Acoustic Radiation Force Impulse Imaging of the Transplant Kidney: Correlation Between Cortical Stiffness and Arterial Resistance in Early Post-transplant Period.

BACKGROUND: Acoustic radiation force impulse (ARFI) imaging is a noninvasive imaging modality for quantitative assessment of tissue stiffness. This study utilized ARFI imaging to assess the stiffness of a transplant renal cortex within the first month after renal transplantation and to explore the correlation between the cortical stiffness and arterial resistance of the transplant kidney. METHODS: Forty renal transplant recipients (male/female = 26/14; mean age: 45.3 years; deceased donor/living related donor = 27/13) were included in this study. ARFI imaging with virtual touch tissue imaging quantification was applied to assess the stiffness of the transplant renal cortex by using a linear ultrasound transducer. Arterial resistance was acquired by spectral Doppler examination of the main artery and intrarenal arteries of the transplant kidney using a curvilinear ultrasound transducer. RESULTS: The stiffness of transplant renal cortex was expressed as shear wave velocity (m/s). The mean value of cortical stiffness was 3.19 ± 1.01 m/s (range: 1.55-5.54). The stiffness of transplant renal cortex was positively correlated with the resistance index of the main renal artery (r = 0.55, P = .001), segmental artery (r = 0.43, P = .005), and interlobar artery (r = 0.42, P = .006). CONCLUSION: The stiffness of a transplant renal cortex is positively correlated with the arterial resistance of the renal transplant in the early post-transplant period. This result indicates that, in addition to renal fibrosis, the stiffness of the transplant renal cortex is also influenced by the hemodynamics of the transplant kidney.

Increased Stiffness of the Remnant Right Lobe Liver After Left Lobectomy or Lateral Segmentectomy in Donors of Living-Donor Liver Transplantation.

BACKGROUND: Liver stiffness is associated with the degree of fibrosis along with other factors. Abrupt change of liver perfusion after hepatectomy is one such factor. In this study, we performed ultrasound elastography to explore the stiffness of the right lobe liver before and after hepatectomy in donors who underwent resection of left lobe or lateral segment of liver. METHODS: A total of 32 left lobe liver donors (18 male and 14 female; age range, 21-55 years; mean age, 35.1 years; 19 left lobectomy with middle hepatic reserved for graft and 13 lateral segmentectomy with middle hepatic vein reserved in the remnant liver) were included in this study. Liver stiffness was measured by means of ultrasound elastography with the use of acoustic radiation force impulse imaging. Stiffness of the right lobe liver was obtained by means of right intercostal approach. RESULTS: The stiffness of remnant right lobe liver significantly increased after hepatectomy (1.24 ± 0.18 vs 1.10 ± 0.13 m/s; P = .001). Donors of left lobe liver showed higher stiffness in the remnant right lobe liver compared with donors of lateral segment (1.30 ± 0.18 vs 1.15 ± 0.14 m/s; P = .027). There was no significant correlation between the remnant right lobe liver stiffness, postoperative liver function, and flow parameters of hepatic artery and portal vein. CONCLUSIONS: The stiffness of remnant liver significantly increased after hepatectomy. Furthermore, the stiffness was higher in donors undergoing left lobectomy compared with those undergoing lateral segmentectomy.

[Association study between candidate genes involved in cell-cell adhesion and non-syndromic cleft lip with or without cleft palate in Chinese population].

OBJECTIVE: To explore the association and gene-environment interaction between single nucleotide polymorphisms (SNPs) involved in cell-cell adhesion and non-syndromic cleft lip with or without cleft palate (NSCL/P) among Chinese population. METHODS: A total of 806 NSCL/P trios were drawn by an international consortium, which conducted a genome-wide association study (GWAS) using a case-parent trio design to investigate genes affecting risks to NSCL/P. The transmission disequilibrium test (TDT) was used to explore the association between cell-cell adhesion genes, including CDH1, CTNNB1, PVRL1, PVRL2, PVRL3, ACTN1, VCL, LEF1, and NSCL/P. Conditional Logistic regression models were used to estimate effects on risk of exposed and unexposed children. Four common maternal exposures including maternal smoking, environmental tobacco smoke, alcohol consumption and multivitamin supplementation during pregnancy were included in this study. RESULTS: A total of 226 SNP markers were tested after quality control in this study. Although 23 SNPs in three genes (CTNNB1, CDH1, ACTN1) showed nominal significant association with NSCL/P in the TDT (P<0.05).There were no significant evidence of linkage and association that remained in the transmission disequilibrium test after Bonferroni correction(P>0.000 2). Tests for gene-environment interaction yielded significant results between rs743127 in ACTN1 and environmental tobacco smoke (P=0.000 1) with an estimated OR (case|G and E)=2.00(95%CI: 1.23-3.26) and OR (case|G no E)=0.59 (95%CI: 0.38-0.90). Among the lower P value results in gene-environment tests, there were no significant results between rs1475034, rs370535, rs2273419 in ACTN1, rs106871 in CTNNB1 and environmental tobacco smoke interaction. There were also no significant results between rs7634000, rs2971366, rs2634553, rs1489032, rs7624812 in PVRL3 and multivitamin supplementation during pregnancy in gene-environment tests(P>0.000 2). CONCLUSION: There is no association between cell-cell adhesion genes, including CDH1, CTNNB1, PVRL1, PVRL2, PVRL3, ACTN1, VCL, LEF1, and NSCL/P when the genes are considered alone. But our results suggest that SNPs in ACTN1 may influence the risk to NSCL/P through gene-environment interaction.

Risk factors for methicillin-resistant Staphylococcus aureus skin and soft-tissue infections in outpatients in Taiwan.

Information on the risk factors for community-associated skin and soft-tissue infections (SSTIs) due to methicillin-resistant Staphylococcus aureus in Asian populations is scarce. To this end we performed a case-control study of patients treated at two hospital-affiliated outpatient clinics in Taiwan to determine potential risk factors for MRSA SSTIs. S. aureus was isolated from 39 of 100 eligible patients, and 74% were MRSA. Apart from resistance to clindamycin and erythromycin, most MRSA isolates were susceptible to appropriate antimicrobials. The significant risk factors identified by multivariate analysis for MRSA SSTIs were male gender (P = 0·09), nasal carriage of MRSA (P = 0·02), exposure to an individual who had surgery within a year before infection (P = 0·02), and antibiotic treatment for SSTI in the year before infection (P = 0·04). The identification of such factors may assist provision of appropriate treatment to patients with suspected S. aureus SSTIs particularly in Taiwan.

Non-volatile organic transistor memory devices using the poly(4-vinylpyridine)-based supramolecular electrets.

Supramolecular electrets consisting of poly(4-vinylpyridine) (P4VP) and conjugated molecules of phenol, 2-naphthol and 2-hydroxyanthracene were investigated for non-volatile transistor memory applications. The memory windows of these supramolecular electret devices were significantly enhanced upon increasing the π-conjugation size of the molecule. A high ON/OFF current ratio of more than 10(7) over 10(4) s was achieved on the supramolecule based memory devices.

The combination of the prodrugs perforin-CEBPD and perforin-granzyme B efficiently enhances the activation of caspase signaling and kills prostate cancer.

The survival of prostate cancer (PrCa) patients is associated with the transition to hormone-independent tumor growth and metastasis. Clinically, the dysregulation of androgen action has been associated with the formation of PrCa and the outcome of androgen deprivation therapy in PrCa. CCAAT/enhancer binding protein delta (CEBPD) is a transcription factor that has been reported to act as an oncogene or tumor suppressor, depending on the extra- and intracellular environments following tumorigenesis. We found that androgen can activate CEBPD transcription by direct binding of the androgen receptor (AR) to the CEBPD promoter region. Increases of suppressor of zeste 12 (SUZ12) and enhancer of zeste homolog 2 (EZH2) attenuated the androgen-induced transcription of CEBPD. Importantly, the increases in E2F1, SUZ12 and EZH2 as well as the inactivation of CEBPD were associated with the clinicopathological variables and survival of PrCa patients. We revealed that caspase 8 (CASP8), an apoptotic initiator, is responsive to CEBPD induction. Reporter and in vivo DNA-binding assays revealed that CEBPD directly binds to and activates CASP8 reporter activity. A prodrug system was developed for therapeutic application in AR-independent or androgen-insensitive PrCa to avoid the epigenetic effects on the suppression of CEBPD expression. Our results showed that the combination of a perforin (PF)-CEBPD prodrug (which increases the level of procaspase-8) and a PF-granzyme B prodrug (which activates CASP8 and caspase 3 (CASP3)) showed an additive effect in triggering the apoptotic pathway and enhancing apoptosis in PrCa cells.

Whole-body vibration for functional constipation: a single-centre, single-blinded, randomized controlled trial.

AIM: The aim of this trial was to determine whether whole-body vibration (WBV) induced via a noninvasive oscillation platform could improve symptoms and health-related quality of life (HRQOL) in patients with chronic functional constipation. METHOD: A single-blinded, randomized controlled trial was performed in a single hospital in Taiwan. Patients diagnosed with chronic functional constipation, as per the Rome III diagnostic criteria, were included and randomized to either the WBV treatment or no treatment (control) group. The treatment group received six 15-min sessions of WBV therapy over a 2-week period. Patients received vibrations of 2 mm in amplitude at a frequency of 12 Hz. The primary outcome was whether constipation symptoms improved, assessed by the constipation severity instrument (CSI) and the secondary outcome measure was whether there was an improvement in HRQOL. RESULTS: Whole-body vibration therapy over a 2-week period in patients with chronic functional constipation (n = 14) significantly reduced the total CSI and obstructive defaecation subscale scores compared with control (n = 13). However, WBV did not improve the pain and chronic inertia subscale scores of the CSI or HRQOL. CONCLUSION: These findings suggest that low-intensity WBV induced via a noninvasive oscillation platform may be an effective therapy for reducing symptom severity in patients with chronic functional constipation.

Effects of a preoperative simplified home rehabilitation education program on length of stay of total knee arthroplasty patients.

UNLABELLED: In patients with severe knee osteoarthritis (OA), total knee arthroplasty (TKA) is performed for both symptom relief and to achieve better function in daily life. Implementation of efficient TKA rehabilitation programs with shorter length of stay (LOS) and reduced medical expenditures is an important issue in clinical practice. However, the effectiveness of preoperative rehabilitation programs is still under debate. Most preoperative rehabilitation programs last many weeks and may be more expensive than TKA. The purpose of this study was to investigate the effects of a simplified, easy-to-learn, and less time-consuming preoperative rehabilitation education program on TKA patients. PATIENTS AND METHODS: In this randomized controlled study, we allocated all the patients into study and control group according to chart number. The study group, which comprised 126 patients, participated in a 40-min preoperative home rehabilitation education program 4 weeks prior to TKA. One hundred seventeen patients in the control group did not participate in this preoperative program. RESULTS: The study group required a shorter hospital LOS (mean: 7.12 days; P=0.027) and had less hospitalization-related medical expenditures (mean: 123726 New Taiwan dollars [NTD], equivalent to 4266.4 United States dollars [USD] or 3022.1 [Euros]), (P=0.001) than the control group. However, the study group showed no significant improvement in function when compared to the control group. DISCUSSION: Our study demonstrates that a simplified preoperative rehabilitation program can reduce LOS and increase cost savings. This program was recommended as a routine protocol for OA patients before admission for TKA.

Hepatic venous congestion after living donor liver transplantation: quantitative assessment of liver stiffness using shear wave elastography--a case report.

We report a 49-year-old right lobe liver transplant recipient, who developed a significant anastomotic stenosis of the right hepatic vein shortly thereafter. Shear wave elastography (SWE) was applied to investigate liver stiffness quantitatively. It showed increased stiffness in the anterior compared with the posterior segment of right lobe graft. The stenotic right hepatic venous anastomosis was then managed by angioplasty with stent placement. SWE after angioplasty showed a gradual decrease in stiffness of the anterior segment, which was almost equal to the posterior segment at 2 weeks thereafter. Our experience suggested that SWE may be a noninvasive tool to assess alterations in liver stiffness secondary to hepatic venous congestion after liver transplantation.

Early postoperative spectral Doppler parameters of renal transplants: the effect of donor and recipient factors.

BACKGROUND: The objective of this study was to explore the donor and recipient factors related to the spectral Doppler parameters of the transplant kidney in the early posttransplantation period. METHODS: This retrospective study included 76 patients who underwent renal transplantation assessed using Doppler ultrasonography (US) on the first postoperative day. We compared spectral Doppler parameters (peak systolic velocity [PSV] and resistive index [RI]) of the segmental artery of the transplant kidney according to the type of renal transplant, level of serum creatinine (SCr) of donor prior to organ donation, and donor/recipient age. RESULTS: RI was significantly higher in deceased-donor kidney transplantation (DDKT) as compared with living-donor kidney transplantation (LDKT; 0.73 ± 0.10 vs 0.66 ± 0.11; P = .007). In the DDKT recipients, multivariate analysis showed donor SCr was the only factor affecting PSV (P = .023), whereas recipient age was the only factor affecting RI (P = .035). In the LDKT recipients, multivariate analysis showed recipient age was the only factor affecting both PSV (P = .009) and RI (P = .018). CONCLUSION: Spectral Doppler parameters in the early posttransplantation period are related to the type of renal transplant, donor renal function, and recipient age. These factors should be taken into consideration when interpreting the results of spectral Doppler US.

Investigation of long-term reproducibility of intrinsic connectivity network mapping: a resting-state fMRI study.

BACKGROUND AND PURPOSE: Connectivity mapping based on resting-state fMRI is rapidly developing, and this methodology has great potential for clinical applications. However, before resting-state fMRI can be applied for diagnosis, prognosis, and monitoring treatment for an individual patient with neurologic or psychiatric diseases, it is essential to assess its long-term reproducibility and between-subject variations among healthy individuals. The purpose of the study was to quantify the long-term test-retest reproducibility of ICN measures derived from resting-state fMRI and to assess the between-subject variation of ICN measures across the whole brain. MATERIALS AND METHODS: Longitudinal resting-state fMRI data of 6 healthy volunteers were acquired from 9 scan sessions during >1 year. The within-subject reproducibility and between-subject variation of ICN measures, across the whole brain and major nodes of the DMN, were quantified with the ICC and COV. RESULTS: Our data show that the long-term test-retest reproducibility of ICN measures is outstanding, with >70% of the connectivity networks showing an ICC > 0.60. The COV across 6 healthy volunteers in this sample was >0.2, suggesting significant between-subject variation. CONCLUSIONS: Our data indicate that resting-state ICN measures (eg, the correlation coefficients between fMRI signal-intensity profiles from 2 different brain regions) are potentially suitable as biomarkers for monitoring disease progression and treatment effects in clinical trials and individual patients. Because between-subject variation is significant, it may be difficult to use quantitative ICN measures in their current state as a diagnostic tool.

Serum alpha-fetoprotein response can predict prognosis in hepatocellular carcinoma patients undergoing radiofrequency ablation therapy.

AIMS: To evaluate the clinical inference of serum alpha-fetoprotein (AFP) response in hepatocellular carcinoma (HCC) patients undergoing percutaneous radiofrequency ablation (RFA). MATERIALS AND METHODS: Three hundred and thirteen previously untreated HCC patients were enrolled in the study. The optimal AFP response was defined as >20% decrease from baseline after 1 month of RFA for those with a baseline AFP level of ≥100 ng/ml. The impact of AFP response on prognosis was analysed and prognostic factors were assessed. RESULTS: After a median follow-up of 26.7 ± 19.1 months, 49 patients died and 264 patients were alive. The cumulative 5 year survival rates were 75.3 and 57.4% in patients with an initial AFP of <100 ng/ml and ≥100 ng/ml, respectively (p = 0.003). In the 58 patients with a baseline AFP of ≥100 ng/ml and initial completed tumour necrosis after RFA, the cumulative 5 year survival rates were 62.4 and 25.7% in optimal and non-optimal AFP responders, respectively (p = 0.001). By multivariate analysis, the prothrombin time international normalized ratio >1.1 (p = 0.009), non-optimal AFP response (p = 0.023), and creatinine >1.5 mg/dl (p = 0.021) were independent risk factors predictive of poor overall survival. Besides, the cumulative 5 year recurrence rates were 83.4 and 100% in optimal and non-optimal AFP responders, respectively (p < 0.001). Multivariate analysis demonstrated platelet count ≤10(5)/mm(3) (p = 0.048), tumour size >2 cm (p = 0.027), and non-optimal AFP response (p < 0.001) were independent risk factors associated with tumour recurrence after RFA. CONCLUSIONS: Serum AFP response may be a useful marker for predicting prognosis in HCC patients undergoing RFA.

Contribution of glucocerebrosidase mutation in a large cohort of sporadic Parkinson's disease in Taiwan.

BACKGROUND AND PURPOSE: The association between glucocerebrosidase (GBA) mutations and Parkinson's disease (PD) is attracting increased attention worldwide. In patients of Chinese ethnicity, other than the common L444P mutation, a few mutations have been reported. However, the contribution of GBA to PD can be answered only by a thorough investigation of its mutations in a unique large population. METHODS: We enrolled 1747 participants: 967 PD patients and 780 healthy individuals. We screened entire GBA coding regions and exon-intron boundaries in 30 randomly chosen PD patients, followed by testing five variants (L444P, D409H, R120W, L174P, and Q497R) in all participants. The G2385R and R1628P in LRRK2 had been previously studied in almost all participants. RESULTS: In total, 36 patients (3.72%) carried a heterozygous mutant GBA allele (27 L444P, 7 RecNciI, and 2 D409H). Only two controls (0.26%) carried heterozygous GBA mutation (1 L444P and 1 RecNciI). In PD group, the mean age at onset in carriers was younger than in non-carriers. The difference in percentage of mutation frequencies between patients and controls was highly significant for the L444P mutation (P < 0.0001). One L444P carrier was also associated with LRRK2 G2385R variant, but no atypical Parkinsonism was observed. CONCLUSIONS: The present study ascertains that L444P mutation in GBA gene may contribute to an earlier onset of development of PD in Han/Chinese population. Following LRRK2 variants, GBA is the second most frequent mutations indicated for sporadic PD development in the Han/Chinese population. These GBA carriers are associated with an earlier onset of Parkinsonism.

Increased programmed death-ligand-1 expression in human gastric epithelial cells in Helicobacter pylori infection.

B7-H1 [programmed death-ligand-1 (PD-L1)] is a B7-family member that binds to programmed death-1 (PD-1). Recently, deficiency of PD-L1 has been demonstrated to result in accelerated gastric epithelial cell damage in gastritis, and PD-L1 is suggested to play a critical role in regulating T cell homeostasis. Here, we aimed to gain more insight into gastric PD-L1 expression, regulation and function during Helicobacter pylori infection. PD-L1 expression in human gastric epithelial cells was analysed using Western blotting, quantitative polymerase chain reaction and fluorescence activated cell sorter analysis. Furthermore, co-culture experiments of human gastric epithelial cells with primary human T cells or Jurkat T cells were conducted. PD-L1 expression in primary human gastric epithelial cells was strongly enhanced by H. pylori infection and activated T cells, and augmented markedly by further stimulation with interferon-γ or tumour necrosis factor-α. Moreover, PD-L1 expression in gastric epithelial cells significantly induced apoptosis of T cells. Our results indicate that a novel bidirectional interaction between human gastric epithelial cells and lymphocytes modulates PD-L1 expression in human gastric epithelial cells, contributing to the unique immunological properties of the stomach.

Analysis of the UCHL1 genetic variant in Parkinson's disease among Chinese.

The inverse association of the functional ubiquitin carboxy-terminal hydrolase L1 (UCHL1) S18Y variant with Parkinson's disease (PD) among Caucasian populations has been debated. We conducted a large-scale analysis to investigate the age-of-onset effect of the UCHL1 variant in PD among ethnic Chinese. Individual data sets from 5 centers comprising a total of 4088 study subjects were analyzed. In the univariate analysis, only data from 1 center showed a trend towards a protective effect among young subjects. However, in the combined analysis, no significant association between the UCHL1 variant and PD was detected (A allele frequency 0.531 vs. 0.528, p=0.87, OR 1.01, 95% CI 0.92-1.1). Among subjects less than 60 years old, the OR is 0.99 (95% CI 0.84-1.16, p=0.88). A multivariate logistic regression analysis showed that family history, UCHL1 variant and the interaction of UCHL1 variant and age at onset (p=0.816) were not significantly associated with PD.

A longitudinal study of Taiwanese sialidosis type 1: an insight into the concept of cherry-red spot myoclonus syndrome.

BACKGROUND AND PURPOSE: Sialidosis type 1 (ST-1) is a neurodegenerative disorder with limited long-term follow-up report. This study is to document the chronological profile of ST-1. METHODS: We perform serial analysis of 17 Taiwanese patients with ST-1 focusing on evolution of clinical features, electrophysiological findings, genetic studies, and neuroimage examinations. RESULTS: All patients had a mutation at 554A-->G in exon 3 of the NEU1 gene causing Ser182Gly substitution. Fifteen patients were homozygous. Two patients were heterozygous with novel mutations, 956C-->T causing Ala319Val in one and 163C-->T causing Gln55stop codon in the other. The neuraminidase activity was markedly decreased in all 11 available patients. Only three patients (17.6%) manifested the macular cherry-red spot. The majority of patients (82.3%) developed full-blown manifestation of myoclonus, ataxia, and seizures within 5 years. Abnormal somatosensory evoked potentials with giant cortical waves were found in all patients. Prolonged P100 peak latency of the visual evoked potentials (VEPs) were found in 16 patients (94.1%) in the early stage even without visual symptoms. CONCLUSION: ST-1 in Taiwanese population illustrates distinct characteristics of phenotype with infrequent cherry-red spot. We suggest to screen the NEU1 mutations in patients presenting action myoclonus with abnormal VEPs, even without macular cherry-red spots.

Dynamic contrast-enhanced and T2-weighted magnetic resonance imaging study of the correlation between tumour angiogenesis and growth kinetics.

Accumulating evidence indicates that tumour growth is angiogenesis-dependent. Non-invasive assessment of the relationship between tumour growth and associated angiogenesis is essential for diagnosis and for therapeutic interventions. We utilized a combination of high-resolution T2-weighted and dynamic contrast-enhanced magnetic resonance imaging to investigate the dynamics of angiogenesis during tumour growth in a mouse tumour model expressing Epstein-Barr virus-encoded latent membrane protein 1 isolated from a nasopharyngeal carcinoma in Taiwan. Serial imaging acquisitions were performed starting on the third day after subcutaneous implantation of tumours, through day 28. We observed a progressive increase in tumour volume until day 14, followed by rapid and exponential growth. The volume transfer constant, K(trans), also increased significantly on day 14, and then gradually decreased, suggesting that the angiogenic switching occurs prior to significant tumour growth. At the initial stage, the K(trans) values were significantly higher in the tumour peripheral region than in the tumour core, but, during tumour growth, the K(trans) values in the region between the tumour periphery and core gradually increased, becoming larger than those of the periphery. These results demonstrate that the ability to perform repeated measurements assessing the correlation between tumour growth kinetics and tumour angiogenesis makes it possible to determine the critical time of angiogenic switching prior to rapid tumour growth, as well as suggesting the timing of therapy.

The remarkable influence of M2delta to thienyl pi conjugation in oligothiophenes incorporating MM quadruple bonds.

Oligothiophenes incorporating MM quadruple bonds have been prepared from the reactions between Mo(2)(TiPB)(4) (TiPB = 2,4,6-triisopropyl benzoate) and 3',4'-dihexyl-2,2'-:5',2''-terthiophene-5,5''-dicarboxylic acid. The oligomers of empirical formula Mo(2)(TiPB)(2)(O(2)C(Th)-C(4)(n-hexyl)(2)S-(Th)CO(2)) are soluble in THF and form thin films with spin-coating (Th = thiophene). The reactions between Mo(2)(TiPB)(4) and 2-thienylcarboxylic acid (Th-H), 2,2'-bithiophene-5-carboxylic acid (BTh-H), and (2,2':5',2''-terthiophene)-5-carboxylic acid (TTh-H) yield compounds of formula trans-Mo(2)(TiPB)(2)L(2), where L = Th, BTh, and TTh (the corresponding thienylcarboxylate), and these compounds are considered as models for the aforementioned oligomers. In all cases, the thienyl groups are substituted or coupled at the 2,5 positions. Based on the x-ray analysis, the molecular structure of trans-Mo(2)(TiPB)(2)(BTh)(2) reveals an extended Lpi-M(2)delta-Lpi conjugation. Calculations of the electronic structures on model compounds, in which the TiPB are substituted by formate ligands, reveal that the HOMO is mainly attributed to the M(2)delta orbital, which is stabilized by back-bonding to one of the thienylcarboxylate pi* combinations, and the LUMO is an in-phase combination of the thienylcarboxylate pi* orbitals. The compounds and the oligomers are intensely colored due to M(2)delta-thienyl carboxylate pi* charge transfer transitions that fall in the visible region of the spectrum. For the molybdenum complexes and their oligomers, the photophysical properties have been studied by steady-state absorption spectroscopy and emission spectroscopy, together with time-resolved emission and transient absorption for the determination of relaxation dynamics. Remarkably, THF solutions the molybdenum complexes show room-temperature dual emission, fluorescence and phosphorescence, originating mainly from (1)MLCT and (3)MM(deltadelta*) states, respectively. With increasing number of thienyl rings from 1 to 3, the observed lifetimes of the (1)MLCT state increase from 4 to 12 ps, while the phosphorescence lifetimes are approximately 80 micros. The oligomers show similar photophysical properties as the corresponding monomers in THF but have notably longer-lived triplet states, approximately 200 micros in thin films. These results, when compared with metallated oligothiophenes of the later transition elements, reveal that M(2)delta-thienyl pi conjugation leads to a very small energy gap between the (1)MLCT and (3)MLCT states of <0.6 eV.

Evaluation of cortical perfusion in renal transplants: application of quantified power Doppler ultrasonography.

Perfusion of renal transplants may be altered by various pathological conditions. This study assessed cortical perfusion of renal transplants during acute rejection episodes using power Doppler quantification. Forty-eight renal transplant patients with clinical indications for biopsy were included in this study. Power Doppler ultrasonography (US) of these renal transplants was performed prior to biopsy. Power Doppler image intensity in the proximal outer cortex of renal transplants was quantified by image analysis software. The results of power Doppler quantification were compared with the clinical data and histological findings. Biopsies were classified into three groups based on Banff diagnostic categories: group 1 (no acute rejection; 26 patients), group 2 (acute cell-mediated rejection alone; 12 patients), and group 3 (acute antibody-mediated rejection with/or without acute cell-mediated rejection; 10 patients). The power Doppler intensity of the outer renal cortex was 1.98 +/- 1.50 dB for group 1, 1.38 +/- 0.86 dB for group 2, and 0.81 +/- 0.66 dB for group 3. Statistically, there was a significant difference between group 1 and group 3 (1.98 vs 0.81 dB, P = .01) but not between group 1 and group 2 (1.98 vs 1.38 dB, P = .34). In conclusion, the status of cortical perfusion of renal transplants can be determined noninvasively by quantified power Doppler US. Accordingly, acute antibody-mediated rejection is associated with significantly decreased cortical perfusion, which, we propose, is due to this distinct pathological process.