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The effect of adding an alcohol to surfactant systems depends much on the alcohol chain length. Investigations on the effect of alcohols in micellar systems point out that medium-chain alcohols are appreciably incorporated in the micellar phase whereas short-chain alcohols are localized mainly in the aqueous phase. Nonetheless, penetration of the hydrocarbon chain of alcohols in the micellar shell has been experimentally observed for the entire homologous series of linear 1-alcohols. We present a thermodynamic model in which the alcohol molecules play two roles: cosurfactant and cosolvent. The cosurfactant effect of the alcohols is included by assuming that the alcohol molecules are nonionic surfactants. The cosolvent effect is modeled by accounting for the changes in the free energy to relocate the surfactant tail from the solvent to the aggregate core. The effects of short-chain alcohols in the macroscopic interfacial tension and dielectric constant of the solvent medium are also taken into account. For short-chain alcohols the partition coefficient of the alcohols between water and liquid hydrocarbons provides knowledge of the fraction of the molecules that participate in each function. Our proposed thermodynamic model improves the modeling of the effect of short- and medium-chain alcohols in self-assembly of molecules that are of increasing importance in modern scientific research and technological processes.

Background: The mosquito Aedes aegypti was recently transinfected with a life-shortening strain of the endosymbiont Wolbachia pipientis (wMelPop) as the first step in developing a biocontrol strategy for dengue virus transmission. In addition to life-shortening, the wMelPop-infected mosquitoes also exhibit increased daytime activity and metabolic rates. Here we sought to quantify the blood-feeding behaviour of Wolbachia-infected females as an indicator of any virulence or energetic drain associated with Wolbachia infection., Methodology/principal Findings: In a series of blood-feeding trials in response to humans, we have shown that Wolbachia-infected mosquitoes do not differ in their response time to humans, but that as they age they obtain fewer and smaller blood meals than Wolbachia-uninfected controls. Lastly, we observed a behavioural characteristic in the Wolbachia infected mosquitoes best described as a "bendy" proboscis that may explain the decreased biting success., Conclusions/significance: Taken together the evidence suggests that wMelPop infection may be causing tissue damage in a manner that intensifies with mosquito age and that leads to reduced blood-feeding success. These behavioural changes require further investigation with respect to a possible physiological mechanism and their role in vectorial capacity of the insect. The selective decrease of feeding success in older mosquitoes may act synergistically with other Wolbachia-associated traits including life-shortening and viral protection in biocontrol strategies.

Background: Despite governmental and private efforts on providing malaria control, this disease continues to be a major health threat. Thus, innovative strategies are needed to reduce disease burden. The malaria vectors, through the injection of saliva into the host skin, play important role on disease transmission and may influence malaria morbidity. This study describes the humoral immune response against Anopheles (An.) darlingi saliva in volunteers from the Brazilian Amazon and addresses the association between levels of specific antibodies and clinical presentation of Plasmodium (P.) vivax infection., Methods: Adult volunteers from communities in the Rondônia State, Brazil, were screened in order to assess the presence of P. vivax infection by light microscopy and nested PCR. Non-infected volunteers and individuals with symptomatic or symptomless infection were randomly selected and plasma collected. An. darlingi salivary gland sonicates (SGS) were prepared and used to measure anti-saliva antibody levels. Plasma interleukin (IL)-10 and interferon (IFN)-gamma levels were also estimated and correlated to anti-SGS levels., Results: Individuals infected with P. vivax presented higher levels of anti-SGS than non-infected individuals and antibody levels could discriminate infection. Furthermore, anti-saliva antibody measurement was also useful to distinguish asymptomatic infection from non-infection, with a high likelihood ratio. Interestingly, individuals with asymptomatic parasitaemia presented higher titers of anti-SGS and lower IFN-gamma/IL-10 ratio than symptomatic ones. In P. vivax-infected asymptomatic individuals, the IFN-gamma/IL-10 ratio was inversely correlated to anti-SGS titers, although not for while in symptomatic volunteers., Conclusion: The estimation of anti-An. darlingi antibody levels can indicate the probable P. vivax infection status and also could serve as a marker of disease severity in this region of Brazilian Amazon.

Context and Objective: Cancer of the uterine cervix is still very common in Brazil. It is important to evaluate factors that influence its prognosis. The aim here was to analyze the prevalence of prognostic anatomoclinical factors among patients with carcinoma of the uterine cervix undergoing radical hysterectomy., Design and Setting: Cross-sectional study on 301 patients with invasive carcinoma of the uterine cervix who underwent Level III Piver-Rutledge hysterectomy surgery at São Marcos Hospital., Methods: The following variables were analyzed: age, histological type, degree of differentiation, invasion of lymphatic, vascular and perineural space, lymph node metastasis, distance to nearest margin, tumor invasion depth, vaginal cuff size, largest diameter of the tumor, presence of necrosis and surgical margin involvement. Descriptive statistics, multiple regression analysis, Kaplan-Meier survival curves and the log-rank test were performed. A significance level of 5% was used., Results: The mean age was 48.27 years. The following were not important for the prognosis, in relation to survival analysis: degree of differentiation and tumor invasion depth; presence of lymphatic, blood and perineural invasions; distance to nearest margin; and vaginal cuff size. Tumor size (P < 0.036), presence of lymph node metastasis (P < 0.0004), necrosis (P < 0.05) and surgical margin involvement (P < 0.0015) presented impacts on survival. The overall survival with 98 months of follow-up was 88.35%., Conclusion: The most prevalent prognostic factors were the presence of lymph node metastasis, tumor size and surgical margin involvement.

Biomphalaria tenagophila Taim lineage has proved to be consistently resistant to Schistosoma mansoni. Several published works have shown that this resistance is due to the innate defence system of that strain, and in cross-breedings with susceptible strains the Taim lineage presents dominant character. These findings led to the hypothesis that, introducing this strain in areas where transmission of schistosomiasis is maintained by this species, the introduced lineage would perform cross-breeding with the local snails, thus generating offsprings resistant to the parasites. The perspectives of the proposed approach, as well as some preliminary results and problems related to the first introduction without a previous use of molluscicide are discussed.

The main vectors of malaria in Brazil are Anopheles darlingi, An. aquasalis, and some species of the An. albitarsis complex, whereas others have questionable importance with regard to the disease transmission. To identify these vectors in the State of Pará, Brazil, in a high-prevalence P. falciparum area, 565 anophelines were captured and identified while the seasonal variation and daily biting activity were determined. Of the seven anopheline species (An. strodei, An. albitarsis s.l., An. rondoni, An. darlingi, An. triannulatus, An. oswaldoi, and An. nuneztovari), the plasmodia circumsporozoite protein (CSP) was detected in three of them, with a total infection rate of 6.2%. An. darlingi was the most prevalent species (22.4%), followed by An. albitarsis (5.2%) and An. rondoni (3.6%). An. rondoni was found to be infected for the first time, which was also confirmed through PCR. This result possibly represents a new malaria vector based on its highest frequency, biting and seasonal activities in the peak of malaria transmission.

The genetic manipulation of mosquito vectors is an alternative strategy in the fight against malaria. It was previously shown that bee venom phospholipase A2 (PLA2) inhibits ookinete invasion of the mosquito midgut although mosquito fitness was reduced. To maintain the PLA2 blocking ability without compromising mosquito biology, we mutated the protein-coding sequence to inactivate the enzyme while maintaining the protein's structure. DNA encoding the mutated PLA2 (mPLA2) was placed downstream of a mosquito midgut-specific promoter (Anopheles gambiae peritrophin protein 1 promoter, AgPer1) and this construct used to transform Aedes fluviatilis mosquitoes. Four different transgenic lines were obtained and characterized and all lines significantly inhibited Plasmodium gallinaceum oocyst development (up to 68% fewer oocysts). No fitness cost was observed when this mosquito species expressed the mPLA2.

While seeking strategies for interfering with Plasmodium development in vertebrate/invertebrate hosts, we tested the activity of gomesin, an antimicrobial peptide isolated from the hemocytes of the spider Acanthoscurria gomesiana. Gomesin was tested against asexual, sexual and pre-sporogonic forms of Plasmodium falciparum and Plasmodium berghei parasites. The peptide inhibited the in vitro growth of intraerythrocytic forms of P. falciparum. When gomesin was added to in vitro culture of P. berghei mature gametocytes, it significantly inhibited the exflagellation of male gametes and the formation of ookinetes. In vivo, the peptide reduced the number of oocysts of both Plasmodium species in Anopheles stephensi mosquitoes, and did not appear to affect the mosquitoes. These properties make gomesin an excellent candidate as a transmission blocking agent for the genetic engineering of mosquitoes.

The technique to generate transgenic mosquitoes requires adaptation for each target species because of aspects related to species biology, sensitivity to manipulation and rearing conditions. Here we tested different parameters on the microinjection procedure in order to obtain a transgenic Neotropical mosquito species. By using a transposon-based strategy we were able to successfully transform Aedes fluviatilis (Lutz), which can be used as an avian malaria model. These results demonstrate the usefulness of the piggyBac transposable element as a transformation vector for Neotropical mosquito species and opens up new research frontiers for South American mosquito vectors.

One potential strategy for the control of malaria and other vector-borne diseases is the introduction into wild vector populations of genetic constructs that reduce vectorial capacity. An important caveat of this approach is that the genetic construct should have minimal fitness cost to the transformed vector. Previously, we produced transgenic Anopheles stephensi expressing either of two effector genes, a tetramer of the SM1 dodecapeptide or the phospholipase A2 gene (PLA2) from honeybee venom. Mosquitoes carrying either of these transgenes were impaired for Plasmodium berghei transmission. We have investigated the role of two effector genes for malaria parasite blockage in terms of the fitness imposed to the mosquito vector that expresses either molecule. By measuring mosquito survival, fecundity, fertility, and by running population cage experiments, we found that mosquitoes transformed with the SM1 construct showed no significant reduction in these fitness parameters relative to nontransgenic controls. The PLA2 transgenics, however, had reduced fitness that seemed to be independent of the insertion site of the transgene. We conclude that the fitness load imposed by refractory gene(s)-expressing mosquitoes depends on the effect of the transgenic protein produced in that mosquito. These results have important implications for implementation of malaria control via genetic modification of mosquitoes.

The aim of this study was to report the effectiveness of laser therapy applied to traumatic labial injury of patients with spastic cerebral palsy. We report two cases of patients with internal mucosa and lower lip traumatism caused by oral reflex automatism with spastic tonic bite and lower lip interposition. One patient presented extensive lower lip ulceration, loss of tissue, crusty and hemorrhagic areas, with increasing pain and spasticity. The other patient presented local congestion signs, extremely enlarged tissue growth and increased labial volume. Laser therapy was applied to all injured areas, with a low-potency diode InGaAlP laser [685 nm Quasar (Dentoflex), 190 J/ cm2, with a 24-h interval between the first and second administration, and a 7-day interval between the two subsequent ones. At first re-evaluation, 24 h later, there was a striking reduction in inflammation, a decrease in vascular congestion, and a reduction of the ulcerated area with spasticity and pain reduction. At the 14-day re-evaluation, significant clinical differences in the advanced healing process were seen. Low-intensity laser showed to be effective in traumatic soft tissue treatment in cerebral palsy patients by accelerating the healing process, reducing secondary contamination, promoting analgesia; thus, it can be an important tool in the treatment of these patients.

Malaria inflicts an enormous toll in human lives and this burden is increasing. Present means to fight the disease, such as drugs and insecticides, are insufficient. Moreover, an effective vaccine has not yet been developed. This review examines an alternative strategy for malaria control, namely the genetic modification of mosquitoes to make them inefficient vectors for the parasite. The article summarises progress made toward the development of transposable element vectors for germ line transformation and the search for mosquito markers of transformation. Also reviewed is the search for anti-malarial effector genes whose products can inhibit development of the parasite in the mosquito with minimal fitness burden. While much progress has been made, much work remains to be done. Future research directions are discussed.

Malaria kills millions of people every year, and new control measures are urgently needed. The recent demonstration that (effector) genes can be introduced into the mosquito germ line to diminish their ability to transmit the malaria parasite offers new hope toward the fight of the disease (Ito, J., Ghosh, A., Moreira, L. A., Wimmer, E. A. & Jacobs-Lorena, M. (2002) Nature, 417, 452-455). Because of the high selection pressure that an effector gene imposes on the parasite population, development of resistant strains is likely to occur. In search of additional antiparasitic effector genes, we have generated transgenic Anopheles stephensi mosquitoes that express the bee venom phospholipase A2 (PLA2) gene from the gut-specific and blood-inducible Anopheles gambiae carboxypeptidase (AgCP) promoter. Northern blot analysis indicated that the PLA2 mRNA is specifically expressed in the guts of transgenic mosquitoes with peak expression at approximately 4 h after blood ingestion. Western blot and immunofluorescence analyses detected PLA2 protein in the midgut epithelia of transgenic mosquitoes from 8 to 24 h after a blood meal. Importantly, transgene expression reduced Plasmodium berghei oocyst formation by 87% on average and greatly impaired transmission of the parasite to naive mice. The results indicate that PLA2 may be used as an additional effector gene to block the development of the malaria parasite in mosquitoes.

Malaria continues to kill millions of people every year and new strategies to combat this disease are urgently needed. Recent advances in the study of the mosquito vector and its interactions with the malaria parasite suggest that it may be possible to genetically manipulate the mosquito in order to reduce its vectorial capacity. Here we review the advances made to date in four areas: (1) the introduction of foreign genes into the mosquito germ line; (2) the characterization of tissue-specific promoters; (3) the identification of gene products that block development of the parasite in the mosquito; and (4) the generation of transgenic mosquitoes impaired for malaria transmission. While initial results show great promise, the problem of how to spread the blocking genes through wild mosquito populations remains to be solved.

Malaria is estimated to cause 0.7 to 2.7 million deaths per year, but the actual figures could be substantially higher owing to under-reporting and difficulties in diagnosis. If no new control measures are developed, the malaria death toll is projected to double in the next 20 years. Efforts to control the disease are hampered by drug resistance in the Plasmodium parasites, insecticide resistance in mosquitoes, and the lack of an effective vaccine. Because mosquitoes are obligatory vectors for malaria transmission, the spread of malaria could be curtailed by rendering them incapable of transmitting parasites. Many of the tools required for the genetic manipulation of mosquito competence for malaria transmission have been developed. Foreign genes can now be introduced into the germ line of both culicine and anopheline mosquitoes, and these transgenes can be expressed in a tissue-specific manner. Here we report on the use of such tools to generate transgenic mosquitoes that express antiparasitic genes in their midgut epithelium, thus rendering them inefficient vectors for the disease. These findings have significant implications for the development of new strategies for malaria control.

Genetic modification of the vectorial capacity of mosquito vectors of human disease requires promoters capable of driving gene expression with appropriate tissue and stage specificity. We report on the characterization in transgenic Aedes aegypti of two mosquito gut-specific promoters. A 1.4-kb DNA fragment adjacent to the 5' end of the coding region of the Ae. aegypti carboxypeptidase (AeCP) gene and a corresponding 3.4-kb DNA fragment at the 5' end of the Anopheles gambiae carboxypeptidase (AgCP) gene were linked to a firefly luciferase reporter gene and introduced into the Ae. aegypti germ line by using Hermes and mariner (Mos1) transposons. Six independent transgenic lines were obtained with the AeCP construct and one with the AgCP construct. Luciferase mRNA and protein were abundantly expressed in the guts of transgenic mosquitoes in four of the six AeCP lines and in the AgCP line. Expression of the reporter gene was gut-specific and reached peak levels at about 24 h post-blood ingestion. The AeCP and AgCP promoters can be used to drive the expression of genes that hinder parasite development in the mosquito gut.

OBJECTIVE: To emphasize important aspects for the diagnosis and approach of patients with history of child abuse, related with the Munchausen Syndrome by proxy, and its variant, Hypochondriases by proxy. METHODS: The authors describe two cases followed in the Pediatric Service in a terciary hospital of Salvador, Bahia, in which they found aspects of the medical history and physical examination of these children and in the mothers' behavior compatible with Munchausen by proxy (Factitious disorder by proxy). RESULTS: In the two cases presented, we observed a standard in the clinical history, described as recurrent inpatient and outpatient medical support, through the last three years, without the identification of abnormal results. These facts do not decreased the certainty of the mothers about their children's disease (hypochondriases by proxy). Furthermore we observed cooperation on the part of the children by incorporating the role of the sick one, which made their school and social adaptation more difficult. CONCLUSIONS: The pediatrician must be aware of the diagnosis of Munchausen Syndrome by Proxy and its variation, hypochondriases by proxy, in those cases of unsuitable and recurrent disease, lack of symptoms and signs in the absence of parents, and diagnostic methods with meaningless results. When absolutely certain about diagnosis, the physician must establish the risk for the child (increased mortality in these cases) and suggest psychotherapy for the mother or perpetrator.

The success of international initiatives for the eradication of measles depends in large part on knowledge about vaccination. In 1992, a cross-sectional study was carried out to evaluate knowledge about measles vaccine among pediatricians in the Brazilian city of Salvador, Bahia. Of the 506 pediatricians residing in the city, 299 (59%) could be located and responded to a questionnaire containing 15 questions that posed hypothetical situations regarding indications and contraindications for this vaccine. The average number of correct responses was 9.3 out of 15, which illustrates the pediatricians' poor knowledge of measles vaccine. Conditions commonly seen in pediatric practice in Brazil--malnutrition, upper respiratory tract infection, diarrhea, and prematurity--were often erroneously considered contraindications for immunization. More than half (62%) of the pediatricians did not know the correct way to administer the vaccine. Knowledge about the vaccine did not differ according to the length of time that had elapsed since the physicians' university training in pediatrics or as a result of working in health centers operated by the State Health Secretariat. University professors, pediatricians with a postgraduate degree, and those pursuing postgraduate studies scored slightly higher than the rest. These results point to the need to strengthen training on measles vaccination in medical schools and programs of continuing education for pediatricians.

The effect of feeding on Eucalyptus leaves of Tynacantha marginata (Heteroptera: Pentatomidae) was studied in Brazil. The use of this plant as a complementary food source for the predatory bug increased its oviposition period, generation time, and net reproductive rate. Eucalyptus leaves apparently had no influence on the survival and development of T. marginata.