Investigation of the Thermal and Injury Behavior During Microwave Thermal Therapy of Porcine Kidney

Author(s):  
Xiaoming He ◽  
Shawn Mcgee ◽  
James E. Coad ◽  
Paul A. Iaizzo ◽  
David J. Swanlund ◽  
...  

In this paper, we report on the characterization of microwave therapy of normal porcine kidneys both in vitro and in vivo. This technology is being developed for eventual use in the treatment of small renal cell carcinoma (RCC) by minimally invasive procedures. During experiments, microwave energy was applied through an interstitial microwave probe (Urologix, Plymouth, MN) to the kidney cortex with occasional involvement of the kidney medulla. The thermal histories at several locations were recorded. After treatment, the kidneys were bisected and small tissue slices were cut out at approximately the same depth as the thermal probes. The tissue slices were further processed for histological study. Both cellular injury and the area of microvascular stasis were quantitatively evaluated by histology. Absolute rate kinetic models of cellular injury and vascular stasis were developed and fit to this data. A 3-D finite element thermal model based on the Pennes Bioheat equation was developed and solved using a commercial software package (ANSYS, V5.7). The Specific Absorption Rate (SAR) of the microwave probe was measured experimentally in tissue equivalent gel-like solution. The thermal model was first validated by the measured in vitro thermal histories. It was then used to determine the blood perfusion term in vivo.

1997 ◽  
Vol 272 (3) ◽  
pp. L479-L485 ◽  
Author(s):  
M. Ikegami ◽  
T. R. Korfhagen ◽  
M. D. Bruno ◽  
J. A. Whitsett ◽  
A. H. Jobe

In the present study we asked if surfactant metabolism was altered in surfactant protein (SP) A-deficient mice in vivo. Although previous studies in vitro demonstrated that SP-A modulates surfactant secretion and reuptake by type II cells, mice made SP-A deficient by homologous recombination grow and reproduce normally and have normal lung function. Alveolar and lung tissue saturated phophatidylcholine (Sat PC) pools were 50 and 26% larger, respectively, in SP-A(-/-) mice than in SP-A(+/+) mice. Radiolabeled choline and palmitate incorporation into lung Sat PC was similar both in vivo and for lung tissue slices in vitro from SP-A(+/+) and SP-A(-/-) mice. Percent secretion of radiolabeled Sat PC was unchanged from 3 to 15 h, although SP-A(-/-) mice retained more labeled Sat PC in the alveolar lavages at 48 h (consistent with the increased surfactant pool sizes). Clearance of radiolabeled dipalmitoylphosphatidylcholine and SP-B from the air spaces after intratracheal injection was similar in SP-A(-/-) and SP-A(+/+) mice. Lack of SP-A had minimal effects on the overall metabolism of Sat PC or SP-B in mice.


2021 ◽  
Vol 17 (9) ◽  
pp. 1812-1823
Author(s):  
Fei Liu ◽  
Xinyu Wang ◽  
Shujun Li ◽  
Yiheng Liao ◽  
Xinxin Zhan ◽  
...  

Ti–24Nb–4Zr–8Sn (Ti2448) alloys, with a relatively low elastic modulus and unique mechanical properties, are desirable materials for oral implantation. In the current study, a multifaceted strontium-incorporating nanotube coating was fabricated on a Ti2448 alloy (Ti2-NTSr) through anodization and hydrothermal procedures. In vitro, the Ti2-NTSr specimens demonstrated better osteogenic properties and more favorable osteoimmunomodulatory abilities. Moreover, macrophages on Ti2-NTSr specimens could improve the recruitment and osteogenic differentiation of osteoblasts. In vivo, dense clots with highly branched, thin fibrins and small pores existed on the Ti2-NTSr implant in the early stage after surgery. Analysis of the deposition of Ca and P elements, hard tissue slices and the bone-implant contact rate (BIC%) of the Ti2-NTSr implants also showed superior osseointegration. Taken together, these results demonstrate that the Ti2-NTSr coating may maximize the clinical outcomes of Ti2448 alloys for implantation applications.


1999 ◽  
Vol 276 (1) ◽  
pp. F164-F171 ◽  
Author(s):  
Kazuko Sagawa ◽  
Heini Murer ◽  
Marilyn E. Morris

Decreased serum sulfate concentrations are observed in hypothyroid patients. However, the mechanism involved in thyroid hormone-induced alterations of renal sulfate homeostasis is unknown. The objectives of this investigation were to determine the effect of 6-propyl-2-thiouracil (PTU)-induced hypothyroidism in rats on 1) the in vivo serum concentrations, renal clearance, and renal reabsorption of sulfate, 2) the in vitro renal transport in brush-border membrane (BBM) and basolateral membrane (BLM) vesicles, and 3) the cellular mechanism of the hypothyroid-induced alteration in sulfate renal transport. Serum sulfate concentrations, renal fractional reabsorption of sulfate, and creatinine clearance were decreased significantly in the hypothyroid group. The V max values for sodium-sulfate cotransport in BBM were significantly decreased in the kidney cortex from the hypothyroid animals (0.90 ± 0.31 vs. 0.49 ± 0.08 nmol ⋅ mg−1 ⋅ 10 s−1, n = 5–6, P < 0.05) without changes in K m. There were no significant differences in V max and K m for sulfate/anion exchange transport in BLM. Sodium-dependent sulfate transporter (NaSi-1) mRNA and protein levels were significantly lower in the kidney cortex from hypothyroid rats. Hypothyroidism did not alter the membrane motional order (fluidity) in BBM and BLM, which indicates that the changes in the membrane fluidity do not represent the mechanism for the altered renal transport. These results demonstrate that PTU-induced hypothyroidism decreases sodium-sulfate cotransport by downregulation of the NaSi-1 gene.


1988 ◽  
Vol 15 (3) ◽  
pp. 377 ◽  
Author(s):  
TD Ugalde ◽  
DJ Chalmers ◽  
PH Jerie

Acid invertase (β-fructofuranosidase, EC 3.2.1.26) was extracted from peach mesocarp (Prunus persica (L.) Batsch) using a range of extraction conditions. The enzyme always was attached to insoluble particles in the crude homogenate and was bound by a mechanism that could not have arisen during extraction. The activity in the insoluble fraction made up (essentially) all of the total activity extracted from the tissue and was the same as the activity shown by whole tissue slices placed directly into the assay solution. These results demonstrate that most of the acid invertase in developing peach mesocarp is located outside the cell. The amount of this enzyme, as measured in vitro, did not change during development at times when the rate of dry matter increase was changing rapidly. Either the action of intercellular invertase is not associated with the control of dry matter accumulation in peach mesocarp, or control is effected through activity of the enzyme in vivo, not its synthesis or degradation.


2000 ◽  
Vol 278 (4) ◽  
pp. F613-F619 ◽  
Author(s):  
Alexander Shigaev ◽  
Carol Asher ◽  
Hedva Latter ◽  
Haim Garty ◽  
Eitan Reuveny

Aldosterone is the major corticosteroid regulating Na+ absorption in tight epithelia and acts primarily by activating the epithelial Na+ channel (ENaC) through unknown induced proteins. Recently, it has been reported that aldosterone induces the serum- and glucocorticoid-dependent kinase sgk and that coexpressing ENaC with this kinase in Xenopus laevis oocytes increases the amiloride-sensitive Na+current (Chen SY, Bhargava A, Mastroberardino L, Meijer OC, Wang J, Buse P, Firestone GL, Verrey F, and Pearce D. Proc Natl Acad Sci USA 96: 2514–2519, 1999). The present study was done to further characterize regulation of sgk by aldosterone in native mammalian epithelia and to examine its effect on ENaC. With both in vivo and in vitro protocols, an almost fivefold increase in the abundance of sgk mRNA has been demonstrated in rat kidney and colon but not in lung. Induction of sgk by aldosterone was detected in kidney cortex and medulla, whereas the papilla expressed a constitutively high level of the kinase. The increase in sgkmRNA was detected as early as 30 min after the hormonal application and was independent of de novo protein synthesis. The observed aldosterone dose-response relationships suggest that the response is mediated, at least in part, by occupancy of the mineralocorticoid receptor. Coexpressing sgk and ENaC in Xenopus oocytes evoked a fourfold increase in the amiloride-blockable Na+ channel activity. A point mutation in the β-subunit known to impair regulation of the channel by Nedd4 (Y618A) had no significant effect on the response to sgk.


2004 ◽  
Vol 34 (3) ◽  
pp. 495-501 ◽  
Author(s):  
Sheyla Farhayldes Souza Domingues ◽  
Luiz Viana Diniz ◽  
Sonia Helena Costa Furtado ◽  
Otavio Mitio Ohashi ◽  
David Rondina ◽  
...  

The present study aimed to obtain quanti-qualitative data about the follicular ovarian population in Cebus apella females. Seven ovaries were obtained from 4 C. apella adult females. The ovaries were subjected to light microscopy. The number of preantral and antral follicles for each ovary was estimated using the Fractionator method. The preantral follicles were classified into primordial, transitional, primary and secondary follicles. Antral follicles were those that presented an antral cavity. All counted follicles were classified as normal or degenerated. The diameter of the follicles, oocytes and their nuclei were determined to accompany the follicular development. All results were represented as mean ± SE. The number of preantral follicles was 56,938 ± 21,888 and 49,133 ± 26,896 for the right and left ovaries, respectively. The percentage of normal follicles was 80 ± 4.95%. The follicular diameter ranged from 22 ± 0.5 µm to 61.2 ± 4.0 µm. Regarding the antral follicles, the number of normal and degenerate follicles per ovary were 60.0 ± 19.0 and 3 ± 1.8 follicles, respectively. The antral follicular diameter was 514.4 + 56.6 µm. In conclusion, the information obtained in this study can be used as a parameter for subsequent in vivo or in vitro studies about folliculogenesis in non-human neotropical primates of the C. apella species.


Blood ◽  
2012 ◽  
Vol 120 (17) ◽  
pp. 3436-3443 ◽  
Author(s):  
Yan Li ◽  
Feng Lin

Abstract Despite the potent immunosuppressive activity that mesenchymal stem cells (MSCs) display in vitro, recent clinical trial results are disappointing, suggesting that MSC viability and/or function are greatly reduced after infusion. In this report, we demonstrated that human MSCs activated complement of the innate immunity after their contact with serum. Although all 3 known intrinsic cell-surface complement regulators were present on MSCs, activated complement overwhelmed the protection of these regulators and resulted in MSCs cytotoxicity and dysfunction. In addition, autologous MSCs suffered less cellular injury than allogeneic MSCs after contacting serum. All 3 complement activation pathways were involved in generating the membrane attack complex to directly injure MSCs. Supplementing an exogenous complement inhibitor, or up-regulating MSC expression levels of CD55, one of the cell-surface complement regulators, helped to reduce the serum-induced MSC cytotoxicity. Finally, adoptively transferred MSCs in complement deficient mice or complement-depleted mice showed reduced cellular injury in vivo compared with those in wild type mice. These results indicate that complement is integrally involved in recognizing and injuring MSCs after their infusion, suggesting that autologous MSCs may have ad-vantages over allogeneic MSCs, and that inhibiting complement activation could be a novel strategy to improve existing MSC-based therapies.


1975 ◽  
Vol 64 (3) ◽  
pp. 557-571 ◽  
Author(s):  
G Shore ◽  
G A Maclachlan

Membrane preparations from growing regions of 8-day old Pisum sativum epicotyls contain multiple beta-1,4-glucan (cellulose) synthetase activities (UDP- or GDP-glucose: beta-1,4-glucan-glucosyl transferase), and the levels of some of these are influenced by treatments with the growth hormone, indoleacetic acid (IAA). When membranes from control epicotyl segments (zero time) are fractionated by isopycnic sedimentation in sucrose density gradients, all of the synthetase activities are associated mainly with Golgi membrane (density 1.55 g/cm3). After decapitation and treatment of epicotyls with IAA, synthetases also appear in a smooth vesicle fraction (density 1.11 g/cm3) which is rich in endoplasmic reticulum (ER) marker enzyme. Major fractions of these synthetases are not recovered in association with plasma membrane or washed cell walls. When [14-C]sucrose is supplied in vivo to segments +/- IAA, radioactive cellulose is deposited only in the wall. Cellulose or cellodextrin precursors do not accumulate in those membranes in which synthetase activities are recovered in vitro. In experiments where tissue slices containing intact cells are supplied with [14C]sugar nucleotide in vitro, alkali-insoluble beta-1,4-glucan is synthesized (presumably outside the protoplast) at rates which greatly exceeded (20-30 times) those obtained using isolated membrane preparations. Progressive disruption of cell structure results in increasing losses of this high activity. These results are consistent with the interpretation that Golgi and ER-associated synthetases are not themselves loci for cellulose synthesis in vivo, but represent enzymes in transit to sites of action at the wall:protoplast omterface. There they operate only if integrity of cellular organization is maintained.


2021 ◽  
Vol 22 (22) ◽  
pp. 12521
Author(s):  
Estefanía Moreno-Gordaliza ◽  
Maria Dolores Marazuela ◽  
Óscar Pastor ◽  
Alberto Lázaro ◽  
María Milagros Gómez-Gómez

Nephrotoxicity is a major complication of cisplatin-based chemotherapy, leading to acute kidney injury in ca. 30% of patients, with no preventive intervention or treatment available for clinical use. Cilastatin has proved to exert a nephroprotective effect for cisplatin therapies in in vitro and in vivo models, having recently entered clinical trials. A deeper understanding at the molecular level of cisplatin-induced renal damage and the effect of potential protective agents could be key to develop successful nephroprotective therapies and to establish new biomarkers of renal damage and nephroprotection. A targeted lipidomics approach, using LC-MS/MS, was employed for the quantification of 108 lipid species (comprising phospholipids, sphingolipids, and free and esterified cholesterol) in kidney cortex and medulla extracts from rats treated with cisplatin and/or cilastatin. Up to 56 and 63 lipid species were found to be altered in the cortex and medulla, respectively, after cisplatin treatment. Co-treatment with cilastatin attenuated many of these lipid changes, either totally or partially with respect to control levels. Multivariate analysis revealed that lipid species can be used to discriminate renal damage and nephroprotection, with cholesterol esters being the most discriminating species, along with sulfatides and phospholipids. Potential diagnostic biomarkers of cisplatin-induced renal damage and cilastatin nephroprotection were also found.


2019 ◽  
Vol 53 (3) ◽  
pp. 154-164 ◽  
Author(s):  
Somchit Eiam-Ong ◽  
Mookda Chaipipat ◽  
Krissanapong Manotham ◽  
Somchai Eiam-Ong

AbstractObjectives. Aldosterone rapidly enhances protein kinase C (PKC) alpha and beta1 proteins in the rat kidney. The G protein-coupled receptor 30 (GPR30)-mediated PKC pathway is involved in the inhibition of the potassium channel in HEK-239 cells. GPR30 mediates rapid actions of aldosterone in vitro. There are no reports available regarding the aldosterone action on other PKC isoforms and GPR30 proteins in vivo. The aim of the present study was to examine rapid actions of aldosterone on protein levels of phosphorylated PKC (p-PKC) delta, p-PKC epsilon, and GPR30 simultaneously in the rat kidney.Methods. Male Wistar rats were intraperitoneally injected with normal saline solution or aldosterone (150 µg/kg body weight). After 30 minutes, abundance and immunoreactivity of p-PKC delta, p-PKC epsilon, and GPR30 were determined by Western blot analysis and immunohisto-chemistry, respectively.Results. Aldosterone administration significantly increased the renal protein abundance of p-PKC delta by 80% (p<0.01) and decreased p-PKC epsilon protein by 50% (p<0.05). Aldosterone injection enhanced protein immunoreactivity of p-PKC delta but suppressed p-PKC epsilon protein intensity in both kidney cortex and medulla. Protein abundance of GPR30 was elevated by aldosterone treatment (p<0.05), whereas the immunoreactivity was obviously changed in the kidney cortex and inner medulla. Aldosterone translocated p-PKC delta and GPR30 proteins to the brush border membrane of proximal convoluted tubules.Conclusions. This is the first in vivo study simultaneously demonstrating that aldosterone administration rapidly elevates protein abundance of p-PKC delta and GPR30, while p-PKC epsilon protein is suppressed in rat kidney. The stimulation of p-PKC delta protein levels by aldosterone may be involved in the activation of GPR30.


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