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M Soltani

Publications and source records attributed to M Soltani.

18 recordsLinked to original sources
PubMed2006

High gamma power is phase-locked to theta oscillations in human neocortex.

We observed robust coupling between the high- and low-frequency bands of ongoing electrical activity in the human brain. In particular, the phase of the low-frequency theta (4 to 8 hertz) rhythm modulates power in the high gamma (80 to 150 hertz) band of the electrocorticogram, with stronger modulation occurring at higher theta amplitudes. Furthermore, different behavioral tasks evoke distinct patterns of theta/high gamma coupling across the cortex. The results indicate that transient coupling between low- and high-frequency brain rhythms coordinates activity in distributed cortical areas, providing a mechanism for effective communication during cognitive processing in humans.

Adult↗
PubMed2005

Variability in the content of Indian generic ciprofloxacin eye drops.

BACKGROUND/AIMS: Under-potent generic antibiotics sold in developing world countries may be contributing to positive selection of resistance organisms and to unpredictability in clinical outcome, leading to a loss of confidence among physicians locally. The objective of this study was to determine whether reports of unpredictable outcome for generic ciprofloxacin antibiotic eye drops in India could be the result of inadequate concentration of preparations sold by pharmacies. METHODS: 130 ciprofloxacin eye drop samples sold by pharmacies were collected from seven locations in north, central, and south India; 30 were randomly selected for testing. All samples were assayed using validated methods of reverse phase chromatography and fluorescence detection at a international antibiotic reference laboratory in the United Kingdom. Results were compared with advertised concentrations within the context of internationally accepted variability ranges. RESULTS: In total, six out of the 30 samples tested had ciprofloxacin concentrations lower than the standard advisory ranges of plus or minus 5% of stated content for 3 mg/ml pharmaceutical preparations. The ciprofloxacin content of these eye drops ranged from -36.4% to -16.1% of the stated content (median -21.73%). 24 out of 30 samples were found to be over the standard advisory ranges of plus or minus 5%, at a median of +19.42% (interquartile range (IQR) +14.28 to +25.13). Intra-batch variability of two selected samples was wide at -22.83% to +33.93% (n=11) and -17.07% to +31.20% (n=12). CONCLUSIONS: Approximately 20% of generic ciprofloxacin eye drops, purchased without prescription in India were under-potent. In a number of preparations the antibiotic content was sufficiently low as to have a potential impact on clinical outcome and possibly lead to the selection of resistant isolates in individual patients. More widespread studies are justified to identify the extent of under-potency of widely used generic antibiotic medications in developing countries.

Anti-Infective Agents↗
PubMed2002

T-cell non-Hodgkin's lymphoma in adults: clinicopathological characteristics, response to treatment and prognostic factors.

T-cell NHL represent 10-15% of all malignant lymphomas making systematic prospective clinical trials difficult. Therefore, the prognostic significance of the T-cell phenotype has been a matter of controversy in recent years. In a retrospective analysis of 681 patients (pts) with NHL accrued from 1992 to 1997 at a single institution, 66 patients with T-cell NHL were identified. According to the REAL classification, histologies were as follows: 28 peripheral T-cell lymphomas (PTCL), 19 large cell anaplastic lymphoma (LCAL), 12 precursor lymphoblastic lymphoma (Lb), and seven AILD. Multiagent anthracycline containing regimens were used as initial therapy in 91% of cases. T-cell NHL represent 9.8% of all NHL patients at our institution accrued over a 6-year period. Overall response rate was 76%, 21% had progressive disease and 3% died during first line treatment. Mean overall survival (OS) was 8.22 +/- 0.94 years. There was a significant difference in OS between the four different histological subgroups (log rank P=0.0288). LCAL: mean OS 11.05 +/- 1.55 years (95% CI 8.00-14.09); LB: mean OS 7.09 +/- 1.40 years (95% CI 4.33-9.84); PTCL: mean 6.62 +/- 1.17 years (95% CI 4.33-8.90); AILD: 1.54 +/- 0.44 years (95% CI 0.67-2.40). OS was also significantly different for patients classified according to the International Prognostic Index (IPI)-score (log rank P = 0.002). Mean OS for patients with low risk, intermediate low risk, intermediate high risk and high risk was 10.46 +/- 1.02, 6.46 +/- 1.79, 4.50 +/- 1.20 and 1.15 +/- 0.46 years, respectively. Univariate analysis (log-rank test) for prognostic factors also revealed elevated LDH, B-symptoms and extranodal involvement as significant factors for OS. The presence of bulky disease (>7.5 cm), advanced stage III/IV and bone marrow involvement did not influence OS. In conclusion, it is evident that histological subtype and IPI-score have a strong prognostic impact on OS in pts with T-cell NHL. Thus, the distribution of risk factors in patients with T-cell NHL may be more important for OS than T-cell histology per se.

Aged↗
PubMed2001

The congruency effect: just what is being learned?

G. H. Bower, S. Thompson-Schill, and E. Tulving (1994) found that when stimulus-response sets in A-B, A-C learning belong to unique categories (congruent-triads), learning appropriate responses appear rapid and memory performance on a modified modified free recall (MMFR) test is enhanced. Bower et al. assumed that category cues protect associations from interpair interference, allowing more rapid learning. However, unlike arbitrary pairs, congruent pairs also allow a reliance on preexperimental associations. As a result, MMFR test performance may not be an unbiased test of what was learned. In the present experiment, free recall (FR) demonstrated that responses were learned approximately equally in all conditions and that the pattern of clustering was compatible with the hypothesis that preexperimental associations continue to play a major role in FR test performance.

Adult↗
PubMed2001

Perceptual load and visuocortical processing: event-related potentials reveal sensory-level selection.

Behavioral evidence suggests that the processing of parafoveal stimuli decreases as the perceptual demands of a task at fixation increase. However, it remains unclear whether or not this effect of perceptual load occurs during initial sensory-level processing at early stages of visuocortical analysis. Using event-related potential measures, we found that increasing the perceptual load of foveal targets led to a significant decrease in the sensory-evoked response to parafoveal stimuli. Moreover, these effects were observed using two different operational definitions of perceptual load. This result indicates that perceptual load affects the flow of information during the initial stages of visuocortical processing.

Adult↗
PubMed2000

Mechanisms of resistance to quinupristin-dalfopristin among isolates of Enterococcus faecium from animals, raw meat, and hospital patients in Western Europe.

Twenty-eight quinupristin-dalfopristin-resistant isolates of Enterococcus faecium from hospital patients and nonhuman sources in European countries were studied. High-level resistance (MICs, >/=32 microg/ml) was associated with the presence of vat(E) (satG) (14 isolates ¿50%) or vat(D) (satA) (6 isolates ¿21%). These genes were not detected in eight (29%) isolates with lower levels of quinupristin-dalfopristin resistance (MICs, 4 to 16 microg/ml). This suggests the presence of further mechanisms of resistance to quinupristin-dalfopristin in E. faecium.

Acetyltransferases↗
PubMed2000

Neural origins of the P300.

A review of the literature investigating the neural origins of detection behavior in humans reveals two event-related potential components, P3a and P3b, each with a distinct neural organization and cognitive function.The P3a is involved in automatic novelty detection and characterized by a more anterior cortical distribution, whereas the P3b is concerned with volitional target detection and has a more posterior cortical distribution. Intracranial investigation, studies with patients with focal brain lesions, and functional neuroimaging (fMRI) studies converge with scalp-recorded event-related potential (ERP) data in suggesting that a widespread cortical network gives rise to both automatic and controlled detection behavior. The main regions consistently attributed to generating detection-related brain activation include the temporal-parietal junction, medial temporal complex, and the lateral prefrontal cortex. The extant human and animal literature addressing the neural networks, neuropharmacological underpinnings, and behavioral significance of the P300 potential will be reviewed.

Animals↗
PubMed1999

Recognition memory for faces: when familiarity supports associative recognition judgments.

Recognition memory for single items can be dissociated from recognition memory for the associations between items. For example, recognition tests for single words produce curvilinear receiver operating characteristics (ROCs), but associative recognition tests for word pairs produce linear ROCs. These dissociations are consistent with dual-process theories of recognition and suggest that associative recognition relies on recollection but that item recognition relies on a combination of recollection and assessments of familiarity. In the present study, we examined associative recognition ROCs for facial stimuli by manipulating the central and external features, in order to determine whether linear ROCs would be observed for stimuli other than arbitrary word pairs. When the faces were presented upright, familiarity estimates were significantly above zero, and the associative ROCs were curvilinear, suggesting that familiarity contributed to associative judgments. However, presenting the faces upside down effectively eliminated the contribution of familiarity to associative recognition, and the ROCs were linear. The results suggest that familiarity can support associative recognition judgments, if the associated components are encoded as a coherent gestalt, as in upright faces.

Adult↗
PubMed1999

Diabetes and hospital morbidity in the Monastir governorship (Tunisia).

Diabetes is a public health problem worldwide. In Tunisia, the rate of prevalence is 3.8% in urban areas and 1.3% in rural areas, whereas the socioeconomic impact of the disease has rarely been investigated. This study conducted in the Monastir health district evaluated the burden of hospital care for diabetes. All admissions for diabetes (973) recorded in the regional morbidity register during 1993 for all public hospitals in the region were taken into consideration. Admission for diabetes represented 5.9% of total admissions and was the first cause of hospitalisation. The university hospital centre received 40% of these patients. The annual hospital rate of diabetes is estimated to be 2.7%, but varies according to the district considered and the age of patients (1.1% for those under 50 years of age and 12.8% for those over 65). The number of days of hospitalization related to diabetes was 10,069, i.e. 7.6% of the total for the district. The mean cost of a single hospitalization is about 251 Tunisian dinars (US$251). Diabetes treatment could be improved and the cost lowered by providing appropriate ambulatory care and health education to reduce hospital admissions.

Aged↗
PubMed1998

Functional conservation of the effector protein translocators PopB/YopB and PopD/YopD of Pseudomonas aeruginosa and Yersinia pseudotuberculosis.

Virulent Yersinia species cause systemic infections in rodents, and Y. pestis is highly pathogenic for humans. Pseudomonas aeruginosa, on the other hand, is an opportunistic pathogen, which normally infects only compromised individuals. Surprisingly, these pathogens both encode highly related contact-dependent secretion systems for the targeting of toxins into eukaryotic cells. In Yersinia, YopB and YopD direct the translocation of the secreted Yop effectors across the target cell membrane. In this study, we have analysed the function of the YopB and YopD homologues, PopB and PopD, encoded by P. aeruginosa. Expression of the pcrGVHpopBD operon in defined translocation-deficient mutants (yopB/yopD) of Yersinia resulted in complete complementation of the cell contact-dependent, YopE-induced cytotoxicity of Y. pseudotuberculosis on HeLa cells. We demonstrated that the complementation fully restored the ability of Y. pseudotuberculosis to translocate the effector molecules YopE and YopH into the HeLa cells. Similar to YopB, PopB induced a lytic effect on infected erythrocytes. The lytic activity induced by PopB could be prevented if the erythrocytes were infected in the presence of sugars larger than 3 nm in diameter, indicating that PopB induced a pore of similar size compared with that induced by YopB. Our findings show that the contact-dependent toxin-targeting mechanisms of Y. pseudotuberculosis and P. aeruginosa are conserved at the molecular level and that the translocator proteins are functionally interchangeable. Based on these similarities, we suggest that the translocation of toxins such as ExoS, ExoT and ExoU by P. aeruginosa across the eukaryotic cell membrane occurs via a pore induced by PopB.

Amino Acid Sequence↗
PubMed1997

Giant intra-adrenal myelolipoma associated with recurrent urinary tract infection.

Adrenal myelolipomas are rare benign tumours that may be identified on routine imaging studies. The association of myelolipomas with obesity, hypertension and malignant tumours has been reported. We describe a giant intra-adrenal myelolipoma in a 40-year-old woman that is the largest asymptomatic tumour of this type documented in the past 10 years. To avoid unnecessary and extensive treatment, the distinction of benign from malignant adrenal tumours or extra-medullary haematopoietic tumour is important, particularly when a small, inactive adrenal mass is found incidentally.

Adrenal Cortex↗
PubMed1997

Biopsy Gleason score: how does it correlate with the final pathological diagnosis in prostate cancer?

OBJECTIVE: To evaluate the role of the Gleason score of needle biopsies of the prostate in predicting the final pathological staging of patients with carcinoma of the prostate treated by radical prostatectomy. PATIENTS AND METHODS: The records of 466 patients with carcinoma of the prostate treated by radical prostatectomy were reviewed, comparing the Gleason scores of the core-needle biopsies with the Gleason score and final pathological staging of the surgical specimens. RESULTS: The biopsy grade was the same as that of the prostatectomy specimen in 54% of the patients. The most common discordance was the upgrading of well-differentiated tumours in 75% of the patients. When the biopsy grade was compared with the surgical pathological stage, 49% of low- and 82% of high-grade lesions in the biopsy had capsular penetration by tumour or locally advanced disease (Stage C and D1). CONCLUSION: Well-differentiated tumours on the biopsy core are not predictive of organ-confined disease, but a poorly differentiated lesion is a good indicator of extracapsular extension of the cancer.

Biopsy, Needle↗
PubMed1991

Echotomographic and serological population-based study of hydatidosis in central Tunisia.

A population-based echotomographic (ECT) and serological survey of hydatidosis was carried out in a high risk community located in Central Tunisia. 1434 subjects over 5 years of age (93.3% of the population in this age range) underwent an abdominal echotomography (ECT) and a serological test (ELISA with confirmation by counterelectrophoresis). The ECT prevalence rate was 3.5% and increased with age reaching 7.7% in the over 39 years age group. Most subjects (96.0%) had liver cyst(s). The serological prevalence rate was 2.9%. A strong agreement was found between ECT and serological results (Kappa test = 0.449). Taking ECT as a reference, the relative specificity and sensitivity of serology were 99.3 and 62.0 respectively. Most ECT positive seronegative subjects had calcified cysts. These results confirm the presence of highly endemic foci of hydatidosis in Central Tunisia, show a good agreement between serological and ECT results at a population level and demonstrate the high feasibility of ECT as a screening technique.

Adolescent↗
PubMed1977

Hematopathology and Pathogenesis of the X-linked recessive lymphoproliferative syndrome.

Subtle immunodeficiency to infectious agents including measles virus and ten Epstein-Barr virus (EBV) has been described in the X-linked recessive lymphoproliferative syndrome. This syndrome has affected six male cousins and possibly another boy. Three brothers died of an infectious mononucleosis syndrome, in a maternal cousin agammaglobulinemia developed three years after infectious mononucleosis, and two half-brothers of the Duncan kindred died of lymphoma of the brain and intestinal tract, respectively. In three of the boys, unusual measles viral infections had developed. Paramyxovirus-like particles suggestive of measles virus were seen at necropsy in the atrophic lymphoid tissue of two boys. Also, numerous plasma cells were seen in the brains, visceral organs and the thymus glands, and thymic-dependent lymphocytes were sparse in lymph nodes and spleen. The abnormal lymphopoiesis in the syndrome probably results from a subtle immunodeficiency, and concurrent measles and EB virus infections.

Agammaglobulinemia↗