Controlled growth of ultrasmall Cu2O clusters on TiO2nanoparticles by atmospheric-pressure atomic layer deposition for enhanced photocatalytic activity.

This work presents a gas-phase approach for the synthesis of Cu2O/TiO2powder-based photocatalysts using atomic layer deposition (ALD). The process is carried out in a fluidized bed reactor working at atmospheric pressure using (trimethylvinylsilyl)-hexafluoroacetulacetonate copper(I) as the Cu-precursor and H2O vapor as the oxidizer. The saturating regime of the chemical reactions and the linear growth of ALD are achieved. In combination with the unsaturated regime, the ALD approach enables the deposition of ultrasmall Cu2O clusters with average diameters in the range of 1.3-2.0 nm, narrow particle size distributions and tunable Cu2O loadings on P25 TiO2nanoparticles. The photocatalytic performance of Cu2O/TiO2photocatalysts is investigated by the degradation of organic dyes, including Rhodamine B (RhB), methyl orange, and methylene blue; the results demonstrate that the surface modification of TiO2nanoparticles by Cu2O nanoclusters significantly enhances the photocatalytic activity of TiO2. This is attributed to the efficient charge transfer between Cu2O and TiO2that reduces the charge recombination. The photocatalytic reaction mechanism is further investigated for the degradation of RhB, revealing the dominating role of holes, which contribute to both direct hole oxidation and indirect oxidation (i.e. via the formation of hydroxyl radicals). Our approach provides a fast, scalable and efficient process to deposit ultrasmall Cu2O clusters in a controllable fashion for surface engineering and modification.

Pediatric Liver Transplantation: Then and Now.

This paper reviews the past 50 years of liver transplantation in children from the perspective of patient demographics, perioperative patient management, surgical techniques, immunosuppression and patient outcomes.

Red Blood Cell Transfusion in Pediatric Orthotopic Liver Transplantation: What a Difference a Few Decades Make.

BACKGROUND: Liver transplantation in children is often associated with coagulopathy and significant blood loss. Available data are limited. In this observational retrospective study, we assessed transfusion practices in pediatric patients undergoing liver transplantation at a single institution over the course of 9 years. METHODS: Data were retrospectively collected from patient medical records at the Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center. All patients who underwent liver transplantation from January 2008 to June 2017 were included. Primary and secondary outcomes were volume of red blood cells (RBCs) transfused and mortality, respectively. RESULTS: From January 2008 to June 2017, there were 278 liver transplants in 271 patients. The number of primary transplants were 259, second retransplants 15, and third retransplants 4. Average age at transplantation was 6.9 years. Biliary atresia, maple syrup urine disease, urea cycle defect, and liver tumor were the leading indications accounting for 66 (23.7%), 45 (16.2%), 24 (8.6%), and 23 (8.3%) of transplants, respectively. Seventy-six cases (27.3%) did not require RBC transfusions. Among those transfused, 181 (89.6%) of the cases required <1 blood volume (BV). The median BV transfused among all cases was 0.21 (range, 0-9; Q1, 0; Q3, 0.45). There is a trend toward higher volume transfusions among infants (median, 0.46 BV) compared to children >12 months of age (0.12 BV). By diagnosis, the group requiring the highest median volume transfusion was patients with total parenteral nutrition-related liver failure (3.41 BV) followed by patients undergoing repeat transplants (0.6 BV). Comparison of primary versus repeat transplants shows a trend toward higher volume transfusions in third transplants (median, 2.71 BV), compared to second transplants (0.43 BV) and primary transplants (0.18 BV). Four of 271 patients (1.5%) died during admission involving liver transplantation. Nine of 271 patients (3.3%) died subsequently. Total mortality was 4.8%. CONCLUSIONS: In contrast to historically reported trends, evaluation of current transfusion practices reveals that most patients undergoing liver transplantation receive <1 BV of packed RBCs. More than 1 in 4 transplantations require no transfusion at all. Risk factors for greater transfusion need include younger age, total parenteral nutrition-related liver failure, and repeat transplantation.

Variation in out-of-hospital death among palliative care inpatients across public hospitals in New South Wales, Australia.

BACKGROUND: Place of death is an important indicator in palliative care, as out-of-hospital death is often preferred by patients and is less costly for the healthcare system. AIM: To examine variation and contributing factors in out-of-hospital death after receiving palliative care in hospital to inform improvement in transition of care between hospitals and communities. METHODS: Using hospital linked data (July 2010, June 2015) we followed individuals aged 50 or older who received palliative care in hospital and within 3 months to death who were last admitted to a public acute-care hospital in New South Wales, Australia (73 hospitals). RESULTS: Among 25 359 palliative care inpatients, 3677 (14%) died out of hospital. The out-of-hospital death rate was lower for younger patients, males and those living in the most deprived areas; it was higher for cancer patients and those who received palliative care before their last admission. Hospital size, location and availability of hospice care unit were not influential. Across hospitals, the median crude rate of out-of-hospital death was 14% (interquartile range 10-19%). The contributing factors explained 19% of the variation, resulting in a rate difference of 44% between hospitals with high versus low rates; 25% of hospitals had a higher and 14% had a lower than average adjusted out-of-hospital death rate. CONCLUSION: The majority of patients who received palliative care in hospital stayed in hospital until death. The variation in out-of-hospital death across hospitals was considerable and mostly remained unexplained. This variability warrants investigation into transition of palliative care between hospitals and communities to inform interventions.

Application of a solvent-free solid injection technique coupled with GC-MS for discrimination between the secondary metabolites of wild and cultivated South Korean medicinal foods.

Solvent-free solid injection was applied to differentiate between wild and cultivated South Korean medicinal foods, including dureup (Aralia elata), deodeok (Codonopsis lanceolata) and doraji (Platycodon grandiflorus). A number of compounds were identified in wild and cultivated dureup (53 and 46), deodeok (47 and 51) and doraji (43 and 38). Secondary metabolites, including butanal,2-methyl-, ß-caryophyllene, neoclovene, α-humulene, γ-curcumene, ß-bisabolene, and phytol, were identified in dureup with significantly (P < 0.05) different amounts between both types. In deodeok, squalene and other main components such as acetic acid, methyl ester, furan-methyl-furfural, 2-furan-methanol, and 5-methyl-furfural, were statistically different between the two types. Doraji has significantly different compounds such as furfural, 5-methyl-furfural, 2-methoxy-phenol, 2-methoxy-4-(1-propenyl)-phenol, and 1-(4-hydroxy-3-methoxyphenyl)-2-propanone. Although we failed to confirm the key compounds, a new compound, namely desaspidinol, was synthesized for the first time and its retention index determined under the experimental conditions. This solventless, easy technique can be used as a simple way to discriminate between wild and cultivated types of medicinal plants via identification of volatile markers or specific fingerprints.

The disappearance rate and risk assessment of thiacloprid residues in Asian pear using liquid chromatography confirmed with tandem mass spectrometry.

This study was undertaken to quantify the residue levels and propose the dissipation kinetics of thiacloprid formulated as suspension concentrate in field-incurred Asian pears grown under two different open-field conditions. Samples were extracted with 20% distilled water in acetonitrile; partitioned with brine water and dichloromethane; and purified with a Florisil solid phase extraction cartridge. The analyte was identified with an LC ultraviolet detector, and field-incurred samples were confirmed using LC-MS/MS. The calibration curve was linear over the range 0.05-5.0 mg/L with a satisfactory coefficient of determination (R2 = 0.9994). The limits of detection and limits of quantification (LOQ) were 0.003 and 0.01 mg/kg, respectively. The recovery rate fortified to blank samples at LOQ, 10× LOQ, and the maximum residue limit (MRL) were between 73.7 and 86.2% with relative standard deviation ≤9.0%. The residual concentrations at both sites were considerably lower than the MRL (0.7 mg/kg) set by the Korean Ministry of Food Drug Safety, with biological half-lives of 5.0 and 7.4 days, for sites 1 and 2, respectively. From the pre-harvest residue limit curve, it was predicted that if the residues were <1.13 or 1.40 mg/kg 10 days before harvest, the residue level would be lower than the MRL during harvest. Risk assessment on day 0 showed an acceptable daily intake (%) of 13.0% and 11.0% for sites 1 and site 2, respectively, which indicates that the residual amounts are not hazardous to the Korean population.

Various extraction methods for detection of bistrifluron residues in Asian pear using high-performance liquid chromatography: application to dissipation patterns under open-field conditions.

The present study was carried out to develop an analytical method for the detection and quantification of bistrifluron, a benzoylphenylurea compound, in pear using high-performance liquid chromatography with UV detection. Samples were extracted using conventional, AOAC and EN quick, easy, cheap, effective, rugged and safe 'QuEChERS' methods. As expected, conventional and EN-QuEChERS methods gave higher recoveries than AOAC. In addition, interference around the analyte retention time was observed in the conventional method. Thus, the EN-QuEChERS method was selected and validated by studying various parameters, including linearity, limit of detection, limit of quantification (LOQ), recovery and precision. Linearity was excellent, with a correlation coefficient of 0.9998. Recovery rates at three spiking levels (0.05, 0.2 and 1 mg/kg) ranged from 73.76 to 98.66%. Intra- and inter-day precisions, expressed as relative standard deviations, were <6%. The LOQ of 0.05 mg/kg was considerably lower than the maximum residue limit (1 mg/kg) set by the Korean Ministry of Food and Drug Safety. The developed method was successfully applied to open-field pear samples, in which the target analyte was slowly dissipated (55% decline) over 14 days with a half-life of 10.19 days. Notably, the residue levels throughout the period of sample collection (14 days) were lower than the maximum residue limit, indicating that the residue was not hazardous for consumers. Copyright © 2016 John Wiley & Sons, Ltd.

Residue level and dissipation pattern of lepimectin in shallots using high-performance liquid chromatography coupled with photodiode array detection.

Lepimectin, as an emulsifiable concentrate, was sprayed on shallots at the recommended dose rate (10 mL/20 L) to determine its residue levels, dissipation pattern, pre-harvest residue limits (PHRLs), and health risk. Samples were randomly collected over 10 days, extracted with acetonitrile, purified using an amino solid-phase extraction (NH2 -SPE) cartridge and analyzed using a high-performance liquid chromatography-photodiode array detection method. Field-incurred samples were confirmed using ultra-performance liquid chromatography-tandem mass spectrometry. The linearity was excellent, with a determination coefficient (R2 ) of ≥0.9991. The recoveries at two spiking levels (0.2 and 1.0 mg/kg) ranged from 84.49 to 87.64% with relative standard deviations of ≤7.04%. The developed method was applied to field samples grown in separate greenhouses, one located in Naju and one in Muan, in the Republic of Korea. The dissipation pattern was described by first-order kinetics with half-lives of 1.9 (Naju) and 1.7 days (Muan). The PHRL curves indicated that, if the lepimectin residues are <0.18 (Naju) and <0.13 mg/kg (Muan) 5 days before harvest, the residue levels will be lower than the maximum residue limit (0.05 mg/kg) upon harvesting. The risk assessment data indicated that lepimectin is safe for use in the cultivation of shallots, with no risk of detrimental effects to the consumer.

Effects of light shading and climatic conditions on the metabolic behavior of flonicamid in red bell pepper.

The degradation behavior of flonicamid and its metabolites (4-trifluoromethylnicotinic acid (TFNA) and N-(4-trifluoromethylnicotinoyl) glycine (TFNG)) was evaluated in red bell pepper over a period of 90 days under glass house conditions, including high temperature, low and high humidity, and in a vinyl house covered with high density polyethylene light shade covering film (35 and 75%). Flonicamid (10% active ingredient) was applied (via foliar application) to all fruits, including those groups grown under normal conditions (glass house) or under no shade cover (vinyl house). Samples were extracted using a Quick, Easy, Cheap, Effective, Rugged, and Safe "QuEChERS" method and analyzed using liquid chromatography-tandem mass spectrometry (LC/MS/MS). The method performance, including linearity, recovery, limits of detection (LOD), and quantitation (LOQ), was satisfactory. Throughout the experimental period, the residual levels of flonicamid and TFNG were not uniform, whereas that of TFNA remained constant. The total sum of the residues (flonicamid and its metabolites) was higher in the vinyl house with shade cover than in the glass house, under various conditions. The total residues were significantly higher when the treatment was applied under high light shade (75%). The flonicamid half-life decreased from 47.2 days (under normal conditions) to 28.4 days (at high temperatures) in the glass house, while it increased from 47.9 days (no shade cover) to 66 days (75% light shading) in the vinyl house. High humidity leads to decreases in the total sum of flonicamid residues in red bell pepper grown in a glass house, because it leads to an increase in the rate of water loss, which in turn accelerates the volatilization of the pesticide. For safety reasons, it is advisable to grow red bell pepper under glass house conditions because of the effects of solar radiation, which increases the rate of flonicamid degradation into its metabolites.

Targeting Notch, a key pathway for ovarian cancer stem cells, sensitizes tumors to platinum therapy.

Chemoresistance to platinum therapy is a major obstacle that needs to be overcome in the treatment of ovarian cancer patients. The high rates and patterns of therapeutic failure seen in patients are consistent with a steady accumulation of drug-resistant cancer stem cells (CSCs). This study demonstrates that the Notch signaling pathway and Notch3 in particular are critical for the regulation of CSCs and tumor resistance to platinum. We show that Notch3 overexpression in tumor cells results in expansion of CSCs and increased platinum chemoresistance. In contrast, γ-secretase inhibitor (GSI), a Notch pathway inhibitor, depletes CSCs and increases tumor sensitivity to platinum. Similarly, a Notch3 siRNA knockdown increases the response to platinum therapy, further demonstrating that modulation of tumor chemosensitivity by GSI is Notch specific. Most importantly, the cisplatin/GSI combination is the only treatment that effectively eliminates both CSCs and the bulk of tumor cells, indicating that a dual combination targeting both populations is needed for tumor eradication. In addition, we found that the cisplatin/GSI combination therapy has a synergistic cytotoxic effect in Notch-dependent tumor cells by enhancing the DNA-damage response, G(2)/M cell-cycle arrest, and apoptosis. Based on these results, we conclude that targeting the Notch pathway could significantly increase tumor sensitivity to platinum therapy. Our study suggests important clinical applications for targeting Notch as part of novel treatment strategies upon diagnosis of ovarian cancer and at recurrence. Both platinum-resistant and platinum-sensitive relapses may benefit from such an approach as clinical data suggest that all relapses after platinum therapy are increasingly platinum resistant.

Genetic diversity of the endemic flat-needle pine Pinus krempfii (Pinaceae) from Vietnam revealed by SSR markers.

Pinus krempfii Lecomte (Pinaceae) is an endemic tree to Vietnam with restricted habitats at higher altitudes in the highlands. In this study, genetic variation of four populations of P. krempfii was assessed using 17 microsatellite markers (single sequence repeats). Of these 17 markers, eight were polymorphic, and among the 42 putative alleles amplified, 32 were polymorphic (accounting for 76.19%). The Cong Troi population was found to be the most genetically diverse (Shannon's information index, I = 0.415, and percentage of polymorphic bands, PPB = 52.95%), whereas the Hon Giao population was found to have the lowest diversity (I = 0.330 and PPB = 47.06%). The genetic diversity at species level was also estimated (I = 0.414, PPB = 76.19%). Molecular variance was found to be low among populations (11.94%) and high among individuals within the populations (88.06%). Private alleles were not detected in the Hon Giao population. The Yang Ly population had a positive FIS (inbreeding coefficient) value of 0.071, while the three remaining populations had negative values (-0.116 for Cong Troi, -0.316 for Chu Yang Sin, and -0.350 for Hon Giao). The results obtained show an excess of homozygosity in the Yang Ly population, and also suggest a deficiency of heterozygosity for this population. Several approaches and measures of conservation for P. krempfii are discussed and proposed.

Estimated morbidity and mortality in adolescents and young adults diagnosed with Type 2 diabetes mellitus.

AIMS: To estimate remaining life expectancy (RLE), quality-adjusted life expectancy (QALE), causes of death and lifetime cumulative incidence of microvascular/macrovascular complications of diabetes for youths diagnosed with Type 2 diabetes. METHODS: A Markov-like computer model simulated the life course for a hypothetical cohort of adolescents/young adults in the USA, aged 15-24 years, newly diagnosed with Type 2 diabetes following either conventional or intensive treatment based on the UK Prospective Diabetes Study. Outcomes included RLE, discounted QALE in quality-adjusted life years (QALYs), cumulative incidence of microvascular/macrovascular complications and causes of death. RESULTS: Compared with a mean RLE of 58.6 years for a 20-year-old in the USA without diabetes, conventional treatment produced an average RLE of 43.09 years and 22.44 discounted QALYs. Intensive treatment afforded an incremental 0.98 years and 0.44 discounted QALYs. Intensive treatment led to lower lifetime cumulative incidence of all microvascular complications and lower mortality from microvascular complications (e.g. end-stage renal disease (ESRD) death 19.4% vs. 25.2%). Approximately 5% with both treatments had ESRD within 25 years. Lifetime cumulative incidence of coronary heart disease (CHD) increased with longer RLE and greater severity of CHD risk factors. Incorporating disutility (loss in health-related quality of life) of intensive treatment resulted in net loss of QALYs. CONCLUSIONS: Adolescents/young adults with Type 2 diabetes lose approximately 15 years from average RLE and may experience severe, chronic complications of Type 2 diabetes by their 40s. The net clinical benefit of intensive treatment may be sensitive to preferences for treatment. A comprehensive management plan that includes early and aggressive control of cardiovascular risk factors is likely needed to reduce lifetime risk of CHD.

Reducing the proportion of stillborn babies classified as unexplained in Vietnam by application of the PSANZ clinical practice guideline.

BACKGROUND: Over 2.6 million babies are stillborn every year mostly in low- and middle-income countries, where cause of death remains often unexplained. AIM: To determine the applicability and utility of the Perinatal Society of Australia and New Zealand (PSANZ) Clinical Practice Guideline (CPG) for Perinatal Mortality in reducing the proportion of unexplained stillbirths in a hospital setting in Vietnam. METHODS: An analytic cross-sectional study of stillborn babies born at a major maternity facility in Vietnam. Maternal history, external physical examination of the baby and placental macroscopic examination were performed. Two experienced classifiers independently assigned PSANZ perinatal death classification (PDC). This was compared to cause of death documented in the hospital records. RESULTS: 107 stillborn babies were born to 105 mothers. The proportion of stillborn babies classified as unexplained was reduced from 52.3 to 24.3% (P < 0.01) using the PSANZ-PDC system. Causes of death were congenital abnormalities (35.6%), hypertension (8.4%), fetal growth restriction (8.4%), specific perinatal conditions (8.4%), spontaneous preterm (6.5%), maternal conditions (5.6%) and antepartum haemorrhage (3.7%). CONCLUSIONS: Application of the PSANZ-CPG and stillbirth classification system is effective and feasible in a low-income country facility setting and resulted in a reduction in the number of babies classified as unexplained stillbirth in Vietnam.

TORC1 kinase and the S-phase cyclin Clb5 collaborate to promote mitotic spindle assembly and DNA replication in S. cerevisiae.

The Target of Rapamycin complex 1 (TORC1) is a central regulator of eukaryotic cell growth that is inhibited by the drug rapamycin. In the budding yeast Saccharomyces cerevisiae, translational defects associated with TORC1 inactivation inhibit cell cycle progression at an early stage in G1, but little is known about the possible roles for TORC1 later in the cell cycle. We investigated the rapamycin-hypersensitivity phenotype of cells lacking the S phase cyclin Clb5 (clb5Δ) as a basis for uncovering novel connections between TORC1 and the cell cycle regulatory machinery. Dosage suppression experiments suggested that the clb5Δ rapamycin hypersensitivity reflects a unique Clb5-associated cyclin-dependent kinase (CDK) function that cannot be performed by mitotic cyclins and that also involves motor proteins, particularly the kinesin-like protein Kip3. Synchronized cell experiments revealed rapamycin-induced defects in pre-anaphase spindle assembly and S phase progression that were more severe in clb5Δ than in wild-type cells but no apparent activation of Rad53-dependent checkpoint pathways. Some rapamycin-treated cells had aberrant spindle morphologies, but rapamycin did not cause gross defects in the microtubule cytoskeleton. We propose a model in which TORC1 and Clb5/CDK act coordinately to promote both spindle assembly via a pathway involving Kip3 and S phase progression.

Variation in Hospital Use at the End of Life Among New South Wales Residents Who Died in Hospital or Soon After Discharge.

Objective: Hospital use increases in the last 3 months of life. We aimed to examine its association with where people live and its variation across a large health jurisdiction. Methods: We studied a number of emergency department presentations and days spent in hospital, and in-hospital deaths among decedents who were hospitalized within 30 days of death across 153 areas in New South Wales (NSW), Australia, during 2010-2015. Results: Decedents' demographics and health status were associated with hospital use. Primary care and aged care supply had no or minimal influence, as opposed to the varying effects of areal factors-socioeconomic status, remoteness, and distance to hospital last admitted. Overall, there was an approximate 20% difference in hospital use by decedents across areas. In all, 18% to 57% of areas had hospital use that differed from the average. Discussion: The observed disparity can inform targeted local efforts to strengthen the use of community care services and reduce the burden of end-of-life care on hospitals.

Variations in hospital inpatient palliative care service use: a retrospective cohort study.

OBJECTIVE: Use of palliative care in hospitals for people at end of life varies. We examined rate and time of in-hospital palliative care use and associated interhospital variations. METHODS: We used admissions from all hospitals in New South Wales, Australia, within a 12-month period, for a cohort of adults who died in 73 public acute care hospitals between July 2010 and June 2014. Receiving palliative care and its timing were based on recorded use. RESULTS: Among 90 696 adults who died, 27% received palliative care, and the care was initiated 7.6 days (mean; SD: 3.3 days) before death. Over the 5-year period, the palliative care rate rose by 58%, varying extent across chronic conditions. The duration of palliative care before death declined by 7%. Patient (demographics, morbidities and service use) and hospital factors (size, location and availability of palliative care unit) explained half of the interhospital variation in outcomes: adjusted IQR in rate and duration of palliative care among hospitals were 23%-39% and 5.2-8.7 days, respectively. Hospitals with higher rates often initiated palliative care earlier (correlation: 0.39; p<0.01). CONCLUSION: Despite an increase over time in the palliative care rate, its initiation was late and of brief duration. Palliative care use was associated with patient and hospital characteristics; however, half of the between hospital variation remained unexplained. The observed suboptimal practices and variability indicate the need for expanded and standardised use of palliative care supported by assessment tools, service enhancement and protocols.

Molecular characterization of human Ro/SS-A antigen. Amino terminal sequence of the protein moiety of human Ro/SS-A antigen and immunological activity of a corresponding synthetic peptide.

The Ro/SS-A antigen was purified from an Epstein-Barr virus-transformed human B lymphoblastoid cell line. The amino terminal amino acid sequence of the 60-kD polypeptide bearing this antigenic epitope was determined to be: (formula; see text) A peptide composed of residue 6-19 was synthesized by the solid-phase method. Immunodiffusion-defined monospecific autoimmune sera to Ro/SS-A reacted with this synthetic peptide in ELISA, whereas autoantibodies with other specificities such as anti-La/SS-B and anti-Sm, as well as normal human sera, were not reactive. In addition, rabbit anti-peptide 6-19 antisera reacted specifically with native human Ro/SS-A antigen in ELISA. Furthermore, this synthetic peptide inhibited the binding of rabbit anti-peptide antiserum to native human Ro/SS-A. An additional synthetic peptide corresponding to residues 7-24 partially inhibited the binding of a patient anti-Ro/SS-A serum to native Ro/SS-A. These results suggest that the amino terminal portion of the molecule represents a major epitope of Ro/SS-A. The determination of the amino acid sequence of Ro/SS-A and the availability of synthetic peptide(s) bearing this antigen should provide additional approaches to further characterize the autoimmune response to this antigen.

A human Ro/SS-A autoantigen is the homologue of calreticulin and is highly homologous with onchocercal RAL-1 antigen and an aplysia "memory molecule".

The Ro/SS-A (Ro) autoantigens consist of at least four immunologically distinct proteins which are recognized by autoantibodies typically found in sera from patients with primary Sjogren's syndrome and in subsets of patients with lupus erythematosus. We recently isolated a 1.9-kb human cDNA clone which encodes one of these Ro autoantigens. Synthetic oligonucleotides corresponding to the human Ro sequence were used to amplify the homologous gene from a murine B cell cDNA library using the polymerase chain reaction. The mouse cDNA-encoded amino acid sequence was found to be 94% homologous to the human Ro sequence and is 100% homologous to murine calreticulin, a high affinity calcium-binding protein which resides in the endoplasmic and sarcoplasmic reticulum. The amino acid sequence of rabbit calreticulin is 92% homologous to both murine calreticulin and human Ro. Onchocerca volvulus and Drosophila melanogaster also have molecules that are highly homologous to human Ro. In addition, human Ro has a molecular mass, isoelectric point, and significant amino acid sequence similar to the Aplysia californica snail neuronal protein 407. These homologies suggest that this Ro protein has a very basic cellular function(s) which may in part involve calcium binding.

Serological cross-reactivity between a human Ro/SS-A autoantigen (calreticulin) and the lambda Ral-1 antigen of Onchocerca volvulus.

We have cloned and sequenced a 46-kD Ro/SS-A autoantigen gene that is the human homologue of the calcium-binding protein, calreticulin. The sequence of this 46-kD Ro/SS-A protein (calreticulin) has significant homology to lambda Ral-1, a recombinant cDNA clone corresponding to a major antigen of the nematode, Onchocerca volvulus, the infectious agent of onchocerciasis. We therefore sought to determine whether antibodies produced by onchocerciasis patients might crossreact with the human 46-kD Ro/SS-A autoantigen (calreticulin). 20 of 22 sera from Liberian onchocerciasis patients who had no known evidence of autoimmune disease were found to contain antibodies that reacted with the 46-kD Ro/SS-A (calreticulin) by immunoblot analysis. Characteristic of sera reactive with Ro/SS-A antigens, some onchocerciasis sera also immunoprecipitated the Ro/SS-A-associated hY RNAs. In addition, a monoclonal antibody raised against O. volvulus organisms reacted to purified human WiL-2 cell 46 kD Ro/SS-A antigen (calreticulin) by ELISA. These results strongly suggest that onchocerciasis patients produce antibodies that crossreact with the 46-kD human Ro/SS-A autoantigen (calreticulin) and raise the possibility that infectious organisms such as O. volvulus might play a triggering or exacerbating role in the human Ro/SS-A autoimmune response.

Molecular cloning, expression, and chromosome 19 localization of a human Ro/SS-A autoantigen.

Ro/SS-A antibodies are found in a number of human autoimmune disorders including Sjogren's syndrome and several systemic lupus erythematosus-related disorders. These heterogeneous autoantibodies are known to recognize several distinct cellular antigens. With synthetic oligonucleotides corresponding to amino acid sequence information we have isolated a full-length cDNA clone which encodes a human Ro ribonucleoprotein autoantigen. The 1,890-base pair clone contains an open reading frame that encodes a 417-amino acid, 48-kD polypeptide that migrates aberrantly at 60 kD by SDS-PAGE. Rabbit antibodies raised against this protein's recently described amino-terminal epitope react with a previously identified 52-kD human Ro protein and immunoprecipitate the human cytoplasmic RNAs. Ultraviolet light cross-linking studies suggest that this Ro protein binds each of the four major human cytoplasmic RNAs. The deduced amino acid sequence is 63% homologous to an Onchocerca volvulus antigen. Southern filter hybridization analysis indicates that this gene is not highly polymorphic and exists as a single copy in the human genome. Chromosomal localization studies place this gene on the short arm of chromosome 19 near the gene encoding the low density lipoprotein receptor.