Quasi-Static, Poiseuille Flow of Analgesics from an Elastomeric Pump: Theoretical Determination of Infusion Times and Toxicity Conditions

Background: Elastomeric pumps (elastic balls into which analgesics or antibiotics can be inserted) push medicines through a catheter to a nerve or blood vessel. Since elastomeric pumps are small and need no power source, they fit easily into a pocket during infusion, allowing patient mobility. Elastomeric pumps are widely used and widely studied experimentally, but they have well-known problems, such as maintaining reliable flow rates and avoiding toxicity or other peak-and-trough effects. Objectives: Our research objective is to develop a realistic theoretical model of an elastomeric pump, analyze its flow rates, determine its toxicity conditions, and otherwise improve its operation. We believe this is the first such theoretical model of an elastomeric pump consisting of an elastic, medicine-filled ball attached to a horizontal catheter. Method: Our method is to model the system as a quasi-Poiseuille flow driven by the pressure drop generated by the elastic sphere. We construct an engineering model of the pressure exerted by an elastic sphere and match it to a solution of the one-dimensional radial Navier-Stokes equation that describes flow through a horizontal, cylindrical tube. Results: Our results are that the model accurately reproduces flow rates obtained in clinical studies. We also discover that the flow rate has an unavoidable maximum, which we call the “toxicity bump”, when the radius of the sphere approaches its terminal, unstretched value—an effect that has been observed experimentally. Conclusions: We conclude that by choosing the properties of an elastomeric pump, the toxicity bump can be restricted to less than 10% of the earlier, relatively constant flow rate. Our model also produces a relation between the length of time that the analgesic fluid infuses and the physical properties of the fluid, of the elastomeric sphere and the tube, and of the blood vessel into which the analgesic infuses. From these, we conclude that elastomeric pumps can be designed, using our simple model, to control infusion times while avoiding toxicity effects.

Design, Synthesis of Analgesics and Anticancer of Some New Derivatives of Benzimidazole

This work, contains some new compounds from benzimidazole derivatives, which are synthesized by condensation of Orthophenylene diamine and Carbon disulfide resulting in 2-Mercapto-benzimidazole which is treated by alcoholic potassium hydroxide forming potassium salt of 2-mercaptobenzimidazole which reacts with different substances (alkyl chloroacetates, chloroacetic chloride, alkyl halides) also the ethoxy carbonyl methyl thiobenzimidazole reacts with different amines. In addition to chloromethyl benzimidazole which resulted from the reaction between orthophenylene diamine and chloroacetic acid, which reacted with different amines. The synthesized compound tested as analgesics and anticancer activity the new derivatives revealed moderate, strong and very strong analgesics and moderate and strong anticancer activity.

Expert consensus of Chinese Association for the Study of Pain on the non-opioid analgesics for chronic musculoskeletal pain

Chronic musculoskeletal pain(CMP)is a common occurrence in clinical practice and there are a variety of options for the treatment of it.However,the pharmacological therapy is still considered to be a primary treatment.The recent years have witnessed the emergence of opioid crisis,yet there are no relevant guidelines on how to treat CMP with non-opioid analgesics properly.The Chinese Medical Association for the Study of Pain convened a panel meeting to develop clinical practice consensus for the treatment of CMP with non-opioid analgesics.The purpose of this consensus is to present the application of nonsteroidal antiinflammatory drugs,serotonin norepinephrine reuptake inhibitors,serotonin and norepinephrine reuptake inhibitors,muscle relaxants,ion channel drugs and topical drugs in CMP.

Analgesic and anti-inflammatory activity of Cotinus coggygria Scop.extracts in vivo

Objective:To assess the analgesic and anti-inflammatory effects of standardized extract of Cotinus coggygria(C.coggygria)in different animal models.Methods:C.coggygria extracts(25,50,and 100 mg/kg)were administered to rats and mice(n=6)during hot plate,tail-flick,acetic acid-induced writhing,and formalin tests to determine its analgesic efficacy.The anti-inflammatory activity of C.coggygria extracts was evaluated by histamine and carrageenan-induced paw edema,cotton pellet-induced granuloma,and acetic acid-induced peritoneal capillary dye leakage tests.Results:C.coggygria extracts(50 and 100 mg/kg)significantly alleviated thermal and chemical-induced pain in rodents(P<0.05).It also demonstrated notable anti-inflammatory properties by mitigating histamine and carrageenan-induced paw edema,granuloma deposits,and vascular permeability(P<0.05).Moreover,C.coggygria extracts remarkably reduced TNF-α,IL-1β,IL-6,COX-2,and oxidative stress in rat paws(P<0.05).Carrageenan-induced histological aberrations in hind paw tissues were effectively(P<0.05)mitigated by treatment with C.coggygria extracts.Conclusions:C.coggygria Scop.extracts show analgesic and anti-inflammatory effects via inhibition of COX-2 and inflammatory and oxidative mediators.

Research Progresses in Effects of Analgesics and Sedatives on Intracranial Pressure of Neurointensive Care Patients

At present, there are some concerns and problems to treat neurointensive care patients by using analgesics and sedatives. Conditions of neurointensive care patients change quickly. For neurointensive care patients who cannot have auxiliary examination timely, clinicians judge intracranial conditions mainly through relevant monitoring devices and consciousness and pupil changes of patients. The use of analgesics and sedatives is limited due to worry about influences on consciousness evaluation and judgment and different degrees of inhibition on cardiovascular system and respiratory system. Common sedatives (e.g. benzodiazepines) and common analgesics (e.g. morphine, fentanyl and sufentanil) both may inhibit respiration. The specification often provides taboos for the use of drugs by patients with increase intracranial pressure (ICP) and craniocerebral injuries. Through literature review, the author analyzed influences of analgesics and sedatives on ICP of neurointensive care patients comprehensively.

Treatment with analgesics after mouse sciatic nerve injury does not alter expression of wound healingassociated genes

Animal models of sciatic nerve injury are commonly used to study neuropathic pain as well as axon regeneration. Administration of post-surgical analgesics is an important consideration for animal welfare, but the actions of the analgesic must not interfere with the scientific goals of the experiment. In this study, we show that treatment with either buprenorphine or acetaminophen following a bilateral sciatic nerve crush surgery does not alter the expression in dorsal root ganglion（DRG） sensory neurons of a panel of genes associated with wound healing. These findings indicate that the post-operative use of buprenorphine or acetaminophen at doses commonly suggested by Institutional Animal Care and Use Committees does not change the intrinsic gene expression response of DRG neurons to a sciatic nerve crush injury, for many wound healing-associated genes. Therefore, administration of post-operative analgesics may not confound the results of transcriptomic studies employing this injury model.

Gender Differences in Usage of Over-the-Counter Analgesics among Norwegian Adolescents

Introduction: Usage of over-the-counter (OTC) analgesic has increased among Norwegian adolescents since 2001. It has been noted that females tend to have a higher usage compared to males. In this paper we explore this gender difference. Data: Our dataset consists of 284,674 from Norwegian adolescents attending junior high school and high school between 2014 and 2017. Methods: The econometric approach consists of applying ordered logistic regressions with usage of OTC analgesics as the dependent variable and a dichotomous gender variable as the independent variable. Control variables include variables such as frequency of physical and mental health problems and other sociodemographic variables. Results: Gender, physical and mental health problems and various sociodemographic variables are found to have a significant effect on usage of OTC analgesics. Females are predicted to use significantly more analgesics. A large proportion of the gender difference evaporates when controlling for various other determinants. Conclusion: A considerable part of the observed gender difference in OTC analgesic usage can be traced back to differences in frequency and severity of physical and mental health problems. Part of the gender difference in usage, however remains unexplained.

Anticancer,Anti-inflammatory,Analgesic,and Anxiolytic Effects of Koumine and Their Molecular Mechanisms

Koumine is an indole alkaloid monomer extracted from the Chinese herb Gelsemium elegans,which has a variety of pharmacological effects.This paper provides a comprehensive summary of the pharmacological effects and molecular mechanisms of koumine,with a particular emphasis on its mechanisms of action in the context of anticancer,anti-inflammatory,analgesic,and anxiolytic properties.The aim is to provide a theoretical foundation for further research and the application of koumine in clinical practice.

Analgesic Effect of Combined Spinal-Epidural Anesthesia and its Effect on TNF-α and CRP Levels in Elderly Patients with Hip Fracture During Surgical Treatment

Objective:To observe the analgesic effect of combined spinal and epidural anesthesia on older patients undergoing hip fracture surgery.Method:One hundred and twenty elderly hip fracture surgery patients treated in our hospital from January 2021 to December 2022 were selected and randomly divided into two groups,with 60 cases in the experimental group and 60 in the control group.The experimental group was given combined spinal-epidural anesthesia intervention measures,while the control group was given epidural anesthesia intervention measures.The analgesic effect,tumor necrosis factor-alpha(TNF-α),C-reactive protein(CRP)levels,and other observation indicators were analyzed after anesthesia intervention.Result:After the intervention,the analgesic effect and the evaluation results of the subjects in the experimental group were better than those in the control group(P<0.05);the obtained values of TNF-αand CRP levels in the experimental group were higher than those of the control group(P<0.05).Conclusion:The combined spinal-epidural anesthesia intervention demonstrated positive outcomes.The analgesic effect of patients during surgery and their inflammatory factor levels improved,which makes this intervention worthy of clinical application and promotion.

Synthesis and analgesic activities studies on bispiperazinium (BPZ) salts

Selecting compound 97-9-G4 as lead compound, a series of bispiperazinittm salts 5a-h were designed, synthesized and evaluated for their analgesic activities. The results show that phenylethyl group of 97-9-G4 is a crucial pharmacophore; the intro- duction of electron-withdrawing group on benzene ring is favorable to the activity.

竖脊肌平面阻滞联合星状神经节阻滞在老年腹腔镜全子宫切除术中的应用效果

目的探究竖脊肌平面阻滞(ESPB)联合星状神经节阻滞(SGB)在老年腹腔镜全子宫切除术(LTH)中的应用效果。方法选取连云港市妇幼保健院2021—2023年收治的116例行LTH的老年病人,采用随机数表法分成2组,每组58例。在麻醉诱导前,对照组予以ESPB,联合组予以ESPB联合SGB。比较2组手术指标、麻醉药物用量、VAS评分、补救镇痛情况、术后恢复、应激指标、不良反应情况及麻醉诱导前(T0)、麻醉后5 min(T1)、术毕(T2)时刻的心率(HR)和平均动脉压(MAP)。结果2组手术时间、术中出血量、术后首次下床时间、住院时间及不良反应发生率差异均无统计学意义(P>0.05);联合组丙泊酚、舒芬太尼用量及镇痛泵按压次数、补救镇痛率、术后首次排气时间均低于对照组(P<0.05)。术后6、12、24 h,2组VAS评分均逐渐下降,且联合组低于对照组(P<0.05)。2组T1、T2时刻MAP、HR水平均较T0时刻升高,T2时刻较T1时刻下降,但联合组T1、T2时刻MAP、HR水平均低于对照组(P<0.05)。术后2组皮质醇(Cor)、P物质(SP)水平均高于术前,但联合组低于对照组(P<0.05)。结论行LTH的老年病人应用ESPB联合SGB可有效提升镇痛效果,减少镇痛药物用量,维持血流动力学稳定,减轻应激反应,且安全可靠。

Comparison of the analgesic effects between electro-acupuncture and moxibustion with visceral hypersensitivity rats in irritable bowel syndrome

AIM To observe whether there are differences in the effects of electro-acupuncture(EA) and moxibustion(Mox) in rats with visceral hypersensitivity. METHODS EA at 1 m A and 3 m A and Mox at 43?℃ and 46?℃ were applied to the Shangjuxu(ST37, bilateral) acupoints in model rats with visceral hypersensitivity. Responses of wide dynamic range neurons in dorsal horns of the spinal cord were observed through the extracellular recordings. Mast cells(MC) activity in the colons of rats were assessed, and 5-hydroxytryptamine(5-HT), 5-hydroxytryptamine 3 receptor(5-HT3R) and 5-HT4Rexpressions in the colons were measured.RESULTS Compared with normal control group, responses of wide dynamic range neurons in the dorsal horn of the spinal cord were increased in the EA at 1 m A and 3 m A groups(1 m A: 0.84 ± 0.74 vs 2.73 ± 0.65, P < 0.001; 3 m A: 1.91 ± 1.48 vs 6.44 ± 1.26, P < 0.001) and Mox at 43?℃ and 46?℃ groups(43?℃: 1.76 ± 0.81 vs 4.14 ± 1.83, P = 0.001; 46?℃: 5.19 ± 2.03 vs 7.91 ± 2.27, P = 0.01). MC degranulation rates and the expression of 5-HT, 5-HT3 R and 5-HT4 R in the colon of Mox 46?℃ group were decreased compared with model group(MC degranulation rates: 0.47 ± 0.56 vs 0.28 ± 0.78, P < 0.001; 5-HT: 1.42 ± 0.65 vs 7.38 ± 1.12, P < 0.001; 5-HT3R: 6.62 ± 0.77 vs 2.86 ± 0.88, P < 0.001; 5-HT4R: 4.62 ± 0.65 vs 2.22 ± 0.97, P < 0.001). CONCLUSION The analgesic effects of Mox at 46?℃ are greater than those of Mox at 43?℃, EA 1 m A and EA 3 m A.

Analgesic and anti-inflammatory activities of Passiflora foetida L.

Objective:To investigate the analgesic and anti-inflammatory activities of ethanol extract of Passiflora foetida(P.foetida) leaves.Methods:Ethanol extract of P.foetida leaf was evaluated for analgesic action by acetic acid-induced writhing and hot plate method in albino mice.The anti-inflammatory property of ethanolic leaf extract was tested by carrageenan induced acute paw edema and histamine induced acute paw edema in rats.Results:The dose 200 mg/kg of P. foetida leaf extract exhibited highest significant analgesic activity[(13.50±0.43) min]at a reaction time of 20 min in hot plate method in mice.The ethanol extract of leaf dose 100 mg/kg produced a highly significant anti inflammatory effect[(1.302±0.079) mL]in rats.Conclusions:It is very clear that P.foetida also has analgesic and anti-inflammatory activities for the pharmaceuticals.

Analgesic,anti-inflammatory and anti-diarrheal activities of ethanolic leaf extract of Typhonium trilobatum L.Schott

Objective:To explore the efficacy of ethanolic leaf extract of Typhonium trilobatum L.Schott in treating diarrhea,pain and inflammation using experimental models.Methods:In the present study,acetic acid-induced writhing,xylene-induced ear edema and castor oil-imluced diarrlieal model were used to evaluate the analgesic,anti-inflammatory and anti-diarrheal activities,respectively.Acute toxicity test was carried out to fix the safe doses of the plant extract.Results:The plant extract demonstrated a significant inhibition of writhing(P<0.01)compared with the control group in acetic acid-induced writhing test in mice.The extract also significantly inhibited the xylene induced ear edema formation(P<0.05).In anti-diarrheal test,the extract significantly decreased the frequency of defecation and increased the mean latent period(P<0.0l)in castor oil-induced diarrheal model mice at the doses of 250 and 500 mg/kg body weight.Conclusions:These results suggest that the extract possesses significant analgesic,anti-inflammatory and anti-diarrheal activities that support to the ethnopharmacologicl uses of this plant.

Analgesic and anti-inflammatory activities of the ethanol extract of the leaves of Helianthus Annus in Wistar rats

Objective:To investigate the anti-inflammatory and analgesic effects of the ethanol extract of leaves of Helianthus annus L.(H.annus) in acclimatized Wistar rats.Methods:It was undertaken using the albumin induced paw edema model of inflammation as well as both the hotplate and tail immersion analgesic test methods.Doses of the extract tested in experimental rats were 0.5 g/kg,2 g/kg and 4 g/kg while negative and positive control rats received distilled water and indomethacin respectively.Results:It was shown that treatment with the tested doses of the extract effectively inhibited paw edema induced by egg albumin.This effect was comparable if not better than the observations made in rats treated with 10 mg/kg of indomethacin orally.Treatment with the extract was also observed to have significantly increased the mean tolerance time of rats to thermal noxious stimuli compared to control animals that had distilled water and appeared to be more effective than 10 mg/kg of indomethacin treatment.Conclusions: These observations confirmed the presence of a strong anti-inflammatory and anti-noiciceptive activity in the ethanol extract of the leaves of H.annus and therefore validated the folkloric use of the leaves of this plant in treatment of pro-inflammatory,post traumatic situations.

Analgesic effect of parecoxib combined with ropivacaine in patients undergoing laparoscopic hepatectomy

BACKGROUND Currently, there is no uniform standard for analgesia during laparoscopic hepatectomy. Most of the analgesia schemes adopt epidural analgesia after laparotomy. Although the analgesia is effective, it has a great impact on the recovery of patients after laparoscopic hepatectomy and is not completely suitable for analgesia after laparoscopic hepatectomy. Although multimodal perioperative analgesia can significantly relieve postoperative pain, there is no relevant study of parecoxib combined with ropivacaine for post-laparoscopic hepatectomy analgesia.AIM To study the analgesic effect of the preoperative intravenous injection of parecoxib combined with long-acting local anesthetic ropivacaine for incision infiltration in patients undergoing laparoscopic hepatectomy.METHODS Forty-eight patients undergoing laparoscopic hepatectomy were randomly divided into a combined group (parecoxib combined with ropivacaine) and a control group. The visual analogue scale (VAS) at rest and during movement was used to compare the analgesic effect of the two groups. Meanwhile, the cumulative sufentanil, the recovery time for enterokinesia, the length of postoperative hospital stay, and the adverse reactions (nausea and vomiting)were recorded and compared between the two groups.RESULTSThe change tendency in VAS scores for both groups was similar after operation.At rest, the VAS scores of the combined group were significantly lower than those of the control group at 0, 6, 12, 24 and 36 h, and during movement, the VAS scores of the combined group were significantly lower than those of the control group at 0, 6, 12, and 24 h. The recovery time for enterokinesia in the combined group was 2.9 d, which was significantly shorter than that in the control group.The cumulative sufentanil in the combined group decreased significantly at 24,36, and 48 h after operation.CONCLUSION Preoperative intravenous injection of parecoxib combined with ropivacaine for incision infiltration is a simple and effective method for postoperative analgesia in laparoscopic hepatectomy, which could relieve pain and promote recovery.

Antioxidant,antimicrobial,cytotoxic and analgesic activities of ethanolic extract of Mentha arvensis L.

Objective:To investigate potential antioxidant,antimicrobial,cytotoxic and analgesic activities of ethanolic extract of Mentha arrensis l.,in different in vivo and in vitro experimental models.Methods:In vitro DPPH radical scavenging assay was used to evaluate the antioxidant activity of the plant extract.In vivo analgesic activity was carried out by acetic acid—induced writhing test in Swiss albino mice.All studies in mice were undertaken at the doses of 250 and 500 mg/kg body weight.Antibacterial activilv was studied by disk diffusion assay against some Gram—positive and Gram—negative bacterial strains.Brine shrimp lethality assay was used to investigate cyloloxicity effects of the plant extract.Results:The extract showed free radical scavenging activity in the DPPH assay(IC5041 μg/mL)compared to the standard antioxidant ascorbic acid(IC5019 μg/mL).The extract also produced prominent antimicrobial activity against Salmonella typhi.Salmonella paratyphi.Shigella boydii,Streptococcus pyogenes and Streptococcus aureus compared to standard drug kanamycin at the dose of 30 μg/disc.The extract exhibited lethality against the brine shrimp nauplii with the LC50,values of 40 μg/mL.and also 90%mortality(LC90) value was found to be 160 μg/mL.In analgesic test.the extract demonstrated statistically significant（P【0.01） analgesic effect in acetic acid induced writhing in white albino mice al both dose levels.Conclusions:These results suggest that the ethanolic extract of Mentha arvenns L.has potential antioxidant,antibacterial,cytotoxic and analgesic activities that support the ethnopharmacological uses of this plant.

Effects of Ropivacaine-sufentanil Epidural Analgesia on Labor and Maternal and Neonatal Outcomes

[Objectives]This study aimed to investigate the effects of ropivacaine-sufentanil epidural analgesia on labor and maternal and neonatal outcomes.[Methods]A total of 180 primiparas in full-term pregnancy were selected.They were randomly divided into treatment group(n=90)and control group(n=90).The primiparas in the treatment group were injected epidurally with ropivacaine and sufentanil for analgesia,and the primiparas in the control group were subjected to vaginal delivery.The VAS scores at 5,10,30 and 60 min of analgesia were observed.The vaginal bleeding amount,total labor duration,neonatal Apgar score and vaginal delivery rate of the two groups were compared.[Results]Compared with the control group,the VAS score in the treatment group differed insignificantly after 5 min of analgesia(P>0.05),and decreased significantly after 10,30 and 60 min of analgesia(P<0.05).The vaginal bleeding amount of the treatment group was significantly smaller than that of the control group(P<0.05).There was no significant difference in the neonatal Apgar score between the two groups(P>0.05).In the treatment group,the vaginal delivery rate increased(P<0.05),the second stage of labor was prolonged(P<0.05),and the first and third stages of labor did not change significantly(P>0.05).[Conclusions]Epidural analgesia with ropivacaine and sufentanil has a good analgesic effect and good safety,and is worthy of clinical promotion.

Antipyretic,anti-inflammatory and analgesic properties of nilavembu kudineer choornam:a classical preparation used in the treatment of chikungunya fever

Objective:To investigate the efficacy of ethanolic extract of nilavembu kudineer choornam (EENKC) in inflammation,pain and fever using animal models to support its actions.Methods: Acute toxicity study of EENKC was performed in mice to fix the effective dose.The antipyretic, anti-inflammatory and analgesic activity of EENKC was evaluated in brewer’s yeast induced pyrexia in rats,carrageenan-induced inflammation in rats and acetic-acid induced writhing in mice model.Results:Acute toxicity revealed that EENKC didn’t show death and toxic signs up to 2 000 mg/kg.In brewer’s yeast induced pyrexia and carrageenan-induced inflammation EENKC at the doses of 200 and 400 mg/kg inhibited fever and inflammation significantly(P【0.01 and【0.05) compared to control animals.In mice,the number of writhing induced by acetic-acid was significantly(P【0.01) reduced after treatment with both the dose of EENKC than control animals. EENKC 200 mg/kg inhibits inflammation higher level in carrageenan-induced paw edema,but there is no significant difference when compared to indomethacin 10 mg/kg.Conclusions:The present findings revealed that EENKC possesses antipyretic,anti-inflammatory and analgesic activity which supports nilavembu kudineer choornam efficacy in chikungunya fever.

Anti-inflammatory and analgesic activities of Melanthera scandens

Objective:To evaluate the anti-inflammatory and analgesic activities of leaf extract of Melanthera scandens(M.scandens).Methods:The crude leaf extract(39-111 mg/kg)of M.scandens was investigated for anti-inflammatory and analgesic activities using various experimental models.The anti-inflammatory activity was investigated using carragenin,egg-albumin induced oedema models,while acetic acid,formalin-induced paw licking and thermal-induced pain models were used to evaluate the antinociceptive property.Results:The extract caused a significant(P<0.05-0.001)dose-dependent reduction of inflammation and pains induced by different agents used.Conclusions:The leaf extract possesses anti-inflammatory and analgesic effects which may be mediated through the phytochemical constituents of the plant.