Behavior, knowledge and perception of risks about sexually transmitted diseases in a group of people over 50 years old

The goal was to analyze the behavior, knowledge and risk perception about sexually transmitted diseases / AIDS (STD/AIDS) in people over 50 years old. 165 public servants at a State Secretary in Mato Grosso, Brazil were interviewed. The chi-square test and logistic regression tests were used for the analysis of risk perception and the behavior and knowledge variables about STD/AIDS. Most of the respondents were female (60.6%), 63.2 had a fixed partner, 72.4% had sexual relations in the past six months, and only 13.3% always wore condoms, with 21.5% being male and 8% female. Perception of risk was associated with non-use of condoms in their last sexual relation (p<0.001) and answering that anyone may acquire a STD/AIDS (p=0.039). The challenge of public policies is to increase actions, directing them to promote the health of the adult and elderly populations, especially regarding sexuality and vulnerability to STD/AIDS.     

Transgenic expression of AQP1 in the fiber cells of AQP0 knockout mouse: Effects on lens transparency

Mutations and knockout of aquaporin 0 (AQP0) result in dominant lens cataract. To date, several functions have been proposed for AQP0; however, two functions, water permeability and cell-to-cell adhesion have been supported by several investigators and only water channel function has been readily authenticated by in vitro and ex vivo studies. Lens shifts protein expression from the more efficient AQP1 in the equatorial epithelial cells to the less efficient water channel, AQP0, in the differentiating secondary fiber cells; perhaps, AQP0 performs a distinctive function. If AQP0 has only water permeability function, can the more efficient water channel AQP1 transgenically expressed in the fiber cells compensate and restore lens transparency in the AQP0 knockout (AQP0^−/−) mouse? To investigate, we generated a transgenic wild-type mouse line expressing AQP1 in the fiber cells using αA-crystallin promoter. These transgenic mice (TgAQP1^+/+) showed increase in fiber cell membrane water permeability without any morphological, anatomical or physiological defects compared to the wild type indicating that the main purpose of the shift in expression from AQP1 to AQP0 may not be to lessen the membrane water permeability. Further, we transgenically expressed AQP1 in the lens fiber cells of AQP0 knockout mouse (TgAQP1^+/+/AQP0^−/−) to determine whether AQP1 could restore AQP0 water channel function and regain lens transparency. Fiber cells of these mice showed 2.6 times more water permeability than the wild type. Transgene AQP1 reduced the severity of lens cataract and prevented dramatic acceleration of cataractogenesis. However, lens fiber cells showed deformities and lack of compact cellular architecture. Loss of lens transparency due to the absence of AQP0 was not completely restored indicating an additional function for AQP0. In vitro studies showed that AQP0 is capable of cell-to-cell adhesion while AQP1 is not. To our knowledge, this is the first report which uses an animal model to demonstrate that AQP0 may have an additional function, possibly cell-to-cell adhesion.     

Computer-assisted detection of pulmonary embolism: evaluation of pulmonary CT angiograms performed in an on-call setting

Purpose

The purpose of the study was to assess the stand-alone performance of computer-assisted detection (CAD) for evaluation of pulmonary CT angiograms (CTPA) performed in an on-call setting.

Methods

In this institutional review board-approved study, we retrospectively included 292 consecutive CTPA performed during night shifts and weekends over a period of 16 months. Original reports were compared with a dedicated CAD system for pulmonary emboli (PE). A reference standard for the presence of PE was established using independent evaluation by two readers and consultation of a third experienced radiologist in discordant cases.

Results

Original reports had described 225 negative studies and 67 positive studies for PE. CAD found PE in seven patients originally reported as negative but identified by independent evaluation: emboli were located in segmental (n?=?2) and subsegmental arteries (n?=?5). The negative predictive value (NPV) of the CAD algorithm was 92% (44/48). On average there were 4.7 false positives (FP) per examination (median 2, range 0–42). In 72% of studies ≤5 FP were found, 13% of studies had ≥10 FP.

Conclusion

CAD identified small emboli originally missed under clinical conditions and found 93% of the isolated subsegmental emboli. On average there were 4.7 FP per examination.     

Continuously moving table MRI with sliding multislice for rectal cancer staging: Image quality and lesion detection

Purpose

To determine image quality and lesion detection of sliding multislice (SMS), a recently developed moving table MRI technique, in patients with rectal cancer.

Materials and methods

Twenty-seven paired SMS (Avanto, Siemens Medical Solutions) and MDCT (Sensation 64, Siemens Medical Solutions) examinations of abdomen and pelvis were performed in patients with rectal cancer and compared for detection of liver, lymph node and bone metastases by two independent observers. A contrast-enhanced, fat saturated 2D gradient echo sequence (TE, 2.0 ms; TR, 102 ms; slice, 5 mm) was acquired with SMS and a standard contrast-enhanced protocol (100 ml @ 2.5 ml/s; slice, 5 mm) was used for abdominal MDCT. Standard of reference consisted of a consensus evaluation of SMS, MDCT, and all available follow-up examinations after a period of 6 months.Artifact burden and image quality of SMS was assessed in comparison to stationary gradient echo sequences obtained in an age-matched group of 27 patients.

Results

Whereas SMS achieved a mean quality score of 3.65 (scale, 0-4) for the liver, representing very good diagnostic properties, strong breathing artifacts in the intestinal region were observed in 19 cases by both observers. The retroperitoneum still achieved a mean quality score of 3.52, although breathing artifacts were noted in 12 and 15 cases (observers 1 and 2, respectively). The sensitivities of SMS to detect hepatic metastases were 91.2% and 94.1% for both observers, respectively, compared to 98.5%/98.5% for MDCT. The sensitivities for lymph node metastases were 87.5%/81.3% for SMS compared to 78.1%/81.3% for MDCT. The sensitivities for bone metastases were 91.7%/100% for SMS compared to 8.3%/16.7% for MDCT.

Conclusion

With slightly reduced image quality in the intestinal region, SMS exhibits equal detection of lymph node and liver metastases compared to MDCT. SMS MRI proved to be superior to MDCT in detection of bone metastases.     

Radiogenomic imaging-linking diagnostic imaging and molecular diagnostics

Radiogenomic imaging refers to the correlation between cancer imaging features and gene expression and is one of the most promising areas within science and medicine. High-throughput biological techniques have reshaped the perspective of biomedical research allowing for fast and efficient assessment of the entire molecular topography of a cell’s physiology providing new insights into human cancers. The use of non-invasive imaging tools for gene expression profiling of solid tumors could serve as a means for linking specific imaging features with specific gene expression patterns thereby allowing for more accurate diagnosis and prognosis and obviating the need for high-risk invasive biopsy procedures. This review focuses on the medical imaging part as one of the main drivers for the development of radiogenomic imaging.     

ApoB100,LDLR-/- mice exhibit reduced electroretinographic response and cholesteryl esters deposits in the retina

PURPOSE: To evaluate the retinal phenotype of 7- and 14-month-old apoB100,LDLR-/- mice, a relevant animal model of lipid metabolism dysfunction. METHODS: Single-flash electroretinograms were obtained from 7- and 14-month-old apoB100,LDLR-/- and control mice fed a standard diet under both scotopic and photopic conditions. Visual cycle retinoids were analyzed in eyes from dark-adapted mice. Retinal and choroidal vascularization was evaluated with scanning laser ophthalmoscopy. Fatty acids were analyzed in the retina. Esterified and free cholesterol was detected in eye cryosections. RESULTS: Scotopic and photopic b-wave amplitudes were significantly reduced in apoB100,LDLR-/- mice compared with control mice at 7 and 14 months of age (between -25% and -35% in 7-month-old animals and between -50% and -60% in 14-month-old animals at 25 cds/m2). Esterified cholesterol was found to accumulate at the basement of the retinal pigment epithelium in apoB100,LDLR-/- mouse eyes. On the contrary, no significant changes in the retinal profile of fatty acids and visual retinoids were observed in apoB100,LDLR-/- mice compared with control animals. CONCLUSIONS: The exclusive expression of apoB100 in LDL receptor-null mouse altered the ERG profile, without modifying the visual cycle of retinoids and led to cholesterol deposition in the retina. These findings clearly suggest the role of cholesterol metabolism in the functioning of the retina and possibly in the etiology of ocular diseases, including age-related macular degeneration.     

Functional characterization of a human aquaporin 0 mutation that leads to a congenital dominant lens cataract

The aquaporin (AQP) transmembrane proteins facilitate the movement of water across the plasma membrane. In the lens, AQP0 is expressed in fiber cells and AQP1 in the epithelium. Recently, two individuals were identified with congenital polymorphic autosomal dominant cataract, due to a single nucleotide base deletion mutation in the lens AQP0. The deletion modified the reading frame resulting in the addition of a premature stop codon. In the present study, we examined the water permeability properties, trafficking and dominant negative effects as well as cytotoxicity due to the mutant AQP0 (Delta213-AQP0) protein. The membrane water permeability (P(w)) of Delta213-AQP0 expressing oocytes (14+/-1 microm/s) was significantly lower than those expressing WT-AQP0 (25+/-3 microm/s). P(w) of water injected control oocytes was 13+/-2 microm/s. Co-expression of WT-AQP0 with Delta213-AQP0 significantly lowered the P(w) (18+/-3 microm/s) compared to WT-AQP0. With or without the EGFP tag, WT-AQP0 protein localized in the plasma membranes of oocytes and cultured cells whereas Delta213-AQP0 was retained in the ER. Forster Resonance Energy Transfer (FRET) showed that WT-AQP0 partly localized with the co-expressed Delta213-AQP0. Co-localization studies suggest that the mutant AQP0 gained its dominant function by trapping the WT-AQP0 in the ER through hetero-oligomerization. Incubating the cells with chemical chaperones, namely, TMAO and DMSO, did not correct the folding/trafficking defects. Cell death in the Delta213-AQP0 expressing cells was due to necrosis caused by the accumulation of Delta213-AQP0 protein in the ER in cytotoxic proportions. The data show that replacement of the distal end of the 6th TM domain and the C-terminal domain of AQP0 due to the deletion mutation resulted in the impairment of cell membrane P(w), localization of the mutant protein in the ER without trafficking to the plasma membrane, and cytotoxicity due to the accumulation of the mutant protein. Cataracts in patients with this mutation might have resulted from the above mentioned consequences.