Salvaging donated kidneys from prolonged warm ischemia during ex vivo hypothermic oxygenated perfusion.

Prolonged warm ischemic is the main cause discarding donated organs after cardiac death. Here, we identified that prolonged warm ischemic time induced disseminated intravascular coagulation and severe capillary vasospasm after cardiac death of rat kidneys. Additionally, we found a significant accumulation of fibrinogen in a hypoxic cell culture of human umbilical vein epithelial cells and in isolated kidneys exposed to prolonged warm ischemic following flushing out of blood. However, pre-flushing the kidney with snake venom plasmin in a 90-minute warm ischemic model maximized removal of micro thrombi and facilitated the delivery of oxygen and therapeutic agents. Application of carbon monoxide-releasing CORM-401 during ex vivo hypothermic oxygenated perfusion achieved multipath protective effects in prolonged warm ischemic kidneys. This led to significant improvements in perfusion parameters, restoration of the microcirculation, amelioration of mitochondrial injury, oxidative stress, and apoptosis. This benefit resulted in significantly prolonged warm ischemic kidney recipient survival rates of 70%, compared with none in those receiving ex vivo hypothermic oxygenated perfusion alone. Significantly, ex vivo hypothermic oxygenated perfusion combined with cytoprotective carbon monoxide releasing CORM-401 treatment meaningfully protected the donated kidney after cardiac death from ischemia-reperfusion injury by reducing inflammation, oxidative stress, apoptosis, and pathological damage. Thus, our study suggests a new combination treatment strategy to potentially expand the donor pool by increasing use of organs after cardiac death and salvaging prolonged warm ischemic kidneys.

Aligned lovastatin-loaded electrospun nanofibers regulate collagen organization and reduce scar formation.

Excessive scar formation caused by cutaneous injury leads to pruritus, pain, contracture, dyskinesia, and unpleasant appearance. Functional wound dressings are designed to accelerate wound healing and reduce scar formation. In this study, we fabricated aligned or random polycaprolactone/silk fibroin electrospun nanofiber membranes with or without lovastatin loading, and then evaluated their scar-inhibitory effects on wounds under a specific tension direction. The nanofiber membranes exhibited good controlled-release performance, mechanical properties, hydrophilicity, and biocompatibility. Furthermore, nanofibers' perpendicular placement to the tension direction of the wound most effectively reduced scar formation (the scar area decreased by 66.9%) and promoted skin regeneration in vivo. The mechanism was associated with aligned nanofibers regulated collagen organization in the early stage of wound healing. Moreover, lovastatin-loaded nanofibers inhibited myofibroblast differentiation and migration. Both tension direction-perpendicular topographical cues and lovastatin synergistically inhibited mechanical transduction and fibrosis progression, further reducing scar formation. In summary, our study may provide an effective scar prevention strategy in which individualized dressings can be designed according to the local mechanical force direction of patients' wounds, and the addition of lovastatin can further inhibit scar formation. STATEMENT OF SIGNIFICANCE: In vivo, cells and collagen are always arranged parallel to the tension direction. However, the aligned topographic cues themselves promote myofibroblast differentiation and exacerbate scar formation. Electrospun nanofibers' perpendicular placement to the tension direction of the wound most effectively reduces scar formation and promotes skin regeneration in vivo. The mechanism is associated with tension direction-perpendicular nanofibers reregulate collagen organization in the early stage of wound healing. In addition, tension direction-perpendicular topographical cue and lovastatin could inhibit mechanical transduction and fibrosis progression synergistically, further reducing scar formation. This study proves that combining topographical cues of wound dressing and drugs would be a promising therapy for clinical scar management.

Chemoenzymatic Total Synthesis of Haemophilus ducreyi Lipooligosaccharide Core Octasaccharides Containing Natural and Unnatural Sialic Acids.

The first total synthesis of Haemophilus ducreyi lipooligosaccharide core octasaccharides containing natural and unnatural sialic acids has been achieved by an efficient chemoenzymatic approach. A highly convergent [3 + 3] coupling strategy was developed to chemically assemble a unique hexasaccharide bearing multiple rare higher-carbon sugars d-glycero-d-manno-heptose (d,d-Hep), l-glycero-d-manno-heptose (l,d-Hep), and 3-deoxy-α-d-manno-oct-2-ulosonic acid (Kdo). Key features include sequential one-pot glycosylations for oligosaccharide assembly and the construction of the challenging α-(1 → 5)-linked Hep-Kdo glycosidic bond by gold-catalyzed glycosylation with a glycosyl ortho-alkynylbenzoate donor. Furthermore, the sequential enzyme-catalyzed regio- and stereoselective introduction of a galactose residue using ß-1,4-galactosyltransferase and different sialic acids using a one-pot multienzyme sialylation system was efficiently accomplished to provide the target octasaccharides.

Convergent Synthesis and Anti-Pancreatic Cancer Cell Growth Activity of a Highly Branched Heptadecasaccharide from Carthamus tinctorius.

Bioactive polysaccharides from natural resources target various biological processes and are increasingly used as potential target molecules for drug development. However, the accessibility of branched and long complex polysaccharide active domains with well-defined structures remains a major challenge. Herein we describe an efficient first total synthesis of a highly branched heptadecasaccharide moiety of the native bioactive galectin-3-targeting polysaccharide from Carthamus tinctorius L. as well as shorter fragments of the heptadecasaccharide. The key feature of the approach is that a photo-assisted convergent [6+4+7] one-pot coupling strategy enables rapid assembly of the heptadecasaccharide, whereby a photoremovable o-nitrobenzyl protecting group is used to generate the corresponding acceptor for glycosylation in situ upon ultraviolet radiation. Biological activity tests suggest that the heptadecasaccharide can target galectin-3 and inhibit pancreatic cancer cell growth.

Chemiluminescence of 3-aminophthalic acid anion-hydrogen peroxide-cobalt (II).

The 3-aminophthalic acid anion is a light emitter in luminol chemiluminescence. In the present study, the chemiluminescence of the 3-aminophthalic acid anion itself in the presence of hydrogen peroxide-cobalt (II) was studied. The results indicated that 3-aminophthalic acid anion is highly chemiluminescent in the typical hydrogen peroxide-cobalt (II) system. The peak wavelength of this chemiluminescence and the kinetic profile of the 3-aminophthalic acid anion-hydrogen peroxide-cobalt (II) reaction showed similarity with that of luminol, but the chemiluminescence of 3-aminophthalic acid anion had a much lower background signal. In addition, the chemiluminescence mechanism of 3-aminophthalic acid anion-hydrogen peroxide-cobalt (II) was also discussed and speculated as the interaction between 3-aminophthalic acid anion and singlet oxygen.

Design, synthesis and structure-based optimization of novel isoxazole-containing benzamide derivatives as FtsZ modulators.

Antibiotic resistance among clinically significant bacterial pathogens is becoming a prevalent threat to public health, and new antibacterial agents with novel mechanisms of action hence are in an urgent need. Utilizing computational docking method and structure-based optimization strategy, we rationally designed and synthesized two series of isoxazol-3-yl- and isoxazol-5-yl-containing benzamide derivatives that targeted the bacterial cell division protein FtsZ. Evaluation of their activity against a panel of Gram-positive and -negative pathogens revealed that compounds B14 and B16 that possessed the isoxazol-5-yl group showed strong antibacterial activity against various testing strains, including methicillin-resistant Staphylococcus aureus and penicillin-resistant S. aureus. Further molecular biological studies and docking analyses proved that the compound functioned as an effective inhibitor to alter the dynamics of FtsZ self-polymerization via a stimulatory mechanism, which finally terminated the cell division and caused cell death. Taken together, these results could suggest a promising chemotype for development of new FtsZ-targeting bactericidal agent.

Synthesis and antibacterial activity of novel 3-O-arylalkylcarbamoyl-3-O-descladinosyl-9-O-(2-chlorobenzyl)oxime clarithromycin derivatives.

A novel series of 3-O-arylalkylcarbamoyl-3-O-descladinosyl-9-O-(2-chlorobenzyl)oxime clarithromycin derivatives, were designed, synthesized and evaluated for their in vitro antibacterial activity. These derivatives were found to have strong activity against susceptible and resistant bacteria strains. Among them, compounds 7a and 7q showed the most potent activity (0.125 µg/mL) against erythromycin-resistant S. pneumoniae expressing the mefA gene. Moreover, compounds 7f, 7i, 7p and 7z displayed remarkably improved activity (4 µg/mL) against penicillin-resistant S. aureus ATCC31007, and compounds 7a, 7b, 7f, 7p and 7z showed improved activity (8 µg/mL) against erythromycin-resistant S. pyogenes. In particular, compound 7z exhibited potent and balanced activity against the tested drug-susceptible and -resistant bacterial strains.

Recent development of lipoxygenase inhibitors as anti-inflammatory agents.

Inflammation is favorable in most cases, because it is a kind of body defensive response to external stimuli; sometimes, inflammation is also harmful, such as attacks on the body's own tissues. It could be that inflammation is a unified process of injury and resistance to injury. Inflammation brings extreme pain to patients, showing symptoms of rubor, swelling, fever, pain and dysfunction. As the specific mechanism is not clear yet, the current anti-inflammatory agents are given priority for relieving suffering of patients. Thus it is emergent to find new anti-inflammatory agents with rapid effect. Lipoxygenase (LOX) is a kind of rate-limiting enzyme in the process of arachidonic acid metabolism into leukotriene (LT) which mediates the occurrence of inflammation. The inhibition of LOX can reduce LT, thereby producing an anti-inflammatory effect. In this review, the LOX inhibitors reported in recent years are summarized, and, in particular, their activities, structure-activity relationships and molecular docking studies are emphasized, which will provide new ideas to design novel LOX inhibitors.

Synthesis and antibacterial evaluation of novel 11-O-aralkylcarbamoyl-3-O-descladinosylclarithromycin derivatives.

A series of novel 11-O-aralkylcarbamoyl-3-O-descladinosylclarithromycin derivatives were designed, synthesized and evaluated for their in vitro antibacterial activity. The results showed that the majority of the target compounds displayed potent activity against erythromycin-susceptible S. pyogenes, erythromycin-resistant S. pneumoniae A22072 expressing the mef gene and S. pneumoniae AB11 expressing the mef and erm genes. Besides, most of the target compounds exhibited moderate activity against erythromycin-susceptible S. aureus ATCC25923 and B. subtilis ATCC9372. In particular, compounds 11a, 11b, 11c, 11e, 11f and 11h were found to exert favorable antibacterial activity against erythromycin-susceptible S. pyogenes with the MIC values of 0.015-0.125 µg/mL. Furthermore, compounds 10e, 11a, 11b and 11c showed superior activity against erythromycin-resistant S. pneumoniae A22072 with the MIC values of 0.25-0.5 µg/mL. Additionally, compound 11c was the most effective against all the erythromycin-resistant S. pneumoniae strains (A22072, B1 and AB11), exhibiting 8-, 8- and 32-fold more potent activity than clarithromycin, respectively.

Novel 5-methyl-2-phenylphenanthridium derivatives as FtsZ-targeting antibacterial agents from structural simplification of natural product sanguinarine.

A novel series of 5-methyl-2-phenylphenanthridium derivatives were displayed outstanding activity against a panel of antibiotic-sensitive and -resistant bacteria strains compared with their precursor sanguinarine, ciprofloxacin and oxacillin sodium. Compounds 7 l, 7m and 7n were found to display the most effective activity against five sensitive strains (0.06-2 µg/mL) and three resistant strains (0.25-4 µg/mL). The kinetic profiles indicated that compound 7l possessed the strongest bactericidal effect on S. aureus ATCC25923, with the MBC value of 16 µg/mL. The cell morphology and the FtsZ polymerization assays indicated that these compounds inhibited the bacterial proliferation by interfering the function of bacterial FtsZ. The SARs showed that all the 4-methyl-substituted 5-methyl-2-phenylphenanthridium subseries could be further investigated as the FtsZ-targeting antibacterial agents.

Anterior chamber depth measurement in phakic and pseudophakic eyes.

PURPOSE: To compare anterior chamber depth (ACD) measurements using two non-contact optical devices, Pentacam and IOLMaster, and a contact device, ultrasonic A-scan in phakic and pseudophakic eyes. METHODS: Ninety phakic and 94 pseudophakic eyes were enrolled in this prospective study. The difference between ACD measurements by the three devices was analyzed using the repeated-measures analysis of variance, and agreement among the three measurements was investigated. The accuracy of detecting the anterior lens surface of the intraocular lens (IOL) with or without blue-blocker was also assessed. RESULTS: In phakic eyes, the Pentacam measured the deepest ACD with the smallest standard deviation (3.26 +/- 0.41, 3.20 +/- 0.45, and 3.12 +/- 0.44 mm measured by Pentacam, IOLMaster, and A-scan, respectively, p < 0.001). In contrast, the Pentacam measurement of ACD had the largest standard deviation in pseudophakic eyes (4.05 +/- 0.58, 4.06 +/- 0.46, and 3.81 +/- 0.41 mm by Pentacam, IOLMaster, and A-scan, respectively, p < 0.001). The Pentacam instrument failed to correctly identify the anterior lens surface in 26.4% of IOLs without blue-blocker and in 58.5% of blue light-filtering IOLs (p = 0.016). Manual correction of the Pentacam image and subsequent ACD measurement improved the agreement between Pentacam and the other two devices. After manual adjustment, the average ACD value increased, and the standard deviation decreased significantly (4.34 +/- 0.28 mm). CONCLUSIONS: ACD measurements by Pentacam, IOLMaster, and A-scan were in better agreement in phakic eyes when compared with pseudophakic eyes. In pseudophakic eyes, the 95% limits of agreements between Pentacam and IOLMaster as well as Pentacam and A-scan were unsatisfactory. IOLs with blue-blocker might interfere with ACD measurements. However, this error can be corrected manually in the Pentacam examination.

Intraocular lens power calculation using the IOLMaster and various formulas in eyes with long axial length.

PURPOSE: To evaluate the predictability of intraocular lens (IOL) power calculations using the IOLMaster (Carl Zeiss) and different IOL power calculation formulas in eyes with a long axial length (AL). SETTING: Department of Ophthalmology, Far Eastern Memorial Hospital, Taipei, Taiwan. METHODS: This study included 68 eyes with an AL longer than 25.0 mm that had phacoemulsification with IOL implantation. Preoperative AL and keratometric index measurements were obtained with the IOLMaster (Group 1) or, respectively, with applanation ultrasound and automatic keratometry (Group 2). The power of the implanted IOL was used to calculate the predicted postoperative spherical equivalence (SE) by various formulas: SRK/T, SRK II, and Holladay 1 (Groups 1 and 2) and Haigis (Group 1). The predictive accuracy of the formula was analyzed by comparing the mean difference between the actual and predicted postoperative SE; that is, the mean absolute error (MAE). RESULTS: The mean AL was significantly longer in Group 1 than in Group 2 (P = .03). The MAEs calculated by the SRK/T, SRK II, and Holladay 1 formulas were comparable between the 2 groups (P>.05). The lowest MAE was obtained using the IOLMaster data in the Haigis formula (P<.05). CONCLUSIONS: Although AL measured by the IOLMaster was longer than that measured by ultrasound, use of optical or ultrasound biometry data in the SRK/T, SRK II, and Holladay 1 formulas resulted in similar accuracy of IOL power prediction in eyes with higher myopia. The IOL power calculated using the Haigis formula predicted the best refractive outcome in long eyes.

Managing keratoconus with reverse-geometry and dual-geometry contact lenses: a case report.

PURPOSE: To present a case of keratoconus successfully managed with various rigid gas-permeable contact lenses with reverse-geometry and dual-geometry designs. METHODS: Case report. RESULTS: The steepest topographic keratometric readings of a 30-year-old woman with keratoconus were 62.18 diopters in the right eye and 54.70 diopters in the left eye. A conventional reverse-geometry lens worked well in the left eye. The more distorted right eye was fitted with a series of different reverse-geometry and dual-geometry lenses. Her visual acuity was 20/20 in each eye when she wore contact lenses during the day. Unaided vision was as good as 20/25+ in the right eye and 20/20 in the left eye for several hours after lens removal. No significant complication occurred during 42 months of follow-up. CONCLUSIONS: Keratoconus is a corneal disease characterized by progressive stromal thinning and ectasia, typically in the inferior cornea. Rigid gas-permeable contact lenses are the most common management option to improve vision. Corneal surgery, such as keratoplasty, is the next choice when contact lenses are ineffective or intolerable. The large overall diameter and contact area of reverse-geometry and dual-geometry lenses can assist in stabilizing the lenses on distorted corneas. These contact lenses may provide viable alternatives for management before corneal surgery.

Egr1 gene knockdown affects embryonic ocular development in zebrafish.

PURPOSE: To identify the changes in zebrafish embryonic ocular development after early growth response factor 1 (Egr1) gene knockdown by Egr1-specific translation inhibitor, morpholino oligonucleotides (MO). METHODS: Two kinds of Egr1-MO were microinjected separately with various dosages into one to four celled zebrafish embryos to find an optimal dose generating an acceptable mortality rate and high frequency of specific phenotype. Chordin-MO served as the positive control; a 5 mismatch MO of Egr1-MO1 and a nonspecific MO served as negative controls. We graded the Egr1 morphants according to their gross abnormalities, and measured their ocular dimensions accordingly. Western blot analysis and synthetic Egr1 mRNA rescue experiments confirmed whether the deformities were caused by Egr1 gene knockdown. Histological examination and three kinds of immunohistochemical staining were applied to identify glutamate receptor one expression in retinal ganglion cells and amacrine cells, to recognize acetylated alpha-tubulin expression which indicated axonogenesis, and to label photoreceptor cells with zpr-1 antibody. RESULTS: After microinjection of 8 ng Egr1-MO1 or 2 ng Egr1-MO2, 81.8% and 97.3% of larvae at 72 h postfertilization had specific defects, respectively. The gross phenotype included string-like heart, flat head, and deformed tail. The more severely deformed larvae had smaller eyes and pupils. Co-injection of 8 ng Egr1-MO1 and supplementary 12 pg synthetic Egr1 mRNA reduced the gross abnormality rate from 84.4% to 29.7%, and decreased the severity of deformities. Egr1 protein appeared in the wildtype and rescued morphants, but was lacking in the Egr1 morphants with specific deformities. Lenses of Egr1 morphants were smaller and had some residual nucleated lens fiber cells. Morphants' retinal cells arranged disorderly and compactly with thin plexiform layers. Immunohistochemical studies showed that morphants had a markedly decreased number of mature retinal ganglion cells, amacrine cells, and photoreceptor cells. Retinal axonogenesis was prominently reduced in morphants. CONCLUSIONS: The Egr1 gene plays an important role in zebrafish embryonic oculogenesis. Ocular structures including lens and retina were primitive and lacked appropriate differentiation. Such arrested retinal and lenticular development in Egr1 morphants resulted in microphthalmos.

Analysis of crystalline lens position.

PURPOSE: To study normal crystalline lens position to provide a comparative baseline for future studies of crystalline lens or intraocular lens shift. SETTING: Taipei Municipal Yang-Ming Hospital, Taipei, Taiwan. METHODS: A Scheimpflug anterior segment analyzer (EAS-1000, Nidek) was prospectively applied to measure the cycloplegic crystalline lens position in subjects who had not had previous ocular surgeries or who had been diagnosed previously with major ocular diseases such as glaucoma, retinal detachment, or cataract. Measurements included anterior chamber depth (ACD), magnitudes, direction of lens decentration, and lens tilt. Refractive error was measured with an autorefractometer, and multiple linear regression was used to verify revealed relationships. The aging effect was determined with the Pearson correlation test. RESULTS: Thirty-nine eyes of 30 subjects (15 men, median age 13 years, range 4 to 53 years) were included. The center of the anterior lens surface was decentered 0.25 mm superotemporally. The lens tilted 2.85 degrees with the anterior lens surface facing the inferotemporal quadrant. The mean ACD was 3.26 mm; it tended to increase before subjects reached 20 years of age and to decrease thereafter. With age, the lens tended to exhibit less tilt. Lens position did not affect the spherical equivalent or the magnitude of astigmatism. CONCLUSION: The crystalline lens was not aligned perfectly along the visual axis, but its effect on refraction was limited.

Clinical characteristics and leakage of functioning blebs after trabeculectomy with mitomycin-C in primary glaucoma patients.

PURPOSES: To describe the clinical characteristics of functioning blebs in Japanese glaucoma patients after primary trabeculectomy with adjunctive mitomycin-C (MMC) and to correlate their associations with postoperative bleb leakage. DESIGN: A prospective, observational case series. PARTICIPANTS: One hundred sixty-two glaucoma patients who had undergone primary trabeculectomy with MMC at the University of Tokyo Hospital at least 3 months before were examined between December 1997 and February 1998. METHODS: A predesigned data form was completed at each visit. Ophthalmologic examinations included Goldmann applanation tonometry, slit-lamp examination, and Seidel tests with and without digital ocular pressure (DOP). MAIN OUTCOME MEASURES: Properties of the functioning bleb, including bleb appearance, thickness of bleb wall, dimensions of bleb and avascular area, and leakage status with and without DOP. RESULTS: Of 162 Japanese patients, 162 eyes with functioning blebs were included. There were no differences in bleb characteristics among the different types of primary glaucoma. With a long postoperative duration, blebs tended to be thinner (P = 0.024). With DOP, the leaking rate increased from 3.1% to 5.6%, and the oozing rate increased from 11.1% to 35.8% (P < 0.001). Logistic regression analysis indicated that the larger the avascular area, the more likely the bleb leaked without DOP (P = 0.016). When DOP was applied, leakage was more likely to occur in the blebs with a long postoperative duration (P = 0.002) or with a large avascular area (P < 0.001). CONCLUSIONS: The clinical characteristics of filtering blebs were similar in Japanese patients with different types of primary glaucoma. Blebs with a large avascular area were associated with a higher risk of bleb leakage. Attention to the increased chance of leakage induced by DOP is important, especially for blebs with a long postoperative duration. Ophthalmologists should be aware of late bleb-related complications in addition to bleb function.