Application of boron-entrapped stealth liposomes to inhibition of growth of tumour cells in the in vivo boron neutron-capture therapy model.

Tumour cell destruction in boron neutron-capture therapy (BNCT) is due to the nuclear reaction between (10)B and thermal neutrons. It is necessary for effective BNCT therapy to accumulate (10)B atoms in the tumour cells. The delivery system consisted of polyethylene-glycol (PEG) binding liposomes (DPPC/cholesterol/DSPC-PEG2000) with an entrapped (10)B-compound and we evaluated the cytotoxic effects of intravenously injected (10)B-PEG-liposomes on human pancreatic carcinoma xenografts in nude mice with thermal neutron irradiation. After thermal neutron irradiation of mice injected with (10)B-PEG-liposomes, growth of AsPC-1 tumours was suppressed relative to controls. Injection of (10)B-PEG-liposomes caused the greatest tumour suppression with thermal neutron irradiation in vivo. These results suggest that intravenous injection of (10)B-PEG-liposomes can increase the retention of (10)B atoms by tumour cells, causing suppression of tumour growth in vivo, after thermal neutron irradiation.

Analysis of Tsuge's procedure for the treatment of radial nerve paralysis.

Radial deviation and limited flexion of the wrist joint and a lack of abduction of the thumb have been noticed after the Riordan's procedure. Therefore, Tsuge et al. modified the Riordan's procedure, and their procedure includes transfer of the pronator teres to the extensor carpi radialis brevis, the flexor carpi radialis (FCR) to the extensor digitorum communis (EDC), and the palmaris longus to the extensor pollicis longus, along with tenodesis of the abductor pollicis longus. We reviewed the charts of 21 patients with isolated radial nerve paralysis who were treated with the Tsuge's procedure. Mean follow-up period was 11.3 years. Postoperatively, patients showed good extension of the metacarpophalangeal joint measured at the middle finger, useful flexion of the wrist joint, and decreased radial deviation of the wrist. The FCR transfer to the EDC is an excellent procedure for extension of the fingers. However, reconstruction of active abduction of the thumb remains controversial.

Treatment of subungual glomus tumour.

We reviewed 30 patients with subungual glomus tumours of the hand operated on between 1964 and 1997. Seven patients were male and 23 were female. Their age ranged from 16 to 78 years. A transungual approach was selected in 27 patients, and a periungual approach in three. Pre-operative pain subsided in all of the patients, but recurrence of the pain was observed in nine. Nail deformities were observed in nine patients before surgery. After surgery, it disappeared in three patients, persisted in six, and new deformities developed in five. To avoid recurrence of pain, it is important that the accurate pre-operative localisation of the tumour and a complete extirpation should be performed. To avoid nail deformity, it is better to apply a periungual approach for tumours developing in the peripheral region, and a transungual approach followed by meticulous repair of the nail bed for tumours developing in the central region.

Liposomes bearing polyethyleneglycol-coupled transferrin with intracellular targeting property to the solid tumors in vivo.

PURPOSE: The purpose of this study was to determine the usefulness of transferrin (TF)-pendant-type polyethyleneglycol (PEG)-liposomes (TF-PEG-liposomes), in which TF was covalently linked to the distal terminal of PEG chains on the external surface of PEG-liposomes as a carrier for in vivo cytoplasmic targeting to tumor cells. METHODS: Small unilamellar TF-PEG-liposomes (100-140 nm in diameter) were prepared from DSPC, CH, DSPE-PEG, and DSPE-PEG-COOH (2:1:0.11:0.021, molar ratio), and were conjugated to TF via the carboxyl residue of DSPE-PEG-COOH. The intracellular targeting ability of TF-PEG-liposomes to tumor cells was examined in vitro and in Colon 26 tumor-bearing mice. RESULTS: TF-PEG-liposomes, bearing approximately 25 TF molecules per liposome, readily bound to mouse Colon 26 cells in vitro and were internalized by receptor-mediated endocytosis. TF-PEG-liposomes showed a prolonged residence time in the circulation and low RES uptake in Colon 26 tumor-bearing mice, resulting in enhanced extravasation of the liposomes into the solid tumor tissue. Electron microscopic studies in Colon 26 tumor-bearing mice revealed that the extravasated TF-PEG-liposomes were internalized into tumor cells by receptor-mediated endocytosis. CONCLUSION: TF-PEG-liposomes had the capabilities of specific receptor binding and receptor-mediated endocytosis to target cells after extravasation into solid tumors in vivo. Such liposomes should be useful for in vivo cytoplasmic targeting of chemotherapeutic agents or plasmid DNAs to target cells.

Three-dimensional morphological analysis of antigen-antibody reaction in hepatic sinusoids preserved in hypothermic UW solution.

ICAM-1 antigen-antibody reaction was visualized by three-dimensional immunoscanning electron microscopy of hepatic sinusoids in rat liver treated with hypothermic University of Wisconsin (UW) organ preservation solution. The results were compared with similar antigen-antibody reactions carried out with immunoliposomes injected in vivo. Morphologically, the hepatic sinusoids were preserved well during the hypothermic procedure. Endothelial cells had a large number of fenestrations, which partly aggregated and formed sieve plates. ICAM-1 expression was induced by injection of LPS and detected by monoclonal antibody in the UW solution followed by gold-labeled secondary antibody. ICAM-1 was restricted mostly to the unique areas of sieve plates with immature, small fenestrations. A similar distribution of ICAM-1 was present when detected by in vivo injection of immunoliposomes containing the monoclonal ICAM-1 antibody. The results showed that antigen-antibody reactions can take place in livers preserved in hypothermic UW solution. Further, the reaction is similar to that which could occur in vivo during transplantation. This suggests that it may be possible to block potentially harmful antigen-antibody reactions by addition of appropriate antibodies to hypothermic UW solution prior to transplantation.

Free vascularized toe joint transfer to the hand. A technique for simultaneous reconstruction of the soft tissue.

Twelve patients underwent reconstruction of injured finger joints using our technique of a vascularized transfer of the second toe proximal interphalangeal joint. The age of the patients at operation ranged from 7 to 47 years and the postoperative follow-up was 9 to 48 months. All the joint transfers survived and united with resolution of the preoperative joint pain, deformity and instability. The average range of motion of the reconstructed joints was 59 degrees in the proximal interphalangeal and 54 degrees in the metacarpophalangeal joints. No patient complained of pain or functional deficits in the donor foot.

Carpal tunnel syndrome in radial dysplasia.

We treated three patients for carpal tunnel syndrome which developed more than 10 years after reconstructive surgery for radial dysplasia. All responded to decompressive surgery. The radial carpal bones were hypoplastic in all cases, and in two we measured the carpal tunnel with computed tomography (CT). This showed that the anteroposterior diameter and cross-sectional area of the carpal tunnel were small because of the hypoplasia of the carpal bones. We believe carpal tunnel syndrome occurs with radial dysplasia because of the narrow anteroposterior diameter and small cross-sectional area of the carpal tunnel.

Clinical assessment of long-term safety and efficacy of a widely implanted polyacrylic intraocular lens material.

PURPOSE: To evaluate the long-term safety and efficacy, in a large series of patients, of polyacrylic intraocular lens implants 1 and 3 years after surgery, compared with polymethylmethacrylate intraocular lens implants. METHODS: This was a randomized, prospective study of 1,514 eyes of 1,202 patients that were examined for a 1-year follow-up study and 1,264 eyes of 990 patients that were examined for a 3-year follow-up study. All the patients were prospectively randomized to receive a polyacrylic or polymethylmethacrylate intraocular lens implant. A standardized surgical protocol was performed using a phacoemulsification technique and capsulorhexis. Any surgical complications were excluded, and all patients had standard postoperative medication and follow-up. Postoperative measurements included spectacle-corrected visual acuity, occurrence of postoperative sight-threatening or lens-related complications, and adverse reactions. Results were compared between the polyacrylic intraocular lens and polymethylmethacrylate intraocular lens groups. Results were also compared with standards for polymethylmethacrylate intraocular lens that were established by the US Food and Drug Administration and a previous study for silicone lens. RESULTS: The overall complete follow-up rates were 79.9% for 1-year follow-up and 69.5% for 3-year follow-up. At 1 year, the mean logarithm of the minimum angle of resolution (logMAR) of visual acuity was 0.037 +/- 0.150 and 0.042 +/- 0.154 in best case patients of the polyacrylic intraocular lens group and polymethylmethacrylate intraocular lens group, respectively. At 3 years, the mean logMAR visual acuity was 0.038 +/- 0.155 and 0.054 +/- 0.181 in best case patients in the polyacrylic intraocular lens group and polymethylmethacrylate intraocular lens group. There was no significant difference between groups at 1 and 3 years. At 1 year, 96.8% of best case patients in the polyacrylic intraocular lens group and 95.8% of those in the polymethylmethacrylate intraocular lens group achieved corrected visual acuity of 0.5 or better. At 3 years, 96.4% of best case patients in the polyacrylic intraocular lens group and 94.9% of those in the polymethylmethacrylate group achieved a corrected visual acuity of 0.5 or better; no significant difference was found at 1 and 3 years. The rate of sight-threatening complications was 1. 2% for the polyacrylic intraocular lens group of all patients and 1. 5% for the polymethylmethacrylate intraocular lens group at 1 year, and 1.6% for the polyacrylic intraocular lens group and 1.4% for the polymethylmethacrylate intraocular lens group at 3 years. No significant difference was found between the groups. The cumulative rate of Nd:YAG capsulotomy for the polyacrylic intraocular lens group (7.1%) was significantly lower than that for the polymethylmethacrylate intraocular lens group (38.1%) through 3 years (P <.0001). CONCLUSIONS: Polyacrylic intraocular lenses demonstrated safe and effective performance through long-term follow-up at a level equal to or better than polymethylmethacrylate intraocular lenses. Patients undergoing polyacrylic intraocular lens implantation achieved excellent postoperative visual acuity and experienced a low rate of postoperative complications, adverse reactions, and Nd:YAG capsulotomy. These long-term clinical results are an important outcome database for the ongoing use of this foldable optic material.

Trapeziometacarpal joint arthrodesis for the treatment of arthrosis.

We undertook a retrospective follow-up study of arthrodesis of 21 trapeziometacarpal joints in 19 patients. Internal fixation was by two or three Kirschner wires and a bone graft. No joint failed to unite. Painless joints and stable grasping were achieved. Subjective estimations of improvement were excellent for 16 joints. However, some patients complained of clumsiness after the procedure. Instability was seen in six metacarpophalangeal (MP) joints of the thumb. The most common indication for trapeziometacarpal joint arthrodesis was painful arthritis in vigorous, young male labourers. However, preoperative evaluation of the function of the MP joint is necessary to determine suitability for surgery.

Surgical treatment of the cleft foot.

Between 1970 and 1997, we treated a total of 32 cleft feet in 21 patients (11 male and 10 female). We classified cases of cleft foot on the basis of the number of central ray deficiencies. Fourteen patients with 22 cleft feet were followed up for more than 1 year postoperatively (9 feet had no or one central ray deficiency, and 13 feet had two or three central ray deficiencies). The mean follow-up period was 8.8 years. The objective of this study was to evaluate the results of operative treatment of cleft foot. We evaluated the results of three methods: simple closure of the cleft, application of a double-pedicled flap, and insertion of a silicone block. Cosmetic complications, including widening of the foot, hypertrophic scarring, pigmentation of the grafted skin, and overlapping of the toes, were observed in patients with two or three central ray deficiencies. Few functional complications were observed: None of the patients experienced gait disturbances, although one patient complained of pain following walking. Roentgenography showed that the distance between the first and fifth metatarsals was 86 percent of that of the contralateral foot. When treating patients with no or one central ray deficiency, satisfactory results can be expected with simple closure of the cleft. However, in patients with two or three central ray deficiencies, it is difficult to obtain satisfactory results with simple closure of the cleft or application of a double-pedicled flap. Therefore, silicone block insertion to correct the defect is recommended when there is more than one central ray deficiency.

Double-toe transplantation following temporary insertion of a block of silicone for reconstruction of a traumatic metacarpal defect.

The treatment of the mutilated hand with more than one digit missing and a metacarpal defect is challenging. We used double-toe transfer after temporary insertion of a block of silicone to fill the bony defect.

Targeting chemotherapy to solid tumors with long-circulating thermosensitive liposomes and local hyperthermia.

The effectiveness of the combination of long-circulating, thermosensitive liposomes and hyperthermia is described. Small-sized, thermosensitive liposomes that encapsulate doxorubicin (DXR-PEG-TSL (SUV)) have a prolonged circulation time and are extravasated to targeted solid tumors in vivo, where they preferentially release the agent in an anatomical site subjected to local hyperthermia. Liposomes were prepared by the incorporation of amphipathic polyethyleneglycol (PEG) to prolong their circulation time. DXR-PEG-TSL (SUV) was retained longest and was accumulated most efficiently in solid tumors in Balb/c mice. The combination of DXR-PEG-TSL (SUV) and hyperthermia at the tumor sites 3 h after injection, gave high concentrations of doxorubicin in tumor tissue and resulted in more effective tumor retardation and increased survival time. A large amount of DXR-PEG-TSL (SUV) was extravasated into the tumors during circulation for 3 h after injection, suggesting that the encapsulated drug was released into the interstitial spaces of the lesions by local hyperthermia. This system is expected to be clinically valuable for the delivery of a wide range of chemotherapeutic agents in the treatment of solid tumors.

Long-term results of fractionated strontium-90 radiation therapy for pterygia.

PURPOSE: The long-term safety and effectiveness of fractionated strontium-90 radiation therapy (RT) for pterygium were reviewed retrospectively. METHODS AND MATERIALS: Between 1984 and 1996, 399 patients with 490 pterygia were treated with a strontium-90 eye applicator following surgical removal of the pterygium. The median follow-up period was 61 months (range 2-178). Of the 490 pterygia, 452 were fresh, 17 were recurrences after surgical removal alone, and 21 were recurrences after surgical removal plus postoperative RT. Fractionated RT of 31-42 Gy/4-5 fractions/22-29 days was given for 95.1% of the pterygia. RESULTS: In total, 58 (11.8%) local recurrences of pterygia were noted. The median time of local recurrences was 10 months, ranging from 2 to 93 months, and 16 recurrences (28%) were noted later than 24 months after treatment. The interval between surgery and the start of RT (1-3 days vs. >3 days) and recurrent pterygia were significant variables for local control in the multivariate analysis, while total RT dose (7-29 Gy vs. 31-50 Gy) was a marginally significant variable. Late toxicities that may be associated with strontium-90 RT were scleromalacia (scleral thinning) in 4 eyes, adhesion of eyelids in 3 eyes, and scleral ulcer in 2 eyes. CONCLUSION: Fractionated strontium-90 RT of approximately 40 Gy/4-5 fractions was safe and effective for preventing recurrence of pterygia, when RT was started within 3 days of surgery.

Rejection and regeneration in peripheral nerve homografts in rats after withdrawal of cyclosporin: morphological and immunohistochemical assessment.

Peripheral nerve homografts 35 mm long were inserted in rats to study rejection and regeneration of nerves after suspension of an immunosuppressant (cyclosporin), and the correlation between the Schwann cells of the host and the donor during the course of regeneration. Sciatic nerve homografts from 36 ACI-RT1a rats were transplanted into Lewis-RT1(1) rats. Isografts were taken from 24 Lewis rats. Cyclosporin 5 mg/kg/day was given subcutaneously for 12 weeks. In the homograft group the myelinated axons that regenerated while the immunosuppressant was being given were covered mainly with Schwann cells from the donor, and after the immunosuppressant was withdrawn both Schwann cells of the donor and axons were rejected. However, while the cyclosporin was being given the Schwann cells of the host migrated into the nerve graft together with a few myelinated axons that escaped rejection, and unmyelinated axons that regenerated after rejection were myelinated by the Schwann cells of host.

Size-dependent extravasation and interstitial localization of polyethyleneglycol liposomes in solid tumor-bearing mice.

We have examined the size dependence of extravasation and interstitial localization of polyethyleneglycol-coated liposomes (PEG-liposomes) in the solid tumor tissue by means of electron microscopic observation. Liposomes composed of distearoyl phosphatidylcholine, cholesterol and distearoylphosphatidylethanolamine derivative of polyethyleneglycol (PEG) were prepared in various size ranges. PEG-liposomes with an average diameter of 100-200 nm showed the most prolonged circulation time and the greatest tumor accumulation in all the solid tumors employed in this experiment. Although large PEG-liposomes with a diameter of 400 nm showed a short circulation time in normal mice, the results in splenectomized mice indicated that they do have an intrinsic prolonged circulation character in vivo. However, large PEG-liposomes could not extravasate into solid tumor tissue. These results indicate that the size of liposomes is critical for extravasation. The electron microscopic observations revealed the almost exclusive engulfment of extravasated liposomes by tumor-associated macrophages; very few were taken up by tumor cells.

Possibility of active targeting to tumor tissues with liposomes.

In terms of active targeting by immunoliposomes, two anatomical compartments are considerable for targeting sites. One is located a readily accessible site in intravascular, and another is a much less accessible target site located in the extravascular. However, it was made clear that the active targeting with immunoliposomes is determined by two kinetically competing processes, such as binding to the target site and uptake by the RES. To overcome these contradictions, we have designed a new type of long-circulating immunoliposome, which was PEG-immunoliposome attached antibodies at the distal end of PEG chain, so called the pendant type immunoliposome. The pendant type immunoliposome showed much higher targetability than the ordinary immunoliposomes to both targeting sites of lung endothelial cells and solid tumor tissue. This is due to the free PEG chains (not linked to the antibody) effectively avoiding the RES uptake of liposomes, resulting in elevated the blood concentration and enhanced the target binding of immunoliposomes. The presence of free PEG does not interfere with the binding of the terminally linked antibody to the antigen. For targeting to the vascular endothelial surface in the lung, 34A antibody, which is highly specific to mouse pulmonary endothelial cells, was conjugated to make the pendant type immunoliposomes (34A-PEG-ILP). 34A-PFG-ILP showed significantly higher targeting degree than the ordinary type of immunoliposomes. For targeting to the solid tumor tissue, Fab' fragment of 21B2 antibody which is anti-human CFA and transferrin (TF) were used. Both pendant type immunoliposomes (Fab'-PFG-ILP and TF-PEG-ILP) showed the low RES uptake and the long circulation time, and resulted in enhanced accumulation of the liposomes in the solid tumor. TF-PEG-ILP was internalized into tumor cells with receptor mediated endocytosis, after extravasation into tumor tissue. The pendant type immunoliposome can escape from the gaps between adjacent endothelial cells and openings at the vessel termini during tumor angiogenesis by passive convective transport much rather than ligand directed targeting. Active targeting to tumor tissue with the pendant type immunoliposome is particularly important for many highly toxic anticancer drugs for cancer chemotherapy. An ultimate goal of pendant type immunoliposome is the incorporation of a fusogenic molecule that would induce fusion of liposome following their binding to the target cells or their internalization by endocytosis. Such liposomal formulations should be useful for endocytotic internalization of plasmid DNA and other bioactive materials.

Genotype-phenotype correlation of patients with multiple endocrine neoplasia type 2 in Japan.

BACKGROUND: Multiple endocrine neoplasia type 2 (MEN 2) is a hereditary syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytoma and hyperparathyroidism. MEN 2 is caused predominantly by germ-line mutations of the RET proto-oncogene. This study aimed to clarify the genotype-phenotype correlation in MEN 2 patients in Japan in order to modify the clinical management according to the genotype. METHODS: Constitutive DNA of 64 MEN 2 patients (48 kindreds) were searched for mutations at exons 10, 11, 13, 14 and 16 of the RET proto-oncogene using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), direct sequencing and restriction enzyme digestion. The clinical characteristics of the patients were obtained from a previous nationwide questionnaire survey. RESULTS: Overall, 62 (96.9%) out of 64 patients had a germ-line point mutation at the hot spots. MTC and pheochromocytoma occurred equally in every genotype except C630S. Specific genotype had a correlation between tumor size and age at the operation for MTC or extent of MTC, i.e. C618S developed late onset type of MTC as compared with that of C634R, C634Y and M918T. Small MTC in C634R may be less aggressive than those in C634Y and M918T. CONCLUSIONS: DNA testing has good clinical implications for the management of patients with MEN 2 and the timing and operative procedures of thyroidectomy can be modified according to the genotype.

Long-term results of surgical treatment for macrodactyly of the hand.

A retrospective review was performed for 23 patients who were surgically treated for macrodactyly of the hand between 1964 and 1995. Treatment regimens varied among the patients, and more than two operative procedures were performed in 65 percent of the patients. At final follow-up, the average length of the affected digits was 102 percent of that of the normal contralateral side. The average circumference of the digits was 121 and 124 percent at the proximal interphalangeal and distal interphalangeal joints, respectively. The average range of motion was 65, 57, and 37 degrees at the metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints, respectively. Although it is difficult to compare treatment regimens, epiphysiodesis/epiphysectomy was quite effective in the prevention of longitudinal overgrowth of the digits, but resection of the hypertrophic nerves was unsuccessful in preventing finger overgrowth.

MR imaging of meniscal tears with discoid lateral meniscus.

OBJECTIVE: To study MR findings of meniscal tears with discoid lateral menisci (DLMs) and to evaluate the incidence and accuracy of MRI compared to arthroscopical surgery. MATERIAL AND METHODS: MR appearances of surgically proved torn discoid lateral menisci (DLM) were studied in 57 knees (40 patients). They were all performed with a 1.5T MR before surgery. MR sequences included T1- and T2* weighted images on both coronal and sagittal planes and 3D-axial images with a slice thickness of 0.7 mm. RESULT: Of 57 DLMs, there were 32 complete DLMs and 25 incomplete DLMs. Twenty-five of 32 complete DLMs had tears; including seven with intrasubstance tear, five with radial tear, five with other kinds of tears and eight with severe tears involving whole meniscus. On the other hand, 13 of 25 incomplete DLMs had tears; including two with intrasubstance tear, six with radial tear, four with other kinds of tears and one with severe tears. All DLMs were correctly diagnosed on MR images. Twenty-seven of 38 tears with DLM were correctly identified on conventional 2D MR images. This yielded 71.1% sensitivity, 100% specificity and 80.7% overall accuracy. When adding axial 3D MR images to 2D MR images, 36 of 38 tears were correctly diagnosed. A combination of both techniques yielded a sensitivity of 94.7% and a specificity of 100%. Ten of 11 radial tears with DLM were correctly identified on 3D axial images, where only three of them could be diagnosed on conventional 2D images. Eight of nine intrasubstance tears were correctly identified on 3D axial images, where six of them could be diagnosed on conventional 2D images. CONCLUSION: DLMs had a much higher incidence of meniscal tears than normally shaped lateral menisci and MR is the only modality of choice to evaluate them before surgery. Especially 3D axial MR images were quite useful in the detection of intrasubstance and radial tears often associated with DLMs.