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At least 1,621 records · Page 90Linked to original sources
PubMed2000

Localization of beta and gamma subunits of ENaC in sensory nerve endings in the rat foot pad.

The molecular mechanisms underlying mechanoelectrical transduction and the receptors that detect light touch remain uncertain. Studies in Caenorhabditis elegans suggest that members of the DEG/ENaC cation channel family may be mechanoreceptors. Therefore, we tested the hypothesis that subunits of the mammalian epithelial Na(+) channel (ENaC) family are expressed in touch receptors in rat hairless skin. We detected betaENaC and gammaENaC, but not alphaENaC transcripts in cervical and lumbar dorsal root ganglia (DRG). Using immunofluorescence, we found betaENaC and gammaENaC expressed in medium to large lumbar DRG neurons. Moreover, we detected these two subunits in Merkel cell-neurite complexes, Meissner-like corpuscles, and small lamellated corpuscles, specialized mechanosensory structures of the skin. Within these structures, betaENaC and gammaENaC were localized in the nerve fibers believed to contain the sensors responsive to mechanical stress. Thus beta and gammaENaC subunits are good candidates as components of the molecular sensor that detects touch.

Animals↗
PubMed2001

Genetics of nonmelanoma skin cancer.

Cancer is in essence a genetic disease characterized by genomic instability. Unlike classic genetic syndromes in which a single inherited mutation is often sufficient to determine the perturbed phenotype, most cancers, especially solid tumors, develop after an accumulation of multiple genetic lesions. Inherited mutations that predispose individuals to cancer formation are termed germline, while acquired mutations that contribute to tumor development are designated somatic. Bona fide hereditary cancers account for only a small proportion of all documented cancers. Most tumors result from mutations caused by inherent infidelities in DNA replication, carcinogens, or defects in the DNA reparative apparatus. When mutations occur in critical growth regulatory genes, variations in cellular proliferation and survival contribute to the selection of dominant tumor population(s). Furthermore, these mutations may alter the antigenic properties of the cancerous cell and encourage escape from the host response. Thus, cancer is evolution at the microscopic level.

Carcinoma, Adenoid Cystic↗
PubMed1996

An isolated rat vibrissal preparation with stable responses of slowly adapting mechanoreceptors.

Sinus hairs were isolated from rats and examined in an isolated organ bath while superfused with oxygenated synthetic interstitial fluid. The distal end of the deep vibrissal nerve was teased for single unit recordings of responses from slowly adapting mechanoreceptors to standard bending of the hair. Sinus hair type I and type II receptors could be clearly identified by their respective characteristic firing pattern. Their responses were stable for at least 5 h even if the sinus hair had been stored at 4 degrees C for 24 h beforehand. Electron microscopic examination of these hairs at the end of experiments showed well preserved ultrastructure without abnormalities. The short diffusion distances in this preparation make it well suited for studying drug effects with the aim of investigating the mechanoelectric transduction process in these receptors.

Animals↗
PubMedDate not supplied

Mohs micrographic surgery and the otolaryngologist.

OBJECTIVE: The purpose of this study was to provide an update and overview of the current indications for Mohs micrographic surgery (MMS) for cutaneous and upper aerodigestive tract malignancies. STUDY DESIGN: Literature review. METHODS: A comprehensive review of the literature from 1971 to present was completed by using the Medline data base. In addition, interviews were obtained with several otolaryngologists who had used the technique. RESULTS: MMS offers a superior alternative to standard excision in a variety of cutaneous malignancies. Overall, for the skin cancers likely to be encountered by the otolaryngologist, there is significant evidence that MMS offers increased rates of cure as well as tissue conservation. The role of MMS in upper aerodigestive tract malignancies continues to evolve and multiple issues must be addressed before its general application. CONCLUSIONS: When confronted with a difficult cutaneous malignancy, the otolaryngologist should consider MMS to optimize treatment results.

Carcinoma↗
PubMed1998

Nonmelanoma skin cancer.

Nonmelanoma skin cancers encompass a vast array of malignancies: adventitial, vascular, neuroendocrine, hematologic, adnexal, and epithelial. The skin is also a major site for metastasis of internal disease. With an understanding of the frequency of presentation, clinical distribution, and appearance, the clinician is able to provide an accurate diagnosis for most lesions. Because there are so many nonmelanoma skin cancers, the focus here is on those with a high frequency or significant morbidity. The treatment of nonmelanoma skin cancer is constantly evolving; therefore, emphasis is on diagnosis.

Adenocarcinoma, Sebaceous↗
PubMed1989

Evaluation of prior primary malignancy as a determinant of uveal melanoma. A case-control study.

To examine whether individuals with a history of malignancy are at increased risk for uveal melanoma developing, the authors conducted a case-control study comparing history of prior malignancy among 197 New England cases and 385 matched controls identified by random digit dialing (RDD), and 337 cases residing within the United States and 800 sibling controls. Estimated relative risks for uveal melanoma associated with nonskin cancers were 1.2 (95% confidence interval [Cl], 0.61-2.3) and 0.9 (95% Cl, 0.49-1.5) for RDD and sibling comparisons, respectively. Prior skin malignancy (melanoma and basal or squamous cell types) tended to increase the estimated risk in both groups (case/RDD comparison: relative risk, 1.5; 95% Cl, 0.67-3.5 and case/sibling comparison: relative risk, 1.7; 95% Cl, 0.93-2.9). Among females, history of a malignancy was associated with a higher risk in the case/RDD comparison only (relative risk estimate, 2.2; 95% Cl, 0.97-5.1). These results suggest that the association of prior malignancies with uveal melanoma is weak. Cutaneous malignancies and uveal melanomas may share some common risk factors.

Basal Cell Carcinoma↗
PubMed2003

[Cutaneous neoplasms].

The skin is the organ most commonly affected by malignancies. Various cancers of the skin show a dramatic increase in incidence over the last decades. Epithelial skin tumors are most frequently, e.g., basal cell carcinoma and the squamous cell carcinoma with its precursors, the actinic keratoses. Melanoma, which is extremely difficult to treat in advanced tumor stages, is dreaded. Besides that, there are other epithelial malignant diseases, e.g. Morbus Bowen and adnexal tumors originating from the skin appendices. Mesenchymal malignant neoplasias such as Morbus Kaposi, angiosarcomas and other dermal sarcomas, are rare. Since the majority of malignant neoplasms is removable and curable by a simple surgical intervention, the knowledge of the different skin tumors is essential for non-dermatologist.

Adjuvants, Immunologic↗
PubMed2003

Role of modern radiotherapy in treating skin cancer.

Radiotherapy is an important modality in the treatment of non-melanoma skin cancers. While the majority of patients will be adequately treated without the need for radiotherapy, there are factors that may favour a recommendation for radiotherapy. The established roles of modern radiotherapy include the definitive, adjuvant and palliative settings. It is important that clinicians treating skin cancers have an understanding and awareness of these roles. The aim of this article is to present an overview of radiotherapy in the current Australian setting.

Aged↗
PubMed2006

Non-Hodgkin lymphoma and skin cancer: A dangerous combination.

There is a significant association between non-Hodgkin lymphoma, including chronic lymphocytic leukaemia, and both melanoma and non-melanoma skin cancer. This review highlights the existing data on the phenomenon of accelerated skin cancer in patients with non-Hodgkin lymphoma and specifically chronic lymphocytic leukaemia. The outcomes of patients with non-Hodgkin lymphoma (including chronic lymphocytic leukaemia) and non-melanoma skin cancer are worse than in patients without concomitant lymphoreticular malignancy, as shown by increased rates of local recurrence, regional metastasis and death. Pathogenic factors may be common between non-Hodgkin lymphoma and chronic lymphocytic leukaemia and skin cancer. The treatment of skin cancer in patients with non-Hodgkin lymphoma must factor in the worse prognosis and adapt standard therapeutic approaches to minimize the risk of metastasis and death. Preventive strategies and early detection are paramount in this high-risk population.

Basal Cell Carcinoma↗
PubMed2006

How we do it: Chemo-electroporation in the head and neck for otherwise untreatable patients.

Keypoints * Chemo-electroporation therapy with bleomycin is a locoregional treatment modality for head and neck and skin cancer, with the potential to preserve function. * In our institution, chemo-electroporation therapy is used for patients that can no longer be treated by surgery or radiotherapy, or for whom surgical treatment would be very extensive and thus declined by the patient. * This paper describes in detail the technique of bleomycin-electroporation therapy. The literature is reviewed and preliminary results of the clinical trial are presented. * The main focus of the trial is to determine the safety, effectiveness, and burden of bleomycin-electroporation therapy for the patient. * All 17 tumours responded to therapy. Local tumour control was reached in 14 of the 17 (82.4 %) tumours. * Based on the outcome of the clinical trial, bleomycin-electroporation therapy has the potential to become a valuable addition to the late-stage treatment options for patients with head and neck or skin tumours.

Adenocarcinoma↗
PubMed1997

Island chondromucosal flap from the nose in reconstruction of the eyelid. A light and scanning electron microscopic study.

Specimens from the reconstructed eyelids of two out of 15 patients operated on using an island chondromucosal flap from the nose were observed under light and scanning electron microscopy (EM) to study the histological and ultrastructural features of nasal epithelium transferred as a flap to the lids, the microscopic appearance of the other tissues of the flap, and its vascularisation. Both light and scanning EM images showed that nasal epithelium, when transferred as part of a flap for reconstruction of the eyelid, maintains its differentiation for many months. The lumen of arteries and veins can be observed in sagittal sections within the flap, suggesting that their course is parallel to its long axis. The absence of fibrosis or muscle fibre degeneration together with a highly cellular cartilage are indirect indications of good vascularity. These data support the reliability of the island chondromucosal flap from the nose in reconstruction of the eyelid.

Aged↗
PubMedDate not supplied

Cutaneous neoplasms in renal transplant recipients.

Cutaneous neoplasms are much more common in renal transplant recipients than in the general population, and are the most common malignancies in these patients. This is the case with basal cell carcinoma, and even more so with squamous cell carcinoma. Many risk factors for development of such malignancies are similar to those in the general population. However, in the transplant population, such cancers appear at an earlier age, behave more aggressively, and frequently appear at multiple sites. Therefore, diligence on the part of the patient and on the part of his or her health care providers is of utmost importance. Treatment options include reduction in immunosuppression, but preventive maintenance remains the primary focus of efforts to limit these malignancies.

Basal Cell Carcinoma↗
PubMed1990

[Duration of eyelid suture following tarso-conjunctival transposition].

Temporary closure of the lids is an obvious handicap for elderly tumor patients after the first step of the modified Hughes' tarsoconjunctival flap. So far, it has been suggested that the duration of lid closure should be between 2 weeks and 3 months. We report on 36 patients who were operated on between 1984 and 1989. In 16 patients, the lids were divided after 3 weeks. In another 13 patients, they were divided up to the end of the 5th week postoperatively. Neither dehiscence of the wounds nor tissue necrosis appeared. No progressive lowering of the lid margin occurred. This observation suggests that division of the lids can be performed without risk after 3 to 4 weeks.

Adolescent↗
PubMed1990

[Neuro-endocrine carcinoma of a Bartholin's gland].

This is a case of a 38 year old woman in whom a small basophil cell tumour occurred with inguinal and iliac lymph node metastases followed by pulmonary metastases and extension of the tumour into the vagina and the bladder. The patient died eight months after having started multiple chemotherapy and radiotherapy with telecobalt. Extra studies were carried out ten years later on the cells. This made it possible to diagnose the condition as a neuro-endocrine carcinoma rich in serotonin.

Adult↗
PubMed1998

[Non-melanomatous malignant skin tumors of the hand].

Non-melanomatous malignant skin tumors of the hand are the same as those observed on other parts of the body, but with specific characteristics of frequency, aetiology, site and sometimes misleading clinical features. The author analyses these characteristics in relation to precancerous tumors: solar keratoses, arsenical keratoses, radiation dermatitis, kerato-acanthomas, Bowen's disease and malignant tumors: basal cell, squamous cell and other rarer carcinomas. He then outlines the principles of surgical treatment with reference to anaesthesia, usually local or regional, and resection, whose extent and depth depend on the nature and site of the lesion.

Acrospiroma↗
PubMed1995

Solid tumors after heart transplantation: lethality of lung cancer.

BACKGROUND: Prolonged nonspecific immunosuppression after solid-organ transplantation is associated with an increased risk of certain cancers. This study examined the development of solid-organ tumors after cardiac transplantation. METHODS: Thirty-eight solid tumors were identified in 36 (5.9%) of 608 cardiac transplant recipients who survived more than 30 days. Two patients had two types of skin tumors (basal cell and squamous cell). The tumors included the following types: skin (15), lung (10), breast (1), bladder (2), larynx (2), liver (1), parotid (1), testicle (1), uterus (2), melanoma (2), and Merkel's cell (1). Four immunosuppression regimens based on cyclosporin A or FK 506 were used during this period. RESULTS: There was no association between the incidence of solid tumors and the use of lympholytic therapy. After the diagnosis of tumor was made, the actuarial 2-year survival rates of recipients with skin, lung, and other solid tumors were 71%, 22%, and 23%, respectively. Eight of 10 patients with lung cancer were in stage IIIA or higher at the time of diagnosis. CONCLUSION: Skin and lung tumors are the most frequent solid tumors in heart transplant recipients. Skin tumors (except Merkel's cell carcinoma and melanoma) usually have a benign course, whereas lung and other tumors developing in cardiac transplant recipients carry a poor prognosis. Advanced disease stage at the time of diagnosis is responsible for the dismal outcome of recipients in whom solid tumors develop. Close postoperative tumor surveillance after cardiac transplantation is warranted.

Actuarial Analysis↗