Genetic population structure of the agaric Blastosporella zonata (Lyophyllaceae) reveals cryptic species and different roles for sexual and asexual spores in dispersal.

Blastosporella zonata is one of the few basidiomycete fungi that produce asexual spores (conidia) on the mushroom. The role of these conidia in the fungal lifecycle is not known. We tested whether conidia are being utilized in local dispersal by looking for signatures of clonality in 21 samples from three localities separated by about three kilometres in Murillo, Colombia. To identify clonally related individuals, we sequenced three polymorphic markers at two unlinked loci (nuclear rRNA: ITS and LSU, and TEFIα) for all collections plus three herbarium samples. We identified two sets of clonally related individuals growing closely together in one of the three localities, and only one pair shared between localities. In all three localities we observed multiple non-clonally related dikaryons showing that sexual reproduction is also important. Our results indicate that the conidia on the mushroom are primarily important for local dispersal. Unexpectedly, our results also indicate two reproductively isolated populations, possibly representing cryptic biological species. Citation: Van de Peppel LJJ, Baroni TJ, Franco-Molano AE, et al. 2022. Genetic population structure of the agaric Blastosporella zonata (Lyophyllacea) reveals cryptic species and different roles for sexual and asexual spores in dispersal. Persoonia 49: 195-200. https://doi.org/10.3767/persoonia.2022.49.06.

DNA barcoding survey of Trichoderma diversity in soil and litter of the Colombian lowland Amazonian rainforest reveals Trichoderma strigosellum sp. nov. and other species.

The diversity of Trichoderma (Hypocreales, Ascomycota) colonizing leaf litter as well as the rhizosphere of Garcinia macrophylla (Clusiaceae) was investigated in primary and secondary rain forests in Colombian Amazonia. DNA barcoding of 107 strains based on the internal transcribed spacers 1 and 2 (ITS1 and 2) of the ribosomal RNA gene cluster and the partial sequence of the translation elongation factor 1 alpha (tef1) gene revealed that the diversity of Trichoderma was dominated (71 %) by three common cosmopolitan species, namely Trichoderma harzianum sensu lato (41 %), Trichoderma spirale (17 %) and Trichoderma koningiopsis (13 %). Four ITS 1 and 2 phylotypes (13 strains) could not be identified with certainty. Multigene phylogenetic analysis and phenotype profiling of four strains with an ITS1 and 2 phylotype similar to Trichoderma strigosum revealed a new sister species of the latter that is described here as Trichoderma strigosellum sp. nov. Sequence similarity searches revealed that this species also occurs in soils of Malaysia and Cameroon, suggesting a pantropical distribution.

TCR binding differs for a bacterial superantigen (SEE) and a viral superantigen (Mtv-9).

Both superantigens (SAG) and many anti-TCR monoclonal antibodies (mAb) have specificity for the V beta region of the TCR encoded by TCRBV genes. For instance the bacterial SAG staphylococcal enterotoxin E (SEE), the retroviral SAG MTV-9 and the mAb OT145 each react with human T cells expressing BV6S7. This BV gene encodes two common alleles. We found that SEE and the mAb preferentially activate T cells expressing BV6S7*1 as opposed to BV6S7*2, but Mtv-9 activates T cells expressing either allele. Thus binding to the TCR differs between the two SAGs. A mutation in the TCR HVR-4 region of BV6S7*1 (G72E), where the two BV6S7 alleles differ, indicated that HVR-4 is a component of the binding site for SEE and for the mAb OT145. BV6S7*2 has a charged E72 which may result in electrostatic repulsion of SEE, as SEE contains a similarly acidic aspartic acid residue at a TCR interaction site (204D).

Long-term impact of subthalamic stimulation on cognitive function in patients with advanced Parkinson's disease. / Impacto de la estimulación subtalámica a largo plazo sobre la situación cognitiva de los pacientes con enfermedad de Parkinson avanzada.

OBJECTIVE: The aim of this study was to evaluate the effects of deep brain stimulation of the subthalamic nucleus (DBS-SN) on cognitive function in patients with Parkinson's disease (PD) 5 years after surgery. MATERIAL AND METHODS: We conducted a prospective study including 50 patients with PD who underwent DBS-SN (62.5% were men; mean age of 62.2±8.2 years; mean progression time of 14.1±6.3 years). All patients were assessed before the procedure and at one year after surgery; 40 patients were further followed up until the 5-year mark. Follow-up assessments included the following neuropsychological tests: Mini-Mental State Examination (MMSE), Mattis Dementia Rating Scale (MDRS), letter-number sequencing of the WAIS-III (WAIS-III-LN), clock-drawing test, Rey auditory verbal learning test (RAVLT), Benton Visual Retention Test (BVRT), Judgment of Line Orientation (JLO) test, FAS Phonemic Verbal Fluency Test, Stroop test, and the Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: Patients were found to score lower on the MMSE (-0.89%), clock-drawing test (-2.61%), MDRS (-1.72%), and especially phonemic (-13.28%) and sematic verbal fluency tests (-12.40%) at one year after surgery. Delayed recall on the RAVLT worsened one year after the procedure (-10.12%). At 5 years, impairment affected mainly verbal fluency; scores decreased an additional 16.10% and 16.60% in semantic and phonemic verbal fluency, respectively. Moderate decreases were observed in immediate recall (-16.87%), WAIS-III-LN (-16.67%), and JLO test (-11.56%). DISCUSSION: In our sample, DBS-SN did not result in global cognitive impairment 5 years after surgery. Verbal function was found to be significantly impaired one year after the procedure. Impaired learning and visuospatial function may be attributed to degeneration associated with PD.

Seguridad y eficiencia de sedación balanceada con propofol y remifentanil en endoscopia digestiva alta diagnóstica. Una experiencia exitosa / A Successful Experience: Safety and Efficiency of Balanced Sedation with Propofol and Remifentanil in Diagnostic Endoscopy

Resumen La sedación es una técnica anestésica de amplio uso en los procedimientos endoscópicos digestivos actuales dado su claro beneficio en la tolerancia y comodidad para el paciente y el endoscopista. El medicamento de mayor uso en la actualidad para utilizarse como monosedación es el propofol, pero los esquemas balanceados utilizando más de un medicamento ahora son ampliamente usados en endoscopia diagnóstica o terapéutica. La sedación balanceada utilizando propofol y remifentanilo permite la potenciación sinérgica de un sedante con un opioide de ultracorta acción, lo que a su vez favorece la disminución respectiva de cada dosis. Se presenta una serie de 1148 pacientes llevados a endoscopia digestiva alta diagnóstica con dosis promedio de remifentanilo de 0,9 µg/kg de peso y de propofol de 0,47 mg/kg de peso, sin eventos adversos graves, con excelente satisfacción para el endoscopista y con muy bajo costo de la dosis por medicamento, con lo que se infiere que es un esquema seguro y eficiente.

Abstract Sedation is an anesthetic technique that is widely used in current digestive endoscopic procedures because of its clear benefits for patients' tolerance and comfort and for the endoscopist. Propofol is the most commonly used drug in monosedation, but balanced regimens using more than one drug are now widely used in diagnostic and therapeutic endoscopy. Balanced sedation using Propofol and Remifentanil allows synergistic potentiation of a sedative with an ultra-short acting opioid which in turn favors decreases of each dose. This is a series of 1,148 patients who underwent diagnostic endoscopy under balanced sedation with average Remifentanil doses of 0.9 mcg/kg of body weight and average Propofol doses of 0.47 mg/kg of body weight. There were no serious adverse events, endoscopists were highly satisfied with the procedures, and costs per drug dose were very low. This is clearly a safe and efficient scheme.

Amatoxin and phallotoxin composition in species of the genus Amanita in Colombia: a taxonomic perspective.

Some species in the genus Amanita have a great variety of toxic secondary metabolites. They are characterized macroscopically by having a white spore print and free gills, and microscopically by the presence of a divergent hymenophoral trama. Some species of Amanita present in Colombia were chemically characterized by analyzing their toxin composition using HPLC. Samples were collected in oak (Quercus humboldtii) and pine (Pinus radiata) forests. Twelve species were recovered, Amanita fuligineodisca, Amanita xylinivolva, Amanita flavoconia, Amanita rubescens, Amanita bisporigera, Amanita muscaria, Amanita humboldtii, Amanita sororcula, Amanita brunneolocularis, Amanita colombiana, Amanita citrina, Amanita porphyria as well as two unreported species. Results showed that most of the analyzed species have α -amanitin in concentrations ranging from 50 ppm to 6000 ppm. Concentrations of α-amanitin in the pileus were significantly greater than in the stipe. Phalloidin and phallacidin were only present in A. bisporigera. Chromatographic profiles are proposed as an additional taxonomic tool since specific peaks with similar retention times were conserved at the species level.

Prevalence of neuropsychiatric symptoms in mild cognitive impairment and Alzheimer's disease, and its relationship with cognitive impairment.

OBJECTIVE: The study aimed to describe the prevalence of Neuropsychiatric symptoms (NPS) in Alzheimer's disease (AD), amnestic mild cognitive impairment (MCI) and controls using the 12-item Neuropsychiatric Inventory (NPI) and to analyze the relationships between neuropsychiatric symptoms with specific neuropsychological tests. PATIENTS AND METHODS: We prospectively studied 485 patients from the Memory Unit in Cruces Hospital (Spain), 344 met the criteria of NINCDS-ADRDA for probable AD (99 were classified as mild and 245 as moderate-severe), 91 for MCI and 50 were controls. Mini-mental State Examination (MMSE) and CDR (Clinical Dementia Rating) were used to evaluate global cognitive function and to classify the severity of cognitive impairment. The neuropsychological test battery included memory test, verbal fluency, visuoespatial skills and daily living scales. The 12-items Neuropsychiatric Inventory (NPI) version was used to assess neuropsychiatric symptoms. All patients underwent a neuroimaging study (CT scan and/or MRI). Patients were not treated with antidementia or psychotropic drugs. RESULTS: Apathy and depression were more prevalent NPS in moderate-severe AD (78.4% and 44.1%, respectively), mild AD (64.6% and 41.4%, respectively) and MCI (50.5% and 33%, respectively) patients than in controls (6% and 8%, respectively). The prevalence and the mean scores of all symptoms increased along the severity of the disease, except for sleep and appetite disorders. In patients with mild AD a relationship was found between the presence of NPS and RDRS-2 scale (p = 0.003); and between NPS and RDRS-2 (p = 0.029) and SS-IQCODE scales (p = 0.039) in moderate-severe patients. CONCLUSIONS: NPS were more prevalent in AD and MCI patients than in controls. In AD and MCI patients apathy and depression were the most prevalent NPS. The prevalence and the mean scores of all symptoms gradually increased along the severity of the disease, except for sleep and appetite disorders. We have no found a relationship between neuropsycological test and the presence of NPS, but in patients with mild and moderate-severe AD there is a relationship with daily living scales.

Cutting edge: the IgG response to the circumsporozoite protein is MHC class II-dependent and CD1d-independent: exploring the role of GPIs in NK T cell activation and antimalarial responses.

Biochemical analysis has suggested that self GPI anchors are the main natural ligand associated with mouse CD1d molecules. A recent study reported that Valpha14+ NK T cells responded to self as well as foreign (parasite-derived) GPIs in a CD1d-dependent manner. It further reported that the IgG response to the Plasmodium berghei malarial circumsporozoite (CS) protein was severely impaired in CD1d-deficient mice, leading to a model whereby NK T cells, upon recognition of CD1d molecules presenting the CS-derived GPI anchor, provide help for B cells secreting anti-CS Abs. We tested this model by comparing the anti-CS Ab responses of wild-type, CD1d-deficient, and MHC class II-deficient mice. We found that the IgG response to the CS protein was solely MHC class II-dependent. Furthermore, by measuring the response of a broad panel of CD1d-autoreactive T cells to GPI-deficient CD1d-expressing cells, we found that GPIs were not required for autoreactive responses.

In human malaria protective antibodies are directed mainly against the Lys-Glu ion pair within the Lys-Glu-Lys motif of the synthetic vaccine SPf 66.

The KEK (Lysine-Glutamic acid-Lysine) motif is frequently found in the primary structure of certain malaria proteins involved in invasion, and plays an important role in the interaction of these proteins with the erythrocyte. This motif is contained in a peptide which forms part of the polymeric synthetic malaria vaccine SPf 66, currently undergoing extensive human trials. Analysis of the antibody titres against the subunit peptides that comprise this vaccine has shown that protection is associated with high titres to the KEK-containing peptide. In this paper we examine the fine recognition of this motif by polyclonal sera from protected vaccinated individuals, demonstrating the critical role played by the interacting ion pair formed between the amino terminal lysine (K) and glutamic acid (E), which act as contact residues for an important proportion of the antibody population directed against this vaccine. This ion pair in the KEK motif constitutes perhaps one of the most important malaria epitopes involved in protection, and could explain the mechanism through which protective immunity is acquired.

Specific interactions of synthetic peptides derived from P. falciparum merozoite proteins with human red blood cells.

In the search for strategies which might help in the elucidation of molecular mechanisms involved in the red blood cell (RBC) invasion by P. falciparum merozoites, and with the specific aim of establishing whether synthetic peptides derived from selected parasite proteins bind to human RBCs, 26 different peptides were chemically synthesized and radiolabeled. It was found that the peptides could be grouped, according to their RBC-binding kinetics, into high, medium and low binding activity. A correlation was detected between the high binding activity of a peptide and the presence of either a KEK motif (or its variants LEK or KEL) or a NVXAA (where X is V or Y). Peptides with medium or low binding activities did not possess either of these two consensus sequences. Selective modification of amino acids within the KEK motif diminished their uptake or binding capacity. Competitive inhibition assays of labeled or unlabeled peptide demonstrated a correlation between the presence of KEK or NVXAA motifs and a high binding activity of a peptide. Invasion-inhibition studies showed a direct correlation between a peptide's binding activity and inhibitions of human RBC reinvasion. Other experiments showed that high binding activity peptides show a decreased uptake with related and nonrelated human erythrocytes.

CD4-independent in vivo priming of murine CTL by optimal MHC class I-restricted peptides derived from intracellular pathogens.

CTL combat intracellular pathogens by killing infected cells. The molecular targets of their attack are foreign peptides bound to self MHC encoded class I molecules. Immunization of mice with peptides containing CTL determinants was shown to elicit CD4-dependent CTL. Here, we have achieved in vivo CTL priming with naturally processed 8-10 amino acid long class I-restricted peptides emulsified in an adjuvant. A potent, reproducible and physiologically relevant response was obtained using peptides from an intracellular bacterium and five viruses (including HIV) in two murine MHC haplotypes. This method is suitable for multiple vaccination, since a 'cocktail' of peptides derived from three pathogens elicited effector CTL against each pathogen. Most importantly, peptide-induced CD8+CD4- CTL were CD4(+)-independent. These results have implications for CTL induction in situations where CD4 T cells are depleted or compromised, as is the case in HIV infection.

[Neuropsychological changes and bilateral subthalamic deep brain stimulation in Parkinson's disease]. / Efectos cognitivos de la estimulación cerebral profunda sobre el núcleo subtalámico en la enfermedad de Parkinson.

INTRODUCTION: To investigate neuropsychiatric changes in Parkinson's disease (PD) patients after 12 months of bilateral subthalamic deep brain stimulation (DBS-STN). SUBJECTS: Nine out of 23 patients with PD subjected to DBS-STN were included. The mean follow-up of this cohort was 12 months, mean disease duration 14.2 5.5 years and mean UPDRS motor score in <> 43.2 13.7. METHODS: Patients were selected on the basis of CAPSIT criteria. They underwent bilateral implant of stimulators in STN under stereotactic conditions. Quality of life scale (PDQ 39), depression scale (Brev-Cet), frontal function test (Stroop, Wisconsin, verbal fluency) and memory evaluation (Barcelona test) were monitored at baseline in <> medication and after 12 months in <> medication/<> stimulation. RESULTS: The patients' motor scores improved on an average of 40.2 % (p = 0.0002) in <> medication situation and 58 % in quality of life scores. We observed a benefit in depression scores (52 %, p = 0.003). Immediate verbal memory improved as well, 25 % (p = 0.04) in recall memory and 14 % (p = 0.02) in recognition memory. No changes were observed in visual memory, verbal fluency and/or global cognitive tests. CONCLUSION: DBS-STN in PD patients seems to be an effective tool for improving their quality of life, due to its benefits on motor function, verbal memory and mood. Bilateral DBS-STN did not affect either verbal fluency or executive functions in our patients. Neuropsychological assessment is a good tool for selection and study of the operated patients.

Mycobacterium tuberculosis lipomannan induces apoptosis and interleukin-12 production in macrophages.

The mycobacterial cell wall component lipoarabinomannan (LAM) has been described as a virulence factor of Mycobacterium tuberculosis, and modification of the terminal arabinan residues of this compound with mannose caps (producing mannosyl-capped LAM [ManLAM]) in M. tuberculosis or with phosphoinositol caps (producing phosphoinositol-capped LAM [PILAM]) in Mycobacterium smegmatis has been implicated in various functions associated with these lipoglycans. A structure-function analysis was performed by using LAMs and their biosynthetic precursor lipomannans (LMs) isolated from different mycobacterial species on the basis of their capacity to induce the production of interleukin-12 (IL-12) and/or apoptosis of macrophage cell lines. Independent of the mycobacterial species, ManLAMs did not induce IL-12 gene expression or apoptosis of macrophages, whereas PILAMs induced IL-12 secretion and apoptosis. Interestingly, uncapped LAM purified from Mycobacterium chelonae did not induce IL-12 secretion or apoptosis. Furthermore, LMs, independent of their mycobacterial origins, were potent inducers of IL-12 and apoptosis. The precursor of LM, phosphatidyl-myo-inositol dimannoside, had no activity, suggesting that the mannan core of LM was required for the activity of LM. The specific interaction of LM with Toll-like receptor 2 (TLR-2) but not with TLR-4 suggested that these responses were mediated via the TLR-2 signaling pathway. Our experiments revealed an important immunostimulatory activity of the biosynthetic LAM precursor LM. The ratio of LAM to LM in the cell wall of mycobacteria may be an important determinant of virulence, and enzymes that modify LM could provide targets for development of antituberculosis drugs and for derivation of attenuated strains of M. tuberculosis.

Peptide selection by an MHC H-2Kb class I molecule devoid of the central anchor ("C") pocket.

The peptide-binding site of the murine MHC class I molecule H-2Kb contains a deep C pocket, that is critical for peptide binding, as it accepts the anchor phenylalanine or tyrosine residue located in the middle (position 5, P5F/Y) of H-2Kb binding peptides. H-2Kb predominantly binds octameric peptides. By both criteria, H-2Kb is unique among the known murine and human class I molecules, none of which have a deep C pocket or preferentially select octamers. We investigated the relative importance of the C pocket in peptide selection and binding by the MHC. An MHC class I H-2Kb variant, Kbw9, predicted to contain no C pocket, was engineered by replacing valine at MHC9 with tryptophan. This mutation drastically altered the selection of peptides bound to Kbw9. The Kbw9 molecule predominantly, if not exclusively, bound nonamers. New peptide anchor residues substituted for the loss of the P5F/Y:C pocket interaction. P3P/Y, which plays an auxiliary role in binding to Kb, assumed the role of a primary anchor, and P5R was selected as a new primary anchor, most likely contacting the E pocket. These experiments demonstrate that the presence of a deep C pocket is responsible for the selection of octameric peptides as the preferred ligands for Kb and provide insight into the adaptation of peptides to a rearranged MHC groove.