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Abstract: Aims: Isolate and characterize a laccase‐encoding gene (lac I) of Phlebia brevispora BAFC 633, as well as cloning and expressing cDNA of lac I in Pichia pastoris. And to obtain a purified and characterized recombinant laccase to analyse the biotechnological application potential. Methods and Results: Lac I was cloned and sequenced, it contains 2447 pb obtained by PCR and long‐distance inverse PCR. Upstream of the structural region of the laccase gene, response elements such as metals, antioxidants, copper, nitrogen and heat shock were found. The coding region consisted of a 1563‐pb ORF encoding 521 amino acids. Lac I was functionally expressed in P. pastoris and it was shown that the gene cloned using the α‐factor signal peptide was more efficient than the native signal sequence, in directing the secretion of the recombinant protein. Km and highest kcat/Km values towards ABTS, followed by 2,6‐dimethylphenol, were similar to other laccases. Lac I showed tolerance to NaCl and solvents, and nine synthetic dyes could be degraded to different degrees. Conclusions: Lac I‐encoding gene could be successfully sequenced having cis‐acting elements located at the regulatory region. It was found that lac I cDNA expressed in P. pastoris using the α‐factor signal peptide was more efficient than the native signal sequence. The purified Lac I exhibited high tolerance towards NaCl and various solvents and degraded some recalcitrant synthetic dyes. Significance and Impact of the Study: The cis‐acting elements may be involved in the transcriptional regulation of laccase gene expression. These results may provide a further insight into potential ways of optimizing fermentation process and also open new frontiers for engineering strong promoters for laccase production. The Lac I stability in chloride and solvents and broad decolorization of synthetic dyes are important for its use in organic synthesis work and degradation of dyes from textile effluents respectively. [ABSTRACT FROM AUTHOR]

Introduction: The development of an extrapyramidal syndrome (EPS) is assumed to be a potential and important consequence of organophosphate poisoning (OP). Even though its causal relationship is firmly established, the information available in the literature regarding the orientation to be given is scarce, and its approach remains shrouded in a significant degree of uncertainty. Catatonia, as a neuropsychiatric condition, may present a marked overlap with the set of extrapyramidal symptoms developed after OP. Does the overlap between the symptoms seen in catatonia and in EPS make differential diagnosis fundamental or does it have no relevance in relation to the approach to be established?. Objectives: To discuss the therapeutic approach to be implemented in the extrapyramidal symptoms resulting from OP and reflect on the overlap between catatonia and EPS. Methods: Presentation of a clinical case and review of the literature. Results: A 50-year-old woman with major depressive disorder developed a condition marked by exuberant extrapyramidal symptoms 3 weeks after OP. Significant stiffness, tremor, dysphagia and facial hypomimia were some of the symptoms observed. Therapy was started with amantadine 100mg daily, with complete resolution of the symptoms after 5 days. Follow-up revealed reversal of extrapyramidal symptoms, in the absence of any neuroimaging changes or any other neuropsychiatric manifestations. Conclusions: The possible overlap between catatonia and EPS is remarkable. The two conditions, regardless of their differentiation, may benefit from an identical approach using dopaminergic drugs. The use of amantadine, even in low doses, may be an option in the rapid reversal of extrapyramidal symptoms resulting from OP. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the mycoremediation of polychlorinated biphenyls (PCBs) by either single cultures or binary consortia of Pleurotus pulmonarius LBM 105 and Trametes sanguinea LBM 023., Methods and Results: PCBs tolerance, removal capacity, toxicity reduction and ligninolytic enzyme expression were assessed when growing single culture and binary consortium of fungus in 217 mg l -1 of a technical mixture of Aroclor 1242, 1254 and 1260 in transformer oil. A decrease in tolerance and variation in ligninolytic enzyme secretion were observed in PCB-amended solid media. Pleurotus pulmonarius LBM 105 mono-culture was able to remove up to 95·4% of PCBs, whereas binary consortium and T. sanguinea LBM 023 could biodegrade about 55% after 24 days. Significant detoxification levels were detected in all treatments by biosorption mechanism., Conclusions: Pleurotus pulmonarius LBM 105 in single culture had the best performance regarding PCBs biodegradation and toxicity reduction. Ligninolytic enzyme secretion changed in co-culture., Significance and Impact of the Study: The evaluation of PCBs bioremediation effectiveness of basidiomycetes consortium in terms of PCB removal, toxicity and ligninolytic enzyme production to unravel the differences between using individual cultures or consortium has not been reported. The results from this study enable the selection of P. pulmonarius LBM 105 mono-culture to bioremediate PCBs as it showed higher efficiency compared to binary consortium with T. sanguinea LBM 023 for potential decontamination of PCB-contaminated transformer oil., (© 2021 The Society for Applied Microbiology.)

Introduction: Epilepsy is the most commonly occurring neurological disorder in the world. The study of structural brain lesions is important to understand the secondary complications. In Honduras there is little information on this topic., Aim: To determine the characteristics and proportion of structural brain lesions in paediatric patients with focal epilepsy at the Hospital Escuela Universitario., Patients and Methods: A descriptive, cross-sectional, retrospective-prospective study. The study population consisted of 162 paediatric patients with focal epilepsy who were treated in the paediatric neurology outpatient department between January 2015 and June 2016. On applying the eligibility and exclusion criteria, the universe of study comprised 102 patients with focal epilepsy., Results: 41% of the patients with focal epilepsy presented a structural lesion. The main locations of the structural lesions were the parietal lobe (12.8%), the occipital lobe (10.8%) and the frontal lobe (10.8%). An association was found between the presence of structural brain lesions and the presence of uncontrolled seizures, with statistical significance. The attributable risk was calculated and it was found that among patients with uncontrolled seizures, 67% had a structural lesion in the imaging study., Conclusions: The presence of uncontrolled seizures is associated to the presence of structural lesions in imaging studies, with a high attributable risk. Leukomalacia and cerebral ischaemia were the main findings that were reported. The predominant structural lesions in paediatric patients with focal epilepsy in the population studied are those related to events that take place during the peripartum period.

This study was aimed to examine cholesteryl ester transfer protein (CETP), apolipoprotein AI and CIII gene polymorphisms, and to verify whether these genetic determinants are associated with the prevalence of myocardial infarction (MI) or type 2 diabetes. The TaqIB restriction fragment length polymorphism (RFLP) in intron I of the CETP gene, the MspI in the third intron of the APOAI gene, and also SstI in the 3' untranslated region of the APOCIII gene were determined using standard methods. The prevalence of these polymorphisms was compared between diabetic (n = 119), and non-diabetic (n = 100) middle-aged individuals of both sexes. We found a higher prevalence of the B2B2 genotype of the CETP gene among diabetics than that observed in non-diabetics (P < 0.05), and a lower prevalence of this genotype among patients with previous MI (P < 0.02). The MspI polymorphisms of the APOAI gene showed that M1++ genotype was found mainly in diabetic patients (P < 0.04). Conversely, the SstI polymorphism of APOCIII gene was not significantly associated with either MI or diabetes. Therefore, among these genetic polymorphisms, TaqIB of CETP and MspI of apolipoprotein AI appeared to help significantly to identify diabetic individuals. In particular, the former may have an additional role in the primary prevention of coronary disease.

C1qR(P) is a type I cell surface glycoprotein that has been shown to enhance ingestion of suboptimally opsonized targets by phagocytes in vitro. In this study, we developed and characterized polyclonal antibodies to study the tissue distribution of this receptor targeted to either the N- or C-terminal portion of the molecule. C1qR(P) was detected in vascular endothelial cells and in a subset of pyramidal neurons in the brain, as well as neutrophils, but it was absent in most tissue macrophages. Analysis of in vitro differentiation of blood monocytes to dendritic cells demonstrated a down-regulation of the receptor as monocytes differentiate to dendritic cells, providing a possible explanation for the lack of reactivity of these cells in tissue. The predominant presence of C1qR(P) in endothelial cells, while compatible with a phagocytic role in host defense and/or clearance of cellular material, suggests other possible novel roles for this receptor.

It is known that 5-HT receptors have significant roles in nociceptive and motor functions. We have compared the cellular localization of the mRNAs encoding serotonin 5-HT(2A,) 5-HT(2C,) 5-HT(3) receptor subtypes within different levels of the rat spinal cord and medulla. In the spinal cord, 5-HT(2C) receptor mRNA is expressed at high levels in most of the gray matter, except for lamina II. In contrast, 5-HT(2A) receptor mRNA is expressed exclusively in lamina IX. 5-HT(3) receptor mRNA has a low level and diffuse pattern of expression increasing towards the ventral horn. In both gray and white matter, there is a characteristic presence of a few highly stained cells. For each subtype, the expression pattern is similar in all four levels of the spinal cord. In the medulla, 5-HT(2C) receptor mRNA is at high levels in many nuclei including the hypoglossal nucleus, the gigantocellular reticular nucleus alpha and the parvocellular reticular nucleus alpha, the spinal nucleus of the trigeminal tract, the facial, and the dorsal medullary reticular field. Moderate to low levels of expression are seen in the spinal vestibular nucleus, the vagus, the solitary nuclei and the raphe. 5-HT(2A) receptor is expressed at high levels in some nuclei such as the hypoglossal nucleus, the intercalate nucleus, the inferior olive and the lateral reticular nucleus. Moderate to low levels of expression are seen in the facial, the medial vestibular nuclei, the nucleus ambiguous, the vagus, and the gigantocellular reticular nucleus. 5-HT(3) receptor mRNA is present at low levels in most of the nuclei examined, with a few scattered strongly labeled cells. The results show a distinct distribution of the three subtypes of receptors supporting their physiological roles and will help to understand the mechanisms of nociception and motor function.

Mutations in the amyloid precursor protein (APP) and presenilin-1 and -2 genes (PS-1, -2) cause Alzheimer's disease (AD). Mice carrying both mutant genes (PS/APP) develop AD-like deposits composed of beta-amyloid (Abeta) at an early age. In this study, we have examined how Abeta deposition is associated with immune responses. Both fibrillar and nonfibrillar Abeta (diffuse) deposits were visible in the frontal cortex by 3 months, and the amyloid load increased dramatically with age. The number of fibrillar Abeta deposits increased up to the oldest age studied (2.5 years old), whereas there were less marked changes in the number of diffuse deposits in mice over 1 year old. Activated microglia and astrocytes increased synchronously with amyloid burden and were, in general, closely associated with deposits. Cyclooxygenase-2, an inflammatory response molecule involved in the prostaglandin pathway, was up-regulated in astrocytes associated with some fibrillar deposits. Complement component 1q, an immune response component, strongly colocalized with fibrillar Abeta, but was also up-regulated in some plaque-associated microglia. These results show: i) an increasing proportion of amyloid is composed of fibrillar Abeta in the aging PS/APP mouse brain; ii) microglia and astrocytes are activated by both fibrillar and diffuse Abeta; and iii) cyclooxygenase-2 and complement component 1q levels increase in response to the formation of fibrillar Abeta in PS/APP mice.

Microglial activation has been associated with several degenerative diseases of the central nervous system (CNS). One consequence of activation is the induction of a more efficient phagocytic response, and it is therefore important to determine what factors regulate microglial phagocytosis and whether this capacity influences the progression of neurodegenerative changes. Previous studies have demonstrated that complement component C1q enhances Fc receptor- and CR1-mediated phagocytosis in cells of the myeloid lineage via a cell surface receptor, C1qRp. Because C1q has been found in the area of lesions in several degenerative CNS diseases, the current investigations were carried out to characterize the effects of C1q on microglial phagocytosis. Neonatal rat microglia were shown to express C1qRp, as assessed by flow cytometry and immunocytochemistry. Interaction of these cells with substrate-bound C1q was shown to enhance both FcR-and CR1-mediated phagocytosis two- to fourfold. In addition, introduction of an antibody raised against the carboxy-terminal, cytoplasmic domain of C1qRp into microglia by electroporation markedly diminished the ability of C1q to enhance uptake of IgG-coated targets, whereas nonspecific IgG had no such effect. These results suggest that C1q in areas of active degeneration may promote the phagocytic capacity of microglia via interaction with microglial C1qRp.

Extracellular deposits of fibrillar beta-amyloid are a characteristic neuropathology of Alzheimer's disease (AD). We have developed a novel antibody to a hypothesized "older isomer" of the amyloid protein. This antibody, raised against a synthetic beta-amyloid peptide containing isoaspartic acid at position 7 (isoaspartic-7-Abeta), reacts with isoaspartic-7-Abeta, a nonenzymatic modification found in long-lived proteins. Plaques stained with this antibody are thioflavine positive and are found throughout the frontal and entorhinal cortices of AD cases. In frontal cortex, isoaspartic-7-Abeta plaques are clustered but have a widespread distribution in all cortical layers. Isoaspartic-7-Abeta is found primarily in the core of individual plaques surrounded by nonisomerized amyloid. Activated microglia are associated with plaques containing isomerized and nonisomerized amyloid. In contrast to AD, isoaspartic-7-Abeta plaques in Down's syndrome (DS) cases are found primarily in the superficial layers of frontal cortex. Using image analysis isoaspartic-7-Abeta deposition was correlated with dementia severity in AD and with age in DS. The results indicate that this antibody against altered aspartyl amyloid could be a useful indicator of the age of amyloid plaques., (Copyright 1999 Academic Press.)

An antiserum that recognizes a sequence from the putative third cytoplasmic loop of the m2 subtype of muscarinic receptors (mAchR) has been raised and used to map the cellular distribution of this subtype in rat olfactory bulb. The antiserum was obtained by injecting BALB/C mice with a BSA-conjugated synthetic peptide whose sequence corresponded to amino acids 240-259 of the porcine cardiac m2 mAChR gene. Antibodies recognized the synthetic peptide in ELISA screening and labelled a single band corresponding to the peak of [3H]PrBCM-labelled heart mAchRs in immunoblots. Immunostaining of olfactory bulb, a region of the brain enriched in this muscarinic receptor subtype, showed that the antibodies labelled cell bodies and multiple dendritic processes. Broad fluorescent labelling throughout cell bodies was consistent with binding to the cytoplasmic face of the surface membrane, in support of the predicted cytoplasmic loop structure. m2-Positive cells throughout the bulb were sparsely distributed in different layers representing small subpopulations of the cells in each region: glomeruli, 6%; external plexiform layer, 16%; inner plexiform and granule cell layer, 3%. The results show that antibodies against specific sequences of different muscarinic receptor subtypes can be used to localize subtypes in situ, that the m2 subtype within the rat olfactory bulb is broadly distributed, and that the m2 subtype can occur postsynaptically in this central nervous system (CNS) region. The mapping of m2-positive cells in olfactory bulb may be of particular interest because loss of this subtype and degeneration of the olfactory system have been observed in Alzheimer's disease.

Muscarinic receptors are altered by sulfhydryl reagents. Arsenic compounds, which have been used as insecticides, exert their toxic effects by combining with sulfhydryl groups. We compared the action of arsenicals and other sulfhydryl reagents on the muscarinic receptor from invertebrate and vertebrate species (locust and rat). Disulfide-reducing reagents dithiothreitol (DTT) and British Anti-Lewisite (BAL), but not arsenicals, inhibited [3H]quinuclidinyl benzilate ([3H]QNB) binding. However, after disulfide reduction, arsenicals caused a further inhibition of muscarinic binding. The effect of DTT + arsenicals was largely irreversible. The locust receptors were more sensitive to the action of both disulfide reagents either in the absence or presence of arsenicals than the rat receptors. The sulfhydryl reagent p-chloromercuric benzoate (PCMB) was more effective at inhibiting the locust receptors than the rat receptors, but addition of arsenicals did not cause further inhibition in either the locust or rat receptors. In locust, DTT + cacodylate and DTT + arsenite caused a reduction in the number of sites without modifying the affinity of [3H]QNB binding. In rat, DTT + arsenite caused a decrease in the affinity, while DTT + cacodylate caused a decrease in the affinity of [3H]QNB binding and its number of sites. Competition experiments after DTT + cacodylate showed that the IC50 and the Hill coefficient (nH) remained unchanged in the locust. In the rat, the IC50 for atropine was increased without alteration in the nH, and both parameters were increased for carbachol. These results are explained assuming that the binding site of the locust receptor has a disulfide group similar to that of the mammalian receptor, but that the hydrophobic interactions within the binding site are weaker in the locust receptor. The higher sensitivity of the insect receptor to sulfhydryl reagents could be of interest for developing methods of pest control.

A crude synaptosomal membrane fraction of rat cerebral cortex was submitted to binding with [(3)H]prazosin for ?(1) adrenoceptors. Methylation with 100 ?M S-adenosyl methionine (SAM) resulted in a 43 +/- 7% increase in the binding of 3 nM [(3)H]prazosin. The effect of SAM was stimulated by 8mM Ca(2+), and was not inhibited by S-adenosyl-homocysteine. Time incubation, as well as concentration curves, showed a biphasic effect of SAM. In saturation experiments SAM caused a large increase in the B(max) with little effect on the K(D). Displacement curves with noradrenaline showed that the affinity and proportion of agonist biding sites was not altered by SAM. These findings are discussed on the basis of what is known about the action of SAM on ? adrenoceptors and benzodiazepine receptors. It is concluded that the effect of SAM on ?(1) adrenoceptors is probably mediated by a direct action on the lipoprotein structure of the membrane and not on an effect of methyltransferases.

In different brain regions of the rat we studied the effect of chronic feeding with the organochlorine insecticides p,p'-DDT and gamma-HCH on the cholinergic muscarinic receptors. Using [3H]quinuclidinyl benzylate binding to membranes from cerebral cortex, medulla pons, diencephalon, and cerebellum it was found that the two insecticides produced a decrease in the number of muscarinic receptor sites in cerebellum; while gamma-HCH also reduced these receptors in diencephalon. In both cases no changes in receptor affinity were observed. It is suggested that the chronic treatment with these organochlorine insecticides may cause an alteration in cholinergic transmission leading to a down regulation of the muscarinic receptor in certain brain regions.

We have compared the effect of ethanol, a membrane perturbant, on the muscarinic binding sites in neural membranes from a vertebrate (rat) and an insect (locust). The binding of the muscarinic antagonist [3H]quinuclidinyl benzilate ([3H]QNB) to both rat and locust neural membranes was inhibited by ethanol at 10-500 mM concentrations; but this inhibition was greater in the locust. Ethanol (500 mM) increased the apparent dissociation constant (KD') of [3H]QNB binding to rat membranes from 0.13 +/- 0.01 nM in control to 0.20 +/- 0.02 nM; there was also an small but significant reduction in the number of binding sites Bmax. In locust, 500 mM ethanol reduced the Bmax of [3H]QNB binding from 590 +/- 30 in control to 320 +/- 40 pmol/g protein; no significant alteration in the KD was detected. The dissociation rate constant (koff) of [3H]QNB increased from 0.020 +/- 0.003 in controls to 0.031 +/- 0.004 (min-1) in the presence of 500 mM ethanol, the association rate constant (Kon) did not change significantly. In locust, 500 mM ethanol did not affect either Kon or Koff. Competition experiments revealed that the binding affinities of both the agonist carbamylcholine and the antagonist atropine to the rat membranes were reduced in the presence of ethanol. In contrast, ethanol caused no alteration in the binding affinities of these ligands to the locust membranes. This differential effect of ethanol on rat and locust muscarinic binding suggests a difference in the hydrophobic domains and/or the membrane interactions of the muscarinic receptors in the two species.

The injection of Bordetella pertussis, inactivated by merthiolate, causes a 2-fold increase in the IC50 of carbamylcholine (carbachol) in displacing [3H];-L(-) quinuclidinyl benzilate binding ([3H]QNB) to the receptor. In control animals, 50 microM Gpp(NH)p causes a 6-fold decrease in the affinity of carbachol binding, whereas after vaccination the reduction is only 1.6-fold. After pertussis treatment there is no alteration in the affinity and number of [3H]QNB binding sites of to the muscarinic receptor.