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David A Grimes

Publications and source records attributed to David A Grimes.

At least 37 records · Page 2Linked to original sources
PubMed2005

Nonhormonal drugs for contraception in men: a systematic review.

UNLABELLED: Nonhormonal drugs for contraception in men may have advantages over hormonal methods. The nonhormonal methods can have more rapid onset and less interference with androgen-dependent functions. This systematic review summarizes the clinical studies evaluating nonhormonal drugs administered to men for contraception. Relevant clinical results were found for gossypol, which is derived from the cotton plant, and for extracts of Tripterygium, a plant used in Chinese traditional medicine. Randomized, controlled trials were available on the efficacy of gossypol and on the effect of gossypol on potassium levels. Gossypol had problems with low efficacy and toxicity. For Tripterygium, 2 observational studies described men who were treated for rheumatoid arthritis. Although sperm density was lower among those taking Tripterygium, later reports indicated some toxicity. Nonclinical research continues on isolates of Tripterygium. No clinical studies for contraception in men were found for nonhormonal vaccines or neem, which is also a plant used for medicinal purposes. Clinical trials studied injecting styrene maleic anhydride into the vas deferens, but no comparative data were provided. At this time, no safe and effective nonhormonal drug is available for contraception in men. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader should be able to state that the number of studies concerning the use of nonhormonal drugs for male contraception are very limited, point out that the two nonhormonal drugs used to a small degree have varying results and serious side effects, and recall that there are limited clinical studies on use of vas deferens injections and vaccines in humans.

Contraceptive Agents, Male↗
PubMed2004

The gene for paroxysmal non-kinesigenic dyskinesia encodes an enzyme in a stress response pathway.

Paroxysmal non-kinesigenic dyskinesia (PNKD) is characterized by spontaneous hyperkinetic attacks that are precipitated by alcohol, coffee, stress and fatigue. We report mutations in the myofibrillogenesis regulator 1 (MR-1) gene causing PNKD in 50 individuals from eight families. The mutations cause changes (Ala to Val) in the N-terminal region of two MR-1 isoforms. The MR-1L isoform is specifically expressed in brain and is localized to the cell membrane while the MR-1S isoform is ubiquitously expressed and shows diffuse cytoplasmic and nuclear localization. Bioinformatic analysis reveals that the MR-1 gene is homologous to the hydroxyacylglutathione hydrolase (HAGH) gene. HAGH functions in a pathway to detoxify methylglyoxal, a compound present in coffee and alcoholic beverages and produced as a by-product of oxidative stress. Our results suggest a mechanism whereby alcohol, coffee and stress may act as precipitants of attacks in PNKD. Stress response pathways will be important areas for elucidation of episodic disease genetics where stress is a common precipitant of many common disorders like epilepsy, migraine and cardiac arrhythmias.

Animals↗
PubMed2004

Induced abortion: an overview for internists.

Internists care for many women who have had abortions and many who will seek abortions in the future. Each year, about 2% of all women of reproductive age have an abortion. Women having abortions tend to be young, white, unmarried, and early in pregnancy. Most abortions are done by suction curettage under local anesthesia in a freestanding clinic. However, medical abortion is growing in popularity as a nonsurgical alternative. The regimen approved by the U.S. Food and Drug Administration specifies mifepristone, 600 mg orally, followed 2 days later by misoprostol, 400 microg orally (within 49 days from last menses). Recent studies have recommended alternative approaches, such as mifepristone, 200 mg orally, followed in 1 to 3 days by misoprostol, 800 microg vaginally (up to 63 days). Medical abortion can be provided by a broader variety of physicians than can surgical abortion. The overall case-fatality rate for abortion is less than 1 death per 100,000 procedures. Infection, hemorrhage, acute hematometra, and retained tissue are among the more common complications. Referral back to the original abortion provider for management is advisable. Overall, induced abortion does not lead to late sequelae, either medical or psychiatric. Of importance, no link exists between induced abortion and later breast cancer. For physicians who are asked to help with a referral, the National Abortion Federation and Planned Parenthood Federation of America have helpful Web sites and networks of high-quality clinics. The cost of abortion (currently about 372 dollars at 10 weeks) has decreased in recent decades. Provision of ongoing contraception and encouragement of emergency contraception can reduce unintended pregnancies and the need for abortion.

Abortifacient Agents↗
PubMed2004

Mifepristone and misoprostol versus dilation and evacuation for midtrimester abortion: a pilot randomised controlled trial.

OBJECTIVE: To test the feasibility of mounting a randomised controlled trial comparing mifepristone-misoprostol versus dilation and evacuation (D&E) for midtrimester abortion. DESIGN: Pilot randomised controlled trial. SETTING: University of North Carolina Hospitals, Chapel Hill, North Carolina. POPULATION: Women aged 18 years or older and without prior uterine operations who requested abortion at 14-19 menstrual weeks of gestation from January 2002 to January 2003. METHODS: Participants received either mifepristone 200 mg by mouth followed in two days by vaginal then oral misoprostol (Aberdeen regimen) or D&E after one or two days of laminaria preparation. Care was provided by residents under faculty supervision. MAIN OUTCOME MEASURES: Enrolment rate and acceptability of and adverse events associated with methods. RESULTS: The trial was stopped at one year because of slow enrolment. Of 47 women eligible for the trial, 29 (62%) declined participation, primarily because of a preference for D&E abortion. Among the 18 participants enrolled, nine were randomised to treatment with mifepristone-misoprostol and 9 to D&E. Compared with D&E, mifepristone-misoprostol abortion caused more pain and adverse events, although none was serious. CONCLUSIONS: Our findings concerning acceptability and adverse events should be considered hypothesis-generating; they may prove useful in planning a larger randomised controlled trial. Such a trial will be difficult to mount in the US. Hence, we suggest that it be done in a setting where labour-induction abortion is the norm.

Abortifacient Agents↗
PubMed2004

Combination estrogen-progestin contraceptives and body weight: systematic review of randomized controlled trials.

OBJECTIVE: Many women and clinicians believe that combination estrogen-progestin contraceptive use can lead to weight gain. This concern can deter women from starting hormonal contraception or lead to premature quitting. This review evaluated the association between combination contraceptive use and change in body weight. DATA SOURCES: The computerized databases CENTRAL, MEDLINE, EMBASE, Popline, and LILACS (from their inception to 2002) were used to conduct this review. Known investigators and manufacturers were contacted for information about other trials not discovered in the database search. METHODS OF STUDY SELECTION: All English-language, randomized controlled trials measuring weight change that were at least 3 treatment cycles in duration and that compared a combination contraceptive to a placebo or to a combination contraceptive that differed in drug, dosage, regimen, or study length were eligible for inclusion. Of the 570 reports of randomized controlled trials of eligible interventions that were identified, 42 trials were included in the systematic review. TABULATION, INTEGRATION, AND RESULTS: Two reviewers independently abstracted data from the eligible trials using a standard form. Depending on the data available, the weighted mean difference using a fixed effect model with 95% confidence intervals was calculated for the mean change in weight between baseline and posttreatment measurements or the Peto odds ratio with 95% confidence intervals was calculated by using the proportion of women who gained or lost more than a specified amount of weight. The 3 placebo-controlled, randomized trials did not find evidence supporting a causal association between combination oral contraceptives or a combination skin patch and weight gain. Most comparisons from the 40 trials that compared 2 or more combination contraceptives showed no substantial difference in weight. In addition, discontinuation of combination contraceptives because of weight gain did not differ between groups when this factor was studied. CONCLUSION: Available evidence is insufficient to determine the effect of combination contraceptives on weight, but no large effect is evident.

Adult↗
PubMed2004

Routine follow-up visits after first-trimester induced abortion.

Routine follow-up visits after abortion are intended to confirm that the abortion is complete and to diagnose and treat complications. Many clinicians also take advantage of the follow-up visit to provide general reproductive health care: discussing contraceptive plans and providing family planning services; diagnosing sexually transmitted infections; performing a Pap test or discussing abnormal Pap results. We reviewed the evidence related to the routine postabortion follow-up visit. Other than mifepristone medical abortion performed at 50 days of gestation or later and methotrexate medical abortion, we found little evidence that mandatory follow-up visits typically detect conditions that women themselves could not be taught to recognize. In addition, the natural history of the most severe complications after abortion-infection and unrecognized ectopic pregnancy-have time courses inconsistent with the usual timing of the follow-up visit. Costs associated with this visit can be great. These include travel expenses, lost wages, child-care expenses, privacy and emotional burdens for women, and scheduling disruptions and the related opportunity costs caused by "no-shows" for the provider. Follow-up appointments should be scheduled for those women likely to benefit from a physical examination. For the remainder of women, simple instructions and advice about detecting complications, possibly coupled with telephone follow-up, might suffice. Although arguably valuable in their own right, counseling, family planning services, or sexually transmitted infection diagnosis and treatment should not be so inflexibly bundled with postabortion care. Protocols that require in-person follow-up after abortion may not make the best use of a women's time or abilities, or of the medical system.

Abortion, Induced↗
PubMed2003

Unsafe abortion: the silent scourge.

An estimated 19 million unsafe abortions occur worldwide each year, resulting in the deaths of about 70,000 women. Legalization of abortion is a necessary but insufficient step toward improving women's health. Without skilled providers, adequate facilities and easy access, the promise of safe, legal abortion will remain unfulfilled, as in India and Zambia. Both suction curettage and pharmacological abortion are safe methods in early pregnancy; sharp curettage is inferior and should be abandoned. For later abortions, either dilation and evacuation or labour induction are appropriate. Hysterotomy should not be used. Timely and appropriate management of complications can reduce morbidity and prevent mortality. Treatment delays are dangerous, regardless of their origin. Misoprostol may reduce the risks of unsafe abortion by providing a safer alternative to traditional clandestine abortion methods. While the debate over abortion will continue, the public health record is settled: safe, legal, accessible abortion improves health.

Abortion, Induced↗
PubMed2003

Effect of lactation on maternal body weight: a systematic review.

UNLABELLED: The impact of lactation on maternal weight after delivery remains unclear. To address this question, we performed a systematic review of the literature. We searched PubMed, POPLINE, EMBASE, and LILACS computerized databases for relevant articles and classified the evidence using the U.S. Preventive Services Task Force rating system. We found 42 studies, of which 28 contained relevant information: 15 prospective cohort studies, 1 retrospective cohort study, 1 cross-sectional study, and 11 case-series reports. The methods used in these studies varied widely, thus precluding aggregation of results. Level II-2 and III evidence supports a class "C" recommendation: insufficient evidence exists to support an effect of lactation on maternal weight after delivery. Better longitudinal studies with a clear definition of breast-feeding; clear, specific outcome measures; study periods extending 1 or 2 years after delivery; and better control of potentially confounding factors will be needed to resolve this question. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader will be able to compile the literature on the effect of lactation on maternal weight, to compare the various studies, and to summarize the data on the effect of lactation on maternal weight gain.

Body Weight↗
PubMed2002

Uncertainty.

Explore the source record for details and available documents.

Anecdotes as Topic↗
PubMed2002

Emergency contraception.

Emergency contraception is used to prevent pregnancy after a coital act not adequately protected by a regular method of contraception. In contrast to early medical abortion, emergency contraception prevents a pregnancy from starting and does not disrupt an established pregnancy. The most commonly used approaches consist of two oral doses of contraceptive steroids. The levonorgestrel-only regimen (levonorgestrel, 0.75 mg, repeated in 12 hours) appears to be more effective and better tolerated than the Yuzpe regimen (ethinyl estradiol, 100 microg, and levonorgestrel, 0.5 mg, repeated in 12 hours). In the largest randomized, controlled trial to date, levonorgestrel prevented about 85% of pregnancies that would have occurred without its use. Hormonal emergency contraception has no known medical contraindications, although it is not indicated for suspected or confirmed pregnancy. However, if hormonal emergency contraception is inadvertently taken in early pregnancy, neither the woman nor the fetus will be harmed. Nausea and vomiting associated with the Yuzpe regimen can be reduced by prophylactic use of meclizine. A strong medical and legal case exists for making hormonal emergency contraception available over the counter, as has happened in countries other than the United States. Easier access to and wider use of emergency contraception could dramatically lower the high rates of unintended pregnancy and induced abortion in the United States.

Age Factors↗
PubMed2002

Unequal group sizes in randomised trials: guarding against guessing.

We cringe at the pervasive notion that a randomised trial needs to yield equal sample sizes in the comparison groups. Unfortunately, that conceptual misunderstanding can lead to bias by investigators who force equality, especially if by non-scientific means. In simple, unrestricted, randomised trials (analogous to repeated coin-tossing), the sizes of groups should indicate random variation. In other words, some discrepancy between the numbers in the comparison groups would be expected. The appeal of equal group sizes in a simple randomised controlled trial is cosmetic, not scientific. Moreover, other randomisation schemes, termed restricted randomisation, force equality by departing from simple randomisation. Forcing equal group sizes, however, potentially harms the unpredictability of treatment assignments, especially when using permuted-block randomisation in non-double-blinded trials. Diminished unpredictability can allow bias to creep into a trial. Overall, investigators underuse simple randomisation and overuse fixed-block randomisation. For non-double-blinded trials larger than 200 participants, investigators should use simple randomisation more often and accept moderate disparities in group sizes. Such unpredictability reflects the essence of randomness. We endorse the generation of mildly unequal group sizes and encourage an appreciation of such inequalities. For non-double-blinded randomised controlled trials with a sample size of less than 200 overall or within any principal stratum or subgroup, urn randomisation enhances unpredictability compared with blocking. A simpler alternative, our mixed randomisation approach, attains unpredictability within the context of the currently understood simple randomisation and permuted-block methods. Simple randomisation contributes the unpredictability whereas permuted-block randomisation contributes the balance, but avoids the perfect balance that can result in selection bias.

Bias↗
PubMed2002

Uses and abuses of screening tests.

Screening tests are ubiquitous in contemporary practice, yet the principles of screening are widely misunderstood. Screening is the testing of apparently well people to find those at increased risk of having a disease or disorder. Although an earlier diagnosis generally has intuitive appeal, earlier might not always be better, or worth the cost. Four terms describe the validity of a screening test: sensitivity, specificity, and predictive value of positive and negative results. For tests with continuous variables--eg, blood glucose--sensitivity and specificity are inversely related; where the cutoff for abnormal is placed should indicate the clinical effect of wrong results. The prevalence of disease in a population affects screening test performance: in low-prevalence settings, even very good tests have poor predictive value positives. Hence, knowledge of the approximate prevalence of disease is a prerequisite to interpreting screening test results. Tests are often done in sequence, as is true for syphilis and HIV-1 infection. Lead-time and length biases distort the apparent value of screening programmes; randomised controlled trials are the only way to avoid these biases. Screening can improve health; strong indirect evidence links cervical cytology programmes to declines in cervical cancer mortality. However, inappropriate application or interpretation of screening tests can rob people of their perceived health, initiate harmful diagnostic testing, and squander health-care resources.

Ethics, Medical↗