Patient-Induced Pluripotent Stem Cell-Derived Hepatostellate Organoids Establish a Basis for Liver Pathologies in Telomeropathies

BACKGROUND & AIMS

Dyskeratosis congenita (DC) is a telomere biology disorder caused primarily by mutations in the DKC1 gene. Patients with DC and related telomeropathies resulting from premature telomere dysfunction experience multiorgan failure. In the liver, DC patients present with nodular hyperplasia, steatosis, inflammation, and cirrhosis. However, the mechanism responsible for telomere dysfunction-induced liver disease remains unclear.

METHODS

We used isogenic human induced pluripotent stem cells (iPSCs) harboring a causal DC mutation in DKC1 or a CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/Cas9)-corrected control allele to model DC liver pathologies. We differentiated these iPSCs into hepatocytes (HEPs) or hepatic stellate cells (HSCs) followed by generation of genotype-admixed hepatostellate organoids. Single-cell transcriptomics were applied to hepatostellate organoids to understand cell type-specific genotype-phenotype relationships.

RESULTS

Directed differentiation of iPSCs into HEPs and stellate cells and subsequent hepatostellate organoid formation revealed a dominant phenotype in the parenchyma, with DC HEPs becoming hyperplastic and also eliciting a pathogenic hyperplastic, proinflammatory response in stellate cells independent of stellate cell genotype. Pathogenic phenotypes in DKC1-mutant HEPs and hepatostellate organoids could be rescued via suppression of serine/threonine kinase AKT (protein kinase B) activity, a central regulator of MYC-driven hyperplasia downstream of DKC1 mutation.

CONCLUSIONS

Isogenic iPSC-derived admixed hepatostellate organoids offer insight into the liver pathologies in telomeropathies and provide a framework for evaluating emerging therapies.

GSK3 inhibition rescues growth and telomere dysfunction in dyskeratosis congenita iPSC-derived type II alveolar epithelial cells

Dyskeratosis congenita (DC) is a rare genetic disorder characterized by deficiencies in telomere maintenance leading to very short telomeres and the premature onset of certain age-related diseases, including pulmonary fibrosis (PF). PF is thought to derive from epithelial failure, particularly that of type II alveolar epithelial (AT2) cells, which are highly dependent on Wnt signaling during development and adult regeneration. We use human induced pluripotent stem cell-derived AT2 (iAT2) cells to model how short telomeres affect AT2 cells. Cultured DC mutant iAT2 cells accumulate shortened, uncapped telomeres and manifest defects in the growth of alveolospheres, hallmarks of senescence, and apparent defects in Wnt signaling. The GSK3 inhibitor, CHIR99021, which mimics the output of canonical Wnt signaling, enhances telomerase activity and rescues the defects. These findings support further investigation of Wnt agonists as potential therapies for DC-related pathologies.

Temperature and Density on the Forsterite Liquid-Vapor Phase Boundary

The physical processes during planet formation span a large range of pressures and temperatures. Giant impacts, such as the one that formed the Moon, achieve peak pressures of 100s of GPa. The peak shock states generate sufficient entropy such that subsequent decompression to low pressures intersects the liquid-vapor phase boundary. The entire shock-and-release thermodynamic path must be calculated accurately in order to predict the post-impact structures of planetary bodies. Forsterite (Mg2SiO4) is a commonly used mineral to represent the mantles of differentiated bodies in hydrocode models of planetary collisions. Here, we performed shock experiments on the Sandia Z Machine to obtain the density and temperature of the liquid branch of the liquid-vapor phase boundary of forsterite. This work is combined with previous work constraining pressure, density, temperature, and entropy of the forsterite principal Hugoniot. We find that the vapor curves in previous forsterite equation of state models used in giant impacts vary substantially from our experimental results, and we compare our results to a recently updated equation of state. We have also found that due to under-predicted entropy production on the principal Hugoniot and elevated temperatures of the liquid vapor phase boundary of these past models, past impact studies may have underestimated vapor production. Furthermore, our results provide experimental support to the idea that giant impacts can transform much of the mantles of rocky planets into supercritical fluids.

A Body of Evidence: Barriers to Family Viewing After Death by Gun Violence

BACKGROUND

Gun violence remains a staggering public health care crisis. Although viewing the victim's body is essential to the grieving process, this practice is not universally practiced in the trauma bay and may not be supported by nurses. This study investigates how trauma nurses perceive bereavement and the potential barriers to family viewing after death by gun violence.

METHODS

A survey designed to assess demographics, current practices, knowledge of policies, and personal beliefs regarding family viewing after violent crime was sent electronically to members of the Society of Trauma Nurses. Participants were asked to rank the importance of 14 viewing barriers. Descriptive analysis and perception of barriers between those who did and did not permit viewing were compared using Mann-Whitney tests. *P < 0.05 is considered significant.

RESULTS

Of the 212 participants, the majority were white, female nurses (86%), aged 30 to 60 y who worked in an urban or suburban setting (58% and 30%). Only 15% had a written hospital policy with the majority not knowing if the police (68%) or medical examiner (74%) had written policies. Despite lack of guidelines, viewings did routinely occur (68%), but only 37% permitted touching. Nurses who did not permit viewing were more likely to rank legal concerns and trauma bay environment as significant barriers.

CONCLUSIONS

Although family viewing after gun violence frequently occurs in the trauma bay, there are significant barriers that are compounded by lack of formal policies. Collaboration with police and medical examiners could mitigate these fears while promoting a safe and more family-centered experience.

The spectrum of mutations in TBX3: Genotype/Phenotype relationship in ulnar-mammary syndrome

Ulnar-mammary syndrome (UMS) is a pleiotropic disorder affecting limb, apocrine-gland, tooth, hair, and genital development. Mutations that disrupt the DNA-binding domain of the T-box gene, TBX3, have been demonstrated to cause UMS. However, the 3' terminus of the open reading frame (ORF) of TBX3 was not identified, and mutations were detected in only two families with UMS. Furthermore, no substantial homology outside the T-box was found among TBX3 and its orthologues. The subsequent cloning of new TBX3 cDNAs allowed us to complete the characterization of TBX3 and to identify alternatively transcribed TBX3 transcripts, including one that interrupts the T-box. The complete ORF of TBX3 is predicted to encode a 723-residue protein, of which 255 amino acids are encoded by newly identified exons. Comparison of other T-box genes to TBX3 indicates regions of substantial homology outside the DNA-binding domain. Novel mutations have been found in all of eight newly reported families with UMS, including five mutations downstream of the region encoding the T-box. This suggests that a domain(s) outside the T-box is highly conserved and important for the function of TBX3. We found no obvious phenotypic differences between those who have missense mutations and those who have deletions or frameshifts.

The Genome Sequence DataBase: towards an integrated functional genomics resource

During 1998 the primary focus of the Genome Sequence DataBase (GSDB; http://www.ncgr.org/gsdb ) located at the National Center for Genome Resources (NCGR) has been to improve data quality, improve data collections, and provide new methods and tools to access and analyze data. Data quality has been improved by extensive curation of certain data fields necessary for maintaining data collections and for using certain tools. Data quality has also been increased by improvements to the suite of programs that import data from the International Nucleotide Sequence Database Collaboration (IC). The Sequence Tag Alignment and Consensus Knowledgebase (STACK), a database of human expressed gene sequences developed by the South African National Bioinformatics Institute (SANBI), became available within the last year, allowing public access to this valuable resource of expressed sequences. Data access was improved by the addition of the Sequence Viewer, a platform-independent graphical viewer for GSDB sequence data. This tool has also been integrated with other searching and data retrieval tools. A BLAST homology search service was also made available, allowing researchers to search all of the data, including the unique data, that are available from GSDB. These improvements are designed to make GSDB more accessible to users, extend the rich searching capability already present in GSDB, and to facilitate the transition to an integrated system containing many different types of biological data.

Putting a lid on injury costs: the economic impact of the California motorcycle helmet law

BACKGROUND

This study analyzed the effect of California's motorcycle helmet law on injury costs.

METHODS

An economic evaluation was performed using state hospital discharge data, county-level cost data, and statewide crash reports to estimate the costs, charges, and lost productivity from motorcycle injuries. Total and per person costs and changes in these costs were estimated.

RESULTS

Total medical care costs were $35 million less in 1993 than in 1991, a reduction of 35%. Costs decreased for all payer categories, and 73% of the reduced hospitalization costs were attributable to reduced costs for patients with head injuries. Initial hospital costs for patients with head injuries were $18,527 compared with $10,350 for patients without head injuries.

CONCLUSION

During the first 2 years of implementation of California's helmet law, there were reduced costs for injuries and fatalities and large dollar savings to the state and other payers compared with the previous year.

Combination therapy with thymosin alpha1 and interferon for the treatment of chronic hepatitis C infection: a randomized, placebo-controlled double-blind trial

Hepatitis C is a major cause of liver disease leading to cirrhosis. Although interferon (IFN) is the only approved therapy, treatment is characterized by low response rates and dose-limiting side effects. We evaluated the addition of thymosin alpha1 (TA1), an immunomodulatory peptide, to the standard treatment regimen for hepatitis C to determine if combination therapy shows biological activity using outcome measures including normalization of alanine aminotransferase levels, histological activity, and viral load during treatment. We performed a randomized, double-blind, placebo-controlled trial to compare the biological activity of a combination TA1 and IFN with that seen for IFN alone in patients with chronic hepatitis C infection. One hundred nine patients were randomized for intention to treat and received 1.6 mg of TA1 subcutaneously twice weekly and 3 MU of IFN three times weekly; 3 MU of IFN three times weekly and placebo TA1; or placebo for both agents. All patients had chronic HCV infection with confirmation of chronic hepatitis on liver biopsy. Biochemical responders were followed up until alanine aminotransferase (ALT) levels became abnormal or for 26 weeks, and relapsers were retreated for 26 weeks in the same treatment arm. One hundred three patients completed treatment for 26 weeks, and six patients dropped out. The groups were similar with regard to sex, gender distribution, baseline histological activity index (HAI) score, risk factors, and viral titers. End-of-treatment biochemical response was seen in 37.1% of patients treated with combination therapy, 16.2% of patients treated with IFN alone, and 2.7% of untreated controls by intent-to-treat analysis (IFN/TA1 vs. IFN, chi2 = 4.05, P = .04). HCV RNA clearance was seen in 37.1% of IFN/TA1-treated patients and 18.9% of IFN-treated subjects. Mean HCV RNA titers were significantly lower than baseline at weeks 8, 16, and 24 after drug initiation among patients treated with IFN/TA1 but not in the other treatment arms. Histological improvement, as evidenced by a decrease in HAI of more than two points, occurred in the combination therapy arm more frequently than in comparison groups. Cumulative sustained biochemical responses were 14.2% and 8.1% in the IFN/TA1 and IFN arms, respectively, based on an intention-to-treat model. The combination of TA1 and standard IFN treatment for chronic hepatitis C showed evidence of biological activity at the completion of treatment by biochemical, histological, and virological outcome measures. Further research involving longer duration and varied dosing is needed.

Familial ring (19) chromosome mosaicism: case report and review

Ring (19) chromosomal mosaicism has been identified in a 14-month-old girl referred for cytogenetic evaluation due to microcephaly and developmental delay with autistic-like mannerisms. An analysis of her peripheral blood lymphocytes showed a 46,XX,r(19) cell line in 119/121 of cells examined. Of the two remaining cells, one had a normal female chromosome complement and the other showed loss of one of the chromosome 19 homologs. Further analysis by fluorescence in situ hybridization using an all human telomere probe showed the presence of a single hybridization signal on the r(19) chromosome. Subsequent cytogenetic characterization of cells derived from the patient's phenotypically normal mother also demonstrated the presence of a ring 19 chromosome in 4/100 cells. The remaining cells had a normal female chromosome complement. These findings represent the first reported case of familial ring 19 mosaicism. The cytogenetic and clinical findings in these two individuals are discussed in relation to six previously reported cases of de novo ring chromosome 19 mosaicism.

Clinical analysis of a large kindred with the Pallister ulnar-mammary syndrome

The ulnar-mammary syndrome (UMS) is an autosomal dominant disorder characterized by posterior limb deficiencies or duplications, apocrine/mammary gland hypoplasia and/or dysfunction, abnormal dentition, delayed puberty in males, and genital anomalies. We present the clinical descriptions of 33 members of a six generation kindred with UMS. The number of affected individuals in this family is more than the sum of all previously reported cases of UMS. The clinical expression of UMS is highly variable. While most patients have limb deficiencies, the range of abnormalities extends from hypoplasia of the terminal phalanx of the 5th digit to complete absence of the ulna and 3rd, 4th, and 5th digits. Moreover, affected individuals may have posterior digital duplications with or without contralateral limb deficiencies. Apocrine gland abnormalities range from diminished axillary perspiration with normal breast development and lactation, to complete absence of the breasts and no axillary perspiration. Dental abnormalities include misplaced or absent teeth. Affected males consistently undergo delayed puberty, and both sexes have diminished to absent axillary hair. Imperforate hymen were seen in some affected women. A gene for UMS was mapped to chromosome area 12q23-q24.1. A mutation in the gene causing UMS can interfere with limb patterning in the proximal/distal, anterior/posterior, and dorsal/ventral axes. This mutation disturbs development of the posterior elements of forearm, wrist, and hand while growth and development of the anterior elements remain normal.

A gene for ulnar-mammary syndrome maps to 12q23-q24.1

Ulnar-mammary syndrome (UMS) is an autosomal dominant disorder characterized by posterior limb deficiencies or duplications, apocrine/mammary gland hypoplasia and/or dysfunction, abnormal dentition, delayed puberty and genital anomalies. We report the mapping of a gene causing UMS to chromosome 12q23-24.1. Linkage analysis generated a positive lod score of 6.21 at theta = 0.00 with the marker D12S79, and recombinants bracket the UMS gene to a 21 cM region. This region contains a locus for Holt-Oram syndrome (HOS) suggesting that the genes for UMS and HOS may be allelic or closely linked. The identification of the gene causing UMS will be an important step toward understanding the molecular mechanisms that control limb and apocrine gland development.

Survival in trisomy 18

Prenatal diagnosis of trisomy 18 by amniocentesis in the latter half of pregnancy is now a common event. Accurate prognostic information is crucial for families making decisions about delivery management. Three recently published studies showed much shorter survival for trisomy 18 than was reported by earlier papers. For this reason, we studied trisomy 18 survival. We examined chromosome laboratory records to find all trisomy 18 diagnoses made in Utah between 1979 and 1988. Death certificates and hospital records were used to determine survival. We found 64 liveborn cases with trisomy 18 out of 388,563 total births over the 10-year period, a prevalence of 1/6071. Our results show a median survival of 4 days and a 1 week survival of 45%, similar to that reported in the 3 recent studies. However, we had a significantly greater survival at 6 months (9% in Utah versus 3% in Denmark) and 1 year (5% versus 0 in the 3 studies). In contrast to recent studies, earlier investigations showed 80% survival at 2 weeks and 8% at 1 year. It is not surprising that recent studies show shorter survival, since in the 1960s the diagnosis was typically not made until age 2 months. With prenatal and neonatal diagnosis many cases which would have died prior to detection in earlier times are now diagnosed. The longer survival discrepancies are more difficult to explain, but may simply be due to small numbers.

The relationship between disease severity, disability and psychological distress in patients undergoing PUVA treatment for psoriasis

BACKGROUND

Patients suffering from severe psoriasis report high levels of personal distress and disability as a result of their disease.

OBJECTIVE

The purpose of this study was to examine the relationship between disease severity, personal distress and disability.

METHODS

Twenty-two patients provided a self-rating of disease severity and completed the Psoriasis Disability Index (PDI) and the General Health Questionnaire (GHQ). A dermatologist provided a clinical assessment from the case notes.

RESULTS

Although the clinical assessment was not related to patient ratings, patient-rated severity scores, GHQ and PDI were correlated with each other. GHQ could only be predicted by disease severity when it was mediated by PDI scores.

CONCLUSIONS

These results indicated that psoriasis affects psychological distress through its effects on the patients' everyday lives.

Timeliness of national reporting of communicable diseases: the experience of the National Electronic Telecommunications System for Surveillance

The timeliness of reporting four nationally notifiable diseases was examined using data reported via the National Electronic Telecommunications System for Surveillance. Timeliness of reporting varied by disease (bacterial meningitis: median 20 days; salmonellosis: median 22 days; shigellosis: median 23 days; and hepatitis A: median 33 days) and by state. These findings indicate a need to standardize surveillance definitions and to account for reporting differences between states in interpreting regional disease trends or detecting multistate disease outbreaks.