The measurement of DNA content in Wilms' tumor and its clinical significance

DNA content analysis with paraffin-embedded tissue was performed by flow cytometry on extracted nuclei from 42 Wilms' tumors. DNA histograms showed diploid in 13, tetraploid in 12, and aneuploid in 17. The frequency of DNA aneuploid was 40.48%. The 2- and 5-year survival rates were 84% and 75.16%, respectively, for patients with the DNA diploid pattern; the 2- and 5-year DNA aneuploid survival rates were 47.06% and 41.18% (P < .03 and P < .05), respectively. The 2- and 5-year survival rates for DNA tetraploid were in between, both 55.90%. For patients with stage I and II, the difference in the 2- and 5-year survival rates between DNA diploid plus tetraploid and DNA aneuploid was even more significant (P < .004 and P < .002, respectively). Thus, DNA aneuploid is an important indicator of poor prognosis in Wilms' tumor, especially for stages I and II.

Evaluation of captopril renography with 99mTc-MAG3 in the diagnosis of renovascular hypertension

Eighty-one patients with suspected renovascular hypertension (RVH) were studied using 99mTc-MAG3 renography before and after administration of 25 mg captopril (CAP). Among the 81 cases, 22 were proven by renal arteriography or DSA. The results showed that by using CAP, the sensitivity and specificity of renography in RVH diagnosis increased from 66% to 72% and from 33% to 100%, respectively. We conclude that renography is a simple, noninvasive, sensitive and specific method for screening RVH and is suitable for use in hospitals with no gamma-cameras.

Cooling responses of finger in contact with an aluminum surface

Skin temperature (T sk) changes and subjective sensations of bare fingers touching a cold aluminum surface were determined in 25 subjects (12 female and 13 male). An 11-cm aluminum cube was placed in a mini-chamber, where chamber air and an aluminum cube were simultaneously cooled to -14, -5, and -1 degrees C, respectively. Subjects inserted their right hands into the chamber and pressed on the cube surface with three fingers with a force of 9.81 N (1 Kp). Exposure lasted until finger-skin temperature reached 0 degree C or was voluntarily ended by the subject. Regression equations with two exponential components were used to describe the relationship between T sk and exposure time. The short time constant (< 1 second) for the first part of the cooling curve is assumed to represent primarily thermocouple dynamics. The long time constant (> 20 seconds) for the second part of the cooling curve is interpreted as representing the rate of heat transfer from the tissues of the finger itself. Gender and cube-surface temperature had no significant effect on any of the time constants. Thermal sensation and pain sensation lacked a good correlation with the contact and T sk and T sk change.

Mapping of amino acid residues in the C mu 3 domain of mouse IgM important in macromolecular assembly and complement-dependent cytolysis

By analyzing the effects of single site mutations of a TNP-binding mouse IgM we have identified amino acid residues clustered in two regions in the C mu 3 domain that are important in the complement-dependent cytolytic activity of polymeric IgM. Some of the mutations also impaired IgM polymerization. For one of these clusters, D432G, P434A, and P436S, which lies on the fy2 and fy3 strands and their connecting loop, polymerization was little affected and the effect on the cytolytic activity of the polymer fraction was taken to imply direct involvement of the residue in C1 binding. The other cluster, involving residues D356A K361A and D417G, is situated at the other end of the C mu 3 domain closer to the center of the Fc mu disc. The D356A K361A and D417G mutations significantly impaired polymer formation, suggesting that these residues are necessary for proper folding or packing of the C mu 3 domains and may affect cytolysis only indirectly. Some other mutations had little or no effect on polymerization or cytolytic activity (E423A, E527G), whereas some mutations impaired only IgM polymerization without affecting cytolytic activity (D344A, K361A, K443A P544G). In others the defect in polymerization was so profound that only the monomer formed (H430A/N/Q and K438G). Our results also suggest that the C1 binding site of IgM is not strictly homologous to the C1 binding site of IgG. Although mutation of E318 of IgG has been shown to reduce its cytolytic activity, mutation of the homologous residue in IgM, E423, was without effect as were mutations of other flanking-charged residues. Proline at 436 in IgM and 331 in IgG may, however, be a common element.

Estimates of trace element intakes in Chinese farmers

Epidemiologic data on the average daily human dietary intake of the trace elements nickel, cadmium, molybdenum and silicon are scarce, worldwide, primarily because foods consumed vary widely over days and seasons. Available full year food allocation records for farmers in rural areas of China provide an unique opportunity to estimate dietary trace elements. In 1988, we measured the concentration of zinc, copper, iron, cadmium, nickel, molybdenum, silicon and selenium in different foods by using food samples collected from 232 villages (distributed among 21 communes). These measurements, combined with the food consumption information from existing food allocation records in each commune for an entire year, allowed us to estimate the average daily consumption of these trace elements by Chinese farmers. With one exception (an association of zinc and esophageal cancer), the variation of dietary trace elements did not show any association with mortality from several common diseases. The estimates for some of the dietary trace elements from some subpopulations were either less or more than current recommendations. No increases in mortality were found, however, from diseases normally associated with either dietary deficiencies or excesses of these elements.

Mapping of amino acid residues in the C mu 3 domain of mouse IgM important in macromolecular assembly and complement-dependent cytolysis

By analyzing the effects of single site mutations of a TNP-binding mouse IgM we have identified amino acid residues clustered in two regions in the C mu 3 domain that are important in the complement-dependent cytolytic activity of polymeric IgM. Some of the mutations also impaired IgM polymerization. For one of these clusters, D432G, P434A, and P436S, which lies on the fy2 and fy3 strands and their connecting loop, polymerization was little affected and the effect on the cytolytic activity of the polymer fraction was taken to imply direct involvement of the residue in C1 binding. The other cluster, involving residues D356A K361A and D417G, is situated at the other end of the C mu 3 domain closer to the center of the Fc mu disc. The D356A K361A and D417G mutations significantly impaired polymer formation, suggesting that these residues are necessary for proper folding or packing of the C mu 3 domains and may affect cytolysis only indirectly. Some other mutations had little or no effect on polymerization or cytolytic activity (E423A, E527G), whereas some mutations impaired only IgM polymerization without affecting cytolytic activity (D344A, K361A, K443A P544G). In others the defect in polymerization was so profound that only the monomer formed (H430A/N/Q and K438G). Our results also suggest that the C1 binding site of IgM is not strictly homologous to the C1 binding site of IgG. Although mutation of E318 of IgG has been shown to reduce its cytolytic activity, mutation of the homologous residue in IgM, E423, was without effect as were mutations of other flanking-charged residues. Proline at 436 in IgM and 331 in IgG may, however, be a common element.

Cancer among Hispanic males in south Florida. Nine years of incidence data

BACKGROUND

Dade County (Florida) is the largest county in the United States in which a majority of the population is Hispanic. To describe and compare cancer incidence among white and black Hispanic and non-Hispanic males in South Florida and to identify those sites showing important racial-ethnic differences between sub-groups, incidence rates were determined from 9 years of prospective population-based cancer surveillance data.

METHODS

All incident cancer cases diagnosed among male residents of Dade County for the period January 1, 1981, through December 31, 1989, were obtained from the statewide tumor registry for Florida, the Florida Cancer Data System. Race- and ethnic-specific age-standardized incidence rates and standardized rate ratios to compare rates among racial-ethnic subgroups for each site are presented.

RESULTS

Compared with white non-Hispanics, white Hispanic males had significantly higher rates of cancers of the liver, gallbladder, nasal cavity, penis, and thyroid; acute lymphocytic leukemia; and Kaposi's sarcoma. Significantly lower rates were found for cancers of the esophagus, stomach, colon, rectum, pancreas, lung, testes, bladder, and kidney, and for mesothelioma, melanoma, non-Hodgkin's lymphoma, and chronic lymphocytic leukemia. Black Hispanics had significantly lower rates only of cancers of the esophagus, lung, and prostate than did black non-Hispanics.

CONCLUSION

Differences were found in incidence rates by race-ethnicity; while incidence rates for most sites among white Hispanic males were lower than among white non-Hispanics, higher rates for several sites are of particular concern and merit further investigation to determine differences in risk factors and exposures.

Epstein-Barr virus (EBV)-encoded membrane protein LMP1 from a nasopharyngeal carcinoma is non-immunogenic in a murine model system, in contrast to a B cell-derived homologue

Epstein-Barr virus (EBV)-encoded LMP1 gene derived from a nude mouse passaged nasopharyngeal carcinoma (NPC) of Chinese origin (C-LMP1) and its B cell (B95-8 prototype)-derived counterpart (B-LMP1) were compared for their ability to induce tumour rejection in a mouse mammary adenocarcinoma system. Each of the two LMP1 genes was introduced individually by retroviral vectors into a non-immunogenic mammary carcinoma line, S6C, that originated in an ACA (H-2f) mouse. Syngeneic ACA mice were immunised for 3 consecutive weeks with irradiated B- or C-LMP1 expressors or control cells. The immunised and control mice were then challenged with graded numbers of viable cells from the corresponding cell line. Only the B-LMP1 expressing cells were highly immunogenic. Up to 10(5) cells were rejected in pre-immunised mice, whereas at least 10(2) cells grew in non-immunised controls. No rejection response was detected against the C-LMP1 expressing cells which grew equally well in control and immunised mice, with a minimum inoculum of 10(2) cells in the majority of the clones. In a previous study, we found numerous sequence differences between B- and C-LMP1. The question of whether any of these differences is related to the non-immunogenicity of C-LMP1 needs further investigation. Meanwhile, our findings raise the possibility that the NPC cells may escape host rejection by the development of a non-immunogenic LMP1 variant under the impact of immunoselection.

Characterization of somatostatin receptors on human neuroblastoma tumors

Neuroblastoma is the most common extracranial solid tumor of children. Neuroblastoma tumors derive from the neural crest and synthesize neurotransmitters including the neuropeptide somatostatin. This study was designed to characterize somatostatin receptors both in primary neuroblastoma tumors and in two neuroblastoma cell lines, SKNSH and IMR32. Somatostatin receptors were identified in 6 of 7 Stage I and II compared to 7 of 19 Stage III and IV tumors. Down-regulation of somatostatin receptor binding was observed in five tumors during disease progression. A lack of high affinity binding of somatostatin was identified as a poor prognostic indicator; negative binding correlated with advanced disease and death. Somatostatin receptor binding was observed in the IMR32 cell line, but not in the SKNSH cell line. IMR32 cells demonstrated a single class of high affinity binding sites for both somatostatin and a synthetic analogue, octreotide (Kd 0.16 +/- 0.05 nM and 0.89 +/- 0.23 nM, respectively). Somatostatin and octreotide inhibited both vasoactive intestinal peptide-mediated and forskolin-mediated cyclic AMP accumulation in IMR32 cells. Somatostatin and octreotide inhibition of signal transduction was attenuated by pretreatment of the cells with pertussis toxin. Octreotide inhibited proliferation of IMR32 cells by 70% in a 6-day culture. In contrast, octreotide did not exhibit high affinity binding in SKNSH cells and had no effect on cyclic AMP accumulation or on proliferation in SKNSH cells. Together, these data indicate that octreotide interacts with high affinity somatostatin receptors to modulate signal transduction and regulate proliferation in neuroblastoma cell lines. These data also suggest that somatostatin receptor expression may be an independent prognostic factor in primary neuroblastoma tumors.

Intraperitoneal 5-fluoro-2'-deoxyuridine with escalating doses of leucovorin: pharmacology and clinical tolerance

In a preceding study, we established the tolerance and pharmacokinetic behavior of 5-fluoro-2'-deoxyuridine (FdUrd) given by the intraperitoneal (IP) route. A dose of 3 g daily x 3 days was found satisfactory for Phase II study and exploration of biochemical modulation. Therefore, the current study was conducted to study the tolerance and pharmacokinetics of such a dose-schedule and route of FdUrd combined with escalating doses of leucovorin (LV). Fourteen patients were entered and 13 were evaluable for tolerance determination. Pharmacologic determinations of IP FdUrd and 5-Fluorouracil (FUra) derived from it and LV were obtained by HPLC methods on 11 occasions. Findings were compared with the preceding study of FdUrd alone. LV did not appear to alter the tolerance of IP FdUrd even in the four patients receiving the highest dose of LV (640 mg). Toxicities included nausea, vomiting, and rarely neutropenia and diarrhea. Pharmacokinetic parameters indicate a parallel rate of egress of FdUrd and LV from the peritoneal cavity. The pharmacologic advantage for FdUrd is at least 3 logs as previously reported and one log for LV. Evidence of antitumor effect was noted particularly among untreated patients with gastrointestinal primaries. We conclude that IP FdUrd 3 g and LV in doses of up to 640 mg x 3 days are well tolerated. Since FdUrd is more potent, has an even greater hepatic clearance and shows greater potential for modulation with LV than FUra, it may be the preferred fluoropyrimidine for subsequent studies via the IP route in the treatment of carcinomas with prominent peritoneal spread. The pharmacologic advantage for leucovorin is limited but it is a good marker for peritoneal clearance since it parallels FdUrd clearance.

Finger cooling by contact with cold aluminium surfaces--effects of pressure, mass and whole body thermal balance

Finger skin temperature change during contact with a cold aluminium surface was studied in 20 subjects (10 men and 10 women). Contact pressure (0.1 N, 5.9 N and 9.8 N), contact material mass (large one, mass 3559 g, small one, mass 108 g), surface temperatures (-7 degrees C, 0 degree C, +7 degrees C) and whole body thermal balance were controlled as independent factors. The contact experiments were performed in a small chamber and only the first section of the index finger of the left hand was in contact with the aluminium surface. The results indicated that all the factors studied had significant effects on the contact skin temperature change with time. The study confirmed that a modified Newtonian model with two components can accurately describe the contact skin temperature change with time. The study resulted in three predictive models for critical skin temperature when in contact with cold aluminium. The results indicated that metal surfaces in contact with bare hands should not be below 4 degrees C surface temperature. Lower temperatures require insulating material or the wearing of protective gloves.

Neurofibromatosis 1 mRNA expression in blood vessels

Vascular hypertrophic lesions occur in neurofibromatosis type 1 (NF1). The role of the gene which causes NF1 in the growth and development of blood vessels is not known. mRNA expression of the NF1 gene was studied in blood vessels in the transition between intact and culture and in quiescent and proliferative conditions. The expression and alternative splicing pattern of the catalytic domain of NF1 consistently changed in proliferating cells, supporting a role for this gene in the regulation of growth of vascular smooth muscle and the vascular pathology in NF1.

Quantitative trait locus effects and environmental interaction in a sample of North American barley germ plasm

Quantitative trait locus (QTL) and QTL x environment (E) interaction effects for agronomic and malting quality traits were measured using a 123-point linkage map and multi-environment phenotype data from an F1-derived doubled haploid population of barley (Hordeum vulgare). The QTL × E interactions were due to differences in magnitude of QTL effects. Highly significant QTL effects were found for all traits at multiple sites in the genome. Yield QTL peaks and support intervals often coincided with plant height and lodging QTL peaks and support intervals. QTL were detected in the vicinity of a previously mapped Mendelian maturity locus and known function probes forα- andβ-amylase genes. The average map density (9.6 cM) should be adequate for molecular marker-assisted selection, particularly since there were few cases of alternative favorable alleles for different traits mapping to the same or adjacent intervals.

Identification of two mPPAR related receptors and evidence for the existence of five subfamily members

Two additional forms of mouse peroxisome proliferator activated receptor have been identified from cDNA libraries derived from mouse tissues using a low stringency cross-hybridization screening method. One is mNUCI, which has 97% amino acid sequence identity with hNUCI in its DNA binding domain. The other one is mPPAR gamma. The full-length cDNA of mPPAR gamma encodes a protein of 470 amino acids in length. The overall amino acid sequence identity is 75% as compared with xPPAR gamma, with the highest homology in the DNA binding region and ligand binding region, 97% and 86% identity, respectively. The discovery of two new forms of mPPAR and the recent cloning of hPPAR provide evidence for the existence of at least five different forms of receptor in the peroxisome proliferator activated receptor subfamily.

Characterization of a cloned human dihydrotestosterone/androstanediol UDP-glucuronosyltransferase and its comparison to other steroid isoforms

A human cDNA, UDPGTh-3, encoding a dihydrotestosterone/5 alpha-androstane-3 alpha,17 beta-diol UDP- glucuronosyltransferase (transferase) has been isolated and characterized. The nucleotide sequence of UDPGTh-3 encodes a 530 amino acid protein with a typical membrane insertion-signal peptide, a membrane-anchoring domain, and three potential asparagine-linked glycosylation sites. Alignment shows that this encoded isozyme is 96% identical to an apparent estriol-metabolizing isoform, HLUG4 [Coffman, B. L., et al., (1990) Arch. Biochem. Biophys. 281, 170-175]. The udpgth-3 isozyme is 78% identical to two other steroid isoforms, HLUG25 (udpgth-1) [Jackson, M. R., et al. (1987) Biochem. J. 242, 581-588; Ritter, J. K., et. al. (1992) Biochemistry 31, 3409-3414] and udpgth-2 [Ritter, J. K., et al. (1990) J. Biol. Chem. 265, 7900-7906]. udpgth-2 and udpgth-1 metabolized parallel substrates (stereospecific estriols, 3,4-catechol estrogens, and the bile salt hyodeoxycholate), except that udpgth-2 was 100-fold more effective than udpgth-1. The mRNA encoding udpgth-3 is 2.4 kb in size and is present in liver, prostate, and testis; the mRNA encoding udpgth-2 is located in liver and kidney, whereas that for udpgth-1 is liver-specific. Each of the liver mRNA species encoding udpgth-3, udpgth-2, or udpgth-1 was induced 2.5-3-fold by phenobarbital treatment of the Erythrocebus patas monkey. In 16 human liver mRNA samples, the message encoding udpgth-3 was generally uniformly expressed and that for udpgth-1 exhibited wide variations in its level, whereas that for udpgth-2 was barely detectable in nine samples and not detectable in the others. Three samples contained no message for either isoform. Substrate turnover by udpgth-3 is ranked as follows: phenolphthalein > 5 alpha-androstane-3 alpha,17 beta-diol > 5 alpha- dihydrotestosterone = 4-hydroxybiphenyl > phenolsulfonphthalein (phenol red) > phenolphthalin. Genes encoding udpgth-3, udpgth-2, and udpgth-1 mapped to human chromosome 4 with genomic DNA from human/mouse and human/hamster somatic cell hybrids; the genes encoding udpgth-1 and udpgth-2 mapped specifically to band 4q28. udpgth-3 exhibited similar Km values both for 5 alpha-dihydrotestosterone (10 microM) and for its metabolite, 5 alpha-androstane-3 alpha,-17 beta-diol (12.5 microM).(ABSTRACT TRUNCATED AT 400 WORDS)

[Line width addition method and its application to biologic materials emission spectrum analysis]

Using alternating current are grating spectrograph, and self-made recording microphotometer for line contour and accurate measurement of line width, we measured the concentration of Cu and Ca in serum-like synthetic standard solution with line width addition method. The experimental results had better linearity, reproducibility and higher precision compared with those by density method, suggesting that line width method is better than density method in the analysis of biologic material concentration.

Carcinoma of the thyroglossal duct: case reports and a literature review

Carcinoma of the thyroglossal tract is a rare entity. Three patients with thyroglossal cyst carcinomas are presented and the features of the disease, as reported in the literature, are discussed. Epidemiologically, females are more often affected than males and the average age of the patients described lies in the fourth decade. The aetiology is obscure, although previous irradiation is a possible risk factor. Carcinoma of the thyroglossal tract should also be suspected in patients with irregular masses. Pre-operative evaluation may include a thyroid scan and fine needle aspiration cytological examination of the cyst fluid. These tests, if positive, may alter the basic approach of the Sistrunk procedure to encompass thyroidectomy or wider margins. Neck dissection is preferred for cervical nodal disease. Adjuvant radiotherapy or radio-iodine is added if indicated by the histology, and the patient receives suppressive thyroxine therapy thereafter.

Hybrid enzymes for structure-function analysis of cytochrome P-450 2B11

Previous work has shown that P-450 2B11 is responsible for the unique ability of dogs to metabolize and eliminate certain highly-chlorinated biphenyls such as 2,2',4,4',5,5'-hexachlorobiphenyl (245-HCB), whereas the related P-450 2B forms in rat and rabbit are unable to metabolize the compound to any significant degree. To determine the structural basis for this functional diversity, hybrid enzymes were generated. Success with this approach required a careful choice of second enzyme and common substrate with which to assess the functional integrity of the hybrid proteins. The choices of P-450 2B5 from rabbit as the second enzyme and androstenedione as the substrate were based in part on the finding that P-450 2B11 and P-450 2B5 hydroxylate androstenedione with similar overall activities but distinct profiles. Enzymatic studies with eight hybrid enzymes provided evidence for two regions of P-450 2B11 and 2B5, between residues 95-239 and 240-370, that appear to be involved in defining substrate specificity for androstenedione, and three regions of P-450 2B11, between residues 95-239, 240-370, and 371-494, that contain amino acids necessary for metabolism of 245-HCB. This deliberate approach to the creation of hybrid cytochromes P-450 has generated a series of enzymes that will be central to further structure-function studies of the cytochromes P-450 2B.

[Quality control of radiopharmaceuticals from the clinical aspect--a necessity?]

Radiopharmaceuticals are a special group of drugs since many are eventually prepared in the hospital and the nuclear medicine department is responsible for meeting quality criteria such as sterility, radionuclide, radiochemical and chemical purity of these drugs. We tested 266 preparations of 14 different radiopharmaceuticals from commercial kits for their radiochemical purity. Only four compounds showed deficiencies in labelling (anti-granulocyte MAb, HIG, HMPAO, MAG3, altogether 18 preparations). All of them were 99mTc-pharmaceuticals with a relatively low tin content of the kit. The reasons for the poor quality of these products could be found. This study shows the importance of a good quality control system (including other tests like sterility and environmental monitoring) to guarantee the safety and efficacy of radiopharmaceuticals prepared in the hospital.