scholarly journals Polarity and reorganization of the endoplasmic reticulum during fertilization and ooplasmic segregation in the ascidian egg.

1993 ◽  
Vol 120 (6) ◽  
pp. 1337-1346 ◽  
Author(s):  
J E Speksnijder ◽  
M Terasaki ◽  
W J Hage ◽  
L F Jaffe ◽  
C Sardet
Keyword(s):  
Thick Layer ◽  
Second Phase ◽  
Calcium Waves ◽  
Cell Region ◽  
Vegetal Cortex ◽  
Before And After ◽  
Ooplasmic Segregation ◽  
Two Phases ◽  
Sperm Aster

During the first cell cycle of the ascidian egg, two phases of ooplasmic segregation create distinct cytoplasmic domains that are crucial for later development. We recently defined a domain enriched in ER in the vegetal region of Phallusia mammillata eggs. To explore the possible physiological and developmental function of this ER domain, we here investigate its organization and fate by labeling the ER network in vivo with DiIC16(3), and observing its distribution before and after fertilization in the living egg. In unfertilized eggs, the ER-rich vegetal cortex is overlaid by the ER-poor but mitochondria-rich subcortical myoplasm. Fertilization results in striking rearrangements of the ER network. First, ER accumulates at the vegetal-contraction pole as a thick layer between the plasma membrane and the myoplasm. This accompanies the relocation of the myoplasm toward that region during the first phase of ooplasmic segregation. In other parts of the cytoplasm, ER becomes progressively redistributed into ER-rich and ER-poor microdomains. As the sperm aster grows, ER accumulates in its centrosomal area and along its astral rays. During the second phase of ooplasmic segregation, which takes place once meiosis is completed, the concentrated ER domain at the vegetal-contraction pole moves with the sperm aster and the bulk of the myoplasm toward the future posterior side of the embryo. These results show that after fertilization, ER first accumulates in the vegetal area from which repetitive calcium waves are known to originate (Speksnijder, J. E. 1992. Dev. Biol. 153:259-271). This ER domain subsequently colocalizes with the myoplasm to the presumptive primary muscle cell region.

scholarly journals Biphasic pattern in the effect of severe measles infection; the difference between additive and multiplicative scale

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Nhat Thanh Hoang Le ◽  
Nhan Thi Ho ◽  
Bryan Grenfell ◽  
Stephen Baker ◽  
Ronald B. Geskus
Keyword(s):  
Infectious Diseases ◽  
Hospital Admission ◽  
Measles Virus ◽  
Hospital Admissions ◽  
Admission Rate ◽  
Second Phase ◽  
Before And After ◽  
The Difference ◽  
Two Phases ◽  
Additive Scale

Abstract Background Infection with measles virus (MeV) causes immunosuppression and increased susceptibility to other infectious diseases. Only few studies reported a duration of immunosuppression, with varying results. We investigated the effect of immunosuppression on the incidence of hospital admissions for infectious diseases in Vietnamese children. Methods We used retrospective data (2005 to 2015; N = 4419) from the two pediatric hospitals in Ho Chi Minh City, Vietnam. We compared the age-specific incidence of hospital admission for infectious diseases before and after hospitalization for measles. We fitted a Poisson regression model that included gender, current age, and time since measles to obtain a multiplicative effect measure. Estimates were transformed to the additive scale. Results We observed two phases in the incidence of hospital admission after measles. The first phase started with a fourfold increased rate of admissions during the first month after measles, dropping to a level quite comparable to children of the same age before measles. In the second phase, lasting until at least 6 years after measles, the admission rate decreased further, with values up to 20 times lower than in children of the same age before measles. However, on the additive scale the effect size in the second phase was much smaller than in the first phase. Conclusion The first phase highlights the public health benefits of measles vaccination by preventing measles and immune amnesia. The beneficial second phase is interesting, but its strength strongly depends on the scale. It suggests a complicated interaction between MeV infection and the host immunity.

Fertilization and ooplasmic movements in the ascidian egg

Development ◽  
1989 ◽  
Vol 105 (2) ◽  
pp. 237-249 ◽  
Author(s):  
C. Sardet ◽  
J. Speksnijder ◽  
S. Inoue ◽  
L. Jaffe
Keyword(s):  
Polar Body ◽  
Surface Velocity ◽  
Second Phase ◽  
Animal Pole ◽  
Male Pronucleus ◽  
Vegetal Pole ◽  
Female Pronucleus ◽  
Ooplasmic Segregation ◽  
Second Polar Body ◽  
Sperm Aster

Using light microscopy techniques, we have studied the movements that follow fertilization in the denuded egg of the ascidian Phallusia mammillata. In particular, our observations show that, as a result of a series of movements described below, the mitochondria-rich subcortical myoplasm is split in two parts during the second phase of ooplasmic segregation. This offers a potential explanation for the origin of larval muscle cells from both posterior and anterior blastomeres. The first visible event at fertilization is a bulging at the animal pole of the egg, which is immediately followed by a wave of contraction, travelling towards the vegetal pole with a surface velocity of 1.4 microns s-1. This wave accompanies the first phase of ooplasmic segregation of the mitochondria-rich subcortical myoplasm. After this contraction wave has reached the vegetal pole after about 2 min, a transient cytoplasmic lobe remains there until 6 min after fertilization. Several new features of the morphogenetic movements were then observed: between the extrusion of the first and second polar body (at 5 and 24–29 min, respectively), a series of transient animal protrusions form at regular intervals. Each animal protrusion involves a flow of the centrally located cytoplasm in the animal direction. Shortly before the second polar body is extruded, a second transient vegetal lobe (‘the vegetal button’) forms, which, like the first, resembles a protostome polar lobe. Immediately after the second polar body is extruded, three events occur almost simultaneously: first, the sperm aster moves from the vegetal hemisphere to the equator. Second, the bulk of the vegetally located myoplasm moves with the sperm aster towards the future posterior pole, but interestingly about 20% remains behind at the anterior side of the embryo. This second phase of myoplasmic movement shows two distinct subphases: a first, oscillatory subphase with an average velocity of about 6 microns min-1, and a second steady subphase with a velocity of about 26 microns min-1. The myoplasm reaches its final position as the male pronucleus with its surrounding aster moves towards the centre of the egg. Third, the female pronucleus moves towards the centre of the egg to meet with the male pronucleus. Like the myoplasm, the migrations of both the sperm aster and the female pronucleus shows two subphases with distinctly different velocities. Finally, the pronuclear membranes dissolve, a small mitotic spindle is formed with very large asters, and at about 60–65 min after fertilization, the egg cleaves.

scholarly journals Involvement of NO in Antinociception of NSAIDS in Murine Formalin Hind Paw Assay

Drug Research ◽  
2020 ◽  
Vol 70 (04) ◽  
pp. 145-150 ◽  
Author(s):  
Viviana Noriega ◽  
Hugo F. Miranda ◽  
Juan Carlos Prieto ◽  
Ramón Sotomayor-Zárate ◽  
Fernando Sierralta
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Dose Response ◽  
Rank Order ◽  
Linear Regression Analysis ◽  
Second Phase ◽  
Response Curves ◽  
Before And After ◽  
Two Phases ◽  
Phase Phase

AbstractThere are different animal models to evaluate pain among them the formalin hind paw assay which is widely used since some of its events appear to be similar to the clinical pain of humans. The assay in which a dilute solution of formalin is injected into the dorsal hindpaw of a murine produces two ‘phases’ of pain behavior separated by a inactive period. The early phase (Phase I) is probably due to direct activation of nociceptors and the second phase (Phase II) is due to ongoing inflammatory input and central sensitization. Mice were used to determine the potency antinociceptive of piroxicam (1,3,10,and 30 mg/kg), parecoxib (0.3, 1,3,10 and 30 mg/kg), dexketoprofen (3,10,30 and 100 mg/kg) and ketoprofen (3,10,30 and 100 mg/kg). Dose-response for each NSAIDs were created before and after 5 mg/kg of L-NAME i.p. or 5 mg/kg i.p. of 7-nitroindazole. A least-squares linear regression analysis of the log dose–response curves allowed the calculation of the dose that produced 50% of antinociception (ED50) for each drug. The ED50 demonstrated the following rank order of potency, in the phase I: piroxicam > dexketoprofen > ketoprofen > parecoxib and in the phase II: piroxicam > ketoprofen > parecoxib > dexketoprofen. Pretreatment of the mice with L-NAME or 7-nitroindazol induced a significant increase of the analgesic power of the NSAIDs, with a significant reduction of the ED50. It is suggested that NO may be involved in both phases of the trial, which means that nitric oxide regulates the bioactivity of NSAIDs.

scholarly journals The roles of Fzy/Cdc20 and Fzr/Cdh1 in regulating the destruction of cyclin B in space and time

2002 ◽  
Vol 157 (7) ◽  
pp. 1139-1149 ◽  
Author(s):  
Jordan W. Raff ◽  
Kim Jeffers ◽  
Jun-yong Huang
Keyword(s):  
Cell Cycle ◽  
Triple Point ◽  
Mitotic Spindle ◽  
Cyclin B ◽  
Second Phase ◽  
Point Mutant ◽  
Two Phases ◽  
Drosophila Cells

In Drosophila cells cyclin B is normally degraded in two phases: (a) destruction of the spindle-associated cyclin B initiates at centrosomes and spreads to the spindle equator; and (b) any remaining cytoplasmic cyclin B is degraded slightly later in mitosis. We show that the APC/C regulators Fizzy (Fzy)/Cdc20 and Fzy-related (Fzr)/Cdh1 bind to microtubules in vitro and associate with spindles in vivo. Fzy/Cdc20 is concentrated at kinetochores and centrosomes early in mitosis, whereas Fzr/Cdh1 is concentrated at centrosomes throughout the cell cycle. In syncytial embryos, only Fzy/Cdc20 is present, and only the spindle-associated cyclin B is degraded at the end of mitosis. A destruction box–mutated form of cyclin B (cyclin B triple-point mutant [CBTPM]–GFP) that cannot be targeted for destruction by Fzy/Cdc20, is no longer degraded on spindles in syncytial embryos. However, CBTPM–GFP can be targeted for destruction by Fzr/Cdh1. In cellularized embryos, which normally express Fzr/Cdh1, CBTPM–GFP is degraded throughout the cell but with slowed kinetics. These findings suggest that Fzy/Cdc20 is responsible for catalyzing the first phase of cyclin B destruction that occurs on the mitotic spindle, whereas Fzr/Cdh1 is responsible for catalyzing the second phase of cyclin B destruction that occurs throughout the cell. These observations have important implications for the mechanisms of the spindle checkpoint.

Digestion in the tick,Argas persicus, Oken.

Parasitology ◽  
1964 ◽  
Vol 54 (3) ◽  
pp. 423-440 ◽  
Author(s):  
R. J. Tatchell
Keyword(s):  
Epithelial Cells ◽  
Waste Product ◽  
Aminopeptidase Activity ◽  
Second Phase ◽  
Rapid Phase ◽  
Argas Persicus ◽  
Intracellular Digestion ◽  
Two Phases

1.Studies on the histological changes during digestion in Argas persicus reveal that the ingestion of blood is accompanied by the destruction of the existing gut epithelial cells.2.The blood remains unlysed for 2–3 days while a new epithelium develops which contains cells that secrete a saliva-fast PAS-positive colloid that causes haemolysis.3.Other epithelial cells remove the freed erythrocytic nuclei by phagocytosis.4.Most of the gut cells then absorb protein from the lumen and intracellular digestion takes place leaving pure haematin granules as the waste product of the digestion of haemoglobin.5.After the initial rapid phase of digestion only relatively few cells show signs of absorptive and digestive activity.6.Absorption of protein is accompanied by increased alkaline phosphatase activity in the microvilli of the cell border; this activity is lost once absorption finishes and digestion begins.7.Strong aminopeptidase activity can be demonstrated at the border of some of the protein vacuoles.8.In vitro tests show that the gut proteinase is active only in the acid range with peaks at pH 2·6 and 3·8 and has a Km of 0·32 % with bovine serum albumin as substrate.9.In vivo data show that digestion, after haemolysis has occurred, takes place in two phases; the first is rapid and lasts approximately 1–2 weeks and is followed by the second phase which is slow and remains constant until the next blood feed.10.The proportion of the blood meal which remains after the rapid phase of digestion is determined by the sex and developmental stage of the tick and within each category it is constant and serves, in the absence of significant fat and glycogen reserves, as a food reserve.

scholarly journals Evaluation of Albumin Utilization in a Major Teaching Hospital in Iran Before and After Guideline Implementation

2021 ◽  
Author(s):  
Shahriyar Shahbazi Khamas ◽  
Iman Mirbagheri ◽  
Anoush Dehnadi-Moghaddam ◽  
Asieh Ashouri ◽  
Atefeh Jafari
Keyword(s):  
Teaching Hospital ◽  
Guideline Implementation ◽  
Hospital Costs ◽  
P Value ◽  
Second Phase ◽  
Inappropriate Use ◽  
Before And After ◽  
Major Teaching Hospital ◽  
Major Teaching ◽  
Two Phases

Background: Inappropriate use of drugs is one of the major issues in health care system. Rational drug utilization based on the appropriate guidelines has an important role in management of use of expensive medications. We aimed to evaluate albumin usage's appropriateness based on evidence-based indications before and after implementing albumin prescription guideline in a teaching hospital. Methods: This study was performed in two phases. During two-month periods, all the patients who were ordered to receive albumin were evaluated. The first phase was done in November and December of 2017, during which, based on physicians' comments, the guideline was finalized and then implemented. Phase two was performed in May and June 2018. Results: Albumin was prescribed appropriately in 33 patients (55%) in the first phase and 43 (70%) patients in the second phase. 299 vials in the first phase and 456 vials in the second phase were prescribed which 198 vials (66%) and 394 (86%) vials were used with appropriate indications, respectively. The number of vials consumed with inappropriate indication decreased significantly from 101 vials (34%) in the first phase to 62 vials (14%) in the second phase (P-value=0.01). The average cost of the inappropriate indication per patient decreased from $197.3 ± 131.6 in the first phase to $183.5 ± 126.8 in the second phase (P-value=0.52). Conclusion: This study showed implementing a DUE program and designing a guideline for rational prescribing of albumin and interventional methods can optimize treatment duration, significantly decrease inappropriate usage, and avoid unnecessary hospital costs.

scholarly journals Cost-effectiveness analysis of hernioplasties before and after the implementation of the ACERTO project

2020 ◽  
Vol 47 ◽  
Author(s):  
JOSÉ EDUARDO DE AGUILAR NASCIMENTO ◽  
ALBERTO BICUDO SALOMÃO ◽  
MARA REGINA ROSA RIBEIRO ◽  
ROBERTA FERREIRA DA SILVA ◽  
WESLEY SANTANA CORREA ARRUDA
Keyword(s):  
Length Of Stay ◽  
Surgical Site Infection ◽  
Hospital Costs ◽  
University Hospital ◽  
Outcome Variable ◽  
Second Phase ◽  
Site Infection ◽  
Cost Information ◽  
Before And After ◽  
Two Phases

ABSTRACT Objective: to compare hospital costs and clinical outcomes in inguinal and incisional hernioplasty before and after implementation of the ACERTO project in a university hospital. Methods: retrospective study of 492 patients undergoing either inguinal hernioplasty (n=315) or incisional hernioplasty (n=177). The investigation involved two phases: between January 2002 and December 2005, encompassing cases admitted before the implementation of the ACERTO protocol (PRE-ACERTO period), and the other phase, with cases operated between January 2006 and December 2011, after the implementation of the protocol (ACERTO period). The main outcome variable was the comparison of the mean hospital costs between the two periods. As secondary endpoints, we analyzed the length of stay, the surgical site infection rate and mortality. We used the cost method suggested by Public Sector Cost Information System. Results: surgical site infection was higher (p = 0.039) in the first phase of the study for both inguinal hernia operations (2 (1.6%) versus 0 (0%) cases) and incisional hernioplasty (5 (7.6%) versus 3 (2.7%) cases). The length of stay decreased one day after the implementation of the ACERTO protocol (p=0.005). There was a reduction in costs per patient from R$ 4,328.58 per patient in the first phase to R$ 2,885.72 in the second phase (66.7% reduction). Conclusion: there was a reduction in infectious morbidity, length of stay and hospital costs in hernioplasty after the implementation of the ACERTO protocol.

scholarly journals Dynamic changes in anxiety level before and after reading and watching different types of online articles and videos respectively: A Pilot Study

2021 ◽  
Author(s):  
Sizhe Zhou ◽  
Keying Liu
Keyword(s):  
High School Students ◽  
Dynamic Effect ◽  
Anxiety Level ◽  
Second Phase ◽  
School Students ◽  
Before And After ◽  
Anxiety Levels ◽  
Two Phases ◽  
Ecological Momentary

In recent years, researchers studying anxiety in high school students have determined that therapeutic videos and articles are effective as auxiliary intervention methods, but the specific types of videos or articles that are most effective still remain unclear. Current research has focused on the dynamic effect of various types of videos or articles on adolescents' anxiety levels, with the aim of finding suitable types of videos or articles to be used as materials during interventions. The study is divided into two phases. In the first phase of the study, a questionnaire was distributed to a total of 2120 participants from China regarding their anxiety level and their preferred materials during online surfing, The results indicate that five types of materials were related to adolescents’ anxiety levels. In the second phase of the study, Ecological Momentary Assessment was used to continuously measure 30 participants’ anxiety levels over the course of ten days. The results show that while scenic video, online fiction, classic literature, and literature criticism affected an individual’s emotions positively. There was no significant effect when entertainment videos were used. In addition, only scenic videos were able to alleviate anxiety in the long-term.

scholarly journals Therapeutic efficacy and pharmacological safety of parenteral supplementation of different concentrations of copper in cows

2012 ◽  
Vol 55 (1) ◽  
pp. 25-35
Author(s):  
J. R. García-Díaz ◽  
H. Munyori-Nderitu ◽  
M. Cuesta-Mazorra ◽  
R. Quiñones-Ramos ◽  
J. M. Figueredo-Ross ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Blood Serum ◽  
Control Group ◽  
Second Phase ◽  
Hepatic Enzymes ◽  
Physiological Level ◽  
Before And After ◽  
Two Phases ◽  
The One ◽  
The Impact

Abstract. The objective of the present study was to determine the parenteral dosage of the trace mineral copper (Cu) which re-establishes serum and hepatic levels in hypocupperhemic animals without causing intoxication in the liver or residuals in milk. The experiment was carried out in two phases; in the first phase, 20 hypocupperhemic animals were used. Those were divided into 4 groups of 5 cows each: 3 groups which received 25, 50 and 100 mg of Cu respectively and 1 control group without supplementation, but with induced copraemia 5 days before and after the treatment. The milk of the cows treated with 100 mg Cu was examined for residuals of this element for one month. In the second phase, 25 animals were selected and divided into 5 groups of 5 cows each: 1 control group and 4 groups which received 25, 50, 100 and 200 mg of Cu respectively. The impact of this Cu dosages on liver reserves of this element, on hepatic enzymes (alanine-amine-transaminase, aspartate-amine-transferase, alkaline phosphatase and glutamate dehydrogenase) and on bilirubin was analyzed. The groups treated with 50 and 100 mg Cu showed increased levels in blood serum and hepatic tissues (P<0.05) in comparison to the control group and the one treated with 25 mg, obtaining the physiological level considered normal in cows during 60 days without an effect to the level of Cu in milk or to the liver’s enzymatic activity. We conclude that treatment with this dosage results in a restoration of the Cu concentration in blood serum and hepatic tissues without toxic effects or residuals.

Calcium antagonists and hormone release

1982 ◽  
Vol 101 (1) ◽  
pp. 5-9 ◽  
Author(s):  
Antonino Barbarino ◽  
Laura De Marinis ◽  
Antonio Mancini ◽  
Ofa Makhoul
Keyword(s):  
Luteinizing Hormone ◽  
Calcium Antagonists ◽  
Essential Role ◽  
Normal Subjects ◽  
Constant Infusion ◽  
Second Phase ◽  
Lh Release ◽  
Two Phases

Abstract. Recent in vitro studies have demonstrated that Ca2+ plays an essential role in gonadotrophin-releasing hormone (GnRH)-stimulated luteinizing hormone (LH) release. In vivo, we have previously shown that verapamil, a substance known to inhibit calcium entry into cells, is capable of inhibiting basal gonadotrophin release as well as the release of luteinizing hormone and follicle-stimulating hormone (FSH) in response to an iv bolus of GnRH. We have examined the effects of calcium antagonists on the two phases of pituitary LH release in response to constant GnRH infusion in normal subjects. In 6 men, constant infusion of GnRH (0.2 μg/min × 4 h) resulted in the expected biphasic LH response, with an initial rapid release of LH during the first hour of infusion, followed by a second phase release during the subsequent 3 h. When verapamil (5 mg/h) was infused together with GnRH over a 4 h period, a significant decline of the rapid as well as delayed release of pituitary LH occurred. During the calcium antagonist infusion FSH release was also inhibited, indicating that Ca2+ is also important for the release of this hormone. Our data demonstrate that Ca2+ plays an essential role in the mechanism of GnRH action on both phases of LH release and the release of FSH in normal subjects.

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