Alternating repetition time balanced steady state free precession.

A novel balanced SSFP technique for the separation or suppression of different resonance frequencies (e.g., fat suppression) is presented. The method is based on applying two alternating and different repetition times, TR(1) and TR(2). This RF scheme manipulates the sensitivity of balanced SSFP to off-resonance effects by a modification of the frequency response profile. Starting from a general approach, an optimally broadened stopband within the frequency response function is designed. This is achieved with a TR(2) being one third of TR(1) and an RF-pulse phase increment of 90 degrees . With this approach TR(2) is too short ( approximately 1 ms) to switch imaging gradients and is only used to change the frequency sensitivity. Without a significant change of the spectral position of the stopband, TR(1) can be varied over a range of values ( approximately 2.5-4.5 ms) while TR(2) and phase cycling is kept constant. On-resonance spins show a magnetization behavior similar to balanced SSFP, but with maximal magnetization at flip angles about 10 degrees lower than in balanced SSFP. The total scan time is increased by about 30% compared to conventional balanced SSFP. The new technique was applied on phantoms and volunteers to produce rapid, fat suppressed images.     

203Pb-labeled alpha-melanocyte-stimulating hormone peptide as an imaging probe for melanoma detection.

Peptide-targeted alpha-therapy with 7.4 MBq of (212)Pb-[1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-ReO-[Cys(3,4,10),d-Phe(7),Arg(11)]alpha-MSH(3-13) ((212)Pb-DOTA-Re(Arg(11))CCMSH) cured 45% of B16/F1 murine melanoma-bearing C57 mice in a 120-d study, highlighting its melanoma treatment potential. However, there is a need to develop an imaging surrogate for patient-specific dosimetry and to monitor the tumor response to (212)Pb-DOTA-Re(Arg(11))CCMSH therapy. The purpose of this study was to evaluate the potential of (203)Pb-DOTA-Re(Arg(11))CCMSH as a matched-pair SPECT agent for (212)Pb-DOTA-Re(Arg(11))CCMSH. METHODS: DOTA-Re(Arg(11))CCMSH was labeled with (203)Pb in 0.5 M NH(4)OAc buffer at pH 5.4. The internalization and efflux of (203)Pb-DOTA-Re(Arg(11))CCMSH were determined in B16/F1 melanoma cells. The pharmacokinetics of (203)Pb-DOTA-Re(Arg(11))CCMSH was examined in B16/F1 melanoma-bearing C57 mice. A micro-SPECT/CT study was performed with (203)Pb-DOTA-Re(Arg(11))CCMSH in a B16/F1 melanoma-bearing C57 mouse at 2 h after injection. RESULTS: (203)Pb-DOTA-Re(Arg(11))CCMSH was easily prepared in NH(4)OAc buffer and completely separated from the excess nonradiolabeled peptide by reversed-phase high-performance liquid chromatography (RP-HPLC). (203)Pb-DOTA-Re(Arg(11))CCMSH displayed fast internalization and extended retention in B16/F1 cells. Approximately 73% of (203)Pb-DOTA-Re(Arg(11))CCMSH activity internalized after a 20-min incubation at 25 degrees C. After incubation of the cells in culture medium for 20 min, 78% of internalized activity remained in the cells. (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited a biodistribution pattern similar to that of (212)Pb-DOTA-Re(Arg(11))CCMSH in B16/F1 melanoma-bearing mice. (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited a peak tumor uptake of 12.00+/-3.20 percentage injected dose per gram (%ID/g) at 1 h after injection. The tumor uptake gradually decreased to 3.43+/-1.12 %ID/g at 48 h after injection. (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited a peak tumor-to-kidney uptake ratio of 1.53 at 2 h after injection. The absorbed doses to the tumor and kidneys were 4.32 and 4.35 Gy, respectively, per 37 MBq. Whole-body clearance of (203)Pb-DOTA-Re(Arg(11))CCMSH was fast, with approximately 89% of the injected activity cleared through the urinary system by 2 h after injection. (203)Pb showed 1.6-mm SPECT resolution, which was comparable to (99m)Tc. Melanoma lesions were visualized through SPECT/CT images of (203)Pb-DOTA-Re(Arg(11))CCMSH at 2 h after injection. CONCLUSION: (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited favorable pharmacokinetic and tumor imaging properties, highlighting its potential as a matched-pair SPECT agent for (212)Pb-DOTA-Re(Arg(11))CCMSH melanoma treatment.     

Antithyreoglobulin und Antithyroxin

Zusammenfassung Der O₂-Verbrauch von mit parenteralem Thyreoglobulin längere Zeit hindurch behandelten weißen Ratten wird stark herabgesetzt. Die Reaktionsbereitschaft solcher Tiere ist auch subcutan eingespritztem Thyroxin gegenüber vermindert, so daß der O₂-Verbrauch der Tiere nur auf Thyroxingaben von über 15 mg eine deutliche Steigerung zeigt. Meerschweinchen verhielten sich ähnlich wie die Ratten. Bei Kaninchen zeigte sich dagegen im Verlaufe der Thyreoglobulinbehandlung eine deutliche Steigerung des Stoffwechsels, nach der Thyreoglobulinbehandlung wurde der O₂-Verbrauch dieser Tiere auf Thyroxineinspritzung entsprechend erhöht. Diese an Ratten und Meerschweinchen gemachte Beobachtung dürfte ihre Erklärung darin finden, daß in diesen Versuchen das Thyreoglobulin als Antigen in serologischem Sinne wirkte, so daß ihre parenterale Verabreichung die Entstehung von gegen Thyreoglobulin und Thyroxin gerichteten Antikörpern herbeigeführt hatte. — Es ist anzunehmen, daß in diesen Versuchen das Thyreoglobulin sich als ein chemospezifisches Antigen verhielt, in dem Sinne, daß das Thyroxin neben dem Eiweißschlepper die Rolle der spezifischen Gruppe spielte, wodurch sie die Spezifizität der entstandenen Antikörper beeinflußt bzw. bestimmt hatte. Diese Deutung wird nicht so sehr in den Ergebnissen der mitgeteilten serologischen Versuche ihre Bekräftigung finden, vielmehr aber in der Tatsache, daß der thyroxinhemmende Faktor bei Ratten durch Sera mit thyreoglobulinvorbehandelter Tiere auch auf Normaltiere übertragbar ist, d. h. bei Ratten durch eine mit Antithyreoglobulin-Immunserum durchgeführte passive Immunisierung die O₂-Verbrauch-steigernde Wirkung des eingespritzten Thyroxins aufgehoben wurde.Mit 7 Textabbildungen.     

Ueber die Empfindlichkeit des normalen Auges für Wellenlängen-Unterschiede des Lichtes

Ohne Zusammenfassung     

SCAR DISABILITIES OF WOUNDED HANDS

1. The importance of early relief of scar disabilities of the hand is emphasized–that is, before joint changes are established. 2. The part of early wound healing, early function and correct use of physiotherapy in preventing and minimizing scar disabilities of the hand is stated. 3. The “hand grenade” type of injury is described and used as a basis to describe the principles of an effective scar excision and replacement by a full-thickness skin graft. 4. A “through” type of hand wound is described in so far as scar effects are concerned. The principles of effective treatment by (a) scar excision and rearrangement for small scars and (b) scar excision and direct flap replacement for large scars are set out. 5. Other types of scar disability and their treatment are indicated– namely, web scars, adherent scars of fingers and burn scars. 6. A plea is made for the full application of plastic surgery to obtain better results from all hand wounds.