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Biomedical subjects

A Wilhelm

Publications and source records attributed to A Wilhelm.

At least 37 records · Page 2Linked to original sources
PubMed1997

Stenosis of the subclavian vein. An unknown cause of resistant reflex sympathetic dystrophy.

The striking similarity of certain pain symptoms and neurologic changes in RSD and the findings of severe thoracic outlet and inlet syndrome were the reason why clinical diagnostic studies of this dystrophy were also completed by radiologic examinations of the vessel system. Surprisingly, more or less striking and differently configurated stenoses in the area of the subclavian vein, with a resulting impairment of the venous run-off, were found. Those findings have been documented in 20 of 21 patients with RSD since 1984 by functional venography and, in the meantime, they were confirmed intraoperatively in nine resistant cases. The stenoses led to a lesion-caused disproportion between increased arterial inflow and decreased venous outflow, with venous stasis. Consequently, they acted as a primary cause of an edema of the hand, with corresponding regional results, mainly on the function of the sympathetic nervous system. That shows a primarily increased activity in RSD that under the influence of local factors results in a pathologic positive feedback mechanism, as already was known. The stenosis of the subclavian vein, in my opinion, is the long-searched for cause of the so-called "individual predisposition." The use of functional venogram in diagnosis is essential because it gives important hints at the diagnostic and prognostic outlook for a possible surgical treatment of resistant RSD. It is also very important in understanding the pathogenesis. To improve the venous flow and diminish or interrupt the sympathetic efferences, we performed transaxillary decompression of the neurovascular bundle with additional upper thoracic sympathectomy in resistant cases of RSD. Nine patients experienced immediate improvement of the pain syndrome and edema, as well as the entire postoperative course. After an average follow-up of 7.5 years, we found an excellent result in seven patients, a good result in one, and a fair result in one. Intraoperative findings and the arteriograms we performed on seven surgically treated patients indicate the primarily increased sympathetic activity in RSD is mainly caused by irritations and compressions of the lower plexus roots as well as the postganglionic fibers in the area of the subclavian artery, mainly by the inner rim of the first rib and fibromuscular structures. So the two main pathogenetic factors of RSD are known, and now can be localized and documented radiologically. It now should be possible to study the pathophysiology of RSD in an appropriate animal model.

Adult↗
PubMed1996

Tennis elbow: treatment of resistant cases by denervation.

Anatomical and clinical research has shown that the entire lateral epicondylar region is innervated only by radial nerve branches. Based on these investigations we have developed a surgical procedure for complete denervation which is indicated only in resistant cases of tennis elbow. Only one nerve pathway calls for careful exposure, otherwise denervation is accomplished blindly by disinsertion of certain muscles. The result of this procedure also depends on simultaneous indirect decompression of the posterior interosseous nerve. Excellent or good results were obtained in 90% on average. Results of denervation did not improve by additional direct radial nerve release.

Adult↗
PubMed1996

Influence of dextrans on lung preservation: is the molecular weight important?

BACKGROUND: The addition of dextran with a molecular weight of 40,000 Dalton in pulmonary preservation solutions has proved to be beneficial. However, dextrans of other size have not yet been investigated. Therefore, it is unclear whether dextran 40,000 represents the optimal additive for lung preservation solutions. METHOD: In a working rat heart-lung model, lung were preserved with regular Euro-Collins solution or with Euro-Collins solution containing 5% dextran of different sizes: 40,000 Dalton molecular weight; 70,000 Dalton molecular weight; 160,000 Dalton molecular weight. After 2 hours of ischemia functional (oxygenation; pulmonary vascular resistance) and structural (wet/dry-ratio, light microscopy) data were assessed and the amount of dextran in the lung tissue was measured. RESULTS: Lungs preserved with Euro-Collins solution 70,000 Dalton molecular weight or Euro-Collins solution 160,000 Dalton molecular weight exhibited superior functional and structural results when compared with Euro-Collins solution and Euro-Collins solution 40,000 Dalton molecular weight. Additionally, the least amount of dextran in the lung tissue was found in organs preserved with Euro-Collins solution 160,000 Dalton molecular weight after ischemia and reperfusion. CONCLUSIONS: Dextrans are useful additives for lung preservation solutions. However, the size of the molecules is important because dextrans of 160,000 Dalton molecular weight were superior to dextrans of lower molecular weight in our study.

Animals↗
PubMed1994

Release of chemoattractants and neutrophil activation in acute myocardial infarction immediately after successful recanalization of the infarct-related vessel by angioplasty.

The study investigated inflammatory responses in evolving myocardial infarction. Fifteen patients with acute myocardial infarction, who had undergone balloon recanalization of the infarct-related coronary artery within 4 h after onset of symptoms, were examined. Blood samples were obtained through the guiding catheter and from the pulmonary artery before and immediately after successful recanalization. After recanalization, plasma from the pulmonary artery was 47% (quartiles: 19%, 78%; P = 0.001) more chemotactic to neutrophils from normal donors than before recanalization. Furthermore, significant changes in neutrophil function were found in the pulmonary artery. Compared to the values before recanalization, the nitroblue tetrazolium score rose by 31% (quartiles: 4%, 37%; P = 0.003), FMLP-stimulated superoxide anion production by 10% (quartiles: 0%, 39%; P = 0.020), and chemotaxis by 46% (quartiles: 0%, 81%; P = 0.011), while neutrophil filterability decreased by 28% (quartiles: 15%, 47%; P = 0.010). No significant changes in neutrophil parameters were found in the arterial blood. The study indicates that chemoattractants are released in the early reperfusion period of evolving myocardial infarction. These chemoattractants may act as inflammatory mediators causing neutrophil activation.

Aged↗
PubMed1992

[Anatomy of the flexor and extensor tendons].

The flexor and extensor tendons of the hand are equipped with special gliding mechanisms. Blood supply is provided via paratenon and in the fibro-osseous tunnel via mesotenon. The tendons show different amplitudes of active excursion which decrease distally. The function of flexors and extensors is coordinated and supplemented by reflexes and by the correlating relay system of lumbricals. Activation of extensor aponeurosis results via the so-called extrinsic and intrinsic system, where the IP joints are additionally linked functionally by the oblique retinacular ligaments of Landsmeer. At the level of the MP joint, the dorsal aponeuroses are furthermore linked by oblique fibrous structures, which lead to functional impairment of the neighboring MP joints in maximal flexion and extension of a finger due to an effect of tenodesis (so-called quadriga phenomenon).

Fasciotomy↗
PubMed1992

[Infection with Leptospira interrogans, serovar mozdok, in cattle].

In East Germany the same serovar, Leptospira mozdok, of the Pomona serogroup is found in cattle as well as in swine populations (Zieris 1989). Nowadays cases of bovine leptospirosis caused by infection with L. pomona have no significance. There are marked epizoological differences between infection with L. mozdok and L. pomona. The main source of infection with L. mozdok for cattle is the black striped field mouse (Apodemus agrarius). Secondary homonomous transmission occurs among the cattle. The clinical course of both infections is the same--including peracute, acute and chronic forms. Important prophylactic measures are effective rodent control and optimising hygiene conditions both in housing and on pasture. Veterinarians in abattoirs must consider leptospirosis in the differential diagnosis in cases with icteric signs, especially when the meat is derived from emergency slaughter.

Abortion, Veterinary↗
PubMed1989

[The importance of subclavian vein stenosis for the treatment of Dupuytren's contracture].

The postoperative healing in cases of Dupuytren's contracture is not only influenced by the age of the patient and the progress of the disease, but also by the existence of other accompanying diseases and general and local factors. The appearance of postoperative edema and the so-called hand-finger-syndrome are also especially unfavorable, because these complications determine the duration of treatment and the functional results. As a cause for these postoperative complications a disorder of the subclavian vein could be found and documented by means of phlebography. Preoperative examination of the venous situation is therefore an important diagnostic step to determine indications and to allow an estimation of the postoperative course and the duration of treatment. Demonstration of cases and statistical evaluation of our patients over the last five years show the importance of this observation.

Constriction, Pathologic↗
PubMed1988

[The quadriga phenomenon of the extensor tendon system and the superficial transverse metacarpal ligament].

The aponeurosis of the common extensor tendons is connected by intertendinous connections proximal to the metacarpophalangeal joints. These fibers are responsible for tenodesis effects in case of maximal finger extension and flexion and by this means they diminish the function of the other metacarpophalangeal joints. This mechanism can be described as the Quadriga-Syndrome of the extensor apparatus. These connecting structures also help to stabilize the transverse metacarpophalangeal arch and the position of the extensor tendons over the metacarpal heads. Cadaver dissections as well as operative findings have shown that there exists a superficial transverse intermetacarpal ligament, which connects the metacarpal heads in the area of its neck.

Finger Injuries↗
PubMed1987

[Unexplained pain conditions of the upper extremity].

Diagnosis can be very difficult in the case of painful conditions of the upper extremity, since this is a region where the site of the changes and pathologic conditions precipitating or causing the pain is not always identical with the area where the pain is felt. This is particularly so in the case of pain resulting from vascular disease and irritation of peripheral nerves and in the thoracic outlet and inlet syndrome. Recent observations and studies suggest that this is extremely important for the etiology and pathogenesis of epicondylar periostitis and tendovaginitis, carpal tunnel syndrome, and some trophic conditions affecting the hand. Stenosis of the subclavian vein can be responsible for post-traumatic and postoperative edema of the hand and for similar changes whose "cause is unclear", and also for certain difficulties with wound healing. Preliminary experience suggests that Sudeck's dystrophy may be the most severe form of the thoracic outlet and inlet syndrome. Accordingly, transaxillary decompression of the neurovascular cord with upper thoracic sympathectomy can be recommended as a last resort for refractory Sudeck's dystrophy. The problem of epicondylitis of the lateral humerus is discussed in some detail, as is the pathogenesis of pain resulting from neuroma.

Arm↗
PubMed1987

[Proximal ulnar nerve compression syndrome with special reference to the m. epitrochleo-anconaeus].

Subluxation and luxation of the ulnar nerve are normally congenital and can result in not only an irritation of the nerve but also sensory loss and motor weakness. The structures overlying the ulnar groove are responsible for the extent of nerve dislocation. In the case of subluxation, the ulnar nerve is compressed near the medial epicondyle by the edge of the ligamentous or muscular roof of the ulnar groove. In the case of luxation, ulnar nerve compression is located more distally under the aponeurotic arch of the M. flexor carpi ulnaris. We, therefore, distinguish between a proximal and a distal mechanism of nerve compression. In the years from 1970 to 1984 216 ulnar nerve compression syndromes in the elbow area have been treated and 208 cases have been evaluated. The authors found 77 proximal mechanisms (37%) and 54 distal mechanisms (26%). In 43 cases the proximal pressure was due to the ligamentum epitrochleo-anconaeum (20.7%) and in 34 cases to the epitrochleo-anconeal muscle.

Elbow Joint↗
PubMed1985

Sex-dependent endorphinergic and adrenergic control mechanisms of luteinizing hormone secretion in immature rats.

Previous studies in male and female immature rats have revealed striking sex differences as concerns endorphinergic and adrenergic control of luteinizing hormone (LH) secretion. The present study examines in 10 days old male and females rats whether these differences result from sexual differentiation of the brain, or acute effects of male and female gonadal hormones. The techniques employed to manipulate these mechanisms were gonadectomy immediately post-partum and androgenization. Androgenization on the 1st and 2nd day of life reduces the ability of naloxone to elevate serum LH levels in females, but failed to modify the LH-elevating effect of clonidine in males. Experiments with castrates showed that testosterone is critical for these sex-related differences. Treatment with testosterone on the 9th day of life of intact or gonadectomized rats revealed the ability of this hormone to modify LH-release acutely. We conclude that sexual differentiation of the brain may be of minor significance for the sex-related LH-control mechanisms in prepubertal rats. Of importance is the acute presence of testosterone, since in its absence male characteristics disappear.

Animals↗
PubMed1985

[Thoracic outlet syndrome and its significance for surgery of the hand (on the etiology and pathogenesis of epicondylitis, tendovaginitis, median nerve compression and trophic disorders of the hand)].

At present, the term "thoracic outlet syndrome" (TOS) is used as a term to include all factors compressing the nerves and vessels situated in the outlet of the thorax and the costo-clavicular area. It is marked by neurological and vascular disorders; their manifestation can be either spontaneous or posttraumatic. In case of surgical treatment the transaxillary approach (according to Roos) proved to be the best, and is indicated in therapy-resistant TOS, in certain cases of arterial complications and in outlet obstructions of the subclavian vein. Complete resection of the first rib and the most careful removal of all fibro-muscular structures affecting the artery, vein and brachial plexus are of importance to the result of the operation. In the evaluation of cases we found surprising success with cases of lateral epicondylitis. Thus, the nerve irritation asserted as a cause in 1962 is once more confirmed. The postoperative development of 38 median nerve compressions proved to be particularly astonishing. Twenty-five of those vanished without any need for additional measures, and in eight cases definite improvement was achieved. Another important fact was observed when five median nerve compressions, previously operated upon, disappeared only after a secondary TOS-operation. These observations led to a new pathogenetic concept of median nerve compression. Apart from the common causes, the primary predisposing factor for median nerve compression is a chronic oedema due to a functional blockage of the subclavian vein, clinically and radiologically substantiated. This oedema eventually leads to a carpal tunnel syndrome, either directly on account of swelling of fibrous structures or via metabolic disorders and oxygen deficiency, thereby causing an infiltrative and proliferative reaction. In this connection, it seems interesting that the results of recent pathohistological researches suggest that the chronic oedema is the greater pathogenetic factor. The improvement of painful tendovaginitis and different disturbances in wound healing after surgical treatment of the TOS shows the importance of subclavian vein compressions. Phlebographic examination of patients who suffer from Sudeck's atrophy demonstrates significant narrowing of the subclavian vein. The increasing pressure in the subfascial space and the irritation of the lower cervical plexus and the subclavian artery can promote Sudeck's atrophy.

Adolescent↗
PubMed1985

[Proximal radial nerve compression syndrome. Treatment and results].

Radial palsy after a single brisk contraction of the triceps muscle was first described by Gowers in 1892. The cause of such paralyses, which also can be found after chronic overexposure, in the course of fracture healing and because of inflammation or tumors, has not been explained until 1969. Two mechanisms are of importance for pressure effects on the radial nerve; either the nerve can be compressed in the hiatus nervi radialis due to swellings or a direct lesion occurs. The latter can happen because of a sudden brisk muscle contraction or on account of chronic trauma caused by the lateral head of the triceps. Since 1969, twenty patients with such radial nerve compressions have received surgical treatment and follow-up in our clinic.

Adolescent↗
PubMed1984

Sialyltransferase activity in tumor tissues.

Sialyltransferase (ST) activity was examined in tumor and control tissues. Within each group of control tissues a wide variation in the levels of ST activity was observed. Only in 20% of the tumors was the ST activity above the range of enzyme activity of the corresponding group of control tissues. Compared with its corresponding normal counterpart from the same individual, ST was elevated in tumor tissue by a factor of 2.1 on average. The distribution function indicates an increase in enzyme activity in 74% of the tumors. Other tumor markers were also determined for comparison. The ratio of the lactate dehydrogenase (LDH) subunits (M/H) was increased in tumors by a factor of 1.3 on average; the frequency of increase was 75%. From the distribution function of our data it follows that a decrease in the ratio of the creatine kinase (CK) subunits (B/M) occurs in 56% of tumors, the average factor being 0.8. The Regan isoenzyme of the alkaline phosphatase (AP) could be demonstrated in 13% of the tumors. In serum and in tissues ST was found to be composed of multiple forms. However, an isoenzyme of higher tumor specificity has not yet been established.

Alkaline Phosphatase↗
PubMed1984

Intracerebral injection of different antibodies against endogenous opioids suggests alpha-neoendorphin participation in control of feeding behaviour.

The mechanism of feeding behaviour of rats was examined. We used antibodies to different opioid peptides in order to reduce the tonic activity of various endogenous opioid peptide systems that may underly appetite. Unilateral microinjection of anti-alpha-neoendorphin antibodies into various areas of the ventromedial hypothalamus (VMH) inhibited food and water intake up to 45% in deprived animals. Injections outside this area failed to affect feeding. Administration of anti-beta-endorphin antibodies into the VMH moderately attenuated appetite. A considerable decrease of food and water intake was observed only upon injection of this antibody into the nucleus periventricularis hypothalami, a region generally believed to be involved with feeding. A marginal reduction of appetite was observed with anti-dynorphin antibodies injected into the VMH. These data may suggest that alpha-neoendorphin is involved in the control of food and water intake in the VMH.

Animals↗