Ganglion cell loss continues during hair cell regeneration

Hair cells and ganglion cells were counted in young adult quail (Coturnix coturnix) after acoustic trauma at 10, 30, 60 and 90 day survival times. Following sacrifice the basilar papillae, along with the ganglia, were fixed, embedded in plastic and sectioned serially at 100 mu intervals from basal to apical tip. Hair cells and ganglion cells were counted from 3 mu thick sections at each interval. Hair cells were designated as tall or short within the area 30-70% of length from basal tip of the papilla. Both tall and short hair cells were significantly reduced in number 10 days following trauma. Tall hair cells recovered to within 96% of normal after 60-90 days. Short hair cells recovered but to a lesser extent. Ganglion cell loss did not begin until 30 days after trauma and continued without recovery 90 days after trauma. A good correlation was found for position of both types of hair cell loss and position of ganglion cell loss. These results suggest that the initial loss of hair cells, both tall and short, results in retrograde degeneration of neural fibers and ganglion cells.     

Carboplatin-radiation interaction in squamous cell carcinoma cell lines.

Chemoradiotherapy has been considered one of the most promising improvements in the treatment of advanced head and neck cancer. This article describes in vitro chemosensitivity to carboplatin in five squamous cell carcinoma cell lines established from head and neck cancers and in one vulvar squamous cell carcinoma cell line. Sensitivity to carboplatin was found to vary markedly when using the 96-well plate clonogenic assay and continuous drug exposure. The difference in carboplatin response between the most sensitive and the most resistant cell lines was fourfold. No cross-resistance was observed between inherent radiosensitivity and chemosensitivity. Effects of concomitant use of carboplatin and radiation were further investigated in the two cell lines that were found to be most sensitive to carboplatin. The drug was administered 1 hour before acute radiation doses, and an additive effect was observed in both cell lines.     

Langerhans cell related inflammatory reaction in laryngeal squamous cell carcinoma

The major cells involved in cancer cell kill are the T lymphocytes. However, T cells need to be activated upon antigen presentation, which is mediated by the antigen presenting cells, one of which is the Langerhans cell (LC). The purpose of this study was to assess the significance of LC and inflammatory cell infiltration in the laryngeal squamous cell carcinoma (LSCC). Forty-five patients who were operated on for LSCC between 1992 and 1999 were included in the study. The clinical and histopathological features of the patients were reviewed. A semiquantitative estimation of the lymphocyte dominant inflammatory reaction within and around the tumor was performed. Anti S-100 antibodies were used for immunohistochemical detection of LCs. Horseradish peroxidase method was used. LCs were present in almost all of the specimens within and around the tumor tissue. The S-100 results did not associate with grade, T and N stages, tumor stage, laryngeal site of involvement and survival (P>0.05). The S-100 results significantly associated with inflammatory reaction in the tumor tissue (P<0.01). In conclusion, the LC related response is not important to inhibit regional metastasis by cancer cells. The LC is not a reliable tool to determine prognosis of the patients with LSCC in the clinical practice.     

Merkel cell carcinoma

PURPOSE: To determine the natural history and treatment outcomes for patients with Merkel cell carcinoma. METHODS: Review of the literature. RESULTS: The probability of regional node involvement at presentation exceeds 50%; few patients present with distant metastases. Comprehensive treatment of the primary site and regional lymphatics with surgery or radiotherapy results in the highest likelihood of cure. The role of adjuvant chemotherapy remains investigational. CONCLUSION: The probability of regional dissemination at diagnosis is high. The optimal treatment is resection of the primary tumor and treatment of the regional lymphatics. Resection of all gross tumor should be accomplished followed by local-regional radiotherapy in most patients.     

Hair cell re-growth

Hair cell loss is usually a function of age, noise, ototoxic drugs and genetics. Therapeutic strategies fall into two categories: protection and regeneration. Protective methods include targeted application of growth factors and other agents to promote cell survival, and systemic application of drugs to prevent activation of programmed cell death. These strategies are related to treatments that cause predictable damage, such as the use of aminoglycoside antibiotics. The challenge of hair cell regeneration is more difficult. Instead of preventing cell loss, we must consider methods of stimulating cell division and hair cell differentiation from existing cells. We need to know much more about the molecular mechanisms that govern these processes so that we can identify potential targets for specific drugs or gene therapies. One method of approaching the issue is to combine in vitro models of developing hair cells with genomic and proteomic technologies. The benefits of hair cell re-growth may not be limited to full replacement of pre-existing cells. Surrogate hair cells may help to maintain cochlear innervation, even if they do not detect sound, and this property could be harnessed to improve the performance of cochlear implants.     

Granular cell tumor

The granular cell tumor (GCT) or Abrikossoff tumor is a neurogenic tumor often benign with a predominant cervicofacial localization. The mean age of onset ranges between 40 and 60 years of age. Female patients are twice more affected. It is a rare tumor (0.019 to 0.03% of all tumors). The prognosis is usually favorable after surgical excision. The histological aspect is usually specific. Nevertheless, the tumor may be mistaken for a malignant one, especially in case of shallow biopsy. The neurogenic markers and staining by periodic acid Schiff (PAS) help to make the diagnosis. The malignant forms with typical recurrence and metastases are extremely rare and require a wide excision.     

Immunohistological study of the nasal mucosa in allergic rhinitis with reference to B cell, T cell subpopulation, activated T cell and Langerhans cell

Distribution of B lymphocytes, T lymphocytes subpopulations, activated T lymphocytes and Langerhans cells of the nasal mucosa in 28 patients with nasal allergy ranging in age from 19 years to 54 years was studied. The specimens from inferior turbinates were frozen at -70 degrees C and sliced at a thickness of 4 microns by cryostat. Monoclonal antibodies and peroxidase-antiperoxidase staining (Ortho) were used to detect these cells. OKT4, OKT8, OKT6 and OKB19 were used as markers of helper/inducer T cells, suppresser/cytotoxic T cells, Langerhans cells and B cells, respectively. OKDR was used as a marker of activated T cells, B cells, Langerhans cells and macrophages. Many OKT4 and OKT8 positive cells were observed in lamina propria. In every case, more OKT4 positive cells were detected in number than OKT8 positive cells. Some OKB19 positive cells and macrophages were observed in lamina propria, but OKT6 positive cells were not observed. OKDR positive cells were observed in high density, and more OKDR positive cells were detected than OKT4, OKT8 and OKB19 positive cells. Most of the OKDR positive cells were small in size and round in shape. From these results, many T lymphocytes were thought to be activated, and T lymphocytes were thought to play an important role in nasal allergy.     

Degeneration of human respiratory cell ciliary beat in monolayer cell cultures

Summary The degeneration of ciliary beat of human respiratory cells was studied in monolayer cell cultures by using a differential interference microscope equipped with a high speed video system. This method for studying ciliary beat in cell cultures on collagen-coated cover glasses is quite advantageous, because it allows for detailed study of all parts of ciliary function and not just ciliary beat frequency (CBF). In the present study both CBF and ciliary beat amplitude (CBA) were found to decrease continuously from the 1st day after plating but the wave form of ciliary beat did not change. Cultures with high cell density provided better preservation of normal ciliary beat for a longer period. In contrast, ciliary beat degenerated quickly in cultures with low cell density. CBF and CBA in cell cultures less than 5 days after plating were always high, supporting use of these cultures for studies of normal ciliary motility.     

Development of novel radioresistant oral squamous cell carcinoma cell lines.

Objectives. Oral cancer is the most common head and neck cancer with an estimated 2 75 000 new cases in 2002.¹ Currently radiotherapy plays an important role in the management of oral cancer. Rates of radioresistance reported in the literature range from 19–53%.² This wide range of reported rates of radioresistance stems from variation in the definition of a radioresistant tumour. As all tumours in vivo posses a heterogeneous cell population, samples of tumour tissue taken for analysis cannot be guaranteed to have originated from a radioresistant subpopulation. These, and other factors, cause the discrepancy in resistance rates. This study aimed to address these issues by creating novel radioresistant cell lines. Method. Two oral cancer cell lines were studied. They were divided into two samples and cultured in identical conditions. Initial dose response curves and survival fractions were calculated for each at the outset of the study. One sample was then exposed to a course of fractionated radiotherapy at 4 Gy increments on a fortnightly basis whilst the other was cultured without exposure. Dose response curves were then constructed for the two daughter samples. Results. Each daughter cell line was found to survive doses of radiotherapy in excess of their parental counterpart. The LD₅₀ (lethal dose killing 50% of cells) was 5.85 Gy for the daughter cell line and 0.91Gy for the parental cells. Conclusions. We have created two radioresistant oral squamous cell carcinoma cell lines to allow further analysis to be performed on readily available proven radioresistant oral cancer cell lines. References 1 Parkin D.M., Bray F., Ferlay J. et al. (2005) Global Cancer Statistics, 2002. CA Cancer J Clin, 55, 74–108 2 Eckardt A., Barth E.L., Kokemueller H. et al. (2004) Recurrent carcinoma of the head and neck: treatment stratergies and survival analysis in a 20‐year period. Oral Oncology, 40, 427–32     

Human endothelial cell growth factors derived from thyroid anaplastic cell carcinoma

Human endothelial cell growth factors were partially isolated from transplanted thyroid anaplastic cell carcinoma propagated in nude mice. Purification was monitored in human umbilical cord vein endothelial cell cultures by (3H)-thymidine incorporation into DNA. Crude tumor extracts with 0.1 M Tris-HCl, pH 7.2 were fractionated by ammonium sulfate precipitation. The active materials precipitated by 35% to 50% ammonium sulfate were further purified by Bio-Rex 70 (Bio-Rad, Richmond, Calif.) cation exchange chromatography. Active fractions eluted by 0.5 M to 0.7 M NaCl were further analyzed via heparin-sepharose affinity chromatography. This resulted in separation of one major peak eluted by 0.9 M to 1.2 M NaCl and confirmed to promote human umbilical cord vein endothelial cell proliferations, and three other peaks. The molecular weight determination of the most active fraction performed by high-pressure liquid chromatography utilizing TSK 2000 gel column indicates 41,000 and 19,000 daltons for the active materials, respectively. Our results demonstrate that the angiogenesis properties of a solid tumor (thyroid anaplastic cell carcinoma), are not composed of a simple mechanism in vivo.     

Small cell epidermoid carcinoma of salivary glands. 'Pseudo'-oat cell carcinoma

Two patients had small cell carcinomas of the salivary glands, with pathological features indicating squamous differentiation, heretofore not described. One is free of disease at seven years, and the second is alive, with regional metastases at four years. Sections from one tumor were studied by electron microscopy and revealed tonofilaments and desmosomes. Most cases of small cell carcinomas of the salivary glands have been considered akin to bronchogenic oat cell carcinoma. Their less aggressive behavior, however, suggests that at least some of these tumors were not true oat cell carcinomas. Our findings, and those of others, indicate that small cell carcinomas of the salivary glands (or head and neck) represent a heterogeneous group. Electron microscopy should be used to determine the exact nature of these neoplasms. If an oat cell nature is ruled out, local and regional treatment should be aggressive, since small cell carcinomas other than oat cell appear not to have a dismal prognosis.     

TPA处理增强喉鳞状细胞癌细胞株 Hep-2细胞的增殖

目的：探讨TPA对体外培养的人喉鳞状细胞癌细胞株HEp-2细胞的作用。方法：应用不同浓度TPA处理体外培养的HEp-2细胞,MTT法检测HEp-2细胞的存活比率。结果：HEp-2细胞经TPA处理后其细胞增殖能力呈现峰型,高峰出现在10μg／L水平上,此时处理细胞的增殖能力是对照组的1．3～1．4倍。随着TPA浓度的增高,HEp-2细胞的增殖能力逐渐下降。结论：TPA处理可以增强HEp-2细胞的增殖能力。