The 11th edition of Harrison's Principles of Internal Medicine welcomes Anthony Fauci to its editorial staff, in addition to more than 85 new contributors. While the organization of the book is similar to previous editions, major emphasis has been placed on disorders that affect multiple organ systems. Important advances in genetics, immunology, and oncology are emphasized. Many chapters of the book have been rewritten and describe major advances in internal medicine. Subjects that received only a paragraph or two of attention in previous editions are now covered in entire chapters. Among the chapters that have been extensively revised are the chapters on infections in the compromised host, on skin rashes in infections, on many of the viral infections, including cytomegalovirus and Epstein-Barr virus, on sexually transmitted diseases, on diabetes mellitus, on disorders of bone and mineral metabolism, and on lymphadenopathy and splenomegaly. The major revisions in these chapters and many

Harrison's Principles of Internal Medicine

An overview of the self-organizing map algorithm, on which the papers in this issue are based, is presented in this article.

The Self-Organizing Map

In this paper we develop new Newton and conjugate gradient algorithms on the Grassmann and Stiefel manifolds. These manifolds represent the constraints that arise in such areas as the symmetric eigenvalue problem, nonlinear eigenvalue problems, electronic structures computations, and signal processing. In addition to the new algorithms, we show how the geometrical framework gives penetrating new insights allowing us to create, understand, and compare algorithms. The theory proposed here provides a taxonomy for numerical linear algebra algorithms that provide a top level mathematical view of previously unrelated algorithms. It is our hope that developers of new algorithms and perturbation theories will benefit from the theory, methods, and examples in this paper.

http://www-math.mit.edu/~edelman/publications/geometry_of_algorithms.pdf

The Geometry of Algorithms with Orthogonality Constraints

结节病易误诊,据王洪武等~([1])收集国内18篇关于此病误诊的文献,误诊率高达63.2%,当然有误诊就会有误治,如孙永昌等~([2])报道26例结节病在影像学检查诊断的第一印象中拟诊结核5例,其中就有2例完成规范的抗结核治疗,为此应引起临床对本病诊治的重视。

Sarcoidosis

Type 2 diabetes mellitus (T2DM) is an expanding global health problem, closely linked to the epidemic of obesity. Individuals with T2DM are at high risk for both microvascular complications (including retinopathy, nephropathy and neuropathy) and macrovascular complications (such as cardiovascular comorbidities), owing to hyperglycaemia and individual components of the insulin resistance (metabolic) syndrome. Environmental factors (for example, obesity, an unhealthy diet and physical inactivity) and genetic factors contribute to the multiple pathophysiological disturbances that are responsible for impaired glucose homeostasis in T2DM. Insulin resistance and impaired insulin secretion remain the core defects in T2DM, but at least six other pathophysiological abnormalities contribute to the dysregulation of glucose metabolism. The multiple pathogenetic disturbances present in T2DM dictate that multiple antidiabetic agents, used in combination, will be required to maintain normoglycaemia. The treatment must not only be effective and safe but also improve the quality of life. Several novel medications are in development, but the greatest need is for agents that enhance insulin sensitivity, halt the progressive pancreatic β-cell failure that is characteristic of T2DM and prevent or reverse the microvascular complications. For an illustrated summary of this Primer, visit: http://go.nature.com/V2eGfN.

Type 2 diabetes mellitus.

The impact of psoriasis on the outcomes of Coronavirus disease 2019 (COVID‐19) is yet to be precisely delineated.

Nineteen months into the pandemic, what have we learned about COVID‐19‐related outcomes in patients with psoriasis?

The epidemiological relationship of vitiligo with systemic sclerosis (SSc) remains to be precisely evaluated.

Vitiligo and systemic sclerosis: Are they associated?– Lessons from a population‐based study

INTRODUCTION: Monitoring methods for the early diagnosis of one-lung intubation (OLI) are nonspecific and controversial. In this study, we evaluated a new acoustic monitoring system for the detection of OLI. METHODS: Lung sounds were collected from 24 adult surgical patients scheduled for routine surgical procedures. Four piezoelectric microphones attached to the patients' backs were used to sample lung sounds during induction of anesthesia and endotracheal tube positioning. To achieve OLI, the endotracheal tube was inserted and advanced down the airway so that diminished or no breath sounds were heard on the left side of the chest. The tube was then withdrawn stepwise until equal breath sounds were heard. Fiberoptic bronchoscopy confirmed the tube's final position. Acoustic analyses were preformed by a new algorithm which assumes a Multiple Input Multiple Output system, in which a multidimensional Auto-Regressive model relates the input (lungs) and the output (recorded sounds) and a classifier, based on a Generalized Likelihood Ratio Test, indicates the number of ventilated lungs without reconstructing the original lung sounds from the recorded samples. RESULTS: This algorithm achieved an OLI detection probability of 95.2% with a false alarm probability of 4.8%. CONCLUSION: Higher detection values can be achieved at the price of a higher incidence of false alarms.

Acoustic Monitoring of Lung Sounds for the Detection of One Lung Intubation.

Chronic penoscrotal oedema: a presenting sign for Crohn's disease.

ABSTRACT Purpose The main objective of the study is to investigate the prevalence of anxiety in patients with neovascular age-related macular degeneration (nAMD). Methods A retrospective cross-sectional study of 3 304 nAMD patients and 16 515 age- and gender-matched controls. The proportions of patients with anxiety were compared between the groups using univariate analyses and a multivariate logistic regression model. Proportion of anxiety in patients with nAMD was compared with the proportion of anxiety in controls, matched for age and gender. Data was obtained from the largest health maintenance organization in Israel (Clalit Health Services) with 4 200 000 members. Results The mean age of patients was 79.7 years; 54.8% were females; Anxiety was more common in patients with nAMD (13.2%) compared to the control group (10.2%) (OR 1.3; 95%CI 1.2–1.5). Multivariate logistic regression analysis revealed a significant association between anxiety and nAMD (OR 1.3; 95% CI: 1.2–1.5), adjusted for age, gender, and socio-economic status. Conclusion Our study demonstrated that anxiety is more common in patients with nAMD compared to a control group. Physicians treating patients with nAMD should be aware of this association, in order to provide appropriate care for the anxiety associated with nAMD.

Arnon D. Cohen

Papers

Nineteen months into the pandemic, what have we learned about COVID‐19‐related outcomes in patients with psoriasis?

Vitiligo and systemic sclerosis: Are they associated?– Lessons from a population‐based study

Acoustic Monitoring of Lung Sounds for the Detection of One Lung Intubation.

Chronic penoscrotal oedema: a presenting sign for Crohn's disease.

Anxiety in Patients with Neovascular Age-related Macular Degeneration