Electronic cigarette liquid substances propylene glycol and vegetable glycerin induce an inflammatory response in gingival epithelial cells.

Information on the effects of propylene glycol (PG) and vegetable glycerin (VG) and on cytotoxicity and subsequent activation of the biological mediators is limited in periodontal diseases. This study analyzes the effect of unflavored PG/VG alone or in combination with nicotine on gingival epithelial cells. The cells were exposed to different PG/VG (± nicotine) concentrations for 24 h and cytotoxicity was evaluated by calorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromid assay. The expressions of interleukin (IL)-6, IL-8, and matrix metalloproteinases (MMPs)-9 were measured using an enzyme-linked immunosorbent assay and a western blotting. Stimulation with PG/VG mixtures reduced cell viability compared to nonexposed controls (p < 0.05). Adding PG/VG increased the levels of IL-6, IL-8, and MMP-9, and the amount of PG had more biological impact compared to the VG amount. The nicotine augmented this effect compared to its nicotine-free counterparts. In western blotting result, MMP-9 was clearly activated in almost all samples. These findings suggest that the main constituents PG/VG are cytotoxic and able to induce biological response in gingival cells in vitro. Despite being advertised as less harmful than conventional cigarettes, electronic cigarette liquid pose certain risks on periodontal cells. Awareness about the effects of electronic cigarettes on periodontal diseases must be increased.

The function of TLR4 in interferon gamma or interleukin-13 exposed and lipopolysaccharide stimulated gingival epithelial cell cultures.

Gingival epithelial cells are part of the first line of host defense against infection. Toll-like receptors (TLRs) serve important immune and nonimmune functions. We investigated how interferon gamma (INF-γ) and interleukin 13 (IL-13) are involved in the TLR4 ligand-induced regulation of interleukin-8 (IL-8) effects on gingival epithelial cells. We used immunohistochemistry to localize TLR4 in ten healthy and ten periodontitis tissue specimens. Gingival epithelial cells then were primed with Th1 cytokine (INF-γ) or Th2 cytokine (IL-13) before stimulation with Escherichia coli-derived lipopolysaccharide (LPS) and enzyme-linked immunosorbent assay (ELISA) was performed to detect the level of IL-8 secretion in cell culture supernatants. Although both healthy and periodontitis gingival tissue samples expressed TLR4, the periodontitis samples showed more intense expression on gingival epithelial cells. Gingival epithelial cell cultures were primed with either INF-γ or IL-13 before stimulation with TLR4 ligand. Supernatants from co-stimulated epithelial cells exhibited IL-8 production in opposite directions, i.e., as one stimulates the release, the other reduces the release. INF-γ significantly increased TLR4 function, whereas IL-13 significantly decreased TLR4 function, i.e., production of IL-8. Pathogen associated molecular pattern-LPS, shared by many different periodonto-pathogenic bacteria, activates the gingival epithelial cells in a TLR-dependent manner. Diminished or increased TLR function in gingival epithelial cells under the influence of different Th cell types may protect or be harmful due to the altered TLR signaling.

Dynamics in children and adolescents who experience varicella zoster virus infections after haematopoietic stem cell transplantation: a case-control study.

We evaluated the incidence of varicella-zoster virus (VZV) infections, including herpes zoster (HZ), and investigated the associated risk factors for HZ and compared lymphocyte subsets of these patients at 1, 3 and 6 months following haematopoietic stem cell transplantation (HSCT) in a case-control study in children and adolescents. The incidence of HZ infection at the first year after HSCT was 17/125 (13·6%). The cumulative incidence of HZ infection was 22/125 (17·6%). Sixteen (73%) cases with HZ and 11 (32%) cases in the control group had a diagnosis of malignant disorder. No significant difference was noted between the HZ group and the control group in absolute lymphocyte number and subsets (except WBC) at the pre-transplant evaluation. Pre-transplant WBC count was statistically lower in the HZ group (P<0·05). The CD4/CD8 ratios were lower in the HZ group during the first 6 months after HSCT, and the decrease was statistically significant at 6 months compared to the control group. In conclusion, patients undergoing HSCT for a malignant disorder had a significantly higher risk of VZV infection than those with non-malignant disorders and pretransplant donor characteristics were not helpful in predicting risk of post-transplant VZV infection.

Naturally acquired hepatitis A antibodies after haematopoetic stem cell transplantation.

Haematopoietic stem cell transplant (HSCT) recipients lose immune memory of exposure to infectious agents and vaccines accumulated throughout their lifetime and therefore need to be revaccinated. We aimed to evaluate the influence of different factors on hepatitis A virus (HAV) immunity in both child and adult HSCT recipients living in an intermediate endemic region, Turkey. Eighty patients (age range 2·5-57 years) who had HAV serology prior to HSCT were evaluated. The prevalence of HAV seropositivity was 85% (n=68) before HSCT. There was no history of HAV vaccination before HSCT in children and HAV vaccine was not available in Turkey 10 years ago, so it was assumed that all seropositive patients reflected natural immunity. After the exclusion of six patients with autologous HSCT, the remaining 62 seropositive and allogeneic patients were included in this retrospective study. The duration of HAV seropositivity was estimated using the Kaplan-Meier method, log-rank analysis and Cox regression models. Estimated mean time to loss of HAV seropositivity was 48·6 months after transplantation. Patients who were older (⩾18 years) at transplantation and who had older (⩾18 years) donors became seronegative later (P<0·05). Cox backward-stepwise regression confirmed that older age of recipient at transplantation was the only significant parameter for HAV seropositivity (P<0·05). HAV-inactivated vaccine might be recommended later to older HSCT recipients in intermediate endemic regions.

Adipocyte differentiation defect in mesenchymal stromal cells of patients with malignant infantile osteopetrosis.

BACKGROUND: Malignant infantile osteopetrosis (MIOP) is a disorder of osteoclasts characterized by defective bone resorption and death in infancy. The multipotent mesenchymal stromal cells (MSC) and their progeny (osteoblasts) are major components of the bone marrow (BM) microenvironment and are found in close contact with cells of hematopoietic origin, including osteoclasts. We hypothesized that MSC defects may be associated with osteoclast dysfunction and osteopetrosis phenotype. METHODS: BM MSC, obtained from six patients with MIOP, were expanded in vitro and characterized by morphology, plastic-adherence, immunophenotype and multilineage differentiation potential. RESULTS: Physical and immunophenotypic characteristics of patient MSC were similar to healthy age-matched controls. However, an isolated in vitro differentiation defect toward adipogenic lineage was demonstrated in patient MSC and confirmed by low or absent expression of adipogenic transcripts (peroxisome proliferator-activated receptor-gamma, adipophilin, stearoyl-CoA desaturase, leptin and adiponectin) upon induction of adipogenesis. Following BM transplantation, minimal improvement in adipogenic potency of MSC was demonstrated by Oil Red O staining. DISCUSSION: MIOP is associated in vitro with a failure of MSC to differentiate into an adipogenic lineage, suggesting a BM microenvironment defect. The defect may contribute to osteoclast dysfunction, or may be attributed to the effect of the osteopetrotic marrow environment. Further investigations should determine the pathophysiologic importance of this novel defect, and could perhaps contribute to consideration of MSC therapy in MIOP.

Atypical skin graft-vs.-host disease following bone marrow transplantation in an infant.

Herein, we describe an unusual presentation of acute graft versus host disease (GVHD) mimicking contact dermatitis in an infant who underwent 5/6 HLA-matched bone marrow transplantation (BMT) from his mother for malignant infantile osteopetrosis. The initial rash on day +32 simulated diaper rash, which progressed to a belt-shaped rash and then developed hyperkeratotic nodules on the hands. The acute GVHD was atypical and the course was progressive and fatal, with liver and gut involvement. This presentation of atypical initial skin involvement of acute GVHD may be useful for practicing clinicians in the BMT field who need to be aware of the early unusual signs of acute GVHD so that they can initiate prompt treatment.

Cigarette smoking and apoptosis.

BACKGROUND: Epithelial cell hyperplasia and significant increase in thickness of the overlying orthokeratin layer are characteristic findings noted in the oral cavity of subjects who smoke. Increased proliferation of epithelial cells or defective apoptosis may play a role in the development of epithelial hyperplasia. Thus we analyzed soluble Fas and nuclear matrix protein (NMP) levels in the saliva of smokers (N = 13) and non-smokers (N = 14) to assess apoptosis. METHODS: Ten ml of unstimulated saliva samples was obtained from 14 non-smoker and 13 smoker subjects with the spitting method. These samples were analyzed by using an immunoassay kit to detect soluble human APO-1/Fas and cell death detection enzyme-linked immunosorbent assay (ELISA) kit based on nuclear matrix protein 41/7 qualification. RESULTS: The mean soluble Fas levels were 153.8 +/- 290 pg/ml and 315.4 +/- 490 pg/ml and NMP levels were 21.81 +/- 10.70 U/ml and 30.31 +/- 19.86 U/ml, respectively, in smokers and nonsmokers. The difference between NMP levels of smoker and non-smoker groups was statistically significant (P = 0.05). CONCLUSION: The results of the present study suggest that smoking may induce anti-apoptotic mechanism in the oral cavity.

Expression of Fas and Fas-ligand and analysis of argyrophilic nucleolar organizer regions in squamous cell carcinoma: relationships with tumor stage and grade, and apoptosis.

The aim of this study was to investigate whether levels of Fas and Fas-ligand (Fas-L) expression in oral and oropharyngeal squamous cell carcinomas (SCCs) are associated with tumor stage and grade, and to assess whether parameters related to argyrophilic nucleolar organizer regions (AgNORs) correlate with apoptosis in SCC cells and adjacent normal epithelium. Fifty-two specimens taken from the tumoral and neighboring normal tissues of 26 patients with oral and oropharyngeal SCC were analyzed for Fas/Fas-L expression, and 24 specimens from 12 patients for AgNOR parameters. Seventeen (65%) of the tumors were Fas and/or Fas-L-positive (by immunohistochemistry). A significant positive correlation was found between Fas/Fas-L expression and clinical tumor stage (P<0.01). Mean AgNOR number per nucleus, AgNOR size and the percentage area of each nucleus occupied by AgNORs (percent of nuclear area) were significantly increased in the SCC cells (4.49+/-1.28, 4.48+/-1.42, 5.56+/-1.22, respectively) when compared with the control neighboring squamous epithelial cells (2.58+/-0.61, 1.64+/-0.59 and 4.35+/-0.62%, respectively) (P<0.01). A significant positive correlation was found between the AgNOR parameters and Fas/Fas-L expression as apoptotic markers in the tumoral cells of SCC (P<0.05). There was also a significant positive correlation between the AgNOR parameters and the grading of tumors (P<0.05). In conclusion, AgNOR count was a strong proliferation marker in patients with SCC, and Fas and Fas-L staining was useful in tumor grading.

Life-threatening neurological complications after bone marrow transplantation in children.

Neurological complications may occur in BMT recipients (11-59%), frequently contributing to morbidity or mortality. They are the main causes of death in 10-15%. Life-threatening neurological complications were seen in 11 out of 113 (9.7%) children who underwent BMT from HLA-matched family (n=7) or mismatched donors (n=4) at our institution. Diagnoses of patients with neurological complications were acute myeloblastic leukemia (AML) (five), thalassemia major (two), Fanconi anemia (two), Omenn syndrome (one) and leukodystrophy (one), and the neurological events were seen between days +13 and +85 after transplantation. Minor symptoms including reversible, nonrepetitive seizures were excluded. Cyclosporine A toxicity was diagnosed in six children. The rest of the complications were brain abscess/meningoencephalitis (two), severe hypomagnesemia (one), busulfan toxicity (one), sustained hypertension (three), and intracranial hemorrhage (three). Six patients with neurological complications suffered from >grade II graft-versus-host disease (GvHD), and all were high risk for transplant-related complications. In this study, risk status of the underlying disease, mismatched transplantation, a diagnosis of AML (advanced stage), older age and >grade II GvHD were important adverse factors for the development of severe life-threatening neurological complications.

The role of apoptosis in childhood Henoch-Schonlein purpura.

The pathogenesis of vasculitis is complex and is yet to be fully elucidated, although it is known that inflammatory cells play a major role. Dysregulation of apoptosis and defective clearance of inflammatory cells could lead to the persistence of inflammation and excessive tissue injury. In this study we aimed to investigate Fas (CD95) and apoptosis on peripheral blood (PB) neutrophil and lymphocytes in Henoch-Schonlein purpura, both in the acute phase and after resolution to determine the role of apoptosis in this self-limited vasculitis. Leukocytoclastic vasculitis presenting with Henoch-Schonlein purpura (HSP) was diagnosed according to ACR 1990 criteria and confirmed by skin biopsy. Thirty-seven patients (22 boys, 15 girls) aged 2.5-17 years (9 +/- 3.3) were enrolled in the study. Expression of CD95 and apoptosis were investigated by the annexin/PI method on peripheral blood neutrophils and lymphocytes in both the acute and the resolution phases of the disease. The mean neutrophil and lymphocyte CD95 expression was 65.4 +/- 37.6% and 33.3 +/- 7.3%, respectively, in the acute stage and 62.8 +/- 44.2% and 41 +/- 20%, respectively, in the resolution ( P > 0.05). The percentage of apoptotic peripheral blood neutrophils and lymphocytes as determined by annexin positivity was 13.3 +/- 11.31% and 8.6 +/- 9.5%, respectively, during the acute phase and 4.6 +/- 3.4% and 3.1 +/- 3.1%, respectively, in the resolution (P = 0.002, P = 0.008). These results suggest that increased apoptotic process in the immune effector cells in the acute phase of the disease may play an important role in the early control of inflammatory response and repair in leukocytoclastic vasculitis, thereby contributing to the self-limited nature of the disease.

Long-term outcome of haematopoietic stem cell transplantation in autosomal recessive osteopetrosis: an EBMT report.

A retrospective analysis was made of 122 children who had received an allogeneic haematopoietic stem cell transplantation (HSCT) for autosomal recessive osteopetrosis between 1980 and 2001. The actuarial probabilities of 5 years disease free survival were 73% for recipients of a genotype HLA-identical HSCT (n=40), 43% for recipients of a phenotype HLA-identical or one HLA-antigen mismatch graft from a related donor (n=21), 40% for recipients of a graft from a matched unrelated donor (n=20) and 24% for patients who received a graft from an HLA-haplotype-mismatch related donor (n=41). In the latter group, a trend towards improvement was achieved at the end of the study period (17% before 1994, 45% after 1994, P=0.11). Causes of death after HSCT were graft failure and early transplant-related complications. Severe visual impairment was present in 42% of the children before HSCT. Conservation of vision was better in children transplanted before the age of 3 months. Final height was related to height at the time of HSCT and better preserved in children transplanted early. Most children attended regular school or education for the visually handicapped. At present, HSCT is the only curative treatment for autosomal recessive osteopetrosis and should be offered as early as possible.

Serum zinc and alkaline phosphatase values in pediatric bone marrow transplantation patients.

Zinc (Zn) plays an important role in the maintenance of immune functions, including cellular/humoral immunity, and in the prevention of oxidative injury. Therefore, the maintenance of a normal Zn status may be important in bone marrow transplantation (BMT) patients. Serum Zn levels were determined in 35 children during the BMT period. In addition, as Zn-related factors, serum Cu levels and alkaline phosphatase (AP) activity were also measured. There was a significant decrease in Zn and AP values during the immediate post-transplant period (lowest at day +7) when compared to pre-BMT levels (p <.01). The patients who developed hypozincemia were more likely to be transplanted for a diagnosis of malignant disorder and were younger, and adverse events appeared to occur more frequently. This preliminary study suggests that maintaining a normal Zn status may be important in BMT patients and that Zn deficiency may be a risk factor for adverse events.

The effects of high dose methylprednisolone on apoptosis in children with acute lymphoblastic leukemia.

Rapid leukemic cell kill at initial diagnosis of patients with acute lymphoblastic leukemia (ALL) has been shown to be associated with a favorable outcome. The aim of the present study was to investigate the effect of high dose methylprednisolone (HDMP) on in vivo blast cell apoptosis in children with ALL. Annexin V-binding and Fas (CD95), Fas ligand (FasL; CD95L), and Bcl-2 expression in PB blasts were determined in newly diagnosed children with ALL before and 4, 24, 96 h after initiation of HDMP treatment (n=20) or conventional dose steroids (CDS) (n=10) as the control group. A decrease in absolute blast count (from 40.8 x 09 to 21.4 x 109/l) associated with an increase in apoptosis (14.2 to 26.9%) (P < 0.05) was detected 4 h after initiation of HDMP. A significant increase in Fas and FasL expression was detected 96 h after HDMP. There was no significant change in apoptosis, Fas and FasL expression from baseline in the control group treated with CDS. The changes in Bcl-2 expression after treatment was not significant in both groups. The results of this preliminary study have shown that HDMP treatment was effective in inducing immediate (within 4 h) blast cell apoptosis. The contribution of Fas/FasL interaction in the rapid component of cell kill remains to be determined, as the increase in the expression of these molecules was evident later.

Evaluation of coagulation in pediatric bone marrow transplantation patients.

A hypercoagulable state is frequently described in adult patients undergoing bone marrow transplantation (BMT). In this study, the coagulation profile of 29 children was prospectively investigated in the pre- and post-transplant period. A significant rise in the activated partial thromboplastin time (aPTT) values was detected on days 7 and 14 after transplantation. Moreover, an increase in the d-dimer level was also notable, regardless of the clinical condition of the patients. The other coagulation parameters investigated (i.e. protein S, protein C, anti-thrombin III, factor VIII, von Willebrand factor, and prothrombin time) remained essentially unchanged. However, hyper-fibrinogenemia was observed in all patients with chronic myeloid leukemia (CML) (n=5) before and after transplantation. In summary, in the present study pediatric bone marrow transplantation patients did not show a hyper-coagulable state after marrow infusion. However, a significant rise in PTT and d-dimer values were noted.

Pneumatosis intestinalis in an infant undergoing bone marrow transplantation for Wiskott-Aldrich syndrome.

A 7-month-old patient with Wiskott-Aldrich syndrome (WAS) developed pneumatosis intestinalis (PI) in the immediate post-transplant period after receiving paternal human leucocyte antigen (HLA) phenotypically matched bone marrow (BM). PI has been described in patients with congenital or acquired immunodeficiency states and after bone marrow transplantation (BMT). To our knowledge, the condition has not been described in WAS. The underlying bowel mucosa damage as a result of the history of massive rectal bleeding, the effects of the conditioning regimen, immunosuppression, neutropenia, and infection, may all have contributed to the development of PI. Although the condition resolved by conservative management alone, the patient developed Klebsiella pneumonia sepsis, interstitial pneumonitis, failed to engraft, and died on day +66 following a second infusion of stem cells mobilized from his father's peripheral blood.

The analysis of eosinophil and lymphocyte phenotype following single dose of high-dose methylprednisolone in two siblings with marked hypereosinophilia.

The effect of single high-dose methylprednisolone (HDMP) on eosinophil and lymphocyte phenotype in two siblings with marked hypereosinophilia was investigated. Since conventional dose steroids failed to produce a haematological and clinical response in case one, both children were given HDMP (20 mg/kg/day). Eosinophils and lymphocytes showed an activated state before treatment, characterized by marked expression of CD11b, CD18, CD45RO on eosinophils and increased HLA-DR, CD95, CD18, CD38 on lymphocytes. Twenty-four hours after administration of HDMP a dramatic reduction in peripheral blood eosinophil count was observed in both patients associated with phenotypic changes characterized by decreased expression of CD11b, CD18, CD13 and increased CD95 expression in one. Furthermore, HDMP treatment induced a drop in the expression of CD95 and CD18 on lymphocytes. These changes may suggest a suppressive role for HDMP on eosinophil and lymphocyte activation which may have contributed to the haematological and clinical response.

Increased neutrophil apoptosis during attacks of familial Mediterranean fever.

AIM: Apoptosis is a programmed form of cell death. Recently much attention has been devoted to the role of apoptosis in rheumatological diseases. We have aimed to analyze apoptosis in the inflammatory pathway of familial Mediterranean fever (FMF). METHODS: 26 FMF patients and 12 age and sex matched controls were the subject of the study. Twelve of the patients were analyzed during an FMF attack whereas samples were obtained at least a week after an attack in 14. Four of the patients had renal amyloidosis. Whole blood was treated with ammonium chloride for RBC lysis. Subsequently the cells were stained with propidium iodide and annexin. Neutrophils and lymphocytes were gated separately for analysis by flow cytometry. We have also analyzed cellular Fas and Fas-ligand expression in these cells. RESULTS: The mean age of the patients was 12.00 +/- 3.17, and was not different than the control subjects. Erythrocyte sedimentation rate and CRP levels were significantly elevated in the attack group as compared to the attack-free group. The mean levels of neutrophil apoptosis in the FMF patients with an attack, attack-free and controls were 12.94 +/- 11.78, 6.60 +/- 7.83 and 3.98 +/- 4.27, respectively. Lymphocyte apoptosis in the same groups were 7.84 +/- 8.63, 2.75 +/- 2.33, and 1.22 +/- 0.93, respectively. Neutrophil and monocyte apoptosis was significantly increased during the attack as compared to the controls (p < 0.05). However lymphocyte apoptosis was not different between the aforementioned groups. On the other hand, lymphocyte apoptosis was significantly increased in the SLE patients (p < 0.05), whereas neutrophil apoptosis was not. Fas staining of neutrophils were not different between the groups (p > 0.05). On the other hand the difference between the groups for FasL was significant (p < 0.05). CONCLUSION: Neutrophil and monocyte but not lymphocyte apoptosis was significantly increased during FMF attacks reminding us that FMF is an autoinflammation of certain peripheral cells. The increased apoptosis in these patients maybe regarded as a response to clear the unwanted inflammatory cells. On the other hand the increased apoptosis maybe the explanation of the self-limited nature of the FMF attacks. Future studies will enlighten us on the significance of this increased apoptosis in the process of inflammation.

Allogeneic bone marrow transplantation for children with myelodysplastic syndrome.

Six children with myelodysplastic syndrome underwent allogeneic bone marrow transplantation (BMT) from their HLA-identical siblings. Ages ranged from six to 16 years. French-American British (FAB) diagnosis was refractory anemia with excess blasts (RAEB) in three, RAEB in transformation (RAEB-t) in one and chronic myelomonocytic leukemia (CMML) in two cases. Two patients had progressed to leukemia before BMT. All patients received busulfan and cyclophosphamide as a conditioning regimen. Antithymocyte globulin (ATG) was administered to two of them due to the multiple transfusion history. Graft versus host disease (GvHD) prophylaxis consisted of cyclosporine-methotrexate. Engraftment was documented in all patients except one who underwent a second infusion of bone marrow cells. She died in the early post-transplant period with pancytopenia and veno-occlusive disease of the liver. Two patients died from disease recurrence. Three patients are alive > 12 months post-transplant, two are in remission and one just relapsed at +16 months and is now being prepared for a second bone marrow transplant. The only significant factor for favorable outcome was short duration between diagnosis to transplant in the two patients in remission.