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PubMed2006

Anatomic demarcation by positional variation in fibroblast gene expression programs.

Fibroblasts are ubiquitous mesenchymal cells with many vital functions during development, tissue repair, and disease. Fibroblasts from different anatomic sites have distinct and characteristic gene expression patterns, but the principles that govern their molecular specialization are poorly understood. Spatial organization of cellular differentiation may be achieved by unique specification of each cell type; alternatively, organization may arise by cells interpreting their position along a coordinate system. Here we test these models by analyzing the genome-wide gene expression profiles of primary fibroblast populations from 43 unique anatomical sites spanning the human body. Large-scale differences in the gene expression programs were related to three anatomic divisions: anterior-posterior (rostral-caudal), proximal-distal, and dermal versus nondermal. A set of 337 genes that varied according to these positional divisions was able to group all 47 samples by their anatomic sites of origin. Genes involved in pattern formation, cell-cell signaling, and matrix remodeling were enriched among this minimal set of positional identifier genes. Many important features of the embryonic pattern of HOX gene expression were retained in fibroblasts and were confirmed both in vitro and in vivo. Together, these findings suggest that site-specific variations in fibroblast gene expression programs are not idiosyncratic but rather are systematically related to their positional identities relative to major anatomic axes.

Cell Differentiation↗
PubMed1997

Use of an inducible regulatory protein to identify members of a regulon: application to the regulon controlled by the leucine-responsive regulatory protein (Lrp) in Escherichia coli.

Procedures were developed to facilitate the identification of genes that belong to a given regulon and characterization of their responses to the regulator. The regulon controlled by the Escherichia coli leucine-responsive regulatory protein (Lrp) was studied by isolating random transcriptional fusions to lacZ, using lambda placMu53 and a strain in which lrp is under isopropylthio-beta-D-galactopyranoside (IPTG)-inducible control. Fusions exhibiting IPTG-responsive beta-galactosidase activity were cloned by integrating the suicide vector pIVET1 via homologous recombination at lacZ, followed by self-ligating digested chromosomal DNA. We verified the patterns of lacZ expression after using the plasmid clones to generate merodiploid strains with interrupted and uninterrupted copies of the same sequence. If the merodiploid expression pattern was unchanged from that shown by the original fusion strain, then the cloned fusion was responsible for the regulatory pattern of interest; a difference in the expression pattern could indicate that the original strain carried multiple fusions or that there were autogenous effects of having interrupted the fused gene. Using these procedures, we generated a fusion library of approximately 5 x 10(6) strains; approximately 3,000 of these strains were screened, yielding 84 Lrp-responsive fusions, and 10 of the 84 were phenotypically stable and were characterized. The responses of different fusions in a given operon to in vivo Lrp titrations revealed variations in expression with the position of insertion. Among the newly identified members of the regulon is an open reading frame (orf3) between rpiA and serA. Also, expression of a fusion just downstream of dinF was found to be Lrp dependent only in stationary phase.

Bacterial Proteins↗
PubMed2006

Geographical stability of enterococcal antibiotic resistance profiles in Europe and its implications for the identification of fecal sources.

This manuscript describes the use of a recently developed microbial source tracking (MST) technique to determine sources of fecal bacteria (enterococci) from four separate European countries. The investigation aimed to evaluate whether the origin of bacterial populations from France, Spain, and Sweden (n = 456) could be predicted using a library of antibiotic resistance patterns of enterococci of known origin assembled in the United Kingdom (n = 2739). Bacterial isolates were exposed to a battery of 31 antibiotic tests and classified into source groups using discriminant function analysis (DFA). Results showed that while on average 72% of the U.K. isolates could be correctly classified as originating from either municipal wastewater (MW), livestock, or wild birds, only 43% of non-U.K. isolates could be successfully classified into the same source categories. The results suggested that patterns of resistance amongst isolates contained in the U.K. library were not representative of those found in the other locations and that it may not be possible to share libraries over large distances, such as those in this study. Future MST studies using antibiotic resistance analysis (ARA) in Europe may therefore require the assembly of watershed specific libraries, increasing the cost of such studies.

Drug Resistance↗
PubMed1988

An immunohistochemical study of primary ovarian sarcoma. An evaluation of nine tumors.

Nine cases of primary ovarian sarcoma were studied with a panel of 10 antibodies by using the avidin-biotin-complex immunoperoxidase technique. Original diagnoses included five mixed müllerian tumors (MMT) homologous type, two MMT heterologous type, and two pure sarcomas (PS). Cytokeratin immunoreactivity was observed in epithelial components of all MMTs, but was not observed in PS. Two tumors originally classified as MMT also showed cytokeratin positivity in spindle-cell components. All the PSs and the spindle-cell components in six of seven MMTs showed positive staining for vimentin. Positive staining for desmin and myoglobin was found in one MMT in which cells with cytoplasmic cross-striations were identified on hematoxylin and eosin sections. However, less differentiated rhabdomyoblastic cells also stained for desmin and myoglobin, facilitating their recognition. Immunoreactivity for epithelial membrane antigen was noted in well-differentiated epithelial components of six MMT cases. One case stained with antibodies to carcinoembryonic antigen, four with S-100 protein, five with alpha-1-antitrypsin, and four with muramidase. No staining of stromal hyaline droplets was observed with any antibodies. Because of the immunohistochemical staining pattern, two of the original diagnoses were changed. Application of immunohistochemistry to spindle tumors of ovary is discussed.

Female↗
PubMed1994

Postictal behavior. A clinical and subdural electroencephalographic study.

OBJECTIVE: To examine postictal behaviors after temporal lobe complex partial seizures (CPSs) and to correlate these behavioral phenomena with side of origin and ictal spread pattern. DESIGN: Review language and other behavioral phenomena after seizures defined by subdural electroencephalography. SETTINGS: A surgical epilepsy center. PATIENTS: We studied postictal behavior following 65 CPSs in 18 patients with left hemisphere language dominance using subdural electrode recordings. INTERVENTION: Subdural electrodes. MAIN OUTCOME MEASURES: Language function, affect, orientation, and postictal automatisms. RESULTS: Following the CPS ictal discharge, the mean interval for initial nonreflexive response to an environmental stimulus was 43 seconds (left foci, 57 seconds; right foci, 29 seconds; not significantly) and for first correct verbal response was 219 seconds (left foci, 275 seconds; right foci, 167 seconds; not significant). Impaired comprehension with fluent but unintelligible speech, as well as anomia, occurred after seizures arising from either temporal lobe. All nine seizures followed by global or nonfluent aphasia originated on the left side. Paraphasic errors were significantly more common after left temporal CPSs. Prolonged disorientation for place and flat affect were significantly more common after right temporal CPS. Postictal automatisms were frequent and included rubbing of the face, fumbling and picking hand movements, and repetitive oral movements. CONCLUSIONS: Postictal paraphasias, disorientation for place, and flat affect most likely reflect the functions of the area from which seizures arise but not the areas involved by spread.

Adolescent↗
PubMed1986

Human papillomavirus types 16 and 18 sequences in early cervical neoplasia.

A total of 100 colposcopic biopsies from patients with abnormal Papanicolau's tests were surveyed for the presence of human papillomavirus (HPV) types 16 and 18 sequences by spot-blot hybridization. HPV 16 and 18 DNA sequences were detected in 58% of the biopsies. None of the cervical intraepithelial neoplasia grade I (CIN I) contained HPV 16 while 50% of the CIN III lesions (carcinoma in situ, CIS) contained HPV 16. HPV 18-related sequences were equally represented in CIN I, II, and III. Southern-blot hybridization of total undigested cellular DNA revealed the presence of HPV DNA sequences only in an episomal form. While the restriction enzyme patterns in HPV 16-positive samples were mostly identical to the originally cloned sequence, the restriction enzyme pattern for HPV 18-positive samples were different from that of HPV 18 but identical to each other. Furthermore, this DNA hybridized more strongly to HPV 18 under nonstringent conditions, suggesting a new type.

Colposcopy↗
PubMed1992

Origin of mutation in sporadic cases of haemophilia-B.

Of the 45 haemophilia-B patients registered at the haemophilia centre in Malmö, Sweden, 24 are the sole members of their families to be affected, and in 13 of these 24 cases, ascendant relatives are available for study. Detection of the gene defect showed the mutation to be de novo in the proband in 3 of these 13 cases, and inherited from a carrier mother in the remaining 10 cases. All 10 carrier mothers were shown to have de novo mutations, as the patients' grandfathers were phenotypically and/or haematologically normal, and the grandmothers were non-carriers. Seven restriction fragment length polymorphisms (RFLPs) of the factor IX gene were used to determine whether the de novo mutations of the 10 carrier mothers were of paternal or maternal origin. In 6/10 cases, the RFLP patterns were informative, and indicated the mutation to be of paternal origin.

Adolescent↗
PubMed1984

Ventricular tachycardia of left bundle branch block configuration in patients with isolated right ventricular dilatation. Clinical and electrophysiological features.

Electrophysiological studies showed ventricular tachycardia in five patients (four male, one female) with isolated right ventricular dilatation. All had been asymptomatic before the onset of palpitation which had developed in adolescence or early adult life. Tachycardia had been associated with syncope in four patients, and three had been resuscitated from ventricular fibrillation before investigation. The electrocardiogram during ventricular tachycardia showed a left bundle branch block pattern, and endocardial mapping at electrophysiological study confirmed the right ventricular origin. The presenting tachycardia could be induced in all patients by programmed stimulation, and in three patients ventricular tachycardia of differing configuration could be induced, but the right ventricular origin and left bundle branch block pattern were maintained. In two patients ventricular tachycardia degenerated into ventricular fibrillation. Cineangiography, cross sectional echocardiography, and multigated radionuclide angiography confirmed the dilated abnormal right ventricle while indicating that left ventricular function was normal. On resting electrocardiograms T wave inversion over the right precordial leads was the sole abnormality. There were no signs of right heart failure and exercise tolerance was normal. Four patients have received maintenance treatment with antiarrhythmic drugs, and one had undergone operative mapping and ablative surgery. Thus ventricular tachycardia complicating right ventricular dilatation may be associated with serious symptoms and ventricular electrical instability; and in adults it may be suspected on clinical grounds by inverted T waves in the right precordial leads.

Adult↗
PubMed1997

Genetics of the Chuetas (Majorcan Jews): a comparative study.

A study of the Chueta population has been carried out to establish the genetic relationships between the Chuetas and other Jewish and non-Jewish circum-Mediterranean populations and to identify which markers discriminate better between these populations. The analyses used were principal components analysis, factorial analysis of correspondences, and stepwise discriminant analysis. The results indicate that most of the Jewish communities resemble each other and other Middle Eastern populations, because of their common origin, but they also have affinities with their host peoples. The results also agree with those of most researchers in the importance of G6PD, FY, and MN as geographic markers and in the role of HP, GLO1, and Rh as indicators the Middle Eastern origin of the Jews but differ with respect to the geographic pattern of ABO. Moreover, the Jewish origin of the Chuetas remains evident in their genetic pool, although they resemble their neighboring populations more than other Jewish populations. Finally, HP, G6PD, ABO and Rh are the most important variables in determining the position of the Chuetas with respect to other Jewish and non-Jewish populations.

Discriminant Analysis↗
PubMed2006

A place for fiber diffraction in the detection of breast cancer?

AIMS: To review the potential relevance and the place that a particular change in the fiber diffraction of hair might have in the future management of breast cancer and other pathologies. METHOD: A comprehensive overview was obtained using a complete search of the Australian National University Library (data range) and Medline (data range) using the search terms "review breast cancer screening/diagnosis/detection" and "X-ray diffraction of hair". Publications in the past 5 years were selected but older reports that were commonly referenced were not excluded. RESULTS: To date, our results have demonstrated that a specific change occurs in the diffraction pattern of hair for persons with breast cancer. Further research has shown that this change is present in the hair at an earlier stage of the cancer growth than is detectable by mammography. In addition, the change has been found to disappear when the cancer has been successfully removed. DISCUSSION/CONCLUSION: This technology uses only a few hairs, is totally user-friendly, non-invasive and does not require the patient to be exposed to any radiation. As a low-risk procedure, it could potentially provide a much needed, cost-effective early screening test for the presence of breast cancer in women of any age. As the patients are not required to be present during the test, it could also provide a testing service for women in remote areas. In this review, the origin of the diffraction pattern and the diagnostic information that can be gleaned from it are outlined.

Breast Neoplasms↗
PubMed1982

Hydrocarbons in the Western Mediterranean Sea, 1981.

Hydrocarbons in the western Mediterranean Sea were analysed for surface microlayer and subsurface waters during April 1981. Three methods were used for determining both concentrations and markers distribution patterns: U.V. spectrofluorimetry, and original HPLC/U.V. spectrophotometry method and capillary gas liquid chromatography. No systematic relationship was found between concentrations determined by U.V. spectrofluorimetry and HPLC/U.V. spectrophotometry. Concentrations variation ranges are: 0.01-0.20 microgram 1(-1) for dissolved aromatic hydrocarbons; 0.02-0.13 microgram 1(-1) for particulate aromatic hydrocarbons; 0.02-20.57 micrograms 1(-1) for dissolved n-alkanes; 0.13-0.83 microgram 1(-1) for particulate n-alkanes. Surficial waters appear as very slightly polluted with an exception the Ligurian Sea for which highest concentrations were encountered. There is a slight enrichment of particulate hydrocarbons in the surface microlayer in the range 1-3. But, dissolved hydrocarbons can be either depleted or enriched up to 270 times in the surface microlayer, indicating the extreme efficiency of sea-air exchange processes. Aromatic fingerprints and n-alkane distribution patterns are discussed both for pollution and fractionation processes indicators at the sea-air interface.

Hydrocarbons↗
PubMed1996

Single-joint rapid arm movements in normal subjects and in patients with motor disorders.

In normal subjects the execution of single rapid one-joint movements is characterized by an electromyographic (EMG) pattern composed of three discrete bursts of activity; two bursts (first and second agonist bursts, or AG1 and AG2) are present in the agonist muscle separated by an almost complete period of electrical silence. During this pause, another burst (antagonist burst, or ANT) occurs in the antagonist muscle. If a rapid movement is executed during tonic activation of the agonist muscle, tonic activity is inhibited just prior to AG1 onset (agonist inhibition). Similarly, if the movement is performed during tonic activation of the antagonist muscle, such activity is also inhibited prior to AG1 onset (antagonist inhibition). Antagonist inhibition also starts prior to AG1 onset and lasts until ANT onset. A general descriptor of the kinematic features related to the EMG pattern described above is a symmetrical and unimodal velocity profile that is bell-shaped and shows an acceleration time roughly equal to the deceleration time. This holds true for movements performed under low accuracy constraints; as accuracy demands become stricter and stricter, the peak velocity decreases but, as long as the movement is made with one continuous trajectory, the velocity profile remains roughly symmetrical. In general terms, the function of AG1 is to provide the impulsive force to start the movement; the function of ANT is to halt the movement at the desired end-point; and the function of AG2 is to dampen out the oscillations which might occur at the end of the movement. The timing and size of the bursts vary according to the speed and amplitude of the movement. The origin of the EMG pattern is a central programme, but afferent inputs can modulate the voluntary activity. In this paper, we also review the EMG and kinematic abnormalities that are present during the execution of single-joint, rapid arm movements in patients with Parkinson's disease, Huntington's disease, Sydenham's chorea, dystonia, athetosis, cerebellar deficits, upper motor neuron syndrome, essential tremor and large-fibre sensory neuropathy. The data from these studies lead us to the following conclusions: (i) the basal ganglia have a role in scaling the size of AG1, reinforcing the voluntary command and inhibiting inappropriate EMG activity; (ii) the cerebellum has a role in timing the voluntary bursts and probably in implementing muscle force phasically; (iii) the corticospinal tract has a role in determining spatial and temporal recruitment of motor units; (iv) proprioceptive feedback is not necessary to produce the triphasic pattern but it contributes to the accuracy of both the trajectory and the end-point of rapid movements.

Arm↗
PubMed1990

Nerves and nerve plexuses of the human vertebral column.

The origin, distribution, and termination pattern of nerves supplying the vertebral column and its associated structures have been studied in the human fetus by means of an acetylcholinesterase whole-mount method. The vertebral column is surrounded by ventral and dorsal nerve plexuses which are interconnected. The ventral nerve plexus consists of the nerve plexus associated with the anterior longitudinal ligament. This longitudinally oriented nerve plexus has a bilateral supply from many small branches of the sympathetic trunk, rami communicantes, and perivascular nerve plexuses of segmental arteries. In the thoracic region, the ventral nerve plexus also is connected to the nerve plexuses of costovertebral joints. The dorsal nerve plexus is made up of the nerve plexus associated with the posterior longitudinal ligament. This nerve plexus is more irregular and receives contributions only from the sinu-vertebral nerves. The sinu-vertebral nerves originate from the rami communicantes and, in the cervical region, also from the nerve plexus of the vertebral artery. Thick and thin sinu-vertebral nerves are found. Most frequently three types of thick sinu-vertebral nerves are observed, i.e., ascending, descending, or dichotomizing ones. Finally, the distribution of the branches of the ventral and dorsal nerve plexuses and of the sinu-vertebral nerves is described.

Cervical Plexus↗
PubMedDate not supplied

The mental adjustment to cancer (MAC) scale: French replication and assessment of positive and negative adjustment dimensions.

The Mental Adjustment to Cancer (MAC) scale was validated on a heterogeneous French sample of 317 cancer patients. Internal consistency was satisfactory for the original subscales (alpha coefficients=0.62-0.80), except for the Fatalism subscale (alpha=0.40). The intercorrelations of the subscales and the correlations between the subscales and Anxiety and Depression criteria were congruent with the values reported in the literature. Multidimensional Scaling revealed three positive and three negative subsets of items revealing adjustment to cancer. Congeneric factor analysis of the subsets was performed with LISREL 8.3 and only three of them (after discarding certain items) were retained: Fighting Spirit (FS) Hopelessness/Helplessness (HH) and Anxious Preoccupation (AP). A confirmatory hierarchical factor analysis on the 21 items included showed that FS measured positive adjustment to cancer and HH and AP measured negative adjustment. A differential adjustment hypothesis was proposed in order to explain the stability and instability of the measures of the diverse constructs. The three revised subscales showed the same validity pattern as the corresponding original scales, but the magnitude of the correlations was considerably improved with respect to the original subscales. The practical and the theoretical importance of FS, HH and AP are emphasized.

Adaptation, Psychological↗
PubMed1997

Microsatellite evolution--a reciprocal study of repeat lengths at homologous loci in cattle and sheep.

The application of microsatellites in evolutionary studies requires an understanding of the patterns governing their evolution in different species. The finding that homologous microsatellite loci are longer, i.e., containing more repeat units, in human and in other primates has been taken as evidence for directional microsatellite evolution and for a difference in the rate of evolution between species. However, it has been argued that this finding is an inevitable consequence of biased selection of longer-than-average microsatellites in human, because cloning procedures are adopted to generate polymorphic and, hence, long markers. As a test of this hypothesis, we conducted a reciprocal comparison of the lengths of microsatellite loci in cattle and sheep using markers derived from the bovine genome as well as the ovine genome. In both cases, amplification products were longer in the focal species, and loci were also more polymorphic in the species from which they were originally cloned. The crossing pattern that we found suggests that interspecific length differences detected at homologous microsatellite loci are the result of biased selection of loci associated with cloning procedures. Hence, comparisons of microsatellite evolution between species are flawed unless they are based on reciprocal analyses or on genuinely random selection of loci with respect to repeat length.

Animals↗
PubMed1994

Binding of the human papillomavirus E1 origin-recognition protein is regulated through complex formation with the E2 enhancer-binding protein.

The papillomavirus E1 and E2 proteins form heteromeric complexes and individually bind specific sequences within the viral origin of replication. The mechanism by which these proteins are recruited to the origin and the role of the E1/E2 complex in replication remain undefined. To examine the interplay of these replication proteins, we have analyzed the binding of human papillomavirus (HPV) type 31b E1 and E2 proteins to the origin of replication. Binding of E1 to the origin was increased by E2 proteins and required the presence of E2 binding sites. This increase was due to the formation of E1/E2 complexes which preferentially bound E2-responsive sequences, and the magnitude was determined by the relative affinity of the E2 binding sites. While the E1 protein alone bound an A/T-rich sequence at the HPV-31b origin with low affinity, complexes of E1 and E2 bound instead to E2 binding sites with high affinity. The E1/E2 complex bound a similar sequence as E2 homodimers, but only E2 homodimer binding induced a significant increase in hypersensitivity as indicated by DNase I footprinting. In the presence of excess E1, E1 proteins bound both the A/T-rich sequence and E2 binding sites through complex formation with E2. In E2 excess, E1/E2 complexes preferentially formed, and binding was specific for E2 sites. Therefore, changes in the relative amounts of E1 and E2 proteins can dramatically alter the pattern of binding of viral replication factors to the origin. These observations suggest a model whereby modulation of the relative levels of E1 and E2 during the viral life cycle may alter the pattern of origin binding and possibly episomal copy number.

Base Sequence↗
PubMed1994

Human colon cancer cell lines show a diverse pattern of nitric oxide synthase gene expression and nitric oxide generation.

A panel of human colonic adenocarcinoma cell lines was examined both for expression of mRNAs of the nitric oxide synthase (NOS) gene family and for evidence of enzymic activity based on citrulline and nitrite (NO2-) formation. Reverse transcription-polymerase chain reaction (RT-PCR), revealed that all lines (SW480, SW620, DLD-1 and WiDr) expressed mRNA for the Ca(2+)-dependent endothelial (e)NOS, while SW480 cells also expressed the Ca(2+)-dependent neuronal (n)NOS. The mRNA for the Ca(2+)-independent inducible (i)NOS was expressed both by cytokine-stimulated and by unstimulated SW480, SW620 and DLD-1 cells, but none was seen at any time in the WiDr cells. There was, however, little correlation between mRNA expression and enzymic activity based on citrulline and NO2- formation. Thus none of the cell lines exhibited measurable Ca(2+)-dependent NOS activity, while Ca(2+)-independent NOS activity was seen in all but the WiDr cells. Furthermore, DLD-1 cells generated citrulline with resultant NO2- formation only after stimulation with lipopolysaccharide (LPS) and/or cytokines, while SW480 and SW620 did so constitutively. Thus RT-PCR studies indicate that tumour cells of similar epithelial origin display a diverse pattern of NOS gene family expression, and parallel biochemical studies clearly indicate that such expression does not always result in measurable enzymic activity leading to the generation of NO.

Adenocarcinoma↗
PubMed1976

Responses of fibers in medial longitudinal fasciculus (MLF) of alert monkeys during horizontal and vertical conjugate eye movements evoked by vestibular or visual stimuli.

Extracellular recordings were obtained from 37 histologically identified MLF fibers near the trochlear nucleus in alert monkeys trained to perform a visual tracking task and subjected to adequate horizontal and vertical vestibular stimulation. The behavioral paradigm permitted independent quantitative assessment of a fiber's response to eye or head movements. 2. According to their discharge pattern, almost all MLF fibers were placed in one of two classes: 1) Horizontal burst-tonic fibers (n = 20). During both vestibular and visually evoked eye movements, burst-tonic fibers discharged in strict relation to horizontal eye movements, exhibiting a burst of activity prior to on-direction saccades and steady firing related to horizontal eye position during fixations. 2) Vertical vestibular plus eye-position fibers (n = 14). Vertical fibers discharged in relation to vertical head velocity in the absence of eye movements and in relation to vertical eye position in the absence of head movement, and paused with saccades in any direction. 3. The quantitative similarity of horizontal burst-tonic fiber discharge to that of ipsilateral medial rectus oculomotoneurons suggests that burst-tonic fibers provide the major excitatory synaptic drive to medial rectus motoneurons during conjugate eye movements of vestibular or visual origin. 4. The discharge pattern of vertical vestibular plus eye-position fibers is significantly different from that of oculomotoneurons, suggesting that additional neural processing of vertical fiber information must occur in the mesencephalon. 5. The functional dichotomy of horizontal and vertical MLF fibers and their contrasting discharge patterns provide new evidence for the anatomic and functional separation of horizontal and vertical eye movement mechanisms in the pons and mesencephalon, respectively.

Action Potentials↗