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Background: Globally, BCG vaccination varies in efficacy and has some non-specific protective effects. Previous studies comparing BCG strains have been small-scale, with few or no immunological outcomes and have compared TB-specific responses only. We aimed to evaluate both specific and non-specific immune responses to different strains of BCG within a large infant cohort and to evaluate further the relationship between BCG strain, scarring and cytokine responses., Methods: Infants from the Entebbe Mother and Baby Study (ISRCTN32849447) who received BCG-Russia, BCG-Bulgaria or BCG-Denmark at birth, were analysed by BCG strain group. At one year, interferon-gamma (IFN-γ), interleukin (IL)-5, IL-13 and IL-10 responses to mycobacteria-specific antigens (crude culture filtrate proteins and antigen 85) and non-mycobacterial stimuli (tetanus toxoid and phytohaemagglutinin) were measured using ELISA. Cytokine responses, scar frequency, BCG associated adverse event frequency and mortality rates were compared across groups, with adjustments for potential confounders., Results: Both specific and non-specific IFN-γ, IL-13 and IL-10 responses in 1341 infants differed between BCG strain groups including in response to stimulation with tetanus toxoid. BCG-Denmark immunised infants showed the highest cytokine responses. The proportion of infants who scarred differed significantly, with BCG scars occurring in 52.2%, 64.1% and 92.6% of infants immunised with BCG Russia, BCG-Bulgaria and BCG-Denmark, respectively (p<0.001). Scarred infants had higher IFN-γ and IL-13 responses to mycobacterial antigens only than infants without a scar. The BCG-Denmark group had the highest frequency of adverse events (p=0.025). Mortality differences were not significant., Conclusions: Both specific and non-specific immune responses to the BCG vaccine differ by strain. Scarring after BCG vaccination is also strain-dependent and is associated with higher IFN-γ and IL-13 responses to mycobacterial antigens. The choice of BCG strain may be an important factor and should be evaluated when testing novel vaccine strategies that employ BCG in prime-boost sequences, or as a vector for other vaccine antigens., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: Helminth infections may modulate immune responses to unrelated pathogens and allergens; these effects may commence prenatally. We addressed the hypothesis that anthelminthic treatment in pregnancy and early childhood would improve responses to immunisation and modulate disease incidence in early childhood with both beneficial and detrimental effects., Methods and Findings: A randomised, double-blind, placebo-controlled trial was conducted in Entebbe, Uganda [ISRCTN32849447]. In three independent randomisations, 2507 pregnant women were allocated to receive single-dose albendazole or placebo, and praziquantel or placebo; 2016 of their offspring were randomised to receive quarterly single-dose albendazole or placebo from age 15 months to 5 years. Primary outcomes were post-immunisation recall responses to BCG and tetanus antigens, and incidence of malaria, diarrhoea, and pneumonia; incidence of eczema was an important secondary outcome. Analysis was by intention-to-treat. Of 2345 live births, 1622 (69%) children remained in follow-up at age 5 years. 68% of mothers at enrolment, and 11% of five-year-olds, had helminth infections. Maternal hookworm and Schistosoma mansoni were effectively treated by albendazole and praziquantel, respectively; and childhood hookworm and Ascaris by quarterly albendazole. Incidence rates of malaria, diarrhoea, pneumonia, and eczema were 34, 65, 10 and 5 per 100 py, respectively. Albendazole during pregnancy caused an increased rate of eczema in the children (HR 1.58 (95% CI 1.15-2.17), p = 0.005). Quarterly albendazole during childhood was associated with reduced incidence of clinical malaria (HR 0.85 (95% CI 0.73-0.98), p = 0.03). There were no consistent effects of the interventions on any other outcome., Conclusions: Routine use of albendazole in pregnancy may not always be beneficial, even in tropical developing countries. By contrast, regular albendazole treatment in preschool children may have an additional benefit for malaria control where helminths and malaria are co-endemic. Given the low helminth prevalence in our children, the effect of albendazole on malaria is likely to be direct., Trial Registration: Current Controlled Trials ISRCTN32849447.

Background: Children with latent tuberculosis infection (LTBI) represent a huge reservoir for future disease. We wished to determine Mycobacterium tuberculosis (M.tb) infection prevalence among BCG-immunised five-year-old children in Entebbe, Uganda, but there are limited data on the performance of immunoassays for diagnosis of tuberculosis infection in children in endemic settings. We therefore evaluated agreement between a commercial interferon gamma release assay (T-SPOT.TB) and the tuberculin skin test (TST; 2 units RT-23 tuberculin; positive defined as diameter ≥10 mm), along with the reproducibility of T-SPOT.TB on short-term follow-up, in this population., Methodology/principal Findings: We recruited 907 children of which 56 were household contacts of TB patients. They were tested with T-SPOT.TB at age five years and then re-examined with T-SPOT.TB (n = 405) and TST (n = 319) approximately three weeks later. The principal outcome measures were T-SPOT.TB and TST positivity. At five years, 88 (9.7%) children tested positive by T-SPOT.TB. More than half of those that were T-SPOT.TB positive at five years were negative at follow-up, whereas 96% of baseline negatives were consistently negative. We observed somewhat better agreement between initial and follow-up T-SPOT.TB results among household TB contacts (κ = 0.77) than among non-contacts (κ = 0.39). Agreement between T-SPOT.TB and TST was weak (κ = 0.28 and κ = 0.40 for T-SPOT.TB at 5 years and follow-up, respectively). Of 28 children who were positive on both T-SPOT.TB tests, 14 (50%) had a negative TST. Analysis of spot counts showed high levels of instability in responses between baseline and follow-up, indicating variability in circulating numbers of T cells specific for certain M.tb antigens., Conclusions/significance: We found that T-SPOT.TB positives are unstable over a three-week follow-up interval, and that TST compares poorly with T-SPOT.TB, making the categorisation of children as TB-infected or TB-uninfected difficult. Existing tools for the diagnosis of TB infection are unsatisfactory in determining infection among children in this setting.

The role of T-cells in immunity against Mycobacterium tuberculosis (M. tuberculosis) infection has been extensively studied, however, that of B-cells still remains comparatively unexplored. In this study, we determined the presence and frequencies of mycobacteria-specific memory B-cells (MBCs) in peripheral blood from clinically healthy, Bacillus Calmette Guerin (BCG) vaccinated (n = 79) and unvaccinated (n = 14) donors. Purified protein derivative (PPD)-specific MBCs were present in most donors (both vaccinated and unvaccinated) but their frequencies were significantly higher in vaccinated than in unvaccinated donors. MBCs specific for other mycobacterial antigens [antigen-85A (Ag85A), antigen-85B (Ag85B), 6 kDalton early secretory antigenic target (ESAT-6) and the 10 kDalton-culture filtrate protein (CFP-10)] were less prevalent than those recognising PPD. Furthermore, PPD-specific MBCs were detected in BCG vaccinated donors without ESAT-6 and CFP-10 specific responses. Together, these results indicate that BCG vaccination induces long-lived MBC responses. Similar patterns of response were seen when we examined mycobacteria-specific antibody and T-cell responses in these donors. Our data show for the first time that BCG vaccination elicits long-lived mycobacteria-specific MBC responses in healthy individuals, suggesting a more substantial role of B-cells in the response to BCG and other mycobacterial infections than previously thought.

Background: Although HIV testing and counseling (HTC) uptake has increased dramatically in Africa, facility-based services are unlikely to ever meet ongoing need to the full. A major constraint in scaling up community and home-based HTC services is the unacceptability of receiving HTC from a provider known personally to prospective clients. We investigated the potential of supervised oral HIV self-testing from this perspective., Methods and Findings: Adult members of 60 households and 72 members of community peer groups in urban Blantyre, Malawi, were selected using population-weighted random cluster sampling. Participants were offered self-testing plus confirmatory HTC (parallel testing with two rapid finger-prick blood tests), standard HTC alone, or no testing. 283 (95.6%) of 298 selected adults participated, including 136 (48.0%) men. 175 (61.8%) had previously tested (19 known HIV positive), although only 64 (21.5%) within the last year. HIV prevalence was 18.5%. Among 260 (91.9%) who opted to self-test after brief demonstration and illustrated instructions, accuracy was 99.2% (two false negatives). Although 98.5% rated the test "not hard at all to do," 10.0% made minor procedural errors, and 10.0% required extra help. Most participants indicated willingness to accept self-test kits, but not HTC, from a neighbor (acceptability 94.5% versus 46.8%, p = 0.001)., Conclusions: Oral supervised self-testing was highly acceptable and accurate, although minor errors and need for supervisory support were common. This novel option has potential for high uptake at local community level if it can be supervised and safely linked to counseling and care.

In 1994 and 2002, respectively, the World Health Organisation proposed that treatment for hookworm and schistosomiasis could be provided during pregnancy. It was hoped that this might have benefits for maternal anaemia, fetal growth and perinatal mortality; a beneficial effect on the infant response to immunisation was also hypothesised. Three trials have now been conducted. Two have examined the effects of benzimidazoles; one (the Entebbe Mother and Baby Study) the effects of albendazole and praziquantel. All three were conducted in settings of high prevalence but low intensity helminth infection. Results suggest that, in such settings and given adequate provision of haematinics, the benefit of routine anthelminthics during pregnancy for maternal anaemia may be small; none of the other expected benefits has yet been demonstrated. The Entebbe Mother and Baby Study found a significant adverse effect of albendazole on the incidence of infantile eczema in the whole study population, and of praziquantel on the incidence of eczema among infants of mothers with Schistosoma mansoni. Further studies are required in settings that differ in helminth species and infection intensities. Further research is required to determine whether increased rates of infantile eczema translate to long-term susceptibility to allergy, and to explore the underlying mechanisms of these effects. The risks and benefits of routine anthelminthic treatment in antenatal clinics may need to be reconsidered.

Unlabelled: To describe how, through a DSS in a rural area of The Gambia, it has been possible to measure substantial reductions in child mortality rates and how we investigated whether the decline paralleled the registered fall in malaria incidence in the country., Methods: Demographic surveillance data spanning 19.5 years (1 April 1989-30 September 2008) from 42 villages around the town of Farafenni, The Gambia, were used to estimate childhood mortality rates for neonatal, infant, child (1-4 years) and under-5 age groups. Data were presented in five a priori defined time periods, and annual rates per 1000 live births were derived from Kaplan-Meier survival probabilities., Results: From 1989-1992 to 2004-2008, under-5 mortality declined by 56% (95% CI: 48-63%), from 165 (95% CI: 151-181) per 1000 live births to 74 (95% CI: 65-84) per 1000 live births. In 1- to 4-year-olds, mortality during the period 2004-2008 was 69% (95% CI: 60-76%) less than in 1989-1992. The corresponding mortality decline in infants was 39% (95% CI: 23-52%); in neonates, it was 38% (95% CI: 13-66%). The derived annual under-5 mortality rates declined from 159 per 1000 live births in 1990 to 45 per 1000 live births in 2008, thus implying an attainment of MDG4 seven years in advance of the target year of 2015., Conclusion: Achieving MDG4 is possible in poor, rural areas of Africa through widespread deployment of relatively simple measures that improve child survival, such as immunisation and effective malaria control., (© 2011 Blackwell Publishing Ltd.)

Background: Offspring of women with schistosomiasis may exhibit immune responsiveness to schistosomes due to in utero sensitisation or trans-placental transfer of antibodies. Praziquantel treatment during pregnancy boosts maternal immune responses to schistosome antigens and reduces worm burden. Effects of praziquantel treatment during pregnancy on responses among offspring are unknown., Methods: In a trial of anthelminthic treatment during pregnancy in Uganda (ISRCTN32849447; http://www.controlled-trials.com/ISRCTN32849447/elliott), offspring of women with Schistosoma mansoni were examined for cytokine and antibody responses to schistosome worm (SWA) and egg (SEA) antigen, in cord blood and at age one year. Relationships to maternal responses and pre-treatment infection intensities were examined, and responses were compared between the offspring of women who did, or did not receive praziquantel treatment during pregnancy., Results: Of 388 S. mansoni-infected women studied, samples were obtained at age one year from 215 of their infants. Stool examination for S. mansoni eggs was negative for all infants. Cord and infant samples were characterised by very low cytokine production in response to schistosome antigens with the exception of cord IL-10 responses, which were substantial. Cord and infant cytokine responses showed no association with maternal responses. As expected, cord blood levels of immunoglobulin (Ig) G to SWA and SEA were high and correlated with maternal antibodies. However, by age one year IgG levels had waned and were hardly detectable. Praziquantel treatment during pregnancy showed no effect on cytokine responses or antibodies levels to SWA or SEA either in cord blood or at age one year, except for IgG1 to SWA, which was elevated in infants of treated mothers, reflecting maternal levels. There was some evidence that maternal infection intensity was positively associated with cord blood IL-5 and IL-13 responses to SWA, and IL-5 responses to SEA, and that this association was modified by treatment with praziquantel., Conclusions: Despite strong effects on maternal infection intensity and maternal immune responses, praziquantel treatment of infected women during pregnancy had no effect on anti-schistosome immune responses among offspring by age one year. Whether the treatment will impact upon the offspring's responses on exposure to primary schistosome infection remains to be elucidated., Trial Registration: ISRCTN: ISRCTN32849447.

Objectives: Recurrent or persistent coinfections may increase HIV viral load and, consequently, risk of HIV transmission, thus increasing HIV incidence. We evaluated the association between malaria, herpes simplex virus type 2 (HSV-2) and tuberculosis (TB) coinfections and their treatment on HIV viral load., Design: Systematic review and meta-analysis of the association of malaria, HSV-2 and TB coinfections and their treatment with HIV viral load., Methods: PubMed and Embase databases were searched to 10 February 2010 for studies in adults that reported HIV plasma and/or genital viral load by coinfection status or treatment. Meta-analyses were conducted using random-effects models., Results: Forty-five eligible articles were identified (six malaria, 20 HSV-2 and 19 TB). There was strong evidence of increased HIV viral load with acute malaria [0.67 log(10) copies/ml, 95% confidence interval (CI) 0.15-1.19] and decreased viral load following treatment (-0.37 log(10) copies/ml, 95% CI -0.70 to -0.04). Similarly, HSV-2 infection was associated with increased HIV viral load (0.18 log(10) copies/ml, 95% CI 0.01-0.34), which decreased with HSV suppressive therapy (-0.28 log(10) copies/ml, 95% CI -0.36 to -0.19). Active TB was associated with increased HIV viral load (0.40 log(10) copies/ml, 95% CI 0.13-0.67), but there was no association between TB treatment and viral load reduction (log(10) copies/ml -0.02, 95% CI -0.19 to 0.15)., Conclusion: Coinfections may increase HIV viral load in populations where they are prevalent, thereby facilitating HIV transmission. These effects may be reversed with treatment. However, to limit HIV trajectory and optimize positive prevention for HIV-infected individuals pre-antiretroviral therapy, we must better understand the mechanisms responsible for augmented viral load and the magnitude of viral load reduction required, and retune treatment regimens accordingly.

Background: Allergy is commoner in developed than in developing countries. Chronic worm infections show inverse associations with allergy, and prenatal exposures may be critical to allergy risk., Objective: To determine whether anthelminthic treatment during pregnancy increases the risk of allergy in infancy., Methods: A randomised, double-blind, placebo-controlled trial on treatment in pregnancy with albendazole versus placebo and praziquantel versus placebo was conducted in Uganda, with a 2 × 2 factorial design; 2507 women were enrolled; infants' allergy events were recorded prospectively. The main outcome was doctor-diagnosed infantile eczema., Results: Worms were detected in 68% of women before treatment. Doctor-diagnosed infantile eczema incidence was 10.4/100 infant years. Maternal albendazole treatment was associated with a significantly increased risk of eczema [Cox HR (95% CI), p: 1.82 (1.26-2.64), 0.002]; this effect was slightly stronger among infants whose mothers had no albendazole-susceptible worms than among infants whose mothers had such worms, although this difference was not statistically significant. Praziquantel showed no effect overall but was associated with increased risk among infants of mothers with Schistosoma mansoni [2.65 (1.16-6.08), interaction p = 0.02]. In a sample of infants, skin prick test reactivity and allergen-specific IgE were both associated with doctor-diagnosed eczema, indicating atopic aetiology. Albendazole was also strongly associated with reported recurrent wheeze [1.58 (1.13-2.22), 0.008]; praziquantel showed no effect., Conclusions: The detrimental effects of treatment suggest that exposure to maternal worm infections in utero may protect against eczema and wheeze in infancy. The results for albendazole are also consistent with a direct drug effect. Further studies are required to investigate mechanisms of these effects, possible benefits of worms or worm products in primary prevention of allergy, and the possibility that routine deworming during pregnancy may promote allergic disease in the offspring., (© 2011 John Wiley & Sons A/S.)

Background: Individual malaria interventions provide only partial protection in most epidemiological situations. Thus, there is a need to investigate whether combining interventions provides added benefit in reducing mortality and morbidity from malaria. The potential benefits of combining IPT in children (IPTc) with home management of malaria (HMM) was investigated., Methods: During the 2008 malaria transmission season, 1,277 children under five years of age resident in villages within the rural Farafenni demographic surveillance system (DSS) in North Bank Region, The Gambia were randomized to receive monthly IPTc with a single dose of sulphadoxine/pyrimethamine (SP) plus three doses of amodiaquine (AQ) or SP and AQ placebos given by village health workers (VHWs) on three occasions during the months of September, October and November, in a double-blind trial. Children in all study villages who developed an acute febrile illness suggestive of malaria were treated by VHWs who had been taught how to manage malaria with artemether-lumefantrine (Coartem™). The primary aims of the project were to determine whether IPTc added significant benefit to HMM and whether VHWs could effectively combine the delivery of both interventions., Results: The incidence of clinical attacks of malaria was very low in both study groups. The incidence rate of malaria in children who received IPTc was 0.44 clinical attacks per 1,000 child months at risk while that for control children was 1.32 per 1,000 child months at risk, a protective efficacy of 66% (95% CI -23% to 96%; p = 0.35). The mean (standard deviation) haemoglobin concentration at the end of the malaria transmission season was similar in the two treatment groups: 10.2 (1.6) g/dL in the IPTc group compared to 10.3 (1.5) g/dL in the placebo group. Coverage with IPTc was high, with 94% of children receiving all three treatments during the study period., Conclusion: Due to the very low incidence of malaria, no firm conclusion can be drawn on the added benefit of IPTc in preventing clinical episodes of malaria among children who had access to HMM in The Gambia. However, the study showed that VHWs can successfully combine provision of HMM with provision of IPTc.

Background: HIV/AIDS related stigma is a major barrier to uptake of HIV testing and counselling (HTC). We assessed the extent of stigmatising attitudes expressed by participants offered community-based HTC, and their anticipated stigma from others to assess relationship with HIV test uptake. From these data, we constructed a brief stigma scale for use around the time of HIV testing., Methods and Findings: Adult members of 60 households in urban Blantyre, Malawi, were selected using population-weighted random cluster sampling and offered HTC with the option to self-test before confirmatory HTC. Prior to HTC a 15-item HIV stigma questionnaire was administered. We used association testing and principal components analysis (PCA) to construct a scale measure of stigma. Of 226 adults invited to participate, 216 (95.6%) completed questionnaires and 198/216 (91.7%) opted to undergo HTC (all self-tested). Stigmatising attitudes were uncommon, but anticipated stigma was common, especially fearing verbal abuse (22%) or being abandoned by their partner (11%). Three questions showed little association or consistency with the remaining 12 stigma questions and were not included in the final scale. For the 12-question final scale, Cronbach's alpha was 0.75. Level of stigma was not associated with previously having tested for HIV (p = 0.318) or agreeing to HTC (p = 0.379), but was associated with expressed worry about being or becoming HIV infected (p = 0.003)., Conclusions: Anticipated stigma prior to HTC was common among both men and women. However, the high uptake of HTC suggests that this did not translate into reluctance to accept community-based testing. We constructed a brief scale to measure stigma at the time of HIV testing that could rapidly identify individuals requiring additional support following diagnosis and monitor the impact of increasing availability of community-based HTC on prevalence of stigma.

Background: Helminth infections affect the human immune response. We investigated whether prenatal exposure to and treatment of maternal helminth infections affects development of an infant's immune response to immunisations and unrelated infections., Methods: In this randomised, double-blind, placebo-controlled trial, we enrolled 2507 women in the second or third trimester of pregnancy who were planning to deliver in Entebbe General Hospital, Entebbe, Uganda. With a computer-generated random number sequence in blocks of 100, we assigned patients to 440 mg albendazole and 40 mg/kg praziquantel (n=628), 440 mg albendazole and a praziquantel-matching placebo (n=625), 40 mg/kg praziquantel and an albendazole-matching placebo (n=626), or an albendazole-matching placebo and praziquantel-matching placebo (n=628). All participants and hospital staff were masked to allocation. Primary outcomes were immune response at age 1 year to BCG, tetanus, and measles immunisation; incidence of infectious diseases during infancy; and vertical HIV transmission. Analysis was by intention-to-treat. This trial is registered, number ISRCTN32849447., Findings: Data were available at delivery for 2356 women, with 2345 livebirths; 2115 (90%) of liveborn infants remained in follow-up at 1 year of age. Neither albendazole nor praziquantel treatments affected infant response to BCG, tetanus, or measles immunisation. However, in infants of mothers with hookworm infection, albendazole treatment reduced interleukin-5 (geometric mean ratio 0·50, 95% CI 0·30-0·81, interaction p=0·02) and interleukin-13 (0·52, 0·34-0·82, 0·0005) response to tetanus toxoid. The rate per 100 person-years of malaria was 40·9 (95% CI 38·3-43·7), of diarrhoea was 134·1 (129·2-139·2), and of pneumonia was 22·3 (20·4-24·4). We noted no effect on infectious disease incidence for albendazole treatment (malaria [hazard ratio 0·95, 95% CI 0·79-1.14], diarrhoea [1·06, 0·96-1·16], pneumonia [1·11, 0·90-1·38]) or praziquantel treatment (malaria [1·00, 0·84-1·20], diarrhoea [1·07, 0·98-1·18], pneumonia [1·00, 0·80-1·24]). In HIV-exposed infants, 39 (18%) were infected at 6 weeks; vertical transmission was not associated with albendazole (odds ratio 0·70, 95% CI 0·35-1·42) or praziquantel (0·60, 0·29-1·23) treatment., Interpretation: These results do not accord with the recently advocated policy of routine antenatal anthelmintic treatment, and the value of such a policy may need to be reviewed., Funding: Wellcome Trust., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Some vaccines show poor efficacy in tropical countries. Within a birth cohort in Uganda, we investigated factors that might influence responses to BCG and tetanus immunisation. Whole blood assay responses to crude culture filtrate proteins of Mycobacterium tuberculosis (cCFP)) and tetanus toxoid (TT) were examined among 1506 and 1433 one-year-olds, respectively. Maternal Mansonella perstans infection was associated with higher interleukin (IL)-10 responses to both immunogens but no reduction in gamma interferon (IFN-γ), IL-5 and IL-13 responses; other maternal helminth infections showed little effect. Tetanus immunisation during pregnancy was associated with higher infant responses to TT; maternal BCG scar (from past immunisation) with lower infant IL-5 and IL-13 responses to cCFP. IFN-γ, IL-5 and IL-13 to TT were reduced in HIV-exposed-uninfected infants; infant malaria and HIV were associated with lower IFN-γ, IL-5 and IL-13 responses to both immunogens. We conclude that maternal helminth infections are unlikely to explain poor vaccine efficacy in the tropics. Effects of maternal immunisation on infant responses to vaccines should be explored. Prevention of infant malaria and HIV could contribute to effectiveness of immunisation programmes., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

To assess whether DNA repair gene variants influence the clinical behaviour of lung cancer we examined the impact of a comprehensive panel of 109 non-synonymous single-nucleotide polymorphisms (nsSNPs) in 50 DNA repair genes on overall survival (OS) in 700 lung cancer patients. Fifteen nsSNPs were associated with OS, significantly greater than that expected (P = 0.04). SNPs associated with prognosis mapped primarily to two repair pathways--nucleotide excision repair (NER): ERCC5 D1104H (P = 0.004); ERCC6 G399D (P = 0.023), ERCC6 Q1413R (P = 0.025), POLE (P = 0.014) and base excision repair: APEX1 D148E (P = 0.028); EXO1 E670G (P = 0.007); POLB P242R (P = 0.018). An increasing number of variant alleles in EXO1 was associated with a poorer prognosis [hazard ratio (HR) = 1.24; P = 0.0009]. A role for variation in NER and BRCA2/FA pathway genes as determinants of OS was provided by an analysis restricted to the 456 patients treated with platinum-based agents. Our data indicate that the pathway-based approach has the potential to generate prognostic markers of clinical outcome.

The prognostic significance of the Arg72Pro polymorphism of the p53 tumour suppressor gene in cancer is controversial. To determine whether Arg72Pro is a marker for lung cancer prognosis we genotyped 619 female lung cancer patients with incident disease and examined the relationship between genotype and overall survival (OS). Nonparametric tests provided no evidence for a relationship between SNP genotype and OS (P-values 0.131, 0.161, and 0.156 for log rank, Wilcoxon and Fleming-Harrington test statistics, respectively). Under the Cox proportional hazards model the HRs associated with Arg/Pro, Pro/Pro and Pro-carrier status were: 0.98 (95%CI: 0.79-1.22), 0.76 (95%CI: 0.51-1.15) and 0.93 (95%CI: 0.76-1.15), respectively. Despite employing a comprehensive set of statistical tests including those sensitive to the detection of differences in early survival our data provide little evidence to support the tenet that the p53 Arg72Pro polymorphism is a clinically useful prognostic marker for lung cancer.

Functional nonsynonymous single-nucleotide polymorphisms (nsSNPs) of folate metabolism genes can influence the methylation of tumour suppressor genes, thereby potentially impacting on tumour behaviour. To investigate whether such polymorphisms influence lung cancer survival, we genotyped 14 nsSNPs mapping to methylene-tetrahydrofolate reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR); DNA methyltransferase (DNMT2), methylenetetrahydrofolate dehydrogenase (MTHFD1) and methenyltetrahydrofolate synthetase (MTHFS) in 619 Caucasian women with incident disease, 465 with non-small cell (NSCLC) and 154 with small cell lung cancer (SCLC). The most significant association detected was with MTHFS Thr202Ala, with carriers of variant alleles having a worse prognosis (hazard ratio (HR)=1.49; 95% confidence interval: 1.14-1.94). Associations were also detected between overall survival (OS) in SCLC and homozygosity for MTHFR 222Val (HR=1.92; 1.03-3.58) and between OS from NSCLC and MTRR 175Leu carrier status (HR=1.36; 1.06-1.75). While there is evidence that variation in the folate metabolism genes may influence prognosis from lung cancer, current data are insufficiently robust to distinguish individual patient outcome.

The Gly388Arg polymorphism in the fibroblast growth factor receptor 4 (FGFR4) gene has been reported to influence prognosis in a wide variety of cancer types. To determine whether Gly388Arg is a marker for lung cancer prognosis, we genotyped 619 lung cancer patients with incident disease and examined the relationship between genotype and overall survival. While we employed a comprehensive set of statistical tests, including those sensitive to the detection of differences in early survival, our data provide little evidence to support the tenet that the FGFR4 Gly388Arg polymorphism is a clinically useful marker for lung cancer prognosis.

Low-penetrance alleles are likely to contribute to inherited susceptibility to many complex traits. Such alleles will rarely generate multiple-case families and are therefore difficult or impossible to identify through genetic linkage analyses. The search for low-penetrance alleles has therefore centred on comparing the frequencies of specific alleles in cases and controls via an association study. With recent improvements in genotyping technology and cost, and the completion of the HapMap Project, the long-predicted era of whole-genome association studies is now upon us, with several large-scale studies underway. Such studies require the simultaneous performance of a large number of statistical tests, with the result that power to detect association is in short supply, particularly if the disease allele is rare. One strategy to increase the power of an association study is to enrich cases for genetic predisposition; for this purpose, studies based on familial cases have attracted considerable interest. Using cancer as an example of a complex trait, we show that this approach greatly increases the power to detect association under a range of modes of inheritance, relative risks, and allele frequencies, but is especially efficient for detection of rare alleles.

To identify low penetrance susceptibility alleles for colorectal cancer (CRC), we genotyped 1467 non-synonymous SNPs mapping to 871 candidate cancer genes in 2575 cases and 2707 controls. nsSNP selection was biased towards those predicted to be functionally deleterious. One SNP AKAP9 M463I remained significantly associated with CRC risk after stringent adjustment for multiple testing. Further SNPs associated with CRC risk included several previously reported to be associated with cancer risk including ATM F858L [OR=1.48; 95% confidence interval (CI): 1.06-2.07] and P1054R (OR=1.42; 95% CI: 1.14-1.77) and MTHFR A222V (OR=0.82; 95% CI: 0.69-0.97). To validate associations, we performed a kin-cohort analysis on the 14 704 first-degree relatives of cases for each SNP associated at the 5% level in the case-control analysis employing the marginal maximum likelihood method to infer genotypes of relatives. Our observations support the hypothesis that inherited predisposition to CRC is in part mediated through polymorphic variation and identify a number of SNPs defining inter-individual susceptibility. We have made data from this analysis publicly available at http://www.icr.ac.uk/research/research&#95;sections/cancer&#95;genetics/cancer&#95;genetics&#95;teams/molecular&#95;and&#95;population&#95;genetics/software&#95;and&#95;databases/index.shtml in order to facilitate the identification of low penetrance CRC susceptibility alleles through pooled analyses.

Recently, homozygosity for T91A single-nucleotide polymorphism (SNP) in the serine/threonine kinase (STK15) gene, which generates the substitution F31I has been proposed to increase the risk of a number of tumours including colorectal cancer (CRC). To further evaluate the relationship between STK15 F31I and risk of CRC, we genotyped 2558 CRC cases and 2680 controls for this polymorphism. We found no evidence that homozygosity for the STK15 31I genotype confers an increased risk of CRC (odds ratio=0.95, 95% confidence interval (CI): 0.74-1.24). We also conducted a kin-cohort analysis to assess risk among first-degree relatives of the CRC cases. The hazard ratio for I/I homozygotes compared to F/F homozygotes was 1.65 (95% CI: 0.39-3.17). A meta-analysis of our case-control data and three previous studies also provided no evidence of an elevated risk of CRC associated with homozygosity. These data provide no support for the hypothesis that sequence variation in STK15 defined by SNP F31I per se confers an elevated risk of CRC.

We conducted a large-scale association study to identify low-penetrance susceptibility alleles for chronic lymphocytic leukemia (CLL), analyzing 992 patients and 2707 healthy controls. To increase the likelihood of identifying disease-causing alleles we genotyped 1467 coding nonsynonymous single nucleotide polymorphisms (nsSNPs) in 865 candidate cancer genes, biasing nsSNP selection toward those predicted to be deleterious. Preeminent associations were identified in SNPs mapping to genes pivotal in the DNA damage-response and cell-cycle pathways, including ATM F858L (odds ratio [OR] = 2.28, P < .0001) and P1054R (OR = 1.68, P = .0006), CHEK2 I157T (OR = 14.83, P = .0008), BRCA2 N372H (OR = 1.45, P = .0032), and BUB1B Q349R (OR = 1.42, P = .0038). Our findings implicate variants in the ATM-BRCA2-CHEK2 DNA damage-response axis with risk of CLL.

We conducted a large-scale genome-wide association study in UK Caucasians to identify susceptibility alleles for lung cancer, analyzing 1529 cases and 2707 controls. To increase the likelihood of identifying disease-causing alleles, we genotyped 1476 nonsynonymous single nucleotide polymorphisms (nsSNPs) in 871 candidate cancer genes, biasing SNP selection toward those predicted to be deleterious. Statistically significant associations were identified for 64 nsSNPs, generating a genome-wide significance level of P=0.002. Eleven of the 64 SNPs mapped to genes encoding pivotal components of the growth hormone/insulin-like growth factor (GH-IGF) pathway, including CAMKK1 E375G (OR=1.37, P=5.4x10(-5)), AKAP9 M463I (OR=1.32, P=1.0x10(-4)) and GHR P495T (OR=12.98, P=0.0019). Significant associations were also detected for SNPs within genes in the DNA damage-response pathway, including BRCA2 K3326X (OR=1.72, P=0.0075) and XRCC4 I137T (OR=1.31, P=0.0205). Our study provides evidence that inherited predisposition to lung cancer is in part mediated through low-penetrance alleles and specifically identifies variants in GH-IGF and DNA damage-response pathways with risk of lung cancer.

Nonsynonymous single nucleotide polymorphisms (nsSNP) have the potential to affect the structure or function of expressed proteins and are, therefore, likely to represent modifiers of inherited susceptibility. We have classified and catalogued the predicted functionality of nsSNPs in genes relevant to the biology of cancer to facilitate sequence-based association studies. Candidate genes were identified using targeted search terms and pathways to interrogate the Gene Ontology Consortium database, Kyoto Encyclopedia of Genes and Genomes database, Iobion's Interaction Explorer PathwayAssist Program, National Center for Biotechnology Information Entrez Gene database, and CancerGene database. A total of 9,537 validated nsSNPs located within annotated genes were retrieved from National Center for Biotechnology Information dbSNP Build 123. Filtering this list and linking it to 7,080 candidate genes yielded 3,666 validated nsSNPs with minor allele frequencies > or =0.01 in Caucasian populations. The functional effect of nsSNPs in genes with a single mRNA transcript was predicted using three computational tools-Grantham matrix, Polymorphism Phenotyping, and Sorting Intolerant from Tolerant algorithms. The resultant pool of 3,009 fully annotated nsSNPs is accessible from the Predicted Impact of Coding SNPs database at http://www.icr.ac.uk/cancgen/molgen/MolPopGen&#95;PICS&#95;database.htm. Predicted Impact of Coding SNPs is an ongoing project that will continue to curate and release data on the putative functionality of coding SNPs.

Outside the context of hereditary deficiencies of complement and IgA, Mendelian inherited predisposition to small vessel lymphocytic vasculitis (SVLV) has rarely been documented. Here we report a large, multigenerational family segregating symmetrical cutaneous SVLV affecting the cheeks, thighs and hands. In all affected family members the disease presented in early infancy and there was no evidence for an association with systemic disease. Skin biopsy of lesions showed a lymphocytic vasculitis with red blood cell extravasation. Complementary studies, with extensive investigation focused on dysfunction of the immunological system were negative. The pattern of inheritance of SVLV in the family was compatible with an autosomal dominantly acting disease gene with incomplete penetrance. To localize the disease causing gene in the family a genome-wide linkage search was conducted using a high-density SNP array. Haplotype construction and analysis of recombination events permitted the minimal interval defining the disease locus to be refined to a 4.7 Mb region on chromosome 6q26-q27. The genes CCR6 and GPR31, which map to the linked region represent plausible candidates for the disease on the basis of their biological function. Extensive screening of both genes by mutational analysis failed to identify a deleterious mutation in the family.

Chronic lymphocytic leukemia (CLL) and other B-cell lymphoproliferative disorders (LPDs) show clear evidence of familial aggregation, but the inherited basis is largely unknown. To identify a susceptibility gene for CLL, we conducted a genomewide linkage analysis of 115 pedigrees, using a high-density single-nucleotide polymorphism (SNP) array containing 11,560 markers. Multipoint linkage analyses were undertaken using both nonparametric (model-free) and parametric (model-based) methods. Our results confirm that the presence of high linkage disequilibrium (LD) between SNP markers can lead to inflated nonparametric linkage (NPL) and LOD scores. After the removal of high-LD SNPs, we obtained a maximum NPL of 3.14 (P=.0008) on chromosome 11p11. The same genomic position also yielded the highest multipoint heterogeneity LOD (HLOD) score under both dominant (HLOD 1.95) and recessive (HLOD 2.78) models. In addition, four other chromosomal positions (5q22-23, 6p22, 10q25, and 14q32) displayed HLOD scores >1.15 (which corresponds to a nominal P value <.01). None of the regions coincided with areas of common chromosomal abnormalities frequently observed for CLL. These findings strengthen the argument for an inherited predisposition to CLL and related B-cell LPDs.

Summary: SNPLINK is a Perl script that performs full genome linkage analysis of high-density single nucleotide polymorphism (SNP) marker sets. The presence of linkage disequilibrium (LD) between closely spaced SNP markers can falsely inflate linkage statistics. SNPLINK removes LD from the marker sets in an automated fashion before carrying out linkage analysis. SNPLINK can compute both parametric and non-parametric statistics, utilizing the freely available Allegro and Merlin software. Graphical outputs of whole genome multipoint linkage statistics are provided allowing comparison of results before and after the removal of LD.

This study compares community-based managed forests under different purposes of management, namely, state-driven "conservation" or community-designed utilization in two villages located in the Sopsai watershed, Nan Province, northern Thailand. The forest health under different intensity of uses is assessed in association with the collective behaviors and long-term purposes embedded in village social-cultural context. The study found no significant differences in forest succession and proportion in diameter at 1.3 m (dbh) class and height-class distribution of the forest under different use intensity. The forest for utilization also showed higher density and basal area of the local preferred species than the "conservation" forest. In the utilization forest, we also found a higher number of multipurpose and preferred species than in the "conservation" forest, which actually responded to the needs of the community in the long term to have more wood products (both firewood and timbers). The community-based forest management (CBFM) for utilization can also lead to natural regeneration and biodiversity similar to "conservation" forests. Through CBFM, forest resources can be managed to maintain the healthy condition under different intensities and respond to both community needs and external expectation. The findings also emphasize the importance of recognizing community needs and management objectives in watershed restoration and improving the productivity of forests under collective management.

This study assessed changes in forest cover in a mountain watershed in central Nepal between 1976 and 2000 by comparing classified satellite images coupled by GIS analyses, and examined the association of forest change with major physiographic, economic, and local forest governance parameters. The results showed an increase in forested area (forest plus shrublands) by 7.6% during 1976-2000. Forest dynamism (changes including improvement, deterioration, gain, and loss) was highest in low-elevation, south-facing and less-steep slopes that were closer to roads. Proportionately the highest net improvement and gain to forested area also took place in those locations. Forest degradation occurred at twice the rate of improvement in high elevation areas (> 2300 m). Forests located in urban and semiurban areas (i.e., a market-oriented economy) experienced a proportionately higher amount of net improvement and gain than forests in rural areas (i.e., a subsistence economy). Among the three governance arrangements, proportionately the highest net improvement and gain took place in semigovernment forests (forested area legally under the forest department but with de facto control and claim of ownership by local communities and/or municipality) followed by formalized community forests (including leasehold). Government forests, which were mostly found in the southern high mountains and had virtually open access, remained relatively stable during the study period. Over 50% of the watershed forests have not come under community-based management despite favorable policy and more than two decades of government intervention with continuous donor support. The findings indicate that the present "one size fits all" approach of community forest handover policy in Nepal needs rethinking to accommodate biophysical and socioeconomic variations across the country.

Land-use planning using geographic information systems (GIS) commonly emphasizes biophysical spatial data; however planning can be improved by integrating spatial sets of socioeconomic data into the GIS. As an example, we compared a traditional GIS-aided forestry planning protocol that considered only biophysical suitability, with an integrated GIS-aided approach that incorporated both biophysical and socioeconomic suitability. The analyses were conducted for the planning of plantation investments in the Kyaukpadaung Township in the dry zone of central Myanmar. The traditional approach used three biophysical layers for suitability: land use, slope, and accessibility. In contrast, the integrated GIS approach included biophysical suitability data, perceptions and preferences of local villagers towards forestry (social suitability), and quantitative socioeconomic data. The results indicated that the integrated approach provided two principal benefits over the traditional method. First, the integrated method resulted in a more precise idea of suitable sites for plantation investment that could benefit more rural people and also lead to greater investment efficiency. Second, incorporating social preference into the GIS takes into account the crucial element of social capital (viz., social preference), which should lead to higher levels of community acceptance of plantation projects because those plantations would be established on socially suitable land. A second GIS exercise showed how conservation investment decisions could be informed using the integrated method. The results of this study support the idea that GIS-aided planning activities can be enhanced through the incorporation of social data into the analysis. When applicable, spatial data collection efforts for GIS-based planning exercises should incorporate spatial socioeconomic data.

Background: Progression of human immunodeficiency virus type 1 (HIV-1) infection to the acquired immunodeficiency syndrome (AIDS) is associated with elevated total IgE; however, previous cross-sectional studies have differed in their assessment of concurrent changes in allergic disease prevalence., Objective: Assessment of changes in aeroallergen-specific IgE during progression from early to late HIV disease., Methods: Total IgE, aeroallergen-specific IgE (rye grass, ragweed, Alternaria, dust mite, and cat), IFN-gamma, IL-4, and soluble CD23 (sCD23) were measured in a longitudinal study of 20 subject who had progressed from early-HIV infection (mean CD4 lymphocyte count of 650/mm3) to AIDS (mean CD4 lymphocyte count of 40/mm3) over an average of 4 years., Results: Prevalence of positive aeroallergen specific-IgE assays in early HIV disease (T1 subjects with 13 positives) decreased with progression to late disease (five subjects with nine positive, P = .057), while total IgE increased from a median of 69 to 116 IU/mL. IFN-gamma and IL-4 were unchanged, while sCD23 decreased from a median of 72 to 9 U/mL (P = .0005) with disease progression in the full cohort. In contrast to other subjects, the subgroup of individuals with total IgE > 150 IU/mL in both early and late HIV disease demonstrated an increased frequency of aeroallergen-specific IgE., Conclusions: The elevation of total IgE associated with rapid HIV-1 disease progression was unexplained by concurrent changes in aeroallergen-specific IgE, IL-4, IFN-gamma, or sCD23. Overall, aeroallergen-specific IgE expression was less prevalent with HIV-1 progression, except in those individuals with elevated total IgE both before and after progression to AIDS.

The purpose of this in vitro study was to compare the effects of a 1-min immersion and of 4-min immersions in an acidulated phosphate fluoride (1.23% APF) foam, a 1.23% APF gel, a 2.0% sodium fluoride (NaF) gel, and water on surface topography and on weight of a composite resin (APH). Forty composite resin specimens were placed into eight groups (N = 5 each). For each treatment, a group of specimens was immersed for either 1 or 4 min (four 1-min immersions). Specimens were weighed before and after each immersion. The surface topography of two scanning electron micrographs of each specimen was scored visually by two investigators. Inter-rater reliability was r = 0.75 (intraclass correlation coefficient). There were no significant differences in the mean visual scores or weight among the 1-min immersion groups. Significantly greater surface changes and weight loss of this composite resin occurred following 4-min immersions in either 1.23% APF foam or gel as compared with those immersed in either 2.0% NaF gel or water (P 0.0001; one-way ANOVA, Tukey's Studentized Range Test).

This investigation compared pulpal response to threaded pin techniques with response to retentive slot techniques. The teeth were restored with composite resin. Twenty-four teeth were assigned to three treatment groups in one Macaca mulatta monkey. Ten teeth (group 1) received 32 TMS 0.021-inch self-threading pins. Ten teeth (group II) received circumferential slot retention 1 mm deep, 0.5 mm inside the dentinoenamel junction. Four teeth (group III) served as controls. Groups I and II were restored with composite resin. Fourteen days later, the teeth were removed, demineralized, serially sectioned, and stained with hematoxylin and eosin. Chi-square analysis indicated more pulp inflammation when self-threading pins were used (p less than 0.5). Pins placed within 0.5 mm of the pulp elicited severe inflammatory responses, and those placed further than 1 mm had minimal effect. Little correlation existed between remaining dentin thickness and adverse pulp response when slot retention was used.

The use of threaded endodontic dowels is a controversial issue. The purpose of this study was to compare the potential for root fracture resulting from the cementation of nine threaded and three nonthreaded endodontic dowel systems. The clinical crowns of 140 extracted premolars were removed at the cementoenamel junction. The teeth were randomly assigned to the following treatment groups of 10 teeth each: Group 1, endodontically instrumented but not obturated; group 2, instrumented and obturated; group 3, instrumented, obturated, and restored with custom-cast gold dowel and cores; groups 4 and 5, instrumented, obturated, and restored with prefabricated, nonthreaded dowels; and groups 6 through 14, instrumented, obturated, and restored with one of nine prefabricated, threaded dowels. All dowels were inserted according to manufacturer's directions, removed, and cemented with vinyl polysiloxane impression material. Each specimen was demineralized and cleared. Photographs at 1:1 magnification were taken to assess dowel fractures. Fisher's test and chi square analysis were performed to evaluate the differences between post types, and between posted and nonposted controls (p less than 0.05). The results indicate no statistically significant differences between dowel types when compared with each other, regardless of dowel shape, taper, or presence or absence of threads, or when compared to instrumented, nonobturated controls. The amount of remaining dentin and existing root morphology may be a determining factor for endodontically treated teeth to resist fracture during dowel placement.

A model for observing the three-dimensional pattern of cracking associated with placement of self-threading retentive pins was developed. Four sizes of self-threading pins were placed in extracted posterior tooth samples. The pins were subsequently removed and the samples coated with butyl acetate lacquer except for the pin channel orifice. Samples were immersed in dye solution followed by a demineralization and dehydration process. Samples were placed in methyl salicylate until cleared. Cleared samples were examined for dye penetration into the pin channel and communication with the pulp chamber. Comparisons were made of the patterns created by the four sizes of retentive pins. Results showed that more extensive cracks occurred with the larger size pins and that crack communication with the pulp chamber occurred more frequently with the larger pins.

The efficacy of a once-daily combination of chlorthalidone 50 mg plus triamterene 50 mg or chlorthalidone 100 mg plus triamterene 100 mg was compared to that of chlorthalidone 50 mg or 100 mg. This double-blind study was carried out in eighty-eight patients over a treatment period of 12 weeks. All patients entered the active medication period of 12 weeks after a placebo run-in period of 3 to 7 days, during which pretibial or malleolar pitting oedema averaging 2 to 4 mm developed. All patients started at the lower doses, i.e. forty-one started on chlorthalidone 50 mg plus triamterene 50 mg and forty-seven started on chlorthalidone 50 mg. The protocol provided for doubling the dose (but not for reducing it thereafter) at any time during the 12-week period when control of oedema was deemed inadequate. Eight of the combination therapy patients and sixteen of those on chlorthalidone required the higher doses. By Week 12, 96% of the chlorthalidone plus triamterene patients and 100% of the chlorthalidone patients had shown a reduction of at least 2 mm in depth of pits, and 92% and 72%, respectively, had complete disappearance of oedema. The decreases in pitting oedema were paralleled by mean weight losses of 2.4 kg and 3.1 kg, respectively, for the combination treatment group and the chlorthalidone group. Average serum potassium levels throughout the 12-week treatment period were 3.70 mEq/L for the patients taking the combination compared to 3.41 mEq/L of those taking chlorthalidone.(ABSTRACT TRUNCATED AT 250 WORDS)

A double-blind study was carried out in obese patients with moderately severe hypertension to assess the efficacy and tolerability of 2.5 mg indapamide as a once-a-day Step 1 drug compared to 50 mg hydrochlorothiazide also as a once-a-day Step 1 drug; to assess the efficacy and tolerability of a fixed daily dose of 2.5 mg indapamide administered concomitantly with methyldopa starting at 500 mg daily; and to compare the findings of efficacy and tolerability of 2.5 mg indapamide daily with those of 50 mg hydrochlorothiazide daily as Step 1 agents when methyldopa is the Step 2 drug. Twenty-nine patients completed the study and were evaluated. Nine patients achieved the study criterion of reduction of average standing diastolic pressure to 90 mmHg or less when treated with Step 1 medication only. Twenty patients required the addition of methyldopa to their Step 1 medication: 10 patients took 2.5 mg indapamide with an average constant daily dose of 1100 mg methyldopa and 10 patients took 50 mg hydrochlorothiazide with an average constant daily dose of 1575 mg methyldopa to achieve blood pressure control. All groups had mean diastolic pressure controlled at or below the 90 mmHg criterion during the period of constant methyldopa dosage for those patients who required Step 2 therapy. There were no significant differences between groups with respect to diastolic pressure during the constant dosage period. The indapamide patients required significantly (p less than 0.05) less methyldopa than did the hydrochlorothiazide patients in order to maintain satisfactory control of diastolic blood pressure. The number of responders was greater in the 2.5 mg indapamide + methyldopa group than it was in the 50 mg hydrochlorothiazide + methyldopa group, and responses were achieved more rapidly in the former group than in the latter. Indapamide (2.5 mg per day) was effective and well tolerated when used alone or as Step 1 medication in combination with methyldopa as Step 2 medication, and it compared favourably in this regard with hydrochlorothiazide.

The technique described offers the patient an esthetic temporary crown for a horizontally fractured vital anterior tooth without resorting to emergency root canal therapy or pins.

Chlorthalidone 50 mg/triamterene 50 mg in once-daily oral doses was as effective in reducing blood pressure as chlorthalidone 50 mg alone. The decrease in serum potassium was statistically significantly less with the combination than for chlorthalidone. There were no notable differences between the treatments in any other measure of laboratory safety or adverse reaction.

The use of a multisectional stone mold is advocated for the fabrication of prosthetic ears. Less force is required in the deflasking procedure with this technique, reducing the risk of fracturing the mold or tearing the prosthesis. This technique requires more time and care in the flasking procedure. Convergence of the sections is of particular importance. The potential for multiple section lines may result in a need for more surface finishing of the prosthesis.

We studied the adsorption, morphological, and serological characteristics of selected Actinomyces and related species. Evaluation of uranyl acetate-stained cells by electron microscopy revealed wide variations among strains in the frequency of surface fimbriae. These variations did not always correlate with the percent adsorption to saliva-treated hydroxyapatite of the various Actinomyces strains. However, two strains of Rothia dentocariosa possessing no surface fimbriae and five strains of A. israelii possessing very few surface fimbriae exhibited feeble adsorption to saliva-treated hydroxyapatite. Although the calculated number of adsorption sites on saliva-treated hydroxypatite did not vary widely among the strains tested, significant differences were observed in the affinities calculated for some species or serotypes. The mean affinities for strains of A. viscosus serotype 2 and A. naeslundii serotype 3 were similar, and these strains adsorbed well to saliva-treated hydroxyapatite. The mean adsorption and affinity for the A. naeslundii strain serotype 1 and all strains of A. israelii tested were significantly less than those determined for the A. viscosus serotype 2 or A. naeslundii serotype 3 strains. Adsorption inhibition activity of antiserum to strain T14V, previously shown to be solely related to antibodies in immune serum directed against the VA1 fimbria (fibril) antigen, was removed by preadsorption of the antiserum with most A. viscosus and A. naelundii strains, but not with A. israelii strains. This suggests some cross-reactivity among strains of A. viscosus and A. naeslundii but not A. israelii. Adsorption to saliva-treated hydroxyapatite of all A. viscosus and A. naeslundii strains tested was strongly inhibited by fimbriae isolated from A. viscosus strain T14V. Collectively, these data suggest that the adsorption of certain A. viscosus and A. naeslundii strains is mediated by surface fimbriae, many of which appear serologically cross-reactive with strain T14V fimbriae.