Subject(s)
Meat , Neoplasms , Humans , Meat/adverse effects , Risk Factors , Neoplasms/chemically induced , DietABSTRACT
Herd immunity by mass vaccination offers the potential to substantially limit the continuing spread of COVID-19, but high levels of vaccine hesitancy threaten this goal. In a cross-country analysis of vaccine hesitant respondents across Latin America in January 2021, we experimentally tested how five features of mass vaccination campaigns-the vaccine's producer, efficacy, endorser, distributor, and current population uptake rate-shifted willingness to take a COVID-19 vaccine. We find that citizens preferred Western-produced vaccines, but were highly influenced by factual information about vaccine efficacy. Vaccine hesitant individuals were more responsive to vaccine messengers with medical expertise than political, religious, or media elite endorsements. Citizen trust in foreign governments, domestic leaders, and state institutions moderated the effects of the campaign features on vaccine acceptance. These findings can help inform the design of unfolding mass inoculation campaigns.
ABSTRACT
As safe and effective vaccines become widely available, attaining herd immunity and limiting the spread of COVID-19 will depend on individuals choosing to vaccinate-and doing so quickly enough to outpace mutations. Using online surveys conducted across six Latin American countries in January 2021, we experimentally assess messages designed to counteract informational deficiencies and collective action problems that may drive hesitancy. We first find that basic vaccine information persuades around 8% of hesitant individuals to become willing to vaccinate, reduces intended wait to vaccinate by 0.4 months, and increases willingness to encourage others to vaccinate. Rather than facilitating free riding, learning, or social conformity, additional information about others' behavior increases vaccine acceptance when respondents expect herd immunity will be achieved. Finally, priming the social approval benefits of vaccinating also increases vaccine acceptance. These results suggest that providing information and shaping social expectations and incentives could both significantly increase vaccine uptake.
Subject(s)
COVID-19/psychology , Vaccination Refusal/psychology , Vaccination/psychology , COVID-19/prevention & control , COVID-19 Vaccines/therapeutic use , Health Knowledge, Attitudes, Practice , Humans , Latin America , Patient Acceptance of Health Care/psychology , Patient Acceptance of Health Care/statistics & numerical data , Persuasive Communication , SARS-CoV-2/pathogenicity , Surveys and Questionnaires , Vaccination/statistics & numerical data , Vaccination Refusal/trends , Vaccines/pharmacologyABSTRACT
BACKGROUND: The availability of a sensitive and robust activity assay is a prerequisite for efficient enzyme production, purification, and characterization. Here we report on a spectrophotometric assay for lytic polysaccharide monooxygenase (LPMO), which is an advancement of the previously published 2,6-dimethoxyphenol (2,6-DMP)-based LPMO assay. The new assay is based on hydrocoerulignone as substrate and hydrogen peroxide as cosubstrate and aims toward a higher sensitivity at acidic pH and a more reliable detection of LPMO in complex matrices like culture media. RESULTS: An LPMO activity assay following the colorimetric oxidation of hydrocoerulignone to coerulignone was developed. This peroxidase activity of LPMO in the presence of hydrogen peroxide can be detected in various buffers between pH 4-8. By reducing the substrate and cosubstrate concentration, the assay has been optimized for minimal autoxidation and enzyme deactivation while maintaining sensitivity. Finally, the optimized and validated LPMO assay was used to follow the recombinant expression of an LPMO in Pichia pastoris and to screen for interfering substances in fermentation media suppressing the assayed reaction. CONCLUSIONS: The biphenol hydrocoerulignone is a better substrate for LPMO than the monophenol 2,6-DMP, because of a ~ 30 times lower apparent K M value and a 160 mV lower oxidation potential. This greatly increases the measured LPMO activity when using hydrocoerulignone instead of 2,6-DMP under otherwise similar assay conditions. The improved activity allows the adaptation of the LPMO assay toward a higher sensitivity, different buffers and pH values, more stable assay conditions or to overcome low concentrations of inhibiting substances. The developed assay protocol and optimization guidelines increase the adaptability and applicability of the hydrocoerulignone assay for the production, purification, and characterization of LPMOs.
ABSTRACT
The antibiotic monensin is fed to dairy cows to increase milk production efficiency. A fraction of this monensin is excreted into the cow manure. Previous studies have found that cow manure containing monensin can negatively impact the performance of anaerobic digesters, especially upon first introduction. Few studies have examined whether the anaerobic digester microbiome can adapt to monensin during the operating time. Here, we conducted a long-term time series study of four lab-scale anaerobic digesters fed with cow manure. We examined changes in both the microbiome composition and function of the anaerobic digesters when subjected to the dairy antibiotic monensin. In our digesters, monensin was not rapidly degraded under anaerobic conditions. The two anaerobic digesters that were subjected to manure from monensin feed-dosed cows exhibited relatively small changes in microbiome composition and function due to relatively low monensin concentrations. At higher concentrations of monensin, which we dosed directly to control manure (from dairy cows without monensin), we observed major changes in the microbiome composition and function of two anaerobic digesters. A rapid introduction of monensin to one of these anaerobic digesters led to the impairment of methane production. Conversely, more gradual additions of the same concentrations of monensin to the other anaerobic digester led to the adaptation of the anaerobic digester microbiomes to the relatively high monensin concentrations. A member of the candidate OP11 (Microgenomates) phylum arose in this anaerobic digester and appeared to be redundant with certain Bacteroidetes phylum members, which previously were dominating.IMPORTANCE Monensin is a common antibiotic given to dairy cows in the United States and is partly excreted with dairy manure. An improved understanding of how monensin affects the anaerobic digester microbiome composition and function is important to prevent process failure for farm-based anaerobic digesters. This time series study demonstrates how anaerobic digester microbiomes are inert to low monensin concentrations and can adapt to relatively high monensin concentrations by redundancy in an already existing population. Therefore, our work provides further insight into the importance of microbiome redundancy in maintaining the stability of anaerobic digesters.
Subject(s)
Anti-Bacterial Agents/pharmacology , Manure/microbiology , Microbiota/drug effects , Monensin/pharmacology , Anaerobiosis , Animals , Bacteria/metabolism , Bioreactors , Cattle/microbiology , Cattle/physiology , Dairying , Digestion , Female , Methane/metabolismABSTRACT
In adults treated with opioids for chronic pain, point-of-care urine drug screens (immunoassays) for detecting opioids show a false-negative rate of 1.9%, a sensitivity of 92%, and a specificity of 93% compared with the gold-standard liquid chromatography tandem mass spectrometry. Oxycodone has the highest rate of false-negative results at 25%; methadone has the lowest rate at 4% to 6% (strength of recommendation: A, 2 blinded diagnostic accuracy studies with similar results).
Subject(s)
Analgesics, Opioid/administration & dosage , Analgesics, Opioid/urine , Chronic Pain/drug therapy , Point-of-Care Systems , Substance Abuse Detection/methods , Urinalysis/methods , Humans , Sensitivity and SpecificityABSTRACT
STT3A encodes the catalytic subunit of the oligosaccharyltransferase complex. A congenital disorder of glycosylation caused by mutations in STT3A has only been reported in one family to date, associated with a Type I congenital disorder of glycosylation pattern of transferrin glycoforms. The authors describe a further 5 related individuals with a likely pathogenic variant in STT3A, 2 of whom also had variants in TUSC3. Common phenotypic features in all symptomatic individuals include developmental delay, intellectual disability, with absent speech and seizures. Two individuals also developed episodic hypothermia and altered consciousness. The family were investigated by autozygosity mapping, which revealed both a homozygous region containing STT3A and, in addition, a homozygous deletion of TUSC3 in one child. A likely pathogenic variant in STT3A was confirmed on Sanger sequencing of all affected individuals: the authors discuss the molecular findings in detail and further delineate the clinical phenotype of this rare disorder.
Subject(s)
Congenital Disorders of Glycosylation/genetics , Hexosyltransferases/genetics , Membrane Proteins/genetics , Polymorphism, Single Nucleotide/genetics , Adolescent , Adult , Child , Congenital Disorders of Glycosylation/diagnostic imaging , Electroencephalography , Family Health , Female , Homozygote , Humans , Magnetic Resonance Imaging , Male , Young AdultABSTRACT
PTRH2 is an evolutionarily highly conserved mitochondrial protein that belongs to a family of peptidyl-tRNA hydrolases. Recently, patients from two consanguineous families with mutations in the PTRH2 gene were reported. Global developmental delay associated with microcephaly, growth retardation, progressive ataxia, distal muscle weakness with ankle contractures, demyelinating sensorimotor neuropathy, and sensorineural hearing loss were present in all patients, while facial dysmorphism with widely spaced eyes, exotropia, thin upper lip, proximally placed thumbs, and deformities of the fingers and toes were present in some individuals. Here, we report a new family with three siblings affected by sensorineural hearing loss and peripheral neuropathy. Autozygosity mapping followed by exome sequencing identified a previously reported homozygous missense mutation in PTRH2 (c.254A>C; p.(Gln85Pro)). Sanger sequencing confirmed that the variant segregated with the phenotype. In contrast to the previously reported patient, the affected siblings had normal intelligence, milder microcephaly, delayed puberty, myopia, and moderate insensitivity to pain. Our findings expand the clinical phenotype and further demonstrate the clinical heterogeneity related to PTRH2 variants.
Subject(s)
Carboxylic Ester Hydrolases/genetics , Hearing Loss, Sensorineural/genetics , Homozygote , Mitochondrial Proteins/genetics , Mutation, Missense , Peripheral Nervous System Diseases/genetics , Adolescent , Base Sequence , Consanguinity , Disease Progression , Female , Gene Expression , Genetic Heterogeneity , Hearing Loss, Sensorineural/diagnosis , Hearing Loss, Sensorineural/physiopathology , Humans , Male , Myopia/physiopathology , Pain Insensitivity, Congenital/physiopathology , Pedigree , Peripheral Nervous System Diseases/diagnosis , Peripheral Nervous System Diseases/physiopathology , Phenotype , Puberty, Delayed/physiopathology , SiblingsABSTRACT
Supplemental vitamin D without calcium--in doses averaging as much as 800 IU per day--doesn't reduce the risk of hip, vertebral, or nonvertebral fractures in postmenopausal women and older men.
Subject(s)
Bone Density/drug effects , Calcium/therapeutic use , Dietary Supplements , Hip Fractures/prevention & control , Osteoporosis, Postmenopausal/prevention & control , Vitamin D/therapeutic use , Aged , Aged, 80 and over , Female , Humans , Male , Middle AgedSubject(s)
Arthralgia , Arthroscopy/methods , Menisci, Tibial , Physical Therapy Modalities , Arthralgia/etiology , Arthralgia/therapy , Evidence-Based Practice , Humans , Menisci, Tibial/surgery , Pain Management , Recovery of Function , Tibial Meniscus Injuries , Trauma Severity Indices , Treatment OutcomeABSTRACT
Urofacial syndrome (UFS) is an autosomal recessive congenital disease featuring grimacing and incomplete bladder emptying. Mutations of HPSE2, encoding heparanase 2, a heparanase 1 inhibitor, occur in UFS, but knowledge about the HPSE2 mutation spectrum is limited. Here, seven UFS kindreds with HPSE2 mutations are presented, including one with deleted asparagine 254, suggesting a role for this amino acid, which is conserved in vertebrate orthologs. HPSE2 mutations were absent in 23 non-neurogenic neurogenic bladder probands and, of 439 families with nonsyndromic vesicoureteric reflux, only one carried a putative pathogenic HPSE2 variant. Homozygous Hpse2 mutant mouse bladders contained urine more often than did wild-type organs, phenocopying human UFS. Pelvic ganglia neural cell bodies contained heparanase 1, heparanase 2, and leucine-rich repeats and immunoglobulin-like domains-2 (LRIG2), which is mutated in certain UFS families. In conclusion, heparanase 2 is an autonomic neural protein implicated in bladder emptying, but HPSE2 variants are uncommon in urinary diseases resembling UFS.
Subject(s)
Glucuronidase/genetics , Urinary Tract/physiopathology , Urologic Diseases/genetics , Animals , Facies , Female , Humans , Male , Mice , Mice, Inbred C57BL , Mutation , Urologic Diseases/physiopathologyABSTRACT
OBJECTIVES: Leri's pleonosteosis (LP) is an autosomal dominant rheumatic condition characterised by flexion contractures of the interphalangeal joints, limited motion of multiple joints, and short broad metacarpals, metatarsals and phalanges. Scleroderma-like skin thickening can be seen in some individuals with LP. We undertook a study to characterise the phenotype of LP and identify its genetic basis. METHODS AND RESULTS: Whole-genome single-nucleotide polymorphism genotyping in two families with LP defined microduplications of chromosome 8q22.1 as the cause of this condition. Expression analysis of dermal fibroblasts from affected individuals showed overexpression of two genes, GDF6 and SDC2, within the duplicated region, leading to dysregulation of genes that encode proteins of the extracellular matrix and downstream players in the transforming growth factor (TGF)-ß pathway. Western blot analysis revealed markedly decreased inhibitory SMAD6 levels in patients with LP. Furthermore, in a cohort of 330 systemic sclerosis cases, we show that the minor allele of a missense SDC2 variant, p.Ser71Thr, could confer protection against disease (p<1×10(-5)). CONCLUSIONS: Our work identifies the genetic cause of LP in these two families, demonstrates the phenotypic range of the condition, implicates dysregulation of extracellular matrix homoeostasis genes in its pathogenesis, and highlights the link between TGF-ß/SMAD signalling, growth/differentiation factor 6 and syndecan-2. We propose that LP is an additional member of the growing 'TGF-ß-pathies' group of musculoskeletal disorders, which includes Myhre syndrome, acromicric dysplasia, geleophysic dysplasias, Weill-Marchesani syndromes and stiff skin syndrome. Identification of a systemic sclerosis-protective SDC2 variant lays the foundation for exploration of the role of syndecan-2 in systemic sclerosis in the future.
Subject(s)
Chromosomes, Human, Pair 8/genetics , Gene Duplication , Growth Differentiation Factor 6/genetics , Hand Deformities, Congenital/genetics , Joint Diseases/congenital , Ossification, Heterotopic/genetics , Scleroderma, Systemic/genetics , Syndecan-2/genetics , Adult , Aged , Child, Preschool , Extracellular Matrix/metabolism , Facies , Female , Fibroblasts/metabolism , Gene Expression Profiling , Growth Differentiation Factor 6/metabolism , Hand Deformities, Congenital/metabolism , Hand Deformities, Congenital/physiopathology , Humans , Infant , Joint Diseases/genetics , Joint Diseases/metabolism , Joint Diseases/physiopathology , Male , Middle Aged , Ossification, Heterotopic/metabolism , Ossification, Heterotopic/physiopathology , Phenotype , Signal Transduction , Syndecan-2/metabolism , Transforming Growth Factor beta/metabolism , Young AdultABSTRACT
OBJECTIVES: We aimed to determine the proportion of individuals in our schwannomatosis cohort whose disease is associated with an LZTR1 mutation. METHODS: We used exome sequencing, Sanger sequencing, and copy number analysis to screen 65 unrelated individuals with schwannomatosis who were negative for a germline NF2 or SMARCB1 mutation. We also screened samples from 39 patients with a unilateral vestibular schwannoma (UVS), plus at least one other schwannoma, but who did not have an identifiable germline or mosaic NF2 mutation. RESULTS: We identified germline LZTR1 mutations in 6 of 16 patients (37.5%) with schwannomatosis who had at least one affected relative, 11 of 49 (22%) sporadic patients, and 2 of 39 patients with UVS in our cohort. Three germline mutation-positive patients in total had developed a UVS. Mosaicism was excluded in 3 patients without germline mutation in NF2, SMARCB1, or LZTR1 by mutation screening in 2 tumors from each. CONCLUSIONS: Our data confirm the relationship between mutations in LZTR1 and schwannomatosis. They indicate that germline mutations in LZTR1 confer an increased risk of vestibular schwannoma, providing further overlap with NF2, and that further causative genes for schwannomatosis remain to be identified.
Subject(s)
Neurilemmoma/genetics , Neurofibromatoses/genetics , Neuroma, Acoustic/genetics , Skin Neoplasms/genetics , Transcription Factors/genetics , Female , Genetic Predisposition to Disease , Germ-Line Mutation , Humans , Loss of Heterozygosity , Male , Pedigree , Sequence Analysis, DNAABSTRACT
Mutations in components of the major spliceosome have been described in disorders with craniofacial anomalies, e.g., Nager syndrome and mandibulofacial dysostosis type Guion-Almeida. The U5 spliceosomal complex of eight highly conserved proteins is critical for pre-mRNA splicing. We identified biallelic mutations in TXNL4A, a member of this complex, in individuals with Burn-McKeown syndrome (BMKS). This rare condition is characterized by bilateral choanal atresia, hearing loss, cleft lip and/or palate, and other craniofacial dysmorphisms. Mutations were found in 9 of 11 affected families. In 8 families, affected individuals carried a rare loss-of-function mutation (nonsense, frameshift, or microdeletion) on one allele and a low-frequency 34 bp deletion (allele frequency 0.76%) in the core promoter region on the other allele. In a single highly consanguineous family, formerly diagnosed as oculo-oto-facial dysplasia, the four affected individuals were homozygous for a 34 bp promoter deletion, which differed from the promoter deletion in the other families. Reporter gene and in vivo assays showed that the promoter deletions led to reduced expression of TXNL4A. Depletion of TXNL4A (Dib1) in yeast demonstrated reduced assembly of the tri-snRNP complex. Our results indicate that BMKS is an autosomal-recessive condition, which is frequently caused by compound heterozygosity of low-frequency promoter deletions in combination with very rare loss-of-function mutations.
Subject(s)
Choanal Atresia/genetics , Deafness/congenital , Gene Deletion , Heart Defects, Congenital/genetics , Promoter Regions, Genetic/genetics , Ribonucleoprotein, U5 Small Nuclear/genetics , Spliceosomes/genetics , Alleles , Child, Preschool , Choanal Atresia/diagnosis , Deafness/diagnosis , Deafness/genetics , Exosomes/genetics , Facies , Female , Gene Expression Profiling , Gene Frequency , Genes, Reporter , Heart Defects, Congenital/diagnosis , Heterozygote , Homozygote , Humans , Male , Mutation , Oligonucleotide Array Sequence Analysis , Pedigree , Phenotype , Ribonucleoprotein, U5 Small Nuclear/metabolism , Sequence Analysis, DNA , Spliceosomes/metabolismABSTRACT
PURPOSE: Heterozygous germline PTCH1 mutations are causative of Gorlin syndrome (naevoid basal cell carcinoma), but detection rates > 70% have rarely been reported. We aimed to define the causative mutations in individuals with Gorlin syndrome without PTCH1 mutations. METHODS: We undertook exome sequencing on lymphocyte DNA from four unrelated individuals from families with Gorlin syndrome with no PTCH1 mutations found by Sanger sequencing, multiplex ligation-dependent probe amplification (MLPA), or RNA analysis. RESULTS: A germline heterozygous nonsense mutation in SUFU was identified in one of four exomes. Sanger sequencing of SUFU in 23 additional PTCH1-negative Gorlin syndrome families identified a SUFU mutation in a second family. Copy-number analysis of SUFU by MLPA revealed a large heterozygous deletion in a third family. All three SUFU-positive families fulfilled diagnostic criteria for Gorlin syndrome, although none had odontogenic jaw keratocysts. Each SUFU-positive family included a single case of medulloblastoma, whereas only two (1.7%) of 115 individuals with Gorlin syndrome and a PTCH1 mutation developed medulloblastoma. CONCLUSION: We demonstrate convincing evidence that SUFU mutations can cause classical Gorlin syndrome. Our study redefines the risk of medulloblastoma in Gorlin syndrome, dependent on the underlying causative gene. Previous reports have found a 5% risk of medulloblastoma in Gorlin syndrome. We found a < 2% risk in PTCH1 mutation-positive individuals, with a risk up to 20× higher in SUFU mutation-positive individuals. Our data suggest childhood brain magnetic resonance imaging surveillance is justified in SUFU-related, but not PTCH1-related, Gorlin syndrome.
Subject(s)
Basal Cell Nevus Syndrome/genetics , Cerebellar Neoplasms/genetics , Germ-Line Mutation , Medulloblastoma/genetics , Receptors, Cell Surface/genetics , Repressor Proteins/genetics , Cerebellar Neoplasms/etiology , Humans , Magnetic Resonance Imaging , Medulloblastoma/etiology , Patched Receptors , Patched-1 Receptor , RiskABSTRACT
Distal arthrogryposis (DA) is a group of rare, clinically and genetically heterogeneous disorders primarily characterized by congenital contractures of the distal limb joints without a neuromuscular disease. Mutations in at least 8 different genes have been shown to cause DA. Here, we report a 4-generation Indian family with 18 affected members presenting variable features of camptodactyly, brachydactyly, syndactyly, decreased flexion palmar creases, ulnar deviation of the hands, sandal gaps and club feet. We undertook exome sequencing of 3 distantly related affected individuals. Bioinformatics filtering revealed a known pathogenic missense mutation c.188G>A (p.Arg63His) in TNNT3 in all 3 affected individuals that segregated with the phenotype. The affected individuals exhibit significant phenotypic variability. This study demonstrates the value of exome sequencing helping to define the causative variant in genetically heterogeneous disorders.
ABSTRACT
Chronic cough is increasingly being recognized as a process that has multiple initiating and perpetuating triggers. Obstructive sleep apnea has recently emerged as a possible disease that can lead to chronic cough. This review details the available clinical evidence that links these two disparate diseases and explores mechanistic bases of their relationship.
Subject(s)
Cough/epidemiology , Sleep Apnea, Obstructive/epidemiology , Chronic Disease , Continuous Positive Airway Pressure , Cough/diagnosis , Cough/physiopathology , Cough/prevention & control , Humans , Prevalence , Reflex , Risk Factors , Sleep Apnea, Obstructive/diagnosis , Sleep Apnea, Obstructive/physiopathology , Sleep Apnea, Obstructive/therapy , Treatment OutcomeABSTRACT
BACKGROUND: Chronic cough patients are rendered therapies for gastro-esophageal reflux (GERD), upper airway cough syndrome (UACS) and cough-variant asthma (CVA) with varying benefit. Idiopathic or unexplained cough has emerged as an important clinical entity in both primary care and subspecialty clinics. Recent evidence points to a link between chronic cough and untreated obstructive sleep apnea (OSA). METHODS: A prospective observational study was done to evaluate the effect of OSA therapy in patients with chronic cough. Patients enrolled into the study underwent questionnaires to evaluate for GERD, UACS and CVA along with screening questionnaires for OSA and daytime sleepiness. The Leicester cough questionnaire (LCQ) was done at baseline and during serial visits to evaluate cough intensity and was used as the primary outcome measure of the effect of CPAP therapy on chronic cough. RESULTS: Out of 37 patients enrolled into the study, only 28 patients had follow up LCQ scores available and therefore underwent analysis. 22/28 patients were suspected to have OSA based on abnormal STOP-BANG screening questionnaire scores and overnight oximetry abnormalities. Of these 19/28 patients had overnight attended polysomnography with definitive diagnosis of OSA yielding a 68% prevalence of OSA in our chronic cough population. Chronic cough patients treated for OSA tended to be older with a significantly higher BMI than chronic cough patients without OSA. Significant improvement of LCQ scores occurred with CPAP therapy for OSA in chronic cough patients. CONCLUSION: OSA is significantly prevalent in chronic cough patients. Subjects with chronic cough and OSA tend to be older and obese. Treatment of OSA in chronic cough patients yields significant improvement in their health status.
ABSTRACT
OBJECTIVE: Systemic lupus erythematosus (SLE) is a prototype autoimmune disease that is assumed to occur via a complex interplay of environmental and genetic factors. Rare causes of monogenic SLE have been described, providing unique insights into fundamental mechanisms of immune tolerance. The aim of this study was to identify the cause of an autosomal-recessive form of SLE. METHODS: We studied 3 siblings with juvenile-onset SLE from 1 consanguineous kindred and used next-generation sequencing to identify mutations in the disease-associated gene. We performed extensive biochemical, immunologic, and functional assays to assess the impact of the identified mutations on B cell biology. RESULTS: We identified a homozygous missense mutation in PRKCD, encoding protein kinase δ (PKCδ), in all 3 affected siblings. Mutation of PRKCD resulted in reduced expression and activity of the encoded protein PKCδ (involved in the deletion of autoreactive B cells), leading to resistance to B cell receptor- and calcium-dependent apoptosis and increased B cell proliferation. Thus, as for mice deficient in PKCδ, which exhibit an SLE phenotype and B cell expansion, we observed an increased number of immature B cells in the affected family members and a developmental shift toward naive B cells with an immature phenotype. CONCLUSION: Our findings indicate that PKCδ is crucial in regulating B cell tolerance and preventing self-reactivity in humans, and that PKCδ deficiency represents a novel genetic defect of apoptosis leading to SLE.