Search PubMed⌕ Search

Biomedical subjects

H Stobbe

Publications and source records attributed to H Stobbe.

At least 19 recordsLinked to original sources

Portal vein thrombosis: etiology, diagnostic strategy, therapy and management.

Myeloproliferative disorder, liver cirrhosis with portal hypertension, deficiency of natural anticoagulant proteins, gene mutation and hepatocellular carcinoma are the most frequent causes of portal vein thrombosis (PVT). Higher accuracy of the diagnostic methods is the reason why today the cause of PVT can be found more frequently. With imaging methods, PVT with or without cavernous transformation can be diagnosed. Fresh thrombus can be undetected in sonography due to the low echogenity but can be recognized in color Doppler sonography, especially with contrast-enhancing agent. Contrast-enhanced 3D MR angiography allows a comparable accuracy in the detection of PVT as digital subtraction angiography. Therapeutical options of PVT consist of mechanical recanalization of the portal vein, local fibrinolysis with or without placement of transjugular intrahepatic portosystemic stent shunt (TIPS), combination of mechanical recanalization and local fibrinolysis, systemic thrombolytic therapy, anticoagulation alone and surgical thrombectomy. Once PVT is found in sonography, Doppler sonography may be performed in order to distinguish benign from malignant thrombus. If further information is needed, MR angiography or contrast enhanced CT is the next step. If these tests are unsatisfactory, digital subtraction angiography should be performed. Until the early nineties, shunt surgery was recommended in patients with PVT who bled despite endoscopic treatment. Today, in symptomatic noncavernomatous PVT, recanalization with local methods is recommended. Additional implantation of TIPS should be performed when the patient is cirrhotic. In recent PVT in non-cirrhotic patients anticoagulation alone is recommended. It is expected that in old PVT anticoagulation can prevent further extension of the thrombus.

Animals↗

Imaging and radiological interventions of portal vein thrombosis.

Portal vein thrombosis (PVT) is diagnosed by imaging methods. Once diagnosed by means of ultrasound, Doppler ultrasound can be performed to distinguish between a benign and malignant thrombus. If further information is required, magnetic resonance angiography or contrast-enhanced computed tomography is the next step, and if these tests are unsatisfactory, digital subtraction angiography should be performed. Many papers have been published dealing with alternative methods of treating PVT, but the material is fairly heterogeneous. In symptomatic non-cavernomatous PVT, recanalization using local methods is recommended by many authors. Implantation of transjugular intrahepatic portosystemic shunt is helpful in cirrhotic patients with non-cavernomatous PVT in reducing portal pressure and in diminishing the risk of re-thrombosis. In noncirrhotic patients with recent PVT, some authors recommend anticoagulation alone. In chronic thrombotic occlusion of the portal vein, local measures may be implemented if refractory symptoms of portal hypertension are evident.

Angiography↗

A new heterozygous mutation of the FOXL2 gene is associated with a large ovarian cyst and ovarian dysfunction in an adolescent girl with blepharophimosis/ptosis/epicanthus inversus syndrome.

Blepharophimosis/ptosis/epicanthus inversus syndrome (BPES), an autosomal dominant syndrome in which eyelid malformation is associated with (type I BPES) or without premature ovarian failure (type II BPES). Mutations of a putative winged helix/forkhead transcription factor FOXL2 account for both types of BPES. We report on a 16-year-old adolescent girl with blepharophimosis and ptosis. Subsequently she developed oligomenorrhea, secondary amenorrhea for 6 months, and an extremely large cyst of one ovary. The cyst contained 8 l of cyst fluid and histopathology displayed a large corpus luteum cyst. Following laparotomy, gonadotropin levels were elevated (LH 17.2 U/l, FSH 29.4 U/l) and estradiol levels decreased (67 pmol/l). Because of clinical aspects of BPES and abnormal ovarian function we suspected a mutation of her FOXL2 gene and found a new in-frame mutation (904_939dup36) on one allele, leading to a 12 alanine expansion within the polyalanine domain. We conclude that the FOXL2 mutation 904_939dup36 may account not only for blepharophimosis and ptosis but also for ovarian dysfunction and growth of the large corpus luteum cyst. In contrast to known FOXL2 mutations with polyalanine expansions and association with BPES type II, clinical aspects of our girl may indicate some degree of ovarian dysfunction that might finally lead to BPES type I with premature ovarian failure.

Adolescent↗

Developmental stages and fine structure of surface callus formed after debarking of living lime trees (Tilia sp.).

Wounding of trees by debarking during the vegetative period sometimes results in the formation of callus tissue which develops over the entire wound surface or on parts of it. This light and transmission electron microscopy study of living lime trees found that the formation of such a surface callus is subdivided into three stages. During the first stage, numerous cell divisions take place in regions where differentiating xylem remains at the wound surface after debarking. This young callus tissue consists of isodiametric parenchymatous cells. Cambium cells, sometimes also remaining at the wound surface, collapse and do not contribute to callus formation. During the second stage, cells in the callus undergo differentiation by forming a wound periderm with phellem, phellogen and phelloderm. In the third stage, a cambial zone develops between the wound periderm and the xylem tissue laid down prior to wounding. This process is initiated by anticlinal and periclinal divisions of a few callus cells only. Later this process extends tangentially to form a continuous belt of wound cambium. Subsequently, this cambium produces both wound xylem and wound phloem and thus contributes to further thickening.

Cell Wall↗

Familial combined pituitary hormone deficiency caused by PROP-1 gene mutation. Growth patterns and MRI studies in untreated subjects.

BACKGROUND: Mutations of the prophet of PIT-1 (PROP-1), a paired-like homeodomain transcription factor which is responsible for early embryonic pituitary development, have recently been reported as a cause of combined pituitary hormone deficiency. METHODS: We describe the phenotype, long-term auxological data and MRI findings in two families with 4 affected members, all of whom have a mutation of the PROP-1 gene. GH, TSH, PRL, LH and FSH were completely deficient in all patients. RESULTS: ACTH deficiency was not diagnosed until the 3rd or 4th decades of life. Pituitary MRI showed an empty sella in 2 subjects, but unspecific tissue accumulation resembling a pituitary mass lesion in another patient. The affected boy from family II who was continuously treated with all the necessary hormones reached the familial target height. However, the 3 subjects in family I were only treated sporadically (GH treatment lasting from 1 to 3 years). CONCLUSION: Despite this insufficient therapy, final height was in the lower normal range. Longitudinal growth continued up to the age of 40 years in these subjects.

Adolescent↗

[The use of cross-sectional imaging modalities in the diagnosis of heart valve diseases].

Exact visualization of valve morphology seems to be possible with the cross-sectional imaging modalities, magnetic resonance imaging (MRI) and the recently introduced technique of multi-detector computed tomography (MDCT). These techniques are used, if other non-invasive imaging modalities, like echocardiography, fail or provide only insufficient information. This commonly occurs in the assessment of right ventricular valves. Quantification of valve stenosis is possible by calculating valve orifice area, which can be performed with MRI and MDCT. An estimation of the instantaneous peak gradient can only be achieved by MR flow measurements. MR flow measurement is a reliable method to quantify the degree of mild to moderate stenoses. Quantification of valve regurgitation is possible by measurement of the regurgitation fraction with MR flow measurements as well as with MR volumetry/CT volumetry. But only the MR flow measurement is suitable for the quantification of valve regurgitation in patients with multiple valves involved or cardiac shunting. MRI and probably MDCT are the most reliable methods in the evaluation of ventricular volumes and therefore suitable for the follow-up in patients with valvular heart disease, because changes in volumes are important for therapeutic decisions in these patients. The crucial advantages of MRI compared to CT in the diagnostic of valvular heart diseases however are the absence of radiation exposure, the possibility of quantitative evaluation of valves function using flow measurements and the higher temporal resolution as compared to MDCT.

Adolescent↗

Transjugular intrahepatic portosystemic shunt. Experiences at a liver transplantation center.

OBJECTIVE: Transjugular intrahepatic portosystemic shunt (TIPS) placement is an established therapy for portal hypertension that leads to variceal bleeding or refractory ascites. We present experiences of the role of TIPS at a liver transplantation center. MATERIAL AND METHODS: One hundred and ten patients were referred to the Radiological Department for TIPS placement. One of the 110 patients had recurrent cirrhosis after liver transplantation with refractory ascites. Function of the TIPS was controlled with Doppler US at 1 day, 1 week, 4 weeks and 4 months after TIPS placement and subsequently every 3 months. Shunt insufficiency was supposed when the blood flow velocity within the stent tract was under 50 cm/s and was an indication for TIPS revision. RESULTS: TIPS was placed in 101 patients. After TIPS placement, 10 patients underwent liver transplantation. While waiting for the new liver, none of them developed variceal rebleeding, ascites or other complications of portal hypertension. Two of the 101 patients had episodes of rebleeding. The frequency of patients undergoing TIPS revision within the first year after TIPS placement was 67.5%, within the second year 38.0% and within the third year 24.4%. The revisions led to sufficient reduction of the portosystemic pressure gradient. CONCLUSION: In some liver transplant candidates, TIPS can be useful in minimizing the risk of complications of portal hypertension during the waiting time for a liver transplantation. TIPS can be monitored by Doppler US and revised if occlusion occurs.

Adult↗

[How can Romberg disease be evaluated by means of MRI?].

Romberg disease, also known as progressive facial hemiatrophy (PFH), is an uncommon disease with progressive facial asymmetry as the major symptom. It is a atrophic process of the subcutaneous fatty tissue whose etiology is unknown. Skin, muscles and bones can be secondarily afflicted. With MRI evaluation we were able to show in 14 patients with PFH thinner subcutaneous fat, as well as flattening of the dermis in 12 of the 14. We divided the patients into three stages by the means of the MRI findings and found tendency towards concurrence between the MRI stage and the clinical stage.

Adolescent↗

[Automated speech recognition for the generation of medical records in computed tomography].

PURPOSE: A study was performed to compare the performance of automatic speech recognition (ASR) with conventional transcription. MATERIALS AND METHODS: 100 CT reports were generated by using ASR and 100 CT reports were dictated and written by medical transcriptionists. The time for dictation and correction of errors by the radiologist was assessed and the type of mistakes was analysed. The text recognition rate was calculated in both groups and the average time between completion of the imaging study by the technologist and generation of the written report was assessed. A commercially available speech recognition technology (ASKA Software, IBM ViaVoice) running on a personal computer was used. RESULTS: The time for the dictation using digital voice recognition was 9.4 +/- 2.3 min compared to 4.5 +/- 3.6 min with an ordinary Dictaphone. The text recognition rate was 97% with digital voice recognition and 99% with medical transcriptionists. The average time from imaging completion to written report finalization was reduced from 47.3 hours with medical transcriptionists to 12.7 hours with ASR. The analysis of misspellings demonstrated (ASR vs. medical transcriptionists): 3 vs. 4 for syntax errors, 0 vs. 37 orthographic mistakes, 16 vs. 22 mistakes in substance and 47 vs. erroneously applied terms. CONCLUSIONS: The use of digital voice recognition as a replacement for medical transcription is recommendable when an immediate availability of written reports is necessary.

Algorithms↗

Overexpression of cyclin D1 in human pancreatic carcinoma is associated with poor prognosis.

We have investigated the expression of cyclin D1 in adenocarcinoma of the pancreas and the relevance of cyclin D1 expression to clinical outcome. In comparison to normal pancreas, Southern blot analyses revealed amplification of the cyclin D1 coding gene in 25% of the cases, whereas with reverse transcription-PCR, overexpression of mRNA was observed in 82% of the examined tissues. Immunohistochemically, we could demonstrate nuclear overexpression in tumor cells in 68.4%, and this protein accumulation correlated significantly with poor prognosis [median survival, 18.1 versus 10.5 months; P < 0.01 (chi2 test)].

Adult↗

[Clinical aspects of autoimmune hemolytic anemias].

In a retrospective examination are evaluated the clinical, haematologic and immunohematologic findings as well as the courses of the disease of 119 patients with autoimmunohemolytic anaemia (AIHA), i.e. 113 AIHA by thermic autoantibodies (-wa) and 6 AIHA (-co), consequently, AIHA-wa were observed 19 times more frequently than AIHA-co. Symptomatic AIHA-wa appear somewhat more frequently than idiopathic forms (60:53). The serum iron values are in most cases within or near the normal region in idiopathic as well as in symptomatic AIHA-wa. In 75% of the patients with idiopathic AIHA-wa a remission of the haemolysis could be achieved by a glucocorticoid treatment. A primary immunosuppressive combination therapy (glucocorticoids + azathioprine) was successful in all 8 patients. In one third of the patients the AIHA-wa could be cured, on the one hand, after one year the lethality was 33% (Dacie 1963 still 46%). The indication for splenectomy is discussed, since by means of this third therapy possibility a favourable influence of the course could be achieved in half of the 22 patients with symptomatic and idiopathic AIHA-wa. The importance of the thromboembolic complications is to be confirmed. So pulmonary embolisms are the most frequent cause of death in the 53 patients with idiopathic AIHA-wa. The concentration of the patients with AIHA in haematologic centres proved to be advantageous for these patients.

Adult↗

[Rational hematologic diagnosis with reference to modern laboratory procedures].

The spectre of methods for the diagnostics and differentiation of haemolytic anaemias, particularly for the establishment of congenital, autoimmune haemolytic, drug-conditioned and other anaemias is treated. The clear delimitation of an iron deficiency from a disturbance of the iron distribution is advantageously to be achieved by iron staining of the bone marrow and by a determination of serum ferritin. The value of the diagnostic methods in megaloblastic anaemia is classified according to newer knowledge, in which case the vitamin-B12-absorption test and the serum level determination of vitamin B12 by no means range in the first place. Long-term culture results of haematopoietic stem cells are particularly evident in the aplastic syndrome of the bone marrow and further haematological diseases concerning the establishment of the intensiveness of proliferation. The classification of the acute leukemias demands conventional as well as cytochemical staining methods; recently, it is essentially improved using monoclonal antibodies. In leukemias cytogenetic investigations are more and more attracted to the estimation of the prognoses. In lymphogranulomatosis among others functional disturbances of the cellular immunity, in the group of the non-Hodgkin-lymphomas haematological, protein-analytic and immunological laboratory investigations are methods supporting the diagnosis. Altogether is to be established that the haematological diagnostics has become more and more perfect, in which case apart from new techniques old approved methods are still further used.

Anemia, Aplastic↗