Cryptococcal Titan Cells: When Yeast Cells Are All Grown up.

Cryptococcus neoformans is a human pathogenic yeast that causes hundreds of thousands of deaths worldwide among susceptible individuals, in particular, HIV+ patients. This yeast has developed several adaptation mechanisms that allow replication within the host. During decades, this yeast has been well known for a very peculiar and unique structure that contributes to virulence, a complex polysaccharide capsule that surrounds the cell wall. In contrast to other fungal pathogens, such as Candida albicans or Aspergillus fumigatus, the role of morphological transitions has not been studied in the virulence of Cryptococcus neoformans since this yeast does not form hyphae during infection. However, in the last years, different groups have described the ability of this fungus to change its size during infection. In particular, Cryptococcus can form "titan cells," which are blastoconidia of an abnormal large size. Since their discovery, there is increasing evidence that these cells contribute, not only to long-term persistence in the host, but they can also actively participate in the development of the disease. Recently, several groups have simultaneously described different media that induce the appearance of titan cells in laboratory conditions. Using these conditions, new inducing factors and signaling pathways involved in this transition have been described. In this article, we will review the main phenotypic features of these cells, factors, and transduction pathways that induce cell growth, and how titan cells contribute to the disease caused by this pathogen.

Calculation of MP2 and coupled-cluster molecular properties using the q-integral method.

The main purpose of this paper is to report results of quantum mechanical calculation of the H(2) system using the q-Integral method with correlation corrections to the SCF (Self Consistent Field) wave functions included through the Møller-Plesset second-order perturbation (MP(2)) and Coupled-Cluster (CC) theory. Using the q-Integral method, we evaluated potential energy curves, rovibrational spectroscopy constants, rovibrational spectra, interatomic equilibrium distance and longitudinal static hyper(polarizability). All calculations were carried out through the STO-3G, STO-6G, and double-zeta (DZV) atomic basis set. The q-Integral method was implemented in the source code of the general ab initio quantum chemistry package GAMESS.

Chitosan-poly(acrylic acid) polyelectrolyte complex membranes: preparation, characterization and permeability studies.

Polyelectrolyte complex (PEC) membranes were obtained by mixing solutions of two polymers of opposite charges, chitosan (Chi) and poly(acrylic acid) PAA. Three membranes were obtained: one made of pure chitosan and two membranes with chitosan mixed with PAA at a ratio of 95:5 (one prepared using PAA solution in 3.5% formic acid, named ChiPAA3.5, and another one using a PAA solution in 10% formic acid, named ChiPAA10). The membranes were characterized by swelling experiments, FT-IR spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), mechanical properties and permeability studies in relation to a drug model (sodium sulphamerazine). The calculation of degree of ionization showed that the lower the formic acid concentration was, the higher the PAA dissociation degree. Polyelectrolyte complex formation was characterized by FT-IR. Water uptake results showed that PEC membranes were more hydrophilic than pure chitosan, ChiPAA3.5 being the most. Morphological analysis by SEM and AFM showed that PAA addition changed the membranes morphology, especially for ChiPAA3.5. Mechanical properties indicated that PEC membranes were more rigid than pure chitosan membranes and that the morphology has an influence on tensile strength values. Permeability values decreased with complex formation and were lower for ChiPAA10 than ChiPAA3.5. However, as drug concentration was increased, the difference between the two complex membranes disappeared. The results were discussed considering the drug-membrane interactions. Diffusion coefficient values indicated that ChiPAA3.5 had a higher drug retention capacity than ChiPAA10.

[Physicians denounce precariousness of reproductive health in the country and propose an addendum to the Brazilian document for the Cairo conference]. / Medicos denunciam precariedade da saude reprodutiva no Pais e propoem adendo ao documento brasileiro para Conferencia do Cairo.

PIP: On June 21, 1994, in Sao Paulo, a meeting took place of reproductive health professionals: service providers, university professors, representatives of nongovernmental organizations, secretaries of health of states and municipalities. They issued a manifesto on reproductive health in Brazil. In view of the preparations for the 3rd International Conference on Population and Development to take place in Cairo in September, 1994, it is hoped that these points will be incorporated into the official platform and in government action plans. Reproductive health is a basic human right. The growth of population decreased in Brazil in the 1980s, yet assistance in the area of reproductive health is still insufficient and unsatisfactory. The population decrease did not result in the improvement of health care and family planning. Maternal morbidity and mortality rates are still high in Brazil, especially in the north-northeastern regions, where it is 10 times higher than the national rate. There are 5 maternal deaths per 100,000 live births in Canada, 8 in the US, and 140 in Brazil. 90% of these deaths could be avoided by routine reproductive health measures. Important causes of infant mortality in Brazil are malnutrition and infectious diseases, which could be prevented by lifting the low socioeconomic level and through vaccination and birth spacing. Although fertility has been on the decline, the fertility of 10-19 year old adolescents has increased significantly, leading to high mortality rates for their infants. An estimated 1.4 million abortions occur per year in Brazil with frequent complications because of its illegal, clandestine nature. It is also estimated that 6-8 million women have been sterilized, which is the primary means of family planning because of the lack of other contraceptive options. The combination of cesarean-tubal ligation operations has been institutionalized in health services, which creates major distortions in the delivery of health care. Sexually transmitted diseases are on the rise, and HIV infections are contracted mainly from sexual intercourse and IV drug abuse. Furthermore, it is absolutely necessary for men to participate in family planning education in order to raise the status of women.^ieng

Absence of focal glomerulosclerosis in aging analbuminemic rats.

The Nagase analbuminemic rat (NAR), a mutant of the Sprague-Dawley (SD) strain, exhibits high levels of plasma cholesterol (Chol), thrombocytosis, and enhanced platelet aggregability, which might promote glomerulosclerosis (GS). To determine whether NAR are more susceptible than SD rats to aging GS, young (3-mo-old) and aging (18-mo-old) SD rats and NAR were studied. In young NAR, glomerular pressure and glomerular volume were lower, whereas total and high-density lipoprotein plasma Chol levels were higher than in young SD rats. Aging SD rats developed glomerular hypertension and hypertrophy. Less glomerular enlargement and subnormal glomerular pressures were seen in aging NAR. Enhanced platelet aggregation developed in aging SD rats, approaching the values seen in NAR. Similarly elevated levels of low-density lipoprotein Chol were seen in additional SD rats and NAR studied at 12 mo of age. Plasma triglyceride (TG) levels were lower in NAR at this age. Only SD rats developed proteinuria and exhibited GS and glomerular lipid deposits at 18 mo of age. Reduced glomerular wall stress due to lower glomerular pressure and volume as well as lower TG levels may explain the absence of GS in aging NAR despite plasma lipid and platelet abnormalities.

[Internal carotid artery in the middle ear: differential diagnosis with glomus]. / L'artère carotide interne dans l'oreille moyenne: diagnostic différentiel avec le glomus.

The authors reports on a case of pulsatile tinnitus, where otoscopy revealed a retrotympanic mass. The initial tympanic diagnosis was confirmed by a CT-scan. However, surgical exploration revealed a large artery situated on the promontory. Post-operatory arteriography confirmed that this artery in the tympanic cavity was in fact the internal carotid artery.