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Photodissociation of the CH2Cl radical is investigated by using high-level multireference configuration interaction ab initio methods, including the spin–orbit coupling. All possible fragmentation pathways, namely, CH2Cl + hν → CH2 + Cl, HCCl + H, and CCl + H2, have been analyzed. The potential-energy curves of the ground and several excited electronic states along the corresponding dissociating bond distance of each pathway have been calculated. Inclusion of the spin–orbit couplings is found to be crucial because it strongly determines the shape of the curves of the different excited states and, therefore, their photodissociation dynamics behavior. Analysis of the potential curves indicates that the pathways producing CH2 + Cl and HCCl + H can occur through a fast direct dissociation mechanism, while the pathway leading to CCl + H2 involves much slower dissociation mechanisms such as internal conversion between electronic states, predissociation, or tunneling through exit barriers. The main implications are that the two faster channels are predicted to be dominant, while the slower pathway is expected to be very unlikely and rather irrelevant. Appreciable actinic fluxes of solar irradiation are available at stratospheric altitudes where ozone is abundant, in the wavelength range where absorption of the first low-lying excited states of CH2Cl has been observed experimentally. Our results show that in this excitation energy range, the above-mentioned two dominant dissociation pathways are open and then could contribute to stratospheric ozone depletion. [ABSTRACT FROM AUTHOR]

Porcine blood, a significant byproduct of the pork industry, represents a potential source of antimicrobial peptides (AMPs). AMPs offer a promising alternative to chemical antimicrobials, which can be used as natural preservatives in the food industry. AMPs can exhibit both antibacterial and/or antifungal properties, thus improving food safety and addressing the growing concern of antibiotic and antifungal resistance. The objective of this study was to evaluate the antimicrobial activity of potential AMPs previously identified from porcine cruor hydrolysates. To this end, a total of sixteen peptides were chemically synthesized and their antimicrobial activities (antibacterial, anti-mold, and anti-yeast) were evaluated using microtitration and agar well diffusion methods against a wide range of microorganisms. Five new peptide sequences demonstrated antifungal activity, with Pep5 (FQKVVAGVANALAHKYH), an alpha-helix peptide, exhibiting the most promising results. Pep5 demonstrated efficacy against nine of the eleven fungal isolates, exhibiting low minimum inhibitory concentrations (MICs) and a fungicidal effect against key spoilage fungi (Rhodotorula mucilaginosa, Debaryomyces hansenii, Candida guilliermondii, Paecilomyces spp., Eurotium rubrum, Mucor racemosus, Aspergillus versicolor, Penicillium commune, and P. chrysogenum). These findings illustrate the potential of porcine blood hydrolysates as a source of AMPs, particularly antifungal peptides, which are less known and less studied than the antibacterial ones. Among the tested sequences, Pep5 exhibited the most promising characteristics, including broad-spectrum activity, low MICs, and a fungicidal effect. It is, therefore, a promising candidate for further research and for potential applications in the porcine industry and beyond.

Acetaldehyde is a very relevant atmospheric species whose photodissociation has been extensively studied in the first absorption band both experimentally and theoretically. Very few works have been reported on acetaldehyde photodissociation at higher excitation energies. In this work, the photodissociation dynamics of acetaldehyde is investigated by means of high-level multireference configuration interaction ab initio calculations. Five different fragmentation pathways of acetaldehyde are explored by calculating the potential-energy curves of the ground and several excited electronic states along the corresponding dissociating bond distances. The excitation energy range covered in the study is up to 10 eV, nearly the ionization energy of acetaldehyde. We intend to rationalize the available experimental results and, in particular, to elucidate why some of the studied fragmentation pathways are experimentally observed in the different excitation energy regions and some others are not. Based on the shape of the calculated potential curves, we are able to explain the main findings of the available experiments, also suggesting possible dynamical dissociation mechanisms in the different energy regions. Thus, the reported potential curves are envisioned as a useful tool to interpret the currently available experiments as well as future ones on acetaldehyde photodissociation at excitation wavelengths in the range studied here. [ABSTRACT FROM AUTHOR]

Bromine atom (Br) reactions lead to ozone depletion in the troposphere and stratosphere. Photodegradation of bromocarbons is one of the main sources of bromine atoms in the atmosphere. Here, we use high-level ab initio methods, including spin–orbit effects, to study the photodissociation of the CH2Br radical. All possible fragmentation pathways, namely CH2Br + hν → CH2 + Br, HCBr + H, and CBr + H2, have been analyzed. Potential-energy curves of the ground and several excited electronic states along the corresponding dissociating bond distance of each pathway have been calculated. Considering the actinic fluxes of solar irradiation in the troposphere and in the stratosphere in the relevant range of frequencies, it is found that the first five excited states of CH2Br can be accessed from the ground state. Analysis of the potential curves shows that the pathways producing CH2 + Br and HCBr + H can proceed through a fast direct dissociation mechanism, while the pathway leading to CBr + H2 involves much slower dissociation mechanisms like internal conversion between electronic states, predissociation, or tunneling through exit barriers. The main implications are that the two faster channels are predicted to be dominant, and the slower pathway is expected to be less relevant. The tropospheric and stratospheric solar actinic fluxes also allow for further dissociation of the HCBr and CBr fragments, generating additional Br atoms, provided that they survive possible collisions with other atmospheric reagents. Finally, we discuss the possible effect of each of the three CH2Br dissociation pathways on the depletion of atmospheric ozone. [ABSTRACT FROM AUTHOR]

Porcine blood, a significant byproduct of the pork industry, represents a potential source of antimicrobial peptides (AMPs). AMPs offer a promising alternative to chemical antimicrobials, which can be used as natural preservatives in the food industry. AMPs can exhibit both antibacterial and/or antifungal properties, thus improving food safety and addressing the growing concern of antibiotic and antifungal resistance. The objective of this study was to evaluate the antimicrobial activity of potential AMPs previously identified from porcine cruor hydrolysates. To this end, a total of sixteen peptides were chemically synthesized and their antimicrobial activities (antibacterial, anti-mold, and anti-yeast) were evaluated using microtitration and agar well diffusion methods against a wide range of microorganisms. Five new peptide sequences demonstrated antifungal activity, with Pep5 (FQKVVAGVANALAHKYH), an alpha-helix peptide, exhibiting the most promising results. Pep5 demonstrated efficacy against nine of the eleven fungal isolates, exhibiting low minimum inhibitory concentrations (MICs) and a fungicidal effect against key spoilage fungi (Rhodotorula mucilaginosa, Debaryomyces hansenii, Candida guilliermondii, Paecilomyces spp., Eurotium rubrum, Mucor racemosus, Aspergillus versicolor, Penicillium commune, and P. chrysogenum). These findings illustrate the potential of porcine blood hydrolysates as a source of AMPs, particularly antifungal peptides, which are less known and less studied than the antibacterial ones. Among the tested sequences, Pep5 exhibited the most promising characteristics, including broad-spectrum activity, low MICs, and a fungicidal effect. It is, therefore, a promising candidate for further research and for potential applications in the porcine industry and beyond. [ABSTRACT FROM AUTHOR]

A collection of 259 staphylococci of 13 different species [212 coagulase-negative (CoNS) and 47 coagulase-positive (CoPS)] recovered from nasotracheal samples of 87 healthy nestling white storks was tested by the spot-on-lawn method for antimicrobial-activity (AA) against 14 indicator bacteria. Moreover, extracts of AP isolates were obtained [cell-free-supernatants (CFS) both crude and concentrated and butanol extracts] and tested against the 14 indicator bacteria. The microbiota modulation capacity of AP isolates was tested considering: (a) intra-sample AA, against all Gram-positive bacteria recovered in the same stork nasotracheal sample; (b) inter-sample AA against a selection of representative Gram-positive bacteria of the nasotracheal microbiota of all the storks (30 isolates of 29 different species and nine genera). In addition, enzymatic susceptibility test was carried out in selected AP isolates and bacteriocin encoding genes was studied by PCR/sequencing. In this respect, nine isolates (3.5%; seven CoNS and two CoPS) showed AA against at least one indicator bacteria and were considered antimicrobial-producing (AP) isolates. The AP isolates showed AA only for Gram-positive bacteria. Three of these AP isolates (S. hominis X3764, S. sciuri X4000, and S. chromogenes X4620) revealed AA on all extract conditions; other four AP isolates only showed activity in extracts after concentration; the remaining two AP isolates did not show AA in any of extract conditions. As for the microbiota modulation evaluation, three of the nine AP-isolates revealed intra-sample AA. It is to highlight the potent inter-sample AA of the X3764 isolate inhibiting 73% of the 29 representative Gram-positive species of the nasotracheal stork microbiota population. On the other hand, enzymatic analysis carried out in the two highest AP isolates (X3764 and X4000) verified the proteinaceous nature of the antimicrobial compound and PCR analysis revealed the presence of lantibiotic-like encoding genes in the nine AP isolates. In conclusion, these results show that nasotracheal staphylococci of healthy storks, and especially CoNS, produce antimicrobial substances that could be important in the modulations of their nasal microbiota.

Necrotic enteritis (NE) caused by C. perfringens is one of the most common diseases of poultry and results in a huge economic loss to the poultry industry, with resistant clostridial strains being a serious concern and making the treatment difficult. Whole-genome sequencing approaches represent a good tool to determine resistance profiles and also shed light for a better understanding of the pathogen. The aim of this study was to characterize, at the genomic level, a collection of 20 C. perfringens isolates from poultry affected by NE, giving special emphasis to resistance mechanisms and production of bacteriocins. Antimicrobial resistance genes were found, with the tet genes (associated with tetracycline resistance) being the most prevalent. Interestingly, two isolates carried the erm(T) gene associated with erythromycin resistance, which has only been reported in other Gram-positive bacteria. Twelve of the isolates were toxinotyped as type A and seven as type G. Other virulence factors encoding hyaluronases and sialidases were frequently detected, as well as different plasmids. Sequence types (ST) revealed a high variability of the isolates, finding new allelic combinations. Among the isolates, C. perfringens MLG7307 showed unique characteristics; it presented a toxin combination that made it impossible to toxinotype, and, despite being identified as C. perfringens, it lacked the housekeeping gene colA. Genes encoding bacteriocin BCN5 were found in five isolates even though no antimicrobial activity could be detected in those isolates. The bcn5 gene of three of our isolates was similar to one previously reported, showing two polymorphisms. Concluding, this study provides insights into the genomic characteristics of C. perfringens and a better understanding of this avian pathogen.

The photodecomposition of methanimine (CH _2 NH) in the interstellar medium through several possible pathways is investigated by means of high-level multireference configuration interaction ab initio calculations. Among these pathways are photodissociation pathways involving hydrogen-atom elimination from both the CH _2 and NH groups, and fragmentation into CH _2 and NH. Potential-energy curves for the ground and several excited electronic states, as well as nonadiabatic couplings between them, are calculated. Possible dissociation mechanisms are discussed for the different pathways. It is found that the minimum excitation energy required for methanimine dissociation is above 7 eV. By using a two-dimensional representation of methanimine, CH _2 NH → CHNH _2 isomerization is explored as an additional methanimine decomposition pathway. Hydrogen-atom elimination from the CH _2 group is also investigated along the isomerization pathway. The results show that the isomerization proceeds by overcoming a transition state that in the first two excited states would require excitation energies similar to or somewhat lower than the typical minimum energies needed for breaking the molecule through the fragmentation pathways. Therefore, CH _2 NH → CHNH _2 isomerization can effectively contribute to methanimine decomposition, competing efficiently with the photodissociation pathways. The radiation content present in the interstellar medium makes possible the occurrence of all the pathways studied.

Necrotic enteritis (NE), caused by Clostridium perfringens, is an emerging issue in poultry farming. New approaches, other than antibiotics, are necessary to prevent NE development and the emergence of multidrug-resistant bacteria. Enterococci are commensal microorganisms that can produce enterocins, antimicrobial peptides with activities against pathogens, and could be excellent candidates for protective cultures. This study aimed to screen and characterize Enterococcus strains of poultry origin for their inhibitory activity against C. perfringens. In total, 251 Enterococcus strains of poultry origin plus five bacteriocin-producing (BP+) E. durans strains of other origins were screened for antimicrobial activity against the indicator C. perfringens X2967 strain using the “spot on the lawn” method. We detected thirty-two BP+ strains (eleven Enterococcus faecium, nine E. gallinarum, eight E. faecalis, three E. durans, and one E. casseliflavus). We further studied the antimicrobial activity of the supernatants of these 32 BP+ strains using agar well diffusion and microtitration against a collection of 20 C. perfringens strains. Twelve BP+ enterococci that were found to exhibit antimicrobial activity against C. perfringens were characterized using whole genome sequencing. Among these, E. faecium X2893 and X2906 were the most promising candidates for further studies as protective cultures for poultry farming. Both strains belong to the sequence type ST722, harbor the genes encoding for enterocin A and enterocin B, do not possess acquired resistance genes, do not carry plasmids, and present the acm gene, which is implicated in host colonization. Further research is needed to determine the utility of these strains as protective cultures.

Multidrug-resistant Clostridium perfringens infections are a major threat to the poultry industry. Effective alternatives to antibiotics are urgently needed to prevent these infections and limit the spread of multidrug-resistant bacteria. The aim of the study was to produce by chemical synthesis a set of enterocins of different subgroups of class II bacteriocins and to compare their spectrum of inhibitory activity, either alone or in combination, against a panel of twenty C. perfringens isolates. Enterocins A, P, SEK4 (class IIa bacteriocins), B (unsubgrouped class II bacteriocin), and L50 (class IId leaderless bacteriocin) were produced by microwave-assisted solid-phase peptide synthesis. Their antimicrobial activity was determined by agar well diffusion and microtitration methods against twenty C. perfringens isolates and against other pathogens. The FICINDEX of different combinations of the selected enterocins was calculated in order to identify combinations with synergistic effects. The results showed that synthetic analogs of L50A and L50B were the most active against C. perfringens. These peptides also showed the broadest spectrum of activity when tested against other non-clostridial indicator strains, including Listeria monocytogenes, methicillin-resistant Staphylococcus aureus, Streptococcus suis, Streptococcus pyogenes, Enterococcus cecorum, Enterococcus faecalis, as well as Gram-negative bacteria (Campylobacter coli and Pseudomonas aeruginosa), among others. The selected synthetic enterocins were combined on the basis of their different mechanisms of action, and all combinations tested showed synergy or partial synergy against C. perfringens. In conclusion, because of their high activity against C. perfringens and other pathogens, the use of synthetic enterocins alone or as a consortium can be a good alternative to the use of antibiotics in the poultry sector. [ABSTRACT FROM AUTHOR]

Aim The poultry industry represents an important economic sector in Tunisia. This study aims to determine the antimicrobial resistance phenotypes and genotypes and virulence factors of enterococci collected from chicken caecum in Tunisia. Methods and results Forty-nine composite chicken caecum samples were recovered in 49 different Tunisian farms (December 2019–March 2020). Each composite sample corresponds to six individual caecum from each farm. Composite samples were plated on Slanetz–Bartley agar both supplemented (SB-Van) and not supplemented (SB) with vancomycin and isolates were identified by matrix-assisted laser desorption/ionization time-of-flight. Antibiotic resistance and virulence genes were tested by Polymerase Chain Reaction (PCR) and sequencing and multilocus-sequence-typing of selected enterococci was performed. One hundred sixty seven enterococci of six different species were recovered. Acquired linezolid resistance was detected in 6 enterococci of 4/49 samples (8.1%): (A) four optr A-carrying Enterococcus faecalis isolates assigned to ST792, ST478, and ST968 lineages; (B) two poxt A-carrying Enterococcus faecium assigned to ST2315 and new ST2330. Plasmid typing highlighted the presence of the rep 10, rep 14, rep 7, rep 8, and pLG1 in these strains. One vancomycin-resistant E. faecium isolate (typed as ST1091) with van A gene (included in Tn 1546) was detected in SB-Van plates. The gelE, agg, esp , and hyl virulence genes were found in linezolid- and vancomycin-resistant enterococci. High resistance rates were identified in the enterococci recovered in SB plates: tetracycline [74.8%, tet (M) and tet (L) genes], erythromycin [65.9%, erm (B)], and gentamicin [37.1%, aac(6′)-Ie–aph(2″)-Ia ]. Conclusion The detection of emerging mechanisms of resistance related to linezolid and vancomycin in the fecal enterococci of poultry farms has public health implications, and further surveillance should be carried out to control their dissemination by the food chain. [ABSTRACT FROM AUTHOR]

It has been postulated that monitoring measurable residual disease (MRD) could be used as a surrogate marker of progression-free survival (PFS) in chronic lymphocytic leukemia (CLL) patients after treatment with immunochemotherapy regimens. In this study, we analyzed the outcome of 84 patients at 3 years of follow-up after first-line treatment with fludarabine, cyclophosphamide and rituximab (FCR) induction followed by 36 months of rituximab maintenance thearpy. MRD was assessed by a quantitative four-color flow cytometry panel with a sensitivity level of 10−4. Eighty out of 84 evaluable patients (95.2%) achieved at least a partial response or better at the end of induction. After clinical evaluation, 74 patients went into rituximab maintenance and the primary endpoint was assessed in the final analysis at 3 years of follow-up. Bone marrow (BM) MRD analysis was performed after the last planned induction course and every 6 months in cases with detectable residual disease during the 36 months of maintenance therapy. Thirty-seven patients (44%) did not have detectable residual disease in the BM prior to maintenance therapy. Interestingly, 29 patients with detectable residual disease in the BM after induction no longer had detectable disease in the BM following maintenance therapy. After a median followup of 6.30 years, the median overall survival (OS) and PFS had not been reached in patients with either undetectable or detectable residual disease in the BM, who had achieved a complete response at the time of starting maintenance therapy. Interestingly, univariate analysis showed that after rituximab maintenance OS was not affected by IGHV status (mutated vs. unmutated OS: 85.7% alive at 7.2 years vs. 79.6% alive at 7.3 years, respectively). As per protocol, 15 patients (17.8%), who achieved a complete response and undetectable peripheral blood and BM residual disease after four courses of induction, were allowed to stop fludarabine and cyclophosphamide and complete two additional courses of rituximab and continue with maintenance therapy for 18 cycles. Surprisingly, the outcome in this population was similar to that observed in patients who received the full six cycles of the induction regimen. These data show that, compared to historic controls, patients treated with FCR followed by rituximab maintenance have high-quality responses with fewer relapses and improved OS. The tolerability of this regime is favorable. Furthermore, attaining an early undetectable residual disease status could shorten the duration of chemoimmunotherapy, reducing toxicities and preventing long-term side effects. The analysis of BM MRD after fludarabine-based induction could be a powerful predictor of post-maintenance outcomes in patients with CLL undergoing rituximab maintenance and could be a valuable tool to identify patients at high risk of relapse, influencing further treatment strategies. This trial is registered with EudraCT n. 2007-002733-36 and ClinicalTrials.gov Identifier: NCT00545714.

The role of the air as a vehicle of bacteria dissemination in the farming environment has been previously reported, but still scarcely studied. This study investigated the bacteria density/diversity of the inside and outside air and of litter samples at a broiler farm. Samples were collected considering two seasons, three outside air distances (50/100/150 m) and the four cardinal directions. Selective media was used for staphylococci, enterococci, and Enterobacteriaceae recovery. A high number of bacteria was detected in the litter (2.9 × 105–5.8 × 107 cfu/g) and in the inside air (>105 cfu/m3), but a low emission of bacteria was evidenced in the outside air (3). Moreover, the bacteria detected in the farm’s outside air decreased the further from the farm the sample was taken. A total of 544 isolates were identified by MALDI-TOF (146 from the litter, 142 from inside air and 256 from outside air). From these, 162 staphylococci (14 species; S. saprophyticus 40.7%), 176 Enterobacteriaceae (4 species; E. coli 66%) and 190 enterococci (4 species; E. hirae 83%) were detected. E. hirae was the predominant species, and identical PFGE clones were detected in inside and outside samples. The detection of identical DNA profiles in E. hirae isolates from inside and outside samples suggests the role of the air in bacterial dissemination from the inside of the broiler farm to the immediate environment.

Photodissociation of the CH2I radical and the CH2I+ cation is studied by means of high-level ab initio calculations, including spin–orbit effects. Potential-energy curves (PEC) along the dissociating bond distances involved in some fragmentation pathways of these species are computed for the ground and several excited electronic states. Based on the PECs obtained, the possible photodissociation mechanisms are analyzed and suggested. Significant differences are found between the fragmentation dynamics of the neutral radical and that of the cation. While a relatively simple dissociation dynamics is predicted for CH2I, more complex fragmentation mechanisms involving internal conversion and couplings between different excited electronic states are expected for CH2I+. The species studied here are relevant to atmospheric chemistry, and the present work can help to understand better how their photodissociation may affect chemical processes in the atmosphere. [ABSTRACT FROM AUTHOR]

Necrotic enteritis (NE) caused by C. perfringens is one of the most common diseases of poultry and results in a huge economic loss to the poultry industry, with resistant clostridial strains being a serious concern and making the treatment difficult. Whole-genome sequencing approaches represent a good tool to determine resistance profiles and also shed light for a better understanding of the pathogen. The aim of this study was to characterize, at the genomic level, a collection of 20 C. perfringens isolates from poultry affected by NE, giving special emphasis to resistance mechanisms and production of bacteriocins. Antimicrobial resistance genes were found, with the tet genes (associated with tetracycline resistance) being the most prevalent. Interestingly, two isolates carried the erm(T) gene associated with erythromycin resistance, which has only been reported in other Gram-positive bacteria. Twelve of the isolates were toxinotyped as type A and seven as type G. Other virulence factors encoding hyaluronases and sialidases were frequently detected, as well as different plasmids. Sequence types (ST) revealed a high variability of the isolates, finding new allelic combinations. Among the isolates, C. perfringens MLG7307 showed unique characteristics; it presented a toxin combination that made it impossible to toxinotype, and, despite being identified as C. perfringens, it lacked the housekeeping gene colA. Genes encoding bacteriocin BCN5 were found in five isolates even though no antimicrobial activity could be detected in those isolates. The bcn5 gene of three of our isolates was similar to one previously reported, showing two polymorphisms. Concluding, this study provides insights into the genomic characteristics of C. perfringens and a better understanding of this avian pathogen. [ABSTRACT FROM AUTHOR]

Chronic lymphocytic leukemia (CLL) is an incurable lymphoproliferative disorder with a heterogeneous genetic and clinical course. Two kinase inhibitors, ibrutinib and idelalisib, have demonstrated achievement of complete and durable remissions in relapse/refractory genetically unselected CLL patients. We present a case of relapsed CLL with extensive disease and hourglass deformity of urinary bladder as a result of the compression of two extraperitoneal paravesical soft tissue bulky masses, with excellent response to sequential kinase inhibitor therapy.

Clocking of electronically and vibrationally state-resolved channels of the fast photodissociation of CH3I in the A-band is re-examined in a combined experimental and theoretical study. Experimentally, a femtosecond pump-probe scheme is employed in the modality of resonant probing by resonance enhanced multiphoton ionization (REMPI) of the methyl fragment in different vibrational states and detection through fragment velocity map ion (VMI) imaging as a function of the time delay. We revisit excitation to the center of the A-band at 268 nm and report new results for excitation to the blue of the band center at 243 nm. Theoretically, two approaches have been employed to shed light into the observations: first, a reduced dimensionality 4D nonadiabatic wavepacket calculation using the potential energy surfaces by Xie et al. [J. Phys. Chem. A 104, 1009 (2000)]; and second, a full dimension 9D trajectory surface-hopping calculation on the same potential energy surfaces, including the quantization of vibrational states of the methyl product. In addition, high level ab initio electronic structure calculations have been carried out to describe the CH3 3pz Rydberg state involved in the (2 + 1) REMPI probing process, as a function of the carbon-iodine (C–I) distance. A general qualitative agreement is obtained between experiment and theory, but the effect of methyl vibrational excitation in the umbrella mode on the clocking times is not well reproduced. The theoretical results reveal that no significant effect on the state-resolved appearance times is exerted by the nonadiabatic crossing through the conical intersection present in the first absorption band. The vibrationally state resolved clocking times observed experimentally can be rationalized when the (2 + 1) REMPI probing process is considered. None of the other probing methods applied thus far, i.e., multiphoton ionization photoelectron spectroscopy, soft X-ray inner-shell photoelectron spectroscopy, VUV single-photon ionization, and XUV core-to-valence transient absorption spectroscopy, have been able to provide quantum state-resolved (vibrational) clocking times. More experiments would be needed to disentangle the fine details in the clocking times and dissociation dynamics arising from the detection of specific quantum-states of the molecular fragments. [ABSTRACT FROM AUTHOR]

Introducción: la pancreatitis autoinmune es un tipo de pancreatitis crónica caracterizado por un infiltrado linfoplasmocitario y una elevación de IgG e IgG4, que se ha descrito asociada a diversas manifestaciones extrapancreáticas y enfermedades autoinmunes, lo cual apoya la teoría de un mecanismo autoinmune fisiopatólogico de base. Caso clínico: presentamos el caso de un varón que debutó simultáneamente con una pancreatitis autoinmune asociada a fibrosis retroperitoneal y lesión de la vía biliar extrapancreática, con respuesta total tras tratamiento con corticoides durante 4 meses y ausencia de recurrencia tras 24 meses de seguimiento. Discusión: la pancreatitis autoinmune es un tipo de pancreatitis crónica que probablemente forme parte de un proceso sistémico autoinmune, cuyas manifestaciones extrapancreáticas más frecuentes son la fibrosis retroperitoneal y las lesiones de la vía biliar extrapancreática. Su correcto diagnóstico e inicio precoz del tratamiento puede favorecer la resolución completa de las lesiones, principalmente en los casos de bajo grado de actividad, con menor probabilidad de recurrencia.Introduction: autoimmune pancreatitis is a kind of chronic pancreatitis characterized by the presence of lymphoplasmacytic infiltration and severely elevated serum IgG and IgG4, which has been associated to many extrapancreatic lesions and other autoimmune disorders, leading to the theory of an autoimmune mechanism involved in the pathogenesis of this disease. Case report: we report the case of a man who simultaneously presented with autoimmune pancreatitis associated with retroperitonal fibrosis, and a lesion of the extrapancreatic bile duct, with total response to corticosteroid treatment for 4 moths and absence of recurrence after 24 months of follow-up. Discussion: autoimmune pancreatitis is a kind of chronic pancreatitis that is probably a part of a systemic autoinmune disease, with retroperitoneal fibrosis and extrapancreatic bile duct lesion being the most commonly associated extrapancreatic lesions. A correct diagnosis and early treatment of this disease may aid in the total resolution of lesions, especially in cases with a low activity grade.

Objetivo: este estudio ha tenido un doble objetivo: por un lado, evaluar el efecto del tratamiento erradicador para Helicobacter pylori en la respuesta sintomática de pacientes diagnosticados de dispepsia funcional y, por otro, determinar si los hallazgos histológicos podían servir como predictor de la efectividad de la terapia. En particular, se trató de averiguar si la presencia de gastritis antral (la que se asocia a la enfermedad ulcerosa péptica) podría predecir una mayor respuesta sintomática al tratamiento erradicador en los pacientes con dispepsia funcional e infección por Helicobacter pylori. Pacientes y métodos: estudio prospectivo, monocéntrico y aleatorizado, que incluyó a 48 pacientes con dispepsia funcional e infección por Helicobacter pylori (27 mujeres y 21 hombres, con edad media de 37 ± 13,5 años). Veintisiete pacientes recibieron el tratamiento erradicador (rabeprazol, claritromicina y amoxicilina durante 10 días, seguido de 20 mg/día de rabeprazol 3 meses) y 21 el tratamiento control (20 mg/día de rabeprazol 3 meses). Los pacientes fueron seguidos durante un año. Todos rellenaron el Cuestionario de calidad de vida asociada a dispepsia, que evalúa cuatro apartados: intensidad de los síntomas habituales, intensidad del dolor de estómago, incapacidad debida al dolor y satisfacción con la salud. Resultados: existió una mejoría significativa (p < 0,002) en los síntomas de los pacientes, tanto a los 6 como a los 12 meses tras el inicio del tratamiento, que además fue común a las dos pautas de tratamiento. En el análisis de regresión lineal múltiple, los efectos del tratamiento erradicador y de tener una sintomatología menos intensa antes de recibir el tratamiento, fueron los dos únicos factores independientes de forma significativa. La respuesta al tratamiento erradicador a los 6 meses fue significativamente mayor que con el tratamiento control (p = 0,01) en los pacientes con gastritis de predominio antral y en el apartado concreto de los síntomas habituales. Conclusiones: ambos tratamientos producen una mejoría sintomática significativa en los pacientes con dispepsia funcional. Se observa una tendencia hacia un beneficio sintomático mayor con el tratamiento erradicador respecto al control en pacientes con dispepsia funcional y en un medio con elevada prevalencia de infección por Helicobacter pylori. Existe una tendencia hacia la mejoría sintomática con el tratamiento erradicador en los pacientes que tienen una gastritis de predominio antral.Objective: this study evaluated Helicobacter pylori eradication therapy in terms of symptomatic response in patients with functional dyspepsia. On the other hand, we analyzed the importance of histologic findings as a predictor of treatment response. In particular, we studied whether antral gastritis (which is associated with peptic ulcer) may predict a greater symptomatic response to Helicobacter pylori eradication in functional dyspepsia. Patients and methods: this prospective, randomized, single-center trial included 48 patients with functional dyspepsia and Helicobacter pylori infection (27 women and 21 men, mean age 37 ± 13.5 years). Twenty-seven patients received a 10-day course of rabeprazole, amoxicillin, and clarithromycin (eradication group), followed by 20 mg of rabeprazole for 3 months. Twenty-one patients received 20 mg of rabeprazole for 3 months (control group). Patients were followed up over a 1-year period. All patients completed the Dyspepsia-Related Health Scale Questionnaire, which studies four dimensions: pain intensity, pain disability, non-pain symptoms, and satisfaction with dyspepsia-related health. Results: there was significant symptomatic improvement (p < 0.002) after 6 and 12 months, which was similar with both treatments. In the multivariate analyses, eradication therapy and less severe symptoms before treatment were the only independent factors. The symptomatic response to Helicobacter pylori eradication after 6 months was significantly greater as compared to control therapy (p = 0.01) in patients with antral gastritis and in the non-pain symptoms dimension of the questionnaire. Conclusions: both treatments proved to be clinically beneficial in patients with functional dyspepsia. We observed a tendency to greater symptomatic benefit with Helicobacter pylori eradication therapy when compared to control treatment in patients with functional dyspepsia and in a population with a high prevalence of his infection. There is a tendency to symptomatic benefit with Helicobacter pylori eradication therapy in patients with antral gastritis.

Objetivo: el objetivo de nuestro estudio fue valorar la utilidad de la ecoendoscopia en el estudio de la vía biliar extrahepática en los pacientes diagnosticados de pancreatitis aguda biliar y determinar los factores clínicos y analíticos relacionados con el resultado de la técnica. Material y métodos: se incluyeron en el estudio de modo consecutivo 73 pacientes (31 varones, 42 mujeres; media de edad 64 ± 15 años) con pancreatitis aguda biliar remitidos a nuestro servicio para la realización de ecoendoscopia biliopancreática. En todos los pacientes se realizó la técnica seguida de CPRE con esfinterotomía y técnica endoscópica para la extracción de cálculos cuando se identificó por ecoendoscopia la existencia de coledocolitiasis. Se compararon las características clínico-evolutivas de estos pacientes con respecto al resultado obtenido con la ecoendoscopia. Resultados: la media de tiempo transcurrido desde el ingreso hasta la realización de la ecoendoscopia fue de 7 ± 6 días. En 18 pacientes (24%) se observó en la ecoendoscopia la existencia de coledocolitiasis y en 17 de ellos se realizó esfinterotomía endoscópica. La presencia de coledocolitiasis fue más frecuente en aquellos pacientes con dilatación de la vía biliar extrahepática (55 vs. 14%; p < 0,05) y en aquellos con bilirrubina sérica superior a 3 mg/dl (41 vs. 18%; p < 0,05). Trece pacientes (18%) presentaron pancreatitis aguda severa. Catorce (19%) presentaron alguna complicación en relación con la pancreatitis aguda y un paciente murió. Se observó una complicación relacionada con la esfinterotomía endoscópica. Cuatro pacientes presentaron un nuevo episodio de pancreatitis aguda. No se observaron diferencias significativas en el porcentaje de complicaciones en los pacientes tratados de modo conservador respecto a aquellos con coledocolitiasis tratados con esfinterotomía endoscópica (18 vs. 22%; p > 0,05). Tampoco se observó esta diferencia en el subgrupo de pacientes con pancreatitis aguda severa (45 vs. 55%; p > 0,05). Conclusiones: la ecoendoscopia es una técnica útil en la selección de los pacientes con pancreatitis aguda biliar que se beneficiarán de la realización de una esfinterotomía endoscópica.Objective: the objective of our study was to evaluate the usefulness of endoscopic ultrasonography (EUS) for the study of the common bile duct in patients diagnosed with acute biliary pancreatitis, and to establish clinical and laboratory factors related to this technique. Materials and methods: seventy-three consecutive patients with acute biliary pancreatitis were included in the study (31 males and 42 females with a mean age of 64 ± 15) who were admitted to our department for biliopancreatic EUS. In all patients the technique was followed by ERCP with sphincterotomy, and endoscopy to remove stones when endoscopy revealed choledocholithiasis. Results: mean time from admission to echoendoscopy was 7 ± 6 days. In 18 patients (24%) the presence of choledocholithiasis was revealed by EUS, and in 17 a sphincterotomy was performed. Choledocholithiasis was more frequent in patients with common bile duct dilation (55 vs. 14%; p < 0.05). Thirteen patients (18%) showed severe acute pancreatitis. Fourteen (19%) showed complications related to acute pancreatitis, and one patient died. Four patients had a new episode of acute pancreatitis. No significant difference was seen in the percentage of complications between patients treated conservatively and patients with choledocholithiasis treated with endoscopic sphincterotomy (18 vs. 22%; p > 0.05). No difference was also detected for the subgroup of patients with severe acute pancreatitis (45 vs. 55%; p > 0.05). Conclusions: EUS is a useful technique for the selection of patients with acute biliary pancreatitis who may benefit from endoscopic sphincterotomy.

The site-specific hydrogen-atom elimination mechanism previously reported for photoexcited ethyl radicals (CH3CH2) [D. V. Chicharro et al., Chem. Sci., 2019, 10, 6494] is interrogated in the photodissociation of the ethyl isotopologues CD3CD2, CH3CD2 and CD3CH2 through the velocity map imaging (VMI) detection of the produced hydrogen- and deuterium-atoms. The radicals, generated in situ from photolysis of a precursor using the same laser pulse employed in their excitation to Rydberg states, decompose along the Cα-H/D and Cβ-H/D reaction coordinates through coexisting statistical and site-specific mechanisms. The experiments are carried out at two excitation wavelengths, 201 and 193 nm. The comparison between both sets of results provides accurate information regarding the primary role in the site-specific mechanism of the radical internal reservoir. Importantly, at 193 nm excitation, higher energy dissociation channels (not observed at 201 nm) producing low-recoil H/D-atoms become accessible. High-level ab initio calculations of potential energy curves and the corresponding non-adiabatic interactions allow us to rationalize the experimental results in terms of competitive non-adiabatic decomposition paths. Finally, the adiabatic behavior of the conical intersections in the face of several vibrational modes – the so-called vibrational promoting modes – is discussed. [ABSTRACT FROM AUTHOR]

A collection of 259 staphylococci of 13 different species [212 coagulase-negative (CoNS) and 47 coagulase-positive (CoPS)] recovered from nasotracheal samples of 87 healthy nestling white storks was tested by the spot-on-lawn method for antimicrobial-activity (AA) against 14 indicator bacteria. Moreover, extracts of AP isolates were obtained [cell-free-supernatants (CFS) both crude and concentrated and butanol extracts] and tested against the 14 indicator bacteria. The microbiota modulation capacity of AP isolates was tested considering: (a) intra-sample AA, against all Gram-positive bacteria recovered in the same stork nasotracheal sample; (b) inter-sample AA against a selection of representative Gram-positive bacteria of the nasotracheal microbiota of all the storks (30 isolates of 29 different species and nine genera). In addition, enzymatic susceptibility test was carried out in selected AP isolates and bacteriocin encoding genes was studied by PCR/sequencing. In this respect, nine isolates (3.5%; seven CoNS and two CoPS) showed AA against at least one indicator bacteria and were considered antimicrobial-producing (AP) isolates. The AP isolates showed AA only for Gram-positive bacteria. Three of these AP isolates (S. hominis X3764, S. sciuri X4000, and S. chromogenes X4620) revealed AA on all extract conditions; other four AP isolates only showed activity in extracts after concentration; the remaining two AP isolates did not show AA in any of extract conditions. As for the microbiota modulation evaluation, three of the nine AP-isolates revealed intra-sample AA. It is to highlight the potent inter-sample AA of the X3764 isolate inhibiting 73% of the 29 representative Gram-positive species of the nasotracheal stork microbiota population. On the other hand, enzymatic analysis carried out in the two highest AP isolates (X3764 and X4000) verified the proteinaceous nature of the antimicrobial compound and PCR analysis revealed the presence of lantibiotic-like encoding genes in the nine AP isolates. In conclusion, these results show that nasotracheal staphylococci of healthy storks, and especially CoNS, produce antimicrobial substances that could be important in the modulations of their nasal microbiota. [ABSTRACT FROM AUTHOR]

Necrotic enteritis (NE), caused by Clostridium perfringens, is an emerging issue in poultry farming. New approaches, other than antibiotics, are necessary to prevent NE development and the emergence of multidrug-resistant bacteria. Enterococci are commensal microorganisms that can produce enterocins, antimicrobial peptides with activities against pathogens, and could be excellent candidates for protective cultures. This study aimed to screen and characterize Enterococcus strains of poultry origin for their inhibitory activity against C. perfringens. In total, 251 Enterococcus strains of poultry origin plus five bacteriocin-producing (BP+) E. durans strains of other origins were screened for antimicrobial activity against the indicator C. perfringens X2967 strain using the "spot on the lawn" method. We detected thirty-two BP+ strains (eleven Enterococcus faecium, nine E. gallinarum, eight E. faecalis, three E. durans, and one E. casseliflavus). We further studied the antimicrobial activity of the supernatants of these 32 BP+ strains using agar well diffusion and microtitration against a collection of 20 C. perfringens strains. Twelve BP+ enterococci that were found to exhibit antimicrobial activity against C. perfringens were characterized using whole genome sequencing. Among these, E. faecium X2893 and X2906 were the most promising candidates for further studies as protective cultures for poultry farming. Both strains belong to the sequence type ST722, harbor the genes encoding for enterocin A and enterocin B, do not possess acquired resistance genes, do not carry plasmids, and present the acm gene, which is implicated in host colonization. Further research is needed to determine the utility of these strains as protective cultures. [ABSTRACT FROM AUTHOR]

To date over 400 HUCB transplants have been reported from different centers. It has been suggested that there is a reduced graft‐versus‐host‐disease (GVHD) with HUCB compared to bone marrow transplantation. Since cytokine production by a cell is an indication of the cells function it is important to determinate the differences between APB and HUCB with respect to production of these soluble factors. Our aim was to analyse the intracellular cytokine production by HUCB and APB T lymphocytes with and emphasize on their possible role in GVHD.