scholarly journals Rapidly characterizing the fast dynamics of RNA genetic circuitry with cell-free transcription-translation (TX-TL) systems

2014 ◽  
Author(s):  
Melissa K Takahashi ◽  
James Chappell ◽  
Clarmyra A Hayes ◽  
Zachary Z Sun ◽  
Vipul Singhal ◽  
...  
Keyword(s):  
Response Time ◽  
Test Cycle ◽  
Threshold Response ◽  
Degradation Rates ◽  
Slow Design ◽  
Design Build ◽  
Input Module ◽  
Single Input ◽  
A Current

RNA regulators are emerging as powerful tools to engineer synthetic genetic networks or rewire existing ones. A potential strength of RNA networks is that they may be able to propagate signals on timescales that are set by the fast degradation rates of RNAs. However, a current bottleneck to verifying this potential is the slow design-build-test cycle of evaluating these networks in vivo. Here we adapt anEscherichia coli-based cell- free transcription-translation (TX-TL) system for rapidly prototyping RNA networks. We used this system to measure the response time of an RNA transcription cascade to be approximately five minutes per step of the cascade. We also show that this response time can be adjusted with temperature and regulator threshold response tuning. Finally we use TX-TL to prototype a new RNA network, an RNA single input module, and show that this network temporally stages the expression of two genesin vivo. Now published as: ACS Synthetic Biology doi:10.1021/sb400206c

scholarly journals Role of Bradykinin Type 2 Receptors in Human Sweat Secretion: Translational Evidence Does Not Support a Functional Relationship

2021 ◽  
Vol 34 (3) ◽  
pp. 162-166
Author(s):  
Thad E. Wilson ◽  
Seetharam Narra ◽  
Kristen Metzler-Wilson ◽  
Artur Schneider ◽  
Kelsey A. Bullens ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Sweat Rate ◽  
Sweat Glands ◽  
Potential Therapeutic Target ◽  
Sweat Secretion ◽  
Hoe 140 ◽  
A Current

Bradykinin increases skin blood flow via a cGMP mechanism but its role in sweating in vivo is unclear. There is a current need to translate cell culture and nonhuman paw pad studies into in vivo human preparations to test for therapeutic viability for disorders affecting sweat glands. Protocol 1: physiological sweating was induced in 10 healthy subjects via perfusing warm (46–48°C) water through a tube-lined suit while bradykinin type 2 receptor (B2R) antagonist (HOE-140; 40 μM) and only the vehicle (lactated Ringer’s) were perfused intradermally via microdialysis. Heat stress increased sweat rate (HOE-140 = +0.79 ± 0.12 and vehicle = +0.64 ± 0.10 mg/cm<sup>2</sup>/min), but no differences were noted with B2R antagonism. Protocol 2: pharmacological sweating was induced in 6 healthy subjects via intradermally perfusing pilocarpine (1.67 mg/mL) followed by the same B2R antagonist approach. Pilocarpine increased sweating (HOE-140 = +0.38 ± 0.16 and vehicle = +0.32 ± 0.12 mg/cm<sup>2</sup>/min); again no differences were observed with B2R antagonism. Last, 5 additional subjects were recruited for various control experiments which identified that a functional dose of HOE-140 was utilized and it was not sudorific during normothermic conditions. These data indicate B2R antagonists do not modulate physiologically or pharmacologically induced eccrine secretion volumes. Thus, B2R agonist/antagonist development as a potential therapeutic target for hypo- and hyperhidrosis appears unwarranted.

scholarly journals Relationship between Degradation Rates of Proteins in Vivo and Their Susceptibility to Lysosomal Proteases

1974 ◽  
Vol 249 (19) ◽  
pp. 6364-6365
Author(s):  
Harold I. Segal ◽  
James R. Winkler ◽  
Mary P. Miyagi
Keyword(s):  
Degradation Rates ◽  
Lysosomal Proteases

scholarly journals Synthesis and degradation rates of collagens in vivo in whole skin of rats, studied with 18O2 labelling

1986 ◽  
Vol 240 (2) ◽  
pp. 431-435 ◽  
Author(s):  
J A Molnar ◽  
N Alpert ◽  
J F Burke ◽  
V R Young
Keyword(s):  
Gas Chromatography Mass Spectrometry ◽  
Collagen Turnover ◽  
Growing Rats ◽  
Soluble Collagen ◽  
Insoluble Collagen ◽  
Degradation Rates ◽  
Labelling Procedure ◽  
Skin Biopsies ◽  
Synthesis And Degradation

Rats of synthesis and degradation in vivo of collagens in 0.5 M-acetic acid-soluble and -insoluble extracts from skins of three growing rats were determined by using a labelling procedure involving exposure of the animals to an atmosphere of 18O2 for 36 h. For comparison, rats also received injections of [2H]proline. Serial skin biopsies were taken at frequent intervals over 392 days. Enrichment of 18O and 2H in the hydroxyproline of the collagen fractions was determined by gas chromatography-mass spectrometry. Changes in size of the soluble and insoluble collagen pools were considered in the evaluation of isotope kinetic data. The insoluble collagen fraction showed no degradation. The efflux (mean +/- S.D., expressed as mumol of hydroxyproline) from the soluble collagen pool was estimated to be 59.9 +/- 1.9 per day from the 18O data, and 25.5 +/- 7.5 per day from the 2H results. The finding indicates significant reutilization of 2H-radiolabelled proline for hydroxyproline synthesis. From these isotope data and estimates of size of the collagen pools it was determined that 55% of the collagen disappearing from the soluble pool was due to maturation into insoluble collagens and 45% of the disappearance was a result of actual degradation of soluble collagen. These results confirm the utility of 18O2 as a non-reutilizable label for studies of collagen turnover in vivo.

scholarly journals Polarization sensitive optical coherence tomography with single input for imaging depth-resolved collagen organizations

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Peijun Tang ◽  
Mitchell A. Kirby ◽  
Nhan Le ◽  
Yuandong Li ◽  
Nicole Zeinstra ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Structural Integrity ◽  
Ex Vivo ◽  
Polarization State ◽  
Transmission Model ◽  
Optical Coherence ◽  
Healthy Human ◽  
Collagen Organization ◽  
Single Input

AbstractCollagen organization plays an important role in maintaining structural integrity and determining tissue function. Polarization-sensitive optical coherence tomography (PSOCT) is a promising noninvasive three-dimensional imaging tool for mapping collagen organization in vivo. While PSOCT systems with multiple polarization inputs have demonstrated the ability to visualize depth-resolved collagen organization, systems, which use a single input polarization state have not yet demonstrated sufficient reconstruction quality. Herein we describe a PSOCT based polarization state transmission model that reveals the depth-dependent polarization state evolution of light backscattered within a birefringent sample. Based on this model, we propose a polarization state tracing method that relies on a discrete differential geometric analysis of the evolution of the polarization state in depth along the Poincare sphere for depth-resolved birefringent imaging using only one single input polarization state. We demonstrate the ability of this method to visualize depth-resolved myocardial architecture in both healthy and infarcted rodent hearts (ex vivo) and collagen structures responsible for skin tension lines at various anatomical locations on the face of a healthy human volunteer (in vivo).

In Vivo vs. In Vitro Response Time of Trancutaneous Po2Electrodes A comparison of four devices in newborn infants

1978 ◽  
Vol 22 ◽  
pp. 40-48 ◽  
Author(s):  
H. T. Versmold ◽  
O. Linderkamp ◽  
K. H. Stuffer ◽  
M. Holzmann ◽  
K. P. Riegel
Keyword(s):  
Response Time ◽  
Newborn Infants ◽  
In Vitro Response

Persian clover and maize silage. III. Rumen fermentation and balance of nutrients when clover and silage are fed to lactating dairy cows

1994 ◽  
Vol 45 (8) ◽  
pp. 1783 ◽  
Author(s):  
CR Stockdale
Keyword(s):  
Zea Mays ◽  
Dairy Cows ◽  
Milk Fat ◽  
Maize Silage ◽  
Lactating Dairy Cows ◽  
Degradation Rates ◽  
Persian Clover ◽  
Yield Responses ◽  
Trifolium Resupinatum

Six rumen fistulated dairy cows, at various stages of lactation, were housed in metabolism stalls on a total of nine occasions in three experiments in which various combinations of Persian clover (Trifolium resupinatum) and maize (Zea mays) silage were offered. These experiments considered some aspects of digestion of Persian clover and Persian clover/maize silage diets in order to understand the good milk yield responses attributed to maize silage measured in previous research. Rumen ammonia concentrations and nylon bag degradation rates suggested that the cows made better use of one or both feeds when Persian clover and maize silage were offered together than they did when Persian clover was offered alone. While Persian clover and maize silage appeared to be a substantially inferior diet in terms of apparent in vivo digestibility coefficients and availability of nutrients when compared with Persian clover offered alone, milk yields were unaffected. In addition, no matter how much maize silage was offered, milk fat content remained constant. These results were attributed to an improved balance of absorbed nutrients.

Parotid Gland Function in Streptozotocin-diabetic Rats

1987 ◽  
Vol 66 (2) ◽  
pp. 425-429 ◽  
Author(s):  
L.C. Anderson
Keyword(s):  
Protein Composition ◽  
Diabetic Rats ◽  
Response Threshold ◽  
Maximal Response ◽  
Parotid Glands ◽  
Threshold Response ◽  
Parotid Acinar Cells ◽  
Streptozotocin Diabetic Rats ◽  
Gland Function

The in vivo response of parotid glands to adrenergic, cholinergic, and peptidergic agonists was studied in control, streptozotocin- (one month's duration), and insulin-treated (three hr) diabetic rats. Neither diabetes nor insulin had an effect on the response to physalaemin. In contrast, physalaemin threshold-dose was lower and maximal response greater in control rats placed on a bulk diet. As previously described, diabetes resulted in nonparallel changes in parotid protein composition, including a reduction in amylase and an increase in peroxidase concentrations (mg/mg protein). In contrast to the results observed with physalaemin, response to methacholine was significantly reduced in diabetic animals, and could be restored to control levels by insulin. Placement of animals on a bulk-diet, however, had no effect on threshold response to methacholine. Finally, response threshold for epinephrine was unaffected by diabetes, insulin, or bulk diet. Thus, insulin appears, directly and specifically, to alter the response of parotid acinar cells to cholinergic stimulation.

scholarly journals Microstructure and Mechanical Properties of PU/PLDL Sponges Intended for Grafting Injured Spinal Cord

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2693
Author(s):  
Anna Lis-Bartos ◽  
Dariusz Szarek ◽  
Małgorzata Krok-Borkowicz ◽  
Krzysztof Marycz ◽  
Włodzimierz Jarmundowicz ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Spinal Cord ◽  
Young Modulus ◽  
In Vivo Studies ◽  
Polymer Composition ◽  
In Vitro Toxicity ◽  
Injured Spinal Cord ◽  
Degradation Rates

Highly porous, elastic, and degradable polyurethane and polyurethane/polylactide (PU/PLDL) sponges, in various shapes and sizes, with open interconnected pores, and porosity up to 90% have been manufactured. They have been intended for gap filling in the injured spinal cord. The porosity of the sponges depended on the content of polylactide, i.e., it decreased with the increase of polylactide content. The rise of polylactide content caused an increase of Young modulus and rigidity as well as a more complex morphology of the polyurethane/polylactide blends. The mechanical properties, in vitro toxicity, and degradation in artificial cerebrospinal fluid were tested. Sponges underwent continuous degradation with varying degradation rates depending on the polymer composition. In vitro cell studies with fibroblast cultures proved the biocompatibility of the polymers. Based on the obtained results, the designed PU/PLDL sponges appeared to be promising candidates for bridging gaps within injured spinal cord in further in vitro and in vivo studies.

Single-Input Module Motif, SIM

2013 ◽  
pp. 1954-1954
Keyword(s):  
Input Module ◽  
Single Input

Natural Poly(Hydroxybutyrate-Hydroxyvalerate) Polymers as Degradable Biomatertals.

1995 ◽  
Vol 394 ◽  
Author(s):  
Cyril Chaput ◽  
L'Hocine Yahia ◽  
Amine Selmani ◽  
Charles-Hilaire Rivard
Keyword(s):  
Copolymer Composition ◽  
Inflammatory Reactions ◽  
Accelerated Degradation ◽  
Physico Chemical ◽  
Degradation Rates ◽  
Degradable Biomaterials ◽  
Tissue Reactions ◽  
Toxic Responses

AbstractPoly(ß-hydroxybutyrate-co-13-hydroxyvalerate) have been recently proposed as degradable biomaterials for drug delivery systems, sutures, bone plates and short-term implants. Three P-B\HV (7, 14 & 22 % HV) films were analyzed for in vitro cytotoxicity and aqueous accelerated degradation, in vivo degradation and tissue reactions. The PHB/HV materials and extracts elicit few or mild toxic responses, do not lead in vivo to tissue necrosis or abscess formation, but provoke acute inflammatory reactions slightly decreasing with the time. The degradation of PHB/HV polymers present low rates in vitro as well as in vivo. The weight loss rate generally increases with the copolymer composition (HV content) and ranges from 0.15- 0.30 (in vitro) to 0.25 %/day (in vivo). Compositional and physico-chemical changes in PHB/HV materials were rapidly detected during the accelerated hydrolysis, but were much slower to appear in vivo. The structural and mechanical integrity of PHB/HV materials tend to disappear early in vitro as well as in vivo. After 90 wks in dorsal muscular tissues of adult sheep, there was no significant dissolution of the PHB/HV polymer, 50–60% of the initial weight still remaining. PHB/HV polymers are biodegradable materials, either by hydrolysis or implantation, but with extremely low dissolution or degradation rates.

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