Cervical lymph node metastasis in squamous cell carcinoma of the buccal mucosa: a retrospective study on pattern of involvement and clinical analysis.

BACKGROUND: The study was performed with an aim to map the pattern of metastasis of squamous cell carcinomas of buccal mucosa to various cervical lymph node levels and analyze its correlation with primary tumor size and histo-pathological grading. MATERIAL AND METHODS: 254 patients with squamous cell carcinoma of the buccal mucosa treated with surgery first approach were analyzed retrospectively. The tumor size was noted from pre-operative CT Scans and were divided into early and advanced tumors. The resected specimen was studied to note the histo-pathological grading of the squamous cell carcinoma and the metastatic deposits at various lymph node levels. RESULTS: Out of 254 patients (149 females, 105 males), 145 patients showed histo-pathologically proven metastatic deposits in one or more lymph nodes out of which there were 56 patients showing occult metastasis. 78/145 patients showed metastatic involvement of level IB and/or IA lymph nodes, 31 showed involvement of level II and/or I lymph nodes, 27 showed involvement of level III with or without involvement of level I and II and 9 showed metastasis to level IV and V lymph nodes with or without level I, II or III lymph nodes. Cervical lymph node metastasis had statistically significant association with tumor size with advanced tumors showing worse pattern of metastatic spread beyond level I and II lymph nodes. As the degree of differentiation of squamous cell carcinoma reduced, they were more prone for cervical metastasis with moderately and poorly differentiated squamous cell carcinoma showing higher involvement of level III, IV and V lymph nodes. CONCLUSIONS: The majority of buccal mucosa cases showed metastasis to level I, II and III lymph nodes out of which level IB and/or IA was most frequently involved. Metastasis to level IV and V lymph nodes was rare and was seen especially in patients with advanced primary tumor and poor histo-pathologic differentiation.

Transglutaminase 2 overexpression induces depressive-like behavior and impaired TrkB signaling in mice.

Serotonin (5-hydroxytryptamine, 5-HT) and brain-derived neurotrophic factor (BDNF) are two signaling molecules that have important regulatory roles in the development and plasticity of neural circuits that are known to be altered in depression. However, the mechanism by which 5-HT regulates BDNF signaling is unknown. In the present study, we found that 5-HT treatment increases BDNF receptor, TrkB (tropomyosin related kinase B), levels in mouse primary cortical neurons via a Rac1 (RAS-related C3 botulinum toxin substrate 1)-dependent mechanism. Significant increases in the levels of type-2 transglutaminase (TG2, which is implicated in transamidation of 5-HT to Rac1) are observed in the mouse prefrontal cortex (PFC) following chronic exposure to stress. We also found that TG2 levels are increased in the post-mortem PFC of depressed suicide subjects relative to matched controls. Moreover, in mice, neuronal overexpression of TG2 resulted in the atrophy of neurons and reduced levels of TrkB in the PFC as well as a depressive-like phenotype. Overexpression of TG2 in mouse cortical neurons reduced TrkB levels as a result of impaired endocytosis of TrkB. TG2 inhibition by either a viral particle or pharmacological approach attenuated behavioral deficits caused by chronic unpredictable stress. Moreover, the overexpression of TrkB in the mouse PFC ameliorated the depressive-like phenotype of TG2-overexpressed mice. Taken together, these post-mortem and preclinical findings identify TG2 as a critical mediator of the altered TrkB expression and depressive-like behaviors associated with chronic exposure to stress and suggest that TG2 may represent a novel therapeutic target in depression.

Natural history and prognosis of ischemic heart disease.

Forty-four cases with myocardial rupture (33 with free wall rupture, 9 with interventricular septal perforation and 2 with papillary muscle rupture), all of which were ascertained by autopsy and/or at surgery, were analyzed. When the following 7 risk factors were actively managed in the acute stage of myocardial infarction, the incidence of myocardial rupture was significantly reduced: a) high blood pressure on admission, b) physical and emotional instability, c) recurrent chest pain, d) aged females, e) no history of angina or myocardial infarction, f) large myocardial infarction on ECG and g) the first 10 days after the attack of myocardial infarction. If cardiogenic shock occurs, surgery should be performed as soon as possible; if not, it should be delayed 3 weeks. The natural history of ischemic heart disease was analyzed in 400 medically-treated patients with significant coronary artery disease. They had been followed up continuously and periodically for more than one year. The prognosis of the patients with 3-vessel disease or left main trunk disease, those with poor left ventricular function (EF less than 30%) and of old age (greater than or equal to 60) and those who had a history of ischemic heart disease was poor. Follow-up study was done in 30 patients with variant angina. They often had life-threatening arrhythmias during attacks (8 ventricular tachycardia or ventricular fibrillation, 8 serious bradyarrhythmia). All patients with variant angina should be treated medically at first, and only patients with organic coronary artery disease and chest pain on effort in spite of the medical treatment should be considered as candidates for AC bypass surgery.