The Bak protein expression in germinal centers of hypertrophied adenoids in children.

The aim of this study was to evaluate pro-apoptotic Bak expression in the germinal centers of adenoid in children on the assumption of the potential usefulness of Bak as adenoid function marker. The study involved 95 children undergoing adenoidectomy; divided into three age groups: aged up to 5 years (25 children), 5-10 years (54 children) and over 10 years (16 children). The analyzed material was adenoids removed on the ground of hypertrophy. Immunohistochemical analyses were carried out using goat polyclonal Bak antibodies (DAKO) directed against human Bak protein. The presence of Bak positive lymphocytes within germinal centers and Bak immunostaining were scored. The immunohistochemical staining showed the Bak positive lymphocytes mainly within the germinal centers of the lymphoid follicles. The Bak reactivity was also present in hyperplastic lymphoid tissue within the subepithelial B lymphocytes. We have not found statistically significant correlation between Bak expression and clinical status and change in Bak expression level according to age. The apoptotic presence within the germinal centers are the manifestation of which is Bak expression and its lack in the mantle zone, what we confirmed in our former study by describing Bcl-2 expression, seems to be a proper B cells maturation marker within lymphoid follicles. Our finding shows that these processes are not influenced by age and supports our thesis that adenoid involution is rather the effect of changes in the number of lymphoid follicles that changes in them.

The role of Bak expression in apoptosis of the oral squamous cell carcinoma (OSCC) and metastases to lymph nodes (LNMs).

The immunohistochemical method was applied to show Bak expression in oral squamous cell carcinoma and its metastases to lymph nodes (LNMs). Bak expression was evaluated by immunohistochemical methods in specimens with oral squamous cell carcinomas and their lymph node metastases. Immunohistochemical studies were performed, using goat polyclonal Bak antibodies (Santa Cruz Biotechnology, USA) at 1:200 dilution. Our studies revealed over expression (64%) of Bak in the cytoplasm of epithelial cells in primary tumours (PTs) and in (75%) LNMs. No statistically significant correlations were observed between Bak immunoreactivity and age, pT and G of the carcinoma in PTs and LNMs. We conclude that expression of Bak may be useful for better characterising and predicting the prognosis of OSCC but cooperative studies are needed to assess its applications in the clinical practice.

The Bcl-2 protein expression in germinal centers of hypertrophied adenoids in children.

The aim of this study was to evaluate Bcl-2 expression in the germinal centers of adenoid in children on the assumption that it can be treated as a marker of adenoidal tissue function. The study involved 95 children. The patients were divided into three age groups: aged up to 5, 5-10 and above 10 years. The analysed material were adenoids removed on the grounds of hypertrophy. Immunohistochemical analyses were carried out using monoclonal antibodies (DAKO/Bcl-2, No. M0887) directed against human Bcl-2 protein. The presence of Bcl-2 positive lymphocytes within the lymphoid follicles and Bcl-2 immunostaining were scored. The immunohistochemical staining showed Bcl-2 positive lymphocytes in the examined sections of adenoidal tissue and their characteristic location, mainly within the mantle zone. Bcl-2 reactivity was widespread in hyperplastic lymphoid tissue, including germinal centers surroundings, scattered cells within the germinal centers and the T-cell areas in general. We have not found statistically significant correlation between Bcl-2 expression and clinical status and change in Bcl-2 expression level according to age. The apoptosis presence within the germinal centers and its lack in mantle zone, the manifestation of which is Bcl-2 expression, is a sign of a proper lymphocytes maturation within lymphoid follicles. It seems that these processes are not influenced by age, so the adenoid involution is probably associated with the changes in the number of lymphoid follicles rather than change or inhibition of the processes that take place in them.

[Lymphocyte subpopulations in the adenoids analyzed by flow cytometry]. / Ocena subpopulacji limfocytów w przeroslych migdalkach gardlowych metoda cytometrii przeplywowej.

Adenoid hypertrophy is a common problem of childhood. The peak occurrence of adenoid hypertrophy correlates with the onset of serous otitis media. The aim of the study was to evaluate the lymphocyte subpopulations in the adenoids of children with serous otitis media. The adenoids obtained from 65 children at the age of 1 to 17 years were examined. Two groups were studied: 1) children with persistent effusion in the middle ear, 2) children with adenoid hypertrophy without a history of otitis media. The percentage of the lymphocytes B in the adenoids was similar in both groups. However, the percentage of lymphocytes T (p < 0.04), and CD4+ (p < 0.005) was significantly lower in adenoids of children with serous otitis media. The percentage of lymphocytes T HLA-DR+ was slightly higher in this group, but the percentage of lymphocytes T CD25+ was the same in both groups. The quantitative differences in the lymphocyte subpopulations of adenoids may be the predisposing factor in serous otitis media.

Lymphocyte subpopulations in hypertrophied adenoid in children.

Adenoid hypertophy is a common feature of childhood. It is currently accepted that it is caused by the antigen-stimulated increased activity of lymphocyte B (D. Bani, O. Gallo, O. Fini-Storchi, Intraepithelial lymphocyte subpopulations and dendritic accessory cells in normal and hypertrophic adenoids, Laryngoscope 10 (1994) 869-873). The adenoid decreases its size with age but the accompanying function alterations are not fully understood (L. Zawadzka-Glos, M. Chmielik, M. Wasik, Cell mediated response in hypertrophied tonsils in children, Nowa Pediatr. 4 (1997) 12-13). The understanding of the adenoid structure that undergoes some changes during the growth period is essential for evaluation of indications for adnoidectomy and assessment of its potential results. The aim of this study was to evaluate lymphocyte subpopulations in adenoid according to age. The analysed material was adenoids removed on the grounds of hypertrophy, which caused obstructive symptoms and/or otitis media with effusion onset. In the present study, we did not find any statistically significant differences among lymphocytes B, Th, and Ts subpopulations, respectively, in the adenoids of any of the age groups. We have found a statistically significant CD3(+) HLA-DR(+) cell percentage decrease in the group of children from 5 to 10 and above 10 years of age, respectively. We have also found a statistically significant increase in the percentage of NK (CD3(-) CD16(+) 56(+)) lymphocytes in relation to age. On the grounds of the current study, it may be stated that some changes in lymphocyte subpopulations in the adenoid take place with age.

Distortion products otoacoustic emissions in diagnosis of hearing loss in Down syndrome.

This study was carried out to investigate the features of hearing impairment in subjects with Down syndrome. Forty-seven children and 14 adults with Down syndrome were included in the study. In all cases, a complete otorhinolaryngological examination was performed, followed by audiological assessment. Depending on age, intellectual level and middle ear status the following examinations were performed: pure-tone 'play audiometry', tympanometry, acoustic reflex, auditory brain response (ABR) and distortion products otoacoustic emissions (DPOAE). The results were compared with age matched control groups. Among the group of children with Down syndrome, we have frequently found impairment of the conductive function of the middle ear which was expressed by pathological tympanometry. Tympanometry of B and C type was detected in 56% of ears. The amplitude of DPOAE was lower in children with Down syndrome than in the control group. This difference was more expressed in adults with Down syndrome. DPOAE examination results in subjects with Down syndrome without conductive hearing loss indicate early age related inner ear impairment.

[The influence of the middle ear status on the measurement of evoked otoacoustic emissions (DPOAE)]. / Wplyw stanu ucha srodkowego na wywolane emisje otoakustyczne (DPOAE).

The aim of this study was to evaluate the influence of the middle ear status on detection and amplitude of otoacoustic emissions-DPOAE. DPOAE were detected in all healthy ears and their amplitude was between 11.4 and 22.4 dB SPL. Responses at frequencies of 0.5 and 0.75 kHz were not detected in the group of children with Eustachian tube dysfunction in 60% and 27% of ears respectively. The absence of DPOAE responses in the group of children with B type tympanometry was found in 3/4 of the investigated ears at frequencies of 0.5 and 0.75 kHz and in over 50% of ears at frequencies of 1.0 and 8.0 kHz. No influence of cochlear reserve on detection and amplitude of DPOAE was found in the studied group. Conductive hearing loss associated with a presence of negative pressure and effusion in the middle ear inhibits DPOAE detection and causes decrease of otoacoustic emission amplitude.