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Stress urinary incontinence: where are we now, where should we go?

Stress urinary incontinence results from specific damage to the muscles, fascial structures, and nerves of the pelvic floor. Scientific data are accumulating about the nature of each of these injuries. As we begin to define the damage occurring in each element of the continence mechanism, we should be able to precisely select treatment plans on the basis of the abnormality found in individual patients. For example, a woman who has lost all neural control of her pelvic muscles could be saved the useless frustration of attempting pelvic muscle strengthening, whereas a woman with intact but weak muscles can be made continent with exercise. Before these advances can be realized, we must change our current empiric approach that assigns women to treatment because they have stress urinary incontinence to one that asks about the status of each part of the continence mechanism.

Female↗

Increased pressure during retrograde cerebral perfusion in an acute porcine model improves brain tissue perfusion without increase in tissue edema.

BACKGROUND: There is a significant lack of scientific data to support the clinically accepted view that 25 to 30 mm Hg is the maximum safe perfusion pressure during retrograde cerebral perfusion (RCP). This study was designed to investigate whether perfusion pressure greater than 30 mm Hg during RCP is beneficial to the brain during prolonged HCA in an acute porcine model. METHODS: Sixteen pigs underwent 120 minutes of circulatory arrest in conjunction with RCP at a perfusion pressure of either 23 to 29 mm Hg (group L, n = 8) or 34 to 40 mm Hg (group H, n = 8) at 15 degrees C, followed by 60 minutes of normothermic cardiopulmonary bypass. Cortical blood flow and oxygenation were measured continuously with a laser flowmeter and near-infrared spectroscopy, respectively. Tissue water content was measured at the end of the experiments. RESULTS: Brain tissue blood flow was significantly higher in group H than in group L (16.8% +/- 4.1% vs 4.8% +/- 0.9% of baseline, p < 0.01) during RCP. Brain oxygen extraction in group L reached a maximum (approximately 70%) immediately after starting RCP, whereas in group H it increased gradually and reached a maximum at 120 minutes of RCP, indicating a greater supply of oxygen to tissue in group H than in group L. After RCP, the ability of brain tissue to use oxygen was better preserved in group H than in group L, as indicated by tissue oxygen saturation and the deoxyhemoglobin level. There was no significant increase in tissue water content in either group (group H 79.2% +/- 0.3%, group L 79.1% +/- 0.4%) relative to normal control pigs (78.7% +/- 0.1%). CONCLUSIONS: In this acute porcine model, increasing perfusion pressure from 23-29 to 34-40 mm Hg during RCP increases tissue blood flow and provides better tissue oxygenation, without increasing tissue edema. The optimal perfusion pressure for RCP needs to be further investigated.

Animals↗

The nature of work-related neck and upper limb musculoskeletal disorders.

The nature of work-related musculoskeletal disorders of the neck and upper limbs is reviewed using both scientific data and the consensus view of experts, union bodies and government agencies across the European Union. Work-related musculoskeletal disorders describe a wide range of inflammatory and degenerative diseases and disorders. These conditions result in pain and functional impairment and may affect, besides others, the neck, shoulders, elbows, forearms, wrists and hands. They are work-related when the work activities and work conditions significantly contribute to their development or exacerbation but are not necessarily the sole determinant of causation. The classification and the need for standardised diagnostic methods for assessment of neck and upper limb musculoskeletal disorders are reviewed. These disorders are a significant problem within the European Union with respect to ill health, productivity and associated costs. The pathomechanisms of musculoskeletal disorders affecting tendons, ligaments, nerves, muscle, circulation and pain perception are reviewed and conceptual models for the pathogenesis of musculoskeletal disorders affecting the neck and upper limbs are presented. The epidemiological evidence on the work-relatedness of these disorders is discussed. A relationship between the performance of work and the occurrence of neck and upper limb musculoskeletal disorders is evident. Intervention strategies in the workplace for the reduction of both exposure and effect should focus upon factors within the work organisation as well as actively involving the individual worker. The current knowledge is sufficient to enable informed decisions to be made on future research needs and prevention strategies at the societal, organisational and individual level.

Adult↗

Providing emergency contraceptive pills "behind-the-counter": opinions among Minnesota healthcare providers.

We assessed strategies to increase access to emergency contraceptive pills (ECPs) among healthcare providers in Minnesota. We hypothesized that physicians, mid-level practitioners (nurse practitioners, certified nurse midwives and physician assistants) and pharmacists would support collaborative drug therapy agreements to enable pharmacist provision of ECPs without a prescription ("behind-the-counter"). We assessed these and other strategies to improve access to ECPs among a random sample of 1000 healthcare providers using mailed surveys. Obtaining a 50% response rate (n = 495), we discovered that the majority of total respondents (and a significant proportion of physicians) favored improving ECP availability "behind-the-counter", over-the-counter or both. Support among mid-level practitioners was more guarded: 39% of respondents supported pharmacist provision of ECPs and more than 20% wanted more information. Among pharmacists, 46% said they would participate in a collaborative protocol for provision of ECPs. Results demonstrate the degree of support and illuminate potential obstacles to pharmacist-provided ECPs. While there is general support among Minnesota providers regarding ECPs, a campaign to educate providers about recent scientific data on ECPs and collaborative drug therapy agreements should be initiated.

Attitude of Health Personnel↗

Prions and the human transmissible spongiform encephalopathies.

The last 5 years have seen the emergence of a new disease in humans (vCJD), mainly in the United Kingdom. This emergence has been accompanied by an explosion of scientific data on a novel group of the responsible infectious agents called prions and has profound implications for infection control and transfusion policies. Also of concern is the finding of prions in neural, gingival, pulpal, and salivary tissue in animal models and significant titers of infectivity from extraneural organs (particularly, in cases of vCJD, in lymphoreticular tissues). There is limited information on the presence of prion proteins in the oral tissues from human studies. Because of the differences in patterns of disease in animal models and in strains of prion protein, it is difficult to extrapolate directly these findings to humans, but it illustrates a potential for transmission by way of the dental route. High levels of infectivity may be present in tissues early in the incubation period and before clinical signs and symptoms. The dental profession must turn its attention to the routine decontamination of dental instruments to ensure that these procedures are performed to the highest regulatory standard. Clinicians and manufacturers must work closely together to develop instruments that are either single use or can be presented in a form that can be more easily decontaminated. Clinicians must pay close attention to manufacturers' decontamination instructions and must not reuse items designated as single use, such as endodontic files. Improvements in compliance with these requirements will not only reduce the risk of transmission of TSEs but also other less tenacious infectious agents.

Animals↗

The value of genotyping for apolipoprotein E alleles in relation to vitamin E supplementation.

The clinical utility of genotyping individuals for apolipoprotein E alleles remains controversial. The present summary reviews clinical and scientific data that suggest that vitamin E supplementation may be beneficial in individuals who carry the apolipoprotein E4 allele. We propose that early anti-oxidant intervention with vitamin E supplementation may have life-long beneficial effects for individuals who carry one or more apolipoprotein E4 alleles.

Alleles↗

Timing of onset of contraceptive effectiveness in Norplant implant users. Part I. Changes in cervical mucus.

OBJECTIVE: To provide scientific data regarding the changes in cervical mucus within the first hours to days after Norplant implant insertion and to estimate when the cervical mucus is hostile enough to suggest a contraceptive effect. DESIGN: Multicenter, clinical descriptive study. SETTING: Family planning clinics. PATIENT(S): Forty-two women who were between days 8 and 13 of their menstrual cycle and who had requested Norplant implants were admitted to the study. INTERVENTION(S): Cervical mucus and blood samples were obtained. MAIN OUTCOME MEASURE(S): Cervical mucus scores, sperm penetration distances, and serum levels of progesterone, estradiol, and levonorgestrel. RESULT(S): The median cervical mucus score observed at baseline was 6 ("fair"), indicating that the mucus was already somewhat hostile before insertion of the Norplant implants. The median scores declined to 5 at 12 and 24 hours and continued to decrease through day 7 to 2 ("poor"), a score that is judged as hostile to sperm penetration. Overall, 73% of all subjects had a poor cervical mucus score by 3 days after insertion; at 7 days after insertion, 90% exhibited poor mucus and none had a good score. There was a substantial drop in the overall median distance traveled by the vanguard sperm after 12 hours for each cervical mucus score grouping. The distance traveled decreased rapidly between 12 and 24 hours to < 0.5 cm in subjects with fair and poor mucus, and by day 3, 91% of the subjects exhibited poor sperm penetration. CONCLUSION(S): On the basis of our findings, deterioration of the quality of the cervical mucus and sperm penetration is evident by 24 hours after insertion, although not to a level that would suggest adequate protection until 72 hours after insertion. Therefore, we are confident in recommending that backup methods of contraception (e.g, condoms) need not be used for more than 3 days after insertion, even when the implants are inserted close to ovulation. These findings provide policy makers, clinic managers, and clinicians with important information about how they can improve client access to Norplant implants.

Adult↗

Nipple confusion: toward a formal definition.

The purposes of this article are to introduce a formal definition of nipple confusion and to propose various hypotheses concerning its cause. The term nipple confusion refers to an infant's difficulty in achieving the correct oral configuration, latching technique, and suckling pattern necessary for successful breast-feeding after bottle feeding or other exposure to an artificial nipple. Many early breast-feeding failures are attributed to nipple confusion, although scientific data are lacking to document its prevalence, the mechanisms involved, or various factors that predispose an infant to this phenomenon. Two classifications of nipple confusion are recommended to distinguish the impact of artificial nipples during the newborn period from their influence after breast-feeding is well established. Maternal and infant risk factors making an infant more susceptible to nipple confusion are discussed. Future studies are planned to help elucidate the nature of nipple confusion and identify the circumstances under which infants are most vulnerable to this phenomenon. Meanwhile, it would seem prudent for clinicians to identify newborns at risk for nipple confusion and to minimize the use of bottle feedings in such babies. Medically indicated supplements in the early days of life could be provided by alternative methods, such as cup, spoon, or dropper feeding, until breast-feeding can be established.

Bottle Feeding↗

Safe administration of influenza vaccine to patients with egg allergy.

OBJECTIVES: Specific recommendations for administering the influenza vaccine to patients with egg allergy are based on limited scientific data. The objectives of this investigation were to determine the safety of a 2-dose administration of an influenza vaccine to patients with egg allergy and to evaluate the usefulness of skin testing with the influenza vaccine before administration. STUDY DESIGN: In this multicenter clinical trial, clinical histories of egg allergy were confirmed by skin testing with egg and, if possible, by oral challenges with egg. Subjects with egg allergy received the vaccine in 2 doses, 30 minutes apart; the first dose was one tenth and the second dose nine tenths of the recommended dose as determined by age. Subjects without egg allergy were recruited as control subjects and received 1 age-determined dose of the vaccine. Skin prick tests with the influenza vaccine were performed on all subjects. RESULTS: From 1994 to 1997, 83 subjects with egg allergy and 124 control subjects were evaluated. The content of ovalbumin/ovomucoid was 0.1, 1.2, and 0.02 micrograms/mL, respectively in the 1994-95, 1995-96, and 1996-97 influenza vaccines. Results of vaccine skin prick tests were positive in 4 subjects with egg allergy and in 1 control subject. All patients with egg allergy tolerated the vaccination protocol without any significant allergic reactions. CONCLUSIONS: These results demonstrate that patients with egg allergy, even those with significant allergic reactions after egg ingestion, can safely receive an influenza vaccine in a 2-dose protocol when the vaccine preparation contains no more than 1.2 micrograms/mL egg protein.

Adolescent↗

Attitudes and use of complementary medicine in men with prostate cancer.

PURPOSE: Patients with cancer are increasingly incorporating complementary therapies into the overall treatment. We determine the prevalence and patterns of use of complementary therapies among patients with prostate cancer. MATERIALS AND METHODS: Patients attending 6 urology institutions for prostate cancer management completed a self-administered questionnaire on complementary therapy. All men diagnosed with prostate cancer were eligible, regardless of age, stage of disease or treatment. RESULTS: A total of 1,099 patients returned the questionnaire. The overall response rate was 78.5%. Complementary therapies had previously been or were currently being used by 23.5% (258) and 18.2% (200) of patients, respectively. Higher levels of education and income were associated with greater use of complementary therapy (p <0.002 by logistic regression). Patients with progressive disease or those primarily treated with hormones were most likely to use complementary therapy. Among the patients using complementary therapy 90% believed that it would help them live longer and improve quality of life, 60% believed it would relieve symptoms and 47% expected it to cure disease. CONCLUSIONS: Complementary therapies are used by a large number of patients with prostate cancer, particularly those with progressive disease or who have undergone multiple treatments. Health care providers need to recognize this growing pattern of use of complementary therapy. Among patients who use complementary therapy the perception of benefit is much greater than that supported by scientific data. Future research should aim to unravel the complex psychosocial dynamics that influence the decision to use complementary therapy by men with prostate cancer and to educate patients about the efficacy of such therapies.

Aged↗

The hyperlipoproteinemias.

The association of disturbances of plasma lipid transport and atherogenesis has been recognized, and scientific data continue to accumulate to explain this association from a mechanistic viewpoint. A number of recent clinical trials have shown that cholesterol-lowering therapy can prevent the complications of atherosclerosis. Consequently, the attention of physicians to therapeutic intervention has increased and public awareness to plasma cholesterol levels has been heightened. This article summarizes current knowledge of how plasma lipid transport is regulated. The classical primary hyperlipoproteinemias are considered and hyperlipoproteinemias occurring secondary to other diseases are discussed. Standard methods to diagnose the defined genetic hyperlipidemias are outlined, and new approaches to assess risk of atherosclerosis are examined. Finally, the role of dietary measures and drugs in lowering blood lipids and reducing risk of coronary heart disease is delineated.

Apoproteins↗

Lumbar intervertebral thermal therapies.

In hopes of improving outcomes for patients with discogenic pain, less invasive techniques that reduce trauma and shorten the recovery period have been developed. This article attempts to present a comprehensive description of minimally invasive techniques, specifically heat treatments, for lumbar disc disease. The goal is to inform and educate the reader on the various thermal therapies available for lumbar disc disease by evaluating the scientific data in an objective manner.

Chronic Disease↗

Management of the patella during revision total knee replacement arthroplasty.

Managing the patella and balancing the patellofemoral joint space is one of the most difficult aspects of performing a primary total knee replacement (TKR). The situation is compounded in the revision situation. Unfortunately, an otherwise well-performed TKR will fail because of problems with the patella or the extensor mechanism. This article discusses various aspects of the management of the patella and extensor mechanism during revision TKR with an objective of minimizing complications and maximizing functional outcomes. The topics covered include exposure of the patella and extensor mechanism during revision surgery, whether or not to remove all prior patellar implants, the technique for removal of a prior implant, the management of bone loss or fractures of the patella during revision TKR, the insertion (or noninsertion) and fixation of a new implant, and the balance of the patellofemoral joint space, including avoidance of patella baja or patella alta. A compilation of scientific and "no-so" scientific data and experience gleaned over the past 26 years of total knee replacement surgery will be presented.

Arthroplasty, Replacement, Knee↗

Neonatal circumcision.

The merits of neonatal circumcision continue to be debated hotly. Some argue that circumcision is a "uniquely American medical enigma." Most of the world's male population remains uncircumcised; however, most boys born in the United States continue to undergo neonatal circumcision. Review of existing literature supports that most children who are uncircumcised do well from a medical standpoint and, thus, the question of whether US health care practitioners are subjecting neonates to an unnecessary surgical procedure remains. The medical benefits of circumcision are multiple, but most are small. The clearest medical benefit of circumcision is the relative reduction in the risk for a UTI, especially in early infancy. Although this risk [figure: see text] is real, the absolute numbers are small (risk ranges from 1 in 100 to 1 in 1000), and one investigator has estimated that it may take approximately 80 neonatal circumcisions to prevent one UTI. In the case of a patient with known urologic abnormalities that predispose to UTI, neonatal circumcision has a clearer role in terms of medical benefit to the patient. Most of the other medical benefits of circumcision probably can be realized without circumcision as long as access to clean water and proper penile hygiene are achieved. Proper penile hygiene should all but eliminate the risk for foreskin-related medical problems that will require circumcision. Moreover, proper hygiene and access to clean water has been shown to reduce the rate of development of squamous cell carcinoma of the penis in the uncircumcised population. Proper techniques on the care of the foreskin are illustrated in the American Academy of Pediatrics pamphlet titled "How to care for the uncircumcised penis." Regarding the relationship between STDs and circumcision, patient education and the practice of low-risk sexual behavior make a far greater impact than does routine circumcision in hopes of reducing the spread of HIV and other STDs. Nevertheless, in areas where safe sexual practices are poorly adhered to, circumcision can have a relative protective effect against the transmission of HIV and other STDs. The medical harms of circumcision lie mainly in the 1% acute complication rate and the additional patients who require revision of their initial circumcision for cosmetic or medical reasons. Anecdotally, the authors see far fewer complications in the acute and long-term phase when the circumcision has been performed by someone with expertise and experience with the procedure. Thus, the authors routinely recommend to parents that, if they choose to have their newborns circumcised, they should seek out an experienced practitioner. A negative psychologic and sexual impact of circumcision has been argued, but solid, scientific data are lacking. Special interest groups have argued that perhaps the greatest harm of circumcision is in performing an operation without a clear indication. Many of these groups have claimed that performing a routine neonatal circumcision is akin to performing a surgical procedure without a clear medical benefit, and in an infant, that is akin to surgery without informed consent. Although this is an extreme posture, the clinician can understand the emphasis on trying to provide invasive medical services only when a clear medical benefit is expected, especially when treating an infant or child. Deciding whether or not to circumcise an infant continues to challenge many new parents. Clearly, the procedure provides potential medical benefits and potential risks. It is difficult to say whether the benefits outweigh the risks for all male infants. Further complicating the decision for many American parents is that, in some areas of the United States, there exists an unexplained positive cultural connotation with neonatal circumcision. For these reasons, parents who actively choose to keep their sons uncircumcised need to be encouraged to make this decision forthrightly. Parents who choose to have their children circumcised also should be encouraged to actively seek an experienced practitioner who can afford the child adequate local analgesia.

Analgesia↗

Alternatives to classic randomized trials.

Randomized clinical trials are regarded as the most credible way of generating scientific data that compare the benefits of different therapies. However, randomized trials present difficulties in their execution. Often physicians are unwilling to participate in such studies because they do not wish to inform the patient that the treatment program will be chosen by a chance mechanism. They believe that such a discussion may compromise the physician-patient relationship. Alternatives to classic randomized trials have been discussed. Also considered are some aspects of the strategy of clinical experimentation. It has been pointed out that the initiation of definitive Phase III trials made on the basis of little prior expectation of success ("trying something out") tends to generate false-positive results.

Clinical Trials as Topic↗

Preventing bloodborne pathogen transmission from health-care workers to patients. The CDC perspective.

The development of recommendations to manage the risk of bloodborne pathogen transmission from health-care workers to patients during invasive procedures has been difficult, primarily because of the limitations of available scientific data. Ultimately, both health-care workers and patients will be protected best by compliance with infection control precautions and by development of new instruments, protective equipment, and techniques that reduce the likelihood of intraoperative blood exposure without adversely affecting patient care.

Blood-Borne Pathogens↗

Molecular handling of cadmium in transporting epithelia.

Cadmium (Cd) is an industrial and environmental pollutant that affects adversely a number of organs in humans and other mammals, including the kidneys, liver, lungs, pancreas, testis, and placenta. The liver and kidneys, which are the primary organs involved in the elimination of systemic Cd, are especially sensitive to the toxic effects of Cd. Because Cd ions possess a high affinity for sulfhydryl groups and thiolate anions, the cellular and molecular mechanisms involved in the handling and toxicity of Cd in target organs can be defined largely by the molecular interactions that occur between Cd ions and various sulfhydryl-containing molecules that are present in both the intracellular and extracellular compartments. A great deal of scientific data have been collected over the years to better define the toxic effects of Cd in the primary target organs. Notwithstanding all of the new developments made and information gathered, it is surprising that very little is known about the cellular and molecular mechanisms involved in the uptake, retention, and elimination of Cd in target epithelial cells. Therefore, the primary purpose of this review is to summarize and put into perspective some of the more salient current findings, assertions, and hypotheses pertaining to the transport and handling of Cd in the epithelial cells of target organs. Particular attention has been placed on the molecular mechanisms involved in the absorption, retention, and secretion of Cd in small intestinal enterocytes, hepatocytes, and tubular epithelial cells lining both proximal and distal portions of the nephron. The purpose of this review is not only to provide a summary of published findings but also to provide speculations and testable hypotheses based on contemporary findings made in other areas of research, with the hope that they may promote and serve as the impetus for future investigations designed to define more precisely the cellular mechanisms involved in the transport and handling of Cd within the body.

Absorption↗

Persistent organic pollutants in environment of the Pearl River Delta, China: an overview.

In the Pearl River Delta of China, the rapidly developing industrial and agricultural activities, municipal development and use of chemicals caused serious environmental problems. This report summarizes the published scientific data on POPs in the environment of the Pearl River Delta, including the levels of POPs in the air, water, soil, river and estuarine sediments, the marine organisms like fish and shellfish in this region. The data preliminarily reveal the state of contamination in this region and give insight into the fate of POPs in this sub-tropical area. However, most research in this area is limited to a few kinds of POP compounds.

Animals↗