Amyloid stained by Congo red is traditionally said to show apple-green birefringence in polarized light, although in practice various colors may be seen between accurately crossed polarizing filters, called polarizer and analyzer. Other colors are seen as the polarizer and analyzer are uncrossed and sometimes when the slide is rotated. Previously, there has been no satisfactory explanation of these properties. Birefringence means that a material has two refractive indices, depending on its orientation in polarized light. Birefringence can change linearly polarized light to elliptically polarized, which allows light to pass a crossed analyzer. The birefringence of orientated Congo red varied with wavelength and was maximal near its absorption peak, changing from negative (slow axis of transmission perpendicular to smears or amyloid fibrils) on the shortwave side of the peak to positive (slow axis parallel) on the longwave side. This was explained by a property of any lightabsorbing substance called anomalous dispersion of the refractive index around an absorption peak. Negative birefringence gave transmission of blue, positive gave yellow, and the mixture was perceived as green. This explains how green occurs in ideal conditions. Additional or strain birefringence in the optical system, such as in glass slides, partly or completely eliminated blue or yellow, giving yellow/green or yellow, and blue/green or blue, which are commonly seen in practice and in illustrations. With uncrossing of polarizer or analyzer, birefringent effects declined and dichroic effects appeared, giving progressive changes from green to red as the plane of polarization approached the absorbing axis and from green to colorless in the opposite way. This asymmetry of effects is useful to pathologists as a confirmation of amyloid. Rather than showing 'apple-green birefringence in polarized light' as often reported, Congo red-stained amyloid, when examined between crossed polarizer and analyzer, should more accurately be said to show anomalous colors.

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Organization of TrialThe nephrotic syndrome was considered to be present when all the following criteria were met: (a) oedema-still present or recently observed; (b) proteinuria-5 g. or more per day, measured by biuret or turbidimetric method, not Esbach's method; and (c) hypoproteinaemia-serum albumin less than 3 g./100 ml. Only those patients were admitted to the trial who: (a) were aged 15 or over; (b) had suffered from the nephrotic syndrome, as defined above, for not more than one year; (c) had not been previously treated for this condition with steroids or with corticotrophin; (d) were still excreting in the urine, at the end of a preliminary period of four weeks, at least 1 g. of protein per day; (e) showed neither pathological nor strong clinical evidence of a cause for the nephrotic syndrome other than glomerulonephritis; (f) had nc past history of episodes of the nephrotic syndrome except during the year immediately preceding admission to the trial; and (g) had not received, steroids or corticotrophin for any condition during the, past year.A history of proteinuria extending over more than a year, without other features of the nephrotic syndrome, did not entail exclusion from the trial, nor did uraemia, hypertension, or urinary infection.In order to obtain sufficient data within a reasonable period a multi-centre trial was necessary. A total of 125 patients who satisfied all the clinical and histologicaL criteria for entry were admitted to the trial in 19 centres over a period of three and a half years. An almost equal number of patients suffering from the nephrotic syndrome had to be rejected for a variety of clinical reasons. Clinical information on patients admitted to the trial was recorded on a standard form, and they were observed for a month before being allocated to "steroid" or "non-steroid" groups. Histological ClassificationThe nephrotic syndrome has a great number of possible causes, but in any large series about three-quarters of the patients are suffering from one form of glomerulonephritis or another. Even within the category of glomerulonephritis, however, there is great histological diversity, and this is associated with differences in aetiology and probably in

Global Collaboration on Traumatic Stress (GC-TS) (2020) Screening for consequences of trauma-an update on the global collaboration on traumatic stress,

SummaryMax Schultze published the first accurate and convincing description of platelets as part of a study devoted mainly to the white blood cells in 1865. He recognised them as a normal constituent of the blood and 'enthusiastically recommended' them as an object for further study by 'those concerned with the in-depth study of the blood of humans'. In 1882, Bizzozero demonstrated the value of this recommendation in his much more comprehensive study. He observed them microscopically in the circulating blood of living animals and in the blood removed from the blood vessels. In well-planned experiments, he showed that they were the first component of the blood to adhere to damaged blood vessel walls in vivo and, in vitro, that they were the first components of the blood to adhere to threads that subsequently became covered with fibrin.

PLATES CLIV-CLVI CHRONIC hypoxia, irrespective of its cause, is associated with pulmonary arterial hypertension. Thus pulmonary hypertension occurs in normal people living at high altitudes and in sufferers from so-called " chronic mountain sickness" (Monge's disease) where the hypoxia is due to low barometric pressure (Peiialoza et al., 1963). It also occurs in patients with diseases such as emphysema (Whitaker, 1954) where the hypoxia is due to abnormal diffusion of air into the alveolar spaces and the " Pickwickian syndrome " (Auchincloss, Cook and Renzetti, 1955) in which extreme obesity leads to inadequate respiration. Over the past decade it has been shown that elevation of the pulmonary arterial pressure is not always associated with the same histological changes in the small pulmonary arteries, but rather that the type of hypertensive pulmonary vascular disease present depends on the nature of the pulmonary hypertension (Harris and Heath, 1962). Thus, for example, the pulmonary vascular changes in the hyperkinetic pulmonary arterial hypertension of pre-and post-tricuspid shunts differ considerably from those associated with passive pulmonary hypertension complicating left atrial hypertension, We have now shown that there is a type of hypertensive pulmonary vascular disease that is characteristically associated with chronic hypoxia. At the same time we have studied the relations of the terminal air passages to the pulmonary vascular tree. METHOD AND MATERIALSWe studied 11 patients with chronic hypoxia and 2 patients free of cardiopulmonary disease (controls 1 and 2). The diagnosis, age, sex, body weight and height were recorded and where available the systemic and pulmonary arterial blood pressure, Po,, Pm, and haemoglobm level (table I).The diagnosis of alveolar and bronchiolar emphysema in patients 3-6 was made after the lungs had been fixed in formalin-steam by the method of Weibel and Vidone (1961). The lungs from patients 10 and 11 and from the two controls were fixed by the same technique. The lungs from patients 7-9 were fixed by perfusion of 4 per cent. formaldehyde into the bronchial tree. The lungs were sliced and blocks were cut from each slice and vacuumembedded in paraffin wax. Sections (6 p thick) were stained with the Lawson modification of the Weigert-Sheridan method for elastin with a Van Gieson counterstain for fibrous tissue and muscle. The sections of lung were used to study qualitative changes in the small pulmonary

We describe a distinctive and previously undescribed abnormality of the kidney. It consists of a combination of changes in the glomerulus and in the proximal convoluted tubule. The glomerular abnormality consists of a well-localized collection of intracapillary foam cells and marked vacuolation of the adjacent glomerular epithelial cells. The abnormality is always situated in the same position in the glomerular tuft namely adjacent to the origin of the proximal convoluted tubule, with adhesion to Bowman's capsule. The rest of the tuft appears normal by light microscopy but shows foot-process fusion by electron microscopy. The abnormality of the proximal convoluted tubular cells invariably affects the first part of the tubule adjacent to the glomerulus but in some cases involves the tubules more extensively in the cortex. Study of a series of 100 2-micron serial sections from one case indicated that probably every glomerulus had a lesion at the origin of the tubule. A study of 185 renal biopsies nearly all with segmental lesions revealed biopsies from 20 patients with this distinctive abnormality. There were 14 males, age 20-57, median 44 years, and six females age 19-65, median 22 years, all presenting with proteinuria, nearly all with the nephrotic syndrome. All except four were treated with steroids and in all those treated the proteinuria improved. Only one patient not treated with steroids had progressive renal impairment. Four patients died, none from renal failure. This lesion, the glomerular tip lesion, as we have called it, seems to be a well-defined and specific pathological entity. It has some similarities to minimal change nephropathy but there are clear and important differences. Previously it may have been included in series of cases of 'focal glomerulosclerosis' but that term is imprecise and is generally taken to have an unfavourable clinical course. For these reasons it is inappropriate to use 'focal glomerulosclerosis' as a name for the glomerular tip lesion.

Trauma is a global issue. The great majority of the global burden of disease arising from mental health conditions occurs in low- and middle-income countries (LMICs), among populations in political, economic, and/or cultural transition and those struck by forced migration. These mental health problems frequently arise as a result of traumatic events that adversely affect adults, children, and families, including war, mass violence, natural disasters, and accidents. In response to this, the International Society for Traumatic Stress Studies (ISTSS) launched the Global Initiative to have a stronger global impact on trauma-related issues. As part of this initiative, the Global Collaboration was established by representatives of eight professional organizations active in the field of traumatic stress. The group decided to focus on childhood abuse and neglect as its first collaboration. They collected guidelines worldwide, providing the basis for a synthesized core guide for prevention and treatment that can be customized for specific cultural contexts. The resulting ‘Internet information on Childhood Abuse and Neglect’ (iCAN) is a comprehensive guide for adults who have been affected by childhood abuse and neglect, as well as for the survivors’ significant others. It is currently provided in eight languages, and is freely available at the homepage of ISTSS and other websites. A second achievement of the Global Collaboration is the validation of the Computerized Childhood Attachment and Relational Trauma Screen (CARTS), a self-report measure designed to measure occurrences of childhood maltreatment, and its translation into multiple languages, including Croatian, Dutch, French, Georgian, German, Italian, Japanese, Norwegian, Russian, and Spanish. A study is currently planned to collect normative responses to the questionnaire, and to conduct cross-cultural comparisons. The Global Collaboration’s success may be seen as an encouraging step towards a truly global structure in the field of traumatic stress.