SARS-CoV-2 infection in children with cystic fibrosis: A cross-sectional multicenter study in Spain. New waves, new knowledge

INTRODUCTION

The association between viral infections and pulmonary exacerbations in children with cystic fibrosis (cwCF) is well established. However, the question of whether cwCF are at a higher risk of COVID-19 or its adverse consequences remains controversial.

METHODS

We conducted an observational, multicenter, cross-sectional study of cwCF infected by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) between March 2020 and June 2022, (first to sixth COVID-19 pandemic waves) in Spain. The study aimed to describe patients' basal characteristics, SARS-CoV-2 clinical manifestations and outcomes, and whether there were differences across the pandemic waves.

RESULTS

During study time, 351 SARS-CoV2 infections were reported among 341 cwCF. Median age was 8.5 years (range 0-17) and 51% were female. Cases were unevenly distributed across the pandemic, with most cases (82%) clustered between November 2021 and June 2022 (sixth wave, also known as Omicron Wave due to the higher prevalence of this strain in that period in Spain). Most cwCF were asymptomatic (24.8%) or presented with mild Covid-19 symptoms (72.9%). Among symptomatic, most prevalent symptoms were fever (62%) and increased cough (53%). Infection occurring along the sixth wave was the only independent risk factor for being symptomatic. Just eight cwCF needed hospital admission. No multisystem inflammatory syndrome, persisting symptoms, long-term sequelae, or deaths were reported.

CONCLUSIONS

Spanish current data indicate that cwCF do not experience higher risks of SARS-CoV-2 infection nor worse health outcomes or sequelae. Changes in patients' basal characteristics, clinical courses, and outcomes were detected across waves. While the pandemic continues, a worldwide monitoring of COVID-19 in pediatric CF patients is needed.

Aortic dysfunction by chronic cadmium exposure is linked to multiple metabolic risk factors that converge in anion superoxide production

CONTEXT

The chronic exposure to Cadmium (Cd) constitute an risk to develop hypertension and cardiovascular diseases associated with the increase of oxidative stress.

OBJECTIVE

In this study, we investigate the role of metabolic changes produced by exposure to Cd on the endothelial dysfunction via oxidative stress.

METHODS

Male Wistar rats were exposed to Cd (32.5-ppm) for 2-months. The zoometry and blood pressure were evaluated, also glucose and lipids profiles in serum and vascular reactivity evaluated in isolated aorta rings.

RESULTS

Rats exposed to Cd showed an increase of blood pressure and biochemical parameters similar to metabolic syndrome. Additionally, rats exposed to Cd showed a reduced relaxation in aortic rings, which was reversed after the addition of SOD and apocynin an inhibitor of NADPH.

CONCLUSION

The Cd-exposition induced hypertension and endothelial injury by that modifying the vascular relaxation and develop oxidative stress via NADPH oxidase, superoxide and loss nitric oxide bioavailability.

The Respiratory Microbiome in Cystic Fibrosis: Compartment Patterns and Clinical Relationships in Early Stage Disease

We compared the bacterial microbiomes lodged in the bronchial tree, oropharynx and nose of patients with early stage cystic fibrosis (CF) not using chronic antibiotics, determining their relationships with lung function and exacerbation frequency. CF patients were enrolled in a cohort study during stability and were checked regularly over the following 9 months. Upper respiratory samples (sputum [S], oropharyngeal swab [OP] and nasal washing [N]) were collected at the first visit and every 3 months. 16S rRNA gene amplification and sequencing was performed and analyzed with QIIME. Seventeen CF patients were enrolled (16.6 SD 9.6 years). Alpha-diversity of bacterial communities between samples was significantly higher in S than in OP (Shannon index median 4.6 [IQR: 4.1–4.9] vs. 3.7 [IQR: 3-1-4.1], p = 0.003/Chao 1 richness estimator median 97.75 [IQR: 85.1–110.9] vs. 43.9 [IQR: 31.7–59.9], p = 0.003) and beta-diversity analysis also showed significant differences in the microbial composition of both respiratory compartments (Adonis test of Bray Curtis dissimilarity matrix, p = 0.001). Dominant taxa were found at baseline in five patients (29.4%), who showed lower forced expiratory volume in the first second (FEV1%, mean 74.8 [SD 19] vs. 97.2 [SD 17.8], p = 0.035, Student t test). The Staphylococcus genus had low RAs in most samples (median 0.26% [IQR 0.01–0.69%]), but patients with RA > 0.26% of Staphylococcus in bronchial secretions suffered more exacerbations during follow-up (median 2 [IQR 1–2.25] vs. 0 [0–1], p = 0.026. Mann–Whitney U test), due to S. aureus in more than a half of the cases, microorganism that often persists as bronchial colonized in these patients (9/10 [90%] vs. 2/7 [28.6%], p = 0.034, Fisher’s exact test). In conclusion, the bronchial microbiome had significantly higher diversity than the microbial flora lodged in the oropharynx in early stage CF. Although the RA of the Staphylococcus genus was low in bronchial secretions and did not reach a dominance pattern, slight overrepresentations of this genus was associated with higher exacerbation frequencies in these patients.

The Role of Occlusal Factors in the Presence of Noncarious Cervical Lesions in Young People: A Case-Control Study

Objective:

The aim of this retrospective case-control study was to evaluate the influence of different occlusal characteristics and self-referred bruxism in the presence of noncarious cervical lesions (NCCLs).

Methods and Materials:

The participants were 280 students (140 cases and 140 controls), with an average age of 24.5 years, from six schools of dentistry in Spain. Clinical examination was carried out to record the NCCLs and the static and dynamic occlusal characteristics. The side of mastication and bruxism was collected by questionnaire. Data variables were analyzed by means of univariate and multivariate logistic regression. Odds ratios and the respective 95% confidence intervals were calculated (p<0.05).

Results:

The presence of NCCLs was significantly more likely in subjects with protrusive interferences (odds ratio [OR]=1.82); with lateral interferences, especially on the nonworking side (OR= 1.77); or who were self-reported bruxists (OR=1.72). In the multivariate analysis, protrusive interferences, bruxism, age, and the presence of attrition were risk factors for the development of NCCLs. These factors resulted in a model with an area under the receiver-operating characteristic curve of 0.667 and a positive predictive value of 61.43%.

Conclusions:

There was no significant relationship between most occlusal factors and the presence of NCCLs. Only bruxism, protrusive interferences, age, and occlusal wear were risk factors. The predictive model was not sufficiently explanatory. Occlusal factors alone do not appear to be sufficient to explain the presence of NCCLs.

Hair-Cell Mechanotransduction Persists in TRP Channel Knockout Mice

Members of the TRP superfamily of ion channels mediate mechanosensation in some organisms, and have been suggested as candidates for the mechanotransduction channel in vertebrate hair cells. Some TRP channels can be ruled out based on lack of an inner ear phenotype in knockout animals or pore properties not similar to the hair-cell channel. Such studies have excluded Trpv4, Trpa1, Trpml3, Trpm1, Trpm3, Trpc1, Trpc3, Trpc5, and Trpc6. However, others remain reasonable candidates. We used data from an RNA-seq analysis of gene expression in hair cells as well as data on TRP channel conductance to narrow the candidate group. We then characterized mice lacking functional Trpm2, Pkd2, Pkd2l1, Pkd2l2 and Pkd1l3, using scanning electron microscopy, auditory brainstem response, permeant dye accumulation, and single-cell electrophysiology. In all of these TRP-deficient mice, and in double and triple knockouts, mechanotransduction persisted. Together with published studies, these results argue against the participation of any of the 33 mouse TRP channels in hair cell transduction.

Intragenic motifs regulate the transcriptional complexity of Pkhd1/PKHD1

Autosomal recessive polycystic kidney disease (ARPKD) results from mutations in the human PKHD1 gene. Both this gene, and its mouse ortholog, Pkhd1, are primarily expressed in renal and biliary ductal structures. The mouse protein product, fibrocystin/polyductin complex (FPC), is a 445-kDa protein encoded by a 67-exon transcript that spans >500 kb of genomic DNA. In the current study, we observed multiple alternatively spliced Pkhd1 transcripts that varied in size and exon composition in embryonic mouse kidney, liver, and placenta samples, as well as among adult mouse pancreas, brain, heart, lung, testes, liver, and kidney. Using reverse transcription PCR and RNASeq, we identified 22 novel Pkhd1 kidney transcripts with unique exon junctions. Various mechanisms of alternative splicing were observed, including exon skipping, use of alternate acceptor/donor splice sites, and inclusion of novel exons. Bioinformatic analyses identified, and exon-trapping minigene experiments validated, consensus binding sites for serine/arginine-rich proteins that modulate alternative splicing. Using site-directed mutagenesis, we examined the functional importance of selected splice enhancers. In addition, we demonstrated that many of the novel transcripts were polysome bound, thus likely translated. Finally, we determined that the human PKHD1 R760H missense variant alters a splice enhancer motif that disrupts exon splicing in vitro and is predicted to truncate the protein. Taken together, these data provide evidence of the complex transcriptional regulation of Pkhd1/PKHD1 and identified motifs that regulate its splicing. Our studies indicate that Pkhd1/PKHD1 transcription is modulated, in part by intragenic factors, suggesting that aberrant PKHD1 splicing represents an unappreciated pathogenic mechanism in ARPKD. Key messages: Multiple mRNA transcripts are generated for Pkhd1 in renal tissues Pkhd1 transcription is modulated by standard splice elements and effectors Mutations in splice motifs may alter splicing to generate nonfunctional peptides.

P2-09-02: Predicting Response to Bevacizumab in Primary Breast Cancer Using 18F-Fluorothymidina (FLT) and 18F-Misonidazole (MISO) Positron Emission/Computed Tomography (PET/CT) as Imaging Biomarkers

Background: To investigate the hypothesis that early changes in tumor proliferation and hypoxic status induced by bevacizumab and assessed by imaging biomarkers might predict response to bevacizumab therapy.

Methods: 73 chemotherapy naïve, stage II-III breast cancer (BC) patients (pts) were enrolled in the training set of this phase II, single-arm, multicenter and prospective clinical trial from October 2009 until November 2010. Pts received single infusion of bevacizumab (15 mg/kg) (C1) 3 weeks prior to the beginning of neoadjuvant chemotherapy (NAC) consisting in 4 cycles of docetaxel (60 mg/mq), doxorubicin (50 mg/mq) and bevacizumab (15 mg/kg) every 21 days (C2-C5) following by surgery. Tumor proliferation and hypoxic status were evaluated using FLT and MISO PET/CT at baseline and 14–21 days after bevacizumab (C1). Standardized uptake values (SUV) for FLT and MISO and ratios to reference tissues, mediastinum (T/Me) or muscle (T/Mu), for MISO were calculated. Pathological response on surgical specimens was assessed according to Miller/Payne grading system. Pts with reduction in tumor cells >30% (G3-G4-G5) or <30% (G1-G2) were respectively considered as responders and no-responders. Association between pathological response, baseline and changes induced by bevacizumab (C1) in imaging biomarkers was analyzed using Mann-Whitney test. Receiver operating characteristic (ROC) curve was performed to test sensitivity and specificity of the biomarker found associated to response. Its value as independent predictor was tested in multivariate analysis using logistic regression. Results: Median baseline MISO and FLT SUV values in tumors were 1.2 (range 0.69−2.39) and 2.89 (range 0.97−7.18). Significant change after C1 was observed in FLT (2.7 vs 1.8, p<0.001) but no in MISO uptake. Fifty-two (74%) pts achieved response (G3-G4-G5) whether 18 (24%) were considered as no responder (G1-G2); for 3 (4%) patients Miller/Payne tumor evaluation was not available. Response showed a trend toward an association with negative estrogen receptors (ER) expression (p=0.08) and triple negative tumors (11/73) (p=0.05). FLT SUV baseline and changes after C1 in MISO SUV, T/Mu and T/Me were all significantly associated with pathological response (p=0.057, 0.03, 0.016, 0.010). ER expression and T/Mu change remained significantly associated with response in multivariate analysis (OR=24.8, IC95% 1.8-334, p=0.01 and OR=0.95, IC 95% 0.92−0.99, p value=0.02). Decrease in MISO T/Mu uptake >20% yielded a ROC curve area of 0.7 (95% CI: 0.56 - 0.85) with 94% sensitivity and 87% specificity. Conclusion: Bevacizumab determined a marked decrease in tumor proliferation. Interestingly, a decrease greater than 20% in tumor hypoxic status after C1 and assessed by MISO was found significantly associated with pathological response suggesting a potential value of early decrease in hypoxic tumor status as predictive biomarker of response. Bevacizumab, causing normalization of the tumor microvasculature, seems to potentiate the effect of cytotoxic agents on primary BC. A validation set is warranted to confirm these findings.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-09-02.

P2-08-05: Use of Dynamic Contrast-Enhanced MR Imaging To Predict Pathological Response in Primary Breast Cancer

Purpose: To investigate the effect of bevacizumab infusion on vascular parameters assessed by dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging and to test their association with pathological response in primary breast cancer.

Materials and Methods: 73 patients (median age, 47 ys; age range, 29–70 ys) with biopsy-proven, previously untreated, primary breast cancer were recruited from October 2009 to November 2010 in this phase II, multicenter and non-randomized clinical trial. Patients (pts) received single infusion of bevacizumab (15 mg/kg) (C1) 3 weeks prior to the beginning of neoadjuvant chemotherapy consisting in 4 cycles of docetaxel (60 mg/mq), doxorubicin (50 mg/mq) and bevacizumab (15 mg/kg) every 21 days (C2-C5) following by surgery. All pts underwent DCE-MR imaging before and 14–21 days after C1. Quantitative and semiquantitative kinetic parameters were calculated at baseline and after C1, including the volume transfer constant (K(trans)), which primarily reflects the wash-in of the contrast agent, the backflow rate contrant (K(ep)), extracellular volume fraction (V(e)) and the initial area under the gadolinium concentration-time curve over 60 seconds (IAUGC(60)). Changes in the DCE-MRI kinetic parameters K(trans), K(ep), V(e) and IAUGC(60) were calculated and Wilcoxon test was used to assess significant effects induced by bevacizumab on kinetic parameters. Pathological response on surgical specimens after C5 was assessed according to Miller and Payne classification. Pts with tumor reduction >30% were considered as responders (G3-G4-G5) whether tumor reduction <30% were considered as no responders (G1-G2). DCE-MR imaging parameters and clinical-pathological characteristics were correlated with pathological response using Mann-Whitney test in univariate and logistic regression in multivariate analyses. Receiver operating curves (ROC) was used to define the best cut-off of the parameter found associated with pathological response.

Results: DCE-MRI was performed before (n=72) and after (n=71) C1. K(trans), K(ep), V(e) and IAUCG(60) values were significantly different at the baseline and after C1 (p<0.01). Median changes were, respectively, −51, −101, −52.5 and −4.8. Fifty-two (74%) pts achieved response (G3-G4-G5) after C5 whether 18 (24%) were considered as no responder (G1-G2); for 3 (4%) patients Miller/Payne tumor evaluation was not available. At univariate analysis, negative estrogen receptor (ER) status and higher post-C1 K(ep) (p=.057) showed a trend toward an association with response. At multivariate analysis, only ER status remains a significant predictor of response (p= .04). Area under ROC curve for K(ep) was 0.65 (IC95% 0.05−0.8, p=.057)

Conclusion: Bevacizumab affects tumor vasculature, perfusion and permeability as showed by the significantly reduction in all kinetic vasculature parameters obtained in DCE-MR imaging after C1. However, in our population these changes were not associated with pathological response. On the other hand, backflow rate constant, K(ep), a perfusion-related parameter derived from DCE-MRI yielded after C1 major than 80, may be associated with higher pathological response with a specificity of 88% and sensitivity of 90%. Future studies are warranted to confirm these findings.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-08-05.

P5-13-04: Changes in Phosphorylation Status at VEGFR2 and Basal Tumor Hypoxic Volume Assessed by Misonidazol (MISO) Positron Emission Tomography (PET/CT) as Potential Biomarkers for Predicting Response to Bevacizumab in Breast Cancer

Background: To evaluate the expression of novel putative biomarkers as predictors of benefit from bevacizumab in stage II-III, previously untreated breast cancers (BC) patients (pts) in the context of a phase II, single-arm, multicenter and prospective clinical trial. To address this aim, we examined baseline and induced changes after a single bevacizumab administration as potential early predictors of response. Methods: Pts received a single infusion of bevacizumab (15 mg/kg) (C1) 3 weeks prior to the beginning of neoadjuvant chemotherapy consisting in 4 cycles of docetaxel (60 mg/mq), doxorubicin (50 mg/mq) and bevacizumab (15 mg/kg) every 21 days (C2-C5) following by surgery. Early assessment of tumor changes was performed by paired tumor-biopsies and MISO PET/CT before and 14–21 days after bevacizumab administration (C1). Biomarker expression was assessed by immunohistochemistry (IHC) (Ki67, CD31, CD31/Ki67, VEGFR2, pVEGFR2 [Y951]) on formalin-fixed, paraffin-embedded tissue before and after bevacizumab infusion (C1). MISO SUV and tumor volume depicted by PET were calculated. Pathological response on surgical specimens was assessed according to Miller/Payne classification. Pts with tumor reduction >90% were considered as best responders (G4-G5) whether tumor reduction <90% were considered as no responders. Association between pathological response, IHC and MISO biomarkers was analyzed using Mann-Whitney test. ROC curve was performed to test sensibility and specificity of the biomarker found significantly associated with response and its value as independent predictor was tested in the multivariate analysis using logistic regression.

Results: This analysis was performed on the training set including 73 patients (49 yr, range 29–70). Twenty (27%) patients obtained best response (G4-G5) whether 50 (68%) were considered as no responder (G1-G2-G3). Response was associated with negative estrogen receptors expression (p=0.02) and high Ki67 basal and after C1 expression (p=0.009 and p=0.01). Six (54%) of triple negative tumors were responders (p=0.05). Interestingly, change in pVEGFR2 [Y951] staining induced by bevacizumab administration and basaline MISO tumor volume was found significantly associated with response (p=0.03 and 0.057). Decrease in the phosphorilation status of VEGFR2 (Y951) >70% yielded a receiver operating characteristic (ROC) curve area of 0.681 (95% CI: 0.536 — 0.825) with 84% sensitivity and 95% specificity. The positive and negative predictive values for this marker were 60% and 64%, respectively. The change in phosphorilation status of VEGFR2p remains a significant predictor biomarker of response in multivariate analysis (OR=0.9, IC%95 0.96−0.99, p=0.04) after adjusting for clinical-pathological characteristics.

Conclusion: These findings underline the potential value of early decrease in phosphorilation status of VEGFR2 after bevacizumab infusion as predictive biomarker of response to anti-angiogenic therapy in breast cancer. Moreover, tumor hypoxic volume obtained by MISO might be associated with response. A validation set is warranted to confirm these findings.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-13-04.

A missense mutation in PKD1 attenuates the severity of renal disease

Mutations of PKD1 and PKD2 account for most cases of autosomal dominant polycystic kidney disease (ADPKD). Compared with PKD2, patients with PKD1 typically have more severe renal disease. Here, we report a follow-up study of a unique multigeneration family with bilineal ADPKD (NFL10) in which a PKD1 disease haplotype and a PKD2 (L736X) mutation co-segregated with 18 and 14 affected individuals, respectively. In our updated genotype-phenotype analysis of the family, we found that PKD1-affected individuals had uniformly mild renal disease similar to the PKD2-affected individuals. By sequencing all the exons and splice junctions of PKD1, we identified two missense mutations (Y528C and R1942H) from a PKD1-affected individual. Although both variants were predicted to be damaging to the mutant protein, only Y528C co-segregated with all of the PKD1-affected individuals in NFL10. Studies in MDCK cells stably expressing wild-type and mutant forms of PKD found that cell lines expressing the Y528C variant formed cysts in culture and displayed increased rates of growth and apoptosis. Thus, Y528C functions as a hypomorphic PKD1 allele. These findings have important implications for pathogenic mechanisms and molecular diagnostics of ADPKD.

Hepatitis C recurrence after liver transplantation: Viral and histologic response to full-dose PEG-interferon and ribavirin

Hepatitis C recurrence after liver transplantation (LT) is universal, and frequently leads to cirrhosis and death. The aim of our study was to assess the efficacy and safety of 48-weeks of full-dose peg-interferon-alpha-2a (n = 4) or alpha-2b (n = 51) plus ribavirin (>11 mg/kg/day) in a multicentric cohort of 55 patients > or =12 months after LT. All subjects had histologically proven HCV recurrence, excluding severe cholestatic recurrence. Mean age was 54.3 +/- 9.7, 77% male, 90.9% genotype 1, 32.7% cirrhotics. All but 5 patients received monotherapy with tacrolimus (54.5%), cyclosporine (30.7%) or mycophenolate mofetil (5.5%). The rates of end-of-treatment response and sustained virological response (SVR) were 66.7% and 43.6%, respectively. Low baseline HCV-RNA (p = 0.005) and a length from LT to therapy between 2-4 years (p = 0.011) were predictors of SVR. The lack of achieving a viral load decrease > or =1-log10 at week 4 and/or 2-log10 at week 12 was 100% predictive of failure. The most frequent side effects were neutropenia (76,4%), anemia (60%) and infectious complications (30.9%). Toxicity led to peg-interferon withdrawal in 16 (29%) subjects. In 15 patients with post-treatment biopsy, the histological activity index was significantly improved (p = 0.006), whereas fibrosis did not change (p = 0.14). Three patients died (cholangitis, hepatic artery thrombosis and lung cancer). In conclusion, HCV therapy after LT was very effective, although it led to a significant rate of toxicity.

Hepatitis C recurrence after liver transplantation: Viral and histologic response to full-dose PEG-interferon and ribavirin

Hepatitis C recurrence after liver transplantation (LT) is universal, and frequently leads to cirrhosis and death. The aim of our study was to assess the efficacy and safety of 48-weeks of full-dose peg-interferon-alpha-2a (n = 4) or alpha-2b (n = 51) plus ribavirin (>11 mg/kg/day) in a multicentric cohort of 55 patients > or =12 months after LT. All subjects had histologically proven HCV recurrence, excluding severe cholestatic recurrence. Mean age was 54.3 +/- 9.7, 77% male, 90.9% genotype 1, 32.7% cirrhotics. All but 5 patients received monotherapy with tacrolimus (54.5%), cyclosporine (30.7%) or mycophenolate mofetil (5.5%). The rates of end-of-treatment response and sustained virological response (SVR) were 66.7% and 43.6%, respectively. Low baseline HCV-RNA (p = 0.005) and a length from LT to therapy between 2-4 years (p = 0.011) were predictors of SVR. The lack of achieving a viral load decrease > or =1-log10 at week 4 and/or 2-log10 at week 12 was 100% predictive of failure. The most frequent side effects were neutropenia (76,4%), anemia (60%) and infectious complications (30.9%). Toxicity led to peg-interferon withdrawal in 16 (29%) subjects. In 15 patients with post-treatment biopsy, the histological activity index was significantly improved (p = 0.006), whereas fibrosis did not change (p = 0.14). Three patients died (cholangitis, hepatic artery thrombosis and lung cancer). In conclusion, HCV therapy after LT was very effective, although it led to a significant rate of toxicity.

Pegylated interferon and ribavirin for the recurrence of chronic hepatitis C genotype 1 in transplant patients

The efficacy of pegylated interferon (p-IFN) and ribavirin (RB) in transplant patients is not well known. Chronic hepatitis C evolves in a more aggressive form after transplantation, causing a worse survival. Twenty-one naïve patients with recurrent chronic hepatitis C demonstrated by biopsy were treated for 48 weeks with p-IFN alpha2b (1.5 microg/kg/wk) and RB (>10.6 mg/kg/d). Quantification of RNA was performed (Amplicor Cobas 2.0 Roche) at baseline, 4, 12, 24, 48, and 72 weeks. A qualitative technique was used when quantitative levels were undetectable. At more than 1 year since liver transplantation we did not detect coinfection with human immunodeficiency virus or use steroid treatment. Among the cohort there were 16 men (76.2%). The mean overall age was 52 +/- 12 years. Time from liver transplant to treatment was 1637 +/- 1030 days. They were all infected with genotype 1. Eight patients received cyclosporine and the others tacrolimus. One patient was coinfected with hepatitis B virus and was receiving lamivudine. The mean initial histological activity index was 6.9 +/- 1.5 and fibrosis, 2.52 +/- 1.8 (Ishak). Two patients needed spleen embolization before the treatment. Two patients had to stop the treatment: one due to clinical intolerance, and the other one due to a cholangitis. In 14%, p-IFN doses were adjusted. In 32% RB was adjusted. Five (23.8%) did not respond at 24 weeks. Fourteen (66.7%) showed end-treatment responses but four relapsed at 72 weeks. A sustained viral response was achieved in 9 (42.8%). One patient died due to arterial thrombosis just after completing the treatment.

Loss of polycystin-1 or polycystin-2 results in dysregulated apolipoprotein expression in murine tissues via alterations in nuclear hormone receptors

Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations of PKD1 and PKD2. Murine gene targeting studies have shown that these genes play an essential role in development, with homozygous inactivation resulting in embryonic lethality. Recently, Pkd1-/- lethality has been linked to placental insufficiency. In this study, the placenta was used as a model to identify factors involved in these developmental abnormalities. Microarray analysis of Pkd1-/- placentae showed upregulation of a set of apolipoprotein-related genes. These changes were validated and were found to be associated with increased quantities of apolipoproteins in the amniotic fluid. Increased apolipoprotein gene expression was also observed in Pkd2-/-placentae and in cystic kidneys of Pkd1cond/-; Meox2cre/+ mice. Using chromatin immunoprecipitation assays, we determined that the activity of HNF-4alpha, a major regulator of apolipoprotein gene expression, was also increased in these organs. These findings suggest a potential role for dysregulation of nuclear hormone receptors in the pathogenesis of ADPKD.

Variability of MELD Score During the Year Before Liver Transplantation

Model for end-stage liver disease (MELD) score is a good parameter to establish the patient survival before liver transplantation and give priority to the sickest patients. The aim of this study was to evaluate the variability and potential regression of MELD score during the months before liver transplant. From the 350 patients waitlisted for transplantation, we evaluated the 124 patients who had enough blood tests during 12 months before the final event (transplantation, death, removal from list due to improvement or worsening). We considered month 12 as the final event and blood tests from 0, 3, 6, and 12 months were analyzed. MELD score was calculated and compared using ANOVA for repeated measures test. To determine variability of MELD and its components, intraclass correlation coefficient (ICC) was calculated for 0, 3, and 6 months. The degree of constancy was defined by proximity of ICC to 1. Two groups by initial MELD (< or =17 or >17) were considered. Patient data are: mean age, 53 +/- 9 years; sex: 70% men, etiology, 28% hepatitis C, 11% alcohol and hepatitis C, 16% alcohol, 28% hepatocellular carcinoma, 6% hepatitis B, 11% others; Initial Child-score, 8.5 +/- 2.0; Initial MELD score, 15.2 +/- 4.9; mean time on waiting list, 8.1 +/- 5.7 months. MELD score from 6 and 12 months was significantly higher than the initial one. The most constant parameter was creatinine (ICC:0.89); bilirubin (ICC:0.58) and INR (ICC:0.59) were the most variable ones. MELD score ICC was 0.79. In only one patient did MELD score decrease 5 points below the initial one. For initial MELD < or = 17 and >17, variability was lower in the former. In conclusion, MELD became significantly higher 6 months after the basal determination. This score is reliable as it does not tend to decrease in time. In high MELD scores (>17), 3-month survival was lower and variability greater so that more careful follow-up and prioritizing are needed.

Is liver transplantation advisable for isoniazid fulminant hepatitis in active extrapulmonary tuberculosis?

Antituberculous treatment is a well-known cause of fulminant hepatic failure (FHF). This could lead to liver transplantation as the only possible treatment, which on the other hand could be contraindicated due to active tuberculosis. The risk of aggressive dissemination of the disease after transplantation is not clearly determined by the current second-line antituberculous therapies. We report a case of vertebral tuberculosis treated with rifampin, isoniazid and pyrazinamide. He developed an FHF that was treated with urgent liver transplantation. Despite the immunosuppression, the disease was well controlled with ciprofloxacin, ethambutol and streptomycin and the patient is in good health 23 months after transplantation. In conclusion, active extrapulmonary tuberculosis should perhaps be considered for liver transplantation when FHF develops due to anti-tuberculous drugs.

Elevated levels of oxidized low-density lipoprotein and impaired nocturnal synthesis of melatonin in patients with myocardial infarction

This study was designed to investigate the relationship between nocturnal serum melatonin (MEL) levels and oxidized low-density lipoprotein (OxLDL) in patients with acute coronary syndrome (ACS). OxLDL plays a pivotal role in the development of atherosclerosis. Patients with coronary heart disease have an impaired nocturnal secretion of MEL. To date, there are no clinical human studies concerning the relationship of MEL to low-density lipoprotein (LDL) oxidation in patients with acute myocardial infarction (AMI). The study population contained 60 patients with AMI and 60 control subjects. Levels of circulating OxLDL were measured by a monoclonal antibody 4E6-based competition ELISA. Levels of circulating MEL were measured by an enzyme-immunoassay kit after chloroform extraction. Comparison of levels between AMI and controls, adjusted for age, revealed significantly higher nocturnal serum OxLDL levels (95.47+/-6.81 versus 68.35+/-4.07 U/l; p=0.004) in the AMI subjects. Nocturnal serum levels of MEL were lower in AMI than the control group (20.97+/-3.90 versus 53.19+/-7.80 pg/ml; p=0.009). Serum levels of total, high-density lipoprotein (HDL), and LDL cholesterol did not differ between the groups. Multiple regression analysis was performed on cases to study the association between AMI and serum levels of OxLDL and MEL (OR: 2.93; 95% CI, 2.89-2.98, p=0.01 and OR: 0.94; 95% CI, 0.89-0.97, p=0.02, respectively). This study demonstrates for the first time an independent association between nocturnal levels of OxLDL and MEL in patients with AMI. Additional population studies are necessary to further document these.

Macrolipasemia and celiac disease

A case of undiagnosed celiac disease associated with macrolipasemia and macroamylasemia is reported. This association is almost unique. To our knowledge, only one case has been previously diagnosed. Previous case reports about macroamylasemia and celiac disease, as well as macrolipasemia, are briefly discussed.

Invasive pulmonary aspergillosis: a rare presentation of non-Hodgkin's lymphoma

We describe a patient with rapidly progressive pneumonia and a high level of serum lactate dehydrogenase, in whom postmortem study revealed the presence of a diffuse, small and large-cell multicentric non-Hodgkin's lymphoma, together with an invasive pulmonary aspergillosis. Aspergillosis is rare as a presenting feature of a lymphoproliferative disease; only one previous case has been reported to the best of our knowledge. Invasive aspergillosis and lymphoma should be considered in patients presenting with pneumonia and high level of lactate dehydrogenase.

Homeostatic restoration of microsomal lipids and enzyme changes in HMG-CoA reductase and acyl-CoA: cholesterol acyltransferase in chick liver

We have studied the correlation between changes in the lipid composition in chick liver microsomes and the activities of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA reductase) and acyl-CoA: cholesterol acyltransferase (ACAT) by in vivo and in vitro experiments with 21-day-old chicks. A 5% cholesterol diet for 3 hr produced an increase in the microsomal and plasmatic cholesterol content, a decrease in HMG-CoA reductase activity and a concomitant increase in ACAT activity. The effect produced by the short-term treatment virtually disappeared 27 hr after ending the cholesterol diet. In vitro experiments were carried out by using vesicles constituted by phosphatidylcholine/cholesterol and phosphatidylcholine.

Correlation between changes in membrane lipid composition induced by dietary lipid and membrane-bound enzyme activity in chick liver

The activity of acyl-CoA: cholesterol acyltransferase in the liver-microsomal fraction was considerably reduced in chicks fed on diet containing unsaturated fat, whereas the activity of HMG-CoA reductase and NADPH cytochrome c reductase was not affected. The fatty acid composition of the microsomes was modified appreciably by this dietary condition and there was no change in the phospholipid or cholesterol levels. The addition of cholesterol to the fat supplemented diet resulted in a considerable increase in the microsomal cholesterol content. A decrease in HMG-CoA reductase and an increase ACAT activity was observed compared with the corresponding values from both the groups fed on a standard diet and a fat supplemented diet with no cholesterol. These results suggest that acyl-CoA: cholesterol acyltransferase is modulated by alteration in the fatty acid composition of the microsomal membrane, while the cholesterol content of the microsomes shows a close relationship with the HMG-CoA reductase activity.

Optimization of a rapid test by using fluorescein-conjugated monoclonal antibodies for detection of Chlamydia trachomatis in clinical specimens

A mixture of two fluorescein isothiocyanate-conjugated monoclonal antibodies (MAbs) was used to optimize a direct specimen test (Chlamydia Direct Specimen Test IF; Clonatec, Paris, France) for detection of chlamydial elementary bodies in clinical specimens. One MAb reacted with a subspecies-specific epitope of the major outer membrane protein (molecular weight 43,000) of Chlamydia trachomatis, whereas the other reacted with the periodate-sensitive genus-specific antigen (molecular weight 11,000) of Chlamydia spp. Nonfat dry milk was the most efficient additive at suppressing the fluorescent background and was included in the antibody preparation. Fc-dependent binding of fluorescein-conjugated MAbs to protein A-containing Staphylococcus aureus was inhibited by addition of purified rabbit immunoglobulin. The Chlamydia Direct Specimen Test IF was compared with tissue culture isolation by using 309 genital specimens. The sensitivity and specificity were 77.4 and 98%, respectively.

Influence of dietary lipids on microsomal membranes from chick breast muscle

1. The effect of different dietary fat intake on the lipid composition and fluidity of microsomal membranes as well as in the enzymatic activity of the Ca2+-ATPase from chick breast muscle was investigated. 2. When a standard diet was supplemented with 10% sunflower seed oil, an increase in the relative amounts of unsaturated fatty acids and membrane fluidity and a decrease in the cholesterol content was observed. 3. The presence of 6% cholesterol in the diet does not modify the fatty acid composition and the fluidity of the membrane but increased, in a low extension, the cholesterol content. 4. The provision of the sunflower seed oil-rich diet supplemented with cholesterol just 48 hr before death promoted an increase in the relative amounts of unsaturated fatty acids and cholesterol content whereas the membrane fluidity decreased in a significant extent. 5. Despite that dietary lipids gave rise in some cases to changes in lipid composition and in the physical state of the microsomal membrane, neither the Ca2+ uptake capacity nor the ATPase activity were significantly affected.

An anti-human mu chain monoclonal antibody: use for detection of IgM antibodies to Toxoplasma gondii by reverse immunosorbent assay

A precipitating anti-human mu chain monoclonal antibody (designated Tibi 82 McAb) was produced by the cell fusion technique. This McAb (isotype: IgG1 kappa) reacted by radioimmunoassay with all 10 human IgM proteins tested. In contrast, no reactivity was observed with IgG, IgA, IgE, lambda and kappa chains. 19 S IgM proteins were precipitated by Tibi 82 McAb using the Ouchterlony method under standard conditions. Hence specificity of this McAb for the C mu 2 domain was characterized by inhibition of precipitin reactions using human IgM fragments. Despite its narrow specificity for the C mu 2 domain, such a McAb could be used for IgM capture in the detection of specific IgM to Toxoplasma gondii employing the IgM immunosorbent agglutination assay (IgM-ISAGA). Tibi 82 McAb was compared with 3 anti-human IgM polyclonal reagents in the routine analysis of 117 sera. With 2 of them, a correlation coefficient of 0.976 was obtained and Tibi 82 McAb was more sensitive than the third polyclonal reagent tested. The IgM-ISAGA technique was shown to be reproducible using Tibi 82 McAb and similar anti-human mu chain McAbs could permit the wider development of reverse immunosorbent methods for the detection of specific IgM in various infectious diseases.

An anti-human immunoglobulin M monoclonal antibody for detection of antibodies to Toxoplasma gondii

An anti-human mu-chain monoclonal antibody, Tibi 82, was produced and tested for specificity by radioimmunoassay. Its reliability in detecting IgM antibodies to Toxoplasma gondii was tested by two reverse immunosorbent methods (IgM-ISAGA and IgM-SPIHA) and the IgM fluorescent antibody test (IgM-IFA) on 400 sera. Whereas the results obtained with Tibi 82 and with two polyclonal reagents were highly correlated, the third commercial polyclonal reagent provided many false negative results. By standardizing IgM binding, Tibi 82 allowed the comparison of IgM-ISAGA with IgM-SPIHA on 100 sera: 17% of the sera tested showed discrepancies due to the different toxoplasma antigens used. Although Tibi 82 facilitated the reading of results and enhanced sensitivity and specificity of the double-sandwich IgM-IFA method, the latter was still less sensitive than IgM-ISAGA with Tibi 82. Tests with the monoclonal antibody were consistently superior to tests with polyclonal antibodies.

Influence of neonatal age on changes in fatty acid composition of microsomal lipids induced by long-term and short-term cholesterol feeding

Changes observed as a function of chick age in fatty acid composition of lipids from liver microsomes were considerably small, while the unsaturation index increased throughout postnatal development. Supplementation of the diet with 2% cholesterol from hatching produced a significant decrease in the levels of palmitic acid and a clear increase in those of polyunsaturated fatty acids. Maximum effects were attained on day 19 of treatment. Alterations in the fatty acid composition were more pronounced after short-term (48 h) cholesterol feeding. Administration for 48 h of a standard diet to chicks fed a cholesterol diet for 10 days from hatching restored the levels of fatty acids to those of the controls. However, when cholesterol feeding was prolonged for 24 days from hatching, no effect was found after the same treatment. Suppression of the cholesterol diet for 48 h in animals cholesterol fed for 48 h had no effect in 12-day-old chicks while the change to a standard diet produced a reversion of the effect of cholesterol feeding in 26-day-old animals.