Regional differences in potassium content of smooth muscle from opossum esophagus.

1978 ◽  
Vol 235 (6) ◽  
pp. E709
Author(s):  
K Schulze ◽  
J J Hajjar ◽  
J Christensen

Strips from the proximal part of the smooth muscle segment of opossum esophagus have a significantly higher potassium content (50 +/- 3 meq/kg) than those from the distal part (38 +/- 3 meq/kg). There are no significant differences between the two regions in content of sodium (65 +/- 4 meq/kg in proximal, 71 +/- 3 meq/kg in distal) or chloride (48 +/- 10 meq/kg in proximal, 42 +/- 5 meq/ kg in distal). The mean [14C]inulin uptake is 240 +/- 10 ml/kg in both proximal and distal strips. [14C]polyethylene glycol uptake is smaller and [14C]sucrose and [14C]mannitol uptake in both areas are larger than that of inulin. Intracellular potassium concentration (based on the inulin uptake as an estimate of the extracellular space volume) is significantly higher proximally (71 +/- 3 mM) than distally (52 +/- mM). Ouabain, 10(-4) M, increases the intracellular concentration of sodium and decreases the intracellular concentration of potassium in both the proximal and distal segment. The efflux of 86Rb, measured by a washout technique, is higher in the distal than in the proximal smooth muscle segment. A difference in membrane permeability to rubidium and hence, potassium between proximal and distal smooth muscle segments may account in part for the different intracellular potassium concentrations.

2021 ◽  
Vol 34 (Supplement_1) ◽  
Author(s):  
Dmitry Bordin ◽  
Elen Valitova ◽  
Gulsara Baymakanova ◽  
Stanislav Krasovskiy ◽  
Olga Berezina

Abstract   The presence of gastroesophageal reflux in patients after lung transplantation rises the risk of posttransplantant complications. The aim of our study was to evaluate the severity of gastroesophageal reflux (GER) in patients with cystic fibrosis before lung transplantation. Methods 14 patients with cystic fibrosis, who refferred to our Centre, were included in this study, mean age 28,86 ± 2,5 (6 males and 8 females). The diagnosis of cystic fibrosis was established at the age of 1–5 y.o. according to clinic, sweet test and genetic tests. All patients were performed upper endoscopy, X-ray, esophageal manometry and 24 h impedance monitoring. PPI treatment was excluded for 7 days before monitoring. Pathologic GER was established when total number of refluxes in distal esophagus was more than 75, the total number of refluxes in proximal esophagus was more than 20% of those in the distal part. Results According to endoscopy, none of patients had erosions of the esophagus. Five patients had ineffective motility and one—diffuse esophageal spazm. 56% of patients had pathologic number of refluxes in distal esophagus. 80% subjects had pathologic refluxes in proximal esophagus. The mean number of total refluxes in distal part was 54,93 ± 5,7, in proximal part—27,64 ± 2,6 (it is 40% of those in distal part). The distribution of acid and non-acid refluxes in patients with pathologic refluxes was 2:1. We didn’t reveal any correlation between number of refluxes, ineffective motility and gastric emptying. Conclusion despite normal upper endoscopy, 56% of patients with cystic fibrosis have pathologic gastroesophageal reflux. Besides, the study showed high propagation of GER to proximal esophagus in 80% of subjects, which may play role in posttransplantation period.


1977 ◽  
Vol 53 (3) ◽  
pp. 289-296 ◽  
Author(s):  
C. M. Mackie ◽  
E. R. Simpson ◽  
M. S. R. Mee ◽  
S. A. S. Tait ◽  
J. F. Tait

1. A method involving centrifugation through phthalate ester oils is described for the rapid separation of isolated cells from suspending medium. Intracellular potassium concentrations and intracellular water space values for isolated adrenal zona glomerulosa and zona fasciculata cells are given. 2. The effects of angiotensin II and a high external potassium concentration (8·4 mmol/l) on intracellular potassium contents, intracellular water spaces and hence intracellular potassium concentrations of purified glomerulosa cells have been investigated. Corticosterone secretion was also measured. Previously reported results showing a significant increase in potassium content with high external potassium were confirmed. However, angiotensin II slightly, but significantly, decreased potassium content. No significant change in intracellular water space or intracellular potassium concentration was observed with either stimulus. 3. Both stimuli significantly increased corticosterone production. There was no correlation between the percentage increase in potassium content or concentration and the percentage increase in steroid output after stimulation with high external potassium. 4. It is concluded that angiotensin II does not stimulate steroidogenesis in adrenal glomerulosa cells by raising the intracellular potassium concentration. The small, but statistically insignificant, increase caused by high-potassium medium is unlikely to be causally linked to steroidogenesis.


1977 ◽  
Vol 232 (3) ◽  
pp. E270
Author(s):  
K Schulze ◽  
J L Conklin ◽  
J Christensen

Sodium and potassium content were determined in the smooth muscle segment of the opossum esophagus. Extracellular space measurements were also made using inulin and mannitol as markers. The muscle also made using inulin and mannitol as markers. The muscle was sampled at five sites spaced equally along the esophageal segment. On site in the stomach was also examined. The mean tissue sodium content was 36.6 +/- 10.7 meg/kg, and the mean tissue sodium content was 83.5 +/- 2.9 meg/kg wet wt. The mean inulin space was 184 +/- 34 ml/kg, and the mean mannitol space was 249 +/- 20 ml wet wt. The tissue potassium content was found to decline from 48.4 /- 10.1 meg/kg at the proximal site to 23.6 +/- 8.0 meg k/g at the distal site. The slope of electrolyte values from sites 1 through 5 was significant for both potassium and sodium. Extracellular space volume did not differ significantly from one end of the smooth muscle segment to the other.


Vision ◽  
2022 ◽  
Vol 6 (1) ◽  
pp. 4
Author(s):  
Vinod Kumar ◽  
Kamal Abdulmuhsen Abu Zaalan ◽  
Andrey Igorevich Bezzabotnov ◽  
Galina Nikolaevna Dushina ◽  
Ahmad Saleh Soliman Shradqa ◽  
...  

The deep sclerectomy technique was modified to enhance aqueous humor (AH) outflow via the non-trabecular pathway. A pilot study was carried out to assess its safety and effectiveness. Thirty-eight patients were under observation. After superficial scleral flap (4 × 4 mm), deep scleral layers were divided into three parts by three parallel-to-limbus incisions. Deep sclerectomy without creating a window in the Descemetes’ membrane was carried out in the distal part. A collagen implant was placed under the sclera of the remaining two parts with one end in the intrascleral pool. The third proximal part was excised to expose the uvea and implant. A Nd:YAG laser trabeculotomy at the surgery site was made on postoperative days 7–10. Outcome measures were IOP change, use of hypotensive medication(s), complications, and the need for a second surgery. At six months, the mean IOP decreased from 29.1 ± 9.2 mm Hg to 14.0 ± 4.3 mm Hg (p = 1.4 × 10−9); hypotensive medication use reduced from 2.9 ± 0.9 to 0.6 ± 1.0 (p = 1.3 × 10−10); complete success was achieved in 68.4% of cases and partial success was achieved in 31.6% of cases. Intraoperative and postoperative complications were rare and manageable. The OCT of the surgery site revealed the absence of bleb in all cases. Lymphatic vessels with characteristic bicuspid valves in their lumen were detected in conjunctiva near the operation site and over it in 32 patients. IOP decrease in the proposed technique was achieved by activation of the uveolymphatic route of AH outflow.


1975 ◽  
Vol 49 (1) ◽  
pp. 1-12
Author(s):  
F. A. O. Mendelsohn ◽  
R. L. Warren

1. A technique is described for the measurement of potassium and water spaces in less than 1 μ1 of packed cells. 2. The total potassium content of cell pellets is measured in a perchloric and nitric acid extract by flame spectrophotometry. The potassium in trapped medium is estimated from the distribution space of hydroxy[14C]methylinulin and subtracted from the total potassium content to give intracellular potassium content. Corticosterone output was measured by radioimmunoassay. 3. The simultaneous measurement of total water from the [3H]water space allows calculation of the intracellular water space. 4. Values obtained for intracellular potassium content, intracellular water space and calculated intracellular potassium concentration are presented for different preparations of isolated adrenal cortical cells.


Author(s):  
Maria Anna Pabst

In addition to the compound eyes, honeybees have three dorsal ocelli on the vertex of the head. Each ocellus has about 800 elongated photoreceptor cells. They are paired and the distal segment of each pair bears densely packed microvilli forming together a platelike fused rhabdom. Beneath a common cuticular lens a single layer of corneagenous cells is present.Ultrastructural studies were made of the retina of praepupae, different pupal stages and adult worker bees by thin sections and freeze-etch preparations. In praepupae the ocellar anlage consists of a conical group of epidermal cells that differentiate to photoreceptor cells, glial cells and corneagenous cells. Some photoreceptor cells are already paired and show disarrayed microvilli with circularly ordered filaments inside. In ocelli of 2-day-old pupae, when a retinogenous and a lentinogenous cell layer can be clearly distinguished, cell membranes of the distal part of two photoreceptor cells begin to interdigitate with each other and so start to form the definitive microvilli. At the beginning the microvilli often occupy the whole width of the developing rhabdom (Fig. 1).


2003 ◽  
Vol 42 (03) ◽  
pp. 90-93 ◽  
Author(s):  
N. Döbert ◽  
O. Rieker ◽  
W. Kneist ◽  
St. Mose ◽  
A. Teising ◽  
...  

SummaryAim: Evaluation of the influence of histopathologic sub-types and grading of primaries of oesophageal cancer, relative to their size and location, on the uptake of 18F-deoxyglucose (FDG) as measured by positron emission tomography (PET). Methods: 50 consecutive patients were evaluated. There were four drop-outs due to previous surgical and/or chemotherapeutical treatments and thus in 46 patients (28 squamous cell carcinomas and 18 adenocarcinomas) a pretherapeutic PET evalution of the primary including a standard uptake value (SUV) was obtained. In 42 cases data on tumour grading were available also. Results: Squamous cell carcinomas (SCC) were in 7/13/8 cases located in the proximal, medial and distal part of the oesophagus, respectively the grading was Gx in 3, G 2 in 12, G2-3 in 7, and G3 in 6 cases. The SUVmax showed a mean of 6.5 ± 2.8 (range 1.7-13.5). Adenocarcinomas (ACA) were located in the medial oesophagus in two cases and otherwise in its distal parts. Grading was Gx in one, G2 in 4, G2-3 in 3, G3 in 3, G3-4 in 3, and G4 in one case. The mean SUVmax was 5.2 ± 3.2 (range 1-13.6) and this was not significantly different from the SCC. Concerning the tumour grading there was a slight, statistically not relevant trend towards higher SUVmax in more dedifferentiated cancer. Discussion: SCC and ACA of the oesophagus show no relevant differences in the FDG-uptake. While there was a significant variability of tumour uptake in the overall study group, a correlation of SUV and tumour grading was not found.


2021 ◽  
Vol 114 (1) ◽  
Author(s):  
Jérémy Ragusa ◽  
Lina Maria Ospina-Ostios ◽  
Pascal Kindler ◽  
Mario Sartori

AbstractThe Voirons Flysch (Caron in Eclogae Geologicae Helvetiae 69:297–308, 1976), is a flysch sequence aggregated into the sedimentary accretionary prism of the Chablais and Swiss Prealps. Its palaeogeographic location is still debated (South Piemont or Valais realm). We herein present a stratigraphic revision of the westernmost unit of the former Gurnigel Nappe sensu Caron (Eclogae Geologicae Helvetiae 69:297–308, 1976): the Voirons Flysch. This flysch is subdivided into three lithostratigraphic units at the formation level (the Voirons Sandstone, the Vouan Conglomerate, the Boëge Marl), with an additional unit (Bruant Sandstone) of uncertain attribution, ranging from the early Eocene to probably the late Eocene. We further propose a new model of the depositional setting of the deep-sea of the Voirons Flysch based on palaeocurrent directions, the overall geometry and sedimentary features. This model depicts an eastward deflected deep-sea fan. The stratigraphic record of the proximal part of this fan is fairly complete in the Voirons area, whereas its most distal part is only represented by one small exposure of thinly bedded sandstones in the Fenalet quarry. The stratigraphic evolution of the Voirons Flysch shows two major disruptions of the detrital sedimentation at the transition between Voirons Sandstone—Vouan Conglomerate and Vouan Conglomerate—Boëge Marl. The cause of these disturbances has to be constrained in the framework of the palaeogeographic location of the Voirons Flysch.


1975 ◽  
Vol 67 (1) ◽  
pp. 93-104 ◽  
Author(s):  
T D Pollard

Electron micrographs of negatively stained synthetic myosin filaments reveal that surface projections, believed to be the heads of the constituent myosin molecules, can exist in two configurations. Some filaments have the projections disposed close to the filament backbone. Other filaments have all of their projections widely spread, tethered to the backbone by slender threads. Filaments formed from the myosins of skeletal muscle, smooth muscle, and platelets each have distinctive features, particularly their lengths. Soluble mixtures of skeletal muscle myosin with either smooth muscle myosin or platelet myosin were dialyzed against 0.1 M KC1 at pH 7 to determine whether the simultaneous presence of two types of myosin would influence the properties of the filaments formed. In every case, a single population of filaments formed from the mixtures. The resulting filaments are thought to be copolymers of the two types of myosin, for several reasons: (a) their length-frequency distribution is unimodal and differs from that predicted for a simple mixture of two types of myosin filaments; (b) their mean length is intermediate between the mean lengths of the filaments formed separately from the two myosins in the mixture; (c) each of the filaments has structural features characteristic of both of the myosins in the mixture; and (d) their size and shape are determined by the proportion of the two myosins in the mixture.


2021 ◽  
pp. postgradmedj-2021-141244
Author(s):  
Gizem Issin ◽  
Fatih Demir ◽  
Hasan Aktug Simsek ◽  
Diren Vuslat Cagatay ◽  
Mahir Tayfur ◽  
...  

Background and aimsAppendiceal neoplasms are uncommon entities that are usually determined incidentally during the histopathological examination. Different techniques used for the macroscopic sampling of appendectomy material may affect the determinating neoplasms.Materials and methodsH&E-stained slides of 1280 cases who underwent appendectomy between 2013 and 2018 were reviewed retrospectively for histopathological features.ResultsNeoplasms were determined in 28 cases (3.09%); 1 lesion was observed in the proximal part of the appendix, 1 covering the entire length from proximal to distal and 26 in the distal part. In the 26 cases that observed in the distal part, the lesion was seen on both sides of the longitudinal section of the distal appendix in 20 cases, while it was seen on only one distal longitudinal section in the remaining 6 cases.ConclusionThe vast majority of appendiceal neoplasms are seen in the distal part of the appendix, and, in some cases, neoplasms might be seen on only one side of the distal section. Sampling only one-half of the distal part of the appendix, where tumours are most often observed, could result in some neoplasms being missed. Therefore, sampling the whole distal part would be more beneficial to determine small diameter tumours that do not create macroscopic findings.


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