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1.
The cholinergic anti-inflammatory pathway (CAP) refers to the anti-inflammatory effects mediated by the parasympathetic nervous system. Existence of this pathway was first demonstrated when acetylcholinesterase inhibitors showed benefits in animal models of sepsis. CAP functions via the vagus nerve. The systemic anti-inflammatory effects of CAP converges on the α7 nicotinic acetylcholine receptor on splenic macrophages, leading to suppression of pro-inflammatory cytokines and simultaneous stimulation of anti-inflammatory cytokines, including interleukin 10. CAP offers a novel mechanism to mitigate inflammation. Electrical vagal nerve stimulation has shown benefits in patients suffering from rheumatoid arthritis. Direct agonists like nicotine and GTS-1 have also demonstrated anti-inflammatory properties in models of sepsis and acute respiratory distress syndrome, as have acetylcholinesterase inhibitors like Galantamine and Physostigmine. Experience with coronavirus disease 2019 (COVID-19) induced acute respiratory distress syndrome indicates that immunomodulators have a protective role in patient outcomes. Dexamethasone is the only medication currently in use that has shown to improve clinical outcomes. This is likely due to the suppression of what is referred to as a cytokine storm, which is implicated in the lethality of viral pneumonia. Nicotine transdermal patch activates CAP and harvests its anti-inflammatory potential by means of an easily administered depot delivery mechanism. It could prove to be a promising, safe and inexpensive additional tool in the currently limited armamentarium at our disposal for management of COVID-19 induced acute hypoxic respiratory failure.  相似文献   
2.
BackgroundEpstein-Barr virus (EBV) is a member of the herpesvirus family that is known to ubiquitously infect people worldwide. However, the actual prevalence of EBV infection in diseased patients in Nigeria, remains unknown. This study was thus conducted to ascertain the true prevalence.MethodsA systematic review and meta-analysis of published data was conducted according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Electronic databases including PubMed, Scopus, ScienceDirect, and Google Scholar were searched for studies reporting the occurrence of EBV infection among patients with established diseases. Studies were included if they assessed EBV infection in diseased patients in Nigeria. Data were extracted and subsequently analysed using R software. Funnel plot and Egger's regression test was used to assess publication bias, while JBI prevalence tool was used to assess study quality.ResultsA total of 13 studies covering 228 cases of EBV infection among 1157 diseased patients were included. Summary estimates were computed using random-effects model. The pooled prevalence of EBV infection was 20.3% (95% CI: 10.8–34.9, I2 ?= ?92.26, p ?< ?0.001). When stratified according to the type of disease, higher estimates were obtained for patients suffering from Kaposi's sarcoma (98.7%, 95% CI: 82.2–99.9) and Nasopharyngeal malignancy (85.7%, 95% CI: 70.0–93.9). A prevalence of 13.4% (95% CI: 6.0–27.4) and 12.2% (95% CI: 4.8–27.8) was derived for the most reported patient populations, lymphoma and HIV, respectively.ConclusionThis first meta-analysis on the prevalence of EBV among Nigerian patients suffering from various diseases reveals a prevalence that emphasises the need to routinely monitor EBV infection in all EBV-associated diseases in Nigeria.  相似文献   
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Purpose: The purpose of this study was to examine the effect of prostate cancer educational program on the level of knowledge and intention to screen for prostate cancer among Jordanian men in Amman. Methods: A quasi-experimental, with nonequivalent control group design was used. 154 participants were randomly assigned to the intervention and control groups.  Level of Knowledge and intention to screen were measured at baseline and at 1 month after the application of the prostate cancer educational program. Independent sample t-test was used to analyze the data. Results: The results showed statistically significant change in the mean knowledge scores (8.7), p < 0.001 and the mean of intention to screen scores (3.71), p < 0.001, after 1 month from the application of the educational program in the experimental group compared to the control group. Conclusion: Implementing prostate cancer educational programs help enhance knowledge and intention to screen among Jordanian men.  相似文献   
4.
Objective: Gastric cancer is the third-leading cause of cancer-related mortality and the fifth most common cancer globally. Polyunsaturated fatty acids (PUFAs) are considered as functional ingredients that improve the efficacy of chemotherapeutic drugs. The aim of this study is to investigate the effect of PUFAs administration on matrix metalloproteinases (MMPs).

Methods: This study was designed as a randomized, double-blind trial. Thirty-four newly diagnosed patients with gastric cancer were randomly divided into two groups: control group (n?=?17) and case group (n?=17). Both groups received the same dose (75?mg/m2) of cisplatin. Control group received cisplatin plus placebo and the case group received cisplatin plus PUFAs [3600?mg/day, for three courses (each course included 3 weeks)]. The mRNA and protein expression of MMPs determined by real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC), respectively.

Results: The relative gene expression of MMP-1 and MMP-9 was significantly lower in case group than control. The protein expression of MMP-1 and MMP-9 was significantly lower in case group than control.

Conclusion: According to the results of this study, PUFAs reduced the expression of MMPs in gastric cancer cells. It seems that PUFAs may have an inhibitory effect on invasion and metastasis of gastric cancer cells.  相似文献   

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How to cite this article: Kumar A, Kumar N, Lenin D, Kumar A, Ahmad S. Second-degree Heart Block Caused by Itolizumab-induced Infusion Reaction in COVID-19. Indian J Crit Care Med 2021;25(4):474–475.

Sir,Itolizumab, an anti-CD6 humanized IgG1 monoclonal antibody, binds to domain-1 of CD-6 that is responsible for priming, activation, and differentiation of T-cells.[1] It significantly reduces T-cell proliferation along with substantial downregulation of the production of cytokines/chemokines.1 It was approved for moderate to severe chronic plaque psoriasis in 2013. However, it has recently been approved by the Drug Controller General of India for emergency use in India for the treatment of cytokine release syndrome in moderate to severe acute respiratory distress syndrome patients due to COVID-19.2 Here, we report a case of life-threatening infusion-related hypersensitivity reaction of itolizumab.A 65-year-old male COVID-19 patient got admitted to the intensive care unit (ICU) with complaints of shortness of breath and cough without any history of known disease. However, the baseline electrocardiogram (ECG) done in the ICU was suggestive of left bundle branch block (LBBB) (Fig. 1A). The patient was supported through noninvasive ventilation (NIV) and was started on remdesivir, dexamethasone, low-molecular-weight heparin, antibiotics, and other supportive treatment as per our institutional standard protocol. The patient was maintaining on continuous positive airway pressure mode of NIV with a fraction of inspired oxygen (FiO2) of 0.5 on the third day of ICU admission. Among the laboratory markers, the total leucocyte counts were raised (12,000/μL) with decreased lymphocytes (3.2%) and increased inflammatory markers (CRP, 320 mg/L; D dimer >20 μg/mL; LDH, 1694 U/L; IL6, 329 pg/mL). Serum electrolytes, renal function tests, liver function tests, and arterial blood gases were within acceptable limits. The patient was hemodynamically stable with a respiratory rate of 30 to 35/minute and a PO2/FiO2 ratio of 140. After taking informed written consent, inj. itolizumab was planned in this patient because of the increasing severity of the disease along with increased inflammatory markers. Inj. hydrocortisone 100 mg IV and inj. pheniramine 30 mg IV were given 30 minutes before itolizumab infusion. And 100 mg of itolizumab (Alzumab-L, Biocon Biologics) was diluted to 250 mL with normal saline and was started at 25 mL/hour. After about 20 minutes of infusion, the patient started complaining of shivering, sweating, and impending doom. The patient had sudden bronchospasm, and oxygen saturation dropped to 90%. ECG showed second-degree AV nodal block with an increased blood pressure of 180/110 mm Hg (Fig. 1B). The drug was immediately withdrawn and the patient was given a repeat dose of hydrocortisone and pheniramine along with other supportive measures. After sometime patients became alert and their respiratory symptoms were relieved. However, the second-degree heart block in ECG was persistent. ECHO was normal and troponin I was within normal limits while there was a slight increase in CPK-MB. The patient was observed closely and the ECG reverted to its previous state only after 24 hours. The patient was weaned from the ventilator in due course of time and put on face mask on the eighth day of stay.Open in a separate windowFigs 1A and B(A) Baseline ECG showing LBBB; (B) ECG showing second-degree AV nodal block after infusion reactionMost infusion reactions related to monoclonal antibodies are IgE mediated and are mild (grade 1 or 2) in nature.3 The incidence of severe (grade 3 or 4) reactions is generally low. The reported infusion-related reactions to itolizumab are chills/rigors (common), nausea, flushing, urticaria, cough, hypersensitivity, pruritus, rash, wheezing, dyspnea, oxygen desaturation, dizziness, headache, and hypertension. In our case, itolizumab infusion leads to a grade 4 reaction causing a persistent second-degree heart block for about 24 hours. Among the monoclonal antibodies, rituximab is most notorious for causing infusion reactions.4 There are only a few reports of cardiac arrhythmias (monomorphic VT, supraventricular tachycardia, trigeminy, and irregular pulse) during therapeutic infusion of rituximab,5 and there is no reported case of cardiac arrhythmia during itolizumab infusion. In our case, the patient was having LBBB and was on a QT prolonging drug (remdesivir), which might be a predisposing factor for the occurrence of second-degree heart block during infusion reaction. Premedications (e.g., antipyretics, antihistamines, and steroids) are recommended before the administration of some chemotherapeutic agents and monoclonal antibodies. These drugs should never be given as IV bolus and should always be given slowly in an infusion. Baseline assessments including vital signs and cognition should be documented carefully before the start of treatment and all the emergency equipment and drugs should be kept ready. Grade 3 and 4 reactions should be managed promptly with epinephrine, antihistaminics, and steroids along with other symptomatic supportive measures. As itolizumab is approved for emergency use in COVID-19, risk-benefit ratio should be assessed before prescribing this and should be explained before taking consent for infusion.The patient provided written informed consent for the publication.  相似文献   
7.
Binding of the spike protein of SARS-CoV-2 to the human angiotensin-converting enzyme 2 (ACE2) receptor triggers translocation of the virus into cells. Both the ACE2 receptor and the spike protein are heavily glycosylated, including at sites near their binding interface. We built fully glycosylated models of the ACE2 receptor bound to the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. Using atomistic molecular dynamics (MD) simulations, we found that the glycosylation of the human ACE2 receptor contributes substantially to the binding of the virus. Interestingly, the glycans at two glycosylation sites, N90 and N322, have opposite effects on spike protein binding. The glycan at the N90 site partly covers the binding interface of the spike RBD. Therefore, this glycan can interfere with the binding of the spike protein and protect against docking of the virus to the cell. By contrast, the glycan at the N322 site interacts tightly with the RBD of the ACE2-bound spike protein and strengthens the complex. Remarkably, the N322 glycan binds to a conserved region of the spike protein identified previously as a cryptic epitope for a neutralizing antibody. By mapping the glycan binding sites, our MD simulations aid in the targeted development of neutralizing antibodies and SARS-CoV-2 fusion inhibitors.

Angiotensin-converting enzyme 2 (ACE2) is an enzyme that catalyzes the hydrolysis of angiotensin II into angiotensin (17) to counterbalance the ACE receptor in blood pressure control (1). A single transmembrane helix anchors ACE2 into the plasma membrane of cells in the lungs, arteries, heart, kidney, and intestines (2). The vasodilatory effect of ACE2 has made it a promising target for drugs treating cardiovascular diseases (3).ACE2 also serves as the entry point for several coronaviruses into cells, including SARS-CoV and SARS-CoV-2 (46). The binding of the spike protein of SARS-CoV and SARS-CoV-2 to the peptidase domain (PD) of ACE2 triggers endocytosis and translocation of both the virus and the ACE2 receptor into endosomes within cells (4). The human transmembrane serine protease 2, TMPRSS2, primes spike for efficient cell entry by cleaving its backbone at the boundary between the S1 and S2 subunits or within the S2 subunit (4). The structure of the ACE2 receptor in complex with the SARS-CoV-2 spike receptor binding domain (RBD) (79) reveals the major RBD interaction regions as helix H1 (Q24–Q42), a loop in a beta sheet (K353–R357), and the end of helix H2 (L79–Y83). With a 4-Å heavy-atom distance cutoff, 20 residues of ACE2 interact with 17 residues of the RBD, forming a buried interface of ∼1,700 Å2 (7).The structure of full-length ACE2 has been resolved in complex with B0AT1 (also known as SLC6A19) (9). B0AT1 is a sodium-dependent neutral amino acid transporter (10). ACE2 functions as chaperone for B0AT1 and is responsible for its trafficking to the plasma membrane of kidney and intestine epithelial cells (11). Although it was speculated that B0AT1 prevents ACE2 cleavage by TMPRSS2 and thus could suppress SARS-CoV-2 infection (9, 12), other studies showed that SARS-CoV-2 can infect human small intestinal enterocytes where ACE2 is expected to be in complex with B0AT1 (13).Both the ACE2 receptor and the spike protein are heavily glycosylated. Several glycosylation sites are near the binding interface (7, 9, 14, 15). Whereas the focus has largely been on amino acid interactions in the ACE2–spike binding interface (16, 17), the role of glycosylation in binding has been recognized (7, 1820). The extracellular domain of the ACE2 receptor has seven N-glycosylation sites (N53, N90, N103, N322, N432, N546, and N690) and several O-glycosylation sites (e.g., T730) (9, 14). Among ACE2 glycosylation sites, the only well-characterized position regarding the effect on the spike binding and viral infectivity is N90. It is known from earlier SARS-CoV studies that glycosylation at the N90 position might interfere with virus binding and infectivity (21). Also, recent genetic and biochemical studies showed that mutations of N90, which remove the glycosylation site directly, or of T92, which remove the glycosylation site indirectly by eliminating the glycosylation motif (NXT), increase the susceptibility to SARS-CoV-2 infection (22, 23).We use extensive molecular dynamics (MD) simulations to gain a detailed molecular-level understanding of how ACE2 glycosylation impacts the host–virus interactions. Glycosylation sites N90 and N322 of human ACE2 emerge as major determinants of its binding to SARS-CoV-2 spike. Remarkably, glycans at these sites have opposite effects, interfering with spike binding in one case, and strengthening binding in the other. Our findings provide direct guidance for the design of targeted antibodies and therapeutic inhibitors of viral entry.  相似文献   
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47,XYY syndrome is a sex chromosomal anomaly in men, which may be associated with infertility and has an incidence of 0.1% of male births. The clinical and paraclinical characteristics of men suffering from this anomaly have not been fully described. In this retrospective study, we present 37 cases of 47,XYY infertile men with sperm counts varying from normal to azoospermia, referred to the Genetics Laboratory at the Royan Institute, Iran. Thirteen individuals were mosaic and 24 non-mosaics. Non-mosaic patients were classified as azoospermic (nine cases) and normospermic/oligozoospermic men (15 cases). Two of the non-mosaic and three mosaic patients had secondary infertility. In addition, 13 of them underwent IUI, IVF or ICSI, and in seven cases, there was a biochemical pregnancy. The remaining 14 patients did not have ART. The 47,XYY syndrome is relatively unusual and can be missed clinically because of the lack of symptoms and of diverse phenotypes. Diagnosis of this aneuploidy can provide valuable data for counselling and early management of the patients who undergo fertility evaluation.  相似文献   
10.
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