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PubMed2000

Identification of alternative splicing and negative splicing activity of a nonsegmented negative-strand RNA virus, Borna disease virus.

Borna disease virus (BDV) is a nonsegmented negative-strand RNA virus that belongs to the Mononegavirales. Unlike other animal viruses of this order, BDV replicates and transcribes in the nucleus of infected cells. Previous studies have shown that BDV uses RNA splicing machinery for its mRNA expression. In the present study, we identified spliced RNAs that use an alternative 3' splice site, SA3, in BDV-infected cell lines as well as infected animal brain cells. Transient transfection analysis of cDNA clones of BDV RNA revealed that although SA3 is a favorable splice site in mammalian cells, utilization of SA3 is negatively regulated in infected cells. This negative splicing activity of the SA3 site is regulated by a putative cis-acting region, the exon splicing suppressor (ESS), within the polymerase exon of BDV. The BDV ESS contains similar motifs to other known ESSs present in viral and cellular genes. Furthermore, our results indicated that a functional polyadenylation signal just upstream of the BDV ESS is also involved in the regulation of alternative splicing of BDV. These observations represent the first documentation of complex RNA splicing in animal RNA viruses and also provide new insight into the mechanism of regulation of alternative splicing in animal viruses.

Alternative Splicing↗
PubMed2002

Chromosomal and comparative genomic analyses of HHV-8-negative primary effusion lymphoma in five HIV-negative Japanese patients.

A rare subset of HIV lymphoma, known as primary effusion lymphoma (PEL), is a high-grade tumour carrying human herpes virus 8 (HHV-8). Very little is known about genomic aberration in PEL, and only a few HIV-negative PEL have been reported. Here we report the results of chromosomal analysis and comparative genomic hybridisation (CGH) conducted to detect regions of gain and loss, in five HIV-negative Japanese cases of HHV-8-negative PEL. All patients except one (35-year-old female) were elderly men and the morphologic examination showed large cell type. PEL expressed B-cell-associated and activation-associated antigens, and exhibited clonal immunoglobulin genes. No HHV-8 was detected in all four examined cases, but Epstein-Barr virus (EBV) was detected in one case. Genomic abnormalities and aberrations were identified in all HHV-8/HIV-negative PEL. CGH studies showed gain in 19 of 24 chromosomes. Gains of 3q13-27, 8q24, 10q21-23 and Yq were detected in two of the five cases, but other gains were noted in each case. Chromosomal analysis revealed complex abnormalities both in numbers and structures. Burkitt lymphoma-associated t(8;22) was detected in one case, but +8 chromosome and c-myc amplification were detected in the other three cases by Southern blot and/or fluorecence in situ hybridization (FISH). Abnormality of chromosome 8, which associates with c-myc, was detected in four of the five HHV-8/HIV-negative PEL. However, the other common genomic abnormalities of HHV-8/HIV-negative PEL were not detected in our study, but the complex abnormalities seemed to be true rather than the usual large B-cell lymphoma. Our results suggest that multi-step genomic abnormalities might be associated in HHV-8/HIV-negative PEL tumorigenesis.

Adult↗
PubMed1998

Proof of hepatitis A virus negative-sense RNA by RNA/DNA-hybrid detection: a method for specific detection of both viral negative- and positive-strand RNA species.

The detection of hepatitis A virus (HAV) negative-strand RNA, which is synthesized during replication of the positive-strand RNA genome, proved to be difficult. We developed a method for the specific detection of HAV negative-strand RNA by RNA-DNA hybridization and luminescence detection using an anti-RNA:DNA hybrid antibody. This method, which is also applicable for the specific detection of positive-strand RNA, offers a simple, yet relatively rapid and certain means of detecting low amounts of RNA such as HAV negative-strand RNA. By using appropriate hybridization DNA probes, the method should be applicable for the detection of single-stranded RNA species of different viruses in general.

Animals↗
PubMed2001

Better negative than positive? Evidence of a bias for negative information about possible health dangers.

Do the results of a scientific study influence confidence in the study's validity and the magnitude of change in the resulting perceived danger of the health risk investigated? Findings from the three investigations reported here indicate that scientific results that confirm a danger (negative results) do affect confidence in a study's validity and resulting risk assessments differently than results indicating low risk (positive results). Findings of Study 1 revealed that research results indicating a health risk were more trusted than results indicating little health risk. This effect was independent of the credibility of the information source. Study 2 demonstrated that confidence in research results increased with an increasing indication of health risk. Study 3 showed that people have more confidence in the results of animal tests on a food additive indicating negative human health effects than in animal tests indicating that a food additive is harmless. The findings have important practical implications. The observed asymmetry between positive and negative research results may be one reason that people are afraid of many of the hazards they are faced with in modern society.

Adolescent↗
PubMed2001

Effect of positive and negative emotion on stimulus-preceding negativity prior to feedback stimuli.

Stimulus-preceding negativity (SPN) was recorded to investigate the effect of positive and negative emotion on the SPN preceding feedback stimuli. In the time-estimation task in which an acoustic stimulus was presented 3 s after a voluntary movement, (1) the negative valence (aversive band noise and pure tone) and (2) the positive valence (reward and no-reward) of feedback stimuli were manipulated. During noise conditions, participants received the band noise as a feedback stimulus except when their time estimations were accurate. They received a monetary reward for accurate time estimations under the reward conditions. The prefeedback SPN was larger under reward than no-reward conditions. In addition, the prefeedback SPN in the noise condition was larger compared with the pure tone condition. Our results appear to suggest that emotional anticipation is important in eliciting the prefeedback SPN.

Acoustic Stimulation↗
PubMed1993

Effects of a negative life event and negative perceived problem-solving alternatives on depression in adolescents: a prospective study.

The associations among negative life events (NLEs), perceived problem-solving alternatives (PPSA), and depression in adolescents were studied prospectively. One hundred and fifty high school students completed PPSA and depression scales when the term began, and the depression scale again after receiving term grades. Grade Change groups were defined by whether grades Increased or Dropped. The Dropped group who also selected Negative PPSAs increased in depression. No other group differences were found. Thus, experiencing a NLE is likely to lead to an increase in depressive symptomatology only for adolescents with primarily negative PPSAs, perhaps in interaction with prior depression, at least for the specific NLE studied here.

Achievement↗
PubMed1980

Evaluation of the four-hour Micro-ID technique for direct identification of oxidase-negative, Gram-negative rods from blood cultures.

A 4-h Micro-ID technique for direct identification of oxidase-negative gram-negative rods from positive blood cultures was compared to subculture and species identification of single colonies by API 20E and Micro-ID, using standardized inocula. A total of 127 patients (220 positive cultures) were studied. Isolates included 96 Escherichia coli, 46 Klebsiella pneumoniae, 7 Klebsiella oxytoca, 8 Enterobacter aerogenes, 17 Enterobacter cloacae, 19 Serratia marcescens, 2 Serratia liquefaciens, 8 Proteus mirabilis, 1 Salmonella species, 1 Morganella morganii, 6 Haemophilus influenzae, 2 Haemophilus parainfluenzae, 3 Bacteroides fragilis, 3 Acinetobacter calcoaceticus biotype anitratus, and 1 Pseudomonas maltophilia. In 90% of the cultures, identification by Micro-ID was identical to that obtained after subculture; if the 15 non-enterobacterial isolates were excluded, the corresponding figure was 96.6%. Enterobacteria identified incorrectly by direct Micro-ID were three S. marcescens (two identified as S. liquefaciens, one as Hafnia alvei), two S. liquefaciens (both identified as E. cloacae), and two K. pneumoniae (one identified as Klebsiella ozaenae, the other as Serratia rubidaea). None of the 15 non-enterobacterial cultures were correctly identified by Micro-ID (non-identifiable, or classified as Providencia/Yersinia/Klebsiella species). Although biochemical discrepancies between direct and final Micro-ID tests occurred in 41% of the enterobacterial cultures, this did not seriously interfere with identification. Direct species identification of Enterobacteriaceae from blood cultures by direct Micro-ID is accurate and easily performed and identified organisms within 4 h compared to at least 24 h by most other methods; the direct Micro-ID technique would be rendered even more valuable by the additional capability of identifying non-enterobacterial gram-negative isolates.

Acinetobacter↗
PubMed2002

Ability of the MicroScan rapid gram-negative ID type 3 panel to identify nonenteric glucose-fermenting and nonfermenting gram-negative bacilli.

The MicroScan Rapid Neg ID3 panel is designed for the identification of Enterobacteriaceae and nonenteric glucose-fermenting and nonfermenting gram-negative bacilli. We evaluated this panel for its ability to identify gram-negative non-Enterobacteriaceae bacteria. A total of 134 strains, representing 26 genera and 42 species, were taken from storage at -70(o)C, passaged three times before testing, and inoculated into the panels according to the manufacturer's directions before being inserted into a Walk/Away 96 instrument loaded with version 22.28 software. At the end of the initial 2.5-h incubation period, 89 isolates (66.4%) were correctly identified at a probability level of > or =85%. After additional testing recommended by the manufacturer was completed, another 11 isolates (8.2%) were correctly identified at probability levels of > or =85%. Twenty-five (18.7%) isolates were correctly identified after additional testing, but the probability levels were less than 85%. Two isolates were unidentified, and seven (5.2%) were incorrectly identified. The seven misidentified strains were not concentrated in any one genus. With an accuracy approaching 75%, this product may be used for the identification of the commonly isolated non-Enterobacteriaceae bacteria but may present problems in identification of other non-glucose-fermenting gram-negative bacilli.

Diagnostic Techniques and Procedures↗
PubMedDate not supplied

A survey for the rare blood group antigen variants, En(a-), Gerbich negative and Duffy negative on Espiritu Santo, Vanuatu in the South Pacific.

The people of Vanuatu exhibit several different genetic red cell polymorphisms. Some of these, such as alpha thalassaemia, are thought to have reached a high frequency as a result of selection pressure by malaria. In this study three rare blood group antigen variants, En(a-), Gerbich negative and Duffy negative, which are thought to confer a protective effect against malaria were sought in a sample of 214 (187 in the case of Duffy) from Espiritu Santo, Vanuatu. No individuals bearing these rare variants were found. The original settlers in Vanuatu are thought to have migrated from Papua New Guinea some 5,000 years ago, so it is of interest to note that no individuals were found to be Gerbich negative despite a high frequency in Melanesians living on some coastal parts of Papua New Guinea.

Antigenic Variation↗
PubMed1994

The stress-negative affect model of adolescent alcohol use: disaggregating negative affect.

The current study addressed three primary limitations of previous research on the relations among stress, negative affect and adolescent alcohol use. These include failure to distinguish among different types of negative affect, inattention to potential moderators of the relation between affect and alcohol use (e.g., impulsivity), and insufficient utilization of high-risk samples (e.g., children of alcoholics). In the current study, anger, anxiety and depression were found to differentially mediate the relation between stress and alcohol use, such that depression was the only significant mediator (above and beyond the effects of the other two affect measures). Impulsivity was also found to moderate the depression to alcohol use relation such that depressed, impulsive adolescents drank more heavily than depressed, nonimpulsive adolescents or nondepressed adolescents. Research implications include a need for future attention to the unique relations between forms of negative affect and alcohol use and to variables that might moderate these relations.

Adolescent↗
PubMed2005

Novel stimuli are negative stimuli: evidence that negative affect is reduced in the mere exposure effect.

Repeated exposure of a nonreinforced stimulus results in an increased preference for that stimulus, the mere exposure effect. The present study repeatedly presented positive, negative, and neutrally affective faces to 48 participants while they made judgments about the emotional expression. Participants then rated the likeability of novel neutrally expressive faces and some of these previously presented faces, this time in their neutral expression. Faces originally presented as happy were rated as the most likeable, followed by faces originally presented as neutral. Negative and novel faces were not rated significantly differently from each other. These findings support the notion that the increase in preference towards repeatedly presented stimuli is the result of the reduction in negative affect, consistent with the modified two-factor uncertainty-reduction model and classical conditioning model of the mere exposure effect.

Adult↗
PubMed2001

Differential responding to positive and negative items: the case of a negative item in a questionnaire for course and faculty evaluation.

Previous factor-analytic studies of self-rating scales have yielded a factor on which negatively worded items loaded separately. The present study investigated the existence for such a factor in a questionnaire for course and teacher evaluation which included one negative item. The questionnaire was administered in 1,095 university classes. Two factors emerged, an exclusively positive-item factor and another factor on which the single negative item and one positive item loaded. It was suggested that both items of Factor 2 were ambiguous and may identify tendencies such as acquiescence, random responding, and response sets.

Adult↗
PubMed1996

Contingent negative variation (CNV) and determinants of the post-imperative negative variation (PINV) in schizophrenic patients and healthy controls.

A slowly rising cortical potential shift with negative polarity following the imperative stimulus of a forewarned reaction time task, the 'post-imperative negative variation' (PINV), is regularly observed in schizophrenic patients but not in controls. The topography of the PINV suggests that it may originate in frontal cortical regions. We used a task designed to test two putative prefrontal cortical functions: working memory and processing of ambiguity. Nineteen patients with a chronic schizophrenic disorder and 19 control subjects matched for age, sex, and education participated in two experimental sessions. The EEG was recorded from frontal, central, temporal, and parietal leads over both hemispheres using a DC amplifier. PINV amplitudes were generally larger in patients than in controls. If the result of comparing physical features of the two successively presented stimuli (warning and imperative stimulus) was ambiguous rather than clear, an augmentation of the PINV amplitudes was seen in both groups. If this comparison required high rather than low involvement of working memory functions, PINV amplitudes were augmented in schizophrenic patients only. Scalp distribution of the PINV indicated a left-hemisphere fronto-central PINV maximum in patients, and a right-hemisphere predominance in controls, which was larger following ambiguous stimulus comparisons. These results suggest that ambiguity during the comparison of physical features of successively presented stimuli may be a general factor of the PINV in schizophrenic patients and healthy controls. Augmented involvement of working memory functions, presumably subserved by the prefrontal cortex, specifically affected the fronto-centrally predominant PINV in schizophrenic patients. This result is compatible with the hypothesis of prefrontal cortical dysfunctions in schizophrenia.

Adult↗
PubMedDate not supplied

[Preventive antibiotic administration for prevention of nosocomial septicemia in very small premature infants (VLBW infants)--preventive vancomycin administration against infections with coagulase negative streptococci--prevention of translocation with oral cefixime therapy in intestinal colonization with pathogenic gram-negative pathogens].

VLBW-infants below 1500 g of birth weight have a quite high risk to acquire a nosocomial sepsis. 20-40% of all infants exhibit signs of nosocomial infection once during neonatal intensive care. The rate of infection is related to technique and amount of used invasive devices as to gestational age. Coagulase-negative staphylococci (CONS) and gram-negative organisms contribute most to these cases of sepsis. In a three phase study we tried to demonstrate the efficacy of different mechanisms to change the rate of nosocomial sepsis. During the first phase a strict hygienical protocol was enforced as isolation, care with sterile gloves and aseptic techniques in introducing and maintaining i.v. lines. In a second phase we started a randomized controlled study of prophylactic vancomycin (10 mg/kg/day in two doses). In a third phase we added an oral antibiotic regime with cefixime for all patients with positive cultures for gramnegative organisms under the hypothesis of translocation from the gut as the way of infection. During the first phase 23.7% of 76 patients enrolled acquired CONS-sepsis, 0.52% gramnegative sepsis. During the second phase (41 patients) 6 patients in the control group acquired CONS-sepsis, none in the vancomycin-group. The rate of gramnegative infections was not different (4 and 3 cases). During the third phase (vancomycin plus cefixime eventually in cases of positive stool cultures) no case of nosocomial sepsis occurred (35 patients, 11 positive cultures). The management used in phase 3 reduced the rate of nosocomial infections in VLBW-infants drastically.

Anti-Infective Agents↗
PubMed1985

Incidence of Acinetobacter spp. and other gram-negative, oxidase-negative bacteria in fresh and spoiled ground beef.

A total of 1,409 gram-negative bacterial colonies were randomly selected from 19 samples of fresh and spoiled ground beef plated on six media. Only 137 (9.7%) were oxidase negative, and 20 (14.6%) of these were Acinetobacter spp., all of which were recovered from fresh meat samples. The importance of this group in both fresh and spoiled beef is less than is generally believed.

Acinetobacter↗
PubMed1988

Skin infection provoked by coagulase-negative Staphylococcus resembling gram-negative folliculitis.

A superficial pustular eruption with acute onset has been reported in patients with acne vulgaris receiving systemic antibiotic treatment. In all past cases the causative micro-organism was found to be a gram-negative bacterium. This case report describes a similar clinical picture under the same circumstances, in which the bacterium incriminated was a coagulase-negative Staphylococcus.

Acne Vulgaris↗
PubMed2002

CD5-negative, CD10-negative small B-cell leukemia: variant of chronic lymphocytic leukemia or a distinct entity?

CD5- and CD10-negative chronic lymphocytic leukemias are quite uncommon as compared to the CD5-positive CLL. We reviewed 250 sequential cases of peripheral blood lymphocytosis to characterize cases of small B-cell lymphoproliferative disorders, submitted with a clinical diagnosis of chronic lymphocytic leukemia exhibiting a non-classic immunophenotypic profile. Six cases of CD5-, CD10-negative chronic lymphocytic leukemias and no tissue involvement were identified that revealed high-density surface-membrane immunoglobulin and CD20 expression, with variable expression of CD11c, CD23, and CD25. Most had a profound leukocytosis (mean WBC 180 x 10(9)/L) with proliferation of mature-appearing lymphocytes. Subsequent bone marrow biopsies showed diffuse infiltration by neoplastic cells in all evaluated patients. The clinical course appeared indolent, with follow-up revealing three patients alive (survival time 38-68 months), while two died of unrelated causes and one was lost to follow-up soon after diagnosis. These cases may represent somewhat unusual chronic lymphoproliferative disorders, with morphologic features and immunophenotypic profile not readily classifiable, but which are certainly atypical for classic chronic lymphocytic leukemia. Some of these features are reminiscent of those seen in marginal-zone lymphoma. However, it is most unusual for this known to be tissue-based disease to present primarily as leukemia rather than lymphoma.

Antigens, CD↗