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81.
BACKGROUND: Basal cell carcinoma, or BCC, is a malignant epithelial tumor of the skin, commonly seen in the head and neck. Because dentists routinely evaluate the head and neck, the authors present three examples of BCC of the face and jaw to help clinicians recognize the condition. They also provide a literature review regarding BCC's etiology, classification, treatment and prevention. DESCRIPTION OF THE DISEASE: Sun exposure plays an important role in the development of BCC. The most susceptible people are those with minimal skin pigmentation. BCC is more frequently seen in men than in women. The most common form of BCC is the nodular type, which, if untreated, eventually ulcerates and may result in extensive local tissue destruction. The three cases described in this article highlight the range of BCC severity. CLINICAL IMPLICATIONS: Oral health care providers may play an important role in the recognition and diagnosis of BCC involving the head and neck. Early recognition and diagnosis may lead to management that results in improved cure rates, with reduced morbidity and reduced treatment costs. 相似文献
82.
Traumatic spinal cord injury is a devastating condition that alters every aspect of the victim's life. Motor vehicle accidents cause about half of the cases, whereas others are the result of falls, recreational and sporting accidents, or acts of violence. We report a case of a C3 spinal fracture with a resultant Brown Sequard syndrome, which occurred in a unique manner and could have easily been prevented. There is a need for the medical community to play a more active role in educating the public to prevent accidents that lead to these catastrophic injuries. 相似文献
83.
James HJ Sharer LR Zhang Q Wang HG Epstein LG Reed JC Gelbard HA 《Neuropathology and applied neurobiology》1999,25(5):380-386
Apoptosis of neurones, macrophages, and microglia occurs in the brains of paediatric patients with human immunodeficiency virus (HIV) type 1 encephalitis, which is often associated with pre-mortem neurological disease (progressive encephalopathy). We have previously reported that TUNEL-positive neurones in brain tissue from paediatric patients with HIV type 1 encephalitis and progressive encephalopathy are strikingly devoid of the pro-apoptotic gene product Bax, in marked contrast to brain-resident macrophages and microglia. Using immunocytochemical methods, the present study demonstrate that neurones in patients with HIV type 1 encephalitis and progressive encephalopathy, as well as macrophages and microglia, but not astrocytes, overexpress caspase-3, a pro-apoptotic enzyme that is proteolytically activated downstream of Bax-Bcl-2 dysregulation. Co-localization of neuronal cytoplasmic caspase-3 and nuclear TUNEL staining, a marker for fragmented DNA, was also infrequently observed in brain tissue from patients with HIV type 1 encephalitis and progressive encephalopathy. These findings suggest that vulnerable neurones in brain tissue from patients with HIV virus type 1 encephalitis and progressive encephalopathy undergo apoptosis by a mechanism that involves upregulation of caspase-3 in a pathway that is independent of Bax-Bcl-2 dysregulation. Furthermore, caspase-3 upregulation in apoptotic neurones likely occurs prior to DNA fragmentation. 相似文献
84.
Long-term effects of finasteride on prostate tissue composition 总被引:11,自引:0,他引:11
Marks LS Partin AW Dorey FJ Gormley GJ Epstein JI Garris JB Macairan ML Shery ED Santos PB Stoner E deKernion JB 《Urology》1999,53(3):574-580
OBJECTIVES: To determine the long-term effects of finasteride treatment on prostate tissue composition; to relate these effects to clinical outcomes; and to test the hypothesis that finasteride exerts a selective or preferential action on the transition zone. METHODS: Nineteen men with symptomatic benign prostatic hyperplasia (BPH) who completed a 6-month double-blind trial of finasteride were enrolled in a 24-month open-label extension study of drug responders. Magnetic resonance imaging and prostate biopsy for morphometric analysis were performed together 70 times: at baseline (n = 19), after treatment periods of intermediate duration (6 to 18 months, n = 32), and after long-term drug treatment (24 to 30 months, n = 19). At baseline, prostate volume averaged 51 cc, of which 57% was transition zone. RESULTS: Decreases in symptom score, dihydrotestosterone and prostate-specific antigen levels, and prostate volume occurred at 6 months (P <0.01), stabilized, and were maintained without further long-term decreases. Prostate epithelium contracted progressively from baseline (19.2% tissue composition; 6.0-cc volume; 3.2 stroma/epithelial ratio) to intermediate (12.5%, 3.3 cc, and 5.6, respectively) to long-term treatment (6.4%, 2.0 cc, and 17.4, respectively, P <0.01 for all). Percent epithelial contraction was similar in the peripheral and transition zones (P = NS). The transition zone remained a relatively constant proportion (53% to 58%) of whole-prostate volume from baseline to long-term observation. CONCLUSIONS: Long-term finasteride treatment (24 to 30 months) results in a marked involution of the prostate epithelium, which continues to progress for many months after clinical effects stabilize. The effect on the epithelium is similar in the peripheral and transition zones for both morphometric and volumetric changes. Progressive contraction of the prostate epithelium appears to constitute the underlying mechanism for sustained action of finasteride. 相似文献
85.
86.
Brat DJ Wills ML Lecksell KL Epstein JI 《The American journal of surgical pathology》1999,23(3):257-262
The authors determined whether clinically relevant diagnostic information would be lost by examination of <3 levels per tissue core in prostate needle biopsy specimens. They evaluated 439 consecutive sextant biopsy specimens for the following three histopathologic features: presence of adenocarcinoma involving one core, Gleason pattern 4 in cases of grade 3 + 4 = 7 adenocarcinoma, and perineural invasion (PNI) by carcinoma. For all cases, 3 levels from each involved core were reviewed for the presence or absence of these three features. In 50 cases with adenocarcinoma involving only 1 core, diagnostic carcinoma was present on all 3 levels in 43 cores (86%). Carcinoma was present on only 2 levels in 3 cores (6%), present only on 1 level in 3 cores (6%), and present only on additional cut-downs, not on the original 3 levels in 1 core (2%). Among 32 cases, 51 cores were identified that contained Gleason grade 3 + 4 = 7 adenocarcinoma. In 41 cores (80%), pattern 4 was identified in all 3 levels. In 5 cores (10%), pattern 4 was identified on only 2 levels, and in another 5 cores (10%), pattern 4 was present on only 1 level. Among 36 cases, 69 tissue cores were identified that contained perineural invasion (PNI). In 54 cores (78%), PNI was present on all 3 levels. In 7 cores (10%), PNI was present on only 2 of 3 levels, while in 7 other cores (10%), PNI was present on only 1 of 3 levels. In 1 core (1.5%), PNI was noted only on additional cutdowns, not on the original 3 levels. We estimated that reducing the number of levels to 1 per core could result in the misdiagnosis of PNI, grading, or carcinoma in approximately 8-11% of cores with these features and could have changed the case diagnosis in 9 of 439 cases. If only 2 levels were reviewed, we predict misdiagnosis in 5% to 6% of cores with these features and a change in the case diagnosis in 5 of 439 cases. Misdiagnosis of clinically relevant features on prostate biopsy specimens can be minimized with histologic review of 3 levels per tissue core. 相似文献
87.
PURPOSE: To report a new eyedrop dispensing container that allows administration of eyedrops while the head of the patient is in the usual upright position. METHODS: An eyedrop dispensing container with a dip tube extending to the bottom, an automatic venting mechanism, and an angulated dispensing tube was developed. RESULTS: The problem of unwanted efflux of fluid was solved by incorporating the automatic venting mechanism. The final design includes an adjustable, angulated dispensing tube and "single structure" construction incorporating the cap. A removable cheek rest is also provided. The design allows eyedrops to be instilled while the patient's head is in the upright position and even when spectacles are being worn. A prototype 15-ml bottle delivered an eyedrop volume of 19.7+/-1.2 microl (mean +/- SD) (n = 75). CONCLUSION: This new eyedrop bottle should allow precise self-administration of eyedrops by a patient in front of a mirror, without a need to change head position. 相似文献
88.
Robert C. Smith Alan W. Partin Jonathan I. Epstein Charles B. Brendler 《The Journal of urology》1996,156(2):454-458
Purpose
The effect of wide excision of the neurovascular bundles on disease-free survival was determined in men with clinically localized prostate cancer and pathological evidence of extensive capsular perforation in the region of the neurovascular bundle.Materials and Methods
We previously analyzed 107 men with clinically localized prostate cancer and pathological evidence of extensive capsular perforation in the region of the neurovascular bundles. Wide excision of the neurovascular bundle on the sides of palpable induration resulted in negative surgical margins in 58 percent of patients compared to only 45 percent in whom the neurovascular bundles were left intact (p = 0.03). At a mean followup of 20 months, median interval to disease recurrence as defined by a measurable PSA level was 33 months in patients whose neurovascular bundle(s) were widely excised versus 22 months in those whose neurovascular bundle(s) were left intact (p = 0.03). However, by 43 months 75 percent of the patients in both groups had a detectable prostate specific antigen and the Kaplan-Meier curves had converged, suggesting that wide excision of the neurovascular bundle(s) did not confer a sustained survival advantage.Results
With an additional followup of 28 months, the probability of having an undetectable prostate specific antigen level at 5 years was 47 percent in patients with negative versus 6 percent with positive surgical margins (p less than 0.001).Conclusions
Our extended followup suggests that some patients with extensive capsular perforation can be rendered free of disease with wide excision of the neurovascular bundle(s). 相似文献89.
Interdependence between cytokines and cell adhesion molecules to induce interleukin-6 production by stromal cells in myeloma 总被引:4,自引:0,他引:4
Bone marrow (BM) environment is thought to support the growth of myeloma cells and thus to play an important role in the pathogenesis of multiple myeloma (MM). Because interleukin-6 (IL-6) is an essential growth factor in MM, we have examined the effects of two myeloma cell lines (U266 and ARH-77) on the IL-6 production by BM stromal cells in a co-culture system. These cell lines strongly stimulate the IL-6 production and IL-6 triggering was partially dependent on physical contact between lines and stroma. The percentages of cell adhesion to stromal layers were 39% and 25% respectively for ARH77 and U266 cell lines. Inhibition studies with blocking monoclonal antibodies showed the importance of CD49d/CD106 and CD11a/CD54 interactions in the stimulation of IL-6 production by stromal cells. However, cell-to-cell contact was not an absolute requirement for IL-6 production. Cytokines, of which TNF-alpha and IL-1beta produced by MM or accessory cells, were also able to stimulate IL-6 production by fibroblasts and show additive effects. In adhesion assays, TNF-alpha and IL-1beta were able to increase the adhesion of MM cells to stromal cells. CD54 was upregulated by IL-1beta, TNF-alpha or a contact with MM cells while CD106 expression was not, suggesting only a functional change of this molecule. However, the role of monoclonal antibodies, directed against these factors, confirmed the role of TNF-alpha in the IL-6 production by stromal cells, while any IL-1beta intervention was not shown in our co-culture system. IL-6 favoured and maintained adhesion of MM cells to stromal cells spontaneously since its reintroduction in the favoured co-culture system restored their decreased adhesion observed on a glutaraldehyde fixed stromal layer. Overall our data suggest a functional overlap between cytokines and adhesion molecules for the paracrine IL-6 production. 相似文献
90.
Missense mutations in the beta-myosin heavy-chain gene cause central core disease in hypertrophic cardiomyopathy. 总被引:9,自引:2,他引:7 下载免费PDF全文
L Fananapazir M C Dalakas F Cyran G Cohn N D Epstein 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(9):3993-3997
Hypertrophic cardiomyopathy (HCM) is an important cause of sudden death in apparently healthy young individuals. In less than half of kindreds with HCM, the disease is linked to the beta-myosin heavy-chain gene locus (MYH7). We have recently described two missense MYH7 gene mutations [Arg-403 to Gln (R403Q) and Leu-908 to Val (L908V)] and found that the mutant message is present in skeletal muscle soleus) and that the mutant beta-myosin obtained from soleus muscle has abnormal in vitro motility activity. Having identified a second kindred with the R403Q mutation, and 3 other kindreds with two additional mutations (G741R and G256E), we performed histochemical analysis of soleus muscle biopsies from 25 HCM patients with one of these four mutations. Light microscopic examination of the NADH-stained biopsies revealed the presence of central core disease (CCD) of skeletal muscle, a rare autosomal dominant nonprogressive myopathy characterized by a predominance of type I "slow" fibers and an absence of mitochondria in the center of many type I fibers. CCD was present in 10 of 13 patients with the L908V mutation, 5 of 8 patients with the R403Q mutation, 1 of 3 patients with the G741R mutation, and 1 patient with the G256E mutation. Mild-to-moderate myopathic changes with muscle fiber hypertrophy were present in 16 patients. Notably, CCD was present in 2 adults and 3 children with the L908V mutation who did not have cardiac hypertrophy. In contrast, soleus muscle samples from 5 patients from 4 kindreds in which HCM was not linked to the MYH7 locus showed no myopathy or CCD. Soleus muscle biopsies from 5 control subjects also showed normal histology. This work demonstrates that (i) MYH7-associated HCM is often a disease of striated muscle but with predominant cardiac involvement and (ii) a subset of HCM patients with MYH7 gene missense mutations have CCD. 相似文献