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Biomedical subjects

C Buchwald

Publications and source records attributed to C Buchwald.

At least 19 recordsLinked to original sources
PubMed2007

Effects of calcium on the erosive potential of acidic candies in saliva.

Theoretical calculations have shown that acidic candies may be potentially erosive upon consumption. However, little is known about the protective effect of adding calcium to potentially erosive candies and about the protective effects of saliva that cannot be fully accounted for by theoretical calculations. Therefore, the aims of this study were to (1) determine the erosive potential of acidic candies with and without calcium and (2) to determine differences between theoretically calculated erosive potential and actual erosive potential in saliva. Twenty healthy test persons sucked acidic candy with and without calcium while their whole saliva was collected into a closed system at different times: baseline, candy-stimulated, and post-stimulated. The erosive potential of the candy was evaluated from candy-induced changes in saliva degree of saturation with respect to hydroxyapatite (HAp) and directly by dissolution of HAp crystals in candy-stimulated saliva. The results showed that similar salivary stimulation was obtained with both candies. The modified candy released more than 13 mmol/l of calcium into saliva, resulting in a lower critical pH, and considerably lower erosive potential than the control (p < 0.001). Although a significant correlation was obtained between theoretical calculation of DS(HAp) and dissolution of HAp crystals (r(s) = 0.65; p < 0.001), many samples obtained by sucking modified candy showed no signs of HAp dissolution in spite of being undersaturated. We conclude that saturation levels and critical pH may not fully reflect when dental erosion is expected to occur in saliva and that calcium addition reduces the erosive potential of acidic candies.

Adult↗
PubMed2006

Immediate erosive potential of cola drinks and orange juices.

Little is known about the erosive potential of soft drinks within the first minutes of exposure to teeth, and about the potentially protective role of salivary proteins. We hypothesized that the erosive potential is determined primarily by pH and decreases in the presence of salivary proteins. To investigate this, we first added uncoated hydroxyapatite crystals and, second, salivary-protein-coated hydroxyapatite crystals to 20 commercially available cola drinks and orange juices simultaneously, with pH recordings every 15 sec for 3 min. The amount of apatite lost per liter of soft drink per sec was calculated from titratable acidity values to each pH obtained by crystal addition. The erosive potential within the first minutes of exposure was determined solely by the pH of the drink, and the erosive potential was ten-fold higher in cola drinks compared with juices. However, salivary proteins reduced the erosive potential of cola drinks by up to 50%.

Beverages↗
PubMed2006

Sinonasal schwannoma--a clinicopathological analysis of five rare cases.

Schwannoma of the nasal cavity or the sinuses is a rare condition. We report a small series of five consecutive patients; three males and two females, age range 22-81 years, all Caucasian. Symptoms were typically non-specific, and the tumours were often quite large when diagnosed, being locally infiltrating and even destructive. Histologically, the tumours were remarkable by sparse occurrence of Antoni type B areas and lack of encapsulation. Four cases were benign; however, one case of melanotic schwannoma, exhibited malignant transformation. Two of the patients had intracranial involvement, but with an intact dura. All tumours were treated surgically; only the malignant case received adjuvant radiotherapy. Patients were followed from five months to 15 years, with a median of 57 months. The benign cases have so far shown good prognosis without recurrences; however, in the case of the melanotic schwannoma a fatal malignant transformation was seen 13 years after initial diagnosis. On the basis of our review early detection and complete surgical removal is recommended.

Adult↗
PubMed2005

Effects of sucking acidic candies on saliva in unilaterally irradiated pharyngeal cancer patients.

Patients who have received radiation therapy on the head and neck area often use acidic candies to relieve symptoms of dry mouth. Therefore, the aim of this study was to determine the erosive potential in relation to teeth of an acidic candy in 10 such patients. The patients sucked the candy while their whole saliva was collected into a closed system at different times: baseline, candy-stimulated, and post-stimulated. The erosive potential of the candy was evaluated from candy-induced changes in saliva degree of saturation with respect to hydroxyapatite (HAp). Previously published normative values were used for comparison. The results showed that saliva became significantly more undersaturated with respect to HAp in irradiated patients, and failed to return to baseline values during the post-stimulatory period, which it normally does in healthy individuals. Thus, prevention of dental breakdown in these patients should involve counseling regarding choice of stimulant for dry mouth relief.

Acids↗
PubMed2001

[Treatment of recurrent epistaxis with endoscopic electrocoagulation of the sphenopalatine artery].

INTRODUCTION: Treatment of posterior epistaxis with an intranasal balloon catheter (double balloon--Epistat) or posterior balloon (Foley catheter) as a posterior packing combined with a gauze plug as the anterior packing is often very troublesome for the patient. In the western world, the introduction of endoscopic electrocoagulation or ligation of the sphenopalatine artery has proved to be effective in the treatment of persistent posterior epistaxis, and it reduces morbidity. We have therefore introduced the same treatment modality. MATERIAL AND METHODS: We have used this technique so far on six patients with persistent posterior epistaxis. They were admitted to the ENT Department, H:S Rigshospitalet, Copenhagen, during the period 1.4.2000-15.11.2000. RESULTS: The treatment terminated the epistaxis in all cases. One patient had anterior epistaxis postoperatively, and this was treated with ligation of the arterior ethmoidal artery. The time spent in hospital after the operation was 1-2 days. CONCLUSION: This method is recommended for the treatment of persistent posterior epistaxis, when functional endoscopic techniques are mastered. Early treatment reduces morbidity and cuts down the stay in hospital.

Adult↗
PubMed2001

Human papilloma virus and p53 expression in carcinomas associated with sinonasal papillomas: a Danish Epidemiological study 1980-1998.

OBJECTIVES: To determine a putative role and relation between human papilloma virus (HPV) and p53 in the etiology of sinonasal carcinomas associated with papillomas. STUDY DESIGN: The study group consists of all patients with sinonasal carcinomas associated with papillomas diagnosed in Denmark from 1980 to 1998. After reviewing our national pathological files, tumor tissues from 36 patients were collected, comprising 15% of the total cases of sinonasal carcinomas. In 35 cases a squamous cell carcinoma was demonstrated and in one case an adenocarcinoma was evident. Inverted papilloma was associated with carcinoma in 31 cases and exophytic papillomas in 5 cases. The material was investigated for HPV using polymerase chain reaction analyses with two sets of consensus primers (GP5+/GP6+ and MY09/MY11). The HPV-positive cases were submitted to dot-blot hybridization to establish the HPV type. Using immunohistochemistry, the p53 expression was determined. A p53 overexpression is defined as positive staining in 10% or more of the tumor cells. RESULTS: Among 30 examined cases of carcinomas associated with inverted papillomas, 4 cases were HPV-positive (13%). P53 overexpression was not shown among the HPV-positive cases, whereas p53 overexpression was seen in 21 of the 24 (88%) examined HPV-negative cases. Among the 5 carcinomas associated with exophytic papillomas, HPV was demonstrated together with p53 overexpression in 3 cases (60%). In addition, one case more was with p53 overexpression. CONCLUSION: An inverse relation between HPV and p53 overexpression in sinonasal carcinomas associated with inverted papillomas appears to have been demonstrated. HPV and p53 might also have an etiological role among the carcinomas associated with exophytic papillomas.

Adenocarcinoma↗
PubMed2001

An extensive maxillary pneumosinus dilatans.

Pneumosinus dilatans is a very rare lesion. An aggressive case of a maxillary pneumosinus dilatans is presented. CT and MRI showed that the lesion involved the orbit, cheek and nasal cavity. A reopening to the affected maxillary sinus as a FESS procedure was performed with success.

Adult↗
PubMed2000

Database developed to record and evaluate computer aided endonasal surgery results.

Computer aided surgery has been used in the Department of Otolaryngology--Head & Neck Surgery, Rigshospitalet, Copenhagen since October 1998, and is now a regular supplement to conventional functional endonasal sinus surgery (FESS) and management of anterior skull base lesions. This technique was designed to enhance surgical precision and thoroughness and to reduce complications. Since this is a new technique, the clinical findings and surgical outcome are prospectively collected in a database. Results for conventional FESS are entered in the same database for comparison. The aim of this study is to present a standardized Danish database.

Databases as Topic↗
PubMed1998

Expression of p53 in normal nasal mucosa and in sinonasal papillomas with and without associated carcinoma and the relation to human papillomavirus (HPV).

The aim of the present study was to investigate the expression of p53 in sinonasal papillomas, carcinomas ex papillomas and normal nasal mucosa. Furthermore, we wanted to study the expression of p53 in relation to the presence of human papilloma virus (HPV). Immunohistochemical staining was performed on 37 formalin-fixed paraffin-embedded biopsies comprising seven biopsies from normal nasal mucosa, 13 papillomas of an exophytic growth pattern, 12 papillomas of an endophytic growth pattern and five carcinomas. The level of p53 overexpression was defined as more than 5% positive nuclei. The normal nasal mucosa showed no positive nuclei. The papillomas of both exophytic and endophytic growth patterns showed scattered positive nuclei, but in all cases this was less than 5%. p53 was overexpressed in three out of five carcinomas. In conclusion, we found an overexpression of p53 in carcinomas occurring in sinonasal papillomas but not in the benign tumours of the sinonasal mucosa. Thus, this report supports the concept that p53 may have a role in the carcinogenic process in head and neck tumours.

Biopsy↗
PubMed1998

An aggressive and invasive growth of juvenile papillomas involving the total respiratory tract.

A malignant course of juvenile laryngeal papillomatosis has rarely been reported. In the present case the patient had had laryngeal papillomas since the age of three years. The papillomas gradually spread to the entire respiratory system, and during 30 years the patient was operated on more than 80 times. At present an invasive tumour spreading from the tongue into the parapharyngeal space, extending to the cranial base, has been demonstrated by magnetic resonance imaging (MRI). Intralesional therapy with Cidofovir, a promising antiviral drug against human papillomavirus (HPV) infection, was started with some clinical effect, although only on the superficial tumour growth. Histology of removed tumour tissue has demonstrated a mixture of exophytic and inverted growth pattern, and has mainly been interpreted as benign, in spite of a focally high mitotic index and an intermittent lack of maturation in the epithelium. In the most recent biopsies a verrucous carcinoma has been diagnosed. Expression of p53 was noted to increase in papillomas with time. All samples have been shown to harbour HPV 11, but no other HPV types.

Adult↗
PubMed1997

Carcinomas occurring in papillomas of the nasal septum associated with human papilloma virus (HPV).

Carcinomas arising in pre-existing sinonasal papillomas of the nasal septum are rare. To our knowledge only one case has been reported. We report two cases of carcinomas occurring in septal papillomas. In the first case a carcinoma developed in an exophytic papilloma 16 years after the first operation for a papilloma. In the second case a carcinoma was present at the first presentation within an inverted papilloma, and a metastasis had also developed. In the first case HPV type 6/11 was demonstrated by in-situ hybridisation and PCR in the original papilloma as well as in the recurrent papilloma and in the carcinoma. In the second case HPV type 18 was found in the nasal lesion as well as in the metastasis. All samples were examined for Epstein-Barr virus (EBV) by PCR, but with negative results. We believe that case one is the first reported case of carcinomatous transformation within an exophytic septal papilloma.

Adult↗
PubMed1995

Human papillomavirus (HPV) is rarely present in normal oral and nasal mucosa.

The association between human papillomavirus (HPV) and cervical carcinomas is well known. HPV has been found in oral carcinomas and paranasal papillomas, and the question of a causal role of HPV has yet to be answered. Reports on the frequency of HPV in oral and paranasal sinus tumours should be considered in relation to the frequency of HPV in normal oral and nasal mucosa. In the present study 61 normal individual had oral smears taken and 48 had nasal smears. These were examined for HPV by DNA amplification with HPV consensus primers. HPV was not found in the oral mucosa, while a single individual harboured HPV in the nasal mucosa. It is concluded that HPV is rarely present in normal oral and nasal mucosa.

Adult↗
PubMed1995

Human papillomavirus (HPV) in sinonasal papillomas: a study of 78 cases using in situ hybridization and polymerase chain reaction.

To determine the role of human papillomavirus (HPV) in the etiology of sinonasal papillomas, 57 inverted papillomas including 5 cases associated with carcinomas, 16 exophytic papillomas, and 5 cases of columnar cell papillomas were examined for the presence of HPV DNA by in situ hybridization and polymerase chain reaction (PCR). The genetic studies were performed on the formalin-fixed, paraffin-embedded material. In only 6% of the 52 benign inverted papillomas was HPV DNA identified, whereas 69% of the exophytic papillomas were infected by HPV DNA. In none of the 5 cases with columnar cell papillomas could HPV be demonstrated. HPV 6/11 was identified in all of these HPV-positive cases. In the carcinoma area, HPV was detected in 2 (1 HPV 6/11 and 1 HPV 18) of the 5 inverted papillomas associated with carcinomas. The findings confirm the presence of HPV DNA in sinonasal papillomas. The results also indicate that HPV 6/11 may be involved in the pathogenesis of, solely, exophytic papillomas. We found that in situ hybridization and PCR seem equally sensitive in detecting HPV in sinonasal papillomas.

Carcinoma, Squamous Cell↗
PubMed1995

Sinonasal papillomas: a report of 82 cases in Copenhagen County, including a longitudinal epidemiological and clinical study.

The present epidemiological and clinical study comprises 82 patients with sinonasal papillomas diagnosed from 1975 to 1993. Histology showed 58 cases of inverted papillomas including 5 cases of associated carcinoma, 19 cases of exophytic papilloma, and 5 cases of columnar cell papilloma. The incidence of sinonasal papillomas in Copenhagen County was 0.74 per 100,000 inhabitants per year. The inverted and columnar cell papillomas were typically located in the middle meatus with a varying degree of involvement of the adjacent sinuses. The exophytic papillomas were predominantly located multicentrically on the nasal septum. Good results of treatment, especially with regard to inverted papillomas, were not correlated to the aggressiveness of surgery. A lateral rhinotomy with medial maxillectomy was performed as primary surgery in 28 patients. In 50% of these patients there were recurrences. The preliminary results of endonasal endoscopic surgery revealed a high success rate, i.e., no recurrences in 5 cases so far. The septal papillomas were typically resected by a simple endonasal procedure. There were recurrences in 66% of these cases. The midfacial degloving procedure may be advocated instead of or as a supplement to the lateral rhinotomy if the tumor cannot be visualized sufficiently by endoscopy. Smoking may dispose to sinonasal papillomas.

Adolescent↗
PubMed1995

Modified midfacial degloving. A practical approach to extensive bilateral benign tumours of the nasal cavity and paranasal sinuses.

Midfacial degloving is a well-known technique for entering the nasal and paranasal cavities, the rhinopharynx and the base of the skull. We report our experience with a modification of midfacial degloving, applied to two patients with extensive bilateral benign tumours in the nasal cavities and the paranasal sinuses. No rhinoplastic procedure is necessary in this modification, and the access to the upper part of the nasal cavity is improved.

Adult↗
PubMed1994

Human papillomavirus and normal nasal mucosa: detection of human papillomavirus DNA in normal nasal mucosa biopsies by polymerase chain reaction and in situ hybridization.

To determine a possible etiological role of human papillomavirus (HPV) in sinonasal papillomas and squamous cell carcinomas, it is necessary to investigate normal nasal mucosa of healthy persons for the presence of HPV. The material in the present study consists of 21 biopsies taken from the inferior concha of 21 otherwise healthy persons who underwent surgery for nose fractures or nasoseptal deviations. In addition, five inferior conchae were obtained from persons who had died of non-neoplastic diseases. HPV was not detected in any of these specimens, either by polymerase chain reaction or by in situ hybridization. Histologic evaluation showed that squamous metaplasia was a common finding in the biopsies. The presence of HPV in sinonasal papillomas and carcinomas may indicate that HPV is an etiological factor in these lesions.

Adolescent↗