Indoleamine 2,3-dioxygenase production by human dendritic cells results in the inhibition of T cell proliferation

Dendritic cells (DCs) play a key role in the activation and regulation of B and T lymphocytes. Production of indoleamine 2, 3-dioxygenase (IDO) by macrophages has recently been described to result in inhibition of T cell proliferation through tryptophan degradation. Since DCs can be derived from monocytes, we sought to determine whether DCs could produce IDO which could potentially regulate T cell proliferation. Northern blot analysis of RNA from cultured monocyte-derived human DC revealed that IDO mRNA was induced upon activation with CD40 ligand and IFN-gamma. IDO produced from activated DCs was functionally active and capable of metabolizing tryptophan to kynurenine. Activated T cells were also capable of inducing IDO production by DCs, which was inhibited by a neutralizing Ab against IFN-gamma. DC production of IDO resulted in inhibition of T cell proliferation, which could be prevented using the IDO inhibitor 1-methyl-dl -tryptophan. These results suggest that activation of DCs induces the production of functional IDO, which causes depletion of tryptophan and subsequent inhibition of T cell proliferation. This may represent a potential mechanism for DCs to regulate the immune response.

Challenges in the application of microbial fuel cells to wastewater treatment and energy production: A mini review

Wastewater is now considered to be a vital reusable source of water reuse and saving energy. However, current wastewater has multiple limitations such as high energy costs, large quantities of residuals being generated and lacking in potential resources. Recently, great attention has been paid to microbial fuel cells (MFCs) due to their mild operating conditions where a variety of biodegradable substrates can serve as fuel. MFCs can be used in wastewater treatment facilities to break down organic matter, and they have also been analysed for application as a biosensor such as a sensor for biological oxygen which demands monitoring. MFCs represent an innovation technology solution that is simple and rapid. Despite the advantages of this technology, there are still practical barriers to consider including low electricity production, current instability, high internal resistance and costly materials used. Thus, many problems must be overcome and doing this requires a more detailed analysis of energy production, consumption, and application. Currently, real-world applications of MFCs are limited due to their low power density level of only several thousand mW/m². Efforts are being made to improve the performance and reduce the construction and operating costs of MFCs. This paper explores several aspects of MFCs such as anode, cathode and membrane, and in an effort to overcome the practical challenges of this system.

Effect of interleukin-6 deficiency on the formation of periapical lesions after pulp exposure in mice

OBJECTIVE

The multifunctional cytokine interleukin-6 (IL-6) has actions on multiple cell types, including promotion of the development of immune cells and osteoclasts. Periapical inflammation as the result of root canal infection is characterized by the accumulation of inflammatory cells and bone resorption. The effect of IL-6 on periapical lesion formation after pulpal infection is unknown. We sought to determine whether deletion of IL-6 affects periapical lesion formation after pulp exposure.

METHODS

Molar pulps of homozygous IL-6 knock-out mice (IL-6(-/-), strain B6, 129-Il6tm1Koe ) and wild-type mice (IL-6(+/+)) were exposed, and the mice were killed at 1, 2, 3, 5, and 8 weeks after the exposure. Mouse jaws were decalcified and prepared for histologic examination of periapical lesions.

RESULTS

The IL-6(-/-) mice developed larger periapical lesions more rapidly than did the IL-6(+/+) mice.

CONCLUSIONS

IL-6 deletion promoted periapical lesion development.

Poisson distribution of male mating success in laboratory populations of Drosophila melanogaster

Variation among males and females in reproductive success is a major determinant of effective population size. Most studies of male mating success in Drosophila, however, have been done under conditions very different from those in typical cultures. We determined the distribution of male mating success in five laboratory populations of D. melanogaster maintained on a 14 d, discrete generation cycle fairly representative of standard Drosophila cultures. Mating success was measured as the number of matings a male could achieve under conditions closely approximating a regular culture vial of these populations. Preliminary studies determined that most mating in these populations occurred within 14 h of the flies attaining sexual maturity. Consequently, individual virgin males were marked with white paint on their thorax, put into vials with varying numbers of unmarked virgin flies of both sexes, and monitored continuously for matings over a period of up to 14 h. At various times during the assay, virgin males and females were added to these vials in proportions simulating the pattern of eclosion in culture vials. The observed variation in the number of matings per male in the five populations was, by and large, consistent with a Poisson distribution, suggesting that male mating success in short-generation-time, discrete-generation laboratory cultures of D. melanogaster may fulfil a fundamental assumption of the Wright-Fisher model of genetic drift in finite populations.

Surface Titrations of Perlite Suspensions

The surface charge behaviour of unexpanded and expanded perlite samples in KNO3 and NaCl solutions were investigated as a function of pH and ionic strength. The solutions of KNO3 and NaCl ranging from 10(-3) to 1.0 M were used. The potentiometric titration method was used to determine the surface charge of perlite samples. It was confirmed that the perlite samples had no the point of zero charge and was negatively charged in the pH range of 3-10. The double extrapolation method was used for determining the intrinsic equilibrium constants for simple ionization and complex ionization reactions. The values obtained are pKinta2 = 2.5 and p*KintK+ = 2.3 in KNO3 solutions and pKinta2 = 3.0 and p*KintNa+ = 2.4 in NaCl solutions for unexpanded perlite, and pKinta2 = 2.6 and p*KintK+ = 2.4 in KNO3 solutions and pKinta2 = 2.7 and pKintNa+ = 2.4 in NaCl solutions for expanded perlite. Copyright 1998 Academic Press.

[Endoscopic extraperitoneal radical prostatectomy. Results after 300 procedures]

During the last decade laparoscopy has become the standard technique in the urologist's armamentarium due to constant technological advancements and refinements. Laparoscopic radical prostatectomy (LRPE), although technically demanding and associated with a considerable learning curve, has become the operative procedure of choice for patients with clinically localized prostate cancer in selected and specialized urologic centers around the globe. However, a major drawback of LRPE is the transperitoneal route of access to the extraperitoneal organ of the prostate. The principal disadvantages of LRPE are potential intraperitoneal complications. Endoscopic extraperitoneal radical prostatectomy (EERPE) is a further advancement of minimally invasive surgery as it overcomes the limitations of LRPE by the strictly extraperitoneal route of access. Based on our growing experience with this procedure we introduce several technical modifications, improvements, and refinements including a nerve-sparing, potency-preserving approach (nEERPE) in an effort to further improve this minimally invasive procedure. We report our short-term follow-up results after 300 procedures. The mean operative times were 115 min without and 150 min with lymph node dissection, in total 140 min (range: 60-260 min). There was no conversion and the transfusion rate was 1.3%. There were three early reinterventions (two bleeding and one hematoma) and five late reinterventions (four symptomatic lymphoceles and one colostomy due to a rectal fistula). Pathological stage was pT2a in 54 patients (18%), pT2b in 87 patients (29%), pT3a in 115 patients (38.3%), pT3b in 40 patients (13.3%), and pT4 in 4 patients (1.3%). Positive surgical margins were found in 9.2% (13/141) of patients with pT2 tumor and 30.3% (47/155) of patients with pT3 tumor. The mean catheterization time was 6.9 days. Six and twelve months postoperatively 86.3 and 89.6% of the patients were completely continent; 9.2% of patients needed 1-2 pads per day and 4.5 and 1.2% of patients needed more than 2 pads per day, respectively. Short-term oncological and functional results of EERPE are at least as favorable as in LRPE while operative times are shorter and complication rates are low. EERPE is a technical advancement because it combines the advantages of a totally extraperitoneal access with the advantages of a minimally invasive procedure.

Number of women needed in a prospective trial to prove potential cardiovascular benefit of hormone replacement therapy

INTRODUCTION

Hormonal replacement therapy (HRT) may be beneficial for the cardiovascular system if hormones are given shortly after the onset of menopause. So far, no randomized trial has provided conclusive results.

MATERIALS AND METHODS

Based on Belgian population data, we calculated the number of women that should be included in a prospective double-blinded study to prove a potential cardiovascular benefit of HRT. Sample size calculations were based on the extrapolation of empirical observations made in three large databases from epidemiological studies carried out in Belgium during the past 20 years.

RESULTS

The 10-year mortality varies with the age at which women are included in the observation. In the normal Belgian female population, the cardiovascular mortality risk is 0.85% and 1.58% for women aged 50-54 and 55-59 years, respectively. To prove that HRT induces a decrease of 10-year mortality of 30% in a normal population of 50-54-year-old women, 34 630 subjects would have to be included; for reductions of 20% and 10%, the numbers would be, respectively, 82 468 and 348 056. To prove a significant decrease in 10-year mortality starting with a normal population with an average age of 55-59 years, the numbers needed for hypothetical reductions of 30%, 20% and 10% would be, respectively, 18 514, 44 072 and 185 936.

CONCLUSION

If cardiovascular mortality is the study end-point, it is obvious that such a study will be a gigantic task. Taking cardiovascular morbidity as the end-point, such a study would be feasible.

[Laparoscopic extraperitoneal radical prostatectomy: changes in time and updated results]

Laparoscopic radical prostatectomy has been established and adopted by specialized urologic centers around the world as the primary approach to the surgical management of localized prostate cancer. Urologists are on a continuous search for development of technical modifications and refinements, to reduce morbidity and ameliorate clinical and quality of life outcome. In 2002 we have initially reported our technique and experience with the totally extraperitoneal endoscopic radical prostatectomy (EERPE). In the present review paper we present the evolution of the technique and the latest results.

[Hepatectomy in intrahepatic lithiasis]

STUDY AIM

The aim of this study was to report the immediate results of a series of 65 hepatic resections for hepatolithiasis performed in Vietnam.

PATIENTS AND METHOD

From 1986 to 1998, 44 men and 21 women (mean age: 40 years) underwent hepatic resection for hepatolithiasis. Fourty patients had previously undergone one or several operations for hepatolithiasis. The procedure was performed on emergency in 25 patients. Indications for hepatic resection were: angiocholitis and liver abscess in 22 cases, stones closely inserted in the biliary duct in 20 cases, hemobilia in 12 cases, stones located above a biliary stricture in 8 cases and stones associated with a postoperative biliary fistula in 3 cases. Liver resections (minor in 61 patients, including 55 left lobectomies, and major in 4 patients) were performed through transhepatic approach according to the Ton That Tung technique and followed by an external biliary drainage with a Kehr tube.

RESULTS

There were 6 postoperative deaths (9%), 3 due to septic shock, 2 to cachexia, and 1 to liver failure. The 15 patients with complications recovered with conservative therapy. Bile infection was present in 93%, mostly with Escherichia coli and Enterobacter. Pigmented stones were usually found.

CONCLUSION

Vietnam is a country with high incidence of hepatolithlasis. Hepatic resection is an adequate treatment for localized intrahepatic bile duct stones when the involved segment including biliary strictures and calculi can be completely removed. The procedure may be performed on emergency for liver abscess, or hemobilia.

Facial emotion processing hemispheric bias is weakly associated with handedness, autistic traits and biological sex, but not age

BACKGROUND

Right-hemisphere brain regions are strongly implicated in facial emotion processing (FEP), a phenomenon termed right-hemispheric bias. Variability in FEP hemispheric bias is thought to underpin differences in facial emotion recognition ability and has been associated with age, handedness, biological sex, and autistic traits. However, findings from research to date investigating factors associated with FEP hemispheric bias have been inconsistent.

OBJECTIVE

To examine if FEP hemispheric bias can be predicted by individual factors such as age, biological sex, handedness, and autistic traits.

METHODS

427 adults recruited from the general population aged 18-67 years completed the Autism-spectrum Quotient. We also assessed covariates previously linked with FEP hemispheric bias including age, handedness, and biological sex. FEP hemispheric bias was indexed using laterality quotients calculated from a Chimeric Faces Task, where participants indicated which of two identical (but mirrored) half-emotional half-neutral (no emotion) chimeric faces were more emotive.

RESULTS

Linear regression models revealed that (1) handedness predicted FEP hemispheric choice bias, (2) the attention switching Autism-spectrum Quotient subscale predicted FEP hemispheric reaction time bias, and (3) the imagination Autism-spectrum Quotient subscale predicted FEP hemispheric reaction time bias for males, but not females.

CONCLUSIONS

These findings indicate that the relationship between autistic traits and FEP hemispheric bias is nuanced. Additionally, handedness influences hemispheric bias effects during FEP. Future research should endeavour to investigate if FEP hemispheric bias is dependent on the emotion being observed and consider using more direct measures of hemispheric bias.

High repetition-rate foam targetry for laser-plasma interaction experiments: Concept and preliminary results

Foam targets have gained considerable importance over the last decade in laser-matter interaction. They find widespread applications such as in inertial confinement fusion and secondary sources for particles and radiation. At the same time, the advent of high repetition-rate laser systems, be they short-pulse in the tens of femtosecond regime or in the kilo-Joule nanosecond regime, calls for equally high repetition rate targetry systems. A well-established repetition-rate targetry system is the tape target. In this article, we present the successful marriage of a tape target delivery system with 3D-printed foam targets produced by two photon polymerization.

N,N'-bridged heterocyclic bis-iminium salts as potent antimalarial agents against multi-resistant Plasmodium falciparum

The emergence of Plasmodium resistance to past and newly introduced antimalarial drugs reinforces the need for new antimalarial agents with innovative mechanisms of action. In this regard, the search for new redox-cycling compounds might offer an interesting approach to treat malaria since P. falciparum is sensitive to oxidative stress. Based on our experience in the design of powerful organic reducers, we undertook here the synthesis and evaluation of different families of N-heterocyclic iminium salts that could provide more selective redox-cycling candidates against the K1 multi-resistant Plasmodium falciparum strain (PfK1). Bis-aminopyridinium salts emerged as the most promising candidates, exhibiting nanomolar antiplasmodial activity comparable to that of methylene blue. The biological study also underlined the positive impact on the in vitro activity of electron-donating groups and bis-salt forms, likely due to simultaneous bivalent interactions with the target. Our investigations revealed differences in the mechanism of action according to the heterocycle nature, highlighting an original mechanism for bis-aminopyridinium derivatives, different from that of chloroquine.