Interactive MR imaging-guided biopsy and aspiration with a modified clinical C-arm system

OBJECTIVE: This investigation was performed to test the hypotheses that interactive guidance of MR image acquisition during needle-directed procedures using a clinical 0.2-T C-arm open MR imaging system integrated with a frameless optically linked stereotaxy system is feasible, and that procedure times can be sufficiently short to be well tolerated by the patient. SUBJECTS AND METHODS: One hundred six MR-guided procedures were performed in 86 patients (ranging in age from 5 months to 88 years) using a clinical C-arm imaging system supplemented with an in-room RF-shielded liquid crystal display monitor, a frameless stereotaxy system, rapid gradient-echo sequences for needle guidance, and MR-compatible monitoring and surgical lighting equipment. We performed 50 biopsies and aspirations of the head and neck in 37 patients, 23 biopsies of musculoskeletal lesions in 22 patients, 16 biopsies of abdominal sites in 10 patients, six biopsies of the thoracolumbar spine or sacrum in six patients, and 11 shoulder joint injections for MR arthrography in 11 patients, in addition to 38 MR arthrographic injections on the same imaging system described in a previous report. Tissue sampling included fine-needle aspiration (n = 90) and cutting needle core biopsy (n = 41). Thirty-five patients underwent both procedures. Procedures were evaluated for success of needle placement, procedure time, and complications. RESULTS: Needle placement was successful in all cases, and no complications occurred. Tissue was sufficient for pathologic diagnosis for all but eight patients. Passes per patient averaged 2.1. For fine-needle aspiration, instrument time averaged 7 min 42 sec per pass, cutting needle core biopsy averaged 6 min 24 sec, and shoulder injection averaged 8 min. CONCLUSION: MR imaging guidance for needle procedures on a clinical 0.2-T C-arm system with supplemental interventional accessories is feasible, with relatively rapid needle placement.     

Inverted papilloma of the nasal cavity and the paranasal sinuses: using CT for primary diagnosis and follow-up

OBJECTIVE: Morphologic criteria for the diagnosis of primary and recurrent inverted papilloma as revealed on CT were evaluated in a large series. MATERIALS AND METHODS: Findings of 121 CT examinations that had been performed in 32 patients with histologically proven inverted papilloma were retrospectively analyzed using the following morphologic criteria: localization, size, surface configuration, and bony changes. RESULTS: Unilateral tumor localization involving the lateral nasal wall and the middle meatus was the feature that best correlated with the finding of primary inverted papilloma. A lobulated surface pattern was another typical sign, which was revealed on 19 of the 29 CT scans of patients with primary inverted papilloma. Although tumor localization and the finding of a newly grown soft-tissue mass were less reliable criteria to differentiate between recurrent inverted papilloma and postoperative complications or concomitant inflammatory disease, a lobulated surface pattern was seen on 26 of the 28 CT scans of patients with tumor recurrence but on only three of the 64 follow-up CT scans of patients without recurrent inverted papilloma. CONCLUSION: A unilateral mass within the nasal cavity or paranasal sinuses with a surface configuration that appears lobulated on CT is, to our knowledge, a new sign that strongly suggests inverted papilloma as a primary diagnosis and also suggests inverted papilloma in patients with tumor recurrence.     

Assessment of cell surface glycoconjugates in normal, benign and malignant human nasal mucosa

Aberrant glycosylation of proteins is a common characteristic of neoplastic changes. No reports exist relating cell surface glycoconjugates to normal, benign and malignant human nasal mucosa. Using lectin affinity histochemistry, glycoconjugate reactivities for peanut agglutinin (PNA), concanavalin A (Con A), Griffonia simplicifolia agglutinin II (GSA-II), soy bean agglutinin (SBA) and Ulex europaeus agglutinin l (UEA-I) were analysed in the following groups: normal, benign (polyp, papilloma, and inverted papilloma) and malignant (squamous cell carcinoma (SCC) alone, SCC arising in inverted papilloma, and adenocarcinoma). The positive rate of lectin staining was evaluated using a quantitative AutoCAD programme. We correlated glycoconjugate expression to clinical features, diagnosis, and malignant transformation. The positive rate of PNA after neuraminidase pre-treatment (NA-PNA) staining was higher in inverted papilloma, while all-negative in polyp and papilloma. NA-PNA staining may be used as a differential diagnostic tool. Both inverted papilloma portions and SCC portions of the SCC synchronized with inverted papilloma subjects showed similar Con A and NA-PNA staining patterns. The biological characteristics define inverted papilloma as a pre-malignant neoplasm. The positive rate of PNA staining was significantly higher in inverted papilloma (inverted papilloma transformed to SCC) compared to inverted papilloma alone. Hence, PNA staining may predict malignant transformation of inverted papilloma. However, further investigations are required to prove this possibly worthwhile prognostic marker.     

Anatomic variants of the internal carotid artery as differential parapharyngeal space-occupying lesions diagnosis

AIMS: To study the prevalence of high risk oncogenic human papillomaviruses (HPV) in inverted papilloma and papillary transitional cell carcinoma of the bladder. METHODS: Ten cases of inverted papilloma and 20 cases of papillary transitional cell carcinoma of the bladder from Chinese patients in Hong Kong were examined for the presence of HPV type 6, 11, 16, 18, 31, and 33 genomes using the polymerase chain reaction and HPV type specific primer probe combinations on paraffin wax embedded biopsy specimens. RESULTS: Of the 10 cases of inverted papilloma, cases 1 and 6 showed the presence of HPV types 16 and 18, respectively. Six of the 20 papillary transitional cell carcinomas were positive for HPV type 18. The other HPV types were not detected. CONCLUSIONS: HPV type 18 was found in 60% and 30% of cases of inverted papilloma and papillary transitional cell carcinoma of the bladder, respectively. These tumours were rarely associated with HPV types 6, 11, 16, 31, and 33. The role of HPV type 18 in oncogenesis of inverted papilloma and transitional cell carcinoma of the bladder requires further studies.     

Face detection in peripheral vision: do faces pop out?

We examined whether faces can produce a 'pop-out' effect in visual search tasks. In the first experiment, subjects' eye movements and search latencies were measured while they viewed a display containing a target face amidst distractors. Targets were upright or inverted faces presented with seven others of the opposite polarity as an 'around-the-clock' display. Face images were either photographic or 'feature only', with the outline removed. Naive subjects were poor at locating an upright face from an array of inverted faces, but performance improved with practice. In the second experiment, we investigated systematically how training improved performance. Prior to testing, subjects were practised on locating either upright or inverted faces. All subjects benefited from training. Subjects practised on upright faces were faster and more accurate at locating upright target faces than inverted. Subjects practised on inverted faces showed no difference between upright and inverted targets. In the third experiment, faces with 'jumbled' features were used as distractors, and this resulted in the same pattern of findings. We conclude that there is no direct rapid 'pop-out' effect for faces. However, the findings demonstrate that, in peripheral vision, upright faces show a processing advantage over inverted faces.     

C1 inhibitor gene sequence facilitates frameshift mutations

Mutations disrupting the function or production of C1 inhibitor cause the disease hereditary angioneurotic edema. Patient mutations identified an imperfect inverted repeat sequence that was postulated to play a mechanistic role in the mutations. To test this hypothesis, the inverted repeat was cloned into the chloramphenicol acetyltransferase gene in pBR325 and its mutation rate was studied in four bacterial strains. These strains were selected to assay the effects of recombination and superhelical tension on mutation frequency. Mutations that revert bacteria to chloramphenicol resistance (Cmr) were scored. Both pairs of isogenic strains had reversion frequencies of approximately 10(-8). These rare reversion events in bacteria were most often a frameshift that involved the imperfect inverted repeat with a deletion or a tandem duplication, an event very similar to the human mutations. Increased DNA superhelical tension, which would be expected to enhance cruciform extrusion, did not accentuate mutagenesis. This finding suggests that the imperfect inverted repeat may form a stem-loop structure in the single-stranded DNA created by the duplex DNA melting prior to replication. Models explaining the slippage can be drawn using the lagging strand of the replication fork. In this model, the formation of a stem-loop structure is responsible for bringing the end of the deletion or duplication into close proximity.     

Endovascular grafts for noninfected aortoiliac anastomotic aneurysms

PURPOSE: This report describes our experience with endovascular repair of aortic and iliac anastomotic aneurysms. METHODS: Between June 1994 and March 1996, 12 noninfected aortic or iliac anastomotic aneurysms in 10 patients who had serious comorbid medical conditions that precluded or made difficult standard operative repair were treated using endovascular grafts. No patient in this study had a history of fever, leukocytosis, or computed tomographic evidence of a periprosthetic fluid collection that was suggestive of infection of the original graft. Endovascular grafts composed of polytetrafluoroethylene and balloon-expandable stents were introduced through a femoral arteriotomy and were placed using over-the-wire techniques under C-arm fluoroscopic guidance. RESULTS: Endovascular grafts were successfully inserted in all patients with aortic or iliac anastomotic aneurysms. There were no procedure-related deaths, and complications included one postprocedure wound hematoma and one perioperative myocardial infarction. Graft patency has been maintained for a mean of 16.1 months, with no computed tomographic evidence of aneurysmal enlargement or perigraft leakage. CONCLUSIONS: Endovascular grafts appear to be a safe and effective technique for excluding some noninfected aortoiliac anastomotic aneurysms in high-risk patients and may become a treatment option in all patients who have clinically significant lesions.     

On the recognition of words with inverted letters.

Conducted 2 experiments in which 24 Ss were asked to identify words with all or some of their letters inverted. The experiments differed only in the explicitness of the instructions given to Ss. In some cases the letters appearing upside down were inverted as 1 unit, and in other cases they were inverted by letter. It was found that when all the letters were inverted, recognition time was faster for unit inversion. When just a few of the letters in the words were inverted, recognition time was shorter when the inversion was letter by letter rather than by unit. Data are consistent with a model that assumes that when the stimulus is homogeneously misoriented unit correction is applied, and when such homogeneity does not exist piecemeal correction is applied. (French abstract) (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does face inversion change spatial frequency tuning?

The authors examined spatial frequency (SF) tuning of upright and inverted face identification using an SF variant of the Bubbles technique (F. Gosselin & P. G. Schyns, 2001). In Experiment 1, they validated the SF Bubbles technique in a plaid detection task. In Experiments 2a–c, the SFs used for identifying upright and inverted inner facial features were investigated. Although a clear inversion effect was present (mean accuracy was 24% higher and response times 455 ms shorter for upright faces), SF tunings were remarkably similar in both orientation conditions (mean r = .98; an SF band of 1.9 octaves centered at 9.8 cycles per face width for faces of about 6°). In Experiments 3a and b, the authors demonstrated that their technique is sensitive to both subtle bottom-up and top-down induced changes in SF tuning, suggesting that the null results of Experiments 2a–c are real. The most parsimonious explanation of the findings is provided by the quantitative account of the face inversion effect: The same information is used for identifying upright and inverted inner facial features, but processing has greater sensitivity with the former. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Face and mouth inversion effects on visual and audiovisual speech perception.

Three experiments examined whether image manipulations known to disrupt face perception also disrupt visual speech perception. Research has shown that an upright face with an inverted mouth looks strikingly grotesque whereas an inverted face and an inverted face containing an upright mouth look relatively normal. The current study examined whether a similar sensitivity to upright facial context plays a role in visual speech perception. Visual and audiovisual syllable identification tasks were tested under 4 presentation conditions: upright face-upright mouth, inverted face-inverted mouth, inverted face-upright mouth, and upright face-inverted mouth. Results revealed that for some visual syllables only the upright face-inverted mouth image disrupted identification. These results suggest that upright facial context can play a role in visual speech perception. A follow-up experiment testing isolated mouths supported this conclusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fearful expressions gain preferential access to awareness during continuous flash suppression.

Rapid evaluation of ecologically relevant stimuli may lead to their preferential access to awareness. Continuous flash suppression allows assessment of affective processing under conditions in which stimuli have been rendered invisible due to the strongly suppressive nature of dynamic noise relative to static images. The authors investigated whether fearful expressions emerge from suppression into awareness more quickly than images of neutral or happy expressions. Fearful faces were consistently detected faster than neutral or happy faces. Responses to inverted faces were slower than those to upright faces but showed the same effect of emotional expression, suggesting that some key feature or features in the inverted faces remained salient. When using stimuli solely representing the eyes, a similar bias for detecting fear emerged, implicating the importance of information from the eyes in the preconscious processing of fear expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The temporal dynamics of reading: a PET study

The temporal dynamics of evoked brain responses are normally characterized using electrophysiological techniques but the positron emission tomography study presented here revealed a temporal aspect of reading by correlating the duration a word remained in the visual field with evoked haemodynamic response. Three distinct types of effects were observed: in visual processing areas, there were linear increases in activity with duration suggesting that visual processing endures throughout the time the stimulus remains in the visual field. In right hemisphere areas, there were monotonic decreases in activity with increased duration which we relate to decreased attention for longer stimulus durations. In left hemisphere word processing areas there were inverted U-shaped dependencies between activity and word duration indicating that, after 400-600 ms, activity in word processing areas is progressively reduced if the word remains in the visual field. We conclude that these inverted U effects in left hemisphere language areas reflect the temporal dynamics of visual word processing and we highlight the implication of these effects for the design of activation studies involving reading.     

A cruciform-dumbbell model for inverted dimer formation mediated by inverted repeats

Small inverted repeats (small palindromes) on plasmids have been shown to mediate a recombinational rearrangement event in Escherichia coli leading to the formation of inverted dimers (giant palindromes). This recombinational rearrangement event is efficient and independent of RecA and RecBCD. In this report, we propose a cruciform-dumbbell model to explain the inverted dimer formation mediated by inverted repeats. In this model, the inverted repeats promote the formation of a DNA cruciform which is processed by an endonuclease into a linear DNA with two hairpin loops at its ends. Upon DNA replication, this linear dumbbell-like DNA is then converted to the inverted dimer. In support of this model, linear dumbbell DNA molecules with unidirectional origin of DNA replication (ColE1 ori ) have been constructed and shown to transform E.coli efficiently resulting in the formation of the inverted dimer. The ability of linear dumbbell DNA to transform E.coli suggests that the terminal loops may be important in bypassing the requirement of DNA supercoiling for initiation of replication of the ColE1 ori.     

Preventing the generation of artifacts during peptide map analysis of recombinant human insulin-like growth factor-I

OBJECTIVE: To compare two methods of connecting the ureters to an ileocystoplasty. PATIENTS AND METHODS: Eighteen men with bladder cancer underwent radical cystoprostatectomy and a further two had a subtotal cystectomy, all with immediate orthotopic bladder replacement by ileocystoplasty. In 10 patients, the ureters were connected to the neobladder by a length of ileum with an inverted nipple valve, while in the other 10 the ureters were implanted directly using a serosal tunnel. Post-operatively, the upper tracts were examined by intravenous urography and the neobladder by cystography before removal of the catheter. RESULTS: The direct implantation technique used 15 cm less ileum and took a mean of 1 h less operating time to complete. The kidneys and ureters remained normal in all patients except one, who had a subtotal cystectomy and developed severe hydronephrosis and hydroureter with acute renal failure when the inverted nipple valve became everted. CONCLUSIONS: Whilst both techniques gave satisfactory results, direct implantation is more economical in the length of ileum used and in operating time.     

Changes of auditory word discrimination induced by inversion of the visual field.

Examined auditory discrimination in normal hospital staff members during induced visual conflict. Discrimination of words accompanied by background noise was measured at 6 speech-signal-noise intensity levels during preexperimental (normal vision), experimental (inverted vision), and postexperimental (normal vision) periods. A control condition (no inverted vision) served as a check for the possible effects of practice or fatigue. Significant losses of word discrimination occurred only in the inverted vision condition. Discrimination losses occurred at all intensity levels in which speech was accompanied by noise, prior to walking in the inverted vision condition, following a walking period, and after removal of inversion eyepieces. Results are attributed to a process of visually induced conflict in which Ss were unable to decenter the altered contents of vision. Affinities between reports of induced alterations of experience and pathological alterations of experience are discussed. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Encoding Operations and Recognition Memory for Faces.

Two experiments examined the effects of encoding operations on forced-choice recognition memory for upright and inverted photographs of faces. In Experiment 1, with distractors closely matched to targets, performance was better on upright than on inverted faces, but was unaffected by whether subjects judged faces for distinctive features, distinctive traits or distinctive expressions. In Experiment 2, where distractors were either absent or weakly matched to distractors, accuracy was again higher on upright than on inverted faces, and was similar for the three encoding operations on upright faces. In contrast, it was poorer for distinctive expression judgments than for distinctive feature or for distinctive trait judgments on inverted faces. These results support Winograd's (1981) claim that distinctive feature and distinctive trait judgments both lead to the isolation of distinctive features. However, it was argued that distinctive expression judgments led to configural processing that was disrupted by inversion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of the genomic short regions of a vaccine strain (SA-2) and a virulent strain (CSW-1) of infectious laryngotracheitis virus (Gallid herpesvirus 1)

Restriction enzyme linkage maps were produced for the genomic short region of the virulent infectious laryngotracheitis virus (CSW-1 strain). After comparison with the equivalent restriction enzyme linkage maps for the infectious laryngotracheitis virus SA-2 strain (a vaccine strain), it was determined that the maps for the short regions of the two strains were identical, apart from a single section in each of the inverted terminal repeats. Each inverted terminal repeat of the SA-2 strain was discovered to contain 467 base pairs more DNA than the CSW-1 strain's inverted terminal repeats. This extra DNA was more precisely mapped entirely within the EcoRI fragments D and d of SA-2, which were found to form part of the SmaI fragments U and P of SA-2 and Q and b of SA-2 and to contain one SmaI restriction enzyme site.     

Memory for pictures of upright and inverted primate faces in humans (Homo sapiens), squirrel monkeys (Saimiri sciureus), and pigeons (Columba livia).

Humans (Homo sapiens) and squirrel monkeys (Saimiri sciureus) were tested for memory of upright and inverted primate faces. Working memory was tested in Exp 1 with a delayed matching-to-sample procedure, and reference memory was examined in Exp 2 by requiring Ss to learn to discriminate between successive pairs of upright or inverted pictures. Both human and monkey subjects showed better working memory for upright than for inverted human faces and better reference memory for upright than for inverted human and great ape faces. In Exp 3, reference memory tests with pigeons (Columba livia) showed no effects of inversion on rate of learning with face pictures. We argue that these findings cannot be explained easily by an individual primate's lifetime experiences with primate faces. We suggest that similar evolved mechanisms for primate face recognition in people and monkeys are responsible for the pattern of data reported. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The writing performance of inverted and noninverted right- and left-handers.

Compared the writing performance of 33 inverted and 37 noninverted left-handed and right-handed writers (undergraduates). Inverted writers wrote as quickly and as well as noninverted writers when writing with the preferred writing posture but were superior to the latter group when performances with the nonpreferred posture were compared. There was no evidence that left-handers with either writing position were faster with the nonpreferred hand, in direct contradiction to R. Gregory and J. Paul's (see record 1981-11652-001) frequently cited claim that inverted left-handers write faster with the nonpreferred hand. Findings are also related to the J. Levy and M. L. Reid (see record 1977-05149-001) model of writing posture and cerebral organization. Results question attempts by educators to discourage use of the inverted writing posture. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)