Is there a role for abdominal computed tomographic scans in appendicitis?

OBJECTIVE: To better define the effectiveness of abdominal computed tomographic scanning (ACTS) in adult patients with suspected appendicitis. DESIGN: Retrospective analysis. SETTING: A community teaching hospital. PATIENTS: Ninety-seven patients with appendicitis in the differential diagnosis, whose clinical findings were insufficient to perform surgery or to discharge from the hospital, during a 14-month period. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Accuracy of ACTS, rate of appendectomies that show no appendicitis (negative appendectomy rate), and frequency of ACTS as a definitive diagnostic test. RESULTS: Forty-nine of the 50 patients with appendicitis were correctly diagnosed by ACTS. Forty-three of the 47 patients without appendicitis were correctly diagnosed by ACTS. Positive predictive value was 92%, negative predictive value was 98%, and accuracy was 96%. The ACTS group had a negative appendectomy rate of 5.8% (3/52), lower than the hospital rate of 14% for the preceding 3 years. The ACTS established an alternative diagnosis in 16 patients, allowed 10 other patients to be discharged early or not admitted, and was the critical diagnostic test in 30 of the patients with appendicitis. Therefore, the ACTS played a definitive role in the treatment of 56 (57.7%) of the 97 patients. CONCLUSIONS: The ACTS was an accurate test in the diagnosis of appendicitis and was of significant benefit in 57.7% of the patients studied. However, it was difficult to predict which patients were most likely to benefit. Expanded selective use of ACTS for patients with clinically indeterminate appendicitis may result in a lower negative appendectomy rate and fewer patient admissions for observation.     

Response patterns and force relations of monkey spinal interneurons during active wrist movement

The activity of C6-T1 spinal cord neurons was recorded in three macaques while they generated isometric wrist flexion and extension torques in visually guided step-tracking tasks. Electromyographic activity (EMG) was recorded in /=3.5 ms from the trigger. Synchrony interneurons (Sy-INs) were non-PreM-Ins that had spike-related features with latencies <3.5 ms in at least one muscle. Unidentified interneurons (U-INs) showed no features in any of the STAs. A total of 572 task-related spinal neurons were studied; 29 cells were MNs, 97 PreM-INs, 32 Sy-INs, and 414 U-INs. MNs were activated predominantly in a tonic fashion during the ramp-and-hold torques and were active in one direction only. The most common response pattern for interneurons, irrespective of their class, was phasic-tonic activity, followed by purely tonic and purely phasic activity. Most interneurons (77%) were bidirectionally active in both flexion and extension. For all classes of interneurons, units with phasic response components tended to be activated first, before torque onset, followed by tonic units. The onset times of PreM-INs relative to onsets of their target muscles were distributed broadly, with a mean of -25 +/- 128 (SD) ms. For most neurons with tonic response components (all MNs, 71% of PreM-INs, 67% of Sy-INs, and 84% of U-INs), activity during the hold period was correlated significantly with the magnitude of static torque exerted by the monkey. The rate-torque regressions generally had positive slopes with higher mean slopes for extension than for flexion. The phasic response components were correlated significantly with rate of change of torque for a smaller percentage of tested PreM-Ins (50%), Sy-INs (83%), and U-INs (77%). In contrast to other premotor neurons [corticomotoneuronal (CM), rubromotoneuronal (RM), and dorsal root ganglion (DRG) afferents] previously characterized under similar conditions, a larger proportion of the spinal PreM-INs were activated after onset of their target muscles, probably reflecting a larger proportion of PreM-INs driven by peripheral input. The rate-torque slopes of PreM-INs tended to be less steep than those of CM and RM cells. Unlike the CM and DRG PreM afferents, which were activated unidirectionally, most spinal PreM-INs showed bidirectional activity, like RM cells.     

Granulocytic sarcoma with mediastinal involvement

BACKGROUND: Granulocytic sarcoma is more frequent in adults; it can be a tumoral localization of acute non-lymphoblastic leukemia. This report describes an infantile case revealing an acute myeloid leukemia. CASE REPORT: A 14 month-old girl was admitted because of enlarged bilateral cervical lymph nodes. They had increased in volume over the past month and were accompanied by fever and anorexia. The liver and spleen were moderately enlarged. Hematologic data were: Hb = 7.5 g%; leucocytes = 14,900/mm3; platelets = 614,000/mm3. There were no abnormal cells. X-rays and MRI showed a mediastinal mass. Bone scintigraphy was normal but the myelogram showed a few atypical cells that were also seen in a biopsy of the cervical lymph node. Electron microscopic examination of these cells showed that they were myeloid in origin. This was confirmed by immunohistochemistry. The cytogenetic examination showed many chromosomal abnormalities in the lymph node and myelogram. The child is now recovered after nine months of chemotherapy. CONCLUSION: Diagnosis of acute myeloblastic leukemia in children is difficult when it is revealed by granulocytic sarcoma without major infiltration of bone marrow. The clinical presentation as a mediastinal mass is rare. The cytogenetic study was determinant for diagnosis.     

Interstitial laser prostatectomy

Despite numerous studies on the recurrence rate and risk factors following operations for Crohn's disease, unequivocal evidence on how to prevent recurrence non-medically and on the specific risks is lacking. Just two recommendations are supported by sufficient data: Do not perform radical resections with wide margins of safety and try to prevent the patient from smoking. Further studies are needed to delineate high risk subgroups for specific pharmacological interventions postoperatively.     

Characterization of PLZT Films Deposited by Spray Pyrolysis

Spray pyrolysis was used to prepare films of PLZT ceramics, a class of electrooptic materials that find applications in integrated optics devices. The films were prepared by spraying an aqueous solution of mainly nitrate salts of the desired cations onto oriented silicon and magnesia substrates. After drying, the solid deposit was thermally decomposed to yield the mixture of the desired oxides. The surface morphology of the prepared thin films was examined by optical and scanning electron microscopy and the presence of crystalline phases was identified by X-ray powder diffraction. Compositional homogeneity was determined by energy-dispersive X-ray microanalysis.     

Organization of prose materials: Stimulus, storage, and retrieval.

Gave prose passages which were organized around names of countries or attributes or were randomly organized to 180 college students. Ss were required to recall the material by name, attribute, or free recall. One-half of each group was instructed about recall requirements prior to reading the passages. Recall scores and clustering indices led to the conclusion that name and attribute input organization is superior to random organization. Results provide evidence suggesting basic processing differences between the Ss in the different organization groups. (French summary) (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Docosahexaenoic Acid is More Stable to Oxidation when Located at the sn-2 Position of Triacylglycerol Compared to sn-1(3)

Regio-isomeric effects on the oxidative stability of triacylglycerols (TAG) containing docosahexaenoic acid (DHA) were investigated using two pairs of regio-isomerically pure TAG, namely 1,3-dihexadecanoyl-2-(4,7,10,13,16,19-docosahexaenoyl)glycerol (PDP)/1,2-dihexadecanoyl-3-(4,7,10,13,16,19-docosahexaenoyl)glycerol (PPD) and 1,3-dioctadecenoyl-2-(4,7,10,13,16,19-docosahexaenoyl)glycerol (ODO)/1,2-dioctadecenoyl-3-(4,7,10,13,16,19-docosahexaenoyl)glycerol (OOD) where P, O, and D represent palmitic acid, oleic acid, and DHA respectively. Each pair of regio-isomers was subjected to accelerated auto-oxidation (at 40 or 50 °C inside a dark oven). In each case, the TAG oxidized more slowly when DHA was located at the sn-2 position (PDP and ODO) compared to the sn-1(3) position (PPD and OOD), as evidenced by slower development of peroxide value, slower depletion of DHA, and slower generation of secondary oxidation products propanal and trans, trans-2,4-heptadienal. The positional effect on auto-oxidation was more pronounced when DHA occurred in combination with oleic acid than with palmitic acid.     

Radiolabeled 6-(2, 3-Dichlorophenyl)-N4-methylpyrimidine-2, 4-diamine (TH287): A Potential Radiotracer for Measuring and Imaging MTH1

MTH1 (MutT homolog 1) or NUDT1 (Nudix Hydrolase 1), also known as oxidized purine nucleoside triphosphatase, has potential as a biomarker for monitoring cancer progression and quantifying target engagement for relevant therapies. In this study, we validate one MTH1 inhibitor TH287 as a PET MTH1 radiotracer. TH287 was radiolabeled with tritium and the binding of [³H]TH287 to MTH1 was evaluated in live glioblastoma cells (U251MG) through saturation and competitive binding assays, together with in vitro enzymatic assays. Furthermore, TH287 was radiolabeled with carbon-11 for in vivo microPET studies. Saturation binding assays show that [³H]TH287 has a dissociation constant (K_d) of 1.97 ± 0.18 nM, B_max of 2676 ± 122 fmol/mg protein for U251MG cells, and n_H of 0.98 ± 0.02. Competitive binding assays show that TH287 (K_i: 3.04 ± 0.14 nM) has a higher affinity for MTH1 in U251MG cells compared to another well studied MTH1 inhibitor: (S)-crizotinib (K_i: 153.90 ± 20.48 nM). In vitro enzymatic assays show that TH287 has an IC₅₀ of 2.2 nM in inhibiting MTH1 hydrolase activity and a K_i of 1.3 nM from kinetics assays, these results are consistent with our radioligand binding assays. Furthermore, MicroPET imaging shows that [¹¹C]TH287 gets into the brain with rapid clearance from the brain, kidney, and heart. The results presented here indicate that radiolabeled TH287 has favorable properties to be a useful tool for measuring MTH1 in vitro and for further evaluation for in vivo PET imaging MTH1 of brain tumors and other central nervous system disorders.     

Kinetics of hydration-dehydration reactions considered as solid transformations

A mechanism is proposed for the dehydration-rehydration process in solid inorganic salts, and model rate equations are derived and applied to the observed behavior of potassium carbonate. Quantitative expressions for the effect of pressure on the reaction rates are derived using basic principles from nucleation and heterogeneous phase transformation theory. Model equation predictions agree with experimental dehydration and rehydration rate data at all but extreme pressures. The basic rate equation is also used to interpret the data of Eckhardt and Flanagan (1964) for the effect of pressure on the dehydration of manganous formate dihydrate. The mechanism on which the model equations are based is also consistent with the observed effects of cycling and of high temperature pretreatment on the K₂CO₃ rehydration rate.