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J Janssen

Publications and source records attributed to J Janssen.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Chemoimmunotherapy in the systemic treatment of advanced renal carcinoma].

Polychemotherapy and immunomodulating treatment using IL-2 and/or IFN-alpha produce objective responses in a proportion of advanced renal cell carcinoma patients. The goals of an improved cost effectiveness and therapeutic index of interleukin-2 and/or Interferon-alpha in combination with chemotherapeutic agents require the design of risk factor adapted individual therapeutic strategies for the outpatient setting. High dose i. v. IL-2 therapy in metastatic renal cell carcinoma has been proven effective [11]. Other modalities of applying IL-2 have been described [12-14] (Table 1). A cumulative risk-score identified three risk-groups with significant differences in median survival [16]. The SC use of IL-2 and INF-alpha has been established in the treatment of RCC [16, 23]. It appears that combination chemoimmunotherapy including p. o. retinoic acid is far more effective than single agent treatment. Further studies will have to be designed to improve therapeutic index and cost effectiveness in systemic combination therapy in metastatic RCC.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

The thermodilator: an effective instrument in the palliative therapy concept of malignant bile duct stenosis.

BACKGROUND AND METHODS: In the case of incurable malignant bile duct stenosis the aim of therapy is to secure the bile flow. Sometimes dilation of the stenosis is necessary to enable the introduction of a biliary duodenal stent or the replacement of a small-bore stent by a large-bore one. The previously most commonly used methods - bougienage and balloon dilation - can be unsuccessful with severe stenoses, which means that an extension of the endoscopic therapeutic instrumentarium is desirable. We examined the success rates and complications of a thermodilator which can be used to dilate bile duct stenoses. RESULTS AND CONCLUSIONS: In 21 out of 24 applications the therapeutic objective was achieved. In one case we observed an endoscopically controllable bile duct hemorrhage. The thermodilator is therefore a valuable addition to the endoscopic treatment possibilities of malignant bile duct stenosis.

Aged↗
PubMed1998

[Clinical value of endoscopic ultrasound-guided transesophageal fine needle puncture of mediastinal lesions].

BACKGROUND AND OBJECTIVE: As the mediastinum has been a region difficult to access for biopsy, mediastinoscopy has been required in most cases. In a prospective study the value of transoesophageal endoscopic ultrasound (TEUS) guided aspiration biopsy was assessed as an alternative. PATIENTS AND METHODS: TEUS-guided fine-needle aspirations were performed between May 1995 and March 1998 in 35 patients with mediastinal space-occupying lesions. In all cases the conventional endoscopic method or percutaneous puncture-sonography had been impossible or had failed. In one patient it had been performed after a negative mediastinoscopy. RESULTS: In 34 patients (97%) the aspirated tissue cylinder could be evaluated histologically. There were no complications. Malignancy was demonstrated in 24 patients, and there were one case each of sarcoidosis, silicoanthracosis and two cases of retrosternal goitre. In four of seven patients the negative preoperative diagnosis was confirmed at operation or by follow-up. There were two false-negative results and in one patient there has been no definitive diagnosis. The accuracy of the method was thus 91.4%, the positive predictive value for malignancy 88.9% and the negative predictive value for malignancy 72.7%. Ultrasound alone was a poor predictor of malignancy in lymph node enlargement. CONCLUSION: TEUS-guided fine-needle aspiration of space-occupying mediastinal lesions is an effective and low-risk method that can in selected cases shorten the diagnostic process and avoid methods that are expensive or lead to complications such as transpulmonary biopsy guided by computed tomography or mediastinoscopy.

Adult↗
PubMed1998

Biochemical and morphometric analyses show that myelination in the insulin-like growth factor 1 null brain is proportionate to its neuronal composition.

To elucidate the role of insulin-like growth factor 1 (IGF1) in the normal development of brain myelination, we used behavioral, biochemical, and histological analyses to compare the myelination of brains from Igf1(-/-) and wild-type (WT) littermate mice. The studies were conducted at postnatal day 40, at which time the Igf1(-/-) mice weighed approximately 66% less than wild-type mice. However, the Igf1(-/-) brain weight was only reduced by approximately 34%. Formal neurological testing showed no sign of central or peripheral myelinopathy in Igf1(-/-) mice. Myelin composition was not significantly different, and myelin concentration, normalized to brain weight or protein, was equal in Igf1(-/-) and WT mice. Likewise, concentrations of myelin-specific proteins (MBP, myelin proteolipid protein, MAG, and 2',3'-cyclic nucleotide,3'-phosphodiesterase) were not significantly different in Igf1(-/-) and WT mice. The myelin-associated lipids galactocerebroside and sulfatide were modestly reduced in Igf1(-/-) brains. Regional oligodendrocyte populations and myelin staining patterns were comparable in Igf1(-/-) and WT brains, with the notable exception of the olfactory system. The Igf1(-/-) olfactory bulb was profoundly reduced in size and was depleted of mitral neurons and oligodendrocytes, and its efferent tracts were depleted of myelin. In summary, this study shows that myelination of the Igf1(-/-) brain is proportionate to its neuronal composition. Where projection neurons are preserved despite the deletion of IGF1, as in the cerebellar system, oligodendrocytes and myelination are indistinguishable from wild type. Where projection neurons are depleted, as in the olfactory bulb, oligodendrocytes are also depleted, and myelination is reduced in proportion to the reduced projection neuron mass. These data make a strong case for the primacy of axonal factors, not including IGF1, in determining oligodendrocyte survival and myelination.

Animals↗
PubMed1998

Effect of diet and fluvastatin treatment on the serum lipid profile of kidney transplant, diabetic recipients: a 1-year follow up.

The effect of a cholesterol-lowering diet and subsequent fluvastatin treatment (Lescol, Novartis; 20 mg/day) on serum lipids and lipoproteins was investigated in 21 diabetic patients (eight women, 13 men, age range 31-63 years, BMI 25.9 +/- 4.5 kg/m2) who had undergone successful kidney transplantation. A cholesterol-lowering diet followed for 8 weeks had apparently no effect on serum lipid concentrations. Fluvastatin applied afterwards for 12 months significantly decreased the total cholesterol, triglyceride and LDL cholesterol levels from 7.7 +/- 0.94, 2.84 +/- 0.85 and 4.87 +/- 1.05 mmol/l to 6.40 +/- 0.74, 2.64 +/- 0.86 and 3.52 +/- 0.69 mmol/l, P < 0.001, < 0.05 and < 0.001, respectively, while the level of HDL cholesterol increased from 1.12 +/- 0.28 to 1.52 +/- 0.39 mmol/l, P < 0.001. Serum concentration of lipoprotein(a) remained unchanged. The serum level of apolipoprotein-A1 increased from 1.52 +/- 0.28 to 1.83 +/- 0.29 mmol/l (P < 0.01) and that of lipoprotein-B decreased from 1.37 +/- 0.20 to 1.20 +/- 0.36 mmol/l (P < 0.05). These maximum changes were achieved by the 12th week of fluvastatin treatment, and no further significant change was observed in the remaining part of the year. The other parameters that could have influenced lipid metabolism (doses of diuretics and steroid, daily dose and serum level of cyclosporin, kidney function, degree of proteinuria, HbA1c, etc.) remained unchanged throughout the study. Thus, the improvement in lipid concentrations can be ascribed exclusively to fluvastatin. No side effects were observed during the 1-year follow up. Liver enzymes and CPK remained within the normal reference limits. Fluvastatin proved to be an effective and safe drug for treating the dyslipidaemia of transplanted patients receiving steroid cyclosporin immunosuppression.

Adult↗
PubMed1997

[Transcutaneous sonography of the gastroesophageal junction in prospective comparison with endoscopy].

BACKGROUND AND OBJECTIVE: Despite its practical value, few data exist on assessing the gastrooesophageal junction by transcutaneous sonography (TS). A prospective study was undertaken to compare TS and endoscopy (ES) of this region. PATIENTS AND METHODS: Between 1 September, 1994 and 31 May, 1995 TS of the lower oesophagus was followed by ES of this region in 211 patients (116 women, 95 men; mean age 58.9 [14-90] years). None had previously been examined by ES or radiological contrast study of the oesophagus and stomach. Endoscopist and sonographer were blinded to each other's findings. The ability to visualize the abdominal oesophagus by TS and to recognize abnormalities were compared with ES results, both quantitatively and descriptively. RESULTS: The diaphragmatic course of the terminal oesophagus or (where present) a gastric hernia were well visualized by TS in all 211 patients. In 78 patients with normal results on TS and ES the visible length of the oesophagus was 3.3 +/- 0.8 cm, with a wall thickness of 4.5 +/- 1.0 mm (mean +/- standard deviation). In seven of eight patients with echo-poor wall thickness between 9 and 27 mm, suspected of being malignant, ES revealed neoplasm of the terminal oesophagus or cardia (six T2 to T4 carcinomas; one MALT lymphoma). One patient had involvement of the oesophagus and cardia as part of Crohn's disease. No case of malignancy remained unrecognized by ES. 64 of 77 hiatal hernias diagnosed by ES were also recognized by TS. Hiatal hernia was falsely diagnosed by TS in four patients. Oesophageal varices were correctly identified by TS in three of eight patients, as was one case of achalasia. CONCLUSION: Transcutaneous sonography is a good screening method with a high sensitivity for changes in wall architecture and it provides indications for further selective diagnostic procedures.

Adolescent↗
PubMed1997

Safety and efficacy of repeated shockwave lithotripsy of gallstones with and without adjuvant bile acid therapy.

BACKGROUND & AIMS: The value of adjuvant bile acid dissolution therapy after extracorporeal shockwave lithotripsy (ESWL) of gallbladder stones is under debate. A double-blind, randomized, multicenter trial was conducted to determine the safety and efficacy of repeated ESWL with and without adjuvant bile acid therapy. METHODS: At five centers, 153 patients with gallstones and good gallbladder emptying were randomized to undergo up to six high-energy lithotripsy sessions combined with ursodeoxycholic acid (UDCA, 750 mg/day; n = 77) or placebo (n = 76). RESULTS: Six months after the initial treatment, 77% of patients with small single stones (< or = 20 mm in diameter), 60% with large single stones (> 20 mm in diameter), and 41% with multiple stones were free of stones. Administration of UDCA had no effect on stone disappearance in the whole study group but tended to improve stone disappearance rates in patients with large single stones and tended to decrease biliary adverse effects in patients with multiple stones. CONCLUSIONS: Repeated high-energy ESWL without adjuvant bile acid therapy represents a safe and effective treatment in patients with small single stones and good gallbladder emptying. In patients with large single stones and multiple stones, adjuvant bile acid therapy may be beneficial.

Adjuvants, Pharmaceutic↗
PubMed1997

Argon plasma coagulation (APC) in gastroenterology: experimental and clinical experiences.

BACKGROUND: Diathermy procedures are indispensable in interventional endoscopy. Argon beam coagulation is an innovative no-touch electrocoagulation technique in which high-frequency alternating current is delivered to the tissue through ionized argon gas. METHOD AND PATIENTS: Before clinical application, we conducted in-vitro studies to investigate the depth and diameters of tissue coagulation in fresh operative specimens from the stomach, small intestine and colon. Five different power/gas flow settings between 40 and 155 W and 2 and 7 l/min were used. The impact time (1-10s) and the incident angle of the probe (45 degrees and 90 degrees) were also varied. The maximum depth of necrosis was 2.4 mm, the maximum diameter 1.1 cm. No perforation occurred even in critical areas such as the colon and duodenum. We therefore performed argon beam coagulation in 66 consecutive patients. Two power/gas flow settings of 40 and 70 W and 2 and 3 l/min, respectively, were used. The impact time and incident angle were varied individually. RESULTS: In 49 of the 50 patients with oozing haemorrhage from angiodysplastic lesions, polypectomy sites, erosions or ulcers or oozing of blood due to vascular penetration by tumours, definitive haemostasis was achieved in one to two sessions. In all 11 patients with residual sessile adenoma tissue, complete removal was possible. Oesophageal patency was restored in all five patients with stenosing tumours. In one patient with angiodysplasia of the caecal pole, an asymptomatic accumulation of gas in the submucosa was observed which resolved spontaneously. In two patients with extensive oesophageal carcinoma, there was a transitory--also asymptomatic--accumulation of gas in the mediastinum and peritoneal cavity but no evidence of perforation. CONCLUSION: Argon plasma electrocoagulation is an effective and relatively low-cost alternative to laser therapy in gastrointestinal endoscopy.

Adenoma↗
PubMed1997

[Non-operative management of pancreatitis with splenic involvement].

Pancreatitic pseudocysts of the spleen are rare events. We report two cases of conservative management of splenic involvement in pancreatitis by ultrasound-guided aspiration. The first patient was admitted with clinical and biochemical signs of acute exacerbation of chronic pancreatitis. The ultrasound examination showed a subcapsular anechoic zone in the spleen as well as pancreatic pseudocysts. The laboratory examination of the fluid obtained by ultrasound-guided aspiration confirmed the presence of an intrasplenic pancreatitic pseudocyst which disappeared completely after a second percutaneous aspiration. The second patient was admitted with acute exacerbation of chronic pancreatitis and septic symptoms caused by an abscess near the left lobe of the liver. After successful surgical drainage of the abscess the patient developed an expanding anechoic subcapsular fluid zone in the spleen. Quantitative decompression by ultrasound guided fine needle-aspiration confirmed the pancreatitic origin of the lesion which vanished within a few days without further treatment. We conclude that fine-needle aspiration of splenic pseudocysts under ultrasound control permits a differential diagnostic distinction from splenic abscess or hematoma and accelerates healing. There is thus a nonsurgical option for treatment of pancreatitic intrasplenic pseudocysts, provided that the patient is under close clinical observation.

Adult↗
PubMed1996

[Extracorporeal shockwave lithotripsy (SWL) of common bile duct calculi without previous endoscopic papillotomy].

In 17 patients (8 men, 9 women; mean age 61.5 years) with problematic bile-duct stones (papilla endoscopically inaccessible, residual bile-duct stones after recent laparoscopic cholecystectomy or age below 25 years) the chances of successful treatment by ESWL without sphincterotomy were examined. In 15 patients with solitary stones measuring up to 14 mm "pulverization-ESWL" produced complete freedom from stones after spontaneous migration of fragments through the intact papilla. Only two patients with two ductal stones measuring up to 15 mm still had residual fragments in the bile duct after treatment. The ideal stone for ESWL without sphincterotomy is thus the solitary bile-duct stone measuring up to 14 mm. Before performing a high-risk sphincterotomy, before re-operation and in young patients one should therefore always examine whether ESWL without sphincterotomy is indicated.

Adolescent↗
PubMed1995

Risks related to the introduction of exotic diseases: a European view.

The European Union (EU) has historically been free of a number of epidemic diseases of livestock and is approaching eradication of several others. This situation is put at risk by the importation of live animals and animal products. Animal products include products which are broadly described as veterinary biologicals. For the purposes of assessing and controlling risks, these fall into two groups: crude products (e.g. serum and other blood products) and medicinal products (e.g. vaccines and other immunological products). This second group is covered by another paper in this issue of the Review. Risk reduction methods may be applied to crude veterinary biologicals pre- or post-importation. Pre-importation methods include product treatment, or ensuring that the source of the product is "risk-free'. Post-importation risk reduction involves product testing, or treatment achieved by channelling products to commercial operations which are covered by European medicines legislation. At present, EU Member States issue health certificates individually for crude veterinary biologicals, and conditions for entry may differ between States. This process will soon be harmonised (the provisions for marketing medicinal products have already been harmonised).

Animal Diseases↗
PubMed1994

CAAS. II: A second generation system for off-line and on-line quantitative coronary angiography.

The Cardiovascular Angiography Analysis System (CAAS) has been completely redesigned and transferred to a modern platform. The user-friendly environment together with a number of image processing techniques and tools allow easy and fast analysis of cardiovascular angiographic images. These images are obtained either on-line by means of a frame grabber hooked on the video output of the X-ray equipment or off-line by digitising 35-mm cine film frames. In addition, images can be acquired more directly by means of a network link. Images stored on disk in different formats, including MS-DOS, can also be analysed. Accurate and reliable quantitative analysis of coronary stenoses and assessment of their related functional significance may offer the clinician a tool in a stratification of patients at risk. The semireal-time environment will make it possible for the cardiologist to quickly respond to the results of recanalisation procedures while the patient is still in the catheterisation laboratory. The addition of a video front end makes the system available to all clinically relevant X-ray imaging equipment. A detailed comparison with the former CAAS on the basis of analysis of 40 arterial segments in routinely acquired cineangiograms demonstrated no statistically significant differences between the two analysis systems. Repeated analysis of the same segments yielded inter- and intraobserver variabilities for the obstruction diameter of 0.096 and 0.108 mm, respectively. For the computed reference diameter the values are 0.099 and 0.096 mm, respectively, and for the percentage diameter stenosis 4.67 and 5.37%, respectively.

Computer Systems↗
PubMed1994

Form and function relationships in lateral line systems: comparative data from six species of Antarctic notothenioid fish.

The structure and physiology of the anterior lateral line canal systems were studied in six species of fish belonging to two different families within the suborder of antarctic fish Notothenioidei. Many of the canals within the species belonging to the genus Trematomus are relatively straight sided tubes with diameters around 0.4 mm. Some of the canals in Trematomus, and most of the canals in the icefishes (family Channichthyidae) are more complex. Relatively small pores lead into large tubules, the walls of which appear partially membranous, and the canals not much more than constrictions between adjacent tubules. Dissostichus mawsoni, a large species, has canals with distinctive wide and narrow sections, 1.8 mm and 0.48 mm, respectively. Despite these morphological differences the frequency response characteristics of anterior lateral line units are remarkably similar in all six species. In the case of D. mawsoni, this functional similarity results from narrow sections of the canals, which provide the viscous resistance to flow that preserves the mechanical filtering properties of the canal despite the huge size difference between D. mawsoni and the other species. It is argued that the most appropriate way to view canals is as high pass filters which attenuate lower frequencies, and that this effect is best illustrated by comparing the frequency response characteristics of superficial and canal neuromasts using a sinusoidal stimulus that has a constant peak-to-peak velocity. The functional contribution of canals is to attenuate low frequencies and improve the signal-to-noise ratio for biologically important signals in the presence of low frequency noise produced, for example, by the animal's own movements.

Animals↗