The Dedalo Project, a Community-based Prevention Program for the Promotion of Healthy Behaviors in Adult Population: Model Description and Target Population Assessment

Noncommunicable diseases (NCDs) are the leading global cause of death. The Italian National Prevention Plan (INPP) highlights the importance of health promotion and NCD prevention while avoiding health inequalities. In line with the INPP guidelines, we initiated a multicomponent community-based intervention program, named the Dedalo project, to promote healthy and active aging among population living around the Vercelli’s municipality, Italy. A cross-sectional analysis, that used the baseline data of a longitudinal study of the project, evaluated the program’s ability to enroll participants participants who represent the socioeconomic conditions present in the municipality. To this end, we compared the main social characteristics and behaviors of 40–74-year-old subjects (n = 155), who had attended at least one Dedalo activity, to those of same age individuals (n = 124) randomly extracted from the general population. We found that most participants were women (81.3%) and had a higher SES compared to the general population. Furthermore, they were healthier—OR 0.52, 95% CI 0.31–0.87 for self-reported diseases—and displayed healthier behaviors—OR 0.20, 95% CI 0.08–0.46 for smokers; 0.32 95%, CI 0.16–0.64 for fruit/vegetable consumers; and 0.36 95% CI 0.20–0.64 for sweet beverages consumers. Overall, our initial evaluation indicates that the Dedalo project has so far struggled to enroll individuals with low SES, men with any SES, and subjects displaying unhealthy behaviors, thereby failing to meet the INPP goal of preventing NCDs while avoiding health disparities. Thus, efforts should be made to ensure that this community-based intervention program can effectively reach all the target population, in particular those individuals most exposed to behavioral risk factors.

Time and classical equations of motion from quantum entanglement via the Page and Wootters mechanism with generalized coherent states

We draw a picture of physical systems that allows us to recognize what “time” is by requiring consistency with the way that time enters the fundamental laws of Physics. Elements of the picture are two non-interacting and yet entangled quantum systems, one of which acting as a clock. The setting is based on the Page and Wootters mechanism, with tools from large-N quantum approaches. Starting from an overall quantum description, we first take the classical limit of the clock only, and then of the clock and the evolving system altogether; we thus derive the Schrödinger equation in the first case, and the Hamilton equations of motion in the second. This work shows that there is not a “quantum time”, possibly opposed to a “classical” one; there is only one time, and it is a manifestation of entanglement.

Discussions about the role of time in quantum mechanics are often detached from the corresponding classical limit. Here, the authors provide the Page and Wootters mechanism with a classical limit using the large-N approach based on generalized coherent states, without the need to introduce time measurements.

Psychosocial empowerment-based interventions for smoking reduction: concepts, measures and outcomes. A systematic review

Although empowerment is a widely used concept in health-related areas, its definition remains unclear. While there is evidence for the effectiveness of empowerment interventions in improving some psychosocial factors linked to health (e.g. patient self-care strategy, coping skills, access and effective use of health services) and some health outcomes like mental health and HIV/AIDS-related behaviour, other data appear to contradict this. Moreover, concepts, measures, and outcomes related to empowerment are operationalized in different ways. Using the case of tobacco control programmes, we wanted to explore: (a) how research on smoking reduction/prevention has conceptualized empowerment; (b) which measures and instruments have been used to assess behaviour outcomes and the empowerment process. We hypothesized that the transformative potential that characterizes empowerment is marginally considered.A total of 18 studies reporting on the effect of prevention interventions on smoking and/or empowerment outcomes were reviewed. Two kinds of study were distinguished: (a) studies reporting behaviour outcomes without data about the impact on empowerment; (b) studies analysing the empowerment process. Among this latter type, some studies did not provide information about the specific behaviour (smoking), while others examined the impact of intervention on both smoking and empowerment. In about half of all studies, empowerment strategies were found to be effective in improving smoking outcomes, while no differences were found between intervention and control groups in the remaining studies. The present review suggests that pragmatic definitions of empowerment need to be developed in order to promote its transferability and evaluation.

[Socioeconomic and regional inequalities in smoking cessation in Italy, 2014-2017]

OBJECTIVES

to study regional differences in Italy of quit smoking attempts and of successful abstinence, in relation to socioeconomic status, cigarettes per day (cig/die), and smoking cessation method in a representative sample of the population resident in Italy.

DESIGN

cross-sectional survey.

SETTING AND PARTICIPANTS

in 2014-2017, PASSI survey (the ongoing Italian behavioural risk factor surveillancesystem) gathered data on smoking and sociodemographic characteristics of 35,157 smokers; 13,130 aged 18-69 years made >1 quit attempt in the previous year, 1,176 of them were successful quitters for >6 months.

MAIN OUTCOME MEASURES

proportion of smokers who tried to quit; proportion of smokers who successfully quitted.

RESULTS

about 35% of smokers made >1 quit attempt in the last year. Northern Italians and smokers with many economic difficulties were more likely to make a quit attempt, whereas heavy smokers were less likely. About 10% of attempters were abstinent for >6 months: from 6% in Campania and Abruzzo to 17% in the Bolzano province. Attempters who smoked <20 cig/die had higher likelihood to be abstinent, compared to those smoking <20 cig/die. Attempters with many economic difficulties had the lowest likelihood to be abstinent (7%), with no differences by region, educational level, quitting method. Attempters with no economic difficulties recorded the highest cessation rates (12%). Among them, those from Northern Italy, Tuscany, Marche, and Lazio (Central Italy), and Apulia (Southern Italy) compared to attempters from most Southern regions, and those with high education level or using traditional quitting methods compared to those using electronic cigarettes or unaided were more likely to be abstinent for >6 months.

CONCLUSIONS

smokers with many economic difficulties in all Italy, and those with no economic difficulties residing in Umbria and in most Southern Italian regions, except for Basilicata and Puglia, recorded lower chances to quit. Regional differences may have two possible explanations integrating each other: Northern-Central regions are in a slightly more advanced stage in the tobacco epidemic; regions which developed specific tobacco control interventions in their Prevention Plans recorded higher quitting rates. Not-yet-implemented interventions could promote smoking cessation in smokers from Southern Italy and in those with lower socioeconomic status: reimbursement of smoking cessation treatments, a well-developed national Quitline linked to a webplatform and to mobile phone application or text-messaging, an opt-out smoking cessation service offered systematically to all smokers at every encounter in hospitals or health services.

A School-Based Program to Promote Well-Being in Preadolescents: Results From a Cluster Quasi-Experimental Controlled Study

Diario della Salute [My Health Diary] is a school-based program designed to enhance the subjective well-being and health of 12- to 13-year-old students. We hypothesized that providing students with the social and emotional skills to fulfill their potential and deal with common developmental tasks of adolescence (e.g., onset of puberty, identity development, increased responsibilities and academic demands) would result in improved well-being and health. The program comprises five standardized interactive lessons concerning common psychosocial and health issues in adolescence, and two narrative booklets addressed to both students and their parents. We evaluated the effectiveness of the program in terms of the students’ subjective well-being, aggressive behavior, and health behavior. Using a quasi-experimental study design, schools in the intervention group implemented the full program and those in the comparison group received their regular curriculum. We administered measures of the study’s objectives both before and after program implementation. Statistical analyses accounted for within-school clustering, potential socioeconomic and demographic confounding, and pre-implementation levels of these measures. We sampled 62 schools and allocated 2630 students to either an intervention or comparison group. Sociodemographic characteristics and baseline outcomes were balanced across study groups. Unexpectedly, respondents in the intervention group had 0.38 greater mean adjusted score of the WHO/Europe Health Behaviour in School-Aged Children Symptom Checklist instrument than respondents in the comparison group, indicating a reduction in subjective well-being. We did not observe any program effects on aggressive and health behaviors. The apparent reduction in subjective well-being reflected by an increased perception of psychosomatic complaints is suggestive of either increased emotional competence or, potentially, iatrogenic program effects. While greater emotional competence is positively associated with well-being over the course of life, the program in its present form should not be disseminated due to the possibility of adverse unintended effects.

Quit attempts and smoking cessation in Italian adults (25-64 years): factors associated with attempts and successes

Background

Over the past 50 years there was a substantial decrease in the prevalence of smoking in Italy. The objective of this work is to describe attempts to quit and cessation success in Italian smokers.

Methods

A surveillance on health-related behaviors (PASSI) was conducted in 2007-13 on a sample of 203 610 Italian adults 25-64 years of age. An analysis of smokers' characteristics and behaviors was performed, focusing on attempts to quit and quit success. Data from national surveys (ISTAT) from 1983 to 2013 (Italian adults, 25-64 years of age, 1983: 46 634; 1987: 40 915; 1990: 36 622; 2000: 77 531; 2005: 71 032; 2013: 64 205) were used to explore if a cessation trend in Italy exists.

Results

Smokers who quit in the previous year and were still abstinent when interviewed increased from 1990 to 2013. In the years 2011-13, 38% of people who had smoked in the last 12 months reported at least a quit attempt during the same period and 7% were still abstinent when interviewed. An association of successful recent quit attempts with higher educational level, absence of economic difficulties and younger age was found. In the years 2007-13, the great majority tried to stop unaided. Having received assistance from a cessation program did not increase the probability of enduring abstinence.

Conclusions

In Italy interventions to drive more smokers to quit should be focused in particular on disadvantaged groups. Initiatives have to be studied not only to incentive more smokers to try to quit, but also to maintain abstinence over time.

[Efficacy and effectiveness of prevention programs in the population: for a more rational choice of public health interventions.]

INTRODUCTION

Evidence Based Prevention is becoming increasingly important to guide the policy-makers to choose preventive interventions to be offered to the population. Sometimes however the impact of an intervention in real conditions (effectiveness) may be smaller than the efficacy estimated in studies conducted in experimental settings. This can be due for example to suboptimal coverage of the intervention or to poor compliance of the involved subjects. Regrettably, this aspect is rarely taken into account in the planning of preventive interventions. To evaluate the discrepancy between efficacy and effectiveness of prevention programs we used as examples two interventions for smoking cessation currently available in Italy: 1) Interventions offered by Smoking Cessation Centers; 2) "Minimal Advice" provided by family doctors.

METHODS

Using epidemiological data we estimated the expected effectiveness of interventions under different scenarios.

RESULTS

Even assuming that Smoking Cessation Centers always offer the best available intervention (efficacy: 82%), they do not seem able to have a major effect on smoking cessation in the population (effectiveness: 0.8%). This is due to the very small number of smokers that seek help to these centers (1%). On the contrary, interventions based on minimal advice are anticipated to have much higher effectiveness (21%).

CONCLUSION

Evidence of efficacy of an intervention is not sufficient to ensure that this will have a significant impact on health. The decision to implement a preventive action should be preceded by a careful evaluation of the expected effectiveness and be followed by a post-implementation monitoring to estimate the real impact of the intervention.

[Interventions for healthy diet promotion in Italy]

OBJECTIVES

to describe the prevention interventions conducted by the Regional health services to promote a healthy diet.

MATERIAL AND METHODS

the database ProSA, which contains prevention interventions conducted by some Italian regions, has been analysed. Programmes identified as «Diet - physical activity» were selected, and the ones that had the promotion of healthy diet in unselected populations as objective were included. Then, the programmes were analysed and described.

RESULTS

a total of 87 programmes were included, 23 of which are certainly conducted during 2013-14. 91% are school-based, particularly targeted to middle schools, and 37% are based on classroom lessons. No programme made any reference to specific evidence, while 11% of them cited scientific generic but relevant papers. 15% of the programmes described some evaluation process, but only 1% has proposed a study design with controls. Limiting the analysis to the region that contributed with the largest amount of recorded programmes, it can be estimated that programmes does not reached more than 0.03% of the general population, and 4% of the school population.

CONCLUSIONS

in Italy, there is not a survey system to collect preventive interventions conducted by regional health authorities. The analysis of ProSA, an experimental system, allows us to highlight that the promotion of a healthy diet is based on interventions targeting only the school population and referring to scientific evidence in a very limited way. Moreover, they seem to cover very small part of the target population.

Multimodal neurological approach can lead the treatment in postcardiac arrest persistent refractory status epilepticus

Refractory status epilepticus (RSE) is a common challenge in the setting of post resuscitation care. We describe how multimodal neurological approach can lead treatment and improve the prognosis. We report on three survivors of cardiac arrest (CA) who had good neurological outcomes after mild hypothermia (TH), despite exhibiting persisting RSE requiring treatment with several antiepileptic (AED) and anesthetic drugs, including barbiturate-induced coma. No evidence-based data exist to guide management of RSE in the setting of anoxic brain injury. Our cases emphasize the need for continuous active treatment led by a multimodal approach in order to improve neurological outcome.

School policies for preventing smoking among young people

BACKGROUND

School tobacco policies (STPs) might prove to be a promising strategy to prevent smoking initiation among adolescents, as there is evidence that the school environment can influence young people to smoke. STPs are cheap, relatively easy to implement and have a wide reach, but it is not clear whether this approach is effective in preventing smoking uptake.

OBJECTIVES

To assess the effectiveness of policies aiming to prevent smoking initiation among students by regulating smoking in schools.

SEARCH METHODS

We searched seven electronic bibliographic databases, including the Cochrane Tobacco Addiction Group specialized register, MEDLINE, EMBASE, PsycINFO and ERIC. We also searched the grey literature and ongoing trials resources. The most recent search was performed in May 2014.

SELECTION CRITERIA

We included cluster-randomised controlled trials (c-RCTs) in which primary and secondary schools were randomised to receive different levels of smoking policy or no intervention. Non-randomised controlled trials, interrupted time series and controlled before-after studies would also have been eligible. Cross-sectional studies were not formally included but we describe their findings and use them to generate hypotheses to inform future research.

DATA COLLECTION AND ANALYSIS

We independently assessed studies for inclusion in the review, and present a narrative synthesis, as the studies are too limited in quality to undertake a formal meta-analysis.

MAIN RESULTS

We found only one study which was eligible for inclusion in the review. It was judged to be at high risk of bias. The study compared two 'middle schools' from two different regions in China. The experimental conditions included the introduction of a tobacco policy, environmental changes, and communication activities, while the control condition was no intervention. After a year's follow-up the study found no differences in smoking prevalence between intervention and control schools. We also described 24 observational studies, the results of which we considered for hypothesis generation. In these, policy exposure was mainly described using face-to-face interviews with school staff members, and the outcome evaluation was performed using self-administered questionnaires. Most studies reported no differences in students' smoking prevalence between schools with formal STPs when compared with schools without policies. In the majority of studies in schools with highly enforced policies, smoking bans extended to outdoor spaces, involving teachers and including sanctions for transgressions, with assistance to quit for smokers plus support by prevention programmes, there was no significant difference in smoking prevalence when compared to schools adopting weaker or no policies.

AUTHORS' CONCLUSIONS

Despite a comprehensive literature search, and rigorous evaluation of studies, we found no evidence to support STPs. The absence of reliable evidence for the effectiveness of STPs is a concern in public health. We need well-designed randomised controlled trials or quasi-experimental studies to evaluate the effectiveness of school tobacco policies.

Public beliefs and attitudes towards depression in Italy: a national survey

BACKGROUND

Previous studies have shown that attitudes towards depression may be influenced by country-specific social and cultural factors. A survey was carried out to collect beliefs on and attitudes toward depression in Italy, which has an established community-based mental health system.

METHODS

A telephone survey was carried out in a probabilistic sample aged ≥15 years. A 20-item questionnaire was administered to explore knowledge of depression, stigma, causal beliefs, treatment preference, and help-seeking attitudes.

RESULTS

Of the 1001 participants, 98% were aware of depression, and 62% had experienced it, either directly or indirectly. A widespread belief (75%) was that people suffering from depression should avoid talking about their problem. A minority of the sample viewed depression as a condition that should be managed without recourse to external help or a "socially dangerous" illness. Among perceived causes of depression, most respondents mentioned life stressors or physical strains. Psychologists were often indicated as an adequate source of professional help. Half of the sample believed that depression should be pharmacologically treated, but drugs were often seen as addictive. Referring to a primary care physician (PCP) was considered embarrassing; furthermore, many people thought that PCPs are too busy to treat patients suffering from depression.

CONCLUSIONS

Our findings indicate that depression is seen as a reaction to significant life events that should be overcome with the support of significant others or the help of health professionals (mainly psychologists). However, there are still barriers to the disclosure of depressive symptoms to PCPs, and concerns about the addictive effect of antidepressants. In the presence of a gap between people's beliefs and what health professionals consider appropriate for the treatment of depression, a "shared decision making" approach to treatment selection should be adopted taking into account the patients' preference for psychological interventions to ensure active compliance with effective treatments.

[Community interventions among tobacco control strategies: coping with their definition and evaluation]

Community interventions represent a key component of the current anti-smoking strategies. We propose a conceptual framework for classifying these interventions, based on the concept of community utilised in different studies. We identified 5 different focuses: geographical areas (i.e. city, county, region); targets (sub-group of a population); settings (school, workplace); culture and individual attitudes; multilevel networks. These two latter views refer to functional rather than to structural aspects of a community and they represent the most promising approaches to design intervention strategies. Communities are represented as a group of organizations, systems and social networks investigating individual, environmental and cultural factors that can strongly influence behavioural changes. The great heterogeneity in what the authors mean as community interventions has in our opinion affected the evaluation of their impact. To facilitate their evaluation and to contribute to the detection of determinants, as well as of barriers, it is necessary to compare community interventions sharing similar theoretical approaches and focuses. Also, studies aimed at assessing the steps of the implementation process of community programmes may allow to identify those components related to specific levels of intervention, thus enabling the generalisation of results. To reach this goal it may be helpful to combine study designs allowing for both quantitative and qualitative assessments, such as action research and participatory evaluation research.

[Effective laws for tobacco control: EU directives and Italian legislation]

Effective tobacco control policies include law issuing: bans/restrictions on smoking in public areas and workplaces, increasing of taxes on tobacco products, bans on advertising of tobacco products, warning labels on cigarette boxes. For some of these policies the European Union (EU) has introduced specific directives that EU member states have to put into law. This paper briefly presents literature data, EU directives and the laws consequently issued in Italy. The importance of standardizing European legislation, especially for those policies that are not enforced by EU directives is also discussed. In Italy and in some other European countries smoking is forbidden in public and work-places, despite no EU directive. The positive impact of this ban in these countries suggests that it should be considered a priority in the European policies against tobacco in order to reduce the gap between literature recommendations and actions.

Intraoperative monitoring of myocardial ischemia

Cardiovascular complications are commonly observed in surgical patients, and myocardial ischemia is the most important determinant of perioperative morbidity. The clinical criteria defining a patient population at increased risk for cardiovascular events are presented. The authors review the principles of monitoring and diagnosing myocardial ischemia, focusing on eletrocardiography and TransEsophageal Echocardiography. These patients must be closely followed long after the end of surgery, since the risk for cardiac morbidity is high for several hours postoperatively.

[Effectiveness and side effects of the treatment with propafenone and flecainide for recent-onset atrial fibrillation]

BACKGROUND

The authors report their experience in recent-onset atrial fibrillation treated with intravenous flecainide and propafenone, in comparison with the placebo group.

METHODS

We randomized 352 (138 in the flecainide group, 164 in the propafenone group and 50 in the control group) consecutive patients (167 males, 185 females, mean age 59 +/- 12 years) with recent-onset atrial fibrillation. The electrocardiogram of all patients was monitored for at least 24 hours.

RESULTS

The restoration of sinus rhythm occurred in 72.5, 80.4, 86.2 and 89.8% of patients in the flecainide group; in 54.3, 68.3, 75 and 92.1% in the propafenone group; in 22.2, 27.8, 35.2 and 46.3% in the control group, at 1, 3, 6 and 24 hours respectively. The occurrence of side effects was the same in all treatment groups, and occurred in about 10% of patients in the flecainide and propafenone groups, and in 4% in the control group. In our study population the treatment of recent-onset atrial fibrillation with flecainide was faster in converting the arrhythmia to sinus rhythm (p < 0.005 at 1 hour, p < 0.05 at 3 hours, p = 0.05 at 6 hours). However within 24 hours the efficacy of either flecainide or propafenone was the same (p = NS at 24 hours).

CONCLUSIONS

Side effects were similar in both treatment groups. In particular malignant arrhythmias did not occur in the treatment groups and in the control group.

Vibrio cholerae in the horn of Africa: epidemiology, plasmids, tetracycline resistance gene amplification, and comparison between O1 and non-O1 strains

The prevalence of Vibrio cholerae O1 and non-O1 has been investigated in numerous Somali regions of the Horn of Africa from 1983 to 1990. From January 1983 to January 1985 and between December 1986 and December 1990, no strains of V. cholerae O1 and 226 strains (5.3%) of V. cholerae non-O1 were isolated from 4,295 diarrhea cases. During a cholera epidemic in 1985 and 1986, the overall case-fatality rate was 13% and the attack rate was 3-3.5 per 1,000 population. Matched case-control studies identified a waterborne route of transmission. A drug-susceptible Ogawa strain from Ethiopia caused the introduction of the disease into northern Somalia. There were two major resistant derivatives of the original strain, and the one resistant to ampicillin, kanamycin, streptomycin, sulfonamide, and tetracycline (TC) predominated in the spreading disease. In 1986, susceptible Ogawa strains quickly displaced this resistant strain. The two incompatibility group C plasmids responsible for the resistance patterns had complex and scattered differences in their structures. Physical analysis of the plasmid DNA region coding for TC resistance demonstrated its genetic amplification in highly resistant variants of Ogawa strains.

H-NS regulation of virulence gene expression in enteroinvasive Escherichia coli harboring the virulence plasmid integrated into the host chromosome

We have previously shown that integration of the virulence plasmid pINV into the chromosome of enteroinvasive Escherichia coli and of Shigella flexneri makes these strains noninvasive (C. Zagaglia, M. Casalino, B. Colonna, C. Conti, A. Calconi, and M. Nicoletti, Infect. Immun. 59:792-799, 1991). In this work, we have studied the transcription of the virulence regulatory genes virB, virF, and hns (virR) in wild-type enteroinvasive E. coli HN280 and in its pINV-integrated derivative HN280/32. While transcription of virF and of hns is not affected by pINV integration, transcription of virB is severely reduced even if integration does not occur within the virB locus. This indicates that VirF cannot activate virB transcription when pINV is integrated, and this lack of expression accounts for the noninvasive phenotype of HN280/32. Virulence gene expression in strains HN280 and HN280/32, as well as in derivatives harboring a mxiC::lacZ operon fusion either on the autonomously replicating pINV or on the integrated pINV, was studied. The effect of the introduction of plasmids carrying virB (pBNI) or virF (pHW745 and pMYSH6504), and of a delta hns deletion, in the different strains was evaluated by measuring beta-galactosidase activity, virB transcription, and virB-regulated virulence phenotypes like synthesis of Ipa proteins, contact-mediated hemolysis, and capacity to invade HeLa cells. The introduction of pBN1 or of the delta hns deletion in pINV-integrated strains induces temperature-regulated expression or temperature-independent expression, respectively, of beta-galactosidase activity and of all virulence phenotypes, while an increase in virF gene dosage does not, in spite of a high-level induction of virB transcription. Moreover, a wild-type hns gene placed in trans fully reversed the induction of beta-galactosidase activity due to the delta hns deletion. These results indicate that virB transcription is negatively regulated by H-NS both at 30 and at 37 degrees C in pINV-integrated strains and that there is also a dose-dependent effect of VirF on virB transcription. The negative effect of H-NS on virB transcription at the permissive temperature of 37 degrees C could be due to changes in the DNA topology occurring upon pINV integration that favor more stable binding of H-NS to the virB promoter DNA region. At 30 degrees C, the introduction of the high-copy-number plasmid pMYSH6504 (but not of the low-copy-number pHW745) or of the deltahns deletion induces, in strains harboring an autonomously replicating pINV, beta-galactosidase activity, virB transcription, and expression of the virulence phenotypes, indicating that, as for HN280/32, the increase in virF gene dosage overcomes the negative regulatory effect of H-NS on virB transcription. Moreover, we have found that virF transcription is finely modulated by temperature and, with E. coli K-12 strains containing a virF-lacZ gene fusion, by H-NS. This leads us to speculate that, in enteroinvasive bacteria, the level of Virf inside the cell controls the temperature-regulated expression of invasion genes.

A two-year study of enteric infections associated with diarrhoeal diseases in children in urban Somalia

A hospital-based systematic sample of 1667 children with severe diarrhoeal disease was studied in Mogadishu, Somalia, throughout 1983 and 1984. One or more enteric pathogens were found in 61% of the patients. Rotavirus (25%), enterotoxigenic Escherichia coli (11%), Shigella spp. (9%), Aeromonas hydrophila (9%), Giardia lamblia trophozoites (8%), Campylobacter jejuni (8%), and Vibrio cholerae non-O1 (6%) were the most frequently identified pathogens. Age-specific detection rates of enteric pathogens and helminths, seasonal patterns, and relationship of some specific infections with feeding status and main clinical features have been defined for all the sample examined.

Comparative mutational analysis of wild-type and stretched tRNA3(Leu) gene promoters

We demonstrate that, when the yeast tRNA(3Leu) gene is stretched so that the distance between the two portions of the intragenic promoter is increased to 365 base pairs, the A and B blocks remain functional. Mutations in the A block, which show a weak phenotype when inserted in the wild type, exert a dramatic effect when inserted into the stretched gene. Experiments with extensively purified transcription factor tau indicate that the tau B-B block interaction is not influenced by A-B distance; only the ability of tau A to interact with A block sequences is affected, possibly because of the additional free-energy cost of forming a large loop of the intervening DNA.