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By R. Garik. Linfield College.

Quantitative chromatography (HPLC or GC) is one of the most popular and effective means of quantifying compounds in crude drugs and their preparations generic levitra plus 400 mg amex erectile dysfunction treatment vancouver. This may be combined with mass spectrometry to obtain more detailed information on the 23 identity of the constituents analyzed generic levitra plus 400 mg without prescription erectile dysfunction symptoms age. Several other analytical methods may be used to 24 quantitate herbal constituents including separation and weighing of active constituents, titration, physical tests, quantitative spectroscopy, radioimmunoassay, enzyme- 25 immunoassay and biological assays based on an appropriate therapeutic activity. The analytical basis of the assay of a particular herbal product depends on the type of 9 preparation and the state of knowledge about its active constituents. Where the therapeutically relevant constituents are known, the product is standardized to that 9 particular substance. Alternatively, standardization may be based on a group of related constituents, all of which are known to contribute to therapeutic efficacy. An example here would be the measurement of total hydroxyanthracene glycosides in senna (Cassia angustifolia or acutifolia) fruit, as these compounds collectively provide the laxative effects of the botanical. Alternatively, TLC, HPLC or gas- liquid chromatography (GLC) profiles are matched for repeatability. Single or multiple markers are used for internal batch control, to ensure that the concentration and ratio of components in an herbal mixture are present at reproducible levels in raw materials, 21 manufacturing intermediates and the final dosage forms. The purity of herbal products is an important consideration, as the adverse effects of botanical products have often been associated with substitution or contamination of the declared ingredients with a toxic substance such as a more toxic botanical, a poisonous 26 18,26 metal or a potent non-herbal drug substance (Table 3 ). Simple visual examination will detect the presence of foreign material such as molds, insects and other animal contamination. Ash tests described in pharmacopeias give an indication of inorganic impurities present as contaminants in herbal specimens. The determination of the moisture content of crude drugs is particularly important for most plant materials, since these are susceptible to degradation or deterioration in the presence of excessive moisture. The contamination of herbal material with potentially 26 pathogenic micro-organisms and microbial toxins provides a further hazard. Standards for acceptable levels of microbial contamination in pharmaceutical preparations cannot always be attained with herbal products. Therefore, manufacturers will generally ensure Botanicals—quality, efficacy, safety and drug interactions 19 that, for crude drugs to be taken internally, the limits for bacterial and mold 24 contamination as applied to foodstuffs are adhered to unless the products are parenteral phytotherapeutic Table 3 Potential contaminants of herbal products. Adapted from references 18 and 26 Type of Examples contaminant Toxic botanicals Atropa belladonna, Digitalis, Colchicum, Rauwolfia serpentina, pyrrolizidine- containing plants Micro- Staphylococcus aureus, Escherichia coli, Salmonella, Shigella, Pseudomonas organisms aeruginosa Microbial toxins bacterial endotoxins, aflatoxins Pesticides chlorinated pesticides (e. DDT, DDE, HCH isomers, HCB, aldrin, dieldrin, heptachlor), organic phosphates, carbamate insecticides and herbicides, dithiocarbamate fungicides, triazin herbicides Fumigation ethylene oxide, methyl bromide, phosphine agents Radioactivity Cs-134, Cs-137, Ru-103, I-131, Sr-90 Metals lead, cadmium, mercury, arsenic Synthetic drugs analgesic and anti-inflammatory agents, corticosteroids, hydrochlorothiazide, diazepam Animal drugs thyroid hormones 26 preparations. Pesticides and fumigation agents can also be tested by chromatographic 24,26,27 and other means. Methods can also be applied to determine the presence of residual 18,26 levels of radioactivity and toxic metals. EVIDENCE FOR EFFICACY OF BOTANICAL PRODUCTS ACTING ON THE NERVOUS SYSTEM The numerous botanical products available to consumers include several that have become popular for their potential use in conditions with a neurological basis. Chinese or Korean ginseng (Panax ginseng) is also 6 reputed to improve cognitive function. Jensen cited poor patentability, uncertainty about active compounds and unknown pharmacodynamics (i. However, human studies of varying levels of reliability have been performed on these herbs and reviews and meta- Complementary therapies in neurology 20 analyses are available. The scope and value of these compilations is often compromised 28,29 by the limited quality of some of the studies available. Tables 4 and 5 outline guidelines provided by European and US authorities on the evaluation of published data relating to the safety and efficacy of botanical products. Meta-analyses of randomized, controlled trials are suggested to be the best level of evidence. This supports earlier reviews showing clear evidence in favor of overall improvements in cognitive function and 32 symptoms such as forgetfulness and poor concentration. One meta-analysis cautiously concluded that ginkgo was superior to placebo in individuals with cerebral 33 34 insufficiency. By contrast, a recent study reported no improvement in memory or cognitive function in healthy, elderly people receiving a standard dose of ginkgo for 6 weeks. However, one contributing factor here may be that the treatment period was shorter than those used in earlier studies. Based on FDA May 1998: Guidance for Industry: Providing Clinical Evidence of Effectiveness for Human Drugs and Biological Products and references 28 and 29 Multiple studies conducted by different investigators and/or independent literature reports where the findings are consistent A high level of detail in the published reports, including clear and adequate descriptions of statistical plans, analytical methods and study endpoints, and a full accounting of all enrolled patients Appropriate endpoints that can be objectively assessed and are not dependent on investigator judgment (e. Definitions of the levels of evidence of the safe and effective use of an herbal medicinal product. Based on the US Agency for Health Care Policy and Research and the WHO and references 28 and 29 Level Type of evidence Ia Evidence obtained from meta-analysis of randomized controlled trials Ib Evidence obtained from at least one randomized controlled trial IIa Evidence obtained from at least one well-randomization designed controlled study without IIb Evidence obtained from at least one other type of well-designed quasi-experimental study III Evidence obtained from well-designed non-experimental descriptive studies, such as comparative studies, correlation studies and case-control studies IV Evidence obtained from expert committee reports or opinions and/or clinical experience of respected authorities 35 A 2002 Cochrane review, while recognizing the need for more clinical trials, concluded that there was promising evidence of improvement in cognition and function associated with ginkgo, with no excess side-effects compared to placebo. A systematic review of the relatively small number of placebo-controlled clinical trials 45 of kava for anxiety symptoms found a significant beneficial effect of the herb. The therapeutic potential of kava for anxiety, including its putative mode of action, is the 46 subject of a recent review. However, there have been some recent safety concerns with 46 this botanical that may limit its use (see later).

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Despite its problems order 400mg levitra plus free shipping hypothyroidism causes erectile dysfunction, evidence-based surgery does not aim to exclude the individual clinical experiences of surgeons order levitra plus 400mg with mastercard erectile dysfunction drugs cost comparison. The next sections discuss evidence-based surgery from the perspective of an active clinical researcher attempting to design and conduct a study — not from the perspective of a surgeon trying to understand the literature. After a discussion of trial formats and the clinical outcomes that can be measured, fallacies in this approach will be evaluated in detail. The same surgical procedure (for example, a lumbar discectomy) may be viewed from the perspective of the patient, the surgeon, or society. The value of surgery and the outcome may be viewed completely differently by these three involved parties. The patient may view the same surgery as a complete failure if his or her back pain is not resolved (despite leg pain improvement), even though total resolution was not an expectation of the procedure. Society as a whole may view the surgery as not worth funding if patients do not commonly return to work, even though this expectation may be far different from expectations of the medical community. These differing viewpoints naturally lead on occasion to opposing philosophies as to the worth or overall benefit of a particular medical or surgical approach. Examples of such processes include cellular distur- bances consistent with the onset of disease processes such as spinal osteoarthritis and cerebrovascular accidents. Although surgical research has focused on pathology since the 19th century, largely following the Virchow tradition,9,10 pathology is not linearly associated with the final clinical outcomes noticed by patients and surgeons. It is therefore necessary to consider pathological findings with other outcome measures such as impairment. Pathological measures are often primary methods (separate from the symptoms associated with the primary disease) for understanding whether a treatment is © 2005 by CRC Press LLC working. For example, measurement of the size of a brain tumor on MRI scans can form a primary data source with which to compare various chemotherapy treatment regimens. In spine studies, radiographic fusion is often used as a surrogate marker for success of a fusion procedure, even though this marker does not appear to correlate with patient outcomes in most other respects. Clearly, the use of pathological measures may be an important basis to decide on treatment efficacy at a basic level, but these measures likely require supplementation with other types of outcomes to decide whether a treatment on the whole is worthwhile at patient level. Active pathology may result in some type of impairment, but not all impairments are associated with active pathology (e. Impairments can usually be objec- tively specified by an observer such as a physician or surgeon, and are classified in a standard text, the American Medical Association Guide to Impairment. For example, a limitation in shoulder range of motion secondary to a cerebral vascular accident may greatly affect the life of an active patient and be of little importance to a sedentary elderly patient. We will focus our discussion on the disablement model developed by Saad Nagi, a sociolo- gist,12 the International Classification of Impairments, Disabilities and Handicaps (ICIDH-1),13 and its current revision, the International Classification of Functioning, Disability and Health (ICF). It may not constitute a disability for some occupations (manual laborer) but would produce complete disability for others (concert pianist, surgeon). This is a fundamental distinction of critical importance to scholarly discussion and research related to disability phenomena. We will not review the ICIDH-1 classification except to note that in principle this original system was designed as a model for coding and manipulating data on the consequences of health conditions. Part 1 covers functioning and disability including body functions, structures, activities, and participation. Each component consists of various domains and, within each domain, categories that are the units of classification. This view fails to recognize that disablement is more often a dynamic process that can fluctuate in breadth and severity across the life course; it is anything but static or unidirectional. More recent disablement formulations and elaborations of earlier models have explicitly acknowledged that the disablement process is far more dynamic. In these newer concepts, a given disablement process may lead to further downward spiraling consequences. Pope and Tarlov15 use secondary conditions to describe any type of secondary consequence of a primary disabling condition. Commonly reported sec- ondary conditions include pressure sores, contractures, depression, and urinary tract infections, but it should be understood that they can be pathologies, impairments, functional limitations, or additional disabilities. Longitudinal analytic techniques now exist to incorporate secondary conditions into research models and are beginning to be used in disablement epidemiologic investigations. Because patient satisfaction is a multidimensional concept, it is important to start by understanding its multiple definitions. Patient satisfaction is a complex concept that may incorporate sociode- mographic, cognitive, and affective components. Although many theories for patient satisfaction have been proposed, few have been extensively tested and validated in different health care settings. Moreover, few studies have been conducted to explain associations between patient satisfaction and patient characteristics or subsequent patient behaviors. Although theories of patient satisfaction are difficult to categorize in an organized and easily comprehensible fashion, one may group these theories into intrapatient comparisons (disconfirmation theory) and differences between individual patients and health care providers (attribution theory) or other patients (equity theory). Intrapatient comparison theories explain the satisfaction phenomenon by a match between patient expectations and perceptions of medical care. Differences between what is expected and what is perceived to occur will contribute to patient satisfaction or dissatisfaction.

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Several weeks after completing supplemental intravenous potassium and magne- induction chemotherapy generic levitra plus 400 mg online erectile dysfunction drugs bangladesh, he developed profound sium to replace electrolytes lost in the urine to am- neutropenia (absolute granulocyte count of less photericin B–induced renal tubular acidosis buy levitra plus 400mg line erectile dysfunction adderall xr. The patient tericin B was discontinued, and a lipid formulation received granulocyte-monocyte colony stimulating of amphotericin B was substituted; renal function factor (GM-CSF), but neutropenia persisted; he stabilized and then improved slightly. After 4 weeks then had a temperature elevation to 103°F of profound neutropenia, the patient was noted to (39. Vancomycin However, the patient once again developed high empirical coverage was added 2 days later as high fever and appeared ill. A computed fevers continued, and 3 days later the patient began tomographic scan of the abdomen revealed multiple empirical therapy with amphotericin B for possible small low-density lesions in the liver and spleen. With the addition of amphotericin B, Antifungal therapy with a lipid formulation of am- the patient appeared to improve clinically, with less photericin B was continued. The patient had a 52 Antifungal Drugs 605 Case Study Chronic Disseminated Candidiasis stormy course requiring 4 additional weeks of anti- nia. A computed tomography showed resolution of hepatic new elevation in serum transaminases provided the and splenic abscesses. He was discharged home af- clue that led to abdominal imaging and the detec- ter a 2- month hospitalization. The diag- nosis of chronic disseminated candidiasis is often ANSWER: Chronic disseminated candidiasis (he- not confirmed by blood culture; the yield of blood patosplenic candidiasis) occurs in patients with pro- cultures in the detection of candidemia is poor, with found neutropenia. This patient was appropriately up to 50% of blood cultures falsely negative in this treated for possible fungal sepsis when antibacterial setting. Chronic disseminated candidiasis in neu- therapy failed to resolve fever in the setting of neu- tropenic leukemia patients is a life-threatening in- tropenia. Although some of these diseases are endemic to the United States Amebiasis and Balantidial Dysentery or can be found in migrant workers or individuals re- turning from an endemic area, many other such infec- The protozoan Entamoeba histolytica causes amebiasis, tions are rarely seen in the United States. However, an infection that is endemic in parts of the United physicians should be aware of these diseases and seek States. The parasite can be present in the host as either advice from those experienced in their diagnosis and an encysted or a trophozoite form. The latter symptom occurs assumed or known modes of action of a number of the after invasion of the intestinal mucosa by the actively agents. The treatment of malaria is discussed at the end motile and phagocytic trophozoite form of the proto- of this chapter. More recently, it has been The flagellate leishmania is transmitted to humans by recognized that infection can be transmitted by sexual the bite of the female sandfly of the genus Phlebotomus. Three principal diseases result from infection with Balantidium coli is the largest of the protozoans that Leishmania spp. The trophozoite causes superficial necrosis or leishmaniasis, the protozoan parasitizes the reticuloen- deep ulceration in the mucosa and submucosa of the dothelial cells, and this results in an enlargement of the large intestine. Otherwise healthy persons commonly lymph nodes, liver, and spleen; the spleen can become exhibit nausea, vomiting, abdominal pain, and diarrhea, massive. Cutaneous leishmaniasis remains localized to whereas debilitated or nutritionally stressed patients the site of inoculation, where it forms a raised disfiguring may develop severe dysentery. It is characterized by ulceration of the mucous membranes of the nose, mouth, and phar- Trichomoniasis and Giardiasis ynx; some disfiguring skin involvement also is possible. Trichomoniasis is a genital infection produced by the African trypanosomiasis follows the bite of Glos- protozoan Trichomonas vaginalis. Infections frequently sina, a tsetse fly infected with the protozoan Trypano- are asymptomatic in the male, whereas in the female soma brucei. The ensuing illness (sleeping sickness)is vaginitis characterized by a frothy pale yellow discharge initially characterized by the hemolymphatic stage of is common. This latter more 608 VI CHEMOTHERAPY serious stage requires different, more potentially toxic excreted by the kidneys, although small amounts can be drugs than does the hemolymphatic stage. Metronidazole is active against intestinal quite different from African trypanosomiasis in its clin- and extraintestinal cysts and trophozoites. Metronidazole Metronidazole (Flagyl, Metrogel) exerts activity against Adverse Effects most anaerobic bacteria and several protozoa. The drug The most frequently observed adverse reactions to freely penetrates protozoal and bacterial cells but not metronidazole include nausea, vomiting, cramps, diar- mammalian cells. The enzyme, pyruvate-ferredoxin oxidoreduc- paresthesias, peripheral neuropathy, encephalopathy, tase, found only in anaerobic organisms, reduces and neutropenia have been reported. Reduced zole is a weak inhibitor of alcohol dehydrogenase, alco- metronidazole disrupts replication and transcription hol ingestion should be avoided during treatment. Metronidazole interferes with the metabolism of warfarin and may po- Antimicrobial Spectrum tentiate its anticoagulant activity.

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