Simultaneous determination of trace marine lipophilic and hydrophilic phycotoxins in various environmental and biota matrices.

An efficient and sensitivity approach, which combines solid-phase extraction or ultrasonic extraction for pretreatment, followed by ultra-performance liquid chromatography-tandem mass spectrometry, has been established to simultaneously determine eight lipophilic phycotoxins and one hydrophilic phycotoxin in seawater, sediment and biota samples. The recoveries and matrix effects of target analytes were in the range of 61.6-117.3 %, 55.7-121.3 %, 57.5-139.9 % and 82.6 %-95.0 %, 85.8-106.8 %, 80.7 %-103.3 % in seawater, sediment, and biota samples, respectively. This established method revealed that seven, six and six phycotoxins were respectively detected in the Beibu Gulf, with concentrations ranging from 0.14 ng/L (okadaic acid, OA) to 26.83 ng/L (domoic acid, DA) in seawater, 0.04 ng/g (gymnodimine-A, GYM-A) to 2.75 ng/g (DA) in sediment and 0.01 ng/g (GYM-A) to 2.64 ng/g (domoic acid) in biota samples. These results suggest that the presented method is applicable for the simultaneous determination of trace marine lipophilic and hydrophilic phycotoxins in real samples.

Differential Impairment of Thalamocortical Structural Connectivity in Amyotrophic Lateral Sclerosis.

AIMS: The thalamus is a major relay station that modulates input from many cortical areas and a filter for sensory input and is involved in the pathophysiology of amyotrophic lateral sclerosis (ALS). However, it still remains unclear whether all thalamocortical networks are affected or whether there is selective vulnerability. In this study, we aimed to study the selective vulnerability of different thalamocortical structural connections in ALS and to test the hypothesis of a specific impairment in motor-related thalamocortical connectivity. METHODS: Diffusion tensor imaging (DTI) tractography was used to identify thalamocortical structural pathways in 38 individuals with ALS and 35 gender/age-matched control subjects. Thalami of both groups were parcellated into subregions based on local patterns of thalamocortical connectivity. DTI measures of these distinct thalamocortical connections were derived and compared between groups. RESULTS: The analysis of probabilistic tractography showed that the structural connectivity between bilateral pre/primary motor cortices and associated thalamic subregions was specifically impaired in patients with ALS, while the other thalamocortical connections remained relatively intact. In addition, fractional anisotropy values of the impaired thalamocortical motor pathway were inversely correlated with the disease duration. CONCLUSION: Our findings provide direct evidence for selective impairment of the thalamocortical structural connectivity in ALS.

Artificial induction of genetic competence in Bacillus amyloliquefaciens isolates.

OBJECTIVES: To induce natural genetic competence in Bacillus amyloliquefaciens isolates through overexpression of the master regulator, ComK, from B. subtilis (ComK Bsu ). RESULTS: Plasmid pUBXC carrying the xylose-inducible comK expression cassette was constructed using plasmid pUB110 as a backbone. Plasmid pUBXC could be transferred from B. subtilis to B. amyloliquefaciens through plasmid pLS20-mediated biparental conjugation. After being induced by xylose, four B. amyloliquefaciens strains harbouring plasmid pUBXC developed genetic competence. Under optimal conditions, the transformation efficiencies of plasmid DNA ranged from 129 ± 20.6 to 1.7 ± 0.1 × 105 cfu (colony-forming units) per µg DNA, and the transformation efficiencies of PCR-assembled deletion constructs ranged from 3.2 ± 0.76 to 3.5 ± 0.42 × 104 cfu per µg DNA in the four tested strains. CONCLUSION: Artificial induction of genetic competence through overexpressing ComK Bsu in B. amyloliquefaciens completed the tasks of replicative plasmid delivery and gene knockout via direct transformation of PCR-generated deletion cassettes.

The complete mitochondrial genome of black-footed ferret, Mustela nigripes (Mustela, Mustelinae).

In this study, the complete mitochondrial genome sequence of black-footed ferret, Mustela nigripes, is determined for the first time. This mitogenome is 16,556 bp in length and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 control region (D-loop). The overall base composition is A (32.9%), C (26.1%), G (13.8%), and T (27.2%), so the percentage of A and T (60.1%) is higher than that of G and C. Most of the genes are encoded on H-strand, except for the ND6 subunit gene and six tRNA genes. The complete mitochondrial genome sequence reported here would be useful for further phylogenetic analysis and conservation genetic studies in M. nigripes.

Amplitude of low-frequency oscillations in Parkinson's disease: a 2-year longitudinal resting-state functional magnetic resonance imaging study.

BACKGROUND: Neuroimaging studies have found that functional changes exist in patients with Parkinson's disease (PD). However, the majority of functional magnetic resonance imaging (fMRI) studies in patients with PD are task-related and cross-sectional. This study investigated the functional changes observed in patients with PD, at both baseline and after 2 years, using resting-state fMRI. It further investigated the relationship between whole-brain spontaneous neural activity of patients with PD and their clinical characteristics. METHODS: Seventeen patients with PD underwent an MRI procedure at both baseline and after 2 years using resting-state fMRI that was derived from the same 3T MRI. In addition, 20 age- and sex-matched, healthy controls were examined using resting-state fMRI. The fractional amplitude of low-frequency fluctuation (fALFF) approach was used to analyze the fMRI data. Nonlinear registration was used to model within-subject changes over the scanning interval, as well as changes between the patients with PD and the healthy controls. A correlative analysis between the fALFF values and clinical characteristics was performed in the regions showing fALFF differences. RESULTS: Compared to the control subjects, the patients with PD showed increased fALFF values in the left inferior temporal gyrus, right inferior parietal lobule (IPL) and right middle frontal gyrus. Compared to the baseline in the 2 years follow-up, the patients with PD presented with increased fALFF values in the right middle temporal gyrus and right middle occipital gyrus while also having decreased fALFF values in the right cerebellum, right thalamus, right striatum, left superior parietal lobule, left IPL, left precentral gyrus, and left postcentral gyrus (P < 0.01, after correction with AlphaSim). In addition, the fALFF values in the right cerebellum were positively correlated with the Unified PD Rating Scale (UPDRS) motor scores (r = 0.51, P < 0.05, uncorrected) and the change in the UPDRS motor score (r = 0.61, P < 0.05, uncorrected). CONCLUSIONS: The baseline and longitudinal changes of the fALFF values in our study suggest that dysfunction in the brain may affect the regions related to cortico-striato-pallido-thalamic loops and cerebello-thalamo-cortical loops as the disease progresses and that alterations to the spontaneous neural activity of the cerebellum may also play an important role in the disease's progression in patients with PD.

[A study of 152 cases of pulmonary fungal infection: reevaluation of the microbiological spectra].

OBJECTIVE: To investigate the microbiological spectra and clinical outcome of patients with pulmonary fungal infections. METHODS: All the cases of clinically diagnosed pulmonary fungal infection from January 2002 to June 2006 were reevaluated according to the definitions of European Organization for Research and Treatment of Cancer/National Institute of Allergy and Infectious Diseases Mycosis Study Group (EORTC/MSG), and the etiology of the patients were analyzed. RESULTS: Pulmonary fungal disease was classified as proven (n = 38), probable (n = 24), possible (n = 35) and colonization (n = 55). In the proven group, the most frequently encountered fungi were Aspergillus species (15/38), followed by Cryptococcus species (13/38), Candida species were rare (2/38). In the probable group, Aspergillus species and Aspergillus species + Candida species were among the most common pathogens; while in the possible group and the colonization group, Candida species were most frequently encountered. The mortality of patients with probable pulmonary fungal infection (58.3%) was higher than that of patients in the possible group (25.7%) or the colonization group (16.4%) (P = 0.001). Univariate analysis showed that only APACHE II score was associated with outcome of patients with "pulmonary Candida infections", and antifungal therapy did not improve the outcome of such patients. CONCLUSION: The most frequently encountered fungi in patients with pulmonary fungal infections were Aspergillus species, followed by Cryptococcus species. Primary Candida pulmonary infections were rare.