Wednesday, February 22, 2012

This is not surprising: the latest bibliographic ...

In our systematic review and meta-analysis, we found a high degree of heterogeneity between trials on the effectiveness nekon'yuhirovannoho >> << pneumococcal polysaccharide vaccine in prevention of a number of clinical cases. Much of this heterogeneity can be explained by


differences in methodological quality of trials. We found little evidence of protection of the elderly >> << or adults with chronic respiratory diseases for which pneumococcal vaccine is recommended in many industrialized countries. Tests of higher quality (ie, double-blind design and adequate concealment of allocation) generally show


little evidence that the strattera cost protective effect of vaccine, regardless of the study population and setting. The first meta-analysis of studies of pneumococcal polysaccharide vaccine, published in 1994, reported a protective effect on the final


predictable and pneumococcal pneumonia. Since then, numerous meta-analyzes were published, some of which are aimed at specific groups or the results of (a >> << meta-analysis is given in Annex 3, at


). Several meta-analyzes reported protective effect of vaccines on all causes of pneumonia in subgroups such as low-risk


groups or people with low incomes. ,,


Some of the earlier meta-analyzes agreed with our finding no conclusive evidence for vaccine associated with a reduced risk >> << of all-cause pneumonia, especially in elderly or chronically ill people. ,,,,


Conclusions for other decisions, often contradictory, especially for invasive pneumococcal infections. ,,,,


Last Cochrane review found evidence supporting the effectiveness of vaccines against invasive pneumococcal infection, reporting a combined ratio of treatment


0. 26 (95% CI 0. 15BЂ "0. 46). This finding contrasts with our result (combined RR 0. 90, 95% CI 0. 46BЂ. "1 77) and significantly


due to the inclusion in Cochrane reviews, in 1977, research involving Papua New Guinea Highlanders


in 1947, research involving older people in New York. We excluded the Papua New Guinea study, so that the material considered for the diagnosis of invasive pulmonary diseases included aspiration and that access to medical and diagnostic


procedures were limited. We excluded New York


research from our analysis of invasive pneumococcal infections, since a large number of participants volunteered to be vaccinated


were not randomly distributed in the vaccine group. Of the 17 meta-analyzes of pneumococcal polysaccharide vaccine, which we identified, 13 assessed quality of trials (usually


composite score) and 10 studies used for quality assessment and sensitivity analysis excluded studies with the lowest quality ratings >> << . However, no previous meta-analysis is formally study the quality of their analysis as a means of >> << explore the causes of heterogeneity of results, as we did. This is not surprising: the latest bibliographic research 272 meta-analysis of clinical trials



found that 140 (52%) rated the quality of components research, but only 66 (24%) stratified analysis for quality testing . You can expect that the observation study, due to their nature, would be more likely than randomized controlled trial


show the protective effect of vaccine. The situation observed in the literature on influenza vaccination, where


3 beneficial effects of bacteria

cohort study showed a significant reduction in mortality from all causes, in contrast to the results of randomized controlled trials. These conflicting results may be explained by selection bias, if vaccinated individuals were at lower risk results >> << than unvaccinated people. Studies in the U.S. recorded substantial racial and ethnic differences in the absorption of vaccination and


revealed that some positions and preferences are important factors for absorption prevention


in general. ,


These relationships are also important predictors of outcome: participants of clinical trials that adhere to prescribed drugs


Does active treatment or placebo, found that mortality compared with those who do not follow


prescribed medications. ,


On the other hand, people with a skeptical attitude to health increased mortality, possibly due to a higher level


unhealthy lifestyle. Most observational studies of pneumococcal polysaccharide vaccine reported large protective effect. For example, recently caseBЂ "control analysis of long-care setting in Austria have found strong evidence (p


0. 0001) to reduce the risk of pneumonia (odds ratio 0. 28) and death (odds ratio 0. 27). Even within the oversight of research, some of them showed little effect. A large cohort study in the U.S. showed little evidence


protective effect of vaccine against pneumonia in the elderly, but it shows a protective effect against >> << pneumococcal bacteremia. Conflicting results between observational studies and clinical trials of lower and higher methodological quality artwork


difficulties in interpreting results of studies on the risk of errors. Empirical evidence and theoretical considerations support the view that the test above methodological quality will provide results


closer to the truth, the lower the quality of research. ,,


Meta-analysis can not prove that it is necessary in this case, since other factors associated with both quality testing


and the results could confuse the analysis. For example, the immunogenicity of different antigens of pneumococcus vaccine


. changes and differences in the distribution of serotypes of different studies can be expected to introduce some heterogeneity


Notably, when we restricted the analysis to studies of higher quality, we found that between investigators heterogeneity was reduced,


which opposes the presence of important mixed. Interestingly, the blinding was more important than allocation concealment >>. << No, no dazzling allocation concealment is important for mortality from all causes. This is in accordance with


recent study that examined 146 meta-analysis of clinical trials with different results. During the trials with subjective results, the effect estimates exaggerated when there was no blinding or concealment >> << distribution was not enough, however, there was no sign of a shift in research to results, including mortality from all reasons. Fedson,


in 2003, argued that clinical trials of pneumococcal polysaccharide vaccine were BЂњdestined initially be inconclusiveBЂ "


because they suffered from methodological problems and were too small to reliably show the effect of pneumonia on all causes. We included


several studies published since then and found that, when we restricted our analysis of studies of higher quality, essential >> << beneficial effect on all causes of pneumonia were excluded with certainty. This does not apply to some other results


particular invasive pneumococcal disease, as analyzes were based on multiple trials and multiple events. Mangtani and colleagues


argued that the pneumococcal polysaccharide vaccine can prevent pneumococcal bacteremia but not pneumonia because of poor


, Manufacturing opsonizing antibodies. Our results are not inconsistent with this opportunity, but also provide little evidence for this. Concern that our meta-analysis of high-quality research does not rule out harmful effects of pneumococcal polysaccharide vaccine >> << to prospective pneumonia or pneumonia from all causes. A large cohort study from the U.S. also showed increased risk >> << among the elderly. Our results for all causes of pneumonia were strongly influenced by a double-blind study in HIV-infected adults in Uganda


, which showed a significant, harmful effects of vaccines. The authors proposed a mechanism associated with HIV infection, which may explain the harmful effects. However, they also suggested


which may be more common, yet unknown, explain. . << >>

Compared with other bacterial abscesses ...

In this case, select a specific aspect of Klebsiella pneumonia liver abscess occurring disease in the United States and Western countries. We announce two cases of Asian patients with Klebsiella liver abscesses associated estimated in our institute for one year. Both >> << are non-specific symptoms at presentation, a kind of ultrasonic appearance >> << and successful treatment of early percutaneous drainage. Klebsiella related liver abscess occurring disease with particular clinical characteristics. As


compared to other bacterial liver abscesses, Klebsiella pneumonia


Related festering abscesses of liver has different risk factors unique ultrasound


and computed tomography features and different prognoses. Abscess liver abscess (PLA) is a potentially life-threatening disease that can be caused by >> << bacterial or fungal organisms. The most common bacteria isolated from liver abscess patients


Gram-negative bacillus. By the end of last century,


E. coli was recognized as the main cause of bacterial abscesses liver [], but recently >> << Klebsiella pneumonia was the leading agent in Asian and Western countries [


]. Here we describe two cases of Klebsiella associated PLA have been investigated and successfully treated in our department. 29-year old Indian man reported the 4-day history of fever, chills and fatigue. He


previously been in good health. He emigrated to Italy nine years ago. He denied


latest trip abroad. On general examination the temperature is 40 `C, lung, heart and abdominal examinations


found no abnormalities. Laboratory tests differed leukocytosis (14 040


3 different types of bacteria

cells / mm


), total bilirubin 1. 6 mg / dL, alanine transferase 100 U / L, aspartate transferase-69


U / L. Chest X-ray showed increased right right or left dome of diaphragm. The patient was empirically


received intravenous levofloxacin and ceftriaxone, but the peaks of fever persists. Three days after admission the patient developed right upper quadrant abdominal pain >>. << Abdominal ultrasound (U.S.) showed a diameter of 10 cm lesion in right lobe


liver. Computed tomography (CT) showed a 10 cm hypodense lesion with


internal partitions (Fig.


). US-guided percutaneous drainage was placed 150 ml of purulent brings fluid


but no pathogen was isolated from the culture atmosphere manure. Entamoeba histolytica serology was negative. Two of three blood cultures grew Klebsiella pneumonia


resistant to levofloxacin. Thus, the patient intravenous gentamicin strattera price and metronidazole


. This therapy led to clinical improvement and percutaneous drainage has been deleted. Abdominal U.S. to extract showed a significant reduction in size of the abscess. The patient was discharged


antibiotics were switched to oral ciprofloxacin and metronidazole


6-week course. Further U.S. after antibiotic therapy showed resolution


abscess. The patient turned to his normal health. 76 year old Chinese presented a 5-day history of fever spikes and chills. Previously, he was in good health, history found >> << cholecystectomy for cholelithiasis ten years ago. Overview showed significant hypotension (85/50 mmHg) and temperature >> << 41 `C, while others consider it was nothing remarkable. Laboratory tests showed elevated


C-reactive protein (31 mg / dl, normal value1), violation of serum creatinine


(1. 8 mg / dL), aspartate-transferase (139 U / L), alanine transferase (110 U / L), alkaline phosphatase


(823 U / L) and total bilirubin (2. 12 mg / dl). The patient was treated with


fluid and empirical antibiotic therapy with piperacillin-tazobaktam started. Abdominal U.S. showed 3 cm in diameter lesion in the right lobe of liver. Abdominal


CT confirmed the presence of 3 cm hypodense lesion with irregular fields strongly


suspicious metastatic tumor liver. Percutaneous catheter drainage was made. Diagnostic aspiration lesions given 50 ml of purulent material grew Klebsiella pneumonia


. Three blood cultures grew Klebsiella pneumonia


sensitive to all antibiotics. Entamoeba histolytica serology was negative. Clinical conditions of patients improved, abdominal U.S. to discharge showed complete resolution of liver abscess


. The patient was discharged and treatment on an outpatient basis with


levofloxacin and metronidazole for 4 weeks. First reported from Taiwan as a single organism in PLA [], recent research


Klebsiella pneumonia was recognized as the leading agent of PLA in Asia and Western countries [


]. In addition, it was found that due to the Asian ethnicity, diabetes


and liver abscesses kryptohennyy


[,,


]. On the other hand, the presence of cholelithiasis and malignant coexisting been recognized as an intellectual



parameter E. coli PLA []. Patients often complain of indefinite constitutional symptoms such as fever and fatigue,


still only half the battle represented a specific clinical clues right upper quadrant


pain, jaundice and hepatomegaly


[


]. Only non-specific symptoms were found in our case, even in the first >> << patient who was so large PLA (10 cm). For this reason, the absence of the upper right abdominal quadrant


results do not rule out liver abscess. In addition to NOAK


always be considered in the differential diagnosis of fever of unknown origin. Distinctive features of U.S. and CT have been reported in Klebsiella pneumonia PLA [


]. Mostly solid U.S. appearance of lesions with irregular margins observed in



Klebsiella related liver abscesses, probably because of their refusal liquefaction


[]. Compared with other bacterial abscesses, fewer pus obtained at initial aspiration


reported in the


Klebsiella PLA [], which may be related to their preferred dense consistency of aggregation


in a few cells that do not communicate. These features are observed in our patients,


especially in the second, where the liver, the tumor was considered in the diagnosis >> << differ. Some studies have shown a better prognosis for patients with Klebsiella associated PLA than for other bacterial abscesses liver [


]. However, a higher frequency of metastases to other sites of infection has been shown in patients with



Klebsiella associated PLA []. The most common manifestation of metastatic infection endoftalmitu, meningitis and



brain abscess []. The main factors of virulence of Klebsiella pneumonia


been shown to be associated with metastatic disease. K1 capsule serotype is


important factor for virulence of septic eyes and central nervous system complications



PLA []. In addition a number of clinical studies indicate a connection between >> << hypermucoviscosity phenotype


Klebsiella pneumonia and the presence of invasive disease has spread to infection []. Klebsiella pneumonia strains have hypermucosviscosity phenotype if they are capable of producing


mucoviscous web ekzopolisaharydu. In the microbiological laboratory, these strains


grow in colonies on the sticky cups with agar and identified a line test. Although


diabetes was considered a major risk factor for


Klebsiella associated PLA, data conflict as to whether this is related to invasive and metastatic



infection []. None of our patients with diabetes, none of them felt the eye or neurological complications.


The significant reduction in mortality occurred in all the festering abscesses of liver


since 1950, possibly due to the advent of percutaneous drainage and wide spectrum antibiotics


[]. Unlike amebic abscess, drainage of purulent abscesses should in most cases


This issue highlights Cheng et al. (2003)



[], who noted that early drainage can significantly improve the prognosis. Percutaneous drainage


. is a relatively low risk and effective method. It gradually replaced


surgical procedures, as has been shown to reduce the cost and length of stay in hospital


[]. Surgical drainage should be considered in patients with multiple and large liver abscesses


and if no response to percutaneous drainage


[]. In addition to drainage, treatment


Klebsiella liver abscess requiring parenteral antibiotics. With outpatient


Klebsiella strains resistant to first generation cephalosporins and ampicillin, but rarely


produce extended spectrum beta-lactamase (ESBL), a combination of extended spectrum


beta-lactam and aminoglycosides is the best treatment. Although aminoglycosides


penetrate the abscess cavity is bad, it can quickly eradicate organisms in >> << bloodstream and reduces the risk of metastatic disease. CT: computed tomography; ESBL: extended spectrum beta-lactamases, PLA: Purulent liver abscess


, U.S.: ultrasound. Written informed consent was obtained from patients for publication of these thematic


reports and accompanying images. A copy of the written consent is available for viewing


chief editor of the magazine. The authors declare that they have no competing interests. FC was a major contributor in writing the manuscript; LF participated in the diagnosis and management


disease; VR performed abdominal CT scan; GR is a major >> << contribution to writing the manuscript, MD was involved in the diagnosis and management


disease; TM produced by abdominal ultrasound, Russia was a major contributor in writing


manuscripts. .


We also plan to retrospectively identify...

3 bacteria shapes

Background. Necrotizing fastsyyt rapidly progressing, life-threatening infection that primarily involves the soft tissues. Traditionally, group A streptococcus is a major cause of the disease. In recent years, however, an increasing number of reported cases of necrotizing fastsyyt exclusively caused by Klebsiella pneumonia. There are limited data on clinical and microbiological features of K. pneumonia strains causing the disease. The methods. We plan to review medical records necrotic fastsyyt treated during 1996-2009 to the National Taiwan University Hospital, and compare the clinical features of cases caused by pneumonia and K cases caused by streptococcus strattera dosage group A. We also plan to retrospectively identify necrotic fastsyyt related K. pneumonia strains stored at 80 ° C, the National Taiwan University Hospital, and perform virulence phenotyping related hypermucoviscosity, wzy (Mage locus), rmpA genotyping, and 20 kb Kraft / CTV genome. Expected results. This study is expected to provide the following important information: (1) the prevalence of monomicrobial necrotizing pneumonia K. fastsyyt cases among all cases of necrotizing fastsyyt in our clinic during the study period (2) different clinical signs of pneumonia K. necrotizing fastsyyt using the group A streptococcus necrotizing fastsyyt as in the comparison group (3) microbiological characteristics of K. pneumonia strains causing monomicrobial necrotizing fastsyyt, including hypermucoviscosity phenotype, wzy (Mage locus) and rmpA genotype. .

There are many types of antibiotics.

What are antibiotics? Antibiotics are medicines that kill bacteria. Bacteria can cause infections such as


, ,,, and


infections (). There are many types of antibiotics. Each works a little differently >> << and operates on different types of bacteria. Your doctor will decide which antibiotic


will work best for infection. Not all antibiotics cure? Antibiotics are powerful medicines, but they can not cure


everything. Antibiotics do not work against illnesses that are caused. They do not help illnesses such as:


cold. In most cases. Most sore throats not caused by


. Undead. These diseases usually are themselves. Ask your doctor


what you can do to feel better. Why not take antibiotics just in case? If you take antibiotics if you do not need them, they can not


work when you need them. Every time you take antibiotics, you are more likely >> << have some bacteria that the medicine does not kill. Over time, these bacteria


change (mutated) and harder to kill. Antibiotics are used to destroy


them no longer work. These bacteria are called antibiotic-resistant bacteria.


These tough bacteria can lead to longer and more serious infections.


For their treatment may need another, more powerful antibiotics that


expensive. Strong antibiotic may have more side effects than the first medicine >>. << Antibiotic resistant bacteria may also spread to family members, children


, and colleagues. Your community then there is a risk of


infections harder to treat and is more expensive to treat. Some antibiotics >> << that doctors prescribed in the past to treat common infections no longer work. When antibiotics do not need will not help you feel better


cure, or keep others from infection. But taking th


can cause harmful side effects. Common side effects include: .. Pain. Antibiotics can also cause (also called C. difficile colitis


), swelling and irritation. This is because antibiotics kill


normal bacteria in the intestines and allow


C. difficile


bacteria to grow. This problem strattera online can cause diarrhea and cramping abdominal


. In rare cases it can lead to death. Women can get on antibiotics. In rare cases, antibiotics can cause dangerous >> << that requires emergency care. How can I help to make sure that antibiotics are the best treatment for me? Be smart about using antibiotics. Know that antibiotics can help


treat infections caused by bacteria, not viruses. Here are some things >> << you can do to help make sure antibiotics will work when you need them:


Always ask your doctor if antibiotics are better than cure. Explain that you do not want antibiotics, if you want


them. Avoid pressure on the doctor in prescribing antibiotics


, when they help you feel better or cure disease. Ask your doctor what


more you can do to feel better. Do not use antibiotics that have been proposed for


various diseases or for someone else. You may delay correct treatment


and become worse. Protect yourself from disease. Keep


hands clean, wash them with soap and clean running water. Get the


and other vaccines when you need them. .


The symptoms of trichomoniasis include heavy ...

The main types of common vaginal infections mentioned here briefly. For more information about certain types of vaginal infections, see. the link. Almost all women have Candida Albicans increasing damage to the vagina. Changes in the vaginal environment can mean the yeast grows more than normal, resulting in thrush (vaginal candidiasis). Bacterial vaginosis occurs when bacteria that live naturally in the vagina grow larger than normal (eg,


Gardnerella vaginal). It is the most common cause of vaginal discharge in women of childbearing age. Vaginal discharge is strattera 25mg usually thin and gray with fish odor. BV is not a venereal disease, although there may be in communication with a new sexual partner or a large number of life sexual partners. If left untreated, BV can increase the risk:


skin bacteria

Trichomoniasis is caused by a parasite Trichomonas. It is usually transmitted by unprotected sex. The symptoms of trichomoniasis include a heavy, frothy, yellow-green, fishy smelling vaginal discharge. However, half of women with trykhomoniasus not have any symptoms. If left untreated, the infection trichomoniasis can lead to an increased risk:


Chlamydia is the most common STI in the UK. It is caused by a bacterium


chlamydia, which destroys the cells of the mucous membrane of the cervix and other tissues. Many people have chlamydia without knowing it. Seven of 10 women and half of men with chlamydia have no symptoms. In women, chlamydial infection can spread to the uterus (womb), ovaries and fallopian tubes and cause PID. From one to four women in 10 of raw chlamydia get PID. PID can damage the fallopian tubes and may increase the risk:


Gonorrhea is caused by bacterium Neisseria gonorrhea, which is transmitted during unprotected sex. Symptoms of gonorrhea usually appear within two weeks after infection and may include:


However, half of women with gonorrhea do not have any symptoms. Genital herpes infection caused by herpes simplex virus (HSV) that is transmitted during unprotected sex. After HSV infection remains in your body for life. Genital warts are the most common sexually transmitted viral infections in the UK, particularly in men aged 20 years and 16 to 19-year old woman. Acute warts caused by human papilloma virus (HPV), which makes cells grow oddly. You can catch genital warts, having sex and / or skin-to-skin with those who they are. Acute warts appear as small round lumps on or around the vulva, thigh, cervix, vagina or anus. It may take months or even years after infection for warts to show up. However, many people with the virus do not develop warts, and you may not know, you have the infection. .

Bacteria that retain the purple stain ...

"Classified by color grams. This process, which determines many things R resistance to antibiotics, with one hand. It is also one of the first things scientists are doing when trying to identify unknown bacteria. It includes a painting of a group of bacteria with four different liquids. First, crystal violet added. Then itHs painted with iodine, and finally safranina. It then passes through the alcohol wash. Bacteria that retain the purple stain of crystal violet are gram-positive and those who take on the pink spots on safranina are Gram-negative. "


plasmid in bacteria

"This is the outside layer of cells R gram-positive bacteria a thick layer of peptidoglycan, which absorbs grams. Gram-negative bacteria strattera dosing a thick lipid layer on the outside, which is selectively permeable P not everyone can go through it, and one of those things grams. Gram-positive bacteria (as it can go through it easily) is much more sensitive to antibiotics than gram-negative bacteria. "(

There were 2,236 hiv-negative people in the group

Man Who


in relation to HIV-infected woman is three times higher risk of HIV infection >> << if his partner as bacterial vaginosis, said Craig Cohen



(IAS 2011) in Rome today. While it was previously


found that bacterial vaginosis increases the risk of a woman's HIV infection


This is the first time been shown to increase its risk of >> << sexual partners. Bacterial vaginosis


(BV) is a condition that occurs when the normal balance of bacteria in the vagina strattera cost


is broken. This can lead to excessive growth of some bacteria


. (flora), which may be accompanied by symptoms such as discharge, itching and pain


This sometimes can lead to pelvic inflammatory disease


and cause problems with fertility and childbirth. found that, BV is associated - for women -


, with an increased risk of HIV infection. Investigation of risk male HIV


when their sexual partners bac until


line. But


some studies have shown that BV is associated with an increase in HIV viral load >> << in the genital tract. that HIV-infected women


bacterial vaginosis, when they give birth, are at greater risk of HIV transmission


for your child. Craig Cohen


data analysis presented in pairs to work in partners to research


Warning conducted in seven countries of Southern and Eastern Africa. There were 2,236 HIV-negative men in the cohort >> << who was HIV-positive female partner. Both partners were under observation for


two years. Couples were


been together for an average of five years and three quarters were married. Third


reported unprotected sex, although condoms and counseling were provided


researchers. HIV-infected partner had a CD4 cell


Number of above 250 cells / mm


and not on HIV treatment early


research. After more than 10000


tours, which evaluated the vaginal flora, 34. 9% of women had bacterial vaginosis


, 22. 8% had intermediate flora, and 42. 8% had normal flora. In the course


research, 57 of them were HIV-positive when HIV genotyping (ENV



and gag) can confirm that they were like a virus that their partner. In


, In other words, they are probably not infected with HIV beyond initial relationship >>.


Researchers have identified, the measurement of vaginal flora for their partners


which was taken close to the estimated date of seroconversion (up


than three months earlier). This data is not enough for seven women, resulting in


50 pairs in the analysis. Nine HIV  


programs run by women with normal flora, ten of the women with intermediate flora


and 31 women with bacterial vaginosis. After


h polaris bacteria

control a large number of potentially interfering factors


(socio-demographic, behavioral and biological), people whose partners had BV >> << three times higher risk of contracting HIV than other men (risk ratio of 3. << 06 >> 95% confidence interval, 1 35 - 6. 95) .. Women with the same


BV have higher genital viral load (3 23. Magazine, compared with 3. Journal 04 Women


, with normal flora). This was statistically significant, but Cohen suggested


that is probably not clinically significant. He nominated


two other hypotheses that could explain the increased risk for male partners. First, the normal bacteria that may be virucidial against HIV, reducing the share


virus that is contagious. Second, that bacterial vaginosis may


indirectly increases the susceptibility of male partners to HIV. Cohen said that


long-term sexual partners share sexual flora, with men buying bacteria


from their partners. Perhaps, he suggested that bacteria can activate Langerhans cells


and CD4 + T cells, which makes a person more susceptible to HIV infection.


Important task in working on this study is that the current strategy for treatment of bacterial vaginosis is inadequate, with low levels of treatment and the problem is often repeated. . << >>

Greig particles in magnetosome chains are...

Richard B.


Frenkel Department of Physics, Cal Poly State University, San Luis Obispo, California 93407


(rfrankel @ calpoly. Education)


sensitive to the magnetic behavior of bacteria was found more than 30 years ago


microbiologist Richard P. Blackmore. The discovery was based on the fact that certain


moving, water bacteria orient and migrate along magnetic field lines


under the influence of his magnetic field of the order of the geomagnetic field, or


more. In magnetotactic bacteria (MTB) of the Northern Hemisphere collection


sites, the preferred direction of migration in drops of water and sediment on >> << microscope slide parallel to the magnetic field corresponding to the north


migration of the geomagnetic field. Migration speed of individual bacteria


along magnetic field lines depends on the field, but can be 90% or more


forward speed swimming cells (which can be up to 150 microns per second


). If the local magnetic field direction reversed at MTB


are swimming, they perform a U-turn and continue to migrate to >> << same direction relative to the local magnetic field. The vast migration


MTB areas in the magnetic field may be canceled if >> << cells to a strong (up to several hundred gauss) magnetic field pulse oriented opposite


environmental field. Mtb that spontaneously migrate south along the geomagnetic field lines


in-water sediments and waters of the southern hemisphere.


[For a full description


magnetotaxis see Magnetotaxis in bacteria (MTB All



contain mahnetosomy that nanometer-sized magnetic, mineral crystals enclosed in


; membrane. In most cases mahnetosomy located in a circuit or circuit, perhaps



fixed in cells adjacent to the membrane. Many strains of MTB,


magnetosome magnetite crystals Fe, characterized


narrow size distribution and form vydospetsyfichnist


crystal habit. crystal sizes typically range from approx. 40 to 100 nm, which >> << are in constant, single magnetic domain size range for magnetite. In MTB from marine environments, sulfide, magnetosome crystals << iron-sulfide >> mineral Greig, Fe, which is isostructural


magnetite and also ferrimagnetically ordered at room temperature >>. << Greig crystals are also characterized by narrow size


and distribution of certain habits of the crystal. However, while


magnetite crystals in the magnetosome chains are usually oriented so that [111]


crystallographic axis of each particle is in the chain direction


Greig particles in magnetosome chains are usually oriented so that [100]


crystallographic axis of each lobe oriented along the chain direction. Although most strains of MTB or magnetite or Greig mahnetosomy is


body, which has both magnetite and Greig mahnetosomy organized in chains. << For cells with >>


or magnetite or Greig mahnetosomy, chain mahnetosomy


is the magnetic dipole constant fixed in bacteria. >> << magnetic dipole moment is usually quite large, so and


therefore, bacteria, oriented in heomahnytnom field at room temperature


So magnetotaxis is a passive process in which the orientation >> << magnetic dipole in the surrounding magnetic field, as the body floats


makes it migrate along magnetic field lines. killed cells line up along the


. field, rather than migration. Thus motile MTB to be a self-propelled


magnetic compass needle. Mtb are two possible magnetic polarity in Depending on the orientation of the magnetic dipole


inside the cell. polarity can be changed with a magnetic strattera >> << impulse which more than coercivity chain particles


(several hundred gauss) . Bacteria with reverse polarity migrate along magnetic field lines >> << in the opposite direction that the bacteria with the original polarity >>. << In the natural habitat, the prevailing type of polarity in the population> ;> << this type of bacteria is determined by the sign of the slope


geomagnetic field. It was reported that high concentrations occur in MTB


horizontal plates in an oxygen-anoxic transition zone (OATZ) in chemically


stratified marine environment. In these conditions, oxygen down


diffusion of surface diffusion and upward sulfide, resulting in bacterial


sulfatreduktsii in anaerobic sediments, creating a double vertical


chemical concentration gradient system, redox concomitent gradient.


Salt pond, 5 m deep pond in coastal Falmouth, Massachusetts on Cape Cody, stratified >> << summer OATZ about 3 meters. MTB concentrations >> << plates over 10


cells per ml. in at least seven


morphologically different, sensitive to magnetic fields, bacterial type occurring in OATZ, some


contain particles Fe3O4, and some contain Fe3S4 particles [21 ]. >> << magnetite-containing cells tend to be more abundant in the top of the plate in


relatively oxygen-rich part OATZ, and Greig containing cells


definition of aspiration pneumonia

tend to be more abundant in the lower of plates, in relation


sulfide rich part OATZ. Publications magnetotatic bacteria B. Richard Frenkel (


(


Download the latest review of magnetotactic bacteria, (