scholarly journals Progressively decreased nitrogen-stimulation of soil phosphatase activity with long-term nitrogen addition

2022 ◽  
Vol 169 ◽  
pp. 104213
Author(s):  
Ji Chen ◽  
Daryl L. Moorhead
Keyword(s):  
Phosphatase Activity ◽  
Nitrogen Addition ◽  
Soil Phosphatase ◽  
Stimulation Of

Deep brain stimulation of the posterior limb of the internal capsule in the treatment of central poststroke neuropathic pain of the lower limb: case series with long-term follow-up and literature review

2020 ◽  
Vol 133 (3) ◽  
pp. 830-838 ◽  
Author(s):  
Andrea Franzini ◽  
Giuseppe Messina ◽  
Vincenzo Levi ◽  
Antonio D’Ammando ◽  
Roberto Cordella ◽  
...  
Keyword(s):  
Neuropathic Pain ◽  
Lower Limb ◽  
Internal Capsule ◽  
Posterior Limb ◽  
Vas Score ◽  
The Mean ◽  
Deep Brain ◽  
Stimulation Of

OBJECTIVECentral poststroke neuropathic pain is a debilitating syndrome that is often resistant to medical therapies. Surgical measures include motor cortex stimulation and deep brain stimulation (DBS), which have been used to relieve pain. The aim of this study was to retrospectively assess the safety and long-term efficacy of DBS of the posterior limb of the internal capsule for relieving central poststroke neuropathic pain and associated spasticity affecting the lower limb.METHODSClinical and surgical data were retrospectively collected and analyzed in all patients who had undergone DBS of the posterior limb of the internal capsule to address central poststroke neuropathic pain refractory to conservative measures. In addition, long-term pain intensity and level of satisfaction gained from stimulation were assessed. Pain was evaluated using the visual analog scale (VAS). Information on gait improvement was obtained from medical records, neurological examination, and interview.RESULTSFour patients have undergone the procedure since 2001. No mortality or morbidity related to the surgery was recorded. In three patients, stimulation of the posterior limb of the internal capsule resulted in long-term pain relief; in a fourth patient, the procedure failed to produce any long-lasting positive effect. Two patients obtained a reduction in spasticity and improved motor capability. Before surgery, the mean VAS score was 9 (range 8–10). In the immediate postoperative period and within 1 week after the DBS system had been turned on, the mean VAS score was significantly lower at a mean of 3 (range 0–6). After a mean follow-up of 5.88 years, the mean VAS score was still reduced at 5.5 (range 3–8). The mean percentage of long-term pain reduction was 38.13%.CONCLUSIONSThis series suggests that stimulation of the posterior limb of the internal capsule is safe and effective in treating patients with chronic neuropathic pain affecting the lower limb. The procedure may be a more targeted treatment method than motor cortex stimulation or other neuromodulation techniques in the subset of patients whose pain and spasticity are referred to the lower limbs.

scholarly journals Pre-motor versus motor cerebral cortex neuromodulation for chronic neuropathic pain

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Igor Lavrov ◽  
Timur Latypov ◽  
Elvira Mukhametova ◽  
Brian Lundstrom ◽  
Paola Sandroni ◽  
...  
Keyword(s):  
Neuropathic Pain ◽  
Cerebral Cortex ◽  
Motor Cortex ◽  
Initial Assessment ◽  
Motor Cortex Stimulation ◽  
Chronic Neuropathic Pain ◽  
Long Term Effect ◽  
Stimulation Of

AbstractElectrical stimulation of the cerebral cortex (ESCC) has been used to treat intractable neuropathic pain for nearly two decades, however, no standardized approach for this technique has been developed. In order to optimize targeting and validate the effect of ESCC before placing the permanent grid, we introduced initial assessment with trial stimulation, using a temporary grid of subdural electrodes. In this retrospective study we evaluate the role of electrode location on cerebral cortex in control of neuropathic pain and the role of trial stimulation in target-optimization for ESCC. Location of the temporary grid electrodes and location of permanent electrodes were evaluated in correlation with the long-term efficacy of ESCC. The results of this study demonstrate that the long-term effect of subdural pre-motor cortex stimulation is at least the same or higher compare to effect of subdural motor or combined pre-motor and motor cortex stimulation. These results also demonstrate that the initial trial stimulation helps to optimize permanent electrode positions in relation to the optimal functional target that is critical in cases when brain shift is expected. Proposed methodology and novel results open a new direction for development of neuromodulation techniques to control chronic neuropathic pain.

Electrical stimulation of referred sensation area alleviates phantom limb pain

2021 ◽  
pp. 1-10
Author(s):  
Michihiro Osumi ◽  
Daisuke Shimizu ◽  
Yuki Nishi ◽  
Shu Morioka
Keyword(s):  
Electrical Stimulation ◽  
Single Case ◽  
Phantom Limb Pain ◽  
Phantom Limb ◽  
Long Term Effects ◽  
Limb Pain ◽  
Short Term ◽  
Analgesic Effects ◽  
Stimulation Of

Background: Patients with brachial plexus avulsion (BPA) usually experience phantom sensations and phantom limb pain (PLP) in the deafferented limb. It has been suggested that evoking the sensation of touch in the deafferented limb by stimulating referred sensation areas (RSAs) on the cheek or shoulder might alleviate PLP. However, feasible rehabilitation techniques using this approach have not been reported. Objective: The present study sought to examine the analgesic effects of simple electrical stimulation of RSAs in BPA patients with PLP. Methods: Study 1: Electrical stimulation of RSAs for 60 minutes was conducted for six BPA patients suffering from PLP to examine short-term analgesic effects. Study 2: A single case design experiment was conducted with two BPA patients to investigate whether electrical stimulation of RSAs was more effective for alleviating PLP than control electrical stimulation (electrical stimulation of sites on side opposite to the RSAs), and to elucidate the long-term effects of electrical stimulation of RSAs. Results: Study 1: Electrical stimulation of RSAs evoked phantom touch sensations in the deafferented limb, and significantly alleviated PLP (p <  0.05). Study 2: PLP was alleviated more after electrical stimulation on RSAs compared with control electrical stimulation (p <  0.05). However, the analgesic effects of electrical stimulation on RSAs were observed only in the short term, not in the long term (p >  0.05). Conclusions: Electrical stimulation of RSAs not only evoked phantom touch sensation but also alleviated PLP in the short term. The results indicate that electrical stimulation of RSAs may provide a useful practical rehabilitation technique for PLP. Future studies will be required to clarify the mechanisms underlying immediate PLP alleviation via electrical stimulation of RSAs.

scholarly journals Biofilm Lithography enables high-resolution cell patterning via optogenetic adhesin expression

2018 ◽  
Vol 115 (14) ◽  
pp. 3698-3703 ◽  
Author(s):  
Xiaofan Jin ◽  
Ingmar H. Riedel-Kruse
Keyword(s):  
Escherichia Coli ◽  
Cell Patterning ◽  
Biophysical Model ◽  
Microbial Consortia ◽  
Bacterial Biofilms ◽  
Surface Pretreatment ◽  
Resolution Cell ◽  
Stimulation Of

Bacterial biofilms represent a promising opportunity for engineering of microbial communities. However, our ability to control spatial structure in biofilms remains limited. Here we engineerEscherichia coliwith a light-activated transcriptional promoter (pDawn) to optically regulate expression of an adhesin gene (Ag43). When illuminated with patterned blue light, long-term viable biofilms with spatial resolution down to 25 μm can be formed on a variety of substrates and inside enclosed culture chambers without the need for surface pretreatment. A biophysical model suggests that the patterning mechanism involves stimulation of transiently surface-adsorbed cells, lending evidence to a previously proposed role of adhesin expression during natural biofilm maturation. Overall, this tool—termed “Biofilm Lithography”—has distinct advantages over existing cell-depositing/patterning methods and provides the ability to grow structured biofilms, with applications toward an improved understanding of natural biofilm communities, as well as the engineering of living biomaterials and bottom–up approaches to microbial consortia design.

scholarly journals Lipoxygenase Inhibition by Plant Extracts

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 152
Author(s):  
Melita Lončarić ◽  
Ivica Strelec ◽  
Tihomir Moslavac ◽  
Drago Šubarić ◽  
Valentina Pavić ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Unsaturated Fatty Acids ◽  
Inflammatory Reactions ◽  
Long Term Storage ◽  
Food Properties ◽  
Lipoxygenase Inhibition ◽  
Plant Families ◽  
Term Storage ◽  
Stimulation Of

Lipoxygenases are widespread enzymes that catalyze oxidation of polyunsaturated fatty acids (linoleic, linolenic, and arachidonic acid) to produce hydroperoxides. Lipoxygenase reactions can be desirable, but also lipoxygenases can react in undesirable ways. Most of the products of lipoxygenase reactions are aromatic compounds that can affect food properties, especially during long-term storage. Lipoxygenase action on unsaturated fatty acids could result in off-flavor/off-odor development, causing food spoilage. In addition, lipoxygenases are present in the human body and play an important role in stimulation of inflammatory reactions. Inflammation is linked to many diseases, such as cancer, stroke, and cardiovascular and neurodegenerative diseases. This review summarized recent research on plant families and species that can inhibit lipoxygenase activity.

Induction of long-term potentiation without participation of N-methyl-D-aspartate receptors in kitten visual cortex

1991 ◽  
Vol 65 (1) ◽  
pp. 20-32 ◽  
Author(s):  
Y. Komatsu ◽  
S. Nakajima ◽  
K. Toyama
Keyword(s):  
Nmda Receptors ◽  
Stimulus Frequency ◽  
Low Frequency ◽  
Nmda Antagonist ◽  
Long Term Potentiation ◽  
Conditioning Stimulation ◽  
Postsynaptic Potential ◽  
Term Potentiation ◽  
Stimulation Of

1. Intracellular recording was made from layer II-III cells in slice preparations of kitten (30-40 days old) visual cortex. Low-frequency (0.1 Hz) stimulation of white matter (WM) usually evoked an excitatory postsynaptic potential (EPSP) followed by an inhibitory postsynaptic potential (IPSP). The postsynaptic potentials (PSPs) showed strong dependence on stimulus frequency. Early component of EPSP and IPSP evoked by weak stimulation both decreased monotonically at frequencies greater than 0.5-1 Hz. Strong stimulation similarly depressed the early EPSP at higher frequencies (greater than 2 Hz) and replaced the IPSP with a late EPSP, which had a maximum amplitude in the stimulus frequency range of 2-5 Hz. 2. Very weak WM stimulation sometimes evoked EPSPs in isolation from IPSPs. The falling phase of the EPSP revealed voltage dependence characteristic to the responses mediated by N-methyl-D-aspartate (NMDA) receptors and was depressed by application of an NMDA antagonist DL-2-amino-5-phosphonovalerate (APV), whereas the rising phase of the EPSP was insensitive to APV. 3. The early EPSPs followed by IPSPs were insensitive to APV but were replaced with a slow depolarizing potential by application of a non-NMDA antagonist 6,7-dinitro-quinoxaline-2,3-dione (DNQX), indicating that the early EPSP is mediated by non-NMDA receptors. The slow depolarization was mediated by NMDA receptors because it was depressed by membrane hyperpolarization or addition of APV. 4. The late EPSP evoked by higher-frequency stimulation was abolished by APV, indicating that it is mediated by NMDA receptors, which are located either on the recorded cell or on presynaptic cells to the recorded cells. 5. Long-term potentiation (LTP) of EPSPs was examined in cells perfused with solutions containing 1 microM bicuculline methiodide (BIM), a gamma-aminobutyric acid (GABA) antagonist. WM was stimulated at 2 Hz for 15 min as a conditioning stimulus to induce LTP, and the resultant changes were tested by low-frequency (0.1 Hz) stimulation of WM. 6. LTP of early EPSPs occurred in more than one-half of the cells (8/13) after strong conditioning stimulation. The rising slope of the EPSP was increased 1.6 times on average. 7. To test involvement of NMDA receptors in the induction of LTP in the early EPSP, the effect of conditioning stimulation was studied in a solution containing 100 microM APV, which was sufficient to block completely synaptic transmission mediated by NMDA receptors. LTP occurred in the same frequency and magnitude as in control solution.

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