Columnar metaplasia in the esophageal remnant after esophagectomy: a systematic review.

Barrett's metaplasia is a well-recognized risk factor for esophageal adenocarcinoma. It is believed to develop in response to the injurious effects of gastroesophageal reflux. Following subtotal esophagectomy and reconstruction with a gastric conduit, many patients experience profound reflux into the remnant esophagus. Barrett's-like epithelium has been described in these patients, and they have been identified as a potential human model in which to study the early events in the development of metaplasia. This phenomenon also raises clinical concerns about the long-term fate of the esophageal remnant following surgery and the potential for further malignant change. This systematic review summarizes the literature on the prevalence and timing of Barrett's metaplasia occurring after esophagectomy, reviews the evidence regarding risk factors and malignant progression in such patients, and considers the implications for clinical practice.

Blinded 12-week comparison of once-daily indacaterol and tiotropium in COPD.

Two, once daily (q.d.) inhaled bronchodilators are available for the treatment of chronic obstructive pulmonary disease (COPD): the ß(2)-agonist indacaterol and the anticholinergic tiotropium. This blinded study compared the efficacy of these two agents and assessed their safety and tolerability. Patients with moderate-to-severe COPD were randomised to treatment with indacaterol 150 µg q.d. (n=797) or tiotropium 18 µg q.d. (n=801) for 12 weeks. After 12 weeks, the two treatments had similar overall effects on "trough" (24 h post-dose) forced expiratory volume in 1 s. Indacaterol-treated patients had greater improvements in transition dyspnoea index (TDI) total score (least squares means 2.01 versus 1.43; p<0.001) and St George's Respiratory Questionnaire (SGRQ) total score (least squares means 37.1 versus 39.2; p<0.001; raw mean change from baseline -5.1 versus -3.0), and were significantly more likely to achieve clinically relevant improvements in these end-points (indacaterol versus tiotropium odds ratios of 1.49 for TDI and 1.43 for SGRQ, both p<0.001). Adverse events were recorded for 39.7% and 37.2% of patients in the indacaterol and tiotropium treatment groups, respectively. The most frequent adverse events were COPD worsening, cough and nasopharyngitis. Both bronchodilators demonstrated spirometric efficacy. The two treatments were well tolerated with similar adverse event profiles. Compared with tiotropium, indacaterol provided significantly greater improvements in clinical outcomes.

Binding of dimeric aminoglycosides to the HIV-1 rev responsive element (RRE) RNA construct.

Through a series of elegant fluorescence measurements, particularly through stopped-flow kinetic measurements, it was recently demonstrated that aminoglycoside antibiotics are able to bind to the HIV-1 Rev responsive element (RRE) RNA construct in more than a 1:1 stoichiometry (Lacourciere, K. A.; Stivers, J. T.; Marino, J. P. Biocheminstry 2000, 39, 5630). Here, we present the binding study results of dimeric neomycin ligands through fluorescence anisotropy studies, to the HIV-1 RRE RNA construct. The dimeric neomycin molecules are observed to be able to bind the HIV-1 RRE RNA construct approximately 17-fold higher when compared to the monomeric neomycin, lending evidence that there are indeed two or more neomycin binding sites within the HIV-1 RRE construct.

Recent developments in medicine and law.

This article addresses important developments in the field of medicine and the law during the last year and highlights some of the significant areas of law affecting health care providers that should be considered. Actions against health care providers may include challenges to peer review immunity, allegations concerning the practice of medicine across state lines without a license, and even accusations of wrongfully assisting a patient to commit suicide. These areas are addressed in turn by this article. Finally, antitrust developments over the last year are briefly addressed as an emerging area of concern for providers forming complex practice networks in today's health care arena.

An integrated, hospital information system based obstetrical medical record and database.

Described in this paper is the implementation and integration of an obstetrical medical record and database into an existing hospital information system. A unique feature of this system was the integration of existing data captured by the established hospital information systems with the newly implemented obstetrical database to form a complete patient data profile. This complete database integrated data from hospital functions such as demographic data obtained at patient registration, outpatient visits and tests, inpatient admission historical data, tests and procedures, newborn data and miscellaneous data required for birth registration. An important second feature was the utilization of physicians and nurses to enter the obstetrical data. This permitted immediate access to patient data from any hospital information system terminal, immediate retrieval for generating reports, and subsequently, ad hoc queries, statistical analysis and the electronic transfer of birth registration data to the State Vital Statistics Registry.

Isolation and sequencing of cDNA clones encoding ethylene-induced putative peroxidases from cucumber cotyledons.

A cDNA library from ethephon-treated cucumber cotyledons (Cucumis sativus L. cv. Poinsett 76) was constructed. Two cDNA clones encoding putative peroxidases were isolated by means of a synthetic probe based on a partial amino acid sequence of a 33 kDa cationic peroxidase that had been previously shown to be induced by ethylene. DNA sequencing indicates that the two clones were derived from two closely related RNA species that are related to published plant peroxidase sequences. Southern analysis indicates that there are 1-5 copies in a haploid genome of a gene homologous to the cDNA clones. The deduced amino acid sequences are homologous with a tobacco (55% sequence identity), a horseradish (53%), a turnip (45%), and a potato (41%) peroxidase. The cloned sequences do not encode the 33 kDa peroxidase from which the original synthetic probe was been derived, but rather other putative peroxidases. An increase in the level of mRNA is evident by 3 hours after ethephon or ethylene treatment and plateaus by 15 hours.

Hormonal regulation and distribution of peroxidase isoenzymes in the Cucurbitaceae.

Ethylene enhanced the levels of peroxidases in the roots, stems, leaves, and cotyledons of 2-week-old cucumber Cucumis sativus cv Poinsett 76 seedlings. Antibodies to the isoelectric point (pl) 9 and pl 4 isoenzymes were used in a radial immuno-diffusion assay to demonstrate that ethylene induced similar peroxidases in other cultivars of C. sativus, other species of Cucumis and other genera of Cucurbitaceae. Examination of ethylene-induced peroxidases, using isoelectric focusing gels, demonstrated the presence of a series of other peroxidases, mostly slightly acidic, whose isoelectric focusing pH was approximately 6. These pl 6 peroxidases were partially purified on a cation exchange column. Ouchterlony double diffusion gels indicated that these proteins cross-reacted with antibodies to both the pl 9 and pl 4 peroxidase. The data presented here suggest that the induction of peroxidase isoenzymes during ethylene-induced senescence is a common response in this family of plants. In addition, antibody and isoelectric focusing studies indicate that both acidic and basic peroxidase are highly conserved in members of this family.

Hormonal Regulation, and Intracellular Localization of a 33-kD Cationic Peroxidase in Excised Cucumber Cotyledons.

Ethylene enhanced chlorosis and levels of 33-kilodalton cationic peroxidase (33-CPO) in excised cucumber (Cucumis sativus L. cv ;Poinsett 76') cotyledons. Compared to other hormones, such as kinetin, indoleacetic acid, gibberellic acid, and abscisic acid, ethylene was the only effective promoter of 33-CPO synthesis. The hypothesis that peroxidase plays a role in chlorophyll degradation was tested by comparing levels of 33-CPO in cotyledons treated with compounds thought to either retard (kinetin, indoleacetic acid and gibberellic acid), or promote (abscisic acid and methyl jasmonate [MJ]) senescence. It was concluded that 33-CPO did not play a role in senescence since no direct correlation between chlorophyll content and 33-CPO was observed. MJ was as effective as ethylene in inducing senescence. However, ethylene did not appear to be involved in the action of MJ. Using immunocytochemistry, 33-CPO was found to be located primarily around starch grains and near the plasmalemma. High levels of 33-CPO were also found in cells destined to be vascular tissue.

Induction of 33-kD and 60-kD Peroxidases during Ethylene-Induced Senescence of Cucumber Cotyledons.

Ethylene enhanced the senescence of cucumber (Cucumis sativus L. cv ;Poinsett 76') cotyledons. The effect of 10 microliters per liter ethylene was inhibited by 1 millimolar silver thiosulfate, an inhibitor of ethylene action. An increase in proteins with molecular weights of 33 to 30 kilodaltons and lower molecular weights (25, 23, 20, 16, 12, and 10 kilodaltons) were observed in sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels after ethylene enhanced senescence. The measurement of DNase and RNase activity in gels indicated that these new proteins were not nucleases. Two proteins from ethylene-treated cotyledons were purified on the basis of their association with a red chromaphore and subsequently were identified as peroxidases. The molecular weights and isoelectric points (pI) of two of these peroxidases were 33 kilodaltons (cationic, pI = 8.9) and 60 kilodaltons (anionic, pI = 4.0). The observation that [(35)S]Na(2)SO(4) was incorporated into these proteins during ethylene-enhanced senescence suggests that these peroxidases represent newly synthesized proteins. Antibodies to the 33-kilodalton peroxidase precipitated two in vitro translation products from RNA isolated from ethylene-treated but not from control cucumber seedlings. This indicates that the increase in 33-kilodalton peroxidase activity represents de novo protein synthesis. Both forms of peroxidase degraded chlorophyll in vitro, which is consistent with the hypothesis that peroxidases have catabolic or scavenging functions in senescent tissues.