Combined Orbital and Cranial Vessel Wall Magnetic Resonance Imaging for the Assessment of Disease Activity in Giant Cell Arteritis

OBJECTIVE

Acute visual impairment is the most feared complication of giant cell arteritis (GCA) but is challenging to predict. Magnetic resonance imaging (MRI) evaluates orbital pathology not visualized by an ophthalmologic examination. This study combined orbital and cranial vessel wall MRI to assess both orbital and cranial disease activity in patients with GCA, including patients without visual symptoms.

METHODS

Patients with suspected active GCA who underwent orbital and cranial vessel wall MRI were included. In 14 patients, repeat imaging over 12 months assessed sensitivity to change. Clinical diagnosis of ocular or nonocular GCA was determined by a rheumatologist and/or ophthalmologist. A radiologist masked to clinical data scored MRI enhancement of structures.

RESULTS

Sixty-four patients with suspected GCA were included: 25 (39%) received a clinical diagnosis of GCA, including 12 (19%) with ocular GCA. Orbital MRI enhancement was observed in 83% of patients with ocular GCA, 38% of patients with nonocular GCA, and 5% of patients with non-GCA. MRI had strong diagnostic performance for both any GCA and ocular GCA. Combining MRI with a funduscopic examination reached 100% sensitivity for ocular GCA. MRI enhancement significantly decreased after treatment (P < 0.01).

CONCLUSION

In GCA, MRI is a sensitive tool that comprehensively evaluates multiple cranial structures, including the orbits, which are the most concerning site of pathology. Orbital enhancement in patients without visual symptoms suggests that MRI may detect at-risk subclinical ocular disease in GCA. MRI scores decreased following treatment, suggesting scores reflect inflammation. Future studies are needed to determine if MRI can identify patients at low risk for blindness who may receive less glucocorticoid therapy.

Patient-Reported Sinonasal Symptoms and Risk of Relapse in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

OBJECTIVE

Relapses are frequent and difficult to predict in antineutrophil cytoplasmic antibody-associated vasculitis (AAV), resulting in long-term use of immunosuppression. Although sinonasal disease is associated with relapse of AAV, detailed characterization of sinonasal symptoms is lacking. Using a patient-reported outcome, the 22-item SinoNasal Outcome Test (SNOT-22), we investigated the relationship between sinonasal symptoms and disease activity in AAV.

METHODS

This was a prospective, longitudinal study of individual with AAV and healthy individuals. Relapse was defined as a Birmingham Vasculitis Activity Score for Wegner's Granulomatosis score >0. Higher SNOT-22 scores indicate worse symptoms. Generalized estimating equation and Cox proportional hazard models evaluated the association between SNOT-22 and relapse.

RESULTS

There were 773 visits (106 active disease visits) from 168 patients with AAV and 51 controls. Median SNOT-22 at remission was higher in AAV versus controls (20 vs 5; P < 0.001) and higher during active disease versus remission (P < 0.001). In all AAV, and particularly within granulomatosis with polyangiitis, higher SNOT-22 scores were observed months to years before relapse and were associated with increased risk of relapse (hazard ratio 2.7, 95% confidence interval 1.2-6.2; P = 0.02). Similar findings were seen when examining patients with versus without sinonasal disease and after removing relapses limited to the ear, nose, and throat.

CONCLUSION

A patient-reported outcome measure of sinonasal disease, the SNOT-22, not only changes with disease activity in AAV, but also is associated with a higher risk of relapse within two years. These findings support the possibility that the SNOT-22 score may enhance prediction of relapse and that persistent sinonasal disease may be important in the pathophysiology of relapse.

The molecular basis of spinocerebellar ataxia type 48 caused by a de novo mutation in the ubiquitin ligase CHIP

The spinocerebellar ataxias (SCAs) are a class of incurable diseases characterized by degeneration of the cerebellum that results in movement disorder. Recently, a new heritable form of SCA, spinocerebellar ataxia type 48 (SCA48), was attributed to dominant mutations in STIP1 homology and U box-containing 1 (STUB1); however, little is known about how these mutations cause SCA48. STUB1 encodes for the protein C terminus of Hsc70 interacting protein (CHIP), an E3 ubiquitin ligase. CHIP is known to regulate proteostasis by recruiting chaperones via a N-terminal tetratricopeptide repeat domain and recruiting E2 ubiquitin-conjugating enzymes via a C-terminal U-box domain. These interactions allow CHIP to mediate the ubiquitination of chaperone-bound, misfolded proteins to promote their degradation via the proteasome. Here we have identified a novel, de novo mutation in STUB1 in a patient with SCA48 encoding for an A52G point mutation in the tetratricopeptide repeat domain of CHIP. Utilizing an array of biophysical, biochemical, and cellular assays, we demonstrate that the CHIPA52G point mutant retains E3-ligase activity but has decreased affinity for chaperones. We further show that this mutant decreases cellular fitness in response to certain cellular stressors and induces neurodegeneration in a transgenic Caenorhabditis elegans model of SCA48. Together, our data identify the A52G mutant as a cause of SCA48 and provide molecular insight into how mutations in STUB1 cause SCA48.

Dynamic Changes in the Nasal Microbiome Associated With Disease Activity in Patients With Granulomatosis With Polyangiitis

OBJECTIVE

Little is known about temporal changes in nasal bacteria in granulomatosis with polyangiitis (GPA). This study was undertaken to examine longitudinal changes in the nasal microbiome in association with relapse in GPA patients.

METHODS

Bacterial 16S ribosomal RNA gene sequencing was performed on nasal swabs from 19 patients with GPA who were followed up longitudinally for a total of 78 visits, including 9 patients who experienced a relapse and 10 patients who remained in remission. Relative abundance of bacteria and ratios between bacteria were examined. Generalized estimating equation models were used to evaluate the association between bacterial composition and 1) disease activity and 2) levels of antineutrophil cytoplasmic antibody (ANCA) with specificity for proteinase 3 (PR3), adjusted for medication.

RESULTS

Corynebacterium and Staphylococcus were the most abundant bacterial genera across all nasal samples. Patients with quiescent disease maintained a stable ratio of Corynebacterium to Staphylococcus across visits. In contrast, in patients who experienced a relapse, a significantly lower ratio was observed at the visit prior to relapse, followed by a higher ratio at the time of relapse (adjusted P < 0.01). Species-level analysis identified an association between a higher abundance of nasal Corynebacterium tuberculostearicum and 1) relapse (adjusted P = 0.04) and 2) higher PR3-ANCA levels (adjusted P = 0.02).

CONCLUSION

In GPA, significant changes occur in the nasal microbiome over time and are associated with disease activity. The occurrence of these changes months prior to the onset of relapse supports a pathogenic role of nasal bacteria in GPA. Our results uphold existing hypotheses implicating Staphylococcus as an instigator of disease and have generated a novel finding involving Corynebacterium as a potential mediator of disease in GPA.

[Multimodality navigation for liver resection of complicated alveolar echinococcosis]

Objective: To investigate the clinical application of multimodality navigation for liver resection in the treatment of complicated alveolar echinococcosis (AE). Methods: From October 2019 to February 2020, the clinical data and perioperative results of patients with AE treated by surgery in our department were retrospectively studied. Hepatic parenchyma disconnection plane and liver resection were navigated and performed with three-dimensional reconstruction and HITACHI real-time multi-image fusion interventional navigation system (RVS). Results: All of six patients were successful performed radical liver resection without mortality. The operation time was (301±106)min and the median blood loss was 200 ml. Two patients needed blood transfusion intraoperative (33.33%). The postoperative hospital stay was (10.8±2.8) day, and the cost of hospitalization was (82 584±995.61) yuan. Clavien-Dindo grade Ⅲ complication occurred in one patient. Conclusions: Multimodality navigation might provide precise intraoperative navigation of the surgical plane and effectively assist liver resection for the treatment of complicated AE.

[Robotic hilar cholangiocarcinoma radical resection compared with laparotomy in prognosis]

Objective: To compare the long term and short term outcomes between robotic and open surgery for hilar cholangiocarcinoma radical resection. Methods: This is a single-center and retrospective case-control study. Patients underwent hilar cholangiocarcinoma radical resection between January 2016 and December 2016 at Department of Hepatobiliary Surgery of the General Hospital of the Chinese People's Liberation Army were included. Safety, effectiveness and long-term prognosis of tumors were evaluated. Patients were divided into robotic hilar cholangiocarcinoma radical surgery group (robotic group, n=16) and open hepatic hilar cholangiocarcinoma radical surgery group (open group, n=31) . All cases were confirmed by pathology histological. Age, gender, histology, resection margin status, extent of surgical resection, disease-free survival (DFS) , and overall survival (OS) were retrospectively collected and analyzed.In the follow-up cohort, the primary outcome was patient death and the secondary outcome was tumor recurrence. Continuous variables were expressed as means and medians and were compared using the Student t test if normally distributed or Wilcoxon-Mann-Whitney test for nonparametric variables. Discrete variables were expressed as frequency and percentages and χ(2) or Fisher exact test, when appropriate, were used for comparisons. Kaplan-Meier curves were used to calculate the probability of survival and comparisons were performed using log-rank test. Results: In this study, compared with the open group, the robotic group had a longer operation time ( (338±71) minutes vs. (256±56) minutes, t=4.251, P=0.001) , but the intraoperative blood loss was less (100 ml vs. 200 ml, Z=121.50, P=0.040) , the gastric tube removal time was earlier (3 days vs. 4 days, Z=136.0, P=0.011) , and the postoperative hospital stay was shorter (9 days vs. 12 days, Z=144.50, P=0.040) , and the difference was statistically significant.There was no significant difference in the blood transfusion rate, R0 resection rate, and tumor size between the two groups.The recurrence rates in the robotic group and open surgery were 53.3% and 67.0%, respectively (χ(2)=1.04, P=0.307) .The median survival time of the robotic group and the open group was 22.0 months and 25.0 months. There was no significant difference in the overall survival rate between the two groups (P>0.05) . Conclusion: Compared with laparotomy, robotic HCC radical resection could have an equivalence or non-inferiority approach with acceptable long-term outcome.

Vitiligo-like depigmentation in oncology patients treated with immunotherapies for nonmelanoma metastatic cancers

Vitiligo-like depigmentation (VLD) is a characteristic cutaneous event described in patients with metastatic malignant melanoma receiving treatment with immune checkpoint inhibitors. We report the onset of VLD in three patients with other cancer types (cholangiocarcinoma, renal cell carcinoma and squamous cell carcinoma) following treatment with immunotherapy (combination pembrolizumab and nivolumab for the first, and pembrolizumab for the other two cancer types). Cases of VLD have not been reported previously in patients treated for any of these cancers, to our knowledge. Pembrolizumab and nivolumab are monoclonal antibodies targeting programmed cell death (PD)-1 receptors, while ipilimumab targets cytotoxic T-lymphocyte antigen-4. Our clinical finding challenges the current understanding of VLD as a malignant melanoma-specific immunotherapy-related adverse event.

Collective Deceleration of Laser-Driven Electron Bunches

Few-fs electron bunches from laser wakefield acceleration (LWFA) can efficiently drive plasma wakefields (PWFs), as shown by their propagation through underdense plasma in two experiments. A strong and density-insensitive deceleration of the bunches has been observed in 2 mm of 10^{18}  cm^{-3} density plasma with 5.1  GV/m average gradient, which is attributed to a self-driven PWF. This observation implies that the physics of PWFs, usually relying on large-scale rf accelerators as drivers, can be studied by tabletop LWFA electron sources.

The chemical class of quinazoline compounds provides a core structure for the design of anticytomegaloviral kinase inhibitors

HCMV is a member of the family Herpesviridae and represents a worldwide distributed pathogen with seropositivity rates in the adult population ranging between 40% and 90%. Notably, HCMV infection is a serious, sometimes life-threatening medical problem for newborns and immunosuppressed individuals, including transplant recipients and patients under antitumoral chemotherapy. Current standard therapy with valganciclovir has the disadvantage of inducing drug-resistant virus mutants and toxicity-related side effects. Our analysis stresses the earlier finding that kinase inhibitors of the quinazoline class exert an antiviral response by targeting the viral protein kinase pUL97 without inducing resistance. Therefore, quinazolines have been used as a core structure to gain insight in the mode of inhibitor-kinase interaction. Here, we demonstrate that (i) the novel quinazolines Vi7392 and Vi7453 are highly active against HCMV laboratory and clinically relevant strains including maribavir- and ganciclovir-resistant variants, (ii) antiviral activity is not cell-type specific and was also detected in a placental explant tissue model using a genetically intact HCMV strain (iii) the viral kinase pUL97 represents a target of the anticytomegaloviral activity of these compounds, (iv) induction of pUL97-conferring drug resistance was not detectable under single-step selection, thus differed from the induction of ganciclovir resistance, and (v) pUL97 drug docking simulations enabled detailed insights into specific drug-target binding properties providing a promising basis for the design of optimized kinase inhibitors. These novel findings may open new prospects for the future medical use of quinazoline drug candidates and the use of drug-target dynamic simulations for rational design of antivirals.

The International Multidisciplinary Consensus Conference on Multimodality Monitoring in Neurocritical Care: a list of recommendations and additional conclusions: a statement for healthcare professionals from the Neurocritical Care Society and the European Society of Intensive Care Medicine

Careful patient monitoring using a variety of techniques including clinical and laboratory evaluation, bedside physiological monitoring with continuous or non-continuous techniques and imaging is fundamental to the care of patients who require neurocritical care. How best to perform and use bedside monitoring is still being elucidated. To create a basic platform for care and a foundation for further research the Neurocritical Care Society in collaboration with the European Society of Intensive Care Medicine, the Society for Critical Care Medicine and the Latin America Brain Injury Consortium organized an international, multidisciplinary consensus conference to develop recommendations about physiologic bedside monitoring. This supplement contains a Consensus Summary Statement with recommendations and individual topic reviews as a background to the recommendations. In this article, we highlight the recommendations and provide additional conclusions as an aid to the reader and to facilitate bedside care.

The International Multidisciplinary Consensus Conference on Multimodality Monitoring in Neurocritical Care: evidentiary tables: a statement for healthcare professionals from the Neurocritical Care Society and the European Society of Intensive Care Medicine

A variety of technologies have been developed to assist decision-making during the management of patients with acute brain injury who require intensive care. A large body of research has been generated describing these various technologies. The Neurocritical Care Society (NCS) in collaboration with the European Society of Intensive Care Medicine (ESICM), the Society for Critical Care Medicine (SCCM), and the Latin America Brain Injury Consortium (LABIC) organized an international, multidisciplinary consensus conference to perform a systematic review of the published literature to help develop evidence-based practice recommendations on bedside physiologic monitoring. This supplement contains a Consensus Summary Statement with recommendations and individual topic reviews on physiologic processes important in the care of acute brain injury. In this article we provide the evidentiary tables for select topics including systemic hemodynamics, intracranial pressure, brain and systemic oxygenation, EEG, brain metabolism, biomarkers, processes of care and monitoring in emerging economies to provide the clinician ready access to evidence that supports recommendations about neuromonitoring.

Consensus summary statement of the International Multidisciplinary Consensus Conference on Multimodality Monitoring in Neurocritical Care: a statement for healthcare professionals from the Neurocritical Care Society and the European Society of Intensive Care Medicine

Neurocritical care depends, in part, on careful patient monitoring but as yet there are little data on what processes are the most important to monitor, how these should be monitored, and whether monitoring these processes is cost-effective and impacts outcome. At the same time, bioinformatics is a rapidly emerging field in critical care but as yet there is little agreement or standardization on what information is important and how it should be displayed and analyzed. The Neurocritical Care Society in collaboration with the European Society of Intensive Care Medicine, the Society for Critical Care Medicine, and the Latin America Brain Injury Consortium organized an international, multidisciplinary consensus conference to begin to address these needs. International experts from neurosurgery, neurocritical care, neurology, critical care, neuroanesthesiology, nursing, pharmacy, and informatics were recruited on the basis of their research, publication record, and expertise. They undertook a systematic literature review to develop recommendations about specific topics on physiologic processes important to the care of patients with disorders that require neurocritical care. This review does not make recommendations about treatment, imaging, and intraoperative monitoring. A multidisciplinary jury, selected for their expertise in clinical investigation and development of practice guidelines, guided this process. The GRADE system was used to develop recommendations based on literature review, discussion, integrating the literature with the participants' collective experience, and critical review by an impartial jury. Emphasis was placed on the principle that recommendations should be based on both data quality and on trade-offs and translation into clinical practice. Strong consideration was given to providing pragmatic guidance and recommendations for bedside neuromonitoring, even in the absence of high quality data.

Consensus summary statement of the International Multidisciplinary Consensus Conference on Multimodality Monitoring in Neurocritical Care : a statement for healthcare professionals from the Neurocritical Care Society and the European Society of Intensive Care Medicine

Neurocritical care depends, in part, on careful patient monitoring but as yet there are little data on what processes are the most important to monitor, how these should be monitored, and whether monitoring these processes is cost-effective and impacts outcome. At the same time, bioinformatics is a rapidly emerging field in critical care but as yet there is little agreement or standardization on what information is important and how it should be displayed and analyzed. The Neurocritical Care Society in collaboration with the European Society of Intensive Care Medicine, the Society for Critical Care Medicine, and the Latin America Brain Injury Consortium organized an international, multidisciplinary consensus conference to begin to address these needs. International experts from neurosurgery, neurocritical care, neurology, critical care, neuroanesthesiology, nursing, pharmacy, and informatics were recruited on the basis of their research, publication record, and expertise. They undertook a systematic literature review to develop recommendations about specific topics on physiologic processes important to the care of patients with disorders that require neurocritical care. This review does not make recommendations about treatment, imaging, and intraoperative monitoring. A multidisciplinary jury, selected for their expertise in clinical investigation and development of practice guidelines, guided this process. The GRADE system was used to develop recommendations based on literature review, discussion, integrating the literature with the participants' collective experience, and critical review by an impartial jury. Emphasis was placed on the principle that recommendations should be based on both data quality and on trade-offs and translation into clinical practice. Strong consideration was given to providing pragmatic guidance and recommendations for bedside neuromonitoring, even in the absence of high quality data.

Impaired cerebral autoregulation is associated with vasospasm and delayed cerebral ischemia in subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Cerebral autoregulation may be impaired in the early days after subarachnoid hemorrhage (SAH). The purpose of this study was to examine the relationship between cerebral autoregulation and angiographic vasospasm (aVSP) and radiographic delayed cerebral ischemia (DCI) in patients with SAH.

METHODS

Sixty-eight patients (54±13 years) with a diagnosis of nontraumatic SAH were studied. Dynamic cerebral autoregulation was assessed using transfer function analysis (phase and gain) of the spontaneous blood pressure and blood flow velocity oscillations on days 2 to 4 post-SAH. aVSP was diagnosed using a 4-vessel conventional angiogram. DCI was diagnosed from CT. Decision tree models were used to identify optimal cut-off points for clinical and physiological predictors of aVSP and DCI. Multivariate logistic regression models were used to develop and validate a risk scoring tool for each outcome.

RESULTS

Sixty-two percent of patients developed aVSP, and 19% developed DCI. Patients with aVSP had higher transfer function gain (1.06±0.33 versus 0.89±0.30; P=0.04) and patients with DCI had lower transfer function phase (17.5±39.6 versus 38.3±18.2; P=0.03) compared with those who did not develop either. Multivariable scoring tools using transfer function gain>0.98 and phase<12.5 were strongly predictive of aVSP (92% positive predictive value; 77% negative predictive value; area under the receiver operating characteristic curve, 0.92) and DCI (80% positive predictive value; 91% negative predictive value; area under the curve, 0.94), respectively.

CONCLUSIONS

Dynamic cerebral autoregulation is impaired in the early days after SAH. Including autoregulation as part of the initial clinical and radiographic assessment may enhance our ability to identify patients at a high risk for developing secondary complications after SAH.

Proteomic Protease Substrate Profiling of tPA Treatment in Acute Ischemic Stroke Patients: A Step Toward Individualizing Thrombolytic Therapy at the Bedside

Tissue plasminogen activator (tPA) is the only FDA-approved medical therapy for acute ischemic stroke. But as a serine peptidase, intravenous tPA can affect the expression of other proteases that may be implicated in blood-brain barrier breakdown. Such parallel cascades of cell signaling may be involved in intracranial hemorrhage, the major side effect of tPA. Here, we describe an initial attempt in proteomic substrate profiling, i.e., degradomics in human plasma within the context of acute stroke. Plasma from acute stroke patients were analyzed pre- and post-intravenous tPA using tandem mass spectrometry and protein array profiling to identify substrates and proteases of interest. In non-tPA-treated stroke plasma, degradomic patterns indicated a rapid induction of protease activity within 3 h of stroke onset that mostly stabilized by 24 h. But in tPA-treated patients, pre- and post-tPA samples from the same patient demonstrated distinct degradomic patterns that persisted even up to 3-5 days after stroke onset. Matching control patients without strokes had little change in degradomic profiles over time. Our findings demonstrate that tPA treatment changes the plasma degradomic profiles in acute stroke patients. These composite proteolytic profiles may provide a glimpse of the pleiotropic effects of tPA on cellular signaling cascades at the bedside. This study supports the feasibility of performing pharmaco-proteomics at the bedside, which may ultimately allow us to dissect mechanisms of thrombolysis-related therapeutic efficacy in stroke.

Accidental overheating of a newborn under an infant radiant warmer: a lesson for future use

A fully functional radiant warmer induced rapid and continuous increases in regional skin temperatures, heart rate, mean arterial blood pressure and respiratory rate in a newborn patient without corrective action. We report this case of passive overheating to create awareness of the risks associated with regulating radiant heat output based upon a single servo-controlled temperature.

Optimization of microencapsulation parameters: Semipermeable microcapsules as a bioartificial pancreas

An improved membrane has been developed for the microencapsulation of islets of Langerhans which protects these cells from the immune system. These requirements were accomplished through the optimization of important microencapsulation parameters and through the improved biocompatibility of a new alginate-poly-l-lysine (PLL)-alginate capsule membrane. Spherical and smooth microcapsules could be formed by utilizing a purer sodium alginate and by keeping the viscosity of the sodium alginate solution above 30 cps. The strength of the capsule membrane was enhanced by increasing the alginate-PLL reaction time as well as the PLL concentration. The permeability of the membrane [4 mum thick, 93% (w/w) water] was a function of the viscosity average molecular weight (Mv) of the PLL (Mv = 4000-4 x 10(5)) used in the encapsulation procedure. Microcapsules prepared with PLL with Mv = 1.7 x 10(4) were the least permeable, being impermeable to normal serum immunoglobulin, albumin, and haemoglobin. The microencapsulation procedure, by protecting transplanted tissue from the components of the immune system, has great clinical potential as a new form of treatment for diseases such as diabetes and liver disease.

Discrimination of ischemic and hemorrhagic strokes using a multiplexed, mass spectrometry-based assay for serum apolipoproteins coupled to multi-marker ROC algorithm

PURPOSE

Typically, apolipoproteins are individually measured in blood by immunoassay. In this report, we describe the development of a multiplexed selected reaction monitoring (SRM) based assay for a panel of apolipoproteins and its application to a clinical cohort of samples derived from acute stroke patients.

EXPERIMENTAL DESIGN

An SRM assay for a panel of nine apolipoproteins was developed on a triple quadrupole mass spectrometer. Quantitative data for each apolipoprotein were analyzed to determine expression ratio and receiver operating characteristic (ROC) values for ischemic versus hemorrhagic stroke.

RESULTS

The optimized SRM assay was used to interrogate a small cohort of well-characterized plasma samples obtained from patients with acute ischemic and hemorrhagic strokes. The ROC analyses demonstrated good classification power for several single apolipoproteins, most notably apoC-III and apoC-I. When a novel multi-marker ROC algorithm was applied, the ischemic versus hemorrhagic groups were best differentiated by a combination of apoC-III and apoA-I with an area under the curve (AUC) value of 0.92.

CONCLUSIONS AND CLINICAL RELEVANCE

This proof-of-concept study provides interesting and provocative data for distinguishing ischemic versus hemorrhage within first week of symptom onset. However, the observations are based on one cohort of patient samples and further confirmation will be required.

Oral maribavir for treatment of refractory or resistant cytomegalovirus infections in transplant recipients

BACKGROUND

Despite advances in cytomegalovirus (CMV) prophylaxis and therapy, some transplant recipients still develop refractory CMV infections. Maribavir (MBV), an investigational benzimidazole antiviral agent, acts by a mechanism different from that of existing anti-CMV drugs. Previous Phase I and II studies have demonstrated a favorable safety profile for MBV, but its utility in treatment of complex CMV syndromes is unknown.

METHODS

Between June and December 2008, MBV was released for use under individual emergency investigational new drug applications requested by treating physicians and approved by the US Food and Drug Administration and local institutional review boards. Six patients (5 solid organ transplant recipients and 1 hematopoietic stem cell transplant recipient) who had failed to respond to other therapies and/or had known ganciclovir-resistant CMV were treated with MBV at a starting oral dose of 400 mg twice daily.

RESULTS

Patients were treated for a median of 207 days (range, 15-376). Four of 6 patients had no detectable CMV DNAemia within 6 weeks of starting MBV therapy. One patient, who had an initial viral load of 1.8 million copies/mL, developed MBV resistance mutations. One patient, who had low serum levels of MBV, had persistent CMV DNAemia and viruria without developing genotypic or phenotypic resistance to MBV. One patient cleared CMV DNAemia, but died of pneumonia and multiorgan failure. No significant adverse effects attributable to MBV were observed.

CONCLUSIONS

MBV deserves further systematic evaluation as treatment for CMV infection that is resistant and/or refractory to standard therapies, but its optimal dose, duration of therapy, and use in combinations versus as a single agent have yet to be determined.

Is staging beneficial for Fowler-Stephens orchiopexy? A systematic review

PURPOSE

Fowler and Stephens showed that by dividing the spermatic vessels a high intra-abdominal testis could be placed in the scrotum. Testicular atrophy is a potential complication of this technique. We conducted a systematic review to determine whether single or 2-stage Fowler-Stephens orchiopexy results in better testicular viability.

MATERIALS AND METHODS

We searched electronic databases, clinical trial registries and gray literature. We included reports describing boys younger than 18 years with a primary outcome of "testicular viability and position." We performed a meta-analysis using random effects models. Heterogeneity was assessed using forest plot and I(2) statistic.

RESULTS

We identified 1,807 citations and included 61 articles. Single stage Fowler-Stephens orchiopexy was discussed in 9 articles, a 2-stage procedure in 36 and both approaches in 16. There were no randomized controlled trials, and most studies were cohort or case series. The pooled estimate of success rates was 80% for single stage Fowler-Stephens orchiopexy (95% CI 75 to 86) and 85% for 2-stage Fowler-Stephens orchiopexy (95% CI 81 to 90). The pooled odds ratio of single stage vs 2-stage Fowler-Stephens orchiopexy was 2.0 (95% CI 1.1 to 3.9) favoring the 2-stage procedure. There was no difference in the success rate between laparoscopic and open techniques in either single or 2-stage Fowler-Stephens orchiopexy. There was no evidence of asymmetry on the funnel plot. There were no complications reported with single stage, while ileus, hematoma and infection were the most common complications with 2-stage Fowler-Stephens orchiopexy.

CONCLUSIONS

Both techniques have a fairly high success rate but 2-stage Fowler-Stephens orchiopexy appears to carry a higher rate of success than the single stage approach (85% vs 80%, OR 2 in favor of 2-stage). Laparoscopic and open techniques had the same success rate. However, the level of evidence of the studies was low, and a study of a more robust design, such as a randomized controlled trial, should be performed.

Patient and allograft survival of Indo Asian and East Asian dialysis patients treated in Canada

Kidney failure is relatively common among Canadians of Asian origin. However, little is known about the health outcomes after initiation of renal replacement therapy in this population. Our study evaluates differences in the likelihood of renal transplantation and graft loss among Asian and white patients. We studied 21 523 adults of East Asian, Indo Asian or white ethnicity who had initiated dialysis in Canada from 1990-2000. Subjects were followed until death, loss to follow-up or end of study (2004). The proportion of the eligible subjects who were East Asian, Indo Asian, or white was 6, 3, and 91%, respectively. Compared to white patients, East Asian and Indo Asian patients were significantly less likely to receive a renal transplant after adjusting for potential confounding factors. This disparity is greater for transplants from living donors as compared to those from deceased donors. The adjusted death censored graft loss in transplant recipients was not significantly different between ethnic groups. The adjusted risk of death following transplantation, however, was significantly lower in Indo Asian than in white patients. Our findings show that in a Canadian population, patients of East Asian or Indo Asian origin had lower rates of renal transplantation than white patients, especially for living donor transplantation. These findings warrant further study, especially given the good graft outcomes in these individuals.

Expression profiling of the Arabidopsis annexin gene family during germination, de-etiolation and abiotic stress

Annexins are a multigene family in most plant species and are suggested to play a role in a wide variety of essential cellular processes. In Arabidopsis thaliana there are eight different annexins (AnnAt1-8), which range from 29% to 83% in deduced amino acid sequence identity. As a first step toward clarifying the individual functions of these annexins, in this study we have used quantitative real time reverse transcription PCR to assess their differential expression in different tissues or after different stimuli. We determined which annexins are expressed during germination and early seedling growth by assaying annexin expression levels in dry and germinating seeds and in 7-day-old light-grown seedlings. Our results indicate that transcripts for all eight annexins are present in germinating seeds and that transcript levels for all the annexins increase by 7 days of normal growth. We assayed transcript levels in dark grown roots, cotyledons, and hypocotyls and found that the relative abundance of each annexin varied in these dark-grown tissues. We also examined the effects of red and far red light treatments on annexin expression in 5.5-day-old etiolated seedlings. Light treatments significantly altered transcript levels in hypocotyls and cotyledons for only two members of the gene family. Finally, we monitored annexin expression changes in response to a variety of abiotic stresses. We found that the expression of most of the Arabidopsis annexin genes is differentially regulated by exposure to salt, drought, and high- and low-temperature conditions, indicating a likely role for members of this gene family in stress responses.

Lyme Meningoradiculitis and Myositis after Allogeneic Hematopoietic Stem Cell Transplantation

We describe a patient with a history of allogeneic hematopoietic stem cell transplantation complicated by chronic graft-versus-host disease who developed painful meningoradiculitis and myositis due to Lyme borreliosis. To our knowledge, this is the first report of such an infection occurring after allogeneic hematopoietic stem cell transplantation in the United States.

Human cytomegalovirus glycoprotein N (gpUL73-gN) genomic variants: identification of a novel subgroup, geographical distribution and evidence of positive selective pressure

Human cytomegalvirus (HCMV) ORF UL73 is a polymorphic locus, encoding the viral glycoprotein gpUL73-gN, a component of the gC-II envelope complex. The previously identified gN genomic variants, denoted gN-1, gN-2, gN-3 and gN-4, were further investigated in this work by analysing a large panel of HCMV clinical isolates collected from all over the world (223 samples). Sequencing and phylogenetic analysis confirmed the existence of the four gN genotypes, but also allowed the identification of a novel subgroup belonging to the gN-3 genotype, which was designated gN-3b. The number of non-synonymous (d(N)) and synonymous (d(S)) nucleotide substitutions and their ratio (d(N)/d(S)) were estimated among the gN genotypes to evaluate the possibility of positive selection. Results showed that the four variants evolved by neutral (random) selection, but that the gN-3 and gN-4 genotypes are maintained by positive selective pressure. The 223 HCMV clinical isolates were subdivided according to their geographical origin, and four main regions of gN prevalence were identified: Europe, China, Australia and Northern America. The gN variants were found to be widespread and represented within the regions analysed without any significant difference, and no new genotype was detected. Finally, for clinical and epidemiological purposes, a rapid and low-cost method for genetic grouping of the HCMV clinical isolates was developed based on the RFLP revealed by SacI, ScaI and SalI digestion of the PCR-amplified UL73 sequence. This technique enabled us to distinguish all four gN genomic variants and also their subtypes.

Sequencing of cytomegalovirus UL97 gene for genotypic antiviral resistance testing

The widespread use of ganciclovir (GCV) to treat cytomegalovirus (CMV) infections in immunosuppressed patients has led to the development of drug resistance. Phenotypic assays for CMV drug resistance are presently too time-consuming to be therapeutically useful. To support the development of genotypic assays for GCV resistance, the complete sequences of the UL97 phosphotransferase genes in 28 phenotypically GCV-sensitive CMV clinical isolates were determined. The gene was found to be highly conserved, with nucleotide sequence identity among strains ranging from 98.6 to 100% and amino acid sequence identity of >99%. Primers for a genotypic assay were designed to amplify codons 400 to 707, because all known UL97 mutations conferring drug resistance occur at three sites within this region. This part of the UL97 gene was amplified from over 50 clinical isolates, and two sequencing reactions for the coding strand were successfully used to identify GCV resistance mutations. This genotypic assay can be performed in 48 h using genomic DNA extracted from cell monolayers at very low levels of virus infectivity, thus rapidly providing therapeutically useful results.

Mining time dependency patterns in clinical pathways

Clinical pathways are widely adopted by many large hospitals around the world in order to provide high-quality patient treatment and reduce the length of hospital stay of each patient. The development of clinical pathways is a lengthy process, and may require the collaboration among physicians, nurses, and staffs in a hospital. However, the individual differences cause great variances in the execution of clinical pathways. It calls for a more dynamic and adaptive process to improve the performance of clinical pathways. This paper reports a data mining technique we have developed to discover the time dependency pattern of clinical pathways for managing brain stroke. The mining of time dependency pattern is to discover patterns of process execution sequences and to identify the dependent relation between activities in a majority of cases. By obtaining the time dependency patterns, we can predict the paths for new patients when he/she is admitted into a hospital; in turn, the health care procedure will be more effective and efficient.

Testing of alkaline and enzymatic hydrolysis pretreatments for fat particles in slaughterhouse wastewater

Four pretreatments to hydrolyse and/or reduce the size of fat particles in slaughterhouse wastewater (SHW) were tested: sodium hydroxide and three lipases of plant, bacterial and animal (pancreatic) origin. Hydrolysing agents and SHW containing between 2.5 and 3 g/l of fat particles were mixed at room temperature for 4 h. Additions of 5-400 meq NaOH/l did not increase soluble COD (SCOD) in SHW, but the average particle size was reduced to 73% +/- 7% of the initial average particle size (D(in)) at NaOH concentrations ranging from 150 to 300 meq/l. Pretreatment with pancreatic lipase PL-250 reduced the average particle size to a maximum of 60% +/- 3% of D(in). As D(in) was decreased from 359 to 68 microns, the enzyme concentration required to obtain the maximum particle size reduction increased from 200 to 1000 mg/l. A 4-h pretreatment with PL-250 also increased the free long-chain fatty acid (LCFA) concentration to a maximum of 15.5 mg/l, indicating some solubilization of the pork fat particles in SHW. SCOD was not significantly increased by the pretreatment, but SCOD was not found to be a good indicator of enzymatic lipolysis because of enzyme adsorption on the fat particle surface. Pancreatic lipase appeared more efficient with beef fat than pork fat, possibly because beef fat contains less polyunsaturated fatty acids than pork fat. The bacterial lipase LG-1000 was also efficient in reducing average fat particle size, but high doses (> 1000 mg/l) were required to obtain a significant reduction after 4 h of pretreatment. SCOD was not increased by pretreatment with LG-1000. No particle size reduction or changes in SCOD were noted after 4 h of pretreatment with the plant lipase EcoSystem Plus. It was concluded that PL-250 was the best pretreatment to hydrolyse fat particles in SHW. However, its impact on the efficiency of a downstream anaerobic digestion process remains to be tested.

Heterogenous and homogenous catalytic oxidation by supported gamma-FeOOH in a fluidized-bed reactor: kinetic approach

Oxidation of benzoic acid (BA) by H2O2 was performed with a novel supported gamma-FeOOH catalyst in a circulating fluidized-bed reactor (CFBR). This study focused mainly on determining the proportions of homogeneous catalysis and heterogeneous catalysis in this CFBR. Also studied herein was how pH, H2O2 concentration, and BA concentration affect the oxidation of BA. Experimental results indicate that the decomposition rate of H2O2 was proportional to its concentration and that the oxidation rate of BA depended on both H2O2 and BA concentrations. The change in the rate constant of heterogeneous catalysis by pH was described in terms of ionization fractions of surface hydroxyl group. From the mathematical deduction, we can infer thatthe reaction rate associated with ...Fe(III)OH2+ is markedly higher than that with ...Fe(III)OH. Conclusively, although heterogeneous catalysis contributes primarily to the oxidation of BA at pH 4.4-7.0, the homogeneous catalysis is of increasing importance below pH 4.4 because of the reductive dissolution of gamma-FeOOH.

Treatment of progressive hepatitis C recurrence after liver transplantation with combination interferon plus ribavirin

Hepatitis C virus (HCV) recurrence after orthotopic liver transplantation (OLT) is common, although the majority of cases are mild. A subset of transplant recipients develops progressive allograft injury, including cirrhosis and allograft failure. Minimal data are available on the safety and efficacy of antiviral treatment in this group of patients. The aim of this study is to review our experience in the treatment of moderate to severe HCV recurrence with combination interferon-alpha2b and ribavirin (IFN/RIB). Between October 1993 and October 1999, a total of 197 patients underwent OLT for HCV-related liver failure. This study describes 12 transplant recipients with moderate to severe recurrence treated with IFN/RIB. All patients met at least 1 of the following inclusion criteria: (1) moderate to severe inflammation (grade III to IV) on allograft biopsy, (2) bridging fibrosis on allograft biopsy, or (3) severe cholestasis attributable solely to HCV recurrence. Two patients had undergone re-OLT for allograft cirrhosis secondary to HCV recurrence and now had evidence of progressive HCV in their second allografts. Appropriate dose reductions of both IFN and RIB, as well as initiation of granulocyte colony-stimulating factor (G-CSF), for marked leukopenia were recorded. IFN/RIB therapy was started 60 to 647 days post-OLT, and duration of therapy ranged from 39 to 515 days. Seven patients were administered G-CSF to successfully treat leukopenia. Six of the 12 patients (50%) became HCV RNA negative by polymerase chain reaction. One of these 6 patients (no. 1) was HCV RNA negative at 6 months but chose to discontinue therapy because of intolerable side effects, experienced a relapse, and was HCV RNA positive at 12 months. Two of the remaining 5 patients were HCV RNA negative at 2 and 9 months off therapy. For the entire group, there was a statistically significant decrease in serum biochemical indices assessed at initiation of therapy and 1, 3, and 6 months into therapy. Most patients required dose reductions of both IFN and RIB. Five patients died; 3 patients died of liver-related complications that included severe intrahepatic biliary cholestasis, severe HCV recurrence, and chronic rejection with profound cholestasis. In the subset of HCV-positive liver transplant recipients with moderate to severe recurrence, combination IFN/RIB therapy resulted in complete virological response (serum RNA negative) in 6 of 12 patients ( approximately 50%). However, only 1 of 12 patients (8.3%) had sustained virological clearance after cessation of IFN/RIB therapy. Dose reductions of both IFN and RIB were required in most patients. The use of G-CSF (sometimes preemptively) allowed correction of leukopenia and full-dose antiviral therapy. Multicenter trials using combination therapy to identify factors predictive of response are needed in the subset of patients with progressive allograft injury.

A deletion mutation in region V of the cytomegalovirus DNA polymerase sequence confers multidrug resistance

A patient with AIDS and cytomegalovirus (CMV) retinitis received ganciclovir and foscarnet for 20 and 5 months, respectively, with evidence of periodic disease progression. After this therapy, a CMV isolate from the patient was resistant to ganciclovir, foscarnet, and cidofovir. Sequence analysis showed a known ganciclovir resistance mutation in the viral UL97 phosphotransferase (L595F) and a new mutation in conserved region V of the DNA polymerase gene (pol) sequence (codons 981-982 deleted). The pol mutation was transferred to a laboratory CMV strain (Towne) by homologous recombination and selection with either ganciclovir or foscarnet. Recombinant viruses containing this deletion showed a 6-8-fold increased ganciclovir resistance and a 3-5-fold increased resistance to both foscarnet and cidofovir, compared with the wild-type CMV. A single mutation in region V of CMV pol can, therefore, confer multiple drug resistance in a clinical isolate.

Preferential accessibility of the yeast his3 promoter is determined by a general property of the DNA sequence, not by specific elements

Yeast promoter regions are often more accessible to nuclear proteins than are nonpromoter regions. As assayed by HinfI endonuclease cleavage in living yeast cells, HinfI sites located in the promoters of all seven genes tested were 5- to 20-fold more accessible than sites in adjacent nonpromoter regions. HinfI hypersensitivity within the his3 promoter region is locally determined, since it was observed when this region was translocated to the middle of the ade2 structural gene. Detailed analysis of the his3 promoter indicated that preferential accessibility is not determined by specific elements such as the Gcn4 binding site, poly(dA-dT) sequences, TATA elements, or initiator elements or by transcriptional activity. However, progressive deletion of the promoter region in either direction resulted in a progressive loss of HinfI accessibility. Preferential accessibility is independent of the Swi-Snf chromatin remodeling complex, Gcn5 histone acetylase complexes Ada and SAGA, and Rad6, which ubiquitinates histone H2B. These results suggest that preferential accessibility of the his3 (and presumably other) promoter regions is determined by a general property of the DNA sequence (e.g., base composition or a related feature) rather than by defined sequence elements. The organization of the compact yeast genome into inherently distinct promoter and nonpromoter regions may ensure that transcription factors bind preferentially to appropriate sites in promoters rather than to the excess of irrelevant but equally high-affinity sites in nonpromoter regions.

Detection of unsuspected colonic abnormalities using the pneumocolon technique during small bowel meal examination

AIMS

The pneumocolon technique in small bowel meal examination is used to obtain double-contrast views of the distal ileum. The purpose of this study was to determine the proportion of cases in which an overhead pneumocolon radiograph demonstrated clinically relevant findings in the colon.

METHODS

The overhead pneumocolon radiographs in 151 patients who underwent small bowel meals were evaluated retrospectively. A chart review was performed on those patients with positive colonic findings to determine if the suspected abnormalities affected patient management.

RESULTS

Colonic abnormalities were identified in 34 of the 151 patients. One patient had a previously undiagnosed ascending colonic cancer; 17 had evidence of acute or chronic colitis; 13 had diverticulosis; one had a caecal polyp; one had an ileosigmoid fistula; one had a filling defect in the ascending colon. In 25 cases the colonic abnormality was visible only on the pneumocolon radiograph and not on the preceding single-contrast images. Management was altered by the colonic findings in seven cases. False-positive findings occurred in two cases.

CONCLUSIONS

A routine overhead radiograph following use of the pneumocolon technique is a useful adjunct to small bowel meal examination as it can yield unsuspected and clinically significant colonic findings.Chou, S. (2000). Clinical Radiology55, 459-464.

Efficacy and safety of patient-controlled analgesia for morbidly obese patients following gastric bypass surgery

BACKGROUND

Adequate postoperative pain control is important to reduce potential cardiopulmonary complications. It is often difficult to determine dosages of narcotics for morbidly obese patients following Roux-en-Y gastric bypass (RYGBP) due to respiratory depression. Individualization of analgesic therapy, patient-controlled analgesia (PCA), can provide optimal dosage for pain control and minimize the side-effects.

METHOD

25 morbidly obese patients who received PCA with morphine sulfate following RYGBP. PCA settings we re as follows: morphine, 20 microg/kg of ideal body weight, 10-minute lock out interval and 80 % of a calculated amount for a 4-hour limit. W e measured arterial blood gas, heart rate, mean arterial pressure, arterial oxygen saturation, respiratory rate, opioid amount, patient satisfaction, visual analog pain scale (VAS), and the incidence of nausea, vomiting, pruritus and sedation.

RESULTS

Average morphine usage was 44.2+/-28.7 mg during the day of surgery (DOS); 49.1+/-27.4 mg during POD (postoperative day) #1; and 36.6+/-22.8 mg during POD#2 (p < 0.01). 24 patients were satisfied with their pain control on POD#1. VAS was 5.4+/-2.1 on the day of surgery, but remained below 4 thereafter. Arterial oxygen saturation and vital signs were maintained without significant changes. 5 patients experienced mild sedation on the day of surgery and 3 patients experienced mild sedation on POD#1. 1 patient experienced nausea and vomiting and 4 patients had pruritus; however, none required treatment.

CONCLUSION

PCA is safe and effective for morbidly obese patients following RYGBP.

A standardized plaque reduction assay for determination of drug susceptibilities of cytomegalovirus clinical isolates

Twelve laboratories collaborated in formulating and testing a standardized plaque reduction assay for cytomegalovirus (CMV) cell-associated clinical isolates. Four characterized and plaque-purified CMV strains, as well as six coded clinical isolates obtained after antiviral therapy, were distributed and tested. Good agreement was obtained for four of the clinical isolates, but a broad distribution of results was obtained for two isolates. Analysis of these results indicates the problems associated with clinical isolates, including the large genetic variability and the highly cell-associated phenotype. This collaborative effort, by addressing these problems, represents a significant step toward the development of a standardized assay.

Pitfalls in the interpretation of MIBG scans in cervical neuroblastoma

Cervical neuroblastoma (CNB) is relatively rare, accounting for less than 5% of these tumors. Because it arises from the cervical sympathetic chain, complete resection will leave the child with Horner's syndrome in a high proportion of cases. Advances in technology have allowed for the development of diagnostic and imaging modalities more specific to the disease. One of these has been the advent of radiolabeled meta-iodobenzylguanidine (MIBG) to assess the primary tumor and focal metastatic involvement. This nuclide is also taken up by normal salivary-gland tissue; this may be altered, however, in the presence of sympathetic denervation. We present a case of a primary CNB associated with Horner's syndrome, which led to confusion in interpretation of the subsequent MIBG scan. We alert the reader to potential pitfalls in the use of this examination in this disease entity.

A nine-codon deletion mutation in the cytomegalovirus UL97 phosphotransferase gene confers resistance to ganciclovir

A deletion mutation (codons 595 to 603) in the cytomegalovirus (CMV) UL97 gene was recently reported after sequence analysis of leukocyte DNA from a patient receiving ganciclovir. The corresponding viral phenotype was examined by transfer of this mutation to a laboratory CMV strain (strain Towne). The recombinant virus was resistant to ganciclovir (8.4-fold increase in the 50% inhibitory concentration), was sensitive to foscarnet, and replicated normally in cell culture.

Donor polymorphism of tumor necrosis factor gene: relationship with variable severity of hepatitis C recurrence after liver transplantation

BACKGROUND

Hepatitis C-related liver failure is the leading indication for liver transplantation worldwide. Although histologic recurrence is identified in the majority of patients, the spectrum of allograft injury is wide. To date, most studies have focused on the contribution of immunosuppression and viral factors. We hypothesized that the allograft plays a significant role in determining timing and severity of hepatitis C virus (HCV) recurrence. The purpose of this analysis was to determine if genetic polymorphisms of the tumor necrosis factor (TNF) locus were associated with the highly variable severity of HCV recurrence.

METHODS

Thirty-one HCV-seropositive liver transplant recipients with long-term follow-up were studied. Genomic DNA was extracted from archived donor spleens which corresponded to each patient. We performed polymerase chain reaction amplification, followed by sequencing for two promoter TNF-alpha variants (at positions -238 and -308), and restriction fragment length analysis for four polymorphic loci within the TNF-beta gene (NcoI, TNFc, aa13, and aa26).

RESULTS

The relative prevalence of polymorphisms corresponded to distributions previously reported in normal control populations. Twenty-two of 31 (71%) patients received a donor liver homozygous for the wild type allele (TNF1) at the -308 TNF-alpha promoter region. The interval to histologic recurrence was significantly shorter and severity of HCV allograft hepatitis was significantly greater in patients with one or two TNF308.2 alleles. At last follow-up biopsy, 5 of 9 (56%) patients with a TNF308.2 donor liver had evidence of severe histological activity index as compared to 2 of 22 (9%) of patients receiving a donor liver homozygous for the TNF1 allele (P = 0.01). There was no correlation between rejection rates and the presence of any TNF-alpha or TNF-beta alleles. TNF-beta polymorphisms within the donor liver did not correlate with severity of HCV recurrence.

CONCLUSIONS

The donor TNF-alpha promoter genotype may influence the inflammatory response to HCV reinfection of the graft and contribute to accelerated graft injury. If the association between this genetic marker (TNF308.2) and disease progression is confirmed, it could improve our understanding of HCV pathogenesis and influence donor selection and patient management.

Transcriptional activation in yeast cells lacking transcription factor IIA

The general transcription factor IIA (TFIIA) forms a complex with TFIID at the TATA promoter element, and it inhibits the function of several negative regulators of the TATA-binding protein (TBP) subunit of TFIID. Biochemical experiments suggest that TFIIA is important in the response to transcriptional activators because activation domains can interact with TFIIA, increase recruitment of TFIID and TFIIA to the promoter, and promote isomerization of the TFIID-TFIIA-TATA complex. Here, we describe a double-shut-off approach to deplete yeast cells of Toa1, the large subunit of TFIIA, to <1% of the wild-type level. Interestingly, such TFIIA-depleted cells are essentially unaffected for activation by heat shock factor, Ace1, and Gal4-VP16. However, depletion of TFIIA causes a general two- to threefold decrease of transcription from most yeast promoters and a specific cell-cycle arrest at the G2-M boundary. These results indicate that transcriptional activation in vivo can occur in the absence of TFIIA.

Association of multispecific CD4(+) response to hepatitis C and severity of recurrence after liver transplantation

BACKGROUND & AIMS

After liver transplantation for hepatitis C virus (HCV), reinfection of the allograft invariably occurs. Indirect evidence suggests that the cellular immune response may play a central role. The purpose of this analysis was to determine the correlation between HCV-specific peripheral CD4(+) T-cell responses and the severity of recurrence after liver transplantation.

METHODS

Fifty-eight HCV-seropositive patients, including 43 liver transplant recipients with at least 1 year of histological follow-up, were studied. Peripheral blood mononuclear cells (PBMCs) were isolated from fresh heparinized blood and stimulated with either recombinant HCV antigens (core, E2, NS3, NS4, and NS5) or control antigens.

RESULTS

Fourteen (40%) of 35 patients with mild or no evidence of histological recurrence within their allografts responded to at least 1 of the HCV antigens. Eleven responded to NS3, 5 to all the nonstructural antigens, and 3 to the HCV core polypeptide alone. In contrast, in the 8 patients with severe HCV recurrence, no proliferation in response to any of the HCV antigens was seen (P = 0. 03) despite responses to the control antigens.

CONCLUSIONS

Despite immunosuppression, HCV-specific, major histocompatibility complex class II- restricted CD4(+) T-cell responses are detectable in patients with minimal histological recurrence after liver transplantation. In contrast, PBMCs from patients with severe HCV recurrence, despite being able to proliferate in response to non-HCV antigens, fail to respond to the HCV antigens. These findings suggest that the inability to generate virus-specific T-cell responses plays a contributory role in the pathogenesis of HCV-related graft injury after liver transplantation. It is hoped that further characterization of the immunoregulatory mechanisms related to recurrent HCV will provide the rationale for novel therapeutic strategies and diminish the incidence of inevitable graft loss.