Proximal Skin Research Articles

The clinical application and anatomical analysis of proximal peroneal artery perforator in free fibula flap based on CTA

BackgroundThe vascularized free fibular flap is increasingly recognized as the standard technique for the repair of complex soft tissue and hard tissue defects in oral and maxillofacial surgery. Conventionally, the vascular supply to the skin island is derived from the distal perforators of the peroneal artery. However, complications may arise if these distal perforators are either absent or damaged during surgical procedures, highlighting the necessity to employ the proximal peroneal perforators as an alternative. This study aims to investigate the anatomical characteristics—including the presence, distribution, and origin—of proximal peroneal perforators through computed tomography angiography (CTA) prior to surgical intervention. A secondary objective is to confirm their viability when distal perforators are unavailable or when dual-skin paddles are needed.MethodsA comprehensive review was conducted involving 50 patients who underwent CTA examinations. Three-dimensional reconstruction of DICOM data was utilized to document the presence, quantity, location, and variations of proximal perforators. Relative positions of the origin points were measured, and the distances from these points to the fibula were calculated. Additionally, 11 studies were included in which a proximal perforator was successfully used to prepare a free fibula chimeric myocutaneous flap for the reconstruction of maxillofacial defects.ResultsAmong the 100 lower limbs evaluated, a successful identification rate of 98% for proximal perforators was achieved via CTA. Of those identified, 70% were found to originate from the fibular artery, 22% branched concurrently with it, and 8% emerged prior to the point of emergence of the fibular artery. Analysis through curve fitting indicated that the origin points of proximal perforators were predominantly located approximately 13.17 mm below the origin of the fibular artery, with their endpoints projecting about 123.9 mm below the fibular head.ConclusionsThe high prevalence of proximal peroneal perforators identified in this population, along with their relatively stable anatomical positions, suggests their significant surgical potential. In scenarios where the distal peroneal perforator is absent or suffers intraoperative injury, the proximal peroneal perforator can serve as a reliable alternative for preparing a free fibula osteal flap combined with a proximal peroneal perforator skin paddle.

Ex-vivo evaluation of a percutaneous thread technique to palmar/plantar annular desmotomy in horses

Palmar/plantar annular desmotomy (PAD) is a surgical procedure to mitigate pain, lameness, and other clinical manifestations of annular ligament syndrome. This study aimed to describe a minimally invasive technique for PAD and evaluate potential damage to adjacent structures in 15 cadaveric limbs from sound horses (forelimb = 6 and hindlimb = 9). A 6 USP polyglycolic acid thread was positioned around the palmar/plantar annular ligament (PAL) on both sides of the limbs through two incisions (proximal and distal to PAL) through the digital sheath and subcutaneous tissue. Kelly forceps, Gerlach or Obwegeser needles were used to thread placement. A back-and-forth motion allowed the thread to cut the ligament until it exited through the proximal skin incision, and the time was registered. The degree of PAL section and tissue injuries were evaluated. The section of the ligament was complete in all limbs. However, 30% (10/30) of the procedures produced iatrogenic injuries on adjacent structures regardless of the instrument used (p > 0.1). There was a higher frequency of lesions in the neurovascular bundle (NVB) on the medial side regardless of the limb (p = 0.068). The odds of injury in the NVB were correlated to side (lateral or medial (p = 0.042) and limb (hind or forelimb) (p = 0.065) by logistic regression. The Gerlach needle had a shorter execution time than the Kelly forceps (p = 0.003). The percutaneous approach to PAD in specimens was practical, quick, and easy to perform. However, this posed a potential chance of iatrogenic trauma to the surrounding tissue. Although they are all reasonable options, the Obwegeser needle was more efficient for applying the thread than the others.

Vascular and nerve biomarkers in thigh skin biopsies differentiate painful from painless diabetic peripheral neuropathy.

Identifying distinct mechanisms and biomarkers for painful diabetic peripheral neuropathy (DPN) is required for advancing the treatment of this major global unmet clinical need. We previously provided evidence in calf skin biopsies that disproportion between reduced sensory small nerve fibers and increased blood vessels may distinguish painful from non-painful DPN. We proposed that overexposure of the reduced nerve fibers in DPN to increased hypoxemia-induced vasculature and related algogenic factors, e.g., nerve growth factor (NGF), leads to neuropathic pain. To further investigate this proposed mechanism, we have now studied more proximal thigh skin biopsies, to see if the same disproportion between increased vasculature and decreased nerve fibers generally differentiates painful DPN from painless DPN. A total of 28 subjects with type 2 diabetes (T2DM) and 13 healthy volunteers (HV) underwent detailed clinical and neurophysiological assessments, based on the neuropathy composite score of the lower limbs [NIS(LL)] plus 7 tests. T2DM subjects were subsequently divided into three groups: painful DPN (n = 15), painless DPN (n = 7), and no DPN (n = 6). All subjects underwent skin punch biopsy from the upper lateral thigh 20 cm below the anterior iliac spine. Skin biopsies showed decreased PGP 9.5-positive intraepidermal nerve fiber (IENF) density in both painful DPN (p < 0.0001) and painless DPN (p = 0.001). Vascular marker von Willebrand Factor (vWF) density was markedly increased in painful DPN vs. other groups, including painless DPN (p = 0.01). There was a resulting significant decrease in the ratio of intraepidermal nerve fiber density to vasculature and PGP9.5 to vWF, in painful DPN vs. painless DPN (p = 0.05). These results were similar in pattern to those observed in these HV and T2DM groups previously in distal calf biopsies; however, the increase in vWF was much higher and nerve fiber density much lower in the calf than thigh for painful DPN. Thigh skin vWF density was significantly correlated with several metabolic (waist/hip ratio, HbA1c), clinical (e.g., pain score), and neurophysiological measures. This study supports our proposal that increased dermal vasculature, and its disproportionate ratio to reduced nociceptors, may help differentiate painful DPN from painless DPN. This disproportion is greater in the distal calf than the proximal thigh skin; hence, neuropathic pain in DPN is length-dependent and first localized to the distal lower limbs, mainly feet.

Is the clavicla pro humero a reliable reconstruction for paediatric proximal humerus sarcomas?

The proximal humeral reconstruction is challenging. This study aims to investigate the survival, function and complications of clavicla pro humero (CPH) for pediatric proximal humeral reconstruction. A retrospective cohort study was conducted on eight patients (4 males, and 4 females) who underwent clavicla pro humero reconstruction between January 2009 and December 2020 in our institution. The average age was 10.4 ± 2.7 years (range, 6 to 14 years). The functional outcomes were assessed by the Musculoskeletal Tumor Society Score (MSTS-93), the Toronto Extremity Salvage Score (TESS), the American Shoulder and Elbow Surgeons (ASES) score and the range of motion (ROM) of the shoulder. The complications and overall survivorship of clavicla pro humero were recorded in the follow-up. The mean follow-up of all patients was 54.6 ± 23.9 months (range, 24 to 84 months) and 73.3 ± 8.5 months (range, 72 to 84 months) in all survivors. All patients had a bone union at an average of 3.8 months after the initial procedure. Only one patient had no complications in the follow-up. The most common complications were clavicle fracture (87.5%, 7/8), followed by pseudarthrosis (62.5%, 5/8), proximal clavicle osteolysis (37.5%, 3/8) and skin flap necrosis (12.5%, 1/8). The average MSTS-93 score was 79% (range, 73-86%), the average TESS was 82% (range, 76-86%) and the average ASES was 70% (68-73%), respectively. The clavicla pro humero procedure provides rapid bone union but has a high complication rate. Therefore, we do not recommend this technique as a routine surgical procedure for paediatric proximal humeral reconstruction when other methods are available. level IV therapeutic study.

Reconstruction of Multiple Lip and Facial Defects With Bipaddle and Sensate Radial Forearm Free Flap.

Free flaps and their modifications are used to reconstruct multiple large defects in the lip and face. In this study, we present our results on the reconstruction of these defects using bipaddle and sensate free radial forearm-palmaris longus flaps and subsequent revision surgeries. Patient medical records of 11 patients with a mean age of 63.9 ± 12.8 years were retrospectively reviewed. Functional oral competence, lip cosmetics, lip sensation, and donor forearm scars were evaluated using the drooling rating scale, visual analog scale, Semmes Weinstein Monofilament test, and patient and observer scar assessment scale, respectively. The mean dimensions of distal and proximal skin paddles of bipaddle free radial forearm-palmaris longus flaps were 12.7 ± 9.9 and 20.5 ± 3.8 cm2. Mean lengths of the bridge and proximal pedicles were 4.7 ± 1.6 and 5.5 ± 0.7 cm. All the flaps survived. No drooling was observed in the 2 patients without lower lip defects. The mean drooling scores of the 9 patients with lower lip defects were statistically different (Analysis of Variance, pANOVA < 0.00001) at 3, 6, 9, and 12 months postoperatively. The differences between 3 and 12 months were the most significant (pANOVA < 0.00001, pTUKEY < 0.000001). The lip sensation and drooling scores showed a strong positive correlation (r = 0.8504). All patients were able to speak fluently, drink fluid without leakage, and blow a balloon easily. All patients and observers were satisfied with the lip cosmetics, with no significant difference between satisfaction scores (P = 0.087615).There was a statistically significant difference (P < 0.00001) between mean sensation scores of surrounding healthy lip (2.94 ± 0.27) and free flaps (4.15 ± 0.4). All the donor scars healed uneventfully.

Enhanced conductive body heat loss during sleep increases slow-wave sleep and calms the heart

Substantial evidence suggests that the circadian decline of core body temperature (CBT) triggers the initiation of human sleep, with CBT continuing to decrease during sleep. Although the connection between habitual sleep and CBT patterns is established, the impact of external body cooling on sleep remains poorly understood. The main aim of the present study is to show whether a decline in body temperatures during sleep can be related to an increase in slow wave sleep (N3). This three-center study on 72 individuals of varying age, sex, and BMI used an identical type of a high-heat capacity mattress as a reproducible, non-disturbing way of body cooling, accompanied by measurements of CBT and proximal back skin temperatures, heart rate and sleep (polysomnography). The main findings were an increase in nocturnal sleep stage N3 (7.5 ± 21.6 min/7.5 h, mean ± SD; p = 0.0038) and a decrease in heart rate (− 2.36 ± 1.08 bpm, mean ± SD; p < 0.0001); sleep stage REM did not change (p = 0.3564). Subjects with a greater degree of body cooling exhibited a significant increase in nocturnal N3 and a decrease in REM sleep, mainly in the second part of the night. In addition, these subjects showed a phase advance in the NREM-REM sleep cycle distribution of N3 and REM. Both effects were significantly associated with increased conductive inner heat transfer, indicated by an increased CBT- proximal back skin temperature -gradient, rather than with changes in CBT itself. Our findings reveal a previously far disregarded mechanism in sleep research that has potential therapeutic implications: Conductive body cooling during sleep is a reliable method for promoting N3 and reducing heart rate.

Fibular free flap with proximal perforator skin paddle due to aberrant anatomy — a case report

BackgroundThe fibular free flap is considered one of the most valuable options for mandible reconstruction. A perforator flap has gained widespread acceptance in oral and maxillofacial reconstruction. Typically, the fibula flap is obtained primarily with the distal perforator due to its reliable blood supply, with less attention given to the proximal perforators during the harvesting process. Normally, the distal perforator of the fibula exhibits stability and shows limited anatomical variations. However, there have been reported cases in which the distal perforator is absent. At times, these vascular abnormalities remain undetectable through Doppler examination or preoperative angiography evaluation. Therefore, this case details the experience of encountering the rare event of vascular abnormality in oral cancer surgery.Case presentationThis article reports the case of a patient who presented with a congenital absence of the distal perforator in the peroneal artery, attributed to a vascular abnormality. Additionally, we provide a review of the concept of utilizing the proximal perforator as an alternative approach in the flap harvesting process.ConclusionsWhile the distal perforator of the peroneal artery is typically utilized for fibula free flap procedures, surgeons must remain cognizant of the potential for its absence due to aberrant anatomy. Recognizing an alternative approach in such cases can be pivotal for precise surgical planning and favorable outcomes in oral and maxillofacial reconstruction

Anatomic feasibility study of a sartorius myocutaneous flap with a distally based pedicle and proximal skin paddle

IntroductionWe conducted an anatomic feasibility study of a sartorius myocutaneous flap with a distally based pedicle and proximal skin paddle to cover soft tissue defects of the knee region. HypothesisA recent anatomic study by Mojalla showed that the sartorius muscle had 2 distinct pedicles, making it possible to isolate this muscle on its distal pedicle and harvest it with a skin paddle. Materials and methodsThis anatomic study was conducted on 10 lower limbs. The 2 criteria assessed were (1) the viability of our proximal skin paddle and (2) the arc of rotation and coverage obtained with this myocutaneous flap. ResultsWe identified 7 proximal skin paddles after the injection of India ink into the distal pedicle of the sartorius muscle. In all cases, the arc of rotation of the flap allowed coverage of the knee region. The mean distance between the inferior edge of the skin paddle and the proximal border of the patella (DBAP) was measured at 13cm, and the mean distance between the superior edge of the flap paddle and the anterior superior iliac spine (DASIS) at 16cm. The average skin paddle size was 14 by 7cm. DiscussionOur anatomic study demonstrated the feasibility of our sartorius flap with a distally based pedicle and proximal skin paddle. This technique may be a viable alternative when using gastrocnemius flaps is not feasible, or the surgeon lacks the microsurgical skills to perform free flaps. Level of evidenceIV; descriptive anatomic study.

Application of short-term analysis of skin temperature variability in prediction of survival in patients with cirrhosis.

Background: Liver cirrhosis is a complex disorder, involving several different organ systems and physiological network disruption. Various physiological markers have been developed for survival modelling in patients with cirrhosis. Reduction in heart rate variability and skin temperature variability have been shown to predict mortality in cirrhosis, with the potential to aid clinical prognostication. We have recently reported that short-term skin temperature variability analysis can predict survival independently of the severity of liver failure in cirrhosis. However, in previous reports, 24-h skin temperature recordings were used, which are often not feasible in the context of routine clinical practice. The purpose of this study was to determine the shortest length of time from 24-h proximal temperature recordings that can accurately and independently predict 12-month survival post-recording in patients with cirrhosis. Methods: Forty individuals diagnosed with cirrhosis participated in this study and wireless temperature sensors (iButtons) were used to record patients' proximal skin temperature. From 24-h temperature recordings, different length of recordings (30 min, 1, 2, 3 and 6h) were extracted sequentially for temperature variability analysis using the Extended Poincaré plot to quantify both short-term (SD1) and long-term (SD2) variability. These patients were then subsequently followed for a period of 12 months, during which data was gathered concerning any cases of mortality. Results: Cirrhosis was associated with significantly decreased proximal skin temperature fluctuations among individuals who did not survive, across all durations of daytime temperature recordings lasting 1hour or more. Survival analysis showcased 1-h daytime proximal skin temperature time-series to be significant predictors of survival in cirrhosis, whereby SD2, was found to be independent to the Model for End-Stage Liver Disease (MELD) score and thus, the extent of disease severity. As expected, longer durations of time-series were also predictors of mortality for the majority of the temperature variability indices. Conclusion: Crucially, this study suggests that 1-h proximal skin temperature recordings are sufficient in length to accurately predict 12-month survival in patients with cirrhosis, independent from current prognostic indicators used in the clinic such as MELD.

Blood pressure, pulse rate, and skin temperature during hot-water bathing in real-world settings among community-dwelling older adults: the HEIJO-KYO Study.

Home hot-tub bathing substantially increases drowning mortality rates among older adults in Japan. Previous laboratory studies on hemodynamic responses during hot-tub bathing have been inconsistent depending on the thermal conditions. Furthermore, real-world hemodynamic changes that occur during bathing remain poorly understood. This study investigated the association between individual thermal states and hemodynamic parameters during hot-tub bathing among community-dwelling older adults. In this cross-sectional study conducted between January 2016 and April 2019, which involved 1,479 older adults (median [range] age, 68 [40-90] years), skin temperature on the abdominal surface was measured every minute. Ambulatory blood pressure and pulse rate were recorded at 15-min intervals for 24 h. Participants underwent simultaneous living room temperature measurements in their homes, and the time and methods of bathing were recorded. Associations between skin temperature and hemodynamic parameters during bathing and between the pre-bath living room temperature and in-bath maximum proximal skin temperature were evaluated using mixed-effects and linear regression models, respectively. A 1 °C increase in skin temperature was significantly associated with a 2.41 mmHg (95% confidence interval [CI]: 2.03-2.79) increase in systolic blood pressure and a 2.99 bpm (95% CI: 2.66-3.32) increase in pulse rate, after adjusting for potential confounders, including age, sex, body mass index, antihypertensive medication use, dyslipidemia, diabetes, and living room and outdoor temperatures. Significant interactions were not observed between sex and skin temperature in relation to systolic blood pressure and pulse rate (P = 0.088 and 0.490, respectively). One standard deviation lower living room temperature before bathing was significantly associated with a 0.41 °C (95% CI: 0.35-0.47) higher maximum skin temperature during bathing. Our findings suggest that pre-bath cold exposure may increase the skin temperature during hot-tub bathing, possibly resulting in excessive hemodynamic changes. This provides a framework for future interventions that utilize pre-bath thermal conditions and bathing environments to prevent bath-related deaths.

Clinical characteristics of juvenile systemic sclerosis in Korea: 31-year single-center study.

To evaluate the clinical and laboratory characteristics, therapeutic drugs, and prognosis of juvenile systemic sclerosis (JSSc) at a single center in Korea. This study was a retrospective analysis of patients with JSSc aged <16 years at disease onset and who were treated at our hospital between January 1992 and April 2023. All patients met the Pediatric Rheumatology European Society/American College of Rheumatology/European League against Rheumatism provisional classification criteria for JSSc, and those with localized scleroderma (morphea) were excluded. Among the 13 patients, proximal skin sclerosis (100%), Raynaud's phenomenon (RP) (84.6%), and sclerodactyly (69.2%) were present at the time of diagnosis. The most common symptom before diagnosis was RP, which was present in 10 patients (76.9%), whereas proximal skin sclerosis was observed in only five patients (38.5%). Thirteen patients had positive anti-nuclear antibody (ANA). At the time of diagnosis, five individuals had findings suggestive of interstitial lung disease (ILD) on a pulmonary function test (PFT) or chest computed tomography (CT), two of whom were asymptomatic. During follow-up, three patients developed ILD, one developed renal dysfunction, one developed heart disease, and none died. This study was the first descriptive analysis of clinical features of JSSc in South Korea. Clinical suspicion is essential for diagnosing JSSc in patients with RP, especially if ANA is positive; however, proximal skin sclerosis, which is crucial for diagnosing JSSc, was unrecognized in the early phase of the disease. PFT should be considered even if a patient is asymptomatic or has normal chest CT.

Capacitive proximity skin for non-contact liquid state measurement of robot grippers with different structures

Handling liquid-filled containers is a frequently encountered yet challenging task for robotics. In this paper, a novel capacitive proximity skin was developed to measure liquid levels before grasping, improving the performance of robotics in application areas like domestic service, manufacturing, healthcare, and food processing. This capacitive proximity skin features a flexible structure that is readily adaptable to a variety of grippers, and it seamlessly integrates with Robot Operating System (ROS)-based control systems. Experiments were performed to compare this proximity skin against non-flexible capacitive proximity sensors, focusing on detection frequency and working distance. The results showed that the capacitive proximity skin achieved data-lossless detection in 0.08 s (12.5 Hz) and contactless measurement of liquid level within 0.7 cm, making it highly suitable for grasping operations. This capacitive proximity skin offers as a versatile solution for robotic applications that involve unsealed liquid-filled containers, and it has the potential for application across a wide range of industries.

Preputial melanoma in a crossbred gelding

Segmental posthetomy (sheath ablation) by removing an extensive circumferential segment of the internal preputial fold and extended proximally to the preputial orifice with subsequent end to end anastomosis of the distal and proximal skin edges was satisfactory as a salvage operation. The excised segment was loaded with heaviest melanotic nodules. The horse regained uneventful normality.

OA15 Missing the wood(-y induration) for the trees

OA15 Missing the wood(-y induration) for the trees

Skin temperature as a predictor of on-the-road driving performance in people with central disorders of hypersomnolence.

Excessive daytime sleepiness is the core symptom of central disorders of hypersomnolence (CDH) and can directly impair driving performance. Sleepiness is reflected in relative alterations in distal and proximal skin temperature. Therefore, we examined the predictive value of skin temperature on driving performance. Distal and proximal skin temperature and their gradient (DPG) were continuously measured in 44 participants with narcolepsy type 1, narcolepsy type 2 or idiopathic hypersomnia during a standardised 1-h driving test. Driving performance was defined as the standard deviation of lateral position (SDLP) per 5 km segment (equivalent to 3 min of driving). Distal and proximal skin temperature and DPG measurements were averaged over each segment and changes over segments were calculated. Mixed-effect model analyses showed a strong, quadratic association between proximal skin temperature and SDLP (p < 0.001) and a linear association between DPG and SDLP (p < 0.021). Proximal skin temperature changes over 3 to 15 min were predictive for SDLP. Moreover, SDLP increased over time (0.34 cm/segment, p < 0.001) and was higher in men than in women (3.50 cm, p = 0.012). We conclude that proximal skin temperature is a promising predictor for real-time assessment of driving performance in people with CDH.

String‐Like Time of Flight Sensor Module for a Collaborative Robot

Collaborative robots, that work alongside humans, will be an indispensable part of the future workforce. Proximity skin sensors on collaborative robots help them avoid collisions with people and other objects. Several skin sensors that fit the shape of the robot surface have been developed. As the shape of each robot varies, developing sensors for each of them is expensive and inefficient. In this study, we propose a string‐like time of flight (ToF) sensor module that can be easily mounted on the surface of a robot. The prototype sensor module consists of six ToF sensors, and each module can be interconnected. The module can detect the distance of an object and its position before making contact. Articulated string‐like modules are wrapped around the surface of the robot to detect objects at a given proximity range around the robot. The movement of the robot can be controlled based on the measurement data obtained by the sensor. Therefore, these proximity skin sensor modules can ensure safety and workability of the robot by preventing unwanted contact between the robot and objects. Thus, the sensor can be used as skin sensors in collaborative robots. © 2023 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

0011 Daily verses circadian amplitude of the distal-proximal skin temperature gradient

Abstract Introduction Sleep, circadian rhythms, and thermoregulatory physiology are highly integrated and impact each other. The daily rhythm in the distal-proximal skin temperature gradient (DPG) is wider/more negative during wakefulness, and narrower/closer to zero during sleep. The circadian rhythm in the DPG is wider during the biological day and narrower during the biological night. Here we aimed to quantify and compare the amplitude of the daily rhythm in the DPG under wakefulness-sleep conditions versus the amplitude of the circadian rhythm in the DPG under sleep deprivation conditions to examine associations and magnitude differences. Methods Eleven [5 females] healthy adults [aged 27.6±10.2y, BMI 23.1±2.2 (mean±SD)] participated. After one week of at-home ambulatory monitoring with 8h per night sleep opportunities at habitual bedtimes, participants were studied in the laboratory for three days under controlled dim light (&amp;lt; 8 lux maximum) and ambient temperature conditions (22-24°C). Participants arrived in the afternoon, were kept awake 4h later than typical and scheduled to a 4h sleep opportunity. The next day, participants were sleep deprived for 28h followed by recovery sleep. Skin temperature was assessed every min with iButtons placed subclavicular (proximal skin temperature) and foot palmar (distal skin temperature). The DPG was calculated as difference between proximal and distal skin temperatures. A three-harmonic regression model was used to fit DPG data and derive daily and circadian rhythm amplitudes, and percent difference in amplitude was calculated. Pearson correlations were calculated between daily and circadian rhythm DPG amplitudes. Results DPG amplitude was significantly greater for daily versus circadian rhythm (p &amp;lt; 0.05). Percent difference analyses showed daily DPG rhythm was 57% larger than circadian DPG rhythm (SD 30%, range 22-134%). A significant correlation was found between daily and circadian rhythm DPG amplitudes (r = 0.71, p&amp;lt; 0.05). Conclusion The amplitudes of daily and circadian rhythms of the DPG are associated, but the daily rhythm amplitude is larger. Additional research is needed to compare the relative importance of daily versus circadian skin temperature amplitudes for sleep and circadian relevant outcomes. Support (if any) CurAegis Technologies Inc., Fundacio Joan Riera I Gubau, Undergraduate Research Opportunities Program University of Colorado Boulder

Osteoderms in a mammal the spiny mouse Acomys and the independent evolution of dermal armor

Osteoderms are bony plates found in the skin of vertebrates, mostly commonly in reptiles where they have evolved independently multiple times, suggesting the presence of a gene regulatory network that is readily activated and inactivated. They are absent in birds and mammals except for the armadillo. However, we have discovered that in one subfamily of rodents, the Deomyinae, there are osteoderms in the skin of their tails. Osteoderm development begins in the proximal tail skin and is complete 6weeks after birth. RNA sequencing has identified the gene networks involved in their differentiation. There is a widespread down-regulation of keratin genes and an up-regulation of osteoblast genes and a finely balanced expression of signaling pathways as the osteoderms differentiate. Future comparisons with reptilian osteoderms may allow us to understand how these structures have evolved and why they are so rare in mammals.

Modified trilobed transposition flap for a distal nasal defect.

Reconstruction of a distal nasal defect is challenging due to poor skin mobility and the potential for nasal alar retraction. A trilobed flap can utilize more mobile proximal skin, increase the total rotational arc, and decrease the tension associated with flap transposition. However, the trilobed flap may not be ideal for distal nasal defects because each flap is designed using immobile skin, which may lead to flap immobility and free margin distortion. To overcome these problems, the base and tip of each flap were extended further from the pivot point than those of the conventional trilobed flap. Herein, we report the use of the modified trilobed flap to treat 15 consecutive cases of distal nasal defects that occurred from January 2013 to December 2019. The mean duration of follow-up was 15.6 months. All flaps survived completely, and satisfactory aesthetic outcomes were achieved. No complications such as wound dehiscence, nasal asymmetry, or hypertrophic scarring were observed. The modified trilobed flap is a simple and reliable treatment for distal nasal defects.

Local Inflammatory Mediators Involved in Neuropathic Pain.

Polyneuropathy (PNP) is a term to describe diseases of the peripheral nervous system, 50% of which present with neuropathic pain. In some types of PNP, pain is restricted to the skin distally in the leg, suggesting a local regulatory process leading to pain. In this study, we proposed a pro-inflammatory pathway mediated by NF-κB that might be involved in the development of pain in patients with painful PNP. To test this hypothesis, we have collected nerve and skin samples from patients with different etiologies and levels of pain. We performed RT-qPCR to analyze the gene expression of the proposed inflammatory pathway components in sural nerve and in distal and proximal skin samples. In sural nerve, we showed a correlation of TLR4 and TNFα to neuropathic pain, and an upregulation of TNFα in patients with severe pain. Patients with an inflammatory PNP also presented a lower expression of TRPV1 and SIRT1. In distal skin, we found a reduced expression of TLR4 and miR-146-5p, in comparison to proximal skin. Our findings thus support our hypothesis of local inflammatory processes involved in pain in PNP, and further show disturbed anti-inflammatory pathways involving TRPV1 and SIRT1 in inflammatory PNP.