A case of I-cell disease

A case of I-cell disease is reported. The patient suffered from several episodes of pneumonia, and died of pneumonia at 12 months of age. Tissue specimens obtained at autopsy were stained with colloidal iron to demonstrate acid mucopolysaccharides. Characteristic foamy changes were observed in organs such as the heart, kidneys, liver, spleen and brain. An interesting finding in this case was that not only the interstitial cells but the alveolar epithelium in the lung showed the same foamy changes. The major causes of death of patients with I-cell disease are congestive heart failure and recurrent respiratory infections. However, there have been few reports on the histological changes in the lungs, and none have described the changes in the alveolar epithelium. Further cases must be investigated to examine the pathological relation between the histological changes in the lungs and the cause of death, because recurrent respiratory infections are the major contributor to death in patients with I-cell disease.

Finite element analysis of the relationship between clasp dimensions and flexibility

A parameter study with use of the finite element method was conducted for examination of the relationships between the shape parameters of a clasp (width and thickness at the base and tip of the clasp) and its displacement or stress. By synthesis of these relationships, a simple formula defining the clasp tip displacement in terms of clasp dimensions ("displacement formula") was obtained. A stiffness parameter "Fd" (the load producing a 1-mm displacement of the clasp tip) was proposed, and a formula defining Fd in terms of shape parameters was derived from the displacement formula. Fd would be a practical parameter for the definition of clasp retention, and the present formulae appear to be useful tools for investigation of the retention of removable partial dentures.

Enhanced expression of the sis and c-myc oncogenes in human meningiomas

In 19 human meningiomas (14 primary and four recurrent tumors and one tumor transplanted into athymic nude mice), oncogene expression, amplification, and rearrangement, and loss of heterozygosity on chromosome 22 were examined. Compared to nontumor brain tissue, there was greater than a fivefold expression of the sis oncogene in six (40%) of 15 tumors studied and of the c-myc oncogene in 12 (63%) of the total 19 tumors. Expression of the sis gene was lower in the recurrent tumors than in the primary cases, and there was no detectable expression in anaplastic meningioma cells. Rearrangement of the sis gene was found in one meningioma. Loss of heterozygosity on chromosome 22 was detected in two of the five informative heterozygous cases. Expression of the c-myc gene was higher in cases with a loss of heterozygosity than in those without. These results suggest that the sis and c-myc oncogenes are associated with tumorigenicity and that c-myc may induce meningiomas through loss of the putative tumor suppressor gene.

Transforming genes from familial adenomatous polyposis patient cells detected by a tumorigenicity assay

We tried to detect oncogenes associated with familial adenomatous polyposis by a tumorigenicity assay in nude mice. One polyp and two peripheral blood lymphocyte DNAs out of 12 samples from patients induced Alu-positive tumors. Lymphocyte DNAs from one of 5 healthy people also showed tumorigenic activity. The transforming genes of polyps from a patient and lymphocytes from a normal person were found to be the human N-ras gene. Since these N-ras genes were amplified in nude mouse tumors and did not show any alterations in the nucleotide sequences around codons 12 and 61, it is likely that the tumors were induced by the amplified normal N-ras genes. The transforming sequences from two patients' lymphocytes did not hybridize with 12 known oncogene probes, suggesting that these two genes are novel oncogenes or genes for which we have not yet examined the homology. One oncogene derived from a patient's lymphocytes was partially cloned and shown to be located on human chromosome 7. This gene did not hybridize with the met and erbB1 genes, which are potential oncogenes located on chromosome 7. These data indicate that this gene is a new oncogene.

[Intramural duodenal hematoma: a case report]

A 55-year-old male patient with acute onset of abdominal pain was examined. He had no apparent history of abdominal trauma or bleeding tendency. MRI showed three layered architecture, so-called "ring sign" distinctive of hematoma. MRI seemed to be very useful in non-invasively diagnosing intramural duodenal hematoma.

Alterations of mouse proto-oncogenes in sarcomas induced after transplantation of human tumors in athymic nude mice

During serial subcutaneous transplantation of several types of human tumors into nude mice, the local development of malignant mouse-specific sarcomas has been observed. Although the frequency of sarcoma induction is low, this phenomenon is very important because the mouse-specific sarcomas completely replaced the human tumors during serial transplantation. The DNA of five independently induced mouse-specific sarcomas was transfected into NIH/3T3 cells in order to detect oncogenes associated with mouse-specific sarcoma induction. Two of these DNAs were found to carry activated mouse c-N-ras and c-Ki-ras genes. The sequence analysis of the molecularly cloned mouse c-N-ras oncogene showed a single nucleotide transition from G to A at the 12th codon. This results in substitution of aspartic acid for glycine at this position. The mouse c-myc gene was also found to be amplified in a sarcoma. In these mouse sarcoma DNAs, human Alu sequences were not detected. These data strongly suggest that the mouse-specific sarcomas were not induced by the transfer of human transforming sequences but by the alterations of mouse proto-oncogenes.

Trial patterns for selection of major connectors

A method for selecting the individually suitable form and location of major connectors for partially edentulous patients is described. Light-polymerized resin patterns are alternately placed in the patient's mouth, and the most suitable location and the form of the major connector are selected. This trial pattern method makes it possible to better address the problems posed by difficult removable partial denture patients.

[Tooth tapping frequency of young and elderly subjects]

Tooth tapping frequency was measured in young (21-29 years) and elderly (61-67 years) subjects. They were asked to continue the maximal frequent tapping during 1 min., and their mandibular movement were measured with a Mandibular Kinesiograph. The results are as follows: 1. Each phase of closing, occluding, opening and cycle was prolonged at the terminal of the 1 min. tapping. That is, tapping frequency decreased. Young subjects had 4.6 Hz tapping frequency and 2.7 Hz for elderly subjects. 2. Although the opening phase per cycle and the closing were not changed in spite of the tapping continuity, the occluding one increased at the terminal of the 1 min. tapping. 3. No difference existed between the young subjects and elderly in the maximal velocity of the mandibular movement at the opening and closing. Opening velocity was larger than closing velocity at the young subjects.

[3 cases of ectopic ureteral orifice terminating in the seminal vesicle; efficacy of CT]

We present three cases of ectopic ureteral orifice terminating in the seminal vesicle. The enlarged seminal vesicle, ipsilateral renal agenesis or hypoplasia and the absence of normal ureteral orifice are the triad of CT findings in this disease.

[Magnetic resonance imaging of bladder tumors: superiority of serial "Fast SE" assisted by Gd-DTPA in tumor staging]

Eighteen cases with bladder tumors were examined by means of superconducting MRI. Sequences used were spin echo (TR/TE (msec) = 500/20 as T1WI (weighted image) and 1500/80 as T2WI) and serial "fast spin echo (fast SE)" pre/post Gd-DTPA administration. "Fast SE" was a new technique offering a distinct T1WI (TR/TE = 100/14, utilizing a 14 second breath hold). Slice thickness of "fast SE" was 10 mm and slice plane was selected perpendicular to the tumor base to detect the extent of invasion. Serial scan of "fast SE" was performed before and immediately after 0.1 mmol/kg Gd administration. Scanning was completed before the bladder was opacified by Gd. Tumor and normal mucosa were both markedly enhanced whereas the surrounding muscle layer remained hypointense. On delayed scan, the elevated character of the tumor was outlined by opacified urine but the distinction between the mucosa and the muscle layer became unclear. Total cystectomy (TC) was performed in 6 of 18 cases and pathological tumor extension was correlated with MR findings. Transurethral resection (TUR) was performed in the remaining 12 patients, and the tumor extension was assessed by follow-up biopsy after TUR. Intact liner hypointensity indicated superficial lesions (= less than pT2), while disruption of the linear hypointensity corresponded pathologically to deep muscle invasion (= greater than pT3a). Accuracy of serial "fast SE" in tumor staging was 94% (17/18). Serial "fast SE" allowed the distinction of superficial from invasive tumors more accurately than conventional studies, and therefore assisted in choosing the correct operative method.

[Electromyographic study on masticatory function of the telescope denture wearers in the Kennedy Class II mandible]

Masticatory function of 10 telescope denture wearers in the Kennedy class II mandible patients was evaluated with electromyography. Electromyographic activity during mastication with kamaboko and peeled raw carrot was recorded from bilateral masseter and the anterior part of temporal muscles at each interval: Before treatment, immediately after denture insertion and 2, 4, 6, 8 weeks after respectively. Mean of duration, interval and cycle of EMG activities, coefficient of variation and average variation were calculated. The results were as follows: 1. Means of duration and cycle times decreased immediately to 2 weeks after denture insertion. 2. EMG activities during raw carrot chewing became regular immediately to 2 weeks after denture insertion, and within 4 weeks in kamaboko chewing. These results suggest that telescope dentures would be adapted to stomatognathic system within short period after denture insertion.

[Prosthodontic treatment for a partial mandibulectomy patient. A mandibular non-reconstructed case]

One of the most consistently frustrating areas of maxillofacial rehabilitation is the treatment of patients who have had radical cancer surgery of the tongue, floor of the mouth, and mandible. The patient described in this report, was a 66-year-old man who had squamous cell carcinoma of the right jaw. The right body of the mandible distal to the right cuspid was resected, and this part of the mandible was not reconstructed. For this mandibulectomy patient, we have treated with the removable partial denture using 30 degree teeth and TS telescope crown as retainer, registrating maxillomandibular relation with Gothic arch tracer and MKG. In addition, masticatory function in this patient was evaluated on tooth contact, tapping pattern, masticatory efficiency and rhythm of mastication. Consequently, 4 to 8 weeks later, tapping pattern and centric occlusion was stabilized, and masticatory function was improved. We will continue to observe this case in long term.

Increased level of mitochondrial gene expression in polyps of familial polyposis coli patients

To elucidate the mechanism of polyp formation in familial polyposis coli patients, cDNA clones, expressed differently between normal colonic mucosae and polyps, were screened. Three polyp-derived cDNA clones showed increased levels of transcription under neoplastic conditions. Among them, clone P6 was determined to be derived from the mtDNA encoding parts of subunit 1 of NADH dehydrogenase and 16S rRNA. The number of copies and restriction enzyme patterns of the mtDNA did not vary in either normal or neoplastic tissues, and a level of different mitochondrial mRNA was increased in the same proportion, suggesting a change in the rate of synthesis and/or degradation of the mtRNA. No cDNA clone which was expressed higher in normal colonic mucosae than in polyps was isolated from the cDNA library derived from normal mucosae.

[Effect of various contrast media on platelet aggregation--an in vivo study]

Recently, some radiologists using non-ionic contrast media for angiography have noted the increased tendency of thrombus formation in the injection syringe or angiographic catheter contaminated with blood. In vitro studies by some authors have shown that non-ionic contrast media had only a slight anticoagulative effect as compared with ionic contrast media. But the in vivo studies comparing the anticoagulative effect of both ionic and non-ionic contrast media have not been performed previously. We investigated the effect of non-ionic and ionic contrast media on platelet aggregation in 40 patients undergoing angiography. The in vivo study revealed a negligible influence of both non-ionic and ionic contrast media on systemic platelet aggregation. The dose of contrast media also showed no significant correlation with platelet aggregation. Our study suggests that the data from in vitro experiments cannot be extended to in vivo study as for the relationship between contrast media and their anticoagulant effect.

Multi-step neoplastic transformation of normal human fibroblasts by Co-60 gamma rays and Ha-ras oncogenes

As reported previously (Namba et al., 1985; Namba, 1985), normal human fibroblasts were transformed into immortal cells with abnormal karyotypes by Co-60 gamma-ray irradiation. These immortally transformed cells (KMST-6) showed no clonability in soft agar and were not tumorigenic. However, by treatment with Ha-ras oncogenes derived from a human lung carcinoma or Harvey murine sarcoma virus, the KMST-6 cells acquired elevated clonability in soft agar and transplantability in nude mice. All the tumors produced grew progressively without showing regression and killed the mice. The tumors were also serially transplantable into other mice. The Ha-ras oncogene alone did not convert normal human fibroblasts into either immortal or tumorigenic cells. Our current data suggest that gamma rays worked as an initiator of carcinogenesis in normal human cells, giving rise to chromosome aberrations and immortality, and the Ha-ras oncogene played a role in the progression of the immortally transformed cell population to a neoplastic one showing enhanced colony formation in soft agar and tumorigenicity in nude mice.

Intraarterial digital subtraction angiography with carbon dioxide: superior detectability of arteriovenous shunting

Intraarterial digital subtraction angiography (IADSA) with carbon dioxide (CO2) was performed on 41 patients with liver or renal diseases. CO2 produced no hypersensitivity reactions, and the pain or feeling of warmth was relatively mild compared with iodinated contrast media. Although the image quality of the arterial or capillary phase was inferior to that with iodinated contrast media, the detectability of arteriovenous shunting was excellent. IADSA with CO2 may become an effective method for detecting arteriovenous shunting which cannot be demonstrated with conventional angiography or DSA with iodinated contrast medium.

[Long-term maintenance of human gall-bladder epithelia as xenografts following explant organ culture]

The purpose of present study is to establish a method that should enable us to keep a human gall-bladder epithelial tissue alive for a period long enough to observe morphological change after an exposure to a certain carcinogenic agents. Human gall-bladder epithelia obtained from surgically resected specimen were kept as an explant organ culture in vitro for the first 2 weeks. They were, then, xenotransplanted to the subcutaneous (S.C.) space of the athymic nude mice. The gall-bladder tissues obtained from 7 cases of cholecystolithiasis and 1 case of cholecysto-choledocholithiasis were used as materials in the present study. And the longest survivor among them in the nude mice was extensively studied in the present paper. After an interval of 4 to 27 weeks, the xenografts were recovered from the recipient mice and studied by light microscopy and histochemistry. The morphological changes of the explant epithelia during the organ culture were also studied. Parts of the explants were implanted in 6 nude mice. Each of the mice received 3 pieces of explants on the s.c. space in both of their flanks. All xenografts showed subcutaneous cyst formation. The cyst obtained 4 weeks after the implantation was consisted of a monolayer of cuboidal epithelial cells and those recovered from the recipient mice 24 and 27 weeks after the implantation were consisted of well growing columnar and cuboidal epithelial cells. In addition, sinus-like structures were observed beneath the cystic epithelia. The viability of the cells was excellent.(ABSTRACT TRUNCATED AT 250 WORDS)

Transforming genes in human hepatomas detected by a tumorigenicity assay

Two transforming sequences in human hepatomas were detected by means of a tumorigenicity assay in nude mice using transfected NIH3T3 cells. Through hybridization with known oncogene probes, the transforming gene in one hepatoma was found to be the human hst gene. The transforming sequence in the other hepatoma showed no sequence homology with any of the oncogenes examined.

Distribution of basal lysosomes in exocrine acinar cells

We examined the distribution of trimetaphosphatase (TMPase)-positive basal lysosomes in pancreas, parotid, submandibular, sublingual, and exorbital lacrimal glands from rats, rabbits, and guinea pigs. The location of the basal lysosomes was compared to that of the acid phosphatase (AcPase)-positive lysosomes. In all of the tissues examined from rat and rabbit, AcPase activity was localized primarily to the Golgi region. Reaction product was localized in GERL, immature secretory granules, and lysosomes lying adjacent to the Golgi apparatus. TMPase activity was found in basal lysosomes and in occasional elongated lysosomes adjacent to the Golgi apparatus. In guinea pig, the distribution of TMPase activity was identical to that seen in the other two species, but a significant number of lysosomes in the basal region of the cells also contained AcPase activity. These results confirm and extend our previous finding (J Histochem Cytochem 31:1209, 1983) that exocrine acinar cells possess two distinct populations of lysosomes. The lysosomes in the Golgi region contain both AcPase and TMPase activity, whereas those in the basal portion of the cells are reactive predominantly for TMPase. The functional significance of the two populations of lysosomes is not understood at present.

Change in pulmonary and systemic circulation in acute ventricular septal defect

The correlation between left to right ventricular (L-R) shunt flow and other hemodynamic changes was studied in 16 dogs with an acute ventricular septal defect (VSD) and normal pulmonary vascular bed. The interventricular shunt flow was measured directly with a specially designed electromagnetic flowmeter probe, where the area of the VSD was constant. The sudden presentation of VSD increased pulmonary arterial pressure, pulmonary flow and left ventricular end-diastolic pressure. L-R shunt flow was not changed significantly by atrial pacing except when the rate was increased to over 200/min. Dogs with a VSD were treated with isoproterenol and dextran to vary the shunt flow and hemodynamic parameters. L-R shunt flow was decreased by isoproterenol and increased by dextran loading. The percentage changes of L-R shunt flow from pre-drug values correlated well with the change in left ventricular end-diastolic pressure (r = 0.75) and the ratio of pulmonary to systemic vascular resistance (r = -0.73). Change in total pulmonary vascular resistance had a greater effect on L-R shunt flow than did a change in systemic vascular resistance, whereas a change in aortic flow had less effect (r = 0.35) on L-R shunt flow than did a change in preload and afterload. The time to peak LV dP/dt, as an index of cardiac contractility, and heart rate were not correlated with the relative change in L-R shunt flow. These results indicate that L-R shunt flow induced by the sudden presentation of a VSD varied with changes in the pulmonary and systemic circulation.

Colon carcinoma K-ras 2 oncogene of a familial polyposis coli patient

The DNA of a colon carcinoma-derived cell line (KMS-4) and that of skin fibroblasts from a familial polyposis coli patient were transfected into NIH3T3 cells in order to detect oncogenes associated with the disease. No transformation was observed with the normal skin fibroblast DNA, while the KMS-4 cell DNA was able to transform NIH3T3 cells. Through hybridization with known oncogene probes, the KMS-4 transforming gene was found to be a human activated c-K-ras 2 oncogene. Sequence analysis of the molecularly cloned KMS-4 c-K-ras 2 oncogene showed a single nucleotide transition from G to T at the 12th codon. This results in substitution of cysteine for glycine at this position. On using labeled synthetic oligonucleotides to detect the mutation in codon 12, we found the G to T transition in colon carcinoma cells. This suggests that activation of the c-K-ras 2 oncogene could be associated with colon carcinoma induction.

Activated N-ras in a human rectal carcinoma cell line associated with clonal homozygosity in myb locus-restriction fragment polymorphism

An N-ras transforming gene was detected in human rectal carcinoma-derived cells (7060) and molecularly cloned. The genetic lesion responsible for the transforming activity of the 7060 oncogene was localized to a single nucleotide transition from A to T in codon 61 of the predicted protein. This lesion in the second exon results in substitution of histidine for glutamine at this position. We also found an EcoRI restriction fragment length polymorphism, consisting of two alleles, of the human c-myb gene. The 7060-transformed epithelial cells showed the homozygous phenotype, while normal fibroblasts of the same patient showed the heterozygous phenotype. This suggests a relationship between the phenotypic change in the c-myb locus and the induction of the 7060 tumor.

Effects of interventricular shunt on indices of left ventricular function

The accuracies of indices of left ventricle function were examined in an open-chest model in dogs with and without a ventricular septal defect, in which the ventricular shunt was opened and reclosed by a specially designed flowmeter probe with a cap. The systolic time interval, the maximal rate of pressure development in the left ventricle (+LV dP/dt), +LV dP/dt corrected for the isometric pressure (+LV dP/dt/Pd), and the time to +LV dP/dt (t-dP/dt) were determined by recording the aortic flow, ventricular shunt flow, aortic pressure, pulmonary arterial pressure, and left ventricular pressure. The isometric contraction time, the preejectional period, and the ejection time shortened with decrease of the mean aortic pressure and aortic flow, and the mean pulmonary arterial pressure increased after opening the ventricular shunt. When the pulse was varied by atrial pacing, the systolic time interval was affected in dogs both with and without a ventricular septal defect, but "isometric contraction time" was not affected in animals with a ventricular septal defect. Dopamine and methoxamine were used to evaluate the effects of the inotropic state and afterload on these indices. The extents of the changes in the systolic time interval and +LV dP/dt were different in animals with and without a ventricular septal defect, but the changes in preejectional period/ejection time, +LV dP/dt/Pd and t-dP/dt were similar in the two conditions. These results suggest that the systolic time interval and the indices of left ventricular pressure are useful in assessment of cardiac function only in certain conditions.

[Clinical studies on cefixime in pediatrics]

A clinical study of cefixime (CFIX), a new oral cephalosporin, was carried out to evaluate its therapeutic effectiveness on bacterial infections in children. CFIX was orally administered to 13 patients including 6 with upper respiratory tract infection (RTI), 3 with pneumonia, and 1 each with bronchitis, otitis media, skin abscess, and urinary tract infection (UTI). The daily dosage per kg bodyweight ranged from 5.1 to 17.4 mg (average: 8.7 mg), and was given in 2 or 3 divided doses per day for 3 to 10 days (average: 5.8 days). The clinical response was excellent in 4 (30.8%), good in 7 (53.8%) and poor in 2 (15.4%), with an overall efficacy rate of 84.6%. Bacteriological efficacy was good, and 6 of the 8 identified causative organisms were eradicated. Side effects were observed in 3 children, i.e., loose stool in 1 and transient elevations of GOT and GPT in 2. The above results suggest that CFIX is a useful new oral cephalosporin for the treatment of bacterial infections in children.

[Clinical experience with ceftizoxime suppositories in bacterial infections in children]

A clinical trial of ceftizoxime suppositories (CZX-S) was performed to evaluate the therapeutic effectiveness in children with bacterial infection. The subjects were 10 children comprising 4 with pneumonia, 3 with lacunar tonsillitis, 2 with pharyngitis, and 1 with UTI. They were given 1 suppository containing either 125 mg or 250 mg of CZX 2 to 4 times a day. The daily per kg body weight dose ranged from 17.1 to 60.0 mg. The result was "markedly effective" in 3, "effective" in 6, and "failure" was recorded in 1. Bacteriologically, successful eradication of causative organisms was confirmed in all the 4 children who underwent the test. No clinical side effects were observed. The only laboratory test abnormality recorded in a single patient was eosinophilia, which was not definitely ascribable to CZX-S. In conclusion, CZX-S have proved to be a clinically safe and effective antibiotic preparation in infantile infection, even in children whose treatment with conventional antibiotics is associated with difficulties.

Magnetic resonance imaging of fluorine in rats infused with artificial blood

An MRI pulse sequence has been developed that enables the visualization of a perfluorocarbon (PFC) emulsion in the vascular system of rats. Images were made at 0.12T on a clinical imaging system using a small receiver coil, at intervals of approximately 2 hours, two days, two weeks, and two months after replacement of 50% of total blood volume. The most successful technique produced PA projections of the entire torso for both the fluorine and proton components. Direct comparison allowed identification of PFC in heart, lung, liver, spleen, and large vessels both in vivo and postmortem. Potential clinical applications to vascular imaging are discussed.

Effect of respiratory acidosis on ventricular shunt flow and hemodynamics in dogs with ventricular septal defect

The effects of respiratory acidosis on ventricular shunt flow and hemodynamics were studied in 20 anesthetized dogs with a ventricular septal defect and a normal pulmonary vascular bed. The interventricular shunt flow was measured directly by using a specially designed electromagnetic flow probe. Respiratory acidosis was produced by hypoventilation and tachypnea with constant minute volume. Hypoxemia was also induced by hypoventilation, but not by tachypnea with constant minute volume. Systemic vascular resistance was increased in severe hypoventilation at 100 and 50 ml of tidal volume, and tachypnea at 100 ml of tidal volume. However the increase of pulmonary vascular resistance was observed in only severe hypoventilation: arterial pH 6.9, PaO2 24 mmHg, and PaCO2 88 mmHg. Left to right ventricular shunt flow and pulmonary blood flow were increased significantly with no change of systemic blood flow in both conditions of respiratory acidosis. The diastolic fraction of shunt flow was increased significantly. These findings indicate that the increase of left to right shunt flow in respiratory acidosis might be one of the risk factors of congestive heart failure for the patients with ventricular septal defect.

Effects of two major activating lesions on the structure and conformation of human ras oncogene products

ras oncogenes are frequently activated in human tumors by mutations at codon 12 or 61 in their coding sequences. To investigate how these subtle alterations exert such profound effects on the biologic activities of these genes, we studied structural and conformational properties of human ras-oncogene-encoded 21-kDa proteins (p21s). We observed striking differences in the electrophoretic mobilities of the proteins under reducing and nonreducing conditions. These findings imply that intramolecular disulfide bonds affect native p21 conformation. The two activating lesions were shown to induce distinctly different alterations in p21 electrophoretic mobility that were unmasked only under reducing conditions. These results suggest that regions of the molecule containing such alterations are either not exposed or under conformational constraints in the native p21 molecule. We confirmed the opposing effects on protein mobility induced by the two activating lesions by using a recombinant gene containing both lesions. The recombinant gene's high-titer transforming activity further established that the two lesions do not negatively complement one another with respect to transforming-gene function. Our findings of distinct alterations in electrophoretic mobilities of position-12- and position-61-altered p21 molecules should be applicable to the rapid immunologic diagnosis of ras oncogenes in human malignancies.

Magnetic resonance imaging following unilateral occlusion of the renal circulation in rabbits

Magnetic resonance studies at 0.12 T were performed following acute unilateral occlusion of the renal artery or vein in rabbits. Prior to occlusion, in vivo and in vitro relaxation times of the renal cortex and outer medulla were similar. After venous occlusion, T1 and T2 were prolonged on the occluded side, while the contralateral side remained unchanged. After arterial occlusion, the outer medulla of both the occluded and contralateral kidney exhibited prolonged relaxation times. There was a significant linear correlation between T1, T2, and the water content of the tissue. The authors conclude that quantitative in vivo relaxation times may eventually prove to be useful in diagnosis, although at present they are less reliable than those obtained in vitro.

A position 12-activated H-ras oncogene in all HS578T mammary carcinosarcoma cells but not normal mammary cells of the same patient

Among 21 human mammary tumors analyzed for transforming genes by transfection of NIH/3T3 cells, only DNA of a carcinosarcoma cell line, HS578T, registered as positive. A Harvey (H)-ras oncogene identified in this line was cloned in biologically active form and the activating lesion was identified as a single nucleotide substitution of adenine for guanine in the 12th codon. This results in substitution of aspartic acid for glycine at this position of the p21 coding sequence. Knowledge that this alteration creates a restriction site polymorphism for Msp I/Hpa II in the H-ras protooncogene made it possible to survey for the presence of the activated H-ras allele in normal cells as well as in clonally derived tumor cell lines of the same patient. We demonstrated the presence of unaltered H-ras alleles in normal HS578 cells. In contrast, every clonally derived HS578T tumor cell line analyzed contained the H-ras oncogene possessing the genetic alteration at position 12. These findings establish that activation of this oncogene was the result of a somatic event selected within all HS578T tumor cells.

Mechanism of activation of an N-ras oncogene of SW-1271 human lung carcinoma cells

An N-ras-related transforming gene was detected in the human lung carcinoma cell line SW-1271 and molecularly cloned. The lesion responsible for its acquisition of transforming activity was localized to a single nucleotide transition from A to G in codon 61 of the predicted protein. This lesion in the second exon results in the substitution of arginine for glutamine at this position. These findings, together with previous studies, indicate that the activation of ras oncogenes in human tumors is most commonly due to point mutations at one of two major "hot spots" in the ras coding sequence.

Ha-ras oncogenes are activated by somatic alterations in human urinary tract tumours

DNA-mediated gene transfer (transfection) studies using NIH 3T3 cells as recipients have demonstrated the presence of transforming genes (oncogenes) in diverse human tumours. A large proportion of oncogenes so far detected by DNA transfection are related to the Ha-ras onc gene of Harvey (and BALB) murine sarcoma viruses (MSV), Ki-ras, the oncogene of Kirsten MSV, and a third member of the ras gene family, N-ras. Individual tumours of many different organs have been associated with the activation of members of the ras gene family. We now present the first systematic survey of human urinary tract tumours processed immediately after surgery, as well as normal tissues from the same patients, to detect the presence of such genes. We demonstrate activation of Ha-ras as an oncogene in around 10% of randomly selected urinary tract tumours as well as direct evidence that oncogene activation is the result of a somatic event which is selected for within the tumour cell population.

Vasoconstrictive effects of prostaglandin F2 alpha angiography on colonic lesions

In a study of 54 patients with a variety of lesions, prostaglandin F2 alpha pharmacoangiography produced vasoconstrictive effects in both neoplastic and inflammatory lesions of the colon. These effects occurred only at the affected sites and their immediate vicinity. Vasoconstriction seemed to correlate directly with the vascularity of the lesion, rather than with pathogenesis. Less marked vasoconstriction was seen in renal lesions. No vasoconstrictive effects were recognized in liver, soft tissue, or bone tumors. Thus prostaglandin F2 alpha acts as a vasodilator in normal human colonic vessels, while it acts as a vasoconstrictor in colonic lesions. The potential use of prostaglandin F2 alpha in the control of bleeding colonic lesions is also discussed.

Normal cells of patients with high cancer risk syndromes lack transforming activity in the NIH/3T3 transfection assay

Oncogenes capable of transforming NIH/3T3 cells are often present in human tumors and tumor cell lines. Such oncogenes were not detected in normal fibroblast lines derived from patients with several clinical syndromes associated with greatly increased cancer risk. Thus, germ-line transmission of these oncogenes does not appear to be the predisposing factor responsible for these high cancer risk syndromes.