MalR-mediated regulation of the Streptococcus pneumoniae malMP operon at promoter PM. Influence of a proximal divergent promoter region and competition between MalR and RNA polymerase proteins.

The Streptococcus pneumoniae mal regulon contains two operons, malXCD and malMP involved in the uptake and utilization of maltosaccharides. Both operons are transcribed from two divergent promoters, P(X) and P(M), and are negatively regulated by the MalR transcriptional repressor. Purified MalR protein binds to two DNA regions that encompasses both promoters, thus occupying its two operators, O(M) and O(X).

Study of the microbial aggregation in Mycobacterium using image analysis and electron microscopy.

Cellular aggregation, which occurs in both prokaryotes and eukaryotes, is controlled by the hydrophobicity as well as the electrokinetic potential of the cell surface and substratum. It is known that the Mycobacterium genus form aggregates, but the influence of sugar on the cellular aggregation has not been reported for this genus. The mutant strain Mycobacterium sp.

The internal jugular vein maintains its regional anatomy and patency after carotid endarterectomy: a prospective study.

Objective: To validate the authors' published surface landmarks for gaining percutaneous access to the internal jugular vein (IJV), and to determine whether these surface landmarks were altered after neck surgery.

Summary Background Data: Carotid puncture and pneumothorax continue to be the most frequent mechanical complications of percutaneous IJV venipuncture, particularly when the anterior or posterior approaches are used. The authors' modified technique of IJV venipuncture was associated with a 0.

Conjugal transfer of plasmid pMV158: uncoupling of the pMV158 origin of transfer from the mobilization gene mobM, and modulation of pMV158 transfer in Escherichia coli mediated by IncP plasmids.

The streptococcal plasmid pMV158 encodes a gene cassette involved in its mobilization by large conjugative plasmids. Two elements compose this region: i) the mobM gene, encoding the MobM protein that initiates transfer, and ii) the origin of transfer, oriT, which is the target of MobM. In vitro, MobM protein introduces a specific nick within the pMV158-oriT region on supercoiled pMV158 DNA.

High ALT levels predict viremia in anti-HCV-positive HD patients if a modified normal range of ALT is applied.

Aims: Some studies have reported that ALT determination is of little value in the study of chronic hepatitis C in hemodialysis (HD) patients. This could be due to the fact that ALT values are lower in HD patients than in healthy individuals; ALT in HCV infection follows a fluctuating pattern and the HCV viremia may be intermittent. The aim of this study was to establish the reference ALT values in a large group of hepatitis-free HD patients, and to determine their role in predicting viremia in anti-HCV-positive HD patients.

IDO induction in IFN-gamma activated astroglia: a role in improving cell viability during oxidative stress.

In the central nervous system (CNS), astrocytes play an integral role in the maintenance of neuronal viability and function. Inflammation within the CNS increases the concentration of oxidative metabolites and, therefore, the potential for NAD depletion through increased poly-(ADP-ribose) polymerase (PARP) activity. However, the activity of indoleamine 2,3-dioxygenase (IDO), the rate limiting enzyme for de novo NAD synthesis, is also markedly increased in astrocytes during inflammation.

Plasmid copy number control: an ever-growing story.

Bacterial plasmids maintain their number of copies by negative regulatory systems that adjust the rate of replication per plasmid copy in response to fluctuations in the copy number. Three general classes of regulatory mechanisms have been studied in depth, namely those that involve directly repeated sequences (iterons), those that use only antisense RNAs and those that use a mechanism involving an antisense RNA in combination with a protein. The first class of control mechanism will not be discussed here.

Superovulation in vesper mouse Calomys musculinus (Rodentia-Sigmodontinae).

Optimal conditions for pharmacological induction of ovulation of vesper mouse, Calomys musculinus, were analyzed. The best superovulation (a mean of about 21 eggs per female, range 12-45) was induced by the administration of 12 IU of PMSG followed 48 hr later by injection of 15 IU of hCG. Ovulation started about 10 hr after administration of hCG and was completed during the next 4-5 hr.

Quantitative detection of Streptococcus pneumoniae cells harbouring single or multiple copies of the gene encoding the green fluorescent protein.

A modified gfp gene from Aequorea victoria, encoding a variant of the green fluorescent protein (GFP), was subcloned into the mobilizable plasmid pMV158. gfp was placed under the control of the inducible P(M) promoter of the Streptococcus pneumoniae gene malM, cloned in plasmid pLS70. The P(M) promoter is regulated by the product of the pneumococcal malR gene, which is inactivated by growing the cells in maltose-containing media.

Occupational and environmental medicine in Colombia.

Colombia is a country rich in natural resources, with a steadily developing economy. Occupational and environmental medicine (OEM) education and practice have developed relatively recently in Colombia, mainly in response to a series of long overdue (and still partially implemented) reforms to the health care, social benefits, and education systems. Expansion in general and occupational health coverage of the Colombian population and development of OEM education and training were to be achieved through a clear stimulus to private sector initiatives.

Construction of a tightly regulated plasmid vector for Streptococcus pneumoniae: controlled expression of the green fluorescent protein.

We have constructed a regulated plasmid vector for Streptococcus pneumoniae, based on the streptococcal broad-host-range replicon pLS1. As a reporter gene, we subcloned the gfp gene from Aequorea victoria, encoding the green fluorescent protein. This gene was placed under the control of the inducible P(M) promoter of the S.

Neurophysiological studies of thin myelinated (A delta) and unmyelinated (C) fibers: application to peripheral neuropathies.

Dysfunction of small fibers may appear in isolation or associated with large fiber lesions. In some acute neuropathies, such as pandysautonomia, small-fiber impairment is relatively pure but it may also appear in disorders with prominent somatic damage, such as Guillain-Barré syndrome, in which autonomic failure worsens the prognosis. At the present time, chronic idiopathic distal small-fiber neuropathy is diagnosed more frequently, and in some prevalent disorders, such as diabetic or amyloidotic polyneuropathies, small-fiber dysfunction is very noticeable.

[Small fiber dysfunction in peripheral neuropathies].

Introduction: Disfunction of thin myelinated and unmyelinated fibers may appear isolated or in association with large-myelinated fibers lesion. Small-fiber neuropathy includes autonomic and sensory symptoms, most prominent of them thermo-algesic deficits.

Development And Conclusion: In some acute neuropathies, small-fiber lesion is relatively pure, as in pandysautonomia, but it also appears in disorders with prominent somatic involvement, such as the Guillain-Barre syndrome, in which case autonomic symptoms worsens the prognosis.

[Neurophysiological study of thin myelinated and unmyelinated fibers].

Introduction: Standard neurophysiological techniques evaluate thick myelinated fibers. Yet, peripheral nerves are equally composed of thin myelinated and unmyelinated fibers. The latter are responsible for autonomic function as well as temperature and pain perception.

Expression of green fluorescent protein in Lactococcus lactis.

The gfp gene from Aequorea victoria, encoding the green fluorescent protein (GFP) has been expressed in Lactococcus lactis subsp. lactis biovar cremoris MG1363, upon construction and introduction of plasmid pLS1GFP into this host. GFP was monitored in living cells during growth to evaluate its use in molecular and physiological studies.

Psychopathology, mother-child interaction, and infant development: substance-abusing mothers and their offspring.

The course of severe depressive symptoms from pregnancy to 6 months postpartum, as well as the occurrence of severe paranoid symptoms prenatally, were examined by the Millon Clinical Multiaxial Inventory I and the Beck Depression Inventory, in 78 women who were heavy, chronic cocaine users and who retained custody of their children after birth. Six months postpartum, the quality of caregiving was observed and assessed in the home, and the children were assessed on the Bayley MDI Index in the laboratory. Mothers who were depressed and paranoid prenatally, regardless of whether the depression continued to 6 months postpartum, were less sensitive in caregiving than women without severe symptoms of paranoia or depression during pregnancy or those who reported only depression that lifted by 6 months postpartum.

A functional lagging strand origin does not stabilize plasmid pMV158 inheritance in Escherichia coli.

Plasmid rolling circle replication generates single-stranded DNA intermediates. The intracellular amount of these molecules depends upon the efficiency of the conversion of single-stranded into double-stranded plasmid forms, that is, the functionality of the lagging strand origin (sso). The broad-host-range streptococcal plasmid pMV158 harbors two different ssos, both of which function efficiently in Streptococcus pneumoniae but poorly in Escherichia coli.

[Hypersomnia and thalamic and brain stem stroke: a study of seven patients].

Background And Aim: Thalamic and brainstem strokes are a cause of organic hypersomnia. In thalamic lesions it has been attributed to disruption of ascending activating impulses from the brainstem reticular formation and to insufficient spindling and slow-wave production, which depends upon activities of reticular thalamic nucleus and thalamocortical neurons, respectively. Reported sleep disorders in brainstem lesions have occasionally been contradictory and that is because of the presence of nearby structures in the brainstem with different functions in sleep-waking cycle.

Expression of the mobM gene of the streptococcal plasmid pMV158 in Lactococcus lactis subsp. lactis.

The streptococcal plasmid pMV158 is not auto-transferable, but it can be mobilised between bacteria by the use of functions supplied by plasmids of the pIP501/pAM beta 1 family. Plasmid pMV158 encodes a protein, MobM, which is involved in its mobilisation. This process initiates when MobM specifically cleaves supercoiled pMV158 plasmid DNA at the origin of transfer, oriT.

Characterization of a single-strand origin, ssoU, required for broad host range replication of rolling-circle plasmids.

Single-stranded DNA (ssDNA) promoters are the key components of the single-strand origins (ssos) of replication of rolling-circle (RC) replicating plasmids. The recognition of this origin by the host RNA polymerase and the synthesis of a short primer RNA are critical for initiation of lagging-strand synthesis. This step is thought to be a limiting factor for the establishment of RC plasmids in a broad range of bacteria, because most of the ssos described are fully active only in their natural hosts.

Continuity and change in the social competence of children with autism, Down syndrome, and developmental delays.

The aims of this longitudinal study were: (1) to assess the continuity and change in diagnosis, intelligence, and language skills in children with autism, Down syndrome, and other developmental delays, (2) to specify the deficits in social competence and language skills in these children, and (3) to identify precursors in the preschool period of gains in language skills and of peer engagement in the mid-school years. The initial sample consisted of 70 children with autism, 93 children with Down syndrome, 59 children with developmental delays, and 108 typically developing children, with the first three groups of children studied when they were between 2 and 6 years of age. At follow-up, 51 children with autism, 71 children with Down syndrome, and 33 children with developmental delays were assessed at mean ages around 10-13 years.

Mobilisation of the streptococcal plasmid pMV158: interactions of MobM protein with its cognate oriT DNA region.

The streptococcal plasmid pMV158 encodes the relaxase protein, MobM, involved in its mobilisation. Purified MobM protein specifically cleaved supercoiled or single-stranded DNA containing the plasmid origin of transfer, oriT. Gel retardation and DNase I footprinting assays performed with DNA fragments containing the plasmid oriT provided evidence for specific binding of MobM by oriT DNA.

Evaluation of algorithms for the registration of 99Tcm-HMPAO brain SPET studies.

Five functions of merit were used for the registration of 99Tcm-HMPAO brain SPET studies. The correlation coefficient (COR), the stochastic sign change (SSC), the standard deviation of ratios (SDR), the sum of the absolute differences (SAD) and a new function based on a local correlation coefficient (LOC) were tested in the registration of photic neuroactivation (ACT), epilepsy (EPL) and Wada (WAD) SPET studies. The comparison included simulated and real studies.