Influence of the meso-substituents on the spectral features of free-base porphyrin.

The role of meso-substituents on the spectral features of free-base porphyrins is explored. Meso-tetra(4-pyridyl)porphyrin is compared with meso-tetra(2-thienyl)porphyrin and meso-tetra(pentafluorophenyl)porphyrin. Our results indicate that some of the asymmetric Q-bands in the free-base porphyrin tend to become symmetric relative to the adopted meso-substituent. The results show that the outlying perturbations lead the free-base quasi-degenerated Qx1, Qx2, Qy1, and Qy2 bands to be closer in energy. Combined, absorption, fluorescence and Raman spectroscopies endorse our conclusions showing that both the frequencies and the Huang-Rhys factors associated with every vibronic progression are noticeably affected by the investigated meso-substituents. Our results confirm that the B-band is also multi-featured in agreement with what is found for the Q-bands.

The influence of type I diabetes mellitus in periodontal disease induced changes of the gingival epithelium and connective tissue.

Periodontal disease constitutes the most frequent chronic diseases in human dentition. Bacterial plaque is the main etiologic agent, although it is the host immune response that causes periodontal tissue destruction. Diabetes is considered an important risk factor, not only for the onset but also for progression of the disease. The aim of this study was to analyze structural changes in the rat gingival epithelium and connective tissue in response to the experimental periodontal disease induced by the ligature technique, under the influence of diabetes. The results showed that experimental periodontal disease is characterized by marked inflammation, affecting both the epithelial and connective tissues, causing degeneration of the dermal papilla, increase in the number of inflammatory cells, destruction of reticulin fibers, and accumulation of dense collagen fibers (fibrosis). These changes were worsened by diabetes, apparently by hampering the inflammatory response and affecting tissue repair of the affected tissues.

Leishmania replication protein A-1 binds in vivo single-stranded telomeric DNA.

Replication protein A (RPA) is a highly conserved heterotrimeric single-stranded DNA-binding protein involved in different events of DNA metabolism. In yeast, subunits 1 (RPA-1) and 2 (RPA-2) work also as telomerase recruiters and, in humans, the complex unfolds G-quartet structures formed by the 3' G-rich telomeric strand. In most eukaryotes, RPA-1 and RPA-2 bind DNA using multiple OB fold domains. In trypanosomatids, including Leishmania, RPA-1 has a canonical OB fold and a truncated RFA-1 structural domain. In Leishmania amazonensis, RPA-1 alone can form a complex in vitro with the telomeric G-rich strand. In this work, we show that LaRPA-1 is a nuclear protein that associates in vivo with Leishmania telomeres. We mapped the boundaries of the OB fold DNA-binding domain using deletion mutants. Since Leishmania and other trypanosomatids lack homologues of known telomere end binding proteins, our results raise questions about the function of RPA-1 in parasite telomeres.

Conversion factors in laparoscopic cholecystectomy for acute cholecystitis.

BACKGROUND/AIMS: Although laparoscopic cholecystectomy already occupies an important role in acute cholecystitis, a high rate of conversion continues to be referred to in the series published. One of the objectives of this study is to assess the preoperative factors that might lead to conversion. METHODOLOGY: 100 laparoscopic cholecystectomies for acute cholecystitis were studied of which 24 were converted. Several parameters are taken into consideration: age, sex, ASA, echographic data, bacteriological examination of the bile, time elapsing between diagnosis and surgery, morbidity and mortality. RESULTS: The analysis made in relation to the preoperative, predetermining factors with regards to the converted cases provided the following elements in unvaried analysis: Preoperative existence of: "plastron" gallbladder (P < 0.002), temperature above 38 degrees C (P < 0.04), leucocytosis (P < 0.02)), time elapsing between diagnosis and surgery (P < 0.005), presence in the echography of pericholecystic liquid (P < 0.0005) and edema (P < 0.001); Klebsiella in the gallbladder bile (P < 0.005). Age (P = 0.136), sex (P = 0.992), associated diseases (P = 0.961), and gallbladder pathology (P = 0.282) did not present statistical differences that would prevent valid conclusions. In multi-varied analysis it was only possible to consider as independent factors the leucocytosis and the time between diagnosis and surgery. CONCLUSIONS: Laparoscopic cholecystectomy is a safe and efficient technique in the treatment of acute cholecystitis, which should constitute the first choice of treatment for this disease. However, it should be carried out within the first 4 days following surgical diagnosis.

[As the twig is bent, so is the tree inclined: children and the Liga Brasileira de Higiene Mental's eugenic programs]. / De pequenino e que se torce o pepino: a infancia nos programas eugenicos da Liga Brasileira de Higiene Mental.

Created in the early 1920s, at a moment when the country's psychiatric field was embracing the preventive outlook, the Liga Brasileira de Higiene Mental included within its members the elite of Brazilian psychiatry, along with a number of physicians and intellectuals. The article discusses the institution's proposals for intervention among children. The league ended up incorporating into its theoretical arsenal the basic themes of mental hygiene and eugenics as part of its general goal of collaborating in Brazil's process of "racial sanitation". With this objective in mind, and viewing the child as a "pre-citizen" who is a "fundamental part within the man of the future", league members included the children's issue in their projects and saw an imperative need for mental health care from early ages on.

Hematologic disorders in trauma patients during parenteral alimentation with lipids.

Total parenteral nutrition with lipids is a well-accepted modality of metabolic support in seriously ill trauma patients. Intolerance to lipid administration is unusual when dosage limits are not exceeded, and few hematologic disturbances have been recorded with modern fat emulsions. In the course of intravenous alimentation of six adults admitted for traumatic lesions, eosinophilia with or without leukocytopenia was noticed after periods of four days to five weeks. Principal clinical events and hematologic derangements were documented in this population. Sepsis was not always present in the patients by the time of the complication, and in those that did require antibiotics and other drugs, the prescription remained unchanged along the episode. Discontinuation of the nutritional regimen with lipids was followed by normalization of the hematologic profile, suggesting that an acute or sub-acute allergic reaction was responsible. The appearance of skin rash in two occasions reinforces this hypothesis, and the possibility of hemophagocytosis merits consideration in two of the cases who displayed reversible acute leukocytopenia. It is concluded that blood cell aberrations are possible during intravenous feeding with lipids in trauma subjects, but tend to respond to suppression of the lipid-containing nutritional prescription.