Monday, December 19, 2011


term that is used in microbiology is nanbacteria. Nanobacteria have been claimed in last few years to cause a wide variety of diseases.
Nanobacteria are mineral-forming, sterile-filterable, slow-growing Gram-negative infectious agents [5]. They are detected in bovine/human blood and urine. Nanobacteria-like particles have been detected in synovial fluids of arthritis patients and were shown to gradually increase in number and in size in culture [6].
According to their 16S rDNA structure, nanobacteria belong to the alpha-2 Proteobacteria, subgroup, which includes the Brucella and Bartonella species. Nanobacterium sanguineum (nanobacteria) is the smallest self-replicating organism ever detected—at 50–500 billionths of a meter, 1/1,000th the size of the smallest previously known bacteria [7].
Nanobacteria have been claimed to be associated with a variety of human diseases manifested with pathological calcification. Their most remarkable characteristic is the formation of carbonate apatite crystals of neutral pH and at physiologic phosphate and calcium concentrations. The extracellular mineralization forms a hard protective shelter for these hardy microorganisms and enables them to survive conditions of physical stress that would be lethal to most other bacterial species. Nanobacteria are associated with human kidney stones and psammona bodies in ovarian cancer. Many researchers have thon the potential role these particles may play in the development of urologic pathology, including polycystic kidney disease, renal calculi, and chronic prostatitis. Recent clinical research targeting these agents has proven effective in treating some patients with refractory category III prostatitis [8].
Kidney stones can be debilitating and recur in 50% of patients within 5 years. Kidney stone formation is considered to be a multifactorial disease in which the defense mechanisms and risk factors are imbalanced in favor of stone formation [9].
One theory is that if nanoparticles accumulate in the kidney, they can form the focus of subsequent growth into larger stones over months to years. Other factors, such as physical chemistry and protein inhibitors of crystal growth, also play a role.
Mineral forming nanobacteria are active nidi that attach to, invade, and damage the urinary epithelium of collecting ducts and papilla forming the calcium phosphate center(s) found in most kidney stones. Scientists at NASA have used multiple techniques to determine that nanobacteria infection multiplies faster in space flight simulated conditions than on earth [9].
Nanobacteria are considered to initiate kidney stone formation as they grow faster in a microgravity environment and may explain why astronauts get kidney stones on space missions. This discovery may prove to be critical for future exploratory missions to the moon and Mars. For further proof to this hypothesis, screening of the nanobacterial antigen and antibody level in flight crew before and after flight would be necessary. This concept also opens the door for new diagnostic and therapeutic techniques addressing nanobacterial infection in kidney stones.
Nanoparticles, isolated from renal stones obtained at the time of surgical resection, have been analyzed and propagated in standard cell culture medium [10]. Nanoparticles were isolated from the majority of renal stones. Isolates were sensitive toward selected metabolic inhibitors and antibiotics and contained conserved bacterial proteins and DNA. These findings suggest that renal stone formation is unlikely to be driven solely by physical chemistry; rather, it is critically influenced by specific proteins and cellular responses, and understanding these events will through lights toward new therapeutic targets. Using high-spatial and energy resolution near-edge x-ray absorption fine structure at the 25-nm spatial scale, it is possible to define a biochemical signature for cultured calcified bacteria, including proteins, polysaccharides, nucleic acids, and hydroxyapatite [11].
These preliminary reports suggest that nanoparticles isolated from human samples share spectroscopic characteristics with calcified proteins.
Nanobacteria is claimed to be associated with cardiovascular diserases. Scientists at the Mayo Clinic have examined surgical specimens from patients with cardiovascular pathology to predict the presence of nanobacteria [12]. Analysis of areas with positive immuno staining identified spheres ranging in size from 30 to 100 nm with a spectral pattern of calcium and phosphorus (high-energy dispersive spectroscopy).
Nano-sized particles cultured from calcified but not from non calcified aneurysms were recognized by a DNA-specific dye, incorporated radiolabeled uridine, and after decalcification, appeared via electron microscopy to contain cell walls. Therefore, nanometer-scale particles can be visualized in and cultured from human calcified cardiovascular tissue. In a further study nanoparticles were found near plaque-filled arteries in animal models. The study suggests that nanoparticles potentially represent a previously unrecognized factor in the development of arteriosclerosis and calcific arterial disease [12].

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