The Incidence of Severe Radiation-Induced Lymphopenia during Chemoradiotherapy for Stage Ⅲ Non-Small Cell Lung Cancer: A Comparative Study of Proton Versus Photon-Based Radiotherapy

PURPOSE/OBJECTIVE(S)

To investigate the incidence of severe radiation-induced lymphopenia (SRL) and the survival in patients with stage Ⅲ non-small cell lung cancer treated with concurrent chemoradiotherapy with passive scattering proton beam (PSPT) or photon-based radiotherapy (XRT) including 3D-CRT and IMRT.

MATERIALS/METHODS

We conducted a retrospective cohort study including 355 patients who received definitive concurrent chemoradiotherapy with PSPT (n = 38) or XRT (n = 317) at our institution between January 2010 and December 2020. SRL during concurrent chemoradiotherapy was defined as absolute lymphocyte counts (ALCs) of <500 cells/mm3. Propensity score matching (PSM) analysis was performed to adjust for the patient characteristics between the PSPT and XRT groups. Propensity scores were calculated using age, sex, PS (0-1 vs. 2), primary tumor location (upper/middle vs. lower lobe), pathology (Adeno vs. Others), PTV volume, ALCs at pretreatment, year of treatment (before vs. after July 2018, when durvalumab approved in Japan), and platinum-based chemotherapy regimen (CDDP based vs. CBDCA based). After PSM, the incidence of SRL and the overall survival (OS) were analyzed.

RESULTS

The GTV and PTV volumes were significantly lower in the PSPT group than in the XRT group (median, 57 vs. 103 mm3; p < 0.05, 322 vs. 399 mm3; p < 0.05, respectively). ALCs at pretreatment were significantly lower in the PSPT group than in the XRT group (median, 1531 vs. 1718 cells/mm3; p < 0.05). SRL was observed in 275 patients (87%) in the XRT group and 27 patients (71%) in the PSPT group (p < 0.05). After PSM, PSPT significantly reduced the incidence of SRL compared to XRT (68.6 % vs. 88.6 %, p < 0.05), and the patients without SRL may have better 3-year OS than those with SRL (71.1 % vs. 55.3 %; p = 0.062).

CONCLUSION

Compared with XRT, PSPT significantly reduced the incidence of SRL, and the patients without SRL had a good prognosis.

Dosimetric Evaluation of Targets and Organs at Risk in Dose Escalation Study for Total Marrow and Lymphoid Irradiation

PURPOSE/OBJECTIVE(S)

Total marrow and lymphoid irradiation (TMLI) delivers radiation dose to the bone marrow and lymph nodal region while reducing the dose to non-target organs. We conducted a dose-escalation study of TMLI to improve treatment outcomes while reducing OAR doses using intensity-modulated radiation therapy. However, this dose escalation strategy may cause increasing risk of recurrence and adverse events because of dose uniformity compromises of the target. We hypothesized that the homogeneity index (HI) could become worse with increased target's dose while maintaining reduced OAR doses for the nine patients enrolled in the TMLI phase Ⅰ clinical trial.

MATERIALS/METHODS

Nine patients treated with TMLI using a treatment delivery system from September 2019 to August 2021 were included. The prescribed doses were 14 Gy/6 fr, 16 Gy/6 fr, and 18 Gy/6 fr twice daily for 3 days, with three patients allocated each prescription. Bone marrow, lymph nodal region, spleen, testis, brain, and liver were designated as targets. The bone marrow was divided into eight parts (see Table); an individual PTV margin was added to each structure. We intended to deliver the D80% prescription dose for PTV. For the brain and liver, the prescribed dose was 12 Gy in consideration of function preservation. Lenses, oral cavity, parotid glands, lungs, heart, esophagus, stomach, kidneys, intestines, and breasts were defined as OAR. Targets were evaluated with HI that was calculated using the formula HI = (D2%-D98%)/D50%, based on ICRU report 83. For OARs, Dmax, D2%, D10%, and mean dose constraint were evaluated.

RESULTS

The table lists HI for the PTV_ALL and each target. The HI of PTV_ALL rose with increasing prescription dose and was highest at 18 Gy. The highest HI was 0.632 for PTV_Rib at 18 Gy, and the lowest HI was 0.045 for PTV_testis at 14 Gy. OAR Dose constraints were achieved in all patients. The average OAR doses in all cases for lenses, oral cavity, parotid glands, lungs, heart, esophagus, intestines, kidneys, and breast were 4.7±0.80, 4.4±0.51, 6.7±0.48, 7.6±0.22, 7.8±0.19, 6.7±0.18, 7.4±1.12, 6.9±0.96, and 14.7 Gy, respectively. The Dmax of the lenes, D2% of the esophagus, and D10% of the stomach were 7.2 ± 1.09, 11.5 ± 0.47, and 10.9 ± 0.98 Gy, respectively.

CONCLUSION

In the TMLI phase I clinical trial, we evaluated the dose uniformity to the targets and the OAR dose constraints. Although the HI for PTV_ALL worsened with increasing prescription dose, compliance with OAR dose constraints was achieved in all patients.

Mast cell hyperactivity underpins the development of oxygen-induced retinopathy

Mast cells are classically thought to play an important role in protection against helminth infections and in the induction of allergic diseases; however, recent studies indicate that these cells also contribute to neovascularization, which is critical for tissue remodeling, chronic inflammation, and carcinogenesis. Here, we demonstrate that mast cells are essential for sprouting angiogenesis in a murine model of oxygen-induced retinopathy (OIR). Although mouse strains lacking mast cells did not exhibit retinal neovascularization following hypoxia, these mice developed OIR following infusion of mast cells or after injection of mast cell tryptase (MCT). Relative hypoxia stimulated mast cell degranulation via transient receptor potential ankyrin 1. Subsequent surges in MCT stimulated retinal endothelial cells to produce monocyte chemotactic protein-1 (MCP1) and angiogenic factors, leading to sprouting angiogenesis. Mast cell stabilizers as well as specific tryptase and MCP1 inhibitors prevented the development of OIR in WT mice. Preterm infants with early retinopathy of prematurity had markedly higher plasma MCT levels than age-matched infants without disease, suggesting mast cells contribute to human disease. Together, these results suggest therapies that suppress mast cell activity should be further explored as a potential option for preventing eye diseases and subsequent blindness induced by neovascularization.

Clinical utility of the basophil activation test for analysis of allergic transfusion reactions: a pilot study

BACKGROUND AND OBJECTIVES

In previous studies, we demonstrated that the basophil-activating effects of supernatants found in residual-transfused platelet concentrates (PC-SNs) on whole blood basophils in cases of allergic transfusion reactions (ATRs) could be assessed by the basophil activation test (BAT) in terms of allergen/IgE dependency. However, in these studies, the basophils were derived from third-party healthy volunteers. In this study, we performed BAT using patients' own blood basophils to analyse ATRs.

MATERIALS AND METHODS

The BAT was performed in two cases of severe ATRs using residual PC-SNs and the patients' own basophils in the presence and absence of dasatinib, an inhibitor of IgE-mediated basophil activation.

RESULTS

In both cases, PC-SNs exhibited basophil-activating activity against the patients' basophils, but not against basophils from third-party healthy volunteers. In addition, basophil activation was inhibited in the presence of dasatinib, indicating that the basophils were activated in an allergen/IgE-dependent manner. Of note, the basophils in Case 2, but not in Case 1, were activated by PC-SNs from some unrelated non-haemolytic transfusion reaction cases.

CONCLUSION

This pilot study indicates that the BAT may be useful in clarifying the causal relationship between ATRs and transfused blood as well as in elucidating the mechanisms behind ATRs considering the allergen/IgE-dependent pathway.

Sorafenib plus hepatic arterial infusion chemotherapy with cisplatin versus sorafenib for advanced hepatocellular carcinoma: randomized phase II trial

In a randomized phase II study of sorafenib plus hepatic arterial infusion chemotherapy with cisplatin in comparison with sorafenib alone in patients with advanced hepatocellular carcinoma, it yielded favorable overall survival when compared with sorafenib alone. This is the first report of its effectiveness in relation to the overall survival in comparison with that of sorafenib alone in patients with advanced hepatocellular carcinoma.

Background

Sorafenib (Sor) is acknowledged as a standard therapy for advanced hepatocellular carcinoma (HCC). This trial was conducted to evaluate the effect of addition of hepatic arterial infusion chemotherapy with cisplatin (SorCDDP) to Sor for the treatment of advanced HCC.

Patients and methods

We conducted a multicenter open-labeled randomized phase II trial in chemo-naïve patients with advanced HCC with Child-Pugh scores of 5–7. Eligible patients were randomly assigned 2:1 to receive SorCDDP (sorafenib: 400 mg bid; cisplatin: 65 mg/m², day 1, every 4–6 weeks) or Sor (400 mg bid). The primary end point was overall survival.

Results

A total of 108 patients were randomized (Sor, n = 42; SorCDDP, n = 66). The median survival in the Sor and SorCDDP arms were 8.7 and 10.6 months, respectively [stratified hazard ratio (95% confidence interval), 0.60 (0.38–0.96), P = 0.031]. The median time to progression and the response rate were, respectively, 2.8 months and 7.3% in the Sor arm and 3.1 months and 21.7% in the SorCDDP arm. The adverse events were more frequent in the SorCDDP arm than in the Sor arm, but well-tolerated.

Conclusion

SorCDDP yielded favorable overall survival when compared with Sor in patients with advanced HCC.

Clinical Trial registration

UMIN-CTR (http://www.umin.ac.jp/ctr/index-j.htm), identification number: UMIN000005703.

Preoperative Embolization for Meningioma Using Lipiodol

Four patient (3 males, 1 female) with meningioma treated by preoperative embolization using lipiodol since January 1997 were included in this study. Almost the same procedure was performed on them; superselective catheterization into feeders from the external carotid artery, slow infusion of lipiodol, and proximal occlusion with liquid coils. Duration between embolization and direct surgery varied (5–13 days). Three meningiomas resected 5 days after the embolization were successful but one resected after 13 days needed transfusion. Post operative complications were seen in two patients, one is lockjaw due to ischaemia of the temporal muscles, and the other is transient dilatation of perifocal oedema. The ischaemic effect and safety of lipiodol as embolic material are discussed.

Combination of Sonodynamic and Photodynamic Therapy against Cancer Would Be Effective through Using a Regulated Size of Nanoparticles

Nanoparticles have been used for many functional materials in nano-sciences and photo-catalyzing surface chemistry. The titanium oxide nanoparticles will be useful for the treatment of tumor by laser and/or ultrasound as the sensitizers in nano-medicine. We have studied the combination therapy of photo- and sono-dynamic therapies in an animal tumor model. Oral-administration of two sensitizers titanium oxide, 0.2%-TiO2 nanoparticles for sono-dynamic and 1 mM 5-aminolevulinic acid for photodynamic therapies have resulted in the best combination therapeutic effects for the cancer treatment. Our light microscopic and Raman spectroscopic studies revealed that the titanium nanoparticles were distributed inside the blood vessel of the cancer tissue (1-3 μm sizes). Among these nanoparticles with a broad size distribution, only particular-sized particles could penetrate through the blood vessel of the cancer tissue, while other particles may only exhibit the side effects in the model mouse. Therefore, it may be necessary to separate the optimum size particles. For this purpose we have separated TiO2 nanoparticles by countercurrent chromatography with a flat coiled column (1.6 mm ID) immersed in an ultrasonic bath (42 KHz). Separation was performed with a two-phase solvent system composed of 1-butanol-acetic acid-water at a volume ratio of 4:1:5 at a flow rate of 0.1 ml/min. Countercurrent chromatographic separation yielded fractions containing particle aggregates at 31 and 4400 nm in diameter.

Comparison of neutralization profiles for anti-HCV reactive donor samples with or without detectable HCV RNA

BACKGROUND AND OBJECTIVES

At Japanese Red Cross (JRC) Blood Centers, all donated blood is screened for hepatitis C virus (HCV) by serological and nucleic acid amplification testing. Donor plasma that tested reactive for anti-HCV by serological test is disqualified even if the donor tests negative for HCV RNA. These test results reflect both true-positive results because of past HCV infection and false-positive results because the cross-reactivity of plasma IgG, which current testing methods are unable to distinguish. To characterize these antibody test results, we examined the neutralizing activity of these plasma samples.

MATERIAL AND METHODS

Donor plasma samples that tested reactive for anti-HCV by serological test but negative for HCV RNA (n = 43) were analysed for determining their neutralizing activities measured by the inhibition of the cellular entry of pseudoparticles harbouring HCV envelope glycoproteins (HCVpp).

RESULTS

Strong and broad neutralizing activities against HCVpp entry similar to the samples that tested reactive for anti-HCV serological test and positive for HCV RNA (considered to be derived from individuals with chronic HCV infection) were observed in three of 43 plasma samples from donors who tested anti-HCV reactive but HCV RNA negative.

CONCLUSION

By examining the neutralizing activities of plasma samples, we identified individuals with a past HCV infection from those in whom we were unable to confirm HCV infection according to the current testing algorithms of JRC, which do not perform anti-HCV confirmatory tests.

The association between risk factors and time of onset for thrombocytopenia in Japanese patients receiving linezolid therapy: a retrospective analysis

WHAT IS KNOWN AND OBJECTIVE

Linezolid (LZD) is an oxazolidinone antibiotic that is active against Gram-positive bacteria including methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci. The major adverse effect related to its use in humans is reversible myelosuppression, which mostly manifests as thrombocytopenia. This retrospective study was conducted to identify risk factors that might contribute towards the development of thrombocytopenia due to intravenous administration of LZD.

METHOD

Patients who were administered LZD between January 2008 and March 2013 were included. Thrombocytopenia was defined as a decrease in platelet count of ≥10 × 10(4) cell/μL from baseline or of ≥30%.

RESULTS

A total of 47 patients were included in this study. These patients were divided into two groups: 22 patients (46·8%) were assigned to a non-thrombocytopenia group and 25 patients (53·2%) to a thrombocytopenia group. Multivariate logistic regression analysis revealed significant intergroup differences in duration of LZD treatment [odds ratio (OR) = 1·278; 95% confidence interval (CI) = 1·068-1·529; P = 0·007] and white blood cell (WBC) count (>12000 cells/μL; OR = 10·399; 95% CI = 1·667-64·882; P = 0·012).

WHAT IS NEW AND CONCLUSIONS

This finding suggests that duration of LZD treatment and WBC count (>12000 cells/μL) are risk factors associated with thrombocytopenia resulting from LZD administration.

Studies on expression of aldehyde dehydrogenase in normal and cancerous tissues of thyroids

Recently published articles have reported the controversial data regarding expression of aldehyde dehydrogenase isozyme 1A1 (ALDH1A1), a potential candidate marker for normal and cancer stem cells (CSCs), in thyroid tissues. These data prompted us to re-evaluate expression of ALDH1A1 in normal and cancerous thyroid tissues by 2 different means. The first method was immunohistochemistry with 2 different anti-ALDH1A1 antibodies from distinct companies. Following validating the integrity of these 2 antibodies by Western blotting with ALDH-expressing and nonexpressing cancer cell lines and immunohistochemistry with breast and colon tissues, we report here significant and comparable expression of ALDH1A1 in both normal and cancerous thyroid tissues with both antibodies. Next, relative expression levels of ALDH isozymes were evaluated by reverse transcription-polymerase chain reaction (RT-PCR), revealing that ALDH1A1 was the most highly expressed isozyme followed by ALDH9A1 and relative expression patterns of isozymes were very similar in normal and cancerous tissues. All these data demonstrate that thyroid cells of normal and cancer origins do express ALDH1A1 and to a lesser extent 9A1. Further study will be necessary to study functional significance of ALDH1A1 in the function and behaviors of thyroid normal and cancer stem cells.

Kv1.3 blockers ameliorate allergic contact dermatitis by preferentially suppressing effector memory T cells in a rat model

BACKGROUND

The Kv1.3 voltage-gated potassium channel is selectively upregulated upon activation in effector memory T (TEM ) cells in inflamed tissue, and plays an important role in maintenance of T-cell activation. Although Kv1.3 blockers have been shown to ameliorate allergic contact dermatitis (ACD) in a rat model, it remains unknown whether the effect of Kv1.3 blockers on ACD is mediated by suppressing TEM cell function and/or whether naive T-cells or central memory T (TCM ) cells are influenced.

AIM

To analyse the detailed mechanism of Kv1.3 blockers in a rat model of ACD.

METHODS

We examined the effects of a Kv1.3 blocker on inflammation and production of the effector cytokine interferon (IFN)-γ in inflamed tissue in rat ACD. Single-cell suspensions were isolated from inflamed rat ears (TEM cells), and regional lymph nodes (naive T/TCM cells), and the effect of Kv1.3 blockers on anti-CD3-stimulated IFN-γ production in vitro was measured.

RESULTS

The Kv1.3 blocker significantly suppressed ear inflammation and IFN-γ production at the protein level in vivo. It also suppressed in vitro IFN-γ production from TEM cells from inflamed tissues, but did not suppress the function of naive T/TCM cells from lymph nodes.

CONCLUSIONS

We found that the Kv1.3 blocker ameliorated ACD by inhibiting TEM cell functions only, thus Kv1.3 blockers could be a potentially selective therapeutic agent for TEM cell-mediated inflammatory skin diseases without producing harmful side-effects.

Encephalitis caused by human herpesvirus-6B in pancreas-after-kidney transplantation

Human herpesvirus-6 (HHV-6) is a common pathogen among children, classically presenting with fever and rash that resolves without specific therapy. HHV-6 can be reactivated in the immunosuppressed patient. After bone marrow and solid organ transplantation, HHV-6 has been linked to various clinical syndromes, including undifferentiated febrile illness, encephalitis, myelitis, hepatitis, pneumonitis, and bone marrow suppression. However, HHV-6 encephalitis after pancreatic transplant has rarely been reported. Early diagnosis and treatment of HHV-6 encephalitis may be important for affected patients. We report the case of a 53-year-old pancreas-after-kidney transplant recipient who initially presented with high fever and confusion 3 weeks after operation. We managed to save the patient's life and preserve the pancreas graft function. We also review previously reported cases of HHV-6B encephalitis in solid organ transplant recipients.

FUS immunoreactivity of neuronal and glial intranuclear inclusions in intranuclear inclusion body disease

AIMS

Recent studies have shown that fused-in-sarcoma (FUS) protein is a component of 'neuronal' intranuclear inclusion bodies (INIBs) in the brains of patients with intranuclear inclusion body disease (INIBD). However, the extent and frequency of FUS-immunoreactive structures in INIBD are uncertain.

METHODS

We immunohistochemically examined the brain, spinal cord and peripheral ganglia from five patients with INIBD and five control subjects, using anti-FUS antibodies.

RESULTS

In controls, the nuclei of both neurones and glial cells were intensely immunolabelled with anti-FUS and neuronal cytoplasm was weakly positive for FUS. In INIBD, neuronal and glial INIBs in the brain and spinal cord were positive for FUS. FUS-positive INIBs were also found in the peripheral ganglia. The proportion of FUS-positive neuronal INIBs relative to the total number of inclusion-bearing neurones ranged from 55.6% to 83.3% (average 73.2%) and that of FUS-positive glial INIBs ranged from 45.9% to 85.7% (average 62.7%). The nucleus and cytoplasm of inclusion-bearing neurones and glial cells showed no FUS immunoreactivity.

CONCLUSIONS

These findings suggest that FUS is incorporated into INIBs in both neurones and glial cells and that loss of normal FUS immunoreactivity may result from reduced protein expression and/or sequestration within inclusions.

Expression of hepatocyte growth factor in the skin of amyotrophic lateral sclerosis

OBJECTIVES

Hepatocyte growth factor (HGF) is one of the most potent survival-promoting factors for motor neurons. Overexpression of neuronal HGF has been shown to result in the attenuation of neuronal cell death and progression of disease in a familial amyotrophic lateral sclerosis (ALS) transgenic mouse model. HGF might be beneficial for motor neuron survival and is a good candidate agent for the treatment of ALS. So far, studies of the skin of ALS have shown unique pathological and biochemical abnormalities. However, there has been no study of HGF in ALS skin.

MATERIALS AND METHODS

We made a quantitative immunohistochemical study of the expression of HGF in the skin from 19 patients with sporadic ALS and 16 controls.

RESULTS

Hepatocyte growth factor immunoreactivity was positive in the epidermis, some dermal blood vessels, and glands in patients with ALS. These findings became more conspicuous as ALS progressed. The optical density for HGF immunoreactivity of the nucleus and the cytoplasm in the epidermis in ALS was significantly higher (P < 0.001 and P < 0.001) than in controls. There was a significant positive relation (r = 0.53, P < 0.02 and r = 0.73, P < 0.001) between HGF immunoreactivity and duration of illness in the nucleus and the cytoplasm in the epidermis in patients with ALS.

CONCLUSIONS

These findings suggest that changes in HGF in ALS skin are related to the disease process and that metabolic alterations of HGF may take place in the skin of patients with ALS.

A standardized immunofluorescence test method with human neutrophil antigen-expressing cell lines to enhance antibody detection

There is an international need for a large-scale human neutrophils antigen (HNA) antibody screening platform to minimize the risk of antibody-mediated transfusion-related acute lung injury. However, sourcing a substantial, reliable source of HNA, as well as the scarcity of well-characterized HNA antisera for validating new screening platforms, remain as major obstacles. This short communication presents an improved protocol for the effective use of HNA-expressing KY cells as a screening platform using eight well-characterized HNA antisera of a single defined specificity.

Establishment of a cell line panel as an alternative source of platelet antigens for a screening assay of anti-human platelet antibodies

BACKGROUND

A panel of platelets expressing various human platelet antigens (HPAs) for a platelet antibody screening assay is difficult to prepare because some antigens are rarely expressed. Therefore, an alternative method without using platelets would be helpful in detecting HPA antibodies. This study describes the establishment of cell lines that stably express specific HPAs and their application for detecting specific antibodies.

METHODS

Wild-type β3, HPA-1b, -6b, -7b and -7 variant cDNA as well as wild-type αIIb and HPA-3b cDNA were individually co-transduced with wild-type αIIb and β3 cDNA in the K562 cell line. We performed an immunobead monoclonal antibody immobilisation of platelet antigens (MAIPA) assay to evaluate this cell line panel for antibody detection using identified sera containing HPA antibodies, whose specificities had been determined by the mixed passive haemagglutination test.

RESULTS AND CONCLUSION

Of the 12 sera containing HPA-1a (n = 2), HPA-3a (n = 6), HPA-6b (n = 3) or HPA-7 variant (n = 1) antibodies, all antibodies were detected and determined by our new method, except for two HPA-3a antibodies. One of the two antibodies was also negative for conventional platelet MAIPA, suggesting that the cell line panel might be used as an alternative source of platelet antigens in the MAIPA assay.

Increased expression of TDP-43 in the skin of amyotrophic lateral sclerosis

OBJECTIVES

Transactivation-responsive DNA-binding protein-43 (TDP-43) was identified as a major component of the ubiquitin-positive inclusions in sporadic amyotrophic lateral sclerosis (ALS). However, there has been no study of TDP-43 in ALS skin. The present study investigates TDP-43 in ALS skin.

MATERIALS AND METHODS

We made a quantitative immunohistochemical study of the expression of TDP-43 in the skin from 15 patients with ALS and 15 control subjects.

RESULTS

The proportion of TDP-43-positive (TDP-43+) cells in the epidermis in ALS patients was significantly higher (P < 0.001) than in controls. There was a significant positive relationship (r = 0.62, P < 0.02) between the proportion and duration of illness in ALS patients. The optical density of TDP-43+ cells in the epidermis in ALS patients is markedly stronger (P < 0.001) than in controls. There was a significant positive relation (r = 0.72, P < 0.01) between the immunoreactivity and duration of illness in ALS patients.

CONCLUSIONS

These data suggest that changes of TDP-43 in ALS skin are likely to be related to the disease process and that metabolic alterations of TDP-43 may take place in the skin of patients with ALS.

Theophylline inhibits the differentiation of human monocyte into dendritic cell potentially via adenosine receptor antagonism

BACKGROUND

Theophylline has an anti-inflammatory action that may account for its clinical effectiveness in the reduction of inflammatory cells in the airways. Dendritic cells (DCs) are professional antigen-presenting cells, capable of priming naïve T cells, and play key roles in the activation of immune responses in asthma.

OBJECTIVE

The purpose of this study was to investigate the effects of theophylline on human monocyte differentiation into DCs and whether this involved antagonism of adenosine receptors.

METHODS

Peripheral human blood monocytes were cultured in the presence of granulocyte/macrophage-colony stimulating factor and IL-4 to induce DC differentiation. The cells were incubated with theophylline, KF17837 (a selective A2a receptor antagonist) and enprofylline (A2b receptor antagonist) and co-incubated with selective adenosine A1 and A2a receptor agonists, a phosphodiesterase inhibitor (rolipram) and adenosine deaminase (ADA) to determine their effects on DC differentiation. In addition, depletion of adenosine receptors by small interfering RNA (siRNA) was also examined.

RESULTS

Monocytes differentiated into myeloid DCs in the culture system. The number of DCs was remarkably reduced by 60-70% when theophylline was administered at a therapeutic concentration. This effect was concentration-dependently exacerbated, was partly mediated by cellular apoptosis and was effectively reversed by the addition of the A1 agonists [2-chloro-N(6)-cyclopentyladenosin, N(6)-cyclohexyladenosine, and N-ethylcarboxamidoadenosine (NECA)] or the A2a agonist (CGS-21680, NECA). The depletion of the adenosine A1 receptor by siRNA and addition of ADA remarkably reduced DC differentiation. Meanwhile, both enprofylline and rolipram had little effect.

CONCLUSION

Our findings suggest that the adenosine A1 (and possibly coordinated with A2a) receptors contribute to DC differentiation and survival. These findings provide further evidence that theophylline has an anti-inflammatory action in bronchial asthma.

The effect of ascorbate on minor recurrent aphthous stomatitis

AIM

Minor recurrent aphthous stomatitis (MRAS) is a common, painful and inflammatory ailment of the oral cavity with juvenile onset and unknown aetiology. The purpose of this study was to evaluate the potential of ascorbate (vitamin C) to reduce the frequency of MRAS and severity of pain.

PATIENTS AND METHODS

Sixteen MRAS patients (9 boys and 7 girls: mean age, 12.0 +/- 2.4 years old) were assigned to take an oral dosage of 2000 mg/m(2)/day ascorbate.

SUBJECTS

Their baseline frequency of outbreaks and the level of pains were compared during the treatment; in addition, a crossover clinical trial was performed. Polymorphonuclear leucocytes play a role in the pathogenesis, and then superoxide anion production was evaluated in prior to ascorbate treatment.

RESULTS

The data indicated a statistically significant 50% reduction in oral ulcer outbreaks and a decline of pain level. Neutrophils were primed for superoxide anion production in the patients with MRAS.

CONCLUSION

Ascorbate may modulate the generation of reactive oxygen species and augment neutrophil apoptosis, which could prevent neutrophil-mediated inflammation. Ascorbate seems to be effective, but the findings of our study were preliminary and it should be re-evaluated with a larger randomized controlled clinical trials.