Surgeon-initiated screening colonoscopy program based on SAGES and ASCRS recommendations in a general surgery practice

BACKGROUND

This study aimed to determine the utility of a screening colonoscopy program initiated by general surgeons in an academic center.

METHODS

New patients presenting to three general surgeons who met screening colonoscopy indications were asked whether they had undergone colorectal cancer (CRC) screening. The patients who had not undergone CRC screening were offered screening colonoscopies or referred to their gastroenterologists.

RESULTS

In the first 9-month period of the program, 200 patients who met the Society of American Gastrointestinal and Endoscopic Surgeons/American Society of Colon and Rectal Surgeons indications for CRC screening were asked whether they had undergone screenings. Only 46% (n = 92) reported any prior appropriate screenings. Of the patients who elected CRC screening by the surgeons, 55 underwent full colonoscopies (2 concurrently with hemorrhoidectomies), and 2 had flexible sigmoidoscopies. As a result of screening, 10 patients (18%) required treatment: 7 had polypectomies, 2 had partial colectomies, and 1 with an indication for surgery deferred treatment.

CONCLUSIONS

Most of the patients presenting to the general surgeon likely have not had CRC screening, and diligence in making appropriate recommendations should be routine. Colonoscopic findings requiring intervention are not insignificant.

MRI volumetric and intensity analysis of the cerebellum in Parkinson's disease patients infused with glial-derived neurotrophic factor (GDNF)

BACKGROUND

A recent human therapeutic trial using intraputaminal infusion of glial cell-derived neurotrophic factor (GDNF) in Parkinson's disease (PD) was abruptly terminated, partly due to safety concerns raised by the finding of cerebellar lesions in monkeys given high-dose GDNF.

METHODS

Magnetic resonance images from nine PD patients participating in this trial were analyzed to determine whether subtle volumetric or intensity changes could be detected in the cerebellum or elsewhere following GDNF treatment for over 1 year. Subtraction images were compared to a reference standard deviation map constructed by using identically-processed paired scans from 25 normal adults. In a separate voxel-based group morphometric (VBM) analysis of the same patient images, grey matter intensity was compared between pre and post-GDNF infusion scans using a repeated measures ANOVA with family-wise error threshold of P = 0.10. Two expert readers independently reviewed serial FLAIR images from all patients.

RESULTS

(1) There were no significant cerebellar differences in any of the nine individual PD patients (difference image analysis), (2) there were no significant morphometric differences between pre- and post-GDNF scans (VBM), and (3) there were no signal abnormalities in the cerebellum detected on the FLAIR images in PD patients (clinical scan review).

CONCLUSIONS

In concert with lack of evidence of cerebellar dysfunction on clinical examination, we find no imaging evidence of cerebellar injury in human subjects undergoing chronic intracerebral GDNF infusion.

Thin-layer ablation of human esophageal epithelium using a bipolar radiofrequency balloon device

BACKGROUND

The goal of this study was to determine the optimal treatment parameters for the ablation of human esophageal epithelium using a balloon-based bipolar radiofrequency (RF) energy electrode.

METHODS

Immediately prior to esophagectomy, subjects underwent esophagoscopy and ablation of two separate, 3-cm long, circumferential segments of non-tumor-bearing esophageal epithelium using a balloon-based bipolar RF energy electrode (BARRX Medical, Inc., Sunnyvale, CA, USA). Subjects were randomized to one of three energy density groups: 8, 10, or 12 J/cm2. RF energy was applied one time (1x) proximally and two times (2x) distally. Following resection, sections from each ablation zone were evaluated using H&E and diaphorase. Histological endpoints were complete epithelial ablation (yes/no), maximum ablation depth, and residual ablation thickness after tissue slough. Outcomes were compared according to energy density group and 1x vs 2x treatment.

RESULTS

Thirteen male subjects (age, 49-85 years) with esophageal adenocarcinoma underwent the ablation procedure followed by total esophagectomy. Complete epithelial removal occurred in the following zones: 10 J/cm2 (2x) and 12 J/cm2 (1x and 2x). The maximum depth of injury was the muscularis mucosae: 10 and 12 J/cm2 (both 2x). A second treatment (2x) did not significantly increase the depth of injury. Maximum thickness of residual ablation after tissue slough was only 35 microm.

CONCLUSIONS

Complete removal of the esophageal epithelium without injury to the submucosa or muscularis propria is possible using this balloon-based RF electrode at 10 J/cm2 (2x) or 12 J/cm2 (1x or 2x). A second application (2x) does not significantly increase ablation depth. These data have been used to select the appropriate settings for treating intestinal metaplasia in trials currently under way.

Longitudinal functional alterations in asymptomatic women at risk for Alzheimer's disease

PURPOSE

The authors sought to determine whether known alterations of brain function in normal individuals who are at high risk for Alzheimer's disease (AD) worsen or stay the same after a significant interval of time.

METHODS

The authors used functional magnetic resonance imaging (fMRI) to observe cortical activation during confrontation naming in 14 women with high AD risk and 10 with low risk, based on family history and apolipoprotein-E4 allele status. They repeated the identical scan protocol in the same patients after 4 years.

RESULTS

fMRI activation in high-AD-risk participants was found to be further diverged from that of their low-AD-risk counterparts over this period.

CONCLUSION

fMRI may report on the presence and progression of neuropathology in the ventral temporal cortex or in functionally connected regions in presymptomatic AD.

What happens to the rectus abdominus fascia after laparoscopic ventral hernia repair?

BACKGROUND

One criticism of laparoscopic ventral hernia repair (LVH) is that the rectus muscles are not re-approximated to the midline, and the effect of LVH repair on the fascial edges is unclear. Progressive migration of the fascial edges toward the midline has been observed anecdotally, but objective evidence remains limited. The purpose of this study is to observe the effect of LVH repair on the rectus abdominus fascia.

METHODS

Patients undergoing LVH repair with defects > 10 cm in horizontal diameter were identified prospectively and enrolled. All were repaired laparoscopically with intraperitoneal placement of mesh (DualMesh, W.L. Gore and Associates) using a standard approach. Radio-opaque clips were placed at the fascial edges intraoperatively to mark the defect, and plain abdominal films were taken postoperatively (Time 1) to establish the initial distance between clips (measured in cm). A subsequent follow-up film was taken (Time 2), and the difference in clip distance per patient was recorded. Results were analyzed using a chi-squared test.

RESULTS

Twelve patients qualified for analysis and their results were compared. Mean fascial defect size was 15.1 cm (range 8.3-22.0). With respect to change in clip distance from Times 1 to 2, three events were observed: (1) Diminished (i.e. medialized), (2) Enlarged, or (3) No Change. Ten patients (83%) medialized, one patient enlarged, and one patient showed no change (chi2 (d.f. = 2) 9.17, p < 0.0023).

CONCLUSIONS

Medialization of the rectus abdominus fascia occurs in the majority of patients undergoing LVH repair. Causes for this phenomenon are unclear: however eliminating intrabdominal pressure with intraperitoneal mesh placement likely plays a role.

Construct validation of the ProMIS simulator using a novel laparoscopic suturing task

BACKGROUND

The use of simulation for minimally invasive surgery (MIS) skills training has many advantages over current traditional methods. One advantage of simulation is that it enables an objective assessment of technical performance. The purpose of this study was to determine whether the ProMIS augmented reality simulator could objectively distinguish between levels of performance skills on a complex laparoscopic suturing task.

METHODS

Ten subjects--five laparoscopic experts and five laparoscopic novices--were assessed for baseline perceptual, visio-spatial, and psychomotor abilities using validated tests. After three trials of a novel laparoscopic suturing task were performed on the simulator, measures for time, smoothness of movement, and path distance were analyzed for each trial. Accuracy and errors were evaluated separately by two blinded reviewers to an interrater reliability of >0.8. Comparisons of mean performance measures were made between the two groups using a Mann-Whitney U test. Internal consistency of ProMIS measures was assessed with coefficient alpha.

RESULTS

The psychomotor performance of the experts was superior at baseline assessment (p < 0.001). On the laparoscopic suturing task, the experts performed significantly better than the novices across all three trials (p < 0.001). They performed the tasks between three and four times faster (p < 0.0001), had three times shorter instrument path length (p < 0.0001), and had four times greater smoothness of instrument movement (p < 0.009). Experts also showed greater consistency in their performance, as demonstrated by SDs across all measures, which were four times smaller than the novice group. Observed internal consistency of ProMIS measures was high (alpha = 0.95, p < 0.00001).

CONCLUSIONS

Preliminary results of construct validation efforts of the ProMIS simulator show that it can distinguish between experts and novices and has promising psychometric properties. The attractive feature of ProMIS is that a wide variety of MIS tasks can be used to train and assess technical skills.

Memories that last in old age: motor skill learning and memory preservation

Using an automated test panel, age-associated declines in learning, remembering and performing a novel visuomotor task were assessed in 497 normal adults ranging from 18 to 95 years old. As predicted, task performance times slowed with increasing age in the cross-sectional portion of the study. However in the subsequent longitudinal study, while motor learning was significantly slower in adults over 62 years old, motor memory was pristinely preserved in normal adults from 18 to 95 years old. When tested 2 years after the first training session and without intervening rehearsal, mean performance times were retained and continued to improve by 10% in young adults and 13% in aged adults, reflecting long lasting preservation of motor memories. While the maximum lifetime of an unpracticed, novel motor memory in humans is not known, the present study suggests that new motor memories can be retained for at least 2 years without rehearsal in normal aged adults. This age-resistant component of motor memory stands in contrast to the well-known decrements in other motor and cognitive processes with human aging.

Correlation between perceptual, visuo-spatial, and psychomotor aptitude to duration of training required to reach performance goals on the MIST-VR surgical simulator

Given the dynamic nature of modern surgical education, determining factors that may improve the efficiency of laparoscopic training is warranted. The objective of this study was to analyze whether perceptual, visuo-spatial, or psychomotor aptitude are related to the amount of training required to reach specific performance-based goals on a virtual reality surgical simulator. Sixteen MS4 medical students participated in an elective skills course intended to train laparoscopic skills. All were tested for perceptual, visuo-spatial, and psychomotor aptitude using previously validated psychological tests. Training involved as many instructor-guided 1-hour sessions as needed to reach performance goals on a custom designed MIST-VR manipulation-diathermy task (Mentice AB, Gothenberg, Sweden). Thirteen subjects reached performance goals by the end of the course. Two were excluded from analysis due to previous experience with the MIST-VR (total n = 11). Perceptual ability (r = -0.76, P = 0.007) and psychomotor skills (r = 0.62, P = 0.04) significantly correlated with the number of trials required. Visuo-spatial ability did not significantly correlate with training duration. The number of trials required to train subjects to performance goals on the MIST-VR manipulation diathermy task is significantly related to perceptual and psychomotor aptitude.

Laparoscopic palliative surgery for complicated colorectal cancer

BACKGROUND

The aim of this study was to evaluate the feasibility and outcomes of the laparoscopic approach for the palliation of advanced complicated colorectal cancer (CRC).

METHODS

We reviewed 21 laparoscopic palliative procedures for emergent complications of advanced CRC between 1994 and 2002. Intraoperative complications, estimated blood loss, transfusions, operative times, time to first bowel movement, length of hospital stay, and postoperative complications were assessed.

RESULTS

Indications for surgery included perforation (n = 10), bleeding (n = 7), and obstruction (n = 4). A proximal diverting procedure was performed in all patients, and a concomitant colon resection was performed in 18 patients (86%). The mean operative time was 181 +/- 22 min. Estimated blood loss was 283 +/- 48 cc, with three patients (14%) requiring transfusions. The average length of hospital stay was 8.6 +/- 2 days, and time to first bowel movement was 61 +/- 9 h. The complication rate and the 30-day mortality rate were 33% and 0%, respectively.

CONCLUSION

A laparoscopic approach to address advanced CRC is safe and effective and should be considered part of the surgeon's armamentarium for the palliation of advanced complicated CRC.

The early identification of dyslexia: children with English as an additional language

It is generally accepted that dyslexia should be identified early for interventions to have maximum effect. However, when children speak English as an additional language (EAL), diagnosis is more complex and there is concern that these children tend to be under-identified. This paper reports a longitudinal study following the development of phonological awareness skills in relation to progress in learning to read with a cohort of British Asian children learning EAL and their monolingual peers. It also sought to determine the usefulness of a measure of phonological skills for the identification of dyslexic-type difficulties in children learning EAL. Analysis revealed that both cohorts achieved similar levels of reading accuracy in school Years 2, 4 and 6, with higher levels of reading comprehension for the monolingual children and faster reading fluency for children learning EAL in each school year. There was a similar pattern of relationships between the reading measures and measures of phonological awareness for both groups of children. However, monolingual children achieved higher levels of rhyme detection and alliteration fluency whilst the children learning EAL achieved faster number naming times. Overall, a phonological assessment battery was useful in identifying reading accuracy related difficulties in both groups of children. However, concerns are raised about the sensitivity of such measures following the introduction of the Literacy Hour.

Optimal management of the morbidly obese patient SAGES appropriateness conference statement

BACKGROUND

Obesity is a growing health problem that contributes to numerous life-threatening or disabling disorders, including coronary artery disease, hypertension, type 2 diabetes mellitus, hyperlipidemia, degenerative joint disease, and obstructive sleep apnea. Significant weight reduction in the morbidly obese improves or reverses associated illness and benefits well-being. The purpose of the SAGES Appropriateness Conference was to summarize the state of the art for open and laparoscopic operations for the morbidly obese.

METHODS

The English literature comparing bariatric procedures was reviewed and grouped by level of evidence by three surgeons (BS, LV, and CC). From more than 1,500 articles, all conference participants were provided with reprints and table summaries of no less than 50 selected manuscripts. Ten experts were requested to present reviews and make evidence-based arguments for and against the open and laparoscopic approaches in written format. An expert panel of six surgeons, including an ethicist and patient, commented on implications of data presented. The finalized statement was e-mailed to all participants for approval and comment.

RESULTS

Consensus statements were achieved on various aspects of morbid obesity, including indications for surgery, resolution of comorbid illnesses with significant weight loss, and the importance of committed bariatric program. Our panel of experts agreed, in general, to the advantages of laparoscopic approaches compared to open operations in skilled hands.

CONCLUSIONS

Laparoscopic Roux-en-Y gastric bypass (RYGB) affords improved short-term recovery compared to open gastric bypass. Laparoscopic adjustable banding can be performed with lower average mortality than either RYGB or any of the malabsorptive operations, and it produces variable degrees of short-term weight loss. Prospective randomized trials are needed to compare gastric bypass, malabsorptive, and restrictive procedures.

Discriminative validity of the Minimally Invasive Surgical Trainer in Virtual Reality (MIST-VR) using criteria levels based on expert performance

BACKGROUND

Increasing constraints on the time and resources needed to train surgeons have led to a new emphasis on finding innovative ways to teach surgical skills outside the operating room. Virtual reality training has been proposed as a method to both instruct surgical students and evaluate the psychomotor components of minimally invasive surgery ex vivo.

METHODS

The performance of 100 laparoscopic novices was compared to that of 12 experienced (>50 minimally invasive procedures) and 12 inexperienced (<10 minimally invasive procedures) laparoscopic surgeons. The values of the experienced surgeons' performance were used as benchmark comparators (or criterion measures). Each subject completed six tasks on the Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR) three times. The outcome measures were time to complete the task, number of errors, economy of instrument movement, and economy of diathermy.

RESULTS

After three trials, the mean performance of the medical students approached that of the experienced surgeons. However, 7-27% of the scores of the students fell more than two SD below the mean scores of the experienced surgeons (the criterion level).

CONCLUSIONS

The MIST-VR system is capable of evaluating the psychomotor skills necessary in laparoscopic surgery and discriminating between experts and novices. Furthermore, although some novices improved their skills quickly, a subset had difficulty acquiring the psychomotor skills. The MIST-VR may be useful in identifying that subset of novices.

Laparoscopic vs open resection for the treatment of diverticular disease

INTRODUCTION

The aim of this study was to evaluate whether laparoscopic colon resection (LCR) offers any advantages over open colon resection (OCR) in the treatment of diverticular disease.

METHODS

Between 1992 and 2002, 95 patients underwent LCR and 80 patients underwent OCR for the treatment of diverticular disease. Demographics, details of operative procedure, outcome, and pathology were compared.

RESULTS

Patients in both groups were matched for age, sex, body mass index, history of previous abdominal operations, comorbidities, location of the disease, and presence of complications. LCR resulted in significantly less estimated blood loss and postoperative complications, shorter time to first bowel movement, and shorter length of stay than the OCR. There was no difference in operative time, intraoperative complications, mortality rates between groups.

CONCLUSIONS

LCR is a safe and effective approach for the treatment of patients with diverticular disease. It results in less estimated blood loss, shorter time to first bowel movement, less postoperative complications, and shorter length of hospital stay.

Comparative results of endoluminal gastroplasty and laparoscopic antireflux surgery for the treatment of GERD

BACKGROUND

Transoral endoluminal gastroplasty (EG) by the Bard Endocinch device is available for the treatment of gastroesophageal reflux disease (GERD). This study assessed the early (<or=12 months) outcomes in patients undergoing EG performed by one gastroenterologist compared with another set of patients referred by the same gastroenterologist for laparoscopic antireflux surgery (LAS) at a foregut surgery center.

METHODS

From June 2000 to July 2002, 87 consecutive patients cared for by a single gastroenterologist were diagnosed with refractory GERD and underwent either EG (n = 47) or referral for LAS (n = 40). Preoperative evaluation included symptom assessment, pH studies, and motility studies. Outcomes were assessed by symptomatic improvement and dependence on anti-acid medications. Data analyzed by chi-square or Mann-Whitney tests are reported as mean +/- SEM.

RESULTS

Preoperative symptom duration, Johnson-DeMeester (JD) score, % time pH < 4, and reflux episodes were statistically similar in both treatment groups. The follow-up times for EG and LAS groups were 7.3 +/- 0.9 and 8 +/- 0.4 months, respectively. Of EG patients, 94% were available for follow-up, and all LAS patients had follow-up data. Overall, 66% of patients were satisfied with EG as compared to 93% after LAS (p = 0.1). Postoperative PPI/motility agent use was 32% for EG and 13% for LAS (p = 0.03). Identifiable causes of EG failure were premature procedure termination due to hypoxia or bleeding (three patients), intractable vomiting (two patients), and delayed gastric emptying (five patients). Three EG patients subsequently had LAS within 6 months of the procedure.

CONCLUSIONS

LAS offers greater reduction in medication use than EG, as well as more durable patient satisfaction. Benefits of EG may include short-term symptomatic improvement while considering definitive surgical management.

Preoperative factors predictive of complicated postoperative management after Roux-en-Y gastric bypass for morbid obesity

INTRODUCTION

This study was undertaken to determine preoperative predictive factors of complicated postoperative management after Roux-en-Y gastric bypass (RYGB) for morbid obesity.

METHODS

Between January 1999 and January 2002, 158 patients who underwent a RYGB received a standardized preoperative evaluation and data were collected prospectively. Complicated postoperative management was defined as patients requiring postoperative ICU admission for > or =48 h, or those needing transfer from the floor to the ICU. Patients with complicated management were compared with those in whom ICU admission was not necessary.

RESULTS

Twenty-three patients (14.5%) required prolonged ICU admission (mean stay of 6.3 +/- 1.7 days). After multivariate analysis, body mass index (BMI) >50 kg/m2, forced expiratory volume (FEV1) <80% predicted, previous abdominal surgeries, and abnormal EKG were found to be independently associated with an increased likelihood of complicated postoperative care.

CONCLUSION

BMI >50 kg/m2, FEV1 <80% predicted, previous abdominal surgeries, and abnormal EKG increase the likelihood of complicated postoperative management after RYGB for morbid obesity.

Can current technology be integrated to facilitate laparoscopic living donor hepatectomy?

BACKGROUND

Living donor hepatectomy (LDH) is a technically demanding procedure that is an alternative for providing livers for transplantation. Unlike liver resections for other pathology, LDH requires preservation of the major vessels and biliary tree. This study was performed to determine if current technology can be integrated to perform laparoscopic LDH.

METHODS

Six adult sheep underwent laparoscopic LDH of the left lateral segment under general anesthesia. Instruments utilized included standard dissecting instruments, ultrasound, ultrasonic dissectors, CUSA, the TissueLink Floating Ball, and endoscopic staplers.

RESULTS

LDH-harvested liver grafts were 44% of whole liver weight. Estimated blood loss was 300 cc. Warm ischemia time was 5-7 min. Grafts were delivered through 18-cm abdominal wounds. Major vessels and biliary anatomy were positively identified in the grafts.

CONCLUSIONS

Laparoscopic LDH can be performed with available technology. Theoretical advantages include reduced liver manipulation and smaller wound size.

Survival of bacterial isolates exposed to simulated Jovian trapped radiation belt electrons and solar wind protons

With missions to Jupiter, the spacecraft will be exposed for extended durations to solar wind radiation and the Jovian trapped radiation belt. This study is designed to determine the effect of these radiation environments on spacecraft bacterial isolates. The information can be used in the probability of contamination analysis for these missions. A bacterial subpopulation from Mariner Mars 1971 spacecraft (nine spore-forming and three non-spore-forming isolates) plus two comparative organisms, Staphylococcus epidermidis ATCC 17917 and a strain of Bacillus subtilis var. niger, were exposed to 2, 12, and 25 MeV electrons at different doses with simultaneous exposure to a vacuum of 1.3 x 10(-4) N m-2 at 20 and -20 degrees C. The radioresistance of the subpopulation was dependent on the isolate, dose and energy of electrons. Temperature affected the radioresistance of only the spore-forming isolates. Survival data indicated that spores were reduced approximately 1 log/1500 J kg-1 (10 J kg-1=1 krad), while non-spore-forming isolates (micrococci) were reduced 1.5-2 logs/1500 J kg-1 with the exception of an apparent radioresistant isolate whose resistance approached that of the spores. The subpopulation was found to be less resistant to lower energy than to higher energy electrons. The bacterial isolates were exposed to 3 keV protons under the same conditions as the electrons with a total fluence of 1.5 x 10(13) p cm-2 and a dose rate of 8.6 x 10(9) p cm-2 s-1. The results showed that only 20% of S. epidermidis and 45% of B. subtilis populations survived exposure to the 3 keV protons, while the mean survival of the spacecraft subpopulation was 45% with a range from 31.8% (non-spore-former) to 64.8% (non-spore-former). No significant difference existed between spore-forming and non-spore-forming isolates.

Telomeric protein distributions and remodeling through the cell cycle in Saccharomyces cerevisiae

In Saccharomyces cerevisiae, telomeric DNA is protected by a nonnucleosomal protein complex, tethered by the protein Rap1. Rif and Sir proteins, which interact with Rap1p, are thought to have further interactions with conventional nucleosomic chromatin to create a repressive structure that protects the chromosome end. We showed by microarray analysis that Rif1p association with the chromosome ends extends to subtelomeric regions many kilobases internal to the terminal telomeric repeats and correlates strongly with the previously determined genomic footprints of Rap1p and the Sir2-4 proteins in these regions. Although the end-protection function of telomeres is essential for genomic stability, telomeric DNA must also be copied by the conventional DNA replication machinery and replenished by telomerase, suggesting that transient remodeling of the telomeric chromatin might result in distinct protein complexes at different stages of the cell cycle. Using chromatin immunoprecipitation, we monitored the association of Rap1p, Rif1p, Rif2p, and the protein component of telomerase, Est2p, with telomeric DNA through the cell cycle. We provide evidence for dynamic remodeling of these components at telomeres.

Hippocampal volume as an index of Alzheimer neuropathology: findings from the Nun Study

OBJECTIVE

To determine whether hippocampal volume is a sensitive and specific indicator of Alzheimer neuropathology, regardless of the presence or absence of cognitive and memory impairment.

METHODS

Postmortem MRI scans were obtained for the first 56 participants of the Nun Study who were scanned. The area under receiver operating characteristic curves, sensitivity, specificity, and positive and negative predictive values were used to assess the diagnostic accuracy of hippocampal volume in predicting fulfillment of Alzheimer neuropathologic criteria and differences in Braak staging.

RESULTS

Hippocampal volume predicted fulfillment of neuropathologic criteria for AD for all 56 participants (p < 0.001): 24 sisters who were demented (p = 0.036); 32 sisters who remained nondemented (p < 0.001), 8 sisters who remained nondemented but had memory impairment (p < 0.001), and 24 sisters who were intact with regard to memory and cognition at the final examination prior to death (p = 0.003). In individuals who remained nondemented, hippocampal volume was a better indicator of AD neuropathology than a delayed memory measure. Among nondemented sisters, Braak stages III and VI were distinguishable from Braak stages II or lower (p = 0.001). Among cognitively intact individuals, those in Braak stage II could be distinguished from those in stage I or less (p = 0.025).

CONCLUSION

Volumetric measures of the hippocampus may be useful in identifying nondemented individuals who satisfy neuropathologic criteria for AD as well as pathologic stages of AD that may be present decades before initial clinical expression.

Long-term outcome of laparoscopic repair of paraesophageal hernia

BACKGROUND

It has been reported that the laparoscopic repair of paraesophageal hernias is associated with higher complication and recurrence rates than the open methods of repair.

METHODS

We identified 136 consecutive patients who underwent laparoscopic repair of a paraesophageal hernia between 1993 and 1999. Patient demographics and symptom scores for regurgitation, heartburn, chest pain, and dysphagia at presentation and at last follow-up were recorded (0 = none, 1 = mild, 2 = moderate, 3 = severe). The operative records were reviewed, and early and late complications were noted. Only patients with a follow-up of >1 were included in the analysis.

RESULTS

The median age was 64 years, and there was a female preponderance (1.8:1). Most patients had some medical comorbidity; the American Society of Anesthesiologists (ASA) scores were <2 in eight patients and ?2 in 117 patients. Three laparoscopic operations were converted to open procedures. There were nine intraoperative complications, five early complications, and three related deaths (morbidity and mortality rates of 10.2% and 2.2%, respectively). Follow-up data were available for 83 patients (66%), and the mean follow-up time was 40 months (range, 12-82). The percentage of patients experiencing chest pain, dysphagia, heartburn, and regurgitation in the moderate to severe range dropped from a range of 34-47% to 5-7% (p <0.05). Three patients underwent repeat laparoscopic repair for symptomatic recurrence.

CONCLUSION

The laparoscopic repair of paraesophageal hernias provides excellent long-term symptomatic relief in the majority of patients and has a low rate of symptomatic recurrence. The complication and death rates may be related in part to the higher incidence of comorbidities in this somewhat elderly patient population.

Frequency of postoperative nausea and vomiting in patients undergoing laparoscopic foregut surgery

BACKGROUND

Wrap disruption or intrathoracic herniation of a fundoplication is a dreaded complication of laparoscopic foregut surgery. This problem may often be related to postoperative nausea and vomiting (PONV). This study aimed to investigate the occurrence of PONV and its management in patients undergoing laparoscopic foregut procedures.

METHODS

Between January 31 and May 23, 2000, 104 patients undergoing laparoscopic foregut procedures (fundoplication, myotomy, or paraesophageal hernia repair) were followed prospectively. Their postoperative course was documented along with the occurrence and management of PONV. All laparoscopic foregut surgery patients are managed postoperatively with a uniform clinical pathway, and their care is focused on a nursing unit with skill and experience in postoperative management.

RESULTS

Nausea was documented in the postanesthesia care unit (PACU) for 30.1% of the patients, and for 59.6% of the patients during their nursing unit stay. Antiemetics were given to all the patients with documented nausea. Emesis was noted in 1.9% of the patients in the PACU, as compared with 3.8% of the patients on the floor. In one of the patients with nursing unit emesis, an acute wrap herniation into the chest occurred, necessitating a return to the operating room for correction. The patients with a history of postoperative nausea did not have a higher rate of PONV than in those with no history of postoperative nausea. The use of preoperative or intraoperative antiemetics did not appear to alter the occurrence of PONV. Postoperative nausea occurred in 60% of the patients administered preoperative antiemetic, as compared with 64% of the patients who received no preoperative antiemetic. The average length of hospital stay was longer in those with PONV than in those with no PONV (2.6 vs 1.8 days).

CONCLUSION

Nausea after laparoscopic foregut procedures is common, occurring twice as often on the nursing unit as in the PACU. The occurrence of PONV leads to a longer hospital stay, and can result in significant sequelae requiring reoperation. The use of preoperative or intraoperative antiemetics does not alter the frequency of postoperative nausea, suggesting the need to develop effective preemptive regimens for patients undergoing laparoscopic foregut procedures. The high rate of PONV and its potential risk of damage to a fundoplication and hiatal hernia repair should lead surgeons to consider whether laparoscopic foregut procedures should ever be performed on an outpatient basis.

Women at risk for AD show increased parietal activation during a fluency task

BACKGROUND

Imaging studies have shown disparities in resting metabolism and in functional activation between cognitively normal individuals at high and low risk for AD. A recent study has shown increased parietal activation in high-risk subjects during a paired associates recall task, which the authors postulated might overlap activation typically observed in verbal fluency.

OBJECTIVE

To determine whether parietal activation is altered in a letter fluency task in cognitively normal individuals at high risk for AD.

METHODS

fMRI was used to compare cortical activation between two groups of cognitively normal women differing in their risk for developing AD. A letter fluency task was used, which activates left frontal and parietal regions. The risk groups differed in family history of AD and APOE allele status but were matched in age, education, and measures of cognitive performance. Average age of the study participants was 53 years.

RESULTS

The regional patterns of brain activation were similar between groups and similar to patterns observed by other investigators. However, the high-risk group showed significantly increased activation in the left parietal region despite identical letter fluency performance between risk groups.

CONCLUSIONS

Cognitively normal individuals at high risk for AD show increased brain activation in the left parietal region with letter fluency, a region adjacent to that observed by others using a recall task. This convergence of results indicates disruption of functional circuits involving the left parietal lobe in asymptomatic individuals at increased risk for AD.

Success factors and hurdles in quality improvement in a children's hospital

A set of nurse/respiratory therapist-driven algorithms developed by a multidisciplinary team with the goal of "liberating" mechanically ventilated pediatric patients more rapidly from the ventilator resulted in sustained improvement over a 47-month period. The difference between expected and observed billed ventilator hour totals was over 22,000 hours (475 hours per month), a 17.5% reduction, which was significant at the P =.03 level by multiple linear regression analysis. Length of stay and mortality rate were unchanged. This difference represents a measure of the unrecognized cost of a nonstandardized approach to the weaning process. This reports reviews this team's success factors and hurdles and offers practical suggestions for pediatric surgeons interested in leading quality improvement initiatives.

Indoloquinoxaline compounds that selectively antagonize P-glycoprotein

Tumor cells often develop drug resistance through overexpression of membrane transport proteins that effectively efflux anticancer agents. The pharmacologies of the two best-studied transporters, P-glycoprotein (Pgp) and MRP1, are partially overlapping but distinct. To improve the therapeutic potential of drug resistance reversing agents, we have developed a program to identify compounds with selectivity for Pgp or MRP1. Screening of a commercial library of compounds identified indoloquinoxaline compounds with transporter selectivity, and certain examples were synthesized and further evaluated. 1,4-Dibutoxy-6H-indolo[2,3-b]quinoxaline and 4,7-dibutoxy-2,3-dihydrobenzimidazole-2-spiro-3-indolin-2-one were synthesized by condensation of 3,6-dibutoxy-1,4-diaminobenzene and isatin. Neither compound was cytotoxic to MCF-7 cells, nor did either one affect the sensitivity of MCF-7/VP or HL-60/ADR cells at doses up to at least 20 microM, indicating that they do not antagonize MRP1. In contrast, each compound, at doses as low as 0.25 microM, sensitized NCI/ADR cells to vinblastine, actinomycin D, Taxol, and doxorubicin, indicating that they effectively reverse Pgp-mediated multidrug resistance (MDR). Furthermore, the compounds sensitized two additional cell lines that overexpress Pgp to this panel of anticancer drugs. However, these compounds did not affect the sensitivities of MCF-7 or T24 cells to these cytotoxic drugs, and did not alter the sensitivities of any of the tested cell lines to cisplatin or 5-fluorouracil. Both compounds enhanced the intracellular accumulation of [3H]vinblastine by NCI/ADR cells, but did not inhibit photoaffinity labeling of Pgp by [3H]azidopine at concentrations up to at least 100 microM. Therefore, these novel nontoxic indoloquinoxalines selectively sensitize Pgp-overexpressing cells to drugs that are subject to transport by this protein, without modulating the sensitivities of MRP1-overexpressing or non-Pgp cells to cytotoxic drugs. Because of this transporter selectivity, we predict that these compounds will be effective MDR modulators in vivo.

An integrated computational pipeline and database to support whole-genome sequence annotation

We describe here our experience in annotating the Drosophila melanogaster genome sequence, in the course of which we developed several new open-source software tools and a database schema to support large-scale genome annotation. We have developed these into an integrated and reusable software system for whole-genome annotation. The key contributions to overall annotation quality are the marshalling of high-quality sequences for alignments and the design of a system with an adaptable and expandable flexible architecture.

Are the favorable outcomes of splenectomy predictable inpatients with idiopathic thrombocytopenic purpura (ITP)?

BACKGROUND

Historically, splenectomy has been an accepted procedure in the management of immune thrombocytopenic purpura (ITP). However, it is also true that the response to splenectomy in patients with ITP seems to be unpredictable. Therefore, the purpose of this study was to identify clinical variables that might predict a favorable response to splenectomy in patients with ITP.

METHODS

Data were collected retrospectively for 40 adult patients with ITP who underwent laparoscopic (LS) and open (OS) splenectomy at Emory University Hospital between 1992 and 1999. Demographics and outcomes were recorded. Age, sex, disease duration, comorbidities (ASA > 2), previous response to steroids and/or other medications, and preoperative platelet count were analyzed by univariate (t-test, Fisher's exact test) and multivariate statistical methods.

RESULTS

Of the 20 patients in each group, improved platelet counts were noted in 18 patients (90%) in the LS group and 20 patients (100%) in the OS group. Follow-up (16 +/- 3 months) was obtained in 19 LS patients (95%) and 16 OS patients (80%), with 84% and 87.5% sustained response rates, respectively. After univariate analysis, two variables (age and disease duration) were found to be significantly related to the outcome of splenectomy (p <lt; 0.01). However, after multiple logistic regression analysis, only disease duration (relative risk = 1.083; CI, 1.004-1.167) was an independent prognostic factor for a sustained response to splenectomy.

CONCLUSION

These results suggest that the response to splenectomy (laparoscopic and open) in patients with ITP cannot be adequately predicted on the basis of presplenectomy clinical variables. However, disease duration and patient age should be taken into consideration when selecting patients for splenectomy.

Response of atypical symptoms of gastro-oesophageal reflux to antireflux surgery

BACKGROUND

Atypical manifestations of gastro-oesophageal reflux (GOR) include asthma, chest pain, cough and hoarseness. The effectiveness of antireflux surgery for these symptoms is uncertain. The present study compared symptomatic response rates for typical and atypical GOR symptoms after fundoplication.

METHODS

Between October 1991 and January 1998, 324 patients underwent laparoscopic fundoplication at Emory University Hospital and returned postoperative questionnaires. Severity of typical (heartburn) and atypical (asthma, chest pain, cough and hoarseness) GOR symptoms was reported by patients on a 0-4 scale before surgery, and at 6 and 52 weeks after operation. Patients were stratified based on preoperative symptoms into three groups: group 1 (severe heartburn/minimal atypical symptoms), group 2 (severe heartburn/severe atypical symptoms) and group 3 (minimal heartburn/severe atypical symptoms).

RESULTS

In group 1 (n = 173) heartburn improved in 99 per cent and resolved in 87 per cent. In group 2 (n = 95) heartburn improved in 95 per cent and resolved in 76 per cent, and atypical symptoms improved in 94 per cent and resolved in 42 per cent. In group 3 (n = 56) atypical symptoms improved in 93 per cent and resolved in 48 per cent. Although all symptoms were improved by fundoplication, resolution was more likely for heartburn than for atypical symptoms.

CONCLUSION

Atypical symptoms of GOR are improved by fundoplication, but symptom resolution occurs in fewer than 50 per cent of patients.

Effects of a weaning protocol on ventilated pediatric intensive care unit (PICU) patients

As part of a learning collaborative sponsored by the Center for the Evaluative Clinical Sciences (CECS) at Dartmouth College, a multidisciplinary pediatric intensive care unit (PICU) group began meeting in 1997 to evaluate potential performance improvement (PI) opportunities. A reduction in mechanical ventilation (MV) hours was the initial team focus. The multidisciplinary team developed and implemented protocols and physician order sets outlining care for MV weaning, neuromuscular blockade/therapeutic paralyzation, and enteral feedings. Since the initiation of our protocols in July 1997, we have significantly reduced the number of hours our PICU patients receive MV.

The effect of low dose methotrexate on bone density

OBJECTIVE

High dose methotrexate (MTX) has been linked with bone loss in oncology patients. However, it is unclear whether longterm low dose MTX used in the treatment of inflammatory arthritis is associated with bone loss. We compared the effect of low dose MTX on bone density in prospectively recruited patients with rheumatoid arthritis (RA) and psoriasis/psoriatic arthritis (Ps/PsA).

METHODS

Thirty RA patients and 30 Ps/PsA patients taking MTX were compared to controls not taking MTX (30 with RA, 27 Ps/PsA). Bone mineral density (BMD) of the radius, lumbar spine, trochanter, and femoral neck was measured using Lunar dual energy x-ray absorptiometry. Student t tests were used to detect differences in bone density (using Z scores) of the MTX group versus controls for both the RA and Ps/PsA groups. Analysis of covariance was used to examine for confounders including disease duration, disease activity, age, and sex.

RESULTS

BMD of the radius/femoral neck/trochanter did not differ significantly between the MTX treated groups and controls when analyzed by Z scores. The mean difference between the MTX group and controls of the femoral neck was 0.040 (95% CI -0.40, 0.12) and 0.060 (95% CI -0.30, 0.15) for the RA and Ps/PsA groups, respectively. The absolute BMD of the lumbar spine (L2-L4) was higher in the RA MTX group than in controls. Analysis of covariance did not reveal an effect of study group on bone density.

CONCLUSION

This study suggests that low dose MTX does not have a negative effect on bone density, at either cortical or trabecular sites.

Cellular pharmacology of cerulenin analogs that inhibit protein palmitoylation

S-palmitoylation is a dynamic post-translational modification of certain proteins, which helps determine membrane association and may function to enhance the interactions of signaling molecules with their activated receptors and effector systems. Unlike enzymes that catalyze other protein lipidation reactions, e.g. farnesylation and N-myristoylation, protein palmitoyltransferase is virtually uncharacterized biochemically. We have described previously the synthesis of cerulenin analogs including cis-2,3-epoxy-4-oxononadecanamide (16C) and cis-2,3-epoxy-4-oxododecanamide (9C) that inhibit protein palmitoylation (Lawrence et al., J Med Chem 1999;42:4932-41), most likely through covalent alkylation of protein palmitoyltransferase. [3H]9C and [3H]16C were prepared by catalytic incorporation of 3H2 into unsaturated precursors for further study of their cellular pharmacology. After 4 hr, T24 bladder carcinoma cells in the absence of serum accumulated a 4-fold higher intracellular level of [3H]16C than of [3H]9C. Uptake of [3H]9C and [3H]16C was reduced by the presence of serum in the medium, suggesting their binding to serum proteins. [3H]9C and [3H]16C alkylated unique patterns of proteins in T24 cells, with proteins of approximately 80 and 31 kDa being labeled by each compound. A panel of human tumor cell lines demonstrated half-maximal proliferation inhibition at concentrations of 7-30, 4-16, and 8-36 microM, for cerulenin, 9C, and 16C, respectively, indicating that the cell lines have approximately equal sensitivity to these compounds. Different cell lines have similar patterns of protein alkylation by [3H]9C or [3H]16C, with labeling intensity related to cytotoxicity of the compounds. Since both 9C and 16C inhibit palmitoylation, the commonly labeled proteins are candidates for human protein palmitoyltransferase.

A computer-based laparoscopic skills assessment device differentiates experienced from novice laparoscopic surgeons

BACKGROUND

The acquisition of laparoscopic skills is difficult to assess. Previously, through the use of a computer-based skills assessment device (SAD), we have shown that assessments of the time needed to perform a task and graded observations of task performance overestimate the speed at which laparoscopic skills can be acquired. The aim of this study was to test the ability of a laparoscopic SAD to differentiate novices from experienced laparoscopic surgeons and thereby further validate its use in surgical education.

METHODS

Using a laparoscopic simulator platform integrated with task simulation and data collection software (MIST VR), we tested both experienced and novice laparoscopists. Each group performed three tasks with a minimum of seven repetitions. The tasks consisted of target acquisition, target traversal, and target manipulation with diathermy. Within each task, time (T), errors (E), and economy of movement for each hand (EML, EMR) were assessed. Results were reported as mean +/- SEM, and comparisons were made using an independent samples t-test.

RESULTS

For the target acquisition task, the expert group performed the task faster than the novice group (5.5 +/- 0.24 vs 7.6 +/- 0.40 sec, p < 0.05); the experts also made fewer errors (0.5 +/- 0.10 vs 0.8 +/- 0.11 errors, p < 0.05), and achieved both a better EML (1.8 +/- 0.6 vs 2.3 +/- 0.9, p < 0.05) and a better EMR (2.0 +/- 0.1 vs 2.9 +/- 0.21, p < 0.05). In the target traversal task, the experts made fewer errors than the novices (2.2 +/- 0.25 vs 4.6 +/- 0.38 errors, p < 0.05). For the manipulation and diathermy tasks, the expert group completed the task faster (30.8 +/- 1.5 vs 39 +/- 1.5 sec, p < 0.05), made fewer errors (5.3 +/- 0.59 vs 8.1 +/- 0.63 errors, p < 0.05), and had a better EML (6.0 +/- 0.37 vs 7.2 +/- 0.45, p < 0.05) and EMR (4.3 +/- 0.23 vs 5.8 +/- 0.36, p < 0.05) than the novices.

CONCLUSION

A laparoscopic skills assessment device can discern levels of laparoscopic manipulative skill. This type of device can be used in surgical training to make objective assessments of the acquisition of laparoscopic skills.

Bile duct injury during laparoscopic cholecystectomy: results of a national survey

OBJECTIVE

To determine whether surgical residency training has influenced the occurrence of common bile duct injuries during laparoscopic cholecystectomy, and to asses the anatomic and technical details of bile duct injuries from the practices of surgeons trained in laparoscopic cholecystectomy after residency versus surgeons trained in laparoscopic cholecystectomy during residency.

SUMMARY BACKGROUND DATA

Shortly after the introduction of laparoscopic cholecystectomy, the rate of injury to the common bile duct increased to 0.5%, and injuries were more commonly reported early in each surgeon's experience. It is not known whether learning laparoscopic cholecystectomy during surgery residency influences this pattern.

METHODS

An anonymous questionnaire was mailed to 3,657 surgeons across the United States who completed an Accreditation Council for Graduate Medical Education (ACGME)-approved residency between 1980 and 1990 (group A) or 1992 and 1998 (group B). All surgeons in group A learned laparoscopic cholecystectomy after residency, and all those in group B learned laparoscopic cholecystectomy during residency. Information obtained included practice description, number of laparoscopic cholecystectomies completed since residency, postgraduate training in laparoscopy, and annual volume of laparoscopic cholecystectomy in the surgeon's hospital. In addition, technical details queried included the completion of a cholangiogram, the interval between injury and identification, the method of repair, and the site of definitive treatment. The primary endpoint was the occurrence of a major bile duct injury during laparoscopic cholecystectomy (bile leaks without a major bile duct injury were not tabulated).

RESULTS

Forty-five percent (n = 1,661) of the questionnaires were completed and returned. Mean practice experience was 13.6 years for group A and 5.4 years for group B. At least one injury occurrence was reported by 422 surgeons (37.6%) in group A and 143 surgeons (26.5%) in group B. Forty percent of the injuries in group A occurred during the first 50 cases compared with 22% in group B. Thirty percent of bile duct injuries in group A and 32.9% of all injuries in group B occurred after a surgeon had performed more than 200 laparoscopic cholecystectomies. Independent of the number of laparoscopic cholecystectomies completed since residency, group A surgeons were 39% more likely to report one or more biliary injuries and 58% more likely to report two or more injuries than their counterparts in group B. Bile duct injuries were more likely to be discovered during surgery if a cholangiogram was completed than if cholangiography was omitted (80.9% vs. 45.1%). Sixty-four percent of all major bile duct injuries required biliary reconstruction, and most injuries were definitively treated at the hospital where the injury occurred. Only 14.7% of injuries were referred to another center for repair.

CONCLUSIONS

Accepting that the survey bias underestimates the true frequency of bile duct injuries, residency training decreases the likelihood of injuring a bile duct, but only by decreasing the frequency of early "learning curve" injuries. If one accepts a liberal definition of the learning curve (200 cases), it appears that at least one third of injuries are not related to inexperience but may reflect fundamental errors in the technique of laparoscopic cholecystectomy as practiced by a broad population of surgeons in the United States. Intraoperative cholangiography is helpful for intraoperative discovery of injuries when they occur. Most injuries are repaired in the hospital where they occur and are not universally referred to tertiary care centers.

An automated technique for measuring hippocampal volumes from MR imaging studies

We describe an automated volumetric measure of the hippocampus obtained with software called the Knowledge-Guided MRI Analysis Program (KGMAP). Postmortem MR images from 56 participants in the Nun Study were used to validate the measure. KGMAP-determined volumes strongly correlated with those obtained with manual tracings and neurofibrillary pathologic findings of Alzheimer disease in the hippocampus. KGMAP provides a rapid and accurate estimate of hippocampal volume that is suitable for use in clinical practice.

Resection and advancement of esophageal mucosa. A potential therapy for Barrett's esophagus

BACKGROUND

Barrett's esophagus affects 5-10% of patients with gastroesophageal reflux disease (GERD) and is associated with a 40-fold increased risk of malignant transformation. Ablative therapies may lead to esophageal perforation or stricture formation if applied too liberally and residual glandular tissue and persistent cancer risk if utilized too sparingly.

METHODS

Ten pigs underwent gastrotomy. Mucosa below the gastroesophageal (GE) junction was elevated by saline injections, circumferentially incised, and secured to an orogastric tube. By traction, the distal esophageal mucosa was inverted 10 cm proximally, then returned to the gastric lumen. In group A (n = 4), the mucosa (5 cm) was resected and the remnant was allowed to retract. In group B (n = 4), the mucosa was simply sutured back into its native position. In group C (n = 2), the mucosa (5 cm) was resected and the proximal segment was advanced and sutured to the gastric mucosa. At 6 weeks, or sooner if stricture developed, the animals were killed. Stricture formation was determined by ex vivo barium esophagram and gross assessment. The extent of fibrosis and epithelial healing were established histologically.

RESULTS

Group A (mucosa resected) developed weight loss and anorexia within 4 weeks. Pathology revealed dense fibrotic stricture without reepithelialization. Group B (mucosa elevated/replaced) gained weight after the operation. Histology demonstrated mucosal healing without significant stricture or fibrosis. Group C (mucosa resected/advanced) also thrived postoperatively. Histology confirmed mucosal healing without evidence of retraction or dense stricture.

CONCLUSIONS

Exposure of submucosal tissues causes esophageal stricture. Mucosal coverage minimizes submucosal fibrosis after injury. Mucosal resection and advancement allows healing without stricture and may have therapeutic potential for patients with Barrett's esophagus.

Outcomes of laparoscopic fundoplication for gastroesophageal reflux disease and paraesophageal hernia

BACKGROUND

Laparoscopic fundoplication has become the standard for operative treatment of gastroesophageal reflux disease (GERD).

METHODS

We reviewed our experience with 1,000 consecutive patients receiving laparoscopic fundoplication for GERD (n = 882) or paraesophageal hernia (n = 118) between October 1991 and July 1999. Patients with achalasia and failed fundoplication were excluded from analysis. All the patients were evaluated preoperatively by upper endoscopy, esophageal manometry, and barium swallow. After 1994, 24-h pH monitoring was performed selectively in patients with extraesophageal symptoms and/or those without erosive esophagitis. There were 490 men 510 women in this review. Their mean age was 49 years. Procedures performed were 360 degrees floppy fundoplication (n = 879), 360 degrees fundoplication without fundus mobilization (Rossetti) (n = 22), 270 degrees posterior fundoplication (n = 96), and anterior fundoplication (n = 2). Esophageal lengthening procedure (Collis gastroplasty) was performed in combination with fundoplication in 15 patients. In seven patients the treatment was converted to open fundoplication.

OUTCOMES

The average length of hospitalization was 2.2 days, and 136 patients stayed longer than 2 days. Major complications occurred in 21 patients: esophageal perforation (n= 10), acute paraesophageal herniation (n = 4), splenic bleeding (n = 2), cardiac arrest (n = 1), pneumonia (n = 3), and testicular abscess (n = 1). Additional operations were required to manage the complications in 14 patients (70%): Four of these procedures were performed emergently, and 10 patients underwent reoperation between 6 h and 10 days. There were three deaths, all of which involved elderly patients with paraesophageal hernia. There were 35 late failures requiring reoperation for recurrence of GERD or development of new symptoms: The treatment of 32 patients was revised laparoscopically, and 4 patients required laparotomy. Beyond 1 year (median follow-up period, 27 months), 94% of the reviewed patients were satisfied with their surgical outcome.

A randomized, controlled trial of methotrexate versus placebo in early diffuse scleroderma

OBJECTIVE

Early diffuse scleroderma (systemic sclerosis; SSc) has no proven treatment. This study was undertaken to examine the efficacy of methotrexate (MTX) in improving the skin and other disease parameters in early diffuse SSc.

METHODS

Seventy-one patients with diffuse SSc of <3 years' duration were enrolled in a multicenter, randomized, placebo-controlled, double-blind trial. Thirty-five patients were treated with MTX and 36 with placebo. Treatment was administered for 12 months. The primary outcome measures were skin score (as determined with 2 different indices) and physician global assessment.

RESULTS

At baseline, there were no statistically significant differences in skin scores, carbon monoxide diffusing capacity (DLco), physician global assessment, or other secondary outcome measurements between the 2 treatment groups. At study completion, results slightly favored the MTX group (mean +/- SEM modified Rodnan skin score 21.4+/-2.8 in the MTX group versus 26.3+/-2.1 in the placebo group [P < 0.17]; UCLA skin score 8.8+/-1.2 in the MTX group versus 11.0+/-0.9 in the placebo group [P < 0.15]; DLco in the MTX group 75.7+/-4.6 versus 61.8+/-3.4 in the placebo group [P < 0.2]). In addition, physician global assessment results favored MTX (P < 0.035), whereas patient global assessment did not differ significantly between groups. When between-group differences for changes in scores from baseline to 12 months were examined using intent-to-treat methodology, MTX appeared to have a favorable effect on skin scores (modified Rodnan score -4.3 in the MTX group versus 1.8 in the placebo group [P < 0.009]; UCLA score -1.2 in the MTX group versus 1.2 in the placebo group [P < 0.02]), but differences in the degree of change in the DLco and physician global assessment were not significant. For the UCLA skin score, these differences in results were not statistically significant after adjustment for baseline differences in sex distribution and steroid use. Dropout rates were similar in the 2 groups.

CONCLUSION

Although results of this trial demonstrated a trend in favor of MTX versus placebo in the treatment of early diffuse SSc, the between-group differences were small and the power to rule out false-negative results was only 50%. Our findings do not provide evidence that MTX is significantly effective in the treatment of early diffuse SSc.

Assessing laparoscopic manipulative skills

BACKGROUND

The rapid emergence of laparoscopic surgery over the past decade has highlighted the need for teaching and assessing laparoscopic manipulative skills. Most analyses consist of a measurement of the time to complete a specified task and a subjective assessment by an observer. Objective assessments of accuracy in the performance of manipulative skills have been lacking. To quantify both speed and accuracy during laparoscopic skill performance, we have developed a skills assessment device (SAD) using a laparoscopic simulator platform and computer-based skills assessment software that precisely measures an instrument's movement during performance of timed laparoscopic manipulations.

STUDY DESIGN

The SAD device measures the time necessary for an operator to complete a task, and the movements of the working end of laparoscopic instruments in three dimensions. Ten nonsurgeons performed 10 repetitions of a standardized laparoscopic manipulation. Data were captured in real time for both hands on a personal computer. Accuracy was determined by calculating the sum of all distances traveled. Duration was measured in seconds. Results are group means.

RESULTS

The time necessary to perform defined laparoscopic manipulative skills improved dramatically during the first 3 repetitions and then stabilized. However, accuracy of manipulations continued to improve over all 10 repetitions.

CONCLUSIONS

When untrained subjects are learning a laparoscopic manipulative task, measurement of time alone fails to account for the more protracted learning curve for accuracy. Therefore, devices and training programs that fail to consider objective assessments of accuracy may overestimate laparoscopic proficiency.

Recursive partitioning analysis of locoregional recurrence patterns following mastectomy: implications for adjuvant irradiation

PURPOSE

Postmastectomy irradiation improves overall survival for breast cancer patients at high risk for locoregional recurrence (LRR). The objective of this study was to use recursive partitioning analysis (RPA) to define patient subgroups at high risk for LRR following mastectomy.

PATIENTS AND METHODS

A cohort of 1031 patients treated on prospective trials with mastectomy and doxorubicin-based chemotherapy without irradiation was analyzed. The variables considered in the RPA were tumor size, number of involved nodes, number of nodes examined, and percentage of nodes involved (nodes involved/nodes examined). The endpoint was LRR +/- distant metastasis. Only patients with complete data were analyzed (n = 913). Median follow-up was 8 years (range, 0.7-22 years).

RESULTS

Involvement of 20% or more of the lymph nodes examined was the most significant variable predicting LRR. Three risk categories were defined. Patients with 20% or more involved nodes and tumors of 3.5 cm or more were at greatest risk for LRR (41% at 8 years). An intermediate-risk group included patients with 20% or more involved nodes and tumors of less than 3.5 cm as well as those with less than 20% involved nodes and tumor size of 5 cm or greater (18% at 8 years). Patients with less than 20% involved nodes and tumor size of less than 5 cm were at lowest risk for LRR (10% at 8 years).

CONCLUSION

Tumor size and extent of nodal involvement play interrelated roles in predicting LRR following mastectomy and systemic therapy. Patients with 20% or greater involved nodes and those with less than 20% nodes and tumors of 5.0 cm or greater are at significant risk of LRR and should be considered for postoperative irradiation.

A hypothalamic stroke producing recurrent hemihyperhidrosis

A 40-year-old man awoke with exuberant sustained sweating of the entire left side of the body, which became intermittent over the next few days. MRI indicated a single linear hyperintensity in the right posterior hypothalamus, diminishing on a repeat scan. He continues to have episodes of left unilateral sweating precipitated by exercise or minor infection.

Urban-rural differences in a memory disorders clinical population

OBJECTIVES

To compare patient characteristics and family perceptions of patient function at one urban and one rural memory disorders clinic.

DESIGN

Secondary, cross-sectional data analyses of an extant clinical database.

SETTING/PARTICIPANTS

First time visits (n = 956) at two memory disorders clinics.

MEASUREMENTS

Patient and family-member demographics and assessment results for the Mini-Mental State Examination (MMSE), instrumental activities of daily living (IADLs), activities of daily living (ADLs), the Memory Change and Personality Change components of the Blessed Dementia Rating Scale, and the Revised Memory and Behavior Problems Checklist.

RESULTS

In both clinics, patients and family members were more likely female. The typical urban clinic patient was significantly more likely to be living in a facility and more educated than the typical rural patient. Urban and rural patients did not show significant differences in age- and education-adjusted MMSE scores or raw ADL/IADL ratings, but the urban family members reported more memory problems, twice as many personality changes, more-frequent behavior problems, and more adverse reactions to problems.

CONCLUSION

Physicians who practice in both urban and rural areas can anticipate differences between patients, and their families, who seek a diagnosis of memory disorders. Our most important finding is that despite similarities in reported functional abilities, urban families appear to be more sensitive to and more distressed by patients' cognitive and behavioral symptoms than rural families. These differences may reflect different underlying needs, and should be explored in further research.

Total Synthesis of Dendroamide A, a Novel Cyclic Peptide That Reverses Multiple Drug Resistance

Dendroamide A (1) was isolated from a blue-green alga on the basis of its ability to reverse drug resistance in tumor cells that overexpress either of the transport proteins, P-glycoprotein or MRP1. Because of this activity, methods for the synthesis of analogues of this oxazole- and thiazole-containing cyclic peptide have been developed, and the total synthesis of 1 has been completed. Highlights of the synthetic strategy are as follows: (1) a dicyclohexylcarbodiimide coupling of D-Ala and L-Thr, followed by reaction with Burgess reagent and DBU-assisted oxidation to form D-Ala-oxazole; (2) formation of D-Val-thiazole and D-Ala-thiazole via modified Hantzsch reactions; and (3) use of molecular modeling to select the preferred precursor for the final cyclization of the peptide analogue. Synthetic 1 demonstrated spectral properties identical to those of the natural product and reversed P-glycoprotein-mediated drug resistance more effectively than MRP1-mediated resistance. Certain of the synthetic precursors had biological activity, indicating that cell permeability and peptide cyclization are necessary for optimal activity. Thus, the structure and the biological activities of the natural product are confirmed, and methods for the synthesis of analogues for further structure-activity explorations are defined.

Differences in functional magnetic resonance imaging activation by category in a visual confrontation naming task

OBJECTIVE

Cortical processing involved in seemingly similar tasks may differ in important ways. The authors mapped cortical regions engaged in a commonly performed picture naming task, seeking differences by semantic category. Functional magnetic resonance imaging was used during presentation of standardized line drawings in 18 healthy right-handed female participants, comparing living versus nonliving entities. During visual naming, across categories there was strong activation of left frontal (BA45/47), bilateral temporo-occipital junction (BA19), and inferior temporal regions (BA36/37). Activation of right inferior temporal cortex (BA19 and BA37) was greater during naming of living versus nonliving category items. No category differences in activation strength in the left temporal lobe were observed. The authors conclude that visual semantic operations may involve visual association cortex in the right temporal lobe in women.

Genital infection and termination of pregnancy: Are patients still at risk?

OBJECTIVES

To identify the treatment patterns and early complication rates in women identified with a genital infection prior to a termination of pregnancy (TOP) and to re-assess our earlier work on contact attendance and treatment. The aim was to refine current prophylactic measures to provide the most efficient and effective way of reducing post-termination complications.

METHOD

Six-month retrospective analysis of all women with genital Chlamydia trachomatis or Neisseria gonorrhoeae identified prior to TOP. Data on the timing of positive results and treatment in relation to the TOP were recorded. Clinical signs of pelvic infection and the success of contact tracing and treatment were noted.

RESULTS

Forty women were identified with infection, 31 (78%) proceeded to TOP; only five were treated adequately in the peri-TOP period. Twenty-six (84%) of the women undergoing TOP attended the genitourinary medicine (GUM) department after the TOP and received antimicrobial therapy where necessary. In total, four women (10%) were untreated. Approximately two thirds of results were reported prior to, or on the day of, the TOP. The majority of TOPs (71%) were carried out at 5 days or less from the initial assessment. Clinical signs of post-TOP pelvic inflammation developed in seven (28%) women with chlamydial infection. Contact tracing was successful in 24 (69%) of the 35 women who attended the GUM department.

CONCLUSION

The debate about the best option for the most effective management of women undergoing TOP continues. The options with respect to C. trachomatis include universal prophylaxis, screening and treating as necessary, or a 'belt and braces' approach of screening all and treating all. Fundamental is the continuation of active contact tracing and GUM remains integral to this.

A prospective randomized comparison of laparoscopic appendectomy with open appendectomy: Clinical and economic analyses

BACKGROUND

Previous randomized studies of laparoscopic appendectomy produced conflicting recommendations, and the adequacy of sample sizes is generally unknown. We compared clinical and economic outcomes after laparoscopic and open appendectomy in a sample of predetermined statistical power.

METHODS

A pre-study power analysis suggested that 200 randomized patients would yield 80% power to show a mean decrease of 1.3 days' hospitalization. One hundred ninety-eight patients with a preoperative diagnosis of acute appendicitis were randomized prospectively to laparoscopic or open appendectomy. Economic analysis included billed charges, total costs, direct costs, and indirect costs associated with treatment.

RESULTS

Laparoscopic appendectomy took longer to perform than open appendectomy (median, 107 vs 91 minutes; P <.01) and was associated with fewer days to return to a general diet (mean, 1.6 versus 2.3 days; P <.01), a shorter duration of parenteral analgesia (mean, 1.6 versus 2.2 days; P <.01), fewer morphine-equivalent milligrams of parenteral narcotic (median, 14 mg versus 34 mg; P =.001), a shorter postoperative hospital stay (mean, 2.6 versus 3.4 days; P <.01), and earlier return to full activity (median, 14 versus 21 days; P <.02). However, operative morbidity and time to return to work were comparable. Billed charges and direct costs were not significantly different in the 2 groups ($7711 versus $7146 and $5357 versus $4945, respectively), but total costs (including indirect costs) of laparoscopic appendectomy were, on average, nearly $2400 less, given the shorter length of stay and abbreviated recuperative period ($11,577 versus $13,965). Subgroup analyses suggested the benefit of a laparoscopic approach for uncomplicated appendicitis and for patients with active lifestyles.

CONCLUSIONS

While laparoscopic appendectomy is associated with statistically significant but clinically questionable advantages over open appendectomy, a laparoscopic approach is relatively less expensive. The estimated difference in total costs of treatment (direct and indirect costs) was at least $2000 in more than 60% of the bootstrapped iterations. The economic significance and implications favoring a laparoscopic approach cannot be ignored.

Neural substrates of facial emotion processing using fMRI

We identified human brain regions involved in the perception of sad, frightened, happy, angry, and neutral facial expressions using functional magnetic resonance imaging (fMRI). Twenty-one healthy right-handed adult volunteers (11 men, 10 women; aged 18-45; mean age 21.6 years) participated in four separate runs, one for each of the four emotions. Participants viewed blocks of emotionally expressive faces alternating with blocks of neutral faces and scrambled images. In comparison with scrambled images, neutral faces activated the fusiform gyri, the right lateral occipital gyrus, the right superior temporal sulcus, the inferior frontal gyri, and the amygdala/entorhinal cortex. In comparisons of emotional and neutral faces, we found that (1) emotional faces elicit increased activation in a subset of cortical regions involved in neutral face processing and in areas not activated by neutral faces; (2) differences in activation as a function of emotion category were most evident in the frontal lobes; (3) men showed a differential neural response depending upon the emotion expressed but women did not.

National market cow and bull beef quality audit-1999: a survey of producer-related defects in market cows and bulls

The 1999 National Market Cow and Bull Beef Quality Audit comprised face-to-face interviews with industry representatives (n = 49); in-plant evaluations of cattle in holding pens (n = 3,969), carcasses on harvest floors (n = 5,679), and in carcass coolers (n = 4,378); and a strategy workshop. Face-to-face interviews suggested that the beef industry was most frequently concerned about the presence of antibiotic residues in carcasses, presence of lead shot in carcasses, and price discovery for carcasses following excessive trimming of bruises and testing due to arthritic joints, pathogens, or antibiotic residues. Although live animal evaluations determined that 73.4% of beef cows, 60.8% of dairy cows, 63.7% of beef bulls, and 70.9% of dairy bulls did not exhibit evidence of lameness, losses due to lameness were greater (P < 0.05) than in the 1994 National Non-Fed Beef Quality Audit. In-plant audits revealed that 88.9, 10.3, and 88.2% of cow carcasses and 18.9, 21.2, and 52.9% of bull carcasses had inadequate muscling, arthritic joints, and at least 1 bruise, respectively, all of which resulted in greater (P < 0.05) losses than the same defects in 1994. Audits revealed that 88.9% of cow carcasses and 18.9% of bull carcasses were lightly muscled, resulting in greater (P < 0.05) losses for cow carcasses, and similar (P > 0.05) losses for bull carcasses, than the same defect in the 1994 audit. Also, 14.5 and 30.8% of cow carcasses and 6.9 and 5.9% of bull carcasses had excess external fat and yellow-colored external fat, respectively, which was an improvement (P < 0.05) over 1994 results. In aggregate, 24.1, 19.2, 7.2, 6.7, 9.5, and 1.1% of livers, tripe, hearts, heads, tongues, and whole cattle or carcasses, respectively, were condemned and 60.6, 2.4, and 46.5% of cattle had hide damage from latent defects, insect damage, and brands, respectively. Condemnation rates were generally lower (P < 0.05), but tongue condemnations and frequency of branded hides were higher (P < 0.05) than in 1994. Producers should promote value in cows and bulls by managing to minimize quality defects, monitoring health and condition, and marketing in a timely manner. Using these techniques, producers might have recaptured $13.82, $27.50, and $27.50, respectively, for each cow or bull harvested in 1999.

Nissen fundoplication improves gastric motility in patients with delayed gastric emptying

BACKGROUND

Fundoplication hastens gastric emptying in pediatric patients with gastroesophageal reflux disease (GERD). However, among adult GERD patients with impaired gastric emptying, the degree of improvement offered by fundoplication and the value of pyloroplasty are less well defined. Therefore, we compared outcomes in GERD patients with delayed gastric emptying after fundoplication alone or fundoplication with pyloroplasty.

METHODS

Of 616 consecutive GERD patients who submitted to primary fundoplication (601 laparoscopic) between October 1991 and October 1997, 82 underwent preoperative solid-phase nuclear gastric emptying analysis. Of these, 25 had delayed gastric emptying (half-time >100 min). Of 12 patients with emptying half-times between 100 and 150 min, one underwent pyloroplasty at the time of Nissen fundoplication. Of 13 patients with emptying half-times >150 min, 11 had pyloroplasty at the time of Nissen fundoplication. Patients were asked to use a 0 ("none") to 4 ("incapacitating") scale to describe the severity of their symptoms of heartburn, regurgitation, dysphagia, bloating and diarrhea preoperatively and at 6 weeks and 1 year postoperatively. Eight patients consented to a postoperative analysis of gastric emptying.

RESULTS

One year after fundoplication, patients with delayed gastric emptying and controls reported a similar improvement in heartburn, regurgitation, and dysphagia, with no increase in undesirable side effects such as bloating and diarrhea. Among the patients with delayed gastric emptying who consented to undergo a repeat gastric emptying study after their operation, fundoplication alone provided a 38% improvement (p < 0.05) in gastric emptying, whereas fundoplication with pyloroplasty resulted in a 70% improvement in gastric emptying (p < 0.05).

CONCLUSION

Fundoplication improves gastric emptying. The addition of pyloroplasty results in even greater improvement and may have particular value for patients with severe gastric hypomotility.

Structure-activity studies of substituted quinoxalinones as multiple-drug-resistance antagonists

A significant problem in the clinical treatment of cancer relates to the development of tumor resistance to many chemotherapeutic agents. Acquired drug resistance is often mediated through overexpression of membrane transport proteins that effectively efflux anticancer agents. Two of the best-studied transporters, P-glycoprotein (Pgp) and MRP1, have pharmacological properties that only partially overlap. In our search for improved drug-resistance antagonists, we have identified a family of substituted quinoxalines that selectively antagonizes Pgp over MRP1. Consequently, a focused library of congeners was designed and synthesized starting with a parent bromomethylquinoxalinone. This parent quinoxalinone was then condensed with a series of phenols to yield a family of substituted phenoxymethylquinoxalinones. These compounds were evaluated for their toxicity toward drug-sensitive MCF-7 breast carcinoma cells and for their abilities to antagonize Pgp and MRP1 in drug-resistant cell lines (NCI/ADR and MCF-7/VP, respectively). The results of this structure-activity study indicate that compounds with carbonyl substitutions of the phenoxy group (ester, amide, or ketone moieties) demonstrate excellent antagonism of Pgp while having relatively low toxicity toward drug-sensitive cells. Importantly, none of these compounds antagonized MRP1. Because of their transporter selectivity, we predict that substituted quinoxalinones may be more effective MDR modulators in vivo than are nonselective transporter antagonists.