Search PubMed⌕ Search

Biomedical subjects

G H Wiest

Publications and source records attributed to G H Wiest.

34 records · Page 2Linked to original sources
PubMed2000

[Retroperitoneal desmoid tumor with kidney failure in familial adenomatous polyposis].

HISTORY AND FINDINGS: A 39-year-old man was hospitalized because of continually rising urinary creatinine and blood urea nitrogen concentration. He was known to have familial adenomatous polyposis (FAP), first diagnosed 18 years previously and re-Physical examination was unremarkable except for pain on percussion over both kidney regions. There was a well-healed laparotomy scar. INVESTIGATIONS: Ultrasound revealed chronic bilateral obstructive renal disease, grade II-III, and computed tomography showed a conglomerate retroperitoneal tumour with obstruction of both ureters at the level of the lower pelvis. This tumour had first been noted first 3 years after the colectomy when the patient complained of abdominal pain. It had been identified histologically as a nonresectable retroperitoneal desmoid tumour. TREATMENT AND COURSE: An external fistula was made, relieving the renal retention. To suppress growth of the desmoid tumour Sulindac, a nonsteroid anti-inflammatory drug, was administered. Genetic molecular analysis revealed a germ line defect in codon 1690 of the APC gene. It is intended to examine other members of the family for the presence of this defect. CONCLUSION: Desmoid tumours are more common in persons with FAP and are among the most frequent extracolic causes of their death. Treatment options are critically analysed.

Adenomatous Polyposis Coli↗
PubMed2000

In vivo efficacy of heated and non-heated humidifiers during nasal continuous positive airway pressure (nCPAP)-therapy for obstructive sleep apnoea.

Upper airway dryness is a frequent side-effect of nasal continuous positive airway pressure therapy (nCPAP) in obstructive sleep apnoea (OSA). In this situation, heated or non-heated passover humidifiers are often added to the nCPAP-therapy. The efficacy of these two modes in terms of increasing the absolute humidity of the inspired air in vivo has so far not been established. The present investigation was therefore designed to compare various heated and non-heated passover humidifiers in terms of the their ability to increase the absolute humidity in the inspired air during nCPAP. In six healthy test individuals, nCPAP-therapy at pressures of 5 mbar and 10 mbar was simulated, and the relative humidity and temperature of the air within the tube at the junction between CPAP tube and mask were measured. In each test person, measurements were carried out both with and without the two heated (HC 100, Fischer&Paykel Inc., New Zealand and HumidAire, ResMed Ltd., Australia) and two non-heated (Oasis and Humidifier, both from Respironics Inc., U.S.A.) passover humidifiers under steady-state conditions. The absolute humidity was calculated from the relative humidity and temperature measurements. The mean (SD) absolute humidity (gm(-3)) in the steady-state was significantly (P<0.05 higher with each of the humidifiers than that calculated when no humidifier was used. The relevant figures were as follows: no humidifier: 10(-2) (1.8) gm(-3) (at 5 mbar)/9.8 (1.8) gm(-3) (at 10 mbar); Humidifier: 16.4 (0.97)/15.6 (1.26); Oasis: 17.3 (0.97)/ 16.7 (0.93); HC100: 26.5 (1.40)/26.2 (1.23); HumidAire: 31.8 (2.50)/30.9 (2.64). The mean increase in absolute humidity (in gm(-3)) with the aid of the heated humidifiers was 16.3 (5 mbar) gm(-3)/16.4 (10 mbar) gm(-3) with HC100 and 21.6/21.1 with HumidAire, and in both cases was clearly and significantly (P=0.028) higher in comparison with the non-heated humidifiers--6.2/5.8 with Humidifier and 7.2/6.9 with Oasis. In terms of the absolute humidity achieved within the CPAP tube system, the heated humidifiers were clearly superior to the non-heated humidifiers. These results were, however, obtained under laboratory conditions, and therefore cannot be translated unreservedly to the situation represented by long-term CPAP-treatment. Furthermore, it is possible that the smaller humidification capacity of the non-heated humidifiers may still suffice to meet the requirements of clinical use in terms of effectively preventing dry airways under CPAP treatment. This point, however, needs further investigation on the basis of long-term clinical studies.

Adult↗
PubMed2000

[Ileocecal manifestation of Schoenlein-Henoch purpura as a rare differential Crohn disease diagnosis].

In the case of a 21-year-old patient gastroscopy and coloscopy were performed because of recurrent abdominal pain with diarrhea and vomiting. Colonoscopy showed moderate signs of inflammation of the rectum and aphthoid ulcerations in the terminal ileum. Since the macroscopic and clinical presentation was compatible with Crohn's disease, therapy with sulfasalacine was started. Because histology showed only lymphoid hyperplasia and the patient was asymptomatic at that time, the medication was ceased. Recurrence of abdominal pain and weight loss, proteinuria and a recurrent palpable purpura of the shanks in synopsis with the result of the previous colonoscopy led to a suspected diagnosis of Schoenlein-Henoch purpura with cutaneous, renal and abdominal manifestation which was confirmed by dermal and renal biopsies.

Adult↗
PubMed2000

An auto-continuous positive airway pressure device controlled exclusively by the forced oscillation technique.

The forced oscillation technique (FOT) has been demonstrated to be a very sensitive tool for the assessment of upper airway obstruction during nasal continuous positive airway pressure (CPAP) therapy for obstructive sleep apnoea (OSA). The present study was designed to evaluate the therapeutic efficacy of a novel auto-CPAP device based exclusively on the FOT. Following manual CPAP titration, 18 patients with OSA (mean apnoea/hypopnoea index (AHI) 48.0+/-28.1) were allocated to conventional CPAP and auto-CPAP treatment under polysomnographic control in randomized order. The patients were asked to assess their subjective daytime sleepiness using the Epworth Sleepiness Scale (ESS). The mean AHI during auto-CPAP treatment was 3.4+/-3.4 and was comparable with that obtained during conventional CPAP treatment (4.2+/-3.6). The analysis of sleep architecture, the arousal index (6.6+/-2.1 versus 7.3+/-4.4) or the ESS (5.6+/-1.8 versus 7.3+/-4.4) did not reveal any significant differences. However, the mean CPAP pressure during auto-CPAP treatment (0.84+/-0.26 kPa) and in particular the pressure applied in the lateral body position (0.74+/-0.35 kPa), was significantly lower than that employed in conventional CPAP treatment (0.93+/-0.16 kPa, both comparisons: p<0.05). The auto-continuous positive airway pressure device proved equally as effective as conventional continuous positive airway pressure. However, the mean treatment pressure was significantly reduced, especially when patients were sleeping in the lateral position.

Adult↗
PubMed1999

Are snoring medical students at risk of failing their exams?

STUDY OBJECTIVES: To compare the examination results of self-reported snoring and nonsnoring medical students DESIGN: We studied the examination scores obtained by medical students answering a multiple-choice test forming part of their final examinations. The students were asked to classify themselves as "nonsnorers," "occasional snorers," or "frequent snorers," and to state their age, sex, height and weight. SETTING: University Hospital, Erlangen, Germany PARTICIPANTS: 201 medical students (61% males/39% females; mean age 24.6 +/- 2.1 years; BMI 22.4 +/- 2.5 kg/m2) taking their final examinations in internal medicine. MEASUREMENTS AND RESULTS: Seventy-eight students (38.8%) claimed to be nonsnorers, 99 (49.3%) occasional snorers and 24 (11.9%) frequent snorers. The mean examination scores (adjusted for age, sex, and BMI) were 69.6 +/- 9.9% for the nonsnorers, 65.3 +/- 10.0% for the occasional snorers and 62.0 +/- 8.2% for the frequent snorers (p < 0.0001). 12.8% of the nonsnorers failed the exam, compared with 22.2% of the occasional snorers and 41.7% of the frequent snorers (p < 0.001). Logistic regression analysis showed an association between failing the exam and snoring (p = 0.013), but not between failure and age, BMI, or sex (relative risk for snorers adjusted for age, sex and BMI: 1.26; 95%--CI 1.01-1.57). CONCLUSIONS: In medical students, snoring seems to be associated with an increased risk of failing exams in a dose-response manner, even after controlling for age, sex and BMI. For the present, the mechanisms underlying this association must remain a matter of speculation. Snoring-related sleep fragmentation ("upper airway resistance syndrome") might be a causal factor.

Achievement↗
PubMed1999

A heated humidifier reduces upper airway dryness during continuous positive airway pressure therapy.

Upper airway dryness is a frequent side-effect of nasal continuous positive airway pressure (nCPAP) therapy in obstructive sleep apnoea (OSA). In this situation, heated humidification is often used. Alternatively, oily nose drops are frequently applied to relieve dryness. The present study aimed to investigate the efficacy of a heated humidifier in comparison with oily nose drops. Twenty-four OSA patients complaining of serious nCPAP-related upper airway dryness were randomized to 6 weeks of treatment either with heated humidification (HC 100, Fischer & Paykel, Inc., Auckland, New Zealand) or oily nose drops (Colda-Stop, Desitin, Inc., Germany). The patients completed questionnaires on the degree and frequency of upper airway dryness, compliance with nCPAP, intention to terminate nCPAP and comfort during the nCPAP therapy. All 12 patients treated with heated humidification improved in terms of the degree and frequency of upper airway dryness, and reported greater comfort when using the nCPAP device. All patients in the heated humidification group intending to terminate nCPAP therapy because of upper airway dryness persisted with nCPAP on addition of humidification. In contrast, only five out of 12 patients (42%) in the oily nose drops group reported their degree of upper airway dryness to be improved (P = 0.003), only three patients (25%) reported an improvement in the frequency of upper airway dryness (P < 0.001), and only five patients (42%) reported greater comfort when using the nCPAP device with oily nose drops (P < 0.001). In the group using oily nose drops none of the three patients who intended to terminate nCPAP therapy persisted with nCPAP. Heated humidification is highly effective and superior to oily nose drops in reducing the symptoms of upper airway dryness during nCPAP.

Aged↗
PubMed1998

[Secondary obstructive sleep apnea syndrome in a patient with tracheal stenosis and bilateral recurrent paresis. Successful treatment with nasal continuous positive airway pressure therapy].

HISTORY AND ADMISSION FINDINGS: A 67-year-old woman complained of marked daytime sleepiness, as well as loud snoring and apnoeas during sleep. She was known to have had 3 thyroidectomies for goitre 41, 23 and 12 years ago, with known tracheal stenosis and recurrent nerve palsy for 11 years. Physical examination revealed marked stridor, hoarse voice and slightly enlarged and palpable recurrent right thyroid. INVESTIGATIONS: Polysomnography demonstrated a clearly elevated obstructive sleep apnoea activity (apnoea index: 34/h, apnoea-hypopnea index: 40/h, desaturation index: 31/h, minimal saturation: 63%). Selective tracheal imaging showed subglottic tracheal stenosis with an inspiratory luminal diameter of 4 mm and an expiratory luminal diameter of 8 mm. Lung function analysis revealed marked flattening of the flow-volume curve as sign of a functionally effective tracheal stenosis. These findings indicated a secondary obstructive sleep apnoea (OSA) due to tracheal stenosis and bilateral recurrent nerve palsy. The patient declined further studies, such as bronchoscopy. TREATMENT AND COURSE: As the patient did not want any surgical treatment, nasal continuous positive airway pressure therapy (CPAP) was instituted as a trial. No apnoea occurred at a pressure of 12 mm H2O and this was well tolerated. She has now continued CPAP at home for 12 months and her vigilance was markedly improved. CONCLUSIONS: Tracheal stenosis or recurrent nerve palsy is a rare cause of OSA which can be effectively treated by nasal CPAP.

Aged↗
PubMed1998

Evaluation of an auto-CPAP device for treatment of obstructive sleep apnoea.

BACKGROUND: Auto-CPAP machines used in the treatment of obstructive sleep apnoea (OSA) are designed to vary the treatment pressure automatically in order always to apply the actually needed pressure. Consequently they should be able to achieve at least identical therapeutic effects as conventional constant pressure CPAP with a lower mean treatment pressure. The present study was designed to evaluate the therapeutic efficacy and the treatment pressure of an auto-CPAP machine (REM + auto, SEFAM) in comparison with a conventional CPAP device. METHODS: Following CPAP titration, 16 patients with OSA were allocated to receive conventional CPAP and auto-CPAP treatment under polysomnographic control in a randomised order. After each treatment the patients were asked to assess the therapy using a questionnaire; a vigilance test was also carried out and subjective daytime sleepiness was evaluated using the Epworth Sleepiness Scale (ESS). RESULTS: The mean (SD) apnoea/hypopnoea index (AHI) during auto-CPAP treatment was comparable with that during conventional CPAP treatment (4.2 (5.1) versus 3.6 (4.0)). Neither an analysis of sleep architecture nor the arousal index (7.4 (4.1) versus 7.0 (4.3)) revealed any significant differences. Daytime sleepiness measured with the ESS was also comparable (5.3 (3.4) versus 6.5 (4.2)). The vigilance test showed normal values after both treatments in all patients with no significant differences. The mean pressure during auto-CPAP treatment (8.1 (2.9) mbar), however, was significantly higher than that employed in conventional CPAP treatment (7.6 (2.7) mbar; mean difference 0.5 mbar; 95% CI 0.1 to 0.9 mbar; p < 0.05). CONCLUSIONS: Auto-CPAP was equally as effective as conventional CPAP with respect to therapeutic efficacy. The aim of reducing the treatment pressure with auto-CPAP, however, was not achieved.

Adult↗
PubMed1997

[Auto-CPAP treatment in obstructive sleep apnea syndrome: a prospective randomized study during initiation of treatment].

OBJECTIVE: The efficacy and acceptance of self-regulated continuous positive airway pressure (auto-CPAP) ventilation was compared with conventional CPAP administration in the treatment of patients with obstructive sleep apnoea. PATIENTS AND METHODS: Using a cross-over design, under polysomnographic monitoring in a sleep laboratory, 25 patients with obstructive sleep apnoea underwent conventional CPAP or auto-CPAP treatment. Using a questionnaire, patients gave their assessment of its acceptability and efficacy after each treatment session. RESULTS: The mean pressure during treatment was the same in the two groups (7.2 +/- 1.9 versus 7.1 +/- 1.9 mbar; no significant difference). Maximal pressure during auto-CPAP averaged 3.7 +/- 2.1 mbar higher than during conventional CPAP ventilation. The mean apnoea-hypopnoea index (AHI) during auto-CPAP, 4.4 +/- 4.3 mbar, during auto-CPAP was significantly higher than during conventional CPAP treatment (2.8 +/- 2.8 mbar; P = 0.044). In eight patients on auto-CPAP an AHI of 5 or less could not be reached, while an AHI of 5 or less was obtained in all but three patients under conventional CPAP. In a subgroup of 17 patients, in whom a reduction of AHI to at most 5 was achieved with both conventional and auto-CPAP, analysis of sleep pattern and of arousals was similar with the two forms of ventilation. Several patients reported that with auto-CPAP falling in sleep was more difficult and they slept less well. None of the patients preferred auto-CPAP. CONCLUSION: By means of the auto-CPAP neither a pressure reduction nor an improvement in compliance could be achieved. Therapeutic effectiveness was significantly less as with conventional CPAP therapy.

Adult↗
PubMedDate not supplied

Mismatch repair deficiency in sporadic synchronous colorectal cancer.

BACKGROUND: Hereditary non-polyposis colorectal cancer (HNPCC) patients frequently develop synchronous colorectal cancer (SCRC) which also occurs sporadically in other patients. Recent studies on microsatellite instability (MSI) in sporadic SCRC diverge completely in their findings (0%-100%). In the present study MSI and mismatch repair (MMR) proteins were evaluated according to standardised criteria (exclusion of a family history, MSI analysed according to NCI recommendations) METHODS: Paraffin embedded sections of SCRC of 30 patients were evaluated for MSI and the loss of protein expression of hMLH1 and hMSH2. RESULTS: 3 out of 30 (10%) patients exhibited MSI-H which 5 out of 30 (17%) showed MSI-L. Loss of protein expression of either hMLH1 or hMSH2 was found in all cases of MSI-H and none of the MSI-L cancers. CONCLUSION: MSI is found in sporadic cases of SCRC to about the same extent as it is mentioned in the literature on sporadic single colorectal cancers. Immunohistochemistry with mismatch repair proteins could be used as a pre-screening for MMR deficiency in sporadic SCRC.

Adaptor Proteins, Signal Transducing↗
PubMedDate not supplied

Ki-67 expression and residual tumour (R) classification are associated with disease-free survival in desmoid tumour patients.

BACKGROUND: In order to evaluate prognostic factors in the long-term survival of desmoid tumour patients, analysis of clinicopathological, immunohistochemical and follow-up data was performed. PATIENTS AND METHODS: Between 1969 and 1998, 54 patients underwent resection of aggressive fibromatosis (desmoid) and 33 of them (10 patients with FAP and 23 sporadic) were followed-up with a median time of 130 months (range 10-355 months). Additionally, immunohistochemical analysis of the desmoid tumours using Ki-67 was performed. RESULTS: In univariate analysis, curative resection (R0) (p<0.001) and low proliferation of Ki-67 (p=0.002) were of significant positive prognostic value concerning disease-free survivaL R0 and absence of Ki-67 staining were significantly associated with each other (p=0.004). CONCLUSION: Ki-67 seems to serve as a predictive marker concerning disease-free survival of desmoid tumour patients. In patients presenting with Ki-67 positive desmoids, which are unlikely to be resected in a curative manner, alternative treatment (e.g. sulindac) may be preferable.

Adenomatous Polyposis Coli↗