Pharmacological actions and underlying mechanisms of Catechin: A review

Background: Catechin is a phytochemical and is a major component of our daily use beverages, which has shown great potential in improving general health and fighting against several medical conditions. Clinical studies have confirmed its effectiveness in conditions ranging from acute upper respiratory tract infection, neuroprotection, to cardio-protection effects. Though most studies relate their potential to anti-oxidative action and radical scavenging action, still the mechanism of action is not clearly understood. Objective: The present review article is focused on addressing various pharmacological actions and underlying mechanisms of catechin. Additionally, we will try to figure out the major adverse effect and success in trials with catechin and lead to a conclusion for its effectiveness. Methods: This review article is based on the recent/ most cited papers of PubMed and Scopus databases. Description: Catechin can regulate Nrf2 and NFkB pathways in ways that impact oxidative stress and inflammation by influencing gene expression. Other pathways like MAPKs and COMT and receptor tyrosine kinase are also affected by catechin and EGCG that alter their action and barge the cellular activity. This review article explored the structural aspect of catechin and its different isomers and analogs. It also evaluated its various therapeutic and pharmacological arrays . Conclusion: Catechin and its stereo-isomers have shown their effectiveness as anti-inflammatory, anti-diabetic, anti-cancer, anti-neuroprotective, bactericidal, memory enhancer, anti-arthritis, and hepato-protective mainly through its activity to alter the pathway by NF-κB, Nrf-2, TLR4/NF-κB, COMT, and MAPKs.

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Dynamics of the upper respiratory tract microbiota and its association with fatality in COVID-19 patients

10.21203/rs.3.rs-95239/v1 ◽

2020 ◽

Author(s):

Mingkun Li ◽

Lili Ren ◽

Yeming Wang ◽

Jiaxin Zhong ◽

Dingyu Zhang ◽

...

Keyword(s):

Respiratory Tract ◽

Strong Predictor ◽

Geographic Area ◽

Healthy Controls ◽

Upper Respiratory Tract ◽

Clinical Trial Registration ◽

Registration Number ◽

Oropharyngeal Swab ◽

Upper Respiratory ◽

Underlying Mechanisms

Abstract The pandemic of Coronavirus disease 2019 (COVID-19) is ongoing globally, which is a big challenge for public health. Alteration of human microbiota had been observed in COVID-19. However, it is unknown how the microbiota is associated with the fatality in COVID-19. We conducted metatranscriptome sequencing on 588 longitudinal oropharyngeal swab specimens collected from 192 COVID-19 patients recruited in the LOTUS clinical trial (Registration number: ChiCTR2000029308) (including 39 deceased patients), and 95 healthy controls from the same geographic area. The upper respiratory tract (URT) microbiota in COVID-19 patients differed from that in healthy controls, while deceased patients possessed a more distinct microbiota. Streptococcus was enriched in recovered patients, whereas potential pathogens, including Candida and Enterococcus, were more abundant in deceased patients. Moreover, the microbiota dominated by Streptococcus was more stable than that dominated by other species. In contrast, the URT microbiota in deceased patients showed a more significant alteration and became more deviated from the norm after admission. The abundance of Streptococcus on admission, particularly that of S. parasanguinis, was identified as a strong predictor of fatality by Cox and L1 regularized logistic regression analysis, thus could be used as a potential prognostic biomarker of COVID-19. The generalization of the results in other populations and underlying mechanisms needs further investigations.

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Prevalence and clinical course of upper airway respiratory virus infection in critically ill patients with hematologic malignancies

PLoS ONE ◽

10.1371/journal.pone.0260741 ◽

2021 ◽

Vol 16 (12) ◽

pp. e0260741

Author(s):

Jongmin Lee ◽

Seok Chan Kim ◽

Chin Kook Rhee ◽

Jaewoong Lee ◽

Jong Wook Lee ◽

...

Keyword(s):

Respiratory Tract ◽

Critically Ill ◽

Critically Ill Patients ◽

Respiratory Virus ◽

Upper Airway ◽

Hematologic Malignancies ◽

High Dose ◽

Upper Respiratory Tract ◽

Anti Cancer ◽

Upper Respiratory

Background The clinical significance of upper airway respiratory virus (RV) detection in patients with hematologic malignancies remains unclear. We aimed to investigate the association between upper airway RV detection and prognosis in critically ill patients with hematologic malignancies. Methods This retrospective observational study included 331 critically ill patients with hematologic malignancies who presented respiratory symptoms and their nasopharyngeal swab was tested using a multiplex PCR assay between January 2017 and December 2018. A logistic regression model was used to adjust for potential confounding factors in the association between assay positivity and in-hospital mortality. Results Among the 331 analyzed patients, RVs were detected in 29.0%. The overall mortality rates in the intensive care unit and hospital were 56.8% and 65.9%, respectively. Positive upper airway RV detection was associated with relapsed hematologic malignancies, higher level of C-reactive protein, and prior use of high dose steroids and anti-cancer chemotherapeutic drugs. Furthermore, it was independently associated with in-hospital mortality (adjusted odds ratio, 2.36; 95% confidence interval, 1.23 to 4.54). Among different RVs, parainfluenza virus was more prevalent among patients who died in the hospital than among those who survived (11.5% vs. 3.5%, P = 0.027). Conclusions RV detection in the upper respiratory tract was relatively common in our cohort and was significantly associated with a poor prognosis. Thus, it can be used as a predictor of prognosis. Moreover, RV presence in the upper respiratory tract should be examined in patients who have previously been prescribed with high dose corticosteroids and anti-cancer drugs.

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Probiotics to Prevent or Mitigate the Common Cold

Advances in Nutrition & Food Science ◽

10.33140/anfs/02/01/00004 ◽

2017 ◽

Vol 2 (1) ◽

Keyword(s):

Common Cold ◽

Health Benefit ◽

The United States ◽

Upper Respiratory Tract ◽

Acute Infections ◽

Growing Body ◽

Potential Benefits ◽

The Common ◽

Upper Respiratory ◽

Underlying Mechanisms

Upper respiratory tract infection, or the common cold, is a nonspecific term used to describe acute infections often caused by viruses. There are millions of cases of the common cold yearly in the United States. Probiotics are live microorganisms when administered in adequate amounts confer a health benefit on the host. Although the underlying mechanisms are still unclear, the application of probiotics shows promising activity in systemic immune modulations. There is now a growing body of evidence that suggests the potential benefits of probiotics in reducing the incidence and/or mitigating the symptoms associated with the common cold in otherwise healthy people of all ages.

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Prevalence and Clinical Course of Upper Airway Respiratory Virus Infection in Critically Ill Patients with Hematologic Malignancies

10.21203/rs.3.rs-31868/v1 ◽

2020 ◽

Author(s):

Jongmin Lee ◽

Seok Chan Kim ◽

Chin Kook Rhee ◽

Jaewoong Lee ◽

Jong Wook Lee ◽

...

Keyword(s):

Respiratory Tract ◽

Critically Ill ◽

Critically Ill Patients ◽

Respiratory Virus ◽

Upper Airway ◽

Hematologic Malignancies ◽

High Dose ◽

Upper Respiratory Tract ◽

Anti Cancer ◽

Upper Respiratory

Abstract Background The clinical significance of upper airway respiratory virus (RV) detection in patients with hematologic malignancies remains unclear. We aimed to investigate the association between upper airway RV detection and prognosis in critically ill patients with hematologic malignancies. Methods This retrospective observational study included 331 critically ill patients with hematologic malignancies who presented respiratory symptoms and their nasopharyngeal swab was tested using a multiplex PCR assay between January 2017 and December 2018. A logistic regression model was used to adjust for potential confounding factors in the association between assay positivity and in-hospital mortality. Results Among the 331 analyzed patients, RVs were detected in 29.0%. The overall mortality rates in the intensive care unit and hospital were 56.8% and 65.9%, respectively. Positive upper airway RV detection was associated with relapsed hematologic malignancies, higher level of C-reactive protein, and prior use of high dose steroids and anti-cancer chemotherapeutic drugs. Furthermore, it was independently associated with in-hospital mortality (adjusted odds ratio, 2.36; 95% confidence interval, 1.23 to 4.54). Among different RVs, parainfluenza virus was more prevalent among patients who died in the hospital than among those who survived (11.5% vs. 3.5%, P = 0.027). Conclusions RV detection in the upper respiratory tract was relatively common in our cohort and was significantly associated with a poor prognosis. Thus, it can be used as a predictor of prognosis. Moreover, RV presence in the upper respiratory tract should be examined in patients who have previously been prescribed with high dose corticosteroids and anti-cancer drugs.

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Biological and Epidemiological Features of Antibiotic-Resistant Streptococcus pneumoniae in Pre- and Post-Conjugate Vaccine Eras: a United States Perspective

Clinical Microbiology Reviews ◽

10.1128/cmr.00058-15 ◽

2016 ◽

Vol 29 (3) ◽

pp. 525-552 ◽

Cited By ~ 116

Author(s):

Lindsay Kim ◽

Lesley McGee ◽

Sara Tomczyk ◽

Bernard Beall

Keyword(s):

Streptococcus Pneumoniae ◽

Population Based ◽

Community Acquired Pneumonia ◽

Surveillance Program ◽

Upper Respiratory Tract ◽

Pneumococcal Infections ◽

Antibiotic Resistant ◽

Content Type ◽

Upper Respiratory ◽

Underlying Mechanisms

SUMMARYStreptococcus pneumoniaeinflicts a huge disease burden as the leading cause of community-acquired pneumonia and meningitis. Soon after mainstream antibiotic usage, multiresistant pneumococcal clones emerged and disseminated worldwide. Resistant clones are generated through adaptation to antibiotic pressures imposed while naturally residing within the human upper respiratory tract. Here, a huge array of related commensal streptococcal strains transfers core genomic and accessory resistance determinants to the highly transformable pneumococcus. β-Lactam resistance is the hallmark of pneumococcal adaptability, requiring multiple independent recombination events that are traceable to nonpneumococcal origins and stably perpetuated in multiresistant clonal complexes. Pneumococcal strains with elevated MICs of β-lactams are most often resistant to additional antibiotics. Basic underlying mechanisms of most pneumococcal resistances have been identified, although new insights that increase our understanding are continually provided. Although all pneumococcal infections can be successfully treated with antibiotics, the available choices are limited for some strains. Invasive pneumococcal disease data compiled during 1998 to 2013 through the population-based Active Bacterial Core surveillance program (U.S. population base of 30,600,000) demonstrate that targeting prevalent capsular serotypes with conjugate vaccines (7-valent and 13-valent vaccines implemented in 2000 and 2010, respectively) is extremely effective in reducing resistant infections. Nonetheless, resistant non-vaccine-serotype clones continue to emerge and expand.

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