A Free Bypass Flap for Chronic Limb-threatening Ischemia.

Background: Recently, significant inframalleolar disease seems to increase in chronic limb-threatening ischemia (CLTI) patients, making identifying sufficient outflow vessels in the foot challenging. In these difficult situations, free tissue transfer is a valuable tool to provide a low-resistance vascular bed to the affected part. However, there remains concern that free tissue transfer may impede adequate perfusion of the higher resistance diseased vascular bed. Methods: To improve perfusion of the affected area directly, the authors have developed a concept of a free bypass flap, adding bypass surgery to free tissue transfer. After anastomosis with the recipient vessels in a conventional manner for free tissue transfer, bypass surgery to the foot is performed by anastomosis of the branch of the flap pedicle with the diseased artery to the foot. A retrospective chart review of nine CLTI patients was performed to analyze the outcomes of free bypass flap transfer between 2018 and 2023. Results: The flap success rate was 100% (n = 9). Postoperative angiography or echo confirmed the patency of all but one bypass vessel (n = 8). There were six fatalities, however, due to causes other than foot lesions, with an average observation period of 16 months. The limb salvage rate was 89% (n = 8). Conclusions: A free bypass flap enhances the overall blood circulation to the foot. Due to its high patency rate of bypass vessels, it is a valuable method for preserving the limbs of highly comorbid patients with CLTI.

Long-term survival of the Sister Mary Joseph nodule originating from breast cancer: A case report.

BACKGROUND: A Sister Mary Joseph nodule (SMJN) is an uncommon cutaneous metastasis found in the umbilicus, indicating an advanced malignancy. SMJNs typically originate from intra-abdominal sources, rarely from breast cancer. Diagnosis suggests a poor prognosis with a median survival of approximately 8 mo after detection. Managing patients with SMJNs is challenging, as most receive limited palliative care only. The optimal strategy for long-term survival of these patients remains unclear. CASE SUMMARY: A 58-year-old female, previously diagnosed with right breast cancer 17 years ago and underwent breast-conserving surgery, adjuvant radiotherapy, and endocrine therapy, presented with a 2-cm umbilical nodule. Thirteen years previously, metastases were detected in the right supraclavicular, infraclavicular, hilar, and mediastinal lymph nodes. An umbilical nodule emerged four years before the date of presentation, confirmed as a skin metastasis of primary breast cancer upon excisional biopsy. Despite initial removal, the nodule recurred and grew, leading to her referral to our hospital. The patient underwent extensive excision of the umbilical tumor and immediate abdominal wall reconstruction. Endocrine therapy was continued postoperatively. Five years later, no local recurrence was observed, and the patient continued to work full-time, achieving over 9 years of survival following SMJN diagnosis. CONCLUSION: This case study aimed to identify the optimal strategy for achieving extended survival outcomes in patients with SMJN through comprehensive treatment. We presented a case of the longest survival in a patient after undergoing a multidisciplinary treatment regimen. Our findings underscore the significance of adopting a multimodal treatment approach comprising timely and wide excision along with adjunctive therapy. This approach can control the disease, prolong survival, and improve the quality of life in patients with SMJN.

Switching nanoscale temperature fields with high-order plasmonic modes in transition metal nanorods.

Depending on the photoirradiation conditions, metal nanostructures exhibit various plasmonic modes, including dipolar, quadrupolar, and hexapolar modes. This work demonstrates numerically that these high-order plasmonic modes can be used to switch nanoscale temperature distributions during the plasmonic heating of a manganese (Mn) nanorod. The key feature of Mn is its low thermal conductivity. Generally, when noble metal nanostructures are used for plasmonic heating, the nanostructure surface will be almost isothermal regardless of the order of the excited plasmonic modes because of the high thermal conductivity of noble metals, e.g., the thermal conductivity of gold is 314 W m-1 K-1. However, unlike noble metals, Mn has a significantly lower thermal conductivity of 7.8 W m-1 K-1. Due to this lower thermal conductivity, the distinct spatial characteristics of the high-order plasmonic modes can be transcribed clearly into nanoscale temperature fields, which are achieved by generating polarization currents by high-order plasmons within the nanorod. These findings strongly suggest that high-order plasmonic modes hold significant potential for the advanced and precise manipulation of heat generation at the nanometer scale in thermoplasmonics.

Ultrafast sensitivity-controlled and specific detection of extracellular vesicles using optical force with antibody-modified microparticles in a microflow system.

Extracellular vesicles (EVs), including nanoscale exosomes and ectosomes, hold promise as biomarkers that provide information about the cell of origin through their cargo of nucleic acids and proteins, both on their surface and within. Here, we develop a detection method of EVs based on light-induced acceleration of specific binding between their surface and antibody-modified microparticles, using a controlled microflow with three-dimensional analysis by confocal microscopy. Our method successfully detected 103-104 nanoscale EVs in liquid samples as small as a 500 nanoliters within 5 minutes, with the ability to distinguish multiple membrane proteins. Remarkably, we achieved the specific detection of EVs secreted from living cancer cell lines with high linearity, without the need for a time-consuming ultracentrifugation process that can take several hours. Furthermore, the detection range can be controlled by adjusting the action range of optical force using a defocused laser, consistent with the theoretical calculations. These findings demonstrate an ultrafast, sensitive, and quantitative approach for measuring biological nanoparticles, enabling innovative analyses of cell-to-cell communication and early diagnosis of various diseases, including cancer.

Light-Induced Condensation of Biofunctional Molecules around Targeted Living Cells to Accelerate Cytosolic Delivery.

The light-induced force and convection can be enhanced by the collective effect of electrons (superradiance and red shift) in high-density metallic nanoparticles, leading to macroscopic assembly of target molecules. We here demonstrate application of the light-induced assembly for drug delivery system with enhancement of cell membrane accumulation and penetration of biofunctional molecules including cell-penetrating peptides (CPPs) with superradiance-mediated photothermal convection. For induction of photothermal assembly around targeted living cells in cell culture medium, infrared continuous-wave laser light was focused onto high-density gold-particle-bound glass bottom dishes exhibiting plasmonic superradiance or thin gold-film-coated glass bottom dishes. In this system, the biofunctional molecules can be concentrated around the targeted living cells and internalized into them only by 100 s laser irradiation. Using this simple approach, we successfully achieved enhanced cytosolic release of the CPPs and apoptosis induction using a pro-apoptotic domain with a very low peptide concentration (nM level) by light-induced condensation.

Attogram-level light-induced antigen-antibody binding confined in microflow.

The analysis of trace amounts of proteins based on immunoassays and other methods is essential for the early diagnosis of various diseases such as cancer, dementia, and microbial infections. Here, we propose a light-induced acceleration of antigen-antibody reaction of attogram-level proteins at the solid-liquid interface by tuning the laser irradiation area comparable to the microscale confinement geometry for enhancing the collisional probability of target molecules and probe particles with optical force and fluidic pressure. This principle was applied to achieve a 102-fold higher sensitivity and ultrafast specific detection in comparison with conventional protein detection methods (a few hours) by omitting any pretreatment procedures; 47-750 ag of target proteins were detected in 300 nL of sample after 3 minutes of laser irradiation. Our findings can promote the development of proteomics and innovative platforms for high-throughput bio-analyses under the control of a variety of biochemical reactions.

Nanoneedle formation via doughnut beam-induced Marangoni effects.

Recently, nanosecond pulsed optical vortices enables the production of a unique chiral and sharp needle-like nanostructure (nano-needle). However, the formation process of these structures has been unsolved although mass transport by angular momentum would contribute to the chirality. Here, we reveal that another key factor in the formation of a sharp nano-needle is the Marangoni effect during the melting condition at high temperature. Remarkably, the thickness and height of the nano-needle can be precisely controlled within 200 nm, corresponding to 1/25 of beam radius (5 µm) beyond the diffraction limit by ring-shaped inhomogeneous temperature rise. Our finding will facilitate the development of advanced nano-processing with a variety of structured light beams.

Wearable, wireless, multi-sensor device for monitoring tissue circulation after free-tissue transplantation: a multicentre clinical trial.

Wearable sensors have seen remarkable recent technological developments, and their role in healthcare is expected to expand. Specifically, monitoring tissue circulation in patients who have undergone reconstructive surgery is critical because blood flow deficiencies must be rescued within hours or the transplant will fail due to thrombosis/haematoma within the artery or vein. We design a wearable, wireless, continuous, multipoint sensor to monitor tissue circulation. The system measures pulse waves, skin colour, and tissue temperature to reproduce physician assessment. Data are analysed in real time for patient risk using an algorithm. This multicentre clinical trial involved 73 patients who underwent transplant surgery and had their tissue circulation monitored until postoperative day 7. Herein, we show that the overall agreement rate between physician and sensor findings is 99.2%. In addition, the patient questionnaire results indicate that the device is easy to wear. The sensor demonstrates non-invasive, real-time, continuous, multi-point, wireless, and reliable monitoring for postoperative care. This wearable system can improve the success rate of reconstructive surgeries.

Plasmonic nanoscale temperature shaping on a single titanium nitride nanostructure.

Arbitrary shaping of temperature fields at the nanometre scale is an important goal in nanotechnology; however, this is challenging because of the diffusive nature of heat transfer. In the present work, we numerically demonstrated that spatial shaping of nanoscale temperature fields can be achieved by plasmonic heating of a single titanium nitride (TiN) nanostructure. A key feature of TiN is its low thermal conductivity (kTiN = 29 [W m-1 K-1]) compared with ordinary plasmonic metals such as Au (kAu = 314 [W m-1 K-1]). When the localised surface plasmon resonance of a metal nanostructure is excited, the light intensity is converted to heat power density in the nanostructure via the Joule heating effect. For a gold nanoparticle, non-uniform spatial distributions of the heat power density will disappear because of the high thermal conductivity of Au; the nanoparticle surface will be entirely isothermal. In contrast, the spatial distributions of the heat power density can be clearly transcribed into temperature fields on a TiN nanostructure because the heat dissipation is suppressed. In fact, we revealed that highly localised temperature distributions can be selectively controlled around the TiN nanostructure at a spatial resolution of several tens of nanometres depending on the excitation wavelength. The present results indicate that arbitrary temperature shaping at the nanometre scale can be achieved by designing the heat power density in TiN nanostructures for plasmonic heating, leading to unconventional thermofluidics and thermal chemical biology.

Lymphatic-venous anastomosis for the treatment of refractory lymphatic ascites following radiation therapy: A case report.

Radical treatments for intra-abdominal malignancies disturb physiological lymphatic drainage and predispose the patients to lymphatic complications such as lymphatic ascites. Despite its infrequent occurrence, lymphatic ascites is a morbid complication, and a definitive treatment protocol for refractory cases has not been established. Surgical treatments are opted depending on the etiology, symptoms, and facility equipment. Lymphatic-venous anastomosis (LVA) bypasses the proximal lymphatic blockages and provides an alternative route for lymphatic fluid recirculation into the venous system, thereby improving the lymphatic congestion. Herein, we report the utility of LVA surgery in the treatment of refractory serous lymphatic ascites that developed after radiation therapy for cervical cancer in a 77-year-old woman. The patient had massive ascites and suffered from abdominal distention and anorexia for 1 year. The ascites was unresponsive to conservative treatment. Under local anesthesia, eight incisions were made in the lower extremities just above the lymphatic channels that were identified by indocyanine green lymphography, and a total of 14 LVAs were created. The postoperative course was uneventful, and the ascites improved significantly. The patient remained free from the recurrence of ascites during 3.5 years of postoperative follow-up. LVA surgery was effective for the improvement and long-term control of lymphatic ascites. This procedure may be a viable option for the management of lymphatic ascites.

Microsurgical Lymphovenous Anastomosis for Pelvic Lymphoceles after Gynecological Cancer Surgery.

BACKGROUND: Pelvic lymphoceles are the most common complications after pelvic lymphadenectomy. Microsurgical procedures have attracted attention as an alternative treatment for lymphoceles. Here, we report six cases of refractory lymphoceles that were successfully treated using lymphovenous anastomosis (LVA). METHODS: Six patients underwent surgery for gynecological cancers and developed pelvic lymphoceles, which did not respond to conventional treatment. We mainly performed LVA on the ipsilateral lower limbs, although some procedures were also performed on the contralateral limbs. The change in the lymphocele volume after LVA was examined using computed tomography and compared using the Wilcoxon test. RESULTS: Five of the six refractory lymphocele cases were successfully treated using LVA, and the remaining case exhibited an 87% reduction in lymphocele volume. The average numbers of anastomoses were 6.7 on the ipsilateral side and 2.8 on the contralateral side (the median numbers: 6 [range: 5-9] vs. 3 [range: 1-4], P = 0.034). The average lymphocele volume decreased significantly from 414.0 mL preoperatively to 8.0 mL postoperatively (the median lymphocele volume: 255.8 [range: 61.5-1,329.2] vs. 0 [range: 0-47.7], P = 0.0313). CONCLUSION: We found that microsurgical treatment was potentially effective for lymphoceles that did not respond to conventional treatment.

Formulation of resonant optical force based on the microscopic structure of chiral molecules.

Optical manipulation, exemplified by Ashkin's optical tweezers, is a promising technique in the fields of bioscience and chemistry, as it enables the non-destructive and non-contact selective transport or manipulation of small particles. To realize the separation of chiral molecules, several researchers have reported on the use of light and discussed feasibility of selection. Although the separation of micrometer-sized chiral molecules has been experimentally demonstrated, the separation of nanometer-sized chiral molecules, which are considerably smaller than the wavelength of light, remains challenging. Therefore, we formulated an optical force under electronic resonance to enhance the optical force and enable selective manipulation. In particular, we incorporated the microscopic structures of molecular dipoles into the nonlocal optical response theory. The analytical expression of optical force could clarify the mechanism of selection exertion of the resonant optical force on chiral molecules. Furthermore, we quantitatively evaluated the light intensity and light exposure time required to separate a single molecule in a solvent. The results can facilitate the design of future schemes for the selective optical manipulation of chiral molecules.

Damage-free light-induced assembly of intestinal bacteria with a bubble-mimetic substrate.

Rapid evaluation of functions in densely assembled bacteria is a crucial issue in the efficient study of symbiotic mechanisms. If the interaction between many living microbes can be controlled and accelerated via remote assembly, a cultivation process requiring a few days can be ommitted, thus leading to a reduction in the time needed to analyze the bacterial functions. Here, we show the rapid, damage-free, and extremely dense light-induced assembly of microbes over a submillimeter area with the "bubble-mimetic substrate (BMS)". In particular, we successfully assembled 104-105 cells of lactic acid bacteria (Lactobacillus casei), achieving a survival rate higher than 95% within a few minutes without cultivation process. This type of light-induced assembly on substrates like BMS, with the maintenance of the inherent functions of various biological samples, can pave the way for the development of innovative methods for rapid and highly efficient analysis of functions in a variety of microbes.

Sacral defect reconstruction using a sensate superior gluteal artery perforator flap based on the superior cluneal nerves: A report of two cases.

The superior gluteal artery perforator (SGAP) flap is a widely used flap for sacral reconstruction. However, it is non-sensate flap and sensory loss is one of the most important risk factors for pressure ulcer development and recurrence; therefore, a sensate SGAP flap would be ideal for the reconstruction. Because the upper buttock is innervated by the superior cluneal nerves (SCNs) which originate from Th11 to L4, a sensate SGAP flap based on SCNs is anatomically possible. Herein, we present a novel sensate SGAP flap based on SCNs for reconstruction of sacral defects. Two patients with a sacral defect underwent reconstruction using a sensate SGAP flap (53 and 56 years old, both men). Diagnoses were sacral spindle cell sarcoma and sacral pressure ulcer. The defect sizes were 16 × 13 and 12 × 11 cm. The flap was designed based on the locations of SCNs which are commonly located at 6-8 cm lateral from the midline at the iliac crest. Flap sizes were 16 × 9 and 15 × 13 cm, respectively. The flaps survived completely in both cases. Flap sensation was observed immediately after surgery except in flap margins. However, sensory recovery occurred in these areas as well several months postoperatively. None of the patients developed postoperative pressure ulcers during the follow-up period of 37 and 13 months. This method may preserve flap sensation and therefore can contribute to reducing the risk of postoperative pressure ulcers and could be a useful option for sacral reconstruction.

Silk fibroin vascular graft: a promising tissue-engineered scaffold material for abdominal venous system replacement.

No alternative tissue-engineered vascular grafts for the abdominal venous system are reported. The present study focused on the development of new tissue-engineered vascular graft using a silk-based scaffold material for abdominal venous system replacement. A rat vein, the inferior vena cava, was replaced by a silk fibroin (SF, a biocompatible natural insoluble protein present in silk thread), tissue-engineered vascular graft (10 mm long, 3 mm diameter, n = 19, SF group). The 1 and 4 -week patency rates and histologic reactions were compared with those of expanded polytetrafluoroethylene vascular grafts (n = 10, ePTFE group). The patency rate at 1 and 4 weeks after replacement in the SF group was 100.0% and 94.7%, and that in the ePTFE group was 100.0% and 80.0%, respectively. There was no significant difference between groups (p = 0.36). Unlike the ePTFE graft, CD31-positive endothelial cells covered the whole luminal surface of the SF vascular graft at 4 weeks, indicating better endothelialization. SF vascular grafts may be a promising tissue-engineered scaffold material for abdominal venous system replacement.

Near-field transmission and reflection spectroscopy for revealing absorption and scattering characteristics of single silver nanoplates.

Near-field optical microscopy visualizes spatial characteristics of elementary excitations induced in metal nanostructures. However, the microscopy is not able to reveal the absorption and scattering characteristics of the object simultaneously. In this study, we demonstrate a method for revealing the absorption and scattering characteristics of silver nanoplate by using near-field transmission and reflection spectroscopy. Near-field transmission and reflection images show characteristic spatial features attributable to the excited plasmon modes. The near-field refection image near the resonance shows a reversed contrast depending on the observed wavelength. Near-field reflection spectra show unique positive and negative resonant features. We reveal that the optical characteristics and the wavelength dependency of the optical contrast originate from the scattering and absorption properties of the plasmons, with the aid of the electromagnetic simulations.

Superficial Circumflex Iliac Perforator-Osteocutaneous Flap for Reconstruction of Extensive Composite Defects in the Forefoot.

Although the great toe plays important roles in walking, loading, and maintaining balance when compared with other toes, there are few reports on great toe reconstruction, including the reconstruction of distal phalanx. This report aims to describe the use of a superficial circumflex iliac artery perforator (SCIP)-osteocutaneous flap for reconstructing a complex tissue defect of the great toe. A 62-year-old man presented with a crush injury to the forefoot. Because the great toe was severely crushed, the defect distal to the proximal phalanx of the great toe was reconstructed using a SCIP-osteocutaneous flap. The immediate postoperative course was uneventful; however, surgical revision was necessary. Signs of osseous union could be observed on radiographic images taken 2 months after the initial surgery. Twenty-four months after surgery, the patient could freely walk without resorption of the transferred bone. We demonstrated that SCIP-osteocutaneous flaps may be promising free flaps in complex tissue defect reconstruction of the great toe.

Superthin Thoracodorsal Artery Perforator Flap for the Reconstruction of Palmar Burn Contracture.

Treating burn scar contractures is challenging. Although free flap transfer is an effective tool for hand reconstruction, free flaps are often bulky, causing functional disturbance and poor cosmetic appearance. Secondary debulking operations are required, resulting in a prolonged total treatment period and delayed return to daily life and work for the patient. Therefore, 1-stage reconstruction using a thin and pliable flap is ideal. In this report, we present the superthin TDAP flap as an option for the reconstruction of postburn palmar contracture. During TDAP flap elevation, the thoracodorsal artery perforator was identified and traced distally until its penetration into the dermis. Subsequently, the subdermal tissue was removed and a uniformly superthin TDAP flap was elevated. Postoperatively, early functional recovery was achieved with excellent palmar contour and texture. No revision surgery was required and no recurrence of contractures occurred during the 6-month follow-up. This procedure is useful in elevating a superthin TDAP flap and is a feasible option for the reconstruction of working surfaces, such as the palm.

Effective Secondary Reconstruction of Refractory Urethrocutaneous Fistula after Metoidioplasty Using Folded Superficial Circumflex Iliac Artery Perforator Flap.

One of the primary goals of penile reconstruction for female-to-male transsexuals is to enable voiding while standing. Metoidioplasty represents a viable option, but it is associated with a high rate of postoperative fistula formation and recurrence, which affects the aesthetic and functional outcomes. Subsequent surgical repair using scarred and inadequate local tissue may contribute to fistula recurrence. The folded superficial circumflex iliac artery perforator (SCIP) island flap offers sufficient well-vascularized tissue and skin envelope for the reconstruction of the urethra and outer skin after failed metoidioplasty. The SCIP flap can be elevated as a hairless thin flap, making it useful in urethral reconstruction even when it is folded. We describe a case of a 44-year-old female-to-male transsexual patient who developed a refractory urethrocutaneous fistula after metoidioplasty. Surgical repairs were attempted using local tissue 4 times without success. The patient presented to our hospital, and we performed urethral reconstruction using a folded, pedicled SCIP flap for both urethra and skin augmentation. The postoperative course was uneventful, with satisfactory functional results and low donor-site morbidity. No fistula recurrence was observed during the 2 years of follow-up. This novel procedure offers a viable alternative technique for refractory urethrocutaneous fistula repair.