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PubMed1994

Measuring the poles of negative and positive mood using the Positive Affect Negative Affect Schedule and Activation Deactivation Adjective Check List.

The Positive Affect Negative Affect Schedule (PANAS) has become one of the most widely used measures of mood. It was developed from research using responses to adjective checklists as empirical evidence for the two independent, bipolar factor model of mood. However, when scores on the PANAS were factor analyzed with those from another mood checklist, Thayer's Activation Deactivation Adjective Check List, the PANAS represented only half of the model proposed by Watson and Tellegen (1985) by not containing adjectives representing the lower poles of positive and negative affect.

Adolescent↗

PubMed1999

Dissociation of the mismatch negativity and processing negativity attentional waveforms with nitrous oxide.

In Näätänen's model of early attention, the role of arousal in influencing the permanent feature detection system (indexed by mismatch negativity [MMN]) and the temporary feature-detection system (indexed by processing negativity [PN]) is unclear. To address this question, we investigated the effects of the anesthetic gas nitrous oxide (N2O) on the MMN and PN. Ten subjects performed a dichotic listening task in which discrimination difficulty and breathing mixture (air or 25% N2O) were manipulated factorially. MMN, PN, N1 and P300 at Fz, Cz, and Pz, as well as reaction time (RT), were measured. N2O had no effect on the PN, but decreased MMN amplitude. As expected, N2O decreased the amplitude of the N1 and P300 and increased the latency of the P300 and RT. The dissociation of MMN and PN by N2O suggests that this agent decreases the ability to detect automatic stimulus change without affecting voluntary selective attention. We interpret these results as indicating that arousal has multidimensional effects on early attentional mechanisms. These dimensions can be differentiated chemically by neurotransmitters in the reticular formation of the brain.

Adult↗

PubMed2000

Epileptic negative myoclonus and brief asymmetric tonic seizures. A supplementary sensorimotor area involvement for both negative and positive motor phenomena.

Epileptic negative myoclonus (ENM) is an epileptic motor dysfunction characterised by brief lapses of postural tone provoked by paroxysmal cortical discharges. We report the electrophysiological and video-polygraphic findings in a patient presenting with the unusual association of ENM and brief asymmetric tonic-postural seizures of cryptogenetic origin. Focal EMG silent periods in the left deltoid muscle (mean duration 81.2 +/- 16.4 ms), time-locked with vertex spikes were present. The time lag between spikes and ENM was 33.1 +/- 4.6 ms. We suggest the involvement of mesial frontal areas in the genesis of both negative and positive motor phenomena.

Adolescent↗

PubMed1999

[Clinical applications of late negative evoked potentials--contingent negative variation (CNV)].

Contingent negative variation /CNV/ is a slow negative potential described first in 1964 by Walter et al. It is a correlate of cerebral activity in the frontal lobes connected with expectation of stimulus and frontal cortex preparation for the stimulus to come. CNV develops in the time between the warning signal /S1/ and the commanding signal /S2/. CNV contains two main components connected directly with brain function: the first one, so called early component, is connected with the process of orientation or warning /it is called also orientation wave/, the second one /late component/ is connected with the preparation for movement /expectation wave or preparatory wave/. The clinical application of CNV is for the evaluation of the correlation of potential changes with changes in cognitive functions occurring in various diseases. Numerous studies reported recently have confirmed the applicability of CNV on the diagnosis of dementia, Parkinson's disease, epilepsy, schizophrenia, anxiety states, chronic pains, including migraine.

Anxiety Disorders↗

PubMed1992

[Possible pathogenesis of giant negative T and negative U waves in hypertrophic cardiomyopathy: a report of two cases].

Giant negative T (GNT) and negative U (NU) waves are electrocardiographic findings which have been frequently observed in hypertrophic cardiomyopathy (HCM). Here we report 2 cases. For the first patient, electrocardiographic and left ventriculographic studies before and after the development of GNT and NU waves and left ventricular high voltage during the follow-up period were performed. For the second patient, electrocardiographic and echocardiographic findings were obtained before and after onset of posterior myocardial infarction. In the first patient, posterior papillary muscle hypertrophy was evident on left ventriculography after appearance of GNT and NU waves. In the second patient, both GNT and NU waves disappeared after posterior myocardial infarction. Two-dimensional echocardiograms demonstrated akinesis in the posterior wall, including the posterior papillary muscle, after 8 weeks of posterior infarction. Therefore, we suggest that apical hypertrophy, especially of the posterior papillary muscle, may play an important role in the pathogenesis of GNT and NU waves in HCM.

Aged↗

PubMed1975

Establishment and characterization of an Epstein-Barr virus (EBC)-negative lymphoblastoid B cell line (BJA-B) from an exceptional, EBV-genome-negative African Burkitt's lymphoma.

An Epstein-Barr virus (EBV)-negative lymphoblastoid cell line (LCL), BJA-B, was established from an African Burkitt's lymphoma (BL) which contained no detectable EBV DNA and did not express the EBV specified antigen EBNA, BJA-B cells grow in typically large, flat clumps. All carry surface-bound immunoglobulins, a B lymphocyte marker, and do not form rosettes with sheep erythrocytes. After infection of BJA-B cells by EBV the infected cells may produce either EBV-determined nuclear antigen (EBNA) or both EBNA and early antigen (EA), depending on the strain of EBV. The homogeneity of the BJA-B cell population with respect to immunological and isoenzyme markers and size suggests a clonal origin of the line. BJA-B is the first EBV-negative LCL established from an African Burkitt's lymphoma and demonstrates that an EBV-independent continuous B cell line can be established "in vitro" from other than leukemia or myeloma cells.

Antigens, Viral↗

PubMed1991

Negative strand RNA viruses come of age. Negative Strand RNA Virus Transcription and Replication sponsored by the Fundación Juan March, Madrid, Spain, April 22-24, 1991.

The recent development of several systems that facilitate manipulation of the nucleotide sequences of negative strand RNA viruses and examination of the effects of these changes in vivo has enabled great progress in the study of these fascinating organisms. Such studies are leading to a greater understanding of the role of viral nucleotide sequences and viral (and sometimes cellular) proteins in the control of negative strand RNA virus replication and transcription. This Fundación Juan March Workshop provided an excellent opportunity for extensive discussion and exchange of ideas on just how far the research on these viruses has gone, and for contemplating the paths that future inquiries will take.

RNA Viruses↗

PubMed1994

[Gram-negative rods: antibacterial agents effective on gram-negative rods].

Some kinds of gram-negative rods cause serious infections in the compromised hosts. The species most frequently isolated in big hospitals are P. aeruginosa, E. coli, K. pneumoniae, E. cloacae, S. marcescens, and H. influenzae. Among these species. P. aeruginosa, E. cloacae and S. marcescens show resistance to many antibacterial agents. The aminoglycoside, such as gentamicin, is effective against these strains but resistant strains are detected at a high frequency for P. aeruginosa. Resistant strains to new quinolones are isolated for both S. marcescens and P. aeruginosa. The third generation cephems are effective against these species but they easily acquire resistance to these drugs. Imipenem and cefclidin are effective and a few resistant strains to the drugs are already detectable in gram-negative rods.

Anti-Bacterial Agents↗

PubMed1996

Oct-1 transcription factor is a negative regulator of rat CYP1A1 expression via an octamer sequence in its negative regulatory element.

The rat CYP1A1 negative regulatory element (NRE) contains AP-1 and Oct-1 motifs at -808 to -788 bp. The CYP1A1 sequence from -813 to -779 bp and an identical sequence bearing a point mutation in the octamer motif were synthesized. Gel mobility shift assays showed the formation of two complexes with the wild-type CYP1A1 sequence and nuclear extracts from H4IIE and HepG2 hepatoma cells and from rat liver. The formation of the major complex was significantly reduced with the mutant octamer-containing oligomer and was specifically competed by an Oct-1 oligodeoxyribonucleotide. The addition of Oct-1 antibody caused a supershift of the major complex. The presence of the wild-type sequence, but not the mutant octamer sequence, caused a 3-fold decrease in SV40 enhancerless promoter activity in transfected HepG2 cells. Co-transfection of an Oct-1 expression vector with rat CYP1A1 NRE octamer-containing, promoter/reporter gene constructs specifically further decreased promoter activity of the wild-type octamer-containing constructs in HepG2 cells. The results indicate that Oct-1 binds to the rat CYP1A1 promoter NRE and is a negative regulator of rat CYP1A1 expression.

Animals↗

PubMed1999

Bacteremia by gram-negative bacilli in patients with hematologic malignancies. Comparison of the clinical presentation and outcome of infections by enterobacteria and non-glucose-fermenting gram-negative bacilli.

To compare the characteristics of bacteremic infections by different aerobic gram-negative bacilli (GNB) in patients with hematologic malignancies, we studied 54 consecutive monomicrobial bacteremias by Enterobacteriaceae (EB), 15 by Pseudomonas aeruginosa, 43 by other non-glucose-fermenting GNB (NGFGNB) and 11 by other GNB. Patients with EB and P. aeruginosa bacteremia usually developed the infection after intensive chemotherapy for leukemia or during a hematopoietic stem cell transplantation, while most infections in outpatients off therapy were due to NGFGNB. A significant proportion of bacteremias by EB (37%) and P. aeruginosa (40%) were accompanied by severe morbidity (septic shock, pneumonia or deep-seated organ infections) vs. only 7% of other NGFGNB (p < 0.01). Most infections by these latter bacteria were catheter-related bacteremias (80 vs. 2% of EB, p < 0.005), while most EB infections (61%) were uncomplicated bacteremias of unknown source (vs. 14% of other NGFGNB, p < 0.005). Appropriate antibiotics alone cured 98% of EB and 73% of P. aeruginosa bacteremias but only 26% of other NGFGNB (p < 0.005 for both differences), which were cured by catheter removal in 70%, usually after failure of antibiotic treatment. In conclusion, our results suggest that there are significant differences in the patient populations and clinical characteristics of bacteremic infections by the classic GNB (EB and P. aeruginosa) and the new NGFGNB in adults with hematologic malignancies.

Adolescent↗

PubMed1997

A family of gram-negative bacterial outer membrane factors that function in the export of proteins, carbohydrates, drugs and heavy metals from gram-negative bacteria.

Gram-negative bacteria have evolved transport complexes that export macromolecules and toxic substances across the two membranes of the cell envelope in a single energy coupled step. The process requires (1) a cytoplasmic membrane export system, (2) a membrane fusion protein (MFP), and (3) an outer membrane factor (OMF). Families comprising the former two constituents have been described previously. We here present an analysis of the phylogenetic and structural characteristics of the OMF family. Twenty-one members of this family have been identified, and based on available evidence, they function in conjunction with ABC, RND, MFS and/or other types of cytoplasmic transport systems. OMFs exhibit fairly uniform sizes (398-495 residues with two exceptions), and based on computational analyses, they may form beta-barrel structures consisting of up to 16 beta-strands. Phylogenetic analyses reveal that while the MFPs cluster in accordance with the type of cytoplasmic membrane transport systems with which they function, OMFs do not. We conclude that OMFs probably comprise a family of outer membrane porin-type proteins of uniform structure which did not coevolve with their cognate cytoplasmic membrane transport systems.

Bacterial Outer Membrane Proteins↗

PubMed1994

Concordance of endotoxemia with gram-negative bacteremia in patients with gram-negative sepsis: a meta-analysis.

The Limulus amebocyte lysate (LAL) assay is a sensitive method for detecting endotoxin. Using gram-negative (GN) bacteremia as the basis for comparison, concordance with endotoxemia in 45 studies could be expressed as an odds ratio. Calculation of summary odds ratios by the Mantel-Haenszel-Peto method indicated that the concordance of the results was no higher by the chromogenic LAL assay than by the gelation version, and the sensitivity was improved by only 11% (62 versus 51%). Endotoxemia was detected in 77 (68%) of 114 patients with bacteremia caused by an organism that was not a member of the family Enterobacteriaceae, whereas endotoxemia was detected in only 120 (45%) of 269 patients with bacteremia caused by a member of the family Enterobacteriaceae or an anaerobe (P < 0.001). This difference was also apparent for patients with GN bacteremia for whom a fatal outcome had been recorded. The prevalence of GN bacteremia in the tested population and the type of etiological agent are critical and previously unrecognized variables which affect the interpretation of the LAL test in patients with suspected sepsis.

Bacteremia↗

PubMed1989

Aztreonam in the treatment of gram-negative meningitis and other gram-negative infections.

Ninety patients (41 males, 49 females) with a diagnosis of meningitis, urinary tract infection (UTI), gastroenteritis or other miscellaneous gram-negative infections were enrolled. Their ages ranged from 7 days to 10 years, with a mean age of 4 months. 58 (63%) patients had an etiology confirmed by either positive culture (52; 89%) or latex agglutination (6; 10%). 41 of these patients had meningitis diagnosed by positive CSE culture (38) or by positive CSF latex agglutination (3); 27/41 patients also had positive blood cultures. Aztreonam MIC100 for 27 isolates of Haemophilus influenzae, all ampicillin-sensitive, was 0.19 micrograms/ml; 4 Salmonella sp., 1 Neisseria meningitidis and 1 Serratia marcescens isolates were inhibited by 0.19 micrograms/ml, and the MIC100 for 2 Klebsiella pneumoniae, 1 Proteus vulgaris and 2 Pseudomonas aeruginosa isolates were 0.045 and 0.19, 0.022 and 12.5 micrograms/ml, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Aztreonam↗

PubMed2002

Early contingent negative variation (CNV) shows a small symmetrical negativity in a somatosensory paradigm.

The influence of sensory modulation on the early stage of information processing was investigated with a somatosensory contingent negative variation (CNV) paradigm. Whether or not even a somatosensory input as well as auditory or visual stimulus to one hemisphere elicits the symmetrical "early CNV" was also examined. Eleven normal individuals (3 males, 8 females) performed a conventional CNV paradigm with a click sound as the warning stimulus (WS) and a red light flash as the imperative stimulus (IS). Nine individuals (5 males, 4 females) did the somatosensory CNV paradigm with paired electrical stimuli as WS and IS. The subjects were instructed to press a button in response to IS as fast as possible. The early CNV amplitude was smaller and P300 latency was longer in somatosensory paradigm than conventional paradigm. In addition, the latency of P100 in a somatosensory paradigm was longer than that of N100 in a conventional paradigm. These findings suggest that the initiation of early detection, reflected by P100, the initiation of cognition, reflected by P300, and orienting response, reflected by early CNV, are delayed in a somatosensory CNV paradigm. Furthermore, all event-related potentials (ERPs) evoked by somatosensory stimuli showed a bilateral symmetry.

Adult↗

PubMed1992

[i(17q) appearing in acute phase in Ph1-negative, BCR-negative CML].

A 36-year-old woman was referred to our hospital because of splenomegaly in February 1989. The leukocyte count was 55,500/microliter without hiatus leukemicus. The leukocyte alkaline phosphatase score was low (29). The bone marrow showed myeloid hyperplasia (24.8% myeloblasts) but no dysplastic change. The karyotype of the bone marrow cells was 46, XX and a diagnosis of Ph1 (-) CML was made. Treatment with VCR, 6MP and prednisolone made 7-month duration chronic phase, but the abnormal karyotype.[46, XX, i(17q)] gradually increased to 100% of bone marrow cells. The patient died in June 1990. The evidence that not only a BCR rearrangement but also messages of BCR/ABL fusion gene were negative made us able to differentiate this case from Ph1(-), BCR(+) CML. The addition of an i(17q) results in partial monosomy of 17q (17q13;p53 gene) and partial trisomy of 17q (17q11.2-12;G-CSF gene). We examined the rearrangement of p53 gene and G-CSF-dependent tumor cell growth in vitro, demonstrating one allelic loss of p53 gene and independent cell growth on G-CSF respectively. It is thought that in Ph1 (-), BCR (-) CML as well as in Ph1 (+) CML, an i(17q) is related to the progression but not to the initiation of these leukemias. However the precise mechanism, including p53 gene inactivation by point mutation, is still to be elucidated.

Adult↗

PubMed1990

Chronic myelogenous leukemia with typical clinical and morphological features can be Philadelphia chromosome negative and "bcr negative".

The Philadelphia (Ph1) chromosome is found in the majority of patients affected by chronic myelogenous leukemia (CML), being considered the hallmark of the disease, but around 5-8% of patients diagnosed as CML lack the Ph1 chromosome-negative (Ph-) CML has been discussed extensively in the literature because of its heterogeneity. However, it is now accepted that some of the Ph1-CML patients have a disease indistinguishable from Ph1-positive (Ph+) CML. It was investigated whether Ph- CML with clinical and morphological features indicating true CML would always have bcr rearrangements, as the relocation of c-abl from 9q34 into the breakpoint cluster region on 22q11 is considered a crucial event in the pathogenesis of CML. From molecular studies, it seemed that Ph- CML with features of true CML always have the bcr rearrangement, while Ph- patients, lacking such rearrangement, have atypical forms of CML. Here we describe 8 Ph- CML and myeloproliferative syndrome (MPS) patients of whom 6 were by all respects true CML cases. Nevertheless, bcr rearrangement and expression of the classic bcr/abl chimeric mRNA was found in only 1 of the 6 patients. More advanced molecular techniques will be needed to understand which molecular mechanisms underlie Ph-, bcr- CML, resulting in phenotypes sometimes indistinguishable from Ph+, bcr+ CML.

Adult↗

PubMed1990

RAS mutations are rare events in Philadelphia chromosome-negative/bcr gene rearrangement-negative chronic myelogenous leukemia, but are prevalent in chronic myelomonocytic leukemia.

Previous reports have indicated that mutations of the RAS oncogenes are not associated with the chronic phase of Philadelphia chromosome-positive chronic myelogenous leukemia (Ph1+ CML). However, further studies were needed to determine their association with Ph1- CML and chronic myelomonocytic leukemia (CMML). Therefore, 6 patients with Ph1- CML who were also negative for BCR rearrangements (Ph1-/BCR- CML) and 30 patients with CMML were analyzed for the presence of RAS oncogene point mutations to determine the similarities of these diseases at the molecular level. The assay used the polymerase chain reaction for amplification of the target RAS sequences and panels of specific synthetic oligonucleotide probes for hybridization to wild type and/or mutated sequences. None of the six Ph1-/BCR- CML patients had mutations in the RAS oncogenes, while 17 of 30 (57%) of the CMML patients had RAS oncogene mutations. Eighty percent of the mutations involved substitution of aspartic acid for glycine (G----A) in the 12th or 13th codons of N-ras or K-ras. Furthermore, although not statistically significant, survival studies raise the possibility of shortened survival in patients with RAS oncogene point mutations, with the average survival being 33 months for Ph1-/BCR- CML, 35 months for CMML without point mutations, and 11 months for CMML with RAS mutations. Thus, RAS mutations appear to be associated with CMML and not Ph1-/BCR- chronic phase CML, there is a high propensity for the K-ras or N-ras mutations to involve an G----A substitution in the 12th or 13th codons, and RAS mutations in CMML may relate to prognosis and require further studies.

Gene Rearrangement↗

PubMed1996

[Cytolysins and homologous proteins produced by gram-negative bacteria. II. Hemolysins of Aeromonas, Serratia, Proteus and Morganella and proteins from gram-negative bacteria related to cytolysins].

This article presents the genetic determination, synthesis and activation of hemolysins produced by mentioned above bacteria, as well as the possible role of these toxins in the pathogenicity. All these cytolysins are related to RTX proteins presented to the previous paper. The short information about cytotoxic proteins from other Gram-negative bacteria (P. aeruginosa, K. pneumoniae, Vibrionaceae, G. vaginalis) and homologous proteins from E. chrysanthemi and R. leguminosarum biovar viciae are also included.

Aeromonas↗