Secret History: Return of the Black Death Channel 4, 7-8pm In 1348 the Black Death swept through London, killing people within days of the appearance of their first symptoms. Exactly how many died, and why, has long been a mystery. This Secret History documentary follows experts as they pick through the evidence and reveal why the plague killed on such a scale. And they ask, what might be coming next?

Medscape

Assay for lipid peroxides in animal tissues by thiobarbituric acid reaction

admission. This proportion could already be greater in some parts of the country and may increase if referrals of cases of self-poisoning increase faster than the facilities for their assessment and management. The provision of social work and psychiatric expertise in casualty departments may be one means of preventing unnecessary medical admissions without risk to the patients. Dr Blake's and Dr Bramble's figures do not demonstrate, however, that any advantage would attach to medical teams taking over assessment from psychiatrists except that, by implication, assessments would be completed sooner by staff working on the ward full time. What the figures actually suggest is that if assessment of overdoses were left to house doctors there would be an increase in admissions to psychiatric units (by 19°U), outpatients (by 5O°'), and referrals to social services (by 140o). So for house doctors to assess overdoses would provide no economy for the psychiatric or social services. The study does not tell us what the consequences would have been for the six patients who the psychiatrists would have admitted but to whom the house doctors would have offered outpatient appointments. E J SALTER

Vitamin D deficiency.

There has been much effort recently to define the role of adipocytokines, which are soluble mediators derived mainly from adipocytes (fat cells), in the interaction between adipose tissue, inflammation and immunity. The adipocytokines adiponectin and leptin have emerged as the most abundant adipocyte products, thereby redefining adipose tissue as a key component not only of the endocrine system, but also of the immune system. Indeed, as we discuss here, several adipocytokines have a central role in the regulation of insulin resistance, as well as many aspects of inflammation and immunity. Other adipocytokines, such as visfatin, have only recently been identified. Understanding this rapidly growing family of mainly adipocyte-derived mediators might be of importance in the development of new therapies for obesity-associated diseases.

Adipocytokines: mediators linking adipose tissue, inflammation and immunity.

The cardiovascular and other actions of angiotensin II (Ang II) are mediated by AT(1) and AT(2) receptors, which are seven transmembrane glycoproteins with 30% sequence similarity. Most species express a single autosomal AT(1) gene, but two related AT(1A) and AT(1B) receptor genes are expressed in rodents. AT(1) receptors are predominantly coupled to G(q/11), and signal through phospholipases A, C, D, inositol phosphates, calcium channels, and a variety of serine/threonine and tyrosine kinases. Many AT(1)-induced growth responses are mediated by transactivation of growth factor receptors. The receptor binding sites for agonist and nonpeptide antagonist ligands have been defined. The latter compounds are as effective as angiotensin converting enzyme inhibitors in cardiovascular diseases but are better tolerated. The AT(2) receptor is expressed at high density during fetal development. It is much less abundant in adult tissues and is up-regulated in pathological conditions. Its signaling pathways include serine and tyrosine phosphatases, phospholipase A(2), nitric oxide, and cyclic guanosine monophosphate. The AT(2) receptor counteracts several of the growth responses initiated by the AT(1) and growth factor receptors. The AT(4) receptor specifically binds Ang IV (Ang 3-8), and is located in brain and kidney. Its signaling mechanisms are unknown, but it influences local blood flow and is associated with cognitive processes and sensory and motor functions. Although AT(1) receptors mediate most of the known actions of Ang II, the AT(2) receptor contributes to the regulation of blood pressure and renal function. The development of specific nonpeptide receptor antagonists has led to major advances in the physiology, pharmacology, and therapy of the renin-angiotensin system.

https://pharmrev.aspetjournals.org/content/pharmrev/52/3/415.full.pdf

International Union of Pharmacology. XXIII. The Angiotensin II Receptors

Angiotensin II is known primarily for its effects on blood pressure and electrolyte homeostasis, but recent studies suggest that angiotensin II may play a role in the regulation of cellular growth. This study was undertaken to identify the angiotensin II receptor subtypes expressed during fetal and neonatal development and to characterize their cellular localization. Using an in situ receptor binding assay on sagittal frozen sections of fetal and neonatal rats, bound 125I-[Sar1,Ile8]-angiotensin II was visualized by film and emulsion autoradiography. Bound radioligand was detected by E11 (embryonic day 11) and maximal binding occurred by E19-21. Radioligand binding remained unaltered 30 min after birth, whereas a noticeable and stable decrease was observed 12 h postparturition. The highly abundant angiotensin II receptors were shown to be AT2 by the marked reduction in radioligand binding achieved with PD123177 (10(-7)M), a specific AT2 receptor antagonist, whereas DuP 753 (10(-5)M), an AT1 receptor antagonist, had little effect. Emulsion autoradiography showed radioligand binding in the undifferentiated mesenchyme of the submucosal layers of the intestine and stomach, connective tissue and choroid surrounding the retina, subdermal mesenchyme adjacent to developing cartilage, diaphragm, and tongue. Residual AT2 receptors were found on the dorsal subdermal region of the tongue 72 h after birth. AT1 receptors were detected in the placenta at E13 and in the aorta, kidney, lung, liver, and adrenal gland at E19-21, consistent with an adult distribution. The transient expression of AT2 receptors in the mesenchyme of the fetus suggests a role of angiotensin II in fetal development.

Expression of AT2 receptors in the developing rat fetus.

Background Experimental and human studies demonstrate that long-term exposure to elevated aldosterone levels results in cardiac and vascular damage. Methods We investigated long-term cardiovascular outcomes in patients with primary aldosteronism after surgical or medical treatment. Fifty-four patients with or without evidence of adrenal adenomas were prospectively followed up for a mean of 7.4 years after treatment with adrenalectomy or spironolactone. Patients with primary aldosteronism were compared with patients with essential hypertension and were treated to reach a blood pressure of less than 140/90 mm Hg. The main outcome measure was a combined cardiovascular end point comprising myocardial infarction, stroke, any type of revascularization procedure, and sustained arrhythmias. Results At baseline, the prevalence of cardiovascular events was greater in primary aldosteronism (35%) than in essential hypertension (11%) (odds ratio, 4.61; 95% confidence interval, 2.38-8.95; P P  = .85). Cox analysis indicated that older age and longer duration of hypertension were factors independently associated with the cardiovascular end point. Cardiovascular outcome was comparable in patients with aldosteronism treated with adrenalectomy vs aldosterone antagonists ( P  = .71). Conclusion Primary aldosteronism is associated with a cardiovascular complication rate out of proportion to blood pressure levels that benefits substantially from surgical and medical treatment in the long term.

https://jamanetwork.com/journals/jamainternalmedicine/articlepdf/413688/ioi70177_80_85.pdf

Cardiovascular outcomes in patients with primary aldosteronism after treatment.

ContextExperimental animal studies indicate that exposure to increased aldosterone levels might result in renal damage, but the clinical evidence supporting this role of aldosterone is preliminary.ObjectiveTo determine the long-term outcome of renal function in patients with primary aldosteronism after surgical or medical treatment.Design, Setting, and ParticipantsProspective study conducted at an Italian university medical center among a consecutive sample of 50 patients who were diagnosed as having primary aldosteronism between January 1994 and December 2001 and who were followed up for a mean of 6.4 years after treatment with adrenalectomy or spironolactone. Patients with primary aldosteronism were compared with 100 patients with essential hypertension, matched for severity and duration of hypertension. All patients were treated with antihypertensive drugs to reach a target blood pressure of less than 140/90 mm Hg.Main Outcome MeasuresPrimary outcome measures were rates of change of glomerular filtration rate and albuminuria during follow-up. Detection of new-onset microalbuminuria and restoration of normal albumin excretion during follow-up were considered as secondary outcomes.ResultsAt baseline, glomerular filtration rate and albuminuria were higher in patients with primary aldosteronism than those with essential hypertension. The mean blood pressure during the study was 136/81 mm Hg in the primary aldosteronism group and 137/81 mm Hg in the essential hypertension group. Glomerular filtration rate and albuminuria declined during the initial 6-month period in both groups, with a change that was significantly greater (P<.001 for both variables) in patients with primary aldosteronism. Subsequent rate of decline of glomerular filtration was comparable in the 2 groups, whereas albuminuria did not progress in the remainder of the follow-up. Restoration of normal albumin excretion from microalbuminuria was significantly more frequent in primary aldosteronism than in essential hypertension (P = .02).ConclusionIn the majority of patients in this study, primary aldosteronism was characterized by partially reversible renal dysfunction in which elevated albuminuria is a marker of a dynamic rather than structural renal defect.

https://jamanetwork.com/journals/jama/articlepdf/202998/JOC60066.pdf

Long-term Renal Outcomes in Patients With Primary Aldosteronism

Exposure to excess aldosterone results in cardiac damage in hypertensive states. We evaluated the long-term cardiac structural and functional evolution in patients with primary aldosteronism after surgical or medical treatment. Fifty-four patients with primary aldosteronism were enrolled in a prospective study and were followed for a mean of 6.4 years after treatment with adrenalectomy (n=24) or spironolactone (n=30). At baseline, echocardiographic measurements of patients with primary aldosteronism were compared with those of 274 patients with essential hypertension. Patients with primary aldosteronism had greater left ventricular mass, more prevalent left ventricular hypertrophy, lower early:late-wave diastolic filling velocities ratio, and longer deceleration time than patients with essential hypertension but no differences in relative wall thickness and systolic function. During follow-up, average blood pressure was 135/82 and 137/82 mm Hg in patients treated with adrenalectomy and spironolactone, respectively. In the initial 1-year period, left ventricular mass decreased significantly only in adrenalectomized patients. Subsequent changes in left ventricular mass were greater in patients treated with spironolactone, with an overall change from baseline to the end of follow-up that was comparable in the 2 groups. Prevalence of hypertrophy decreased in both treatment groups, whereas diastolic parameters had only mild and nonsignificant improvement. Changes in blood pressure and pretreatment plasma aldosterone were independent predictors of left ventricular mass decrease in both treatment groups. Thus, in the long-term, both adrenalectomy and spironolactone are effective in reducing left ventricular mass in patients with primary aldosteronism, with effects that are partially independent of blood pressure changes.

Long-Term Cardiac Effects of Adrenalectomy or Mineralocorticoid Antagonists in Patients With Primary Aldosteronism

Objectives: Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver-related morbidity and is frequently associated with obesity and metabolic syndrome. The recently discovered hormone adiponectin is produced by adipose tissue, and low plasma adiponectin is considered a key factor in the development of the insulin resistance underlying metabolic syndrome. Animal studies suggest that adiponectin may protect against non-alcoholic steatohepatitis, but direct evidence in humans is lacking. We therefore conducted this study to assess the relationship between plasma adiponectin and nonalcoholic fatty liver disease to explore its role in the pathogenesis of this disease. Design and methods: We measured plasma adiponectin and anthropometric, biochemical, hormonal and metabolic correlates in a group of 17 NAFLD patients with diagnosis confirmed by biopsy, and 20 controls with comparable age, body-mass index and sex. Furthermore we compared plasma adiponectin in patients with simple steatosis and steatohepatitis. Results: Plasma adiponectin was significantly lower in NAFLD patients than controls (5.93^0.45 vs 15.67^1.60 ng/ml). Moreover, NAFLD patients were significantly more insulin resistant while having similar serum leptin. Adiponectin was similar in simple steatosis and in steatohepatitis (6.16^0.78 vs 5.69^0.49 ng/ml). An inverse correlation was observed between adiponectin and homeostatic model assessment (HOMA) of insulin resistance (P ¼ 0.008), while adiponectin did not correlate with serum transaminases and lipid values. Conclusions: These data support a role for low circulating adiponectin in the pathogenesis of NAFLD and confirm the strict association between reduced adiponectin production by adipose tissue, NAFLD and insulin resistance.

/pdf/plasma-adiponectin-is-decreased-in-nonalcoholic-fatty-liver-28xskiu0xp.pdf

Leonardo A. Sechi

Papers

Expression of AT2 receptors in the developing rat fetus.

Cardiovascular outcomes in patients with primary aldosteronism after treatment.

Long-term Renal Outcomes in Patients With Primary Aldosteronism

Long-Term Cardiac Effects of Adrenalectomy or Mineralocorticoid Antagonists in Patients With Primary Aldosteronism

Plasma adiponectin is decreased in nonalcoholic fatty liver disease.