Induction of differentiation in embryonic stem cells by 26-kD membrane-bound tumor necrosis factor (TNF) and 17-kD free TNF

The biological activity of 26-kD membrane-bound tumor necrosis factor (TNF)-a in embryonal development was examined in an in vitro system using embryonic stem (ES) cells. ES cells were seeded on NIH3T3 feeder cells transformed with mouse precursor TNF-a gene to express membrane-bound TNF-a on their cell surface. The proliferation of the ES cells was reduced and differentiation was accelerated. The same effects were also observed when 17-kD free TNF-a was added to the culture medium of the ES cells. Since free TNF-a is not present during embryogenesis, these results suggest that membrane-bound TNF-a may play an important role in embryonal development through cell-cell contact.

Identification of actin as a substrate of ICE and an ICE-like protease and involvement of an ICE-like protease but not ICE in VP-16-induced U937 apoptosis

Human leukemia U937 cells are induced to undergo apoptosis by several chemotherapeutic agents; however, the cellular components involved in the process have not yet been identified. We found that an actin-cleavage activity (ACA) was activated in the VP-16-treated U937 cytosolic fraction and 15K- and 30K-actin fragments were produced. This ACA was inhibited by inhibitors of interleukin-1 beta-converting enzyme (ICE)/ced-3 family proteases, such as Z-Asp-CH2-DCB, YVAD-CHO, TPCK, TLCK, and iodoacetamide. Differing from ICE, the ACA could not process pro-IL-1 beta to mature IL-1 beta. Although ICE can cleave actin in vitro, ICE activity was not activated in the VP-16 treated U937 cells. These results indicate that actin is a potential substrate of ICE and ICE-like proteases, and that VP-16 preferentially activate an ICE-like protease, but not ICE itself, in U937 cells.

Molecular and crystal structures of two 1,6-anhydro-beta-maltotriose derivatives

Crystal structures of two 1,6-anhydro-beta-maltotriose derivatives, 1,6-anhydro-beta-maltotriose nonaacetate and 6"-bromo-6"-deoxy-1,6-anhydro-beta-maltotriose octaacetate, have been determined. Both structures are isomorphous and belong to the orthorhombic system, space group of P2(1)2(1)2(1), with cell dimensions of a = 15.659(3) A, b = 20.587(6) A, c = 13.023(2) A and a = 15.402(7) A, b = 19.737(8) A, c = 13.481(5) A, respectively. Each molecule has three alpha-(1-->4)-linked glucose units, and two of them have a typical 4C1 chair conformation, while the glucose unit with the 1,6-anhydro bridge has a 1C4 chair-envelope intermediate conformation. In spite of introducing the 1,6-anhydro bridge and acetyl groups, the conformations of the glycosidic linkages in these molecules are almost the same as those of other alpha-(1-->4)-linked oligosaccharides. Crystal structures are stabilized by hydrophobic interactions and by a weak intermolecular hydrogen bond of C-H. . .O.

Evaluation of cerebral infarction with iodine 123-iomazenil SPECT

This study evaluates ischemic damage to central benzodiazepine (BZD) receptor binding in the brain with [123]iomazenil SPECT in relation to CT hypodense lesions and blood flow abnormalities.

METHODS

Nine patients with middle cerebral artery territory infarction were studied. Iomazenil images obtained 180 min postinjection were analyzed for BZD receptor binding. The cortical infraction, visualized as CT hypodense area on CT, the peri-infarct area, visualized as normodensity surrounding the infarction on CT, the intrahemispheric remote area and the cerebellum were analyzed by taking the ratio of the lesion to contralateral mirror region (L/C ratio). CT during the chronic stage and perfusion images obtained during the smallest time difference between the two studies were used for comparative analysis.

RESULTS

The mean L/C ratio of iomazenil uptake was 0.53 +/_ 0.08, 0.79 +/- 0.07, 0.98 +/- 0.03 and 1.00 +/- 0.04 in the infarct, peri-infarct and remote areas and the cerebellum, respectively. The infarct and peri-infarct areas showed significant decrease compared with unity. The corresponding mean L/C ratio for blood flow was 0.52 +/- 0.08, 0.73 +/- 0.07, 0.83 +/- 0.09, and 0.80 +/- 0.07, respectively. In all areas, the ratios were significantly decreased compared with unity. There was significant difference between the L/C ratio for blood flow and iomazenil in the remote area and the cerebellum.

CONCLUSION

Iodine-123-iomazenil SPECT imaging may provide new information on ischemic damage to the brain, particularly neurons.

Carbon-11-methionine PET evaluation of intracerebral hematoma: distinguishing neoplastic from non-neoplastic hematoma

We evaluated whether PET with L-methyl-11C-methionine (11C-methionine) was clinically useful in distinguishing neoplastic from non-neoplastic intracerebral hematoma.

METHODS

We examined eight patients with neoplastic (n = 4) or non-neoplastic (n = 4) intracerebral hematomas between 5 and 68 days after the bleeding episode using PET with 11C-methionine (Met-PET).

RESULTS

Carbon-11-methionine accumulated in the area surrounding the hematoma in both groups, except in one patient with an acute hypertensive hematoma. Between 22 and 45 days after the ictus, non-neoplastic hematomas showed increased 11C-methionine accumulation largely in accordance with the contrast-enhanced areas on CT or MR images; whereas between 14 and 68 days after bleeding, neoplastic hematomas showed increased 11C-methionine accumulation that extended beyond the contrast-enhanced areas on CT or MR images. The intensity of 11C-methionine accumulation in tumor tissue was greater than that in non-neoplastic hematomas.

CONCLUSION

Preliminary results suggest that Met-PET can distinguish neoplastic from non-neoplastic hematomas on the basis of differences in lesion extent compared with CT or MR findings.

Correlation among secondary structure, amyloid precursor protein accumulation, and neurotoxicity of amyloid beta(25-35) peptide as analyzed by single alanine substitution

Structure-neurotoxicity relationships of amyloid beta (25-35) peptide were studied by replacing each amino acid with Ala. In contrast to the general tendency in hydrophobicity-toxicity relationships, replacement of Asn27 yielded a more hydrophobic but less toxic analog and that of Met35 gave a less hydrophobic but more toxic one. Sedimentation profiles and CD spectra indicated that peptide aggregation via intermolecular beta-sheet formation is essential for the neurotoxicity of amyloid beta (25-35) peptide. The correlation between neurotoxicity and amyloid precursor protein accumulation suggested that the latter is one of the pathways of the neuronal death caused by amyloid beta protein.

Interleukin-4 inhibits lak and initial phase til activity via interleukin-2 receptor

In the present study, we analyzed the proliferation and cytotoxic activities of LAK cells and initial phase TILs by stimulation with IL-4. IL-4 obviously inhibited the DNA synthesis of LAK cells and initial phase TILs at the concentration of 250 pg/ml and 25 pg/ml, respectively. Furthermore, IL-4 (25 ng/ml for LAK cells, 25 pg/ml for initial phase TILs) suppressed the cytotoxic activities against K562, KATO-III, and autologous tumor cells. The discrepancy of the concentration between the proliferation and the cytotoxicicity by IL-4 suggested different pathways in terms of the generation of LAK cells. In order to clarify the inhibitory mechanism of IL-4, we measured the expression of IL-2 receptor. IL-2 receptor alpha chain was strongly down-regulated by IL-4. Thus, IL-4 modulates the activation of LAK cells and initial phase TILs via the IL-2 receptor alpha chain.

Substance P induced by peripheral nerve injury in primary afferent sensory neurons and its effect on dorsal column nucleus neurons

Using in situ hybridization and the retrograde tracer, Fluorogold, we examined the expression of preprotachykinin (PPT) mRNA in the rat dorsal root ganglion neurons projecting to the gracile nucleus. Seven days after unilateral sciatic nerve transection, some medium- to large-sized neurons in the rat dorsal root ganglia projecting to the gracile nucleus express PPT mRNA, whereas very few gracile nucleus-projecting neurons on the contralateral side express PPT mRNA. Immunohistochemistry revealed an increase in substance P (SP) immunoreactivity in the gracile nucleus and large myelinated fibers in the dorsal root 2 weeks after unilateral sciatic nerve transection. The results suggest that medium to large DRG cells that project to the gracile nucleus express PPT mRNA de novo in response to peripheral nerve injury, and increased SP is transported to the gracile nucleus through large myelinated fibers. To determine whether the increased SP might affect the excitability of the gracile nucleus neurons postsynaptically, Fos expression after electrical stimulation of the injured sciatic nerve was examined. Multiple injections of the NK-1 receptor antagonist, CP-96,345, suppressed stimulus-induced Fos expression in gracile nucleus neurons including thalamic relay neurons. The inactive enantiomer, CP-96,344, had no effect on stimulus-induced Fos expression. These data indicate that the de novo synthesized SP in the lesioned primary afferent neurons may be involved in an augmentation of excitability in the dorsal column-medial lemniscus sensory pathway. This hyperexcitability may play a role in the pathogenesis of abnormal neuropathic sensations following peripheral nerve injury.

MR diagnosis of subacute and chronic subarachnoid hemorrhage: comparison with CT

OBJECTIVE

The purpose of our study was to compare the value of MR imaging with CT in the diagnosis of subarachnoid hemorrhage in the subacute and chronic stages (> 3 days after the hemorrhagic episode).

MATERIALS AND METHODS

We performed 42 MR examinations using a 0.5-T unit in 37 patients with subarachnoid hemorrhage caused by a ruptured aneurysm. Examinations were done 4-75 days after the ictus. We obtained 40 T1-weighted, 11 proton density-weighted, 15 T2-weighted, and 28 moderately T2-weighted images. CT was also performed in all patients within 24 hr of the MR examination. Confirmation of the presence of subarachnoid hemorrhage at the time of the MR examination was made by CSF examination using lumbar puncture or surgical findings.

RESULTS

In the subacute and chronic stages, subarachnoid hemorrhage was seen as an area of high signal intensity on T1-weighted, proton density-weighted, T2-weighted, and moderately T2-weighted MR images in 63%, 90%, 25%, and 92% of cases, respectively. On CT scans, subarachnoid hemorrhage was seen as an area of high attenuation in only 46% of cases. Especially in the chronic stage, subarachnoid hemorrhage was seen as an area of high signal intensity more frequently by MR imaging than by CT (90% on T1-weighted images; 100% on proton density-weighted images; 25% on T2-weighted images; 100% on moderately T2-weighted images; and 10% on CT scans). High-signal-intensity subarachnoid hemorrhage was demonstrated by MR imaging until a maximum of 39 days after the ictus, whereas high-attenuation subarachnoid hemorrhage was demonstrated by CT until a maximum of 17 days after the ictus.

CONCLUSIONS

Our findings show that MR imaging is superior to CT for the diagnosis of subacute and chronic subarachnoid hemorrhage. MR imaging is especially useful for the diagnosis of chronic subarachnoid hemorrhage.

A recessive mutant of the U937 cell line acquired resistance to anti-Fas and anti-p55 tumor necrosis factor receptor antibody-induced apoptosis

Human monocytic leukemia U937 cells readily undergo apoptosis when cells are treated with various stimuli including antitumor agents, tumor necrosis factor (TNF)-alpha and anti-Fas antibody. However, the signal transduction mechanism resulting in apoptosis is unclear. To study the mechanism of apoptosis, we isolated and characterized a mutant, UK110, from U937 cells, which was resistant to TNF-alpha and anti-Fas antibody-induced apoptosis but was less resistant to etoposide-induced apoptosis. TNF-alpha induced signals are mediated by two types of TNF receptors (TNFR), p55- and p75-TNFR, and p55-TNFR is homologous to the Fas antigen. Interestingly, UK110 cells showed resistance to apoptosis by agonistic anti-p55-TNFR antibody, indicating that UK110 cells were resistant to Fas- and p55-TNFR-mediated apoptosis. Because expression of apoptosis-associated molecules, such as c-Myc, Bcl-2, and Bax, was similar between U937 and UK110 cells an undetermined pathway for apoptosis through Fas and p55-TNFR could be mutated in UK110 cells. To clarify the genetic phenotype of UK110 cells, we performed somatic cell hybridization with parental U937 and the UK110 cells. All of the hybrid clones were as sensitive as the parental U937 cells to apoptosis by both anti-Fas and anti-p55-TNFR antibodies, indicating that the apoptosis resistance in UK110 cells resulted from recessive genotype.

Different localization of tau protein kinase I/glycogen synthase kinase-3 beta from glycogen synthase kinase-3 alpha in cerebellum mitochondria

We examined the subcellular distribution of two glycogen synthase kinase-3 (GSK-3) isoforms in rat cerebellum. Results from immunoelectron microscopy and subcellular fractionation revealed that one isoform, tau protein kinase I/GSK-3 beta (TPKI/GSK-3 beta), was present in mitochondria, but GSK-3 alpha was not. Although the two GSK-3 isoforms seem to have similar properties, the difference of subcellular localization observed here suggests that TPKI/GSK-3 beta fulfills some specific function in mitochondria.

Amyloid beta peptide induces cytoplasmic accumulation of amyloid protein precursor via tau protein kinase I/glycogen synthase kinase-3 beta in rat hippocampal neurons

Exogenous application of synthetic amyloid beta protein (A beta) is known to induce neurotoxic effects in rat hippocampal culture. We report here that A beta (25-35) induces accumulation of amyloid precursor protein (APP) derivatives in the cytoplasm of neurons. At the same time, the level of the secreted form of APP released into the culture medium decreases. Tau protein kinase I/glycogen synthase kinase-3 beta (TPK I/GSK-3 beta) antisense oligonucleotide blocked APP accumulation and prevented neuronal death. These results provide evidence that APP accumulation after A beta treatment is regulated by TPK I/GSK-3 beta. A beta neurotoxicity is probably mediated via phosphorylation of tau by TPK I/GSK-3 beta, resulting in an impairment of axonal transport, and cytoplasmic accumulation of APP.

Effects of extracellular matrices on tube formation of cultured rat hepatic sinusoidal endothelial cells

To determine the effects of extracellular matrices on the function and morphology of hepatic sinusoidal endothelial cells, isolated rat hepatic sinusoidal endothelial cells were cultured in three-dimensional fashion on collagen gel containing various extracellular matrix components. Cells cultured on type I collagen gel with or without type IV collagen formed a cobblestone appearance on the surface of the gel. Cells cultured on laminin-containing type I collagen gel invaded the gel and exhibited three-dimensional tube formation with a decreased number of characteristic endothelial pores. Morphometrically, there was a significant relationship between the length of the tube formed and the concentration of laminin in the type I collagen gel. Cells cultured on Matrigel, which contains high concentrations of laminin, type IV collagen, fibroblast growth factor, tissue plasminogen activator, and other growth factors, formed a great number of tubes into a network on the surface of the gel, as is observed in the situ hepatic sinusoidal endothelial cells. Ultrastructurally, tube-forming endothelial cells cultured on Matrigel had many endothelial pores on the cell surface, with tubes (approximately 10 microns in diameter) formed by two or three hepatic sinusoidal endothelial cells. These results indicated that extracellular matrix components, especially laminin, induced the formation of tubes in cultured rat hepatic sinusoidal endothelial cells. Tube-forming sinusoidal endothelial cells cultured on Matrigel could provide more advantages than the two-dimensional culture model for investigating the function and morphology of these cells in vitro.

Endothelin-1 contributes to antigen-induced airway hyperresponsiveness

Endothelin A (ETA)-receptors mediate ET-1 contractions of ovine airway smooth muscle. Therefore, the ETA-receptor antagonist, BQ-123, was used to test the hypothesis that ET-1 contributes to antigen-induced airway responses in sheep allergic to Ascaris suum. We first established the protective effect of BQ-123 by demonstrating that BQ-123 given as an aerosol (0.3 or 1.0 mg/kg in 3 ml buffer) or by continuous intravenous infusion (100 micrograms.kg-1.min-1) significantly blocked the bronchoconstriction to aerosolized ET-1 (0.2-200 micrograms/ml). To determine whether ET-1 contributed to antigen-induced airway responses, BQ-123 was given either as an intravenous infusion (100 micrograms.kg-1.min-1) beginning 30 min before and continuing for 8 h after antigen challenge or as an aerosol (1 mg/kg in 3 ml buffer) 30 min before and 4, 8, and 24 h after antigen challenge. Neither treatment with intravenous infusion nor aerosolized BQ-123 blocked the immediate antigen-induced bronchoconstriction, but both treatments significantly reduced the late response (approximately 50%). The treatments with aerosolized BQ-123 also blocked the antigen-induced airway hyperresponsiveness to inhaled carbachol seen 24 h after challenge. Subsequently, we found that sheep developed airway hyperresponsiveness to inhaled carbachol at 4 and 24 h after ET-1 challenge, an effect that was blocked by aerosolized BQ-123. We conclude that in allergic sheep 1) aerosolized ET-1 causes bronchoconstriction, in part, by stimulation of ETA-receptors, 2) ET-1 is released in the airways after antigen challenge, and 3) this peptide contributes to the severity of the allergic responses, probably by increasing airway smooth muscle responsiveness.

Acute subarachnoid hemorrhage: MR imaging with fluid-attenuated inversion recovery pulse sequences

PURPOSE

To evaluate the usefulness of fluid-attenuated inversion recovery (FLAIR) magnetic resonance (MR) imaging sequences in the detection of acute subarachnoid hemorrhage (SAH).

MATERIALS AND METHODS

MR imaging with FLAIR sequences was performed with a 0.5-T superconducting unit in 20 patients (aged 30-72 years) with acute SAH due to a ruptured aneurysm and in 27 control subjects (aged 32-72 years). FLAIR images were obtained 2 hours to 2 days after ictus. Findings were evaluated and compared with computed tomographic (CT) findings.

RESULTS

In all patients, acute SAH was clearly demonstrated as an area with signal intensity that was high relative to that of the normal cerebrospinal fluid and surrounding brain parenchyma at FLAIR imaging. This sequence was especially useful in demonstration of acute SAH in the posterior fossa, which was difficult to show at CT because of beam-hardening artifacts. In a double-blind comparison, no FLAIR images acquired in control subjects were confused with those acquired in control subjects were confused with those acquired in patients.

CONCLUSION

FLAIR sequences reliably provide diagnostic images in patients with acute SAH.

Retinoic acid induces gene expression of fibroblast growth factor-9 during induction of neuronal differentiation of mouse embryonal carcinoma P19 cells

We have found that the gene expression of the ninth member of the fibroblast growth factor (FGF) family, FGF9 was induced during retinoic acid(RA)-induced neuronal differentiation of murine embryonal carcinoma P19 cells. We have reported here the nucleotide sequence of the mouse FGF9 cDNA. The murine cDNA showed 92.4% nucleotide sequence homology to the human FGF9 cDNA and 98.2% homology to that of rats. This mouse FGF9 cDNA encoded a polypeptide consisting of 208 amino acids with amino acid sequence identical to that of rats. Only one amino acid was replaced compared to the human homolog. The highly conserved sequence homology of FGF9 suggests its functional importance. FGF9 was originally isolated from a culture medium of a human glioma cell line as a growth-promoting factor for glial cells [5]. Upon induction of neuronal differentiation by forming cell aggregates with 10(-6) M RA, the gene expression of FGF9 was increased biphasically during the first 96 hours when cells were aggregating and from 168 hours to 192 hours followed by plating onto a tissue culture dish as glia-like cells proliferated. Neither undifferentiated P19 cells nor the cells aggregated without RA remaining undifferentiated expressed FGF9. This indicates that RA regulates the gene expression of FGF9 that may play an important role in neuronal differentiation in both early and late developmental process.

Survey of Pseudomonas aeruginosa contamination in human beings and laboratory animals

Several serotypes of Pseudomonas (P.) aeruginosa were isolated from the oral cavities of researchers, but no positive cases were found among the animals they had contacted or in the environment. These results indicated that researchers are not a source of P. aeruginosa infection for animals. However, P. aeruginosa was detected on the hands of researchers and animal caretakers after they finished their work. The same serotype of P. aeruginosa was found in the animals and the environment. These findings demonstrated that the researchers and the animal caretakers were contaminated with P. aeruginosa by the animals, and then became infective vehicles.

Transport and metabolism of glutathione isopropyl ester in cerebrospinal fluid

The transport of glutathione (GSH) or glutathione isopropyl ester (GSH isopropyl ester) to the cerebrospinal fluid (CSF) in rats was estimated by levels of GSH or GSH isopropyl ester and their metabolites in CSF 30 min after the intravenous administration of GSH or GSH isopropyl ester (300 mg/kg). Although the CSF uptake of GSH isopropyl ester was almost equal to that of GSH as evidenced by about a two-fold increase in the amount of non-protein sulfhydryl groups in CSF, the sum of GSH isopropyl ester and GSH concentrations in the CSF after GSH isopropyl ester treatment was increased by 32% compared with saline-treated controls. On the other hand, treatment with GSH had no significant increase in GSH levels in CSF but increased its metabolite levels, such as cysteinyl-glycine and cysteine. GSH isopropyl ester was less metabolized than GSH. GSH isopropyl ester had low affinity to purified gamma-glutamyl transpeptidase, a key enzyme for metabolism of GSH in the choroid plexus, supporting the finding that GSH isopropyl ester is more stable than GSH in CSF. These results are compatible with our previous report (Yamamoto et al. (1993) showing that the protective action of GSH isopropyl ester against cerebral ischemia was greater than that of GSH in rats. GSH isopropyl ester may be a useful agent which protects the brain from the damage associated with oxygen-related toxicities by increasing GSH levels in the CSF.

256 × 256 Turnover-type free-space multichannel optical switch based on polarization control using liquid-crystal spatial light modulators

Free-space multichannel optical switches using polarization control are attracting interest for future telecommunication networks and interconnection networks in computers. We describe a switching architecture, the turnover type, for such free-space multichannel optical switches. The architecture makes it possible to realize a large-scale and transparent optical switch that is also compact. A 256 × 256 multichannel optical switch based on the architecture is designed and fabricated. To the authors' knowledge, the channel number of the fabricated switch is the largest yet reported among rearrangeable optical switches. Switching operation and signal transmission at 400 Mbits/s are performed successfully with a prototype switch.

Role of cytoskeleton and acidification of endocytic compartment in asialoglycoprotein metabolism in isolated rat hepatocyte couplets

The process of receptor-mediated endocytosis is common to a variety of species and cell types. One of the best characterized receptor-ligand systems is the hepatocyte receptor for asialoglycoproteins. We investigated the morphological features of the uptake and intracellular transport of gold-conjugated asialofetuin in isolated rat hepatocyte couplets. We assessed the effects of colchicine, lumicolchicine, cytochalasin B, and chloroquine on the uptake and intracellular transport of asialoglycoproteins. Isolated rat hepatocyte couplets were incubated with gold-conjugated asialofetuin, and transmission electron micrographs of these cells were analyzed to determine the density and distribution of gold particles in the peripheral and pericanalicular areas. Results were analyzed morphometrically. Colchicine significantly inhibited the uptake and intracellular transport of asialoglycoproteins, but did not affect membrane fusion of endocytic compartments in the peripheral area. Lumicolchicine and cytochalasin B had minimal effects on these processes. Chloroquine inhibited the uptake of asialoglycoproteins, but did not affect the intracellular transport of asialoglycoproteins. Results suggest that the microtubule is essential for intracellular movement of endocytosed asialoglycoproteins and receptor recycling, and that endocytic structures in the peripheral regions can fuse in the absence of intact microtubules. We also found that uptake and intracellular transport of asialoglycoproteins were independent of the microfilaments, and the pH gradient in endocytic compartments was important in receptor-mediated endocytosis of asialoglycoproteins.

Non-T cell disturbance causes the suppression of the autologous mixed lymphocyte reaction in patients with gastric carcinoma

We investigated the accessory function of non-T cells to autoreactive T cells in autologous mixed lymphocyte reaction (AMLR) and clarified the cause of the suppression of autoreactivity in patients with gastric carcinoma. The response of T cells in the AMLR in gastric cancer patients was significantly suppressed compared with that in controls. In patients in whom the AMLR of the spleen was suppressed more than that of the peripheral blood, the degree of stimulation of non-T cells from the spleen was remarkably suppressed, on the other hand, in patients in whom AMLR of the peripheral blood was suppressed more than the spleen, the degree of stimulation from the peripheral blood was remarkably suppressed. The expression of HLA-DR antigens on non-T cells of gastric cancer patients was lower than that of controls. AMLR was considerably decreased in controls by the treatment non-T cells with anti-HLA-DR MoAb, but not in cancer patients. Treatment of non-T cells from the spleen of gastric cancer patients with IFN-gamma remarkably improved T cell proliferation in the AMLR. IFN-gamma also enhanced the expression of HLA-DR antigens on non-T cells. The disturbance of non-T cells was not biased to a specific population. These disturbances of non-T cells suppressed the AMLR independently of stage status. Therefore, the immunological abnormality of non-T cells manifested by reduced accessory function to autoreactive T cells may cause impaired immunological surveillance against tumors and permit cancer cell growth.

Coexpression of trk family members and low-affinity neurotrophin receptors in rat dorsal root ganglion neurons

We examined the colocalization of trk family and low-affinity neurotrophin receptor (LANR) mRNAs by means of in situ hybridization histochemistry in rat dorsal root ganglion (DRG) neurons. About 35-40%, 5%, and 15-20% of DRG neurons were positive for trkA, trkB, and trkC mRNAs, respectively. Each member of the trk family was coexpressed with LANR. The trkB mRNA-expressing neurons essentially lacked trkA and trkC mRNAs, and most of trkA and trkC mRNAs-expressing neurons (85-90%) belonged to different subpopulations, suggesting that they are involved in different functions.

[Clinical analysis on 40 cases of primary aldosteronism--long-term follow-up of blood pressure]

Forty cases of primary aldosteronism after adrenalectomy were observed from 1975 to 1993 at Yokohama City University hospital. All of them had adrenocortical adenoma producing aldosterone. These cases are evaluated retrospectively on localization, surgical approach and long term follow up blood pressure. These patients were from 26 to 65 years old (average 46.6), and consisted of 11 males and 29 females. Fourteen adenomas were located on the right adrenal gland, 25 on left, and one case had adenomas on bilateral adrenal glands. On localization study, 39 cases had been correctly diagnosed by combined diagnostic method of selective adrenal venous sampling, selective adrenal venography, adrenal scintigraphy, X-ray CT, and MRI, with each diagnostic values being 65.8%, 69.0%, 72.5%, 96.9%, 100% respectively. This analysis suggests that, in almost cases, it is enough to diagnose the laterality by adrenal scintigraphy, X-ray CT and MRI. Selective venous catheterization is not always necessary to know the laterality of the tumor. For surgical approach to the adrenal gland, 16 adenomas were removed through anterior subcostal incision (transabdominal approach) from 1975 to 1988, and 24 cases through lumbar oblique incision or dorsal incision (extra peritoneal approach) from 1986 to 1993. This analysis reveals that lumbar oblique and dorsal incision provided us superior surgical approach to the adrenal gland. Thirty-eight cases had been followed after adrenalectomy for more than one year (average 57.6 months). Blood pressure had been normalized in 28 cases, but 10 cases had remained hypertensive.(ABSTRACT TRUNCATED AT 250 WORDS)