975 resultados para anti-infective agents


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The formation of toxic protein aggregates is a common denominator to many neurodegenerative diseases and aging. Accumulation of toxic, possibly infectious protein aggregates induces a cascade of events, such as excessive inflammation, the production of reactive oxygen species, apoptosis and neuronal loss. A network of highly conserved molecular chaperones and of chaperone-related proteases controls the fold-quality of proteins in the cell. Most molecular chaperones can passively prevent protein aggregation by binding misfolding intermediates. Some molecular chaperones and chaperone-related proteases, such as the proteasome, can also hydrolyse ATP to forcefully convert stable harmful protein aggregates into harmless natively refoldable, or protease-degradable, polypeptides. Molecular chaperones and chaperone-related proteases thus control the delicate balance between natively folded functional proteins and aggregation-prone misfolded proteins, which may form during the lifetime and lead to cell death. Abundant data now point at the molecular chaperones and the proteases as major clearance mechanisms to remove toxic protein aggregates from cells, delaying the onset and the outcome of protein-misfolding diseases. Therapeutic approaches include treatments and drugs that can specifically induce and sustain a strong chaperone and protease activity in cells and tissues prone to toxic protein aggregations.

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OBJECTIVE: To determine the characteristics of asthma (A) and allergic rhinitis (AR) among asthma patients in primary care practice. RESEARCH DESIGN AND METHODS: Primary care physicians, pulmonologists, and allergologists were asked to recruit consecutive asthma patients with or without allergic rhinitis from their daily practice. Cross-sectional data on symptoms, severity, treatment and impact on quality of life of A and AR were recorded and examined using descriptive statistics. Patients with and without AR were then compared. RESULTS: 1244 asthma patients were included by 211 physicians. Asthma was controlled in 19%, partially controlled in 27% and not controlled in 54%. Asthma treatment was generally based on inhaled corticosteroids (ICS) with or without long acting beta 2 agonists (78%). A leukotriene receptor antagonist (LTRA) was used by 46% of the patients. Overall, 950 (76%) asthma patients had AR (A + AR) and 294 (24%) did not (A - AR). Compared to patients with A - AR, A + AR patients were generally younger (mean age +/- standard deviation: 42 +/- 16 vs. 50 +/- 19 years, p < 0.001) and fewer used ICS (75% vs. 88%, p < 0.001). LTRA usage was similar in both groups (46% vs. 48%). Asthma was uncontrolled in 53% of A + AR and 57% of A - AR patients. Allergic rhinitis was treated with a mean of 1.9 specific AR medications: antihistamines (77%), nasal steroids (66%) and/or vasoconstrictors (38%), and/or LTRA (42%). Rhinorrhoea, nasal obstruction, or nasal itching were the most frequently reported AR symptoms and the greatest reported degree of impairment was in daily activities/sports (55%). CONCLUSIONS: Allergic rhinitis was more common among younger asthma patients, increased the burden of symptoms and the need for additional medication but was associated with improved asthma control. However, most asthma patients remained suboptimally controlled regardl-ess of concomitant AR.

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The potential for mitochondrial (mt) DNA mutation accumulation during antiretroviral therapy (ART), and preferential accumulation in patients with lipoatrophy compared with control participants, remains controversial. We sequenced the entire mitochondrial genome, both before ART and after ART exposure, in 29 human immunodeficiency virus (HIV)-infected Swiss HIV Cohort Study participants initiating a first-line thymidine analogue-containing ART regimen. No accumulation of mtDNA mutations or deletions was detected in 13 participants who developed lipoatrophy or in 16 control participants after significant and comparable ART exposure (median duration, 3.3 and 3.7 years, respectively). In HIV-infected persons, the development of lipoatrophy is unlikely to be associated with accumulation of mtDNA mutations detectable in peripheral blood.

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We review some of the most influential papers from 2012 in the different aspects of emergency medicine, such as prehospital medicine, resuscitation, early diagnosis and timely ED discharge and treatment. In particular, intramuscular benzodiazepines have been shown to be efficient in prehospital status epilepticus, epinephrines usefulness in cardiopulmonary resuscitation has been challenged, colloids have been shown to be deleterious in the treatment of severe sepsis and septic shock, the time window for thrombolysis in acute stroke will probably be extended, acute pyelonephritis treatment duration can be decreased, new D-dimers thresholds for older patients may prevent further diagnosis tests, and hs-Troponin may allow earlier discharge of low coronary risk patients.

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Antibiotics are widely used in critical care and adequate empirical treatments has a significant impact on the outcome of many patients. Most nosocomial infections may be due to multidrug-resistant pathogens and requires empirical borad spectrum coverage before identification of the etiologic agents. This is associated with overuse of antibiotics which contributes to the further increase in multidrug-resistances. In this context, new strategies targeted at antibiotic control, such as guidelines and de-escalation are needed to control this evolution.

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BACKGROUND: We investigated the incidence and outcome of progressive multifocal leukoencephalopathy (PML) in human immunodeficiency virus (HIV)-infected individuals before and after the introduction of combination antiretroviral therapy (cART) in 1996. METHODS: From 1988 through 2007, 226 cases of PML were reported to the Swiss HIV Cohort Study. By chart review, we confirmed 186 cases and recorded all-cause and PML-attributable mortality. For the survival analysis, 25 patients with postmortem diagnosis and 2 without CD4+ T cell counts were excluded, leaving a total of 159 patients (89 before 1996 and 70 during 1996-2007). RESULTS: The incidence rate of PML decreased from 0.24 cases per 100 patient-years (PY; 95% confidence interval [CI], 0.20-0.29 cases per 100 PY) before 1996 to 0.06 cases per 100 PY (95% CI, 0.04-0.10 cases per 100 PY) from 1996 onward. Patients who received a diagnosis before 1996 had a higher frequency of prior acquired immunodeficiency syndrome-defining conditions (P = .007) but similar CD4+ T cell counts (60 vs. 71 cells/microL; P = .25), compared with patients who received a diagnosis during 1996 or thereafter. The median time to PML-attributable death was 71 days (interquartile range, 44-140 days), compared with 90 days (interquartile range, 54-313 days) for all-cause mortality. The PML-attributable 1-year mortality rate decreased from 82.3 cases per 100 PY (95% CI, 58.8-115.1 cases per 100 PY) during the pre-cART era to 37.6 cases per 100 PY (95% CI, 23.4.-60.5 cases per 100 PY) during the cART era. In multivariate models, cART was the only factor associated with lower PML-attributable mortality (hazard ratio, 0.18; 95% CI, 0.07-0.50; P < .001), whereas all-cause mortality was associated with baseline CD4+ T cell count (hazard ratio per increase of 100 cells/microL, 0.52; 95% CI, 0.32-0.85; P = .010) and cART use (hazard ratio, 0.37; 95% CI, 0.19-0.75; P = .006). CONCLUSIONS: cART reduced the incidence and PML-attributable 1-year mortality, regardless of baseline CD4+ T cell count, whereas overall mortality was dependent on cART use and baseline CD4+ T cell count.

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BACKGROUND: Borrelial infection is characterized by various skin manifestations that are usually classified into three main types: chronic migratory erythema, borrelial lymphocytoma and acrodermatitis chronica atrophicans. We report an unusual case of borrelial cutaneous infection presenting as a mediofacial erythema that cannot be included in any of these three categories. CASE REPORT: A 51-year-old woman presented with infiltrated erythema of the middle of the face extending to the neck and chin. Medical history and physical examination revealed no signs of rosaceae. Infection with Borrelia was suspected on skin biopsy examination, which showed an inflammatory dermal infiltrate containing numerous plasma cells. The diagnosis of B.afzelii infection was confirmed by serology and polymerase chain reaction on the skin biopsy, both of which were positive for B.afzelii. DISCUSSION: Borrelial erythema of the face may represent a special form of cutaneous borrelial infection, which must be considered in the differential diagnosis of facial erythema, especially in areas of endemic borreliosis.

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BACKGROUND: An ADME (absorption, distribution, metabolism and excretion)-pharmacogenetics association study may identify functional variants relevant to the pharmacokinetics of lopinavir co-formulated with ritonavir (LPV/r), a first-line anti-HIV agent. METHODS: An extensive search of literature and web resources helped select ADME genes and single nucleotide polymorphisms (SNPs, functional and HapMap tagging SNPs) with a proven or potentially relevant role in LPV/r pharmacokinetics. The study followed a two-stage design. Stage 1 (discovery) considered a Caucasian population (n=638) receiving LPV/r, where we selected 117 individuals with low LPV clearance (cases) and 90 individuals with high clearance (controls). Genotyping was performed by a 1536-SNP customized GoldenGate Illumina BeadArray. Stage 2 (confirmation) represented a replication study of candidate SNPs from the stage 1 in 148 individuals receiving LPV/r. The analysis led to formal population pharmacokinetic-pharmacogenetic modeling of demographic, environmental and candidate SNP effects. RESULTS: One thousand three hundred and eighty SNPs were successfully genotyped. Nine SNPs prioritized by the stage 1 analysis were brought to replication. Stage 2 confirmed the contribution of two functional SNPs in SLCO1B1, one functional SNP in ABCC2 and a tag SNP of the CYP3A locus in addition to body weight effect and ritonavir coadministration. According to the population pharmacokinetic-pharmacogenetic model, genetic variants explained 5% of LPV variability. Individuals homozygous rs11045819 (SLCO1B1*4) had a clearance of 12.6 l/h, compared with 5.4 l/h in the reference group, and 3.9 l/h in individuals with two or more variant alleles of rs4149056 (SLCO1B1*5), rs717620 (ABCC2) or rs6945984 (CYP3A). A subanalysis confirmed that although a significant part of the variance in LPV clearance was attributed to fluctuation in ritonavir levels, genetic variants had an additional effect on LPV clearance. CONCLUSION: The two-stage strategy successfully identified genetic variants affecting LPV/r pharmacokinetics. Such a general approach of ADME pharmacogenetics should be generalized to other drugs.

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BACKGROUND AND OBJECTIVE: Investigations were performed to establish if repetitive arm cycling training enhances the antispastic effect of intramuscular botulinum toxin (BTX) injections in postischemic spastic hemiparesis. Effects on cerebral activation were evaluated by functional magnetic resonance imaging (fMRI). METHODS: Eight chronic spastic hemisyndrome patients (49 ± 10 years) after middle cerebral artery infarction (5.5 ± 2.7 years) were investigated. BTX was injected into the affected arm twice, 6 months apart. Spasticity was assessed using the Ashworth Scale and range of motion before and 3 months after BTX injections. Images were analyzed using Brain Voyager QX 1.8, and fMRI signal changes were corrected for multiple comparisons. RESULTS: During passive movements of affected and nonaffected hands, fMRI activity was increased bilaterally in the sensorimotor cortex (MISI), secondary somatosensory areas (SII), and supplementary motor area predominantly in the contralesional hemisphere, compared with the rest. Following repetitive arm cycling, fMRI activity increased further in MISI of the lesioned hemisphere and SII of the contralesional hemisphere. For patients with residual motor activity, treatment-related fMRI activity increases were associated with reduced spasticity; in completely plegic patients, there was no fMRI activity change in SII but increased spasticity after training. CONCLUSION: Increased activity in SII of the contralesional hemisphere and in MISI of the lesioned hemisphere reflect a treatment-induced effect in the paretic arm. It is hypothesized that the increased BOLD activity results from increased afferent information related to the antispastic BTX effect reinforced by training.

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PURPOSE OF REVIEW: Clinical trials of CCR5 antagonists attest to their efficacy and tolerance in HIV treatment. However, there has been debate on their long-term safety because of the role of CCR5 in innate immunity. This review highlights gaps in our understanding of epidemiology of infections that are modulated by CCR5, in particular, in HIV-infected individuals. RECENT FINDINGS: In the mouse model, CCR5 has a role in the response against pathogens as diverse as Toxoplama gondii, West Nile virus, Mycobacterium tuberculosis, herpes simplex virus, Trypanosoma cruzi, Cryptococcus neoformans, Chlamydia trachomatis, Listeria, and plasmodia. In human cohorts, individuals carrying the defective CCR5Delta32 allele present an increased susceptibility to flavivirus (West Nile virus and tickborne encephalitis virus). The selective pressures that led to the spread of loss-of-function CCR5 mutations in humans (CCR5Delta32), and in mangabeys (CCR5Delta24) are not understood. SUMMARY: The recent availability of CCR5 antagonists has raised concern that genetic, biological, or chemical CCR5 knockout, although beneficial against some pathogens (i.e. HIV), could be deleterious for other processes implicated in pathogen response. The consequences of long-term pharmaceutical intervention on CCR5 should be carefully assessed through rigorous postmarketing surveillance.

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OBJECTIVES: Persons from sub-Saharan Africa (SSA) are increasingly enrolled in the Swiss HIV Cohort Study (SHCS). Cohorts from other European countries showed higher rates of viral failure among their SSA participants. We analyzed long-term outcomes of SSA versus North Western European participants. DESIGN: We analyzed data of the SHCS, a nation-wide prospective cohort study of HIV-infected adults at 7 sites in Switzerland. METHODS: SSA and North Western European participants were included if their first treatment combination consisted of at least 3 antiretroviral drugs (cART), if they had at least 1 follow-up visit, did not report active injecting drug use, and did not start cART with CD4 counts >200 cells per microliter during pregnancy. Early viral response, CD4 cell recovery, viral failure, adherence, discontinuation from SHCS, new AIDS-defining events, and survival were analyzed using linear regression and Cox proportional hazard models. RESULTS: The proportion of participants from SSA within the SHCS increased from 2.6% (<1995) to 20.8% (2005-2009). Of 4656 included participants, 808 (17.4%) were from SSA. Early viral response (6 months) and rate of viral failure in an intent-to-stay-on-cART approach were similar. However, SSA participants had a higher risk of viral failure on cART (adjusted hazard ratio: 2.03, 95% confidence interval: 1.50 to 2.75). Self-reported adherence was inferior for SSA. There was no increase of AIDS-defining events or mortality in SSA participants. CONCLUSIONS: Increased attention must be given to factors negatively influencing adherence to cART in participants from SSA to guarantee equal longer-term results on cART.

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The 69 insertion and Q151M mutations are multi-nucleoside/nucleotide resistance mutations (MNR). The prevalence among 4078 antiretroviral therapy (ART)-experienced individuals was <1.3%. Combined ART fully prevented MNR in subtype B infections. Case-control studies were performed to identify risk factors. Control subjects were patients with ≥ 3 thymidine-analogue mutations. The 69 insertion study (27 control subjects, 14 case patients) identified didanosine exposure as a risk (odds ratio, 5.0 per year; P = .019), whereas the Q151M study (which included 44 control subjects and 25 case patients) detected no associations. Following detection, individuals with Q151M tended to have lower suppression rates and higher mortality rates, relative to control subjects. Additional studies are needed to verify these findings in non-subtype B infections.

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Biocides are widely used for domestic hygiene, agricultural and industrial applications. Their widespread use has resulted in their introduction into the environment and raised concerns about potential deleterious effects on aquatic ecosystems. In this study, the toxicity of the biocides triclosan, penconazole and metalaxyl were evaluated with the freshwater bacterium Caulobacter crescentus and with a freshwater microbial community using a combination of single- and double-stain flow cytometric assays. Growth of C.  crescentus and the freshwater community were repressed by triclosan but not by penconazole or metalaxyl at concentrations up to 250 μM. The repressive effect of triclosan was dependent on culture conditions. Caulobacter crescentus was more sensitive to triclosan when grown with high glucose at high cell density than when grown directly in sterilized lake water at low cell density. This suggests that the use of conventional growth conditions may overestimate biocide toxicity. Additional experiments showed that the freshwater community was more sensitive to triclosan than C.  crescentus, with 10 nM of triclosan being sufficient to repress growth and change the phylogenetic composition of the community. These results demonstrate that isolate-based assays may underestimate biocide toxicity and highlight the importance of assessing toxicity directly on natural microbial communities. Because 10 nM of triclosan is within the range of concentrations observed in freshwater systems, these results also raise concerns about the risk of introducing triclosan into the environment.