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Maternal immunization is an important strategy to prevent severe morbidity and mortality in mothers and their offspring. This study aimed to identify whether new parents were following immunization recommendations prior to pregnancy, during pregnancy, and postnatally. A cross-sectional survey was conducted by a questionnaire administered antenatally to pregnant women attending a maternity hospital with a follow-up telephone interview at 8-10 weeks post-delivery. Factors associated with uptake of pertussis vaccination within the previous 5 y or postnatally and influenza vaccination during pregnancy were explored using log binomial regression models. A total of 297 pregnant women completed the questionnaire. For influenza vaccine, 20.3% were immunized during pregnancy and 3.0% postnatally. For pertussis vaccine, 13.1% were vaccinated within 5 y prior to pregnancy and 31 women received the vaccine postnatally, 16 (51.6%) received the vaccine >4 weeks after delivery. Receiving a recommendation from a healthcare provider (HCP) was an independent predictor for receipt of both pertussis (RR 2.07, p < 0.001) and influenza vaccine (RR 2.26, p = 0.001). Non-English speaking mothers were significantly less likely to have received pertussis vaccination prior to pregnancy or postnatally (RR 0.24, p = 0.011). Multiparous pregnant women were less likely to have received an influenza vaccine during their current pregnancy (p = 0.015). Uptake of pregnancy related immunization is low and likely due to poor knowledge of availability, language barriers and lack of recommendations from HCPs. Strategies to improve maternal vaccine uptake should include education about recommended vaccines for both HCPs and parents and written information in a variety of languages.

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The FixL/FixJ two-component regulatory system of Sinorhizobium meliloti controls the expression of nitrogen fixation genes in response to O2. When phosphorylated, the transcription factor FixJ binds to the nifA and fixK promoters in S. meliloti and induces expression of the corresponding genes, both of which encode key transcription activators. Phosphorylation of FixJ has been proposed to occur via the following cascade. The sensor kinase FixL reacts with ATP independently of FixJ, transferring a phosphoryl group to one of its own histidine residues. Dissociation of O2 from a heme-binding PAS domain in FixL greatly accelerates the rate of this autophosphorylation. The phosphoryl group is rapidly transferred from phospho-FixL to an aspartate residue on FixJ. The resulting phospho-FixJ is short-lived, due to a FixL-catalyzed hydrolysis of the aspartyl phosphate. Here, we show that phosphorylation of FixLJ, i.e. the complex of FixL with FixJ, is at least tenfold faster than the phosphorylation of FixL without FixJ. We further show that a phospho-FixJ phosphatase, thought to reside in FixL, is absent from this complex. These results indicate that FixLJ reacts with ATP as a unit and much more efficiently than FixL alone, and that autophosphorylation and phosphoryl transfer do not occur independently, in sequence, but rather in a closely coupled processive reaction. These findings highlight the possible influence of synergistic interactions of the regulatory components in two-component-system signal transduction.

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The phosphodiesterase A1 protein of Acetobacter xylinum, AxPDEA1, is a key regulator of bacterial cellulose synthesis. This phosphodiesterase linearizes cyclic bis(3'-->5')diguanylic acid, an allosteric activator of the bacterial cellulose synthase, to the ineffectual pGpG. Here we show that AxPDEA1 contains heme and is regulated by reversible binding of O(2) to the heme. Apo-AxPDEA1 has less than 2% of the phosphodiesterase activity of holo-AxPDEA1, and reconstitution with hemin restores full activity. O(2) regulation is due to deoxyheme being a better activator than oxyheme. AxPDEA1 is homologous to the Escherichia coli direct oxygen sensor protein, EcDos, over its entire length and is homologous to the FixL histidine kinases over only a heme-binding PAS domain. The properties of the heme-binding domain of AxPDEA1 are significantly different from those of other O(2)-responsive heme-based sensors. The rate of AxPDEA1 autoxidation (half-life > 12 h) is the slowest observed so far for this type of heme protein fold. The O(2) affinity of AxPDEA1 (K(d) approximately 10 microM) is comparable to that of EcDos, but the rate constants for O(2) association (k(on) = 6.6 microM(-)(1) s(-)(1)) and dissociation (k(off) = 77 s(-)(1)) are 2000 times higher. Our results illustrate the versatility of signal transduction mechanisms for the heme-PAS class of O(2) sensors and provide the first example of O(2) regulation of a second messenger.

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Test turnaround times are often monitored on a monthly basis. However, such an interval usually means that not all causes for delay in test reporting can be unequivocally identified for institution of remedial action. We have devised a daily chart--the freckle plot--that graphically displays the test turnaround times by laboratory receipt time. Different symbols are used to designate specimens reported within the test's turnaround time limit, those within 10 min beyond that limit, and those well outside the limit. These categories are adjustable to suit different limits of stringency. Freckle plots are produced on a daily basis and can be used to track down causes for test delays. Using the 1-h turnaround time "stat" potassium test as a model, we found 16 causes for test delay, of which 9 were potentially remediable. By applying these remedies, we were able to increase test compliance, in the day shift, from 91.5% (95% confidence interval 88.8%-93.7%) to 97.6% (95% confidence interval 96.4-98.55%), which is significant at P < 10(-7). This daily plot is a useful quality assurance tool, supplementing the more conventional tests used to ensure laboratory quality improvement.

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The authors evaluated the Cobas FARA centrifugal analyzer with respect to pipetting precision and accuracy, instrument temperature, spectrophotometric response, and analytic performance for the assay of five serum enzymes and glucose. Spectrophotometric response, temperature response, pipetting precision, and accuracy were satisfactory. However, sufficient time must be allowed for cuvet contents to reach a stable temperature before measurements are made. Total day-to-day imprecision (within plus between run) was less than 5% (coefficient of variation) for aspartate and alanine aminotransferases (AST; Enzyme Commission classification number [EC] EC 2.6.1.1; and ALT; EC 2.6.1.2); alkaline phosphatase (AP; EC 3.1.3.1); gamma-glutamyltransferase (GGT; EC 2.3.1.2); lactate dehydrogenase (LD; EC 1.1.1.17); creatine kinase (CK; EC 2.7.3.1); and glucose assays. Results compare well with those obtained with other current clinical chemistry analyzers; correlation coefficients were greater than 0.993. Sample-to-sample carryover was negligible, and method linearity was satisfactory for all tests.

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A MUMPS program called MAILBOX allows information to be more efficiently disseminated in a hospital department of clinical biochemistry. Readily accessible to all staff as the department is equipped with video display units in every laboratory and office, MAILBOX allows laboratory staff to send and read departmental messages; send, read, and save personal messages; sign in to and out of the department; and locate all other staff. Departmental messages containing information of general interest are automatically displayed on signing on to MAILBOX. Personal messages are directed to specific people, who are so informed when signing on; they can only be read by the sender and intended recipient(s).

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In a questionnaire response to an outbreak of erythema infectiosum in a village primary school, 55 (46%) of the 121 pupils reported an illness with rash. Three of the 12 members of staff also developed a rash. Onset in most affected children was indicated by the classical ;slapped cheek' appearance of erythema infectiosum with subsequent spread of the rash to the extremities. However, in 17 (35%) of 49 children who provided additional clinical data, the rash spread either in the reverse direction or not at all. Nineteen children (39%) reported recurrence of the rash.Serological studies confirmed that human parvovirus was the cause of the outbreak. Forty-six (44%) of 104 children investigated had significant levels of virus-specific immunoglobulin (lg)M and/or lgG antibodies consistent with recent infection. Most infections occurred in older children. Human parvovirus infection was also confirmed in five of the 12 adults. These studies revealed a substantial number of subclinical episodes - 14 (22%) of 64 subjects who remained well had serological evidence of recent infection with human parovovirus. Significantly, 43 individuals (37% of those investigated) remained seronegative despite frequent exposure to infection within the school. This finding, together with the observed temporary interruption of the outbreak which coincided with school holidays substantiates the view that human parvovirus has a relatively low infectivity and requires close person-to-person contact for its transmission.

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We describe the organization that evolved in the Clinical Biochemistry Department of a tertiary-care hospital for handling blood (serum) alcohol (volatiles) determinations. We use a microprocessor-controlled capillary gas chromatography system which will detect and quantitate methanol, ethanol, isopropanol and acetone. Minimal operator intervention is required, allowing operation of the system 24 hours each day, thus permitting timely detection of these volatiles. A Specimen Trace Card has been devised to document continuity of sample handling from the time of blood collection until completion of the analysis. This has proved of value when laboratory records are used for legal purposes.

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We measured cholinesterase (EC 3.1.1.8) and 5'-nucleotidase (EC 3.1.3.5) activities in serum of 24 healthy laboratory staff during 12 months. Overall mean activities ranged from 5.3 to 13.4 kU/L for cholinesterase and 5.4 to 9.8 U/L for 5'-nucleotidase. Cholinesterase activity was significantly (p less than 0.01) higher for men than for women. 5'-Nucleotidase activity was significantly (p = 0.01) higher for subjects 40 years or older than for those younger than 40, but was not different with respect to sex or time of year. Average intra- and interindividual variances (SD2) were 0.38 and 2.69 for cholinesterase and 1.41 and 0.97 for 5'-nucleotidase, respectively. Intra- to interindividual standard deviation ratios were 0.38 for cholinesterase and 1.21 for 5'-nucleotidase. Average within-run analytical variances were 0.13 and 0.3 (4% and 13% of total variance) for cholinesterase and 5'-nucleotidase, respectively. The importance of these findings in regards to diagnostic interpretation of serum cholinesterase and 5'-nucleotidase results is discussed.

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We evaluated the analytical performance of the EPOS (Eppendorf Patient Oriented System) Automated Selective Chemistry Analyzer, using the following tests for serum analytes: alanine and aspartate aminotransferases, lactate dehydrogenase, creatine kinase, gamma-glutamyltransferase, alkaline phosphatase, and glucose. Results from the EPOS correlated well with those from comparison instruments (r greater than or equal to 0.990). Precision and linearity limits were excellent for all tests; linearity of the optical and pipetting systems was satisfactory. Reagent carryover was negligible. Sample-to-sample carryover was less than 1% for all tests, but only lactate dehydrogenase was less than the manufacturer's specified 0.5%. Volumes aspirated and dispensed by the sample and reagent II pipetting systems differed significantly from preset values, especially at lower settings; the reagent I system was satisfactory at all volumes tested. Minimal daily maintenance and an external data-reduction system make the EPOS a practical alternative to other bench-top chemistry analyzers.

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We describe an array of checking routines that can aid laboratory staff in detecting possible errors in results being entered into a laboratory computer. A single result is checked at the worksheet stage for its numeric format and for its numeric status by comparison with appropriate reference ranges, and action and hazard limits. If a previous result exists then the present result can be compared with it (delta checking). Laboratory documentation of abnormal results is important and we describe three types; worksheet, exception report(s) and histograms of results. The clinical reports leaving the laboratory should flag abnormal results so that the clinician is prompted to examine, and question if necessary, results which are extreme or have changed significantly since the last analysis. Effective error detection requires cooperation between the laboratory and clinical units.

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The processes of order entry, urinalysis result, and isoenzyme interpretation entry into a laboratory computer system is a time consuming activity. We have designed a series of forms for use with a digitising pad that allow us rapidly to enter orders, urinalysis results, and isoenzyme interpretative comments into our laboratory computer system. We have shown that digitiser entry is always significantly faster than manual entry. Although there are many devices available to facilitate computer entry, we believe that the digitiser technique is an attractive option because of its ease of use, speed, reliability, and low cost.

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We have modified a BASIC program for serum cholinesterase phenotyping using a microcomputer. This program accepts the reaction-rate result of total and inhibitor assays of activity, allows the patient to be identified and prints out a full account of the fitting process thus allowing adequate documentation. We believe that this modification enhances the usefulness of the program to laboratories engaged in the routine determination of serum cholinesterase phenotyping.

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Methylglucamine iodipamide (Cholografin-North America; Biligrafin-Europe, Squibb) is the only contrast medium in clinical usage for opacification of the biliary tree in intravenous cholangiography. We report two cases of elevation of serum lactate dehydrogenase-5 activity following infusion of 40 ml of Cholografin. This occurred without overt clinical signs of adverse reaction to contrast medium. This elevation was 65% of serum LD-5 activity in case one, 91% in case two. The elevation peaked at 12 h after administration of contrast medium in both cases and persisted for at least 24 h. These findings suggest that methylglucamine iodipamide causes transient hepatocellular toxicity, the mechanism of which is not known.

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