An extremely energetic cosmic ray observed by a surface detector array.

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle's energy as [Formula: see text] (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics.

Fibre type-specific expression patterns of myosin heavy chain genes in adult torafugu Takifugu rubripes muscles.

Comprehensive in silico studies, based on the total fugu genome database, which was the first to appear in fish, revealed that torafugu Takifugu rubripes contains 20 sarcomeric myosin heavy chain (MYH) genes (MYH genes) (Ikeda et al., 2007). The present study was undertaken to identify MYH genes that would be expressed in adult muscles. In total, seven MYH genes were found by screening cDNA clone libraries constructed from fast, slow and cardiac muscles. Three MYH genes, fast-type MYH(M86-1), slow-type MYH(M8248) and slow/cardiac-type MYH(M880), were cloned exclusively from fast, slow and cardiac muscles, respectively. Northern blot hybridization substantiated their specific expression, with the exception of MYH(M880). In contrast, transcripts of fast-type MYH(M2528-1) and MYH(M1034) were found in both fast and slow muscles as revealed by cDNA clone library and northern blot techniques. This result was supported by in situ hybridization analysis using specific RNA probes, where transcripts of fast-type MYH(M2528-1) were expressed in fast fibres with small diameters as well as in fibres of superficial slow muscle with large diameters adjacent to fast muscle. Transcripts of fast-type MYH(M86-1) were expressed in all fast fibres with different diameters, whereas transcripts of slow-type MYH(M8248) were restricted to fibres with small diameters located in a superficial part of slow muscle. Interestingly, histochemical analyses showed that fast fibres with small diameters and slow fibres with large diameters both contained acid-stable myofibrillar ATPase, suggesting that these fibres have similar functions, possibly in the generation of muscle fibres irrespective of their fibre types.

Axillary lymphadenectomy for breast cancer without axillary drainage.

OBJECTIVE: To evaluate axillary lymph node dissection done without closed drainage in conjunction with breast conservation cancer surgery. DESIGN: Prospective clinical study. SETTING: Two university hospitals. PATIENTS: Eighty-one women undergoing wide local excision of breast cancer with simultaneous or subsequent axillary lymph node dissection. INTERVENTIONS: No axillary drain was placed following axillary lymphadenectomy. MAIN OUTCOME MEASURES: The development and resorption of axillary seroma fluid as measured by clinical aspiration and serial sonographic examination. RESULTS: Thirty-four (42%) of the 81 women required axillary seroma aspiration even though axillary fluid was present in 92% (22/24) of those studied sonographically. The seromas accumulated over the first 2 weeks following axillary dissection and resorbed over the next 2 weeks, as assessed by both clinical and sonographic examination. The complication rate was 2% (2/81). The surgery was performed safely on an outpatient or short-stay basis in 99% (80/81) of patients. All patients except one were discharged within 23 hours of surgery, and 56 patients were discharged directly after anesthesia. CONCLUSION: Axillary lymph node dissection done in conjunction with breast conservation surgery can be performed in an ambulatory or short-stay setting without axillary drainage. Postoperative seromas will resolve within 1 month, and fewer than half will require aspiration. Lymphadenectomy without drainage reduces morbidity and allows the patient greater personal comfort.

Radiofrequency ablation of breast cancer: first report of an emerging technology.

HYPOTHESIS: Radiofrequency (RF) energy applied to breast cancers will result in cancer cell death. DESIGN: Prospective nonrandomized interventional trial. SETTING: A university hospital tertiary care center. PATIENTS: Five women with locally advanced invasive breast cancer, aged 38 to 66 years, who were undergoing surgical resection of their tumor. One patient underwent preoperative chemotherapy and radiation therapy, 3 patients received preoperative chemotherapy, and 1 had no preoperative therapy. All patients completed the study. INTERVENTIONS: While patients were under general anesthesia and just before surgical resection, a 15-gauge insulated multiple-needle electrode was inserted into the tumor under sonographic guidance. Radiofrequency energy was applied at a low power by a preset protocol for a period of up to 30 minutes. Only a portion of the tumor was treated to evaluate the zone of RF ablation and the margin between ablated and nonablated tissue. Immediately after RF ablation, the tumor was surgically resected (4 mastectomies, 1 lumpectomy). Pathologic analysis included hematoxylin-eosin staining and enzyme histochemical analysis of cell viability with nicotinamide adenine dinucleotide-diaphorase (NADH-diaphorase) staining of snap-frozen tissue to assess immediate cell death. MAIN OUTCOME MEASURE: Cancer cell death as visualized on hematoxylin-eosin-stained paraffin section and NADH-diaphorase cell viability stains. RESULTS: There was evidence of cell death in all patients. Hematoxylin-eosin staining showed complete cell death in 2 patients. In 3 patients there was a heterogeneous pattern of necrotic and normal-appearing cells within the ablated tissue. The ablated zone extended around the RF electrode for a diameter of 0.8 to 1.8 cm. NADH-diaphorase cell viability stains of the ablated tissue showed complete cell death in 4 patients. The fifth patient had a single focus of viable cells (<1 mm) partially lining a cyst. There were no perioperative complications related to RF ablation. CONCLUSIONS: Intraoperative RF ablation results in invasive breast cancer cell death. Based on this initial report of the use of RF ablation in breast cancer, this technique merits further investigation as a percutaneous minimally invasive modality for the local treatment of breast cancer.

Emergence of Streptococcus faecalis isolates with high-level resistance to multiple aminocyclitol aminoglycosides.

Isolates of Streptococcus faecalis were occasionally found to be resistant to gentamicin concentrations of 500 micrograms/ml in a microdilution tray. Additional tests were performed with 28 such isolates. They all demonstrated high-level resistance (minimum inhibitory concentration greater than 2000 micrograms/ml) to gentamicin, kanamycin, sisomicin, streptomycin, and tobramycin. This high-level aminoglycoside resistance was associated with total resistance to in vitro synergism when each aminoglycoside was combined with ampicillin. In addition to ampicillin-aminoglycoside combinations, ampicillin-vancomycin, ampicillin-rifampin, rifampin-vancomycin, and vancomycin-gentamicin combinations were also tested; all failed to exhibit an in vitro synergistic-bactericidal effect against these enterococci. The emergence of enterococci with high-level resistance to multiple aminoglycosides in this clinical population is a source of grave concern with obvious therapeutic implications in situations such as endocarditis, where an in vitro bactericidal effect is thought to be necessary for a cure. No drug or combination of drugs was found to be bactericidal for these isolates. It is suspected that similar isolates of group D streptococci with high-level resistance to gentamicin may emerge in other institutions but go unrecognized. Surveillance by others for identifying this newly emerging pathogen carrying multiple resistance and a continued search for a satisfactory chemotherapeutic agent(s) are encouraged.

Evaluation of a brief cognitive-behavioral program for the prevention of chronic PTSD in recent assault victims.

The efficacy of a brief prevention program (BP) aimed at arresting the development of chronic PTSD was examined with 10 recent female victims of sexual and nonsexual assault who received 4 sessions of a cognitive-behavioral program shortly after the assault. Their PTSD and depression severity was compared with that of 10 matched recent female assault victims who received repeated assessments of their trauma-related psychopathology (assessment control; AC). The BP program consisted of education about common reactions to assault and cognitive-behavioral procedures. Two months postassault, victims who received the BP program had significantly less severe PTSD symptoms than victims in the control condition; 10% of the former group met criteria for PTSD versus 70% of the latter group. Five and a half months postassault, victims in the BP group were significantly less depressed than victims in the AC group and had significantly less severe reexperiencing symptoms.

Image compression in digital mammography: effects on computerized detection of subtle microcalcifications.

Our previous receiver operating characteristic (ROC) study indicated that the detection accuracy of microcalcifications by radiologists is significantly reduced if mammograms are digitized at 0.1 mm x 0.1 mm. Our recent study also showed that detection accuracy by computer decreases as the pixel size increases from 0.035 mm x 0.035 mm. It is evident that very large matrix sizes have to be used for digitizing mammograms in order to preserve the information in the image. Efficient compression techniques will be needed to facilitate communication and archiving of digital mammograms. In this study, we evaluated two compression techniques: full frame discrete cosine transform (DCT) with entropy coding and Laplacian pyramid hierarchical coding (LPHC). The dependence of their efficiency on the compression parameters was investigated. The techniques were compared in terms of the trade-off between the bit rate and the detection accuracy of subtle microcalcifications by an automated detection algorithm. The mean-square errors in the reconstructed images were determined and the visual quality of the error images was examined. It was found that with the LPHC method, the highest compression ratio achieved without a significant degradation in the detectability was 3.6:1. The full frame DCT method with entropy coding provided a higher compression efficiency of 9.6:1 at comparable detection accuracy. The mean-square errors did not correlate with the detection accuracy of the microcalcifications. This study demonstrated the importance of determining the quality of the decompressed images by the specific requirements of the task for which the decompressed images are to be used. Further investigation is needed for selection of optimal compression technique for digital mammograms.

Digitization requirements in mammography: effects on computer-aided detection of microcalcifications.

We have developed a computerized method for detection of microcalcifications on digitized mammograms. The program has achieved an accuracy that can detect subtle microcalcifications which may potentially be missed by radiologists. In this study, we evaluated the dependence of the detection accuracy on the pixel size and pixel depth of the digitized mammograms. The mammograms were digitized with a laser film scanner at a pixel size of 0.035 mm x0.035 mm and 12-bit gray levels. Digitization with larger pixel sizes or fewer number of bits was simulated by averaging adjacent pixels or by eliminating the least significant bits, respectively. The SNR enhancement filter and the signal-extraction criteria in the computer program were adjusted to maximize the accuracy of signal detection for each pixel size. The overall detection accuracy was compared using the free response receiver operating characteristic curves. The results indicate that the detection accuracy decreases significantly as the pixel size increases from 0.035 mm x 0.035 mm to 0.07 mm x 0.07 mm (P < 0.007) and from 0.07 mm x 0.07 mm to 0.105 mm x 0.105 mm (P < 0.002). The detection accuracy is essentially independent of pixel depth from 12 to 9 bits and decreases significantly (P < 0.003) from 9 to 8 bits; a rapid decrease is observed as the pixel depth decreases further from 8 to 7 bits (P < 0.03) or from 7 to 6 bits (P < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Society of Breast Imaging residency and fellowship training curriculum.

A recently developed Society of Breast Imaging curriculum for residency training is intended to provide guidance to residents and their mentors, and to practicing radiologists who want to keep up to date in screening, diagnosis, and interventional procedures. The curriculum contains lists of key concepts in 14 subject areas: epidemiology; anatomy; pathology, and physiology; equipment and technique; quality control; interpretation; problem-solving mammography; ultrasound; interventional procedures; reporting and medicolegal aspects; screening; MR imaging; therapeutic considerations; and patient management principles. The curriculum also makes recommendations about residency training, including the number of examinations the resident should interpret, and the time the resident should spend in breast imaging. Recommendations for fellowship training are also discussed.

Interactive MR-guided, 14-gauge core-needle biopsy of enhancing lesions in a breast phantom mode.

RATIONALE AND OBJECTIVES: The authors attempted to determine the accuracy of magnetic resonance (MR) imaging-guided core-needle biopsy performed with a titanium biopsy needle in a breast phantom. MATERIALS AND METHODS: Eight 6-7-mm lesions were created at random positions in a lard breast phantom. Each 0.2-mL lesion contained 0.118 mg of gadopentetate dimeglumine, 0.0025 mL of methylene blue dye, and 23.8 mg of gelatin. Rapid fast spin-echo MR imaging was used to guide placement of a 14-gauge titanium core-biopsy needle. A 1.5-T MR imager was used with an open-platform phased-array breast coil. RESULTS: Visualization of blue dye in core specimens confirmed successful biopsy in 16 of 16 attempts. One (n = 13) or two (n = 3) passes through the "skin" of the phantom were necessary for biopsy. The needle trajectory was adjusted less than three times for each pass through the "skin" in 15 of 16 biopsies. Cores that contained lesion material were obtained in the first sample in 15 of 16 biopsies. On T1-weighted images, needles cast 7-mm-diameter artifacts. CONCLUSION: MR imaging can be used accurately to guide core-needle biopsy of 6-7-mm lesions in a breast phantom.

Total syntheses of bellenamine and its isomers.

The total synthesis of bellenamine was achieved by a modified CURTIUS procedure starting with D-beta-lysine. Bis(N-benzyloxycarbonyl)-D-beta-lysylglycine was converted to tris(N-benzyloxycarbonyl)bellenamine which was catalytically hydrogenated to yield bellenamine. D-beta-Lysine was synthesized from D-ornithine by the ARNDT-EISTERT homologation sequence. Three isomers, L-beta-lysyl, D- and L-lysyl congeners synthesized by a similar method, showed no antibacterial activities.

Synthesis of demethyl derivatives of istamycin A.

4-N,6'-N,3-O-Tridemethylistamycin A0 (9) and 6'N,3-O-didemethylistamycin A0 (15) were synthesized from 3,2',6'-tri-N-benzyloxycarbonyl-3',4'-dideoxyneamine 1,6-carbamate (1) through an aziridine derivative 6 by an analogous procedure employed in the total synthesis of istamycin A0 (19). Acylation of 15 with glycine at the 4-methylamino group gave 6'-N,3-O-didemethylistamycin A (18) having interesting activities especially against pseudomonas, but 4-N,6'-N,3-O-tridemethylistamycin A (12) derived from 9 showed only weak activity. Therefore, the 4-N-methyl group of istamycin A (20) is essential for the antimicrobial activity.

Bagougeramines A and B, new nucleoside antibiotics produced by a strain of Bacillus circulans. II. Physico-chemical properties and structure determination.

Bagougeramines A and B obtained as sulfates were soluble in water and positive to Sakaguchi, chlorine-tolidine and ninhydrin color reactions. Their structures were determined by acid hydrolysis and spectroscopic analysis. Structurally they were closely related to gougerotin and they contained the guanidino-D-alanine instead of the serine residue in gougerotin. Bagougeramine B had the spermidine instead of the 6'-NH2 in structure of bagougeramine A.

Amino acid analogs of benanomicin A through desalaninebenanomicin A.

Desalaninebenanomicin A has been synthesized in good yield by the cleavage of the amido bond of benanomicin A using MEERWEIN's reagent. This is a useful intermediate to prepare amino acid analogs of benanomicin A. MEERWEIN's reagent reacts with totally protected benanomicin A to give a stable imino ether. After deprotection, the imino ether is treated with aqueous acetone at reflux to afford a methyl ester of desalaninebenanomicin A. Desalaninebenanomicin A was coupled with a variety of amino acids by the active ester method to afford new benanomicin analogs.

Altemicidin, a new acaricidal and antitumor substance. I. Taxonomy, fermentation, isolation and physico-chemical and biological properties.

Screening of new insecticidal and acaricidal antibiotics was carried out with reference to anti-brine shrimp activity from actinomycete strains isolated from marine environments. Of 200 actinomycete isolates, one isolate was found to produce a new substance, altemicidin. The strain was isolated from sea mud collected at Gamo, Miyagi Prefecture, Japan, and identified as Streptomyces sioyaensis SA-1758. Altemicidin was purified by Diaion CHP-20P and Sephadex LH-20 column chromatographies. The molecular formula was determined as C13H20N4O7S by elemental analysis, MS and 13C NMR spectrum. Altemicidin showed not only acaricidal activity but also antitumor activity. The compound showed no antimicrobial activity except the inhibitory activity to Xanthomonas strains.

Synthesis and activity of 3-(isoxazolin-5-yl)- and 3-(isoxazol-4-yl)cephalosporins.

The 1,3-dipolar cycloaddition of nitrile oxide with 3-vinylcephalosporin provided diastereomeric isomers of 3-(isoxazolin-5-yl)cephalosporin. Cycloaddition of nitrile oxide with 3-(dimethylamino-vinyl)cephalosporin gave 3-(isoxazol-4-yl)cephalosporin. These semisynthetic cephalosporins with an aminothiazole in the C-7 side chain showed moderate antibacterial activities.

Synthesis and activity of potent 3-(isoxazolidin-5-yl)- and 3-(isoxazolidinium-5-yl)cephalosporins.

The syntheses and in vitro antibacterial activities of 3-(isoxazolidin-5-yl)- and 3-(isoxazolidinium-5-yl)cephalosporins are described. 1,3-Dipolar cycloaddition of 3-vinylcephalosporin with nitrone gave diastereomeric isomers of 3-(isoxazolidin-5-yl)cephalosporin. The antibacterial activities of 3'-(S)-isomers were superior to those of 3'-(R)-isomers. The quaternarization of isoxazolidine ring increased the antibacterial activity. Among them, compound 10b with a hydroxyimino group in the C-7 side chain showed potent activities against staphylococci and compound 10f with an N-hydroxypyridone exhibited an excellent antipseudomonal activity.

A synthetic approach to benanomicin A. 2. Synthesis of the substituted 5,6-dihydrobenzo[a]naphthacenequinone.

The key intermediate tri-substituted alpha-tetralone (8) has been synthesized, either via tandem Michael addition-Dieckmann condensation reaction between dienolate and methyl crotonate in a low yield or via Barton's radical decarboxylation of diester (9) without 4-dimethylaminopyridine in 75% yield, and applied to the synthesis of the substituted 5,6-dihydrobenzo[a]naphthacenequinone.

A synthetic approach to benanomicin A. 1. Synthesis of 5,6-dihydrobenzo[a]naphthacenequinone.

5,6-Dihydrobenzo[a]naphthacenequinone has been constructed by Diels-Alder reaction of an outer-ring diene with a naphthoquinone regioselectively. Similarly, the 14-hydroxy-5,6-dihydrobenzo[a]naphthacenequinone (13) has also been synthesized via the reaction of vinylketene acetal (11) with naphthoquinone.