Single-center Outcomes After Liver Transplantation With SARS-CoV-2-Positive Donors: An Argument for Increased Utilization.

Background: The COVID-19 pandemic has led to an increase in SARS-CoV-2-test positive potential organ donors. The benefits of life-saving liver transplantation (LT) must be balanced against the potential risk of donor-derived viral transmission. Although emerging evidence suggests that the use of COVID-19-positive donor organs may be safe, granular series thoroughly evaluating safety are still needed. Results of 29 consecutive LTs from COVID-19-positive donors at a single center are presented here. Methods: A retrospective cohort study of LT recipients between April 2020 and December 2022 was conducted. Differences between recipients of COVID-19-positive (n = 29 total; 25 index, 4 redo) and COVID-19-negative (n = 472 total; 454 index, 18 redo) deceased donor liver grafts were compared. Results: COVID-19-positive donors were significantly younger (P = 0.04) and had lower kidney donor profile indices (P = 0.04) than COVID-19-negative donors. Recipients of COVID-19-positive donor grafts were older (P = 0.04) but otherwise similar to recipients of negative donors. Donor SARS-CoV-2 infection status was not associated with a overall survival of recipients (hazard ratio, 1.11; 95% confidence interval, 0.24-5.04; P = 0.89). There were 3 deaths among recipients of liver grafts from COVID-19-positive donors. No death seemed virally mediated because there was no qualitative association with peri-LT antispike antibody titers, post-LT prophylaxis, or SARS-CoV-2 variants. Conclusions: The utilization of liver grafts from COVID-19-positive donors was not associated with a decreased overall survival of recipients. There was no suggestion of viral transmission from donor to recipient. The results from this large single-center study suggest that COVID-19-positive donors may be used safely to expand the deceased donor pool.

Effect of a Hispanic outreach program on referral and liver transplantation volume at a single center.

BACKGROUND: Although Hispanic patients have high rates of end-stage liver disease and liver cancer, for which liver transplantation (LT) offers the best long-term outcomes, they are less likely to receive LT. Studies of end-stage renal disease patients and kidney transplant candidates have shown that targeted, culturally relevant interventions can increase the likelihood of Hispanic patients receiving kidney transplant. However, similar interventions remain largely unstudied in potential LT candidates. METHODS: Referrals to a single center in Texas with a large Hispanic patient population were compared before (01/2018-12/2019) and after (7/2021-6/2023) the implementation of a targeted outreach program. Patient progress toward LT, reasons for ineligibility, and differences in insurance were examined between the two eras. RESULTS: A greater proportion of Hispanic patients were referred for LT after the implementation of the outreach program (23.2% vs 26.2%, p = 0.004). Comparing the pre-outreach era to the post-outreach era, more Hispanic patients achieved waitlisting status (61 vs 78, respectively) and received a LT (971 vs 82, respectively). However, the proportion of Hispanic patients undergoing LT dropped from 30.2% to 20.3%. In the post-outreach era, half of the Hispanic patients were unable to get LT for financial reasons (112, 50.5%). CONCLUSIONS: A targeted outreach program for Hispanic patients with end-stage liver disease effectively increased the total number of Hispanic LT referrals and recipients. However, many of the patients who were referred were ineligible for LT, most frequently for financial reasons. These results highlight the need for additional research into the most effective ways to ameliorate financial barriers to LT in this high-need community.

Surgical techniques for robotic right donor hepatectomy, part 2: robotic parenchymal transection and bile duct division.

Robotic surgery is emerging as a feasible minimally invasive approach for donor hepatectomy at specialized centers. The aim of this article is to systematically describe the surgical techniques for robotic parenchymal transection and bile duct division in right donor hepatectomy. The setup of the robotic arms, methods of parenchymal transection using robotic instruments, and right hepatic duct division with the aid of indocyanine green dye are detailed, along with the pearls and pitfalls of these two parts of the operation.

Surgical techniques for robotic right donor hepatectomy, part 1: robotic hilar dissection and right lobe mobilization.

Robotic surgery is emerging as a feasible minimally invasive approach for donor hepatectomy at specialized centers. The aim of this article is to systematically describe the surgical techniques for robotic hilar dissection and right lobe mobilization in right donor hepatectomy. The setup of the robotic arms, the dissection of inflow vessels and retrohepatic inferior vena cava, and the pearls and pitfalls of these two parts of the operation are detailed.

Transplant Oncology: An Emerging Discipline of Cancer Treatment.

Transplant oncology is an emerging concept of cancer treatment with a promising prospective outcome. The applications of oncology, transplant medicine, and surgery are the core of transplant oncology to improve patients' survival and quality of life. The main concept of transplant oncology is to radically cure cancer by removing the diseased organ and replacing it with a healthy one, aiming to improve the survival outcomes and quality of life of cancer patients. Subsequently, it seeks to expand the treatment options and research for hepatobiliary malignancies, which have seen significantly improved survival outcomes after the implementation of liver transplantation (LT). In the case of colorectal cancer (CRC) in the transplant setting, where the liver is the most common site of metastasis of patients who are considered to have unresectable disease, initial studies have shown improved survival for LT treatment compared to palliative therapy interventions. The indications of LT for hepatobiliary malignancies have been slowly expanded over the years beyond Milan criteria in a stepwise manner. However, the outcome improvements and overall patient survival are limited to the specifics of the setting and systematic intervention options. This review aims to illustrate the representative concepts and history of transplant oncology as an emerging discipline for the management of hepatobiliary malignancies, in addition to other emerging concepts, such as the uses of immunotherapy in a peri-transplant setting as well as the use of circulating tumor DNA (ctDNA) for surveillance post-transplantation.

Role of Screening Lung Function Tests in a Routine Health Checkup.

Background and objectives The lung function test is a gold standard, guideline-recommended test to detect obstructive airway diseases like asthma and COPD. It is of considerable value in detecting the presence and severity of airflow obstruction in patients with respiratory symptoms. However, the role of spirometry in a routine health checkup is controversial. Spirometry, when used in routine health checkup settings as a case-finding tool for all adults with persistent respiratory symptoms or having a history of exposure to risk factors, is likely to label a relatively large proportion of individuals as diseased with airflow obstruction. Conversely, spirometry is normal in a relatively large percentage of adults who report respiratory symptoms including dyspnea, the respiratory symptom having the greatest impact on quality of life. The objective of this study is to determine the utility of spirometry as a screening test to detect airflow obstruction in otherwise healthy subjects undergoing a routine health checkup. Methods This observational study was conducted with 538 health checkup individuals aged 18 and over. A brief history was taken prior to the test. Lung function tests were performed and interpreted as per the Global Initiative for Chronic Obstructive Lung Disease criteria. The anthropometric and spirometric data obtained were compared to other population-based spirometric studies to compare the prevalence of airflow limitation, the risk factors, and smoking history. Results Of the total 538 subjects incorporated in the study, 305 (57%) were males and 233 (43%) were females aged between 18 to 80 years with a mean age of 45 years. The male-to-female ratio was 1.3:1 with a mean BMI of 25.9. The overall yield from lung function tests in detecting airflow obstruction was 63 subjects (11.7%), of which 36 (11.8%) were males and 27 (11.5%) were females. Seventy-three subjects (13.5%) were classified as having a small airway obstruction, of which 34 were males (46.6%), and 39 were females (53.4%). The distribution of airflow obstruction by age was with eight subjects (5.4%) in the 18-35 group, 21 subjects (7.8%) in the 36-55 group, and 34 (25%) in the elderly (>55) age group. Although overall smoking history showed no significant association with developing airflow obstruction, significant association with smoking was found in the elderly (>55) age group. Interpretation and conclusions The results of the study suggest that lung function tests should be included in routine health checkups in the subset of individuals greater than 35 years of age with or without a history of smoking, in all age groups with a family history of asthma, in individuals with respiratory symptoms and in individuals greater than 55 years of age with a moderate history of smoking.

Validation of a multidisciplinary virtual reality (VR) robotic surgical curriculum.

The objective is to identify whether trainees demonstrate improvement in a standardized knot-tying task as assessed by Global Evaluative Assessment of Robotic Skills (GEARS) score after completion of a virtual reality (VR) robotic curriculum. An IRB-exempt prospective study was conducted with surgical trainees from August 2021 to February 2023. Participants initially performed a baseline robotic suturing task in which they were instructed to tie interrupted square knots in 10 min. Participants then completed a virtual reality simulation curriculum involving 23 exercises until they achieved 90% proficiency on all tasks. Participants then repeated the suturing task. Pre- and post-curriculum suturing tasks were recorded, de-identified, and scored by expert graders using a GEARS score. Trainees from three academic centers were invited to participate. Medical students (MS1-MS3) and surgical residents from gynecology, urology, and general surgery were invited to participate. Twenty-five trainees completed the pre-curriculum suturing task, the VR curriculum, and the post-curriculum suturing task. Trainees demonstrated significant improvement in their post-test GEARS score by 2.43 points (p < 0.05) and were able to tie three additional knots within 10 min after completion of the curriculum (p < 0.05). Trainees also demonstrated a faster time to complete first knot (114 s improvement, p < 0.05) after completion of the curriculum. All participants agreed or strongly agreed that completion of the robotic curriculum helped them feel more comfortable using the robotic console, and improved their robotic surgical skills. Surgical trainees and medical students with limited prior robotic surgical experience demonstrated objective improvement after completion of a standardized VR curriculum.

Well-Differentiated Neuroendocrine Tumors of the Appendix in Children and Adolescents: A Clinicopathologic Study.

BACKGROUND AND AIMS: Pediatric neuroendocrine tumors (NET) of the GI tract are rare and appendiceal NET are typically incidental. Few studies have been done in the pediatric population and practice guidelines are mainly based on adult data. There are currently no diagnostic studies specific for NET. Our study aimed to identify clinical, radiological, and pathological findings in pediatric appendiceal NET, test criteria for follow up surgical treatment, review potential prognostic pathological findings, and possible pre-operative diagnostic radiological studies. MATERIALS AND METHODS: A retrospective data search was conducted for well-differentiated NET of the appendix in patients ≤21 years between 1/1/2003 and 7/1/2022. Available clinical, radiologic, pathological, and follow-up information was recorded. RESULTS: Thirty-seven patients with appendiceal NET were identified. No masses were reported in the patients who underwent presurgical imaging. Appendectomy samples showed NET (0.2->4 cm), most located in the tip. Most cases were WHO G1 (34/37), with negative margins (n = 25). Sixteen cases extended to the subserosa/mesoappendix (pT3). Lymphovascular (6), perineural (2), and both lymphovascular and perineural invasion were also noted (2). The specified tumor stages were pT1 (10/37), pT3 (16/37), and pT4 (4/37). Patients who underwent laboratory testing for chromogranin A (20) and urine 5HIAA (11) had normal limits. Subsequent surgical resection was recommended in 13 cases and performed in 11. To date, all patients have no recurrent or additional metastatic disease. CONCLUSIONS: Our study showed that all pediatric well-differentiated appendiceal NET were incidentally found as part of acute appendicitis management. Most NET were localized with low-grade histology. Our small cohort support the previously suggested management guidelines with follow up resection in certain cases. Our radiologic review didn't identify a best modality for NET. Comparing cases with and without metastatic disease, no tumors under 1 cm had metastasis, but serosal and perineural invasion along with G2 status were associated with metastasis in our limited study.

An Sfi1-like centrin-interacting centriolar plaque protein affects nuclear microtubule homeostasis.

Malaria-causing parasites achieve rapid proliferation in human blood through multiple rounds of asynchronous nuclear division followed by daughter cell formation. Nuclear divisions critically depend on the centriolar plaque, which organizes intranuclear spindle microtubules. The centriolar plaque consists of an extranuclear compartment, which is connected via a nuclear pore-like structure to a chromatin-free intranuclear compartment. Composition and function of this non-canonical centrosome remain largely elusive. Centrins, which reside in the extranuclear part, are among the very few centrosomal proteins conserved in Plasmodium falciparum. Here we identify a novel centrin-interacting centriolar plaque protein. Conditional knock down of this Sfi1-like protein (PfSlp) caused a growth delay in blood stages, which correlated with a reduced number of daughter cells. Surprisingly, intranuclear tubulin abundance was significantly increased, which raises the hypothesis that the centriolar plaque might be implicated in regulating tubulin levels. Disruption of tubulin homeostasis caused excess microtubules and aberrant mitotic spindles. Time-lapse microscopy revealed that this prevented or delayed mitotic spindle extension but did not significantly interfere with DNA replication. Our study thereby identifies a novel extranuclear centriolar plaque factor and establishes a functional link to the intranuclear compartment of this divergent eukaryotic centrosome.

Visualization of erythrocyte stasis in the living human eye in health and disease.

Blood cells trapped in stasis have been reported within the microcirculation, but their relevance to health and disease has not been established. In this study, we introduce an in vivo imaging approach that reveals the presence of a previously-unknown pool of erythrocytes in stasis, located within capillary segments of the CNS, and present in 100% of subjects imaged. These results provide a key insight that blood cells pause as they travel through the choroidal microvasculature, a vascular structure that boasts the highest blood flow of any tissue in the body. Demonstration of clinical utility using deep learning reveals that erythrocyte stasis is altered in glaucoma, indicating the possibility of more widespread changes in choroidal microvascular than previously realized. The ability to monitor the choroidal microvasculature at the single cell level may lead to novel strategies for tracking microvascular health in glaucoma, age-related macular degeneration, and other neurodegenerative diseases.

Retinal hemorrhages in abusive head trauma with atraumatic neuroimaging.

We report 3 cases of suspected abusive head trauma with retinal hemorrhages on fundus examination and neuroimaging findings not necessarily suggestive of shaking injury. Previous studies have suggested that retinal hemorrhages are rare in patients without neuroimaging abnormalities. These cases demonstrate some common features (rib fractures, developmental delay, and history of abuse) that may increase suspicion for abusive head trauma. Our findings suggest a potential role for ophthalmic consultation in scenarios with high clinical suspicion for abusive head trauma without definitive neuroimaging evidence of head injury. The nonspecific neuroimaging features of these 3 cases highlight the importance of interpreting cases with global clinical context.

Developing basic robotic skills using virtual reality simulation and automated assessment tools: a multidisciplinary robotic virtual reality-based curriculum using the Da Vinci Skills Simulator and tracking progress with the Intuitive Learning platform.

This study sought to develop basic robotic surgical skills among surgical trainees across multiple specialties using a VR-based curriculum and provided objective, on-demand, automated assessments using the Intuitive Learning platform. This curriculum was developed using the Da Vinci Skills Simulator and included 24 exercises. A pre-test and post-test were required for completion of the curriculum. Scores > 90 on individual exercises and the post-test were required for successful completion. The Intuitive learning platform provided automated performance metrics and tracked trainee progression. The curriculum was implemented and data collected over a 12-month period. 21 trainees completed the entire curriculum. Post-test scores were significantly higher than pre-test scores and trainees reported improvement in their robotic skills after curriculum completion. A comparison based on training level revealed that junior residents had significantly lower number of attempts per exercise, fewer penalties, and higher completion scores when compared to senior residents and fellows. Individual exercise analysis demonstrated that exercises, such as 'Three-Arm Relay' and 'Ring Rollercoaster', required the longest time and most attempts to achieve a passing score. The 'Energy Pedals' and 'Knot Tying' skills were the least-utilized skills addressed in the curriculum. Virtual reality-based curriculums using the Intuitive Learning platform can be standardized across multiple specialties allowing for the development of basic robotic skills, shared interdisciplinary surgical education, and provides powerful objective and automated performance metrics of trainees.

Secretory Carcinoma in Children and Young Adults: A Case Series.

Secretory carcinoma (SC), previously known as mammary analogue secretory carcinoma, is a rare salivary gland neoplasm that typically presents as a slow-growing painless lesion in the head and neck. SC occurs mainly in adults but has been described in children with the youngest reported patient diagnosed at five years of age. In children the gender distribution has been reported as female to male ratio of 1:1.2. SC is generally considered a low-grade malignancy with characteristic morphological features and immunological profile. SC also harbors ETV6-NTRK3 fusion (t(12;15)(p13:q25)). Surgical resection with or without lymph node dissection is the standard treatment, with generally favorable clinical outcomes. Here we present a single institution case series of six patients (ages 9-21) with SC and a review of the previously described pediatric cases. Our small series showed male predominance in pediatric patients with predominantly low-grade and stage tumors. All cases underwent complete surgical resections and when follow up is available there was no evidence of recurrences or metastases. To the best of our knowledge, this is the only SC case series comprised exclusively of pediatric and youth patients.

Conjunctival Melanocytic Lesions.

CONTEXT.­: Conjunctival melanocytic lesions consist of a variety of neoplastic and nonneoplastic conditions. These include benign processes such as primary intraepithelial hypermelanosis and melanocytic hyperplasia, secondary forms of intraepithelial hypermelanosis and melanocytic hyperplasia, melanocytic nevi, melanocytic proliferations with malignant potential, and melanoma. OBJECTIVE.­: To provide a concise yet comprehensive resource regarding the histopathologic diagnosis of conjunctival melanocytic lesions. We aim to detail and clarify the numerous classification schemes that exist for junctional melanocytic proliferations of the conjunctiva (known as primary acquired melanosis or PAM; also termed conjunctival melanocytic intraepithelial neoplasia or C-MIN). Although not uniformly adopted, C-MIN is classified by using a numeric system based on a defined set of criteria. A less complex scheme (conjunctival melanocytic intraepithelial lesion or CMIL) has recently been proposed by the World Health Organization. Additionally, we aim to update the reader regarding molecular features and prognostic indicators. DATA SOURCES.­: Peer-reviewed literature and archived cases for illustration. CONCLUSIONS.­: Accurate histologic classification is essential, as PAM/C-MIN/CMILs that have a significant potential to progress to invasive melanoma may be clinically indistinguishable from low-risk lesions. Conjunctival melanoma (CM) more closely resembles cutaneous melanoma in terms of its pathogenesis and molecular features, compared to melanoma arising at other mucosal sites or to uveal melanoma. Depth of invasion and ulceration status, among other factors, have emerged as important prognostic indicators in CM. Sentinel lymph node biopsy may provide further prognostic information. Lastly, integration of pathologic and clinical findings is essential at this anatomically sensitive location to determine appropriate clinical management.

Co-chaperone involvement in knob biogenesis implicates host-derived chaperones in malaria virulence.

The pathology associated with malaria infection is largely due to the ability of infected human RBCs to adhere to a number of receptors on endothelial cells within tissues and organs. This phenomenon is driven by the export of parasite-encoded proteins to the host cell, the exact function of many of which is still unknown. Here we inactivate the function of one of these exported proteins, PFA66, a member of the J-domain protein family. Although parasites lacking this protein were still able to grow in cell culture, we observed severe defects in normal host cell modification, including aberrant morphology of surface knobs, disrupted presentation of the cytoadherence molecule PfEMP1, and a total lack of cytoadherence, despite the presence of the knob associated protein KAHRP. Complementation assays demonstrate that an intact J-domain is required for recovery to a wild-type phenotype and suggest that PFA66 functions in concert with a HSP70 to carry out host cell modification. Strikingly, this HSP70 is likely to be of host origin. ATPase assays on recombinant protein verify a functional interaction between PFA66 and residual host cell HSP70. Taken together, our data reveal a role for PFA66 in host cell modification, strongly implicate human HSP70s as being essential in this process and uncover a new KAHRP-independent molecular factor required for correct knob biogenesis.

An extended DNA-free intranuclear compartment organizes centrosome microtubules in malaria parasites.

Proliferation of Plasmodium falciparum in red blood cells is the cause of malaria and is underpinned by an unconventional cell division mode, called schizogony. Contrary to model organisms, P. falciparum replicates by multiple rounds of nuclear divisions that are not interrupted by cytokinesis. Organization and dynamics of critical nuclear division factors remain poorly understood. Centriolar plaques, the centrosomes of P. falciparum, serve as microtubule organizing centers and have an acentriolar, amorphous structure. The small size of parasite nuclei has precluded detailed analysis of intranuclear microtubule organization by classical fluorescence microscopy. We apply recently developed super-resolution and time-lapse imaging protocols to describe microtubule reconfiguration during schizogony. Analysis of centrin, nuclear pore, and microtubule positioning reveals two distinct compartments of the centriolar plaque. Whereas centrin is extranuclear, we confirm by correlative light and electron tomography that microtubules are nucleated in a previously unknown and extended intranuclear compartment, which is devoid of chromatin but protein-dense. This study generates a working model for an unconventional centrosome and enables a better understanding about the diversity of eukaryotic cell division.

How Many Is Enough? - Challenges of Multinucleated Cell Division in Malaria Parasites.

Regulating the number of progeny generated by replicative cell cycles is critical for any organism to best adapt to its environment. Classically, the decision whether to divide further is made after cell division is completed by cytokinesis and can be triggered by intrinsic or extrinsic factors. Contrarily, cell cycles of some species, such as the malaria-causing parasites, go through multinucleated cell stages. Hence, their number of progeny is determined prior to the completion of cell division. This should fundamentally affect how the process is regulated and raises questions about advantages and challenges of multinucleation in eukaryotes. Throughout their life cycle Plasmodium spp. parasites undergo four phases of extensive proliferation, which differ over three orders of magnitude in the amount of daughter cells that are produced by a single progenitor. Even during the asexual blood stage proliferation parasites can produce very variable numbers of progeny within one replicative cycle. Here, we review the few factors that have been shown to affect those numbers. We further provide a comparative quantification of merozoite numbers in several P. knowlesi and P. falciparum parasite strains, and we discuss the general processes that may regulate progeny number in the context of host-parasite interactions. Finally, we provide a perspective of the critical knowledge gaps hindering our understanding of the molecular mechanisms underlying this exciting and atypical mode of parasite multiplication.

Plasmacytoid urothelial carcinoma: a rapid autopsy case report with unique clinicopathologic and genomic profile.

BACKGROUND: Rapid ("warm") autopsies of patients with advanced metastatic cancer provide important insight into the natural history, pathobiology and histomorphology of disease in treatment-resistant tumors. Plasmacytoid urothelial carcinoma (PUC) is a rare variant of urothelial carcinoma characterized by neoplastic cells morphologically resembling plasma cells. PUC is typically aggressive, high-stage at presentation, and associated with poor outcomes. Recurrence is common in PUC, with the majority of recurrences occurring in the peritoneum. CASE PRESENTATION: Here, we report rapid autopsy findings from a patient with recurrent PUC. The patient had persistent pain after cystoprostatectomy, although initial post-operative imaging showed no evidence of disease. Imaging obtained shortly before his death showed only subtle growth along vascular tissue planes; however, extensive disease was seen on autopsy. Plasmacytoid tumor cells formed sheets involving many serosal surfaces. Molecular interrogation confirmed a mutation in CDH1 exon 12 leading to early truncation of the CDH1 protein in the tumor cells. CONCLUSIONS: The sheet-like growth pattern of PUC makes early phases of disease spread much more difficult to capture on cross-sectional imaging. Alternative forms of surveillance may be required for detection of recurrent PUC, and providers may need to treat based on symptoms and clinical suspicion.

Immunofluorescence staining protocol for STED nanoscopy of Plasmodium-infected red blood cells.

Immunofluorescence staining is the key technique for visualizing organization of endogenous cellular structures in single cells. Labeling and imaging of blood stage Plasmodium falciparum has always been challenging since it is a small intracellular parasite. A widely-used standard for parasite immunofluorescence is fixation in suspension with addition of minute amounts of glutaraldehyde to the paraformaldehyde-based solution. While this maintains red blood cell integrity, it has been postulated that antigenicity of the parasite proteins was, if at all, only slightly reduced. Here we show the deleterious effect that even these small quantities of glutaraldehyde can have on immunofluorescence staining quality and present an alternative cell seeding protocol that allows fixation with only paraformaldehyde. The highly improved signal intensity and staining efficiency enabled us to carry out RescueSTED nanoscopy on microtubules and nuclear pores and describe their organization in greater detail throughout the blood stage cycle.