In vivo measurement of microvasculature: A method for repeated and reproducible quantitation during long-term experiments

AbstractThe bladder, stomach, intestines, heart, and lungs all move dynamically to achieve their purpose. A long-term implantable device that can attach onto an organ, sense its movement, and deliver current to modify the organ function would be useful in many therapeutic applications. The bladder, for example, is a smooth muscle organ that can suffer from incomplete contractions that result in urinary retention with patients requiring using catheterization. Those affected may benefit from a combination of strain sensor and electrical stimulator to better control bladder emptying. We describe the materials and design of such a device made from thin layer carbon nanotube (CNT) and Ecoflex 00-50 and demonstrate its function with in vivo feline bladders. During bench-top characterization, the resistive and capacitive sensors exhibited reliable output throughout 5,000 stretching cycles under physiology condition. In vivo measurement with piezoresistive device showed a high correlation between sensor resistance and volume. Stimulation driven from Pt-PDMS composite electrodes successfully induced bladder contraction. We present method for reliable connection and packaging of medical grade wire to the CNT device. This work is an important step toward the translation of low-durometer elastomers, stretchable CNT percolation and Pt-PDMS composite, which are ideal for large strain bioelectric applications to sense or modulate dynamic organ states.

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MONOCLONAL ANTIBODY-MEDIATED ENHANCEMENT OF GROWTH HORMONE ACTIVITY IN VIVO

Journal of Endocrinology ◽

10.1677/joe.0.107r009 ◽

1985 ◽

Vol 107 (3) ◽

pp. R9-R12 ◽

Cited By ~ 41

Author(s):

A. T. Holder ◽

R. Aston ◽

M.A. Preece ◽

J. Ivanyi

Keyword(s):

Monoclonal Antibody ◽

Hormone Activity ◽

Short Term ◽

Long Term Experiments ◽

Snell Dwarf ◽

New Perspective ◽

Dwarf Mice ◽

Dose Dependent

ABSTRACT This work demonstrates that complexing hGH with monoclonal antibody EBl (MAB-EBl) can produce a striking potentiation of the somatogenic actions of hGH in vivo in Snell dwarf mice. In short-term experiments significant increases in cartilage metabolism and body weight were noted; these responses were dose-dependent for both MAB-EBl and hGH concentration. Increased growth was also observed in long-term experiments. In marmosets where MAB-EBl cross-reacts with endogenous GH, MAB-EBl alone enhanced the actions of endogenous GH. A new perspective may be necessary to incorporate these results into the current concept of antibody action.

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Of streaming hepatocytes and meandering sinusoids

Human & Experimental Toxicology ◽

10.1177/096032719401300905 ◽

1994 ◽

Vol 13 (9) ◽

pp. 604-605

Author(s):

Alan J Paine

Keyword(s):

Escherichia Coli ◽

Stem Cells ◽

Gene Transfer ◽

Marker Gene ◽

Nuclear Localisation Signal ◽

Adult Rat ◽

Long Term Experiments ◽

One Year

The fate of normal hepatocytes in adult rat liver was studied after genetic labelling using the Escherichia coli β-galactosidase gene coupled to a nuclear localisation signal. The marker gene was introduced by direct in vivo retroviral-mediated gene transfer into hepatocytes 24 h after partial hepatectomy. Analysis of β-galactosidase expression in the liver at various times after gene transfer revealed that labelled hepatocytes were distributed throughout the entire lobule with a predominance in the periportal and mediolobular regions. Long-term experiments demonstrated that division of hepatocytes did occur as was revealed by the increasing number of β-galactosidase-positive cells in isolated clusters. There was no evidence for the participation of stem cells in this process. Moreover, we found that after more than one year, the pattern of distribution of positive cells within the lobule was not modified. This suggests that hepatocytes do not migrate from the portal space to the perivenous region, as has been previously hypothesised.

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In Vivo Measurement of Long-Term Laser Induced Retinal Temperature Rise

IEEE Transactions on Biomedical Engineering ◽

10.1109/tbme.1980.326701 ◽

1980 ◽

Vol BME-27 (11) ◽

pp. 617-622 ◽

Cited By ~ 5

Author(s):

Garrett D. Polhamus

Keyword(s):

Temperature Rise ◽

In Vivo Measurement

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Preclinical progress and first translational steps for a liposomal chemotherapy protocol against adrenocortical carcinoma

Endocrine Related Cancer ◽

10.1530/erc-16-0249 ◽

2016 ◽

Vol 23 (10) ◽

pp. 825-837 ◽

Cited By ~ 5

Author(s):

Sara Jung ◽

Zoltan Nagy ◽

Martin Fassnacht ◽

Gerard Zambetti ◽

Max Weiss ◽

...

Keyword(s):

Clinical Data ◽

Adrenocortical Carcinoma ◽

Therapy Monitoring ◽

Treatment Options ◽

Histological Evaluation ◽

Circulating Microrna ◽

Long Term Experiments ◽

Chemotherapy Protocol

Systemic therapy of adrenocortical carcinoma (ACC) is limited by heterogeneous tumor response and adverse effects. Recently, we demonstrated anti-tumor activity of LEDP-M (etoposide, liposomal doxorubicin, liposomal cisplatin, mitotane), a liposomal variant of EDP-M (etoposide, doxorubicin, cisplatin, mitotane). To improve the therapeutic efficacy and off-target profiles of the clinical gold standard EDP-M, we investigated liposomal EDP-M regimens in different preclinical settings and in a small number of ACC patients with very advanced disease. Short- and long-term experiments were performed on two ACC models (SW-13 and SJ-ACC3) in vivo. We evaluated the anti-tumoral effects and off-target profiles of EDP-M, LEDP-M and a novel regimen L(l)EDP-M including liposomal etoposide. Furthermore, the role of plasma microRNA-210 as a therapeutic biomarker and first clinical data were assessed. Classical and liposomal protocols revealed anti-proliferative efficacy against SW-13 (EDP-M P < 0.01; LEDP-M: P < 0.001; L(l)EDP-M: P < 0.001 vs controls), whereas in SJ-ACC3, only EDP-M (P < 0.05 vs controls) was slightly effective. Long-term experiments in SW-13 demonstrated anti-tumor efficacy for all treatment schemes (EDP-M: P < 0.01, LEDP-M: P < 0.05, L(l)EDP-M P < 0.001 vs controls). The analysis of pre-defined criteria leading to study termination revealed significant differences for control (P < 0.0001) and EDP-M (P = 0.003) compared to L(l)EDP-M treatment. Raising its potential for therapy monitoring, we detected elevated levels of circulating microRNA-210 in SW-13 after LEDP-M treatment (P < 0.05). In contrast, no comparable effects were detectable for SJ-ACC3. However, overall histological evaluation demonstrated improved off-target profiles following liposomal regimens. The first clinical data indicate improved tolerability of liposomal EDP-M, thus confirming our results. In summary, liposomal EDP-M regimens represent promising treatment options to improve clinical treatment of ACC.

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Comparison of Grass Silage and Whole Crop Fodder Beet Silage When Fed to Ewes in Late Pregnancy

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s0308229600024739 ◽

1993 ◽

Vol 1993 ◽

pp. 148-148

Author(s):

J.V. O'Doherty ◽

P.J. Quinn ◽

T.F. Crosby

Keyword(s):

Late Pregnancy ◽

High Quality ◽

Fodder Beet ◽

Treatment Groups ◽

Grass Silage ◽

Long Term Experiments ◽

Feeding Value ◽

Cattle And Sheep

The use of fodder beet in rations fed to cattle and sheep has always been valued highly. Recent long-term experiments have shown that the palatability and high feeding value of fodder beet is fully preserved during the ensiling process.The objective of this experiment was to evaluate the performance of ewes in late pregnancy when fed either whole crop fodderbeet silage or grass silage.Mature (2-7 yrs), oestrous synchronised, twin bearing ewes (n=60) of mixed breeds (mainly Suffolk cross, greyface and halfbred), were selected following winter shearing and pregnancy scanning in December. At ten weeks prior to the predicted mean lambing date, the ewes were allocated to one of two treatment groups which were balanced for breed, age and liveweight. High quality precission chopped silage (DM 194 g/kg; CP 152 g/kg DM; in vivo ME 12.8 MJ/kg DM) and whole crop fodderbeet silage (WCFB)(DM 171 g/kg; CP126 g/kg DM; in vivo ME 11.7 MJ/kg DM) were fed in Tl and T2 respectively.

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EFFECTS OF CONTRACTILE STIMULI ON EXCHANGES OF ELECTROLYTES BETWEEN UTERINE TISSUES AND A SALINE–BICARBONATE MEDIUM

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y59-015 ◽

1959 ◽

Vol 37 (1) ◽

pp. 127-148

Author(s):

Edwin E. Daniel ◽

Betty N. Daniel

Keyword(s):

Smooth Muscle ◽

Glycogen Content ◽

Concomitant Increase ◽

Sodium Permeability ◽

Potassium Loss ◽

Clear Cut ◽

Long Term Experiments ◽

Tissue Sodium

(1) Evidence has been presented suggesting that progesterone pretreatment in vivo increases the rate of leakage of potassium from rabbit uterine segments into a saline–bicarbonate medium.(2) Various types of evidence indicate that in uterine tissues, the loss of potassium from cells into potassium-free solutions is increased during the contractile actions of drugs. There was no clear-cut concomitant increase in tissue sodium concentrations. The results tend to confirm previous findings indicating that increases in potassium (but not in sodium) permeability are associated with contraction of smooth muscle.(3) Epinephrine effects on potassium loss occurred only in uteri which contracted in response to epinephrine. Norepinephrine, but not iproterenol, had a similar effect. Dibenamine, alone, decreased potassium loss and partly blocked the effects of epinephrine. Direct measurement of glycogen content suggested that these findings were not related to a glycogenolytic action of the epinephrine. Rather, the effect of epinephrine to increase potassium loss seemed to be closely related to its contractile action. In long-term experiments, both epinephrine and calcium slowed the rate of K loss and of water and sodium gain. This effect also was absent in uterine tissues which were not contracted by epinephrine.

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EFFECTS OF CONTRACTILE STIMULI ON EXCHANGES OF ELECTROLYTES BETWEEN UTERINE TISSUES AND A SALINE–BICARBONATE MEDIUM

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o59-015 ◽

1959 ◽

Vol 37 (1) ◽

pp. 127-148 ◽

Cited By ~ 6

Author(s):

Edwin E. Daniel ◽

Betty N. Daniel

Keyword(s):

Smooth Muscle ◽

Glycogen Content ◽

Concomitant Increase ◽

Sodium Permeability ◽

Potassium Loss ◽

Clear Cut ◽

Long Term Experiments ◽

Tissue Sodium

(1) Evidence has been presented suggesting that progesterone pretreatment in vivo increases the rate of leakage of potassium from rabbit uterine segments into a saline–bicarbonate medium.(2) Various types of evidence indicate that in uterine tissues, the loss of potassium from cells into potassium-free solutions is increased during the contractile actions of drugs. There was no clear-cut concomitant increase in tissue sodium concentrations. The results tend to confirm previous findings indicating that increases in potassium (but not in sodium) permeability are associated with contraction of smooth muscle.(3) Epinephrine effects on potassium loss occurred only in uteri which contracted in response to epinephrine. Norepinephrine, but not iproterenol, had a similar effect. Dibenamine, alone, decreased potassium loss and partly blocked the effects of epinephrine. Direct measurement of glycogen content suggested that these findings were not related to a glycogenolytic action of the epinephrine. Rather, the effect of epinephrine to increase potassium loss seemed to be closely related to its contractile action. In long-term experiments, both epinephrine and calcium slowed the rate of K loss and of water and sodium gain. This effect also was absent in uterine tissues which were not contracted by epinephrine.

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