Changes in the distribution of Hymenolepis diminuta (Cestoda: Cyclophyllidea) within the rat intestine during prepatent development

1970 ◽  
Vol 48 (4) ◽  
pp. 761-769 ◽  
Author(s):  
Christine E. Cannon ◽  
D. F. Mettrick
Keyword(s):  
Small Intestine ◽  
Weight Distribution ◽  
Attachment Site ◽  
Pyloric Sphincter ◽  
Hymenolepis Diminuta ◽  
Rat Intestine ◽  
Intestinal Length ◽  
Attachment Sites ◽  
The Mean

The changes in the distribution of Hymenolepis diminuta within the rat intestine have been followed over the period 3 to 16 days postinfection using rats, each infected with 10 cysticercoids of H. diminuta, fed ad libitum on Purina Rat Chow.The parameters investigated were distribution of scolex attachment sites in the intestine, and distribution of parasite biomass in the intestine based on strobila length, ex vivo weight distribution, and in vivo weight distribution. Both the scoleces and biomass of 3- and 5-day-old worms are concentrated in the second quarter of the intestine. The mean scolex attachment point for 5-day-old worms was 39% of the total intestinal length behind the pyloric sphincter. Between days 5 and 7 there was a marked anterior migration of the young worms, so that at 7 days the mean scolex attachment site was 15% of the total intestinal length behind the stomach. Over the same period of time the mean in vivo weight distribution moved forward from a point 44% behind the pyloric sphincter to one only 23% along the intestine. After 7 days there was a gradual posteriad spreading of the scolex attachment sites and of the parasite biomass. Hymenolepis diminuta can attach itself anywhere in the anterior 75% of the intestine, including in front of the opening of the bile duct: no worms were found in the small intestine extending back into the caecum.The pattern of migration and the changes in worm distribution in the intestine suggest that H. diminuta selects an appropriate, but changing position, on one or more of the gradients that have been demonstrated or postulated along the length of the small intestine.It is also suggested that the long-term migration during prepatent development is interrelated, but distinct from the daily migrational movements that H. diminuta undergoes within the small intestine.

Variation in the size and position of Hymenolepis diminuta (Cestoda: Cyclophyllidea) within the rat intestine

1969 ◽  
Vol 47 (6) ◽  
pp. 1091-1101 ◽  
Author(s):  
D. F. Mettrick ◽  
Lorna C. Dunkley
Keyword(s):  
Body Weight ◽  
Experimental Design ◽  
Frequency Distribution ◽  
Dry Weight ◽  
Pyloric Sphincter ◽  
Hymenolepis Diminuta ◽  
Female Rats ◽  
Rat Intestine ◽  
Male And Female ◽  
Male And Female Rats

Data on the dry weight of 410 worms from both male and female rats is shown not to differ significantly from the normal (Gaussian) frequency distribution. This finding justified the use of statistics based on this function.Host body weight is shown to have a highly significant (P < 0.01) effect upon worm dry weight. The heavier the rat, the smaller the worms. An experimental design taking rat body weight into consideration is shown to be up to 36% more efficient in demonstrating differences between groups than one that ignores this source of variation. The point of scolex attachment behind the pyloric sphincter also has a significant effect (P < 0.05) upon worm dry weight. The nearer the scolex is to the stomach, the smaller the worm.The distribution of worm biomass in the intestine does not follow a normal (Gaussian) frequency, but is both asymmetrical (P < 0.001) and flattened (P < 0.001). Over 50% of the parasite biomass lies within the second quarter of the intestine. The distribution of the median points of worm strobilae in the rat intestine is also asymmetrical (P < 0.01) with a peak in the zone which represents a distance of 30–35% from the stomach.The migration of H. diminuta within the rat intestine results in the greater part of the parasite body lying in the second quarter of the intestine. The median points of the strobilae are concentrated at the junction of the first and second quarters of the intestine. This region of the rat intestine appears to offer the optimum site for the growth of H. diminuta.

Apolipoprotein A-IV synthesis in rat intestine: regulation by dietary triglyceride

1987 ◽  
Vol 252 (5) ◽  
pp. G662-G666 ◽  
Author(s):  
T. F. Apfelbaum ◽  
N. O. Davidson ◽  
R. M. Glickman
Keyword(s):  
Protein Synthesis ◽  
Small Intestine ◽  
Total Protein ◽  
Mrna Levels ◽  
Rat Small Intestine ◽  
Rat Intestine ◽  
Apolipoprotein A ◽  
Rat Enterocytes

Apolipoprotein A-IV (apoA-IV) synthesis rates were measured in vivo in rat enterocytes by immunoprecipitation after administration of [3H]leucine into in situ loops of jejunum and ileum. Basal apoA-IV synthesis rates (percent total protein synthesis) were significantly higher in jejunal enterocytes (2.05 +/- 0.54%) compared with ileal enterocytes (0.48 +/- 0.32%) from the same fasted animals. After an acute triglyceride bolus, significant and sustained elevations of apoA-IV synthesis rates were seen in both jejunal and ileal enterocytes with maximal effects noted at 4-6 h. Animals fed diets containing 30% wt/wt triglyceride as saturated (SF) or polyunsaturated (UF) fats for 6 wk had similarly increased rates of apoA-IV synthesis in jejunal enterocytes with both SF (3.73 +/- 0.83%) and UF (3.33 +/- 0.64%) but no change in ileal enterocytes. By contrast, animals consuming a fat-free diet for 3 wk had jejunal apoA-IV synthesis rates indistinguishable from basal values (2.40 +/- 0.45%). Translatable intestinal mRNA levels for pre-apoA-IV after triglyceride increased in parallel to synthesis rates with a 50% increase in jejunum and a 350% increase in ileum observed at 4-6 h. These results suggest that apoA-IV synthesis by rat small intestine increases in response to acute and chronic dietary triglyceride, is maintained in the absence of dietary triglyceride, and may be under pretranslational control.

scholarly journals Reconsidering Reciprocal Length Patterns of the Anteromedial and Posterolateral Bundles of the Anterior Cruciate Ligament During In Vivo Gait

2020 ◽  
Vol 48 (8) ◽  
pp. 1893-1899 ◽  
Author(s):  
Zoë A. Englander ◽  
Jocelyn R. Wittstein ◽  
Adam P. Goode ◽  
William E. Garrett ◽  
Louis E. DeFrate
Keyword(s):  
Anterior Cruciate Ligament ◽  
Knee Joint ◽  
Cruciate Ligament ◽  
Functional Anatomy ◽  
Attachment Site ◽  
Attachment Sites ◽  
Biplanar Radiographs ◽  
Anterior Cruciate ◽  
The Right

Background: Some cadaveric studies have indicated that the anterior cruciate ligament (ACL) consists of anteromedial and posterolateral bundles that display reciprocal function with regard to knee flexion. However, several in vivo imaging studies have suggested that these bundles elongate in parallel with regard to flexion. Furthermore, the most appropriate description of the functional anatomy of the ACL is still debated, with the ACL being described as consisting of 2 or 3 bundles or as a continuum of fibers. Hypothesis: As long as their origination and termination locations are defined within the ACL attachment site footprints, ACL bundles elongate in parallel with knee extension during gait. Study Design: Descriptive laboratory study. Methods: High-speed biplanar radiographs of the right knee joint were obtained during gait in 6 healthy male participants (mean ± SD: body mass index, 25.5 ± 1.2 kg/m2; age, 29.2 ± 3.8 years) with no history of lower extremity injury or surgery. Three-dimensional models of the right femur, tibia, and ACL attachment sites were created from magnetic resonance images. The bone models were registered to the biplanar radiographs, thereby reproducing the in vivo positions of the knee joint. For each knee position, the distances between the centroids of the ACL attachment sites were used to represent ACL length. The lengths of 1000 virtual bundles were measured for each participant by randomly sampling locations on the attachment site surfaces and measuring the distances between each pair of locations. Spearman rho rank correlations were performed between the virtual bundle lengths and ACL length. Results: The virtual bundle lengths were highly correlated with the length of the ACL, defined as the distance between the centroids of the attachment sites (rho = 0.91 ± 0.1, across participants; P < 5 × 10-5). The lengths of the bundles that originated and terminated in the anterior and medial aspects of the ACL were positively correlated (rho = 0.81 ± 0.1; P < 5 × 10-5) with the lengths of the bundles that originated and terminated in the posterior and lateral aspects of the ACL. Conclusion: As long as their origination and termination points are specified within the footprint of the attachment sites, ACL bundles elongate in parallel as the knee is extended. Clinical Relevance: These data elucidate ACL functional anatomy and may help guide ACL reconstruction techniques.

Components of Glucose Transport in the Host–Parasite System, Hymenolepis diminuta (Cestoda) and the Rat Intestine

1974 ◽  
Vol 52 (2) ◽  
pp. 183-197 ◽  
Author(s):  
R. B. Podesta ◽  
D. F. Mettrick
Keyword(s):  
Glucose Transport ◽  
Fluid Transport ◽  
Glucose Absorption ◽  
Hymenolepis Diminuta ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Solvent Drag ◽  
Rat Intestine ◽  
Hydrogen Ion Concentration

Glucose and fluid transport by the rat intestine and by the tapeworm Hymenolepis diminuta has been studied in vivo, using closed loops of the entire small intestine. The effect of pH, glucose concentration, and the presence of sodium on solute and solvent absorption has been determined in both host and parasite. The effect of the worms on intestinal absorption by the rat has also been evaluated. Three components of the glucose transport system, namely active transport, diffusion, and solvent drag, were determined by means of a model transport equation.Saturation kinetics for glucose absorption did not occur and the absence of sodium in the luminal fluid, while not affecting glucose absorption, markedly reduced fluid absorption by both the intestine and the worms. Lowering the pH of luminal fluids significantly reduced glucose transport by the intestine but increased absorption of fluid and glucose by H. diminuta. Irrespective of pH, fluid and glucose absorption were significantly reduced in the parasitized intestine.Active transport of glucose by normal or parasitized intestine and by H. diminuta was unaffected by the concentration of glucose in the lumen, or by changes in pH. The solvent drag and diffusion components of glucose transport were reduced by increasing the hydrogen ion concentration in uninfected and parasitized intestines. The solvent drag component of glucose absorption by the tapeworms was increased with increasing hydrogen ion concentration.The results are discussed in terms of the current hypotheses on the mechanism of glucose transport, sodium dependency, and the effect of hydrogen ions on transport mechanisms.

In Vitro Absorption of Radioiron by Everted Pouches of Rat Intestine

1958 ◽  
Vol 194 (2) ◽  
pp. 319-326 ◽  
Author(s):  
Elmer B. Brown ◽  
Bertram W. Justus
Keyword(s):  
Small Intestine ◽  
Ferrous Iron ◽  
Ferric Iron ◽  
Metabolic Inhibitors ◽  
Passive Transport ◽  
Rat Intestine ◽  
Intestinal Tissue

Everted pouches of rat intestine prepared by the technique of Wilson and associates were used to measure absorption of radioiron. Iron was taken up equally well in vitro by all segments of the rat's small intestine; but when the iron was given orally in vivo, a distinct gradient, highest in the duodenum and progressively smaller in the distal segments was demonstrated. There was little transfer into the inner serosal pouch. Transfer of iron in this preparation was by a process of passive transport. It was not appreciably affected by changes in pH, various metabolic inhibitors, buffer systems, or added substrates. Ferrous iron was significantly better taken up by the intestinal tissue, but transfer into the inner pouch fluid was greater with ferric iron.

Incorporation of a Poly-ε-Caprolactone Scaffold in a ;Circular Stapled End-To-End Small Intestine Anastomosis Does Not Have Any Adverse Effects Within 30 days: A Study in Piglets

2021 ◽  
pp. 155335062199929
Author(s):  
Nicolai S. Schiellerup ◽  
Joakim Wismann ◽  
Gunvor I. Madsen ◽  
Dang Q S. Le ◽  
Niels Qvist ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Small Intestine ◽  
Contrast Study ◽  
Stricture Formation ◽  
Significant Difference ◽  
The Mean ◽  
End To End ◽  
Observation Period ◽  
Made In

Background . Incorporation of a poly-ε-caprolactone (PCL) scaffold in circular stapled anastomoses has been shown to increase the anastomotic tensile strength on postoperative day (POD) 5 in a pig model. The aim of this study was to investigate the effects of incorporation of a PCL scaffold in a circular stapled end-to-end small intestine anastomosis, with stricture formation and anastomotic histology as primary outcomes in a 30-day observation period. Methods . A total of 15 piglets were included. In each piglet, three circular stapled end-to-end anastomoses were made in the small intestines. Two were interventional and one was a control. On POD 10, 20, or 30, the anastomoses were subjected to in vivo intraluminal contrast study, and the index for anastomotic lumen was calculated. The anastomotic segment was resected and subjected to a tensile strength test and histological examination. Results . At POD 10, the mean ± SD value for anastomotic index was .749 ± .065 in control anastomoses and .637 ± .051 in interventional anastomosis ( P = .0046), at POD 20, .541 ± .150 and .724 ± .07 ( P = .051), and at POD 30, .645 ± .103 and .686 ± .057 ( P = .341), respectively. No significant difference was observed in maximum tensile strength and histology at POD 30. Conclusions . The incorporation of a PCL scaffold in a circular stapled end-to-end small intestine anastomosis does not increase the risk of stricture or impair wound healing after 30 days.

Behavioural adaptation of the tapewormHymenolepis diminutato its environment

Parasitology ◽  
1992 ◽  
Vol 104 (2) ◽  
pp. 331-336 ◽  
Author(s):  
M. V. K. Sukhdeo ◽  
M. S. Kerr
Keyword(s):  
Nervous System ◽  
Small Intestine ◽  
Hymenolepis Diminuta ◽  
Locomotory Activity ◽  
Behavioural Adaptation ◽  
Cerebral Ganglia ◽  
The Central Nervous System ◽  
Anterior Segments

SUMMARYHymenolepis diminutamigrates up the small intestine in response to feeding the host 1 g of glucose. Locomotion during migration may result from fixed patterns of retrograde peristaltic-like waves in the strobila of the tapeworm which propel the organism against the normal expulsive forces in the small intestine. The peristaltic-like locomotory waves occur in a gradient along the strobila with a frequency of 24·9±0·9 cycles/min in the anterior segments of the worm, decreasing linearly to 6·6±1·4 cycles/min in the posterior segments of the worm. Chemical signals, isolated from the small intestine of fed hosts, which stimulate migration behaviourin vivodo not alter the behaviour of the scolex or strobilain vitro. Removal of the scolex containing the cerebral ganglia does not alter the frequency or pattern of locomotory activity in the strobila. After the worm is cut into pieces, each region generates the pattern of locomotory activity that is appropriate for that region. These data suggest that the peripheral nervous system, and not the central nervous system, is responsible for the coordination of the fixed patterns of locomotory activity in these tapeworms.

scholarly journals Effects of short-term insulin deficiency on lipogenesis and cholesterol synthesis in rat small intestine and liver in vivo

1985 ◽  
Vol 231 (1) ◽  
pp. 221-223 ◽  
Author(s):  
D H Williamson ◽  
V Ilic ◽  
J Hughes
Keyword(s):  
Small Intestine ◽  
Cholesterol Synthesis ◽  
Physiological Significance ◽  
Oral Glucose ◽  
Rat Small Intestine ◽  
Insulin Deficiency ◽  
Rat Intestine ◽  
Short Term ◽  
Glucose Loading

The rate of lipogenesis in rat intestine increased on oral glucose loading and decreased after induction of acute insulin deficiency with streptozotocin. The latter effects could be partially reversed by administration of insulin. Parallel changes in the rate of lipogenesis were found in liver. In contrast, insulin deficiency did not alter the rate of cholesterol synthesis in intestine, but decreased it in liver. The physiological significance of the regulation of intestinal lipogenesis by insulin is discussed.

scholarly journals Synthesis, characterization, and pharmacological evaluation of some metal complexes of quercetin as P-gp inhibitors

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Kirankumar Shastrala ◽  
Sirisha Kalam ◽  
Kumaraswamy Damerakonda ◽  
Sharvana Bhava Bandaru Sheshagiri ◽  
Hitesh Kumar ◽  
...  
Keyword(s):  
Small Intestine ◽  
Metal Complexes ◽  
Mobile Phase ◽  
Hplc Method ◽  
Rat Intestine ◽  
Apparent Permeability ◽  
Rp Hplc ◽  
The Mean ◽  
Pre Treatment

Abstract Background Six different metal complexes of quercetin (Cu, Zn, Co, Vd, Mo, Ni) were synthesized, purified, and characterized by their physical and spectral (UV, IR) data. They were evaluated for their P-gp (permeability glycoprotein) inhibitory activity by in vitro everted sac method in rats. The apparent permeability of atorvastatin (P-gp substrate) from everted sac of the rat intestine was determined in control, standard (verapamil), and groups treated with quercetin-metal complexes. The drug contents were analyzed by validated RP-HPLC method using a mixture of acetonitrile and water (60:40 v/v) adjusted to pH 2.8 with phosphate buffer as mobile phase. Results In vitro studies revealed that the apparent permeability of atorvastatin (P-gp substrate) across the small intestine is much affected by the treatment with Cu/Co/Ni complexes of quercetin. The mean ± SD and apparent permeability of atorvastatin decreased after pre-treatment with these metal complexes. Conclusions The quercetin Cu/Co/Ni complexes could inhibit P-gp and increase the atorvastatin absorption. Hence, they could be considered P-gp inhibitors.

Effects of NO-Donors on Thrombus Formation and Microcirculation in Cerebral Vessels of the Rat

1996 ◽  
Vol 76 (01) ◽  
pp. 111-117 ◽  
Author(s):  
Yasuto Sasaki ◽  
Junji Seki ◽  
John C Giddings ◽  
Junichiro Yamamoto
Keyword(s):  
Blood Flow ◽  
Thrombus Formation ◽  
Dependent Manner ◽  
Red Cell ◽  
Cell Velocity ◽  
Red Cell Velocity ◽  
The Mean ◽  
Wall Shear ◽  
Dose Dependent

SummarySodium nitroprusside (SNP) and 3-morpholinosydnonimine (SIN-1), are known to liberate nitric oxide (NO). In this study the effects of SNP and SIN-1 on thrombus formation in rat cerebral arterioles and venules in vivo were assessed using a helium-neon (He-Ne) laser. SNP infused at doses from 10 Μg/kg/h significantly inhibited thrombus formation in a dose dependent manner. This inhibition of thrombus formation was suppressed by methylene blue. SIN-1 at a dose of 100 Μg/kg/h also demonstrated a significant antithrombotic effect. Moreover, treatment with SNP increased vessel diameter in a dose dependent manner and enhanced the mean red cell velocity measured with a fiber-optic laser-Doppler anemometer microscope (FLDAM). Blood flow, calculated from the mean red cell velocity and vessel diameters was increased significantly during infusion. In contrast, mean wall shear rates in the arterioles and venules were not changed by SNP infusion. The results indicated that SNP and SIN-1 possessed potent antithrombotic activities, whilst SNP increased cerebral blood flow without changing wall shear rate. The findings suggest that the NO released by SNP and SIN-1 may be beneficial for the treatment and protection of cerebral infarction

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