Pain medicine: general view to the problem

The explosive growth of our knowledge of every aspect of pain in recent years has produced major advances in the classification and management of the varieties of pain. However, despite of advancing knowledge in the field of pain medicine for last decades, the burden of pain remains unacceptably high. Epidemiological studies point to the high prevalence of chronic pain across the world associated with staggering socioeconomic costs. Unfortunately, existing therapies fail to offer good pain relief to the majority of these patients. There have been some modest advances with the approval of some new therapies, but nevertheless pain medicine is still waiting to find out new initiatives and approaches that serve to a better understanding of pain mechanisms leading to effective therapies

Tolerance to Non-Opioid Analgesics is Opioid Sensitive in the Nucleus Raphe Magnus

Repeated injection of opioid analgesics can lead to a progressive loss of effect. This phenomenon is known as tolerance. Several lines of investigations have shown that systemic, intraperitoneal administration or the microinjection of non-opioid analgesics, non-steroidal anti-inflammatory drugs (NSAIDs) into the midbrain periaqueductal gray matter induces antinociception with some effects of tolerance. Our recent study has revealed that microinjection of three drugs analgin, ketorolac, and xefocam into the central nucleus of amygdala produce tolerance to them and cross-tolerance to morphine. Here we report that repeated administrations of these NSAIDs into the nucleus raphe magnus (NRM) in the following 4 days result in progressively less antinociception compare to the saline control, i.e., tolerance develops to these drugs in male rats. Special control experiments showed that post-treatment with the μ-opioid antagonist naloxone into the NRM significantly decreased antinociceptive effects of NSAIDs on the first day of testing in the tail-flick (TF) reflex and hot plate (HP) latency tests. On the second day, naloxone generally had trend effects in both TF and HP tests and impeded the development of tolerance to the antinociceptive effect of non-opioid analgesics. These findings strongly support the suggestion of endogenous opioid involvement in NSAIDs antinociception and tolerance in the descending pain-control system. Moreover, repeated injections of NSAIDs progressively lead to tolerance to them, cross-tolerance to morphine, and the risk of a withdrawal syndrome. Therefore, these results are important for human medicine too

Effect of Adjuvant (Hormonal) Therapy on Bone Mineral Density in Caucasian Women with Breast Cancer

Background and Aim: Aromatase inhibitors (AIs) and selective estrogen receptor modulators (SERMs) are important components of adjuvant endocrine therapy in postmenopausal women with estrogen receptor positive breast cancer. The aim of our study was to assess the effect of AIs and SERMs on bone mineral density (BMD) in Caucasian postmenopausal women with breast cancer. Patients and Methods: 118 postmenopausal Caucasian women were enrolled in the study. 60 patients were receiving AIs and 58 patients – SERMs-Tamoxifen. Patients were also divided into two sub groups: 1) patients with more than 3 years of last menstrual period (LMP) and 2) patients with less than 3 years of last menstrual period. Results: Among Aromatase inhibitors treated patients, there was a decrease in median BMD from baseline to 5 years in lumbar spine and total hip compared with the Tamoxifen group. No patients with normal BMD at baseline became osteoporotic at 5 years. Conclusion: Aromatase inhibitors are associated with accelerated bone loss over the 5-year treatment period. In postmenopausal women, treatment with tamoxifen is associated with preservation of the bone mineral density of the lumbar spine

The impact of female obesity on the outcome of fertility treatment

Peer reviewedPublisher PD

Thermal and mechanical sensory and pain testing in healthy students

Several lines of clinical and experimental investigations of a wide variety of painful conditions have suggested ethnic and gender differences in pain perception. In this study we report some findings of cold and heat sensations, thermal pain thresholds, mechanical pressure thresholds and pressure pain thresholds in healthy student volunteers. We did not find any statistical significant differences in thermal assessment. However, we revealed gender differences on the mechanical pressure sensation threshold and the mechanical pressure pain threshold. Our study confirmed significant variability across trials and individuals, which appeared greater at lower heat and mechanical pressure intensities. Additional studies and collecting more data are needed to determine ethnic and gender differences between groups

The effects of short-term energy restriction in overweight/obese females on reproductive outcomes.

In the general population, one in five couples experiences difficulty in conceiving a child. The role of obesity on women’s fecundity has become a focus of attention in recent years. Successful treatment of infertility through Assisted Reproductive Technology (ART) is also compromised by the presence of obesity, which occurs in 30 % of women seeking treatment. A negative correlation exists between increased body mass index (BMI) and the number of collected oocytes and a lower birth rate after ART. Furthermore, a number of studies have established that weight loss improves natural conception rates in overweight women. Whether weight management can improve success rates in overweight / obese women undergoing in vitro fertilisation (IVF) has not been studied. The purpose of this project was to explore the role of short–term weight loss on potential pregnancy outcomes in overweight / obese women undergoing IVF programme. However, to establish this relationship, we proposed to carry out two studies to assess the following: (I) The feasibility of very low calorie diet (VLCD) during IVF treatment with respect to duration, level of restriction and tolerability of the diet during hormonal down regulation in women (Chapter 2). (II) How energy restriction may affect the quality of an early embryo in diet - induced obese mice with respect to various body weight and caloric intake (Chapter 3). In study (I), women preferred a shorter dietary intervention with greater energy restriction (456 kcal per day) to gradual energy restriction (1200 kcal / day for the first week, and afterward, 456 kcal / day) prior to oocyte transfer. Women were able to comply with the VLCD during IVF treatment and both dietary groups achieved a significant weight loss (mean 6.3 %). In study (II), by using obese mice, the effect of rapid weight loss (mean 12 %) was observed after 5 days of energy restriction. Ovulation rate was greater in the Obese group (HFD) (55.6%) and equal in both Control (CD) and Energy Restricted (HF / ER) (44.4 %) groups. The HF / ER group showed higher fertilisation rate (80 %) than HFD and CD (55% and 45.5%, correspondingly). The blastocyst stage was reached by half of the cultured embryos in both HF / ER and HFD groups and 33 % in the CD group. The quality of embryos that completed blastocyst formation did not differ between groups. However, postfertilisation development in females fed a high fat diet was slower compared to CD and HF / ER groups. In conclusion, this work illustrated a weight management prior conception and use of VLCD during IVF treatment in clinical study needs further investigation with regard to the dietary duration, level of energy restriction and how this combination will influence IVF treatment outcomes. Furthermore, as we were unable to determine the question of how the dietary intervention affects the quality of oocytes and the animal study illustrated a promising result, thus further studies are required.Thesis (M.Med.Sc.) -- University of Adelaide, School of Paediatrics and Reproductive Health, 200