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Bacillus thuringiensis is a Gram-positive entomopathogenic bacterium that produces different pesticidal proteins: vegetative insecticidal proteins (Vpb1/Vpa2, Vip3, and Vpb4) during vegetative growth, which are secreted to the culture medium, and δ-endotoxins (Cry and Cyt) during sporulation, which accumulate into parasporal crystals. Cyt proteins are the smaller subset of δ-endotoxins targeting Diptera species. While Cry and Vip3 proteins undergo positive selection, our analysis suggests that Cyt proteins evolve following a conservative trend driven negative (purifying) selection.

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Bacillus thuringiensis is a Gram-positive bacterium known for its insecticidal proteins effective against various insect pests. However, limited strains and proteins target coleopteran pests like Anthonomous grandis Boheman, causing substantial economic losses in the cotton industry. This study focuses on characterizing a Bacillus sp. strain, isolated from Oncativo (Argentina), which exhibits ovoid to amorphous parasporal crystals and was designated Bt_UNVM-84. Its genome encodes genes for the production of two pairs of binary Vpb1/Vpa2 proteins and three Cry-like proteins showing similarity with different Cry8 proteins. Interestingly, this gene content was found to be conserved in a previously characterized Argentine isolate of B. thuringiensis designated INTA Fr7-4. SDS-PAGE analysis revealed a major band of 130 kDa that is proteolytically processed to an approximately 66-kDa protein fragment by trypsin. Bioassays performed with spore-crystal mixtures demonstrated an interesting insecticidal activity against the cotton boll weevil A. grandis neonate larvae, resulting in 91% mortality. Strain Bt_UNVM-84 is, therefore, an interesting candidate for the efficient biological control of this species, causing significant economic losses in the cotton industry in the Americas.

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BACKGROUND: Rapid advances in neuroimaging technologies in the exploration of the living human brain also apply to movement disorders. However, the accurate diagnosis of Parkinson's disease (PD) and atypical parkinsonian disorders (APDs) still remains a challenge in daily practice. METHODS: We review the literature and our own experience as the Movement Disorder Society-Neuroimaging Study Group in Movement Disorders with the aim of providing a practical approach to the use of imaging technologies in the clinical setting. RESULTS: The enormous amount of articles published so far and our increasing recognition of imaging technologies contrast with a lack of imaging protocols and updated algorithms for differential diagnosis. The distinctive pathological involvement in different brain structures and the correlation with imaging findings obtained with magnetic resonance, positron emission tomography, or single-photon emission computed tomography illustrate what qualitative and quantitative measures may be useful in the clinical setting. CONCLUSION: We delineate a pragmatic approach to discuss imaging technologies, updated imaging algorithms, and their implications for differential diagnoses in PD and APDs.

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BACKGROUND: The long-term impact of deep brain stimulation (DBS) on Parkinson's disease (PD) is difficult to assess and has not yet been rigorously evaluated in comparison to its natural history. OBJECTIVE: Comparison of key disability milestones (recurrent falls, psychosis, dementia, and institutionalization) and death in patients with PD with versus without DBS. METHODS: We collected retrospective information from clinical notes of patients with PD at our center that were implanted with subthalamic DBS >8 years ago (1999-2010) and a control group of PD patients without DBS similar in age at onset, age at baseline, sex distribution, and number of comorbidities at baseline (extracted from a registry study performed in 2004). Cox regression models were used to calculate hazard ratios, adjusted for potential baseline confounding variables (age, sex, disease duration, disease severity, and number of comorbidities). RESULTS: A total of 74 DBS-treated and 61 control patients with PD were included. For a median observational period of 14 years, patients treated with DBS were at lower risk of experiencing recurrent falls (hazard ratio = 0.57; 95% confidence interval, 0.37-0.90; P = 0.015) and psychosis (hazard ratio = 0.26; 95% confidence interval, 0.12-0.59; P = 0.001) compared with control patients. There was no significant difference in risk for dementia, institutionalization, or death. Disease progression as assessed by Hoehn and Yahr scores was not slower in DBS-treated patients. CONCLUSIONS: Treatment with chronic subthalamic DBS was associated with lower risk for recurrent falls and psychotic symptoms, effects that may be mediated through improved motor symptom control and reduction in dopaminergic therapies, respectively. There was no evidence for DBS effects on underlying disease progression.

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PURPOSE OF REVIEW: The molecular imaging field has been very instrumental in identifying the multiple network interactions that compose the human brain. The cerebral glucose metabolism is associated with neural function. 18F-fluoro-deoxyglucose-PET (FDG-PET) studies reflect brain metabolism in a pattern-specific manner. This article reviews FDG-PET studies in Parkinson's disease (PD), atypical parkinsonism (AP), Huntington's disease (HD), and dystonia. RECENT FINDINGS: The metabolic pattern of PD, disease progression, non-motor symptoms such as fatigue, depression, apathy, impulse control disorders, and cognitive impairment, and the risk of progression to dementia have been identified with FDG-PET studies. In prodromal PD, the REM sleep behavior disorder-related covariance pattern has been described. In AP, FDG-PET studies have demonstrated to be superior to D2/D3 SPECT in differentiating PD from AP. The metabolic patterns of HD and dystonia have also been described. FDG-PET studies are an excellent tool to identify patterns of brain metabolism.

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Bacillus cereus is a gram-positive, spore-forming bacterium possessing an important and historical record as a human-pathogenic bacterium. However, several strains of this species exhibit interesting potential to be used as plant growth-promoting rhizobacteria. Here, we report the draft genome sequence of B. cereus strain CITVM-11.1, which consists of 37 contig sequences, accounting for 5,746,486 bp (with a GC content of 34.8%) and 5,752 predicted protein-coding sequences. Several of them could potentially be involved in plant-bacterium interactions and may contribute to the strong antagonistic activity shown by this strain against the charcoal root rot fungus, Macrophomina phaseolina. This genomic sequence also showed a number of genes that may confer this strain resistance against several polluting heavy metals and for the bioconversion of mycotoxins.

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A new green on-line method for Boldine determination (BOL) in herbal drugs and phytopharmaceuticals, using its native fluorescence in acid media (λex=282nm; λem=373nm) has been developed. The presented methodology involves for the first time, a flow injection (FI) strategy using a mini-column of multiwalled carbon nanotubes as retention agent coupled with molecular fluorescence. Different parameters influence as sample pH and flow rate, eluent flow rate and composition; on BOL sensitivity and elution time was investigated by multifactorial techniques. Adequate dynamic calibration range (r2=0.9993) was obtained over a concentration interval of 0.029-27.0µgmL-1 BOL. The limits of detection (LOD) and quantification (LOQ) were 0.008 and 0.029µgmL-1, respectively. The average recoveries in explored samples ranged from 95% to 103%. Under optimized conditions, the throughput sample as high as 30h-1 was achieved with high repeatability performance (99%). The proposed development represents a useful and valuable tool emulating the analytical efficiency of the official methodologies for quality control of herbal and phytopharmaceutical drugs containing BOL. Moreover, this approach shows advantages respect to low cost, simplicity and environmental and analyst friendly.

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The use of chemical pesticides revolutionized agriculture with the introduction of DDT (Dichlorodiphenyltrichloroethane) as the first modern chemical insecticide. However, the effectiveness of DDT and other synthetic pesticides, together with their low cost and ease of use, have led to the generation of undesirable side effects, such as pollution of water and food sources, harm to non-target organisms and the generation of insect resistance. The alternative comes from biological control agents, which have taken an expanding share in the pesticide market over the last decades mainly promoted by the necessity to move towards more sustainable agriculture. Among such biological control agents, the bacterium Bacillus thuringiensis (Bt) and its insecticidal toxins have been the most studied and commercially used biological control agents over the last 40 years. However, some insect pests have acquired field-evolved resistance to the most commonly used Bt-based pesticides, threatening their efficacy, which necessitates the immediate search for novel strains and toxins exhibiting different modes of action and specificities in order to perpetuate the insecticidal potential of this bacterium.

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A simple, eco-friendly, sensitive and economic flow injection spectrofluorimetric method was developed for the determination of O-(ß-hydroxyethyl)rutosides. The procedure was based on the use of an anionic surfactant such as sodium dodecyl sulfate to provide an appreciable O-(ß-hydroxyethyl)rutosides fluorescence enhancement, increasing considerably the sensitivity of detection. All the variables affecting the fluorescence intensity were studied and optimized. The flow rate was 5 mL/min with detection at 450 nm (after excitation at 346 nm). A linear correlation between drug amount and peak area was established for O-(ß-hydroxyethyl)rutosides in the range of 0.01-200 µg/mL with a detection limit of 0.001 µg/mL (s/n=3). Validation processes were performed by recovering studies with satisfactory results. The new methodology can be employed for the routine analysis of O-(ß-hydroxyethyl)rutosides in bulks as well as in commercial formulations.

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BACKGROUND: The Unified Multiple System Atrophy Rating Scale (UMSARS) was developed to provide a surrogate measure of disease progression in multiple system atrophy. In the present study, the intrarater agreement of the motor examination part of the UMSARS was determined. METHODS: All patients were first examined face to face, while being video-recorded, by two senior and two junior investigators. The patients' videotaped examinations were reevaluated after 3 months. Intrarater reliability for each item was analyzed by kappa statistics. RESULTS: Overall weighted kappa (κ) values were at least substantial or excellent for all UMSARS motor examination items, except for ocular motor dysfunction, which showed only moderate intrarater agreement. Intrarater reliability was comparable between senior and junior raters, with all κ differences being ≤ 0.22. CONCLUSIONS: The motor examination part of the UMSARS was found to have satisfactory intrarater reliability in the present cohort.

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In the last decade we have witnessed substantial progress towards the understanding of Parkinson's disease. According to pathological and neuroimaging studies, the traditional view of Parkinson's disease that begins with the development of motor symptoms such as bradykinesia, rigidity and tremor, has begun to change. It is now understood that there would be a "premotor" or "preclinical" period in which the alphasynuclein pathology begins outside of the substantia nigra in the lower brainstem and autonomic nervous system. Although the pathophysiology of this phase is still unclear, it is currently thought that its symptoms would correspond to the so-called "non-motor symptoms". Hyposmia, depression, constipation and REM sleep disorders are one of the most relevant non-motor symptoms at this "premotor" stage. The spectrum of non-motor symptoms is very broad and covers the domains of neuropsychiatric, dysautonomic, gastrointestinal and sensory symptoms as well as sleep disorders. Neuropsychiatric symptoms such as depression, impulse control disorder, psychosis and dementia, are a major cause of disability as they are directly related to quality of life.

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A new spectrofluorimetric method for the determination of omeprazole (OMP) based on its degradation reaction catalyzed by ultraviolet (UV) light is proposed. OMP in aqueous solution is very unstable, which renders a serious difficulty for controlling its quality. It does not show native fluorescence, but when exposed to UV radiation, it generates a highly fluorescent degradation product with adequate stability for indirect OMP quantification. Under the studied optimal experimental conditions (pH, temperature, exposure time to UV radiation), a specific rate constant of 2.851 min⁻¹--described by zero-order kinetic--was obtained for the degradation reaction. Using λ(exc) 293 nm and λ(em) 317 nm, a linear relationship was obtained (r² 0.9998) in the concentration range of 0.1 to 1.3 µg mL⁻¹, with a detection limit of 1.07 10⁻³ µg mL⁻¹ (S/N = 3). The methodology developed was successfully applied to OMP quality control in pure drugs and tablet dosage forms without previous treatment, with good tolerance to common excipient, and a high level of concordance between the nominal and experimental values. This work constitutes an important contribution to knowledge of the degradation mechanism of OMP. It has been shown to be appropriate for OMP quality control, to have an adequate sampling rate, low cost instrument, and to be a less polluting procedure.

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The aim of this study was to develop a method for online spectrofluorimetric quality control of naphazoline (NPZ) in pharmaceuticals and raw drugs. A combination of a flow-injection analysis (FIA) system with micellar-enhanced fluorescence detection is presented as a powerful alternative for the rapid and sensitive analysis of naphazoline. Since NPZ shows low native fluorescence, the use of an anionic surfactant, such as sodium dodecyl sulphate (SDS), provides a considerable enhancement of fluorescence intensity and the nature of the technique allows a possible and easy adaptation to a FIA system. Using λ(exc) = 280 nm and λ(em) = 326 nm, a good linear relationship (LOL) was obtained in the range 0.003-10 µg mL(-1) with a detection limit (LOD) of 3 × 10(-4) µg mL(-1) (s/n = 3). Parameters related to the nature of the analytical signal and to the FIA manifold were optimized. Satisfactory recoveries were obtained in the analysis of commercial pharmaceutical formulations. The proposed method is simple, accurate and allows for high-speed sampling and considerably shorter analysis times. In addition, it requires inexpensive equipment and reagents and has easy operational conditions and no side effects, thus avoiding environmental pollution through toxic waste.

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A new, simple and highly sensitive method for spectrofluorimetric determination of amiloride (AMI) and furosemide (FUR) in pharmaceuticals is presented. The proposed method is based on the separation of AMI from FUR by solid-phase extraction using a nylon membrane, followed by spectrofluorimetric determination of both drugs, on the solid surface and the filtered aqueous solution, respectively. AMI shows low native fluorescence, but its separation-preconcentration by immobilization (solid-phase extraction) on nylon membrane surface provides a considerable enhancement in fluorescence intensity. The fluorescence determination is carried out at lambda(ex)=237, lambda(em)=415 nm for FUR; and lambda(ex)=365, lambda(em)=406 nm for AMI. The calibration graphs are linear in the range 3.20 x 10(-4) to 0.8 microg mL(-1) and 1.33 x 10(-3) to 4.0 microg mL(-1), for AMI and FUR, respectively, with a detection limit of 9.62 x 10(-5) and 4.01 x 10(-4) microg mL(-1) (S/N=3). The commonly found excipients in commercial pharmaceutical formulations do not interfere. The developed method is successfully applied to the determination of both drugs in pharmaceutical formulations.

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We aimed to investigate the prevalence of restless legs syndrome (RLS) according to essential diagnostic criteria, and to explore potential associations with clinical features, especially motor fluctuations, in a cohort of 113 patients with idiopathic Parkinson's disease (PD). Twenty-eight (24%) fulfilled essential diagnostic criteria for RLS. They were younger (63.1 +/- 8.6 vs. 68.8 +/- 9.0 years; P = 0.004), had an earlier onset of PD (54.1 +/- 9.5 vs. 59.2 +/- 10.3 years; P = 0.018), and received lower levodopa equivalent doses (578.4 +/- 382.2 vs. 779.1 +/- 459.6 mg/day; P = 0.04) than patients with PD who scored negative for RLS. In 23 patients (82%), RLS symptom onset was after PD onset (mean interval, 4.5 +/- 3.7 years). The majority (n = 17, 61%) who scored positive for RLS reported that the urge to move the legs and unpleasant sensations were associated with wearing off, raising the possibility of RLS mimics in fluctuating patients with PD.

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In REM sleep behavior disorder (RBD), several studies focused on electromyographic characterization of motor activity, whereas video analysis has remained more general. The aim of this study was to undertake a detailed and systematic video analysis. Nine polysomnographic records from 5 Parkinson patients with RBD were analyzed and compared with sex- and age-matched controls. Each motor event in the video during REM sleep was classified according to duration, type of movement, and topographical distribution. In RBD, a mean of 54 +/- 23.2 events/10 minutes of REM sleep (total 1392) were identified and visually analyzed. Seventy-five percent of all motor events lasted <2 seconds. Of these events, 1,155 (83.0%) were classified as elementary, 188 (13.5%) as complex behaviors, 50 (3.6%) as violent, and 146 (10.5%) as vocalizations. In the control group, 3.6 +/- 2.3 events/10 minutes (total 264) of predominantly elementary simple character (n = 240, 90.9%) were identified. Number and types of motor events differed significantly between patients and controls (P < 0.05). This study shows a very high number and great variety of motor events during REM sleep in symptomatic RBD. However, most motor events are minor, and violent episodes represent only a small fraction.

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Restrictive valvulopathy has been reported in association with dopamine agonist therapy in parkinsonian patients. The majority of reports have been related to pergolide, but anecdotal cases following treatment with bromocriptine or cabergoline have also been presented. It is presently unclear whether the potential induction of restrictive cardiac valvulopathy is a class effect of all dopamine agonists or if there is a differential risk between ergot and nonergot compounds. In this study, the frequency of a valvular regurgitation as assessed by routine transthoracic echocardiography was compared between 75 patients with Parkinson's disease (PD) treated with pergolide (n = 29), cabergoline (n = 13), pramipexole or ropinirole (n = 33), and 49 age-matched nonparkinsonian controls. The exposure to pergolide and cabergoline was associated with higher frequencies of valvular regurgitation grades 2 and 3 (31% and 47%) compared with age-matched controls (13%), while there was no increase of valvular regurgitation grades 2 and 3 in patients treated with nonergot compounds (10%). Evidence for restrictive valvulopathy was found in one patient treated with pergolide and cabergoline each. While this study shows similarly increased frequencies of valvular regurgitation in patients treated with the ergot agonists pergolide and cabergoline in comparison to both normal controls and patients treated with nonergot agonists, evidence for restrictive valvulopathy was only found in two cases. These results highlight the need for further prospective studies of the prevalence and underlying mechanisms of cardiac valvulopathy in PD patients treated with different dopamine agonists.

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