[Role of serotonin in impaired gas exchange during pulmonary embolism]

Although serotonin has been reported to play a substantial role in cardiopulmonary dysfunction, the quantitative effects of serotonin, released from activated platelets, on the development of alveolar flooding and on impaired gas exchange in pulmonary embolism have not been systematically investigated. To elucidate the effects of serotonin on pulmonary hemodynamics, accumulation of edema fluid in alveolar space, and impairment of gas exchange in acute pulmonary embolism, 20 mongrel dogs were given 0.4-0.6 g/kg of glass beads with a diameter of 100 microns, via the internal jugular vein. Before and after embolization, pulmonary hemodynamics, systemic hemodynamics, blood gases, and the distribution of ventilation-perfusion ratios (VA/Q) in the lung were measured, with and without a newly developed selective antagonist of the serotonin S2 receptor, DV-7028. VA/Q distribution was determined by applying the multiple inert gas elimination technique. After glass-bead embolization, the animals that did not receive DV-7028 showed significant increases in pulmonary arterial pressure and in extravascular lung water, widened alveolar-arterial O2 tension differences, and appreciable development of low VA/Q areas (0 < VA/Q < or = 0.1). These changes were prevented in the animals that received DV-7028. However, DV-7028 did not affect the formation of high VA/Q areas (VA/Q > 10). In conclusion, in acute canine pulmonary embolism serotonin not only induces pulmonary hypertension and pulmonary edema, but also worsens gas exchange through the formation of low VA/Q areas.

[Investigation of discrepancy between 99mTc-HMPAO and 133Xe rCBF SPECT; a comparative study with X-ray CT findings]

To investigate the discrepancy between 99mTc-hexamethylpropyleneamine oxime (HMPAO) and 133Xe rCBF SPECT, the findings of thirty patients with reasonable rCBF reduction on 133Xe SPECT were compared with HMPAO SPECT and X-ray CT. The subjects did not include the cases of acute and subacute CVD. Both SPECT were performed within two weeks by ring-type dynamic SPECT (HEADTOME, Simadzu, Japan). In comparison between the SPECT findings by 133Xe and 99mTc-HMPAO, the subjects were classified into three groups as follow. Group A: Similar findings in the both SPECT were noted in 6 cases (20%). Group B: Smaller findings on HMPAO SPECT than that by 133Xe were in 11 cases (37%). Group C: No findings of rCBF reduction on HMPAO SPECT were in 13 cases (43%). The rCBF of the lesion measured by 133Xe SPECT in the group C was 24-35 ml/100 g/min. The density of HMPAO in the lesion did not correlate with the rCBF value. Only the severity of CT findings tend to correlate with the density of HMPAO. These results suggest that the reduction of HMPAO density depends directly on some kind of neural injury rather than the rCBF value. The injury may be caused by the flow reduction under the threshold of each neural cell. So the correlation between HMPAO density and actual rCBF might show like sigmoid curve. Then the HMPAO SPECT might directly reflect the regional extraction and fixation ratio, and the reduction of blood flow cause the minute neural-injury in the lesion of moderately reduced rCBF.

[Immunochemiluminometric assay (Automated Chemiluminescence System ACS: 180) for CEA]

We examined Automated Chemiluminescence System ACS: 180 for CEA assay, especially about confidence of the functional sensitivity. Serum CEA levels of normal subjects and patients were measured not only with ACS: 180 but also with immunoradiometric assay (CEA kit [Daiichi] II). Using ACS: 180 assay for CEA, intra-assay coefficients of variation (C.V.s) were 4.06% at 1.97 ng/ml, 1.62% at 17.3 ng/ml, and 2.28% at 81.3 ng/ml. Interassay C.V.s were 4.02% at 1.99 ng/ml, 1.21% at 16.5 ng/ml, and 3.44% at 79.4 ng/ml. The detection limit (functional sensitivity) of ACS: 180 assay for CEA was 0.4 ng/ml by the precision profile. The coefficient of correlation of 164 sera, which CEA values were among 0.4-100 ng/ml (working range of ACS: 180), between with ACS: 180 and with CEA kit [Daiichi] II was R = 0.942, y = 1.07 x +0.09 (p < 0.05). Seven (13.2%) normal subjects (n = 53) and 45 (34.1%) patients with malignant diseases (n = 132) had higher serum CEA levels than the cut off value (2.5 ng/ml). The sera of 82 malignant patients who had both pre- and post-operation sample were determined. Sixty-five patients of them were decrease after operation. These results of ACS: 180 resembled to that of CEA kit [Daiichi] II. We conclude that ACS: 180 for CEA assay was precise enough to measure below the cut off value, and had good performance of its speed (short incubation) and convenience.

Role of exotoxin A in inducing severe Pseudomonas aeruginosa infections in mice

The effects of exotoxin A (EXA) from Pseudomonas aeruginosa on polymorphonuclear leucocytes (PMNLs) were studied in a mouse model and in vitro. P. aeruginosa PA103, which produced EXA, was 20 times more virulent for normal mice than was its EXA-deficient mutant, PA103-29. EXA was detected in the plasma of mice infected with P. aeruginosa PA103, and its presence correlated with increasing numbers of bacteria in the blood and internal organs. A monoclonal antibody (MAb) against EXA prevented the death of the mice if it was given simultaneously with, or 2 h before, infection with strain PA103. The number of PMNLs in murine blood decreased by 50% within 30 min of intravenous injection of EXA, but this decrease was prevented by simultaneous or prior injection of MAb to the toxin. EXA inhibited in-vitro phagocytosis and killing of P. aeruginosa by human and murine PMNLs and decreased the number of the PMNLs by between 60 and 68%. Collectively, these results not only confirm that EXA is toxic in vivo, but also suggest that this toxin accelerates the growth of virulent P. aeruginosa in mice.

Stable human T-lymphotropic virus type I carrier rates for 7 years among a teenaged blood donor cohort of 1986 in Kumamoto, Japan

The human T-lymphotropic virus type I (HTLV-I) carrier rates for blood donors in Kumamoto, Kyushu, Japan for 8 years, 1986-1993, are currently available. The data show that 16-19-year-olds in 1986 and 20-29-year-olds in 1993 represent nearly the same cohort, because the median age in both groups is 24.5 years in 1993. Therefore, comparison of the HTLV-I positive rate for the two groups gives an estimate of the change in the rate over 7 years within the cohort. In males, 265 of 22,143 donors (1.20%) were seropositive for HTLV-I among 16-19-year-olds in 1986, and 214 were seropositive among 20,076 (1.07%) donors in 20-29-year-olds in 1993. In females, 203 were seropositive among 20,677 (0.98%) donors in 16-19-year-olds in 1986, and there 154 were seropositive among 18,660 (0.83%) donors in 20-29-year-olds in 1993. Thus, the seropositive rates declined in both sexes. However, the average annual rate of immigration to Kumamoto Prefecture was 2.37%. If seropositive rates for 20-29-year-olds in 1993 are adjusted for the dilution effect due to immigration (under the assumption that all immigrants were HTLV-I negative), the adjusted carrier rate for males is 1.26% and that for females is 0.98%. The adjusted carrier rates for both sexes are almost the same as those for 16-19-year-olds in 1986. This indicates that horizontal transmission was negligible for those in the cohort who were in their early reproductive period. Using all 8 year carrier rates for 16-19-year-olds and 20-29-year-olds, chronological changes of 20-29-year-olds, in the near future was estimated. The best goodness of fit model indicated that the HTLV-I carrier rate will decline exponentially, and that the rate will decrease by 50% approximately every 10 years for both sexes. It is probable that in recent years south-west Japan has lost the conditions that are favorable for HTLV-I endemicity and the virus will be virtually non-endemic within a few generations.

Mycobacterium avium-intracellulare pleuritis with massive pleural effusion

Atypical mycobacterial infection is seldom accompanied by pleural involvement. We report a very rare case of Mycobacterium avium-intracellulare pleuritis with massive pleural effusion. The patient was a non-immunocompromised 35-year-old Japanese male with insidious onset of fever, chest pain and anorexia. The pleural effusion gradually resolved with empirical antimycobacterial treatment, leaving considerable pleural adhesion and thickening.

[A case of large cell carcinoma of the lung arising from the inner surface of a pulmonary bulla and complicated by hematoma]

A 64-year-old man with a history of smoking was admitted to our hospital, because he was noted to have a solitary mass lesion at the apex of the right lung on a chest roentgenogram. Eight months before admission, he had come to our hospital because of hemoptysis. At that time, however, no abnormal shadow was seen on his chest roentgemogram, except for multiple bullae at both apexes. Based on chest CT findings on admission, the tumor appeared to be a hematoma growing inside the bulla. The resected tumor was found to contain a large amount of coagulated blood in the bulla. Histopathological examination of the bulla revealed a proliferation of large atypical cells from the inner surface of the bulla toward the inner space. Thus, the diagnosis was large cell carcinoma within the wall of the pulmonary bulla, the inside of which was filled with hematoma. We believe that the hematoma in the bulla allowed us to make an early diagnosis, and thus to succeed in curing the patient.

Fibrolipomatous hamartoma of the lung: a case report and review of the literature

A fibrolipomatous hamartoma of the lung in a 57-year-old Japanese man is reported. Computed tomography revealed an abnormal mass with fatty and soft tissue densities in the upper portion of the right lung, indicating a liposarcoma. Upon resection, the tumor was found to consist of a 7.5 x 4.0 cm soft, yellowish mass continuous with a 3.0 x 1.5 cm polyp. The tumor was composed primarily of mature fibro-adipose tissue with some glandular and cartilaginous components, which identified it as a fibrolipomatous hamartoma. Follow-up studies of the patient for two years after surgery found no sign of malignancy. Thus, lipomatous or fibrolipomatous hamartoma should be considered as a possible diagnosis whenever atypical lipomatous lung tumors are encountered.

Temperature-sensitive mutation of DNA polymerase alpha induces growth-suppressive phenotypes involving retinoblastoma protein and cyclin D1

Temperature-sensitive (ts) cell cycle mutant mouse cell, tsFT20, is deficient in DNA polymerase alpha activity to initiate DNA replication at replicon origins. Here, we analyzed phenotypes concerning growth control genes in the arrested tsFT20 cells. Analysis of cyclins showed that expression levels of cyclin D1, which is essential for G1/S transition, remarkably decreased in the mutant cells after temperature up-shift. Further we examined phosphorylation states of retinoblastoma protein (pRB) in the cells. Though the tsFT20 cells arrested in G1/S-S phase at nonpermissive temperature (Eki et al., (1990) J. Biol. Chem. 265 26-33), a large proportion of pRB was found as an underphosphorylated growth-suppressive form in the arrested cells. In revertant cell lines of tsFT20, pRB was not underphosphorylated even at nonpermissive temperature. The pRB underphosphorylation occurred later than the decrease of mRNA levels of cyclin D1, thus the underphosphorylation may be caused by the decrease in amount of cyclin D1 protein. These results indicated that the mutational inactivation of DNA polymerase alpha evokes phenotypes in which the inhibitory machinery of G1/S transition has been turned on.

A protective role for lymphocytes in cyclophosphamide-induced endogenous bacteraemia in mice

Cyclophosphamide (CY) is used in many animal studies, including models of bacteraemia, to deplete peripheral neutrophils and induce a compromised state. Although CY also influences lymphocyte function, the protective role of lymphocytes in bacteraemia is unclear. Therefore, CY (200 mg/kg) was administered to ddY mice and its influence on the number, cellular composition, and function of lymphocytes in the spleen and Peyer's patches was examined. A single dose of CY reduced the number of lymphocytes in a time-dependent fashion. Flow cytometry showed that B cells carrying B220 antigen decreased significantly. The production of IgA in Peyer's patches, as measured by enzyme-linked immunosorbent assay, was also suppressed in a time-dependent fashion. Blastogenic responses of splenic lymphocytes to Concanavalin-A, lipopolysaccharide and heat-killed Pseudomonas aeruginosa were suppressed 48 h after CY administration. The results suggest that CY suppresses the number and function of lymphocytes, especially B cells. This may lead to bacterial overgrowth in the gut and result in bacteraemia. Intravenous transfusion of normal lymphocytes or oral inoculation of IgA to mice with P. aeruginosa D4 endogenous bacteraemia significantly increased survival rates, indicating that lymphocytes and their products have a protective role in bacteraemia in mice.

Nucleotide sequence and replication properties of the Bacillus borstelensis cryptic plasmid pHT926

The nucleotide sequence of pHT926, a cryptic plasmid found in Bacillus borstelensis HP926, was determined. pHT926 replicates by a rolling-circle mechanism and belongs to the pC194 plasmid family. The copy number of pHT926 was fourfold higher than that of pUB110 and very stably maintained in Bacillus choshinensis.

Frequent expression of genes for receptor tyrosine kinases and their ligands in human pancreatic cancer cells

Limited information is available concerning the involvement of growth factor receptors and their ligands in the pathogenesis of human pancreatic cancer. We analyzed 12 human pancreatic cancer cell lines by Northern blot analysis for the expression of 9 receptor tyrosine kinase (RTKs) and 6 growth factors. The effect of a monoclonal antibody (MAb) against transforming growth factor-alpha (TGF-alpha) on in vitro pancreatic cancer cell growth was also assessed, mRNA for EGF-R, c-erbB-2 and c-erbB-3 was expressed in 12 (100%), 12 (100%), and 7 (58%), respectively, of the cell lines examined. In addition, 8 (67%) cell lines expressed the c-met/receptor for hepatocyte growth factor. As for ligands, TGF-alpha mRNA was detected in 10 (83%) cell lines; MAb against TGF-alpha inhibited growth of the 2 cell lines examined. Furthermore, mRNA for amphiregulin (AR) was expressed in 10 (83%) cell lines. Coexpression of TGF-alpha, AR, and EGF-R was observed in 9 (75%) cell lines. These results support the concept that several specified types of RTKs and their ligands are closely involved in regulation of the growth of human pancreatic cancer cells.

[Clinical analysis of the complex repetitive discharge following M wave]

In the nerve conduction study (NCS), the complex repetitive discharge (CRD) which follows M wave is occasionally observed. To understand the origin of CRD, we clinically analyzed the cases with CRD. Among the 1,580 cases examined by NCS, 13 (0.82%) cases including 6 of myotonic dystrophies (MyD), 2 of carpal tunnel syndrome and a case of multiple sclerosis, chronic inflammatory demyelinating polyradiculoneuropathy, compression fracture of a lumbar vertebra, myasthenia gravis (MG) or Isaacs' syndrome had CRD. CRD was divided into forms; one consisted of an attenuating train of the complex of muscle potentials (muscular form) and the other one formed a simple repetition of single motor unit action potential (neural form). MyD, MG, and Isaacs' syndrome showed muscular form, and the others neural form. The pathophysiology of CRD was considered from the sites of lesions of nerve terminals, neuromuscular junctions, or muscle fibers and that the neural form might result from the axonal regeneration of peripheral motor nerve fibers.

Purification and characterization of recombinant hamster tissue complement C1s

Hamster complement C1s cDNA was inserted into expression plasmid BCMGSNeo, and transfected to SEA7 cells, A31 mouse fibroblasts transformed by polyoma virus. The transfectant secreted a large amount of recombinant C1s that was activated in the serum free culture medium and hydrolyzed acetyl-Gly-L-Lys-naphthyl ester (AGLNE). C1s was purified to a homogeneity from the culture medium of the transfectant by DEAE-Sephadex, Dymatrex orange A and size-exclusion HPLC. Purified hamster C1s consumed human complement in hemolytic assay and hydrolyzed gelatin in enzymography. To investigate the enzymic action of C1s at molecular levels, several antibodies were prepared against hamster C1s. One peptide (amino-acid residues 379-391) and two peptides (amino-acid residues 478-496 and 560-583) corresponding to the heavy and the light chain, respectively, were synthesized. The amino-acid sequences of these regions is not conserved between hamster and human C1s. Antibodies against these peptides were raised in rabbits. The anti-peptide antibodies bound specifically to hamster serum and recombinant C1s but not to human C1s. They inhibited the esterase activity of recombinant C1s to varying degrees depending on each antibody's binding site.

Magnetic resonance tomographic angiography: diagnostic value in trigeminal neuralgia

A combination of MRI, MR angiography and MR tomographic angiography (MRTA) was used to study the relationship of the root exit zone of the trigeminal nerve to surrounding vascular structures in seven patients with trigeminal neuralgia (TN) and ten patients with no evidence at a lesion in this region. MRTA is the technique for showing the relationship between vessels, cranial nerves and brain stem. MRTA clearly demonstrated the presence of a vessel at the root exit zone of the trigeminal nerve in all patients with TN. In the ten other patients, examination of 20 trigeminal nerves revealed that only one nerve (5%) was in contact with a vessel at the root exit zone. This study supports vascular compression of trigeminal nerves as a cause of TN, and demonstrates the value of MRTA as noninvasive technique for demonstrating compression.

Enzyme-linked immunosorbent assay of pro-gastrin-releasing peptide for small cell lung cancer patients in comparison with neuron-specific enolase measurement

Our previous study demonstrated that pro-gastrin-releasing peptide(31-98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients.

Methylmalonic acidemia: brain lesions in a case of vitamin B12 non-responsive (mut0) type

Neuropathological findings were described in a 9-day-old female infant who died of the vitamin B12 non-responsive (mut0) type of methylmalonic acidemia (MMA). Widespread karyorhectic fragments of varying size and shape were noted throughout the brain, in particular densely accumulated in the cerebellar granular layers and the layer IV of the striate cortex. Bilateral or symmetrical necrotic foci were observed in various regions of the grey matter: Sommer's sector of the hippocampus, basal ganglia, thalamus, hypothalamus and brainstem. In the cerebral cortex small spongy necrotic foci were scattered mainly in the depths of gyri. Alzheimer type II astrocytes appeared in the preserved zone of the caudate nucleus. Myelinated nerve fibers in the brainstem were spongy or vacuolated, whereas peripheral myelin sheaths of cranial nerves were intact. Multiple hemorrhagic foci were noted in the cerebellum, predominantly the granular layers. The lymphoid tissue in the spleen and the thymus was hypoplastic. It may be difficult to explain exactly the mechanisms of the pathological changes observed here on routine light microscopy; the outcome of systemic ischemia/hypoxia before death cannot be completely ignored. But, it is suggested that widespread karyorhexis may occur selectively in specific cells (or cell groups), including immature neurons and other cellular components (glial and/or mesenchymal cells) among the patients with the mut0 type of MMA.

Three-dimensional-MRI of neurovascular compression in patients with hemifacial spasm

We prospectively studied 30 patients to assess the usefulness of three-dimensional (3D) contrast-enhanced MRI in patients with hemifacial spasm. In all patients neurovascular compression of the facial nerve could be detected. Microvascular decompression was performed in 14, and vascular compression of the root exit zone of the facial nerve and the offending artery were exactly as predicted by MRI in all but 2. We also retrospectively studied whether the symptomatic side could be defined only by enhanced 3D MRI in 55 randomised individuals (30 with and 25 without hemifacial spasm). All symptomatic sides were correctly identified, and the false-positive rate was 13.8%.

Brain tissue identification based on myosin heavy chain isoforms

Non-muscle tissues contain 3 myosin heavy chain (MHC) isoforms; MIIA, MIIB1 and MIIB2. MIIA is a non-muscle type isoform distributed in all non-muscle tissues and smooth-muscle, while MIIB1 and MIIB2 are brain-type isoforms distributed mainly in neuronal tissues. The ratio of MIIA and MIIB (A/B ratio) differs between tissues, suggesting that this ratio may be a useful marker for tissue identification. To apply the A/B ratio for tissue identification in forensic practice, we developed a highly sensitive ELISA for quantification of each MHC isoform. At least 100 pg of both MHC isoforms could be detected by the present method. Analysis of the A/B ratio of the cerebrum, cerebellum, liver, kidney, spleen and andrenal gland by the present method indicated that the A/B ratio of the brain tissue (< 0.5) was quite different from other tissues (> 3.0). The A/B ratio could be determined from at least 8 micrograms of fresh tissue sample and 0.1 mg of dried tissue sample stored for 1 month at room temperature. Therefore, the A/B ratio seems to be an excellent marker for identification of the brain tissue.

[Surgery of aneurysm of the left subclavian artery applying imaged thoracoscopy--a case report]

A 23-year-old male with aneurysm of the left subclabian artery was successfully treated by means of imaged thoracoscopic surgery. The operation was carried out using double-lumen endotracheal anesthesia. Short trocars were inserted through the left intercostal spaces to introduce a flexible video thoracoscope and surgical instruments. After the area around the proximal end of the subclabian artery was exposed, a tape and Nelaton tube were applied in order to interrupt the artery completely. The maneuvors for aneurysm could be accomplished with minimum invasion, and without thoracotomy. The advantages of this thoracoscopic surgery are: less postoperative pain and discomfort, early recovery and short hospital stay, and cosmetic preservation.

The complete amino acid sequence of lectin-C from the roots of pokeweed (Phytolacca americana)

The complete amino acid sequence of pokeweed lectin-C (PL-C) consisting of 126 residues has been determined. PL-C is an acidic simple protein with molecular mass of 13,747 Da and consists of three cysteine-rich domains with 51-63% homology. PL-C shows homology to chitin-binding proteins such as wheat germ agglutinin, and all eight cysteine residues in the three domains of PL-C are completely conserved in all other chitin-binding domains.

High degree of myeloid differentiation and granulocytosis is associated with t(8;21) smoldering leukemia

The t(8;21) is a frequent chromosome abnormality in acute myeloid leukemia (AML), particularly associated with M2 of the French-American-British (FAB) classification, but also found in a few patients with myelodysplastic syndrome (MDS). The two genes involved in the t(8;21) have been recently isolated and the cDNA of the AML1/ETO fusion gene identified. We have investigated a series of AML and MDS patients by a reverse transcriptase-polymerase chain reaction (RT-PCR) and analyzed the clinical and laboratory features of leukemia with t(8;21). The t(8;21) was only found in a subset of M2, which had the clinical and hematological features distinct from those M2 without t(8;21). M2 with t(8;21) was associated with a significantly higher myeloid differentiation and with a good response to chemotherapy. Moreover, among the patients with refractory anemia with excess of blasts in transformation (RAEB-T) the t(8;21) was also significantly associated with a higher myeloid differentiation and a good response to chemotherapy. M2 patients with t(8;21) could be distinguished on a number of hematological parameters, eg white blood cell count and percentage of bone marrow myeloblasts and promyelocytes, from RAEB-T carrying the t(8;21). Based on these findings we suggest that leukemia patients carrying t(8;21) can be grouped into two types; overt acute myeloid leukemia (M2) and smoldering or slowly evolving myeloid leukemia.