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J C Bos

Publications and source records attributed to J C Bos.

12 recordsLinked to original sources
PubMed2006

[Optimising antibiotic policies in the Netherlands. IX. SWAB guidelines for antimicrobial therapy in adults with acute infectious diarrhoea].

The 'Stichting Werkgroep Antibioticabeleid' (SWAB; Dutch Working Party on Antibiotic Policy) develops evidence-based guidelines for the use of antibiotics in hospitalised adults. This guideline on acute infectious diarrhoea (AID) concerns the antibiotic treatment of acute infectious inflammation of the gastrointestinal tract, manifesting primarily as diarrhoea. AID can be subdivided into community-acquired diarrhoea, traveller's diarrhoea and hospital-acquired (nosocomial) diarrhoea. In the first 2 categories, the need for antibiotic treatment is generally restricted to individuals with severe illness, dysentery or a predisposition to complications. High rates of primary fluoroquinolone resistance can be found in human Campylobacter isolates from the Netherlands and from other parts of the world. Therefore, if antibiotic treatment is necessary for community-acquired AID or AID in travellers returning to the Netherlands, it is advised to use oral azithromycin for 3 days as empirical treatment. If intravenous treatment is necessary, the combination of ciprofloxacin and erythromycin for 5-7 days may be considered. As soon as the identity of the causative organism is known, antimicrobial treatment should be tailored accordingly.

Acute Disease↗
PubMed2003

Emergency resection of an extra-adrenal phaeochromocytoma: wrong or right? A case report and a review of literature.

Phaeochromocytomas are rare neuroendocrine tumours that produce symptoms through excess release of catecholamines. Treatment of choice is elective, complete surgical removal after pretreatment with alpha-adrenergic blocking drugs, to prevent dangerous haemodynamic fluctuations. In rare cases a 'catecholamine crisis' develops presenting with pulmonary oedema and circulatory shock. We report such a case of a patient with familial extra-adrenal phaeochromocytoma who successfully underwent emergency surgery. Pathophysiological mechanisms are discussed. Although pretreatment with alpha-adrenergic blocking drugs seems advisable in terms of morbidity and mortality, the concept is based on theory rather than clinical evidence. Surgical management of a catecholamine crisis is associated with high mortality rates. However, proof of better outcome by avoidance or discontinuation of emergency surgery is not available. Based on literature and on this case, we conclude that emergency surgery in phaeochromocytoma does not have to be structurally avoided and may be considered under life-threatening circumstances.

Adrenal Gland Neoplasms↗
PubMed2000

Hemodialysis-induced degranulation of polymorphonuclear cells: no correlation between membrane markers and degranulation products.

BACKGROUND/AIMS: Degranulation of polymorphonuclear leukocytes (PMN) during hemodialysis (HD) is usually assessed by measuring degranulation products. However, this process might also be estimated by the assessment of cell surface markers. In this study, the relationship between the expression of PMN degranulation markers (CD63 and CD66b) and the release of degranulation products [myeloperoxidase (MPO) and lactoferrin (LF)] was investigated during clinical HD in order to evaluate cell surface markers as a useful index of PMN degranulation. METHODS: The expression of CD63 and CD66b on PMN and the release of MPO and LF were investigated in 10 chronic HD patients, during both heparin (HDhep) and trisodium citrate anticoagulation (HDcit), in a randomized order. Samples were drawn from both the efferent and afferent lines of the dialyzer at 0, 7.5, and 180 min. RESULTS: During HDhep at first passage, a major increase in MPO (from 158 +/- 32 to 448 +/- 177 microg/l, p = 0.001) and LF (from 134 +/- 52 to 260 +/- 120 microg/l, p = 0.01) was found across the dialyzer, whereas marked changes were not observed during HDcit. The expression of CD63 and CD66b increased across the dialyzer during both anticoagulation modalities, but was only significant in the case of HDhep (CD63: mean fluorescence intensity from 247 +/- 61 to 331 +/- 118, p < 0.01; CD66b: mean fluorescence intensity from 340 +/- 76 to 434 +/- 103, p = 0.01). During HDhep a correlation was noted between the degranulation products and markers of both azurophilic and specific granules (MPO and CD63: r = 0.35; p < 0.01; LF and CD66b: r = 0.39, p < 0.01). Significant differences in the expression of CD63 and CD66b between HDhep and HDcit were not observed. When analyzing the combined data for both HDhep and HDcit, no correlation was observed between degranulation products and markers. CONCLUSION: Our data suggest that the measurements of cell surface markers may not be a reliable indicator of the degree of HD-induced PMN degranulation.

Adult↗
PubMed1997

Mechanisms of intra-dialyser granulocyte activation: a sequential dialyser elution study.

INTRODUCTION: During haemodialysis (HD), an early and transient white blood cell (WBC) reduction is noted in the peripheral blood, which has been attributed mainly to the sequestration of polymorphonuclear cells (PMN) in the pulmonary vasculature. However, WBC also adhere to the dialyser, as demonstrated before in an elution study performed after HD. In the present study, we investigated if intradialyser WBC sequestration contributes to the WBC nadir in the blood shortly after the start of HD and whether or not different mechanisms underlie PMN adherence in dialyser and lung. In addition, PMN degranulation was analysed not only in peripheral blood but also in dialyser eluates (DE). SUBJECTS AND METHODS: Dialysers were eluted after 7 1/2 (DE-7 1/2) and 180 (DE-180) min of HD in eight patients. Blood samples were taken before HD (t0), and at t7 1/2 and t180. Besides WBC count and differentiation, PMN adhesion (CD11b and CD62L) and degranulation markers (CD63 and CD66b) were assessed by flow cytometry. RESULTS: In the blood, a WBC fall was noted at t7 1/2 (from 5.8 to 4.8 x 10(9)/l; absolute about 5 x 10(9) cells). DE contained 3.0 x 10(6) cells at t7 1/2, and 57.2 x 10(6) at t180 (P = 0.015). As for CD11b, at t7 1/2 both in the blood and DE an increased expression was observed, as compared to t0 (P = 0.01); CD11b expression in DE-7 1/2 was higher than in DE-180 (P = 0.025). In contrast, CD62L showed downregulation only in DE both at t7 1/2 (mean fluorescence intensity (MFI) PB 4172 and DE-7 1/2 2353, P = 0.01), and at t180 (MFI 794, P = 0.03 versus DE-7 1/2), when compared to blood at t0. As for degranulation markers, an increase was observed in blood at t7 1/2 (MFI CD63 from 357 to 506, P = 0.02; CD66b from 507 to 794, P = 0.001), in comparison with t0. Eluted PMN at t7 1/2 showed a higher expression of CD63 than PMN in blood at t7 1/2 and DE-180 (MFI in DE-7 1/2 1280 and blood 506, P = 0.003). The expression of CD66b was increased in DE-7 1/2 (MFI 1803 versus blood 794, P = 0.01), and even more in DE-180 (MFI 2763, P = 0.002), when compared to blood. CONCLUSIONS: From these data it is concluded first, that intradialyser PMN sequestration does not contribute markedly to the WBC nadir in the circulation. Second, intradialyser PMN trapping appears to result primarily from non-adhesion-molecule-mediated factors, as indicated by an increased expression of CD11b at t7 1/2 on eluted PMN associated with low cell numbers in DE, and normalized CD11b expression at t180 associated with considerably higher cell numbers in DE. Third, HD-induced degranulation seems to be a complex phenomenon. After a rapid transient onset, characterized by an early upregulation of CD63 and CD66b on PMN leaving the dialyser, degranulation continues within the device as indicated by an additional rise in the expression of CD66b on PMN in DE-180.

Adult↗
PubMed1997

Low polymorphonuclear cell degranulation during citrate anticoagulation: a comparison between citrate and heparin dialysis.

INTRODUCTION: Haemodialysis (HD)-induced bio-incompatibility includes alterations in both cellular elements and humoral factors. As far as polymorphonuclear (PMN) cells are concerned, an increase in both adhesion and degranulation has been reported. However, whereas increased PMN adherence and aggregation is highly linked with early transient complement activation, degranulation seems a continuous process, independent from the formation of complement degradation products. In the process of cell activation, including PMN degranulation, divalent cations (Ca2+) appear to play a pivotal role. As regionally administering citrate creates an almost Ca(2+)-free environment within the dialyser, it is tempting to speculate that Ca2+ dependent phenomena of bio-incompatibility, originating within the dialyser, can be attenuated by substituting conventional heparin for citrate. METHODS: Therefore, both anticoagulation modalities were compared in 10 stable patients, undergoing haemodialysis (HD) treatment with cellulose-triacetate membranes (CTA) only. Apart from the intracellular granule products myeloperoxidase (MPO) and lactoferrin (LF), the classical parameters of bio-incompatibility, peripheral blood neutropenia and complement activation, were measured. RESULTS: Analysis of MPO and LF gradients across the dialyser (concentration in efferent line-concentration in afferent line) suggested that degranulation is an early process, that occurs mainly within the extracorporeal circuit. Citrate abolished the release of MPO almost completely, whereas LF release was partially inhibited. Neither neutropenia, nor complement activation could be correlated with the occurrence of degranulation. CONCLUSIONS: HD-induced PMN degranulation seems largely independent from complement activation, but primarily reliant on Ca2+, at least in the case of CTA membranes.

Adult↗
PubMed1996

Ex vivo elution of hemodialyzers. An additional criterion for the assessment of bioincompatibility.

The analysis of hemodialysis (HD)-related bioincompatibility is focused mainly on phenomena observed in peripheral blood. However, since biocompatibility originates inside the dialyzer, white blood cells (WBC) adhering to the dialyzer are probably most subject to the influence of both dialyzer membrane and dialysate. In order to collect membrane-adherent cells, a reliable and reproducible elution technique was developed. After 3 h of HD, blood was returned to the patient with 0.9% NaCl. Then, dialyzers were eluted by recirculation of phosphate-buffered saline (PBS) or PBS/3 mM EDTA for 20 min, with or without prior flushing with 200 ml PBS. Finally, remaining adherent cells were collected by an afterwash with 10% trypsin. These solutions, as well as blood samples, were analyzed for WBC count, viability and differentiation. Random eluate samples were analyzed by flow cytometry, and the influence of elution on PMN activation was tested in a separate control experiment. WBC numbers decreased by flushing before elution, whereas cell numbers were maximal after elution with PBS/3 mM EDTA (30 x 10(6)). Trypsin afterwash resulted in a further yield of 12 x 10(6) cells. The eluates contained 81% PMN (blood 68%, p < 0.01), with a degranulated appearance, and only 12% lymphocytes (blood 21%, p < 0.05); cell viability in the eluates was > 95%. The eluted cells could be analyzed by flow cytometry, and the procedure itself induced only minimal PMN activation. In conclusion, a maximal number of adherent cells, consisting mainly of PMN, was obtained by direct elution with PBS/3 mM EDTA. The method itself did not induce marked PMN activation, and the cells obtained were suitable for further investigations, including flow cytometry.

Biocompatible Materials↗
PubMed1994

The surgical anatomy of the superior gluteal nerve and anatomical radiologic bases of the direct lateral approach to the hip.

In view of the increasing popularity of the direct lateral approach to the hip joint for hemi- or total hip arthroplasty, the location of the superior gluteal nerve (SGN) was studied. This nerve is in danger when using a transgluteal incision. In 20 embalmed specimens the relation of the SGN to the tip of the greater trochanter (TT) was studied as well as the relation to the iliac crest. For this purpose macroscopy, microscopy and CT were used. In 13 hips a so-called most inferior branch was found at an average of 1 cm distal to the inferior branch, the main trunk of the nerve. There was substantial variation in the course of both the inferior and the most inferior branch of the SGN. In order to prevent nerve damage, proximal extension of the transgluteal incision should be limited to 3 cm cranial to TT. Furthermore the incision has to be confined to the distal one third of the distance TT-iliac crest. In tall people extra care should be taken.

Aged↗
PubMed1994

["The Soul-Searchers"--discussion of circulars of the Secret Committee. With a letter by Freud and Rank].

The appearance of Georg Groddeck's novel Der Seelensucher (1921) in the Internationaler Psychoanalytischer Verlag caused a stir among the members of the Secret Committee which, as hitherto unpublished circulars from Committee members testify, then developed into a full-grown controversy. Proceeding from the documents themselves, the author traces the course and the eventual settlement of the difference of opinion over Groddeck's novel. His concern in so doing is not so much to throw light on an episode in the early history of psychoanalysis but rather to take that episode as an instance demonstrating the nature of the discourse mechanisms introduced by Freud to protect the central tenets of his teachings. Bos concludes that these were largely institutional defence mechanisms designed to control the generation of psychoanalytic discourse among the Committee members. In present-day terms, the question arises to what extent psychoanalytic societies and institutions employ such discourse strategies vis-à-vis non-conformists and outsiders.

Freudian Theory↗
PubMed1989

[Congenital hip dislocation; causes and sequelae of late diagnosis].

The causes of late diagnosis of congenital dislocation of the hip were examined retrospectively in a group of 49 children (56 hips affected). It appears that at neonatal examination as well as a further screening during the first year of life, the classical symptoms of this condition are not infrequently missed. The classical tests for the early diagnosis are described and the consequences of late diagnosis are studied. In spite of late detection, the final result of the treatment in most cases is quite favourable. However, this result can only be achieved by prolonged and intensive treatment, including hospitalization and surgery.

Child, Preschool↗
PubMed1988

[Surgical treatment of persistent congenital clubfoot in the young child].

From 1979-1985 seventeen children with twenty-six club-feet were treated. Thirty-four operations have been carried out, divided in three surgical procedures. The heel cord was lengthened in eight feet, a posterior release was done in thirteen feet and a posteromedial release according to Turco was done thirteen times as well. Lengthening of the heel cord seemed to be an insufficient procedure, because six out of eight feet showed a recurrent deformity. The posterior release has given in half of the cases a good result. After posteromedial release we saw in 70% a good or excellent result, when this procedure has been performed between the age of six to twelve months.

Achilles Tendon↗
PubMedDate not supplied

Subtotal mesh-wrapping in the treatment for abdominal aortic aneurysm.

A new technique for managing abdominal aortic aneurysms is described. This so called "subtotal mesh-wrapping" may be considered for high-risk patients with large or growing aneurysms even those extending proximally to the renal arteries. The results in 19 patients, treated by this method, are discussed. Poor general condition renders peri-operative mortality high. But long-term prognosis is improved and with the abandoning of appendectomy will benefit still more.

Aged↗