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1.
Adv Clin Exp Med ; 31(9): 999-1009, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35587221

RESUMO

BACKGROUND: Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS). Most exercise studies concentrate on the impact of exercise on cardiovascular system; this study aims to present the effects of exercise of varying intensity on the nervous system. Most recently in MS, positive outcomes were obtained with resistance and high-intensity exercises. This study also analyzes the effects of a prior conditioning program before the induction of demyelination and subsequent neuroprotective effects of such program. OBJECTIVES: To study and determine the neuroprotective and remyelinating effects of different intensity of aquatic exercise and a preconditioning exercise program on demyelination induced by oral administration of cuprizone (Cup). MATERIAL AND METHODS: Six groups of animals, each containing 6 rats, were used in the study. The groups were as follows: group I - control group; group II - Cup group; group III - treated with methylprednisolone (MP); group IV - treated with low-intensity exercise (LIE), free swimming for 40 min and high-intensity exercise (HIE); group V - treated with a resistance of 9% body weight and free swimming for 40 min; group VI - treated with preconditioning exercise (free swimming for 40 min for 3 weeks) before Cup administration followed by the same exercise protocol as for group V. All data were analyzed using one-way analysis of variance (ANOVA) with Tukey's test, by means of SigmaPlot v. 14.5 software. RESULTS: Similarly to the MP group, group VI showed a positive outcome. A value of p < 0.001 was considered statistically significant. Also, group VI showed improved areas of remyelination in histopathology, an increased expression of myelin basic protein (MBP), reduced expression of glial fibrillary acidic protein (GFAP) in corpus callosum, and improved gene expression of brain-derived neurotrophic factor (BDNF) in the hippocampus region. CONCLUSIONS: General fitness achieved through a preconditioning program combined with HIE showed neuroprotective effects, as evidenced by increased areas of remyelination and improved neuronal plasticity, observed mostly in group VI (conditioning+HIE).


Assuntos
Doenças Desmielinizantes , Esclerose Múltipla , Fármacos Neuroprotetores , Remielinização , Animais , Fator Neurotrófico Derivado do Encéfalo , Cuprizona/efeitos adversos , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/prevenção & controle , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida/efeitos adversos , Proteína Glial Fibrilar Ácida/metabolismo , Masculino , Metilprednisolona , Camundongos , Camundongos Endogâmicos C57BL , Proteína Básica da Mielina/efeitos adversos , Proteína Básica da Mielina/metabolismo , Plasticidade Neuronal , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Wistar
2.
Cureus ; 14(3): e22879, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35399425

RESUMO

Background The patella is also known as the kneecap. It lies in front of the knee joint and protects the joint from damage. It is the largest sesamoid bone in the body and is embedded within the quadriceps tendon. The morphometry of the patella is crucial in forensic analysis, designing of implants, and subsequent reconstruction procedures in the knee as it is a sesamoid bone, without periosteum, whereby the natural healing process becomes difficult. The dimensions of the implant are very crucial for a successful knee replacement procedure. This study aims to provide a comprehensive morphometric analysis of the patella and further compare the same between right and left-sided patella specimens. Methodology In total, 50 dry patella specimens, with 26 left-sided specimens and 24 right-sided specimens, were obtained for the study from the Department of Anatomy, Saveetha Medical College, Chennai. The parameters analyzed in the study included height, width, the thickness of the patella, length and width of the articular facets on medial and lateral aspects, and central ridge length. Results The morphometric analysis showed the mean height, width, and thickness of patella specimens were 4.07 cm, 4.12 cm, and 2.03 cm, respectively. The dimensions of the articular facet on the lateral aspect were found to show statistical variation compared to the dimensions of the medial articular facet, where p-values of <0.05 were taken as statistically significant. Based on Koyunco's Classification, 92% of patella specimens were of Type B. Conclusions The morphometric analysis of the patella in this study can be helpful in designing implants for reconstruction and for treating orthopedics in patellar reconstruction and fixation procedures.

3.
Cureus ; 14(3): e22941, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35411283

RESUMO

The basic framework of the term "respect" is equality recognition. Students and teachers in academic institutions can have varying definitions of respect. Respect in the learning environment is critical for student success. This study aims to look into how students' perceptions of the human body in the anatomy lab and their respect for them can be used to promote ethical obligations, humanitarian principles, and their interrelationships. It is a descriptive, questionnaire-based study with 20 questions and a consent form that involves 250 students in the first year of MBBS. Using Microsoft Excel 2019, the data were collected, tabulated, and interpreted using descriptive statistics. The donor oath is a way to emphasize that the human body in front of them was once alive. The donor oath establishes the groundwork for future efforts to adapt existing frameworks for ethical decision-making and humanitarian values.

4.
Cureus ; 14(2): e22137, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35308728

RESUMO

Background The vertebral artery (VA) forms the caudal part of the circle of Willis and is responsible for one-third of the blood supply of the cerebellum, pons, middle ear, and the upper part of the spinal cord and its meninges. The highest potential risk of injury to VA during cervical pedicle screw implantation is at C3 and then at C6. Knowledge about the morphometry of VA provides a better understanding of clinical conditions such as vertebra basilar insufficiency (VBI). Similarly, the knowledge of variation in the VA is needed during cervical pedicle screw implantation, which possesses the highest potential risk to VA at the C3 level. The origin of the vertebral artery from the aortic arch reached the upper cervical vertebra than the vertebral artery of subclavian origin. The length of the VA is greater on the left side than the right-side artery. Understanding and reporting of the same are essential to creating awareness that can aid in endarterectomy, angioplasty, and radiological procedures. Variations are noted in morphometry between sides. Aim To determine the morphometry of the vertebral artery (VA) with emphasis on the fourth segment (V4) and its variations using computed tomography angiogram (CTA). Materials and methods This present retrospective study was conducted in the Departments of Anatomy and Radiology and Imaging Sciences, Saveetha Medical College and Hospital. Participants were patients who took a head and neck CT for various clinical reasons. About 50 CT images, 33 male and 17 females, were selected from the archives. The length, diameter, and entry level of VA were studied. The data were tabulated and statistically analyzed. Result The mean length of VA was 24.49 ± 3.02 (cm) on the left side and 24.28 ± 3.91 (cm) on the right side in female subjects and was found to be 22.78 ± 1.7 (cm) on the left side and 21.5 ± 2.7 (cm) on the right side in male subjects. The mean diameter of VA at the level of the foramen magnum was 0.32 ± 0.05 (cm) on the right side and 0.322 ± 0.07 (cm) on the left side in females, 0.3 ± 0.064 (cm) on the left side and 0.26 ± 0.086 (cm) on the right side in males. Conclusion The length of VA was found to be statistically more on the left side than on the right side. The variations in morphometry seen can aid in various surgical and radiological procedures.

5.
Cureus ; 14(2): e22263, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35350490

RESUMO

Background Sexual dimorphism in human bones has mostly been confined to the study of the bony pelvis. However, considerable changes also exist in the other parts of the skeletal system. This study focuses on the differences in the morphometry of male and female adult scaphoids. Aims and objectives We aim to study the morphometry of male and female adult human scaphoids and determine the differences between the same. Materials and methods A total of 100 scaphoids were freshly dissected from both hands of 25 male and 25 female cadavers in Saveetha Medical College, Chennai, India. The soft tissues were loosened using 5% potassium hydroxide (KOH) solution. Further, the soft tissues were removed by meticulous dissection. For the measurements, vernier calipers and threads for circumference measurement were used. Results The morphometric parameters included length, proximal width, width of the middle part (waist), distal width and circumference of the waist, and circumference of the tubercle in scaphoids. Statistical differences were found in most of the parameters. Conclusion A statistically significant difference exists between the morphometric measurements of male and female adult scaphoids, which may prove helpful in the fracture fixation of the scaphoid, as scaphoid fracture has a risk of avascular necrosis.

6.
Cureus ; 14(12): e32172, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36605058

RESUMO

INTRODUCTION: Achilles tendon is crucial for gait, and chronic Achilles tendinopathy can have a substantial impact on an individual's work and active involvement in physical or sports activity, and overall quality of life. OBJECTIVES: This research was to determine the macroscopic and microscopic anatomy of Achilles tendons in cadavers. MATERIALS AND METHODS: This experimental study was conducted in the Department of Anatomy, Saveetha Medical College, Thandalam, from March to August 2022. A total of 60 formalin-perfused cadavers (38 males and 22 females) were dissected to study their morphometry (length, width, thickness) and histology. The data was tabulated in MS excel and analyzed statistically using unpaired 't-test and one-way ANOVA in SPSS Software 17.0 (IBM Corp., Armonk, NY). RESULTS: The mean length of the Achilles tendon was significantly higher in males than in females and similarly, the length on the right side was significantly higher than on the left side (p<0.005). The width and circumference were statistically higher in females than, males whereas, the histological features were similar in both males and females. CONCLUSION: The better understanding of Achilles tendon morphometry in cadavers always aids in the diagnosis and surgical repair of tendinopathy, rupture, and degenerative change. The knowledge will be helpful for the surgeons during the repair and reconstruction of the injured tendon.

7.
Mol Biol Rep ; 45(6): 1809-1819, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30143974

RESUMO

The ubiquitously expressed protein RapGEF1 (C3G) regulates multiple cellular activities and is essential for early embryonic development in mammals. It has functions dependent on its catalytic activity as well as protein interaction domain and regulates ß-catenin signaling. This study describes the generation of a novel monoclonal antibody, 3F6mAb and its characterization for recognition of RapGEF1. Mice were immunized with recombinant protein having only the Crk binding region of RapGEF1 and hybridoma clones created by fusion of immunized spleen cells with Sp2/0 myeloma cells. This antibody recognizes human, primate and murine RapGEF1 protein. Based on the recognition of various deletion constructs, we have mapped its epitope to 580-648 amino acids. Isotyping showed that it belongs to IgG1 class of heavy chain and Kappa light chain. 3F6mAb is suitable for detecting cellular RapGEF1 by western-blotting, immunofluorescence and immunoprecipitation. It has an advantage over most of the commercially available antibodies as it can detect N- and C-terminal truncated forms of RapGEF1. Using this antibody to detect mobility shift, we show that RapGEF1 is phosphorylated on tyrosine as well as S/T residues in its Crk binding domain. This monoclonal antibody is a valuable tool that will aid in understanding functions of cellular RapGEF1.


Assuntos
Anticorpos Monoclonais/isolamento & purificação , Fator 2 de Liberação do Nucleotídeo Guanina/imunologia , Animais , Anticorpos Monoclonais/metabolismo , Western Blotting , Linhagem Celular , Epitopos , Humanos , Hibridomas , Imunoprecipitação , Camundongos , Fosforilação , Domínios Proteicos/imunologia , Engenharia de Proteínas/métodos , Domínios e Motivos de Interação entre Proteínas/imunologia , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/imunologia , Transdução de Sinais
8.
J Clin Diagn Res ; 11(5): AC01-AC04, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28658743

RESUMO

INTRODUCTION: Benign Prostatic Hyperplasia (BPH) is a common entity among men over 40 years of age with significant disability. It is a condition that occurs when the enlarged prostate gland compresses the urethra leading to Bladder Outlet Obstruction (BOO). AIM: To correlate the size of the prostate gland and uroflowmetry parameters in patients with Lower Urinary Tract Symptoms (LUTS). MATERIALS AND METHODS: One hundred and twenty randomly selected male patients, from the ages of 41 to 70 years, with LUTS, and underwent trans abdominal sonogram and uroflowmetry were included in the study. The samples were divided into three groups according to the age; Group 1: 41 to 50 years, Group 2: 51 to 60 years, Group 3: 61 to 70 years. RESULTS: In Group 1 (41 to 50 years), there were totally 28 patients with LUTS, out of which seven patients had BPH, indicating that about 5% of patients with LUTS have BPH. In Group 2 (51-60 years) there were totally 31 patients with LUTS, out of which 10 patients had BPH, indicating that 8% of patients with LUTS have BPH. In Group 3 (61-70 years) there were totally 61 patients with LUTS, out of which 33 patients had BPH, indicating that 27% of patients with LUTS had BPH. The mean age of patients with LUTS was 60 years with mean prostate size of 45 cm3. Enlarged prostate gland was present in 41% of patients with mean Q max of 14 ml/sec and post voidal volume of 48 ml. CONCLUSION: This study concludes that the LUTS in older patients are mostly due to BPH leading to BOO. Also, patients with BPH in early ages can lead to increased Post voidal Residual Volume (PVR) following uroflowmetry. Thus, screening male patients with LUTS, at 40 years and above, is an ideal way to detect prostatic problems at an early stage.

9.
Int J Syst Evol Microbiol ; 64(Pt 5): 1559-1565, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24510974

RESUMO

A novel actinomycete strain, designated VRC122T, was isolated from a Callistemon citrinus rhizosphere sample collected from New Delhi, India, and its taxonomic status was determined by using a polyphasic approach. Strain VRC122T was a Gram-stain-positive, aerobic, non-motile, non-acid-alcohol-fast strain. Phylogenetic analysis based on 16S rRNA gene sequences showed the strain was placed in a well-separated sub-branch within the genus Saccharopolyspora. The highest levels of 16S rRNA gene sequence similarity were found with Saccharopolyspora hirsuta subsp. kobensis JCM 9109T (98.71%), Saccharopolyspora antimicrobica I05-00074T (98.69%) and Saccharopolyspora jiangxiensis W12T (98.66%); 16S rRNA gene sequence similarities with type strains of all other species of the genus Saccharopolyspora were below 98%. Chemosystematic studies revealed that it contained meso-diaminopimelic acid. Arabinose and galactose were the predominant whole-cell sugars. Diagnostic polar lipids were diphosphatidylglycerol, phosphatidylinositol and phosphatidylcholine. MK-9(H6) was the predominant menaquinone. C14:0, C16:0, iso-C15:0, iso-C16:0, iso-C17:0, anteiso-C15:0, anteiso-C17:0, C17:0 cyclo and summed feature 3 (C16:1ω7c and/or C16:1ω6c) were the major cellular fatty acids. The G+C content of the genomic DNA was 69.5 mol%. The results of DNA-DNA hybridization (30%, 22% and 25%, respectively) with type strains of the above-mentioned species, in combination with differences in physiological and biochemical data supported that strain VRC122T represents a novel species of the genus Saccharopolyspora, for which the name Saccharopolyspora indica sp. nov., is proposed. The type strain is VRC122T (=KCTC 29208T=MTCC 11564T=MCC 2206T=ATCC BAA-2551T).


Assuntos
Myrtaceae/microbiologia , Filogenia , Rizosfera , Saccharopolyspora/química , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Índia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Peptidoglicano/química , RNA Ribossômico 16S/genética , Saccharopolyspora/genética , Saccharopolyspora/isolamento & purificação , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
Curr Microbiol ; 68(2): 233-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24121613

RESUMO

The diversity and abundance of culturable bacteria in Kongsfjorden water (15 stations) and sediments (12 stations) were studied. Viable numbers ranged between 105­106 CFU l−1 in water and 102­104 CFU g−1 in the sediments. A total of 291 and 43 bacterial isolates were retrieved from the water (KJF) and sediments (FS), respectively. Based on 16S rRNA gene sequence similarities, the KJF and FS isolates were grouped into 49 and 23 phylotypes, respectively. The KJF and FS phylotypes represented three phyla namely, Actinobacteria, Bacteroidetes, and Proteobacteria. At the genus level, Flavobacterium and Shewanella and at the species level, Pseudoaltermonas arctica and Colwellia psychrerythraea were dominant in the water and sediments, respectively. Most phylotypes were psychrotolerant with upper growth temperature limit of 25­37 °C and tolerated 0.3­2.5 M NaCl and pH values of 5.0­11.0. Majority of the phylotypes produced one or more of the extracellular hydrolytic enzymes amylase, lipase, caseinase, urease, gelatinase, and DNase at 4 and 18 °C, while none were chitinolytic. Few of the FS phylotypes exhibited extracellular activity only at 4 or 18 °C. Nine FS and 21 KJF isolates were pigmented. The predominant cellular fatty acids were unsaturated, branched, and modified fatty acids, which are unique to cold-adapted bacteria.


Assuntos
Bactérias/enzimologia , Biodiversidade , Estuários , Gelo , Água do Mar/microbiologia , Regiões Árticas , Bactérias/genética , Bactérias/isolamento & purificação , Carga Bacteriana , Temperatura Baixa , Ácidos Graxos/metabolismo , Sedimentos Geológicos/microbiologia , Dados de Sequência Molecular , Filogenia , Pigmentos Biológicos , RNA Ribossômico 16S
11.
Genome Announc ; 1(4)2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23950134

RESUMO

The 2.7-Mb draft genome sequence of Leifsonia rubra strain CMS 76R(T), isolated from a cyanobacterial mat sample from a pond in Wright Valley, McMurdo, Antarctica, is reported.

12.
Int J Syst Evol Microbiol ; 63(Pt 12): 4374-4379, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23838447

RESUMO

A facultatively anaerobic, alkaliphilic, Gram-stain-positive, rod-shaped bacterium, designated strain 12/1(T), isolated from alkaline wastewater drained sludge of a beverage industry facility located near New Delhi, India, was subjected to a polyphasic taxonomic study. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain 12/1(T) belonged to the genus Exiguobacterium and was most closely related to Exiguobacterium aurantiacum DSM 6208(T) (99.46 %), E. aquaticum IMTB-3094(T) (99.18 %), E. mexicanum 8N(T) (99.06 %), E. profundum 10C(T) (98.17 %), E. aestuarii TF-16(T) (98.1 %) and E. marinum TF-80(T) (98.03 %). The DNA G+C content of strain 12/1(T) was 55.6 mol%, major respiratory isoprenoid quinone was MK-7, major polar lipids were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine and the cell-wall peptidoglycan was of the A3α l-Lys-Gly type, characteristics consistent with its affiliation to the genus Exiguobacterium. Strain 12/1(T) showed levels of DNA-DNA hybridization of less than 70 % with the closely related species of the genus Exiguobacterium. Overall, the phenotypic, chemotaxonomic and phylogenetic data presented in this study suggest that strain 12/1(T) represents a novel species of the genus Exiguobacterium, for which the name Exiguobacterium alkaliphilum sp. nov. is proposed. The type strain is 12/1(T) ( = CCM 8459(T) = DSM 21148(T)).


Assuntos
Bacillaceae/classificação , Bebidas , Filogenia , Águas Residuárias/microbiologia , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Indústria Alimentícia , Índia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Peptidoglicano/química , RNA Ribossômico 16S/genética , Esgotos/microbiologia , Vitamina K 2/análogos & derivados , Vitamina K 2/química
13.
Genome Announc ; 1(4)2013 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-23846277

RESUMO

The 4.69-Mb genome sequence of Arcticibacter svalbardensis strain MN12-7(T), isolated from an Arctic soil sample, is reported.

14.
Genome Announc ; 1(3)2013 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-23766406

RESUMO

Here, we report the 3.2-Mbp draft genome sequence of Bhargavaea cecembensis strain DSE10(T), isolated from a sediment sample collected from the Chagos-Laccadive ridge system in the Indian Ocean at a depth of 5,904 m.

15.
Genome Announc ; 1(3)2013 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-23682146

RESUMO

Here we report the 4.75-Mb genome of Cesiribacter andamanensis strain AMV16(T), isolated from a soil sample from a mud volcano in the Andaman Islands, India.

16.
Int J Syst Evol Microbiol ; 63(Pt 5): 1627-1632, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22904219

RESUMO

In the course of a study aimed at isolating bacteria from Arctic soils by a method that selectively enriches for rare bioactive actinomycetes, a Gram-stain-negative, pigmented, non-motile rod, designated MN12-7(T), was isolated. The salmon-pink strain was, based on 16S rRNA gene sequence similarity, found to be affiliated with the family Sphingobacteriaceae. Strain MN12-7(T) was catalase-, oxidase- and cellulase-positive and lacked gelatinase, urease, lipase and pectinase. The predominant cellular fatty acids were summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c), iso-C15 : 0 and C15 : 1ω6c. The major respiratory quinone of strain MN12-7(T) was MK-7, and the major polar lipid was phosphatidylethanolamine in addition to phosphatidylserine, seven unidentified lipids and six unidentified aminolipids. The DNA G+C content of strain MN12-7(T) was 38 mol%. Strain MN12-7(T) formed a separate lineage in a cluster containing 'Candidatus comitans', with which it shared 92.3 % 16S rRNA gene sequence similarity. Based on the phenotypic characteristics and phylogenetic inference, strain MN12-7(T) is proposed as a representative of a novel species in a new genus, Arcticibacter svalbardensis gen. nov., sp. nov. The type strain of the type species is MN12-7(T) ( = KCTC 32015(T) = CIP 110422(T)).


Assuntos
Bacteroidetes/classificação , Filogenia , Microbiologia do Solo , Regiões Árticas , Técnicas de Tipagem Bacteriana , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Dados de Sequência Molecular , Fosfatidiletanolaminas/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Svalbard , Vitamina K 2/análogos & derivados , Vitamina K 2/análise
17.
Res Microbiol ; 164(1): 70-82, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23041141

RESUMO

Culturable bacterial abundance at 11 different depths of a 50.26 m ice core from the Tallaksenvarden Nunatak, Antarctica, varied from 0.02 to 5.8 × 10(3) CFU ml(-1) of the melt water. A total of 138 bacterial strains were recovered from the 11 different depths of the ice core. Based on 16S rRNA gene sequence analyses, the 138 isolates could be categorized into 25 phylotypes belonging to phyla Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria. All isolates had 16S rRNA sequences similar to previously determined sequences (97.2-100%). No correlation was observed in the distribution of the isolates at the various depths either at the phylum, genus or species level. The 25 phylotypes varied in growth temperature range, tolerance to NaCl, growth pH range and ability to produce eight different extracellular enzymes at either 4 or 18 °C. Iso-, anteiso-, unsaturated and saturated fatty acids together constituted a significant proportion of the total fatty acid composition.


Assuntos
Bactérias/classificação , Biodiversidade , Gelo/análise , Microbiologia da Água , Adaptação Fisiológica , Regiões Antárticas , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Carga Bacteriana , Enzimas/metabolismo , Ácidos Graxos , Congelamento , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
18.
Curr Microbiol ; 66(1): 64-71, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23053490

RESUMO

The abundance and diversity of chemotactic heterotrophic bacteria associated with Arctic cyanobacteria was determined. The viable numbers ranged between 10(4) and 10(6) cell g(-1) cyanobacterial biomass. A total of 112 morphotypes, representing 22 phylotypes based on their 16S rRNA sequence similarity were isolated from the samples. All the phylotypes were Gram-negative with affiliation to the proteobacterial and bacteroidetes divisions. Among the 22 phylotypes, 14 were chemotactic to glucose. Majority of the phylotypes were psychrotolerant showing growth up to 30 °C. Representatives of Alphaproteobacteria, the genus Flavobacterium and the gammaproteobacterial Alcanivorax sp, were psychrophilic with growth at or below 18 °C. A significant percentage of phylotypes were pigmented (~68 %), rich in unsaturated membrane fatty acids and tolerated pH values and NaCl concentrations between 5.0-8.0 and 0.15-1.0 M, respectively. The percentages of phylotypes producing extracellular cold-active enzymes at 4 °C were amylase (18.18 %), lipase and urease (45.45 %), caseinase (59.09 %) and gelatinase (31.8 %).


Assuntos
Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Fenômenos Fisiológicos Bacterianos , Biodiversidade , Quimiotaxia , Microbiologia Ambiental , Processos Heterotróficos , Regiões Árticas , Bactérias/genética , Bactérias/isolamento & purificação , Carga Bacteriana , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Viabilidade Microbiana , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Int J Syst Evol Microbiol ; 62(Pt 9): 2133-2139, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22039004

RESUMO

A novel Gram-stain-negative, horseshoe-shaped, non-motile bacterium, designated strain M12-11B(T), was isolated from a marine sediment sample collected at a depth of 200 m from Kongsfjorden, Svalbard. The colony colour was orangish red due to the presence of carotenoids. Fatty acids were dominated by branched and unsaturated fatty acids (90.8 %), with a high abundance of iso-C(15 : 0) (14.9 %), anteiso-C(15 : 0) (11.4 %), iso-C(15 : 1) G (13.1 %), C(15 : 1)ω6c (5.4 %), C(17 : 1)ω6c (6.7 %), summed feature 3 (C(16 : 1)ω7c and/or C(16 : 1)ω6c; 9.3 %) and summed feature 9 (10-methyl C(16 : 0) and/or iso-C(17 : 1)ω9c; 5.9 %). Strain M12-11B(T) contained MK-7 as the major respiratory quinone. The polar lipids consisted of phosphatidylcholine, phosphatidylethanolamine, one unidentified aminolipid and three unidentified lipids. Based on 16S rRNA gene sequence similarities, the type strains of Cyclobacterium amurskyense, Cyclobacterium marinum and Cyclobacterium lianum were most closely related to M12-11B(T) with sequence similarities of 98.2, 96.8 and 93.3 %, respectively. Other members of the family Cyclobacteriaceae had sequence similarities of <92.0 %. However, DNA-DNA hybridization with Cyclobacterium amurskyense KCTC 12363(T) and Cyclobacterium marinum DSM 745(T) showed relatedness values of only 24.5 and 32.5 % with respect to strain M12-11B(T). Based on the results of DNA-DNA hybridization experiments and phenotypic and chemotaxonomic data, it appears that strain M12-11B(T) represents a novel species of the genus Cyclobacterium, for which the name Cyclobacterium qasimii sp. nov. is proposed; the type strain is M12-11B(T) (= KCTC 23011(T) = NBRC 106168(T)) and it has a DNA G+C content of 40.5 mol%.


Assuntos
Cytophagaceae/classificação , Filogenia , Água do Mar/microbiologia , Microbiologia da Água , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , Cytophagaceae/genética , Cytophagaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/análise , Sedimentos Geológicos/microbiologia , Dados de Sequência Molecular , Quinonas/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Svalbard
20.
Curr Microbiol ; 60(4): 307-14, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19967375

RESUMO

A total of 132 yeast strains were characterised from 4 sediment samples collected from small puddles in the vicinity of Midre Lovénbreen glacier, Arctic. Based on the D1/D2 domain sequence similarity, the isolates could be categorised into 6 groups. The nearest phylogenetic neighbour of groups I to VI were identified as Cryptococcus gastricus, Cryptococcus terricolus, Rhodotorula muscorum, Mrakia psychrophila, Mrakia gelida and Rhodotorula glacialis, respectively. Strains representative of the six groups were psychrophilic and salt tolerant but varied in their ability to produce cold-active extracellular enzymes such as lipase, protease, pectinase, cellulase and amylase. C(18:1 (w9C)) and C(18:2 (w9,12C)) were the only two fatty acids common to all the yeasts and branched and (or) unsaturated fatty acids increased in yeasts growing at 8 degrees C compared to 22 degrees C, probably as an adaptation to low temperature. The present study establishes that psychrophilic yeasts are predominant in Arctic and could be used as work horses to produce cold-active enzymes and poly unsaturated fatty acids which have been implicated in low temperature adaptation and also for their use in biotechnology.


Assuntos
Enzimas/isolamento & purificação , Ácidos Graxos/isolamento & purificação , Proteínas Fúngicas/isolamento & purificação , Microbiologia da Água , Leveduras/classificação , Leveduras/isolamento & purificação , Regiões Árticas , Temperatura Baixa , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Dados de Sequência Molecular , Filogenia , RNA Ribossômico/genética , Análise de Sequência de DNA , Leveduras/química , Leveduras/genética
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