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PubMed1985

[Angiolymphoid hyperplasia with eosinophilia. Extensive form associated with thrombopenic purpura].

The authors report a case, on a 59-year-old female patient, of angiolymphoid hyperplasia with eosinophilia (AHE) associated to a thrombopenic purpura (TP) of which the evolution is parallel. The clinical aspect is made of sub-cutaneous nodules of various sizes (1 or 2 cm on an average) and of more superficial, erythematous, sometimes telangiectatic, pseudo-angiomatous nodules. There are (about) 25 nodules, located on the face, the neck, the arms and the thorax, sometimes pruriginous: the rest of the examination is negative excepting axillary and inguinal small size lymph nodes and of a dermographism. The anatomopathological examination in optical microscopy, shows a dermo-epidermal lymphocytic infiltrate with which mingle numerous eosinophilic leucocytes. The dermal vessels are very altered, with a swelling endothelium and a proliferation of endothelial and perithelial cells filling up in large part the vascular section. The biological investigation show essentially: a slight and altering hypereosinophilia (between 500 and 800/mm3); a low amount of blood-platelets (between 95,000 and 130,000/mm3); an increase of the seroconversion enzyme of angiotensin (75 UI; N less than 52 UI); are normal or negative: ESR, protein electrophoresis, immunological tests. The diagnosis of AHE is held back and the clinical evolution is done in several stages: under general corticotherapy (prednisone 1 mg/kg/j): progressive decrease of the nodules, but stopping of the therapy by the patient after 4 months; testing of treatment by thalidomide (100 mg/day) interrupted after 2 weeks because of the aggravation of the thrombopenia (25,000/mm3); occurrence of a thrombopenic purpura (TP) (amount of platelets 10,000/mm3) without a serious haemorrhagic syndrome, evolving in a parallel way to the outbreak of AHE.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Cortex Hormones↗
PubMedDate not supplied

Calcium antagonists reduce the extent of infarction in rat middle cerebral artery occlusion model as determined by quantitative magnetic resonance imaging.

The appearance and evolution of brain infarcts over 3 days following proximal occlusion of the left middle cerebral artery (MCA) in SHR rats were measured non-invasively by magnetic resonance imaging (MRI). Infarcts were clearly visible in coronal, T2 weighted brain sections, 24, 48 and 72 h after MCA occlusion in the left hemisphere, as areas of increased NMR signals. The infarcts were quantified by pixel counting in each section, the sum of 4 sections representing an accurate estimate of the total infarct size. The location and extent of infarction, determined by MRI, were found to be highly reproducible and correlated well with post-mortem histological and biochemical data. A neurological score, made every 24 h, paralleled the evolution of the infarct size, which culminated after 48 h. Pre- or post-treatment of MCA occluded rats with the dihydropyridine calcium antagonist PN 200-110 resulted in a substantial reduction of infarct size, determined by MRI 24, 48 and 72 h after infarction, compared to vehicle treated controls. These findings were corroborated by corresponding improvements of the neurological scores as well as histological and biochemical data. Post-treatment with nimodipine showed qualitatively similar effects. These results support the notion that calcium antagonists, through vascular and/or metabolic mechanisms, are effective in treating acute stroke. Since they were obtained in a chronic, relevant model of stroke with a method directly applicable also to humans, they should encourage further clinical studies with calcium antagonists.

Animals↗
PubMed2026

Tracking the shifting landscape of SARS-CoV-2 variants in Lebanon among healthcare workers and hospitalized patients.

UNLABELLED: Genomic surveillance of SARS-CoV-2 is critical for tracking viral evolution and informing public health responses. This study characterized variants circulating among healthcare workers (HCWs) and hospitalized patients in Lebanon between January 2022 and September 2024. A total of 530 SARS-CoV-2-positive nasopharyngeal swabs were collected from five Lebanese governorates and subjected to whole-genome sequencing. Correlations between variant circulation and a number of demographic and clinical variables were assessed. Most HCWs were female (64%), young adults (20-30 years, 39%), and had no comorbidities (97%). In contrast, hospitalized patients were mostly older adults (>60 years, 55.6%) with underlying conditions (77%). Early 2022 was marked by BA.1- and BA.2-like Omicron variants, followed by the predominance of BA.5-like lineages. In 2023, recombinant XBB sublineages became widespread. By 2024, these were largely replaced by next-generation variants, including JN.1 and KP.3.1.1. Despite differences in demographics and exposure risk, both groups showed parallel variant evolution. These findings reflect global and regional patterns and highlight the dynamic nature of SARS-CoV-2 circulation in Lebanon. IMPORTANCE: This study provides a comprehensive snapshot of SARS-CoV-2 variant evolution in Lebanon between 2022 and 2024, focusing on healthcare workers and hospitalized patients. By combining genomic and clinical data, it reveals how successive Omicron subvariants emerged and spread within key population groups. The detection of diverse and evolving lineages, including XBB recombinants and next-generation variants such as JN.1, underscores the ongoing antigenic drift of SARS-CoV-2. These insights reinforce the value of continued genomic surveillance for pandemic preparedness, especially in regions where data remain limited. Understanding local variant dynamics can guide targeted vaccination strategies and health policy decisions.

Humans↗
PubMed1997

Effect of hypothermia on microglial reaction in ischemic brain.

Intra-ischemic hypothermia is known to protect neurons against ischemic injury. Microglial cells have been shown to become activated following ischemia and are speculated to play significant roles in the evolution of ischemic neuronal injury. In this study, we examined the effect of intra-ischemic hypothermia on the microglial reaction in the hippocampus following transient forebrain ischemia produced in gerbils by 10 min bilateral carotid occlusion at 30 degrees C or at 37 degrees C, followed by normothermic reperfusion for 1-7 days. Microglial cells were visualized by histochemical staining with isolectin-B4 from Griffonia simplicifolia. Brains subjected to normothermic ischemia showed activation of microglia at 1 day post-ischemia; this increased with further recirculation, becoming intense by 3 days and diminished by 7 days. Ischemia under hypothermic conditions was not associated with activation of microglia, and these brains showed no significant neuronal damage, whereas the brains subjected to normothermic ischemia showed extensive neuronal necrosis in the CA1 region after 1 and 7 days reperfusion. The presence of activated microglial cells in the CA1 region prior to and in parallel with evolution of ischemic neuronal damage, the lack of such activation in brains subjected to the neuroprotective action of intra-ischemic hypothermia, together with the known potential capability of microglial cells to release cytotoxic substances appear to indicate that these cells could contribute significantly to ischemic neuronal necrosis.

Animals↗
PubMed2002

Evidence for parallel ecological speciation in scincid lizards of the Eumeces skiltonianus species group (Squamata: Scincidae).

We identify instances of parallel morphological evolution in North American scincid lizards of the Eumeces skiltonianus species group and provide evidence that this system is consistent with a model of ecological speciation. The group consists of three putative species divided among two morphotypes, the small-bodied and striped E. skiltonianus and E. lagunensis versus the large-bodied and typically uniform-colored E. gilberti. Members of the group pass through markedly similar phenotypic stages during early development, but differ with respect to where terminal morphology occurs along the developmental sequence. The morphotypes also differ in habitat preference, with the large-bodied gilberti form generally inhabiting lower elevations and drier environments than the smaller, striped morphs. We inferred the phylogenetic relationships of 53 skiltonianus group populations using mtDNA sequence data from the ND4 protein-coding gene and three flanking tRNAs (900 bp total). Sampling encompassed nearly the entire geographic range of the group, and all currently recognized species and subspecies were included. Our results provide strong evidence for parallel origins of three clades characterized by the gilberti morphotype, two of which are nested within the more geographically widespread E. skiltonianus. Eumeces lagunensis was also nested among populations of E. skiltonianus. Comparative analyses using independent contrasts show that evolutionary changes in body size are correlated with differences in adult color pattern. The independently derived association of gilberti morphology with warm, arid environments suggests that phenotypic divergence is the result of adaptation to contrasting selection regimes. We provide evidence that body size was likely the target of natural selection, and that divergences in color pattern and mate recognition are probable secondary consequences of evolving large body size.

Adaptation, Biological↗
PubMed1983

Alterations of noradrenaline and serotonin uptake and metabolism in chronic cobalt-induced epilepsy in the rat.

The high affinity uptake of noradrenaline and serotonin, and the concentrations of these monoamines and their metabolites, have been measured in the perifocal cortical area at various stages of the evolution of cobalt-induced epilepsy in the rat. Noradrenaline uptake was maximally reduced at days 8-10 after cortical cobalt application, a time corresponding to the onset of epileptic discharges; it remained diminished during the spiking activity period of the focus (days 14-20) and was back to normal values at day 40, at which time the epileptic syndrome had disappeared. Serotonin uptake was also diminished at days 8-10 but to a lesser extent than was noradrenaline uptake. In the homotopic cerebral cortex contralateral to cobalt application, noradrenaline uptake was reduced at day 10 only and to a lesser extent than in the perifocal area, whereas serotonin uptake was unaffected. Kinetic analysis of the cobalt-induced monoamine uptake alterations at day 10 revealed a diminution of the maximal velocity with no change in the Km. Noradrenaline and dihydroxyphenylethyleneglycol concentrations in the perifocal area were also maximally reduced at days 8-10 but were unaffected at day 2 and day 40 post cobalt application. A reduction of serotonin levels in the perifocal area was observed only at days 8-10 while 5-hydroxyindoleacetic acid remained unaffected throughout the time period studied. The levels of these monoamines and their metabolites were unchanged in the homotopic contralateral cortex 2-40 days after cobalt application. These results indicate that cortical cobalt application induces alterations of the biochemical indices of the density of noradrenaline-containing terminals that closely parallel the evolution of the epileptic syndrome. These data further emphasize the important role of the cortical noradrenergic system in cobalt-induced epilepsy.

Animals↗
PubMed1999

Bi-penta-bi-decaradial symmetry: A review of evolutionary and developmental trends in holothuroidea (echinodermata)

Holothuroidea, comprising the sea cucumbers, is the least studied class of extant echinoderms, yet this group possesses a wealth of features of potential interest to developmental and evolutionary biologists. Holothuroids include the most morphologically derived echinoderms, including pelagic species and spheroid, plated taxa with mouth and anus adjacent at the end of a long, flexible stalk. To begin investigating this diversity of body form, we first estimated evolutionary relationships in the class Holothuroidea based on maximum parsimony analyses of 1,075 nt of the nuclear small subunit rDNA (for six species in four orders) and on 52 informative morphological characters (for the 25 extant families). Both the morphological and molecular evidence suggests almost an inversion of the prevailing higher level classification. Character-state optimizations indicated that pronounced adult bilateral symmetry evolved three times. In one group even a regain of secondary radial symmetry is found. Respiratory trees, structures unique to holothuroids, are a relatively late innovation, are ectodermally derived, and are bilaterally symmetric, supporting the possibility that the secondary gain of bilateral symmetry in holothuroids is ectodermally derived analogous to, say, the derivation of vertebrate limb dorso-ventral axis. The test of imbricating plates found in 10% of living holothuroids is apparently not homologous with that of other heavily armored echinoderms, evolving much later and at least twice. Indirectly developing larvae, auriculariae, occur in two evolutionarily disparate clades and unlike echinoids comprise a minority of clades. We suggest that this implies the parallel convergent evolution of this larval type or, more speculatively, some form of retention of developmental constraints. J. Exp. Zool. (Mol. Dev. Evol.) 285:93-103, 1999. Copyright 1999 Wiley-Liss, Inc.

Journal Article↗
PubMed1986

Effects of silica on lung collagen.

A single intratracheal injection of 50 mg crystalline silica (quartz) into rats produces silicosis. This animal model may be used to study collagen metabolism during the early, middle, and late phases of lung injury, corresponding respectively to the stages of lung injury, development of discrete granulomas, and development of mature silicotic nodules. The early phase is characterized by a rapid increase in the rate of synthesis of lung collagen (within one week of instillation) and increased deposition of excess lung collagen (significant increases within two weeks of instillation). Later phases are characterized by a continuing increase in deposition of excess lung collagen for at least one year after instillation. Silica-induced fibrosis is unique among all the animal models (and in most human fibrotic diseases) thus far examined, in that the excess collagen deposited in the lung contains normal ratios of the two major collagen types of the lung: types I and III. This collagen is nonetheless biochemically different from normal lung collagen. There are reproducible and characteristic differences in the intermolecular cross-links of the collagen in lungs from rats injected with silica. Within one month of silica instillation (the earliest time point examined thus far), an increased hydroxylysine content of collagen can be appreciated. The reducible dysfunctional cross-links are also more likely to be derived from hydroxylysine (i.e. the ratio of dihydroxylated to monohydroxylated cross-links increases). Within four months of silica instillation (and increasingly thereafter), increased amounts of the mature trifunctional cross-link hydroxypyridinium (derived from three residues of hydroxylysine) can also be appreciated, seemingly paralleling the evolution of mature silicotic nodules in these lungs. These changes in cross-linking of lung collagen seem to be common to all the animal models of pulmonary fibrosis examined, and are also consistent with changes occurring in human fibrotic lungs. Preliminary observations suggest that the locus of cross-linking remains the same: hydroxylysine replaces lysine in the primary structure of a specific collagen alpha chain to form the altered cross-links. Thus, there may be molecular markers for the collagen of fibrosis in diseased lungs.

Animals↗
PubMed1983

Immunopathogenesis of experimental Chagas' disease in mice: damage to the autonomic nervous system.

Infection of mice with Trypanosoma cruzi produces pathological change which in many ways parallels the evolution of Chagas' disease in human patients. An essential element in this experimental pathology is the intense denervation observed during the resolution of acute-stage parasitaemia. Host cells, from a variety of tissues, have been shown to absorb parasite antigens and thus to become targets for the hosts' own anti-parasite immune response. The definition of common antigenic determinants, shared by T. cruzi and human neuronal cells, might explain why the electrical conduction systems and the autonomic nervous system are especially vulnerable to the postulated autoimmune process. We have the models, the tools and the hypotheses, and now we await the proof.

Animals↗
PubMed1989

Decreased glucose utilization in the striatum and frontal lobe in probable striatonigral degeneration.

Nine positron emission tomography studies of regional cerebral glucose metabolism were performed in 7 patients with probable striatonigral degeneration, a disorder characterized by parkinsonian features and absent or poor response to L-dopa. When compared with values obtained in normal volunteers, mean cerebral glucose metabolism was slightly reduced in subjects with striatonigral degeneration who, in addition, had a marked (20.5%, +/- 3 SD) relative hypometabolism in putaminal and caudate nuclei. Significant hypometabolism was also found in motor/premotor as well as in prefrontal cortex. In 2 subjects who were studied twice a deterioration of relative striatal metabolism paralleled clinical evolution. Magnetic resonance imaging disclosed the presence of abnormal iron deposits in the putamen in all cases but showed no cortical anomalies. These results suggest that positron emission tomography with [18F]fluorodeoxyglucose may provide an index of cell and processes degeneration in the striatum in striatonigral degeneration and is able to detect functional deficits in frontal cortex. The presence of striatal hypometabolism might be a predictor of a poor response to L-dopa.

Aged↗
PubMed1986

Epstein-Barr virus-related ultrastructural modifications of plasma membrane during B-cell transformation.

Ultrastructural modifications are described in the plasma membrane of in vitro established human B cells. By the freeze-fracture technique, intramembrane particles (IMPs) are quantified in B lymphocytes following Epstein-Barr virus (EBV) transformation in vitro, and in B-lymphoma (Burkitt-type) cells, either positive or negative for EBV genome. Analysis shows an overall increase in IMP density as compared to normal controls. Differences are observed between the protoplasmic and exoplasmic faces of fractured membranes as well as among in vitro transformed and clearly neoplastic cells. Results indicate that conformational changes in IMP distribution parallel neoplastic evolution of transformed cells.

B-Lymphocytes↗
PubMed1993

Cancer in Kampala, Uganda, in 1989-91: changes in incidence in the era of AIDS.

Re-establishment of the cancer registry in Kyadondo County, Uganda, has allowed estimation of incidence rates for the period September 1989 to December 1991. The results are compared with earlier data from the same area, and from other African cancer registries. The most striking feature is the emergence of Kaposi's sarcoma as the leading cancer in males (almost half of all registered cases) and the second most frequent (17.9%) in females. This parallels the evolution of the epidemic of AIDS. There were also marked increases in the incidence of both oesophageal and prostatic carcinoma, while the incidence of cancer of the penis and the urinary bladder declined, possibly as a result of improved standards of hygiene. In females, the incidence of cancer of the cervix has more than doubled since the 1950s, and is now among the highest recorded in the African continent.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Adrenal medulla in neural grafting and neural plasticity.

The recent history of neural transplantation using the adrenal medulla parallels an evolution in our thinking about neural grafting as a therapeutic approach to treat neurodegenerative diseases such as Parkinson's disease. Initially, neural grafting was an approach to study development and regeneration. With the discovery that adrenal chromaffin cell grafts would ameliorate some of the motor deficits associated with the loss of striatal dopamine, adrenal grafts were used to provide dopamine to the dopamine-depleted striatum. However, subsequent studies showed poor chromaffin cell survival unless trophic factors were present at the site of transplantation. These experiments lead to the appreciation of the complex interactions between neurotrophic factors, inflammatory cytokines, the grafted tissue, and the host brain's response. Thus, we find ourselves again using neural transplantation as an approach to help us better understand central nervous system plasticity and the features this plasticity shares in common with development and regeneration.

Adrenal Medulla↗
PubMed1994

Murine models of Sjögren's syndrome.

Autoimmune MRL/lpr, MRL/+, and NZB/W mice all develop lacrimal gland inflammatory lesions, which consist of focal mononuclear inflammatory cell infiltrates. Each strain has a different immunocytochemical profile, which appears to be related to the underlying immunologic defects present in that mouse. The appearance of these lesions parallels the evolution of the systemic autoimmune disease. The lesions are dynamic over time with the early appearance of CD4+ T cells (helper T cells) for each strain. Subsequently, there is an accumulation of B cells over time in MRL/+ and NZB/W mice. In the two more rapidly evolving mouse models, MRL/lpr and NZB/W, there is a progressive decline in the percentage of CD8+ cells. Conversely, in the slowly evolving MRL/+ lacrimal gland lesions, there is a persistent and unchanging percentage of CD8+ T cells (suppressor/cytotoxic T cells). Autoimmune mice provide models for the human disorder Sjögren's syndrome and a mechanism for better understanding the immunopathogenesis of autoimmune lacrimal gland disease.

Animals↗
PubMed1992

Short-term neurophysiological monitoring in multiple sclerosis bouts. Evaluation of steroid treatment.

Visual (VEP) and brainstem auditory (BAEP) evoked potentials (EP) were recorded in 21 multiple sclerosis (MS) patients in acute relapse before and after steroid treatment. VEPs were abnormal in 14/21 patients and BAEPs in 10/21 patients before treatment. In 4 patients with acute optic neuritis (ON), an improvement of VEPs paralleled clinical evolution in 3 cases. Substantial and contrasting changes in VEPs or BAEPs, with no clinical counterpart, were related to a spontaneous fluctuation of EPs in acute relapses of MS. These changes suggest frequent subclinical (multifocal and, possibly, sequential) central nervous system involvement in MS bouts. Group analysis showed nonsignificant changes in EP parameters before and after treatment. Our results indicate that evoked potentials (EPs) are of limited value for monitoring the short-term effect of steroid treatment in MS in bouts.

Adult↗
PubMed2000

Evolutionary analysis of the ErbB receptor and ligand families.

We have compared all available deduced protein sequences of the ErbB family of receptors and their ligands. Analysis of the aligned sequences of the receptors indicates that there are some differences in the receptors that are specific to invertebrates. In addition, comparison of the vertebrate ErbB receptors suggest that a gene duplication event generated two ancestral receptors, the ErbB3/ErbB4 precursor and the ErbB1/ErbB2 precursor. Subsequent gene duplications of these precursors generated the four receptors present in mammals. Analysis of the sequences for the known ligands of the ErbB receptors suggests that the vertebrate ligands segregate into the ErbB1 ligands and the ErbB3/ErbB4 ligands, paralleling the evolution of the receptors; however, it is difficult to ascertain any correlation between the invertebrate and the vertebrate ligands. Even though ErbB3 is kinase-impaired, there is significant conservation of the kinase domain within the vertebrate lineage (human, rat, and F. rubripes), suggesting some function for this domain other than kinase activity, such as mediating protein-protein interactions that are involved in receptor dimerization and/or activation of the kinase domain of the heterodimerization partner. To date, no ligand for ErbB2 has been identified, and comparison of the extracellular domains of ErbB2 reveals two regions that are not conserved across the mammalian species. These two regions of divergence align with sequences in ErbB1 that have been shown to be proximal to the amino-terminus and to the carboxyl-terminal region, respectively, of bound EGF. Further, one of these regions contains an insertion, relative to the other members of the mammalian ErbB family, which might affect the ligand binding site and provide a structural basis for this receptor's apparent inability to bind ligand independently.

Amino Acid Sequence↗
PubMed1985

Infectious antecedent of immunoblastic lymphoma. Progressive immunosuppression in a patient with lymphogranuloma venereum.

Angioimmunoblastic lymphadenopathy is a nonmalignant disease of unknown etiology often progressing to immunoblastic lymphoma. Immunologic deficiency is evident in these patients as well as in those with various infections found in association with the acquired immune deficiency syndrome (AIDS). This report describes a previously healthy young woman in whom angioimmunoblastic lymphadenopathy developed in association with lymphogranuloma venereum, with progressive loss of immunologic competence. This deterioration paralleled the evolution of angioimmunoblastic lymphadenopathy into a rapidly fatal immunoblastic lymphoma.

Adult↗