On the prebiotic selection of nucleotide anomers: A computational study.

Present-day known predominance of the ß- over the α-anomers in nucleosides and nucleotides emerges from a thermodynamic analysis of their assembly from their components, i.e. bases, sugars, and a phosphate group. Furthermore, the incorporation of uracil into RNA and thymine into DNA rather than the other way around is also predicted from the calculations. An interplay of kinetics and thermodynamics must have driven evolutionary selection of life's building blocks. In this work, based on quantum chemical calculations, we focus on the latter control as a tool for "natural selection".

Next-generation sequencing can reveal in vitro-generated PCR crossover products: some artifactual sequences correspond to HLA alleles in the IMGT/HLA database.

The high-resolution human leukocyte antigen (HLA) genotyping assay that we developed using 454 sequencing and Conexio software uses generic polymerase chain reaction (PCR) primers for DRB exon 2. Occasionally, we observed low abundance DRB amplicon sequences that resulted from in vitro PCR 'crossing over' between DRB1 and DRB3/4/5. These hybrid sequences, revealed by the clonal sequencing property of the 454 system, were generally observed at a read depth of 5%-10% of the true alleles. They usually contained at least one mismatch with the IMGT/HLA database, and consequently, were easily recognizable and did not cause a problem for HLA genotyping. Sometimes, however, these artifactual sequences matched a rare allele and the automatic genotype assignment was incorrect. These observations raised two issues: (1) could PCR conditions be modified to reduce such artifacts? and (2) could some of the rare alleles listed in the IMGT/HLA database be artifacts rather than true alleles? Because PCR crossing over occurs during late cycles of PCR, we compared DRB genotypes resulting from 28 and (our standard) 35 cycles of PCR. For all 21 cell line DNAs amplified for 35 cycles, crossover products were detected. In 33% of the cases, these hybrid sequences corresponded to named alleles. With amplification for only 28 cycles, these artifactual sequences were not detectable. To investigate whether some rare alleles in the IMGT/HLA database might be due to PCR artifacts, we analyzed four samples obtained from the investigators who submitted the sequences. In three cases, the sequences were generated from true alleles. In one case, our 454 sequencing revealed an error in the previously submitted sequence.

Esencia de menta al 1, 6% como espasmolítico intestinalen la colangiopancreatografía retrógrada endoscópica / 1.6% Peppermint oil solution as intestinal spasmolytic in retrograde endoscopic cholangiopancreatography

Objetivos: La aparición de peristaltismo intestinal puede dificultar la realización de exploraciones o intervenciones mediante colangiopancreatografía retrógrada endoscópica(CPRE). Con el fin de disminuirlo es frecuente la utilización de espasmolíticos sistémicos, pese a los efectos adversos anticolinérgicos que presentan. Se propuso formular una preparación de esencia de menta al 1,6% de uso local para evitar estos efectos adversos. Método: Se formuló la preparación de la esencia de menta al 1,6% según la bibliografía encontrada. La efectividad de la fórmula fue valorada de manera semicualitativa según la disminución del peristaltismo. Resultados: Se ensayaron 2 emulgentes siendo polisorbato el más adecuado. El estudio piloto llevado a cabo en 8 pacientes demostró su efectividad y seguridad en la disminución del peristaltismo intestinal. Conclusiones: La esencia de menta al 1,6% constituye una alternativa efectiva y segura a la utilización de espasmolíticos sistémicos. Se requieren posteriores estudios incluyendo un mayor número de pacientes para establecer su utilidad en la práctica clínica habitual (AU)

Objectives: Intestinal peristalsis can impede explorations and interventions using retrograde endoscopic cholangiopancreatography. Systemic spasmolytics are frequently employed to reduce this phenomenon, in spite of the adverse anti-cholinergic effects they are associated with. We proposed a formula using 1.6% peppermint oil solution with local use in order to avoid these adverse side effects. Method: We formulated a preparation of 1.6% peppermint oil solution in accordance with the medical literature. The effectiveness of the formula was evaluated in a semi-qualitative manneraccording to the reduction in peristalsis. Results: We tested two different emulgents, and polysorbate provided the best results. The pilot study carried out with 8 patients demonstrated its effectiveness and safety in reducing intestinal peristalsis. Conclusions: 1.6% peppermint oil solution constitutes an effective and safe alternative to the use of systemic spasmolytics. More studies are needed with a larger sample size in order to establish its usefulness in normal clinical practice (AU)

Increased HLA class I and II diversity as 72 novel alleles are identified in volunteers for the National Marrow Donor Program Registry in 2010.

Seventy-two novel human leukocyte antigen (HLA) class I and class II alleles are described from volunteers for the 'Be The Match Registry®': 17 HLA-A alleles, 12 HLA-C alleles, 31 HLA-B alleles and 12 HLA-DRB1 alleles. Forty-six (≈ 64%) of the 72 novel alleles are single-nucleotide substitution variants when compared with their most homologous allele. Five of these single-nucleotide variants are silent substitutions and one creates a non-expressed allele (B*44:108N). The remaining novel alleles differ from their most similar allele by two to five nucleotide substitutions. One of the novel HLA-C alleles (C*07:150Q) is of questionable expression due to an insertion of 21 nucleotides starting at codon 143 that adds seven amino acids to exon 3. An inter-locus gene conversion may have created the novel allele HLA-A*23:31 that shares its codon differences with HLA-B*07:28. Some of the new alleles encode novel codons and unique amino acid changes at polymorphic positions in the HLA-A (codons 116 and 150), HLA-C (codon 114), HLA-B (codons 11, 21, 35, 42, 48, 73, 98 and 170) and HLA-DRB1 (codon 29) loci.

[1.6% peppermint oil solution as intestinal spasmolytic in retrograde endoscopic cholangiopancreatography]. / Esencia de menta al 1,6% como espasmolítico intestinal en la colangiopancreatografía retrógrada endoscópica.

OBJECTIVES: Intestinal peristalsis can impede explorations and interventions using retrograde endoscopic cholangiopancreatography. Systemic spasmolytics are frequently employed to reduce this phenomenon, in spite of the adverse anti-cholinergic effects they are associated with. We proposed a formula using 1.6% peppermint oil solution with local use in order to avoid these adverse side effects. METHOD: We formulated a preparation of 1.6% peppermint oil solution in accordance with the medical literature. The effectiveness of the formula was evaluated in a semi-qualitative manner according to the reduction in peristalsis. RESULTS: We tested two different emulgents, and polysorbate provided the best results. The pilot study carried out with 8 patients demonstrated its effectiveness and safety in reducing intestinal peristalsis. CONCLUSIONS: 1.6% peppermint oil solution constitutes an effective and safe alternative to the use of systemic spasmolytics. More studies are needed with a larger sample size in order to establish its usefulness in normal clinical practice.

Novel HLA class I and II alleles identified during routine registry typing in 2010.

Twenty-one novel human leukocyte antigen (HLA) class I and class II alleles are described: seven HLA-A alleles, five HLA-C alleles, five HLA-B alleles and four HLA-DRB1 alleles. Seventeen (∼81%) of the 21 novel alleles are single nucleotide substitution variants when compared with their most homologous allele. Nine of these single nucleotide variants cause an amino acid substitution, while eight are silent substitutions. The remaining novel alleles differ from their most similar allele by two to three nucleotide substitutions. One novel HLA-C locus allele encodes an amino acid change at codon 10 that previously has not been reported to be polymorphic for this locus. Some of the new alleles encode novel codons and unique amino acid changes at polymorphic positions in the HLA-A (codons 24 and 156) and HLA-B (codons 40 and 115) loci.

Ninety-six novel HLA class I and II alleles identified in volunteers for the National Marrow Donor Program Registry in 2009.

Ninety-six novel human leukocyte antigen (HLA) class I and class II alleles are described from volunteers for the 'Be The Match Registry®': 15 HLA-A alleles, 11 HLA-C alleles, 36 HLA-B alleles and 34 HLA-DRB1 alleles. Sixty-eight (∼71%) of the 96 novel alleles are single nucleotide substitution variants when compared with their most homologous allele. Twenty-three of these single nucleotide variants are silent substitutions and one creates a non-expressed allele (B(*) 27:59N). The remaining novel alleles differ from their most similar allele by two to five nucleotide substitutions. One of the novel HLA-A alleles (A(*) 11:52Q) is of questionable expression because of a deletion of codon 11. Three of the novel alleles encode amino acid changes at codons 63 (HLA-C), 88 (HLA-B) and 79 (HLA-DRB1) which have not previously been reported to be polymorphic in these loci. Some of the new alleles encode novel codons and unique amino acid changes at polymorphic positions in the HLA-A (codons 115, 149 and 168), HLA-C (codon 90), HLA-B (codons 23, 44, 70, 120 and 153) and HLA-DRB1 (codon 88) loci.

Seventy-eight novel HLA class I and II alleles identified during routine registry typing in 2008 and 2009.

Seventy-eight novel human leukocyte antigen (HLA) class I and class II alleles are described: 19 HLA-A alleles, 30 HLA-C alleles, 21 HLA-B alleles, 7 HLA-DRB1 alleles and 1 HLA-DPB1 allele. Eight (∼10%) of the novel alleles were found in more than one individual and may be more common in the population. Sixty-two (∼80%) of the 78 novel alleles are single nucleotide substitution variants when compared with their most homologous allele. Twelve of these single nucleotide variants are silent substitutions and one creates a null allele (C*08:26N). One of the novel HLA-C alleles, C*03:58, is a hybrid that likely resulted from an intra-locus recombination. The remaining novel alleles differ from their most similar allele by two to seven nucleotide substitutions. Four of the novel HLA-C alleles encode amino acid changes at codons 41, 42, 55 or 200 which have not previously been reported to be polymorphic. Some of the new alleles encode novel codons and unique amino acid changes at polymorphic positions in the HLA-A (codons 55 and 120), HLA-C (codons 151, 153 and 176), HLA-B (codons 31 and 84) and HLA-DRB1 (codon 47) loci.

Sixty-five novel alleles at the HLA-A, -B, and -DRB1 loci identified from National Marrow Donor Program volunteer donors.

Sixty-five novel human leukocyte antigen (HLA) alleles are described from volunteer donors of the 'Be The Match Registry': 29 HLA-A alleles, 24 HLA-B alleles, and 12 HLA-DRB1 alleles. Eight (∼12%) of the novel alleles were found in more than one individual and may be more common in the population. Forty (∼62%) of the 65 novel alleles are single nucleotide substitution variants when compared with their most homologous allele. Two of these single nucleotide variants are silent substitutions and one creates a null allele. The remaining novel alleles differ from their most similar allele by 2-10 nucleotide substitutions. Some of the novel alleles encode amino acid changes at codons not previously reported to be polymorphic, such as codons 23, 93, 129, and 155 in HLA-A alleles and codon 3 in HLA-B alleles.

Description of novel class I alleles encountered during routine registry typing in 2007.

Twenty-six novel human leukocyte antigen (HLA) class I alleles are described: 3 HLA-A alleles, 19 HLA-B alleles and 4 HLA-C alleles. Only one of the novel alleles (HLA-B*0753) was found in multiple individuals and likely is not uncommon in the population. Nineteen (approximately 70%) of the 26 novel alleles are single nucleotide substitution variants when compared with their most homologous allele. Four of these single nucleotide variants are silent substitutions, and one creates a null allele. The remaining novel alleles differ from their most similar allele by two to six nucleotide substitutions. Some of the new alleles encode novel codons and unique amino acid changes at polymorphic positions in the HLA-B lows (codons 30, 67 and 72), while HLA-Cw*0347 encodes an amino acid change at a position not previously reported to be polymorphic for this locus.

Evaluating the potential impact of mismatches outside the antigen recognition site in unrelated hematopoietic stem cell transplantation: HLA-DRB1*1454 and DRB1*140101.

DNA sequencing of 268 individuals drawn from four US populations carrying two unresolved DRB1*14 alleles differing only outside the antigen recognition site identified DRB1*1454 in the majority. A database of 4222 human leukocyte antigen (HLA)-matched hematopoietic stem cell transplantation donor-recipient pairs was queried to determine the number likely mismatched for DRB1*140101/DRB1*1454 but matched for class I loci. A power calculation suggests that more than 88,000 transplants among European Americans will be needed to identify sufficient 7/8 allele-matched pairs to evaluate the impact of the DRB1*140101/DRB1*1454 mismatch on transplant outcome. Molecular modeling of the HLA-DR interaction with the T-cell receptor and with CD4 suggests that the amino acid substitution distinguishing the two alleles will have minimal impact on allorecognition.

Characterization of 104 novel alleles at the HLA-A, -B, and -DRB1 loci from National Marrow Donor Program volunteer donors.

One hundred and four novel human leukocyte antigen (HLA) alleles are described from volunteer donors of the National Marrow Donor Program: 37 HLA-A alleles, 37 HLA-B alleles, and 30 HLA-DRB1 alleles. Seventeen ( approximately 16%) of the novel alleles were found in multiple individuals and likely are relatively common in the population. Seventy-two ( approximately 69%) of the 104 novel alleles are single nucleotide substitution variants when compared with their most homologous allele. Nine of these single nucleotide variants are silent substitutions and three create null alleles. The remaining novel alleles differ from their most similar allele by two to seven nucleotide substitutions. Some of the novel alleles encode amino acid changes at positions not previously reported to be polymorphic, such as codons 6 and 11 in HLA-A alleles and codons 5, 105, and 141 in HLA-B alleles. Interestingly, one of the novel HLA-DRB1 alleles (*1471) has a change that is not the typical glycine/valine dimorphism at codon 86, which plays a key role in peptide binding to DR molecules. This is only the second DRB1 allele described that encodes an amino acid other than glycine or valine at this position.

Characterization of new HLA-B and -DRB1 alleles from Singapore.

Six novel alleles, three human leukocyte antigen (HLA)-B and three HLA-DRB1 alleles, are described. Five of the variants are single nucleotide substitutions from their most homologous allele, of which three result in amino acid changes (B*3572, *9509 and DRB1*1157) and two are silent substitutions (B*370103 and DRB1*150204). DRB1*0462 differs by three nucleotide substitutions that alter two amino acids.

Novel alleles at the HLA-DRB1 and -DQB1 loci.

Twelve novel human leukocyte antigen class II alleles are described; eight DRB1 alleles and four DQB1 alleles. Nine of the variants are single nucleotide substitutions from their most homologous allele, of which six result in amino acid changes (DRB1*0459, *1156 and *1522; DQB1*0205, *0320 and *0321) and three are silent substitutions (DRB1*030105 and *040304, and DQB1*030104). The remaining alleles (DRB1*0906, *1464 and *1468) differ from their most similar alleles by two to three nucleotide substitutions which alter one to two amino acids.

Identification of 11 novel HLA alleles found during typing of unrelated registry donors in China.

Eleven novel human leukocyte antigen (HLA) alleles were identified during routine sequence-specific oligonucleotide probe (SSOP) typing (LABType; One Lambda Inc., Los Angeles, CA) of volunteers for a hematopoietic stem cell registry in Beijing, China. The new alleles were detected when one or more probes gave an unexpected reactivity pattern.

Twenty-three novel alleles increase diversity at the HLA-C locus.

Twenty-three novel HLA-C alleles are described. Nine of the new alleles are single-nucleotide substitutions from their most homologous allele of which seven result in amino acid changes (Cw*0327, *0508, *0514, *0613, *0735, *0739 and *1517) and two are silent substitutions (Cw*030305 and *070107). The remaining 14 alleles (Cw*0113, *0207, *0212, *0216, *0318, *0411, *0417, *0512, *0722, *0733N, *1216, *1218, *1515 and *1607) differ from their most similar alleles by 2-4 nucleotide substitutions that result in 1-3 amino acid differences.

Expanding diversity at the HLA-B locus: 28 novel HLA-B alleles.

Twenty-eight novel human leukocyte antigen-B alleles are described: one B*07 (*0745), two B*08 (*0826 and *0831), one B*27 (*2731), four B*35 (*350106, *350402, *3566, and *3568), two B*37 (*370102 and *3711), two B*38 (*380102 and *3813), two B*39 (*3935 and *3939), one B*41 (*4108), one B*42 (*4209), two B*44 (*4444 and *4448), two B*48 (*480302 and *4815), one B*51 (*5140), one B*55 (*5523), one B*56 (*5617), two B*57 (*570103 and *5710), and three B*15 (*9505, *9510, and *9519). Sixteen of the variants are single-nucleotide substitutions from their most homologous allele, of which 10 result in amino acid changes (B*0745, *0831, *3813, *3935, *3939, *4815, *9505, *9509, *9510, and *9519) and 6 are silent substitutions. The remaining alleles (B*0826, *2731, *3566, *3568, *3711, *4108, *4209, *4444, *4448, *5140, *5523, *5617, and *5710) differ from their most similar alleles by two to seven nucleotides substitutions, altering from one to five amino acids.

Thirty-two novel HLA-A alleles identified during intermediate resolution testing.

Thirty-two novel human leukocyte antigen-A alleles are described: four A*01 (*0110, *0112, *0113 and *0117), four A*02 (*0263, *0280, *0292 and *9201), two A*03 (*0316 and *0325), four A*11 (*111502, *1117, *1122 and *1123), five A*24 (*2441, *2450, *2455, *2456 and *2457), one A*26 (*2627), two A*29 (*2909 and *2914), two A*30 (*3013 and *3016), one A*32 (A*3213), two A*34 (*3407 and *3408) and five A*68 (*6828, *6829, *6830, *6831 and *6834). Seventeen of the variants are single-nucleotide substitutions from their most homologous allele, which results in amino acid changes (A*0117, *0263, *0292, *0316, *0325, *1122, *1123, *2455, *2456, *2457, *2627, *2909, *3016, *3407, *6828, *6831 and *6834), and only one is silent substitution (A*111502). The remaining alleles differ from their most similar alleles by two to six nucleotide substitutions.

Characterization of seven new HLA alleles from the Henan and Gansu Provinces of China.

Four new class I and three class II alleles have been found in Chinese individuals.

Identification of two new HLA-B alleles, HLA-B*4069 and B*5409, in the Liaoning province of China.

Two new human leukocyte antigen-B alleles, B*4069 and B*5409, were identified in China.