Blood marker for assisting with diagnosis of nerve entrapment injury of limbs

Abstract

The use of an LRG1 quantitative reagent in the preparation of a diagnostic or auxiliary diagnostic reagent for nerve entrapment injuries of the limbs, and a diagnostic or auxiliary diagnostic system for nerve entrapment injuries of the limbs comprising an LRG1 quantitative device. With nerve entrapment caused by limb tumors, the average level of LRG1 in blood is elevated compared with that of normal people, and the elevation becomes more significant with aggravation of the injury, indicating that LRG1, as a peripheral blood marker for nerve entrapment caused by limb tumors, has a relatively high sensitivity and specificity.

Description

A blood marker to assist in the diagnosis of nerve entrapment injuries in the limbs Technical Field

[0001] This invention belongs to the field of biomedicine industry, specifically involving the application of LRG1 quantitative reagent in the preparation of reagents for detecting nerve entrapment injuries in the limbs. Background Technology

[0002] 1. Compression injuries of the limbs are commonly seen in carpal tunnel syndrome, cubital tunnel syndrome, supinator syndrome, pronator teres syndrome, piriformis syndrome, peroneal nerve entrapment syndrome, and tarsal tunnel syndrome, among which compression of the peripheral nerves of the upper limbs is more common.

[0003] 1.1 Carpal Tunnel Syndrome

[0004] The carpal tunnel is located at the base of the palm, formed by the carpal bones at its base and sides, with the transverse carpal ligament crossing it to form a bone-fibrous passage. Carpal tunnel syndrome (CTS), commonly known as mouse hand, is a peripheral nerve entrapment syndrome caused by compression of the median nerve within the carpal tunnel. The main symptoms are pain in the anterior wrist and numbness and weakness in the hand, commonly affecting the radial three and a half fingers innervated by the median nerve.

[0005] 1.2 Pronator teres syndrome

[0006] This condition occurs when the median nerve is compressed in the proximal forearm by the tendinous arch between the two heads of the pronator teres muscle. It is most common during repeated, forceful pronation of the forearm. The main symptom is proximal forearm pain, primarily in the pronator teres region, which may radiate to the elbow, upper arm, neck, and wrist. Other symptoms include numbness on the radial side of the palm and three and a half fingers on the radial side; weakened pinching strength of the thumb and index finger; hyperflexion of the metacarpophalangeal joint of the thumb and hyperextension of the proximal interphalangeal joint of the index finger when the thumb and index finger are opposed; and mild atrophy of the thenar muscles.

[0007] 1.3 Suppressor syndrome

[0008] Supinator syndrome is caused by compression of the deep branch of the radial nerve (dorsal interosseous nerve) near the supinator tendon arch. Clinical manifestations include forearm extensor dysfunction; thumb abduction and extension impairment; inability to actively extend the metacarpophalangeal joints of the 2nd to 5th fingers; and the wrist joint can be actively extended (the radial extensor carpi radialis is not innervated by the deep branch of the radial nerve). There is no sensory abnormality in the thenar eminence.

[0009] 1.4 Cubital tunnel syndrome

[0010] Two bony prominences can be palpated on the posteromedial aspect of the elbow joint (between the medial epicondyle of the humerus and the olecranon of the ulna). Between them lies a narrow, deep, arc-shaped bony groove containing a fibrous sheath—the ulnar groove. Within this groove, a cord-like structure, the ulnar nerve, can be felt. Around the elbow joint, the ulnar nerve runs within the cubital tunnel (cubital-ulnar tunnel). In a narrow sense, the cubital tunnel refers to the ulnar groove, while in a broader sense, it extends from the Struthers arch on the medial aspect of the upper arm (approximately 8 cm from the medial epicondyle) to the proximal forearm (between the ulnar and humeral heads of the flexor carpi ulnaris). Compression, traction, or friction of the ulnar nerve within this tunnel can produce a series of symptoms and signs. Common clinical manifestations include paresthesia or numbness in the ring and little fingers. In severe cases, weakness in the hand, muscle atrophy, decreased dexterity, and impaired fine motor skills may occur.

[0011] 1.5 Ulnar tube syndrome of the carpal tunnel

[0012] Ulnar tunnel syndrome, also known as Guyon's tunnel syndrome, lenticule-hook foramen syndrome, or Ramsay-Hunt syndrome, occurs in the wrist. The ulnar tunnel is triangular in cross-section, with the superficial transverse carpal ligament as its anterior wall, the deep transverse carpal ligament as its posterior wall, and the pisiform bone and lenticule-hook ligament as its medial wall. The ulnar nerve, ulnar artery, and vein pass through it. Compression of the ulnar nerve within the tunnel causes ulnar tunnel syndrome. Involvement of the superficial branches causes sensory disturbances in the area innervated by the ulnar nerve. Compression of the deep branches can lead to atrophy and weakness of the intrinsic muscles of the hand, deep swelling and burning pain in the hand, significant nocturnal pain, thumb adduction, weakness in the adduction and abduction of the other four fingers, and claw deformity of the ring and little fingers. The paper-pinching test and Froment test are positive.

[0013] 1.6 Peroneal nerve entrapment syndrome

[0014] This condition is caused by compression of the common peroneal nerve within the osteofascial canal at the fibular neck. Injury and external compression are common causes. Symptoms include pain, numbness, and motor dysfunction in the foot and lateral lower leg. There may be weakness in ankle dorsiflexion and toe extension, and weak or absent eversion. Sensory disturbances may be present on the lateral lower leg and foot, and tenderness and Tinel's sign may be present at the fibular neck.

[0015] 1.7 Tarsal tunnel syndrome

[0016] Also known as plantar tunnel syndrome, it refers to a series of clinical symptoms and signs caused by compression of the tibial nerve as it travels through the tarsal tunnel located below and behind the medial malleolus to the sole of the foot. The onset is slow and usually unilateral. In the early stages, symptoms include intermittent pain, tightness, swelling, discomfort, or numbness in the sole and heel. The pain sometimes radiates to the calf and sometimes involves twitching along the arch of the foot. Symptoms worsen after prolonged standing or walking, and there is a history of nocturnal awakening due to pain. Most patients experience relief after removing their shoes.

[0017] 2. Mechanism of peripheral nerve entrapment injury: The underlying mechanism of nerve entrapment injury

[0018] The peripheral nervous system connects to the brain or spinal cord of the central nervous system at one end and to various organs and systems of the body at the other. Nerves are composed of nerve fibers, which are made up of long processes of neurons and a portion of glial cells surrounding them. The processes of Schwann cells, which are glial cells, surround the neuronal axon to form a myelin sheath with concentric lamellar structures. The myelin sheath provides insulation and support, ensuring high-speed conduction of electrical signals by the axon. Based on whether or not they have a myelin sheath, nerve fibers can be divided into myelinated fibers and unmyelinated fibers.

[0019] In addition to the nerve membrane and myelin sheath composed of Schwann cells, nerve fibers are surrounded by connective tissue to form the endoneurium, which contains fibrous matrix and fibroblasts. Many nerve fibers bundle together and are surrounded by a relatively dense layer of connective tissue called the perineurium. The perineurium generally contains 15-20 layers of cells and is a metabolically active diffusion barrier.

[0020] Nerves are composed of bundles of nerves of varying thicknesses, which are surrounded by a layer of loose connective tissue called the epineurium. The epineurium contains collagen fibers, fibroblasts, fat, lymphatic vessels, blood vessels, and nerves (i.e., nerves within nerves).

[0021] Blood vessels of nerves: Blood vessels of nerves are divided into external and internal systems.

[0022] External system: namely local nutrient vessels and epineurial vessels, which originate from the accompanying vessels of adjacent tissues. They branch off segmental vessels at certain intervals to the epineurium and then divide into ascending and descending branches. The ascending and descending branches of adjacent segmental vessels anastomose with each other to form longitudinally arranged epineurial vessels.

[0023] Short transverse or oblique branches of the epineurium extend through the epineurium to the interfascicles, forming interfascicular vessels. Branches of these interfascicular vessels then pass through the perineurium into the fascicles, forming intrafascicular microvessels that eventually reach the endoneurium, thus completing the blood supply to the nerve fibers.

[0024] The intrinsic system refers to the longitudinal network of microvessels within the endothelial nerve membrane. The two vascular systems have abundant anastomoses. The smooth muscle of the blood vessels in the intrinsic system is poorly developed and lacks self-regulation, while the extrinsic system has nerve plexuses in its vessel walls, providing some regulatory function.

[0025] The connective tissue (ependymium) of peripheral nerves contains nerve tissue. These nerve sheaths are also called nerve sheaths. The nerve function ensures intrinsic nerve sensitivity, allowing it to regulate external mechanical stimuli (such as nerve entrapment) and its own metabolic nutrition. Additionally, the vascular sheath of nerves also has innervation, which can be used to regulate vasoconstriction and vasodilation.

[0026] Mechanical properties of nerves

[0027] Agency: refers to the various forces exerted on the nerve tissue by the body's activities. Nerves have the characteristic of adapting to external forces, such as sliding within the path (channel) they pass through; changing their shape (folds, twists, folds, etc.) to mitigate external damage and withstand a certain degree of traction.

[0028] Viscoelasticity: When an object with viscoelastic properties is subjected to an external force, it immediately adapts to the deformation by means of deformation; however, after the external force is removed, it retains some of the deformation. Objects with elastic properties are different; these objects immediately return to their original shape after the external force is removed.

[0029] Nerve tissue is a viscoelastic structure. When nerves are subjected to traction forces, the viscoelasticity provides them with greater resilience, preventing them from rupturing even when excessively stretched. However, when subjected to compressive forces, nerves are easily damaged, regardless of the magnitude of the force.

[0030] The intrinsic tension environment of nerve tissue

[0031] Endogenous neuronal pressure represents the sum of all intracellular (axonal hydraulic pressure); this hydraulic pressure is further increased by the blood pressure in the nerve-nourishing blood vessels; viscoelasticity makes nerve tissue easily exposed to longitudinal, eccentric, and distal tension; as soon as the tension intensity changes, the endogenous neuronal pressure changes immediately. Exogenous neuronal pressure acts on the various sheaths covering the nerve.

[0032] The relative relationship between tension and pressure: Directly compressing nerve tissue will cause a sharp increase in the tension within the tissue; applying longitudinal tension to an already taut nerve tissue will reduce it.

[0033] Peripheral nerve injuries include intrinsic nerve injuries: fibrosis, hematoma, intrinsic pressure on nerve tissue, primary local ischemia, and obstruction of lymphatic and venous return. Extrinsic nerve injuries occur when nerves pass through osteofibrous canals, penetrate or emerge from the deep fascia, or pass through muscles, making them prone to entrapment. Examples of common entrapment sites include the median nerve in the carpal tunnel, the median nerve beneath the pronator teres muscle, the musculocutaneous nerve passing through the coracobrachialis muscle, and the superficial peroneal nerve emerging from the deep fascia in the middle to distal third of the lower leg. Extrinsic nerve entrapment can be classified as acute or chronic based on its nature.

[0034] Acute nerve entrapment can cause blockage of blood vessels within the nerve, affecting nerve function and mechanically damaging nerve structure. Chronic nerve entrapment leads to thickening of the epineurium, demyelination of myelinated nerves, and even nerve fiber degeneration (also known as secondary degeneration, which refers to a series of degenerative processes and cellular phagocytosis occurring distal to nerve axonal injury due to blocked axoplasmic transport). Furthermore, after nerve entrapment, motor nerve conduction velocity initially increases, but slows down as the disease progresses.

[0035] Multiple nerve entrapment syndrome refers to a nerve being entrapped in multiple places along its course. Each entrapment may not produce any symptoms on its own, but the combination of these entrapments can manifest as symptoms of nerve entrapment.

[0036] In 1973, Upton and McComas clinically observed evidence of cervical radiculopathy in carpal tunnel syndrome and ulnar neuropathy. They pointed out that the predisposition of carpal tunnel syndrome in diabetes is due to multiple nerve compressions: individual compressions may not produce any symptoms, but the combined effect can. For example, the transverse carpal ligament may compress the median nerve without causing symptoms, but with age, the development of cervical spondylosis or thoracic outlet syndrome will lead to typical carpal tunnel syndrome symptoms. Therefore, it is essential to understand the locations and pinpoints of nerve compression along its course.

[0037] 3. Effects of nerve injury

[0038] When a single or multiple kink syndrome occurs in the peripheral nerve during its course, mild nerve damage symptoms often appear. If the nerve damage is mild and the nerve is irritated, the muscles it innervates will show increased tension, or increased tension in some muscle fibers (cords can be palpated within the muscle). Muscle strength may increase in the early stages and decrease in the later stages.

[0039] Sensitivity, decreased sensation, or pain may occur in the skin of the nerve innervation area. Furthermore, impaired proprioceptive afferent stimulation after nerve damage can lead to joint or bodily instability. The motor sensory system maintains joint and bodily balance; damage to sensory nerve fibers can reduce, increase, or cause abnormalities in the information transmitted to the central nervous system, resulting in efferent abnormalities manifesting as joint or bodily instability. Conversely, damage to motor nerve fibers can cause efferent abnormalities even if the input signals are normal, resulting in joint or bodily instability.

[0040] 4. Clinical Manifestations

[0041] Depending on the location and structure of the nerve entrapment, the symptoms vary. Common symptoms include:

[0042] Pain often manifests as numbness and pain in the area innervated by the nerve, typically most severe at night or in the early morning, and may radiate. The pain can be relieved by appropriate activity. For example, carpal tunnel syndrome often begins with numbness, pain, and weakness in the tips of the thumb, index, and middle fingers, which can be relieved by gently shaking the wrist.

[0043] Sensory disturbances, including loss or abnormality of sensation in the nerve-innervated area.

[0044] Deformities: Partial nerve entrapment can cause hand deformities. For example, patients with cubital tunnel syndrome may experience atrophy of the hypothenar and interosseous muscles, and claw-like deformities of the ring and little fingers. Patients with supinator syndrome can actively extend their wrists, but the wrists deviate to the affected side, and there is dysfunction of the forearm extensor muscles.

[0045] Motor dysfunction: Impaired neuromotor function manifests as difficulty holding objects, limping, etc. For example, patients with supinator syndrome have difficulty abducting and extending the thumb, and cannot actively extend the metacarpophalangeal joints. Patients with piriformis syndrome may have painful limping and mild calf muscle atrophy.

[0046] 5. Diagnosis of peripheral nerve entrapment:

[0047] This typically involves taking a medical history, performing a physical examination, and conducting necessary imaging and electrophysiological tests to confirm the location and severity of nerve compression.

[0048] Medical history taking: The doctor will ask the patient in detail about their symptoms, duration, and triggering factors. Common symptoms include pain, numbness, tingling, or weakness, which may worsen or improve with activity.

[0049] Physical examination: Through palpation, observation of movement, and specific postural tests, doctors can assess neurological function. For example, Tinel's sign or Phalen's test can be used to detect carpal tunnel syndrome.

[0050] Imaging studies: Imaging techniques such as X-rays, ultrasound, CT, or MRI can help identify structural problems that cause nerve compression, such as skeletal deformities, tumors, or cysts.

[0051] Electrophysiological examinations: Electromyography and nerve conduction velocity tests can measure the electrical activity of nerves and muscles, and assess the extent and location of nerve damage. These tests are crucial for determining the specific nature of nerve damage.

[0052] By following the steps above, the cause and location of nerve entrapment can be determined more accurately, providing guidance for subsequent treatment. Early identification and intervention help improve symptoms and prevent long-term damage.

[0053] 6. Prevention and Treatment

[0054] Tumors compressing nerves can generally be resolved through physical therapy, medication, or surgery.

[0055] Physical therapy: If the tumor is benign and large enough to compress nerves, it can be improved through physical therapy such as massage, acupuncture, etc.

[0056] Drug treatment: If the nerves compressed by the tumor cause pain, you can take pain-relieving and nerve-nourishing drugs such as ibuprofen tablets and vitamin B complex tablets under the guidance of a doctor.

[0057] Surgical treatment: If the tumor is large and continues to compress the nerves, it may have a certain impact on the body's health. Therefore, it is necessary to treat the tumor by surgical removal in a timely manner.

[0058] 7. Relationship with proteins in the blood:

[0059] Proteins are the functional executors of genes. Research into protein structure, location, and protein-protein interactions provides a direct foundation for elucidating the nature of life phenomena. Almost all physiological and pathological processes, as well as the effects of drugs and environmental factors, depend on proteins and cause changes in the proteome. Before any disease manifests any perceptible symptoms, certain proteins have certainly undergone changes. Therefore, identifying key and marker proteins for various diseases is of great significance for disease diagnosis, pathological research, and drug screening.

[0060] Leucine-rich repeat (LRR) proteins are a family of proteins consisting of eight leucine-rich repeat sequences. Studies have shown that LRR proteins are transmembrane proteins that mainly participate in normal physiological activities as cell adhesion molecules or ligand-binding proteins.

[0061] Leucine-rich α2-glycoprotein 1 (LRG1) is a member of the leucine-rich repeat family and belongs to the LRR protein family. Previous studies have shown that LRG1 participates in important physiological and pathological processes, such as protein-protein interactions, signal transduction, and cell adhesion.

[0062] Currently, various proteins with leucine-rich repeat structures have been found in the nervous system. In some neurodegenerative diseases, decreased concentrations of LRG1 in cerebrospinal fluid (CSF) have been detected, and human LRG1 expression has been observed in the anatomically examined cerebral cortex. Previous studies have performed proteomic analysis on CSF samples from healthy individuals and patients with idiopathic normal pressure hydrocephalus (INPH), finding a specific increase in LRG1 expression in the CSF of INPH patients. Therefore, LRG1 has potential value in the clinical diagnosis of INPH. Abnormal LRG1 expression is associated with the development of various tumors, such as glioma, lung cancer, colon cancer, epithelial ovarian cancer, and hepatocellular carcinoma.

[0063] In studies of retinopathy caused by vascular remodeling, LRG1 was found to promote endothelial cell mitosis and angiogenesis. This hypothesis was further confirmed in in vitro human vascular endothelial cell (HUVEC) lumen formation assays. Providing recombinant human LRG1 as a medium resulted in a significant increase in lumen formation and branching, while anti-LRG1 antibodies significantly blocked lumen formation. Other studies have shown that the angiogenic activity of LRG1 is not limited to the eye and may play important roles in other major biological processes, including tumors and immune responses. The regulatory role of LRG1 on the TGF-β1 signaling pathway provides strong evidence for the function of LRG1. LRG1 is a very promising therapeutic target for controlling ocular angiogenesis and may play an important role in other diseases such as cancer and atherosclerosis.

[0064] The function of LRG1 may be related to its LRR structure. LRG is thought to regulate the function of other proteins, such as cytochrome C, by binding to them, thereby limiting the function of some proteins. Gliomas originate from glial cells and are the most common tumors of the central nervous system, accounting for 30% of all brain and central nervous system tumors and 80% of all malignant brain tumors. Related experiments have shown that LRG1 plays an important role in promoting the proliferation, migration, and invasion of glioma cells, and these functions are achieved by mediating the transforming growth factor β1 (TGF-β1) signaling pathway. Furthermore, LRG1 can promote endothelial cell proliferation and angiogenesis through the TGF-β signaling pathway, suggesting that LRG1 may be involved in the occurrence and development of astrocytic malignancies. Previous studies have shown that inhibiting LRG1 expression inhibits the in vitro growth of glioma cells and delays the occurrence of gliomas in xenograft mouse models, providing evidence for the tropism of LRG1 on glioma pathological changes. LRG1 is associated with atherosclerosis and microcirculatory disturbances, and may serve as a biomarker of vascular injury in different vascular beds. LRG1 has the potential role in the early identification of vascular disease risk, but the pathological basis and mechanisms underlying these associations require further investigation. Altering LRG1 activity could be considered as a therapeutic potential in vascular diseases, particularly in minimally invasive surgery and endovascular revascularization. LRG1 expression is upregulated after myocardial infarction, and inhibiting post-infarction cardiac remodeling is a novel cardiovascular protective factor; therefore, LRG1 may become a therapeutic target for cardiovascular diseases. LRG1 gene deletion exacerbates post-infarction cardiac dysfunction and increases myocardial fibrosis. In LRG1-deficient mice, impaired smad1 / 5 / 8 pathways lead to reduced capillary density at the infarct margin, and LRG1 gene ablation further exacerbates the reduction in capillary density after myocardial infarction in cardiac remodeling models. Furthermore, our study indicates that elevated LRG1 levels in the blood of patients with cardiac and respiratory arrest following cardiopulmonary resuscitation may be associated with cerebral ischemia, brain injury, and vascular damage caused by cardiac and respiratory arrest. This is consistent with the mechanism of elevated LRG1 levels in the blood of patients with cerebral infarction and myocardial infarction.

[0065] On the other hand, LRG1, as an angiogenesis factor, may have considerable potential for the treatment of vascular diseases by regulating the smad1 / 5 / 8 pathway, but its specific regulatory mechanism is still unclear.

[0066] The inventor's prior Chinese patent application CN117110626A discloses that the average value of LRG1 in the blood is higher in individuals with carotid artery disease than in normal individuals, and that the detachment of plaques from carotid vessels increases more significantly as the disease progresses. As a peripheral blood biomarker for dangerous carotid artery disease, it exhibits high sensitivity and specificity and can be used in conjunction with ultrasound results for the diagnosis of carotid artery disease. CN115856325A discloses that the level of peripheral blood LRG1 is closely related to lower limb arterial injury. By detecting the level of LRG1 in peripheral blood, lower limb arterial injury, especially lower limb arteriosclerosis or plaque, lower limb arterial stenosis, thrombosis, or occlusion, can be well predicted. In particular, it can effectively predict lower limb arteriosclerosis or plaque, lower limb arterial stenosis, thrombosis, or occlusion caused by hypertension, hyperlipidemia, or hyperglycemia. CN110261617A discloses that LRG1 can be used as a peripheral blood biomarker for cerebral hemorrhage. Technical issues

[0067] In the current technology, no research has shown that LRG1 is associated with nerve entrapment injury in the limbs. Solution

[0068] The purpose of this invention is to overcome at least one deficiency of the prior art and to provide the application of LRG1 quantitative reagent in the preparation of reagents for detecting nerve entrapment injuries of the limbs.

[0069] The technical solution adopted in this invention is:

[0070] The first aspect of the present invention provides:

[0071] Application of LRG1 quantitative reagent in the preparation of diagnostic or auxiliary diagnostic reagents for nerve entrapment injuries of the limbs.

[0072] In some instances, the LRG1 quantification reagent is an ELISA reagent, an immunofluorescence reagent, or a mass spectrometry analysis reagent.

[0073] In some instances, the samples tested by the LRG1 quantitative reagent are peripheral blood.

[0074] In some instances, the limb nerve entrapment injury is a limb nerve entrapment injury caused by a tumor.

[0075] A second aspect of the present invention provides:

[0076] A diagnostic or auxiliary diagnostic system for nerve entrapment injuries of the limbs, comprising:

[0077] The LRG1 quantification device is used to quantify the amount of LRG1 in a sample.

[0078] The analytical device, based on the LRG1 content, determines the risk of nerve entrapment injury in the limbs;

[0079] The result output device is used to output the analysis results of the analysis device.

[0080] In some instances, the LRG1 quantification device is an ELISA detection device, an immunoblotting device, an immunofluorescence device, or a mass spectrometry device.

[0081] In some cases, high levels of LRG1 indicate a high risk of nerve entrapment injury in the limbs.

[0082] In some cases, high LRG1 levels refer to levels exceeding 5 ng / mL in peripheral blood samples.

[0083] In some instances, the sample is peripheral blood.

[0084] In some instances, the limb nerve entrapment injury is a limb nerve entrapment injury caused by a tumor. Beneficial effects

[0085] The inventors' first study confirmed that LRG1 is a peripheral blood marker for nerve entrapment injury in the limbs. The average value of LRG1 in the blood during nerve entrapment injury is higher than that in normal people, and the increase is more significant as the injury worsens. As a peripheral blood marker for nerve entrapment caused by limb tumors, it has high sensitivity and specificity.

[0086] The experimental results showed that, using a peripheral blood LRG1 level of 5 ng / ml as the cutoff value, 28 out of 30 patients with limb nerve entrapment injuries were successfully detected, with 2 false negatives, resulting in a sensitivity of 93.33%. In 60 normal individuals, 12 false positives were observed, with a specificity of 80%. Postoperative LRG1 levels in patients with limb nerve entrapment injuries were significantly lower than preoperative levels (P<0.001), and comparable to normal levels (P>0.05). Embodiments of the present invention

[0087] The first aspect of the present invention provides:

[0088] Application of LRG1 quantitative reagent in the preparation of diagnostic or auxiliary diagnostic reagents for nerve entrapment injuries of the limbs.

[0089] LRG1 quantification reagents can be any conventional protein quantification reagents, with no special requirements. In some examples, the LRG1 quantification reagent is an ELISA reagent, an immunofluorescence reagent, or a mass spectrometry analysis reagent. ELISA reagents are preferred for LRG1 quantification because they are easy to use and the results meet the requirements.

[0090] In some instances, peripheral blood is used as the sample for LRG1 quantification. Peripheral blood is readily available and widely accepted.

[0091] In some instances, the nerve entrapment injury of the limbs is caused by a tumor, particularly a benign tumor.

[0092] A second aspect of the present invention provides:

[0093] A diagnostic or auxiliary diagnostic system for nerve entrapment injuries of the limbs, comprising:

[0094] The LRG1 quantification device is used to quantify the amount of LRG1 in a sample.

[0095] The analytical device, based on the LRG1 content, determines the risk of nerve entrapment injury in the limbs;

[0096] The result output device is used to output the analysis results of the analysis device.

[0097] There are no special requirements for the type of LRG1 quantification device, as long as it can effectively quantify the amount of LRG1. In some examples, the LRG1 quantification device is an ELISA detection device, an immunoblotting device, an immunofluorescence device, or a mass spectrometry device.

[0098] In some cases, high levels of LRG1 indicate a high risk of nerve entrapment injury in the limbs.

[0099] In some cases, high LRG1 levels refer to levels exceeding 5 ng / mL in peripheral blood samples.

[0100] In some instances, the sample is peripheral blood.

[0101] In some instances, the nerve entrapment injury of the limbs is caused by a tumor, particularly a benign tumor.

[0102] Screening and collection of clinical samples:

[0103] Thirty cases of benign limb tumors causing nerve entrapment injury and 30 cases of other benign upper limb tumors without nerve entrapment injury were collected within the past 5 years. Gender and age were recorded. All patients underwent blood pressure, blood lipids, blood glucose, liver function, kidney function, coagulation parameters, and ECG. All cases were confirmed by ultrasound, CT, and neurophysiological examination. Sixty age- and sex-matched healthy individuals were selected as controls. Specimen collection: 5 mL of venous blood was collected from patients meeting the inclusion criteria, allowed to stand for 15 min, centrifuged at 3000 rpm for 15 min, and the serum was extracted, placed in sterile cryovials, and stored at -80℃ for research. Blood samples were collected again after surgery for patients with nerve entrapment injury.

[0104] Study of blood samples from case patients

[0105] Serum separation. The examination method is as follows: serum and cells are separated using a high-speed centrifuge.

[0106] Main equipment, materials, and reagents: homogenizer, high-speed centrifuge, 3kDa ultrafiltration centrifuge tubes, ICP-MS. The water used in the experiment was ultrapure water with a concentration of 18.2 MΩ / cm. Sample pretreatment methods: 1) Fully automated biochemical analyzer (one each of Bekmann DXC800 and AU400), 0.01% electronic analytical balance (Shimadzu), microplate reader, Roche electrochemiluminescence automated immunoassay analyzer (Elecsys 2010), specific protein analyzer (imported), purified water system (MEDICA60), electric thermostatic water bath (DK-600), low-temperature high-speed centrifuge (Sigma), ultra-low temperature freezer (Thermo Fisher Scientific), low-temperature freezer (HFC350, Germany), etc. The above equipment conditions fully guarantee the implementation of this project.

[0107] Statistical methods:

[0108] The t-test was used to compare the means of each group. SPSS statistical software was used, and P < 0.05 was considered statistically significant.

[0109] result:

[0110] The normal range is determined by adding two standard deviations to the mean. For the LRG1 detection kit produced in Huizhou (LRG1 Huizhou), the upper limit of normal is 5 ng / ml. In a study of 30 cases of benign limb tumors without nerve entrapment and 30 cases of benign limb tumors with nerve entrapment, the cutoff value was 5 ng / ml. 28 results exceeded the cutoff value, resulting in 2 false negatives, with a sensitivity of 93%. In a study of 60 normal individuals, 12 results exceeded the cutoff value, resulting in a false positive rate of 20% and a specificity of 80%.

[0111] The changes in peripheral blood LRG1 in limb nerve entrapment injuries are shown in Table 1.

[0112] Table 1: Peripheral blood LRG1 changes (X±SD, unit ng / ml) in benign tumors of the extremities with nerve entrapment injury

[0113] Number of people, LRG1 (Huizhou) / ng / ml, normal individuals: 603.2±1.1, limb tumors without nerve entrapment injury: 303.6±1.0, limb tumors with nerve entrapment injury: 3012.6±2.1

[0114] The incidence of nerve entrapment injury in the limbs was significantly higher than that in normal individuals and those without entrapment (P<0.001). There was no difference between individuals with simple benign tumors without nerve entrapment injury and normal individuals.

[0115] Sensitivity and specificity of LRG1 in diagnosing nerve entrapment injuries in the limbs

[0116] Sensitivity = (Number of true positives / (Number of true positives + Number of false negatives)) * 100%, the percentage of patients correctly diagnosed.

[0117] Specificity = (Number of true negatives / (Number of true negatives + Number of false positives)) * 100%, the percentage of individuals correctly identified as not being patients.

[0118] False positive rate = Number of false positives / Number of negative results (gold standard)

[0119] False negative rate = Number of false negatives / Number of gold standard positives

[0120] The normal upper limit of the LRG1 detection kit produced in Huizhou is 5 ng / ml. When the kit was used to detect 30 cases of limb tumors with nerve entrapment injury, the cutoff value was 5 ng / ml. 28 cases exceeded the cutoff value, and there were 2 false negatives, with a sensitivity of 93.33%. Among 60 normal individuals, 12 exceeded the cutoff value, and there were 20 false positives.

[0121] Table 2 shows the changes in LRG1 before and after treatment for nerve entrapment injuries of the limbs.

[0122] Table 2: Changes in LRG1 levels before and after treatment for nerve entrapment injuries of the limbs

[0123] Case count: LRG1 / ng / ml: Normal individuals: 603.2±1.1; Limb tumors with nerve entrapment injury: Preoperative: 3012.6±2.1; Limb tumors with nerve entrapment injury: Postoperative: 193.2±2.3

[0124] After surgery for nerve entrapment injury of the limbs, LRG1 was significantly reduced compared with that before surgery (P<0.001), which was comparable to the level of normal individuals (P>0.05).

[0125] The above experimental results show that the average value of LRG1 in the blood is higher than that in normal people when nerve entrapment is caused by tumors in the limbs, and the increase is more significant as the injury worsens. As a peripheral blood marker for nerve entrapment caused by tumors in the limbs, it has high sensitivity and specificity.

[0126] This invention is the first to propose and verify that LRG1 is a peripheral blood marker for nerve entrapment caused by tumors in the limbs, and the results can be used to diagnose nerve entrapment caused by tumors in the limbs.

[0127] The above is a further detailed description of the present invention and should not be considered as a limitation on the specific implementation of the present invention. For those skilled in the art, simple deductions or substitutions without departing from the concept of the present invention are all within the protection scope of the present invention.

[0128] References:

[0129] [1] Tessa Gordon 1, Nasim Amirjani, David C Edwards, K Ming Chan,Brief post-surgical electrical stimulation accelerates axon regeneration and muscle reinnervation without affecting the functional measures in carpal tunnel syndrome patients. Trial Exp Neurol. 2010 May;223(1):192-202.

[0130] [2] Proteomic analysis of hippocampus in mice following long-term exposure to low levels of copper. Qian Sun, Ming Ying, Quan Ma, Zhijun Huang, Liangyu Zou, Jianjun Liu, Zhixiong Zhuang, Xifei Yang. Toxicol. Res.,2016,4,28

[0131] [3] Serum proteomic analysis reveals potential serum biomarkers for occupational medicamentosa-like dermatitis caused by trichloroethylene Peiwu Huang a,d,1, Xiaohu Ren a,1, Zhijun Huang c,1, Xifei Yang a, Wenxu Hong a, Yanfang Zhang b, Hang Zhang a,d, Wei Liu a, Haiyan Huang a, Xinfeng Huang a, Desheng Wua, Linqing Yang a, Haiyan Tang b, Li Zhou a, Xuan Li a, Jianjun Liu。Toxicology Letters 2014,6,21(sci 3.75)

[0132] [4] 1. Ditochondrial proteomic alterations caused by long-term low –dose copper exposure in mouse cortex. Xuemei Lin, Gang Wei, Zhijun Huang, etc. Toxicology Letter, 2016

[0133] [5]. Detection of coagulation factor VIIR353Q genotype in Han Chinese patients with cerebral hemorrhage in South China. Chinese Journal of Arteriosclerosis, 2007, 6.

[0134] [6]. Research progress on the application of gene chips in the diagnosis and treatment of cardiovascular diseases, 2005, 10, *Chinese Journal of Medical Engineering*.

[0135] [7] Application of factor DNA molecular genetic markers RFLP, STR, and SNP in coagulation genotype analysis. Chinese Journal of Misdiagnosis Medicine, 2006, 4.

Claims

1. Application of LRG1 quantitative reagent in the preparation of diagnostic or auxiliary diagnostic reagents for nerve entrapment injuries of the limbs.

2. The application according to claim 1, characterized in that, The LRG1 quantitative reagents are ELISA reagents, immunofluorescence reagents, and mass spectrometry analysis reagents.

3. The application according to claim 1, characterized in that, The sample tested by the LRG1 quantitative reagent is peripheral blood.

4. The application according to claim 1, characterized in that, The nerve entrapment injury in the limbs was caused by a tumor.

5. A diagnostic or auxiliary diagnostic system for nerve entrapment injuries of the limbs, comprising: The LRG1 quantification device is used to quantify the amount of LRG1 in a sample. The analytical device, based on the LRG1 content, determines the risk of nerve entrapment injury in the limbs; The result output device is used to output the analysis results of the analysis device.

6. The limb nerve entrapment injury diagnostic system according to claim 5, characterized in that, The LRG1 quantification device is an ELISA detection device, an immunoblotting device, an immunofluorescence device, or a mass spectrometry device.

7. The limb nerve entrapment injury diagnostic system according to claim 5, characterized in that, High levels of LRG1 indicate a high risk of nerve entrapment injury in the limbs.

8. The limb nerve entrapment injury diagnostic system according to claim 7, characterized in that, High LRG1 content refers to its content in peripheral blood samples exceeding 5 ng / mL.

9. The limb nerve entrapment injury diagnostic system according to claim 5, characterized in that, The sample was peripheral blood.

10. The limb nerve entrapment injury diagnostic system according to claim 5, characterized in that, The nerve entrapment injury in the limbs was caused by a tumor.