The transcription factor nuclear factor-kappa B and cancer

Since the discovery of nuclear factor-kappa B (NF-kappaB) in 1986, many studies have been conducted showing the link between the NF-kappaB signalling pathway and control of the inflammatory response. Today it is well known that control of the inflammatory response and apoptosis is closely related to the activation of NF-kappaB. Three NF-kappaB activation pathways exist. The first (the classical pathway) is normally triggered in response to microbial and viral infections or exposure to pro-inflammatory cytokines that activate the tripartite IKK complex, leading to phosphorylation-induced IkappaB degradation and depends mainly on IKKbeta activity. The second (the alternative pathway), leads to selective activation of p52:RelB dimers by inducing the processing of the NF-kappaB2/p100 precursor protein, which mostly occurs as a heterodimer with RelB in the cytoplasm. This pathway is triggered by certain members of the tumour necrosis factor cytokine family, through selective activation of IKKalpha homodimers by the upstream kinase NIK. The third pathway is named CK2 and is IKK independent. NF-kappaB acts through the transcription of anti-apoptotic proteins, leading to increased proliferation of cells and tumour growth. It is also known that some drugs act directly in the inhibition of NF-kappaB, thus producing regulation of apoptosis; some examples are aspirin and corticosteroids. Here we review the role of NF-kappaB in the control of apoptosis, its link to oncogenesis, the evidence of several studies that show that NF-kappaB activation is closely related to different cancers, and finally the potential target of NF-kappaB as cancer therapy.

Effects of Ultra-High Pressure Homogenization on the Cheese-Making Properties of Milk

The effects of single- or 2-stage ultra-high pressure homogenization (UHPH; 100 to 330 MPa) at an inlet temperature of 30 degrees C on the cheese-making properties of bovine milk were investigated. Effects were compared with those from raw, heat-pasteurized (72 degrees C for 15 s), and conventional homogenized-pasteurized (15 + 3 MPa, 72 degrees C for 15 s) treatments. Rennet coagulation time, rate of curd firming, curd firmness, wet yield, and moisture content of curds were assessed. Results of particle size and distribution of milk, whey composition, and gel microstructure observed by confocal laser scanning microscopy were analyzed to understand the effect of UHPH. Single-stage UHPH at 200 and 300 MPa enhanced rennet coagulation properties. However, these properties were negatively affected by the use of the UHPH secondary stage. Increasing the pressure led to higher yields and moisture content of curds. The improvement in the cheese-making properties of milk by UHPH could be explained by changes to the protein-fat structures due to the combined effect of heat and homogenization.

Immunochemistry of the Group-Specific Polysaccharide of Nocardia brasiliensis

Estrada-Parra, Sergio (Escuela Nacional de Ciencias Biológicas, México, D.F., México), Abel Zamora, and L. F. Bojalil. Immunochemistry of the group-specific polysaccharide of Nocardia brasiliensis. J. Bacteriol. 90:571-574. 1965.-The group-specific polysaccharide of Nocardia brasiliensis was further purified, yielding an amorphous white material with the following characteristics: [alpha](D) (20) = + 48; nitrogen, 0.5%; phosphorus, 0.1%; and ash as sodium, 0.8%. The polymer is made of d-arabinose and d-galactose in a molar ratio of 3:1, and no other sugars were detected. Mild hydrolysis liberates mainly arabinose. The polysaccharide consumes 3.46 mumoles of periodate per mg of polymer in 15 days at 4 C (this value remains constant after 4 more days). Oxidation results in destruction of two of the arabinose, with the formation of two glycerols after borohydride reduction and hydrolysis. The polysaccharide oxidized by periodate and reduced under mild acid hydrolysis at 20 C yields glycerol and a polymer formed by galactose and arabinose (in a ratio of 1:1) which is resistant to a second oxidation. Therefore, the polysaccharide is probably formed by a main chain of glactose linked 1,3 and arabinose linked 1,2 or 1,3 or both, and nonreducing side chains of arabofuranose residues. The intact polysaccharide cross-reacts with sera from patients with active tuberculosis, and this, as well as the homologous reaction, is abolished by oxidation with periodate.

Lowering of blood pressure leads to decreased circulating interleukin-6 in hypertensive subjects

Interleukin-6 (IL-6), the major proinflammatory cytokine, has been described to be associated with the hypertensive and atherosclerotic states. We aimed to explore whether the concentration of circulating IL-6 and adhesion molecules could be modified by decreasing blood pressure in hypertensive subjects. A total of 30 subjects (18 men), aged 34-48 years, were enrolled in this study, 17 hypertensive never-treated patients (HTA) and 13 normotensive subjects (C). HTA subjects were treated with irbesartan, 150-300 mg/day for 3 months, and serum IL-6, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, sP-selectin, sE-selectin and monocyte chemoattractant protein-1 were measured at 0 and 12 weeks. The two study groups were similar in age, body mass index (BMI) and gender. At baseline, circulating IL-6 levels, but not adhesion molecules, were significantly associated with systolic blood pressure (r=0.41; P=0.03) and BMI (r=0.53; P=0.005). Systolic and diastolic blood pressure decreased significantly (P<0.01) in parallel to serum IL-6 levels (from 3.72+/-0.82 to 3.23+/-0.19 pg/ml, P=0.02) reaching a similar concentration to normotensive patients (3.33+/-0.3 pg/ml) after treatment with irbesartan. No significant changes were observed in any other of the tested parameters. In conclusion, the treatment of high blood pressure lowers circulating IL-6 in young hypertensive patients.

17 beta-estradiol inhibits cytokine, chemokine, and chemokine receptor mRNA expression in the central nervous system of female mice with experimental autoimmune encephalomyelitis

Cytokines and chemokines govern leukocyte trafficking, thus regulating inflammatory responses. In this study, the anti-inflammatory effects of low dose 17 beta-estradiol were evaluated on chemokine, chemokine receptor, and cytokine expression in the spinal cords (SC) of BV8S2 transgenic female mice during acute and recovery phases of experimental autoimmune encephalomyelitis (EAE). In EAE protected mice, 17 beta-estradiol strongly inhibited mRNA expression of the chemokines RANTES, MIP-1 alpha, MIP-2, IP-10, and MCP-1, and of the chemokine receptors CCR1, CCR2 and CCR5 at both time points. Conversely, ovariectomy, which abrogated basal 17 beta-estradiol levels and increased the severity of EAE, enhanced the expression of MIP-1 alpha and MIP-2 that were over-expressed by inflammatory mononuclear cells in SC. 17 beta-estradiol inhibited expression of LT-beta, TNF-alpha, and IFN-gamma in SC, but had no effect on IL-4 or IL-10, indicating reduced inflammation but no deviation toward a Th2 response. Interestingly, elevated expression of CCR1 and CCR5 by lymph node cells was also inhibited in 17 beta-estradiol treated mice with EAE. Low doses of 17 beta-estradiol added in vitro to lymphocyte cultures had no direct effect on the activation of MBP-Ac1-11 specific T cells, and only at high doses diminished production of IFN-gamma, but not IL-12 or IL-10. These results suggest that the beneficial effects of 17 beta-estradiol are mediated in part by strong inhibition of recruited inflammatory cells, resulting in reduced production of inflammatory chemokines and cytokines in CNS, with modest effects on encephalitogenic T cells that seem to be relatively 17 beta-estradiol insensitive.

Estrogen treatment down-regulates TNF-alpha production and reduces the severity of experimental autoimmune encephalomyelitis in cytokine knockout mice

A shift toward Th2 cytokine production has been demonstrated during pregnancy and high dose estrogen therapy and is thought to be the primary mechanism by which estrogen suppresses the development of experimental autoimmune encephalomyelitis. However, low dose estrogen treatment is equally protective in the absence of a significant shift in cytokine production. In this study cytokine-deficient mice were treated with estrogen to determine whether a shift in Th2 cytokine production was required for the protective effects of hormone therapy. Estrogen effectively suppressed the development of experimental autoimmune encephalomyelitis in IL-4 and IL-10 knockout mice and in wild type littermate mice with a similar potency of protection. Significant disease suppression was also seen in IFN-gamma-deficient mice. The decrease in disease severity was accompanied by a concomitant reduction in the number of proinflammatory cytokine- and chemokine-producing cells in the CNS. Although there was no apparent increase in compensatory Th2 cytokine production in cytokine-deficient mice, there was a profound decrease in the frequency of TNF-alpha-producing cells in the CNS and the periphery. Therefore, we propose that one mechanism by which estrogen protects females from the development of cell-mediated autoimmunity is through a hormone-dependent regulation of TNF-alpha production.

MRI findings in Möbius syndrome: correlation with clinical features

The authors studied the MRI findings of three patients with Möbius syndrome. Möbius syndrome is a rare congenital disorder characterized by complete or partial facial diplegia accompanied by other cranial nerve palsies. MRI demonstrated brainstem hypoplasia with straightening of the fourth ventricle floor, indicating an absence of the facial colliculus. These MRI features suggest the diagnosis of Möbius syndrome and correlate with the clinical and neurophysiologic findings.

Recovery of minimal change nephrotic syndrome and acute renal failure in a patient withRenal cell carcinoma

We describe a 78-year-old patient with nephrotic syndrome due to minimal-change glomerulopathy, associated with a renal adenocarcinoma. Oliguric acute renal failure requiring hemodialysis was also observed. Surgical removal of the tumor and corticosteroid therapy resulted in resolution of the nephrotic state and improvement of the renal function. Nephrotic syndrome is an unusual complication of renal cell carcinomas, and the association of minimal-change glomerulopathy (MCG) and solid tumors is particularly uncommon. In spite of this, MCG should be considered in the nephropathies causing nephrotic syndrome and acute renal failure in patients with renal malignancies.

[Isolation of Escherichia coli O157:H7 in storm drains in the city of Mar del Plata with bacterial contamination of fecal origin]

The present study was focused on the isolation and characterization of Escherichia coli, particularly the serotype O157:H7, from five combined-sewer outflows waters, which drain into the beaches of Mar del Plata. Seventeen hemolytic uremic syndrome cases were reported in Mar del Plata during the sampling period (May 1995-April 1996) in children between 9 month- and 5 year-old, and 3 deaths were recorded. E. coli identification was carried out by biochemical tests. E. coli was detected in 75% of the samples and a total of 98 strains were selected, with 11 sorbol non-fermenting strains. The strains belonged to the O1, O6, O44, O86a, O119 and O168 serogroups. As none of the known virulence factors was detected, strains could not be grouped within any of the diarrheagenic E. coli categories. None of the E. coli strains belonged to the O157:H7 serotype, but E. coli isolation showed fecal contamination in the combined-sewer outflows. Since their waters drain into beaches for recreational use, it is necessary to emphasize the detection of E. coli that would cause severe human illness. Bacterial pollution in combined-sewer outflows draining into Mar del Plata coasts might represent a high risk for human health.

Estrogen potentiates treatment with T-cell receptor protein of female mice with experimental encephalomyelitis

Transgenic mice expressing the BV8S2 chain, which is specific for the myelin basic protein determinant Ac1-11, possess a naturally induced set of regulatory T cells directed against BV8S2. Further activation of anti-BV8S2 T cells in male mice with recombinant BV8S2 protein can inhibit IFN-gamma release by Ac1-11-specific T cells through a cytokine-driven mechanism and prevent induction of experimental autoimmune encephalomyelitis (EAE). In contrast, naive female mice possess fewer anti-BV8S2-reactive T cells, and treatment with BV8S2 delayed but did not prevent EAE. We here demonstrate that combining T-cell receptor (TCR) vaccination with supplemental estrus doses of estrogen potentiated IL-10 production by anti-BV8S2-reactive T cells and induced Ac1-11-specific T cells to produce IL-10 and TGF-beta. This combined treatment resulted in full protection against EAE, which was not observed with either therapy alone. These findings imply that supplemental estrogen can enhance the efficacy of TCR-based immunotherapy for autoimmune diseases that predominate in females.

Differences between lactate concentration of samples from ear lobe and the finger tip

Blood lactate concentrations in capillary samples obtained from the ear lobe or from the finger tip are used indistinctly, since they are considered equivalents. The aim of the study reported in this paper was to verify whether that assumption is valid due to the practical implications which any possible differences between these two sampling sites would have in the planning and assessing of an athletic training program. Twenty six healthy male athletes competing in different sports at the national level (9 rowers, 7 cyclists and 10 runners) were studied during the performance of a graded exercise test up to the point of exhaustion, on specific ergometers. In each group, capillary blood samples were obtained simultaneously from both the ear lobe and the finger tip at three different times during the test: 1) in resting conditions; 2) when exercising at a submaximal work load and 3) seven minutes after the point of exhaustion. Significant differences were found between the blood lactate concentrations of samples obtained from the ear lobe and from the finger tip (p < 0.001). The method error of repeated measurements for lactate concentrations from paired samples obtained in resting conditions was 27%, when exercising at a submaximal work load, 16% and at maximal work load, 3%. Capillary blood samples collected from the finger tip consistently showed higher values in lactate concentration than those obtained, at the same time, from the ear lobe.

Anergy induction in encephalitogenic T cells by brain microvessel endothelial cells is inhibited by interleukin-1

Experimental autoimmune encephalomyelitis (EAE) is an inflammatory disease of the central nervous system (CNS) which can be induced, in susceptible strains like Lewis rats, by transfer of activated myelin basic protein (MBP)-specific CD4+ T lymphocytes. The role of cerebral endothelium in the onset of EAE, with regard to adhesion, activation and infiltration in the CNS of encephalitogenic T lymphocytes, is not fully understood. When pretreated by interferon-gamma, the immortalized Lewis rat brain microvessel endothelial (RBE4) cells expressed major histocompatibility complex class II molecules and stimulated MBP-specific proliferation and cytolytic activity of the syngeneic encephalitogenic T cell line, designated PAS. However, RBE4-stimulated PAS lymphocytes subsequently entered an unresponsive state, known as anergy. When inoculated in syngeneic animals, anergic PAS cells, although still cytotoxic, failed to induce EAE, and no cell infiltration was detectable within CNS. The addition of interleukin-1 beta (IL-1 beta) during MBP presentation by RBE4 cells prevented T cell anergy induction, and maintained T cell encephalitogenicity, although PAS cells stimulated in these conditions caused delayed and attenuated clinical signs of EAE, with only discrete inflammatory lesions in the CNS, compared with EAE induced by PAS cells fully activated by thymic cells. Altogether, our results indicate that MBP presentation by brain microvessel endothelial cells to encephalitogenic T cells induces T cell anergy and loss of pathogenicity. In addition, IL-1 beta co-stimulation of T cells prevents anergy induction in vitro and at least partially maintains encephalitogenicity in vivo.

The Mexican experience with laparoscopic cholecystectomy and common bile duct exploration. A multicentric trial

We present here the initial data collected since the first laparoscopic cholecystectomy (LC) was performed in our country (June 1990). Twenty-one centers were surveyed (2,399 patients). The most frequent indication for LC was chronic gallstone disease (76.2%). The female population predominated (69.4%). Seven centers always perform the laparoscopic approach. Antibiotic prophylaxis is the rule, and most centers use nasogastric tube and urinary catheterization. Perioperative cholangiography is done selectively. The instrument of choice to dissect the gallbladder is the electrosurgical hook-knife. General anesthesia is preferred (97%). The complication rate was 8.87%. Injury to the bile duct and bowel perforation occurred in 0.25% and common duct stone retention occurred in 0.29% of patients. Mortality rate reached 0.12%. It is our hope that this study will help in defining the situation of LC in developing countries and that it also can serve as a first step in the organization of minimally invasive surgery groups in Mexico.