Contriving multi-epitope vaccine ensemble for monkeypox disease using an immunoinformatics approach

The current global outbreak of monkeypox (MPX) disease, caused by Monkeypox virus (MPXV), has resulted in 16 thousand infection cases, five deaths, and has been declared a global health emergency of international concern by the World Health Organization. Given current challenges in the safety of existing vaccines, a vaccine to prevent MPX infection and/or onset of symptoms would significantly advance disease management. In this context, a multi-epitope-based vaccine could be a well-suited approach. Herein, we searched a publicly accessible database (Virus Pathogen Database and Analysis Resource) for MPXV immune epitopes from various antigens. We prioritized a group of epitopes (10 CD8+ T cells and four B-cell epitopes) using a computer-aided technique based on desirable immunological and physicochemical properties, sequence conservation criteria, and non-human homology. Three multi-epitope vaccines were constructed (MPXV-1–3) by fusing finalized epitopes with the aid of appropriate linkers and adjuvant (beta-defensin 3, 50S ribosomal protein L7/L12, and Heparin-binding hemagglutinin). Codon optimization and in silico cloning in the pET28a (+) expression vector ensure the optimal expression of each construct in the Escherichia Coli system. Two and three-dimensional structures of the constructed vaccines were predicted and refined. The optimal binding mode of the construct with immune receptors [Toll-like receptors (TLR2, TLR3, and TLR4)] was explored by molecular docking, which revealed high docking energies of MPXV-1–TLR3 (–99.09 kcal/mol), MPXV-2–TLR3 (–98.68 kcal/mol), and MPXV-3–TLR2 (–85.22 kcal/mol). Conformational stability and energetically favourable binding of the vaccine-TLR2/3 complexes were assessed by performing molecular dynamics simulations and free energy calculations (Molecular Mechanics/Generalized Born Surface Area method). In silico immune simulation suggested that innate, adaptive, and humoral responses will be elicited upon administration of such potent multi-epitope vaccine constructs. The vaccine constructs are antigenic, non-allergen, non-toxic, soluble, topographically exposed, and possess favourable physicochemical characteristics. These results may help experimental vaccinologists design a potent MPX vaccine.

Tolerance to Glutaraldehyde in Escherichia coli Mediated by Overexpression of the Aldehyde Reductase YqhD by YqhC

Glutaraldehyde is a widely used biocide on the market for about 50 years. Despite its broad application, several reports on the emergence of bacterial resistance, and occasional outbreaks caused by poorly disinfection, there is a gap of knowledge on the bacterial adaptation, tolerance, and resistance mechanisms to glutaraldehyde. Here, we analyze the effects of the independent selection of mutations in the transcriptional regulator yqhC for biological replicates of Escherichia coli cells subjected to adaptive laboratory evolution (ALE) in the presence of glutaraldehyde. The evolved strains showed improved survival in the biocide (11–26% increase in fitness) as a result of mutations in the activator yqhC, which led to the overexpression of the yqhD aldehyde reductase gene by 8 to over 30-fold (3.1–5.2 log2FC range). The protective effect was exclusive to yqhD as other aldehyde reductase genes of E. coli, such as yahK, ybbO, yghA, and ahr did not offer protection against the biocide. We describe a novel mechanism of tolerance to glutaraldehyde based on the activation of the aldehyde reductase YqhD by YqhC and bring attention to the potential for the selection of such tolerance mechanism outside the laboratory, given the existence of YqhD homologs in various pathogenic and opportunistic bacterial species.

Disturbances in Calcium and Zinc Homeostasis During Testicular Damage Induced by Citrus aurantifolia Juice in Wistar Rats

Infertility rate is high globally and in Nigeria. The reported spermicidal activity of Citrus aurantifolia juice (CAJ)and its popular consumption may be a contributing factor to the rise in male infertility. This study examined the effects ofCAJ on testis and evaluated the role of calcium and zinc in these effects. Twenty-eight male rats (200-220g) were groupedinto four (n=7). Group I (control) received 0.5ml normal saline, while groups II, III and IV received 600mg/kg, 900mg/kgand 1200mg/kg of CAJ, respectively, orally for 35 days. Sperm analysis, testicular histology, testicular zinc and calciumconcentrations were evaluated. The results showed a significant decrease (P < 0.001) in body weight and gonad-somaticindex (GSI) of the rats in group IV. No sperm cells were found in the sperm samples of all the treatment groups in contrastto control. There was a significant decrease (P < 0.001) in zinc concentration of group III and IV animals and a significantincrease (P < 0.001) in testicular calcium content of group III and IV animals. Derangement of testicular cyto-architecture,shrinkage or complete destruction of seminiferous tubules as well as absence of spermatogenic cells were observed in thetreatment groups. It was concluded that CAJ induced a destructive effect on testes of rats as evidenced by damaged testiculartissue, reduced gonado-somatic index, azospermia and disruption in testicular electrolyte homeostasis. It was concluded thatCAJ caused hypercalcaemia and hypozincaemia in the testicular tissue of the treated rats. Concurrently, CAJ also causeddamage to testicular histology, azospermia and decreased GSI. Citrus aurantifolia juice should be consumed with cautiondue to its potential to cause infertility in males.

A Case Report on Percutaneous Coronary Intervention in Chronic Total Occlusion by Retrograde Visualization

As bilateral approach is paramount in chronic total occlusions with retrograde flow, the use of two radial arteries, two femoral arteries or combination technique using one radial and one femoral artery will probably be increasingly reported in the near future. After puncture of opposite groin, a diagnostic 6 Fr catheter is used to intubate the ostium of the contralateral artery. By visualizing the distal vessel in multiple projections, contralateral injections help to direct the progression of the wire in the occluded segment towards the distal true lumen and confirm the intraluminal position of the wire after the occluded segment. We are reporting a case with chronic total occlusion where we used bilateral femoral access and simultaneous contrast injection to visualize retrograde flow in LAD while opening CTO through ante-grade pathway.

Pattern of dyslipidaemia among the Bangladeshi type 2 diabetic patients presented with acute coronary syndrome

Increasing prevalence of diabetes and its complications in the developing communities would pose a threat in respect to their existing health care service. An increased incidence of atherosclerosis in insulin-dependent diabetic patients has long been recognized. Hyperlipidaemia, a common finding in these patients, may be one of the contributing factors. The objective of our study is to find out the patterns of dyslipidaemia among the Bangladeshi patients with type-2 diabetes mellitus presented with acute coronary syndrome. This study was conducted in the department of cardiology of BIRDEM and Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh during the period of January 2009 to December 2009. A total of 100 patients were included in this study, according to the inclusion and exclusion criteria. Diabetes Mellitus and Acute Coronary Syndrome was diagnosed according to the guideline of American Diabetic Association and American College of Cardiology respectively. Among the respondents Mean±SD of fasting blood sugar and 2 hours ABF were 9.23±3.6mmol/L and 12.61±8.52mmol/L respectively. Mean±SD of HbA1C of the respondents was 7.23±2.12. Total cholesterol level <150mg/dl, 150-200mg/dl and >200mg/dl were 27.0%, 42.0% and 31.0% respectively. HDL cholesterol <40mg/dl and >40mg/dl were 76.0% and 24.0% respectively. LDL cholesterol <150mg/dl and >150mg/dl were 43.0% and 57.0% respectively. TG within 40 to 160mg/dl and >160mg/dl were 73.0% and 27.0% respectively, Mean±SD of Total Cholesterol, HDL Cholesterol, LDL Cholesterol and Triglyceride were 162.43±38.62, 37.41±8.59, 137.43±22.73 and 156.43±41.92mg/dl respectively.

Cardiovascular complications in patients with end stage renal disease on maintenance haemodialysis

This cross-sectional study was carried out at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka Medical College Hospital (DMCH), National Institute of Kidney Diseases & Urology (NIKDU) and Kidney Foundation from July 2005 to June 2007 to find the cardiovascular complications in end stage renal disease (ESRD) patients on maintenance haemodialysis. Patients of both sexes with age ranging from 18-59 years and getting at least 8 hours of haemodialysis per week for the last 3 months were enrolled in the study. A total of 126 such patients were included in the study. Among 126 patients 77(61.1%) developed some types of cardiovascular complications. In terms of type of complications 63.6% of the patients had LVH, 23.4% had ischemic heart disease (IHD) and 10.4% had congestive heart failure (CCF) and 2.6% cardiomyopathy. Over 96% patients were hypertensive, followed by 46.8% diabetics and 42.1% smokers. Presence of hypertension, diabetes, family history of diabetes and hypertension were observed to be significantly higher in patients who developed cardiovascular complications (p<0.05). It is deserved that cardiovascular complications (CVC) are very common in ESRD patients on maintenance haemodialysis (MHD). Poor control of blood pressure, low Haemoglobin level and poor glycaemic control are higher in ESRD patients on MHD and are possibly related to the development of cardiovascular complications.

Effect of Ingestion of Ethanol Extract of Garcinia Kola Seed on Erythrocytes in Wistar rats

The objective of this study is to investigate the effect of ingestion of crude ethanol extract of Garcinia kola seed on erythrocytes. Fifty male Wistar rats with average weight of 200g were divided into 5 treatment groups of 10 rats per group. Group A, served as the control and was fed with standard animal feed only while groups B, C, D and E which were the treatment groups, in addition were force-fed 2 g/kg/rat/day of the Ethanol extract of Garcinia kola seed for 1, 2, 3, and 4 weeks respectively by means of an endogastric tube and syringe. At the end of the experimental period for each group the animals were sacrificed and the erythrocyte number, packed cell volume (PCV), and heamogloin concentration values were determined. The result on analysis showed that erythrocyte-count, PCV and haemoglobin concentration values showed significantly decreased values [P < 0.05] between group B (week 1) and Group A, but groups C, D and E values showed a steady rise which were not significant [P < 0.05] when compared with Group A. None of the values fell below the normal physiological range of the experimental animals. This shows that Garcinia kola seed which has flavonoids as its active constituent has no long term significant toxicological implication with respect to the concentration given on the erythrocytes of mammals.

Sports and marfan syndrome: awareness and early diagnosis can prevent sudden death

Marfan syndrome is an autosomal dominant disorder of the connective tissues. Its major manifestations are in the cardiovascular, musculoskeletal, and ocular systems. Recognizing the phenotypic presentation of tall stature, long limbs and fingers, chest deformity, myopia, midsystolic click, and systolic or diastolic murmur can lead to early diagnosis. Morbidity and mortality are primarily caused by cardiovascular involvement. The goal of medical therapy is to retard the aortic root dilation that leads to sudden death from dissection or rupture. Surgical interventions for mitral valve regurgitation and resection of aortic aneurysms are highly effective. In addition, individuals with Marfan syndrome should be restricted from participation in certain sports.

Persistent pulmonary hypertension after maternal naproxen ingestion in a term newborn: a case report

Constricting effect of indomethacin on the ductus arteriosus of the fetus is well known. The fetal effects of other nonsteroid anti-inflammatory drugs (NSAIDs) like naproxen are not well reported. We report here a case of a 3,790-g term neonate who developed persistent pulmonary hypertension after birth with a closed ductus arteriosus. The mother admitted to taking naproxen sodium immediately prior to the birth of the infant. The course of illness was progressively better on conservative management. Like indomethacin, other NSAIDs can also cause premature closure of fetal ductus arteriosus, pulmonary hypertension, and life-threatening problems to the neonate. Patient education regarding over-the-counter pain medication during pregnancy should be emphasized.

The wandering pacemaker: intraperitoneal migration of an epicardially placed pacemaker and femoral nerve stimulation

A premature child with congenital complete heart block had an epicardial single-chamber pacemaker implanted at 2 days of age. At 21 months of age, while sitting or standing, the patient's right anterior thigh muscles contracted at her pulse rate. Surgical exploration revealed a free-floating pacemaker in her peritoneum. A new dual-chamber pacemaker was implanted into the abdominal wall with resolution of the child's symptoms.

Syncope recurrence in children: relation to tilt-test results

OBJECTIVES

To examine the intermediate-term outcome of children with syncope and its relationship to tilt test.

DESIGN

This was a retrospective study of 45 children. In 20, the tilt test was negative. Follow-up with respect to the recurrence of syncope was obtained via chart review, a mailed questionnaire, or telephone interview.

RESULTS

Follow-up data were available on 15 children whose tilt test was negative and on all 25 tilt-test positive children. Recurrent syncope was significantly greater in the positive-tilt children (13 of 25) than the negative-tilt children (2 of 15). There was no difference between the syncope-free group and the recurrent syncope group or between the tilt-positive and tilt-negative groups with respect to age at initial syncope, duration of symptoms, age at tilt test, and duration of follow-up. Children with a positive tilt test and those with recurrent syncope had more syncopal episodes before their evaluation than either the group with a negative tilt test or the group with no recurrent syncope, respectively.

CONCLUSIONS

Syncope may recur after either a negative or a positive tilt test. The recurrence rate, however, is higher for the tilt-positive children.

Serum electrolytes in children with neurocardiogenic syncope treated with fludrocortisone and salt

We examined the changes in serum electrolytes of patients with syncope treated with salt and fludrocortisone. The most significant change was an increase in serum bicarbonate concentration, with minimal alteration of sodium, potassium, and chloride concentrations; none was clinically significant.

The JT interval as a depolarization independent measurement of repolarization: lessons from catheter ablation of the Wolff-Parkinson-White syndrome

In patients with Wolff-Parkinson-White syndrome (WPW), preexcitation precludes accurate assessment of the ventricular repolarization by the QTc. In patients with long QT syndrome, it has been demonstrated that the JTc does not change when depolarization abnormalities develop. We hypothesized that this phenomenon should also be applicable to WPW patients. To test this, we assessed the surface ECG of 29 patients (16 males, 13 females) with WPW pre- and postablation. The QRS, QT, and JT intervals were measured pre- and postablation at 50 mm/s paper speed in leads II and V2. QTc and JTc were calculated according to Bazett's formula. The average age was 12.8 +/- 4.9 years (range 1.5-21). All patients had no residual preexcitation on postablation ECG. Early and late follow-up ECGs were obtained at 32 +/- 34 days and 388 +/- 197 days postablation, respectively. Both the QRS and the QTc intervals shortened significantly on the postablation versus preablation ECGs (QRS: 115 +/- 23 ms vs 89 +/- 15 ms, respectively; P < 0.0001), QTc: 454 +/- 26 vs 423 +/- 23, respectively; P < 0.0001). The preablation JTc interval did not change, postablation (319 +/- 21 vs 323 +/- 23, respectively; P > 0.2). Also, the JTc interval did not change between early and late follow-up, postablation. JTc is an independent measure of repolarization, not related to depolarization. JTc may be a useful tool in assessing repolarization in patients with WPW and other depolarization abnormalities.

Contribution of superior vena caval flow to total cardiac output in children. A Doppler echocardiographic study

BACKGROUND

After a cavopulmonary anastomosis, the superior vena caval flow, by virtue of being the effective pulmonary blood flow, is the most important factor influencing the systemic arterial saturation. Determination of the amount of this blood flow will allow a better understanding of the physiology of the circulation after this anastomosis. The purposes of this study were to determine the volumetric flow in the superior vena cava and to evaluate its contribution to the cardiac output as children grow.

METHODS AND RESULTS

Using two-dimensional and Doppler echocardiography, we measured the diameter of and mean flow velocities in the superior venae cavae and the pulmonary arteries of 145 healthy children. We calculated the volumetric flow in each vessel and determined the ratio of superior vena caval flow to total cardiac output. Cardiac output and superior vena caval flow increased with increasing age and body surface area. The superior vena caval flow accounted for 49% of cardiac output in newborn infants. This contribution increased to a maximum of 55% at the age of 2.5 years. Afterward, there was a slow decline in the ratio of superior vena caval-pulmonary arterial flow; it reached the adult value of 35% by 6.6 years of age.

CONCLUSIONS

There is a maturational change in the superior vena caval contribution to total cardiac output in children. This is most likely related to somatic growth and changes in body segment proportions. This flow maturation may explain the higher systemic saturation in infants compared with older children after cavopulmonary anastomosis.

Pulmonary/systemic flow ratio in children after cavopulmonary anastomosis

OBJECTIVES

This study attempted to provide a formula for calculation of the pulmonary/systemic flow ratio in children after bidirectional cavopulmonary anastomosis.

BACKGROUND

With the bidirectional cavopulmonary anastomosis, only the superior vena cava blood is oxygenated by the lungs. The inferior vena cava flow recirculates into the systemic circulation. The ratio of these flows will determine systemic arterial saturation.

METHODS

According to the Fick principle, 1) Systemic cardiac output (liters/min) = Pulmonary venous flow + Inferior vena cava flow; 2) Systemic blood oxygen transport (ml/min) = Pulmonary venous blood oxygen transport + Inferior vena cava blood oxygen transport. By substituting the first equation into the second, Pulmonary/systemic flow ratio = (Systemic saturation - Inferior vena cava saturation)/(Pulmonary venous saturation - Inferior vena cava saturation).

RESULTS

We applied the third formula to data obtained from 34 catheterizations in 29 patients after bidirectional cavopulmonary anastomosis. Mean [+/- SD] age at operation was 1.70 +/- 1.43 years, and mean age at catheterization was 2.95 +/- 1.65 years. The pulmonary/systemic flow ratio calculated for all 29 patients was 0.58 +/- 0.09. Of 17 patients with aortography, 10 had systemic to pulmonary collateral vessels. Patients with collateral vessels had a significantly higher pulmonary/systemic flow ratio (0.61 +/- 0.07 vs. 0.53 +/- 0.07, respectively, p < 0.02) and systemic saturation (88 +/- 4% vs. 82 +/- 4%, respectively, p < 0.002) than those without collateral vessels. The pulmonary/systemic flow ratio in those patients with no collateral vessels was similar to the previously reported echocardiographically derived superior vena cava/systemic flow ratio in normal children.

CONCLUSIONS

The pulmonary/systemic flow ratio after bidirectional cavopulmonary anastomosis can be calculated. Pulmonary blood flow in these patients determines systemic saturation and accounts for the majority of venous return in young children.

The fate of homograft conduits in children with congenital heart disease: an angiographic study

The use of homograft conduits in the repair of congenital heart disease is widely accepted. We reviewed the catheterization and angiographic data from 20 patients with homograft conduits. All conduits were to the pulmonary arteries. The age at operation was 4.7 +/- 5.6 years (mean +/- standard deviation) and at follow-up catheterization, 7.8 +/- 6.7 years. At implantation, conduit cross-sectional area and Z value were 219 +/- 96 mm2 and 3.5 +/- 1.8, respectively. At subsequent catheterization, the conduit diameters were measured in two projections at the shaft, annulus, valve opening, and insertion into the pulmonary artery. The transconduit gradient was 47 +/- 26 mm Hg. The cross-sectional areas were 149 +/- 56 mm2 at the shaft, 151 +/- 92 mm2 at the annulus, 108 +/- 116 mm2 at the valve opening, and 127 +/- 84 mm2 at the pulmonary artery insertion. The Z values were -0.9 +/- 2.5, -0.9 +/- 2.8, -3.8 +/- 4.0, and -2.0 +/- 3.4, respectively. The cross-sectional areas and the Z values at the levels of measurement were significantly smaller than the corresponding values at implantation. The change in cross-sectional areas and Z values exceeded what would be expected from growth alone. These data indicate that there is a decrease, with time, in the functional lumen of homograft conduits, and this may have implications for follow-up strategy after implantation.

Discrete subaortic stenosis after successful treatment of congenital aortic valve stenosis

Two cases of discrete subaortic obstruction which developed in a previously normal left ventricular outflow tract of patients with congenital valvar aortic stenosis are described. These examples emphasize the need for careful scrutiny of the etiology of recurrent postoperative left ventricular outflow tract obstruction.