The Effects of Recombinant Human Granulocyte-Macrophage Colony-Stimulating Factor Gel on Third-Degree Frostbite Wounds in Northeastern China: A Randomized Controlled Trial

The aim of the study was to investigate the effects of the rhGM-CSF gel on third-degree frostbite wounds. Sixty-two patients who had suffered third-degree frostbite on their hand or foot (91 wounds in total) were selected using a convenience sampling method and randomly allocated to two groups: the rhGM-CSF group(31patients,45 frostbite wounds) received the rhGM-CSF gel when wound dressing change daily; however, the control group (31patients, 46 frostbite wounds) received aloe glue. The wound healing time, the score of inflammation about the wound and the positive bacterial culture of wound secretions were used to measure outcomes, respectively. Data were analyzed using SPSS (25.0), Student's t test or Mann-Whitney U test and chi-square test or Fisher exact test were selected, as appropriate. The healing time of the rhGM-CSF group was (12.2 ± 5.0) days, which was significantly shorter than that of the control group (15.5 ± 4.7) days (P < .0001). The rhGM-CSF group's wound inflammation scores on the 7th and 14th day of treatment were (0.96 ± 0.21) and (1.88 ± 0.29), respectively, which were better than those of the control group (1.12 ± 0.24) and (1.38 ± 0.15) (both P < .0001). The positive bacterial culture of wound secretions in the rhGM-CSF group was also better than that in the control group on the 3rd, 7th, and 14th day after treatment (P = .027, .004, .030, respectively). According to the results, using rhGM-CSF gel considerably increases the speed of frostbite wounds healing, and have an effect on protecting third-degree frostbite wounds regarding the positive effects. Trial Registration: This trial was registered in the Chinese Clinical Trial Register, ChiCTR1900021299.

[Clinicopathological features and prognosis of anorectal melanoma: A report of 68 cases]

OBJECTIVE

To investigate the clinicopathological characteristics of anorectal mucosal melanoma (ARMM), and to evaluate the prognostic factors.

METHODS

A total of 68 primary ARMM surgical specimens from 2010 to 2018 were retrospectively studied. Slides were reviewed to evaluate pathological features. Slingluff staging method was used for staging.

RESULTS

(1) Clinical features: The median age at diagnosis in this group was 61.5 years, with a male-to-female ratio 1 ∶1.62. The most common complaint was blooding (49 cases). For anatomic site, anorectum was the prevalent (66.2%), followed by rectum (20.6%). At the time of diagnosis, 28 cases were stage Ⅰ (localized stage, 41.2%), 25 cases were stage Ⅱ (regional lymph node metastasis, 36.8%), and 15 cases were stage Ⅲ (distant metastasis, 22.1%). Five patients underwent wide local excision, the rest abdominoperineal resection, and 48 patients received adjuvant therapy after surgery. (2) Pathological features: Grossly 88.2% of the tumors were exophytic polypoid masses, with the median tumor size 3.5 cm and the median tumor thickness 1.25 cm. Depth of invasion below lamina muscularis mucosae ranged from 0-5.00 cm (median 1.00 cm). The deepest site of tumor invasion reached muscular layer in 27 cases, and perirectal tissue in 16 cases. Melanin pigmentation was absent or not obvious in 67.6% of the cases. The predominant cytology was epithelioid (45 cases, 66.2%). The rate for ulceration, necrosis, lymphovascular invasion, and perineural invasion was 89.7%, 35.3%, 55.9%, and 30.9%, respectively. The median mitotic count was 18/mm². The positive rate of S100, HMB-45 and Melan-A were 92.0%, 92.6% and 98.0%, respectively. The median of Ki-67 was 50%. The incidences of mutations within CKIT, BRAF and NRAS genes were 17.0% (9 cases), 3.8% (2 cases) and 9.4% (5 cases), respectively. (3) Prognosis: Survival data were available in 66 patients, with a median follow-up of 17 months and a median survival time of 17.4 months. The 1-year, 2-year and 5-year overall survival rate was 76.8%, 36.8% and 17.2%, respectively. The rate of lymphatic metastasis at diagnosis was 56.3%. Forty-nine patients (84.5%) suffered from distant metastasis, and the most frequent metastatic site was liver. Univariate analysis revealed that tumor size (>3.5 cm), depth of invasion below lamina muscularis mucosae (>1.0 cm), necrosis, lymphovascular invasion, BRAF gene mutation, lack of adjuvant therapy after surgery, deep site of tumor invasion, and high stage at diagnosis were all poor prognostic factors for overall survival. Multivariate model showed that lymphovascular invasion and BRAF gene mutation were independent risk factors for lower overall survival, and high stage at diagnosis showed borderline negative correlation with overall survival.

CONCLUSION

The overall prognosis of ARMM is poor, and lymphovascular invasion and BRAF gene mutation are independent factors of poor prognosis. Slingluff staging suggests prognosis effectively, and detailed assessment of pathological features, clear staging and genetic testing should be carried out when possible. Depth of invasion below lamina muscularis mucosae of the tumor might be a better prognostic indicator than tumor thickness.

Toripalimab (anti-PD-1) versus High-Dose Interferon-α2b as Adjuvant Therapy in Resected Mucosal Melanoma: A Phase II Randomized Trial

BACKGROUND

No standard of care for mucosal melanoma (MM) in the adjuvant setting has been established. Meanwhile, relapse-free survival (RFS) is only about five months after surgery alone. This phase II trial aimed to compare toripalimab vs. high-dose interferon-α2b (HDI) as an adjuvant therapy for resected MM.

PATIENTS AND METHODS

From July 2017 to May 2019, 145 patients with resected MM were randomized (1:1) to receive HDI (N = 72) or toripalimab (N = 73) for one year until disease relapse/distant metastasis, unacceptable toxicity, or withdrawal of consent. The primary endpoint was RFS. The secondary endpoints included distant metastasis-free survival (DMFS), overall survival (OS), and safety.

RESULTS

After a median follow-up of 26.3 months, the numbers of RFS, OS, and DMFS events were 51 vs. 46, 33 vs. 29, and 49 vs. 44 in the toripalimab arm and the HDI arm, respectively. The median RFS were 13.6 (95%CI: 8.31-19.02) months and 13.9 (95%CI: 8.28-19.61) months in the toripalimab arm and HDI arm, respectively. The DMFS was not significantly different between the two arms (HR: 1.00, 95%CI: 0.65-1.54). The median OS was 35.1 months (95%CI: 27.93-NR) in the toripalimab arm, with no significant difference in all-cause death (HR: 1.11, 95% CI: 0.66-1.84) for the two arms. The median sums of the patients' actual infusion doses were 3672 mg and 1054.5 MIU in the toripalimab arm and HDI arm, respectively. The incidence of treatment-emergent adverse events with a grade ≥ 3 was much higher in the HDI arm than in the toripalimab arm (87.5% vs. 27.4%).

CONCLUSION

Toripalimab showed a similar RFS and a more favorable safety profile than HDI, both better than historical data, suggesting that toripalimab might be the better treatment option. However, additional translational studies and better treatment regimens are still warranted to improve the clinical outcome of MM.

A specially designed medical screen for children suffering from burns: A randomized trial of a distraction-type therapy

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The current study is the first to explore the medical screen as a treatment to control the pain and its related psychological symptoms on children suffering from burns;.

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Compared with conventional dressing methods, the medical screen can be used as a novel way to decrease the negative experience of burn patients -ages 1–3 who require dressing changes.

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The medical screen is likely a feasible, acceptable and potentially efficacious treatment option for burns medical workers.

Objective

To evaluate the impact of the specially designed medical dressing screen during wound dressing changes of children who suffered burns to their hand or foot.

Design

Randomized controlled trial.

Setting

Burns and Plastic Reconstruction Unit.

Participants

Children (NN = 120) with burns on up to 1%-–5% of the total body surface area.

Interventions

The patients were selected and randomly allocated to 3 equal-sized groups as follows:control group (N control group (N = 40): the children received only regular dressing changes; computer group (NN = 40): a touch-screen computer was used for children during dressing changes; medical screen group (NN = 40): a medical screen combined with the touch-screen computer were used for children during dressing changes. All patients underwent a dressing change once per day for four days. Data were distributed four times: immediately after the initial dressing change (T1); and immediately after each times at next three consecutive days (T2-T4).Main Outcome M–T4).

Main outcome measures

The Pain level of the children evaluated by medical staffs was the primary outcome, the Pain level of the children evaluated by children's parents and the satisfaction of wound therapist were used as second outcomes.

Results

The mean scores related to pain level at the medical screen group displayed significantly better results than those of control group and those of the computer group. Additionally, the results of the pain evaluated by parents and satisfaction score of the wound therapist at the medical screen group was also better than other groups.

Conclusions

This study demonstrated “that the” application of the medical screen for burns can relieve the pain of 1-–3 years old children suffering from a burns during dressing changes. Additionally, the application of the medical screen also increased the satisfaction of the parents and the wound therapist performing the dressing changes.

The underlying changes and predicting role of peripheral blood inflammatory cells in severe COVID-19 patients: A sentinel?

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Lymphopenia and eosinopenia might be predictors of disease severity in COVID-19.

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Lymphopenia and eosinopenia might be predictors of disease progression in COVID-19.

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Clinical classification-severe type is the dependently risk factor for alteration of PBICs.

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PBICs might be a sentinel, and it deserves attention during COVID-19 management.

Background

The underlying changes of peripheral blood inflammatory cells (PBICs) in COVID-19 patients are little known. Moreover, the risk factors for the underlying changes of PBICs and their predicting role in severe COVID-19 patients remain uncertain.

Material and methods

This retrospective study including two cohorts: the main cohort enrolling 45 patients of severe type serving as study group, and the secondary cohort enrolling 12 patients of no-severe type serving as control group. The PBICs analysis was based on blood routine and lymphocyte subsets. The inflammatory cell levels were compared among patients according to clinical classifications, disease-associated phases, as well as one-month outcomes.

Results

Compared with patients of non-severe type, the patients of severe type suffered from significantly decreased counts of lymphocytes, eosinophils, basophils, but increased counts of neutrophils. These PBICs alterations got improved in recovery phase, but persisted or got worse in aggravated phase. Compared with patients in discharged group, the patients in un-discharged/died group suffered from decreased counts of total T lymphocytes, CD4 + T lymphocytes, CD8 + T lymphocytes, as well as NK cells at 2 weeks after treatment. Clinical classification-critically severe was the independently risk factor for lymphopenia (OR = 7.701, 95%CI:1.265–46.893, P = 0.027), eosinopenia (OR = 5.595, 95%CI:1.008–31.054, P = 0.049), and worse one-month outcome (OR = 8.984; 95%CI:1.021–79.061, P = 0.048).

Conclusion

Lymphopenia and eosinopenia may serve as predictors of disease severity and disease progression in COVID-19 patients, and enhancing the cellular immunity may contribute to COVID-19 treatment. Thus, PBICs might become a sentinel of COVID-19, and it deserves attention during COVID-19 treatment.

The complete chloroplast genome of Aloe vera from China as a Chinese herb

Aloe vera has been used as a Chinese herb and an ingredient in many cosmetic products in China. In this study, the complete chloroplast genome of A. vera was determined for more genetic data information. The chloroplast genome was 152,875 bp length as a typical quadripartite structure that contained a large single-copy region (LSC) of 83,505 bp, a small single-copy region (SSC) of 16,178 bp and a pair of inverted-repeat regions (IRs) of 26,596 bp. The overall nucleotide composition of chloroplast genome is: 47,185 bp A (30.8%), 48,123 bp T (31.5%), 29,326 bp C (19.2%), 28,241 bp G (18.5%) and the total G + C content of 37.7%. Then, 131 genes were found that included 85 protein-coding genes (PCGs), 38 transfer RNA (tRNAs) and 8 ribosome RNA (rRNAs). The phylogenetic analysis showed that A. vera closely related to A. maculata in the phylogenetic relationship of the family Asphodelaceae by the Maximum-Likelihood (ML) method.

lncRNA XIST promotes the progression of laryngeal squamous cell carcinoma by sponging miR‑144 to regulate IRS1 expression

The initiation and development of several types of cancer have been linked to long non‑coding RNA (lncRNA) X inactive‑specific transcript (XIST). Yet, the pattern of expression, function, as well as the molecular mechanism underlying XIST in laryngeal squamous cell carcinoma (LSCC) lack characterization. Therefore, the present study aimed to determine the function and putative mechanism of XIST in the development of LSCC. It was revealed that the level of XIST was significantly higher in LSCC tissues that were associated with advanced Tumor‑Node‑Metastasis (TNM) stage and the presence of lymph node metastasis. Furthermore, the ability of human LSCC TU212 cells to proliferate, form colonies, migrate and invade was significantly suppressed, while cell apoptosis was significantly increased following knockdown of XIST. Further investigation revealed that XIST knockdown increased the expression of microRNA‑144 (miR‑144) by acting as an endogenous sponge of miR‑144. Inhibition of miR‑144 caused a partial reversal of the inhibitory effects mediated following depletion of XIST in LSCC cells. Moreover, an miR‑144 target called insulin receptor substrate 1 (IRS1) was significantly decreased by XIST depletion in LSCC cells. IRS1 expression was positively correlated with XIST expression in LSCC tissues. In addition, knockdown of XIST impaired tumor growth in vivo by regulating the miR‑144/IRS1 axis. The present study demonstrated that the progression of LSCC is promoted by XIST sponging miR‑144 to regulate IRS1 expression, suggesting that XIST can serve as a putative target in the therapy of LSCC.

BRAF inhibitors: efficacious and tolerable in BRAF-mutant acral and mucosal melanoma

BRAF inhibitors substantially have impressive clinical efficacy in cutaneous melanoma. However, their role in acral and mucosal melanoma remains unclear. Records were reviewed of patients with metastatic or unresectable BRAF-mutant acral and mucosal melanoma hospitalized and administrated BRAF inhibitors during January 2011 and March 2016. Clinical data were collected to determine PFS, ORR, DCR, OS, and safety. Among 28 acral and 12 mucosal melanoma patients treated with BRAF inhibitors, median PFS were 3.6 (95%CI 3.0-6.4) and 4.4 (95%CI 0.8-12.7) months, median OS were 6.2 (95%CI 6.1-12.1) and 8.2 (95%CI 6.6-19.9) months; ORRs were 38.1% and 20.0%, DCRs were 81.0% and 70.0% in acral and mucosal melanoma, respectively. BRAF inhibitors were well tolerated. The most common adverse effects (AEs) were cutaneous and hematological. Grade 3/4 AEs were relatively rare. In conclusion, BRAF inhibitors have acceptable efficacy and good tolerance in BRAF mutant acral and mucosal melanoma.

[Impact of first-line chemotherapy on renal function in patients with advanced upper tract urothelial carcinoma]

Objective: To observe the impact of first-line chemotherapy on renal function in patients with unresectable/metastatic upper tract urothelial carcinoma(UTUC). Methods: A total of 222 (130 males and 92 females) unresectable/metastatic upper tract urothelial carcinoma patients were included in the study between January 2005 and May 2017, with age of 29 to 87 (62.4±10.1) years old. The serum creatinine level and estimated glomerular filtration rate (eGFR) were compared before and after first-line chemotherapy. And predictive factors for decreased renal function were analyzed in logistic regression model. Results: After the first-line chemotherapy, the average serum creatinine level increased, with a median changing value of 1.5 μmol/L. Howerver, the eGFR improved, with a median changing value of 0.5 ml·min^-1· (1.73 m²)^-1, but the differences were not statistically significant (all P>0.05). In 149 patients who were treated with cisplatin-based chemotherapy, the average serum creatinine level increased by 1.31 μmol/L and eGFR improved by 0.14 ml·min^-1·(1.73 m²)^-1, but the differences were not statistically significant (P>0.05). In multivariate logistic regression model, age more than and equal to 60 years old (OR=0.88, P=0.745) and cisplatin-based chemotherapy (OR=0.95, P=0.893) did not increase the risk of renal dysfunction after first-line chemotherapy. If the time interval between surgery and first-line chemotherapy was more than 1 year, the risk of renal dysfunction due to chemotherapy decreased (OR=0.54, P=0.196). Eastern Cooperative Oncology Group Performance Status (ECOG PS) Scale≥1 (OR=1.81, P=0.131), anemia before treatment (OR=1.14, P=0.764), the cycles of first-line chemotherapy (OR=1.41, P=0.398) may lead to increase the risk of renal dysfunction, but the differences were not statistically significant. However in the patients who accepted nephrectomy, the risk of renal dysfunction after chemotherapy increased, but the difference was still not statistically significant (OR=3.06, P=0.089). Conclusions: First-line chemotherapy, especially the cisplatin-based regimen, had no significant impact on renal function in the patients with UTUC. Nephrectomy maybe a predictive risk factor for decreased renal function after chemotherapy. Adequate assessment of renal function before treatment, hydration and close monitoring during chemotherapy can effectively protect renal function of the patients.

[The invasive fungal rhino-sinusitis cased by aspergillus nidulans: one case report]

This report described a case of the invasive fungal sinusitis cased by asperigillus. A 51 years old women patient complained a sense of welling on right facial, mild pain. No complain of facial numbness and toothache. During the 2 months the symptom repeatedly occurrence. A combined treatment including endoscopic sinus surgery (ESS) and anti fungal therapy was performed in a patient with invasive fungal rhino sinusitis. After 3 months of operation, the patient recovered well. No recurrence, no jaw facial pain and swelling, no eye movement disorder.

miR-144 suppresses the growth and metastasis of laryngeal squamous cell carcinoma by targeting IRS1

Increasing evidence has been suggested that microRNA-144 (miR-144) involved in tumor initiation, development and metastasis in various cancers. However, the biological roles and potential mechanisms of miR-144 in laryngeal squamous cell carcinoma (LSCC) remain unclear. In the present study, we discovered that miR-144 expression levels in LSCC tissues were significantly lower than those of adjacent normal tissues. Furthermore, overexpression of miR-144 in LSCC cells inhibited cell proliferation, colony formation, migration, and invasion in vitro. Consistently, stable overexpression of miR-144 suppressed the growth of LSCC cell xenografts in vivo. Bioinformatic algorithms and luciferase reporter assays confirmed that insulin receptor substrate 1 (IRS1) is a direct target of miR-144. Overexpreesion of miR-144 obviously decreased IRS1 expression thereby suppressing phosphatidylinositol 3-kinase (PI3K)/AKT pathway activation. Further functional studies suggested that downregulation of IRS1 had similar effects as that of miR-144 overexpression, and upregulation of IRS1 partially reversed the inhibitory effects of miR-144. These findings suggested that miR-144 functioned as a tumor suppressor in LSCC by targeting IRS1, and that miR-144 might serve as a potential target for LSCC treatment.

Impact of Protein Nutritional Status on Plasma BNP in Elderly Patients

BACKGROUND

Previous studies have demonstrated that the levels of B-type natriuretic peptide (BNP) in plasma are negatively correlated with Body Mass Index (BMI) whereas lean body mass is also closely related to plasma BNP. The purpose of this study is to determine the effect of protein nutritional status on plasma BNP in aged patients.

METHODS AND RESULTS

The cross-sectional study was applied and the anthropometric measurement and nutritional biochemical test was performed in 1118 elderly inpatients in a stable condition were enrolled in the study (mean age, 75 years; 54% women). The partial correlation and multivariate regression analysis were conducted to analyze the relation of plasma BNP with covariates. After adjustment for confounding factors such as age, smoking and coexisting diseases, we found that the concentrations of BNP were independently associated with serum albumin (β=-0.065, P<0.001), serum total cholesterol (β=-0.097, P<0.012) and calf circumference (β=-0.032, P<0.014) in female patients, and associated with the serum albumin (β=-0.051, P<0.001), prealbumin (β=-2.177, P<0.026), mid-arm circumference (β=-0.062, P<0.001) and grip strength (β=-0.100, P<0.048) in male patients. Every 1 gram per liter of increased serum albumin corresponded to the reduced plasma BNP in male patients by 13.9% (OR 0.861, 95% CI 0.817, 0.909) and in female patients by 13.4% (OR 0.866, 95% CI 0.819, 0.916).

CONCLUSIONS

Our study suggests that plasma BNP is negatively correlated with muscle mass, and it is also related to muscle force in male patients. The serum albumin is an independent determinant factor of BNP in both men and women. These findings suggest that good protein nutritional status could be beneficial in maintaining the cardiac function in elder population.

Anatomical information for intercostobrachial nerve preservation in axillary lymph node dissection for breast cancer

This study aimed to provide additional anatomical information for axillary lymph node dissection (ALND) through in vivo anatomy studies of intercostobrachial nerve (ICBN) preservation in order to provide theoretical and practical experience for clinicians. A total of 156 patients with breast cancer underwent ALND at the Department of Gynecology of Baotou Tumor Hospital between June 2009 and March 2010. The origin, destination, main source, length, branch type, and direction of ICBN in axilla were observed, as well as its relationship with adjacent major blood vessels and nerves within the axilla. There were 120 cases of single trunk, 23 cases of double trunks, 9 cases of multiple trunks, and 4 cases without trunks in 156 patients with ICBN preservation. The transverse diameter at the origin of the ICBN was 1.89 ± 0.44 mm with a length of 94.45 ± 12.08 mm; the distances were 77.19 ± 21.04 mm, 29.34 ± 6.73 mm, 90.04 ± 13.13 mm, and 28.63 ± 13.01 mm from origin to the inferior margin at the midpoint of the clavicle, inferior margin of the axillary vein, the bottom of axilla, and branch point, respectively. The identification, dissection, and preservation of ICBN was simple and easy in a modified radical mastectomy for breast cancer and breast-conserving surgery, which only took 10-20 min, but effectively reduced the incidence of post-mastectomy pain syndrome and significantly improved the quality of life for patients after surgery.

[Correlation between motor paralysis and neurotoxicity induced by intrathecal dynorphin A (1-17) in rats]

Intrathecal(i.t.) injection of 10 microliters of dynorphin A(1-17) 20 nmol.L-1 per rat resulted in irreversible hind limb paralysis and suppression of the tail-flick reflex lasting for up to 40 h. The dual effects of dynorphin appeared 5-10 min after the i.t. administration. Histologic examination of the spinal cord in the rats demonstrated dead and/or dying and degenerated motor-neurons in the ventral horn located predominately in the lumbar segment(a 87.2% reduction of the number of motor neurons, P < 0.01) and also in a lesser degree in sacral segment(-69.6%, P < 0.05). The thoracic segment was essentially normal(-8.2%, P > 0.05).

Spinal kappa-opioid system plays an important role in suppressing morphine withdrawal syndrome in the rat

To explore the possible involvement of spinal kappa-opioid receptor in modulating morphine withdrawal syndrome, rats were made dependent on morphine by multiple injections of morphine HCl for 5 days. They were then given intrathecal administration (i.t.) of a kappa-opioid receptor agonist trans-3, 4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl]-benzenacetamide hydrochloride (U-50,488H, 2.5-10 microg) or its antagonist nor-binaltorphimine (nor-BNI, 1.25-5 microg), followed by intraperitoneal administration (i.p.) of naloxone (0.5 mg/kg), and the withdrawal syndrome was scored for 60 min. U-50,488H produced a dose-dependent suppression, whereas nor-BNI a dose-dependent potentiation in withdrawal syndrome. The latter result implies that an endogenous kappa receptor agonist, most probably dynorphin, exerts a tonic suppressive effect on morphine syndrome at spinal level.

Suppression of morphine withdrawal by electroacupuncture in rats: dynorphin and kappa-opioid receptor implicated

Our previous work has demonstrated that 100-Hz electroacupuncture (EA) or 100-Hz transcutaneous electrical nerve stimulation (TENS) was very effective in ameliorating the morphine withdrawal syndrome in rats and humans. The mechanism was obscure. (1) Rats were made dependent on morphine by repeated morphine injections (5-140 mg/kg, s.c., twice a day) for eight days. They were then given 100-Hz EA for 30 min 24 h after the last injection of morphine. A marked increase in tail flick latency (TFL) was observed. This effect of 100-Hz EA could be blocked by naloxone (NX) at 20 mg/kg, but not at 1 mg/kg, suggesting that 100-Hz EA-induced analgesia observed in morphine-dependent rats is mediated by kappa-opioid receptors. (2) A significant decrease of the concentration of dynorphin A (1-17) immunoreactivity (-ir) was observed in the spinal perfusate in morphine-dependent rats, that could be brought back to normal level by 100-Hz EA. (3) 100-Hz EA was very effective in suppressing NX-precipitated morphine withdrawal syndrome. This effect of EA could be prevented by intrathecal administration of nor-BNI (2.5 micrograms/20 microliters), a kappa-opioid receptor antagonist, or dynorphin A (1-13) antibodies (25 micrograms/20 microliters) administered 10 min prior to EA. In conclusion, while the steady-state spinal dynorphin release is low in morphine-dependent rats, it can be activated by 100-Hz EA stimulation, which may be responsible for eliciting an analgesic effect and ameliorating morphine withdrawal syndrome, most probably via interacting with kappa-opioid receptor at spinal level.