Currently available μ-opioid receptor agonist pharmacotherapies for opioid use disorder possess adverse effects limiting their use, and despite treatment, rates of relapse remain high. We previously showed that endomorphin analog ZH853 had no effect in rodent models that predict abuse liability in humans. Here we extended these findings by examining dependence liability and reinforcing properties in female rats and male rats with previous opioid exposure. The potential use of ZH853 in managing opioid use disorder was evaluated by examining its effect on opioid-seeking behavior and withdrawal. We found that ZH853 did not induce locomotor activation in male and female mice and was not self-administered by female rats. Relative to morphine, ZH853 led to similar somatic signs of withdrawal, but low affective-motivational signs of withdrawal, and absent changes in ventral tegmental area K(+)-Cl(-) co-transporter expression associated with reward dysregulation. The low abuse liability of ZH853 was further supported in oxycodone self-administering male rats, where ZH853 substitution extinguished opioid-seeking behavior. ZH853 priming also did not reinstate morphine conditioned place preference. Lastly, ZH853 inhibited oxycodone-seeking behavior during relapse after forced abstinence and decreased the expression of morphine withdrawal. These findings suggest the potential use of ZH853 as a safer opioid medication for long-term treatment of pain and opioid use disorder.

Despite the available knowledge on underlying mechanisms and the development of several therapeutic strategies, optimal management of postoperative pain remains challenging. This pre-clinical study hypothesizes that, by promoting an anti-inflammatory scenario, pre-emptive administration of IMT504, a non-coding, non-CpG oligodeoxynucleotide with immune modulating properties, will reduce postincisional pain, also facilitating therapeutic opioid-sparing. Male adult Sprague-Dawley rats with unilateral hindpaw skin-muscle incision received pre-emptive (48 h and 24 h prior to surgery) or postoperative (6h after surgery) subcutaneous vehicle (saline) or IMT504. Various groups of rats were prepared for pain-like behaviour analyses, including subgroups receiving morphine or naloxone, as well as for flow-cytometry or quantitative RT-PCR analyses of the spleen and hindpaws (for analysis of inflammatory phenotype). Compared to vehicle-treated rats, pre-emptive IMT504 significantly reduced mechanical allodynia by 6 h after surgery, and accelerated recovery of basal responses from 72 h after surgery and onwards. Cold allodynia was also reduced by IMT504. Postoperative administration of IMT504 resulted in similar positive effects on pain-like behaviour. In IMT504-treated rats, 3 mg/kg morphine resulted in comparable blockade of mechanical allodynia as observed in vehicle-treated rats receiving 10 mg/kg morphine. IMT504 significantly increased hindpaw infiltration of mesenchymal stem cells, CD4+T and B cells, and caused upregulated or downregulated transcript expressions of interleukin-10 and interleukin-1β, respectively. Also, IMT504 treatment targeted the spleen, with upregulated or downregulated transcript expressions, 6 h after incision, of interleukin-10 and interleukin-1β, respectively. Altogether, pre-emptive or postoperative IMT504 provides protection against postincisional pain, through participation of significant immunomodulatory actions, and exhibiting opioid-sparing effects.

Protein S is a vitamin K-dependent protein that acts as a break in secondary hemostasis by inactivating activated factor V and activated factor VIII. We report a case of a 40 years old male who had the first episode of deep vein thrombosis of the left lower limb 10 years back, which despite treatment, reoccurred 3 months later in the bilateral lower limb. Thrombophilic screening showed severe protein S deficiency. The patient then developed deep vein thrombosis of both upper limbs. The patient was advised to place an inferior vena cava filter, which he denied. The patient is now presenting with multiple episodes of post-thrombotic syndrome. Such attacks are treated with elastic compression stockings, rivaroxaban, and morphine. However, despite medication, the pain has not yet subsided. Hence, even though protein S deficiency is the rare cause of deep vein thrombosis when recurrent should be considered despite its rare occurrence.

The use of opioids to control pain at the end of life may cause constipation, a symptom that can negatively influence the well-being of patients and caregivers. The main aim of this study was to evaluate the impact of constipation on symptomatic control and patients' overall quality of life at this stage. A particular focus was placed on opioids. We also intended to investigate whether constipation and caregiver fatigue is related to the place of death (hospital vs home). The approach of 121 patients followed in 2021 in their last week of life by a home team specialized in palliative care was analyzed in an observational, retrospective, non-interventional study. The patients were followed up for an average of 39.7 days. A total of 82.6% wished to die at home, which occurred in 74% of the cases. The constipation prevention protocol reduced constipation by 55.1%. It seems that morphine is more related with constipation and tapentadol seems to reduce constipation induced by opioids. Patients tended to die in hospitals when their caregivers were exhausted; however, it was not possible to determine a cutoff point using the Zarit scale, which was used to assess caregiver burden. Constipation in the last week of life does not seem to influence the well-being of patients or their caregivers significantly and the individualization of intensive treatment of constipation is needed. Different opioids have different probabilities of causing adverse effects such as constipation. Future special support mechanisms can be created and activated for the most tired caregivers to avoid exhaustion and promote death at home, if that is the patient's will.

Patient-controlled analgesia (PCA) appears to be the preferred modality for treatment of pain associated with vaso-occlusive crisis (VOC) and is the current standard of therapy at most institutions. With limited data available, this study analyzed the effectiveness of PCA vs intravenous push (IVP) hydromorphone for pain management of VOC. The primary objective was to determine whether PCA or IVP hydromorphone is more effective in controlling VOC pain determined by a reduction in mean absolute difference pain intensity (MPI) from baseline to discharge. This retrospective single-center study evaluated differences in outcomes between patients treated with PCA vs those treated with IVP hydromorphone for VOC during hospital admission. Those 18 years or older admitted with one of the following International Classification of Diseases, Tenth Revision codes were included: D57.0 (Hb-SS disease with crisis), D57.2 (sickle cell/Hb-C disease), and D57.4 (sickle cell thalassemia), and administered PCA or IVP hydromorphone. The observed difference in absolute pain scores were not statistically significant (p = 0.753). The use of IVP hydromorphone resulted in a significant reduction in length of stay (LOS) and morphine milligram equivalent (MME) use compared to PCA, but was associated with a numerical increase in treatment failures. This study was limited by its retrospective nature, uneven distribution of groups, and only reviewed use of IVP and PCA hydromorphone at one institution.

BACKGROUND Unwashed or unprocessed poppy seeds may be an underrecognized substance that can lead to dependence, abuse, and an opioid use disorder. Poppy seeds can be purchased in an unwashed or unprocessed form, and these seeds can be contaminated with the opium alkaloids morphine, codeine, and thebaine on their surfaces. Poppy seeds that are commercially available, such as those used for baking and in other food products, are legal to purchase, as they do not contain the opium alkaloids on their seed coats. Purchase and possession of the unwashed or unprocessed seeds are not legal in the United States. These contaminated poppy seeds can then be put through a process in which they are washed, and the supernatant (tea) is collected and consumed to experience its intoxicating effect or for the treatment of pain or opioid withdrawal. CASE REPORT A 65-year-old man with a history of alcohol use disorder, cannabis use, and chronic pain began using this poppy seed tea for treatment of chronic pain after his provider had stopped prescribing opioid pain medications for him. He developed a dependence on the tea. He had reached out for assistance as it was his desire to stop using the poppy seed tea. The diagnosis of an opioid use disorder was made using the DSM-V criteria. He was successfully induced and maintained on a buprenorphine/naloxone product. CONCLUSIONS Poppy seeds in their unwashed and unprocessed form can be misused and could lead to an opioid use disorder. This disorder can be treated with buprenorphine/naloxone products.

Carfentanil, as a fentanyl analogue, is a potent synthetic opioid. It has been controlled in many countries, and its emergence has been highlighted by many recent reports. However, although discriminative stimulus effects of carfentanil in rats had been reported, its abuse potential has not been fully evaluated. In this study, we evaluated the abuse potential of carfentanil via the tests of conditioned place preference (CPP), drug self-administration and naloxone-precipitated opioid withdrawal assay, compared with fentanyl and heroin. Carfentanil exhibited significant place preference at a minimum dose of 1 μg/kg in mice, whereas fentanyl and heroin induced significant place preference at the minimum doses of 100 μg/kg and 1000 μg/kg, respectively. In the drug-substitution test in heroin self-administered rats (50 μg/kg/infusion), carfentanil and fentanyl acquired significant self-administrations above saline levels from 0.05-0.1 and 0.1-10.0 μg/kg/infusion, respectively. Carfentanil induced the maximum number of infusions at 0.1 μg/kg, whereas fentanyl and heroin at 1 and 25 μg/kg, respectively. In short, carfentanil showed the highest potency to induce CPP and self-administration. Furthermore, repeated treatment with escalating doses of carfentanil, fentanyl or heroin induced typical withdrawal symptoms in mice, including a greater number of jumping and weight loss than saline group. This indicated that carfentanil could produce physical dependence similar to fentanyl and heroin. Taken together, the present study demonstrated the higher abuse potential of carfentanil compared with fentanyl and heroin. The rank order of abuse potential for these compounds is carfentanil > fentanyl > heroin.

Hemorrhage is a leading cause of preventable battlefield and civilian trauma deaths. Ketamine, fentanyl, and morphine are recommended analgesics for use in the prehospital (i.e., field) setting to reduce pain. However, it is unknown whether any of these analgesics reduce hemorrhagic tolerance in humans. We tested the hypothesis that fentanyl (75 µg) and morphine (5 mg), but not ketamine (20 mg), would reduce tolerance to simulated hemorrhage in conscious humans. Each of the three analgesics was evaluated independently among different cohorts of healthy adults in a randomized, crossover (within drug/placebo comparison), placebo-controlled fashion using doses derived from the Tactical Combat Casualty Care Guidelines for Medical Personnel. One minute after an intravenous infusion of the analgesic or placebo (saline), we employed a pre-syncopal limited progressive lower-body negative pressure (LBNP) protocol to determine hemorrhagic tolerance. Hemorrhagic tolerance was quantified as a cumulative stress index (CSI), which is the sum of products of the LBNP and the duration (e.g., [40 mmHg x 3 min] + [50 mmHg x 3 min] …). Compared with ketamine (p = 0.002 post hoc result) and fentanyl (p = 0.02 post hoc result), morphine reduced the CSI (ketamine (n = 30): 99 [73-139], fentanyl (n = 28): 95 [68-130], morphine (n = 30): 62 [35-85]; values expressed as a % of the respective placebo trial's CSI; median [IQR]; Kruskal-Wallis test p = 0.002). Morphine-induced reductions in tolerance to central hypovolemia were not well explained by a prediction model including biological sex, body mass, and age (R2=0.05, p = 0.74). These experimental data demonstrate that morphine reduces tolerance to simulated hemorrhage while fentanyl and ketamine do not affect tolerance. Thus, these laboratory-based data, captured via simulated hemorrhage, suggest that morphine should not be used for a hemorrhaging individual in the prehospital setting.

While surgical outcomes of prophylactic salpingectomy as an ovarian cancer risk reducing measure at the time of hysterectomy for benign indications has already been studied, data has traditionally been extrapolated to surgery for prolapse repair. A retrospective chart review was performed from medical records of patients who had undergone a sacrocolpopexy for pelvic organ prolapse. Variables collected included operation duration, length of hospital stay, readmission within 31 days, estimated blood loss (EBL), number and size of incisions, as well as narcotic use during hospitalization. Additional procedures performed at the time of operation including vaginal or laparoscopic hysterectomy, transobturator sling, anterior or posterior colporrhaphy, cystoscopy, and robotic ventral mesh rectopexy were collected as potential confounding variables. In addition, data to allow examination of pathology results of all fallopian tubes was collected to determine the proportion of pre-malignant and malignant pathology results. Statistical analyses were performed using SAS version 8. Two cohorts were created: (1) Patients who underwent adnexal surgery (bilateral salpingectomy or salpingoopherectomy) at time of the sacrocolpopexy and (2) Patients who underwent a sacrocolpopexy without adnexal surgery. Comparisons were performed with chi-square analysis for discrete variables and group t-tests for continuous level data. Narcotics administered during the immediate post-operative period until discharge was collected for each patient and converted to morphine milligram equivalents (MME) via multiplying the administered dose by the CDC established evidence-based conversion factor. Analysis of covariance (ANCOVA) as well as logistic regression was used to control for confounding variables, including the additional procedures patients had during their operation. An omnibus p-value of 0.05 was used to determine statistical significance for all tests. Due to the exploratory nature of this analysis, there were no corrections applied for multiple comparisons. This data can be used as a basis for researchers to build upon when assessing ovarian cancer primary prevention strategies and associated treatment modalities.

Twenty-eight grayanane diterpenoids (1-28) including 13 new ones, named daublossomins A-M (1-13), and two new natural products, 3-O-acetylgrayanotoxin II (14) and 10-epi-grayanotoxin III (15), were isolated from the flowers of Rhododendron dauricum L. (Ericaceae). Their structures were elucidated by means of comprehensive spectroscopic methods and quantum chemical calculations (13C NMR-DP4+ analysis and calculated ECD), and the absolute configurations of ten grayanane diterpenoids 1, 4, 5, 7, 8, 22, 23, 25, 27, and 28 were determined by X-ray crystallographic analysis. Daublossomin A (1) represents the first example of an 11,16-epoxygrayan-6-one diterpenoid. Daublossomins B (2) and C (3) are the first examples of 9β,10β-epoxygrayanane diterpenoids, and daublossomin I (9) is the second conjugated grayan-1(5),6(7),9(10)-triene diterpenoid. Compounds 1-11 and 13-27 were evaluated for their analgesic activities in the HOAc-induced writhing test in mice, and 1-8, 10, 11, 13, 15, 17, 18, 22-24, and 26 exhibited significant analgesic effects at a dose of 5.0 mg/kg (inhibition rates > 50%). Among them, daublossomins A (1) and F (6) still showed potent analgesic activity even at a lower dose of 0.2 mg/kg with the inhibition rates of 54.4% and 55.2%, respectively. Grayanotoxin III (20) showed more potent analgesic activities than the positive control, morphine, at a dose of 0.04 mg/kg. A preliminary structure-activity relationship for the analgesic grayanane diterpenoids was discussed, providing some useful clues to design and develop structurally novel potent analgesics.

Dysfunction of the central nervous system are accompanied by changes in tryptophan metabolism, with the kynurenine pathway (KP) being the main route of its catabolism. Recently, KP metabolites, which are collectively called kynurenines, have become an area of intense research due to their ability to directly and indirectly affect a variety of classic neurotransmitter systems. However, the significance of KP in neuropathic pain is still poorly understood. Therefore, we designed several experiments to verify changes in the mRNA levels of KP enzymes in parallel with other factors related to this metabolic route after chronic constriction injury of the sciatic nerve (CCI model) in mice. The analysis revealed an increase in, Kmo, Kynu and Haoo mRNA levels in the spinal cord on the 7th day after CCI, while Kat1, Kat2, Tdo2, Ido2 and Qprt mRNA levels remain unchanged. Subsequent pharmacological studies provided evidence that modulation of KP by single intrathecal administration of 1-D-MT, UPF468 or L-kynurenine attenuates mechanical and thermal hypersensitivity and increases the effectiveness of selected opioids in mice as measured on day 7 after CCI. Moreover, our results provide the first evidence that the injection of L-kynurenine preceded by UPF468 (KMO inhibitor) is more effective at reducing hypersensitivity in animals with neuropathic pain. Importantly, L-kynurenine also exerts an analgesic effect after intravenous injections, which is enhanced by the administration of minocycline, an inhibitor of microglial activation. Additionally, L-kynurenine administered intrathecally and intravenously enhances analgesia evoked by all tested opioids (morphine, buprenorphine and oxycodone). Overall, our results indicate that the modulation of KP at different levels might be a new pharmacological tool in neuropathy management.