Effect of anatomic distribution of pulmonary emboli on interobserver agreement in the interpretation of pulmonary angiography

OBJECTIVE: This study examines the anatomic distribution of emboli on pulmonary angiography and attempts to determine the relationship of vessel size to interobserver agreement, two factors having important implications in comparing pulmonary angiography with cross-sectional imaging for pulmonary embolism. MATERIALS AND METHODS: One hundred twenty-five consecutive pulmonary angiograms were reviewed retrospectively by three interventional radiologists. Initial interpretations were recorded and compared to determine interobserver agreement on a per-patient and per-embolus basis. Discordant interpretations were reviewed by all radiologists for a consensus interpretation. RESULTS: Unanimous per-patient agreement occurred in 91% (114/125) of initial interpretations. The largest artery containing acute pulmonary embolism was segmental or larger in 24 patients (83% of patients with acute positive findings, 19% of all patients) and subsegmental in only five patients (17% and 4%, respectively). On a per-patient basis, initial interobserver agreement averaged 45% and unanimous consensus agreement was achieved for 79% of patients having isolated subsegmental pulmonary embolism. Consensus readings altered initial per-patient interpretations for 30% of patients having only subsegmental pulmonary embolism; per-embolus interpretations were altered for 37% of all subsegmental emboli. CONCLUSION: Subsegmental emboli occurring as isolated findings are relatively rare. Approximately one third of subsegmental emboli and one third of patients having isolated subsegmental emboli may be initially misdiagnosed on pulmonary angiography. Objections to cross-sectional imaging for pulmonary embolism based on the inability to detect subsegmental pulmonary embolism when compared with pulmonary angiography should be reexamined with this data in mind.     

Acute hepatic allograft rejection: incidence, risk factors, and impact on outcome

Hepatic allograft rejection remains an important problem following liver transplantation, and, indeed, complications related to the administration of immunosuppressive therapy remain a predominant cause of posttransplantation morbidity and mortality. The Liver Transplantation Database (LTD) was used to study a cohort of 762 consecutive adult liver transplantation recipients and determined the incidence, timing, and risk factors for acute rejection. We also evaluated the impact of histological severity of rejection on the need for additional immunosuppressive therapy and on patient and graft survival. Four hundred ninety (64%) of the 762 adult liver transplantation recipients developed at least one episode of rejection during a median follow-up period of 1,042 days (range, 336-1,896 days), most of which occurred during the first 6 weeks after transplantation. Multivariate analysis revealed that recipient age, serum creatinine, aspartate transaminase (AST) level, presence of edema, donor/recipient HLA-DR mismatch, cold ischemic time, and donor age were independently associated with the time to acute rejection. An interesting observation was that the histological severity of rejection was an important prognosticator: the use of antilymphocyte preparations was higher, and the time to death or retransplantation was shorter, for patients with severe rejection. Findings from this study will assist in decision-making for the use of immunosuppressive regimens and call into question whether complete elimination of all rejection or alloreactivity is a desirable goal in liver transplantation.     

Translation of some maize small heat shock proteins is initiated from internal in-frame AUGs

Etiolated maize radicles (inbred Oh43) subjected to a brief heat shock synthesize a family of small heat shock proteins (approximately 18 kD) that is composed of at least 12 members. We previously described the cDNA-derived sequence of three maize shsp mRNAs (cMHSP18-1, cMHSP18-3, and cMHSP18-9). In this report, we demonstrate that the mRNA transcribed in vitro from one of these cDNAs (cMHSP18-9) is responsible for the synthesis of three members of the shsp family, and we suggest that cMHSP18-3 may be responsible for the synthesis of three additional members and cMHSP18-1 for the synthesis of two other members of this family. The fact that these genes do not contain introns, coupled with the observations reported herein, suggest that maize may have established another method of using a single gene to produce a number of different proteins.     

Determinants of clinical decision making in primary care: opinion of physicians

The in vivo genotoxic activities in mouse skin of the dimethyl sulphoxide (DMSO) extracts of a range of oil products [residual aromatic extract; untreated heavy paraffinic distillate aromatic extract; mildly refined light naphthenic base oil; bitumen (vacuum residue); high viscosity index base oil obtained by catalytic hydrogenation] were evaluated by 32P-postlabelling DNA analysis. The results of quantitative 32P-postlabelling analyses of epidermal DNA from mice treated with the DMSO extracts showed linear relationships with the total polycyclic aromatic compound (PAC) contents, determined by the Institute of Petroleum method IP 346 and also the 3-6 ring PAC contents, measured by on-line liquid-liquid extraction using flow injection analysis. The 32P-postlabelling data also showed a linear relationship with the mutagenicity indices of these oil products determined in S. typhimurium TA98 using the modified Ames Salmonella microsome test. The in vivo genotoxicity of the DMSO extracts from the oil products was low, judged by 32P-postlabelling analysis of DNA adducts measured in epidermal DNA of treated mouse skin, and ranging from 2 to 723 attomole/microg DNA per mg oil product. The in vivo 32P-postlabelling data from this study are consistent with these materials expressing low genotoxicity in mouse skin in vivo. The DMSO extraction procedure coupled with 32P-postlabelling DNA analysis is useful for ranking the relative genotoxic potency in vivo of a wide range of oil products. In general the trend observed is similar to rankings based on physicochemical measurements of total PAC contents or 3 6 ring PAC contents of the oil products.     

The salubrious effects of ascorbic acid on cyclophosphamide instigated lipid abnormalities in fibrosarcoma bearing rats

A new class of silica gel-bound fluorene phases is described. The compounds are synthesized via reaction of fluorenyl lithium with omega-alkenyl bromides leading to 9-(5'-hexenyl)-9H- and 9-(9'-decenyl)-9H-fluorene (1 and 2), followed by hydrosilation reactions with different hydrosilanes. The resulting omega-functionalized silylalkyl fluorenes 3a(T0), 3b(T0), 4a(T0), 4b(T0) and 4c(M0) (Scheme 1) react with surface silanol groups of silica gel to generate the new fluorene phases 3a(Tn)(Qm)y, 3b(Tn)(Qm)y, 4a(Tn)(Qm)y, 4b(Tn)(Qm)y and 4c(M1)(Qm)y. The phases are characterized by employing 1H, 13C and 29Si solid-state nuclear magnetic resonance spectroscopy. Their applicability in high-performance liquid chromatography is proved by the Sander and Wise test (SRM 869). In contrast to conventional n-alkyl phases, pi-pi interactions are additionally involved in the separation process and, therefore, the retention times of the polycyclic aromatic hydrocarbons sample molecules depend on the ligand densities of the applied fluorene phases.     

Randomized trial of blunt-tipped versus cutting needles to reduce glove puncture during mass closure of the abdomen

Eighty-five consecutive patients were randomized to undergo mass closure of the abdomen with no. 1 polydioxanone mounted on either a blunt-tipped (n = 46) or cutting (n = 39) needle. Gloves were changed before closure and tested for perforation afterwards using standard air or water techniques. Fourteen pairs of gloves were punctured when using a cutting needle, and three pairs when a blunt-tipped needle was used. The majority of punctures were to the non-dominant glove. The surgeon was aware of the puncture in eight of the 14 instances involving a sharp needle and in one of the three involving a blunt-tipped needle. Blunt-tipped needles, while not eliminating the risk, significantly reduced the incidence of surgical glove puncture (P < 0.001, Fisher's exact test). The use of cutting needles for abdominal closure should be abandoned.     

A phase I clinical and pharmacokinetic study of the angiogenesis inhibitor, tecogalan sodium

BACKGROUND: Tecogalan sodium is an angiogenesis inhibitor isolated from a sulfated polysaccharide produced by the bacterium Arthrobacter. The antiangiogenic effect of tecogalan sodium is thought to be mediated by the inhibition of binding of basic fibroblast growth factor to cellular receptors. PATIENTS AND METHODS: A phase I study was conducted in thirty-three patients with refractory malignancies, including AIDS-associated Kaposi's sarcoma. Patients received a single i.v. infusion every three weeks with the infusion duration ranging from one to twenty-four hours. Seven different dosage levels were studied (125, 185, 240, 300, 390, 445, and 500 mg/m2). RESULTS: The primary dose-limiting toxicity was prolongation of the activated partial thromboplastin time with peak times being between 1.0-4.0 times the upper limit of normal. This toxicity was ameliorated at a given dose level by prolonging the infusion time. Other common toxicities included fever (40%) and rigors (31%) which were well controlled with acetominophen and meperidine. The serum half-life of tecogalan sodium was between 1-1.5 hours and < 25% of unchanged drug was excreted in the urine. CONCLUSIONS: The recommended phase II dose of tecogalan sodium on this schedule is 390 mg/m2 over 24 hours. Other schedules including continuous administration should be investigated to maximize the efficacy of this novel angiogenesis inhibitor.     

Automated reasoning system in histopathologic diagnosis and prognosis of prostate cancer and its precursors

OBJECTIVE: This article presents the rationale and options offered to diagnostic and prognostic decision support systems for prostate pathology by automated reasoning capabilities. METHODS: The symbolic information used in diagnostic decision-making is systematically ordered, compared, numerically assessed in its probability, and combined such that a conclusion can be drawn. The framework for the processing of such symbolic information may be an expert system, an inference network or a case-based reasoning system. Automated reasoning is implemented by the use of a rule base and information flow control modules. RESULTS: Automated reasoning allows decision support systems to follow highly adaptive decision sequences, capable of handling contradictory evidence, exceptions in diagnostic clue expression, and nonmonotonic decision-making. CONCLUSIONS: Automated reasoning capability in diagnostic and prognostic decision support systems allows highly flexible decision development, very close to human decision procedures.