An Immunohistochemical and Polarizing Microscopic Study of the Tumor Microenvironment in Varying Grades of Oral Squamous Cell Carcinoma

BACKGROUND: Invasion of epithelial cells into the connective tissue brings about massive morphological and architectural changes in the underlying stroma. Myofibroblasts reorganize the stroma to facilitate the movement of tumor cells leading to metastasis. The aim of this study was to determine the number and pattern of distribution of myofibroblasts and the qualitative and quantitative change that they cause in the collagen present in the stroma in various grades of oral squamous cell carcinoma (OSCC). METHODS: The study was divided into two groups with group I (test group, 65 cases) consisting of 29 cases of well-differentiated squamous cell carcinoma, 25 moderately differentiated SCC, and 11 poorly differentiated SCC, and group II (control group) consisting of 11 cases of normal mucosa. Sections from each sample were stained with anti-α-smooth muscle actin (α-SMA) antibodies, hematoxylin and eosin, and Picrosirius red. Several additional sections from each grade of OSCC were stained with Masson's trichrome to observe the changes in collagen. For the statistical analysis, Fisher's exact test, Tukey's post hoc honest significant difference test, ANOVA, and the chi-square test were used, and p < .05 was considered statistically significant. RESULTS: As the tumor stage progressed, an increase in the intensity α-SMA expression was seen, and the network pattern dominated in more dedifferentiated carcinomas. The collagen fibers became thin, loosely packed, and haphazardly aligned with progressing cancer. Additionally, the mean area fraction decreased, and the fibers attained a greenish yellow hue and a weak birefringence when observed using polarizing light microscopy. CONCLUSIONS: Myofibroblasts bring about numerous changes in collagen. As cancer progresses, there isincrease in pathological collagen,which enhances the movement of cells within the stroma.

Comparison of phenylephrine and ephedrine for treating hypotension after spinal anesthesia for cesarean section: a Randomized double-blind clinical trial

Background and objectives: Hypotension following spinal anesthesia [SA] for cesarean delivery can have important consequences for parturient and may affect neonatal outcome. The objective of this study was to compare intravenous bolus doses of phenylephrine and ephedrine to treat hypotension after SA for cesarean section and the effect of vasopressors on fetal outcome in terms of Apgar score. Methodology: Two hundred parturient fulfilling inclusion criteria were r and omly allocated into two groups of hundred each. Lumbar puncture was done in sitting position and 10 mg, 0.5% hyperbaric bupivacaine was given intra-thecally to every patient. All patients were placed supine with 15 degree left lateral tilt position. If hypotension occurred after SA [systolic blood pressure less than 90 mm Hg or decrease in systolic blood pressure more than 20% of base line whichever is lower] was treated with either 100µg phenylephrine in Group A or6 mg ephedrine in Group B boluses given intravenously. Results: Single intravenous bolus dose of phenylephrine 100 µg was effective in treating hypotension in 92% parturient while ephedrine 6mg remained effective in 78% parturient, which was statistically significant [p= 0.0009]. There was no difference in the mean Apgar scores [p = 0.76] at 1 minute and [p = 0.09] at 5 min between the two groups. Incidence of bradycardia [heart rate < 50 beats/mints.] was significantly higher in Group A as compared to Group B [p=0.038]. Conclusion: Intravenous bolus dose of phenylephrine 100 µg and ephedrine 6mg were both effective in treating hypotension after SA for elective cesarean section. Mean Apgar scores of the neonates at 1 and 5 min were comparable between the two groups. Key words: Spinal anesthesia, cesarean section, hypotension, ephedrine and phenylephrine Citation: Siddiqui AS, Salim B, Siddiqui SZ. Comparison of phenylephrine and ephedrine for treating hypotension after spinal anesthesia for cesarean section: A R and omized double-blind clinical trial. Anaesth Pain and Intensive Care 2015;19[1]:44-49