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A McNicholas

Publications and source records attributed to A McNicholas.

16 recordsLinked to original sources
PubMed2005

A novel HLA-B*55 allele, HLA-B*5514, found in a DNA sample derived from a bone marrow donor.

In this study, we report the identification of a new human leucocyte antigen-B (HLA-B) allele in a sample that was found in our routine typing. This novel allele, officially designed HLA-B*5514, was found in a male donor of Bavarian Caucasoid origin (Laboratory code: 117562) typed in order for a request of the bone marrow donor registry Aktion Knochenmarkspende Bayern. Although this novel allele was added to the HLA-B*55 family by the Nomenclature Committee, the next related alleles were found in the HLA-B*56 group; HLA-B*5612 differing in six positions from HLA-B*5514 is the closest related allele.

Adult↗
PubMed2005

A novel A*24 allele, A*2442, was detected through routine bone marrow donor screening.

In this article, we report the identification of a new HLA-A allele found in a DNA sample which was part of the routine bone marrow donor typing performed in our laboratory. This novel allele officially designated as A*2442 was found in a sample from a female Caucasoid donor (Franken, Bavaria, Germany; lab code 142654) and differs from the closest related allele A*2408 by two nucleotide exchanges. In position 81, the A (A*2408) is changed to 81 C in the novel allele A*2442, resulting in an amino acid substitution at codon 27, glutamine (A*2408) is replaced by histidine ((31)Gln-->(31)His). In position 292, the G (A*2408) is changed to C also resulting in an amino acid replacement, the codon 98 asparagine is mutated to histidine ((98)Asn-->(98)His) in the new A*2442 allele. The second allele was determined to be A*0301. Further typing of this sample is B*1501 B*4001.

Alleles↗
PubMed2003

Novel HLA-Cw*03 allele, Cw*030303, identified by nucleotide sequencing.

In this paper we report the identification of a new HLA- Cw*03 allele in a sample that has been distributed in the International UCLA Terasaki Cell/DNA Exchange. This novel allele officially designed Cw*03033 and renumbered to Cw*030303 (2) found in cell no. 1054 from an Asian Indian donor differs from Cw*030301 by a silent substitution at codon 128, GGG-->GGA (nucleotide position 384). This new allelic variant was confirmed by several other laboratories participating in the UCLA Terasaki Cell/DNA Exchange (3).

Amino Acid Sequence↗
PubMed2001

Treatment practices for chlamydial infection in New Zealand.

AIMS: To identify prescribing and treatment practices for chlamydial infection in New Zealand. METHODS: Postal survey to doctors and nurses at all sexual health, family planning, student and youth health centres, and randomly selected general practitioners. RESULTS: There was considerable variation in treatment regimes used for chlamydial infection with few respondents treating in accordance with international guidelines regarding dose, frequency, and duration of treatment. Doxycycline (88.4%) was most commonly used to treat uncomplicated chlamydial infection in non-pregnant patients. Most respondents (70.2%) stipulated doxycycline for longer durations than the seven day regimen international guidelines recommend, with doxycycline 100 mg twice a day for ten days most frequently specified. Among the 259 respondents who would treat pregnant women with erythromycin, 51 different treatment regimens were specified, and 51.7% recorded regimens less than that recommended by international guidelines. When treating a patient presumptively, the majority of respondents tested for chlamydial infection. In contrast to other respondents, sexual health clinic staff rarely provide patients with a prescription for a patient's partner without seeing the partner. CONCLUSIONS: Standardised treatment guidelines are required for patients diagnosed with chlamydial infection. Guidelines should include recommendations for the treatment of partners, and encourage the laboratory confirmation of diagnosis.

Anti-Bacterial Agents↗
PubMed2001

Screening and diagnostic practices for chlamydia infections in New Zealand.

AIMS: To identify screening and diagnostic practices for chlamydia infection in New Zealand. METHODS: Postal survey of doctors and nurses at all sexual health, family planning, youth and student clinics, and randomly selected general practitioners (GPs). RESULTS: Most respondents recognised chlamydia infection as a cause of pelvic inflammatory disease and infertility in females, and epididymitis and non-gonococcal urethritis in males. Ectopic pregnancy and conjunctivitis were less commonly recognised by GPs and student and youth centre doctors. Sterile pyuria and arthritis were well recognised only by sexual health doctors. Female doctors were significantly more likely to recognise signs and symptoms than male doctors. GPs were less likely than other respondents to screen for chlamydia infection. Sexual health doctors and nurses were more likely to remove cervical secretions prior to taking endocervical specimens. Contact tracing was regarded as very important by only a quarter of family planning respondents, compared with over 80% of other respondents. CONCLUSIONS: While respondents recognised most signs, symptoms, and sequelae of chlamydia infection, some important features were not well recognised. Screening practices varied, and many endocervical specimens were taken incorrectly. Given the long-term health consequences and cost of chlamydia infection sequelae, screening guidelines are urgently required.

Adolescent↗
PubMed2001

Surveillance of sexually transmitted infections in New Zealand, 1998.

AIMS: To describe the surveillance and epidemiology of sexually transmitted infections (STIs) in New Zealand. METHODS: Sexual health clinics submitted STI data to the Institute of Environmental Science and Research (ESR). Infection rates were calculated by dividing the number of diagnoses by the number of total clinic visits. Because the denominator used to calculate infection rates changed in 1998, STI rates in 1998 cannot be directly compared with previous years and case numbers were used to identify recent trends. RESULTS: In 1998, genital warts was the most commonly diagnosed STI (4.7%), followed by chlamydia (3.0%) and genital herpes (1.0%). Approximately two-thirds of gonorrhoea, chlamydia and genital warts diagnoses were in people aged less than 25 years. Chlamydia rates were 7.3% in Maori, 7.1% in Pacific Island people, and 2.1% in European. Gonorrhoea rates were 1.6% in Maori, 1.9% in Pacific Island people and 0.2% in European. The number of chlamydia and gonorrhoea cases increased between 1995 and 1998. CONCLUSIONS: The reporting of data by age, sex and ethnicity has allowed a more useful evaluation of the incidence of STIs. The majority of STIs were diagnosed among young New Zealanders, and disproportionately high chlamydia and gonorrhoea infection rates were found among Maori and Pacific Island people.

Adolescent↗
PubMed2000

Household crowding a major risk factor for epidemic meningococcal disease in Auckland children.

BACKGROUND: New Zealand is in its ninth year of a serogroup B meningococcal disease epidemic with annual rates of up to 16.9 cases per 100,000. The highest incidence is in Maori and Pacific Island children in the Auckland region. We conducted a case-control study to identify potentially modifiable risk factors for this disease. METHODS: A case-control study of 202 cases of confirmed and probable meningococcal disease in Auckland children younger than 8 years of age recruited from May, 1997, to March, 1999, was undertaken. Controls (313) were recruited door-to-door by a cluster sampling method based on starting points randomly distributed in the Auckland region. They were frequency matched with the expected distribution of age and ethnicity in the meningococcal disease cases. RESULTS: With the use of a multivariate model and controlling for age, ethnicity, season and socioeconomic factors, risk of disease was strongly associated with overcrowding as measured by the number of adolescent and adult (10 years or older) household members per room [odds ratio (OR), 10.7; 95% confidence interval (CI), 3.9 to 29.5]. This would result in a doubling of risk with the addition of 2 adolescents or adults to a 6-room house. Risk of disease was also associated with analgesic use by the child, which was thought to be a marker of recent illness (OR 2.4, CI 1.5 to 4.0); number of days at substantial social gatherings (10 or more people for > 4 h; OR 1.8, CI 1.2 to 2.6); number of smokers in the household (OR 1.4, CI 1.0 to 1.8); sharing an item of food, drink or a pacifier (OR 1.6, CI 1.0 to 2.7); and preceding symptoms of a respiratory infection (cough, "cold or flu," runny nose, sneezing) in a household member (OR 1.5, CI 1.0 to 2.5). CONCLUSION: Some of these identified risk factors for meningococcal disease are modifiable. Measures to reduce overcrowding could have a marked effect on reducing the incidence of this disease in Auckland children.

Adolescent↗
PubMed1995

Identification of two major HLA-B44 subtypes and a novel B44 sequence (B*4404). Oligotyping and solid phase sequencing of polymerase chain reaction products.

PCR-based analyses were performed for the identification of HLA-B44 subgroups. Genomic DNA from six homozygous cell lines and 44 healthy individuals who had serologically tested positive for HLA-B44 was investigated for polymorphism in exons 2 and 3 of the HLA-B44 genes. Two primers were designed for specific amplification of the B*4401 allele in exon 2. None of the tested genomic DNAs, including the cell line "BAU-J" from which the sequence of B*4401 was derived, was amplified successfully using these primers, indicating that the B*4401 sequence may not be correct in position 242-244. For identification of the B*4402 and *4403 subtypes we specifically amplified the B44 gene in exon 3 using two sequence-specific primers. The PCR products, which were obtained from all B44-positive samples (n = 50) and from none of the B44-negative controls (n = 20), were subsequently hybridized with the dig-ddUTP-labeled oligonucleotides. The base substitution at position 146, as described previously for B*4401 and *4402 (C for G), could not be confirmed by oligonucleotide hybridization. In contrast, the oligonucleotide typing for G in position 146 gave positive signals in all B44-positive samples. Except for one, HLA-B44-positive DNAs from LCLs and healthy individuals could be divided into two subgroups according to the polymorphic region in position 195-197. Out of 44 unrelated individuals with B44, 27 (61%) were positive for B*4402 and 16 (36%) were positive for B*4403.(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗
PubMed1990

Immunological studies on onchocerciasis in Sierra Leone. 1. Pretreatment baseline data.

Cellular immune responses were tested in vitro using peripheral blood mononuclear cells from 203 individuals resident in an area of Sierra Leone where onchocerciasis is hyperendemic, and 32 individuals (Gambians) with no history of contact with Onchocerca volvulus. Mean reactivity to the mitogen, Concanavalin A, did not differ between these two groups, but responses to PPD were markedly lower in those with onchocerciasis. Proliferative responses to adult female O. volvulus antigen in the latter group were generally low although elevated reactivity was found in certain sub-groups. Higher responses were evident in infected 10-14 year olds, and there was an association between elevated reactivity to O. volvulus antigens and acute reactive dermatological signs, with individuals in the latter group also carrying higher dermal microfilarial loads. A sub-group presenting with lymphadenopathy showed the strongest associations of these three parameters. These results suggested the requirement for a threshold density of dermal microfilariae for induction of acute reactivity. The presence of immunosuppressive factors in soluble O. volvulus antigen was indicated by the ability to suppress, at low concentrations, the cellular responses to PPD of a proportion of individuals.

Adolescent↗
PubMed1987

Characterization of DR blank alleles by restriction fragment length polymorphism (RFLP).

Using a combination of conventional DR serology and RFLP analysis of DR beta and DQ beta, we have been able to identify two different types of DR antigens which belong so far to the DR blank group. The antigen DR-LOT is found on a haplotype A29, Bw60, Cw3, DRblank, DRw52, DQw1. The DR beta-EcoRI RFLP pattern of this haplotype is different from the patterns observed for DR1, DR2, DR3, DR4, DR5, DRw6, DR7, DRw8, DRw9, DRw10, and appears to be composed of a combination of DR2 and DRw6. The DQ beta-EcoRI pattern shows that this haplotype carries the DQw1 split DQR2.6. The second DR blank antigen which we found in a total of five individuals (three unrelated persons and two parents) on B35 positive haplotypes is characterized by a DR beta-EcoRI RFLP pattern indistinguishable from DR1 and by negative reaction with anti-DR1 sera. This antigen appears to be identical to what has been described by Cambon-Thomsen et al. (1986) and Bidwell et al. (1985) as HLA-DR-BON and DR"BR" respectively. We have demonstrated that this antigen is in strong linkage disequilibrium with the DQw1 split DQR1.

Alleles↗
PubMed1977

B- and T-cell-specific alloantigens in man.

Screening for B-cell-specific antibodies in unabsorbed pregnancy sera preselected for weak reactivity in regular HLA-A, -B, and -C screening yielded a relatively high proportion (35/81) of B-cell-specific antibodies. Most B-cell-specific antibodies react broadly, showing inclusion phenomena suggesting 'cross-reactivity' analogous to that observed in HLA-A and -B serology. In control experiments with T-cell-enriched suspensions three antisera reacted with T cells and not with B cells. These antisera are highly associated with HLA-A2 in the unrelated population and segregate with HLA haplotypes in families and with HLA-A in a family with HLA-A, B recombination, Thus it appears that the human equivalents of Ia antigens may include--in analogy to the murine Ia antigens--B cell- as well as T-cell-specific alloantigens.

Antibody Specificity↗
PubMedDate not supplied

Painful day.

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Child↗