Novel biomedical imaging approach for detection of sentinel nodes in an experimental model of gastric cancer.

BACKGROUND: The aim of this study was to validate a novel imaging system that uses ATX-S10Na(II) to detect sentinel nodes (SNs) in gastric cancer. The new technique was compared with the enhanced visualization method using indocyanine green (ICG). METHODS: Human gastric carcinoma cells were implanted orthotopically into 50 nude rats, which were divided into two groups. In the first group (n = 25), ATX-S10Na(II) was injected subserosally into the implanted site and visualized by a fluorescence spectrolaparoscope. In the second group (n = 25), ICG was similarly injected and observed through a near-infrared laparoscope. The presence of metastatic tumour cells was determined by reverse transcriptase-polymerase chain reaction specific for human beta-actin. RESULTS: ATX-S10Na(II) was clearly identified as a bright red colour, and was rapidly incorporated into the lymphatic system. Detection rates of SNs were 100 (95 per cent confidence interval (c.i.) 52 to 100) per cent (25 of 25) for ATX-S10Na(II) and 95 (95 per cent c.i. 40 to 100) per cent (21 of 22) for ICG. Sensitivity was 96 (95 per cent c.i. 45 to 100) and 81 (95 per cent c.i. 58 to 95) per cent respectively. CONCLUSION: These results support the validity of the ATX-S10Na(II)-guided approach in the detection of SNs in gastric cancer in vivo.

Temperature diagnostics for cold sodium atoms by transient four-wave mixing.

Transient four-wave mixing signals were observed in cold sodium atoms. This phenomenon is interpreted as Bragg diffraction of a probe pulse by a population grating of the ground-state hyperfine level induced by pump pulses. The decay time of this grating is directly related to the temperature of the cold atoms and can serve as a novel technique for temperature diagnostics.

Total dephasing-rephasing balancing in Stark-pulse-modulated photon echoes.

Using Stark-pulse-modulated photon echoes, we observe a novel type of rephasing phenomenon in a Eu(3+) - and Pr(3+) -codoped Y(2)SiO(5) crystal. By adjusting the Stark pulse during the rephasing and dephasing periods one can observe a full recovery of the photon echo, corresponding to perfect dephasing-rephasing balancing of the perturbations. We propose to use this effect as a spectroscopic technique to distinguish between reversible and irreversible Stark interactions.

Late patellar tendon ruptures after removal of the central third for anterior cruciate ligament reconstruction. A report of two cases.

Patellar tendon rupture after removal of the central third for ACL reconstruction is a rare complication. Only nine cases have been previously reported, and all of these occurred within the first 10 months after surgery. We report two cases of late patellar tendon ruptures occurring at more than 3 and 6 years, respectively, after surgery. A review of the literature has suggested but not conclusively supported that devascularization, an alteration in tendon healing and remodeling, or injury to the remaining tendon at the time of graft harvest may be possible causes of this rare complication. Biopsy tissue from any future patellar tendon ruptures after removal of its central third could contribute to a better understanding of this anomaly.

Holographic motion picture by Eu(3+):Y(2)SiO(5).

Real-time recording of a moving object was made with persistent spectral hole burning of a cryogenic Eu(3+):Y(2)SiO(5) crystal. In a basic holographic configuration the ultrastable laser frequency was continuously scanned within the (7)F(0)-(5)D(0) absorption line (typically 200 MHz in 20 s) while the object was in motion, thus permitting the storage and reconstruction of the moving image. The success of this motion picture is attributable to (1) the kilohertz-wide hole width, (2) the quasi-persistent hole lifetime, and (3) the high hole-burning quantum efficiency of this material.

Allograft salvage of failed total elbow arthroplasty. A report of two cases.

Infection after total elbow arthroplasty (TEA) is a devastating complication. Current management options include (1) salvage of the implant with debridement and parenteral antibiotics, (2) resection arthroplasty, and (3) arthrodesis. Most infected TEA patients ultimately require resection arthroplasty. Inadequate bone may preclude both revision TEA and successful resection arthroplasty. It is in these cases that the patient may benefit from allograft reconstruction. Two patients with painful flail elbows secondary to previous resection arthroplasties were treated successfully with cadaver allograft augmented with in situ autograft. Use of the allograft resulted in improvement from failure to excellent in this patient with posttraumatic arthrosis at five years after operation and from failure to good in a rheumatoid patient at two years after operation. Autograft-augmented allografts in the resected failed-TEA patient are a valuable and bone-preserving option. This may be especially useful in patients with significant bone loss or young patients with posttraumatic arthrosis, for whom arthrodesis may be the only other surgical option. The method should not preclude further revision TEA.

Total sacrectomy for a giant sacral schwannoma. A case report.

Giant sacral schwannomas (GSS) are extremely rare. Complete resection of benign but neurologically devastating tumors has been recommended. A 48-year-old man with GSS had a tumor so large that a total sacrectomy was necessary. A special method of lumbar iliac fixation was devised. Two years and nine months after surgery, the patient was free of pain and ambulating with bilateral orthoses.

Kilohertz-resolution pump-probe spectroscopy in Pr(3+):YAlO(3).

We observed saturated absorption spectra of hole widths as narrow as 10.5 kHz with an excellent signal-to-noise ratio in a cryogenic Pr(3+):YA1O(3) sample, using a frequency-stabilized dye laser in a noncollinear frequency-domain pump-probe measurement. More-detailed theoretical and experimental analyses revealed the existence of an ultranarrow peak of width 10 Hz at the center of the line shape that could be attributed to grating diffraction of the pump beam.

Intragluteal spindle cell hemangioendothelioma. An unusual presentation of a recently described vascular neoplasm.

A 40-year-old woman noted a large tumor mass in the left buttock that, on microscopic examination, proved to be a recently described, relatively uncommon spindle cell hemangioendothelioma. This particular neoplasm, which has some features of Kaposi's sarcoma, seems not to have been reported previously in a deep, intramuscular location.

The use of periosteally vascularized autografts to augment the fixation of large segmental allografts.

Large segmental bone grafts are a standard of reconstructing long bone defects. Nonunion or delayed union at the host-graft junction is a major complication of these procedures. In six patients, a nonunion was treated by locally available bone, vascularized by its periosteum as an onlay autograft to improve fixation and speed incorporation of the allograft into the host bone. At three months, all were pain free and using their allografts without limitation. By four months, all had roentgenographic evidence of allograft and autograft incorporation. During the follow-up period from two to four years, all have incorporated the allografts and are pain free.

Microscopically assisted posterior lumbar interbody fusion.

Microscopically assisted posterior lumbar interbody fusion was performed on 27 patients who had either spondylolisthesis or chronic lower back pain after previous lower back surgery. Overall improved satisfactory results occurred in 22 of 27 patients. Roentgenographic, stable, interbody fusion occurred in 22 of 27 patients. The poorest results and highest rate of pseudarthrosis occurred in patients with double-level fusions. Pseudarthrosis occurred in four of six patients with double-level fusions and unsatisfactory clinical results occurred in five of six patients with double-level fusions. Advantages of the microscopic technique are better examination of the surgical site, less blood loss, and less surgical dissection than other surgical salvage techniques. This procedure should be reserved for single-level pathology in the lumbosacral spine.

Spectrally programmed stimulated photon echo.

A stimulated photon echo has been observed from the artificially modulated inhomogeneous distribution of a medium. A cryogenic Eu (3+):YAlO(3) sample with a quasi-persistent hole lifetime is exposed to a frequency-scanned and intensity-modulated cw laser for multiple hole burning. A coherent burst equivalent to the stimulated photon echo is obtained by triggering this sample by a pulsed laser. We demonstrate further that any desired transient pulse shape can, in principle, be obtained by appropriate frequency-domain programming, which opens the way to a novel type of optical memory.

Ultralong optical dephasing time in Eu(3+):Y(2)SiO(5).

We report what is to our knowledge the first measurement of linear and nonlinear spectroscopic properties for the (7)F(0)-(5)D(0) transition of Eu(3+):Y(2)SiO(5). Two clearly resolved lines at 579.879 and 580.049 nm, stemming from different sites, show dissimilar photoluminescence and hole spectra. In addition, these two sites have different inhomogeneous and homogeneous linewidths, which suggests that the local-field effect is smaller for one site. Specifically, the less affected site exhibits the longest dephasing time (822 micros) of any solid, which corresponds to a homogeneous linewidth of 387 Hz, and this linewidth is found to persist for hours without apparent spectral diffusion.

Time- and frequency-domain hybrid optical memory: 1.6-kbit data storage in Eu(3+):Y(2)SiO(5).

We propose and demonstrate a novel type of frequency-selective optical memory that writes and reads the data in both the time domain and the frequency domain. Temporal 16-bit data were stored by accumulated-photon-echo bit-by-bit storage at 103 frequency addresses within the inhomogeneous line of the (7)F(0)-(5)D(0) transition of Eu(3+):Y(2)SiO(5), which yields a total memory capacity of 1.6 kbits in a single spot of 240-microm diameter. The keys to the success of this experiment are this material's long dephasing time and lack of spectral diffusion.