Helicobacter pylori is a human-pathogenic bacterial species that is subdivided geographically, with different genotypes predominating in different parts of the world. Here we test and extend an earlier conclusion that metronidazole (Mtz) resistance is due to mutation in rdxA (HP0954), which encodes a nitroreductase that converts Mtz from prodrug to bactericidal agent. We found that (i) rdxA genes PCR amplified from 50 representative Mtz r strains from previously unstudied populations in Asia, South Africa, Europe, and the Americas could, in each case, transform Mtz s H. pylori to Mtz r ; (ii) Mtz r mutant derivatives of a cultured Mtz s strain resulted from mutation in rdxA; and (iii) transformation of Mtz s strains with rdxA-null alleles usually resulted in moderate level Mtz resistance (16 g/ml). However, resistance to higher Mtz levels was common among clinical isolates, a result that implicates at least one additional gene. Expression in Escherichia coli of frxA (HP0642; flavin oxidoreductase), an rdxA paralog, made this normally resistant species Mtz s , and frxA inactivation enhanced Mtz resistance in rdxA-deficient cells but had little effect on the Mtz susceptibility of rdxA ؉ cells. Strains carrying frxA-null and rdxA-null alleles could mutate to even higher resistance, a result implicating one or more additional genes in residual Mtz susceptibility and hyperresistance. We conclude that most Mtz resistance in H. pylori depends on rdxA inactivation, that mutations in frxA can enhance resistance, and that genes that confer Mtz resistance without rdxA inactivation are rare or nonexistent in H. pylori populations.Helicobacter pylori is a gram-negative microaerophilic bacterium that chronically infects human gastric epithelial cell surfaces and the overlying gastric mucin, a niche that few if any other microbes can occupy. It is carried by more than half of all people worldwide and is an important human pathogen: a major cause of peptic ulcer disease, and a contributor to other illnesses, ranging from childhood malnutrition to gastric cancer, and to increased susceptibility to other food-and waterborne pathogens (7,8,32,38,47). There is great intrinsic and public health interest in fully elucidating H. pylori's metabolic pathways and how H. pylori maintains its redox balance during microaerobic growth. Such knowledge should help us to understand the extraordinary chronicity of H. pylori infection and factors that determine whether a given infection will be benign or virulent, elucidate mechanisms of drug susceptibility and resistance, and identify potential targets for new effective antimicrobial agents.Here we focus on mechanisms of susceptibility and resistance of H. pylori to metronidazole (Mtz), a synthetic nitroimidazole that is a key component of popular and affordable anti-H. pylori therapies worldwide and that is also widely used against various anaerobic and parasitic infections (13,36,45). Resistance to Mtz is common among H. pylori strains, with frequencies among clinical isolates ranging from 10 ...

The ability of actinic light to modify the proportion of fast and slow forms of the M intermediate (i.e., Mf and M(s)) in the bacteriorhodopsin (BR) photocycle is lost by exposure of the purple membrane (PM) to 0.05% Triton for 1-2 min. The decay path of Mf through the O intermediate is also lost, and new, much slower kinetic forms of M appear. In this brief exposure, the trimer structure for BR, as measured by circular dichroism (CD) exciton coupling and sedimentability, is unaffected. The optical properties of the treated PM are affected within seconds of exposure to the detergent as indicated by an increase in transmittance and a blue shift in the wavelength of maximum absorbance for the ground state. Different concentrations of Triton cause reproducibly different changes in the kinetics of the system. These observations support the view that the BR trimer-membrane interaction is important in controlling the BR photocycle.

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Acne, also known as acne vulgaris (AV), is a long-term skin disease that occurs when hair follicles are clogged with dead skin cells and oil from the skin. It is characterized by blackheads or whiteheads, pimples, oily skin, and possible scarring. An intact stratum corneum and barrier, normal natural moisturizing factor and hyaluronic acid levels, normal Aquaporin-3 (AQP3) expression (localized at the basal lateral membranes of collecting duct cells in the kidney), and balanced sebum secretion are qualities of the skin that fall in the middle of the oily–dry spectrum. Patients rarely, if ever, complain about reduced sebum production, but elevated sebum production, yielding oily skin that can be a precursor to acne, is a common complaint. Several factors are known to influence sebum production. AV is mostly triggered by Propionibacterium acnes in adolescence, under the influence of normal circulating dehydroepiandrosterone (DHEA). It is a very common skin disorder which can present with inflammatory and noninflammatory lesions chiefly on the face but can also occur on the upper arms, trunk, and back. Age, in particular, has a significant and well-known impact, as sebum levels are usually low in childhood, rise in the middle-to-late teen years, and remain stable into the seventh and eighth decades until endogenous androgen synthesis dwindles. Sebum, the oily secretion of the sebaceous glands containing wax esters, sterol esters, cholesterol, di- and triglycerides, and squalene, imparts an oily quality to the skin and is well known to play an important role in acne development. Acne can’t be prevented or cured, but it can be treated effectively. The pimples and bumps heal slowly, and when one begins to go away, others seem to crop up. Depending on its severity, acne can cause emotional distress and scar the skin. Acne may cause scarring of the skin, but generally causes no long-term health problems. In self-body image, some parts of the body including face play an important role. Existence of even a minor lesion in this part may be unpleasant for the patient and seems large. This image can cause mental disorders including depression and anxiety, low self-esteem, and decrease in social relationships. However, high levels of anxiety and depression in patients with facial acne are not related to oxidative stress, according to a study published online in the Journal of Cosmetic Dermatology

Objectives: This study aims to evaluate the psychiatric symptoms, quality of sleep, quality of life and the predictive factors affecting quality of sleep in patients diagnosed with nasal septal deviation (NSD). Patients and Methods:Forty male patients (mean age 22.3±1.4 years; range 21 to 26 years) who admitted to the otorhinolaryngology (ORL) clinic of the Ağrı Military Hospital and diagnosed with NSD as a result of a through ORL examination between February 2009 and April 2009 and 36 healthy volunteer (mean age 21.7±1.0 years; range 21 to 25 years) controls, were included in this study. Preand postoperative evaluations were performed using the Quality of Life Scale (Short Form-36/SF-36), the Pittsburgh Sleep Quality Index (PSQI) and the Symptom Check List Revised (SCL-90-R).Results: All patients and controls completed pre-and postoperative evaluations. No complications occurred. There was a statistically significant difference between the groups in the quality of sleep measures, in the SCL-90-R subscales of somatization, obsession, interpersonal sensitivity, depression, anxiety, phobic anxiety, hostility, paranoid thought, and psychoticism, additional scales and in physical health dimension of SF-36 Quality of Life Scale. Conclusion:Psychiatric symptoms are more common in patients with nasal septal deviation when compared to healthy controls. The impairments in nasal breathing in patients with NSD may cause a decline in the physical dimension of quality of life and a marked impairment in sleep quality.Key Words: Nasal septal deviation; psychiatric symptoms; quality of life; quality of sleep. Sonuç: Sağlıklı kontrollerle karşılaştırıldığında, psikiyatrik semptomlar nazal septal deviyasyonlu hastalarda daha fazladır. Nazal septal deviyasyonlu hastalarda nasal solunumla ilgili bozukluklar, yaşam kalitesinin fiziksel boyutunda azalmaya ve uyku kalitesinde belirgin kötüleşmeye neden olabilmektedir.Anahtar Sözcükler: Nazal septal deviyasyon; psikiyatrik semptomlar; yaşam kalitesi; uyku kalitesi.