Role of Vitamin D and Vitamin D Polymorphisms in COVID-19 Risk and Severity in Children: A Systematic Review.

The role of vitamin D in the susceptibility to coronavirus disease 2019 (COVID-19) disease has been investigated since the beginning of the pandemic, but there is still scarce data on children. We investigated the impact of vitamin D status and the related genetic variants on COVID-19 vulnerability and severity of the disease in children. A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, to identify reports on vitamin D status and genetic polymorphisms, their association with the susceptibility of children to COVID-19 and multisystem inflammatory syndrome in children (MIS-C), and the effect of supplementation on the clinical course.

Vaccination coverage of patients with type 2 diabetes mellitus: Challenging issues from an outpatient secondary care setting in Greece.

Background: Increased morbidity/mortality due to vaccine preventable diseases (VPD) is encountered in type 2 diabetes (T2D) people. Aim of this study was to assess their vaccination coverage and describe trends possibly affecting compliance.

Methods: Information on vaccination coverage was retrieved from either documents or interview provided by patients, and/or their vaccination record card at a specialized outpatient diabetes center.

Vaccine coverage in children, adolescents and adults with type 1 diabetes and their close contacts in Crete.

Background: Individuals with type 1 diabetes (T1D) are at increased risk of infections from vaccine-preventable diseases. This study focuses on compliance of T1D patients to the recommended vaccination schedule, vaccination of their close contacts for influenza and on factors potentially contributing to vaccination program deviations.

Methods: The study population comprised children, adolescents and adults with T1D under follow-up at the Department of Pediatrics University Hospital and the Diabetic Center General Hospital, Heraklion, Crete-Greece.

Cavitary tuberculosis re-emerging in immigrant children.

Unlabelled: Cavitary pulmonary tuberculosis in children is uncommon in areas with a low tuberculosis burden. We present two cases in an 11-year old immunocompetent girl and an 8-year old immunocompromised boy. Both children were immigrants.

Biological Features of Bone Marrow Mesenchymal Stromal Cells in Childhood Acute Lymphoblastic Leukemia.

Objective: Mesenchymal stromal cells (MSCs) have a supportive role in hematopoiesis and as components of the bone marrow (BM) microenvironment may present alterations during acute lymphoblastic leukemia (ALL) and be affected by chemotherapeutic agents. We examined the biological and functional characteristics of MSCs in ALL diagnosis and treatment and their effect on MSC qualitative properties.

Materials And Methods: Immunophenotypic characterization, evaluation of clonogenicity, and proliferative capacity were measured.

Non-tuberculous mycobacterial cervical lymphadenitis in the immunocompetent child: diagnostic and treatment approach.

Non-tuberculous mycobacterial disease in the otherwise well child commonly presents as a localized, slow-progressing, cervicofacial lymphadenopathy. Despite recent advances, several aspects of the susceptibility to and the course of the disease remain to be better understood, and diagnosis and management of non-tuberculous mycobacterial lymphadenitis in children are often controversial. Differential diagnosis should include other infections, in particular tuberculosis, local cysts and malignancies.

Expression levels of ASNS in mesenchymal stromal cells in childhood acute lymphoblastic leukemia.

Increased levels of asparagine synthetase (ASNS), an enzyme producing intracellular asparagine, have been implicated in the development of asparaginase resistance. The aim of this study was to assess ASNS mRNA and protein expression in bone marrow cell populations of children with acute lymphoblastic leukemia (ALL). Bone marrow mononuclear cells at diagnosis, day 33 of treatment, and after completion of chemotherapy were isolated and studied.

Enhanced levels of the apoptotic BAX/BCL-2 ratio in children with acute lymphoblastic leukemia and high-risk features.

It has been suggested that leukemia is characterized by an impaired balance between the proliferation of blood cells and their capacity to undergo apoptosis. The aim of this study was to examine the expression of key molecules related to apoptosis (BCL-2, BAX, FAS, FAS-L) in children with acute lymphoblastic leukemia (ALL). Measurement of BCL-2 and BAX mRNA was performed by quantitative real-time PCR, and membrane expression of FAS and FAS-L was assessed by flow cytometry in bone marrow mononuclear cells, both at diagnosis and at remission following induction chemotherapy.

Idiopathic thrombocytopenic purpura in childhood: twenty years of experience in a single center.

Background: Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder with a variable clinical course.

Methods: A retrospective analysis was carried out of ITP patients presenting to a pediatric hematology-oncology department during a period of 20 years, with a focus on treatment and outcome.

Results: One hundred and twenty-four cases were recorded (mean patient age, 8.

Are mesenchymal stromal cells from children resistant to apoptosis?

Objectives: Mesenchymal stromal cells (MSC) represent a novel cellular candidate in the field of transplantation and tissue regeneration. Their clinical application requires their in vitro expansion. The aim of this study was to assess the effect of conditions that would favour apoptosis, and of long-term expansion, on the characteristics of MSC from children.

Study of oncogenic transformation in ex vivo expanded mesenchymal cells, from paediatric bone marrow.

Objectives: Mesenchymal stromal cells (MSCs) have attracted considerable interest in both the scientific and clinical fields. In order to obtain a sufficient cell number for application, their in vitro expansion is necessary, but during this process their characteristics may be altered and cells may acquire oncogenic properties. We have investigated properties of MSC that may be related to oncogenesis, a critical parameter that has to be evaluated prior to MSC clinical use.

Could cord blood be a source of mesenchymal stromal cells for clinical use?

Background: Cord blood (CB) has long been regarded as an easily accessible source of hematopoietic progenitors suitable for transplantation, but its efficiency as a source of mesenchymal stromal cells (MSC) remains controversial. The aim of this study was to assess CB as a potential source of MSC, to determine the optimal culture requirements for CB MSC expansion and to compare their functional and immunophenotypic characteristics with bone marrow (BM) MSC from children.

Methods: Mononuclear cells from 18 full-term CB samples and 23 BM samples from children were set in culture under MSC-inducing conditions.

Properties and potential of bone marrow mesenchymal stromal cells from children with hematologic diseases.

Background: Mesenchymal stromal cells (MSC) have become the focus of cellular therapeutics but little is known regarding bone marrow (BM) MSC derived from children. As MSC constitute part of BM stroma, we examined their properties in children with hematologic diseases.

Methods: BM MSC from children with non-malignant hematologic disorders and acute lymphoblastic leukemia (ALL) were isolated and expanded.

Quantitative assessment of WT1 expression in diagnosis of childhood acute leukemia.

The purpose of this study was to investigate WT1 expression levels in childhood acute leukemia. Bone marrow from 14 children with acute leukemia at diagnosis and from 7 children with solid tumors without bone marrow involvement (control group) was studied. Five of the 14 patients (35.

Quantitative assessment of PRAME expression in diagnosis of childhood acute leukemia.

PRAME is expressed at low levels in normal testes and highly in solid tumor cells and hematological malignancies. The purpose of this study was to investigate PRAME expression levels in children with acute leukemia with real-time PCR analysis. Seventeen children with newly diagnosed or relapsed acute leukemia (11 ALL, 4 AML, 1 acute myeloblastic leukemia secondary to MDS, 1 ALL at relapse) and a control group of seven children were studied.

Yersinia enterocolitica infection mimicking surgical conditions.

Yersinia enteritis may present with alarming gastrointestinal manifestations. The aim of this study was to review the cases of children admitted to a general hospital with a preliminary diagnosis of surgical nature and subsequently proven to be infected by Yersinia enterocolitica. All cases of children aged less than 14 years with stool cultures positive for Y.

The impact of mode of delivery and gestational age on cord blood hematopoietic stem/progenitor cells.

Human cord blood has been successfully used as an alternative source of hematopoietic stem cells suitable for transplantation. The aim of this study was to assess the impact of gestational age and the mode of delivery on cord blood hematopoietic stem/progenitor cell characteristics. The mode of delivery does not seem to affect either the replating capacity of hematopoietic progenitors colony-forming unit-granulocyte-macrophage or the cord blood content in CD34(+) cells.

Adhesion molecules, endogenous granulocyte colony-stimulating factor levels and replating capacity of progenitors in autoimmune neutropenia of childhood.

Aim: To investigate the role of granulocyte colony-stimulating factor (G-CSF) and adhesion molecules and the response of bone marrow to peripheral cytopenia in autoimmune neutropenia of childhood (AIN).

Methods: Thirty-five children with AIN, 25 with acute leukaemia in remission, 10 of whom developed chemotherapy-associated neutropenia, and 28 non-neutropenic age-matched children were studied. The methods included haemopoietic progenitor cells' colony growth, replating of colony-forming unit-granulocyte macrophage (CFU-GM) of the 7th day and ELISA for the detection of serum levels of cytokines and adhesion molecules.

A novel idea for an organized hospital/school program for children with malignancies: issues in implementation.

The aim of this pilot study was to provide children with cancer hospitalized at the Department of Pediatric Hematology-Oncology of the University Hospital of Heraklion, Crete, with an educational program based on the SIOP guidelines. This would help them to follow the school program during the days of absence due to treatment. The realization of the initial idea generated difficulties that had to be overcome to achieve the goals and caused several changes in the program.

Levels of soluble ICAM-1 in premature and full-term neonates with infection.

Background: Infection in the neonatal period is an extremely serious condition and diagnosis is difficult. C-reactive protein (CRP) is widely used as a marker of infection; however, its usefulness is limited in the early phase. The role of soluble intracellular adhesion molecule-1 (sICAM-1), an adhesion molecule, has been examined in recent studies as an early marker of neonatal infection with controversial results.

Pleuropulmonary blastoma: an aggressive intrathoracic neoplasm of childhood.

A case of a 4-year-old girl with pleuropulmonary blastoma is reported. Surgical resection of the tumor was performed and histologic examination revealed pleuropulmonary blastoma with rhabdomyosarcomatous differentiation. Postoperative chemotherapy was administered and 3 weeks after initiation of treatment protocol a second site of lesion in the retroperitoneum was revealed with extension to the mediastinum, which shared similar mesenchymal neoplastic characteristics to the previously diagnosed primary lesion.