The reliability of pseudoneglect is task dependent.

Bisection tasks that require individuals to identify the midpoint of a line are often used to assess the presence of biases to spatial attention in both healthy and patient populations. These tasks have helped to uncover a phenomenon called pseudoneglect, a bias towards the left-side of space in healthy individuals. First identified in the tactile domain, pseudoneglect has been subsequently demonstrated in other sensory modalities such as vision. Despite this, the specific reliability of pseudoneglect within individuals across tasks and time has been investigated very little. In this study, we investigated the reliability of response bias within individuals across four separate testing sessions and during three line bisection tasks: landmark, line bisection and tactile rod bisection. Strong reliability was expected within individuals across task and session. Pseudoneglect was found when response bias was averaged across all tasks, for the entire sample. However, individual data showed biases to both left and right, with some participants showing no clear bias, demonstrating individual differences in bias. Significant, cross-session within-individual reliability was found for the landmark and tactile rod bisection tasks respectively, but no significant reliability was observed for the line bisection task. These results highlight the inconsistent nature of pseudoneglect within individuals, particularly across sensory modality. They also provide strong support for the use of the landmark task as the most reliable measure of pseudoneglect.

Configural specificity of the lateral occipital cortex.

While regions of the lateral occipital cortex (LOC) are known to be selective for objects relative to feature-matched controls, it is not known what set of cues or configurations are used to promote this selectivity. Many theories of perceptual organization have emphasized the figure-ground relationship as being especially important in object-level processing. In the present work we studied the role of perceptual organization in eliciting visual evoked potentials from the object selective LOC. To do this, we used two-region stimuli in which the regions were modulated at different temporal frequencies and were comprised of either symmetric or asymmetric arrangements. The asymmetric arrangement produced an unambiguous figure-ground relationship consistent with a smaller figure region surrounded by a larger background, while four different symmetric arrangements resulted in ambiguous figure-ground relationships but still possessed strong kinetic boundaries between the regions. The surrounded figure-ground arrangement evoked greater activity in the LOC relative to first-tier visual areas (V1-V3). Response selectivity in the LOC, however, was not present for the four different types of symmetric stimuli. These results suggest that kinetic texture boundaries alone are not sufficient to trigger selective processing in the LOC, but that the spatial configuration of a figure that is surrounded by a larger background is both necessary and sufficient to selectively activate the LOC.

Clinical spectrum of urinary tract infections due on nontyphoidal Salmonella species.

We performed a retrospective analysis of 28 cases of bacteriuria due to nontyphoidal Salmonella (NTS). Twenty-one patients (75%) had symptoms of urinary tract infection (16, cystitis; 3, pyelonephritis; and 2, renal abscess), and 7 remained asymptomatic. In 24 cases NTS was the sole pathogen isolated from urine. Salmonella enteritidis (a Salmonella subgroup 1 serotype) was the serotype most frequently isolated (16 cases), followed by Salmonella enteritidis serotype typhimurium (5 cases). Sixteen patients (57%) were severely immunocompromised, and 14 (52%) had urologic abnormalities. Recurrence of bacteriuria occurred in four patients. It is suggested that in cases of urinary salmonellosis one must consider the existence of an occult urologic problem or severe immunosuppression.

[Epidemiological profile of non-typhi salmonellosis in a hospital in urban Madrid (1980-1994)]. / Perfil epidemiológico de la salmonelosis no tifoidea en un hospital del área urbana de Madrid (1980-1994).

BACKGROUND: The aim of this study was to describe the epidemiologic profile of non-typhoid salmonellosis at a general hospital in the metropolitan area of Madrid. METHODS: A descriptive and retrospective study of non-typhoid salmonellosis diagnosed at Microbiology Department of Fundación Jiménez Díaz from May 1980 to December 1994 was done. RESULTS: Non-typhoid Salmonella (NTS) was identified in 1796 specimens of 1463 patients, 520 (35.5%) were under 15 years and 943 (64.5%) were over 14 years. The infection was intestinal in 1288 (88%) cases, bacteremic in 129 (8.8%) and focal in 46 (3.1%). The extraintestinal infection was most frequent in patients over 14 years (15.5% versus 5.6%; p < 0.001). From 1987, 34 adults patients with human immunodeficiency virus (HIV) infection developed salmonellosis. The infection was due to Salmonella serogroup B (29.4%) and the extraintestinal manifestations (58.8%) were most frequent in HIV-infected patients than in the control-group (p = 0.004 and p < 0.001, respectively). Salmonella serogroup D was identified in 1041 (71.2%) episodes, and serogroup B in 259 (17.7%). Salmonella serogroup B and C were more resistant to one or more antibiotics than Salmonella serogroup D (p = 0.001). Resistance of NTS (principally Salmonella serogroup B) for one or more antibiotics (particularly ampicillin and chloramphenicol) increased significantly during the period of study (p < 0.001). CONCLUSIONS: The HIV-infected patients had a predisposition to develop extraintestinal Salmonella infections. Resistance of NTS for antibiotics, especially Salmonella serogroup B, has significantly increased during the last years.

Classifying extraintestinal non-typhoid Salmonella infections.

Non-typhoid Salmonella infection in man has been divided into five clinical groups: gastroenteritis, enteric fever, bacteraemia, chronic carrier state and localized infection. This classification has neither pathogenic nor prognostic significance. We retrospectively reviewed the charts of 183 patients with extraintestinal salmonellosis who presented to our institution during a period of 32 years. Patients were classified into four groups: primary bacteraemia (PB), enteritis-associated bacteraemia (secondary bacteraemia) (SB), digestive focal infection (DI) and non-digestive focal infection (NDI). Sex, age, acquisition, underlying disease and outcome were compared between patients with bacteraemia and diseases with focal infection. The differences found between PB and SB were: community acquisition (66% in PB and 85% in SB, p = 0.06) severe immunosuppression (53% in PB and 15% in SB, p < 0.001) and mortality (37% in PB and 3% in SB, p < 0.001). The differences found between NDI and DI were: age over 60 years (45% in NDI and 18% in DI, p < 0.05), severe immunosuppression (51% in NDI and 12% DI, p < 0.001) and associated bacteraemia (38% in NDI and 6% in DI, p < 0.001). This classification of extraintestinal salmonellosis may have pathogenic and prognostic implications, and could help us to understand the clinical significance of this disease.

Changes in susceptibility of Salmonella enteritidis, Salmonella typhimurium, and Salmonella virchow to six antimicrobial agents in a Spanish hospital, 1980-1994.

To determine changes in the susceptibility patterns of Salmonella enteritidis, Salmonella typhimurium, and Salmonella virchow over time, resistance to ampicillin, chloramphenicol, tetracycline, gentamicin, trimethoprim/sulfamethoxazole, and nalidixic acid was studied by the disk diffusion method in 1,024, 191, and 61 clinical isolates of these organisms, respectively. All isolates were recovered from 1980 to 1994 at a hospital in Madrid, Spain. Salmonella enteritidis isolates were less resistant (10.9%) than Salmonella typhimurium (43.5%) and Salmonella virchow (36.1%; p < 0.001). The incidence of resistance of Salmonella enteritidis to ampicillin increased from 2.7% during the period 1980-1982 to 15.6% during 1992-1994 (p < 0.001). The resistance of Salmonella typhimurium to ampicillin, chloramphenicol, and tetracycline increased from 15.2%, 7.6%, and 21.2% respectively in 1980-1982 to 73.3%, 46.7%, and 73.3% in 1992-1994 (p < 0.001). These marked increases in antimicrobial resistance suggest the need for public health interventions, several of which are discussed.

[Osteoarticular infections by Salmonella non-typhi]. / Infecciones osteoarticulares por Salmonella no typhi.

BACKGROUND: The aim of this study was to know the clinical characteristics of osteoarticular infection by Salmonella non typhi (SNT) in Spain. PATIENTS AND METHODS: The medical records of 14 patients with osteoarticular infection by SNT from January 1970 to December 1992 were reviewed. RESULTS: Over the above mentioned 23 years, 1334 patients had been diagnosed with one or more SNT isolations, with 14 (1%) having osteoarticular infection. Seven patients had septic arthritis, 3 osteomyelitis and 4 mixed infection (arthritis and osteomyelitis). Thirteen patients (93%) presented with underlying systemic disease (immunosuppression 12 cases [86%] and hemoglobinopathy 1 case [7%]) and 5 (36%) had predisposing osteoarticular disease. The most commonly affected joint was the knee (9.58%). Involvement was monoarticular in 8 episodes (73%). Out of the 7 cases with osteomyelitis, 4 (57%) were secondary to an articular foci and 3 (43%) were of hematogenic origin. The femur (4 cases, 44%) and the tibia (4 cases, 44%) were the most frequent localizations. On nine occasions (64%) the cultures remained positive 7 days after initiation of antibiotic treatment. Only one patient died as a consequence of the articular infection. CONCLUSIONS: Osteoarticular infection by Salmonella non typhi should take the existence of immune disorders into account.

Clinical significance of primary vs. secondary bacteremia due to nontyphoid Salmonella in patients without AIDS.

We retrospectively reviewed the charts of 51 patients with primary nontyphoid salmonella (NTS) bacteremia who did not have AIDS and who had no history of gastroenteritis and no other identified source of infection. We compared these patients with 58 patients who developed secondary NTS bacteremia following an episode of gastroenteritis. The following characteristics were more frequently associated with primary NTS bacteremia than with secondary NTS bacteremia: age > 60 years (51% vs. 33%; P < .05), glucocorticoid therapy (41% vs. 13%; P < .01), and severe immunosuppression (65% vs. 14%; P < .01). More patients with primary NTS bacteremia had hematologic malignancies, solid tumors, and connective-tissue diseases; in eight cases, primary NTS bacteremia occurred simultaneously with or preceded these disorders. We suggest that the possibility of severe immunosuppression be investigated for patients with salmonella bacteremia who have not had or do not have gastroenteritis.

[The clinical spectrum of focal infection due to nontyphoid Salmonella: 32 years' experience]. / Espectro clínico de la infección focal por Salmonella no typhi: experiencia de 32 años.

BACKGROUND: The aim of this study was to analyze the manifestations of the syndromes which constitute focal infection by Salmonella no typhi (SNT). METHODS: Ninety-one episodes of SNT infections studied over a period of 32 years in the Fundación Jiménez Díaz (Madrid, Spain) were retrospectively analyzed. RESULTS: Of the 1,892 patients with SNT infection studied during this period, 91 (5%) presented some focal form (57 males and 34 females) with a mean age of 49 years (SD +/- 21.6 years). Sixty percent of the episodes were acquired within the community. The localization of the focal infections by SNT was as follows: urologic tract (24%), intraabdominal (20%), soft tissues (16%), respiratory tract (15%), osteoarticular (14%), cardiovascular (10%) and central nervous system (1%). On comparison with the remaining patients, those with urinary, osteoarticular and respiratory infections were found to be the most frequently immunosuppressed (47%) vs 18%, p < 0.01) with a greater frequency of unfavorable evolution (57% vs 15%; p < 0.001). Mortality ranged between 7% for the osteoarticular forms to 64% for the pleuropulmonary forms of infection. CONCLUSIONS: Focal infection by Salmonella no typhi may be localized in any organ usually occurring in immunosuppressed patients or those with predisposing local factors. The osteoarticular, pulmonary, and urologic infections have a particularly unfavorable course and their presence may suggest the existence of immunosuppression.