Amplification or duplication of chromosome band 21q22 with multiple copies of the AML1 gene and mutation of the TP53 gene in therapy-related MDS and AML.

Amplification or duplication of the AML1 gene at chromosome band 21q22 was detected by FISH using a locus-specific probe in three out of 171 unselected patients with therapy-related myelodysplasia (t-MDS) or t-AML (1.7%). In two patients AML1 signals were located tandemly on derivative chromosomes, in one patient on a dic(9;21) and in the the other patient on a derivative chromosome 18 made up of interchanging layers of material from chromosomes 9, 14, 18, and 21. In the third patient three single supernumerary copies of AML1 were located on derivatives of chromosomes 19 and 21. All three patients were older, had previously received therapy with alkylating agents without topoisomerase II inhibitors, had complex karyotypes including abnormalities of chromosomes 5 or 7, and presented acquired point mutations of the TP53 gene. No point mutations of the AML1 gene were observed. The results support a pivotal role of impaired TP53 function in the development of gene amplification or duplication in t-MDS and t-AML.     

Measurements of bone mineral density of the proximal femur by two commercially available dual energy X-ray absorptiometric systems.

Two dual energy X-ray absorptiometric (DXA) instruments have recently become commercially available for local bone densitometry: the QDR-1000 (Hologic Inc.) and the DPX (Lunar Radiation Corp.). We report the precision, influence of femoral rotation, correlation and agreement of bone mineral measurements of the proximal femur by these two instruments. In vitro (femur phantom) short-term precision was 1.1%-3.5%, and the long-term precision was 1.2%-3.8%. In vivo (groups of 10 premenopausal and 10 post-menopausal women) short-term precision of duplicate measurements was 1.6%-4.7%, and long-term precision was 1.9%-5.5%. Overall, the precision for Ward's triangle was over 3% and that for the femoral neck and trochanter, 2%-3%. Rotation of a femur phantom produced a statistically significant change in the bone mineral density (BMD) of the femoral neck. Within a clinically relevant range of femoral rotation (20 degrees inward rotation +/- 5 degrees) the coefficient of variation (CV%) increased by a mean factor of 1.1-1.4. Although the correlation (r less than 0.9) between BMD measurements of the proximal femur by the DPX and QDR-1000 in 30 postmenopausal women was high, there was lack of agreement between the two instruments. We found no statistically significant differences between the right and left femur in 30 postmenopausal women. A bilateral femur scan took a mean total time of about 22 min. We conclude that with the introduction of DXA instruments, the precision of bone mineral measurements of the proximal femur has improved. However, for comparability between commercially available DXA instruments, it might be advantageous if units were standardized.     

Systemic endotoxin and gastric mucosal pH are the best parameters to predict lethal outcome in a porcine model of abdominal sepsis according to multivariate analysis.

This study was devised to identify sepsis-relevant parameters that early and reliably predict a lethal outcome in intra-abdominal sepsis. In 18 Duroc pigs, peritonitis was induced through standardized gastrotomy. Twelve hours later the defect was oversewn and the abdominal cavity lavaged thoroughly. Sepsis relevant parameters were measured before initiating therapy, and 30 min later animals were extubated and observed for a period of 6 days under adequate analgesia with free access to water and food. All parameters were correlated with survival postoperatively. In the treatment group, 7 out of 18 pigs (39%) died within the observation period. Endotoxin level at 30 min after initiation of therapy [17.9 EU/mL (+/- 12.1) vs. 110.9 EU/mL (+/- 21); p <.001] and Delta pHi [0.015 (+/- 0.011) vs. -0.039 (+/- 0.013); p =.016] were identified as the two parameters with highest predictive power regarding mortality in a multivariate analysis. In conclusion measurement of endotoxin and gastric tonometry should gain wider clinical application in septic patients.     

Laparoscopic nephrectomy is cost effective compared with open nephrectomy in a large county hospital.

BACKGROUND AND OBJECTIVES: To evaluate the experience with laparoscopic nephrectomy in a large county hospital and perform a cost comparison between uncomplicated open and laparoscopic nephrectomy. METHODS: Eleven consecutive patients who underwent an uncomplicated laparoscopic nephrectomy in a large county hospital were compared with 8 patients who underwent uncomplicated open nephrectomy during the same period. Patient charts and corresponding billing records were reviewed to determine overall hospitalization cost and individual cost components. RESULTS: No perioperative complications occurred in either the laparoscopic or open group, and no statistically significant differences existed between groups with regard to patient demographics or operative parameters. The overall operating room costs favored the open nephrectomy group by dollars 1070 (P=0.003). However, the overall cost of hospitalization, surgeon professional fees, duration of hospitalization, room and board costs, laboratory, and radiology costs, pharmacy costs, intravenous solution and infusion pump costs all significantly favored the laparoscopic patient group. The mean difference in overall hospital cost between laparoscopic and open nephrectomy was dollars 1211 in favor of laparoscopy (P=0.037). CONCLUSIONS: Our experience with laparoscopic nephrectomy in a large county hospital demonstrates a clear economic advantage in favor of the laparoscopic approach. Given limited funding for public hospitals and a clear patient benefit, laparoscopic nephrectomy should constitute first-line therapy when nephrectomy is indicated.     

Changes in calcanean bone mineral occurring spontaneously and during hormone replacement therapy in early post-menopausal women.

The spontaneous calcanean bone loss occurring in healthy early post-menopausal women and the effect of two hormone replacement therapies (HRT's) were investigated in a longitudinal study. There was no difference between the right and left calcanean BMC or BMD (p > 0.15). The spontaneous bone loss was similar at all the skeletal sites measured, with a mean spontaneous loss in calcanean BMD of 1.6% over one year. Both HRT's significantly (p < 0.01) prevented the bone loss from all skeletal sites irrespective of the weight-bearing or content of trabecular bone, and (for the weight-bearing bones) there was even a gain in calcanean BMC and BMD and spinal BMD (p < 0.01). Bone mineral of the calcaneus and the spine correlated equally to body weight (r approximately 0.4, p < 0.001), whereas bone mineral in the forearm was not correlated to body weight. The correlations between the changes in bone mineral at the sites measured were all significant (r approximately 0.2-0.4).     

Diagnosis of scaphoid fractures:A prospective multicenter study of 1,052 patients with 160 fractures

In a prospective multicenter study of 1,052 patients with clinical signs of a scaphoid fracture, mammo-graphic films and fine intensifying screens were used at the radiographic examination. 5 standardized projections including 3 special projections focused on the scaphoid were taken. 150 fractures were diagnosed at the first examination but in 10 cases the fracture was first diagnosed at a second radiographic examination after 10-14 days.

The second examination still seems mandatory despite the use of high quality radiographs with optimal spatial resolution and contrast, and the value of supplementary special projections.     

Extended apical enlargement with hand files versus rotary NiTi files. Part II.

OBJECTIVE: The objective of this study was to compare 2 preparation techniques performed under simulated clinical conditions with extended apical enlargement following determination of the optimal apical preparation size (APS). STUDY DESIGN: After preflaring 240 root canals, APS was evaluated as outlined in Part I. The apical portion was shaped to APS either with rotary NiTi Lightspeed instruments (LS) or NiTi hand instruments (HA) using the balanced force technique in a phantom head. After sectioning the apical area at 3 levels, every cross section was analyzed microscopically for circumferential removal of canal wall dentine. Loss of working length, instrument separation, and perforation were additionally recorded. RESULTS: In 70% (LS) and 69% (HA) of the root canals, 2 of 3 levels demonstrated that the root canal dentin was cut circumferentially. Neither loss of working length nor perforation occurred in both groups. Four LS instruments separated. CONCLUSIONS: APS frequently results in a nearly complete apical preparation regardless of the preparation techniques. In a few cases apical enlargement to APS does not achieve complete cutting of the canal walls. There was a rather slight risk of serious procedural errors.     

A multicenter evaluation of safety of early extubation in liver transplant recipients.

Small single-institutional studies performed prior to the introduction of organ allocation using the Model for End-Stage Liver Disease (MELD) suggest that early airway extubation of liver transplant recipients is a safe practice. We designed a multicenter study to examine adverse events associated with early extubation in patients selected for liver transplantation using MELD score. A total of 7 institutions extubated all patients meeting study criteria and reported adverse events that occurred within 72 hours following surgery. Adverse events were uncommon: occurring in only 7.7% of 391 patients studied. Most adverse events were pulmonary or surgically related. Pulmonary complications were usually minor, requiring only an increase in ambient oxygen concentration. The majority of surgical adverse events required additional surgery. Analysis of a limited set of perioperative variables suggest that blood transfusions and technical factors were associated with an increased risk of adverse events. In conclusion, while early extubation appears to be safe under specified circumstances, there are performance differences between institutions that remain to be explained.