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1.
Astrobiology ; 19(9): 1177-1185, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31397580

RESUMO

The Planetary Society's Phobos Living Interplanetary Flight Experiment (Phobos LIFE) flew in the sample return capsule of the Russian Federal Space Agency's Phobos Grunt mission and was to have been a test of one aspect of the hypothesis that life can move between nearby planets within ejected rocks. Although the Phobos Grunt mission failed, we present here the scientific and engineering design and motivation of the Phobos LIFE experiment to assist with the scientific and engineering design of similar future experiments. Phobos LIFE flew selected organisms in a simulated meteoroid. The 34-month voyage would have been the first such test to occur in the high-radiation environment outside the protection of Earth's magnetosphere for more than a few days. The patented Phobos LIFE "biomodule" is an 88 g cylinder consisting of a titanium outer shell, several types of redundant seals, and 31 individual Delrin sample containers. Phobos LIFE contained 10 different organisms, representing all three domains of life, and one soil sample. The organisms are all very well characterized, most with sequenced genomes. Most are extremophiles, and most have flown in low Earth orbit. Upon return from space, the health and characteristics of organisms were to have been compared with controls that remained on Earth and have not yet been opened.


Assuntos
Exobiologia , Meio Ambiente Extraterreno , Planetas , Voo Espacial , Temperatura Alta , Meteoroides , Radiação
2.
Pediatr Res ; 67(5): 490-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20094006

RESUMO

Calcification, a phenomenon often regarded by pathologists little more than evidence of cell death, is becoming recognized to be important in the dynamics of a variety of diseases from which millions of beings suffer in all ages. In calcification, all that is needed for crystal formation to start is nidi (nuclei) and an environment of available dissolved components at or near saturation concentrations, along with the absence of inhibitors for crystal formation. Calcifying nanoparticles (CNP) are the first calcium phosphate mineral containing particles isolated from human blood and were detected in numerous pathologic calcification related diseases. Controversy and critical role of CNP as nidi and triggering factor in human pathologic calcification are discussed.


Assuntos
Calcinose/metabolismo , Fosfatos de Cálcio/metabolismo , Nanomedicina/métodos , Nanopartículas , Nanotecnologia , Animais , Apatitas/metabolismo , Bioensaio , Calcinose/diagnóstico , Calcinose/etiologia , Fosfatos de Cálcio/efeitos adversos , Fosfatos de Cálcio/química , Células Cultivadas , Cristalização , Humanos , Valor Preditivo dos Testes
3.
Urology ; 73(1): 210.e11-3, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18718644

RESUMO

Spaceflight-induced microgravity appears to be a risk factor for the development of urinary calculi, resulting in urolithiasis during and after spaceflight. Calcifying nanoparticles, or nanobacteria, multiply more rapidly in simulated microgravity and create external shells of calcium phosphate. The question arises whether calcifying nanoparticles are nidi for calculi and contribute to the development of clinically significant urolithiasis in those who are predisposed to the development of urinary calculi because of intrinsic or extrinsic factors. This case report describes a calculus recovered after flight from an astronaut that, on morphologic and immunochemical analysis (including specific monoclonal antibody staining), demonstrated characteristics of calcifying nanoparticles.


Assuntos
Calcinose/etiologia , Nanopartículas/efeitos adversos , Voo Espacial , Cálculos Ureterais/etiologia , Bactérias , Humanos , Masculino , Pessoa de Meia-Idade
4.
Int J Nanomedicine ; 3(2): 265-75, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18686786

RESUMO

The nanotechnology industry is currently in the process of producing new nanoparticles. The biological activity of nanoparticles including adverse as well as beneficial effects tends to increase as their size decreases. The smaller the particles are, the greater their bioactivity and toxicity. Thus, one can easily conjecture the impact ofa nanoparticle if it could also self-replicate. This in vitro study reveals the self-propagating ability of unique calcifying nanoparticles (CNP) that can be as small as 50 nm in size and found in blood, blood products, and calcified soft tissues. Although specific detection techniques, morphological characteristics and biomineralizing properties of CNP are well established, their genomic information and self-propagating capability have always been challenged. The objective of this study is to document the propagation of CNP under physiological conditions, using inverted light microscopy (LM) and the Biostation IM time-lapse imaging system. Their detailed morphological structure was examined using scanning (SEM) and transmission (TEM) electron microscopy. This present study, in conjunction with previous findings of metabolic activity, antibiotic sensitivity, antibody specificity, morphological aspects and infectivity, validates CNP as self-replicators. Therefore these sterile-filterable, blood-borne nanoparticles should be of concern to the nanomedicine industry.


Assuntos
Análise Química do Sangue/métodos , Compostos de Cálcio/química , Cristalização/métodos , Nanopartículas/química , Nanopartículas/ultraestrutura , Dimerização , Humanos , Tamanho da Partícula
5.
Int J Nanomedicine ; 3(1): 105-15, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18488421

RESUMO

OBJECTIVES: Randall initially described calcified subepithelial papillary plaques, which he hypothesized as nidi for urinary calculi. The discovery of calcifying nanoparticles (CNP), also referred to as nanobacteria, in calcified soft tissues has raised another hypothesis about their possible involvement in urinary stone formation. This research is the first attempt to investigate the potential association of these two hypotheses. METHODS: We collected renal papilla and blood samples from 17 human patients who had undergone laparoscopic nephrectomy. Immunohistochemical staining (IHS) was applied using monoclonal antibody (mAb) against CNP. Homogenized papillary tissues and serum samples were cultured for CNP. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were performed on papillary samples. Serum samples were tested for CNP antigen and antibody with enzyme-linked immunosorbent assay (ELISA). RESULTS: Randall's plaques (RP) were visible on gross inspection in 11 out of 17 samples. IHS was positive for CNP antigen in 8 of the visually positive samples, but in only 1 of the remaining samples. SEM revealed spherical apatite-formations in 14 samples confirmed by EDS analysis. In cultures, all serum samples and 13 tissue homogenates grew CNP. In ELISA, 14 samples were positive for CNP-antigen and 11 samples were positive for CNP-antibody. CONCLUSION: There was evidence of a link between detection of CNP and presence of RP. Although causality was not demonstrated, these results suggest that further studies with negative control samples should be made to explore the etiology of RP formation, thus leading to a better understanding of the pathogenesis of stone formation.


Assuntos
Calcinose/metabolismo , Calcinose/patologia , Cálculos Renais/metabolismo , Cálculos Renais/ultraestrutura , Medula Renal/metabolismo , Medula Renal/ultraestrutura , Nanopartículas/ultraestrutura , Humanos
9.
Kidney Int ; 67(2): 483-91, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15673296

RESUMO

BACKGROUND: Although some information is available regarding the cellular/molecular changes in immune system exposed to microgravity, little is known about the reasons of the increase in the kidney stone formation in astronauts during and/or after long duration missions at zero gravity (0 g). In our earlier studies, we have assessed a unique agent, nanobacteria (NB), in kidney stones and hypothesized that NB have an active role in calcium phosphate-carbonate deposition in kidney. In this research we studied effect of microgravity on multiplication and calcification of NB in vitro. METHODS: We examined NB cultures in High Aspect Rotating Vessels (HARVs) designed at the NASA's Johnson Space Center, which are designed to stimulate some aspects of microgravity. Multiplication rate and calcium phosphate composition of those NB were compared with NB cultured on stationary and shaker flasks. Collected aliquots of the cultures from different incubation periods were analyzed using spectrophotometer, SEM, TEM, EDX, and x-ray diffraction techniques. RESULTS: The results showed that NB multiplied 4.6x faster in HARVs compared to stationary cultures, and 3.2x faster than shaker flask conditions. X-ray diffraction and EDX analysis showed that the degree of apatite crystal formation and the properties of the apatite depend on the specific culture conditions used. CONCLUSION: We now report an increased multiplication rate of NB in microgravity-simulated conditions. Thus, NB infection may have a potential role in kidney stone formation in crew members during space flights. For further proof to this hypothesis, screening of the NB antigen and antibody level in flight crew before and after flight would be necessary.


Assuntos
Bactérias/crescimento & desenvolvimento , Cálculos Renais/etiologia , Voo Espacial , Ausência de Peso , Bactérias/ultraestrutura , Humanos , Cálculos Renais/microbiologia , Microscopia Eletrônica de Transmissão
10.
J Clin Laser Med Surg ; 21(4): 231-5, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-13678461

RESUMO

OBJECTIVE: The purpose of this preliminary study is to evaluate the effect of various wavelengths of light on nanobacteria (NB). BACKGROUND DATA: NB and mitochondria use light for biological processes. NB have been described as multifunctional primordial nanovesicles with the potential to utilize solar energy for replication. NB produce slime, a process common to living bacteria. Slime release is an evolutionary important stress-dependent phenomenon increasing the survival chance of individual bacteria in a colony. In the cardiovascular system, stress-induced bacterial colony formation may lead to a deposition of plaque. METHODS: Cultured NB were irradiated with NASA-LEDs at different wavelengths of light: 670, 728 and 880 nm. Light intensities were about 500k Wm(-2), and energy density was 1 x 10(4) J m(-2). RESULTS: Monochromatic light clearly affected replication of NB. Maximum replication was achieved at 670 nm. CONCLUSIONS: The results indicate that suitable wavelengths of light could be instrumental in elevating the vitality level of NB, preventing the production of NB-mediated slime, and simultaneously increasing the vitality level of mitochondria. The finding could stimulate the design of cooperative therapy concepts that could reduce death caused by myocardial infarcts.


Assuntos
Bactérias/crescimento & desenvolvimento , Bactérias/ultraestrutura , Luz , Mitocôndrias Cardíacas/efeitos da radiação , Infarto do Miocárdio/prevenção & controle
12.
J Proteome Res ; 2(4): 441-3, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12938934

RESUMO

Life on Earth and Mars could have started with self-assembled nanovesicles similar to the present nanobacteria (NB). To resist extreme environmental stress situations and periods of nutritional deprivation, nanovesicles would have had a chemical composition protected by a closed mineralized compartment, facilitating their development in a primordial soup, or other early wet environment. Their survivability would have been enhanced if they had mechanisms for metabolic communication, and an ability to collect primordially available energy forms. Here, we establish an irreducible model system for life formation starting with NB.


Assuntos
Evolução Química , Exobiologia , Origem da Vida , Apatitas , Bactérias/crescimento & desenvolvimento , Bactérias/ultraestrutura , Divisão Celular/efeitos dos fármacos , Divisão Celular/efeitos da radiação , Meios de Cultura Livres de Soro/farmacologia , Planeta Terra , Meio Ambiente , Marte , Microscopia Eletrônica , Modelos Biológicos
13.
Zhonghua Wai Ke Za Zhi ; 41(4): 267-70, 2003 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12882669

RESUMO

OBJECTIVE: To find the distribution of nanobacteria in the serum, bile and gallbladder mucosa of cholecystolithiasis patients. METHODS: The infection rate of nanobacteria was identified by ELISA in the serum samples from 338 healthy people and 76 patients with cholecystolithiasis (chi(2) = 0.89, P > 0.05). Nanobacteria were cultured from the bile samples in 57 patients with cholecystolithiasis and 18 non-cholelithiasis patients and identified by immunohistochemical staining and TEM (chi(2) = 29.80, P < 0.05). Forty samples of gallbladder mucosa randomly selected from the 57 cholecystolithiasis patients were identified by immunohistochemical staining and compared with the corresponding bile samples. RESULTS: The infection rate of nanobacteria was 8.0% and 31.6% for the serum samples of the healthy people and cholecystolithiasis patients, respectively. The positive rate of nanobacteria in the bile samples was 61.3% and there was no significant difference in the bile of the cholecystolithiasis patients and the control group (61.4% vs. 61.1%). Fourteen positive patients had infection of nanobacteria in the gallbladder mucosa, submucosa, and calcific field. CONCLUSIONS: The infection rate of nanobacteria was 8% in the serum samples from the healthy people. There are nanobacteria in the serum, bile, and gallbladder mucosa. The infection of the nanobacteria may result in calcification and fibrosis of the gallbladder.


Assuntos
Bactérias/isolamento & purificação , Bile/microbiologia , Colecistolitíase/sangue , Colecistolitíase/microbiologia , Vesícula Biliar/microbiologia , Adulto , Bactérias/ultraestrutura , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Mucosa/microbiologia , Adulto Jovem
14.
Urol Res ; 31(2): 47-54, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12669155

RESUMO

Kidney stone formation is a multifactorial disease in which the defence mechanisms and risk factors are imbalanced in favour of stone formation. We have proposed a novel infectious agent, mineral forming nanobacteria (NB), to be 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. Stone formation may proceed in urine supersaturated with calcium phosphate, calcium oxalate and uric acid/urate under the influence of crystallization promoters and inhibitors. Our hypothesis underlines the role of active nidi: even supersaturated urine requires nidi for crystallization to appear.


Assuntos
Bactérias/isolamento & purificação , Cálculos Renais/microbiologia , Bactérias/ultraestrutura , Cristalização , Humanos , Cálculos Renais/química , Cálculos Renais/ultraestrutura , Microscopia Eletrônica de Varredura
15.
Arch. esp. urol. (Ed. impr.) ; 53(4): 291-303, mayo 2000.
Artigo em Es | IBECS | ID: ibc-1301

RESUMO

OBJETIVO: Estudiar el fenómeno de biomineralización aplicado a la litogénesis experimental mediante punción renal percutánea (PRP) sin laparotomía y sin antibióticos de cobertura. MÉTODO/RESULTADOS: Se seleccionaron 4 ratas Brown-Norway para inocular cultivo con cargas bacterianas, X, 2X y 4X de nanobacteria. Una rata actuó de control sin bacterias. Se reseña la evolución clínica analítica y radiológica que conduce a la formación en el riñón inoculado en las ratas nº 2 y 3 de una litiasis pielocalicial obstructiva. CONCLUSIONES: Mediante la punción renal percutánea translumbar (PRP) ha sido posible solventar la dificultad de una laparotomía sin apoyo antibiótico, que era el principal escollo en el modelo de litogénesis experimental. Por otro lado la dificultad para cultivar Nanobacterias ha constituido un reto al proyecto. El haber conseguido la formación de cálculos en el sistema pielocalicial de la rata parece abrir un nuevo horizonte para el conocimiento de esta enfermedad. A la luz de estos avances la interpretación de los resultados que se obtengan parece que sólo ha comenzado, pues son muchos los interrogantes que esconde esta patología (AU)


Assuntos
Ratos , Animais , Ratos Endogâmicos BN , Bactérias , Cristalização , Modelos Animais de Doenças , Cálculos Renais
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