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B Massey

Publications and source records attributed to B Massey.

10 recordsLinked to original sources
PubMed2001

Post-fundoplication symptoms: the role for endoscopic assessment of fundoplication integrity.

BACKGROUND: Fundoplication is now almost exclusively a laparoscopic procedure. The aim of this study was the comparison of the diagnostic usefulness of endoscopy and barium esophagram in the detection of fundoplication abnormalities. METHODS: Twenty-two patients presented with symptoms post-laparoscopic (Nissen) fundoplication that included dysphagia (14 patients), heartburn (5 patients), dyspepsia (2 patients), and chest pain (1 patient). Barium esophagram and upper endoscopy were performed in all patients and the results were compared. Key features included presence of esophagitis, resistance to endoscope passage, location of the wrap relative to the diaphragmatic hiatus, location of squamocolumnar junction greater than 1 cm proximal to the wrap zone, and the appearance of the wrap (intact, loose, disrupted, or tight). RESULTS: The key features explained symptoms in 20 of 22 patients. Endoscopy detected twice as many key features as radiography. Disruption of the wrap or excessive proximal location of the squamocolumnar junction proximal to the wrap zone were the most incriminating endoscopic findings. Resistance to endoscope passage was rarely encountered and the esophagram was more accurate in detecting an overly tight wrap. CONCLUSIONS: Endoscopic evaluation is more accurate than barium esophagram in detecting post-fundoplication abnormalities. The appearance of the fundoplication wrap and an abnormal proximal location of the squamocolumnar junction appear to be major endoscopic clues in diagnosis of post-fundoplication problems.

Barium Sulfate↗
PubMed2001

Liposuction as an adjunct procedure in reduction mammaplasty.

Liposuction has been recognized as a useful adjunct to breast reduction surgery for fine contouring of adjacent areas to achieve aesthetic balance and preservation of nipple sensation. In particular, the liposuction technique has provided an acceptable way of treating the "fat roll" of the lateral portion of the breast, which extends to the axilla and lateral chest. The purpose of this study was to review the authors' approach to adjunctive lipoplasty with breast reduction surgery and to review their experience. Examination of their own results in 70 consecutive women who underwent reduction mammaplasty in 1998 by the senior surgeon did not reveal any substantial difference in the complication rate of those women who had adjunctive liposuction with their breast reduction surgery vs. those who did not. All complications such as fat necrosis, cellulitis, and seromas were confined to the breast and were not related to the liposuction. Furthermore, there was no additional morbidity associated with ultrasonic liposuction compared with traditional suction-assisted lipectomy. Their experience indicates that patients undergoing reduction mammaplasty may benefit aesthetically from adjunct lateral chest wall liposuction without additional morbidity.

Adolescent↗
PubMed1998

The duck hepatitis B virus polymerase is activated by its RNA packaging signal, epsilon.

The epsilon stem-loop at the 5' end of the pregenomic RNA of the hepatitis B viruses is both the primary element of the RNA packaging signal and the origin of reverse transcription. We have previously presented evidence for a third essential role for epsilon, that of an essential cofactor in the maturation of the viral polymerase (J. E. Tavis and D. Ganem, J. Virol. 70:5741-5750, 1996). In this case, binding of epsilon to the polymerase is proposed to induce a physical alteration to the polymerase that is needed for it to develop enzymatic activity. Three lines of evidence employing duck hepatitis B virus supporting this hypothesis are presented here. First, an unusual DNA polymerase activity employing exogenous RNAs (the trans reaction) that was originally discovered with recombinant duck hepatitis B virus polymerase expressed in Saccharomyces cerevisiae yeasts was shown to be an authentic property of the viral polymerase. The trans reaction was found to be template-dependent reverse transcription of the exogenous RNA. The trans reaction occurred independently of the hepadnavirus protein-priming mechanism, yet it was still strongly stimulated by epsilon. This directly demonstrates a role for epsilon in activation of the polymerase. Second, the reverse transcriptase domain of the polymerase was shown to be physically altered following binding to epsilon, as would be expected if the alteration was required for maturation of the polymerase to an enzymatically active form. Finally, analysis of 15 mutations throughout the duck hepatitis B virus polymerase demonstrated that the epsilon-dependent alteration to the polymerase was a prerequisite for DNA priming, reverse transcription, and the trans reaction.

Animals↗
PubMed1997

Myocardial infarction and regulatory myosin light chain.

Myosin from cardiac muscle consists of two heavy chains and two pairs of light chain. Regulatory myosin light chain (RMLC) is phosphorylated by a Ca2+ and calmodulin dependent myosin light chain kinase. The impact of experimental myocardial infarction on cardiac RMLC was studied. The left anterior descending coronary artery of rabbits was ligated. Three, 7 and 14 days later the animals were euthanized, sections of the heart were frozen in liquid nitrogen and later subjected to 2-dimensional electrophoresis. Isoelectric focusing was carried out at a pH range of 4.5-5.4. Reproducible patterns of protein separation showed four spots with proteins of phosphorylatable regulatory light chains shifted to a more negative pH as compared to essential light chain. We investigated changes in phosphorylation of RMLC in infarcted heart muscle. As compared to sham operated animals, a decline in phosphorylation of RMLC was present in both infarcted and non-infarcted portions of the left ventricle; the latter was significant 7 days following the onset of ischemia. In contrast, the decline in percent phosphorylation in the infarcted area was not significant. The amount of RMLC decreased significantly in the infarcted portion. A highly significant reduction in the percent of viable cardiomyocytes accompanied the decline in phosphorylation. There was a significant correlation of RMLC following administration of isoproterenol, 7 and 14 days following onset of ischemia. Only faint traces of essential atrial myosin light chain (ALC-1) were present in the non-infarcted portion of the left ventricle. No correlation was found between percent phosphorylation and the amount of RMLC (density) following infusion of saline or isoproterenol. Isoproterenol significantly increased percent phosphorylation without altering the amount of RMLC protein. We conclude that myocardial infarction profoundly affects regulatory myosin light chain phosphorylation in the infarcted and non-infarcted areas of the myocardium and that RMLC plays a significant part in myocardial contractility.

Animals↗
PubMed1997

Apoptosis in experimental myocardial infarction in situ and in the perfused heart in vitro.

We report the appearance of apoptotic cells in experimental myocardial infarction (rabbit heart) in in situ and in vitro preparations. Apoptosis was recognized by intravital staining with Hoechst 33342 (Ho342), by nick-end labeling (TUNEL) and by DNA laddering. A steady rise in the relative number of apoptotic cardiomyocytes (apoptotic index) was noted in in situ preparations. Apoptosis was first noted 6 h after the onset of ischemia with its highest value occurring after 72 h. Apoptotic nuclei were absent in remote areas of the left and right ventricles. Apoptotic nuclei within the infarcted area showed diminished intensity of Ho342 fluorescence. Three days after ischemia, a border zone adjacent to the infarcted area consisting of apoptotic macrophages was recognized. A novel finding was the appearance of apoptotic cardiomyocytes in the isolated perfused ischemic heart. Occurring as early as 50 min after the onset of ischemia, a high apoptotic index was present adjacent to the ligature placed around the coronary artery. This observation provides the opportunity to selectively examine factors leading to apoptosis in the ischemic heart under controlled experimental conditions.

Animals↗
PubMed1996

A comparative study of unsedated transnasal esophagogastroduodenoscopy and conventional EGD.

BACKGROUND: A significant portion of the cost and complications associated with conventional esophagogastroduodenoscopy (EGD) is attributed to conscious intravenous sedation, which usually results in loss of work on the day of the endoscopy. Earlier studies have described the feasibility and safety of unsedated transnasal EGD in normal volunteers. METHODS: We compared the diagnostic yield and patient acceptability of this new technique performed first, with conventional EGD performed second in 24 outpatients. RESULTS: The sensitivity of transnasal EGD was 89% and its specificity was 97%. Transnasal EGD was more acceptable and less stressful to the patients than conventional EGD (p < 0.05). Oxygen saturation and blood pressure did not change during transnasal EGD. CONCLUSION: Transnasal EGD is feasible, safe, and well tolerated by patients. Specificity of transnasal EGD is similar to, but its sensitivity is lower than, conventional EGD. By eliminating the need for sedation-related work loss and postprocedural monitoring, transnasal EGD potentially is more cost-effective than conventional EGD.

Adult↗
PubMed1989

Opening mechanisms of the human upper esophageal sphincter.

Our goals in this study were to evaluate the mechanisms operative in swallow-associated opening of the upper esophageal sphincter (UES) and to determine the dynamics of fluid flow across the sphincter. For this purpose, we obtained concurrent videofluorographic and manometric studies of 2- to 30-ml barium swallows in 15 normal subjects. We found that the resting UES high-pressure zone corresponded closely with the location of the cricopharyngeus. The findings indicated that manometric UES relaxation and anterior hyoid traction on the larynx invariably preceded UES opening. With graded increases in bolus volume, progressive increases occurred in UES diameter, cross-sectional area, flow duration, and transsphincteric flow rate. Intrabolus pressure upstream to the UES and within the UES at its opening during transsphincteric flow of barium remained within a narrow physiological range of less than 10 mmHg up to a bolus volume of 10 ml. With increases in bolus volume, anterior hyoid movement, UES relaxation, and UES opening occurred sooner in the swallow sequence to accommodate the early entry of large boluses into the pharynx. We conclude that during swallowing 1) normal UES opening involves sphincter relaxation, anterior laryngeal traction, and intrabolus pressure, 2) volume-dependent adaptive changes in UES dimension accommodate large bolus volumes and flow rates with minimal requirement for increases in upstream, or intrasphincteric, intrabolus pressure or UES opening duration, and 3) volume-dependent changes in UES dimensions as well as timing of UES relaxation and opening indicate a sensory feedback mechanism that modulates some components of the swallow response generated by the brain stem swallow centers.

Adult↗