Reliability of the serial reaction time task: If at first you don't succeed, try, try, try again

Procedural memory is involved in the acquisition and control of skills and habits that underlie rule and procedural learning, including the acquisition of grammar and phonology. The serial reaction time task (SRTT), commonly used to assess procedural learning, has been shown to have poor stability (test-retest reliability). We investigated factors that may affect the stability of the SRTT in adults. Experiment 1 examined whether the similarity of sequences learned in two sessions would impact stability: test-retest correlations were low regardless of sequence similarity (r < .31). Experiment 2 added a third session to examine whether individual differences in learning would stabilise with further training. There was a small (but nonsignificant) improvement in stability for later sessions (Sessions 1 and 2: r = .42; Sessions 2 and 3: r = .60). Stability of procedural learning on the SRTT remained suboptimal in all conditions, posing a serious obstacle to the use of this task as a sensitive predictor of individual differences and ultimately theoretical advance.

Exposure of insects and host plants to different concentrations of CO2 affects the performance of Mahanarva spectabilis (Hemiptera: Cercopidae) in successive insect generations

The performance of three successive generations of Mahanarva spectabilis (Distant) (Hemiptera: Cercopidae) fed on four forages exposed to environments with different CO2 concentrations was evaluated. In the first bioassay, we utilized the following scenarios: A) plants and insects were kept at high and constant CO2 (700 ppm) and B) the insects were kept at CO2 700 ppm and fed on plants from the greenhouse (average of 390 ppm). In the second bioassay, we utilized the following scenarios: C) plants and insects were kept in a greenhouse and D) the insects were kept in the greenhouse and fed on plants kept at CO2 700 ppm. The survival and duration of the nymphal and adult stages and the number of eggs/female of M. spectabilis were evaluated. It was only possible to evaluate the cumulative effects of the increase of CO2 on three successive generations of M. spectabilis kept in a greenhouse, due to the reduced survival of the insects in the first generation in the laboratory. A greater direct than indirect effect of the CO2 level on the performance of M. spectabilis was observed. Furthermore, it should be considered that the effect of CO2 elevation on the survival, periods of development, and fecundity, when taken together, can significantly impact the population dynamics of M. spectabilis in future climate scenarios.

Limited Evidence of an Association Between Language, Literacy, and Procedural Learning in Typical and Atypical Development: A Meta-Analysis

The ability to extract patterns from sensory input across time and space is thought to underlie the development and acquisition of language and literacy skills, particularly the subdomains marked by the learning of probabilistic knowledge. Thus, impairments in procedural learning are hypothesized to underlie neurodevelopmental disorders, such as dyslexia and developmental language disorder. In the present meta-analysis, comprising 2396 participants from 39 independent studies, the continuous relationship between language, literacy, and procedural learning on the Serial Reaction Time task (SRTT) was assessed across children and adults with typical development (TD), dyslexia, and Developmental Language Disorder (DLD). Despite a significant, but very small, relationship between procedural learning and overall language and literacy measures, this pattern was not observed at the group-level when examining TD, dyslexic, and DLD groups separately. Based on the procedural/declarative model, a positive relationship was expected between procedural learning and language and literacy measures for the typically developing group; however, no such relationship was observed. This was also the case for the disordered groups (ps > .05). Also counter to expectations, the magnitude of the relationship between procedural learning and grammar and phonology did not differ between TD and DLD (ps > .05), nor between the TD and dyslexic group on reading, spelling, and phonology (ps > .05). While lending little support to the procedural/declarative model, we consider that these results may be the consequence of poor psychometric properties of the SRTT as a measure of procedural learning.

The reliability of the serial reaction time task: meta-analysis of test-retest correlations

The Serial Reaction Time task, one of the most widely used tasks to index procedural memory, has been increasingly employed in individual differences research examining the role of procedural memory in language and other cognitive abilities. Yet, despite consistently producing robust procedural learning effects at the group level (i.e. faster responses to sequenced/probable trials versus random/improbable trials), these effects have recently been found to have poor reliability. In this meta-analysis (N = 7), comprising 719 participants (M = 20.81, s.d. = 7.13), we confirm this 'reliability paradox'. The overall retest reliability of the robust procedural learning effect elicited by the SRTT was found to be well below acceptable psychometric standards (r < 0.40). However, split-half reliability within a session is better, with an overall estimate of 0.66. There were no significant effects of sampling (participants' age), methodology (e.g. number of trials, sequence type) and analytical decisions (whether all trials were included when computing the procedural learning scores; using different indexes of procedural learning). Thus, despite producing robust effects at the group-level, until we have a better understanding of the factors that improve the reliability of this task using the SRTT for individual differences research should be done with caution.

Patients' perspectives of the skills and competencies of therapy radiographers/radiation therapists (TRs/RTTs) in the UK, Portugal and Malta; a qualitative study from the SAFE Europe project

INTRODUCTION

The role of the Therapy Radiographer/Radiation Therapist (TR/RTT) is to provide radiotherapy to patients with a cancer diagnosis. This includes, not only administration of treatment, but also management of side-effects and provision of support/care. Despite this role being consistent throughout Europe, there is currently no standardisation of education for TRs/RTTs. The SAFE EUROPE project aims to standardize TR/RTT education to enable 'safe and free exchange' of TRs/RTTs across Europe. Consequently, this study aims to explore patients' perspectives regarding the current skills and competencies of TRs/RTTs.

METHODS

From May 2021 to February 2022, semi-structured interviews were conducted with patients who had recently received radiotherapy in the UK, Malta and Portugal. Ethical approval for this study was granted by the NHS Research Ethics Committee with additional local approvals obtained.

RESULTS

Forty-eight participants from the UK (n = 18), Portugal (n = 19), and Malta (n = 11) completed interviews. Participants described high satisfaction with TRs'/RTTs' competence and skills in all three countries. The main theme arising from the analysis was the importance of trust building with TRs/RTTs. Six factors were identified as influencing levels of trust: communication; side-effect management; team consistency; relational skills; patient dignity; and competence. A small number of patients reported feeling rushed and not having their physical and emotional needs met by TRs/RTTs.

CONCLUSION

This multicentre study demonstrated that patients perceive TRs/RTTs in the UK, Malta and Portugal as highly competent and skilled. Practical recommendations are provided to address identified deficits in practice, which can be addressed through adaptation of TR/RTT education/training and clinical practice.

IMPLICATIONS FOR PRACTICE

Recommendations arising from this study are important to ensure that TRs/RTTs have transferable skills that provide consistently high quality care to patients throughout Europe.

Pain Intensity and Sexual Functioning in Men with Genital Pain: The Mediation Role of Sexually Related Thoughts

The comorbidity between male genital pain and sexual dysfunction is highly prevalent. Previous studies have indicated that men with genital pain share some cognitive characteristics with men experiencing other sexual dysfunctions. However, there is little information on the role of these cognitive factors in understanding the relationship between pain intensity and sexual functioning. This study aims to test if negative sexually related thoughts mediate the relationship between pain intensity and sexual functioning in men with genital pain. A total of 50 men with self-reported genital pain completed an online survey assessing pain intensity, thoughts during sexual activity, and sexual functioning. Results showed a significant effect of negative sexually related thoughts on sexual functioning, β = -.71, t(50) = -4.2, p <.001. Additionally, the Sobel test found a partial mediation effect (z = 2.23, p =.025) and a medium to large indirect effect size was observed (ab_cs =.474). Findings suggest that negative sexually related thoughts play an important role in explaining the impact of pain intensity on sexual functioning. Overall, the study emphasizes the relevance of cognitions in predicting sexual function/dysfunction in men with genital pain and suggests the use of cognitive techniques in the treatment of this clinical condition.

Coffee berry borer in conilon coffee in the Brazilian Cerrado: an ancient pest in a new environment

The aim of this study was to verify the occurrence of the coffee berry borer, Hypothenemus hampei (Ferrari), and to evaluate the population fluctuation of the pest in the Brazilian Cerrado (Federal District). The study was conducted, between November 2014 and October 2015, at Embrapa Cerrados (Planaltina/DF, Brazil) in an irrigated conilon coffee production area. In November 2014, 120 samples (ten berries/sample) were collected from berries that had fallen on the ground from the previous harvest. Between November 2014 and October 2015, insects were collected weekly, using traps (polyethylene terephthalate bottles) baited with ethyl alcohol (98 GL), ethyl alcohol (98 GL) with coffee powder, or molasses. Between January and July 2015, samples were collected fortnightly from 92 plants (12 berries per plant). All samples were evaluated for the presence of adult coffee berry borers. Samples from the previous harvest had an attack incidence of 72.4%. The baited traps captured 4062 H. hampei adults, and showed no statistical difference in capture efficiency among the baits. Pest population peaked in the dry season, with the largest percentage of captured adults occurring in July (31.0%). An average of 18.6% of the collected berries was attacked by the borer and the highest percentage incidence was recorded in July (33.2%). Our results suggest that the coffee berry borer, if not properly managed, could constitute a limiting factor for conilon coffee production in the Brazilian Cerrado.

Measuring population fluctuation of jatropha stem-borer [Cophes notaticeps (Marshall)] in the Brazilian Cerrado using a new trap

This study aimed to monitor the population fluctuation of Cophes notaticeps (Marshall) (Coleoptera: Curculionidae) in a jatropha (Jatropha curcas L.) plantation in the Federal District, Brazil, through the use of a new trap, combined with different attractive lures and trap colors. The study was conducted at Embrapa Cerrados (Planaltina/DF) in a field trial with 720 plants. The new trap, named CPAC16, was made with PVC pipes (100 mm in diameter) of about 40 cm in length, with a window (8 × 10 cm2) in its center to enable insect access. A lure compartment was fixed on the inside of the trap`s top, and a pot, containing water and detergent, was placed at its bottom to collect the insects. The traps were painted in red, yellow, blue and green. Molasses, ethanol and pineapple were used as attractive lures. The traps were in the field trial area between May 2013 and April 2014 and the insects were collected weekly. The incidence of plants presenting damage caused by C. notaticeps was evaluated in the beginning and at the end of the study. The CPAC16 trap proved efficient in monitoring C. notaticeps. About 3494 of C. notaticeps adults were collected during the study. There were no significant differences among traps painted with different colors. The most attractive lure was molasses collecting 75.2% (n = 2627) of the specimens. Although the population peak occurred in December (n = 1162), C. notaticeps were collected throughout the year. The incidence of plants attacked by C. notaticeps ranged from 66.4% (start) to 100% (end).

Automated lesion detectors in retinal fundus images

Diabetic retinopathy (DR) is a sight-threatening condition occurring in persons with diabetes, which causes progressive damage to the retina. The early detection and diagnosis of DR is vital for saving the vision of diabetic persons. The early signs of DR which appear on the surface of the retina are the dark lesions such as microaneurysms (MAs) and hemorrhages (HEMs), and bright lesions (BLs) such as exudates. In this paper, we propose a novel automated system for the detection and diagnosis of these retinal lesions by processing retinal fundus images. We devise appropriate binary classifiers for these three different types of lesions. Some novel contextual/numerical features are derived, for each lesion type, depending on its inherent properties. This is performed by analysing several wavelet bands (resulting from the isotropic undecimated wavelet transform decomposition of the retinal image green channel) and by using an appropriate combination of Hessian multiscale analysis, variational segmentation and cartoon+texture decomposition. The proposed methodology has been validated on several medical datasets, with a total of 45,770 images, using standard performance measures such as sensitivity and specificity. The individual performance, per frame, of the MA detector is 93% sensitivity and 89% specificity, of the HEM detector is 86% sensitivity and 90% specificity, and of the BL detector is 90% sensitivity and 97% specificity. Regarding the collective performance of these binary detectors, as an automated screening system for DR (meaning that a patient is considered to have DR if it is a positive patient for at least one of the detectors) it achieves an average 95-100% of sensitivity and 70% of specificity at a per patient basis. Furthermore, evaluation conducted on publicly available datasets, for comparison with other existing techniques, shows the promising potential of the proposed detectors.

Validation of atmospheric aerosols parallel sampling in a multifold device

In this work, particulate matter was collected using an active sampling system consisting of a PM10 (<10 μm) inlet coupled to a multifold device containing six channels, connected to a vacuum pump. Each channel was equipped with a filter holder fitted with adequately chosen filters. The system was fixed on a metallic structure, which was placed on the roof of the laboratory building, at the Faculty of Sciences, in Lisbon. Sampling took place under flow-controlled conditions. Aerosols were extracted from the filters with water, in defined conditions, and the water-soluble fraction was quantified by ion chromatography (IC) for the determination of inorganic anions (Cl(-), NO3 (-) and SO4 (2-)). Equivalent sampling through the various channels was validated. Validation was based on the metrological compatibility of the content results for the various filters. Ion masses are metrologically equivalent when their absolute difference is smaller than the respective expanded uncertainty. When this condition is verified, the studied multifold device produces equivalent samples.

Chronic stress associated with hypercaloric diet changes the hippocampal BDNF levels in male Wistar rats

Chronic stress, whether associated with obesity or not, leads to different neuroendocrine and psychological changes. Obesity or being overweight has become one of the most serious worldwide public health problems. Additionally, it is related to a substantial increase in daily energy intake, which results in substituting nutritionally adequate meals for snacks. This metabolic disorder can lead to morbidity, mortality, and reduced quality of life. On the other hand, brain-derived neurotrophic factor (BDNF) is widely expressed in all brain regions, particularly in the hypothalamus, where it has important effects on neuroprotection, synaptic plasticity, mammalian food intake-behavior, and energy metabolism. BDNF is involved in many activities modulated by the hypothalamic-pituitary-adrenal (HPA) axis. Therefore, this study aims to evaluate the effect of obesity associated with chronic stress on the BDNF central levels of rats. Obesity was controlled by analyzing the animals' caloric intake and changes in body weight. As a stress parameter, we analyzed the relative adrenal gland weight. We found that exposure to chronic restraint stress during 12 weeks increases the adrenal gland weight, decreases the BDNF levels in the hippocampus and is associated with a decrease in the calorie and sucrose intake, characterizing anhedonia. These effects can be related stress, a phenomenon that induces depression-like behavior. On the other hand, the rats that received the hypercaloric diet had an increase in calorie intake and became obese, which was associated with a decrease in hypothalamus BDNF levels.

The interactions between municipal socioeconomic status and age on hip fracture risk

SUMMARY

Age modifies the effect of area-level socioeconomic status (SES) in the risk of fragility hip fractures (HF). For older individuals, the risk of HF increases as SES increases. For younger individuals, risk of HF increases as SES decreases. Our study may help decision-makers to better direct the implementation of political decisions.

INTRODUCTION

The effect of socioeconomic status (SES) on hip fracture (HF) incidence remains unclear. The objective of this study is to evaluate the association between HF incidence and municipality-level SES as well as interactions between age and SES.

METHODS

From the Portuguese Hospital Discharge Database, we selected hospitalizations (2000-2010) of patients aged 50+, with HF diagnosis (codes 820.x, ICD9-CM), caused by traumas of low/moderate energy, excluding bone cancer cases and readmissions for aftercare. Municipalities were classified according to SES (deprived to affluent) using 2001 Census data. A spatial Bayesian hierarchical regression model (controlling for data heterogeneity and spatial autocorrelation), using the Poisson distribution, was used to quantify the relative risk (RR) of HF, 95% credible interval (95%CrI), and analyze the interaction between age and SES after adjusting for rural conditions.

RESULTS

There were 96,905 HF, 77.3% of which were on women who, on average, were older than men (mean age 81.2±8.5 vs 78.2±10.1 years) at admission (p<0.001). In women, there was a lower risk associated with better SES: RR=0.83 (95%CrI 0.65-1.00) for affluent versus deprived. There was an inverse association between SES and HF incidence rate in the youngest and a direct association in the oldest, for both sexes, but significant only between deprived and affluent in older ages (≥75 years).

CONCLUSIONS

Interaction between SES and age may be due to inequalities in lifestyles, access to health systems, and preventive actions. These results may help decision-makers to better understand the epidemiology of hip fractures and to better direct the available funding.

Sperm Bundles in the Seminal Vesicle of the Crematogaster victima (Smith) Adult Males (Hymenoptera: Formicidae)

This study establishes the presence of spermatodesm in the seminal vesicles of sexually mature males of Crematogaster victima (Smith). In this species, the spermatozoa are maintained together by an extracellular matrix in which the acrosomal regions are embedded. This characteristic has not yet been observed in any other Aculeata. However, the sperm morphology in this species is similar to that described for other ants. The spermatozoa measure on average 100 μm in length, and the number of sperm per bundle is up to 256. They are composed of a head formed by the acrosome and nucleus; this is followed by the flagellum, which is formed by the centriolar adjunct, an axoneme with a 9 + 9 + 2 microtubule pattern, two mitochondrial derivatives, and two accessory bodies. The acrosome is formed by the acrosomal vesicle and perforatorium. The nucleus is filled with compact chromatin with many areas of thick and non-compacted filaments. Both mitochondrial derivatives have the same shape and diameters. The presence of sperm bundles in sexually mature males differentiates C. victima from other ants; however, the similarities in the sperm ultrastructure support the monophyly of this insect group.

Co-encapsulation of resveratrol and curcumin in lipid-core nanocapsules improves their in vitro antioxidant effects

Resveratrol and curcumin are natural antioxidants found in the human diet that have been used in the prevention and treatment of different diseases associated with oxidative stress. Aiming to improve the antioxidant effects of resveratrol and curcumin, lipid-core nanocapsules containing the combination of both polyphenols were developed. Physicochemical characteristics were evaluated and compared to the formulations containing each polyphenol individually. Co-encapsulation did not influence nanotechnological characteristics, and all formulations presented mean diameter around 200 nm, low polydispersity index, and encapsulation efficiency close to 100%. Nanoencapsulation increases the photostability of resveratrol and curcumin, and co-encapsulation improves resveratrol photostability. The in vitro antioxidant activity of polyphenols against HO radicals was enhanced by nanoencapsulation, and a better effect was observed after their co-nanoencapsulation. Also, nanocapsules exhibited controlled release profile, for both polyphenols. The results showed that the strategy to co-encapsulate resveratrol and curcumin is a promising approach to improve the performance of medicines used to prevent and treat diseases associated with oxidative stress.

Genetic diversity and pathogenicity of Metarhizium spp. associated with the white grub Phyllophaga capillata (Blanchard) (Coleoptera: Melolonthidae) in a soybean field

Phyllophaga capillata (Blanchard) was recently described as a soybean pest in Brazil. The occurrence of Metarhizium spp. associated with adults and their pathogenicity were investigated. Natural prevalence of Metarhizium anisopliae was 0.51% in adults collected by light trap. Most Metarhizium isolates were identified as Metarhizium robertsii, although M. anisopliae sensu stricto and a few unidentified isolates were also found. Bioassays with representative isolates selected from different genetic groups resulted in ≤5.6% confirmed mortality against larvae and adults, suggesting low potential of microbial control of this pest by use of indigenous Metarhizium isolates.

Fitness costs associated with low-level dimethoate resistance in Phytoseiulus macropilis

Phytoseiulus macropilis Banks (Acari: Phytoseiidae) is an effective predator of tetranychid mites, but there are no data on its response to pesticides. We investigated the resistance of the predatory mite P. macropilis to the acaricides abamectin and dimethoate, and we examined the fitness costs associated with resistance. Two populations were tested: one from conventional cultivation and another from an area not commercially exploited. After the application of acaricides to the predator, we determined the lethal effects of the acaricides, the instantaneous rate of population increase (r(i)), the predation on Tetranychus urticae Koch (Acari: Tetranychidae) and its ability to locate prey in an olfactometer. P. macropilis exhibited resistance to dimethoate only. The low level of resistance (9.4x) of the predator did not affect their ability to locate prey. However, the dimethoate resistant population was not as effective in contatining prey population when in lower density and exhibited a more pronounced decrease of r(i) in the presence of this acaricide, due to the reduced oviposition of the predator, a likely consequence of the different genetic background of this population.

Cafeteria diet-induced obesity plus chronic stress alter serum leptin levels

Obesity is a disease that has become a serious public health issue worldwide, and chronic stressors, which are a problem for modern society, cause neuroendocrine changes with alterations in food intake. Obesity and chronic stress are associated with the development of cardiovascular diseases and metabolic disorders. In this study, a rat model was used to evaluate the effects of a hypercaloric diet plus chronic restraint stress on the serum leptin and lipids levels and on the weight of specific adipose tissue (mesenteric, MAT; subcutaneous, SAT and visceral, VAT). Wistar rats were divided into the following 4 groups: standard chow (C), hypercaloric diet (HD), stress plus standard chow (S), and stress plus hypercaloric diet (SHD). The animals in the stress groups were subjected to chronic stress (placed inside a 25 cm × 7 cm plastic tube for 1h per day, 5 days per week for 6 weeks). The following parameters were evaluated: the weight of the liver, adrenal glands and specific adipose tissue; the delta weight; the Lee index; and the serum levels of leptin, corticosterone, glucose, total cholesterol, and triglycerides. The hypercaloric diet induced obesity in rats, increasing the Lee index, weight, leptin, triglycerides, and cholesterol levels. The stress decreased weight gain even in animals fed a hypercaloric diet but did not prevent a significant increase in the Lee index. However, an interaction between the independent factors (hypercaloric diet and stress) was observed, which is demonstrated by the increased serum leptin levels in the animals exposed to both protocols.

A methodology to evaluate occupational internal exposure to fluorine-18

The objective of this work is to develop procedures for internal monitoring of (18)F to be applied in cases of possible incorporation of fluoride and (18)FDG, using in vivo and in vitro methods of measurements. The Na I (Tl) 8" x 4" scintillation detector installed at IRD-Whole Body Counter was calibrated for measurements with a whole body anthropomorphic phantom, simulating homogeneous distribution of (18)F in the body. The NaI(Tl) 3"x 3" scintillation detector installed at the IRD-Whole Body Counter was calibrated for in vivo measurements with a brain phantom inserted in an artificial skull, simulating (18)FDG incorporation. The HPGe detection system installed at the IRD-Bioassay Laboratory was calibrated for in vitro measurements of urine samples with 1 liter plastic bottles containing a standard liquid source. A methodology for bioassay data interpretation, based on standard ICRP models edited with the software AIDE-version 6, was established. It is concluded that in vivo measurements have sufficient sensitivity for monitoring (18)F in the forms of fluoride and (18)FDG. The use of both in vitro and in vivo bioassay data can provide useful information for the interpretation of bioassay data in cases of accidental incorporation in order to identify the chemical form of (18)F incorporated.

Abdominal angiostrongyliasis in rodent experimental infection: evidence for systemic circulation of first stage larvae

Eggs of Angiostrongylus costaricensis embrionate and hatch in the course of their migration in the intestinal wall, and first stage larvae (L1) are released in feces. Aiming to investigate the possible systemic circulation of L1, we inoculated mice and, four weeks later, examined their peritoneal cavities and several organs for the presence of L1. A total of 65 larvae were found in extra-intestinal organs (kidney, heart, spleen, liver, lungs). No larvae were found in blood or in the peritoneal cavity. 320 and 578 L1 were found in intestinal wall and intestinal contents, respectively. The experiment was repeated and it confirmed that the metastrongylid larvae found in several organs were larval stages of A. costaricensis. Ten Oligoryzomis sp. rodents, a natural host for A. costaricensis, were also infected and in three animals L1 could be recovered from several organs as well as from bronchoalveolar lavage (BAL) in one of them. These data indicate that systemic circulation and bronchial elimination of L1 may represent an alternative route for release of L1 of A. costaricensis into the environment for transmission to the intermediate host.

Glomus tumour in the digit of a dog

The gross and microscopical features of a glomus tumour in the digit of a 9-year-old dog are described. The tumour consisted of a red nodule near the nail of the third digit of the right forelimb and appeared painful. The tumour cells, which had round to oval hyperchromatic nuclei and scant cytoplasm, were arranged in sheets around blood vessels, or in nests or duct-like structures. This pattern has not been described previously in canine glomus tumours. Mitotic figures were seen only occasionally. Tumour cells were strongly immunolabelled for vimentin and some expressed smooth-muscle actin and desmin. They were negative for cytokeratins, neuron-specific enolase and CD34. Silver impregnation (reticulin method) stained the reticulum around blood vessels, nests of tumour cells and duct-like structures, and a delicate reticulum was seen around each tumour cell. The morphological, immunohistochemical and histochemical patterns helped in the diagnosis of this glomus tumour.

Adolescent pregnancy 1 year later: the effects of abortion vs. motherhood in Northeast Brazil

PURPOSE

To determine social and behavioral consequences of pregnancy and how these differed according to the pregnancy outcome (live birth or abortion) 1 year after the event.

METHODS

This was a prospective study of two groups of young women aged 12-18 years, one attending prenatal services and the other admitted for abortion complications at the same hospital in northeast Brazil. Adolescents who gave birth were subsequently classified as having intended or unintended pregnancies, and those who aborted were divided between those who terminated their pregnancies and those who miscarried. Baseline data were collected between 1995 and 1997 from all teens who met the eligibility criteria. Information was collected through one-on-one interviews using a questionnaire that was structured and precoded. Multiple logistic regression was used to identify characteristics that predicted outcomes at 1 year.

RESULTS

Teens who terminated their pregnancies were the most likely to be in school or working 1 year later. They also showed the greatest increase in self-esteem. The young mothers, however, had the highest self-esteem but perceived the impact of pregnancy on their lives as being more negative than they did initially. Group affiliation was not associated with the quality of partner relationships, which tended to deteriorate over time. The young mothers used contraception at 1 year at higher rates and had experienced fewer subsequent pregnancies than the two abortion groups.

CONCLUSIONS

The experience of adolescent pregnancy for this group of teens produced mixed findings, some more negative than others. Interventions to decrease the adolescent's desire to have a baby will have to be tailored differently from those designed to prevent an unintended pregnancy, but both are needed.

Impact of a 26-month Bacillus sphaericus trial on the preimaginal density of Culex quinquefasciatus in an urban area of Recife, Brazil

A field trial using the entomopathogen Bacillus sphaericus against Culex quinquefasciatus was conducted in a district of Recife, Brazil, an area with a high prevalence of lymphatic filariasis. In this urban area more than 2,500 Cx. quinquefasciatus breeding sites within a 1.2-km2 area were found and subsequently submitted to a long-term treatment with B. sphaericus. To evaluate the impact of treatment on the densities of Cx. quinquefasciatus preimaginal forms, 26 breeding sites, representative of the major site types found in that area, were monitored for 3 years. Parameters such as mean and maximum densities of larval population as well as the frequency of infested sites were recorded before, during, and after the trial. The level of each parameter was greatly reduced during the treatment period, particularly in the 2nd treatment year. A low density of Cx. quinquefasciatus was also maintained throughout the last year, in the absence of treatment. Analysis of the data reported here confirms B. sphaericus as a very effective larvicide against Cx. quinquefasciatus despite the optimal environmental conditions for mosquito proliferation in the urban area of Recife.

Efficacy of Bacillus sphaericus in control of the filariasis vector Culex quinquefasciatus in an urban area of Olinda, Brazil

The efficacy of Bacillus sphaericus 2362 against Culex quinquefasciatus was tested in 1991-94 in a major Brazilian endemic zone for bancroftian filariasis. Continuous selection pressure against the mosquito population was sustained for 18 months through treatment of 2500 potential breeding sites occurring within a 5.7-km2 urban area in the Metropolitan Region of Recife. The impact of this control intervention was evaluated by comparing entomological indices with those from an untreated area. Application of the larvicide kept the Cx. quinquefasciatus population density significantly lower when compared to the untreated area, despite some operational difficulties. Adult densities remained lower for at least 5 months after spraying ceased. Pre-trial microfilaria rates from the untreated and operational area were 13.1% and 7.2%, respectively. A 60% reduction in human exposure to infective bites was recorded as a consequence of this vector population control.

Antifungal activity of volatile constituents of Eugenia dysenterica leaf oil

The essential oil from the hydrodistillation of Eugenia dysenterica leaves consisted mainly of beta-caryophyllene and alpha-humulene as the major sesquiterpene, while limonene and alpha-thujene were the major monoterpene hydrocarbons. The main oxygenated mono and sesquiterpene constituents were alpha-terpineol and beta-caryophyllene oxide, respectively. The oil was investigated against eight strains of Candida albicans, 35 strains of Cryptococcus neoformans var. neoformans, and two C. neoformans var. gattii isolated from HIV-infected individuals with candidosis or cryptococcal meningitis using the agar dilution method. Based on the minimal inhibitory concentration (MIC) values, the most significant results were obtained against Cryptococcus strains. It was observed that 22 strains were inhibited at a concentration of 250 microg/ml, whereas four exhibited potent inhibition with MIC values below 125 microg/ml against 10(6) UFC/ml organisms. We found MICs > or = 3.12 microg/ml for 91.6, 50 and 30% of all Cryptococcus strains in relation of amphotericin B, fluconazole and itraconazole, respectively.

Proteolytic activation of canatoxin, a plant toxic protein, by insect cathepsin-like enzymes

Canatoxin is a protein isolated from jackbean (Canavalia ensiformis), seeds. Injected intraperitoneally, the toxin is lethal to mice but it is inactive if given orally. Canatoxin is also lethal when fed to insects with cathepsin-based digestion while insects with trypsin-based digestion are not affected. The hypothesis that canatoxin is proteolytically activated by cathepsins was investigated. Experiments were performed with 4(th) instar and adult Rhodnius prolixus fed meals containing canatoxin (2.5 microg/mg weight body). While 100% of nymphs died, no effect was observed in adults. Hemolymph taken from nymphs and adults showed the presence of canatoxin's proteolytic fragments. Reduced lethality was seen in R. prolixus 4(th) instars fed meals containing canatoxin and inhibitors of cathepsin enzymes, E-64 (2.0 microM) or Pepstatin-A (2. 0 microM). In another approach, canatoxin was digested in vitro with enzymes from the bruchid, Callosobruchus maculatus, and the resulting peptides were tested in R. prolixus. Three groups of toxic peptides (8,000-12,000 kD range) were separated by gel-filtration. When these peptides were fed to the insects simultaneously with the cathepsin inhibitors, no protective effect was seen. These results confirm the proteolytic activation of canatoxin by insect cathepsin-like enzymes to produce entomotoxic peptide(s). Furthermore, our data point towards overlooked differences in the digestive physiology of distinct life stages of R. prolixus. Arch.

Effects of Pratylenchus brachyurus and P. coffeae on Seedlings of Coffea arabica

Two experiments were carried out to evaluate the effects of Pratylenchus brachyurus and P. coffeae on Coffea arabica. The first experiment was conducted in a greenhouse to determine the effects of Pratylenchus brachyurus and P. coffeae on seedlings of Coffea arabica cv. Mundo Novo. Both Pratylenchus spp. reduced the growth of coffee seedlings. Higher contents of soluble sugars were detected in the leaves of infected plants. The reproduction rate of P. brachyurus was very low on cv. Mundo Novo, indicating an intolerance to this nematode. In a second experiment, C. arabica cultivars Mundo Novo and Catuaf both were intolerant hosts of P. brachyurus.

Management of primary headache in emergency services of Santos and surrounding towns

OBJECTIVES

Primary headaches are often seen by Clinicians on duty at Emergency Services. We have investigated the treatment of such patients by 43 medical doctors who have been working at Emergency Services in the city of Santos and surrounding towns for many years.

RESULTS

We confirmed the high prevalence of primary headaches in Emergency Services. There seem to be diagnosis difficulties concerning differentiating attacks of migraine and tension type headache. We also observed that IV dipirone was the most frequently prescribed treatment for patients with primary headaches in this study. There is no protocol in the literature which recommends IV dipirone for the treatment of migraine attacks or other primary headaches.

CONCLUSION

It would be advisable to perform controlled double blind studies in order to verify the advantages of IV dipirone in the treatment of intense attacks primary headaches. We concluded that headache management recycling programs could be of interest for doctors who regularly work at Emergency Services.

Effect of different experimental parameters on the potentiometric evaluation of blood electrolytes using K+ as a test cation

Potentiometric evaluation of ionic concentrations in physiological media has been reported to be significantly affected by the albumin containing matrix. Previous studies have attempted to clarify the origin of different patterns of variation of E versus albumin concentration at a constant 0.01 mol dm-3 KCl, depending on the experimental methodologies. This paper reports on measurements of K+ in albumin (BSA) containing KCl solutions, which have been pursued following different methodologies concerning the sequence of measurements, i.e., starting either from the most concentrated solution (100 g dm-3) (A) or from the most dilute solution (20 g dm-3) (B), and solution preparation, (a) dilution of an initial 100 g dm-3 albumin solution by successive addition of 0.01 mol dm-3 KCl, (b) concentration of an initial 20 g dm-3 albumin solution by addition of solid substance, (c) independent preparation of each albumin solution (20, 40, 60, 80 and 100 g dm-3) or (d) preparation of each albumin solution from direct dilution of a 100 g dm-3 stock solution with 0.01 mol dm-3 KCl. Convenient calculations were made and showed a significant contribution of albumin to the liquid-liquid junction potential. The variation of potential with albumin concentration is smaller for hypertonic than for isotonic bridge solutions, both for the dilution series (A,a and A,d) and for the concentration series (B,c and B,d). When the method for increasing the concentration is performed by addition of a solid substance to an initially diluted albumin (B,b), the slope of the E versus albumin concentration plot is larger for hypertonic than for isotonic reference electrolytes. This latter finding is in agreement with Payne's results when ultrafiltration was used to concentrate a protein solution. These observations are a clear indication that the method of preparation of concentrated protein solutions may significantly affect the results.

Prophylactic and persistent efficacy of doramectin against Cochliomyia hominivorax in cattle

Two prophylactic studies and one persistent efficacy study were conducted in Brazil to evaluate one injection of doramectin at a dose rate of 200 micrograms kg-1 against induced infestations of the New World screwworm, Cochliomyia hominivorax. In each prophylactic study, 12 calves were allocated to two groups of six animals. Six calves were treated with doramectin and six with saline. Two hours after treatment, animals were anesthetized and received two incisions, one in the shoulder and one in the rump. Each incision was then infested with 50 first instar larvae. In the persistent efficacy study, 24 calves were allocated to six groups (T1-T6) of four animals each. On the day of treatment, three groups (T1, T3 and T5) were treated with saline and three groups (T2, T4 and T6) with doramectin. All animals were anesthetized and received four incisions, one in the shoulder and one in the rump of each side. Each incision was then infested with 30 first instar larvae of C. hominivorax with the following schedule: T1 and T2 at Day 3, T3 and T4 at Day 7, and T5 and T6 at Day 14 post-treatment. Calves were observed daily and incisions evaluated for 8 days post-infection. Larvae that completed development and exited the wounds were collected and incubated to evaluate viability. In all experiments, doramectin was 100% efficacious in preventing screwworm infestation caused by field isolates of C. hominivorax. First instar larvae were eliminated from the incisions of doramectin-treated calves between 24 and 48 h post-treatment, and no third instar were recovered at any time. As a consequence, healing started at 24 h and was completed at 96-120 h post-infection. Screwworm infestations and viable third-instar larvae developed in all the incisions in non-treated calves, and healing did not begin until larvae had completed their normal life cycle and exited the wounds. The persistent efficacy of a single injection of doramectin extended beyond 14 days.

Expression of blood clotting factor VIII:C gene in capillary endothelial cells

The essential role of Factor VIII:C (FVIII:C, anti-hemophilia factor A) as a cofactor for Factor IXa-dependent activation of Factor X has been established. In this paper, we describe that capillary endothelial cells from bovine adrenal medulla express active FVIII:C gene. Accumulation of FVIII:C in conditioned media from an 8-day-old culture is approximately twice as high as that stored in the cell when immunoprecipitated FVIII:C was analyzed for its ability to convert Factor X to Factor Xa. Analysis of [35S]methionine-labeled and immunoprecipitated FVIII:C from cells or conditioned media on SDS-PAGE under fully denatured conditions indicated that the newly synthesized FVIII:C consists of heavy chain of M(r) 200,000 and light chain of M(r) 46,000. The secreted FVIII:C in the non-reduced condition however, has a molecular weight of 270,000 which suggests that in native protein, the heavy and light chains are held together by S-S bonds. Furthermore, susceptibility of the immunoprecipitated FVIII:C to N-glycanase digestion establishes that the endothelial cells derived FVIII:C contains asparagine-linked carbohydrate side chains.

Role of extracellular signaling on endothelial cell proliferation and protein N-glycosylation

In vitro studies of angiogenic phenomenon have been limited due to nonavailability of a simple and biologically relevant model of the capillary wall. Recent development of a capillary endothelial cell line from the vascular bed of bovine adrenal medulla made us to study the effect of heparin, thrombin, thyroxine, glucagon, insulin, and phorbol myristate acetate (PMA) on the proliferative and metabolic activities such as glycosylation of asparagine-linked glycoproteins of these cells in culture. Out of six different agents studied here, only heparin, thrombin, and thyroxine reduced the doubling time of these cells by 24 hr with no observed morphological abnormality. Glucagon, showed marginal reduction in the cell doubling time. By contrast, insulin and PMA enhanced the doubling time. Insulin treatment though induced the S phase of cell cycle but it blocked the cells entry into the G2 + M phase. PMA arrested the cells in G0/G1 phase. The cellular response to protein N-glycosylation is increased in the presence of thyroxine, insulin, and thrombin and the effect is dose dependent. Further analysis on SDS-PAGE indicated that glycosylation of 80-120 kDa and 43 kDa glycoprotein species are enhanced when these cells are treated with insulin and thrombin. Glycopeptide generated from these glycoproteins suggested that they all carry "high mannose" and "complex" type oligosaccharide chains attached to their protein core.

Evaluation of the El Kholy technique for grouping beta-hemolytic streptococci

One hundred and eleven strains of beta-hemolytic streptococci of human origin were grouped by the new nitrous acid procedure described by El Kholy et al. The results were comparable to the grouping obtained by the classical Lancefield hot-hydrochloric acid method. The El Kholy technique is simple and economic and is shown to be as sensitive and specific as the Lancefield procedure. We recommend the new method for routine use in the clinical laboratory and in studies on the prevalence of Streptococcus pyogenes in a developing country such as Brazil.