Antimicrobial susceptibility of bordetella pertussis (Part I)

Summary In this review of the literature data are collected from the more recent studies on the susceptibility ofBordetella pertussis to penicillins, cephalosporins, other beta-lactam antibiotics, aminoglycosides, tetracyclines, erythromycin, josamycin, co-trimoxazole and various other antibiotics. The methods of susceptibility testing ofB. pertussis are discussed and suggestions for standardization are made.

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Antibiotika-Empfindlichkeit von Bordetella pertussis

Zusammenfassung In dieser Literatur-Übersicht werden Daten aus neueren Arbeiten zusammengestellt über die Empfindlichkeit vonBordetella pertussis gegen Penicilline, Cephalosporine, andere Beta-Laktam-Antibiotika, Aminoglykoside, Tetrazykline, Erythromycin, Josamycin, Co-trimoxazol und verschiedene andere Antibiotika. Die Verfahren zur Empfindlichkeitstestung vonB. pertussis werden diskutiert, und es werden Vorschläge für eine Standardisierung gemacht.

     

Treatment of cancer and hematological malignancy in elderly people (Part II)

PURPOSE: Fifty percents of cancer arise in people older than 65-year-old. Most clinical trials in cancer treatment are limited in patients younger than 65-year-old. We review literature-describing particularity of cancer treatment in elderly patients. CURRENT KNOWLEDGE AND KEY POINTS: Therapeutic decisions should be based on an estimation of the patient's life expectancy, and risks and benefits should be weighted up accordingly. Geriatric oncology is made of a geriatric evaluation of patient and of knowledge of clinical trial about elderly patients. FUTURE PROSPECTS AND PROJECTS: We present in this issue the principle of geriatric evaluation and the results of recent clinical trial on elderly cancer patients.     

Retinoids as preventive and therapeutic anticancer agents (Part I)

Retinoids, the synthetic and natural analogs of vitamin A, frequently block the phenotypic expression of cancer in vitro; they also inhibit growth and induce differentiation in many animal and human malignant cell types. Only recently has it become possible to propose a unifying mechanism of retinoid action, which involves the protein kinase-C cascade system. This system may mediate retinoids' many diverse actions, including their effects on enzyme synthesis, membrane properties, growth factors, binding proteins, genomic and postgenomic expression, the extracellular matrix, and immunologic responses. Ongoing in vitro studies of retinoid structure-activity relationships, effects on oncogene expression, reversal of drug-resistance, and, especially, the protein kinase-C cascade system should help clarify the precise mechanism of their anticancer action. Many in vitro and in vivo assay systems are available for testing the 2000 + synthetic retinoids. These assays indicate specific drug sensitivities, which may help focus future clinical trials. In human cancer prevention, retinoids have been most effective for skin diseases, including actinic keratosis, keratoacanthoma, and basal cell carcinoma; however, nondermatologic premalignancies, such as oral leukoplakia, bronchial metaplasia, laryngeal papillomatosis, cervical dysplasia, myelodysplastic syndromes, and the urinary bladder, also respond to retinoid therapy. Significant therapeutic advances are also occurring with this class of drugs in refractory malignancies, including advanced cutaneous squamous and basal cell cancer, mycosis fungoides, and acute promyelocytic leukemia. Newer third-generation retinoids, such as the highly potent retinoidal benzoic acid derivatives, are demonstrating therapeutic indexes far higher than earlier-generation retinoids. Current in vitro testing is also demonstrating that retinoids have synergistic activity in combination with other agents (eg, biologic modifiers, hormones, and DNA synthesis inhibitors) and treatment modalities (eg, irradiation). Notwithstanding the progress already made with retinoids in human cancer, many in vitro questions remain, and clinical work is just beginning.     

Strongyloidosis. Part VII. Epidemiology and prevention (1)

The source of invasion of Strongyloides stercoralis and the routes of transmission strongyloidosis were presented. The survival, development and behavior forms parasitic and free-living generation of S. stercoralis in soil and host was also described.     

Strongyloidosis. Part VII. Epidemiology and prevention (2)

The formation of Strongyloides stercoralis infections in the tropical countries and in the temperate climatic zone, with special attention to the factors and the high risk groups, were described. The concurrent infections, prevention and control of strongyloidosis was also presented.     

耐甲氧西林金葡菌的临床分离率及其耐药性分析

目的 了解成都地区耐甲氧西林金黄色葡萄球菌（MRSA）耐药情况。方法 应用琼脂平皿二倍稀释法，测定万古霉素等12种抗菌药物对成都地区分离到的272株金黄色葡萄球菌（SA）的最低抑菌浓度（MIC）。结果 MRSA占临床分离SA的31.6%。MSSA除对青霉素，克拉霉素，氧氟沙星和环丙沙星部分耐药外，对其他所测抗菌药物均基本敏感，MRSA除对万古霉素敏感外，对其它抗生素均显示出不同程度的耐药。结论 MRSA对克拉霉素的耐药率最高（95.4%)，以下依次为环丙沙星（55.8%)，氧氟沙星（50.0%)，氨苄青霉素/舒巴坦（39.5%)。头孢唑啉以下依次为环丙沙星（55.8%)。氧氟沙星（50.0%)。氨苄青霉素/舒巴坦（39.5%)。头孢唑啉（36.1%)，头孢噻肟（30.3%)。利福平（27.9%)亚胺培南(17.5%)和阿米卡星（8.1%)。     

Central sleep apnoea and heart failure (Part II)

Central sleep apnoea (CSA) in congestive heart failure is sleep state dependent and occurs typically in stages I and II of non-REM sleep. The pre-requisites are hypocapnia and some prolongation of the circulation time. It is not certain whether abnormalities in after-discharge activity in the brainstem are also important. The presence of CSA in patients with left ventricular dysfunction is a poor prognostic sign and associated with a higher mortality in that group compared to age, sex and ejection fraction matched patients with congestive cardiac failure alone. It is reasonable to speculate that the CSA causes an increase in sympathetic nervous system activity which would maintain afterload at a high level or tend to increase it with time. The application of a high afterload to an impaired left ventricle leads over time to a further reduction in ejection fraction. From other studies, particularly ACE inhibitor studies, it is known that ejection fraction and prognosis are almost linearly related. It could therefore be said that once CSA has developed it may lead to a vicious circle of increasing afterload and further reduction in ejection fraction, causing worsening CSA and further increases in afterload. A number of treatments have been shown to be of benefit: supplemental nocturnal oxygen therapy, acetazolamide and nasal CPAP therapy have all been shown to reduce CSA. In addition nasal continuous positive airways pressure (CPAP) has been shown by two groups in Canada to also improve ejection fraction. The beneficial effects on ejection fraction in particular, persist after the treatment has been withdrawn, which suggests either remodelling of the left ventricular musculature or a resetting of the baseline sympathetic nervous system activity. The impressive increase in ejection fraction due to three months nasal CPAP therapy in one study (an average 35% increase) is both dramatic and exciting for the future. It is reasonable to expect improvement in prognosis for patients with CCF whose ejection fraction rises with CPAP treatment. Finally, only a limited number of studies have been published. Unfortunately the impressive results from Canada have not yet been reproduced in other centres around the world.     

Hepatotoxicity of antimicrobial agents

Antimicrobial agents are a common and important cause of hepatotoxicity. As a class, the antimicrobials contain many and varied structures, leading to a wide clinical spectrum of hepatotoxicity. Minor liver injury, manifest only as liver enzyme elevations, is common with some antimicrobials. Clinically significant injury is unusual but can adopt almost any form. Classical acute hepatocellular, cholestatic, or mixed reactions are most often seen. Other forms of hepatotoxicity including granulomatous reactions, steatosis, chronic hepatitis, and cirrhosis have also been described. Generally, antimicrobial-associated hepatotoxicity is mild and self-limited; most cases resolve after withdrawal of the offending medication. Occasionally, however, liver injury presents as a fulminant life-threatening condition or may develop into a chronic illness with significant morbidity. This article presents a summary of reported hepatotoxicity associated with the major classes of antimicrobials and, where possible, identifies potential risk factors and management strategies to assist clinical practice.     

Current and new antimicrobial agents

Background

Infections may complicate cardiovascular surgery or may require surgery as an adjunct to successful treatment. Staphylococci, which are among the major pathogenic bacteria causing such infections, can be resistant to many of the older antibiotics.

Methods

The properties of several newer antimicrobial agents, recently approved or still investigational, were reviewed, with an emphasis on in vitro activities against staphylococci.

Results

The 2 approved agents, linezolid and quinupristin-dalfopristin, and several investigational agents being developed demonstrate in vitro antimicrobial activity against staphylococci. Three of these agents, daptomycin, which was approved by the US Food and Drug Administration in September 2003, and oritavancin and dalbavancin, which are in advanced stages of clinical development, are discussed.

Conclusions

Although clinical studies are required, the in vitro anti-staphylococcal activities of several agents suggest that these antimicrobial agents might be useful options for some infections in patients who are intolerant of older antibiotics or who are infected with organisms that are resistant to older agents.     

Dyslipidemia and abdominal obesity: therapeutic approaches (Part II)

Lifestyle changes form the basis of the therapeutic management of dyslipidemia associated with abdominal obesity and other risk factors associated with an excess of visceral adipose tissue. The use of lipid-lowering agents is justified if the therapeutic objectives are not attained by lifestyle changes alone. New therapeutic approaches are aimed directly at the excess visceral adipose tissue, and the CB1 receptor blockers are particularly promising for improving the overall lipid profile for patients with abdominal obesity.