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101.

Background  

Brucellosis is primarily a zoonotic disease caused by Brucella species. There are currently ten Brucella spp. including the recently identified novel B. inopinata sp. isolated from a wound associated with a breast implant infection. In this study we report on the identification of an unusual Brucella-like strain (BO2) isolated from a lung biopsy in a 52-year-old patient in Australia with a clinical history of chronic destructive pneumonia.  相似文献   
102.
The cephalochordate, amphioxus, is phylogenetically placed at the most primitive position in the chordate clade. Despite many studies on the endocrine system of amphioxus, definitive evidence has not been reported for the presence an endocrine system comparable to the pituitary-gonadal axis, which is important in the regulation of reproduction in vertebrates. Recent genome analyses in the amphioxus, Branchiostoma floridae, showed that it does not have any pituitary hormone genes except the thyrostimulin gene. Thyrostimulin is a heterodimeric glycoprotein hormone consisting of α and β subunits, and is present in various organs of vertebrates. Analyses of a phylogenetic tree and a synteny suggest that amphioxus' thyrostimulin is an ancestral type of the glycoprotein hormones in chordates. In addition, genes for sex steroidogenic enzymes belonging to the CYP family were found in the genome sequences. The conversion pathway of sex steroids from cholesterol to estrogen, androgen, and major sex steroids was also identified in the gonads of amphioxus in vitro. Furthermore, we demonstrated the expression of genes encoding thyrostimulin and sex steroidogenic enzymes by an in situ hybridization technique. Here, we discuss the evolution of hormones and reproductive functions in the neuroendocrine control system of chordates.  相似文献   
103.
Multidimensional LC-MS based shotgun proteomics experiments at the peptide level have traditionally been carried out by ion exchange in the first dimension and reversed-phase liquid chromatography in the second. Recently, it has been shown that isoelectric focusing (IEF) is an interesting alternative approach to ion exchange separation of peptides in the first dimension. Here we present an improved protocol for peptide separation by continuous free-flow electrophoresis (FFE) as the first dimension in a two-dimensional peptide separation work flow. By the use of a flat pI gradient and a mannitol and urea based separation media we were able to perform high-throughput proteome analysis with improved interfacing between FFE and RPLC-MS/MS. The developed protocol was applied to a cytosolic fraction from Schneider S2 cells from Drosophila melanogaster, resulting in the identification of more than 10,000 unique peptides with high probability. To improve the accuracy of the peptide identification following FFE-IEF we incorporated the pI information as an additional parameter into a statistical model for discrimination between correct and incorrect peptide assignments to MS/MS spectra.  相似文献   
104.
Phytases catalyze the hydrolysis of phytic acid (myo-inositol hexakisphosphate), the most abundant inositol phosphate in cells. Phytases are of great commercial importance because their use as food and animal feed supplement has been approved by many countries to alleviate environmental and nutritional problems. Although acid phytases have been extensively studied, information regarding alkaline phytases is limited. Alkaline phytases with unique catalytic properties have been identified in plants, however, there is no report on the purification or structural properties. In this paper, we describe the purification of alkaline phytase from plant tissue. The purification was challenging because of contamination from non-specific phosphatases and acid phytases and low endogenous concentration. The purification of alkaline phytase from pollen grains of Lilium longiflorum involved selective precipitation by heat and ammonium sulfate followed by anion exchange and chromatofocusing chromatography and, finally, gel electrophoresis. Alkaline phytase was purified approximately 3000-fold with an overall recovery of 4.2%. The native molecular mass was estimated to be in the range of 118+/-7 kDa by Ferguson plot analysis and Mr of denatured protein in the range of 52-55 kDa by SDS-PAGE suggesting that the enzyme is a homodimer. Separation by 2-D gel and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometric analysis of separated proteins indicates the presence of multiple mass and charge isoforms with pI values between 7.3 and 8.3. To our knowledge, this is the first alkaline phytase to be purified from plant sources. The unique properties suggest that the enzyme has the potential to be useful as a feed and food supplement.  相似文献   
105.
Microsatellite diversity was analyzed in four Proto-Australoid tribes, including Indo-European (Marathi)-speaking Katkari, Pawara, Mahadeo-Koli, and Dravidian (Gondi)-speaking groups of Maharashtra, west-central India, to understand their genetic structure and to identify the congruence between language and gene pool. Allele frequency data at 15 short tandem repeat (STR) loci in studied tribes was compared with data of 22 Indo-European- and Dravidian-speaking caste and tribal populations using heterozygosity, allele size variance, analysis of molecular variance (AMOVA), G(ST) estimate, PC plot, and Mantel correlation test. Our results demonstrate that "Gondi" tribes comprising the Madia-Gond, a hunter-gatherer population, and the agriculturist Dheria-Gond harbor lower diversity than "Marathi" tribal groups, which are culturally and genetically distinct. Katkari, a hunter-gatherer tribe, showed greater diversity and the presence of a large number of unique alleles, genetically distinct from all others except the Pawara, supporting their old cultural links. The agriculturist Pawara tribe represents a splinter subgroup of the Bhil tribe and has experienced gene flow. The Mahadeo-Koli, an agriculturally oriented tribe, displayed significant heterozygote deficiency, attributable to the practice of high endogamy. The Proto-Australoid tribal populations were genetically differentiated from castes of similar morphology, suggesting different evolutionary mechanisms operating upon the populations. The populations showed genetic and linguistic similarity, barring a few groups with varied migratory histories. The microsatellite variation clearly demonstrates the interplay of sociocultural factors including linguistic, geographical contiguity, and microevolutionary processes in shaping the genetic diversity of populations in contemporary India. This study supports the ethno-historical relationships of Indian populations.  相似文献   
106.
Corneal scarring is a major cause of blindness worldwide and can result from the deposition of abnormal amounts of collagen fibers lacking the correct size and spacing required to produce a clear cornea. Collagen fiber formation requires a preformed fibronectin (FN) matrix. We demonstrate that the loss of syndecan1 (sdc1) in corneal stromal cells (CSC) impacts cell migration rates, the sizes and composition of focal and fibrillar adhesions, the activation of integrins, and the assembly of fibronectin into fibrils. Integrin and fibronectin expression are not altered on sdc1-null CSCs. Cell adhesion, spreading, and migration studies using low compared to high concentrations of FN and collagen I (CNI) or vitronectin (VN) with and without activation of integrins by manganese chloride show that the impact of sdc1 depletion on integrin activation varies depending on the integrin-mediated activity evaluated. Differences in FN fibrillogenesis and migration in sdc1-null CSCs are reversed by addition of manganese chloride but cell spreading differences remain. To determine if our findings on sdc1 were specific to the cornea, we compared the phenotypes of sdc1-null dermal fibroblasts with those of CSCs. We found that without sdc1, both cell types migrate faster; however, cell-type-specific differences in FN expression and its assembly into fibrils exist between these two cell types. Together, our data demonstrate that sdc1 functions to regulate integrin activity in multiple cell types. Loss of sdc1-mediated integrin function results in cell-type specific differences in matrix assembly. A better understanding of how different cell types regulate FN fibril formation via syndecans and integrins will lead to better treatments for scarring and fibrosis.  相似文献   
107.
Bamboos are a diverse and ecologically important group of plants that have the potential to modulate the structure, composition, and function of forests. With the aim of increasing the visibility and representation of bamboo in forest surveys, and to standardize techniques across ecosystems, we present a protocol for bamboo monitoring in permanent research plots. A bamboo protocol is necessary because measurements and sampling schemes that are well-suited to trees are inadequate for monitoring most bamboo species and populations. Our protocol suggests counting all bamboo culms (stems) in the study plot and determining bamboo dimensions based on two different approaches: (a) measuring a random subset of 60 culms and calculating the average dimensions or (b) measuring all culms. With data from 1-ha plots in the Peruvian Andes, we show that both approaches provide very similar estimates of bamboo basal area. We suggest including all mature culms rooted inside change the to each plot from all woody bamboo species with maximum diameters ≥1 cm. We also present recommendations on how to collect vouchers of bamboo species for identification. Data collected according to our proposed protocols will increase our understanding of regional and global patterns in bamboo diversity and the role of bamboo in forest dynamics.  相似文献   
108.
Demonstrating the effectiveness of expensive new rheumatoid arthritis (RA) therapeutics is imperative to determine whether the quality of care has improved with the introduction of these agents. Our current RA quality measures are primarily process based, but they must become outcomes based to better demonstrate quality. New RA quality measures must be multidimensional, accounting for all of the important outcomes in RA: radiographic, functional status, and disease activity. To fully understand the potential benefits of new therapeutics in RA, outcome measures must be integrated with routine practice.New medications for rheumatoid arthritis (RA), combined with early, aggressive treatment strategies, have improved care. New biologic and small molecule therapies come with a hefty price tag, and demonstrating effectiveness is increasingly important: is the quality of care actually better for RA patients with newer therapies?To answer this question, we must first define quality. As described by the Institute of Medicine, quality of care is ''the degree to which healthcare services for individuals and populations increase the likelihood of desired health outcomes and are consistent with current professional knowledge’ [1]. Quality of care can be evaluated using quality measures, which are tools that provide the ability to quantify an aspect of healthcare relative to an established criterion [2]. Other facets of quality include patient satisfaction and access to care. Quality of care in RA is currently largely based on the use of process-based quality measures. For example: the frequency of disease-modifying anti-rheumatic drug (DMARD) prescribing in RA; the use of disease activity and functional status measures in routine practice; and laboratory monitoring frequency according to established recommendations. These RA quality measures are primarily derived from the Arthritis Foundation Starter Set and the Physician Quality Reporting Database RA measure set, but the American College of Rheumatology is actively developing a new RA measure set [3]. Although the current RA quality measures provide a reasonable starting point, they do not fully capture the spectrum of care quality for patients with RA in the United States.Measures of quality of care are evolving to include concepts such as clinical outcomes. Some even argue that our primary goal should be to provide value: the health outcomes achieved per dollar spent [4]. This newer model incorporates the total cost of providing care to patients for a specific condition over a defined time period, relative to the health outcome achieved. For example, in RA the total cost of care would include nonbiologic and biologic DMARDs, office visits, physical therapy and inpatient hospitalizations. But the real question is how to best define outcomes in a chronic, complex condition such as RA? Outcomes can be multidimensional, accounting for all facets of care for a RA patient: radiographic progression, improvement in functional status score, or a decrease in disease activity score. Radiographic progression is often discussed as an important outcome in randomized controlled trials of RA therapeutics, but it is not a routine part of clinical practice. Measurement of functional status using a standardized, validated instrument is an important patient-reported outcome, capturing key information about how RA impacts activities of daily living. Patient-reported outcomes are not used regularly in many busy, office practices despite the correlation with disease outcomes and mortality [5,6].While professional groups such as the American College of Rheumatology have made recommendations on the measurement of disease activity through the use of tools such as the Disease Activity Score-28, the Clinical Disease Activity Index, or the Routine Assessment of Patient Disease Activity 3, documenting sustained low disease activity or remission requires multiple measurements [7]. Encouraging rheumatologists to treat to target and moving patients from high disease activity to remission is just one dimension of RA outcomes. Each potential clinical outcome has strengths and limitations and probably cannot serve as a standalone measure, but taken together they provide a more nuanced portrait of RA quality of care.Moving from thinking about quality measures as process based to outcomes based is a significant challenge. To achieve good outcomes in RA using the new therapeutics in RA, one needs to consider the timing of therapy, the duration of treatment, and the co-existence of other medical conditions. Some patients may delay initiation of DMARD therapy due to fear of toxicity or lack of understanding of the risk/benefit profile; other patients may not be fully adherent to the treatment plan due to financial issues, socioeconomic factors or language barriers; and still others may not have access to rheumatology care until after they have sustained radiographic or functional damage from their RA. Since quality is often measured at the level of the rheumatologist, how do we risk adjust for these complex patient-related factors when evaluating outcomes in RA? Some rheumatologists see tertiary-care referral patients with longer disease duration, more treatment failures, and multiple co-morbidities. Developing appropriate case-mix adjustment tools to allow for meaningful comparison across providers is a huge task. We have learned that even for a simple quality measure such as whether RA patients receive a DMARD, this case-mix adjustment matters. When evaluating the quality measure on receipt of DMARDs for patients with RA, case-mix adjustment identified age, race and socioeconomic status as negative predictors of DMARD receipt [8].Even though the road will be tough, we must determine how to best measure outcomes in RA to assess quality of care. The expenditures associated with biologic treatments raise important questions for how to demonstrate the effectiveness of medications for RA. However, there are emerging data on RA patients remaining in remission with fewer doses or even cessation of biologic drugs, raising the possibility that we can improve value for patients by simultaneously achieving good health outcomes and decreasing the overall cost of care [9]. An important first step to showing that new therapeutics are translating into better quality of care is incorporating the use of quantitative measurement of disease activity and functional status into routine clinical practice. By regularly measuring possible RA outcome measures, such as disease activity and functional status, we can identify patients who are achieving poor outcomes and create strategies to re-design care delivery for those patients. For example, the use of intensive nurse outreach between regularly scheduled rheumatologist visits to document medication adherence, side effects and education may improve outcomes faster and facilitate treating to target. Developing clinical risk-adjustment tools for RA can help offset differences in patient case mix among rheumatologists.However, measuring outcomes presents major challenges for the healthcare system in general. Collecting structured data to allow quality assessment is not routine in many practices and would place new burdens on the already stressed healthcare system, adding costs and frustration. Furthermore, accurately assessing quality of care requires adjusting for case-mix severity. This is especially true if outcomes become the focus of quality assessment. Collecting the dataset required for case-mix adjustment further taxes the healthcare provider. In addition, there are unanswered questions that remain: what is the current natural history of RA if diagnosed early and treated aggressively with combination nonbiologic and biologic DMARDs? To fully achieve the potential benefits of new therapeutics in RA, we first need RA quality measures that incorporate outcomes and these need to be easily integrated into typical practice.  相似文献   
109.
Polyproline II (PPII) fold, an unusual structural element was detected in the serine protease from Nocardiopsis sp. NCIM 5124 (NprotI) based on far UV circular dichroism spectrum, structural transitions of the enzyme in presence of GdnHCl and a distinct isodichroic point in chemical and thermal denaturation. The functional activity and conformational transitions of the enzyme were studied under various denaturing conditions. Enzymatic activity of NprotI was stable in the vicinity of GdnHCl upto 6.0 M concentration, organic solvents viz. methanol, ethanol, propanol (all 90% v/v), acetonitrile (75% v/v) and proteases such as trypsin, chymotrypsin and proteinase K (NprotI:protease 10:1). NprotI seems to be a kinetically stable protease with a high energy barrier between folded and unfolded states. Also, an enhancement in the activity of the enzyme was observed in 1 M GdnHCl upto 8 h, in organic solvents (75% v/v) for 72 h and in presence of proteolytic enzymes. The polyproline fold remained unaltered or became more prominent under the above mentioned conditions. However, it diminished gradually during thermal denaturation above 60 °C. Thermal transition studies by differential scanning calorimetry (DSC) showed scan rate dependence as well as irreversibility of denaturation, the properties characteristic of kinetically stable proteins. This is the first report of PPII helix being the global conformation of a non structural protein, an alkaline serine protease, from a microbial source, imparting kinetic stability to the protein.  相似文献   
110.

Objective

Central (truncal) adiposity is associated strongly with insulin resistance and diabetes. There are very few reports comparing methods of trunk fat measurement in their ability to predict glycaemia and insulin resistance. We report a comparative analysis of different trunk fat measurements in predicting glycaemia and insulin resistance in middle aged Indian men.

Materials and Methods

Trunk fat measurements were performed using anthropometry, magnetic resonance imaging (MRI), dual-energy X-ray absorptiometry (DXA) and computed tomography (CT) on 128 men. Additional measurements were taken to characterise insulin resistance (Matsuda index) and beta cell function (Insulinogenic Index), glycaemia (fasting and 120 min glucose concentrations). Using residual approach we compared the ability of different trunk fat measurement techniques to predict insulin resistance, beta cell function and glycaemia.

Results

There was a strong association between trunk fat measures from each technique with glycaemia and insulin resistance indices but not with the Insulinogenic Index. Insulin resistance and glycaemia, were best predicted using anthropometric measurements, notably by waist circumference and subscapular skinfold thickness. Neither MRI measures of trunk or visceral fat nor DXA trunk fat added significantly. CT liver density contributed to some extent to predict insulin resistance and 120 min glucose after anthropometric measurements.

Conclusions

Our results suggest that, in Indian men, anthropometric measurements are good predictors of glycaemia and insulin resistance. Other complex measurements such as MRI, DXA and CT make only a small addition to the prediction. This finding supports the application of anthropometry for determining trunk fat in clinical and epidemiological settings.  相似文献   
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