Recent trends in maternal and child health inequalities in Latin America and the Caribbean: analysis of repeated national surveys

BACKGROUND

Although most Latin American and the Caribbean (LAC) countries made important progress in maternal and child health indicators from the 1990s up to 2010, little is known about such progress in the last decade. This study aims at documenting progress for each country as a whole, and to assess how within-country socioeconomic inequalities are evolving over time.

METHODS

We identified LAC countries for which a national survey was available between 2011-2015 and a second comparable survey in 2018-2020. These included Argentina, Costa Rica, Cuba, the Dominican Republic, Guyana, Honduras, Peru, and Suriname. The 16 surveys included in the analysis collected nationally representative data on 221,989 women and 152,983 children using multistage sampling. Twelve health-related outcomes were studied, seven of which related to intervention coverage: the composite coverage index, demand for family planning satisfied with modern methods, antenatal care (four or more visits and eight or more visits), skilled attendant at birth, postnatal care for the mother and full immunization coverage. Five additional impact indicators were also investigated: stunting prevalence among under-five children, tobacco use by women, adolescent fertility rate, and under-five and neonatal mortality rates. For each of these indicators, average annual relative change rates were calculated between the baseline and endline national level estimates, and changes in socioeconomic inequalities over time were assessed using the slope index of inequality.

RESULTS

Progress over time and the magnitude of inequalities varied according to country and indicator. For countries and indicators where baseline levels were high, as Argentina, Costa Rica and Cuba, progress was slow and inequalities small for most indicators. Countries that still have room for improvements, such as Guyana, Honduras, Peru and Suriname, showed faster progress for some but not all indicators, although also had wider inequalities. Among the countries studied, Peru was the top performer in terms of increasing coverage and reducing inequalities over time, followed by Honduras. Declines in family planning and immunization coverage were observed in some countries, and the widest inequalities were present for adolescent fertility and antenatal care coverage with eight or more visits.

CONCLUSIONS

Although LAC countries are well placed in terms of current levels of health indicators compared to most low- and middle-income countries, important inequalities remain, and reversals are being observed in some areas. More targeted efforts and actions are needed in order to leave no one behind. Monitoring progress with an equity lens is essential, but this will require further investment in conducting surveys routinely.

Children of more empowered women are less likely to be left without vaccination in low- and middle-income countries: A global analysis of 50 DHS surveys

Background

To help provide a global understanding of the role of gender-related barriers to vaccination, we have used a broad measure of women’s empowerment and explored its association with the prevalence of zero-dose children aged 12-23 months across many low- and middle-income countries, using data from standardized national household surveys.

Methods

We used data from Demographic and Health Surveys (DHS) of 50 countries with information on both women’s empowerment and child immunisation. Zero-dose was operationally defined as the proportion of children who failed to receive any doses of the diphtheria, pertussis, and tetanus containing vaccines (DPT). We measured women’s empowerment using the SWPER Global, an individual-level indicator estimated for women aged 15-49 years who are married or in union and with three domains: social independence, decision-making and attitude towards violence. We estimated two summary measures of inequality, the slope index of inequality (SII) and the concentration index (CIX). Results were presented for individual and pooled countries.

Results

In the country-level (ecological) analyses we found that the higher the proportion of women with high empowerment, the lower the zero-dose prevalence. In the individual level analyses, overall, children with highly-empowered mothers presented lower prevalence of zero-dose than those with less-empowered mothers. The social independence domain presented more consistent associations with zero-dose. In 42 countries, the lowest zero-dose prevalence was found in the high empowerment groups, with the slope index of inequality showing significant results in 28 countries. When we pooled all countries using a multilevel Poisson model, children from mothers in the low and medium levels of the social independence domain had respectively 3.3 (95% confidence interval (CI) = 2.3, 4.7) and 1.8 (95% CI = 1.5, 2.1) times higher prevalence of zero-dose compared to those in the high level.

Conclusions

Our country-level and individual-level analyses support the importance of women’s empowerment for child vaccination, especially in countries with weaker routine immunisation programs.

Cardiac rehabilitation in COVID-19 pandemic period

Background

The current COVID-19 pandemic constitutes a challenge in cardiovascular disease (CVD) management. Little is known on how the virus impacts cardiac rehabilitation (CR) programs (CRP) safety and efficacy.

Aim

To evaluate the efficacy of basic sanitary procedures to limit the risk of virus spreading in patients undergoing cardiac rehabilitation in ambulatory setting.

Methods

From august to October 2020, all patients admitted in a single ambulatory CR program were screened for COVID-19 infection before and after CR. Negative naso-pharyngeal swab through RT-PCR was mandatory within seven days before starting the program, and advised after leaving the program. Serologic tests were also advised before and after the CRP. Number of patients were reduced from 9 to 4 in each group, 2 meters distancing respected, and all patients and staff had to wear surgical mask during sessions. Regular hand washing and hydro-alcoholic solutions use were mandatory for both patients and health professionnals. Material disinfection was systematic before and after each session.

Results

Among the 81 patients included, 63 (76%) were male, mean age was 57±11 years (see table). Sanitary protection measures were well applied and tolerated, especially use of surgical mask during exercice sessions. After RT-PCR on nasal swab, none (0%) were positive before entering CR and only 2 (2.7%) were tested positive after CR. These two patients were asymptomatic. The other patients in the same group as those having positive nasal test after CR were tested negative and were asymptomatic. According to serological analysis, the same 3 patients (3.8%) had anti-bodies against SARS-COV-2 before and after participating CR (see graph). These 3 patients were negative on nasal swab before and after CR. No seroconversion was observed. Mean delay between first and second RT-PCR on nasal swab and serological analysis were 30±15 and 32±15 days, respectively. In total (before and after CR), 5 patients (6.0%) were tested positive with SARS-COV-2. Those 5 patients were younger (mean age 51 years old versus 58, p=0.2), with better functional capacity before and after CR: respectively 7.1 METs (versus 5.2 METs, p=0.014) and 8.3 METs (versus 6.3 METs, p=0.03). In COVID+ patients, improvement of functional capacity was similar to COVID− patients: respectively 0.8 METs (p=0.9) and 15 Watts (p=0.9).

Conclusion

During COVID-19 pandemic, cardiac rehabilitation is not associated with risk of infection with SARS-CoV-2, provided that basic sanitary measures are stricly applied. It is also associated with functionnal capacity improvement, especially in patients who previously had COVID-19.

Funding Acknowledgement

Type of funding sources: None. Patients baseline characteristics in CRPatients COVID-19 status in CR

The Bronchiectasis Severity Index and FACED score for assessment of the severity of bronchiectasis

INTRODUCTION

Bronchiectasis (BC) is a multidimensional and etiologically diverse disease and, therefore, no single parameter can be used to determine its overall severity and prognosis. In this regard, two different validated scores are currently used to assess the severity of non-cystic fibrosis bronchiectasis (NCFB): the FACED score and the Bronchiectasis Severity Index (BSI).

OBJECTIVE

To describe the etiology of NCFB and compare the results of the assessment of NCFB severity obtained via FACED and BSI scores.

METHODS

Retrospective study of demographic and clinical data of a convenience sample of NCFB patients attending the Functional Breathing Re-adaptation appointment at the Pneumology B Unit, University Hospital Center of Coimbra. All patients underwent evaluation of the variables incorporated in the FACED score (FEV1% predicted, age, chronic colonization by Pseudomonas aeruginosa, radiological extent of the disease, and dyspnea) and in the BSI (age, body mass index, FEV1% predicted, hospitalization and exacerbations before study, dyspnea, chronic colonization by P. aeruginosa and other microrganisms, and radiological extent of the disease). Statistical analysis of the data was performed using Microsoft Excel® and IBM SPSS® v23.

RESULTS

The sample included 40 patients, 22 females and 18 males, aged 39-87 years. Regarding the etiology of NCFB, we found: idiopathic (60%), post-infectious (20%), sequelae of pulmonary tuberculosis (12.5%) and primary immunodeficiency related (7.5%). According to the FACED score we found 20 patients (50%) with mild BC, 15 patients (37.5%) with moderate and 5 patients (12.5%) with severe BC. The frequency of patients with low, intermediate and high BSI was 13 (32.5%), 13 (32.5%) and 14 (35%), respectively in relation to derived BSI, Moreover, we observed a weak but statistically significant association between FACED and BSI scores: Fisher's exact test (p=0.004), tau-b de Kendall (0.469; p=0.001). The Kappa test (0.330; p=0.002) also shows us that there is 55% agreement between the two scales.

CONCLUSION

There is a small but significant correlation between the two scales: a tendency is observed for patients to be classified with a higher BSI compared to the FACED score. This can be explained by the fact that BSI (and not FACED) evaluates parameters including BMI, hospitalization and exacerbations before study, chronic colonization by other microorganisms and development of cystic bronchiectasis. Further studies should address how these scores may impact clinical practice.

Genetic diversity of Desmanthus sp accessions using ISSR markers and morphological traits

Desmanthus is a genus of forage legumes with high nutritional value, productive potential, and ability to obtain nitrogen in association with diazotrophic bacteria. The use of accurate techniques for genotype identification and characterization is essential for breeding programs. Morphological markers are widely used to know the genetic diversity and the molecular markers are fundamental in these studies. We investigated the genetic diversity among Desmanthus sp genotypes in Pernambuco (Brazilian Northeast State), using morphological traits and ISSR markers. Morphological and molecular characterizations were performed in 18 and 26 accessions, respectively, in plants belonging to the germplasm bank of forage legumes of Universidade Federal Rural de Pernambuco (UFRPE), Academic Unit of Serra Talhada, PE, Brazil. Eight ISSR primers were selected, and 95 loci were generated, with polymorphism of 95.79%. The allele number observed was 1.958, where the effective number was 1.359, and the Nei diversity genetic index was 0.226. About the morphological markers, seed number was the variable that most contributed to the genetic divergence. A large amount of genetic diversity was observed among Desmanthus species, occurring spontaneously in Pernambuco, Brazil. Thus, the variability found in morphological and ISSR markers is importance for the improvement of Desmanthus spp. Our findings showed that 17L, 27L, 25F, 22F, 19S, 13Au, and 28G accessions could be used in breeding programs to explore the maximum genetic divergence.

Optimization of biogas production from Sargassum sp. using a design of experiments to assess the co-digestion with glycerol and waste frying oil

A design of experiments was adopted to assess the optimal conditions for methane production from the macroalgae Sargassum sp. co-digested with glycerol (Gly) and waste frying oil (WFO). Three variables were tested: % total solids of algae (%TSSargassumsp.), co-substrate concentration (gGly/WFOL(-1)), and co-substrate type (Gly or WFO). The biochemical methane potential (BMP) of Sargassum sp. was 181±1L CH4kg(-1) COD. The co-digestion with Gly and WFO increased the BMP by 56% and 46%, respectively. The methane production rate (k), showed similar behaviour as the BMP, increasing 38% and 19% with Gly and WFO, respectively. The higher BMP (283±18L CH4kg(-1) COD) and k (65.9±2.1L CH4kg(-1) CODd(-1)) was obtained in the assay with 0.5% TS and 3.0gGlyL(-1). Co-digestion with glycerol or WFO is a promising process to enhance the BMP from the macroalgae Sargassum sp.

Design of experiments to assess pre-treatment and co-digestion strategies that optimize biogas production from macroalgae Gracilaria vermiculophylla

A design of experiments was applied to evaluate different strategies to enhance the methane yield of macroalgae Gracilaria vermiculophylla. Biochemical Methane Potential (BMP) of G. vermiculophylla after physical pre-treatment (washing and maceration) reached 481±9 L CH4 kg(-1) VS, corresponding to a methane yield of 79±2%. No significant effects were achieved in the BMP after thermochemical pre-treatment, although the seaweeds solubilisation increased up to 44%. Co-digestion with glycerol or sewage sludge has proved to be effective for increasing the methane production. Addition of 2% glycerol (w:w) increased the BMP by 18%, achieving almost complete methanation of the substrate (96±3%). Co-digestion of seaweed and secondary sludge (15:85%, TS/TS) increased the BMP by 25% (605±4 L CH4 kg(-1) VS) compared to the seaweed individual digestion.

Quantitative image analysis for the characterization of microbial aggregates in biological wastewater treatment: a review

Quantitative image analysis techniques have gained an undeniable role in several fields of research during the last decade. In the field of biological wastewater treatment (WWT) processes, several computer applications have been developed for monitoring microbial entities, either as individual cells or in different types of aggregates. New descriptors have been defined that are more reliable, objective, and useful than the subjective and time-consuming parameters classically used to monitor biological WWT processes. Examples of this application include the objective prediction of filamentous bulking, known to be one of the most problematic phenomena occurring in activated sludge technology. It also demonstrated its usefulness in classifying protozoa and metazoa populations. In high-rate anaerobic processes, based on granular sludge, aggregation times and fragmentation phenomena could be detected during critical events, e.g., toxic and organic overloads. Currently, the major efforts and needs are in the development of quantitative image analysis techniques focusing on its application coupled with stained samples, either by classical or fluorescent-based techniques. The use of quantitative morphological parameters in process control and online applications is also being investigated. This work reviews the major advances of quantitative image analysis applied to biological WWT processes.

Effects of pre-treatment and bioaugmentation strategies on the anaerobic digestion of chicken feathers

Anaerobic digestion of raw chicken feather waste and its co-digestion with poultry litter were assessed in batch assays. Following, two strategies were evaluated to improve methane production from chicken feathers: (i) waste pre-hydrolysis through thermochemical treatment using lime and sodium hydroxide, and (ii) amendment of digestion broth with the proteolytic bacterium Fervidobacterium pennivorans. Anaerobic digestion of the raw waste (2.5% total solids) allowed a specific methane production of 123 ± 3 L CH(4) kg(-1) VS. Pre-treatment and bioaugmentation strategies did not improve methane production from feather waste, despite the significant increase in waste solubilisation, from 45 ± 5% up to 64 ± 1% using F. pennivorans and up to 96% after pre-treatment with 2g NaOH g(-1) waste. These results indicate that conversion of soluble organic matter to methane, and not the hydrolysis rate, was the limiting step for the anaerobic digestion of chicken feather waste.

Evaluation of the biomethane potential of solid fish waste

Manufacturing processes in fish canning industries generate a considerable amount of solid waste that can be digested anaerobically. The aim of this research was to study the biochemical methane potential of different solid fish waste. For tuna, sardine and needle fish waste, around 0.47g COD-CH(4)/g COD(added) was obtained in batch experiments with 1%TS; whereas for mackerel waste, the methane production attained 0.59g COD-CH(4)/g COD(added). The increase in the waste/inoculum ratio, from 1.1-1.3 to 2.8-3.3g VS(waste)/g VS(inoculum), led to overload due to VFA and LCFA accumulation. Afterward, co-digestion assays of fish waste with gorse were undertaken but the biochemical methane potential did not improve.

Biomethanation potential of macroalgae Ulva spp. and Gracilaria spp. and in co-digestion with waste activated sludge

Biochemical methane potential of four species of Ulva and Gracilaria genus was assessed in batch assays at mesophilic temperature. The results indicate a higher specific methane production (per volatile solids) for one of the Ulva sp. compared with other macroalgae and for tests running with 2.5% of total solids (196±9 L CH(4) kg(-1)VS). Considering that macroalgae can potentially be a post treatment of municipal wastewater for nutrients removal, co-digestion of macroalgae with waste activated sludge (WAS) was assessed. The co-digestion of macroalgae (15%) with WAS (85%) is feasible at a rate of methane production 26% higher than WAS alone without decreasing the overall biodegradability of the substrate (42-45% methane yield). The use of anoxic marine sediment as inoculum had no positive effect on the methane production in batch assays. The limiting step of the overall anaerobic digestion process was the hydrolysis.

Thermochemical pre- and biological co-treatments to improve hydrolysis and methane production from poultry litter

The biochemical methane potential (BMP) of raw poultry litter waste was assessed in batch assays. Biological co-treatment with Clostridium cellulolyticum, Caldicellulosiruptor saccharolyticum and Clostridium thermocellum as bioaugmentation strains, and thermochemical pre-treatments with lime and sodium hydroxide performed at different temperatures and pressures were applied as strategies to improve the BMP by favouring the hydrolysis of the cellulolytic material in the waste. Anaerobic digestion of the raw waste allowed a specific methane production of 145 ± 14 LCH(4)kg(-1)VS, with 1% total solids and 0.72 g VS(inoculum)g(-1)VS(waste). The pre- and co-treatments contributed to a significant increase (up to 74%) in the waste solubilisation when using C. saccharolyticum, but methane production did not improve considerably. Therefore, the conversion of soluble organic matter to methane was the limiting step of the anaerobic digestion process of poultry litter waste.

Strategies for lipids and phenolics degradation in the anaerobic treatment of olive mill wastewater

Strategies are proposed for the anaerobic treatment of lipid and phenolic-rich effluents, specifically the raw olive mill wastewater (OMW). Two reactors were operated under OMW influent concentrations from 5 to 48 g COD L(-1) and Hydraulic Retention Time between 10 and 5 days. An intermittent feeding was applied whenever the reactors showed a severe decay in the methane yield. This strategy improved the mineralization of oleate and palmitate, which were the main accumulated Long-Chain Fatty Acids (LCFA), and also promoted the removal of resilient phenolic compounds, reaching remarkable removal efficiencies of 60% and 81% for two parallel reactors at the end of a feed-less period. A maximum biogas production of 1.4m(3)m(-3)d(-1) at an Organic Loading Rate of 4.8 kg COD m(-3)d(-1) was obtained. Patterns of individual LCFA oxidation during the OMW anaerobic digestion are presented and discussed for the first time. The supplementation of a nitrogen source boosted immediately the methane yield from 21 and 18 to 76 and 93% in both reactors. The typical problems of sludge flotation and washout during the anaerobic treatment of this oily wastewater were overcome by biomass retention, according to the Inverted Anaerobic Sludge Blanket (IASB) reactor concepts. This work demonstrates that it is possible to avoid a previous detoxification step by implementing adequate operational strategies to the anaerobic treatment of OMW.

Morphology and physiology of anaerobic granular sludge exposed to an organic solvent

The use of quantitative image analysis techniques, together with physiological information might be used to monitor and detect operational problems in advance to reactor performance failure. Industrial organic solvents, such as White Spirit, are potentially harmful to granular sludge. In preliminary batch assays, 33 mg L(-1) of solvent caused 50% relative biomass activity loss. In an expanded granular sludge blanket reactor fed with 40 mg L(-1) of solvent, during 222h, the reactor performance seemed to be unaffected, presenting COD removal efficiency consistently >95%. However, in the last days of exposure, the biogas production and the methane content were inhibited. Afterwards, already during recovery phase, the COD removal efficiency decreased to 33%, probably because the reactor was underloaded and the biomass became saturated in solvent only at this stage. In the first hours of exposure the specific acetoclastic and the specific hydrogenotrophic methanogenic activities decreased 29% and 21%, respectively. The % of aggregates projected area with equivalent diameter (D(eq))>1mm decreased from 81% to 53%. The mean D(eq) of the aggregates > or =0.2mm decreased, as well as the settling velocity, showing that the granules experienced fragmentation phenomenon caused by the solvent shock load. The ratio between total filaments length and total aggregates projected area (LfA) increased 2 days before effluent volatile suspended solids, suggesting that LfA could be an early-warning indicator of washout events.

Principal component analysis and quantitative image analysis to predict effects of toxics in anaerobic granular sludge

Principal component analysis (PCA) was applied to datasets gathering morphological, physiological and reactor performance information, from three toxic shock loads (SL1 - 1.6 mg(detergent)/L; SL2 - 3.1mg(detergent)/L; SL3 - 40 mg(solvent)/L) applied in an expanded granular sludge bed (EGSB) reactor. The PCA allowed the visualization of the main effects caused by the toxics, by clustering the samples according to its operational phase, exposure or recovery. The aim was to investigate the variables or group of variables that mostly contribute for the early detection of operational problems. The morphological parameters showed to be sensitive enough to detect the operational problems even before the COD removal efficiency decreased. As observed by the high loadings in the plane defined by the first and second principal components. PCA defined a new latent variable t[1], gathering the most relevant variability in dataset, that showed an immediate variation after the toxics were fed to the reactors. t[1] varied 262%, 254% and 80%, respectively, in SL1, SL2 and SL3. The high loadings/weights of the morphological parameters associated with this new variable express its influence in shock load monitoring and control, and consequently in operational problems recognition.

[Infantile hepatic hemangioendothelioma. A multifocal, bilobular and asymptomatic case with spontaneous regression]

Infantile hepatic hemangioendothelioma is a severe disease with a high mortality rate. Nevertheless these vascular lesions may experience spontaneous regression within 12 to 18 months. The decision of trying a specific treatment and the choice among the several therapeutic options remains controversial, particularly in those asymptomatic cases of multifocal, bilobular involvement. We describe a case of multifocal, bilobular and asymptomatic infantile hepatic hemangioendothelioma, untreated, and with spontaneous regression before 2 years of age.

Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge

Due to unspecified operational problems, the specific acetoclastic activity (SAA) of the anaerobic granular sludge present in an industrial UASB reactor was considerably damaged (from 250 to less than 10mL CH(4)@STP/gVSS.d), significantly reducing the biogas production of that industrial unit. The hydrogenotrophic methanogenic activity exhibited a value of 600mL CH4@STP/gVSS.d, the settling velocity was 31.4+/-9.8m/h, the average equivalent diameter was 0.92+/-0.43mm, and about 70% of the VSS were structured in aggregates larger than 1mm. In order to study the recovery of the SAA, this sludge was collected and inoculated in a lab-scale expanded granular sludge blanket (EGSB) reactor. Ethanol was fed as the sole carbon source during a trial period of 106 days. Process monitoring included COD removal efficiency, methane production, and periodic determination of the specific methanogenic activity in the presence of acetate, propionate, butyrate, ethanol and H(2)/CO(2). Quantitative image analysis allowed for information to be obtained on granular fragmentation/erosion and filaments release. During the first operational period, biogas production was mainly due to the hydrogenotrophic activity. However, after 40 days, the SAA steadily increased achieving a maximum value of 183+/-13mL CH4@STP/gVSS.d. The onset of SAA recovery, granules breakdown and filaments release to the bulk occurred simultaneously. Further increase in SAA was accompanied by granular growth. In the last 25 days of operation, the size distribution was stable with more than 80% of projected area of aggregates corresponding to granules larger than 1mm (equivalent diameter). Confocal images from FISH hybridized sections of the granules showed that after SAA recovery, the granules developed an organized structure where an acidogenic/acetogenic external layer was apparent. Granular fragmentation and increase of filaments in the bulk, simultaneously with the increase in the acetoclastic activity are described for the first time and might represent a structural response of granular sludge to promote the optimal substrate uptake at minimal diffusion limitations.

Quantitative image analysis as a diagnostic tool for monitoring structural changes of anaerobic granular sludge during detergent shock loads

Two shock loads of a commercial detergent (I-150 mg chemical oxygen demand (COD)/L, fed for 56 h; II-300 mg COD/L fed for 222 h) were applied in a lab-scale Expanded Granular Sludge Blanket (EGSB) reactor, fed with 1,500 mg COD/L of ethanol. The impact of the surfactant was assessed in terms of granular sludge morphology, specific methanogenic activity (SMA) in the presence of individual substrates, and reactor performance. COD removal efficiency remained unaffected in the shock I, but 80 h after starting exposure to the shock II, the COD removal efficiency decreased drastically from 75 to 17%. In the first 8 h of operation of shock I, the SMA was stimulated and decreased afterwards, being recovered 5 days after the end of exposure time. Concerning to shock II, the SMA was immediately and persistently reduced during the exposure time, although, the inhibition of SMA in presence of H(2)/CO(2) showed a trend to increase after the exposure time. Acetoclastic bacteria were observed as the most sensitive to the toxic effects of surfactant whereas the hydrogenotrophic bacteria were less affected. The inhibitory effects were dependent on surfactant concentration and exposure time. The ratio filaments length per total aggregates area (LfA) was an early-warning indicator of biomass washout, since it increased 3 and 5 days before effluent volatile suspended solids (VSS) rise, respectively, in shocks I and II.

Knowledge-based fuzzy system for diagnosis and control of an integrated biological wastewater treatment process

A supervisory expert system based on fuzzy logic rules was developed for diagnosis and control of a laboratory- scale plant comprising anaerobic digestion and anoxic/aerobic modules for combined high rate biological N and C removal. The design and implementation of a computational environment in LabVIEW for data acquisition, plant operation and distributed equipment control is described. A step increase in ammonia concentration from 20 to 60 mg N/L was applied during a trial period of 73 h. Recycle flow rate from the aerobic to the anoxic module and bypass flow rate from the influent directly to the anoxic reactor were the output variables of the fuzzy system. They were automatically changed (from 34 to 111 L/day and from 8 to 13 L/day, respectively), when new plant conditions were recognised by the expert system. Denitrification efficiency higher than 85% was achieved 30 h after the disturbance and 15 h after the system response at an HRT as low as 1.5 h. Nitrification efficiency gradually increased from 12 to 50% at an HRT of 3 h. The system proved to react properly in order to set adequate operating conditions that led to timely and efficient recovery of N and C removal rates.

Herd-level seroprevalence of fasciolosis in cattle in north central Portugal

An epidemiological study of Fasciola hepatica in cattle was implemented in the north central region of Portugal. Both an enzyme-linked immunosorbent assay and an egg shedding quantification technique were used in the follow-up of seven herds. Two of these herds were negative and the other five were positive for F. hepatica. A herd cut-off of value of 0.425 optical density was calculated and herd sensitivity (HSe) and herd specificity (HSp) were defined. Three seroprevalence studies were also implemented in the region with stratification by county sub-regions for a period of 18 months. Overall mean herd prevalence in Vagos of 11, 23 and 48% was progressively found for the three studies, respectively.

[Color vision in school children: evaluation of a new test]

OBJECTIVE: To compare standard color vision test results (Ishihara test) with a new test developed by the authors ("crayon" test) for the detection of congenital dyschromatopsia. METHODS: Cross-sectional study of 712 children from three public schools and one private school in the city of Porto Alegre, state of Rio Grande do Sul. Children with learning disabilities, or systemic and ocular diseases were excluded from this random sample. Two color vision tests, Ishihara test (short version with 14 plates) and crayon test (developed by the authors) were sequentially applied. Each test was applied by different evaluators and analyzed by a third evaluator. RESULTS: The crayon test showed a specificity of 100% (99.3-100%) and sensitivity of 38.5% (15.1-67.7%) when compared to Ishihara test. The prevalence of congenital dyschromatopsia in this population sample was 2.6% for male children, and 0.9% for female children. CONCLUSIONS: The crayon test results showed greater specificity than Ishihara test in the studied group; however, sensitivity was not adequate for a screening test. It is necessary to improve the sensitivity so that congenital dyschromatopsia can be detected by the crayon test.

[Seizures in the neonatal period]

OBJECTIVE: To characterize and differentiate neonatal seizures from those that occur at different ages, based on a critical assessment of the available literature and also on the authorś clinical experience. SOURCES: Literature review, including up-to-date and classical studies that helped us to better understand clinical, neurophysiological and physiopathological aspects related to seizures in the newborn. SUMMARY OF THE FINDINGS: The authors present clinical and electroencephalographic characteristics of neonatal seizures, discuss their classification, treatment and prognosis. CONCLUSIONS: Neonatal seizures have a distinct clinical pattern, which justifies the necessity of an appropriate classification. The etiology is predominantly symptomatic and multifactorial; the treatment should follow a routine protocol, and the prognosis seems to be closely related to etiology.

The utility of Ki-ras mutation analysis in the cytologic diagnosis of pancreatobiliary neoplasma

PURPOSE

Mutations involved in neoplastic progression may be able to serve as markers for the presence of small numbers of neoplastic cells that would otherwise escape detection in diagnostic assays. Previous retrospective studies have suggested that the sensitivity of the cytologic diagnosis of pancreatic and biliary tract carcinomas is improved when analysis includes Ki-ras exon 1, which is commonly mutated in these neoplasms. We report our experience with the systematic prospective application of Ki-ras gene analysis to the evaluation of fine-needle aspirates and brushings from the pancreatobiliary tract.

MATERIALS AND METHODS

Between September 1996 and April 1999, 75 pancreatic fine-needle aspirates and common bile duct brushings submitted for routine cytologic diagnosis were also evaluated for mutations in Ki-ras exon 1 by polymerase chain reaction/single-strand conformation polymorphism analysis. After routine preparation of the specimens, residual material was used for molecular analysis. Results are compared with the morphologic diagnosis and available clinical information.

RESULTS

Single-strand conformation polymorphism mutation patterns in Ki-ras were detected in 22 of the 70 consecutive clinical specimens with adequate DNA and at least 6 months of available clinical follow-up. Sensitivity, specificity, and positive predictive value for the presence of concurrent or subsequent pancreatobiliary carcinoma were 33%, 97%, and 93%, respectively, for definitive cytologic diagnosis alone, and 53%, 97%, and 95% for positive Ki-ras single-strand conformation polymorphism mutation pattern alone. If definitive positive cytology or atypical/suspicious cytology with a positive Ki-ras single-strand conformation polymorphism mutation pattern is used, sensitivity is 55%, specificity is 97%, and positive predictive value is 96% for the presence of pancreatobiliary carcinoma.

DISCUSSION

Results support the routine use of Ki-ras mutational analysis to increase the sensitivity of the cytologic evaluation of pancreatobiliary fine-needle aspirates and common bile duct brushings with atypical or suspicious morphology without compromising specificity.

Magnetic resonance cholangiopancreatography: comparison between respiratory-triggered turbo spin echo and breath hold single-shot turbo spin echo sequences

The purpose of this study was to compare the relative conspicuity of the pancreaticobiliary tree on respiratory-triggered three-dimensional turbo spin echo (3D TSE RT) and breath hold single-shot turbo spin echo (SSTSE BH) acquisitions respectively in MRCP imaging. Both techniques were applied to 61 patients with clinically suspected pancreaticobiliary disease using a 1.0 T MR system. All images were reviewed blindly. Qualitative comparison was made by grading subjectively the conspicuity of extrahepatic, intrahepatic, and main pancreatic ducts. Quantitative comparison included calculations of signal-to-noise ratio of the common bile duct, main pancreatic duct, gallbladder, liver, and contrast-to-noise ratio, relative contrast between common bile duct, gallbladder, and liver. 3D TSE RT provided significantly higher signal-to-noise ratio of the common bile duct (mean value 163.19) and main pancreatic duct (mean value 95.37) compared to SSTSE BH (mean values 76.24 and 26.22, respectively). 3D TSE RT was inferior to SSTSE BH for the depiction of intrahepatic ducts and pancreatic duct (head portion). 3D TSE RT and SSTSE BH sequences provide complimentary information in the visualization of the biliary and pancreatic ducts. Further comparative clinical studies are needed to redefine the sensitivity, specificity, and accuracy of MRCP using both sequences.

[Associated and prognosis in apparent life threatening events (ALTE)]

OBJECTIVE: To verify the etiology and prognosis of ALTE in infancy and its possible relationship to Sudden Infant Death Syndrome (SIDS). METHODS: We studied a group of infants that presented ALTE episodes and were evaluated in our hospital. First we reviewed their clinical history and polysomnographies, then we sent a letter to the families with questions regarding the outcome. RESULTS: 56 patients were included. 92% had ALTE during their first 6 months and 83% in the first trimester. Symptomatic ALTE predominated (71%). The disease most frequently associated was gastroesophageal reflux, followed by neurological diseases. The follow up showed 51.5% of normal outcome, 4 children repeated ALTE, no cases of SIDS were registered. CONCLUSIONS: Our results showed that multifactorial etiologies can be associated to ALTE, and the outcome is generally related to the associated disease. We did not observe any relationship between ALTE and SIDS considering a predominantly symptomatic ALTE population.

Posttraining administration of substance P and its N-terminal fragment block the amnestic effects of diazepam

This study examined the effects of posttraining administration of substance P (SP) and of certain N- or C-terminal SP-fragments on retention performance of rats treated with diazepam (DZP). Twenty minutes before the training on an inhibitory avoidance task rats were given intraperitoneal injections of either DZP (2 mg/kg) or vehicle. Immediately after they were injected with SP (50 micrograms/kg), SPN 1-7 (167 micrograms/kg), SPC 6-11 (134 micrograms/kg), or vehicle. The posttrial administration of SP and SPN, but not SPC, facilitated avoidance behavior. Animals that received DZP before training and vehicle after the conditioning trial showed impaired retention. In contrast, in animals injected with SP and SPN after the training trial, DZP did not affect retention. These findings suggest that the amnestic effects of DZP can be blocked by the administration of SP and that the amino acid sequence responsible for this effect may be encoded by its N-terminal part.

Effects of immunotherapy on symptoms, PEFR, spirometry, and airway responsiveness in patients with allergic asthma to house-dust mites (D. pteronyssinus) on inhaled steroid therapy

The present study was designed to investigate the effects of immunotherapy (IT) with an extract of Dermatophagoides pteronyssinus (Alergo-Merck Depot) during a 27-month period in patients with allergic asthma to house-dust mites. We included 11 patients (mean age 18 years) treated with a combination of IT and inhaled beclomethasone dipropionate (BDP) in comparison to another 11 (mean age 22 years) treated with BDP alone. We evaluated symptom scores, salbutamol use, peak expiratory flow rates (PEFR), spirometry, and bronchial hyperresponsiveness (BHR) during 18 months of therapy with BDP and in the 9 months after BDP interruption. The two kinds of treatment were efficient and comparable in relation to symptom score, salbutamol use, morning PEFR, FVC, and FEV1, but patients treated with IT and BDP had a faster improvement of BHR and PEFR variability. The interruption of BDP after 18 months of therapy was linked to an impairment of all end points, which were more pronounced in patients previously treated only with BDP. These findings suggest that in selected asthmatic patients allergic to house-dust mites, the association of IT and BDP is more effective than therapy with this inhaled steroid alone due to a faster and more striking improvement during the first months of treatment and to a lower rate of relapse after the interruption of therapy with BDP.

CT identification of ascaris in the biliary tract

Ascariasis is one of the most common helminthic diseases worldwide. The presence of this worm in the biliary tree causes biliary colic, recurrent pyogenic cholangitis, pancreatitis, hepatic abscesses, and septicemia. The diagnosis of biliary ascariasis is usually made by ultrasound (US). We report the computerized-tomography (CT) aspects that allowed the identification of ascaris in the biliary tract in two patients.

Paraganglioma of the spermatic cord. Report of a case with immunohistochemical and ultrastructural studies

We describe a case of paraganglioma arising in the spermatic cord, which is an extremely rare location. Immunohistochemical studies characterized two types of cells: (1) polygonal cells expressing neuron-specific enolase, chromogranin A, and synaptophysin and (2) S100 protein-positive sustentacular cells. Electron microscopy revealed that within the cytoplasm of the polygonal cells, there were electron-dense granules whose morphological appearance was consistent with that of neurosecretory granules. Paraganglioma of the spermatic cord may originate from embryonic chromaffin cells that have followed the testis into the scrotum.

Modifications of the responses of barrel field neurons to vibrissal stimulation during theta in the awake and undrugged rat

In partially restrained but awake and undrugged rats, excitatory unit responses of the somatic cortex barrel field to vibrissal stimulation, were recorded in two conditions: during spontaneous episodes of theta and in the absence of this rhythm. Two main variables were considered: a signal-to-noise ratio and an index of the "afferent inhibition". Both measures were extracted from peristimulus time histograms. "Theta effects" were characterized by an increase in signal-to-noise ratio and afferent inhibition. They were most important in neurons located in infragranular layers of the cortex; they went in the same direction but only approached significance in supragranular neurons; neurons of the granular layer were not affected. Spontaneous unit activity and latencies were not modified in any group. These data were obtained during a preliminary step of a sensory-sensory conditioning procedure which in some cases modified the receptive field of the neurons. Theta effects were less marked in future "conditioned" than in future non-conditioned neurons but this was probably due to the fact that conditioned neurons had significantly higher signal-to-noise ratio and afferent inhibition. The origin of these "theta effects", hippocampal versus non-hippocampal, and their functional significance, relation to selective attention, are discussed.

Evidence for a cholinergic mechanism of "learned" changes in the responses of barrel field neurons of the awake and undrugged rat

Due to its functional importance and its large and highly differentiated central projections, the vibrissal system of rodents is a prime object for the study of sensory plasticity, especially at the cortical level: the representation of vibrissae in the "barrel field", a part of the somatic cortex, is exceptionally precise and is susceptible to experience-induced changes. In a previous series of experiments, we found that a sensory-sensory conditioning procedure, pairing two vibrissal stimulations, produces significant changes in responses of single neurons of the barrel field in the chronic awake and undrugged rat: (1) the appearance of an excitatory response to a stimulus that was ineffective before pairing ("conditioned response"); (2) the modifications of pre-existing responses consisting of the suppression of afferent inhibition and the appearance of long-latency excitatory components. We report here that the micro-iontophoretic application of atropine abolishes "conditioned responses" and restores afferent inhibition. Acetylcholine facilitates an enlargement of the receptive field and induces a sustained mode of discharge to stimuli. These data provide a new and direct support to the hypothesis that cholinergic mechanisms are involved in the sensory cortex plasticity.

A new one-trial test for neurobiological studies of memory in rats. II: Effects of piracetam and pramiracetam

The effects of the nootropic drugs Piracetam (Pir) and Pramiracetam (Pram) were evaluated on recognition-memory of rats in a new one-trial test. This test is based on spontaneous exploratory activity and does not involve rule learning or reinforcement. Recognition is measured by the time spent by rats in exploring two different objects, one familiar (the sample), the other new. When the retention interval is 1 min, normal rats spend more time exploring the new object which demonstrates that they recognize the familiar one, but they do not discriminate between the two objects after a 24-h interval. Three doses of Pram (15, 30 and 60 mg/kg) and Pir (100, 200 and 400 mg/kg) were administered i.p. 30 min before the acquisition trial. The doses of 30 mg/kg of Pram and of 400 mg/kg of Pir produced a significant improvement in retention when the intertrial interval was 24 h. This effect was not associated with a change in overall exploratory behavior. This study shows that the new object-recognition test may be a useful tool for pharmacological studies of memory in rats.

d-Amphetamine enhances memory performance in rats with damage to the fimbria

Rats were preoperatively trained on a 5-unit linear maze and were then subjected to fimbria lesions. The animals were then retested on the same task with one group of rats with fimbria lesions and a control group being injected daily with 0.5 mg/kg d-amphetamine sulfate prior to testing. Lesions significantly impaired postoperative performance of the task, while amphetamine facilitated performance in fimbria lesioned rats. Due to an optimal learning of the task, performance of control animals was not significantly facilitated. These results raise several important issues including the mechanisms of functional recovery after brain lesions and the role of the hippocampal formation in learning and memory.

Quantitation of immunoglobulin A in the human chorioamniotic membrane

Thirty-eight chorioamniotic membranes were obtained from normal patients divided into three groups according to time of rupture. A protein extract was obtained by destruction and differential centrifugation and immunoglobulin A was measured by the method of Mancini. The authors demonstrated that it is possible to quantitate immunoglobulin A. No statistically significant differences were observed between groups.

Demonstration of the presence of IgA in the human chorioamniotic membrane

The presence of IgA was detected by direct immunofluorescence techniques in the chorion and decidua of eight fragments of chorioamniotic membranes obtained near the rupture edge from eight normal patients. It is suggested that, similar to what occurs in other organic systems, a first barrier against infection of the amniotic chamber exists at this site.

Murine type C retroviruses and intracisternal A-particles in human tumors serially passaged in nude mice

An ultrastructural survey of 11 human tumors passaged in N:NIH(S) (nu/nu) mice showed two instances of type C virus production. In one instance type C virus particles were observed in the endothelial murine stromal cell component of an embryonal carcinoma but not in the human tumor cells. In another instance type C virus particles were seen replicating in the chondroblastic human cells of a xenografted osteosarcoma. The type C virus produced in the human cells failed to transform NIH/3T3 cells, the C-127 rat cell line, or mink cells. Nucleic acid hybridization studies in which a human endogenous retroviral probe and a xenotropic murine leukemia virus envelope probe were used suggested that the retrovirus present in the human osteosarcoma cells is related to murine leukemia viruses. Intracisternal A-particles (IAP) were also detected in the human osteosarcoma cells. Their presence in the human cells was demonstrated by simultaneous visualization of IAP and human HLA determinants at the cell surface. The literature on type C virus infection of human cells and tumors grafted in nude mice is reviewed.

"Low grade" mucoepidermoid carcinoma of the bronchus with "high grade" biological behavior

A case of mucoepidermoid carcinoma of the bronchus with low grade histologic features exhibited an aggressive biological behavior. All gross, microscopic, and ultrastructural features were those of a morphologically low grade mucoepidermoid carcinoma. Grossly, the lesion was an exophytic endobronchial mass; microscopically, it contained sheets of monomorphic cells with well-formed mucus glands, no mitoses, and no necrosis; and ultrastructurally, it consisted of numerous goblet cells and mitochondria- and glycogen-rich cells with well-formed microvilli. However, the patient developed widespread metastases to skin, subcutaneous tissue, femur, vertebral column, and pericardium and died two months after the primary endobronchial tumor was excised. The metastases, like the primary tumor, had the appearance of "low grade" mucoepidermoid carcinoma. Explants of the original tumor grown in nude mice for three months showed persistence of the low-grade morphologic pattern. Although metastases are known to occur frequently from high-grade lesions, widespread metastases from histologically low-grade lesions have not previously been reported. Low-grade histologic features of mucoepidermoid carcinoma are not necessarily then indicative of low-grade biological behavior.

Renal cell carcinoma and systemic amyloidosis: demonstration of AA protein and review of the literature

A case of renal cell carcinoma associated with systemic amyloidosis in a patient with nephrotic syndrome is presented. Amyloid deposits were present in the resected tumor, ipsilateral kidney, and spleen. Potassium permanganate treatment of histologic sections as well as immunoperoxidase staining identified AA protein within the amyloid. Surgical removal of the tumor caused marked remission of the patient's proteinuria. Thirty-nine previously reported cases of renal cell carcinoma with amyloidosis are reviewed. Most tumors have clear cell histologic features, and the amyloid distribution follows the "secondary" pattern. A possible mechanism of amyloid production in renal cell carcinoma is presented in which the tumor directly or indirectly participates in the modification of SAA protein into a precipitable form.

[Operant conditioning with thermal reinforcement in the newborn rat]

In previous experiments, we studied the acquisition of instrumental locomotor responses reinforced by thermal stimuli, in one to ten-day-old rats. In these tasks, there was a precise topographic relation between the behavior to be conditioned and the reinforcement. In the experiment reported in the present paper, one to eight-day-old rats were tested in an operant conditioning task, where the operant (OP) was a non locomotor behavior, the raising of the head. At each day of age, two paired groups were compared: a "contingent" (C) and a "non contingent" (NC) group. Each OP (satisfying an amplitude criterion) of a C rat was reinforced by the application of a 30-35 degrees C air-stream during ten seconds. The NC rat of the same pair received the same number of air-streams during the session, but these stimuli were unrelated to its behavior. The duration of the session was ten minutes. Mean frequency of OP was higher in C than in NC groups, at one, two, six, seven and eight day of age. Absence of significant differences between C and NC groups at three, four and five days of age could be due to the competition between OP and the emerging locomotor behavior.

[Spatial discrimination with thermal reinforcement in the young rat. (author's transl)]

Infant rats, because of their deficient thermoregulation, are very reactive to thermal stimuli. In our experiences, four to ten day old animals were trained a discriminative locomotor response between two places of a symmetrical device. A correct choice was reinforced by a 30-35 degree air stream during twenty seconds. One hundred and forty Wistar rats (male and female) were submitted to a twenty trial acquisition session (intertrial interval = 20 seconds). Those who reached a 70% correct criterion were trained to reverse their initial discrimination. Spontaneous alternation and "vicarious trial and errors" (VTE) were systematically observed. Percentages of correct responses in the two tests increased with age and reached a maximum in nine and ten day old rats. This increase was mainly due to a decrease of percentages of incorrect responses. Spontaneous alternation rate also progressed with age but did not reach adult level. VTE appeared in nine day old rats and were highly positively correlated with correct responses.

Meyenburg complexes of the liver and bile cysts as a consequence of hepatic ischemia

Meyenburg complexes and simple bile cysts are described in a patient having polyarteritis nodosa with involvement of the intrahepatic arterial tree. Similar lesions are found in the liver of monkeys subjected to experimental occlusion of the peripheral hepatic arterial tree. It is proposed that a pathogenetic mechanism conducive to the formation of Meyenburg complexes may be hepatic ischemia.

Plasma lipid concentrations for some Brazilian lizards

1. Plasma concentrations of cholesterol, cholesteryl esters, phospholipids and triglycerides were determined for ten species of Brazilian lizards, Iguana iguana, Tropidurus torquatos and T. semitaeniatus (Iguanidae), Tupinambis teguixin, Ameiva ameiva and Cnemidophorus ocellifer (Teiidae), Mabuya maculata (Scincidae), Hemidactylus mabouia (Gekkonidae), Amphisbaenia vermicularis and Leposternon polystegum (Amphisbaenidae). 2. Considerable inter- and intra-species variations in plasma lipid concentrations were observed. 3. The percentage of total cholesterol esterified and the individual phospholipid composition of plasma were relatively constant for each species. 4. Over 60% of the cholesteryl esters present in plasma from three species each of iguanid and teiid lizards were polyenoic.

Determination of lecithin:cholesterol acyltransfer in mouse plasma and the influence of mercaptoethanol and sulphydryl blocking agents on its activity

1. The cholesterol esterifying activity in mouse plasma has been identified as lecithin:cholesterol acyltransferase (LCAT) on the basis of stoichiometric data, predominant transfer of polyunsaturated fatty acids, wide pH optimum and inhibition of esterification by phospholipase A2 and sulphydryl blocking agents. The esterifying activity differed from that present in plasma of man, rat and other species since it was partially inhibited by mercaptoethanol and other thiols. 2. Stoichiometric correlations between unesterified cholesterol, lecithin and lysolecithin were not exact, suggesting possible involvement of other enzymes in the overall esterification process during in vitro incubation of mouse plasma. 3. The initial rate of cholesterol esterification was determined by in vitro incubation of mouse plasma, whose cholesterol had been labelled by prior in vivo injection of 3H-mevalonic acid. The mean rate was 281 +/- 74 nmol/ml/hr (mean +/- S.D., n = 12) and correlated with unesterified cholesterol concentration (r = 0.73, P less than 0.01).