Analytical techniques for cell fractions. XXIII. A stable thermal gradient device for heat denaturation studies on proteins

The ISO-DALT two-dimensional electrophoretic system (1,2), based on the method of O'Farrell (3), is capable of performing large numbers of analysis on complex mixtures of proteins. However, both separations employed are carried out under dissociating or denaturing conditions and no enzyme activities are readily observable in the analyzed proteins. In order to identify the spots corresponding to particular enzymes, it is therefore necessary to employ some nondestructive resolving technique first and as a second step to perform both enzyme and two-dimensional electrophoretic analyses on the fractions generated. By correlating enzyme activity with intensity of various spots on the two-dimensional gels throughout the series of initial fractions, identifications, can be made. This approach, unlike the more direct immunoprecipitation methods (4), requires the running of large numbers of enzyme analyses and two-dimensional gels and some convenient initial resolving procedure. Convenient and rapid techniques for the analyses (5,6) and gels (1,2) have been described previously in this series and elsewhere. This paper deals with the use of selective denaturation in a temperature gradient as an initial resolving procedure and describes a simple thermal gradient device for generating such a gradient.     

Further evidence for elevated human minisatellite mutation rate in Belarus eight years after the Chernobyl accident

Analysis of germline mutation rate at human minisatellites among children born in areas of the Mogilev district of Belarus heavily polluted after the Chernobyl accident has been extended, both by recruiting more families from the affected region and by using five additional minisatellite probes, including multi-locus probe 33.6 and four hypervariable single-locus probes. These additional data confirmed a twofold higher mutation rate in exposed families compared with non-irradiated families from the United Kingdom. An elevated rate was seen at all three independent sets of minisatellites (detected separately by multi-locus probes 33.15, 33.6 and six single-locus probes), indicating a generalised increase in minisatellite germline mutation rate in the Belarus families. Within the Belarus cohort, mutation rate was significantly greater in families with higher parental radiation dose estimated for chronic external and internal exposure to caesium-137, consistent with radiation induction of germline mutation. The spectra of mutation seen in the unexposed and exposed families were indistinguishable, suggesting that increased mutation observed over multiple loci arises indirectly by some mechanism that enhances spontaneous minisatellite mutation.     

Adolescent female craniofacial morphology associated with advanced bilateral TMJ disc displacement

The aim of this study was to determine if cephalometric measurement differences occurred between two groups of similarly aged female adolescents which differed with respect to their diagnoses of temporomandibular joint disc position on magnetic resonance images (MRI). One group consisted of 17 female adolescents exhibiting complete bilateral disc displacement affecting the temporomandibular joints (TMJ), while the second group of 17 female adolescents was diagnosed as having bilateral normal disc position on MRI. Independent sample t-tests identified statistically significant differences in cephalometric measurements between the two groups, but no age difference between the two groups was evident. The group with bilateral total disc displacement exhibited the following significant angular differences from the group with normal disc position: an increased mandibular and palatal plane relative to sella-nasion; posterior rotation of the mandible as illustrated by an increased angle between the posterior border of the mandibular ramus and sella-nasion; and a decrease in Rickett's facial axis. Significant differences in linear cephalometric variables were also evident between the two groups. Total posterior facial height and ramus height were reduced in the totally disc displaced group. Furthermore, a slight increase in the middle anterior facial height was noted, with a decrease in the posterior cranial base vertical height in the totally disc displaced group.     

Enzymatic activity and expression of cytochrome P450 LA omega within intrasplenically transplanted fetal hepatocytes in spontaneously hypertensive rats

We examined the expression and enzymatic activity of cytochrome P450 LA omega within transplanted hepatocytes. Fetal hepatocytes were harvested at day 20 of gestation from spontaneously hypertensive rats (SHRs) and transplanted into recipient adult SHR spleens. Microscopic examination of the recipient spleens at 4 and 10 wk after transplantation revealed masses of hepatocytes with cord-like structures in the red pulp. Immunochemical studies detected cytochrome (cyto) P450 LA omega in the fetal hepatocytes before transplantation without prior induction. Although the cyto P450 LA omega was not detected by the second week after transplantation, by the 6th and 10th wk after transplantation, it was. Cyto P450-arachidonic acid omega/omega-1 hydroxylase activity (formation of 20- and 19-hydroxyeicosatetraenoic acid) was detected at 10 wk after transplantation, but not 2 or 6 wk after transplantation. These results demonstrated that fetal hepatocytes can be transplanted successfully into recipient spleens and then grow in the spleens, as in the case of the adult hepatocyte response.     

Small cell undifferentiated carcinoma of the pancreas

Small cell undifferentiated carcinoma of the pancreas is a rare neoplasm: Only 12 cases have previously been documented. This paper describes the clinical evolution, immunohistochemical profile, and ultrastructural features of a case occurring in a 37-year-old woman.     

Effect of hydroxylamine hydrochloride on the bacterium Shigella dysenteriae 1 and antigens isolated from them

A study was made into the functional status of hypophysis, adrenal cortex, ovaries, and thyroid gland in patients with kraurosis and leukoplakia vulvae. The above patients demonstrated profound disturbances in the system hypophysis-ovaries, that attest to the need for applying corrective therapies to treat the disturbed hormonal homeostasis.     

Pathogenic micro-organisms in slaughterhouse sludge--a survey

During slaughtering of animals and subsequent meat processing the process water used becomes polluted with organic matter of animal origin (i.e. protein and fat). This organic sludge is, in principle, a product suitable for animal feeding. To investigate the microbiological contamination level of sludge, raw sludge was collected at pig (n = 8) and poultry (n = 5) slaughterhouses. Both flocculated and aerobically activated sludge was monitored. Slaughterhouse sludge was heavily contaminated with Enterobacteriaceae (6.3-10.0 in log10 N/gram dry matter) and enterococci (4.6-7.9). Clostridia were present in sludge at a level of 3.1-5.8 (in log10 N/g DM). Salmonella was present in the sludge from all slaughterhouses examined. Yersinia enterocolitica serotypes O:3 and O:9 were found in sludge from seven out of thirteen slaughterhouses. The prevalence of Campylobacter jejuni/coli was higher in flocculated poultry sludge than in both flocculated pig sludge and aerobically activated pig sludge. Obviously, decontamination of the sludge is mandatory when it is to be applied as a feed constituent, to prevent bacterial cycles from occurring in livestock, as well as the spread of human pathogenic zoonoses like campylobacter, salmonella and yersinia, to minimize loss of protein quality by the microbial breakdown of amino acids and the formation of possible toxic metabolites in sludge during storage.     

Refined chromosomal localization of the mismatch repair and hereditary nonpolyposis colorectal cancer genes hMSH2 and hMSH6

The genomic loci for the mismatch repair genes hMSH2 and hMSH6 were mapped by fluorescence in situ hybridization, analysis of radiation hybrid panel markers, and linkage analysis of syntenic chromosome regions between human and mouse. Both genes were localized to chromosome 2p21, adjacent to the luteinizing hormone/choriogonadotropin receptor gene (LHCGR; 2p21), telomeric to the D2S123 polymorphic marker, and centromeric to the calmodulin-2 gene (CALM-2; 2p22-21) and son-of-sevenless gene (SOS; 2p22-21). The genomic locations of hMSH2 and hMSH6 appears to be within 1 Mb of each other because they could not be separated by interphase fluorescence in situ hybridization. These results clarify the position of the chromosome 2 hereditary nonpolyposis colorectal cancer locus, which was originally reported to be associated with an adjacent region (chromosome 2p14-16).