A spatial approach for the epidemiology of antibiotic use and resistance in community-based studies: the emergence of urban clusters of Escherichia coli quinolone resistance in Sao Paulo, Brasil

Background: Population antimicrobial use may influence resistance emergence. Resistance is an ecological phenomenon due to potential transmissibility. We investigated spatial and temporal patterns of ciprofloxacin (CIP) population consumption related to E. coli resistance emergence and dissemination in a major Brazilian city. A total of 4,372 urinary tract infection E. coli cases, with 723 CIP resistant, were identified in 2002 from two outpatient centres. Cases were address geocoded in a digital map. Raw CIP consumption data was transformed into usage density in DDDs by CIP selling points influence zones determination. A stochastic model coupled with a Geographical Information System was applied for relating resistance and usage density and for detecting city areas of high/low resistance risk. Results: E. coli CIP resistant cluster emergence was detected and significantly related to usage density at a level of 5 to 9 CIP DDDs. There were clustered hot-spots and a significant global spatial variation in the residual resistance risk after allowing for usage density. Conclusions: There were clustered hot-spots and a significant global spatial variation in the residual resistance risk after allowing for usage density. The usage density of 5-9 CIP DDDs per 1,000 inhabitants within the same influence zone was the resistance triggering level. This level led to E. coli resistance clustering, proving that individual resistance emergence and dissemination was affected by antimicrobial population consumption.

Compatibility of Neoseiulus paspalivorus and Proctolaelaps bickleyi, candidate biocontrol agents of the coconut mite Aceria guerreronis: spatial niche use and intraguild predation

The eriophyid mite Aceria guerreronis occurs in most coconut growing regions of the world and causes enormous damage to coconut fruits. The concealed environment of the fruit perianth under which the mite resides renders its control extremely difficult. Recent studies suggest that biological control could mitigate the problems caused by this pest. Neoseiulus paspalivorus and Proctolaelaps bickleyi are two of the most frequently found predatory mites associated with A. guerreronis on coconut fruits. Regarding biological control, the former has an advantage in invading the tight areas under the coconut fruit perianth while the latter is more voracious on the pest mites and has a higher reproductive capacity. Based on the idea of the combined use/release of both predators on coconut fruits, we studied their compatibility in spatial niche use and intraguild predation (IGP). Spatial niche use on coconut fruits was examined on artificial arenas mimicking the area under the coconut fruit perianth and the open fruit surface. Both N. paspalivorus and P. bickleyi preferentially resided and oviposited inside the tight artificial chamber. Oviposition rate of P. bickleyi and residence time of N. paspalivorus inside the chamber were reduced in the presence of a conspecific female. Residence of N. paspalivorus inside the chamber was also influenced by the presence of P. bickleyi. Both N. paspalivorus and P. bickleyi preyed upon each other with relatively moderate IGP rates of adult females on larvae but neither species yielded nutritional benefits from IGP in terms of adult survival and oviposition. We discuss the relevance of our findings for a hypothetic combined use of both predators in biological control of A. guerreronis.

Water use and crop coefficient for hybrid DKB 390

Water use and crop coefficient for hybrid DKB 390. This work aims to characterize the water use of maize hybrid DKB 390 under suitable conditions of irrigation for both sufficient and below-optimal situations of nitrogen supply. Crop coefficient values for different stages are also presented as a result, in order to provide the basis for crop water budget and management throughout the cycle. A field experiment was carried Out during the main season, in which biomass, soil moisture, leaf area, climate data and light transmittance were evaluated. These have allowed deriving water balance, use and efficiency. The mentioned genotype requires around 600 nun for high yield targets, being less efficient when led under below-optimal nitrogen fertilization.

Review of diagnostic screening instruments for alcohol and other drug use and other psychiatric disorders

In recent years there has been a growing recognition that many people with drug or alcohol problems are also experiencing a range of other psychiatric and psychological problems. The presence of concurrent psychiatric or psychological problems is likely to impact on the success of treatment services. These problems vary greatly, from undetected major psychiatric illnesses that meet internationally accepted diagnostic criteria such as those outlined in the Diagnostic and Statistical Manual (DSM-IV) of the American Psychiatric Association (1994), to less defined feelings of low mood and anxiety that do not meet diagnostic criteria but nevertheless impact on an individual’s sense of wellbeing and affect their quality of life.

Cannabis use and psychosis

This paper reviews evidence on two hypotheses about the relationship between cannabis use and psychosis. The first hypothesis is that heavy cannabis use may cause a cannabis psychosis-a psychosis that would not occur in the absence of cannabis use, the symptoms of which are preceded by heavy cannabis use and remit after abstinence. The second hypothesis is that cannabis use may precipitate schizophrenia, or exacerbate its symptoms. Evaluation of these hypotheses requires evidence of an association between cannabis use and psychosis, that is unlikely to be due to chance, in which cannabis use precedes psychosis, and in which we can exclude the hypothesis that the relationship is due to other factors, such as other drug use, or a personal vulnerability to psychosis. There is some clinical support for the first hypothesis. If these disorders exist they seem to be rare, because they require very high doses of THC, the prolonged use of highly potent forms of cannabis, or a pre-existing (but as yet unspecified) vulnerability. There is more support for the second hypothesis, in that a large prospective study has shown a linear relationship between the frequency with which cannabis has been used by age 18 and the risks over the subsequent 15 years of a diagnosis of schizophrenia. It is still unclear whether this means that cannabis use precipitates schizophrenia, whether it is a form of self-medication, or whether the association is due to the use of other drugs, such as amphetamines, which heavy cannabis users are more Likely to use. There is stronger evidence that cannabis use can exacerbate the symptoms of schizophrenia. Mental health services should identify patients with schizophrenia who use alcohol, cannabis and other drugs and advise them to abstain or to greatly reduce their drug use.

Cannabis use and psychosis: a review of clinical and epidemiological evidence

Objective: This paper evaluates evidence for two hypotheses about the relationship between cannabis use and psychosis: (i) that heavy cannabis use causes a 'cannabis psychosis', i.e, a psychotic disorder that would not have occurred in the absence of cannabis use and which can be recognised by its pattern of symptoms and their relationship to cannabis use; and (ii) that cannabis use may precipitate schizophrenia, or exacerbate its symptoms. Method: Literature relevant to drug use and schizophrenia is reviewed. Results: There is limited clinical evidence for the first hypothesis. If 'cannabis psychoses' exist, they seem to be rare, because they require very high doses of tetrahydrocannabinol, the prolonged use of highly potent forms of cannabis, or a preexisting (but as yet unspecified) vulnerability, or both. There is more support for the second hypothesis in that a large prospective study has shown a linear relationship between the frequency with which cannabis had been used by age 18 and the risk over the subsequent 15 years of receiving a diagnosis of schizophrenia. Conclusions: It is still unclear whether this means that cannabis use precipitates schizophrenia, whether cannabis use is a form of 'self-medication', or whether the association is due to the use of other drugs, such as amphetamines, which heavy cannabis users are more likely to use. There is better clinical and epidemiological evidence that cannabis use can exacerbate the symptoms of schizophrenia.

The relationship between cannabis use and other substance use in the general population

This study examined if (1) there is an association in the general population between cannabis use, DSM-IV abuse and dependence, and other substance use and DSM-IV substance abuse/dependence; (2) if so, is it explained by demographic characteristics or levels of neuroticism? It used data from the Australian National Survey of Mental Health and Well-Being (NSMHWB), a stratified, multistage probability sample of 10641 adults, representative of the general population. DSM-IV diagnoses of substance abuse and dependence were derived using the Composite International Diagnostic Interview (CIDI). There was a strong bivariate association between involvement with cannabis use in the past 12 months and other substance use, abuse and dependence. In particular, cannabis abuse and dependence were highly associated with increased risks of other substance dependence. These associations remained after including other variables in multiple regression. Cannabis use without disorder was strongly related to other drug use, an association that was not explained by other variables considered here. The high likelihood of other substance use and substance use disorders needs to be considered among persons seeking treatment for cannabis use problems. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

Cannabis use and cancer (Editorial)

No Abstract

Patterns of co-morbidity between alcohol use and other substance use in the Australian population

The present study describes patterns of co-morbidity between alcohol use and other substance use problems in the Australian population using data from the 1997 National Survey of Mental Health and Well-Being. Multiple regression analyses examined whether the observed associations between alcohol and other drug use disorders were explained by other variables, including demographic characteristics and neuroticism. We also assessed whether the presence of co-morbid substance use disorders affected treatment seeking for a mental health problem. Alcohol use was related strongly to the use of other substances. Those who did not report alcohol use within the past 12 months were less likely to report using tobacco, cannabis, sedatives, stimulants or opiates. Higher rates again were observed among those with alcohol use disorders: half (51%) of those who were alcohol-dependent were regular tobacco smokers, one-third had used cannabis (32%); 15% reported other drug use; 15% met criteria for a cannabis use disorder and 7% met criteria for another drug use disorder. These associations were not accounted for by the demographic and other variables considered here. Co-morbid substance use disorders (sedatives, stimulants or opioids) predicted a high likelihood of seeking treatment for a mental health problem among alcohol-dependent people.