Search

Close

Articles That Use the Category Name:

Medical Specialties / Infectious Diseases


Vaccination Reduces Risk of Alzheimer's Disease, Parkinson's Disease, and Other Neurodegenerative Disorders

Abstract: Neurodegeneration is an increasing problem of aging. Alzheimer's Disease (AD) and Parkinson's Disease (PD) are the most frequent forms of age-related neurodegeneration. Infectious diseases, in general, confer a risk of AD. Influenza and pneumonia vaccinations reduce risk of AD. Being vaccinated against pneumonia between ages 65-75 is associated with a reduction in the risk of AD afterwards. Protection against bacterial and viral infection is beneficial to the brain since these infections may activate dormant herpes simplex type 1 (HSV-1) and herpes zoster virus (HZV). HSV-1 and HZV may interact to trigger AD. Shingles (HZV) vaccine Zostavax reduces risk of AD and PD. This finding is consistent with the link between viruses and neurodegeneration. Herpes virus-induced reactivation of embryologic pathways silenced at birth could be one of the pathologic processes in AD and PD. Once embryologic reactivation has occurred in the brain of an older person and AD or PD develops, this complex process relentlessly destroys the protective mechanism it created in utero. Unanswered question: Are the AD-risk-reducing effects of flu, pneumonia, and shingles vaccinations cumulative? ... Read more

Clinical Features and Outcomes of Patients with COVID-19 After Discharge: A Retrospective, Multi-center Study

Abstract: Background. The follow-up data of discharged patients with coronavirus disease 19 (COVID-19) have not yet been fully analyzed and reported. This study aimed to evaluate the clinical features, test results, and outcomes of COVID-19 patients after discharge. Methods. 149 COVID-19 patients with follow-up data after discharge were included. Post-hospitalization data related to clinical features and outcomes were obtained by following the patients up to 6 weeks. Results. The COVID-19 patients were followed for a median of 28.0 days (range of 22 days to 42 days) after discharge from hospital. At the end of follow-up, four patients (2.7%) still had cough. The proportions of leukopenia and lymphopenia were 7.4% and 4.7%, respectively. The proportions of ALT, AST, and Cr abnormalities were 26.2%, 6.0%, and 0%, respectively. Abnormal chest CT was detected in 94 (63.1%) patients, including 14 (9.4%) unilateral pneumonia and 80 (53.7%) bilateral pneumonia. However, the proportion of chest CT abnormality significantly decreased compared to that at the time of admission. Conclusions: One month after discharge, few patients with COVID-19 had clinical symptoms; however, a substantial proportion of COVID-19 patients harbored abnormal laboratory and radiological examinations. Moderately long-term medical follow-up would justifiably benefit COVID-19 patients after discharge. ... Read more

Risk Factors for Fatal Outcome of Hospitalized Patients with COVID-19

Abstract: Background. Few studies reported the risk factors of fatal outcome of hospitalized patients with coronavirus disease 2019 (COVID-19). We aimed to identify the independent risk factors associated with fatal outcome of hospitalized COVID-19 patients. Methods. The clinical data of 109 consecutive COVID-19 patients including 40 (36.7%) common cases and 69 (63.3%) severe cases were included and analyzed. Results: Multivariate regression analysis indicated that platelets (PLT, OR, 0.988; 95% CI, 0.978-0.998; P=0.017) and C-reactive protein (CRP) (OR, 1.047; 95% CI, 1.026-1.068; P<0.001) levels were the independent risk factors of fatal outcome in COVID-19 patients. The optimal cut-off value of PLT counts for predicting fatal outcome was 161×109/L with the area under receiver operating characteristic curve (AUROC) of 0.824 (95% CI, 0.739-0.890). The optimal cut-off value of CRP for the prediction of fatal outcome was 46.2 mg/L with the AUROC of 0.954 (95% CI, 0.896-0.985). The CRP levels had higher predictive values for fatal outcome than PLT (P=0.016). The cumulative survival rate was significantly higher in patients with PLT>161×109/L compared with patients with PLT≤161×109/L (89.4% vs. 12.5%, log-rank test χ2=72.17; P<0.001). Survival rate of COVID-19 patients was prominently higher in CRP≤46.2 mg/L patients compared with patients with CRP>46.2 mg/L (95.9% vs. 22.9%, log-rank test χ2=77.85; P<0.001). Conclusions. PLT counts and CRP levels could predict fatal outcome of hospitalized COVID-19 patients with relatively high accuracy. ... Read more

Dynamic Differences of Immunological Parameters Between Severe and Non-severe COVID-19 Patients

Abstract: Objective. We aimed to compare the dynamic differences of immunological parameters between severe and non-severe COVID-19 patients. Methods. The cytokine profiles and lymphocyte subsets of 664 patients with COVID-19 (31 severe cases and 633 non-severe cases) were longitudinally analyzed. Results. Compared with non-severe cases, severe cases had a higher age (64 vs. 40 years, p<0.001), more common comorbidity (74.2% vs. 20.5%, p<0.001), and lymphopenia (0.7 vs. 1.4×109/L, p <0.001). Severe cases had markedly higher levels of IL-6, IL-8, and IL-10 from baseline to 35 days after admission than non-severe cases (p<0.001). No significant differences were observed in the dynamic levels of IL-1β, IL-2, IL-4, IL-5, IL-12, IL-17, TNF-α, IFN-α, and IFN-γ between severe and non-severe COVID-19 patients (p>0.05). The absolute counts of lymphocytes, CD3+ T cells, CD4+ T cells, CD8+ T cells, and CD45+ T cells were markedly lower in severe patients with COVID-19 compared with those in non-severe patients from baseline to 35 days after admission (p<0.001). No significant differences were observed in the dynamic levels of white cells count, CD19+ B cells count, and NK cells count between severe and non-severe COVID-19 patients (p>0.05). The decrease of T lymphocyte subsets reached its peak at day 1 to 3 after admission, and they gradually increased in the non-severe group, but sustained at low levels in the severe group at day 4 to 35 after admission. Conclusion. The dynamic changes of cytokine profiles and T lymphocyte subsets are related with the severity of COVID-19. ... Read more

Efficacy of Remdesivir for COVID-19

Abstract: Remdesivir is a broad-spectrum antiviral agent. With the rapid spread of Coronavirus disease 2019 (COVID-19) globally, remdesivir is taking the spotlight for COVID-19 treatment. Despite the promising signs of anti-CoV activity in several preclinical and clinical studies, more data of remdesivir in the treatment of COVID-19 is still needed for evaluating its efficacy. ... Read more

Clinical Management and Control of COVID-19 Infection: A Review

Abstract: In late December 2019, COVID-19 was first identified in Wuhan, China and resulted in a formidable outbreak in provinces and cities in China that became a pandemic. The outbreak likely began as several cases caused by probable zoonotic transmission, followed by human-to-human transmission via droplets or contact with infected bodily fluids or contaminated items. COVID-19 mainly affects the lower respiratory tract and manifests as pneumonia in human, and severely affected patients may have multiple organ dysfunction syndrome. Despite recent progress in vaccine development, the management of multiple organ failure caused by immune injury is mainly supportive. COVID-19 is more contagious than SARS and MERS, although it has a lower mortality rate. The 2019 outbreak of COVID-19 has been classified by the WHO as a Public Health Emergency of International Concern, which has drawn attention to the challenge of the disease and caused questioning of scientific strategies for preventing infection and improving clinical outcomes. This article reviews the latest developments on transmission and clinical management and control of COVID-19 infection. ... Read more

Serum HBV RNA Levels Predict Significant Liver Fibrosis in Patients with Chronic HBV Infection

Abstract: Background and Aim. Recently, several studies demonstrated that serum HBV RNA levels were associated with liver disease progression in patients with chronic hepatitis B virus (HBV) infection. This study aimed to determine whether serum HBV RNA levels were correlated with liver fibrosis. Methods. 319 treatment-naïve patients with chronic HBV infection were included. The correlation between serum HBV RNA levels and liver histological fibrosis stages was analyzed, and calculations of the area under the receiver operating curve (AUROC) were performed for serum HBV RNA. Results. Serum HBV RNA levels were an independent predictor for significant liver fibrosis both in HBeAg-positive patients (OR=0.514, p<0.001) and HBeAg-negative patients (OR=3.574, p<0.001). In 153 HBeAg-positive patients, HBV RNA had a better diagnostic performance than APRI and FIB-4 (AUROC of 0.77, 0.66, and 0.66 for HBV RNA, APRI, and FIB-4, respectively; p=0.045 for HBV RNA vs. APRI; p=0.043 for HBV RNA vs. FIB-4) for the diagnosis of significant liver fibrosis. In 166 HBeAg-negative patients, HBV RNA also had a better diagnostic performance than APRI and FIB-4 (AUROC of 0.78, 0.68, and 0.62 for HBV RNA, APRI, and FIB-4, respectively; p=0.036 for HBV RNA vs. APRI; p=0.003 for HBV RNA vs. FIB-4) for the diagnosis of significant liver fibrosis. Conclusion. Serum HBV RNA levels were a more accurate noninvasive test than APRI and FIB-4 for the diagnosis of significant liver fibrosis in treatment-naïve patients with chronic HBV infection. ... Read more

Growth Arrest or Drug Target Inactivity Is Not Sufficient for Persister Formation in E. coli

Abstract: Persisters are a subpopulation of slow-growing or nondividing cells that are tolerant to antibiotics and are thought to be involved in persistent infections. The development of antibiotic tolerant phenotype is thought to be due to antibiotic target inactivity and is closely associated with growth arrest. While growth arrest and antibiotic target inactivity are widely believed to be important for persister formation, there have been inconsistent results and it has been difficult to determine whether growth arrest or antibiotic target inactivity is necessary or sufficient for persister formation. To address these questions, we used a novel approach to create antibiotic target inactivation via promoter swap to knock down quinolone drug target DNA gyrase subunit A (GyrA), as well as growth arrest via CRISPR interference to block key cell division protein (FtsZ) and a key ribosomal protein L28 (RpmB). Growth dynamics, relative target gene expression, cellular ATP levels and persister formation in the GyrA, FtsZ, and RpmB knockdown strains were compared with the control growing bacteria. Surprisingly, we found that the strains that had growth arrest induced by FtsZ or RpmB knockdown did not induce persister formation. Similarly, knockdown of GyrA, a quinolone drug target, did not induce persister cells tolerant to levofloxacin. In addition, ATP levels, a measure of cellular metabolism, were not reduced but increased in the GyrA, FtsZ, and RpmB knockdown strains compared with the control strain. Thus, we conclude that growth arrest or target inactivation is not sufficient to produce persister phenotype as commonly assumed and that cellular ATP levels did not correlate with persister formation. Further studies are needed to better understand how persisters are formed for improved treatment of persistent infections. ... Read more

Identification of a Novel Gene argJ Involved in Arginine Biosynthesis Critical for Persister Formation in Staphylococcus aureus

Abstract: Staphylococcus aureus can cause both acute and recurrent persistent infections such as peritonitis, endocarditis, abscesses, osteomyelitis, and chronic wound infections. Effective treatments to treat persistent disease are paramount. However, the mechanisms of S. aureus persistence are poorly understood. In this study, we performed a comprehensive and unbiased high-throughput mutant screen against a transposon-insertion mutant library of S. aureus USA300 and focused on the role of argJ encoding an acetyltransferase in the arginine biosynthesis pathway, whose transposon insertion caused a significant defect in persister formation using multiple drugs and stresses. Genetic complementation and arginine supplementation restored persistence in the argJ transposon insertion mutant while generation of mutations on the active site of the ArgJ protein caused a defect in persistence. Quantitative RT-PCR analysis showed that the genes encoded in the arg operon were over-expressed under drug stressed conditions and in stationary phase cultures. In addition, the argJ mutant had attenuated virulence in both mouse and C. elegans. Our studies identify a new mechanism of persistence mediated by arginine metabolism in S. aureus. These findings provide not only novel insights about the mechanisms of S. aureus persistence but also offer novel therapeutic targets that may help to develop more effective treatment of persistent S. aureus infections. ... Read more

Identification of Essential Oils with Strong Activity Against Stationary Phase Uropathogenic Escherichia coli

Abstract: Escherichia coli is the most dominant pathogen causing urinary tract infections (UTIs), but the current most frequently prescribed antibiotics do not always effectively cure the infection due to quiescent persister bacteria, which present a treatment challenge because of frequent relapse. While it has been reported that some essential oils have antimicrobial activity against growing E. coli, the activity of essential oils against the non-growing stationary phase E. coli which is enriched in persisters has not been investigated. In this study, we evaluated the activity of 140 essential oils against stationary phase uropathogenic E. coli UTI89 and identified 39 essential oils at 0.5% concentration, 8 essential oils at 0.25% concentration, and 3 essential oils at 0.125% concentration to have high activity against stationary phase E. coli. Among the top eight essential oils, Oregano showed higher activity than the known persister drug tosufloxacin. The other top four hits including Allspice, Bandit thieves, Cinnamon bark, and Syzygium aromaticum could eradicate stationary phase E. coli at a low concentration of 0.25% after three- or five-day exposure, while Health shield, Cinnamon leaf, and Clove bud were found to be active at a higher concentration. In Oregano essential oil drug combination studies with common UTI antibiotics, Oregano plus quinolone drugs (tosufloxacin, levofloxacin, and ciprofloxacin) completely eradicated all stationary phase E. coli cells, partially enhanced the activity of nitrofurantoin, but had no apparent enhancement for fosfomycin, meropenem, and cefdinir. Our findings may facilitate the development of more effective treatments for persistent UTIs. ... Read more

Close
Close
E-mail It
Close