Hemodynamic characteristics of midazolam, propofol, and dexmedetomidine in healthy volunteers

Study Objective

To study the effect of intravenous (IV) sedation on blood pressure (BP), heart rate (HR), and respiratory rates (RR) to determine if IV sedatives differ with respect to their effect on BP, HR, and RR.

Design

Prospective, randomized, single-blinded, placebo-controlled study.

Setting

Monitored patient care room at a clinical research center.

Subjects

60 healthy ASA physical status 1 volunteers.

Interventions

Subjects were randomized to receive, in increasing doses, one of three IV sedatives: propofol, midazolam, or dexmedetomidine; or saline control.

Measurements

Blood pressure (systolic, diastolic), HR, and RR were recorded.

Main Results

A significant dose-dependent BP reduction occurred with dexmedetomidine and, to a lesser degree, with propofol; and there was good agreement of predicted versus measured drug concentrations for all sedatives. Blood pressure and HR of participants who received midazolam did not change.

Conclusions

When administered in sedative doses, dexmedetomidine and, to a lesser extent, midazolam, reduces BP in a dose-dependent fashion. Dexmedetomidine also reduces HR. Midazolam does not affect BP or HR.     

Intramural Metastatic Squamous Cell Carcinoma of Stomach

Intramural metastasis to the stomach (IMMS) from carcinoma esophagus, excluding direct invasion and spread to the stomach, is relatively uncommon. Diagnosis of IMMS is based on histological criteria, and it is associated with poor prognosis (Takubo et al. Cancer 65:1816–1819, 1990]. We report two patients of SCC oesophagus in whom intramural metastasis to stomach has occurred.     

Tamoxifen inhibits malignant peripheral nerve sheath tumor growth in an estrogen receptor-independent manner

Few therapeutic options are available for malignant peripheral nerve sheath tumors (MPNSTs), the most common malignancy associated with neurofibromatosis type 1 (NF1). Guided by clinical observations suggesting that some NF1-associated nerve sheath tumors are hormonally responsive, we hypothesized that the selective estrogen receptor (ER) modulator tamoxifen would inhibit MPNST tumorigenesis in vitro and in vivo. To test this hypothesis, we examined tamoxifen effects on MPNST cell proliferation and survival, MPNST xenograft growth, and the mechanism by which tamoxifen impeded these processes. We found that 1-5 μM 4-hydroxy-tamoxifen induced MPNST cell death, whereas 0.01-0.1 μM 4-hydroxy-tamoxifen inhibited mitogenesis. Dermal and plexiform neurofibromas, MPNSTs, and MPNST cell lines expressed ERβ and G-protein-coupled ER-1 (GPER); MPNSTs also expressed estrogen biosynthetic enzymes. However, MPNST cells did not secrete 17β-estradiol, exogenous 17β-estradiol did not stimulate mitogenesis or rescue 4-hydroxy-tamoxifen effects on MPNST cells, and the steroidal antiestrogen ICI-182,780 did not mimic tamoxifen effects on MPNST cells. Further, ablation of ERβ and GPER had no effect on MPNST proliferation, survival, or tamoxifen sensitivity, indicating that tamoxifen acts via an ER-independent mechanism. Consistent with this hypothesis, inhibitors of calmodulin (trifluoperazine, W-7), another known tamoxifen target, recapitulated 4-hydroxy-tamoxifen effects on MPNST cells. Tamoxifen was also effective in vivo, demonstrating potent antitumor activity in mice orthotopically xenografted with human MPNST cells. We conclude that 4-hydroxy-tamoxifen inhibits MPNST cell proliferation and survival via an ER-independent mechanism. The in vivo effectiveness of tamoxifen provides a rationale for clinical trials in cases of MPNSTs.     

Comparison of central corneal thickness measurements with the Galilei dual Scheimpflug analyzer and ultrasound pachymetry

Purpose:

To compare corneal pachymetry assessment by the Galilei dual Scheimpflug analyzer with that done by ultrasound (US) pachymetry.

Materials and Methods:

Forty six patients (92 eyes) were subjected to corneal pachymetry assessment by Galilei dual Scheimpflug analyzer and US. All the readings were taken by a single operator. Intraoperator repeatability for the Galilei was assessed by taking 10 readings in one eye each of 10 patients. To study the interoperator reproducibility for the Galilei, two observers took a single reading in both the eyes of 25 patients.

Results:

The mean central corneal thickness (CCT) measured by US was 541.83 ± 30.56 μm standard deviation (SD) and that measured by Galilei was 541.27 ± 30.07 μm (SD). There was no statistically significant difference between both the methods (P < 0.001). The coefficient of repeatability was 0.43% while the coefficient of reproducibility was 0.377% for the Galilei.

Conclusion:

Objective, noncontact measurement of the CCT with the Galilei dual Scheimpflug analyzer was convenient, had excellent intraoperator repeatability and interoperator reproducibility, and findings were similar to those obtained with standard US pachymetry.     

Massive osteolysis of hemimandible: a case report

Massive osteolysis or Gorham’s stout disease or phantom bone is a rare disorder which normally appears in adulthood with no specific predilection for any sex. Work to find out exact etiology of disorder has been done. But actual cause has not yet been found. Any of the bone could be involved in this disease. A clinical, radiographic and histological evaluation of massive osteolysis of mandible is presented and discussed.