Technique for the performance of the nitro-blue tetrazolium (NBT) test

Immunotoxicological, histopathological, and ultrastructural effects of waterborne pyrogallol exposure on African catfish (Clariasgariepinus)

Pyrogallol is a naturally occurring polyphenol derived from natural plants, such as Acer rubrum and Eucalyptus sp. The current study was designed to evaluated pyrogallol-mediated toxicity at sublethal levels (1, 5, and 10 mg/L), derived from 96 h-LC50 values previously determined for African catfish (Clarias gariepinus). Immunotoxicological indices, histological, histochemical, and ultrastructural alterations in C. gariepinus were evaluated following a 15-day pyrogallol exposure. Pyrogallol decreased immune parameters [lysozyme activity (LYZ), immunoglobulin M (IgM), and phagocytic activity] and increased pro-inflammatory cytokines, interleukin-1 beta (IL-1β), interleukin-6 (IL-6) in the serum of C. gariepinus. In addition, histopathology analysis demonstrated that exposure to pyrogallol induced injury in the liver and spleen of fish. Cellular changes in the liver include hepatocyte hydropic degeneration, melanomacrophage, vacuolated hepatocytes, congested blood, severe structural deformation, and hemorrhage. In the spleen, ellipsoid structures, melanomacrophage centers, and infiltration of inflammatory cells were evident. Together, a high frequency of histopathological lesions was scored in both the liver and spleen of C. gariepinus, which showed a dose-dependent relationship between pyrogallol exposure and histopathological indices. Our data suggest that dysfunction in the immune system may be mediated by pyrogallol-induced changes in cytokines.

Immunomodulatory and antibacterial effect of red wine concentrate rich in a natural complex of polyphenols under diabetes mellitus

Changes in immunocompetent cells influence the course of diabetes mellitus and contribute to its complications. Thus, correction of diabetes-induced immune system disorders is vital for normalizing the state of the organism. Red wine polyphenols due to their biological activities could be considered a potential remedy for correcting diabetes. The study aimed to evaluate the antimicrobial potential and the influence of red wine polyphenols on immune system in streptozotocin-induced diabetes. We studied immunological parameters, i.e. quantity of white blood cells in peripheral blood and peritoneal macrophages, the bactericidal activity of phagocytes of blood, the activity of myeloperoxidase, and the level of cationic proteins in these cells after the administration of the polyphenol-rich red wine concentrate (PC concentrate) of known composition, obtained from Ukrainian wine, for 14th day to rats with streptozotocin-induced diabetes. The Minimal Bactericidal Concentration (MBC) of the PC concentrate was determined with the Broth Microdilution method. The PC concentrate normalized the quantity and functional activity of peripheral blood neutrophils and peritoneal macrophages, and decreased the quantity of lymphocytes under diabetes, as well as possessed the antibacterial activity against Staphylococcus aureus and Escherichia coli. Our results indicate the significant biological potential of the PC concentrate and its therapeutic relevance to correct diabetes-induced disorders.

Evaluation of Antibiotic Penicillin G Activities Based on Electrochemical Measurement of a Tetrazolium Salt

This study focused on the electrochemical properties of tetrazolium salts to develop a simple method for evaluating viable bacterial counts, which are indicators of drug susceptibility. Considering that the oxidized form of tetrazolium, which has excellent cell membrane permeability, changes to the insoluble reduced form formazan inside the cell, the number of viable cells was estimated based on the reduction current of the tetrazolium remaining in the bacterial suspension. Dissolved oxygen is an important component of bacterial activity. However, it interferes with the electrochemical response of tetrazolium. We estimated the number of viable bacteria in the suspension based on potential-selective current responses that were not affected by dissolved oxygen. Based on solubility, cell membrane permeability, and characteristic electrochemical properties of the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium, we developed a method for rapidly measuring viable bacteria within one-fifth of the time required by conventional colorimetric methods for drug susceptibility testing.

Evaluation of Bacterial Activity Based on the Electrochemical Properties of Tetrazolium Salts

This study focused on the electrochemical properties of tetrazolium salts to develop a simple method for evaluating viable bacterial counts, which are indicators of hygiene control at food and pharmaceutical manufacturing sites. Given that the oxidized form of 3-(4,5-di-methylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), which has excellent cell membrane permeability, changes to the insoluble reduced form of formazan inside the cell, the number of viable cells was estimated by focusing on the reduction current of MTT remaining in the suspension. Dissolved oxygen is an important substance for bacterial activity; however, it interferes with the electrochemical response of MTT. We investigated the electrochemical properties of MTT to obtain a potential-selective current response that was not affected by dissolved oxygen. Real-time observation of viable bacteria in suspension revealed that uptake of MTT into bacteria was completed within 10 min, including the lag period. In addition, we observed that the current response depends on viable cell density regardless of the bacterial species present. Our method enables a rapid estimation of the number of viable bacteria, making it possible to confirm the safety of food products before they are shipped from the factory and thereby prevent food poisoning.

Bacterial Ghosts of Pseudomonas aeruginosa as a Promising Candidate Vaccine and Its Application in Diabetic Rats

Infections with Pseudomonas aeruginosa (PA) pose a major clinical threat worldwide especially to immunocompromised patients. As a novel vaccine network for many kinds of bacteria, bacterial ghosts (BGs) have recently been introduced. In the present research, using Sponge-Like Reduced Protocol, P. aeruginosa ghosts (PAGs) were prepared to maintain surface antigens and immunogenicity. This is the first study, to our knowledge, on the production of chemically induced well-structured bacterial ghosts for PA using concentrations of different chemicals. The research was carried out using diabetic rats who were orally immunized at two-week intervals with three doses of PAGs. Rats were subsequently challenged either by the oral route or by the model of ulcer infection with PA. In challenged rats, in addition to other immunological parameters, organ bioburden and wound healing were determined, respectively. Examination of the scanning and transmission electron microscope (EM) proved that PAGs with a proper three-dimensional structure were obtained. In contrast to control groups, oral PAGs promoted the generation of agglutinating antibodies, the development of IFN-γ, and the increase in phagocytic activity in vaccinated groups. Antibodies of the elicited PAGs were reactive to PA proteins and lipopolysaccharides. The defense against the PA challenge was observed in PAGs-immunized diabetic rats. The resulting PAGs in orally vaccinated diabetic rats were able to evoke unique humoral and cell-mediated immune responses and to defend them from the threat of skin wound infection. These results have positive implications for future studies on the PA vaccine.

Difference between the biologic and chronologic age as an individualized indicator for the skin care intensity selection: skin topography and immune system state studies, parameter correlations with age difference

Background

Present research addresses the issue of skin aging and corresponding skin treatment individualization. Particular research question was on the developing of simplified criterion supporting patient-specific decision on the necessity and intensity of skin treatment. Basing on the published results and a wide pool of experimental data, we have formulated a hypothesis that a difference between biologic and chronologic age can be used as an express criterion of skin aging.

Methods

In present paper, we report the results of studies with 80 volunteers between 15 and 65 years of age, linking parameters reflecting immune state, skin state, and topography to the difference between biologic and chronologic age. Facial skin topography, skin moisture, sebum level, and skin elasticity were studied using commercial devices. Blood immunology studies were performed using venous blood samples. Correlations between all measured parameters and age difference were calculated. Also, cross correlations between skin cell profile and blood immune profile parameters, and skin roughness parameters were calculated.

Results

Age dependencies of the blood immunological parameters on the biologic and chronologic age difference are less pronounced as compared to the changes in skin cell profile parameters. However, the changes in the tendencies when biologic age becomes equal to chronologic one are visible for all studied parameters.

All measured skin roughness parameters show correlations with age difference, but average skin roughness and depth of the deepest profile valley have the largest correlation coefficient values. Many of the measured skin cell profile and blood immunology parameters show strong correlations with average skin roughness and deepest profile valley, with some of the coefficients exceeding 0.5–0.6.

Conclusions

Basing on own experiments and published research results, it is possible to suggest using the difference between calculated biologic age and chronologic age as an individualized criterion supporting decisions on skin treatment strategy. Further research involving larger numbers of participants and aiming on optimizing the expressions for calculating biologic age could lead to reliable and easily available express criterion supporting the decision making for an individualized skin treatment.

Role of L. plantarum KX519413 as Probiotic and Acacia Gum as Prebiotic in Gastrointestinal Tract Strengthening

Probiotics, prebiotics, and synbiotics are potential mediators to maintaining healthy intestinal flora and have garnered an area of wide research in the past few years. The current study assesses the in vivo effects of probiotic (Lactobacillus plantarum MBTU-HK1), prebiotic (acacia gum) (either singly or in combination as a synbiotic on growth performance), biochemical, hematological, physiological, and immunological effects and their role in the reduction of procarcinogen enzyme activities in male Balb/c mice. The absence of treatment-related toxicity and a normal physiological range of biochemical and hematological parameters ensure their safe consumption. The synbiotic group was found to possess lowered cholesterol levels and enhanced protein and mineral content. The probiotic and synbiotic groups reinforced immunoglobulin levels and had a modulatory effect on phagocytosis. A lymphocyte proliferation pattern suggested the stimulatory effect of synbiotic combination on splenocyte viability and proliferation. Total antioxidant capability in the liver was determined by a 2,2-diphenyl-1-picrylhydrazyl assay and all the treatment groups were found to possess increased scavenging activity. Synbiotic and prebiotic treatment was observed to lead to reduced tumor necrosis factor α (TNF-α) levels. Bacterial procarcinogenic fecal enzyme activities were found to be decreased, proving their role in the prevention of colon cancer incidence. This study proves the potency and safety of oral administration of L. plantarum MBTU-HK1 and acacia gum either individually or in combination.

Laboratory Assays of Immune Cell Function in Immunodeficiencies

Laboratory assays of immune cell function are essential for understanding the type and function of immune defects. These assessments should be performed in conjunction with a detailed history and physical examination, which should guide the evaluation of patients with a suspected immune deficiency. Laboratory assays of immune cell function are critical for assessing and demonstrating the functional impact of genetic mutations. Advances in diagnostic techniques continue to expand the ability of clinicians and researchers to understand the complex immune pathophysiology that underlies these disorders.

Estimation of phagocytic activity of polymorphonuclear leukocytes in chronic and aggressive periodontitis patients with nitroblue tetrazolium test

Context

The phagocytic activity of polymorphonuclear leukocytes (PMN) is influenced by the type of disease entity, i.e., chronic generalized periodontitis, generalized aggressive periodontitis, and chronic generalized gingivitis.

Aims

The purpose of this experimental study was to evaluate the phagocytic activity of PMN in patients with chronic generalized periodontitis, generalized aggressive periodontitis, and chronic generalized gingivitis.

Materials and Methods

A total of 60 patients, 20 patients with chronic generalized periodontitis, 20 patients with generalized aggressive periodontitis, and 20 patients with chronic generalized gingivitis were selected for this study. Blood samples were collected from the patients. Peripheral smears were prepared from the samples, and the slides were stained using nitroblue tetrazolium test, and the phagocytic activity of the neutrophils was compared using the test results.

Statistical Analysis Used

Intragroup comparison using Mann-Whitney U-test and intergroup comparison using Kruskal-Wallis one-way ANOVA test were done.

Results

The results of the present study suggest that PMN phagocytic defect was present in most of the patients affected by generalized aggressive periodontitis; however, the phagocytic defect cannot be attributed to age, sex, or clinical parameters such as the plaque index or gingival index and probing pocket depths.

Conclusions

The phagocytic activity of neutrophils in generalized aggressive periodontitis was low compared to chronic generalized periodontitis and chronic generalized gingivitis.

Adhesion Stabilized en Masse Intracellular Electrical Recordings from Multicellular Assemblies

Coordinated collective electrochemical signals in multicellular assemblies, such as ion fluxes, membrane potentials, electrical gradients, and steady electric fields, play an important role in cell and tissue spatial organization during many physiological processes like wound healing, inflammatory responses, and hormone release. This mass of electric actions cumulates in an en masse activity within cell collectives which cannot be deduced from considerations at the individual cell level. However, continuously sampling en masse collective electrochemical actions of the global electrochemical activity of large-scale electrically coupled cellular assemblies with intracellular resolution over long time periods has been impeded by a lack of appropriate recording techniques. Here we present a bioelectrical interface consisting of low impedance vertical gold nanoelectrode interfaces able to penetrate the cellular membrane in the course of cellular adhesion, thereby allowing en masse recordings of intracellular electrochemical potentials that transverse electrically coupled NRK fibroblast, C2C12 myotube assemblies, and SH-SY5Y neuronal networks of more than 200,000 cells. We found that the intracellular electrical access of the nanoelectrodes correlates with substrate adhesion dynamics and that penetration, stabilization, and sealing of the electrode-cell interface involves recruitment of surrounding focal adhesion complexes and the anchoring of actin bundles, which form a caulking at the electrode base. Intracellular recordings were stable for several days, and monitoring of both basal activity as well as pharmacologically altered electric signals with high signal-to-noise ratios and excellent electrode coupling was performed.

Attenuation of skeletal muscle and renal injury to the lower limb following ischemia-reperfusion using mPTP inhibitor NIM-811

Introduction

Operation on the infrarenal aorta and large arteries of the lower extremities may cause rhabdomyolysis of the skeletal muscle, which in turn may induce remote kidney injury. NIM-811 (N-metyl-4-isoleucine-cyclosporine) is a mitochondria specific drug, which can prevent ischemic-reperfusion (IR) injury, by inhibiting mitochondrial permeability transition pores (mPTP).

Objectives

Our aim was to reduce damages in the skeletal muscle and the kidney after IR of the lower limb with NIM-811.

Materials and methods

Wistar rats underwent 180 minutes of bilateral lower limb ischemia and 240 minutes of reperfusion. Four animal groups were formed called Sham (receiving vehicle and sham surgery), NIM-Sham (receiving NIM-811 and sham surgery), IR (receiving vehicle and surgery), and NIM-IR (receiving NIM-811 and surgery). Serum, urine and histological samples were taken at the end of reperfusion. NADH-tetrazolium staining, muscle Wet/Dry (W/D) ratio calculations, laser Doppler-flowmetry (LDF) and mean arterial pressure (MAP) monitoring were performed. Renal peroxynitrite concentration, serum TNF-α and IL-6 levels were measured.

Results

Less significant histopathological changes were observable in the NIM-IR group as compared with the IR group. Serum K⁺ and necroenzyme levels were significantly lower in the NIM-IR group than in the IR group (LDH: p<0.001; CK: p<0.001; K⁺: p = 0.017). Muscle mitochondrial viability proved to be significantly higher (p = 0.001) and renal function parameters were significantly better (creatinine: p = 0.016; FENa: p<0.001) in the NIM-IR group in comparison to the IR group. Serum TNF-α and IL-6 levels were significantly lower (TNF-α: p = 0.003, IL-6: p = 0.040) as well as W/D ratio and peroxynitrite concentration were significantly lower (p = 0.014; p<0.001) in the NIM-IR group than in the IR group.

Conclusion

NIM-811 could have the potential of reducing rhabdomyolysis and impairment of the kidney after lower limb IR injury.

HSP90 inhibitor 17AAG causes apoptosis in ATRA-resistant acute promyelocytic leukemia cells

The effects of a novel heat shock protein inhibitor, 17AAG, on established APL cell lines (NB4 and R1) were analyzed. 17AAG induces apoptosis in APL cell lines both sensitive (NB4) and resistant (R1) to ATRA after 72 h of incubation. Apoptosis occurs by a mechanism different than ATRA-mediated response, as the cells do not undergo differentiation before apoptosis. Analysis of bax and bcl-2 shows that pro-apoptotic (bax) and anti-apoptotic (bcl-2) proteins are decreased in expression after incubation with 17AAG. We believe this data supports potential clinical use of agents that target HSP90 in APL patients failing conventional therapy.

Limited use of cyclosporin A in skeletal muscle ischemia--reperfusion injury

Reperfusion injury is propagated by an inflammatory-mediated tissue edema and damage after reestablishment of vascular flow following an initial ischemic insult. In the field of transplantation, cyclosporin A(CsA) provides protection against chronic graft rejection through lymphocyte immunosuppression. Evidence for an independent protective effect of CsA against ischemia-reperfusion (IR) injury during organ transfer has prompted studies showing the benefit of CsA in various ischemia-exposed visceral organs. The authors hypothesized that CsA administration may similarly benefit IR injury after skeletal muscle amputations. To determine the effects of CsA on IR injury the authors induced 4 hours of ischemia on the gracilis muscle in a rat model. CsA (15 mg per kilogram orally) was administered in two experimental groups: (1) preischemic (N = 6): 48, 24, and 3 hours before ischemia; and (2) postischemic (N = 6): 30 minutes after induction of ischemia. The effects of CsA on IR muscle injury were observed in each of the experimental groups as well as a control group (N = 6) exposed to similar ischemia and administered a saline vehicle. Muscle viability (nitro blue tetrazolium staining) and muscle edema (wet-to-dry weight ratio) were assessed 24 hours after reperfusion. The preischemic CsA-treated gracilis muscle group demonstrated improved muscle viability (39.1 +/- 4.8%) when compared with the ischemic control muscle group (23.8 +/- 7.1%; p = 0.039). Furthermore, the preischemic CsA-treated muscle group demonstrated decreased edema (1.137 +/- 0.095 times the contralateral nonischemic muscle) when compared with the control ischemic muscle group (1.248 +/- 0.045 times the contralateral nonischemic muscle; p = 0.011). Although a trend toward improved muscle viability (32.1 +/- 4.2%) and decreased edema formation (1.200 +/- 0.062 times the contralateral nonischemic muscle) was observed in the peri-ischemic CsA-treated group when compared with the control ischemic muscle group, these differences were not significant. These observations confirm the beneficial effects of preischemic CsA therapy observed in organ transplantation research and suggest limited clinical use of peri-ischemic CsA therapy for patients with musculoskeletal amputations.

Evaluation of infectious episodes in neonates using a new procedure for the nitroblue tetrazolium test

A new procedure for the NBT slide test for peripheral blood neutrophils has been tested. 255 neonates were studied of which 63 served as control cases. Among the 114 term infants, 37 were patently infected, 30 suspicious and 47 non-infected. The latter did not significantly differ from control cases, whereas suspicious and infected infants were credited with significantly higher NBT scores. 78 infants were preterm, 31 of which were patently infected, 22 suspicious and 25 non-infected. NBT scores of infected and suspicious infants were significantly higher than those of non-infected infants, but, as previously reported, scores of preterm infants were systematically and significantly lower than those of full-term infants of the same bacteriological class. Threshold values are suggested; they could represent an accurate diagnostic aid in the early differentiation of healthy infants from high-risk infants regarding bacterial infections.

Nitroblue tetrazolium test in psoriatic arthritis, rheumatoid arthritis, and osteoarthrosis

Nitroblue tetrazolium test scores were obtained in 43 patients with psoriatic arthritis, 32 patients with rheumatoid arthritis, and 16 patients with osteoarthrosis. The mean score in all groups was similar and was higher than previously reported in patients awaiting heart surgery or with noninfective dermatoses. The test is not thought to be helpful in differentiating psoriatic arthritis from rheumatoid arthritis, and its usefulness in the diagnosis of septic arthritis superimposed on other forms of arthropathy is limited.

An appraisal of the nitroblue tetrazolium reduction test

The available literature on the nitroblue tetrazolium reduction test is reviewed. The mechanism of this test is poorly understood. There are two basic methods of performing the test, namely, the stimulated and the spontaneous methods. However, the test procedure has not been standardized, and numerous modifications have ensued resulting in a number of technics. The stimulated test has proved to be valuable for screening patients or carriers with chronic granulomatous disease of childhood. It is one of the useful tests in studying neutrophil dysfunction. On the other hand, extensive accumulated data indicate that this test, be it stimulted or spontaneous, cannot be relied upon as an absolute test to differentiate bacterial from nonbacterial infectious disease as there have been numerous false-positive and false-negative results. When this test is used, the result should be interpreted in the context of other laboratory test results and the clinical picture of the patient. Preliminary data indicate that in certain diseases, if the initial test is positive in a particular patient, it may be useful as one of the follow-up tests to ascertain the activity of the disease process.

Isolations of aerobic sporing bacilli from the tips of indwelling intravascular catheters

Following previous reports of the isolation of aerobic sporing bacilli from intravenous catheters and infusion sets, it was decided to analyse a series of catheter tip cultures to ascertain the significance of these isolations. Those catheters from which aerobic sporing bacilli were isolated behaved statistically differently from other catheters from which organisms were isolated, but were statistically similar to sterile catheters. Using the nitroblue tetrazolium (NBT) test no significant difference was found between patients with isolates of aerobic sporing bacilli and those with sterile catheters. The NBT test readily distinguished those patients from whom other organisms were isolated. In a small number of instances some evidence of a possible pathogenic role for the aerobic sporing bacillus was found, but the results clearly indicate that in most cases these organisms can be regarded as contaminants.

Human leucocytes and infection

When infection has occurred almost every type of leucocyte has a function which can contribute to the patient's recovery. Cooperation between different leucocytes takes place, and these cellular activities persist until all microorganisms have been controlled. A deficiency of one particular leucocyte function can often be compensated for by extra activity of another.

In the presence of severe infection many leucocyte functions in vitro, have been shown to be altered, often in a direction which might indicate immunodeficiency. These findings are probably secondary phenomena caused by a relative excess of antigen or of particulate debris. Various drugs can also reduce leucocyte function. All these points need consideration during the investigation of children or adults who have chronic refractory infections.

Replacement of heart valves with frame-mounted tissue grafts

Ionescu, M. I., Pakrashi, B. C., Mary, D. A. S., Bartek, I. T., and Wooler, G. H. (1974). Thorax, 29, 56-67. Replacement of heart valves with frame-mounted tissue grafts. Between April 1969 and March 1973, 213 patients had heart valve replacement with frame-mounted autologous or homologous fascia lata or with heterologous pericardial grafts. There were 111 single aortic, 95 single mitral, and seven tricuspid valve replacements.

The incidence of hospital and late mortality was each 10% for the entire series and the main causes were myocardial failure and infective endocarditis.

The majority of patients obtained significant symptomatic improvement. In patients with aortic replacement there was a statistically significant reduction in cardiothoracic ratio and in the voltage of the electrocardiogram.

Regurgitant murmurs developed in 11·6% of aortic patients and in 51·6% after mitral replacement (in 37·5% the murmur has not increased in intensity while in 14·1% it has gradually progressed). None of these mitral patients requires reoperation. Grafts in the tricuspid position have not shown signs of dysfunction or failure. Graft failure has not occurred in the aortic replacement series. From the mitral position six grafts have been removed due to failure. All six were made of autologous fascia and all showed varying degrees of thickening and retraction of cusps. There were six episodes of peripheral embolization (five transient) and one left atrial thrombosis. All seven patients are alive. Anticoagulants were not used.

The results of haemodynamic studies and in vitro hydrodynamic experiments are discussed and an explanation for graft dysfunction in the mitral position is presented.

The actuarial analysis of this series of patients over a period of up to 54 months post-operatively has shown encouraging results.