Effects of population mobility on the COVID-19 spread in Brazil

This article proposes a study of the SARS-CoV-2 virus spread and the efficacy of public policies in Brazil. Using both aggregated (from large Internet companies) and fine-grained (from Departments of Motor Vehicles) mobility data sources, our work sheds light on the effect of mobility on the pandemic situation in the Brazilian territory. Our main contribution is to show how mobility data, particularly fine-grained ones, can offer valuable insights into virus propagation. For this, we propose a modification in the SENUR model to add mobility information, evaluating different data availability scenarios (different information granularities), and finally, we carry out simulations to evaluate possible public policies. In particular, we conduct a case study that shows, through simulations of hypothetical scenarios, that the contagion curve in several Brazilian cities could have been milder if the government had imposed mobility restrictions soon after reporting the first case. Our results also show that if the government had not taken any action and the only safety measure taken was the population's voluntary isolation (out of fear), the time until the contagion peak for the first wave would have been postponed, but its value would more than double.

Are coping styles consistent in the teleost fish Sparus aurata through sexual maturation and sex reversal?

Individual differences in behaviour and physiological responses to stress are associated with evolutionary adaptive variation and thus raw material for evolution. In farmed animals, the interest in consistent trait associations, i.e. coping styles, has increased dramatically over the last years. However, one of limitations of the available knowledge, regarding the temporal consistency, is that it refers always to short-term consistency (usually few weeks). The present study used an escape response during a net restraining test, previously shown to be an indicative of coping styles in seabream, to investigate long-term consistency of coping styles both over time and during different life history stages. Results showed both short-term (14 days) consistency and long-term (8 months) consistency of escape response. However, we did not found consistency in the same behaviour after sexual maturation when the restraining test was repeated 16, 22 and 23 months after the first test was performed. In conclusion, this study showed consistent behaviour traits in seabream when juveniles, and a loss of this behavioural traits when adults. Therefore, these results underline that adding a life story approach to data interpretation as an essential step forward towards coping styles foreground. Furthermore, a fine-tuning of aquaculture rearing strategies to adapt to different coping strategies may need to be adjusted differently at early stages of development and adults to improve the welfare of farmed fish.

The spectrum and outcome of pregnant trauma patients in a metropolitan trauma service in South Africa

INTRODUCTION

Pregnant patients involved in trauma pose unique diagnostic and treatment challenges as the physiological and anatomical changes associated with pregnancy, and the need to preserve foetal well-being, result in a number of nuances in the standard resuscitation algorithms. This clinical audit within a busy developing world trauma service describes the spectrum and outcome of pregnant trauma patients.

METHODS

All pregnant patients presenting to the Pietermaritzburg Metropolitan Hospital Complex following trauma were included in the study. Data were retrieved from the trauma registry and analyzed using descriptive statistics on a spreadsheet. The study ran from the 1st of July 2011 to the 31st of December 2013.

RESULTS

During the study period, 1075 female trauma patients were admitted, with a 4% incidence of pregnant patients (42/1075). The mean age of the patients in the study was 24.9 years with an average age of gestation of 21.4 weeks. Blunt trauma accounted for the majority of injuries (57%). Trauma was by way of intentional assault in 52% of the cases. Of the cases of assault, 81% of the time, the assailant was known to the victim and in the majority of cases (55%) the assailant was the patient's intimate partner. Polytrauma predominated as the most common pattern of injury. Foetal death occurred in more than a third of cases (15/42). In 90% of the patients with an Injury Severity Score greater than fifteen, there was foetal death. Eighty-six percent (6/7) of the patients who required surgery had an unfavourable foetal outcome. In 73% of the cases of foetal death, the pregnancies were less than 28 weeks gestation.

CONCLUSION

In an environment with high rates of interpersonal violence, trauma in pregnancy is not an uncommon occurrence. It is most commonly due to assault and the assailant is known to the victim in the majority of cases. Blunt trauma still predominates in this setting but there is a high incidence of penetrating trauma. Foetal mortality in this group is high and reflects the severity of the trauma experienced.

Two- and three-dimensional profilometer assessments to determine titanium roughness

In this study, a comparative topography analysis of titanium (Ti) surfaces was performed using two- (2D) and three-dimensional (3D) profilometers. Ti samples were either only sandblasted (SB) using Al(2)O(3) particles or were SB and received an additional chemical treatment using a solution of 4% HF (SLA). Samples with no treatment were used as a control group (C). Therefore, three different surfaces were evaluated: SB, SLA and C. The Ti surface topographies were evaluated by scanning electron microscopy. An Ra roughness measurement was performed on each Ti sample by 2D and 3D profilometers. Surface roughness was also characterized using amplitude, spatial and hybrid 3D parameters. 2D and 3D profilometer analyses produced very close results. Mean Ra values range from 0.19 to 0.25 (C, p<0.05), 0.84 to 0.99 (SLA, p<0.05) and 0.98 to 1 microm (SB, p>0.05). The statistically different Ra values depending on the surface studied may be explained by methodological and technical differences. Also, 3D profilometer seems to be the more appropriate analytical method for measuring the roughness of Ti surfaces because it also describes surface organization.

Bilateral nerve-sparing extraperitoneal visual laser ablation radical prostatectomy: potency rates after 1 year follow up

PURPOSE

Wide variations exist in the methods for reporting potency following radical prostatectomy. In this group we used a validated questionnaires pre and post operatively to access relative return to normal sexual function after bilateral nerve-sparing visual laser ablation radical prostatectomy (VLAP).

MATERIALS AND METHODS

One hundred and twenty four patients with ages ranging from 45 to 70 years old were evaluated in the period between January 2004 and March 2007. Sexual function was evaluated using the IIEF questionnaire pre operatively and 3, 6, 9, and 12 months after the surgery. All the procedures were performed by the same surgeon using bilateral nerve-sparing technique. No thermal energy devices were utilized for coagulation and clipping was minimal in order to better preserve the neurovascular bundles.

RESULTS

Preoperatively one hundred and four patients had no sexual dysfunction and a 28.2 average according to IIEF score. Thirteen patients were classified in the mild category with 21.8 average score. Five patients were in the mild to moderate group and scored an average of 17 points in the IIEF. Two patients were classified moderate group and scored 10. None were classified in the severe group preoperatively. After 1 year 85 patients were classified in the no dysfunction group and scored an average of 25.3. Eleven patients were in the mild erectile dysfunction group scored 16.9. Sixteen patients in the mild to moderate group scored 12. Eight patients in the moderate group scored seven. Four patients migrated to the severe dysfunction group, scoring two points. 29% of the patients that have had sexual intercourse used medication to improve or obtain erection.

CONCLUSION

Careful preservation of the neurovascular bundles provides good potency recovery rates, but no final conclusion should be established before one year of follow-up.

NK1.1 Cells Downregulate Murine Endotoxin-Induced Uveitis Following Intraocular Administration of Interleukin-12

To evaluate the role of IFN-gamma (interferon gamma) in IL-12- (interleukin-12)-induced inhibition of the inflammatory response in the eye during endotoxin-induced uveitis (EIU). C57BL/6 wild type mice and IFN-gamma-deficient (GKO) mice were injected with 250 microg of Salmonella typhymurium endotoxin as a model for EIU. Animals were then injected intraocularly with 100 ng of rIL-12 or the equivalent volume of Phosphate-buffer saline (PBS). Histopathologic grading of disease was performed 12, 36 and 72 h after endotoxin injection. Chemokine mRNA expression in the eye was evaluated by reverse transcriptase-polymerase chain reaction. Depletion of NK1.1+ cells in vivo was performed using a PK136 antibody. Depletion of IFN-gamma was performed using the R4-6A2 antibody. C57BL/6 mice treated with rIL-12 intraocularly were protected from the development of EIU. Neutralization of IFN-gamma with a monoclonal antibody abrogated such protection. The IL-12 protective effects were lost in NK1.1-depleted mice. Intraocular IL-12 decreased the expression of keratinocyte-derived chemokines (KC) gene but had no effect on macrophage inflammatory protein (MIP-2) gene. The protective effect of IL-12 during EIU occurs through production of IFN-gamma by NK1.1+ cells. IL-12-induced higher levels of IFN-gamma are also correlated with lower expression of the chemokine KC, resulting in diminished attraction of neutrophils to the inflammatory site.

The effect of extracellular matrix molecules on mouse preimplantation embryo development in vitro

The extracellular matrix (ECM) molecules, laminin (LN), chondroitin sulfate (CS), fibronectin (FN), hyaluronic acid (HA), mucin (MUC) and heparan sulfate proteoglycan (HS), were investigated as supplements to culture medium to improve the in vitro development of mouse 1-cell zygotes to blastocysts. Development was also compared with that in medium supplemented with bovine serum albumin (BSA) to determine the potential for ECM molecules as suitable alternatives to serum albumin in culture medium. Supplementation of sequential culture media with LN at all concentrations examined failed to result in more than 70% of zygotes developing to blastocysts; therefore, LN was considered unsuitable as a replacement for BSA and was not examined further. The optimal concentration of the remaining ECM molecules was used to supplement sequential culture media and the effect on blastocyst quality was assessed by determining the differential cell numbers of blastocysts grown in BSA-supplemented medium. Development to blastocyst was similar, regardless of the macromolecule used. The number of inner cell mass cells was significantly higher in HS-supplemented medium compared with controls. Trophectoderm cell numbers were similar to control values for all ECM molecules examined except CS for which there were fewer trophectoderm cells. It is concluded that ECM molecules, FN, HA, MUC and HS may be used as substitutes for serum protein supplementation of culture media EG0/G2 for mouse preimplantation embryo development. Heparan sulfate proteoglycan increases inner cell mass numbers and this may be due to interactions with the growth factors fibroblast growth factor 4 (FGF-4) and granulocyte-macrophage colony-stimulating factor.

Dentin-induced in vivo inflammatory response and in vitro activation of murine macrophages

The activation of inflammatory cells and consequent release of mediators play an important role in the resorption of mineralized tissues. In the present study, we examined the ability of dentin extracts to induce inflammatory cell recruitment and activation. We showed here that dentin extracts triggered an intense cell migration and progressive cell maturation, in a time- and dose-dependent manner. Expression of interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), nitric oxide (NO), and hydrogen peroxide (H(2)O(2)) was also up-regulated by dentin extracts. These results show that inflammatory events can be elicited in response to dentin, which may suggest a possible involvement of dentin molecules in the inflammatory events, coupled with their release at the root resorption sites.

Involvement of prostaglandins in the immunosuppression occurring during experimental infection by Paracoccidioides brasiliensis

We investigated whether PGE2 mediates the immunosuppression observed during Paracoccidioides brasilensis infection. Con-A-stimulated splenocytes, isolated from mice on days 15 and 60 of infection, release high amounts of PGE2, this release was inhibited by the treatment of animals with indomethacin, sodium salicylate or meloxicam. The treatment of the animals with salicylate or meloxicam, but not indomethacin, enhanced the release of IL-2 by splenocytes from animals on day 15, but not on day 60 of infection. Furthermore, we demonstrated that the productions of TNF-alpha, IFN-gamma, IL-4, and IL-10 by Con-A-stimulated splenocytes from mice at 15 days of infection were inhibited by treatment with salicylate or meloxicam. Indomethacin inhibited only TNF-alpha and IFN-gamma production. The three treatments caused reduction of granuloma areas in the liver and lungs of infected mice. In conclusion, results suggest that the PGE2 released by COX-2 mediates the immunosuppression early on (day 15), but not during the later phase (60 days) of P. brasiliensis infection by a mechanism dependent upon IL-4 and IL-10.

Sex ratio and birth weights of infants born as a result of blastocyst transfers compared with early cleavage stage embryo transfers

OBJECTIVE

To analyze the birth weights and sex ratio of infants born as a result of blastocyst transfer and compare them with data resulting from the transfer of early-cleavage stage embryos.

DESIGN

Retrospective analysis.

SETTING

Monash IVF (private in vitro fertilization clinic).

PATIENTS(S)

One hundred twenty-five infertile patients who became pregnant after IVF procedures involving blastocyst transfer.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Sex ratio and birth weights of infants born after blastocyst transfer.

RESULT(S)

The sex ratio of 129.6 for infants born after blastocyst transfer was not significantly different from the sex ratio calculated from data compiled by NPSU for births resulting from early cleavage stage embryo transfers at Monash IVF (100.6) and all other assisted conception units in Australia and New Zealand (97.9). No differences were observed in the combined mean birth weight of male and female infants born as a result of blastocyst transfers and early-cleavage stage embryo transfers.

CONCLUSION(S)

There is no evidence of abnormal fetal growth or a shift in the sex ratio for infants born as a result of blastocyst transfer when compared with the case of births resulting from early cleavage stage embryo transfers within our unit or all other assisted conception units in Australia and New Zealand.

The use of preserved equine renal capsule to repair lamellar corneal lesions in normal dogs

The purpose of this study was to evaluate the use of equine renal capsule preserved in 98% glycerine to repair lamellar corneal lesions in normal dogs. For this purpose, 12 dogs, divided into six groups (n = 2), were used to evaluate the 1st to 7th day, 15th day and 30th to 60th postoperative day. In order to perform the histologic study, the clinical procedures were analyzed, while the recipient's corneas were collected. The photophobia and blepharospasm also were more intense in the 1st to 7th postoperative day, and regressed in the 15th postoperative day. Therefore, the edema and the vascular events were both more frequent in the intermediary phases and regressed in the late periods. On the other hand, the morphological evaluation demonstrated an inflamatory exudate, also in the intermediary and late periods. These results suggested that the equine renal preserved capsule could be a useful alternative tissue to repair lamellar corneal lesions in dogs.

Impact of nutritional status on outcomes after liver transplantation

BACKGROUND

Poor preoperative nutritional status has been reported to be associated with adverse outcomes after liver transplantation. Published data are, however, conflicting, with methods of preoperative nutritional assessment and postoperative outcomes varying between studies.

METHODS

We prospectively studied the predictive value of preoperative nutritional status for adverse outcomes after liver transplantation. Assessment of preoperative nutritional status included: body cell mass determination, subjective global assessment, anthropometry, handgrip dynamometry, biochemical and amino acid profile, Child's score, and dual-energy x-ray absorptiometry. Death, intensive care unit (ICU) length of stay > or =4 days, hospital length of stay > or =15 days, blood usage > or =36 U of blood products, infection, rejection, and global resource utilization (an index of cost) greater than the median were considered poor outcomes.

RESULTS

Fifty-three patients were studied. Longer ICU stay was associated with lower handgrip strength (P<0.01) and lower aromatic amino acid levels (P<0.01). Longer total hospital stay and the development of infections were associated with lower branched chain amino acid levels (P<0.01 and <0.001, respectively). Acute cellular rejection was associated with lower total body fat (P<0.001) and higher triglyceride levels (P<0.02). Neither death nor higher global resource utilization was associated with any preoperative nutritional parameter.

CONCLUSIONS

Lower preoperative handgrip strength and branched chain amino acid levels are associated with longer ICU stays and increased likelihood of posttransplant infections. In our program, in which nutritional support was provided to potential recipients exhibiting malnourishment, none of the measured nutritional parameters were associated with mortality or greater global resource utilization.

Lucio's phenomenon: clinical and therapeutic aspects

We report four cases of necrotizing reactions of the Lucio's phenomenon type, an entity rarely observed in Brazil despite the high prevalence of leprosy. Clinical, histopathological and therapeutic aspects are described and compared to those reported in the literature for cases classified as diffuse, non-nodular lepromatous leprosy with Lucio's phenomenon.

Impact of nutritional status on outcomes after liver transplantation

BACKGROUND

Poor preoperative nutritional status has been reported to be associated with adverse outcomes after liver transplantation. Published data are, however, conflicting, with methods of preoperative nutritional assessment and postoperative outcomes varying between studies.

METHODS

We prospectively studied the predictive value of preoperative nutritional status for adverse outcomes after liver transplantation. Assessment of preoperative nutritional status included: body cell mass determination, subjective global assessment, anthropometry, handgrip dynamometry, biochemical and amino acid profile, Child's score, and dual-energy x-ray absorptiometry. Death, intensive care unit (ICU) length of stay > or =4 days, hospital length of stay > or =15 days, blood usage > or =36 U of blood products, infection, rejection, and global resource utilization (an index of cost) greater than the median were considered poor outcomes.

RESULTS

Fifty-three patients were studied. Longer ICU stay was associated with lower handgrip strength (P<0.01) and lower aromatic amino acid levels (P<0.01). Longer total hospital stay and the development of infections were associated with lower branched chain amino acid levels (P<0.01 and <0.001, respectively). Acute cellular rejection was associated with lower total body fat (P<0.001) and higher triglyceride levels (P<0.02). Neither death nor higher global resource utilization was associated with any preoperative nutritional parameter.

CONCLUSIONS

Lower preoperative handgrip strength and branched chain amino acid levels are associated with longer ICU stays and increased likelihood of posttransplant infections. In our program, in which nutritional support was provided to potential recipients exhibiting malnourishment, none of the measured nutritional parameters were associated with mortality or greater global resource utilization.

Amniotic membrane transplantation for acute chemical or thermal burns

PURPOSE

To determine whether preserved human amniotic membrane (AM) can be used to treat ocular burns in the acute stage.

DESIGN

Prospective, noncomparative, interventional case series.

PARTICIPANTS

Thirteen eyes from 11 patients with acute burns, 10 eyes with chemical burns and 3 with thermal burns of grades II-III (7 eyes) and grade IV (6 eyes), treated at 7 different facilities.

METHODS

Patients received amniotic membrane transplantation (AMT) within 2 weeks after the injury.

MAIN OUTCOME MEASURES

Integrity of ocular surface epithelium and visual acuity during 9 months of follow-up.

RESULTS

Ten patients were male and one patient was female; most were young (38.2 +/- 10.6 years). For a follow-up of 8.8 + 4.7 months, 11 of 13 eyes (84.63%) showed epithelialization within 2 to 5 weeks (23.7 +/- 9.8 days), and final visual acuity improved > or = 6 lines (6 eyes), 4 to 5 lines (2 eyes), and 1 to 3 lines (2 eyes); only one eye experienced a symblepharon. Eyes with burns of grade II to III showed more visual improvement (7.3 +/- 3 lines) than those with burns of grade IV (2.3 +/- 3.0 lines; P < 0.05, unpaired t test). In the group with grade II or III burns, none had limbal stem cell deficiency. All eyes in the group with grade IV burns did experience limbal stem cell deficiency.

CONCLUSIONS

Amniotic membrane transplantation is effective in promoting re-epithelialization and reducing inflammation, thus preventing scarring sequelae in the late stage. In mild to moderate burns, AMT alone rapidly restores both corneal and conjunctival surfaces. In severe burns, however, it restores the conjunctival ocular surface without debilitating symblepharon and reduces limbal stromal inflammation, but does not prevent limbal stem cell deficiency, which requires further limbal stem cell transplantation. These results underscore the importance of immediate intervention in the acute stage of eyes with severely damaged ocular surface. Further prospective randomized studies including a control group are required to determine the effectiveness of AMT in acute chemical and thermal burns of the eye.

Macrophage expression of class II major histocompatibility complex gene products in Paracoccidioides brasiliensis-infected mice

C57B1/6 isogenic mice infected with Paracoccidioides brasiliensis strains showed a disruption in the expression of Ia antigen. Expression slowly decreased during the course of the infection with a slight variation dependent on the route of inoculation and the fungal strain used, but production of interferon-gamma and tumor necrosis factor-alpha were observed. Suppression of Ia antigen expression and depression of the immunoproliferative responses of spleen cells were strongly correlated with nitric oxide levels. These parameters were inhibited when the animals were treated with nitro-L-arginine, which resulted in inhibition the activation of nitric oxide (NO) production. Analysis of the data showed that changes in the expression of the Ia antigen occur in P. brasiliensis infection and are strongly correlated with NO levels. These phenomena may be interrelated and reflect macrophage activation that contributes to the control of the disease and to the immunosuppression observed during the course of the infection.

Connective tissue responses to calcium hydroxide-based root canal medicaments

AIM

The objective of the present study was to evaluate the tissue inflammatory response induced by calcium hydroxide pastes, with or without paramonochlorophenol and camphor.

METHODOLOGY

Isogenic BALB/c mice were inoculated into the subcutaneous tissue with either 0.1 mL of a suspension of Calen, Calen with camphorated paramonochlorophenol, Calen with paramonochlorophenol, Calasept paste or phosphate-buffered saline (control). After 6, 12 and 24 h and 2, 3, 5, 7 and 15 days, three animals in each group were sacrificed and the excised lesions processed for histopathological evaluation of the inflammatory response. Events monitored and graded included the assessment of vascular congestion, oedema, haemorrhage, inflammatory infiltrate, necrosis and tissue repair.

RESULTS

The pastes induced an inflammatory response at every observation period, although the intensity, duration and extension of inflammation varied. Calen paste always produced an initial short-term inflammatory response whilst the other pastes produced extended reactions. All pastes allowed repair to take place by the end of the experimental period, although the speed of this process varied between the materials. Calen presented the best biocompatibility; the phenolic compound caused greater tissue response, which was even more severe in the absence of camphor. Calasept paste was damaging and the repair process slower.

CONCLUSIONS

All calcium hydroxide formulations caused an inflammatory response. The severity and longevity of the responses varied between pastes as a result of the various antiseptic agents. Although irritating, repair was apparent with all formulations.

Hemangioendothelioma of bone in a patient with a constitutional supernumerary marker

A 13-year old girl was diagnosed as having a bone hemangioendothelioma. Cytogenetic studies identified the presence of a small supernumerary marker chromosome in this patient. Classical cytogenetic methods using G-, C-, Ag-NOR-banding were supplemented by spectral karyotyping (SKY) and fluorescence in situ hybridization to reveal a karyotype 47,XX,+mar.ish der(22)(D22S543+) karyotype in cells derived from the tumor and lymphocytes. These findings suggest that the supernumerary marker chromosome originated from the proximal centromeric region of chromosome 22, and that trisomy of the region 22q11 was not associated with adverse phenotypic effects, but that the presence of trisomy 22q11 may be related to the development of this tumor.

Plasma-kallikrein clearance during liver regeneration after partial hepatectomy in the rat

AIMS/BACKGROUND

The liver clears circulating plasma-kallikrein through a receptor-mediated endocytosis process: an initial fast phase is followed by a slow exponential phase.

METHODS

To determine whether the clearance rate of plasma-kallikrein is affected during liver regeneration, we perfused isolated rat livers with rat plasma-kallikrein (rPK) at 0, 1, 2, 3 and 7 days after partial hepatectomy or sham operation.

RESULTS

Liver regeneration was followed by the expression of the proliferating-cell nuclear antigen (PCNA) labeling index. The serum concentration of alpha2-macroglobulin, an acute phase protein in rats, was measured. At day 1, the fast phase of rPK clearance rate increased in hepatectomized rats when compared with day 0 (4.9+/-0.4 and 3.7+/-0.4 mU/g liver min, p<0.05). However, at day 2, the rPK fast phase clearance rate dropped significantly (2.6+/-0.2, p<0.05), when compared with day 1. No difference was found among the sham groups at different days of hepatectomy. These changes seem to be independent of the acute phase reaction. The regenerative liver weight increased continuously during the observation period. PCNA expression increased significantly after hepatectomy, with maximal PCNA-labeling indices at days 1 and 2, declining thereafter.

CONCLUSION

The rPK fast phase clearance rate changes during liver regeneration, with a zenith occurring when PCNA labeling index is maximal (day 1) and a nadir occurring at the mitotic phase (day 2).

Treatment of Paracoccidioides brasiliensis-infected mice with a nitric oxide inhibitor prevents the failure of cell-mediated immune response

The activation of the nitric oxide (NO) production system and its involvement in the control of the lung fungal burden and in immunosuppression mechanisms were studied during the course of Paracoccidioides brasiliensis-infected mice. Mice that had been infected with the fungus were treated daily with a specific inhibitor of NO synthesis, N omega-nitro-L-arginine, or with buffered saline (control); NO production was assessed on the basis of spontaneous NO2- production by bronchoalveolar and peritoneal macrophages (Mphi) and of serum NO3- levels. The infection coursed with an elevation of NO3- levels. The Mphi produced NO2- and released TNF-alpha only after stimulation with LPS. In addition, the immunoproliferative responses of spleen cells that had been stimulated with the fungus Ag or with Con A were depressed. An examination of the lungs of infected animals showed a progressive increase in the size of the lesions. Treatment of the animals, which resulted in an inhibition of NO2- production by Mphi and a reduction of serum NO3- levels, caused the spontaneous release of TNF-alpha from infected animals and prevented the failure of the lymphoproliferative capacity of spleen cells. Furthermore, the treatment resulted in less pulmonary damage despite the fact that the lung fungal burden increased. It was also demonstrated that the NO donors S-nitroso-acetyl penicillamine and 3-morpholino-sydnonimine-hydrochloride were able to inhibit the growth of P. brasiliensis in vitro. These results suggest that although NO is important for the killing of the fungi, the activation of NO production in P. brasiliensis infection contributes to the occurrence of the immunosuppression observed during the course of the infection.

Microbicidal activity of eosinophils is associated with activation of the arginine-NO pathway

In order to investigate the ability of rat peritoneal eosinophils to produce nitric oxide (NO) induced by cytokines in vitro, these cells were activated with several cytokines (IL-5, IL-8, Rantes, TNF-alpha, IFN-gamma) in association or not with LPS. Under these conditions, we were able to detect nitrite in the incubation medium when the eosinophils were stimulated with IFN-gamma or IL-8 in the presence of LPS. LPS alone also induced nitrite production. Significant levels of nitrite in the medium were already present after 12 h of stimulation and increased steadily within the next 48 h. Regarding NO synthase, its highest activity was achieved at 12 h after IFN-gamma/LPS stimulation. After this peak, the enzymatic activity reduced gradually to control levels 48 h after the stimulation. The simultaneous addition of the NO synthase inhibitor L-NIO (100 microM) to the eosinophil suspension blocked nitrite production and NO synthase activity. On the other hand, neither IL-5, Rantes nor TNF-alpha were able to induce the release of nitrite in the presence or absence of LPS. To evaluate the microbicidal effect of these cells against the Leishmania parasite, eosinophils were infected with Leishmania major. It was observed that these cells were able to produce nitrite and to kill the parasite after activation with LPS/IFN-gamma. Moreover, L-NIO blocked this leishmanicidal activity and the nitrite production. Our results suggest that activated eosinophils release NO which is involved in their microbicidal activity against Leishmania major.

Cellular requirements for immunomodulatory effects caused by cell wall components of Paracoccidioides brasiliensis on antibody production

In a previous study, we reported an increase in the number of immunoglobulin-secreting cells and the augmentation of antibody production (IgM and IgG3) against unrelated antigens (sheep erythrocytes or bovine serum albumin (BSA)) in mice infected with the fungus Paracoccidioides brasiliensis as well as in mice inoculated with its cell wall preparation (CW). The immunomodulatory effect of the live fungus and CW preparation was dose-dependent and mainly restricted to the i.p. inoculation simultaneously to the BSA challenge by the i.v. route. In the present study, we investigated the active component of CW preparation upon the phenotype and also the degree of activation of possible target peritoneal cells involved in those phenomena. An insoluble polysaccharide fraction (F1 fraction) mainly composed of beta-glucan and chitin, and the purified beta-glucan (BGPb) behaved as CW in the augmentation of early antibody production. The peritoneal mononuclear inflammatory cells induced by CW, F1 fraction and BGPb were highly positive to alpha-naphthyl esterase staining; released low H2O2; expressed high levels of MHC-Ia(d) molecules and produced inflammatory cytokines such as tumour necrosis factor-alpha (TNF-alpha) and IL-6. Phenotypic analysis by flow cytometry and immunohistochemical techniques of the inflammatory cells responding to F1 fraction showed a prevalence of (CD11b/CD18, Mac-1)+ peritoneal macrophages. In addition, s.c. inoculation of F1 fraction resulted in the formation of nodular, localized and not progressive granulomatous lesions with an accumulation of (CD11b/C18)+ macrophages. Adoptive transferred Mac-1 macrophages to immunized syngeneic recipient mice were able to cause an increase in anti-BSA antibody production. These results suggest that inflammatory (CD11b/CD18)+ macrophages may be related to immunological disturbances, caused by cell wall components of P. brasiliensis.

Inflammatory response to calcium hydroxide based root canal sealers

This study evaluated the inflammatory response to Sealapex, CRCS, Apexit, and Sealer 26 in the subcutaneous tissue and in peritoneal cavity of Balb/c mice. The inflammatory response of subcutaneous tissue was analyzed after 2, 4, 8, and 16 days. Intense neutrophilia was seen in response to all sealers during the initial periods. Differences among them related to the presence of necrosis and the number of inflammatory cells. In the intermediate phase marked differentiation of cells of the mononucleate phagocytic system into macrophages, epithelioid cells and multinucleate giant cells were observed with Sealapex. This response was less intense with CRCS and Apexit. Tissue necrosis was observed only at tissue sealer interfaces and only during the initial period with Sealapex but was seen throughout the experiment with all other sealers. The animals were injected in the peritoneal cavity with solutions containing the sealers and five mice from each group were killed 6 and 24 h, and 5 and 15 days later. During the initial periods (6 and 24 h) there was an intense migration of polymorphonuclear leukocytes to the peritoneal cavity in response to all sealers compared to the control. This migration was more intense for Sealer 26 and Apexit. An increase in mononucleate cell number was observed after 6 and 24 h and 5 days for all sealers and no differences were observed in relation to the control after 15 days.

Detection of transforming growth factor-beta 1 in dermal lesions of different clinical forms of leprosy

Immunohistochemical studies were performed to determine the presence and distribution of polypeptide transforming growth factor (TGF)-beta 1, a cytokine with macrophage-suppressing activity, in skin biopsies from 41 patients with different clinical forms of leprosy. We used an anti-TGF-beta 1 polyclonal antibody and the avidinbiotin-peroxidase (ABC complex) method. The results demonstrated that the lesions of the lepromatous and borderline lepromatous forms presented intense cytoplasm staining for TGF-beta 1 in the cells of the dermal infiltrate. A reaction of moderate intensity was observed in the cells of granulomas from borderline borderline cases, whereas no detectable immunoreaction was observed in granuloma cells from the tuberculoid and borderline tuberculoid forms. Considering that in the lepromatous leprosy form Mycobacterium leprae multiplies in the cytoplasm of macrophages and the lesions are diffuse and consist of poorly differentiated young macrophages, we believe that these alternations may be explained at least in part by the presence of TGF-beta 1 in the dermal infiltrate. Production of the cytokine may be induced by the presence of the bacillus itself and of its constituents, causing a mechanism of parasite evasion. Similarly, the absence of TGF-beta 1 in tuberculoid leprosy, which progresses with a specific immune response to M. leprae, may explain the intense differentiation of macrophage cells with the formation of well defined epithelioid granulomas capable of eliminating most of the bacilli.

[Delayed hypersensitivity to Trypanosoma cruzi antigen. II--Use of the skin test with T12E antigen for the diagnosis of Chagas disease]

Delayed-type skin reactivity against a Trypanosoma cruzi antigen was elicited in 35.7 percent of the individuals living in the country of Mambaí, state of Goiás, Brazil. The specificity of this skin reaction was shown in 93 out of 94 (98.7%) chagasic patients, in whom the parasitemias were detected by xenodiagnosis. In these patients, however, the hemagglutination, immunofluorescence and complement fixation assays were positive in respectively, 100, 97.8 and 80.6 per cent. The relationship between the combined positive results by hemagglutination and immunofluorescence with that obtained with skin testings was 0.897, in the overall population in this study. The quantity of 50 micrograms of protein in 100 microliters of the T12E antigen did not produce undesired effects, and did not shift the immunologic assays, when healthy volunteers were skin tested five times within 15-day intervals. Also, the potency of this antigen remained unaltered after 24 months at -10 degrees C.

Time-course of hypothalamic CRH and pituitary ACTH contents, and pituitary responsiveness to CRH stimulation after bilateral adrenalectomy

The pituitary ACTH and hypothalamic CRH alterations at different periods after adrenalectomy (ADX) or Sham ADX were studied by measurement of ACTH and CRH contents by radioimmunoassay (RIA) in rats. We also studied the corticotroph alterations by immunohistochemistry and the in vitro pituitary responsiveness to CRH. Plasma ACTH presented a triphasic response after ADX. Anterior pituitary (AP) ACTH content decreased 3 h and 1 day after surgery, then rose over this period. Immunohistochemistry demonstrated an initial degranulation of the corticotrophs with a progressive increase in cells immunostained for ACTH and a positive correlation (r = 0.88) with AP ACTH content measured by RIA. Hypothalamic CRH content decreased after ADX, but returned to sham value 3 weeks later. Basal ACTH secretion in incubation medium was correlated with the AP ACTH content observed in vivo. The pituitary responsiveness to CRH was not the same at all times after ADX. It was absent 1 day after, presented an increase of 51%, 117% and 26% when compared with the basal ACTH output 3 h, 3 and 14 days after ADX, respectively. Our data suggest that after ADX the corticotroph undergoes a transitory decrease in ability to secrete ACTH after store depletion. During a later phase, however, there is a relative hyporesponsiveness of the corticotroph to CRH stimulation. These data indicate that CRH may be acting on a down-regulated pituitary or more additional factors play a role in the sensitization of the pituitary after ADX.

[Hemodynamic effects of propafenone in dogs anesthesized with halothane or isoflurane]

OBJECTIVE

Several studies suggest that anaesthetic drugs influence the haemodynamic effects of the antiarrhythmic drugs. The aim of this study was to compare the haemodynamic effects of a standard dose of propafenone (1.5 mg/kg) on dogs anaesthetized with halothane or with isoflurane.

DESIGN

Randomized laboratory animal study.

MATERIAL AND METHODS

Six dogs were anaesthetized with 1% of halothane-Group I, and six dogs with an equianaesthetic dosage of isoflurane (1.5%)-Group II. Dogs breathed in spontaneous ventilation. Haemodynamic monitoring was performed with a femural arterial catheter and a flow-directed pulmonary artery catheter and cardiac output was measured by thermodilution. After a haemodynamic assessment considered as initial a bolus of 1.5 mg/kg of propafenone was given during a period of 30 seconds and similar assessments were made 5, 15, 30 and 60 minutes after.

RESULTS

Before propafenone, heart rate was significantly higher in Group II-isoflurane (p < 0.05). After propafenone we found: In both Groups, a decrease in the cardiac output (p < 0.05) with the mean arterial pressure maintained; in Group I (halothane) a decrease in the stroke volume (p < 0.05) which was not found in Group II (p = ns); In Group II (isoflurane) a decrease in heart rate (p < 0.05) not found in Group I (p = ns). All the changes were higher at the 5th minute values. 30th minute and 60th minute values were not significantly different from initial values.

CONCLUSION

In dogs anaesthetized with halothane 1.2 MAC a reduction in the stroke volume, resulting in a cardiac output decrease, was observed, suggesting that propafenone increases the negative inotropic action of halothane. In dogs anaesthetized with isoflurane 1.2 MAC the decrease in cardiac output was similar to the decrease in heart rate, and therefore no reduction in the stroke volume was observed. The decrease in the heart rate found in this group but not in the halothane group was probably related with the beta-blocker action of the propafenone. Looking to the systemic vascular resistances, our study suggested that propafenone didn't have any vasodilator effect during halogenated anaesthesia.

Involvement of cell wall glucans in the genesis and persistence of the inflammatory reaction caused by the fungus Paracoccidioides brasiliensis

The role of cell wall polysaccharides in leucocyte recruitment and granuloma formation in paracoccidioidomycosis was investigated. The inflammatory cells recruitment to the peritoneal cavity in rats inoculated with cell wall fraction (CW-265 or F1-265) from an avirulent strain of Paracoccidioides brasiliensis (Pb265), was greater than that observed for the cell wall fraction (CW-HC or F1-HC) recovered from the virulent strain (PbHC). Moreover, the inoculation of F1-HC and F1-265 into the subcutaneous layer of mice resulted in the formation of nodular and not progressive granulomatous lesions. The size and mean time of evolution of these lesions was proportional to the degree of virulence of the sample from which they were derived. Analyses showed that both F1 fractions contained beta-glucan and chitin. Only beta-glucan was able to trigger attraction and concentric organization of polymorphonuclear neutrophils and macrophages at the inflammatory foci, and the difference in the concentration of this compound in the cell walls of PbHC and Pb265 could explain the inflammatory capacity exhibited by the two strains of P. brasiliensis.

Tumour necrosis factor production in vivo and in vitro in response to Paracoccidioides brasiliensis and the cell wall fractions thereof

Tumour necrosis factor (TNF) was detected in serum from mice challenged with Paracoccidioides brasiliensis. The serum TNF levels of mice challenged with an avirulent strain were significantly higher than those of mice challenged with a virulent strain, and the same was observed for the TNF levels of mice challenged with a cell wall fraction (F1) from the two fungal strains. Fraction F1 consisted of chitin and beta-glucan; but although the chitin contents were similar for the two strains, the avirulent strain allowed a greater content of beta-glucan. The beta-glucan, purified from both strains, increased serum TNF levels in an identical dose-dependent manner, whereas purified chitin did not induce serum TNF levels. P. brasiliensis, the F1 fractions and beta-glucan induced macrophages to secrete TNF in vitro. The differences in TNF levels, induced by the different fungal strains, were correlated with the beta-glucan concentrations in the cell walls of both the avirulent and virulent strains of P. brasiliensis. These findings support a role for TNF in the pathogenicity of P. brasiliensis.

Fulminant disseminated pulmonary adiaspiromycosis in humans

A case of fulminant disseminated pulmonary adiaspiromycosis is reported. The patient, a 35-year-old black male farm worker, presented with a four-week history of generalized weakness, unproductive cough, evening fever, and a weight loss of 8 kg. He died 12 days after hospitalization of respiratory failure due to granulomatous lung disease. The clinical and radiographic findings were indistinguishable from those of miliary tuberculosis. Microscopic examination of material obtained at autopsy revealed the large fungus characteristic of adiaspiromycosis in the center of suppurative granulomas throughout the lungs. This is believed to be the first fatal case of pulmonary adiaspiromycosis reported in humans, and it may have been occupationally acquired.

Molecular mechanisms regulating the expression of class II histocompatibility molecules on macrophages. Effects of inductive and suppressive signals on gene transcription

The surface expression of class II MHC molecules (immune associated or Ia Ag) is an acquired and important property of macrophages. Recent evidence from several laboratories demonstrates that mRNA levels for class II genes reflect levels of surface expression. We have investigated the effects of agents that regulate Ia expression, either positively as IFN-gamma or negatively as bacterial LPS or maleylated proteins, on transcription of these genes. By using probes for I-A beta and I-E beta as representative class II MHC genes, we found that IFN-gamma induces transcription in murine peritoneal macrophages of I-A beta and of I-E beta as determined in nuclear run-on assays. The measured transcription peaked 6 to 10 h after administration of IFN-gamma to the macrophages. This augmented expression of transcription was markedly suppressed by administration of either LPS or maleylated protein to the macrophages. Collectively, the data indicate that regulation of transcription by either positive or negative stimuli, acting through surface receptors and binding sites, is a major mechanism for controlling the expression of class II MHC molecules in macrophages.

Molecular mechanisms regulating the expression of class II histocompatibility molecules on macrophages. Effects of inductive and suppressive signals on gene transcription

The surface expression of class II MHC molecules (immune associated or Ia Ag) is an acquired and important property of macrophages. Recent evidence from several laboratories demonstrates that mRNA levels for class II genes reflect levels of surface expression. We have investigated the effects of agents that regulate Ia expression, either positively as IFN-gamma or negatively as bacterial LPS or maleylated proteins, on transcription of these genes. By using probes for I-A beta and I-E beta as representative class II MHC genes, we found that IFN-gamma induces transcription in murine peritoneal macrophages of I-A beta and of I-E beta as determined in nuclear run-on assays. The measured transcription peaked 6 to 10 h after administration of IFN-gamma to the macrophages. This augmented expression of transcription was markedly suppressed by administration of either LPS or maleylated protein to the macrophages. Collectively, the data indicate that regulation of transcription by either positive or negative stimuli, acting through surface receptors and binding sites, is a major mechanism for controlling the expression of class II MHC molecules in macrophages.

Role of Na+/H+ exchange by interferon-gamma in enhanced expression of JE and I-A beta genes

The rapid transductional sequences initiated by interferon-gamma (IFN-gamma) on binding to its receptor regulate functional and genomic responses in many cells but are not well defined. Induction of macrophage activation is an example of such functional and genomic changes in response to IFN-gamma. Addition of IFN-gamma to murine macrophages, at activating concentrations, produced rapid (within 60 seconds) alkalinization of the cytosol and a concomitant, rapid influx of 22Na+. Amiloride inhibited the ion fluxes and the accumulation of specific messenger RNA for two genes induced by IFN-gamma (the early gene JE and the beta chain of the class II major histocompatibility complex gene I-A). The data indicate that IFN-gamma initiates rapid exchange of Na+ and H+ by means of the Na+/H+ antiporter and that these amiloride-sensitive ion fluxes are important to some of the genomic effects of IFN-gamma.

The role of fractions from Paracoccidioides brasiliensis in the genesis of inflammatory response

The influx of inflammatory cells towards the peritoneal cavity in rats inoculated intraperitoneally with subcellular preparations of the fungus Paracoccidioides brasiliensis was studied. In addition to the dead fungus, also fractions F1 of the cell wall, which mainly consisted of polysaccharides and the lipid extract, induced intense cell migration 4 hr after inoculation, with a greatly increased number of polymorphonuclear leucocytes (PMN). Study of the kinetics of cell influx showed that both fraction F1 and the lipid extract initially induced intense PMN migration between the 4th and 24th hr after inoculation of these agents, followed by migration of mononuclear cells (MN) around the 48th hr. We also observed that migration of these cells increased gradually after inoculation of growing doses of fraction F1. The present data suggest that polysaccharides and lipids isolated from P. brasiliensis may participate in the initial phase of the inflammatory response in paracoccidioidomycosis.

The evolution of experimental Trypanosoma cruzi cardiomyopathy in rabbits: further parasitological, morphological and functional studies

Young rabbits (1-2 months of age) inoculated with trypomastigote forms of the Colombia strain of Trypanosoma cruzi have been shown to develop cardiac pathological changes (together with parasitological and immunological alterations) which are very similar to those observed in the acute and chronic phases of Chagas' disease in man. The cardiac alterations in the acute phase are characterized grossly by slight cardiomegaly with dilatation of the right-sided chambers. Microscopically they are characterized by mild focal myocarditis. The chronic phase is characterized by moderate to marked cardiomegaly with hypertrophy and dilatation of both ventricular chambers. There is thinning of the apical region (apical aneurysm), particularly of the left ventricle. Focal myocarditis is seen microscopically with areas of myocytolytic necrosis, atrophic and hypertrophic myofibers, an inflammatory response predominantly composed of mononuclear cells and interstitial fibrosis. Cineventriculography in the left ventricle of rabbits during the chronic phase disclosed regional myocardial dysfunction, with typical apical systolic bulging. The pathogenesis of Chagasic cardiomyopathy is briefly discussed in the light of these findings. Our investigation has further shown that this animal model is particularly suitable for studies on on the mechanisms, pathology and treatment of Chagas' heart disease.

Chagas' disease: a clinical, parasitological, immunological, and pathological study in rabbits

Thirty-four rabbits were experimentally infected with trypomastigotes of either the Ernestina or the Albuquerque strains of Trypanosoma cruzi. These animals showed patent parasitemias, as demonstrated by xenodiagnosis, in the acute phases of the infections. Typical chagoma signs developed in two rabbits 1 week after parasite inoculation in the skin, although the acute phase of Chagas' disease in the rabbit model was usually asymptomatic. In the 6th month of infection the parasitemias became negative and the infections remained subpatent, as indicated by the persistence of positive serologic tests and of delayed-type skin reactions elicited in Chagas' rabbits against a microsomal T. cruzi antigen. This latent infection continued asymptomatically, in the absence of electrocardiographic (ECG) alterations. However, ECG changes consistent with enlargement and overload of cardiac chambers, alterations of ventricular repolarization, S-T changes and bundle-branch blocks were frequently recorded later in the chronic phase of Chagas' disease. The pathological manifestations of these ECG alterations were confirmed at the autopsy of each experimental rabbit. Congestive heart failure and pulmonary thromboemboli related to chronic myocarditis of Chagas' disease were frequent causes of death. Megacolon was seen in two rabbits inoculated with the Ernestina strain of the parasite. The relatively limited duration of detectable parasitemia even when xenodiagnosis is used, the lack of correlation between parasitemia and severity of pathological manifestations, and the fact that all infected animals showed histopathological evidence of myocarditis, destructive inflammatory lesions characterized by mononuclear infiltrates in skeletal muscles, as well as cutaneous delayed hypersensitivity to T. cruzi antigens, are notable observations in this animal model of the human disease.