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Sacroiliac joint pain and dysfunction.

The purpose of this current opinion on sacroiliac joint pain and dysfunction is to assist interventional pain physicians to apply appropriate treatment decisions and rationale to their patients in pain. Discussion of relevant scientific data and controversial positions will be provided. This review is intended to help characterize the sacroiliac joint as a pain generator, and explore its contribution to the differential diagnosis of low back pain. Historical, technical, and current treatment practice will be characterized against current evidence. Discussion will provoke support or criticism of the relevant scientific data, and general recommendations for interventional pain management physicians should be considered within the context of the individual practitioners skill and practice patterns. Current Opinion is not intended to provide a standard of care.

Journal Article↗

[Structure and functional features of enzymes from the Ca2+-phospholipid-dependent protein kinase family].

Present day scientific data about the Ca(2+)-phospholipid-dependent protein kinases structure and molecular mechanisms of their activity are summarized and analyzed in this review. Ca(2+)-phospholipid-dependent protein kinases family is well known to include a whole series of enzymes which are homologous by their structure. They play an important role in cell differentiation, growth and proliferation as well as signal transduction through the cytoplasmic membrane. They also take part in cell response realization by phosphorylation of target proteins. Now application of modern biochemical and biophysical methods provided for possibility of the clarification of these enzymes structure features. The great lot of experimental data about the molecular mechanisms of Ca(2+)-phospholipid-dependent protein kinases activity regulation by phosphatydyle serine, phorbol ethers, saturated and unsaturated fatty acids, calcium iones, autophosphorylation and holoferment phosphorylation by other kinases was obtained. As a model of Ca(2+)-phospholipide-dependent protein kinases regulation was their development on the base of the scientific data about this problem.

Calcium↗

[Can we reduce the episotomy rate?].

OBJECTIVES: Determine whether scientific evidence supports an "appropriate" episiotomy rate - and whether this rate can be reduced via medical intervention and or preventive actions during pregnancy or at the time of delivery. MATERIAL AND METHODS: A survey of the literature available on Medline and the Cochrane Library between 1980 and 2005 and dealing with the objectives of the present study was undertaken. RESULTS: In France, the national episiotomy rate should not reach 30%. A program aiming at continuous improvement in quality-of-care after episiotomy and including various actions - training courses, audits, presence of a staff leader, episiotomy rate feedback per midwife or obstetrician - could help reduce the use of episiotomies (grade B). There is insufficient scientific data available to recommend perineal massaging or pre-birth perineal physiotherapy (grade B), and the benefits of a pre-birth training course on the perineum are still to be assessed (grade C). A pregnancy-long support provided to a woman by the same professional could reduce the use of episiotomies but not resorting to perineum repair (grade B). The effects of various types of pre-birth training courses on the perineum are unknown (grade C). We lack scientific data to promote perineal massaging during labor (grade B). Some studies show that an upright position during the second stage of labor is less harmful to the perineum than the classical dorsal reclining position, however it can increase the possibility of post-partum hemorrhage (grade B). Scientific proof is not sufficient to advise favoring a particular type of pushing or a specific manner to release the baby's head (grade B). CONCLUSION: More randomized studies are necessary to assess the relevance of all these preventive measures as regards the use of episiotomies.

Adult↗

Exposure to exogenous estrogens in food: possible impact on human development and health.

There has been increasing concern about the impact of environmental compounds with hormone-like action on human development and reproductive health over the past decades. An alternative but neglected source of hormone action that may be considered in this connection is hormone residues in meat from husbandry animals treated with sex steroid hormones for growth promotion. Treatment of cattle with naturally occurring or synthetic sex hormones may enhance lean muscle growth and improve feed efficiency and is therefore a very cost effective procedure for cattle producers who have used it for decades in some Western countries, including the USA and Canada. The Joint Food and Agricultural Organisation/World Health Organisation (FAO/WHO) expert committee on food additives (JECFA) and the US Food and Drug Administration (FDA) considered, in 1988, that the residues found in meat from treated animals were safe for the consumers. We have re-evaluated the JECFA conclusions regarding the safety of estradiol residues in meat in the light of recent scientific data, with special emphasis on estradiol levels in prepubertal children. These levels are needed for estimates of the normal daily production rates of estradiol in children, who may be particularly sensitive to low levels of estradiol. In our opinion, the conclusions by JECFA concerning the safety of hormone residues in meat seem to be based on uncertain assumptions and inadequate scientific data. Our concerns can be summarized as follows. 1) The data on residue levels in meat were based on studies performed in the 1970's and 1980's using radioimmunoassay (RIA) methods available at the time. The sensitivity of the methods was generally inadequate to measure precisely the low levels found in animal tissues, and considerable variation between different RIA methods for measuring steroids exists. Therefore the reported residue levels may be subject to considerable uncertainty. 2) Only limited information on the levels of the various metabolites of the steroids was given despite the fact that metabolites also may have biological activity. 3) Reliable data on daily production rates of steroid hormones were and are still lacking in healthy prepubertal children. This lack is crucial as previous guidelines regarding acceptable levels of steroid residues in edible animal tissues have been based on very questionable estimates of production rates in children. Thus, even today the US FDA bases its guidelines on the presumably highly overestimated production rates in prepubertal children given in the JECFA 1988 report. 4) The possible biological significance of very low levels of estradiol is neglected. In conclusion, based on our current knowledge possible adverse effects on human health by consumption of meat from hormone-treated animals cannot be excluded.

Animals↗

The validity of claims made in orthopaedic print advertisements.

PURPOSE: Orthopaedic surgeons are frequently presented with advertisements for orthopaedic and medical products in which companies make claims of clinical and scientific fact. This study was designed to evaluate the statements made in orthopaedic print advertisements and determine whether they are supported by scientific data. METHODS: Fifty statements from fifty advertisements were chosen at random from six peer-reviewed orthopaedic journals. The companies that placed the advertisements were contacted to provide supporting data for the statement of clinical or scientific fact. Three senior orthopaedic surgeons evaluated the data for quality and support. A high-quality study was defined as a study that could be published in the peer-reviewed literature. A well-supported statement was defined as a statement with enough supporting evidence to be used in clinical practice. The evaluating surgeons were blinded to product and company identification. RESULTS: The supporting data were from a published source for eighteen claims (36%), from a presentation at a public forum or a scientific meeting for twelve claims (24%), or were "data on file" only at the company for twelve claims (24%). Interobserver agreement among the surgeons evaluating the advertisements for quality and support was good (the average intraclass correlation coefficient was 0.72). Of the fifty claims, twenty-two were considered unsupported by scientific data, seventeen were classified as possibly supported, seven were well supported, and four were from companies that did not respond despite three requests. Claims that were supported by published data were significantly more likely to be rated as well supported (p < 0.001). All twelve claims that were supported purely by "data on file" at the company were considered to be poorly supported. CONCLUSIONS: Orthopaedic surgeons should interpret claims made in orthopaedic print advertisements with caution. Approximately half of the claims are not supported by enough data to be used in a clinical decision-making process.

Advertising↗

Chemotherapy and immunity in opportunistic parasitic infections in AIDS.

Parasitic diseases are endemic in parts of the tropics, but there is no convincing evidence that their prevalence or incidence is increasing due to the HIV epidemic. Available scientific data on parasitic infections in patients with the Acquired Immunodeficiency Syndrome (AIDS) suggests a predominance of Pneumocystis carinii, Toxoplasma gondii and Cryptosporidium spp. For reasons which are unclear, parasitic infections such as Plasmodium falciparum, Strongyloides stercoralis and Entamoeba histolytica, where cell-mediated immune responses are also thought to be significant, do not appear to be opportunists of importance. It is being increasingly recognized that chemotherapy for parasitic diseases has a host-dependent component, although scientific data on this subject remain scanty. The management of opportunistic parasitic infections in patients infected with HIV is dogged by failures and relapses, aptly illustrating the notion of the relationship between chemotherapy and the immune response. This review discusses the immunity and chemotherapy of opportunistic parasite infections in patients infected with the Human Immunodeficiency Virus (HIV).

AIDS-Related Opportunistic Infections↗

Ethics of psychosurgery.

The ethics of psychosurgery involve questions of moral philosophy and pragmatism in alleviating human suffering. The weighing of scientific data along with philosophical oughts and shoulds is required. The medical literature indicates definite efficacy for some kinds of limbic surgery, mainly cingulotomy and capsulotomy, in some kinds of conditions, namely major depression, pain and anxiety. The relative utility of these procedures given the severity of the illnesses and the safety of the procedures described is significant. Ethical and moral conflicts over altruism, autonomy and suffering require recognition before their due considerations (Kleinig 1985). The following recommendations emerge from these considerations: 1. No consideration of ethics in psychosurgery is complete without consideration of both the scientific data and moral conflicts. 2. The considerable efficacy and safety of cingulotomy and capsulotomy must be acknowledged. 3. Indications and contraindications do exist for selecting patients. Major psychiatric Axis I diagnoses of depression and anxiety are the indications. Personality disorders are not indications. 4. Peer review, unfettered consent and knowledge of the psychodynamics of severe illness are three ingredients necessary for wise decisions about performing limbic surgery. 5. The liberal advocation of autonomy without responsibility is an amoral, not liberating, point of view. 6. Politics should be denounced as the most serious ethical problem in medical decision making. Political intrusion into the scientific matters and the doctor-patient relationship has created ethical problems with psychosurgery and continues to do so today.

Caudate Nucleus↗

The legal aspects of treating and being treated by an individual infected with human immunodeficiency virus.

Since the first AIDS case was reported in 1981, the AIDS epidemic is spreading dramatically in the United States. In dealing with the prevention of HIV transmission, we need to carefully balance the protection of civil rights that may be devastated by the disclosure of HIV-infection and the protection of public health against HIV infection in the health care setting. Recognizing the need of guidances in this regard, the CDC has issued recommendations regarding the prevention of HIV transmission in the health care setting on the basis of scientific data. In order to assure the acceptance of CDC guidelines in the health care setting, Congress recently passed a law that requires every state to institute CDC guidelines or its equivalent within 1 year. It is hoped that this requirement will ensure that HIV infection control measures are uniform throughout the nations and help HCWs and patients know their legal rights and obligations. Most importantly, the law regulating HIV-infection control will from now on rely on scientific data rather than on the irrational fear of the general public.

Acquired Immunodeficiency Syndrome↗

Prevention of recurrent ischemic stroke.

Treatment after an ischemic stroke or transient ischemic attack (TIA) should target the presumed cause of the initial episode to facilitate focused prophylaxis. In the majority of ischemic strokes, degenerative large- and small-vessel disease is the cause. In these patients, attention to modifiable risk factors is an important priority. However, uncertainty and controversy remain regarding therapy, although issues are gradually being settled. There are now strong scientific data to support the use of carotid endarterectomy in patients with 70% to 99% stenosis and an ipsilateral TIA or nondisabling stroke. Aspirin is accepted as standard preventive therapy and should be used in all patients with a TIA or stroke, including those who undergo endarterectomy. Although the dose most commonly used in clinical trials is 1,300 mg/day, a daily dose of 325 mg is probably equally effective with less gastrotoxicity. Given present evidence, use of dipyridamole (Persantine) is not warranted. The role of ticlopidine hydrochloride (Ticlid) in stroke prophylaxis is not well defined. Its superiority over aspirin demonstrated in one study may make it the drug of first choice despite its expense and side effects. The efficacy of warfarin sodium (Coumadin, Panwarfin, Sofarin) or heparin in ischemic stroke caused by degenerative cerebrovascular disease is not supported by scientific data, but no prospective controlled studies have demonstrated that these agents are ineffective. Therefore, it seems prudent to reserve anticoagulant therapy for situations in which an ongoing thrombotic process is likely (eg, progressing stroke). Heparin therapy in the immediate post-TIA period is not warranted on the basis of current scientific evidence.

Anticoagulants↗

Cardiovascular toxicities of performance-enhancing substances in sports.

Athletes commonly use drugs and dietary supplements to improve athletic performance or to assist with weight loss. Some of these substances are obtainable by prescription or by illegal means; others are marketed as supplements, vitamins, or minerals. Nutritional supplements are protected from Food and Drug Administration regulation by the 1994 US Dietary Supplement Health and Education Act, and manufacturers are not required to demonstrate proof of efficacy or safety. Furthermore, the Food and Drug Administration lacks a regulatory body to evaluate such products for purity. Existing scientific data, which consist of case reports and clinical observations, describe serious cardiovascular adverse effects from use of performance-enhancing substances, including sudden death. Although mounting evidence led to the recent ban of ephedra (ma huang), other performance-enhancing substances continue to be used frequently at all levels, from elementary school children to professional athletes. Thus, although the potential for cardiovascular injury is great, few appropriately designed studies have been conducted to assess the benefits and risks of using performance-enhancing substances. We performed an exhaustive OVID MEDLINE search to Identify all existing scientific data, review articles, case reports, and clinical observations that address this subject. In this review, we examine the current evidence regarding cardiovascular risk for persons using anabolic-androgenic steroids including 2 synthetic substances, tetrahydrogestrinone and androstenedione (andro), stimulants such as ephedra, and nonsteroidal agents such as recombinant human erythropoietin, human growth hormone, creatine, and beta-hydroxy-beta-methylbutyrate.

Androstenedione↗

Industry-funded research and conflict of interest: an analysis of research sponsored by the tobacco industry through the Center for Indoor Air Research.

The Center for Indoor Air Research (CIAR) was created by three United States tobacco companies in 1988. Its stated mission is to fund high-quality, objective research related to indoor air, including studies of environmental tobacco smoke (ETS). Because CIAR is financed by the tobacco industry and funds research related to tobacco, it fosters an inherent conflict of interest. We consider whether this conflict of interest has affected the content, quality, or use of research funded by CIAR. We hypothesize that the tobacco industry might be using CIAR to develop scientific data to support its position that ETS is not harmful to health. CIAR funds two types of projects: "Peer-reviewed" projects are awarded after peer review by a group of scientists, whereas "special-reviewed" projects are awarded directly by tobacco industry executives. CIAR's special-reviewed projects are more likely than its peer-reviewed projects to be related to ETS, to support the tobacco industry position, and to be used by the industry to argue that smoking should not be regulated in public places. Our findings suggest that the tobacco industry is funding special-reviewed projects through CIAR to develop scientific data that it can use in legislative and legal settings. The industry may be financing peer-reviewed projects through CIAR to enhance its credibility, to provide good publicity, and to divert attention from ETS as an indoor air pollutant. CIAR's stated mission of funding high-quality, objective research has been compromised by conflict of interest, and at least some of CIAR's projects are being used to promote the tobacco industry's agenda.

Conflict of Interest↗

[Is 3'-deoxy-3'- [18F] fluorothymidine ([18F]-FLT) the next tracer for routine clinical PET after R [18F]-FDG?].

Positron emission tomography (PET) with [18F]-FDG is now firmly established as a clinical tool in oncology. Its applications are however limited in some indications, due to the lack of specificity of its uptake mechanism for tumors, or the low avidity of some cancer types such as prostate. Alternative tracers are thus being developed, in order to fill up this void. Proliferation as a biological target is particularly attractive in cancer imaging. From that perspective, fluorothymidine ([18F]-FLT or FLT) has generated a strong interest among the scientific community, especially since the radiosynthesis process has been improved and simplified, thus making possible to envision a routine use for the tracer. This article aims at summarizing the status of the current scientific data regarding FLT. The uptake mechanism of FLT is well known, relying on the thymidine kinase 1 (TK1) enzymatic activity, and thus on DNA synthesis. Preclinical studies have shown a clear relationship between tracer accumulation and level of tumor proliferation, even though DNA salvage pathwayss intervene in the process and may complicate the interpretation of the results. Several clinical studies suggest a good specificity for tumor, albeit with a lower sensitivity than with FDG. In all likelihood however, the future of FLT lies in the evaluation of antitumor response and possibly the pretherapeutic prognostic characterization, rather than in the diagnosis and staging of malignancies. Although the scientific data regarding this issue remain limited, initial results are encouraging. Further significant work remains to be done in order to fully assess the clinical performances of the tracer, on the one hand, and to determine its place relative to FDG and other emerging tracers, on the other hand. Until these studies are completed, FLT should be considered as a promising tracer, but remaining at an experimental stage of its development.

Animals↗

Eating and drinking in labor: the influence of caregiver advice on women's behavior.

BACKGROUND: Although there is much debate about eating and drinking during labor, little scientific data about its influence on the course of labor exist. In The Netherlands, most midwives and obstetricians allow women to eat and drink during normal labor. The objective of this study was to examine whether or not women were actively advised to eat and drink and if this advice affected eating and drinking behavior. METHODS: A randomly selected group of midwives and obstetricians from across The Netherlands identified 211 consecutive nulliparous women to participate in the study. In a questionnaire with open-ended questions, women were asked after their delivery whether or not they were advised about eating and drinking during labor, and if so, about the nature of this advice and what they had consumed. Data were analyzed at the Leyenburg Hospital in The Hague. RESULTS: Sixty-six percent of the women were not given advice about eating and drinking during labor. Women who were given advice usually followed it. In the total group, 37 percent of the women had intake other than water and of these, 75 percent ate solid food. After adjusting for other prognostic factors, the incidence of an instrumental delivery due to a nonprogressing second stage was lower in women with caloric intake (13% vs 24%, p = 0.04). CONCLUSION: The study design did not enable us to draw conclusions about the cause and effect between caloric intake and labor progress. Scientific data with respect to the giving of evidence-based advice about eating and drinking during labor are lacking. Should such advice become available, women are likely to follow it.

Drinking↗

Oral contraceptives and thrombosis. From risk estimates to health impact.

OBJECTIVE: The scientific debate on oral contraceptives (OCs) and thrombotic diseases continues unabated. The aim of this survey was to evaluate available scientific data on OCs and thrombotic diseases and to make tentative prescription recommendations of OCs to women with and without various thrombotic risk factors. CONSENSUS: In women 15-29 years old, venous thromboembolism is about twice as common as arterial complications. In women between 30 and 44 years, the number of arterial complications exceeds venous diseases by about 50%. The mortality from arterial diseases is 3.5 times higher than the number of deaths from venous diseases in women below 30 years, and 8.5 times higher in women 30-44 years old. A significant disability is more frequent in women suffering and surviving an arterial complication than in women with venous thromboembolism. Although many important scientific issues still have to be addressed, the available scientific data suggests a differential influence of OCs with second and third generation progestagens on the risk of venous and arterial diseases. OCs with second generation progestagens seem to confer a smaller increase in the risk of venous diseases and a higher increase in risk of arterial complications, compared with OCs containing third generation progestagens. The possible difference on the venous side seems to be smaller than primarily anticipated. RESULTS: Young women without any known risk factor for thrombotic diseases may use any low-dose OC. If OCs are prescribed to women with known risk factors for arterial thrombotic disease; e.g. smoking, diabetes, controlled hypertension, migraine without aura, family disposition of acute myocardial infarction (AMI) or thrombotic stroke, a low-dose pill with a third generation progestagen may have an advantage. If OCs are considered for women with risk factors for venous disease such as severe obesity, varicose veins, family history of VTE or with factor V Leiden mutation, a low-dose combined pill with a second generation progestagen may be preferable. In women above 30 years, OCs with third generation progestagens generally seem to confer less overall thrombotic morbidity, mortality and disability than OCs with second generation progestagens. These women should reconsider, however, the indication of combined OCs in the presence of significant risk factors of thrombotic diseases.

Adolescent↗

Anaesthetic practice for groin hernia repair--a nation-wide study in Denmark 1998-2003.

BACKGROUND: Recent scientific data suggest that local infiltration anaesthesia for inguinal hernia surgery may be preferable compared to general anaesthesia and regional anaesthesia, since it is cheaper and with less urinary morbidity. Regional anaesthesia may have specific side-effects and is without documented advantages on morbidity in this small operation. METHODS: To describe the use of the three anaesthetic techniques for elective open groin hernia surgery in Denmark from January 1st 1998 to December 31st 2003, based on the Danish Hernia Database collaboration. RESULTS: In a total of 57,505 elective open operations 63.6% were performed in general anaesthesia, 18.3% in regional anaesthesia and 18.1% in local anaesthesia. Regional anaesthesia was utilized with an increased rate in elderly and hospitalized patients. Outpatient surgery was most common with local infiltration anaesthesia. CONCLUSION: Use/choice of anaesthesia for groin hernia repair is not in accordance with recent scientific data. Use of spinal anaesthesia should be reduced and increased use of local anaesthesia is recommended to enhance recovery and reduce costs.

Adolescent↗

The human relevance of the renal tumor-inducing potential of d-limonene in male rats: implications for risk assessment.

The monoterpene d-limonene is a naturally occurring chemical which is the major component in oil of orange. Currently, d-limonene is widely used as a flavor and fragrance and is listed to be generally recognized as safe (GRAS) in food by the Food and Drug Administration (21 CFR 182.60 in the Code of Federal Regulations). Recently, however, d-limonene has been shown to cause a male rat-specific kidney toxicity referred to as hyaline droplet nephropathy. Furthermore, chronic exposure to d-limonene causes a significant incidence of renal tubular tumors exclusively in male rats. Although d-limonene is not carcinogenic in female rats or male and female mice given much higher dosages, the male rat-specific nephrocarcinogenicity of d-limonene may raise some concern regarding the safety of d-limonene for human consumption. A considerable body of scientific data has indicated that the renal toxicity of d-limonene results from the accumulation of a protein, alpha 2u-globulin, in male rat kidney proximal tuble lysosomes. This protein is synthesized exclusively by adult male rats. Other species, including humans, synthesize proteins that share significant homology with alpha 2u-globulin. However, none of these proteins, including the mouse equivalent of alpha 2u-globulin, can produce this toxicity, indicating a unique specificity for alpha 2u-globulin. With chronic exposure to d-limonene, the hyaline droplet nephropathy progresses and the kidney shows tubular cell necrosis, granular cast formation at the corticomedullary junction, and compensatory cell proliferation. Both d-limonene and cis-d-limonene-1,2-oxide (the major metabolite involved in this toxicity) are negative in in vitro mutagenicity screens. Therefore, the toxicity-related renal cell proliferation is believed to be integrally involved in the carcinogenicity of d-limonene as persistent elevations in renal cell proliferation may increase fixation of spontaneously altered DNA or serve to promote spontaneously initiated cells. The scientific data base demonstrates that the tumorigenic activity of d-limonene in male rats is not relevant to humans. The three major lines of evidence supporting the human safety of d-limonene are (1) the male rat specificity of the nephrotoxicity and carcinogenicity; (2) the pivotal role that alpha 2u-globulin plays in the toxicity, as evidenced by the complete lack of toxicity in other species despite the presence of structurally similar proteins; and (3) the lack of genotoxicity of both d-limonene and d-limonene-1,2-oxide, supporting the concept of a nongenotoxic mechanism, namely, sustained renal cell proliferation.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Protein purification: aspects of processes for pharmaceutical products.

The concept of purity is addressed for proteins as drugs. In addition to a short description of general techniques, emphasis is given to a discussion of special protein impurities and contaminants from the host cell of process additives. This includes the host homologue to the product and biologically active molecules and the quantitation of host cell proteins. Of special concern are closely related non functional proteins from the gene for the protein product itself. They pose the question of how a 'pure' protein can be defined, and to what extent potential heterogeneities caused by the purification method represent a risk. Most relevant are 'invisible' contaminants such as potential virus including the BSE agent. Critical aspects will be discussed of the current rationale for a strategy to arrive at safe biological products. The limitations of current virus enumeration methods are discussed in relation to technical limitations to prove the efficiency of virus removal steps. Another limitation is the nature of the protein product and its individual resistance to denaturing conditions in virus inactivation steps. This is amply demonstrated by the lack of methods for inactivation of the BSE agent maintaining the native state of proteins. As a general recommendation it is proposed to base risk assessment on scientific data and come to scientifically defined criteria of acceptance in both the global and national communities. This will facilitate bringing new biopharmaceuticals to the benefit of patients in the shortest period of time.

Animals↗