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At least 829 records · Page 46Linked to original sources
PubMed1999

An unusual presentation of constriction band syndrome.

Congenital constriction band syndrome is a rare entity with a wide spectrum of associated congenital anomalies. Review of the pathogenesis and an unusual case of constriction band syndrome in a newborn are presented. Surgical excision of the deformity and the band was performed within the first week of life. There were no vascular or neural structures within the excised tissue, and there were no other associated anomalies other than dextrocardia and an equinovarus deformity of the foot. The wound was closed primarily without the need for Z-plasties. This alternative method of treatment can be considered in such unusual locations of constriction band syndromes.

Amniotic Band Syndrome↗
PubMed1976

[Permanent jaw constriction of extra-articular origin].

The authors describe a new case of permanent constriction of extra-articular osseous origin. They consider the classical distinction between constrictions due to traumatism and those due to malformation (O. Jacob's disease) debatable, for this malformation is usually secondary to traumatism. They also think that the osteoma responsible for constriction may be considered a localisation of neurogenic para-osteoarthropathies.

Adult↗
PubMed2000

Effects of TMB-8 on constriction of pial arteries in rats.

AIM: To study the effects of 8-(N,N-diethylamino)-n-octyl-3,4,5-trimethoxybenzoate (TMB-8) on constriction of pial arteries (PA). METHODS: The change of PA in rats was observed continuously and directly through cranial window using microcircular image-shearing system. RESULTS: Nimodipine (Nim) 1 mumol.L-1 produced dilatation of PA immediately and the maximal response occurred in 2 min. But the diameter was not changed by TMB-8 50 mumol.L-1. PA diameter decreased immediately after the application of CSF containing KCl. TMB-8 25, 50 mumol.L-1 apparently inhibited KCl-induced PA constriction. When persistent constriction was evoked by 5-HT, diameter of PA were increased in a concentration-dependent manner after application of TMB-8, which was inhibited by N omega-nitro-L-arginine methyl ester (L-NAME). CONCLUSION: TMB-8 inhibited the contraction induced by 5-HT or KCl in cerebral artery, probably via its calcium antagonization and nitric oxide release.

Animals↗
PubMed2000

[Surgical treatment of congenital clubfoot with constriction band syndrome].

Twelve feet in 11 patients with constriction band syndrome age ranging from 3 to 18 months (mean age 11 months) were evaluated in this study. The constriction band was located at the in the calf, at distal, media and proximal third levels. All these patients were treated surgically by a wide peritalar release using the Cincinnati incision, followed by a two-stage Z-skin plasty. Both clinical and radiological results were evaluated. In our material an excellent result was achieved in 1 case, good results in 3 cases, satisfactory in 4 cases and poor in the remaining four cases. Very good and good results were achieved in feet with shallow bands type II and III, while poor results were found in feet with deep constriction band type I. Early surgical treatment followed by serial casting leads to better functional results.

Amniotic Band Syndrome↗
PubMed2000

[Distraction osteogenesis for correction of maxillary constriction].

OBJECTIVE: To study the methods and effects of distraction osteogenesis for correction of maxillary constriction. METHODS: 10 cases (5 males, and 5 females, aged 16-33 years, average 19.6) were treated by distraction osteogenesis for correction of maxillary constriction. Le Fort I osteotomy and palatal suture osteotomy for the upper jaw were made before opening of the Hyrax screw expander. Totally four times of opening the screw a day were performed. 2 cases were expanded unilaterally. The AP head films were analyzed using Image and Database Analysis System (IDAS) before and after expansion. RESULTS: 1. Expansion of upper arch was achieved done within a few days, and the maxilla, maxillary dental base and the posterior teeth were expanded as much as 3.84 mm, 3.25 mm, and 5.61 mm respectively. 2. The new bone was formed between the opened suture in two weeks, and filled the suture in 2 to 3 months. 3. Maxillary teeth tipped bucally a little bit. CONCLUSIONS: Distraction osteogenesis rapid maxillary expansion could get a good result following Le Fort I and palatal suture osteotomy for correction of maxillary constriction.

Adolescent↗
PubMed2002

A 3D unsteady flow analysis in a doubly constricted arterial vessel.

The aim of this study is to examine the interaction between two mild atherosclerotic proliferations spaced apart by a distance S by analyzing their influence on flow structure, pressure drop and stress field in an arterial vessel under pulsatile flow conditions. This has been achieved numerically by employing a time accurate, cell centered finite volume method in solving the Navier-Stokes equations governing the 3D unsteady flow dynamics in a conceptual model of an multiply constricted arterial vessel. In comparison to the pressure drop across a single stenosis, nearly a 50% increase in the late systolic and early diastolic pressure drops has been observed across the two mild constrictions when they are spaced within a distance of S<or=4. When S<or=4, more than a 25% reduction in the peak systolic wall shear stress (WSS) on the downstream constriction is noted.

Arteries↗
PubMed2004

[Constricted ear therapy with free auricular composite grafts].

OBJECTIVE: A simple and effective therapy for single side constricted ear. METHODS: Transplanting normal side free composite auricular grafts to constricted ear (15 patients and 15 sides), then lengthening the helix, exposing the scapha, correcting deformity. RESULTS: The 15 patients composite grafts all survived. The helix has been lengthened, the scapha exposed, the normal ear reduced, the constricted ear augmented and two sides ear have become symmetry. CONCLUSION: This method is simple and results are satisfied.

Adolescent↗
PubMed2005

Effects of hyperbaric oxygen on skin blood flow and tissue morphology following sciatic nerve constriction.

BACKGROUND: Constriction of the sciatic nerve by loose ligation produces an inflammatory neuropathic injury. This represents an animal model for peripheral mononeuropathy. Oxygen-derived free radicals are suspected to play an important role in the pathogenesis of ischemia/reperfusion injury, leading to neurogenic inflammation. Hyperbaric oxygen (HBO) has been used anecdotally to treat clinically similar conditions in humans, but specific effects on the animal model have not been well studied. OBJECTIVE: This study in a rat model examined the effects of hyperbaric oxygen on skin blood flow and tissue morphology by light and electron microscopy following sciatic nerve constriction. DESIGN: A scientific investigation in a rat model. METHODS: In this study, the neuropathic injury was established by loose ligation of the rat sciatic nerve. The animals were divided into three groups, sham (S, n=8), ligation but no treatment (LN, n=8) and ligation and treatment with hyperbaric oxygen (LT, n=8). The treatment group (n=8) received hyperbaric oxygen treatment immediately following the injury and daily for four additional days at the same time interval. One hundred percent O2 at 3 atmospheres absolute pressure (66 feet sea water) was administered for two hours. The hindpaws of the rats were observed by light microscopy, electron microscopy, laser Doppler flowmetry (LDF), and clinically for the presence of edema. RESULTS: Untreated animals demonstrated marked tissue edema following sciatic constriction, whereas animals that received hyperbaric oxygen had minimal to no edema. The sham group demonstrated normal histology. The group not treated with hyperbaric oxygen demonstrated swollen mitochondria (2-3 times), with loss of cellular integrity, multiple vacuole formation in both nerve and muscle tissue, widened sarcomeres in muscle, and degenerative changes in the nerve myelin sheaths. The group treated with hyperbaric oxygen demonstrated preservation of cellular structure including mitochondrial integrity, no vacuole formation, and maintenance of normal, easily identifiable nerve structure. The sham group had no change of skin blood flow. Skin blood flow of LT group was decreased immediately after ligation (p<0.05) and recovered to baseline level before ligation on Day 5 after four hyperbaric oxygen treatments. Skin blood flow of LN group was decreased immediately after ligation (p <0.01) and did not recover (p <0.01). CONCLUSION: This study evaluated tissue changes after nerve injury caused by loose ligation of the sciatic nerve in rats. Hyperbaric oxygen treatment following sciatic nerve injury reduced tissue edema, improved skin blood flow, and preserved muscle and neuronal ultrastructural integrity.

Journal Article↗
PubMed1990

[Mammalian pupil constriction to light in the presence of atropine in hamster. Part I. Hamster and visual rays].

Mammalian pupils constrict in reaction to lights. Miosis occurs via afferent and efferent nerves. Therefore, once the pupil is pretreated with atropine, miosis no longer occurs, even when the retina is intact. We found that hamster pupil constricts in reaction to light in the presence of atropine. We examined the relationship with pupillary size, light intensity, wavelength and intervals of darkness. Pupillary constriction was found when the retina was withdrawn, and the miosis was not affected by autonomic blocking agents, capsaicin pretreatment and tetrodotoxin, a nerve blocking agent. Hamster pupil reacts to lights (visible rays-ultraviolet) in the presence of atropine and in the absence of retinal function.

Animals↗
PubMed1988

Acetylcholine produces cerebrovascular constriction through activation of muscarinic-1 receptors in the newborn pig.

This study was designed to characterize the nature of responses to selective muscarinic (M)-1 and M-2 agonists and to determine the receptor subtype which mediates the vascular response to acetylcholine in the cerebral circulation of the newborn pig. Pial arterioles of anesthetized newborn pigs were observed using the closed cranial window method. Topical McN-A-343 (10(-7), 10(-4) M), an M-1 agonist, produced pial arteriolar constriction (diameters were 140 +/- 8, 127 +/- 9 and 111 +/- 8 microns for control, 10(-7) and 10(-4) M McN-A-343) that was blocked by topical pirenzepine (10(-3) M), an M-1 antagonist. Topical bethanachol (10(-7), 10(-4) M), an M-2 agonist, produced pial arteriolar dilation (diameters were 148 +/- 8, 169 +/- 10 and 181 +/- 10 microns for control, 10(-7) and 10(-4) M bethanachol) that was blocked by 4-DAMP 4-diphenylacetoxy-N'-methylpiperidine methiodide (10(-3) M), an M-2 antagonist. Responses to McN-A-343 were unchanged after 4-DAMP, and responses to bethanachol were unchanged after pirenzepine. Topical McN-A-343 and bethanachol elicited modest increases in cortical periarachnoid cerebrospinal fluid levels of 6-keto-prostaglandin F1 alpha, prostaglandin E2, thromboxane B2 and prostaglandin F2 alpha. Topical acetylcholine (10(-7), 10(-4) M) elicited pial arteriolar constriction and large increases in cerebrospinal fluid prostanoid levels which were blocked by atropine (0.5 mg/kg i.v.) and topical pirenzepine (10(-3) M), but not by topical 4-DAMP. These data demonstrate the existence of M-1 and M-2 receptors in the cerebral circulation of the newborn pig and indicate that acetylcholine elicits cerebrovascular constriction and increased cerebrospinal fluid prostanoid synthesis via activation of M-1 receptors.

(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethy↗
PubMed1989

[Complications of rheumatoid pericarditis: constriction and tamponade].

Pericarditis is frequent in patients with rheumatoid arthritis. It is usually asymptomatic, but cases of constrictive pericarditis or, more rarely, tamponade have been reported. In such cases, the study of pericardial fluid is of special interest for the aetiological diagnosis. Early medical treatment with or without pericardiocentesis is effective in most cases of tamponade, but constrictive pericarditis demands pericardiectomy. We report here three cases of pericarditis responsible for cardiac compression: two cases of tamponade and one case of constrictive pericarditis.

Adult↗
PubMed1987

Inhibition of constriction of cerebral arterioles in vivo by naftidrofuryl. Action against serotonin and dinoprost.

The effect of 2-(diethylamino) ethyl-tetrahydro-alpha-(1-naphthyl-methyl)-2-furanpropionate (naftidrofuryl, Praxilene) on an in vivo preparation of mouse cerebral blood vessels was investigated. Naftidrofuryl significantly reduced the arteriolar constriction produced by topical application of serotonin or dinoprost (prostaglandin F2 alpha). Local application of 10(-5) mol/l naftidrofuryl reduced both the constrictions to serotonin or dinoprost, when applied simultaneously with either constrictor. However, 10(-7) mol/l naftidrofuryl only inhibited serotonin. Moreover, 30 min after intraperitoneal injection, 160 mg/kg naftidrofuryl inhibited constrictions by either serotonin or dinoprost but 40 mg/kg only inhibited serotonin. 10 mg/kg also inhibited serotonin. The results are compatible with reports of a relatively selective action of naftidrofuryl on the serotonin S2 receptor. Moreover, while naftidrofuryl has long been suggested as a drug which could enhance cerebral blood flow or improve cerebral ischemia, the present observations suggest an antispasmodic effect on cerebral vessels in vivo.

Animals↗
PubMed1979

Annular constricting bands.

We reviewed forty-five patients with congenital constriction bands with an average follow-up of 15.8 years. The family history and associated anomalies were recorded and particular attention was paid to temperature gradients and neurocirculatory deficits with respect to band location. No family history of band constrictions was elicited. Most of our patients were products of first pregnancies and of young mothers. Deformity of the nails was a constant finding in patients with distally located bands. All patients demonstrated at least one other anomaly, most commonly a malformation of the hand. Neural deficits were noted in 23 per cent of the patients, while circulatory findings appeared in 16 per cent. A significant temperature gradient averaging 2.38 degrees Celsius was noted in twenty patients in whom the bands were located proximally. All patients with neural deficits demonstrated a significant temperature gradient. Staged z-plasty was the procedure of choice in surgical release of constriction bands.

Abnormalities, Multiple↗
PubMed1985

Effects of calcium entry blockers on coronary constriction and myocardial ischemia due to leukotriene D4.

Recent studies show that leukotrienes (LTs) produce profound coronary artery constriction. Although calcium entry blockers are commonly used to remedy coronary vasospasm, their capacity to interfere with LT-mediated coronary constriction is unknown. Therefore, we compared effects of intracoronary LTD4 before and during treatment with calcium entry blockers in the in situ, blood-perfused hearts of domestic pigs. Intravenous administration of verapamil (0.1-1.6 mg/kg), nifedipine (10 or 100 micrograms/kg) or diltiazem (0.6-2.0 mg/kg) sufficient to increase base-line coronary blood flow (CBF) and decrease mean arterial pressure did not change decrement in CBF after LTD4. Infusion of verapamil (0.01-0.04 mg/min) into the left anterior descending coronary artery raised pre-LTD4 CBF almost 2-fold without alteration in mean arterial pressure, heart rate or left ventricular end-diastolic pressure. Intracoronary boluses of LTD4 (0.3, 1.0 and 3.0 micrograms) during verapamil infusion into the same vessel caused dose-dependent decreases in CBF identical to those observed when LTD4 was injected during control infusion. ECGs showed myocardial ischemia during severe flow reduction after high dose intracoronary LTD4 (3.0 or 10.0 micrograms). When the same LTD4 doses were injected during intracoronary verapamil, electrocardiographic changes did not occur despite similar decreases in CBF. The capacity of verapamil to prevent LTD4-induced ischemia may be caused by higher residual CBF after LTD4 even though the magnitude of LTD4-induced CBF decrement was unaltered. LTD4-induced coronary constriction seems to be mediated by a mechanism unrelated to calcium entry channels blocked by verapamil, nifedipine or diltiazem.

Animals↗
PubMed1972

Investigations on the neural control of respiration in experimental constriction of the upper airways.

The adaptation of the work of the respiratory centers to suddenly arising respiratory resistance has been the object of interest of numerous investigators. Some of them believed that in this condition an essential role is played by the vagus nerves. Others considered that neurocontrol is mainly dependent on the respiratory muscles. The present study was undertaken to establish which of these two systems is the preponderantly responsible one. Experiments were made with anesthetized intact and vagotomized rabbits. Constriction of the airways was achieved by connecting narrowed glass tube to the trachea. The activity of the respiratory centers was evaluated on the basis of their main two "outputs", the activity of phrenic neurons and of the respiratory motoneurons of the vagus nerve. In intact animals as a response to constriction a decrease of the respiratory frequency and an immediate increase of neural activity were observed. An increased activity of motoneurons was also noted in vagotomized animals, however, after a latency period lasting about 15 sec. The respiratory frequency in these animals changed in the opposite direction becoming higher after 15 sec. Results indicate that the vagus nerves play an essential role in the adaptation of the respiratory centers to constriction. All other sources and ways of information may compensate respiratory resistance by intensifying the work of the respiratory muscles only after the lapse of a certain time, moreover, they are incapable of adjusting an optimal rhythm. The possible sources of information in these conditions are discussed.

Adaptation, Physiological↗
PubMed1983

Constriction of fetal ductus arteriosus by nonsteroidal antiinflammatory drugs.

Transplacental fetal ductal constriction was studied for 24 NSAIDs in full-term pregnant rats. All 16 acidic NSAIDs constricted the fetal ductus, but considerable differences in the grade of effect were noticed with the clinical doses of each NSAID. Six of the eight basic NSAIDs did not constrict the fetal ductus. It is concluded that acidic NSAIDs should not be administered to pregnant women. However, it may be established in the future that some basic NSAIDs can be administered safely.

Animals↗
PubMed1983

Effect of drugs used in obstetrics on the constriction by oxygen of the ductus arteriosus of the rabbit fetus.

The tone of the ductus arteriosus of the rabbit fetus near term constricted by oxygen (PO2 = 20 kPa) was relaxed reversibly by the drugs chlorpromazine, promethazine, drotaverine, papaverine, diazepam, propanidid, isoxsuprine, pethidine, 5-ethyl-5-(1-methyl-propyl) 2-thiobarbituric acid, and furosemide. Ethyl alcohol, on the other hand, caused constriction of the fetal ductus arteriosus. These drugs if used in obstetrics may disturb the newborn's adaptation to extrauterine life by inhibiting the postnatal closure of the ductus arteriosus. On the other hand, the constrictive effect of alcohol may adversely affect the fetus. The results make it necessary to investigate the effect of the drugs applied during the perinatal period on the adaptation of newborns to extrauterine life.

Animals↗
PubMed1994

Constrictive pericarditis after sclerosing therapy with mitomycin C for malignant pericardial effusion: report of a case.

Malignant pericardial effusion with cardiac tamponade is a life-threatening oncological emergency. Pericardiocentesis with sclerosing therapy is a life-saving palliative treatment procedure. Because of the short life expectancy in these patients, pericardial constriction after pericardial sclerosing therapy has been rarely reported in the literature. We report a patient with malignant pericardial effusion and cardiac tamponade which was successfully controlled by intrapericardial mitomycin C instillation. This patient developed pericardial constriction six months after mitomycin C pericardial sclerosis. It should be noted that pericardial constriction may occur if a patient survives long enough after successful pericardial sclerosis.

Cardiac Tamponade↗