Association between soluble lectin-like oxidized low-density lipoprotein receptor 1 levels and coronary slow flow phenomenon

Introduction

The coronary slow flow phenomenon (CSFP) has been associated with myocardial ischemia, myocardial infarction, life-threatening arrhythmias, sudden cardiac death and increased cardiovascular mortality similar to coronary artery disease (CAD). Possible underlying mechanisms of CSFP are endothelial dysfunction, chronic inflammation, microvascular dysfunction and diffuse atherosclerosis. Soluble lectin-like oxidized low-density lipoprotein receptor-1 (sLOX-1) seems to play an important role in the pathogenesis of atherosclerosis. We hypothesized that sLOX-1 might be associated with CSFP, and aimed to research the relationship between sLOX-1 and CSFP.

Material and methods

Forty patients with angiographically proven CSFP and 43 patients with a normal coronary flow pattern (NCFP) were included in this study. Coronary blood flow was measured according to the Thrombolysis In Myocardial Infarction (TIMI) frame count method. sLOX-1 levels were measured in all study subjects.

Results

Serum levels of sLOX-1 were significantly higher in the CSFP group than the NCFP group (1061.80 ±422.20 ng/ml vs. 500.043 ±282.97 ng/ml, p < 0.001, respectively). Multivariate logistic regression analysis including sLOX-1, MPV, GGT and uric acid levels revealed a significant association between sLOX-1 levels and CSFP (Exp (B)/OR: 1.006, 95% CI: 1.002–1.010, p = 0.001).

Conclusions

The present study demonstrated that serum sLOX-1 levels were significantly higher in patients with CSFP and there was a strong association between high sLOX-1 levels and CSFP. High serum sLOX-1 levels may have an important role in the pathogenesis of CSFP. Future studies are needed to confirm these results.     

EFFECT OF ATHLETIC TAPING AND KINESIOTAPING? ON MEASUREMENTS OF FUNCTIONAL PERFORMANCE IN BASKETBALL PLAYERS WITH CHRONIC INVERSION ANKLE SPRAINS

Background:

Chronic inversion ankle sprains are common in basketball players. The effect of taping on functional performance is disputed in the literature. Kinesiotaping® (KT®) is a new method that is being used as both a therapeutic and performance enhancement tool. To date, it appears that no study has investigated the effect of ankle KT® on functional performance.

Purpose:

To investigate the effects of different types of taping (KT® using Kinesio Tex®, athletic taping) on functional performance in athletes with chronic inversion sprains of the ankle.

Study Design:

Crossover Study Design

Methods:

Fifteen male basketball players with chronic inversion ankle sprains between the ages of 18 and 22 participated in this study. Functional performance tests (Hopping test by Amanda et al, Single Limb Hurdle Test, Standing Heel Rise test, Vertical Jump Test, The Star Excursion Balance Test [SEBT] and Kinesthetic Ability Trainer [KAT] Test) were used to quantify agility, endurance, balance, and coordination. These tests were conducted four times at one week intervals using varied conditions: placebo tape, without tape, standard athletic tape, and KT®. One-way ANOVA tests were used to examine difference in measurements between conditions. Bonferroni correction was applied to correct for repeated testing.

Results:

There were no significant differences among the results obtained using the four conditions for SEBT (anterior p=0.0699; anteromedial p=0.126; medial p=0.550; posteromedial p=0.587; posterior p=0.754; posterolateral p=0.907; lateral p=0.124; anterolateral p=0.963) and the KAT dynamic measurement (p=0.388). Faster performance times were measured with KT® and athletic tape in single limb hurdle test when compared to placebo and non-taped conditions (Athletic taping- placebo taping: p=0.03; athletic taping- non tape p=0.016;KT®- Placebo taping p=0.042; KT®-Non tape p=0.016). In standing heel rise test and vertical jump test, athletic taping led to decreased performance. (Standing heel rise test: Athletic taping- placebo taping p=0.035; athletic taping- non tape p=0.043; athletic tape- KT® p<0.001) (Vertical jump test: Athletic taping- placebo taping p=0.002: athletic taping- non tape p=0.002; KT®- athletic tape p<0.001)

Conclusion:

Kinesiotaping® had no negative effects on a battery of functional performance tests and improvements were seen in some functional performance tests.

Clinical Relevance:

Ankle taping using Kinesio Tex® Tape did not inhibit functional performance.     

DNA-encoded chemistry technology yields expedient access to SARS-CoV-2 Mpro inhibitors

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has killed more than 4 million humans globally, but there is no bona fide Food and Drug Administration–approved drug-like molecule to impede the COVID-19 pandemic. The sluggish pace of traditional therapeutic discovery is poorly suited to producing targeted treatments against rapidly evolving viruses. Here, we used an affinity-based screen of 4 billion DNA-encoded molecules en masse to identify a potent class of virus-specific inhibitors of the SARS-CoV-2 main protease (M^pro) without extensive and time-consuming medicinal chemistry. CDD-1714, the initial three-building-block screening hit (molecular weight [MW] = 542.5 g/mol), was a potent inhibitor (inhibition constant [K_i] = 20 nM). CDD-1713, a smaller two-building-block analog (MW = 353.3 g/mol) of CDD-1714, is a reversible covalent inhibitor of M^pro (K_i = 45 nM) that binds in the protease pocket, has specificity over human proteases, and shows in vitro efficacy in a SARS-CoV-2 infectivity model. Subsequently, key regions of CDD-1713 that were necessary for inhibitory activity were identified and a potent (K_i = 37 nM), smaller (MW = 323.4 g/mol), and metabolically more stable analog (CDD-1976) was generated. Thus, screening of DNA-encoded chemical libraries can accelerate the discovery of efficacious drug-like inhibitors of emerging viral disease targets.

On March 11, 2020, the World Health Organization recognized the COVID-19 outbreak caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as a pandemic. Although vaccines are being approved for emergency use to fight COVID-19 (https://www.cdc.gov/vaccines/covid-19/index.html), there is an urgent need for effective new drug treatments to reduce the morbidity and mortality for patients who have already contracted COVID-19, not yet received the vaccine, are infected with SARS-CoV-2 variants that are more resistant to the vaccines, and for future coronavirus pandemics. The conventional process of drug discovery is based on automated high-throughput screening (HTS) or structure-based drug design. HTS requires a complex infrastructure, the development a miniaturized assay tailored to the individual target, and generally the need for extensive medicinal chemistry to optimize modestly potent hits that arise from the screen. The development of such screening methods is therefore sluggish and not well-suited to meet the present public health demands imposed by the COVID-19 pandemic. As an HTS alternative, structure-based approaches are advantageous when available since the rational synthesis of analogs can accelerate the generation of potent compounds. Prior to our work, other investigations have relied on structure-based methods and computational approaches to optimize moderately potent M^pro inhibitors (1, 2). However, the need for a high-resolution X-ray structure to initiate a drug discovery campaign can be extremely rate-limiting, if not altogether prohibitive. Finally, drug repurposing is often utilized as an efficient discovery strategy since it can bypass issues related to safety; however, the application of a compound to a target for which it was not optimized may never achieve maximal therapeutic benefit. A screening process which circumvents these challenges would significantly accelerate the pace for identification of clinical candidate compounds. DNA-encoded chemistry technology (DEC-Tec) is an increasingly attractive strategy to explore chemical space to identify small molecules and high-affinity binders for a multitude of protein targets (3–7). DEC-Tec involves the creation of libraries of drug-like molecules covalently attached to a unique DNA barcode that enables identification of binders for a target in a pool of millions to billions of compounds. DEC-Tec addresses these pitfalls related to HTS by screening of billions of DNA-tagged small molecules as a single mixture using an affinity selection assay (4, 8–13). This expanded number of drug-like small molecules allows for the identification of high-affinity ligands using a technologically practical format. For example, the modest protein requirement and low price of DNA sequencing both contribute to the inexpensive cost of screening small-molecule DNA-encoded chemical libraries. Additionally, the various steps involved in the selection process, which include the affinity selection to the protein, DNA sample preparation, sequencing, and data analysis, can each be performed in several days, providing for a highly expeditious screening process. Finally, the large number of compounds employed in DEC-Tec is leveraged to provide binders in the absence of preexisting structural information related to the target or its ligand-binding preferences. We believe that these features of DEC-Tec provided clear advantages for discovering novel small-molecule agents against SARS-CoV-2 targets.With our collection of over 55 DEC-Tec libraries (4 billion unique molecules) including protease-biased libraries (6) and various libraries utilizing DNA-compatible reactions developed in-house (14–22), the Center for Drug Discovery at Baylor College of Medicine has the operational capacity to support emergent action at the onset of pandemics. The genome of SARS-CoV-2 comprises six major open reading frames including two polyproteins that undergo extensive proteolytic processing to create functional proteins that perform tasks essential for viral propagation (23). This processing is largely achieved by SARS-CoV-2 main protease (M^pro or 3CL^pro) (24), a cysteine protease enzyme indispensable for the virus lifecycle and a key therapeutic target. Our hypothesis is that SARS-CoV-2 M^pro screening of billions of DNA-encoded molecules, generation of small-molecule-M^pro cocrystals, and minimal medicinal chemistry follow-up would generate drug-like inhibitors of M^pro for emergent use in patients infected with SARS-CoV-2, related variants, and related coronaviruses.To screen our DEC-Tec collection, we first constructed the pSUMO-SARS-CoV-2-M^pro plasmid carrying the SUMO-M^pro-His6 tag (SI Appendix, Fig. S1). The M^pro open reading frame sequence was flanked on the N terminus by its endogenous cleavage site (SAVLQ↓SGFRK) and on its C terminus by a PreScission cleavage site (SGVTFQ↓GP). The SUMO-M^pro-His6 recombinant fusion protein was expressed from Escherichia coli BL21(DE3), and the M^pro enzyme with its authentic N terminus and the His6 tag was purified as described in Methods and SI Appendix, Fig. S2. Because our nickel magnetic screen capture test requires a His tag, the M^pro-His6 protein was used for DEC-Tec library screening. For crystallography and enzymatic assays, the M^pro-His6 protein was treated with PreScission enzyme to remove the C-terminal 6-His tag, and the M^pro was further purified by gel filtration chromatography. Using a fluorescent peptide, Dabcyl-KTSAVLQSGFRKM-E(Edans)-NH₂, as a reporter substrate, we first confirmed that the purified recombinant M^pro-His6 and the M^pro (“native”) lacking the His6 tag were very active and demonstrated nearly identical bioactivity in vitro.Forty unique DNA-encoded chemical libraries (DECLs) cumulatively containing 3.987 billion drug-like compounds were pooled together for the screen of M^pro-His6 binding compounds. Each library was prequantitated by qPCR, and library pooling was conducted to have 1 million copies of each compound present in the pool. Our selection for M^pro-His6 binders comprised a three-round affinity selection with an M^pro-His6 protein concentration of 1 µM. An independent affinity selection was performed in parallel without protein to serve as a no-target control to identify any nonprotein specific enrichment. Our Illumina next-generation sequencing identified a chemical series consistently enriched with excellent structure–enrichment relationships (SER) from qDOS28_1, one of our DEC-Tec libraries (Fig. 1 and SI Appendix, Scheme S1). The process of modern HTS screening has the capability to interrogate the activity of ∼100,000 small molecules per day in a specialized well-based assay (25, 26). Here, DEC-Tec was used to evaluate 4 billion small molecules as a single mixture in 1 d against M^pro. Thus DEC-Tec, through its breakneck rate of screening, offers a tremendous advantage to infectious disease targets of pathogens that pose both present and imminent public health threats.Open in a separate windowFig. 1.Enrichment profile of qDOS28_1 against SARS-CoV-2 M^pro at 1 μM. The selection data have shown the enrichment of the same BB2 (in red) and BB3 (in black) with various BB1 (in blue), where the BB1 features di-substituted amine. The methyl amide (in black) represents the DNA attachment point. The number of counts in the box represents the number of observed library members.The DNA sequences resulting from the M^pro selection were analyzed (27) to determine structural features that were enriched to prioritize compounds to be synthesized without the DNA barcode (off DNA). Compounds within DECLs are generally constructed from the union of three building blocks (trisynthons). Compounds enriched from the selection can be analyzed for those sharing one or two building blocks (monosynthons vs. disynthons) in common, leading to the identification of critical structure–enrichment relationships. The consideration of these SER leads to potent compounds in an efficient manner, supplanting the need for many rounds of laborious medicinal chemistry. Based on the M^pro selection analysis, the trisynthon CDD-1714 (“hit” molecule) and its smaller disynthons CDD-1712 and CDD-1713 (Fig. 2) were synthesized off DNA in two to four steps from commercially available materials (SI Appendix). To characterize the potency of selected compounds toward M^pro, we utilized the above described fluorescent peptide reporter assay. For initial compound screening, 25 µM of compound was incubated with M^pro and only compounds which inhibited M^pro proteolytic activity >90% were considered as candidates. The inhibition constant (K_i) values of these compounds were determined with concentrations ranging from 4 nM to 4,000 nM (SI Appendix, Fig. S3 and Table S1). Since M^pro-His6 was used in library screening, we performed parallel enzyme inhibition assays using either M^pro-His6 or M^pro to evaluate the potency of compounds toward M^pro proteolytic activity in the presence and absence of His tag. Using this protease inhibition assay, we found that CDD-1713 and CDD-1714 inhibited M^pro with K_i values of 45 nM and 20 nM, respectively (Fig. 2 and SI Appendix, Fig. S3). These results indicated that building block 1 (BB1), closest to the DNA attachment site, was less critical for binding and inhibition; CDD-1713 was chosen for optimization efforts based on its low molecular weight (353.3 g/mol) and good cLogP (2.01). CDD-1713 contains a reactive aldehyde functional group capable of forging covalent bonds with proteins, and thus we initially turned our attention toward examining the importance of the aldehyde moiety. Deleting the aldehyde (CDD-1793) or replacing with hydroxymethyl (CDD-1776) completely abolished the activity, while replacing the aldehyde with hydroxymethyl ketone (CDD-1886) drastically decreased M^pro inhibition by greater than 100-fold (Fig. 2). We therefore concluded that the aldehyde was required for activity and next proceeded to further probe its electrophilic nature. Generation of the more electron-deficient des-methoxy analog (CDD-1976) showed better inhibition compared to CDD-1713. Aldehydes have the propensity to react nonselectively; however, CDD-1712 did not show any activity, and additionally we synthesized CDD-1847 which incorporates an N-methylindazole and found that it completely lost activity. Given this remote substitution to the aldehyde, it is likely that the M^pro inhibitory activity of CDD-1713 and related analogs results from a specific binding interaction with M^pro. While aldehydes may pose a liability in drugs, compounds that contain aldehydes have been evaluated in humans, demonstrating good selectivity and other drug-like properties (28–33). To confirm that the potent inhibitors bound tightly to M^pro, we performed a protein thermal shift stability assay (thermofluor assay). CDD-1713, CDD-1714, and CDD-1976 cause a concentration-dependent stabilization of M^pro, with CDD-1976 showing the most pronounced temperature shift at all three protein concentrations (SI Appendix, Fig. S4). Taken altogether, the DEC-Tec process involving affinity selection of 4 billion DNA-encoded compounds against M^pro, analysis of SER, and synthesis of the exemplary compounds (including with different electrophiles) off DNA (SI Appendix, Fig. S5 and Table S1) yielded potent and selective inhibitors of M^pro. We note that CDD-1713, which was inferred directly from the selection, was synthesized and validated in rapid fashion (less than 10 wk from start to finish; SI Appendix, Table S2), highlighting DEC-Tec’s ability to produce potent compounds without extensive synthetic optimization.Open in a separate windowFig. 2.SARS-CoV-2 M^pro hits, analogs and examples of enzymatic inhibitory activity of these key molecules. (A) Small molecules synthesized off DNA are shown. Numbers indicate K_i values determined as described in Methods. Inactive = compounds that inhibited M^pro activity by less than 90% with 25 µM compound were considered inactive. (B) Inhibition K_i value determination against M^pro-His6. Concentration-dependent inhibition curve of CDD-1714, CDD-1713, and CDD-1976.Using the M^pro sequence, BLAST search analysis of the reference proteins encoded by the human genome shows no significant similarity. To confirm that our M^pro inhibitors do not show any potential off-target inhibition of major proteases in humans, we tested their effects on four important proteases representing four classes of human protease enzymes. As might be expected from our BLAST search, none of our inhibitors block the enzymatic activity of cathepsin B (a cysteine protease like M^pro), thrombin (a serine protease), renin (an aspartic protease), or matrix metallopeptidase-1 (MMP-1; SI Appendix, Fig. S6). Thus, our potent molecules are anticipated to have specific effects on inhibition of viral protein processing in vivo without altering human cellular activity.To understand the interactions of CDD-1713 with M^pro we determined the X-ray crystal structure of the enzyme in complex with the inhibitor. For this purpose, the purified enzyme was cocrystallized with CDD-1713. The structure was determined in space group C121 at 1.8-Å resolution with a single monomer in the asymmetric unit (Fig. 3 and SI Appendix, Table S3). The biological dimer is formed by the monomer and its symmetry-related monomer across the crystallographic two-fold axis, as seen previously in M^pro structures (1, 34).Open in a separate windowFig. 3.Crystal structure of M^pro in complex with CDD-1713. (A) Structure of M^pro (tan) with CDD-1713 (cyan). The F_o – F_c density map is shown for the inhibitor with contouring level at 3σ. The catalytic site is located within the square. (B) Magnified view of the catalytic center. Carbon atoms of the inhibitor are cyan, nitrogen atoms are blue, and oxygen atoms are red. The M^pro amino acid residues involved in CDD-1713 binding are shown as stick models and labeled. M^pro residues that form hydrogen bonds (dashed black lines) and van der Waals interactions with CDD-1713 are colored in orange and green, respectively. One water molecule involved in hydrogen bond was colored red. The site chain of Asn142 is not shown to avoid obstruction of the view of hydrogen bonds on the aldehyde group. (C) F_o − F_c omit maps showing electron density of the covalent bond formed between Cys145 and CDD-1713 contoured at 3s. Continuous electron density is present between C¹³ on the aldehyde group of CDD-1713 and thiol on the side chain of Cys145. (D) Two-dimensional diagram of the M^pro interaction with CDD-1713 generated by Ligplot⁺. Carbon atoms are shown in black, nitrogen atoms are blue, and oxygen atoms are red. Ligands are colored cyan and hydrogen bonds are represented as black dashed lines, hydrogen bond contacts are colored orange, and hydrophobic contacts are represented as green spoke arcs. Water molecule was presented as red sphere. The length of each hydrogen bond is labeled.Examination of the structure reveals CDD-1713 is positioned in the active site of M^pro with the electron density clearly showing a 1.7-Å covalent bond from the aldehyde of CDD-1713 to Sγ of the catalytic residue Cys145 (Fig. 3 B and C). The carbonyl oxygen of the aldehyde forms hydrogen bonds with the main chain nitrogens of Gly143 and Cys145 that form the oxyanion hole of the enzyme. Similar interactions have been reported for bicyclopropane-containing inhibitors of M^pro with an aldehyde warhead (1). The active site of M^pro contains four subsites (S1′, S1, S2, and S3) that accommodate the amino acids of the peptide substrate or peptidomimetic inhibitors (P1′, P1, P2, and P3) (35, 36). M^pro has a stringent requirement for a P1 glutamine occupying the S1 subsite (35). The indazole ring of CDD-1713 inserts into the S1 pocket (Fig. 3). The NH of the indazole group forms hydrogen bonds with the side-chain Oε of Glu166 and the main-chain O of Phe140, while the N of the indazole forms a hydrogen bond with the Nε2 of His163 (Fig. 3). In addition, the indazole group makes hydrophobic interactions with Phe140, Leu141, Asn142, and Glu166 (Fig. 3). The extensive interactions of the indazole with residues in the S1 pocket is of note in that the residues in the S1 pocket are largely conserved among coronavirus M^pro enzymes, suggesting CDD-1713 may exhibit broad M^pro specificity (37). The central phenyl ring of CDD-1713 makes hydrophobic interactions with Asn142 and positions the aldehyde group for interaction with Cys143. The O-alkyl chain on the central phenyl ring occupies a region between the S2 and S1′ subsites. The terminal methyl groups of the dimethylamide make hydrophobic interactions with His41, Cys44, Thr45, Ser46, and Met49 (Fig. 3D). Note that the dimethylamide is partially buried in the structure, suggesting the BB1 group in CDD-1714 and the DNA-attachment site may sterically clash with the Thr45-Met49 region. However, the rotatable bonds in the O-alkyl chain may allow positioning consistent with binding of the BB1 group and solvent exposure of the DNA-attachment point (Fig. 3B). Further, the methoxy group attached to the central phenyl ring is solvent-exposed and does not interact with M^pro. The design of M^pro inhibitors has mostly centered on templates having multiple amide bonds to mimic the enzyme’s natural peptide substrates (1, 34, 38–41). CDD-1713 differs significantly from the amide-based inhibitors, allowing it to forge different interactions within the same M^pro active site (SI Appendix, Fig. S3E). Thus, the DEC-Tec approach supports the elucidation of novel pharmacophores to enzymes without specific design principles or prior knowledge of substrate preferences.Using mouse and human liver microsomes, CDD-1713 was found to be metabolically labile in both mouse and human assays, while CDD-1976 is more stable in human liver microsomes, but not mouse (SI Appendix, Table S4). CDD-1713 and CDD-1976 displayed moderate cell permeability in an uptake assay of HepG2 cells (SI Appendix, Fig. S7A) and no obvious cytotoxicity in HepG2 cells was observed for both compounds at 100 μM (SI Appendix, Fig. S7B). Both CDD-1713 and CDD-1976 are relatively stable in human and mouse plasma; 80% of compounds remained in plasma after 2-h incubation (SI Appendix, Fig. S7C).The viral inhibitory capacity of compounds CDD-1713 and CDD-1976 was demonstrated using a real-time cell analysis (RTCA) assay. To evaluate viral inhibition, different concentrations of the M^pro inhibitors were added to VERO E6 cells incubated with a live strain of the SARS-CoV-2 virus. Subsequently, the growth kinetics of the cells were followed over 75 h. In the positive control group, SARS-CoV-2 effectively caused cell death, which was observed as a decrease in the normalized cell index compared to the negative control group (no virus). CDD-1713 and CDD-1976 successfully reduced cell death in a dose-dependent manner, indicating that virus replication was stopped (Fig. 4). CDD-1976 was found to be most effective, with a calculated half-maximal inhibitory concentration (IC₅₀) of 2.50 µM, followed by CDD-1713 with an IC₅₀ of 5.19 µM. CDD-1847, a closely related analog that abolishes binding to M^pro, was unable to prevent cell death by the SARS-CoV-2 virus.Open in a separate windowFig. 4.Normalized cell index plotted versus concentration (log) of M^pro drug compounds measured using the xCELLigence RTCA. Average data points from duplicate measurements. A sigmoidal dose–response curve was fitted to determine IC₅₀ values for each M^pro drug compound (lines).In summary, using a DEC-Tec–based strategy we identified CDD-1713 and CDD-1976 as a class of potent and selective inhibitors of SARS-CoV-2 M^pro that block viral reproduction in a short span of time. X-ray crystallography was further deployed to elucidate the structural details of M^pro inhibition by CDD-1713, and this information should enable further development of drug-like M^pro inhibitors. These studies support DEC-Tec as an expedient and effective paradigm for generating therapeutics against critical targets within the SARS-CoV-2 genome.     

Effects of N-acetylcysteine on myocardial ischemia–reperfusion injury in bypass surgery

Myocardial ischemia–reperfusion injury may complicate coronary artery bypass grafting (CABG) operations. N-Acertylcysteine (NAC) had antioxidant and microcirculatory effects, and inhibits neutrophil aggregation. The aim of this study was to determine the effects of NAC in limiting myocardial ischemia–reperfusion injury in CABG operations. Twenty patients undergoing elective coronary bypass operation with cardiopulmonary bypass were enrolled and randomly assigned to two groups: a control group operated with a routine CABG protocol, and one where NAC was administered intravenously during the operation (NAC group). Blood samples from coronary sinus for tumor necrosis factor-α assay, myocardial biopsy specimens for chemiluminescent luminol, and lucigenin measurements of reactive oxygen species were taken. The luminol (specific for ^•OH, H₂O₂, and HOCl⁻ radicals) and lucigenin (specific for O₂^•−) levels and the difference ratios after reperfusion were significantly lower in the NAC group. Tumor necrosis factor-α levels increased in the control group but, in contrast, a significant decrease was detected in the NAC group (P < 0.01). Creatine kinase-MB levels at 6 and 12 hours were singnificantly lower in the NAC group (P = 0.02). N-Acetylcysteine has potential effects to limit ischemia reperfusion injury during CABG operations. We believe that its effects on clinical outcome may be more apparent in patients prone to ischemia–reperfusion injury.     

A right sliding indirect inguinal hernia containing paraovarian cyst,fallopian tube,and ovary: a case report

Albeit very uncommon, the hernia sac may contain unusual structures such as vermiform appendix, acute appendicitis, ovary, fallopian tube and, urinary bladder. Most of the cases of hernia containing ovary and fallopian tubes were reported to be found in children and, often accompanied with other congenital anomalies of genital tract. We present the first case of sliding inguinal hernia containing right ovary and fallopian tube and a right paraovarian cyst in 80-year-old, multiparous patient without any associated genital anomaly. The hernia was repaired with plication darn, while the paraovarian cyst was excised and adnexa were preserved. It is of utmost importance to keep in mind that the hernia sac may contain almost any abdominal organ, and surgical dissection should be carried out accordingly. Pathophysiologically, the ovary might be simply pulled along with a sliding paraovarian cyst or the paraovarian cyst might be accompanying the maldescended ovary. There seems to be a need for clinical and experimental studies to further explain the mechanisms that apply to the pathogenesis of sliding inguinal hernias.     

Can pentoxifylline improve the sperm motion and ICSI success in the primary ciliary dyskinesia?

Primary ciliary dyskinesia (PCD), previously known as immotile cilia syndrome, can cause respiratory and reproductive problems. Because of the impaired motion of microtubules the patients suffer upper respiratory tract problems. Infertility is an other issue of these patients. Several attempt have been proposed to bring back sperm motion and to improve intracytoplasmic sperm injection (ICSI) results. With our case we have described the management of a male infertility that causes from immotile cilia. The role of ICSI with incubated and activated ejaculatory sperm by pentoxifylline in the patient of PCD or as commonly named immotile cilia syndrome.     

Deformation and Fracture of Mtwo Rotary Nickel-Titanium Instruments After Clinical Use

IntroductionIn recent years, a number of rotary nickel titanium (NiTi) systems have been developed to provide better, faster, and easier cleaning and shaping of the root canal system. Although the NiTi instruments are more flexible than the stainless steel files, the main problem with the rotary NiTi instruments is the failure of the instruments. The aim of this study was to evaluate the deformation and fracture rate of Mtwo rotary nickel-titanium instruments (VDW, Munich, Germany) discarded after routine clinical use.MethodsA total of 593 Mtwo rotary NiTi instruments were collected after clinical use from the clinic of endodontics over 12 months. The length of the files was measured using a digital caliper to determine any fracture, and then all the files were evaluated under a stereomicroscope for defects such as unwinding, curving, or bending and fracture. The fracture faces of separated files were also evaluated under a scanning electron microscope. The data were analyzed using a chi-square and z test.ResultsA percentage of all files (25.80%) showed defects, and the major defect was fracture (16.02%). The most frequently fractured file was #10.04 (30.39%). Deformations without fracture were mostly observed on #15.05 files (25.47%).ConclusionsA higher rate of deformation was observed for #10.04 and #15.05 files. Therefore, these files should be considered as single-use instruments. Because cyclic fatigue was the cause of 71.58% of the instrument fractures, it is also important not to exceed the maximum number of usage recommended by the manufacturer and discard the instruments on a regular basis.