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1.
PLoS Genet ; 17(11): e1009908, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34793451

RESUMEN

EHMT2 is the main euchromatic H3K9 methyltransferase. Embryos with zygotic, or maternal mutation in the Ehmt2 gene exhibit variable developmental delay. To understand how EHMT2 prevents variable developmental delay we performed RNA sequencing of mutant and somite stage-matched normal embryos at 8.5-9.5 days of gestation. Using four-way comparisons between delayed and normal embryos we clarified what it takes to be normal and what it takes to develop. We identified differentially expressed genes, for example Hox genes that simply reflected the difference in developmental progression of wild type and the delayed mutant uterus-mate embryos. By comparing wild type and zygotic mutant embryos along the same developmental window we detected a role of EHMT2 in suppressing variation in the transcriptional switches. We identified transcription changes where precise switching during development occurred only in the normal but not in the mutant embryo. At the 6-somite stage, gastrulation-specific genes were not precisely switched off in the Ehmt2-/- zygotic mutant embryos, while genes involved in organ growth, connective tissue development, striated muscle development, muscle differentiation, and cartilage development were not precisely switched on. The Ehmt2mat-/+ maternal mutant embryos displayed high transcriptional variation consistent with their variable survival. Variable derepression of transcripts occurred dominantly in the maternally inherited allele. Transcription was normal in the parental haploinsufficient wild type embryos despite their delay, consistent with their good prospects. Global profiling of transposable elements revealed EHMT2 targeted DNA methylation and suppression at LTR repeats, mostly ERVKs. In Ehmt2-/- embryos, transcription over very long distances initiated from such misregulated 'driver' ERVK repeats, encompassing a multitude of misexpressed 'passenger' repeats. In summary, EHMT2 reduced transcriptional variation of developmental switch genes and developmentally switching repeat elements at the six-somite stage embryos. These findings establish EHMT2 as a suppressor of transcriptional and developmental variation at the transition between gastrulation and organ specification.


Asunto(s)
Embrión de Mamíferos/metabolismo , Regulación del Desarrollo de la Expresión Génica , N-Metiltransferasa de Histona-Lisina/metabolismo , Transcripción Genética , Animales , Islas de CpG , Metilación de ADN , Femenino , Haploinsuficiencia , N-Metiltransferasa de Histona-Lisina/genética , Ratones , Transcriptoma
2.
Mol Psychiatry ; 27(11): 4754-4769, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35948662

RESUMEN

Vascular cognitive impairment and dementia (VCID) is the second most common form of dementia after Alzheimer's disease (AD). Currently, the mechanistic insights into the evolution and progression of VCID remain elusive. White matter change represents an invariant feature. Compelling clinical neuroimaging and pathological evidence suggest a link between white matter changes and neurodegeneration. Our prior study detected hypoperfused lesions in mice with partial deficiency of endothelial nitric oxide (eNOS) at very young age, precisely matching to those hypoperfused areas identified in preclinical AD patients. White matter tracts are particularly susceptible to the vascular damage induced by chronic hypoperfusion. Using immunohistochemistry, we detected severe demyelination in the middle-aged eNOS-deficient mice. The demyelinated areas were confined to cortical and subcortical areas including the corpus callosum and hippocampus. The intensity of demyelination correlated with behavioral deficits of gait and associative recognition memory performances. By Evans blue angiography, we detected blood-brain barrier (BBB) leakage as another early pathological change affecting frontal and parietal cortex in eNOS-deficient mice. Sodium nitrate fortified drinking water provided to young and middle-aged eNOS-deficient mice completely prevented non-perfusion, BBB leakage, and white matter pathology, indicating that impaired endothelium-derived NO signaling may have caused these pathological events. Furthermore, genome-wide transcriptomic analysis revealed altered gene clusters most related to mitochondrial respiratory pathways selectively in the white matter of young eNOS-deficient mice. Using eNOS-deficient mice, we identified BBB breakdown and hypoperfusion as the two earliest pathological events, resulting from insufficient vascular NO signaling. We speculate that the compromised BBB and mild chronic hypoperfusion trigger vascular damage, along with oxidative stress and astrogliosis, accounting for the white matter pathological changes in the eNOS-deficient mouse model. We conclude that eNOS-deficient mice represent an ideal spontaneous evolving model for studying the earliest events leading to white matter changes, which will be instrumental to future therapeutic testing of drug candidates and for targeting novel/specific vascular mechanisms contributing to VCID and AD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Demencia Vascular , Sustancia Blanca , Animales , Ratones , Sustancia Blanca/patología , Óxido Nítrico/metabolismo , Circulación Cerebrovascular , Demencia Vascular/patología , Demencia Vascular/psicología , Modelos Animales de Enfermedad , Disfunción Cognitiva/metabolismo , Enfermedad de Alzheimer/metabolismo
3.
Nanomedicine ; 40: 102487, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34740869

RESUMEN

Induced pluripotent stem cells (iPSCs) are a promising cell source for regenerative medicine. However, their feeder-free maintenance in undifferentiated states remains challenging. In recent past extensive studies have been directed using pristine or functionalized carbon nanotube in tissue engineering. Here we proposed thin films of functionalized carbon nanotubes (OH-single-walled CNTs [SWCNTs] and OH-multiwalled CNTs [MWCNTs]), as alternatives for the feeder-free in vitro culture of canine iPSCs (ciPSCs), considered as the cellular model. The ciPSC colonies could maintain their dome-shaped compactness and other characteristics when propagated on CNT films. Concomitantly, high cell viability and upregulation of pluripotency-associated genes and cell adhesion molecules were observed, further supported by molecular docking. Moreover, CNTs did not have profound toxic effects compared to feeder cultures as evident by cytocompatibility studies. Further, cardiac and neuronal differentiation of ciPSCs was induced on these films to determine their influence on the differentiation process. The cells retained differentiation potential and the nanotopographical features of the substrates provided positive cues to enhance differentiation to both lineages as evident by immunocytochemical staining and marker gene expression. Overall, OH-SWCNT provided better cues, maintained pluripotency, and induced the differentiation of ciPSCs. These results indicate that OH-functionalized CNT films could be used as alternatives for the feeder-free maintenance of ciPSCs towards prospective utilization in regenerative medicine.


Asunto(s)
Células Madre Pluripotentes Inducidas , Nanotubos de Carbono , Animales , Diferenciación Celular/fisiología , Perros , Simulación del Acoplamiento Molecular , Nanotubos de Carbono/química , Estudios Prospectivos
4.
Proc Natl Acad Sci U S A ; 115(29): 7521-7526, 2018 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-29959208

RESUMEN

Biologists and social scientists have long tried to understand why some societies have more fluid and open interpersonal relationships and how those differences influence culture. This study measures relational mobility, a socioecological variable quantifying voluntary (high relational mobility) vs. fixed (low relational mobility) interpersonal relationships. We measure relational mobility in 39 societies and test whether it predicts social behavior. People in societies with higher relational mobility report more proactive interpersonal behaviors (e.g., self-disclosure and social support) and psychological tendencies that help them build and retain relationships (e.g., general trust, intimacy, self-esteem). Finally, we explore ecological factors that could explain relational mobility differences across societies. Relational mobility was lower in societies that practiced settled, interdependent subsistence styles, such as rice farming, and in societies that had stronger ecological and historical threats.


Asunto(s)
Agricultura , Conducta Social , Movilidad Social , Femenino , Humanos , Masculino
5.
Cancer ; 126(17): 4051-4058, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32413235

RESUMEN

BACKGROUND: Anthracycline-related cardiomyopathy is a leading cause of late morbidity in childhood cancer survivors. Glutathione S-transferases (GSTs) are a class of phase II detoxification enzymes that facilitate the elimination of anthracyclines. As free-radical scavengers, GSTs could play a role in oxidative damage-induced cardiomyopathy. Associations between the GSTµ1 (GSTM1) null genotype and iron-overload-related cardiomyopathy have been reported in patients with thalassemia. METHODS: The authors sought to identify an association between the GSTM1 null genotype and anthracycline-related cardiomyopathy in childhood cancer survivors and to corroborate the association by examining GSTM1 gene expression in peripheral blood and human-induced pluripotent stem cell cardiomyocytes (hiPSC-CMs) from survivors with and without cardiomyopathy. GSTM1 gene deletion was examined by polymerase chain reaction in 75 survivors who had clinically validated cardiomyopathy (cases) and in 92 matched survivors without cardiomyopathy (controls). Conditional logistic regression analysis adjusting for sex, age at cancer diagnosis, chest radiation, and anthracycline dose was used to assess the association between genotype and cardiomyopathy. Proprietary bead array technology and quantitative real-time polymerase chain reaction were used to measure GSTM1 expression levels in samples from 20 cases and 20 matched controls. hiPSC-CMs from childhood cancer survivors (3 with cardiomyopathy, 3 without cardiomyopathy) also were examined for GSTM1 gene expression levels. RESULTS: A significant association was observed between the risk of cardiomyopathy and the GSTM1 null genotype (odds ratio, 2.7; 95% CI, 1.3-5.9; P = .007). There was significant downregulation of GSTM1 expression in cases compared with controls (average relative expression, 0.67 ± 0.57 vs 1.33 ± 1.33, respectively; P = .049). hiPSC-CMs from patients who had cardiomyopathy revealed reduced GSTM1 expression (P = .007). CONCLUSIONS: The current findings could facilitate the identification of childhood cancer survivors who are at risk for anthracycline-related cardiomyopathy.


Asunto(s)
Antraciclinas/administración & dosificación , Cardiomiopatías/genética , Glutatión Transferasa/genética , Neoplasias/tratamiento farmacológico , Adolescente , Antraciclinas/efectos adversos , Supervivientes de Cáncer , Cardiomiopatías/sangre , Cardiomiopatías/etiología , Cardiomiopatías/patología , Niño , Preescolar , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Masculino , Neoplasias/complicaciones , Neoplasias/genética , Neoplasias/patología , Estrés Oxidativo/efectos de los fármacos
6.
Int J Mol Sci ; 20(7)2019 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-30935059

RESUMEN

Transcriptional regulation includes both activation and repression of downstream genes. In plants, a well-established class of repressors are proteins with an ERF-associated amphiphilic repression/EAR domain. They contain either DLNxxP or LxLxL as the identifying hexapeptide motif. In rice (Oryza sativa), we have identified a total of 266 DLN repressor proteins, with the former motif and its modifications thereof comprising 227 transcription factors and 39 transcriptional regulators. Apart from DLNxxP motif conservation, DLNxP and DLNxxxP motifs with variable numbers/positions of proline and those without any proline conservation have been identified. Most of the DLN repressome proteins have a single DLN motif, with higher relative percentage in the C-terminal region. We have designed a simple yeast-based experiment wherein a DLN motif can successfully cause strong repression of downstream reporter genes, when fused to a transcriptional activator of rice or yeast. The DLN hexapeptide motif is essential for repression, and at least two "DLN" residues cause maximal repression. Comparatively, rice has more DLN repressor encoding genes than Arabidopsis, and DLNSPP motif from rice is 40% stronger than the known Arabidopsis SRDX motif. The study reports a straightforward assay to analyze repressor activity, along with the identification of a strong DLN repressor from rice.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Represoras/metabolismo , Secuencias de Aminoácidos , Oryza/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas Represoras/química , Proteínas Represoras/genética
7.
Phys Rev Lett ; 121(19): 192501, 2018 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-30468600

RESUMEN

The lifetimes of the first excited 2^{+}, 4^{+}, and 6^{+} states in ^{98}Zr were measured with the recoil-distance Doppler shift method in an experiment performed at GANIL. Excited states in ^{98}Zr were populated using the fission reaction between a 6.2 MeV/u ^{238}U beam and a ^{9}Be target. The γ rays were detected with the EXOGAM array in correlation with the fission fragments identified by mass and atomic number in the VAMOS++ spectrometer. Our result shows a very small B(E2;2_{1}^{+}→0_{1}^{+}) value in ^{98}Zr, thereby confirming the very sudden onset of collectivity at N=60. The experimental results are compared to large-scale Monte Carlo shell model and beyond-mean-field calculations. The present results indicate the coexistence of two additional deformed shapes in this nucleus along with the spherical ground state.

8.
J Relig Health ; 57(6): 2066-2078, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28577087

RESUMEN

The study examined the impact of frequency of ritual participation on sense of community and social well-being of a minority community in India, the Sikhs. We looked at a unique ritualistic practice of the Sikhs, seva. Rituals are known to contribute toward social solidarity and cohesion as well as physical and mental well-being. In particular for a minority community, rituals help group members establish and maintain strong community networks and a unique group identity. A total of 156 members of the Sikh community (85 males; 71 females) participated in the study. Frequency of ritual participation was positively related with social well-being and sense of community. Furthermore, sense of community was found to mediate the effect of frequency of ritual participation on social well-being. Results are discussed in the light of the importance of studying rituals in minority groups, the frequency of participation in a ritual activity and the importance of addressing social well-being in ritual research.


Asunto(s)
Conducta Ceremonial , Religión , Participación Social , Percepción Social , Cultura , Femenino , Humanos , India , Masculino
9.
J Basic Microbiol ; 57(12): 1018-1036, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28940222

RESUMEN

Permafrost soils are unique habitats in polar environment and are of great ecological relevance. The present study focuses on the characterization of bacterial communities from permafrost profiles of Svalbard, Arctic. Counts of culturable bacteria range from 1.50 × 103 to 2.22 × 105 CFU g-1 , total bacterial numbers range from 1.14 × 105 to 5.52 × 105 cells g-1 soil. Bacterial isolates are identified through 16S rRNA gene sequencing. Arthrobacter and Pseudomonas are the most dominant genera, and A. sulfonivorans, A. bergeri, P. mandelii, and P. jessenii as the dominant species. Other species belong to genera Acinetobacter, Bacillus, Enterobacter, Nesterenkonia, Psychrobacter, Rhizobium, Rhodococcus, Sphingobacterium, Sphingopyxis, Stenotrophomonas, and Virgibacillus. To the best of our knowledge, genera Acinetobacter, Enterobacter, Nesterenkonia, Psychrobacter, Rhizobium, Sphingobacterium, Sphingopyxis, Stenotrophomonas, and Virgibacillus are the first northernmost records from Arctic permafrost. The present study fills the knowledge gap of culturable bacterial communities and their chronological characterization from permafrost soils of Ny-Ålesund (79°N), Arctic.


Asunto(s)
Bacterias/clasificación , Bacterias/genética , Biota , Hielos Perennes/microbiología , Regiones Árticas , Carga Bacteriana , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Svalbard
10.
Nucleic Acids Res ; 42(3): 1772-83, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24217910

RESUMEN

Mouse embryo fibroblasts (MEFs) are convenient sources for biochemical studies when cell number in mouse embryos is limiting. To derive the imprinting signature of MEFs and potentially detect novel imprinted genes we performed strand- and allele-specific RNA deep sequencing. We used sequenom allelotyping in embryo and adult organs to verify parental allele-specific expression. Thirty-two known ubiquitously imprinted genes displayed correct parental allele-specific transcripts in MEFs. Our analysis did not reveal any novel imprinted genes, but detected extended parental allele-specific transcripts in several known imprinted domains: maternal allele-specific transcripts downstream of Grb10 and downstream of Meg3, Rtl1as and Rian in the Dlk1-Dio3 cluster, an imprinted domain implicated in development and pluripotency. We detected paternal allele-specific transcripts downstream of Nespas, Peg3, Peg12 and Snurf/Snrpn. These imprinted transcript extensions were not unique to MEFs, but were also present in other somatic cells. The 5' end points of the imprinted transcript extensions did not carry opposing chromatin marks or parental allele-specific DNA methylation, suggesting that their parental allele-specific transcription is under the control of the extended imprinted genes. Based on the imprinting signature of MEFs, these cells provide valid models for understanding the biochemical aspects of genomic imprinting.


Asunto(s)
Impresión Genómica , Alelos , Animales , Células Cultivadas , Cruzamientos Genéticos , Embrión de Mamíferos/citología , Fibroblastos/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Ratones , Análisis de Secuencia de ARN , Transcripción Genética
11.
J Basic Microbiol ; 56(3): 275-85, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26567474

RESUMEN

Glacier ice and firn cores have ecological and biotechnological importance. The present study is aimed at characterizing bacteria in crustal ice cores from Svalbard, the Arctic. Counts of viable isolates ranged from 10 to 7000 CFU/ml (mean 803 CFU/ml) while the total bacterial numbers ranged from 7.20 × 10(4) to 2.59 × 10(7) cells ml(-1) (mean 3.12 × 10(6) cells ml(-1) ). Based on 16S rDNA sequence data, the identified species belonged to seven species, namely Bacillus barbaricus, Pseudomonas orientalis, Pseudomonas oryzihabitans, Pseudomonas fluorescens, Pseudomonas syncyanea, Sphingomonas dokdonensis, and Sphingomonas phyllosphaerae, with a sequence similarity ranging between 93.5 and 99.9% with taxa present in the database. The isolates exhibited unique phenotypic properties, and three isolates (MLB-2, MLB-5, and MLB-9) are novel species, yet to be described. To the best of our knowledge, this is the first report on characterization of cultured bacterial communities from Svalbard ice cores. We conclude that high lipase, protease, cellulase, amylase, and urease activities expressed by most of the isolates provide a clue to the potential industrial applications of these organisms. These microbes, producing cold-adapted enzymes may provide an opportunity for biotechnological research.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Enzimas/metabolismo , Cubierta de Hielo/microbiología , Adaptación Fisiológica , Proteínas Anticongelantes/metabolismo , Regiones Árticas , Bacterias/enzimología , Bacterias/genética , Proteínas Bacterianas/genética , Biodiversidad , Frío , ADN Bacteriano/genética , ADN Ribosómico/genética , Activación Enzimática , Enzimas/análisis , Ácidos Grasos/metabolismo , Microbiología Industrial , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
12.
Arch Gynecol Obstet ; 291(3): 701-3, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25149171

RESUMEN

Fetal destructive operation is a vanishing art today. In an era of increasing cesarean deliveries it has become a historic event. Incidence of destructive operation has varied from various Indian hospitals 0.09-0.28%. Evisceration is one of the rarest of all destructive operations, performed in cases of cephalopelvic disproportion with large fetal abdominal or thoracic tumors and fetal malformations, which are incompatible with life. Less than 50 cases of fetal evisceration have been reported in the literature so far. We are presenting a case of gross fetal abdominal malformation in a multigravida woman, which necessitated internal podalic version followed by evisceration and breech extraction.


Asunto(s)
Parto Obstétrico/métodos , Feto/anomalías , Complicaciones del Trabajo de Parto/cirugía , Cesárea , Femenino , Muerte Fetal , Feto/cirugía , Humanos , Embarazo , Adulto Joven
13.
Extremophiles ; 18(2): 229-42, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24346230

RESUMEN

Cryoconite holes have biogeochemical, ecological and biotechnological importance. This communication presents results on culturable psychrophilic bacterial diversity from cryoconite holes at Midre Lovénbreen (ML), Austre Brøggerbreen (AB), and Vestre Brøggerbreen (VB) glaciers. The culturable bacterial count ranged from 2.7 × 10(3) to 8.8 × 10(4) CFUs/g while the total bacterial numbers ranged from 5.07 × 10(5) to 1.50 × 10(6) cells at the three glaciers. A total of 35 morphologically distinct bacterial isolates were isolated. Based on 16S rRNA gene sequence data, the identified species belonged to eight genera namely Pseudomonas, Polaromonas, Micrococcus, Subtercola, Agreia, Leifsonia, Cryobacterium and Flavobacterium. The isolates varied in their growth temperature, NaCl tolerance, growth pH, enzyme activities, carbon utilization and antibiotic sensitivity tests. Fatty acid profiles indicate the predominance of branched fatty acids in the isolates. To the best of our knowledge, this is the first record of culturable bacterial communities and their characterization from glacier cryoconites from High Arctic. High amylase and protease activities expressed by Micrococcus sp. MLB-41 and amylase, protease and lipase activities expressed by Cryobacterium sp. MLB-32 provide a clue to the potential applications of these organisms. These cold-adapted enzymes may provide an opportunity for the prospect of biotechnology in Arctic.


Asunto(s)
Adaptación Fisiológica , Bacterias/aislamiento & purificación , Cubierta de Hielo/microbiología , Microbiota , Regiones Árticas , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Enzimas/genética , Enzimas/metabolismo , Fenotipo
14.
Nat Med ; 13(7): 812-9, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17589521

RESUMEN

Functional deficiency of the FEN1 gene has been suggested to cause genomic instability and cancer predisposition. We have identified a group of FEN1 mutations in human cancer specimens. Most of these mutations abrogated two of three nuclease activities of flap endonuclease 1 (FEN1). To demonstrate the etiological significance of these somatic mutations, we inbred a mouse line harboring the E160D mutation representing mutations identified in human cancers. Selective elimination of nuclease activities led to frequent spontaneous mutations and accumulation of incompletely digested DNA fragments in apoptotic cells. The mutant mice were predisposed to autoimmunity, chronic inflammation and cancers. The mutator phenotype results in the initiation of cancer, whereas chronic inflammation promotes the cancer progression. The current work exemplifies the approach of studying the mechanisms of individual polymorphisms and somatic mutations in cancer development, and may serve as a reference in developing new therapeutic regimens through the suppression of inflammatory responses.


Asunto(s)
Enfermedades Autoinmunes/genética , Endonucleasas de ADN Solapado/genética , Inflamación/genética , Neoplasias/genética , Animales , Apoptosis , Enfermedad Crónica , Fragmentación del ADN , Reparación del ADN , Humanos , Ratones , Mutación , Neoplasias/metabolismo
15.
Appl Microbiol Biotechnol ; 98(13): 5789-805, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24805845

RESUMEN

Thraustochytrids, a group of osmoheterotrophic marine protists, have recently gained increased attention owing to their spectacular biotechnological potentials. They possess enormous capability of producing omega-3 (ω-3) polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and several other bioactive metabolites, known to have nutritional implications in human health. They have emerged lately as an efficient economic alternative compared with other fish and algal oil sources by virtue of their simpler PUFA profiles and cost-effective culture conditions. This review is an attempt to summarize the ecological significance of thraustochytrids with an emphasis on their cultured and uncultured diversity from various marine habitats accounted during the last few decades. Moreover, improved technologies such as media optimization in conjugation with metabolic engineering, adopted for biotechnological advancement of ω-3 products of thraustochytrids are highlighted with particular concern on the respective fatty acid biosynthetic pathways. One of the future prospects focuses on utilization of thraustochytrids for biodiesel production owing to their tremendous potentiality of yielding low carbon monounsaturated fatty acids (LC-MUFAs). However, there is utmost need of in-depth diversity assessments from various oceanic ecosystems in order to gain insight on potential thraustochytrids for ameliorated employment toward biotechnological applications.


Asunto(s)
Biotecnología/métodos , Ecosistema , Metabolismo de los Lípidos , Agua de Mar/parasitología , Estramenopilos/metabolismo , Organismos Acuáticos
16.
Appl Microbiol Biotechnol ; 98(7): 3241-55, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24270895

RESUMEN

Thraustochytrids are ubiquitous marine osmo-heterotrophic fungi-like microorganisms with only about 40 identified species till now. In this study, a total of 60 thraustochytrid strains were isolated from marine coastal habitats. Analysis of 18S rRNA gene sequences revealed that they belonged to three genera, i.e., Schizochytrium, Aurantiochytrium, and Thraustochytrium. All of the isolates were found to show considerable cellulolytic and lipolytic activities. Strains of Aurantiochytrium sp. and Thraustochytrium sp. were found to produce the highest levels of extracellular polysaccharides (EPS), which reached 345 µg ml(-1) in the growth media. Fourier transform infrared (FTIR) spectra of the EPS samples derived from two thraustochytrids (PKU#Sed1 and #SW1) displayed peaks for carbohydrates, proteins, lipids, uronic acids, and nucleic acids. Fatty acid profiles of four thraustochytrids comprised of palmitic acid (C16:0) and docosahexaenoic acid (DHA) as their major constituents. Schizochytrium sp. demonstrated the highest DHA production at 44 % of total fatty acids (TFA) with biomass and DHA yield of 7.1 and 1.6 g l(-1), respectively, on the fourth day of growth. All the four isolates exhibited considerable production of palmitic acid (16:0) in their fatty acid profiles ranging from 35 to 50 % TFA. This is the first report on extracellular enzymes, EPS, and DHA production from thraustochytrids isolated from the coastal habitats of China.


Asunto(s)
Biodiversidad , Agua de Mar/microbiología , Estramenopilos/crecimiento & desarrollo , Estramenopilos/metabolismo , China , Lípidos/análisis , Datos de Secuencia Molecular , Ácidos Nucleicos/análisis , Polisacáridos/análisis , Proteínas/análisis , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN , Estramenopilos/química , Estramenopilos/genética , Ácidos Urónicos/análisis
17.
Cryobiology ; 68(1): 122-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24463093

RESUMEN

A psychrophilic yeast species was isolated from glacier cryoconite holes of Svalbard. Nucleotide sequences of the strains were studied using D1/D2 domain, ITS region and partial sequences of mitochondrial cytochrome b gene. The strains belonged to a clade of psychrophilic yeasts, but showed marked differences from related species in the D1/D2 domain and biochemical characters. Effects of temperature, salt and media on growth of the cultures were also studied. Screening of the cultures for amylase, cellulase, protease, lipase, urease and catalase activities was carried out. The strains expressed high amylase and lipase activities. Freeze tolerance ability of the isolates indicated the formation of unique hexagonal ice crystal structures due to presence of 'antifreeze proteins' (AFPs). FAME analysis of cultures showed a unique trend of increase in unsaturated fatty acids with decrease in temperature. The major fatty acids recorded were oleic acid, linoleic acid, linolenic acid, palmitic acid, stearic acid, myristic acid and pentadecanoic acid. Based on sequence data and, physiological and morphological properties of the strains, we propose a novel species, Rhodotorula svalbardensis and designate strains MLB-I (CCP-II) and CRY-YB-1 (CBS 12863, JCM 19699, JCM 19700, MTCC 10952) as its type strains (Etymology: sval.bar.den'sis. N.L. fem. adj. svalbardensis pertaining to Svalbard).


Asunto(s)
Citocromos b/clasificación , ADN Intergénico/clasificación , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Filogenia , Rhodotorula/clasificación , Amilasas/genética , Amilasas/metabolismo , Proteínas Anticongelantes/genética , Proteínas Anticongelantes/metabolismo , Regiones Árticas , Frío , Citocromos b/genética , ADN Intergénico/genética , Ácidos Grasos Insaturados/metabolismo , Proteínas Fúngicas/metabolismo , Cubierta de Hielo/microbiología , Lipasa/genética , Lipasa/metabolismo , Estructura Terciaria de Proteína , Rhodotorula/enzimología , Rhodotorula/genética
18.
Arch Gynecol Obstet ; 290(4): 819-23, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24947325

RESUMEN

We are reporting two cases of uterine necrosis and lumbosacral-plexopathy in patients, who underwent pelvic vessel embolization (PVE) following postpartum hemorrhage. Embolization was performed with gelfoam slurry, polyvinyl alcohol (PVA) particles and coil in one patient and with gelfoam slurry only, in second patient. Both patients had lower limbs weakness and had persistent fever in the postembolization period. Nerve conduction study in both were suggestive of common peroneal and tibial neuropathy. An ultrasonography and computed tomography of abdomen and pelvis revealed bulky uterus with no identifiable endometrium and multiple air foci in subendometrial region suggestive of uterine necrosis, confirmed later by histology of expelled uterine mass. Lumbosacral ischemia resulting in paraparesis and uterine necrosis presenting as longstanding fever after embolization are extremely rare but overwhelming complications of embolization. Only 19 cases of uterine necrosis and <10 cases of lumbosacral plexopathy have been reported in the literature. The overall effectiveness of PVE is high in treatment of obstetric hemorrhage with low complication rate and highly selective PVE may further prevent these complication. To the best of our knowledge the co-existing uterine necrosis and lumbosacral plexopathy secondry to PVE has not been described prevoiusly in patients with postpartum hemorrhage. Both patients recovered with conservative management.


Asunto(s)
Plexo Lumbosacro , Enfermedades del Sistema Nervioso Periférico/etiología , Hemorragia Posparto/terapia , Embolización de la Arteria Uterina/efectos adversos , Útero/patología , Adulto , Femenino , Fiebre/etiología , Esponja de Gelatina Absorbible , Humanos , Necrosis , Paraparesia/etiología , Enfermedades del Sistema Nervioso Periférico/terapia , Modalidades de Fisioterapia , Hemorragia Posparto/etiología , Embarazo
19.
Front Microbiol ; 15: 1362678, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38751720

RESUMEN

Cryoconite is a granular structure present on the glaciers and ice sheets found in polar regions including the Himalayas. It is composed of organic and inorganic matter which absorb solar radiations and reduce ice surface albedo, therefore impacting the melting and retreat of glaciers. Though climate warming has a serious impact on Himalayan glaciers, the biodiversity of sub-glacier ecosystems is poorly understood. Moreover, cryoconite holes are unique habitats for psychrophile biodiversity hotspots in the NW Himalayas, but unfortunately, studies on the microbial diversity of such habitats remain elusive. Therefore, the current study was designed to explore the bacterial diversity of the Hamtah Glacier Himalaya using both culturable and non-culturable approaches. The culturable bacterial count ranged from 2.0 × 103 to 8.8 × 105 colony-forming units (CFUs)/g at the different locations of the glacier. A total of 88 bacterial isolates were isolated using the culturable approach. Based on the 16S ribosomal RNA gene (16S rRNA), the identified species belong to seven genera, namely, Cryobacterium, Duganella, Janthinobacterium, Pseudomonas, Peribacillus, Psychrobacter, and Sphingomonas. In the non-culturable approach, high-throughput sequencing of 16S rRNA genes (using MiSeq) showed unique bacterial community profiles and represented 440 genera belonging to 20 phyla, namely, Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, Chloroflexi, Acidobacteria, Planctomycetes, Cyanobacteria, Verrucomicrobia, Spirochaetes, Elusimicrobia, Armatimonadetes, Gemmatimonadetes, Deinococcus-Thermus, Nitrospirae, Chlamydiae, Chlorobi, Deferribacteres, Fusobacteria, Lentisphaerae, and others. High relative abundances of Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes were observed in the samples. Phototrophic (Cyanobacteria and Chloroflexi) and nitrifier (Nitrospirae) in bacterial populations indicated sustenance of the micro-ecosystem in the oligotrophic glacier environment. The isolates varied in their phenotypic characteristics, enzyme activities, and antibiotic sensitivity. Furthermore, the fatty acid profiles of bacterial isolates indicate the predominance of branched fatty acids. Iso-, anteiso-, unsaturated and saturated fatty acids together constituted a major proportion of the total fatty acid composition. High cold-adapted enzyme activities such as lipase and cellulase expressed by Cryobacterium arcticum (KY783365) and protease and cellulase activities by Pseudomonas sp. strains (KY783373, KY783377-79, KY783382) provide evidence of the possible applications of these organisms. Additionally, antibiotic tests indicated that most isolates were sensitive to antibiotics. In conclusion, the present study contributed for the first time to bacterial diversity and biopotentials of cryoconites of Hamtah Glacier, Himalayas. Furthermore, the cold-adapted enzymes and polyunsaturated fatty acids (PUFAs) may provide an opportunity for biotechnology in the Himalayas. Inductively coupled plasma mass spectrometry (ICPMS) analyses showed the presence of several elements in cryoconites, providing a clue for the accelerating melting and retreating of the Hamtah glacier.

20.
J Clin Oncol ; : JCO2302547, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38635938

RESUMEN

PURPOSE: Therapy-related myeloid neoplasm (t-MN) is a life-threatening complication of autologous peripheral blood stem cell transplantation (aPBSCT) for Hodgkin lymphoma (HL). Although previous studies have reported an association between clonal hematopoiesis (CH) in the infused PBSC product and subsequent post-aPBSCT risk of t-MN in patients with non-HL, information about patients with HL treated with aPBSCT is not available. METHODS: We constructed a retrospective cohort of 321 patients with HL transplanted at a median age of 34 years (range, 18-71). Targeted DNA sequencing of PBSC products performed for CH-associated or myeloid malignancy-associated genes identified pathogenic mutations in these patients. RESULTS: CH was identified in the PBSC product of 46 patients (14.3%) with most prominent representation of DNMT3A (n = 25), PPM1D (n = 7), TET2 (n = 7), and TP53 (n = 5) mutations. Presence of CH in the PBSC product was an independent predictor of t-MN (adjusted hazard ratio [aHR], 4.50 [95% CI, 1.54 to 13.19]). Notably all patients with TP53 mutations in the PBSC product developed t-MN, whereas none of the patients with DNMT3A mutations alone (without co-occurring TP53 or PPM1D mutations) did. Presence of TP53 and/or PPM1D mutations was associated with a 7.29-fold higher hazard of t-MN when compared with individuals carrying no CH mutations (95% CI, 1.72 to 30.94). The presence of TP53 and/or PPM1D mutations was also associated with a 4.17-fold higher hazard of nonrelapse mortality (95% CI, 1.25 to 13.87). There was no association between CH and relapse-related mortality. CONCLUSION: The presence of TP53 and/or PPM1D mutations in the PBSC product increases the risk of post-aPBSCT t-MN and nonrelapse mortality among patients with HL and may support alternative therapeutic strategies.

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