COVID-19 and cardiovascular manifestations

OBJECTIVE

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as COVID-19, a viral outbreak that started in December 2019, eventually lead to a worldwide pandemic. COVID-19 usually presents with flu-like symptoms, such as headaches, dry cough, fever, fatigue, myalgia, shortness of breath, diarrhea and loss of smell or taste. However, it can also have major effects on the cardiovascular system. Based on the available relevant literature, we aimed to elaborate the possible mechanisms influencing cardiovascular damage, myocardial injury and thromboembolic disease process in particular.

MATERIALS AND METHODS

After considering our inclusion and exclusion criteria, the systematic review included 8 studies in total.

RESULTS

In general, underlying cardiovascular diseases were associated with poorer clinical outcomes. This may be due to immunological dysregulation. The disease outcomes were also positively correlated with the severity of the disease, especially with myocardial injury. Thus, cardiac biomarkers, such as Troponin T, CK-MB and myoglobin could be utilized in prediction algorithms for deciphering the clinical outcome in COVID-19 patients.

CONCLUSIONS

Venous thromboembolisms were commonly encountered complications despite the administration of thromboprophylaxis, and they mostly presented as pulmonary embolisms, warranting the need for relevant investigations in hemodynamically unstable patients. However, more studies need to be conducted to better understand the mechanisms at play and the ensuing complications, to better treat COVID-19 patients.

Computer simulations of the electric interactions between the phospholipid head-groups and ionic admixtures in the membrane surface

Some phospholipids (e.g. lecithin) form a system of electric dipoles on the membrane surface layer. In the case of lecithin the positive dipole charge is located on the choline and the negative one on the phosphoric molecule group. These dipoles are arranged almost parallel to the membrane surface. Taking the dipole membrane structure as a base for further investigations, a computer model of the electrostatic interaction between the dipole system and the ionic admixture was investigated. The model presumes hexagonal centered or a rectangular flat geometry of the 121 dipoles distribution. The dipoles may rotate freely around round the motionless symmetry axis perpendicular to the system surface. The initial state is given by fixing the geometry of the dipole matrix and ionic admixture distribution. Subsequently this system underwent a computer simulation which consisted of a calculation of resultant force moments acting on each dipole caused by other dipoles and ions. These force moments lead the system to the equilibrium state (minimum of the binding energy). The minimum energy value of the dipoles system depends on concentration and charge of the admixtured ions. The results of repeated simulations indicate that the system achieve the least of all binding energy (the most stable equilibrium state) at 1.5% concentration of admixtured ions in case of ion charge equal to 1Q (where Q denotes arbitrary unit of ion charge) and at 2.5% concentration of admixtured ions in case of ion charge equal to 2Q. The calculated results are in a good agreement with the experimental.

3D H(aro)-NOESY-CH3NH and C(aro)-NOESY-CH3NH experiments for double labeled proteins

Precision in the determination of the 3D structures of proteins by NMR depends on obtaining an adequate number of NOE restraints. Ambiguity in the assignment of NOE cross peaks between aromatic and other protons is an impediment to high quality structure determination. Two pulse sequences, 3D H(aro)-NOESY-CH3NH and 3D C(aro)-NOESY-CH3NH, based on a modification of a technique for simultaneous detection of 13C-1H (of CH3) and 15N-1H correlations in one measurement, are proposed in the present work. These 3D experiments, which are optimized for resolution in the 13C and 15N dimensions, provide NOE information between aromatic protons and methyl or amide protons. CH2 moieties are filtered out and the CH groups in aromatic rings are selected, allowing their NOE cross peaks to be unambiguously assigned. Unambiguous NOEs connecting aromatic and methyl or amide protons will provide important restraints for protein structure calculations.

The use of autologous platelet-rich plasma (platelet gel) and autologous platelet-poor plasma (fibrin glue) in cosmetic surgery

The purpose of this study was to evaluate a new technique of harvesting and preparing autologous platelet gel and autologous fibrin glue (body glue) and to evaluate their effectiveness in stopping capillary bleeding in the surgical flaps of patients undergoing cosmetic surgery. A convenience sample of 20 patients ranging from 25 to 76 years of age undergoing cosmetic surgery involving the creation of a surgical flap were included in the study. The types of surgical procedures included face lifts, breast augmentations, breast reductions, and neck lifts. Platelet-poor and platelet-rich plasma were prepared during the procedure from autologous blood using a compact, tabletop, automated autologous platelet concentrate system (SmartPReP, Harvest Autologous Hemobiologics, Norwell, Mass.). The platelet-poor and platelet-rich plasma were combined with a thrombin-calcium chloride solution to produce autologous fibrin glue and autologous platelet gel, respectively. Capillary bed bleeding was present in all cases and effectively sealed within 3 minutes following the application of platelet gel and fibrin glue. The technique for making the solution and for evaluating its effectiveness in achieving and maintaining hemostasis during cosmetic surgical procedures is described. Autologous platelet gel and fibrin glue prepared by the automated concentrate system are compared with autotransfusor-prepared platelet gel and Tisseel (Baxter Healthcare Corp.), a commercially prepared fibrin sealant preparation.

Sensitivity enhancement of HCACO by using an HMQC magnetization transfer scheme

Previous theoretical calculations have demonstrated that the multiquantum relaxation rate of (1)H(alpha)-(13)C(alpha)(R(MQ)) is, on average, 1.3 +/- 0.4 or 1.7 +/- 0.6 times slower than the single-quantum relaxation rate of (13)C(alpha)(R(C)) for a sample with or without, respectively, amide protons. By taking advantage of this fact and by using the PEP sensitivity enhancement scheme, an HMQC version of the HCACO experiment has been developed. We demonstrate that this new experiment is 23 and 55% more sensitive than the original HSQC version of the HCACO experiment, at constant times of 7 and 27 ms, respectively, for a sample of the BC domain of the ciliary neurotrophic factor receptor protein dissolved in D(2)O at 20 degrees C.

The influence of permanent magnetic field therapy on wound healing in suction lipectomy patients: a double-blind study

The authors present their experience with the healing influence of permanent magnets on postoperative wounds. The responses of 20 patients who underwent suction lipectomy and postoperative negative magnetic field therapy were studied in a double-blind fashion. Magnets in the form of patches (10 patients) or sham magnet patches (10 patients) were placed over the operative region in each of the patients. Pain, edema, and discoloration (ecchymosis) were evaluated at 1, 2, 3, 4, 7, and 14 days postoperatively. Our results show that the treatment group had significant reductions in pain on postoperative days 1 through 7, in edema on days 1 through 4, and in discoloration on days 1 through 3 when compared with the control group. These results demonstrated that commercially available magnets have a positive influence on the postoperative healing process in suction lipectomy patients.

Community-based empowerment programme for families with a brain injured survivor: an outcome study

Rehabilitation of brain injured persons has been one of the challenges of the modern health care team. Brain injured persons' problems are termed complex and multiple, and may persist long after the acute management stage. Families caring for their brain-injured members are, however, ill prepared to face this long-term rehabilitation process. A previous study of an empowerment framework applicable among these Hong Kong Chinese families resulted in the development of a 52-item empowerment questionnaire with four interpretable factors (efficacy, knowledge, support and aspiration). This can also serve as a valid and reliable outcome measure of their empowerment efforts. As a follow-up of this development, an 8-week community-based empowerment programme was thus designed and implemented for a total of 50 family members in six repeated groups. Outcome indicators including empowerment questionnaire, psychological well-being, self-efficacy, subjective experience of the burdens in care-giving, and support systems were used to monitor changes in empowerment status during the periods of pre- and post-programme, and during the 3 month follow-up. The programmes were found to be effective in empowering family members in the four postulated empowering dimensions, and improving all other outcome measures. The follow-up studies reflect stability in empowerment, though there were no further improvement. From regression analysis, it was suggested that, for optimum empowerment to take place, important predictors included careers' education levels, age ranges and work status.

ESR study of the liposome membrane physical parameters in the heating-cooling cycles

Changes of dynamic and structural parameters of egg yolk lecithin (EYL) liposome membranes in the heating-cooling cycles have been studied using the ESR spin probe method. The investigations were conducted in the range of temperatures from -18 degrees C to +60 degrees C. It has been found that in the range of temperatures -15 degrees C to +45 degrees C in both the heating and the cooling run the spectroscopic parameters changed practically along the same curve (reversible changes). However, after exceeding this range of temperatures one of the parameters (partition coefficient of the spin probe 2,2,6,6--tetramethylpiperidine -1-oxyl; TEMPO) changed along a closed curve, showing the phenomenon of thermal hysteresis. In the heating process the TEMPO content in liposome membranes was smaller than this in the cooling process. We assume that during the heating, the lipid molecules of the outer liposome layers dissolve in the aqueous medium. In the cooling process they can aggregate and form new liposomes, what in turn increases the surface of liposome membranes, accessible for the TEMPO probe (active surface).

Bimodal effect of amphiphilic biocide concentrations on fluidity of lipid membranes

Using the spin label method (ESR) it has been shown that biologically active, amphiphilic compounds (quaternary ammonium salts (AS) containing polar heads with single and double positive charge caused, at low concentrations, decrease fluidity of liposome membranes formed with egg yolk lecithin (EYL). At higher concentrations an increase in fluidity was observed. With compounds having a single positive charge minimum fluidity of membrane structure occurs in the range of 1 to 3%, with compounds containing double positive charge-in the range of 4-6%. That effect does not depend on polar head size and length of alkyl chains of the AS used. Analysis of the electrostatic interaction between positive charges and dipole system suggest that at low ion concentrations the binding energy of the system increases, while it decreases at high concentrations. For the model presented, maximum of binding energy of the system occurs at 3% of positive monovalent ions and at 6% of positive divalent ions admixed.

A new addition to face lift surgery: the argon gas surgical unit

In the quest to improve the technique of performing face lift surgery, we have encountered a device, the argon gas surgical unit, that offers a number of advantages over current techniques. These advantages include significant reductions in the amount of both intraoperative and postoperative blood loss, depth of tissue damage, amount of postoperative swelling, and amount of postoperative pain. This paper describes our experience with the use of the argon gas surgical unit compared with conventional electrocautery in 30 patients undergoing face lift. On histologic examination of the skin specimens, there was a consistent decrease in the depth of tissue damage with the argon gas surgical unit. With regard to blood loss, as a whole there was a marked decrease in the argon gas surgical unit group. Additionally, there is a clinically significant decrease in postoperative swelling in the patients in whom the argon gas surgical unit was employed that contributes to improved wound healing and an overall improved postoperative course.

Stretching and tissue expansion for rhytidectomy: an improved approach

Intraoperative expansion of the skin of the face supplies additional tissue that permits closure of the face lift incision with minimal tension. This paper presents the findings in rhytidectomy patients over the last 3 years using both intraoperative stretching and intraoperative stretching combined with tissue expansion utilizing the Man face lift expander. Sixty-seven patients underwent rhytidectomy surgery, of whom 50 were treated with stretching techniques alone and 17 were treated with the combined stretching and expansion method. The patients' ages ranged from 28 to 78 years. Results indicate that the patients treated with combined stretching and expansion had significantly more skin removed. This new technique appears to offer significant clinical advantages over usual face lifts.

Neutral and acidic species of human intestinal mucin. Evidence for different core peptides

Highly purified human mucins from postmortem intestinal tissue were fractionated on anion exchange columns to generate separate neutral and acidic species. The neutral mucin (less than 1.0 mol % sialic acid) was the major species (greater than 80% by weight) and contained a higher molar proportion of fucose, galactose, and N-acetylglucosamine, and a lower proportion of sialic acid and N-acetylgalactosamine than the acidic species (greater than 10 mol % sialic acid). Amino acid analyses revealed a highly significant enrichment in serine, aspartate, and alanine in the neutral species and proline, threonine, and glycine in the acidic species. Thiol reduction of each species to remove their integral 118,000-dalton component did not alter the essential interspecies differences. Differences in threonine, proline, and serine also remained after removal of all "naked" or pronase-susceptible peptide regions from each species. These results indicate that neutral and acidic mucins contain glycopeptide segments exclusive of their 118,000-dalton and naked peptide components, which differ in amino acid composition. The key amino acid markers are similar to those observed for fuco- and sialoglycopeptides obtained after proteolytic digestion of human colonic mucin by Gold et al. (Gold, D.V., Schochat, D., and Miller, F. (1981) J. Biol. Chem. 256, 6354-6358). The oligosaccharide composition of small intestinal and colonic mucin may therefore depend upon transcriptional control of the synthesis of specific mucin peptides as well as the post-translational activity of glycosyltransferases. These findings may have significance for the quality and functions of mucus produced in a variety of pathological states.

Drug allergy: incidence in terms of age and some drug allergens

The authors studied the incidence of drug allergy in 3 groups of subjects. In the first group the incidence was established in terms of the subjects' age: 1.8% in children up to 14 years old (323 subjects), 5.8% in middle-aged subjects (389 subjects) and 2.9% in the elderly (243 subjects). In the second partly selected group, drug allergy was studied in patients admitted to the 3rd Medical Clinic--Craiova between 2 Jan. 1981 and 31 Dec. 1982; 103 of the 8,760 patients admitted presented allergic reactions, a relatively high incidence rate (1.01%) as compared to other published reports. The third group of previously selected cases consisted of 197 patients who had come to the allergology service with complaints of present or past sensitivity to drugs. The total number of patients was 336 selected or preselected from about 10,000 subjects, to which 17 patients with a diagnosis of "asthmatic triad" must be added. Drug allergy in terms of the drug used was dominated by penicillin, pyramidon-algocalmin, aspirin, iodine preparations, etc.; foremost among the clinical syndrome were the dermatologic syndromes types I, III and IV; syndromes of the "anaphylactic shock" type, "serum sickeness" bronchial asthma, angioneurotic oedema.

The biceps femoris myocutaneous advancement flap: a useful modification for ischial pressure ulcer reconstruction

We describe a modification of the biceps femoris myocutaneous flap for reconstruction of ischial pressure ulcer defects. In this modification, all neural and vascular pedicles are preserved and the flap is advanced into the ischial defect rather than transposed as described in the literature. With this method, no transferred tissue is lost. Besides ensuring good tissue survival, the flap preserves a maximum number of reconstructive options in the event of ischial pressure ulcer recurrence. These advantages make the biceps femoris myocutaneous advancement flap our first choice for reconstruction of ischial pressure ulcer defects.

Desmoplastic malignant melanoma: a case report

A further case of desmoplastic malignant melanoma of the cheek is presented, bringing the total number of reported cases to 15. Its clinicopathological features and treatment are discussed.

The microarterial anatomy of the dorsalis pedis flap and its clinical applications

This study was undertaken to clarify the microanatomic details of the cutaneous branches of the dorsalis pedis artery. The microarterial anatomy of the dorsalis pedis flap area and its clinical implications are described.

Immunological, structural and functional relationships between an anti-complementary protein from Crotalus atrox venom, cobra venom factor and human C3

An anti-complementary protein which cross-reacts with antiserum to cobra venom factor (CoF) has been highly purified from Crotalus atrox venom (CAV). On an equal weight basis, the C. atrox factor (CA-F) had one-third the anti-complementary activity of CoF and similarly consumed the terminal components of complement via the alternative pathway. The subunit compositions of CoF and CAV were similar, each being composed of alpha and beta chains held together by covalent and non-covalent bonds. Agarose gel diffusion analysis using monospecific antiserum to CoF detected a reaction of partial immunological identity between CoF and CA-F and between C3 and CA-F with the CoF and C3 precipitin lines spurring over the CA-F lines. Thus CA-F probably represents a C. atrox C3 protein which is capable of activating the alternative complement pathway via the amplification loop in a manner analogous to that of C3b and CoF.

Kinetic studies on the fragmentation of the third component of complement (C3) by trypsin

The kinetics of cleavage of C3 by trypsin was analyzed by electrophoresis in agarose and in polyacrylamide gels containing sodium dodecyl sulfate and the data obtained were used to construct an anatomical model for C3 showing the sites of tryptic attack, the fragments generated, and their composition. Trypsin was shown to cleave C3 in a stepwise fashion. The attack was initially directed at the alpha-polypeptide chain and resulted in the generation of C3a and C3b. Further cleavage of the alpha-chain of C3b, converted it into C3b1 and then into C3d and C3c. Cleavage of the beta-chain by trypsin occurred only at the C3c stage with the release of a small peptide (m.w. 12,000) from C3c and the formation of C3c'. On immunoelectrophoresis, C3c' had a less anodal mobility compared to the beta1A mobility of C3c. C3a, once formed could be further cleaved to give residual fragments with decreasing net positive charge. Exposure of C3 to acid conditions, pH 5.0 or below, rendered the molecule exceedingly susceptible to tryptic degradation.