scholarly journals THE ANALYSIS OF NEUROMUSCULAR MECHANISMS IN CHITON

1920 ◽  
Vol 2 (6) ◽  
pp. 627-634 ◽  
Author(s):  
W. J. Crozier

1. The degree of curvature of the body and of the girdle of a Chiton is determined by the activity of antagonistic muscle groups. At a certain, early stage in the strychninization of a Chiton the reciprocal inhibition involved in the natural use of these muscle groups is reversed, such that extensor muscles, rather than, as normally, flexor muscles, contract as the result of stimulation. This condition involves a reversal, under strychnine, of the normally positive stereotropism of the foot, and of the usual response of the mollusk to an increased illumination of its ventral surface. Strychnine reversal of this character is not a matter of the relative strength of the opposed muscle groups, for the flexor muscles are the more powerful and are the ones always shortened in tetanic contraction. 2. Nicotine, in contrast to strychnine, primarily induces contraction of flexor muscles. Its effects, moreover, are in a degree selective, being notably exerted on "cerebral" nervous structures. Curare is devoid of characteristic action on the neuromuscular responses of Chiton. 3. The chemical organization of the neuromuscular organs of Chiton, as far as revealed by these tests, corresponds to a more simple condition than is inferred for gastropods. In particular, the behavior with respect to curare resembles more that of the neuromuscular apparatus of flatworms.

Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1532
Author(s):  
Jeffrey Yim ◽  
Olivia Yau ◽  
Darwin F. Yeung ◽  
Teresa S. M. Tsang

Fabry disease (FD) is an X-linked lysosomal storage disorder caused by mutations in the galactosidase A (GLA) gene that result in deficient galactosidase A enzyme and subsequent accumulation of glycosphingolipids throughout the body. The result is a multi-system disorder characterized by cutaneous, corneal, cardiac, renal, and neurological manifestations. Increased left ventricular wall thickness represents the predominant cardiac manifestation of FD. As the disease progresses, patients may develop arrhythmias, advanced conduction abnormalities, and heart failure. Cardiac biomarkers, point-of-care dried blood spot testing, and advanced imaging modalities including echocardiography with strain imaging and magnetic resonance imaging (MRI) with T1 mapping now allow us to detect Fabry cardiomyopathy much more effectively than in the past. While enzyme replacement therapy (ERT) has been the mainstay of treatment, several promising therapies are now in development, making early diagnosis of FD even more crucial. Ongoing initiatives involving artificial intelligence (AI)-empowered interpretation of echocardiographic images, point-of-care dried blood spot testing in the echocardiography laboratory, and widespread dissemination of point-of-care ultrasound devices to community practices to promote screening may lead to more timely diagnosis of FD. Fabry disease should no longer be considered a rare, untreatable disease, but one that can be effectively identified and treated at an early stage before the development of irreversible end-organ damage.


Metabolites ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 14
Author(s):  
Petr G. Lokhov ◽  
Dmitry L. Maslov ◽  
Steven Lichtenberg ◽  
Oxana P. Trifonova ◽  
Elena E. Balashova

A laboratory-developed test (LDT) is a type of in vitro diagnostic test that is developed and used within a single laboratory. The holistic metabolomic LDT integrating the currently available data on human metabolic pathways, changes in the concentrations of low-molecular-weight compounds in the human blood during diseases and other conditions, and their prevalent location in the body was developed. That is, the LDT uses all of the accumulated metabolic data relevant for disease diagnosis and high-resolution mass spectrometry with data processing by in-house software. In this study, the LDT was applied to diagnose early-stage Parkinson’s disease (PD), which currently lacks available laboratory tests. The use of the LDT for blood plasma samples confirmed its ability for such diagnostics with 73% accuracy. The diagnosis was based on relevant data, such as the detection of overrepresented metabolite sets associated with PD and other neurodegenerative diseases. Additionally, the ability of the LDT to detect normal composition of low-molecular-weight compounds in blood was demonstrated, thus providing a definition of healthy at the molecular level. This LDT approach as a screening tool can be used for the further widespread testing for other diseases, since ‘omics’ tests, to which the metabolomic LDT belongs, cover a variety of them.


Author(s):  
Di Zhou ◽  
Ye Tian ◽  
Yao Lu ◽  
Xueying Yang

AbstractSitus inversus totalis (SIT) is an extremely uncommon congenital disease where the major organs of the body are transposed through the sagittal plane. Kartagener syndrome is a complication of SIT with immotility of bronchial cilia, bronchiectasis, and chronic sinusitis. There is no report describing patients with Kartagener syndrome who accept uni-portal segmentectomies for lung cancer in past studies. Here we report a 74-year-old female patient with both Kartagener syndrome and a small early-stage lung cancer lesion located in the apical segment of the left upper lobe (LS1). The pulmonary segment anatomy of the left upper lobe in this case, which had very rare variants, was presented and interpreted in detail. This patient underwent an anatomic segmentectomy to the LS1 and a partial excision to the left middle lobe with bronchiectasis through a single 3 cm length incision. We believe that the case can give surgeons some experience and inspiration.


Parasitology ◽  
1971 ◽  
Vol 62 (3) ◽  
pp. 479-488 ◽  
Author(s):  
Gwendolen Rees

Scanning electron-micrographs have shown the covering of microvilli on the surface of the redia of Parorchis acanthus. In the contracted state the elongated microvilli with bulbous extremities seen in the surface grooves may be the result of compression. The surface of the epidermis of the cercaria is smooth on a large area of the ventral surface and lattice-like with microvilli, laterally, anteriorly, dorsally and on the tail. The spines on the body can be withdrawn into sheaths by the contraction of muscle fibres inserted into the basement lamina below each spine.I would like to express my sincere gratitude to Dr I. ap Gwynn of this department for preparing the scanning electron-micrographs and the School of Engineering Science, University of North Wales, Bangor for the use of their stereoscan. I should also like to thank Mr M. C. Bibby for technical assistance and Professor E. G. Gray and Dr W. Sinclair for assistance with the transmission electron-micrographs.


Crustaceana ◽  
2013 ◽  
Vol 86 (13-14) ◽  
pp. 1695-1710 ◽  
Author(s):  
Susan E. Allen ◽  
A. G. Lewis

Locomotor appendage-body relationships were used to examine whether swimming or reduction in sinking rate is the more important function in the second nauplius and copepodid stages of Lepeophtheirus salmonis (Krøyer, 1837). Except for the similarity in swimming appendage surface areas without setae, the appendages of the two stages are morphologically distinct. Although the nauplius is smaller than the copepodid it has long slender appendages that, with setae, provide greater total surface area than the paddle-shaped copepodid thoracic legs. Copepodid thoracic legs are more similar to those used for swimming by planktonic copepods although with more limited propulsion capability. Naupliar appendages project from the body while copepodid appendages can be folded against the ventral surface, improving hydrodynamic flow as well as body position after attachment to a host. Both copepodid and naupliar appendages are of sufficient size that they should provide escape velocities of more than 100 mm ⋅ s−1. The nature and display of the naupliar appendages suggest they could be used to reduce sinking rate by as much as 64%, reducing the need to swim to maintain a suitable location in the water. Although copepodid thoracic legs could reduce sinking rate by over 40%, their position on the ventral surface and the nature of other appendages suggests a more important use, for orientation and attachment once a host is located.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Brittany Umer ◽  
David Good ◽  
Jozef Anné ◽  
Wei Duan ◽  
Ming Q. Wei

Solid tumour accounts for 90% of all cancers. The current treatment approach for most solid tumours is surgery, however it is limited to early stage tumours. Other treatment options such as chemotherapy and radiotherapy are non-selective, thus causing damage to both healthy and cancerous tissue. Past research has focused on understanding tumour cells themselves, and conventional wisdom has aimed at targeting these cells directly. Recent research has shifted towards understanding the tumour microenvironment and it’s differences from that of healthy cells/tissues in the body and then to exploit these differences for treatmeat of the tumour. One such approach is utilizing anaerobic bacteria. Several strains of bacteria have been shown to selectively colonize in solid tumours, making them valuable tools for selective tumour targeting and destruction. Amongst them, the anaerobicClostridiumhas shown great potential in penetration and colonization of the hypoxic and necrotic areas of the tumour microenvironment, causing significant oncolysis as well as enabling the delivery of therapeutics directly to the tumourin situ. Various strategies utilizingClostridiumare currently being investigated, and represent a novel area of emerging cancer therapy. This review provides an update review of tumour microenvironment as well as summary of the progresses and current status of Clostridial spore-based cancer therapies.


1961 ◽  
Vol 23 (1) ◽  
pp. 69-77 ◽  
Author(s):  
S. KULLANDER ◽  
B. SUNDÉN

SUMMARY A total of twenty-three human pre-viable foetuses (7–400 g.) were removed by abdominal hysterotomy (legal abortions) and studied during survival in an anoxic state at different temperatures. The duration of survival, as judged by ECG waves, at 37° c was about 3 hr.; it was longer for female foetuses than for males, and longer for large foetuses than for small ones. General reduction of the body-temperature to 4° c during periods varying between 30 min. and 6 hr. with subsequent rewarming to and maintenance at 37° c increased the survival time by a further 1–2 hr. The blood sugar did not decrease either during the period of survival or during hypothermia, but the non-protein nitrogen increased, while acidosis and hyperkalaemia developed. The glycogen content of the liver decreased during the anoxic period of survival and diminished further during hypothermia. The adrenal glands produced adrenaline in addition to noradrenaline during the anoxic phase, and this may occur in a very early stage of intrauterine life.


2020 ◽  
Vol 03 (04) ◽  
pp. 69-73
Author(s):  
Samira Mammadhasan Yagubova ◽  
◽  
Elchin Chingiz Akbarov ◽  
Tarana Nadir Mirzayeva ◽  
◽  
...  

During the staphylococcal infection, changes in the interaction of glandular cells, dystrophic and disorganizing pathologies in tissues, especially acute structural and hemodynamic changes in the stroma of the glands in the pituitary-adrenal-thyroid system, develop from the first day of the experiment. At the end of the experiment, on the background of a decrease in exudative processes, fibroplastic reactions are significantly activated, resulting in signs of incomplete regeneration – mainly sclerotic processes and cystic-atrophic changes in the parenchyma. Structural changes in tissues in the early stages of staphylococcal infection and the dynamics of development are characterized by specific symptoms in each of the glands. Since the pituitary gland is exposed to endogenous and exogenous factors earlier and more often than the adrenal glands, and the adrenal glands are earlier than the thyroid gland, dystrophic and destructive changes in the pituitary and adrenal glands are more pronounced at the early stage of the experiment. These morphological changes can change the hormonal status of the body and lead to dysfunction of the endocrine system as a whole – a decrease in the functional activity of the glands to some extent, and even inhibition of adenohypophyseal cells. Key words: staphylococcal infection, peritonitis, pituitary, adrenal and thyroid glands


2021 ◽  
pp. ijgc-2021-003004
Author(s):  
Jacqueline A Bohn ◽  
Miriam L Hernandez-Zepeda ◽  
Alyssa R Hersh ◽  
Elizabeth G Munro ◽  
Jenna M Kahn ◽  
...  

ObjectiveAbdominal radical hysterectomy in early-stage cervical cancer has higher rates of disease-free and overall survival compared with minimally invasive radical hysterectomy. Abdominal radical hysterectomy may be technically challenging at higher body mass index levels resulting in poorer surgical outcomes. This study sought to examine the influence of body mass index on outcomes and cost effectiveness between different treatments for early-stage cervical cancer.MethodsA Markov decision-analytic model was designed using TreeAge Pro software to compare the outcomes and costs of primary chemoradiation versus surgery in women with early-stage cervical cancer. The study used a theoretical cohort of 6000 women who were treated with abdominal radical hysterectomy, minimally invasive radical hysterectomy, or primary chemoradiation therapy. We compared the results for three body mass index groups: less than 30 kg/m2, 30–39.9 kg/m2, and 40 kg/m2 or higher. Model inputs were derived from the literature. Outcomes included complications, recurrence, death, costs, and quality-adjusted life years. An incremental cost-effectiveness ratio of less than $100 000 per quality-adjusted life year was used as our willingness-to-pay threshold. Sensitivity analyses were performed broadly to determine the robustness of the results.ResultsComparing abdominal radical hysterectomy with minimally invasive radical hysterectomy, abdominal radical hysterectomy was associated with 526 fewer recurrences and 382 fewer deaths compared with minimally invasive radical hysterectomy; however, abdominal radical hysterectomy resulted in more complications for each body mass index category. When the body mass index was 40 kg/m2 or higher, abdominal radical hysterectomy became the dominant strategy because it led to better outcomes with lower costs than minimally invasive radical hysterectomy. Comparing abdominal radical hysterectomy with primary chemoradiation therapy, recurrence rates were similar, with more deaths associated with surgery across each body mass index category. Chemoradiation therapy became cost effective when the body mass index was 40 kg/m2 or higher.ConclusionWhen the body mass index is 40 kg/m2 or higher, abdominal radical hysterectomy is cost saving compared with minimally invasive radical hysterectomy and primary chemoradiation is cost effective compared with abdominal radical hysterectomy. Primary chemoradiation may be the optimal management strategy at higher body mass indexes.


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