[Evaluation of bacterial contamination in disinfectants for domestic use]. / Avaliação da contaminação bacteriana em desinfetantes de uso domiciliar.

OBJECTIVE: To evaluate disinfectants for domestic use for the presence of bacteria, identify them, and determine their tolerance level to benzalkonium chloride. METHODS: Fifty-two samples of commercially available disinfectants for domestic use were acquired at random in the metropolitan area of São Paulo, Brazil, and analyzed to detect the presence of bacterial contaminants. The isolated organisms were identified and their tolerance level to benzalkonium chloride was determined by broth macrodilution method. RESULTS: Sixteen (30.77%) of fifty-two disinfectants sampled were contaminated by Gram-negative bacteria, with counts varying between 10(4) and 10(6) UFC/ml. Alcaligenes xylosoxidans, Burkholderia cepacia and Serratia marcescens were the predominant organisms found. The minimum inhibitory concentration (MIC: mg/ml) of benzalkonium chloride for these bacteria were 2.48, 1.23 and 0.30 to S. marcescens, A. xylosoxidans and B. cepacia, respectively. CONCLUSIONS: The disinfectant formulation containing quaternary ammonium compounds (QACs) may be exposed to contamination by Gram-negative bacteria. The MICs of benzalkonium chloride against the isolated bacteria were low, indicating that the bacteria grown in culture media without QACs lost their tolerance to this biocide.

Crystals of Rous sarcoma virus capsid protein show a helical arrangement of protein subunits.

Crystals of Rous sarcoma virus (RSV) capsid protein diffract X rays to 3.5 A resolution and belong to the monoclinic space group C2 with unit cell parameters a = 374.4 A, b = 128.1 A, c = 200.2 A, and beta = 121.8 degrees. One asymmetric unit of the crystal may contain between 28 and 35 molecules, based on reasonable crystal density assumptions. A self-rotation function and Patterson synthesis suggest that RSV capsid protein crystallizes as a helical array. The determinants of the viral particle morphology are not encoded in the capsid alone. The assembly of a helical array in the crystal reflects the absence of any conformational switching. However, it is expected that the subunit interactions seen in the crystal will be preferred and will relate to those found in the immature or mature virion.

Fc portion of intravenous immunoglobulin suppresses the induction of experimental allergic neuritis.

To clarify how intravenous immunoglobulin (IVIg) acts on Guillain-Barré syndrome, we investigated the effects of intact-type IVIg treatment on experimental allergic neuritis (EAN) induced by immunizing with synthetic peptide from bovine P2 protein. Treatment with intact-type IVIg (400 mg/kg/day) on days 0, 7, 14, 15 and 16 after immunization prevented the paralysis, whereas treatment with F(ab')2 failed to alter the clinical course. Intact-type IVIg treatment given on days 0 and 1 showed almost the same efficacy. These results suggest that intact-type IVIg is superior to F(ab')2 in ameliorating the clinical course of EAN and that the Fc portion might affect the immune system.

Possible mechanism of intravenous immunoglobulin treatment on anti-GM1 antibody-mediated neuropathies.

Anti-GM1 antibody may function in disease development in some patients with Guillain-Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy and multifocal motor neuropathy. Intravenous immunoglobulin (IVIg) therapy is effective in these neuropathies, but the mechanism by which IVIg acts is not clear. To test whether it has anti-idiotypic activity on anti-GM1 antibody, we investigated whether IVIg inhibits the binding of cholera toxin to GM1. It inhibited the reaction between cholera toxin and GM1 mediated by F(ab')2 fragments of IgG. Treatment with sialidase did not inhibit the binding of cholera toxin to GM1, whereas denaturation with guanidine did. This suggests that the GM1 epitope in IVIg has peptide and not carbohydrate structures. The variable region of IVIg may bind to anti-GM1 antibody, as well as to cholera toxin, thereby neutralizing the pathogenic effects of the autoantibody.

[Responses of cytokines, acute phase proteins, and polymorphonuclear cell elastase to surgical stress in the patients with esophageal cancer].

The serum levels of cytokines (interleukin-1 beta; IL-1 beta, interleukin-6; IL-6, tumor necrosis factor alpha; TNF alpha), and acute phase proteins (CRP, alpha 1-antitrypsin; alpha 1-AT, alpha 1-acid glycoprotein; alpha 1-AG, fibrinogen; FBG, pancreatic secretory trypsin inhibitor; PSTI), and the plasma concentration of polymorphonuclear cell elastase; PMN-E and white blood cell counts were measured in 18 patients with esophageal cancer who underwent radical esophagectomy through right thoracotomy and reconstruction with gastric tube. Peripheral venous blood samples were obtained before and just after operation, and on the 1st, 2nd, 3rd, 7th and 14th post-operative day. The serum concentrations of IL-6 just after operation were significantly correlated with volume of blood loss during operation and duration of thoracotomy. Plasma PMN-E levels just after operation seemed to be correlated with those factors, but its correlation was not statistically significant. Serum IL-6 levels began to increase markedly just after operation, and reached the maximum by the 1st post-operative day. This elevation preceded that of acute phase proteins, indicating that IL-6 may induce the production of acute phase proteins in vivo. Furthermore, peak serum values of IL-6 after operation were correlated with volume of blood loss and duration of thoracotomy. These results suggest that elevation of IL-6 and PMN-E levels may reflect the degree of surgical stress, and the measurement of IL-6 and PMN-E is useful for the early detection of an inflammatory response.

Different NH2-terminal form with 12 additional residues of alpha 2-plasmin inhibitor from human plasma and culture media of Hep G2 cells.

alpha 2-Plasmin inhibitor (alpha 2PI) was purified from plasma or from the culture media of Hep G2 cells by one-step immunoaffinity chromatography procedure. Majority of alpha 2PI purified from plasma was the previously recognized plasma alpha 2PI with NH2-terminal Asn (Asn-alpha 2PI), whereas majority of alpha 2PI purified from the culture media was retaining the "pro" peptide of 12 amino acids with NH2-terminal Met (Met-alpha 2PI). When Hep G2 cells were cultured in serum-free media, the alpha 2PI secreted to the media was totally in a form of Met-alpha 2PI. Incubation of Met-alpha 2PI with human plasma induced the complete conversion of Met-alpha 2PI to Asn-alpha 2PI. The results indicate that alpha 2PI is synthesized and secreted from liver cells as Met-alpha 2PI and Met-alpha 2PI is converted to Asn-alpha 2PI by proteolytic cleavage in plasma during the circulation.

[A case of cerebral vascular disease associated with prosopagnosia and minor hemisphere syndrome (author's transl)].

A case of "apractognosia", a syndrome of minor hemisphere, and prosopagnosia was described. A 68 years old, right handed, hypertensive man who had experienced an episode of left hemiparesis of several weeks' duration developed a syndrome of minor hemisphere, metamorphopsia, visuoconstructive disability, spatial dysgraphia, topographical and geographical disorientation and dressing apraxia, with associated left homonymous hemianopsia. A right occipital lesion was disclosed by an isotopic brain scan and a CT scan. The CT scan also disclosed a generalized cerebral atrophy. Memory disturbance, both verbal and visual, was observed. Verbal memory was examined by coupled words test, digit span and 10-words learning test, and visual memory by spatial pointing span and memorizing unfamiliar faces. The patient was able to differentiate unfamiliar faces, but was not able to memorize them correctly. Although the patient has complained of a disturbance of recognizing familiar faces (prosopagnosia), but actually, sometimes he was able to recognize the members of his family by the faces and sometimes he was not. He has stated that he could not recall familiar faces. The authors suggested prosopagnosia is, as Benton (1975) has supposed, considered to be the limited disorders of memory and association.

Acute multiple gastric ulcers in the pyloric antrum.

Acute prepyloric hemorrhagic erosions occasionally progress to symmetrical ulcers. Cytomegalic inclusion bodies were frequently seen, a history of alimentary allergens, excessive alcohol intake or coffee drinking was common. Hyperchlorhydria which decreased spontaneously was found in 89% during the acute attack.