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J de Vries

Publications and source records attributed to J de Vries.

At least 55 records · Page 3Linked to original sources
PubMed2001

Intraoperative values of S-100 protein, myelin basic protein, lactate, and albumin in the CSF and serum of neurosurgical patients.

OBJECTIVES: To assess the concentrations of S-100 protein, myelin basic protein (MBP), and lactate, and the (CSF)/serum albumin ratio (Qalb) during intracranial neurosurgical procedures. METHODS: Samples of CSF from 91 patients with various CNS diseases were obtained by aspiration of cisternal CSF at the beginning of surgery (before starting surgical manipulation of the brain) and concentrations of S-100 protein, MBP, and lactate, and Qalb were determined. At the same time blood was sampled for determination of serum S-100 protein concentration. Patients were divided into three groups according to the aetiology of their CNS disease (intracranial haemorrhage, n=11; benign intracranial mass lesion, n=52; malignant neoplastic disease, n=28). Radiological and intraoperative characteristics were documented. RESULTS: In each of these three groups median values of all four CSF variables measured were raised. The occurrence of brain oedema and a midline shift correlated significantly with raised concentrations of MBP and Qalb. Breaching of the arachnoid layer, documented at surgery for benign lesions, correlated with higher concentrations of MBP, lactate, CSF S-100 protein, and Qalb. CONCLUSIONS: Intraoperative values of S-100 protein, MBP, lactate, and Qalb are increased in patients with intracranial haemorrhage, benign intracranial mass lesion, and malignant neoplastic disease. Breaching of the arachnoid layer and oedema is associated with higher concentrations of some of the aforementioned proteins. These biochemical data can serve as a basis for further research into CSF specific proteins.

Adolescent↗
PubMed2000

Lymphatic mapping with intralesional tracer administration in breast carcinoma patients.

BACKGROUND: The objectives of the study were to determine how often a sentinel lymph node is visualized by lymphoscintigraphy in breast carcinoma patients, how often the sentinel lymph node is identified during surgery, and the sensitivity of these procedures to identify the presence of axillary lymph node metastasis. METHODS: A total of 136 patients were enrolled in 2 hospitals. Preoperative dynamic and static lymphoscintigraphy were performed; in addition, both a vital dye and a gamma detection probe were used intraoperatively. The tracers were injected into the primary lesion. Sentinel lymph node biopsy was followed by completion axillary lymph node dissection. The sentinel lymph nodes and other axillary lymph nodes were examined routinely and by immunohistochemical staining. RESULTS: A sentinel lymph node was visualized by lymphoscintigraphy in 118 patients (87%). During the operation a sentinel lymph node was localized in 126 patients (93%). A total of 224 sentinel lymph nodes were harvested (average of 1.7 and range of 1-4 sentinel lymph nodes per patient). Of all the sentinel lymph nodes, 37 were blue (17%), 68 were radioactive (30%), and 119 were both blue and radioactive (53%). The sentinel lymph nodes contained metastatic disease in 56 patients (44%). Three sentinel lymph node biopsies were false-negative (sensitivity 95%). CONCLUSIONS: Sentinel lymph node biopsy with preoperative lymphoscintigraphy after intralesional tracer administration and intraoperative use of both a gamma detection probe and a vital dye is a reliable technique for staging the axilla of breast carcinoma patients.

Adult↗
PubMed2000

Direct probing by atomic force microscopy of the cell surface softness of a fibrillated and nonfibrillated oral streptococcal strain.

In this paper, direct measurement by atomic force microscopy (AFM) of the cell surface softness of a fibrillated oral streptococcal strain Streptococcus salivarius HB and of a nonfibrillated strain S. salivarius HBC12 is presented, and the data interpretation is validated by comparison with results from independent techniques. Upon approach of the fibrillated strain in water, the AFM tip experienced a long-range repulsion force, starting at approximately 100 nm, attributed to the compression of the soft layer of fibrils present at the cell surface. In 0.1 M KCl, repulsion was only experienced when the tip was closer than approximately 10 nm, reflecting a stiffer cell surface due to collapse of the fibrillar mass. Force-distance curves indicated that the nonfibrillated strain, probed both in water and in 0.1 M KCl, was much stiffer than the fibrillated strain in water, and a repulsion force was experienced by the tip at close approach only (20 nm in water and 10 nm in 0.1 M KCl). Differences in cell surface softness were further supported by differences in cell surface morphology, the fibrillated strain imaged in water being the only specimen that showed characteristic topographical features attributable to fibrils. These results are in excellent agreement with previous indirect measurements of cell surface softness by dynamic light scattering and particulate microelectrophoresis and demonstrate the potential of AFM to directly probe the softness of microbial cell surfaces.

Biophysical Phenomena↗
PubMed2000

Clinical relevance of sentinel lymph nodes outside the axilla in patients with breast cancer.

BACKGROUND: Lymphatic mapping in patients with breast cancer can reveal sentinel lymph nodes that are not located at level I-II of the axilla. Little is known about the clinical relevance of these nodes. METHODS: Some 113 consecutive patients with clinical stage T1-3 N0 M0 breast cancer were studied. Based on preoperative lymphoscintigraphy, sentinel node biopsy was performed guided by a gamma probe and patent blue dye. All sentinel nodes that were visible on lymphoscintigraphy were sought. Pathological examination of the sentinel nodes included step-sections and staining with CAM 5. 2. Axillary node dissection was performed regardless of sentinel lymph node status. RESULTS: Twenty-one (19 per cent) of 113 patients had sentinel lymph nodes outside level I-II of the axilla, mostly in the internal mammary chain. Twenty-two of the 30 sentinel nodes at these sites were harvested. Three patients had sentinel nodes only outside the axilla. Four other patients had metastases outside the axilla. This changed postoperative treatment in three patients. No postoperative complication occurred. CONCLUSION: Sentinel lymph nodes outside level I-II of the axilla were present in 19 per cent of patients with breast cancer in this series. Biopsy of these nodes was technically demanding but was performed without additional morbidity. The clinical impact was limited; treatment changed in only 3 per cent. Presented to the 52nd annual meeting of the Society of Surgical Oncology in Orlando, Florida, USA, March 1999 and the First International Congress on the Sentinel Node in Diagnosis and Treatment of Cancer in Amsterdam, The Netherlands, April 1999, and published in abstract form as Eur J Nucl Med 1999; 26(Suppl): S71

Adult↗
PubMed2000

Increased killing of Bacillus subtilis on the hair roots of transgenic T4 lysozyme-producing potatoes.

Transgenic potato plants expressing the phage T4 lysozyme gene which are resistant to the plant-pathogenic enterobacterium Erwinia carotovora subsp. carotovora have been constructed. The agricultural growth of these potatoes might have harmful effects on soil microbiota as a result of T4 lysozyme release into the rhizosphere. To assess the bactericidal effect of roots, we have developed a novel method to associate the cells of Bacillus subtilis with hair roots of plants and to quantify the survival of cells directly on the root surface by appropriate staining and fluorescence microscopy. With this technique, we found that the roots of potato plants (Désirée and transgenic control lines) without T4 lysozyme gene display measurable killing activity on root-adsorbed B. subtilis cells. Killing was largely independent of the plant age and growth of plants in greenhouse or field plots. Roots from potato lines expressing the T4 lysozyme gene always showed significantly (1.5- to 3.5-fold) higher killing. It is concluded that T4 lysozyme is released from the root epidermis cells and is active in the fluid film on the root surface. We discuss why strong negative effects of T4 lysozyme-producing potatoes on soil bacteria in field trials may not be observed. We propose that the novel method presented here to study interactions of bacteria with roots can be applied not only to bacterial killing but also to interactions leading to growth-sustaining effects of plants on bacteria.

Adsorption↗
PubMed2000

PCR assessment of Chlamydia trachomatis infection of semen specimens processed for artificial insemination.

In order to ascertain the microbiological quality of stored semen specimens processed for artificial insemination by a donor (AID), we developed a PCR assay targeting the chlamydial plasmid to detect Chlamydia trachomatis in semen. The lower limit of detection of this assay corresponded to 2.5 to 5 elementary bodies per microl of semen. A total of 669 cryopreserved ejaculates from 97 asymptomatic donors were tested for C. trachomatis infection. Twelve ejaculates, originating from four donors, were found to be positive, indicating a 4% prevalence of C. trachomatis infection among the donor population studied. Cross-contamination between the cryopreserved specimens in the storage container was studied by typing using sequence analysis of PCR-amplified omp1 genes of the strains. Two donors were infected with serovar E, one was infected with serovar F, and one was infected with serovar K. For two donors, the duration of C. trachomatis positivity could be assessed. One donor donated C. trachomatis-positive semen for at least 4 successive months, and the other did so for at least 16 months. The occurrence of C. trachomatis infection in cryopreserved donor semen indicates that ejaculates from donors not tested for a C. trachomatis infection just prior to donation should be tested for infection by a direct test such as the PCR described here. Direct testing of semen specimens will detect not only donors with an active infection but also C. trachomatis-infected ejaculates already stored and will thus improve the microbiological quality of AID, since discrepancies in the presence of C. trachomatis in urine and semen specimens have been reported.

Bacterial Outer Membrane Proteins↗
PubMed1999

The Timed "up and go" test: reliability and validity in persons with unilateral lower limb amputation.

OBJECTIVE: To determine the interrater and intrarater reliability and the validity of the Timed "up and go" test as a measure for physical mobility in elderly patients with an amputation of the lower extremity. DESIGN: To test interrater reliability, the test was performed for two observers at different times of the same day in an alternating order. To test intrarater reliability, the patients performed the test for one observer on two consecutive visits with an interval of 2 weeks. To test validity, the results of the Timed "up and go" test were compared with the results on the Sickness Impact Profile, 68-item version (SIP68), and the Groningen Activity Restriction Scale (GARS). PATIENTS: Thirty-two patients, age 60 yrs or older, with unilateral transtibial or transfemoral amputation because of peripheral vascular disease. RESULTS: The Timed "up and go" test showed good intrarater and interrater reliability (r = .93 and .96, respectively). A moderate relationship exists between the Timed "up and go" test and the GARS, a good relationship exists with the "physical subscales" of the SIP68, and there is no relationship with the "mental subscales" of the SIP68. CONCLUSIONS: The Timed "up and go" test is a reliable instrument with adequate concurrent validity to measure the physical mobility of patients with an amputation of the lower extremity.

Activities of Daily Living↗
PubMed1999

Sentinel node biopsy as a surgical staging method for solid cancers.

The sentinel node is the first lymph node that drains a primary tumour. If this lymphatic drainage occurs in a step-wise fashion, this lymph node reflects the pathological status of the remaining lymph node basin. The day before the operation, a total dose of 60 MBq 99mTc nanocolloid is injected around the primary tumour for lymphoscintigraphy. On the day of surgery, 1 ml of blue dye is injected around the primary tumour to facilitate sentinel lymph node detection. After making a small incision over the regional lymph node region, the sentinel node can be detected using a hand-held gamma ray detection probe; the sentinel lymph node and the afferent lymphatic vessels will be stained blue. Sentinel node biopsy has proved useful for malignant melanoma, breast cancer, penile cancer, vulvar cancer, Merkel cell carcinoma and thyroid cancer. New studies are described on breast cancer and malignant melanoma. Gamma-probe-guided localization of radiolabelled lymph nodes can direct the surgeon non-invasively to the exact location of the sentinel node. Once localized with a gamma probe, it is quick and easy to remove the sentinel node through a small incision. Discriminating the node from other tissue can be aided by blue dye which stains the lymph node. It appears that both radioactivity and blue dye are complementary for locating the sentinel node.

Biopsy↗
PubMed1999

Association of fatigue with an acute phase response in sarcoidosis.

The pathophysiological explanation for fatigue, one of the most common symptoms in sarcoidosis, still has to be elucidated. It was hypothesized that the presence of fatigue is associated with an acute phase response in sarcoidosis. A cross-sectional study was performed in 38 sarcoidosis patients. Resting energy expenditure (REE) was measured in the fasting state by indirect calorimetry using a ventilated hood and adjusted for fat-free mass (FFM). Patients with fatigue (n=25) also suffered more frequently from other symptoms, such as exercise intolerance (p=0.01), the need for sleep (p=0.02) and weight loss (p=0.01), compared to those without fatigue (n=13). However, no relationship was found between fatigue and serum angiotensin-converting enzyme (sACE) or lung function impairment. Patients with fatigue had higher levels of C-reactive protein (CRP) (11.4+/-6.8 microg x mL(-1), p<0.0001) and REE adjusted for FFM (33.0+/-3.7 kcal x kg FFM(-1), p<0.003) compared to those without fatigue (3.2+/-2.2 mg x mL(-1); 29.2+/-2.8 kcal x kg FF(-1)). Furthermore, REE/FFM was significantly related to CRP (r=0.54, p=0.001). This study confirms the presence of an acute phase response as indicated by metabolic derangements and a moderate increase in C-reactive protein levels in sarcoidosis, particularly in those patients with constitutional symptoms. Future studies should focus on the clinical relevance and therapeutic implications of these findings.

Acute-Phase Reaction↗
PubMed1999

Subfertile men with constitutive chromosome abnormalities do not necessarily refrain from intracytoplasmic sperm injection treatment: a follow-up study on 75 Dutch patients.

A follow-up study was performed to investigate the impact of the detection of a chromosome abnormality in infertile men who are candidates for intracytoplasmic sperm injection (ICSI) treatment. In this collaborative study between clinical genetics centres and fertility clinics in the Netherlands, 75 ICSI couples of which the male partners had a chromosome abnormality were included. All couples were extensively counselled on the risk of having a chromosomally unbalanced child. Forty-two out of 75 couples chose to proceed with the ICSI treatment. So far, treatment has resulted in a pregnancy in 11 cases. Four of them opted to have invasive prenatal diagnosis. Despite the genetic risks related to a chromosome abnormality in infertile men, a small majority (56%) of the couples did not refrain from the ICSI treatment.

Adult↗
PubMed1999

Differentiation of human single-positive fetal thymocytes in vitro into IL-4- and/or IFN-gamma-producing CD4+ and CD8+ T cells.

In this study we have investigated the capacity of human fetal thymocytes to differentiate in vitro into subsets of T cells with polarized Th1 or Th2 cytokine profiles. Stimulation of freshly isolated human fetal thymocytes with anti-CD3 mAb, cross-linked onto CD32,CD58,CD80-expressing mouse fibroblasts and subsequent culture in the presence of exogenous rIL-2 for 6 days, induced the production of both IL-4 and IFN-gamma, which was mainly produced by CD4+ single-positive (SP) and CD8+ SP cells respectively. Addition of rIL-4 during priming augmented IL-4 production in cultures of human fetal thymocytes, which was mainly due to an increased production of IL-4 by CD8SP cells. In contrast, addition of IL-4 to the cultures only slightly enhanced IL-4 production and had little effect on frequencies of IL-4-producing CD4SP cells. Both CD4SP and CD8SP cells produced IL-5, IL-10 and IL-13 at comparable levels, following priming in the presence of rIL-4. Priming in the presence of rIL-12 strongly enhanced the production of IFN-gamma in both CD4SP and CD8SP cells. No correlation between expression of CD27, CD30 and CD60, and a particular cytokine profile of differentiated thymocytes could be demonstrated. Together, these results demonstrate the full capacity of fetal human thymocytes to differentiate into cytokine-producing T cells in a priming milieu with appropriate stimulatory molecules and exogenous cytokines. In addition, CD4SP thymocytes rapidly differentiate into polarized Th2 cells following stimulation in vitro in the absence of exogenous rIL-4.

Animals↗
PubMed1999

Endoscope-assisted supraorbital craniotomy for lesions of the interpeduncular fossa.

OBJECTIVE: The supraorbital approach is well accepted for lesions in the anterior fossa, the sellar region, and the anterior circle of Willis. However, the usefulness of this approach has not yet been elucidated for lesions in the interpeduncular fossa. The technique of an endoscope-assisted, ipsi- and contralateral supraorbital approach to lesions within the interpeduncular fossa is described, and the initial results are reported. METHODS: A small supraorbital craniotomy, using an eyebrow incision, was performed in each of seven patients who were operated on for different types of lesions in the interpeduncular fossa, including a neuromuscular choristoma of the oculomotor nerve, a retrosellar epidermoid tumor, and five aneurysms (two of the basilar artery tip, two at the offspring of the superior cerebellar artery, and one fusiform arterial widening of the basilar artery apex). The surgical approach, its indications and limitations, and the additional value of an endoscope are outlined. RESULTS: All lesions could be easily reached and well visualized through this approach by using an endoscope as an adjunct to the operating microscope. The saccular aneurysms all could be clipped successfully, the fusiform widening was wrapped, the epidermoid tumor was removed completely, and the choristoma was removed only partially because of brain stem invasion. The patient with the neuromuscular choristoma had persistent diabetes insipidus postoperatively, most probably caused by stretching the pituitary stalk with the endoscope. The patient with the epidermoid tumor showed a postoperative transient partial oculomotor nerve paresis at the side of the approach. The cosmetic results of the eyebrow incisions for this approach were excellent in all patients. CONCLUSION: Lesions in the interpeduncular fossa can be effectively treated using a supraorbital approach, which can be ipsi- or contralateral to the side of the lesion, depending on the exact location of the lesion. The use of an endoscope is essential to visualize these lesions that lie in the shadow of the sellar and parasellar anatomic structures. The major advantage over other approaches are a nearly perpendicular surgical route (although the distance is longer, which is, on the other hand, not a disadvantage), a minimized amount of dissection and brain retraction by using an endoscope through anatomic gateways, and a small surgical incision with excellent cosmetic results.

Adult↗
PubMed1999

The use of Gore-Tex membrane for adhesion prevention in tethered spinal cord surgery: technical case reports.

OBJECTIVE: The incidence of retethering caused by postoperative adhesions at the repair site after initial tethered spinal cord surgery is not uncommon. To assess the effectiveness of a Gore-Tex membrane in preventing these adhesions, only clinical radiological and experimental animal evaluation has been reported. In this report, we describe two cases in which Gore-Tex membrane was implanted at the initial untethering surgery and in which we were able to confirm the real effectiveness of the Gore-Tex membrane during a second operation. METHODS: In the first patient, Gore-Tex membrane was used for dural repair in the untethering surgery of the split spinal cord malformation. Because of the suspicion of a thickened filum terminale, repeated surgery was indicated 10 months after the initial procedure. In the second patient, Gore-Tex membrane was implanted during the initial untethering surgery for a lipomyeloschisis and a dermal sinus. Because of a persistent fistula of the dermal sinus, a second operation was necessary 1 year after the first operation. RESULTS: During the repeated surgery, a thorough inspection of the implanted Gore-Tex membrane revealed no adhesions between the Gore-Tex membrane and the intradural content in both cases. CONCLUSION: We support the use of Gore-Tex membrane in the prevention of postoperative dural adhesions in the repair of spinal dysraphism.

Child, Preschool↗
PubMed1999

Characterization of a dam mutant of Serratia marcescens and nucleotide sequence of the dam region.

The DNA of Serratia marcescens has N6-adenine methylation in GATC sequences. Among 2-aminopurine-sensitive mutants isolated from S. marcescens Sr41, one was identified which lacked GATC methylation. The mutant showed up to 30-fold increased spontaneous mutability and enhanced mutability after treatment with 2-aminopurine, ethyl methanesulfonate, or UV light. The gene (dam) coding for the adenine methyltransferase (Dam enzyme) of S. marcescens was identified on a gene bank plasmid which alleviated the 2-aminopurine sensitivity and the higher mutability of a dam-13::Tn9 mutant of Escherichia coli. Nucleotide sequencing revealed that the deduced amino acid sequence of Dam (270 amino acids; molecular mass, 31.3 kDa) has 72% identity to the Dam enzyme of E. coli. The dam gene is located between flanking genes which are similar to those found to the sides of the E. coli dam gene. The results of complementation studies indicated that like Dam of E. coli and unlike Dam of Vibrio cholerae, the Dam enzyme of S. marcescens plays an important role in mutation avoidance by allowing the mismatch repair enzymes to discriminate between the parental and newly synthesized strands during correction of replication errors.

Cloning, Molecular↗
PubMed1999

Does the cellular bronchoalveolar lavage fluid profile reflect the severity of sarcoidosis?

The aim of this study was to assess whether the cellular bronchoalveolar lavage fluid (BALF) profile, particularly the number of polymorphonuclear neutrophils (PMNs), is associated with disease severity of sarcoidosis and its usefulness in determining remission. Twenty-six nonsmoking outpatients with sarcoidosis were included in this study. The patients were divided into two subgroups according to the absolute number of PMNs in BALF: < or =0.2x10(4) cells x mL(-1) (group 1; n = 15) and >0.2x10(4) cells x mL(-1) (group 2; n = 11). The radiographic stage, high-resolution computed tomography (HRCT) findings, 67Ga lung uptake as well as lung function tests differed significantly between group 1 and 2. Follow-up revealed that 14 (93.3%) patients of group 1 compared to four (36.4%) of group 2 recovered spontaneously without the help of corticosteroids. In contrast, no differences were found in the number of lymphocytes in BALF nor in the serum angiotensin converting enzyme (sACE) level between both groups. The number of PMNs, the transfer factor of the lungs for carbon monoxide (TL,CO), the forced expiratory volume in one second (FEV1) and one of the HRCT subscores discriminated between patients with different disease progression. Of these parameters the PMNs appeared to be the only one which differentiated patients who demonstrated remission and those who deteriorated. In conclusion, these results indicate that the number of polymorphonuclear neutrophils in bronchoalveolar lavage fluid distinguish between sarcoidosis patients who demonstrated remission and those having a more severe course of the disease. Whether polymorphonuclear neutrophils may be considered as markers of disease activity and/or prognosis in sarcoidosis needs further investigation.

Adult↗
PubMed1999

Usability of thenar eminence orthoses: report of a comparative study.

OBJECTIVE: To determine the difference in the usability of three types of thenar eminence (TE) orthoses. DESIGN: Prospective comparative pre-experimental study with randomized cross-over design. SETTING: Rehabilitation centre. SUBJECTS: Ten patients with osteoarthritis of the carpometacarpal I joint confirmed by X-ray. INTERVENTION: Three types of TE orthoses, made of either supple elastic material, elastic material with a semi-rigid thumb busk or a semi-rigid (polyethylene) material. MAIN OUTCOME MEASUREMENTS: Pain at the thenar eminence, pinch force, hand function, cosmesis, comfort and function of the TE orthosis. RESULTS: The supple elastic TE orthosis scores significantly better than the more rigid types on the subjects 'comfort', 'function' and the Green Test, while the semi-rigid orthosis scores best on 'cosmesis'. The score on the subject 'pain reduction' shows no significant difference between the three types of TE orthoses. The scores obtained correspond with the outcome of structured interviews about the usability of the TE orthoses. CONCLUSION: Eight out of 10 patients prefer the permanent use of a TE orthosis. Six patients chose the supple elastic orthosis and two chose the semi-rigid orthosis.

Adult↗
PubMed1999

Transalar sphenoidal encephalocele and respiratory distress in a neonate: a case report.

We present a full-term newborn infant who suffered from immediate postpartum severe respiratory distress. The infant had an inspiratory stridor as a result of a swelling of the soft palate, extending from the roof of the nasopharynx. Transoral endotracheal intubation resulted in normal saturation levels. Histologic examination after an open biopsy showed mature neuroglial tissue. Radiology demonstrated the presence of a right parapharyngeal process obstructing the nasopharynx and oropharynx and extending to the right middle and posterior fossa, via the foramen ovale. After transoral debulking, the infant was extubated successfully. After an uneventful period of 5 months, the patient was readmitted at our hospital for treatment of meningitis. Subsequently, the inspiratory stridor recurred, and staged surgery was performed. First, a transcranial approach was used to remove a large intradural part of the process and close the defect at Meckel's cave. Two weeks later the retro- and parapharyngeal part of the process were removed transorally. Given the site of the defect of the skull base and the intradural location of the process, the diagnosis is a transalar sphenoidal encephalocele. This is a rare type of basal encephalocele, and has never been reported in an infant nor known to present with respiratory distress. The pathogenesis, clinical presentation, pathology, and therapeutic implications of basal encephaloceles are discussed.

Encephalocele↗