Effects of Warming and Nutrient Enrichment on How Grazing Pressure Affects Leaf Litter–Colonizing Bacteria

In view of current scenarios of global environmental change, we investigated the effects of warming and nutrient addition (N and P) on the impact of detritivores on density and community composition of leaf litter-colonizing bacteria in a freshwater environment. Within 10 d, detritivorous amphipods (Gammarus pulex) reduced bacterial numbers at 10 degrees C and to a lesser degree at 15 degrees C. However, the detritivore-induced decrease in bacterial numbers was compensated for by nutrient addition. After 31 d of incubation, amphipods reduced bacterial numbers only at 15 degrees C, and nutrient addition did not counteract detritivore effects. Similarly, changes in bacterial numbers in response to nutrient addition were more pronounced at low temperature within 10 d, whereas nutrient effects were stronger at high temperature after 31 d of incubation. Thus, warming without detritivores did not affect bacterial numbers under low-nutrient conditions (10 d). When detritivores were present, warming increased bacterial density significantly just under high-nutrient conditions (P < 0.05). After 31 d of incubation, warming did not affect bacterial density in detritivore-free controls in both nutrient conditions and did not affect bacterial density in both nutrient conditions in the presence of detritivores. Warming exhibited a significant effect on the composition of litter-associated bacterial communities irrespective of nutrient load (P < 0.05), whereas nutrients had less consistent effects. We conclude that warming, and to a lesser degree nutrient enrichment, may have influence on grazer-induced changes in bacterial biofilm composition, whereas nutrient enrichment may mostly interfere with those processes that depend on bacterial density

Interactions between warming, nutrient enrichment and detritivores on litter decomposition and associated microbial decomposers

Leaf litter decomposition constitutes an important source of energy in many aquatic environments that is controlled by the joint action of microbial decomposers such as bacteria and fungi and also animal detritivores. In view of current scenarios of global environmental change, it is predicted that rapid temperature increases could directly affect most ecosystems including freshwaters. Additionally, human activities and industrial development have impacted water quality of many streams and rivers. In freshwater systems, eutrophication is a process, whereby excessive receive of inorganic nutrients, especially N and P, that may effect on leaf litter processing. In the present study, I investigated how warming, nutrient-addition (N and P) and detritivores, interact to affect multiple parameters associated with leaf decomposition. Investigations were carried out in the laboratory in two sets. For the studies presented here leaf litter Betula pendula (Birch) and the detritivore Gammarus pulex (Amphipoda) were chosen because of their numerical importance in northern temperate ecosystem. In the first set of experiments (Chapter I), I investigated the synergistic effects of warming and nutrient-addition (N and P) on the impact of amphipods on density and community composition of leaf litter-colonizing bacteria. I found that warming significantly exhibit stronger effects on the composition of litter-associated bacterial communities, irrespective of nutrient load but amphipods mediated warming-effects on bacterial community composition by selective feeding. In addition, Short-term effects of nutrient-addition on bacterial biofilm density were stronger than warming-effects but less pronounced so at increased temperatures. Alongside, Long-term effects of nutrient-addition on bacterial density were strongest, irrespective of environmental temperature. Additionally, nutrient-addition effectively compensated for biofilm reduction upon grazing by amphipods. In second set of experiments (chapter II), I proceeded to improve understanding of leaf litter decomposition process by comprehensive experiments to investigate how warming, nutrient-addition (N and P) and detritivores, interact to affect multiple parameters associated with leaf decomposition. These parameters included microbial (bacteria and fungi) biomass and community structure, decomposition rate and detritivore growth. I found that detritivores and nutrient-addition have strong effects on leaf litter decomposition rate but relative growth of detritivores does not increase with warming and nutrient addition. Additionally, bacterial biofilm density increases by both warming and nutrient-addition, but reduced by amphipod grazing-pressure and fungal biomass also appears to be stimulated by warming and nutrient-addition but also by amphipod presence. Moreover, litter-associated fungal composition were only slightly affected by warming or nutrient-addition, but strongly responded to selective feeding by amphipods and the community composition of bacterial colonizers on birch litter was also influenced by grazing pressure of amphipods and warming. In summary, this study provides new insights into the effect of simultaneous change in temperature and nutrient-load on microbial decomposers and also helps in better understanding of selective role of detritivores on bacterial and fungal communities on litter surfaces in freshwaters.Die Dekomposition von Laubstreu stellt in zahlreichen aquatischen Lebensräumen eine wichtige Energiequelle dar, die unter gemeinsamer Kontrolle von mikrobiellen Mineralisierern –Pilze und Bakterien– und detritivoren Tieren steht. Derzeitige Szenarien bezüglich globaler Umweltveränderungen berücksichtigend, hohe Erwärmungsraten könnten die meisten Ökosysteme, so auch Süßwässer, direkt beeinträchtigen. Zudem haben die industrielle Entwicklung und weitere menschliche Aktivitäten die Wasserqualität in zahlreichen Süßgewässern negativ beeinflusst. Eutrophierung ist z.B. durch übermäßige Zufuhr anorganischer Nährstoffe –insbesondere N und P– verursacht und könnte Dekomposition beeinträchtigen. In der vorliegenden Arbeit habe ich untersucht, wie Erwärmung und Nährstoffzufuhr (N und P) mit der Aktivität detritivorer Tiere interagieren, und wie dies sich auf verschiedene Parameter des Laubstreuabbaus auswirken. Diese Untersuchungen wurden im Rahmen zweier großvolumiger Laborstudien durchgeführt. Die Laubstreu von Betula pendula (Birke) und der Detritivor Gammarus pulex (Amphipoda) wurden hierzu aufgrund ihrer Bedeutung in nord-temperierten Ökosystemen gewählt. Im ersten Experiment (Kapitel I) untersuchte ich die synergistischen Effekte von Erwärmung und Nährstoffzufuhr (N und P) auf den Einfluss von Amphipoden auf die Dichte und Gemeinschaftszusammensatzung von Laubstreu besiedelnden Bakterien. Erwärmung hatte signifikant stärkere Effekte auf die Zusammensatzung der bakteriellen Gemeinschaft –unabhängig von der Nährstoffzufuhr– aber Amphipoden modulierten die Konsequenzen einer Erwärmung auf die bakterielle Gemeinschaft durch selektiven Fraß. Außerdem waren kurzzeitige Effekte der Nährstoffzufuhr auf bakterielle Dichten ausgeprägter als die einer Erwärmung, wurden jedoch durch zunehmende Temperaturen abgemildert. Langfristige Konsequenzen einer Nährstoffzufuhr auf bakterielle Dichten waren unabhängig von der Temperatur sehr ausgeprägt, und Nährstoffzufuhr kompensierte die Biofilmreduktion durch Amphipodenfraß. Mit dem zweiten Experiment (Kapitel II) versuchte ich detaillierter zu verstehen, wie die Dekomposition von Laubstreu durch die Interaktion von Erwärmung, Nährstoffzufuhr und die Aktivität von Detritivoren beeinflusst wird. Die hierzu untersuchten Parameter waren mikrobielle (pilzliche und bakterielle) Biomasse und Gemeinschaftszusammensetzung, Streuabbauraten und Wachstum der Detritivoren. Sowohl Detritivore als auch Nährstoffzufuhr beeinflussten den Streuabbau signifikant, aber Wachstumsraten der Detritivoren waren von Erwärmung oder Nährstoffzufuhr unabhängig. Auch die bakterielle Dichte nahm mit Erwärmung und Nährstoffzufuhr zu, wurde aber durch den Fraßdruck durch Amphipoden reduziert. Pilzliche Biomasse wurde ebenfalls durch Erwärmung und Nährstoffzufuhr, aber auch durch die Anwesenheit von Amphipoden, gefördert. Die Zusammensetzung der pilzlichen Gemeinschaft wurde von Erwärmung oder Nährstoffzufuhr nur geringfügig beeinflusst, reagierte aber auf selektiven Fraß der Amphipoden sehr stark, so wie auch de bakterielle Gemeinschaft durch Fraß und Erwärmung signifikant verändert wurde. Zusammenfassend liefert die vorliegende Arbeit neue Einblicke in gemeinsame Effekte gleichzeitiger Veränderungen in Temperatur und Nährstoffverfügbarkeit auf mikrobielle Mineralisierer und hilft dadurch, die Bedeutung detritivorer Tiere für bakterielle und pilzliche Gemeinschaften auf der Laubstreu in Süßwässern besser zu verstehen

Frequency of IL-10+CD19+ B cells in patients with prostate cancer compared to patients with benign prostatic hyperplasia

Background: The function of the immune system in prostate cancer (PC) might promote carcinogenesis. PC is a common cancer in men. Regulatory B cells (Bregs) are a new subtype of B cells that have suppressive roles in the immune system. Interleukin-10 (IL-10) is a dominant mediator of immune suppression released by Bregs. Objective: The purpose of this research was to examine the frequency of CD19+IL10+ B cells and IL-10 mRNA expression in patients with PC compared to patients with benign prostatic hyperplasia (BPH). Methods: Forty paraffin tissue samples from patients with PC and 32 paraffin tissue samples from patients with BPH were entered in this study. The immunohistochemistry staining was used to evaluate the pattern expression of CD19 and IL-10 markers. IL-10 mRNA expression in fresh tissue was determined by real time-polymerase chain reaction (RT-PCR). Results: The frequency of CD19+IL-10+ B cells and IL-10 mRNA expression in PC patients were significantly higher than patients with BPH. Also, there was no meaningful relationship between the frequency of IL-10+CD19+ B cells and gleason scores in patients with PC. Conclusions: Our findings suggested that frequency of IL-10+CD19+ B cells correlates with progressive stage of PC

Frequency of IL-10+CD19+ B cells in patients with prostate cancer compared to patients with benign prostatic hyperplasia

Background: The function of the immune system in prostate cancer (PC) might promote carcinogenesis. PC is a common cancer in men. Regulatory B cells (Bregs) are a new subtype of B cells that have suppressive roles in the immune system. Interleukin-10 (IL-10) is a dominant mediator of immune suppression released by Bregs. Objective: The purpose of this research was to examine the frequency of CD19+IL10+ B cells and IL-10 mRNA expression in patients with PC compared to patients with benign prostatic hyperplasia (BPH). Methods: Forty paraffin tissue samples from patients with PC and 32 paraffin tissue samples from patients with BPH were entered in this study. The immunohistochemistry staining was used to evaluate the pattern expression of CD19 and IL-10 markers. IL-10 mRNA expression in fresh tissue was determined by real time-polymerase chain reaction (RT-PCR). Results: The frequency of CD19+IL-10+ B cells and IL-10 mRNA expression in PC patients were significantly higher than patients with BPH. Also, there was no meaningful relationship between the frequency of IL-10+CD19+ B cells and gleason scores in patients with PC. Conclusions: Our findings suggested that frequency of IL-10+CD19+ B cells correlates with progressive stage of PC

Global prevalence of suicide in cancer patients: a systematic review and meta-analysis

Aim: Given that patients with cancer may commit suicide due to physical and mental problems, the present study objectives were to identify particular risk factors of different subgroup of patients including type of cancer, gender, age, type and time of suicide, and geographical region to facilitate early care and psychosocial support. Methods: A comprehensive review of databases including Embase, Scopus, PubMed, and Web of Science was conducted for original articles published in English from January 2000 to March 2022. It is based on the PRISMA checklist. Results: After reviewing 69 articles selected from 15 countries, the total prevalence rate of suicide among 34,157,856 patients with cancer was estimated 67,169, at 0.013 (95% CI, 0.008–0.021). The highest suicide prevalence was related to gastrointestinal cancer, estimated at 0.204 (95% CI, 0.161–0.255). A gender-based meta-analysis showed that the prevalence of suicide/suicidal ideation was higher among men, estimated at 0.013 (95% CI, 0.008–0.023) compared with women, at 0.006 (95% CI, 0.002–0.017). Conclusion: Based on study results, suicide-prevention strategies should be aimed at patients younger than 40 years of age to effectively resolve their mental health disorders and promote their self-efficacy in successful management of the disease

A Comparative Analysis of Clinical Characteristics and Laboratory Findings of COVID-19 between Intensive Care Unit and Non-Intensive Care Unit Pediatric Patients: A Multicenter, Retrospective, Observational Study from Iranian Network for Research in Viral

Introduction: To date, little is known about the clinical features of pediatric COVID-19 patients admitted to intensive care units (ICUs).&nbsp;Objective: Herein, we aimed to describe the differences in demographic characteristics, laboratory findings, clinical presentations, and outcomes of Iranian pediatric COVID-19 patients admitted to ICU versus those in non-ICU settings.&nbsp;Methods: This multicenter investigation involved 15 general and pediatrics hospitals and included cases with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection based on positive real-time reverse transcription polymerase chain reaction (RT-PCR) admitted to these centers between March and May 2020, during the initial peak of the COVID-19 pandemic in Iran.&nbsp;Results: Overall, 166 patients were included, 61 (36.7%) of whom required ICU admission. The highest number of admitted cases to ICU were in the age group of 1–5 years old. Malignancy and heart diseases were the most frequent underlying conditions. Dyspnea was the major symptom for ICU-admitted patients. There were significant decreases in PH, HCO3 and base excess, as well as increases in creatinine, creatine phosphokinase (CPK), lactate dehydrogenase (LDH), and potassium levels between ICU-admitted and non-ICU patients. Acute respiratory distress syndrome (ARDS), shock, and acute cardiac injury were the most common features among ICU-admitted patients. The mortality rate in the ICU-admitted patients was substantially higher than non-ICU cases (45.9% vs. 1.9%, respectively; p&lt;0.001).&nbsp;Conclusions: Underlying diseases were the major risk factors for the increased ICU admissions and mortality rates in pediatric COVID-19 patients. There were few paraclinical parameters that could differentiate between pediatrics in terms of prognosis and serious outcomes of COVID-19. Healthcare providers should consider children as a high-risk group, especially those with underlying medical conditions

Global prevalence of nosocomial infection: A systematic review and meta-analysis

Objectives: Hospital-acquired infections (HAIs) are significant problems as public health issues which need attention. Such infections are significant problems for society and healthcare organizations. This study aimed to carry out a systematic review and a meta-analysis to analyze the prevalence of HAIs globally.   Methods: We conducted a comprehensive search of electronic databases including EMBASE, Scopus, PubMed and Web of Science between 2000 and June 2021. We found 7031 articles. After removing the duplicates, 5430 studies were screened based on the titles/abstracts. Then, we systematically evaluated the full texts of the 1909 remaining studies and selected 400 records with 29,159,630 participants for meta-analysis. Random-effects model was used for the analysis, and heterogeneity analysis and publication bias test were conducted.   Results: The rate of universal HAIs was 0.14 percent. The rate of HAIs is increasing by 0.06 percent annually. The highest rate of HAIs was in the AFR, while the lowest prevalence were in AMR and WPR. Besides, AFR prevalence in central Africa is higher than in other parts of the world by 0.27 (95% CI, 0.22-0.34). Besides, E. coli infected patients more than other micro-organisms such as Coagulase-negative staphylococci, Staphylococcus spp. and Pseudomonas aeruginosa. In hospital wards, Transplant, and Neonatal wards and ICU had the highest rates. The prevalence of HAIs was higher in men than in women.   Conclusion: We identified several essential details about the rate of HAIs in various parts of the world. The HAIs rate and the most common micro-organism were different in various contexts. However, several essential gaps were also identified. The study findings can help hospital managers and health policy makers identify the reason for HAIs and apply effective control programs to implement different plans to reduce the HAIs rate and the financial costs of such infections and save resources

Optimization of extraction and physicochemical properties of gelatin from pangasius catfish (Pangasius sutchi) skin

In order to optimize the extraction of gelatin from pangasius catfish skin, a response surface method (RSM) involving a Central Composite Design (CCD) was applied. Four variables, namely NaOH concentration (0-0.3 N), acetic acid concentration (0.025-0.125 N), extraction time (2-4 h) and extraction temperature (40-80°C) were selected as independent variables for the optimization using RSM. The dependent variable was calculated by hydroxyproline recovery. The optimum conditions for extraction were produced by a pre-treatment of 0.2 N NaOH and 0.1 N acetic acid along with hot water extraction at 63.7°C for 2.41 h. The results showed that the predicted response by RSM (68.53%) closely matched the experimental response of 68.16%. The results indicated that the extracted gelatin possessed high gel strength (438 g) and high content of imino acid (proline and hydroxyproline) (18.01%) with a viscosity of 4.67 mPa s. The results showed that RSM was a great optimizing tool for extraction of gelatin from pangasius catfish skin. The gelatin was also proven to have significantly (p<0.05) higher quality of physicochemical properties than those from bovine skin gelatin

The Prevalence, Risk Factors, and Clinical Correlates of Erosive Esophagitis and Barrett’s Esophagus in Iranian Patients with Reflux Symptoms

Background. Erosive esophagitis (EE) and Barrett’s esophagus (BE) are the two important complications of gastroesophageal reflux disease. We aimed to investigate the prevalence of and the risk factors for EE and BE in an Iranian group of patients with reflux symptoms. We also examined the relationship between reflux symptoms and endoscopic findings. Methods. A total of 736 patients with gastroesophageal reflux disease (GERD) symptoms were enrolled and all underwent upper gastrointestinal endoscopy. Diagnosis of Barrett’s esophagus was confirmed by pathologic examination and Helicobacter pylori (H. pylori) infection was demonstrated by rapid urease test. Results. Two hundred eighty-three and 34 patients were found to have EE and BE, respectively. Multivariate analysis showed that hiatal hernia (P<0.001) and H. pylori infection (P<0.002) were the two significantly related risk factors for esophagitis. Only age was related to BE, with BE patients being more likely to be older (P<0.001) than others. Conclusions. Prevalence of EE and BE in Iranian reflux patients is similar to that seen in western countries. H. pylori infection and the presence of hiatal hernia may be strong risk factors for esophagitis as does older age for Barrett’s esophagus. Finally, reflux symptoms have no significant relationship with endoscopic findings