Concentrations of dehydroepiandrosterone-sulphate (DHEA-S) in people with cystic fibrosis on and off elexacaftor-tezacaftor-ivacaftor

BACKGROUND

Levels of sulfated Dehydroepiandrosterone (DHEA-S) are unknown in people with Cystic Fibrosis (pwCF). DHEA-S is reported to have an inverse association with inflammation and warrants evaluation in pwCF.

METHODS

We compared differences in DHEA-S and other hormones between pwCF (n = 180) and without CF (n = 180) and DHEA-S association with percent predicted forced expiratory volume in one second (ppFEV1). We also evaluated DHEA-S levels in people with CF on elexacaftor-tezacaftor-ivacaftor (ETI) (n = 145).

RESULTS

PwCF (not on ETI) had lower DHEA-S levels compared to healthy non-CF controls. DHEA-S levels in individuals with CF on ETI were similar to those without CF. Lower DHEA-S levels were associated with lower ppFEV1.

CONCLUSIONS

PwCF (not on ETI) have lower levels of DHEA-S than people without CF or people with CF on ETI. Additional studies are needed to investigate the impact of DHEA-S on the health of pwCF and mechanisms involved.

Performance of risk prediction models for post-liver transplant patient and graft survival over time

Given liver transplantation organ scarcity, selection of recipients and donors to maximize post-transplant benefit is paramount. Several scores predict post-transplant outcomes by isolating elements of donor and recipient risk, including the donor risk index, Balance of Risk, pre-allocation score to predict survival outcomes following liver transplantation/survival outcomes following liver transplantation (SOFT), improved donor-to-recipient allocation score for deceased donors only/improved donor-to-recipient allocation score for both deceased and living donors (ID2EAL-D/-DR), and survival benefit (SB) models. No studies have examined the performance of these models over time, which is critical in an ever-evolving transplant landscape. This was a retrospective cohort study of liver transplantation events in the UNOS database from 2002 to 2021. We used Cox regression to evaluate model discrimination (Harrell's C) and calibration (testing of calibration curves) for post-transplant patient and graft survival at specified post-transplant timepoints. Sub-analyses were performed in the modern transplant era (post-2014) and for key donor-recipient characteristics. A total of 112,357 transplants were included. The SB and SOFT scores had the highest discrimination for short-term patient and graft survival, including in the modern transplant era, where only the SB model had good discrimination (C ≥ 0.60) for all patient and graft outcome timepoints. However, these models had evidence of poor calibration at 3- and 5-year patient survival timepoints. The ID2EAL-DR score had lower discrimination but adequate calibration at all patient survival timepoints. In stratified analyses, SB and SOFT scores performed better in younger (< 40 y) and higher Model for End-Stage Liver Disease (≥ 25) patients. All prediction scores had declining discrimination over time, and scores relying on donor factors alone had poor performance. Although the SB and SOFT scores had the best overall performance, all models demonstrated declining performance over time. This underscores the importance of periodically updating and/or developing new prediction models to reflect the evolving transplant field. Scores relying on donor factors alone do not meaningfully inform post-transplant risk.

Gender-affirming hormone therapy in cystic fibrosis - A case of new Pseudomonas infection

Background

Little is known about the impact of hormone therapy on transgender youth with Cystic Fibrosis (CF). This case report describes an 18-year-old affirmed female with CF who was treated with hormone therapy associated in timing with new growth of Pseudomonas aeruginosa in her sputum culture.

Discussion

We highlight important considerations, including the impact of gender-affirming hormone therapy on overall CF disease course. Evidence supports that females with CF have worse outcomes than males, which are partly attributed to estrogen effects. Pseudomonas aeruginosa is one of the most prevalent pathogens in people with CF. Here, we highlight a transfemale who grows Pseudomonas aeruginosa for the first time since her youth, nearly 1 year after starting estrogen therapy. This is consistent with previous literature of an association between high estrogen levels and Pseudomonas aeruginosa prevalence, but has never been evaluated in a transgender population.

Conclusion

Through this case, we demonstrate the need for additional research to understand the relationship between gender-affirmative hormone transition and CF care and management.

Therapist Financial Strain and Turnover: Interactions with System-Level Implementation of Evidence-Based Practices

Therapist turnover is a major problem in community mental health. Financial strain, which is composed of cognitive, emotional, and behavioral responses to the experience of economic hardship, is an understudied antecedent of therapist turnover given the tumultuous financial environment in community mental health. We prospectively examined the relationship between therapist financial strain and turnover in 247 therapists in 28 community mental health agencies. We expected greater therapist financial strain to predict higher turnover and participation in a system-funded evidence-based practice (EBP) training initiative to alleviate this effect. Controlling for covariates, financial strain predicted therapist turnover (OR 1.12, p = .045), but not for therapists who participated in an EBP training initiative. Reducing financial strain and/or promoting EBP implementation may be levers to reduce turnover.

Effects of intrapulmonary percussive ventilation on airway mucus clearance: A bench model

AIM

To determine the ability of intrapulmonary percussive ventilation (IPV) to promote airway clearance in spontaneously breathing patients and those on mechanical ventilation.

METHODS

An artificial lung was used to simulate a spontaneously breathing patient (Group 1), and was then connected to a mechanical ventilator to simulate a patient on mechanical ventilation (Group 2). An 8.5 mm endotracheal tube (ETT) connected to the test lung, simulated the patient airway. Artificial mucus was instilled into the mid-portion of the ETT. A filter was attached at both ends of the ETT to collect the mucus displaced proximally (mouth-piece filter) and distally (lung filter). The IPV machine was attached to the proximal end of the ETT and was applied for 10-min each to Group 1 and 2. After each experiment, the weight of the various circuit components were determined and compared to their dry weights to calculate the weight of the displaced mucus.

RESULTS

In Group 1 (spontaneously breathing model), 26.8% ± 3.1% of the simulated mucus was displaced proximally, compared to 0% in Group 2 (the mechanically ventilated model) with a P-value of < 0.01. In fact, 17% ± 1.5% of the mucus in Group 2 remained in the mid-portion of the ETT where it was initially instilled and 80% ± 4.2% was displaced distally back towards the lung (P < 0.01). There was an overall statistically significant amount of mucus movement proximally towards the mouth-piece in the spontaneously breathing (SB) patient. There was also an overall statistically significant amount of mucus movement distally back towards the lung in the mechanically ventilated (MV) model. In the mechanically ventilated model, no mucus was observed to move towards the proximal/mouth piece section of the ETT.

CONCLUSION

This bench model suggests that IPV is associated with displacement of mucus towards the proximal mouthpiece in the SB patient, and distally in the MV model.

Non-participants in policy efforts to promote evidence-based practices in a large behavioral health system

Background

System-wide training initiatives to support and implement evidence-based practices (EBPs) in behavioral health systems have become increasingly widespread. Understanding more about organizations who do not participate in EBP training initiatives is a critical piece of the dissemination and implementation puzzle if we endeavor to increase access in community settings.

Methods

We conducted 30 1-h semi-structured interviews with leaders in non-participating agencies who did not formally participate in system-wide training initiatives to implement EBPs in the City of Philadelphia, with the goal to understand why they did not participate.

Results

We found that despite not participating in training initiatives, most agencies were adopting (and self-financing) some EBP implementation. Leadership from agencies that were implementing EBPs reported relying on previously trained staff to implement EBPs and acknowledged a lack of emphasis on fidelity. Most leaders at agencies not adopting EBPs did not have a clear understanding of what EBP is. Those familiar with EBPs in agencies not adopting EBPs reported philosophical objections to EBPs. When asked about quality assurance and treatment selection, leaders reported being guided by system audits.

Conclusions

While it is highly encouraging that many agencies are adopting EBPs on their own, significant questions about fidelity and implementation success more broadly remain.

Can mild head injury cause ischaemic stroke?

Five cases of ischaemic stroke preceded by minor head trauma in children are described. All patients had striatocapsular infarction. Three had no cerebrovascular abnormality; two had turbulent flow in the proximal middle cerebral artery. None of the patients had evidence of arterial dissection or any other risk factors for stroke. All made an excellent neurological recovery. Possible mechanisms include mechanical disruption to the flow in the perforating branches of the middle cerebral artery, intimal trauma and subsequent thrombosis, or arterial spasm induced by trauma. The specific susceptibility in affected children remains unexplained; both genetic and environmental factors (for example, previous chickenpox) may be implicated.

Two functional copies of the DGCR6 gene are present on human chromosome 22q11 due to a duplication of an ancestral locus

The DGCR6 (DiGeorge critical region) gene encodes a putative protein with sequence similarity to gonadal (gdl), a Drosophila melanogaster gene of unknown function. We mapped the DGCR6 gene to chromosome 22q11 within a low copy repeat, termed sc11.1a, and identified a second copy of the gene, DGCR6L, within the duplicate locus, termed sc11.1b. Both sc11.1 repeats are deleted in most persons with velo-cardio-facial syndrome/DiGeorge syndrome (VCFS/DGS), and they map immediately adjacent and internal to the low copy repeats, termed LCR22, that mediate the deletions associated with VCFS/DGS. We sequenced genomic clones from both loci and determined that the putative initiator methionine is located further upstream than originally described, but in a position similar to the mouse and chicken orthologs. DGCR6L encodes a highly homologous, functional copy of DGCR6, with some base changes rendering amino acid differences. Expression studies of the two genes indicate that both genes are widely expressed in fetal and adult tissues. Evolutionary studies using FISH mapping in several different species of ape combined with sequence analysis of DGCR6 in a number of different primate species indicate that the duplication is at least 12 million years old and may date back to before the divergence of Catarrhines from Platyrrhines, 35 mya. These data suggest that there has been selective evolutionary pressure toward the functional maintenance of both paralogs. Interestingly, a full-length HERV-K provirus integrated into the sc11.1a locus after the divergence of chimpanzees and humans.

Treatment of leukemia relapse after bone marrow transplantation with interferon-alpha and interleukin 2

A 16-year-old girl with refractory AML received unmanipulated BMT from an unrelated donor. Leukemia relapse occurred 82 days later. The patient was then treated with IL-2 1.8 x 10(6) U/m2 for 5 days per week and 2.5 MU/m2 IFN-alpha three times per week. Toxicities included fever, skin rash, somnolence and a generalized seizure. Treatment was stopped after 2 weeks. Acute GVHD developed at the end of therapy and the patient's leukemia went into remission. She died of fungal pneumonia 30 days later. We conclude that a combination of cytokines may be useful in treating relapsed leukemia after BMT.

Permeation and metabolism of anti-HIV and endogenous nucleosides in human immune effector cells

Numerous anti-HIV drugs are synthetic analogs of endogenous nucleosides. Therefore it is of interest to see if a facilitated nucleoside transport system exists to mediate their uptake into human immune effector cells that are known HIV targets. Nucleoside permeation and metabolism in lymphocytes, macrophages and bone marrow cells isolated from healthy human volunteers were studied, using uridine as the prototype endogenous nucleoside. There are saturable broad specificity nucleoside transport systems in all three cell types, all of which were inhibited by dipyridamole. The Vmax and Km values for uridine transport were 0.05 +/- 0.01 pmol/sec/10(6) cells and 18.4 +/- 4.2 microM, respectively, for lymphocytes, 0.04 +/- 0.01 pmol/sec/10(6) cells and 25.3 +/- 6.6 microM, respectively, for macrophages, and 0.03 +/- 0.01 pmol/sec/10(6) cells and 90.2 +/- 10.1 microM, respectively, for bone marrow mononuclear cells. Anti-HIV dideoxynucleosides such as azidothymidine (AZT), 2',3'-dideoxycytidine (DDC), 2',3'-dideoxyinosine (DDI), 2',3'-dideoxyadenosine (DDA), and 2',3'-dideoxythymidine (DDT) are not substrates of this nucleotide transport system; hence, little or no drug accumulated inside the cells after 60 sec. Equilibration of cells with uridine or dideoxynucleosides for 2 hr resulted in high levels of cellular uridine and DDA, low levels of cellular AZT, but undetectable levels of the other analogs in all three cell types. Active metabolite levels in lymphocytes as assayed by HPLC correlated with the drug permeation results. Our data demonstrated that DDC, DDI, and DDT are not substrates for the nucleoside transporter and cannot diffuse readily across the cell membrane of human immune effector cells. Future anti-HIV drug development efforts should consider drugs that are substrates of the nucleotide transporter to ensure rapid and complete uptake into target cells.

Measurement of NK activity in effector cells purified from canine peripheral lymphocytes

Natural killer (NK) cells spontaneously lyse a variety of tumor cells in vitro, and are believed to play an important role in host resistance to tumor growth and metastasis in vivo. As part of our work in comparative oncology, we have designed and validated a canine NK cell assay. Of several lymphocyte isolation techniques evaluated, sedimentation of whole blood through a two-step Ficoll/Hypaque gradient (sp. gr. 1.066/1.119) followed by plastic adherence of monocytes resulted in the most pure lymphocyte population (> 95% lymphocytes). Of four cell lines evaluated as targets in the NK assay, a canine thyroid adenocarcinoma (CTAC) cell line was determined to be most sensitive, and a lymphoblastoid (CT45-S) cell line was determined to be most resistant to NK lysis. A 15 h effector-target incubation period using these targets resulted in reproducible measurement of cell specific lytic activity. Passage of canine lymphocytes through nylon wool columns did not result in a significant increase in NK activity. A final sedimentation of purified lymphocytes through a 45/50% Percoll gradient concentrated NK activity into a single band of lymphocytes. Lymphocytes forming conjugates with CTAC target cells were 5.5-6.5 microns in diameter, and were characterized by a reniform nucleus and varying numbers of electron-dense cytoplasmic granules.

Antiviral nucleoside toxicity in canine bone marrow progenitor cells and its relationship to drug permeation

The most promising nucleoside analogs that are currently undergoing preclinical and clinical testing for anti-HIV activity belong to the dideoxynucleoside group. We have studied the toxicity of 3'-azido,3'-deoxythymidine (AZT), 2',3'-dideoxycytidine (DDC), and 2',3'-dideoxyinosine (DDI) in canine bone marrow progenitor cells in culture. AZT potently inhibited both canine CFU-GM and CFU-E with IC50 values of 2 and 8 mumol/l respectively, while DDC was relatively non-toxic to either progenitor with IC50 of > 200 mumol/l and 80 mumol/l respectively. DDI was mildly toxic to the bone marrow progenitors, with IC50 values of 62 mumol/l for CFU-GM and 70 mumol/l for CFU-E. Dipyridamole, a nucleoside transport inhibitor, did not influence the toxicity of these dideoxynucleosides in either progenitor at concentrations up to 10 mumol/l. Using uridine as the prototype endogenous nucleoside, we have demonstrated that there is a saturable "zero-trans" nucleoside transport system in canine bone marrow mononuclear cells, which is completely inhibited by 1 mumol/l dipyridamole (Ki = 0.02 mumol/l). None of the dideoxynucleosides appeared to be a substrate for this transport system, and dipyridamole did not alter their influx. Permeation of radiolabeled AZT into bone marrow mononuclear cells was slow and non-saturable, while the permeation of DDI was even slower. DDC did not permeate bone marrow cells well, with very little cell accumulation even after 2 hours of equilibration. Our toxicity data from canine bone marrow progenitor cells paralleled the clinical hematotoxicity profiles of these dideoxynucleosides in AIDS patients and suggest that the myelotoxicity of a nucleoside analog is related to its ability to permeate the progenitor cells in question. Canine bone marrow progenitor cultures may serve well as an in vitro model for drug hematotoxicity studies.

Antibody response to epitopes of chlamydial major outer membrane proteins on infectious elementary bodies and of the reduced polyacrylamide gel electrophoresis-separated form

Approximately 60% of the outer membrane of chlamydial elementary bodies (EBs) consists of the major outer membrane protein (MOMP) that has structural and metabolic functions. The antigenic properties of MOMPs from mammalian strains of serovars 1 and 2 and an avian strain of Chlamydia psittaci were analyzed. Polyclonal-monospecific antisera (PMAs), one monoclonal antibody (MAb), and polyclonal antisera (PAs) were produced against reduced polyacrylamide gel electrophoresis-separated MOMPs and against infectious EBs. Three PMAs and the MAb, which were induced by reduced polyacrylamide gel electrophoresis-separated MOMPs, reacted strongly in Western blot (immunoblot) assays with MOMPs of serovar 1 and 2 strains as well as with that of the avian strain 6BC, and two of these PMAs reacted weakly (dilution, 1:20) with the MOMP of strain LGV-2. The third PMA and the MAb against the MOMP of the serovar 2 strain did not react with the MOMP of LGV-2. Four PAs were produced against infectious EBs of the serovar 1 strain. One of these PAs reacted with the homologous MOMP and that of the avian strain 6BC but did not recognize MOMPs of other chlamydial strains. Three of the PAs reacted with MOMPs of homologous strains only and failed to recognize MOMPs of avian, serovar 2, and LGV-2 strains. Five PAs induced against infectious EBs of the serovar strain 2 reacted only with the MOMPs of the homologous strains and failed to recognize MOMPs of other strains of chlamydiae. Consequently, MOMPs of C. psittaci strains possess genus-, species-, and serovar-specific epitopes whereby the immune response to serovar-specific epitopes of MOMP predominate when infectious EBs are used for immunization.

Effects of age, temperature-season, and breed on blood characteristics of dairy cattle

Two hundred twenty four dairy cattle (6 mo to second calving) representing four breeds (169 Holstein, 24 Guernsey, 19 Jersey, 12 Brown Swiss) were used to determine effects of age, temperature-season, and breed on blood characteristics. A total of 1183 blood samples were collected by jugular venipuncture in the middle of each temperature-season. Covariate age affected blood profile except for hemoglobin, oxyhemoglobin, glutamic-oxalacetic transaminase, and albumin. Temperature-season increased or decreased all measures except enzyme creatine phosphokinase, total creatine phosphokinase, calcium and phosphorus. Years differed for all measures except hemoglobin and oxyhemoglobin. Except for enzyme creatine phosphokinase, total creatine phosphokinase, and phosphorus, breeds differed in other measures. There were interactions between temperature-season and year, temperature-season and breed, and year and breed. Differences among temperature-seasons were not consistent from year to year. Breed differences were not consistent from temperature-season to temperature-season for calcium or protein-bound iodine. Breed differences were not consistent from year to year for glutamic-oxaloacetic transaminase, total protein, albumin, or calcium.

Retention of differentiated properties in an established dog kidney epithelial cell line (MDCK)

Madin-Darby canine kidney (MDCK) cells grown in tissue culture have the morphological properties of distal tubular epithelial cells, form tight junctions, and lack several proximal tubular enzyme markers. Adenylate cyclase in these cells was stimulated by vasopressin, oxytocin, prostaglandins E1 and E2, glucagon, and cholera toxin. Hormone-stimulated adenylate cyclase activity in isolated membrane preparations was dependent on low concentrations of GTP and had the MgCl2 and pH optima expected for the kidney enzyme. The results, as well as the demonstration of enhanced hemicyst formation induced by cyclic AMP, suggest that the MDCK cell line has retained the differentiated properties of the kidney epithelial cell of origin. When MDCK cells were injected into baby nude mice, continuous nodule growth was observed until adulthood was attained. Histological studies revealed the presence of two cell types: normal mouse fibroblasts which comprise 80--90% of the solid nodule mass, and MDCK cells, which formed epithelial sheets lining internal fluid-filled glands. Electron microscope analysis showed that the mucosal surfaces of the cells were characterized by microvilli which faced the lumen of the glands, that adjacent MDCK cells were joined by tight junctions, and that the serosal surfaces of the epithelial sheets were characterized by smooth plasma membranes which were lined by a continuous basement membrane. These observations lead to the conclusion that the MDCK cells retain regional differentiation of their plasma membranes and the ability to regenerate kidney tubule-like structures in vivo.