Trends in Investigator-Initiated Clinical Studies at a University Hospital after Enforcement of the 2018 Clinical Trials Act in Japan.

In April 2018, the Clinical Trials Act pertaining to investigator-initiated clinical trials was passed in Japan. The purpose of this study was to investigate activity in investigator-initiated clinical studies before and after enforcement of the new Clinical Trials Act. This was done by analysing the records of the Ethics Committee of Tokushima University Hospital, which reviews studies based on the Japanese government's Ethical Guidelines for Medical and Health Research Involving Human Subjects prior to the Clinical Trials Act, and records of the Certified Review Board established at Tokushima University under the Clinical Trials Act in 2018. The number of new applications to these two review boards during fiscal years 2015-2017 (pre-Act) and fiscal years 2018 and 2019 (post-Act) were used as an indicator of activity in investigator-initiated clinical studies. The number of new applications to the Ethics Committee was 303, 261, 316, 303, and 249 in 2015, 2016, 2017, 2018, and 2019, respectively. The data show that the total number of new interventional studies decreased from 50.3 in average in 2015-2017 (pre-Act) to 42 in 2018 and 40 in 2019 (post-Act), respectively. These results suggest that fewer interventional studies were started following enforcement of the new Clinical Trials Act. To confirm this trend and identify contributing factors, further studies are required. In addition, possible way, such as broader contribution of clinical research coordinators, to promote clinical studies in the new Clinical Trials Act era should be examined.

Lateral Nasal Artery Perforator Flap for Nasal Reconstruction: Clinical Applications and Risk Factors Associated With Nasal Deformities.

BACKGROUND: Nasal reconstruction is challenging because of the difficulty in balancing superior aesthetic outcomes and less invasive surgery. The use of the lateral nasal artery (LNA) perforator flap has been reported for nasal reconstruction. However, few reports have described appropriate applications of nasal reconstruction and assessments of nasal deformity. This study aimed to quantify the aesthetic outcomes on using this flap and reveal the risk factors associated with nasal deformities. METHODS: Twenty patients underwent nasal reconstruction using the LNA flap with a cranial perforator adjacent to the nasal defect. Postoperative protuberant deformities were scored by 2 independent plastic surgeons using a 5-point Likert scale and classified as excellent, good, or poor. The risk factors of deformities were identified using univariate analyses. A nasal alar deviation index was developed to analyze correlations with flap harvesting. The sensory function was assessed by the Semmes-Weinstein test. RESULTS: Flaps survived in 19 patients (95%), and 1 flap showed distal necrosis. All arterial perforators used remained within 5 mm lateral to the boundary between the cheek and nasal ala. The flaps were most often used to cover 2 subunits, including the nasal sidewall defects. Protuberant deformities in 6 (30%), 8 (40%), and 6 (30%) patients were classified as excellent, good, and poor, respectively. Nasal defects involving more than 3 subunits caused severe protuberant deformity. Only 2 patients (5%) in the good and fair groups underwent additional debulking surgery. Nasal alar deviation was not significantly correlated with flap harvesting, when the nasal alar deviation index before and after surgery were compared. Sensory function was retained in all patients. CONCLUSIONS: Aesthetic outcomes and sensory function were good on using the LNA perforator flap as a propeller flap having a wide arc of rotation. This flap is suitable for nasal reconstruction involving less than 2 nasal subunits without any severe nasal alar deviation deformity. In addition, this flap allows for better outcomes because it requires less invasive 1-stage surgery.

Assessment of Adherence to Post-exposure Prophylaxis with Oseltamivir in Healthcare Workers: A Retrospective Questionnaire-Based Study.

Post-exposure prophylaxis (PEP) for healthcare workers is one of the effective strategies for preventing nosocomial outbreaks of influenza. However, PEP adherence in healthcare workers is rarely analysed, and no strategies have been established to improve adherence to PEP for healthcare workers. We aimed to retrospectively analyse adherence to PEP and the factors associated with non-adherence in healthcare workers. A survey of 221 healthcare workers who were eligible for PEP at Tokushima University Hospital in the 2016/2017 season was conducted. Once-daily oseltamivir (75 mg for 10 d) was used as the PEP regimen. Of the 221 healthcare workers, 175 received PEP and were surveyed for adherence using a questionnaire. Of the 130 healthcare workers who responded to the questionnaire, 121 (93.1%) had been vaccinated. In this survey, 82 healthcare workers (63.1%) did not fully complete PEP. Multiple logistic regression analysis revealed that physicians (odds ratio: 4.62, 95% confidence interval [CI]: 2.08-10.25) and non-vaccination (odds ratio: 9.60, 95% CI: 1.12-82.25) were the factors for non-adherence to PEP. Of the 47 healthcare workers who responded to the item regarding reasons for non-adherence, 36 (76.6%) reported forgetting to take oseltamivir or discontinuing it due to a misguided self-decision that continuation of PEP was unnecessary, and 5 (10.6%) reported discontinuing treatment due to adverse effects. In conclusion, healthcare workers, particularly physicians, had low PEP adherence owing to forgetting or stopping to take oseltamivir due to a misguided self-decision. To obtain the maximum preventive effect of PEP, medication education should be provided to endorse PEP compliance.

Long-term Management of a Patient with Apert Syndrome.

AIM AND OBJECTIVE: To present an Apert syndrome patient with midfacial growth deficiency treated with Le Fort III distraction osteogenesis and subsequent two-jaw surgery. BACKGROUND: Apert syndrome is expressed as a severe and irregular craniosynostosis, midfacial hypoplasia, and symmetric syndactyly in the fingers and toes. For craniosynostosis syndromes, treatment planning is complex due to the disharmony between facial profile and occlusion. CASE DESCRIPTION: A 4-year-and-5-month-old boy, diagnosed with Apert syndrome, showed a concave profile accompanied with midfacial hypoplasia, moderate exorbitism, a reversed occlusion of -10.0 mm, an anterior open bite of -5.0 mm, and skeletal class III jaw-base relationship. The patient, aged 15 years and 4 months, underwent a Le Fort III osteotomy, and subsequent osteodistraction was performed via a rigid external distraction (RED) device. His midfacial bone was advanced by approximately 7.0 mm. One year after the distraction, preoperative treatment with 0.018-in preadjusted edgewise appliances was initiated. Two-jaw surgery with a Le Fort I osteotomy and bilateral sagittal split ramus osteotomy was performed after 42 months of preoperative orthodontic treatment. At the age of 20 years and 9 months, his facial profile dramatically changed to a straight profile, and an acceptable occlusion with an adequate interincisal relationship was obtained. A functional occlusion with an excellent facial profile was maintained throughout the 2-year retention period, although the upper dental arch width was slightly decreased, resulting in the recurrence of the left posterior crossbite. CONCLUSION: Our report indicates the necessity of long-term follow-up in patients with craniosynostosis because of syndrome-specific growth and methodologically induced relapse. CLINICAL SIGNIFICANCE: The two-stage operation combining early distraction osteogenesis and postgrowth orthognathic surgery proves to be an effective therapy for correcting midfacial hypoplasia and skeletal mandibular protrusion caused by Apert syndrome.

Rho-associated protein kinase and cyclophilin a are involved in inorganic phosphate-induced calcification signaling in vascular smooth muscle cells.

Arterial calcification, a risk factor of cardiovascular events, develops with differentiation of vascular smooth muscle cells (VSMCs) into osteoblast-like cells. Cyclophilin A (CypA) is a peptidyl-prolyl isomerase involved in cardiovascular diseases such as atherosclerosis and aortic aneurysms, and rho-associated protein kinase (ROCK) is involved in the pathogenesis of vascular calcification. CypA is secreted in a ROCK activity-dependent manner and works as a mitogen via autocrine or paracrine mechanisms in VSMCs. We examined the involvement of the ROCK-CypA axis in VSMC calcification induced by inorganic phosphate (Pi), a potent cell mineralization initiator. We found that Pi stimulated ROCK activity, CypA secretion, extracellular signal-regulated protein kinase (ERK) 1/2 phosphorylation, and runt-related transcription factor 2 expression, resulting in calcium accumulation in rat aortic smooth muscle cells (RASMCs). The ROCK inhibitor Y-27632 significantly suppressed Pi-induced CypA secretion, ERK1/2 phosphorylation, and calcium accumulation. Recombinant CypA was found to be associated with increased calcium accumulation in RASMCs. Based on these results, we suggest that autocrine CypA is mediated by ROCK activity and is involved in Pi-induced ERK1/2 phosphorylation following calcification signaling in RASMCs.

Trichoblastic infundibular cyst should be renamed infundibular cyst with unique papillary projections.

Trichoblastic infundibular cyst (TBIC) was previously reported as a unique keratinous cystic lesion, which was characterized by the papillary projections of follicular germinative-like cells emanating from the cyst wall. Here, we report three additional cases of this cyst and discuss the pathogenesis of this unique entity. In all cases, a unilocular cyst contained keratin, and the cyst wall was composed of squamous epithelium. A number of cords and papillary projections emanated from the basal layer of the cyst wall. They were composed of cells with large nuclei and scant cytoplasm arranged in a peripheral palisade. Immunohistochemically, anti-cytokeratin 15, anti-cytokeratin 20, and anti-epithelial cell adhesion molecule antibodies were negative. Thus, these cells resembled follicular germinative cells or sebaceous mantle morphologically, but we failed to prove the differentiation immunohistochemically. The cyst was surrounded by fibrotic stroma and inflammatory cells, suggesting previous rupture of the cyst. We speculate that the cells of the projections possibly differentiate into the mantle rather than follicular germinative cells, even though we could not provide sufficient immunohistochemical evidence. We also suggest that they may be induced by special reaction to fibrohistiocytic stroma surrounding the infundibular cyst. Therefore, TBIC should be renamed infundibular cyst with unique papillary projections.

Analysis of Risk Factors Associated With Drooping Deformity After Lower Eyelid Reconstruction: A Newly Developed Drooping Index.

BACKGROUND: Lower eyelid reconstruction is challenging because of the risk of severe postreconstruction deformities of the lower eyelid, such as drooping, entropion, and ectropion. However, the risk factors for these postreconstruction deformities are unclear. The present study aimed to quantify the drooping deformity of the lower eyelid after reconstruction using a cheek rotation flap and to identify risk factors associated with postreconstruction deformities. METHODS: Our study group included 28 patients who underwent full-thickness lower eyelid reconstruction using a cheek rotation flap for anterior lamella reconstruction. We developed the drooping index to classify postreconstruction outcomes as good (index <1.2), fair (index between 1.2 and 1.5), and poor (index >1.5). We identified risk factors for a drooping deformity using univariate analyses (Mann-Whitney U or Spearman rank correlation, depending on data distribution). RESULTS: Overall, the drooping index ranged between 1.0 and 2.11, with an average value of 1.3. A good outcome was obtained in 11, a fair outcome in 12, and a poor outcome in 5 patients. Clinically severe ectropion was observed in five of the 17 patients in the fair and poor outcome groups, with four of these patients requiring revision surgery. Risk factors for postreconstruction drooping deformity included medial location of the tumor, resection involving more than 50% of the horizontal width of the lower eyelid, and dissection of subcutaneous tissue of the cheek extending below the zygomatic arch. CONCLUSIONS: A cheek rotation flap provides satisfactory outcomes for full-thickness reconstruction of the lower eyelid. Extension of dissection of subcutaneous tissue of the cheek below the zygomatic arch increases the risk of postsurgical drooping deformity. Our drooping index provides a quantitative measure of drooping deformity and is clinically useful to classify outcomes.

Pectoralis major turnover flap based on thoracoacromial vessels for sternal dehiscence.

BACKGROUND: Reconstruction of long and deep sternal defects has been challenging. The pectoralis major can be used in the conventional turnover method that requires the internal thoracic vessel. We developed a new turnover pectoralis major flap based on thoracoacromial vessels. The purpose of this report is to present results from 14 patients. METHODS: Fourteen patients with a mean age of 73.6 years (range, 53-83 years) who had sternal defects underwent reconstruction via this procedure. The defects were caused by mediastinitis and sternal osteomyelitis in six and eight patients, respectively. The internal thoracic artery (ITA) was harvested in two patients. The mean defect size was 2.4 × 15.5 cm (ranging 1-4.3 × 13-18 cm). After elevation of the lateral border of the muscle and ligation of the third to fifth perforators from ITA, the lateral side was turned over and the medial lower portion of the flap was additionally transplanted to the defect. RESULTS: The mean flap size was 10.7 × 18 cm (ranging 9-13 × 15-21 cm). For 11 patients, defects healed without any complications. Discharge after flap reconstruction was observed in three patients, two of whom were managed using conservative treatments. Only one patient who needed additional debridement required transplantation of the contralateral pectoral major flap. CONCLUSIONS: This muscle flap is nourished primarily by the thoracoacromial vessel. The long length and large volume of the muscle flap could be successfully turned over with this procedure even in patients that had their internal thoracic artery sacrificed.

The Japanese registry for surgery of ischial pressure ulcers: STANDARDS-I.

OBJECTIVE: To clarify the surgical indications and the appropriate perioperative management of ischial pressure ulcers (PUs). METHOD: A two-year prospective, nationwide registry study was carried out across 26 medical institutions in Japan. All participating institutions managed ischial PUs according to the standardisation of total management and surgical application for the refractory decubitus (STANDARDS-I) perioperative protocol. Analysis was conducted on a range of clinically or statistically important variables for the achievement of primary or secondary endpoints: complete wound healing and hospital discharge at three months, and complete wound healing at one month after surgery, respectively. RESULTS: A total of 59 patients took part in the study. All patients underwent surgery for ischial PUs during the study period. Patients who had achieved the primary endpoint had a higer preoperative functional independence measurement (FIM score), a higher 'G' score in the DESIGN-R scale and were more likely to have healed by primary intention. Patients who had achieved the secondary endpoint were more likely to have spastic paralysis, preoperative physiotherapy and localised infection of the wound, among other variables. CONCLUSION: This survey suggests that preoperative physiotherapy increases the speed of wound healing, and good granulation of the wound bed preoperatively increases the likelihood of woundless discharge from hospital, whereas the existence of comorbidities negatively influences the likelihood of woundless discharge from hospital. The study also suggests that the existence of spastic paralysis, preoperative infection of the wound, or surgical reduction of the ischial tubercle speeds up the healing of the wound. However, the wound failed to heal significantly more often in patients with increasing white blood cell count after surgery.

Topical application of nitrosonifedipine, a novel radical scavenger, ameliorates ischemic skin flap necrosis in a mouse model.

Ischemic skin flap necrosis can occur in random pattern flaps. An excess amount of reactive oxygen species is generated and causes necrosis in the ischemic tissue. Nitrosonifedipine (NO-NIF) has been demonstrated to possess potent radical scavenging ability. However, there has been no study on the effects of NO-NIF on ischemic skin flap necrosis. Therefore, they evaluated the potential of NO-NIF in ameliorating ischemic skin flap necrosis in a mouse model. A random pattern skin flap (1.0 × 3.0 cm) was elevated on the dorsum of C57BL/6 mice. NO-NIF was administered by topical injection immediately after surgery and every 24 hours thereafter. Flap survival was evaluated on postoperative day 7. Tissue samples from the skin flaps were harvested on postoperative days 1 and 3 to analyze oxidative stress, apoptosis and endothelial dysfunction. The viable area of the flap in the NO-NIF group was significantly increased (78.30 ± 7.041%) compared with that of the control group (47.77 ± 6.549%, p < 0.01). NO-NIF reduced oxidative stress, apoptosis and endothelial dysfunction, which were evidenced by the decrease of malondialdehyde, p22phox protein expression, number of apoptotic cells, phosphorylated p38 MAPK protein expression, and vascular cell adhesion molecule-1 protein expression while endothelial nitric oxide synthase protein expression was increased. In conclusion, they demonstrated that NO-NIF ameliorated ischemic skin flap necrosis by reducing oxidative stress, apoptosis, and endothelial dysfunction. NO-NIF is considered to be a candidate for the treatment of ischemic flap necrosis.

Two-stage surgery for hidradenitis suppurativa: staged artificial dermis and skin grafting.

BACKGROUND: Hidradenitis suppurativa is a chronic and often refractory skin disease that can require radical excision of the full layer of fatty tissue under the lesion. Closure using a split-thickness skin graft often results in depression deformity and lack of tissue flexibility. We have developed a two-stage procedure to preserve fatty tissue during radical excision and apply an artificial dermis graft, and we have performed this procedure in 18 patients (33 lesions). OBJECTIVE: To describe our two-stage procedure and report results of the procedure in our patient series. METHODS: In the first step, all diseased skin including the superficial subcutaneous fatty tissue is excised; normal deep subcutaneous fatty tissue is preserved. Artificial dermis is then grafted to the preserved fatty tissue. Two weeks later, split-thickness skin grafts are applied to the skin defects. We evaluated graft success, any recurrence, and postoperative appearance in our patients, who were followed up for 8 to 36 months. RESULTS: All 32 skin grafts were successful. There was only one recurrence, which was treated using reoperation, and postoperative appearances were good. CONCLUSIONS: Our new procedure incorporating artificial dermis appears to be a good treatment option for advanced hidradenitis suppurativa.

Functional outcomes of reconstructive flap surgery for soft tissue sarcoma: Long-term outcomes of functional restoration using innervated muscle transplantation.

Functional outcomes associated with prognostic factors and innervated muscle transplantation after wide soft tissue sarcoma resection remain unclear. We retrospectively examined the functional outcomes of reconstructive flap surgery for soft tissue sarcoma. Twenty patients underwent innervated muscle transplantation with pedicled or free flaps for functional reconstruction of resected muscles. Thirteen latissimus dorsi muscles and one vastus lateralis muscle combined with an anterolateral thigh flap were transferred as free flaps using the epi-perineural suture technique. Six latissimus dorsi muscles were transferred as pedicled flaps with neural continuity. Postoperative functional outcomes were assessed using the Musculoskeletal Tumor Society (MSTS) scores for the upper and lower extremities of 22 and 24 patients, respectively. The mean MSTS score for all patients was 82.3 at 12 months postoperatively. The mean scores for patients who underwent reconstruction with pedicled and free flaps were 89.2 and 77.1, respectively. The MSTS scores for the lower extremity, tumor size ≥5 cm, and free flap reconstruction were significantly lower than those for the upper extremity, tumor size <5 cm, and pedicled flap reconstruction (P = 0.02, 0.37, and 0.008, respectively). The postoperative MSTS score for innervated muscle transplantation was 76.7 at 12 months and was significantly higher (83.7) at 24 months (P = 0.003). Functional outcomes were significantly associated with tumor location, tumor size, and reconstructive flap type based on the MSTS scores. Innervated muscle transplantation improved functional outcomes at 24 months postoperatively via sufficient recovery of the innervated muscle, not the compensatory recovery of the remaining muscle.

Risk factors for early wound dehiscence by surgical site infection after pressure ulcer surgery.

AIMS: The most common postoperative complication when treating a pressure ulcer with a flap or primary closure is early wound dehiscence. In this study, we aimed to investigate the cause of early wound dehiscence and its associated risk factors. Early wound dehiscence was defined as the wound dehiscence within the post operation period where no weight or tension is applied to the wound. METHODS: We conducted a retrospective study of 40 patients with pressure ulcers (69 sites). We calculated the significant difference in the incidence of wound dehiscence between the groups for the following 15 factors : age, obesity, emaciation, diabetes mellitus, smoking, ulcer site, musculocutaneous flap, methicillin-resistant Staphylococcus aureus, presence of two or more types of bacteria, albumin level, C-reactive protein level, white blood cell count, hemoglobin level, operative time, and ulcer size. RESULTS: Bacteria were detected in all wounds with early dehiscence, which was found in 28 (40.6%) of the 69 cases. C-reactive protein level, albumin level, musculocutaneous flap, and operative time were found to be risk factors for early wound dehiscence using the χ2-test and t-test. (P?=?0.011, 0.045, 0.018, and 0.003, respectively). CONCLUSION: The cause of dehiscence was considered to be surgical site infection. C-reactive protein level, albumin level, musculocutaneous flap, and operative time may be risk factors of the occurrence of early wound dehiscence. J. Med. Invest. 70 : 101-104, February, 2023.

Cyclical Stretching Induces Excess Intracellular Ca2+ Influx in Human Keloid-Derived Fibroblasts In Vitro.

BACKGROUND: The incidence of keloids is higher in the case of darker skin. It is more common in the parts exposed to stretching (thorax, abdomen, and joints). Cyclical stretching reportedly induced each Ca2+ spike through differential mechanosensitive channels in human synovial and dermal fibroblasts. Therefore, the authors hypothesized that cyclical stretching also induces a specific Ca2+ spike in keloid-derived fibroblasts. METHODS: This in vitro study compared the intracellular calcium dynamics induced by cyclical stretching between control (human dermal fibroblasts) and keloid (human keloid-derived fibroblasts) groups. Each group was exposed to two-dimensional stretch using an originally developed stretch microdevice. Intracellular Ca2+ was observed for 5 minutes, including 30 seconds of baseline, under a fluorescent confocal laser microscope. The intracellular Ca2+ concentration was evaluated every 0.5 second using the fluorescence intensity ratio. A positive cellular response was defined as a rise of the ratio by greater than or equal to 20%. The normal response cutoff value was determined by receiver operating characteristic analysis. RESULTS: The keloid groups were significantly more responsive than the control groups (15.7% versus 8.2%; P = 0.029). In the cellular response-positive cells, the keloid groups reached significantly higher intracellular Ca2+ concentration peaks than the control groups (2.20 versus 1.26; P = 0.0022). The cutoff value was 1.77, and 10.4% of the keloid-derived fibroblasts exhibited a hyper-Ca2+ spike above the normal range. CONCLUSIONS: Keloid-derived fibroblasts with a hyper-Ca2+ spike might constitute a keloid-specific subpopulation. Hereafter, the authors will study whether the normalization of excessive intracellular Ca2+ concentration leads to keloid treatment in vivo. CLINICAL RELEVANCE STATEMENT: This study result provided a clue to the onset mechanism of keloids, which the authors hope will lead to the development of new therapy in the future.

Impact of COVID-19 pandemic on the care of severe burns in Japan: Repeated survey of specialized burn care facilities.

BACKGROUND: The spread of coronavirus disease 2019 (COVID-19), which began in 2020, has had a major impact on healthcare systems. The spread of COVID-19 has been reported to have affected the readiness to treat patients with burns worldwide. However, the existing reports have evaluated burn care status within a limited time period during the pandemic, and no report clarifies the change in the impact of infection status on burn care from the beginning of the pandemic to the present. METHODS: Japanese Society for Burn Injuries-accredited burn care facilities were surveyed using questionnaires on April 9-23, 2020; June 23-July 6, 2020; July 9-21, 2021; and January 21-31, 2022. Differences between groups were evaluated using Friedman's test or Bonferroni's multiple comparison test, as appropriate. RESULTS: From the 103 facilities included in the study, we received 85, 55, 56, and 58 responses in the first, second, third, and fourth surveys, respectively. We could continuously observe 34 facilities. The rate of acceptance of patients with severe burns improved significantly over time (P < 0.05). However, in the second and third surveys, there was an increase in the number of respondents who did not accept patients with burns irrespective of COVID-19 status. CONCLUSIONS: The number of facilities treating patients with burns who have COVID-19 is increasing; however, COVID-19 care may negatively impact routine burn care. It is necessary to continuously examine medical resource allocation through methods such as information sharing by academic societies.

Effect of joint limitation and balance control on gait changes in diabetic peripheral neuropathy.

Aims: This study analyzed the gait patterns of diabetic peripheral neuropathy (DPN) patients and changes in the center of mass sway to prevent the formation and recurrence of foot ulcers. Methods: Forty-two subjects were divided into the diabetes mellitus (DM), DPN, and diabetic foot ulcer (DFU) groups. We measured the range of motion (ROM) of the lower limb joints in the resting position and the center of mass sway in the standing position. Joint angles, ROM during walking, and distance factors were evaluated. Results: In the DFU group, ROM limitation during walking was detected at the knee joint, and functional and ROM limitations were found at the ankle joint. The step length ratio and step width in the DFU group were significantly lower and higher than those in the DM group, respectively. The sway distances in the DFU group were greater than those in the DM and DPN groups. Conclusions: Functional joint limitations and gait changes due to the decreased ability to maintain the center of gravity were observed in the DFU group. As DPN progressed, the patients' gait became small, wide, and shuffled. Thus, supporting joint movement during walking may help reduce the incidence and recurrence of foot ulcers. Supplementary Information: The online version contains supplementary material available at 10.1007/s13340-023-00647-9.

Radiographic Study Evaluating Perforator Vessels in the Ischiorectal Fossa for Safe Elevation of Island Flaps.

Perforator flaps based on the ischiorectal fossa (IRF) (ie, internal pudendal artery perforator flaps) are useful for perineal reconstruction. The three-dimensional characterization of perforator arteries in the IRF remains unclear, as the IRF contains thick adipose tissue as well as organs, such as the rectum, vagina, and urethra. This study aimed to evaluate perforators in the IRF to guide the safe elevation of skin flaps designed based on the IRF. Methods: IRF vessels were examined in 200 bilateral computed tomography angiography scans performed in 100 patients. We examined branching patterns arising from the internal iliac artery and the origins of the skin perforators in the IRF. Results: The branching patterns of the internal iliac artery were divided into three groups: perforators derived exclusively from the internal pudendal artery (78%), perforators derived from the internal pudendal artery and the inferior gluteal artery (18%), and perforators derived exclusively from the inferior gluteal artery (4%). The average number of perforators in the IRF was 1.5 ± 0.7. The number of perforators was significantly higher in women than in men. The perforator arteries were found exclusively around the medial and dorsal sides of the ischial tuberosity. Conclusions: We found that perforators in the IRF were stable. All cases had more than one skin perforator, which was mainly derived from the internal pudendal artery. Although perforators cannot be identified during flap elevation because the fatty tissue in the IRF is very thick, physicians must focus on preserving the perforator-containing fatty tissue around the ischial tuberosity.

Relationship between fluctuations in skin perfusion pressure values and wound healing in patients with chronic limb-threatening ischemia undergoing hemodialysis.

Background : Patients with chronic limb-threatening ischemia are often on hemodialysis. It is unclear which skin perfusion pressure (SPP) values, i.e., those measured immediately after hemodialysis on a hemodialysis day or those measured on a non-hemodialysis day, reflect the actual wound healing course in chronic limb-threatening ischemia. Methods : Eighteen patients undergoing hemodialysis (49 measurements) who were treated for leg ulcers due to critical limb ischemia were included in the study. The SPP values were divided into two groups : those measured immediately after hemodialysis (HD day group) and those measured on non-hemodialysis days (non-HD day group). The wound healing outcomes were investigated. The cutoff SPP value for predicting wound healing was set to ≥ 35 mmHg. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SPP in each group were measured. The relationship between SPP and blood pressure was analyzed by regression analysis. Results : Significant differences were observed in the positive predictive value (HD day : 100%, non-HD day : 50% ; P = 0.002), The correlation coefficient was 0.698 in the HD day group and 0.292 in the non-HD day group. Diastolic blood pressure had a significant effect on SPP (P = 0.039). Conclusions : The measurements are best taken immediately after hemodialysis for more accuracy. J. Med. Invest. 69 : 294-298, August, 2022.

Production of cell-enclosing hollow-core agarose microcapsules via jetting in water-immiscible liquid paraffin and formation of embryoid body-like spherical tissues from mouse ES cells enclosed within these microcapsules.

We developed agarose microcapsules with a single hollow core templated by alginate microparticles using a jet-technique. We extruded an agarose aqueous solution containing suspended alginate microparticles into a coflowing stream of liquid paraffin and controlled the diameter of the agarose microparticles by changing the flow rate of the liquid paraffin. Subsequent degradation of the inner alginate microparticles using alginate lyase resulted in the hollow-core structure. We successfully obtained agarose microcapsules with 20-50 microm of agarose gel layer thickness and hollow cores ranging in diameter from ca. 50 to 450 microm. Using alginate microparticles of ca. 150 microm in diameter and enclosing feline kidney cells, we were able to create cell-enclosing agarose microcapsules with a hollow core of ca. 150 microm in diameter. The cells in these microcapsules grew much faster than those in alginate microparticles. In addition, we enclosed mouse embryonic stem cells in agarose microcapsules. The embryonic stem cells began to self-aggregate in the core just after encapsulation, and subsequently grew and formed embryoid body-like spherical tissues in the hollow core of the microcapsules. These results show that our novel microcapsule production technique and the resultant microcapsules have potential for tissue engineering, cell therapy and biopharmaceutical applications.

Risk factors for delayed healing at the free anterolateral thigh flap donor site.

BACKGROUND: The free anterolateral thigh (ALT) flap has been widely used for various kinds of reconstructions. However, delayed healing at the donor site occasionally occurs due to wound dehiscence or the partial loss of grafted skin at the donor site. The aim of the present study was to identify reliable predictive factors for delayed healing at the donor site after the harvest of a free ALT flap. METHODS: This study included 52 patients who underwent reconstructive procedures using free ALT flaps. The delayed healing group included patients with wounds at the donor site that had not healed over 3 weeks after surgery, and the normal healing group included patients who showed wound healing within 3 weeks after surgery. Multivariate logistic regression models were created to identify the risk factors for delayed healing at the ALT flap donor site. RESULTS: Among the 52 patients, 24 (46.2%) showed delayed healing at the donor site, and 6 patients required additional operative treatment. A high preoperative body mass index (BMI), smoking, and skin grafting were found to be significantly associated with delayed healing at the ALT donor site. Of the 37 patients who underwent skin grafting, 23 (62%) experienced delayed healing at the donor site. CONCLUSIONS: A high preoperative BMI, smoking, and skin grafting were risk factors for delayed healing at the free ALT donor site. Skin grafting at the ALT donor site should be avoided in patients with a high BMI or a habit of smoking.