Topical corticosteroids inhibit allergic skin inflammation but are ineffective in impeding the formation and expansion of resident memory T cells

BACKGROUND

Tissue-resident memory T (TRM ) cells are detrimental in allergic contact dermatitis (ACD), in which they contribute to the chronicity and severity of the disease.

METHODS

We assessed the impact of a standard topical corticosteroid (TCS) treatment, triamcinolone acetonide (TA), on the formation, maintenance and reactivation of epidermal TRM cells in a preclinical model of ACD to 2,4-dinitrofluorobenzene. TA 0.01% was applied at different time points of ACD response and we monitored skin inflammation and tracked CD8+ CD69+ CD103+ TRM by flow cytometry and RNA sequencing.

RESULTS

The impact of TA on TRM formation depended on treatment regimen: (i) in a preventive mode, that is, in sensitized mice before challenge, TA transiently inhibited the infiltration of effector T cells and the accumulation of TRM upon hapten challenge. In contrast, (ii) in a curative mode, that is, at the peak of the ACD response, TA blocked skin inflammation but failed to prevent the formation of TRM . Finally, (iii) in a proactive mode, that is, on previous eczema lesions, TA had no effect on the survival of skin TRM , but transiently inhibited their reactivation program upon allergen reexposure. Indeed, specific TRM progressively regained proliferative functions upon TA discontinuation and expanded in the tissue, leading to exaggerated iterative responses. Interestingly, TRM re-expansion correlated with the decreased clearance of hapten moieties from the skin induced by repeated TA applications.

CONCLUSIONS

Our results demonstrate that TCS successfully treat ACD inflammation, but are mostly ineffective in impeding the formation and expansion of allergen-specific TRM , which certainly restricts the induction of lasting tolerance in patients with chronic dermatitis.

Emergence of carbapenem-resistant Pseudomonas alcaligenes and Pseudomonas paralcaligenes clinical isolates with plasmids harbouring bla IMP-1 in Japan

Introduction. The emergence of carbapenem-resistant Pseudomonas species producing metallo-β-lactamase (MBL) has become a serious medical problem worldwide. IMP-type MBL was firstly detected in 1991 in Japan. Since then, it has become one of the most prevalent types of MBLs.Hypothesis/Gap statement. Avirulent species of Pseudomonas, such as Pseudomonas alcaligenes, function as reservoirs of drug resistance-associated genes encoding carbapenemases in clinical settings.Methodology. Active surveillance for carbapenem-resistant Gram-negative pathogens was conducted in 2019 at a hospital in Tokyo, Japan. Of the 543 samples screened for carbapenem-resistant isolates, 2 were species of Pseudomonas. One was from a stool sample from a medical staff member, and the other was from a stool sample from a hospitalized patient.Results. Whole-genome sequencing showed that the former isolate was a strain of P. alcaligenes, and the latter was a strain of Pseudomonas paralcaligenes, a species close to P. alcaligenes. Both isolates were resistant to all carbapenems and harboured bla _IMP-1 genes encoding IMP-1 MBL, which conferred resistance to carbapenems. The bla _IMP-1 genes of P. alcaligenes and P. paralcaligenes were located on the plasmids, pMRCP2, 323125 bp in size, and pMRCP1333, 16592 bp in size, respectively. The sequence of 82 % of pMRCP2 was 92 % similar to the sequence of a plasmid of P. aeruginosa PA83, whereas the sequence of 79 % of pMRCP1333 was >95 % similar to the sequence of a plasmid of Achromobacter xylosoxidans FDAARGOS 162. The genomic environments surrounding the bla _IMP-1 of pMRCP2 and pMRCP1333 differed completely from each other.Conclusions. These results indicate that the two isolates acquired bla _IMP-1 from different sources and that P. alcaligenes and P. paralcaligenes function as vectors and reservoirs of carbapenem-resistant genes in hospitals.

Pseudomonas paralcaligenes sp. nov., isolated from a hospitalized patient

A Gram-stain-negative, aerobic, rod-shaped, non-endospore-forming bacterium, designated as strain MRCP1333^T, was isolated from a faecal sample from a hospital patient in Japan. MRCP1333^T grew at temperatures of 15-40 °C (optimum 25-35 °C), with 1.0-3.0 % (w/v, 171-513 mM) NaCl [optimum 1-2 % (w/v), 171-342 mM], and at pH 6.0-9.5 (optimum pH 7.0-8.0). The results of phylogenetic analysis based on the sequences of the 16S rRNA gene and the 53 genes encoding the bacterial ribosome protein subunits indicated that MRCP1333^T represented a member of the Pseudomonas aeruginosa group, most closely related to Pseudomonas alcaligenes. Whole-genome comparisons, using average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity, confirmed that MRCP1333^T represented a distinct species in the P. aeruginosa group. Phenotypic characterization tests demonstrated utilization by this strain of citrate, glycerol, and d-malic acid, the ability to reduce nitrite to nitrogen and the ability of this strain to grow in the presence of minocycline and tetrazolium blue, distinguishing this strain from P. alcaligenes and other closely related species of the P. aeruginosa group. The major fatty acids of MRCP1333^T were summed feature 8 (C_18 : 1ω7c/C_18 : 1ω6c; 38.4 %), summed feature 3 (C_16 : 1ω7c/C_16 : 1ω6c; 21.1 %) and C_16 : 0 (20.6 %). The DNA G+C content of MRCP1333^T was 66.5 mol%. Genetic and phenotypic evidence indicated that MRCP1333^T should be classified as representing a novel species, for which the name Pseudomonas paralcaligenes sp. nov. is proposed. The type strain is MRCP1333^T (=LMG 32254^T,=JCM 34250^T).

Why does sweat lead to the development of itch in atopic dermatitis?

Sweating plays an important role in maintaining temperature homeostasis in humans. However, under certain circumstances, sweat can cause itching. For example, when excessive sweat accumulates on the skin surface for a long period, miliaria can develop and cause itching. Subjects with dermatoses, such as atopic dermatitis (AD), suffer from itch when exposed to heat or psychological stresses, which are also known perspiration stimuli. Recently, some mechanisms of sweat-induced itch have been revealed. For instance, attenuated sweating ability is observed in subjects with AD, causing heat retention, skin dryness, and high susceptibility to itch. Furthermore, the decreased tight junction of the sweat gland in AD leads to sweat leakage in the dermis, which could be designated as a "sweat endocrine response" and may be the cause of tingling itch during sweating. Additionally, metabolomic analysis of sweat from patients with AD revealed that glucose concentration in sweat increases according to disease severity. Sweat with elevated glucose concentration retards the recovery of the damaged skin barrier and may promote itching. This viewpoint essay outlines the relationship between sweat and itch based on recent evidence.

Sweat in the pathogenesis of atopic dermatitis

Sweat is a transparent hypotonic body fluid made from eccrine sweat glands. Various ingredients contained in sweat are involved in a broad sense in skin homeostasis including temperature regulation, skin moisture, and immune functions. Thus, sweat plays a major role in maintaining skin homeostasis. Therefore, abnormal sweating easily compromises human health. For example, in atopic dermatitis (AD), perspiration stagnation accompanying sweat tube or sweat pore blockage, leakage of perspiration from the sweat gland to the outside tissue, and impaired secretion of sweat from the sweat gland are confirmed. In recent years, the hypothesis that atopic dermatitis is a sweat stasis syndrome has been clarified by the establishment of a sweat and sweat gland dynamic analysis technique. Secretion of sweat and leakage into tissues is caused by dermatitis and is thought to promote itching. Furthermore, from the metabolomic analysis of sweat of patients with atopic dermatitis, it was confirmed that the glucose concentration in AD sweat increased according to severity and skin phenotype, suggesting that elevated glucose affected the homeostasis of the skin. Multifaceted analyses of sweat from subjects with AD have revealed new aspects of the pathology, and appropriate measures to treat sweat can be expected to contribute to long-term control of AD.

Report from the fifth international consensus meeting to harmonize core outcome measures for atopic eczema/dermatitis clinical trials (HOME initiative)

This is the report from the fifth meeting of the Harmonising Outcome Measures for Eczema initiative (HOME V). The meeting was held on 12-14 June 2017 in Nantes, France, with 81 participants. The main aims of the meeting were (i) to achieve consensus over the definition of the core domain of long-term control and how to measure it and (ii) to prioritize future areas of research for the measurement of the core domain of quality of life (QoL) in children. Moderated whole-group and small-group consensus discussions were informed by presentations of qualitative studies, systematic reviews and validation studies. Small-group allocations were performed a priori to ensure that each group included different stakeholders from a variety of geographical regions. Anonymous whole-group voting was carried out using handheld electronic voting pads according to predefined consensus rules. It was agreed by consensus that the long-term control domain should include signs, symptoms, quality of life and a patient global instrument. The group agreed that itch intensity should be measured when assessing long-term control of eczema in addition to the frequency of itch captured by the symptoms domain. There was no recommendation of an instrument for the core outcome domain of quality of life in children, but existing instruments were assessed for face validity and feasibility, and future work that will facilitate the recommendation of an instrument was agreed upon.

Sweat glucose and GLUT2 expression in atopic dermatitis: Implication for clinical manifestation and treatment

Sweat includes active components and metabolites, which are needed to maintain skin homeostasis. Component changes in sweat derived from atopic dermatitis (AD) have been reported. To investigate the influence of sweat components on the pathogenesis of AD, we performed a multifaceted assessment, including nuclear magnetic resonance spectroscopy-based metabolomic analysis, and linked these features to clinical features of AD. Distinctive properties of AD sweat are the quite-variation in protein, anti-microbial peptides and glucose concentrations. pH, sodium, and other salt levels in sweat of AD were comparable to that of healthy subjects. Sweat from AD patients with acute inflammation had a more prominent increase in glucose concentration than sweat from healthy individuals or those with AD with chronic inflammation. Topical glucose application delayed recovery of transepidermal water loss in barrier-disrupted mice. Furthermore, the glucose transporter GLUT2 was highly expressed in the lumen of sweat glands from AD patients. AD patients with chronic inflammation had significantly increased GLUT2 mRNA expression and near normal sweat glucose levels. Despite the small sample size in our study, we speculate that the increased glucose levels might be affected by AD severity and phenotype. We hope that this report will bring novel insight into the impact of sweat components on the clinical manifestation of AD.

Accumulation of a soluble form of human nectin-2 is required for exerting the resistance against herpes simplex virus type 2 infection in transfected cells

Cell entry of herpes simplex virus type 2 (HSV-2) requires the interaction of viral glycoprotein D (gD) with the receptor nectin-1 and herpesvirus entry mediator (HVEM). In addition, it is known that nectin-2 is also functional as a receptor for HSV-2, although the binding to the gD is weak. To examine an antiviral potential of a soluble form of human nectin-2 (hNectin-2Ig), transfected Vero cells expressing the entire ectodomain of nectin-2 fused to the Fc portion of human IgG were established. Specific binding of hNectin-2Ig to HSV-2 gD was confirmed by ELISA. Competitive ELISA demonstrated that accumulation of hNectin-2Ig in transfected cells increased significantly in a cell culture time dependent manner. Viral growth of several HSV-2 strains was significantly inhibited in the transfected cells that were cultured for 72 hr compared with control Vero cells, but not in cells that were cultured for 24 hr. These results indicate that accumulation of a soluble form of nectin-2 is required for exerting the resistance against HSV-2 infection.

Cerebellar Hypoplasia Associated with an Avian Leukosis Virus Inducing Fowl Glioma

Fowl glioma-inducing virus (FGV), which belongs to subgroup A of avian leukosis virus (ALV), shows tumorigenicity and pathogenicity, mainly in the nervous system, and causes astrocytoma and perineurioma. Apart from these neoplasms, cerebellar anomaly was found in chickens infected with FGV in ovo. The study reported here describes the morphologic characteristics of the affected cerebellum. Specific-pathogen-free chickens (C/O) were inoculated with FGV through the yolk sac on the 7th day of incubation. The cerebellar anomaly included diffuse depletion of granular cells of the internal granular layer (IGL), remnants of the external granular layer (EGL), and disorganization of the Purkinje cell layer. These cerebellar changes were observed in all birds except one. in the infected embryos, the EGL was thicker and had an irregular arrangement with a thin molecular layer (ML) and IGL, compared with the control. The granular cells were immunohistochemically positive for ALV common antigen. immunohistochemical analysis for vimentin revealed disarrangement and decreased number of Bergmann's fibers. Use of the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling method and electron microscopy indicated that apoptotic granular cells were frequently observed in the EGL and ML. These results suggested that the cerebellar anomaly was hypoplasia, principally resulting from the apoptosis of granular cells in the EGL and ML caused by FGV infection and that the cell loss induced obstruction of granular cell migration and disarrangement of Bergmann's fibers in the ML.

Immunophenotypic profile and increased risk of hospital admission for infection in infants born to female kidney transplant recipients

Children born to female kidney recipients are exposed to immunosuppressive drugs during gestation. Little is known about their immune system at birth or in the long term. Twenty-eight children born to female kidney recipients and 40 full-term children born to healthy mothers were evaluated. T, B, NK, NKT, γδT cells were assessed by flow cytometry and functional evaluation of T and dendritic cells after in vitro activation was performed at birth and at 8 months of age. At birth, infants born to female kidney recipients showed lower numbers of CD4+ T, NKT and intense reduction of B cells (median cells/mm(3) , transplant: 153.7 X control: 512.4; p < 0.001). There was also a reduced percentage of activated CD8+ T and of CD4+ regulatory T cells. Activated memory and exhausted memory B cells showed higher percentages among children exposed to immunosuppressors when compared to control group. At 8 months, most immune alterations were no longer observed, but four children still had low numbers of some lymphocyte subsets at this age. Children born to female kidney recipients had 4.351 (95% CI: 1.026-15.225; p = 0.046) higher risk of hospital admission in the first months of life-some, with severe clinical manifestations-than those born to healthy women.

Sweat, the driving force behind normal skin: an emerging perspective on functional biology and regulatory mechanisms

The various symptoms associated with excessive or insufficient perspiration can significantly reduce a patient's quality of life. If a versatile and minimally invasive method could be established for returning sweat activity to normalcy, there is no question that it could be used in the treatment of many diseases that are believed to involve perspiration. For this reason, based on an understanding of the sweat-gland control function and sweat activity, it was necessary to conduct a comprehensive search for the factors that control sweating, such as the central and peripheral nerves that control sweat-gland function, the microenvironment surrounding the sweat glands, and lifestyle. We focused on the mechanism by which atopic dermatitis leads to hypohidrosis and confirmed that histamine inhibits acetylcholinergic sweating. Acetylcholine promotes the phosphorylation of glycogen synthesis kinase 3β (GSK3β) in the sweat-gland secretory cells and leads to sensible perspiration. By suppressing the phosphorylation of GSK3β, histamine inhibits the movement of sweat from the sweat-gland secretory cells through the sweat ducts, which could presumably be demonstrated by dynamic observations of the sweat glands using two-photon microscopy. It is expected that the discovery of new factors that control sweat-gland function can contribute to the treatment of diseases associated with dyshidrosis.

Acetyl-L-carnitine normalizes the impaired long-term potentiation and spine density in a rat model of global ischemia

As a consequence of an ischemic episode, energy production is disturbed, leading to neuronal cell death. Despite intensive research, the quest for promising neuroprotective drugs has largely failed, not only because of ineffectiveness, but also because of serious side-effects and dosing difficulties. Acetyl-l-carnitine (ALC) is an essential nutrient which plays a key role in energy metabolism by transporting fatty acids into mitochondria for β-oxidation. It is an endogenous compound and can be used at high dose without toxicity in research into ischemia. Its neuroprotective properties have been reported in many studies, but its potential action on long-term potentiation (LTP) and dendritic spine density has not been described to date. The aim of the present study was an evaluation of the possible protective effect of ALC after ischemic insults inflicted on hippocampal synaptic plasticity in a 2-vessel occlusion (2VO) model in rats. For electrophysiological measurements, LTP was tested on hippocampal slices. The Golgi-Cox staining technique was used to determine spine density. 2VO resulted in a decreased, unstable LTP and a significant loss of dendritic spines. ALC administered after 2VO was not protective, but as pretreatment prior to 2VO it restored LTP nearly to the control level. This finding paralleled the histological analysis: ALC pretreatment resulted in the reappearance of dendritic spines on the CA1 pyramidal cells. Our data demonstrate that ALC administration can restore hippocampal function and spine density. ALC probably acts by enhancing the aerobic metabolic pathway, which is inhibited during and following ischemic attacks.

Obesity and aspirin intolerance are risk factors for difficult-to-treat asthma in Japanese non-atopic women

BACKGROUND

Asthma is a clinical syndrome characterized by variabilities in disease expression and severity. The pathophysiological mechanism underlying anti-asthma treatment resistance is also assumed to be different between disease phenotypes.

OBJECTIVE

To elucidate the effect of gender and atopic phenotype on the relationship between clinical factors and the risk of treatment resistance.

METHODS

We compared outpatients with difficult-to-treat asthma (DTA; n = 486) in a tertiary hospital for allergic diseases in central Japan with those with controlled severe asthma (n = 621) with respect to clinical factors including body mass index (BMI) and aspirin intolerance using multivariate logistic regression analysis stratified by gender and atopic phenotype.

RESULTS

When analysis was performed on the entire study populations, obesity (BMI ≥ 30 kg/m(2); adjusted odds ratio (OR) 1.92; 95% confidence interval (95% CI: 1.07-3.43) and aspirin intolerance (OR: 2.56, 95% CI: 1.44-4.57) were found to be the significant risk factors for DTA. However, after the stratification by gender and atopic phenotype, the association between obesity and DTA was significant only in women (OR: 2.76, 95% CI: 1.31-5.78), but not in men (OR: 1.03, 95% CI: 0.38-2.81), and only in non-atopics (OR: 4.03, 95% CI: 1.15-14.08), but not in atopics (OR: 1.54, 95% CI: 0.79-3.02). The similar gender and phenotypic differences were also observed in the association between aspirin intolerance and DTA: namely, the association was significant only in women (OR: 3.96, 95% CI: 1.84-8.50), but not in men (OR: 1.19, 95% CI: 0.46-3.05); and only in non-atopics (OR: 5.49, 95% CI: 1.98-15.19), but not in atopics (OR: 1.39, 95% CI: 0.65-2.98).

CONCLUSIONS AND CLINICAL RELEVANCE

Significant associations of obesity and aspirin intolerance with DTA were observed only in women and in non-atopics. These findings suggest that a phenotype-specific approach is needed to treat patients with DTA.

Urinary concentrations of 15-epimer of lipoxin A(4) are lower in patients with aspirin-intolerant compared with aspirin-tolerant asthma

BACKGROUND

Although an abnormality in arachidonic acid metabolism may be responsible for aspirin-intolerant asthma (AIA), there is little knowledge about the concentrations of urinary lipoxin A(4) (LXA(4)) and the 15-epimer of LXA(4) (15-epi-LXA(4)) in relation to asthma severity in AIA subjects.

OBJECTIVE

The purpose of this study is to estimate urinary LXA(4) and the 15-epimer concentrations to investigate lipoxins in AIA.

METHODS

In this study, we examined AIA, aspirin-tolerant asthma (ATA) and healthy control groups. The AIA and ATA groups were subdivided into the severe asthma and non-severe asthma subgroups. Urinary LXA(4), 15-epi-LXA(4) and leukotriene E(4) (LTE(4) ) were quantified using enzyme immunoassay after separating these compounds using high-performance liquid chromatography.

RESULTS

The urinary LXA(4) concentration was significantly lower than the 15-epi-LXA(4) concentration in the asthmatic subjects. The AIA group showed significantly lower urinary 15-epi-LXA(4) (P < 0.01) and higher urinary LTE(4) concentrations (P < 0.05) than the ATA group. Comparison of 15-epi-LXA(4) concentrations between the severe asthmatic and non-severe asthmatic subjects in the AIA and ATA groups revealed that the decreased 15-epi-LXA(4) concentration may be related to aspirin intolerance, but not asthma severity. Receiver operator characteristic curves demonstrated that the concentration ratio of LTE(4) to 15-epi-LXA(4) was superior to 15-epi-LXA(4) concentration and LTE(4) concentration as a predictive factor for aspirin intolerance.

CONCLUSIONS AND CLINICAL RELEVANCE

We have demonstrated for the first time that urinary 15-epi-LXA(4) concentration is significantly higher than LXA(4) concentration in both the AIA and ATA groups. 15-Epi-LXA(4) concentration was significantly lower in the AIA group with an increased urinary LTE(4) concentration than in the ATA group. An imbalance between proinflammatory cysteinyl-leukotrienes and anti-inflammatory 15-epi-LXA(4) may be involved in AIA pathogenesis.

Identification of TEM-135 beta-lactamase in penicillinase-producing Neisseria gonorrhoeae strains in Japan

Ten penicillinase-producing Neisseria gonorrhoeae (PPNG) strains isolated from 2000 to 2008 were characterized by multilocus sequence typing, multiantigen sequence typing, and plasmid typing. Sequence analysis showed that 8 strains contained a TEM-1 beta-lactamase gene. However, two other genetically distinct PPNG strains, isolated in 2004 and 2008, each contained a TEM-135 beta-lactamase on different plasmids, a Toronto/Rio type R plasmid and an Asia type R plasmid, suggesting independent origins of these PPNG strains.

The use of frequency scale for the symptoms of GERD in assessment of gastro-oesophageal reflex symptoms in asthma

In adult asthmatics the incidence of gastro-oesophageal reflux disease (GERD) reportedly ranges from 34% to 89%. Oesophageal pH monitoring and endoscopy are not required in the patient with typical GERD symptoms before the initiation of a therapeutic trial. Diagnosis of GERD on the basis of history is the simplest and quickest method, placing no demand on patients. Recently, a new questionnaire (FSSG; Frequency Scale for the Symptoms of GERD) was produced to evaluate the severity and the therapeutic response of GERD. The FSSG (F-scale) was used to assess the GERD in subjects with persistent moderate to severe asthma treated with anti-inflammatory asthma medication. In the present study, 27.4% of the patients with asthma had symptoms suggestive of GERD. There is significant correlation between GERD symptom (F-scale score) and severity of cough and sputum. The observations suggested that reflux symptoms, not gastric dysmotility symptoms, significantly associated with severity of cough, not of sputum. It is the first such study to use a FSSG as incidence of GERD symptoms in asthmatics and examine the relationship between F-scale score and asthmatic symptoms.

Concentration of 14,15-leukotriene C4 (eoxin C4) in bronchoalveolar lavage fluid

BACKGROUND

There has been no information about the concentration of 14,15-leukotriene C4, which is generated by 15- and 12-lipoxygenase and has been recently named eoxin C4, in biological fluids.

OBJECTIVE

To determine the clinical concentrations of eoxin C4 in various respiratory inflammatory diseases, we quantified eoxin C4 in relation to the concentrations of cysteinyl-leukotrienes (CysLTs) and 15-hydroxyeicosatetraenoic acid (15-HETE) in bronchoalveolar lavage fluid (BALF).

METHODS

BALF fluid was obtained from patients with a number of inflammatory lung diseases. Eoxin C4 and CysLTs were quantified by enzyme immunoassay in combination with high-performance liquid chromatography. Eoxin C4 immunoassay does not detect eoxin D4 or eoxin E4. 15-HETE was quantified by gas chromatography-mass spectrometry using (18)O-labeled compounds as an internal standard.

RESULTS

The concentration of eoxin C4 (median 1.4, range <1.12-6.7 pg/mL) was significantly lower than that of eoxin C4 or CysLTs (P<0.0001). The concentration of 15-HETE significantly correlated with those of LTC4 and CysLTs or the number and the percentage of eosinophils in BALF. On the other hand, eoxin C4 concentration did not correlate with eosinophil number or CysLTs concentration in BALF.

CONCLUSIONS

This is the first study demonstrating the presence of eoxin C4 in human biological fluids. Further studies are necessary to elucidate the pathophysiological role of eoxin C4 in some respiratory inflammatory diseases.

Imbalance of naive and memory T lymphocytes with sustained high cellular activation during the first year of life from uninfected children born to HIV-1-infected mothers on HAART

The immune consequences of in utero HIV exposure to uninfected children whose mothers were submitted to highly active antiretroviral therapy (HAART) during gestation are not well defined. We evaluated 45 HIV-exposed uninfected (ENI) neonates and 45 healthy unexposed control (CT) neonates. All HIV-infected mothers received HAART during pregnancy, and the viral load at delivery was <50 copies/mL for 56.8%. Twenty-three ENI neonates were further evaluated after 12 months and compared to 23 unexposed healthy age-matched infants. Immunophenotyping was performed by flow cytometry in cord and peripheral blood. Cord blood lymphocyte numbers did not differ between groups. However, ENI neonates had a lower percentage of naive T cells than CT neonates (CD4+, 76.6 vs 83.1%, P < 0.001; CD8+, 70.9 vs 79.6%, P = 0.003) and higher percentages of central memory T cells than CT neonates (CD4+, 13.9 vs 8.7%, P < 0.001; CD8+, 8.6 vs 4.8%, P = 0.001). CD38 mean fluorescence intensity of T cells was higher in ENI neonates (CD4+, 62.2 vs 52.1, P = 0.007; CD8+, 47.7 vs 35.3, P < 0.001). At 12 months, ENI infants still had higher mean fluorescence intensity of CD38 on T cells (CD4+, 34.2 vs 23.3, P < 0.001; CD8+, 26.8 vs 19.4, P = 0.035). Despite effective maternal virologic control at delivery, HIV-exposed uninfected children were born with lower levels of naive T cells. Immune activation was present at birth and remained until at least 12 months of age, suggesting that in utero exposure to HIV causes subtle immune abnormalities.

uspA1 of Moraxella catarrhalis clinical isolates in Japan and its relationship with adherence to HEp-2 cells

The surface protein, UspA1, of Moraxella catarrhalis is involved in adherence to human epithelial cells. We examined the expression of uspA1, and adherence to HEp-2 cells of clinical isolates. The uspA1 gene was detected in 204 of 208 isolates. The 4 uspA1-negative isolates belonged to the 16S rRNA type II with an A to G substitution at nucleotide 445 of 16S rRNA. In 13 isolates of the 16S rRNA type II, transcription of uspA1 was decreased or absent. A relationship between the extent of uspA1 transcription and adherence to HEp-2 cells was found in 5 isolates of the type I. In contrast, the 16S rRNA type II strains still had considerable adherence to HEp-2 cells. The type I uspA1 gene was expressed in Escherichia coli JM109 and the transformants adhered to HEp-2 cells at rates about 7 times higher than the host strain. These data indicated that the uspA1 was virtually ubiquitous in clinical isolates of M. catarrhalis and was responsible for adherence to HEp-2 cells of 16S rRNA type I isolates. However, the data also suggested that adherence of 16S rRNA type II strains to HEp-2 cells was attributed to factor(s) other than UspA1.

Increased production of cysteinyl leukotrienes and prostaglandin D2 during human anaphylaxis

BACKGROUND

Anaphylaxis is a life-threatening syndrome resulting from the sudden release of mast cell- and basophil-derived mediators into the circulation. However, pathological evidence of the association between inflammatory mediators and human anaphylaxis is insufficient.

OBJECTIVE

The aim of this study was to better understand the relationship between in vivo production of inflammatory mediators and the pathogenesis of anaphylaxis. We also sought to evaluate mast cell activation in anaphylaxis.

METHODS

We measured the concentrations of various inflammatory mediators in urine samples, which were collected from 32 anaphylactic patients during the onset of anaphylaxis and during clinical remission, 21 patients with asthma on acute exacerbation and 15 healthy control subjects. Blood and urine specimens were collected from the patients after provocation test. Urinary leukotriene E4 (LTE4), 9alpha, 11beta-prostaglandin F2 (9alpha, 11beta-PGF2), eosinophil-derived neurotoxin (EDN) and leukotriene B4 glucuronide (LTBG) concentrations were determined by enzyme immunoassay, and the activity of plasma platelet-activating factor acetylhydrolase and serum tryptase concentration were measured using commercially available kits.

RESULTS

Significantly higher concentrations of urinary LTE4 and 9alpha, 11beta-PGF2, which immediately decreased during clinical remission, were observed in the anaphylactic patients than in asthmatic patients on acute exacerbation and healthy control subjects. Concentrations of EDN and LTBG were not significantly different among the anaphylactic patients, asthmatic patients on acute exacerbation and healthy subjects. There was a significant correlation between urinary LTE4 and 9alpha, 11beta-PGF2 concentrations in the anaphylactic patients (r=0.672, P=0.005, n=32). In addition, LTE4 concentration in patients with anaphylactic shock is significantly elevated compared with that in patients without anaphylactic shock.

CONCLUSIONS

This is a report on the significant increase in urinary LTE4 and 9alpha, 11beta-PGF2 concentrations during anaphylaxis. Urinary LTE4 and 9alpha, 11beta-PGF2 concentrations may be a reliable marker of endogenous production of inflammatory mediators associated with anaphylaxis.

Effect of Fusarium verticillioides extract on specific antibody production against Paracoccidioides brasiliensis

The aim of this study was to evaluate the effect of partially purified Fusarium verticillioides fumonisins (FB) on the specific humoral response in mice infected with Paracoccidioides brasiliensis (Pb), the agent of paracoccidioidomycosis (PCM). Four groups of male Swiss mice were used (total 44 mice): infected (Pb), treated (FB), infected and treated (Pb/FB) and uninfected and untreated (PBS). Groups Pb and Pb/FB were inoculated i.v. with 1x105 Pb yeast cells (strain Pb18) and, after 28 days, groups FB and Pb/FB were inoculated (s.c.) with partially purified FB from F. verticillioides (5x2.25 mg FB/kg body weight). After 7 days, the plasma levels of total IgG and anti-gp43 IgG (specific antibody) were analysed by immunoenzyme assay (ELISA). The total IgG level was higher in groups Pb, FB and Pb/FB than in PBS (P<0.05) and the anti-gp43 IgG level was raised in groups Pb and Pb/FB, but a significant result was obtained only in Pb/FB, relative to the other groups (P<0.05). In conclusion, FB or other components of F. verticillioides extracts significantly increase the specific antibody response in male Swiss mice infected with Pb.

Implication of pre-drying steps with natural fumonisin contamination levels in freshly harvested corn

Maize quality regarding fumonisin contamination of 390 freshly harvested samples used by maize processing industries in the Northern region of Parana State, Brazil (2003 crop) was evaluated and correlated to the time elapsed from harvesting to the pre-drying step. Sampling was carried out at three points of the maize production chain, immediately after harvesting (n=100), at the industry delivery posts (n=200) and before the drying process (n=90). Fumonisin B1 (FB1) was detected in all the samples from the three points of the maize production chain. FB1 levels ranged from 0.11 to 12.68 µg/g (mean 1.81±2.12 µg/g) in the field samples, 0.10 to 11.83 µg/g (mean 1.83±1.75 µg/g) in the reception samples and from 0.02 to 10.98 µg/g (mean 2.31±2.38 µg/g) in the pre-drying samples. FB2 levels ranged from 0.01 to 5.26 µg/g (mean 0.84±0.94 µg/g) in the field samples, from 0.02 to 5.25 µg/g (mean 0.74±0.69 µg/g) in the reception samples and from 0.07 to 7.89 µg/g (mean 1.25±1.29 µg/g) in the pre-drying samples. Although there was no significant difference in mean fumonisin levels among the field, reception and pre-drying samples by the Tukey multiple comparison test (P<0.05), there was a positive correlation (P<0.05) between fumonisin levels and the time elapsed (p=0.95) from harvesting to the pre-drying step. Therefore reduction in the harvest/drying interval would be essential to assure product quality and safety and minimise potential health hazards.

Increased urinary leukotriene E4 concentration in patients with eosinophilic pneumonia

Although eosinophils produce cysteinyl leukotrienes (CysLTs) in large quantities, information on the relationship between CysLTs and eosinophilic pneumonia (EP) is lacking. Inflammatory mediator concentrations in urine were quantified to clarify the relationship between CysLT concentrations and EP severity. Leukotriene (LT)E(4), eosinophil-derived neurotoxin (EDN), 9alpha,11beta-prostaglandin F2 and LTB(4) glucuronide concentrations were quantified in the urine of: EP patients during acute exacerbation and clinical remission; asthmatic patients during acute exacerbation and under stable conditions; and healthy control subjects. The urinary LTE(4) and EDN concentrations of EP patients during acute exacerbation were significantly higher than those of asthmatic patients and healthy subjects, and decreased immediately during clinical remission. The urinary LTE(4) concentration was associated with the urinary EDN concentration of EP patients during acute exacerbation. The urinary LTE(4) concentration significantly correlated with the diffusing capacity of the lung for carbon monoxide in EP patients during acute exacerbation. The increased urinary concentrations of leukotriene and eosinophil-derived neurotoxin were associated with acute exacerbation in eosinophilic pneumonia patients. The increased leukotriene concentration significantly correlated with diffusing capacity of the lung for carbon monoxide, suggesting that the monitoring of leukotriene concentration may aid in the management of eosinophilic pneumonia patients.

Multicenter study to evaluate bloodstream infection by Helicobacter cinaedi in Japan

Helicobacter cinaedi has being recognized as an important human pathogen which causes bloodstream infections. Although the first case of bacteremia with this pathogen in Japan was reported in 2003, the true prevalence of H. cinaedi as a pathogen of bloodstream infections in this country is not yet known. Therefore, the aim of our study was to assess the incidence of bacteremia with H. cinaedi in Japan. We conducted a prospective, multicenter analysis in 13 hospitals during 6 months in Tokyo, Japan. Among positive blood cultures from 1 October 2003 to 31 March 2004, isolates suspected of being Helicobacter species were studied for further microbial identification. Identification of the organisms was based on their biochemical traits and the results of molecular analysis of their 16S rRNA gene sequences. A total of 16,743 blood culture samples were obtained during the study period, and 2,718 samples (17.7%) yielded positive culture results for coagulase-negative staphylococci. Among nine isolates suspected to be Helicobacter species, six isolates were finally identified as H. cinaedi. The positivity rate for H. cinaedi in blood culture was 0.06% of total blood samples and 0.22% of blood samples with any positive culture results. All patients with bacteremia with H. cinaedi were found to have no human immunodeficiency virus (HIV) infection, but many of them had complications with either malignancy, renal failure, or a history of surgical operation. Therefore, our results suggest that bacteremia with H. cinaedi is rare but can occur in compromised hosts other than those with HIV infection in Japan.

Nested polymerase chain reaction for detection of the avian leukosis virus causing so-called fowl glioma

The complete nucleotide sequence of the avian leukosis virus causing so-called fowl glioma has been previously determined. Primers were designed for detection of the fowl glioma-causal virus (FGV) based on the 3' untranslated region of the viral genome. The provirus and viral RNA of FGV were specifically detected in various organs and tissues, including feather pulp, from experimentally infected birds using nested polymerase chain reaction (PCR) and reverse transcription nested PCR. The prevalence of FGV was evaluated in 131 Japanese fowls of a zoological garden in Japan based on the detection of the FGV genome in feather pulp using PCR and the detection of viral antigen in faeces by enzyme-linked immunosorbent assay. FGV proviral DNA was detected in feather pulp of 52 birds (39.7%) by nested PCR. Later, nine dead birds from among the 52 were histologically diagnosed as having fowl glioma and found to have the proviral DNA in the affected brain. These results demonstrated that the PCR-based detection of FGV in feather pulp is useful for epidemiological studies on fowl glioma.

The first immunoglobulin-like domain of porcine nectin-1 is sufficient to confer resistance to pseudorabies virus infection in transgenic mice

Nectin-1 is an alphaherpesvirus receptor that binds to virion glycoprotein D (gD). Porcine nectin-1 mediates entry of pseudorabies virus (PRV), herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), and bovine herpesvirus type 1 (BHV-1). The gD-binding domain of nectin-1 is the first or N-terminal immunoglobulin (Ig)-like domain of the entire ectodomain. Here, we generated three transgenic mouse lines expressing a fusion protein consisting of the first Ig-like domain of porcine nectin-1 and the Fc portion of porcine IgG1 to assess the antiviral potential of the first Ig-like domain of nectin-1 in vivo. All of the transgenic mouse lines showed significant resistance to PRV infection via intraperitoneal inoculation (survival rates of 67% to 100%). In the intranasal challenge, a lower but still significant protection was observed; 21% to 55% of the animals from the three transgenic mouse lines survived. The present results demonstrate that a soluble form of the first domain of porcine nectin-1 is able to exert a significant antiviral effect against pseudorabies virus infection.

Immunogenicity and Tolerability of Hepatitis A Vaccine in HIV-Infected Children

The immunogenicity and tolerability of hepatitis A virus vaccine was evaluated in a group of 32 children with human immunodeficiency virus (HIV) infection and 27 children with seroreversion. After 2 doses of vaccine, 100% of children experienced seroconversion with good toleration of the vaccine. There were no differences in variation of virus load between immunized HIV-positive children and a group of 31 nonimmunized HIV-positive children with similar characteristics.

Moraxella catarrhalisDoes Not Grow on Nutrient Agar without Sodium Chloride Supplementation

None of the 58 Moraxella catarrhalis strains grew on nutrient agar without sodium chloride supplementation, whereas 49 of 51 commensal Neisseria spp. strains tested did. Growth on nutrient agar without sodium chloride supplementation could be used for screening between M. catarrhalis and commensal Neisseria spp.

Genome sequence analysis of the avian retrovirus causing so-called fowl glioma and the promoter activity of the long terminal repeat

So-called fowl glioma is a retroviral infectious disease caused by avian leukosis virus subgroup A (ALV-A). We determined the complete nucleotide sequence of the virus genome. The full-length sequence was consistent with a genetic organization typical of a replication-competent type C retrovirus lacking viral oncogenes. The coding sequences were well conserved with those of replication-competent viruses, but the 3' noncoding regions including LTR were most related to those of replication-defective sarcoma viruses. The U3 region of the LTR had a few deletions and several point mutations compared to that of other ALVs. The promoter activities of the LTRs of glioma-inducing ALV and ALV-A standard strain, RAV-1, were equivalent in chick embryo fibroblasts (CEF), while that of glioma-inducing ALV was significantly lower than that of RAV-1 in human astrocytic cells. These subtle differences of the promoter activity of the LTR may be related to the induction of glial neoplasm.

Varicella zoster antibodies in healthcare workers from two neonatal units in São Paulo, Brazil—assessment of a staff varicella policy

Although frequently reported in the literature, a staff varicella policy is not standard in many hospitals even in developed countries. In the present study, we assessed varicella zoster immunity in staff from two neonatal units from hospitals in São Paulo, Brazil. Ninety-seven percent of all staff working in both units agreed to participate. A simple and cost-effective varicella policy was subsequently set up, based on costs and data from serology and a history of previous varicella infection. Our results confirm that a varicella vaccination programme can be implemented in a healthcare facility, even in developing countries.

Isolation of Helicobacter cinaedi from blood of an immunocompromised patient in Japan

We report the isolation of Helicobacter cinaedi (previously called " Campylobacter-like organism") from the blood of an immunosuppressed Japanese patient receiving immunosuppressive therapy after renal transplantation. The identification of H. cinaedi was based on the findings of microscopic examinations, biochemical properties, and 16S rRNA gene nucleotide sequences. H. cinaedi bacteremia should be considered as one of the critical infectious diseases in immunocompromised patients, and the sequencing of 16S rRNA may be a useful method to confirm the identification of this organism.

The pseudorabies virus immediate-early promoter directs neuronal tissue-specific expression in transgenic mice

Pseudorabies virus (PRV) immediate-early (IE) gene product is required for expression of the viral early and late genes as a transactivator. The IE gene is expressed as the first gene among the viral genes after the infection. To examine the activity of the IE promoter in vivo, we have generated transgenic mice expressing transgenes under the control of the IE promoter. To analyze the tissue specificity of the transgene expression, mRNA of the transgene was monitored in various tissues from the transgenic mice by reverse transcriptase (RT)-polymerase chain reaction (PCR) analysis. A strong transgene expression was observed in the neuronal tissues by the RT-PCR analysis. These neuronal tissues included cerebrum, cerebellum and trigeminal nerve. Although the PCR product was hardly detected in other tissues by the RT-PCR analysis, specific PCR bands were detected in multiple organs (skin, skeletal muscles, heart muscles, lung, liver, spleen, small intestine and kidney) by Southern blot analysis using the RT-PCR products. These results indicate that although the IE promoter acts as a pan-specific promoter in vivo, it is capable of driving a high level of transgene expression in neuronal tissues.

Evaluation of light transmission and distribution materials for Lunar and Martian bioregenerative life support

The materials that were selected and evaluated in this study in the context of bioregenerative advanced life support included polymer optical cables, for transmission of photosynthetic photon flux (PPF), and light pipe, woven optical pad and light-emitting fiber (LEF) for PPF distribution. All materials exhibited significant fidelity in transmitting the spectral characteristics of the artificial lluminator's Xenon-Metal Halide lamp. The PPF attenuation values for the polymer cables EL-200, EL-300, EL-400, and EL-500 were not significantly distinguishable from one another nor from that of the fused-silica cable of 0.34 dB/m. With the exception of EL-100 and EL-700, which had significantly lower PPF transmission efficiencies of 54.9%/m and 66.6%/m, respectively, all the other polymer cables had PPF transmission efficiencies of over 85%/m which, except for EL-300, were not significantly different from one another nor from that of the fused-silica cable of 93.2%/m. The highest PPF output efficiency achieved for the 7.1-cm light pipe 14.7%, for its maximum pipe length of 100 cm. At a constant pipe length of 50 cm, the PPF output efficiency of the 10-cm light pipe of 0.71% was significantly lower than that of the 7.1-cm light pipe of 10.54%. The PPF output for the woven optical pad was determined to be 36.3%. The PPF output efficiency for the LEF without the optic fastener was determined to be 27.1%, whereas that for the LEF with the optic fastener was 50.3%, that is, the maximum value of PPF output efficiency in the study. The polymer optical cables, light pipe, woven optical pad, and LEF exhibited significant regularity and symmetry in their PPF output spatial distributions.

Characterizations of high-intensity red and blue light-emitting diodes (LEDs) as a light source for plant growth

Recently developed high-intensity red and blue light-emitting diodes (LEDs), which constitute a potentially improved light source for controlled-environment plant growth applications such as in vitro micropropagation and biologically based advanced life support (ALS) for space missions, were characterized in this study. Blue 2 LED and Red 1 LED consistently yielded the highest and lowest voltage drop readings, respectively, for all the electrical current settings tested (5-50 mA), with Blue 1 LED producing voltage drops falling nearly in the middle of the readings for the first two LEDs. At the standard current setting of 20 mA, Blue 2 LED and Blue 1 LED required 2.5 and 1.6 times more electrical power, respectively, than did Red 1 LED. At the standard current of 20 mA, the average photosynthetic photon flux (PPF) for Red 1 LED, Blue 1 LED, and Blue 2 LED were 180, 145, and 36 micromoles m-2 s-1, respectively. Red 1 LED peaked at 460 micromoles m-2 s-1 at 50 mA, Blue 1 LED at 200 micromoles m-2 s-1 at 40 mA, and Blue 2 LED at 40 micromoles m-2 s-1 at about 25 mA. For all current settings, the electrical conversion efficiency of Red 1 was approximately two times greater than that of Blue 1 LED. The electrical conversion efficiency of Blue 1 and of Red 1 LED peaked in between 10 and 20 mA, at about 13 mA for Blue 1 LED and at about 15 mA for Red 1 LED. The normalized PPF distributions for both Red 1 LED and Blue 1 LED were independent of the various magnitudes of electrical current (20, 30, 40, and 50 mA) that were applied to the LEDs.

A pan-specific promoter activity of the 213bp segment of the pseudorabies virus early protein 0 gene in transgenic mice

Pseudorabies virus (PrV) early protein 0 (EP0) is a transactivator that plays important roles in the viral gene expression. To examine a promoter regulatory element for the EP0 gene expression in vivo, we have generated two transgenic mouse lines expressing the EP0 gene under the control of a 213bp 5'-flanking sequence of the EP0 gene. To analyze the tissue specificity of transgene expression, mRNA of the EP0 gene was monitored in various tissues from the transgenic mice by the reverse transcriptase (RT)-polymerase chain reaction (PCR) analysis. The EP0 gene expression was demonstrated in all tissues tested by the RT-PCR analysis. These tissues included skin, muscles (skeletal and heart), lung, liver, spleen, small intestine, kidney, brain and testis. These results indicated that the 213bp sequence of the 5'-flanking region of the EP0 gene is capable of driving expression of the EP0 gene in vivo and the promoter is pan-specific.

Design parameters of flat-panel LED modules for plant lighting applications

Semispherical high-intensity light-emitting diodes (LEDS) mounted on a circuit board have been developed and examined for plant growth applications. This type of LED configuration, however, has problems such as relatively poor heat dissipation, difficulty of effecting high light uniformity, and high cost of assembly. Such problems may now be obviated through use of the recently developed flat-panel LED modules. In this study, the photosynthetic photon flux (PPF) levels and PPF distribution of 172 x 27 mm red flat-panel LED modules were determined. Results showed that: 1) the red flat-panel LED modules tested produced a mean PPF level of about 111 micromoles m-2 s-1 at a distance of 10 cm, which would be adequate for most micropropagated species grown photomixotrophically and reasonable for some micropropagated species grown photoautotrophically, both in terms of red wavelength; 2) the mean surface PPF of 419 micromoles m-2 s-1 for a single LED in a flat-panel module was about 47% greater than that for a single semispherical LED at about equal operational currents, owing primarily to the significantly larger reflectance area present in a flat-panel LED than that in a semispherical LED; 3) two flat-panel LED modules tested had about 80% of their illuminated areas having PPF values equal to or greater than half their maximum PPF levels, whereas the third module had a corresponding figure of about 67%; and 4) flat-panel LED modules exhibited very similar PPF distributions, underscoring the advantage of the LED flat-panel design over the manually assembled LED array in the ease of replicating light distributions.