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L New

Publications and source records attributed to L New.

28 records · Page 2Linked to original sources
PubMed1993

The yeast gene MSH3 defines a new class of eukaryotic MutS homologues.

We have identified a gene in Saccharomyces cerevisiae, MSH3, whose predicted protein product shares extensive sequence similarity with bacterial proteins involved in DNA mismatch repair as well as with the predicted protein product of the Rep-3 gene of mouse. MSH3 was obtained by performing a polymerase chain reaction on yeast genomic DNA using degenerate oligonucleotide primers designed to anneal with the most conserved regions of a gene that would be homologous to Rep-3 and Salmonella typhimurium mutS. MSH3 seems to play some role in DNA mismatch repair, inasmuch as its inactivation results in an increase in reversion rates of two different mutations and also causes an increase in postmeiotic segregation. However, the effect of MSH3 disruption on reversion rates and postmeiotic segregation appears to be much less than that of previously characterized yeast DNA mismatch repair genes. Alignment of the MSH3 sequence with all of the known MutS homologues suggests that its primary function may be different from the role of MutS in repair of replication errors. MSH3 appears to be more closely related to the mouse Rep-3 gene and other similar eukaryotic mutS homologues than to the yeast gene MSH2 and other mutS homologues that are involved in replication repair. We suggest that the primary function of MSH3 may be more closely related to one of the other known functions of mutS, such as its role in preventing recombination between non-identical sequences.

Adenosine Triphosphatases↗
PubMed1991

Bronchoalveolar lavage in the prediction of post-thoracotomy chest infection.

A prospective study was carried out on 75 patients undergoing pulmonary surgery to determine the relationship between perioperative lung flora and postoperative infections. Seventy-five patients having pleurectomy or pneumonectomy received cefuroxime prophylaxis; 1.5 g i.v. at induction followed by 6 further doses of 0.75 g i.v. over 48 h. Bronchoalveolar lavage samples were taken perioperatively via bronchoscopy in pleurectomy patients and from excised lung in patients undergoing lung resection. Patients were monitored for development of chest infection during the first 10 days after operation. Bacterial pathogens were cultured from 12 out of 54 lavage samples. The most common pathogen was Haemophilus influenzae and all the organisms were sensitive to cefuroxime. Eight patients (10.7%) developed postoperative chest infection. The likelihood of developing postoperative chest infection was 42% (5 out of 12 patients) in those patients whose lavage culture was positive for bacterial pathogens compared to 4.8% (2 out of 42 patients) for those whose culture was negative (chi 2 test, p less than 0.001). These results suggest that the culturing of bacterial pathogens from lavage samples from resected lung is a significant predictor of postoperative chest infection in patients undergoing pulmonary resection.

Bronchoalveolar Lavage Fluid↗
PubMed1989

Gene engineering by selectable intraplasmid recombination: construction of novel dihydrofolate reductase minigenes.

An intraplasmid recombination system in Escherichia coli has been designed to make possible the engineering of various genes using methods that greatly reduce dependence on appropriately placed restriction enzyme sites. This system has been used to manipulate intervening sequences in dihydrofolate reductase minigenes and to vary the number of 48-bp repeats in the promoter region. In this method, the two fragments to be recombined are cloned into a plasmid separated by a fragment of DNA containing an expressible galactokinase-encoding gene (galK). Selection for loss of the galK gene, but for retention of the plasmid in E. coli, results in a plasmid in which the two fragments have undergone homologous recombination. Several new plasmids are reported here which contain an expressible galK gene flanked by multiple restriction sites. These plasmids should be useful in recombination and as convenient sources of a gene for which both positive and negative selections are available in E. coli.

Animals↗
PubMed1989

Assessment of immunoglobulin-M immunosorbent agglutination assay (ISAGA) for detecting toxoplasma specific IgM.

An immunoglobulin-M immunosorbent agglutination assay (ISAGA) was introduced to detect toxoplasma specific IgM. This assay incorporates mu chain capture and use of entire toxoplasma trophozoites as an antigen source. The performance of the ISAGA was compared with that of a double sandwich enzyme linked immunosorbent assay (DS-ELISA) currently used in the Public Health Laboratory Service Toxoplasma Reference Laboratories. The ISAGA was found to be more sensitive than DS-ELISA but there was no demonstrable difference in the specificity or reproducibility between the two assays. The ISAGA is suitable for the diagnosis of acute toxoplasmosis in immunocompetent patients and as a screening test for recent infection in pregnant women. The persistence of ISAGA reactivity, however, is such that additional serological assessment is required to define the risk of congenital infection.

Agglutination Tests↗
PubMed1989

Discrepant toxoplasma latex agglutination test results.

The analysis of 4450 toxoplasma serology results showed that 59 (1.3%) latex agglutination reactions were not confirmed in the dye test. These discrepant results were associated with an unspecified IgM antibody but not associated with kit batch variation, inactivation of sera, concurrent cytomegalovirus infection, or the presence of hepatitis B virus "e" antigen. The latex agglutination test is useful as a screen for toxoplasma infection but false positive reactions do occur. Patients at risk of severe toxoplasmosis should be investigated by additional tests.

Animals↗
PubMed1989

Direct agglutination test and other assays for measuring antibodies to Toxoplasma gondii.

The performance of a direct agglutination test for the detection of toxoplasma specific IgG immunoglobulin was compared with that of the latex agglutination test. The direct agglutination test was less sensitive but more specific than the latex agglutination test. Quantitative results were not directly comparable, reflecting the different antibody profiles detected in each assay. The direct agglutination test represents an alternative to the latex agglutination test as a screening test for toxoplasmosis. Patients at risk of life threatening infection require detailed serological examination using additional assays.

Agglutination Tests↗
PubMedDate not supplied

Epileptic seizures and malaria in Kenyan children.

Between October 1990 and November 1991 data were collected on the frequency, causes, and nature of epileptic seizures in children admitted to the paediatric ward at Kilifi District Hospital, Kenya, from a defined study area. During this period, 1324 children were studied, of whom 15.8% had seizures as part of their illness. Malaria was by far the commonest cause of seizures, accounting for 69.0%; no other single condition caused more than 4.4%. The proportion of respiratory infections complicated by seizures was 4.0% compared to 31.3% for malaria. Only 25% of malaria-related epileptic seizures were associated with cerebral malaria; the remainder were associated with otherwise uncomplicated malaria and, in this group, 84% had complex seizures, with 47% being partial and over 70% repetitive. There was no relationship with fever, with 54% of observed seizures occurring at rectal temperatures below 38 degrees C. The minimum community incidence of complex seizures in association with non-cerebral malaria was 5.8 per 1000 per year. Complex epileptic seizures in association with otherwise uncomplicated malaria are common and may be a significant cause of longer term morbidity in malaria endemic areas.

Age Factors↗
PubMedDate not supplied

Malaria is an important cause of anaemia in primigravidae: evidence from a district hospital in coastal Kenya.

A study was undertaken in order to determine the prevalence and aetiology of anaemia in pregnancy in coastal Kenya, so as to establish locally important causes and enable the development of appropriate intervention strategies. 275 women attending the antenatal clinic at Kilifi district hospital, Kenya, were recruited in November 1993. The prevalence of anaemia (haemoglobin [Hb] < 11 g/dL) was 75.6%, and the prevalence of severe anaemia (Hb < 7g/dL) was 9.8% among all parities; 15.3% of 73 primigravidae were severely anaemic, compared with 7.9% of 202 multigravidae (P = 0.07). In primigravidae, malaria infection (Plasmodium falciparum) was strongly associated with moderate and severe anaemia (chi 2 test for trend, P = 0.003). Severe anaemia was more than twice as common in women with peripheral parasitaemia as in those who were aparasitaemic, and parasitaemia was associated with a 2.2g/dL decrease in mean haemoglobin level (P < 0.001). In multigravidae, iron deficiency and hookworm infection were the dominant risk factors for anaemia. Folate deficiency and human immunodeficiency virus infection were not strongly associated with anaemia. It is suggested that an intervention that can effectively reduce malaria infection in primigravidae could have a major impact on the health of these women and their infants.

Anemia↗
PubMedDate not supplied

Acridine orange fluorescence techniques as alternatives to traditional Giemsa staining for the diagnosis of malaria in developing countries.

Traditional Giemsa-stained thick blood films were compared with 2 fluorescence microscopy techniques, acridine orange (AO) staining of thin blood films and the quantitative buffy coat (QBC) method, for the microscopical diagnosis of malaria. Of 200 samples examined, 141 were positive by Giemsa staining, 146 by AO and 137 by QBC. Overall sensitivities for the 2 fluorescence techniques compared to Giemsa staining were good: AO 97.9% and QBC 93.6%. However, with parasitaemias < 100/microL the QBC sensitivity fell to 41.7% whereas that of AO was 83.3%. Both AO and QBC were unable to differentiate accurately between individual malaria species. We conclude that the QBC technique alone cannot replace Giemsa-stained thick blood films for most purposes in an African setting. However, apart from species differentiation, the AO method is an appropriate technique for the laboratory diagnosis of malaria in developing countries.

Acridine Orange↗