Structural and functional characteristics of muscle from diabetic rodent small intestine

1990 ◽  
Vol 258 (5) ◽  
pp. G690-G698 ◽  
Author(s):  
T. V. Nowak ◽  
B. Harrington ◽  
J. P. Weisbruch ◽  
J. H. Kalbfleisch

After 30 days of streptozotocin-induced diabetes, the small intestine from untreated diabetic, insulin-treated diabetic, and nondiabetic rodents was excised in toto and measured. Despite a net loss in body weight, the diabetic animals showed a near twofold increase in small intestinal weight. This was characterized by a 148% increase in mucosal mass as well as a 39% increase in intestinal smooth muscle mass (P less than 0.05, respectively). The diabetic intestine was significantly longer and had a greater diameter and surface area. Diabetes significantly increased mucosal mass per unit surface area but produced an insignificant decrease in smooth muscle mass per unit surface area. Insulin treatment of the diabetic animals prevented the increase in total mucosal mass and mucosal mass per unit surface area. Insulin treatment also prevented the increase in smooth muscle mass, but reduced smooth muscle mass per unit surface area to a level significantly less than that found in nondiabetic intestine. In vitro dose-response studies of circular and longitudinal small intestinal muscle from the diabetic animals showed normal tension development and sensitivity to both bethanechol chloride and physostigmine. These observations show that the diabetic state produces alterations in not only mucosal but also smooth muscle mass in the small intestine. However, despite these morphological changes, diabetic intestinal smooth muscle retains its sensitivity to cholinergic stimulation and its capacity for tension generation.

2001 ◽  
Vol 120 (5) ◽  
pp. A534-A534
Author(s):  
A ZHAO ◽  
D MULLOY ◽  
J URBANJR ◽  
W GAUSE ◽  
T SHEADONOHUE

1975 ◽  
Vol 229 (5) ◽  
pp. 1268-1276 ◽  
Author(s):  
TY El-Sharkawy ◽  
EE Daniel

Some important features of the intracellularly recorded electrical control activity of rabbit jejunal smooth muscle and its temperature dependence are reported in this study. This activity consisted of repetitive 18-mV depolarizations (control potentials (CP) or slow waves), which at 37degreesC lasted 2 s and had a frequency of 18/min and arose from a membrane potential of --55 mV. In some cells periods between CP's exhibited "diastolic" progressive depolarizations (intercontrol-potential depolarization), which may be the trigger of the CP in driving cells. While CP was usually monophasic, some cells persistently exhibited a notch early in the plateau phase. We suggest that CP consists of two components, an "initial depolarization" and a "secondary depolarization," which are usually fused together to give a monophasic potential. Cooling reduced CP frequency and prolonged its duration and caused more cells to show notching. While amplitude and rate of CP initial depolarization had low Q10's, duration and rates of onset and offset of the secondary depolarization had higher Q10's. Thus, the process responsible for secondary depolarization is more sensitive to temperature thant that underlying initial depolarization of the CP.


Author(s):  
Jianan Wang

This paper draws the following conclusions on the nature of time by analyzing the relationship between time and speed, the relationship between time and gravitational field, the gravitational redshift of the photon, and the black-body radiation theorem: Time on an object is proportional to the amount of energy flowing out (or in) per unit time (observer’s time) per unit surface area of the object. When an object radiates energy outward: t'=μB(T) =μσT 4=μnhν/st Where t’ is the time on the object, μ is a constant, B(T) is the radiosity,the total energy radiated from the unit surface area of the object in unit time (observer’s time), σ is the Stefan-Boltzmann constant, T is the absolute temperature, n is the number of the photons radiated, ν is the average frequency of the photons radiated, s is the surface area of the object and t is the time on the observer. When the object radiates energy outward, the higher the energy density of the space (for example the stronger the gravitational field of the space), the smaller the radiosity B(T) of the object in the space, the longer the average wavelength of the light quantum emitted by the object, the slower the time on the object, the longer the life of the system. When the object radiates energy outward, the faster the object moves relative to the ether, the higher the energy density of the local space in which the object is located, the smaller the radiosity B(T) of the object, the longer the average wavelength of the light quantum radiated by the object, the slower the time on the object, and the longer the life of the system. When the object radiates energy outward, the higher the temperature of the object, the greater the object's radiosity B(T), the shorter the average wavelength of the light quantum radiated by the object, the faster the time on the object, and the shorter the life of the system. Applying the above conclusions about the nature of time, the author analyzes the Mpemba effect and the inverse Mpemba effect, and reaches the following conclusion: the Mpemba effect is the time effect produced when heat flows from objects into space, and the "inverse" Mpemba effect is the time effect produced when heat flows from space into objects.


2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Ziqi Lin ◽  
Chenlong Zhang ◽  
Xiaoxin Zhang ◽  
Na Shi ◽  
Yongjian Wen ◽  
...  

Protein kinase C-potentiated inhibitor protein of 17 kDa (CPI-17), a specific inhibitor of myosin light-chain phosphatase (MLCP) regulated by proinflammatory cytokines, is central for calcium sensitisation. We investigated the effects of chaiqin chengqi decoction (CQCQD) on the CPI-17/MLCP pathway in the small intestinal smooth muscle cells (SMCs) and strips (SMS) in an AP model. Necrotising AP was induced in rats by intraperitoneal injections (IPI) of L-ornithine (3.0 g/kg, pH 7.0; hourly × 2) at 1 hour apart; controls received saline. In treatment groups, carbachol (CCh; 60 μg/kg, IPI) or CQCQD (20 g/kg; 2-hourly × 3, intragastric) was administered. The necrotising AP model was associated with systemic inflammation (serum IL-1β and TNF-α) and worsened jejunum histopathology and motility (serum vasoactive intestinal peptide and intestinal fatty acid-binding protein) as the disease progressed. There was decreased intracellular calcium concentration ([Ca2+]i) SMCs. Contractile function of isolated SMCs was reduced and associated with down-regulated expression of key mRNAs and proteins of the CPI-17/MLCP pathway as well as increased IL-1β and TNF-α. CQCQD and CCh significantly reversed these changes and the disease severity. These data suggest that CQCQD can improve intestinal motility by modulating the CPI-17/MLCP pathway in small intestinal smooth muscle during AP.


2002 ◽  
Vol 46 (11-12) ◽  
pp. 217-224 ◽  
Author(s):  
K. Sato ◽  
H. Sakui ◽  
Y. Sakai ◽  
S. Tanaka

Water purification using artificial wetlands and aquatic macrophyte is attracting attention as a purification technology that can create rich ecosystems while imposing a minimal load on the environment. Because an aquatic plant system requires a large surface area, design specifications and maintenance methods that can obtain the optimum purification effect per unit surface area must be established. Large experimental facilities have been constructed beside a polluted river flowing into Lake Kasumigaura and have been used for a three-year experiment using several kinds of aquatic plants. This report summarizes the characteristics and the design load of the aquatic plant system based on this study and results from other aquatic plant facilities.


2001 ◽  
Vol 120 (5) ◽  
pp. A534 ◽  
Author(s):  
Aiping Zhao ◽  
Daniel P. Mulloy ◽  
Joseph F. Urban ◽  
William C. Gause ◽  
Terez Shea-Donohue

1971 ◽  
Vol 69 (1) ◽  
pp. 27-33 ◽  
Author(s):  
N. M. Larin ◽  
P. H. Gallimore

SUMMARYThis paper reports a study carried out to clarify the mechanisms involved in adsorption of influenza A and B viruses on iron oxide. Accordingly, the amounts of virus that are adsorbed from virus suspensions of varying concentrations per unit surface area of magnetic or non-magnetic oxide at fixed temperature and time have been determined. The principles involved are clearly the same as those involved in multiple equilibria during the interaction of particles with a large number of combining sites with different intrinsic affinity. Consequently, the amount of virus that is adsorbed per unit mass of iron oxide depends on the size of the adsorbent area, not on its magnetic property. Owing to a significant difference between the affinities of influenza A and B particles for the binding sites on iron oxide, unit surface area of the adsorbent is invariably capable of adsorbing significantly greater amounts of influenza A than B particles. The practical implications of these findings are that a better understanding of the mechanisms involved in virus adsorption on iron oxide will permit a more efficient separation of virus particles from impurities. The simplicity and the rapidity of the technique and the cheapness of the equipment required suggest that the iron oxide method is of great value for both small- or large-scale viral purification, whether it is used as a single step procedure or as a primary step followed by zonal separation.


Author(s):  
Sezai Alkan ◽  
Taki Karslı ◽  
İsmail Durmuş ◽  
Kemal Karabağ

The aim of this study was to investigated the effects of the egg shape index on egg quality characteristics in Guinea fowl. For this, the eggs were classified in terms of egg shape index, as ≤ 75, < 76 -77 > and ≥ 78. A total of 100 Guinea fowl eggs were evaluated to determine the egg quality traits ( egg weight, eggshell thickness, eggshell surface area, eggshell weight per unit surface area, eggshell ratio, albumen index, albumen ratio, yolk index, yolk ratio, yolk/albumen ratio, haugh unit and egg volume). In this study, eggshell thickness, eggshell weight per unit surface area, eggshell ratio, albumen index, albumen ratio, yolk index, yolk ratio, yolk/albumen ratio and haugh unit were not significantly affected by egg shape index groups. Whereas egg weight, eggshell surface area and egg volume were significantly affected by egg shape index groups. At the same time, there were found significant relationship between the egg shape index and egg quality traits. Egg shape index was found to be an important factor affecting the egg quality characteristics.


1990 ◽  
Vol 14 ◽  
pp. 346
Author(s):  
R.M. MacKay ◽  
M.A.K. Khalil

A physically plausible theory of the 100 kyr climate cycle is proposed. Free oscillations between the mean ocean temperature and the marine ice-margin colatitude are shown to exist without requiring orbital forcing. It is shown that the curvature of the Earth causes two effects: (1) as the marine ice margin grows towards the equator, the net emmision of radiation (solar and terrestrial) per unit surface area increases; and (2) as the poleward extent of the ocean decreases, the net absorption of radiation per unit surface area increases. These radiation balance considerations, included with a realistic meridional transport of energy from the ocean to the marine-ice region and an atmospheric feedback process enhancing the ocean warming, are combined to form two nonlinear differential equations coupling the mean ocean temperature with the marine-ice margin colatitude. Using physically realistic parameters we are able to reproduce the major features of the 100 kyr climate cycle. This can be seen from Figure I which shows the δ18O record as given by Imbrie and others (1984), plotted against the model output. In addition we have found that the parameters used to obtain the general features of the ice-volume record also predict temperature “spikes” (1 to 2 K. above average) of relatively short duration (5 to 10 kyr) in the mean ocean temperature. We find that there is good qualitative agreement between the model's predicted mean ocean temperature and the estimation of summer sea-surface temperature at RC11-120 presented by Martinson and others (1987).


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