Recognizing the risks of brain stimulation

Noort, Maurits van den,Lim, Sabina,Bosch, Peggy American Association for the Advancement of Scienc 2014 Science Vol.346 No.6215

Bilateral Scapulohumeral Ankylosis after Prolonged Mechanical Ventilation

Manon L. van Lotten,J. Rieneke Schreinemakers,Arthur van Noort,Maarten V. Rademakers 대한정형외과학회 2016 Clinics in Orthopedic Surgery Vol.8 No.3

This case demonstrates a rarely reported bilateral scapulohumeral bony ankylosis. A young woman developed extensive heterotopic ossifications (HOs) in both shoulder joints after being mechanically ventilated for several months at the intensive care unit in a comatose status. She presented with a severe movement restriction of both shoulder joints. Surgical resection of the bony bridges was performed in 2 separate sessions with a significant improvement of shoulder function afterwards. No postoperative complications, pain, or recurrence of HOs were noted at 1-year follow-up. Mechanical ventilation, immobilization, neuromuscular blockage, and prolonged sedation are known risk factors for the development of HOs in the shoulder joints. Relatively early surgical resection of the HOs can be performed safely in contrary to earlier belief. Afterwards, nonsteroidal anti-inflammatory drugs and/or radiation therapy can be possible treatment modalities to prevent recurrence of HOs.

Ipsilateral Putamen and Insula Activation by Both Left and Right GB34 Acupuncture Stimulation: An fMRI Study on Healthy Participants

Yeo, Sujung,van den Noort, Maurits,Bosch, Peggy,Lim, Sabina Hindawi Publishing Corporation 2016 Evidence-based Complementary and Alternative Medic Vol.2016 No.-

<P>The modulatory effects on the brain during right versus left side acupuncture stimulation of the same acupuncture point have been a subject of controversy. For clarification of this important methodological issue, the present study was designed to compare the blood oxygen level-dependent responses of acupuncture stimulation on the right versus left<I> Yanglingquan</I> (GB34). Twenty-two healthy subjects received right or left GB34 acupuncture. Our results show that acupuncture on the left GB34 induced neural responses in the left putamen, caudate body, insula, postcentral gyrus, claustrum, right and left thalamus, right middle frontal gyrus, hypothalamus, and subthalamic nucleus. Acupuncture on the right GB34 induced neural responses in the right middle frontal gyrus, inferior parietal lobule, thalamus, putamen, lateral globus pallidus, medial globus pallidus, and insula. Interestingly, the putamen and insula were ipsilaterally activated by acupuncture on either the left or right GB34; therefore, they seem to be the main target areas affected by GB34 acupuncture. This is the first reported functional magnetic resonance imaging study directly comparing needling on the right and left GB34. Although more replication studies are needed, our preliminary results prove that acupuncture has different modulatory effects on the brain when performed on the right versus left side.</P>

Use of a Microvalve-controlled Microfluidic Device in a Chemotaxis Assay of Tetrahymena pyriformis in Response to Amino Acids Released from Bacteria

남성원,Danny van Noort,양윤선,김소현,박성수 한국바이오칩학회 2007 BioChip Journal Vol.1 No.2

In this study, we introduce a microfluidic device equipped with pneumatically-actuated valves, generating a linear gradient of chemoeffectors to quantify the chemotactic response of Tetrahymena pyriformis, a freshwater ciliate to amino acids excreted from bacteria. The microfluidic device was fabricated from an elastomer, polydimethylsiloxane (PDMS), using multi-layer soft lithography. The components of the device include electronically-controlled pneumatic microvalves, microchannels and microchambers. The linear gradient of the chemoeffectors was established by releasing a chemical from a ciliatefree microchamber into a microchamber containing the ciliate. The ciliate showed chemotactic behaviours by either swimming toward or avoiding the gradient. By counting the number of ciliate residing in each microchamber, we obtained a precise timeresponse curve. The ciliate in the microfluidic device were sensitive enough to be attracted to 0.1 femtomolar aspartate, suggesting that ciliates as a predator can track down food patches composed of a few bacterial cells. With the use of receptor inhibitors, such as tetraethyl ammonium (TEA) or the grape polyphenol resveratol, we have also demonstrated that the calcium signalling plays an important role in motility and following chemotactic behaviours.

A study of the effects of 8-week acupuncture treatment on patients with Parkinson's disease

Yeo, Sujung,van den Noort, Maurits,Bosch, Peggy,Lim, Sabina Williams & Wilkins Co 2018 Medicine Vol.97 No.50

<▼1><P>Supplemental Digital Content is available in the text</P></▼1><▼2><P><B>Abstract</B></P><P><B>Background:</B></P><P>Parkinson's disease (PD) is a degenerative brain disorder, resulting in decreased neural responses in the supplementary motor area, putamen, and thalamus. Previous research showed that acupuncture was able to improve the motor dysfunction. The primary aim of this study is to assess the efficacy of longer acupuncture treatment for preventing brain degeneration in patients with PD.</P><P><B>Methods:</B></P><P>Ten outpatients with PD were recruited from Kyung Hee Medical Hospital. Behavioral and neural responses were examined before and after 8 weeks of acupuncture treatment. A semi-individualized treatment approach was used; patients were treated for 15 minutes with 120-Hz electro-acupuncture at the right GB34 and Taechung (LR3), followed by manual acupuncture based on the individual symptoms of the patient.</P><P><B>Results:</B></P><P>Immediately after 8 weeks of acupuncture treatment, the Unified Parkinson's Disease Rating Scale (UPDRS) sub-scores and the depression scores for the patients had statistically decreased compared to the scores before acupuncture treatment; moreover, 8 weeks later, these scores remained stable. Compared to the neural responses before the acupuncture stimulation, those after the acupuncture treatment were significantly higher in the thalamus, cingulate gyrus, anterior cingulate, lingual gyrus, parahippocampal gyrus, lateral globus pallidus, mammillary body, middle temporal gyrus, cuneus, and fusiform gyrus. Finally, a positive correlation was found between the UPDRS and the mean magnetic resonance signal change for the thalamus.</P><P><B>Conclusion:</B></P><P>This study found beneficial clinical effects of 8-week acupuncture treatment in the brains of patients with PD.</P></▼2>

The Fascinating Interplay between Growth Hormone, Insulin-Like Growth Factor-1, and Insulin

Aart J. van der Lely,Eline C. Nijenhuis-Noort,Kirsten A. Berk,Sebastian J. C. M. M. Neggers 대한내분비학회 2024 Endocrinology and metabolism Vol.39 No.1

This review intends to provide the reader with a practical overview of several (patho)physiological conditions in which knowledge of the interplay between growth hormone (GH), insulin-like growth factor-1 (IGF-1), and insulin is important. This might help treating physicians in making the right decisions on how to intervene and improve metabolism for the benefit of patients, and to understand why and how metabolism responds in their specific cases. We will specifically address the interplay between GH, IGF-1, and insulin in type 1 and 2 diabetes mellitus, liver cirrhosis, and acromegaly as examples in which this knowledge is truly necessary.

A Microbore Tubing Based Spiral for Multistep Cell Fractionation

Pasitka, Laura,van Noort, Danny,Lim, Wanyoung,Park, Sungsu,Mandenius, Carl-Fredrik American Chemical Society 2018 ANALYTICAL CHEMISTRY - Vol.90 No.21

<P>Cells were separated with the aid of a multistep spiral fractionation device, utilizing hydrodynamic forces in a spiral tubing. The spiral was fabricated using “off-the-shelf” microbore tubing, allowing for cheap and fast prototyping to achieve optimal cell separation. As a first step, a model system with 20 and 40 μm beads was used to demonstrate the effectiveness of the multistep separation device. With an initial purity of 5%, a separation purity of 83% was achieved after a two-step separation with the addition of 0.1% polyethylene glycol (PEG)-8000. Next, doxorubicin-resistant polyploid giant breast cancer cells (MDA-MB-231) were separated from doxorubicin-sensitive monoploid small breast cancer cells in the same fashion as the beads, resulting in a purity of around 40%, while maintaining a cell viability of more than 90%. Combined with basic cell analytical methods, the hydrodynamic separation principle of the device could be envisaged to be useful for a variety of cell fractionation needs in cell biology and in clinical applications.</P> [FIG OMISSION]</BR>

Effective mixing in a microfluidic chip using magnetic particles

Lee, Seung Hwan,van Noort, Danny,Lee, Ji Youn,Zhang, Byoung-Tak,Park, Tai Hyun Royal Society of Chemistry 2009 Lab on a chip Vol.9 No.3

<P>We present a novel active mixing method in a microfluidic chip, where the controlled stirring of magnetic particles is used to achieve an effective mixing of fluids. To perform mixing, the ferromagnetic particles were embedded and manipulated under the influence of a rotating magnetic field. By aligning the magnetic beads along the magnetic field lines, rod-like structures are formed, functioning as small stir bars. Under higher flow conditions the particles did not form the typical rod structure but rather formed aggregates, which were even more beneficial for mixing. Our system reached a 96% mixing efficiency in a relatively short distance (800 µm) at a flow rate of 1.2–4.8 mm/s. These results demonstrate that our mixing method is useful for microfluidic devices with low aspect ratios and molecules with large molecular weights.</P> <P>Graphic Abstract</P><P>We present the design and fabrication of a novel mixing device, where the controlled stirring of magnetic particles is used to achieve an effective mixing in a microfluidic chip. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b814371d'> </P>

Biomolecular theorem proving on a chip: a novel microfluidic solution to a classical logic problem.

Lee, Seung Hwan,van Noort, Danny,Yang, Kyung-Ae,Lee, In-Hee,Zhang, Byoung-Tak,Park, Tai Hyun Royal Society of Chemistry 2012 Lab on a chip Vol.12 No.10

<P>Biomolecules inside a microfluidic system can be used to solve computational problems, such as theorem proving, which is an important class of logical reasoning problems. In this article, the Boolean variables (literals) were represented using single-stranded DNA molecules, and theorem proving was performed by the hybridization and ligation of these variables into a double-stranded 'solution' DNA. Then, a novel sequential reaction mixing method in a microfluidic chip was designed to solve a theorem proving problem, where a reaction loop and three additional chambers were integrated and controlled by pneumatic valves. DNA hybridization, ligation, toehold-mediated DNA strand displacement, exonuclease I digestion, and fluorescence detection of the double-stranded DNA were sequentially performed using this platform. Depending on the computational result, detection of the correct answer was demonstrated based on the presence of a fluorescence signal. This result is the first demonstration that microfluidics can be used to facilitate DNA-based logical inference.</P>

A biological sensor platform using a pneumatic-valve controlled microfluidic device containing <i>Tetrahymena pyriformis</i>

Nam, Seong-Won,Noort, Danny Van,Yang, Yoonsun,Park, Sungsu Royal Society of Chemistry 2007 Lab on a chip Vol.7 No.5

<P>In this study, we introduce a microfluidic device equipped with pneumatically actuated valves, generating a linear gradient of chemoeffectors to quantify the chemotactic response of <I>Tetrahymena pyriformis</I>, a freshwater ciliate. The microfluidic device was fabricated from an elastomer, poly(dimethylsiloxane) (PDMS), using multi-layer soft lithography. The components of the device include electronically controlled pneumatic microvalves, microchannels and microchambers. The linear gradient of the chemoeffectors was established by releasing a chemical from a ciliate-free microchamber into a microchamber containing the ciliate. The ciliate showed chemotactic behaviours by either swimming toward or avoiding the gradient. By counting the number of ciliates residing in each microchamber, we obtained a precise time–response curve. The ciliates in the microfluidic device were sensitive enough to be attracted to 10 pmol glycine-proline, which indicates a 10<SUP>5</SUP> increase in the ciliate's known sensitivity. With the use of blockers, such as <SMALL>DL</SMALL>-2-amino-5-phosphonopentanoic acid (APPA) or lanthanum chloride (LaCl<SUB>3</SUB>), we have demonstrated that the NMDA (<I>N</I>-methyl-<SMALL>D</SMALL>-aspartate) receptor plays a critical role in the perception of chemoeffectors, whereas the Ca<SUP>2+</SUP> channel is related to the motility of the ciliate. These results demonstrate that our microfluidic chemotaxis assay system is useful not only for the study of ciliate chemotaxis but also for a better understanding of the signal transduction mechanism on their receptors.</P> <P>Graphic Abstract</P><P>Ciliates in the left chamber chemotactically moved to the right chamber containing 10 pM glycine-proline within 10 min after the connecting microvalve between the two chambers was opened. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b617357h'> </P>