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Arabinogalactans (AGs) are structural polysaccharides of the plant cell wall. A small proportion of the AGs are associated with hemicellulose and pectin. Furthermore, AGs are associated with proteins forming the so-called arabinogalactan proteins (AGPs), which can be found in the plant cell wall or attached through a glycosylphosphatidylinositol (GPI) anchor to the plasma membrane. AGPs are a family of highly glycosylated proteins grouped with cell wall proteins rich in hydroxyproline. These glycoproteins have important and diverse functions in plants, such as growth, cellular differentiation, signaling, and microbe-plant interactions, and several reports suggest that carbohydrate components are crucial for AGP functions. In beneficial plant-microbe interactions, AGPs attract symbiotic species of fungi or bacteria, promote the development of infectious structures and the colonization of root tips, and furthermore, these interactions can activate plant defense mechanisms. On the other hand, plants secrete and accumulate AGPs at infection sites, creating cross-links with pectin. As part of the plant cell wall degradation machinery, beneficial and pathogenic fungi and bacteria can produce the enzymes necessary for the complete depolymerization of AGs including endo-β-(1,3), β-(1,4) and β-(1,6)-galactanases, β-(1,3/1,6) galactanases, α-L-arabinofuranosidases, β-L-arabinopyranosidases, and β-D-glucuronidases. These hydrolytic enzymes are secreted during plant-pathogen interactions and could have implications for the function of AGPs. It has been proposed that AGPs could prevent infection by pathogenic microorganisms because their degradation products generated by hydrolytic enzymes of pathogens function as damage-associated molecular patterns (DAMPs) eliciting the plant defense response. In this review, we describe the structure and function of AGs and AGPs as components of the plant cell wall. Additionally, we describe the set of enzymes secreted by microorganisms to degrade AGs from AGPs and its possible implication for plant-microbe interactions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Villa-Rivera, Cano-Camacho, López-Romero and Zavala-Páramo.)

Bovine mastitis, an inflammation of the mammary gland of dairy cattle, is the most prevalent disease causing economically important losses, reduced milk production, early culling, veterinary expenses, and higher death rates. Bovine mastitis infections are the main cause for the use of antibiotics; however, the emergence of multidrug-resistant bacteria and the poor or nil response to antibiotics has become a critical global health problem. The goal of this study was the characterization of bacterial infections associated with clinical bovine mastitis. All the isolates were multidrug-resistant and were negative for the production of extended spectrum β-lactamases. However, all isolates were identified as carbapenemase-producing organisms by the Carba NP test. The carbapenemase identified was the product of the KPC-2 gene. The isolates were identified as Klebsiella pneumoniae and contained virulence genes for fimbriae, lipopolysaccharides, nitrogen starvation genes, and siderophores. Sixty-nine percent of the KPC-2-producing isolates had the same plasmid profile, although the genetic mobilization of resistance by bacterial conjugation was unsuccessful. The carbapenemase corresponded to the plasmid-borne KPC-2 gene identified by Southern blot hybridization. The assay showed a positive signal in the 90 kb (69% of the isolates), 165 kb (31% of the isolates), and 130 kb (6% of the isolates) plasmids. The IncFII y and IncFII k replicons were detected among these K. pneumoniae isolates. The PFGE and MLST analysis showed that all of the isolates are comprised by two clones (A and B) belonging to Sequence Type 258. This is the first report of K. pneumoniae producing carbapenemase KPC-2 isolated from bovine mastitis.

Background: The Orange-fronted Parakeet (Eupsittula canicularis) is the Mexican psittacine that is most captured for the illegal pet trade. However, as for most wildlife exploited by illegal trade, the genetic diversity that is extracted from species and areas of intensive poaching is unknown. In this study, we analyzed the genetic diversity of 80 E. canicularis parakeets confiscated from the illegal trade and estimated the level of extraction of genetic diversity by poaching using the mitochondrial DNA sequences of cytochrome b (Cytb). In addition, we analyzed the genealogical and haplotypic relationships of the poached parakeets and sampled wild populations in Mexico, as a strategy for identifying the places of origin of poached parakeets., Results: Poached parakeets showed high haplotype diversity (Hd = 0.842) and low nucleotide diversity (Pi = 0.00182). Among 22 haplotypes identified, 18 were found exclusively in 37 individuals, while four were detected in the remaining 43 individuals and shared with the wild populations. A rarefaction and extrapolation curve revealed that 240 poached individuals can include up to 47 haplotypes and suggested that the actual haplotype richness of poached parakeets is higher than our analyses indicate. The geographic locations of the four haplotypes shared between poached and wild parakeets ranged from Michoacan to Sinaloa, Mexico. However, the rare haplotypes detected in poached parakeets were derived from a recent genetic expansion of the species that has occurred between the northwest of Michoacan and the coastal region of Colima, Jalisco and southern Nayarit, Mexico., Conclusions: Poached parakeets showed high genetic diversity, suggesting high extraction of the genetic pool of the species in central Mexico. Rarefaction and extrapolation analyses suggest that the actual haplotype richness in poached parakeets is higher than reflected by our analyses. The poached parakeets belong mainly to a very diverse genetic group of the species, and their most likely origin is between northern Michoacan and southern Nayarit, Mexico. We found no evidence that poachers included individuals from Central American international trafficking with individuals from Mexico in the sample., (© 2021. The Author(s).)

Aim: This report presents phenotypic and genetic data on the prevalence and characteristics of extended-spectrum β-lactamases (ESBLs) and representative carbapenemases-producing Gram-negative species in Mexico., Material and Methods: A total of 52 centers participated, 43 hospital-based laboratories and 9 external laboratories. The distribution of antimicrobial resistance data for Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae complex, Acinetobacter baumannii complex, and Pseudomonas aeruginosa in selected clinical specimens from January 1 to March 31, 2020 was analyzed using the WHONET 5.6 platform. The following clinical isolates recovered from selected specimens were included: carbapenem-resistant Enterobacteriaceae, ESBL or carbapenem-resistant E. coli, and K. pneumoniae, carbapenem-resistant A. baumannii complex, and P. aeruginosa. Strains were genotyped to detect ESBL and/or carbapenemase-encoding genes., Results: Among blood isolates, A. baumannii complex showed more than 68% resistance for all antibiotics tested, and among Enterobacteria, E. cloacae complex showed higher resistance to carbapenems. A. baumannii complex showed a higher resistance pattern for respiratory specimens, with only amikacin having a resistance lower than 70%. Among K. pneumoniae isolates, blaTEM, blaSHV, and blaCTX were detected in 68.79%, 72.3%, and 91.9% of isolates, respectively. Among E. coli isolates, blaTEM, blaSHV, and blaCTX were detected in 20.8%, 4.53%, and 85.7% isolates, respectively. For both species, the most frequent genotype was blaCTX-M-15. Among Enterobacteriaceae, the most frequently detected carbapenemase-encoding gene was blaNDM-1 (81.5%), followed by blaOXA-232 (14.8%) and blaoxa-181(7.4%), in A. baumannii was blaOXA-24 (76%) and in P. aeruginosa, was blaIMP (25.3%), followed by blaGES and blaVIM (13.1% each)., Conclusion: Our study reports that NDM-1 is the most frequent carbapenemase-encoding gene in Mexico in Enterobacteriaceae with the circulation of the oxacillinase genes 181 and 232. KPC, in contrast to other countries in Latin America and the USA, is a rare occurrence. Additionally, a high circulation of ESBL blaCTX-M-15 exists in both E. coli and K. pneumoniae., Competing Interests: The authors have declared that no competing interests exist.

Carbapenem-resistant Gram-negative bacteria isolated in Venezuela have been poorly characterized. The present study characterized a total of 34 isolates obtained from 27 patients; five of these patients were multi-infected. The bacterial species identified were Klebsiella pneumoniae (17), Pseudomonas aeruginosa (9), and Acinetobacter baumannii (8). From these isolates, 85% were identified as carbapenemase-producing bacteria, and the identified carbapenemase genes were bla KPC-2 (10/29 [34.4%]), bla VIM-type (7/29 [24.1%]), bla OXA-23 (7/29 [24.1%]), bla NDM-1 (8/29 [27.5%]), and the coexistence of bla OXA-23 / bla NDM-1 (2/29 [6.8%]). Patient 1 was multi-infected by K. pneumoniae ST11 and ST2413 isolates harbouring the bla NDM-1 and bla KPC-2 genes, respectively. The other patients were multi-infected by two or three different bacterial species such as ESBL-producing K. pneumoniae isolates, P. aeruginosa harbouring the bla VIM-type gene, K. pneumoniae ST147 harbouring the bla KPC-2 gene and by A. baumannii harbouring the bla OXA-23 gene. The bla NDM-1 gene in A. baumannii is flanked by an uncommon genetic structure, whereas bla NDM-1 gene in K. pneumoniae revealed a common structure described in different plasmids from Enterobacteriaceae isolates. This study provides new information about the epidemiology of carbapenemase-producing bacteria in clinical setting in Venezuela.

Background: Cancer patients are at increased risk of infection. Fecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) may increase this risk. There are few studies on the prevalence of ESBL-PE colonization and surgical site infections (SSIs)., Methods: This prospective cohort study included patients with gastrointestinal and gynecological malignancies who were admitted to the hospital for elective surgery. Rectal swab cultures were obtained on the day of admission and during the postoperative period every 5 days. Prevalence of ESBL-PE fecal colonization and risk factors for the development of SSI were assessed., Results: We included 171 patients, 30 (17.5%) of whom were colonized with ESBL-PE at admission. This proportion increased to 21% (37 of 171) of the samples during the hospital stay. Incidence of SSI was 14.6% (n = 25). Ten of 37 (27%) patients colonized by ESBL-PE developed SSI versus 15 of 134 (11%) of the non-ESBL-PE (relative risk [RR], 2.163; 95% confidence interval [CI], 1.201-3.897; P = .016). Five patients developed a bloodstream infection, and 4 patients were colonized with ESBL-PE (RR = 4.02; 95% CI, 1.2-3.89; P = .008)., Conclusions: The rate of ESBL-PE fecal colonization in surgical patients was 17.5%. Colonization of ESBL-PE duplicated the risk of SSI by the same strain and, by a factor of 4, the risk of bloodstream infections., (Copyright © 2019. Published by Elsevier Inc.)

Klebsiella variicola is considered an emerging pathogen in humans and has been described in different environments. K. variicola belongs to Klebsiella pneumoniae complex, which has expanded the taxonomic classification and hindered epidemiological and evolutionary studies. The present work describes the molecular epidemiology of K. variicola based on MultiLocus Sequence Typing (MLST) developed for this purpose. In total, 226 genomes obtained from public data bases and 28 isolates were evaluated, which were mainly obtained from humans, followed by plants, various animals, the environment and insects. A total 166 distinct sequence types (STs) were identified, with 39 STs comprising at least two isolates. The molecular epidemiology of K. variicola showed a global distribution for some STs was observed, and in some cases, isolates obtained from different sources belong to the same ST. Several examples of isolates corresponding to kingdom-crossing bacteria from plants to humans were identified, establishing this as a possible route of transmission. goeBURST analysis identified Clonal Complex 1 (CC1) as the clone with the greatest distribution. Whole-genome sequencing of K. variicola isolates revealed extended-spectrum β-lactamase- and carbapenemase-producing strains with an increase in pathogenicity. MLST of K. variicola is a strong molecular epidemiological tool that allows following the evolution of this bacterial species obtained from different environments.

Objectives: This study investigated the presence of the crpP gene, which encodes an enzymatic mechanism of antibiotic phosphorylation that decreases ciprofloxacin susceptibility, in ESBL-producing clinical isolates and its effect in transconjugants., Methods: A collection of 77 ESBL-producing clinical isolates of Enterobacteriaceae and 68 ESBL-producing transconjugants that had acquired plasmids from clinical isolates from hospitals in Mexico obtained from 1988 to 2012 was employed. The crpP homologue genes were identified by dot-blot and PCR assays; five of them were sequenced and an in silico analysis was conducted. Expression of CrpP proteins was determined by western blot assays using antibodies against CrpP from plasmid pUM505. Three crpP homologue genes were cloned and transferred to Escherichia coli J53-3 as recipient strain., Results: The crpP gene was identified in four (5.19%) ESBL-producing isolates and five (7.35%) ESBL-producing transconjugants with plasmids from clinical isolates. Analysis of the deduced amino acid (aa) sequence of the CrpP protein homologues revealed that they all corresponded to small proteins (63-70 aa) with an identity of 10.1%-43.7% with respect to the pUM505 CrpP sequence. In addition, all crpP-positive transconjugants expressed a CrpP protein. Finally, transfer of crpP homologues conferred lower ciprofloxacin susceptibility to E. coli., Conclusions: These findings indicate the presence of crpP genes among ESBL-producing isolates from Mexican hospitals and point to widespread crpP-type genes in old Enterobacteriaceae clinical isolates (from 1994). CrpP probably confers resistance by means of the phosphorylation of ciprofloxacin., (© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

The Klebsiella pneumoniae complex comprises seven K. pneumoniae- related species, including K. variicola . K. variicola is a versatile bacterium capable of colonizing different hosts such as plants, humans, insects and animals. Currently, K. variicola is gaining recognition as a cause of several human infections; nevertheless, its virulence profile is not fully characterized. The clinical significance of K. variicola infection is hidden by imprecise detection methods that underestimate its real prevalence; however, several methods have been developed to correctly identify this species. Recent studies of carbapenemase-producing and colistin-resistant strains demonstrate a potential reservoir of multidrug-resistant genes. This finding presents an imminent scenario for spreading antimicrobial resistant genes among close relatives and, more concerningly, in clinical and environmental settings. Since K. variicola was identified as a novel bacterial species, different research groups have contributed findings elucidating this pathogen; however, important details about its epidemiology, pathogenesis and ecology are still missing. This review highlights the most significant aspects of K. variicola , discussing its different phenotypes, mechanisms of resistance, and virulence traits, as well as the types of infections associated with this pathogen.

Background: The distribution of the wild turkey (Meleagris gallopavo) extends from Mexico to southeastern Canada and to the eastern and southern regions of the USA. Six subspecies have been described based on morphological characteristics and/or geographical variations in wild and domesticated populations. In this paper, based on DNA sequence data from the mitochondrial D-loop, we investigated the genetic diversity and structure, genealogical relationships, divergence time and demographic history of M. gallopavo populations including domesticated individuals., Results: Analyses of 612 wild and domesticated turkey mitochondrial D-loop sequences, including 187 that were collected for this study and 425 from databases, revealed 64 haplotypes with few mutations, some of which are shared between domesticated and wild turkeys. We found a high level of haplotype and nucleotide diversity, which suggests that the total population of this species is large and stable with an old evolutionary history. The results of genetic differentiation, haplotype network, and genealogical relationships analyses revealed three main genetic groups within the species: mexicana as a population relict (C1), merriami (C2), and mexicana/intermedia/silvestris/osceola (C3). Haplotypes detected in domesticated turkeys belong to group C3. Estimates of divergence times agree with range expansion and diversification events of the relict population of M. gallopavo in northwestern Mexico during the Pliocene-Pleistocene and Pleistocene-Holocene boundaries. Demographic reconstruction showed that an expansion of the population occurred 110,000 to 130,000 years ago (Kya), followed by a stable period 100 Kya and finally a decline ~ 10 Kya (Pleistocene-Holocene boundary). In Mexico, the Trans-Mexican Volcanic Belt may be responsible for the range expansion of the C3 group. Two haplotypes with different divergence times, MGMDgoB/MICH1 and MICH2, are dominant in domesticated and commercial turkeys., Conclusions: During the Pleistocene, a large and stable population of M. gallopavo covered a wide geographic distribution from the north to the center of America (USA and Mexico). The mexicana, merriami, and mexicana/intermedia/silvestris/osceola genetic groups originated after divergence and range expansion from northwestern Mexico during the Pliocene-Pleistocene and Pleistocene-Holocene boundaries. Old and new maternal lines of the mexicana/intermedia/silvestris/osceola genetic group were distributed within the Trans-Mexican Volcanic Belt where individuals were captured for domestication. Two haplotypes are the main founder maternal lines of domesticated turkeys.

Endophytic Klebsiella variicola KvMx2 and Klebsiella pneumoniae KpMx1 isolates obtained from the same sugarcane stem were used for whole-genome sequencing. The genomes revealed clear differences in essential genes for plant growth, development, and detoxification, as well as nitrogen fixation, catalases, cellulases, and shared virulence factors described in the K. pneumoniae pathogen., (Copyright © 2018 Reyna-Flores et al.)

Objective: Due to the fact that K. variicola, K. quasipneumoniae and K. pneumoniae are closely related bacterial species, misclassification can occur due to mistakes either in normal biochemical tests or during submission to public databases. The objective of this work was to identify K. variicola and K. quasipneumoniae genomes misclassified in GenBank database., Materials and Methods: Both rpoB phylogenies and average nucleotide identity (ANI) were used to identify a significant number of misclassified Klebsiella spp. genomes., Results: Here we report an update of K. variicola and K. Quasipneumoniae genomes correctly classified and a list of isolated genomes obtained from humans, plants, animals and insects, described originally as K. pneumoniae or K. variicola, but known now to be misclassified., Conclusions: This work contributes to recognize the extensive presence of K. variicola and K. quasipneumoniae isolates in diverse sites and samples., Competing Interests: Declaration of conflict of interests. The authors declare that they have no conflict of interests.

Since the hypermucoviscous variants of Klebsiella pneumoniae were first reported, many cases of primary liver abscesses and other invasive infections caused by this pathogen have been described worldwide. Hypermucoviscosity is a phenotypic feature characterized by the formation of a viscous filament ≥5 mm when a bacterial colony is stretched by a bacteriological loop; this is the so-called positive string test. Hypermucoviscosity appears to be associated with this unusual and aggressive type of infection, and therefore, the causal strains are considered hypervirulent. Since these first reports, the terms hypermucoviscosity and hypervirulence have often been used synonymously. However, new evidence has suggested that hypermucoviscosity and hypervirulence are 2 different phenotypes that should not be used synonymously. Moreover, it is important to establish that a negative string test is insufficient in determining whether a strain is or is not hypervirulent. On the other hand, hypervirulence- and hypermucoviscosity-associated genes must be identified, considering that these phenotypes correspond to 2 different phenomena, regardless of whether they can act in synergy under certain circumstances. Therefore, it is essential to quickly identify the genetic determinants behind the hypervirulent phenotype to develop effective methodologies that can diagnose in a prompt and effective way these hypervirulent variants of K. pneumoniae.

Pectin lyases (PNLs) are important enzymes that are involved in plant cell wall degradation during the infection process. Colletotrichum is a diverse genus of fungi, which allows the study of the evolution of PNLs and their possible role in pathogen-host interactions and lifestyle adaptations. The phylogenetic reconstruction of PNLs from Colletotrichum and analysis of selection pressures showed the formation of protein lineages by groups of species with different selection pressures and specific patterns. The analysis of positive selection at individual sites using different methods allowed for the identification of three codons with evidence of positive selection in the oligosaccharide-binding region and two codons on the antiparallel sheet, which may influence the interaction with the substrate. Seven codons on the surface of the protein, mainly in the peripheral helices of the PNLs, could have an important function in evasion of plant defenses, as has been proposed in other enzymes. According to our results, it is possible that events of genetic duplication occurred in ancestral lines, followed by episodes of genetic diversification and gene loss, probably influenced by differences in the composition of the host cell wall. Additionally, different patterns of evolution in Colletotrichum appear to be molded by a strong purifying selection and positive selection episodes that forged the observed evolutionary patterns, possibly influenced by host interaction or substrate specificity. This work represents a starting point for the study of sites that may be important for evasion of plant defenses and biotechnological purposes.

Hepatitis C virus (HCV) is a significant global public health problem with >185 million infections worldwide. A series of genome-wide association studies (GWAS) has identified IL-28B polymorphisms as a predictor of sustained virologic response (SVR), as well as spontaneous clearance in chronic HCV genotype 1 patients. The objective of this work was to evaluate the prevalence of IL-28B rs12979860 and rs8099917 polymorphisms in Cuban chronic HCV patients. The study cohort included 73 chronic HCV patients treated with concomitant administration of CIGB-230 and nonpegylated IFN-α plus ribavirin (non-pegIFN-α/R) antiviral therapy. The genotype distribution of IL-28B rs12979860CC, -CT, and -TT was 29, 41, and 30%, respectively, and the distribution for rs8099917TT, -TG, and -GG was 63, 31, and 5%, respectively. The allele frequencies for rs12979860C and -T alleles were 51 and 49%, respectively, and for rs8099917G and -T alleles, the values were 21 and 79%, respectively. SVR rates were 55, 42, and 35% for rs12979860CC, -CT, and -TT, respectively, and 52, 30, and 25% for rs8099917TT, -GT, and -GG, respectively. The combined assessment of both single nucleotide polymorphisms (SNPs) resulted in 3 major genotypes (rs12979860CC/rs8099917TT, rs12979860CT/rs8099917TT, and rs12979860CT/rs8099917GG) with a frequency of 30.1, 21.9, and 20.5%, respectively. In patients with heterozygous variant rs12979860CT, the additional genotyping of rs8099917 contributed to increase the SVR rate. It is concluded that in Cuban HCV-infected patients, the responder homogeneous variant rs8099917TT is the most frequent genotype. The simultaneous genotyping of 2 IL-28B SNPs could improve the prediction of SVR contributing to better therapeutic decisions and treatment management.

The Colletotrichum genus has been considered as one of the top 10 fungal pathogens in molecular plant pathology based on their scientific and agrobiological importance. Although the genus contains species with different lifestyles, most of the Colletotrichum sp. are known by their hemibiotrophic strategy of infection/invasion causing anthracnose disease in many economically important crops. Hemibiotrophy includes two sequential stages of infection, biotrophy and necrotrophy, in a series of steps that involve the participation of different virulence factors. In this review, we present the current status of the knowledge of such factors reported in this genus and a list of related genes identified in Colletotrichum sp. genomes., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Purpose: The purpose of this study is to evaluate the impact of fecal extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) colonization for bloodstream infection (BSI), clinical outcome, and costs in patients with hematologic malignancies (HM) and severe neutropenia., Methods: This is a cohort study, carried out at a cancer-referral hospital. The study population comprises patients with HM, hospitalized prior to administration of the first chemotherapy cycle. A stool culture was taken during the first 48 h; they were grouped as colonized by ESBL-EC or non-ESBL-EC. Patients were followed upon completion of chemotherapy or death. The sum of the days of antibiotics and the length of stay of all hospitalizations in the different cycles of chemotherapy were recorded., Results: We included 126 patients with a recent diagnosis of HM, grouped as 63 patients colonized by ESBL-EC and 63 colonized by non-ESBL-EC, aged 42 ± 16 years old, 78 males (62%). BSI by ESBL-EC developed in 14 patients (22.2%) colonized by the same strain and in 5 (7.9%) in the group colonized with non-ESBL-EC. BSI by non-ESBL-EC was observed in 3 patients (4.7%) colonized by ESBL-EC and in 17 (26.9%) patients colonized by non-ESBL-EC. Colonization with ESBL-EC increased the risk of BSI by the same strain (relative risk (RR) = 3.4, 95% confidence interval (95% CI) 1.5-7.8, p = 0.001), shorter time to death (74 ± 62 vs. 95 ± 83 days, p < 0.001), longer hospital stay (64 ± 39 vs. 48 ± 32 days, p = 0.01), and higher infection-related costs ($6528 ± $4348 vs. $4722 ± $3173, p = 0.01). There was no difference in overall mortality between both groups., Conclusions: Fecal colonization by ESBL-EC is associated with increased risk of BSI by this strain, longer hospital stay, and higher related costs.

Background: Microorganisms produce cell-wall-degrading enzymes as part of their strategies for plant invasion/nutrition. Among these, pectin lyases (PNLs) catalyze the depolymerization of esterified pectin by a β-elimination mechanism. PNLs are grouped together with pectate lyases (PL) in Family 1 of the polysaccharide lyases, as they share a conserved structure in a parallel β-helix. The best-characterized fungal pectin lyases are obtained from saprophytic/opportunistic fungi in the genera Aspergillus and Penicillium and from some pathogens such as Colletotrichum gloeosporioides.The organism used in the present study, Colletotrichum lindemuthianum, is a phytopathogenic fungus that can be subdivided into different physiological races with different capacities to infect its host, Phaseolus vulgaris. These include the non-pathogenic and pathogenic strains known as races 0 and 1472, respectively., Results: Here we report the isolation and sequence analysis of the Clpnl2 gene, which encodes the pectin lyase 2 of C. lindemuthianum, and its expression in pathogenic and non-pathogenic races of C. lindemuthianum grown on different carbon sources. In addition, we performed a phylogenetic analysis of the deduced amino acid sequence of Clpnl2 based on reported sequences of PNLs from other sources and compared the three-dimensional structure of Clpnl2, as predicted by homology modeling, with those of other organisms. Both analyses revealed an early separation of bacterial pectin lyases from those found in fungi and oomycetes. Furthermore, two groups could be distinguished among the enzymes from fungi and oomycetes: one comprising enzymes from mostly saprophytic/opportunistic fungi and the other formed mainly by enzymes from pathogenic fungi and oomycetes. Clpnl2 was found in the latter group and was grouped together with the pectin lyase from C. gloeosporioides., Conclusions: The Clpnl2 gene of C. lindemuthianum shares the characteristic elements of genes coding for pectin lyases. A time-course analysis revealed significant differences between the two fungal races in terms of the expression of Clpnl2 encoding for pectin lyase 2. According to the results, pectin lyases from bacteria and fungi separated early during evolution. Likewise, the enzymes from fungi and oomycetes diverged in accordance with their differing lifestyles. It is possible that the diversity and nature of the assimilatory carbon substrates processed by these organisms played a determinant role in this phenomenon.

The genetic diversity and population structure of Escherichia coli isolates from small-scale dairy farms were used to assess the ability of E. coli to spread within the farm environment and between neighboring farms. A total of 164 E. coli isolates were obtained from bovine feces, bedding, cow teats and milk from 6 small-scale dairy farms. Ward's clustering grouped the isolates into 54 different random amplified polymorphic DNA (RAPD) types at 95% similarity, regardless of either the sample type or the farm of isolation. This suggests that RAPD types are shared between bovine feces, bedding, cow teats, and milk. In addition, transmission of RAPD types between the studied farms was suggested by the Ward grouping pattern of the isolates, Nei's and AMOVA population analyses, and genetic landscape shape analysis. For the first time, the latter analytical tool was used to assess the ability of E. coli to disseminate between small-scale dairy farms within the same producing region. Although a number of dispersal mechanisms could exist between farms, the genetic landscape shape analysis associated the flow of E. coli RAPD types with the movement of forage and milking staff between farms. This study will aid in planning disease prevention strategies and optimizing husbandry practices.

Experimental techniques for the identification of genes associated with diseases are expensive and have certain limitations. In this scenario, computational methods are useful tools to identify lists of promising genes for further experimental verification. This paper describes a flexible methodology for the in silico prediction of genes associated with diseases combining the use of available tools for gene enrichment analysis, gene network generation and gene prioritization. A set of reference genes, with a known association to a disease, is used as bait to extract candidate genes from molecular interaction networks and enriched pathways. In a second step, prioritization methods are applied to evaluate the similarities between previously selected candidates and the set of reference genes. The top genes obtained by these programs are grouped into a single list sorted by the number of methods that have selected each gene. As a proof of concept, top genes reported a few years ago in SzGene and AlzGene databases were used as references to predict genes associated to schizophrenia and Alzheimer's disease, respectively. In both cases, we were able to predict a statistically significant amount of genes belonging to the updated lists.

Background: Incidence of type 1 diabetes varies widely around the world, probably due to ethnic differences across populations among other factors., Aims: To determine whether there is an association between disease and ancestry proportions; and to control disease-HLA associations for possible confounding by admixture or population stratification., Subjects and Methods: 100 cases and 129 controls participated in the study. Ancestry informative markers, which have considerable differences in frequency between European, West African and Native American populations were used. Type 1 diabetes associated HLA susceptibility/protection alleles were ascertained by PCR using specific primers. Statistical analyses were conducted using STRUCTURE 2.1, ADMIXMAP 3.7, SPSS 16.0 and STRAT 1.0 packages., Results: The results of logistic regression implemented in ADMIXMAP 3.7 indicated that European ancestry was associated with type 1 diabetes mellitus with an odds ratio of 5.7 corresponding to one unit change in European admixture proportion. Association was found between HLA alleles and disease, DQA1*0501, *0301 DQB1*0201 and DRB1*0301, *0401 being susceptibility alleles and DRB1*1501, DQA1*0102/3 and DQB1*0602 being protective alleles., Conclusions: We found an association between European ancestry and type 1 diabetes in our sample, indicating the contribution of ethnicity to incidence differences. Previously reported associations of HLA DR/DQ alleles with disease are confirmed for the admixed Cuban population.

Published methods to isolate DNA from insects are not always effective in xylophagous insects because they have high concentrations of phenolics and other secondary plant compounds in their digestive tracts. A simple, reliable and labor-effective cetyltrimethylammonium bromide-polyvinylpyrrolidone (CTAB-PVP) method for isolation of high quality DNA from xylophagous insects is described. This method was successfully applied to PCR and restriction analysis, indicating removal of common inhibitors. DNA isolated by the CTAB-PVP method could be used in most molecular analyses.

A distinctive feature of bovine milk fat is the presence of butyrate, molecule with recognized antimicrobial and antiinflammatory properties. Bovine mastitis is a pathology characterized by inflammatory and infectious processes; however, the role of sodium butyrate on Staphylococcus aureus infection in mammary epithelium has not been studied. In this work we assess the role of sodium butyrate on the invasion of bovine mammary epithelial cells (bMEC) by S. aureus responsible of mastitis and on the expression of antimicrobial peptide genes. Our data show that sodium butyrate (0.25-0.5mM) reduces approximately 50% the internalization of S. aureus (ATCC 27543) into bMEC. By RT-PCR analysis, we showed that sodium butyrate is able to up-regulate the expression of tracheal antimicrobial peptide (TAP), beta-defensin and inducible nitric oxide synthase (iNOS) mRNAs, as well as nitric oxide production. Also, sodium butyrate and infection increased acetylation of histone H3 in bMEC. These results indicate that sodium butyrate could be effective to modulate innate immune gene expression in mammary gland that leads to a better defense against bacterial infection. To our knowledge, this is the first report that shows a role of sodium butyrate during the internalization of S. aureus into bMEC.

The extreme polymorphism found at some of the human leukocyte antigen (HLA) system loci makes it an invaluable tool for population genetic analyses. In the present study the genetic polymorphism of the Cuban population was estimated at HLA-A, -B, and -Cw loci by DNA typing. HLA class I allele and haplotype diversity were determined in 390 unrelated Cuban individuals (188 whites and 202 mulattos) from all over the country. In whites 19, 27, and 14 allele families for the HLA-A, -B, and -Cw loci, respectively, were identified. In mulattos, for the same loci, 20, 18, and 14 allele families were identified. Allele and haplotypes frequencies, comparisons with other worldwide populations based on genetic distances, neighbor-joining dendrograms, and correspondence analyses were estimated. Most of the identified allele groups and haplotypes are also common to sub-Saharan African and Europeans populations. However, Amerindian and Asian alleles were also detected at lower frequencies. The results clearly reveal the high diversity and interethnic admixture of the studied population. Our results provide useful information for the further studies of the Cuban population evolution and disease association in terms of HLA class I genes.

Background: The angiotensin converting enzyme (ACE) is a key protein of the renin angiotensin system, whose main function is the conversion of angiotensin I to II. ACE is involved in the physiological control of blood pressure and it is a candidate gene for essential hypertension in humans. We tested the relevance of the ACE insertion/deletion (I/D) polymorphism in our population., Methods: We recruited 243 hypertensive and 407 normotensive subjects in the city of Havana, matched according to age, sex and ethnic group. The ACE (I/D) polymorphism was determined by the polymerase chain reaction (PCR) technique. The fit of genotype frequencies to Hardy-Weinberg proportions was evaluated in all groups analyzed. The possible association between the ACE I/D polymorphism and hypertension status was tested by chi2 and odds ratio tests., Results: All groups but black female cases were in Hardy-Weinberg equilibrium. The frequencies of the D allele in hypertensive/normotensive subjects were 0.61/0.59 in white males, 0.58/0.58 in white females, 0.47/0.59 in black males and 0.58/0.54 in black females. The distribution of ACE genotypes differed significantly between cases and controls only in black women according to the additive model (chi2p=0.04) but the adjusted OR did not show significant association (OR 1.14 95% CI 0.62 to 2.10)., Conclusion: The ACE I/D polymorphism was not associated with hypertension in our multiethnic sample. While the chi2 test for additive model in black women suggested a marginal significance, the adjusted OR did not show any significant association.

Celiac disease (CD) susceptibility has been strongly associated with HLA-DQ2 and HLA-DQ8. The main objective of this study was to assess the distribution of HLA DQA1*0501 and DQB1*02 alleles (DQ2) for the first time in a group of Cuban celiac patients. We evaluated 22 patients, 54 first-degree relatives, and 60 controls for detection of antitissue transglutaminase (tTG)-specific antibodies in serum. We found that 100% of the probands and 19% of the first-degree relatives were positive for the antibodies in serum. We did not detect any specific response for the healthy control individuals. We observed a significant over-representation of DQ2 heterodimer, both in patients and relatives. In the group of patients, 86.3% were positive for DQA1*0501, 90.2% were positive for DQB1*02, and 86.3% were positive for both alleles. The frequencies in relatives and controls were as follows: 70%, 90%, and 70%; and 56.6%, 45%, and 20%, respectively. In conclusion, we found that the proportion of our celiac patients carrying DQ2 was similar to the proportion of CD patients reported in populations with different genetic backgrounds. These results underline the primary importance of HLA-DQ alleles in susceptibility to celiac disease.

Plant defensins are antimicrobial peptides that exhibit mainly antifungal activity against a broad range of plant fungal pathogens. However, their actions against Candida albicans have not been extensively studied. The mRNA for gamma-thionin, a defensin from Capsicum chinense, has been expressed in bovine endothelial cells. The conditioned medium of these cells showed antifungal activity on germ tube formation (60-70% of inhibition) and on the viability of C. albicans (70-80% of inhibition). Additionally, C. albicans was not able to penetrate transfected cells. Conditioned medium from these cells also inhibited the viability (80%) of the human tumor cell line, HeLa.

Colletotrichum lindemuthianum was able to grow and produce extracellular cellulolytic activity in a defined medium containing cellulose as the main carbon substrate. As measured either by the hydrolysis of 4-methylumbelliferyl-beta-D -cellotrioside or the release of glucose from carboxymethylcellulose, activity reached a peak after 13 days of incubation and then declined whereas growth markedly increased afterwards. Detection of glucose in carboxymethylcellulose hydrolysates suggested the concerted operation of endo-1,4-beta-glucanase, cellobiohydrolase (exo-1,4-beta-glucanase) and beta-glucosidase activities. The highest levels of cellulolytic activity were obtained in media supplemented with cellulose and glutamate. Other carbon and nitrogen sources markedly influenced growth and enzyme production. Oligonucleotides homologous to specific regions of the cellobiohydrolase-encoding cbhII gene from Trichoderma reesei were used to isolate a C. lindemuthianum cbhII-DNA fragment whose sequence revealed homologies of 98% and 92% with the nucleotide and the deduced amino acid sequences of the corresponding cbhII-DNA of T. reesei, respectively. RT-PCR and Southern blot analyses of total RNA samples obtained from cellulose-grown but not from glucose-grown mycelium revealed the expression of the corresponding cbhII transcript. The cbhII-cDNA fragment was cloned and sequenced.

A major complication in 30% to 75% of cases of surgical treatment of alveolar cleft is resorption of the bone graft. A treatment alternative is the application of fibrin glue, which has the capacity to favor the integration of the graft. The main objective of the study was to evaluate if the use of the fibrin glue reduces bone resorption when it is applied locally. The authors designed a randomized clinical trial. Patients were divided into two groups: group 1, fibrin glue; and group 2, control. Pre- and postoperative graft volume, bone density, bone quality (Lekholm and Zarb, and Norton and Gamble classifications), and postoperative complications were evaluated. The follow-up for all patients was 3 months after discharge. Twenty-seven patients were surgically treated, 13 in group 1 and 14 in group 2. Group 1 had increased graft volume compared with group 2 (64.32 cm v 21.70 cm; P < 0.0001). Bone density was higher in group 1 than in group 2 (396.57 v 245.68; P > 0.076). Bone quality was type 1, 2 and 3 and 4 in group 1. Resorption in group 2 was 62.26%; in group 1, it was 29.72% (P > 0.081). The observed complications were infection and dehiscence of sutures (P > 0.537). The authors conclude that the fibrin glue significantly diminishes bone resorption, allowing improved graft integration and quality.

This work describes a novel plasmid encoding resistance to lincomycin in a staphylococcal isolate associated with mastitis infection from dairy cows. The cryptic plasmid pBMSa1 (2750 bp) of Staphylococcus aureus SA35 was subcloned and sequenced. Two ORFs (ORF1 and ORF2) were identified, and their putative transcription initiation and Shine-Dalgarno sequence were localized. ORF1 encodes a 334-residue protein almost identical to the putative Rep proteins of previously sequenced S. aureus rolling-circle-replicating plasmids. ORF2 encodes a 162-amino acid protein sharing a high degree of homology with LinA proteins (lincosamide O-nucleotidyltransferases) described in a variety of S. aureus strains. Intracellular single-stranded pBMSa1 DNA replicating intermediaries were detected, suggesting replication via the rolling-circle mechanism. A putative double-strand origin with significant homology to that of pC194 and a ssoA-type single-strand origin homologous sequence were also identified.

The author discusses his department's conversion to a new incident reporting system--why the decision was made, how the program was set up and data were entered, the purchase and installation of new computers, the computer network itself, the flow plan for reports, how training was conducted, and what problems had to be overcome.

The security problems faced by a recently opened psychiatric center located on the campus of a hospital--including staffing, fire safety, access control, patient restraints, and budget cuts--and how they are being dealt with.

Objective: The objective of this study was to perform an epidemiological analysis of the frequency of anophthalmia/microphthalmia (A/M) in syndromes identified in newborn infants in Spain., Patients and Methods: Data of the Spanish Collaborative Study of Congenital Malformations during the period of 1976-1994, corresponding to more than 1,200,000 births, was analyzed. Among these, 86 newborn infants with A/M presented some of the recognized syndromes., Results: There is a wide etiological heterogeneity among the syndromes with this ocular defect, with chromosomal syndromes being the most frequent (67.9% of total syndromes with A/M), followed by monogenic syndromes (19.1%), environmental (9.5%) and those of unknown etiology (3.6%)., Conclusions: Some guidelines when a baby is born with A/M are derived from this study. First, given the tendency of the defect to present together with other anomalies, it is advisable to perform a detailed study to rule out or to confirm the existence of other defects. Adequate samples should be taken (even in stillborn infants) for cytogenetic study. Examine carefully the prenatal history, looking for chronic diseases, infectious processes or exposure to teratogens. Depending on the baby's survival, follow-up of the psychomotor development should be made. All of these aspects are always important in malformed babies, but especially in infants with A/M given the tendency of the defect to present in syndromes as the etiologic diagnosis determines the counselling regarding the risk of recurrence, detection of carriers in some cases and possible prenatal diagnosis.

To evaluate the results of using and removing silicone oil in the management of giant retinal tears, 24 cases of vitrectomy with fluid-silicone oil exchange were reviewed. We did not use cryotherapy in any case. For chorioretinal adherence, we used either endolaser or postoperative external laser and a narrow buckle. The retina was reattached successfully in 22 (91.6%) of the 24 eyes. Of these, visual acuity was 20/200 or better in 18 (75%) eyes. This was significantly better than the preoperative visual acuity (P = .02). After removing the silicone oil in 15 cases, 13 (92.8%) had visual acuities of 20/200 or better, which was considerably better than that of the group in which the silicone oil was not removed (P = .006). We recommend removing the silicone oil and additional peeling of membranes an average of six months postoperatively when the eye is stable.

Refractive surgery has been used widely in some countries for the last 20 years for the correction of myopia. Radial keratotomy and keratomileusis, the most common procedures, may concur with retinal detachment. A total of 14 eyes in 12 patients, 7 after keratomileusis and 7 after radial keratotomy, which had either asymptomatic or symptomatic retinal breaks, subclinical and clinical rhegmatogenous retinal detachments, or both, are discussed here. Five eyes were treated with either laser photocoagulation or cryopexy alone, seven eyes with a scleral buckling procedure, one eye with vitrectomy, and one eye was not operated on. At the final follow-up examination, anatomic reattachment had been achieved in 12 of 14 eyes (85.7%). Visual acuity improved in 3 eyes (21.4%), remained stable in 9 eyes (64.3%), and was worse in 2 eyes (14.3%). The scleral buckling procedures used in the repair of retinal detachment induced refractive changes by modifying axial length and corneal curvature, with recurrence of myopia and astigmatism. Myopia increased a mean of -3.00 diopters in 6 of 7 eyes (86%). Myopic astigmatism power changed a mean of -1.00 diopter in 5 eyes (71%), and the astigmatic axes shifted in 3 eyes (43%). This situation could be prevented with an early peripheral search for and treatment of peripheral retinal degenerative pathologic changes, by avoiding encircling bucklings, or by using alternative methods of treatment.

We reviewed the medical records of 44 patients who underwent a pars plana vitrectomy to remove posttraumatic intraocular foreign bodies. The group most affected was that of males with a mean age of 28 years, who sustained a job injury, presenting with a single corneal laceration less than 2 mm in extension. There were 31 (70.45%) metallic foreign bodies. At surgery, 27 (61.36%) of the 44 foreign bodies were removed with forceps and 17 (38.63%) with the rare-earth magnet. From these patients, 84.61% obtained a final visual acuity equal or better than that on admission. We did not find a statistically significant difference between the groups with different timing on their vitrectomy, nor between groups presenting with and without vitreous hemorrhage.

pupae of Ceratitis capitata that were about to hatch were sterilized with Gamma(10 krds). Residual Malathionr was applied at 0.001, 0.01, 0.1, 1.0 and 10 micrograms/ml. A level of 0.0904 produced the highest mortality in females that reached sexual maturity and were irradiated as pupae (lowest for mature, non-irradiated males).