IL-1ß-pre-conditioned mesenchymal stem/stromal cells' secretome modulates the inflammatory response and aggrecan deposition in intervertebral disc.

Mesenchymal stem/stromal cells (MSCs) have been increasingly used in clinical trials for low-back pain (LBP) and intervertebral disc (IVD) degeneration with promising results. Their action mechanisms are not fully understood, but they reduce IVD pro-inflammatory markers in a pro-inflammatory/degenerative IVD microenvironment. In this study the therapeutic potential of the MSC secretome, as an alternative cell-free approach for treating degenerated IVDs, was examined. Human bone marrow-derived MSC secretome (MSCsec) was collected after 48 h of preconditioning in IL-1ß (10 ng/mL) and low oxygen (6 % O2), mimicking the degenerative IVD. IL-1ß-pre-conditioning of MSCs increased secretion of pro-inflammatory markers hIL-6, hIL-8, hMCP-1, etc. The therapeutic effect of MSCsec was tested in a pro-inflammatory/degenerative IVD ex vivo model. MSCsec down-regulated IVD gene expression of pro-inflammatory cytokines (bIL-6, bIL-8) and matrix degrading enzyme bMMP1, while bMMP3 and bTIMP2 were up-regulated, at 48 h. After 14 d, MSCsec-treated IVDs revealed increased aggrecan deposition, although no differences in other ECM components were observed. Protein analysis of the MSCsec-treated IVD supernatant revealed a significant increase of CXCL1, MCP-1, MIP-3α, IL-6, IL-8 and GRO α/ß/γ (related to TNF, NOD-like receptor and neutrophil chemotaxis signalling), and a decrease of IFN-γ, IL-10, IL-4, IL-5 and TNF-α (associated with T-cell receptor signalling). MSCsec-treated IVD supernatants did not promote angiogenesis and neurogenesis in vitro. Overall, MSCsec can be a safe therapeutic approach, presenting a strong immunomodulatory role in degenerated IVD while potentiating aggrecan deposition, which can open new perspectives on the use of MSCsec as a cell-based/ cell-free therapeutic approach to LBP.

Development and implementation of a low-cost phantom for quality control in cone beam computed tomography.

A phantom for quality control in cone beam computed tomography (CBCT) scanners was designed and constructed, and a methodology for testing was developed. The phantom had a polymethyl methacrylate structure filled with water and plastic objects that allowed the assessment of parameters related to quality control. The phantom allowed the evaluation of essential parameters in CBCT as well as the evaluation of linear and angular dimensions. The plastics used in the phantom were chosen so that their density and linear attenuation coefficient were similar to those of human facial structures. Three types of CBCT equipment, with two different technological concepts, were evaluated. The results of the assessment of the accuracy of linear and angular dimensions agreed with the existing standards. However, other parameters such as computed tomography number accuracy, uniformity and high-contrast detail did not meet the tolerances established in current regulations or the manufacturer's specifications. The results demonstrate the importance of establishing specific protocols and phantoms, which meet the specificities of CBCT. The practicality of implementation, the quality control test results for the proposed phantom and the consistency of the results using different equipment demonstrate its adequacy.

Development of a phantom and a methodology for evaluation of depth kerma and kerma index for dental cone beam computed tomography.

Basically, all modalities of diagnostic radiology require phantoms suitable for dosimetric evaluations. New technologies frequently arise unaccompanied of tools for dosimetric evaluations and quality control. In this study, a low-cost phantom and a consequent proposed methodology for dosimetric evaluations in cone beam computed tomography (CBCT) were presented. The developed phantom has typical dimensions of the human face, was built in polymethyl methacrylate and filled with water. Three devices with different technological concepts were evaluated and a proposed index, kerma index-height product (PKIH), was defined as an option to the use of air kerma-area product. The results of this study show relatively uniform kerma profiles for scanners with field of views (FOVs) of large diameters and non-uniform for FOVs of small diameters. With regard to the values obtained for the kerma indexes, much higher values were found for the equipment FOVs with small diameter compared with the values of the two other equipment that have larger diameters. The results indicate that (1) there is a need for special phantoms for use in CBCT, (2) the use of P(KA) in the evaluation of protocols on different equipment can lead to false interpretations and (3) the new index is a suitable alternative for the use of P(KA) in CBCT.

Evaluation of personal doses associated with the use of mobile X-rays in a Brazilian hospital.

In Brazilian public hospitals, the number of patients needing assistance is often much greater than the capacity of the hospital. In such situations, medical procedures are performed as quickly as possible, and mobile X-ray equipment is used intensively. This equipment is used for several types of examination, in different areas of the hospital. During the examination procedure, apart from the radiology technicians involved, there are always other people in the room who are also exposed to the radiation scattered by the patient. The objective of this study was to determine the exposure, due to the use of mobile X-ray equipment, of hospital personnel, divided into two categories named 'monitored' and 'non-monitored'. Evaluation of 413 radiographies was performed, the vast majority of them being chest examinations (75 %). During the procedures, specific information was collected to allow measurement in simulated situations. Air kerma rates were measured at different distances from the mobile X-ray equipment using an ionisation chamber and an acrylic phantom with dimensions of 30×30×15 cm(3). From the results, it was possible to estimate the personal dose equivalent received by the individuals in the room during the procedure and to determine the dose maps associated with the use of the mobile X-ray equipment. The results obtained in this study were in accordance with dose limits, but some observed situations were considered critical.

Effective doses in panoramic images from conventional and CBCT equipment.

Dental radiology is being extensively used especially after the consolidation of the dental implant technique. Although dental radiology has always been regarded as a low-dose technique, this scenario has changed with the introduction of volumetric techniques and consequent changes that have resulted from the use of the new technique. To compare dose values related to the use of different technologies used in the acquisition of dental panoramic images, the effective dose associated with this image technique was calculated using two different conversion factors for kerma-area product, P(KA), in the effective dose. Twenty-four pieces of equipment were evaluated and distributed into three categories: (1) 19 units of conventional equipment, (2) 3-cone beam computed tomography equipment (CBCT) which has a specific sensor to obtain panoramic images and (3) 2 items of CBCT equipment which only have sensors for volumetric acquisition, and the obtainment of panoramic images is through software reconstruction. The results show values of PKA and effective dose are higher for devices using digital image receptors. It is concluded that optimisation procedures and critical analysis should always be applied when adopting new technologies.

A voxel-based investigation of regional cerebral blood flow abnormalities in obsessive-compulsive disorder using single photon emission computed tomography (SPECT).

Several functional imaging studies have reported abnormalities of the orbitofrontal and anterior cingulate cortices, striatum and thalamus in obsessive-compulsive disorder (OCD). These studies have often been limited by small patient samples and image analysis methods that rely on region-of-interest (ROI) approaches. We have assessed resting regional cerebral blood flow with 99mTc-ECD SPECT in 26 unmedicated OCD patients and 22 healthy control subjects using the voxel-based Statistical Parametric Mapping method for data analysis. We found a significantly reduced ECD uptake in OCD patients relative to the control subjects in the right lateral orbitofrontal cortex, and in the left dorsal anterior cingulate cortex (P<0.001 two-tailed, uncorrected for multiple comparisons). There were significant positive correlations in the OCD group between the ECD uptake in the left lateral orbitofrontal cortex and ratings for obsessive-compulsive symptoms (OCS), and between the ECD uptake in the right medial orbitofrontal cortex and the ratings for both OCS and depressive symptoms. There were also unpredicted significant ECD uptake increases in the cerebellum in OCD patients, as well as a negative correlation between posterior cingulate ECD uptake and OCS severity (P<0.05, corrected for multiple testing). These results implicate specific subregions of the orbitofrontal and anterior cingulate cortices in the pathophysiology of OCD, as well as suggesting the involvement of other areas not usually included in ROI-based imaging studies. With the incorporation of voxel-based methods and the use of large patient samples, rCBF-SPECT studies may continue to provide valuable information about the functional anatomy of OCD.

Speech rehabilitation after laryngectomy with the amatsu tracheoesophageal shunt.

The Amatsu vocal rehabilitation technique is a tracheoesophageal shunt using a posterior tracheal flap associated with a sphincter made of esophageal muscular wall. Since march 1991 the procedure was done in 33 men and 2 women. ages ranging from 30 to 78 years. Previous radiotherapy, hypopharynx lesions, need for postoperative radiotherapy or use of myocutaneous flap were not considered contraindications. Vocalization was achieved in 76% of our patients and the quality was considered superior than that obtained by the esophageal voice. In only one case the shunt had to be closed surgically because of aspiration. In conclusion, the Amatsu tracheoesophageal shunt is an inexpensive technique that obtain a good quality of vocal rehabilitation in a high percentage of patients, it has few complications and it should be considered for all candidates to a laryngectomy, mainly for those with a good prognosis and a desire to return to their social environment.

Duodenal ulcer and eradication of Helicobacter pylori in a developing country. An 18-month follow-up study.

Forty-eight patients with endoscopically proven duodenal ulcer (DU) and Helicobacter pylori infection detected by 14C-urea breath test (BT) were assigned to 5 days of treatment with furazolidone, metronidazole, and amoxicillin in addition to eventual classical anti-ulcer agents if necessary. Clinical evaluation and BT were repeated at 2, 6, and 18 months after therapy to determine H. pylori eradication or reinfection. Endoscopy was also repeated at 6 and 18 months after treatment to detect DU relapse. In 29 (60%) patients H. pylori had been eradicated at 2 months after therapy, and in 19 (40%) infection persisted. After successful eradication, 6 of 29 (20.7%) were reinfected. All 24 patients who were negative at the 18-month evaluation were asymptomatic, free of anti-ulcer drugs, and with healed ulcers, whereas among the 19 positive patients followed up, 11 (57%) continued to be symptomatic and still using anti-ulcer agents (p less than 0.010), and 10 (53%) showed active ulcers at endoscopy (p less than 0.010). H. pylori eradication is clearly followed by long-term remission of DU. Reinfection may be an additional problem in treating DU patients in developing countries.

Infeccao do parceiro sexual pelo papilomavirus humano / Partner infection by human papillomavirus

Foram examinados 60 parceiros sexuais, de mulheres diagnosticadas como portadoras de infeccao genital pelo papilomavirus, sob protocolo de investigacao. O objetivo era identificar colposcopicamente, lesoes acetobrancas na genitalia externa masculina, biopsia-las e estuda-las histopatologicamente. Predominava como sinal patognomonico, a coilocitose celular. A biopsia foi positiva em 77,1 por cento e negativa em 22,9 por cento. Os resultados da pesquisa fecham a hipotese de que o parceiro sexual masculino e, de fato, um elemento de risco, agindo como transmissor de infeccao genital pelo papilomavirus humano.