Inattentional deafness to auditory alarms: Inter-individual differences, electrophysiological signature and single trial classification.

Inattentional deafness can have deleterious consequences in complex real-life situations (e.g. healthcare, aviation) leading to miss critical auditory signals. Such failure of auditory attention is thought to rely on top-down biasing mechanisms at the central executive level. A complementary approach to account for this phenomenon is to consider the existence of visual dominance over hearing that could be implemented via direct visual-to-auditory pathways. To investigate this phenomenon, thirteen aircraft pilots, equipped with a 32-channel EEG system, faced a low and high workload scenarii along with an auditory oddball task in a motion flight simulator. Prior to the flying task, the pilots were screened to assess their working memory span and visual dominance susceptibility. The behavioral results disclosed that the volunteers missed 57.7% of the auditory alarms in the difficult condition. Among all evaluated capabilities, only the visual dominance index was predictive of the miss rate in the difficult scenario. These findings provide behavioral evidences that other early cross-modal competitive process than top down modulation process could account for inattentional deafness. The electrophysiological analyses showed that the miss over the hit alarms led to a significant amplitude reduction of early perceptual (N100) and late attentional (P3a and P3b) event-related potentials components. Eventually, we implemented an EEG-based processing pipeline to perform single-trial classification of inattentional deafness. The results indicate that this processing chain could be used in an ecological setting as it led to 72.2% mean accuracy to discriminate missed from hit auditory alarms.

Efficient mental workload estimation using task-independent EEG features.

OBJECTIVE: Mental workload is frequently estimated by EEG-based mental state monitoring systems. Usually, these systems use spectral markers and event-related potentials (ERPs). To our knowledge, no study has directly compared their performance for mental workload assessment, nor evaluated the stability in time of these markers and of the performance of the associated mental workload estimators.  This study proposes a comparison of two processing chains, one based on the power in five frequency bands, and one based on ERPs, both including a spatial filtering step (respectively CSP and CCA), an FLDA classification and a 10-fold cross-validation. APPROACH: To get closer to a real life implementation, spectral markers were extracted from a short window (i.e. towards reactive systems) that did not include any motor activity and the analyzed ERPs were elicited by a task-independent probe that required a reflex-like answer (i.e. close to the ones required by dead man's vigilance devices). The data were acquired from 20 participants who performed a Sternberg memory task for 90 min (i.e. 2/6 digits to memorize) inside which a simple detection task was inserted. The results were compared both when the testing was performed at the beginning and end of the session. MAIN RESULTS: Both chains performed significantly better than random; however the one based on the spectral markers had a low performance (60%) and was not stable in time. Conversely, the ERP-based chain gave very high results (91%) and was stable in time. SIGNIFICANCE: This study demonstrates that an efficient and stable in time workload estimation can be achieved using task-independent spatially filtered ERPs elicited in a minimally intrusive manner.

Dibutyl phthalate, the bioactive compound produced by Streptomyces albidoflavus 321.2.

It was found that the bioactive compound, dibutyl phthalate, was produced by a new soil isolate Streptomyces albidoflavus 321.2. Once this active compound was recovered by ethyl acetate from the fermented broth, being possible to isolate 13.4 mg/l, it was purified by paper, silica gel column, thin layer and gas chromatography. Structure was determined by analysing UV, IR and GC-MS spectra. During analysis, such active compound showed strong activity against gram-positive and gram-negative bacteria, as well as unicellular and filamentous fungi. The antimicrobial activity of the compound was reversed by the amino acid proline. No acute toxicity was observed.

Who's got what? A benchmarking exercise for tertiary neonatal units.

OBJECTIVES: To determine the current facilities available in level-3 neonatal units (NNU) in Australia and New Zealand to assist with establishment of standards for new NNU design. BACKGROUND: Many current NNU in Australia and New Zealand are planning new or redesigning existing facilities. There are no adequate local standards for NNU design available which reflect changing neonatal practices. METHODS: All level-3 neonatal units belonging to the Australia and New Zealand Neonatal Network (ANZNN) were invited to respond to a survey on NNU facilities. Questions were based around obtaining information on whether the NNU were planning to build or redesign the space and clinical facilities available in their existing facilities and what support and family spaces were provided. RESULTS: Twenty-six (six in New Zealand and 20 in Australia) of the 29 tertiary NNU in the ANZNN responded the survey. The oldest facility was built in 1960, with the most recent NNU being commissioned in 2003. Of the 26 responders, 18 indicated that they were planning to rebuild or renovate, with 13 anticipating completion within 6 years. The median floor area for existing level-3 cots was 11.1 m(2) (range 5.5-18.0 m(2)) and 5.8 m(2) (range 2.3-15.6 m(2)) for level-2 cots, respectively. Most units responded that storage space was insufficient (median 1.5 m(2) per cot, range 0.4-3.3 m(2) per cot). Most units had facilities for parents including a family lounge and parent overnight rooms, although 16 units indicated that they needed more overnight rooming in facilities. Noise levels in level-3 areas were described as being 'generally' or 'mostly noisy' in 14 of 25 responses, but noise levels in level-2 areas were less in the majority of responses. Privacy was cited as an issue for 80% of responding NNU with comments directed at either the layout or space constraints interfering with confidentiality or interactions with families. CONCLUSIONS: The majority of NNU have inadequate space and environmental control. The lack of space particularly impacts on infection control aspects, parental privacy and participation and staff satisfaction. Level-2 areas, where parent participation in the care of infants is often greater, should receive as much attention as higher technology level-3 areas. Furthermore, work should be undertaken to develop appropriate local recommendations for NNU design which are acknowledged by local government agencies and professional bodies and take into account the changes in neonatal care practices, integration of family in the care of infants and the needs of the staff.

Status of maternal and new born care at first referral units in the state of West Bengal.

A study was conducted in 12 First Referral Units (FRUs), selected through multistage sampling, from 6 districts of West Bengal. Infrastructure facilities, record keeping, referral system and MCH indicators related to newborn care were documented. Data was collected by review of records, interview and observation using a pre-designed proforma. Inadequate infrastructure facilities (e.g. no sanctioned posts of specialists, no blood bank at rural hospitals declared as First Referral Units etc.); poor utilization of equipment like neonatal resuscitation sets, radiant warmer etc, lack of training of the service providers were evident. Records/registers were available but incomplete. Referral system was found to be almost nonexistent. Most of the deliveries (86.1%) were normal delivery. Deliveries (87.71%) and immediate neonatal resuscitation (94.9%) were done mostly by nursing personnel. Institution based maternal, perinatal and early neonatal mortality rates were found to be 5.6, 62.4 and 25.2 per 1000 live births respectively. Eclampsia (48.9%), hemorrhage (17.7%), puerperal sepsis (7.1%) were reported to be major causes of maternal mortality. Common causes of early neonatal mortality were birth asphyxia (54.3%), sepsis (14.6%) and prematurity/LBW (12.4%).

Utilisation pattern of blood in a teaching hospital of Kolkata.

An annual utilisation of blood transfusion services at several depts. of R.G. Kar Medical College and Hospital, Kolkata were assessed among a sample of 3122 patients selected by Systematic Random Sampling Technique from the register made available in the blood bank there. Record analysis revealed that overall 79.4% of supplied blood units were actually transfused, wastage of 21.6%. Wastage was maximum in the Department of Gynae & Obstetrics (33.11%) and Surgery (32.87%). Only single unit of blood was requisitioned and transfused for 5.44% & 30.90% of the patients respectively. Most common indications of blood transfusion were for surgical cases (37.92%), followed by anaemia (34.80%) and haemorrhage (26.92%). The use of blood and blood products merit attention, appraisal and instructional guiding accordingly.

Survey of antimicrobial streptomycetes from soils of West Bengal: characterization and identification of potent broad spectrum antibiotic producing Streptomyces albidoflavus 321.2.

Survey of 611 streptomycetes isolates from 330 soil samples from various parts of West Bengal were done for their antimicrobial activity against Gram positive, Gram negative bacteria, unicellular and filamentous fungi. The strain 321.2 showed inhibition against all the test organisms used and found as potent. The morphological, cultural, physiological and biochemical characters were studied, compared with known species and identified as Streptomyces albidoflavus. This strain produces an antibiotic.

Transcriptional induction of the conserved alternative sigma factor RpoS in Escherichia coli is dependent on BarA, a probable two-component regulator.

The stationary phase expression of many conserved, adaptive bacterial proteins is dependent on RpoS, a second vegetative sigma factor. The regulation of RpoS itself, however, is complex and not fully understood, particularly at the level of transcription. In this report, we show that the observed hydrogen peroxide sensitivity of a mutant defective in expression of barA, a bacterial virulence factor, can be explained by a reduction in catalase activity, an RpoS-controlled function. Levels of katE mRNA, encoding the major catalase of Escherichia coli, were much lower in the barA mutant, suggesting that BarA is required for the expression of this RpoS-regulated gene. Expression of another RpoS-regulated gene, osmY, was also found to be severely reduced in the barA mutant. Employing Western analyses with anti-RpoS antisera and Northern analyses using probes specific for rpoS, we found that BarA is required for the exponential phase induction of RpoS itself. Operon lacZ fusion expression studies and Northern analyses indicate that BarA itself is maximally expressed in early exponential phase cultures immediately preceding the transcriptional induction of RpoS. Results of primer extension studies indicate that exponential phase expression from the rpoSp1 promoter is reduced by more than 85% in a barA mutant but could be efficiently complemented by a plasmid-borne copy of barA in trans. These results suggest that regulatory signals that are operant in exponentially growing cultures play an important role in effecting stationary phase gene expression.

Effect of tamoxifen treatment on the endometrial expression of human insulin-like growth factors and their receptor mRNAs.

The effect of tamoxifen (Tam) treatment on the endometrial expression of IGF-I and II/IGF-IR and IIR mRNAs was assessed by measuring the levels of expression of these mRNAs in the endometrial samples of Tam-treated postmenopausal breast cancer patients by RT-PCR assays. The levels of these mRNAs were compared with those in normal endometrium and in Type I and Type II endometrial carcinomas (EC). The promoter-specific transcript profiles of IGF-I and II were also elucidated. The levels of IGF/IGF-R mRNAs in the endometrium from Tam-treated patients were found to be comparable with the high levels of these mRNAs observed in the proliferative and early secretory phase endometrium and in the samples of Type I EC. These results indicate that Tam acts as an estrogen agonist in inducing the endometrial expression of these genes. Tam stimulated transcription from the multiple promoters of IGF-I and II, with the exception of IGF-II P2 promoter, in which case the transcription across exon 4 appeared to be inhibited. The profiles of IGF-I and II transcripts of endometrium from Tam-treated patients were similar to Type I EC but differed considerably from those of Type II EC. These results suggest that the Tam-associated ECs are likely to be similar to type I EC and will therefore have a more favorable prognosis.

Loss of IGF-II imprinting in endometrial tumors: overexpression in carcinosarcoma.

The genomic imprinting of the maternal allele defines the monoallelic expression of the IGF-II gene in most human tissues. The loss of imprinting (LOI) leading to biallelic overexpression of IGF-II has been reported in several human malignancies, including uterine leiomyosarcoma. To ascertain if LOI occurs in endometrial malignancies, the allelic expression of the IGF-II gene was examined in samples of normal human endometrium (n=22) and endometrial tumors (n=12) by assessing the ApaI polymorphism in cDNA segments amplified by RT-PCR. The biallelic overexpression of IGF-II mRNA, involving activation of all four (P1-P4) promoters, was detected in one normal endometrium and in one endometrial carcinosarcoma. Low level biallelic expression of IGF-II was also detected in two samples of hormone-unresponsive/Type II endometrial carcinomas. The level of IGF-I mRNA in these four samples was low. The IGF-IR mRNA was overexpressed in all endometrial cancers including the carcinosarcoma sample, but not in normal endometrium. These data suggest that LOI associated with overexpression of IGF-II and concomitant overexpression of IGF-IR may play a role in the rare carcinosarcoma of the endometrium.

Development and evaluation of a monoclonal antibody based competitive enzyme-linked immunosorbent assay for the detection of rinderpest virus antibodies.

A competitive enzyme-linked immunosorbent assay has been standardised for the detection of antibodies to rinderpest virus in sera from cattle, sheep and goats. The test uses a neutralising monoclonal antibody (MAb) directed against the haemagglutinin protein of rinderpest virus. The test is specific for rinderpest, as it failed to detect antibodies to peste des petits ruminants virus in convalescent goat sera. A 45% inhibition of the binding of the MAb to the antigen was used as the cut-off point for deciding the rinderpest status of the test samples. The specificity and sensitivity of the test and the stability of the test reagents were determined and compared to the results obtained using a commercial kit with approximately 1,200 serum samples from cattle, sheep and goats in India. The current test compared very well with the commercial kit. The test is expected to be extremely useful for sero-monitoring and sero-surveillance of rinderpest in countries which are actively pursuing a rinderpest eradication programme.

Discordant expression of insulin-like growth factors and their receptor messenger ribonucleic acids in endometrial carcinomas relative to normal endometrium.

The inappropriate expressions of insulin-like growth factors (IGF-I and II) and IGF-I receptor (IGF-IR) are implicated in the malignant growth of many cancers. To determine changes, if any, in the levels of expression of IGFs and IGF receptor genes in neoplastic endometrium, relative to normal endometrium, the mRNA levels of IGF-I and II and of IGF-IR and IIR were measured in samples of endometrial carcinomas (EC) and normal endometrium, through all phases of the menstrual cycle, by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) assays. In normal endometrium, the mRNA levels of IGF-I were elevated in the proliferative and early secretory phases. The IGF-II mRNAs were relatively high in the proliferative phase, but unaltered through early and late secretory phases. Significantly elevated levels of IGF-II transcripts were observed during the menstrual phase, suggesting a possible role of IGF-II in endometrial regeneration. A positive correlation between the levels of IGF-I and IGF-IR mRNAs, apparent in the samples of normal endometrium, was not observed in endometrial carcinomas. The IGF-IR and IIR mRNA levels were elevated in endometrial carcinoma samples. On the other hand, the IGF-I and II mRNA levels were conspicuously low in many carcinoma samples, which were not associated with hyperplasia (type II EC), but relatively elevated in two other carcinoma samples, associated with adenomatous hyperplasia (type I EC). These results albeit with few samples suggest the possibility that the overexpressed receptor, IGF-IR, could be activated differently in two types of endometrial carcinomas, namely ligand-dependently in type I ECs and ligand-independently in type II ECs.

Control of temperature during newborn transport: an old problem with new difficulties.

OBJECTIVE: To explore any changes in temperature control during neonatal emergency inter-hospital transport between 1977 and 1996. METHODS: Records were reviewed of all infants undergoing emergency transfer by the statewide Victorian Newborn Emergency Transport Service (NETS). Per axillary temperatures were recorded prospectively on arrival of transport team and at conclusion of transfer for all infants. RESULTS: The rate of hypothermia (< 36.0 degrees C) when NETS reached the infant has decreased overall (22% in 1977-79 to 7% in 1995-96) and for all weight groups; although in 1995-96 hypothermia was present in 36% of infants less than 1000 g when NETS arrived. The rate of hypothermia (< 36.0 degrees C) at the end of the transfer has remained at 3% overall for many years. The rate of hyperthermia at both times has increased significantly overall (12% in 1977-79 to 24% in 1995-96 on NETS arrival, 4%-19%, respectively at end of transfer) and for all weight groups except infants less than 1000 g. The range of abnormal temperatures has not substantially changed over time. CONCLUSION: There has been significant improvement in avoidance of hypothermia and cold stress amongst infants requiring emergency neonatal transport from 1977 to 1996. However, in order to improve the number of infants transferred who achieve a temperature in the normal range the need to avoid hyperthermia is highlighted. Infants who require incubator care for optimal medical management require continual monitoring of temperature and review of environmental conditions to optimise the conditions both prior to and during transport.

Minimal haemolysis in blood co-infused with amino acid and dextrose solutions in vitro.

OBJECTIVE: To examine the haemolytic effects of amino acid and dextrose solutions on co-infused packed red blood cells. METHODOLOGY: An in vitro study of packed cells co-infused at various rates with dextrose 5%, 10%, 15% and intravenous amino acid solution (Vamin; Kabi-Pharmacia, Baxter Healthcare Pty Ltd) in dextrose 5%, 10% and 15%. The degree of haemolysis was measured as free oxyhaemoglobin by spectrophotometer. Co-infused 0.9% saline and water were used as 0% and 100% haemolysis controls. RESULTS: Only minimal haemolysis was observed with the solutions tested. The greatest observed amount of haemolysis was 0.14%. CONCLUSIONS: Co-infusion of packed red blood cells with dextrose and amino acid solutions at the concentrations and infusion rates commonly used in neonatal care, does not cause clinically important haemolysis.

Endometrial transcripts of human insulin-like growth factors arise by differential promoter usage.

By the application of RT-PCR, we have demonstrated that in the human endometrium mRNAs for insulin-like growth factors, IGF-I and II, and their receptors are expressed not only in the intact endometrium, but also in the freshly isolated stromal and epithelial cells. The expression of multiple transcript forms of the IGF-I and II at various phases of the menstrual cycle, occurs by differential use of all four IGF-I transcriptional start sites, and two of the four known promoter sites of the IGF-II gene. The complete spectrum of transcripts is displayed by the proliferative phase and the menstrual phase endometrium. During the secretory phase, the exon 1 upstream start site of the IGF-I gene and the P2 promoter of the IGF-II gene are not used. Irrespective of the phase of the menstrual cycle, the stromal cells always display the same transcriptional patterns of both growth factor genes as those of the intact endometrium. In contrast, the epithelial cells do not express IGF-I transcript originating from the exon 2 upstream initiation site. These results indicate that the expressions of the IGF-I and II genes in the intact endometrium and stromal and epithelial cells are modulated at the transcriptional level during the menstrual cycle by differential usage of promoters and start sites.

Gene expression of A- and B-type natriuretic peptides in response to acute ethanol ingestion.

Given that ethanol ingestion is associated with a disruption of water and electrolyte balance in addition to being a significant risk factor for cardiovascular disease, we have investigated the gene expression of ANP and BNP in response to acute doses of ethanol. Wistar rats were administered either a 5 g/kg dose of ethanol or an equivalent volume of water, and atrial and ventricular tissue samples were removed at 30, 60, and 120 min for analyses. Although no differences in ANP mRNA were observed between ethanol and water-treated rats during the time course, BNP mRNA levels in ethanol-treated rats were 43% of those present in water-treated animals in atrial tissue at 120 min. In ventricular tissue, BNP mRNA levels were reduced similarly to 38% of control. These results suggest a possible differential regulation of A- and B-type natriuretic peptides under the influence of ethanol ingestion.

Genomic sequence, structural organization and evolutionary conservation of the 13.2-kDa subunit of rat NADH:ubiquinone oxidoreductase.

The 13.2-kDa subunit of NADH:ubiquinone oxidoreductase has been shown to be an integral part of the bovine iron-sulfur (IP) part of the protein. This subunit has been shown to interact with at least two other protein subunits of the IP fragment. The amino acid (aa) sequence of this subunit, determined from an acid extract of rat heart was used to generate an oligodeoxyribonucleotide probe which allowed isolation of a cDNA coding for the rat homologue of 13.2-kDa IP. The cDNA was used as a probe of a rat genomic DNA library and two clones were isolated, one of which contained the entire coding region for 13.2-kDa IP. Southern analysis indicates that the IP13 sequence exists as a single copy gene. The sequence of the genomic clone contains one intron and promoter elements including a TATAAA region. The 5' flank region has several potential regulatory sites, most notably regions similar to the nuclear respiratory factor 1 (NRF-1) motif, found in other genes which code for mitochondrial proteins [Evans and Scarpulla, Genes Dev. 4 (1990) 1023-1034]. The core domain of the deduced rat aa sequence has a high degree of identity with the mouse and cow homologues of this protein. The high degree of conservation of this protein indicates that the protein is essential for the function of complex I.