Sonographic measurement of renal transplant area compared with scintigraphy

A change in transplant size, which can easily be measured by ultrasound, is one indicator of acute or chronic rejection. We report here on 49 areal measurements of transplant size from a coronal section and compare the results with isotopically measured areas. The areas measured in the isotope examinations correlated well with those measured sonographically (r = 0.82) in the case of the 33 transplants with a normal perfusion index but poorly (r = 0.45) in those with an abnormal perfusion index. The sonographically measured transplant area was about 85 cm2 in cases of acute rejection, 54 cm2 in cases of chronic rejection and 62 cm2 in cases with normal or slightly impaired transplant function (creatinine level below 200 mumol). Sonography is more suitable than isotope examination for monitoring transplant size in cases with poor perfusion.     

Biological monitoring of occupational exposure to low levels of benzene.

To obtain reference values for the biological monitoring of benzene, the kinetics of benzene were studied in volunteers. Benzene in blood and expired air could easily be followed until the next morning after a 4-h exposure to a benzene concentration of 10 cm3.m-3. Even after exposure to 1.7 cm3.m-3 the benzene levels in the morning blood and expired air samples differed from those in unexposed subjects. One hour after exposure to 10 and 1.7 cm3.m-3 the mean levels of benzene were 238 and 25 nmol.l-1 in blood and 13.2 and 2.5 mumol.m-3 in exhaled air, respectively. It was concluded that, at high benzene levels (approximately 10 cm3.m-3), samples collected 16 h after exposure reflect the body burden of benzene, while at low exposure (< 1 cm3.m-3) samples collected 1 h after exposure may be used to estimate the exposure over the preceding few hours. Exposure to benzene from smoking is a potential confounder in estimating occupational exposure to low levels of benzene.     

Fixation of femoral shaft osteotomy with an intramedullary composite rod: an experimental study on dogs with a two-year follow-up

A novel composite material with an ultra-high strength and a low elastic modulus called carbon fibre-reinforced liquid crystalline polymer (LCP/CF) has been developed. An experimental diaphyseal osteotomy of the proximal femur in fourteen Beagle dogs was fixed with an intramedullary LCP/CF rod of 4.5 mm in diameter and 80 mm in length. The radiological follow-up intervals were 1, 3, 6, 12, 24, 52, and 104 weeks. Five dogs were killed at 1 year and three dogs at 2 years for histological studies; six dogs were retained for longer follow-up. Radiographs showed an uncomplicated healing of the diaphyseal osteotomy with an external callus formation in all dogs in 12 weeks. Histological analysis revealed a benign host tissue response with few inflammatory cells. Both bone and fibrous tissue were seen at the LCP/CF-host tissue interface. The cross-sectional cortical area of the operated femur was slightly greater than that of the control femur in the 2-year follow-up. LCP/CF showed promising properties for high-load applications.     

Hevein-specific recombinant IgE antibodies from human single-chain antibody phage display libraries

IgE antibodies distinctively recognising allergenic epitopes would be ideal reagents in immunodiagnostics to detect and quantify allergens, as well as for the development of allergy diagnostics and therapeutics. We have isolated recombinant human IgE antibodies specific for the major latex allergen, hevein, from antibody phage display libraries using a green fluorescent protein (GFP)-hevein fusion as a selection antigen. Human IgE phage display libraries were constructed by combining the IgE heavy chain genes to kappa and lambda light-chain genes which were isolated from lymphocytes of a latex allergic patient. The screening of antibody libraries resulted in the enrichment of two hevein-binding scFvs designated as 1A4 and 1C2. Both antibodies showed specific binding to the hevein that could be inhibited by both the recombinant GFP-hevein and native hevein isolated from latex examination gloves. The scFvs were prone to aggregate and, thus, for further characterisation, they were converted to Fab fragments with human IgG1 or IgE isotype. Similar hevein-binding properties of the 1A4 and 1C2 Fab fragments and human IgE serum pool, conventionally used in the detection of latex allergens, demonstrate the potential utility of these recombinant antibodies for the analysis of latex allergen.     

A transient acidification linked to intracellular Ca2+ in anti-mu-stimulated human B-lymphocytes.

Mitogen-induced cellular proliferation is in many cell types preceded by rapid changes in intracellular pH and free Ca2+ concentration. We studied the patterns of pH and Ca2+ changes in normal resting human B-lymphocytes after exposure to anti-mu antibodies and the monoclonal antibody IF5, reactive with the CD20 antigen, both able to activate resting B-lymphocytes to enter the G1 phase of the cell cycle. Monitoring intracellular pH with the pH-sensitive, fluorescent dye, 2',7'-bis(carboxyethyl)-5,6-carboxy-fluorescein, we demonstrated that poly- and monoclonal anti-mu antibodies induced a rapid (maximum change within 2 min) intracellular acidification of 0.06 pH units followed by a slower (10-15 min) alkalinization towards, or slightly above, the resting pH of 6.88. The acidification response was amiloride-resistant, whereas the return to baseline was sensitive. Intracellular free Ca2+ was measured by using the fluorescent Ca2+ dye, indo-I. Exposure of cells to anti-mu resulted in a rapid increase (maximum change within 2 min) in cytoplasmic Ca2+ of 340 nM and a slower decline in fluorescence back to baseline of about 180 nM. In contrast to anti-mu, IF5 caused no change in cytoplasmic Ca2+ and pH. However, the Ca2+ ionophore ionomycin at low concentrations mimicked the Ca2+ response as well as the pH response to anti-mu. In Ca2(+)-free solutions the intracellular Ca2+ stores are usually rapidly depleted and, indeed, the Ca2+ and pH responses to anti-mu were reduced after 5 min and almost abolished after 35 min under such conditions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Detection of a novel repeated sequence useful for epidemiological typing of pathogenic Yersinia enterocolitica

Strains (n = 203) of Yersinia species were used in genotyping and PCR experiments in order to evaluate the genotyping potential of the YeO:3RS probe. This probe comprises a 12.5 kb genomic fragment of the Y. enterocolitica O:3 lipopolysaccharide O-antigen gene cluster cloned into plasmid pBR322. The genotyping potential of YeO:3RS was shown to reside in the region upstream of the O-antigen gene cluster, i.e., in the first 1.65 kb of the cloned genomic fragment that contains a repeated sequence (RS) present in multiple copies in the genome. In genotyping, the YeO:3RS probe was hybridised to DNA of Yersinia enterocolitica isolates (n = 112) from humans, animals and food, along with strains of other Yersinia species (n = 5) and Salmonella enterica strains (n = 3). The YeO:3RS probe efficiently detected and subtyped all European pathogenic Yersinia enterocolitica isolates of the serobiotypes O:3/4, O:9/2 and O:5,27/2 studied (n = 87), whereas it hybridised only weakly or not at all with the other strains. Within Yersinia enterocolitica serobiotype O:3/4 strains, YeO:3RS genotyping was as discriminatory as genotyping by pulsed-field gel electrophoresis (PFGE) of XbaI-NotI digested genomic DNA. When these two methods were combined, YeO:3RS genotyping divided both of the two predominant PFGE types into six subtypes, thus increasing the discrimination. In PCR screening of additional 86 Yersinia strains, the 1.65 kb region was detected in European pathogenic serotypes O:1 and O:2 in addition to serotypes O:3, O:5,27 and O:9, indicating that it can be exploited in detecting and typing of European pathogenic serotypes in general.     

Dopamine transporters increase in human brain after alcohol withdrawal

Dopaminergic transmission has been suggested to be a main mechanism mediating reinforcement, withdrawal and craving associated with alcohol addiction. We measured here striatal dopamine (DA) transporter binding from 27 alcoholics within 4 days after cessation of prolonged heavy drinking and after a 4-week period of abstinence with single photon emission computed tomography (SPECT) using a cocaine analogue, iodine-123-beta-CIT. Controls were 29 healthy volunteers. Blind quantitative analyses of the SPECT data revealed markedly lower DA transporter binding in alcoholics on admission for detoxification than in the non-alcoholic controls. After a 4-week period of abstinence DA transporter binding increased significantly in the alcoholics (P<0.0001) reaching the levels of the healthy controls. The most substantial recovery in DA transporter binding occurred during the first 4 days of abstinence. The data indicate that prolonged heavy drinking decreases DA transporter binding and disturbs synaptic dopamine transport. This may sensitize alcoholics to dopaminergic transmission, which may lead to early relapse after ethanol withdrawal.     

Immunohistochemical expression of DNA repair proteins in familial breast cancer differentiate BRCA2-associated tumors.

PURPOSE: Morphologic and immunohistochemical studies of familial breast cancers have identified specific characteristics associated with BRCA1 mutation-associated tumors when compared with BRCA2 and non-BRCA1/2 tumors, but have not identified differences between BRCA2 and non-BRCA1/2 tumors. Because BRCA1 and BRCA2 genes participate in the DNA repair pathway, we have performed an immunohistochemical study with markers related to this pathway to establish the profile of the three groups. MATERIALS AND METHODS: We have studied two tissue microarrays that include 103 familial and 104 sporadic breast tumors, with a panel of DNA repair markers including ATM, CHEK2, RAD51, RAD50, XRCC3, and proliferating cell nuclear antigen. RESULTS: We found more frequent expression of CHEK2 in BRCA1 and BRCA2 tumors than in non-BRCA1/2 and sporadic tumors. We found absence of nuclear expression and presence of cytoplasmic expression of RAD51 in BRCA2 tumors that differentiate them from other familial tumors. We validated these results with a new series of patient cases. The final study with 253 familial patient cases (74 BRCA1, 71 BRCA2, 108 non-BRCA1/2), and 288 sporadic patient cases, has allowed us to confirm our preliminary results. Because BRCA2 tumors present a specific immunohistochemical profile for RAD51 and CHEK2 markers that is different from non-BRCA1/2 tumors, we have built a multivariate model with these markers that distinguish both tumors with an estimated probability of at least 76%. CONCLUSION: Our results suggest that BRCA2 tumors demonstrate more cytoplasmic and less nuclear RAD51 staining, and increased CHEK2 staining. This pattern may distinguish BRCA2 from familial non-BRCA1/2 tumors.