The use of car restraints by newborns and mothers: knowledge, attitudes and practices

Knowledge, attitudes and practices with regard to car safety were studied among 403 parturient women in Jerusalem. The mean knowledge score was 22 out of a total of 32. Attitudes towards seat belt use were positive. Regular use of the seat belt was reported by 36% of the women, but the intent to take the newborn in a car seat for the first ride (from the hospital) was reported by only 8% of the mothers. Knowledge of car safety and mother's seat belt use was significantly associated with the intent of car seat use for the newborn. Sociodemographic variables were not associated with the intent to use a car seat for the newborn. We conclude that laws for mandatory use of seat belts in cities and car restraints for children are needed, and we suggest integration of promotion programs within the existing health services.

Identification and genetic mapping of proteins encoded in the fimbrial subunit gene region of Bacteroides nodosus

The fimbriae produced by the anaerobic bacterium Bacteroides nodosus are important in the pathogenesis of ovine foot rot. Studies on other microorganisms have shown that the genes coding for the production and assembly of fimbriae are often clustered. By the use of maxicells, transposon mutagenesis and expression vectors, we have identified several genes which are located in the fimbrial subunit gene region. Antiserum was prepared against one of the proteins (88 kDa) which we were able to overproduce in Escherichia coli. In Western blots, these antibodies reacted with an 88 kDa protein located in the B. nodosus cell membrane. However, they did not react with the putative basal protein which is found in fimbrial preparations. We concluded that in B. nodosus the genes involved in fimbrial assembly are not all localised to one small region of the genome. In addition, our studies showed that although the fimbrial subunits are not assembled into intact fimbriae, an N-terminal sequence is processed in E. coli.

Pasteurella multocida infections in mice with reference to haemorrhagic septicaemia in cattle and buffalo

Haemorrhagic septicaemia (HS) is an infectious disease of cattle and buffalo caused by particular serotypes of Pasteurella multocida and is one of the most economically important livestock diseases in South-East Asia. While HS has been recognized for many years, very little is understood about the disease, primarily because of the expense of cattle and a lack of suitable animal models. The suitability of using mice to study HS was assessed using parameters such as the critical pathogenic dose, kinetics of infection, pathology of disease and resistance to reinfection. Pasteurella multocida M1404, the type strain for Carter group B, the serotype responsible for Asian HS, was injected intraperitoneally into BALB/c mice. As few as 20 colony forming units produced an overwhelming septicaemia in mice in less than 30 h. The kinetics of infection demonstrated a very rapid in vivo multiplication rate. There was no evidence of inhibition of bacterial cell growth by natural host defence mechanisms, even with the very small inocula used. The gross pathology of the disease in mice was characterized by splenomegaly, lymphadenopathy and petechial haemorrhages similar to that observed in cattle and buffalo with HS. Mice were found to develop a short-lived resistance to reinfection following a primary infection which had been successfully treated with antibiotics. The mouse would seem to provide an ideal tool by which to study HS, but warrant further studies in order to be able to critically assess it as a model for this economically important disease.

The distribution and localization of the stage-specific GP31 antigen from infective Ostertagia circumcincta larvae

The 31,000 mol. wt glycoprotein (GP31) antigen of infective third-stage (L3) Ostertagia circumcincta larvae was shown, by surface labelling experiments and immunofluorescent antibody staining of whole larvae and larval sections, to be distributed internally. When transverse sections of L3 O. circumcincta, taken from the anterior pharyngeal region, were further examined by electron microscopy, after immunogold staining with rabbit anti-GP31 antiserum, the GP31 antigen was found to be specifically located in 'secretory organelles' within the cells of the oesophageal glands. By in vitro culturing L3 O. circumcincta in medium supplemented with 35S-methionine and then analysing the excretory-secretory material released by the larvae, it was found that the GP31 molecule was one of the major components of the excretory-secretory complex. The purified GP31 molecule had no detectable proteolytic activity in protein degradation assays. On examination of Triton X-100 extracts of infective larvae from other nematode parasite species, a predominant antigen similar to GP31 was found in Trichostrongylus colubriformis and Haemonchus contortus, but in Toxocara canis a minor component corresponding in mol. wt to GP31 was also detected. Based on these results the possible role of GP31 as a candidate antigen for a broad spectrum molecular vaccine against gastrointestinal nematode parasites in sheep is discussed.

Excision of transposon Tn917 in Bacillus subtilis

Excision of Tn917 from chromosomal sites in B. subtilis is characterized by reversion studies. We propose different modes of excision depending on the site of transposon insertion. Excision takes place as precise excision in one step which results in reversion of the mutant phenotype, or by a two-step process where nearly precise excision of the transposon moiety is followed by precise excision of the nearly precise excision remnants. For this type of transposons a minor pathway or nonreplicative transposition is proposed to be connected with precise excision.

Process and outcome evaluation of preventive care for infants in two types of practices

Process and outcome of preventive and promotive infant care have been evaluated in a maternal and child health (MCH) service and compared with that of a comprehensive care family practice (FP), both serving a low middle class population in West Jerusalem. Both services are provided by the Community Health Center of the Department of Social Medicine. Community oriented primary care is integrated into the practices, including ongoing surveillance of the communities' health status. Preventive and promotive programs have been developed, implemented and evaluated. The process evaluation indicated a similar use of the preventive service in the MCH and FP services. Some of the routines were carried out to a lesser extent in the FP than in the MCH framework, such as growth monitoring, hearing tests and advice on iron supplementation. The small difference in compliance with routines did not affect a child's growth between birth and one year of age, but the anemia rate in the FP practice was higher than in the MCH practice. The high level of care and relatively small differences in process and outcome between the two types of services have been achieved by ongoing inservice training, a high level of personnel, similar protocols and supervision in both practices.

Conversion of a Golgi apparatus sialyltransferase to a secretory protein by replacement of the NH2-terminal signal anchor with a signal peptide

The beta-galactoside alpha 2,6 sialyltransferase, an integral membrane protein localized to the trans-region of the Golgi apparatus, has been converted into a catalytically active secreted protein by the replacement of the NH2-terminal signal-anchor domain with the cleavable signal peptide of human gamma-interferon. Pulse-chase analysis of the wild type and recombinant proteins expressed in stably transfected Chinese hamster ovary cells showed that the wild type sialyltransferase (47 kDa) remained cell-associated. In contrast, the signal peptide-sialyltransferase fusion protein yielded an enzymatically active 41-kDa polypeptide which was secreted with a half-time of 2-3 h, consistent with cleavage of the signal peptide. The data indicate that the catalytic domain does not contain sufficient information for retention in the Golgi apparatus and that retention signals are likely to be found in the NH2-terminal 57 amino acids of the wild type enzyme.

Characterization and taxonomic significance of lipopolysaccharides of Leptospira interrogans serovar hardjo

Lipopolysaccharides (LPSs) from Leptospira interrogans serovar hardjo (reference strain hardjoprajitno and strain hardjobovis) were prepared by the hot phenol-water procedure. High yields of LPSs were found in the phenol phase. Gel electrophoresis of the phenol phase LPSs showed similar patterns for all strains in contrast to the different patterns found in the water phase LPSs. Sugar composition was also similar among all strains with rhamnose as the predominant sugar. Mannosamine was detected by high performance thin layer and gas-liquid chromatography. 2-Keto-3-deoxyoctonic acid (KDO) was comparable with authentic KDO by paper chromatography. Periodate oxidation at near neutral pH with or without prior hydrolysis showed that most of the KDO was substituted. The fatty acid composition of strain hardjobovis LPS was slightly different from that of the reference strain hardjoprajitno. Myristic and 3-hydroxymyristic acid were not detected in any of the LPS preparations. In conjunction with genetic and other data, the two strains are sufficiently different to be regarded as members of two separate species sharing common antigens. There is sufficient evidence to rename the hardjoprajitno strain type L. interrogans hardjo-p, and the hardjobovis strain type L. borgpeterseni hardjo-b.

Leptospira interrogans serovar hardjo is not a major cause of bovine abortion in Victoria

The aim of this study was to determine whether evidence could be obtained of foetal infection with Leptospira interrogans serovar hardjo in aborted foetuses collected from dairy farms. Material from 197 abortions occurring over a wide area of Victoria was collected over 3 years. None of 195 foetal kidney cultures or 7 cultures from membranes was positive for leptospiral organisms. Immunogold silver staining for leptospires was performed on sections of kidneys, lungs or heart from 156 foetuses, with negative results. Evidence of transient leptospiral infection in 11 of 123 foetuses was obtained by foetal heart blood serology. Two isolates of L. interrogans serovar hardjo were obtained from the urine of milking cows. These strains were examined by restriction endonuclease analysis and both were shown to be of the genotype Hardjobovis, as have been all Australian isolates studied so far. It appears that foetal infection with serovar hardjo is not associated with any substantial proportion of bovine abortions in Victoria, in contrast to the situation in Northern Ireland. The apparent absence from Victoria of the pathogenic genotype Hardjoprajitno is a possible explanation.

Functional organization and nucleotide sequence of virulence Region-2 on the large virulence plasmid in Shigella flexneri 2a

The 7 kb virulence Region-2 of the large (virulence) plasmid in Shigella flexneri 2a encodes several proteins required for invasion of intestinal epithelial cells. Insertion and deletion mutagenesis, DNA subcloning and SDS-polyacrylamide gel electrophoresis of proteins synthesized in minicells demonstrated five genes in this region. They encode 24, 18, 62 (IpaB), 41 (IpaC) and 37 (IpaD)-kiloDalton (kD) proteins. Complementation of Tn5-induced mutations in Region-2 with the above plasmid constructs indicated that Region-2 consists of two operons and that the three Ipa proteins are essential for the virulence phenotype. The transcriptional organization determined by Northern blotting, S1 nuclease protection and the effect of Tn5 insertions on expression of the Ipa proteins revealed that Region-2 has three promoters that transcribe RNAs of 4.0, 4.5 and 7.5 kb. The 4.0 kb RNA was the transcript for the operon encoding the 24, 18 kD, IpaB and C proteins and the 4.5 kb RNA for the ipaD gene. In addition, the full-length RNA of 7.5 kb which covers Region-2 supplemented full expression of the Ipa proteins. The 7663 nucleotides of Region-2 were determined to confirm the five open reading frames encoding 23,655, 17,755, 62,168, 41,077 and 36,660 Dalton proteins, respectively, and their regulatory sequences.

Extraction and identification of a 31,000 mol.wt glycoprotein antigen of Ostertagia circumcincta by sera from resistant sheep

Under similar extraction conditions, Triton X-100 sonicates gave higher yields of protein from third stage larvae and adult O. circumcincta than seven other detergents tested. Using sera from sheep which had been experimentally defined by both immunological and parasitological parameters as being either resistant or susceptible to O. circumcincta, a molecule from Triton X-100 extracts of third stage O. circumcincta larvae was identified which reacted preferentially with sera from resistant sheep. This molecule has a molecular weight of 31,000 and preliminary characterization studies revealed it to be a glycoprotein which was not found in later larval stages or adult worms. Antibodies to this 31,000 mol.wt antigen were present in sera of sheep as early as 3 weeks after experimental infection with O. circumcincta.

Detection of leptospires in pig kidney using DNA hybridisation

DNA hybridisation detected leptospiral organisms in homogenised kidneys from experimentally infected pigs, and in homogenates of pig kidneys collected at abattoirs. The technique is easy to perform and had some advantages over cultural and histological methods, in permitting the rapid survey of many kidneys simultaneously. Leptospires added to a homogenate of uninfected kidney could be detected at 10(2) organisms ml-1 by DNA hybridisation, but the technique appeared to be less sensitive than culture.

Experimental immunisation of hamsters with lipopolysaccharide antigens of Leptospira interrogans

Hamsters were immunised with leptospiral lipopolysaccharide (LPS) or the polysaccharide (PS) fraction of LPS from Leptospira interrogans serovar copenhageni and the antibody responses were measured by agglutination tests. Maximum titres were observed approximately 6 weeks after immunisation and protection against lethal challenge with the homologous strain was afforded by immunisation with as little as 2.5 micrograms of LPS or PS. All animals produced IgM agglutinins but a higher proportion of-animals immunised with PS produced IgG agglutinins than did those immunised with LPS. Immunisation of guinea-pigs with autoclaved PS showed that the preparation retained some but not all of its immunogenic activity.

A dual transcriptional activation system for the 230 kb plasmid genes coding for virulence-associated antigens of Shigella flexneri

The expression of plasmid-encoded, invasion-related antigens lpa b, c and d of Shigella flexneri was found to be positively regulated at transcriptional level by a 33kD protein produced by the previously defined, virulence-associated Region 1 on the SalI fragment B of the 230 kb invasion plasmid. The gene (designated virB) was identified and its nucleotide sequence determined. No Ipa b or c was produced in the absence of an intact virB gene although lower levels of d were produced. The previously reported regulatory activity of the virF gene some 30 kb distance away was shown to act exclusively through virB. In contrast, the activation of the virG gene necessary for intercellular spread occurred directly by virF without the requirement for virB. This study thus ascribes a critical function to a previously recognized, but functionally undefined, virulence locus on the large invasion plasmid of S. flexneri. The virF gene appears to have a central role in activation of the 230 kb plasmid-encoded virulence genes.

A follow-up study of adiposity and growth of Jerusalem schoolchildren from age 6 to 14 years

This study evaluated growth and change in adiposity from childhood to early adolescence in 587 Jerusalem schoolchildren examined in both the first and eighth grades. Mean body mass index, height, and weight were determined according to demographic variables and menstrual status and were compared to international reference populations. Menstruating females were taller and heavier than nonmenstruating females at both ages and were more overweight at age 14 years. Height and weight were positively correlated with social class for boys, and few differences were found among ethnic groups. Study subjects were shorter than reference subjects, and study girls were more overweight than reference girls at age 14 years. Our findings suggest that previously demonstrated ethnic differences in growth and adiposity among Israeli children are disappearing. Adolescent girls appear to be at greatest risk for developing obesity. The relationship of pubertal status to body size and obesity at and between the two ages is discussed.

Childhood injuries: a population-based study of emergency room visits in Jerusalem

A study of childhood injuries of 0-17-year-old Jewish children based on emergency room records of the four major hospitals and the first aid stations was conducted in Jerusalem during 1986. The incidence of visits was 99.7/1000 child-years with 95% confidence intervals (CI) = 98.0-101.5. The rate was 97.2/1000 child-years (CI = 94.4-100.0) among the 0-5-year-old, 114.6/1000 child-years (CI = 111.3-118.0) in the 6-12 age group, and was 93.6/1000 child-years (CI = 90.1-97.1) among 13-17-year-old. The male to female rate ratio was 1.7 for the 0-5-year-olds, 2.1 for the 6-12-year-olds and 2.3 for the 13-17-year-olds. The most frequent causes of injuries were falls, 38.5/1000 child-years (CI = 37.4-39.6), being struck or caught, 21.1/1000 child-years (CI = 20.3-21.9), and road accidents, 5.4/1000 child-years (CI = 5.0-5.8). Only burns among children aged 6 years and over and poisoning among 13-17-year-olds showed a higher incidence among females than among males. The head was the most frequently injured part of the body (45.2/1000 child-years, CI = 44.0-46.4). Head injuries decreased as age increased, while injuries to the extremities and trunk increased with increasing age. Two per cent of the injured children were admitted to hospital.

Trends in sibling correlations for height and weight: the effect of age changes (0-24 months) and spacing between siblings (0-10 years)

Familial correlations were studied in a sample of 618 sibships from a western neighborhood of Jerusalem, whose height (H) and weight (W) were measured longitudinally at the same age, from birth to 3 years of age. Covariate adjustments were applied to correct for change in mean of H and W with the sex of child and age of mother and for the effect of origin, education, and socioeconomic status of the mother, parity, and calendar year at birth. The highest sibling correlations were observed at birth or 1 month later (r = 0.45-0.46). Pooled sibling correlations were lower 6 months later (r = 0.33; r = 0.26 for H and W, respectively) and tended to increase again 12-18 months after birth. A clear trend of decline in sib-sib correlation for H and W measured 3 and 12 months after birth with increased spacing between siblings was observed. Our data provide evidence for transient environmental factors as possible sources of the observed temporal variation in sibling correlation for height and weight.

Effectiveness of iron supplementation compared to iron treatment during pregnancy

This study presents the evaluation of an iron supplementation program in a community by comparing 478 pregnant women who received iron supplementation from the 4th month of pregnancy, with 392 pregnant women who received iron treatment only if their Hb level was less than 12 gm/dl, and had no supplementation. In the supplementation group, no statistically significant associations were found between compliance with age, education, social class or parity. Pregnant women of European-American origin showed higher rates of good compliance than those of Asian-African origin. The mean decrease of haemoglobin (Hb) and haematocrit (Hct) between the second and third trimester of pregnancy was smaller in the supplementation group (-0.9 gm/dl Hb, -2.1% Hct) than in the treatment group (-1.1 gm/dl Hb; -3.3% Hct). The differences between the two groups were significant only for the Hct levels (P = 0.022). The mean Hb and Hct levels during the third trimester of pregnancy were higher for good compliers (11.7 gm/dl Hb; 33.6% Hct) than for poor compliers (11.4 gm/dl Hb, 32.6% Hct).

Monoclonal antibodies reacting with serogroup and serovar specific epitopes on different lipopolysaccharide subunits of Leptospira interrogans serovar pomona

Monoclonal antibodies with two kinds of specificities, produced against Leptospira interrogans serovar pomona, were studied by agglutination and immunoblotting. Antibodies reacted either exclusively with serovar pomona or with all members of the Pomona serogroup, but none of the antibodies reacted with representative serovars of other serogroups. Both antibodies recognized epitopes on purified lipopolysaccharide (LPS) from serovar pomona. In immunoblotting experiments the serogroup specific antibody recognized both the major LPS bands of 21 kDa and 26 kDa whereas the serovar specific antibodies reacted only with the 26 kDa band, thus localizing serovar specificity in the 26 kDa band and serogroup specific epitopes on at least two different LPS subunits.

Expression of two conserved leptospiral antigens in Escherichia coli

The genes encoding two protein antigens of Leptospira interrogans serovar pomona were cloned and expressed in Escherichia coli. Rabbit antisera raised against the cloned proteins, designated p12 and p20, were used to identify the antigens in Western blots of disrupted leptospiral cells. The proteins p12 and p20 were conserved within the genus Leptospira and were not detected in Leptonema illini. Although both proteins were present in leptospiral outer envelope preparations they did not elicit the production of agglutinating or opsonising antibodies.

Variants of human tissue-type plasminogen activator that lack specific structural domains of the heavy chain

The heavy chain of tissue plasminogen activator (t-PA) consists of four domains [finger, epidermal-growth-factor (EGF)-like, kringle 1 and kringle 2] that are homologous to similar domains present in other proteins. To assess the contribution of each of the domains to the biological properties of the enzyme, site-directed mutagenesis was used to generate a set of mutants lacking sequences corresponding to the axons encoding the individual structural domains. The mutant proteins were assayed for their ability to hydrolyze artificial and natural substrates in the presence and absence of fibrin, to bind to lysine-Sepharose and to be inhibited by plasminogen activator inhibitor-1. All the deletion mutants exhibit levels of basal enzymatic activity very similar to that of wild-type t-PA assayed in the absence of fibrin. A mutant protein lacking the finger domain has a 2-fold higher affinity for plasminogen than wild-type t-PA, while the mutant that lacks both finger and EGF-like domains is less active at low concentrations of plasminogen. Mutants lacking both kringles neither bind to lysine-Sepharose nor are stimulated by fibrin. However, mutants containing only one kringle (either kringle 1 or kringle 2) behave indistinguishably from one another and from the wild-type protein. We conclude that kringle 1 and kringle 2 are equivalent in their ability to mediate stimulation of catalytic activity by fibrin.

Reaction of monoclonal antibodies with species specific determinants in Leptospira interrogans outer envelope

A set of 24 monoclonal antibodies (MABs) was produced against an outer envelope preparation from Leptospira interrogans serovar copenhageni. The MABs reacted in enzyme immunoassay with species-specific determinants of an antigen in the leptospiral outer envelope (OE) of pathogenic but not of saprophytic species of Leptospira. The MABs did not agglutinate whole leptospires, nor could they opsonise homologous leptospires for phagocytosis by mouse macrophages or protect new-born guinea-pigs against lethal infection. The MABs reacted by Western blotting with a 35 x 10(3)-mol-wt band in OE separated on SDS-polyacrylamide gels, and also reacted with other bands to a lesser extent. The determinants to which the MABs were directed were localised in the leptospiral OE by immunogold labelling techniques.