Cell biology of somatolactin

Somatolactin (SL) is a novel pituitary protein, isolated for the first time from the Atlantic cod. The corresponding proteins have been identified in several toleost species, but not in other classes of vertebrates. Comparison of amino acid sequence has revealed SL molecules to be related to growth hormone (GH) and prolactin (PRL) in teleosts and other vertebrates, suggesting that SL is a new member of the GH/PRL family. Unlike GH and PRL, SL can exist in either glycosylated or nonglycosylated form, depending on the species; most teleosts possess glycosylated SLs, except for salmonids whose SLs are simple proteins. The SL-producing cells are located in the pars intermedia bordering the neurohypophysis and are distinct from melanocyte-stimulating hormone (MSH)-producing cells. The SL cells are PAS positive in most teleosts but chromophobic in salmonids, which may reflect the glycosylation status of SL. Its biochemical and molecular features have become increasingly clear, whereas its physiological significance is still poorly understood. Several possible roles for SL have been suggested, including roles in maturation, calcium regulation, stress response, acid-base regulation, fat metabolism, and background adaptation. Although direct evidence is lacking for any of the proposed functions, this involvement in acid-base regulation appears most probable, since other proposed biological events linked to SL should more or less affect the acid-base status in fish. More detailed studies are needed to define the function of SL.

Crystal-storing histiocytosis associated with lymphoplasmacytic lymphoma mimicking Weber-Christian disease: immunohistochemical, ultrastructural, and gene-rearrangement studies

A case of crystal-storing histiocytosis associated with lymphoplasmacytic lymphoma is presented. Unlike previous cases, this patient presented with signs and symptoms suggestive of Weber-Christian disease. Biopsy of subcutaneous nodules showed numerous deposits of crystal-storing histiocytes with lymphoplasmacytic cells, the latter exhibiting light chain restriction (lambda-chain) with a predominance of immunoglobulin (Ig)G heavy chain. Polymerase chain reaction (PCR) analysis of CDR-II* region of the immunoglobulin heavy chain locus confirmed monoclonality of the lymphoplasmacytic cells in the nodule. Electron microscopy showed polygonal-shaped amorphous crystals, characteristic of immunoglobulin in the histiocytic cells. Crystal-storing histiocytosis should be examined by immunohistochemical and DNA analysis to confirm or exclude the possibility of lymphoplasmacytic lymphoma.

Cytotoxicity of phosphatidylcholine hydroperoxides is exerted through decomposition of fatty acid hydroperoxide moiety

The cytotoxicity of phosphatidylcholine hydroperoxides synthesized regioselectively and stereoselectively was examined in human umbilical vein endothelial cells. Phosphatidylcholine hydroperoxides were readily incorporated into cells, after which the contents declined gradually. Phosphatidylcholine with an arachidonic acid hydroperoxide residue was toxic to cells, while phosphatidylcholine with a linoleic acid hydroperoxide residue had no effect. The toxicity of phosphatidylcholine with arachidonic acid hydroperoxide disappeared after the reduction of the hydroperoxide by triphenylphosphine. Phosphatidylcholine with arachidonic acid hydroperoxide that had decomposed partially upon standing at room temperature was much more toxic than the pure hydroperoxide. 4-Hydroxynonenal, known widely as a toxic secondary product in the lipid peroxidation of polyunsaturated fatty acids, was detected in the decomposition mixture of phosphatidylcholine hydroperoxide. Phosphatidylcholine hydroperoxide incorporated into cells did not show toxicity when the hydroperoxide-containing medium was changed to growth medium after a short time. On the other hand, the phosphatidylcholine hydroperoxide was toxic in cells treated with the lipophilic free radical generator, 2,2'-azobis(2,4-dimethylvaleronitrile). In addition, cells were damaged by long-term treatment in medium containing phosphatidylcholine hydroperoxide and its decomposition products. These results suggest that the toxicity of phosphatidylcholine hydroperoxides is exerted by toxic compounds arising from the decomposition of the hydroperoxide moiety.

Computer survey for likely genes in the one megabase contiguous genomic sequence data of Synechocystis sp. strain PCC6803

Using the computer program GeneMark, the open reading frames (ORFs) previously assigned within the one megabase sequence data of the genome of the cyanobacterium, Synechocystis sp. strain PCC6803 (Kaneko et al., DNA Res. 2: 153-166, 1995), were re-examined. Matrices required by GeneMark for its statistical calculation were generated and modified by running a script termed GeneMark-Genesis that performed recursive application of GeneMark against the Synechocystis data and evaluated the probability scores for optimization. Based on the matrices thus generated, 752 of the 818 previously assigned ORFs (92%) were supported by GeneMark as likely coding sequences, of which 26 were predicted to start at more internal positions than previously assigned. In addition, 50 ORFs were newly identified as likely coding sequences, most of them being shorter than 300 bp. Thus, the procedure was proven to be very powerful to locate likely coding regions within the genomic sequence data of Synechocystis without having prior information concerning their similarity to the genes of other organisms. However, GeneMark did not predict 66 previously assigned ORFs as likely genes: 14 of them showed significant degrees of similarity to known genes and 10 others were found within IS-like elements. It seems that these genes, many of which appear to be exogenous origin, escaped detection by GeneMark as in the case of "class 3 (horizontally transferred) genes" of E. coli, which in turn suggests that genes of different phylogenetic origins might also be detected as such by modifying the matrices.

Effect of a novel histamine H2 receptor antagonist, IT-066, on acute gastric injury induced by ischemia-reperfusion in rats, and its antioxidative properties

The effect of a novel histamine H2 receptor antagonist IT-066 (3-amino-4-[4-[4-(1-piperidinomethyl)-2-pyridyloxy]-cis-2-++ +butenylamino]- 3-cyclobutene-1,2-dione hydrochloride), on acute gastric mucosal injury induced by ischemia-reperfusion was investigated from the standpoint of oxygen radical-mediated lipid peroxidation in rats. Ischemia-reperfusion injury was produced in the rat stomach by applying a small vascular clamp to the celiac artery for 30 min and subsequent removal of the clamp for 60 min. The decrease in gastric mucosal blood flow was not influenced by treatment with IT-066. The antiulcer activity of IT-066 was demonstrated in this injury after intragastric ingestion as well as after intravenous injection. IT-066 significantly inhibited this injury in the presence of exogenous HCl. The mucosal protection by IT-066 was not reversed by pretreatment with indomethacin or nitric oxide synthase inhibitor. The increase in lipid peroxides in the gastric mucosa after ischemia-reperfusion was significantly inhibited by the intragastric treatment with IT-066 at doses of 1.0 and 3.0 mg/kg. The total area of erosions closely paralleled the accumulation of lipid peroxide with a significant correlation. A spin trapping method using 5,5-dimethyl-1-pyrroline-N-oxide showed that IT-066 scavenged superoxide radical and hydroxyl radical generated by the hypoxanthine-xanthine oxidase system and the hydrogen peroxide-ferrous iron system, respectively. IT-066 also significantly inhibited the in vitro increase of lipid peroxide in the gastric mucosal homogenates induced by a free radical initiator. These results suggest that the protective effect of IT-066 against ischemia/reperfusion-induced gastric mucosal injury may result in part from its antioxidative properties.

Intraportal endovascular ultrasonography in the diagnosis of portal vein invasion by pancreatobiliary carcinoma

OBJECTIVE

The purpose of this study was to determine the value of intraportal endovascular ultrasonography (IPEUS) in the diagnosis of portal vein invasion by pancreatobiliary carcinoma. The authors reported their experiences with this new technique and compared it with conventional imaging technologies, such as portography and computed tomography (CT).

SUMMARY BACKGROUND DATA

Pancreatobiliary carcinoma often invades the portal vein. Observation of the echogenic band of the portal vein wall by means of a high-frequency, high-resolution intravascular ultrasound catheter allows for the accurate diagnosis of the portal vein invasion.

METHODS

A prospective study of 30 consecutive patients with pancreatobiliary carcinoma (16 pancreatic carcinomas, 8 bile duct carcinomas and 6 gallbladder carcinomas) was performed. In 23 cases IPEUS was performed intraoperatively from the superior mesenteric venous route with an 8 French, 20 MHz intravascular ultrasound catheter. In 7 cases IPEUS was performed before surgery from the percutaneous transhepatic route with a 6 French, 20 MHz intravascular ultrasound catheter. The finding of IPEUS was confirmed by pathologic examination of resected specimens and surgical exploration. The results of IPEUS were compared to those of portography and CT.

RESULTS

Intraportal endovascular ultrasonography visualized the portal vein wall as an echogenic band with a thickness of 0.5 mm to 1.0 mm. The diagnostic criterion of portal vein invasion was destruction of this echogenic band. Portal vein invasion was found in 15 of 30 cases. Vascular invasion was confirmed by pathologic examination of resected specimens in 10 patients and operative findings in 5. The sensitivity, specificity, and overall accuracy of IPEUS for diagnosis of portal vein invasion was 100%, 93.3%, and 96.7%, respectively. The values were 80%, 67.7%, and 73.3% for portography and 53.3%, 80%, and 66.7%, respectively, for CT.

CONCLUSIONS

Intraportal endovascular ultrasonography provided precise information about the relationship between the pancreatobiliary tumor and the portal vein wall. It was capable of accurately detecting or excluding early invasion of the portal vein wall by pancreatobiliary carcinoma.

Intracaval ultrasonography in the diagnosis of tumour involvement of the vena cava

A retrospective study of 34 consecutive patients with possible tumour involvement of the vena cava was performed to assess the usefulness of intracaval ultrasonography. Twenty-five of the 34 patients were operated and resection carried out in 23, including seven with combined resection of the vena cava. The sonographic criterion for vena cava invasion was obliteration of the echogenic ring of the vena cava wall or intracaval tumour mass. The sensitivity, specificity and overall accuracy of intracaval endovascular ultrasonography in the diagnosis of tumour involvement of the vena cava were 100, 96 and 97 per cent respectively. The respective values were 91, 61 and 71 per cent for computed tomography and 82, 67 and 72 per cent for cavography. Ultrasonography is a useful technique that can precisely evaluate the vena cava for possible tumour invasion, especially when the presence or extent of tumour involvement is not definitely established by conventional imaging techniques.

Glutaminase-positive and glutaminase-negative pyramidal cells in layer VI of the primary motor and somatosensory cortices: a combined analysis by intracellular staining and immunocytochemistry in the rat

Pyramidal neurons in layer VI of the primary motor and somatosensory cortices were examined by a combined method of intracellular recording, biocytin injection, and immunocytochemistry using in vitro slice preparations of rat brain immunofluorescence staining revealed that biocytin-injected pyramidal cells in layer VI were separated into glutaminase (PAG)-immunopositive and PAG-immunonegative cells. Although the two groups of pyramidal cells showed no statistically significant differences in passive membrane properties and spike characteristics, a clear difference was found in spike afterpotentials. Ten of 12 PAG-positive pyramidal cells showed no or a small fast afterhyperpolarization (fAHP), whereas 10 of 11 PAG-negative pyramidal cells displayed a large fAHP. Depolarizing afterpotentials were observed only in PAG-positive pyramidal cells than in PAG-negative cells. In contrast, the arborization of basal dendrites was more developed in PAG-positive pyramidal cells than in PAG-negative cells. The main axons of all the pyramidal cells entered the subcortical axons of all the pyramidal cells entered the subcortical white matter. The local axon collaterals of PAG-positive pyramidal cells were widely spread in the horizontal direction, whereas those of PAG-negative cells were distributed vertically along the dendritic tree. Since PAG is considered to be a marker of glutamatergic neurons in the cerebral cortex, the present results indicate that layer VI pyramidal cells are separated into glutamatergic and nonglutamatergic neurons that have different electrical properties and input-output organizations. Thus, cortical outputs from layer VI are suggested to use at least two distinct systems.

[A case of one stage-repair of interrupted aortic arch and ventricular septal defect in neonate using a separated cardiopulmonary bypass]

We report a case of one stage-repair of interrupted aortic arch and ventricular septal defect in neonate. The operation was performed at the age of 14 days. After a median sternotomy incision, a separated cardiopulmonary bypass was commenced through the ductus and a 4 mm EPTFE graft which was anastomoted to the right subclavian artery. Cerebral circulation was maintained through the graft during reconstruction of the aortic arch. Our method is useful regarding that brain damage can be avoided which may be induced by total circulatory arrest.

HLA B44-restricted cytotoxic T lymphocyte responses to the peptides of HCV nucleoprotein residues 81-100 in patients with chronic hepatitis C

Human leukocyte antigen B44-restricted cytotoxic T lymphocytes (CTLs) recognize an epitope in hepatitis C virus (HCV) nucleoprotein residues 81-100. CTLs that recognize two wild-type peptides 81-100 of HCV genotypes 1b/II and 2a/III were generated from peripheral blood lymphocytes of each of three patients studied. Although CTLs that recognize a wild-type peptide 81-100 of HCV genotypes 1a/I and 2b/IV were not generated from any patient, CTLs that recognize peptide 81-100 of a rare HCV isolate of type 1a/I were generated from two patients. The results suggest that HLA B44-restricted CTLs recognize most, if not all, HCV isolates of types 1b/II and 2a/III and rare variants of type 1a/I and that the wild-type HCV isolates of genotypes 1a/I and 2b/IV may be less immunogenic for HLA B44-restricted CTLs.

A minimal and optimal cytotoxic T cell epitope within hepatitis C virus nucleoprotein

Amino acid residues 81-100 of the hepatitis C virus (HCV) nucleoprotein contain a cytotoxic T cell epitope that is recognized by cytotoxic T lymphocytes (CTLs) in association with human leukocyte antigen B44. With panels of truncated and overlapping peptides, the minimal and optimal epitope recognized by CTLs was shown to be a 9-mer peptide (residues 88-96). The peptide can stimulate effectively CTLs that are able to recognize endogenously synthesized and processed HCV nucleoprotein.

A macromolecular multicomponent peptide vaccine prepared using the glutaraldehyde conjugation method with strong immunogenicity for HIV-1

The immunogenicity of a newly constructed macromolecular multicomponent peptide vaccine candidate against human immunodeficiency virus type 1 (HIV-1) was compared with that of previously reported vaccine candidates. This vaccine candidate is composed of a macromolecular multicomponent peptide complex consisting of three V3 region peptides, one Gag region peptide, and CD4-binding site peptide and was constructed using the multiple-antigen peptide and glutaraldehyde methods. Sera from rabbits immunized with this newly constructed vaccine showed strong antibody titers against each constituent peptide antigen. Furthermore, these antibodies exhibited strong neutralizing and antifusion activity toward HIV-1IIB, HIV-1MN, and fresh isolates from Japanese HIV-seropositive individuals. These results show that this new vaccine candidate has the capacity to induce strong, polyvalent immunogenicity and therefore may prove to be a powerful peptide vaccine against HIV-1 infection.

Apoptosis in tumors and normal tissues induced by whole body hyperthermia in rats

Apoptosis in tumor and normal tissues was examined in rats treated with whole-body hyperthermia (WBH; 41.5 degrees C for 2 h). WBH alone produced 0.5 day of tumor growth delay (TGD) in a fibrosarcoma and 5.8 days of TGD in the Ward colon carcinoma. This difference in WBH-induced TGD indicates that the fibrosarcoma is relatively resistant to WBH, whereas the Ward colon carcinoma is relatively heat sensitive. A quantitative histological assay for apoptosis demonstrated that the extent of apoptosis in the fibrosarcoma reached a maximum level of 19% 4 h after WBH and returned to the control level by 24 h. In contrast, WBH induced apoptosis with a peak value of 43% at 8 h in the Ward colon carcinoma, and the apoptotic level remained elevated above the control level until 48 h after WBH. Within normal tissues, the spleen and the lymph nodes showed WBH-induced apoptosis; however, the highest level of WBH-induced apoptosis as well as the most prolonged increase in apoptotic levels occurred in the thymus. The WBH-induced apoptosis in the thymus remained elevated above the control level until 48 h after WBH. Within the entire gastrointestinal tract, the small intestine was the most sensitive to WBH. Apoptotic cells were observed in the small bowel mucosa following WBH exposure. We also noted a minor WBH-induced increase in the apoptotic level in the bone marrow. Except for the case of the thymus, increased apoptotic levels in the normal tissues declined after peak levels at 4 h, and apoptosis above control levels was not seen beyond 12 h following WBH. Thus, within the normal tissues, WBH-induced apoptosis declined to basal levels within 12-48 h. These data indicate that both the extent and the kinetics of WBH-induced apoptosis differ between the two tumors and, meaningfully, between tumor and normal tissues. The extent and duration of apoptosis seem to correlate with tumor response to WBH.

Sequence variations of the pancreatic islet/liver glucose transporter (GLUT2) gene in Japanese subjects with noninsulin dependent diabetes mellitus

To assess the genetic susceptibility to noninsulin-dependent diabetes mellitus (NIDDM) in Japanese subjects, we investigated the role of GLUT2 gene defects in patients with NIDDM. When the allelic frequency of a simple tandem repeat polymorphism in the GLUT2 gene was compared, the allele with 155 base pairs was more common in NIDDM patients (n = 99) than in controls (n = 89; 5.1% vs. 0.6%; P = 0.0118, by Fisher's exact test), whereas this was not significant after the correction for multiple comparisons. To directly identify mutations, we then analyzed each of 11 exons by the polymerase chain reaction-single strand conformation polymorphism analysis in 60 NIDDM patients. We found 2 missense mutations in exon 3: CCC-->CTC (Pro68-->Leu) in 1 patient and ACT-->ATT (Thr110-->Ile) in 3 patients, all in the heterozygous state. These mutations were not found in 60 control subjects. To evaluate the significance of the Pro68-->Leu mutation, the family members of the proband were studied. The mutation did not appear to be associated with the disease or other clinical parameters including change in immunoreactive insulin/change in plasma glucose or oral glucose load. The other mutation (Thr110-->Ile) is known to be functionally insignificant. We identified 4 additional nucleotide changes, all of which appeared to be silent. We concluded that the mutations in the GLUT2 gene were not major determinants of genetic susceptibility to NIDDM in Japanese.

[Pulmonary tuberculosis with systemic lymph node swelling]

A 31-year-old woman was admitted to our hospital because of cervical and axillar lymph node swelling. A chest X-ray film showed many nodular shadows and a cavity in the left upper lung field. The tuberculin test was positive. Transbronchial lung biopsy and cervical lymph node biopsy were done. Examination of the biopsy specimens revealed epithelial granulomas with caseous necrosis. Thus, pulmonary tuberculosis with systemic lymph node swelling was diagnosed. Examinations during the patient's hospital stay showed that she was not an immunocompromised host. Pulmonary tuberculosis with systemic lymph node swelling occurs only rarely in a non-immunocompromised host.

Reduced attention-related negative potentials in methamphetamine psychosis

Auditory event-related potentials were recorded during a dichotic syllable discrimination task in 16 unmedicated patients who were in the residual state following the remission of acute methamphetamine (MAP) psychosis, and in 16 age-matched normal controls. The subjects were instructed to press a button in response to the target syllables applied to one designated ear. In the patients with MAP psychosis, the area of attention-related negative potentials was significantly smaller than that in the normal controls. The two groups did not differ significantly in P300 amplitude or latency. These results suggest that patients with MAP psychosis show impairment of selective attention, although they have less cognitive deficit than schizophrenic patients.

Role of recruited neutrophils in interleukin-8 production in dog trachea after stimulation with Pseudomonas in vivo

Cell-free supernatant of Pseudomonas aeruginosa (PA) recruits neutrophils into the airways indirectly by inducing the production of chemotactic factors, including interleukin-8 (IL-8). PA products stimulate IL-8 expression selectively in surface airway epithelium, gland ducts, serous cells, and recruited neutrophils. To examine the relative contribution of neutrophils in IL-8 release in the airway lumen, we studied the effect of inhibition of neutrophil recruitment on IL-8 concentration in tracheal fluid after introduction of PA supernatant into the dog trachea in vivo. Tracheal superfusion with PA supernatant caused neutrophil recruitment and increased the IL-8 concentration in the tracheal lumen; NPC 15669 inhibited both effects. To study whether migration of neutrophils into the airway lumen per se induces their expression of IL-8, we compared effects of local introduction of IL-8 and of PA supernatant into the trachea on IL-8 expression in neutrophils recruited into the trachea. PA supernatant, but not exogenous IL-8 alone, induced IL-8 mRNA expression in neutrophils recruited into the trachea. To determine what product(s) of PA stimulate IL-8 expression in neutrophils, we examined neutrophils isolated from peripheral blood. PA supernatant induced IL-8 production in neutrophils, an effect reproduced by PA lipopolysaccharide and inhibited by polymyxin B. These results suggest that neutrophils recruited into the airway lumen play a major role in local IL-8 production in airways in response to bacteria such as PA, depending on the presence of stimuli such as lipopolysaccharide.

Dose- and route-dependent alteration of metabolism and toxicity of chloroform in fed and fasting rats

Effects of overnight food deprivation on the metabolism and toxicity of chloroform (CHCl3) administered to rats per os (po), intraperitoneally (ip), or by inhalation (inh) at different doses were investigated. Rats that had been either deprived of food overnight or normally fed were challenged with CHCl3 either po (0, 100, 200, or 400 mg/kg), ip (0, 100, 200, or 400 mg/kg), or inh (0, 50, 100, or 500 ppm for 6 hr). Overnight fasting increased CHCl3 metabolism in vitro about threefold with a decrease of liver glutathione content to 67%. The fasting caused route- and dose-dependent alteration in the metabolism and toxicity of CHCl3. The area-under-the-curve (AUC) of blood CHCl3 concentration was invariably smaller following po than ip administration, and CHCl3 administered po caused more severe hepatic damage than did the same amount of CHCl3 administered ip. With po administration, the AUC (toxicity) of CHCl3 in fasting rats was significantly smaller (higher) than that of fed rats at a dose as small as 100 mg/kg, whereas, with ip administration at such a small dose, fasting caused no significant alteration in the AUC (toxicity). When rats were exposed by inhalation to CHCl3 vapor, food deprivation had little or no effect on either the blood concentration or the toxicity until the exposure concentration was raised to 500 ppm. The present study indicates that po administration is different from both ip and inh administration with regard to the effect of enzyme induction on the toxicokinetics of CHCl3, mainly due to the first-pass metabolism unique to po administration.

Presynaptic localization of mu-opioid receptor-like immunoreactivity in retinal axon terminals within the terminal nuclei of the accessory optic tract: a light and electron microscope study in the rat

Neuropil within the terminal nuclei of the accessory optic tract of the rat showed intense to moderate mu-opioid receptor-like immunoreactivity (MOR-LI). After unilateral enucleation, MOR-LI within the terminal nuclei almost disappeared or was markedly reduced on the side contralateral to the operation. Electron microscopy revealed that MOR-LI axon terminals within the terminal nuclei were filled with round synaptic vesicles and in asymmetric synaptic contact mainly with dendritic profiles, and occasionally with somatic profiles.

[Leukoencephalopathy in a patient being treated for small cell lung cancer]

A 62-year-old man was given a diagnosis of small cell lung cancer, and received 6 courses of combination chemotherapy (PE therapy) composed of cisplatin (80 mg/m2, day 1) and etoposide (100 mg/m2, days 1, 2, 3). Multiple brain metastases were found, and whole brain irradiation (44 Gy) was given. Eleven months after radiotherapy, he suffered from dizziness and abnormal gait. Enhanced CT of the head showed slight enlargement of the lateral ventricles and markedly low density of the white matter, but no evidence of intracranial tumor involvement. A magnetic resonance scan (axial T2-weighted) showed symmetric extensive hyperintensity in the white matter. Treatment-related leukoencephalopathy caused by the PE therapy and whole brain irradiation was diagnosed. He was alive 8 months after the appearance of neurological symptoms, without recurrence of lung cancer. A search of the literature revealed no previous report of leukoencephalopathy related to PE therapy.

[Anomalous origin of the right pulmonary artery from the ascending aorta: a case report]

We report a successful case of anomalous origin of the right pulmonary artery from the ascending aorta. A 34 days old infant, who had suffered from cardiogenic shock, underwent a direct anastomosis of the right pulmonary artery to the main pulmonary artery behind the ascending aorta under cardiopulmonary bypass. Postoperative catheterization showed no significant stenosis over the anastomosis and normalized pulmonary artery pressure. We conclude that early surgical correction is necessary in the treatment of this life threatening disease.

Nasal natural killer (NK) cell lymphoma: report of a case with activated NK cells containing Epstein-Barr virus and expressing CD21 antigen, and comparative studies of their phenotype and cytotoxicity with normal NK cells

Malignant lymphomas arising from the nasal cavity have been considered to be derived from T cells, but recent surface marker studies suggest that more than half of the lymphomas are derived from natural killer (NK) cells. Here we describe a case of nasal lymphoma whose lymphoma cells were identified as NK cells by morphological, phenotypic, immunogenotypic, and functional studies. We believe this is the first study with functional evidence of NK activity. When compared with normal freshly isolated NK cells or activated NK cells, the surface phenotypes and NK activity of the patient tumour cells were those of the activated, but not resting, NK cells. Also, Epstein-Barr virus (EBV) was detected in the tumour cells and the lymphoma cells were found to be monoclonally expanded. The patient's lymphoma cells also expressed EBV receptor CD21 (CR2) and CD30 (Ki-1) that have not been described on normal NK cells. We therefore examined highly enriched NK cells of normal donors, and found that some resting and/or activated NK cells express these antigens.

The new oral hypoglycemic agent, CS-045, inhibits the lipid peroxidation of human plasma low density lipoprotein in vitro

Several lines of evidence have revealed that the oxidative modification of low-density lipoprotein (LDL) is probably associated with the genesis of the atherosclerotic region. CS-045 is a new (thiazolidine) class of oral hypoglycemic agent which has a hindered phenol in the side chain (an analogue of alpha-tocopherol). The present results indicate that CS-045 had a relatively high antioxidative potency in inhibiting the lipid peroxidation of human plasma LDL in vitro induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) compared with that of alpha-tocopherol. These findings suggest that CS-045 may be useful in preventing the progression of atherosclerosis in diabetic patients.

Co-localization of mu-opioid receptor-like and substance P-like immunoreactivities in axon terminals within the superficial layers of the medullary and spinal dorsal horns of the rat

The presence of mu-opioid receptor-like immunoreactivity (MOR-LI) on axon terminals was confirmed by light and electron microscopy within the superficial layers of the medullary and spinal dorsal horns of the rat. By means of double-immunofluorescence histochemistry, co-localization of MOR-LI and substance P (SP)-LI was occasionally observed in axon terminals within the superficial layers of the dorsal horns.