Spatiotemporal immune atlas of a clinical-grade gene-edited pig-to-human kidney xenotransplant.

Pig-to-human xenotransplantation is rapidly approaching the clinical arena; however, it is unclear which immunomodulatory regimens will effectively control human immune responses to pig xenografts. Here, we transplant a gene-edited pig kidney into a brain-dead human recipient on pharmacologic immunosuppression and study the human immune response to the xenograft using spatial transcriptomics and single-cell RNA sequencing. Human immune cells are uncommon in the porcine kidney cortex early after xenotransplantation and consist of primarily myeloid cells. Both the porcine resident macrophages and human infiltrating macrophages express genes consistent with an alternatively activated, anti-inflammatory phenotype. No significant infiltration of human B or T cells into the porcine kidney xenograft is detectable. Altogether, these findings provide proof of concept that conventional pharmacologic immunosuppression may be able to restrict infiltration of human immune cells into the xenograft early after compatible pig-to-human kidney xenotransplantation.

Aneurysmal bone cysts: A UK wide tumor center experience.

BACKGROUND AND OBJECTIVES: This multicenter retrospective series of consecutive extra-spinal aneurysmal bone cysts aims to identify risk factors for treatment failure. METHODS: Aneurysmal bone cysts treated within seven collaborating centers with over 12-months follow-up were eligible for inclusion. Survival analyses were performed to identify variables associated with recurrence using log-rank tests and Cox proportional hazard regression. RESULTS: One hundred and fifteen (M:F 60:55) patients were included. Median age at presentation was 13 years and median follow-up was 27 months. Seventy-five patients underwent surgical curettage and 27% of these required further intervention for recurrence. Of the 30 patients who underwent biopsy with limited percutaneous curettage as initial procedure, 47% required no further treatment. Patients under 13 years (log-rank p = 0.006, HR 2.3, p = 0.011) and those treated who had limited curettage (log-rank p = 0.001, HR 2.7, p = 0.002) had a higher risk of recurrence/persistence. CONCLUSIONS: There is a high risk of recurrence following surgical treatment for aneurysmal bone cysts and this risk is higher in young patients. However, the cyst heals in a substantial number of patients who have a limited curettage at the time of biopsy.

Electronic, magnetic, and structural properties of NiFeMnAl.

Half-metallic Heusler compounds have been extensively studied in the recent years, both experimentally and theoretically, for potential applications in spin-based electronics. Here, we present the results of a combined theoretical and experimental study of the quaternary Heusler compound NiFeMnAl. Our calculations indicate that this material is half-metallic in the ground state and maintains its half-metallic electronic structure under a considerable range of external hydrostatic pressure and biaxial strain. NiFeMnAl crystallizes in the regular cubic Heusler structure, and exhibits ferromagnetic alignment. The practical feasibility of the proposed system is confirmed in the experimental section of this work. More specifically, a bulk ingot of NiFeMnAl was synthesized in A2 type disordered cubic structure using arc melting. It shows a high Curie temperature of about 468 K and a saturation magnetization of 2.3µB/f.u. The measured magnetization value is smaller than the one calculated for the ordered structure. This discrepancy is likely due to the A2 type atomic disorder, as demonstrated by our calculations. We hope that the presented results may be useful for researchers working on practical applications of spin-based electronics.

Trends in pathology diagnoses during 10 years of a colorectal cancer screening programme.

AIMS: We report pathology findings from the first 10 years of the faecal-occult blood-based Northern Ireland Bowel Cancer Screening Programme, presenting summary data and trends in pathology diagnoses and clinicopathological features of screen-detected cancers. METHODS AND RESULTS: Data were analysed from a comprehensive polyp-level pathology database representing all endoscopy specimens from programme inception in 2010 until 2021. A total of 9800 individuals underwent 13 472 endoscopy procedures, yielding 25 967 pathology specimens and 32 119 diagnoses. Index specimen diagnoses (4.1%) and index colonoscopies (10.4%) yielded a diagnosis of colorectal cancer, representing 1045 cancers from 1020 individuals (25 with synchronous cancers). A further 13 index cancers were identified via computed tomography colonography; 65.3% of cancer diagnoses were in males; 41.7% were stage I, 23.1% stage II, 25.8% stage III and 1.8% stage IV (7.6% unstaged). Of 233 pT1 cancers diagnosed within local excision specimens, 79 (33.9%) had completion surgery. Ten-year trends showed a steady decline in the proportion of index colonoscopies that yielded a diagnosis of cancer (14.7% in year 1; 4.8% in year 11) or advanced colorectal polyp. There was a strong upward trend in diagnoses of sessile serrated lesions, which overtook hyperplastic polyps in proportions of total index diagnoses by the end of the study time-frame (8.7% compared to 8.5%). CONCLUSIONS: Over the first 10 years of a population colorectal cancer screening programme, 'real world' pathology data demonstrate success in the form of reduced diagnoses of cancer and advanced colorectal polyp with passage of successive screening rounds. Interesting trends with respect to serrated polyp diagnoses are also evident, probably related to pathologist and endoscopist behaviour.

Spatiotemporal immune atlas of the first clinical-grade, gene-edited pig-to-human kidney xenotransplant.

Pig-to-human xenotransplantation is rapidly approaching the clinical arena; however, it is unclear which immunomodulatory regimens will effectively control human immune responses to pig xenografts. We transplanted a gene-edited pig kidney into a brain-dead human recipient on pharmacologic immunosuppression and studied the human immune response to the xenograft using spatial transcriptomics and single-cell RNA sequencing. Human immune cells were uncommon in the porcine kidney cortex early after xenotransplantation and consisted of primarily myeloid cells. Both the porcine resident macrophages and human infiltrating macrophages expressed genes consistent with an alternatively activated, anti-inflammatory phenotype. No significant infiltration of human B or T cells into the porcine kidney xenograft was detected. Altogether, these findings provide proof of concept that conventional pharmacologic immunosuppression is sufficient to restrict infiltration of human immune cells into the xenograft early after compatible pig-to-human kidney xenotransplantation.

Change in Body Mass Index and Attributable Risk of New-Onset Hypertension Among Obese Living Kidney Donors.

OBJECTIVE: To examine whether body mass index (BMI) changes modify the association between kidney donation and incident hypertension. BACKGROUND: Obesity increases hypertension risk in both general and living kidney donor (LKD) populations. Donation-attributable risk in the context of obesity, and whether weight change modifies that risk, is unknown. METHODS: Nested case-control study among 1558 adult LKDs (1976-2020) with obesity (median follow-up: 3.6 years; interquartile range: 2.0-9.4) and 3783 adults with obesity in the Coronary Artery Risk Development in Young Adults (CARDIA) and Atherosclerosis Risk in Communities (ARIC) studies (9.2 y; interquartile range: 5.3-15.8). Hypertension incidence was compared by donor status using conditional logistic regression, with BMI change investigated for effect modification. RESULTS: Overall, LKDs and nondonors had similar hypertension incidence [incidence rate ratio (IRR): 1.16, 95% confidence interval (95% CI): 0.94-1.43, P =0.16], even after adjusting for BMI change (IRR: 1.25, 95% CI: 0.99-1.58, P =0.05). Although LKDs and nondonors who lost >5% BMI had comparable hypertension incidence (IRR: 0.78, 95% CI: 0.46-1.34, P =0.36), there was a significant interaction between donor and >5% BMI gain (multiplicative interaction IRR: 1.62, 95% CI: 1.15-2.29, P =0.006; relative excess risk due to interaction: 0.90, 95% CI: 0.24-1.56, P =0.007), such that LKDs who gained weight had higher hypertension incidence than similar nondonors (IRR: 1.83, 95% CI: 1.32-2.53, P <0.001). CONCLUSIONS: Overall, LKDs and nondonors with obesity had similar hypertension incidence. Weight stability and loss were associated with similar hypertension incidence by donor status. However, LKDs who gained >5% saw increased hypertension incidence versus similar nondonors, providing support for counseling potential LKDs with obesity on weight management postdonation.

Diabetes-free survival among living kidney donors and non-donors with obesity: A longitudinal cohort study.

BACKGROUND: Approval of living kidney donors (LKD) with end-stage kidney disease (ESKD) risk factors, such as obesity, has increased. While lifetime ESKD development data are lacking, the study of intermediate outcomes such as diabetes is critical for LKD safety. Donation-attributable diabetes risk among persons with obesity remains unknown. The purpose of this study was to evaluate 10-year diabetes-free survival among LKDs and non-donors with obesity. METHODS: This longitudinal cohort study identified adult, LKDs (1976-2020) from 42 US transplant centers and non-donors from the Coronary Artery Risk Development in Young Adults (1985-1986) and the Atherosclerosis Risk in Communities (1987-1989) studies with body mass index ≥30 kg/m2. LKDs were matched to non-donors on baseline characteristics (age, sex, race, body mass index, systolic and diastolic blood pressure) plus diabetes-specific risk factors (family history of diabetes, impaired fasting glucose, smoking history). Accelerated failure time models were utilized to evaluate 10-year diabetes-free survival. FINDINGS: Among 3464 participants, 1119 (32%) were LKDs and 2345 (68%) were non-donors. After matching on baseline characteristics plus diabetes-specific risk factors, 4% (7/165) LKDs and 9% (15/165) non-donors developed diabetes (median follow-up time 8.5 (IQR: 5.6-10.0) and 9.1 (IQR: 5.9-10.0) years, respectively). While not significant, LKDs were estimated to live diabetes-free 2 times longer than non-donors (estimate 1.91; 95% CI: 0.79-4.64, p = 0.15). CONCLUSIONS: LKDs with obesity trended toward living longer diabetes-free than non-donors with obesity, suggesting within the decade following donation there was no increased diabetes risk among LKDs. Further work is needed to evaluate donation-attributable diabetes risk long-term.

First clinical-grade porcine kidney xenotransplant using a human decedent model.

A radical solution is needed for the organ supply crisis, and the domestic pig is a promising organ source. In preparation for a clinical trial of xenotransplantation, we developed an in vivo pre-clinical human model to test safety and feasibility tenets established in animal models. After performance of a novel, prospective compatible crossmatch, we performed bilateral native nephrectomies in a human brain-dead decedent and subsequently transplanted two kidneys from a pig genetically engineered for human xenotransplantation. The decedent was hemodynamically stable through reperfusion, and vascular integrity was maintained despite the exposure of the xenografts to human blood pressure. No hyperacute rejection was observed, and the kidneys remained viable until termination 74 h later. No chimerism or transmission of porcine retroviruses was detected. Longitudinal biopsies revealed thrombotic microangiopathy that did not progress in severity, without evidence of cellular rejection or deposition of antibody or complement proteins. Although the xenografts produced variable amounts of urine, creatinine clearance did not recover. Whether renal recovery was impacted by the milieu of brain death and/or microvascular injury remains unknown. In summary, our study suggests that major barriers to human xenotransplantation have been surmounted and identifies where new knowledge is needed to optimize xenotransplantation outcomes in humans.

Outcomes of conservatively managed complex acetabular fractures in the frail and elderly one year post injury.

BACKGROUND: Acetabular fractures in the elderly are associated with high levels of morbidity and mortality. Despite advances in operative techniques, there remains a cohort of elderly, extremely frail patients with comminuted fractures who are considered unfit for surgery and are treated conservatively. We aim to assess mortality, mobility and radiological outcomes one-year post injury in this challenging cohort. METHODS: We performed a review of the regional Fracture Outcome and Research Database for patients over 65 with associated type acetabular fractures which were treated conservatively. We collected data on demographics, fracture classification, pre-injury mobility and habitation, and length of acute hospital stay. Mobility status, habitation, radiographic result and mortality were also recorded at one-year post injury. RESULTS: There were 49 patients with a mean age of 80 years. The mean estimated American Society of Anaesthesiologist (ASA) score was 3.1. 92% sustained a low energy injury, and the most common fracture pattern was anterior posterior hemi-transverse (84%). Mean acute hospital stay was 20 days and mortality was 24% at one year. 56% of patients maintained habitation in their own home and 35% returned to their premorbid level of mobility. Of the surviving patients, 30% had an 'excellent/good' reduction on x-ray at one year, 70% had a 'fair/poor' reduction. There was no correlation between fracture reduction and either one year mobility status or maintenance of mobility. CONCLUSIONS: The data confirms that conservatively managed complex acetabular fractures in the elderly, frail patient are associated with a significant reduction in mobility and living independence, a high level of mortality and poor radiological outcomes. IMPLICATIONS: Conservative management of this cohort is associated with poor outcomes and current operative solutions are unsuitable for this frail cohort of patients. Future developments should focus on minimising surgical insult and allowing weight bearing mobilisation to maximise the rehabilitation potential in this frail cohort.

Scalp ulceration: a rare manifestation of giant cell arteritis.

An 81-year-old woman presented with an enlarging, tender ulcer on her scalp over an 8-week period, attributing it to a prior graze with garden shears. C-reactive protein and erythrocyte sedimentation rate were elevated at 87.7 mg/L and 112 mm/hour, respectively. Incisional biopsies demonstrated ulceration and full thickness necrosis with no evidence of malignancy. Vasculitis was suggested as a likely cause of such extensive necrosis and subsequent temporal artery biopsy findings were consistent with giant cell arteritis. The patient was initially treated with high-dose oral prednisolone and achieved complete healing of the scalp necrosis within 12 months, with a gradual down-titration of steroid therapy thereafter. Scalp necrosis is a rare, potentially life-threatening complication of giant cell arteritis. This case highlights the importance of considering scalp necrosis as a manifestation of giant cell arteritis when assessing scalp ulceration. Prompt diagnosis and treatment can prevent significant morbidity and potential mortality.

Co-morbidities in Patients with a Hip Fracture.

Hip fractures usually occur in elderly patients who commonly have pre-existing medical problems or comorbidities. We retrospectively reviewed 100 patients admitted to our unit with a hip fracture to quantify their medical complexity. Age and comorbidity profile were used to determine an age-adjusted Charlson Co-morbidity Index (ACCI). The findings were then compared to 100 patients admitted under the care of the acute medical team. The patients in the fracture group were significantly older (p<0.0001), had significantly more co-morbidities (p<0.0001) and had a significantly greater predicted one-year mortality (p<0.0001). Cardiorespiratory disorders were the most common co-morbidities in the hip fracture group. We discuss our findings in combination with a review of the pertinent literature.

Donation approval among obese living kidney donor candidates: The impact of metabolic syndrome.

BACKGROUND: The scarcity of organs available for transplantation has increased attempts to augment transplantation by utilizing obese living kidney donors. The literature has suggested that these donors have increased risks postdonation. Not surprising, the threshold for living kidney donor approval among obese persons is typically higher and the process more costly. Therefore, a screening tool to predict the likelihood of approval among obese living kidney donor candidates was created. METHODS: A single-center retrospective study was performed among obese (body mass index ≥ 30 kg/m2) living kidney donor candidates evaluated in clinic (January 1, 2012, to December 31, 2017). Approved candidates were compared with those not approved using multivariable logistic regression, and a prediction tool was generated. RESULTS: Among 389 obese living kidney donor candidates, there were no significant differences in sex or race and ethnicity by approval status. However, nonapproved candidates had a higher prevalence of metabolic syndrome. In the prediction model, glucose impairment and hypertension were most predictive of nonapproval. CONCLUSION: Among obese living kidney donor candidates, several metabolic syndrome components were associated with decreased odds of approval. This tool may serve as a useful initial screening for obese living kidney donor candidates, permitting more cost-effective evaluation processes. The tool could also be used to promote expeditious interventions in the preclinical setting, including weight management programs, to improve the likelihood of donation and postdonation outcomes.

Adult Granulosa Cell Tumor With High-grade Transformation: Report of a Series With FOXL2 Mutation Analysis.

Adult granulosa cell tumor (AGCT) is a low-grade malignant neoplasm with a significant propensity for late recurrence and metastasis. Almost all AGCTs are composed of cells with bland nuclear features and even when these tumors recur or metastasize, the nuclear features are almost always low-grade. We report 5 cases of AGCT in patients aged 37 to 88 years composed of areas of typical AGCT with low-grade morphology admixed with areas of high-grade morphology, with marked nuclear atypia, often with bizarre multinucleate cells and high mitotic activity; this is the first reported series of high-grade transformation in AGCTs. The high-grade areas often morphologically closely resembled juvenile granulosa cell tumor with abundant eosinophilic cytoplasm, significant mitotic activity, and intermediate sized follicles. Four cases were FIGO stage IA at diagnosis and 1 was stage IIIC with omental involvement. FOXL2 mutation analysis of both the morphologically low-grade and high-grade areas in 4 of 5 cases confirmed the presence of missense point mutation, c.402C>G, p.(Cys134Trp), providing conclusive evidence that the high-grade component represents transformation of typical AGCT rather than the coexistence of another sex cord-stromal tumor, such as juvenile granulosa cell tumor, which has been suggested for such neoplasms. In 3 of 4 cases where immunohistochemistry was undertaken, there was a striking difference between the p53 staining in the low-grade and high-grade components with wild-type staining in the former and diffuse mutation-type immunoreactivity in the latter, suggesting that TP53 mutation is likely to play a role in high-grade transformation. TP53 mutation analysis covering exons 4 to 10 was undertaken in 4 cases and TP53 mutations were identified in the high-grade component of 2 of the cases. In 1 case, there was diffuse block-type p16 staining in the high-grade component. Follow-up in the 4 stage IA neoplasms revealed no evidence of tumor recurrence in 3 (6 to 9 mo follow-up) while the other patient developed mediastinal, peritoneal, and pulmonary metastasis 17 months after diagnosis. High-grade transformation is uncommon in AGCTs and given that one of our cases was advanced stage at diagnosis, another exhibited widespread metastasis within a short period and there have been occasional case reports of aggressive behavior in AGCTs with high-grade transformation, this event may herald an aggressive clinical course.