Seroprevalence of Hepatitis A, B, and C in Syrian Refugee Children Newly Diagnosed With Cancer.

Adult survivors of childhood cancer have an increased incidence of hepatitis due to immunosuppression and frequent blood transfusions. The immunization of children with cancer is critical for hepatitis prevention, however, access to vaccination may be restricted during times of war, such as the Syrian armed conflict. The goal of this study was to assess the pretreatment serological status of hepatitis A, B, and C in 48 Syrian refugee children with cancer diagnosed in our center between 2014 and 2021. The control group consisted of 48 Turkish children with cancer who were age, sex, and disease-matched. Fifty-eight boys and 38 girls, with a median age of 4.8 years, were included. There were 42 patients with hematological malignancies, 20 with central nervous tumors, and 34 with other solid tumors. The frequency of hepatitis A seroprevalence was not statistically different between Syrian and Turkish patients, whereas hepatitis B seroprotectivity was found to be significantly lower in Syrian children with cancer than in Turkish children. Two Syrian patients were hepatitis C virus-positive. Thirty-seven percent and 45% of all patients were seronegative for hepatitis B and hepatitis A, respectively. Our findings support the need for hepatitis screening and, if necessary, vaccination of this vulnerable population before chemotherapy.

Functional brain plasticity following childhood maltreatment: A longitudinal fMRI investigation of autobiographical memory processing.

Altered autobiographical memory (ABM) processing characterizes some individuals with experiences of childhood maltreatment. This fMRI study of ABM processing evaluated potential developmental plasticity in neural functioning following maltreatment. Adolescents with (N = 19; MT group) and without (N = 18; Non-MT group) documented childhood maltreatment recalled specific ABMs in response to emotionally valenced cue words during fMRI at baseline (age 12.71 ± 1.48) and follow-up (14.88 ± 1.53 years). Psychological assessments were collected at both timepoints. Longitudinal analyses were carried out with BOLD signal changes during ABM recall and psychopathology to investigate change over time. In both groups there was relative stability of the ABM brain network, with some developmental maturational changes observed in cortical midline structures (ventromedial PFC (vmPFC), posterior cingulate cortex (pCC), and retrosplenial cortex (rSC). Significantly increased activation of the right rSC was observed only in the MT group, which was associated with improved psychological functioning. Baseline group differences in relation to hippocampal functioning, were not detected at follow-up. This study provides preliminary empirical evidence of functional developmental plasticity in children with documented maltreatment experience using fMRI. This suggests that altered patterns of brain function, associated with maltreatment experience, are not fixed and may reflect the potential to track a neural basis of resilience.

IFN-γ stimulation of dental follicle mesenchymal stem cells modulates immune response of CD4+ T lymphocytes in Der p1+ asthmatic patients in vitro

Background: House dust mite (Dermataphagoides pteronyssinus) is a widespread risk factor in the development of asthma. CD4+ T lymphocytes have an important role in the pathogenesis of allergic asthma by polarizing to Th2 cells. Objective: We aimed to evaluate the immunoregulatory effects of dental follicle mesenchymal stem cells with and without IFN-γ stimulation on peripheral blood mononuclear cells of house dust mite sensitive asthmatic patients, and compared those with Dexamethasone as a systemic steroid. Material and methods: PBMC of asthmatic patients and healthy individuals separately cultured with or without DF-MSCs in the presence and absence of IFN-γ or Der p1 or Dexamethasone for 72h. CD4+ T proliferation, cell viability, CD4+CD25+FoxP3+ Treg cell frequency and cytokine profiles of PBMC were evaluated via flow cytometry. Results: DF-MSCs suppressed proliferation of CD4+ T lymphocytes (pCDmix < 0.01, pDerp1 < 0.01, pIFN < 0.005) by increasing the number of FoxP3 expressing CD4 + CD25 + T regulatory cells (pCDmix < 0.005, pDerp1 < 0.01, pIFN < 0.001) and suppressed lymphocyte apoptosis (pCDmix < 0.05, pDerp1< 0.05, pIFN < 0.05), while Dexamethasone increased the apoptosis and decreased Treg cell frequency in asthmatic patients. IFN-γ stimulation increased the suppressive effect of DF-MSCs and also enhanced the frequency of FoxP3 expressing CD4+CD25 + T regulatory cells. The cytokine levels were regulated by DF-MSCs by reducing IL-4 cytokine levels (pCDmix < 0.01, pDerp1 < 0.05, pIFN < 0.05) and upregulating IFN-γ levels (pCDmix < 0.01, pDerp1< 0.05, pIFN < 0.005) in asthmatic patients. Conclusion: IFN-γ stimulated DF-MSCs were found to have a high modulatory effect on CD4 + T cell responses, while Dexamethasone had an apoptotic effect on CD4+ T cells in asthmatic patients. DF-MSCs may be a new cell-based therapy option for allergic diseases including asthma

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IFN-γ stimulation of dental follicle mesenchymal stem cells modulates immune response of CD4+ T lymphocytes in Der p1+ asthmatic patients in vitro.

BACKGROUND: House dust mite (Dermataphagoides pteronyssinus) is a widespread risk factor in the development of asthma. CD4+ T lymphocytes have an important role in the pathogenesis of allergic asthma by polarizing to Th2 cells. OBJECTIVE: We aimed to evaluate the immunoregulatory effects of dental follicle mesenchymal stem cells with and without IFN-γ stimulation on peripheral blood mononuclear cells of house dust mite sensitive asthmatic patients, and compared those with Dexamethasone as a systemic steroid. MATERIAL AND METHODS: PBMC of asthmatic patients and healthy individuals separately cultured with or without DF-MSCs in the presence and absence of IFN-γ or Der p1 or Dexamethasone for 72h. CD4+ T proliferation, cell viability, CD4+CD25+FoxP3+ Treg cell frequency and cytokine profiles of PBMC were evaluated via flow cytometry. RESULTS: DF-MSCs suppressed proliferation of CD4+ T lymphocytes (pCDmix<0.01, pDerp1<0.01, pIFN<0.005) by increasing the number of FoxP3 expressing CD4+CD25+ T regulatory cells (pCDmix<0.005, pDerp1<0.01, pIFN<0.001) and suppressed lymphocyte apoptosis (pCDmix<0.05, pDerp1<0.05, pIFN<0.05), while Dexamethasone increased the apoptosis and decreased Treg cell frequency in asthmatic patients. IFN-γ stimulation increased the suppressive effect of DF-MSCs and also enhanced the frequency of FoxP3 expressing CD4+CD25+ T regulatory cells. The cytokine levels were regulated by DF-MSCs by reducing IL-4 cytokine levels (pCDmix<0.01, pDerp1<0.05, pIFN<0.05) and upregulating IFN-γ levels (pCDmix<0.01, pDerp1<0.05, pIFN<0.005) in asthmatic patients. CONCLUSION: IFN-γ stimulated DF-MSCs were found to have a high modulatory effect on CD4+ T cell responses, while Dexamethasone had an apoptotic effect on CD4+ T cells in asthmatic patients. DF-MSCs may be a new cell-based therapy option for allergic diseases including asthma.

Dental follicle mesenchymal stem cells down-regulate Th2-mediated immune response in asthmatic patients mononuclear cells.

BACKGROUND: Asthma is a chronic inflammatory disease in which inflammatory responses have the polarisation of CD4+ T cells to Th2 cells. Dental follicle mesenchymal stem cells (DFSCs) have strong anti-inflammatory properties comparable to other mesenchymal stem cells. OBJECTIVE: We investigated the immunomodulatory effects of DFSCs on CD4+ T helper cell responses of asthmatic patients and compared the results with those obtained with asthmatic subjects on immunotherapy and with healthy individuals. METHOD: Peripheral blood mononuclear cells (PBMC) were isolated from immunotherapy naïve asthmatics, asthmatics on subcutaneous Der p1 immunotherapy and from healthy individuals. PBMC were pre-conditioned with anti-CD3/anti-CD28 mAbs, Der p1 or IFN-γ in the presence and absence of DFSCs and analysed for T cell viability and proliferation, CD4+ CD25+ FOXP3+ regulatory T cell frequencies, cytokine expression, and GATA3, T bet and FoxP3 expressions. Neutralisation of TGF-ß and blockade of IDO and PGE2 pathways were performed to determine suppressive signalling pathways of DFSCs. RESULTS: Dental follicle mesenchymal stem cells suppressed proliferative responses of CD4+ T lymphocytes and increased the frequency of Treg cells. DFSCs decreased effector and effector memory CD4+ T cell phenotypes in favour of naïve T cell markers. DFSCs decreased IL-4 and GATA3 expression and increased IFN-γ, T-bet and IL-10 expression in asthmatics. Costimulatory molecules were suppressed in monocytes with DFSCs in the cocultures. DFSCs down-regulated inflammatory responses via IDO and TGF-ß pathways in asthmatic patients. CONCLUSION: Dental follicle mesenchymal stem cells suppressed allergen-induced Th2-cell polarisation in favour of Th1 responses and attenuated antigen-presenting cell co-stimulatory activities. These studies suggest that DFSC-based cell therapy may provide pro-tolerogenic immunomodulation relevant to allergic diseases such as asthma.

Vitamin D in childhood cancer: a promising anticancer agent?

Children diagnosed and treated for cancer are vulnerable to Vitamin D deficiency depending on many factors. The Vitamin D status in children with cancer has been mostly regarded as a contributory factor for skeletal pathologies so far. However, the calcitriol was found to promote cell differentiation, inhibit malignant proliferation, and exhibit antiinflammatory, proapoptotic and antiangiogenic properties. In addition to this, numerous epidemiological studies link Vitamin D and cancer and indicate to possible role of Vitamin D in cancer pathogenesis and progression. This article aims to provide an overview of the possible role of Vitamin D deficiency in childhood cancer in terms of prevention and treatment.

Accuracy of imaging-guided biopsy in diagnosis of malignancy versus infection.

AIMS: Imaging-guided biopsies obtain samples for pathologic testing in addition to therapeutic interventions in patients with cancer. Our aim was to determine the diagnostic accuracy of percutaneous biopsies of pediatric solid tumors and infectious complications of cancer treatment. MATERIALS AND METHODS: This study was performed by gathering pediatric oncology patients between 1998 and 2008. A total of 41 percutaneous biopsies were performed in order to establish a diagnosis for a suspected malignancy or an infectious complication of cancer treatment. RESULTS AND CONCLUSIONS: An accurate diagnosis was achieved in 21 of 26 (87.6%) percutaneous biopsies for suspected malignancy cases or recurrence. The remaining 15 percutaneous biopsies were done for the diagnosis of infectious complications of cancer treatment with an accurate diagnosis of 60%. Imaging-guided percutaneous biopsy technique is highly accurate and safe, particularly in diagnosis of a suspected tumor.

McCune-Albright syndrome mimicking malignancy: an endocrine disease from oncologist's perspective.

Fibrous dysplasia (FD) is categorized as either monostotic or polyostotic and may occur as a component of McCune-Albright syndrome (MAS). Imaging findings can mimic neoplastic diseases. We present a case of MAS initially suspected to have neoplastic disease. A 9-year-old girl was admitted to pediatric emergency with ataxia. Upon hospitalization, an extradural mass was seen on cranial magnetic resonance imaging (MRI) and the bone survey showed lytic lesions in the long bones. The patient was referred to the pediatric oncology department with a presumptive diagnosis of Langerhans cell histiocytosis or metastatic tumor. Further investigations demonstrated that the patient had MAS and coexisting postinfectious cerebellitis. The findings in this patient demonstrate that the radiographic findings and the clinical presentation of FD and MAS may be similar to those of malignant diseases.

Air pollution forecasting in Ankara, Turkey using air pollution index and its relation to assimilative capacity of the atmosphere.

Spatial and temporal variations in concentrations of CO, NO, NO(2), SO(2), and PM(10), measured between 1999 and 2000, at traffic-impacted and residential stations in Ankara were investigated. Air quality in residential areas was found to be influenced by traffic activities in the city. Pollutant ratios were proven to be reliable tracers to differentiate between different sources. Air pollution index (API) of the whole city was calculated to evaluate the level of air quality in Ankara. Multiple linear regression model was developed for forecasting API in Ankara. The correlation coefficients were found to be 0.79 and 0.63 for different time periods. The assimilative capacity of Ankara atmosphere was calculated in terms of ventilation coefficient (VC). The relation between API and VC was investigated and found that the air quality in Ankara was determined by meteorology rather than emissions.

Rasmussen encephalitis in childhood.

Six patients admitted to the Department of Pediatric Neurology at Hacettepe University Children's Hospital between 1992 and 1997 with a clinical diagnosis of Rasmussen encephalitis received surgical treatment for their intractable epilepsy. MRI, SPECT and WADA tests were performed in patients with an epileptic focus demonstrated on routine or long-term video EEG monitoring. Viral studies using the PCR methodology were performed in cases with histopathological evidence of Rasmussen encephalitis. The ages of these patients ranged between 7 and 16 years, and the mean age at onset of seizures was 7.1+/-2.2 years. In four patients seizures presented as epilepsia partialis continua and were refractory to anticonvulsive drug therapy. In three cases intravenous immunoglobulin therapy yielded temporary and partial improvement in seizure control. The mean presurgical follow-up duration was 2.04+1.74 years, and early surgical intervention for epilepsy was performed in one case. The surgical approach selected for the treatment of epilepsy was resective surgery with electrocorticography. The mean postoperative follow-up duration was 32.3+17.2 months. Seizures were fully controlled in one patient, in whom surgery was performed 3 months after the seizures first started. Early surgical intervention may provide histopathological evidence for diagnosis as well as effective seizure control.

Long-term follow-up of indirect hyperbilirubinemia in full-term Turkish infants.

OBJECTIVE: This retrospective follow-up study was performed to evaluate the suitability of the recently reported exchange transfusion limits (serum indirect bilirubin level of 428-496 mumol/1, 25-29 mg/dl) for Turkey. MATERIAL AND METHODS: The study groups totalled 102 children, 8-13 years of age, who had been born at term with birthweights greater than 3000 g and had been treated for indirect hyperbilirubinemia during their newborn period; the control group consisted of 27 children of the same age-group without indirect hyperbilirubinemia. Children were grouped according to their maximum serum and bilirubin levels and direct Coomb's test results. Physical and neurological examinations, visual and brainstem auditory evoked potentials and the Wechsler Intelligence Scale for children--Revised for Turkish Children were performed. RESULTS: There was no difference between the groups with regard to mean visual and brainstem auditory evoked potential latencies. Children whose direct Coomb's tests were positive had significantly lower IQ scores and more prominent neurological abnormalities (p < 0.05). IQ scores and prominent neurological abnormalities did not differ among the other groups. Nine children had prominent neurological abnormalities associated with abnormal brainstem auditory evoked potentials. An important risk factor was the duration that the infant's serum indirect bilirubin level remained greater than 342 mumol/l (20 mg/dl). CONCLUSION: The current limit of 342 mumol/l should continue to be used for infants whose direct Coomb's tests are positive in our country. Until better criteria for exchange transfusion other than the indirect bilirubin level are established, the current limits should also still be followed for infants whose direct Coomb's tests are negative in Turkey, where regular neonatal follow-up examinations are not satisfactory.