Congenital abnormalities and clinical features associated with Wilms' tumour: a comprehensive study from a centre serving a large population.

Altogether 156 children treated for Wilms' tumour (WT) between 1970 and 1998 were studied. Sixty-six children, selected only by their attendance at clinic, were carefully examined and the findings compared to those from a case note review of 90 children. Congenital abnormalities were present in 45% of the examined cohort, in 19% of the case notes review group and in 30% overall. Novel findings included the association of WT with Marshall Smith syndrome, developmental delay in 3 of 4 cases of WT (one bilateral) and 1 sibling from consanguineous Pakistani families and another sibling also had leukaemia. The possibility of rare DNA repair or cancer predisposing disorders among these 4 families requires further study. Careful examination and history taking of an unselected patient cohort revealed a higher than expected incidence of clinical abnormalities which may be overlooked if not specifically sought.

A large nontypical outbreak of Norwalk virus. Gastroenteritis associated with exposing celery to nonpotable water and with Citrobacter freundii.

The US Air Force Academy experienced a point-source outbreak of gastroenteritis originally believed to be caused by Salmonella. The overall attack rate was 48% among approximately 3000 cadets and staff. Food-specific attack rates implicated chicken salad. The odds ratio for chicken salad consumption in ill cadets was 10.7 (95% confidence interval: 8.2; 13.8). The celery component had been exposed to nonpotable water. Citrobacter freundii were statistically associated with consumption of the suspected vehicle and subsequent illness. Most aspects were consistent with the epidemiology of Norwalk gastroenteritis. However, the clinical presentation was not typical of reported outbreaks. One hundred five cadets required intravenous rehydration. Serum samples implicated Norwalk virus as the most probable cause of this outbreak. The Centers for Disease Control (Atlanta, Ga) recently began national surveillance for viral gastroenteritis. All outbreaks of gastroenteritis associated with nonpotable water should be investigated for evidence of viral cause.

Amniotic fluid gamma-glutamyl transferase activity in trisomy 21 and neural tube defects.

The amniotic fluid gamma-glutamyl transferase (gamma GT) has been measured in normal pregnancies (n = 128), six pregnancies associated with trisomy 21 and 12 pregnancies involving a foetus with a neural tube defect. In normal pregnancies, the amniotic fluid gamma GT activity falls during the second trimester, the level at 20 wk being 60% of that at 14 wk. In the six cases of trisomy 21 and 8 of the 12 cases with neural tube defects, the gamma GT levels were below the 95% confidence limit.

Determination of petroselinic acid by microreactor chromatography.

The microreactor-ozonolysis technique was applied to the quantitative determination of the relative amounts of petroselinic and oleic acids in seven Umbelliferae seed oils. The operation was easy and rapid. Results were excellent when the method was tested on ester mixtures of known composition. When used on esters prepared from Umbelliferae seed oils, the method gave results comparable with those found by another procedure, also described, which combined thin-layer chromatography with either gas-liquid chromatography or ultraviolet spectrophotometry.

Isotope edited internal standard method for quantitative surface-enhanced Raman spectroscopy.

A new isotope edited internal standard (IEIS) method for quantitative surface-enhanced Raman spectroscopy (SERS) is demonstrated using rhodamine 6G (R6G-d0) and rhodamine 6G (R6G-d4) edited with deuterium. The reproducibility and accuracy of the IEIS method is investigated both under optical resonance (SERRS) and nonresonance (SERS) conditions. A batch-to-batch concentration measurement reproducibility of better than 3% is demonstrated over a concentration range of 200 pM-2 microM with up to a factor of 3 difference between the concentration of the analyte and its IEIS. The superior performance of the IEIS method is further illustrated by comparing results obtained using absolute SERS/SERRS intensity calibration (with no internal standard) or using adenine (rather than R6G-d4) as an internal standard for R6G concentration quantization. Potential biomedical gene expression and comparative proteomic applications of the IEIS method are discussed.

Adherence of staphylococcus aureus to influenza A virus-infected Madin-Darby canine kidney cell cultures.

Madin-Darby canine kidney cells infected with influenza A virus (strains PR8, FM1, Jap 305, and Tex 1) were tested with nine strains of Staphylococcus aureus and group B Streptococcus type Ic to determine whether mammalian cells become susceptible to bacterial adherence as a result of virus infection. Bacterial adherence to virus-infected cells varied depending on the virus strain and on the strain of bacteria tested. A quantitative radioassay was developed to study the parameters of adherence. Attachment of 3H-labeled S. aureus grown in chemically defined or biologically complex medium to FM1 virus-infected cells was significantly increased (P less than 0.0005) compared with attachment to control cells. Adherence coincided with the appearance of hemadsorption, which is a marker of the presence of virus-induced glycoproteins on the cell surface. Adherence was temperature dependent, increased with a decrease in hydrogen ion concentration, and was not affected by the presence of K+, Mg2+, or Ca2+. Adherence was blocked when 3H-labeled S. aureus was pretreated with trypsin but not when cells were pretreated with neuraminidase.

Factors influencing adherence of Staphylococcus aureus to influenza A virus-infected cell cultures.

A quantitative radioassay was used to study the factors affecting the adherence of (3)H-labeled Staphylococcus aureus 1071 to Madin-Darby canine kidney cells, either uninfected or infected with the human FM1 strain of influenza A virus. Enhanced adherence to virus-infected cell cultures was independent of nonspecific factors-hydrophobicity, surface charge, and monolayer cell density. Viral hemagglutinin and neuraminidase did not act as the cell receptors for S. aureus because the growth of virus-inoculated monolayers in tunicamycin (an inhibitor of glycosylation) and the pretreatment of virus-infected cells with trypsin or virus-specific antiserum, which inhibit hemadsorption, had no effect on staphylococcal adherence. In contrast, adherence to uninfected and virus-infected cells was significantly reduced by protease treatment of either monolayers or staphylococci and by heat treatment of staphylococci. UV irradiation and treatment of bacteria with 0.1 M EDTA enhanced adherence. Pretreatment of monolayers with a thermal extract of S. aureus decreased adherence by 89 to 97%. The staphylococcal adhesin, which blocks adherence to virus-infected cells, appears to be a remarkably heat-stable, protease- and trypsin-sensitive macromolecule which is distinct from protein A, clumping factor, and teichoic acid. Lastly, pretreatment of S. aureus with human fibrinogen significantly enhanced adherence to virus-infected cells (P < 0.005) compared with binding with untreated S. aureus. The treated bacteria also adsorbed virus out of suspension. These results suggest that fibrinogen forms a bridge between S. aureus and receptors present on virus-infected cells and free virus.

Microreactor for methanolysis of triglycerides before gas-liquid chromatography.

A rapid, accurate microtechnique has been developed for gas chromatographic determination of the fatty acid composition of small (2-3 micro l) samples of vegetable oils. This microtechnique combines transesterification and sample injection into a single operation. The fatty acid compositions of soybean, linseed, and safflower oils thus determined are compared with those obtained by the usual two-step procedure.

Staphylococcus aureus adherence to influenza A virus-infected and control cell cultures: evidence for multiple adhesins.

During major epidemics with influenza, there is an increased number of pneumonias due to Staphylococcus aureus with a subsequent high mortality rate. We have postulated that influenza A virus infection of host cells promotes the adherence of S. aureus ultimately resulting in bacterial superinfection. In the present study we compared the adherence of seven strains of 3H-labeled S. aureus to Madin-Darby canine kidney (MDCK) cell monolayers, uninfected and infected with influenza A/FM/1/47 virus. Test strains included: Cowan I; a Cowan I protein A-deficient mutant (PA-); EMS, a protein A and clumping factor-deficient mutant; HSmR; 52A5, a teichoic acid-deficient mutant of HSmR; M, an encapsulated strain; and, No. 1071, a clinical isolate. By radioassay, six of the seven strains demonstrated significantly enhanced adherence to virus-infected cell monolayers compared to uninfected controls; only the M strain was adherence negative. Surface hydrophobicity of the staphylococci did not correlate with their ability to adhere. Four strains of labeled staphylococci (Cowan I, PA-, EMS, and No. 1071), untreated or treated with 2.5% trypsin, 1.25% protease, or by autoclaving, were tested in the radioassay. Protease treatment, which was more effective than trypsin treatment, reduced adherence of all four test strains by 74-96%. Results of heat treatment suggested the presence of both thermolabile and thermostable adhesins. Staphylococcal thermal extracts, profiled by anion-exchange HPLC, were used to pretreat monolayers in a blocking radioassay. Adherence was decreased to control cells (9-78%) and to virus-infected cells (56-90%). The data suggest that multiple distinct surface proteins mediate the binding of S. aureus to uninfected and influenza A virus-infected cells.

Fibrinogen-mediated adherence of group A Streptococcus to influenza A virus-infected cell cultures.

A quantitative radioassay was used to study the adherence of group A Streptococcus to Madin-Darby canine kidney cells infected with influenza A virus (strains FM1, Jap 305, and NWS) and reacted with fibrinogen. Treatment of virus-infected cell cultures with human fibrinogen significantly enhanced streptococcal adherence (P less than 0.0005) compared with adherence to untreated, virus-infected cells and uninfected control cells. Enhanced adherence was not seen with NWS virus-infected cell cultures or with virus-infected cells treated with human fibronectin, canine fibrinogen, or porcine fibrinogen. Human fibrinogen was shown to bind directly to surface membranes of virus-infected cells. Virus-infected cell cultures were incubated in the presence of tunicamycin, an antibiotic that inhibits glycosylation of virus-specific surface membrane glycoproteins. We found that with increasing antibiotic concentration there was a progressive decrease in fibrinogen-mediated streptococcal adherence. Adherence of 3H-labeled streptococci to fibrinogen-treated, virus-infected cell cultures showed saturation kinetics and could be blocked with monospecific antibodies against fibrinogen. These results suggest that human fibrinogen binds to a glycoprotein moiety on the surface of influenza A virus-infected cells, and that once bound the fibrinogen molecule acts as an "acquired" receptor for the attachment of group A Streptococcus. We postulate that this mechanism, it if occurs in vivo, might help explain the observed association between influenza A virus infection and subsequent bacterial superinfection with group A Streptococcus.

Amniotic fluid acetylcholinesterase activity and alpha-fetoprotein in chromosomal anomalies and neural tube defects.

Measurement of alpha-fetoprotein concentration and acetylcholinesterase activity in amniotic fluid can be used to identify chromosomal defects as well as neural tube defects. In seven cases of trisomy 21 and one case of partial trisomy 3, alpha-fetoprotein concentrations were below the reference range but values for acetylcholinesterase activity were normal for the appropriate gestational age. One case of trisomy 13 had an increase in acetylcholinesterase activity and normal alpha-fetoprotein concentration.

Duplication of chromosome 2 in association with ventriculomegaly - a case report.

This is a case report of the prenatal diagnosis of a de novo interstitial duplication of chromosome 2 (46,XX,dup(2)(p13p21) de novo) with an associated phenotypic abnormality. This chromosomal duplication is rare, only one has previously been described prenatally. Postnatal reports of similar duplications in this region have described associated dysmorphic features and significant neurodevelopmental delay. In our case, the only ultrasound finding was moderately severe ventriculomegaly. At post-mortem, ventriculomegaly was confirmed and there was associated macrocephaly (head circumference above the 97th centile) with no dysmorphic features seen.

Confirmation of FWT1 as a Wilms' tumour susceptibility gene and phenotypic characteristics of Wilms' tumour attributable to FWT1.

A susceptibility gene for Wilms' tumour (WT), designated FWT1, was previously mapped to chromosome 17q12-q21 by linkage analysis of a single family. We now confirm the existence of this gene by analysis of additional cases in the original family (3-point LOD score=5.69), and by detecting strong evidence of linkage to this region in an unrelated pedigree with seven cases of WT (3-point LOD score=2.56). Analysis of 11 smaller WT families confirms that there is genetic heterogeneity in familial WT, as three families exhibit strong evidence against linkage to FWT1. One of these was subsequently found to have a predisposing WT1 mutation. However, the other two families show evidence against both FWT1 and WT1, suggesting that at least one further familial WT gene exists. Analysis of the phenotype of 16 WT cases from the families linked to FWT1 demonstrates that they present at a significantly older age and a significantly later stage than both sporadic WT and the six cases from two families unlinked to either FWT1 or WT1. The results confirm the role of FWT1 in susceptibility to WT, provide strong evidence for genetic heterogeneity in familial WT and suggest there are phenotypic differences between familial WT due to FWT1, familial WT due to other genes and non-familial WT.