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Biomedical subjects

W Pirsig

Publications and source records attributed to W Pirsig.

At least 73 records · Page 4Linked to original sources
PubMed1992

Defective stimulation of proliferation and collagen biosynthesis of human bone cells by serum from diabetic patients.

We studied the influence of fasting serum from nine insulin-dependent diabetic children and adolescents under insufficient metabolic control on normal human bone cells in vitro compared with serum from eight sex- and age-matched controls. Cell number 24 h after plating was significantly less under diabetic serum, indicating impaired cell attachment, spreading and initiation of cell proliferation. Cell number after five days was reduced by 1% diabetic serum, while higher serum concentrations had diverging effects on osteoblast proliferation. Collagen synthesis of human osteoblasts was significantly reduced by 8% diabetic serum compared to 8% control serum, while synthesis of non-collagenous proteins was not affected. Duration of diabetes (several weeks up to 12 years) had no influence on these parameters. The serum from one patient, which was studied a second time under excellent metabolic control three months later, however, had lost its inhibitory influence on collagen synthesis of osteoblasts. The pattern of the interstitial collagen types I, III and V was not altered by diabetic serum. These results indicate that defective regulation of proliferation and collagen synthesis of osteoblasts by components present in human diabetic serum may be an important factor in the development of diabetic osteopenia. The negative influence might be explained in part by reduced levels of IGF-I and elevated levels of IGF binding protein-1 in the diabetic sera.

Adolescent↗
PubMed1991

Turbinate hypertrophy in habitual snorers and patients with obstructive sleep apnea: findings of acoustic rhinometry.

Forty-five habitual snorers (mean respiratory disturbance index = 6) and 22 patients with obstructive sleep apnea syndrome (mean respiratory disturbance index = 36) were examined by polysomnography, radiocephalometry, rhinomanometry, nasopharyngeal videoendoscopy, and acoustic rhinometry. In 97% of these patients, hypertrophy of the inferior nasal turbinates was found by acoustic rhinometry, while increased nasal resistance of various degrees was measured in 93% of all patients by active anterior rhinomanometry. Acoustic rhinometry demonstrated that the most resistive segment was located in the anterior parts of the nasal cavity and was built up by two compartments: the region of the isthmus nasi and the region of the head of the inferior turbinate. In our snoring patients, the cross-sectional areas at the head of the inferior turbinate were always smaller than the cross-sectional areas in the isthmus nasi, which in normal controls presented the minimal cross-sectional values of the whole nasal cavity. While rhino-manometry can only measure the amount of nasal resistance, acoustic rhinometry can clearly determine the exact size and location of the different stenoses in the nasal cavity that contribute to the increased nasal resistance.

Acoustics↗
PubMed1991

[Surgical therapy of obstructive sleep apnea syndromes: results of the Ulm treatment program].

The article reports on the results obtained by uvulopalatopharyngoplastic surgery (= UPPPS) in 31 patients suffering from obstructive sleep apnoea syndrome (= OSAS) and in 9 patients with habitual or obstructive snoring. All patients were subjected to thorough preoperative examination including rhinometry, nasopharyngeal video-endoscopy, radiocephalometry and polysomnography. In 8 out of 9 (89%) of the habitually snoring patients and in 17 of 31 (55%) of OSAS patients, surgery was successful. In these patients, a postoperative respiratory disturbance index (RDI) of less than 10 was recorded, whereas in 4 patients (13%) the postoperative RDI was between 10 and 15. Ten patients did not respond satisfactorily to UPPPS (32%). RDI was postoperatively still above 15. Analysis of patient data shows that almost all habitually snoring patients and the OSAS patients with slight overweight and low to medium apnoea index were successfully treated with UPPPS. In accordance with these results a treatment concept has been drawn up for OSAS patients that takes stock of all the possibilities and limitations of available conservative and surgical treatment methods.

Body Weight↗
PubMed1990

Digital signal analysis of snoring sounds in children.

Snoring sounds of 5 children with sleep-dependent compromised breathing were recorded. Underlying diseases were large adenoids, adeno-tonsillar hyperplasia, hemangioma of the tongue-base and Rubinstein-Taybi's syndrome associated with micrognathia. For comparison snoring sounds of a 42-year-old chronic snorer were analyzed. Time series of the power spectral density of the breath sounds were calculated as well as the mean power spectra of the recordings. The results show that the frequency spectrum reflects the pathomechanism responsible for the production of the abnormal breath sound. In adults, simple snoring is due in large part to vibrations of the soft palate. This can be identified in the frequency spectrum as a low-frequency component with a large number of harmonics. In children with enlarged adenoids and tonsils the soft palate is impeded in its movement which can be demonstrated in the frequency spectrum as a lack of low-frequency components and harmonics. Craniofacial anomalies are characterized by special spectral patterns.

Adenoids↗
PubMed1990

[How can hyperreflexia rhinopathy be modified surgically? I. Literature review].

A review of the literature on the surgery of vasomotor rhinitis revealed only a few studies with information by which to judge the value of a special surgical method, especially concerning its long-term results. The following modalities of treatment were reviewed: submucous resection of the septum (Killian), Vidian neurectomy, conchal surgery (diathermy, partial and total turbinectomy, cryosurgery, laser-surgery). As far as information is available, advantages and shortcomings of individual methods are listed in tables. Partial turbinectomy seems to be most effective in reducing nasal obstruction without damaging nasal functions. Nasal hypersecretion is not sufficiently influenced by the cited surgical methods. In the authors' hospital, conchal surgery is performed in about sixty percent of all nasal operations. Gray's method of anterior turbinoplasty of the inferior turbinate is used.

Cryosurgery↗
PubMed1990

[How can hyperreactive rhinopathy be modified surgically? II: Acoustic rhinometry and anterior turbinoplasty].

By means of the acoustic reflection technique, or acoustic rhinometry, all cross-sectional areas of the upper airway can be measured by an acoustic signal. In this paper, the normal mean curve of 134 normal probands is determined. This normal curve shows the minimum cross-sectional area (I-notch) to be located at the Isthmus nasi. The second narrowest segment of the nasal cavity is located at the head of the inferior concha (C-notch). In patients with turbinate hypertrophy due to allergic or vasomotor rhinitis the minimum cross-sectional area is sited at the head of the inferior turbinate. Furthermore, acoustic rhinometry allows the exact size and location of the congested mucosa to be determined following provocation with allergens in patients with allergic rhinitis. Acoustic rhinometry could further demonstrate why nasal breathing in patients with turbinate hypertrophy improves in the long term after anterior turbinoplasty: in this operation the narrow cross-sectional areas at the head of the inferior turbinate are enlarged. Acoustic rhinometry not only allows the location and size of the various deviations of the nasal structures to be distinguished from normal (valve stenosis, septal deviation, turbinate hypertrophy, tumor masses), but also allows an exact demonstration of the efficacy of rhinosurgical techniques.

Adult↗
PubMed1990

History of rhinology: nasal specula around the turn of the 19th-20th century.

This review is an excursion into the past to find the prototypes of the various nasal specula around the beginning of our century. The oldest prototype is documented in the ancient Hindu text Sushruta-samhita (6th century BC): a tubular nasal speculum. The bivalved forceps-like nasal speculum was mentioned by Hippocrates and can be followed with and without self-retaining mechanisms to the modifications of Killian and of Cottle. U- or Y-shaped springlike devices to open the nares have been known since the publication of Arnold de Villanova from the 13th century. They were reintroduced in a modification by Thudichum in 1868. Fraenkel's speculum (1872) combines fenestrated blades with a screw-set for self-retaining. Duply (1868) modified the split and funnel-shaped ear speculum of Bonnafont, the branches of which can be varied by a screw. In addition to this description of the prototypes of specula a short development of the facilities to illuminate the inner nose is given starting with the sun light and ending with the glass fiberoptic.

Europe↗
PubMed1990

Diagnostic value of acoustic rhinometry: patients with allergic and vasomotor rhinitis compared with normal controls.

By means of the acoustic reflection technique, termed acoustic rhinometry, cross-sectional areas along the whole upper airway can be measured by an acoustic click. This paper describes the normal values obtained from 134 probands. The normal curve shows the minimal cross-sectional area (I-notch) to be located at the isthmus nasi. The second narrowest segment of the nasal cavity is located at the head of the inferior concha (C-notch). In patients with turbinate hypertrophy due to allergic or vasomotor rhinitis the minimal cross-sectional area is sited at the head of the inferior turbinate. Furthermore, acoustic rhinometry allows exact measurements of size and location of the congested mucosa following challenge with allergens in patients affected with allergic rhinitis. After anterior turbinoplasty of patients with turbinate hypertrophy improved nasal breathing was associated with an enlargement of the cross-sectional areas at the head of the anterior inferior turbinate. Acoustic rhinometry not only enables to distinguish the various deviations of the nasal structures from normal (valve stenosis, septal deviation, turbinate hypertrophy, tumour masses) concerning their location and size, but also allows to demonstrate exactly the efficacy of rhinosurgical techniques.

Adult↗
PubMed1989

[Radiocephalometric findings and duration of snoring in habitual snoring and obstructive apnea syndrome].

In 11 patients with chronic snoring and 12 subjects with obstructive apnoea syndrome the percentage of snoring duration above a preset sound pressure level during one night's sleep was correlated with the radiocephalometric data. Cephalometric distances PAS, PM-Pg, MP-H and angles SNA and SNB representing measures for posterior airway space, size of soft palate, relative position of hyoid bone and relative position of maxilla and mandibula were evaluated. Each patient showed pathological deviations from normal values in at least one of the cephalometric parameters. A significant correlation between snoring duration and a single cephalometric distance could not be found. However, an index combining pathological deviations from all three cephalometric distances showed a highly significant correlation with snoring duration (p less than 0.01 - Fig. 11), as did deviations from normal values of angle SNB (p less than 0.03 - Fig. 10). Our findings indicate that snoring and obstructive apnoea syndrome are not only caused by neurologic dysregulation, and that in addition specific craniofacial anomalies are prerequisites for the development of the disease. For the first time it is demonstrated that these anomalies exist in chronic snorers as well as in apnoeic patients. Our findings support Lugaresi's hypothesis that heavy snoring and obstructive apnoea syndrome are based on the same defect and differ in severity only.

Adult↗
PubMed1989

[What is new in nasopharyngeal video fiber optic endoscopy in the diagnosis of snoring and patients with obstructive apnea?].

Videoendoscopy of the oropharynx was performed in 57 patients with habitual snoring and obstructive sleep apnoea syndrome. Endoscopy was done in waking supine subjects relaxed and during voluntary snoring, Esmarch's and modified Müller's manoeuvre. Evaluation of results for the first time was semiquantitative. Statistical analysis showed significant correlations (p less than 0.004) between movements of the base of the tongue and the modified Müller's manoeuvre. For the first time it could be shown that the dynamic changes in the pharyngeal walls during voluntary snoring are identical with those in the modified Müller's manoeuvre (p less than 0.006). Frame-by-frame analysis demonstrated epiglottic movements in the inspiratory cycle of snoring which result in a massive occlusion of the airway in 65% of our patients. Videoendoscopy is able to provide valuable information on anatomical details and potential obstructive sites but cannot predict the success of surgical interventions like UPPP. Videoendoscopy due to its high resolution in the time domain can demonstrate pathophysiological events which are otherwise inaccessible. For the experienced examiner videoendoscopy is a fast tool for obtaining live information on the surgical site.

Airway Obstruction↗
PubMed1989

[Uvulopalatopharyngoplasty without complications: a Fujita complication].

In 17 illustrations, a modification of Fujita's technique of UPPP is presented. This operation consists of excising redundant velar tissues from the free margin of the soft palate, tonsillar pillars, and uvula without reducing the muscles of the velum. In addition, the uvula muscle is almost completely preserved. Seventy patients, with habitual snoring or with obstructive sleep apnea syndrome, who underwent this surgery were followed-up from six to 24 months and did not show any palatal insufficiency with air and liquid escape through the nose. Additional remarks are made concerning the difficulties encountered during intubation of 60 percent of patients with chronic rhonchopathy.

Follow-Up Studies↗
PubMed1989

Human nasal septal cartilage: analysis of intracellular enzyme activities, glycogen content, cell density and clonal proliferation of septal chondrocytes of healthy adults and acromegalic patients.

The human septal cartilage is of ectodermal origin and contributes to midfacial growth and development. Acromegaly is an endocrine disease due to growth hormone (Gh) excess originating from a somatotrophic adenoma of the pituitary gland. Excessive Gh levels lead to high insulin-like growth factor I (IGF I) concentrations, which are known to stimulate cartilage growth in vivo and in vitro. One of the salient clinical pictures is coarsening of the midface and enlargement of the septal cartilage. Septal cartilage was obtained from 8 acromegalic patients during transnasal hypophysectomy and from 10 healthy adults during septoplasty to analyse the following aspects of cartilage biochemistry, metabolism and growth. 1. Intracellular glycogen, the major source of energy of chondrocytes, was determined enzymatically and found to be drastically reduced in acromegaly. 2. Several intracellular enzymes, related to biomatrix degradation, showed a strict local pattern of distribution. Cathepsin B activity, a neutral proteinase degrading both the helical and nonhelical region of the collagen molecule was significantly increased in acromegaly, whereas alkaline phosphatase activity, an enzyme related to mineralization of the cartilage at the chondroosseous junction was depressed in acromegaly. 3. The cell density in some areas of the septal cartilage was increased in acromegaly, whereas the clonal proliferation rate of its chondrocytes in response to serum and growth factors was decreased. Chondrocytes both of healthy adults and acromegalic patients could be effectively stimulated by insulin-like growth factor I and II and to a lesser extent by epidermal growth factor.

Acromegaly↗
PubMed1989

[Aplasia and hypoplasia of the side of the nose in the Mocha Period and today].

In earthenware vessels from the Moche period (200-700 A.D.) pathological findings of nasal deformities have been depicted in a realistic manner. By means of two recent casuistics and of two portrait vessels of Old Peru it is demonstrated how exactly the nasal pathology was observed by the artists of the Moche period. The first example shows a unilateral hypoplasia of the nasal ala due to injury in early childhood, the second example shows a bilateral aplasia of the nasal alae due to an intrauterine growth disturbance.

Adolescent↗