Cellular and synaptic properties of amygdala-kindled pyriform cortex in vitro

1986 ◽  
Vol 55 (6) ◽  
pp. 1295-1307 ◽  
Author(s):  
D. C. McIntyre ◽  
R. K. Wong
Keyword(s):  
Electrical Stimulation ◽  
Beta Agonist ◽  
Excitatory Effect ◽  
Pyriform Cortex ◽  
Long Latency ◽  
The Mean ◽  
And Control ◽  
Facilitatory Action ◽  
Pyriform Cells

The evoked and spontaneous activity of neurons in the pyriform cortex of control and kindled rats was examined using a coronal slice preparation containing the amygdala-pyriform region. Electrical stimulation of the amygdala nuclei elicited synchronized burst responses in pyriform cells of slices from both control and kindled animals. The mean duration of the burst was greatly prolonged in cells from kindled preparations. The depolarizing synaptic events underlying the burst response in the kindled and control animals could be examined when Mg2+ was increased to suppress but not block synaptic transmission. Electrical stimulation evoked a short-latency graded synaptic depolarization, followed by a long-latency all-or-none depolarizing event, which appeared to be involved in generating the burst response. Norepinephrine (NE), in a 4-microM concentration, reversibly blocked the burst responses in the control preparation. Burst responses elicited from kindled preparations were also suppressed by NE. For the latter cases, higher concentrations of NE were required to produce this effect. The alpha-2-agonist clonidine mimicked the suppressive action of NE on the evoked events. In contrast the beta-agonist isoproterenol facilitated the occurrence of spontaneous synchronous bursts and prolonged evoked burst discharges in both the control and kindled preparations. NE and clonidine block the burst response by suppressing the underlying synaptic events. The facilitatory action of isoproterenol on spontaneous and evoked responses suggests that NE may also exert an excitatory effect.

A Novel Interleukin-IL-6 (IL-6) Dependent Syngeneic Multiple Myeloma (MM) Model in SCID Mice.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4891-4891
Author(s):  
Mohamed H. Zaki ◽  
Zhao Zhou ◽  
Francis L. McCabe ◽  
Hillary J. Millar ◽  
Christine McCauley ◽  
...  
Keyword(s):  
Cell Line ◽  
Tumor Volume ◽  
Plasma Cells ◽  
Treated Group ◽  
Scid Mice ◽  
Tumor Bearing ◽  
The Mean ◽  
And Control

Abstract IL-6 is a multifunctional cytokine that is implicated in the pathophysiology of several malignant diseases including MM, an incurable malignant plasma cell disorder. IL-6 is known to enhance proliferation, differentiation and survival of malignant plasma cells in MM through an autocrine and/or a paracrine mechanism that involves the inhibition of apoptosis of the malignant cells, induction of resistance to chemotherapy and contribution to angiogenesis. Moreover, elevated levels of IL-6 in serum of patients with MM correlate with disease activity, unfavorable prognosis and refractoriness to standard therapy. Blocking IL-6 has been postulated to be an effective therapy (Klein et al, 1995) and several studies have investigated the effect of blocking IL-6 on MM cells and cell lines both in vitro and in vivo. However, the lack of a reliable IL-6 dependent MM model has hindered these efforts. Recently, mouse plasmacytomas were described as appropriate models to study the biology of human MM (Iankov et al., Immunobiology2004; 208(5)). The current study describes a new in vivo IL-6 dependent mouse plasmacytoma model in SCID mice. Mice were inoculated subcutaneously with 1 x 106 7TD1 cells, an IL-6 dependent mouse hybridoma/plasmacytoma cell line. Three days after tumor inoculation, mice were treated 2x/week i.p. with either PBS or 25 mg/kg of anti-mouse IL-6 (R & D systems, Clone MP520F3) or control mAb. Thirteen days after tumor implantation the mean tumor volume in the control mAb group and PBS group was 3204 +/− 360 SEM mm3, n = 10; and 2430 +/− 189 SEM mm3, n = 10, respectively. The mean tumor volume in the anti-IL-6 treated group was 635 +/− 149 SEM mm3, n = 10. Serum was tested by ELISA for levels of IL-6 and IgM (a mAb that is produced by 7TD1 cell line). IL-6 serum level was undetectable in naïve non-tumor bearing SCID mice. The IL-6 levels in the PBS treated group and control mAb group were 121 +/− 32 pg/ml and 125 +/− 14 pg/ml, respectively. IL-6 levels in animals treated with rat-anti- mouse IL-6 were not detected due to interference of the mAb with the ELISA. Serum IgM levels in optical density (OD) were 0.02 +/− 0.005 in the naïve non-tumor bearing animals, 0.80 +/− 0.02 in the PBS group, 0.77 +/− 0.03, in the control mAb group, and 0.19 +/− 0.17 in the rat anti-mouse IL-6 group. In conclusion the current study showed that 7TD1cells could be grown in SCID mice. Serum levels of both IgM and IL-6 were significantly elevated in the PBS and control mAb treated tumor-bearing animals. There was a significant reduction in the IgM levels in the rat anti-mouse IL-6 treated group (P <0.0001), a positive correlation between final tumor weight and serum IgM level (P < 0.0001, r2 = 0.782) and a 74% inhibition of tumor growth relative to either control mAb or vehicle control (P <0.0001). Taken together the current study introduces a new IL-6 dependant mouse plasmacytoma model that can be used to study the biology of MM and to test the efficacy of IL-6 blocking agents in vivo.

scholarly journals Morphologic changes in boar sperm nuclei with reduced disulfide bonds in electrostimulated porcine oocytes

Reproduction ◽  
2006 ◽  
Vol 131 (3) ◽  
pp. 603-611 ◽  
Author(s):  
Michiko Nakai ◽  
Naomi Kashiwazaki ◽  
Akiko Takizawa ◽  
Naoki Maedomari ◽  
Manabu Ozawa ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Blastocyst Stage ◽  
Blastocyst Formation ◽  
The Mean ◽  
Sperm Nuclei ◽  
Morphologic Changes ◽  
Number Of Cells ◽  
Stimulation Of ◽  
Nuclear Decondensation

In pigs, failure of sperm nuclear decondensation has been reported after injection into oocytes. We examined the effects of pretreating sperm heads with Triton X-100 (TX-100) and dithiothreitol (DTT) and of electrical stimulation of oocytes after sperm head injection on time-dependent morphologic changes in sperm nuclei andin vitrodevelopment to the blastocyst stage. In experiment 1, spermatozoa were pretreated with 1% TX-100 and 5 mM DTT (T + D) or not treated, and then injected intoin vitromatured oocytes. Electrical stimulation (1.5 kV/cm, 20 μs DC pulse) was applied to the oocytes 1 h after injection (stimulated group) or was not applied (unstimulated group). Some of the oocytes in each group were evaluated at hourly intervals until 10 h after injection for morphologic changes in the sperm nuclei. Unstimulated oocytes injected with untreated spermatozoa showed a delayed peak in the rate of nuclear decondensation (39.4–44.1%, 3–6 h after injection) compared with oocytes injected with T + D-treated spermatozoa (57.0% and 52.6%, 1 and 2 h, respectively). The rate of male pronucleus formation peaked 6 h after stimulation (by 40–60%) after injected oocytes had been stimulated with an electrical pulse, irrespective of whether or not the spermatozoa had been pretreated. In unstimulated oocytes, the rate of male pronucleus formation did not increase and stayed at the basal level (less than 20%) throughout the culture period, regardless of the sperm treatment. Thus, T + D treatment of spermatozoa did not affect completion of fertilization. In experiment 2, we evaluated the effects of electrical stimulation and sperm treatment with T + D on the rate of blastocyst formation and the mean number of cells per blastocyst. Oocytes stimulated after injection with either T + D-treated or untreated spermatozoa showed significantly higher percentages of blastocyst formation (24.8% and 27.1% respectively) than did unstimulated oocytes (1.1% and 4.1% for T + D-treated and untreated respectively;P< 0.01 by Duncan’s multiple-range test). The rate of blastocyst formation did not differ between the T + D-treated and untreated groups. The mean number of cells per blastocyst did not differ among any of the groups (14.0–29.4 cells). These results suggest that pretreatment of sperm with TX-100 and DTT shifted the timing of sperm nuclear decondensation forward. However, pronucleus formation and development to the blastocyst stagein vitrowere not improved by sperm treatment. Thus, electrical stimulation of injected oocytes enhancesin vitrodevelopment to the blastocyst stage in pigs.

scholarly journals Thyroid status and β-agonistic effects on cytosolic calcium concentrations in single rat cardiac myocytes activated by electrical stimulation or high-K+ depolarization

1990 ◽  
Vol 268 (3) ◽  
pp. 563-569 ◽  
Author(s):  
R E Beekman ◽  
C van Hardeveld ◽  
W S Simonides
Keyword(s):  
Electrical Stimulation ◽  
Steady State ◽  
Cardiac Tissue ◽  
Cytosolic Calcium ◽  
Beta Agonist ◽  
Thyroid Status ◽  
Beta Agonists ◽  
High K ◽  
The Mean ◽  
Rat Cardiac Myocytes

The effects of the thyroid status on the cytosolic free Ca2+ concentration ([Ca2+]i) in single cardiomyocytes were studied at rest and during contraction. The mean resting [Ca2+]i increased significantly from the hypothyroid (45 +/- 4 nM) through the euthyroid (69 +/- 12 nM) to the hyperthyroid condition (80 +/- 11 nM) at extracellular Ca2+ concentrations ([Ca2+]o) up to 2.5 mM. At [Ca2+]o above 2.5 mM the differences in [Ca2+]i between the groups became less. The amplitude of the Ca2+ transients became higher in all groups with increasing [Ca2+]o (1, 2.5 and 5 mM), and was highest at all [Ca2+]o in hyperthyroid myocytes. The beta-agonist isoprenaline elevated peak [Ca2+]i during contraction and increased the rate of the decay of the Ca2+ transients to a greater extent in hypothyroid myocytes than in hyperthyroid myocytes. Depolarization with high [K+]o induced a large but transient [Ca2+]i overshoot in hypothyroid myocytes, but not in hyperthyroid myocytes, before a new elevated steady-state [Ca2+]i was reached, which was not different between the groups. When isoprenaline was added to K+ o-depolarized myocytes after a steady state was reached, a significantly larger extra increase in [Ca2+]i was measured in the hypothyroid group (28%) compared with the hyperthyroid group (8%). It is concluded that in cardiac tissue exposed to increasing amounts of thyroid hormones (1) [Ca2+]i increases at rest and during contraction in cardiomyocytes and (2) interventions which favour Ca2+ entry into the cytosol [( Ca2+]o elevation, high [K+]o, beta-agonists) tend to have less impact on Ca2+ homoeostasis.

REDUCTION OF ANDROSTENEDIONE BY SKIN IN VITRO AND SERUM LEVELS OF GONADOTROPHINS AND ANDROGENS IN MEN WITH HYPOSPADIAS

1979 ◽  
Vol 82 (3) ◽  
pp. 395-401 ◽  
Author(s):  
JAN SVENSSON ◽  
PETER ENEROTH ◽  
JAN-ÅKE GUSTAFSSON ◽  
MARTIN RITZÉN ◽  
ÅKE STENBERG
Keyword(s):  
Reductase Activity ◽  
Serum Levels ◽  
Serum Concentrations ◽  
Scrotal Skin ◽  
Upper Arm ◽  
Control Subjects ◽  
The Mean ◽  
And Control ◽  
Mean Concentration

The reduction of 4-[1,2-3H]androstene-3,17-dione (androstenedione) in vitro by scrotal skin was measured in samples from nine men (16–34 years old) with hypospadias and from ten male control subjects. The reduction of androstenedione was also studied in axillary and upper arm skin of seven control subjects. Androstenedione was reduced to material with chromatographic characteristics of 5α-androstane-3,17-dione and to 3α- and 3β-hydroxy-5α-androstan-17-one. No difference in 5α-reductase activity (defined as the sum of these three metabolites formed) was found in scrotal skin from hypospadic and control men. The mean concentration of 5α-dihydrotestosterone in serum from men with hypospadias was lower than that in serum from control subjects (P< 0·01). The mean ratio of the serum concentrations of testosterone and 5α-dihydrotestosterone was higher in hypospadic men than in control subjects (P< 0·05). No differences between the two groups were found in the mean serum concentrations of LH, FSH, prolactin, dehydroepiandrosterone, androstenedione, testosterone or testosterone-binding globulin.

scholarly journals Effects of Preharvest Methyl Jasmonate Elicitation and Electrical Stimulation on Camptothecin Production by In Vitro Plants of Ophiorrhiza ridleyana Craib

2021 ◽  
Vol 11 (10) ◽  
pp. 4555
Author(s):  
Supakit Pisitpaibool ◽  
Suchada Sukrong ◽  
Kijchai Kanjanaprapakul ◽  
Muenduen Phisalaphong
Keyword(s):  
Tissue Culture ◽  
Electrical Stimulation ◽  
Methyl Jasmonate ◽  
Culture Medium ◽  
Solid Culture ◽  
Direct Electric Current ◽  
Solid Culture Medium ◽  
The Mean ◽  
Stems And Leaves

To enhance plant camptothecin (CPT) production in vitro, 5-month-old Ophiorrhiza ridleyana Craib plant cultures were treated with solutions of methyl jasmonate (MeJA) dissolved in ethanol, which were applied to the surface of the solid culture medium. It was demonstrated that the maximum CPT content in the tissue-cultured plants was achieved after 12 h elicitation with 50 µM MeJA. The mean CPT contents in roots and stems were 50.8 and 67.0 µg/g DW, respectively, which were approximately 1.8- and 2.6-fold higher, respectively, than those of the control. However, MeJA elicitation showed no significant effect on CPT accumulation in O. ridleyana leaves. Moreover, it was found that direct electric current (DC) stimulation also significantly increased CPT accumulation in O. ridleyana. The treatment with DC at 20 mA for 3 min of stimulation enhanced 3-fold the CPT content in roots, stems, and leaves to 41.9, 36.0 and 19.6 µg/g DW, respectively, which were approximately 1.5-, 1.7- and 1.4-fold higher, respectively, as compared to those of the control. The results demonstrate that preharvest treatment by MeJA elicitation and electrical stimulation can be beneficial for secondary metabolite production of CPT in tissue-culture plants of O. ridleyana.

scholarly journals Using a Digital Twin of an Electrical Stimulation Device to Monitor and Control the Electrical Stimulation of Cells in vitro

2021 ◽  
Vol 9 ◽  
Author(s):  
Julius Zimmermann ◽  
Kai Budde ◽  
Nils Arbeiter ◽  
Francia Molina ◽  
Alexander Storch ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Cellular Mechanisms ◽  
Temperature Changes ◽  
Digital Twin ◽  
Stimulation Parameters ◽  
Significant Temperature ◽  
And Control ◽  
Stimulation Of

Electrical stimulation for application in tissue engineering and regenerative medicine has received increasing attention in recent years. A variety of stimulation methods, waveforms and amplitudes have been studied. However, a clear choice of optimal stimulation parameters is still not available and is complicated by ambiguous reporting standards. In order to understand underlying cellular mechanisms affected by the electrical stimulation, the knowledge of the actual prevailing field strength or current density is required. Here, we present a comprehensive digital representation, a digital twin, of a basic electrical stimulation device for the electrical stimulation of cells in vitro. The effect of electrochemical processes at the electrode surface was experimentally characterised and integrated into a numerical model of the electrical stimulation. Uncertainty quantification techniques were used to identify the influence of model uncertainties on relevant observables. Different stimulation protocols were compared and it was assessed if the information contained in the monitored stimulation pulses could be related to the stimulation model. We found that our approach permits to model and simulate the recorded rectangular waveforms such that local electric field strengths become accessible. Moreover, we could predict stimulation voltages and currents reliably. This enabled us to define a controlled stimulation setting and to identify significant temperature changes of the cell culture in the monitored voltage data. Eventually, we give an outlook on how the presented methods can be applied in more complex situations such as the stimulation of hydrogels or tissue in vivo.

scholarly journals The Effect of Auriculotherapy on Pulmonary Findings and Sleep Quality in Patients with Covid 19

2021 ◽  
Author(s):  
Maryam Mohammadi ◽  
Zohreh AkhoundiMeybodi ◽  
Mahboubeh Valiani ◽  
Mohammad Sharifyazdi ◽  
Leila Asadi ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Electrical Stimulation ◽  
Sleep Quality ◽  
Demographic Characteristics ◽  
Time Data ◽  
Control Groups ◽  
Significant Difference ◽  
Before And After ◽  
The Mean ◽  
And Control

Abstract Background: Auriculotherapy is a sub-branch of acupuncture and is an effective method in acute and chronic diseases. Aim: The aim of this study was to evaluate the effect of Auriculotherapy on pulmonary findings and sleep quality in patients with Covid 19.Methods: The present study is a clinical trial study in which 70 hospitalized patients with Covid 19 with pulmonary findings and low sleep quality were randomly divided into intervention and control groups. Auriculotherapy was performed with electrical stimulation in one session and then Vakaria seed was placed in acupressure points and stimulated for one week (8 times a day for one minute each time). Data collection tools were checklist of pulmonary findings, Pittsburgh questionnaires and demographic characteristics.Results: The results showed that there was no significant difference between the mean SPO2 score in the two groups before and after the intervention (P = 0.09). There was a statistically significant difference between the mean score of dyspnea (P = 0.003), cough (P <0.008) and overall score of sleep quality in the two groups before and after the intervention (P <0.001).Conclusion: The results of this study showed that Auriculotherapy is effective on pulmonary improvements and sleep quality in patients with Covid 19.Trial registration: IRCT, IRCT20180608040007N2. Registered 13 June 2020, https://en.irct.ir/trial/48218.

Effect of embryo source and recipient progesterone environment on embryo development in cattle

2007 ◽  
Vol 19 (7) ◽  
pp. 861 ◽  
Author(s):  
P. Lonergan ◽  
A. Woods ◽  
T. Fair ◽  
F. Carter ◽  
D. Rizos ◽  
...  
Keyword(s):  
Artificial Insemination ◽  
Recovery Rate ◽  
In Vitro Maturation ◽  
Strong Support ◽  
Embryo Survival ◽  
Embryo Recovery ◽  
The Mean ◽  
And Control

The aim of the present study was to examine the effect of embryo source (in vivo v. in vitro) and the progesterone environment into which it was transferred on Day 7 on embryo survival and size on Day 13. Day 7 blastocysts were produced either in vivo using superovulation, artificial insemination and non-surgical embryo recovery or in vitro using in vitro maturation, fertilisation and culture. In order to produce animals with divergent progesterone concentrations, following synchronisation recipients were either superovulated (High progesterone; n = 10) or not (Control progesterone; n = 10). Ten blastocysts, produced either in vivo or in vitro, were transferred to each recipient on Day 7. Both groups were killed on Day 13. The mean progesterone concentration from Day 7 to Day 13 (the period when the embryos were in the uterus) in the High and Control progesterone recipients was 36.32 ± 1.28 and 10.30 ± 0.51 ng mL–1, respectively. Of the in vivo embryos transferred, the overall recovery rate at Day 13 was 64%, which was higher (P < 0.001) than that of 20% for the in vitro embryos transferred. The mean area of embryos recovered from High progesterone recipients was 3.86 ± 0.45 mm2 (n = 28) compared with 1.66 ± 0.38 mm2 (n = 24) for embryos recovered from Control progesterone recipients (P < 0.001). Similarly, the origin of the embryo used for transfer affected embryo size on Day 13. In summary, the recovery rate of blastocysts was higher for in vivo- than in vitro-derived embryos. Blastocyst size was approximately 2.3-fold greater in recipients with high compared with normal progesterone. The present study lends strong support to the hypothesis that an earlier rise in progesterone after conception stimulates blastocyst growth and the development of competent embryos.

scholarly journals Platelet Aggregability in Sleep-Related Stroke

1989 ◽  
Vol 16 (1) ◽  
pp. 71-77
Author(s):  
C.L. Voll ◽  
N. Chetty ◽  
P. Atkinson
Keyword(s):  
Stroke Onset ◽  
Control Groups ◽  
Nocturnal Sleep ◽  
Platelet Aggregability ◽  
Significant Difference ◽  
History Of ◽  
Circadian Fluctuation ◽  
The Mean ◽  
And Control

ABSTRACT:We examined platelet aggregability during nocturnal sleep and daytime wakefulness in patients with a history of sleep-related stroke onset (SOS) and compared it to that of matched awake-onset stroke (AOS) patients and controls without evidence of vascular disease. Aggregability was evaluated in-vitro at least seven weeks following stroke onset. Platelets were more aggregable to ADP, collagen and arachidonic acid (AA) during both sleep and wakefulness in patients with AOS (p<0.01). No significant difference in the mean aggregation thresholds during sleeping or waking periods were found between SOS and control groups. However, platelets were significantly more responsive to AA during sleep than during wakefulness in the SOS patients (p<0.01). This difference was confined to the subgroup of SOS patients who had experienced nocturnal as opposed to daytime sleep-related stroke onset, suggesting that the observed difference in platelet responsiveness to AA may be related to a circadian fluctuation in platelet aggregability rather than to a sleep-related fluctuation. Significant sleep-related changes in platelet aggregability were not identified in the other two groups.

Control of colonic motility using electrical stimulation to modulate enteric neural activity

2021 ◽  
Author(s):  
Bradley Barth ◽  
Lee Travis ◽  
Nick J Spencer ◽  
Warren M. Grill
Keyword(s):  
Electrical Stimulation ◽  
Refractory Period ◽  
Colonic Motility ◽  
Gastrointestinal Transit ◽  
Absolute Refractory Period ◽  
Refractory Periods ◽  
Colonic Motor ◽  
The Mean ◽  
Insight Into

Electrical stimulation of the enteric nervous system (ENS) is an attractive approach to modify gastrointestinal transit. Colonic motor complexes (CMCs) occur with a periodic rhythm, but the ability to elicit a premature CMC depends, at least in part, upon the intrinsic refractory properties of the ENS, which are presently unknown. The objectives of this study were to record myoelectric complexes (MCs, the electrical correlates of CMCs) in the smooth muscle and (i) determine the refractory periods of MCs, (ii) inform and evaluate closed-loop stimulation to repetitively evoke MCs, and (iii) identify stimulation methods to suppress MC propagation. We dissected the colon from male and female C57BL/6 mice, preserving the integrity of intrinsic circuitry while removing the extrinsic nerves, and measured properties of spontaneous and evoked MCs in vitro. Hexamethonium abolished spontaneous and evoked MCs, confirming the necessary involvement of the ENS for electrically-evoked MCs. Electrical stimulation reduced the mean interval between evoked and spontaneous CMCs (24.6 ± 3.5 vs 70.6 ± 15.7 s, p = 0.0002, n = 7). The absolute refractory period was 4.3 s (95% CI = 2.8 - 5.7 s, R2 = 0.7315, n = 8). Electrical stimulation applied during fluid distention-evoked MCs led to an arrest of MC propagation, and following stimulation, MC propagation resumed at an increased velocity (n = 9). The timing parameters of electrical stimulation increased the rate of evoked MCs and the duration of entrainment of MCs, and the refractory period provides insight into timing considerations for designing neuromodulation strategies to treat colonic dysmotility.

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