afferents were primarily axospinous and significantly more synapsed with D1 than D2-positive spines (65% vs 47%). Contralateral motor corticostriatal afferents were frequently axodendritic and no difference in their frequency of synapses with D1 and D2 dendrites and spines was observed. These findings demonstrate differential patterns of expression of D1 and D2 receptors in striatal neurons and axon terminals and their differential involvement in motor corticostriatal circuits.

Genomic organization and chromosomal localization of the DUSP2 gene, encoding a MAP kinase phosphatase, to human 2p11.2-q11

The mitogen-induced gene, DUSP2, encodes a nuclear protein, PAC1, that acts as a dual-specific protein phosphatase with stringent substrate specificity for MAP kinase. MAP kinase phosphorylation and consequent enzymatic activation is a central and often obligatory component in signal transduction initiated by growth factor stimulation or resulting from various types of oncogenic transformation. DUSP2 downregulates intracellular signal transduction through the dephosphorylation/inactivation of MAP kinases. To facilitate assessment of the possible role of DUSP2 in growth processes, the genomic structure and chromosomal location of the gene have been determined. DUSP2 has been localized to the pericentromeric region of human chromosome 2 (2p11.2-q11) by analysis of somatic cell hybrids, in situ chromosome hybridization, and genetic linkage analysis using a single-strand conformational polymorphism (SSCP) that has been identified in the 3' UTR of the gene. No consistent translocations or deletions at this chromosomal site have been reported in hematopoietic neoplasias or other tumors.

[The regulation of estradiol and progesterone in tumor necrosis factor production in vitro]

The production of tumor necrosis factor (TNF) induced by lipopolysaccharide (LPS) in peripheral blood mononuclear cells (PBMC) from normal woman were determined. The study investigated the role of regulation of estradiol (E2) and progesterone (P) in the production of TNF in-vitro. The results showed that PBMC would produce TNF when stimulated by E2 or P in culture in-vitro. The appropriate dosages were 125 pmol/L in E2 and 10-20 nmol/L in P. The findings suggested that some sex hormones could play a regulating role in the production of TNF by PBMC. E2 and P may be endogenous substances capable of inducing TNF production. The results revealed a beneficial aspect of sex hormones in anti-cancer treatment.

Bilateral herpes simplex virus type 2 keratitis: a clinicopathologic report with immunohistochemical and ultrastructural observations

This report describes the clinical, histopathologic, ultrastructural, and immunohistochemical findings in two corneal buttons from a 13-year-old girl who developed bilateral progressive corneal stromal opacification during childhood. As determined by light microscopy, both corneal buttons were edematous with a chronic inflammatory infiltrate confined to the deep layers of the stroma. We detected intranuclear eosinophilic inclusions in some epithelial cells. We detected herpesvirus particles in stromal keratocytes and endothelial cells by transmission electron microscopy. Immunohistochemistry studies identified concurrent expression of specific herpes simplex virus type 2 antigen in corneal epithelial cells, in keratocytes in the deep layers of the stroma, and in endothelial cells. The cause of progressive bilateral stromal corneal opacification in this child was herpes simplex virus type 2 keratitis. This condition should be considered in the differential diagnosis of progressive, bilateral corneal opacification in children.

Nucleus reticularis thalami input to the anterior thalamic nuclei in the monkey: a light and electron microscopic study

Three anterograde tracers (PHA-L, WGA-HRP, BDA) placed in the most dorsomedial segment of the anterior part of the nucleus reticularis thalami (NRT) in the Rhesus monkey combined with postembedding immunoctochemistry with anti-GABA antibody resulted in double labeling of a distinct population of synaptic boutons in the thalamic nuclei of the anterior group as well as laterodorsal and mediodorsal nuclei. EM analysis of the labeled terminals in the anteroventral and anteromedial parts of the anterior nuclear complex showed that the NRT input is distributed diffusely and in equal proportion to the dendrites of projection and local circuit neurons.

Promotion of cytotoxic T-cell generation in mixed leukocyte culture by phosphatidylinositol-specific phospholipase C from Bacillus thuringiensis

Phosphatidylinositol-specific phospholipase C (PIPLC) from Bacillus thuringiensis, which cleaves phosphatidylinositol or glycosylphosphatidylinositol on the external cell surface to generate a second messenger for intracellular signal transduction (S. Rahman et al., FEBS Lett. 303:193-196, 1992), was found to preferentially promote the generation of alloantigen-specific cytotoxic T lymphocytes in mixed leukocyte culture. PIPLC affected an early stage of cytotoxic T-lymphocyte activation in culture, and there was no evidence of any soluble cellular mediators of this PIPLC action. PIPLC neither enhanced overall cell proliferation nor noticeably promoted interleukin-2 and -4 production in mixed leukocyte culture. The relative population size of Ly-2+ T cells was increased, however, in a late mixed leukocyte culture with PIPLC. In addition, PIPLC enhanced an anti-CD3 monoclonal antibody-induced early increase in [Ca2+]i. These results suggest a new parasite (bacterium)-oriented mechanism for enhancing antigen-driven host cytotoxic T-lymphocyte immunity which does not include promotion of interleukin-2 production.

Nucleus reticularis thalami connections with the mediodorsal thalamic nucleus: a light and electron microscopic study in the monkey

Wheat germ agglutinin conjugated horseradish peroxidase (WGA-HRP) and biotinylated dextran amine (BDA) were used as tracers to study nucleus reticularis (NRT) connections with the mediodorsal nucleus (MD). Injections of WGA-HRP in the MD resulted in retrograde labeling of cells in the anteromedial segment of the NRT, the so-called rostral NRT pole. Injections of WGA-HRP and BDA in this NRT region resulted in dense anterograde labeling in the MD. Labeled NRT fibers gave off several collaterals to different MD regions ending with terminal plexuses of thin varicose fibers. In the neuropil, the varicosities were distributed at random, and no tendency to form pericellular baskets was noted. Postembedding immunocytochemistry for GABA was performed on the tissue containing anterograde WGA-HRP label for identification of NRT boutons under electron microscope. The double-labeled boutons were of small to medium size, contained a large number of pleomorphic vesicles, few mitochondria, and formed multiple symmetric synaptic contacts. The number of contacts established by one bouton ranged from 1 to 4 with an average of 1.8 per bouton. About 60% of these boutons made synapses on distal dendrites of GABAergic local circuit neurons; 33% of synaptic contacts were on distal dendrites of thalamocortical neurons, and the rest on their proximal dendrites and soma. NRT boutons were also found in serial synapses and triads. The results demonstrate that the NRT input to the MD is organized so that a single fiber innervates; different MD regions and its terminals form numerous synaptic contacts mostly on the distal dendrites of a large number of local circuit neurons and projection neurons.

Prevention of enhanced parathyroid hormone secretion, synthesis and hyperplasia by mild dietary phosphorus restriction in early chronic renal failure in rats: possible direct role of phosphorus

In order to evaluate the effect of dietary phosphorus (P) restriction on the pathogenesis of secondary hyperparathyroidism (2 degrees HPT) in chronic renal failure (CRF), we studied parathyroid function and parathyroid cell proliferation in 5/6 nephrectomized rats (CRF rats) fed with three different dietary P contents (0.6, 0.3 and 0.1%). Four weeks after 5/6 nephrectomy, serum immunoreactive parathyroid hormone (PTH) concentration, PTH mRNA level in parathyroid glands and the size of parathyroid glands were increased in CRF rats compared to those of sham-operated rats when both groups of rats were fed with normal P (0.6%) diet. These changes were not accompanied by any detectable changes of serum concentrations of calcium (Ca), inorganic phosphate (Pi) or calcitriol. In contrast, such evidence of 2 degrees HPT was obliterated in CRF rats fed with 0.3 or 0.1% P diet. In rats fed with 0.3% P diet, serum concentrations of Ca, Pi, and calcitriol were not different from those of sham-operated rats or from CRF rats fed with normal P diet. In contrast, serum Ca and calcitriol concentrations increased and serum Pi decreased in CRF rats fed with 0.1% P diet. These data suggest that 2 degrees HPT can be completely prevented at the levels of PTH secretion, synthesis and parathyroid cell proliferation by mild dietary P restriction (0.3%) alone, and that such effects may not depend upon the changes in serum concentrations of Ca, Pi or calcitriol, but may depend on reduced dietary P content per se. Thus, mild dietary P restriction from the early stage of CRF may be clinically effective for the prevention of 2 degrees HPT.

"Fenestrin" and conjugation in Tetrahymena thermophila

Certain monoclonal antibodies interact with proteins of Tetrahymena thermophila found in the conjugation junction as well as around the gametic nuclei (pronuclei) of conjugating cells; they also react with the oral primordium and fission zone of vegetative cells and with the cytoproct and contractile vacuole pores of all cells. One of these (FXIX-3A7) was investigated in detail. Immunogold labelling suggests that the material labelled by the 3A7 monoclonal antibody, which we call "fenestrin," is located beneath the epiplasm (membrane skeleton). Immunoblots reveal that the major and perhaps sole antigen is a 64 kDa polypeptide, found in two isoelectric variants. Developmental studies implicate fenestrin in two processes involved in conjugation. The first is "tip transformation." During preliminary starvation ("initiation"), labelling of fenestrin first appeared as a spot at the anterior end of starved mature cells, then after mixing of different mating types ("costimulation") it extended posteriorly along the anterior suture. After pairing, this region spread to form a widened plate. The second process is pronuclear transfer. Fenestrations representing channels between the conjugating cells began to appear 0.5 to 1 h after the conjugants united, and eventually merged to form a small number of temporary large holes during exchange of the transfer pronuclei. A fenestrin envelope also enclosed both the transfer and resident pronuclei; a strand of fenestrin connected the two. Shortly after pronuclear transfer, both transfer and resident pronuclei were released from fenestrin caps and fused to produce a zygotic nucleus (synkaryon) not associated with fenestrin Fenestrin thus appears to be intimately involved in the process of pronuclear exchange.