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E J Adams

Publications and source records attributed to E J Adams.

At least 55 records · Page 3Linked to original sources
PubMed1996

Peptides bound endogenously by HLA-Cw*0304 expressed in LCL 721.221 cells include a peptide derived from HLA-E.

The peptide-binding specificity of HLA-Cw*0304 was determined. Sequence analysis of endogenously-bound peptides isolated from Cw*0304 expressed by LCL 721.221 (221 for short) cells transfected with Cw*0304 cDNA revealed this class I allotype preferentially binds peptides possessing alanine at position 2 and leucine or methionine at the C-terminus. One peptide isolated from Cw*0304 expressed by 221 cells has sequence identity to residues 116-126 of HLA-E. Expression of HLA-E by 221 cells was confirmed by isolation of mRNA transcripts for HLA-E*0101 and detection of beta 2-microglobulin (beta 2-m)-associated HLA-E protein.

Cell Line, Transformed↗
PubMed1995

Changes to dose in the build-up region when using multi-leaf collimators in place of lead blocks supported on an accessory tray.

Doses in the build-up region have been compared for regular fields with and without a perspex accessory tray and for two irregular fields defined by either a Philips multi-leaf collimator (MLC) or lead blocks. The results show an increase in doses within the build-up region, by up to a factor of two, primarily due to the presence of the accessory tray. Fields shaped with the MLC exhibited build-up characteristics similar to those in unblocked fields and hence there will be systematic changes to the build-up dose when treatments are transferred from lead blocking techniques to those using an MLC mounted within the treatment head.

Humans↗
PubMed1995

HLA-B16 antigens: sequence of the ST-16 antigen, further definition of two B38 subtypes and evidence for convergent evolution of B*3902.

The ST-16 antigenic specificity of the HLA-B locus is defined as a B39 variant of Mexican-Americans. Nucleotide sequencing of cDNA shows the ST-16 allele (B*3905) differs from B*39011 by a single substitution that substitutes tyrosine for aspartic acid at position 74 of the mature class I heavy chain. The complete coding region sequence for the common caucasoid allele encoding the B38 antigen has been determined. This B*3801 allele differs from B*3802 at two nucleotide substitutions within the Bw4 sequence motif. B*3801 and B*3802 may have been derived independently from B*39011 by conversion events with B alleles donating distinctive Bw4 motifs. A novel allele B*39022 derived from a Colombian Indian differs from the B*39021 allele of Japanese origin at two widely separated silent substitutions. Comparison of sequences for the known B16 alleles suggest that B*39021 and B*39022 were independently derived by recombination from B*39013 and B*39011 respectively.

Alleles↗
PubMed1995

The HLA-A,B,C genotype of the class I negative cell line Daudi reveals novel HLA-A and -B alleles.

Daudi, a lymphoblastoid B cell line derived from an African Burkitt lymphoma does not express HLA-A,B,C antigens at the cell surface. Although HLA-A,B,C heavy chains are made normally they do not assemble into functional molecules because beta 2-microglobulin is absent. Previous serological analysis of somatic cell hybrids indicated that the HLA haplotypes of Daudi encoded HLA-A1, A10(A26), B17, and B16(38) antigens. Here we describe the application of molecular methods: ARMS-PCR, cDNA cloning and sequencing, immunoprecipitation and gel electrophoresis, to define the class I genotype of the Daudi cell line which is HLA-A*0102, A*6601, B*5801, B*5802, Cw*0302 and Cw*0602. With the exception of the B38 antigen, which is not a product of the alleles defined, the genotype is consistent with the serological description. Two previously undiscovered alleles emerged from this analysis: A*0102 and B*5802. The A*0102 allele differs from A*0101 by 5 nucleotide substitutions within exon 2 where it has a motif shared with A*30 alleles; the B*5802 allele differs from B*5801 by 3 substitutions in exon 3 where it has a motif shared with B*14 alleles. Subtyping HLA-A1 alleles showed A*0102 was well represented amongst individuals typed serologically as A1 in an African population but was absent from caucasoids. B*5802 has been found in a second individual. Thus the novel A and B alleles are not specific to the Daudi tumor. Overall, this analysis of a single East African cell illustrates the power of molecular methods to define new class I HLA alleles in non-caucasoid populations.

Africa, Eastern↗
PubMed1995

Definition of a new HLA-B7 subtype (B*0704) by isoelectric focusing, family studies and DNA sequence analysis.

During screening of potential bone marrow donors, a previously undescribed banding position for the serologically defined HLA-B7 antigen was identified in three unrelated families using one dimensional isoelectric focusing and class I specific Western blot analysis. The isoelectric point of the new variant is more acidic than the two HLA-B7 variants that had been defined before. In each family the new B7 variant was found linked to HLA-A2 and -Cw7. Cloning and sequencing of full-length clones of complementary DNA showed that the new allele (B*0704) differs from B*0702, the common allele encoding HLA-B7, by three nucleotide substitutions within the codon for residue 156 of the mature heavy chain. As a result of these differences amino acid 156 is changed from arginine to aspartic acid, a difference consistent with the isoelectric points. The group of three nucleotide substitutions that distinguish B*0704 from B*0702 is present in other HLA-B alleles.

Alleles↗
PubMed1995

Expression of an unusual Bw4 epitope by a subtype of HLA-B8 [B*0802].

The primary structure of a variant HLA-B8 antigen has been determined by cDNA cloning and sequencing. The variant, B*0802 differs, from the common B*0801 subtype at positions 77-83 of the alpha 1 helix that determine the Bw4 and Bw6 public epitopes. Whereas B*0801 has the common Bw6 motif, B*0802 has the Bw4 motif found in B*13 and B*44 allotypes. Serological analysis of B cell lines expressing B*0802 and of a B*0802 transfectant made with the HLA-A,B negative cell line 721.221 shows that B*0802 reacts with Bw4-specific antibodies, but at a level much lower than expected for Bw4 positive HLA-B allotypes.

Alleles↗
PubMed1995

Comparative study of tranexamic acid and norethisterone in the treatment of ovulatory menorrhagia.

OBJECTIVE: To compare the efficacy and safety of tranexamic acid and norethisterone in the treatment of ovulatory menorrhagia. DESIGN: A randomised, double-blind, placebo controlled study. SETTING: University Department of Obstetrics and Gynaecology, Addenbrooke's Hospital, Cambridge. SUBJECTS: One hundred and three women complaining of heavy periods with a regular cycle recruited directly from general practitioners within the hospital catchment area and from consultants' gynaecology clinics. INTERVENTIONS: There were forty-six women on placebo with confirmed ovulatory menorrhagia, defined as menstrual blood loss greater than 80 ml/cycle and mid-luteal serum progesterone concentration greater than 9 nmol/l). Twenty-one received norethisterone (5 mg twice a day on days 19 and 26) and 25 received tranexamic acid (1 g four times daily on days 1 to 4) for two cycles. MAIN OUTCOME MEASURES: Menstrual blood loss was measured using the alkaline haematin method. Haematological assessments were made both at the beginning and at the end of the study, questionnaires were given to assess subjective endpoints, and patients were asked to report any adverse events during all cycles. RESULTS: Tranexamic acid reduced mean menstrual blood loss by 45%, from 175 ml to 97 ml (95% CI for the difference in menstrual blood loss 52 to 108, P < 0.0001), norethisterone increased mean blood loss by 20% from 173 ml to 208 ml (95% CI for the difference in menstrual blood loss -64 to 2, P = 0.26). Fourteen (56%) women who received tranexamic acid achieved a mean menstrual loss of less than 80 ml per cycle during treatment, but only two (9.5%) who received norethisterone achieved this mean menstrual loss. There were no serious adverse events reported for either drug. CONCLUSIONS: Tranexamic acid is a safe and effective form of medical therapy in women with menorrhagia and is highly likely to normalise blood loss in women losing 80 to 200 ml prior to treatment. Norethisterone at this dose is not effective therapy for ovulatory menorrhagia.

Adolescent↗
PubMed1994

Physical activity and growth of Kenyan school children with hookworm, Trichuris trichiura and Ascaris lumbricoides infections are improved after treatment with albendazole.

Growth, activity, appetite and intestinal helminth infections were compared for 55 Kenyan primary school children with hookworm (93% prevalence), T. trichiura (84% prevalence) and A. lumbricoides (29% prevalence) before and 9 wk after treatment with three 400-mg doses of albendazole (Zentel) or placebo. Fecal samples were examined for helminth eggs using a modified Kato technique. Activity was measured during free-play with motion recorders on the dominant thigh. Children rated their appetites on a 5-point scale. After baseline measurements, children were randomly allocated to the albendazole-treated (n = 28) and placebo (n = 27) groups, treated, and re-examined 9 wk later. At follow-up, egg counts were significantly lower than at baseline in the albendazole-treated group (P < or = 0.002), and gains in activity, reported appetite and most indices of growth were significantly greater for the albendazole-treated group than for the placebo group. We conclude that treatment of undernourished school children for intestinal helminth infections with albendazole may improve growth and appetite and increase spontaneous physical activity.

Albendazole↗
PubMed1994

The HLA-B73 antigen has a most unusual structure that defines a second lineage of HLA-B alleles.

The nucleotide sequence of cDNA encoding the HLA-B73 antigen was determined; it is unusually divergent, differing from other HLA-B alleles by 44-77 nucleotide substitutions. Features that distinguish the B*7301 heavy chain from other HLA-B heavy chains include multiple substitutions in the alpha 3 domain and a duplication-deletion within the transmembrane region that increases the length of B*7301 compared to other HLA-B heavy chains. The duplication-deletion is shared with subsets of B alleles from the homologous gorilla (Gogo-B) and chimpanzee (Patr-B) loci. Other unusual features of B*7301 are individually shared with certain alleles of the HLA-A, HLA-C, HLA-F, Gogo-B and Patr-B loci. The B*7301 molecules has sequence elements in common with members of the B7 crossreacting group in the alpha 1 domain and is shown to possess the ME1 epitope, which is held in common with the B7, B22, B27, B42 and B67 antigens. B*7301 has a unique cysteine at position 270 of the alpha 3 domain which appears accessible but probably does not form disulphide-bonded B*7301 dimers in cell membranes. B*7301 represents a newly discovered but ancient lineage of HLA-B alleles that appears poorly represented in the modern human population.

Alleles↗
PubMed1994

A small test of a sequence-based typing method: definition of the B*1520 allele.

Santamaria et al. (Human Immunology 1993 37: 39-50) describe a method of sequence-based typing (SBT) for HLA-A, B and C alleles said to give "unambiguous typing of any sample, heterozygous or homozygous, without requiring additional typing information". From SBT analysis, which involves determination of partial sequences of mixed alleles, these investigators reported that cell lines KT17 (HLA-B35,62) and OLGA (HLA-B62) from the reference panel of the 10th International Histocompatibility Workshop express novel variants of HLA-B15 (B1501-MN6) and HLA-B35 (B3501-MN7) respectively. To study further the novel alleles, we cloned and sequenced full-length HLA-B cDNA clones isolated from the KT17 and OLGA cell lines. We find that KT17 expresses B*3501, as assigned by SBT, and B*1501, the common allele encoding the B62 antigen. We were unable to confirm that KT17 expresses the novel B1501-MN6 variant identified by SBT. For OLGA our analysis confirms the partial sequences obtained by SBT. Thus OLGA expresses B*1501 and a novel HLA-B allele. The complete sequence of the latter shows it is a hybrid having exons 1 and 2 in common with B*1501 and other B15 subtypes and exons 3-7 in common with B*3501 and related molecules including B*5301 and B*5801. The novel allele has been designated B*1520 because of its sequence similarity with the B15 group; furthermore, serological analysis shows that the B*1520 product does not express epitopes in common with either B35, B53 or B58. The B*1520 heavy chain has a similar isoelectric point to A*3101; B*1520 was undetected by previous applications of isoelectric focusing because B*1520 and A31 are both expressed by OLGA. In conclusion, HLA-B typing of two cell lines by cDNA cloning and sequencing gives concordant results with SBT for three of the four alleles. The cause of the discrepancy for the fourth allele is unknown, however, this finding indicates that the novel HLA-A, B and C sequences emerging from SBT studies need independent verification.

Alleles↗
PubMed1994

Sexually transmitted diseases in transient British forces in the tropics.

OBJECTIVE: To compare the incidence of sexually transmitted diseases (STD) in British troops in the tropics with that in a standard population. DESIGN: Retrospective analysis of STD clinic records over one calendar year. SETTING: A British Military Hospital in the Tropics serving 1441 resident personnel. SUBJECTS: All patients attending a STD clinic. MAIN FINDINGS: 815 cases of STD were recorded during the study period, giving incidence rate of 56,558 per 100,000 population per year. When compared with a matched population from England and Wales, the age standardised relative risk for STD amongst tropical troops was 25.0 (95% confidence interval 24.9 to 25.1). Thirty nine percent of cases reported prostitute contact as a source of their disease. Of patients questioned about condom usage, 70% reported that they did not normally use a condom. CONCLUSIONS: British troops spending short periods of time in a tropical environment are significantly more likely to acquire a STD than men in the same age groups in England and Wales. The proportions of cases who reported that they did not use condoms and the number who cited prostitute contact as a source of infection indicate that even greater sexual education of troops on deployment overseas may be required.

Adolescent↗
PubMed1993

Weight gain of Kenyan school children infected with hookworm, Trichuris trichiura and Ascaris lumbricoides is improved following once- or twice-yearly treatment with albendazole.

We studied growth in infected children given one dose (600 mg) or two doses of albendazole per school year. Children were examined and allocated at random within sex by descending hookworm egg count to one of three groups: placebo (n = 93), one dose (1x, n = 96) or two doses (2x, n = 95). Each child was treated and then re-examined and treated 3.6 and 8.2 mo later (Exams 2 and 3). The 1x and 2x groups gained significantly more by Exam 3 than the placebo group in weight (1.1 and 0.9 kg more, respectively), percent weight-for-age (3.3 and 2.7 percentage points more), percent weight-for-height (3.1 and 2.9 percentage points more), percent arm circumference-for-age (2.3 and 2.0 percentage points more) and triceps and subscapular skinfolds but did not differ significantly from each other. The placebo group showed significant decreases between exams (P < 0.0002) in percent weight-for-age and percent arm circumference-for-age and no change in percent weight-for-height, whereas the 1x and 2x groups exhibited significant increases (P < 0.005). At Exam 3, arithmetic mean egg reduction rates for the 1x and 2x groups were 84 and 95% for hookworm, 42 and 32% for Trichuris and 55 and 87% for Ascaris, respectively. We conclude that one or two doses of albendazole per year resulted in similar growth improvements, despite reinfection, in school-age children in an area where these helminths and poor growth are prevalent.

Albendazole↗