Menopause as a Normal Physiological Event or as a Disease

1994 ◽  
pp. 59-65 ◽  
Author(s):  
Patricia A. Kaufert ◽  
Margaret Lock ◽  
Sonja McKinlay ◽  
Nancy Avis
Keyword(s):  
Physiological Event

Light-dependent hydration of the space surrounding photoreceptors in the cat retina

1994 ◽  
Vol 11 (4) ◽  
pp. 743-752 ◽  
Author(s):  
Jian-Dong Li ◽  
Victor I. Govardovskii ◽  
Roy H. Steinberg
Keyword(s):  
Mathematical Model ◽  
Time Course ◽  
Distal Portion ◽  
Subretinal Space ◽  
Volume Increase ◽  
Physiological Event ◽  
Cat Retina ◽  
Interphotoreceptor Matrix ◽  
Space Marker

AbstractWe have studied the effect of retinal illumination on the concentration of the extracellular space marker tetramethylammonium (TMA+) in the dark-adapted cat retina using double-barreled ion-selective microelectrodes. The retina was loaded with TMA+ by a single intravitreal injection. Retinal illumination produced a slow decrease in , which was maximal in amplitude in the most distal portion of the space surrounding photoreceptors, the subretinal space. The light-evoked decrease in was considerably slower and of a different overall time course than the light-evoked decrease in , also recorded in the subretinal space. decreased to a peak at 38 s after the onset of illumination, then slowly recovered towards the baseline, and transiently increased following the offset of illumination. It resembled the light-evoked decreases previously recorded in the in vitro preparations of frog (Huang & Karwoski, 1990, 1992) and chick (Li et al., 1992, 1994) but was considerably larger in amplitude, 22% compared with 7%. As in frog, where it was first recorded, the light-evoked decrease is considered to originate from a light-evoked increase in the volume of the subretinal space (or subretinal hydration). A mathematical model accounting for diffusion predicted that the volume increase underlying the response was 63% on average and could be as large as 95% and last for minutes. The estimated volume increase was then used to examine its effect on K+ concentration in the subretinal space. We conclude that a light-dependent hydration of the subretinal space represents a significant physiological event in the intact cat eye, which should affect the organization of the interphotoreceptor matrix, and the concentrations of all ions and metabolites located in the subretinal space.

PhysioEx: Visual Analysis of Physiological Event Streams

2016 ◽  
Vol 35 (3) ◽  
pp. 331-340 ◽  
Author(s):  
Rishikesan Kamaleswaran ◽  
Christopher Collins ◽  
Andrew James ◽  
Carolyn McGregor
Keyword(s):  
Visual Analysis ◽  
Physiological Event

scholarly journals Phagocytosis: a repertoire of receptors and Ca2+ as a key second messenger

2008 ◽  
Vol 28 (5) ◽  
pp. 287-298 ◽  
Author(s):  
Alirio J. Melendez ◽  
Hwee Kee Tay
Keyword(s):  
Phagosome Maturation ◽  
Physiological Event ◽  
Signalling Molecules ◽  
Complex Process ◽  
Large Particles ◽  
A Cell ◽  
Unicellular Organisms ◽  
Multicellular Organisms ◽  
Innate Defence

Receptor-mediated phagocytosis is a complex process that mediates the internalization, by a cell, of other cells and large particles; this is an important physiological event not only in mammals, but in a wide diversity of organisms. Of simple unicellular organisms that use phagocytosis to extract nutrients, to complex metazoans in which phagocytosis is essential for the innate defence system, as a first line of defence against invading pathogens, as well as for the clearance of damaged, dying or dead cells. Evolution has armed multicellular organisms with a range of receptors expressed on many cells that serve as the molecular basis to bring about phagocytosis, regardless of the organism or the specific physiological event concerned. Key to all phagocytic processes is the finely controlled rearrangement of the actin cytoskeleton, in which Ca2+ signals play a major role. Ca2+ is involved in cytoskeletal changes by affecting the actions of a number of contractile proteins, as well as being a cofactor for the activation of a number of intracellular signalling molecules, which are known to play important roles during the initiation, progression and resolution of the phagocytic process. In mammals, the requirement of Ca2+ for the initial steps in phagocytosis, and the subsequent phagosome maturation, can be quite different depending on the type of cell and on the type of receptor that is driving phagocytosis. In this review we discuss the different receptors that mediate professional and non-professional phagocytosis, and discuss the role of Ca2+ in the different steps of this complex process.

STUDIES ON THE INVOLVEMENTOF GPIIb/IIIa COMPLEX IN PLATELET AGGREGATION WITH TWO MONOCLONAL ANTIBODIES

1987 ◽  
Author(s):  
J J Ryckewaert ◽  
O Valiron ◽  
I A Newton ◽  
E Concord ◽  
M Prenant ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Platelet Aggregation ◽  
Platelet Function ◽  
Fab Fragment ◽  
Similar Activity ◽  
Physiological Event ◽  
Functional Studies ◽  
Fibrinogen Receptor ◽  
Stimulatory Activity

The involvement of the glycoproteins IIb/IIIa in the binding of fibrinogen to stimulated platelets and in the aggregation of these cells is well documented. Monoclonal antibodies (MoAb) directedagainst these two glycoproteins are useful probes in functional studies. Two MoAbs have been obtained against thetwo glycoproteins in their heterodimer form. Both MoAbs immunoprecipitate the complex from platelet lysates and only bind to platelets if the complex of the two glycoproteins is not dissociated.Studies onthe effect of the two MoAbs on platelet function have been performed. Firstly CS9,a murine IgG 2a, inhibited the binding of fibrinogen to stimulated platelets and prevented platelet aggregation. Fab CS9 obtained bypapain digestion had a similar activity. The binding of I125 Fab CS9 to resting platelets was similar to that of ADP-stimulated platelets (30 000 MoAbs/platelet). Similar behaviour of MoAbs against GPIIb/IIIa has been repeatedly reported and is considered as evidence that the fibrinogen receptor is the GPIIb/IIIa complex. The second MoAb (CS3),an IgGJ, subtype had a different action on platelet function.Contrary to all other known antibodies directed against the GPIIb/IIIa complex, CS3 or (Fab’2)CS3 induced the bindingof fibrinogen to platelet in the absence ofany plateletstimuli. Washed platelets in the presenceof CS3 underwent immediate and extensive aggregation, even in the absenceof fibrinogen. The stimulatory activity of MoAb CS3 on platelet can be eliminated by PGEJ. Monovalent CS3 (Fab fragment) failed to exhibit the properties of the parent antibody and had no effect on platelet function. The most likely explanation of the action of CS3 on platelet function may be that crosslinking of two GPIIb/IIIa complex mediated by the antibody leads to platelet stimulation. Whetheror not this mechanism is evocative of a physiological event when platelets are stimulated remains to be demonstrated. When both MoAbs are used in combination, the binding of fibrinogen and platelet aggregation are prevented by CS9 despite the stimulatory activity of CS3. Thus both MoAbsareable to bind to the GPIIb/IIIa complexat the same time.

scholarly journals Calsequestrin: more than ‘only’ a luminal Ca2+ buffer inside the sarcoplasmic reticulum

1998 ◽  
Vol 337 (1) ◽  
pp. 19-22 ◽  
Author(s):  
Csaba SZEGEDI ◽  
Sándor SÁRKÖZI ◽  
Anke HERZOG ◽  
István JÓNA ◽  
Magdolna VARSÁNYI
Keyword(s):  
Skeletal Muscle ◽  
Sarcoplasmic Reticulum ◽  
Striated Muscle ◽  
Hill Coefficient ◽  
Channel Activity ◽  
Open Probability ◽  
Physiological Event ◽  
Contraction Coupling ◽  
Open Time ◽  
The Mean

In striated muscle, the sarcoplasmic reticulum (SR) Ca2+ release/ryanodine receptor (RyR) channel provides the pathway through which stored Ca2+ is released into the myoplasm during excitation–contraction coupling. Various luminal Ca2+-binding proteins are responsible for maintaining the free [Ca2+] at 10-3–10-4 M in the SR lumen; in skeletal-muscle SR, it is mainly calsequestrin. Here we show that, depending on its phosphorylation state, calsequestrin selectively controls the RyR channel activity at 1 mM free luminal [Ca2+]. Calsequestrin exclusively in the dephosphorylated state enhanced the open probability by approx. 5-fold with a Hill coefficient (h) of 3.3, and increased the mean open time by about 2-fold, i.e. solely dephosphorylated calsequestrin regulates Ca2+ release from the SR. Because calsequestrin has been found to occur mainly in the phosphorylated state in the skeletal-muscle SR for the regulation of RyR channel activity, the dephosphorylation of calsequestrin would appear to be a quintessential physiological event.

Narratives on Pain and Comfort: Casey's Story

1996 ◽  
Vol 24 (4) ◽  
pp. 292-293 ◽  
Author(s):  
Jay Gabb
Keyword(s):  
College Student ◽  
Pain Management ◽  
Religious Faith ◽  
Physiological Event ◽  
Parish Priest ◽  
Pharmacological Response ◽  
Societal Response ◽  
Human Need ◽  
Medical Situation ◽  
Extreme Pain

Pain can be a body-wrenching curse. Yet it is often a life-defining and supporting blessing!Pain is a distinct physiological event, yet it is also an emotional, social, spiritual, and economic force. Pain in its more destructive form alters lives, changes relationships, and disrupts families.Quality pain management should not be just a pharmacological response to a medical situation; it must also be a theological, ethical, and societal response to human need. Appropriate pain management is a gift to both the receiver and the provider. As a parish priest, a supervisor of pastoral services, and an ethics resource specialist, I have seen many pain-filled situations that have involved multiples of these dimensions.Born in 1969, Casey died in 1995, just a few months after his twenty-sixth birthday. Casey was an intelligent, charismatic college student, strong in religious faith, who had few problems … at least until one day in the summer of 1994. That day he began to suffer extreme pain in his lower stomach and bowels.

scholarly journals Retention of lymphocytes in the subcapsular sinus of lymph nodes: A physiological event?

1990 ◽  
Vol 53 (5) ◽  
pp. 531-541 ◽  
Author(s):  
Guy SAINTE-MARIE ◽  
Fuh-Shiong PENG
Keyword(s):  
Lymph Nodes ◽  
Physiological Event ◽  
Subcapsular Sinus

Hormone replacement therapy: update and practical prescribing

2021 ◽  
Vol 32 (4) ◽  
pp. 148-156
Author(s):  
Nikki Noble
Keyword(s):  
Hormone Replacement Therapy ◽  
Side Effects ◽  
Replacement Therapy ◽  
Health Professionals ◽  
Hormone Replacement ◽  
Reproductive Function ◽  
Physiological Event ◽  
The Common ◽  
Follicular Activity

Peri-menopause and menopause are a normal part of ageing. Nikki Noble gives an overview of hormone replacement therapy and practical prescribing tips Menopause is a physiological event of ovarian failure due to a loss of ovarian follicular activity. This leads to a lack of oestrogen, resulting in the cessation of menstruation and loss of reproductive function. This article discusses the symptoms of menopause and treatment with hormone replacement therapy. This includes practical prescribing, side effects and long-term benefits and risks. The current shortages of hormone replacement therapy are also addressed. The aim of this article is to enable health professionals to define menopause and gain an understanding of the symptoms associated with it. After reading this article you should be able to: describe when peri-menopause and menopause occur, describe the common symptoms that may be experienced during peri-menopause and menopause, understand of the hormones used in hormone replacement therapy, and understand the practical prescribing of hormone replacement therapy and the benefits, risks, contraindications and side-effects.

PAROXYSMAL FUSSING IN INFANCY, SOMETIMES CALLED "COLIC"

PEDIATRICS ◽  
1954 ◽  
Vol 14 (5) ◽  
pp. 421-435 ◽  
Author(s):  
MORRIS A. WESSEL ◽  
JOHN C. COBB ◽  
EDITH B. JACKSON ◽  
GEORGE S. HARRIS ◽  
ANN C. DETWILER
Keyword(s):  
Weight Gain ◽  
Birth Weight ◽  
Family History ◽  
Educational Level ◽  
Frequent Occurrence ◽  
Infantile Colic ◽  
Physiological Event ◽  
History Of ◽  
Almost All ◽  
Methods Of Treatment

The literature on "infantile colic" or "paroxysmal fussing" is reviewed. The frequent occurrence of a regular evening fussy period in two groups of infants is reported as indicative that this is a normal physiological event of the first few weeks of life. The longitudinal records of 98 infants who were study subjects of the Yale Rooming-In Project were analyzed with respect to incidence, duration, and severity of "paroxysmal fussing." Forty-eight of the infants were classified as "fussy" and 50 as "contented." The "fussy" babies typically began to have their paroxysms in the second week of life and ceased to have them at about eight weeks. Almost all of them were more fussy in the evening hours than in the morning. The rationale of various methods of treatment is discussed. The "fussy" group was similar to the "contented" group as regards details of feeding, birth weight, weight gain, sex, educational level of the mother, and family history of allergy. Of the 48 "fussy" infants, family tension was judged to be an important contributing cause in 22 cases, allergy in six cases; both allergy and family tension together in nine cases; in 11 cases there was no apparent cause. "Paroxysmal fussing" or "infantile colic" is possibly one of the earliest somatic responses to the presence of tension in the environment. The particular degree to which any infant reacts is probably determined by constitutional factors.

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