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Biomedical subjects

Andrei P Sommer

Publications and source records attributed to Andrei P Sommer.

At least 19 recordsLinked to original sources
PubMed2006

Plants grow better if seeds see green.

We report on the response of dry plant seeds to their irradiation with intense green light applied at biostimulatory doses. Red and near-infrared light delivered by lasers or arrays of light emitting diodes applied at such doses have been shown previously by us to have effects on mammalian cells. Effects include cell proliferation and elevation of cell vitality, and have practical applications in various biomedical fields. Growth processes induced by photoreceptor stimulation (phytochromes and cryptochromes) in plant seeds with green light were described so far only for imbibed seeds. In this paper, we show that irradiation of dry cress, radish and carrot seeds with intense green light (laser or arrays of light emitting diodes), applied at biostimulatory doses, resulted in a significant increase in biomass--14, 26, and 71 days after seeding, respectively. In the case of radish and carrot, the irradiation led to important changes in the root-to-foliage surface ratio. Seeds with a potential to grant growth acceleration could be of special interest in agricultural applications, and could even compensate for shorter growth seasons caused by climate change.

Biomass↗
PubMed2006

Nanobacteria, HIV and magic bullets--update of perspectives 2005.

In 1997 a Finnish group speculated on the presence of nanobacteria in vaccines. In 2001, a report on the identification of nanobacteria in a number of vaccines attracted much attention. Experiments indicated that viable nanobacteria are excreted via urine. Their extreme survivability suggests that prior to discussing any possible contamination of vaccines, sources and routes of natural infection need to be examined. In view of 30,000,000 HIV infections in sub-Saharan Africa, the recently reported occurrence of nanobacteria in HIV-infected patients deserves concern. Clearly, it could indicate the origin of a giant reservoir and dissemination cycle. Here we discuss novel therapeutic strategies to prevent or reduce nanobacterial infection. In regard of the rapid progress in this field, we start with a brief introductory summary, and analyze possible implications.

AIDS-Related Opportunistic Infections↗
PubMed2006

Nanobioaerosols--reconsidering agricultural irrigation in a warming world.

Nanobacteria are best described as 60-300 nm nanovesicles. In the body they collect calcium and phosphate to form apatite, adhere to cells, or invade them--processes regulated by a slime based on proteins (primordial proteins). A versatile functionality realized with a minimum of properties equips nanobacteria with a unique survival potential. They were identified in humans, animals, wastewater and the stratosphere. In South Africa they were detected in people infected with HIV. Models indicate that they boost the genetic diversity of the HIV-1 virus. Experiments showed that they are excreted via urine, explaining their presence in the environment. Eradication would be virtually impossible if they had an extraterrestrial origin, implying a permanent bombardment from space. Whereas the biological status of nanobacteria is still not clarified, we postulate here that the native habitat of nanobacteria are mammals, suggesting that at least modern species have their origin on Earth. The thesis results from mapping functions and properties of the slime, and could facilitate the localisation of nanobacterial reservoirs, identification of local distribution routes and tracking of global transport cycles. Agricultural irrigation with water containing excreta from humans infected with nanobacteria could be a central disseminator of the nanobioaerosols.

Aerosols↗
PubMed2006

Proteobionics: biomimetics in proteomics.

Proteomics was established 10 years ago by the analysis of microbial genomes via their protein complement or proteome. Bionics is an ancient art, which converts structures optimized by nature into advanced technical products. Previously, we analyzed survival modalities in nanobacteria and converted the interplay between survival-oriented protein functions and nanoscale mineral shells into models for advanced drug delivery. Exploiting protein functions observed in nature to design biomedical products and therapies could be named proteobionics. Here, we present examples for this new branch of nanoproteomics.

Animals↗
PubMed2005

Towards rational treatment of bacterial infections during extended space travel.

In the next 15-30 years, manned space flight to Mars, our planetary neighbour, will become a reality and astronauts are likely to spend at least 2-3 years away from Earth. Time spent in such extreme environments will result in a diminution of immune status and profound changes in the human bacterial microflora. In microgravity, the efficacy of antibiotics is reduced and microbial mutation rates increase dramatically. These factors will impinge on the capacity to treat effectively the infections that will doubtless arise during such long and stressful endeavour. We highlight new rationales for the treatment of infectious disease that may be applicable to therapy in extreme environments such as deep space.

Anti-Bacterial Agents↗
PubMed2004

Keeping nanobacterial infections at bay during space travel.

In January 2004, President George W. Bush unveiled plans to send astronauts to the Moon in 2015 and shortly thereafter to Mars. With the prospect of manned exploration of the planets drawing ever closer, the new discipline of Space Medicine is destined to come to the fore. Moreover, investigations of how human beings function under space conditions could provide important new insights into fundamental questions of human physiology and disease. We draw attention here to one such instance of a disease process that can be provoked by extended periods of exposure to low gravity.

Aerospace Medicine↗
PubMed2003

A preliminary investigation into light-modulated replication of nanobacteria and heart disease.

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.

Bacteria↗
PubMed2002

Light-induced replication of nanobacteria: a preliminary report.

OBJECTIVE: The purpose of the present study was to investigate the effect of light on nanobacteria. BACKGROUND DATA: Since their first description in literature, it is not clear whether the nanoparticles called "nanobacteria" are alive or not. The 80-1,000-nm-sized spherical particles are protected by a crystalline carbonate apatite shell and are culturable in cell culture media. Present in mammalians, including humans, nanobacteria seem to cause diseases related to biomineralization processes. Mesoscopic structures found on Martian meteorites and terrestrial rocks indicated that nanobacteria-like biological objects forming apatite, a material fairly transparent to visible light, could have been present on the primitive Earth during an era with the sun as the principal terrestrial energy source. MATERIALS AND METHODS: To evaluate possible biomedical effects of therapeutically relevant irradiation sources on nanobacteria, we irradiated nanobacteria cultures with polarized light and laser-light at low, nonthermal energy density levels. RESULTS: Our observations indicated that nanobacteria are alive. Polarized white light was found to clearly accelerate their replication in vitro, resulting in significant dose-dependent increases in the turbidity of the cultures, compared to nonirradiated controls. Laser irradiation did not affect their replication. CONCLUSION: The possibility that primordial and present nanobacteria could have been not only exposed to, but actively harvested, solar irradiation for their own development suggests itself. Considering that there exists no published material on the action of light on nanobacteria, the reported effects are expected to have an impact on modeling biomineralization processes, associated photoreceptor mechanisms, and astrobiological and evolutionary theories-on Earth and in space.

Bacteria↗
PubMedDate not supplied

Near-field optical analysis of living cells in vitro.

Near-field optical analysis (NOA) provides morphological nanoscale mappings of living cells in liquid cell culture media and nondestructive insight into cell functionality. Here we show for the first time the performance of NOA in imaging living cells. Unlabeled human endothelial cells attached to polished titanium disks were analyzed with hydrophobically coated optical biosensors mounted to a near-field scanning optical microscope (NSOM). Biosensors and titanium substrates could be simply implemented in standard NSOM and high-throughput NOA.

Endothelium↗
PubMedDate not supplied

Living nanovesicles--chemical and physical survival strategies of primordial biosystems.

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.

Apatites↗
PubMedDate not supplied

Sealing porous nanovesicles--solutions inspired by primordial biosystems.

Microcapsules designed for slow drug release have preferably some porosity. There are, however, applications in which a hermetical sealing of the microcapsules is desired. Sealing is not a trivial problem and could be necessary to durably encapsulate toxic compounds which cannot be eliminated from the body, or to encapsulate harmful substances stored in the atmosphere. Nature may have one solution: Nanobacteria have developed surprisingly simple mechanisms to access and use primal energies, and to survive arid periods by sealing their surface.

Bacterial Physiological Phenomena↗
PubMedDate not supplied

Peripheral neuropathy and light-preliminary report indicating prevalence of nanobacteria in HIV.

Peripheral neuropathy is a common condition in HIV-positive patients and is often experienced in diabetes mellitus. The primary mechanism of the disease, which can considerably aggravate the patient's state, is unknown. The perineurium of patients with peripheral neuropathy is frequently enveloped by apatite. Nanobacteria (NB) are protectd by a mineral shell consisting of apatite. Light has been shown to elevate the vitality level of cells, and was predicted to inhibit deposition of stressed NB in the cardiovascular system. Results indicate that light can durably restore the condition of patients with severe peripheral neuropathy.

Apatites↗
PubMedDate not supplied

Suffocation of nerve fibers by living nanovesicles: a model simulation.

A model using nanospheres to allow the simulation of the nonspecific interaction of nanobacteria (NB), one with another or with body tissues, is established. Depending primarily on their concentrations and stress levels, these apatite nanovesicles may nucleate thrombogenic conglomerates in blood, or self-assemble to dense nanoclay layers on surfaces in the body. Partial or total encapsulation of nerve fiber bundles by such mineral layers may interrupt the metabolic exchanges between the surrounded tissue and its immediate environment and may restrict signaling processes. The presented model could provide detailed insight into plaque formation triggered by NB, and the parameters encouraging it.

Apatites↗
PubMedDate not supplied

Primordial proteins and HIV.

Primordial proteins regulate the response of nanobacteria to variations in their environment and reinforce existing pathogenic potentials. By analyzing specific response patterns, we predicted the prevalence of nanobacteria in HIV--and in the atmosphere. A current clinical study indicates the identification of a possibly giant nanobacterial reservoir in Africa: a significant fraction of a test group (40 HIV-infected mothers and 13 babies) was infected with nanobacteria. Concurrently, a multitude of 80-300 nm nanovesicles, apparently nanobacteria, were detected in the atmosphere of the Earth. Nanobacterial infections in HIV are possibly comparable to the twin epidemics HIV and tuberculosis. Models inspired by proteomics recommend methods to inactivate nanobacteria (and other slime-producing bacteria) in the body.

Animals↗
PubMedDate not supplied

Functions and possible provenance of primordial proteins--Part II: microorganism aggregation in clouds triggered by climate change.

Current models predict that the elevation of the Earth's surface temperature due to global warming is accompanied by a warming of the troposphere, and a thickening cloud cover associated with longer-lasting clouds, in particular over land. These effects can have an instant impact on the vitality level of microorganisms in clouds and the spreading of airborne diseases. Microorganisms could originate from locations on the Earth, or even arrive from space. Primordial proteins in nanobacteria, only recently identified in the atmosphere, could play a significant role in clouds--accelerating the formation of cloud droplets and interconnecting nanobacteria (and possibly nanobacteria and other microorganisms), thus enhancing their chances to eventually reach the Earth.

Air Microbiology↗
PubMedDate not supplied

Functions and possible provenance of primordial proteins.

Nanobacteria or living nanovesicles are of great interest to the scientific community because of their dual nature: on the one hand, they appear as primal biosystems originating life; on the other hand, they can cause severe diseases. Their survival as well as their pathogenic potential is apparently linked to a self-synthesized protein-based slime, rich in calcium and phosphate (when available). Here, we provide challenging evidence for the occurrence of nanobacteria in the stratosphere, reflecting a possibly primordial provenance of the slime. An analysis of the slime's biological functions may lead to novel strategies suitable to block adhesion modalities in modern bacterial populations.

Apatites↗
PubMedDate not supplied

Suffocation of nerve fibers by living nanovesicles: a model simulation--part II.

Nanobacteria may cause peripheral neuropathy by adhesion to the perineurium. This hypothesis receives support from five independent observations: (1) identification of perineurial apatite in diabetic patients with peripheral neuropathy, (2) massive presence of nanobacteria in a diabetic patient, (3) beneficial effect of lasers on peripheral neuropathy, (4) model simulation indicating that perineurial deposition and attachment of nanobacteria is encouraged by both their size and chemical nature, and (5) transient inhibition of neural function by apatite. Initial deposition of (stressed) nanobacteria is promoted by a slime thought to consist of proteins, calcium, and phosphate, and is most likely followed by an immobilization phase, mediated by a bioadhesive capacity of the apatite. Proteomics may hold the key to control both attachment processes.

Apatites↗