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Pulmonary veno-occlusive disease (PVOD) is a rare cause of pulmonary hypertension. Heritable and sporadic forms have been distinguished. Hypoxemia, profound reduction in the diffusion of carbon monoxide and haemodynamic confirmation of pre-capillary pulmonary hypertension are the major diagnostic criteria. Thoracic CT scanning and a response to pharmaceutical therapy provide additional information to confirm the diagnosis. A 52-year-old patient, three of whose siblings had pulmonary hypertension, was admitted with dyspnoea, malaise and palpitations. Right heart catheterisation confirmed pre-capillary pulmonary hypertension. A search for an EIF2AK4 mutation was carried out, and this showed a composite biallelic heterozygous mutation compatible with the diagnosis of familial PVOD, identical to that showed in one of his brothers. Given the signs of severity of the disease and the diagnosis of PVOD, whose response to pharmaceutical therapy is often poor, the patient was placed on a waiting list for lung transplantation. Despite a similar diagnosis in 3 brothers and follow-up proposed 11 years before the diagnosis, pulmonary hypertension appeared within a few weeks and led immediately to a severe clinical situation. Annual clinical and echocardiographic monitoring had been strongly advised to the patient, but had not allowed diagnosis at a mild or moderate stage of the disease. This clinical case shows that the identification of factors predicting the development of heritable PVOD at a pre-symptomatic stage is an important issue for clinical research.

With first cases noted towards the end of 2019 in China, COVID-19 infection was rapidly become a devastating pandemic. Even if most patients present with a mild to moderate form of the disease, the estimated prevalence of COVID-19-related severe acute respiratory failure (ARF) is 15-20% and 2-12% needed intubation and mechanical ventilation. In addition to mechanical ventilation some other techniques of respiratory support could be used in some forms of COVID-19 related ARF. This position paper of the Respiratory Support and Chronic Care Group of the French Society of Respiratory Diseases is intended to help respiratory clinicians involved in care of COVID-19 pandemic in the rational use of non-invasive techniques such as oxygen therapy, CPAP, non-invasive ventilation and high flow oxygen therapy in managing patients outside intensive care unit (ICU). The aims are: (1) to focus both on the place of each technique and in describing practical tips (types of devices and circuit assemblies) aimed to limit the risk of caregivers when using those techniques at high risk spreading of viral particles; (2) to propose a step-by-step strategy to manage ARF outside ICU.

Pulmonary veno-occlusive disease (PVOD) is a rare cause of pulmonary hypertension. Heritable and sporadic forms have been distinguished. Hypoxemia, profound reduction in the diffusion of carbon monoxide and haemodynamic confirmation of pre-capillary pulmonary hypertension are the major diagnostic criteria. Thoracic CT scanning and a response to pharmaceutical therapy provide additional information to confirm the diagnosis. A 52-year-old patient, three of whose siblings had pulmonary hypertension, was admitted with dyspnoea, malaise and palpitations. Right heart catheterisation confirmed pre-capillary pulmonary hypertension. A search for an EIF2AK4 mutation was carried out, and this showed a composite biallelic heterozygous mutation compatible with the diagnosis of familial PVOD, identical to that showed in one of his brothers. Given the signs of severity of the disease and the diagnosis of PVOD, whose response to pharmaceutical therapy is often poor, the patient was placed on a waiting list for lung transplantation. Despite a similar diagnosis in 3 brothers and follow-up proposed 11 years before the diagnosis, pulmonary hypertension appeared within a few weeks and led immediately to a severe clinical situation. Annual clinical and echocardiographic monitoring had been strongly advised to the patient, but had not allowed diagnosis at a mild or moderate stage of the disease. This clinical case shows that the identification of factors predicting the development of heritable PVOD at a pre-symptomatic stage is an important issue for clinical research.

By means of Raman scattering, photoluminescence, and x-ray diffraction experiments, we have studied a series of ultrathin $\mathrm{In}\mathrm{As}∕\mathrm{In}\mathrm{P}$ single quantum wells grown with nominal well thickness varying between one and four monolayers. The observed Raman peaks are attributed to the first InAs-confined longitudinal optical phonon. When the quantum well is thinner than three monolayers, the measured frequencies of the confined modes depart from the predictions of the standard confined-phonon model but are in good agreement with the results of ab initio calculations based on density-functional theory. This indicates that there is a significant penetration of the InAs layer vibrations in the InP barriers and that thickness fluctuations occur at a scale short enough to further shift the phonon frequencies. When the wells contain more than three monolayers, a doublet Raman structure is observed which parallels the evolution of the photoluminescence spectra from single- to multiple-peak emission. We associate this simultaneous change in Raman and photoluminescence spectra with the two- to three-dimensional growth-mode transition.

Low energy ion implantation of InP heterostructures has proved to be an efficient way to induce controlled quantum well intermixing. A significant blue‐shift, dependent on local ion dose, appears after a 600°C anneal, which is not observed in the unimplanted regions. Thus, this technique makes possible the fabrication of integrated photonic devices working at several wavelengths. However, it has been observed that the shift is also influenced by the implantation temperature: 200°C implants induce much more intermixing than room temperature implants. In this paper, we will establish a relation between the implant temperature, the induced blue‐shift and the amount of defects in the implanted region, as measured by channeling‐RBS. A much lower defect concentration is observed for higher temperature implants, which implies that a significant number of defects diffuse in‐depth during the implantation in order to provide efficient intermixing.

Scanning Electron Microscopy (SEM) was used to study changes during the preparation of plasteins from egg albumin and corn zein protein isolates. This included an examination of protein particles that had been spray-dried, freeze-dried, hydrolyzed, and synthesized into plastein reaction products. Water holding capacity, oil binding capacity, and gel strength properties before and after modification are discussed. The study demonstrated that the quantity and quality of plastein products are dependent upon both the substrate and the enzyme used. A possible relationship is proposed between ultrastructural characteristics and actual functional performance of unmodified and modified proteins.

The adsorption of several iron compounds by unmodified and modified tapioca, corn and waxy maize starch was studied using transmission electron microscopy and atomic absorption spectrophotometry. Starch was incubated in an iron-containing solution. After centrifugation the amount of iron remaining in solution was compared to the original concentration to determine the quantity bound by the starch. Only iron in the form of colloidal ferric chloride showed significant binding. Long, cigar shaped structures, probably β-ferric oxyhydroxide crystals, were seen embedded in the surface of the granule. It is postulated that the oxygen and hydroxide groups surrounding the iron are responsible for binding to the carbohydrate. The study of the interaction of starch and metal compounds may lead to greater insight into methods of fortifying food products.

The ultrastructural changes occurring during germination of spores of Penicillium roqueforti were examined using transmission electron microscopy on thin sections and freeze-etch replicas. The cell wall of the resting spore was composed of four distinct layers. The outermost layer ruptured and peeled off as the spores became swollen during the initial stages of germination. The germ tube, which emerged from the spore, had a thin cell wall which lacked the outer layers observed in the resting spore. As the germ tube transformed to mycelia it acquired extra outer layers so that the cell wall possessed three layers of material. Germinating spores were multinucleated. Membranous sacs and vesicles and endoplasmic reticulum were observed both in germinated spores and in mycelia. Freeze fracture techniques revealed that the surface of spores was covered with a layer of interwoven fibrils. This technique also confirmed the presence of distinct layers in the cell wall. The capacity of snail digestive enzymes to hydrolyze cell wall material was demonstrated.

The 2 chloroplast ribosome deficient mutants of Chlamydomonas reinhardi , ac-20 and cr-I form low levels of 66-s and 70-s chloroplast ribosome monomers compared to wild type, but differ in that cr-I also accumulates substantial amounts of the large (54-S) chloroplast subunit. Unlike wild type, ac-20 , cr-I and the double mutant ac-20 cr-I make little or none of the CO 2 - fixing enzyme ribulose diphosphate carboxylase (RuDPCase) when grown in the light with acetate and CO 2 as carbon sources ( mixotrophic growth ) whereas all 3 mutant genotypes form at least some enzyme when grown photosynthetically with CO 2 as the sole carbon source ( phototrophic growth ). All 3 mutant genotypes also show a characteristic defect in the organization of their chloroplast lamellar system when grown mixotrophically, but their chloroplast membrane organization approaches that of wild type when grown phototrophically. No change in the level of chloroplast ribosomes accompanies these changes in chloroplast organization and RuDPCase formation. We propose that the pleiotropic effects on chloroplast structure and function in mixotrophically grown cells of the mutants result because their chloroplast ribosomes synthesize certain specific chloroplast components with low efficiency, whereas they perform this function with greater efficiency when the cells are grown phototrophically.

Previous reports described the induction of avian renal neoplasms by leukosis virus strains BAI A [avian myeloblastosis virus (AMV)] and MC29, and illustrated morphological characteristics of the tumors. Continued studies in this work confirm evidence of the origin of the tumors from embryonal cells residual in the posthatched chick. The work further emphasizes differences in histopathology of the neoplasms caused by the two viruses and reveals differences in the histopathogenesis of the respective growths. Embryonal rests may consist of two types of cells, those of epithelial characteristics and a second element of differentiation between nephroblastema (mesenchyme) and epithelium and designated here as nephromesoblastoma. Infection by AMV induces tumors of epithelial characteristics and, in addition, derivatives of nephromesoblastoma consisting of cartilage, bone, areas of keratinization, and sarcoma. Keratinized structures in the nephroblastoma originate from nephromesoblastoma. In contrast, MC29 virus induces only epithelial growths representing principally aberrant and malformed glomerular and tubular structures with occasional cartilage derived from epithelial cells. MC29 tumors are completely lacking in nephromesoblastoma tissue and contain no bone, sarcoma, or keratinized formations. In MC29 tumors, occasional cartilage was derived from epithelium. Tumors caused by AMV exhibit the complex structure of nephroblastoma with all of the features of the growth in humans (Wilms' tumor). The neoplasms induced by both AMV and MC29 exhibit marked aberration, distortion, and malformation in the differentiation of the cells growing out from the embryonal rests representing rare manifestations of cell genetic influence inherent in the primordial growth of nephroblastema. The results thus illustrate fundamental differences in cellular composition and capacity to respond to etiologically different leukosis viruses.

An ion microscope has been used to demonstrate that the calcium ion is present in the amyloplasts of root-cap cells of corn, pea, and lettuce. The localization of calcium in the gravity-sensing organelle suggests a possible role of calcium in the gravity-sensing mechanism of plant roots.

Three clones of morphologically altered cells (L − MC29) of singular properties were isolated from MC29 (subgroup A) leukosis virus-infected chick embryo cells. Supernatant fluids from cultures of the cloned cells produced no transforming or interfering activity on chick embryo cells susceptible to known avian leukosis-sarcoma viruses. No virus associated with the cells was demonstrable by fluorescent-antibody staining or by electron microscopy. All L − MC29 clone cells were activated, however, by four strains of Rous-associated viruses (RAV) representative of A, B, C, and D subgroup avian leukosis viruses and by two strains of MC29 virus. Virus L − MC29 cells activated by superinfection with RAV-1 and RAV-2 was characterized by helper-dependent and helper-independent properties. These findings suggest that the strain MC29 leukosis virus, or a component thereof, possesses properties of defectiveness similar to those of the Bryan high-titer Rous sarcoma virus.