68 research outputs found

    Epidemiology of Clostridium difficile in infants in Oxfordshire, UK: Risk factors for colonization and carriage, and genetic overlap with regional C. difficile infection strains

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    Background: Approximately 30-40% of children <1 year of age are Clostridium difficile colonized, and may represent a reservoir for adult C. difficile infections (CDI). Risk factors for colonization with toxigenic versus non-toxigenic C. difficile strains and longitudinal acquisition dynamics in infants remain incompletely characterized. Methods: Predominantly healthy infants (≤2 years) were recruited in Oxfordshire, UK, and provided ≥1 fecal samples. Independent risk factors for toxigenic/non-toxigenic C. difficile colonization and acquisition were identified using multivariable regression. Infant C. difficile isolates were whole-genome sequenced to assay genetic diversity and prevalence of toxin-associated genes, and compared with sequenced strains from Oxfordshire CDI cases. Results: 338/365 enrolled infants provided 1332 fecal samples, representing 158 C. difficile colonization or carriage episodes (107[68%] toxigenic). Initial colonization was associated with age, and reduced with breastfeeding but increased with pet dogs. Acquisition was associated with older age, Caesarean delivery, and diarrhea. Breastfeeding and pre-existing C. difficile colonization reduced acquisition risk. Overall 13% of CDI C. difficile strains were genetically related to infant strains. 29(18%) infant C. difficile sequences were consistent with recent direct/indirect transmission to/from Oxfordshire CDI cases (≤2 single nucleotide variants [SNVs]); 79(50%) shared a common origin with an Oxfordshire CDI case within the last ~5 years (0-10 SNVs). The hypervirulent, epidemic ST1/ribotype 027 remained notably absent in infants in this large study, as did other lineages such as STs 10/44 (ribotype 015); the most common strain in infants was ST2 (ribotype 020/014)(22%). Conclusions: In predominantly healthy infants without significant healthcare exposure C. difficile colonization and acquisition reflect environmental exposures, with pet dogs identified as a novel risk factor. Genetic overlap between some infant strains and those isolated from CDI cases suggest common community reservoirs of these C. difficile lineages, contrasting with those lineages found only in CDI cases, and therefore more consistent with healthcare-associated spread

    Glucosamine and chondroitin sulfate supplementation to treat symptomatic disc degeneration: Biochemical rationale and case report

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    BACKGROUND: Glucosamine and chondroitin sulfate preparations are widely used as food supplements against osteoarthritis, but critics are skeptical about their efficacy, because of the lack of convincing clinical trials and a reasonable scientific rationale for the use of these nutraceuticals. Most trials were on osteoarthritis of the knee, while virtually no documentation exists on spinal disc degeneration. The purpose of this article is to highlight the potential of these food additives against cartilage degeneration in general, and against symptomatic spinal disc degeneration in particular, as is illustrated by a case report. The water content of the intervertebral disc is a reliable measure of its degeneration/ regeneration status, and can be objectively determined by Magnetic Resonance Imaging (MRI) signals. CASE PRESENTATION: Oral intake of glucosamine and chondroitin sulfate for two years associated with disk recovery (brightening of MRI signal) in a case of symptomatic spinal disc degeneration. We provide a biochemical explanation for the possible efficacy of these nutraceuticals. They are bioavailable to cartilage chondrocytes, may stimulate the biosynthesis and inhibit the breakdown of their extracellular matrix proteoglycans. CONCLUSION: The case suggests that long-term glucosamine and chondroitin sulfate intake may counteract symptomatic spinal disc degeneration, particularly at an early stage. However, definite proof requires well-conducted clinical trials with these food supplements, in which disc de-/regeneration can be objectively determined by MRI. A number of biochemical reasons (that mechanistically need to be further resolved) explain why these agents may have cartilage structure- and symptom-modifying effects, suggesting their therapeutic efficacy against osteoarthritis in general

    Exercise and functional foods

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    Appropriate nutrition is an essential prerequisite for effective improvement of athletic performance, conditioning, recovery from fatigue after exercise, and avoidance of injury. Nutritional supplements containing carbohydrates, proteins, vitamins, and minerals have been widely used in various sporting fields to provide a boost to the recommended daily allowance. In addition, several natural food components have been found to show physiological effects, and some of them are considered to be useful for promoting exercise performance or for prevention of injury. However, these foods should only be used when there is clear scientific evidence and with understanding of the physiological changes caused by exercise. This article describes various "functional foods" that have been reported to be effective for improving exercise performance or health promotion, along with the relevant physiological changes that occur during exercise

    Effective Programs in Elementary Mathematics: A Best-Evidence Synthesis

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    Understanding rare and common diseases in the context of human evolution

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    The first cataract surgeons in Latin America: 1611&ndash;1830

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    Christopher T Leffler,1 Ricardo D Wainsztein2 1Department of Ophthalmology, Virginia Commonwealth University, Richmond, VA, USA; 2Instituto de la Visi&oacute;n, Buenos Aires, Argentina Abstract: We strove to identify the earliest cataract surgeons in Latin America. Probably by 1611, the Genovese oculist Francisco Drago was couching cataracts in Mexico City. The surgeon Melchor V&aacute;squez de Valenzuela probably performed cataract couching in Lima by 1697. Juan Per&eacute; of France demonstrated cataract couching in Veracruz and Mexico City between 1779 and 1784. Juan Ablanedo of Spain performed couching in Veracruz in 1791. Cataract extraction might have been performed in Havana and Caracas by 1793 and in Mexico by 1797. The earliest contemporaneously documented cataract extractions in Latin America were performed in Guatemala City by Narciso Esparragosa in 1797. In addition to Esparragosa, surgeons born in the New World who established the academic teaching of cataract surgery included Jos&eacute; Miguel Mu&ntilde;oz in Mexico and Jos&eacute; Mar&iacute;a Vargas in Caracas. Although cataract surgery came quite early to Latin America, its availability was initially inconsistent and limited. Keywords: cataract surgery, couching, history of medicin

    The Analysis of Variability

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    The early history of glaucoma: the glaucous eye&nbsp;(800 BC to 1050 AD)

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    Christopher T Leffler,1 Stephen G Schwartz,2 Tamer M Hadi,3 Ali Salman,1 Vivek Vasuki1 1Department of Ophthalmology, Virginia Commonwealth University, Richmond, VA, USA; 2Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Naples, FL, USA; 3Graduate School of Medicine, University of Tennessee Medical Center at Knoxville, TN, USA Abstract: To the ancient Greeks, glaukos occasionally described diseased eyes, but more typically described healthy irides, which were glaucous (light blue, gray, or green). During the Hippocratic period, a pathologic glaukos pupil indicated a media opacity that was not dark. Although not emphasized by present-day ophthalmologists, the pupil in acute angle closure may appear somewhat green, as the mid-dilated pupil exposes the cataractous lens. The ancient Greeks would probably have described a (normal) green iris or (diseased) green pupil as glaukos. During the early Common Era, eye pain, a glaucous hue, pupil irregularities, and absence of light perception indicated a poor prognosis with couching. Galen associated the glaucous hue with a large, anterior, or hard crystalline lens. Medieval Arabic authors translated glaukos as zarqaa, which also commonly described light irides. Ibn Sina (otherwise known as Avicenna) wrote that the zarqaa hue could occur due to anterior prominence of the lens and could occur in an acquired manner. The disease defined by the glaucous pupil in antiquity is ultimately indeterminate, as the complete syndrome of acute angle closure was not described. Nonetheless, it is intriguing that the glaucous pupil connoted a poor prognosis, and came to be associated with a large, anterior, or hard crystalline lens. Keywords: glaucoma, history of ophthalmology, couchin

    Prevalence and factors predictive of intraocular fungal infection in patients with fungemia at an academic urban tertiary care center

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    Elena Geraymovych,1 Joseph H Conduff,2 Puneet S Braich,3 Christopher T Leffler,3 Vikram S Brar3 1Department of Ophthalmology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 2Virginia Commonwealth University School of Medicine, 3Department of Ophthalmology, Virginia Commonwealth University, Richmond, VA, USA Objective: To report the prevalence and to identify factors predictive of intraocular infection in patients with fungemia receiving prophylactic antifungal therapy. Methods: A retrospective review of patients who received prophylactic antifungal therapy and a dilated fundus examination at an academic urban tertiary care center from 2000 to 2007. Basic demographic information, fungal species grown, antifungal agent(s) used, number of positive blood culture specimens, visual acuity, visual symptoms, and known risks of disseminated candidiasis were noted. Logistic regression analysis was used to determine the factors significantly associated with intraocular fungal infection. Results: A total of 132 patients with positive fungemia culture were requested to have ophthalmology consults. The prevalence of ocular infection was 6.9% (N=9). All nine patients were infected with Candida species. Undergoing gastrointestinal (GI) surgery within the prior 6&nbsp;months was significantly related to developing intraocular infection, with an odds ratio of 18.5 (95% confidence interval, 15.1&ndash;24.3; P=0.002). Having &ge;3 positive fungal blood cultures was also a significant risk factor, with an odds ratio of 2.6 (95% confidence interval, 1.8&ndash;3.7; P=0.03). Among 40 patients having GI surgery, eight (20.0%) had intraocular fungal disease, compared with one of 92 patients (1.1%) not having GI surgery. Among 125 patients with a negative baseline examination result, two of 32 patients (6.3%), who had recent GI surgery, subsequently developed fungal ocular disease, compared with 0 of 93 patients (0%), who did not have recent GI surgery. Conclusion: Recent GI surgery and higher numbers of positive fungal blood culture specimens may be predictive of candida ocular infections. Normal baseline fundoscopy examination results in patients with such risks may require repeat evaluations to detect delayed manifestations. Keywords: fungal chorioretinitis, fungal endophthalmitis, risks factors for intraocular fungal infection, risks of gasterointestinal surger
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