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Sokolova O.I.,Saint Petersburg State University | Demyanov A.V.,Pure Research | Bowers L.C.,Tulane National Primate Research Center | Didier E.S.,Tulane National Primate Research Center | And 3 more authors.
Journal of Clinical Microbiology | Year: 2011

Microsporidia were identified in stool specimens by histochemistry and PCR of 30 (18.9%) of 159 HIVinfected patients presenting to the S. P. Botkin Memorial Clinical Hospital of Infectious Diseases, St. Petersburg, Russia. The higher prevalence of Encephalitozoon intestinalis, in 21 (12.8%) patients, than of Enterocytozoon bieneusi, in 2 patients (1.2%), was unexpected. Encephalitozoon cuniculi was detected in three patients: one with strain I and two with strain II. Encephalitozoon hellem was detected in one patient, and two patients were identified as being infected by Microsporidium species. One patient was infected with both E. intestinalis and E. cuniculi. In two patients, the microsporidian species were not identifiable. No statistically significant differences in gender, age, and stage of AIDS were observed between the microsporidian-positive and -negative HIV-infected patients. HIV-infected patients diagnosed with microsporidian infection, however, were significantly more likely to exhibit ≤100 CD4+ T cells/μl blood (20/30 patients [67%]; odds ratio [OR], 3.150; 95% confidence interval [CI95], 1.280 to 7.750; P = 0.0116) and weight loss of >10% of the baseline (19/30 patients [63%]; odds ratio, 2.995; CI95, 1.100 to 8.158; P = 0.0352) than HIV-infected patients not diagnosed with microsporidian infection. In summary, this is the first report describing the diagnosis of microsporidian infection of HIV-infected patients in Russia and the first detection of E. cuniculi strain II in a human. Copyright © 2011, American Society for Microbiology. All Rights Reserved. Source

Barrett M.P.,University of Glasgow | Gemmell C.G.,University of Strathclyde | Suckling C.J.,Pure Research
Pharmacology and Therapeutics | Year: 2013

Minor groove binders are small molecules that form strong complexes with the minor groove of DNA. There are several structural types of which distamycin and netropsin analogues, oligoamides built from heterocyclic and aromatic amino acids, and bis-amidines separated by aromatic and heterocyclic rings are of particular pharmaceutical interest. These molecules have helical topology that approximately matches the curvature of DNA in the minor groove. Depending upon the precise structure of the minor groove binder, selectivity can be obtained with respect to the DNA base sequence to which the compound binds. Minor groove binders have found substantial applications in anti-cancer therapy but their significance in anti-infective therapy has also been significant and is growing. For example, compounds of the bis-amidine class have been notable contributors to antiparasitic therapy for many years with examples such as berenil and pentamidine being well-known. A recent growth area has been inreased sophistication in the oligoamide class. High sequence selectivity is now possible and compounds with distinct antibacterial, antifungal, antiviral, and antiparasitic activity have all been identified. Importantly, the structures of the most active compounds attacking the various infective organisms differ significantly but not necessarily predictively. This poses interesting questions of mechanism of action with many different targets involved in DNA processing being candidates. Access of compounds to specific cell types also plays a role and in some cases, can be decisive. Prospects for a range of selective therapeutic agents from this class of compounds are higher now than for some considerable time. © 2013 Elsevier Inc. All rights reserved. Source

Lo C.Y.,Pure Research
Physics Essays | Year: 2010

An overdue critical analysis of Einstein's general relativity is provided. For the dynamic case, the Einstein equation is invalid since it is impossible to have a physical solution. For the static case, Einstein's covariance principle has been proven invalid. This error comes from Einstein's theory of measurement which adapts the notion of distance in Riemannian geometry as if it were valid in physics. It is shown that such a theory was not used in Einstein's predictions and its supporting arguments are actually based on invalid applications of special relativity. Nevertheless, Einstein's equivalence principle plays a crucial role in rectifying the shortcomings of his theory of measurement. Moreover, the Maxwell-Newton approximation for massive sources is proven to be independently valid for the dynamic cases. Then, to explain the binary pulsar experiments, the Einstein equation needs to be modified with an additional source of the gravitational stress-energy tensor with a different coupling sign. After E=m c2 is shown to be only conditionally valid, the charge-mass interaction is discovered, and its existence is experimentally verified. Thus, the unification of gravitation and electromagnetism is necessary. This new force explains the characteristics of NASA's Pioneer anomaly. Moreover, since a photon must include gravitational energy, particle physics cannot be fully understood without taking gravity into consideration. © 2010 Physics Essays Publication. Source

It is pointed out that all the gauge theories in physics actually are not gauge invariant. Calculation of the deflection angle to the second order shows that general relativity is also not gauge invariant since the shortest distance from the Sun center is different for each gauge. Further, different "de Sitter" precession formulas of the first order are obtained for different gauges. Thus, Einstein's covariance principle is intrinsically invalid. This invalidity would imply also that Einstein's theory of measurement is invalid, since his covariance principle is the remedy for his theory of measurement. Nevertheless, since the Maxwell-Newton approximation has been proven as the first order of a physical metric, the second order approximation of deflection angle can be obtained from measuring the shortest distance from the Sun center. Concurrently, it is shown that the so-called "genuinely measurable quantities," which could be used to make gauge invariant measurements, actually do not exist. As shown in the 1993 press release of the Nobel Committee, many still do not understand Einstein's equivalence principle. Validity of the harmonic metric to the first order and validity of Einstein's equivalence principle can be directly tested by measuring the local light speeds. © 2010 Physics Essays Publication. Source

Lo C.Y.,Pure Research
Physics Essays | Year: 2011

The free falling of a neutral capacitor, though more massive after charged, would be slower. Thus, the claim of Galileo that neutral objects of different masses would fall with the same speed at vacuum is not always true. Nevertheless, the equivalence between gravitational and inertial masses would still be valid. Moreover, Einstein's equivalence principle, which has been misrepresented with distortion to become invalid by the Wheeler School, actually is generally valid, although the charge-mass repulsive force unequivocally shows that acceleration is intrinsically not generally just related to attractive gravity. To verify the equivalence of masses, new experiments should be conducted when the charge-mass interaction is present. To this end, first the experimental confirmation of the details, such as the distance dependence, of such a repulsive force between charge and mass is needed; and this is also a crucial test for general relativity. © 2011 Physics Essays Publication. Source

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