Assessing the environmental performance of urban wastewater systems using the INSA model: application to the Algés-Alcântara wastewater system, in Portugal

Although the application of complex integrated models to wastewater systems is useful, it is often difficult to implement and not always suitable for the design of new systems or for their rehabilitation. Integrated simple approaches that allow assessing the environmental performance of urban wastewater systems may be advantageous, especially during the initial phases of the system planning process. This paper presents an original, straightforward approach that can be used for planning, design and operation of urban wastewater systems. The INtegrated Simplified Approach (INSA) combines the concepts of performance indicators with mass balances and can be applied to wastewater systems as a management support tool, particularly in situations where there is lack of data, economic limitations or time constraints. The INSA was applied to the Algés-Alcântara wastewater system to evaluate its environmental performance and to simulate the individual or combined impact of the rehabilitation measures proposed, thus defining their priority. The results clearly indicate that, despite the investment already made upgrading the wastewater treatment plant (WWTP), the proposed interventions must be implemented to ensure an acceptable environmental performance of the system. In addition, the results demonstrate the significant pollution loads present in stormwater, frequently higher than the pollution loads discharged into receiving waters during dry weather.

Risk estimates for persistent high-risk human papillomavirus infections as surrogate endpoints of progressive cervical disease critically depend on reference category: analysis of the combined prospective cohort of the New Independent States of the Former Soviet Union and Latin American Screening Studies

Summary

To make feasible future clinical trials with new-generation human papillomavirus (HPV) vaccines, novel virological surrogate endpoints of progressive disease have been proposed, including high-risk HPV (HR-HPV) persistence for six months (6M+) or 12 months (12M+). The risk estimates (relative risks [RRs]) of these ‘virological endpoints’ are influenced by several variables, not yet validated adequately. We compared the impact of three referent groups: (i) HPV-negative, (ii) HPV-transient, (iii) HPV-mixed outcome on the risk estimates for 6M+ or 12M+ HR-HPV persistence as predictors of progressive disease. Generalized estimating equation models were used to estimate the strength of 6M+ and 12M+ HR-HPV persistence with disease progression to squamous intraepithelial lesions (SILs), cervical intraepithelial neoplasia (CIN) grade 1 +, CIN2+, CIN/SIL endpoints, comparing three optional reference categories (i)-(iii) in a prospective sub-cohort of 1865 women from the combined New Independent States of the Former Soviet Union (NIS) and Latin American Screening (LAMS) studies cohort ( n = 15,301). The RRs of these viral endpoints as predictors of progressive disease are affected by the length of viral persistence (6M+ or 12M+) and the surrogate endpoint (SIL, CIN1, CIN2, CIN/SIL). Most dramatic is the effect of the referent group used in risk estimates, with the HPV-negative referent group giving the highest and most consistent RRs for both 6M+ and 12M+ viral persistence, irrespective of which surrogate is used. In addition to deciding on whether to use 6M+ or 12M+ persistence criteria, and cytological, histological or combined surrogate endpoints, one should adopt the HPV-negative referent group as the gold standard in all future studies using viral persistence as the surrogate endpoint of progressive disease.

Safety of screening with Human papillomavirus testing for cervical cancer at three-year intervals in a high-risk population: experience from the LAMS study

OBJECTIVES

To assess whether human papillomavirus (HPV) testing is a safe enough approach to warrant extension of the screening intervals of baseline Papanicolaou (Pap)-/HPV- women in low-income settings.

METHODS

Of the >1000 women prospectively followed up as part of the Latin American Screening (LAMS) Study in São Paulo, Campinas, Porto Alegre) and Buenos Aires, 470 women with both baseline cytology and Hybrid Capture 2 (HC2) results available were included in this analysis. These baseline Pap-negative and HC2- or HC2+ women were controlled at six-month intervals with colposcopy, HC2 and Pap to assess the cumulative risk of incident Pap smear abnormalities and their predictive factors.

RESULTS

Of the 470 women, 324 (68.9%) were high-risk HPV (hrHPV) positive and 146 (31.1%) were negative. Having two or more lifetime sex partners (odds ratio [OR] = 2.63; 95% CI 1.70-3.51) and women using hormonal contraception (OR = 2.21; 95% CI 1.40-3.51) were at increased risk for baseline hrHPV infection. Baseline hrHPV+ women had a significantly increased risk of incident abnormal Pap smears during the follow-up. Survival curves deviate from each other starting at month 24 onwards, when hrHPV+ women start rapidly accumulating incident Pap smear abnormalities, including atypical squamous cells (ASC) or worse (log-rank; P < 0.001), low-grade squamous intraepithelial lesions (LSIL) or worse (P < 0.001) and high-grade squamous intraepithelial lesions (HSIL) (P = 0.03). Among the baseline hrHPV- women, the acquisition of incident hrHPV during the follow-up period significantly increased the risk of incident cytological abnormalities (hazard ratio = 3.5; 95% CI 1.1-11.7).

CONCLUSION

These data implicate that HPV testing for hrHPV types might be a safe enough approach to warrant extension of the screening interval of hrHPV-/Pap-women even in low-resource settings. Although some women will inevitably contract hrHPV, the process to develop HSIL will be long enough to enable their detection at the next screening round (e.g. after three years).

Drug addiction is not an independent risk factor for oncogenic human papillomavirus infections or high-grade cervical intraepithelial neoplasia: case-control study nested within the Latin American Screening study cohort

Drug abuse (addiction) has been listed among the risk factors for human papillomavirus (HPV) infections, but no case-control studies exist to rule out sexual behaviour and other potential confounders. The aim of this study is to evaluate the role of drug addiction as an independent predictor of HR-HPV infections and (cervical intraepithelial neoplasia) CIN2+ in an age-matched case-control (1:4) study nested within the prospective Latin American Screening (LAMS) study cohort. All 109 women in the LAMS cohort (n = 12,114) reporting drug abuse/addiction were matched with four controls (n = 436) of non-abusers strictly by age. Conditional logistic regression analysis was used to estimate the co-variates of drug abuse, and the whole series (n = 545) was analysed for predictors of HR-HPV and CIN2+ using univariate and multivariate regression models. Oncogenic HPV infections were significantly (P = 0.019) more prevalent among abusers (37.7%) than in controls (21.9%), but there was no difference in high-grade squamous intraepithelial lesions (P = 0.180) or CIN2+ lesions (P = 0.201). In multivariate conditional logistic regression, number of lifetime sexual partners (P = 0.0001), ever smokers (P = 0.0001), non-use of OCs (P = 0.013), ever having sexually transmitted diseases (STD) (P = 0.041) and no previous Pap smear (P = 0.027) were independent co-variates of drug addiction. Drug abuse was not an independent risk factor of high-risk (HR)-HPV infection, which was significantly predicted by (1) age below 30 years (P = 0.045), (2) more than five lifetime sexual partners (P = 0.046) and (3) being current smoker (P = 0.0001). In multivariate model, only HR-HPV infection was an independent risk factor of CIN2+ (P = 0.031), with adjusted OR = 11.33 (95% CI 1.25–102.50). These data indicate that drug addiction is not an independent risk factor of either HR-HPV infections or CIN2+, but the increased prevalence of HR-HPV infections is explained by the high-risk sexual behaviour and smoking habits of these women.

Self-sampling for human papillomavirus (HPV) testing as cervical cancer screening option. Experience from the LAMS study

PURPOSE

To compare Hybrid Capture II (HC2) in detecting high-risk (HR) HPV in patient-collected vaginal samples with those obtained using gynaecologist collected samples.

METHODS

Patients were submitted to Pap smears, visual inspection with acetic acid (VIA) and HC2 for hr-HPV.

RESULTS

A total of 1,081 HC2 tests for HR-HPV were performed: 770 (71.2%) samples were collected by a physician and 311 (28.8%) were self-collected by the patients. In detecting any cervical lesion, the sensitivity of HC2 collected by a physician was higher (92.86%) than that (37.5%) in the self-sampling group. Negative predictive value (NPV) was high for both, 99.69% and 93.75%, respectively. Using the CIN2 cutoff, performance of HC2 was significantly improved: 92.9% and 62.5%, respectively. HC2 specificity for any cervical lesion and for CIN2 or higher were close to 90% in both groups.

CONCLUSIONS

Self-sampled HPV testing is a powerful option to increase the detection of cervical lesions in women segregated from prevention programs.

Human papillomavirus testing as an optional screening tool in low-resource settings of Latin America: experience from the Latin American Screening study

Hybrid capture II (HC II) test for oncogenic human papillomaviruses (HPV) was carried out in a cohort of 4284 women at their first clinical visit. Overall prevalence of HPV was 17.1%, decreasing with age from 33.9% among women below 20 years to only 11.0% among those older than 41 years. HPV prevalence was significantly higher among current smokers (odds ratio [OR] = 1.31; 95% CI 1.1-1.6), in women with two or more lifetime sexual partners (OR = 1.9; 95% CI 1.6-2.4), and those women with two or more sexual partners during the past 12 months prior to examination (OR = 1.6; 95% CI 1.2-2.2). HPV detection increased in parallel with increasing cytologic abnormality, being highest in women with high-grade squamous intraepithelial lesion (P= 0.001). Specificity of the HPV test in detecting histologically confirmed cervical disease was 85% (95% CI 83.9-86.1). Sensitivity of the HPV test in detecting histologic abnormalities increased in parallel with disease severity, ranging from 51.5% for cervical intraepithelial neoplasia (CIN) 1 to 96.5% for CIN 3 and 100.0% for cancer, with respective decline of positive predictive value. These data suggest that HPV testing with HC II assay might be a viable screening tool among this population with relatively high prevalence of cervical disease.

Human papillomavirus testing as an optional screening tool in low-resource settings of Latin America: experience from the Latin American Screening study

Hybrid capture II (HC II) test for oncogenic human papillomaviruses (HPV) was carried out in a cohort of 4284 women at their first clinical visit. Overall prevalence of HPV was 17.1%, decreasing with age from 33.9% among women below 20 years to only 11.0% among those older than 41 years. HPV prevalence was significantly higher among current smokers (odds ratio [OR] = 1.31; 95% CI 1.1–1.6), in women with two or more lifetime sexual partners (OR = 1.9; 95% CI 1.6–2.4), and those women with two or more sexual partners during the past 12 months prior to examination (OR = 1.6; 95% CI 1.2–2.2). HPV detection increased in parallel with increasing cytologic abnormality, being highest in women with high-grade squamous intraepithelial lesion (P = 0.001). Specificity of the HPV test in detecting histologically confirmed cervical disease was 85% (95% CI 83.9–86.1). Sensitivity of the HPV test in detecting histologic abnormalities increased in parallel with disease severity, ranging from 51.5% for cervical intraepithelial neoplasia (CIN) 1 to 96.5% for CIN 3 and 100.0% for cancer, with respective decline of positive predictive value. These data suggest that HPV testing with HC II assay might be a viable screening tool among this population with relatively high prevalence of cervical disease.

Factors predicting intermediate endpoints of cervical cancer and exposure to human papillomavirus (HPV) infections in young women screened as potential targets for prophylactic HPV vaccination in south of Brazil

OBJECTIVE

To explore the predictors of intermediate endpoints of cervical cancer in 500 women living in Porto Alegre.

STUDY DESIGN

Five hundred randomly selected women (mean age 20.3 years, range 15-25) were screened using PCR detecting 25 HPV types (HPV6, 11, 16, 18, 31, 33, 34, 35, 39, 40, 42, 43, 44, 45, 51, 52, 53, 54, 56, 58, 59, 66, 68, 70, and 74). Women were interviewed and serum samples were analysed for antibodies to HPV16 and HPV18 VLPs. Regression models were constructed to analyse predictive factors for (a) HPV PCR status, (b) HPV16-seropositivity, (c) HPV18-seropositivity, and (d) SIL in the PAP smear, used as intermediate endpoints of cervical cancer.

RESULTS

Specific HPV types were identified in 137 (27.4%) of the 157 (31.4%) PCR-positive women. PAP test result was the most powerful independent predictor of HPV status in PCR (p = 0.0001), followed by the sexual activity started (p = 0.001) (adjusted OR 34.075, 95% CI: 4.650-249.715). PAP test SIL was independently predicted only by the HPV PCR status (p = 0.0001) (OR 7.561, 95% CI: 2.787-20.514). HPV16 and HPV18 serostatus were the most significant predictors of each other (p=0.0001), and the life-time number of sexual partners was more significant (p=0.001) predictor of HPV16 than HPV18 serostatus (p = 0.049).

CONCLUSION

These data are useful in evaluating the exposure status of the women to the risk factors of cervical cancer in south of Brazil.

Evaluation of visual inspection with acetic acid (VIA), Lugol's iodine (VILI), cervical cytology and HPV testing as cervical screening tools in Latin America. This report refers to partial results from the LAMS (Latin AMerican Screening) study

OBJECTIVES

To assess the performance indicators of visual inspection with acetic acid (VIA) and visual inspection with Lugol's iodine (VILI) in four Latin American centres participating in the ongoing Latin AMerican Screening (LAMS) study, in settings with moderate incidence of cervical disease and with poorly to moderately well-organized cervical cancer screening.

SETTING

Three Brazilian centres (São Paulo, Campinas and Porto Alegre) and one Argentine centre (Buenos Aires) recruited a total of 11,834 healthy women to undergo VIA, VILI, conventional Pap smear and Hybrid Capture II (HCII).

METHODS

Women who had a positive result from any of these tests were subjected to colposcopy and biopsies (if necessary), and women with high-grade cervical intraepithelial neoplasia (CIN) were properly treated. To control for verification bias, 5% of women with normal tests were referred for colposcopy, as were 20% of HCII-negative women.

RESULTS

Data on VIA (n=11,834), VILI (n=2994), conventional Pap smear (n=10,138) and HCII (n=4195) were available for test comparisons, calculating sensitivity, specificity, and positive and negative predictive values. Overall test positivity was 11.6% for VIA, 23.0% for VILI, 2.2% for Pap smear (LSIL threshold), 1.1% for Pap smear (HSIL threshold) and 17.1% for HCII. VIA was positive in 61.8% of the women with CIN 1, 57.0% of those with CIN 2, 35.0% of women with CIN 3 and in 21 of 28 (75%) of women with cancer. Approximately 10% of women with no detectable disease had an abnormal VIA. Regarding VILI, 83.3% of women diagnosed with CIN 1 and 62.5% of those with CIN 3 had an abnormal test. VILI failed to detect one of three cases of cancer. Both the sensitivity, specificity and positive predictive value of VIA and VILI in detecting CIN 2 or CIN 3 could be significantly improved depending on the combination with Pap smear or HCII (sensitivity up to 100.0% and specificity up to 99.8%).

CONCLUSIONS

The LAMS study failed to reproduce the performance figures obtained with VIA and VILI (as stand-alone tests) in some other settings, where the prevalence of cervical disease was higher. However, a combined use of VIA or VILI with the Pap test or HCII allowed specific detection of cervical abnormalities.

Comparing PAP smear cytology, aided visual inspection, screening colposcopy, cervicography and HPV testing as optional screening tools in Latin America. Study design and baseline data of the LAMS study

OBJECTIVES

This is a European Commission (EC)-funded ongoing study known as the LAMS (Latin American Screening) study, where PAP smear/liquid-based cytology and screening colposcopy were compared with i) three optional screening tools [visual inspection with acetic acid (VIA), or Lugol's iodine (VILI), cervicography] and with ii) Hybrid Capture II from a) conventional samples and from b) self-samples, in women at different risk for cervical cancer in Brazil and Argentina.

STUDY DESIGN

During 2002-2003, a cohort of 12,107 women attending four clinics: Campinas (CA), Sao Paulo (SP), Porto Alegre (PA) and Buenos Aires (BA), were interviewed for risk factors, and examined using the 8 diagnostic arms. Colposcopy was performed for women positive in any test and for 5% of women with baseline PAP-negative and 20% of HCII-negatives. All high-grade lesions (CIN2/3) were treated, and low-grade CIN are prospectively followed-up.

RESULTS

Of the 12,107 women, the following baseline data are available: epidemiological data (n=11,996), conventional PAP smears (n=10,363), LBC, SurePATH (n=320), LBC, DNA-Citoliq (n=1,346), VIA (n=12.067), VILI (n=3,061), cervicography (n=279), screening colposcopy (n=3,437), HCII conventional (n=4,710), HCII self-sampling (n=246) and cervical biopsies (n=1,524). The four sub-cohorts differ significantly in all their baseline data on the implicated risk factors of cervical cancer, consonant with their origin from regions with different cancer incidence. Around 95% of all PAP smears were negative, with slight variations in the prevalence of LSIL and HSIL between the four centers. Significant differences were found in the detection rates of abnormal findings in VIA, VILI and colposcopy between the four centers (p=0.0001). The prevalence of HPV was practically identical (16.5-18.8%) in all four cohorts (p=0.486), with no differences in the relative viral loads. Biopsy results were different depending on whether the women underwent screening colposcopy (BA) or elective colposcopy (others).

CONCLUSION

Four cohorts with significantly different baseline data are available, and prospective follow-up of these women permits analysis of whether variations in cervical cancer incidence in these regions is due to i) different natural history of the precursor lesions, or ii) due to different levels of exposure to the known risk factors.

Sustainable sewage solutions for small agglomerations

In a significant number of European countries, the need for providing appropriate treatment for the effluents of small rural communities is still especially relevant. In fact, in countries like Portugal, Spain, and many others, significant amounts of investment will be addressed in the next few years to the construction of small Wastewater Treatment Plants (WWTP). The problems faced when constructing and operating WWTP serving small communities may be relevant when energy and labour costs are relatively high, or when the visual impact on the surrounding areas is especially negative. Sustainable treatment solutions require the selection of appropriate technologies using fewer resources. In this paper, information is presented about sustainability indicators of twenty-one small secondary wastewater treatment plants, including conventional (trickling filters and extended aeration plants) and non-conventional treatment systems (constructed wetlands). The data refer to allocated areas per inhabitant, amounts of concrete per inhabitant, power per inhabitant, and construction and installation costs per inhabitant. The data seem to show that for different reasons, constructed wetlands are promising treatment solutions for application to rural areas in particular because of the relatively low power requirements and relatively low construction costs for served populations below 500 inhabitants.

Modelling in-sewer pollutant degradation processes in the Costa do Estoril sewer system

Characteristics of wastewater vary during transportation through sewer systems as a result of a number of processes. Under aerobic conditions, in long sewer systems, the reduction of the BOD or COD may be similar to the reduction obtained in conventional primary settling tanks. The mathematical model that was developed is based on a number of different existing models: the ASM n. 1 and ASM n. 2 models, the AEROSEPT model and the WATS model. The model also includes a prediction of reaeration at falls. The module of the anoxic conditions was adapted from the ASM n. 2 model. This module is a first attempt to model the degradation of organic matter in sewer systems under anoxic conditions. The mathematical model was applied to the Costa do Estoril intercepting sewer, and the obtained results are discussed taken into account the experimental data that was collected during a three-month period. Average removals of dissolved COD over 20% have been obtained. In the paper special emphasis is given to the importance of the performance of the Costa do Estoril sewer system as a biological reactor.

Primary structure deduction and molecular modelling from a cDNA of a cellobiohydrolase-like protein from the white-rot fungus Coriolus versicolor

Molecular cloning and cDNA sequencing analysis were used to elucidate the primary structure of a cellulase-like structure from the white-rot fungus Coriolus versicolor. The cDNA of interest was isolated from a cDNA library obtained from C. versicolor mycelia grown on cellulase inducer medium. A pattern search showed that this cellulase belongs to the glycosyl hydrolases family 6. From the deduced amino acid sequence, models of the binding and catalytic domains were built by homology modelling. The constructed models present a typical cellulose-binding domain at the N-terminal region, a rich Pro, Ser, Thr linker peptide, and a catalytic domain at the C-terminus region.

Cervical Cancer Screening in Porto Alegre, Brazil: Alternative Methods for Detecting Cancer Precursors in a Developing Country

OBJECTIVE

This study was conducted to test the performance characteristics of cervical cancer screening by visual inspection of the cervix with acetic acid and iodine solution.

METHODS

A total of 100 women were screened for cervical cancer by Pap smear and naked eye inspection of the cervix after application of acetic acid and iodine solution.

RESULTS

Comparing visual inspection to the Pap test, a sensitivity of 85.7%, specificity of 78.5%, and concordance of 79% (p < .0011) was established. Comparing the Pap test with colposcopy, the corresponding figures were 42.9%, 92.3%, and 66.6% (p < .077), respectively. Visual inspection compared to colposcopy showed corresponding figures of 100%, 7.7%, and 55.5% (p = .48), respectively. Colposcopy and biopsy had an agreement of 100%.

CONCLUSIONS

Visual inspection with acetic acid and iodine solution proved to be a reasonable method of screening for cervical cancer precursors.

A randomized, placebo-controlled trial of granulocyte-macrophage colony-stimulating factor and nucleoside analogue therapy in AIDS

Preliminary preclinical and clinical data suggest that granulocyte-macrophage colony-stimulating factor (GM-CSF) may decrease viral replication. Therefore, 105 individuals with AIDS who were receiving nucleoside analogue therapy were enrolled in a placebo-controlled, double-blind study and were randomized to receive either 125 microgram/m(2) of yeast-derived, GM-CSF (sargramostim) or placebo subcutaneously twice weekly for 6 months. Subjects were evaluated for toxicity and disease progression. A significant decrease in mean virus load (VL) was observed for the GM-CSF treatment group at 6 months (-0.07 log(10) vs. -0.60 log(10); P=.02). More subjects achieved human immunodeficiency virus (HIV)-RNA levels <500 copies/mL at >/=2 evaluations (2% on placebo vs. 11% on GM-CSF; P=.04). Genotypic analysis of 46 subjects demonstrated a lower frequency of zidovudine-resistant mutations among those receiving GM-CSF (80% vs. 50%; P=.04). No difference was observed in the incidence of opportunistic infections (OIs) through 6 months or survival, despite a higher risk for OI among GM-CSF recipients. GM-CSF reduced VL and limited the evolution of zidovudine-resistant genotypes, potentially providing adjunctive therapy in HIV disease.