Wide spectral range confocal microscope based on endlessly single-mode fiber

We report an endlessly single mode, fiber-optic confocal microscope, based on a large mode area photonic crystal fiber. The microscope confines a very broad spectral range of excitation and emission wavelengths to a single spatial mode in the fiber. Single-mode operation over an optical octave is feasible. At a magnification of 10 and λ = 900 nm, its resolution was measured to be 1.0 μm (lateral) and 2.5 μm (axial). The microscope's use is demonstrated by imaging single photons emitted by individual InAs quantum dots in a pillar microcavity.

The preparation of Pt nanoparticles by methanol and citrate

Platinum nanoparticles of 2-3 nm average size and ca. +/-2 nm distribution can be successfully prepared by methanol reduction while using sodium citrate as the stabilizer. Sol formation was investigated by UV-visible spectroscopy and EXAFS (extended X-ray absorption fine structure spectroscopy). The formation of Pt nanoparticles was confirmed by the presence of Pt-Pt bonding in the solution after a certain induction period in methanol-reduced sol with or without citrate. The possible two-step reduction of Pt(IV) was revealed by correlating EXAFS, UV-visible spectra and pH data. The presence of citrate resulted in a smaller Pt-Pt coordination number and a slower sol formation process. All these results prove that citrate acted as the stabilizer in this synthesis.

Platinum states in citrate sols by EXAFS

Platinum sols have been prepared by citrate reduction in the temperature range of 343-363 K. The Pt state in the solution was examined by EXAFS (extended X-ray absorption fine-structure spectroscopy). It did not show any PtPt bonding, a characteristic for reduced Pt sols. EXAFS model fitting further proved the presence of PtO with 4 oxygen neighbors, which suggests a tetraplanar coordination configuration. The possibility of neighboring Pt sharing oxygen ligand or the formation of PtO(x) is rejected by EXAFS model fitting. Citrate was found to be the most likely ligand to orient its oxygen end toward a charged Pt center. Thus we have revealed that the citrate treatment at this temperature range was clearly insufficient to reduce H2PtCl(6(aq)). Neither an extended period of reaction time nor an excess citrate reduced the Pt precursor. It is therefore highly recommended that the citrate sols should be carefully prepared and used.

Augmentation of tendon-bone healing by the use of calcium-phosphate cement

The healing of a hamstring graft to bone is the weak link in the reconstruction of a cruciate ligament using this donor material. We therefore investigated the augmentation of healing at the tendon-bone interface using calcium-phosphate cement (CPC).

We performed semitendinosus autograft reconstructions of the anterior cruciate ligament on both knees of 22 New Zealand white rabbits. The interface between the grafted tendon and the bone tunnel for one knee was filled with CPC. Six rabbits were killed at the end of the first and second post-operative weeks in order to evaluate the biomechanical changes. Two rabbits were then killed sequentially at the end of weeks 1, 3, 6, 12 and 24 after operation and tissue removed for serial histological observation.

Histological examination showed that the use of CPC produced early, diffuse and massive bone ingrowth. By contrast, in the non-CPC group of rabbits only a thin layer of new bone was seen. Mechanical pull-out testing at one week showed that the mean maximal tensile strength was 6.505 ± 1.333 N for the CPC group and 2.048 ± 0.950 N for the non-CPC group. At two weeks the values were 11.491 ± 2.865 N and 5.452 ± 3.955 N, respectively.

Our findings indicate that CPC is a potentially promising material in clinical practice as regards its ability to reinforce the fixation of the tendon attachment to bone and to augment the overall effectiveness of tendon healing to bone.

An alternative dressing for skin graft immobilization: negative pressure dressing

The key difficulty of skin grafting is keeping the graft immobilized on uneven surfaces involved with motion, such as the nuchal area, axilla, web spaces, and the perineal area. This study reports the development of a new idea of negative pressure dressing (NPD) to maintain good immobilization of the skin graft and, at the same time, not cause any significant distress in the patient's daily life. Furthermore, the components of this dressing are available in ordinary hospitals. In this report, there are eight cases of skin grafts which were applied by this method, and the average success rate was approximately 97%. Therefore, use of negative pressure dressings to safeguard immobilization of the skin graft is an appropriate alternative method for grafts on uneven or mobile surfaces.

Measurement of the volume of the pedicled TRAM flap in immediate breast reconstruction

The transverse rectus abdominis musculocutaneous (TRAM) flap is now accepted as the standard for breast reconstruction, but achieving symmetrical breast reconstruction is still a challenge. A precise estimate of the volume of the flap is necessary to reconstruct a symmetrical and aesthetically pleasing breast. Many methods have been developed to overcome this problem, but they have not been suitable for the pedicled TRAM flap. By using a self-made device based on the Archimedes' principle, the authors can calculate accurately the volume of the pedicled TRAM flap and predict reliably the breast volume intraoperatively. The "procedure" is based on a self-made box into which the pedicled TRAM flap is placed. Warm saline is added to the box and the flap is then removed. Flap volume is calculated easily by determining the difference between the preestimated volume of the box and the volume of the residual water. From February to May 2000, this method was used on 28 patients to predict breast volume for breast reconstruction. This study revealed that the difference of the maximal chest circumferences (the index of the breast volume) demonstrates a positive correlation with the difference of the volumes and weights between the mastectomy specimen and the net TRAM flap. However, a more closely positive correlation exists between the differences of maximal chest circumference volume (r = 0.677) than maximal chest circumference weight (r = 0.618). These data reveal that the reconstructed breast's volume has a closer relationship with the volume of the net pedicled TRAM flap, rather than with its weight.

Phosphorylation of the 24p3 protein secreted from mouse uterus in vitro and in vivo

The 24p3 protein is a 25 KDa glycoprotein, having been purified from mouse uterine fluid. Thr54, Ser88, and Thr128/Ser129 on the protein molecule were predicted to be the phosphorylation site of casein kinase II, protein kinase C, and cAMP-dependent protein kinase, respectively. Incorporation of phosphate to this protein from [gamma-32P]-ATP was tested in the solution suitable for the three kinases. Neither casein kinase II nor cAMP-dependent protein kinase reacted to the 24p3 protein; however, protein kinase C demonstrated phosphorylation to this protein. This phosphorylation may be competing with a polypeptide segment: Arg79-Tyr-Trp-Ilu-Arg-Thr-Phe-Val-Pro-Ser88-Ser-Arg-Ala-Gly-Gln-Phe-Thr-Leu-Gly97 in the 24p3 protein molecule. To support this theory, Ser88 is a phosphorylation site of protein kinase C on 24p3 protein. The enzyme kinetic parameter, based on the Michaelis-Menten equation, determined Km to be 2.96 microM in the phosphorylation of 24p3 protein by the kinase. Both of the phosphorylated and dephosphorylated form of 24p3 protein can enhance the cAMP-dependent protein kinase activity in vitro. In addition, this experiment will show for the first time that serine-phosphorylated 24p3 protein exists in mouse uterine tissue.

Nonendoscopic harvest of the gastrocnemius muscle flap through a small incision

Traditional gastrocnemius flap harvest requires a long skin incision, starting from the popliteal fossa to the mid leg. The authors designed three instruments to facilitate harvest of this flap through a small incision without the help of an endoscope in 10 patients. All 10 gastrocnemius muscle flaps survived with a 100% success rate.

Endometrioma in a cesarean section scar--a case report

Scar endometriosis remains quite rare and there is only one case report in the literature of plastic surgery. We present a case of endometrioma appearing on the cesarean section scar. The classic symptom was a painful scar that became swollen and more tender during menstruation. The cause of surgical scar endometriosis is believed to be iatrogenic transplantation of endometrium to the surgical wound. Surgical excision remains the treatment of choice. This entity must be kept in mind by plastic surgeons evaluating patients who present with soft-tissue masses of the abdominal wall in the setting of previous combined hysterectomy and abdominoplasty.

Congenital multiple plaque-like glomangiomyoma in trunk--a case report

Congenital glomus tumor is a rare variant of glomus tumor, and glomangiomyoma is the least frequent histological type of glomus tumor. We present a case of congenital multiple plaque-like glomangiomyoma in an 11-year-old child with multiple diffuse plaques on his right lateral trunk. Histopathologic study showed a picture of typical glomus cell undergoing transition to smooth muscle cell. After literature review, this might be the first case report of congenital multiple plaque-like glomus tumor in trunk with histological appearance of a glomangiomyoma.

Tarsal tunnel syndrome secondary to neurilemoma--a case report

Peripheral nerve entrapment syndromes in the foot include those symptom complexes that are primarily neurologic in origin and result from embarrassment to any of the peripheral nerve trunks or branches of the foot. Tarsal tunnel syndrome usually is precipitated by compression of the tibial nerve posterior and distal to the medial malleolus. A neurilemoma is relatively uncommon in the foot. It is usually a solitary tumor that is almost exclusively benign and can be removed without jeopardizing the integrity of the nerve. Diagnosis is based on a thorough history and clinical pictures. Certain diagnostic modalities, ultrasound and MRI, have been employed to aid in diagnosis. Surgical excision of the tumor remains the treatment of choice.

Aesthetic resection of the gastrocnemius muscle in postpoliomyelitis calf hypertrophy: an uncommon case report

Muscle hypertrophy is a rare finding in neurologic lesions. Infiltration, stretching, and exercise of the muscle are causative factors of enlargement and hypertrophy. We report a case of unilateral calf hypertrophy postpoliomyelitis. The resection of the total medial and partial lateral gastrocnemius muscle was performed to achieve left calf reduction and a symmetrical contour of both legs. The patient is satisfied with the results and has not complained of any instability in walking or running after 2 years of follow-up.

Endoscopic excision of benign tumors in the forehead and brow

Twenty-five cases of benign tumor of the forehead and brow were excised successfully with endoscope-assisted surgery. The access incision was selected strategically behind the front hairline. For tumors in the middle of the forehead, the tumor was approached by subgaleal dissection. For those in the brow or temporal area, the dissection plane was just superficial to the deep temporal fascia. Patient age ranged from 3 to 59 years. The mass varied in size from 1.0 x 0.5 to 2.0 x 2.0 cm. There were 18 lipomas, 6 dermoid cysts, and 1 pilomatricoma. There was no residual mass or recurrence 1 to 24 months postoperatively. There was no paresthesia or numbness in the scalp. Patients and their families were greatly satisfied with this operation and the absence of visible scarring.