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[Incidence of goiter and tracheal constriction among outpatients of a Munich hospital (author's transl)].

With a goiter incidence of 55%, 6.5% of the 495 patients examined showed constriction of half or more of the trachea, most frequently in the 10% of larger goiters in stages II and III. But also in the 45% of the stage I goiters occurring in the Munich ambulant patients, distinct tracheal constriction is already found, and in stage lb 9% of the stenoses involved half of the lumen. Because of the high goiter rate and the often already considerable tracheal stenoses even in the smaller goiters, the earliest possible diagnosis and treatment of small goiters with iodized salt or thyroid hormones should follow as a consequence, after exclusion of autonomic adenomata, thyrotoxicosis, cold nodules and malignant struma. The prophylaxis of struma with fully iodized salt is referred to.

Adult↗

Characterization of vascular postsynaptic neuropeptide Y receptor function and regulation. 1. NPY-induced constriction in isolated rat femoral artery rings is mediated by both Y1 and Y2 receptors: evidence from benextramine protection studies.

Neuropeptide Y (NPY), a potent pressor agent and vasoconstrictor, is thought to contribute to the sympathetically mediated postsynaptic regulation of blood pressure primarily through activation of vascular Y1 rather than Y2 NPY receptors. However, data are available that conflict with this conclusion. In this article, the relative roles of postsynaptic Y1 and Y2 receptors as mediators of direct NPY-induced isolated rat femoral artery ring vasoconstriction were evaluated through use of selective Y1 and Y2 agonists, [Leu31, Pro34]NPY ([Leu, Pro]NPY) and NPY13-36 [NPY(13-36)], respectively, and the NPY receptor antagonist benextramine (BXT). NPY, [Leu, Pro]NPY and NPY(13-36) were equipotent as vasoconstrictors, and constriction induced by each peptide, but not by the calcium channel agonist BAY K 8644 (BAY), was almost completely blocked by 10 microM BXT. Each of the three peptides also induced self- and cross-desensitization and protection from BXT blockade, except that [Leu, Pro]NPY neither desensitized nor protected NPY(13-36)-associated responses. NPY also failed to protect [Leu, Pro]NPY- and NPY(13-36)-elicited constriction, and NPY(13-36) failed to provide self-protection, from BXT blockade. However, in these instances, as opposed to the [Leu, Pro]NPY-NPY(13-36) cross-protection experiments, the occurrence of protection was probably masked by the relatively large magnitude of desensitization concurrently induced by the protecting peptide. Taken together, the present findings suggest that NPY-induced rat femoral artery vasoconstriction is mediated by separate, BXT-sensitive, postsynaptic Y1 ([Leu, Pro]NPY-activated) and Y2 [NPY(13-36)-activated] receptors.

Animals↗

[Treatment of erectile dysfunction with vacuum constriction device].

The vacuum constriction device (VCD) is a noninvasive mechanical device which may produce an erection by creating a vacuum of up to 250 mm Hg and with a rubber ring to maintain this state by constricting the base of the penis. We tested the VCD on 150 men who presented with organic and psychogenic impotence in our outpatient clinic between the years 1986 and 1992. Of the 150 men, 113 (75%) achieved an adequate erection with the VCD. However, only 72 patients agreed to buy the device and use it regularly. During follow-up of from 3 months to 5 1/2 years (mean 25 months), 65 men were using the VCD regularly and reported satisfying intercourse at least once every 2 weeks. Complications were minimal and consisted of mild numbness of the penis in 7 patients, mild cyanosis in 17, and 10 cases of painless ecchymoses and petechiae which disappeared without any treatment. From our experience, the VCD appears to be a safe, inexpensive, and easy method for impotent men to engage in sexual intercourse without, of course, eliminating other therapeutic options, including surgery.

Adult↗

Intraepineurial constriction of nerve fascicles in pronator syndrome and anterior interosseous nerve syndrome.

In PS or AINS, if obvious epineurial compression deformity of the median nerve or the AIN is not found at known sites of compression, IeCNF should be considered. IeCNF may occur in one or more nerve fascicles of the median nerve at one of multiple levels in the distal upper arm and proximal forearm. Decompression of the nerve fascicles is achieved by epineurotomy, microsurgical interfascicular dissection, and removal of the constricting outer layer of the perineurium above and below the elbow. Resection of the constricted segments of the nerve fascicles is not necessary. Intraepineurial exploration of the nerve trunk also may be considered if, after surgical decompression of PS and AINS, expected recovery has not occurred and there is no evidence of axonal degeneration.

Diagnosis, Differential↗

Selective conversion of big endothelins to tracheal smooth muscle-constricting 31-amino acid-length endothelins by chymase from human mast cells.

Chymase from human mast cells selectively cleaved big endothelins (ETs) at the Tyr31-Gly32 bond and produced novel trachea-constricting 31-amino acid-length endothelins, ETs(1-31), without any further degradation products. Chymases from other species, such as the enzymes from rat connective tissue and mucosal mast cells, and the other chymotrypsin-like proteases examined degraded big ETs. ETs(1-31) exhibited various contractile potencies as to the rat trachea in comparison with 21-amino acid-length endothelins, ETs(1-21), and big ETs: ET-1(1-21) > ET-1(1-31) > big ET-1; ET-2(1-31) > ET-2(1-21) > or = big ET-2; ET-3(1-21) > or = ET-3(1-31) > or = big ET-3. Among the ETs(1-31), ET-2(1-31) was the most potent constrictor, its potency being similar to that of ET-1(1-21) and stronger than that of ET-2(1-21). The contractile activity of ETs(1-31) may not be the consequence of conversion to the corresponding ETs(1-21) by phosphoramidon-sensitive ET-converting enzymes or other chymotrypsin-type proteases and metalloendopeptidases, because the contractile activity was not inhibited significantly on treatment with inhibitors of these proteases before the addition of ET-1(1-31). Inhibitors of chymotrypsin-type serine proteases, on the contrary, significantly enhanced the contractile activity exhibited by ET-1(1-31) and big ET-1, but not that by ET-1(1-21). These results suggest that protease(s) on the surface of the rat trachea tends to degrade ETs(1-31) and big ETs, and thereby reduces their contractile activity. Taken together, the results suggest that trachea-constricting ETs(1-31) generated by human chymase may play a role in the hyper-responsive airway in allergic inflammation.

Animals↗

Airway and lung tissue behaviour during endothelin-1 induced constriction in rats: effects of receptor antagonists.

Endothelin (ET) 1, a 21 amino acid constrictor peptide, is one of the most potent agonists of airway smooth muscle and acts on two different receptors, i.e., ETA and ETB receptors. Recently, it has been shown that there are species and organ differences in physiological roles of each ET receptor. In rats, however, the physiological roles of ET receptors remain to be clarified. We questioned whether ET-1 might affect airway and lung tissue via different ET receptor subtypes in rats. To answer this question, we investigated the effects of ET-1 on lung behaviour in anesthetized, open-chested, mechanically ventilated (f = 1 Hz, VT = 9 mL/kg, PEEP = 3 cmH2O (1 cmH2O = 98.1 Pa)) rats in the absence or the presence of ETA and ETB selective antagonists, i.e., BQ-123 and BQ-788, respectively. Using alveolar capsules, we calculated lung elastance (EL), resistance of lung (RL), tissue (Rti), and airway (Raw), and hysteresivity (eta = 2 pifRti/EL) under control conditions and after intravenous administration of ET-1 (10(-8) mol/kg). ET-1 induced significant increases in RL, Rti, Raw, EL, and eta. BQ-123 did not affect ET-1 induced constriction, while BQ-788 significantly reduced delta RL, delta Rti, delta Raw, delta EL during ET-1 induced constriction. The effects of the combination of BQ-123 and BQ-788 were not different compared with BQ-788. Eta was not affected by BQ-123 and BQ-788. These data suggest that ETB, but not ETA, receptors may have significant physiological roles in rat lungs in response to ET-1.

Airway Resistance↗

Coexistence of vessel enlargement and paradoxical constriction in a diseased left anterior descending artery: an in vivo assessment using a new system for quantitative analysis of intracoronary ultrasound.

Previous studies based on conventional two-dimensional intravascular ultrasound revealed that coronary arteries can undergo either vessel enlargement and paradoxical constriction in response to plaque growth. We report a case in which the occurrence of vessel enlargement and paradoxical constriction was documented in the same coronary artery (left anterior descending). A multiple cross-section analysis was performed, using a novel 3-D system of reconstruction of IVUS images, which provides a large number of cross-sections within the reconstructed segments.

Cardiomegaly↗

An assessment of a vacuum constriction device in treating erectile dysfunction.

Male erectile dysfunction is a common health concern, affecting an estimated 15 million men between the ages of 18 to 59. A vacuum constriction device, a mechanical apparatus using vacuum pressure to draw blood into the erectile tissue of the penis and a constriction ring worn at the base of the erect penis to maintain the erection during intercourse, is a highly efficacious treatment when combined with an instructional protocol and systematic followup program.

Adolescent↗

Chronic constrictive pericarditis. A case report and review of the literature.

Actinomycosis is typically a chronic infection of the cervicofascial, thoracic, or abdominal region. Involvement of the heart occurs but is unusual. We present a case of chronic constrictive pericarditis caused by actinomycetes. The actinomycosis infection was present for 20 years, thereby representing the longest duration reported in the literature, to our knowledge.

Actinomycosis↗

Constrictive pericarditis in children.

We observed five cases of constrictive pericarditis (CP) during a 12-year period, and studied the clinical findings, usual causes, and hemodynamic findings. There are two variants of CP: a chronic form, which is usually of unknown cause, and a rapidly developing form, which follows an attack of effusive pericarditis. A high index of suspicion is necessary to establish the diagnosis of CP both in children with a prolonged course of ascites and failure to thrive and in children with effusive, usually purulent, pericarditis. Although CP is rare in childhood, it should be easily recognized and curative surgical therapy should be rapidly initiated.

Adolescent↗

Cerebral cortical dysplasia and digital constriction rings in Adams-Oliver syndrome.

Adams-Oliver syndrome (AOS) is characterised by aplasia cutis congenita of the scalp and variable degrees of terminal transverse limb defects. Short fingers and hypoplastic nails also occur in this predominantly autosomal dominant syndrome which displays marked variability of expression and lack of penetrance in some cases. We describe a boy with AOS whose sister is also mildly affected. Their mother has hypoplastic fifth toenails which may represent very mild expression of the syndrome. Brain (computed tomography) imaging to investigate mild left hemiparesis in the boy demonstrated severe cortical dysplasia of central, occipital and anterior regions of the right cerebral hemisphere. A variety of brain and cranial malformations has been reported in AOS but dysplasia of the cerebral cortex has not been noted previously. In addition, the boy and his sister have apparent constriction rings present on the toes which are uncommon in AOS.

Cerebral Cortex↗

Psoralen and long wavelength ultraviolet radiation as an adjuvant therapy for prevention of intimal hyperplasia and constrictive remodeling after balloon dilation: a study in the rabbit iliac artery.

BACKGROUND AND OBJECTIVE: Restenosis after balloon angioplasty is the summated effect of intimal hyperplasia and arterial shrinkage, both caused by hyperproliferation. In the present study, the potential of a photochemotherapeutic modality (Psoralen + UVA: PUVA) for the prevention of angioplasty induced proliferation was explored. STUDY DESIGN/MATERIALS AND METHODS: In rabbit iliac arteries, balloon dilation followed by PUVA-therapy (H = 1 J/cm2) was performed (n = 15). Contralateral arteries served as control. After 2 and 28 days of survival, the contribution of intimal hyperplasia and remodeling to lumen loss was determined by means of angiography and histological analysis. RESULTS: After 2 days, large parts of the media had become acellular, while proliferation was occurring predominantly in the adventitia in both groups. After 28 days, late loss, arterial shrinkage, but not intimal hyperplasia were larger in the PUVA group (P < 0.05). CONCLUSION: PUVA-therapy did not prevent intimal hyperplasia following balloon dilation but enhanced luminal narrowing by augmented constrictive remodeling.

Analysis of Variance↗

Doppler sonographic diagnosis of severe portal vein pulsatility in constrictive pericarditis: flow normalization after pericardiectomy.

This case report describes the noninvasive assessment of hepatic and portal vein hemodynamics in a patient with constrictive pericarditis before and after pericardiectomy. Doppler sonography of the hepatic veins demonstrated a typical W-shaped pattern with pronounced late diastolic flow reversal that disappeared after surgery. Preoperatively, we observed severe pulsatility of the portal vein with flow reversal in systole; after pericardiectomy, portal venous flow was normal. We concluded that the high right atrial pressure in this patient might have led to increased hepatic venous outflow resistance, with subsequent trans-sinusoidal shunting between the hepatic artery and portal vein causing severe portal vein pulsatility. After pericardiectomy and a decrease in right atrial pressure, portal vein flow normalized.

Adolescent↗

Characteristics of coronary flow velocity in constrictive pericarditis.

A 50-yr-old man developed constrictive pericarditis following an episode of acute pericarditis. Cardiac catheterization revealed a typical early diastolic dip and plateau configuration in both the right and left ventricular pressure curves. The coronary flow velocity pattern determined using an intracoronary Doppler guidewire showed an abrupt decrease in peak velocity at early diastole and followed by plateau until late diastole, the so-called dip and plateau configuration. After a successful pericardiectomy, cardiac catheterization no longer showed the dip and plateau configuration, but the early diastolic dip in the coronary flow velocity persisted probably because of infiltration of the organic involvement into the myocardium.

Blood Flow Velocity↗

Hemodynamic profile of constrictive pericarditis produced by a massive right pleural effusion.

We report a 29-year-old female who presented with thyrotoxicosis and a massive right pleural effusion. Cardiac catheterization in the presence of the effusion revealed equalization of abnormally elevated right and left heart filling pressures. Repeat study after thoracentesis demonstrated normal intracardiac pressures, which were unchanged by volume loading with normal saline. This case report suggests that both extrinsic cardiac chamber compression produced by the large unilateral effusion and ventricular interdependence altered diastolic function of the right and left ventricle in a manner resembling constrictive pericarditis or restrictive cardiomyopathy.

Adult↗

Pulmonary venous flow in constrictive pericarditis.

A 35-year-old white female patient presented with radiation-induced constrictive pericarditis. Intraoperative transesophageal echocardiography revealed a uniphasic diastolic flow pattern. This pulmonary flow pattern reverted to a normal biphasic systolic/diastolic profile immediately following radical pericardiectomy. This abnormal flow pattern was previously described as typical for restrictive cardiomyopathy. However, in this case it is most likely due to a marked decrease in left atrial compliance induced by the thick fibrous scar encasing the atrial.

Adult↗

Fos expression in the medullary dorsal horn of the rat after chronic constriction injury to the infraorbital nerve.

Chronic constriction injury to the rat's infraorbital nerve (IoN-CCI) induces asymmetric face grooming directed to the injured nerve territory and, beginning at 7-12 days postoperative, hyperresponsiveness to mechanical stimulation in this territory (B.P. Vos, A.M. Strassman, and R.J. Maciewicz, 1994, J. Neurosci. 14:2708-2723). To examine central mechanisms involved in these behavioral alterations, changes in nonevoked and mechanical stimulation-evoked fos-like immunoreactivity (fos-LI) following IoN-CCI were quantified in the medullary dorsal horn. Following the appearance of hyperresponsiveness in IoN-CCI rats, experimental and matched sham-operated rats were anesthetized with urethane and received either no stimulation or repeated stimulation with either a 2- or 15-g von Frey hair applied to the hairy skin between vibrissae B3-4/C3-4 on the operated side. Unstimulated IoN-CCI rats had increased fos-LI in laminae I-IV of the ipsilateral medullary dorsal horn. In both groups, mechanical stimulation produced a distinct pattern of fos-LI in the ipsilateral medullary dorsal horn, the quantity of which was related to stimulus intensity. For both stimulus intensities, the total amount and the rostrocaudal spread of evoked fos-LI were significantly larger in IoN-CCI rats. In IoN-CCI rats, stimulation-evoked increases in fos-LI were proportionally larger in laminae I-II than in III-IV. This laminar effect was also present in sham-operated rats but only for 15-g stimulation. Neither condition nor stimulus intensity affected fos-LI in the contralateral medullary dorsal horn. Positive correlations were found between the behavioral parameters of increased trigeminal nociceptive activity and the total amount of fos-LI in the ipsilateral medullary dorsal horn. The results demonstrate that IoN-CCI induces significant alterations in the central processing of afferent signals, which may underlie behavioral manifestations of increased nociceptive activity.

Analysis of Variance↗

Fetal limb constriction: a possible complication of CVS.

A case of fetal loss due to infection after first-trimester chorionic villus sampling is described. The fetus was born at 18 3/7 weeks and showed an annular constriction of one of the arms as seen in the amniotic band sequence. Induction of congenital defects might be one of the complications of chorionic villus sampling.

Abortion, Incomplete↗