Direct ionizing radiation and bystander effect in mouse mesenchymal stem cells.

This study aimed to evaluate the radiation-induced direct and bystander (BYS) responses of mesenchymal stem cells (MSCs) and to characterize these cells radiobiologically. MSCs were irradiated (IR) and parameters related to DNA damage and cellular signaling were verified in a dose range from 0.5 to 15 Gy; also a transwell insert co-culture system was used to study medium-mediated BYS effects.

The Role of Low-Dose Radiation in Association with TNF-α on Immunomodulatory Properties of Mesenchymal Stem Cells.

Ionizing radiation (IR) is an important medical tool. Despite the effects associated with high-dose radiation during or after treatment, as well as in accidental exposures, the direct or indirect effect of low-dose IR in cells remain poorly documented. IR can affect the tissue microenvironment, including mesenchymal stem cells (MSCs), which have high regenerative and immunomodulatory capacities.

Meta-analysis of long-term efficacy and safety of hypofractionated radiotherapy in the treatment of early breast cancer.

Purpose: To evaluate the efficacy and safety of hypofractionated radiotherapy in women with early stage breast cancer after breast conservative surgery.

Methods: We performed a search for randomized controlled trials (RCTs) that compare conventional fractioning and hypofractioned radiotherapy. The studied outcomes were local and loco-regional recurrence, disease-free survival, mortality, cardiac ischemia, rib fracture and pulmonary fibrosis up to 5 years and 5 years after treatment.

A novel method to evaluate salivary flow rates of head and neck cancer patients after radiotherapy: a pilot study.

Introduction: The procedure used to evaluate salivary flow rate is called sialometry. It can be performed through several techniques, but none appears to be really efficient for post-radiotherapy patients.

Objective: To adequate sialometry tests for head and neck cancer patients submitted to radiotherapy.

Impact of low-level laser therapy on hyposalivation, salivary pH, and quality of life in head and neck cancer patients post-radiotherapy.

Late effects of radiotherapy for head and neck cancer treatment have been increasingly investigated due to its impact on patients' quality of life. The purpose of this study was to evaluate the effect of low-level laser therapy on hyposalivation, low salivary pH, and quality of life in head and neck cancer patients post-radiotherapy. Twenty-nine patients with radiation-induced xerostomia received laser sessions twice a week, during 3 months (24 sessions).

Low-Level Laser for Mitigation of Low Salivary Flow Rate in Head and Neck Cancer Patients Undergoing Radiochemotherapy: A Prospective Longitudinal Study.

Objective: The present study aimed to assess the impact of low-level laser (LLL) on low salivary flow rate in patients undergoing radiochemotherapy (RT-CT) for head and neck cancer.

Background Data: LLL has shown efficiency in preventing hyposalivation in patients under different pathological conditions, including those undergoing RT-CT.

Methods: During all RT-CT, 17 patients received laser therapy and 10 received clinical care only.

Low-level laser therapy for the prevention of low salivary flow rate after radiotherapy and chemotherapy in patients with head and neck cancer.

Objective: To determine whether low-level laser therapy can prevent salivary hypofunction after radiotherapy and chemotherapy in head and neck cancer patients.

Materials And Methods: We evaluated 23 head and neck cancer patients, of whom 13 received laser therapy and 10 received clinical care only. An InGaAlP laser was used intra-orally (at 660 nm and 40 mW) at a mean dose of 10.

Strategies to evaluate the impact of rectal volume on prostate motion during three-dimensional conformal radiotherapy for prostate cancer.

Objective: To evaluate the rectal volume influence on prostate motion during three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer.

Materials And Methods: Fifty-one patients with prostate cancer underwent a series of three computed tomography scans including an initial planning scan and two subsequent scans during 3D-CRT. The organs of interest were outlined.

Amifostine Increases FAS and Caspase-3 Expression in Colonic Tissue of Irradiated Mice.

Background/aim: The aim of this study was to evaluate the expression of FASL, FAS and FADD and caspase-3 in oesophagus, stomach and colonic tissues of mice irradiated in vivo by immunohistochemistry.

Materials And Methods: A total of 48 adult male C57BL mice were distributed into four groups: Ami(-)/Rad(-): Mice received 0.5 ml of 0.

A synthetic fragment of leptin increase hematopoietic stem cell population and improve its engraftment ability.

Several studies have shown the important actions of cytokine leptin that regulates food intake and energy expenditure. Additionally, the ability to modulate hematopoiesis has also been demonstrated. Previous reports have shown that some synthetic sequences of leptin molecules can activate leptin receptor.

Long-term oral effects in patients treated with radiochemotherapy for head and neck cancer.

Purpose: The purpose of this study is to assess the late oral complications and the role of salivary gland hypofunction in the severity of mucosal reaction in nonsurgical head and neck cancer patients, submitted to radiotherapy with or without chemotherapy.

Methods And Materials: Five hundred fifteen charts from patients treated between 2005 and 2009 were reviewed, and 41 patients met the inclusion criteria. Salivary gland function was assessed using a simplified grading system (GSX) and sialometry.

[Mucositis in head and neck cancer patients undergoing radiochemotherapy].

The objective of present study was to classify oral mucositis according to the Common Toxicity Criterion (CTC) international parameters in head and neck tumor patients simultaneously treated with radio and chemotherapy, and characterize a patient profile in our area, observing the individuals' habits, tumor characteristics, treatment protocol and acute reaction intensity. Fifty patients undergoing simultaneous 66 to 70 Gy megavoltage radiotherapy and cisplatin/carboplatin chemotherapy were evaluated in this study. Weekly evaluations of the degree of mucositis were perfoemed according to CTC, a four-degree ordinal scale; 36% of all patients and 100% of those with diabetes discontinued treatment due to mucositis, showing that this pathology contributes to the severity of mucositis.

Effects of ionizing radiation on bone neoformation: histometric study in Wistar rats tibiae.

Purpose: Comparing the ionizing radiation effects on bone neoformation of rats tibiae previously submitted to radiotherapy with a single dosage of 30Gy with the contralateral tibiae that have received secondary radiation.

Methods: In thirty male Wistar rats, 30 days before surgical procedure when round defects would be created on the bone, the right tibia was irradiated with 30Gy and the left tibia received a calculated secondary radiation dose of 7Gy. Sacrifices were performed after 4, 7, 14, 21, 56 and 84 postoperative days and both tibiae were removed for histological processing.

α-Tocopherol induces hematopoietic stem/progenitor cell expansion and ERK1/2-mediated differentiation.

Tocopherols promote or inhibit growth in different cell types. In the hematopoietic system, the radioprotective property of tocopherols is thought to act through the expansion of primitive hematopoietic cells. However, the mechanisms activated by tocopherols and which HPs are affected remain poorly understood.

The extrinsic apoptotic signaling pathway in gastric adenocarcinomas assessed by tissue microarray.

The purpose of this investigation was to analyze the immunoexpression of FasL, Fas, FADD, cleaved caspase 8, and cleaved caspase 3 in gastric cancer. Formalin-fixed and paraffin-embedded gastric adenocarcinoma tissues from 87 patients, including adjacent normal tissues, were included on tissue microarray by immunohistochemistry. The tumor and the adjacent normal tissues were positive for FasL in 66.

Protracted hypofractionated radiotherapy for Graves' ophthalmopathy: a pilot study of clinical and radiologic response.

Purpose: To evaluate the clinical and radiologic response of patients with Graves' ophthalmopathy given low-dose orbital radiotherapy (RT) with a protracted fractionation.

Methods And Materials: Eighteen patients (36 orbits) received orbital RT with a total dose of 10 Gy, fractionated in 1 Gy once a week over 10 weeks. Of these, 9 patients received steroid therapy as well.

Resident peritoneal inflammatory cells are pivotal in the development of experimental atherosclerosis.

Aim: Based on evidence that ionizing radiation can ameliorate chronic and autoimmune diseases in patients and experimental animals, we investigated the effects of radiation on the induction and development of experimental atherogenesis.

Methods: Male New Zealand rabbits were divided into 5 groups and given an atherogenic diet for 90 days. Peritoneal and thoracic areas (9 Gy) were irradiated on the 1st and 45th days for groups 1 and 2, the 45th day for groups 3 and 4, and not at all for group 5.

Phosphorylation and cytoplasmic localization of MAPK p38 during apoptosis signaling in bone marrow granulocytes of mice irradiated in vivo and the role of amifostine in reducing these effects.

We studied p38 phosphorylation and its intracellular localization during p53 and Puma (a p53 upregulated modulator of apoptosis) apoptotic signaling pathway in bone marrow granulocytes in mice irradiated in vivo and the role of the radioprotector amifostine in ameliorating these responses. Sixty-four C57BL mice were randomly assigned in two non-irradiated (Ami-/rad- and Ami+/rad-) and two irradiated (Ami-/rad+ and Ami+/rad+) groups. Animals received 400mg/kg of amifostine i.

Expression of COX-2 in stomach carcinogenesis.

Background: Gastric cancer is a frequent cause of cancer in Brazil. The understanding of gastric carcinogenesis is not completely known but the progress of the molecular biology has provided that the initiation and progression of gastric cancer process is a consequence of a cumulative series of multiple gene alterations.

Aim: The aim of the study is to investigate the relationship among cytoplasmatic COX-1 and COX-2, Bcl-2 and nuclear P53 in chronic gastritis, metaplasia, and intestinal and gastric cancer.

RTOG criteria to evaluate acute skin reaction and its risk factors in patients with breast cancer submitted to radiotherapy.

Purpose: Evaluate and classify skin reactions through the Radiation Therapy Oncology Group (RTOG) criteria and characterize factors that can intervene in these reactions.

Method: Prospective study, with 86 women submitted to adjuvant breast radiotherapy with a total dose of 5040cGy, in a 6 MeV Linear Accelerator. Personal data were collected and breast size was measured (distance between field separation and breast height).

[Latent TGFbeta1 activation in the lung irradiated in vivo].

Purpose: assess the latent and active TGFb1 localization in the lung, whether or not radiation induces latent TGFbeta1 activation, and the distribution of collagen fibers in the irradiated lung.

Methods: Thirty two C57BL mice were randomly assigned in two groups: GI (non irradiated animals) and GII (irradiated animals). The mice from GII received a single whole - body radiation dose of 7Gy, using a 60Co source at a dose rate of 0.

Amifostine does not prevent activation of TGFbeta1 but induces smad 7 activation in megakaryocytes irradiated in vivo.

Experiments were undertaken to assess the role of amifostine in the activation of latent TGFbeta1 and in the smad proteins cascade (smad 2/3, smad4, smad7), focusing on megakaryocytes, in the bone marrow irradiated in vivo. Non-irradiated megakaryocytes were negative for active TGFbeta1. Immunopositivity to active TGFbeta1 was detected in megakaryocytes 10 days after irradiation in amifostine- treated and untreated marrows.