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Background: This cross‐sectional study investigated the association between chronotype, food craving and weight gain in pregnant women. Methods: In total, 245 pregnant women attending the public health service in Brazil were included. Chronotype was derived from the time of mid‐sleep time on free days, with a further correction for calculated sleep debt, and higher scores on this variable indicate a tendency to eveningness. A Food Craving Questionnaire Trait and State assessment was performed, and weight gain was calculated. Generalised linear models were used to determine the association between the variables under analysis. Results: Evening types presented higher anticipation of relief from negative states and feelings as a result of eating as a usual behaviour compared to morning (P = 0.013) and non‐evening types (P = 0.028); less intense desire to eat as a sporadic behaviour compared to morning (P = 0.012) and non‐evening types (P = 0.009); and less anticipation of positive reinforcement that may result from eating as a sporadic behaviour than non‐evening types (P = 0.022). We also found a significant association between chronotype score and anticipation of relief from negative states and feelings as a result of eating (P = 0.004); anticipation of positive reinforcement that may result from eating (P = 0.013) as a usual behaviour; weight gain during the early gestational period (P = 0.024); and intense desire to eat (P = 0.045) as a sporadic behaviour. Conclusions: We conclude that evening chronotype was associated with the food craving trait. Pregnant women who tend to eveningness are more likely to gain weight in the early gestational period. [ABSTRACT FROM AUTHOR]

In this study, we described, for the first time, specific aspects of an anti- Leishmania immune response in a Brazilian Xakriabá indigenous community. Induction of an intracellular NO pathway, triggered by the binding of IgE to CD23 receptor in IFN- γ/ IL-4 cytokines environment, was evaluated in localized cutaneous leishmaniasis ( LCL) carriers and positive Montenegro skin test ( MST) individuals without skin lesion ( MT+ SL−). Our data demonstrated that the higher frequency of CD23+ CD14+ monocytes and the increased serum levels of IgE observed in the LCL group were even higher in LCL carriers with late lesions ( LCL≥60). Furthermore, patients with LCL presented increased NO production after Leishmania (Viannia) braziliensis stimulation and this NO profile was independent of the time of the lesion (recent LCL<60 or late LCL≥60). We also showed that the increased frequency of IFN-γ+ and IL-4+ CD4+ T cells is related to the MT+ SL− group. The results of biomarker signature curves demonstrated that in the MT+ SL− group, the index signature was characterized by DAF-2T+ CD14+/ IL-4+ CD8+/ IFN-γ+ CD4+/ IL-4+ CD4+. On the other hand, the LCL group presented a higher index of DAF-2T+ CD14+/ CD23+ CD14+/ IL-4+ CD8+, associated with a lower index of IFN-γ+ CD8+. Considering the time of lesion, data analysis demonstrated that the main differences observed were highlighted in LCL<60 patients, with a higher index of CD23+ CD14+, which was also present in LCL≥60 patients. In conclusion, our data suggest that the protective immune response involving CD23-IgE-mediated NO release is a hallmark of patients with LCL. However, in MT+ SL− individuals, another different leishmanicidal mechanism seems to be involved. [ABSTRACT FROM AUTHOR]

Oral tolerance is a phenomenon that may occur in animals exposed to soluble antigens for the first time by the oral route. In the present study, we show that oral tolerance against ovalbumin (Ova) can be obtained after intragastric administration of the antigen in the presence of free residues of palmitate. On the other hand, oral tolerance induction is blocked when the residues of palmitate are covalently bound to the antigen (Ova-palmitate conjugates). We have also noticed that oral administration of Ova-palmitate conjugates can boost and/or prime experimental animals for Ova-specific cellular and humoral systemic immune responses. Oral treatment with the conjugates also induces the production of local secretory immunoglobulin A (IgA) as measured in intestinal washes. Furthermore, Ova-palmitate given orally can inhibit oral tolerance induction by naïve Ova. [ABSTRACT FROM AUTHOR]

A palmitate-conjugate derivative of ovalbumin which can be inserted into the membrane of B cells has been prepared. The ability of these cells to act as antigen-presenting cells for specific T lymphocytes obtained from immunized mice was tested. It was found that the conjugates were more efficiently processed and presented than the naive form of the antigen. Palmitate-conjugated antibodies specific to ovalbumin were also inserted into the cell membrane of normal B lymphocytes. These cells were pulsed with the antigen and tested as antigen-presenting cells for T cells obtained from immunized mice. The antibody-decorated B cells presented ovalbumin more efficiently than non-decorated controls. Whether antibody-decorated, antigen-pulsed B cells could prime T cells in vivo was investigated. Some priming activity was found. [ABSTRACT FROM AUTHOR]

Palmitate-conjugated monoclonal antibodies specific to ovalbumin were inserted into the cell membrane of normal resting B cells and LPS-activated blasts. These two decorated B cells were tested for their ability to act as antigen-presenting cells for ovalbumin-specific I-Ad-restricted T-cell hybridomas. It was found that the antibody-decorated resting B cells presented antigen more efficiently than non-decotated controls. However, no increment was observed when decorated LPS blasts were compared with nondecorated blasts. This is explained by the fact that the inserted antibodies quickly disappeared from the cell membrane of LPS blasts, while they were retained for a long period in the membrane of resting B cells. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies specific for ovalbumin were conjugated to palmitate and inserted into the membrane of normal spleen B cells. Their presence in the membrane, as well as their ability to bind ovalbumin, was established by immunofluorescence. The so called anti-ovalbumin-'decorated' B cells were tested for their ability to act as antigen-presenting cells for ovalbumin specific I-Ad-restricted T-cell hybridomas. It was found that the antibody-decorated B cells presented antigen more efficiently than non-decorated B cells. [ABSTRACT FROM AUTHOR]

We have investigated the ability of different cells from non-immunized mice of the BALB/c strain to present antigen to two ovalbumin-specific I-Ad-restricted T hybridomas. Lipopoiysaccbaride-activated B-cell blasts were found to be the most efficient antigen-presenting cells. Purified small and dense splenic B cells also stimulated the hybridomas, although not to the same extent as the activated blasts, but comparable to non-fractionated spleen cells, Glutaraldehyde-treated B cells failed to present antigen, whereas F(ab')2 anti-mouse IgM-treated B cells exhibited markedly increased ability to present antigen. Using flow cytometry, we further purified the resting B cells by sorting the small lymphocytes to ensure that the ability of these cells to activate the hybridomas was not due to contamination with large non-resting B ceils. The sorted small B cells retained the ability of antigen presentation. Their resting state was confirmed by the fact that they did not incorporate [3H]-thymidine as shown by autoradiographic analysis. [ABSTRACT FROM AUTHOR]

We do not agree with the analysis of Langman and Cohn on the function of Ig receptors. We have reviewed the available literature regarding anti-Ig activation of B cells and found it contradictory and unconvincing. We have presented experimental evidence on the inability of Ig receptors on B cells to mediate activation or tolerogenic signals. We suggest that the Ig receptors serve to focus antigen to specific B cells so the B cells can be activated by TI antigens or helper T cells. The Ig molecules also bind foreign antigen and thereby initiate internalization and antigen processing. The processed peptides are exported to the membrane, where they associate with MI-IC class!! antigens, thus transforming B cells into efficient antigen-presenting cells. [ABSTRACT FROM AUTHOR]

Oral tolerance is a phenomenon that may occur in animals exposed to soluble antigens for the first time by the oral route. In the present study, we show that oral tolerance against ovalbumin (Ova) can be obtained after intragastric administration of the antigen in the presence of free residues of palmitate. On the other hand, oral tolerance induction is blocked when the residues of palmitate are covalently bound to the antigen (Ova-palmitate conjugates). We have also noticed that oral administration of Ova-palmitate conjugates can boost and/or prime experimental animals for Ova-specific cellular and humoral systemic immune responses. Oral treatment with the conjugates also induces the production of local secretory immunoglobulin A (IgA) as measured in intestinal washes. Furthermore, Ova-palmitate given orally can inhibit oral tolerance induction by naïve Ova. [ABSTRACT FROM AUTHOR]

Estimating seroprevalence and vaccination coverage against COVID-19 is crucial to the development of well-targeted public health policies at the local level. Here, we estimated seroprevalence and vaccination coverage in a lower-middle-class population in Brazil. We conducted an observational, cross-sectional, population-based survey from 24 September to 19 December 2021. CMIA tests were used to detect anti-SARS-CoV-2 IgG against the N-protein. The overall seroprevalence was 24.15% (177/733), and vaccination coverage was 91.40% (670/733); 72.09% (483/670) were fully vaccinated. Among vaccinated participants, seroprevalence was 24.77% (95% CI 21.50-28.04; 166/670), with a prevalence ratio (PR) of 1.03 (95% CI 0.98-1.08; p -value 0.131). Among participants who received an mRNA vaccine with S-based epitope (485), seroprevalence was 16.29% (95% CI 13.04-19.85; 79/485). Among unvaccinated participants, seroprevalence was 17.46% (95% CI 10.04-28.62; 11/63). Finally, in spite of the political climate and other possible causes for vaccine hesitancy, the positive Brazilian culture towards vaccination might have curbed hesitancy.

Ultra-rare biallelic pathogenic variants in geranylgeranyl diphosphate synthase 1 (GGPS1) have recently been associated with muscular dystrophy/hearing loss/ovarian insufficiency syndrome. Here, we describe 11 affected individuals from four unpublished families with ultra-rare missense variants in GGPS1 and provide follow-up details from a previously reported family. Our cohort replicated most of the previously described clinical features of GGPS1 deficiency; however, hearing loss was present in only 46% of the individuals. This report consolidates the disease-causing role of biallelic variants in GGPS1 and demonstrates that hearing loss and ovarian insufficiency might be a variable feature of the GGPS1-associated muscular dystrophy., (© 2022 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

Leishmaniasis is a highly diverse group of diseases caused by kinetoplastid of the genus Leishmania. These parasites are taxonomically diverse, with human pathogenic species separated into two subgenera according to their development site inside the alimentary tract of the sand fly insect vector. The disease encompasses a variable spectrum of clinical manifestations with tegumentary or visceral symptoms. Among the causative species in Brazil, Leishmania (Leishmania) amazonensis is an important etiological agent of human cutaneous leishmaniasis that accounts for more than 8% of all cases in endemic regions. L. (L.) amazonensis is generally found in the north and northeast regions of Brazil. Here, we report the first isolation of L. (L.) amazonensis from dogs with clinical manifestations of visceral leishmaniasis in Governador Valadares, an endemic focus in the southeastern Brazilian State of Minas Gerais where L. (L.) infantum is also endemic. These isolates were characterized in terms of SNPs, chromosome and gene copy number variations, confirming that they are closely related to a previously sequenced isolate obtained in 1973 from the typical Northern range of this species. The results presented in this article will increase our knowledge of L. (L.) amazonensis-specific adaptations to infection, parasite survival and the transmission of this Amazonian species in a new endemic area of Brazil.

Phlebotominae sand flies are of medical importance because they are vectors of human pathogens, such as protozoa of the genus Leishmania Ross, etiological agent of American cutaneous leishmaniasis (ACL). In Lábrea, a municipality in the state of Amazonas, Brazil, ACL is primarily associated with subsistence activities, such as collection and extraction of forest products, undertaken by both indigenous and nonindigenous people. Data on ACL in indigenous populations are scarce, such that there is little information on the identity of the etiologic agent(s), reservoir host(s) and insect vector(s). The aim of this work was to study the sand fly fauna collected during an 8-d surveillance of different habitats in the Indigenous Reserve Caititu, Lábrea. In total, 1,267 sand flies were collected in different habitats for eight consecutive days, of which 819 (64.6%) were females and 448 (35.4%) males, from 10 genera and 32 species. The most abundant genera were Psychodopygus (34.3%), Trichophoromyia (22.9%), and Nyssomyia (15.3%). The most abundant species were Trichophoromyia ubiquitalis (Mangabeira) (n = 235, 18.5%), Psychodopygus davisi (Root) (n = 228, 18.0%) and Nyssomyia antunesi (Coutinho) (n = 135, 10.7%). Direct sequencing of polymerase chain reaction products demonstrated the presence of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis in the following species of sand flies: Evandromyia apurinan (Shimabukuro, Silveira, & Silva), Nyssomyia umbratilis (Ward & Fraiha), Nyssomyia yuilli yuilli (Young & Porter), Ps. davisi, Sciopemyia servulolimai (Damasceno & Causey), and Th. ubiquitalis. The presence of natural infection by Leishmania detected in the sand fly species investigated in this study suggests their possible role in the transmission cycle of ACL in the studied area., (© 2014 Entomological Society of America.)

We made a molecular study of 40 opossums, Didelphis albiventris, from an urban fragment of the Atlantic Rainforest in southeastern Brazil, analyzing a 653-bp sequence of cytochrome c oxidase, subunit I. We found three close connected haplotypes, with low nucleotide diversity and a haplotype diversity of 59.1% and confirmed sympatry between D. albiventris and D. aurita in this region. The clear phylogenetic separation shows the appropriateness of DNA barcode identification methodology for effectively discriminating between these opossum species.

Oral administration of protein antigens, such as ovalbumin, may result in induction of either tolerance or immunization. To avoid oral tolerance, there are new strategies to protect the antigens from degradation within the gastrointestinal tract and to allow them to reach inductive immunological sites. One such strategy is the usage of liposomes. Different parameters may influence the stability of liposomes in the gastrointestinal tract. Herein, we studied the immunological consequences of oral administration of liposome-encapsulated ovalbumin in different strains of mice using different liposomes. Our data demonstrated that ovalbumin liposomes improved the induction of oral immunization and the degree of improvement depended on the liposome type and on the strain of mice used. The mechanism responsible for this differential effect of liposomes depended on the site of antigen release and absorption. Therefore, some liposomes might be suitable as adjuvants for oral immunization, others for oral tolerance induction.

Babesia bigemina and Babesia bovis are intra-erythrocytic protozoan parasites transmitted by ticks to cattle in which they induce babesiosis, a disease that resembles human malaria. Anemia, caused by the destruction of non-infected erythrocytes, is a critical feature of the disease. Anti-erythrocyte antibodies could be one of the explanations for such destruction. These antibodies are found in the sera of dogs and mice respectively infected with B. gibsoni and B. rodhaini. However, data concerning the presence of anti-erythrocyte antibodies in the sera of infected cattle are not conclusive. In the present study, we made an attempt to detect anti-erythrocyte antibodies from the sera of cattle naturally infected with B. bigemina. Erythrocytes from a non-infected calf were used in ELISA reaction for the detection of antibodies from samples. Results confirmed the presence of anti-erythrocytes antibodies in higher amounts in the serum of infected cattle. In order to correlate this increment with the parasite, anti-erythrocyte antibodies from the sera from infected calves were purified, coupled to a Sepharose-4B column and than used for anti-idiotypic antibodies purification. These antibodies were found to react with the parasites, suggesting a correlation between both anti-parasite and anti-erythrocyte antibodies.

The history and present situation of Chagas' disease in Lassance (the county where Carlos Chagas discovered American trypanosomiasis) were studied through a historical analysis and clinical and epidemiological research performed from 1999 to 2001. Lassance was an important focus of Chagas' disease from Carlos Chagas up until the 1980's, because of intensive infestation in dwellings by Panstrongylus megistus and Triatoma infestans, two important species which were efficiently controlled in the last twenty years. Human Chagas' disease was important in the past but today is only residual, affecting basically the more elderly age groups. The general prevalence is about 5.03% and no infected individuals are found below 20 years of age. The clinical and epidemiologic profile of the seropositive individuals studied is that expected in areas with interrupted transmission, most of these presenting the indeterminate or benign cardiac form of chronic Chagas' disease. Some cases of digestive Chagas' disease also seem to exist. Mortality due to the disease is still significant, affecting chiefly older age groups. The municipality still remains infested by Triatoma sordida, in low densities and high dispersion, non infected by T. cruzi and restricted to peridomestic foci. In conclusion, Lassance is now free of Chagas' disease transmission and must improve medical attention for the remaining infected individuals, as well as to maintain a permanent epidemiological surveillance against native Triatominae.

We detected an outbreak of American cutaneous leishmaniasis in the Jequitinhonha River Valley, Minas Gerais, Brazil. Clinical and epidemiological aspects were studied for a period of two years. Data include results of physical examinations, Montenegro skin test and serology. In total 72 of the 299 individuals evaluated presented active lesions. Only one case out of these 72 patients showed the mucosal form of the disease. The precarious sanitary conditions, low educational level and low income found in the population studied demonstrated that, as with the other parasitic diseases, cutaneous leishmaniasis occurs with greater frequency in needy populations. A canine serological survey detected 20.3% (30/148) of dogs reactive to the Leishmania antigen. Lutzomyia intermedia was the predominant phlebotomine species and the majority of the specimens (84.9%) were captured in the peridomicile. Four samples from human and three from canine cases were isolated and characterised by PCR and isoenzymes as being Leishmania (Viannia) braziliensis. The peridomiciliary nature of the disease is discussed.

Immunological, parasitological, and molecular techniques were applied to blood samples of dogs to diagnose Leishmania infections. In 1997, 644 domestic dogs were studied. Peripheral blood samples were collected for serological diagnosis and detection of Leishmania parasite by polymerase chain reaction (PCR). The indirect immunofluorescence test was positive in 139 (21.6%) of 644 dogs examined. The PCR was performed in 70 blood samples and 3 bone marrow aspirates. A 120-bp fragment specific for Leishmania was present in PCR hybridization analysis of all seropositive samples in the molecular assays. The PCR hybridization test, which used a minicircle of Leishmania chagasi as a probe, was negative in 20 seronegative dogs. These results suggest that a combined PCR-Southern hybridization technique is a highly sensitive approach to diagnose leishmaniasis in dogs, which are a zoonotic reservoir of leishmaniasis for humans.

In the last few years the number of human cases of American visceral leishmaniasis in the Metropolitan Region of Belo Horizonte (MRBH), Minas Gerais, Brazil has increased, indicating an elevation in the transmission rate of the disease. The total number of notified human cases in the MRBH since 1994, when the first case was identified, up to 1999 was 345 of which 223 (65%) were from the city itself, indicating an urbanization of the disease in this region of Minas Gerais. The age distribution of visceral leishmaniasis cases in the MRBH shows a higher prevalence in children from 0-4 years old, responsible for 28.9% of the notifications. Clinical and immunological findings from dogs infected with Leishmania chagasi are described. The majority of these animals showed no sign of the disease. Sera from all infected dogs showed detectable Leishmania-induced high titles of antibodies based on the results of an indirect fluorescent antibody test. Samples of isolated Leishmania from human and dogs were characterized as L. (L.) chagasi by biochemical and molecular techniques.

This study investigated clinical, laboratorial, therapeutic and prognostic aspects of American cutaneous leishmaniasis in Belo Horizonte in 358 patients with cutaneous leishmaniasis (CL) and 25 with mucocutaneous leishmaniasis (MCL). Compared to CL patients, the MCL patients reported longer duration of disease and higher frequency of other diseases, suggesting that debilitation caused by leishmaniasis or other conditions might contribute to activation and/or mucous dissemination of the parasite. The sensitivity of skin test, indirect immunofluorescence reactions and direct detection of parasites was 78.4, 79.3 and 68.3%, respectively. The treatment with meglumine antimoniate presented 100% efficacy, but 59% patients had side-effects. During two years of follow-up, there were 32/318 relapses after successful treatment. Most relapses (31/32) were of CL patients treated with 15 mg Sb5+/kg/day. The negative response to skin test was the only factor associated with a significant threefold increased risk of relapse. Higher dose or longer duration of treatment might improve the prognosis in these patients.

Skin biopsies from 53 patients with American cutaneous leishmaniasis (ACL) from the State of Minas Gerais, Brazil, were used for a characterization of the Leishmania parasites. A pair of primers flanking the conserved region of the Leishmania minicircle kDNA was used to obtain amplified DNA via the polymerase chain reaction. The amplified products were subsequently hybridized with Leishmania subgenus-specific radiolabeled probes. Parasites from 49 out of 53 samples (92.5%) were characterized as belonging to the subgenus Viannia and four (7.5%) as belonging to the subgenus Leishmania. Clinical, epidemiological and molecular evidence allow us to conclude that Leishmania (V.) braziliensis and Leishmania (L.) amazonensis are the species present in the patients studied and that L. (V.) braziliensis is the predominant species in the State of Minas Gerais, Brazil.

A new protocol is described for immunization of outbred Swiss mice. The procedure is based on subcutaneous implantation of antigen-coupled polyester-polyurethane sponges cut into disks of 10 mm in diameter vs 2 mm in thickness. Antigen coupling was performed by overnight incubation of the sponge with a solution of ovalbumin (Ova) (2 mg/ml) diluted in sodium carbonate buffer, pH 9.6. The amount of ovalbumin that was taken up by the sponge was between 71.4 to 82.5 micrograms. This was estimated by comparing the Ova absorbance at 280 nm in coating buffer solutions before and after incubation. To compare the efficiency of the proposed method, experimental groups immunized with the antigen in the presence of adjuvants (10 micrograms in Al(OH)3 or 100 micrograms in complete Freund's adjuvant (CFA)) were run in parallel. The data obtained after the 3rd week of immunization indicate that both cellular and humoral immune responses were achieved. These were assayed by antigen-induced footpad swelling and ELISA (specific antibodies), respectively. The levels of both immune responses elicited were similar to the responses observed in mice immunized with ovalbumin in the presence of Al(OH)3. The method might represent an advantage when immunizing with pathogenic antigens. Preliminary experiments have suggested that the antigen remains immobilized or bound to the sponge for a long period of time, since there is an increment on the cell population inside the sponges after boosting the animals. If so, the undesirable effects of immunization would be reduced.

Oral tolerance is a phenomenon that may occur in animals exposed to protein antigens for the first time by the oral route. They become unable to produce immune responses at the levels normally observed when they are immunized parenterally with antigen in the presence of adjuvants. Lipids have been used as adjuvants for both parenteral and oral immunization. In the present study we coupled ovalbumin with palmitate residues by incubating the protein with the N-hydroxysuccinimide palmitate ester and tested the preparation for its ability to induce oral tolerance. This was performed by giving 20 mg of antigen to mice by the oral route 7 days prior to parenteral immunization in the presence of A1(OH)3. Mice were bled one week after receiving a booster that was given 2 weeks after primary immunization. Specific antibodies were detected by ELISA. Despite the fact that the conjugates are as immunogenic as the unmodified protein when parenterally injected in mice, they failed to induce oral tolerance. This discrepancy could be explained by differences in the intestinal absorption of the two forms of the antigen. In fact, when compared to the non-conjugated ovalbumin, a fast and high absorption of the lipid-conjugated form of ovalbumin was observed by "sandwich" ELISA.

The development of four isolates of Leishmania from foci of American cutaneous leishmaniasis was studied in Lutzomyia longipalpis. The suggestion that the differences in the development of the Leishmania in the invertebrate host are of great taxonomic significance was confirmed. The pattern of development of three strains was typical of parasites of the subgenus Leishmania, the other was similar to Leishmania of the subgenus Viannia. The identification of the strains using other criteria is in agreement with biological characterization. The results show that the morphological and morphometric study of promastigotes do not clearly define the taxonomic position of the parasites but other studies are needed to confirm this.

In order to characterize the epidemiology of American Cutaneous Leishmaniasis (ACL) in a periurban area of the municipality of Sabará in the metropolitan region of Belo Horizonte (MRBH), an area until then considered free of the disease, a cross sectional survey was undertaken in 1990. The survey of the population consisted of 1119 interviews and 881 clinical examinations using Montenegro's skin test (MST). A low prevalence (3.7%) of positive MST was encountered. The disease had been occurring in the area for about 20 years in the form of sporadic cases. The predominant species of sandfly both in domestic areas and nearby areas of secondary vegetation was Lutzomyia whitmani. A canine survey of delayed hypersensitivity to the antigen P10,000 identified only one dog with a positive reaction out of 113 examined. The transmission of ACL in MRBH was confirmed. The occurrence of the disease in women, children and individuals with no contact with forest areas as well as the presence of potential vector species in the domiciliar environment, suggests the transmission of the disease in this environment.

We have introduced some modifications in the technique called "cell decoration" in order to increase the amount of lipid-conjugated antibodies which can be incorporated into the membrane of B cells. As shown by FACS analysis, we have obtained an approximately 4-fold increment in the amount of specific antibodies incorporated into the cell membrane. The procedure, which consists of successive changes of the medium that contains the lipid-conjugated antibodies, avoided changes on parameters that interfere with cell viability. The proposed modification resulted in an approximately 2-fold enhancement of the ability of decorated B cells to act as antigen presenting cells for specific T hybridomas.

The effect of deltamethrin of the sandfly population in a focus of American Cutaneous Leishmaniasis in Viana, Espírito Santo State is described. The phlebotomine population density was determined inside and outside houses during a one year period in a treated and untreated area. The results showed a significant reduction in the number of sandflies inside houses in the treated area compared with both the untreated area and the same area before spraying. Despite having a residual action for 12 months after spraying the insecticide was ineffective outside houses. It is concluded therefore that deltamethrin is an efficient insecticide for reducing the number of phlebotomine sandflies inside houses.

By centrifuging heparinised human blood through a discontinuous Ficoll-Hypaque density gradient, it is possible to separate simultaneously mononuclear cells, neutrophils, and eosinophils.

Granulocytes and mononuclear cells from normal subjects are able to kill Schistosoma mansoni schistosomula in the presence of human complement in vitro. In contrast, mononuclear cells from chronic schistosomiasis patients failed to kill the parasites. The relative efficiencies expressed in terms of the mean percentage killing of schistosomula for 15 experiments were 50.5 +/- 3.2 and 49.7 +/- 3.5 for granulocytes from normal and infected patients, and 50.8 +/- 2.8 against 23.0 +/- 3.2 for mononuclear cells from normal and infected patients, respectively. The killing effect of granulocytes dropped from 48.7 +/- 2.8 to 22.1 +/- 2.2 when autologous mononuclear cells from chronically infected patients were added to the system. Similar inhibitory effect of granulocyte function was obtained when these cells were incubated with normal mononuclear cells precultured with concanavalin A. Extracts prepared from mononuclear cells obtained from infected patients had the same inhibitory effect of intact cells on the complement-dependent granulocyte cytotoxicity.

Inbred mouse strains vary widely in their susceptibility to the induction of tolerance following oral (intragastric) administration of ovalbumin. Marked differences were found between strains that form a congenic pair differing at the H-2 complex: C3H/HeJ (H-2k) and C3H.SW (H-2b)-which were very susceptible and resistant to tolerance induction, respectively. In contrast, no significant differences were found between A/J (H-2a) and A.BY (H-2b) congenics, which were both susceptible, nor among C57BL/10J congenics, which were uniformly resistant to tolerance induction. We conclude that H-2-linked genes determine tolerance susceptibility in conjunction with background genes.

1. We show that mouse strains differ widely in susceptibility to tolerance induction and/or immunization (priming) following contact of protein antigens (ovalbumin, human or bovine gamma globulins) with different mucosal surfaces. 2. When compared to a control group pretreated with saline, mice pretreated by the oral (intragastric) route with antigen became significantly less responsive to subsequent parenteral immunization (i.e., tolerant). This was observed in most, but not all, antigen/strain combinations. 3. Similar, although less prominent changes were induced by pretreatments with antigen by the ocular (conjunctival) route. 4. No significant effects were observed following pretreatments by the nasal, vaginal or rectal routes. 5. Genes present in strains selected for multispecific "high" or "low" responsiveness are included among those involved in tolerance induction following mucosal contacts with protein antigens.