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P Delaere

Publications and source records attributed to P Delaere.

At least 19 recordsLinked to original sources
PubMed1998

Serum parathyroid hormone and calcium during the first days after resection of a parathyroid adenoma.

Serum parathyroid hormone, calcium and phosphate were daily monitored in 12, 30 and 30 patients respectively during the early postoperative period after removal of a solitary parathyroid adenoma. In all patients PTH concentration dropped to very low values on the first postoperative day, whereafter a rapid recovery began. So the first day is the best time to evaluate the results of the intervention. Hypocalcemia was most frequent on the third day. After ten days 26 patients showed a normal calcemia, while 4 patients still had a mild hypocalcemia (8-8.8 mg/dl). These data may guide management of patients after parathyroid surgery.

Adenoma↗
PubMed1998

Prospective randomized comparative study of tracheoesophageal voice prosthesis: Blom-Singer versus Provox.

OBJECTIVES: Compare the most commonly used types of tracheoesophageal voice prostheses, Blom Singer and Provox. STUDY DESIGN: Prospective study of 113 prostheses placed in 52 patients randomly selected to receive Blom-Singer and Provox. METHODS: Postoperative voice was recorded at 1 and 4 months after valve placement. Survival time of the prosthesis and four objective voice parameters were analyzed. Eight judges rated all recordings in a random order for six subjective voice parameters. Subgroup analysis for primary versus secondary placements and type of procedure was performed. In addition, patients were asked for their subjective assessment. RESULTS: Overall, Blom-Singer and Provox prostheses give very similar voice quality, lifetime, and patient satisfaction. Cleaning management is somewhat better for Provox, but there is a trend toward better overall voice quality for the Blom-Singer prosthesis. In subgroup analysis secondarily placed prostheses score somewhat better than primary placements, and patients with total laryngectomy have better voices than patients with extended laryngectomy combined with partial pharyngectomy. CONCLUSIONS: Given the equal and good results in terms of voice quality, other factors (e.g., costs, surgery-related factors, maintenance, patient preference) should be taken into account when deciding which type of tracheoesophageal voice prosthesis to use.

Esophagus↗
PubMed1997

Acoustic analysis of the speaking voice after thyroidectomy.

Voices of 47 female patients were analyzed before and after thyroidectomy, with preservation of the recurrent and superior laryngeal nerves and normal vocal fold motility during the observation period. A mean decrease of the speaking fundamental frequency (SFF) of 12 Hz was found on day 4; in 8 patients the postoperative vocal pitch was more than 2 semitones lower. The distance between the highest and lowest F0 during speaking was diminished (speech was more monotone) and the vocal jitter was elevated. In the frequency spectrum, there was a diminished prominence of the harmonics. The other spectral parameters (as the slope of the spectrum and the H1/H2 ratio) were unchanged. All changes had disappeared the fifteenth day, except for a lower SFF (> 2 semitones) in 2 cases. It is concluded that after normal dissection of the laryngeal nerves, and in the absence of vocal fold paresis, other reasons for voice changes immediately after thyroidectomy remain: alterations in the neck muscles, in the laryngeal mucosa, and in the patient's general condition. Although the effects seem limited and of short duration, knowledge of them is helpful when informing the patient before thyroid surgery.

Female↗
PubMed1997

Distribution of the solitary adenoma over the parathyroid glands.

One hundred and ten patients with primary hyperparathyroidism were studied, in which a normal parathyroid gland was found on the same side as an adenoma (both confirmed by histological examination), and the upper or lower location could clearly be defined during surgery. The distribution of the adenomas over the upper and lower glands was unequal: 61.8 per cent in the superior versus 38.2 per cent in the inferior position. Statistical analysis revealed that this is not a random distribution (p = 0.013). The explanation of this relative predilection is unknown. The finding should not influence the surgical procedure for primary hyperparathyroidism.

Adenoma↗
PubMed1997

Long-term gene delivery into the livers of immunocompetent mice with E1/E4-defective adenoviruses.

We have compared the in vitro and in vivo behaviors of a set of isogenic E1- and E1/E4-defective adenoviruses expressing the lacZ gene of Escherichia coli from the Rous sarcoma virus long terminal repeat. Infection of tumor-derived established cell lines of human origin with the doubly defective adenoviruses resulted in (i) a lower replication of the viral backbone that correlated with reduced levels of E2A-specific RNA and protein, (ii) a significant shutoff of late gene and protein expression, and (iii) no apparent virus-induced cytotoxicity. Independently of the extent of the deletion, the additional inactivation of E4 from the viral backbone therefore drastically disabled the virus in vitro, with no apparent effect on transgene expression. A lacZ-transgenic model was used to compare the different recombinant adenoviruses in the livers of C57BL/6 mice. The immune response to the virally encoded beta-galactosidase was minimal in this model, as infusion of the E1-defective adenovirus resulted in a time course of transgene expression that mimicked that in immunodeficient (nu/nu) mice, with very little inflammation and necrosis in the liver. Administration of a doubly defective adenovirus to the transgenic animals led to long-term extrachromosomal persistence of viral DNA in the liver, with no detectable methylation of CpG dinucleotides. However, transient transgene expression was observed independently of the extent of the E4 deletion, suggesting that the choice of the promoter may be critical to maintain transgene expression from these attenuated adenovirus vectors.

Adenoviridae↗
PubMed1997

Quality of life in head and neck cancer patients.

In recent years the number of Quality of Life (QOL) studies has increased rapidly. When evaluating outcomes of clinical trials in patients, one should take into consideration QOL aspects in addition to the well-known standard biomedical endpoints. The difficult question is how to select the best instrument from the flood of papers. A review and a few reflections are presented.

Attitude to Health↗
PubMed1997

Temporary voice changes after uncomplicated thyroidectomy.

Voice characteristics were studied before and after thyroidectomy in patients with intact vocal fold motility. The speaking voice was acoustically analysed in 47 patients and phonetograms were made in 17 patients. Eight parameters were measured and the pre- and postoperative values compared. The results show that the most affected parameter was the pitch of the speaking voice. The fourth postoperative day there was, on average, a lower SFo and a smaller Fo range during speaking. Postoperatively a progressive normalisation took place. After three months there were no more statistical differences and, looking at the individual measures, the SF0 of all patients fell within 2 semitones from their preoperative level. Vocal quality was also altered in the first postoperative examination, as shown by the higher jitter and smaller harmonics. These measures normalised after two weeks. In the same way, the evaluation of the limits of the voice by means of the phonetogram, showed that the maximal performances in the intensity and pitch domain were decreased in the earliest postoperative period. Information about temporary voice change is useful in patients undergoing thyroidectomy.

Female↗
PubMed1997

Characterization of new polyclonal antibodies specific for 40 and 42 amino acid-long amyloid beta peptides: their use to examine the cell biology of presenilins and the immunohistochemistry of sporadic Alzheimer's disease and cerebral amyloid angiopathy cases.

BACKGROUND: In Alzheimer's disease (AD), the main histological lesion is a proteinaceous deposit, the senile plaque, which is mainly composed of a peptide called A beta. The aggregation process is thought to occur through enhanced concentration of A beta 40 or increased production of the more readily aggregating 42 amino acid-long A beta 42 species. MATERIALS AND METHODS: Specificity of the antibodies was assessed by dot blot, Western blot, ELISA, and immunoprecipitation procedures on synthetic and endogenous A beta produced by secreted HK293 cells. A beta and p3 production by wild-type and mutated presenilin 1-expressing cells transiently transfected with beta APP751 was monitored after metabolic labeling and immunoprecipitation procedures. Immunohistochemical analysis was performed on brains of sporadic and typical cerebrovascular amyloid angiopathy (CAA) cases. RESULTS: Dot and Western blot analyses indicate that IgG-purified fractions of antisera recognize native and denaturated A beta s. FCA3340 and FCA 3542 display full specificity for A beta 40 and A beta 42, respectively. Antibodies immunoprecipitate their respective synthetic A beta species but also A beta s and their related p3 counterparts endogenously secreted by transfected human kidney 293 cells. This allowed us to show that mutations on presenilin 1 triggered similar increased ratios of A beta 42 and its p 342 counterpart over total A beta and p3. ELISA assays allow detection of about 25-50 pg/ml of A beta s and remain linear up to 750 to 1500 pg/ml without any cross-reactivity. FCA18 and FCA3542 label diffuse and mature plaques of a sporadic AD case whereas FCA3340 only reveals the mature lesions and particularly labels their central dense core. In a CAA case, FCA18 and FCA3340 reveal leptomeningeal and cortical arterioles whereas FCA3542 only faintly labels such structures. CONCLUSIONS: Polyclonal antibodies exclusively recognizing A beta 40 (FCA 3340) or A beta 42 (FCA3542) were obtained. These demonstrated that FAD-linked presenilins similarly affect both p342 and A beta 42, suggesting that these mutations misroute the beta APP to a compartment where gamma-secretase, but not alpha-secretase, cleavages are modified. Overall, these antibodies should prove useful for fundamental and diagnostic approaches, as suggested by their usefulness for biochemical, cell biological, and immunohistochemical techniques.

Alzheimer Disease↗
PubMed1996

Trisomy 3 in marginal zone B-cell lymphoma: a study based on cytogenetic analysis and fluorescence in situ hybridization.

Trisomy 3 represents the most frequent and consistent chromosomal abnormality characterizing the recently defined entity marginal zone B-cell lymphoma (MZBCL). By cytogenetic analysis and/or fluorescence in situ hybridization (FISH) on interphase nuclei we found in increased copy number of chromosome 3 in 22/36 (61%) successfully analysed cases, including 8/12 cases with extranodal MZBCL, 8/13 cases with nodal MZBCL, and 6/11 patients with splenic MZBCL. Sensitivity of interphase cytogenetics was somewhat higher than that of conventional cytogenetic investigation. Structural chromosomal changes involving at least one chromosome 3 were seen in 11/20 cases with an increased copy number of chromosome 3: +de(3)(p13) was demonstrated in three cases, and was the sole chromosomal abnormality in one of them; +i(3)(q10) was seen in two other patients; and rearrangements involving various breakpoints on the long arm of chromosome 3 were found in the remaining cases. FISH on metaphase spreads confirmed these structural abnormalities and additionally showed two unexpected translocations involving chromosome 3. We conclude that: (1) trisomy 3 occurs in a high proportion of extranodal, nodal and splenic MZBCL; (2) FISH on interphase nuclei is an additional and sensitive tool in detecting an increased copy number of chromosome 3 in MZBCL; (3) additional structural abnormalities involving the long arm of chromosome 3 are frequent but non-recurrent and are perhaps secondary changes; and (4) abnormalities such as +del(3)(pl3) and +i(3)(q10) suggest that genes located on the long arm of chromosome 3 are of particular importance in the pathogenesis of MZBCL.

Adult↗
PubMed1996

The effects of thymostimulin on immunological function in patients with head and neck cancer.

Patients with head and neck carcinoma show deficits of cellular immunity, probably due to low molecular mass factors (LMMFs) released by the tumour. Thymostimulin (TP1) restores the defective monocyte chemotaxis and dendritic cell clustering capability in the presence of the tumour when administered pre-operatively. In the present study we investigated these immune parameters in 39 patients treated with TP1 for 10 days pre- and 6 months post-operatively and in 22 patients who were not treated with TP1 for 6 months after operation. Removal of the tumour in non-TP1-treated patients also resulted in a restoration of monocyte and dendritic cell functions, while TP1 treatment gave no additional effect. LMMF levels in the blood of both TP1-treated and non-TP1-treated patients remained elevated even after removal of the tumour, and it is therefore concluded that it is unlikely that depression of cellular immunity is a direct effect of these LMMFS.

Adjuvants, Immunologic↗
PubMed1995

Glutamine synthetase (GS) expression is reduced in senile dementia of the Alzheimer type.

Glutamine synthetase (GS), a metabolic marker of the mature astrocyte, was investigated in the temporal neocortex of postmortem brain samples of 8 cases, either not demented or affected by senile dementia of the Alzheimer type. A negative correlation between the GS protein level and the density of both classical beta A4 deposits and senile plaques was evidenced. Such a correlation for GS underlies a dysfunction of the astroglial metabolism and particularly of the glutamate and ammonia neutralization. Since GS is sensitive to oxidative lesioning, the changes in GS level that were observed, occurring at the posttranslational stage, might reflect oxidative damage and have severe consequences on the pathological cascade of events.

Aged↗
PubMed1995

Does tumor control decrease by prolonging overall treatment time or interrupting treatment in laryngeal cancer?

PURPOSE: To evaluate treatment results of radiotherapy in laryngeal cancer and to retrospectively investigate the influence of treatment interruptions on local control rates. A multivariate analysis was performed to investigate the role of overall treatment time on local control rates. MATERIAL AND METHODS: From 1962 to end 1986, 864 patients with cancer of the larynx were treated with primary radiotherapy, with a variation of doses and treatment times. In 352 patients a systematic interruption of 2 weeks was done after 50 Gy (split-course). Local control rates were calculated by the actuarial method. A multivariate analysis was subsequently performed in order to identify independent variables influencing local control rates. RESULTS: The univariate analysis showed that in patients treated with a split-course schedule, local control rates were significantly lower in glottic cancer (p < 0.001), with differences of 7% in T1 (p = 0.05) and 11% in T2 (p = 0.11). In node-negative supraglottic cancer a difference of 10% (p = 0.16) was observed. The multivariate analysis showed the following factors to significantly influence local control: site, total dose, total treatment time, T and N stage. Split-course treatment was not an independently significant factor, probably caused by time being a stronger factor. In subgroup analysis, the effect of total treatment time remained statistically significant in T2 glottic cancer. CONCLUSION: A significant negative influence of treatment interruption was seen in glottic cancer, and a trend toward significance in node-negative supraglottic cancer in univariate analysis. A multivariate analysis showed a negative influence of prolonging treatment time in the total patient group. The effect remained significant in T2 glottic cancer in subsequent subgroup analysis, possibly due to the fact that there is little variation in tumour volume in this group. In larger tumours, where there is substantial variation in tumour volume and a higher probability of heterogeneity in radiosensitivity, the effect of dose-time variations could be more difficult to discern.

Female↗
PubMed1995

Angiosarcoma of the larynx.

The morphological and immunohistochemical features of a laryngeal angiosarcoma are described. Initially, the tumour was interpreted as a poorly differentiated squamous cell carcinoma. The laryngectomy specimen contained an extensive and haemorrhagic tumour consisting of irregular and dissecting vascular spaces delineated by pleomorphic endothelial cells. In addition to these obvious angiosarcomatous areas, islands of more compact growing tumour cells were present, reminiscent of a poorly differentiated squamous cell carcinoma. On immunohistochemistry, the tumour cells expressed factor VIII, Ulex europaeus I lectin, CD31 and vimentin. There was no expression of cytokeratin or epithelial membrane antigen. Angiosarcoma of the larynx is very rare and should be differentiated from a pseudo-angiosarcomatous carcinoma.

Antigens, Differentiation, Myelomonocytic↗
PubMed1995

Management of acute laryngeal trauma.

Accurate assessment of the extent of an acute laryngotracheal injury has permitted treatment ranging from observation to open reduction. The keystones for successful treatment of acute laryngeal trauma and hence for prevention of laryngeal stenosis are: Accurate evaluation of the larynx using laryngoscopy and CT scanning. Immediate airway management to provide a safe airway. Repair of displaced laryngeal fractures and mucosal lacerations with the placement of a soft silicone stent in the severe cases.

Fractures, Cartilage↗
PubMed1995

Experimental tracheal revascularization and transplantation.

Vascularized tracheal allografts would expand the domain of tracheal reconstructive surgery. The functional capability of vascularized tracheal allografts is closely correlated with immunologic parameters contributing to graft survival, about which little information is currently available. An orthotopic transplant model was developed that allows assessment of allograft function by examining healing at the graft-host junction and graft integrity during normal respiration.

Animals↗
PubMed1994

Acoustic analysis of tracheo-oesophageal versus oesophageal speech.

In order to evaluate the vocal quality of tracheo-oesophageal and oesophageal speech, several objective acoustic parameters were measured in the acoustic waveform (fundamental frequency, waveform perturbation) and in the frequency spectrum (harmonic prominence, spectral slope). Twelve patients using tracheo-oesophageal speech (with the Provox valve) and 12 patients using oesophageal speech for at least two months, participated. The main results were that tracheo-oesophageal voices more often showed a detectable fundamental frequency, and that this fundamental frequency was fairly stable; there was also a tendency to more clearly defined harmonics in tracheo-oesophageal speech. This suggests a more regular vibratory pattern in the pharyngo-oesophageal segment, due to the more efficient respiratory drive in tracheo-oesophageal speech. So, a better quality of the voice can be expected, in addition to the longer phonation time and higher maximal intensity.

Evaluation Studies as Topic↗