Transcriptional repression of PTEN in neural cells using CRISPR/dCas9 epigenetic editing.

After damage to the adult mammalian central nervous system (CNS), surviving neurons have limited capacity to regenerate and restore functional connectivity. Conditional genetic deletion of PTEN results in robust CNS axon regrowth, while PTEN repression with short hairpin RNA (shRNA) improves regeneration but to a lesser extent, likely due to suboptimal PTEN mRNA knockdown using this approach. Here we employed the CRISPR/dCas9 system to repress PTEN transcription in neural cells. We targeted the PTEN proximal promoter and 5' untranslated region with dCas9 fused to the repressor protein Krüppel-associated box (KRAB). dCas9-KRAB delivered in a lentiviral vector with one CRISPR guide RNA (gRNA) achieved potent and specific PTEN repression in human cell line models and neural cells derived from human iPSCs, and induced histone (H)3 methylation and deacetylation at the PTEN promoter. The dCas9-KRAB system outperformed a combination of four shRNAs targeting the PTEN transcript, a construct previously used in CNS injury models. The CRISPR system also worked more effectively than shRNAs for Pten repression in rat neural crest-derived PC-12 cells, and enhanced neurite outgrowth after nerve growth factor stimulation. PTEN silencing with CRISPR/dCas9 epigenetic editing may provide a new option for promoting axon regeneration and functional recovery after CNS trauma.

Preservation of fruit and vegetable discards with sodium metabisulfite.

Two series of experiments were performed to investigate the aerobic preservation of fruit and vegetable discards (FVD) using sodium metabisulfite (SMB). In Exp. 1, metabisulfite was applied at 0, 2, 4, 6, and 8 g/kg FVD for 0, 3, 6, 9, and 12 d. Metabisulfite treatment at 6 and 8 g/kg FVD was highly effective in controlling putrefaction and preserving the nutrient components for 6 and 9 d, respectively. In the pilot-scale experiment (Exp. 2), SMB was applied at 0 and 8 g/kg FVD in a 600-L bucket for 0, 6, and 9 d in an outdoor environment. The SMB treatment was highly effective in maintaining the integrity and freshness of FVD, suppressing microbial proliferation, and preserving the nutrient constituents. Under the conditions of this study, SMB effectively preserved FVD in an aerobic environment, enabling their more efficient long-term recycling through livestock feed or development of value-added products.

Measuring the effect of femoral malrotation on knee joint biomechanics for total knee arthroplasty using computational simulation.

OBJECTIVES: Malrotation of the femoral component can result in post-operative complications in total knee arthroplasty (TKA), including patellar maltracking. Therefore, we used computational simulation to investigate the influence of femoral malrotation on contact stresses on the polyethylene (PE) insert and on the patellar button as well as on the forces on the collateral ligaments. MATERIALS AND METHODS: Validated finite element (FE) models, for internal and external malrotations from 0° to 10° with regard to the neutral position, were developed to evaluate the effect of malrotation on the femoral component in TKA. Femoral malrotation in TKA on the knee joint was simulated in walking stance-phase gait and squat loading conditions. RESULTS: Contact stress on the medial side of the PE insert increased with internal femoral malrotation and decreased with external femoral malrotation in both stance-phase gait and squat loading conditions. There was an opposite trend in the lateral side of the PE insert case. Contact stress on the patellar button increased with internal femoral malrotation and decreased with external femoral malrotation in both stance-phase gait and squat loading conditions. In particular, contact stress on the patellar button increased by 98% with internal malrotation of 10° in the squat loading condition. The force on the medial collateral ligament (MCL) and the lateral collateral ligament (LCL) increased with internal and external femoral malrotations, respectively. CONCLUSIONS: These findings provide support for orthopaedic surgeons to determine a more accurate femoral component alignment in order to reduce post-operative PE problems.Cite this article: K-T. Kang, Y-G. Koh, J. Son, O-R. Kwon, C. Baek, S. H. Jung, K. K. Park. Measuring the effect of femoral malrotation on knee joint biomechanics for total knee arthroplasty using computational simulation. Bone Joint Res 2016;5:552-559. DOI: 10.1302/2046-3758.511.BJR-2016-0107.R1.

Viral vector-based improvement of optic nerve regeneration: characterization of individual axons' growth patterns and synaptogenesis in a visual target.

Lack of axon growth ability in the central nervous system poses a major barrier to achieving functional connectivity after injury. Thus, a non-transgenic regenerative approach to reinnervating targets has important implications in clinical and research settings. Previous studies using knockout (KO) mice have demonstrated long-distance axon regeneration. Using an optic nerve injury model, here we evaluate the efficacy of viral, RNA interference (RNAi) and pharmacological approaches that target the phosphatase and tensin homolog (PTEN) and signal transducer and activator of transcription-3 pathways to improve long-distance axon regeneration in wild-type mice. Our data show that adeno-associated virus (AAV) expressing short hairpin RNA (shRNA) against PTEN (shPTEN) enhances retinal ganglion cell axon regeneration after crush injury. However, compared with the previous data in PTEN KO mice, AAV-shRNA results in a lesser degree of regeneration, likely due to incomplete gene silencing inherent to RNAi. In comparison, an extensive enhancement in regeneration is seen when AAV-shPTEN is coupled to AAV encoding ciliary neurotrophic factor (CNTF) and to a cyclic adenosine monophosphate (cAMP) analog, allowing axons to travel long distances and reach their target. We apply whole-tissue imaging that facilitates three-dimensional visualization of single regenerating axons and document heterogeneous terminal patterns in the targets. This shows that some axonal populations generate extensive arbors and make synapses with the target neurons. Collectively, we show a combinatorial viral RNAi and pharmacological strategy that improves long-distance regeneration in wild-type animals and provide single fiber projection data that indicates a degree of preservation of target recognition.

Comparison of diagnostic methods for onychomycosis, and proposal of a diagnostic algorithm.

BACKGROUND: Traditionally, the gold standard for diagnosis of onychomycosis has been the combination of direct microscopy with potassium hydroxide (KOH) staining and fungal culture. However, several studies have suggested that periodic-acid-Schiff (PAS) staining of nail-plate clippings may be a very sensitive method for the diagnosis of onychomycosis. AIM: To compare the sensitivities of direct microscopy with KOH, fungal culture and PAS staining of nail-plate clippings, and to define an efficient, high-yield and cost-effective diagnostic strategy for the diagnosis of onychomycosis in the clinical setting. METHODS: We evaluated a total of 493 patients with clinically suspected onychomycosis. Group A comprised 400 patient samples, evaluated using fungal culture and PAS stain, while group B comprised 93 patient samples evaluated using KOH, fungal culture and PAS. Diagnosis of onychomycosis was defined as clinical morphology plus at least one positive test result. RESULTS: In group A, sensitivities of fungal culture and PAS were 49.5% and 93.1% (P < 0.005), respectively. In group B, the most sensitive single test was PAS (88.2%) followed by KOH (55.9%) and fungal culture (29.4%). The combination of fungal culture and PAS (94.1%) was significantly (P < 0.001) more sensitive than that of KOH and culture (72.1%). CONCLUSION: PAS staining of nail clippings is much more sensitive than KOH and fungal culture for the diagnosis of onychomycosis. Based on our results, we propose a diagnostic algorithm for onychomycosis that takes into consideration the sensitivity, cost-effectiveness and necessary time for each test.

Ensiling Characteristics and the In situ Nutrient Degradability of a By-product Feed-based Silage.

This study was conducted to evaluate the ensiling characteristics and the in situ degradability of a by-product feed (BF)-based silage. Before ensilation, the BF-based mixture was composed of 50% spent mushroom substrate, 21% recycled poultry bedding, 15% ryegrass straw, 10.8% rice bran, 2% molasses, 0.6% bentonite, and 0.6% microbial inoculant on a wet basis and ensiled for up to 4 weeks. The BF-based silage contained on average 39.3% moisture, 13.4% crude protein (CP), and 52.2% neutral detergent fiber (NDF), 49% total digestible nutrient, and 37.8% physically effective NDF1.18 on a dry matter (DM) basis. Ensiling the BF-based silage for up to 4 weeks affected (p<0.01) the chemical composition to a small extent, increased (p<0.05) the lactic acid and NH3-N content, and decreased (p<0.05) both the total bacterial and lactic acid bacterial counts from 10(9) to 10(8) cfu/g when compared to that before ensiling. These parameters indicated that the silage was fermented and stored well during the 4-week ensiling period. Compared with rice or ryegrass straws, the BF-based silage had a higher (p<0.05) water-soluble and filterable fraction, a lower insoluble degradable DM and CP fraction (p<0.05), a lower digestible NDF (p<0.05) fraction, a higher (p<0.05) DM and CP disappearance and degradability rate, and a lower (p<0.05) NDF disappearance and degradability rate. These results indicated that cheap, good-quality BF-based roughage could be produced by ensiling SMS, RPB, rice bran, and a minimal amount of straw.

A randomized, 'head-to-head' pilot study comparing the effects of etanercept monotherapy vs. etanercept and narrowband ultraviolet B (NB-UVB) phototherapy in obese psoriasis patients.

BACKGROUND: Etanercept is a tumour necrosis factor-alpha antagonist used for the treatment of moderate-to-severe psoriasis. Current opinion suggests that etanercept may have reduced efficacy in obese patients. Narrowband ultraviolet B (NB-UVB) phototherapy is unaffected by body weight and the addition of NB-UVB to etanercept therapy may supplement the efficacy of etanercept in these patients. OBJECTIVE: To evaluate the efficacy and safety of NB-UVB phototherapy when administered in conjunction with 50 mg of etanercept once weekly in the treatment of obese patients with moderate-to-severe plaque psoriasis. METHODS: Thirty psoriasis patients with a body mass index (BMI) greater than 30 were enrolled into this randomized, 'head-to-head' comparison study. All subjects received 50 mg of etanercept twice weekly for 12 weeks and then randomized to receive either etanercept monotherapy or combination etanercept and NB-UVB three times weekly for an additional 12 weeks. Treatment response was evaluated using Psoriasis Area and Severity Index (PASI), body surface area (BSA) and Physician's Global Assessment (PGA) scores. RESULTS: Twenty-five subjects completed the study. At 12 weeks, 48% of all patients achieved PASI 75. By Week 24, 62.5% of all patients achieved PASI 75. Patients in the etanercept monotherapy and combination etanercept and NB-UVB phototherapy arms had similar rates of achieving PASI 75 (46.7% vs. 53.3% of each group, respectively). CONCLUSION: Combination etanercept and NB-UVB has similar efficacy to etanercept monotherapy in obese patients. This result indicates that even in the setting of obesity, the majority of patients respond well to etanercept, with or without NB-UVB.

A review of monochromatic excimer light in vitiligo.

Phototherapy is a mainstay of vitiligo treatment and has varying rates of efficacy. Narrowband ultraviolet (UV) B (NB-UVB) and UVA have been used for decades, but it is only recently that monochromatic excimer light (MEL) was developed for use in dermatology and adapted for the treatment of vitiligo. The specific 308-nm radiation wavelength is delivered in a targeted form by the xenon-chloride excimer laser and is also available in an incoherent form that is commonly referred to as the excimer lamp. MEL administered by both laser and lamp has shown efficacy superior to NB-UVB for the treatment of vitiligo and induces more changes at the cellular level than conventional UVB modalities. The excimer laser is effective in adults and children with vitiligo in all skin types as monotherapy or in combination with other established vitiligo therapeutics. Treatment regimens studied included excimer laser two to three times weekly for up to 36 weeks. Patients commonly achieved > 75% repigmentation. The laser has also been used in combination with topical corticosteroids, calcineurin inhibitors and vitamin D analogues, as well as surgery, thus further expanding treatment options for patients with vitiligo. The excimer lamp has been used for treatments one to three times a week for up to 24 weeks and was found to be equal to excimer laser in a head-to-head comparison. It has also been used in combination with topical corticosteroids and oral vitamin E. Both MEL modalities have a limited adverse side-effect profile. Long-term effects are yet to be determined; however, based on available data on UVB phototherapy as well as the properties of MEL devices, there is probably only a minimal increased malignancy risk.

Comparative rapid onset of efficacy between doxazosin gastrointestinal therapeutic system and tamsulosin in patients with lower urinary tract symptoms from benign prostatic hyperplasia: a multicentre, prospective, randomised study.

AIMS: To compare the rapidity of improvement in lower urinary tract symptoms (LUTS) for the doxazosin gastrointestinal therapeutic system (GITS) and tamsulosin in benign prostatic hyperplasia (BPH) patients. METHODS: A total of 207 patients were randomised to one of two groups for a 12-week daily treatment with doxazosin-GITS 4 mg or tamsulosin 0.2 mg. The primary end-point was to compare the early onsets of efficacy between the two drugs. This was assessed by analysing the changes from baseline in the total International Prostate Symptom Score (IPSS) in the early period of treatment. Secondary aims were to compare improvements in obstructive/irritative subscore and quality of life (QoL) score between the two groups, and to evaluate the adverse events (AEs) with the drugs. RESULTS: After 12 weeks of treatment, both groups showed significant improvements in IPSS scores (total, obstructive and irritative subscores, QoL score) from baseline (p < 0.0001). However, the doxazosin-GITS group showed significantly greater improvements in total IPSS and obstructive subscore than the tamsulosin group in the early period (p < 0.05). Improvements in irritative subscore (within 4 weeks) and QoL score (during 12 weeks) were not significantly different between the groups. The incidences of AEs were similar between the groups. CONCLUSION: In this study, doxazosin-GITS showed significantly more rapid onset of efficacy and similar AEs compared with tamsulosin in BPH patients with LUTS. We believe this will probably improve patient compliance. Future studies with a larger number of patients and a longer follow-up period will be required to confirm this.

Molecular characterization of the human ABO blood group orthologus system in pigs.

The selection and use of animals with blood group 0 in the process of transplanting pig organs or tissues into humans can positively contribute to the control of acute immune rejection due to differences in blood groups. Exon-specific PCRs for the porcine blood group A transferase gene against genomic DNA from either blood group A or 0 animals resulted in the amplification failure of the A0 blood group gene exon 8 from blood group 0 animals. To characterize the genetic abnormality in the genome of blood group 0 animals, we screened bacterial artificial chromosome (BAC) clones from a Korean native pig BAC library which had the blood group 0 allele, and carried out shotgun sequencing. The analysis showed that the 0 allele has a large deletion between exon 7 of the A0 blood group gene and the neighbouring SURF6. We also showed that the ABO blood group antigens in humans and the A0 blood group antigens in pigs are coded by mutations within the orthologous glycosyltransferase gene. In addition, we developed a multiplex genotyping method for the porcine A0 blood group gene.

Effects of α-blocker 'add on' treatment on blood pressure in symptomatic BPH with or without concomitant hypertension.

We investigated the effects of 'add on' treatment of α-blocker (AB) on blood pressure (BP) and the safety of ABs in men with symptomatic BPH with or without hypertension. We retrospectively reviewed 2,924 BPH outpatients who took ABs at our institution between 2005 and 2009. BPH symptom severity, prostate volume and BP were determined for 953 patients with their baseline data. BP level and International Prostate Symptom Score were measured within 2 months after AB treatment. Patients were assigned to four groups: group 1 had 272 normotensive patients on concomitant hypertensive medication; group 2 had 293 normotensive patients not on the medication; group 3 had 216 hypertensive patients on concomitant medication; and group 4 had 172 hypertensive patients not on the medication. The addition of AB lowered the mean systolic BP by 16.6 mm Hg for group 3 and by 8.6 mm Hg for group 4, and diastolic BP by 18.0 mm Hg for group 3 (P<0.05). However, normotensive groups on entry, irrespective of antihypertensive medication, showed no significant BP changes from baseline after AB medication. In the hypertensive groups on entry, the doxazosin gastrointestinal therapeutic system (GITS) resulted in significant reductions in systolic BP from 142.2 to 134.9 mm Hg and in diastolic BP from 97.6 to 84.6 mm Hg. When analyzed by AB regimen, the incidence of BP-related adverse events was comparable. AB therapy for BPH can have an appropriate and beneficial effect on BP, especially in baseline hypertensive patients. Doxazosin GITS treatment resulted in optimal management of BP within the normal range, especially in pharmacologically or physiologically hypertensive patients.

Identification and characterization of a novel mouse and human MOPT gene containing MORN-motif protein in testis.

A novel testis-derived membrane occupation and recognition nexus (MORN)-motif protein was identified in mouse testis (MOPT) by subtraction screening methods and found to be localized on chromosome 17E3, spanning approximately 7kb. Sequence analysis showed that MOPT contains 669 base pair nucleotides of open reading frame and the corresponding 79 amino acids. The protein is predicted to have theoretical molecular mass of 9000 Da and an expected isoelectric point of 5.8 and seems to have unique sequences except for MORN-motif domain. The transcript of MOPT is highly and specifically expressed in adult testis as well as skeletal muscle. Moreover, MOPT transcript and protein are confined mainly to round and elongated spermatids, except for a few individual dispersed spermatocytes, and increase in abundance at subsequent stages. MOPT first appeared in the proacrosomic vesicles of the early Golgi phase spermatids and was translocated from the head cap of elongated spermatid to the nucleus of mature spermatozoa at the final stage of spermiogenesis. Our study suggests that MOPT may play an important role in dynamic regulation of acrosome biogenesis during late spermiogenesis.

Modeling and Measuring the Effects of Mutual Impedance on Multi-Cell CMUT Configurations.

This paper presents a numerical method for calculating the frequency response of a CMUT with a large number of cells. In a multi-cell configuration, commonly found in CMUTs, each cell is affected by the acoustic loading from neighboring cells. Thus, for an accurate model of a multi-cell CMUT element it is better to consider the mutual acoustic impedance instead of the acoustic impedance of a single cell only. We calculate the velocity of every cell (plate movement) simultaneously, with the mutual impedance effects taken into account. The model predicts that the cells exhibit different frequency responses, based on their locations in the element. We used a laser interferometer to validate the model by measuring the displacement response of a CMUT immersed in vegetable oil. The device has 169 circular cells (single crystal silicon plates, 500 nm thick, 21 µm radii) placed in a hexagonal cell arrangement. The measurement results agree well with the numerical results. The computation time of our method is significantly shorter than finite element based calculations. Our model can be used for finding optimized cell configurations for CMUTs utilized in various applications such as medical imaging and therapeutic treatment.

Ternary complex formation of Eu(III) with o-phthalate in aqueous solutions.

Ternary hydroxo complex formation of Eu(III) with o-phthalate was investigated by potentiometry and fluorescence spectrophotometry. Curves of the equilibrium pH versus the amount of NaOH added showed that the pH value starting to form a Eu(III) precipitate was decreased due to the formation of a ternary hydroxo complex, EuOHL(s) (L = phthalate). The formation of EuOHL(s) was qualitatively confirmed by the enhancement of the fluorescence intensity of Eu(III) in the precipitate with the light absorbed by phthalate, and was quantitatively confirmed by the measurement of the amounts of Eu(III), OH(-) and phthalate included in the precipitate. The solubility product of EuOHL(s) was determined as pK(sp)(0) = 15.6+/-0.4. Characteristic features in the fluorescence spectra and the solubility product of the Eu(III)-phthalate complex were compared with those of the Eu(III)-PDA (PDA = pyridine-2,6-dicarboxylate) complex. The fluorescence intensity of the EuL(+) complex of L = PDA was about 11 times stronger than that of L = phthalate. The origin of the difference in the fluorescence intensity is discussed based on the intramolecular energy transfer effect from the lowest triplet energy level of the ligand to the resonance energy level of Eu(III).

Mechanism of azithromycin treatment on gingival overgrowth.

Azithromycin is effective for the remission of cyclosporine A-induced gingival overgrowth (CIGO) in persons who have undergone renal transplant. To explain its mechanism in alleviating the clinical symptoms of these individuals, we examined the effect of azithromycin on cell proliferation and collagen turnover modified by cyclosporin A in human gingival fibroblasts from healthy persons and from persons who had undergone renal transplant. Cyclosporin A-induced proliferation of renal transplant fibroblasts and normal fibroblasts was inhibited by azithromycin. Azithromycin elevated the reduced metalloproteinase (MMP)-1 and MMP-2 activities in cyclosporine A-treated renal transplant fibroblasts and normal fibroblasts. In cyclosporine A-treated renal transplant fibroblasts, azithromycin blocked the accumulation of total collagen in culture media and the increase in type I collagen mRNA level, but recovered the reduced MMP-2 mRNA level to the control. These results suggest that azithromycin may improve CIGO by blocking cyclosporine A-induced cell proliferation and collagen synthesis, and by activating MMP-2 in gingival fibroblasts of persons with cyclosporine A-induced gingival overgrowth.

Correlation of maximum flexion with clinical outcome after total knee replacement in Asian patients.

This study aimed to determine the correlation between the amount of maximum flexion and the clinical outcome in 207 Koreans (333 knees) undergoing total knee replacement. The association of maximum flexion with clinical outcome was evaluated one year postoperatively using three scoring systems; the American Knee Society score, Western Ontario McMaster Universities Osteoarthritis index and the Short Form-36. The mean maximum flexion decreased post-operatively at 12 months from 140.1 degrees (60 degrees to 160 degrees ) to 133.0 degrees (105 degrees to 150 degrees ). Only the social function score of the Short Form-36 correlated significantly with maximum flexion (correlation coefficient = 0.180, p = 0.039). In comparative analyses of subgroups divided by a maximum flexion of 120 degrees , we found no significant differences in any parameters except the social function score of the Short Form-36 (41.9 vs 47.3, p = 0.031). Knees with a maximum flexion of more than 135 degrees had a better functional Western Ontario McMasters Universities Osteoarthritis index score than knees with maximum flexion of 135 degrees or less (17.5 vs 14.3, p = 0.031). We found only weak correlation between the postoperative maximum flexion and the clinical parameters for pain relief, function and quality of life, even in Korean patients. Efforts to increase post-operative maximum flexion should be exercised with caution until concerns relating to high-flexion activities are sufficiently resolved.

Systemic herpes simplex virus infection following cadaveric renal transplantation: a case report.

Herpes simplex virus (HSV) infection usually occurs in immunocompromised or severely debilitated patients. It is not so common in patients with renal transplants. The diagnosis can only be made histologically. It usually occurs during or shortly after treatment of graft rejection with high-dose steroids. We have recently experienced a case of HSV esophagitis and nephropathy in the renal allograft biopsy, which was identified by histology, immunostaining, and electron microscopy. A 43-year-old woman underwent cadaveric renal transplantation with cyclosporine and prednisolone treatment. Twelve months later, she developed renal insufficiency and proteinuria. Allograft renal biopsy showed some evidence of acute rejection. She was treated with 3 successive days of methylprednisolone (1.0 g/d) intravenously and continued tapering of steroids. Three weeks after steroid pulse therapy, she had throat pain, oral cavity ulcer, dysphagia, and febrile sensation. Esophagoscopy revealed multiple confluent ulcers in the whole esophagus, and biopsy showed enlarged epithelial cells with prominent nuclei. Immunohistochemically, the epithelial cells were positive with a monoclonal antibody to HSV type 1. She was started on acyclovir intravenously, which was continued for a week. After a week, her symptoms began to improve and repeat endoscopy showed no residual esophagitis. A renal allograft infection with HSV can persist in heavily immunosuppressed patients with recurrent rejection episodes. HSV mainly affects tubular cells causing necrosis, a major reason for functional deterioration. A biopsy is required for diagnosis.

Ring-Sp1 decoy oligonucleotide effectively suppresses extracellular matrix gene expression and fibrosis of rat kidney induced by unilateral ureteral obstruction.

Tubulointerstitial fibrosis is the consequence of an injury characterized by the accumulation of excess collagen and other extracellular matrix components, resulting in the destruction of the normal kidney architecture and subsequent loss of function. A transcription factor Sp1, originally described as a ubiquitous transcription factor, is involved in the basal expression of extracellular matrix genes and may, therefore, be important in fibrotic processes. Here, we report on the design of a ring-Sp1 decoy oligonucleotide, containing the consensus Sp1 binding sequence in a single decoy molecule without an open end, to create a novel therapeutic strategy for fibrosis. The ring-Sp1 decoy oligonucleotide is highly resistant to degradation by nucleases or serum compared to the conventional phosphorothioated double-stranded Sp1 decoy oligonucleotide, and effectively suppressed the expression of transforming growth factor-beta1 and fibronectin, the binding of Sp1 to the promoter region of these genes, and proliferation in response to serum in normal rat kidney fibroblasts. Moreover, treatment with the ring-Sp1 decoy in vivo significantly attenuates extracellular matrix gene expression in the rat kidney in which a unilateral ureteral obstruction had been induced. These results suggest that the ring-Sp1 decoy oligonucleotide represents promising therapeutic alternative to the conventional treatment of fibrotic disorders.

Ultrastructural evaluation of the protective effect of nitroglycerin in preservation-reperfusion injury of rat lungs.

AIM OF STUDY: Nitric oxide (NO) has been reported as a favorable protective supplement in donor lung preservation, but related ultrastructural studies are rare in the literature. This study was performed to assess the ultrastructural changes and to evaluate the protective effect of NO as donor nitroglycerin (NTG) treatment of ischemia-reperfusion injury in rat lungs. MATERIALS AND METHODS: Fifteen Sprague-Dawley rats weighing 300 to 350 g were used in this study. The NTG group (n = 5) used intravenous administration followed by mixture in the University of Wisconsin (UW) solution. For the non-NTG group (n = 5), we injected the same amount of normal saline intravenously followed by admixture in the UW solution. The heart-lung blocks were removed, weighed, and kept in UW solution for 24 hours at 10 degrees C. Reperfusion using human blood diluted in Krebs-Hensleit solution was done for 60 minutes. For the control group (n = 5), we injected the same amount of normal saline intravenously, and removed the lungs with no preservation and reperfusion procedures. RESULTS: The non-NTG group showed multiple patchy areas of alveolar collapse with marked swelling and destruction of type I epithelial cells, loss of type II cell surfactant granules, endothelial swelling and papillary projection, interstitial edema, and alveolar macrophages with active phagocytosis of the destroyed materials. The NTG group showed similar ultrastructural changes, but in a lesser severity compared with the non-NTG group. CONCLUSION: Administration of the NTG reduced the ischemia-reperfusion injury in the rat donor lungs. Ultrastructural examination was an effective tool to evaluate the protective effect of NTG in ischemia-reperfusion procedures of donor lungs.

BK virus infection in kidney transplant recipients.

INTRODUCTION: Nephropathy associated with the polyomavirus type BK virus (BKV) has emerged as a cause of allograft failure linked to immunosuppressive regimens containing tacrolimus or mycophenolate mofetil (MMF). The outcome in BKV nephropathy is generally unfavorable, namely 50% of patients lose graft function. We herein report nine cases of BKV nephropathy after kidney transplantation. METHODS: From October 1998 to May 2003, 138 of 169 consecutive kidney transplant patients received tacrolimus-based immunosuppression, and 31 received cyclosporine-based immunosuppression. Additionally, 88.2% of the patients received mycophenolate mofetil (MMF). The diagnosis of BK infection was made by the presence of decoy cells in the urine and by allograft biopsy. RESULTS: There were nine cases of BKV nephropathy in kidney transplant recipients, an incidence of 5.3%. All patients with BKV nephropathy received tacrolimus, MMF, and steroids. The median time to diagnosis of BKV infection was 7.8 months after transplantation. All patients experienced an elevated serum creatinine, which stabilized or decreased in seven patients with altered or decreased immunosuppression. After a mean follow-up of 11.1 months, 2 (22.2%) of nine patients lost the graft. CONCLUSION: Because BKV nephropathy is a rare but serious complication after kidney transplantation, it should be included in the clinical differential of transplant dysfunction. In the absence of documented antiviral treatment, early diagnosis and judicious use of immunosuppressive agents is indicated to minimize the occurrence of BKV infection.