Individual Factors Modifying Postoperative Pain Management in Elective Total Hip and Total Knee Replacement Surgery.

Total hip and knee replacements are the most common orthopedic procedures performed due to osteoarthritis. Pain is an intrinsic symptom accompanying osteoarthritis, persisting long before surgery, and continuing during the preoperative and postoperative periods. Appropriate pain management after surgery determines the comfort, duration, and cost of hospitalization, as well as the effectiveness of postoperative rehabilitation. Individual differences in pain perception and tolerance in orthopedic patients remain an important research topic. Therefore, the aim of this study was to investigate the predictors of analgesic requirements (morphine, acetaminophen, and ketoprofen), including individual pain threshold and tolerance, body mass index (BMI), diabetes, and beliefs about pain control in patients undergoing elective hip or knee arthroplasty using a multilevel regression model (N = 147, 85 women, 62 men, 107 after hip replacement, and 40 after knee replacement). Results: Higher pain tolerance was associated with a lower dose of morphine per kg after surgery. Patients undergoing hip surgery received a lower dose of ketoprofen than patients undergoing knee surgery. The more the patient believed in personal pain control, the stronger the negative relationship between pain tolerance and morphine requirement. The lowest doses were given to patients with the highest pain tolerance and the greatest belief in personal control. Factors such as belief in pain control and pain tolerance should be considered in comprehensive postoperative pain management in orthopedic patients to reduce opioid doses and, thus, side effects.

Level of Disability after Total Hip Replacement in Patients with Some COMT Gene Polymorphism.

BACKGROUND: The COMT gene encodes the enzyme catechol-O-methyltransferase, which is a key modulator of dopaminergic and adrenergic neurotransmission. Hip osteoarthritis is accompanied by reduced mobility and some level of disability. In our study, we analyzed the association between some COMT gene polymorphisms and reduced mobility in patients after total hip replacement (THR). METHODS: The operative procedures were performed on 195 patients with symptomatic and radiologically advanced hip osteoarthritis. In the postoperative follow-up, we assessed hip function with the Harris Hip Score (HHS) and the degree of disability with the Oswestry Disability Index (ODI). These procedures were repeated three times at defined intervals (one week, six weeks, and six months) after the total hip replacement. Genomic DNA was extracted from peripheral blood. SNPs in the COMT genes rs4680:A>G, rs6269:A>G, rs4633:C>T, and rs4818:C>G were genotyped. RESULTS: Our findings suggest an association between COMT gene variability and the level of disability measured by the Oswestry Disability Index (ODI) in patients after total hip replacement (THR). CONCLUSIONS: A higher number of COMT G alleles (rs4818) is an independent factor in a significant reduction in disability degree at both one week and six months after total hip replacement (THR), regardless of age or gender.

Significance of Selected Environmental and Biological Factors on the Risk of FASD in Women Who Drink Alcohol during Pregnancy.

Prenatal alcohol exposure (PAE), which refers to alcohol consumption by pregnant women, is associated with the risk of numerous severe complications during fetal development. The State Agency for Alcohol Problem Solving reports that the incidence of fetal alcohol spectrum disorder (FASD) in Poland's general population is over 1.7%, and the incidence of fetal alcohol syndrome (FAS) is estimated at more than 0.5%. This study aimed to evaluate the significance of alcohol exposure and focused on the pattern of alcohol intoxication exhibited by the mother during pregnancy and other environmental factors of the maternal environment contributing to the development of FASD. The study covered 554 subjects, including 251 mothers and 303 children (213 girls and 90 boys). The mother's drinking problem was determined based on the information obtained from the case history. All children qualified for the study fulfilled the h-PAE (high alcohol exposure) criteria during their fetal life. The clinical diagnosis of FAS and pFAS (occurrence of morphological symptoms of fetal alcohol syndrome) was made using a four-digit diagnostic questionnaire validated in the Polish version of the Washington Questionnaire for the assessment of the spectrum of alcohol-related neurodevelopmental disorders or alcohol-related cognitive impairment (ARND/C). Statistical analysis of the obtained research results was developed using statistical software-STATISTICA PL, version 13.1 (StatSoft, Inc., Szczecin, Poland 2016, STATISTICA-data analysis software system, version 13.1). The most destructive drinking behaviors are compulsive intoxication (BD, binge drinking) during the first 6 weeks of pregnancy and chronic addiction throughout its duration (CHD, chronic drinking). Chronic alcohol intoxication (CHD) leads to a poorer nutritional status in mothers, which is reflected in a lower body mass index (BMI) (<18 kg/m2).

Evaluation of the in vitro permeation parameters of topical ketoprofen and lidocaine hydrochloride from transdermal Pentravan® products through human skin.

In the treatment of pain, especially chronic pain, the rule of multimodal therapy applies, based on various painkillers mechanisms of action. The aim of the conducted study was to evaluate the in vitro penetration of ketoprofen (KET) and lidocaine hydrochloride (LH) through the human skin from a vehicle with transdermal properties. The results obtained with the use of the Franz chamber showed statistically significantly higher penetration of KET from the transdermal vehicle as compared to commercial preparations. It was also shown that the addition of LH to the transdermal vehicle did not change the amount of KET permeated. The study also compared the penetration of KET and LH by adding various excipients to the transdermal vehicle. Comparing the cumulative mass of KET that penetrated after the 24-h study, it was observed that the significantly highest permeation was found for the vehicle containing additionally Tinctura capsici, then for that containing camphor and ethanol, and the vehicle containing menthol and ethanol as compared to that containing Pentravan® alone. A similar tendency was observed in the case of LH, where the addition of Tinctura capsici, menthol and camphor led to a statistically significant higher penetration. Adding certain drugs such as KET and LH to Pentravan®, and substances such as menthol, camphor or capsaicin, can be an interesting alternative to administered enteral drugs especially in the group of patients with multiple diseases and polypragmasy.

Distribution of Elements in Beaver (Castor fiber) Tooth Enamel as a Sign of Environmental Adaptation: the Special Role of Fe, Co, Mg, and Fluorides (F-).

The aim of the study was to investigate the distribution of elements (Ca, Mg, Fe, P, Zn, Na, K, Cu, Cr, Mo, Co, Se) analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES) and fluorides (F-) determined potentiometrically using an ion-selective electrode in the enamel of European beaver (Castor fiber) teeth. Material for the study was tooth enamel collected from lower jaws from the skulls of the animals borrowed from museum collections (animals inhabited north-western Poland). The results of our study indicate the important role of F- as an element that can affect the hardness and strength of beaver tooth enamel. Critical to the function of beaver teeth (i.e., shearing and crushing wood) is the presence of elements such as Fe in the central incisor labial aspect (orange layer of the incisor enamel), Mg in the inner side of the incisor enamel, and Co and F- in the enamel of the molars. Thanks to the high content of these elements, the enamel is durable and the teeth are adapted to the nutritional and ecological characteristics of this mammalian species. Our study on the distribution of elements in the enamel of beaver teeth may also be important for the understanding of the enamel mineralization processes, determining how elements change the properties of the materials, and exploring the relationship between the environment and life history of the beaver.

Lack of Association between (AAT)n Polymorphism of the CNR1 Gene Encoding the Cannabinoid Receptor (CB1) and Patient's Quality of Life.

Genetic factors may predispose persons to decreased pain excitability. One of the interesting modulators affecting pain perception may be polymorphisms of the cannabinoid receptor type 1 (CNR1) gene. In this study, we examined the association between three-nucleotide repeats (AAT) polymorphism located in the 3'UTR non-translational region of CNR1 and the patient's quality of life after total hip arthroplasty. Our study examined the degree of pain sensation, hip function, and the patient's performance at defined intervals after elective hip replacement due to degenerative changes. The study included 198 patients (128 women and 70 men). The average age was 67 years. PCR genotyping assay was used to identify the (AAT)n triplet repeat polymorphism in the CNR1 gene. The (AAT)n repeat number was determined by sequencing using a standard sequencing protocol. Our study found no statistically significant association between the degree of pain, hip function, and the change in the degree of disability and the (AAT)n polymorphism in the CNR1 gene, no statistically significant correlations between clinical symptoms, the patient's age, and the number of AAT repeats, no association between the length of the allele and the degree of pain, hip function, and the change in disability.

No Association between Genetic Variants of the COMT and OPRM1 Genes and Pain Perception among Patients Undergoing Total Hip or Knee Arthroplasty for Primary Osteoarthritis.

Each year approximately 1 million total hip replacements are performed worldwide. The most common indications to choose this procedure are rest pain and pain after activity as well as functional limitations influencing daily activities. Experimental pain is highly variable by individuals, which is partly due to genetics. The aim of the study was to investigate a possible association of the catechol-O-methyltransferase (COMT) and µ-opioid receptor (OPRM1) genotypes with pain perception in patients undergoing total hip replacement and total knee replacement taking into account aspects such as age, sex and diabetes. The study included 207 patients (119 females, 88 males, median age 65 years, range 33−77) that qualified for surgical treatment (total hip replacement and knee arthroplasty) due to osteoarthritis. Pain sensitivity measurement was performed using a standard algometer. The genomic DNA was extracted from the buccal cells.. Single locus analysis was conducted using a general linear model. In the study group, we did not find statistically significant genetic associations between variants of COMT and OPRM1 and pain thresholds/pain tolerance. The analysis of subjective pain perception using the visual analog scale did not show any relationship between the OPRM1 rs1799971A>G variant and COMT rs4680, rs4633, rs4818 and rs6269.

Is Physical Activity an Effective Factor for Modulating Pressure Pain Threshold and Pain Tolerance after Cardiovascular Incidents?

The purpose of this study was to investigate whether regular physical activity can alter the pressure pain threshold, pain tolerance, and subjective pain perception in individuals who have experienced a cardiovascular event. The study involved 85 individuals aged 37 to 84 years (M = 65.36) who qualified for outpatient cardiac rehabilitation, which consisted of 24 physical training sessions. The patients were all tested twice: on the first and last day of the outpatient cardiac rehabilitation program. Assessments of the pressure pain threshold and pain tolerance were performed with an algometer. To assess the pain coping strategies, the Pain Coping Strategies Questionnaire (CSQ) and parenting styles were measured retrospectively with subjective survey questions. The main results of the study showed that patients achieved significantly higher pressure pain thresholds after a physical training cycle (ps < 0.05, η2 = 0.05-0.14), but found no differences in the pain tolerance (ps > 0.05). A lower preference for the better pain coping strategy explanation (ß = -0.42, p = 0.013) and growing up in a family with a less neglectful atmosphere (ß = -0.35, p = 0.008) were associated with increased pressure pain threshold after physical training. The results suggest that physical activity is an important factor in modulating the pressure pain threshold.

Influence of COMT (rs4680) and DRD2 (rs1076560, rs1800497) Gene Polymorphisms on Safety and Efficacy of Methylphenidate Treatment in Children with Fetal Alcohol Spectrum Disorders.

Fetal alcohol spectrum disorders (FASD) in a course of high prenatal alcohol exposure (hPAE) are among the most common causes of developmental disorders. The main reason for pharmacological treatment of FASD children is attention deficit hyperactivity disorder (ADHD), and methylphenidate (MPH) is the drug of choice. The aim of the study was to assess whether children born of hPAE with ADHD, with or without morphological FASD, differ in terms of catechol-O-methyltransferase (COMT) and dopamine receptor D2 (DRD2) gene polymorphisms, and if genetic predisposition affects response and safety of MPH treatment. The polymorphisms of COMT (rs4680) and DRD2 (rs1076560, rs1800497) were analyzed in DNA samples. A borderline significance was found for the correlation between MPH side effects and the G allele of COMT (rs4680) (p = 0.04994) in all ADHD children. No effect of COMT (rs4680) and DRD2 (rs1076560, rs1800497) polymorphisms and the treatment efficacy was observed. The analyzed DRD2 and COMT gene polymorphisms seem to play no role in MPH efficacy in ADHD children with hPAE, while low-activity COMT (Met158) variant carriers may be more intolerant to MPH. The MPH treatment is effective in ADHD independent of FASD, although the ADHD-FASD variant requires higher doses to be successful. These results may help in optimization and individualization in child psychiatry.

Cannabis and cannabinoids: pharmacology and therapeutic potential.

INTRODUCTION: Cannabis (also known as marijuana) is the most frequently used psychoactive substance in the world. The role of cannabis in medicine is rapidly evolving, and advances in the understanding of its pharmacology have led to numerous proposed uses of these drugs. STATE OF THE ART: Cannabis contains Δ9-tetrahydrocannabinol and cannabidiol as the primary constituents responsible for pharmacological activity. It is now known that there are at least two types of cannabinoid receptors. CB1 receptors are found mainly in the CNS, and their primary role is to inhibit the release of neurotransmitters. CB2 receptors' leading role is to modulate cytokine release and immune cell migration. Colocalisation of cannabinoid receptors with other types of nervous system receptors allows them to interact with many other transmitters such as dopamine, noradrenaline, acetylcholine, gamma-aminobutyric acid, serotonin, and glutamic and aspartic acids. CLINICAL IMPLICATIONS: The rapidly expanding understanding regarding cannabinoids led to initial attempts to treat selected diseases with cannabinoid receptor agonists and antagonists. The most promising of these was the potential possibility of treating diseases for which current therapy is unsatisfactory, such as neurological diseases including multiple sclerosis, spastic muscular tension, extrapyramidal system diseases, neurodegenerative diseases and cerebral ischaemia. Attempts to treat psychiatric diseases (e.g. psychoses, neuroses, mood disorders, and alcohol dependence syndrome) with cannabinoids are much less advanced. FUTURE DIRECTIONS: Cannabis and cannabinoids can be widely used to treat several diseases or alleviate symptoms, but their efficacy for specific indications is not always apparent. Further exploration is needed to understand whether the enhanced sensitivity to the cognitive effects of Δ9-THC depends on brain cannabinoid receptor dysfunction, and how these changes contribute to the cognitive deterioration and core pathophysiology symptoms associated with schizophrenia or other neurological and somatoform disorders.

Interactions between Gene Variants within the COL1A1 and COL5A1 Genes and Musculoskeletal Injuries in Physically Active Caucasian.

The COL1A1 and COL5A1 variants have been associated with the risk of musculoskeletal injuries. Therefore, the main aim of the study was to investigate the association between three polymorphisms within two genes (rs1800012 in COL1A1, as well as rs12722 and rs13946 in COL5A1) and the reported, yet rarely described in the literature, injuries of the joint and muscle area in a physically active Caucasian population. Polish students (n = 114) were recruited and divided into the following two groups: students with (n = 53) and without (n = 61) injures. Genotyping was carried out using real-time PCR. The results obtained revealed a statistically significant association between rs1800012 COL1A1 and injury under an overdominant model. Specifically, when adjusted for age and sex, the GT heterozygotes had a 2.2 times higher chance of being injured compared with both homozygotes (TT and GG, 95% CI 0.59-5.07, p = 0.040). However, no significant interaction between the COL5A1 variants, either individually or in haplotype combination, and susceptibility to injury were found. In addition, the gene-gene interaction analysis did not reveal important relationships with the musculoskeletal injury status. It was demonstrated that rs1800012 COL1A1 may be positively associated with physical activity-related injuries in a Caucasian population. Harboring the specific GT genotype may be linked to a higher risk of being injured.

Kidney damage from nonsteroidal anti-inflammatory drugs-Myth or truth? Review of selected literature.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely available drugs with anti-inflammatory and analgesic properties. Their mechanism of action is associated with the enzymes of the arachidonic acid cycle (cyclooxygenases: COX-1 and COX-2). The cyclooxygenase pathway results in the formation of prostanoids (prostaglandins [PGs], prostacyclins, and thromboxanes). It affects various structures of the human body, including the kidneys. Medical literature associates the usage of NSAIDs with acute kidney injury (AKI), tubulointerstitial nephritis (TIN), as well as nephrotic syndrome and chronic kidney disease (CKD). AKI associated with the chronic consumption of NSAIDs is mainly attributed to pharmacological polytherapy and the presence of cardiovascular or hepatic comorbidities. The pathomechanism of AKI and CKD is associated with inhibition of the biosynthesis of prostanoids involved in the maintenance of renal blood flow, especially PGE2 and PGI2. It is suggested that both COX isoforms play opposing roles in renal function, with natriuresis increased by COX-1 inhibition followed by a drop in a blood pressure, whereas COX-2 inhibition increases blood pressure and promotes sodium retention. TIN after NSAID use is potentially associated with glomerular basement membrane damage, reduction in pore size, and podocyte density. Therefore, nephrotic proteinuria and impairment of renal function may occur. The following article analyzes the association of NSAIDs with kidney disease based on available medical literature.

Epidemiology of Anthropometric Factors in Glioblastoma Multiforme-Literature Review.

Although glioblastoma multiforme (GBM) is a widely researched cancer of the central nervous system, we still do not know its full pathophysiological mechanism and we still lack effective treatment methods as the current combination of surgery, radiotherapy, and chemotherapy does not bring about satisfactory results. The median survival time for GBM patients is only about 15 months. In this paper, we present the epidemiology of central nervous system (CNS) tumors and review the epidemiological data on GBM regarding gender, age, weight, height, and tumor location. The data indicate the possible influence of some anthropometric factors on the occurrence of GBM, especially in those who are male, elderly, overweight, and/or are taller. However, this review of single and small-size epidemiological studies should not be treated as definitive due to differences in the survey methods used. Detailed epidemiological registers could help identify the main at-risk groups which could then be used as homogenous study groups in research worldwide. Such research, with less distortion from various factors, could help identify the pathomechanisms that lead to the development of GBM.

Association of COMT gene variability with pain intensity in patients after total hip replacement.

Pain is one of the most interdisciplinary clinical symptoms of a disease. The aim of the study was to evaluate the association of COMT gene polymorphism with pain perception in patients after total hip replacement (THR). The study included 195 patients qualified for surgical treatment (THR) due to osteoarthritis. Patients previously undergoing hip replacement subsequently underwent multimodal pain management therapy, in accordance with the recommendations for treating postoperative pain. The intensity of pain was measured three times at pre-defined time intervals: 1.5, 6 and 12 months after hip replacement, using the visual analogue scale. Single nucleotide polymorphism (SNP) in the COMT gene rs4680: A>G (Val158Met), rs6269: A>G (promoter region), rs4633: C>T (His62His) and rs4818: C>G (Leu136Leu) was genotyped. COMT SNP frequency distribution was analysed. For rs6269 and rs4818, the minor allele was the G allele (38.7 and 38.5%, respectively). It was also observed that rs4633 (T) allele frequency (50%) equalled that of the rs4680 (A) allele (50%). We assessed COMT haplotype frequency in the patients studied. The most frequent haplotype was haplotype M (ATCA) (50%), the rarest haplotype was haplotype R (ATGG), with a frequency of 0.3%. The most frequent diplotype was H/M, which was found in 37.95% of the patients. The frequency of other diplotypes was: M/M-24.10%, H/H-15.90% and L/M-13.33%. The study showed a significant association of rs4818 G allele and equivalent COMT H haplotype with lower sensitivity to pain after hip replacement.

Common Missense Variant of SCN9A Gene Is Associated with Pain Intensity in Patients with Chronic Pain from Disc Herniation.

Objective: Lumbar intervertebral disk herniation (LDH) is considered one of the major risk factors for lower back pain, mainly caused by irritation of a spinal nerve or its root. One of the genes related to pain perception is SCN9A, which encodes the voltage gated sodium channel NaV1.7, a key molecule involved in peripheral pain processing. It had been presented before that a common polymorphism within SCN9A (rs6746030: G > A, R1150W) might influence nociception in the general population. Hence, the present study was aimed at investigating the association between SCN9A polymorphism and pain sensitivity. Methods: Pain intensity was measured by means of the visual analog pain scale (VAS) in 176 Caucasian patients with a history of leg and back pain who had been diagnosed with LDH and underwent lumbar discectomy. SCN9A polymorphism was determined by means of TaqMan assay. Results: A significantly higher preoperative back pain intensity was observed among rs6746030 A minor allele carriers, compared with GG homozygotes (VAS = 7.5 ± 2.4 vs 6.5 ± 2.7, P = 0.012). Similarly, A allele carriers were characterized by higher values of leg pain prior to surgery (VAS = 7.8 ± 2.3 vs 6.8 ± 2.6, P = 0.013). However, postoperative improvement in pain reduction was similar in both groups. Conclusions: Our results suggest that the SCN9A rs6746030 polymorphism may be associated with pain intensity in patients suffering from symptomatic disc herniation.

IL17A and IL17F Gene Polymorphism Association with Psoriasis Risk and Response to Treatment in a Polish Population.

BACKGROUND: Recent studies have revealed the pivotal role of Th17 cells and interleukin-17 (IL-17) in plaque psoriasis development and treatment outcome. The IL-17 family consists of 6 structurally related cytokines (IL-17A, IL-17B, IL-17C, IL-17D, IL-17E, IL-17F), of which IL-17A and IL-17F mediate similar biological effects. OBJECTIVES: The aim of this study was to evaluate an association between the IL17A (-197G>A; rs2275913) and IL17F (rs763780: T>C; rs11465553: G>A; rs2397084: T>C) polymorphisms with psoriasis susceptibility as well as response to topical and combined topical with narrow-band ultraviolet B (NB-UVB) therapy in a Polish population. METHODS: Association study involving 407 psoriasis patients and 205 healthy controls. Treatment efficacy was analyzed in 207 patients with mild psoriasis (Psoriasis Area and Severity Index; PASI 3-12) and moderate psoriasis (PASI 12-18), who were randomly subjected to topical or combined topical and NB-UVB treatment. The polymorphisms were evaluated by RT-PCR. RESULTS: No statistically significant differences between psoriasis patients and controls were found in the frequency of the evaluated IL17A and IL17F genotypes and haplotypes. The IL17A or IL17F polymorphisms were not associated with treatment outcome measures: efficacy of treatment at the eighth week of the study and PASI change after topical or combined topical and NB-UVB therapy. However, IL17F rs2397084 variant allele C carriers required a significantly higher number of NB-UVB irradiations in comparison to TT homozygotes (15.5 ± 11.4 vs. 11.1 ± 11.9, p = 0.047) to produce a positive clinical response. CONCLUSION: It can be stated that the IL17A and IL17F polymorphisms are not markers of susceptibility to psoriasis. However, the IL17F polymorphism may affect the response to NB-UVB therapy.

Effect of interleukin 6 -174G>C gene polymorphism on opioid requirements after total hip replacement.

OBJECTIVE: In recent years, increasing attention has been paid to the contribution of genetic factors to variability in patient pain threshold and the efficacy of pain management. One of the genes implicated in pain pathology and treatment response is interleukin 6 (IL6). The aim of the present study was to evaluate the association between IL6 (rs1800795: -174G>C) and opioid requirements in patients after total hip replacement (THR). METHODS: A total of 196 patients eligible for the study (126 women, 70 men) were subjected to THR. The THR procedure was performed using spinal anaesthesia after implementing routine peri-operative monitoring. After the procedure each patient was individually observed, and the patient-specific chart of dynamic changes in pain perception was recorded, using the five-level Verbal Rating Scale (VRS). The multimodal analgesic treatment after THR was defined by the operating surgeons after considering indications and contraindications to the use of different groups of drugs (opioid and non-opioid analgesics). Postoperative pain was controlled by the patient-controlled analgesia method and VRS during the day-time, as well as night-time nurse-controlled analgesia. All medication adjustments were recorded in the individual patient files. In the case of moderate pain intensity (VRS-assessed), a patient was administered the non-opioid analgesic drug, and for high intensity pain the opioid. The analysis of pain relief therapy included information on the drugs applied, mode of dosing (single or multiple), daily dose, route of administration, and drug refusal due to the absence of pain recorded each study day, i.e. on the day of surgery and recovery in the postoperative room (day 0), and then daily from day 1 to day 6. Polymorphism rs1800795:G>C in the promoter region of the IL6 gene (-174G>C) was determined using the PCR-RFLP method. RESULTS: The patients carrying at least one IL6 -174G allele (GG homozygote and GC heterozygote) were administered opioids significantly more often on days 0 (p = 0.0029), 3 (p = 0.019) and 4 (p = 0.031) after surgery compared with CC homozygous patients. Those patients also required a significantly higher opioid dose on days 3 (p = 0.029) and 4 (p = 0.030). Multivariate analysis demonstrated that the presence of the -174G allele was an independent factor predisposing patients to the administration of opioids during the first 24 h [p = 0.001, odds ratio (OR) 7.1, 95 % confidence interval (CI) 2.17-22.7], on day 3 (p = 0.01, OR 2.79, 95 % CI 1.25-6.26) and day 4 (p = 0.01, OR = 2.61, 95 % CI 1.17-5.79). CONCLUSION: The presence of the G allele IL6 gene (-174G>C) polymorphism was found to be an independent factor predisposing to a higher dose and more frequent administration of opioids in the first days after total hip replacement.

Effects of perinatal exposure to lead (Pb) on purine receptor expression in the brain and gliosis in rats tolerant to morphine analgesia.

The aim of the present study was to investigate the molecular effects of perinatal exposure to lead (Pb) on protein and mRNA expression of purine receptors: P2X4, P2X7, adenosine receptor A1; and astrocytes (GFAP mRNA expression) and on microglia activation (Iba1 mRNA expression) in several structures of the mesolimbic system (striatum, hippocampus, prefrontal cortex) in rats expressing tolerance to the antinociceptive effect of morphine. Rat mothers were orally treated with 0.1% lead acetate from conception, through gestation, and postnatally, as well as to offspring up to day (PND) 28; subsequently molecular studies were conducted on adult (PND 60) male rats. Morphine tolerance developed more strongly in rats perinatally exposed to Pb. The analysis revealed a significant up-regulation of protein and mRNA P2X4 receptor expression in the striatum and prefrontal cortex but not in the hippocampus; P2X7 protein and mRNA receptor expression in the striatum and hippocampus, but not in the prefrontal cortex; A1 protein receptor expression in all investigated structures and A1 mRNA expression in the striatum and hippocampus; Iba1 mRNA expression in the striatum and hippocampus; and GFAP mRNA expression in the striatum and prefrontal cortex. Immunohistochemical analysis has also revealed significant alterations. Strong expressions of P2X4, P2X7, A1 receptors, astrocytes and microglia activation were observed in the hippocampus in Pb and/or morphine treated rats. The higher expression of purine receptors and glial cell activation are important markers of neuroinflammatory processes. Therefore, we conclude that Pb-induced neuroinflammation may be responsible for the intensification of morphine tolerance in the Pb-treated rats. Additionally, the dysregulation of A1 adenosine receptors, mainly in the hippocampus, may also be involved in the intensification of morphine tolerance in Pb-treated rats. Our study demonstrates the significant participation of environmental factors in addictive process; additionally, it shows the necessity of modification of addictive disorder with neuroprotective agents.

Influence of variation in the catechol-O-methyltransferase gene on the clinical outcome after lumbar spine surgery for one-level symptomatic disc disease: a report on 176 cases.

BACKGROUND: This study was aimed at the evaluation of the relationship between genetic polymorphisms of catechol-O-methyltransferase (COMT) (rs4680:A > G-Val158Met, rs6269:A > G, rs4633:C > T, rs4818:C > G) and pain sensitivity after lumbar discectomy. METHODS: All patients had one-level symptomatic disc herniation from L3 to S1. The primary data recorded included visual analogue pain scales assessing back and leg pain, Oswestry Disability Questionnaire assessing quality of life and pain intensity, received/filled pre- and postoperatively. Each subject was genotyped for single-nucleotide polymorphism in the COMT gene. Clinical outcome was measured by difference between pre- and postoperative values and those results were analyzed with genetics findings. RESULTS: Pain intensity was associated with the COMT polymorphism. Carriers of rs6269 AA, rs4633 TT, rs4818 CC, and rs4680 AA genotypes were characterized by the lowest preoperative scores related to pain intensity and lower pain intensity at 1 year after the surgery. The rs4633 CC, rs4680 GG genotypes demonstrated significant clinical improvement in VASBACK score at 1 year after the surgery. Patients with COMT haplotype associated with low metabolic activity of enzyme (A_C_C_G) showed better clinical outcome measured by ODI score and VASBACK score 1 year after surgery. We did not observe any significant correlation between leg pain and single-nucleotide polymorphisms in the COMT gene. CONCLUSIONS: The results of our study indicate that polymorphism in the COMT gene may play an important role in the mechanism of pain perception, which may have a potential implication for clinical decision-making in the future.

Thymidylate synthase gene polymorphism and survival of colorectal cancer patients receiving adjuvant 5-fluorouracil.

Limited studies indicate a possible association of 5'-UTR thymidylate synthase enhancer region polymorphism and treatment outcome in patients medicated with 5-fluorouracil (5-FU). The study was designed to verify the relationship in patients with colorectal cancer (CRC), a Polish population that received 5-FU-based adjuvant chemotherapy. The study analyzed 145 Astler-Coller B2 and C CRC patients. Genotyping for a variable number of tandem repeats and G to C single-nucleotide polymorphism in the 5'-UTR of the thymidylate synthase (TS) gene was carried out. TS genotypes were classified into high expression (high TS) and low expression types (low TS). High TS was found in 22.8% of patients. The right-side tumors were more frequently associated with high TS than the left-side tumors (p=0.024). High TS was only found in 9.3% of rectal tumors, but in 29.7% of colon cancers (p=0.0042). Disease-free survival after 20 months (DFS 20) was longer in subjects with low TS than in high TS (p=0.043). Patients who underwent chemotherapy had longer DFS 20 in the low TS than in the high TS subgroup (p=0.051). The low TS was found to be an independent good prognostic factor for DFS 20 in the whole group as well as in the subgroup treated with chemotherapy (p=0.024 and p=0.034, respectively). Patients with low TS did not show any differences in DFS 20 whether they were treated with adjuvant chemotherapy or not. Proximal CRC tumors are characterized by higher TS expression genotypes than distal tumors, and are at significantly greater risk of early recurrence during the first 20 months after surgery.