RESUMEN

PURPOSE: To compare the pattern of gene-specific involvement and the spectrum of variants observed in prenatal and postnatal (mean ± SD, 8.9 ± 9.4 years) cohorts tested for Noonan syndrome and related conditions. METHODS: Outcomes of sequencing panel testing were compared between prenatal (n = 845) and postnatal (n = 409) cohorts. RESULTS: PTPN11 and SOS1 harbored the majority of observed variants in both prenatal and postnatal cohorts, and BRAF, HRAS, KRAS, MAP2K1, MAP2K2, RAF1, and SHOC2 had similarities in their pattern of involvement in both cohorts. PTPN11 was the largest contributor of pathogenic variants and had the lowest frequency of variants of uncertain significance (VUS). SOS1 had the highest VUS frequency in both cohorts. The overall VUS frequency was twice as high in prenatal specimens (58.1 vs. 29.3%). PTPN11 and SOS1 had a 1.5-fold higher VUS frequency in the prenatal cohort (10.7 vs. 7.4% and 95 vs. 61.1%, respectively). The diagnostic yield was 3.7% for prenatal samples, with a higher yield of 12.3% in fetuses with cystic hygroma as a sole finding, and 21.3% for postnatal. CONCLUSION: Comparison of prenatal versus postnatal specimens demonstrates that the pattern of specific gene involvement is similar, whereas the classification spectrum of observed variants differs considerably.

Asunto(s)

RESUMEN

The original version of this Article contained an error in the spelling of the author N. T. Leach, which was incorrectly given as N. L. Leach. This has been corrected in both the PDF and HTML versions of the Article.

RESUMEN

While most human T cells express the CD28 costimulatory molecule constitutively, it is well known that age, inflammation, and viral infection can drive the generation of CD28null T cells. In vitro studies have demonstrated that CD28null cell effector function is not impacted by the presence of the CD28 costimulation blocker belatacept. As such, a prevailing hypothesis suggests that CD28null cells may precipitate costimulation blockade-resistant rejection. However, CD28+ cells possess more proliferative and multifunctional capacity, factors that may increase their ability to successfully mediate rejection. Here, we performed a retrospective immunophenotypic analysis of adult renal transplant recipients who experienced acute rejection on belatacept treatment as compared to those who did not. Intriguingly, our findings suggest that patients possessing higher frequency of CD28+ CD4+ TEM prior to transplant were more likely to experience acute rejection following treatment with a belatacept-based immunosuppressive regimen. Mechanistically, CD28+ CD4+ TEM contained significantly more IL-2 producers. In contrast, CD28null CD4+ TEM isolated from stable belatacept-treated patients exhibited higher expression of the 2B4 coinhibitory molecule as compared to those isolated from patients who rejected. These data raise the possibility that pretransplant frequencies of CD28+ CD4+ TEM could be used as a biomarker to predict risk of rejection following treatment with belatacept.

Asunto(s)

RESUMEN

Recently, newer therapies have been designed to more specifically target rejection in an effort to improve efficacy and limit unwanted toxicity. Belatacept, a CD28-CD80/86 specific reagent, is associated with superior patient survival and graft function compared with traditional therapy, but its adoption as a mainstay immunosuppressive therapy has been tempered by increased rejection rates. It is essential that the underlying mechanisms associated with this rejection be elucidated before belatacept is more widely used. To that end, we designed a study in a nonhuman primate kidney transplant model where animals were treated with either a belatacept- or a tacrolimus-based immunosuppressive regimen. Interestingly, we found that elevated pretransplant frequencies of CD28+ CD8+ TEMRA cells are associated with rejection on belatacept but not tacrolimus treatment. Further analysis showed that the CD28+ CD8+ TEMRA cells rapidly lose CD28 expression after transplant in those animals that go on to reject with the allograft infiltrate being predominantly CD28- . These data suggest that CD28+ memory T cells may be resistant to belatacept, capable of further differentiation including loss of CD28 expression while maintaining effector function. The unique signaling requirements of CD28+ memory T cells provide opportunities for the development of targeted therapies, which may synergize with belatacept to prevent costimulation-independent rejection.

Asunto(s)

RESUMEN

The advent of costimulation blockade provides the prospect for targeted therapy with improved graft survival in transplant patients. Perhaps the most effective costimulation blockade in experimental models is the use of reagents to block the CD40/CD154 pathway. Unfortunately, successful clinical translation of anti-CD154 therapy has not been achieved. In an attempt to develop an agent that is as effective as previous CD154 blocking antibodies but lacks the risk of thromboembolism, we evaluated the efficacy and safety of a novel anti-human CD154 domain antibody (dAb, BMS-986004). The anti-CD154 dAb effectively blocked CD40-CD154 interactions but lacked crystallizable fragment (Fc) binding activity and resultant platelet activation. In a nonhuman primate kidney transplant model, anti-CD154 dAb was safe and efficacious, significantly prolonging allograft survival without evidence of thromboembolism (Median survival time 103 days). The combination of anti-CD154 dAb and conventional immunosuppression synergized to effectively control allograft rejection (Median survival time 397 days). Furthermore, anti-CD154 dAb treatment increased the frequency of CD4+ CD25+ Foxp3+ regulatory T cells. This study demonstrates that the use of a novel anti-CD154 dAb that lacks Fc binding activity is safe without evidence of thromboembolism and is equally as potent as previous anti-CD154 agents at prolonging renal allograft survival in a nonhuman primate preclinical model.

Asunto(s)

RESUMEN

BACKGROUND AND OBJECTIVES: Fostamatinib is a spleen tyrosine kinase inhibitor that has been investigated as therapy for rheumatoid arthritis and immune thrombocytopenic purpura. The present studies assessed the potential for pharmacokinetic interaction between fostamatinib and the commonly prescribed medications oral contraceptive (OC), warfarin, and statins (rosuvastatin, simvastatin) in healthy subjects. METHODS: The OC study was a crossover study over two 28-day treatment periods (Microgynon(®) 30 plus placebo or fostamatinib). Concentrations of OC constituents (ethinyl estradiol/levonorgestrel) were measured. Effects on warfarin pharmacokinetics and pharmacodynamics were assessed (21-day study). Warfarin was administered on days 1 and 14, fostamatinib on days 8-20. The statin study was a two-period, fixed-sequence study of the effects of fostamatinib on exposure to rosuvastatin or simvastatin (single doses). Safety was assessed throughout. RESULTS: Fostamatinib co-administration with OC increased exposure to ethinyl estradiol [area under the plasma concentration-time curve at steady state (AUCss) 28% [confidence interval (CI 90%) 21-36]; maximum plasma concentration (Cmax) at steady state (Cmax,ss) 34% (CI 26-43)], but not levonorgestrel (AUCss 5%; Cmax,ss -3%), while exposure to luteinizing hormone and follicle-stimulating hormone decreased (≈ 20%). Fostamatinib did not affect the pharmacokinetics/pharmacodynamics of warfarin to a clinically relevant extent, but caused an upward trend in AUC for both R- and S-warfarin [18% (CI 13-23) and 13% (CI 7-19)]. Fostamatinib increased rosuvastatin AUC by 96% (CI 78-115) and Cmax by 88% (CI 69-110), and increased simvastatin acid AUC by 74% (CI 50-102) and Cmax by 83% (CI 57-113). CONCLUSION: Fostamatinib exhibits drug-drug interactions when co-administered with OC, simvastatin, or rosuvastatin, with the AUC of statins almost doubling. Fostamatinib did not exhibit a clinically relevant DDI on warfarin.

Asunto(s)

RESUMEN

Sedation for medical procedures is provided in a variety of clinical settings by medical personnel with differing levels of education and training. Although generally a safe practice, there is a degree of morbidity and mortality associated with sedation practice. Monitoring standards continue to be refined by professional societies with the goal of improving care. The depth of sedation should be monitored with clinical criteria. Processed electroencephalographic monitors currently do not contribute significantly to sedation care. Monitoring ventilation using pulse oximetry should be abandoned for more direct methods, such as capnography-transcutaneous carbon dioxide, respiratory acoustical and thoracic impedance monitoring could also play a role. Propofol has become widely utilized for sedation, although there are concerns about its margin of safety and synergistic interactions with other agents. Dexmedetomidine and propofol/ketamine also have utility. Patient-controlled sedation pumps and target-controlled infusion devices have been developed to improve patient care and satisfaction. A computer-assisted propofol sedation device to be used by non-anaesthesiologists has been approved in the USA by the Food and Drug Administration. More computer-assisted sedation delivery devices are likely to be developed, but their clinical utility is unclear.

Asunto(s)

RESUMEN

In late May 2013, collapse of mature watermelon plants (Citrullus lanatus L.) at first harvest occurred in several drip-irrigated commercial fields in the Coachella Valley, California. Above-ground symptoms consisted of chlorosis, wilting, and death of leaves starting at the crown and progressing rapidly towards the tip of vines. Structural roots of collapsed plants appeared healthy but feeder roots exhibited a brownish discoloration. Microscopic examination revealed that almost all epidermal cells of feeder roots contained either sporangia or resting spores of a fungus tentatively identified, based upon morphological characteristics, as Olpidium bornovanus (Sahtiy.) Karling. No other fungi or fungal-like organisms were microscopically observed in or isolated from structural roots, feeder roots, or vascular tissue of collapsed plants. Leaf, root, and peduncle samples from collapsed plants were tested for Melon necrotic spot virus (MNSV), a virus known to be transmitted by O. bornovanus, and Squash vein yellowing virus (SqVYV), a whitefly-transmitted ipomovirus known to cause watermelon vine decline (1). No MNSV was detected using previously described methods (3). No SqVYV was detected by testing total RNA from symptomatic plants (RNeasy Plant Mini Kit, Qiagen, Valencia, CA) with reverse transcription-PCR using previously described primers and methods (1,2). Genomic DNA was extracted from zoospores of the fungus which were obtained from a single-sporangial isolate maintained on watermelon seedlings. Analysis of ITS 1 and 2 gene sequences and a subsequent search in NCBI GenBank revealed a 99% identity to nucleotide sequences for O. bornovanus (Accession Nos. AB205215 and AB665758). To confirm Koch's postulates, roots of three 5-day-old watermelon seedlings were inoculated by exposure to zoospores (~1 × 105) in a beaker for 2 min and then transplanted into pots containing vermiculite. Pots were irrigated daily and incubated in a growth chamber (25°C, 12-h photoperiod). Controls consisted of non-inoculated watermelon seedlings. The experiment was repeated twice. Within 15 days of inoculation, all inoculated plants were stunted, and roots of stunted plants were brown and most root epidermal cells were filled with either sporangia or resting spores of O. bornovanus. Within 30 days of inoculation, 40 to 60% of the inoculated plants died in all three experiments. No other microorganisms were microscopically observed in or isolated from necrotic roots. Control plants remained symptomless over the duration of the study. Although O. bornovanus has been reported as a root pathogen of melons in greenhouse conditions (3), this is the first worldwide report of the fungus as a root pathogen of watermelons and its association with a late season vine decline in the field. Near-saturated soil conditions resulting from a daily irrigation regime during the latter part of the growing season apparently favored extensive root colonization by this indigenous and opportunistic zoosporic fungus, suggesting that growers should exercise care regarding the duration and frequency of irrigation events. References: (1) S. Adkins et al. Phytopathology 97:145, 2007. (2) S. Adkins et al. Plant Dis. 1119, 2008. (3) M. E. Stanghellini et al. Plant Dis. 94:163, 2010.

RESUMEN

OBJECTIVE: Several lines of evidence suggest that pathologic changes underlying Alzheimer disease (AD) begin years prior to the clinical expression of the disease, underscoring the need for studies of cognitively healthy adults to capture these early changes. The overall goal of the current study was to map the cortical distribution of ß-amyloid (Aß) in a healthy adult lifespan sample (aged 30-89), and to assess the relationship between elevated amyloid and cognitive performance across multiple domains. METHODS: A total of 137 well-screened and cognitively normal adults underwent Aß PET imaging with radiotracer (18)F-florbetapir. Aß load was estimated from 8 cortical regions. Participants were genotyped for APOE and tested for processing speed, working memory, fluid reasoning, episodic memory, and verbal ability. RESULTS: Aß deposition is distributed differentially across the cortex and progresses at varying rates with age across cortical brain regions. A subset of cognitively normal adults aged 60 and over show markedly elevated deposition, and also had a higher rate of APOE ε4 (38%) than nonelevated adults (19%). Aß burden was linked to poorer cognitive performance on measures of processing speed, working memory, and reasoning. CONCLUSIONS: Even in a highly selected lifespan sample of adults, Aß deposition is apparent in some adults and is influenced by APOE status. Greater amyloid burden was related to deleterious effects on cognition, suggesting that subtle cognitive changes accrue as amyloid progresses.

Asunto(s)

RESUMEN

AIM: To ascertain the effectiveness, tolerability, and safety of low-dose cyclosporine in the management of sight-threatening uveitis. MATERIALS AND METHODS: This was a retrospective clinical case series of patients using oral low-dose cyclosporine for the management of sight-threatening uveitis in the uvea clinic (UC). Patients receiving cyclosporine were identified from the clinic database. Main outcome measures were degree of intraocular inflammation, visual acuity and dose reduction of oral steroid for effectiveness and adverse symptoms, systemic hypertension, and raised serum creatinine for tolerability and safety. RESULTS: Intraocular inflammation was improved or stable in 97% of patients, visual acuity was improved or stable in 91%, and oral steroid dosage was reduced in 73% (by half or more in 51%). Adverse symptoms were almost universal, the commonest being peripheral paresthesia/burning in 70% and fatigue in 67%. Significant systemic hypertension developed in 27% and raised creatinine in 30%, necessitating dose reduction. Cyclosporine was discontinued in 35%, being intolerable in 20% and ineffective in 15%. CONCLUSIONS: Cyclosporine was found to be effective in reducing inflammation and protecting vision in sight-threatening uveitis. It was safe with proper monitoring, including in children. It had a significant toxicity profile and a high incidence of adverse symptoms which required close supervision, and a prompt dose reduction or drug exchange.

Asunto(s)

RESUMEN

Greenhouse studies document, for the first time, that Olpidium bornovanus, an obligate, holocarpic, root-inhabiting zoosporic fungus heretofore regarded as a nonpathogenic parasite, is a root pathogen. Significant browning of the roots and reductions in shoot and root growth were recorded within 28 days following inoculation of melons with the fungus. Amending the recirculating nutrient solution with either a nonionic surfactant (Agral 90) or a strobilurin fungicide (azoxystrobin) resulted in efficacious management of the disease caused by the fungus.

RESUMEN

A well-studied severe isolate of Citrus tristeza virus (CTV) known as SY568 has previously been shown to contain multiple variants of the virus which differ in their genetic and biological characters. Aphid transmission was used in an attempt to segregate some of these variants for further characterization. Resulting infections gave symptoms which varied from asymptomatic to more severe than the inoculum source. RNase protection assays (RPAs) were used to compare nine regions of the CTV genome and determine whether unique strains could be identified. Five aphid-transmitted subcultures, with fingerprints that were different from those of the inoculum sources in at least one genomic area, were then cloned, sequenced, and compared with known isolates. An asymptomatic strain was shown to be different in every area of the CTV genome when examined by RPA and sequencing of selected regions. Mixed-infection studies using graft transmission of the asymptomatic subculture and two of the more severe aphid-transmitted subcultures showed that the mild strain was not able to compete well when in the presence of any of the severe variants tested, and its titer was significantly reduced from that seen in single infection. The mild strain and a selected severe strain were singly graft inoculated into five different citrus hosts (sweet orange, grapefruit, sour orange, lemon, and lime), where they maintained their distinct biological and genetic characteristics.

Asunto(s)

Asunto(s)

RESUMEN

The prospect of using cell-based interventions (CBIs) to treat neurological conditions raises several important ethical and policy questions. In this target article, we focus on issues related to the unique constellation of traits that characterize CBIs targeted at the central nervous system. In particular, there is at least a theoretical prospect that these cells will alter the recipients' cognition, mood, and behavior-brain functions that are central to our concept of the self. The potential for such changes, although perhaps remote, is cause for concern and careful ethical analysis. Both to enable better informed consent in the future and as an end in itself, we argue that early human trials of CBIs for neurological conditions must monitor subjects for changes in cognition, mood, and behavior; further, we recommend concrete steps for that monitoring. Such steps will help better characterize the potential risks and benefits of CBIs as they are tested and potentially used for treatment.

Asunto(s)

Asunto(s)

RESUMEN

BACKGROUND: Attempts to translate basic stem cell research into treatments for neurologic diseases and injury are well under way. With a clinical trial for one such treatment approved and in progress in the United States, and additional proposals under review, we must begin to address the ethical issues raised by such early forays into human clinical trials for cell-based interventions for neurologic conditions. METHODS: An interdisciplinary working group composed of experts in neuroscience, cell biology, bioethics, law, and transplantation, along with leading disease researchers, was convened twice over 2 years to identify and deliberate on the scientific and ethical issues raised by the transition from preclinical to clinical research of cell-based interventions for neurologic conditions. RESULTS: While the relevant ethical issues are in many respects standard challenges of human subjects research, they are heightened in complexity by the novelty of the science, the focus on the CNS, and the political climate in which the science is proceeding. CONCLUSIONS: Distinctive challenges confronting US scientists, administrators, institutional review boards, stem cell research oversight committees, and others who will need to make decisions about work involving stem cells and their derivatives and evaluate the ethics of early human trials include evaluating the risks, safety, and benefits of these trials, determining and evaluating cell line provenance, and determining inclusion criteria, informed consent, and the ethics of conducting early human trials in the public spotlight. Further study and deliberation by stakeholders is required to move toward professional and institutional policies and practices governing this research.

Asunto(s)

Asunto(s)

RESUMEN

BACKGROUND: Centralized spirometry may significantly improve quality of spirometry and reduce variability of this outcome measure in clinical trials in cystic fibrosis (CF). METHODS: Spirometry was performed during the phase 2 randomized, placebo-controlled, double-blind clinical trial of denufosol in patients with mild to moderate CF using American Thoracic Society guidelines. Uniform spirometers were used with electronic data transmission of all the data to a reading center. Spirometry was evaluated for quality by a central reader based on start of test, cough during the test, and evidence of a plateau. RESULTS: A total of 1418 spirometry values were assessed in 89 subjects during the trial. In only 5 instances did the central reading center need to give feedback to sites regarding the quality of spirometry. The study site data matched the central reading center's data for all but 78 (6%) spirometry values in 33 patients. Many of these differences were small with only 35 (3%) values differing by more than 50 mL in 26 patients. CONCLUSION: Spirometry in this clinical trial was of high quality with low rate of significant centralized over-read.

Asunto(s)

RESUMEN

Polyvinyl alcohol (PVA) hydrogels blended with chitosan or other biological macromolecules have shown promise for cell culture and tissue engineering. This study investigates the attachment and growth of bovine aortic endothelial (BAEC) and smooth muscle cells (BASMC) on the PVA hydrogels modified with water soluble and water insoluble chitosan. Cell adhesion on the surface of the membranes was examined by phase contrast microscopy while cell morphologies were studied using immunocytochemistry staining with EC and SMC specific biomarkers (F-actin and alpha actin respectively). Cells cultured on 6% PVA, 0.4% chitosan (water soluble and insoluble) hydrogel membranes displayed excellent adhesion and spreading characteristics, in addition to negligible cell structural morphological changes in comparison to a polystyrene control. Similar vascular cell adhesion features were apparent on PVA membranes blended with water-soluble and -insoluble chitosan. Fluorescent activated cell sorter (FACS) analysis was used to determine BAEC and BASMC proliferation and cell viability. Apoptotic levels in BAEC after 7 days were 12.8% +/- 2.5% on the PVA- chitosan WS-1 membrane and 10.1% +/- 1.5% on the control well (n = 3) while comparable results were also noted for BASMC. Equivalent proliferative activity was apparent for BAEC on the control and PVA-chitosan membrane after 7 days, while BASMC showed increased proliferative activity on the membranes. These results indicate that the PVA-chitosan blended hydrogel membranes show promise for cell culture and tissue engineering applications.

Asunto(s)

RESUMEN

Between June 2006 and July 2007, ornamental plant samples were collected from four counties in California (Riverside, Sacramento, San Diego, and Santa Barbara) and tested for the presence of Angelonia flower break virus (AnFBV) using ELISA (Agdia, Inc., Elkhart, IN). Tissue samples were from propagation facilities or wholesale outlets except those from Riverside County, which were from retail stores. Thirteen positive samples were found in three varieties each of Angelonia and Nemesia spp. and seven varieties of Verbena spp., with at least one positive from each county. Foliar symptoms ranged from asymptomatic to a mild mosaic with distinct flower breaking in the Angelonia spp. Results were confirmed by reverse transcription (RT)-PCR of the coat protein gene (1) and the 1,172-bp amplicons were sequenced. Viral isolates from the three varieties of the Angelonia spp. had 98 to 99% nucleotide similarity and 99 to 100% amino acid identity to the Maryland strain of AnFBV (1; GenBank Accession No. DQ221212), with 91 to 92% nucleotide similarity and 96 to 97% amino acid identity to the Israel and Florida strains (GenBank Accession Nos. DQ223771 and DQ219415). All viral isolates from the Nemesia and Verbena spp. plants had nucleotide similarities of 96 to 98% and 98% amino acid identity to the Israel and Florida strains, with 91 to 92% nucleotide similarity to the Maryland strain. AnFBV has been previously reported in Angelonia and Verbena spp. among other hosts (1,2), but not in Nemesia spp. and not in California. This recently described carmovirus appears to be well established in the state in a variety of ornamental plant species. References: (1) S. Adkins et al. Phytopathology 96:460, 2006. (2) F. Assis-Filho et al. Plant Dis. 90:1115, 2006.