Presence Of Contractility Research Articles

Presence of esophageal contractility after achalasia treatment is associated with improved esophageal emptying.

Some achalasia patients exhibit esophageal contractile activity on follow-up after treatment, yet its importance remains unclear. We aimed to identify factors associated with presence of contractility after treatment and to assess its impact on timed barium esophagram (TBE) and clinical outcomes. Patients with type I or II achalasia on baseline high-resolution manometry (HRM) who completed HRM, TBE, and functional lumen imaging probe (FLIP) after treatment were retrospectively identified. Contractility was defined on post-treatment HRM as presence of at least 1 supine swallow with DCI ≥100 mmHg s cm. One hundred twenty-two patients were included (mean age 48 ± 17 years, 50% female). At follow-up evaluation after treatment (54% peroral endoscopic myotomy, 24% pneumatic dilation, 22% laparoscopic Heller myotomy), 61 (50%) patients had contractility on HRM. Patients with contractility (compared to those without) more frequently had type II achalasia (84% vs 57%, p = 0.001) and a post-treatment normal EGJ opening classification on FLIP (69% vs 49%; p < 0.001). In the subgroup of patients with post-treatment integrated relaxation pressure <15 mmHg and normal EGJ opening on FLIP (n = 53), those with contractility had a lower median column height on TBE at 1 min (4 vs 7 cm, p = 0.002) and 5 min (0 vs 5 cm, p = 0.001). In patients with "abnormal" EGJ metrics, patients with contractility showed lower symptom scores (median Eckardt score 2 vs 3, p = 0.03). Occurring more frequently in type II achalasia, and if adequate EGJ opening is achieved after treatment, esophageal contractility may contribute to improved esophageal emptying and improved symptoms in non-spastic achalasia. Preservation of esophageal body muscle could improve outcomes in these patients.

The Predictive Value of Intraoperative Esophageal Functional Luminal Imaging Probe Panometry in Patients With Achalasia Undergoing Peroral Endoscopic Myotomy: A Single-center Experience.

Background/AimsWe evaluated the clinical significance and prognostic power of functional luminal imaging probe (FLIP) panometry in patients with achalasia treated with peroral endoscopic myotomy (POEM), and examined the clinical parameters associated with symptomatic improvement and the presence of contractility (POC) following POEM.MethodsWe reviewed the electronic medical records of patients with achalasia treated with FLIP panometry and POEM at a tertiary teaching hospital in Seoul, Republic of Korea. Follow-up examination was composed of esophageal manometry and questionnaires on symptoms. We analyzed the FLIP data by interpolating using the cubic spline method in MATLAB.ResultsWe retrospectively analyzed 33 men and 35 women (mean age 52 ± 17 years), of whom 14, 39, and 15 patients were diagnosed with achalasia types I, II, and III, respectively. The FLIP panometry diagnoses were reduced esophagogastric junction opening (REO) with a retrograde contractile response (n = 43); REO with an absent contractile response (n = 5); REO with a normal contractile response (n = 11); and a retrograde contractile response (n = 9). Overall, the patients showed improvements in Eckardt scores following POEM from 6.48 ± 2.20 to 1.16 ± 1.15 (P < 0.01). Post-POEM symptomatic improvement was not significantly associated with any of the clinical parameters, including panometry diagnosis. Conversely, post-POEM POC was significantly associated with the presence of repetitive antegrade contractions and achalasia subtypes (both P < 0.01).ConclusionWhile FLIP panometry was not significantly associated with the clinical course of achalasia, FLIP panometry was associated with POC following POEM and may complement manometry in the functional evaluation of esophageal motility disorders.

Multiphase mechanics of capsule formation in tumors.

The presence of a capsule around a tumor is known to be correlated with benign status, and the absence of a capsule often has negative implications for patient prognosis. A mechanical description is presented of the growth of a tumor and the resulting deformations of surrounding normal tissue. A mathematical model of the mechanics is analyzed using physical parameters measured in vivo and in vitro. The model has only three dimensionless parameters, and its results are very robust with respect to parameter variation. We show that the presence of contractility in the surrounding tissue, corresponding to a host defense, can make an existing capsule denser and constrain the tumor better, but cannot be responsible for the observed pressure gradients in encapsulated tumors. Some implications for treatment are discussed.

Studies on hexactinellid sponges. III. The taxonomic status of hexactinellida within the porifera

Recent findings on the structure and physiology of the enigmatic hexactinellid sponges challenge the conventional definition and classification scheme of the Porifera. The gradual acceptance of the choanocyte element as a diagnostic morphological character of the phylum must be revised in the light of the syncytial (acellular) and enucleate condition of the hexactinellid flagellated chambers. The contrasts between the hexactinellids and all other sponges are reviewed and considered sufficient to require recognition of a primary subdivision at the subphylum level. The major differences include, respectively, syncytial (or symplastic) as against cellular organization, acellular as against cellular (pinacocytic) epithelia, thin as against abundant mesohyle matrix, absence as against presence of contractility, and presence as against absence of a relatively rapid conduction system. The new findings support Reid’s 1958 allocation of classes in his subdivision of the phylum, but the names that he employed, Nuda and Gelatinosa, are considered inappropriate for present use because of the hypothetical basis of their origin and of the lack of descriptive value of the names in the present context (R. E. H. Reid,Palaeontogr. Soc.[Monogr.] I ll, 1-46 (1958)). Two new subphyla are proposed and defined, the Symplasma to include the single class Hexactinellida, and the Cellularia to include all other extant sponges of the classes Calcarea, Demospongiae and Sclerospongiae.

Contractility and its control in peritrich ciliates.

SYNOPSISA review of the recent literature on the structure and physico‐chemical properties of the myoneme and its specialization, the spasmoneme, of peritrich ciliates was made. Myonemes are composed of tightly packed bundles of 3–5 nm microfibrils which parallel, more or less, the long axis of the bundle and are of indefinite length. The presence of contractility in these ciliates is correlated with the presence of myonemes. Associated with the microfibrils is a system of membrane‐bound tubules and saccules continuous with the endoplasmic reticulum (ER). This system is known to accumulate calcium. Myonemes differ from muscles in their structure, solubility properties, birefringence pattern, and in the time during the contraction‐relaxation cycle at which they require energy. They may be related more closely to the cytochalasin B‐sensitive microfibrils of higher organisms than to muscles. Contraction of extracted stalks can be induced solely by raising the calcium ion concentration above a certain threshold. Thus the calcium‐accumulating myoneme‐associated ER would appear to play an important role in the control of myoneme contractility. A specialization at the interface between the myoneme and the ER membranes is described as it appears in Vorticella and Opercularia. This structure, called a linkage complex, is found both in the body myonemes and the spasmoneme and links the membranes of the ER to the microfibrils. It also has microfilaments that pass from the ER‐myoneme interface to the surface membranes. The uniqueness of this structure and its location suggests that it may play a role in controlling the movements of calcium between the ER and myoneme and also in transmission of messages from the pellicular membranes, possibly the alveolar sacs, to the ER.