Assignment of imino proton signals of G-C base pairs and magnesium ion binding: an NMR study of bovine mitochondrial tRNA(SerGCU) lacking the entire D arm

The mammalian mitochondrial tRNA(SerGCU) (mt tRNA[SerGCU]) has a unique structure in that it lacks the whole D arm. To elucidate its higher-order structure, we synthesized unmodified bovine mt tRNA(SerGCU) using T7 RNA polymerase and measured its 1H-NMR spectrum in the imino proton region. Although the imino proton signals heavily overlapped, we succeeded in assigning all the seven imino proton signals of the G-C base pairs by a combination of base replacement and 15N-labeling of the G residues of a whole tRNA molecule or of the 3'-half fragment. The results indicate that the tRNA possesses the secondary structure that has been supposed on the basis of biochemical studies. Analysis of the effect of the magnesium concentration on the G-C pairs suggests that the acceptor and T stems do not form a co-axial helix, and that the core region of the tRNA does not interact with magnesium ions. These features are significantly different from those of canonical tRNAs. Despite this, it is very likely that the tRNA as a whole takes a nearly L-shape tertiary structure.

Detection of the Circulating Lung Cancer Marker Lcap with a New Monoclonal Antibody Trd-L1

Lung Cancer Associated Protein (LCAP) is a high molecular weight glycoprotein defined by the monoclonal antibody (MAb) DF-L1 prepared against a primary adenocarcinoma of the lung. Previous studies have demonstrated that LCAP circulates at elevated levels in patients with lung cancer. However, a suitable assay for monitoring LCAP levels has not been available. The present work describes the development of a double-determinant LCAP assay using MAb TRD-L1 as the capture antibody and MAb DF-L1 as the tracer. In 60 normal subjects, the mean LCAP level was 4.8 U/ml with 2 (3.3%) subjects having values >12 U/ml (mean + 2SDS). By contrast, 37 of 67 (55.2%) patients with lung cancer had LCAP levels >12 U/ml. Moreover, only 14 of 203 (6.9%) patients with benign lung disease had elevated levels. LCAP levels were most commonly elevated (62.7%) in patients with adenocarcinoma of the lung and with advanced disease. These results indicate that LCAP as detected by MAb TRD-L1 is a potentially useful marker for the evaluation of patients with lung cancer.

Arterialized occipitoparietal osteocutaneous flap

We treated a case of postoperative osteomyelitis and epidural abscess in the left temporal and parietal region. The scalp and skull defect following debridement was reconstructed immediately with an arterialized occipitoparietal osteocutaneous flap that was supplied proximally by the occipital artery and distally by the superficial temporal artery. This method is one of the alternative methods for small to moderately sized skull and scalp defects in the temporal, parietal, and occipital areas without available superficial temporal artery.

[Phase II study of combination chemotherapy with cisplatin, carboplatin and etoposide (CPVP) in unresectable non-small cell lung cancer: analysis of survival time and prognostic factors]

Phase II study of combination chemotherapy with cisplatin, carboplatin and etoposide (CPVP) was conducted in 46 patients with unresectable non-small cell lung cancer. In the previous paper, we showed that CPVP produced a satisfactory response rate without major toxicities. In the present paper, survival time and prognostic factors were analyzed. The median survival time (MST), 1- and 2-year survival of 46 patients (III A4, III B15, IV 27) were 14.1 months, 57.0% and 18.2%, respectively. In prognostic analysis, responders survived significantly longer than non-responders (MST: 15.8 vs 11.0 months, p < 0.05). Large cell carcinoma and stage IV have proven to be indicators of poor prognosis. Females and patients less than 60 years old tended to do better. With regard to the relationship between the time from initiation of treatment to response and survival time, late responders (response after 3 or 4 courses) survived significantly (p < 0.05) longer than early responders (response after 1 or 2 courses). The CPVP regimen is not only practical, but also very effective. It deserves further study to reveal its advantages compared to the other platinum compound containing regimens.

Renal angiotensin-converting enzyme localization in diabetic rats and the effect of low protein diet

Recent evidence suggests a role of angiotensin-converting enzyme (ACE) in diabetic nephropathy. The effect of diabetes and low protein diet on renal immunohistochemical ACE localization was studied in streptozotocin-induced DM rats. Immunohistochemical ACE localization was reduced in DM rats, and a low protein diet partially resolved this abnormality while inhibiting the progression of diabetic nephropathy.

Renal hemodynamic changes induced by captopril and angiotensin-converting enzyme gene polymorphism

We studied the relationship between renal hemodynamic changes induced by a single acute administration of captopril (50 mg p.o.) and angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism in 27 healthy human volunteers, 7 with DD genotype, 10 with ID, and 10 with II genotype. The increase in effective renal plasma flow (p < 0.02) and the fall in renal vascular resistance (p < 0.01) in response to captopril were significantly less in subjects with the DD genotype than in subjects with the other genotypes. These data suggest that intrarenal ACE inhibition by captopril differs according to ACE gene ID polymorphism in healthy humans.

Phase II study of irinotecan and etoposide in patients with metastatic non-small-cell lung cancer

PURPOSE

To determine the effects of irinotecan (CPT-11) given in combination with etoposide (VP-16) in metastatic non-small-cell lung cancer (NSCLC), to evaluate response and survival rates, and to determine the qualitative and quantitative toxicities of the combination chemotherapy.

PATIENTS AND METHODS

Sixty-one metastatic NSCLC patients received concurrent administration of CPT-11 and VP-16 for 3 days with recombinant human granulocyte colony-stimulating factor (rhG-CSF) support.

RESULTS

Fifty-nine patients were assessable for response and all 61 patients were assessable for toxicity and survival. Fifty-six patients were treated with two or more courses of chemotherapy. Thirteen patients achieved a partial response (PR), 36 showed no change (NC), and 10 showed progressive disease (PD). The overall response rate was 21.3% (95% confidence interval, 12.9% to 33.1%). The median duration of PRs was 141 days (range, 62 to 299). Of the hematologic toxicities, 14 (23%) and 24 (39%) patients experienced grade 3 or 4 leukopenia and neutropenia, respectively. The toxicities were feasible. Treatment-related death occurred in one patient who suffered hypovolemic shock induced by hematemesis. The median survival time was 10.0 months and the 1-year survival rate was 36.1%.

CONCLUSION

Combination chemotherapy with concurrent administration of CPT-11 and VP-16 with rhG-CSF support was only modestly effective against metastatic NSCLC, with feasible toxicities of moderate diarrhea and pulmonary toxicity. The results were equivalent to those expected with either cisplatin-based chemotherapy or with CPT-11 alone.

Phase I/II study of combination chemotherapy with cisplatin, carboplatin and etoposide in small cell lung cancer

A Phase I/II study of combination chemotherapy with cisplatin (CDDP), carboplatin (CBDCA) and etoposide (VP-16) (CPVP) was conducted in patients with small cell lung cancer. The dose level of etoposide was fixed at 100 mg/m2, while the doses of CDDP and CBDCA administered at each of the four steps were 50/200, 60/200, 60/250 and 70/250 mg/m2, respectively. Nine patients were allocated to each step dose group. Adverse effects were evaluated during the first two courses to establish the maximum tolerated dose (MTD). As a result, the step 3 doses turned out to be the MTD. The dose-limiting factor was hematotoxicity. Gastrointestinal toxicity was also present, but was tolerated. The overall response rate in patients with measurable or evaluable lesions was 91%. In 22 chemotherapy-naive patients, the median survival time was 16.6 months. These results suggest that the recommended dose is step 2, and that the CPVP regimen might be both more tolerable and more effective than the standard PVP regimen. Based on the above findings, CPVP therapy warrants further study in Phase II and III trials.

Alpha-fetoprotein-producing adenocarcinoma of the lung

We herein present a case of metachronous primary lung cancers, the first of which was adenosquamous cell carcinoma and the second of which was poorly differentiated adenocarcinoma. At the time the second lung cancer was detected 5 years after being operated on for the first cancer, a high level of serum alpha-fetoprotein (AFP) was noticed, but no elevation of other tumor markers was observed. In addition, no liver metastases, chronic liver diseases or other systemic abnormalities were seen either. The serum AFP level was 696 ng/ml, and the profile of lectin affinity showed a tumor-derived pattern. Two weeks after the operation, the serum AFP level decreased to a normal level. An immunohistochemical analysis confirmed that the exact origin of AFP was the tumor tissue. A specimen taken from the first lung cancer was not stained by the same procedures, which thus indicated this case to be a double primary lung cancer.

[The clinical value of BMIPP on the evaluation of myocardial ischemia and metabolism before and after CABG]

To evaluate the clinical usefulness of BMIPP (15-(p-[125I]-iodophenyl)-3-R, S-methylpentadecanoic acid), BMIPP and T1 imaging were underwent before and after surgery in 25 CABG patients. Preoperatively the demonstrated lesion on BMIPP scintigram is almost the same as that on rest-T1 scintigram. A month after CABG, the recovery on T1 scintigram was remarkable, however improvement on BMIPP was limited. These results suggest that on the evaluation of myocardial ischemia, the clinical value of BMIPP is almost the same as that of rest-T1 before CABG. The postoperative discrepancy between T1 and BMIPP scintigram suggests that the restoration of myocardial circulation does not directly improve myocardial metabolism.

Alterations of p16/CDKN2, p53 and ras genes in oral squamous cell carcinomas and premalignant lesions

Exons 1-3 of the p16/CDKN2 gene, exons 4-9 of the p53 gene and exons 1 and 2 of H-, K- and N-ras genes were screened for mutations by a combination of immunohistochemistry and single-strand conformational polymorphism (SSCP) analyses of polymerase chain reaction products from human surgical samples of both frank oral squamous cell carcinomas and premalignant lesions. The samples included 20 squamous cell carcinomas, 10 epithelial dysplasias and 10 epithelial hyperplasias. No identifiable gene mutations were detected in any of the dysplasias or hyperplasias, while 2 (10%) deletions and 2 (10%) mutations of p16/CDKN2, along with 5 (25%) p53 mutations were found in the advanced carcinomas, yielding characteristic p16/ CDKN2 and p53 changes. A mutation in the K-ras gene was found in single carcinoma and dysplastic samples. From the data, it can be argued that p16/CDKN2 and p53 mutations are relatively late occurrences in human oral tumorigenesis and that genetic alterations of the ras genes may not play a significant role in squamous neoplasia.

[A case report of concomitant carotid and coronary artery reconstruction]

We reported a case of a 70-year-old female who underwent simultaneous carotid endarterectomy and coronary artery bypass surgery. Preoperatively, cardiac catheterization demonstrated three vessel coronary artery disease. Her carotid angiogram revealed a 90% stenosis in the left common carotid artery. The cerebral blood flow scintigram on acetazolamide stress detected severely reduced cerebral blood flow on her left anterior and temporal lobe. Her postoperative course was uneventful. Postoperatively, no reduced cerebral blood flow was detected on the acetazolamide stress image. In patients with significant carotid artery stenosis, the cerearal blood flow scintigraphy on acetazolamide stress was a useful method for the simultaneous carotid endarterectomy and coronary artery bypass surgery.

Evaluation of gamma camera-based measurement of individual kidney function using iodine-123 orthoiodohippurate

Gamma camera-based clearance techniques which use the renal uptake ratio (RUR) of the radiotracer are available to estimate the effective renal plasma flow (ERPF) and glomerular filtration rate. To evaluate the accuracy of these techniques, we measured RUR by an optimized procedure and compared it with standard ERPF. Iodine-123 orthoiodohippurate (OIH) scintigraphy and simultaneous para-aminohippurate clearance study for measuring standard ERPF were performed in three hospitals in 24 patients with normal or mildly impaired renal function. 123I-OIH was injected intravenously and 10-s consecutive imaging of the kidneys was started when the abdominal aorta was seen. The attenuation coefficient for 123I was measured in each hospital using the same water-equivalent absorption materials and used for the attenuation correction. After subtracting background radioactivity, RURs were defined as the count ratios of fractional renal uptakes based on the integral from 1 to 2, 2 to 3, 1.5 to 2.5 and 1 to 3 min after the injection of 123I-OIH in relation to injected doses using the following three procedures in respect of attenuation correction: (1) RUR without attenuation correction, (2) RUR with fractional renal uptake corrected by the measured attenuation coefficient, (3) RUR with the total injected dose corrected by the absorption material. To decide upon the appropriate correction method and time interval, RURs were compared with standard ERPF. Among the three correction methods, procedure 2 showed the highest correlation between RUR and standard ERPF, but the correlation coefficient was low (r=0.75). No significant difference was observed among the RURs of each time interval. Individual kidney function measured from early renal uptake may be inaccurate even when appropriate correction is made for attenuation, background activity or time lag between injection and data acquisition. Gamma camera-based measurement of renal function using 123I-OIH is limited with regard to accuracy and reproducibility, though it is convenient and non-invasive.

Intratumor cellular heterogeneity and alterations in ras oncogene and p53 tumor suppressor gene in human prostate carcinoma

To assess the potential role of ras oncogene activation and p53 tumor suppressor gene mutations in the development of human prostate carcinoma, nine cases of histologically heterogeneous prostate tumors obtained from total prostatectomies were probed for these specific events. Each tumor was divided into 5 to 10 areas according to different growth or histological patterns. Targeted DNA sequences coding for ras and p53 were amplified by the polymerase chain reaction, analyzed by single-strand conformational polymorphisms, and confirmed by direct DNA sequencing. Point mutations of the ras gene were found in three of the nine tumors. Two contained K-ras codon 13 and H-ras codon 61 mutations, found in only one and three areas of each lesion, respectively. The third tumor contained two different point mutations in K-ras codons 13 and 61 in different foci of the sample. Loss of heterozygosity at the polymorphic codon 72 in the p53 gene was detected in two of four informative cases (50%) showing fragment cleavage by restriction fragment length polymorphism analysis. Mutations in p53, missense transversions, single base insertions, and two base deletions were also detected in three tumors. The present results reveal mutated ras and p53 occasionally occurring in small foci of the tumor and that genetic mutations in p53, as opposed to those in ras, are more closely associated with invasive growth of heterogeneous prostate carcinoma.

Effect of methimazole on rat renal carcinogenesis induced by N-ethyl-N-hydroxyethylnitrosamine

The effect of methimazole on N-ethyl-N-hydroxyethylnitrosamine (EHEN)-induced renal lesions was investigated in a medium-term initiation/promotion bioassay in male Wistar rats. EHEN-initiated rats underwent unilateral nephrectomy of the left kidney and subsequent addition of the renal tumor promoters trisodium nitrilotriacetate (NTA), potassium dibasic phosphate (PDP), or hydroquinone (HQ), alone or in combination with methimazole, to the diet for 20 wk. The addition of methimazole reduced the severity of simple and adenomatous renal hyperplasias induced by NTA, PDP, and HQ, but had no effect on the number of renal cell tumors that arose in EHEN+NTA groups. Methimazole also decreased the bromodeoxyuridine (BrdU) labeling indices, but had little effect on the expression of alpha 2u-globulin in treated kidneys as compared to controls. It appears that methimazole exhibits antagonistic properties to nongenotoxic nephrotoxins, protecting against renal damage but not against tumorigenesis, probably arising from genotoxic insult.

[The clinical value of MIBG myocardial spect before and after CABG--comparison with TI myocardial spect]

To evaluate the clinical usefulness of MIBG scintigraphy, 25 CABG patients underwent myocardial imaging using MIBG and TI. The result of this study indicated that the sensitivity of the MIBG was equivalent to that of the stress TI in detection of ischemic lesions. In spite of successful recanalization, only 14 patients showed improvement of MIBG uptake, indicating that MIBG is not useful for detecting myocardial ischemia just after CABG. The decreased postoperative uptake of MIBG suggests that the CABG procedure may have caused denervation of the region.

Identification of rat urinary kinin as bradykinin

Bradykinin (BK)-like activity, which was detected by BK-enzyme-immunoassay, was purified from 80 ml of ureter urine of Sprague-Dawley rats by Sephadex G 25 chromatography, FPLC, and reversed phase HPLC. The purified kinin fraction showed the same retention time as authentic BK on HPLC and produced contraction of isolated rat uterus, the contraction being suppressed by a B2-antagonist Hoe140. There was no other kinin detected on the HPLC at the corresponding retention time to kallidin, arginyl-BK or T-kinin. The peptide showed an amino acid sequence identical to that of BK by amino acid sequence analysis.

Tissue and serum pepsinogen I and II in gastric cancer identified using immunohistochemistry and rapid ELISA

AIMS

To investigate the immunohistochemical expression and the serum concentrations of pepsinogen I and II in different histological types of gastric cancer as compared with other gastric disorders.

METHODS

Formalin fixed, paraffin wax embedded tissue specimens of 38 gastric cancers obtained from surgical cases were used for the immunohistochemical studies performed with the avidin-biotin complex method using monoclonal antibodies against purified pepsinogen I and II. Pepsinogen concentrations from serum obtained from the above patients, from patients with various other gastric disorders, and from normal controls were measured with a rapid non-radioactive one step enzyme linked immunosorbent assay (ELISA).

RESULTS

Eight of 38 (21%) and seven of 38 (18%) gastric carcinomas showed immunoreactivity to pepsinogen I and pepsinogen II, respectively, without any correlation to histological classification or differentiation. Decreased pepsinogen I concentrations and low pepsinogen I:II ratios were found specifically in cases of gastric carcinoma and polyp, in good accordance with the immunohistochemical results.

CONCLUSIONS

Low serum pepsinogen I concentrations and a low pepsinogen I:II ratio are predictive of gastric neoplasia, correlating with low tissue immunoreactivity to monoclonal antibodies raised against pepsinogen I and II. For mass screening of gastric disease including carcinoma, ELISA using a one step immunoassay performed in the present study is a rapid and reliable non-radioactive method of detecting serum pepsinogen. In addition, immunohistochemical studies showed that pepsinogen production may be increased or diminished as a result of tumour histogenesis, depending on the area of origin and the processes of cell transformation and dedifferentiation.

Diquat increases cysteine proteinase inhibitors greatly in rat plasma and tissues

Biochemical and gross pathological effects of diquat were studied with special attention to cysteine proteinase inhibitor level which was often increased in acute and chronic disorder. Diquat was fed continuously to rats at the dose of 1000 ppm in the diet. After 10 days, anorexia and severe diarrhea were observed but epistaxis and hypokinesia were not apparent. The rats were killed after feeding the diet for 13.5 days and plasma components such as acute phase reactant proteins and some vitamins which act as antioxidants were examined. The results showed that alpha-cysteine proteinase inhibitor (alpha-CPI) increased to 9-fold and vitamin C radical increased to 1.6-fold, whereas alpha 1 proteinase inhibitor (alpha 1-PI) decreased to 0.9-fold and vitamins C and E were the same as the control. Among three components of alpha-CPI, the T kininogen level in intoxicated rat plasma was about 20-fold, whereas the high molecular weight kininogen level was about 2-fold of the control. Diquat also enhanced the cysteine proteinase inhibitor (CPI) level to 20-fold in kidney and to 7- to 10-fold in the other organs. The large increment of T kininogen in these organs was also confirmed immunologically. The kidney showed a granular degeneration and its weight increased to 1.2-fold of control. The other organs showed neither gross pathological alteration nor weight change, compared with the control. The diquat distribution was highest in spleen and next highest in kidney among several organs. These results were compared with those caused by paraquat.

Antigen immunohistochemistry of renal cell adenomas in autopsy cases: relevance to histogenesis

Eighty-three kidneys from autopsy cases, all more than 60 years of age, were used in the present studies. Three millimeter-thick step slices from all kidneys were embedded in paraffin, and serial sections from all blocks used for the immunohistochemical demonstration of Leu M1 (leukocyte membrane antigen) and LTA (Lotus tetragonolobus agglutinin) in cells of proximal convoluted tubular origin, and PNA (peanut agglutinin) and EMA (epithelial membrane antigen) in cells of distal convoluted tubular origin. The ABC staining method was used in all cases. A total of 65 renal cell adenomas found in 31 of the 83 kidneys consisted of 40 papillary, 20 tubular and 5 solid type lesions. The sizes of these renal cell adenomas were from 0.6 to 5 mm in diameter and compression of neighboring tissues was characteristic. Papillary renal cell adenomas were positive in their cytoplasms for Leu M1 and LTA in 7 cases and at their cell membranes for PNA and EMA in 33 cases. The respective figures for tubular renal cell adenomas were 6 cases for Leu M1 and LTA and 14 cases for PNA and EMA. All solid renal cell adenomas were positive in their cytoplasms for PNA and EMA. The immunohistochemical results thus indicated 13 of 65 lesions to have a proximal convoluted tubular cell origin and 52 to be possibly derived from distal convoluted tubules or collecting ducts. A role for metaplasia, however, could not be ruled out.

Acute-phase reactant proteins and antioxidants in rats intoxicated chronically with paraquat

Paraquat dichloride at 250 ppm in the diet was fed continuously to rats. Though no apparent effect of paraquat was observed until 10 d, some rats then began to show several symptoms such as diarrhea, anorexia, epistaxis, and hypokinesia, and in some cases rats died after this period. The biochemical examination of plasma components revealed appreciable changes in the concentrations of an acute-phase reactant protein and some vitamins that act as antioxidants. alpha-Cysteine proteinase inhibitor increased by 5-fold, and vitamin C and its radical increased by 1.5- and 1.7-fold, respectively, whereas alpha 1 proteinase inhibitor decreased slightly. Paraquat enhanced the cysteine proteinase inhibitor levels in lung, liver, and kidney by 6.2-, 6.0-, and 4.5-fold of control, respectively. Among three components of alpha-cysteine proteinase inhibitor, the T kininogen level of treated rat plasma was about eight-fold higher than control, whereas the high-molecular-weight kininogen level was unchanged. The large increment of T kininogen was also seen in lungs of the treated rats.