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1.
Acta Endocrinol (Buchar) ; 12(4): 481-484, 2016.
Article in English | MEDLINE | ID: mdl-31149136

ABSTRACT

BACKGROUND: Patients with acromegaly (caused by growth-hormone-secreting pituitary adenomas) are at increased risk of hypopituitarism, in particular hypogonadotropic hypogonadism, before and after multimodal therapy. In affected women of reproductive age, fertility is impaired and complex fertility treatments are needed to achieve conception. CASE PRESENTATION: We present the case of a young woman with acromegaly caused by a GH-secreting macroadenoma with suprasellar and bilateral cavernous sinus extension; hypogonadotropic hypogonadism and secondary hypothyroidism were present from the initial evaluation. Neurosurgical intervention was repeatedly recommended but the patient refused it initially; also she was non-compliant to the medical treatment of acromegaly. Transsphenoidal tumor debulking with adjuvant gamma-knife radiotherapy was eventually performed. Following treatment persistent active acromegaly and hypogonadotropic hypogonadism were diagnosed. Under chronic estroprogestative replacement therapy, the patient conceived and delivered a full-term healthy newborn without any complications. Possible mechanisms are discussed. CONCLUSIONS: Secondary hypogonadotropic hypogonadism in pituitary patients, even when considered permanent (after surgery and radiotherapy), can exceptionally allow spontaneous conception and normal course of pregnancy.

2.
J Endocrinol Invest ; 37(11): 1081-90, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25125022

ABSTRACT

AIM OF THE STUDY: To describe morphological and functional cardiovascular changes in acromegaly (ACM) patients, as well as to investigate the ability of Doppler-based myocardial deformation imaging (DMI) to characterize subtle dysfunction in ACM. METHODS: 69 patients (pts) with ACM (mean age 47 ± 10 years, 27 men) and 31 controls (mean age 43 ± 16 years, matched for age and gender) were recruited. Standard echocardiography and DMI data were obtained for all patients. Peak systolic longitudinal strain values (S) were determined for the left and right ventricles. Radial S was measured at the level of the mid inferolateral segment. Using a high-resolution echo-tracking system, the main indices of arterial stiffness were measured. RESULTS: Of the ACM subjects, 57 had active disease (group A), and 12 controlled ACM (group B). All pts with ACM presented structural changes: a higher LV indexed mass (112 ± 36, 118 ± 23 vs 74 ± 18 g/m(2), p < 0.001) and a higher relative wall thickness (0.45 ± 0.09, 0.50 ± 0.07 vs 0.40 ± 0.07, p = 0.003) compared to controls. Also, ACM pts had functional changes: reduced LV ejection fraction (57 ± 5, 55 ± 5 vs 64 ± 4%, p < 0.001) and altered diastolic function (E/A 1.0 ± 0.4, 1.1 ± 0.1 vs 1.3 ± 0.3, p = 0.005) compared to controls. Both longitudinal and radial LV S values were lower in ACM compared to controls: -16.5 ± 3.5, -16.8 ± 4.3 vs -21.5 ± 3.8%, p < 0.001 for longitudinal and 38.3 ± 12.3, 35.6 ± 11.8 vs 52.2 ± 11.7%, p = 0.002 for radial strain. CONCLUSIONS: ACM pts present LV concentric hypertrophy and LV systolic and diastolic dysfunction, even in controlled disease. Altered global LV systolic function appears to be due both to longitudinal and radial dysfunction.


Subject(s)
Acromegaly/diagnostic imaging , Cardiomyopathies/diagnostic imaging , Echocardiography, Doppler , Ventricular Dysfunction, Left/diagnostic imaging , Acromegaly/epidemiology , Acromegaly/physiopathology , Adult , Cardiomyopathies/epidemiology , Cardiomyopathies/physiopathology , Female , Humans , Male , Middle Aged , Prospective Studies , Ventricular Dysfunction, Left/epidemiology , Ventricular Dysfunction, Left/physiopathology
3.
J Biotechnol ; 116(4): 347-57, 2005 Apr 06.
Article in English | MEDLINE | ID: mdl-15748761

ABSTRACT

The exo-fructosyltransferase produced from B. subtilis NCIMB 11871 strain transfers the fructose moiety from donor alpha12 linked saccharides such as sucrose, raffinose and stachyose to the acceptor d-galactose, leading to the sucrose analogue, galactosyl-fructoside. Here, we report detailed kinetic studies. The enzyme showed a remarkably high optimal temperature at 50 degrees C and was effectively immobilised on Eupergit C 250 L and Trisopor-Amino. This is also the first report about the equilibrium of the transfructosylation reaction, its activation energy determination, the structure of the product and its preparative scale isolation.


Subject(s)
Bacillus subtilis/enzymology , Fructose/chemistry , Glucose/chemistry , Hexosyltransferases/chemistry , Sucrose/analogs & derivatives , Sucrose/chemical synthesis , Bacillus subtilis/classification , Enzyme Activation , Enzyme Stability , Enzymes, Immobilized/chemistry , Species Specificity , Temperature
4.
Int J Neurosci ; 113(2): 259-77, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12751435

ABSTRACT

The present article considers a synthetical analysis of the results reported by our laboratory in the last twenty years in the field of neuroimmunomodulation. The studies we discuss here continue a previous research activity, a synthesis of which has also been published in this journal (Baciu, 1988). In that paper, we reported data concerning the role of the hypothalamic tubero-mammillary area in triggering of the phagocytic and of the secondary immune specific response. Here, we present an analysis of experimental facts gathered after 1988, and also of some prior to that date, which were not included in the above-mentioned review. They regard localizations, attained with stereotactical methods, of hypothalamic areas involved in maintenance of basal phagocytosis and of its circadian rhythm, of the phagocytic and of the primary and secondary specific response. We attempted to re-analyze these data in an integrative view, and accomplish a coherent image of the hypothalamic mechanisms of the nonspecific and specific immune response. The conclusion we draw is that the nervous system may exert its modulatory action upon the immune response in several ways: i) subsequent to a direct hypothalamic stimulation (electrical or through bacteria or bacterial products) or to a cortico-hypothalamic stimulation; ii) depending on the nature, intensity, duration, and frequency of the appropriate stimulus, it may either enhance the immune response, via neural and humoral pathways, or depress it; iii) via the hypothalamus-pituitary-adrenal axis. Nervous triggering and enhancement of the immune response are essential, their occurrence in the initial stages ensuring its favorable course. The finding that repeated electroconvulsant shocks, employed for hypothalamus stimulation in dogs of different breed, age, weight, and individual history, are followed by extremely variable changes of the phagocytic activity raises the question on the individuality of the immune response.


Subject(s)
Hypothalamus/immunology , Killer Cells, Natural/immunology , Neuroimmunomodulation/immunology , Phagocytosis/immunology , Animals , Circadian Rhythm/physiology , Guinea Pigs , Rats , Rats, Wistar , Salmonella enteritidis/immunology , Staphylococcus epidermidis/immunology
5.
Rom J Physiol ; 39-40: 3-15, 2002.
Article in English | MEDLINE | ID: mdl-15984663

ABSTRACT

The research activity upon erythropoiesis regulation carried out by the team in the Physiology Department and in the Institute of Medical Research of the Romanian Academy in Cluj-Napoca developed continuously after 1950. Our studies contributed to the isolation, identification and characterization of erythropoietin (Epo) and also to a better understanding of the nervous adaptation mechanisms to hypoxia. At present, it is well known that hypoxia acts upon erythropoiesis through Epo production. Direct central nervous stimulation through hypoxia induces, via a neuro-humoral mechanism, a sympatho-adrenal response and release of Epo. Adaptive polyglobulia as a response to hypoxia increases the capacity of oxygen binding and transport. In this paper we attempted to identify the role of the sympathetic nervous system in adaptation to hypoxia correlated with Epo secretion. Experiments were carried out in three groups of rats, respectively, with cervical, thoracic, and lumbar (without celiac) sympathectomy. The sympathectomized animals were submitted to hypobaric or to hemorrhagic hypoxia, in parallel with control groups. Erythrocytic parameters (red blood cells, reticulocytes, hematocrit, and haemoglobin) were repeatedly assayed during the following 2-4 weeks. The results showed that animals with cervical sympathectomy adapt in a deficient manner to hypoxia; lacking the adaptive sino-carotid reflexes, adaptation occurs through increased Epo secretion, animals with cervical sympathectomy having higher counts of reticulocytes and of red blood cells at the end of experiment than intact animals. Thoracic sympathectomy has little influence upon the erythrocytic response, as the largest part of the respiratory and circulatory sympathetic reactions occur via the cervical sympathetic nerve. Lumbar sympathectomy without removal of the celiac ganglion does not decrease the erythrocytic response as expected; on the contrary, the erythrocytic response is increased as compared to controls.


Subject(s)
Adaptation, Physiological , Adrenal Glands/physiopathology , Erythropoietin/biosynthesis , Hypoxia/physiopathology , Sympathetic Nervous System/physiopathology , Altitude , Animals , Blood Cell Count , Erythrocyte Count , Female , Hematocrit , Hemoglobins/metabolism , Hemorrhage/complications , Hypoxia/blood , Hypoxia/etiology , Lumbosacral Region/innervation , Male , Neck/innervation , Rats , Rats, Wistar , Reticulocytes/pathology , Sympathectomy , Thorax/innervation
6.
Rom J Physiol ; 39-40: 27-33, 2002.
Article in English | MEDLINE | ID: mdl-15984665

ABSTRACT

A good amount of experimental data suggests the existence of a circadian control of the inflammatory process. It was shown that migration of neutrophils in chemotactic gradient, ingestion of particles, vascular permeability etc. are rhythmical circadian functions. Melatonin, the pineal hormone secreted during the darkness phase, has been shown to be involved in the control of inflammation. The present study aims to assess whether neutrophil adherence to nylon fibers exhibits circadian rhythmicity and also if its amplitude and/or chronostructure are altered in a constant light regimen. Wistar rats were submitted to either an artificial light-darkness 12/12 regimen (LD) or to constant light (LL), for 15 days. Adherence of the neutrophils in whole blood was assessed at 10:00, 16:00, 22:00, and 04:00 hrs. In LD. neutrophil adherence appears to be a rhythmic, biphasic function, with the acrophase at 10:00, a secondary peak at 22:00 and trough values in the late dark hours. Constant light induces a depression of the adherence ability by about 10%, except for the 04:00 hrs point, where the value in LL is higher than in LD. The fact that adherence and phagocytic activity do not oscillate in phase suggests that the physiological relevance of neutrophil adherence goes beyond that of a first stage of the phagocytic process.


Subject(s)
Blood Cells/physiology , Light , Neutrophils/physiology , Photoperiod , Animals , Cell Adhesion/radiation effects , Circadian Rhythm , Male , Nylons , Rats , Rats, Wistar
7.
Rom J Physiol ; 39-40: 17-26, 2002.
Article in English | MEDLINE | ID: mdl-15984664

ABSTRACT

The phagocytic function was proved to be a periodic, circadian process. Its acrophase appears to be differently timed in species with different activity type, occurring in the evening in diurnal species and at night in nocturnal ones. The main pineal hormone melatonin, whose secretion occurs strictly at dark, has been shown to play a role in the control of inflammation and to exert a certain stimulatory effect upon phagocytosis in vitro. The aim of the present study was to assess whether the phagocytic activity of neutrophils in the blood of rats exhibits a circadian rhythmicity similar to that of other nocturnal rodents (mice) and also if a constant light regimen alters its amplitude and/or chronostructure. Wistar rats were submitted to either an artificial light-dark 12/12 regimen (LD) or to constant light (LL), for 15 days. In vitro phagocytosis of the neutrophils in whole blood against E.coli was assessed at 10:00, 16:00, 22:00, and 04:00 hours. In LD, phagocytosis appears to be a rhythmical function, with statistically significant differences between the highest value at 04:00 hrs and the lowest at 10:00 hrs. Constant light induces a 30% depression of the phagocytic ability throughout the whole 24 hours cycle, without altering its oscillations. The darkness period appears to play the role of a synchronizer; in its absence the rhythm tends to free-run. It may be stated that rhythmical melatonin secretion is responsible only for maintenance of the phagocytic level, probably via the anterior hypothalamic area and thymus, while it cannot account directly for the nocturnal increase of phagocytosis.


Subject(s)
Circadian Rhythm/radiation effects , Light , Phagocytosis/physiology , Photoperiod , Animals , Blood/microbiology , Escherichia coli , Male , Neutrophils/physiology , Neutrophils/radiation effects , Rats , Rats, Wistar
8.
Rom J Physiol ; 39-40: 35-41, 2002.
Article in English | MEDLINE | ID: mdl-15984666

ABSTRACT

Beginning with 1975, our group has performed some studies using an erythropoietin (EPO ) extract prepared according to an original technique from sera of anemic rabbits. Our results have contributed to the understanding of the glycoproteinic nature of this extract as well as of some of its biological features. These results were confirmed only after 1985, when recombinant EPO was obtained. The aim of this study is to emphasize some of our priorities, controversial at that time. We have shown the radioprotective effect of an EPO extract, in correlation with red cell proliferation and with an increased rate of nucleic acid metabolism and bone marrow blood flow. Consequently, we proposed the investigation of the bone marrow function using EPO. Our results are correlated with recent data obtained with recombinant EPO. They refer to the ability of EPO to prevent apoptosis, its antioxidant effects, and its ability to modulate the sympathoadrenal response to hypoxia.


Subject(s)
Erythropoietin/pharmacology , Animals , Bone Marrow/blood supply , Bone Marrow/drug effects , Bone Marrow/metabolism , Cell Proliferation/drug effects , Erythrocytes/cytology , Nucleic Acids/metabolism , Radiation-Protective Agents/pharmacology , Radiation-Sensitizing Agents/pharmacology , Regional Blood Flow/drug effects
9.
Rom J Physiol ; 37(1-4): 3-14, 2000.
Article in English | MEDLINE | ID: mdl-12413142

ABSTRACT

Ischemic hypoxia of the head induced in dogs by carotid compression produces EPO secretion, upon direct cerebral stimulation, and adaptive carotid-respiratory reflexes via sino-carotid stimulation. During hypoxic hypoxia, there also occurs extrarenal EPO production, as shown in binephrectomized rats compared to controls. Ischemic hypoxia of a single kidney transplanted in the neck area (the other kidney being removed) does not induce EPO secretion. An additional factor, of extra-renal origin, is required for the renal production of EPO in a non-hypoxic organism. Section of the spinal cord at C6 level in rats does not abolish EPO secretion induced by hypobaric hypoxia, a fact that suggests that there is no nervous center to control EPO release into a peripheral organ, but EPO might be produced in the brain itself, possibly crossing the blood-brain barrier to reach the blood flow. Stereotactical attempts to locate nervous centers of erythropoiesis regulation also failed. EPO secretion obtained by electrical stimulation of different brain areas suggests the existence of widespread secretory cells, which might be the astrocytes. EPO production along the lymph-forming territories and the involvement of the lining macrophages is reported.


Subject(s)
Brain/metabolism , Erythropoietin/biosynthesis , Hypoxia, Brain/metabolism , Animals , Kidney/metabolism
10.
Rom J Physiol ; 35(3-4): 319-23, 1998.
Article in English | MEDLINE | ID: mdl-11061331

ABSTRACT

There has been reported, in some diurnal or equivocal species (man, respectively guinea pig), a circadian rhythm of the phagocytic activity of blood neutrophils, with an acrophase occurring at the end of the light span. The present study, carried out on NMRI adult male mice kept on a LD 12:12 regimen, aimed to assess any circadian variation in the blood neutrophils' phagocytosis level. Basal phagocytic activity was tested against E. coli, every three hours of a 24 h cycle. The results show that phagocytosis in mice's blood neutrophils also presents a rhythmic circadian variation, whose acrophase is delayed with about eight hours compared to that in man, occurring in the second half of the dark period (3:00 h). The occurrence of high circadian phagocytic levels appears to be correlated with the activity type of the species and, of this point of view, mice cannot be used as a model for chronotherapeutical approaches in humans, without keeping in mind the differences between the time structure of the two species.


Subject(s)
Circadian Rhythm/immunology , Neutrophils/immunology , Phagocytosis/immunology , Animals , Male , Mice , Mice, Inbred Strains , Models, Animal , Neuroimmunomodulation/physiology , Neutrophils/cytology
11.
Rom J Physiol ; 35(3-4): 325-30, 1998.
Article in English | MEDLINE | ID: mdl-11061332

ABSTRACT

The proinflammatory cytokines tumor necrosis factor-a (TNF) and interleukin-1b (IL-1) play an important role in the pathogenesis of insulin-dependent diabetes mellitus, while TNF is also involved in promoting insulin resistance. It has been recently shown that glucose can induce the synthesis of TNF and IL-6 in human monocytes. The aim of the present study was to investigate the effect of glucose on unstimulated and lipopolysaccharide (LPS)-induced TNF and IL-1 production by human peripheral blood mononuclear cells (PBMC). No effect of glucose on spontaneous release of TNF or IL-I could be observed. The LPS-stimulated production of TNF was enhanced when cells were preincubated with increasing glucose concentrations. In contrast, no effect of glucose preincubation on LPS-induced IL-I synthesis was found. In conclusion, high glucose concentrations can increase the stimulated TNF production capacity, with possible important consequences for patients with diabetes mellitus.


Subject(s)
Diabetes Mellitus, Type 1/metabolism , Glucose/pharmacology , Leukocytes, Mononuclear/metabolism , Tumor Necrosis Factor-alpha/biosynthesis , Diabetes Mellitus, Type 1/immunology , Dose-Response Relationship, Drug , Humans , In Vitro Techniques , Interleukin-1/biosynthesis , Interleukin-1/metabolism , Interleukin-6/biosynthesis , Interleukin-6/metabolism , Leukocytes, Mononuclear/drug effects , Lipopolysaccharides/pharmacology , Tumor Necrosis Factor-alpha/metabolism
12.
Rom J Physiol ; 35(3-4): 313-8, 1998.
Article in English | MEDLINE | ID: mdl-11061330

ABSTRACT

The bilateral olfactory bulbectomy (OB) has been proposed as an animal model of depression. The present study, carried out on NMRI adult male mice kept on a natural LD 12:12 regimen, aimed to assess the influence of OB on the circadian rhythm of blood neutrophils phagocytosis. The results show that OB mice present an about 20% reduction of the basal phagocytic activity at 09.00 hrs, 15.00 hrs. and 21.00 hrs. and a 40% reduction at 03.00 hrs., leading to a flattened circadian phagocytic curve. The results indicate that bilateral olfactory bulbectomy depresses phagocytosis, alters its circadian rhythm and consequently increases susceptibility to infections.


Subject(s)
Circadian Rhythm/immunology , Neutrophils/cytology , Olfactory Bulb/immunology , Olfactory Bulb/surgery , Phagocytosis/immunology , Animals , Denervation , Functional Laterality , Male , Mice , Mice, Inbred Strains , Neuroimmunomodulation/physiology , Neutrophils/immunology , Smell/immunology
13.
Rom J Physiol ; 34(1-4): 25-33, 1997.
Article in English | MEDLINE | ID: mdl-9653807

ABSTRACT

The regulatory mechanisms of the cerebral blood flow have preoccupied the physiology department of Cluj since the end of the 4th decade. These studies continued over the last years. The researches progressed from the studies of regulation by blood pressure changes to the nervous regulation and to the metabolic one. This paper's subject is the renin-angiotensin and adrenalin system influence on the changes of cerebral blood flow during the general hypoxic hypoxia and cephalic ischemia. Experiments were performed in 10 dogs anaesthetised with a mixture of chloralose, urethan and morphine. Hypoxic hypoxia was obtained by breathing a mixture of 11% oxygen in nitrogen, in a closed system and cerebral ischemic hypoxia by partial compression of the carotid arteries, after the ligation of the vertebral and thyroid arteries. The arterial blood pressure and the cerebral and hypothalamic blood flow, measured with the heated thermoelement, were registered. The plasma renin activity was tested radioimmunologically before, at 1.5 min, 5, 10 and 15 min, after the beginning of hypoxia. In ischemic hypoxia the experiment was repeated after venous perfusion with propranolol (0.6 mg/kg/h). The systemic blood pressure increased in both forms of hypoxia. The cortical and hypothalamic blood flow increased with the systemic arterial blood pressure. The hypothalamic blood flow remained stable or diminished a little. Propranolol increased the cerebral blood flow during ischemic hypoxia up to 300%. The i.v. administration of angiotensin (1-5 mg/kg) increased the cortical flow, while the hypothalamic flow remained self-regulated. Plasma renin activity increased more in general hypoxic hypoxia, than in cephalic ischemic hypoxia. After propranolol the increase was higher in this hypoxia. Propranolol produced a major activation of the renin-angiotensin system and of the cortical blood flow in ischemic cephalic hypoxia, the renin-angiotensin system being located in the cerebral structure. As well high doses of angiotensin produced cerebral vasodilatation in small cerebral vessels. This effect was found in our experiments in the cortical blood flow too. Our results indicate a beneficial propranolol effect on cortical circulation in ischemic hypoxia.


Subject(s)
Cerebrovascular Circulation/drug effects , Hypothalamus/blood supply , Hypoxia, Brain/physiopathology , Propranolol/pharmacology , Renin-Angiotensin System/physiology , Animals , Dogs , Hypoxia, Brain/drug therapy , Renin/blood
14.
Rom J Physiol ; 34(1-4): 75-82, 1997.
Article in English | MEDLINE | ID: mdl-9653811

ABSTRACT

Previous researches of Cluj-Napoca laboratories of Physiology (Benetato, Baciu et al., 1945, 1946, 1947) demonstrated that direct electrical stimulation of the tubero-mammillary area in dogs increases, in the following hours, the blood polymorphonuclears phagocytic activity. By contrast, electrical damage of the same region produces a depression of the basal phagocytic activity and a blocking of the phagocytic response (Baciu et al., 1958, 1988). In the present research we assumed there is a stimulating effect of the arcuate nucleus, located in this area, on the phagocytic activity of blood neutrophils. We used an anodal current to stereotaxically induce lesion of the arcuate nucleus in six rats. A control group of six animals was used. Five days later, phagocytic response was induced with a Gram negative bacterial extract given i.v. The results demonstrated a decrease of the phagocytic activity from 164.31 +/- 17 bacteria engulfed by 100 neutrophils in controls, to 138 +/- 12.8 in the lesioned group p < 0.05. Phagocytic response after five hours appears depressed in the lesioned group (138 +/- 12.8 to 156.25 +/- 13.3, p < 0.05). Similar results were obtained after 24 hours. In control animals the response is very significant after 5 and 24 hrs., respectively, (p < 0.001). In conclusion, the arcuate nucleus is moderately involved in sustaining the basal phagocytic activity of blood neutrophils. It has an important role in phagocytic response.


Subject(s)
Arcuate Nucleus of Hypothalamus/physiology , Functional Laterality/physiology , Phagocytosis/physiology , Adjuvants, Immunologic/pharmacology , Animals , Bacteria , Electric Stimulation , Gram-Negative Bacteria/immunology , Neutrophils/immunology , Rats , Rats, Wistar
15.
Rom J Physiol ; 34(1-4): 95-101, 1997.
Article in English | MEDLINE | ID: mdl-9653813

ABSTRACT

Previous researches of our laboratories (1945, 1946, 1947) have shown that direct electrical stimulation of the tubero-mammillary hypothalamic area in dogs enhances the blood neutrophils phagocytic activity and the phagocytosis exhibiting leukocytes percent. After electrolytic damage of the same area, phagocytic activity decreases and phagocytic response is suppressed (1985, 1988). In the present work, we performed in mice extensive chemical lesions of the arcuate nucleus, by means of the neonatal treatment with monosodium glutamate (MSG). The experiment was carried out on 23 new-born mice. 15 mice were injected with MSG (G group), the other 8, serving as control group, received isotonic saline solution (C group). The studied parameters were, in both groups, the weight evolution of the animals, the blood neutrophils and lymphocytes percentual variation and the neutrophils' phagocytic activity, tested in vitro, expressed through the number of bacteria engulfed by 100 neutrophils and through the phagocyting neutrophils percentage. Phagocytic activity was tested in whole heparinised blood, against E. coli. Phagocytic response was elicited by i.p. injecting 0.05 ml bacterial suspension and was tested four hours later. The results show that the arcuate nucleus has little influence upon maintaining basal phagocytic activity--that does not significantly decrease after its chemical damage--, but plays a decisive role in triggering the phagocytic response. The neonatal MSG treatment also determines a decrease of the blood lymphocytes percentage and induces obesity in up to 30 days old mice pups.


Subject(s)
Arcuate Nucleus of Hypothalamus/physiology , Neutrophils/drug effects , Phagocytosis/drug effects , Sodium Glutamate/pharmacology , Animals , Escherichia coli/immunology , Lymphocytes/drug effects , Lymphocytes/immunology , Mice , Neutrophils/immunology
16.
Rom J Physiol ; 33(1-4): 75-81, 1996.
Article in English | MEDLINE | ID: mdl-9117340

ABSTRACT

The role of the thymus in maintenance of the basal phagocytosis of blood neutrophils and eliciting the phagocytic response, induced by i.v. Escherichia coli, was studied in 9 NMRI thymectomized and in 12 control mice. Thymectomy depresses the percentage of phagocyting neutrophils from 70.91 +/- 0.9 (mean +/- SEM) in controls, to 61.49 +/- 2.33 in the thymectomized rats. Phagocytic activity, as assessed by the number of bacteria engulfed by 100 neutrophils, was also lower in thymectomized mice (114.42 +/- 7.52) than in controls (163.71 +/- 4.53). A phagocytic response to i.v. Escherichia coli could nevertheless be noted in thymectomized mice, their phagocytic activity rising from the basal activity of 114.42 +/- 7.52 to 142.19 +/- 5.40 three hours after injection of Escherichia coli, while in control animals this activity rose from 163.71 +/- 4.53 to 216.46 +/- 12.91. These results may, at least partially, explain the recurrent infections and the septicemia occurring in children with Down's syndrome. It is suggested that the thymus, as an endocrine organ, may be involved in maintaining the basal phagocytic activity of blood neutrophils, while the phagocytic response is modulated by extrathymic mechanisms.


Subject(s)
Neutrophils/immunology , Phagocytosis/immunology , Thymectomy , Animals , Escherichia coli , Male , Mice , Mice, Inbred Strains , Neutrophils/cytology , Neutrophils/microbiology , Thymus Gland/cytology , Thymus Gland/immunology , Thymus Gland/surgery
17.
Rom J Physiol ; 32(1-4): 77-81, 1995.
Article in English | MEDLINE | ID: mdl-8896079

ABSTRACT

The influence of a single or several subsequent convulsant electroshocks at different time laps (2-4 day), over a month, on the phagocytic activity was studied on seven dogs. The electroconvulsant shock was performed with bitemporal electrodes, at a liminal electric power. Phagocytosis was studied in vitro with amidon particles in whole blood, incubated 1h at 37 degrees C. After 4 hours the phagocytosis increases in all animals and remains higher for 12 days. Later on the repeated shocks produce very different changes of the phagocytic activity, depending, not only on the stressor agent, but also on the animal particular reactivity, conditioned genetically and by its individual history.


Subject(s)
Electroshock , Phagocytosis/immunology , Stress, Physiological/immunology , Stress, Physiological/physiopathology , Animals , Dogs , Female , Leukocytes/physiology , Male , Time Factors
19.
Rom J Physiol ; 31(1-4): 25-45, 1994.
Article in English | MEDLINE | ID: mdl-8640365

ABSTRACT

The paper presents an integrative cybernetic model of the complex physiological process generically called "oxygen homeostasis". The model has been designed in such a manner as to enable a mathematical approach, in quantitative terms, to the various functions involved in the generation and uninterrupted functioning of the mentioned process. Those functions are: pulmonary and tissular respiratory function, blood circulation, transport, erythropoiesis, as well as other functions involved in the blood pH regulation at renal and hepatic level (the resorption of Na+ ions from the glomerular filtrate and the ammonio-genetic functions of the kidneys and, respectively, the glyco-genetic, ureo-genetic and metabolization functions of the liver). All of these functions have been assumed as regulated and controlled within a unitary cybernetic system, interpreted as an open, dynamic system. That system consists of seven multicompartment subsystems which are open and interconnected by means of exchange relations, biophysical and biochemical processes involved in the performance of the respective function. Special attention was given to the mathematical modelling of the exchange processes going on in the erythrocytic membrane as part of the transport function of the circulating blood. The mathematical description of the entire homeostatic system operation was done by means of a set of differential and algebraic equations. Some of those equations (those describing the continuity of several chemical species in a compartment of the circulatory system and those characterizing the state of thermodynamic balance of the blood subsystem within the respective compartment) enable one to determine the value of the state parameters at a given moment, as a function of the external and internal conditions and as a function of the intensity of processes specific to the subsystems considered. There are other equations (equations of regulation and control devices) that enable one to determine the variations in intensity of the processes mentioned that are necessary in order to restore the system to its "normal" state, in case of possible deregulations caused by disturbing factors.


Subject(s)
Computer Simulation , Homeostasis/physiology , Models, Biological , Oxygen/physiology , Animals , Cybernetics , Erythrocytes/physiology , Hemoglobins/physiology , Humans , Ligands , Plasma/physiology , Systems Theory
20.
Rom J Physiol ; 31(1-4): 55-8, 1994.
Article in English | MEDLINE | ID: mdl-8640368

ABSTRACT

The reticulin-M forte (R forte), an antianaphylactic peptide, extracted from organs rich in RES, previously stimulated with India ink, was analysed after acetone precipitation by paper high voltage electrophoresis. Finally the biological activity remains concentrated in the second, arbitrary group of basic peptides, fractions 1 and 3.


Subject(s)
Reticulin/analysis , Acetone , Anaphylaxis , Animals , Chemical Precipitation , Electrophoresis, Paper/methods , Female , Guinea Pigs , Indicators and Reagents , Reticulin/isolation & purification , Reticulin/pharmacology , Uterine Contraction/drug effects
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