Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An electrode system was developed consisting of two 8 mm long 0.2 mm diameter silver-coated copper wires arranged parallel to each other 8 mm apart and held in contact with the skin by means of an acoustically transparent plastic adhesive tape. This system was attached to the upper arms of young adult volunteers who increased the voltage of the rectangular electrical pulses supplied to the electrodes until a reproducible sharp prickling pain sensation was perceived. A one inch diameter physiotherapy transducer was positioned over the electrode site so that ultrasound could be administered throughout the measurement period. The experiments were performed single blind to eliminate any subjective bias on the part of the volunteers. Preliminary experiments established that highly reproducible (+/- 3 to 4%) pain threshold perception values could be obtained, and that these values were not affected by changes in (a) the duration of the "on" time of the electrical pulses between 1.5 and 48 ms, (b) the contact pressure between the transducer and the electrode site, (c) the time interval between successive threshold measurements (providing that an unacceptable level of oedema was not produced around the electrodes), and (d) whether or not a test measurement was preceded by a control. Ultrasound exposure via a direct contact technique consistently produced a statistically significant (p less than 0.05) decrease in the perception threshold for electrical pain. This effect usually developed within 30-60 s and its magnitude increased both with increasing intensity (rising to 20.7 +/- 0.57% at an SATA intensity of 0.43 W/cm2 at 1.1 MHz) and with increasing frequency at the same ultrasonic intensity. Delivering the same amount of ultrasonic energy in the form of 2 ms bursts at several different peak intensities produced exactly the same reduction in pain threshold perception. These results indicate a thermal interaction mechanism, and similar threshold changes could be obtained by heating or cooling the electrode site by nonacoustic means. The inclusion of a thermocouple junction between the electrode wires showed that temperature increases of up to 10 degrees C could be produced when the transducer was in direct contact with the tape over the electrodes. The volunteers were not aware of these temperature increases which were primarily caused by heating of the transducer face. If the temperature of the skin surface is kept constant by interposing a thermostatted water path between the transducer and the electrode system, then similar ultrasound exposures had no detectable effects upon the electrical pain perception threshold.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effects of MHz ultrasound on electrical pain threshold perception in humans. 330 84

Despite the introduction of new intrauterine devices (IUDs), the most important complication involving their use continues to be excessive menstrual bleeding. IUD use in developing countries with women who are already depleted in body iron stores may prove to be deleterious to their health. Mean amounts of menstrual blood loss (MBL) for women not using contraception in the western world is about 32 ml. This mean is increased to 52-72 ml with use of the Lippes loop and other non-medicated devices up to 24 months after insertion. For the Copper-7 and Copper-T-200 devices this mean increase is to 37-40 ml in the first month, decreasing to 30-38 ml at 12 months after IUD insertion. In the users of the Multiload-250 IUD at one month post-insertion the MBL is from 56 to 63 ml and from 36 to 39 ml at 24 months of use. The mean Multiload-375 device users at one month after insertion lose a mean of 45-73 ml at 24 months, 35-50 ml. With the progestogen-releasing IUD mean MBL is 27-36 ml at 1 month and 9-13 ml at 12 months post-insertion. Intermenstrual blood loss is significant only in the first month of use for all IUDs. Discontinuation rates for pain and bleeding with non-medicated IUDs are from 11.0-19.6 per 100 women per year, and for the copper IUDs 4.4 to 6.8 per 100 women in the first year of use. The main problem with prolonged menstrual bleeding is depletion of the body iron stores; this is highly significant with non-medicated devices, less important with copper devices and conversely, iron stores are increased in users of progestogen-releasing devices. This is based on serum ferritin measured up to 24 months after insertion. The ferritin values correlated well with the volumes of MBL. It is suggested, especially for women with low body iron stores, that there is an order of preference for IUDs to be used. This should be: firstly, the progestogen-releasing devices; secondly, the Copper-T and Copper-7 IUDs; thirdly the larger surface copper devices (Cu-T-220C, Multiload 250 and 375, Cu-T-380). Non-medicated devices are not to be recommended for these women.
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PMID:Quantitative studies on menstrual blood loss in IUD users. 331 22

This review covers eicosanoid metabolism in human uterine tissues, in normal menstrual cycles, menorrhagia, and IUD contraception. Since measuring tissue level of prostaglandins (PGs) leads to artifacts, recent studies have involved tissue culture, superfusion and histochemistry, to analyze arachidonic acid metabolism, in endometrium, its tissues, and myometrium. First, it was established that Pgf2alpha and PGE2 are the primary PGs elaborated by human endometrium. The enzyme that produces Pgf2alpha, cyclooxygenase, is located primarily in the glandular endothelium. Pgf2alpha is under estrogen receptor control. Progesterone reduces Pgf2alpha and antiprogestogens increase it. In normal menstrual cycles, both PGs are highest in late luteal phase. In women with menorrhagia, defined as menstrual blood loss over 90 ml, the Pgf2alpha:PGE2 ratio is abnormally low, a reasonable finding since Pgf2alpha is vasoconstrictive, and PGE2 is a vasodilator. Another vasodilator PG, prostacyclin or PGI2, may be abnormally high in women with excessive bleeding. Some experiments on endometrium and myometrium, cultured apart and together, suggest that there may be flow of substrates of the PG pathways such that less Pgf2alpha is available in this condition. Using radiolabelled arachidonic acid, researchers concluded that the Pgf2alpha pathway may be saturated because of substrate being incorporated into excess triglycerides, leading to alternative PG release. Another theory proposes that PG antagonist drugs which block menstrual pain may also lower synthesis of leukotrienes, an eicosanoid that causes vasoconstriction as well as inflammation and pain. There have been no studies comparable to the tissue culture work cited above concerning IUDs. Some explorations of leukocyte PG metabolism and the effects of copper are relevant to the conclusions about PGE2 as a vasodilator. There could also be an alteration of locally produced thromboxanes and prostacyclins on blood clotting in IUD wearers.
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PMID:The role of prostaglandins and allied substances in uterine haemostasis. 331 24

Intrauterine contraception is characterized by reliability, ease of use and quick return of fertility upon removal. The life of the old Copper T was 3 years. Newer copper IUDs were developed to decrease the chance of pregnancy. Tolerance, however, was not increased. Pregnancy indexes with the newer intrauterine devices ranged from 0.3 - 2.1. Bleeding and pain are typical side effects of IUD prevention. The IUD can come out by itself because of poor placement or unsuitability of the uterus for this type of contraception. All IUDs, except ones that secrete hormones, increase bleeding and pain. Infection has been observed to be another problem, according to epidemiological studies conducted in the 1970s. Contributing factors are the shape of the device and its placement. Women with multiple partners have an increased risk of infertility. A tendency to develop venereal disease is a contraindication for IUD use. Studies regarding the higher incidence of ectopic pregnancy are controversial. Individuals affected by this usually are found to have had higher chlamydia antibody levels. Careful selection of user, counseling and follow-up are important for successful IUD contraception.
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PMID:[Contraceptive coils and their problems]. 333 Nov 43

The bacterial flora of the cervix and vagina were examined in 108 patients who had copper IUDs removed and in 66 controls at the Maternity Hospital and Maternal Welfare Clinics in Kuwait. The IUDs removed were the Nova-T, Copper 7, and Cu 250. 15 of the women having IUDs removed had pelvic inflammatory disease; 21 had irregular bleeding; 11 had suprapubic pain, vaginal discharge, or uterine perforation; and 51 were asymptomatic. Actinomyces species, particularly Actinomyces israelii, and Arachnia propionica were isolated from 16 of the IUD wearers but only 2 of the controls. Lactobacillus species were isolated from 10 of the IUD wearers and 25 of the controls. Anaerobic cocci were isolated from 13 device wearers and 12 controls. Except for Actinomyces, anaerobic bacteria were isolated from controls more often than from the IUD wearers. Copper is known to have an antibacterial effect on gram-positive anaerobes, and even Actinomyces was absent from IUD wearers who had worn the device less than a year, i.e., during the period of maximum copper release. Moreover, no significant difference was found in the patients in the different clinical groups. The presence of an IUD does promote colonization of the genital tract by Actinomyces. However, other factors must be considered in the development of pelvic inflammatory disease. The creation of an acidic environment by some bacteria, such as Lactobacillus, may promote the growth of some pathogens, while inhibiting the growth of others. Furthermore, the insertion of an IUD breaches the protective barrier of the cervical mucus, and the IUD tail creates a transmission link into the uterus.
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PMID:The effect of a copper intra-uterine contraceptive device on the microbial ecology of the female genital tract. 335 91

Diagnostic efficacy of hysterography was evaluated in 66 women (24-35 years old) who received an application of Copper-T (34) or Nova-T (32) IUD. The group included 44 primipara, 12 secundipara, and 10 nullipara. The patients were examined within 6-24 months after IUD application. All patients had subjective complaints associated with the use of IUD (profuse and painful menses, pain during the intercourse, hemorrhage between menstruations). At gynecological examination, 57 women were found to have normal position of the uterus, while 13 had uterus in retroposition. Hysterography with the water-soluble triiodoorganic contrast medium isteropac showed penetration of the IUD arms into the uterine cavity (24 out of 66), dislocation of the IUD (15), changes in the shape of the IUD (16), presence of synechiae (5), and perforation of the uterine wall (6). Penetration of the IUD into the myometrium was found to cause inflammatory changes.
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PMID:[Use of hysterography as a rapid method for determining complications occurring in the presence of an intrauterine pessary]. 341 2

37 consecutive patients who presented with absent or snapped strings and failed attempts at IUD removal by hooks or curette were referred for hysteroscopy/laparotomy following a pelvic x-ray to exclude unrecognized spontaneous expulsion of the device. The IUD was extrauterine in 19 patients and incarcerated in the uterine cavity in the remaining 18 patients. 17 of the 19 extrauterine devices were copper containing and 2 were inert Lippes Loop IUDs. In all cases, copper devices were associated with dense adhesions. Only 2 patients complained of any abdominal pain. The IUD type among the 18 patients with intrauterine translocated devices was the Lippes Loop in 15 cases and the Copper T in the remaining 3 cases. 6 of these patients had complained of excessive bleeding with pain. Hysteroscopy is invaluable to remove embedded and fragmented IUDs. It is suggested that all devices translocated into the abdomen be removed to avoid potential complications. Laparotomy is the method of choice to remove medicated devices given the dense adhesions often associated with bowel loops. Risk factors considered to be associated with translocation include postpartum insertion, inserter skill, insertion technique, and the status and configuration of the cervix and uterus.
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PMID:Management of translocated and incarcerated intrauterine contraceptive devices. 346 43

Two IUDs (Copper T 220 C and Alza T IPCS 52) were comparatively studied by randomized insertions in 200 Thai women who attended the Family Planning Clinic at the Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University. Point estimates of the pregnancy rate and rate of removal for bleeding and pain at 18 months were lower for the copper device than for the Alza T IPCS 52, but neither these nor any other pertinent event rates reached statistical significance. Study of the Alza device was halted before the completion of 2 years because reports from other centres indicated an unacceptable pregnancy rate beyond 2 years.
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PMID:A comparative clinical trial of Copper T 220 C and Alza T IPCS 52 intrauterine devices in Thai women. 353 Jun 33

This comparative study evaluated the acceptability and effectiveness of 3 IUDs--the Steel Ring, the V-shaped Copper 200 (VCu200), and the T-shaped Copper 200c (TCu200c)--in parous Chinese women. 200 healthy women 20-39 years of age were randomly allocated to each of the 3 treatment groups. All subjects had had at least 1 full-term pregnancy. The TCu200c and VCu200 performed significantly better than the Steel Ring in terms of pregnancy and expulsion rates, at both the 1 and 2-year follow up; however, the latter device had significantly lower rates of removal for pain and bleeding. At 2 years, there had been 14 pregnancies in women using the Steel Ring, 6 in VCu200 users, and 2 in users of the TCu200c device; expulsions totalled 25, 3, and 7, respectively. Total use-related discontinuations at 2 years were 42, 28, and 34, respectively, among users of these 3 IUDs. Further evaluation will be conducted after 5 years of continuous use.
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PMID:A randomized comparative clinical evaluation of the Steel Ring, the VCu200 and the TCu220c IUDs. 353 Jun 34

Complications associated with postabortion insertion of the Delta T and Copper T 200 IUDs were compared in 195 women. All insertions were performed with an inserter. There were no reported incidents of inserter-related problems, pelvic pain, or other complications at insertion. At follow-up, intermenstrual spotting was the most frequently reported complaint, involving 14 women (18.2%) in the Delta T group and 7 women (9.5%) in the TCu group. 8 Delta T acceptors (10.4%) and 12 TCu acceptors (16.2%) experienced intermenstrual bleeding. Intermenstrual pain was reported by 7 (9.1%) Delta T users and 4 (5.4%) TCu users. Other primary bleeding and pain complaints included menorrhagia, reported by 9 (11.7%) Delta T users and 9 (12.2%) TCu users, and dysmenorrhea, reported by 5 (6.5%) Delta T users and 4 (5.4%) TCu users. Pelvic inflammatory disease (PID) confined to the uterus was diagnosed in 9 (11.7%) Delta T acceptors and 5 (6.8%) TCu acceptors. 7 women (9.1%) in the Delta T group and 8 women (10.8%) in the TCu group reported PID confined to the adnexa. 1 woman from each group had PID confined to the uterus and adnexa and 5 TCu users reported PID beyond the uterus and adnexa. Of the 36 women diagnosed with PID, 9 had their devices removed. There was 1 pregnancy in the Delta T group and 1 device from each group was expelled. There were 3 removals for pain and bleeding in the Delta T group and 4 removals for this reason in the TCu group. The 6-month continuation rate was 85.5 for the Delta T device and 82.2 for the TCu IUD. Given the high incidence of spotting, intermenstrual bleeding, and PID recorded in this sample, insertion of an IUD in the immediate postabortion period is not recommended.
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PMID:A comparison of the delta copper T and the copper T 200 in Bologna, Italy. 372 92


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