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Despite the growing use of temporary mechanical circulatory support (tMCS), little data exists to inform management and weaning of these devices. We performed an online survey among cardiac intensive care unit directors in North America to examine current practices in the management of patients treated with intraaortic balloon pump and Impella. We received responses from 84% of surveyed centers (n=37). Our survey focused on three key aspects of daily management: 1. Hemodynamic monitoring; 2. Hemocompatibility; and 3. Weaning and removal. We found substantial variability surrounding all three areas of care. Our findings highlight the need for consensus around practices associated with improved outcomes in patients treated with tMCS. [ABSTRACT FROM AUTHOR]

Risk stratification has potential to guide triage and decision-making in cardiogenic shock (CS). We assessed the prognostic performance of the IABP-SHOCK II score, derived in Europe for acute myocardial infarct-related CS (AMI-CS), in a contemporary North American cohort, including different CS phenotypes. The critical care cardiology trials network (CCCTN) coordinated by the TIMI study group is a multicenter network of cardiac intensive care units (CICU). Participating centers annually contribute ≥2 months of consecutive medical CICU admissions. The IABP-SHOCK II risk score includes age > 73 years, prior stroke, admission glucose > 191 mg/dl, creatinine > 1.5 mg/dl, lactate > 5 mmol/l, and post-PCI TIMI flow grade < 3. We assessed the risk score across various CS etiologies. Of 17,852 medical CICU admissions 5,340 patients across 35 sites were admitted with CS. In patients with AMI-CS (n = 912), the IABP-SHOCK II score predicted a >3-fold gradient in in-hospital mortality (low risk = 26.5%, intermediate risk = 52.2%, high risk = 77.5%, P <.0001; c-statistic = 0.67; Hosmer-Lemeshow P =.79). The score showed a similar gradient of in-hospital mortality in patients with non-AMI-related CS (n = 2,517, P <.0001) and mixed shock (n = 923, P <.001), as well as in left ventricular (<0.0001), right ventricular (P =.0163) or biventricular (<0.0001) CS. The correlation between the IABP-SHOCK II score and SOFA was moderate (r2 = 0.17) and the IABP-SHOCK II score revealed a significant risk gradient within each SCAI stage. In an unselected international multicenter registry of patients admitted with CS, the IABP- SHOCK II score only moderately predicted in-hospital mortality in a broad population of CS regardless of etiology or irrespective of right, left, or bi-ventricular involvement. [ABSTRACT FROM AUTHOR]

Metastatic melanoma of the breast is rare, and demonstrates nonspecific imaging findings which may overlap with both benign and malignant pathology.1–3 Immunohistochemical stains are important to confirm the diagnosis, particularly combining S100, a sensitive marker for melanoma, with more specific tumor markers such as Melan-A and HMB-45, and lack of cytokeratin staining.4–7 We present a case of a 64-year-old female who presented for diagnostic imaging of a palpable abnormality in her right breast, with medical history notable for previously excised cutaneous melanoma, recent COVID-19 vaccination, and significant family history of breast cancer. Diagnostic mammogram of the right breast demonstrated a circumscribed mass in the lower inner quadrant corresponding to the area of palpable concern, as well as an additional non-palpable circumscribed mass in the lower inner quadrant. Targeted right breast ultrasound demonstrated corresponding circumscribed cystic versus solid masses as well as a morphologically abnormal right axillary lymph node. Pathologic results after tissue sampling of the two right breast masses and right axillary lymph node all yielded metastatic melanoma. • Metastatic melanoma of the breast is rare and carries a poor prognosis. • Its clinical and imaging features are nonspecific and may overlap with both benign and malignant pathology. • A high index of suspicion, prompt tissue sampling, and immunohistochemical staining are imperative to confirm the diagnosis. [ABSTRACT FROM AUTHOR]

Background: Acute heart failure (HF) is an important complication of coronavirus disease 2019 (COVID-19) and has been hypothesized to relate to inflammatory activation.Methods: We evaluated consecutive intensive care unit (ICU) admissions for COVID-19 across 6 centers in the Critical Care Cardiology Trials Network, identifying patients with vs without acute HF. Acute HF was subclassified as de novo vs acute-on-chronic, based on the absence or presence of prior HF. Clinical features, biomarker profiles and outcomes were compared.Results: Of 901 admissions to an ICU due to COVID-19, 80 (8.9%) had acute HF, including 18 (2.0%) with classic cardiogenic shock (CS) and 37 (4.1%) with vasodilatory CS. The majority (n = 45) were de novo HF presentations. Compared to patients without acute HF, those with acute HF had higher cardiac troponin and natriuretic peptide levels and similar inflammatory biomarkers; patients with de novo HF had the highest cardiac troponin levels. Notably, among patients critically ill with COVID-19, illness severity (median Sequential Organ Failure Assessment, 8 [IQR, 5-10] vs 6 [4-9]; P = 0.025) and mortality rates (43.8% vs 32.4%; P = 0.040) were modestly higher in patients with vs those without acute HF.Conclusions: Among patients critically ill with COVID-19, acute HF is distinguished more by biomarkers of myocardial injury and hemodynamic stress than by biomarkers of inflammation. [ABSTRACT FROM AUTHOR]

Background: Heart failure-related cardiogenic shock (HF-CS) accounts for an increasing proportion of cases of CS in contemporary cardiac intensive care units. Whether the chronicity of HF identifies distinct clinical profiles of HF-CS is unknown.Methods and Results: We evaluated admissions to cardiac intensive care units for HF-CS in 28 centers using data from the Critical Care Cardiology Trials Network registry (2017-2020). HF-CS was defined as CS due to ventricular failure in the absence of acute myocardial infarction and was classified as de novo vs acute-on-chronic based on the absence or presence of a prior diagnosis of HF, respectively. Clinical features, resource use, and outcomes were compared among groups. Of 1405 admissions with HF-CS, 370 had de novo HF-CS (26.3%), and 1035 had acute-on-chronic HF-CS (73.7%). Patients with de novo HF-CS had a lower prevalence of hypertension, diabetes, coronary artery disease, atrial fibrillation, and chronic kidney disease (all P < 0.01). Median Sequential Organ Failure Assessment (SOFA) scores were higher in those with de novo HF-CS (8; 25th-75th: 5-11) vs acute-on-chronic HF-CS (6; 25th-75th: 4-9, P < 0.01), as was the proportion of Society of Cardiovascular Angiography and Intervention (SCAI) shock stage E (46.1% vs 26.1%, P < 0.01). After adjustment for clinical covariates and preceding cardiac arrest, the risk of in-hospital mortality was higher in patients with de novo HF-CS than in those with acute-on-chronic HF-CS (adjusted hazard ratio 1.36, 95% confidence interval 1.05-1.75, P = 0.02).Conclusions: Despite having fewer comorbidities, patients with de novo HF-CS had more severe shock presentations and worse in-hospital outcomes. Whether HF disease chronicity is associated with time-dependent compensatory adaptations, unique pathobiological features and responses to treatment in patients presenting with HF-CS warrants further investigation. [ABSTRACT FROM AUTHOR]

This consensus statement emerges from collaborative efforts among leading figures in critical care cardiology throughout the United States, who met to share their collective expertise on issues faced by those active in or pursuing contemporary critical care cardiology education. The panel applied fundamentals of adult education and curriculum design, reviewed requisite training necessary to provide high-quality care to critically ill patients with cardiac pathology, and devoted attention to a purposeful approach emphasizing diversity, equity, and inclusion in developing this nascent field. The resulting paper offers a comprehensive guide for current trainees, with insights about the present landscape of critical care cardiology while highlighting issues that need to be addressed for continued advancement. By delineating future directions with careful consideration and intentionality, this Expert Panel aims to facilitate the continued growth and maturation of critical care cardiology education and practice. • CCC is a burgeoning specialty that requires advanced training. • Critical care training for a critical care cardiologist should be no fewer than 12 months. • Standardization of training goals and competencies are next steps for developing the CCC field. [ABSTRACT FROM AUTHOR]

Diacylglycerol O-acyltransferase 1 deficiency is a recently discovered, rare congenital diarrheal disorder. We report 2 patients with newly described pathogenic mutations in diacylglycerol O-acyltransferase 1 with compound heterozygous inheritance and unusual phenotypes. This included a macrophage activation syndrome-like response seen in one patient, ameliorated with low dietary fat. [ABSTRACT FROM AUTHOR]

Background: The prevalence of renal disease in cardiac intensive care units (CICUs) is increasing, but little is known about the utilization, concurrent therapies, and outcomes of patients requiring acute renal replacement therapy (RRT) in this specialized environment.Methods: In the Critical Care Cardiology Trials Network, 16 centers submitted data on CICU admissions including acute RRT (defined as continuous renal replacement therapy and/or acute intermittent dialysis).Results: Among 2,985 admissions, 178 (6.0%; interhospital range 1.0%-16.0%) received acute RRT. Patients receiving RRT, versus not, were more commonly admitted for cardiogenic shock (15.7% vs 4.2%, P < .01), cardiac arrest (9.6% vs 3.7%, P < .01), and acute general medical diagnoses (10.7% vs 5.8%, P < .01), whereas acute coronary syndromes (16.9% vs 32.1%, P < .01) were less frequent. Variables independently associated with acute RRT included diabetes, heart failure, liver disease, severe valvular disease, shock, cardiac arrest, hypertension, and younger age. In patients receiving acute RRT, versus not, advanced therapies including mechanical ventilation (55.6% vs 18.0%), vasoactive support (73.0% vs 35.2%), invasive hemodynamic monitoring (59.6% vs 29.2%), and mechanical circulatory support (27.5% vs 8.4%) were more common. Acute RRT was associated with higher in-hospital mortality (42.1% vs 9.3%, adjusted odds ratio 3.74, 95% CI, 2.52-5.53) and longer median length of stay (10.0 vs 5.3 days, P < .01). In conclusion, acute RRT in contemporary CICUs was associated with the provision of other advanced therapies and lower survival.Conclusions: These data underscore the risks associated with the provision of renal support in patients with primary cardiovascular problems and the need to develop standardized indications and potential futility measures in this specialized population. [ABSTRACT FROM AUTHOR]

Pulmonary hypertension (PH) frequently occurs in patients with left heart disease (LHD), including heart failure with reduced and preserved ejection fraction and valvular heart disease. PH in patients with LHD is associated with worse outcomes making it an attractive target of therapy. Despite the strong rational for treatment, no clear benefits from treating with pulmonary arterial hypertension specific therapies in patients with PH from LHD have been found in clinical trials and some studies have demonstrated harm. Therefore, PH in the setting of LHD should be managed with optimal medical and surgical treatment of LHD and identification and treatment of comorbidities that could contribute to PH. Additionally, significant PH is a contraindication to heart transplantation and, in select patients with left heart failure, left ventricular unloading with prolonged inotrope infusion or left ventricular assist device implantation may successfully reduce pulmonary artery pressures and facilitate transplantation. [ABSTRACT FROM AUTHOR]

Abstract: Inguinal hernia is associated with a multitude of genetic syndromes. Disorders of the microfibril, elastin, collagen, and the glycosaminoglycan component of the extracellular matrix can result in an increase in the likelihood of inguinal hernia. In addition, inguinal hernia may be the presenting feature of disorders of sexual differentiation. Inguinal hernia of unknown etiology also occurs more commonly in several other groups of genetic diseases including chromosomal disorders, microdeletion disorders such as 22q11.2 microdeletion, and in single gene disorders. We review the genetics of connective tissue formation and focus on a series of genetic conditions that may present with or are characterized by a higher risk of inguinal hernia. A comprehensive review of the literature aims to provide a diagnostic framework to aid in the identification of patients with inguinal hernia as part of underlying genetic disease. [Copyright &y& Elsevier]

Colobomata are etiologically heterogeneous and may occur as an isolated defect or as a feature of a variety of single-gene disorders, chromosomal syndromes, or malformation syndromes. Although not classically associated with Marfan syndrome, colobomata have been described in several reports of Marfan syndrome, typically involving the lens and rarely involving other ocular structures. While colobomata of the lens have been described in Marfan syndrome, there are very few reports of coloboma involving other ocular structures. We report a newborn boy presenting with coloboma of the iris, lens, retina, and optic disk who was subsequently diagnosed with Marfan syndrome. Marfan syndrome is a disorder of increased TGFβ signaling, and recent work in the mouse model suggests a role for TGFβ signaling in eye development and coloboma formation, suggesting a causal association between Marfan syndrome and coloboma. [Copyright &y& Elsevier]

The last decade has brought tremendous interest in the problem of cardiogenic shock. However, the mortality rate of this syndrome approaches 50%, and other than prompt myocardial revascularization, there have been no treatments proven to improve the survival of these patients. The bulk of studies have been in patients with acute myocardial infarction, and there is little evidence to guide the clinician in those patients with heart failure cardiogenic shock (HF-CS). An International Society for Heart and Lung Transplant consensus conference was organized to better define, diagnose, and manage HF-CS. There were 54 participants (advanced heart failure and interventional cardiologists, cardiothoracic surgeons, critical care cardiologists, intensivists, pharmacists, and allied health professionals) with vast clinical and published experience in CS, representing 42 centers worldwide. This consensus report summarizes the results of a premeeting survey answered by participants and the breakout sessions where predefined clinical issues were discussed to achieve consensus in the absence of robust data. Key issues discussed include systems for CS management, including the "hub-and-spoke" model vs a tier-based network, minimum levels of data to communicate when considering transfer, disciplines that should be involved in a "shock team," goals for mechanical circulatory support device selection, and optimal flow on such devices. Overall, the document provides expert consensus on some important issues facing practitioners managing HF-CS. It is hoped that this will clarify areas where consensus has been reached and stimulate future research and registries to provide insight regarding other crucial knowledge gaps. [ABSTRACT FROM AUTHOR]

In recent years, there have been significant advancements in the understanding, risk-stratification, and treatment of cardiogenic shock (CS). Despite improved pharmacologic and device-based therapies for CS, short-term mortality remains as high as 50%. Most recent efforts in research have focused on CS related to acute myocardial infarction, even though heart failure related CS (HF-CS) accounts for >50% of CS cases. There is a paucity of high-quality evidence to support standardized clinical practices in approach to HF-CS. In addition, there is an unmet need to identify disease-specific diagnostic and risk-stratification strategies upon admission, which might ultimately guide the choice of therapies, and thereby improve outcomes and optimize resource allocation. The heterogeneity in defining CS, patient phenotypes, treatment goals and therapies has resulted in difficulty comparing published reports and standardized treatment algorithms. An International Society for Heart and Lung Transplantation (ISHLT) consensus conference was organized to better define, diagnose, and manage HF-CS. There were 54 participants (advanced heart failure and interventional cardiologists, cardiothoracic surgeons, critical care cardiologists, intensivists, pharmacists, and allied health professionals), with vast clinical and published experience in CS, representing 42 centers worldwide. State-of-the-art HF-CS presentations occurred with subsequent breakout sessions planned in an attempt to reach consensus on various issues, including but not limited to models of CS care delivery, patient presentations in HF-CS, and strategies in HF-CS management. This consensus report summarizes the contemporary literature review on HF-CS presented in the first half of the conference (part 1), while the accompanying document (part 2) covers the breakout sessions where the previously agreed upon clinical issues were discussed with an aim to get to a consensus. [ABSTRACT FROM AUTHOR]

Abstract: Pontine tegmental cap dysplasia is a rare neurologic condition first described by Barth et al. in 2007. It is characterized by a vaulted pontine tegmentum projecting into the fourth ventricle and ventral pontine hypoplasia. Patients present with developmental delay, cerebellar and pyramidal abnormalities, cranial nerve dysfunction, and various extracranial malformations. The condition is thought to occur as a result of aberrant neuronal axonal guidance during embryologic development. Its genetic etiology has not been identified. We describe a further case of this rare condition with several features not previously reported, including aortic arch hypoplasia and mirror movements. [Copyright &y& Elsevier]

Epidemiological studies have identified nitrosamines as a risk factor for Type I (insulin dependent) diabetes mellitus. These compounds require bioactivation by cytochrome P450 2E1 (CYP2E1) for exertion of their toxic effects. Two mammalian insulin secreting pancreatic β-cell lines BRIN BD11h2E1 and INS-1h2E1, which express human full length CYP2E1 cDNA, were used to elucidate the role of CYP2E1-mediated nitrosamine bioactivation in pancreatic β-cell dysfunction and destruction. These cell lines were shown to metabolise dimethylnitrosamine to produce formaldehyde at rates of 3.41 ± 0.24 and 3.65 ± 0.26 nmol/min mg microsomal protein, respectively. Following incubation with various concentrations of the nitrosamines dimethylnitrosamine, N-nitrosopyrrolidine and 1-nitrospiperidine, all of which are bioactivated by CYP2E1, cytotoxicity and DNA damage were assessed using either the neutral red assay or comet assay respectively. Exposure of CYP2E1 expressing cells to nitrosamines resulted in significant dose-dependent decreases in cell viability, which were not seen in cells which did not express CYP2E1. Following culture with nitrosamine concentrations as low as 2.5 mM 1-nitrosopiperidine, cell viability was significantly lower in BRIN BD11h2E1 and INS-1h2E1 cell lines in comparison to the BRIN BD11 and INS-1 parental cell lines (72.5 ± 4.96 and 66.4 ± 3.09% in BRIN BD11h2E1 and INS-1h2E1 versus 109.0 ± 3.40 and 100.0 ± 3.25% in BRIN BD11 and INS-1 respectively, P < 0.001). The highest dose of any of the nitrosamines tested failed to significantly reduce cell viability in the cells which lacked CYP2E1. Expression of CYP2E1 did not cause any change in the basal level of DNA damage in any of the cell lines. However, 16 h exposure to various nitrosamines resulted in significant dose-dependent DNA damage in the BRIN BD11h2E1 and INS-1h2E1 cells compared to their respective non CYP2E1-expressing parental controls, e.g. DNA damage increased from 34.38 ± 1.25 to 44.01 ± 1.56% DNA in comet tail in BRIN BD11h2E1 cells incubated with 10 or 40 mM N-nitrosopyrrolidine, respectively (P < 0.001). Similar treatment of the BRIN BD11 and INS-1 cell lines did not result in a significant increase in DNA damage (20.33 ± 1.0 and 22.4 ± 0.98% DNA in comet tail). The pancreatic β-cell is richly vascularised and expresses CYP2E1. This study suggests that expression of human CYP2E1 in pancreatic β-cells make them highly susceptible to cytotoxicity and DNA damage by nitrosamines and other agents bioactivated by CYP2E1. [Copyright &y& Elsevier]

Proteins and enzymes for commercial use are often dried in order to extend their shelf lives. This study examined the effects of disaccharides (sucrose and trehalose), polymers (dextran and maltodextrin) and disaccharide–polymer mixtures on the stability of subtilisin, a common industrial laundry detergent enzyme, during drying and during subsequent storage in dried solids containing perborate, a laundry detergent additive that hydrolyzes to form hydrogen peroxide in the presence of water. Subtilisin is susceptible to oxidation by hydrogen peroxide at a partially buried methionine residue, which results in loss of catalytic activity. Two drying methods were compared: spray coating and lyophilization. During both drying methods, the presence of a disaccharide, which can hydrogen bond to subtilisin in the place of lost water, was necessary to inhibit dehydration-induced unfolding of subtilisin. Dehydration-induced unfolding was assessed by second-derivative IR spectroscopy. However, even in the samples in which the protein’s secondary structure was perturbed, the protein refolded to the native conformation and exhibited full activity upon rehydration. None of the additives protected Met222 from oxidation during storage of the initially dry protein formulations at 37 °C and 20 or 75% relative humidity under oxidizing conditions. In contrast, the two additional methionine residues in the enzyme, Met119 and Met175, which are deeply buried in the interior of the protein, remained unmodified during storage of the dried formulations and became oxidized only if the enzyme was completely unfolded in aqueous solution. [Copyright &y& Elsevier]

The COVID-19 pandemic has presented a major unanticipated stress on the workforce, organizational structure, systems of care, and critical resource supplies. To ensure provider safety, to maximize efficiency, and to optimize patient outcomes, health systems need to be agile. Critical care cardiologists may be uniquely positioned to treat the numerous respiratory and cardiovascular complications of the SARS-CoV-2 and support clinicians without critical care training who may be suddenly asked to care for critically ill patients. This review draws upon the experiences of colleagues from heavily impacted regions of the United States and Europe, as well as lessons learned from military mass casualty medicine. This review offers pragmatic suggestions on how to implement scalable models for critical care delivery, cultivate educational tools for team training, and embrace technologies (e.g., telemedicine) to enable effective collaboration despite social distancing imperatives. • Acute complications of COVID-19 can result in severe perturbations of the respiratory, cardiovascular, and immune systems. • Critical care cardiologists may be uniquely positioned to develop and disseminate novel solutions to meet patient and workforce demands. • Many opportunities exist to develop scalable models of critical care delivery and effective research collaboration. [ABSTRACT FROM AUTHOR]

Pulmonary hypertension (PH) is a disease characterized by an increase in the pulmonary vascular resistance that typically progresses to right heart failure and death. It is classified into five groups. Management depends on the group classification. Group four PH, chronic thromboembolic pulmonary hypertension (CTEPH) is thought to be a result of acute pulmonary emboli that cause fibrosis and scarring of the pulmonary arteries with consequent obstruction. The diagnosis of CTEPH is made by identifying perfusion abnormalities on ventilation/perfusion (V/Q) scan. Other studies required for the diagnostic evaluation include transthoracic echocardiogram, right heart catheterization, NT pro-B-type natriuretic peptide and thrombophilia evaluation. Several other tests needed to exclude other causes of pulmonary hypertension include high-resolution computed tomography (HRCT), connective tissue disease evaluation, thyroid function testing, human immunodeficiency virus testing, and liver ultrasonography to exclude portal hypertension. The treatment for CTEPH is surgical pulmonary endarterectomy (PEA). In patients who are not candidates or decline PEA, pulmonary balloon angioplasty may be useful, however, further studies are required. Several pulmonary artery hypertension medications have been studied in the management of inoperable CTEPH or persistent PH following PEA including bosentan (improves hemodynamics but not exercise capacity), macitentan (improves both hemodynamics and clinical parameters), and riociguat (improves both hemodynamics and exercise capacity). However, only riociguat is approved by the Food and Drug Administration for this indication. [ABSTRACT FROM AUTHOR]

Revertant somatic mosaicism (RM) has been reported in genetic diseases including skin disorders and bone marrow failure (BMF) syndromes. We present examples of RM of haematopoietic cells in the context of inherited BMF syndromes with dramatically different clinical outcomes. Diamond Blackfan Anaemia (DBA) is an inherited BMF disorder caused by mutations/deletions in ribosomal proteins. We have a 9 year old male who required regular transfusions until he became transfusion independent at age 4. We identified a 184kb deletion on chromosome 12 encompassing 11 genes including RPS26 (known DBA gene). Significantly, we observed multiple independent copy neutral loss of heterozygosity (CNLOH) events on chromosome 12, correcting the 184kb deletion in a subset of blood cells, but not in hair. We propose RM as a mechanism for correction of the germline deletion resulting in spontaneous remission in the patient. We also recently identified germline mutations in SAMD9L, in a family with thrombocytopaenia, macrocytosis and ALL. In this family, we see examples for somatic mosaicism leading to a severe blood phenotype as well as CNLOH RM causing milder phenotypes in different family members. RM needs to be considered when selecting tissue source for diagnosis in carriers with mild phenotype/remission, and use of patient-derived cell lines for drug screens with multiple rounds of cell replication. We are currently trying to understand and manipulate revertant clone selection and hope this will open windows for rational correction and selection protocols for effective therapeutic intervention. Experimental manipulations to select clones that improve clinical phenotype have substantive implications on efficiencies of gene manipulations, manufacture and quality control requirements of autologous cellular therapies. [ABSTRACT FROM AUTHOR]

The cardiac intensive care unit (CICU) has changed considerably over time and now serves a unique patient population with a high burden of cardiovascular and noncardiovascular critical illness. Patient complexity and technological evolutions in the CICU have catalyzed the development of critical care cardiology, a fledgling discipline that combines specialization in cardiovascular diseases with knowledge and experience in critical care medicine. Numerous uncertainties and challenges threaten to stymie the growth of this field. A multidisciplinary dialogue focused on the best care design for the CICU patient is needed as we consider alternative approaches to clinical training, staffing, and investigation in this rapidly evolving arena. [ABSTRACT FROM AUTHOR]

Abstract: Pontocerebellar hypoplasia exhibits a diverse range of etiologies, including six known autosomal recessive, single gene disorders. We describe a molecularly confirmed case of pontocerebellar hypoplasia type 4, a rare and severe neonatal phenotype with a novel TSEN54 mutation, presenting with polyhydramnios, hypertonia, and early neonatal death. The patient manifested severe hypoplasia of the cerebellum and brainstem. The neuropathologic findings in pontocerebellar hypoplasia type 4 develop late in gestation, and therefore prenatal diagnosis with ultrasonography is of limited use. Establishing a molecular diagnosis in the proband is critical for allowing couples to plan future pregnancies. [Copyright &y& Elsevier]

Oxidative DNA damage has been suggested to contribute to the decline in T cell clone (TCC) function with increased age in vitro. To test this hypothesis the effect of a reduced oxygen tension culture system (6% O2) on TCCs was examined. Specifically, the effects of the altered culture conditions on DNA damage levels, in vitro lifespan and proliferative capacity were assessed in five independently derived human CD4+ TCCs. DNA damage levels over the entire lifespan were significantly lowered by reducing oxygen tension. Lifespan (total population doublings (PDs) achieved) and proliferative capacity (PDs/week) were reduced for all clones under reduced oxygen tension when compared to standard culture conditions. This observed tendency warrants further investigation using a greater number of clones from donors of all age groups before definitive conclusions regarding the effect of low oxygen tension on the lifespan and proliferative capacity of TCC can be made. However, these results may suggest that the reduced oxygen tension culture system has interfered with some aspect of T cell biology not yet examined within the remit of this study. [Copyright &y& Elsevier]

DNA damage has been shown to increase with age in lymphocytes of healthy humans and in human CD4+ T cell clones. Such genetic damage, if unrepaired, may have a detrimental effect on lymphocyte-mediated immune responses. This study investigated DNA excision repair capacity of human CD4+ T cell clones as a function of age in vitro.Cultures of T cell clones were treated with a range of DNA damaging agents; hydrogen peroxide, N-methyl-N′-nitro-N-nitrosoguanidine or 254 nm ultraviolet irradiation. Following treatment, the amount of DNA damage in the clones was determined over a time course using modified comet assays. The results obtained revealed a decline related to in vitro age in the DNA repair capacity of clones derived from a 26 and a 45 year old donor. This decline may represent at least a partial explanation for the age related increase in DNA damage in these clones when cultured in vitro. In contrast, there was no evidence for a decline related to in vitro age in repair capacity in the clones derived from an 80 year old SENIEUR donor. An alternative mechanism must underlie the age related increased in DNA damage in these clones when cultured in vitro. [Copyright &y& Elsevier]

The role of CYP2E1 in ketone-stimulated insulin release was investigated using isolated pancreatic islets of Langerhans and two mammalian insulin secreting pancreatic β-cell lines engineered to stably express human CYP2E1 (designated BRIN BD11h2E1 and INS-1h2E1). Isolated rat pancreatic islets were shown to express the CYP2E1 isoform which was inducible by pretreatment of animals with acetone. The cDNA encoded CYP2E1 was expressed and inducible in the engineered cells as shown by Western blotting. The transfected protein was enzymatically active in the heterologous cells as determined by p-nitrophenol hydroxylation rates (0.176±0.08 vs. 0.341±0.08 nmol/min/mg microsomal protein in BRIN BD11 control cells and BRIN BD11h2E1 cells respectively, P<0.001; 0.204±0.03 vs. 0.633±0.102 nmol/min/mg microsomal protein in INS-1 and INS-1h2E1, respectively, P<0.001). Cultivation of CYP2E1 expressing BRIN BD11h2E1 and INS-1h2E1 cells in 40 mM ethanol increased the rate of p-nitrophenol hydroxylation (0.968±0.09 nmol/min/mg microsomal protein, P<0.001 and 0.846±0.103 nmol/min/mg microsomal protein, P<0.001, respectively) providing further evidence that the heterologous protein is inducible. Cultivation of control cells with ethanol had no observable effect (0.186±0.05 and 0.195±0.03 in BRIN BD11 and INS-1, respectively). These cell lines also express NADPH-cytochrome P450 reductase protein which was enzymatically active (0.632±0.023 in parental BRIN BD11 vs. 0.657±0.066 without ethanol and 0.824±0.014 nmol/min/mg microsomal protein with ethanol in BRIN BD11h2E1, P<0.05; and 1.568±0.118 in parental INS-1 vs. 1.607±0.093 without ethanol and 1.805±0.066 nmol/min/mg microsomal protein with ethanol in INS-1h2E1, P<0.05) thereby providing a functional cytochrome P450 system. The insulin secretory response of control cell lines and islets was similar to cell lines and islets which had been chemically pretreated, to induce CYP2E1 expression, in response to known nutrient secretagogues. However, insulin output was significantly higher in pretreated islets (1.3-fold, P<0.05) and CYP2E1 expressing cell lines (BRIN BD11h2E1 2.3-fold, P<0.001; INS1-1h2E1 1.6-fold, P<0.001) when stimulated with the ketone 3-hydroxybutyrate than control islets and parental cell lines respectively. Similar acute exposure to acetoacetate enhanced insulin secretion by 1.3-fold (P<0.05) in pretreated islets, 2.6-fold (P<0.001) in ethanol pretreated BRIN BD11h2E1 and 1.4-fold (P<0.001) in ethanol pretreated INS-1h2E1 cells compared to the respective control islets or ethanol pretreated control parental cells. Therefore, these studies highlight a possible role for CYP2E1 in pancreatic cell dysfunction. [Copyright &y& Elsevier]

The results of previous work from our laboratories have suggested that free radical damage to T cells as they age may contribute to the age-related decline in the T cell-mediated immune response. The aims of this investigation were to assess the efficiency of in vivo antioxidant capacity through determining the antioxidant capacity of plasma using the ferric reducing ability of plasma assay, and to assess the levels and types of DNA damage (as a measure of in vivo antioxidant efficiency) using the alkaline comet assay and two enzymatic modifications of the comet assay, in peripheral blood mononuclear cells (PBMCs) from nonagenarian subjects drawn from the Swedish NONA Immune Study. The results obtained were compared with those from middle-aged (40–60 years) controls to identify potential anti-immunosenescent effects of in vivo antioxidants. The results revealed a significantly higher plasma antioxidant capacity in NONA subjects compared to controls, and these results support a relationship between longevity and intact immune function, which may be underpinned by antioxidant defences which reduce free radical damage to PBMC, thus helping to maintain cell function. The NONA subjects were found to have similar levels of DNA damage in their PBMCs to those found in middle aged controls. [Copyright &y& Elsevier]

An age-related increase of DNA damage/mutation has been previously reported in human lymphocytes. The high copy number and mutation rate make the mtDNA genome an ideal candidate for assessing damage and to act as a potential biomarker of ageing. In the present study, two assays were developed to evaluate the level of mtDNA4977 and the accumulation of point mutations with age. A competitive polymerase chain reaction (PCR) methodology incorporating three primers was used to detect and quantify the levels of mtDNA4977 and a novel heteroduplex reference strand conformational analysis (RSCA) technique was used to analyse the accumulation of point mutations. The assays were applied to an in vitro model of T cell ageing and ex vivo DNA samples from an elderly cohort of subjects and a younger control group. The mtDNA4977 was detected in all the DNA samples examined but only a very low concentration was observed and no age-related increase or accumulation was observed. No accumulation of point mutations was identified using RSCA within the T cell clones as they were aged or the ex vivo lymphocytes from the elderly cohort. A higher level of variation was observed within the ex vivo DNA samples, verifying the high resolution of RSCA and its ability to identify different mtDNA species, although no correlation with age was observed. The low level of mtDNA damage observed with respect to the ex vivo lymphocyte DNA samples within this study may be due in part to the high turnover of blood cells/mtDNA, which may inhibit the accumulation of genetically abnormal mtDNA that may play a role in immunosenescence. A similar explanation may also apply to the in vitro model of T cell ageing if the vast majority of the cells are replicating rather than entering senescence. [Copyright &y& Elsevier]

Background Cerebellar vermis hypoplasia has been associated with a large number of chromosomal abnormalities and metabolic disorders, with few candidate genes clearly linked to isolated cerebellar vermis hypoplasia. Patient Description We describe on a 12-year-old boy with inferior vermian hypoplasia associated with a novel de novo microdeletion. He presented with intellectual, speech and language impairment, unilateral facial nerve weakness, marked constipation, and bilateral hand and foot anomalies that were not consistent with any previously described syndrome. His hand features were digital reductions similar to those seen in 4q34 deletion syndrome, known as the “tale of the nail” sign. Cranial magnetic resonance imaging demonstrated isolated inferior cerebellar vermis hypoplasia. Results A de novo 1.4 Mb interstitial deletion was identified at 8q13.1-q13.2 on chromosomal microarray. This copy number variant involves 18 human genome reference sequence genes, with 11 Mendelian Inheritance in Man genes. Homozygous mutations in one of these genes ( CSPP1 ) has recently been recently described as causing Joubert syndrome. Conclusion We propose that the constellation of clinical features in this child represents a novel microdeletion syndrome and hypothesize that CSPP1 or other genes within the deleted region contribute to the cerebellar development. [ABSTRACT FROM AUTHOR]