Biomedical subjects

B Biggs

Publications and source records attributed to B Biggs.

15 recordsLinked to original sources

PubMed2004

Management systems response to improving immunization coverage in developing countries: a case study from Cambodia.

INTRODUCTION: In contrast to the initial success following the establishment of the National Immunization Program (NIP) in Cambodia in 1986, infant vaccination coverage rates against the six expanded program immunization diseases have not improved since 1995. In response, the NIP of the Ministry of Health has undertaken a series of institutional initiatives to address the problem of static or declining rates of coverage. The aim of this paper is to describe and assess management strategies undertaken by the NIP in Cambodia in support of improved immunization coverage. METHODS: Sources of information used in preparing this report include international literature, national coverage and surveillance data, government policy documentation, information generated by national strategic planning and health centre microplanning processes, a functional analysis of human resources, and data quality audits. RESULTS: The NIP has implemented planning, organizational development and human resource development responses to the problem of low coverage. These have included: integration of the nip strategic and operational plans into the health sector plan; strengthening of needs-based microplanning; establishment of a national monitoring and management support strategy; and the introduction of performance-based agreements between levels of government for improved immunization coverage. CONCLUSIONS: Our analysis of these findings, in particular of the international literature, suggests that NIP's responses have been appropriate, and that the development of NIP management systems and capacity will increase the likelihood for sustained immunization coverage gains within a reform environment of health system decentralization. In 2003, there are early signs that the reform processes undertaken by the NIP have resulted in improved immunization coverage in targeted areas, and this should place the national program in a stronger position to lift immunization coverage in 2004.

Journal Article↗

PubMed2000

Agglutinating antibodies to Toxoplasma gondii in sera from captive eastern barred bandicoots in Australia.

Toxoplasmosis is considered a severe health risk for many marsupial species. The mainland Australian population of bandicoot is endangered. Therefore, a preliminary serosurvey was conducted to evaluate exposure to Toxoplasma gondii in 57 captive eastern barred bandicoot and to estimate the possible impact of Toxoplasma on recovering populations. Five (9%) bandicoot were classified as seropositive using a modified agglutination test. Nineteen additional bandicoot (33%) were classified as serosuspect using a direct agglutination test. No bandicoot showed signs of clinical disease. Seropositive titers were IgG associated, suggesting that infections were chronic and latent. Serostatus was not associated with either sex or being wild-caught, although each seropositive bandicoot was wild-caught. Seropositive animals ranged from 1.25- to 2.5-yr-old. Computer simulations using Vortex 5.1, based on the proportion of seropositive and seronegative bandicoot in this study, indicate that mortalities from T. gondii should have little impact upon captive populations. However, the potential impact of toxoplasmosis on recovery efforts for wild, mainland bandicoot populations is not clear.

Agglutination Tests↗

PubMed1998

The retro-Mannich cleavage of delta1,delta1'-tryptophan dimers.

Under acidic conditions tryptophan sidechains crosslink to form delta1,delta1'-tryptophan dimers through a Mannich-type mechanism. Tryptophan dimers are readily cleaved at high temperatures under acidic conditions making it impossible to isolate tryptophan dimers under standard conditions of acidic protein hydrolysis. In a prescriptive sense this cleavage can be used to recover peptides that have undergone tryptophan crosslinking, although the yields drop with increasing peptide length due to competitive cleavage of the amide bonds. The best conditions for cleavage involve heating the dimeric peptides in dilute ethanolic HCl at 150 degrees C in the presence of ten equivalents of ethanedithiol.

Dimerization↗

PubMed1989

The effect of drugs on the cell cycle of Giardia intestinalis.

Flow cytometric analysis of the binucleated protozoan parasite Giardia intestinalis gave DNA histograms with a broad G1 peak and a definable G2 + M peak with twice the DNA content of G1. Twenty-four hour treatment with metronidazole arrested cell cycle progression of susceptible trophozoites in the G2 + M phase, but had no effect, even at toxic doses, on the DNA histogram of a line selected for resistance to metronidazole. Furazolidone was inhibitory to both stocks, causing an arrest in the S and G2 + M phases. Inhibitors of the mammalian cell cycle were also tested. Hydroxyurea, which blocks mammalian cells in G1/S, and razoxane, which blocks in G2 + M, arrested trophozoites in the G2 + M phase whereas colchicine and gamma-irradiation had little or no effect on the cell cycle of G. intestinalis. These results suggest that the cell cycle of G. intestinalis may be controlled in a different manner from mammalian cells.

Animals↗

PubMed1987

Comparison of a multiple puncture tuberculin test, 'Imotest', and the Mantoux test in an Australian population.

The new multiple puncture tuberculin testing device, 'Imotest', was compared to the Mantoux test (10 I.U.) in an Australian population. The tests were applied simultaneously to opposite forearms of 105 volunteers. Sixty-eight per cent of the Mantoux tests were positive compared to 39% of the 'Imotests', resulting in a false negative rate of 44% and the difference was highly significant. A further 30 volunteers were tested with a different batch of 'Imotest' and similar results were obtained. When multiple 'Imotests' were applied simultaneously to each of two subjects in a separate study, there was a wide variation of response within each subject, and positive and negative reactions occurred side by side. These results indicate that the 'Imotest' is significantly less sensitive than the Mantoux test and is unsuitable for use as a diagnostic or screening test.

Australia↗

PubMed1986

Acute HTLV-III infection. A case followed from onset to seroconversion.

An acute febrile illness with mouth ulcers and a skin rash was observed in a 37-year-old homosexual man. Acute human T-lymphotropic virus type III (HTLV-III) infection was suspected. The clinical features were documented prospectively, and striking changes in circulating T lymphocytes were demonstrated shortly after the onset of the illness. Seroconversion for HTLV-III antibody occurred between 46 and 78 days after the onset of the illness.

Acute Disease↗

PubMed1983

Reno-vascular disease in polycythaemia rubra vera.

Hypertension and polycythaemia rubra vera commonly occur in the same patient. This is regarded as coincidence and the hypertension does not respond to correction of polycythaemia. We report a case of renal artery stenosis occurring simultaneously with polycythaemia rubra vera and suggest that renovascular occlusive disease should be excluded in such patients with refractory hypertension.

Humans↗

PubMed1979