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Due to the specific action on bacterial cell wall, β-lactam antibiotics have gained widespread usage as they exhibit a high degree of specificity in targeting bacteria, but causing minimal toxicity to host cells. Under antibiotic pressure, bacteria may opt to shed their cell walls and transform into L-form state as a means to evade the antibiotic effects. In this study, we explored and identified diverse optimal conditions for both Gram-negative bacteria (E. coli DH5α (CTX)) and Gram-positive bacteria (B. subtilis ATCC6633), which were induced to L-form bacteria using lysozyme (0.5 ppm) and meropenem (64 ppm). Notably, when bacteria transformed into L-form state, both bacterial strains showed varying degrees of increased resistance to antibiotics polymyxin E, meropenem, rifampicin, and tetracycline. E. coli DH5α (CTX) exhibited the most significant enhancement in resistance to tetracycline, with a 128-fold increase, while B. subtilis ATCC6633 showed a 32-fold increase in resistance to tetracycline and polymyxin E. Furthermore, L-form bacteria maintained their normal metabolic activity, combined with enhanced oxidative stress, served as an adaptive strategy promoting the sustained survival of L-form bacteria. This study provided a theoretical basis for comprehending antibiotic resistance mechanisms, developing innovative treatment strategies, and confronting global antibiotic resistance challenges.

Bacterial cells are surrounded by a peptidoglycan (PG) wall, which is a crucial target for antibiotics. It is well known that treatment with cell wall-active antibiotics occasionally converts bacteria to a non-walled "L-form" state that requires the loss of cell wall integrity. L-forms may have an important role in antibiotic resistance and recurrent infection. Recent work has revealed that inhibition of de novo PG precursor synthesis efficiently induces the L-form conversion in a wide range of bacteria, but the molecular mechanisms remain poorly understood. Growth of walled bacteria requires the orderly expansion of the PG layer, which involves the concerted action not just of synthases but also degradative enzymes called autolysins. Most rod-shaped bacteria have two complementary systems for PG insertion, the Rod and aPBP systems. Bacillus subtilis has two major autolysins, called LytE and CwlO, which are thought to have partially redundant functions. We have dissected the functions of autolysins, relative to the Rod and aPBP systems, during the switch to L-form state. Our results suggest that when de novo PG precursor synthesis is inhibited, residual PG synthesis occurs specifically via the aPBP pathway, and that this is required for continued autolytic activity by LytE/CwlO, resulting in cell bulging and efficient L-form emergence. The failure of L-form generation in cells lacking aPBPs was rescued by enhancing the Rod system and in this case, emergence specifically required LytE but was not associated with cell bulging. Our results suggest that two distinct pathways of L-form emergence exist depending on whether PG synthesis is being supported by the aPBP or RodA PG synthases. This work provides new insights into mechanisms of L-form generation, and specialisation in the roles of essential autolysins in relation to the recently recognised dual PG synthetic systems of bacteria. [ABSTRACT FROM AUTHOR]

Mycoplasmas are bacteria that are extremely unstable in vitro as they lack a rigid cell wall. They are most often detected in association with other pathogens, including those that can become L-forms if treated with antibiotics. Mycoplasma colonies, as well as colonies of L-form bacteria, have a typical «fried egg» appearance, therefore it is necessary to differentiate them for the accurate diagnosis and choice of treatment. The paper presents data on mycoplasma infection diagnosis in cattle and results of differentiation of isolated mycoplasma and L-form bacteria colonies using multiple passaging and real-time polymerase chain reaction. For that, 177 samples were collected from animals with mycoplasmosis clinical signs, 45 of them were tested using molecular genetic method, 132 samples were subjected to bacteriological testing. Mycoplasma DNA was detected in 71.1% of samples, and specific colonies were detected in 3.8% of samples. Such biochemical tests of mycoplasma species identification as arginine hydrolysis, blood serum liquefaction, film and grain formation, inoculation into Tween-80-containing medium, hemadsorption and hemolysis of erythrocytes do not allow an objective assessment of the species belonging to mycoplasmas, but, according to the results obtained, the isolated species most likely belongs to Mycoplasma dispar, which is pathogenic for cattle. Real-time polymerase chain reaction is undoubtedly the most accurate and rapid diagnostic method for mycoplasmosis, but a preliminary diagnosis can also be established bacteriologically within 2–7 days. In addition, during microbiological testing, it is possible to assess the antibiotic resistance of mycoplasma isolates, thereby developing an optimal and high-quality scheme of the disease treatment and prevention.

Cell wall deficient "L- form" bacteria are of growing medical interest as a possible source of recurrent or persistent infection, largely because of their complete resistance to cell wall active antibiotics such as b-lactams. Antibiotics that specifically kill L-forms would be of potential interest as therapeutics, but also as reagents with which to explore the role of L-forms in models of recurrent infection. To look for specific anti-L-form antibiotics, we screened a library of several hundred FDA-approved drugs and identified compounds highly selective for L-form killing. Among the compounds identified were representatives of two different classes of calcium channel blockers: dihydropyridines, e.g., manidipine; and diphenylmethylpiperazine, e.g., flunarizine. Mode of action studies suggested that both classes of compound work by decreasing membrane fluidity. This leads to a previously recognized phenotype of L-forms in which the cells can continue to enlarge but fail to divide. We identified a considerable degree of variation in the activity of different representatives of the two classes of compounds, suggesting that it may be possible to modify them for use as drugs for L-form-dependent infections. [ABSTRACT FROM AUTHOR]

Bacterial cells are surrounded by a peptidoglycan (PG) wall, which is a crucial target for antibiotics. It is well known that treatment with cell wall-active antibiotics occasionally converts bacteria to a non-walled “L-form” state that requires the loss of cell wall integrity. L-forms may have an important role in antibiotic resistance and recurrent infection. Recent work has revealed that inhibition of de novo PG precursor synthesis efficiently induces the L-form conversion in a wide range of bacteria, but the molecular mechanisms remain poorly understood. Growth of walled bacteria requires the orderly expansion of the PG layer, which involves the concerted action not just of synthases but also degradative enzymes called autolysins. Most rod-shaped bacteria have two complementary systems for PG insertion, the Rod and aPBP systems. Bacillus subtilis has two major autolysins, called LytE and CwlO, which are thought to have partially redundant functions. We have dissected the functions of autolysins, relative to the Rod and aPBP systems, during the switch to L-form state. Our results suggest that when de novo PG precursor synthesis is inhibited, residual PG synthesis occurs specifically via the aPBP pathway, and that this is required for continued autolytic activity by LytE/CwlO, resulting in cell bulging and efficient L-form emergence. The failure of L-form generation in cells lacking aPBPs was rescued by enhancing the Rod system and in this case, emergence specifically required LytE but was not associated with cell bulging. Our results suggest that two distinct pathways of L-form emergence exist depending on whether PG synthesis is being supported by the aPBP or RodA PG synthases. This work provides new insights into mechanisms of L-form generation, and specialisation in the roles of essential autolysins in relation to the recently recognised dual PG synthetic systems of bacteria.

Cell wall deficient “L- form” bacteria are of growing medical interest as a possible source of recurrent or persistent infection, largely because of their complete resistance to cell wall active antibiotics such as β-lactams. Antibiotics that specifically kill L-forms would be of potential interest as therapeutics, but also as reagents with which to explore the role of L-forms in models of recurrent infection. To look for specific anti-L-form antibiotics, we screened a library of several hundred FDA-approved drugs and identified compounds highly selective for L-form killing. Among the compounds identified were representatives of two different classes of calcium channel blockers: dihydropyridines, e.g., manidipine; and diphenylmethylpiperazine, e.g., flunarizine. Mode of action studies suggested that both classes of compound work by decreasing membrane fluidity. This leads to a previously recognized phenotype of L-forms in which the cells can continue to enlarge but fail to divide. We identified a considerable degree of variation in the activity of different representatives of the two classes of compounds, suggesting that it may be possible to modify them for use as drugs for L-form-dependent infections.

Gut microbiota dysbiosis promotes metabolic syndromes (e.g., hypertension); however, the patterns that drive hypertensive pathology and could be targeted for therapeutic intervention are unclear. We hypothesized that gut microbes might translocate to the kidney to trigger hypertension. We aimed to uncover their method of colonization, and thereby how to maintain blood pressure homeostasis. Using combined approaches based on fluorescence in situ hybridization (FISH) and immunofluorescence staining, electron microscopy analysis, bacterial cultures, species identification, and RNA-sequencing-based meta-transcriptomics, we first demonstrated the presence of bacteria within the kidney of spontaneously hypertensive rats (SHRs) and its normotensive counterpart, Wistar-Kyoto rats (WKYs), and patients with hypertension. Translocated renal bacteria were coated with secretory IgA (sIgA) or remained dormant in the L-form. Klebsiella pneumoniae (K.pn) was identified in the kidneys of germ-free (GF) mice following intestinal transplantation, which suggested an influx of gut bacteria into the kidneys. Renal bacterial taxa and their function are associated with hypertension. Hypertensive hosts showed increased richness in the pathobionts of their kidneys, which were partly derived from the gastrointestinal tract. We also demonstrated the indispensable role of bacterial IgA proteases in the translocation of live microbes. Furthermore, Tartary buckwheat dietary intervention reduced blood pressure and modulated the core renal flora-host ecosystem to near-normal states. Taken together, the unique patterns of viable and dormant bacteria in the kidney provide insight into the pathogenesis of non-communicable chronic diseases and cardiometabolic diseases (e.g., hypertension), and may lead to potential novel microbiota-targeted dietary therapies.

[Display omitted] • L-forms were induced by lysozyme combined with meropenem. • The loss of the cell wall did not make bacteria less resistant to antibiotics. • L-form bacteria is not dormant subpopulation. • The division of L-forms is inhibited due to the block of the cell wall synthesis. • The stress response mechanism of bacteria helps the formation of L-form bacteria. Due to the specific action on bacterial cell wall, β-lactam antibiotics have gained widespread usage as they exhibit a high degree of specificity in targeting bacteria, but causing minimal toxicity to host cells. Under antibiotic pressure, bacteria may opt to shed their cell walls and transform into L-form state as a means to evade the antibiotic effects. In this study, we explored and identified diverse optimal conditions for both Gram-negative bacteria (E. coli DH5α (CTX)) and Gram-positive bacteria (B. subtilis ATCC6633), which were induced to L-form bacteria using lysozyme (0.5 ppm) and meropenem (64 ppm). Notably, when bacteria transformed into L-form state, both bacterial strains showed varying degrees of increased resistance to antibiotics polymyxin E, meropenem, rifampicin, and tetracycline. E. coli DH5α (CTX) exhibited the most significant enhancement in resistance to tetracycline, with a 128-fold increase, while B. subtilis ATCC6633 showed a 32-fold increase in resistance to tetracycline and polymyxin E. Furthermore, L-form bacteria maintained their normal metabolic activity, combined with enhanced oxidative stress, served as an adaptive strategy promoting the sustained survival of L-form bacteria. This study provided a theoretical basis for comprehending antibiotic resistance mechanisms, developing innovative treatment strategies, and confronting global antibiotic resistance challenges. [ABSTRACT FROM AUTHOR]

Almost all major classes of bacteria are surrounded by a peptidoglycan cell wall, which is a crucial target for antibiotics. It is now understood that many bacteria can tolerate loss of the cell wall provided that they are in an isotonic environment. Furthermore, in some cases the cells can continue to proliferate in a state known as the L-form. L-form proliferation occurs by an unusual blebbing or tubulation mechanism that is completely independent of the normally essential division machine or cell wall synthetic enzymes, and is resistant to cell wall-active antibiotics. However, the growth is limited by reactive oxygen species generated by the respiratory chain pathway. In this work, we examined the walled to L-form transition in a pathogenic Gram-negative bacterium, Streptobacillus moniliformis , which naturally lacks the respiratory chain pathway, under aerobic conditions. L-form-like cells often emerged spontaneously, but proliferation was not observed unless the cells were treated with cell wall-active antibiotics. Time-lapse imaging revealed that cell division of S. moniliformis L-forms involves unusual membrane dynamics with an apparent imbalance between outer membrane and cytoplasmic volume growth. The results suggest that outer membrane expansion may be an important general factor for L-form proliferation of diderm bacteria. [ABSTRACT FROM AUTHOR]

The rapid increase of circulating, antibiotic-resistant pathogens is a major ongoing global health crisis, and arguably, the end of the "golden age of antibiotics" is looming. This has led to a surge in research and development of alternative antimicrobials, including bacteriophages, to treat such infections (phage therapy). Isolating natural phage variants for the treatment of individual patients is an arduous and time-consuming task. Furthermore, the use of natural phages is frequently hampered by natural limitations, such as moderate in vivo activity, the rapid emergence of resistance, insufficient host range, or the presence of undesirable genetic elements within the phage genome. Targeted genetic editing of wild-type phages (phage engineering) has successfully been employed in the past to mitigate some of these pitfalls and to increase the therapeutic efficacy of the underlying phage variants. Clearly, there is a large potential for the development of novel, marker-less genome-editing methodologies to facilitate the engineering of therapeutic phages. Steady advances in synthetic biology have facilitated the in vitro assembly of modified phage genomes, which can be activated ("rebooted") upon transformation of a suitable host cell. However, this can prove challenging, especially in difficult-to-transform Gram-positive bacteria. In this chapter, we detail the production of cell wall-deficient L-form bacteria and their application to activate synthetic genomes of phages infecting Gram-positive host species., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Long non-coding RNAs (lncRNAs) have been proven to serve vital roles in various human diseases. However, their involvement in the development of pleomorphic adenoma (PA) in the salivary gland has yet to be examined. In the present study, microarray analysis of the lncRNA and mRNA expression profiles in pleomorphic adenoma gene 1 (PLAG1) transgenic mice was performed. Next, bioinformatics tools were used to predict the differentially expressed genes associated with PA, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and lncRNA-mRNA co-expression network analyses. Comparison of the transgenic and control mice demonstrated that a total of 9,110 lncRNAs and 7,750 mRNAs were significantly differentially expressed (fold change >2; P<0.05). Subsequently, six lncRNAs were randomly selected for further analysis, and five of these were validated as differentially expressed in PA by quantitative polymerase chain reaction, supporting the methodology employed in the current study. The GO and KEGG enrichment analysis of the differentially expressed mRNAs revealed that these mRNAs were closely associated with a number of processes involved in the development of PA. Furthermore, the lncRNA-mRNA co-expression network indicated that certain lncRNAs may serve vital roles in the pathogenesis of PA by interacting with a number of core genes. Taken together, these results indicated that lncRNAs and mRNAs were differentially expressed in PA tissues obtained from PLAG1 transgenic mice as compared with those from control mice. These differentially expressed lncRNAs may act as novel biomarkers and therapeutic targets for PA. [ABSTRACT FROM AUTHOR]

Background Anaplastic pleomorphic xanthoastrocytoma (PXA) was added to grade III glial tumors as a distinct entity in the 2016 World Health Organization (WHO) classification of tumors of the central nervous system. We retrospectively reviewed and analyzed 55 pathologically confirmed PXA cases according to the newest WHO classification to better clarify the clinical, molecular, and prognostic features of this rare neoplasm. Methods In total, 55 pathologically confirmed PXA cases according to the newest WHO classification were retrospectively reviewed and analyzed. After sequencing for BRAF, TERT, IDH1/2, and H3F3A, survival analysis was performed to determine the factors affecting survival. Results The patients with BRAF V600E mutations were generally younger than those without it, although not statistically significant (27.9 ± 15.4 years and 37.1 ± 17.0 years, respectively, P = 0.054). TERT promoter mutation frequency in PXA was lower than in patients with anaplastic PXA although not statistically significant (4.4% and 28.6%, P = 0.083). One instance of PXA with IDH2 mutation, and no IDH1 and H3F3A mutations were found. In terms of prognosis, patients with anaplastic PXA had shorter overall survival and progression-free survival compared with patients with PXA. The subgroup with gross total resection had a longer median OS (not reached vs. 60.0 months, P = 0.0221) and PFS (not reached vs. 60.0 months, P = 0.0232) compared with patients with PXA with subtotal resection. Conclusions The identification of BRAF V600E, TERT, and IDH2 mutations in PXA expands our molecular understanding of PXA. Patients with PXA with gross total resection achieve good outcomes. Highlights • The patients with BRAF V600E mutations were generally younger than those without it. • TERT promoter mutation frequency in patients with PXA was lower than in those with anaplastic PXA. • Patients with PXA with gross total resection have a better survival prognosis. [ABSTRACT FROM AUTHOR]

Musical hallucinations are a relatively rare form of auditory hallucination characterized by hearing of music in the absence of any external stimuli. This phenomenon has been linked to both psychiatric and structural lesions. We present the case of a previously healthy young male whose presentation with musical hallucinations led to the diagnosis of a rare tumour, anaplastic pleomorphic xanthoastrocytoma. [ABSTRACT FROM AUTHOR]

This work aims to enhance the bioproduction of xanthan gum by screening a hyper-yield producer from the wild-type Xanthomonas campestris during a long-term continuous subculture. We reported a cell-wall deficient mutant, which performed a shift of cell morphology from rod-shaped to round-shaped. Both the yield of xanthan gum and the conversion rate of feedstock were assessed using sucrose as a carbon source with the supplement of yeast extract powder, L-glutamic acid, and other raw materials. After 96 h aerobic fermentation, the yield of xanthan gum of the mutant reached up to 32 g/L, which was 3.4 times of that of the wild-type strain. The conversion rate of feedstock in the mutant was up to 92.1%, which was 3 times of that of the wild-type (31.2%). Furthermore, pigments generated were determined and compared. As a result, the fermentation broth of the wild-type performed an OD560nm of 0.296, which was 5.8 times of that (OD560nm = 0.051) of the mutant. Microscopy analysis showed that the percentage of free-living cells in broth affected the color of the final product. Moreover, the robustness of the fermentation performance of the cell-wall deficient mutant at a pilot scale showed potential for industrial application. [ABSTRACT FROM AUTHOR]

Abstract Certain pleomorphic archaeal viruses are highly infectious even at saturated salt. These viruses belong to the genus Betapleolipovirus of the recently described archaeal virus family Pleolipoviridae. Pleolipoviruses comprise single-stranded or double-stranded, circular or linear DNA genomes that share countless homologues among various archaeal genetic elements. Here we describe a new extremely halophilic betapleolipovirus, Halorubrum pleomorphic virus 9 (HRPV9), which has an integrase gene. We also identified new genes encoding minor pleolipoviral structural proteins. The studies on HRPV9 enhance our knowledge on pleolipoviruses, especially their reciprocal relatedness and relation to certain archaeal plasmids, proviruses and membrane vesicles. [ABSTRACT FROM AUTHOR]

Myxofibrosarcoma (MFS) and undifferentiated pleomorphic sarcoma (UPS) frequently display infiltrative growth into the adjacent normal soft tissue. In this study, we aimed to determine whether the microscopic extension into surrounding normal tissue can influence the local recurrence of MFS and UPS. A total of 42 cases (22 MFS and 20 UPS) were examined. The length of the microscopic extension was measured from the edge of the main tumor mass to the end of infiltration. The length of 5.5 mm was selected as the optimal cut‐off value that could predict local recurrence using the receiver operating characteristic (ROC) curve and Youden index. Longer length of microscopic extension was significantly correlated with the status of resection margin (P = 0.032). The group with longer length of microscopic extension (>5.5 mm) had significantly worse recurrence‐free survival than the group with shorter length of microscopic extension (≤5.5 mm) (P = 0.000). Multivariate analysis revealed that the length of microscopic extension was independent predictors of recurrence‐free survival (P = 0.018). In conclusion, microscopic extensions at the edge of the main mass into the surrounding normal tissue were observed in most MFS and UPS patients, and the length of microscopic extension was associated with local recurrence. [ABSTRACT FROM AUTHOR]

Codominant marker systems are better suited to analyze population structure and assess the source of an individual in admixture analyses. Currently, there is no codominant marker system using microsatellites developed for the sea sandwort, Honckenya peploides (L.) Ehrh., an early colonizer in island systems. We developed and characterized novel microsatellite loci from H. peploides, using reads collected from whole genome shotgun sequencing on a 454 platform. The combined output from two shotgun runs yielded a total of 62,669 reads, from which 58 loci were screened. We identified 12 polymorphic loci that amplified reliably and exhibited disomic inheritance. Microsatellite data were collected and characterized for the 12 polymorphic loci in two Alaskan populations of H. peploides: Fossil Beach, Kodiak Island (n = 32) and Egg Bay, Atka Island (n = 29). The Atka population exhibited a slightly higher average number of alleles (3.9) and observed heterozygosity (0.483) than the Kodiak population (3.3 and 0.347, respectively). The overall probability of identity values for both populations was PID = 2.892e−6 and PIDsib = 3.361e−3. We also screened the 12 polymorphic loci in Wilhelmsia physodes (Fisch. ex Ser.) McNeill, the most closely related species to H. peploides, and only one locus was polymorphic. These microsatellite markers will allow future investigations into population genetic and colonization patterns of the beach dune ruderal H. peploides on new and recently disturbed islands. [ABSTRACT FROM AUTHOR]

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Abstract: Pleomorphic xanthoastrocytoma (PXA) is a rare localized glioma characterized by frequent BRAF V600E mutation and CDKN2A/B deletion. We explored the association of copy‐number variants (CNVs) with BRAF mutations, tumor grade, and patient survival in a cohort of 41 PXA patients using OncoScan chromosomal microarray. Primary resection specimens were available in 38 cases, including 24 PXA and 14 anaplastic PXA (A‐PXA), 23 BRAF V600E mutant tumors (61%). CNVs were identified in all cases and most frequently involved chromosome 9 with homozygous CDKN2A/B deletion (n = 33, 87%), a higher proportion than previously detected by comparative genomic hybridization (50%–60%) (37). CDKN2A/B deletion was present in similar proportion of PXA (83%), A‐PXA (93%), BRAF V600E (87%), and wild‐type (87%) tumors. Whole chromosome gains/losses were frequent, including gains +7 (n = 15), +2 (n = 11), +5 (n = 10), +21 (n = 10), +20 (n = 9), +12 (n = 8), +15 (n = 8), and losses −22 (n = 11), −14 (n = 7), −13 (n = 5). Losses and copy‐neutral loss of heterozygosity were significantly more common in A‐PXA, involving chromosomes 22 (P = 0.009) and 14 (P = 0.03). Amplification of 8p and 12q was identified in a single tumor. Histologic grade was a robust predictor of overall survival (P = 0.003), while other copy‐number changes, including CDKN2A/B deletion, did not show significant association with survival. Distinct histologic patterns of anaplasia included increased mitotic activity in an otherwise classic PXA or associated with small cell, fibrillary, or epithelioid morphology, with loss of SMARCB1 expression in one case. In 10 cases, matched specimens were compared, including A‐PXA with areas of distinct low‐ and high‐grade morphology (n = 2), matched primary/tumor recurrence (n = 7), or both (n = 1). Copy‐number changes on recurrence/anaplastic transformation were complex and highly variable, from nearly identical profiles to numerous copy‐number changes. Overall, we confirm CDKN2A/B deletion as key a feature of PXA not associated with tumor grade or BRAF mutation, but central to the underlying genetics of PXA. [ABSTRACT FROM AUTHOR]

ALK rearrangements occur in up to 10% of spitzoid melanocytic neoplasms. No reported cases have shown homozygous deletion of 9p21 (CDKN2A) or gains of 6p25 (RREB1) or 11q13 (CCND1), which have been associated with aggressive clinical behavior. Here we report 2 unique cases. Case 1 occurred in a 9‐year‐old male with a 14‐mm nodule on the anterior left thigh. Biopsy revealed an ALK‐positive Spitz tumor containing an irregular nodule of densely packed melanocytes with increased mitoses and loss of p16 immunoreactivity. FISH analysis showed homozygous deletion of 9p21 and gain of 6p25. Sentinel lymph node biopsy revealed small subcapsular foci of tumor. Case 2 occurred in a 7‐year‐old female with a 12‐mm nodule on the anterior right ankle. Biopsy revealed an ALK‐positive Spitz tumor containing an expansile nodule of pleomorphic epithelioid melanocytes with numerous mitoses and loss of p16 immunoreactivity. By FISH, the nodule showed homozygous deletion of 9p21 and gains of 6p25 and 11q13. Our cases show the transformation of tumors produced by an activating kinase fusion gene (ALK) through secondary genetic changes including loss of tumor suppressor activity (CDKN2A). Long‐term follow up will be important to further define the behavior of these unique Spitz tumors. [ABSTRACT FROM AUTHOR]

Engineered bacteriophages provide powerful tools for biotechnology, diagnostics, pathogen control, and therapy. However, current techniques for phage editing are experimentally challenging and limited to few phages and host organisms. Viruses that target Gram-positive bacteria are particularly difficult to modify. Here, we present a platform technology that enables rapid, accurate, and selection-free construction of synthetic, tailor-made phages that infect Gram-positive bacteria. To this end, custom-designed, synthetic phage genomes were assembled in vitro from smaller DNA fragments. We show that replicating, cell wall-deficient Listeria monocytogenes L-form bacteria can reboot synthetic phage genomes upon transfection, i.e., produce virus particles from naked, synthetic DNA. Surprisingly, Listeria L-form cells not only support rebooting of native and synthetic Listeria phage genomes but also enable cross-genus reactivation of Bacillus and Staphylococcus phages from their DNA, thereby broadening the approach to phages that infect other important Gram-positive pathogens. We then used this platform to generate virulent phages by targeted modification of temperate phage genomes and demonstrated their superior killing efficacy. These synthetic, virulent phages were further armed by incorporation of enzybiotics into their genomes as a genetic payload, which allowed targeting of phage-resistant bystander cells. In conclusion, this straightforward and robust synthetic biology approach redefines the possibilities for the development of improved and completely new phage applications, including phage therapy. [ABSTRACT FROM AUTHOR]

During the development of single particle cryo-EM in past five decades, icosahedral viruses have led the resolution progress owing to their large mass and high symmetry. Many technical advances in cryo-EM were first established with viruses. Since reaching ∼4 Å resolution in 2008, it has become a relatively routine task to solve the atomic structure of isolated viruses. The future of structural virology will be increasingly focused on remaining challenges including solving structures of jumbo viruses, intermediate functional states during assembly, maturation, and infection, and in situ structures. Recent demonstrations of near-atomic resolution structure with electron tomography and sub-tomogram averaging opens a new direction for high resolution studies of pleomorphic viruses and the pleomorphic states of icosahedral viruses that have defied past efforts using the single particle cryo-EM approach. [ABSTRACT FROM AUTHOR]

Background: The lesser grain borer Rhyzopertha dominica (Coleoptera: Bostrichidae) is a stored-product pest beetle. Early histological studies dating back to 1930s have reported that R. dominica and other bostrichid species possess a pair of oval symbiotic organs, called the bacteriomes, in which the cytoplasm is densely populated by pleomorphic symbiotic bacteria of peculiar rosette-like shape. However, the microbiological nature of the symbiont has remained elusive. Results: Here we investigated the bacterial symbiont of R. dominica using modern molecular, histological, and microscopic techniques. Whole-mount fluorescence in situ hybridization specifically targeting symbiotic bacteria consistently detected paired bacteriomes, in which the cytoplasm was full of pleomorphic bacterial cells, in the abdomen of adults, pupae and larvae, confirming previous histological descriptions. Molecular phylogenetic analysis identified the symbiont as a member of the Bacteroidetes, in which the symbiont constituted a distinct bacterial lineage allied to a variety of insect-associated endosymbiont clades, including Uzinura of diaspidid scales, Walczuchella of giant scales, Brownia of root mealybugs, Sulcia of diverse hemipterans, and Blattabacterium of roaches. The symbiont gene exhibited markedly AT-biased nucleotide composition and significantly accelerated molecular evolution, suggesting degenerative evolution of the symbiont genome. The symbiotic bacteria were detected in oocytes and embryos, confirming continuous host-symbiont association and vertical symbiont transmission in the host life cycle. Conclusions: We demonstrate that the symbiont of R. dominica constitutes a novel bacterial lineage in the Bacteroidetes. We propose that reductive evolution of the symbiont genome may be relevant to the amorphous morphology of the bacterial cells via disruption of genes involved in cell wall synthesis and cell division. Genomic and functional aspects of the host-symbiont relationship deserve future studies. [ABSTRACT FROM AUTHOR]

Particle-associated bacteria (PAB) and free-living bacteria (FLB) from aquatic environments during phytoplankton blooms differ in their physical distance from algae. Both the interactions within PAB and FLB community fractions and their relationship with the surrounding environmental properties are largely unknown. Here, by using high-throughput sequencing and network-based analyses, we compared the community and network characteristics of PAB and FLB from a plateau lake during a Microcystis aeruginosa bloom. Results showed that PAB and FLB differed significantly in diversity, structure and microbial connecting network. PAB communities were characterized by highly similar bacterial community structure in different sites, tighter network connections, important topological roles for the bloom-causing M. aeruginosa and Alphaproteobacteria, especially for the potentially nitrogen-fixing (Pleomorphomonas) and algicidal bacteria (Brevundimonas sp.). FLB communities were sensitive to the detected environmental factors and were characterized by significantly higher bacterial diversity, less connectivity, larger network size and marginal role of M. aeruginosa. In both networks, covariation among bacterial taxa was extensive (>88% positive connections), and bacteria potentially affiliated with biogeochemical cycling of nitrogen (i.e., denitrification, nitrogen-fixation and nitrite-oxidization) were important in occupying module hubs, such as Meganema, Pleomorphomonas, and Nitrospira. These findings highlight the importance of considering microbial network interactions for the understanding of blooms. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate and compare the immunoexpression of glucose transporter-1 (GLUT-1) and angiogenic index between pleomorphic adenomas (PAs), adenoid cystic carcinomas (ACCs), and mucoepidermoid carcinomas (MECs) of the salivary glands, and establish associations with the respective subtype/histological grade. Twenty PAs, 20 ACCs, and 10 MECs were submitted to morphological and immunohistochemical analysis. GLUT-1 expression was semi-quantitatively evaluated and angiogenic index was assessed by microvessel counts using anti-CD34 antibody. Higher GLUT-1 immunoexpression was observed in the MECs compared to PAs and ACCs ( p = 0.022). Mean number of microvessels was 66.5 in MECs, 40.4 in PAs, and 21.2 in ACCs ( p < 0.001). GLUT-1 expression and angiogenic index showed no significant correlation in the tumors studied. Results suggest that differences in biological behavior of the studied tumors are related to GLUT-1. Benign and malignant salivary gland tumors differ in the angiogenic index; however, angiogenesis may be independent of the tumor cell's metabolic demand. [ABSTRACT FROM AUTHOR]

The peptidoglycan (PG) cell wall is a defining feature of the bacteria. It emerged very early in evolution and must have contributed significantly to the success of these organisms. The wall features prominently in our thinking about bacterial cell function, and its synthesis involves the action of several dozen proteins that are normally essential for viability. Surprisingly, it turns out to be relatively simple to generate bacterial genetic variants called L-forms that completely lack PG. They grow robustly provided that lack of the cell wall is compensated for by an osmoprotective growth medium. Although their existence has been noted and studied on and off for many decades, it is only recently that modern molecular and cellular methods have been applied to L-forms. We used Bacillus subtilis as an experimental model to understand the molecular basis for the L-form switch. Key findings included the discovery that L-forms use an unusual blebbing, or tubulation and scission mechanism to proliferate. This mechanism is completely independent of the normal FtsZ-based division machinery and seems to require only an increased rate of membrane synthesis, leading to an increased surface area-to-volume ratio. Antibiotics that block cell wall precursor synthesis, such as phosphomycin, efficiently induce the L-form switch without the need for genetic change. The same antibiotics turned out to induce a similar L-form switch in a wide range of bacteria, including Escherichia coli, in which we showed that proliferation was again FtsZ-independent. Aside from further basic science, future work on L-forms is likely to focus on their possible role in chronic or recurrent infections, their use as a model in studies of the origins of life, and possibly, biotechnological applications. [ABSTRACT FROM AUTHOR]

We describe a distinctive renal tumor, a myolipoosteoma (MLO), in an 11-year-old boy who presented with a 6-month history of slight right flank intermittent pain. A gross examination revealed a welldefined, 5.5 cm mass with bone-like consistency. The lesion histologically featured an admixture of mature adipose tissue, spindle cells, and bony components. No atypia, mitotic activity, or pleomorphisms were observed in the tumor. The spindle cells were smooth muscle actin (SMA) and desmin positive but HMB45 and Melan-A negative, indicating that they were of a muscular nature and differed from that of angiomyolipoma (AML). The patient had no evidence of recurrence or metastasis 56 months postoperatively. We speculate that the present tumor, which to the best of our knowledge differs from all previously described tumors, is of nephrogenic rest (NR) origin and has a favorable prognosis. [ABSTRACT FROM AUTHOR]

Neurocysticercosis (NCC) is the most common parasitic disease of the human central nervous system (CNS), a pleomorphic disease with a diverse array of clinical manifestations. The infection is pleomorphic and dependent on a complex range of interconnecting factors, including number and size of the cysticerci, their stage of development and localisation within the brain with resulting difficulties in accurate diagnosis and staging of the disease. This review examines the factors that contribute to the accurate assessment of NCC distribution and transmission that are critical to achieving robust disease burden calculations. Control and prevention of T. solium transmission should be a key priority in global health as intervention can reduce the substantial healthcare and economic burdens inflicted by both NCC and taeniasis. Surveillance systems need to be better established, including implementing obligatory notification of cases. In the absence of reliable estimates of its global burden, NCC will remain-along with other endemic zoonoses, of low priority in the eyes of funding agencies–a truly neglected disease. [ABSTRACT FROM AUTHOR]

Context: The salivary glands are the site of origin of a wide variety of neoplasms and are also relatively uncommon. The histopathology of these tumors is said to be the most complex and diverse of any organ in the body. The incidence of salivary gland tumors (SGTs) is claimed to be influenced by geographical and racial factors. Histopathological diagnosis plays a major role in the diagnosis of these neoplasms, with very few contribution using special stains, immunohistochemistry and cytogenetic studies. Aims: Aimed at understanding the epidemiological pattern of these tumors and to compare our findings with reports done elsewhere. Settings and Design: This is a retrospective study done at Pathology Department a Postgraduate Teaching Hospital, Tertiary Care Centre in Bagalkot, Karnataka, India. All the cases of SGTs, which had been recorded in a 3-year period from 2009 to 2012, were enrolled in the study. Subjects and Methods: Clinical data were recorded and analyzed with respect to gender, age, site and histopathologic type. Results: Data of 59 cases of SGTs were recorded, of which 43 (69.16%) cases were classified as benign tumors and 16 (22.39%) cases as malignant tumors. Male to female ratio (M/F) and the mean age of patients were 1:1.8 and 43 years, respectively. Pleomorphic adenoma (60.71%) and adenoid cystic carcinoma (14.94%) were the most common benign and malignant neoplasms. Conclusions: Although the SGTs encountered were similar in most of their characteristics to those reported in India and other countries, some differences such as relative frequency, age and gender prevalence were discovered. [ABSTRACT FROM AUTHOR]

Key message : Potato StCYP86A33 complements the Arabidopsis AtCYP86A1 mutant, horst - 1. Abstract: Suberin is a cell-wall polymer that comprises both phenolic and aliphatic components found in specialized plant cells. Aliphatic suberin is characterized by bi-functional fatty acids, typically ω-hydroxy fatty acids and α,ω-dioic acids, which are linked via glycerol to form a three-dimensional polymer network. In potato ( Solanum tuberosum L.), over 65 % of aliphatics are either ω-hydroxy fatty acids or α,ω-dioic acids. Since the biosynthesis of α,ω-dioic acids proceeds sequentially through ω-hydroxy fatty acids, the formation of ω-hydroxy fatty acids represents a significant metabolic commitment during suberin deposition. Four different plant cytochrome P450 subfamilies catalyze ω-hydroxylation, namely, 86A, 86B, 94A, and 704B; though to date, only a few members have been functionally characterized. In potato, CYP86A33 has been identified and implicated in suberin biosynthesis through reverse genetics (RNAi); however, attempts to express the CYP86A33 protein and characterize its catalytic function have been unsuccessful. Herein, we describe eight fatty acid ω-hydroxylase genes (three CYP86As, one CYP86B, three CYP94As, and a CYP704B) from potato and demonstrate their tissue expression. We also complement the Arabidopsis cyp86A1 mutant horst- 1 using StCYP86A33 under the control of the Arabidopsis AtCYP86A1 promoter. Furthermore, we provide preliminary analysis of the StCYP86A33 promoter using a hairy root transformation system to monitor pStCYP86A33::GUS expression constructs. These data confirm the functional role of StCYP86A33 as a fatty acid ω-hydroxylase, and demonstrate the utility of hairy roots in the study of root-specific genes. [ABSTRACT FROM AUTHOR]

Pleomorphic adenoma is the most common benign tumor of the salivary gland. Pleomorphic adenoma occurs most commonly in the parotid gland but it may involve other salivary gland such as submandible or lingual. We report an ectopic pleomorphic adenoma in the subcutaneous layer of the face. A woman presented with a mass of the nasolabial fold. After excision of the mass, it was revealed as an pleomorphic adenoma pathologically. An ectopic pleomorphic adenoma which was located in the subcutaneous layer of the face is very rare in medical literature. [ABSTRACT FROM AUTHOR]

Relata-se inusitado achado de micro-organismos, semelhantes às espiroquetas, móveis e de diferentes morfologias e tamanhos, identificados pela microscopia de campo escuro, no sangue de animais do Centro de Bioterismo da Faculdade de Medicina da USP. As bactérias não crescem em meios habituais de cultivo, são pouco coradas pelo Giemsa e derivados da prata, e as provas sorológicas e moleculares foram negativas para Borrelia e Leptospira. A microscopia eletrônica revelou presença de micro-organismos com morfologia de Mycoplasma e, devido à sua mobilidade, sugeriu-se a presença de Mollicutes do gênero Spiroplasma. Visualizaram-se micro-organismos com mesmas características em 15 dos 26 funcionários (57,6%) do Centro de Bioterismo da FMUSP; contudo, exames clínicos e laboratoriais indicaram que os indivíduos estavam saudáveis. Estudos adicionais desenvolvidos na Disciplina de Reumatologia da FMUSP mostraram que, aproximadamente, 94% dos pacientes com Síndrome Baggio-Yoshinari (SBY) e 20% dos indivíduos normais também exibiam as mesmas estruturas identificadas no Centro de Bioterismo. A microscopia eletrônica realizada com amostras de pacientes com SBY mostrou bactérias que apresentam semelhanças com Mycoplasma, Chlamydia e Bacteroides. Visto que as sorologias e os testes moleculares foram negativos para estes contaminantes e com base em publicações da literatura médica, sugeriu-se que estes agentes infecciosos latentes fossem bactérias na sua apresentação L, que são definidas como bactérias despojadas de parede celular, assumindo, assim, morfologia de Mycoplasma, sendo, na maioria dos casos, inofensivas aos hospedeiros. Concluímos que os "espiroquetídeos" visualizados em animais e funcionários do Centro de Bioterismo seriam bactérias na forma L, não patogênicas, provenientes de contaminantes do meio ambiente, infecções regulares habituais ou oriundos de micro-organismos endógenos da flora saprofítica normal. Ao contrário, os "espiroquetídeos" identificados na SBY, ao preservarem a capacidade de invadir células in vitro, são potencialmente patogênicos e relacionados com a etiologia da SBY. Interpretamos a SBY como zoonose nova e particular ao território brasileiro, causada por espiroquetas adaptadas às formas latentes, possivelmente provenientes de mutações bacterianas em resposta às condições ecológicas e geográficas próprias do país.We report the unusual finding of mobile spirochetal microorganisms with different morphologies and sizes, on dark-field microscopy of the blood of animals from the Vivarium of the Medical School of USP. The bacteria did not grow in common culture media, shows faint staining to Giemsa and silver-derived stains, and serologies and molecular tests were negative for Borrelia and Leptospira. Electron microscopy revealed the presence of microorganisms with Mycoplasma-like morphology and, due to its mobility, it was suggested that they represented Mollicutes of the genus Spiroplasma. Microorganisms with the same morphology were also observed in 15 out of 26 employees (57.6%) of the Vivarium of FMUSP; however, clinical and laboratorial exams indicated that those individuals were healthy. Additional studies undertaken at the Rheumatology Department of FMUSP demonstrated the presence of the same structures identified at the Vivarium in approximately 94% of the patients with Baggio-Yoshinary syndrome (BYS) and 20% of healthy individuals. Electron microscopy of the blood of BYS patients showed bacteria that shared similarities with Mycoplasma, Chlamydia, and Bacteroides. Since serologies and molecular tests were negative for those contaminants, and based on publications in the medical literature, it was suggested that those latent infectious agents were L-form bacteria, defined as cell wall deficient bacteria, assuming, therefore, Mycoplasma morphology and they are, for the most part, harmless to the host. We concluded that spirochetal microorganisms visualized in animals and employees of the Vivarium were non-pathogenic L-form bacteria from contaminants in the environment, regular infections, or endogenous microorganism from the normal saprophytic flora. On the other hand, spirochetal organisms identified in BYS, by preserving the capacity to invade cells in vitro, are potentially pathogenic and related to the etiology of BYS. We consider BYS as a novel Brazilian zoonosis caused by spirochetes adapted to their latent form, possibly due to bacterial mutations in response to ecologic and geographic conditions unique to Brazil.

Background: The authors hypothesized that histogenetic classification of salivary duct carcinoma (SDC) could account for de novo tumors and those with morphologic or molecular evidence (pleomorphic adenoma gene 1 [PLAG1], high-mobility group AT hook 2 [HMGA2] rearrangement, amplification) of pleomorphic adenoma (PA).Methods: SDCs (n = 66) were reviewed for morphologic evidence of PA. PLAG1 and HMGA2 alterations were detected by fluorescence in situ hybridization (FISH). PLAG1-positive tumors were tested by FISH for fibroblast growth factor receptor 1 (FGFR1) rearrangement. Thirty-nine tumors were analyzed using a commercial panel for mutations and copy number variations in 50 cancer-related genes.Results: On the basis of combined morphologic and molecular evidence of PA, 4 subsets of SDC emerged: 1) carcinomas with morphologic evidence of PA but intact PLAG1 and HMGA2 (n = 22); 2) carcinomas with PLAG1 alteration (n = 18) or 3) HMGA2 alteration (n = 12); and 4) de novo carcinomas, without morphologic or molecular evidence of PA (n = 14). The median disease-free survival was 37 months (95% confidence interval, 28.4-45.6 months). Disease-free survival and other clinicopathologic parameters did not differ for the subsets defined above. Combined Harvey rat sarcoma viral oncogene homolog/phosphatidylinositol-4,5-biphosphate 3-kinase, catalytic subunit α (HRAS/PIK3CA) mutations were observed predominantly in de novo carcinomas (5 of 8 vs 2 of 31 tumors; P = .035). Erb-B2 receptor tyrosine kinase 2 (ERBB2) copy number gain was not observed in de novo carcinomas (0 of 8 vs 12 of 31 tumors; P = .08). Tumor protein 53 (TP53) mutations were more common in SDC ex pleomorphic adenomas than in de novo carcinomas (17 of 31 vs 1 of 8 tumors; P = .033).Conclusions: The genetic profile of SDC varies with the absence or presence of pre-existing PA and its cytogenetic signature. Most de novo SDCs harbor combined HRAS/PIK3CA mutations and no ERBB2 amplification. Cancer 2016;122:3136-44. © 2016 American Cancer Society. [ABSTRACT FROM AUTHOR]

Background: In cancers of prostate, breast, oropharynx, lung, hypopharynx and skin, human tissue kallikreins has been demonstrated as a main role in these problems. There are many research works in which some human tissue kallikreins are expressed in salivary glands. In the present study, the main goal was to determine expression of human tissue kallikreins 4, 8, 10, 11 and 13 in pleomorphic adenomas and mucoepidermoid carcinomas. Methods: Sixty-six specimens (45 cases of pleomorphic adenomas and 21 cases mucoepidermoid carcinomas) were selected for final analysis by immunohistochemistry. For doing association test, clinical parameters obtained from the patients' medical charts, which included age, gender were used and the nonparametric tests employed for statistical analyses. Results: The expression of human kallikreins 4, 8, 11 and 13 was more prominent in benign and malignant tumors compared to that in normal tissues and the difference was significant. In addition, the expression of human kallikreins 4, 8, 10 and 11 in malignant tumors was more than that in benign tumors, with statistically significant differences. Conclusion: The differences in the levels of human kallikreins 4, 8, 11 and 13 suggest that kallikreins may benefit in determining tumor behavior of salivary gland tumors. [ABSTRACT FROM AUTHOR]

* Background and aims Plants are able to grow under phosphorus (P)-deficient conditions by coordinating Pi acquisition, translocation from roots to shoots and remobilization within the plant. Previous reports have demonstrated that cell-wall pectin contributes greatly to rice cell-wall Pi re-utilization under P-deficient conditions, but whether other factors such as ethylene also affect the pectin-remobilizing capacity remains unclear. * Methods Two rice cultivars, 'Nipponbare' (Nip) and 'Kasalath' (Kas) were cultured in the þP (complete nutrient solution), -P (withdrawing P from the complete nutrient solution), þPþACC (1-amino-cyclopropane-1-carboxylic acid, an ethylene precursor, adding 1 µM ACC to the complete nutrient solution) and -PþACC (adding 1 µM ACC to -P nutrient solution) nutrient solutions for 7 d. * Key Results After 7 d -P treatment, there was clearly more soluble P in Nip root and shoot, accompanied by additional production of ethylene in Nip root compared with Kas. Under P-deficient conditions, addition of ACC significantly increased the cell-wall pectin content and decreased cell-wall retained P, and thus more soluble P was released to the root and translocated to the shoot, which was mediated by the expression of the P deficiency-responsive gene OsPT2, which also strongly induced by ACC treatment under both P-sufficient and P-deficient conditions. * Conclusions Ethylene positively regulates pectin content and expression of OsPT2, which ultimately makes more P available by facilitating the solubilization of P fixed in the cell wall and its translocation to the shoot. [ABSTRACT FROM AUTHOR]

Background: Compression wood (CW) forms on the underside of tilted stems of coniferous gymnosperms and opposite wood (OW) on the upperside. The tracheid walls of these wood types differ structurally and chemically. Although much is known about the most severe form of CW, severe CW (SCW), mild CWs (MCWs), also occur, but less is known about them. In this study, tracheid wall structures and compositions of two grades of MCWs (1 and 2) and SCW were investigated and compared with OW in slightly tilted radiata pine (Pinus radiata) stems. Results: The four wood types were identified by the distribution of lignin in their tracheid walls. Only the tracheid walls of OW and MCW1 had a S3 layer and this was thin in MCW1. The tracheid walls of only SCW had a S2 layer with helical cavities in the inner region (S2i). Using immunomicroscopy, (1→4)-β-D-galactans and (1→3)-β-D-glucans were detected in the tracheid walls of all CWs, but in only trace amounts in OW. The (1→4)-β-D-galactans were located in the outer region of the S2 layer, whereas the (1→3)-β-D-glucans were in the inner S2i region. The areas and intensities of labelling increased with CW severity. The antibody for (1→4)-β-D-galactans was also used to identify the locations and relative amounts of these galactans in whole stem cross sections based on the formation of an insoluble dye. Areas containing the four wood types were clearly differentiated depending on colour intensity. The neutral monosaccharide compositions of the non-cellulosic polysaccharides of these wood types were determined on small, well defined discs, and showed the proportion of galactose was higher for CWs and increased with severity. Conclusion: The presence of an S3 wall layer is a marker for very MCW and the presence of helical cavities in the S2 wall layer for SCW. The occurrence and proportions of (1→4)-β-D-galactans and (1→3)-β-D-glucans can be used as markers for CW and its severity. The proportions of galactose were consistent with the labelling results for (1→4)-β-D-galactans. [ABSTRACT FROM AUTHOR]

Borrelia burgdorferi is the causative agent of tick-borne Lyme disease. As a response to environmental stress B. burgdorferi can change its morphology to a round body form. The role of B. burgdorferi pleomorphic forms in Lyme disease pathogenesis has long been debated and unclear. Here, we demonstrated that round bodies were processed differently in differentiated macrophages, consequently inducing distinct immune responses compared to spirochetes in vitro . Colocalization analysis indicated that the F-actin participates in internalization of both forms. However, round bodies end up less in macrophage lysosomes than spirochetes suggesting that there are differences in processing of these forms in phagocytic cells. Furthermore, round bodies stimulated distinct cytokine and chemokine production in these cells. We confirmed that spirochetes and round bodies present different protein profiles and antigenicity. In a Western blot analysis Lyme disease patients had more intense responses to round bodies when compared to spirochetes. These results suggest that round bodies have a role in Lyme disease pathogenesis. [ABSTRACT FROM AUTHOR]

In accordance with recent terminology, it is proposed that malignant mesenchymoma should be renamed 'composite sarcoma' and defined as 'a sarcoma composed of two or more cellular types each of which is sufficiently differentiated to permit clear recognition of its histogenetic type microscopically, immunohistochemically or ultrastructurally; excluding fibrosarcomatous and high-grade pleomorphic undifferentiated sarcomatous component, dedifferentiated sarcoma and the combination of osteosarcoma and chondrosarcoma which is regarded as a single histogenetic type'. Four cases of primary osseous composite sarcoma ( POCS) were identified among 928 primary bone sarcomas. Their age ranged from 10 to 87 years, peak incidence in the second decade with equal sex distribution. Most presented with pain, commonest in the knee, affecting the metaphysis, appearing radiologically as expansile infiltrative osteolytic lesions with cortical erosion, periosteal reaction, variable extent of osteoblastic areas and soft tissue extension. All contained variable amounts of conventional high-grade osteosarcoma with or without chondrosarcoma component; the other constituents were liposarcoma, rhabdomyosarcoma and leiomyosarcoma. In all cases, Ki67 proliferative index was over 35%, there was no CDK4 and MDM2 amplification. The absence of low-grade component supported the de novo origin of POCS rather than derivation from divergent dedifferentiation. The two older patients with hitherto undescribed osteoleiomyosarcoma died 2 and 10 months after operation, whereas the two younger with osteorhabdomyosarcoma and osteoliposarcoma enjoyed disease-free survival at 16 and 6 years after chemotherapy despite the latter showing lung metastasis at presentation. Identification of the different lines of differentiation together with their approximate amounts and histological grades is therefore mandatory for POCS as multi-agent chemotherapy catered for each sarcoma component might offer hope for long-term disease-free survival. [ABSTRACT FROM AUTHOR]

Background Understanding the incidence and characteristics of multiple primary malignancies (MPM) has implications for guiding appropriate treatment and surveillance of extremity soft tissue sarcoma (STS). Objectives We sought to examine the incidence of MPM in STS (MPM-STS), and compare their clinicopathologic characteristics and survival to those with STS only. Methods 585 patients who underwent surgery for extremity STS were reviewed. Logistic regression analyses to identify factors contributing to the development of MPMs and a 1:2 matched case–control analysis to compare survival outcome were performed. Results Of the 585 patients analyzed, 34 (6%) with MPM were identified. On univariate logistic regression analysis, older age (>49 years) at STS diagnosis (p = 0.008) and histologic types of undifferentiated pleomorphic sarcoma or myxofibrosarcoma (p = 0.033) were significant. In multivariate analysis, only older age at STS diagnosis remained significant (OR = 2.5, p = 0.029). Cancer-specific survival of the MPM-STS group was significantly lower than that of the STS-only group (p = 0.031). However, there was no significant difference in STS-specific survival between the two groups (p = 0.208). Conclusion Our study suggests that MPM is not uncommon in extremity STS and older age at STS diagnosis is associated with risk of MPM. Prognosis of STS in the MPM-STS group seems similar to that of the STS-only group. [ABSTRACT FROM AUTHOR]

As obligate aerobic soil organisms, the ability of Azotobacter species to fix nitrogen is unusual given that the nitrogenase complex requires a reduced cellular environment. Molecular hydrogen is an unavoidable byproduct of the reduction of dinitrogen; at least one molecule of H is produced for each molecule of N fixed. This could be considered a fault in nitrogenase efficiency, essentially a waste of energy and reducing equivalents. Wild-type Azotobacter captures this hydrogen and oxidizes it with its membrane-bound uptake hydrogenase complex. Strains lacking an active hydrogenase complex have been investigated for their hydrogen production capacities. What is the role of H in the energy metabolism of nitrogen-fixing Azotobacter? Is hydrogen production involved in Azotobacter species' protection from or tolerance to oxygen, or vice versa? What yields of hydrogen can be expected from hydrogen-evolving strains? Can the yield of hydrogen be controlled or increased by changing genetic, environmental, or physiological conditions? We will address these questions in the following mini-review. [ABSTRACT FROM AUTHOR]

We report the first case of early-onset systemic neonatal infection associated with Moraxella osloensis bacteriemia in a full term baby. The genus Moraxella is constituted by a group of pleomorphic bacteria obligate aerobes, Gram-negative, oxidase positive and indole negative infrequently isolated from clinical specimens. The organism is rarely reported in the literature as the causative agent of infection in humans, mostly in immunocompromised patients. Only 12 cases of M. osloensisrelated infections during childhood have been reported in the literature so far. This unique report of M. osloensis infection, during the neonatal period, concerns the isolation of the bacteria in purulent secretions from the eyes of a 3-week-old baby with opthalmia. In our patient, the precocity of the onset of symptoms allows us to hypothesize a vertical transmission of the bacteria. [ABSTRACT FROM AUTHOR]

Salivary gland tumors are rare, comprising less than 3% of all neoplasia of head and neck region. Pleomorphic adenoma is the most common type of all salivary gland tumors. It exhibits wide cyto-morphologic and architectural diversity and that is how it is considered to mixed tumor. Due to few symptoms and extension into a hidden site, the tumor can grow for a long time before being diagnosed, and the potential risk for malignant transformation increases over the years with the incidence of 1-7%. Hereby, we report a case of pleomorphic adenoma in a 46 year-old male who complained of a large growth on the left side of the face, which enlarged gradually over a period of over 10 years. Advanced imaging modality was used to determine the exact location and extent of the tumor so as to carry out its complete resection for a favourable outcome. [ABSTRACT FROM AUTHOR]

Synchronous benign and malignant tumours in the ipsilateral parotid gland are rare. We present a case of pleomorphic adenoma and oncocytic carcinoma in the same parotid gland. Clinicians should be aware of the possibility of such synchronous multiple tumours, and that careful dissection and palpation during operation are important to diagnose them. [ABSTRACT FROM AUTHOR]

Background: Pleomorphic invasive lobular cancer (pleomorphic ILC) is a rare variant of ILC that is characterized by a classic ILC-like growth pattern combined with an infiltrative ductal cancer (IDC)-like high nuclear atypicality. There is an ongoing discussion whether pleomorphic ILC is a dedifferentiated form of ILC or in origin an IDC with a secondary loss of cohesion. Since gene promoter hypermethylation is an early event in breast carcinogenesis and thus may provide information on tumor progression, we set out to compare the methylation patterns of pleomorphic ILC, classic ILC and IDC. In addition, we aimed at analyzing the methylation status of pleomorphic ILC. Methods: We performed promoter methylation profiling of 24 established and putative tumor suppressor genes by methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) analysis in 20 classical ILC, 16 pleomorphic ILC and 20 IDC cases. Results: We found that pleomorphic ILC showed relatively low TP73 and MLH1 methylation levels and relatively high RASSF1A methylation levels compared to classic ILC. Compared to IDC, pleomorphic ILC showed relatively low MLH1 and BRCA1 methylation levels. Hierarchical cluster analysis revealed a similar methylation pattern for pleomorphic ILC and IDC, while the methylation pattern of classic ILC was different. Conclusion: This is the first report to identify TP73, RASSF1A, MLH1 and BRCA1 as possible biomarkers to distinguish pleomorphic ILC from classic ILC and IDC. [ABSTRACT FROM AUTHOR]