Molecular and cellular pruritus mechanisms in the host skin.

Pruritus, also known as itching, is a complex sensation that involves the activation of specific physiological and cellular receptors. The skin is innervated with sensory nerves as well as some receptors for various sensations, and its immune system has prominent neurological connections. Sensory neurons have a considerable impact on the sensation of itching. However, immune cells also play a role in this process, as they release pruritogens. Disruption of the dermal barrier activates an immune response, initiating a series of chemical, physical, and cellular reactions. These reactions involve various cell types, including keratinocytes, as well as immune cells involved in innate and adaptive immunity. Collective activation of these immune responses confers protection against potential pathogens. Thus, understanding the molecular and cellular mechanisms that contribute to pruritus in host skin is crucial for the advancement of effective treatment approaches. This review provides a comprehensive analysis of the present knowledge concerning the molecular and cellular mechanisms underlying itching signaling in the skin. Additionally, this review explored the integration of these mechanisms with the broader context of itch mediators and the expression of their receptors in the skin.

Comparison of the Efficacy of Different Radiofrequency Techniques for the Treatment of Lumbar Facet Joint Pain: Combined with Anatomy.

PURPOSE OF REVIEW: Lumbar facet pain is generally considered to be one of the major causes of chronic low back pain. Each lumbar facet joint is innervated by the medial branch of the posterior spinal nerve from its own level and above. Radiofrequency (RF) of the medial branch of the posterior branch of the spinal nerve is an effective method for the treatment of lumbar facet pain. RF technology is diverse, including traditional radiofrequency (TRF), pulsed radiofrequency (PRF), cooled radiofrequency (CRF), low-temperature plasma radiofrequency ablation (CA), and other treatment methods. The purpose of this paper is to compare the efficacy of different radiofrequency techniques and to analyze the reasons for this in the context of anatomy. RECENT FINDINGS: There have been studies confirming the differences in efficacy of different RF techniques. However, most of the studies only compared two RF techniques, not four techniques, TRF, CRF, PRF, and CA, and did not analyze the reasons for the differences in efficacy. This article reviews the differences in the efficacy of the above four RF techniques, clarifies that the differences are mainly due to the inability to precisely localize the medial branch of the posterior branch of the spinal nerve, analyzes the reasons for the inability to precisely localize the posterior branch of the spinal nerve in conjunction with anatomy, and proposes that the development of RF technology for lumbar facet pain requires more in-depth anatomical, imaging, and clinical studies.

The Diagnostic Value of Carnett's Test with Chronic Abdominal Pain: A Narrative Review.

PURPOSE OF REVIEW: Chronic abdominal wall pain is a poorly recognized cause of chronic abdominal pain, and patients frequently go misdiagnosed despite a battery of medical tests. The Carnett's test is a diagnostic tool used to distinguish between abdominal wall pain and visceral pain. This review synthesizes the current literature on the Carnett's test, merges the viewpoints of diverse writers, and evaluates and reports on the Carnett's test's applicability. RECENT FINDINGS: Several clinical investigations have established the usefulness of the Carnett's test in the diagnosis of chronic abdominal wall pain. Furthermore, the Carnett's test is quite useful in determining the depth of the mass and detecting psychogenic abdominal pain. However, its diagnostic use for acute abdominal pain is limited. The Carnett's test is a simple and safe point-of-care diagnostic technique, with several studies supporting its usefulness. Early detection of abdominal wall pain is critical for chronic abdominal wall pain therapy. Carnett's test is very useful in patients with chronic, unexplained local abdominal discomfort who are compliant and do not have a clear rationale for surgery.

Anatomical Study of the Compositions and Internal Connections of the Chiasma Plantare (Master Knot of Henry): Exploring Its Possible Clinical Impact.

The purposes of this study were to integrate the types of interconnecting fibers among components of the chiasma plantare and to deduce their flexion actions. The chiasma plantare and the long flexor tendons in 52 cadaveric feet (26 left feet and 25 right feet) were dissected and removed via gross anatomic dissection. The connections among the flexor digitorum longus (FDL), flexor hallucis longus (FHL), and quadratus plantae (QP) were then classified and analyzed. The connection between the FHL and FDL was type I in 43 (86%) cases, type III in 2 (4%) cases, and type V in 5 (10%) cases, with the FHL manipulating the first through third toes and the FDL manipulating the first through the fifth toes. The shape of the QP in 28 (56%) cases exhibited a 2-headed QP, and in 22 (44%) cases, a medial-headed QP. The composition of the chiasma plantare was 2 layers in 28 (56%) cases and 3 layers in 22 (44%) cases: 9 (18%) cases were type a, 2 (4%) cases were type b1, and 1 (2%) case each was classified as type b2 and b3. The FHL controlled the second toe in 10 (20%) cases; both the second and third toes in 27 (54%) cases; and the second, third, and fourth toes in 13 (26%) cases. The QP manipulated the third and fourth toes in all cases, the second toe in 38 (76%) cases, and the fifth toe in 11 (22%) cases. These data suggest that such variations might result from tendon transfer. In conclusion, we considered the FDL to be more advanced for the recovery of both the ankle and the forefoot based on this study.

The Analgesic Mechanism and Recent Clinical Application of Erector Spinae Plane Block: A Narrative Review.

Now, the erector spinae plane block (ESPB) is widely used in various thoracolumbar surgeries. It has unique advantages: simple and convenient operation, low safety risks, and reduced opioid use. The ESPB is used in thoracic surgery, abdominal surgery, and spinal surgery. There are also relevant research reports on postoperative analgesia during general anesthesia surgery. This article searches the PubMed and Web of Science databases to find and screen relevant studies on ESPB since 2019 and retrospectively summarizes the current indications of ESPB. The methodological quality of the included studies was assessed using the Cochrane bias risk tool. The results showed that the current research on ESPB generally provides low-level clinical evidence. The complex anatomy of the erector spinae muscles is both responsible for its unique advantages and restricts its development. Few anatomical studies have clearly and completely demonstrated the diffusion relationship of local anesthetics among the anatomical structures of the erector spinal muscles. The uncontrollability of the diffusion plane prevents ESPB from being applied on a wider scale with a high level of evidence. To further clarify the scope of application of ESPB and achieve the best analgesic effect, in the future, we should focus on the unique anatomical course and distribution of the erector spinal muscles and their fascia and nerves. It is necessary to combine anatomical, imaging, and histological methods to obtain high-quality evidence to guide clinical application.

More potential uses of specific perforator flaps in the calf - A cadaveric study on the subdermal vascular structure of the lower leg.

BACKGROUND: The perforator flap has garnered significant interest since its inception due to its advantage of not needing a vascular network at the deep fascial level. Perforator flaps are commonly utilized in different flap transplant surgeries, and the thigh flap is presently the most widely used perforator flap. Is it possible for the calf to replace the thigh as a more suitable site for harvesting materials? Currently, there is a lack of relevant anatomical research. This study aims to address this question from an anatomical and imaging perspective. METHODS: This study used cadavers to observe the branches and courses of perforators on the calf and the distribution of skin branches using microdissection techniques, digital X-ray photography, and micro-computed tomography techniques. RESULTS: The perforators had three main branches: the vertical cutaneous branch, the oblique cutaneous branch, and the superficial fascial branch. The superficial fascial branch traveled in the superficial fascia and connected with the nearby perforators. The vertical and oblique cutaneous branches entered the subdermal layer and connected with each other to create the subdermal vascular network. CONCLUSIONS: We observed an intact calf cutaneous branch chain between the cutaneous nerve and the perforator of the infrapopliteal main artery at the superficial vein site. Utilizing this anatomical structure, the calfskin branch has the potential to serve as a substitute for thigh skin flap transplantation and may be applied to perforator flap transplantation in more locations.

Notch1 signaling contributes to TLR4-triggered NF-κB activation in macrophages.

Macrophages substantially influence the development, progression, and complications of inflammation-driven diseases. Although numerous studies support the critical role of Notch signaling in most inflammatory diseases, there is limited data on the role of Notch signaling in TLR4-induced macrophage activation and interaction of Notch signaling with other signaling pathways in macrophages during inflammation, such as the NF-κB pathway. This study confirmed that stimulation with lipopolysaccharide (LPS), a TLR4 ligand, upregulated Notch1 expression in monocyte/macrophage-like RAW264.7 cells and bone marrow-derived macrophages (BMDMs). LPS also induced increased mRNA expression of Notch target genes Notch1 and Hes1 in macrophages, suggesting that TLR4 signaling enhances activation of the Notch pathway. The upregulation of Notch1, Notch1 intracellular domain (NICD), and Hes1 proteins by LPS treatment was inhibited by DAPT, a Notch1 inhibitor. Additionally, the increased TNF-α, IL-6, and IL-1ß expression induced by LPS was inhibited by DAPT and rescued by jagged1, a Notch1 ligand. Furthermore, suppression of Notch signaling by DAPT upregulated Cylindromatosis (CYLD) expression but downregulated TRAF6 expression, IκB kinase (IKK) α/ß phosphorylation, and subsequently, phosphorylation and degradation of IκB-α, indicating that DAPT inhibited NF-κB activation triggered by TLR-4. Interestingly, DAPT did not inhibit the increased MyD88 expression induced by LPS. Our study findings demonstrate that macrophage stimulation via the TLR4 signaling cascade triggers activation of Notch1 signaling, which regulates the expression patterns of genes involved in pro-inflammatory responses by activating NF-κB. This effect may be dependent on the CYLD-TRAF6-IKK pathway. Thus, Notch1 signaling may provide a therapeutic target against infectious and inflammation-driven diseases.

Anatomical Study of the Accessory Tendon of the Extensor Hallucis Longus Muscle and Its Clinical Application.

BACKGROUD: The accessory tendon of the extensor hallucis longus (ATEHL) muscle is a common abnormal structure, and its clinical significance remains debatable. In this study, we provide the incidence of the ATEHL and characterize its morphological types in Asian cadavers and investigate its clinical applications. METHODS: The tendons from 50 adult cadaveric feet, fixed in 10% formalin, were analyzed. We measured the length and width of both the ATEHL and the extensor hallucis brevis (EHB). RESULTS: All dissected specimens had an ATEHL. The first metatarsophalangeal joint was surrounded by an accessory tendon that inserted onto the joint capsule and the dorsal base of the proximal phalanx. We classified the ATEHL into 3 types based on their directions. Differences in ATEHL type based on sex were not statistically significant. CONCLUSIONS: We found an ATEHL in all cadaveric specimens in this study. We surmise that the ATEHL acts as an antagonist with the EHB when the toe is extending, which might help prevent the occurrence of hallux valgus deformity.

Anatomical basis of a proximal fasciocutaneous extension of the distal-based posterior interosseous flap that allows exclusion of the proximal posterior interosseous artery.

OBJECTIVE: The objective of this study was to provide anatomical information for the repair of small tissue defects in the hand with posterior interosseous artery chain-link perforator flaps, a proximal fasciocutaneous extension of the distal-based posterior interosseous flap, which allows the exclusion of the proximal posterior interosseous artery. METHODS: Fourteen posterior interosseous artery chain-link perforator flaps taken from human cadavers were studied by the following three methods: latex perfusion for microanatomy analysis, denture material and vinyl chloride mixed packing for cast analysis, and latex perfusion for the production of clearance specimens. Statistical analysis was performed on cutaneous perforators coming from the intermuscular septum of the extensor carpi ulnaris and the extensor digitorum communis. A cluster analysis was conducted to determine the overall distribution of perforators. RESULTS: There are two main clusters of perforators at a relative distance of 21% and 48% along the ulnar head-to-lateral epicondyle interval. On average, the posterior interosseous artery extends six cutaneous perforators through the intermuscular septum of the extensor carpi ulnaris and the extensor digitorum communis. Of these six arteries, two are clinically significant perforators (0.5 mm or more in diameter) and are located 6 ± 2 cm proximal to the head of the ulna and 10 ± 1 cm distal to the lateral epicondyle of the humerus. Their mean diameters are 0.5 ± 0.1 and 0.6 ± 0.1 mm, with pedicle lengths of 16.8 ± 5.1 and 21.2 ± 12.3 mm, respectively. At the two main clusters of perforator-intensive sites, the vessel chains formed by adjacent perforators are parallel to the intermuscular septum of the extensor carpi ulnaris and the extensor digitorum communis. CONCLUSIONS: This study demonstrates that the posterior interosseous artery has two main clusters of perforators in the middle and distal one-fifth of the forearm, which can be used for repairing hand defects with posterior interosseous artery chain-link perforator flaps.

Effects of indomethacin on human choroidal melanoma OCM-1 xenografts in nude mouse / 中华实验眼科杂志

Background Choroidal melanoma(CM)is a common form of primary ocular cancer in adults.It is reported that indomethacin has inhibitory effect on many tumor in vitro and in vivo,but whether it can inhibit the growth of CM has not been published. Objective This study was to investigate the anti-tumor activity of indomethacin on the growth of human CM OCM-1 cell xenografts in nude mice. Methods OCM-1 cells were subcutaneously implanted on 24 SPF female BALB/C.nu/nu nude mice to establish ectopic models of human CM.The nude mice with the tumor 5 mm were randomly divided into 4 groups:untreated group,normal saline solution(NS) group,indomethacin 1 ms/kg group,indomethacin 2 ms/kg group.The 1 mS/kg or 2 ms/kg indomethacin was intraperitoneally injected for 14 consecutive days in indomethacin 1 ms/kg group and indomethacin 2 me/kg group respectively.and 0.2 ml of 2%NS-DMSO was used at a same way in the NS group.No any agent was used as the untreated group.The volume and weight of implanted tumor as well as inhibitory rates of indomethaein on tumor were calculated.The expression of ki67 and survivin proteins were measured with immunohistochemistry,and the expression of survivin mRNA in CM was assessed by RT-PCR. ResuIts The tumor of indomethacin treatment group was reduced in volume and weight with a significant difference between treatment group and control group as well as indomethacin 1 ms/ks group and indomethacin 2 ms/kg group(P＜0.05).The inhibitory rate of indomethacin 1 ms/kg and 2 ms/kg for tumor was 22.86%,48.00%respectively.The prolifiration index (PI)of ki67 in these 4 groups were (76.73±3.34)%,(73.30±2.95)%,(55.97±2.24)%,(32.87±2.91)%respectively,and significant difference was found in PI between indomethacin 2 mg/kg group and untreated group or NS group(P＜0.05),but there was not significant difference between indomethacin 1 mg/kg and 2 ms/kg group(P＞0.05).Compared with the control group,the indomethacin treatment groups showed the decreased expression of survivin protein and mRNA,and significant difference was found between indomethaein 2 ms/kg group and untreated group or NS group(P＜0.05),however,no significant difference was found between indomethacin 1 mg/kg and 2 mg/kg group(P＞0.05). Conclusion Indomethacin inhibits the growth of CM in nude mice through inhibiting the expression of survivin in the tumor and accelerating cell apoptosis and inhibiting tumor cell proliferation.