Antifungal activity of terpenes isolated from the Brazilian Caatinga: a review

Terpenoids, also named terpenes or isoprenoids, are a family of natural products found in all living organisms. Many plants produce terpenoids as secondary metabolites, and these make up a large part of essential oils. One of most important characteristic is that the compounds are volatile, have odor and can be used in a variety of applications in different industrial segments and traditional medicine. Brazil has a rich and diverse flora that can be used as a source of research for obtaining new molecules. Within the Brazilian flora, it is worth mentioning the Caatinga as an exclusively Brazilian biome where plants adapt to a specific series of weather conditions and therefore become a great storehouse of the terpenoid compounds to be described herein. Fungal infections have become increasingly common, and a great demand for new agents with low toxicity and side effects has thus emerged. Scientists must search for new molecules exhibiting antifungal activity to develop new drugs. This review aims to analyze scientific data from the principal published studies describing the use of terpenes and their biological applications as antifungals.

Essential oil from leaves of Eugenia calycina Cambes: Natural larvicidal against Aedes aegypti

BACKGROUND

Eugenia calycina is an endemic species in the Brazilian savannah (the Cerrado) and it is threatened with extinction. Several species of Eugenia are used as insecticides or insect repellents. No data are available on the larvicidal activity of E. calycina. The chemical composition of the essential oil (EO) from leaves of Eugenia calycina was analyzed by gas chromatography coupled to mass spectrometry (GC-MS) and the larvicidal activity against Aedes aegypti larvae in the third stage of development was studied.

RESULTS

Oxygenated and non-oxygenated sesquiterpenes were identified, and the main compounds were bicyclogermacrene, spathulenol, and β-caryophyllene. The EO was fractionated in a chromatographic column and three compounds were isolated and identified: spathulenol, aromadendrane-4β,10α-diol, and 1β-11-dihydroxy-5-eudesmene. It is the first time that the last two compounds have been identified in E. calycina. The exposure times in the larvicidal test were 24 h and 48 h and the LC₅₀ values obtained were 199.3 and 166.4 μg mL^-1 . The cytotoxicity of the EO in mammalian cells (HeLa and Vero) was evaluated for 24 and 48 h of incubation. The cytotoxic concentrations of the EO for HeLa and Vero cells (266.8 ± 46.5 and 312.1 ± 42.5 μg mL^-1 , respectively) in 48 h of exposure were higher than the LC₅₀ , showing low cytotoxicity at the concentration exhibiting larvicidal activity, resulting in a positive selectivity index.

CONCLUSION

These results indicate that the EO of E. calycina showed high activity against the A. aegypti larvae but lower cytotoxicity to mammalian cells. The leaves of E. calycina are therefore a very promising source of natural larvicidal products. © 2020 Society of Chemical Industry.

Continuing Education in Health: interprofessional practices in the field of Collective Health

Family Health Support Centres (NASFs, in Portuguese) aim to develop interprofessional practices anchored in the assumptions of Primary Health Care, guided by the criteria of shared care specific professional interventions, management processes, interdisciplinarity, intersectoriality, Continuing Education in Health and health promotion. This health management methodology (Matrix Support) still represents a challenge to workers and managers, as it switches the logic of clinical thought from individual-centred, ambulatory and disciplinary care to collective, territory and interdisciplinary care. This study might illustrate and allow sharing of experiences about a work management format for multidisciplinary teams in Primary Health Care. A partnership between the University and the state health department was established in order to elaborate a collaborative, educational and supportive action. We formed a group of workers in the target area (24 municipalities and 18 teams) who had a focus on Continuing Education in Health using Institutional Analysis as theoretical reference. The main goal of the action was to provide spaces to share experiences and learning in the perspective of Continuing Education in Health. How does Continuing Education in Health support interprofessional practices in the field of Collective Health? Among the main results, we list: reflection about organisation practices of multiprofessional work, reflection about care practices and clinic management in the technical-assistance and pedagogic perspectives of Matrix Support; encouragement to improve the services offered in this level of care and their relationship with other points of the network. This experience showed us the importance of three main aspects: Continuing Education in Health, as a strategy of critical analysis about work and workers; the partnership and integration between teaching and service; and interprofessional formation processes (necessary to NASF and Collective Health).

Key messages

Continuing Education in Health is a strategy to deal with challenges and possibilities of interprofessional practices in the field of Collective Health. Enabling experiences and providing spaces for health professionals to share experience and learning.

Anticryptococcal activity of hexane extract from Spondias tuberosa Arruda and associated cellular events

Cryptococcosis is an opportunistic systemic mycosis whose treatment is limited to three drugs. In this work, we evaluated the antifungal activity of a hexane extract (HE) from Spondias tuberosa leaves against Cryptococcus neoformans and Cryptococcus gattii. Minimal inhibitory concentrations (MIC) were determined, and putative mechanisms were evaluated by flow cytometry. In addition, an in vivo infection assay was performed using Tenebrio molitor larvae. Treatment with HE inhibited the growth of standard and clinical isolates of C. neoformans and C. gattii (MICs ranging from 0.78 to 3.12mg/mL), significantly (P<0.05) increased mitochondrial superoxide anion levels, and induced mitochondrial membrane depolarization, loss of lysosomal membrane integrity, and phosphatidylserine externalization. The mean survival time of C. gattii-infected T. molitor larvae significantly (P<0.05) increased from 1.225 days in control to 3.067 and 3.882 days in HE-treated groups (78 and 156mg/kg, respectively). In conclusion, HE showed anticryptococcal activity, induced mitochondrial and lysosomal damage in yeast cells, and exhibited anti-infective action against C. gattii in T. molitor larvae.

Evaluation of apoptosis/necrosis and cytokine release provoked by three root canal sealers in human polymorphonuclears and monocytes

AIM

To evaluate the in vitro cytotoxicity and cytokine release of three fresh root canal sealers and to determine the type of cell death they induce.

METHODOLOGY

The sealers tested were Sealer 26 (S26), AH Plus (AHP), and Endosequence BC Sealer (END). Fresh sealers were cultivated in contact with monocytes and polymorphonuclears (PMNs) obtained from the peripheral blood of humans. Cell viability, apoptosis and necrosis were analysed at 4 h (PMNs) or 24 h (monocytes) using Annexin-V and propidium iodide in a cytometer. The supernatants were used to quantify Interleukin (IL)-4, IL-6, IL-10, IL-12 and tumour necrosis factor-α (TNF-α) in monocytes and IL-8 in PMNs by ELISA. One-way ANOVA and the Tukey post-test were used to compare data for cytotoxicity, and the multiple T-test was used to determine the differences between sealers in the release of cytokines that were statistically significant.

RESULTS

After 4 h of treatment, S26 was associated with greater cell viability than the other sealers (P < 0.05) in the PMN culture and had similar values of necrosis as END (P > 0.05). After 24 h of treatment, AHP and END had greater monocyte cell viability than S26 (P < 0.05), which had more necrosis (P < 0.05). END had the lowest levels of IL-12 compared to the other sealers (P < 0.05) and higher levels of IL-6 compared to S26 (P < 0.05). The tested sealers did not differ in the release of IL-8, IL-10, TNF-α and IL-4 (P > 0.05).

CONCLUSIONS

The effect of toxic agents released varied depending on the cell type studied. The composition of the sealers appeared to alter the form of self-regulation in the production of these cytokines by cells.

Analysis of protein profile of tomato root infected with Fusarium oxysporum f. sp lycopersici

Fusarium wilt caused by Fusarium oxysporum f. sp lycopersici (Fol) is one of the main diseases affecting tomatoes. The BHRS 2,3 genotype of tomato is, however, resistant to this disease. A proteomic approach was used to understand the defense mechanisms of this genotype using the tomato root, the first tissue that interacts with the fungus, as a target. Protein was extracted and separated by two-dimensional electrophoresis followed by staining with Coomassie brilliant blue. The proteins were identified by MALDI-TOF/TOF mass spectrometry. A total of 22 proteins were identified, 21 of which showed differential expression with 12 proteins being upregulated and nine being downregulated. Plants responded to the pathogen with increased expression of pathogenesis-related proteins. We noted the induction of proteins involved in hypersensitivity reaction and other defense mechanisms. The expression of proteins of primary metabolism related to energy production, however, decreased, as did the expression of two proteins related to defense against abiotic stress. These results demonstrate the presence of important mechanisms for defense against Fol in the tomato genotype BHRS 2,3.

Determining the genetic stability of micropropagated sugarcane using inter-simple sequence repeat markers

Sugarcane culture is an important source of income for the Brazilian economy. The aim of this study was to identify somaclonal variation in sugarcane varieties RB943365 and RB92579 arising from micropropagation using inter-simple sequence repeat (ISSR) DNA markers. The evaluated plants were generated from the in vitro propagation of shoot tips grown in MS medium supplemented with vitamins, myoinositol, glycine, and sucrose, without the use of growth regulators. Fifteen consecutive subcultures with intervals of 14 days were carried out, and DNA was extracted from young leaves obtained from each of the subcultures. The DNA was amplified with ISSR markers and separated by electrophoresis on 2% agarose gels. No evidence of polymorphism was observed in subcultures of the varieties analyzed, suggesting the absence of somaclonal variants. In this way, the ISSR marker was efficient at analyzing somaclonal variation, and in vitro propagation of sugarcane can be considered efficient for 15 consecutive subcultures of the varieties analyzed.

How to decide which infant can have robotic surgery? Just do the math

BACKGROUND

In pediatric urology, robot-assisted surgery has overcome several impediments of conventional laparoscopy. However, workspace has a major impact on surgical performance. The limited space in an infant can significantly impede the mobility of robotic instruments. There is currently no consensus on which infant can undergo robotic intervention and no parameters to help make this decision, especially for those surgeons at the start of their learning curve.

OBJECTIVE

We sought to evaluate our experience with infants to create an objective standard to determine which patients may be most suitable for robotic surgery.

STUDY DESIGN

We prospectively evaluated 45 infants (24 males, 21 females), aged 3-12 months old, who underwent a robotic intervention for either upper or lower urinary tract pathology. At the preoperative office visit the attending surgeon measured the distance between both anterior superior iliac spines (ASIS) as well as the puboxyphoid distance (PXD), regardless of whether the approach was for upper or lower tract disease. Patients' weights were also noted. During surgery, we recorded the number of robotic collisions as well as console time. All surgeries were performed utilizing the da Vinci Si Surgical System by a single surgeon.

RESULTS

There were no differences in ASIS, PXD, collisions or console time when stratified by gender, age or weight. When arranging by upper or lower tract approach, there was no difference in the number of collisions. There was a strong inverse relationship between both ASIS distance and PXD and the number of collisions. Additionally, there was a strong correlation between the number of collisions and console time (Fig. 1). Using a cutoff of 13 cm for the ASIS, there were significantly fewer collisions in the >13 cm group as compared to the ≤13 cm group. This was also true for the PXD using a cutoff of 15 cm: there were significantly fewer collisions in the >15 cm group as compared to the ≤15 cm group.

DISCUSSION

Safe proliferation of robotic technology in the infant population is, in part, dependent on careful patient selection. Our data demonstrated a reduction in instrument collisions and console time with increasing anterior superior iliac spine and puboxyphoid distances. Neither age nor weight was correlated with these measurements, the number of instrument collisions or console time. Limitations include that this is a single institution study with all infants being operated on by a single surgeon. Therefore, the findings of this study may not be generalizable to a less experienced surgeon. Yet, we believe that ASIS and PXD measurements can be used as a guide for the novice surgeon who is beginning to perform robotic-assisted surgery in infants.

CONCLUSION

We found that surgeon ability to perform robotic surgery in an infant is restricted by collisions when the infant has an ASIS measurement of 13 cm or less or a PXD of 15 cm or less. Objective assessment of anterior superior iliac spine and puboxyphoid distance can aid in selecting which infants can safely and efficiently undergo robotic intervention with a minimum of instrument collision, thereby minimizing operative time.

Genetic diversity of bat rabies viruses in Brazil

Thirty-three Brazilian bat rabies viruses (RVs) were studied by sequence analysis and were compared against sequences of bat-related RVs from other regions of the Americas. Phylogenetic analysis revealed that bat-related RVs formed several monophyletic lineages and that these were associated with bat species. Brazilian bat RVs were found to include nine major lineages, one of which grouped with RVs isolated from Lasiurus spp. from different regions of the Americas. These results suggest that there is considerable diversity among Brazilian bat RV variants and that some of these RV variants may be associated with bats from other countries.

Reiter's syndrome associated with the Acquired Immunodeficiency Syndrome: a case report

The association of Reiter's Syndrome (RS) with the Acquired Immunodeficiency Syndrome (AIDS) is seldom mentioned in the medical literature. This report illustrates this relationship in a 46 years old male patient suffering from AIDS (CD(4)(+) = 240 cells/mm(3), CD(8)(+) = 1,301 cells/mm(3) and viral load = 330,000 copies/ml), pulmonary tuberculosis (positive catarrhal bacilluscopy), and RS. The diagnosis of RS was based on the combination of dermatological and articular alterations. The patient s cutaneous lesions were characterized by exfoliation and the formation of crusts located on the face, scalp, genitals, hands, and feet; onychodystrophy with opacity; yellowish coloring; and hyperkeratosis of the nails. Articular lesions led to progressive deformity of phalangeal joints of the hands, and intensive arthralgia, mainly of the larger joints (shoulders, elbows, hips and knees). AIDS treatment was administered with anti-retroviral drugs (zidovudine and didanosine); for tuberculosis (isoniazid, rifampicine, and pyrazinamide); and (prednisone and inometacine) for the RS. The patient recovered with the improvement of articular symptoms; however, on the eighth day of treatment, the patient showed significant hemoptysis and hypovolemic shock, and died. The association of RS and HIV infection is reviewed.

Pharmacokinetics and metabolism of a RAS farnesyl transferase inhibitor in rats and dogs: in vitro-in vivo correlation

Compound I (1-(3-chlorophenyl)-4-[(1-(4-cyanobenzyl)-1H-imidazol-5-yl)methyl]piperazin-2-one) is a potent and selective inhibitor of farnesyl-protein transferase (FPTase). The pharmacokinetics and metabolism of compound I displayed species differences in rats and dogs. After oral administration, the drug was well absorbed in dogs but less so in rats. Following i.v. administration, compound I was cleared rapidly in rats in a polyphasic manner with a terminal t(1/2) of 41 min. The plasma clearance (CL(p)) and volume of distribution (V(dss)) were 41.2 ml/min/kg and 1.2 l/kg, respectively. About 1% of the dose was excreted in rat bile and urine as unchanged drug over a period of 24 h, suggesting that biotransformation is the major route of elimination of compound I. Using liquid chromatography (LC)-tandem mass spectometry, nineteen metabolites of compound I were identified in urine and bile from dogs and rats. Structures of two major metabolites were confirmed by LC-NMR. N-Dealkylation and phase II metabolism were the major metabolic pathways. Animal and human liver microsomal intrinsic clearance values were scaled to predict hepatic clearance and half-life in humans, and the predicted values were in good agreement to the in vivo data.

The first glycosides isolated from propolis: diterpene rhamnosides

Two diterpene glycosides, ent-8(17)-labden-15-O-alpha-L-rhamnoside and ent-8(17)-labden-15-O-(3'-O-acetyl)-alpha-L-rhamnoside (new natural compounds) were isolated from propolis from El Salvador. The compounds showed significant antibacterial activity and moderate toxicity to Artemia salina nauplii. These are the first glycosides reported in bee glue.

Novel cyclic peptide inhibits intercellular adhesion molecule-1-mediated cell aggregation

Leukocyte adherence mediated by intercellular adhesion molecule-1 (ICAM-1) binding to leukocyte function-associated antigen (LFA-1) is required for proper inflammatory and immune function. Inhibition of ICAM-1\LFA-1 binding using monoclonal antibodies (mAb) has been shown to be efficacious at inhibiting lymphoma metastasis as well as leukocyte emigration into tissue in a number of inflammatory diseases such as ischemia-reperfusion injury, septic shock and rheumatoid arthritis. In this report, we describe the development and characterization of a small peptide antagonist of ICAM-1-dependent cell aggregation. By using repeated selection of a cyclic nonapeptide phage display library on purified ICAM-1, we identified phage that were competitively eluted with anti-ICAM-1 mAb. The peptide sequences were determined by nucleotide sequencing, and the peptide sequence (C*LLRMRSIC*) (IP01) that occurred most frequently was chosen for further study. Phage expressing this peptide sequence specifically bound ICAM-1 over a range of 5 x 10(6) to 1 x 10(8) phage/microL. A cyclic IP01 peptide, linear IP01 peptide, a cyclic nonapeptide with a scrambled IP01 sequence, and a random, cyclic nonapeptide were synthesized. The cyclic and linear IP01 peptides were able to inhibit ICAM-1-mediated cell aggregation at a concentration of 1 mM, whereas the random and scrambled peptide sequences did not alter aggregation. Cyclic IP01 had a half-maximal inhibitory concentration of approximately 970 microM. Cyclic IP01 did not inhibit cellular aggregation that was dependent on ICAM-2 or ICAM-3. Alanine substitutions in the cyclic IP01 identified at least four amino acids necessary for inhibition of ICAM-1 dependent cell aggregation; leucine 2, leucine 3, methionine 5, and arginine 6. Finally, we showed that cyclic IP01 can inhibit firm adhesion of neutrophils to endothelium, a critical event in inflammatory diseases, in an assay that recapitulates physiologic flow conditions. Homology of IP01 with the primary amino acid sequences of the alpha or beta subunit of LFA-1 was not identified. Thus, we identified a unique molecule that inhibits ICAM-1 dependent cell adhesion, but is not related to the primary sequence of the ICAM-1 ligand LFA-1. Due to the small size and ability to block cell-cell adhesion, IP01 may serve as a useful tool for study of ICAM-1 and LFA-1 biology as well as for the development of small molecule therapeutics.

New bioactive chalcones in propolis from El Salvador

2',3'-Dihydroxy-4,4'-dimethoxychalcone (1) and 2',3',4-trihydroxy-4'-methoxy-chalcone, two new chalcones, were isolated from propolis from El Salvador. The compounds showed significant antibacterial and antifungal activity and moderate toxicity to Artemia salina nauplii.

Structure-function studies on the new growth hormone-releasing peptide, ghrelin: minimal sequence of ghrelin necessary for activation of growth hormone secretagogue receptor 1a

The recently discovered growth hormone secretagogue, ghrelin, is a potent agonist at the human growth hormone secretagogue receptor 1a (hGHSR1a). To elucidate structural features of this peptide necessary for efficient binding to and activation of the receptor, several analogues of ghrelin with various aliphatic or aromatic groups in the side chain of residue 3, and several short peptides derived from ghrelin, were prepared and tested in a binding assay and in an assay measuring intracellular calcium elevation in HEK-293 cells expressing hGHSR1a. Bulky hydrophobic groups in the side chain of residue 3 turned out to be essential for maximum agonist activity. Also, short peptides encompassing the first 4 or 5 residues of ghrelin were found to functionally activate hGHSR1a about as efficiently as the full-length ghrelin. Thus the entire sequence of ghrelin is not necessary for activity: the Gly-Ser-Ser(n-octanoyl)-Phe segment appears to constitute the "active core" required for agonist potency at hGHSR1a.

Metabolites of caspofungin acetate, a potent antifungal agent, in human plasma and urine

Caspofungin acetate (MK-0991) is a semisynthetic pneumocandin derivative being developed as a parenteral antifungal agent with broad-spectrum activity against systemic infections such as those caused by Candida and Aspergillus species. Following a 1-h i.v. infusion of 70 mg of [(3)H]MK-0991 to healthy subjects, excretion of drug-related material was very slow, such that 41 and 35% of the dosed radioactivity was recovered in urine and feces, respectively, over 27 days. Plasma and urine samples collected around 24 h postdose contained predominantly unchanged MK-0991, together with trace amounts of a peptide hydrolysis product, M0, a linear peptide. However, at later sampling times, M0 proved to be the major circulating component, whereas corresponding urine specimens contained mainly the hydrolytic metabolites M1 and M2, together with M0 and unchanged MK-0991, whose cumulative urinary excretion over the first 16 days postdose represented 13, 71, 1, and 9%, respectively, of the urinary radioactivity. The major metabolite, M2, was highly polar and extremely unstable under acidic conditions when it was converted to a less polar product identified as N-acetyl-4(S)-hydroxy-4-(4-hydroxyphenyl)-L-threonine gamma-lactone. Derivatization of M2 in aqueous media led to its identification as the corresponding gamma-hydroxy acid, N-acetyl-4(S)-hydroxy-4-(4-hydroxyphenyl)-L-threonine. Metabolite M1, which was extremely polar, eluting from HPLC column just after the void volume, was identified by chemical derivatization as des-acetyl-M2. Thus, the major urinary and plasma metabolites of MK-0991 resulted from peptide hydrolysis and/or N-acetylation.

Immune response in cattle vaccinated against rabies

In order to determine the best type of rabies vaccine to use as a booster, 78 serological samples from singly vaccinated cattle were analyzed by counterimmunoelectrophoresis technique. The animals were divided into several groups, received the first vaccine dose with modified live virus vaccine (ERA strain) and were revaccinated with inactivated virus or modified live virus vaccines. Boosters were given at 2, 4, 8, 12 and 16 weeks following first vaccination. Results showed high titres in the cases of booster with inactivated vaccine. In all cases, however, detectable antibody titres declined quickly.

Hemolytic uremic syndrome in children: platelet aggregation and membrane glycoproteins

PURPOSE

Several mechanisms have been proposed to explain the fibrin-platelet thrombosis at the microcirculation level in the different clinical conditions of hemolytic uremic syndrome (HUS). The relationships between platelet structure and function during the first 4 weeks of evolution of the disease were studied to understand the mechanism of platelet alteration.

PATIENTS AND METHODS

Coagulation parameters, platelet counts, and aggregation were studied in 49 children, and membrane glycoproteins (GPs) in 20 of the 49 children (mean age, 17 months) with HUS (Group 2) were studied during the first 4 weeks of evolution of the disease.

RESULTS

No disseminated intravascular coagulation was found in patients with recurrent or persistent thrombocytopenia. Platelet aggregation was sequentially performed during the first weeks of evolution. All patients had a functional decrease in the acute period of HUS. Platelet GPs GPIb, GPIIbIIIa, GPIIb, and GPIIIa were evaluated. GPIIbIIIa complex presented low level and never reached normal values during the first 4 weeks of disease.

CONCLUSIONS

Platelet alterations are probably caused by multiple mechanisms: "exhausted" platelets, structural membrane alterations caused by arginine-glycine-aspartic peptide blockade, or diminished or nonfunctional membrane GPIb and GPIIbIIIa complexes.

Structure-function studies on the cyclic peptide MT-II, lactam derivative of alpha-melanotropin

The alanine-substituted and the retro, enantio, and retro-enantio analogs of MT-II, a potent agonist at melanocortin (MC) receptors, were prepared by solid-phase synthesis and evaluated for their ability to bind and activate human MC3, MC4, and MC5 receptors. Replacement of His with Ala resulted in [Ala6]-MT-II with affinity and agonist potency at human MC3, MC4, and MC5 receptors similar to MT-II. Substitution of Arg with Ala gave compound 100-fold less potent than MT-II, but replacement of Phe or Trp with Ala led to inactive compounds (at the micromolar concentrations). The significant drop of potency of the retro, enantio, and retro-enantio analogs of MT-II, demonstrated a crucial role of side-chain topology, and to a lesser degree, of peptide backbone in interactions of MT-II with the melanocortin receptors. The nuclear magnetic resonance analysis of MT-II suggested involvement of Phe and Arg residues in H-bonds stabilizing the bent conformations of the peptide backbone.

Macroscopic agglutination test for rapid diagnosis of human leptospirosis

A commercially available slide agglutination test (SAT) for the diagnosis of human leptospirosis was evaluated by comparing it to an immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) and to the microscopic agglutination test (MAT). For all 108 patients, leptospirosis was diagnosed on the basis of a fourfold or greater increase in titer by MAT (seroconversion), and all but 1 of 245 controls were MAT negative (titers, <1:100). Both SAT and the IgM ELISA failed to detect one case of infection (sensitivity, 99%). Only 3 of 145 blood donors and none of the 100 patients with other illnesses were SAT positive (specificity, 99%). The overall results were similar for the three tests; however, SAT and ELISA were statistically more sensitive as initial screening tests. For 22% of the patients, the diagnosis of leptospirosis was made earlier by SAT than by MAT. SAT detected 27 (44%) of 62 MAT-negative patients with the first serum sample. ELISA and SAT had very similar results. Follow-up of patients for 1 year after the onset of symptoms showed a decreasing rate of positivity by SAT from the third month on. The rate of positivity by ELISA decreased more slowly, to about 67% by the end of the study. By MAT all patients were persistently reactive. SAT and ELISA seem to be convenient methods for the rapid and early screening for leptospirosis and could replace the less sensitive MAT. ELISA gives less subjective results than SAT and provides information on IgM kinetics, but it can be performed only by the more sophisticated laboratories. SAT is inexpensive, can be performed more quickly and more easily than ELISA, and could be used by the less well equipped laboratories.

Use of doxycycline for leptospirosis after high-risk exposure in São Paulo, Brazil

A clinical trial pilot study, double-blinded, randomized, and controlled with a placebo to assess the effectiveness of oral doxycycline (200 mg, single dose) in preventing leptospirosis after high exposure to potentially contaminated water was performed in São Paulo, SP, Brazil. Confirmed cases were defined as those with leptospira IgM antibody and symptoms; asymptomatic cases were those presenting with IgM antibodies but no symptoms; and suspected cases were individuals with symptoms but no IgM antibody. Forty subjects were given doxycycline and 42 were given placebo. In the drug-treated group there were 2 confirmed cases, 11 asymptomatic cases, and 6 suspected cases. In the placebo group there were 5 confirmed, 6 symptomatic, and 5 suspected cases. Even though we found a protective association of doxycycline for confirmed leptospirosis cases (RR = 2.3) and seroconversion only (RR = 2.0), the association was not statistically significant because of the small number of individuals enrolled in this pilot study. We observed that the 22% of the volunteers already had IgM antibodies to leptospirosis at the first sampling. Finally, the attack rate to confirmed, asymptomatic, and suspected cases of Leptospirosis was 8.5%, 22%, and 13%, respectively, in this population.

Nuclear magnetic resonance-based model of a TF1/HmU-DNA complex

Transcription factor 1 (TF1), a type II DNA-binding protein encoded by the Bacillus subtilis bacteriophage SPO1, has the capacity for sequence-selective DNA binding and a preference for 5-hydroxymethyl-2'-deoxyuridine (HmU)-containing DNA. In NMR studies of the TF1/HmU-DNA complex, intermolecular NOEs indicate that the flexible beta-ribbon and C-terminal alpha-helix are involved in the DNA-binding site of TF1, placing it in the beta-sheet category of DNA-binding proteins proposed to bind by wrapping two beta-ribbon "arms" around the DNA. Intermolecular and intramolecular NOEs were used to generate an energy-minimized model of the protein-DNA complex in which both DNA bending and protein structure changes are evident.

[Single coronary artery and acute myocardial infarction]

We describe the rare angiographic finding of the right coronary artery arising from the middle portion of the left anterior descending coronary artery in a patient with atherosclerotic coronary artery disease and acute myocardial infarction. This anatomic variation has been previously described only four times in the modern literature.

Application of anti-leptospira ELISA-IgM for the etiologic elucidation of meningitis

Leptospirosis is one of the causes of meningitis, although its importance is not well known. In the present study we contributed to this knowledge by demonstrating specific IgM class anti-leptospira antibodies by the immunoenzymatic method ELISA in 14.6% of cerebrospinal fluid (CSF) samples from 171 patients with meningitis considered to be of indeterminate etiology. The frequencies of positivity were similar in cases with predominance of polymorphonuclear or lymphomonuclear leucocytes in the CSF. Age distribution showed a predominance of the 5 to 15 year age range (72%), and sex distribution showed a predominance of males (68%). The authors discuss the contribution of this method to the etiologic elucidation of meningitis.

Behaviour of specific IgM, IgG and IgA class antibodies in human leptospirosis during the acute phase of the disease and during convalescence

The behaviour of specific IgM, IgG and IgA class antibodies in human leptospirosis was studied by ELISA. Two groups of patients were followed up, 57 of them in the acute phase and 10 during convalescence, the latter with a mean follow-up of 10.5 months. IgM class antibodies were detected starting on the 2nd day of symptoms and were observed in 100% of patients up to the 5th month, in 66.7% up to the 7th month and in 50% up to the 12th month after the onset of symptoms. IgG class antibodies were first detected on the 7th day of symptoms in 9.1% of patients, with maximum reactivity (87.5%) between the 2nd and 3rd month, and were not detected at all in one patient. IgA class antibodies were detected starting on the 5th day of symptoms in 7.7% of patients, and in all patients on the 15th day, persisting in 100% of cases up to the 9th follow-up month. During the 12th month, they were observed in 83.3% of patients. The results indicate that an anti IgA ELISA could be of great value in seroprevalence studies on human leptospirosis.

[The serovars of Leptospira interrogans isolated from cases of human leptospirosis in São Paulo, Brazil]

Eighteen strains of L. interrogans isolated from human cases were serotyped by the agglutinin-absorption test at Instituto Adolfo Lutz in São Paulo, Brazil. Fourteen were identified as serovar copenhageni (icterohaemorrhagiae serogroup), 2 as canicola (canicola serogroup), 1 as castellonis (Ballum serogroup) and 1 as pomona serogroup (serovar not yet defined). The frequency of serovar copenhageni in 100% of the isolates in icterohaemorrhagiae serogroup is emphasized and more studies to verify the real serovars prevalence as subsidy to the epidemiology of this infection are suggested by the authors.

Ontogeny of the thymus gland of a marsupial (Monodelphis domestica)

The gray short-tailed opossum (Monodelphis domestica) has recently been established as a laboratory animal; consequently, its utility as an animal model is enhanced as more of its basic biologic characteristics become defined. To this end, we studied the ontogeny of the thymus gland in M. domestica ranging in age from the day of birth to over three years. In contrast to most Australian marsupials, M. domestica possesses only a thoracic thymus. The thymus is large in neonates and remains large until young adulthood (six months of age). It has a well-defined cortex, medulla and Hassall's corpuscles. At about six months of age, the thymuses of most animals begin to atrophy, the cortex and medulla being replaced by fat. By 28 months of age, about 50% of animals have thymuses that are completely atrophied. Thus, the ontogeny of the thymus of M. domestica appears to be similar to that of eutherian mammals.

[Syphilitic aneurysm communicating with an aortic sinus of Valsalva. A case report]

The authors present the case of a 27-year old woman with an aneurysm, possibly originating from an ectopic coronary sprout and communicating with the right anterior sinus of Valsalva. Secondary syphilitic lesions were observed. By virtue of its great size and localization, this aneurysm produced obstruction of the outlet of the right ventricle and dislocation of the left coronary artery. The authors conclude that this aneurysm was a congenital anomaly because of its great volume, configuration, the way it opened in the aortic right anterior sinus of Valsalva, the normal aortic wall and valve, and normal sinuses of Valsalva, observed at surgery. The follow-up was uneventful.

Pulmonary valvoplasty--experience of 100 cases

One-hundred patients with pulmonary valve stenosis underwent pulmonary valvoplasty, their ages ranging from 1 to 59 years. The systolic gradient across the valve ranged from 47 to 260 mm Hg (97.67 +/- 41.15) prior to the valvoplasty, and from 0 to 55 mm Hg (14.72 +/- 11.40) immediately after dilatation (P less than 0.0001). The clinical follow-up of 18.2 months of 56 patients showed a tendency for the systolic thrill to disappear, the systolic murmur became softer and there was a tendency to normalization of the electrocardiogram. A hemodynamic restudy was carried out in 54 patients and the systolic gradients across the valve ranged from 21.55 +/- 23.86. Seven patients required redilatation. In patients with hypertrophy of the infundibulum prior to valvoplasty this was observed to regress, indicating that infundibular hypertrophy is reversible.