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Understanding the Role of Androgen Action in Female Adipose Tissue.
No full textAdipose tissue is an important target of androgen action in humans. Androgens exert important effects on adipose tissue biology, including fat mass expansion and distribution, insulin signalling and lipid metabolism. In conditions of female androgen excess such as polycystic ovary syndrome (PCOS), androgens exert metabolically deleterious effects on adipose tissue function in a depot-specific manner. Androgen excess in women is metabolically deleterious, and adverse metabolic effects may be mediated by effects on preadipocyte differentiation and adipocyte hypertrophy. Circulating androgen burden correlates with adiposity in women, and drives visceral fat mass accumulation. Adipose tissue is also an important organ of pre-receptor androgen metabolism, and is host to a complex network of androgen activating and inactivating enzymes. Adipose androgen generation is increased in subcutaneous (SC) adipose tissue in women with PCOS, and intra-adipose concentrations of potent androgens may exceed those measured in peripheral circulation. Increased expression of the key androgen-activating enzyme aldo-ketoreductase type 1C3 in PCOS SC adipose tissue leads to high concentrations of testosterone and dihydrotestosterone. Enhanced local androgen generation may further contribute to the adverse metabolic profile of women with PCOS by exerting lipotoxic effects on local adipose biology
Systematic Review: Clinical Metabolomics to Forecast Outcomes in Liver Transplantation Surgery.
No full textLiver transplantation is an effective intervention for end-stage liver disease, fulminant hepatic failure, and early hepatocellular carcinoma. Yet, there is marked patient-to-patient variation in liver transplantation outcomes. This calls for novel diagnostics to enable rational deployment of donor livers. Metabolomics is a postgenomic high-throughput systems biology approach to diagnostic innovation in clinical medicine. We report here an original systematic review of the metabolomic studies that have identified putative biomarkers in the context of liver transplantation. Eighteen studies met the inclusion criteria that involved sampling of blood ( = 4), dialysate fluid ( = 4), bile ( = 5), and liver tissue ( = 5). Metabolites of amino acid and nitrogen metabolism, anaerobic glycolysis, lipid breakdown products, and bile acid metabolism were significantly different in transplanted livers with and without graft dysfunction. However, criteria for defining the graft dysfunction varied across studies. This systematic review demonstrates that metabolomics can be deployed in identification of metabolic indicators of graft dysfunction with a view to implicated molecular mechanisms. We conclude the article with a horizon scanning of metabolomics technology in liver transplantation and its future prospects and challenges in research and clinical practice
MANAGEMENT OF ENDOCRINE DISEASE: Visual Morbidity in Patients with Pituitary Adenoma.
No full textVisual dysfunction is an important element in the morbidity encountered in patients with pituitary adenoma leading to functional impairment and compromised quality of life. It consists of many parameters (even in the absence of reported symptomatology) as a result of tumour growth in proximity to structures critical for vision (anterior visual pathway, cranial nerves within cavernous sinuses), and as an adverse consequence of therapeutic interventions. Adenoma resection leads to high rates of visual improvement and possibly continues beyond a year post-surgery but the exact timing of maximum effect requires elucidation. Retinal nerve fibre layer measurement may be a reliable, objective parameter predicting favourable visual outcomes, although its prognostic value when pathological, needs to be confirmed. For compromised vision after pituitary apoplexy, early surgical decompression remains usual practice until evidence-based guidance becomes available. The risk of radiation-induced visual toxicity is mainly influenced by total and per fraction dose of radiation and treatment modality. Careful selection of cases and of radiotherapy technique/planning are of major importance in minimising this risk. Dopamine agonists lead to visual recovery in a considerable number of prolactinoma patients. Visual morbidity should be considered a vital indicator in the metrics of quality of service/care in pituitary disease making regular, full ophthalmic examination an essential component of modern management of pituitary pathology at all time points of patient pathway. Well-designed studies minimising effects of bias and using tools and scoring systems reliably reflecting visual status will provide robust evidence on valid prognostication and patient stratification guiding clinical decision making
The feasibility, safety and optimization of multiple prolonged breath-holds for radiotherapy.
No full textBACKGROUND & PURPOSE
Multiple, short breath-holds are now used in single radiotherapy treatment sessions. Here we investigated the feasibility and safety of multiple prolonged breath-holds in a single session. We measured how long is a second breath-hold if we prematurely terminate a single, prolonged breath-hold of >5 min either by using a single breath of oxygen (O), or by reintroducing preoxygenation and hypocapnia. We also investigated the feasibility and safety of undertaking 9 prolonged breath-holds in a row.
MATERIALS & METHODS
30 healthy volunteers with no previous breath-holding experience were trained to perform single prolonged breath-holds safely.
RESULTS
Their mean single, prolonged breath-hold duration was 6.1 ± 0.3 se minutes (n = 30). In 18/18 subjects, premature termination (at 5.1 ± 0.2 min) with a single breath of 60% O, enabled a 2nd safe breath-hold lasting 3.3 ± 0.2 min. In 18/18 subjects, premature termination at 5.3 ± 0.2 min) by reintroducing preoxygenation and hypocapnia, enabled a 2nd safe breath-hold lasting 5.8 ± 0.3 min. 17/17 subjects could safely perform 9 successive prolonged breath-holds, each terminated (at 4.3 ± 0.2 min) by reintroducing preoxygenation and hypocapnia for 3.1 ± 0.2 min. The 9th unconstrained breath-hold (mean of 6.0 ± 0.3 min) lasted as long as their single breath-hold.
CONCLUSIONS
Multiple prolonged breath-holds are possible and safe. In a ∼19 min treatment session, it would therefore be possible to have ∼13 min for radiotherapy treatment (3 breath-holds) and ∼6 min for setup and recovery. In a 65 min session, it would be possible to have 41 min for radiotherapy and 25 min for setup and recovery
Hepatitis C Virus Epidemiology and the Impact of Interferon-Free Hepatitis C Virus Therapy.
No full textThe public health impact of hepatitis C virus (HCV) infection has been realized only recently. Globally, 71 million people are living with HCV chronic infection. HCV prevalence is higher in some regions and countries, as well as in some subpopulations such as people who inject drugs, prisoners, or people living with HIV. In 2017, an estimated 580,000 people died from HCV, largely because of long-term complications of the disease. The advent of direct-acting antivirals (DAAs), which are highly effective in treating the infection and are well tolerated, led the World Health Organization (WHO) in 2016 to call for the elimination of HCV by 2030, which would be possible by meeting the numerical targets laid down by the organization. However, at present, only 12 countries are on track. Overall, only 20% of people with HCV have been diagnosed and only 7% of people diagnosed have initiated treatment, with major differences among countries. Underdiagnoses, a general lack of awareness, poor surveillance, and the prices of diagnostics and treatment remain major barriers to achieving the elimination goals. Comprehensive strategies, which include innovative models of care and the removal of reimbursement restrictions for treatment, are needed to overcome these public health and health system obstacles
A collaborative, individual-level analysis compared longitudinal outcomes across the International Network of Chronic Kidney Disease (iNETCKD) cohorts.
No full textRates of chronic kidney disease (CKD) progression, end stage kidney disease (ESKD), all-cause mortality, and cardiovascular (CVD) events among individuals with CKD vary widely across countries. Well-characterized demographic, comorbidity, and laboratory markers captured for prospective cohorts may explain, in part, such differences. To investigate whether core characteristics of individuals with CKD explain differences in rates of outcomes, we conducted an individual-level analysis of eight studies that are part of iNET-CKD, an international network of CKD cohort studies. Overall, the rate of CKD progression was 40 events/1000 person-year (95% confidence interval 39 - 41), 28 (27 - 29) for ESKD, 41 (40 - 42) for death, and 29 (28 - 30) for CVD events. However, standardized rates were highly heterogeneous across studies (over 92.5%). Interactions by study group on the association between baseline characteristics and outcomes were then identified. For example, the adjusted hazard ratio for CKD progression was 0.44 (95% confidence interval 0.35 - 0.56) for women vs. men among the Japanese (CKD-JAC), while it was 0.66 (0.59 - 0.75) among the Uruguayan (NRHP). The adjusted hazard ratio for ESKD was 2.02 (95% CI 1.88 - 2.17) per 10 units lower baseline eGFR among Americans (CRIC), while it was 3.01 (2.57 - 3.53) among Canadians (CanPREDDICT) (significant interaction for comparisons across all studies). The risks of CKD progression, ESKD, death, and CVD vary across countries even after accounting for the distributions of age, sex, comorbidities, and laboratory markers. Thus, our findings support the need for a better understanding of specific factors in different populations that explain this variation
Outcomes Following an Index Emergency Admission With Cholecystitis: A National Cohort Study.
No full textOBJECTIVE
The objective of this study was to evaluate the differences between patients who undergo cholecystectomy following index admission for cholecystitis, and those who are managed nonoperatively.
SUMMARY BACKGROUND DATA
Index emergency cholecystectomy following acute cholecystitis is widely recommended by national guidelines, but its effect on clinical outcomes remains uncertain.
METHODS
Data collected routinely from the Hospital Episode Statistics database (all admissions to National Health Service organizations in England and Wales) were extracted between April 1, 2002 and March 31, 2015. Analyses were limited to patients aged over 18 years with a primary diagnosis of cholecystitis. Exclusions included records with missing or invalid datasets, patients who had previously undergone a cholecystectomy, patients who had died without a cholecystectomy, and those undergoing cholecystectomy for malignancy, pancreatitis, or choledocholithiasis. Patients were grouped as either "no cholecystectomy" where they had never undergone a cholecystectomy following discharge, or "cholecystectomy." The latter group was then subdivided as "emergency cholecystectomy" when cholecystectomy was performed during their index emergency admission, or "interval cholecystectomy" when a cholecystectomy was performed within 12 months following a subsequent (emergency or elective) admission. Propensity Score Matching was used to match emergency and interval cholecystectomy groups. Main outcome measures included 1) One-year total length of hospital stay due to biliary causes following an index emergency admission with cholecystitis. 2) One-year mortality; defined as death occurring within 1 year following the index emergency admission with acute cholecystitis.
RESULTS
Of the 99,139 patients admitted as an emergency with acute cholecystitis, 51.1% (47,626) did not undergo a cholecystectomy within 1 year of index admission. These patients were older, with more comorbidities (Charlson Comorbidity Score ≥ 5 in 23.5% vs. 8.1%, P < 0.001) when compared to patients who did have a cholecystectomy. While all-cause 1-year mortality was higher in the nonoperated versus the operated group (12.2% vs. 2.0%, P < 0.001), gallbladder-related deaths were significantly lower than all other causes of death in the non-operated group (3.3% vs. 8.9%, P < 0.001). Following matching, 1-year total hospital admission time was significantly higher following emergency compared with interval cholecystectomy (17.7 d vs. 13 d, P < 0.001).
CONCLUSIONS
Over 50% of patients in England did not undergo cholecystectomy following index admission for acute cholecystitis. Mortality was higher in the nonoperated group, which was mostly due to non-gallbladder pathologies but total hospital admission time for biliary causes was lower over 12 months. Increasing the numbers of emergency cholecystectomy may risk over-treating patients with acute cholecystitis and increasing their time spent admitted to hospital
Alternative pathway androgen biosynthesis and human fetal female virilization.
No full textAndrogen biosynthesis in the human fetus proceeds through the adrenal sex steroid precursor dehydroepiandrosterone, which is converted to testosterone in the gonads, followed by further activation to 5α-dihydrotestosterone in genital skin, thereby facilitating male external genital differentiation. Congenital adrenal hyperplasia due to P450 oxidoreductase deficiency results in disrupted dehydroepiandrosterone biosynthesis, explaining undervirilization in affected boys. However, many affected girls are born virilized, despite low circulating androgens. We hypothesized that this is due to a prenatally active, alternative androgen biosynthesis pathway from 17α-hydroxyprogesterone to 5α-dihydrotestosterone, which bypasses dehydroepiandrosterone and testosterone, with increased activity in congenital adrenal hyperplasia variants associated with 17α-hydroxyprogesterone accumulation. Here we employ explant cultures of human fetal organs (adrenals, gonads, genital skin) from the major period of sexual differentiation and show that alternative pathway androgen biosynthesis is active in the fetus, as assessed by liquid chromatography-tandem mass spectrometry. We found androgen receptor expression in male and female genital skin using immunohistochemistry and demonstrated that both 5α-dihydrotestosterone and adrenal explant culture supernatant induce nuclear translocation of the androgen receptor in female genital skin primary cultures. Analyzing urinary steroid excretion by gas chromatography-mass spectrometry, we show that neonates with P450 oxidoreductase deficiency produce androgens through the alternative androgen pathway during the first weeks of life. We provide quantitative in vitro evidence that the corresponding P450 oxidoreductase mutations predominantly support alternative pathway androgen biosynthesis. These results indicate a key role of alternative pathway androgen biosynthesis in the prenatal virilization of girls affected by congenital adrenal hyperplasia due to P450 oxidoreductase deficiency
Abdominal Aortic Aneurysm Repair in Renal and Liver Transplant Recipients.
No full textBACKGROUND
Abdominal aortic aneurysm (AAA) repair in patients with organ transplant remains a challenge. We looked at AAA repair in patients with organ transplants at our tertiary liver and kidney transplant unit.
METHODS
A retrospective analysis of a prospectively maintained database was undertaken from January 2008 to July 2018. We looked at patient demographics, type of repair, and technical success including reinterventions, perioperative transplant organ function, and 30-day and 1-year survival rate. Eight of 662 patients who underwent AAA repair had a solid organ transplant. Of these, 5 were kidney transplants, 2 liver transplants, and 1 had kidney and liver transplant; 75% were male; and average age was 63.4 (range: 49-83). All patients had asymptomatic AAAs, and 6 were treated with standard endovascular repair, 1 standard repair with iliac branch device, and 1 open repair. Adjunctive techniques such as CO angiograms, deployment of main body through contralateral iliac, low-profile sheaths, custom-made stent grafts, and temporary axillo-femoral shunting were used to protect transplant organs. Thirty-day survival was 100% with 1 death at 5 months from liver failure, and 1 patient has a persistent type-2 endoleak 3 years after the procedure.
CONCLUSION
Abdominal aortic aneurysm repair in patients with organ transplants can be undertaken using adjunctive endovascular and open surgical techniques