Biomedical subjects

T De Baere

Publications and source records attributed to T De Baere.

At least 19 recordsLinked to original sources

PubMed2006

Chemoembolization for liver metastases from medullary thyroid carcinoma.

BACKGROUND: Medullary thyroid carcinoma (MTC) is a well-differentiated neuroendocrine tumor. Distant metastases are the main cause of cancer-related death. Systemic chemotherapy produces only rare tumor responses. Somatostatin analogs and other available modalities are poorly effective to control symptoms. AIMS: The aim of our study was to evaluate the impact of liver transarterial chemoembolization (TACE) in MTC patients with predominant and progressive liver metastases. PATIENTS AND METHODS: Twelve MTC patients underwent 18 TACE courses (mean, 1.5; range, 1-2). Response evaluation criteria in solid tumors were used to evaluate tumor responses. Symptomatic responses were defined by more than a 25% decrease of symptoms intensity. RESULTS: Partial radiological tumor response was obtained in five patients (42%) with a median duration of 17 months (mean, 19; range, 15-28 months), stabilization in five (42%) with a median duration of 24 months (mean, 24; range, 4-39 months), and progression in the remaining two (16%). The five partial tumor responses were observed in the nine patients with less than 30% liver involvement. Clinical response was observed in two of the five patients with diarrhea. Carcinoembryonic antigen did not appear to be a useful marker in this setting. Significant grade 3-4 toxicity was observed in one patient who had a major tumor necrosis after TACE. CONCLUSION: TACE should be considered for treating MTC patients with progressive and predominant liver metastasis, and preferably at an early stage during the course of metastatic disease.

Adult↗

PubMed2006

Direct identification of bacteria in clinical respiratory samples using fluorescent amplicon length analysis of 16S-23S rRNA spacer-region.

We describe the development and application of a rapid and universal molecular technique for direct identification of multiple bacteria in clinical samples. Amplification of the 16S-23S rRNA spacer-region using universal primers led to fragment patterns distinct for different bacterial species and that were analyzed with fluorescent amplicon length analysis (FALA). 136 pure cultures of clinical isolates and 20 culture collection strains belonging to 22 different medically important species were used to create a primary database of fragments with sizes between 100 and 1000 bp. Subsequently, 127 respiratory samples were analyzed with culture-based techniques and via FALA of the 16S-23S rRNA spacer-region. Two DNA extraction methods were evaluated: Instagene (FALA-I) and Fastprept (FALA-P). Of the 127 samples, 26 culture-negative samples were also negative with FALA-P. Of 18 samples with growth of commensal oral flora, 10 gave a mixed oral flora pattern with FALA-P and 8 gave a negative result. For 54 samples with growth of a single bacterial species, FALA-P gave an identical result for 46. For 29 samples with growth of more than one bacterial species, identical results were obtained in 19 samples. False-negative results with FALA-P were mostly due to paucity (less than 10(3) CFU/ml) of bacteria (12 out of 18 false-negatives) or difficulties with homogenization of viscous samples (6 out of 18 false-negatives).With regard to identification of all significant pathogens of clinical samples tested, the sensitivity of FALA-P was 77% and its specificity was 100%. With FALA-I, the number of false-negative results was higher than with FALA-P due to less efficient extraction of DNA, particularly with Staphylococcal species. FALA-P allows rapid and direct identification of multiple species directly from clinical samples; pauci-cellular samples may give false-negative results.

Bacteria↗

PubMed2006

Hyperselective intra-arterial preoperative chemotherapy in patients with squamous cell carcinoma of the oral cavity: preliminary results.

OBJECTIVES: To investigate radiological response and findings after Intra Arterial Chemotherapy (IAC) for patients with Squamous Cell Carcinoma (SCC) of the oral cavity. MATERIALS AND METHODS: Patients received 1-2 cycles of IAC. Radiological assessment was performed on day 7 and day 21 after each cycle using CT scan and MRI. RESULTS: Six patients (median age: 52, ranging 46-60; male/female: 5/1) received 10 cycles (4 patients received 2 cycles). Primary tumors were floor of the mouth (4 patients) and oral tongue (2 patients). TNM classification was T2N0-2b in 3 patients and T4N0-1 in 3 patients. All patients had good locoregional/systemic tolerance and 3 showed clinical objective response (OR). Four patients were evaluable on both CT and MRI, 1 patient on MRI only and 1 patient did not tolerate imaging. Three patients showed OR both on CT and MRI, 1 patient showed stable disease (SD) on CT and OR on MRI and 1 patient showed SD on MRI. Contrast-enhancement of hemiperfused tongue was reported in all evaluable patients. Two patients presented intratumoral necrosis and 5 patients displayed local edema (MRI). One patient had modification of the sternocleidomastoid muscle after IAC. CONCLUSION: Radiological modifications were observed in the infused area and correlated well with clinical response. This study is ongoing.

Antineoplastic Agents↗

PubMed2003

First report on Cryptococcus laurentii associated with feather loss in a glossy starling (Lamprotornis chalybaeus).

Although Cryptococcus laurentii has been isolated from fresh droppings and cloaca samples from feral pigeons, it has never before been associated with an actual disease condition in birds. This case study deals with the first report on C. laurentii associated with feather loss in a glossy starling (Lamprotornis chalybaeus). The bird exhibited patchy feather loss, especially around the back and beak area, and greyish crusts sticking quite firmly to the underlying skin. The feathers had a greasy appearance and disseminated a musty odour. Treatment was installed with fluconazole in the drinking water. One month following the onset of treatment, the condition of the plumage had markedly improved.

Animals↗

PubMed2002

Identification of a new biotype of Actinomyces hyovaginalis in tissues of pigs during diagnostic bacteriological examination.

Bacterial strains isolated from a large variety of necropsy samples of pigs and previously described as a phenotypical homogeneous group were shown to belong to the species Actinomyces hyovaginalis. This was unexpected because their colonial characteristics, as well as their origins, were very different from those originally reported for the vaginal strains on which the species description of A. hyovaginalis was based. Colonial morphology, as well as fermentation of cellobiose, reactions in hippurate and nitrate and production of beta-glucuronidase, allowed separation of the strains studied here from the vaginal strains. Analysis of tRNA intergenic length polymorphisms (tDNA-PCR), 16S rRNA-gene sequencing and DNA-DNA hybridizations were carried out and led to the proposal of a separate biotype within the species A. hyovaginalis. Since, the strains were isolated from different body sites, this biotype has been designated as the 'general' biotype of A. hyovaginalis, while the strains on which the original species description was based are designated as the 'vaginal' biotype.

Actinomyces↗

PubMed2002

Percutaneous radiofrequency thermoablation as an alternative to surgery for treatment of liver tumour recurrence after hepatectomy.

BACKGROUND: Radiofrequency (RF) current, converted into heat through ion agitation and friction, can destroy liver tumours by means of coagulation necrosis. This study assessed whether percutaneous RF ablation is a useful and safe technique for the treatment of liver tumour recurrence after hepatectomy. METHODS: Forty-seven patients presenting with local recurrence after hepatectomy for malignant tumours (29 with colorectal secondaries) were treated with percutaneous RF ablation instead of repeat hepatectomy. RF thermal ablation was performed under image guidance for 12-15 min. This group represented 63 per cent of 75 patients treated with curative intent for liver recurrence in the same time interval. The other 28 patients underwent repeat hepatectomy. RESULTS: The mean(s.d.) number of liver metastases destroyed was 1.4(0.7) (range 1-3) and their diameter was 21(8) (range 9-35) mm. Twenty-six patients presented with liver recurrence at least once but up to three times after the initial RF application. Incomplete local RF treatment was observed in six of 47 patients. Fifteen patients developed extrahepatic recurrence. The mean(s.d.) interval between RF ablation and the last follow-up visit was 14.4(10.1) (range 5.5-40) months. One death and three major complications occurred. Survival rates at 1 and 2 years were 88 and 55 per cent respectively. A retrospective study of the authors' database over two similar consecutive periods showed that RF ablation increased the percentage of curative local treatments for liver recurrence after hepatectomy from 17 to 26 per cent and decreased the proportion of repeat hepatectomies from 100 to to 39 per cent. CONCLUSION: Percutaneous RF treatment increases the number of patients eligible for curative treatment. It should be preferred to repeat hepatectomy when feasible and safe because it is less invasive. Repeat hepatectomy is indicated only when percutaneous RF ablation is contraindicated or fails.

Adolescent↗

PubMed2002

[Biliary and vascular anatomy of the liver].

This paper is a review of the anatomy of the bile ducts and the vascular anatomy of the liver. This anatomy is subject of numerous variations which can be explained by the embryology of the liver and its vessels. The perfect knowledge of this anatomy is useful for an accurate interpretation of the conventional and slice imaging techniques of the liver. It is also of major importance for an appropriate management of all kinds of hepatic vascular and biliary percutaneous procedures.

Bile Ducts, Intrahepatic↗

PubMed2002

Functional results after surgical repair of quadriceps tendon rupture.

We present the long-term results of surgical repair of a traumatic rupture of the quadriceps tendon in a group of 24 patients with a mean age of 58 years. There were 21 male and 3 female patients. Fifteen patients were seen for clinical control after a mean follow-up of 75 months and they all presented with some quadriceps muscle atrophy. Twelve patients had normal knee mobility, three had a flexion deformity of 10 degrees and two had less than 120 degrees of knee flexion. Active knee extension was normal in all patients. Three patients experienced some decrease in stability of their knee joint. Subjectively all patients were satisfied with the result. Nine patients underwent a Cybex-test for evaluation of the isokinetic force of knee flexion and extension, with a comparison between the injured and the uninjured side. For concentric force there was a mean deficit at low speed of 36.1% for the quadriceps muscle; at high speed it was 28.2%. For the knee flexors, the deficits were 30.7% and 27.2% respectively. Regarding eccentric force, the mean deficit for knee extensors was 13.8% and 0.25% respectively and for knee flexors 6.5% and 5.5% respectively.

Adolescent↗

PubMed2001

Detection of Actinobacillus pleuropneumoniae in cultures from nasal and tonsillar swabs of pigs by a PCR assay based on the nucleotide sequence of a dsbE-like gene.

A PCR assay for the detection of Actinobacillus pleuropneumoniae was developed based on the amplification of a dsbE-like gene. All of 157 field isolates of A. pleuropneumoniae reacted in the PCR by the amplification of a 342bp product. No reaction was observed with related bacterial species or other bacterial species isolated from pigs, except for A. lignieresii. The lower detection limit of the PCR was 10(2) CFU per PCR test tube and was not affected by the addition of 10(6) CFU Escherichia coli. The PCR was evaluated on mixed bacterial cultures from nasal and tonsillar swabs as well as suspensions of nasal conchae and tonsils obtained from specific pathogen-free (SPF) pigs, experimentally infected pigs, and pigs from farrow-to-finish herds. The results of the new PCR were compared with a PCR based on the detection of the omlA gene coding for an outer membrane protein, with a commercially available PCR (Adiavet APP, Adiagène, Saint-Brieuc, France), and with conventional culturing. No positive reactions were observed with any of the PCR methods in samples of SPF animals. In samples of the other animals, no or low significant differences between nasal swabs and suspensions as well as tonsillar swabs and suspensions were observed in any method. In general, more positive results were obtained from tonsillar samples in comparison to nasal samples. Interassay sensitivity and specificity values were assessed for each test by pair wise comparisons between assays. The agreement between tests was evaluated by calculating Cohen's kappa coefficient. From these analyses the three PCR assays showed a good agreement. The dsbE-based PCR proved to be highly sensitive (95 and 93%) and specific (82 and 74%) in comparison to the omlA-based PCR and the commercially available PCR, respectively. It was concluded that the dsbE-like gene-based PCR is a reliable diagnostic assay for demonstration of A. pleuropneumoniae. Furthermore, it was demonstrated that tonsillar swabs can be used for the detection of the pathogen in healthy carrier animals.

Actinobacillus Infections↗

PubMed2001

Radio-frequency tissue ablation of the liver: effects of vascular occlusion on lesion diameter and biliary and portal damages in a pig model.

The aim of this study was to assess the effect of vascular occlusion on radio-frequency (RF) lesion size and on potential associated biliary and portal lesions. Radio-frequency lesions using a 1-cm exposed-tip cooled electrode were created in pig liver. Liver perfusion was modified by arterial embolization (n=2), left portal clamping (n=2), and both (n=2). Two pigs were used as controls. Two weeks after, control portography was performed, animals were killed, and ex-vivo cholangiography was carried out. Pathological studies evaluated the lesion surface and associated portal and biliary damages. A mathematical regression model showed that portal occlusion increased by 43 mm2 (+40%) the surface of RF lesions, arterial occlusion by 135 mm2 (+126%), and associated occlusion by 466 mm2 (+435%). Biliary stenoses were found in 4 cases (two arterial occlusions, one portal occlusion, and one associated occlusion). One case of partial portal vein thrombosis was found in one case of portal occlusion and resolved at 2 weeks. Ischemic damages adjacent to RF lesions were found in cases of combined occlusions. The reduction of liver perfusion increases significantly the size of RF lesions but is associated with a risk of biliary, portal, or parenchymal complications.

Animals↗

PubMed2001

Antitumour activity of somatostatin analogues in progressive metastatic neuroendocrine tumours.

A few studies have suggested an antitumour activity of somatostatin analogues in neuroendocrine tumours (NET). The aim of this study was to evaluate the antitumour efficacy of somatostatin analogues in patients with documented progressive tumours. 35 consecutive patients with documented tumour progression were treated with somatostatin analogues. Patients were classified into two groups. In Group 1, tumours were progressing rapidly (an increase of 50% or more in the lesion surface area in 3 months) and in Group 2, tumours were progressing more slowly (an increase of less than 50% in the lesion surface area in 3 months but greater than 25% in 6 months). Treatment consisted of subcutaneous (s.c.) octreotide, 100 microg thrice daily for 17 patients, intramuscular lanreotide, 30 mg/every 14 days for 11 patients and for 7 patients both somatostatin analogues were used successively during the follow-up. Primary tumour sites were the small intestine (n=12), pancreas (n=13), lungs (n=5), and other sites (n=5). 18 patients had the carcinoid syndrome with flushing and/or diarrhoea. The median duration of treatment was 7 months. Treatment was discontinued in 3 patients due to side-effects. One patient (3%) achieved a partial response and the disease was stabilised in 20 patients (57%) for a median duration of 11 months (6-48 months). Stabilisation of patients in Group 1 was significantly less frequent at 6 months than that of patients in Group 2 (4/12 and 13/17 respectively, P<0.02). Somatostatin analogue treatment resulted in one partial response (3%) and 20 cases of stabilisation (57%) in 35 patients with progressive NET. A slow tumour growth rate before treatment is predictive of a good response to somatostatin analogues which could be considered an option for first-line treatment.

Adult↗

PubMed2001

Evaluation of six commercial assays for the rapid detection of Clostridium difficile toxin and/or antigen in stool specimens.

OBJECTIVE: To evaluate six commercially available assays for the detection of Clostridium difficile toxin and/or antigen in stool samples: one latex agglutination test (Culturette brand CDT, Becton Dickinson), two ELISAs (Culturette brand Toxin CD, Becton Dickinson, and Ridascreen C. difficile Toxin A/B, R-biopharm), two chromatographic assays (Clearview C. difficile A, Oxoid, and ColorPac Toxin A, Becton Dickinson) and one enzyme immunoassay for the simultaneous detection of C. difficile common antigen and toxin A (Triage C. difficile Panel, Biosite). METHODS: Over a period of 3 months, 366 liquid or semi-liquid stool samples were tested using cell-culture cytotoxin assay as standard, ethanol shock stool culture and latex agglutination (Culturette brand CDT). Of these, 78 samples, positive with at least one of these three methods, and 98 randomly selected negative samples were further evaluated using the other five kits. PCR was also performed on positive cultures to confirm the presence of toxin A and B genes. RESULTS: Triage C. difficile Panel had the best sensitivity (95%), followed by Clearview C. difficile and ColorPac Toxin A (both 89%), Culturette brand Toxin CD (73%), Ridascreen C. difficile Toxin A/B (57%) and Culturette brand CDT (23%). For Triage, the sensitivity of C. difficile antigen detection was 93%, and the sensitivity of toxin detection was lower (77%). Most false-positive results were obtained with the Triage C. difficile Panel (25 specimens) and Clearview C. difficile A (20 specimens). Culturette brand CDT had the best specificity (99%); followed by Ridascreen C. difficile Toxin A/B (97%), Culturette brand Toxin CD (95%), ColorPac Toxin A (89%), Clearview C. difficile A (83%) and Triage C. difficile Panel (75%). The positive predictive values ranged from 68% to 94%, and the negative predictive values from 83% to 98%. CONCLUSIONS: The sensitivity is much higher for Triage and the two new chromatographic assays than for the conventional EIAs. These tests also have a high negative predictive value. For Triage, C. difficile antigen-positive, toxin A-negative results can be obtained; the clinical value of these must be established by additional studies. Overall, the new-generation assays are still less sensitive than the cytotoxin assay; however, they provided same-day results, could be used as a screening test and may be useful in laboratories without tissue-culture facilities. Our results do not allow the recommendation of one single assay for the diagnosis of C. difficile-associated diarrhea. It remains the case that laboratory results must be correlated and interpreted with the clinical presentation of the patient.

Antigens, Bacterial↗

PubMed2001

Evaluation of contrast-enhanced color Doppler ultrasound for the quantification of angiogenesis in vivo.

RATIONALE AND OBJECTIVES: To evaluate contrast-enhanced color Doppler ultrasonography (CDUS) aimed at quantifying angiogenesis in vivo. METHODS: Eight colon tumors xenografted into mice were studied with CDUS both without and after injection of SHU 508A. The number of intratumor vessels and pedicles visualized with CDUS and the value of the acoustic intensity quantified by computer were compared with the evaluation of angiogenesis by study of digitized histological slides. RESULTS: SHU 508A increased the number of intratumor vessels and pedicles depicted by CDUS, which could also be quantified by acoustic intensity. The comparison of CDUS and digitized histological slide studies showed that the detection threshold after SHU 508A administration allowed visualization of small vessels (40 microm in diameter). The "hot spots" seen on histology were superimposable onto vessels seen with CDUS. Regions in which no vessels were detected by CDUS corresponded to regions in which vascularization was absent by histological analysis. CONCLUSION: Injection of SHU 508A significantly increased vessel detection with CDUS.

Animals↗

PubMed2001

Classification of Ralstonia pickettii biovar 3/'thomasii' strains (Pickett 1994) and of new isolates related to nosocomial recurrent meningitis as Ralstonia mannitolytica sp. nov.

Strains isolated independently from two patients could be recognized as Ralstonia pickettii biovar 3/'thomasii'. The 16S rDNA sequences of these strains and two other strains of R. pickettii biovar 3/'thomasii' clustered at less than 98% similarity versus all other described Ralstonia species and at less than 97 % versus the two other R. pickettii biovars. The separate species status of R. pickettii biovar 3/'thomasii' was confirmed by DNA-DNA hybridization, indicating less than 60% DNA homology with the R. pickettii biovars Va-1 and Va-2 and with two as-yet unclassified but biochemically similar Ralstonia strains. Phenotypically, this Ralstonia species can be distinguished from all described Ralstonia species by its acidification of D-arabitol and mannitol and by its lack of nitrate reduction and of alkalinization of tartrate and from two as-yet unclassified Ralstonia strains only by its lack of nitrate reduction. The name Ralstonia mannitolytica sp. nov. is proposed, reflecting the characteristic acidification of mannitol. Resistance to desferrioxamine is another difference from R. pickettii and Ralstonia solanacearum. Although several nosocomial outbreaks have been associated with R. mannitolytica, life-threatening infections have not yet been reported, possibly due to misidentification as Pseudomonas fluorescens or Burkholderia cepacia. In at least one of the two cases reported here, the R. mannitolytica isolate was found to be clinically relevant, causing recurrent nosocomial meningitis, with an infected implanted catheter as the source. The type strain of R. mannitolytica is NCIMB 10805T (= LMG 6866T), which was isolated during the first described outbreak as 'Pseudomonas thomasii' at St Thomas' Hospital, London, UK, in 1971.

Base Composition↗

PubMed2001

Acinetobacter ursingii sp. nov. and Acinetobacter schindleri sp. nov., isolated from human clinical specimens.

The taxonomic status of two recently described phenetically distinctive groups within the genus Acinetobacter, designated phenon 1 and phenon 2, was investigated further. The study collection included 51 strains, mainly of clinical origin, from different European countries with properties of either phenon 1 (29 strains) or phenon 2 (22 strains). DNA-DNA hybridization studies and DNA polymorphism analysis by AFLP revealed that these phenons represented two new genomic species. Furthermore, 16S rRNA gene sequence analysis of three representatives of each phenon showed that they formed two distinct lineages within the genus Acinetobacter. The two phenons could be distinguished from each other and from all hitherto-described Acinetobacter (genomic) species by specific phenotypic features and amplified rDNA restriction analysis patterns. The names Acinetobacter ursingii sp. nov. (type strain LUH 3792T = NIPH 137T = LMG 19575T = CNCTC 6735T) and Acinetobacter schindleri sp. nov. (type strain LUH 5832T = NIPH 1034T = LMG 19576T = CNCTC 6736T) are proposed for phenon 1 and phenon 2, respectively. Clinical and epidemiological data indicate that A. ursingii has the capacity to cause bloodstream infections in hospitalized patients.

Acinetobacter↗

PubMed2001

Case of catheter sepsis with Ralstonia gilardii in a child with acute lymphoblastic leukemia.

Acute lymphoblastic leukemia was diagnosed in a 7-year-old girl. Two months after insertion of a central venous catheter, she developed fever and complained of headache and abdominal pain. Physical examination revealed no focus of infection. A gram-negative nonfermenting bacillus was recurrently cultured from blood. Extensive biochemical testing and 16S ribosomal DNA sequencing led to the identification of Ralstonia gilardii.

Bacteremia↗

PubMed2001

One case each of recurrent meningitis and hemoperitoneum infection with Ralstonia mannitolilytica.

Two clinical cases of infection with Ralstonia mannitolilytica are described: a recurrent meningitis on an implanted intraventricular catheter and an infected hemoperitoneum as a complication of a cholangiocarcinoma. The strains were first misidentified as Pseudomonas fluorescens and Burkholderia cepacia. Further testing lead to the identification as Ralstonia pickettii biovar 3/"thomasii," which was recently shown to represent a separate species, R. mannitolilytica (List editor N. Weiss, Int. J. Syst. Evol. Microbiol. 51:795-796, 2001), originally described as R. mannitolytica (De Baere et al., Int. J. Syst. Evol. Microbiol. 51:547-558, 2001). R. mannitolilytica can be distinguished from all described Ralstonia species by its acidification of D-arabitol and mannitol and by its lack of nitrate reduction and of alkalinization of tartrate. In order to determine the true prevalence of infections with this species, colistin-resistant "P. fluorescens" strains and strains growing on B. cepacia selective medium deserve further attention.

Adult↗

PubMed2001

Mycobacterium interjectum as causative agent of cervical lymphadenitis.

A mycobacterial strain isolated from a lymph node of a 3-year-old female with cervical lymphadenitis was identified as Mycobacterium interjectum by means of sequencing of the 16S rRNA gene. Analysis of this case and previously published cases demonstrates the importance of M. interjectum as a causative agent of cervical lymphadenitis in young children.

Child, Preschool↗