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J de Vries

Publications and source records attributed to J de Vries.

At least 73 records · Page 4Linked to original sources
PubMed1999

Local resection of biliopancreatic cancer.

Biliopancreatic tumors that are potentially amenable to local resection include proximal bile duct tumors (Klatskin tumors), mid-choledochal duct tumors and tumors arising from the papilla of Vater. This paper reviews our experience in the AMC, with local resection of these conditions. From 1983-1997, 112 patients underwent surgical resection of a carcinoma of the hepatic duct confluence (Klatskin tumor). Local resection was undertaken in 80 patients (52 patients with type I and II tumors, and 28 patients with type III tumors) whereas in 32 patients with type III tumors, hilar resection was performed with liver resection. Negative surgical margins were achieved in 10 patients after local resection of type I and II tumors (19.2%), in 1 patient after local resection of a type III tumor (3.6%), and in 5 patients after hilar resection and liver resection (15.6%). Middle-third carcinomas of the extra-hepatic biliary tract are less common than proximal or distal bile duct tumors. From 1993-1998, 12 patients underwent resection of a mid-choledochal duct carcinoma. In 8 patients, local resection was performed and in 4 patients, subtotal pancreatoduodenectomy (PPPD) because of the close relationship of the tumor and the pancreas. Four patients had negative surgical margins, 2 after local resection (25%) and 2 after PPPD (50%). Although accepted for villous adenomas located in the ampulla, local resection for ampullary carcinoma is controversial. Nine patients underwent local resection of a presumed adenoma that proved to be an ampullary carcinoma. In 4 patients with T1 tumors, resection of the carcinoma was locally complete (44%). Additional PPPD was performed in 6 patients, including the 4 patients with complete local resections, showing no residual tumor at the previous site of excision, but, lymphnode metastases in two resection specimens (both of patients with presumed T1 tumors). Hence, local resection of a T1 ampullary carcinoma might result in tumor free margins, but does not deal with (usually retropancreatic) lymphnode metastases. In conclusion, local resection is applicable to Klatskin type I and II tumors. Local resection may be considered in the proximally located, mid-choledochal duct carcinomas but, when located closer to the pancreas, PPPD is the preferred treatment. For ampullary adenomas, local resection is feasible unless frozen section examination raises suspicion on a malignancy. Local resection of even limited ampullary carcinomas is not advisable because of lymphatic dissemination of the tumor and consequently, inadequate clearance.

Adolescent↗
PubMed1998

Detection of nptII (kanamycin resistance) genes in genomes of transgenic plants by marker-rescue transformation.

We have developed a novel system for the sensitive detection of nptII genes (kanamycin resistance determinants) including those present in transgenic plant genomes. The assay is based on the recombinational repair of an nptII gene with an internal 10-bp deletion located on a plasmid downstream of a bacterial promoter. Uptake of an nptII gene by transformation restores kanamycin resistance. In Escherichia coli, promoterless nptII genes provided by electroporation were rescued with high efficiency in a RecA-dependent recombinational process. For the rescue of nptII genes present in chromosomal plant DNA, the system was adapted to natural transformation, which favours the uptake of linear DNA. When competent Acinetobacter sp. BD413 (formerly A. calcoaceticus) cells containing the mutant nptII gene on a plasmid were transformed with DNA from various transgenic plants carrying nptII as a marker gene (Solanum tuberosum, Nicotiana tabacum, Beta vulgaris, Brassica napus, Lycopersicon esculentum), kanamycin-resistant transformants were obtained roughly in proportion to the concentration of nptII genes in the plant DNA. The rescue of nptII genes occurred in the presence of a more than 6 x 10(6)-fold excess of plant DNA. Only 18 ng of potato DNA (2.5 x 10(3) genome equivalents, each with one copy of nptII) was required to produce one kanamycin-resistant transformant. These experiments and others employing DNA isolated from soil samples demonstrate that the system allows reliable and highly sensitive monitoring of nptII genes in transgenic plant DNA and in DNA from environmental sources, such as soil, without the need for prior DNA amplification (e.g. by PCR).

Acinetobacter↗
PubMed1998

Clinical presentation of sarcoidosis in The Netherlands an epidemiological study.

BACKGROUND: Patients suffering from sarcoidosis may present with a wide range of symptoms. The aim of this study was to make an inventory of the clinical presentation of the sarcoidosis population in the Netherlands. METHODS: Symptom inventory questionnaires were sent to all members of the Dutch Sarcoidosis Society. Of these 1755 sarcoidosis patients, 1026 (58%), (age 46.7 +/- 11.6, female 63%) completed the questionnaire. RESULTS: Familial sarcoidosis was reported by 170 patients (16.3%). In 57% of the cases the first diagnosis was sarcoidosis. Other diagnosis included rheumatoid arthritis (5.1%) and tuberculosis (4.8%). Treatment with systemic corticosteroids was reported by 565 patients (55.1%). The most frequently reported symptom was fatigue (71%), followed by dyspnea (70%), arthralgia (52%), muscle pain (39), chest pain (27%), and general weakness (22%). Moreover, 26% of patients suffered from disease-related tension and strain. No relationship was found between the reported symptoms and treatment with corticosteroids. CONCLUSIONS: Sarcoidosis patients suffered from a broad range of persistent physical symptoms. In this study fatigue appeared to be the most commonly reported symptom. Intervention programs should focus on physical health as well as psychosocial aspects such as teaching patients how to cope with the disease.

Adult↗
PubMed1998

Improved staging of breast cancer through lymphatic mapping and sentinel node biopsy.

Sentinel node biopsy is a less invasive technique for staging breast cancer than complete axillary lymph-node dissection and may be as accurate. In the case of a 71-year-old woman with a T1 breast cancer, sentinel node biopsy improved staging. Metastases were discovered in sentinel nodes outside the axilla while the axillary nodes were tumour-free.

Aged↗
PubMed1998

Evaluation of quality of life in sarcoidosis patients.

Health-related quality of life (QOL) has become an important topic in health care. However, hardly any attention has been paid to QOL in sarcoidosis. Therefore, the aim of this study was to assess the impact of sarcoidosis on QOL. Sixty-four sarcoidosis patients completed the World Health Organization Quality of Life assessment instrument (WHOQOL-100) and the Beck Depression Inventory (BDI). For the WHOQOL-100 a matched group of healthy controls was selected. Patients were divided into two groups: group I (n = 37) consisted of patients with actual symptoms, group II (n = 27) consisted of asymptomatic patients. The WHOQOL-100 revealed a number of areas in which sarcoidosis patients, especially those with current symptoms, experienced problems. A major symptom in both groups of sarcoidosis patients was fatigue. No association between the facet fatigue and the domain psychological health was found. Depressive symptoms (BDI) were associated with psychological function (WHOQOL-100). No association between pulmonary function tests and QOL was found. In conclusion, this study shows that sarcoidosis has a considerable impact on the QOL of patients. The WHOQOL-100 appeared to be a sensitive instrument to measure fatigue--one of the most common symptoms in sarcoidosis--which otherwise is difficult to assess objectively.

Adult↗
PubMed1998

The micro-plethysmograph: a new device to measure small volume displacements by isolated human airway segments.

For the study of airway responsiveness in vitro, airway segments have important advances over strip or spiral preparations. The method to study isobaric contraction of segments is not well established. The aim of this work was to develop a model to assess the smooth muscle responses in isolated airway segments under isobaric conditions. We developed a microplethysmograph with a volume measurement range of 10 to 700 microL, a resolution of 0.02-0.4 microL, and a drift of 2.6-0.7% of measurement range min(-1) for its most and least sensitive setting, respectively. The plethysmograph is able to compensate for the pressure changes induced by the volume changes, enabling for true isobaric measurements. We show examples of the isobaric contraction and relaxation of isolated human airway segments after stimulation of an airway segment by methacholine, isoprenaline, or electrical field stimulation. Apart from studying airway responses, the micro-plethysmograph is potentially useful to study the contractile properties of watertight and hollow structures like blood vessels, gut, and ureter. In addition, this device can be used to measure leak or diffusion at any transmural pressure.

Air Pressure↗
PubMed1998

Optic neuropathy in McCune-Albright syndrome: an indication for aggressive treatment.

McCune-Albright syndrome consists of the triad polyostotic fibrous dysplasia, café-au-lait spots and autonomous hyperfunction of one or more endocrine systems. The most frequent neurological complication of craniofacial fibrous dysplasia is visual loss. We describe a 17-y-old boy with McCune-Albright syndrome and acute loss of vision in the left eye caused by encroachment of the left optic nerve by fibrous dysplastic lesions. Neurosurgical intervention improved left eye vision. Aggressive intervention is indicated in cases of acute visual loss in patients with craniofacial fibrous dysplasia. This is supported by a review of other reported cases.

Adolescent↗
PubMed1998

Topic selection in undergraduate medical education and relevance to general practice.

Most patients who have possibly malignant diseases are first seen by physicians not specifically trained in oncology. The cancer education that undergraduate medical students receive is frequently dominated by basic science topics, detailed staging data, pharmacology of cancer drugs, and treatment protocols. This is not in accordance with the needs in general practice. In pre-course information and correspondence with reference to the International Summer School "Oncology for Medical Students," held in Groningen, The Netherlands, it is emphasized that the Summer School focuses on cancer care in general practice. As part of the education program participants are required to prepare abstracts and posters on oncologic topics in general health care in their own countries. Despite the emphasis on cancer care in general practice and despite suggestions for topics, some students have first sent in abstracts describing basic sciences research projects. Evidently during their medical training the relevancy of cancer education to the reality of daily practice had not been taught or had already been lost. In teaching undergraduate medical students, it should be realized that the vast majority will choose non-oncology disciplines. Thus, cancer education of these students should focus mainly on clinical cancer issues that are relevant in general practice.

Abstracting and Indexing↗
PubMed1998

Use of fibrin glue to protect tissue during CO2 laser surgery.

OBJECTIVE: Accidental injury of tissues during CO2 laser irradiation can lead to serious morbidity, especially during ear, nose, and throat, neurosurgical, and plastic-reconstructive procedures. This experimental study describes a new technique in which vital structures are coated with a thin layer of fibrin glue to protect them from accidental CO2 laser irradiation. STUDY DESIGN/MATERIALS AND METHODS: The femoral neurovascular bundles (femoral artery, vein, and nerve) of 12 rats were exposed. On one side the bundle was coated with fibrin glue, which is a biological two-component glue consisting of fibrinogen solution and thrombin. Upon application, an elastic mass on the neurovascular bundle was formed. The contralateral neurovascular bundle was left uncoated. Subsequently both bundles were subjected to CO2 laser irradiation at different powers (5, 7, and 9 W), with an irradiation time of 0.1 seconds. Light microscopy was performed at 30 minutes and 2 days after surgery. RESULTS: No macroscopic visible hemorrhages occurred during laser irradiation in the glue-coated bundle. Light microscopic evaluation revealed an undamaged neurovascular bundle without any signs of thermal damage. In the uncoated bundles intraoperative hemorrhages resulting from laser energy occurred in all specimens. Furthermore, severe thermal damage was present in arteries, veins, and nerves. CONCLUSIONS: Intraoperative coating with fibrin glue can serve as a shield to protect vital structures such as arteries, veins, and nerves from accidental CO2 laser exposure.

Animals↗
PubMed1998

Protective coating of cranial nerves with fibrin glue (Tissucol) during cranial base surgery: technical note.

OBJECTIVE: Cranial nerve deficit, either transient or permanent, is a common postoperative complication after cranial base surgery. Frequently, this occurs because intracranial nerves are directly involved in the cranial base lesion. However, any cranial nerve adjacent to the lesion can be damaged because of direct or indirect manipulation during surgery, leading to severe morbidity. We describe a new technique in which the adjacent intracranial nerves are protected from surgical trauma by coating the nerves with a biological two-component fibrin glue (Tissucol; Immuno A.G., Vienna, Austria). SURGICAL TECHNIQUE: The technique was performed in patients who underwent cranial base surgery for different types of lesions. After exposure of the operating field, the cranial nerves that were at risk of operative trauma were coated with a thin layer of fibrin glue using a double lumen catheter within a traditional suction device. RESULTS: With the application of fibrin glue, a protective layer of a rubbery consistency is formed around the nerve. No intraoperative complications or adverse effects of the application were noted. Moreover, no surgical injury of the nerves occurred and no or minimal postoperative cranial nerve deficit was noted in the coated nerves. CONCLUSION: Although it is difficult to compare the postoperative cranial nerve deficit in the coated nerves with a control group, we think that this technique is a valuable method to minimize or avoid intraoperative cranial nerve injury during cranial base surgery.

Cranial Nerve Injuries↗
PubMed1998

Comparison of the lightweight Camp Normal Activity Foot with other prosthetic feet in trans-tibial amputees: a pilot study.

Clinically relevant information regarding the useability of prosthetic feet is scarce. The industry is not obliged to perform clinical studies before marketing the product. Clinicians however are limited in their possibilities (organisation and finance) to determine the useability of a technical product. This small study is an example of how in general the useability of a technical product is established in clinical practice. The Camp Normal Activity Foot (CNAF), a carbon prosthetic foot, was compared objectively and subjectively with a number of other prosthetic feet (same price bracket) in three subjects with trans-tibial (TT) amputations. The CNAF is low in weight and has favourable stiffness and hysteresis properties. The stiffness of the pylon of the CNAF seems to be limited as also is the possibility of adaptation of the CNAF. The CNAF distinguishes itself, in this study, but not convincingly with respect to the energy consumption in walking, the step-time parameters (symmetry) and the subjective judgement of the users. An additional virtue of the CNAF seems to be its light weight.

Adult↗
PubMed1998

Successful surgical repair of progressive exophthalmos caused by a meningocele in a patient with neurofibromatosis Type 1. Case report.

A case of surgical repair of progressive exophthalmos of the right eye in a 43-year-old woman with neurofibromatosis Type 1 (NF1) is presented. Preoperatively, the patient's ocular movements and visual fields were intact. Visual acuity was 20/30 on the right side and 20/20 on the left. Computerized tomography scanning demonstrated complete absence of the superolateral orbital wall on the right side with a large meningocele protruding into the right orbit. Intraoperatively, a new superolateral wall was constructed using the inner table of the left frontal bone as a bone transplant. A free galeoperiosteum flap was used for water-tight dural reconstruction. A few weeks postoperatively the patient's exophthalmos showed remarkable resolution. Her ocular movements, visual acuity, and visual fields remained unchanged. In conclusion, reconstruction of the superolateral wall and repair of a meningocele in a patient with NF1 is worthwhile and can be followed by excellent cosmetic results. More important, the patient's visual functions remain preserved.

Adult↗
PubMed1998

Quality of life and depressive symptoms in patients suffering from sarcoidosis.

BACKGROUND: Apart from the disease status, chronically ill patients are confronted with stressors like dependence, limitations in mobility and physical complaints. Data on patients with sarcoidosis, however, are lacking. The aim of this study was to investigate the quality of life (QOL) and the influence of QOL factors on depressive symptoms in these patients. PATIENTS AND METHODS: Sixty-four patients with histologically proven sarcoidosis participated in this study. Significant co-morbidity was excluded. The Sickness Impact Profile (SIP) was used to determine the QOL. Depressive symptoms were measured with the Beck Depression Inventory (BDI), of which a subset of items measured cognitive symptoms, the Cognitive Depression Index (CDI). Disease status was assessed by pulmonary function parameters (FEV1, Dco), complaints and illness duration. To control for a confounding cognitive style of self-report, the Positive Affect Negative Affect Schedule (PANAS) was administered. RESULTS: The major complaint was fatigue. QOL was related to the perception of complaints, but not to the assessed disease status. In a multivariate regression 86% of the variance could be explained in BDI-scores, and 83% in CDI-scores. After controlling for demographical factors, disease status and cognitive style, QOL contributed to the regression, explaining another 17% of variance of BDI-scores as well as CDI-scores. Problems with sleeping were associated positively with depressive symptoms in general (beta = 0.38) and depressive cognitions only (beta = 0.32). CONCLUSIONS: In sarcoidosis, QOL factors were associated with depressive symptoms. These results suggest that patients with sarcoidosis may profit from attention to the psychosocial as well as the somatic aspects of this disease.

Adult↗
PubMed1998

Sperm penetration assay in predicting successful in vitro fertilization. A meta-analysis.

OBJECTIVE: To determine if the performance of the sperm penetration assay (SPA) is useful in predicting successful in vitro fertilization (IVF). METHODS: A meta-analysis was set up to determine the performance of SPA in the prediction of IVF success. We collected data on 647 patients in 24 studies. For each study, a two-by-two table was constructed from the results of SPA and IVF. RESULTS: The sensitivity and specificity of SPA as compared to IVF were heterogeneous. A summary receiver operating characteristics curve could be estimated, showing that the sensitivity of SPA was only 37%, with a specificity of 95%. Subgroup analysis did not explain the lack of homogeneity. CONCLUSION: Since withholding IVF inappropriately has major consequences, performing SPA is insufficient for selecting patients for treatment with IVF-embryo transfer.

Animals↗